From gagsl-py2 at yahoo.com.ar  Wed Jul  1 00:15:06 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 01 Jul 2009 01:15:06 -0300
Subject: invoking a method from two superclasses
References: <mailman.8861.1246401585.8014.python-list@python.org>
	<p06240807c6705db3787d@[10.0.1.221]>
Message-ID: <op.uwdffgffx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 30 Jun 2009 21:34:02 -0300, Mitchell L Model  
<MLMLists at comcast.net> escribi?:

> Allow me to add to my previous question that certainly the superclass
> methods can be called explicitly without resorting to super(), e.g.:
>
>     class C(A, B):
>         def __init__(self):
>             A.__init__(self)
>             B.__init__(self)
>
> My question is really whether there is any way of getting around the
> explicit class names by using super() and if not, shouldn't the  
> documentation
> of super point out that if more than one class on the mro defines a  
> method
> only the first will get called?

super returns [a proxy to] the *next* class in the MRO chain; it may or  
may not be a superclass of C (it may be a sibling class instead). If you  
know that only A B and C are involved and no other subclass ever exists,  
yes, you can explicitely invoke A.__init__ and B.__init__. If not (and  
this covers the vast majority of cases) using super in all places is the  
only way to get correct results (for details, see the "Harmful" article by  
James Knight [1] that someone has already referenced)

Note that doing it right with __init__ is tricky: usually, cooperative  
methods share the same signature so the super() call just passes the same  
arguments to the next class in the chain. But isn't uncommon for __init__  
to have different signatures for different subclasses; the article [1]  
contains a recipe for this case.

> What's strange is that it specifically mentions diamond patterns, which  
> is an important caseto get right, but it doesn't show how.

The "typical superclass call" in the 2.6 docs is, uhm, typical :) - in  
principle you use it everywhere you have cooperative classes. For the sake  
of completeness I'll copy it here:

class C(A, B):
     def method(self, arg):
         super(C, self).method(arg)

(you may simply use super().method(arg) in Python 3). Every implementation  
of method() in the class hierarchy should contain a super call like above  
(well, it gets somewhat more complex due to error handling, but you get  
the idea...)

In addition to the "Harmful" document, consider reading the three-article  
series by M. Simionato [2] which explains the problem from a different  
point of view.

[1] Python's Super Considered Harmful
http://fuhm.net/super-harmful/

[2] http://www.artima.com/weblogs/viewpost.jsp?thread=236275

-- 
Gabriel Genellina



From nmartelaro at gmail.com  Wed Jul  1 00:51:37 2009
From: nmartelaro at gmail.com (Nik Martelaro)
Date: Wed, 1 Jul 2009 00:51:37 -0400
Subject: Streaming Webcam over network
Message-ID: <885d14c40906302151u57d7005n5532093d68d2c786@mail.gmail.com>

Hi eveyone,
I am working on a project that requires streaming video from a webcam over
LAN and displaying the live video on the remote computer. Basically, I am
creating a specialized video chat client. I can get really nice video
locally using VideoCapture and Pygame, however have only been able to send
pixel data and recreate a single image at the other end. Does anyone know of
a good video streaming module or any other way of doing this in Python?

Thanks for any help!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/c8a878ff/attachment.html>

From rylesny at gmail.com  Wed Jul  1 00:52:52 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 30 Jun 2009 21:52:52 -0700 (PDT)
Subject: Making code run in both source tree and installation path
References: <mailman.2310.1246292443.8015.python-list@python.org>
Message-ID: <ca05a251-3fd3-4026-9f25-cf310844928c@j14g2000vbp.googlegroups.com>

On Jun 29, 12:20?pm, Javier Collado <javier.coll... at gmail.com> wrote:
> Hello,
>
> I would like to be able to run the main script in a python project
> from both the source tree and the path in which it's installed on
> Ubuntu. The script, among other things, imports a package which in
> turns makes use of some data files that contains some metadata that is
> needed in xml format.
>
> The source tree has an structure such as this one:
> setup.py
> debian/ (packaging files)
> src/ (source code)
> src/lib (package files)
> src/data (data files)
> src/bin (main script)
>
> However, when the project is installed using setup.py install, the
> directory structure is approximately this way:
> /usr/local/bin (main script)
> /usr/local/share/<project_name> (data files)
> /usr/local/lib/python2.x/dist-packages/<project_name> (library files)
>
> And when installing the code through a package, the structure is the
> same one, but removing "local".
>
> Hence, the data files aren't always in the same relative directories
> depending on we're executing code from the source tree or from the
> installation. To make it possible to run the code from both places,
> I've seen different approaches:
> - distutils trick in setup.py to modify the installed script (i.e.
> changing a global variable value) so that it has a reference to the
> data files location.
> - Heuristic in the package code to detect when it's being executed
> from the source tree and when it has been the installed
> - Just using an environment variable that the user must set according
> to his needs
>
> I guess that there are other options, for example, maybe using
> buildout. What would you say it's the best/more elegant option to
> solve this problem?
>
> Best regards,
> ? ?Javier

It's kludgey, but one option may be to try and use __file__ to figure
out where the script is installed. Something like os.path.dirname
(os.path.abspath(__file__)) could tell you if it's in src/ or in the
bin/ directory, and then data files could be found in the appropriate
place.

I like the distutils/variable option better. Your script is more
likely to still behave correctly when copied to another directory.
Plus its code definitely remains cleaner.


From gagsl-py2 at yahoo.com.ar  Wed Jul  1 00:54:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 01 Jul 2009 01:54:45 -0300
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
Message-ID: <op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 30 Jun 2009 22:52:18 -0300, Mag Gam <magawake at gmail.com> escribi?:

> I am very new to python and I am in the process of loading a very
> large compressed csv file into another format.  I was wondering if I
> can do this in a multi thread approach.

Does the format conversion involve a significant processing time? If not,  
the total time is dominated by the I/O time (reading and writing the file)  
so it's doubtful you gain anything from multiple threads.

> Here is the pseudo code I was thinking about:
>
> Let T  = Total number of lines in a file, Example 1000000 (1 million  
> files)
> Let B = Total number of lines in a buffer, for example 10000 lines
>
>
> Create a thread to read until buffer
> Create another thread to read buffer+buffer  ( So we have 2 threads
> now. But since the file is zipped I have to wait until the first
> thread is completed. Unless someone knows of a clever technique.
> Write the content of thread 1 into a numpy array
> Write the content of thread 2 into a numpy array

Can you process each line independently? Is the record order important? If  
not (or at least, some local dis-ordering is acceptable) you may use a few  
worker threads (doing the conversion), feed them thru a Queue object, put  
the converted lines into another Queue, and let another thread write the  
results onto the destination file.

import Queue, threading, csv

def convert(in_queue, out_queue):
   while True:
     row = in_queue.get()
     if row is None: break
     # ... convert row
     out_queue.put(converted_line)

def write_output(out_queue):
   while True:
     line = out_queue.get()
     if line is None: break
     # ... write line to output file

in_queue = Queue.Queue()
out_queue = Queue.Queue()
tlist = []
for i in range(4):
   t = threading.Thread(target=convert, args=(in_queue, out_queue))
   t.start()
   tlist.append(t)
output_thread = threading.Thread(target=write_output, args=(out_queue,))
output_thread.start()

with open("...") as csvfile:
   reader = csv.reader(csvfile, ...)
   for row in reader:
     in_queue.put(row)

for t in tlist: in_queue.put(None) # indicate end-of-work
for t in tlist: t.join() # wait until finished
out_queue.put(None)
output_thread.join() # wait until finished

-- 
Gabriel Genellina



From MLMLists at Comcast.net  Wed Jul  1 00:57:13 2009
From: MLMLists at Comcast.net (Mitchell L Model)
Date: Wed, 1 Jul 2009 00:57:13 -0400
Subject: invoking a method from two superclasses
Message-ID: <p0624080cc670986339c1@[10.0.1.221]>

[Continuing the discussion about super() and __init__]

The documentation of super points out that good design of diamond patterns require the methods to have the same signature throughout the diamond. That's fine for non-mixin classes where the diamond captures different ways of handling the same data. The classical example is 

	BufferedStram
	     / \
	  /       \
	/           \
     BufInputStrm    BufOutputStrm		both have buffers, but use them differentlyu
	\            /
 	  \        /
	    \    /
	RandomAccessStream		or something like that

The idea of the diamond is to have just one buffer, rather than the two buffers that would result in C++ without making the base classes virtual.  All four classes could define __init__ with the argument
filename, or whatever, and everything works fine.

The problems start with the use of mixins. In essence, mixins intentionally do NOT want to be part of diamond patterns. They are orthogonal to the "true" or "main" class hierarchy and just poke their heads in hear and there in that hierarchy. Moreover, a class could inherit from multiple mixins. Typical simple orthogonal mixins would be NamedObject, TrackedObject, LoggedObject, ColoredWidget, and other such 
names compounded from an adjective, participle, or gerund and a completely meaningless name such as Object or Thing and which classes typically manage one action or piece of state to factor it out from the many other classes that need it where the pattern of which classes need them does not follow the regular class hierarchy.  Suppose I have a class User that includes NamedObject, TrackedObject, and LoggedObject as base classes. (By Tracked I mean instances are automatically registered in a list or dictionary for use by class methods that search, count, or do other operations on them.)

The problem is that each mixin's __init__ is likely to have a different signature. User.__init__
would have arguments (self, name, log), but it would need to call each mixin class's __init__ with different arguments. Mixins are different than what the document refers to as cooperative multiple inheritance -- does that make them uncooperative multiple inheritance classes :-)? I think I'd be back to having to call each mixin class's __init__ explicitly:

	class User(NamedObject, TrackedObject, LoggedObject)
		def __init__(self, name, log):
			NamedObject.__init__(self, name)
			TrackedObject.__init__(self)
			LoggedObject.__init__(self, log)

This is not terrible. It seems somehow appropriate that because mixin use is "orthogonal" to the "real" inheritance hierarchy, they shouldn't have the right to use super() and the full mro (after all, who knows where the mro will take these calls anyway). And in many cases, two mixins will join into another (a NamedTrackedObject) for convenience, and then classes inheriting from that have one less init to worry about.

I suspect this problem is largely with __init__. All the other __special__ fns have defined argument lists and so can be used with diamond patterns, mixins, etc.

Does this all sound accurate?  (Again, not looking for design advice, just trying to ferret out the subtleties and implications of multiple inheritance and super().)


From rylesny at gmail.com  Wed Jul  1 01:00:10 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 30 Jun 2009 22:00:10 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org> 
	<Xf-dnUHy7ad9rtTXnZ2dnUVZ_rSdnZ2d@pdx.net>
Message-ID: <b1d86eff-c1a6-45b7-9784-9137f5e1c2a2@f33g2000vbm.googlegroups.com>

On Jun 29, 5:43?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>?and I personally wouldn't have it any other way.  Simulating a shell
> with hooks on its I/O should be so complicated that a "script kiddie"
> has trouble writing a Trojan.

+1 QOTW


From ldo at geek-central.gen.new_zealand  Wed Jul  1 01:07:47 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 17:07:47 +1200
Subject: Multi thread reading a file
References: <mailman.2420.1246413152.8015.python-list@python.org>
Message-ID: <h2eqv3$gpt$4@lust.ihug.co.nz>

In message <mailman.2420.1246413152.8015.python-list at python.org>, Mag Gam 
wrote:

> I am very new to python and I am in the process of loading a very
> large compressed csv file into another format.  I was wondering if I
> can do this in a multi thread approach.

Why bother?



From ldo at geek-central.gen.new_zealand  Wed Jul  1 01:19:30 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 17:19:30 +1200
Subject: Idioms and Anti-Idioms Question
References: <mailman.1932.1245644100.8015.python-list@python.org>
	<H0F%l.20231$y61.5030@news-server.bigpond.net.au>
	<slrnh402pc.deb.peter@box8.pjb.com.au>
	<mailman.2018.1245772229.8015.python-list@python.org>
Message-ID: <h2erl2$h7l$1@lust.ihug.co.nz>

In message <mailman.2018.1245772229.8015.python-list at python.org>, J. Cliff 
Dyer wrote:

> If the lines got separated, a leading + could disappear into its line
> without any errors showing up.  A trailing + would raise a syntax error.

Unless, of course, it was moved onto the previous line as part of whatever 
caused the separation of the lines. How would you guard against that?



From stefan_ml at behnel.de  Wed Jul  1 01:30:13 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Wed, 01 Jul 2009 07:30:13 +0200
Subject: Multi thread reading a file
In-Reply-To: <mailman.2426.1246424006.8015.python-list@python.org>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
Message-ID: <4a4af466$0$31328$9b4e6d93@newsspool4.arcor-online.net>

Gabriel Genellina wrote:
> En Tue, 30 Jun 2009 22:52:18 -0300, Mag Gam <magawake at gmail.com> escribi?:
> 
>> I am very new to python and I am in the process of loading a very
>> large compressed csv file into another format.  I was wondering if I
>> can do this in a multi thread approach.
> 
> Does the format conversion involve a significant processing time? If
> not, the total time is dominated by the I/O time (reading and writing
> the file) so it's doubtful you gain anything from multiple threads.

Well, the OP didn't say anything about multiple processors, so multiple
threads may not help wrt. processing time. However, if the file is large
and the OS can schedule the I/O in a way that a seek disaster is avoided
(although that's hard to assure with today's hard disk storage density, but
SSDs may benefit), multiple threads reading multiple partial streams may
still reduce the overall runtime due to increased I/O throughput.

That said, the OP was mentioning that the data was compressed, so I doubt
that the I/O bandwidth is a problem here. As another poster put it: why
bother? Run a few benchmarks first to see where (and if!) things really get
slow, and then check what to do about the real problem.

Stefan


From pavlovevidence at gmail.com  Wed Jul  1 01:37:19 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 30 Jun 2009 22:37:19 -0700 (PDT)
Subject: invoking a method from two superclasses
References: <mailman.8861.1246401585.8014.python-list@python.org> 
	<p06240807c6705db3787d@[10.0.1.221]>
	<mailman.2424.1246421638.8015.python-list@python.org>
Message-ID: <65fa395e-0ac1-4b64-9792-74323ecbecc8@a36g2000yqc.googlegroups.com>

On Jun 30, 9:15?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Tue, 30 Jun 2009 21:34:02 -0300, Mitchell L Model ?
> <MLMLi... at comcast.net> escribi :
>
> > Allow me to add to my previous question that certainly the superclass
> > methods can be called explicitly without resorting to super(), e.g.:
>
> > ? ? class C(A, B):
> > ? ? ? ? def __init__(self):
> > ? ? ? ? ? ? A.__init__(self)
> > ? ? ? ? ? ? B.__init__(self)
>
> > My question is really whether there is any way of getting around the
> > explicit class names by using super() and if not, shouldn't the ?
> > documentation
> > of super point out that if more than one class on the mro defines a ?
> > method
> > only the first will get called?
>
> super returns [a proxy to] the *next* class in the MRO chain; it may or ?
> may not be a superclass of C (it may be a sibling class instead).

It could be even a niece class.


Carl Banks


From sato.photo at gmail.com  Wed Jul  1 01:38:04 2009
From: sato.photo at gmail.com (sato.photo at gmail.com)
Date: Tue, 30 Jun 2009 22:38:04 -0700 (PDT)
Subject: Basic question from pure beginner
Message-ID: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>

I have been going through some Python Programming exercises while
following the MIT OpenCourseWare Intro to CS syllabus and am having
some trouble with the first "If" exercise listed on this page:

http://en.wikibooks.org/wiki/Python_Programming/Conditional_Statements#If_Exercises

I have been able to make the module quit after entering a password
three times, but can't get it to quit right away after the correct one
is entered.  I know this is really basic, please forgive me.  I have
no programming experience and have just started going through these
tutorials.

My code is here:

http://python.pastebin.com/m6036b52e

-daniel


From pavlovevidence at gmail.com  Wed Jul  1 02:04:15 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 30 Jun 2009 23:04:15 -0700 (PDT)
Subject: Making code run in both source tree and installation path
References: <mailman.2310.1246292443.8015.python-list@python.org>
Message-ID: <5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>

On Jun 29, 9:20?am, Javier Collado <javier.coll... at gmail.com> wrote:
> I've seen different approaches:
> - distutils trick in setup.py to modify the installed script (i.e.
> changing a global variable value) so that it has a reference to the
> data files location.


One of my biggest complaints about distutils is that it doesn't do
this, a limitation made worse by the fact that distutils allows you to
specify an alternate data file directory, but your scripts have no way
to know what that alternate directory is installed.  Which really
limits the usefulness of that functionality.

The most common way I've seen people work around this issue is to
throw their data files into the package directories.  Yuck.

At one point I hacked up a setup.py file to look in the distutils data
structure and pull out the data install location, and wrote out a
trivial python file listing that location.  (The distutils build data
structure is helpfully returned by setup function.)  I never felt good
about it, and it wouldn't work if the install was done in steps (such
as build as user, install as superuser).

If you care to navigate the murky internals of distutils to do this in
a more elegant way, more power to you, and if so I'd recommend doing
it that way.


> - Heuristic in the package code to detect when it's being executed
> from the source tree and when it has been the installed
> - Just using an environment variable that the user must set according
> to his needs

I guess I'd combine these two.  Make a sensible guess about where the
data files are by checking out the environment, but if the data files
aren't there (such as if the user installs to a different data
location) then they are responsible for setting an env variable or
config option.



> I guess that there are other options, for example, maybe using
> buildout. What would you say it's the best/more elegant option to
> solve this problem?

Another option is not to use distutils at all.  If you are writing an
application, I think that would be a good idea.  I don't think
applications really need to be located in site-packages.

If you have any C-extensions it might complicate this.


Carl Banks


From __peter__ at web.de  Wed Jul  1 03:01:44 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 01 Jul 2009 09:01:44 +0200
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
Message-ID: <h2f1kk$e9m$03$1@news.t-online.com>

sato.photo at gmail.com wrote:

> I have been going through some Python Programming exercises while
> following the MIT OpenCourseWare Intro to CS syllabus and am having
> some trouble with the first "If" exercise listed on this page:
> 
> 
http://en.wikibooks.org/wiki/Python_Programming/Conditional_Statements#If_Exercises
> 
> I have been able to make the module quit after entering a password
> three times, but can't get it to quit right away after the correct one
> is entered.  I know this is really basic, please forgive me.  I have
> no programming experience and have just started going through these
> tutorials.
> 
> My code is here:
> 
> http://python.pastebin.com/m6036b52e
> 
> -daniel

Some hints: 

(1) Have the while loop check for both the correct password and the number 
of tries. Pseudocode:

while <more tries allowed> and <password not entered correctly>:
   ...

(2) After the loop has terminated you can check whether the password was 
entered correctly and print the appropriate message.

Aside: you can't mix if...else with other statements

correct:

if cond:
   print "sunny"
else:
   print "cloudy"
print "weather"

wrong: 

if cond:
   print "norwegian"
print "blue" 
else: # syntax error, else must immediately follow the indented if-block:
   print "moon"

you could fix it like so:

if cond:
   print "norwegian"
print "blue"
if not cond:
    print "moon"

Peter



From wuwei23 at gmail.com  Wed Jul  1 03:06:38 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 00:06:38 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
Message-ID: <b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>

On Jul 1, 3:38?pm, "sato.ph... at gmail.com" <sato.ph... at gmail.com>
wrote:
> I have been able to make the module quit after entering a password
> three times, but can't get it to quit right away after the correct one
> is entered. ?

Not with the code you pasted, you haven't. There's a missing colon on
line 7 & line 9 isn't indented properly. It's always best if we're
referring to the same source when trying to help with a problem.

The problem you're having, though, has to do with the while loop and
the fact that it's only checking one condition: has the 'count'
counter been incremented to 3. What you need to do is _also_ check for
the success condition:

is_confirmed = False
while count != 3 or is_confirmed:
  guess = raw_input("Enter your password: ")
  guess = str(guess)
  if guess != password:
    print "Access Denied"
    count = count + 1
  else:
    print "Password Confirmed"
    is_confirmed = True

This also provides you with a nice boolean that shows whether or not
the password was confirmed, which may be useful for latter code.

However, whenever you want to loop a set number of times, it's usually
better to use a 'for' loop instead:

PASSWORD = 'qwerty'
MAXRETRY = 3
for attempt in xrange(MAXRETRY):
  guess = str(raw_input('Enter your password: '))
  is_complete = guess == PASSWORD
  if is_complete:
    print 'Password confirmed'
    break # this exits the for loop
  else:
    print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)

This saves you from the burden of creating, incrementing & testing
your own counter.

If there's anything here that isn't clear, please don't hesitate to
ask.


From sato.photo at gmail.com  Wed Jul  1 03:58:27 2009
From: sato.photo at gmail.com (sato.photo at gmail.com)
Date: Wed, 1 Jul 2009 00:58:27 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>
Message-ID: <49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>

Thank you for all of the help.  With your assistance and help from the
Python Tutor mailing list I was able to come up with the following
code:

password = "qwerty"
correct_password_given = False
guess = "0"
count = 0
while count != 3 and not correct_password_given :
   guess = raw_input("Enter your password: ")
   guess = str(guess)
   if guess != password:
       print "Access Denied"
       count = count + 1
   else:
       print "Password Confirmed"
       correct_password_given = True


If I understand it correctly, the function will continue to loop until
either the count == 3 or until correct_password_give = True,
satisfying the two conditions of the assignment, which were to lock a
user out after three failed password attempts and to print "Access
Granted" and end the module if the correct password is given.  Am I
understanding this correctly?

Thanks!

On Jul 1, 12:06?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 1, 3:38?pm, "sato.ph... at gmail.com" <sato.ph... at gmail.com>
> wrote:
>
> > I have been able to make the module quit after entering a password
> > three times, but can't get it to quit right away after the correct one
> > is entered. ?
>
> Not with the code you pasted, you haven't. There's a missing colon on
> line 7 & line 9 isn't indented properly. It's always best if we're
> referring to the same source when trying to help with a problem.
>
> The problem you're having, though, has to do with the while loop and
> the fact that it's only checking one condition: has the 'count'
> counter been incremented to 3. What you need to do is _also_ check for
> the success condition:
>
> is_confirmed = False
> while count != 3 or is_confirmed:
> ? guess = raw_input("Enter your password: ")
> ? guess = str(guess)
> ? if guess != password:
> ? ? print "Access Denied"
> ? ? count = count + 1
> ? else:
> ? ? print "Password Confirmed"
> ? ? is_confirmed = True
>
> This also provides you with a nice boolean that shows whether or not
> the password was confirmed, which may be useful for latter code.
>
> However, whenever you want to loop a set number of times, it's usually
> better to use a 'for' loop instead:
>
> PASSWORD = 'qwerty'
> MAXRETRY = 3
> for attempt in xrange(MAXRETRY):
> ? guess = str(raw_input('Enter your password: '))
> ? is_complete = guess == PASSWORD
> ? if is_complete:
> ? ? print 'Password confirmed'
> ? ? break # this exits the for loop
> ? else:
> ? ? print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
>
> This saves you from the burden of creating, incrementing & testing
> your own counter.
>
> If there's anything here that isn't clear, please don't hesitate to
> ask.



From bruno.42.desthuilliers at websiteburo.invalid  Wed Jul  1 04:06:21 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 10:06:21 +0200
Subject: Learning to use decorators with classes
In-Reply-To: <mailman.2389.1246374159.8015.python-list@python.org>
References: <mailman.2389.1246374159.8015.python-list@python.org>
Message-ID: <4a4b18f2$0$15174$426a74cc@news.free.fr>

sk8in_zombi at yahoo.com.au a ?crit :
> --- On Tue, 30/6/09, Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> wrote:
> 
(snip)
>>
>> This can't work, and it's a FAQ FWIW - but since there's no
>> official c.l.py FAQ, we won't hold it against you !-)
>>
> 
> Can you please point me to the FAQ related to this snippet. I would be grateful.

Well, as I said, there's *no* c.l.py FAQ (I mean, any half-official text 
document listing frequently asked questions and their canonical 
answers), so I just can't provide any pointer here :-/

I guess we all here love talking about Python (and showing out our 
science, knowledge and wisdom) too much to maintain a FAQ !-)

(snip)



From bruno.42.desthuilliers at websiteburo.invalid  Wed Jul  1 04:26:16 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 10:26:16 +0200
Subject: Basic question from pure beginner
In-Reply-To: <49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
Message-ID: <4a4b1d9d$0$1525$426a74cc@news.free.fr>

sato.photo at gmail.com a ?crit :
> Thank you for all of the help.  With your assistance and help from the
> Python Tutor mailing list I was able to come up with the following
> code:
> 
> password = "qwerty"
> correct_password_given = False
> guess = "0"

You could just use None here:

   guess=None


> count = 0
> while count != 3 and not correct_password_given :
>    guess = raw_input("Enter your password: ")
>    guess = str(guess)

IIRC, raw_input() already returns a string !-)

>    if guess != password:
>        print "Access Denied"
>        count = count + 1

Or:
          count += 1

>    else:
>        print "Password Confirmed"
>        correct_password_given = True
> 
> 
> If I understand it correctly, the function will continue to loop until
> either the count == 3 or until correct_password_give =  True,

There are many ways to write a same boolean test, and some are easier to 
understand. Your test could be written:

   while not (count == 3 or correct_password_given) :
      # proceed

Does it answer your question ?-)

As a general rule:

* not A and not B <=> not (A or B)
* not A or not B  <=> not (A and B)


> satisfying the two conditions of the assignment, which were to lock a
> user out after three failed password attempts and to print "Access
> Granted" and end the module if the correct password is given.

Well, given your snippet, execution indeed terminates after either 
successful 'login' or 3 failed attempts, but that's mostly because 
there's no code to execute after the while loop...



From mr.spoon21 at gmail.com  Wed Jul  1 04:33:28 2009
From: mr.spoon21 at gmail.com (Mr.SpOOn)
Date: Wed, 1 Jul 2009 10:33:28 +0200
Subject: Getting input the scanf way
Message-ID: <8f67b6f80907010133t7f6e2d9eg9ffa3b927d540728@mail.gmail.com>

Hi,
I need to do some kind of interactive command line program.

I mean: I run the program, it asks me for input, I type something and
then I get the output or other questions.
I'm not sure what is the right way to achieve this.

Thanks,
Carlo


From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:33:45 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:33:45 +1200
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org>
	<Xf-dnUHy7ad9rtTXnZ2dnUVZ_rSdnZ2d@pdx.net>
	<b1d86eff-c1a6-45b7-9784-9137f5e1c2a2@f33g2000vbm.googlegroups.com>
Message-ID: <h2f719$njc$4@lust.ihug.co.nz>

In message <b1d86eff-
c1a6-45b7-9784-9137f5e1c2a2 at f33g2000vbm.googlegroups.com>, ryles wrote:

> On Jun 29, 5:43 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>
>>and I personally wouldn't have it any other way.  Simulating a shell
>> with hooks on its I/O should be so complicated that a "script kiddie"
>> has trouble writing a Trojan.
> 
> +1 QOTW

Trouble is, script kiddies, by definition, don't need to write anything. 
They just need to download something somebody else has already written.

-- 
Lawrence "I counter your +1 with my -1" D'Oliveiro



From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:39:06 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:39:06 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
Message-ID: <h2f7ba$njc$5@lust.ihug.co.nz>

In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o 
Valverde wrote:

> Simple example usage case: Insert string into data structure in sorted
> order if it doesn't exist, else retrieve it.

    the_set = set( ... )

    if str in the_set :
        ... "retrieval" case ...
    else :
        the_set.add(str)
    #end if

Want sorted order?

    sorted(tuple(the_set))

What could be simpler?



From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:40:19 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:40:19 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com> <4A4462E6.7080700@netcabo.pt>
	<50697b2c0906252323y60c237d0i44725e841ad29ed5@mail.gmail.com>
	<mailman.2144.1245999295.8015.python-list@python.org>
Message-ID: <h2f7dj$njc$6@lust.ihug.co.nz>

In message <mailman.2144.1245999295.8015.python-list at python.org>, Miles 
Kaufmann wrote:

> On Jun 26, 2009, at 2:23 AM, Chris Rebert wrote:
> 
>> That's pretty much the bisect module in a nutshell. It manipulates a
>> sorted list using binary search.
> 
> With O(n) insertions and removals, though.  A decent self-balancing
> binary tree will generally do those in O(log n).

For values of n below, say, a million, would you even notice the difference 
on modern hardware?



From http  Wed Jul  1 04:42:42 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 01:42:42 -0700
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
Message-ID: <7xeit0iykd.fsf@ruckus.brouhaha.com>

Joachim Str?mbergson <Joachim at Strombergson.com> writes:
> http://docs.python.org/library/hashlib.html
> I would suggest to use the SHA-256 in the library.

I agree with this.  We should even move towards supporting x509 and/or
gpg signatures in eggs, similar to signed .jar files.


From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:43:10 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:43:10 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<11eb0a6e-4e21-4a61-bf46-4221fd75dc8d@v15g2000prn.googlegroups.com>
	<mailman.2146.1246002542.8015.python-list@python.org>
Message-ID: <h2f7iv$njc$7@lust.ihug.co.nz>

In message <mailman.2146.1246002542.8015.python-list at python.org>, Jo?o Valverde wrote:

> But a dict can't be used to implement a (sorted) table ADT.

for key in sorted(the_dict.keys(), cmp = ... whatever ordering criteria you like ...) :
    ... do something with the_dict[key] ...
#end for




From R.Brodie at rl.ac.uk  Wed Jul  1 04:43:40 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Wed, 1 Jul 2009 09:43:40 +0100
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
Message-ID: <h2f7jt$j33$1@south.jnrs.ja.net>


"Joachim Str?mbergson" <Joachim at Strombergson.com> wrote in message 
news:mailman.2422.1246418400.8015.python-list at python.org...

> Even so, choosing md5 in 2009 for something that (hopefully) will be
> used in years is a bad design decision. It creates a dependency for to
> an algorithm that all sensible recommendations point you to move away
> from.

Why not write the field as algorithm:value?

e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4

Installers can fallback to using hashlib.new(), so you can plug in a new
algorithm without changing the PEP or the installer code. 




From http  Wed Jul  1 04:43:49 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 01:43:49 -0700
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com> <4A4462E6.7080700@netcabo.pt>
	<50697b2c0906252323y60c237d0i44725e841ad29ed5@mail.gmail.com>
	<mailman.2144.1245999295.8015.python-list@python.org>
	<h2f7dj$njc$6@lust.ihug.co.nz>
Message-ID: <7xab3oiyii.fsf@ruckus.brouhaha.com>

Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> writes:
> > With O(n) insertions and removals, though.  A decent self-balancing
> > binary tree will generally do those in O(log n).
> 
> For values of n below, say, a million, would you even notice the difference 
> on modern hardware?

Huh?  Yes, of course you'd notice, unless you were doing the operation
just once or something like that.


From http  Wed Jul  1 04:47:34 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 01:47:34 -0700
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
Message-ID: <7x3a9gdc2h.fsf@ruckus.brouhaha.com>

"Richard Brodie" <R.Brodie at rl.ac.uk> writes:
> Why not write the field as algorithm:value?
> e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4

This is reasonable, though I would deprecate md5 and sha1 already, and
start with sha256.


From iainking at gmail.com  Wed Jul  1 05:52:24 2009
From: iainking at gmail.com (Iain King)
Date: Wed, 1 Jul 2009 02:52:24 -0700 (PDT)
Subject: string character count
References: <58ceecd5-6d2c-44a9-8ef9-01feac5792f4@b9g2000yqm.googlegroups.com>
Message-ID: <b3f73ed0-b9cc-4052-a509-082398ffe8b2@i6g2000yqj.googlegroups.com>

On Jun 30, 6:27?pm, noydb <jenn.du... at gmail.com> wrote:
> If I have a string for a file name such that I want to find the number
> of characters to the left of the dot, how can that be done?
>
> I did it this way:
> x = "text12345.txt"
> dot = x.find('.')
> print dot
>
> Was curious to see what method others would use - helps me learn. ?I
> guess I was most curious to see if it could be done in one line.
>
> And, how would a char count be done with no dot -- like if the string
> were "textstringwithoutdot" or "no dot in text string"?

import os
root, ext = os.path.splitext(x)
print len(root)

or in one line (assuming you've imported os):
print len(os.path.splitext(x)[0])


Iain


From pm567426 at gmail.com  Wed Jul  1 06:00:32 2009
From: pm567426 at gmail.com (Pedram)
Date: Wed, 1 Jul 2009 03:00:32 -0700 (PDT)
Subject: A question about fill_free_list(void) function
Message-ID: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>

Hello community,
I'm reading the CPython interpreter source code,
first, if you have something that I should know for better reading
this source code, I would much appreciate that :)
second, in intobject.c file, I read the following code in
fill_free_list function that I couldn't understand:
<code>while (--q > p)
    Py_TYPE(q) = (struct _typeobject *)(q-1);
Py_TYPE(q) = NULL;
</code>
What does it mean?

Thanks.


From jerome.fuselier at gmail.com  Wed Jul  1 06:14:20 2009
From: jerome.fuselier at gmail.com (=?ISO-8859-1?Q?J=E9r=F4me_Fuselier?=)
Date: Wed, 1 Jul 2009 03:14:20 -0700 (PDT)
Subject: Problem with uuid package when embedding a python interpreter
References: <7d5cfbf0-38d5-4505-a93a-f321d0da74b8@c36g2000yqn.googlegroups.com>
	<mailman.2404.1246384974.8015.python-list@python.org>
Message-ID: <becd98c7-c486-4e29-aa75-88767c30e27c@l5g2000vbp.googlegroups.com>

On Jun 30, 7:02?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Tue, 30 Jun 2009 13:05:42 -0300, J?r?me Fuselier
> <jerome.fusel... at gmail.com> escribi?:
>
>
>
> > ? I've tried to import a script in an embedded python intrepreter but
> > this script fails when it imports the uuid module. I have a
> > segmentation fault in Py_Finalize().
>
> > #include "Python.h"
>
> > void test() {
> > ? ? Py_Initialize();
> > ? ? PyImport_Import(PyString_FromString("uuid"));
> > ? ? Py_Finalize();
> > }
>
> > main(int argc, char **argv)
> > {
> > ? ? for (i=0 ; i < 10; i++)
> > ? ? ? ? test();
> > }
>
> > For my application, I have to call Py_initialize and Py_Finalize
> > several times so factorizing them in the main function is not an easy
> > solution for me.
>
> Are you sure you can't do that? Not even using Py_IsInitialized? Try to
> avoid repeatedly calling Py_Initialize - won't work.
>
> Python 2.x does not have a way to "un-initialize" an extension module
> (that's a big flaw in Python design). Modules that contain global state
> are likely to crash the interpreter when used by the second time. (Python
> 3 attempts to fix that)
>
> --
> Gabriel Genellina

Hi Gabriel,
  Thanks for your response. I can modify my code to call
Py_IsInitialized which I didn't know before and this works well. The
problem is that I did not own the process which calls Py_Initialize
and Py_Finalize. I'm able to call Py_Initialize correctly but I can't
call Py_Finalize so this is not perfect.

At least I have a temporary solution which is not too bad.
Thanks,
Jerome


From jeanmichel at sequans.com  Wed Jul  1 06:33:43 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 01 Jul 2009 12:33:43 +0200
Subject: string character count
In-Reply-To: <4A4A51D7.6040602@mrabarnett.plus.com>
References: <58ceecd5-6d2c-44a9-8ef9-01feac5792f4@b9g2000yqm.googlegroups.com>
	<4A4A51D7.6040602@mrabarnett.plus.com>
Message-ID: <4A4B3B87.5040703@sequans.com>

MRAB wrote:
> noydb wrote:
>> If I have a string for a file name such that I want to find the number
>> of characters to the left of the dot, how can that be done?
>>
>> I did it this way:
>> x = "text12345.txt"
>> dot = x.find('.')
>> print dot
>>
>> Was curious to see what method others would use - helps me learn.  I
>> guess I was most curious to see if it could be done in one line.
>>
> >>> print "text12345.txt".find('.')
> 9
>
>> And, how would a char count be done with no dot -- like if the string
>> were "textstringwithoutdot" or "no dot in text string"?
>
> If there's no dot then find() returns -1.
>
> If you wanted to know the number of characters before the dot, if
> present, or in total otherwise, then you could use split():
>
> >>> len("text12345.txt".split(".", 1)[0])
> 9
> >>> len("textstringwithoutdot".split(".", 1)[0])
> 20
>

You may have problems with files containing multiple dots.
the os module provide nice & safe methods to parse a file path (on any 
system, mac os windows, linux).

 >>>f = "/dir1/dir2/test.log"
 >>>os.path.splitext(f)
('/dir1/dir2/test', '.log')

 >>>os.path.splitext(os.path.basename(f))
('test', '.log')

 >>>f2 = 'test.log'
 >>>os.path.splitext(os.path.basename(f2))
('test', '.log')



one safe way would be then
 >>> import os
 >>> x = "text12345.txt"
 >>> base , ext = os.path.splitext(os.path.basename(x))
 >>> print len(base)
9

Jean-Michel


From icanbob at gmail.com  Wed Jul  1 06:40:22 2009
From: icanbob at gmail.com (bobicanprogram)
Date: Wed, 1 Jul 2009 03:40:22 -0700 (PDT)
Subject: Passing parameters for a C program in Linux.
References: <7fa13d0c-d031-4576-8fee-a1c84af3e265@y7g2000yqa.googlegroups.com>
Message-ID: <eee0d931-fc6f-46fa-bb1f-1fd86242f126@b9g2000yqm.googlegroups.com>

On Jun 30, 6:46 am, "venutaurus... at gmail.com"
<venutaurus... at gmail.com> wrote:
> Hi all,
>        I have to write an automted script which will test my c
> program. That program when run will ask for the commands. For example:
>
> local-host# ./cli
> Enter 1 for add
> Enter 2 for sub
> Enter 3 for mul
> 1            -------Our option
> Enter two numbers
> 44 33  -------- Our option
> Result is 77
>
> As shown in the above example it lists all the options and waits for
> user input and once given, it does some operations and waits for some
> more. This has to be automated.
>
> Can someone give suggestions how to do this in Python (Linux Platform
> in particular).
>
> Thank you,
> Venu.


Take a look at the examples here:

http://www.icanprogram.com/06py/main.html

You can probably do what you want using the SIMPL toolkit quite
easily.

bob


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  1 07:41:07 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 01 Jul 2009 11:41:07 GMT
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <025b3cfd$0$20654$c3e8da3@news.astraweb.com>

On Wed, 01 Jul 2009 20:39:06 +1200, Lawrence D'Oliveiro wrote:

> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o
> Valverde wrote:
> 
>> Simple example usage case: Insert string into data structure in sorted
>> order if it doesn't exist, else retrieve it.
> 
>     the_set = set( ... )
> 
>     if str in the_set :
>         ... "retrieval" case ...

Not terribly useful, because there's no way of attaching any data to 
retrieve to the key. Apart from the case of interning strings (or other 
keys), you'd probably want a dict rather than a set:

if str in the_dict:
    return the_dict[str]
else:
    the_dict[str] = something_or_other


>     else :
>         the_set.add(str)
>     #end if


> Want sorted order?
> 
>     sorted(tuple(the_set))
> 
> What could be simpler?

Dropping the entirely superfluous creation of a tuple:

sorted(the_set)

That's a reasonable approach for small sets of data, but it isn't very 
useful if the_set contains 4GB of keys, because you have to duplicate the 
keys, then sort them. More effective would be a data structure that was 
always sorted. This has the further advantage that it's even simpler than 
sorted(the_set):

the_set



-- 
Steven


From magawake at gmail.com  Wed Jul  1 07:41:29 2009
From: magawake at gmail.com (Mag Gam)
Date: Wed, 1 Jul 2009 07:41:29 -0400
Subject: Multi thread reading a file
In-Reply-To: <op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <1cbd6f830907010441l3f953d13r6dd4e1a55dedc806@mail.gmail.com>

Thanks for the response Gabriel.



On Wed, Jul 1, 2009 at 12:54 AM, Gabriel
Genellina<gagsl-py2 at yahoo.com.ar> wrote:
> En Tue, 30 Jun 2009 22:52:18 -0300, Mag Gam <magawake at gmail.com> escribi?:
>
>> I am very new to python and I am in the process of loading a very
>> large compressed csv file into another format. ?I was wondering if I
>> can do this in a multi thread approach.
>
> Does the format conversion involve a significant processing time? If not,
> the total time is dominated by the I/O time (reading and writing the file)
> so it's doubtful you gain anything from multiple threads.

The format does inolve significant time processing each line.
>
>> Here is the pseudo code I was thinking about:
>>
>> Let T ?= Total number of lines in a file, Example 1000000 (1 million
>> files)
>> Let B = Total number of lines in a buffer, for example 10000 lines
>>
>>
>> Create a thread to read until buffer
>> Create another thread to read buffer+buffer ?( So we have 2 threads
>> now. But since the file is zipped I have to wait until the first
>> thread is completed. Unless someone knows of a clever technique.
>> Write the content of thread 1 into a numpy array
>> Write the content of thread 2 into a numpy array
>
> Can you process each line independently? Is the record order important? If
> not (or at least, some local dis-ordering is acceptable) you may use a few
> worker threads (doing the conversion), feed them thru a Queue object, put
> the converted lines into another Queue, and let another thread write the
> results onto the destination file.

Yes, each line can be independent. The original file is a time series
file which I am placing it into a Numpy array therefore I don't think
the record order is important.  The writing is actually done when I
place a value into a "dset" object.


Let me show you what I mean.
reader=csv.reader(open("100000.csv"))
for s,row in enumerate(reader):
 if s!=0 and s%bufsize==0:
      dset[s-bufsize:s] = t  #here is where I am writing the data to
the data structure. Using a range or broadcasting.

  #15 columns
 if len(row) != 15:
   break

 t[s%bufsize] = tuple(row)

#Do this all the way at the end for flushing.
if (s%bufsize != 0):
   dset[(s//bufsize)*bufsize:s]=t[0:s%bufsize]












>
> import Queue, threading, csv
>
> def convert(in_queue, out_queue):
> ?while True:
> ? ?row = in_queue.get()
> ? ?if row is None: break
> ? ?# ... convert row
> ? ?out_queue.put(converted_line)
>
> def write_output(out_queue):
> ?while True:
> ? ?line = out_queue.get()
> ? ?if line is None: break
> ? ?# ... write line to output file
>
> in_queue = Queue.Queue()
> out_queue = Queue.Queue()
> tlist = []
> for i in range(4):
> ?t = threading.Thread(target=convert, args=(in_queue, out_queue))
> ?t.start()
> ?tlist.append(t)
> output_thread = threading.Thread(target=write_output, args=(out_queue,))
> output_thread.start()
>
> with open("...") as csvfile:
> ?reader = csv.reader(csvfile, ...)
> ?for row in reader:
> ? ?in_queue.put(row)
>
> for t in tlist: in_queue.put(None) # indicate end-of-work
> for t in tlist: t.join() # wait until finished
> out_queue.put(None)
> output_thread.join() # wait until finished
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From ganesh.gbg at gmail.com  Wed Jul  1 07:48:11 2009
From: ganesh.gbg at gmail.com (gganesh)
Date: Wed, 1 Jul 2009 04:48:11 -0700 (PDT)
Subject: what will be best framework to select to develop Multi-Level 
	Marketing (network marketing) application in python?
Message-ID: <2f8c1642-6cad-4cd1-bc97-60c16aea31fd@g6g2000vbr.googlegroups.com>

hi group,
I have to build a software for Multi-Level Marketing (network
marketing),There are several Frameworks available in python ,i could
like to know the best Framework suitable to develop an application on
Multi-Level Marketing .
Thanks


From Ron.Barak at lsi.com  Wed Jul  1 07:48:40 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Wed, 1 Jul 2009 12:48:40 +0100
Subject: What are the limitations of cStringIO.StringIO() ?
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>

Hi,

I think I'm up against a limitation in cStringIO.StringIO(), but could not find any clues on the web, especially not in http://docs.python.org/library/stringio.html.

What I have is the following function:

    def concatenate_files(self,filename_array):
        import types

        f = cStringIO.StringIO()
        for filename in filename_array:
            log_stream = LogStream(filename)
            if not isinstance(log_stream, types.NoneType):
                try:
                    string_ = log_stream.input_file.read()
                except AttributeError, e:
                        sys.stderr.write("AttributeError: "+str(e)+"\n")
                        sys.stderr.write("log_stream: "+str(log_stream)+"\n")
            else:
                return(None)

            f.write(string_)
        return (f)

And, when the list of files - in filename_array - is pointing to long/large enough files, I get the exception:

Traceback (most recent call last):
  File "svm_ts_tool_in_progress.py", line 244, in OnSelectCell
    self.InspectorViewController(row,col)
  File "svm_ts_tool_in_progress.py", line 1216, in InspectorViewController
    self.InspectorePaneGetRecords(self.req_table, rec)
  File "svm_ts_tool_in_progress.py", line 1315, in InspectorePaneGetRecords
    log_stream = ConcatenatedLogStream(self.events_dict[req_table]["db_dict"].keys())
  File "c:\Documents and Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 31, in __init__
    self.input_file = self.concatenate_files(filename_array)
  File "c:\Documents and Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 47, in concatenate_files
    string_ = log_stream.input_file.read()
MemoryError

 1.  Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
 2.  Could you suggest a better way to create a string that contains the concatenation of several big files ?

Thanks,
Ron.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/7a56bd37/attachment.html>

From thomas.bugzilla at gmx.net  Wed Jul  1 08:38:36 2009
From: thomas.bugzilla at gmx.net (Thomas)
Date: Wed, 01 Jul 2009 14:38:36 +0200
Subject: infinite recursion in pickle.load()
Message-ID: <h2fld6$2n4$1@news.web.de>

we regularly pickle and unpickle data from the same script (mostly 
dictionaries).

sometimes, a file written this way cannot be unpickled with 
pickle.load(), due to an infinite recursion with __getattr__ in 
codecs.py. here is a python2.5 stack trace excerpt:

/usr/local/lib/python2.5/pickle.py in load(file)
    1403
    1404 def load(file):
-> 1405     return Unpickler(file).load()
    1406
    1407 def loads(str):

/usr/local/lib/python2.5/pickle.py in load(self)
     891             while 1:
     892                 key = read(1)
--> 893                 dispatch[key](self)
     894         except _Stop, stopinst:
     895             return stopinst.value

/usr/local/lib/python2.5/pickle.py in load_build(self)
    1248         state = stack.pop()
    1249         inst = stack[-1]
-> 1250         setstate = getattr(inst, "__setstate__", None)
    1251         if setstate:
    1252             setstate(state)

/usr/local/lib/python2.5/codecs.py in __getattr__(self, name, getattr)
     328         """ Inherit all other methods from the underlying stream.
     329         """
--> 330         return getattr(self.stream, name)
     331
     332     def __enter__(self):

/usr/local/lib/python2.5/codecs.py in __getattr__(self, name, getattr)
     328         """ Inherit all other methods from the underlying stream.
     329         """
--> 330         return getattr(self.stream, name)
     331
     332     def __enter__(self):

     ...

The last frame repeats ad infinitum.

'inst' in the third frame is a <StreamWriter instance at 839b62c>

The problem is the same with cPickle.

This looks somewhat related to this Python issue, which is only about 
the exception reporting:
http://bugs.python.org/issue5508
(The title of the issue is the error you get when running our code in 
python2.6).

Any idea how to go about that?

T.


From gil.shinar at gmail.com  Wed Jul  1 08:56:12 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Wed, 1 Jul 2009 05:56:12 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
Message-ID: <794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>

On Jun 30, 7:48?pm, s... at pobox.com wrote:
> ? ? Gil> I have looked for a timeout parameter to limit the 4 minutes to
> ? ? Gil> something more reasonable but couldn't find one. ?Can anyone please
> ? ? Gil> help?
>
> ? ? Gil> BTW, I'm using Sybase.connect(<DBS name>, <Username>, <Password>,
> ? ? Gil> datetime='auto')
>
> We use the Sybase module where I work, but I've never encountered this
> problem (or a timeout parameter of any kind). ?At any rate, you'll probably
> have more luck asking on the python-sybase mailing list:
>
> ? ? python-sybase-m... at lists.sourceforge.net
>
> --
> Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> ? ? when i wake up with a heart rate below 40, i head right for the espresso
> ? ? machine. -- chaos @ forums.usms.org

Are you saying, that when you trying to connect to a sybase DBS server
and the DBS or the server is down, you get an error after a few
seconds and not after a few minutes? Which python version are you
using?

I'll try to ask in the python-sybase mailing list

Thanks


From gil.shinar at gmail.com  Wed Jul  1 09:08:01 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Wed, 1 Jul 2009 06:08:01 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
Message-ID: <5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com>

On Jul 1, 3:56?pm, eranlevi <gil.shi... at gmail.com> wrote:
> On Jun 30, 7:48?pm, s... at pobox.com wrote:
>
>
>
> > ? ? Gil> I have looked for a timeout parameter to limit the 4 minutes to
> > ? ? Gil> something more reasonable but couldn't find one. ?Can anyone please
> > ? ? Gil> help?
>
> > ? ? Gil> BTW, I'm using Sybase.connect(<DBS name>, <Username>, <Password>,
> > ? ? Gil> datetime='auto')
>
> > We use the Sybase module where I work, but I've never encountered this
> > problem (or a timeout parameter of any kind). ?At any rate, you'll probably
> > have more luck asking on the python-sybase mailing list:
>
> > ? ? python-sybase-m... at lists.sourceforge.net
>
> > --
> > Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> > ? ? when i wake up with a heart rate below 40, i head right for the espresso
> > ? ? machine. -- chaos @ forums.usms.org
>
> Are you saying, that when you trying to connect to a sybase DBS server
> and the DBS or the server is down, you get an error after a few
> seconds and not after a few minutes? Which python version are you
> using?
>
> I'll try to ask in the python-sybase mailing list
>
> Thanks

There's no such group as python-sybase :-(

Thanks


From pm567426 at gmail.com  Wed Jul  1 09:50:31 2009
From: pm567426 at gmail.com (Pedram)
Date: Wed, 1 Jul 2009 06:50:31 -0700 (PDT)
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
Message-ID: <dba78c8e-320e-4e19-a33b-f1d830de09d5@f10g2000vbf.googlegroups.com>

Oh... I got it! :)
I found this line in ctypes.h:
#define Py_TYPE(q) = ((PyObject *)(q))->ob_next;
So those lines are trying to set the blocks type from rear to front.

But I still don't know why after the while (when q is equal to p), the
Py_TYPE(q) set to NULL!


From sebastian.schabe at gmx.de  Wed Jul  1 10:51:47 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Wed, 01 Jul 2009 16:51:47 +0200
Subject: deleting certain entries in numpy array
Message-ID: <4a4b7763$1@news.fhg.de>

Hello everybody,

I'm new to python and numpy and have a little/special problem:

I have an numpy array which is in fact a gray scale image mask, e.g.:

mask =
array([[  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0, 255, 255, 255,   0,   0, 255,   0],
        [  0,   0, 255, 255, 255,   0,   0, 255,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0]], dtype=uint8)

and I have another array of (y, x) positions in that mask (first two 
values of each row):

pos =
array([[  3.,   2.,   0.,   0.],
        [  3.,   4.,   0.,   0.],
        [  5.,   2.,   0.,   0.],
        [  5.,   4.,   0.,   0.],
        [  6.,   2.,   0.,   0.],
        [  6.,   7.,   0.,   0.],
        [  0.,   0.,   0.,   0.],
        [  8.,   8.,   0.,   0.]])

and now I only want to keep all lines from 2nd array pos with those 
indices that are nonzero in the mask, i.e. line 3-6 (pos[2]-pos[5]).

F.e. line 4 in pos has the values (5, 4) and mask[5][4] is nonzero, so I 
want to keep it. While line 2 (pos[1]) has the values (4, 6) and 
mask[4][6] is zero, so shall be discarded.

I want to avoid a for loop (if possible!!!) cause I think (but don't 
know) numpy array are handled in another way. I think numpy.delete is 
the right function for discarding the values, but I don't know how to 
build the indices.



Maybe someone can help me with that or suggest which way to do this

Sebastian


From Frank.Aune at broadpark.no  Wed Jul  1 11:02:20 2009
From: Frank.Aune at broadpark.no (Frank Aune)
Date: Wed, 1 Jul 2009 17:02:20 +0200
Subject: logging module and binary strings
Message-ID: <200907011702.21450.Frank.Aune@broadpark.no>

Hello,

---- snip ----
>>> import logging
>>> logging.basicConfig(level=logging.DEBUG)
>>> x='\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>> x
'\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>> print x
?????
>>> logging.info(x)
Traceback (most recent call last):
  File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
    stream.write(fs % msg.encode("UTF-8"))
UnicodeDecodeError: 'ascii' codec can't decode byte 0xfe in position 10: 
ordinal not in range(128)
>>> logging.info(x, extra={'encoding':'utf-8'})
Traceback (most recent call last):
  File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
    stream.write(fs % msg.encode("UTF-8"))
UnicodeDecodeError: 'utf8' codec can't decode byte 0xfe in position 10: 
unexpected code byte

---- snip ----

Is there any way to log the above value of x "properly" using the python 
logging module? By properly I mean logging the value displayed when entering 
just x in the python shell and pressing enter. 

Regards,
Frank




From eric.pruitt at gmail.com  Wed Jul  1 11:17:31 2009
From: eric.pruitt at gmail.com (Eric Pruitt)
Date: Wed, 1 Jul 2009 10:17:31 -0500
Subject: Bytes, Strings, Encoding
Message-ID: <171e8a410907010817j715f1d5ye638ea4b2469afd9@mail.gmail.com>

Hello,

I am working on the subprocess.Popen module for Python 2.7 and am now moving
my changes over to Python 3.1 however I am having trouble with the whole
byte situation and I can't quite seem to understand how to go back and forth
between bytes and strings. I am also looking for the Python 3k equivalent
for the Python 2.X built-in buffer class.

One version of the file with my modifications can be found here  <
http://code.google.com/p/subprocdev/source/browse/subprocess.py?spec=svn5b570f8cbfcaae859091eb01b21b183aa5221af9&r=5b570f8cbfcaae859091eb01b21b183aa5221af9>.
Lines 1 - 15 are me attempting to get around certain changes between
Python 3.0 and Python 2.7. Further down on line 916, we have the function
"send" and "recv" in which I am having the most trouble with bytes and
strings.

Any help is appreciated. Feel free to comment on my blog
http://subdev.blogspot.com/ or reply to the last.

Thanks in advance,
Eric
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/fa346a3a/attachment.html>

From Scott.Daniels at Acm.Org  Wed Jul  1 11:38:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 01 Jul 2009 08:38:58 -0700
Subject: invoking a method from two superclasses
In-Reply-To: <mailman.2423.1246419562.8015.python-list@python.org>
References: <mailman.8917.1246409702.8014.python-list@python.org>
	<mailman.2423.1246419562.8015.python-list@python.org>
Message-ID: <r6qdnZX9Do_xHNbXnZ2dnUVZ_hednZ2d@pdx.net>

 > Mitchell L Model wrote:

Sorry, after looking over some other responses, I went back and re-read
your reply.  I'm just making sure here, but:

 > Scott David Daniels wrote:
Below compressed for readability in comparison:
>>    class A:
>>        def __init__(self): super().__init__(); print('A')
>>    class B:
>>        def __init__(self): super().__init__(); print('B')
>>    class C(A, B):
>>        def __init__(self): super().__init__(); print('C')
>>    C()
>> And, if you are doing it with a message not available in object:

Renamed to disambiguate later discussion
>>    class root:
>>        def prints(self): print('root') # or pass if you prefer
>>    class D(root):
>>        def prints(self): super().prints(); print('D')
>>    class E(root):
>>        def prints(self): super().prints(); print('E')
>>    class F(D, E):
>>        def prints(self): super().prints(); print('F')
>>    F().prints()

> What I was missing is that each path up to and including the top of the diamond
> must include a definition of the method, along with super() calls to move the method
> calling on its way up.

Actually, not really true.  In the F through root example, any of the
"prints" methods except that on root may be deleted and the whole thing
works fine.  The rootward (closer to object) end must contain the method
in question, possibly only doing a pass as the action, and _not_ calling
super.  The other methods (those in D, E, and F above are all optional
(you can freely comment out those methods where you like), but each
should call super() in their bodies.

Note that you can also add a class:
     class G(E, D):
         def prints(self): super().prints(); print('G')
     G().prints()
Also note that the inheritances above can be "eventually inherits from"
as well as direct inheritance.

> Is this what the documentation means by "cooperative multiple inheritance"?

Yes, the phrase is meant to convey "No magic (other than super itelf) is
involved in causing the other methods to be invoked.  If you want "all"
prints methods called, make sure all but the last method do super calls.
Of course, any method that doesn't do the super call will be the last by
definition (no flow control then), but by putting the non-forwarding
version at or below the lower point of the diamond, the mro order
guarantees that you will have a "good" place to stop.

Think of the mro order as a solution to the partial order constraints
that a class must appear before any of its direct superclasses, and (by
implication) after any of its subclasses.

> If your correction of my example, if you remove super().__init__ from B.__init__
> the results aren't affected, because object.__init__ doesn't do anything and
> B comes after A in C's mro. However, if you remove super().__init__ from
> A.__init__, it stops the "supering" process dead in its tracks.

Removing the super from B.__init__ means that you don't execute
object.__init__.  It turns out that object does nothing in its __init__,
but without knowing that, removing the super from B.__init__ is also a
mistake.

So, you may well already have it all right, but as long as I'm putting
in the effort to get the "operational rules about using super" out, I
thought I'd fill in this last little bit.

--Scott David Daniels
Scott.Daniels at Acm.Org


From jenn.duerr at gmail.com  Wed Jul  1 11:45:40 2009
From: jenn.duerr at gmail.com (noydb)
Date: Wed, 1 Jul 2009 08:45:40 -0700 (PDT)
Subject: string character count
References: <58ceecd5-6d2c-44a9-8ef9-01feac5792f4@b9g2000yqm.googlegroups.com>
	<b3f73ed0-b9cc-4052-a509-082398ffe8b2@i6g2000yqj.googlegroups.com>
Message-ID: <54b554d3-c03e-40de-a02d-a176d0583cea@z28g2000vbl.googlegroups.com>

thanks everyone for all the ideas -- simple stuff, I know for you all,
but very helpful for me.


From jcd at sdf.lonestar.org  Wed Jul  1 11:48:23 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Wed, 01 Jul 2009 11:48:23 -0400
Subject: It's ...
In-Reply-To: <df0dea3d-691f-4f24-9a63-09fd59fbf229@b15g2000yqd.googlegroups.com>
References: <qjt4451snn47mr8qj3md1coi9a19tvt1v5@4ax.com>
	<mailman.2074.1245876142.8015.python-list@python.org>
	<df0dea3d-691f-4f24-9a63-09fd59fbf229@b15g2000yqd.googlegroups.com>
Message-ID: <1246463303.11768.0.camel@aalcdl07>

On Tue, 2009-06-30 at 13:24 -0700, Beni Cherniavsky wrote:
> On Jun 24, 11:40 pm, "J. Cliff Dyer" <j... at sdf.lonestar.org> wrote:
> > Also note that you can iterate over a file several times:
> >
> > f = open('foo.txt')
> > for line in f:
> >     print line[0]  # prints the first character of every line
> > for line in f:
> >     print line[1]  #prints the second character of every line
> >
> No, you can't.  The second loop prints nothing!
> A file by default advances forward.  Once you reach the end, you stay
> there.

You are, of course, absolutely right.  Sorry for the misinformation.

:(



From Scott.Daniels at Acm.Org  Wed Jul  1 11:49:31 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 01 Jul 2009 08:49:31 -0700
Subject: Multi thread reading a file
In-Reply-To: <mailman.2426.1246424006.8015.python-list@python.org>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
Message-ID: <dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>

Gabriel Genellina wrote:
> ...
> def convert(in_queue, out_queue):
>   while True:
>     row = in_queue.get()
>     if row is None: break
>     # ... convert row
>     out_queue.put(converted_line)

These loops work well with the two-argument version of iter,
which is easy to forget, but quite useful to have in your bag
of tricks:

     def convert(in_queue, out_queue):
         for row in iter(in_queue.get, None):
             # ... convert row
             out_queue.put(converted_line)

--Scott David Daniels
Scott.Daniels at Acm.Org


From petshmidt at googlemail.com  Wed Jul  1 12:05:37 2009
From: petshmidt at googlemail.com (someone)
Date: Wed, 1 Jul 2009 09:05:37 -0700 (PDT)
Subject: =?windows-1252?Q?getting_rid_of__=97?=
Message-ID: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>

Hello,

how can I replace '?' sign from string? Or do split at that character?
Getting unicode error if I try to do it:

UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
1: ordinal not in range(128)


Thanks, Pet

script is # -*- coding: UTF-8 -*-


From michele.simionato at gmail.com  Wed Jul  1 12:08:55 2009
From: michele.simionato at gmail.com (Michele Simionato)
Date: Wed, 1 Jul 2009 09:08:55 -0700 (PDT)
Subject: invoking a method from two superclasses
References: <mailman.8861.1246401585.8014.python-list@python.org> 
	<mailman.2416.1246408453.8015.python-list@python.org>
Message-ID: <8bc6afc1-21fc-40dd-ba7d-f0d549a7de93@24g2000yqm.googlegroups.com>

On Jul 1, 2:34?am, Mitchell L Model <MLMLi... at Comcast.net> wrote:
> I suspect we should have a Multiple Inheritance HOWTO, though details and
> recommendations would be controversial. I've accumulated lots of abstract
> examples along the lines of my question, using multiple inheritance both to
> create combination classes (the kinds that are probably best done with
> composition instead of inheritance) and mixins. I like mixins, and I like abstract
> classes. And yes I understand the horrors of working with a large component
> library that uses mixins heavily, because I've experienced many of them, going
> all the way back to Lisp-Machine Lisp's window system with very many combo
> classes such as FancyFontScrollingTitledMinimizableWindow, or whatever.
> Also, I understand that properties might be better instead of multiple inheritance
> for some situations. What I'm trying to do is puzzle out what the reasonable uses
> of multiple inheritance are in Python 3 and how classes and methods that follow
> them should be written.

You may be interest in my "Things to know about super":

http://www.artima.com/weblogs/viewpost.jsp?thread=236275
http://www.artima.com/weblogs/viewpost.jsp?thread=236278
http://www.artima.com/weblogs/viewpost.jsp?thread=237121


From robert.kern at gmail.com  Wed Jul  1 12:17:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 01 Jul 2009 11:17:31 -0500
Subject: Making code run in both source tree and installation path
In-Reply-To: <5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>
References: <mailman.2310.1246292443.8015.python-list@python.org>
	<5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>
Message-ID: <h2g26r$8lv$1@ger.gmane.org>

On 2009-07-01 01:04, Carl Banks wrote:
> On Jun 29, 9:20 am, Javier Collado<javier.coll... at gmail.com>  wrote:
>> I've seen different approaches:
>> - distutils trick in setup.py to modify the installed script (i.e.
>> changing a global variable value) so that it has a reference to the
>> data files location.
>
>
> One of my biggest complaints about distutils is that it doesn't do
> this, a limitation made worse by the fact that distutils allows you to
> specify an alternate data file directory, but your scripts have no way
> to know what that alternate directory is installed.  Which really
> limits the usefulness of that functionality.
>
> The most common way I've seen people work around this issue is to
> throw their data files into the package directories.  Yuck.

Huh. I always found that to be a more elegant solution than hardcoding the data 
location into the program at install-time.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python at mrabarnett.plus.com  Wed Jul  1 12:18:24 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 01 Jul 2009 17:18:24 +0100
Subject: Basic question from pure beginner
In-Reply-To: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
Message-ID: <4A4B8C50.4010202@mrabarnett.plus.com>

sato.photo at gmail.com wrote:
> I have been going through some Python Programming exercises while
> following the MIT OpenCourseWare Intro to CS syllabus and am having
> some trouble with the first "If" exercise listed on this page:
> 
> http://en.wikibooks.org/wiki/Python_Programming/Conditional_Statements#If_Exercises
> 
> I have been able to make the module quit after entering a password
> three times, but can't get it to quit right away after the correct one
> is entered.  I know this is really basic, please forgive me.  I have
> no programming experience and have just started going through these
> tutorials.
> 
> My code is here:
> 
> http://python.pastebin.com/m6036b52e
> 
raw_input() returns a string, so you don't need "guess = str(guess)".

The 'if' line should end with a colon.

Incrementing the count should probably be after the 'if' statement.

You can leave a loop prematurely with the 'break' statement.


From mail at timgolden.me.uk  Wed Jul  1 12:20:38 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 01 Jul 2009 17:20:38 +0100
Subject: No trees in the stdlib?
In-Reply-To: <h2f7ba$njc$5@lust.ihug.co.nz>
References: <mailman.2139.1245994218.8015.python-list@python.org>	<h21mgt$oav$1@panix3.panix.com>	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <4A4B8CD6.6050606@timgolden.me.uk>

Lawrence D'Oliveiro wrote:
> Want sorted order?
> 
>     sorted(tuple(the_set))

Not sure why you want the tuple () there, but
you probably knew that...

TJG


From python at mrabarnett.plus.com  Wed Jul  1 12:21:54 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 01 Jul 2009 17:21:54 +0100
Subject: No trees in the stdlib?
In-Reply-To: <h2f7ba$njc$5@lust.ihug.co.nz>
References: <mailman.2139.1245994218.8015.python-list@python.org>	<h21mgt$oav$1@panix3.panix.com>	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <4A4B8D22.3060308@mrabarnett.plus.com>

Lawrence D'Oliveiro wrote:
> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o 
> Valverde wrote:
> 
>> Simple example usage case: Insert string into data structure in sorted
>> order if it doesn't exist, else retrieve it.
> 
>     the_set = set( ... )
> 
>     if str in the_set :
>         ... "retrieval" case ...
>     else :
>         the_set.add(str)
>     #end if
> 
> Want sorted order?
> 
>     sorted(tuple(the_set))
> 
> What could be simpler?
> 
Why not just "sorted(the_set)"?


From charles at declareSub.com  Wed Jul  1 12:26:41 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Wed, 1 Jul 2009 12:26:41 -0400
Subject: Basic question from pure beginner
In-Reply-To: <49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
Message-ID: <1A63D369-87EF-4429-8C05-C1579C9BE71C@declareSub.com>

Let me offer a bit of editing.

First, using the condition count != 3 is perhaps risky.  A mistake or  
a change in logic in the loop body might result in an infinite loop.   
So instead I suggest

while count < 3...

Second, I'd suggest storing the value 3 in a variable with a name that  
describes it.

MaxAttempts = 3
while count < MaxAttempts

This suggests that you change the name 'count' to 'attemptcount'.

The variable 'guess' is used only inside the loop, so I suggest  
removing the assignment outside the loop.

Finally, I'd remove correct_password_given from the loop test, and  
replace it with a break statement when the correct password is entered.

password = "qwerty"
correct_password_given = False
attemptcount = 0
MaxAttempts = 3
while attemptcount < MaxAttempts:
   guess = raw_input("Enter your password: ")
   guess = str(guess)
   if guess != password:
       print "Access Denied"
       attemptcount = attemptcount + 1
   else:
       print "Password Confirmed"
       correct_password_given = True
       break


Charles Yeomans

On Jul 1, 2009, at 3:58 AM, sato.photo at gmail.com wrote:

> Thank you for all of the help.  With your assistance and help from the
> Python Tutor mailing list I was able to come up with the following
> code:
>
> password = "qwerty"
> correct_password_given = False
> guess = "0"
> count = 0
> while count != 3 and not correct_password_given :
>   guess = raw_input("Enter your password: ")
>   guess = str(guess)
>   if guess != password:
>       print "Access Denied"
>       count = count + 1
>   else:
>       print "Password Confirmed"
>       correct_password_given = True
>
>
> If I understand it correctly, the function will continue to loop until
> either the count == 3 or until correct_password_give = True,
> satisfying the two conditions of the assignment, which were to lock a
> user out after three failed password attempts and to print "Access
> Granted" and end the module if the correct password is given.  Am I
> understanding this correctly?
>
> Thanks!
>
> On Jul 1, 12:06 am, alex23 <wuwe... at gmail.com> wrote:
>> On Jul 1, 3:38 pm, "sato.ph... at gmail.com" <sato.ph... at gmail.com>
>> wrote:
>>
>>> I have been able to make the module quit after entering a password
>>> three times, but can't get it to quit right away after the correct  
>>> one
>>> is entered.
>>
>> Not with the code you pasted, you haven't. There's a missing colon on
>> line 7 & line 9 isn't indented properly. It's always best if we're
>> referring to the same source when trying to help with a problem.
>>
>> The problem you're having, though, has to do with the while loop and
>> the fact that it's only checking one condition: has the 'count'
>> counter been incremented to 3. What you need to do is _also_ check  
>> for
>> the success condition:
>>
>> is_confirmed = False
>> while count != 3 or is_confirmed:
>>   guess = raw_input("Enter your password: ")
>>   guess = str(guess)
>>   if guess != password:
>>     print "Access Denied"
>>     count = count + 1
>>   else:
>>     print "Password Confirmed"
>>     is_confirmed = True
>>
>> This also provides you with a nice boolean that shows whether or not
>> the password was confirmed, which may be useful for latter code.
>>
>> However, whenever you want to loop a set number of times, it's  
>> usually
>> better to use a 'for' loop instead:
>>
>> PASSWORD = 'qwerty'
>> MAXRETRY = 3
>> for attempt in xrange(MAXRETRY):
>>   guess = str(raw_input('Enter your password: '))
>>   is_complete = guess == PASSWORD
>>   if is_complete:
>>     print 'Password confirmed'
>>     break # this exits the for loop
>>   else:
>>     print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
>>
>> This saves you from the burden of creating, incrementing & testing
>> your own counter.
>>
>> If there's anything here that isn't clear, please don't hesitate to
>> ask.
>
> -- 
>



From bdesth.quelquechose at free.quelquepart.fr  Wed Jul  1 12:39:18 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 18:39:18 +0200
Subject: Getting input the scanf way
In-Reply-To: <mailman.2438.1246467374.8015.python-list@python.org>
References: <mailman.2438.1246467374.8015.python-list@python.org>
Message-ID: <4a4bacd3$0$296$426a74cc@news.free.fr>

Mr.SpOOn a ?crit :
> Hi,
> I need to do some kind of interactive command line program.
> 
> I mean: I run the program, it asks me for input, I type something and
> then I get the output or other questions.
> I'm not sure what is the right way to achieve this.

Simplest : use raw_input()
Friendlier (at least on *n*x platforms) : use readline.

HTH


From bdesth.quelquechose at free.quelquepart.fr  Wed Jul  1 12:43:44 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 18:43:44 +0200
Subject: Basic question from pure beginner
In-Reply-To: <mailman.2434.1246465610.8015.python-list@python.org>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
	<mailman.2434.1246465610.8015.python-list@python.org>
Message-ID: <4a4badde$0$10226$426a74cc@news.free.fr>

Charles Yeomans a ?crit :

<ot>Please don't top-post (not corrected)</ot>

> Let me offer a bit of editing.
> 
> First, using the condition count != 3 is perhaps risky.  A mistake or a 
> change in logic in the loop body might result in an infinite loop.  So 
> instead I suggest
> 
> while count < 3...
> 
> Second, I'd suggest storing the value 3 in a variable with a name that 
> describes it.

Pretty sensible suggestion, but then:

> MaxAttempts = 3

follow conventions instead :

MAX_ATTEMPS = 3


(snip)

> Finally, I'd remove correct_password_given from the loop test, and 
> replace it with a break statement when the correct password is entered.

Then using a while loop and manually incrementing a counter is a waste 
of time - using a for loop would be simplier and less error-prone.




From bdesth.quelquechose at free.quelquepart.fr  Wed Jul  1 12:45:26 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 18:45:26 +0200
Subject: Basic question from pure beginner
In-Reply-To: <npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
	<mailman.2434.1246465610.8015.python-list@python.org>
	<npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>
Message-ID: <4a4bae44$0$10226$426a74cc@news.free.fr>

Scott David Daniels a ?crit :
(snip)

> And even simpler:
>     PASSWORD = "qwerty"
>     MAXRETRY = 3
>     for attempt in range(MAXRETRY):
>         if raw_input('Enter your password: ') == PASSWORD:
>             print 'Password confirmed'
>             break # this exits the for loop
>         print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
>     else:
>         # The else for a for statement is not executed for breaks,
>         # So indicates the end of testing without a match
>         raise SystemExit # Or whatever you'd rather do.

Which is probably the most pythonic implementation.


From cmpython at gmail.com  Wed Jul  1 13:24:27 2009
From: cmpython at gmail.com (Che M)
Date: Wed, 1 Jul 2009 10:24:27 -0700 (PDT)
Subject: Ubigraph vs Matplotlib (dynamic plotting, event handling)
References: <300620092320590209%shaibani@ymail.com>
Message-ID: <307b4075-ec5b-4d06-a638-c62f38307e7e@q11g2000yqi.googlegroups.com>

On Jun 30, 6:20?pm, Ala <shaib... at ymail.com> wrote:
> Hello everyone,
>
> I intend to use python for some network graph plotting, with event
> handling (clicking on network nodes, zooming in/out etc..) and so far I
> have come across two good candidates which are Matplotlib and Ubigraph.
>
> Did anyone have any experience with either of them for dynamic plotting
> (a slider bar on a Qt interface causing the graph to be replotted for
> each value for example), as well as event handling? (it seems on first
> notice that Ubigraph will have an upperhand on that), as well as event
> handling such as mouse clicks? (on this one Matplotlib has good
> documentation showing it does achieve that while I find ubigraph's
> documentation lacking, but I'd preffere to have the opinion of those
> who have used them before).
>
> Thank you.

I have used Matplotlib for both uses.  It has a built-in toolbar that
allows for changing the plot (zoom, pan, etc), and has good support
for point picking (clicking on a datapoint to do send an event).  You
could probably connect the QT slider to the zoom function without much
trouble, and Matplotlib is embeddable in QT GUIs.


From andrew at acooke.org  Wed Jul  1 13:42:06 2009
From: andrew at acooke.org (andrew cooke)
Date: Wed, 1 Jul 2009 13:42:06 -0400 (CLT)
Subject: Suppressing Implicit Chained Exceptions (Python 3.0)
Message-ID: <59a8ef2bf270d290bc5ef5ee98ceb717.squirrel@acooke.dyndns.org>


I have some (library) code where an exception is caught and, since the
underlying cause is rather obscure, a different exception is raised that
more clearly explains the issue to the caller.

However, when printed via format_exc(), this new exception still has the
old exception attached via the mechanism described at
http://www.python.org/dev/peps/pep-3134/ (this is Python 3.0).

Is there any simple way to stop this?  It's rather annoying and
misleading, as it exposes a lot of internal detail that the caller does
not understand or want.  This is marked as an "open issue" in the PEP
described above.

Thanks,
Andrew





From __peter__ at web.de  Wed Jul  1 13:44:56 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 01 Jul 2009 19:44:56 +0200
Subject: logging module and binary strings
References: <mailman.2429.1246465077.8015.python-list@python.org>
Message-ID: <h2g7ah$ngv$00$1@news.t-online.com>

Frank Aune wrote:

>>>> import logging
>>>> logging.basicConfig(level=logging.DEBUG)
>>>> x='\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>>> x
> '\xfe\x9f\xce\xc3\xa1\x00\xff\x01'

>>>> logging.info(x)
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>     stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xfe in position 10:
> ordinal not in range(128)
>>>> logging.info(x, extra={'encoding':'utf-8'})
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>     stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'utf8' codec can't decode byte 0xfe in position 10:
> unexpected code byte

> Is there any way to log the above value of x "properly" using the python
> logging module? By properly I mean logging the value displayed when
> entering just x in the python shell and pressing enter.

How about logging.info(repr(x))?

Peter




From Scott.Daniels at Acm.Org  Wed Jul  1 13:47:47 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 01 Jul 2009 10:47:47 -0700
Subject: Basic question from pure beginner
In-Reply-To: <mailman.2434.1246465610.8015.python-list@python.org>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
	<mailman.2434.1246465610.8015.python-list@python.org>
Message-ID: <npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>

Charles Yeomans wrote:
> Let me offer a bit of editing....
> Finally, I'd remove correct_password_given from the loop test, and 
> replace it with a break statement when the correct password is entered.
> 
> password = "qwerty"
> correct_password_given = False
> attemptcount = 0
> MaxAttempts = 3
> while attemptcount < MaxAttempts:
>   guess = raw_input("Enter your password: ")
>   guess = str(guess)
>   if guess != password:
>       print "Access Denied"
>       attemptcount = attemptcount + 1
>   else:
>       print "Password Confirmed"
>       correct_password_given = True
>       break


And even simpler:
     PASSWORD = "qwerty"
     MAXRETRY = 3
     for attempt in range(MAXRETRY):
         if raw_input('Enter your password: ') == PASSWORD:
             print 'Password confirmed'
             break # this exits the for loop
         print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
     else:
         # The else for a for statement is not executed for breaks,
         # So indicates the end of testing without a match
         raise SystemExit # Or whatever you'd rather do.

--Scott David Daniels
Scott.Daniels at Acm.Org


From no.email at please.post  Wed Jul  1 13:56:55 2009
From: no.email at please.post (kj)
Date: Wed, 1 Jul 2009 17:56:55 +0000 (UTC)
Subject: Why re.match()?
Message-ID: <h2g817$mjo$1@reader1.panix.com>



For a recovering Perl-head like me it is difficult to understand
why Python's re module offers both match and search.  Why not just
use search with a beginning-of-string anchor?  I find it particularly
puzzling because I have this (possibly mistaken) idea that the
Python design philosophy tends towards minimalism, a sort of Occam's
razor, when it comes to language entities; i.e. having re.match
along with re.search seems to me like an "unnecessary multiplication
of entities".  What am I missing?

TIA!

kj


From timmyt at smarttypes.org  Wed Jul  1 13:58:33 2009
From: timmyt at smarttypes.org (timmyt)
Date: Wed, 1 Jul 2009 10:58:33 -0700 (PDT)
Subject: a little wsgi framework
Message-ID: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>

i'm interested in getting opinions on a small wsgi framework i
assembled from webob, sqlalchemy, genshi, and various code fragments i
found on the inter-tubes

here is the interesting glue - any comments / suggestions would be
much appreciated

------------------
the wsgi app
------------------
def application(environ, start_response):
    path = environ.get('PATH_INFO', '').lstrip('/')

    for regex, callback in urls:
        match = re.search(regex, path)

        if match:
            environ['myapp.url_args'] = match.groups()
            request = webob.Request(environ)

            try:
                return callback(request, start_response)
            except Exception, ex:
                start_response('500 Internal Server Error', [('Content-
Type', 'text/plain')])
                return [traceback.format_exc()]

    start_response('404 Not Found', [('Content-Type', 'text/plain')])
    return ["Couldn't find the URL specified."]


----------------------------------
the controller decorator
----------------------------------
def web_decorator(filename, method='html'):

    def decorator(target):

        def wrapper(request, start_response):

            #genshi TemplateLoader
            template = loader.load(filename)

            global config

            try:
                return_dict = target(request, start_response)
                return_string = template.generate(**return_dict).render
(method)
                config['database.Session'].commit()
            except:
                config['database.Session'].rollback()
                raise
            finally:
                config['database.Session'].remove()

            #TODO: alter 'Content-Type' per method being passed
            start_response('200 OK', [('Content-Type', 'text/html')])
            return [return_string]

        return wrapper

    return decorator


From lists at cheimes.de  Wed Jul  1 14:01:55 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 01 Jul 2009 20:01:55 +0200
Subject: A question about fill_free_list(void) function
In-Reply-To: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
Message-ID: <h2g8aj$tnb$1@ger.gmane.org>

Pedram schrieb:
> Hello community,
> I'm reading the CPython interpreter source code,
> first, if you have something that I should know for better reading
> this source code, I would much appreciate that :)
> second, in intobject.c file, I read the following code in
> fill_free_list function that I couldn't understand:
> <code>while (--q > p)
>     Py_TYPE(q) = (struct _typeobject *)(q-1);
> Py_TYPE(q) = NULL;
> </code>
> What does it mean?

The code is abusing the ob_type member to store a single linked, NULL
terminated list of free integer objects. It's a tricky optimization you
don't have to understand in order to understand the rest of the code.

And no, the code in ctypes.h is totally unrelated to the free list in
intobject.c.

Christian



From robert.kern at gmail.com  Wed Jul  1 14:33:53 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 01 Jul 2009 13:33:53 -0500
Subject: deleting certain entries in numpy array
In-Reply-To: <4a4b7763$1@news.fhg.de>
References: <4a4b7763$1@news.fhg.de>
Message-ID: <h2ga6h$3dt$1@ger.gmane.org>

On 2009-07-01 09:51, Sebastian Schabe wrote:
> Hello everybody,
>
> I'm new to python and numpy and have a little/special problem:

You will want to ask numpy questions on the numpy mailing list.

   http://www.scipy.org/Mailing_Lists

> I have an numpy array which is in fact a gray scale image mask, e.g.:
>
> mask =
> array([[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 255, 255, 255, 0, 0, 255, 0],
> [ 0, 0, 255, 255, 255, 0, 0, 255, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0]], dtype=uint8)
>
> and I have another array of (y, x) positions in that mask (first two
> values of each row):
>
> pos =
> array([[ 3., 2., 0., 0.],
> [ 3., 4., 0., 0.],
> [ 5., 2., 0., 0.],
> [ 5., 4., 0., 0.],
> [ 6., 2., 0., 0.],
> [ 6., 7., 0., 0.],
> [ 0., 0., 0., 0.],
> [ 8., 8., 0., 0.]])
>
> and now I only want to keep all lines from 2nd array pos with those
> indices that are nonzero in the mask, i.e. line 3-6 (pos[2]-pos[5]).
>
> F.e. line 4 in pos has the values (5, 4) and mask[5][4] is nonzero, so I
> want to keep it. While line 2 (pos[1]) has the values (4, 6) and
> mask[4][6] is zero, so shall be discarded.
>
> I want to avoid a for loop (if possible!!!) cause I think (but don't
> know) numpy array are handled in another way. I think numpy.delete is
> the right function for discarding the values, but I don't know how to
> build the indices.

First, convert the pos array to integers, and just the columns with indices in them:

   ipos = pos[:,:2].astype(int)

Now check the values in the mask corresponding to these positions:

   mask_values = mask[ipos[:,0], ipos[:,1]]

Now extract the rows from the original pos array where mask_values is nonzero:

   result = pos[mask_values != 0]

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From backup95 at netcabo.pt  Wed Jul  1 14:45:26 2009
From: backup95 at netcabo.pt (=?UTF-8?B?Sm/Do28gVmFsdmVyZGU=?=)
Date: Wed, 01 Jul 2009 19:45:26 +0100
Subject: No trees in the stdlib?
In-Reply-To: <h2f7ba$njc$5@lust.ihug.co.nz>
References: <mailman.2139.1245994218.8015.python-list@python.org>	<h21mgt$oav$1@panix3.panix.com>	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <4A4BAEC6.1060109@netcabo.pt>

Lawrence D'Oliveiro wrote:
> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o 
> Valverde wrote:
>
>   
>> Simple example usage case: Insert string into data structure in sorted
>> order if it doesn't exist, else retrieve it.
>>     
>
>     the_set = set( ... )
>
>     if str in the_set :
>         ... "retrieval" case ...
>     else :
>         the_set.add(str)
>     #end if
>
> Want sorted order?
>
>     sorted(tuple(the_set))
>
> What could be simpler?
>
>   

Try putting that inside a loop with thousands of iterations and you'll 
see what the problem is.


From duncan.booth at invalid.invalid  Wed Jul  1 14:52:34 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 1 Jul 2009 18:52:34 GMT
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
Message-ID: <Xns9C3BCA27ABC36duncanbooth@127.0.0.1>

kj <no.email at please.post> wrote:

> 
> 
> For a recovering Perl-head like me it is difficult to understand
> why Python's re module offers both match and search.  Why not just
> use search with a beginning-of-string anchor?  I find it particularly
> puzzling because I have this (possibly mistaken) idea that the
> Python design philosophy tends towards minimalism, a sort of Occam's
> razor, when it comes to language entities; i.e. having re.match
> along with re.search seems to me like an "unnecessary multiplication
> of entities".  What am I missing?
> 
RTFM?

http://docs.python.org/library/re.html#matching-vs-searching says:

> Note that match may differ from search even when using a regular
> expression beginning with '^': '^' matches only at the start of the
> string, or in MULTILINE mode also immediately following a newline. The
> ?match? operation succeeds only if the pattern matches at the start of
> the string regardless of mode, or at the starting position given by
> the optional pos argument regardless of whether a newline precedes
> it. 

So, for example:

>>> re.compile("c").match("abcdef", 2)
<_sre.SRE_Match object at 0x0000000002C09B90>
>>> re.compile("^c").search("abcdef", 2)
>>>

The ^ anchors you to the start of the string (or start of line in multiline 
mode) even if you specify a non-zero position. The match method just tells 
you if the pattern matches at the specified starting position regardless of 
whether it is the start of the string.



From damienlmoore at gmail.com  Wed Jul  1 15:30:51 2009
From: damienlmoore at gmail.com (spillz)
Date: Wed, 1 Jul 2009 12:30:51 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org>
Message-ID: <e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com>

On Jun 29, 3:15?pm, Pascal Chambon <chambon.pas... at gmail.com> wrote:
> Hello everyone
>
> I've had real issues with subprocesses recently : from a python script,
> on windows, I wanted to "give control" to a command line utility, i.e
> forward user in put to it and display its output on console. It seems
> simple, but I ran into walls :


If you are willing to have a wxPython dependency, wx.Execute handles
non-blocking i/o with processes on all supported platforms

more discussion of python's blocking i/o issues here:
http://groups.google.com/group/comp.lang.python/browse_thread/thread/a037349e18f99630/60886b8beb55cfbc?q=#60886b8beb55cfbc


From melissa at corsairsolutions.com  Wed Jul  1 15:57:35 2009
From: melissa at corsairsolutions.com (Melissa Powers)
Date: Wed, 1 Jul 2009 15:57:35 -0400
Subject: Python 2.5 incompatible with Fedora Core 6 - packaging problems
	again
Message-ID: <51BDF10DBC00564DBBBE62B537CF53922B9ADD@csi-svr1.csi.local>

Hi,

 

This may be a stretch but I came across this blog while searching for a
SW Packaging Engineer.  Do you know anyone in the Boston, MA area who
may be interested in this position?  The company is a start up with a
lot of funding and this is an opportunity to define the environment and
grow with a promising company.  Please4= forward to anyone you may know
of...

 

SW Packaging Engineer

*         Python developer

*         Red Hat Applications expert (Fedora 10) 

*         They want a real Red Hat Linux expert

*         Custom Build Distribution 

*         Custom RPM's 

*         Some Linux Server administration duties 

*         Virtualization experience a big plus

 

 

Melissa Frechette Powers

Account Manager

Corsair Solutions, Inc.

2 New Pasture Rd Unit 1

Newburyport, MA 01950

978-465-0085 x 206 Phone

978-465-0068 Fax

 

http://www.corsairsolutions.com <http://www.corsairsolutions.com> 

Please visit our NEW website: www.corsairsolutions.com
<http://www.corsairsolutions.com> 

 

The documents included with this electronic mail transmission contain
information from the staffing firm of Corsair Solutions, Inc which is
confidential and/or privileged. This information is intended to be for
the use of the addressee only. Note that any disclosure, printing,
photocopying, distribution or use of the contents of this e-mailed
information by persons other than the addressee or an agent of the
addressee, is unauthorized and prohibited. If you have received this
electronic mail in error, please notify us via electronic mail reply to
the sender or by telephone (collect 877-626-7724) immediately.

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/6e5070b4/attachment.html>

From stef.mientki at gmail.com  Wed Jul  1 16:08:13 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Wed, 01 Jul 2009 22:08:13 +0200
Subject: Adding an object to the global namespace through " f_globals"  is
	that allowed ?
Message-ID: <4A4BC22D.70502@gmail.com>

hello,

I need to add an object's name to the global namespace.
The reason for this is to create an environment,
where you can add some kind of math environment,
where no need for Python knowledge is needed.

The next statement works,
but I'm not sure if it will have any dramatical side effects,
other than overruling a possible object with the name A

def some_function ( ...) :
      A = object ( ...)
      sys._getframe(1).f_globals [ Name ] = A


thanks,
Stef Mientki


From ben+python at benfinney.id.au  Wed Jul  1 16:16:43 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 02 Jul 2009 06:16:43 +1000
Subject: deleting certain entries in numpy array
References: <4a4b7763$1@news.fhg.de>
Message-ID: <87fxdgtaz8.fsf@benfinney.id.au>

Sebastian Schabe <sebastian.schabe at gmx.de> writes:

> I want to avoid a for loop (if possible!!!) cause I think (but don't
> know) numpy array are handled in another way.

Yes, Numpy arrays can be indexed logically by a boolean array.

> I think numpy.delete is the right function for discarding the values,
> but I don't know how to build the indices.

You don't need to discard the values. You can get a new array which is a
filtered version of an existing array, by using an array of bool values
as the index to the old array::

    >>> import numpy
    >>> mask = numpy.array([
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0, 255, 255, 255,   0,   0, 255,   0],
    ...     [  0,   0, 255, 255, 255,   0,   0, 255,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     ], dtype=numpy.uint8)
    >>> mask > 0
    array([[False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False,  True,  True,  True, False, False,  True, False],
           [False, False,  True,  True,  True, False, False,  True, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False]],
           dtype=bool)
    >>> mask[mask > 0]
    array([255, 255, 255, 255, 255, 255, 255, 255], dtype=uint8)

However, your case is somewhat more tricky: you need to construct the
boolean array based on coordinates from a separate array. That doesn't
require a for loop statement, but AFAICT it does require manually
generating the array of bools. I've done it with a list comprehension::

    >>> pos = numpy.array([
    ...     [  3.,   2.,   0.,   0.],
    ...     [  3.,   4.,   0.,   0.],
    ...     [  5.,   2.,   0.,   0.],
    ...     [  5.,   4.,   0.,   0.],
    ...     [  6.,   2.,   0.,   0.],
    ...     [  6.,   7.,   0.,   0.],
    ...     [  0.,   0.,   0.,   0.],
    ...     [  8.,   8.,   0.,   0.],
    ...     ])
    >>> pos[numpy.array(
    ...     [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]])]
    array([[ 5.,  2.,  0.,  0.],
           [ 5.,  4.,  0.,  0.],
           [ 6.,  2.,  0.,  0.],
           [ 6.,  7.,  0.,  0.]])

Here it is again, showing my working steps::

    >>> pos[:, 0:2]
    array([[ 3.,  2.],
           [ 3.,  4.],
           [ 5.,  2.],
           [ 5.,  4.],
           [ 6.,  2.],
           [ 6.,  7.],
           [ 0.,  0.],
           [ 8.,  8.]])
    >>> [(int(x), int(y)) for (x, y) in pos[:, 0:2]]
    [(3, 2), (3, 4), (5, 2), (5, 4), (6, 2), (6, 7), (0, 0), (8, 8)]
    >>> [mask[int(x), int(y)] for (x, y) in pos[:, 0:2]]
    [0, 0, 255, 255, 255, 255, 0, 0]
    >>> [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]]
    [False, False, True, True, True, True, False, False]
    >>> numpy.array(
    ...     [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]])
    array([False, False,  True,  True,  True,  True, False, False],
    dtype=bool)
    >>> pos[numpy.array(
    ...     [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]])]
    array([[ 5.,  2.,  0.,  0.],
           [ 5.,  4.,  0.,  0.],
           [ 6.,  2.,  0.,  0.],
           [ 6.,  7.,  0.,  0.]])

-- 
 \                            ?Holy knit one purl two, Batman!? ?Robin |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From Digvijoy.C at gmail.com  Wed Jul  1 16:20:03 2009
From: Digvijoy.C at gmail.com (digz)
Date: Wed, 1 Jul 2009 13:20:03 -0700 (PDT)
Subject: problems displaying results in ibm_db
Message-ID: <c59882af-be7e-4212-8020-8a3984e5fa5f@k8g2000yqn.googlegroups.com>

This simple db connectivity and select test program works in the
interactive mode

>>> import ibm_db
>>> conn = ibm_db.connect( 'DATABASE', 'user', 'passwd')
>>> result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST 1 ROWS ONLY')
>>> row = ibm_db.fetch_tuple( result )
>>> for r in row:
...    print r
...
13
ABC
4
2009-05-11

The same executed from a script using python testdb.py does not yield
anything , What am I doing wrong ?

import ibm_db
conn = ibm_db.connect( 'DATABASE', 'user', 'pwd')
result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST
1 ROWS ONLY')
row = ibm_db.fetch_tuple( result )
for r in row:
      print r

==
>python testdb.py
database value after unicode conversion is : N
database value sent to CLI is : N
>
==


From psimon at sonic.net  Wed Jul  1 17:16:18 2009
From: psimon at sonic.net (Paul Simon)
Date: Wed, 1 Jul 2009 14:16:18 -0700
Subject: problem installing python 2.6.2 from tarball
Message-ID: <4a4bd226$0$95520$742ec2ed@news.sonic.net>

I have just finished going through the usual ./configure, make, etc. and now 
have a load of stuff in my home directory that I think doesn't belong there. 
Apparently I did the installation from my home directory (linux) and have a 
directory  in my home directory "Python2.6.2" with subdirectories like 
"build", "Demo", "Doc", "Include", "Lib", etc.  There are many files under 
/usr/bin/local/  which appear to be duplicates.

This looks like a mess to me and would like some help to sort this out.

Paul Simon 




From Mariosky at gmail.com  Wed Jul  1 17:34:51 2009
From: Mariosky at gmail.com (Mario Garcia)
Date: Wed, 1 Jul 2009 14:34:51 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method returns 
	items in order
Message-ID: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>

Im trying to use sets for doing statistics from a data set.
I want to select, 70% random records from a List. I thougth set where
a good idea so I
tested this way:

c = set(range(1000))
for d in range(1000):
     print c.pop()

I was hoping to see a print out of random selected numbers from 1 to
1000
but I got an ordered count from 1 to 1000.
I also tried using a dictionary, with keys from 1 to 10, and also got
the keys in order.

Im using:
 Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug  4 2008, 13:45:20)
 [GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin

Examples in the documentation seem to work. But I cant make it.
Can some one, give me a hint on whats going on?




From lance.ellinghaus at hp.com  Wed Jul  1 18:02:49 2009
From: lance.ellinghaus at hp.com (ELLINGHAUS, LANCE)
Date: Wed, 1 Jul 2009 22:02:49 +0000
Subject: Using Python to set desktop background image under Windows XP
In-Reply-To: <h2f7jt$j33$1@south.jnrs.ja.net>
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
Message-ID: <197A4D1DF629F64A9260E3B454A218D13403C48D2E@GVW1158EXB.americas.hpqcorp.net>

Does anyone have any code that would allow setting the desktop background image under Windows XP?

Thank you,
lance


Lance Ellinghaus
mailto:lance.ellinghaus at hp.com


From skip at pobox.com  Wed Jul  1 18:07:16 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 1 Jul 2009 17:07:16 -0500
Subject: Timeout when connecting to sybase DBS
In-Reply-To: <794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
Message-ID: <19019.56852.751152.510037@montanaro.dyndns.org>

    Gil> Are you saying, that when you trying to connect to a sybase DBS
    Gil> server and the DBS or the server is down, you get an error after a
    Gil> few seconds and not after a few minutes?

Yes, though thankfully our server tends to almost always be up.

    Gil> Which python version are you using?

We're still running 2.4.5 at work and have a slightly hacked very old
version of the python-sybase package (0.36).

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    when i wake up with a heart rate below 40, i head right for the espresso
    machine. -- chaos @ forums.usms.org


From rhodri at wildebst.demon.co.uk  Wed Jul  1 18:08:33 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 01 Jul 2009 23:08:33 +0100
Subject: Python/Pygame question
In-Reply-To: <cab5c962-5833-4d4f-89dc-c1475c8076bf@j32g2000yqh.googlegroups.com>
References: <cab5c962-5833-4d4f-89dc-c1475c8076bf@j32g2000yqh.googlegroups.com>
Message-ID: <op.uwes4jnja8ncjz@gnudebst>

On Tue, 30 Jun 2009 19:15:24 +0100, Crip <cripplemeal at gmail.com> wrote:

> I have been experimenting with pygame. I would like to know how to go
> about placing an image of my creation as the background of the
> generated window. To where should I save the image, and what should it
> be saved as?

Wherever will be most useful to you (the same directory as where you
are developing your game is often good).  You can use most of the common
formats, so pick whatever's most appropriate for your image.

The documentation is at http://www.pygame.org/docs/ref/image.html
In particular, you use pygame.image.load() to load your file into a
surface, then blit it into your display.  Some resizing may be
necessary!


-- 
Rhodri James *-* Wildebeest Herder to the Masses


From skip at pobox.com  Wed Jul  1 18:08:57 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 1 Jul 2009 17:08:57 -0500
Subject: Timeout when connecting to sybase DBS
In-Reply-To: <5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com>
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
	<5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com>
Message-ID: <19019.56953.762133.210100@montanaro.dyndns.org>

    Gil> There's no such group as python-sybase :-(

http://sourceforge.net/mailarchive/forum.php?forum_name=python-sybase-misc

S


From clp2 at rebertia.com  Wed Jul  1 18:11:45 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 1 Jul 2009 15:11:45 -0700
Subject: Noob
In-Reply-To: <d152d3690906301102j63d1bd74uc90cd0a56144d2fe@mail.gmail.com>
References: <d152d3690906301102j63d1bd74uc90cd0a56144d2fe@mail.gmail.com>
Message-ID: <50697b2c0907011511r6aac78d9m3f190c19b79ed832@mail.gmail.com>

On Tue, Jun 30, 2009 at 11:02 AM, kaffeen<kaffeen at gmail.com> wrote:
> Hello all, just joined this list and am just beginning to learn Python.
> Thanks to everyone for making this a great place to learn and their
> contributions.
>
> As mentioned, I'm new to Python (but have experience with other programming
> languages/scripting). I have a couple of questions...
<snip>
> 2) What are the differences between IPython and IDLE, is one better than the
> other, why?

IDLE is a GUI interactive interpreter and IDE that uses the Tk GUI toolkit.
IPython is a command-line interactive interpreter with tab-completion,
advanced command history functions, and other handy extras.

I would say they have completely different purposes. IPython is a
souped-up version of the command-line Python REPL, but doesn't include
a text editor for writing a file of code. It is very good for
experimenting and exploring with though. IDLE is a quite servicable
free IDE.

Cheers,
Chris
-- 
http://blog.rebertia.com


From pavlovevidence at gmail.com  Wed Jul  1 18:28:10 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 15:28:10 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>

On Jul 1, 2:34?pm, Mario Garcia <Mario... at gmail.com> wrote:
> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I
> tested this way:
>
> c = set(range(1000))
> for d in range(1000):
> ? ? ?print c.pop()
>
> I was hoping to see a print out of random selected numbers from 1 to
> 1000
> but I got an ordered count from 1 to 1000.
> I also tried using a dictionary, with keys from 1 to 10, and also got
> the keys in order.
>
> Im using:
> ?Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug ?4 2008, 13:45:20)
> ?[GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin
>
> Examples in the documentation seem to work. But I cant make it.
> Can some one, give me a hint on whats going on?

The keys in a dict or set are not in random order, but (more or less)
they are in hash key order modulo the size of the hash.  This neglects
the effect of hash collisions.  The hash code of an integer happens to
the integer itself, so oftentimes a dict or set storing a sequence of
integers will end up with keys in order, although it's not guaranteed
to be so.

Point it, it's unsafe to rely on *any* ordering behavior in a dict or
set, even relatively random order.

Instead, call random.shuffle() on the list, and iterate through that
to get the elements in random order.


Carl Banks


From mensanator at aol.com  Wed Jul  1 18:29:19 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 1 Jul 2009 15:29:19 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <51a36108-d3dc-4a03-9a85-84a5da9b541a@l31g2000yqb.googlegroups.com>

On Jul 1, 4:34?pm, Mario Garcia <Mario... at gmail.com> wrote:
> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I
> tested this way:
>
> c = set(range(1000))
> for d in range(1000):
> ? ? ?print c.pop()
>
> I was hoping to see a print out of random selected numbers from 1 to
> 1000
> but I got an ordered count from 1 to 1000.
> I also tried using a dictionary, with keys from 1 to 10, and also got
> the keys in order.
>
> Im using:
> ?Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug ?4 2008, 13:45:20)
> ?[GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin
>
> Examples in the documentation seem to work. But I cant make it.
> Can some one, give me a hint on whats going on?

Sets don't help. Try this:

>>> import random

>>> c = range(100)
>>> c
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

>>> random.shuffle(c)
>>> c
[78, 62, 38, 54, 12, 48, 24, 20, 8, 14, 1, 69, 49, 92, 41, 64, 17, 35,
88, 40, 73, 45, 5, 84, 96, 90, 98, 57, 51, 75, 99, 13, 29, 4, 97, 77,
74, 56, 91, 95, 59, 79, 89, 19, 9, 42, 31, 85, 86, 23, 27, 50, 6, 21,
15, 80, 3, 30, 87, 82, 16, 63, 2, 55, 37, 33, 10, 61, 93, 72, 60, 67,
44, 65, 11, 70, 52, 58, 47, 18, 36, 66, 94, 28, 22, 68, 32, 76, 53,
25, 83, 34, 26, 71, 39, 43, 7, 46, 0, 81]

>>> for d in c:
	print c.pop(),

81 0 46 7 43 39 71 26 34 83 25 53 76 32 68 22 28 94 66 36 18 47 58 52
70 11 65 44 67 60 72 93 61 10 33 37 55 2 63 16 82 87 30 3 80 15 21 6
50 27

Notice that the numbers are coming out in the exact reverse order
of the list, because you used .pop() without an index number.
But it's ok in _THIS_ example, because the list was randomly
shuffled before popping.


From pavlovevidence at gmail.com  Wed Jul  1 18:33:01 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 15:33:01 -0700 (PDT)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
Message-ID: <86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>

On Jul 1, 10:56?am, kj <no.em... at please.post> wrote:
> For a recovering Perl-head like me it is difficult to understand
> why Python's re module offers both match and search. ?Why not just
> use search with a beginning-of-string anchor? ?I find it particularly
> puzzling because I have this (possibly mistaken) idea that the
> Python design philosophy tends towards minimalism, a sort of Occam's
> razor, when it comes to language entities; i.e. having re.match
> along with re.search seems to me like an "unnecessary multiplication
> of entities". ?What am I missing?

It always seemed redundant to me also (notwithstanding Duncan Booth's
explanation of slight semantic differences).  However, I find myself
using re.match much more often than re.search, so perhaps in this case
a "second obvious way" is justified.


Carl Banks


From aahz at pythoncraft.com  Wed Jul  1 18:39:55 2009
From: aahz at pythoncraft.com (Aahz)
Date: 1 Jul 2009 15:39:55 -0700
Subject: Problem with uuid package when embedding a python interpreter
References: <7d5cfbf0-38d5-4505-a93a-f321d0da74b8@c36g2000yqn.googlegroups.com>
Message-ID: <h2gojr$e1u$1@panix3.panix.com>

In article <7d5cfbf0-38d5-4505-a93a-f321d0da74b8 at c36g2000yqn.googlegroups.com>,
=?ISO-8859-1?Q?J=E9r=F4me_Fuselier?=  <jerome.fuselier at gmail.com> wrote:
>
>I've tried to import a script in an embedded python intrepreter but
>this script fails when it imports the uuid module. I have a
>segmentation fault in Py_Finalize().

You may want to also ask on the capi-sig mailing list.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From mensanator at aol.com  Wed Jul  1 18:47:08 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 1 Jul 2009 15:47:08 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<51a36108-d3dc-4a03-9a85-84a5da9b541a@l31g2000yqb.googlegroups.com>
Message-ID: <6891d82f-9dc3-4f43-8490-c339edf85ad8@p23g2000vbl.googlegroups.com>

On Jul 1, 5:29?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 1, 4:34?pm, Mario Garcia <Mario... at gmail.com> wrote:
>
>
>
>
>
> > Im trying to use sets for doing statistics from a data set.
> > I want to select, 70% random records from a List. I thougth set where
> > a good idea so I
> > tested this way:
>
> > c = set(range(1000))
> > for d in range(1000):
> > ? ? ?print c.pop()
>
> > I was hoping to see a print out of random selected numbers from 1 to
> > 1000
> > but I got an ordered count from 1 to 1000.
> > I also tried using a dictionary, with keys from 1 to 10, and also got
> > the keys in order.
>
> > Im using:
> > ?Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug ?4 2008, 13:45:20)
> > ?[GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin
>
> > Examples in the documentation seem to work. But I cant make it.
> > Can some one, give me a hint on whats going on?
>
> Sets don't help. Try this:
>
> >>> import random
> >>> c = range(100)
> >>> c
>
> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
> 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
> 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
> 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
> 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
> 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]
>
> >>> random.shuffle(c)
> >>> c
>
> [78, 62, 38, 54, 12, 48, 24, 20, 8, 14, 1, 69, 49, 92, 41, 64, 17, 35,
> 88, 40, 73, 45, 5, 84, 96, 90, 98, 57, 51, 75, 99, 13, 29, 4, 97, 77,
> 74, 56, 91, 95, 59, 79, 89, 19, 9, 42, 31, 85, 86, 23, 27, 50, 6, 21,
> 15, 80, 3, 30, 87, 82, 16, 63, 2, 55, 37, 33, 10, 61, 93, 72, 60, 67,
> 44, 65, 11, 70, 52, 58, 47, 18, 36, 66, 94, 28, 22, 68, 32, 76, 53,
> 25, 83, 34, 26, 71, 39, 43, 7, 46, 0, 81]
>
> >>> for d in c:

Oops! You don't want to iterate through c while popping it.
Your original for statement is what to use.

>
> ? ? ? ? print c.pop(),
>
> 81 0 46 7 43 39 71 26 34 83 25 53 76 32 68 22 28 94 66 36 18 47 58 52
> 70 11 65 44 67 60 72 93 61 10 33 37 55 2 63 16 82 87 30 3 80 15 21 6
> 50 27
>
> Notice that the numbers are coming out in the exact reverse order
> of the list, because you used .pop() without an index number.
> But it's ok in _THIS_ example, because the list was randomly
> shuffled before popping.


From ben+python at benfinney.id.au  Wed Jul  1 19:01:10 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 02 Jul 2009 09:01:10 +1000
Subject: Trying to use sets for random selection,
	but the pop() method returns  items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <87bpo4t3d5.fsf@benfinney.id.au>

Mario Garcia <Mariosky at gmail.com> writes:

> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I
> tested this way:
> 
> c = set(range(1000))
> for d in range(1000):
>      print c.pop()
> 
> I was hoping to see a print out of random selected numbers from 1 to
> 1000

The ?set? and ?dict? types are unordered collections, but that doesn't
have any implication of randomness. Rather, it means that the order of
retrieval is not guaranteed to be predictable.

You can't even predict that it'll be a random order; you can't predict
(based on the Python code) *anything* about the order. Any appearance of
predictable ordering is an unreliable artefact of the implementation and
may change at any time, since the language explicitly disclaims any
specific ordering to the items.

For a random sequence, you want the ?random? module
<URL:http://docs.python.org/library/random>::

    >>> import random
    >>> for n in (random.randint(0, 999) for _ in range(10)):
    ...     print n
    ...
    381
    4
    471
    624
    70
    979
    110
    932
    105
    262 

-- 
 \        ?When in doubt tell the truth. It will confound your enemies |
  `\   and astound your friends.? ?Mark Twain, _Following the Equator_ |
_o__)                                                                  |
Ben Finney


From alex.lavoro.propio at gmail.com  Wed Jul  1 19:18:13 2009
From: alex.lavoro.propio at gmail.com (Alex)
Date: Wed, 1 Jul 2009 16:18:13 -0700 (PDT)
Subject: Open Source RSS Reader in Python?
Message-ID: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>

I am looking for an open source RSS reader (desktop, not online)
written in Python but in vain. I am not looking for a package but a
fully functional software.

Google: python "open source" (rss OR feeds) reader

Any clue ?


From tn.pablo at gmail.com  Wed Jul  1 19:26:36 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Wed, 1 Jul 2009 18:26:36 -0500
Subject: problem installing python 2.6.2 from tarball
In-Reply-To: <4a4bd226$0$95520$742ec2ed@news.sonic.net>
References: <4a4bd226$0$95520$742ec2ed@news.sonic.net>
Message-ID: <fdd00b510907011626u3bb9e652nc116843560d573ee@mail.gmail.com>

On Wed, Jul 1, 2009 at 16:16, Paul Simon<psimon at sonic.net> wrote:
> I have just finished going through the usual ./configure, make, etc. and now
> have a load of stuff in my home directory that I think doesn't belong there.
> Apparently I did the installation from my home directory (linux) and have a
> directory ?in my home directory "Python2.6.2" with subdirectories like
> "build", "Demo", "Doc", "Include", "Lib", etc. ?There are many files under
> /usr/bin/local/ ?which appear to be duplicates.
>
> This looks like a mess to me and would like some help to sort this out.
>
> Paul Simon

Sounds like you untarred directly into your home dir.  You're OK if
you delete those, they are the sources, although you should do so only
after uninstalling, just in case.
To unistall, follow this thread from the list from a while ago:
http://mail.python.org/pipermail/python-list/2004-December/296269.html
I have followed it and it worked.

Pablo Torres N.


From tn.pablo at gmail.com  Wed Jul  1 19:34:18 2009
From: tn.pablo at gmail.com (ptn)
Date: Wed, 1 Jul 2009 16:34:18 -0700 (PDT)
Subject: problems displaying results in ibm_db
References: <c59882af-be7e-4212-8020-8a3984e5fa5f@k8g2000yqn.googlegroups.com>
Message-ID: <052ecdf2-6253-4885-9f16-2f24062f1f07@g6g2000vbr.googlegroups.com>

On Jul 1, 3:20?pm, digz <Digvijo... at gmail.com> wrote:
> result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST
> 1 ROWS ONLY')

You have the same string split into two lines, which means that what
you actually have is this:

result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH
FIRST<NEWLINE CHARACTER HERE>
1 ROWS ONLY')

You need to escape that little '\n' with a backslash:

result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST\
1 ROWS ONLY')

Better yet, use implicit string concatenation:

result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST'
'1 ROWS ONLY')

Note that now you have two strings: 'SELECT * FROM TEST FETCH FIRST'
and  '1 ROWS ONLY'


Pablo Torres N.


From tn.pablo at gmail.com  Wed Jul  1 19:36:38 2009
From: tn.pablo at gmail.com (ptn)
Date: Wed, 1 Jul 2009 16:36:38 -0700 (PDT)
Subject: problem installing python 2.6.2 from tarball
References: <4a4bd226$0$95520$742ec2ed@news.sonic.net>
Message-ID: <9286d6b5-91bf-4a74-99ba-c7c90329d4aa@f33g2000vbm.googlegroups.com>

Sounds like you untarred directly into your home dir.  You're OK if
you delete those, they are the sources, although you should do so only
after uninstalling, just in case.

To unistall, follow this thread from the list from a while ago:
http://mail.python.org/pipermail/python-list/2004-December/296269.html

I have followed it and it worked.


From sajmikins at gmail.com  Wed Jul  1 19:39:31 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Wed, 1 Jul 2009 16:39:31 -0700 (PDT)
Subject: Open Source RSS Reader in Python?
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <cca5f130-2e9a-40d7-a6ad-c580f7daffb8@z28g2000vbl.googlegroups.com>

On Jul 1, 7:18?pm, Alex <alex.lavoro.pro... at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?

There's Canto: http://codezen.org/canto/


From python at mrabarnett.plus.com  Wed Jul  1 19:50:16 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 00:50:16 +0100
Subject: Why re.match()?
In-Reply-To: <86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>
Message-ID: <4A4BF638.5060500@mrabarnett.plus.com>

Carl Banks wrote:
> On Jul 1, 10:56 am, kj <no.em... at please.post> wrote:
>> For a recovering Perl-head like me it is difficult to understand
>> why Python's re module offers both match and search.  Why not just
>> use search with a beginning-of-string anchor?  I find it particularly
>> puzzling because I have this (possibly mistaken) idea that the
>> Python design philosophy tends towards minimalism, a sort of Occam's
>> razor, when it comes to language entities; i.e. having re.match
>> along with re.search seems to me like an "unnecessary multiplication
>> of entities".  What am I missing?
> 
> It always seemed redundant to me also (notwithstanding Duncan Booth's
> explanation of slight semantic differences).  However, I find myself
> using re.match much more often than re.search, so perhaps in this case
> a "second obvious way" is justified.
> 
re.match is anchored at a certain position, whereas re.search isn't. The
re module doesn't support Perl's \G anchor.


From robert.kern at gmail.com  Wed Jul  1 19:51:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 01 Jul 2009 18:51:31 -0500
Subject: logging module and binary strings
In-Reply-To: <200907011702.21450.Frank.Aune@broadpark.no>
References: <200907011702.21450.Frank.Aune@broadpark.no>
Message-ID: <h2gsq3$o8c$1@ger.gmane.org>

On 2009-07-01 10:02, Frank Aune wrote:
> Hello,
>
> ---- snip ----
>>>> import logging
>>>> logging.basicConfig(level=logging.DEBUG)
>>>> x='\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>>> x
> '\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>>> print x
> ?????
>>>> logging.info(x)
> Traceback (most recent call last):
>    File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>      stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xfe in position 10:
> ordinal not in range(128)
>>>> logging.info(x, extra={'encoding':'utf-8'})
> Traceback (most recent call last):
>    File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>      stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'utf8' codec can't decode byte 0xfe in position 10:
> unexpected code byte
>
> ---- snip ----
>
> Is there any way to log the above value of x "properly" using the python
> logging module? By properly I mean logging the value displayed when entering
> just x in the python shell and pressing enter.

logging.info(repr(x))

Or, to be more descriptive in your logging message:

logging.info("Got a binary value: %r", x)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From benjamin at python.org  Wed Jul  1 19:55:23 2009
From: benjamin at python.org (Benjamin Peterson)
Date: Wed, 1 Jul 2009 23:55:23 +0000 (UTC)
Subject: getting rid of  =?utf-8?b?4oCU?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
Message-ID: <loom.20090701T235446-25@post.gmane.org>

someone <petshmidt <at> googlemail.com> writes:

> 
> Hello,
> 
> how can I replace '?' sign from string? Or do split at that character?
> Getting unicode error if I try to do it:
> 
> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> 1: ordinal not in range(128)


Please paste your code. I suspect that you are mixing unicode and normal strings.






From python at mrabarnett.plus.com  Wed Jul  1 19:56:22 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 00:56:22 +0100
Subject: getting rid of  =?windows-1252?Q?=97?=
In-Reply-To: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
Message-ID: <4A4BF7A6.9010500@mrabarnett.plus.com>

someone wrote:
> Hello,
> 
> how can I replace '?' sign from string? Or do split at that character?
> Getting unicode error if I try to do it:
> 
> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> 1: ordinal not in range(128)
> 
> 
> Thanks, Pet
> 
> script is # -*- coding: UTF-8 -*-

It sounds like you're mixing bytestrings with Unicode strings. I can't
be any more helpful because you haven't shown the code.


From python at mrabarnett.plus.com  Wed Jul  1 20:26:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 01:26:09 +0100
Subject: Getting input the scanf way
In-Reply-To: <8f67b6f80907010133t7f6e2d9eg9ffa3b927d540728@mail.gmail.com>
References: <8f67b6f80907010133t7f6e2d9eg9ffa3b927d540728@mail.gmail.com>
Message-ID: <4A4BFEA1.6020301@mrabarnett.plus.com>

Mr.SpOOn wrote:
> Hi,
> I need to do some kind of interactive command line program.
> 
> I mean: I run the program, it asks me for input, I type something and
> then I get the output or other questions.
> I'm not sure what is the right way to achieve this.
> 
Use raw_input() and print.


From benjamin.kaplan at case.edu  Wed Jul  1 20:27:33 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Wed, 1 Jul 2009 20:27:33 -0400
Subject: What are the limitations of cStringIO.StringIO() ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
Message-ID: <ec96e1390907011727p4cf7ca12y2d4739d6b46c3d4@mail.gmail.com>

On Wed, Jul 1, 2009 at 7:48 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
> Hi,
>
> I think I'm up against a limitation in cStringIO.StringIO(), but could not
> find any clues on the web, especially not in
> http://docs.python.org/library/stringio.html.
>
> What I have is the following function:
>
> ??? def concatenate_files(self,filename_array):
> ??????? import types
>
> ??????? f = cStringIO.StringIO()
> ??????? for filename in filename_array:
> ??????????? log_stream = LogStream(filename)
> ??????????? if not isinstance(log_stream, types.NoneType):
> ??????????????? try:
> ??????????????????? string_ = log_stream.input_file.read()
> ??????????????? except AttributeError, e:
> ??????????????????????? sys.stderr.write("AttributeError: "+str(e)+"\n")
> ??????????????????????? sys.stderr.write("log_stream:
> "+str(log_stream)+"\n")
> ??????????? else:
> ??????????????? return(None)
>
> ??????????? f.write(string_)
> ??????? return (f)
>
> And, when the list of files?- in filename_array - is pointing to long/large
> enough files, I get the exception:
>
> Traceback (most recent call last):
> ? File "svm_ts_tool_in_progress.py", line 244, in OnSelectCell
> ??? self.InspectorViewController(row,col)
> ? File "svm_ts_tool_in_progress.py", line 1216, in InspectorViewController
> ??? self.InspectorePaneGetRecords(self.req_table, rec)
> ? File "svm_ts_tool_in_progress.py", line 1315, in InspectorePaneGetRecords
> ??? log_stream =
> ConcatenatedLogStream(self.events_dict[req_table]["db_dict"].keys())
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 31, in
> __init__
> ??? self.input_file = self.concatenate_files(filename_array)
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 47, in
> concatenate_files
> ??? string_ = log_stream.input_file.read()
> MemoryError
>
> Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
> Could you suggest a better way to create a string that contains the
> concatenation of several big files ?
>

MemoryErrors are caused because, for whatever reason, the OS won't
allocate any more memory for the process. For a 32-bit Windows
process, that maximum is 2 GB. No matter what programming language or
library you use, you can't bypass that limit. There is a way to up the
limit to 3GB but I don't know how to do it. The link below has all the
information about Windows memory limits. If you need lots of really
big strings in memory simultaneously, you'll have to get a 64-bit
system with a ton of RAM.

http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx

> Thanks,
> Ron.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>


From missive at hotmail.com  Wed Jul  1 20:37:40 2009
From: missive at hotmail.com (Lee Harr)
Date: Thu, 2 Jul 2009 05:07:40 +0430
Subject: [ANNC] acromania-0.4
Message-ID: <SNT106-W41BF4D34D308A35248291CB12F0@phx.gbl>


Acromania is a word game of acronyms.

This program is a computer moderator for networked
games of acromania. It can connect to a channel on
IRC, or start a standalone server which can be
accessed much like a MUD.

http://acromania.googlecode.com/


Acromania uses Twisted and SQLite. Optionally, it can
use NLTK to generate computer opponents.

Acromania is released under GPLv3.


Changes in acromania-0.4:
    - autocreate conf.py on first start
    - initialize database on first start
    - add contact information
    - various bug fixes


Notes:
    I have only played the game using the standalone
    server on a secure network. If you have experience
    with programming IRC bots securely, please take
    a look and contact me if you see any problems.

    If you decide to connect it to IRC, please let me
    know, because I'd like to play :o)


_________________________________________________________________
Drag n? drop?Get easy photo sharing with Windows Live? Photos.

http://www.microsoft.com/windows/windowslive/products/photos.aspx


From http  Wed Jul  1 20:48:46 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 17:48:46 -0700
Subject: Trying to use sets for random selection,
	but the pop() method returns  items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <7xhbxvgb9t.fsf@ruckus.brouhaha.com>

Mario Garcia <Mariosky at gmail.com> writes:
> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I

No that's not a good idea.  When the set/dict documentation says you
get the keys in an undetermined order, it doesn't mean the ordering is
random.  It means there is a fixed ordering controlled by the
implementation and not by you.

If you want a random sample, use random.sample().  See the docs for
the random module.


From http  Wed Jul  1 20:49:21 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 17:49:21 -0700
Subject: Trying to use sets for random selection,
	but the pop() method  returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
Message-ID: <7xd48jgb8u.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> Instead, call random.shuffle() on the list, and iterate through that
> to get the elements in random order.

It's better to use random.sample() than random.shuffle().


From sjmachin at lexicon.net  Wed Jul  1 21:20:29 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 1 Jul 2009 18:20:29 -0700 (PDT)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>
	<mailman.2448.1246492219.8015.python-list@python.org>
Message-ID: <f4f1e9c1-c658-4ade-b80f-ec2bad1f2143@r33g2000yqn.googlegroups.com>

On Jul 2, 9:50?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Carl Banks wrote:
> > On Jul 1, 10:56 am, kj <no.em... at please.post> wrote:
> >> For a recovering Perl-head like me it is difficult to understand
> >> why Python's re module offers both match and search. ?Why not just
> >> use search with a beginning-of-string anchor? ?I find it particularly
> >> puzzling because I have this (possibly mistaken) idea that the
> >> Python design philosophy tends towards minimalism, a sort of Occam's
> >> razor, when it comes to language entities; i.e. having re.match
> >> along with re.search seems to me like an "unnecessary multiplication
> >> of entities". ?What am I missing?
>
> > It always seemed redundant to me also (notwithstanding Duncan Booth's
> > explanation of slight semantic differences). ?However, I find myself
> > using re.match much more often than re.search, so perhaps in this case
> > a "second obvious way" is justified.
>
> re.match is anchored at a certain position, whereas re.search isn't. The
> re module doesn't support Perl's \G anchor.

re.search is obstinately determined when it comes to flogging dead
horses:

C:\junk>\python26\python -mtimeit -s"import re" "re.match('xxx',
'y'*100)"
100000 loops, best of 3: 3.37 usec per loop

C:\junk>\python26\python -mtimeit -s"import re" "re.search('^xxx',
'y'*100)"
100000 loops, best of 3: 7.01 usec per loop

C:\junk>\python26\python -mtimeit -s"import re" "re.match('xxx',
'y'*1000)"
100000 loops, best of 3: 3.85 usec per loop

C:\junk>\python26\python -mtimeit -s"import re" "re.search('^xxx',
'y'*1000)"
10000 loops, best of 3: 37.9 usec per loop

C:\junk>


From magawake at gmail.com  Wed Jul  1 21:28:12 2009
From: magawake at gmail.com (Mag Gam)
Date: Wed, 1 Jul 2009 21:28:12 -0400
Subject: Multi thread reading a file
In-Reply-To: <h2eqv3$gpt$4@lust.ihug.co.nz>
References: <mailman.2420.1246413152.8015.python-list@python.org>
	<h2eqv3$gpt$4@lust.ihug.co.nz>
Message-ID: <1cbd6f830907011828i789e1f6fk18ce71da7290f6ee@mail.gmail.com>

LOL! :-)

Why not. I think I will take just do it single thread for now and if
performance is really that bad I can re investigate.

Either way, thanks everyone for your feedback! I think I like python a
lot because of the great user community and wiliness to help!



On Wed, Jul 1, 2009 at 1:07 AM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> In message <mailman.2420.1246413152.8015.python-list at python.org>, Mag Gam
> wrote:
>
>> I am very new to python and I am in the process of loading a very
>> large compressed csv file into another format. ?I was wondering if I
>> can do this in a multi thread approach.
>
> Why bother?
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul  1 21:28:19 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 02 Jul 2009 01:28:19 GMT
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
Message-ID: <pan.2009.07.02.01.28.18@REMOVE.THIS.cybersource.com.au>

On Wed, 01 Jul 2009 17:49:21 -0700, Paul Rubin wrote:

> Carl Banks <pavlovevidence at gmail.com> writes:
>> Instead, call random.shuffle() on the list, and iterate through that to
>> get the elements in random order.
> 
> It's better to use random.sample() than random.shuffle().

Why?


-- 
Steven


From pavlovevidence at gmail.com  Wed Jul  1 21:29:21 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 18:29:21 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com> 
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
Message-ID: <00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>

On Jul 1, 5:49?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > Instead, call random.shuffle() on the list, and iterate through that
> > to get the elements in random order.
>
> It's better to use random.sample() than random.shuffle().

If you're iterating through the whole list and don't need to preserve
the original order (as was the case here) random.shuffle() is better.


Aren't-absolutist-opinions-cool?-ly yr's,

Carl Banks


From http  Wed Jul  1 21:37:38 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 18:37:38 -0700
Subject: Trying to use sets for random selection,
	but the pop() method  returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
Message-ID: <7xr5wzzwyl.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> If you're iterating through the whole list and don't need to preserve
> the original order (as was the case here) random.shuffle() is better.

1. Random.sample avoids iterating through the whole list when it can.

2. Say you want to choose 10 random numbers between 1 and 1000000.

   random.sample(xrange(1000000), 10)

works nicely.  Doing the same with shuffle is painful.


From pavlovevidence at gmail.com  Wed Jul  1 21:46:10 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 18:46:10 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com> 
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
	<7xr5wzzwyl.fsf@ruckus.brouhaha.com>
Message-ID: <5572daf2-7149-41a7-97e5-91c4bc1e908f@n16g2000yqm.googlegroups.com>

On Jul 1, 6:37?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > If you're iterating through the whole list and don't need to preserve
> > the original order (as was the case here) random.shuffle() is better.
>
> 1. Random.sample avoids iterating through the whole list when it can.
>
> 2. Say you want to choose 10 random numbers between 1 and 1000000.
>
> ? ?random.sample(xrange(1000000), 10)
>
> works nicely. ?Doing the same with shuffle is painful.

random.shuffle() is still better when you're iterating through the
whole list as the OP was doing.

Carl Banks


From http  Wed Jul  1 22:02:46 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 19:02:46 -0700
Subject: Trying to use sets for random selection,
	but the pop() method  returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
	<7xr5wzzwyl.fsf@ruckus.brouhaha.com>
	<5572daf2-7149-41a7-97e5-91c4bc1e908f@n16g2000yqm.googlegroups.com>
Message-ID: <7xtz1vu9ix.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> random.shuffle() is still better when you're iterating through the
> whole list as the OP was doing.

The OP wrote:

    I want to select, 70% random records from a List. I thougth set
    where a good idea so I tested this way: ...

That sounds like 70% of the list, not the whole list.  Note that
in addition to using time proportional to the size of the entire
lsit rather than the size of the sample, shuffle() also messes up
the order of the list.  

Why would shuffle ever be better?  It is designed for a different
purpose.  Using a function called "sample" when you want to sample
should be a no-brainer, and if using shuffle instead is ever
preferable, that should be treated as a misfeature in the "sample"
implementation, and fixed.


From pavlovevidence at gmail.com  Wed Jul  1 22:17:56 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 19:17:56 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com> 
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
	<7xr5wzzwyl.fsf@ruckus.brouhaha.com>
	<5572daf2-7149-41a7-97e5-91c4bc1e908f@n16g2000yqm.googlegroups.com>
	<7xtz1vu9ix.fsf@ruckus.brouhaha.com>
Message-ID: <263f472b-3555-4d62-b37d-fb134da5a683@r25g2000vbn.googlegroups.com>

On Jul 1, 7:02?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > random.shuffle() is still better when you're iterating through the
> > whole list as the OP was doing.
> The OP wrote:
>
> ? ? I want to select, 70% random records from a List. I thougth set
> ? ? where a good idea so I tested this way: ...

I was going by his example which went through all the items in the
list.


> That sounds like 70% of the list, not the whole list. ?Note that
> in addition to using time proportional to the size of the entire
> lsit rather than the size of the sample, shuffle() also messes up
> the order of the list. ?
>
> Why would shuffle ever be better?

Because we were talking about different things.


Carl Banks


From rtm74 at yahoo.com  Wed Jul  1 22:38:14 2009
From: rtm74 at yahoo.com (rtm74 at yahoo.com)
Date: Wed, 1 Jul 2009 19:38:14 -0700 (PDT)
Subject: Newby Windows User
Message-ID: <447092.99927.qm@web110201.mail.gq1.yahoo.com>

I am new to Python and use Windows XP. I would like to know how to run a python program file?



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/a5e04ed0/attachment.html>

From bpytlik at Sun.COM  Wed Jul  1 22:48:04 2009
From: bpytlik at Sun.COM (Brock Pytlik)
Date: Wed, 01 Jul 2009 19:48:04 -0700
Subject: System default sys.path
Message-ID: <4A4C1FE4.1070901@sun.com>

Hi, I'm trying to find a way to get the value sys.path would have on a 
particular system if python was started with an empty python path. I do 
want it to include the site specific additional paths. I know I can hack 
this information myself, but I'd rather be able to get this on demand so 
that if things change in the future, I don't have grovel around looking 
for which directory string to change.

If nothing else, I think the following would satisfy my needs:
1) a variable containing the directories to use as a prefix (I think 
sys.exec_prefix and sys.prefix are what I want here)
2) a variable containing the list of suffixes that are applies to the 
prefixes, like lib/python<version>/site-packages
3) a way of handing the *.pth files

Thanks in advance for the help,
Brock


From pavlovevidence at gmail.com  Wed Jul  1 23:18:22 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 20:18:22 -0700 (PDT)
Subject: invoking a method from two superclasses
References: <mailman.2460.1246502951.8015.python-list@python.org>
Message-ID: <24ebfdef-0832-4b78-983a-d886e56160b7@f10g2000vbf.googlegroups.com>

On Jun 30, 9:57?pm, Mitchell L Model <MLMLi... at Comcast.net> wrote:
> [Continuing the discussion about super() and __init__]
>
> The documentation of super points out that good design of
> diamond patterns require the methods to have the same
> signature throughout the diamond. That's fine for non-mixin
> classes where the diamond captures different ways of handling
> the same data.

[snip]

> The problem is that each mixin's __init__ is likely to have a
> different signature.

[snip]


Here are my recommendations for mixin classes.

1. Try to write mixins so that they don't need initializer arguments.
There's several approaches to this.  I prefer to burden the subclass
to set any attributes the mixin needs before calling super().__init__
().

class A(SomeMixin,SomeBaseClass):
    def __init__(self,arg1,arg2):
        self.some_attribute_needed_by_mixin = 10
        super().__init__(arg1,arg2)

That might seem a little weird to some (possibly because it is
impossible in C++ or Java to do that), but I find it to be a far more
versatile way for a subclass to send data to its parent.  I use it for
regular single inheritance, even.

Another possibility is to have a separate mixin initializer that is
called separately.

2. The __init__ of a mixin, if it has one, should always take *args
and **kwargs arguments, and only those arguments, and pass them as-is
to the superclass.

class SomeMixin:
    def __init__(self,*args,**kwargs):
        super().__init__(*args,**kwargs)
        self.use_somehow(self.some_attribute_needed_by_mixin)

If your mixin must have its own initializer argument, make it a
keyword-only argument, and have __init__ pop it off kwargs.

3. List mixin bases first among base classes.


I don't think Python provides an ideal way to do MI, BTW.  I believe
that's by design: MI is somewhat troublesome specifically to
discourage overuse.  As a power MI user, I am fine with this.


> I think I'd be back to having to call each mixin class's
> __init__ explicitly:

I'd say never mix super() and direct calls, for any reason.  Pick one
and go with it.


Carl Banks


From contact at xavierho.com  Wed Jul  1 23:18:42 2009
From: contact at xavierho.com (Xavier Ho)
Date: Thu, 2 Jul 2009 13:18:42 +1000
Subject: Newby Windows User
In-Reply-To: <447092.99927.qm@web110201.mail.gq1.yahoo.com>
References: <447092.99927.qm@web110201.mail.gq1.yahoo.com>
Message-ID: <2d56febf0907012018h79a6ca5bt97d3a900a4b409bf@mail.gmail.com>

Double click should work.

If it flashes up and goes away really quickly, then you need to run it under
IDLE or some kind of python shell.

Once you have Python installed, go to Start -> Run, and type in cmd to bring
up the windows command line or whatever you wanna call it.

Go to the folder where your python script is. Command is the same like macs
or linux, with cd being change directory, and such. Type e: to switch to the
e drive and so on. Note that dir lists the directory and its contents, not
ls like in mac terminals.

When you're in the same folder as your script, type the command like this:

python <file name>.py

That should do the trick. Alternatively, you can type in python and start
the python shell in the same folder.

Then you can just do import and whatever you like. :]

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Thu, Jul 2, 2009 at 12:38 PM, <rtm74 at yahoo.com> wrote:

> I am new to Python and use Windows XP. I would like to know how to run a
> python program file?
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/83fd59df/attachment.html>

From wuwei23 at gmail.com  Wed Jul  1 23:41:19 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:41:19 -0700 (PDT)
Subject: Using Python to set desktop background image under Windows XP
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net> 
	<mailman.2456.1246494790.8015.python-list@python.org>
Message-ID: <ef3c772d-d935-4241-8809-c306eae21747@g19g2000yql.googlegroups.com>

On Jul 2, 8:02?am, "ELLINGHAUS, LANCE" <lance.ellingh... at hp.com>
wrote:
> Does anyone have any code that would allow setting the desktop background image under Windows XP?

It's amazing what typing "python windows desktop" into Google will
find you:

http://snippets.dzone.com/posts/show/3348

Any other searches you'd like us to do?

(Also: please post a new message instead of replying to an existing
one and changing the subject, it screws up threading)



From wuwei23 at gmail.com  Wed Jul  1 23:47:46 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:47:46 -0700 (PDT)
Subject: Getting input the scanf way
References: <mailman.2438.1246467374.8015.python-list@python.org>
Message-ID: <fcc576d0-46d7-4522-bfae-c60d53fb55fa@g1g2000yqh.googlegroups.com>

On Jul 1, 6:33?pm, "Mr.SpOOn" <mr.spoo... at gmail.com> wrote:
> I need to do some kind of interactive command line program.
>
> I mean: I run the program, it asks me for input, I type something and
> then I get the output or other questions.
> I'm not sure what is the right way to achieve this.

While the simplest way would be raw_input & print, as suggested,
there's also the cmd[1] module in the stdlib, which is what the
standard CPython interpreter uses, I believe.

[1]: http://docs.python.org/library/cmd.html


From no.email at please.post  Wed Jul  1 23:49:57 2009
From: no.email at please.post (kj)
Date: Thu, 2 Jul 2009 03:49:57 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
Message-ID: <h2hap5$qv8$2@reader1.panix.com>

In <Xns9C3BCA27ABC36duncanbooth at 127.0.0.1> Duncan Booth <duncan.booth at invalid.invalid> writes:
>So, for example:

>>>> re.compile("c").match("abcdef", 2)
><_sre.SRE_Match object at 0x0000000002C09B90>
>>>> re.compile("^c").search("abcdef", 2)
>>>>

I find this unconvincing; with re.search alone one could simply
do:

>>> re.compile("^c").search("abcdef"[2:])
<_sre.SRE_Match object at 0x75918>

No need for re.match(), at least as far as your example shows.

Maybe there are times when re.match() is more "convenient" in some
way, but it is awfully Perlish to "multiply language elements" for
the sake of this trifling convenience.

kynn


From wuwei23 at gmail.com  Wed Jul  1 23:53:37 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:53:37 -0700 (PDT)
Subject: Open Source RSS Reader in Python?
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <425d611e-ee56-4def-875e-899b2753eeb4@a7g2000yqk.googlegroups.com>

On Jul 2, 9:18?am, Alex <alex.lavoro.pro... at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?

It's always worth taking a look at PyPI. Some packages work perfectly
well as stand alone applications.

http://pypi.python.org/pypi?%3Aaction=search&term=rss&submit=search

These two look promising:
+ NewsFeed (Tk-based): http://home.arcor.de/mdoege/newsfeed/
+ urssus (QT-based): http://code.google.com/p/urssus/


From wuwei23 at gmail.com  Wed Jul  1 23:56:28 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:56:28 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com> 
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com> 
	<mailman.2434.1246465610.8015.python-list@python.org>
	<npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>
Message-ID: <1e79b6bf-f33e-4267-bc61-dde6093a95e1@r33g2000yqn.googlegroups.com>

On Jul 2, 3:47?am, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> And even simpler:
> ? ? ?PASSWORD = "qwerty"
> ? ? ?MAXRETRY = 3
> ? ? ?for attempt in range(MAXRETRY):
> ? ? ? ? ?if raw_input('Enter your password: ') == PASSWORD:
> ? ? ? ? ? ? ?print 'Password confirmed'
> ? ? ? ? ? ? ?break # this exits the for loop
> ? ? ? ? ?print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
> ? ? ?else:
> ? ? ? ? ?# The else for a for statement is not executed for breaks,
> ? ? ? ? ?# So indicates the end of testing without a match
> ? ? ? ? ?raise SystemExit # Or whatever you'd rather do.

Nice one, I always forget about for-else :)


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  2 00:14:36 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 02 Jul 2009 04:14:36 GMT
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
Message-ID: <pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>

On Thu, 02 Jul 2009 03:49:57 +0000, kj wrote:

> In <Xns9C3BCA27ABC36duncanbooth at 127.0.0.1> Duncan Booth
> <duncan.booth at invalid.invalid> writes:
>>So, for example:
> 
>>>>> re.compile("c").match("abcdef", 2)
>><_sre.SRE_Match object at 0x0000000002C09B90>
>>>>> re.compile("^c").search("abcdef", 2)
>>>>>
>>>>>
> I find this unconvincing; with re.search alone one could simply do:
> 
>>>> re.compile("^c").search("abcdef"[2:])
> <_sre.SRE_Match object at 0x75918>
> 
> No need for re.match(), at least as far as your example shows.

Your source string "abcdef" is tiny. Consider the case where the source 
string is 4GB of data. You want to duplicate the whole lot, minus two 
characters. Not so easy now.


> Maybe there are times when re.match() is more "convenient" in some way,
> but it is awfully Perlish to "multiply language elements" for the sake
> of this trifling convenience.

No, it's absolutely Pythonic. 


>>> import this
...
Although practicality beats purity.



-- 
Steven


From rajat.dudeja at gmail.com  Thu Jul  2 00:33:55 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Wed, 1 Jul 2009 21:33:55 -0700 (PDT)
Subject: Access NtQueryInformationProces() from Python
References: <408014003A0DA34BA5287D7A07EC089A1F94F4@EVS1.aeroflex.corp> 
	<mailman.2365.1246353019.8015.python-list@python.org>
Message-ID: <5e107810-2378-41fc-8fb5-329a943ab3bd@t13g2000yqt.googlegroups.com>

On Jun 30, 2:10?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Dudeja, Rajat wrote:
> > Hi,
>
> > I'm looking for a way to call the NtQueryInformationProces() and ReadProcessMemory() of WindowsXP from Python.
>
> > Can anyone direct me to some examples where they have been successfully called through Python?
>
> You want to look at ctypes:
>
> http://docs.python.org/library/ctypes.html?highlight=ctypes#module-ct...
>
> TJG

Thanks Tim


From david.lyon at preisshare.net  Thu Jul  2 00:40:25 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Thu, 02 Jul 2009 00:40:25 -0400
Subject: System default sys.path
In-Reply-To: <4A4C1FE4.1070901@sun.com>
References: <4A4C1FE4.1070901@sun.com>
Message-ID: <81a8195ca5ecf44f3bf9ddbfaae37bdc@preisshare.net>

On Wed, 01 Jul 2009 19:48:04 -0700, Brock Pytlik <bpytlik at Sun.COM> wrote:
> Hi, I'm trying to find a way to get the value sys.path would have on a 
> particular system if python was started with an empty python path. I do 
> want it to include the site specific additional paths. I know I can hack 
> this information myself, 

Copy the code out from site.py...


> but I'd rather be able to get this on demand so 
> that if things change in the future, I don't have grovel around looking 
> for which directory string to change.

            for index in range(len(sys.path)):
                del sys.path[0]
            site.addsitedir(self.p.python_sitepackages_path)

> If nothing else, I think the following would satisfy my needs:
> 1) a variable containing the directories to use as a prefix (I think 
> sys.exec_prefix and sys.prefix are what I want here)
> 2) a variable containing the list of suffixes that are applies to the 
> prefixes, like lib/python<version>/site-packages
> 3) a way of handing the *.pth files

What way do you want to handle them?




From stefan_ml at behnel.de  Thu Jul  2 00:50:54 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Thu, 02 Jul 2009 06:50:54 +0200
Subject: Multi thread reading a file
In-Reply-To: <mailman.2433.1246465455.8015.python-list@python.org>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>	<op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2433.1246465455.8015.python-list@python.org>
Message-ID: <4a4c3cae$0$31873$9b4e6d93@newsspool3.arcor-online.net>

Mag Gam wrote:
> On Wed, Jul 1, 2009 at 12:54 AM, Gabriel Genellina wrote:
>> Does the format conversion involve a significant processing time? If not,
>> the total time is dominated by the I/O time (reading and writing the file)
>> so it's doubtful you gain anything from multiple threads.
> 
> The format does inolve significant time processing each line.
>
>>> Here is the pseudo code I was thinking about:
>>>
>>> Let T  = Total number of lines in a file, Example 1000000 (1 million
>>> files)
>>> Let B = Total number of lines in a buffer, for example 10000 lines
>>>
>>>
>>> Create a thread to read until buffer
>>> Create another thread to read buffer+buffer  ( So we have 2 threads
>>> now. But since the file is zipped I have to wait until the first
>>> thread is completed. Unless someone knows of a clever technique.
>>> Write the content of thread 1 into a numpy array
>>> Write the content of thread 2 into a numpy array
>> Can you process each line independently? Is the record order important? If
>> not (or at least, some local dis-ordering is acceptable) you may use a few
>> worker threads (doing the conversion), feed them thru a Queue object, put
>> the converted lines into another Queue, and let another thread write the
>> results onto the destination file.
> 
> Yes, each line can be independent. The original file is a time series
> file which I am placing it into a Numpy array therefore I don't think
> the record order is important.  The writing is actually done when I
> place a value into a "dset" object.
> 
> Let me show you what I mean.
> reader=csv.reader(open("100000.csv"))

Have you tried if using the csv reader here is actually fast enough for
you? Maybe you can just .split(',') each line or something (no idea what
else the csv reader may do, but anyway...)


> for s,row in enumerate(reader):
>  if s!=0 and s%bufsize==0:
>       dset[s-bufsize:s] = t  #here is where I am writing the data to
> the data structure. Using a range or broadcasting.

Erm, what's "t"? And where do you think the "significant" processing time
comes from in your example? From your code, that's totally non-obvious to me.


>   #15 columns
>  if len(row) != 15:
>    break
> 
>  t[s%bufsize] = tuple(row)
> 
> #Do this all the way at the end for flushing.
> if (s%bufsize != 0):
>    dset[(s//bufsize)*bufsize:s]=t[0:s%bufsize]

If you *really* think your code is not I/O bound, but that the code for
writing the data into the NumPy array is the slow part (which I actually
doubt, but anyway), you can try writing your code in Cython, which has
direct support for writing to NumPy arrays through their buffer interface.

http://docs.cython.org/docs/numpy_tutorial.html

Stefan


From apt.shansen at gmail.com  Thu Jul  2 01:11:10 2009
From: apt.shansen at gmail.com (Stephen Hansen)
Date: Wed, 1 Jul 2009 22:11:10 -0700
Subject: What are the limitations of cStringIO.StringIO() ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
Message-ID: <7a9c25c20907012211m610dac7dr3c18c33ea33f0ed6@mail.gmail.com>

>
>
>    1. Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
>    2. Could you suggest a better way to create a string that contains the
>    concatenation of several big files ?
>
>
This isn't a limit in cStringIO.StringIO, but a limit on the amount of
memory a process is able to allocate from the OS. There's no real way
around it-- but you can take a different approach.

You have to get the memory somewhere, but if what you're combining
can't fit into memory (generally, 2 GB, but it depends on OS and
platform), you can use memory from a different source-- the hard-drive
for instance.

I would suggest you create a temporary file somewhere, and instead of
reading the contents into memory, read it in chunks and write it to
this temporary file, then go on and do the rest. That way you'll never
have so much in memory that you hit the limits. When this is done, you
can move this temporary file to where you want it, or read from it and
pass its output somewhere.

--S
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/36980e11/attachment.html>

From tjreedy at udel.edu  Thu Jul  2 01:25:05 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 02 Jul 2009 01:25:05 -0400
Subject: Adding an object to the global namespace through " f_globals"
	is   that allowed ?
In-Reply-To: <4A4BC22D.70502@gmail.com>
References: <4A4BC22D.70502@gmail.com>
Message-ID: <h2hgbj$sp5$1@ger.gmane.org>

Stef Mientki wrote:
> hello,
> 
> I need to add an object's name to the global namespace.
> The reason for this is to create an environment,
> where you can add some kind of math environment,
> where no need for Python knowledge is needed.
> 
> The next statement works,
> but I'm not sure if it will have any dramatical side effects,
> other than overruling a possible object with the name A
> 
> def some_function ( ...) :
>      A = object ( ...)
>      sys._getframe(1).f_globals [ Name ] = A

global name
name = A

or is name is a string var
globals()[name] = A



From esj at harvee.org  Thu Jul  2 01:30:16 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Thu, 02 Jul 2009 01:30:16 -0400
Subject: pep 8 constants
In-Reply-To: <4A4A3FC1.5000108@tim.thechases.com>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>
	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>
	<4A48E307.50804@harvee.org> <4A49E232.6090101@tim.thechases.com>
	<4A4A2EE5.8040301@harvee.org> <4A4A3FC1.5000108@tim.thechases.com>
Message-ID: <4A4C45E8.9070309@harvee.org>

Tim Chase wrote:
>> I've tried it least two dozen editors and they all fail miserably
>> because they're focused on keyboard use (but understandable)
> [...snip...]
>> I've tried a whole bunch, like I said at least a dozen. They
>> all fail for first reasons such as inability to access all
>> functionality through keystrokes (easiest interface method
>> from speech recognition)
> 
> I'm not sure I follow which you want...you kvetch that
> they're too focused on keyboard use, but then that you can't
> access all functionality through the keyboard.

sorry. I've been living in this world for so long that I sometimes forget to
explain what's obvious inside my head. I apologize for the confusion.

The apparent conflict arises because the same term (keyboard access) is used to
describe two different problems. In the first case, the user interface model
(how you access taxes, manipulate light which (language) constructs are designed
to be efficient for your hands.  speech recognition users need an editor that
supports constructs that are efficient for the voice. One such construct is the
ability to navigate or operate on language elements by name. I've used some of
them before such as predicate, index, first method etc.

The second problem is that editors are designed to be driven by keystroke. If I
had a cross  process boundary APIPaula I can simply call the editor function to
perform to give operation. Unfortunately, today my speech recognition
environment needs to generate keystrokes to access functionality. for example,
in Emacs, when I say "delete word", the macro and marmot emits M-d

> 
> [warning, blatant vim fanaticism follows]
> 
> I use vim and can't remember the last time I used the mouse
> with it (save for occasionally lazily scrolling with the
> mouse-wheel, but you can scroll with the keyboard too), so
> it meets your "must be fully accessible through the
> keyboard" constraint.  It also has single keystroke commands
> for indenting/exdenting the current line as you mention:

you are forgiven. :-) try this experiment. Bring up the buffer full Python code
code you value them, starting in command mode, close your eyes and type a random
word. While your eyes are closed, undo that word. Every time I've tried it the
results have been mildly disastrous. If you been paying attention, I've tried to
leave speech recognition errors in place whatever didn't impede understanding
(too much) but, remember I'm getting one error in 20 errors is on average. That
means, I'll be correcting the IE errors, potentially much more dangerous errors
are regular basis. Any energy use by speech recognition must be able to cope
with a random dictation errors and let the user recover gracefully. Again, until
I started using speech recognition, I would never would've thought of this as a
failure case.

> 
>   > I know this is also counter to the Python way but having
>   > something marking and outdent would be really useful so
>   > that a vocal driven command to indent or outdent a block
>   > would be practical.
> 
> which can be done in insert-mode with control+D, control+T,
> and if you want to clear all indentation (all the way back
> to the first column), you can use "0" followed by control+D.
> Vim also allows for fairly detailed control over
> auto-indentation settings so you can match them to your
> preferences.  I suspect Emacs may be configurable to offer
> similar functionality but I'd have to defer to the emacsen
> on the list.

Yes, Emacs will, a single tab key, tab view to the indentation level specified
by the previous line unless it's already there and then it will start inventing
further. This really sucks. Sometimes, you just weary and then to  (you just
want to) go to the right place and stay there
> 
> That said, I'll be the first to admit that the vi/vim
> learning curve is more like a brick wall than a curve.
> However, I find the efficiency gains abundantly than repaid
> the time I invested to learn it well.

Yeah, I first encountered the eye in 1985. Or maybe I should say VI (Roman
numeral six).
> 
>>> Dasher[1]
>>
>> I've tried it, it's quite promising but my hands term are sufficiently
>> that I can't target accurately.
> 
> Last I tried it, it scaled the target sizes based on
> probability.  You might also try unconventional pointing
> devices for better precision.  I've seen web-cam
> eye-tracking tools which might make it a bit easier.  Or try
> a tablet input (where the motion corresponds linearly, as
> opposed to accelerated mouse motion).  Such input options
> are listed on the Dasher website, at least for those they
> tested.
> 

I like tablets. I need to buy a new one. We only problem is that most pens for
tablets are a little bit too small and hard for my hands (although they are much
better than mice). The major downfall is the buttons on the pen shaft. Damn
that's awkward to reach. I think it would need a separate tab of three buttons
that I can click and double-click independent of the pen controls.

>> Oh, another failure point. Have you ever tried to selected beach and
>> by voice. I mean I should say have you ever tried to
>> select a region by voice.
> 
> yes, not a pleasant experience.  Again, vim's modal
> interface allows for using text-objects so you can issue
> short-hand commands like
> 
>   ci"
> 
> to "[c]hange the contents [i]nside the double-quotes I'm
> currently on/withing".  The operator+motion and
> operator+textobject command syntax obviates a lot selection.
> While vim does offer a "visual" mode (akin to selection in
> other editors), I use it much less because of the power
> provided by the operator+[motion/textobject].

that's getting close to what I want to do with voice command except instead of
cryptic sequence of characters, I would say something like

string_edit = edit [<which>] string
which = first | second | third | fourth | fifth | sixth


> as you're an emacs user, my vim suggestions may sound like
> heresy. ;-)  But I suspect a skilled emacs user (or perhaps
> asking on an emacs-users list) could mimic much of the vim
> functionality.  I just can't be of much assistance there.

I really don't care what editor I use as long as it gets the job done. I have
strong preferences for always insert mode but, if I had an editor I had no
keystroke commands and everything I type went into the buffer but I committed a
complete of my speech, that would be kind of cool.
> 
> You're welcome to move it off-list...it's kinda drifted from python to
> general accessibility issues.  CC'ing c.p.l for this one in case any
> emacsen care to chime in on their suggested tweaks.

well, that you are really joined. For example, if we look at the string edit
command above, that implies he had or has the ability to properly distinguish a
string in a line of code. Think of how many ways you can express a string
triple or single quotes into different forms sometimes with  quotes nested
inside.  then take the whole object instance and know method is possible with
its type signature. This is editor work.


From Mariosky at gmail.com  Thu Jul  2 01:33:25 2009
From: Mariosky at gmail.com (Mario Garcia)
Date: Wed, 1 Jul 2009 22:33:25 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <05dde563-a8f1-45d1-8f59-7740c58787ba@e21g2000yqb.googlegroups.com>


Thank you all for your input, Yes random is what I need!!
I checked the docs, and follow your comments, I will use both
random.sample and random.shuffle,and random.choice etc. !!

For this particular problem I think ramdom.shuffle() is what I need.

I was not very clear or complete in my explanation, and  I didn't
expect such a
discussion on my needs, now I'm embarrassed :) .

The list is a data set for training a machine learning algorithm. I
want to
use 70% of the records (random) for training, but then the remaining
30% are used for
validation. This is repeated a few times choose again 70% at random
for training and
the rest for validation.

With random.shuffle() I just iterate for the first 70% of the records
for training and
I just continue with the remaining 30%. This last 30% we dont care if
its random anymore,
so shuffle is doing some extra work as it was pointed out.
Conceptually something like this:

population = range(100)
training = random.sample(population,70)
validation = set(population).difference(set(training))

But I think this is more costly

Thanks Again
Mario


From rajat.dudeja at gmail.com  Thu Jul  2 01:42:43 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Wed, 1 Jul 2009 22:42:43 -0700 (PDT)
Subject: Accessing windows structures through ctypes.
Message-ID: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>

Hi,

Using ctypes can I access the windows structures like:

PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
PEB_LDR_DATA, etc?


Regards,
Rajat



From esj at harvee.org  Thu Jul  2 01:47:28 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Thu, 02 Jul 2009 01:47:28 -0400
Subject: pep 8 constants
In-Reply-To: <op.uwbx3lwla8ncjz@gnudebst>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<mailman.2273.1246252100.8015.python-list@python.org>	<a5a4183c-1dd0-40b2-bdf4-5895488c165c@t21g2000yqi.googlegroups.com>	<mailman.2306.1246290580.8015.python-list@python.org>	<025949cb$0$20671$c3e8da3@news.astraweb.com>	<4A497A5B.4040503@harvee.org>
	<op.uwbxt1wfa8ncjz@gnudebst> <op.uwbx3lwla8ncjz@gnudebst>
Message-ID: <4A4C49F0.5060306@harvee.org>

Rhodri James wrote:
> 
> Gah.  Ignore me.  I hit 'send' instead of 'cancel', after my musings 
> concluded that yes, an editor could be smart enough, but it would have to
> embed a hell of a lot of semantic knowledge of Python and it still wouldn't
> eliminate the need to speak the keyboard at times.

imagine having the same problem except that happens at random while you're
speaking and watching something else other than a screen. :-)

Yeah, it would take a lot of semantic knowledge about Python. Is it possible to
leverage compiler internals? Is it possible to gather as much information as you
can and when the system says "I don't know" you tell what you know it remembers
that for future reference?

And you're right, they're always corner cases where you'll need to speak the
keyboard or type. I've mostly resigned to accept on days when I have an absolute
hissy hissy fit because my hands hurt so bad I can't get enough painkillers
drop the pain and let me function.

In the real short term what I really want. More than anything right now is to
get back to the point where I can  pick away at writing Python again. I'm in
this really weird confluence of virtual machine hell,  the evolution of
naturally speaking under wine and the problems of telling an editor how to do
the right thing.

There's a gap between the fragile crappy way I and others operate today and the
really ideal completely voice driven  environment that exists between my ears. I
would like to move into that gap but it's sufficiently far away from what my
hands can do that I'm dependent on others and that makes me  really crazy sometimes.

>From my perspective, what I consider a reasonable intermediate step would be an
editor that has the following features:

The ability to select regions either by NaturallySpeaking Select-and-Say and
Emacs mark and point semantics.
Very deterministic indentation control. (I.e. indent x tabs or indent to "right"
level.)
ability to navigate/operate on generic language features
it would be nice if one could edit language features in a separate window again,
using Select-and-Say type interface.
another it would be nice would be the ability to look up type signatures
(classes, methods etc. and inject the appropriate template when using a
particular method. (Doesn't have to be by voice)


this level of functionality, would also make it possible to comply with PEP-8
:-) given proper easy and automatic name generation and dumpling.


From ldo at geek-central.gen.new_zealand  Thu Jul  2 01:53:09 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Thu, 02 Jul 2009 17:53:09 +1200
Subject: Making code run in both source tree and installation path
References: <mailman.2310.1246292443.8015.python-list@python.org>
	<5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>
	<mailman.2428.1246465065.8015.python-list@python.org>
Message-ID: <h2hi05$3ec$2@lust.ihug.co.nz>

In message <mailman.2428.1246465065.8015.python-list at python.org>, Robert 
Kern wrote:

> On 2009-07-01 01:04, Carl Banks wrote:
>>
>> The most common way I've seen people work around this issue is to
>> throw their data files into the package directories.  Yuck.
> 
> Huh. I always found that to be a more elegant solution than hardcoding the
> data location into the program at install-time.

Think in terms of a portable OS, written to run on multiple architectures. 
Read-only data is architecture-dependent, that's why it pays to separate it 
from the code.

Otherwise you end up with a system that needs a reinstall every time the 
hardware changes.




From wuwei23 at gmail.com  Thu Jul  2 02:09:13 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 23:09:13 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com> 
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com> 
	<mailman.2434.1246465610.8015.python-list@python.org>
	<npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net> 
	<1e79b6bf-f33e-4267-bc61-dde6093a95e1@r33g2000yqn.googlegroups.com> 
	<mailman.2466.1246512006.8015.python-list@python.org>
Message-ID: <19cbe70f-d9a0-4c77-b02a-98b943b063b7@o6g2000yqj.googlegroups.com>

Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
> ? ? ? ? There is also the getpass module to play with!

I don't think I've ever seen getpass, so thanks for pointing that out.
Unfortunately, it wouldn't have helped the OP understand why his
original code wasn't working ;)


From tkjthingone at gmail.com  Thu Jul  2 02:10:43 2009
From: tkjthingone at gmail.com (Horace Blegg)
Date: Wed, 1 Jul 2009 23:10:43 -0700
Subject: Accessing windows structures through ctypes.
In-Reply-To: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
Message-ID: <b78ad4bc0907012310w31e50429k10ac80dfa928e8b7@mail.gmail.com>

http://www.codeproject.com/KB/threads/GetNtProcessInfo.aspx

Looks rather to be pretty simple: Acquire the PED base pointer (article
explains how) and then just read that information into a struct using
ReadProcessMemory().

On Wed, Jul 1, 2009 at 10:42 PM, Rajat <rajat.dudeja at gmail.com> wrote:

> Hi,
>
> Using ctypes can I access the windows structures like:
>
> PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> PEB_LDR_DATA, etc?
>
>
> Regards,
> Rajat
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/30df6b5b/attachment.html>

From shenyute at gmail.com  Thu Jul  2 02:11:54 2009
From: shenyute at gmail.com (Shen, Yu-Teh)
Date: Wed, 1 Jul 2009 23:11:54 -0700 (PDT)
Subject: dealloc function in python extend c module
Message-ID: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>

I create my extend type something like http://www.python.org/doc/current/extending/newtypes.html.
And my type has a member which is a pointer point to my allocate
memory ( no ref count).
ex:
---------------------------------------------------
typedef struct {
    PyObject_HEAD
    /* Type-specific fields go here. */
    mytype *p;
} noddy_NoddyObject;

And i write dealloc function like this:
---------------------------------------------------
static void
Noddy_dealloc(Noddy* self)
{
    delete p;
    self->ob_type->tp_free((PyObject*)self);
}

And I found it's strange that it didn't call dealloc when there is no
reference.

ex:
a = Noddy()
b = a
del a
del b
# i think there is no ref to the object, and it should call dealloc
but it didn't call!!!

could anyone tell me what happened?

Thanks a lot!!



From pm567426 at gmail.com  Thu Jul  2 02:13:52 2009
From: pm567426 at gmail.com (Pedram)
Date: Wed, 1 Jul 2009 23:13:52 -0700 (PDT)
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
Message-ID: <9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>

On Jul 1, 10:01?pm, Christian Heimes <li... at cheimes.de> wrote:
> Pedram schrieb:
>
> > Hello community,
> > I'm reading the CPython interpreter source code,
> > first, if you have something that I should know for better reading
> > this source code, I would much appreciate that :)
> > second, in intobject.c file, I read the following code in
> > fill_free_list function that I couldn't understand:
> > <code>while (--q > p)
> > ? ? Py_TYPE(q) = (struct _typeobject *)(q-1);
> > Py_TYPE(q) = NULL;
> > </code>
> > What does it mean?
>
> The code is abusing the ob_type member to store a single linked, NULL
> terminated list of free integer objects. It's a tricky optimization you
> don't have to understand in order to understand the rest of the code.
>
> And no, the code in ctypes.h is totally unrelated to the free list in
> intobject.c.
>
> Christian

Thanks for reply.
I totally understood the fill_free_list() function. Thanks.
But I have problems in understanding the PyInt_FromLong(). Here's the
code:

PyObject *
PyInt_FromLong(long ival)
{
	register PyIntObject *v;
#if NSMALLNEGINTS + NSMALLPOSINTS > 0
	if (-NSMALLNEGINTS <= ival && ival < NSMALLPOSINTS) {
		v = small_ints[ival + NSMALLNEGINTS];
		Py_INCREF(v);
#ifdef COUNT_ALLOCS
		if (ival >= 0)
			quick_int_allocs++;
		else
			quick_neg_int_allocs++;
#endif
		return (PyObject *) v;
	}
#endif
	if (free_list == NULL) {
		if ((free_list = fill_free_list()) == NULL)
			return NULL;
	}

	v = free_list; // <-- No problem till here :)
	free_list = (PyIntObject *)Py_TYPE(v);
	PyObject_INIT(v, &PyInt_Type);
	v->ob_ival = ival;
	return (PyObject *) v;
}

I understood that small numbers (between -5 and 256) are referenced to
small_ints list. Others have to store in PyIntBlock, am I right? OK,
no problem till 'v = free_list;' but can't understand the line
'free_list = (PyIntObject *)Py_TYPE(v);' :(. Where free_list
referenced to? Don't this correct that free_list have to be referenced
to another free block so next time the function called v store in this
location?
Sorry for my bad English. I hope you could understand me :)


From israelu at elbit.co.il  Thu Jul  2 02:17:00 2009
From: israelu at elbit.co.il (iu2)
Date: Wed, 1 Jul 2009 23:17:00 -0700 (PDT)
Subject: wxPython: Plaing widgets in status bar
Message-ID: <335b69b5-eabe-443e-842d-fb6ec95a3bd3@x3g2000yqa.googlegroups.com>

Hi all,

I try to placs widgets (button, static text labels) in a status bar,
wxPython.
>From the examples I could place them using exact positioning by the
status bar methof GetFieldRect.
In this case I need to add an EVT_SIZER handler to keep the widgets in
their propotional places
within the status bar.

I try to do it without exact positioning, that is using a sizer.
I tried adding a sizer directly to the status bar, but it didn't work,
it layed out the widgets
at the upper left corner of the status bar, atop of each other.
I tried adding a panel to the status bar and then adding the widgets
to it., but then the widgets partially
cover the status bar. They also don't keep their propotional
positions, although I used it in the sizer.Add method.

How can I position widgets within the status bar like positioning them
in a frame?

thanks


From wuwei23 at gmail.com  Thu Jul  2 02:25:38 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 23:25:38 -0700 (PDT)
Subject: Accessing windows structures through ctypes.
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
Message-ID: <eac94481-c76b-46f8-bac6-48794fc264af@d4g2000yqa.googlegroups.com>

On Jul 2, 3:42?pm, Rajat <rajat.dud... at gmail.com> wrote:
> Using ctypes can I access the windows structures like:
>
> PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> PEB_LDR_DATA, etc?

ctypes.wintypes lists all of the Windows structures included with the
module.

You should be able to use ctypes.Structure class to roll your own:

http://docs.python.org/library/ctypes.html#structured-data-types
http://code.activestate.com/recipes/208699/
http://msdn.microsoft.com/en-us/library/ms684855(VS.85).aspx



From esj at harvee.org  Thu Jul  2 02:33:10 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Thu, 02 Jul 2009 02:33:10 -0400
Subject: pep 8 constants
In-Reply-To: <pan.2009.06.30.05.45.18@REMOVE.THIS.cybersource.com.au>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<mailman.2273.1246252100.8015.python-list@python.org>	<a5a4183c-1dd0-40b2-bdf4-5895488c165c@t21g2000yqi.googlegroups.com>	<mailman.2306.1246290580.8015.python-list@python.org>	<025949cb$0$20671$c3e8da3@news.astraweb.com>	<mailman.2352.1246329493.8015.python-list@python.org>
	<pan.2009.06.30.05.45.18@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A4C54A6.9030707@harvee.org>

Steven D'Aprano wrote:
> That assumes that every word is all caps. In practice, for real-life 
> Python code, I've tripled the vocal load of perhaps one percent of your 
> utterances, which cuts your productivity by 2%.
> 
> If you have 10000 words in you per day, and one percent get wrapped with 
> a leading and trailing "capslock", you have:
> 
> 9900 regular words plus 100 constants
> 
> versus
> 
> 9700 regular words plus 100 constants plus 200 by capslock.
> 
> Your productivity goes down by 200 words out of 10,000, or two percent.

oh I wish it was so simple. I would absolutely you if it was that simple the
real world. Somehow, I fear that you wouldn't understand unless you sat next to
me and watch me try to write code to  a variety of standards.

In practice, my experience says that with a really good  speech driven
environment for programming, IT, vocal load probably by a quarter to a half and
be more compliant with current fashion for naming.
> 
> 
>>>> Heck, have you ever noticed how most Python smart editors can't even
>>>> indent properly according to local contexts. Emacs is the only one and
>>>> even that one sometimes fails
>>> I use kwrite for editing, and I can't say I've ever noticed a failure.
>> okay, it fails from a speech recognition user perspective. Put the
>> cursor on the line and hit the tab key. Insert spaces/tabs in the line
>> of text. Not good for speech recognition. If  mess of indentation and
>> hit the tab key, it doesn't automatically indent to the right location.
>> I'll be damned if I'm in the sit there speaking
>> "tabkeytabkeytabkeytabkeytabkey" because the error should take care of
>> it for me and save my voice. Like I said, Emacs does it correctly and
>> nobody else does as far as I can tell.
> 
> I don't understand what you're describing.
> 
> If you set kwrite to use "Python style" indent mode, then starting a new 
> line will automatically indent to either the current indent level, or one 
> extra indent level if the line ends with a colon. You shouldn't need to 
> indent forward more than one level at a time when writing Python code, 
> although you will need to dedent multiple levels on occasion.

I recognize your confusion. It's very common when describing this problem. If I
had some way of making a movie of what  and describing, obviously be more clear.
I'll see if I can make a movie with my camera that demonstrates the problem.  It
probably won't happen fast but, what I tried your editor, it failed   with a
trivial effort.  I think I just hit the tab key multiple times in different
places on the line. In all cases it did the wrong thing. For me, the right thing
is to force the line to the right indentation based on the previous line to
matter how may times you get the tab key or where you are on that line when you
hit the tab key. I could be in the middle of the line, the end of line, start a
line, the start of the string and if I hit a tab key, that line should go to
exactly the right place stayed there no matter how me more times I typed a tab key.

But this might be what you're getting confused. What I'm really asking for is
the ability to say "force indent" and have the line indent exactly correctly
based on context. It doesn't have to be the tab key. The tab key is the method
of convenience.

> 
>> You're looking at it from the classical anti-accommodation perspective.
>> Don't change the convention, give us the tools so we can comply with
>> what the rest of you do. 
> 
> Just a minute. You're the one who started this discussion rejecting the 
> convention. Your first post started off:
> 
> "I reject this convention..."
> 
> and then finished with
> 
> "so I reject pep 8 because I have no voice safe alternative"
> 
> Do you blame us for reading this as a protest against uppercase 
> identifiers?

it's a protest against  identifiers that increase vocal or hand load.  It's also
protest against decisions people make without awareness of the implications, in
this case, increasing the barriers against disabled programmers.

> 
> Now you're saying you're happy for us to keep the all-uppercase 
> convention and just want better tools. Okay, you want better tools. 
> Great. If you're attempting to raise the profile of disabled programmers, 
> you've done so, but what exactly are you expecting?

I waffle back and forth on that. I recognize my opinion  matters as much as a
piss hole in the snow. But the unintentional discrimination really gets to me.
In case you're wondering, I feel this way about many forms of bad
design/exclusionary practices. Some I can even do something about.

my expectations are evolving. I wanted to raise awareness, like you said, I've
done that. But now, I'd like to turn it into action. As I said in another post,
the editor that would let me get back to writing Python relatively easily again
doesn't exist. It's not the flashy wonderful no keystrokes whatsoever condition
but it's significantly better than the current Emacs/VI/Python editor du jour.
it would be able to operate open loop with relation to speech recognition but I
also have an idea of how to add closed loop capability to make it more efficient
as that capability becomes available.

> I've already said it's your right to reject the convention for your own 
> code. Go right ahead. This is only a problem if you're editing other 
> people's code which is using uppercase constants.

exactly. If I'm unable to comply with local conventions, I cannot work within an
organization and be an active member of the team. This is one example of what I
mean by unintentional discriminatory effects of a given decision.  rhetorical
devices aside, I think the right way to deal with accessibility issues and
decisions leading to discrimination is to make the appropriate tools if possible
for the individual. But I'm sure that would be a very long discussion we would
have over a couple of beers.

> 
> You've rejected capslock red capslock because it takes three utterances, 
> but said you use constant_red instead. That's two utterances, saving you 
> only one. If you actually have to say the underscore, your convention 
> takes six syllables versus five for my idea.

 my opinion comes out of  experience. Strictly numerically speaking, you are
correct. But if you look at recognition accuracy, pacing of speech, and flow of
words through the vocal track, my solution is  gentler on the vocal tract, body
stress (tension anticipating this recognition errors), and cognition (don't need
a spare any mental cycles on  anticipation of failure and how to correct). I can
just say focused on what I'm dictating. Additionally, making corrections of my
style is easier (i.e. you can make the correction) but the form you propose with
Locks (see, this is one of those "I'm going to bust a In your ass" type errors)
cannot be corrected. He can only be deleted and restated.

I apologize for being a "I'm the expert know it all" on this but, I really do
have 15 years experience with these kind of failures and I like to think I know
something about the topic.

>>> Especially when these coding conventions are entirely optional.
>> these conventions are religion for some special if you want to
>> contribute code.
> 
> Does your editor have search and replace? Before you contribute code, do 
> a global replacement of constant_red for RED.

Yes it does and, it you know as well as I do that global search replace blindly
leads to disastrous errors and, increased testing, and the problem doesn't go
away because you always modify your code later.
> 
> 
>> But look at the bigger issue.
> 
> Yes, we get it. It sucks to have a physical disability. The universe 
> isn't arranged to make it easy for those who do, and even systems built 
> by people are only indifferently suitable.

fine. I'll put down that particular baseball bat stop hitting you over the head
with it.  I still think you should try living with naturally speaking for a week
or two.

> 
> So, let's get down to practical matters:
> 
> Do you wish to register a protest against all-caps constants in PEP 8?

only if I had a rational, reasonable alternative. Let me chew on that.
> 
> Do you wish to ask the Python Dev team to rethink their decision?

only when I have rational, reasonable alternatives.
> 
> Do you wish to raise the profile of disabled programmers?

yes. Not exactly sure of the best way but I would like to do that through
providing tools enabling them to participate on equal footing with not yet
disabled programmers.  I really don't like saying "take pity on the poor
programmers with broken hands." I'd rather say "you need talent? Here's a pool
you have previously thrown away but they can now generate code faster than the
keyboard users.

> Do you wish to start a project developing a better, smarter editor, and 
> are looking for volunteers?

yes. This also opens up a great big giant hairball. Specifically, how do you
edit on one machine but do all of your testing and debugging on the second (i.e.
edit on Windows, do everything else on Linux. Unfortunately, I have quite a bit
of scar tissue with this as well and can tell you all about how the different
network file systems fail in special and wonderful ways.

but let's deal with the editor first.

yes, I would like to start a smarter editor project and the only way I could do
it is with volunteers. I would not be able to write code for it until it had
progressed significantly.  What I can do is provide the knowledge of a
first-generation system should look like, evolutionary corrections thereafter. I
can also help with interfacing Python two to speech recognition and creation of
grammars and their code.

I'm a strong believer in recycling existing systems. We might get lucky and make
it better for them to.

if you're willing to help me find volunteers, get this started (I only need some
nudges in the right direction), I gladly accept your help and your knowledge.


From rajat.dudeja at gmail.com  Thu Jul  2 02:50:43 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Wed, 1 Jul 2009 23:50:43 -0700 (PDT)
Subject: Accessing windows structures through ctypes.
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
	<eac94481-c76b-46f8-bac6-48794fc264af@d4g2000yqa.googlegroups.com>
Message-ID: <8c8b5cf2-bc77-4633-96ca-e3b908430492@z14g2000yqa.googlegroups.com>


> > Using ctypes can I access the windows structures like:
>
> > PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> > PEB_LDR_DATA, etc?
>
> ctypes.wintypes lists all of the Windows structures included with the
> module.
>
> You should be able to use ctypes.Structure class to roll your own:

Thanks Alex. As you suggested, I'm trying to implemenet the below
structure, windows PEB, in Python:

typedef struct _PEB {
    BYTE Reserved1[2];
    BYTE BeingDebugged;
    BYTE Reserved2[21];
    PPEB_LDR_DATA LoaderData;
    PRTL_USER_PROCESS_PARAMETERS ProcessParameters;
    BYTE Reserved3[520];
    PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine;
    BYTE Reserved4[136];
    ULONG SessionId;
} PEB;

My equivalent Python structure is:
class PEB(Structure):
    _fields_ = [("Reserved1", wintypes.BYTE * 2),
                ("BeingDebugged", wintypes.BYTE),
                ("Reserved2", wintypes.BYTE * 2),
                ("Reserved3", c_void_p),
                ("Ldr", pointer(PEB_LDR_DATA)),
                ("ProcessParameters", pointer
(RTL_USER_PROCESS_PARAMETERS)),
                ("Reserved4", wintypes.BYTE * 104),
                ("Reserved5", c_void_p),
                (),
                ("Reserved6", wintypes.BYTE),
                ("Reserved7", c_void_p),
                ("SessionId", c_ulong)]

I'm not sure what needs to go in the above empty tuple for
"PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine" (in Original
PEB).

Please suggest.


From sgm at objexx.com  Thu Jul  2 02:54:25 2009
From: sgm at objexx.com (SK)
Date: Wed, 1 Jul 2009 23:54:25 -0700 (PDT)
Subject: multiprocessing and freezing on Windows
Message-ID: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>

Is there a method for freezing a Python 2.6 app using multiprocessing
on Windows using PyInstaller or py2exe that works? It is trying to
call my executable instead of python.exe when the process starts and
passes it --multiprocessing-fork . Adding a freeze_support() to my
main doesn't help. Do I have to bundle all of Python and use
set_executable() to point to the bundled python.exe? I can't find any
workable information on the canonical way to do this.

Thanks!


From clp2 at rebertia.com  Thu Jul  2 03:02:41 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 2 Jul 2009 00:02:41 -0700
Subject: Open Source RSS Reader in Python?
In-Reply-To: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <50697b2c0907020002o16536566h948856375ea3289e@mail.gmail.com>

On Wed, Jul 1, 2009 at 4:18 PM, Alex<alex.lavoro.propio at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?

Straw for GTK/GNOME is written in Python, though it's somewhat inactive.
http://projects.gnome.org/straw/
http://strawreader.wordpress.com/

Cheers,
Chris
-- 
http://blog.rebertia.com


From eckhardt at satorlaser.com  Thu Jul  2 03:11:48 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Thu, 02 Jul 2009 09:11:48 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
Message-ID: <k63uh6-861.ln1@satorlaser.homedns.org>

Hi!

I'm currently converting my bioware to handle Python code and I have
stumbled across a problem...

Simple scenario: I have a handle to a resource. This handle allows me to
manipulate the resource in various ways and it also represents ownership.
Now, when I put this into a class, instances to that class can be shared,
using Python's reference counting. What I'm missing is a way to
automatically release the resource, something which I would do in the
destructor in C++.

Any ideas how to solve this?

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From 4564 at 755189.45  Thu Jul  2 03:42:09 2009
From: 4564 at 755189.45 (Enrico)
Date: Thu, 2 Jul 2009 09:42:09 +0200
Subject: Accessing windows structures through ctypes.
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
	<eac94481-c76b-46f8-bac6-48794fc264af@d4g2000yqa.googlegroups.com>
	<8c8b5cf2-bc77-4633-96ca-e3b908430492@z14g2000yqa.googlegroups.com>
Message-ID: <4a4c650c$0$1115$4fafbaef@reader3.news.tin.it>

"Rajat" <rajat.dudeja at gmail.com> ha scritto nel messaggio
news:8c8b5cf2-bc77-4633-96ca-e3b908430492 at z14g2000yqa.googlegroups.com...
>
> > > Using ctypes can I access the windows structures like:
> >
> > > PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> > > PEB_LDR_DATA, etc?
> >
> > ctypes.wintypes lists all of the Windows structures included with the
> > module.
> >
> > You should be able to use ctypes.Structure class to roll your own:
>
> Thanks Alex. As you suggested, I'm trying to implemenet the below
> structure, windows PEB, in Python:
>
> typedef struct _PEB {
>     BYTE Reserved1[2];
>     BYTE BeingDebugged;
>     BYTE Reserved2[21];
>     PPEB_LDR_DATA LoaderData;
>     PRTL_USER_PROCESS_PARAMETERS ProcessParameters;
>     BYTE Reserved3[520];
>     PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine;
>     BYTE Reserved4[136];
>     ULONG SessionId;
> } PEB;
>
> My equivalent Python structure is:
> class PEB(Structure):
>     _fields_ = [("Reserved1", wintypes.BYTE * 2),
>                 ("BeingDebugged", wintypes.BYTE),
>                 ("Reserved2", wintypes.BYTE * 2),
>                 ("Reserved3", c_void_p),
>                 ("Ldr", pointer(PEB_LDR_DATA)),
>                 ("ProcessParameters", pointer
> (RTL_USER_PROCESS_PARAMETERS)),
>                 ("Reserved4", wintypes.BYTE * 104),
>                 ("Reserved5", c_void_p),
>                 (),
>                 ("Reserved6", wintypes.BYTE),
>                 ("Reserved7", c_void_p),
>                 ("SessionId", c_ulong)]
>
> I'm not sure what needs to go in the above empty tuple for
> "PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine" (in Original
> PEB).
>
> Please suggest.

PostProcessInitRoutine should be a callback function or something similar.
It should be enough to define a type

PostProcessInitRoutine = WINFUNCTYPE(...parameters...)

and use this.

Regards,
Enrico




From Joachim at Strombergson.com  Thu Jul  2 03:57:14 2009
From: Joachim at Strombergson.com (=?UTF-8?B?Sm9hY2hpbSBTdHLDtm1iZXJnc29u?=)
Date: Thu, 02 Jul 2009 09:57:14 +0200
Subject: PEP 376
In-Reply-To: <h2f7jt$j33$1@south.jnrs.ja.net>
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
Message-ID: <4A4C685A.8020300@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

Richard Brodie wrote:
> "Joachim Str?mbergson" <Joachim at Strombergson.com> wrote in message 
> news:mailman.2422.1246418400.8015.python-list at python.org...
> 
>> Even so, choosing md5 in 2009 for something that (hopefully) will be
>> used in years is a bad design decision. It creates a dependency for to
>> an algorithm that all sensible recommendations point you to move away
>> from.
> 
> Why not write the field as algorithm:value?
> 
> e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4
> 
> Installers can fallback to using hashlib.new(), so you can plug in a new
> algorithm without changing the PEP or the installer code. 

+1

Good idea and future proof as well as being simple.

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMaFoACgkQZoPr8HT30QHVxQCfWqKprUaAQxaxTfYJVfIp8+FC
5UIAn2cWNoMe+sdNO4BSZG7e+19qkqvl
=Id7s
-----END PGP SIGNATURE-----


From petshmidt at googlemail.com  Thu Jul  2 04:25:29 2009
From: petshmidt at googlemail.com (Tep)
Date: Thu, 2 Jul 2009 01:25:29 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
Message-ID: <02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>

On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
> someone wrote:
> > Hello,
>
> > how can I replace '?' sign from string? Or do split at that character?
> > Getting unicode error if I try to do it:
>
> > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > 1: ordinal not in range(128)
>
> > Thanks, Pet
>
> > script is # -*- coding: UTF-8 -*-
>
> It sounds like you're mixing bytestrings with Unicode strings. I can't
> be any more helpful because you haven't shown the code.

Oh, I'm sorry. Here it is

def cleanInput(input)
    return input.replace('?', '')


From petshmidt at googlemail.com  Thu Jul  2 04:31:46 2009
From: petshmidt at googlemail.com (Tep)
Date: Thu, 2 Jul 2009 01:31:46 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
	<02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>
Message-ID: <9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>

On 2 Jul., 10:25, Tep <petshm... at googlemail.com> wrote:
> On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > someone wrote:
> > > Hello,
>
> > > how can I replace '?' sign from string? Or do split at that character?
> > > Getting unicode error if I try to do it:
>
> > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > > 1: ordinal not in range(128)
>
> > > Thanks, Pet
>
> > > script is # -*- coding: UTF-8 -*-
>
> > It sounds like you're mixing bytestrings with Unicode strings. I can't
> > be any more helpful because you haven't shown the code.
>
> Oh, I'm sorry. Here it is
>
> def cleanInput(input)
> ? ? return input.replace('?', '')

I also need:

#input is html source code, I have problem with only this character
#input = 'foo ? bar'
#return should be foo
def splitInput(input)
    parts = input.split(' ? ')
    return parts[0]


Thanks!


From Joachim at Strombergson.com  Thu Jul  2 04:32:04 2009
From: Joachim at Strombergson.com (=?UTF-8?B?Sm9hY2hpbSBTdHLDtm1iZXJnc29u?=)
Date: Thu, 02 Jul 2009 10:32:04 +0200
Subject: PEP368 and pixeliterators
Message-ID: <4A4C7084.60000@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

I just read the PEP368 and really liked the proposed idea, sound like a
great battery addition to include in the std lib:

http://www.python.org/dev/peps/pep-0368/

One question/idea though: The proposed iterator will iterate over all
pixels in a line, but only one line. The example code looks like this:

# iterate over an image
for line in rgb_image:
    for pixel in line:
        # swap red and blue, and set green to 0
        pixel.value = pixel.b, 0, pixel.r


But, wouldn't it be more Pythonic and simpler to have an iterator that
iterates over all pixels in an image? Starting with upper left corner
and moving left-right and (line by line) to lower right. This would
change the code above to:

for pixel in rgb_image:
    # swap red and blue, and set green to 0
    pixel.value = pixel.b, 0, pixel.r


The idea I'm having is that fundamentally the image is made up of a 2D
array of pixels, not rows of pixels. And having the iterator focus on
pixels instead make then more sense, no?

Or if possible have two iterators.


Otherwise, big thumbs up for PEP 368 as well as having PEP:s for driving
the language development process in an orderly and well documented way.

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMcIQACgkQZoPr8HT30QFkcgCgzxb9JS2l87B/nkpf05FLDjY5
RPQAni2yPxKjCd4lM/qMBNhjp8HHg/PZ
=9gB/
-----END PGP SIGNATURE-----


From jeremiah.dodds at gmail.com  Thu Jul  2 04:44:44 2009
From: jeremiah.dodds at gmail.com (Jeremiah Dodds)
Date: Thu, 2 Jul 2009 09:44:44 +0100
Subject: Determining if a function is a method of a class within a 
	decorator
In-Reply-To: <4A4AB863.1020205@ilm.com>
References: <mailman.2346.1246323698.8015.python-list@python.org>
	<ac046931-02d7-4067-a9a3-2f2cd9bc3bca@c9g2000yqm.googlegroups.com>
	<4A4AB863.1020205@ilm.com>
Message-ID: <12cbbbfc0907020144s6d7848aci65bab54a726a9f22@mail.gmail.com>

On Wed, Jul 1, 2009 at 2:14 AM, David Hirschfield <davidh at ilm.com> wrote:

>  Unfortunately that still requires two separate decorators, when I was
> hoping there was a way to determine if I was handed a function or method
> from within the same decorator.
>
> Seems like there really isn't, so two decorators is the way to go.
> Thanks,
> -David
>
>
This is a really horrible idea, but it may work:

If you can rely on your code using the word "self", you could use the
inspect module to look at the arguments of the function being decorated, and
dispatch based on that. The idea itself feels extremely dirty though.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/cc45876a/attachment.html>

From __peter__ at web.de  Thu Jul  2 05:11:34 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 11:11:34 +0200
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
	<9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>
Message-ID: <h2htjt$t6e$00$1@news.t-online.com>

Pedram wrote:

> On Jul 1, 10:01 pm, Christian Heimes <li... at cheimes.de> wrote:
>> Pedram schrieb:
>>
>> > Hello community,
>> > I'm reading the CPython interpreter source code,
>> > first, if you have something that I should know for better reading
>> > this source code, I would much appreciate that :)
>> > second, in intobject.c file, I read the following code in
>> > fill_free_list function that I couldn't understand:
>> > <code>while (--q > p)
>> > Py_TYPE(q) = (struct _typeobject *)(q-1);
>> > Py_TYPE(q) = NULL;
>> > </code>
>> > What does it mean?
>>
>> The code is abusing the ob_type member to store a single linked, NULL
>> terminated list of free integer objects. It's a tricky optimization you
>> don't have to understand in order to understand the rest of the code.
>>
>> And no, the code in ctypes.h is totally unrelated to the free list in
>> intobject.c.
>>
>> Christian
> 
> Thanks for reply.
> I totally understood the fill_free_list() function. Thanks.
> But I have problems in understanding the PyInt_FromLong(). Here's the
> code:
> 
> PyObject *
> PyInt_FromLong(long ival)
> {
> register PyIntObject *v;
> #if NSMALLNEGINTS + NSMALLPOSINTS > 0
> if (-NSMALLNEGINTS <= ival && ival < NSMALLPOSINTS) {
> v = small_ints[ival + NSMALLNEGINTS];
> Py_INCREF(v);
> #ifdef COUNT_ALLOCS
> if (ival >= 0)
> quick_int_allocs++;
> else
> quick_neg_int_allocs++;
> #endif
> return (PyObject *) v;
> }
> #endif
> if (free_list == NULL) {
> if ((free_list = fill_free_list()) == NULL)
> return NULL;
> }
> 
> v = free_list; // <-- No problem till here :)
> free_list = (PyIntObject *)Py_TYPE(v);
> PyObject_INIT(v, &PyInt_Type);
> v->ob_ival = ival;
> return (PyObject *) v;
> }
> 
> I understood that small numbers (between -5 and 256) are referenced to
> small_ints list. Others have to store in PyIntBlock, am I right? OK,
> no problem till 'v = free_list;' but can't understand the line
> 'free_list = (PyIntObject *)Py_TYPE(v);' :(. Where free_list
> referenced to? Don't this correct that free_list have to be referenced
> to another free block so next time the function called v store in this
> location?
> Sorry for my bad English. I hope you could understand me :)

Well, if I understand fill_free_list() correctly, you haven't ;) It only 
makes sense together with the allocation code in PyInt_FromLong().

Py_TYPE(v) translates to v->ob_type, and in fill_free_list() that field was 
abused(*) to hold a pointer to the previous item in the array of free 
integers, thereby temporarily turning it into a linked list.

Assuming that free_list pointed to block->objects[10] in the current 
PyIntBlock it will now point to block->objects[9].

When block->objects[0] is reached free_list will be set to NULL as block-
>objects[0]->ob_type was initialized with NULL by the line

Py_TYPE(q) = NULL; /* in fill_free_list() */

The next call of PyInt_FromLong() will then trigger the allocation of a new 
block.

Peter

(*) It may help if you think of the objects array as a

union linked {
    linked *next;
    PyInt_Object obj;
};




From davitadze.tengiz at gmail.com  Thu Jul  2 05:23:00 2009
From: davitadze.tengiz at gmail.com (Tengiz Davitadze)
Date: Thu, 2 Jul 2009 13:23:00 +0400
Subject: Need Help
Message-ID: <2f0bc6280907020223kf2701au81da279a5f8fabaf@mail.gmail.com>

Hello. I can't find a wright mail address. If you can help me I need to get
an information about UNICODE. I am georgian and I need to write programs on
georgian language . If you can transfer this mail or send me a wright mail
about encoding or unicode information.

-- 
Tengiz Davitadze
{
programing Future
}
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/8e46519f/attachment.html>

From sebastian.schabe at gmx.de  Thu Jul  2 05:40:12 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Thu, 02 Jul 2009 11:40:12 +0200
Subject: deleting certain entries in numpy array
In-Reply-To: <mailman.2440.1246489510.8015.python-list@python.org>
References: <4a4b7763$1@news.fhg.de>
	<mailman.2440.1246489510.8015.python-list@python.org>
Message-ID: <4a4c7fd9$1@news.fhg.de>

Robert Kern schrieb:
> First, convert the pos array to integers, and just the columns with 
> indices in them:
> 
>   ipos = pos[:,:2].astype(int)
> 
> Now check the values in the mask corresponding to these positions:
> 
>   mask_values = mask[ipos[:,0], ipos[:,1]]
> 
> Now extract the rows from the original pos array where mask_values is 
> nonzero:
> 
>   result = pos[mask_values != 0]
> 

Great!!! That's the way I wanted.

After reading the numpy reference guide I supposed the delete function 
was not the right way, but that it's all about cerrect indexing. But I 
didn't really know how.

So thanks a lot, also to Ben.

 >
 > You will want to ask numpy questions on the numpy mailing list.
 >
 >   http://www.scipy.org/Mailing_Lists
 >

I ever thought news-groups are the right way for questions like this. 
And the mailing list page just confuses me, but I'm trying to get used 
to it.


Sebastian


From bearophileHUGS at lycos.com  Thu Jul  2 05:50:17 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 2 Jul 2009 02:50:17 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
Message-ID: <6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>

Ulrich Eckhardt:
> a way to automatically release the resource, something
> which I would do in the destructor in C++.

Is this helpful?
http://effbot.org/pyref/with.htm

Bye,
bearophile


From gagsl-py2 at yahoo.com.ar  Thu Jul  2 06:10:17 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 07:10:17 -0300
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
Message-ID: <op.uwfqjfgfx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 01 Jul 2009 12:49:31 -0300, Scott David Daniels  
<Scott.Daniels at acm.org> escribi?:

> Gabriel Genellina wrote:
>> ...
>> def convert(in_queue, out_queue):
>>   while True:
>>     row = in_queue.get()
>>     if row is None: break
>>     # ... convert row
>>     out_queue.put(converted_line)
>
> These loops work well with the two-argument version of iter,
> which is easy to forget, but quite useful to have in your bag
> of tricks:
>
>      def convert(in_queue, out_queue):
>          for row in iter(in_queue.get, None):
>              # ... convert row
>              out_queue.put(converted_line)

Yep, I always forget about that variant of iter() -- very handy!

-- 
Gabriel Genellina



From eckhardt at satorlaser.com  Thu Jul  2 06:12:19 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Thu, 02 Jul 2009 12:12:19 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
Message-ID: <3pduh6-g52.ln1@satorlaser.homedns.org>

Bearophile wrote:
> Ulrich Eckhardt:
>> a way to automatically release the resource, something
>> which I would do in the destructor in C++.
> 
> Is this helpful?
> http://effbot.org/pyref/with.htm

Yes, it aims in the same direction. However, I'm not sure this applies to my
case. The point is that the resource handle is not just used locally in a
restricted scope but it is allocated and stored. The 'with' is something
that makes sense in the context of mutex locking, where you have a
well-defined critical section. What I need is something similar to open(),
which returs a file. When the last reference to that object goes out of
scope, the underlying file object is closed.

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From __peter__ at web.de  Thu Jul  2 06:46:27 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 12:46:27 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
Message-ID: <h2i35q$mp4$01$1@news.t-online.com>

Ulrich Eckhardt wrote:

> Bearophile wrote:
>> Ulrich Eckhardt:
>>> a way to automatically release the resource, something
>>> which I would do in the destructor in C++.
>> 
>> Is this helpful?
>> http://effbot.org/pyref/with.htm
> 
> Yes, it aims in the same direction. However, I'm not sure this applies to
> my case. The point is that the resource handle is not just used locally in
> a restricted scope but it is allocated and stored. The 'with' is something
> that makes sense in the context of mutex locking, where you have a
> well-defined critical section. 

Isn't that exactly what RAII does?

> What I need is something similar to open(),
> which returs a file. When the last reference to that object goes out of
> scope, the underlying file object is closed.

You can go ahead and implement a __del__() method. It will often work in 
CPython, but you get no guarantees, especially when you have reference 
cycles and with other Python implementations that don't use refcounting.

Peter



From pm567426 at gmail.com  Thu Jul  2 06:55:42 2009
From: pm567426 at gmail.com (Pedram)
Date: Thu, 2 Jul 2009 03:55:42 -0700 (PDT)
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
	<9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>
	<h2htjt$t6e$00$1@news.t-online.com>
Message-ID: <7c8e96a1-cbb2-4036-9aa1-1ecdfd84cca8@j32g2000yqh.googlegroups.com>

On Jul 2, 1:11?pm, Peter Otten <__pete... at web.de> wrote:
> Pedram wrote:
> > On Jul 1, 10:01 pm, Christian Heimes <li... at cheimes.de> wrote:
> >> Pedram schrieb:
>
> >> > Hello community,
> >> > I'm reading the CPython interpreter source code,
> >> > first, if you have something that I should know for better reading
> >> > this source code, I would much appreciate that :)
> >> > second, in intobject.c file, I read the following code in
> >> > fill_free_list function that I couldn't understand:
> >> > <code>while (--q > p)
> >> > Py_TYPE(q) = (struct _typeobject *)(q-1);
> >> > Py_TYPE(q) = NULL;
> >> > </code>
> >> > What does it mean?
>
> >> The code is abusing the ob_type member to store a single linked, NULL
> >> terminated list of free integer objects. It's a tricky optimization you
> >> don't have to understand in order to understand the rest of the code.
>
> >> And no, the code in ctypes.h is totally unrelated to the free list in
> >> intobject.c.
>
> >> Christian
>
> > Thanks for reply.
> > I totally understood the fill_free_list() function. Thanks.
> > But I have problems in understanding the PyInt_FromLong(). Here's the
> > code:
>
> > PyObject *
> > PyInt_FromLong(long ival)
> > {
> > register PyIntObject *v;
> > #if NSMALLNEGINTS + NSMALLPOSINTS > 0
> > if (-NSMALLNEGINTS <= ival && ival < NSMALLPOSINTS) {
> > v = small_ints[ival + NSMALLNEGINTS];
> > Py_INCREF(v);
> > #ifdef COUNT_ALLOCS
> > if (ival >= 0)
> > quick_int_allocs++;
> > else
> > quick_neg_int_allocs++;
> > #endif
> > return (PyObject *) v;
> > }
> > #endif
> > if (free_list == NULL) {
> > if ((free_list = fill_free_list()) == NULL)
> > return NULL;
> > }
>
> > v = free_list; // <-- No problem till here :)
> > free_list = (PyIntObject *)Py_TYPE(v);
> > PyObject_INIT(v, &PyInt_Type);
> > v->ob_ival = ival;
> > return (PyObject *) v;
> > }
>
> > I understood that small numbers (between -5 and 256) are referenced to
> > small_ints list. Others have to store in PyIntBlock, am I right? OK,
> > no problem till 'v = free_list;' but can't understand the line
> > 'free_list = (PyIntObject *)Py_TYPE(v);' :(. Where free_list
> > referenced to? Don't this correct that free_list have to be referenced
> > to another free block so next time the function called v store in this
> > location?
> > Sorry for my bad English. I hope you could understand me :)
>
> Well, if I understand fill_free_list() correctly, you haven't ;) It only
> makes sense together with the allocation code in PyInt_FromLong().
>
> Py_TYPE(v) translates to v->ob_type, and in fill_free_list() that field was
> abused(*) to hold a pointer to the previous item in the array of free
> integers, thereby temporarily turning it into a linked list.
>
> Assuming that free_list pointed to block->objects[10] in the current
> PyIntBlock it will now point to block->objects[9].
>
> When block->objects[0] is reached free_list will be set to NULL as block-
>
> >objects[0]->ob_type was initialized with NULL by the line
>
> Py_TYPE(q) = NULL; /* in fill_free_list() */
>
> The next call of PyInt_FromLong() will then trigger the allocation of a new
> block.
>
> Peter
>
> (*) It may help if you think of the objects array as a
>
> union linked {
> ? ? linked *next;
> ? ? PyInt_Object obj;
>
>
>
>
>
> };
>
>

Oh, I got it! What a wonderful implementation! :o
Thanks so much Peter. You made my day :) I didn't read the code
carefully.

>
> ;)
>


From no.email at please.post  Thu Jul  2 07:19:40 2009
From: no.email at please.post (kj)
Date: Thu, 2 Jul 2009 11:19:40 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
Message-ID: <h2i54b$eg3$1@reader1.panix.com>

In <pan.2009.07.02.04.14.35 at REMOVE.THIS.cybersource.com.au> Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:

>On Thu, 02 Jul 2009 03:49:57 +0000, kj wrote:

>> In <Xns9C3BCA27ABC36duncanbooth at 127.0.0.1> Duncan Booth
>> <duncan.booth at invalid.invalid> writes:
>>>So, for example:
>> 
>>>>>> re.compile("c").match("abcdef", 2)
>>><_sre.SRE_Match object at 0x0000000002C09B90>
>>>>>> re.compile("^c").search("abcdef", 2)
>>>>>>
>>>>>>
>> I find this unconvincing; with re.search alone one could simply do:
>> 
>>>>> re.compile("^c").search("abcdef"[2:])
>> <_sre.SRE_Match object at 0x75918>
>> 
>> No need for re.match(), at least as far as your example shows.

>Your source string "abcdef" is tiny. Consider the case where the source 
>string is 4GB of data. You want to duplicate the whole lot, minus two 
>characters. Not so easy now.

I'm sure that it is possible to find cases in which the *current*
implementation of re.search() would be inefficient, but that's
because this implementation is perverse, which, I guess, is ultimately
the point of my original post.  Why privilege the special case of
a start-of-string anchor?  What if you wanted to apply an end-anchored
pattern to some prefix of your 4GB string?  Why not have a special
re method for that?  And another for every possible special case?

If the concern is efficiency for such cases, then simply implement
optional offset and length parameters for re.search(), to specify
any arbitrary substring to apply the search to.  To have a special-case
re.match() method in addition to a general re.search() method is
antithetical to language minimalism, and plain-old bizarre.  Maybe
there's a really good reason for it, but it has not been mentioned
yet.

kj


From nils at ccsg.de  Thu Jul  2 07:30:44 2009
From: nils at ccsg.de (=?ISO-8859-1?Q?Nils_R=FCttershoff?=)
Date: Thu, 02 Jul 2009 13:30:44 +0200
Subject: performance problem with time.strptime()
Message-ID: <4A4C9A64.9030507@ccsg.de>

Hi everyone,

In my free time I translate scripts from open source projects or write
my own, to train my python skills. ATM I convert the aplogmerge.pl from
awstats. It merges multiple apache logfiles and sort the output by the
timestamps of each line.  My first version of this script hasn't a good
performance, so I started profiling. It turned out that the script spend
much time for converting the timestamps of the line into a struct_time
object. Here a code example (Python 2.6.2 on Ubuntu 7.10):

Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

def strptime():
    m = Rec.match(Line)
    if m:
        date_string = m.group(1)
	# date_string example: '02/Jul/2009:01:50:26'
        return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")

with timeit this functions takes approximate 125 sec and 29.004.081
function calls (I've configured timeit with 1.000.000 runs). A look at
the output of cProfile told me that more than the half time is spent in
locale.py:

  1000002   11.712    0.000   19.592    0.000 locale.py:316(normalize)

  1000002    3.639    0.000   23.231    0.000 locale.py:382(_parse_localename)

  1000002    5.162    0.000   30.271    0.000 locale.py:481(getlocale)



I studied the time documentation and thought that I had to set TZ in os
environ:

os.environ['TZ'] = 'Europe/Berlin'

time.set()


but that had no effect. I don't know why time.strptime() looks every
time for my locale. Maybe it's a problem with my OS locale... However.
I've introduced a work around, which works perfectly for my problem. For
time comparison I could use any sort of time representation and so I
convert to epoch:

# needed to translate month str to dig repr

Shortmonth = {'Jan' : '01',

              'Feb' : '02',

              'Mar' : '03',

              'Apr' : '04',

              'May' : '05',

              'Jun' : '06',

              'Jul' : '07',

              'Aug' : '08',

              'Sep' : '09',

              'Oct' : '10',

              'Nov' : '11',

              'Dec' : '12'}

Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")

Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

def epoch():

    m = Rec.match(Line)

    if m:

        result = m.groupdict()

        date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)

        date_tuple = map(int,date_tuple)

        return time.mktime(date_tuple)


with this workaround I had a speed up to 4 times; it tooks only 31 sec
with only 5.000.009 function calls. Maybe this helps some of you, who
had the similar problems with time conversion....

...But one big question remains: Why time.strptime() checks everytime
the locale? had I missed something or could I have a problem with my OS
locale?

With python 3.1 there is no difference, unless that time.strptime() took
approx 12 sec longer... :(

regards, Nils



Here a complete test script:

#!/opt/python/2.6.2/bin/python

import time

import timeit

import cProfile

import re

# needed to tranlate month str to dig repr

Shortmonth = {'Jan' : '01',

              'Feb' : '02',

              'Mar' : '03',

              'Apr' : '04',

              'May' : '05',

              'Jun' : '06',

              'Jul' : '07',

              'Aug' : '08',

              'Sep' : '09',

              'Oct' : '10',

              'Nov' : '11',

              'Dec' : '12'}

Rec1 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")

Rec2 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")

Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

def epoch():

    m = Rec1.match(Line)

    if m:

        result = m.groupdict()

        date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)

        date_tuple = map(int,date_tuple)

        return time.mktime(date_tuple)

def strptime():

    m = Rec2.match(Line)

    if m:

        date_string = m.group(1)

        return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")

if __name__ == "__main__":

    t1 = timeit.Timer("epoch()","from __main__ import epoch")

    t2 = timeit.Timer("strptime()", "from __main__ import strptime")

    cProfile.run("t1.timeit();print")

    print ""

    cProfile.run("t2.timeit();print")




From simon at brunningonline.net  Thu Jul  2 07:34:10 2009
From: simon at brunningonline.net (Simon Brunning)
Date: Thu, 2 Jul 2009 12:34:10 +0100
Subject: Need Help
In-Reply-To: <2f0bc6280907020223kf2701au81da279a5f8fabaf@mail.gmail.com>
References: <2f0bc6280907020223kf2701au81da279a5f8fabaf@mail.gmail.com>
Message-ID: <8c7f10c60907020434u26e0518el6045d23cd89c4bcf@mail.gmail.com>

2009/7/2 Tengiz Davitadze <davitadze.tengiz at gmail.com>:
> Hello. I can't find a wright mail address. If you can help me I need to get
> an information about UNICODE. I am georgian and I need to write programs on
> georgian language . If you can transfer this mail or send me a wright mail
> about encoding or unicode information.

Our chief link is
<http://www.joelonsoftware.com/articles/Unicode.html>.
<http://www.joelonsoftware.com/articles/Unicode.html> and
<http://effbot.org/zone/unicode-objects.htm>. Our two links are
<http://effbot.org/zone/unicode-objects.htm> and
<http://www.joelonsoftware.com/articles/Unicode.html>. And
<http://www.amk.ca/python/howto/unicode>. Our *three* links are
<http://effbot.org/zone/unicode-objects.htm>,
<http://www.joelonsoftware.com/articles/Unicode.html>, and
<http://www.amk.ca/python/howto/unicode>. And
<http://catb.org/esr/faqs/smart-questions.html>. Our *four*...no...
*Amongst* our links.... Amongst our linkry are such elements as
<http://effbot.org/zone/unicode-objects.htm>,
<http://www.joelonsoftware.com/articles/Unicode.html>.... I'll come in
again.

-- 
Cheers,
Simon B.


From Caseyweb at gmail.com  Thu Jul  2 07:45:22 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Thu, 2 Jul 2009 04:45:22 -0700 (PDT)
Subject: performance problem with time.strptime()
References: <mailman.2479.1246534276.8015.python-list@python.org>
Message-ID: <6a2cc3a6-0e5c-4a43-bcf7-416a77253f97@h2g2000yqg.googlegroups.com>

On Jul 2, 7:30?am, Nils R?ttershoff <n... at ccsg.de> wrote:

> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

I'm not sure how much it will help but if you are only using the regex
to get the date/time group element, it might be faster to replace the
regex with:

>>> date_string = Line.split()[3][1:-1]


From ziade.tarek at gmail.com  Thu Jul  2 07:55:30 2009
From: ziade.tarek at gmail.com (=?ISO-8859-1?Q?Tarek_Ziad=E9?=)
Date: Thu, 2 Jul 2009 13:55:30 +0200
Subject: PEP 376
In-Reply-To: <4A4C685A.8020300@Strombergson.com>
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net> <4A4C685A.8020300@Strombergson.com>
Message-ID: <94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>

2009/7/2 Joachim Str?mbergson <Joachim at strombergson.com>:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Aloha!
>
> Richard Brodie wrote:
>> "Joachim Str?mbergson" <Joachim at Strombergson.com> wrote in message
>> news:mailman.2422.1246418400.8015.python-list at python.org...
>>
>>> Even so, choosing md5 in 2009 for something that (hopefully) will be
>>> used in years is a bad design decision. It creates a dependency for to
>>> an algorithm that all sensible recommendations point you to move away
>>> from.
>>
>> Why not write the field as algorithm:value?
>>
>> e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4
>>
>> Installers can fallback to using hashlib.new(), so you can plug in a new
>> algorithm without changing the PEP or the installer code.
>
> +1
>
> Good idea and future proof as well as being simple.

The prefix is a good idea but since it's just a checksum to control
that the file hasn't changed
what's wrong with using a weak hash algorithm like md5 or now sha1 ?

If someone wants to modify a file of a distribution he can recreate
the checksum as well,
the only secured way to prevent that would be to use gpg keys but
isn't that overkill for what we need ?

e.g. making sure a file wasn't modified when distutils uninstalls a
distribution.

Tarek


From hniksic at xemacs.org  Thu Jul  2 07:55:39 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Thu, 02 Jul 2009 13:55:39 +0200
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
Message-ID: <87k52rwb7o.fsf@busola.homelinux.net>

kj <no.email at please.post> writes:

> For a recovering Perl-head like me it is difficult to understand
> why Python's re module offers both match and search.  Why not just
> use search with a beginning-of-string anchor?

I need re.match when parsing the whole string.  In that case I never
want to search through the string, but process the whole string with
some regulat expression, for example when tokenizing.  For example:

    pos = 0
    while pos != len(s):
        match = TOKEN_RE.match(s, pos)
        if match:
            process_token(match)
            pos = match.end()
        else:
            raise ParseError('invalid syntax at position %d' % pos)


From davea at ieee.org  Thu Jul  2 08:05:12 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 02 Jul 2009 08:05:12 -0400
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <k63uh6-861.ln1@satorlaser.homedns.org>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
Message-ID: <4A4CA278.4050604@ieee.org>

Ulrich Eckhardt wrote:
> Hi!
>
> I'm currently converting my bioware to handle Python code and I have
> stumbled across a problem...
>
> Simple scenario: I have a handle to a resource. This handle allows me to
> manipulate the resource in various ways and it also represents ownership.
> Now, when I put this into a class, instances to that class can be shared,
> using Python's reference counting. What I'm missing is a way to
> automatically release the resource, something which I would do in the
> destructor in C++.
>
> Any ideas how to solve this?
>
> Uli
>
>   
As someone else pointed out, 'with' is the first line of defense.  It 
makes the stuff you could already do with try/except/finally much easier 
to get right.

Look also at 'del' a command in the language which explicitly deletes an 
object.

But I'm guessing you want something that automatically deletes objects 
whenever the last reference disappears.  That's an implementation 
detail, not a language guarantee.  In particular CPython does what you 
want, by using reference counting.  That's the only Python I've used, so 
it's only hearsay when I say that other implementations, (maybe Cython 
or Jython) do not all work the same way.

In CPython, any object whose *last* reference goes away, will get 
immediately deleted.  So if you avoid circular references, it should do 
just what you want.  Orphaned circular references are caught by the 
garbage collector, which runs periodically, but is non-deterministic.

Two more caveats.  Exceptions tend to hang onto stuff in their near 
vicinity, and I can't tell you the algorithm for what happens.  But an 
explicit del in the except clause can probably handle that.

Finally, closures can hang onto stuff.  So if you have nested functions, 
or lambda functions, it's possible they're going to keep things longer 
than you realize.





From lists at cheimes.de  Thu Jul  2 08:10:55 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 02 Jul 2009 14:10:55 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <4A4CA278.4050604@ieee.org>
References: <k63uh6-861.ln1@satorlaser.homedns.org> <4A4CA278.4050604@ieee.org>
Message-ID: <h2i84f$v2t$1@ger.gmane.org>

Dave Angel wrote:
> Look also at 'del' a command in the language which explicitly deletes an
> object.

No, you are either explaining it the wrong way or you have been fallen
for a common misinterpretation of the del statement. The del statement
only removes the object from the current scope. This means it decreases
the reference count by one. It does *not* remove the object.

Christian



From Caseyweb at gmail.com  Thu Jul  2 08:17:28 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Thu, 2 Jul 2009 05:17:28 -0700 (PDT)
Subject: PEP368 and pixeliterators
References: <mailman.2475.1246523526.8015.python-list@python.org>
Message-ID: <2aeeb8de-c8f3-4e9d-98f7-d1fa71e1f3a3@d4g2000yqa.googlegroups.com>

On Jul 2, 4:32?am, Joachim Str?mbergson <Joac... at Strombergson.com>
wrote:
> But, wouldn't it be more Pythonic and simpler to have an iterator that
> iterates over all pixels in an image? Starting with upper left corner
> and moving left-right and (line by line) to lower right. This would
> change the code above to:

Unless I'm totally misreading the PEP, the author does provide both
iterators.  Quoting the PEP:

Non-planar images offer the following additional methods:

pixels() -> iterator[pixel]

  Returns an iterator that iterates over all the pixels in the image,
  starting from the top line and scanning each line from left to
right.
  See below for a description of the pixel objects.

__iter__() -> iterator[line]

  Returns an iterator that iterates over all the lines in the image,
  from top to bottom. See below for a description of the line objects.


From __peter__ at web.de  Thu Jul  2 08:54:50 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 14:54:50 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<mailman.2482.1246536325.8015.python-list@python.org>
Message-ID: <h2iamg$qk$02$1@news.t-online.com>

Dave Angel wrote:

> But I'm guessing you want something that automatically deletes objects
> whenever the last reference disappears.  That's an implementation
> detail, not a language guarantee.  In particular CPython does what you
> want, by using reference counting.  That's the only Python I've used, so
> it's only hearsay when I say that other implementations, (maybe Cython
> or Jython) do not all work the same way.

Here are some examples from Kubuntu 9.04's zoo of python implementations:

$ cat del.py
import sys
print sys.version

class A(object):
    def __init__(self, x):
        self.x = x
    def __del__(self):
        print "releasing A(%r)" % self.x

def f():
    a = A("local in function")
f()

a = A("global (one ref)")

c = A("global (cycle)")
c.a = c
del c

b = A("global (no refs)")
del b

print "about to quit"

$ python del.py
2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
[GCC 4.3.3]
releasing A('local in function')
releasing A('global (no refs)')
about to quit
releasing A('global (one ref)')

$ jython del.py
2.2.1
about to quit

$ ipy del.py
2.4.0 (IronPython 1.1.1 (1.1.1) on .NET 2.0.50727.42)
about to quit
releasing A('global (no refs)')
releasing A('global (cycle)')
releasing A('local in function')

Unhandled Exception: System.ArgumentException: I/O operation on closed file
  at IronPython.Runtime.PythonFile.ThrowIfClosed () [0x00000]
  at IronPython.Runtime.PythonFile.Write (System.String s) [0x00000]
$

IronPython sometimes segfaulted.

Peter



From nils at ccsg.de  Thu Jul  2 09:00:11 2009
From: nils at ccsg.de (=?ISO-8859-1?Q?Nils_R=FCttershoff?=)
Date: Thu, 02 Jul 2009 15:00:11 +0200
Subject: performance problem with time.strptime()
In-Reply-To: <6a2cc3a6-0e5c-4a43-bcf7-416a77253f97@h2g2000yqg.googlegroups.com>
References: <mailman.2479.1246534276.8015.python-list@python.org>
	<6a2cc3a6-0e5c-4a43-bcf7-416a77253f97@h2g2000yqg.googlegroups.com>
Message-ID: <4A4CAF5B.2040502@ccsg.de>

Hi Casey
Casey Webster wrote:
> On Jul 2, 7:30 am, Nils R?ttershoff <n... at ccsg.de> wrote:
>
>   
>> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
>> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>>     
>
> I'm not sure how much it will help but if you are only using the regex
> to get the date/time group element, it might be faster to replace the
> regex with:
>
>   
>>>> date_string = Line.split()[3][1:-1]
>>>>         

Indeed this would give a little speed up (by 1000000 iteration approx
3-4 sec). But this would be only a small piece of the cake. Although thx :)

The problem is that time.strptime() consult locale.py for each
iteration. Here the hole cProfile trace:

first with epoch and second with strptime (condensed):

         5000009 function calls in 33.084 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000   33.084   33.084 <string>:1(<module>)
        1    2.417    2.417   33.084   33.084 <timeit-src>:2(inner)
  1000000    9.648    0.000   30.667    0.000 time_test.py:30(epoch)
        1    0.000    0.000   33.084   33.084 timeit.py:177(timeit)
  1000000    3.711    0.000    3.711    0.000 {built-in method groupdict}
  1000000    4.318    0.000    4.318    0.000 {built-in method match}
        1    0.000    0.000    0.000    0.000 {gc.disable}
        1    0.000    0.000    0.000    0.000 {gc.enable}
        1    0.000    0.000    0.000    0.000 {gc.isenabled}
  1000000    7.764    0.000    7.764    0.000 {map}
        1    0.000    0.000    0.000    0.000 {method 'disable' of
'_lsprof.Profiler' objects}
  1000000    5.225    0.000    5.225    0.000 {time.mktime}
        2    0.000    0.000    0.000    0.000 {time.time}

################################################################

         29000009 function calls in 124.449 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000  124.449  124.449 <string>:1(<module>)
        1    2.244    2.244  124.449  124.449 <timeit-src>:2(inner)
  1000000    3.500    0.000   33.559    0.000 _strptime.py:27(_getlang)
  1000000   41.814    0.000  100.754    0.000 _strptime.py:295(_strptime)
  1000000    4.010    0.000  104.764    0.000
_strptime.py:453(_strptime_time)
  1000000   11.647    0.000   19.529    0.000 locale.py:316(normalize)
  1000000    3.638    0.000   23.167    0.000
locale.py:382(_parse_localename)
  1000000    5.120    0.000   30.059    0.000 locale.py:481(getlocale)
  1000000    7.242    0.000  122.205    0.000 time_test.py:37(strptime)
        1    0.000    0.000  124.449  124.449 timeit.py:177(timeit)
  1000000    1.771    0.000    1.771    0.000 {_locale.setlocale}
  1000000    1.735    0.000    1.735    0.000 {built-in method __enter__}
  1000000    1.626    0.000    1.626    0.000 {built-in method end}
  1000000    3.854    0.000    3.854    0.000 {built-in method groupdict}
  1000000    1.646    0.000    1.646    0.000 {built-in method group}
  2000000    8.409    0.000    8.409    0.000 {built-in method match}
        1    0.000    0.000    0.000    0.000 {gc.disable}
        1    0.000    0.000    0.000    0.000 {gc.enable}
        1    0.000    0.000    0.000    0.000 {gc.isenabled}
  2000000    2.942    0.000    2.942    0.000 {len}
        1    0.000    0.000    0.000    0.000 {method 'disable' of
'_lsprof.Profiler' objects}
  3000000    4.552    0.000    4.552    0.000 {method 'get' of 'dict'
objects}
  1000000    2.072    0.000    2.072    0.000 {method 'index' of 'list'
objects}
  1000000    1.517    0.000    1.517    0.000 {method 'iterkeys' of
'dict' objects}
  2000000    3.113    0.000    3.113    0.000 {method 'lower' of 'str'
objects}
  2000000    3.233    0.000    3.233    0.000 {method 'replace' of 'str'
objects}
  2000000    2.953    0.000    2.953    0.000 {method 'toordinal' of
'datetime.date' objects}
  1000000    1.476    0.000    1.476    0.000 {method 'weekday' of
'datetime.date' objects}
  1000000    4.332    0.000  109.097    0.000 {time.strptime}
        2    0.000    0.000    0.000    0.000 {time.time}

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/9b9cdd1f/attachment.html>

From davea at ieee.org  Thu Jul  2 09:00:44 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 02 Jul 2009 09:00:44 -0400
Subject: performance problem with time.strptime()
In-Reply-To: <4A4C9A64.9030507@ccsg.de>
References: <4A4C9A64.9030507@ccsg.de>
Message-ID: <4A4CAF7C.9040800@ieee.org>

Nils R?ttershoff wrote:
> Hi everyone,
>
> In my free time I translate scripts from open source projects or write
> my own, to train my python skills. ATM I convert the aplogmerge.pl from
> awstats. It merges multiple apache logfiles and sort the output by the
> timestamps of each line.  My first version of this script hasn't a good
> performance, so I started profiling. It turned out that the script spend
> much time for converting the timestamps of the line into a struct_time
> object. Here a code example (Python 2.6.2 on Ubuntu 7.10):
>
> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>
> def strptime():
>     m = Rec.match(Line)
>     if m:
>         date_string = m.group(1)
> 	# date_string example: '02/Jul/2009:01:50:26'
>         return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")
>
> with timeit this functions takes approximate 125 sec and 29.004.081
> function calls (I've configured timeit with 1.000.000 runs). A look at
> the output of cProfile told me that more than the half time is spent in
> locale.py:
>
>   1000002   11.712    0.000   19.592    0.000 locale.py:316(normalize)
>
>   1000002    3.639    0.000   23.231    0.000 locale.py:382(_parse_localename)
>
>   1000002    5.162    0.000   30.271    0.000 locale.py:481(getlocale)
>
>
>
> I studied the time documentation and thought that I had to set TZ in os
> environ:
>
> os.environ['TZ'] = 'Europe/Berlin'
>
> time.set()
>
>
> but that had no effect. I don't know why time.strptime() looks every
> time for my locale. Maybe it's a problem with my OS locale... However.
> I've introduced a work around, which works perfectly for my problem. For
> time comparison I could use any sort of time representation and so I
> convert to epoch:
>
> # needed to translate month str to dig repr
>
> Shortmonth = {'Jan' : '01',
>
>               'Feb' : '02',
>
>               'Mar' : '03',
>
>               'Apr' : '04',
>
>               'May' : '05',
>
>               'Jun' : '06',
>
>               'Jul' : '07',
>
>               'Aug' : '08',
>
>               'Sep' : '09',
>
>               'Oct' : '10',
>
>               'Nov' : '11',
>
>               'Dec' : '12'}
>
> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")
>
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>
> def epoch():
>
>     m = Rec.match(Line)
>
>     if m:
>
>         result = m.groupdict()
>
>         date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)
>
>         date_tuple = map(int,date_tuple)
>
>         return time.mktime(date_tuple)
>
>
> with this workaround I had a speed up to 4 times; it tooks only 31 sec
> with only 5.000.009 function calls. Maybe this helps some of you, who
> had the similar problems with time conversion....
>
> ...But one big question remains: Why time.strptime() checks everytime
> the locale? had I missed something or could I have a problem with my OS
> locale?
>
> With python 3.1 there is no difference, unless that time.strptime() took
> approx 12 sec longer... :(
>
> regards, Nils
>
>
>
> Here a complete test script:
>
> #!/opt/python/2.6.2/bin/python
>
> import time
>
> import timeit
>
> import cProfile
>
> import re
>
> # needed to tranlate month str to dig repr
>
> Shortmonth = {'Jan' : '01',
>
>               'Feb' : '02',
>
>               'Mar' : '03',
>
>               'Apr' : '04',
>
>               'May' : '05',
>
>               'Jun' : '06',
>
>               'Jul' : '07',
>
>               'Aug' : '08',
>
>               'Sep' : '09',
>
>               'Oct' : '10',
>
>               'Nov' : '11',
>
>               'Dec' : '12'}
>
> Rec1 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")
>
> Rec2 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
>
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>
> def epoch():
>
>     m = Rec1.match(Line)
>
>     if m:
>
>         result = m.groupdict()
>
>         date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)
>
>         date_tuple = map(int,date_tuple)
>
>         return time.mktime(date_tuple)
>
> def strptime():
>
>     m = Rec2.match(Line)
>
>     if m:
>
>         date_string = m.group(1)
>
>         return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")
>
> if __name__ == "__main__":
>
>     t1 = timeit.Timer("epoch()","from __main__ import epoch")
>
>     t2 = timeit.Timer("strptime()", "from __main__ import strptime")
>
>     cProfile.run("t1.timeit();print")
>
>     print ""
>
>     cProfile.run("t2.timeit();print")
>
>
>
>   
As you say, if you don't actually need the datetime fields, why waste 
time generating them.  You gained a lot more than the time spent in 
locale(), so your algorithm must be faster than the one in strptime().  
That frequently happens when you write a special case for code which is 
otherwise general.

Notice that only a quarter of the time is spent in locale logic (30.271 
secs).  You can't add up the three terms since they're measuring the 
same thing.  Every call to getlocale() results in a call to

_parse_localename(), so the cumulative times of the latter are already included in the cumulative times in getlocale().

Why does it need to call locale() ?  How else is it going to know how to spell the 11th month?





From Joachim at Strombergson.com  Thu Jul  2 09:15:18 2009
From: Joachim at Strombergson.com (=?UTF-8?B?Sm9hY2hpbSBTdHLDtm1iZXJnc29u?=)
Date: Thu, 02 Jul 2009 15:15:18 +0200
Subject: PEP 376
In-Reply-To: <94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
References: <mailman.2410.1246390911.8015.python-list@python.org>	
	<h2ec5l$820$1@lust.ihug.co.nz>	
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>	
	<mailman.2422.1246418400.8015.python-list@python.org>	
	<h2f7jt$j33$1@south.jnrs.ja.net>
	<4A4C685A.8020300@Strombergson.com>
	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
Message-ID: <4A4CB2E6.8010607@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

Tarek Ziad? wrote:
> The prefix is a good idea but since it's just a checksum to control
> that the file hasn't changed
> what's wrong with using a weak hash algorithm like md5 or now sha1 ?

Because it creates a dependency to an old algorithm that should be
deprecated. Also using MD5, even for a thing like this might make people
belive that it is an ok algorithm to use - "Hey, it is used by the
default install in Python, so it must be ok, right?"

If we flip the argument around: Why would you want to use MD5 instead of
SHA-256? For the specific use case the performance will not (should not)
be an issue.

As I wrote a few mails ago, it is time to move forward from MD5 and
designing something in 2009 that will be around for many years that uses
MD5 is (IMHO) a bad design decision.

> If someone wants to modify a file of a distribution he can recreate
> the checksum as well,
> the only secured way to prevent that would be to use gpg keys but
> isn't that overkill for what we need ?

Actually, adding this type of security would IMHO be a good idea.

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMsuYACgkQZoPr8HT30QELagCghfYyHyK5jnkS8DlaQ2ZX4KR8
W+YAniWSvWRvm47/xGu0thTaYioETY94
=2x3X
-----END PGP SIGNATURE-----


From Joachim at Strombergson.com  Thu Jul  2 09:16:36 2009
From: Joachim at Strombergson.com (=?ISO-8859-1?Q?Joachim_Str=F6mbergson?=)
Date: Thu, 02 Jul 2009 15:16:36 +0200
Subject: PEP368 and pixeliterators
In-Reply-To: <2aeeb8de-c8f3-4e9d-98f7-d1fa71e1f3a3@d4g2000yqa.googlegroups.com>
References: <mailman.2475.1246523526.8015.python-list@python.org>
	<2aeeb8de-c8f3-4e9d-98f7-d1fa71e1f3a3@d4g2000yqa.googlegroups.com>
Message-ID: <4A4CB334.9080505@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

Casey Webster wrote:
> Unless I'm totally misreading the PEP, the author does provide both
> iterators.  Quoting the PEP:
> 
> Non-planar images offer the following additional methods:
> 
> pixels() -> iterator[pixel]
> 
>   Returns an iterator that iterates over all the pixels in the image,
>   starting from the top line and scanning each line from left to
> right.
>   See below for a description of the pixel objects.

Ah! I knew there was a reason for me wearing glasses. ;-)

Go PEP368!

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMszQACgkQZoPr8HT30QGmVACfezmlZ+K93exuIEoUDJyzNzgM
3dcAn1x4Ghu9AlMKEme2og4sK4TwhXaR
=bNbl
-----END PGP SIGNATURE-----


From davea at dejaviewphoto.com  Thu Jul  2 09:21:40 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Thu, 02 Jul 2009 09:21:40 -0400
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <h2i84f$v2t$1@ger.gmane.org>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<4A4CA278.4050604@ieee.org> <h2i84f$v2t$1@ger.gmane.org>
Message-ID: <4A4CB464.80607@dejaviewphoto.com>

Christian Heimes wrote:
> Dave Angel wrote:
>   
>> Look also at 'del' a command in the language which explicitly deletes an
>> object.
>>     
>
> No, you are either explaining it the wrong way or you have been fallen
> for a common misinterpretation of the del statement. The del statement
> only removes the object from the current scope. This means it decreases
> the reference count by one. It does *not* remove the object.
>
> Christian
>
>
>   
You're right of course.  What I was trying to say was it deletes the 
reference to the object.  Unlike obj = None, del obj removes the 
reference (attribute) entirely. Although I don't know what it should be 
called if it's a local variable.  Perhaps it "unbinds" the name.

DaveA



From Mariosky at gmail.com  Thu Jul  2 09:27:36 2009
From: Mariosky at gmail.com (Mario Garcia)
Date: Thu, 2 Jul 2009 06:27:36 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<05dde563-a8f1-45d1-8f59-7740c58787ba@e21g2000yqb.googlegroups.com>
Message-ID: <32f177b3-f305-4ff7-be64-ed161eb7c38d@h11g2000yqb.googlegroups.com>



This could be better:

>>> import random
>>> population = range(10)
>>> choice = random.choice(population)
>>> population.remove(choice)
>>> print population
>>> print population
[0, 1, 2, 3, 4, 5, 6, 8, 9]

That was my idea with the previous pop(), remove from the population a
certain number of elements at random.
In the docs pop is defined as:
 Remove and return an arbitrary element from the set.
My mistake: arbitrary is not the same as random :(

Mario




From lie.1296 at gmail.com  Thu Jul  2 09:33:38 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 13:33:38 GMT
Subject: pep 8 constants
In-Reply-To: <mailman.2471.1246516416.8015.python-list@python.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<mailman.2273.1246252100.8015.python-list@python.org>	<a5a4183c-1dd0-40b2-bdf4-5895488c165c@t21g2000yqi.googlegroups.com>	<mailman.2306.1246290580.8015.python-list@python.org>	<025949cb$0$20671$c3e8da3@news.astraweb.com>	<mailman.2352.1246329493.8015.python-list@python.org>	<pan.2009.06.30.05.45.18@REMOVE.THIS.cybersource.com.au>
	<mailman.2471.1246516416.8015.python-list@python.org>
Message-ID: <SG23m.2218$ze1.1019@news-server.bigpond.net.au>

Eric S. Johansson wrote:
> Steven D'Aprano wrote:
>> That assumes that every word is all caps. In practice, for real-life 
>> Python code, I've tripled the vocal load of perhaps one percent of your 
>> utterances, which cuts your productivity by 2%.
>>
>> If you have 10000 words in you per day, and one percent get wrapped with 
>> a leading and trailing "capslock", you have:
>>
>> 9900 regular words plus 100 constants
>>
>> versus
>>
>> 9700 regular words plus 100 constants plus 200 by capslock.
>>
>> Your productivity goes down by 200 words out of 10,000, or two percent.
> 
> oh I wish it was so simple. I would absolutely you if it was that simple the
> real world. Somehow, I fear that you wouldn't understand unless you sat next to
> me and watch me try to write code to  a variety of standards.
> 
> In practice, my experience says that with a really good  speech driven
> environment for programming, IT, vocal load probably by a quarter to a half and
> be more compliant with current fashion for naming.

I've tried (Windows') speech recognition some time before, and I know
it's one heck of a mess trying to type anything with it. I have a fully
working hand, so I don't actually need a voice recognition, but I
remember trying to write a single (not code) paragraph solely by
recognition. It took me over an hour correcting all those mistakes and
it really starts to gets into the nerves after the first sentence. I did
a little victory dance, after doing the first paragraph.

I know they gets better with time as they learn our speech pattern and
we learn how to pronounce the way the voice recognition expects. But one
thing I can't imagine is using voice recognition for writing code
(heck... that'll be a nightmare inside a nightmare)

>>>>> Heck, have you ever noticed how most Python smart editors can't even
>>>>> indent properly according to local contexts. Emacs is the only one and
>>>>> even that one sometimes fails
>>>> I use kwrite for editing, and I can't say I've ever noticed a failure.
>>> okay, it fails from a speech recognition user perspective. Put the
>>> cursor on the line and hit the tab key. Insert spaces/tabs in the line
>>> of text. Not good for speech recognition. If  mess of indentation and
>>> hit the tab key, it doesn't automatically indent to the right location.
>>> I'll be damned if I'm in the sit there speaking
>>> "tabkeytabkeytabkeytabkeytabkey" because the error should take care of
>>> it for me and save my voice. Like I said, Emacs does it correctly and
>>> nobody else does as far as I can tell.
>> I don't understand what you're describing.
>>
>> If you set kwrite to use "Python style" indent mode, then starting a new 
>> line will automatically indent to either the current indent level, or one 
>> extra indent level if the line ends with a colon. You shouldn't need to 
>> indent forward more than one level at a time when writing Python code, 
>> although you will need to dedent multiple levels on occasion.
> 
> I recognize your confusion. It's very common when describing this problem. If I
> had some way of making a movie of what  and describing, obviously be more clear.
> I'll see if I can make a movie with my camera that demonstrates the problem.  It
> probably won't happen fast but, what I tried your editor, it failed   with a
> trivial effort.  I think I just hit the tab key multiple times in different
> places on the line. In all cases it did the wrong thing. For me, the right thing
> is to force the line to the right indentation based on the previous line to
> matter how may times you get the tab key or where you are on that line when you
> hit the tab key. I could be in the middle of the line, the end of line, start a
> line, the start of the string and if I hit a tab key, that line should go to
> exactly the right place stayed there no matter how me more times I typed a tab key.
> 
> But this might be what you're getting confused. What I'm really asking for is
> the ability to say "force indent" and have the line indent exactly correctly
> based on context. It doesn't have to be the tab key. The tab key is the method
> of convenience.

Maybe we need an editor that could sort of understand something like:
"constant red"
and apply the appropriate code-sensitive convention transformation (in
python it'll be RED)
"class foo inheriting object"
and typed "class Foo(object):\n\t"
"indent", "dedent"
put a tab or delete a tab (or softtab)

but for all those, we're going to need a specialized text editor or
perhaps a context-sensitive voice recognition software. The simplest
solution would be a vim plugin or emacs mode that is specially tailored
to recognize these commands and apply the appropriate transformations
depending on the contexts.

>> I've already said it's your right to reject the convention for your own 
>> code. Go right ahead. This is only a problem if you're editing other 
>> people's code which is using uppercase constants.
> 
> exactly. If I'm unable to comply with local conventions, I cannot work within an
> organization and be an active member of the team. This is one example of what I
> mean by unintentional discriminatory effects of a given decision.  rhetorical
> devices aside, I think the right way to deal with accessibility issues and
> decisions leading to discrimination is to make the appropriate tools if possible
> for the individual. But I'm sure that would be a very long discussion we would
> have over a couple of beers.

Personally, I think it'd be very difficult to try to change conventions
that were made for a job that requires so much typing. In programming,
typing is almost a requirement. I'm aware people will still try to
insist on doing things they love the most no matter what happens, but I
still think if the disabled want to program, they're the one that need
to adjust their work flow and definitely with the current voice
recognition technology, they really need better tools.

>> Do you wish to raise the profile of disabled programmers?
> 
> yes. Not exactly sure of the best way but I would like to do that through
> providing tools enabling them to participate on equal footing with not yet
> disabled programmers.  I really don't like saying "take pity on the poor
> programmers with broken hands." I'd rather say "you need talent? Here's a pool
> you have previously thrown away but they can now generate code faster than the
> keyboard users.

Stephen Hawking didn't stop with his experiments when his whole body
can't move. I agree that disabilities shouldn't stop people from
programming, which is mostly the head's job. I think if we can make
voice recognition faster and easier than typing (like in those sci-fi
movies), disabled or not we will all benefit from it. Maybe some day, we
all, disabled or not, might code with voice recognition and keyboard
will be considered obsolete.


From lie.1296 at gmail.com  Thu Jul  2 09:40:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 13:40:49 GMT
Subject: pep 8 constants
In-Reply-To: <mailman.2392.1246375713.8015.python-list@python.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>	<4A48E307.50804@harvee.org>
	<4A49E232.6090101@tim.thechases.com>
	<mailman.2392.1246375713.8015.python-list@python.org>
Message-ID: <BN23m.2219$ze1.1708@news-server.bigpond.net.au>

Eric S. Johansson wrote:

> I've been working with speech recognition for 15 years. I've written something
> on the order of 10,000 lines of Python code both as open source and private
> projects. I've tried it least two dozen editors and they all fail miserably
> because they're focused on keyboard use (but understandable) I get good
> recognition accuracy because I train the system and then I let it train me.
>> For coding, you might want to investigate a tool like Dasher[1] which
>> offers an alternate form of input.  It allows for custom
>> vocabularies/keymaps if you need, as well as more precise specification
>> of a full keyboard (caps vs. mixed-case, specific punctuation
>> characters, etc).  The predictive entry should be smart enough to pick
>> up previously entered constants/terms saving you entry speed.  It can
>> also be driven by a wide variety of pointing devices (mouse, trackball,
>> touchpad, head-tracker, gyro-input, etc).
> 
> I've tried it, it's quite promising but my hands term are sufficiently that I
> can't target accurately. This is a problem for me with mice as well. Maybe these
> tiny little spit dot icons and webpages drive me insane because it takes me two
> or three tries to put the right spot.

You might want to try eye-ball tracking device. Dashers are designed for
that as well. You won't need to use your hand to type with it.


From nils at ccsg.de  Thu Jul  2 09:51:25 2009
From: nils at ccsg.de (=?ISO-8859-1?Q?Nils_R=FCttershoff?=)
Date: Thu, 02 Jul 2009 15:51:25 +0200
Subject: Spam? Re: whizBase vs. Python
In-Reply-To: <0bc58d9a-37cf-4e09-a28f-5edb0489ea30@h8g2000yqm.googlegroups.com>
References: <620ad7d3-6c1a-4869-b844-1951095bb92c@g19g2000yql.googlegroups.com>	<Ms%1m.1712$8r.1372@nlpi064.nbdc.sbc.com>
	<0bc58d9a-37cf-4e09-a28f-5edb0489ea30@h8g2000yqm.googlegroups.com>
Message-ID: <4A4CBB5D.9070104@ccsg.de>

NurAzije wrote:
> On Jun 29, 11:04 am, Tim Harig <user... at ilthio.net> wrote:
>   
>> On 2009-06-29, NurAzije <nuraz... at gmail.com> wrote:
>>
>>     
>>> Hi,
>>> I am working on a study and I need expert opinion, I did not work with
>>> Python before, can anyone help me with a comparison betweenWhizBase
>>> (www.whizbase.com) and Python please.
>>>       
>> Given posts like:http://groups.google.com/group/Server-side-programing/browse_thread/t...
>> is this just thinly veiled spam?  The domain and the posting IP address are
>> both out of Sarajevo, Bosnia.
>>
>> Obviously you alreadly know your product is nothing but a database
>> macro processor.  Python is a dynamic programming language and therefore
>> far more capable.
>>
>> Your product is proprietary with less capability while Python is free and
>> powerful.
>>     
>
> Hi Tim,
> I am not a spammer, WhizBase is from Sarajevo and I am from Sarajevo,
> for that it is interesting for me.
>
> regards,
> Ashraf Gheith
>   
Hi Ashraf,

hm... but it seems you know WhizBase very well, here a blog
(http://whizbase-scripting-language.blogspot.com/) of you with very
detailed information about WhizBase. Why you are asking nearly any
programming list/group about the difference?:

http://www.highdots.com/forums/javascript-discussion-multi-lingual/whizbase-vs-javascript-281242.html
http://groups.google.com/group/alt.comp.lang.learn.c-c++/browse_thread/thread/a7a47adb904319ad
http://groups.google.com/group/comp.lang.lisp/browse_thread/thread/9dfa76ad94d75168/01a999b7b8638621?lnk=raot
http://www.mail-archive.com/dotnetdevelopment at googlegroups.com/msg07381.html

Hm here the main blog:
http://whizbase.blogspot.com/

There is a second contributer Faik Djikic and Whizbase is from a company
called "Djikic Software Development"......

What's the Topic of your study? Whizbase compared to other languages?
Why Whizbase? Is your study public and if so were we could read it? ;)

Regards, Nils
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/6312fbdc/attachment.html>

From jcd at sdf.lonestar.org  Thu Jul  2 10:15:49 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Thu, 02 Jul 2009 10:15:49 -0400
Subject: Idioms and Anti-Idioms Question
In-Reply-To: <h2erl2$h7l$1@lust.ihug.co.nz>
References: <mailman.1932.1245644100.8015.python-list@python.org>
	<H0F%l.20231$y61.5030@news-server.bigpond.net.au>
	<slrnh402pc.deb.peter@box8.pjb.com.au>
	<mailman.2018.1245772229.8015.python-list@python.org>
	<h2erl2$h7l$1@lust.ihug.co.nz>
Message-ID: <1246544149.5775.0.camel@aalcdl07>

On Wed, 2009-07-01 at 17:19 +1200, Lawrence D'Oliveiro wrote:
> In message <mailman.2018.1245772229.8015.python-list at python.org>, J. Cliff 
> Dyer wrote:
> 
> > If the lines got separated, a leading + could disappear into its line
> > without any errors showing up.  A trailing + would raise a syntax error.
> 
> Unless, of course, it was moved onto the previous line as part of whatever 
> caused the separation of the lines. How would you guard against that?
> 

Can you give an example of what you mean?



From gil.shinar at gmail.com  Thu Jul  2 10:17:58 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Thu, 2 Jul 2009 07:17:58 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
	<5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com> 
	<mailman.2442.1246489542.8015.python-list@python.org>
Message-ID: <20e625ef-8fa2-4ed5-9ae4-a5b3fa2b1019@o6g2000yqj.googlegroups.com>

On Jul 2, 1:08?am, s... at pobox.com wrote:
> ? ? Gil> There's no such group as python-sybase :-(
>
> http://sourceforge.net/mailarchive/forum.php?forum_name=python-sybase...
>
> S

Thanks :-)


From gil.shinar at gmail.com  Thu Jul  2 10:19:36 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Thu, 2 Jul 2009 07:19:36 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
	<mailman.2441.1246489542.8015.python-list@python.org>
Message-ID: <c05cc9db-36de-422b-b639-fff9050075a3@h18g2000yqj.googlegroups.com>

On Jul 2, 1:07?am, s... at pobox.com wrote:
> ? ? Gil> Are you saying, that when you trying to connect to a sybase DBS
> ? ? Gil> server and the DBS or the server is down, you get an error after a
> ? ? Gil> few seconds and not after a few minutes?
>
> Yes, though thankfully our server tends to almost always be up.
>
> ? ? Gil> Which python version are you using?
>
> We're still running 2.4.5 at work and have a slightly hacked very old
> version of the python-sybase package (0.36).
>
> --
> Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> ? ? when i wake up with a heart rate below 40, i head right for the espresso
> ? ? machine. -- chaos @ forums.usms.org

That is really strange :-(
I'll ask in the python-sybase group

Thanks


From nobody at nowhere.com  Thu Jul  2 10:23:51 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 02 Jul 2009 15:23:51 +0100
Subject: PEP368 and pixeliterators
References: <mailman.2475.1246523526.8015.python-list@python.org>
Message-ID: <pan.2009.07.02.14.23.50.656000@nowhere.com>

On Thu, 02 Jul 2009 10:32:04 +0200, Joachim Str?mbergson wrote:

> I just read the PEP368 and really liked the proposed idea, sound like a
> great battery addition to include in the std lib:
> 
> http://www.python.org/dev/peps/pep-0368/

Unfortunately, it's too simplistic, meaning that most of the existing
image formats used by the various GUI toolkits (and OpenGL) will need to
be retained.

Obvious omissions include support for arbitrary numbers of bits per
component (e.g. R5G5B5A1), component, pixel and row strides (padding),
mixing packed and planar components (e.g. packed RGB with a separate alpha
plane), and storage orientation (top-to-bottom or bottom-to-top).

Ideally, an Image should be able to use any sane storage format, so that
you don't have to keep converting the Image to an application-specific
format.

NumPy's arrays would probably be a good model here. Essentially, each
component would have a base pointer plus horizontal and vertical strides
measured in bits.

The strides wouldn't necessarily be the same for all components (allowing
for an R8G8B8 plane with a 3-byte stride plus a distinct A8 plane with a
1-byte stride), vertical stride wouldn't necessarily be greater than
horizontal stride (allowing transposition), strides could be negative
(allowing mirroring), and could be less than a byte (allowing e.g. a 1-bpp
alpha channel, planar 4-bpp data, 12-bpp greyscale, etc).

AFAICT, this would allow all common image storage formats to be
represented. The most common exception is 8-bit RGB data using a 6x6x6
colour cube, but that's not common enough to be worth the added complexity.

The interface should also be flexible enough to allow an Image to be a
"proxy" for a non-local image (e.g. one held in video RAM or in the X
server). You wouldn't be able to get a buffer for the image data, but you
should at least be able to obtain the dimensions and format of such
images, and ideally copy the data (or rectangular subregions) to/from a
local image.



From hv at tbz-pariv.de  Thu Jul  2 10:50:34 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Thu, 02 Jul 2009 16:50:34 +0200
Subject: logging of strings with broken encoding
Message-ID: <7b3vpqF20nct6U1@mid.individual.net>

Hi,

I have bug in my code, which results in the same error has this one:

https://bugs.launchpad.net/bzr/+bug/295653
{{{
Traceback (most recent call last):
  File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
    self.stream.write(fs % msg.encode("UTF-8"))
  ..
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8: ordinal not in range(128)
}}}

I run Python 2.6. In SVN the code is the same (StreamHandler ... def emit...):
http://svn.python.org/view/python/branches/release26-maint/Lib/logging/__init__.py?revision=72507&view=markup

I think msg.encode("UTF-8", 'backslashreplace') would be better here.

What do you think?

Should I fill a bugreport?

  Thomas


-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From vertespain at gmail.com  Thu Jul  2 11:09:43 2009
From: vertespain at gmail.com (masher)
Date: Thu, 2 Jul 2009 08:09:43 -0700 (PDT)
Subject: multiprocessing: pool with blocking queue
Message-ID: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>

Hi,

I am trying to implement a multiprocessing pool that assigns tasks
from a blocking queue. My situation is a pretty classic producer/
consumer conundrum, where the producer can produce much faster than
the consumers can consume. The wrinkle in the story is that the
producer produces objects that consume large amounts of memory, so I
would like the queue to block when it reaches, say, twice the number
of tasks as there are processes in the pool, so that I don't devour my
RAM. I have been able to implement this one way, but I am somewhat
displeased with the result. Code speaks louder than words, so here is
a brief example of the technique I am using, followed by an
explanation of why I am unhappy with it:

===
#!/usr/bin/env python3

import time
import random
from multiprocessing import Pool, Queue, M

def procfunc(queue):
    time.sleep(random.random() * 2)
    return queue.get()*2

def printrange(n):
    for i in range(n):
        print("generated " + str(i))
        yield i

if __name__ == "__main__":
    sm = Manager()
    pool = Pool()
    queuelen = len(pool._pool) * 2
    queue = sm.Queue(queuelen)
    for i in printrange(100):
        queue.put(i)
        pool.apply_async(procfunc, (queue,), callback=print)
    pool.close()
    pool.join()
===

The reason I am unhappy with this trick is that if you examine the
source code of pool.py, you will note that the class Pool already uses
an internal queue, "_taskqueue" from which the tasks are assigned to
processes in the pool.

Particularly:
def __init__(self, processes=None, initializer=None, initargs=()):
    self._setup_queues()
    self._taskqueue = queue.Queue()
...snip

It seems to me that if I could only subclass and do
  queuelen = len(pool._pool) * 2
  self._taskqueue = queue.Queue(queuelen)

later in the constructor, once the pool length has been established, I
would have a much more elegant, transparent solution to the problem.

Unfortunately, the design of the Pool class is such that actually
implementing this solution would be very hackish and inelegant. If
only, say, _setup_queues() were called after the _taskqueue
assignment, then I could override it.

My questions, then, is: Is there a more elegant/pythonic way of doing
what I am trying to do with the current Pool class?

If the verdict is no, I'll be happy to file a bug report.


From dns4 at cornell.edu  Thu Jul  2 11:09:58 2009
From: dns4 at cornell.edu (David Smith)
Date: Thu, 02 Jul 2009 11:09:58 -0400
Subject: logging of strings with broken encoding
In-Reply-To: <7b3vpqF20nct6U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <h2iik4$ltq$1@ruby.cit.cornell.edu>

Thomas Guettler wrote:
> Hi,
> 
> I have bug in my code, which results in the same error has this one:
> 
> https://bugs.launchpad.net/bzr/+bug/295653
> {{{
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
>     self.stream.write(fs % msg.encode("UTF-8"))
>   ..
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8: ordinal not in range(128)
> }}}
> 
> I run Python 2.6. In SVN the code is the same (StreamHandler ... def emit...):
> http://svn.python.org/view/python/branches/release26-maint/Lib/logging/__init__.py?revision=72507&view=markup
> 
> I think msg.encode("UTF-8", 'backslashreplace') would be better here.
> 
> What do you think?
> 
> Should I fill a bugreport?
> 
>   Thomas
> 
> 

I think you have to decode it first using the strings original encoding
whether that be cp1252 or mac-roman or any of the other 8-bit encodings.
 Once that's done, you can encode in UTF-8

--David


From __peter__ at web.de  Thu Jul  2 11:16:29 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 17:16:29 +0200
Subject: logging of strings with broken encoding
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <h2ij02$kor$01$1@news.t-online.com>

Thomas Guettler wrote:

> I have bug in my code, which results in the same error has this one:
> 
> https://bugs.launchpad.net/bzr/+bug/295653
> {{{
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
>     self.stream.write(fs % msg.encode("UTF-8"))
>   ..
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8:
> ordinal not in range(128) }}}
> 
> I run Python 2.6. In SVN the code is the same (StreamHandler ... def
> emit...):
> http://svn.python.org/view/python/branches/release26-
maint/Lib/logging/__init__.py?revision=72507&view=markup
> 
> I think msg.encode("UTF-8", 'backslashreplace') would be better here.
> 
> What do you think?

That won't help. It's a *decoding* error. You are feeding it a non-ascii 
byte string.

Peter



From wells at submute.net  Thu Jul  2 11:32:40 2009
From: wells at submute.net (Wells Oliver)
Date: Thu, 2 Jul 2009 10:32:40 -0500
Subject: MySQLdb and ordering of column names in list returned by keys() w/ a 
	DictCursor
Message-ID: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>

Is there some kind of mysterious logic to how the the columns are ordered
when executing the following:

sql = "SELECT player_id, SUM(K) AS K, SUM(IP) AS IP, SUM(ER) AS ER, SUM(HR)
AS HR, SUM(H) AS H, SUM(BB) AS BB, Teams.league FROM Pitching INNER JOIN
Teams ON Pitching.team = Teams.team_id WHERE Date BETWEEN '%s' AND '%s'
GROUP BY player_id" % (start, date)
cursor.execute(sql)

for row in cursor.fetchall():
    print row.keys()

What I get is:

['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']

Neither alphabetical nor the order in which they were specified in the query
nor... any seeming order I can suss out. Any ideas? Thanks!

(cursor being a MySQLdb.cursors.DictCursor object.)

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/4fab3fa9/attachment.html>

From python.list at tim.thechases.com  Thu Jul  2 11:48:18 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 02 Jul 2009 10:48:18 -0500
Subject: MySQLdb and ordering of column names in list returned by keys()
	w/ a    DictCursor
In-Reply-To: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
Message-ID: <4A4CD6C2.2030103@tim.thechases.com>

> sql = "SELECT player_id, SUM(K) AS K, SUM(IP) AS IP, SUM(ER) AS ER, SUM(HR)
> AS HR, SUM(H) AS H, SUM(BB) AS BB, Teams.league FROM Pitching INNER JOIN
> Teams ON Pitching.team = Teams.team_id WHERE Date BETWEEN '%s' AND '%s'
> GROUP BY player_id" % (start, date)
> cursor.execute(sql)
> 
> for row in cursor.fetchall():
>     print row.keys()
> 
> What I get is:
> 
> ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
> 
> Neither alphabetical nor the order in which they were specified in the query
> nor... any seeming order I can suss out. Any ideas? Thanks!
> 
> (cursor being a MySQLdb.cursors.DictCursor object.)

My guess is you're experiencing the fact that dicts are unordered 
by nature which allows it to return in any order it likes 
(usually per the internal representation/storage).

-tkc





From lie.1296 at gmail.com  Thu Jul  2 11:49:46 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 15:49:46 GMT
Subject: logging of strings with broken encoding
In-Reply-To: <7b3vpqF20nct6U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <uG43m.2224$ze1.2217@news-server.bigpond.net.au>

Thomas Guettler wrote:
> Hi,
> 
> I have bug in my code, which results in the same error has this one:
> 
> https://bugs.launchpad.net/bzr/+bug/295653
> {{{
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
>     self.stream.write(fs % msg.encode("UTF-8"))
>   ..
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8: ordinal not in range(128)
> }}}

What's the encoding of self.stream? Is it sys.stdout/sys.stderr or a
file object?


From hv at tbz-pariv.de  Thu Jul  2 11:53:14 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Thu, 02 Jul 2009 17:53:14 +0200
Subject: logging of strings with broken encoding
In-Reply-To: <7b3vpqF20nct6U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <7b43faF21l89hU1@mid.individual.net>

My quick fix is this:

class MyFormatter(logging.Formatter):
    def format(self, record):
        msg=logging.Formatter.format(self, record)
        if isinstance(msg, str):
            msg=msg.decode('utf8', 'replace')
        return msg

But I still think handling of non-ascii byte strings should be better.
A broken logging message is better than none.

And, if there is a UnicodeError, handleError() should not send the message
to sys.stderr, but it should use emit() of the current handler.

In my case sys.stderr gets discarded. Its very hard to debug, if you don't
see any logging messages.

  Thomas

Thomas Guettler schrieb:
> Hi,
> 
> I have bug in my code, which results in the same error has this one:
>  ...

-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From wells at submute.net  Thu Jul  2 11:57:05 2009
From: wells at submute.net (Wells Oliver)
Date: Thu, 2 Jul 2009 10:57:05 -0500
Subject: MySQLdb and ordering of column names in list returned by keys() 
	w/ a DictCursor
In-Reply-To: <4A4CD6C2.2030103@tim.thechases.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
	<4A4CD6C2.2030103@tim.thechases.com>
Message-ID: <3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com>

Will this order at least be the same for that same query every time the
script is executed?

On Thu, Jul 2, 2009 at 10:48 AM, Tim Chase <python.list at tim.thechases.com>wrote:

> sql = "SELECT player_id, SUM(K) AS K, SUM(IP) AS IP, SUM(ER) AS ER, SUM(HR)
>> AS HR, SUM(H) AS H, SUM(BB) AS BB, Teams.league FROM Pitching INNER JOIN
>> Teams ON Pitching.team = Teams.team_id WHERE Date BETWEEN '%s' AND '%s'
>> GROUP BY player_id" % (start, date)
>> cursor.execute(sql)
>>
>> for row in cursor.fetchall():
>>    print row.keys()
>>
>> What I get is:
>>
>> ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
>>
>> Neither alphabetical nor the order in which they were specified in the
>> query
>> nor... any seeming order I can suss out. Any ideas? Thanks!
>>
>> (cursor being a MySQLdb.cursors.DictCursor object.)
>>
>
> My guess is you're experiencing the fact that dicts are unordered by nature
> which allows it to return in any order it likes (usually per the internal
> representation/storage).
>
> -tkc
>
>
>
>


-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/44e67377/attachment.html>

From james at agentultra.com  Thu Jul  2 12:06:58 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 02 Jul 2009 12:06:58 -0400
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
Message-ID: <851vozf4rh.fsf@agentultra.com>

masher <vertespain at gmail.com> writes:

> My questions, then, is: Is there a more elegant/pythonic way of doing
> what I am trying to do with the current Pool class?

Forgive me, I may not fully understand what you are trying to do here
(I've never really used multiprocessing all that much)...

But couldn't you just assign your own Queue object to the Pool instance?


From robert.kern at gmail.com  Thu Jul  2 12:23:40 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 02 Jul 2009 11:23:40 -0500
Subject: deleting certain entries in numpy array
In-Reply-To: <4a4c7fd9$1@news.fhg.de>
References: <4a4b7763$1@news.fhg.de>	<mailman.2440.1246489510.8015.python-list@python.org>
	<4a4c7fd9$1@news.fhg.de>
Message-ID: <h2imud$gf8$1@ger.gmane.org>

On 2009-07-02 04:40, Sebastian Schabe wrote:
> Robert Kern schrieb:

>  > You will want to ask numpy questions on the numpy mailing list.
>  >
>  > http://www.scipy.org/Mailing_Lists
>  >
>
> I ever thought news-groups are the right way for questions like this.
> And the mailing list page just confuses me, but I'm trying to get used
> to it.

You may want to try GMane, then:

   http://dir.gmane.org/gmane.comp.python.numeric.general

It's how I read this list, for instance.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From vertespain at gmail.com  Thu Jul  2 12:25:54 2009
From: vertespain at gmail.com (masher)
Date: Thu, 2 Jul 2009 09:25:54 -0700 (PDT)
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
	<851vozf4rh.fsf@agentultra.com>
Message-ID: <cd3362ac-e189-4dea-93d5-06db3aaafd29@c36g2000yqn.googlegroups.com>

On Jul 2, 12:06?pm, J Kenneth King <ja... at agentultra.com> wrote:
> masher <vertesp... at gmail.com> writes:
> > My questions, then, is: Is there a more elegant/pythonic way of doing
> > what I am trying to do with the current Pool class?
>
> Forgive me, I may not fully understand what you are trying to do here
> (I've never really used multiprocessing all that much)...
>
> But couldn't you just assign your own Queue object to the Pool instance?

That's basically my question. It does not appear as though there is
any straightforward way of doing this because of the design of Pool's
__init__ method, which passes _taskqueue to several functions. Hence,
even if I were to reassign _taskqueue after __init__, that wouldn't
change anything.


From ethan at stoneleaf.us  Thu Jul  2 12:38:56 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 02 Jul 2009 09:38:56 -0700
Subject: regex question on .findall and \b
Message-ID: <4A4CE2A0.5040407@stoneleaf.us>

Greetings!

My closest to successfull attempt:

Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel)]
Type "copyright", "credits" or "license" for more information.

IPython 0.9.1 -- An enhanced Interactive Python.

   In [161]: re.findall('\d+','this is test a3 attempt 79')
   Out[161]: ['3', '79']

What I really want in just the 79, as a3 is not a decimal number, but 
when I add the \b word boundaries I get:

   In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
   Out[162]: []

What am I missing?

~Ethan~


From tim.wintle at teamrubber.com  Thu Jul  2 12:49:48 2009
From: tim.wintle at teamrubber.com (Tim Wintle)
Date: Thu, 02 Jul 2009 17:49:48 +0100
Subject: Dict ordering [was: Re: MySQLdb and ordering of column names in
	list returned by keys() w/ a  DictCursor]
In-Reply-To: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
Message-ID: <1246553388.18497.5.camel@tim-laptop>

On Thu, 2009-07-02 at 10:32 -0500, Wells Oliver wrote:
> for row in cursor.fetchall():
>     print row.keys()
> 
> What I get is:
> 
> ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
> 
> Neither alphabetical nor the order in which they were specified in the
> query nor... any seeming order I can suss out. Any ideas? Thanks!

keys in a dict are not guaranteed to be in any specific order. It's not
specific to the MySQLdb cursor.

IIRC it's related to the hashes of the keys (but obviously not in
strictly increasing order). You definitely shouldn't rely on the
ordering (hence the need for an OrderedDict.

e.g. 

>>> a = ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
>>> for s in a:
...   print hash(s)
... 
-3369365635700083487
8448050754076166
9216055368083080
9344056137084361
9600028874
9216027721
1844482854915224472
8832053061079775



From python.list at tim.thechases.com  Thu Jul  2 12:50:09 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 02 Jul 2009 11:50:09 -0500
Subject: MySQLdb and ordering of column names in list returned by keys()
	w/ a DictCursor
In-Reply-To: <3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>	
	<4A4CD6C2.2030103@tim.thechases.com>
	<3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com>
Message-ID: <4A4CE541.9030308@tim.thechases.com>

> Will this order at least be the same for that same query every time the
> script is executed?

I wouldn't count on it.  The order is only defined for the one 
iteration (result of the keys() call).  If the order matters, I'd 
suggest a double-dispatch with a non-dict (regular/default) query 
result, something like

   header_map = dict(
     (desc[0], i)
     for i,desc in enumerate(cursor.description)
     )
   for row in cursor.fetchall():
     print row[header_map['league']]

If you have a lot of fields, I often use a closure to simplify 
the coding:

   for row in cursor.fetchall():
     item = lambda s: row[headermap[s]]
     print item('league')
     print item('BB')
     print item('player_id')

That way, the row stays in order, if you need it that way:

   league, bb, hr, ip, k, h, id, er = row

-tkc





From stefan_ml at behnel.de  Thu Jul  2 13:01:37 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Thu, 02 Jul 2009 19:01:37 +0200
Subject: logging of strings with broken encoding
In-Reply-To: <7b43faF21l89hU1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
Message-ID: <4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>

Thomas Guettler wrote:
> My quick fix is this:
> 
> class MyFormatter(logging.Formatter):
>     def format(self, record):
>         msg=logging.Formatter.format(self, record)
>         if isinstance(msg, str):
>             msg=msg.decode('utf8', 'replace')
>         return msg
> 
> But I still think handling of non-ascii byte strings should be better.
> A broken logging message is better than none.

Erm, may I note that this is not a problem in the logging library but in
the code that uses it? How should the logging library know what you meant
by passing that byte string in the first place? And where is the difference
between accidentally passing a byte string and accidentally passing another
non-printable object? Handling this "better" may simply hide the bugs in
your code, I don't find that's any "better" at all.

Anyway, this has been fixed in Py3.

Stefan


From ethan at stoneleaf.us  Thu Jul  2 13:12:32 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 02 Jul 2009 10:12:32 -0700
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A4CEA80.4050803@stoneleaf.us>

Ethan Furman wrote:
> Greetings!
> 
> My closest to successfull attempt:
> 
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit 
> (Intel)]
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.9.1 -- An enhanced Interactive Python.
> 
>   In [161]: re.findall('\d+','this is test a3 attempt 79')
>   Out[161]: ['3', '79']
> 
> What I really want in just the 79, as a3 is not a decimal number, but 
> when I add the \b word boundaries I get:
> 
>   In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
>   Out[162]: []
> 
> What am I missing?
> 
> ~Ethan~


ARGH!!

Okay, I need two \\ so I'm not trying to match a backspace.  I knew 
(okay, hoped ;) I would figure it out once I posted the question and 
moved on.

*sheepish grin*



From lie.1296 at gmail.com  Thu Jul  2 13:14:34 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 17:14:34 GMT
Subject: logging of strings with broken encoding
In-Reply-To: <7b43faF21l89hU1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
Message-ID: <_V53m.2227$ze1.167@news-server.bigpond.net.au>

Thomas Guettler wrote:
> My quick fix is this:
> 
> class MyFormatter(logging.Formatter):
>     def format(self, record):
>         msg=logging.Formatter.format(self, record)
>         if isinstance(msg, str):
>             msg=msg.decode('utf8', 'replace')
>         return msg
> 
> But I still think handling of non-ascii byte strings should be better.
> A broken logging message is better than none.
> 

The problem is, python 2.x assumed the default encoding of `ascii`
whenever you don't explicitly mention the encoding, and your code
apparently broke with that assumption. I haven't looked at your code,
but others have suggested that you've fed the logging module with
non-ascii byte strings. The logging module can only work with 1) unicode
string, 2) ascii-encoded byte string

If you want a quick fix, you may be able to get away with repr()-ing
your log texts. A proper fix, however, is to pass a unicode string to
the logging module instead.

>>> logging.warn('?') # or logging.warn('\xd1\x8b')
Traceback (most recent call last):
  File "/usr/lib64/python2.6/logging/__init__.py", line 773, in emit
    stream.write(fs % msg.encode("UTF-8"))
UnicodeDecodeError: 'ascii' codec can't decode byte 0xd1 in position 13:
ordinal not in range(128)
>>> logging.warn(repr('?'))
WARNING:root:'\xd1\x8b'
>>> logging.warn(u'?')
WARNING:root:?


From python.list at tim.thechases.com  Thu Jul  2 13:17:22 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 02 Jul 2009 12:17:22 -0500
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A4CEBA2.9040303@tim.thechases.com>

Ethan Furman wrote:
> Greetings!
> 
> My closest to successfull attempt:
> 
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel)]
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.9.1 -- An enhanced Interactive Python.
> 
>    In [161]: re.findall('\d+','this is test a3 attempt 79')
>    Out[161]: ['3', '79']
> 
> What I really want in just the 79, as a3 is not a decimal number, but 
> when I add the \b word boundaries I get:
> 
>    In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
>    Out[162]: []
> 
> What am I missing?

The sneaky detail that the regexp should be in a raw string 
(always a good practice), not a cooked string:

   r'\b\d+\b'

The "\d" isn't a valid character-expansion, so python leaves it 
alone.  However, I believe the "\b" is a control character, so 
your actual string ends up something like:

   >>> print repr('\b\d+\b')
   '\x08\\d+\x08'
   >>> print repr(r'\b\d+\b')
   '\\b\\d+\\b'

the first of which doesn't match your target string, as you might 
imagine.

-tkc





From lie.1296 at gmail.com  Thu Jul  2 13:18:00 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 17:18:00 GMT
Subject: invoking a method from two superclasses
In-Reply-To: <f656c6a7-46ff-45c4-b7eb-98e1378c7f30@b15g2000yqd.googlegroups.com>
References: <mailman.8861.1246401585.8014.python-list@python.org>
	<mailman.2416.1246408453.8015.python-list@python.org>
	<31fe4bef-6738-4de5-b9bb-c0dc42c695a7@o6g2000yqj.googlegroups.com>
	<f656c6a7-46ff-45c4-b7eb-98e1378c7f30@b15g2000yqd.googlegroups.com>
Message-ID: <cZ53m.2228$ze1.66@news-server.bigpond.net.au>

Carl Banks wrote:
> On Jun 30, 6:23 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
>> On Jun 30, 5:34 pm, Mitchell L Model <MLMLi... at Comcast.net> wrote:
>>
>>> Allow me to add to my previous question that certainly the superclass
>>> methods can be called explicitly without resorting to super(), e.g.:
>>>     class C(A, B):
>>>         def __init__(self):
>>>             A.__init__(self)
>>>             B.__init__(self)
>>> My question is really whether there is any way of getting around the
>>> explicit class names by using super()
>> Yes there is: just make sure that all subclasses also call super.
> 
> And by subclasses I mean base classes, of course.  ugh
> 
> 
> Carl Banks

super() is short for two things:
1) superharmful
2) superuseful


From sjoerd at acm.org  Thu Jul  2 13:18:07 2009
From: sjoerd at acm.org (Sjoerd Mullender)
Date: Thu, 02 Jul 2009 19:18:07 +0200
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A4CEBCF.9010203@acm.org>

On 2009-07-02 18:38, Ethan Furman wrote:
> Greetings!
>
> My closest to successfull attempt:
>
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit
> (Intel)]
> Type "copyright", "credits" or "license" for more information.
>
> IPython 0.9.1 -- An enhanced Interactive Python.
>
> In [161]: re.findall('\d+','this is test a3 attempt 79')
> Out[161]: ['3', '79']
>
> What I really want in just the 79, as a3 is not a decimal number, but
> when I add the \b word boundaries I get:
>
> In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
> Out[162]: []
>
> What am I missing?
>
> ~Ethan~

Try this:
 >>> re.findall(r'\b\d+\b','this is test a3 attempt 79')
['79']

The \b is a backspace, by using raw strings you get an actual backslash 
and b.

-- 
Sjoerd Mullender


From philip at semanchuk.com  Thu Jul  2 13:22:53 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 2 Jul 2009 13:22:53 -0400
Subject: dealloc function in python extend c module
In-Reply-To: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
References: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
Message-ID: <8599A253-D2C9-4EE4-AF4F-AEF658BA2033@semanchuk.com>


On Jul 2, 2009, at 2:11 AM, Shen, Yu-Teh wrote:

> I create my extend type something like http://www.python.org/doc/current/extending/newtypes.html 
> .
> And my type has a member which is a pointer point to my allocate
> memory ( no ref count).
> ex:
> ---------------------------------------------------
> typedef struct {
>    PyObject_HEAD
>    /* Type-specific fields go here. */
>    mytype *p;
> } noddy_NoddyObject;
>
> And i write dealloc function like this:
> ---------------------------------------------------
> static void
> Noddy_dealloc(Noddy* self)
> {
>    delete p;
>    self->ob_type->tp_free((PyObject*)self);
> }
>
> And I found it's strange that it didn't call dealloc when there is no
> reference.
>
> ex:
> a = Noddy()
> b = a
> del a
> del b
> # i think there is no ref to the object, and it should call dealloc
> but it didn't call!!!
>
> could anyone tell me what happened?


Hi Shen,
I'm no expert on Python memory management, but since no once else has  
answered your question I'll tell you what I *think* is happening.

Python doesn't delete objects as soon as they're dereferenced. It  
merely marks them as safe for garbage collection (GC). If GC never  
happens (and it might not in a small test program), your dealloc  
function won't run.

Now some more knowledgeable person will probably correct me. =)

You can control the garbage collector manually with Python's gc  
module. You will probably never want to control the garbage collector  
manually in ordinary programs, but it can be useful for testing.


Hope this helps
Philip



From sajmikins at gmail.com  Thu Jul  2 13:23:55 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 10:23:55 -0700 (PDT)
Subject: question of style
Message-ID: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>

Hey I was hoping to get your opinions on a sort of minor stylistic
point.
These two snippets of code are functionally identical. Which would you
use and why?
The first one is easier [for me anyway] to read and understand, but
slightly less efficient, while the second is [marginally] harder to
follow but more efficient.

## First snippet

if self.higher is self.lower is None: return
if self.lower is None: return self.higher
if self.higher is None: return self.lower

## Second snippet

if self.higher is None:
    if self.lower is None:
        return
    return self.lower
if self.lower is None:
    return self.higher

What do you think?

(One minor point: in the first snippet, the "is None" in the first
line is superfluous in the context in which it will be used, the only
time "self.lower is self.higher" will be true is when they are both
None.)


From chambon.pascal at gmail.com  Thu Jul  2 13:34:00 2009
From: chambon.pascal at gmail.com (Pascal Chambon)
Date: Thu, 02 Jul 2009 19:34:00 +0200
Subject: Direct interaction with subprocess - the curse of blocking I/O
In-Reply-To: <pan.2009.06.29.20.45.06.312000@nowhere.com>
References: <mailman.2320.1246302955.8015.python-list@python.org>
	<pan.2009.06.29.20.45.06.312000@nowhere.com>
Message-ID: <4A4CEF88.80201@gmail.com>

Thank you all for the comments

>you might want something like Expect.

Yes "Expect" deals with such things, unfortunately it's posix only (due to the PTY module requirement...); whereas I'd like to find generic ways (i.e at least windows/linux/mac recipes)

> The latter is inherently tricky (which is why C's popen() lets you connect
> to stdin or stdout but not both). You have to use either multiple threads,
> select/poll, or non-blocking I/O.
>
> If the child's output is to the console, it should presumably be the
> former, i.e. piping stdin but allowing the child to inherit stdout, in
> which case, where's the problem? Or are you piping its stdout via Python
> for the hell of it
It's well a too-way piping that I'd like to get ; but actually, even  a 
single-way piping is error-prone : if I try to send data to the child's 
stdin, and this child never wants to receive that data (for whatever 
reason), the parent thread will be forever stuck.
I can use multiple threads, but it doesn't fully solve the problem, 
because having even a single thread stuck might prevent the process from 
terminating, on some operating systems... I'd need a way to deblock I/O 
blocking threads (but even closing the pipe isn't sure to do it properly 
- the closing might be delayed by the I/O operations wating).


 >I would guess the architectural differences are so great that an attempt
 >to "do something simple" is going to involve architecture-specific code.
 >and I personally wouldn't have it any other way.  Simulating a shell
 >with hooks on its I/O should be so complicated that a "script kiddie"
 >has trouble writing a Trojan.

I'm not sure I understand the security hole there - if a script kiddie 
manages to make you execute his program, he doesn't need complex I/O 
redirections to harm you, simply destroying files randomly on your hard 
drive should fit his needs shouldn't it. :?


> > I met the issue : select() works only on windows ...
>   

>No it doesn't. It works only on sockets on Windows, on Unix/Linux it works 
>with all file descriptors <http://docs.python.org/library/select.html>.


Indeed, I mixed up my words there... >_<


 >If you are willing to have a wxPython dependency, wx.Execute handles 
non-blocking i/o with processes on all supported platforms more 
discussion of python's blocking i/o issues here:
 >  
http://groups.google.com/group/comp.lang.python/browse_thread/thread/a037349e18f99630/60886b8beb55cfbc?q=#60886b8beb55cfbc

Very interesting link, that's exactly the problem... and it seems no 
obvious solution comes out of it, except, of course, going down to the 
OS' internals...
File support is really weak in python I feel (stdio is a little 
outdated...), it'd need a complete blocking/non-blocking, 
locking/non-locking stream API straight in the stdlib...
I'm already working on locking classes, I'll explore the opportunity for 
a higher level "file" object too whenever possible (a new filesystem api 
is in progress here at europython2009, it might be the occasion).


regards,
Pascal



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/7d97340c/attachment.html>

From lie.1296 at gmail.com  Thu Jul  2 13:37:01 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 17:37:01 GMT
Subject: PEP 376
In-Reply-To: <mailman.2489.1246540523.8015.python-list@python.org>
References: <mailman.2410.1246390911.8015.python-list@python.org>		<h2ec5l$820$1@lust.ihug.co.nz>		<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>		<mailman.2422.1246418400.8015.python-list@python.org>		<h2f7jt$j33$1@south.jnrs.ja.net>	<4A4C685A.8020300@Strombergson.com>	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
Message-ID: <1f63m.2229$ze1.1410@news-server.bigpond.net.au>

Joachim Str?mbergson wrote:
> Aloha!
> 
> Tarek Ziad? wrote:
>> The prefix is a good idea but since it's just a checksum to control
>> that the file hasn't changed
>> what's wrong with using a weak hash algorithm like md5 or now sha1 ?
> 
> Because it creates a dependency to an old algorithm that should be
> deprecated. Also using MD5, even for a thing like this might make people
> belive that it is an ok algorithm to use - "Hey, it is used by the
> default install in Python, so it must be ok, right?"
> 
> If we flip the argument around: Why would you want to use MD5 instead of
> SHA-256? For the specific use case the performance will not (should not)
> be an issue.
> 
> As I wrote a few mails ago, it is time to move forward from MD5 and
> designing something in 2009 that will be around for many years that uses
> MD5 is (IMHO) a bad design decision.
> 
>> If someone wants to modify a file of a distribution he can recreate
>> the checksum as well,
>> the only secured way to prevent that would be to use gpg keys but
>> isn't that overkill for what we need ?
> 
> Actually, adding this type of security would IMHO be a good idea.
> 

Now, are we actually talking about security or checksum?

It has been known for years that MD5 is weak, weak, weak. Not just in
the recent years. But it doesn't matter since MD5 was never designed for
security, MD5 was designed to protect against random bits corruption. If
you want security, look at least to GPG. For data protection against
intentional, malicious forging, definitely MD5 is the wrong choice. But
when you just want a simple checksum to ensure that a faulty router
somewhere in the internet backbone doesn't destroying your data, MD5 is
a fine algorithm.


From duncan.booth at invalid.invalid  Thu Jul  2 13:44:34 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 2 Jul 2009 17:44:34 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <Xns9C3CBEAA880F8duncanbooth@127.0.0.1>

Simon Forman <sajmikins at gmail.com> wrote:

> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
> 
> ## First snippet
> 
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
> 
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
> 
> What do you think?
> 
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)
> 

I'd write the first one as:

    	if self.lower is None:
    	    	return self.higher
    	if self.higher is None:
    	    return self.lower

because the entire first 'if' statement is redundant.

As a matter of style however I wouldn't use the shorthand to run two 'is' 
comparisons together, I'd write that out in full if it was actually needed 
here.

Likewise in the second one:

    if self.lower is None:
        return
    return self.lower

is obviously the same as:

    	return self.lower

so apart from reversing the order of the comparisons once you've dropped 
the redundant test it is the same as the first one.


From petr.messner at gmail.com  Thu Jul  2 13:48:28 2009
From: petr.messner at gmail.com (Petr Messner)
Date: Thu, 2 Jul 2009 19:48:28 +0200
Subject: MySQLdb and ordering of column names in list returned by keys() 
	w/ a DictCursor
In-Reply-To: <4A4CE541.9030308@tim.thechases.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com> 
	<4A4CD6C2.2030103@tim.thechases.com>
	<3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com> 
	<4A4CE541.9030308@tim.thechases.com>
Message-ID: <67c97cd90907021048u650ae97dhb6da2f34fabd971b@mail.gmail.com>

2009/7/2 Tim Chase <python.list at tim.thechases.com>:
>> Will this order at least be the same for that same query every time the
>> script is executed?
>
> I wouldn't count on it.  The order is only defined for the one iteration
> (result of the keys() call).  If the order matters, I'd suggest a
> double-dispatch with a non-dict (regular/default) query result, something
...

Dictionaries are usually designed to have the best performance when
accessing certain key, so it is not expected that dictionary items
will be in any particular order; this applies not only for Python. But
(for Python dict) you can be sure that results of items(), keys(),
values(), iteritems(), iterkeys(), and itervalues() will correspond if
called with no intervening modifications to the dictionary.

If such a functionality is needed, there is a collections.OrderedDict
that was introduced in Python 3.1; there is also an implementation for
Python 2.4 or later: http://code.activestate.com/recipes/576693/ (this
links is from "What?s New In Python 3.1")

PM


From cbc at unc.edu  Thu Jul  2 13:52:48 2009
From: cbc at unc.edu (Chris Calloway)
Date: Thu, 02 Jul 2009 13:52:48 -0400
Subject: Deadline for Toronto PyCamp Registraiton Appoaching
Message-ID: <4A4CF3F0.4020304@unc.edu>

Tomorrow (July 3) by midnight will be the last opportunity for Toronto 
PyCamp registration before the late registration period ending July 10.

PyCamp is the original Python BootCamp developed by a user group for
user groups. This year PyCamp is July 13-17 at the University of
Toronto, sponsored by the Department of Physics and Scryent. For
beginners, PyCamp makes you productive so you can get your work done
quickly. PyCamp emphasizes the features which make Python a simpler and
more efficient language. Following along by example speeds your learning
process in a modern high-tech classroom. Become a self-sufficient Python
developer in just five days at PyCamp!

http://pycamp.org

-- 
Sincerely,

Chris Calloway
http://www.secoora.org
office: 332 Chapman Hall   phone: (919) 599-3530
mail: Campus Box #3300, UNC-CH, Chapel Hill, NC 27599





From cbc at unc.edu  Thu Jul  2 13:52:48 2009
From: cbc at unc.edu (Chris Calloway)
Date: Thu, 02 Jul 2009 13:52:48 -0400
Subject: Deadline for Toronto PyCamp Registraiton Appoaching
Message-ID: <4A4CF3F0.4020304@unc.edu>

Tomorrow (July 3) by midnight will be the last opportunity for Toronto 
PyCamp registration before the late registration period ending July 10.

PyCamp is the original Python BootCamp developed by a user group for
user groups. This year PyCamp is July 13-17 at the University of
Toronto, sponsored by the Department of Physics and Scryent. For
beginners, PyCamp makes you productive so you can get your work done
quickly. PyCamp emphasizes the features which make Python a simpler and
more efficient language. Following along by example speeds your learning
process in a modern high-tech classroom. Become a self-sufficient Python
developer in just five days at PyCamp!

http://pycamp.org

-- 
Sincerely,

Chris Calloway
http://www.secoora.org
office: 332 Chapman Hall   phone: (919) 599-3530
mail: Campus Box #3300, UNC-CH, Chapel Hill, NC 27599



-- 
http://mail.python.org/mailman/listinfo/python-announce-list

        Support the Python Software Foundation:
        http://www.python.org/psf/donations/
.


From hobesh at gmail.com  Thu Jul  2 13:56:10 2009
From: hobesh at gmail.com (Zach Hobesh)
Date: Thu, 2 Jul 2009 10:56:10 -0700
Subject: Config files with different types
Message-ID: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>

Hi all,

I've written a function that reads a specifically formatted text file
and spits out a dictionary. ?Here's an example:

config.txt:

Destination = C:/Destination
Overwrite = True


Here's my function that takes 1 argument (text file)

the_file = open(textfile,'r')
linelist = the_file.read().split('\n')
the_file.close()
configs = {}
for line in linelist:
       try:
              key,value = line.split('=')
              key.strip()
              value.strip()
              key.lower()
              value.lower()
              configs[key] = value

       except ValueError:
              break

so I call this on my config file, and then I can refer back to any
config in my script like this:

shutil.move(your_file,configs['destination'])

which I like because it's very clear and readable.

So this works great for simple text config files.  Here's how I want
to improve it:

I want to be able to look at the value and determine what type it
SHOULD be.  Right now, configs['overwrite'] = 'true' (a string) when
it might be more useful as a boolean.  Is there a quick way to do
this?  I'd also like to able to read '1' as an in, '1.0' as a float,
etc...

I remember once I saw a script that took a string and tried int(),
float() wrapped in a try except, but I was wondering if there was a
more direct way.

Thanks in advance,

Zach


From db3l.net at gmail.com  Thu Jul  2 13:58:24 2009
From: db3l.net at gmail.com (David Bolen)
Date: Thu, 02 Jul 2009 13:58:24 -0400
Subject: Suppressing Implicit Chained Exceptions (Python 3.0)
References: <mailman.2447.1246492174.8015.python-list@python.org>
Message-ID: <m23a9fezlr.fsf@valheru.db3l.homeip.net>

"andrew cooke" <andrew at acooke.org> writes:

> However, when printed via format_exc(), this new exception still has the
> old exception attached via the mechanism described at
> http://www.python.org/dev/peps/pep-3134/ (this is Python 3.0).

If you're in control of the format_exc() call, I think the new chain
keyword parameter can disable this and restore the old behavior.

If you're not in control of the traceback display, I'm not sure there's
an easy way to prevent it, given that displaying chained exceptions is
the default mode.

-- David


From sajmikins at gmail.com  Thu Jul  2 13:58:56 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 10:58:56 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
Message-ID: <e3e2df13-d0f5-4e79-a55c-cfd52b2997f8@h2g2000yqg.googlegroups.com>

On Jul 2, 1:44?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> wrote:
> > Hey I was hoping to get your opinions on a sort of minor stylistic
> > point.
> > These two snippets of code are functionally identical. Which would you
> > use and why?
> > The first one is easier [for me anyway] to read and understand, but
> > slightly less efficient, while the second is [marginally] harder to
> > follow but more efficient.
>
> > ## First snippet
>
> > if self.higher is self.lower is None: return
> > if self.lower is None: return self.higher
> > if self.higher is None: return self.lower
>
> > ## Second snippet
>
> > if self.higher is None:
> > ? ? if self.lower is None:
> > ? ? ? ? return
> > ? ? return self.lower
> > if self.lower is None:
> > ? ? return self.higher
>
> > What do you think?
>
> > (One minor point: in the first snippet, the "is None" in the first
> > line is superfluous in the context in which it will be used, the only
> > time "self.lower is self.higher" will be true is when they are both
> > None.)
>
> I'd write the first one as:
>
> ? ? ? ? if self.lower is None:
> ? ? ? ? ? ? ? ? return self.higher
> ? ? ? ? if self.higher is None:
> ? ? ? ? ? ? return self.lower
>
> because the entire first 'if' statement is redundant.
>
> As a matter of style however I wouldn't use the shorthand to run two 'is'
> comparisons together, I'd write that out in full if it was actually needed
> here.
>
> Likewise in the second one:
>
> ? ? if self.lower is None:
> ? ? ? ? return
> ? ? return self.lower
>
> is obviously the same as:
>
> ? ? ? ? return self.lower
>
> so apart from reversing the order of the comparisons once you've dropped
> the redundant test it is the same as the first one.

Wow. The equivalence in the second bit is obvious enough-- in
hindsight :] but I totally missed the redundancy in the first bit. I
must be getting old.

Thank you very much.


From charles at declareSub.com  Thu Jul  2 14:00:51 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Thu, 2 Jul 2009 14:00:51 -0400
Subject: PEP 376
In-Reply-To: <1f63m.2229$ze1.1410@news-server.bigpond.net.au>
References: <mailman.2410.1246390911.8015.python-list@python.org>		<h2ec5l$820$1@lust.ihug.co.nz>		<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>		<mailman.2422.1246418400.8015.python-list@python.org>		<h2f7jt$j33$1@south.jnrs.ja.net>	<4A4C685A.8020300@Strombergson.com>	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
	<1f63m.2229$ze1.1410@news-server.bigpond.net.au>
Message-ID: <EF743CC8-5AFE-47F5-97A9-AF993BD4B6C7@declareSub.com>


On Jul 2, 2009, at 1:37 PM, Lie Ryan wrote:

> Joachim Str?mbergson wrote:
>> Aloha!
>>
>> Tarek Ziad? wrote:
>>> The prefix is a good idea but since it's just a checksum to control
>>> that the file hasn't changed
>>> what's wrong with using a weak hash algorithm like md5 or now sha1 ?
>>
>> Because it creates a dependency to an old algorithm that should be
>> deprecated. Also using MD5, even for a thing like this might make  
>> people
>> belive that it is an ok algorithm to use - "Hey, it is used by the
>> default install in Python, so it must be ok, right?"
>>
>> If we flip the argument around: Why would you want to use MD5  
>> instead of
>> SHA-256? For the specific use case the performance will not (should  
>> not)
>> be an issue.
>>
>> As I wrote a few mails ago, it is time to move forward from MD5 and
>> designing something in 2009 that will be around for many years that  
>> uses
>> MD5 is (IMHO) a bad design decision.
>>
>>> If someone wants to modify a file of a distribution he can recreate
>>> the checksum as well,
>>> the only secured way to prevent that would be to use gpg keys but
>>> isn't that overkill for what we need ?
>>
>> Actually, adding this type of security would IMHO be a good idea.
>>
>
> Now, are we actually talking about security or checksum?
>
> It has been known for years that MD5 is weak, weak, weak. Not just in
> the recent years. But it doesn't matter since MD5 was never designed  
> for
> security, MD5 was designed to protect against random bits  
> corruption. If
> you want security, look at least to GPG. For data protection against
> intentional, malicious forging, definitely MD5 is the wrong choice.  
> But
> when you just want a simple checksum to ensure that a faulty router
> somewhere in the internet backbone doesn't destroying your data, MD5  
> is
> a fine algorithm.
> -- 

On the contrary, MD5 was intended to be a cryptographic hash function,  
not a checksum.

Charles Yeomans





From python at mrabarnett.plus.com  Thu Jul  2 14:12:07 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 19:12:07 +0100
Subject: Config files with different types
In-Reply-To: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
References: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
Message-ID: <4A4CF877.6030906@mrabarnett.plus.com>

Zach Hobesh wrote:
> Hi all,
> 
> I've written a function that reads a specifically formatted text file
> and spits out a dictionary.  Here's an example:
> 
> config.txt:
> 
> Destination = C:/Destination
> Overwrite = True
> 
> 
> Here's my function that takes 1 argument (text file)
> 
> the_file = open(textfile,'r')
> linelist = the_file.read().split('\n')

You could use .splitlines() or iterate over the file itself.

> the_file.close()
> configs = {}
> for line in linelist:
>        try:
>               key,value = line.split('=')
>               key.strip()
>               value.strip()
>               key.lower()
>               value.lower()

Strings are immutable. These methods don't modify the strings, but
_return_ the result.

>               configs[key] = value
> 
>        except ValueError:
>               break
> 
'break' will leave the loop. Is this intentional?

> so I call this on my config file, and then I can refer back to any
> config in my script like this:
> 
> shutil.move(your_file,configs['destination'])
> 
> which I like because it's very clear and readable.
> 
> So this works great for simple text config files.  Here's how I want
> to improve it:
> 
> I want to be able to look at the value and determine what type it
> SHOULD be.  Right now, configs['overwrite'] = 'true' (a string) when
> it might be more useful as a boolean.  Is there a quick way to do
> this?  I'd also like to able to read '1' as an in, '1.0' as a float,
> etc...
> 
> I remember once I saw a script that took a string and tried int(),
> float() wrapped in a try except, but I was wondering if there was a
> more direct way.
> 
The way you saw was the safe, and recommended, way.

When checking for Boolean you might want to ignore the case; something
like:

bool_dict = {"false": False, "true": True}
...
try:
     value = bool_dict[value.strip().lower()]
except ValueError:
     # Not a Boolean.
     ...


From kee at kagi.com  Thu Jul  2 14:12:29 2009
From: kee at kagi.com (Kee Nethery)
Date: Thu, 2 Jul 2009 11:12:29 -0700
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <A229B59E-2428-449C-A182-C93E7EB732BB@kagi.com>

the fact that you felt compelled to explain the "one minor point" in  
the first snippet tells me that the second snippet does not need that  
explanation and will be easier for someone (like you for example) to  
maintain in the future.
Second snippet would be my choice.
Kee Nethery

On Jul 2, 2009, at 10:23 AM, Simon Forman wrote:

> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
>
> ## First snippet
>
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
>
> ## Second snippet
>
> if self.higher is None:
>    if self.lower is None:
>        return
>    return self.lower
> if self.lower is None:
>    return self.higher
>
> What do you think?
>
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)
> -- 
> http://mail.python.org/mailman/listinfo/python-list




-------------------------------------------------
I check email roughly 2 to 3 times per business day.
Kagi main office: +1 (510) 550-1336




From pavlovevidence at gmail.com  Thu Jul  2 14:36:38 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 2 Jul 2009 11:36:38 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
Message-ID: <6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>

On Jul 2, 3:12?am, Ulrich Eckhardt <eckha... at satorlaser.com> wrote:
> Bearophile wrote:
> > Ulrich Eckhardt:
> >> a way to automatically release the resource, something
> >> which I would do in the destructor in C++.
>
> > Is this helpful?
> >http://effbot.org/pyref/with.htm
>
> Yes, it aims in the same direction. However, I'm not sure this applies to my
> case. The point is that the resource handle is not just used locally in a
> restricted scope but it is allocated and stored. The 'with' is something
> that makes sense in the context of mutex locking, where you have a
> well-defined critical section. What I need is something similar to open(),
> which returs a file. When the last reference to that object goes out of
> scope, the underlying file object is closed.

On CPython you can do it with a __del__ attribute.

Warning: objects with a __del__ attribute prevent reference cycle
detection, which can potentially lead to memory (and resource) leaks.
So you must be careful to avoid creating reference loops with that
object.

Note that file objects have a close method; you can explicitly close
it at any time.  Your object should follow that example, and define a
close (or release, or whatever) method.  I'd recommend making an
effort to call it and to rely on __del__ as little as possible.


Carl Banks


From nobody at nowhere.com  Thu Jul  2 14:41:54 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 02 Jul 2009 19:41:54 +0100
Subject: regex question on .findall and \b
References: <mailman.2500.1246554153.8015.python-list@python.org>
Message-ID: <pan.2009.07.02.18.41.54.281000@nowhere.com>

On Thu, 02 Jul 2009 09:38:56 -0700, Ethan Furman wrote:

> Greetings!
> 
> My closest to successfull attempt:
> 
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel)]
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.9.1 -- An enhanced Interactive Python.
> 
>    In [161]: re.findall('\d+','this is test a3 attempt 79')
>    Out[161]: ['3', '79']
> 
> What I really want in just the 79, as a3 is not a decimal number, but 
> when I add the \b word boundaries I get:
> 
>    In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
>    Out[162]: []
> 
> What am I missing?

You need to use a raw string (r'...') to prevent \b from being interpreted
as a backspace:

	re.findall(r'\b\d+\b','this is test a3 attempt 79')

\d isn't a recognised escape sequence, so it doesn't get interpreted:

	> print '\b'
	^H
	> print '\d'
	\d
	> print r'\b'
	\b

Try to get into the habit of using raw strings for regexps.



From tjreedy at udel.edu  Thu Jul  2 14:53:43 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 02 Jul 2009 14:53:43 -0400
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <h2ivno$cl8$1@ger.gmane.org>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
> 
> ## First snippet
> 
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
> 
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher

What happen is neither is None?



From james at agentultra.com  Thu Jul  2 14:54:49 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 02 Jul 2009 14:54:49 -0400
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
	<851vozf4rh.fsf@agentultra.com>
	<cd3362ac-e189-4dea-93d5-06db3aaafd29@c36g2000yqn.googlegroups.com>
Message-ID: <85ws6qewzq.fsf@agentultra.com>

masher <vertespain at gmail.com> writes:

> On Jul 2, 12:06?pm, J Kenneth King <ja... at agentultra.com> wrote:
>> masher <vertesp... at gmail.com> writes:
>> > My questions, then, is: Is there a more elegant/pythonic way of doing
>> > what I am trying to do with the current Pool class?
>>
>> Forgive me, I may not fully understand what you are trying to do here
>> (I've never really used multiprocessing all that much)...
>>
>> But couldn't you just assign your own Queue object to the Pool instance?
>
> That's basically my question. It does not appear as though there is
> any straightforward way of doing this because of the design of Pool's
> __init__ method, which passes _taskqueue to several functions. Hence,
> even if I were to reassign _taskqueue after __init__, that wouldn't
> change anything.

I think I understand.

There are ways to modify the class before instantiating it, but even the
most clever or elegant solution will still smell funny.  I suppose this
might be worth submitting as a feature suggestion to the multiprocessing
project.

Best of luck.


From rdrehoff at technotraining.net  Thu Jul  2 14:57:40 2009
From: rdrehoff at technotraining.net (Rich Drehoff)
Date: Thu, 2 Jul 2009 14:57:40 -0400
Subject: Intro to Python class, 7/21-23, Ft Worth TX
Message-ID: <000901c9fb46$faa21ae0$efe650a0$@net>

We are looking for someone that can help with the subject class, Intro to
Python class, 7/21-23, Ft Worth TX.  Please let me know if you can help.
Would need your resume and best possible daily rate.

 

Best regards,

 

Rich Drehoff

TechnoTraining, Inc.

328 Office Square Lane, Ste. 202, Virginia Beach, VA 23462-3648

(757) 425-0728 x15 / (757) 425-7323 Fax

Email: RDrehoff at TechnoTraining.net

Website: www.TechnoTraining.net <http://www.technotraining.net/> 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/643498d7/attachment.html>

From andrew at acooke.org  Thu Jul  2 15:07:20 2009
From: andrew at acooke.org (andrew cooke)
Date: Thu, 2 Jul 2009 15:07:20 -0400 (CLT)
Subject: Suppressing Implicit Chained Exceptions (Python 3.0)
Message-ID: <7915bc3d5213848b805f461940e3cbec.squirrel@localhost>

David Bolen wrote:
> "andrew cooke" <andrew at acooke.org> writes:
>
>> However, when printed via format_exc(), this new exception still has
the old exception attached via the mechanism described at
>> http://www.python.org/dev/peps/pep-3134/ (this is Python 3.0).
>
> If you're in control of the format_exc() call, I think the new chain
keyword parameter can disable this and restore the old behavior.
>
> If you're not in control of the traceback display, I'm not sure there's
an easy way to prevent it, given that displaying chained exceptions is
the default mode.

Yeah, that's the impression I got too.

Just in case it wasn't clear, I'd like the chaining not to exist at all in
this case), so that it doesn't appear in format_exc outside my control.

Thanks,
Andrew






From thudfoo at opensuse.us  Thu Jul  2 15:10:41 2009
From: thudfoo at opensuse.us (member thudfoo)
Date: Thu, 2 Jul 2009 12:10:41 -0700
Subject: Open Source RSS Reader in Python?
In-Reply-To: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <3d881a310907021210haabc998x9e4f678299716462@mail.gmail.com>

On Wed, Jul 1, 2009 at 4:18 PM, Alex<alex.lavoro.propio at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?
> --
> http://mail.python.org/mailman/listinfo/python-list
>

rawdog is an RSS Aggregator Without Delusions Of Grandeur. It is a
"river of news"-style aggregator: it uses feedparser to download feeds
in RSS, Atom and a variety of other formats, and (by default) produces
static HTML pages containing the newest articles in date order. For
example, rawdog's default configuration produces output that looks
like this:

http://offog.org/code/rawdog.html


From http  Thu Jul  2 15:13:48 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 12:13:48 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <7x63eahp8z.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> These two snippets of code are functionally identical. Which would you
> use and why?

Both are terrible.  I can't tell what you're really trying to do.  As
Terry Reedy points out, the case where self.higher and self.lower are
both not None is not handled.  If you want to explicitly return None,
use "return None" rather than "return".  Generally, having a special
value like None to denote a missing datum was considered standard
practice a few decades ago, but these days in some circles it's
treated as something of a code smell.  You may want to look for
some other representation instead.

Most importantly, whatever code you write, put in an explanatory
comment saying what the real goal is.


From usernet at ilthio.net  Thu Jul  2 15:16:25 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 19:16:25 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
Message-ID: <dI73m.3603$Jb1.569@flpi144.ffdc.sbc.com>

On 2009-07-02, Duncan Booth <duncan.booth at invalid.invalid> wrote:
> so apart from reversing the order of the comparisons once you've dropped 
> the redundant test it is the same as the first one.

I try to evaluate what you have given regardless of what Booth pointed out.
So, I will only evaluate the first line as it contains most of what I want
to illistrate.

> Simon Forman <sajmikins at gmail.com> wrote:
>> if self.higher is self.lower is None: return

I *really* don't like the fact that you don't specify a return value here
when you have specified a return value for the other conditions.  Obviously
it is possible that something will be looking at the return value for this
function (ie, it would not be a void function() in C).  I had to lookup to
make sure what Python would return in such a case.  If you want the
condition to return something then you should specify what you are
returning.  Specifing 'return None' is much clearer then relying on default
behavior.

I always prefer to see a:
	
	condition:
		operation

structure to my code.  It is the way it is almost always see in Python and
in other languages.  Putting it on one line doesn't save you anything and
it makes it easier to miss something.

I have no particular problem with running the is statements together as an
extended if statement together when it makes it clearer to do so.  The fact
that you want all of them to be the same object is clear.  I do have some
wroblem in this instance because you are referencing "is" against an
instance of a builtin object.

The fact that you used is instead of == for this particular instance
throws me a little because of the use of None.  I wouldn't think second
about it if it was a user defined object.  I have to wonder whether all
objects that are assigned the value of None are actually re-referenced
to the origional None object?  Could deep copy style operations create
two equivilant but different copys of none?  The same problems may be
encounted from any builtin objects such as number literals.

Had None not been specified I would be fine with stringing the comparison
together:

# if all three objects are the same instance, return None
if object1 is object2 is object3:
	return None:

Because of this pecularity, I think that it would be clearer to break the
ifs for simularity and equality:

if object1 is object2:
	if object1 == None:
		return None
	else:
		return object1
else:
	if object1 == None:
		return Object2
	elif object2 == None::
		return Object1
	else:
		# what do we do if neither object == None?
		raise houstonWeHaveAProblemException


From Scott.Daniels at Acm.Org  Thu Jul  2 15:57:57 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Thu, 02 Jul 2009 12:57:57 -0700
Subject: question of style
In-Reply-To: <Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
Message-ID: <gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>

Duncan Booth wrote:
> Simon Forman <sajmikins at gmail.com> wrote:
>> ...
>> if self.higher is self.lower is None: return
>> ...

> As a matter of style however I wouldn't use the shorthand to run two 'is' 
> comparisons together, I'd write that out in full if it was actually needed 
> here.

Speaking only to the style issue, when I've wanted to do something like
that, I find:

       if self.higher is None is self.lower:
           ...

more readable, by making clear they are both being compared to a
constant, rather than compared to each other.

More often, I've used code like:

       if <expr1> is not None is not <expr2>:
           ...

since I am usually working on non-defaulting cases in the body.
I find the form above simpler to read than:

       if <expr1> is not None and <expr2> is not None:
           ...

I do draw the line at two, though, and with three or more I'll
paren-up a list of parallel comparisons:

       if (<expr1> is not None
         and <expr2> is not None
         and <expr3> is not None):
           ...

--Scott David Daniels
Scott.Daniels at Acm.Org


From http  Thu Jul  2 16:02:58 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 13:02:58 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <7xws6qrgy5.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
> 
> What do you think?

I'm not sure, but my guess is that what you are really trying to write
is something like this:

   # self.higher and self.lower are each either "available" (i.e.  are
   # not None), or unavailable (are None).  Return the highest of the
   # available values.  If no value is available, return None.

   if self.higher is not None: 
       return self.higher
   elif self.lower is not None: 
       return self.lower
   else: 
       return None


From sanket.s.patel at gmail.com  Thu Jul  2 16:07:54 2009
From: sanket.s.patel at gmail.com (sanket)
Date: Thu, 2 Jul 2009 13:07:54 -0700 (PDT)
Subject: how to spawn a process under different user
Message-ID: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>

Hello All,

I am trying to use python's subprocess module to launch a process.
but in order to do that I have to change the user.

I am not getting any clue how to do that?
so can anyone please tell me How can I spawn a process under different
user than currently I am logging in as.

Thank you,
sanket


From max at alcyone.com  Thu Jul  2 16:08:57 2009
From: max at alcyone.com (Erik Max Francis)
Date: Thu, 02 Jul 2009 13:08:57 -0700
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
> 
> ## First snippet
> 
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
> 
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
> 
> What do you think?

Explicit is always better, `return None` when that is your intent. 
`return` shouts to the reader, "I want to get out of this function now, 
and no one cares about the return result."

Personally, I only use the one-liner if/else clauses if it's an 
extremely trivial condition, and even then, usually not there.  (The 
only place I use it consistently is `if __name__ == '__main__': 
main()`.)  If it's part of something more important that needs 
inspection -- as this obviously does given the questions you've had 
about it, doesn't skip space.  Newlines are free.

Even when expanding about the first test, there's no reason to do 
chained `if`s.  One `if` with an `and` works just fine.

Paul Rubin's looked to be the best overall replacement, as the logic 
here looks strangely turned inside out.  You're obviously looking for 
which one _isn't_ `None`, so write the tests that way.  It's much easier 
for everyone else (including your potential future self) to follow.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   They are ill discoverers that think there is no land when they can
    see nothing but sea. -- Francis Bacon


From usernet at ilthio.net  Thu Jul  2 16:27:33 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 20:27:33 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
Message-ID: <VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>

On 2009-07-02, Scott David Daniels <Scott.Daniels at Acm.Org> wrote:
> Duncan Booth wrote:
>> Simon Forman <sajmikins at gmail.com> wrote:
>> As a matter of style however I wouldn't use the shorthand to run two 'is' 
>> comparisons together, I'd write that out in full if it was actually needed 
>> here.

That part I don't really have a problem with.  The chained is statements
can actually be much clearer burying the tests into nested ifs.  Nested ifs
get the same result but they also give an immediate impression that the
control structure might be looking for more then a single test result.  I
have to walk through the ifs to see all of the potential results one is
looking for before I know what the entire control struture is doing.
Multiple is operators makes it clear that I just want everything to be the
same.  The same would not be true if the operators where not all equilance
operators ( is and == are clear as long as they are not mixed; but <, >=,
!= would be more confusing).

> Speaking only to the style issue, when I've wanted to do something like
> that, I find:
>        if self.higher is None is self.lower:
> more readable, by making clear they are both being compared to a
> constant, rather than compared to each other.

By comparing them to *any* constant with 'is' you end up with the same
potential problems as to whether something with a value of None is actually
None?  Is something with the value of 3 actually the same object as 3?
What about if I make a deep copy?  Can I have several objects with the
value of three, all the same 3 object, or maybe even a combination of 1
separate 3 object with two other objects of the same 3.

Is
	if self.higher == None == self.lower:
any more clear then:
	if self.higher == self.lower == None:
I don't personally have a problem with either.

> More often, I've used code like:
>        if <expr1> is not None is not <expr2>:
> since I am usually working on non-defaulting cases in the body.
> I find the form above simpler to read than:
>        if <expr1> is not None and <expr2> is not None:

This is a much more compicated expression.  With equality operators
everything is either the same or it isn't.   I can start from the first
variable and compare it to the second then to the third then ...  In the
case of the inequality, I have to start with the first and compare it to
all of the rest to make sure that none are the same.  Then I have to do the
same for each with the remaining.  This is much more difficult to do in my
head.  I requires much more thought, better left to a computer, when
evaluating the expression for myself.  Therefore, equalites are quick and
easy to keep straight whereas any inequalites are more error prone when
trying to evaluate how a section of code will react under different
circumstances.

> I do draw the line at two, though, and with three or more I'll
> paren-up a list of parallel comparisons:

As long as everything is an equality, then I don't mind comparing to the
end of an 70 column line.  Mixed types of equalities or inequalities
require too many operations mentally evaluate safely.


From bpytlik at sun.com  Thu Jul  2 16:31:35 2009
From: bpytlik at sun.com (Brock Pytlik)
Date: Thu, 02 Jul 2009 13:31:35 -0700
Subject: System default sys.path
In-Reply-To: <81a8195ca5ecf44f3bf9ddbfaae37bdc@preisshare.net>
References: <4A4C1FE4.1070901@sun.com>
	<81a8195ca5ecf44f3bf9ddbfaae37bdc@preisshare.net>
Message-ID: <4A4D1927.5070305@sun.com>

David Lyon wrote:
> On Wed, 01 Jul 2009 19:48:04 -0700, Brock Pytlik <bpytlik at Sun.COM> wrote:
>   
>> Hi, I'm trying to find a way to get the value sys.path would have on a 
>> particular system if python was started with an empty python path. I do 
>> want it to include the site specific additional paths. I know I can hack 
>> this information myself, 
>>     
>
> Copy the code out from site.py...
>
>   
Well, as far as I can tell, site does several things. It calls 
abs__file__ which, afaict, doesn't effect sys.path. Then it calls 
removeduppaths, which walks over sys.path. That means that sys.path has 
already been set by something at that point. So, how/where did sys.path 
get set then? Or is sys.path always empty there at startup and this code 
is just to handle other situations?

[snip]

Brock


From usernet at ilthio.net  Thu Jul  2 16:37:13 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 20:37:13 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
Message-ID: <ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>

On 2009-07-02, Paul Rubin <http> wrote:
[reformated with emphasis added]
>    #self.higher and self.lower are each either "available" (i.e.  are not
>    #None), or unavailable (are None).  [EMPHASIS] Return the highest of the
>    #available values. [/EMPHASIS]  If no value is available, return None.

Your code doesn't do what your comment says (notice EMPHASIS tags):

>    if self.higher is not None: 
>        return self.higher
>    elif self.lower is not None: 
>        return self.lower
>    else: 
>        return None

If lower is 5 and higher is 3, then it returns 3 because 3 != None in the
first if.


From dfstrauss at gmail.com  Thu Jul  2 16:49:00 2009
From: dfstrauss at gmail.com (Dawie Strauss)
Date: Thu, 2 Jul 2009 13:49:00 -0700 (PDT)
Subject: PyTextMagicSMS text messaging library released
Message-ID: <2b583f41-78d7-4a7e-a925-04934efe5458@m7g2000prd.googlegroups.com>

TextMagic (http://www.textmagic.com) offers a convenient way to send
text messages programmatically. This package provides a simple Python
API on top of the TextMagic HTTPS API.

Project documentation and source code is hosted at
http://code.google.com/p/textmagic-sms-api-python/

The package can be dowloaded from http://pypi.python.org/pypi/PyTextMagicSMS/



From user at example.net  Thu Jul  2 16:57:49 2009
From: user at example.net (superpollo)
Date: Thu, 02 Jul 2009 22:57:49 +0200
Subject: stringio+tarfile
Message-ID: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>

why the following does not work? can you help me correct (if possible)?

       1 import tarfile
       2 import StringIO
       3 sf1 = StringIO.StringIO("one\n")
       4 sf2 = StringIO.StringIO("two\n")
       5 tf = StringIO.StringIO()
       6 tar = tarfile.open(tf , "w")
       7 for name in [sf1 , sf2]:
       8     tar.add(name)
       9 print tf
      10 sf1.close()
      11 sf2.close()
      12 tf.close()
      13 tar.close()

tia


From mail at timgolden.me.uk  Thu Jul  2 16:58:03 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 02 Jul 2009 21:58:03 +0100
Subject: how to spawn a process under different user
In-Reply-To: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
Message-ID: <4A4D1F5B.6070605@timgolden.me.uk>

sanket wrote:
> Hello All,
> 
> I am trying to use python's subprocess module to launch a process.
> but in order to do that I have to change the user.
> 
> I am not getting any clue how to do that?
> so can anyone please tell me How can I spawn a process under different
> user than currently I am logging in as.

What platform are you on? If you are on Windows,
there was a thread on this subject some time in
the last month. (Short answer: switching user before
launching subprocess won't work; switching within
the subprocess will...)

TJG


From rschroev_nospam_ml at fastmail.fm  Thu Jul  2 17:28:19 2009
From: rschroev_nospam_ml at fastmail.fm (Roel Schroeven)
Date: Thu, 02 Jul 2009 23:28:19 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <h2i35q$mp4$01$1@news.t-online.com>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<h2i35q$mp4$01$1@news.t-online.com>
Message-ID: <UD93m.9416$IA6.7106@newsfe01.ams2>

Peter Otten schreef:
> Ulrich Eckhardt wrote:
> 
>> Bearophile wrote:
>>> Ulrich Eckhardt:
>>>> a way to automatically release the resource, something
>>>> which I would do in the destructor in C++.
>>> Is this helpful?
>>> http://effbot.org/pyref/with.htm
>> Yes, it aims in the same direction. However, I'm not sure this applies to
>> my case. The point is that the resource handle is not just used locally in
>> a restricted scope but it is allocated and stored. The 'with' is something
>> that makes sense in the context of mutex locking, where you have a
>> well-defined critical section. 
> 
> Isn't that exactly what RAII does?

RAII also works if the resource handle is stored, for example, in a data
member of an object. If that object is destroyed (because it goes out of
scope, or because it is deleted), the resource is automatically
destroyed too.

The way RAII works is actually the one thing from C++ that I miss in Python.

-- 
The saddest aspect of life right now is that science gathers knowledge
faster than society gathers wisdom.
  -- Isaac Asimov

Roel Schroeven


From http  Thu Jul  2 17:43:38 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 14:43:38 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
Message-ID: <7xocs2222d.fsf@ruckus.brouhaha.com>

Tim Harig <usernet at ilthio.net> writes:
> If lower is 5 and higher is 3, then it returns 3 because 3 != None in the
> first if.

Sorry, the presumption was that lower <= higher, i.e. the comparison
had already been made and the invariant was enforced by the class
constructor.  The comment should have been more explicit, I guess.


From sanket.s.patel at gmail.com  Thu Jul  2 17:56:30 2009
From: sanket.s.patel at gmail.com (sanket)
Date: Thu, 2 Jul 2009 14:56:30 -0700 (PDT)
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
Message-ID: <25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>

On Jul 2, 1:58?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> sanket wrote:
> > Hello All,
>
> > I am trying to use python's subprocess module to launch a process.
> > but in order to do that I have to change the user.
>
> > I am not getting any clue how to do that?
> > so can anyone please tell me How can I spawn a process under different
> > user than currently I am logging in as.
>
> What platform are you on? If you are on Windows,
> there was a thread on this subject some time in
> the last month. (Short answer: switching user before
> launching subprocess won't work; switching within
> the subprocess will...)
>
> TJG

Hi TJG,
Thanks for the reply.

I am using python 2.4 on centos.

Thanks,
sanket


From hannarosie at gmail.com  Thu Jul  2 18:05:46 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Thu, 2 Jul 2009 15:05:46 -0700
Subject: String to List Question
Message-ID: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>

Hi,

I am brand new to python and I love it, but I've been having some trouble
with a file parser that I've been working on. It contains lines that start
with a name and then continue with names, nicknames and phone numbers of
people associated with that name. I need to create a list of the names of
people associated with each singular person (the first name in each line).
Each name/phone number is separated by a tab but if someone doesn't have a
nickname there are two tabs between their name and number.

I've been trying to figure out how to test for two tabs, skip over these
people and move onto the next name but I just can't figure out how that will
work in python.

Any help would be greatly appreciated!

Thanks,
Hanna
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/84d46e24/attachment.html>

From allen.fowler at yahoo.com  Thu Jul  2 18:06:17 2009
From: allen.fowler at yahoo.com (Allen Fowler)
Date: Thu, 2 Jul 2009 15:06:17 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP:  How to define API?
Message-ID: <115250.26948.qm@web45607.mail.sp1.yahoo.com>


I have an (in-development) python system that needs to shuttle events / requests around over the network to other parts of itself.   It will also need to cooperate with a .net application running on yet a different machine.

So, naturally I figured some sort of HTTP event / RPC type of would be a good idea?

Are there any modules I should know about, or guidelines I could read, that could aid me in the design of the API?    


Thank you,
:)


      



From usernet at ilthio.net  Thu Jul  2 18:14:18 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:14:18 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
Message-ID: <_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>

On 2009-07-02, Paul Rubin <http> wrote:
> Tim Harig <usernet at ilthio.net> writes:
>> If lower is 5 and higher is 3, then it returns 3 because 3 != None in the
>> first if.
> Sorry, the presumption was that lower <= higher, i.e. the comparison
> had already been made and the invariant was enforced by the class
> constructor.  The comment should have been more explicit, I guess.

That being the case, it might be a good idea either to handle the situation
and raise an exception or add:

assert self.lower <= self.higher

That way an exception will be raised if there is an error somewhere else
in the code rather then silently passing a possibly incorrect value.


From philip at semanchuk.com  Thu Jul  2 18:15:03 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 2 Jul 2009 18:15:03 -0400
Subject: String to List Question
In-Reply-To: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
References: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
Message-ID: <76DF2C44-9A40-4FC9-AA20-CEDC3ED37806@semanchuk.com>


On Jul 2, 2009, at 6:05 PM, Hanna Michelsen wrote:

> Hi,
>
> I am brand new to python and I love it, but I've been having some  
> trouble
> with a file parser that I've been working on. It contains lines that  
> start
> with a name and then continue with names, nicknames and phone  
> numbers of
> people associated with that name. I need to create a list of the  
> names of
> people associated with each singular person (the first name in each  
> line).
> Each name/phone number is separated by a tab but if someone doesn't  
> have a
> nickname there are two tabs between their name and number.
>
> I've been trying to figure out how to test for two tabs, skip over  
> these
> people and move onto the next name but I just can't figure out how  
> that will
> work in python.
>
> Any help would be greatly appreciated!

Hi Hanna,
Are you familiar with a string's split() function? It sounds like just  
what you need.

http://docs.python.org/library/stdtypes.html#str.split

HTH
Philip



From allen.fowler at yahoo.com  Thu Jul  2 18:17:56 2009
From: allen.fowler at yahoo.com (Allen Fowler)
Date: Thu, 2 Jul 2009 15:17:56 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP:  How to define API?
Message-ID: <219972.64445.qm@web45607.mail.sp1.yahoo.com>





> I have an (in-development) python system that needs to shuttle events / requests 
> around over the network to other parts of itself.   It will also need to 
> cooperate with a .net application running on yet a different machine.
> 
> So, naturally I figured some sort of HTTP event / RPC type of would be a good 
> idea?
> 
> Are there any modules I should know about, or guidelines I could read, that 
> could aid me in the design of the API?    
> 
> 


To clarify:

Each message would be <1KB of data total, and consist of some structured object containing strings, numbers, dates, etc.

For instance there would be an "add user" request that would contain one or more User objects each having a number of properties like:

- Full Name
- Username
- Password
- Email addresses (a variable length array)
- Street Address line1
- Street Address line1
- Street Address line1
- City
- State
- Zip
- Sign Up Date

.... and so on.


Since I need to work with other platforms, pickle is out...  what are the alternatives?  XML? JSON?

How should I formally define each of the valid messages and objects?

Thank you,
:)



      



From mccdo at iastate.edu  Thu Jul  2 18:22:07 2009
From: mccdo at iastate.edu (Doug McCorkle)
Date: Thu, 2 Jul 2009 17:22:07 -0500
Subject: Detecting platform architecture with Parallels and Win XP x64
Message-ID: <8B80C75F-1F27-4E65-8BAE-C77441235943@iastate.edu>

Hello,

I am using Python 2.5.4 on Windows XP x64 with Parallels. When I try  
to use:

distutils.util.get_platform
sys.platform

I always get win32 but if I use:

platform.architecture()

with the amd64 installer I get 64bit for the first argument. Is there  
a way to detect win64 without having to use the python executable to  
see if the application is on a 64bit architecture? Thanks.

Doug




From usernet at ilthio.net  Thu Jul  2 18:27:05 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:27:05 GMT
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
	<25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>
Message-ID: <Zua3m.3615$Jb1.1092@flpi144.ffdc.sbc.com>

On 2009-07-02, sanket <sanket.s.patel at gmail.com> wrote:
>> sanket wrote:
>> > I am trying to use python's subprocess module to launch a process.
>> > but in order to do that I have to change the user.
> I am using python 2.4 on centos.

I have never done this in python; but, using the normal system calls in C
the process is basically:
	
	1. fork() a  new process
	2. the child process changes its user id with setreuid() and
		possibly its group id with setregid()
	3. then the child exec()s new process which replaces itself

All of the necessary functions should be under the os module on POSIX
operating systems.


From clp2 at rebertia.com  Thu Jul  2 18:27:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 2 Jul 2009 15:27:23 -0700
Subject: XML(JSON?)-over-HTTP: How to define API?
In-Reply-To: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
References: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
Message-ID: <50697b2c0907021527j6cd6cfb6o734c989b71da77b1@mail.gmail.com>

On Thu, Jul 2, 2009 at 3:06 PM, Allen Fowler<allen.fowler at yahoo.com> wrote:
>
> I have an (in-development) python system that needs to shuttle events / requests around over the network to other parts of itself. ? It will also need to cooperate with a .net application running on yet a different machine.
>
> So, naturally I figured some sort of HTTP event / RPC type of would be a good idea?
>
> Are there any modules I should know about, or guidelines I could read, that could aid me in the design of the API?

http://en.wikipedia.org/wiki/Representational_State_Transfer
(aka REST)

O'Reilly also has a book on the subject.

Cheers,
Chris
-- 
http://blog.rebertia.com


From http  Thu Jul  2 18:29:49 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 15:29:49 -0700
Subject: XML(JSON?)-over-HTTP:  How to define API?
References: <mailman.2520.1246573083.8015.python-list@python.org>
Message-ID: <7xprcipvky.fsf@ruckus.brouhaha.com>

Allen Fowler <allen.fowler at yahoo.com> writes:
> Since I need to work with other platforms, pickle is out...  what
> are the alternatives?  XML? JSON?

json is the easiest to prototype with and is less bureaucratic.  xml
has more serious tools for schema specification and validation etc.
You could start with json and switch later.  As for the rpc mechanism,
using urllib and one of the HTTP server modules is probably simplest.


From charles at declareSub.com  Thu Jul  2 18:30:43 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Thu, 2 Jul 2009 18:30:43 -0400
Subject: XML(JSON?)-over-HTTP:  How to define API?
In-Reply-To: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
References: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
Message-ID: <35DA358F-DFDC-425D-BD68-AFEF2024F537@declareSub.com>


On Jul 2, 2009, at 6:06 PM, Allen Fowler wrote:

>
> I have an (in-development) python system that needs to shuttle  
> events / requests around over the network to other parts of  
> itself.   It will also need to cooperate with a .net application  
> running on yet a different machine.
>
> So, naturally I figured some sort of HTTP event / RPC type of would  
> be a good idea?
>
> Are there any modules I should know about, or guidelines I could  
> read, that could aid me in the design of the API?
>
>
> Thank you,
> :)

I'd suggest the O'Reilly book "RESTful Web Services".

Charles Yeomans


From http  Thu Jul  2 18:32:27 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 15:32:27 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
Message-ID: <7xljn6pvgk.fsf@ruckus.brouhaha.com>

Tim Harig <usernet at ilthio.net> writes:
> That being the case, it might be a good idea either to handle the situation
> and raise an exception or add:
> 
> assert self.lower <= self.higher
> 
> That way an exception will be raised if there is an error somewhere else
> in the code rather then silently passing a possibly incorrect value.

Well, that assert is not right because you have to handle the case
where one of the values is None.  The general sentiment is reasonable
though, if you're concerned that the precondition may not be valid.


From rhodri at wildebst.demon.co.uk  Thu Jul  2 18:38:49 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 02 Jul 2009 23:38:49 +0100
Subject: String to List Question
In-Reply-To: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
References: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
Message-ID: <op.uwgo6zj7a8ncjz@gnudebst>

On Thu, 02 Jul 2009 23:05:46 +0100, Hanna Michelsen <hannarosie at gmail.com>  
wrote:

> Hi,
>
> I am brand new to python and I love it, but I've been having some trouble
> with a file parser that I've been working on. It contains lines that  
> start
> with a name and then continue with names, nicknames and phone numbers of
> people associated with that name. I need to create a list of the names of
> people associated with each singular person (the first name in each  
> line).
> Each name/phone number is separated by a tab but if someone doesn't have  
> a
> nickname there are two tabs between their name and number.
>
> I've been trying to figure out how to test for two tabs, skip over these
> people and move onto the next name but I just can't figure out how that  
> will
> work in python.

You might find the csv module in the standard library does a lot of the
hard work for you: http://docs.python.org/library/csv.html

You can define yourself a reader that splits the input on tabs, and
then see how long the rows it returns are.  Something like this
(untested):

import csv

for row in csv.reader(open("phone_numbers.txt", "rb"), delimiter='\t'):
     if len(row) > 1:
         # Do your stuff

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From Russ.Paielli at gmail.com  Thu Jul  2 18:41:56 2009
From: Russ.Paielli at gmail.com (Russ P.)
Date: Thu, 2 Jul 2009 15:41:56 -0700 (PDT)
Subject: Is Psyco good for Python 2.6.1?
Message-ID: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>

I need to speed up some Python code, and I discovered Psyco. However,
the Psyco web page has not been updated since December 2007. Before I
go to the trouble of installing it, does anyone know if it is still
good for Python 2.6.1? Thanks.


From usernet at ilthio.net  Thu Jul  2 18:49:52 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:49:52 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
Message-ID: <kQa3m.3616$Jb1.1642@flpi144.ffdc.sbc.com>

On 2009-07-02, Paul Rubin <http> wrote:
> Tim Harig <usernet at ilthio.net> writes:
>> That being the case, it might be a good idea either to handle the situation
>> and raise an exception or add:
>> assert self.lower <= self.higher
>> That way an exception will be raised if there is an error somewhere else
>> in the code rather then silently passing a possibly incorrect value.
> Well, that assert is not right because you have to handle the case
> where one of the values is None.  The general sentiment is reasonable
> though, if you're concerned that the precondition may not be valid.

Sorry, it worked under 2.5:

2.5	>>> lower = None
2.5	>>> higher = 10
2.5	>>> assert lower <= higher
2.5	>>> assert higher < lower
2.5	Traceback (most recent call last):
2.5	  File "<stdin>", line 1, in <module>
2.5	AssertionError
2.5	>>> higher = -10
2.5	>>> assert lower <= higher
2.5	>>> assert higher < lower
2.5	Traceback (most recent call last):
2.5	  File "<stdin>", line 1, in <module>
2.5	AssertionError

None seems to have been evaluated less then any integer.  The same isn't
true under 3.0:

3.0	>>> lower = None
3.0	>>> higher = 10
3.0	>>> assert lower <= higher
3.0	Traceback (most recent call last):
3.0	  File "<stdin>", line 1, in <module>
3.0	TypeError: unorderable types: NoneType() <= int()

Then it is probably easier to just handle it in the conditionals and raise
an exception manually.


From usernet at ilthio.net  Thu Jul  2 18:56:49 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:56:49 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
	<kQa3m.3616$Jb1.1642@flpi144.ffdc.sbc.com>
Message-ID: <RWa3m.3617$Jb1.2835@flpi144.ffdc.sbc.com>

On 2009-07-02, Tim Harig <usernet at ilthio.net> wrote:
> Sorry, it worked under 2.5:
[SNIP]
> None seems to have been evaluated less then any integer.  The same isn't
> true under 3.0:

None seem to have been evaluated less then any non-negative integer
including 0.


From sajmikins at gmail.com  Thu Jul  2 19:04:31 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 16:04:31 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
Message-ID: <f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>

On Jul 2, 4:08?pm, Erik Max Francis <m... at alcyone.com> wrote:
> Simon Forman wrote:
> > Hey I was hoping to get your opinions on a sort of minor stylistic
> > point.
> > These two snippets of code are functionally identical. Which would you
> > use and why?
> > The first one is easier [for me anyway] to read and understand, but
> > slightly less efficient, while the second is [marginally] harder to
> > follow but more efficient.
>
> > ## First snippet
>
> > if self.higher is self.lower is None: return
> > if self.lower is None: return self.higher
> > if self.higher is None: return self.lower
>
> > ## Second snippet
>
> > if self.higher is None:
> > ? ? if self.lower is None:
> > ? ? ? ? return
> > ? ? return self.lower
> > if self.lower is None:
> > ? ? return self.higher
>
> > What do you think?
>
> Explicit is always better, `return None` when that is your intent.
> `return` shouts to the reader, "I want to get out of this function now,
> and no one cares about the return result."
>
> Personally, I only use the one-liner if/else clauses if it's an
> extremely trivial condition, and even then, usually not there. ?(The
> only place I use it consistently is `if __name__ == '__main__':
> main()`.) ?If it's part of something more important that needs
> inspection -- as this obviously does given the questions you've had
> about it, doesn't skip space. ?Newlines are free.
>
> Even when expanding about the first test, there's no reason to do
> chained `if`s. ?One `if` with an `and` works just fine.
>
> Paul Rubin's looked to be the best overall replacement, as the logic
> here looks strangely turned inside out. ?You're obviously looking for
> which one _isn't_ `None`, so write the tests that way. ?It's much easier
> for everyone else (including your potential future self) to follow.
>


Thanks for all the great feedback!

Some notes:

This code is part of a delete() method for a binary tree
implementation. "None" is used to simulate a NULL pointer. In the case
where both children are non-None the code goes on to handle that.

None is a "unitary" or "singleton" value, so "is" is the right
comparison operator to use with it, at least in this "imitation
pointer" usage.

The bare return was used both to preclude executing the rest of the
function and to return None. (I sometimes use "return # None" with
None in a comment to note that the return value is used. Also, I will
put "# return" or "# return None" at the end of a function if the
returning-of-None is important to the implementation of whatever.
I've never used dis.dis() to check the bytecodes, but I wouldn't be
surprised to find that the compiler generated the same bytecode
whether you explicitly state the return or comment it out.)

In any event, as Duncan Booth pointed out, the entire line was
redundant so the issue is somewhat moot in this particular case.

As for one-line control flow statements in python, I usually refrain
but this code wasn't originally meant for public viewing.

Last but not least, the logic may seem backwards but it's actually
correct. If you check for non-None (NULL) -ness and return the thing
you checked, rather than checking for None-ness and returning the
other, the case where both are non-None is not handled correctly.

Thanks again,
~Simon

FWIW, here's the BinaryTree class, the code is in the _delete_me()
method.

from random import random


class BinaryTree:
    '''
    A Binary Tree implementation. Provides:

        get(key) - Return item for key or None.

        insert(key, value) - Insert value under key, replacing old
ones.

        delete(key) - Delete value under key if any.

        keys() - Iterate through the keys in sort order.
        values() - Iterate through the values in sort order.
        items() - Iterate through (key, value) pairs in sort order.

    '''
    def __init__(self, key, value):
        self.key = key
        self.value = value
        self.higher = self.lower = None

    def get(self, key):
        '''
        Return item for key or None.
        '''
        if key == self.key:
            return self.value
        if key < self.key and self.lower is not None:
            return self.lower.get(key)
        if self.higher is not None:
            assert key > self.key
            return self.higher.get(key)

    def insert(self, key, value):
        '''
        Insert value under key, replacing old ones.
        '''
        if key == self.key:
            self.value = value
        elif key < self.key:
            if self.lower is None:
                self.lower = BinaryTree(key, value)
            else:
                self.lower.insert(key, value)
        else:
            assert key > self.key
            if self.higher is None:
                self.higher = BinaryTree(key, value)
            else:
                self.higher.insert(key, value)

    def delete(self, key):
        '''
        Delete value under key if any.
        '''
        if key < self.key and self.lower is not None:
            self.lower = self.lower.delete(key)
        elif key > self.key and self.higher is not None:
            self.higher = self.higher.delete(key)
        elif key == self.key:
            return self._delete_me()
        return self

    def _delete_me(self):
        if self.lower is None: return self.higher
        if self.higher is None: return self.lower

        # Two children...
        try:
            side = self._which_side
        except AttributeError:
            side = bool(int(random() * 2))

        # Alternate sides, should help keep tree balanced.
        self._which_side = not side

        method = self._delete_lower if side else self._delete_higher
        return method()

    def _delete_lower(self):
        next = self.lower
        while next.higher is not None: next = next.higher
        self.key = next.key
        self.value = next.value
        self.lower = self.lower.delete(self.key)
        return self

    def _delete_higher(self):
        next = self.higher
        while next.lower is not None: next = next.lower
        self.key = next.key
        self.value = next.value
        self.higher = self.higher.delete(self.key)
        return self

    def keys(self):
        '''
        Iterate through the keys in sort order.
        '''
        for key, value in self.items():
            yield key

    def values(self):
        '''
        Iterate through the values in sort order.
        '''
        for key, value in self.items():
            yield value

    def items(self):
        '''
        Iterate through (key, value) pairs in sort order.
        '''
        if self.lower is not None:
            for kv in self.lower.items():
                yield kv
        yield self.key, self.value
        if self.higher is not None:
            for kv in self.higher.items():
                yield kv




From barry at python.org  Thu Jul  2 19:10:39 2009
From: barry at python.org (Barry Warsaw)
Date: Thu, 2 Jul 2009 19:10:39 -0400
Subject: Python 3.0 (pinin' for the fjords)
Message-ID: <A94443C0-1CBB-4E54-82C9-CAD8425F822D@python.org>

Now that Python 3.1 is out, it seems there's been some confusion as to  
whether there will be one last Python 3.0 release, i.e. Python 3.0.2.

At the PyCon 2009 language summit it was decided that there will be  
*no* Python 3.0.2.  Python 3.0 is different than all other releases.   
There will be no last maintenance release and no ongoing security  
releases.  Python 3.1 is the replacement for Python 3.0, and it's  
release schedule was accelerated specifically so that production users  
would be able to switch immediately.

If you're using Python 3, you are strongly urged to update to Python  
3.1.  Python 3.1 will be a 'normal' release in that we're making all  
the guarantees that we make for other releases.  It is likely that  
Python 3.2 is 18-24 months away, there will be Python 3.1.x  
maintenance releases, and there will be one last Python 3.1.x release  
after the final release of Python 3.2.

Cheers,
-Barry

-------------- next part --------------
A non-text attachment was scrubbed...
Name: PGP.sig
Type: application/pgp-signature
Size: 849 bytes
Desc: This is a digitally signed message part
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/a07c4c0c/attachment.sig>

From sajmikins at gmail.com  Thu Jul  2 19:13:47 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 16:13:47 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
Message-ID: <529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com>

On Jul 2, 3:57?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> Duncan Booth wrote:
> > Simon Forman <sajmik... at gmail.com> wrote:
> >> ...
> >> if self.higher is self.lower is None: return
> >> ...
> > As a matter of style however I wouldn't use the shorthand to run two 'is'
> > comparisons together, I'd write that out in full if it was actually needed
> > here.
>
> Speaking only to the style issue, when I've wanted to do something like
> that, I find:
>
> ? ? ? ?if self.higher is None is self.lower:
> ? ? ? ? ? ?...
>
> more readable, by making clear they are both being compared to a
> constant, rather than compared to each other.

I was going to do it that way for aesthetics if nothing else, but in
this particular code "self.higher is self.lower" could only have been
True if they were both None, so the final "is None" was redundant and
I only included it as a "just-in-case" check in case someone someday
used the code in such a way as to assign the same object (not None) to
both self.higher and self.lower...  Totally pointless, I'm sorry to
say.  I'm glad the whole line was redundant really.

> More often, I've used code like:
>
> ? ? ? ?if <expr1> is not None is not <expr2>:
> ? ? ? ? ? ?...
>
> since I am usually working on non-defaulting cases in the body.
> I find the form above simpler to read than:
>
> ? ? ? ?if <expr1> is not None and <expr2> is not None:
> ? ? ? ? ? ?...
>
> I do draw the line at two, though, and with three or more I'll
> paren-up a list of parallel comparisons:
>
> ? ? ? ?if (<expr1> is not None
> ? ? ? ? ?and <expr2> is not None
> ? ? ? ? ?and <expr3> is not None):
> ? ? ? ? ? ?...
>
> --Scott David Daniels
> Scott.Dani... at Acm.Org



From mensanator at aol.com  Thu Jul  2 20:34:31 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 2 Jul 2009 17:34:31 -0700 (PDT)
Subject: Is Psyco good for Python 2.6.1?
References: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
Message-ID: <e4fe73ac-fa53-4614-b5b5-6ce489b3062a@c36g2000yqn.googlegroups.com>

On Jul 2, 5:41?pm, "Russ P." <Russ.Paie... at gmail.com> wrote:
> I need to speed up some Python code, and I discovered Psyco. However,
> the Psyco web page has not been updated since December 2007. Before I
> go to the trouble of installing it, does anyone know if it is still
> good for Python 2.6.1? Thanks.

Go back to the web site and look at the download page.

Usually, the download page will list various versions
to use with various Python versions. If it lists a
2.4 version, a 2.5 version, but no 2.6 version, most likely
the authors haven't yet made a 2.6 version so you're SOL.

Even that isn't guaranteed to always work. For instance,
the authors of the smpy module didn't think they needed
a seperate 2.6 version (and didn't make any effort to
actually try it 2.6). Turned out to be dead wrong on that
and had to scramble to release a fix.


From http  Thu Jul  2 20:57:15 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 17:57:15 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
	<kQa3m.3616$Jb1.1642@flpi144.ffdc.sbc.com>
Message-ID: <7x8wj61t3o.fsf@ruckus.brouhaha.com>

Tim Harig <usernet at ilthio.net> writes:
> > Well, that assert is not right because you have to handle the case
> > where one of the values is None...  
> Sorry, it worked under 2.5:

Well, it didn't crash under 2.5.  Whether the result was correct
is a different question.  

> None seems to have been evaluated less then any integer.  The same isn't
> true under 3.0:

But the original code didn't specify the non-None values to be
integers.  Really, it's unwise to rely on an ordering relation between
None and values of arbitrary other types, unless supportable by a
clear specification, but even then, it's a code smell.

> 3.0	TypeError: unorderable types: NoneType() <= int()

That is far preferable to what 2.x does.


From rylesny at gmail.com  Thu Jul  2 21:03:59 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 18:03:59 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<h2i35q$mp4$01$1@news.t-online.com>
Message-ID: <5a6891ba-bb93-41ab-8ba5-acb23bde3ae9@a7g2000yqk.googlegroups.com>

> You can go ahead and implement a __del__() method. It will often work in
> CPython, but you get no guarantees, especially when you have reference
> cycles and with other Python implementations that don't use refcounting.

And for resources whose lifetime is greater than your process (e.g. a
file), you can also use the atexit module to help ensure they are
cleaned/reclaimed at shutdown. One way to do this is to maintain a
weak dictionary (from the weakref module) to your objects and install
a handler which iterates this. This is useful for not only dealing
with reference cycles, but for objects which may exist at the time the
interpreter exits. These may not be deleted.

http://docs.python.org/reference/datamodel.html#object.__del__


From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:37 -0300
Subject: stringio+tarfile
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <op.uwgt4tlux6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 17:57:49 -0300, superpollo <user at example.net> escribi?:

> why the following does not work? can you help me correct (if possible)?

Explain "does not work" please. Does it raise an exception? Which one?
Please post the complete traceback. You don't get the expected result?
Tell us what did you expect and what you actually get. If you provide this
information, it's a lot easier for people to look at your problem and
eventually find a solution.

Fortunately my crystall ball is back from the repair shop and I can guess
that you want to create a tar file in memory, and add some content from a
memory buffer too, right?
I didn't run your code but I can see two problems:

>        5 tf = StringIO.StringIO()
>        6 tar = tarfile.open(tf , "w")

The first argument to tarfile.open is the *name* of the file to
open/create. In this case you don't have a real file, but a StringIO
object; use the fileobj argument instead: tarfile.open(fileobj=tf,
mode="w")
See http://docs.python.org/library/tarfile.html#tarfile.open

>        7 for name in [sf1 , sf2]:
>        8     tar.add(name)

The add method takes the *name* of a file to add to the archive. Again,
you don't have a real file to add; try the addfile method instead.
See http://docs.python.org/library/tarfile.html#tarfile.TarFile.add


-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:42 -0300
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
	<25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>
	<Zua3m.3615$Jb1.1092@flpi144.ffdc.sbc.com>
Message-ID: <op.uwguqbqjx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 19:27:05 -0300, Tim Harig <usernet at ilthio.net>
escribi?:
> On 2009-07-02, sanket <sanket.s.patel at gmail.com> wrote:
>>> sanket wrote:

>>> > I am trying to use python's subprocess module to launch a process.
>>> > but in order to do that I have to change the user.
>> I am using python 2.4 on centos.
>
> I have never done this in python; but, using the normal system calls in C
> the process is basically:
> 	
> 	1. fork() a  new process
> 	2. the child process changes its user id with setreuid() and
> 		possibly its group id with setregid()
> 	3. then the child exec()s new process which replaces itself
>
> All of the necessary functions should be under the os module on POSIX
> operating systems.

How to do that using the subprocess module: write a function for item (2)
above and pass it as the preexec_fn argument to Popen. preexec_fn is
executed after fork() and before exec()

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:45 -0300
Subject: dealloc function in python extend c module
References: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
	<8599A253-D2C9-4EE4-AF4F-AEF658BA2033@semanchuk.com>
Message-ID: <op.uwgv3ywwx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 14:22:53 -0300, Philip Semanchuk
<philip at semanchuk.com> escribi?:
> On Jul 2, 2009, at 2:11 AM, Shen, Yu-Teh wrote:
>
>> I create my extend type something like  
>> http://www.python.org/doc/current/extending/newtypes.html.
>> And my type has a member which is a pointer point to my allocate
>> memory ( no ref count).
>> ex:
>> ---------------------------------------------------
>> typedef struct {
>>    PyObject_HEAD
>>    /* Type-specific fields go here. */
>>    mytype *p;
>> } noddy_NoddyObject;
>>
>> And i write dealloc function like this:
>> ---------------------------------------------------
>> static void
>> Noddy_dealloc(Noddy* self)
>> {
>>    delete p;
>>    self->ob_type->tp_free((PyObject*)self);
>> }
>>
>> And I found it's strange that it didn't call dealloc when there is no
>> reference.

And you set the tp_dealloc field in the type structure to Noddy_dealloc,
did you?

>> ex:
>> a = Noddy()
>> b = a
>> del a
>> del b
>> # i think there is no ref to the object, and it should call dealloc
>> but it didn't call!!!

You can use sys.getrefcount(a) to check how many references it has.
Remember that it returns one more than the value you expect (because the
function itself holds a temporary reference to its argument)

> Hi Shen,
> I'm no expert on Python memory management, but since no once else has  
> answered your question I'll tell you what I *think* is happening.
>
> Python doesn't delete objects as soon as they're dereferenced.

Nope. CPython *does* destroy objects as soon as their reference count
reaches zero. It does not rely on garbage collection for that.

> It merely marks them as safe for garbage collection (GC). If GC never  
> happens (and it might not in a small test program), your dealloc  
> function won't run.

The garbage collector is only used to recover memory from object cycles
(in the CPython implementation; Jython *does* use garbage collection for
"normal" object destruction too)

> Now some more knowledgeable person will probably correct me. =)

And now some more knowledgeable person will probably correct me. =)

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:48 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:48 -0300
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
	<9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>
	<h2htjt$t6e$00$1@news.t-online.com>
	<7c8e96a1-cbb2-4036-9aa1-1ecdfd84cca8@j32g2000yqh.googlegroups.com>
Message-ID: <op.uwgwwsx8x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 07:55:42 -0300, Pedram <pm567426 at gmail.com> escribi?:
> On Jul 2, 1:11?pm, Peter Otten <__pete... at web.de> wrote:

>> [snip explanation of strange pointer manipulations in the C code of the  
>> integer type]

> Oh, I got it! What a wonderful implementation! :o

Well, I would not say it's "wonderful"...
The wonderful part is that all those nasty tricks are only there, hidden
  from us poor mortals, so we can focus on writing nice and elegant Python
code instead :)

-- 
Gabriel Genellina



From http  Thu Jul  2 21:30:07 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 18:30:07 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
Message-ID: <7x4otu1rkw.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> This code is part of a delete() method for a binary tree
> implementation. "None" is used to simulate a NULL pointer. In the case
> where both children are non-None the code goes on to handle that.
> 
> None is a "unitary" or "singleton" value, so "is" is the right
> comparison operator to use with it, at least in this "imitation
> pointer" usage.

Yes, but the concept of null pointers is considered kludgy these days.
One alternative is to represent an empty node as an empty list [], and
a node with value x as the 1-element list [x].  That incurs some
storage overhead, but all the case by case checking in your comparison
function goes away:

   return (self.higher + self.lower)[:1]

> I've never used dis.dis() to check the bytecodes, but I wouldn't be
> surprised to find that the compiler generated the same bytecode
> whether you explicitly state the return or comment it out.)

I really wouldn't worry about this.  Python is so slow no matter what
you do, that 1 more no-op bytecode won't matter.

> Last but not least, the logic may seem backwards but it's actually
> correct. If you check for non-None (NULL) -ness and return the thing
> you checked, rather than checking for None-ness and returning the
> other, the case where both are non-None is not handled correctly.

The code you posted didn't return anything if both values were non-None.

As for checking for None-ness vs. non-None-ness, sure, the two are
logically equivalent, but I think checking for non-None expresses the
algorithm more clearly.

> FWIW, here's the BinaryTree class, ...
>     A Binary Tree implementation. Provides:
>         get(key) - Return item for key or None.

I'm sorry but I find that class rather ugly.  The code would be a lot
smaller and have fewer corner cases with a different data
representation.


From rylesny at gmail.com  Thu Jul  2 22:10:18 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 19:10:18 -0700 (PDT)
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com> 
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net> 
	<mailman.2478.1246529340.8015.python-list@python.org>
Message-ID: <1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>

On Jul 2, 6:10?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> En Wed, 01 Jul 2009 12:49:31 -0300, Scott David Daniels ?
> <Scott.Dani... at acm.org> escribi?:
> > These loops work well with the two-argument version of iter,
> > which is easy to forget, but quite useful to have in your bag
> > of tricks:
>
> > ? ? ?def convert(in_queue, out_queue):
> > ? ? ? ? ?for row in iter(in_queue.get, None):
> > ? ? ? ? ? ? ?# ... convert row
> > ? ? ? ? ? ? ?out_queue.put(converted_line)
>
> Yep, I always forget about that variant of iter() -- very handy!

Yes, at first glance using iter() here seems quite elegant and clever.
You might even pat yourself on the back, or treat yourself to an ice
cream cone, as I once did. There is one subtle distinction, however.
Please allow me to demonstrate.

>>> import Queue
>>>
>>> queue = Queue.Queue()
>>>
>>> queue.put(1)
>>> queue.put("la la la")
>>> queue.put(None)
>>>
>>> list(iter(queue.get, None))
[1, 'la la la']
>>>
>>> # Cool, it really works! I'm going to change all my old code to use this... new and *improved*
...
>>> # And then one day your user inevitably does something like this.
...
>>> class A(object):
...     def __init__(self, value):
...         self.value = value
...
...     def __eq__(self, other):
...         return self.value == other.value
...
>>> queue.put(A(1))
>>> queue.put(None)
>>>
>>> # And then this happens inside your 'generic' code (which probably even passed your unit tests).
...
>>> list(iter(queue.get, None))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 5, in __eq__
AttributeError: 'NoneType' object has no attribute 'value'
>>>
>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which iter() will do. Sorry guys!

Please don't let this happen to you too ;)


From http  Thu Jul  2 22:20:03 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 19:20:03 -0700
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
Message-ID: <7xfxdev770.fsf@ruckus.brouhaha.com>

ryles <rylesny at gmail.com> writes:
> >>> # Oh... yeah. I really *did* want 'is None' and not '== None'
> >>> which iter() will do. Sorry guys!
> 
> Please don't let this happen to you too ;)

None is a perfectly good value to put onto a queue.  I prefer
using a unique sentinel to mark the end of the stream:

   sentinel = object()


From rylesny at gmail.com  Thu Jul  2 22:23:54 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 19:23:54 -0700 (PDT)
Subject: What are the limitations of cStringIO.StringIO() ?
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com> 
	<mailman.2455.1246494464.8015.python-list@python.org>
Message-ID: <5354b682-1f7e-4274-96e6-b51a3556e931@h11g2000yqb.googlegroups.com>

This reminds me. Would anyone object to adding a sentence to
http://docs.python.org/library/stringio.html#module-cStringIO just to
mention that attributes cannot be added to a cStringIO, like such:

% import cStringIO, StringIO
% StringIO.StringIO().value = 1
% cStringIO.StringIO().value = 1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'cStringIO.StringO' object has no attribute 'value'


From bearophileHUGS at lycos.com  Thu Jul  2 22:34:50 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 2 Jul 2009 19:34:50 -0700 (PDT)
Subject: Is Psyco good for Python 2.6.1?
References: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
Message-ID: <c8b3d84a-5975-4912-a757-b613c2973a63@j32g2000yqh.googlegroups.com>

Russ P.:

Python works well to me on Python 2.6+, on Windows. You can find a
compiled version too, around.

Bye,
bearophile



From davea at ieee.org  Thu Jul  2 22:35:59 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 02 Jul 2009 22:35:59 -0400
Subject: stringio+tarfile
In-Reply-To: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <4A4D6E8F.1000506@ieee.org>

superpollo wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">why the 
> following does not work? can you help me correct (if possible)?
>
>       1 import tarfile
>       2 import StringIO
>       3 sf1 = StringIO.StringIO("one\n")
>       4 sf2 = StringIO.StringIO("two\n")
>       5 tf = StringIO.StringIO()
>       6 tar = tarfile.open(tf , "w")
>       7 for name in [sf1 , sf2]:
>       8     tar.add(name)
>       9 print tf
>      10 sf1.close()
>      11 sf2.close()
>      12 tf.close()
>      13 tar.close()
>
> tia
>
> </div>
>
Couldn't you have given a clue as to what doesn't work?   What version 
of Python are you using, and on what platform?  Do you get an error 
message, or are the results unreasonable? Details please.

First problem I see is all those numbers before the lines.  That's not 
valid python.

Assuming that was a transcription error, we get to some other problems.

tarfile.open() first argument is a filename, and you're passing it a 
Stringio object.  Not the same at all.  Fortunately, the Stringio should 
work as the third parameter, so you can change this line to
   tarfile.open(None, "w", tf)


Similarly tar.add() takes a filename as a parameter, and you're trying 
to pass another Stringio.  That's not a possible argument to the add() 
method at all.  Try tar.addfile()

I stopped at this point.  Maybe somebody else can help, after you fill 
in a few details.



From sajmikins at gmail.com  Thu Jul  2 22:52:10 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 22:52:10 -0400
Subject: What are the limitations of cStringIO.StringIO() ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
Message-ID: <50f98a4c0907021952y50bea866heb69ed4cff52d590@mail.gmail.com>

On Wed, Jul 1, 2009 at 7:48 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
> Hi,
>
> I think I'm up against a limitation in cStringIO.StringIO(), but could not
> find any clues on the web, especially not in
> http://docs.python.org/library/stringio.html.
>
> What I have is the following function:
>
> ??? def concatenate_files(self,filename_array):
> ??????? import types
>
> ??????? f = cStringIO.StringIO()
> ??????? for filename in filename_array:
> ??????????? log_stream = LogStream(filename)
> ??????????? if not isinstance(log_stream, types.NoneType):
> ??????????????? try:
> ??????????????????? string_ = log_stream.input_file.read()
> ??????????????? except AttributeError, e:
> ??????????????????????? sys.stderr.write("AttributeError: "+str(e)+"\n")
> ??????????????????????? sys.stderr.write("log_stream:
> "+str(log_stream)+"\n")
> ??????????? else:
> ??????????????? return(None)
>
> ??????????? f.write(string_)
> ??????? return (f)
>
> And, when the list of files?- in filename_array - is pointing to long/large
> enough files, I get the exception:
>
> Traceback (most recent call last):
> ? File "svm_ts_tool_in_progress.py", line 244, in OnSelectCell
> ??? self.InspectorViewController(row,col)
> ? File "svm_ts_tool_in_progress.py", line 1216, in InspectorViewController
> ??? self.InspectorePaneGetRecords(self.req_table, rec)
> ? File "svm_ts_tool_in_progress.py", line 1315, in InspectorePaneGetRecords
> ??? log_stream =
> ConcatenatedLogStream(self.events_dict[req_table]["db_dict"].keys())
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 31, in
> __init__
> ??? self.input_file = self.concatenate_files(filename_array)
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 47, in
> concatenate_files
> ??? string_ = log_stream.input_file.read()
> MemoryError
>
> Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
> Could you suggest a better way to create a string that contains the
> concatenation of several big files ?
>
> Thanks,
> Ron.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>

MemoryError means you're out of memory.  Try using the operating
system commands for file concatenation, i.e. "cat" on *nix, dunno how
on windows.  Or just do whatever it is you're doing in a different way
that doesn't require having all the data in memory at once.

Also, this:

not isinstance(log_stream, types.NoneType)

should just be this:

log_stream is not None

and return is not a function, leave out the ()'s around the expression
you're returning, and if you're returning None, you can leave out the
None as it is the default return value anyway.

Generally speaking don't do module imports in functions.


From benjamin at python.org  Thu Jul  2 22:54:31 2009
From: benjamin at python.org (Benjamin Peterson)
Date: Fri, 3 Jul 2009 02:54:31 +0000 (UTC)
Subject: What are the limitations of cStringIO.StringIO() ?
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
	<mailman.2455.1246494464.8015.python-list@python.org>
	<5354b682-1f7e-4274-96e6-b51a3556e931@h11g2000yqb.googlegroups.com>
Message-ID: <loom.20090703T025406-577@post.gmane.org>

ryles <rylesny <at> gmail.com> writes:

> 
> This reminds me. Would anyone object to adding a sentence to
> http://docs.python.org/library/stringio.html#module-cStringIO just to
> mention that attributes cannot be added to a cStringIO, like such:

That's true of almost all types that are implemented in C.






From rylesny at gmail.com  Thu Jul  2 22:55:19 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 19:55:19 -0700 (PDT)
Subject: Adding an object to the global namespace through " f_globals" is 
	that allowed ?
References: <4A4BC22D.70502@gmail.com>
	<mailman.2467.1246512323.8015.python-list@python.org>
Message-ID: <4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>

On Jul 2, 1:25 am, Terry Reedy <tjre... at udel.edu> wrote:
> > The next statement works,
> > but I'm not sure if it will have any dramatical side effects,
> > other than overruling a possible object with the name A
>
> > def some_function ( ...) :
> >      A = object ( ...)
> >      sys._getframe(1).f_globals [ Name ] = A
>
> global name
> name = A
>
> or is name is a string var
> globals()[name] = A

It wasn't explicit, but I think Stef meant that the global should be
added to the caller's environment, which was the reason for
sys._getframe().

Is this environment only intended for interactive use? I wonder if you
might just set things up
in a PYTHONSTARTUP script instead.


From schickb at gmail.com  Thu Jul  2 22:56:50 2009
From: schickb at gmail.com (schickb)
Date: Thu, 2 Jul 2009 19:56:50 -0700 (PDT)
Subject: Sequence splitting
Message-ID: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>

I have fairly often found the need to split a sequence into two groups
based on a function result. Much like the existing filter function,
but returning a tuple of true, false sequences. In Python, something
like:

def split(seq, func=None):
    if func is None:
        func = bool
    t, f = [], []
    for item in seq:
        if func(item):
            t.append(item)
        else:
            f.append(item)
    return (t, f)

The discussion linked to below has various approaches for doing this
now, but most traverse the sequence twice and many don't apply a
function to spit the sequence.
http://stackoverflow.com/questions/949098/python-split-a-list-based-on-a-condition

Is there any interest in a C implementation of this? Seems too trivial
to write a PEP, so I'm just trying to measure interest before diving
in. This wouldn't really belong in intertool. Would it be best
implemented as a top level built-in?

-Brad


From alan.isaac at gmail.com  Thu Jul  2 22:59:51 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 02:59:51 GMT
Subject: Python 3.0 (pinin' for the fjords)
In-Reply-To: <mailman.2526.1246576243.8015.python-list@python.org>
References: <mailman.2526.1246576243.8015.python-list@python.org>
Message-ID: <Hue3m.534$P5.391@nwrddc02.gnilink.net>

Using the 3.1 Windows installer, I chose that I did not
want the extensions registered, and the installer
unregistered the .py and .pyw extensions (which I had wanted
to keep associated with Python 2.6).

Is this intentional?

Alan Isaac

PS I already fixed the problem.  My question
is about intent.


From rylesny at gmail.com  Thu Jul  2 23:09:25 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 20:09:25 -0700 (PDT)
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com> 
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net> 
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
Message-ID: <c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>

On Jul 2, 10:20?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> ryles <ryle... at gmail.com> writes:
> > >>> # Oh... yeah. I really *did* want 'is None' and not '== None'
> > >>> which iter() will do. Sorry guys!
>
> > Please don't let this happen to you too ;)
>
> None is a perfectly good value to put onto a queue. ?I prefer
> using a unique sentinel to mark the end of the stream:
>
> ? ?sentinel = object()

I agree, this is cleaner than None. We're still in the same boat,
though, regarding iter(). Either it's 'item == None' or 'item == object
()', and depending on the type, __eq__ can introduce some avoidable
risk.

FWIW, even object() has its disadvantages. Namely, it doesn't work for
multiprocessing.Queue which pickles and unpickles, thus giving you a
new object. One way to deal with this is to define a "Stopper" class
and type check objects taken from the queue. This is not news to
anyone who's worked with multiprocessing.Queue, though.


From tn.pablo at gmail.com  Thu Jul  2 23:10:14 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 2 Jul 2009 22:10:14 -0500
Subject: Sequence splitting
In-Reply-To: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
Message-ID: <fdd00b510907022010g34958774p77f68c4cc35b19c9@mail.gmail.com>

On Thu, Jul 2, 2009 at 21:56, schickb<schickb at gmail.com> wrote:
> I have fairly often found the need to split a sequence into two groups
> based on a function result. Much like the existing filter function,
> but returning a tuple of true, false sequences. In Python, something
> like:
>
> def split(seq, func=None):
> ? ?if func is None:
> ? ? ? ?func = bool
> ? ?t, f = [], []
> ? ?for item in seq:
> ? ? ? ?if func(item):
> ? ? ? ? ? ?t.append(item)
> ? ? ? ?else:
> ? ? ? ? ? ?f.append(item)
> ? ?return (t, f)
>
> The discussion linked to below has various approaches for doing this
> now, but most traverse the sequence twice and many don't apply a
> function to spit the sequence.
> http://stackoverflow.com/questions/949098/python-split-a-list-based-on-a-condition
>
> Is there any interest in a C implementation of this? Seems too trivial
> to write a PEP, so I'm just trying to measure interest before diving
> in. This wouldn't really belong in intertool. Would it be best
> implemented as a top level built-in?
>
> -Brad
> --
> http://mail.python.org/mailman/listinfo/python-list
>

This sounds like it belongs to the python-ideas list.  I suggest
posting there for better feedback, since the core developers check
that list more often than this one.


-- 
Pablo Torres N.


From http  Thu Jul  2 23:14:24 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 20:14:24 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
Message-ID: <7xzlbm5ugf.fsf@ruckus.brouhaha.com>

schickb <schickb at gmail.com> writes:
> def split(seq, func=None):
>     if func is None:
>         func = bool
>     t, f = [], []
>     for item in seq:
>         if func(item):
>             t.append(item)
>         else:
>             f.append(item)
>     return (t, f)

untested:

   def split(seq, func=bool):
      xs = zip(seq, itertools.imap(func, seq))
      t = list(x for (x,y) in xs if y)
      f = list(x for (x,y) in xs if not y)
      return (t, f)


From http  Thu Jul  2 23:15:40 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 20:15:40 -0700
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
Message-ID: <7xvdma5ueb.fsf@ruckus.brouhaha.com>

ryles <rylesny at gmail.com> writes:
> > ? ?sentinel = object()
> 
> I agree, this is cleaner than None. We're still in the same boat,
> though, regarding iter(). Either it's 'item == None' or 'item == object ()'

Use "item is sentinel".  


From tn.pablo at gmail.com  Thu Jul  2 23:17:32 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 2 Jul 2009 20:17:32 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
Message-ID: <3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>

On Jul 2, 9:56?pm, schickb <schi... at gmail.com> wrote:
> I have fairly often found the need to split a sequence into two groups
> based on a function result. Much like the existing filter function,
> but returning a tuple of true, false sequences. In Python, something
> like:
>
> def split(seq, func=None):
> ? ? if func is None:
> ? ? ? ? func = bool
> ? ? t, f = [], []
> ? ? for item in seq:
> ? ? ? ? if func(item):
> ? ? ? ? ? ? t.append(item)
> ? ? ? ? else:
> ? ? ? ? ? ? f.append(item)
> ? ? return (t, f)
>
> The discussion linked to below has various approaches for doing this
> now, but most traverse the sequence twice and many don't apply a
> function to spit the sequence.http://stackoverflow.com/questions/949098/python-split-a-list-based-o...
>
> Is there any interest in a C implementation of this? Seems too trivial
> to write a PEP, so I'm just trying to measure interest before diving
> in. This wouldn't really belong in intertool. Would it be best
> implemented as a top level built-in?
>
> -Brad

This sounds like it belongs to the python-ideas list.  I suggest
posting there for better feedback, since the core developers check
that list more often than this one.



From philip at semanchuk.com  Thu Jul  2 23:17:35 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 2 Jul 2009 23:17:35 -0400
Subject: dealloc function in python extend c module
In-Reply-To: <op.uwgv3ywwx6zn5v@lepton.softlabbsas.com.ar>
References: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
	<8599A253-D2C9-4EE4-AF4F-AEF658BA2033@semanchuk.com>
	<op.uwgv3ywwx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <AE97376F-ED7D-48D8-9543-4EB109C673AC@semanchuk.com>


On Jul 2, 2009, at 9:28 PM, Gabriel Genellina wrote:

> En Thu, 02 Jul 2009 14:22:53 -0300, Philip Semanchuk
> <philip at semanchuk.com> escribi?:
>>
>> Hi Shen,
>> I'm no expert on Python memory management, but since no once else  
>> has answered your question I'll tell you what I *think* is happening.
>>
>> Python doesn't delete objects as soon as they're dereferenced.
>
> Nope. CPython *does* destroy objects as soon as their reference count
> reaches zero. It does not rely on garbage collection for that.
>
>> It merely marks them as safe for garbage collection (GC). If GC  
>> never happens (and it might not in a small test program), your  
>> dealloc function won't run.
>
> The garbage collector is only used to recover memory from object  
> cycles
> (in the CPython implementation; Jython *does* use garbage collection  
> for
> "normal" object destruction too)
>
>> Now some more knowledgeable person will probably correct me. =)

Wow, that last part was the only part I got right. =) Thanks for  
straightening me out, Gabriel.





From gagsl-py2 at yahoo.com.ar  Thu Jul  2 23:47:54 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 03 Jul 2009 00:47:54 -0300
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
	<7xvdma5ueb.fsf@ruckus.brouhaha.com>
Message-ID: <op.uwg3h4pdx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 00:15:40 -0300, <//phr.cx at nospam.invalid>> escribi?:

> ryles <rylesny at gmail.com> writes:
>> > ? ?sentinel = object()
>>
>> I agree, this is cleaner than None. We're still in the same boat,
>> though, regarding iter(). Either it's 'item == None' or 'item == object  
>> ()'
>
> Use "item is sentinel".

We're talking about the iter() builtin behavior, and that uses ==  
internally.

It could have used an identity test, and that would be better for this  
specific case. But then iter(somefile.read, '') wouldn't work. A  
compromise solution is required; since one can customize the equality test  
but not an identity test, the former has a small advantage. (I don't know  
if this was the actual reason, or even if this really was a concious  
decision, but that's why *I* would choose == to test against the sentinel  
value).

-- 
Gabriel Genellina



From sajmikins at gmail.com  Thu Jul  2 23:54:18 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 20:54:18 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
Message-ID: <a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>

On Jul 2, 9:30?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> writes:
> > This code is part of a delete() method for a binary tree
> > implementation. "None" is used to simulate a NULL pointer. In the case
> > where both children are non-None the code goes on to handle that.
>
> > None is a "unitary" or "singleton" value, so "is" is the right
> > comparison operator to use with it, at least in this "imitation
> > pointer" usage.
>
> Yes, but the concept of null pointers is considered kludgy these days.

Seriously? "kludgy"?  (I really AM getting old.)

Well I wouldn't know, I've been fortunate enough to program mostly in
python for over half a decade now and None and 0 are as close as I've
gotten to NULL in a long time.

> One alternative is to represent an empty node as an empty list [], and
> a node with value x as the 1-element list [x]. ?That incurs some
> storage overhead, but all the case by case checking in your comparison
> function goes away:
>
> ? ?return (self.higher + self.lower)[:1]

Heh, program LISP much? :]

That sounds very interesting, but I'm only writing a BTree to then use
it to play with "persistent data structures" and the models I'm using
are based on pointer code.  I wouldn't want to try to re-implement
them on top of a different "architecture", at least not at first.

> > I've never used dis.dis() to check the bytecodes, but I wouldn't be
> > surprised to find that the compiler generated the same bytecode
> > whether you explicitly state the return or comment it out.)
>
> I really wouldn't worry about this. ?Python is so slow no matter what
> you do, that 1 more no-op bytecode won't matter.

I'm not worried about it at all. In fact, I'm pretty sure the compiler
handles it for me as well as I could want or expect it to.

"A Computer's Perspective on Moore's Law: Humans are getting more
expensive at an exponential rate." - Mark Miller
http://www.caplet.com/adages.html

Python may be slow to execute but it's fast to write. (And write
well.)  ;]

> > Last but not least, the logic may seem backwards but it's actually
> > correct. If you check for non-None (NULL) -ness and return the thing
> > you checked, rather than checking for None-ness and returning the
> > other, the case where both are non-None is not handled correctly.
>
> The code you posted didn't return anything if both values were non-None.

Yep, it was just a snippet, just the part I wanted feedback on.

> As for checking for None-ness vs. non-None-ness, sure, the two are
> logically equivalent, but I think checking for non-None expresses the
> algorithm more clearly.

In this particular case it's somewhat more elegant (IMO) to check "is
None".

> > FWIW, here's the BinaryTree class, ...
> > ? ? A Binary Tree implementation. Provides:
> > ? ? ? ? get(key) - Return item for key or None.
>
> I'm sorry but I find that class rather ugly. ?The code would be a lot
> smaller and have fewer corner cases with a different data
> representation.

Um, thanks?  Seriously though, care to put your money where your mouth
is? I'd be interested to see a BTree implemented as you indicated
above.

Pointer code in python is silly in general, since you're only
imitating real pointers with attributes (i.e. instance dicts) anyway.
As I said above, I'm faking it with python to explore persistent data
structures and the models I've found so far are pointer-based.  I'm
sure there are better (i.e. faster) ways to get the same (or
sufficiently similar) behavior in a more "pythonic" fashion. (for
example, to maintain a sorted sequence under insertion I'd use a list
and the bisect module, and so on.)

Reminds me, a few years back I implemented Knuth's "Dancing Links"
algorithm in python for a Sudoku solver.  It uses a kind of grid of
doubly-linked lists to store information about the search space and to
traverse that space to resolve an answer.  The algorithm takes
advantage of the fact that allocated nodes persisted in memory even
when completely unlinked from the "surrounding" lists.  You unlinked
and re-linked the nodes/lists in a certain pattern to search and
backtrack the search space.  It's more than I can explain here. Really
elegant algorithm.

The point is in python you had to put ALL the nodes into a storage
structure just to prevent them disappearing while unlinked from the
"head" of the grid.

Regards,
~Simon


From schickb at gmail.com  Thu Jul  2 23:55:12 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 20:55:12 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
Message-ID: <08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>

On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> schickb <schi... at gmail.com> writes:
> > def split(seq, func=None):
> > ? ? if func is None:
> > ? ? ? ? func = bool
> > ? ? t, f = [], []
> > ? ? for item in seq:
> > ? ? ? ? if func(item):
> > ? ? ? ? ? ? t.append(item)
> > ? ? ? ? else:
> > ? ? ? ? ? ? f.append(item)
> > ? ? return (t, f)
>
> untested:
>
> ? ?def split(seq, func=bool):
> ? ? ? xs = zip(seq, itertools.imap(func, seq))
> ? ? ? t = list(x for (x,y) in xs if y)
> ? ? ? f = list(x for (x,y) in xs if not y)
> ? ? ? return (t, f)

In my testing that is 3.5x slower than the original solution (and less
clear imo). I fixed my version to take a bool default. Either way, I'm
not really looking for additional ways to do this in Python unless
I've totally missed something. What I am considering is writing it in
C, much like filter.

-Brad


From http  Thu Jul  2 23:55:12 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 20:55:12 -0700
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
	<7xvdma5ueb.fsf@ruckus.brouhaha.com>
	<mailman.2538.1246592805.8015.python-list@python.org>
Message-ID: <7xhbxu4dzz.fsf@ruckus.brouhaha.com>

"Gabriel Genellina" <gagsl-py2 at yahoo.com.ar> writes:
> We're talking about the iter() builtin behavior, and that uses ==
> internally.

Oh, I see.  Drat.

> It could have used an identity test, and that would be better for this
> specific case. But then iter(somefile.read, '') wouldn't work.

Yeah, it should allow supplying a predicate instead of using == on
a value.  How about (untested):

   from itertools import *
   ...
   for row in takewhile(lambda x: x is sentinel,
                         starmap(in_queue.get, repeat(()))): 
      ...


From schickb at gmail.com  Thu Jul  2 23:56:03 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 20:56:03 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
Message-ID: <d72a0e75-5dc4-4c08-8ae2-5b5dce11d531@m7g2000prd.googlegroups.com>

On Jul 2, 8:17?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
> On Jul 2, 9:56?pm, schickb <schi... at gmail.com> wrote:
>
> > I have fairly often found the need to split a sequence into two groups
> > based on a function result.
>
> This sounds like it belongs to the python-ideas list. ?I suggest
> posting there for better feedback, since the core developers check
> that list more often than this one.

Thanks, I didn't know about that list.


From rylesny at gmail.com  Thu Jul  2 23:56:52 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 20:56:52 -0700 (PDT)
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
Message-ID: <c9e58a82-d371-43bb-b6d5-334e8aa54041@s9g2000yqd.googlegroups.com>

On Jul 2, 11:09?am, masher <vertesp... at gmail.com> wrote:
> My questions, then, is: Is there a more elegant/pythonic way of doing
> what I am trying to do with the current Pool class?

Another thing you might try is to subclass Pool and add an apply_async
() wrapper which would wait for _taskqueue.qsize() to reach the
desired size. You would probably do this wait in a loop with a small
sleep. This approach would avoid needing a second Queue, but you would
also add some delay to your producer due to the sleep (something
you're not currently worried about). The minimum sleep may be
something like 1 ms (it's really system dependent), but the time it
takes for a thread blocked on a mutex to wake up is often more on the
order of microseconds, which you have with your blocking queue.

I doubt this offers you much satisfaction, though.

> If the verdict is no, I'll be happy to file a bug report.

Yeah, I think it's a worth a try.


From http  Fri Jul  3 00:08:02 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 21:08:02 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
Message-ID: <7xhbxu4del.fsf@ruckus.brouhaha.com>

Brad <schickb at gmail.com> writes:

> On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> > schickb <schi... at gmail.com> writes:
> > > def split(seq, func=None):
> > > ? ? if func is None:
> > > ? ? ? ? func = bool
> > > ? ? t, f = [], []
> > > ? ? for item in seq:
> > > ? ? ? ? if func(item):
> > > ? ? ? ? ? ? t.append(item)
> > > ? ? ? ? else:
> > > ? ? ? ? ? ? f.append(item)
> > > ? ? return (t, f)
> >
> > untested:
> >
> > ? ?def split(seq, func=bool):
> > ? ? ? xs = zip(seq, itertools.imap(func, seq))
> > ? ? ? t = list(x for (x,y) in xs if y)
> > ? ? ? f = list(x for (x,y) in xs if not y)
> > ? ? ? return (t, f)
> 
> In my testing that is 3.5x slower than the original solution (and less
> clear imo). I fixed my version to take a bool default. Either way, I'm
> not really looking for additional ways to do this in Python unless
> I've totally missed something. What I am considering is writing it in
> C, much like filter.

I'm a little skeptical that the C version will help much, if it's
evaluating a python function at every list element.  Here's a variant
of your version:

 def split(seq, func=bool):
 ? ? t, f = [], []
     ta, fa = t.append, f.append
 ? ? for item in seq:
         (ta if func(item) else fa)(item)
 ? ? return (t, f)

This avoids some dict lookups and copying.  I wonder if that helps
significantly.


From rylesny at gmail.com  Fri Jul  3 00:13:19 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 21:13:19 -0700 (PDT)
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com> 
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net> 
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
	<7xvdma5ueb.fsf@ruckus.brouhaha.com>
	<mailman.2538.1246592805.8015.python-list@python.org> 
	<7xhbxu4dzz.fsf@ruckus.brouhaha.com>
Message-ID: <34271171-ba63-43bb-b79c-83c036453007@c9g2000yqm.googlegroups.com>

On Jul 2, 11:55?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Yeah, it should allow supplying a predicate instead of using == on
> a value. ?How about (untested):
>
> ? ?from itertools import *
> ? ?...
> ? ?for row in takewhile(lambda x: x is sentinel,
> ? ? ? ? ? ? ? ? ? ? ? ? ?starmap(in_queue.get, repeat(()))):
> ? ? ? ...

Yeah, it's a small recipe I'm sure a lot of others have written as
well. My old version:

def iterwhile(callable_, predicate):
    """ Like iter() but with a predicate instead of a sentinel. """
    return itertools.takewhile(predicate, repeatfunc(callable_))

where repeatfunc is as defined here:

http://docs.python.org/library/itertools.html#recipes

I wish all of these little recipes made their way into itertools or a
like module; itertools seems a bit tightly guarded.


From schickb at gmail.com  Fri Jul  3 00:34:21 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 21:34:21 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
Message-ID: <c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>

On Jul 2, 9:08?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Brad <schi... at gmail.com> writes:
> > On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> > > schickb <schi... at gmail.com> writes:
> > > > def split(seq, func=None):
> > > > ? ? if func is None:
> > > > ? ? ? ? func = bool
> > > > ? ? t, f = [], []
> > > > ? ? for item in seq:
> > > > ? ? ? ? if func(item):
> > > > ? ? ? ? ? ? t.append(item)
> > > > ? ? ? ? else:
> > > > ? ? ? ? ? ? f.append(item)
> > > > ? ? return (t, f)
>
> > > untested:
>
> > > ? ?def split(seq, func=bool):
> > > ? ? ? xs = zip(seq, itertools.imap(func, seq))
> > > ? ? ? t = list(x for (x,y) in xs if y)
> > > ? ? ? f = list(x for (x,y) in xs if not y)
> > > ? ? ? return (t, f)
>
> > In my testing that is 3.5x slower than the original solution (and less
> > clear imo). I fixed my version to take a bool default. Either way, I'm
> > not really looking for additional ways to do this in Python unless
> > I've totally missed something. What I am considering is writing it in
> > C, much like filter.
>
> I'm a little skeptical that the C version will help much, if it's
> evaluating a python function at every list element. ?

Perhaps true, but it would be a nice convenience (for me) as a built-
in written in either Python or C. Although the default case of a bool
function would surely be faster.

> Here's a variant of your version:
>
> ?def split(seq, func=bool):
> ?? ? t, f = [], []
> ? ? ?ta, fa = t.append, f.append
> ?? ? for item in seq:
> ? ? ? ? ?(ta if func(item) else fa)(item)
> ?? ? return (t, f)
>
> This avoids some dict lookups and copying. ?I wonder if that helps
> significantly.

Faster, but in tests of a few short sequences only 1% so.

-Brad


From ldo at geek-central.gen.new_zealand  Fri Jul  3 00:39:46 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Fri, 03 Jul 2009 16:39:46 +1200
Subject: Config files with different types
References: <mailman.2506.1246557392.8015.python-list@python.org>
Message-ID: <h2k22j$i70$1@lust.ihug.co.nz>

In message <mailman.2506.1246557392.8015.python-list at python.org>, Zach 
Hobesh wrote:

> I want to be able to look at the value and determine what type it
> SHOULD be.  Right now, configs['overwrite'] = 'true' (a string) when
> it might be more useful as a boolean.

Typically the type should be what you expect, not what is given. For 
example, it doesn't make sense for your configs["overwrite"] setting to be 
"red", does it?

A reasonable solution might be to have a table of expected types for each 
config item keyword, e.g.

    configs_types = \
        {
           ...
           "overwrite" : lambda x : x[0] not in set("nNfF"),
           ...
        }

Then you can just do something like

    configs[keyword] = configs_types[keyword](configs[keyword])

with appropriate trapping of ValueError exceptions.



From tn.pablo at gmail.com  Fri Jul  3 00:40:13 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 2 Jul 2009 23:40:13 -0500
Subject: Sequence splitting
In-Reply-To: <c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
Message-ID: <fdd00b510907022140g299b4616p64133a2e49716866@mail.gmail.com>

On Thu, Jul 2, 2009 at 23:34, Brad<schickb at gmail.com> wrote:
> On Jul 2, 9:08?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>> Brad <schi... at gmail.com> writes:
>> > On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>> > > schickb <schi... at gmail.com> writes:
>> > > > def split(seq, func=None):
>> > > > ? ? if func is None:
>> > > > ? ? ? ? func = bool
>> > > > ? ? t, f = [], []
>> > > > ? ? for item in seq:
>> > > > ? ? ? ? if func(item):
>> > > > ? ? ? ? ? ? t.append(item)
>> > > > ? ? ? ? else:
>> > > > ? ? ? ? ? ? f.append(item)
>> > > > ? ? return (t, f)
>>
>> > > untested:
>>
>> > > ? ?def split(seq, func=bool):
>> > > ? ? ? xs = zip(seq, itertools.imap(func, seq))
>> > > ? ? ? t = list(x for (x,y) in xs if y)
>> > > ? ? ? f = list(x for (x,y) in xs if not y)
>> > > ? ? ? return (t, f)
>>
>> > In my testing that is 3.5x slower than the original solution (and less
>> > clear imo). I fixed my version to take a bool default. Either way, I'm
>> > not really looking for additional ways to do this in Python unless
>> > I've totally missed something. What I am considering is writing it in
>> > C, much like filter.
>>
>> I'm a little skeptical that the C version will help much, if it's
>> evaluating a python function at every list element.
>
> Perhaps true, but it would be a nice convenience (for me) as a built-
> in written in either Python or C. Although the default case of a bool
> function would surely be faster.
>
>> Here's a variant of your version:
>>
>> ?def split(seq, func=bool):
>> ?? ? t, f = [], []
>> ? ? ?ta, fa = t.append, f.append
>> ?? ? for item in seq:
>> ? ? ? ? ?(ta if func(item) else fa)(item)
>> ?? ? return (t, f)
>>
>> This avoids some dict lookups and copying. ?I wonder if that helps
>> significantly.
>
> Faster, but in tests of a few short sequences only 1% so.
>
> -Brad
> --
> http://mail.python.org/mailman/listinfo/python-list
>

If it is speed that we are after, it's my understanding that map and
filter are faster than iterating with the for statement (and also
faster than list comprehensions).  So here is a rewrite:

def split(seq, func=bool):
 	t = filter(func, seq)
 	f = filter(lambda x: not func(x), seq)
 	return list(t), list(f)

The lambda thing is kinda ugly, but I can't think of anything else.
Also, is it ok to return lists?  Py3k saw a lot of APIs changed to
return iterables instead of lists, so maybe my function should have
'return t, f' as it's last statement.


-- 
Pablo Torres N.


From sajmikins at gmail.com  Fri Jul  3 00:40:42 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 21:40:42 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
	<02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>
	<9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
Message-ID: <4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>

On Jul 2, 4:31?am, Tep <petshm... at googlemail.com> wrote:
> On 2 Jul., 10:25, Tep <petshm... at googlemail.com> wrote:
>
>
>
> > On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > someone wrote:
> > > > Hello,
>
> > > > how can I replace '?' sign from string? Or do split at that character?
> > > > Getting unicode error if I try to do it:
>
> > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > > > 1: ordinal not in range(128)
>
> > > > Thanks, Pet
>
> > > > script is # -*- coding: UTF-8 -*-
>
> > > It sounds like you're mixing bytestrings with Unicode strings. I can't
> > > be any more helpful because you haven't shown the code.
>
> > Oh, I'm sorry. Here it is
>
> > def cleanInput(input)
> > ? ? return input.replace('?', '')
>
> I also need:
>
> #input is html source code, I have problem with only this character
> #input = 'foo ? bar'
> #return should be foo
> def splitInput(input)
> ? ? parts = input.split(' ? ')
> ? ? return parts[0]
>
> Thanks!

Okay people want to help you but you must make it easy for us.

Post again with a small piece of code that is runnable as-is and that
causes the traceback you're talking about, AND post the complete
traceback too, as-is.

I just tried a bit of your code above in my interpreter here and it
worked fine:

|>>> data = 'foo ? bar'
|>>> data.split('?')
|['foo ', ' bar']
|>>> data = u'foo ? bar'
|>>> data.split(u'?')
|[u'foo ', u' bar']

Figure out the smallest piece of "html source code" that causes the
problem and include that with your next post.

HTH,
~Simon

You might also read this: http://catb.org/esr/faqs/smart-questions.html


From zookog at gmail.com  Fri Jul  3 00:48:10 2009
From: zookog at gmail.com (zooko)
Date: Thu, 2 Jul 2009 21:48:10 -0700 (PDT)
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org> 
	<h21mgt$oav$1@panix3.panix.com>
	<11eb0a6e-4e21-4a61-bf46-4221fd75dc8d@v15g2000prn.googlegroups.com>
	<006078f0$0$9721$c3e8da3@news.astraweb.com>
	<h22voe$b3k$1@panix3.panix.com> 
	<mailman.2170.1246042676.8015.python-list@python.org>
Message-ID: <f823bca6-e64c-47ea-97e6-a26b50732cb7@x6g2000prc.googlegroups.com>

Try PyJudy:

http://www.dalkescientific.com/Python/PyJudy.html


From http  Fri Jul  3 00:56:40 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 21:56:40 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
Message-ID: <7x3a9egy9j.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> > Yes, but the concept of null pointers is considered kludgy these days.
> Seriously? "kludgy"?  (I really AM getting old.)

  http://math.andrej.com/2009/04/11/on-programming-language-design/

discusses the issue (scroll down to "Undefined values" section).

> Well I wouldn't know, I've been fortunate enough to program mostly in
> python for over half a decade now and None and 0 are as close as I've
> gotten to NULL in a long time.

Right, and how many times have you had to debug

   AttributeError: 'NoneType' object has no attribute 'foo'

or the equivalent null pointer exceptions in Java, C, or whatever?
They are very common.  And the basic idea is that if you avoid using
null pointers in the first place, you'll get fewer accidental null
pointer exceptions.

> That sounds very interesting, but I'm only writing a BTree to then use
> it to play with "persistent data structures" 

But you have implemented a mutable tree.  If you want to write a
persistent one, then write a persistent one!  You also use a wishful
heuristic in the hope of keeping the tree balanced--if you want a
balanced tree, why not use one that's guaranteed to stay in balance?
AVL trees are pretty easy to implement; maybe you could try writing a
persistent one:

  http://en.wikipedia.org/wiki/AVL_tree

> In this particular case it's somewhat more elegant (IMO) to check "is
> None".

Well, I can't understand why that might be, but it's surely
subjective, so ok.

> > I'm sorry but I find that class rather ugly. ?The code would be a lot
> > smaller and have fewer corner cases with a different data representation.
> 
> Um, thanks?  Seriously though, care to put your money where your mouth
> is? I'd be interested to see a BTree implemented as you indicated above.

Er, I'm not trying to argue with you.  You asked for people's advice
and impressions, so I gave you some.  I don't feel like rewriting that
whole class, but I'll do a method or two, using [] to represent an
empty node.  (Hmm, actually changing the empty node representation did
less to shorten the code than just getting rid of a bunch of
duplication.  Really, I'd tend to look for a slightly different tree
structure which tried to avoid these issues).

Untested:

class BinaryTree:
    def __init__(self, key, value):
        self.key = key
        self.value = value
        self.higher = self.lower = []

    def get(self, key):
        if key == self.key:
            return self.value
        branch = self.lower if key < self.key else self.higher
        return branch.get(key) if branch else []

    def insert(self, key, value):
        def xinsert(xtree):  # xtree is either a tree or []
           if not xtree: xtree = BinaryTree(key, value)
           else: xtree.insert(key, value)
           return xtree

        if key == self.key:
            self.value = value
        elif key < self.key:
            self.lower = xinsert(self.lower)
        else:
            self.higher = xinsert(self.higher)

and so forth.


From http  Fri Jul  3 00:58:22 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 21:58:22 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
Message-ID: <7xy6r6fjm9.fsf@ruckus.brouhaha.com>

"Pablo Torres N." <tn.pablo at gmail.com> writes:
> def split(seq, func=bool):
>  	t = filter(func, seq)
>  	f = filter(lambda x: not func(x), seq)
>  	return list(t), list(f)

That is icky--you're calling func (which might be slow) twice instead
of once on every element of the seq.


From lie.1296 at gmail.com  Fri Jul  3 02:05:06 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:05:06 GMT
Subject: question of style
In-Reply-To: <VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
	<VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>
Message-ID: <mch3m.2328$ze1.1288@news-server.bigpond.net.au>

Tim Harig wrote:
>> Speaking only to the style issue, when I've wanted to do something like
>> that, I find:
>>        if self.higher is None is self.lower:
>> more readable, by making clear they are both being compared to a
>> constant, rather than compared to each other.
> 
> By comparing them to *any* constant with 'is' you end up with the same
> potential problems as to whether something with a value of None is actually
> None?  

Oh really? None is a Singleton and all None always point to the same
None object. And the fact that it is impossible to override `is`
operator is the reason for the "is None" idiom.

This does not happen with other objects though (except if you make them
as Singletons as well), and in case of immutable, you may get bugs due
to python's optimizing small integers.

> With equality operators
> everything is either the same or it isn't.   

How about:
class Fake(object):
    def __eq__(self, other):
        return True

we uses `is` when we want to make sure an object is really the same
object as another, not just an equivalent object.

I can start from the first
> variable and compare it to the second then to the third then ...  In the
> case of the inequality, I have to start with the first and compare it to
> all of the rest to make sure that none are the same.  Then I have to do the
> same for each with the remaining.  This is much more difficult to do in my
> head.  I requires much more thought, better left to a computer, when
> evaluating the expression for myself.  Therefore, equalites are quick and
> easy to keep straight whereas any inequalites are more error prone when
> trying to evaluate how a section of code will react under different
> circumstances.
> 
>> I do draw the line at two, though, and with three or more I'll
>> paren-up a list of parallel comparisons:
> 
> As long as everything is an equality, then I don't mind comparing to the
> end of an 70 column line.  Mixed types of equalities or inequalities
> require too many operations mentally evaluate safely.

Personally, I'd only chain inequality for something like this:
if 0 < x < 10:


From lie.1296 at gmail.com  Fri Jul  3 02:09:31 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:09:31 GMT
Subject: question of style
In-Reply-To: <529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
	<529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com>
Message-ID: <vgh3m.2329$ze1.1542@news-server.bigpond.net.au>

Simon Forman wrote:
> On Jul 2, 3:57 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>> Duncan Booth wrote:
>>> Simon Forman <sajmik... at gmail.com> wrote:
>>>> ...
>>>> if self.higher is self.lower is None: return
>>>> ...
>>> As a matter of style however I wouldn't use the shorthand to run two 'is'
>>> comparisons together, I'd write that out in full if it was actually needed
>>> here.
>> Speaking only to the style issue, when I've wanted to do something like
>> that, I find:
>>
>>        if self.higher is None is self.lower:
>>            ...
>>
>> more readable, by making clear they are both being compared to a
>> constant, rather than compared to each other.
> 
> I was going to do it that way for aesthetics if nothing else, but in
> this particular code "self.higher is self.lower" could only have been
> True if they were both None, so the final "is None" was redundant and
> I only included it as a "just-in-case" check in case someone someday
> used the code in such a way as to assign the same object (not None) to
> both self.higher and self.lower...  Totally pointless, I'm sorry to
> say.  I'm glad the whole line was redundant really.
> 

I say, you should keep the `is None` for readability and to safe guard
against immutable optimization and/or Singleton objects. Due to an
implementation detail, python does not guarantee that two immutable
object will return different objects; you have:

>>> a = 1
>>> b = 1
>>> a is b
True


From schickb at gmail.com  Fri Jul  3 02:31:18 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 23:31:18 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
Message-ID: <890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>

On Jul 2, 9:40?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>
> If it is speed that we are after, it's my understanding that map and
> filter are faster than iterating with the for statement (and also
> faster than list comprehensions). ?So here is a rewrite:
>
> def split(seq, func=bool):
> ? ? ? ? t = filter(func, seq)
> ? ? ? ? f = filter(lambda x: not func(x), seq)
> ? ? ? ? return list(t), list(f)
>

In my simple tests, that takes 1.8x as long as the original solution.
Better than the itertools solution, when "func" is short and fast. I
think the solution here would worse if func was more complex.

Either way, what I am still wondering is if people would find a built-
in implementation useful?

-Brad


From gagsl-py2 at yahoo.com.ar  Fri Jul  3 02:31:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 03 Jul 2009 03:31:42 -0300
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<7xy6r6fjm9.fsf@ruckus.brouhaha.com>
Message-ID: <op.uwha24x9x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 01:58:22 -0300, <//phr.cx at nospam.invalid>> escribi?:

> "Pablo Torres N." <tn.pablo at gmail.com> writes:
>> def split(seq, func=bool):
>>  	t = filter(func, seq)
>>  	f = filter(lambda x: not func(x), seq)
>>  	return list(t), list(f)
>
> That is icky--you're calling func (which might be slow) twice instead
> of once on every element of the seq.

In addition, this doesn't work if seq is an iterator instead of a sequence.

-- 
Gabriel Genellina



From lie.1296 at gmail.com  Fri Jul  3 02:33:03 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:33:03 GMT
Subject: question of style
In-Reply-To: <7x63eahp8z.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x63eahp8z.fsf@ruckus.brouhaha.com>
Message-ID: <zCh3m.2331$ze1.2286@news-server.bigpond.net.au>

Paul Rubin wrote:
> Generally, having a special
> value like None to denote a missing datum was considered standard
> practice a few decades ago, 

I guess in python, None as the missing datum idiom is still quite prevalent:

def cat_list(a=None, b=None):
    # poor man's list concatenation
    if a is None and b is None: return []
    if a is None: return b
    if b is None: return a
    return a + b


From schickb at gmail.com  Fri Jul  3 02:34:21 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 23:34:21 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
Message-ID: <e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>

On Jul 2, 8:17?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>
> This sounds like it belongs to the python-ideas list. ?I suggest
> posting there for better feedback, since the core developers check
> that list more often than this one.

I tried posting on python-ideas and received a "You are not allowed to
post to this mailing list" reply. Perhaps because I am posting through
Google groups? Or maybe one must be an approved member to post?

-Brad


From lie.1296 at gmail.com  Fri Jul  3 02:37:32 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:37:32 GMT
Subject: question of style
In-Reply-To: <mch3m.2328$ze1.1288@news-server.bigpond.net.au>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
	<VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>
	<mch3m.2328$ze1.1288@news-server.bigpond.net.au>
Message-ID: <MGh3m.2332$ze1.684@news-server.bigpond.net.au>

Lie Ryan wrote:
> Tim Harig wrote:
>>> Speaking only to the style issue, when I've wanted to do something like
>>> that, I find:
>>>        if self.higher is None is self.lower:
>>> more readable, by making clear they are both being compared to a
>>> constant, rather than compared to each other.
>> By comparing them to *any* constant with 'is' you end up with the same
>> potential problems as to whether something with a value of None is actually
>> None?  
> 
> Oh really? None is a Singleton and all None always point to the same
> None object. And the fact that it is impossible to override `is`
> operator is the reason for the "is None" idiom.
> 

http://docs.python.org/c-api/none.html


From aotto1968 at users.sourceforge.net  Fri Jul  3 02:39:17 2009
From: aotto1968 at users.sourceforge.net (Andreas Otto)
Date: Fri, 03 Jul 2009 08:39:17 +0200
Subject: ANNOUNCE: libmsgque 3.4
Message-ID: <h2k93v$m68$02$1@news.t-online.com>


Dear Users,

  I would like to provide a new !! Major Feature Release !! of 	

	>>> LibMsgque (3.4) <<<

  This Release Introduce a new technology called

	>>> Master / Slave - Link <<<

  and is used to create, mange and configure a MESH of
  node's (process or thread) distributed over multiple hosts.

  But a picture says more then all the words, read more at:

      -> http://libmsgque.sourceforge.net/master_versa_slave.htm

  To get the Details and the Downloads read more at:

      -> http://libmsgque.sourceforge.net/  

  P.S. sourceforge introduce a new interface yesterday ....
         and this has still some bugs ...
         to get the release 3.4 files you have to use the files link.


mfg

  Andreas Otto





From lie.1296 at gmail.com  Fri Jul  3 02:40:19 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:40:19 GMT
Subject: question of style
In-Reply-To: <7xljn6pvgk.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
Message-ID: <nJh3m.2333$ze1.1924@news-server.bigpond.net.au>

Paul Rubin wrote:
> Tim Harig <usernet at ilthio.net> writes:
>> That being the case, it might be a good idea either to handle the situation
>> and raise an exception or add:
>>
>> assert self.lower <= self.higher
>>
>> That way an exception will be raised if there is an error somewhere else
>> in the code rather then silently passing a possibly incorrect value.
> 
> Well, that assert is not right because you have to handle the case
> where one of the values is None.  The general sentiment is reasonable
> though, if you're concerned that the precondition may not be valid.

Well, it depends on where you put the assert statement. If your code is
like this:

if self.higher is self.lower is None: return
if self.lower is None: return self.higher
if self.higher is None: return self.lower
assert self.lower <= self.higher

then the assert statement is correct.

Some people might prefer to keep all asserts at the top of function though.


From ricli85 at gmail.com  Fri Jul  3 02:46:46 2009
From: ricli85 at gmail.com (Rickard Lindberg)
Date: Fri, 3 Jul 2009 08:46:46 +0200
Subject: Sequence splitting
In-Reply-To: <e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
	<e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
Message-ID: <890d8ab70907022346r635b00dfr5001e65838a1b994@mail.gmail.com>

> I tried posting on python-ideas and received a "You are not allowed to
> post to this mailing list" reply. Perhaps because I am posting through
> Google groups? Or maybe one must be an approved member to post?

If you got an "awaiting moderator approval" message you post might appear on
the list soon. The reason for getting those can be that it is a member only
list and you posted from another address. I am not sure if that was the message
you got.

-- 
Rickard Lindberg


From lie.1296 at gmail.com  Fri Jul  3 02:47:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:47:49 GMT
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <pQh3m.2334$ze1.180@news-server.bigpond.net.au>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?

If self is an object (and it must have been), it would be preferrable to
set self.higher and self.lower to a known value inside self.__init__ and
avoid having the comparison.

I'm guessing you have something like this in your __init__:

def __init__(self, lower=None, higher=None):
    self.lower = lower
    self.higher = higher


that should be changed to:

def __init__(self, lower=None, higher=None):
    self.lower = lower if lower is not None else higher
    self.higher = higher if lower is not None else lower

or whatever else-value you see is appropriate for the context.


From javier.collado at gmail.com  Fri Jul  3 02:55:28 2009
From: javier.collado at gmail.com (Javier Collado)
Date: Fri, 3 Jul 2009 08:55:28 +0200
Subject: Config files with different types
In-Reply-To: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
References: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
Message-ID: <c83cde5a0907022355y706ea932w78649a17ed756809@mail.gmail.com>

Hello,

Have you considered using something that is already developed?

You could take a look at this presentation for an overview of what's available:
http://us.pycon.org/2009/conference/schedule/event/5/

Anyway, let me explain that, since I "discovered" it, my favourite
format for configuration files is yaml (http://yaml.org/,
http://pyyaml.org/). It's easy to read, easy to write, available in
different programming languagues, etc. In addition to this, type
conversion is already in place so I think it covers your requirement.
For example:

IIn [1]: import yaml

In [2]: yaml.load("""name: person name
   ...: age: 25
   ...: is_programmer: true""")
Out[2]: {'age': 25, 'is_programmer': True, 'name': 'person name'}

Best regards,
    Javier

2009/7/2 Zach Hobesh <hobesh at gmail.com>:
> Hi all,
>
> I've written a function that reads a specifically formatted text file
> and spits out a dictionary. ?Here's an example:
>
> config.txt:
>
> Destination = C:/Destination
> Overwrite = True
>
>
> Here's my function that takes 1 argument (text file)
>
> the_file = open(textfile,'r')
> linelist = the_file.read().split('\n')
> the_file.close()
> configs = {}
> for line in linelist:
> ? ? ? try:
> ? ? ? ? ? ? ?key,value = line.split('=')
> ? ? ? ? ? ? ?key.strip()
> ? ? ? ? ? ? ?value.strip()
> ? ? ? ? ? ? ?key.lower()
> ? ? ? ? ? ? ?value.lower()
> ? ? ? ? ? ? ?configs[key] = value
>
> ? ? ? except ValueError:
> ? ? ? ? ? ? ?break
>
> so I call this on my config file, and then I can refer back to any
> config in my script like this:
>
> shutil.move(your_file,configs['destination'])
>
> which I like because it's very clear and readable.
>
> So this works great for simple text config files. ?Here's how I want
> to improve it:
>
> I want to be able to look at the value and determine what type it
> SHOULD be. ?Right now, configs['overwrite'] = 'true' (a string) when
> it might be more useful as a boolean. ?Is there a quick way to do
> this? ?I'd also like to able to read '1' as an in, '1.0' as a float,
> etc...
>
> I remember once I saw a script that took a string and tried int(),
> float() wrapped in a try except, but I was wondering if there was a
> more direct way.
>
> Thanks in advance,
>
> Zach
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From hv at tbz-pariv.de  Fri Jul  3 03:02:06 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Fri, 03 Jul 2009 09:02:06 +0200
Subject: logging of strings with broken encoding
In-Reply-To: <4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
	<4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>
Message-ID: <7b5oneF223712U1@mid.individual.net>

Stefan Behnel schrieb:
> Thomas Guettler wrote:
>> My quick fix is this:
>>
>> class MyFormatter(logging.Formatter):
>>     def format(self, record):
>>         msg=logging.Formatter.format(self, record)
>>         if isinstance(msg, str):
>>             msg=msg.decode('utf8', 'replace')
>>         return msg
>>
>> But I still think handling of non-ascii byte strings should be better.
>> A broken logging message is better than none.
> 
> Erm, may I note that this is not a problem in the logging library but in
> the code that uses it?

I know that my code passes the broken string to the logging module. But maybe
I get the non-ascii byte string from a third party (psycopg2 sometime passes
latin1 byte strings from postgres in error messages).

I like Python very much because "it refused to guess". But in this case, "best effort"
is a better approach.

It worked in 2.5 and will in py3k. I think it is a bug, that it does not in 2.6.

 Thomas



-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From lie.1296 at gmail.com  Fri Jul  3 03:16:35 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 07:16:35 GMT
Subject: Sequence splitting
In-Reply-To: <890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
Message-ID: <nfi3m.2341$ze1.1151@news-server.bigpond.net.au>

Brad wrote:
> On Jul 2, 9:40 pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>> If it is speed that we are after, it's my understanding that map and
>> filter are faster than iterating with the for statement (and also
>> faster than list comprehensions).  So here is a rewrite:
>>
>> def split(seq, func=bool):
>>         t = filter(func, seq)
>>         f = filter(lambda x: not func(x), seq)
>>         return list(t), list(f)
>>
> 
> In my simple tests, that takes 1.8x as long as the original solution.
> Better than the itertools solution, when "func" is short and fast. I
> think the solution here would worse if func was more complex.
> 
> Either way, what I am still wondering is if people would find a built-
> in implementation useful?
> 
> -Brad

A built-in/itertools should always try to provide the general solution
to be as useful as possible, something like this:

def group(seq, func=bool):
    ret = {}
    for item in seq:
        fitem = func(item)
        try:
            ret[fitem].append(item)
        except KeyError:
            ret[fitem] = [item]
    return ret

definitely won't be faster, but it is a much more general solution.
Basically, the function allows you to group sequences based on the
result of func(item). It is similar to itertools.groupby() except that
this also group non-contiguous items.


From lie.1296 at gmail.com  Fri Jul  3 03:25:28 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 07:25:28 GMT
Subject: logging of strings with broken encoding
In-Reply-To: <7b5oneF223712U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
	<4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>
	<7b5oneF223712U1@mid.individual.net>
Message-ID: <Ini3m.2342$ze1.1804@news-server.bigpond.net.au>

Thomas Guettler wrote:
> Stefan Behnel schrieb:
>> Thomas Guettler wrote:
>>> My quick fix is this:
>>>
>>> class MyFormatter(logging.Formatter):
>>>     def format(self, record):
>>>         msg=logging.Formatter.format(self, record)
>>>         if isinstance(msg, str):
>>>             msg=msg.decode('utf8', 'replace')
>>>         return msg
>>>
>>> But I still think handling of non-ascii byte strings should be better.
>>> A broken logging message is better than none.
>> Erm, may I note that this is not a problem in the logging library but in
>> the code that uses it?
> 
> I know that my code passes the broken string to the logging module. But maybe
> I get the non-ascii byte string from a third party (psycopg2 sometime passes
> latin1 byte strings from postgres in error messages).

If the database contains non-ascii byte string, then you could repr()
them before logging (repr also adds some niceties such as quotes). I
think that's the best solution, unless you want to decode the byte
string (which might be an overkill, depending on the situation).

> I like Python very much because "it refused to guess". But in this case, "best effort"
> is a better approach.

One time it refused to guess, then the next time it tries best effort. I
don't think Guido liked such inconsistency.

> It worked in 2.5 and will in py3k. I think it is a bug, that it does not in 2.6.

In python 3.x, the default string is unicode string. If it works in
python 2.5, then it is a bug in 2.5


From http  Fri Jul  3 03:27:54 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 00:27:54 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x63eahp8z.fsf@ruckus.brouhaha.com>
	<zCh3m.2331$ze1.2286@news-server.bigpond.net.au>
Message-ID: <7x8wj6usxx.fsf@ruckus.brouhaha.com>

Lie Ryan <lie.1296 at gmail.com> writes:
> I guess in python, None as the missing datum idiom is still quite prevalent:

Well, sometimes there is no way around it, but:

> def cat_list(a=None, b=None):
>     # poor man's list concatenation
>     if a is None and b is None: return []
>     if a is None: return b
>     if b is None: return a
>     return a + b

def cat_list(a=[], b=[]):
    return a + b


From nillgump at gmail.com  Fri Jul  3 03:31:27 2009
From: nillgump at gmail.com (nillgump)
Date: Fri, 3 Jul 2009 00:31:27 -0700 (PDT)
Subject: use python to edit pdf document
Message-ID: <7094d63e-21a6-4b1a-995a-280b0b1b26c4@q40g2000prh.googlegroups.com>

hi all.
I  are looking for some packages which use python to edit pdf format
docutment.
when I searched the internet,I found  the
paper  " Using Python as PDF Editing and Processing Framework"  which
is at:
*********http://www.python.org/workshops/2002-02/papers/17/
index.htm*********
this paper is posted at  2002.it  had a  long  years.But I cann't
find  the impletation.
Does anyone know what  happened  about
this?And  I  have seen the Reportlab  which can generate the pdf .But
what I  want is not only this,but also can edit the pdf.
So does  everyone know there  are some
exsiting python packages about this?
With using the exsiting  things,I can save
much work.
Any advice is  appropriated!

--nillgump
--2009/7/3
--China


From lie.1296 at gmail.com  Fri Jul  3 03:31:45 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 07:31:45 GMT
Subject: Sequence splitting
In-Reply-To: <mailman.2541.1246603608.8015.python-list@python.org>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>	<e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
	<mailman.2541.1246603608.8015.python-list@python.org>
Message-ID: <Bti3m.2343$ze1.992@news-server.bigpond.net.au>

Rickard Lindberg wrote:
>> I tried posting on python-ideas and received a "You are not allowed to
>> post to this mailing list" reply. Perhaps because I am posting through
>> Google groups? Or maybe one must be an approved member to post?
> 
> If you got an "awaiting moderator approval" message you post might appear on
> the list soon. The reason for getting those can be that it is a member only
> list and you posted from another address. I am not sure if that was the message
> you got.
> 

AFAIK, python-ideas is not moderated (I followed python-ideas). I've
never used Google Groups to access it though. Try subscribing to the
mailing list directly (instead of using Google Group's web-gateway)
here: http://mail.python.org/mailman/listinfo/python-ideas


From clp2 at rebertia.com  Fri Jul  3 03:44:43 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 00:44:43 -0700
Subject: use python to edit pdf document
In-Reply-To: <7094d63e-21a6-4b1a-995a-280b0b1b26c4@q40g2000prh.googlegroups.com>
References: <7094d63e-21a6-4b1a-995a-280b0b1b26c4@q40g2000prh.googlegroups.com>
Message-ID: <50697b2c0907030044p740e0e96h3f1ac9a81b578d57@mail.gmail.com>

On Fri, Jul 3, 2009 at 12:31 AM, nillgump<nillgump at gmail.com> wrote:
> hi all.
> I ?are looking for some packages which use python to edit pdf format
> docutment.
> when I searched the internet,I found ?the
> paper ?" Using Python as PDF Editing and Processing Framework" ?which
> is at:
> *********http://www.python.org/workshops/2002-02/papers/17/
> index.htm*********
> this paper is posted at ?2002.it ?had a ?long ?years.But I cann't
> find ?the impletation.
> Does anyone know what ?happened ?about
> this?And ?I ?have seen the Reportlab ?which can generate the pdf .But
> what I ?want is not only this,but also can edit the pdf.

See ReportLab's proprietary+commercial PageCatcher library
(http://developer.reportlab.com/).

Cheers,
Chris
-- 
http://blog.rebertia.com


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 03:50:53 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 07:50:53 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
Message-ID: <025da9f8$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 21:56:40 -0700, Paul Rubin wrote:

>> Well I wouldn't know, I've been fortunate enough to program mostly in
>> python for over half a decade now and None and 0 are as close as I've
>> gotten to NULL in a long time.
> 
> Right, and how many times have you had to debug
> 
>    AttributeError: 'NoneType' object has no attribute 'foo'

Hardly ever, and mostly when I do something silly like:

another_list = alist.sort()

Of course, YMMV.



> or the equivalent null pointer exceptions in Java, C, or whatever? They
> are very common.  And the basic idea is that if you avoid using null
> pointers in the first place, you'll get fewer accidental null pointer
> exceptions.

And some other error instead, due to the bugs in your more complicated 
code *wink*



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 03:57:02 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 07:57:02 GMT
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
Message-ID: <025dab69$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 22:10:14 -0500, Pablo Torres N. wrote:

> This sounds like it belongs to the python-ideas list.  I suggest posting
> there for better feedback, since the core developers check that list
> more often than this one.

If you post to python-ideas, you'll probably be told to gather feedback 
here first. The core-developers aren't hugely interested in arbitrary new 
features unless they have significant community support.

I've never needed such a split function, and I don't like the name, and 
the functionality isn't general enough. I'd prefer something which splits 
the input sequence into as many sublists as necessary, according to the 
output of the key function. Something like itertools.groupby(), except it 
runs through the entire sequence and collates all the elements with 
identical keys.

E.g.:

splitby(range(10), lambda n: n%3)
=> [ (0, [0, 3, 6, 9]),
     (1, [1, 4, 7]), 
     (2, [2, 5, 8]) ]

Your split() would be nearly equivalent to this with a key function that 
returns a Boolean.



-- 
Steven




From http  Fri Jul  3 04:02:56 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 01:02:56 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7x1voy5h3j.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> I've never needed such a split function, and I don't like the name, and 
> the functionality isn't general enough. I'd prefer something which splits 
> the input sequence into as many sublists as necessary, according to the 
> output of the key function. Something like itertools.groupby(), except it 
> runs through the entire sequence and collates all the elements with 
> identical keys.

No really, groupby makes iterators, not lists, and it you have to
develop quite a delicate sense of when you can use it without having
bugs caused by the different iterators it makes getting advanced at
the wrong times.  The concept of a split function that actually works
on lists is useful.  I'm neutral about whether it's worth having a C
version in the stdlib.


From lie.1296 at gmail.com  Fri Jul  3 04:06:18 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 08:06:18 GMT
Subject: question of style
In-Reply-To: <7x8wj6usxx.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x63eahp8z.fsf@ruckus.brouhaha.com>
	<zCh3m.2331$ze1.2286@news-server.bigpond.net.au>
	<7x8wj6usxx.fsf@ruckus.brouhaha.com>
Message-ID: <_Zi3m.2347$ze1.458@news-server.bigpond.net.au>

Paul Rubin wrote:
> Lie Ryan <lie.1296 at gmail.com> writes:
>> I guess in python, None as the missing datum idiom is still quite prevalent:
> 
> Well, sometimes there is no way around it, but:
> 
>> def cat_list(a=None, b=None):
>>     # poor man's list concatenation
>>     if a is None and b is None: return []
>>     if a is None: return b
>>     if b is None: return a
>>     return a + b
> 
> def cat_list(a=[], b=[]):
>     return a + b

Being super contrived is why I tagged it as poor man's concat.
Generally, there will be a processing:

...
    if b is None: return a
    # processing here
    return retlist
...

and it will not be about concatenating two lists, but something more
complex. But I thought that was unnecessary since I just want to mention
about the None argument idiom.


From stef.mientki at gmail.com  Fri Jul  3 04:07:50 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Fri, 03 Jul 2009 10:07:50 +0200
Subject: Adding an object to the global namespace through " f_globals"
	is that allowed ?
In-Reply-To: <4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>
References: <4A4BC22D.70502@gmail.com>	<mailman.2467.1246512323.8015.python-list@python.org>
	<4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>
Message-ID: <4A4DBC56.9020202@gmail.com>

ryles wrote:
> On Jul 2, 1:25 am, Terry Reedy <tjre... at udel.edu> wrote:
>   
>>> The next statement works,
>>> but I'm not sure if it will have any dramatical side effects,
>>> other than overruling a possible object with the name A
>>>       
>>> def some_function ( ...) :
>>>      A = object ( ...)
>>>      sys._getframe(1).f_globals [ Name ] = A
>>>       
>> global name
>> name = A
>>
>> or is name is a string var
>> globals()[name] = A
>>     
>
> It wasn't explicit, but I think Stef meant that the global should be
> added to the caller's environment, which was the reason for
> sys._getframe().
>
> Is this environment only intended for interactive use? I wonder if you
> might just set things up
> in a PYTHONSTARTUP script instead.
>   
the idea is to get a simple environment where you can do interactive 3D 
geometry,
without knowing anything about Python.
So to create a triangle e.g., the whole program will look like this:

Point ( 'A', (1,1,0) )
Point ( 'B', (5,5,0) )
Point ( 'C', (1,5,0) )
Line_Segment ( 'AB' )
Line_Segment ( 'BC' ) 
Line_Segment ( 'AC' )

   

And now the points A,B,C and the line segments AB,BC,AC also exists as 
variables in the namespace of the above environment.
So now you can add a point "D" in the middle of the line-segment AB, by 
giving the formula of that point:

Point ( 'D',  ' ( A + B ) / 2 ' )

Or display the properties of point A, with :

Print A

which (for the moment) will result in:

Point Instance: A
  Childs : AB(Line-Segment), AC(Line-Segment),
  Parents:

The graphics above is done in VPython, which gives you an easy way to 
make all objects dragable,
and if objects are defined by formulas, the will stick together 
according to that formula.

And now it's obvious I can't use the solution of Terry,
because I don't know what names will to become global.

thanks,
Stef


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/f1a53503/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: moz-screenshot-3.jpg
Type: image/jpeg
Size: 3333 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/f1a53503/attachment.jpg>

From ldo at geek-central.gen.new_zealand  Fri Jul  3 04:08:20 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Fri, 03 Jul 2009 20:08:20 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
	<mailman.2446.1246491262.8015.python-list@python.org>
Message-ID: <h2ke9k$os8$3@lust.ihug.co.nz>

In message <mailman.2446.1246491262.8015.python-list at python.org>, Jo?o 
Valverde wrote:

> Lawrence D'Oliveiro wrote:
>
>> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o
>> Valverde wrote:
>>   
>>> Simple example usage case: Insert string into data structure in sorted
>>> order if it doesn't exist, else retrieve it.
>>
>>     the_set = set( ... )
>>
>>     if str in the_set :
>>         ... "retrieval" case ...
>>     else :
>>         the_set.add(str)
>>     #end if
>>
>> Want sorted order?
>>
>>     sorted(tuple(the_set))
>>
>> What could be simpler?
> 
> Try putting that inside a loop with thousands of iterations and you'll
> see what the problem is.

You could apply the same argument to anything. E.g. why create a tree 
structure with a million elements? Try putting that inside a loop with 
thousands of iterations and you'll see what the problem is.



From deets at nospam.web.de  Fri Jul  3 04:11:02 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 03 Jul 2009 10:11:02 +0200
Subject: XML(JSON?)-over-HTTP:  How to define API?
In-Reply-To: <mailman.2520.1246573083.8015.python-list@python.org>
References: <mailman.2520.1246573083.8015.python-list@python.org>
Message-ID: <7b5somF21peceU1@mid.uni-berlin.de>

Allen Fowler schrieb:
> 
> 
> 
>> I have an (in-development) python system that needs to shuttle events / requests 
>> around over the network to other parts of itself.   It will also need to 
>> cooperate with a .net application running on yet a different machine.
>>
>> So, naturally I figured some sort of HTTP event / RPC type of would be a good 
>> idea?
>>
>> Are there any modules I should know about, or guidelines I could read, that 
>> could aid me in the design of the API?    
>>
>>
> 
> 
> To clarify:
> 
> Each message would be <1KB of data total, and consist of some structured object containing strings, numbers, dates, etc.
> 
> For instance there would be an "add user" request that would contain one or more User objects each having a number of properties like:
> 
> - Full Name
> - Username
> - Password
> - Email addresses (a variable length array)
> - Street Address line1
> - Street Address line1
> - Street Address line1
> - City
> - State
> - Zip
> - Sign Up Date
> 
> .... and so on.
> 
> 
> Since I need to work with other platforms, pickle is out...  what are the alternatives?  XML? JSON?
> 
> How should I formally define each of the valid messages and objects?
> 
> Thank you,

Use XMLRPC. Implementations for both languages are available. There is 
no need for formal spec - which is a good thing. You just call the 
server, and it works.

Diez


From clp2 at rebertia.com  Fri Jul  3 04:12:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 01:12:20 -0700
Subject: Sequence splitting
In-Reply-To: <890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
Message-ID: <50697b2c0907030112g38a3c992tb07eea45acc58312@mail.gmail.com>

On Thu, Jul 2, 2009 at 11:31 PM, Brad<schickb at gmail.com> wrote:
> On Jul 2, 9:40?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>>
>> If it is speed that we are after, it's my understanding that map and
>> filter are faster than iterating with the for statement (and also
>> faster than list comprehensions). ?So here is a rewrite:
>>
>> def split(seq, func=bool):
>> ? ? ? ? t = filter(func, seq)
>> ? ? ? ? f = filter(lambda x: not func(x), seq)
>> ? ? ? ? return list(t), list(f)
>>
>
> In my simple tests, that takes 1.8x as long as the original solution.
> Better than the itertools solution, when "func" is short and fast. I
> think the solution here would worse if func was more complex.
>
> Either way, what I am still wondering is if people would find a built-
> in implementation useful?

FWIW, Ruby has Enumerable#partition, which does the same thing as
split() and has a better name IMHO.
http://www.ruby-doc.org/core/classes/Enumerable.html#M003130

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Fri Jul  3 04:15:35 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 01:15:35 -0700
Subject: Adding an object to the global namespace through " f_globals" is 
	that allowed ?
In-Reply-To: <4A4DBC56.9020202@gmail.com>
References: <4A4BC22D.70502@gmail.com>
	<mailman.2467.1246512323.8015.python-list@python.org>
	<4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>
	<4A4DBC56.9020202@gmail.com>
Message-ID: <50697b2c0907030115l5aab4816i159eb22d39785f0f@mail.gmail.com>

On Fri, Jul 3, 2009 at 1:07 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
> ryles wrote:
>
> On Jul 2, 1:25 am, Terry Reedy <tjre... at udel.edu> wrote:
>
>
> The next statement works,
> but I'm not sure if it will have any dramatical side effects,
> other than overruling a possible object with the name A
>
>
> def some_function ( ...) :
>      A = object ( ...)
>      sys._getframe(1).f_globals [ Name ] = A
>
>
> global name
> name = A
>
> or is name is a string var
> globals()[name] = A
>
>
> It wasn't explicit, but I think Stef meant that the global should be
> added to the caller's environment, which was the reason for
> sys._getframe().
>
> Is this environment only intended for interactive use? I wonder if you
> might just set things up
> in a PYTHONSTARTUP script instead.
>
>
> the idea is to get a simple environment where you can do interactive 3D
> geometry,
> without knowing anything about Python.
> So to create a triangle e.g., the whole program will look like this:
>
> Point ( 'A', (1,1,0) )
> Point ( 'B', (5,5,0) )
> Point ( 'C', (1,5,0) )
> Line_Segment ( 'AB' )
> Line_Segment ( 'BC' )
> Line_Segment ( 'AC' )
>
>
>
> And now the points A,B,C and the line segments AB,BC,AC also exists as
> variables in the namespace of the above environment.
> So now you can add a point "D" in the middle of the line-segment AB, by
> giving the formula of that point:
>
> Point ( 'D',? ' ( A + B ) / 2 ' )
>
> Or display the properties of point A, with :
>
> Print A
>
> which (for the moment) will result in:
>
> Point Instance: A
> ? Childs : AB(Line-Segment), AC(Line-Segment),
> ? Parents:
>
> The graphics above is done in VPython, which gives you an easy way to make
> all objects dragable,
> and if objects are defined by formulas, the will stick together according to
> that formula.
>
> And now it's obvious I can't use the solution of Terry,
> because I don't know what names will to become global.

Have you considered just using imports instead? Requiring a single opaque:

from graphicslibthingy import *

at the start of a file using the environment isn't so bad, IMHO.

Cheers,
Chris
-- 
http://blog.rebertia.com


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:18:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:18:19 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
Message-ID: <025db066$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 22:14:18 +0000, Tim Harig wrote:

> On 2009-07-02, Paul Rubin <http> wrote:
>> Tim Harig <usernet at ilthio.net> writes:
>>> If lower is 5 and higher is 3, then it returns 3 because 3 != None in
>>> the first if.
>> Sorry, the presumption was that lower <= higher, i.e. the comparison
>> had already been made and the invariant was enforced by the class
>> constructor.  The comment should have been more explicit, I guess.
> 
> That being the case, it might be a good idea either to handle the
> situation and raise an exception or add:
> 
> assert self.lower <= self.higher

Only if you want strange and mysterious bugs whenever somebody runs your 
code with the -O flag.

 
> That way an exception will be raised if there is an error somewhere else
> in the code rather then silently passing a possibly incorrect value.

asserts are disabled when the -O flag is given.

You should never use asserts for testing data. That's not what they're 
for. They're for testing program logic (and unit-testing).

This is wrong, because it will sometimes fail when running under -O:

def parrot(colour):
    assert colour.lower() in ('red', 'green', 'blue')
    return "Norwegian %s" % colour.title()

That should be written as test followed by an explicit raise:

def parrot(colour):
    if colour.lower() not in ('red', 'green', 'blue'):
        raise ValueError
    return "Norwegian %s" % colour.title()


An acceptable use for assert is to verify your program logic by testing 
something which should never fail. If it does fail, then you know 
something bizarre and unexpected has happened, and you have a program bug 
rather than bad data. Here's a silly example:


def cheese_available(kind):
    """Return True if the kind of cheese specified is in stock
    in the cheeseshop run by Michael Palin.

    This function always returns False.
    """
    return False


def get_cheese():
    exchange_amusing_banter()
    for kind in ('Cheddar', 'Gouda', 'Swiss', 'Camembert'):
        ask_proprietor("Do you have any %s?" % kind)
        flag = cheese_available(kind)
        assert not flag
        if flag:
            buy_cheese(kind)
            return None
        else:
            express_disappointment()
    # We only get here if no cheese is bought.
    print "Cleese: Does this cheeseshop actually have ANY cheese?"
    print "Palin: No sir, I'm afraid I've been wasting your time."
    print "Cleese: Well then, I'm going to have to shoot you."



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:19:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:19:23 GMT
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
Message-ID: <025db0a6$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:

> I'm sure that it is possible to find cases in which the *current*
> implementation of re.search() would be inefficient, but that's because
> this implementation is perverse, which, I guess, is ultimately the point
> of my original post.  Why privilege the special case of a
> start-of-string anchor?  

Because wanting to see if a string matches from the beginning is a very 
important and common special case.


> What if you wanted to apply an end-anchored
> pattern to some prefix of your 4GB string?  Why not have a special re
> method for that?  And another for every possible special case?

Because they're not common special cases. They're rare and not special 
enough to justify special code.


> If the concern is efficiency for such cases, then simply implement
> optional offset and length parameters for re.search(), to specify any
> arbitrary substring to apply the search to.  To have a special-case
> re.match() method in addition to a general re.search() method is
> antithetical to language minimalism, and plain-old bizarre.  Maybe
> there's a really good reason for it, but it has not been mentioned yet.

There is, and it has. You're welcome to keep your own opinion, but I 
don't think you'll find many experienced Python coders will agree with it.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:21:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:21:09 GMT
Subject: PEP368 and pixeliterators
References: <mailman.2475.1246523526.8015.python-list@python.org>
Message-ID: <025db110$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 10:32:04 +0200, Joachim Str?mbergson wrote:

> for pixel in rgb_image:
>     # swap red and blue, and set green to 0 pixel.value = pixel.b, 0,
>     pixel.r
> 
> 
> The idea I'm having is that fundamentally the image is made up of a 2D
> array of pixels, not rows of pixels.

A 2D array implies rows (and columns) of pixels.




-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:26:59 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:26:59 GMT
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
Message-ID: <025db26e$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 01:02:56 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> I've never needed such a split function, and I don't like the name, and
>> the functionality isn't general enough. I'd prefer something which
>> splits the input sequence into as many sublists as necessary, according
>> to the output of the key function. Something like itertools.groupby(),
>> except it runs through the entire sequence and collates all the
>> elements with identical keys.
> 
> No really, groupby makes iterators, not lists, and it you have to
> develop quite a delicate sense of when you can use it without having
> bugs caused by the different iterators it makes getting advanced at the
> wrong times.  The concept of a split function that actually works on
> lists is useful.  I'm neutral about whether it's worth having a C
> version in the stdlib.

groupby() works on lists.

The difference between what I'm suggesting and what groupby() does is 
that my suggestion would collate *all* the elements with the same key, 
not just runs of them. This (as far as I can tell) requires returning 
lists rather than iterators.

The most important difference between my suggestion and that of the OP is 
that he limited the key function to something which returns a truth 
value, while I'm looking for something more general which can split the 
input into an arbitrary number of collated sublists.



-- 
Steven


From nick at craig-wood.com  Fri Jul  3 04:30:02 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Fri, 03 Jul 2009 03:30:02 -0500
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
	<25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>
	<Zua3m.3615$Jb1.1092@flpi144.ffdc.sbc.com>
	<mailman.2529.1246584451.8015.python-list@python.org>
Message-ID: <slrnh4refh.vpl.nick@irishsea.home.craig-wood.com>

Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>  En Thu, 02 Jul 2009 19:27:05 -0300, Tim Harig <usernet at ilthio.net>
>  escribi?:
> > On 2009-07-02, sanket <sanket.s.patel at gmail.com> wrote:
> >>> sanket wrote:
> >>> > I am trying to use python's subprocess module to launch a process.
> >>> > but in order to do that I have to change the user.
> >> I am using python 2.4 on centos.
> >
> > I have never done this in python; but, using the normal system calls in C
> > the process is basically:
> > 	
> > 	1. fork() a  new process
> > 	2. the child process changes its user id with setreuid() and
> > 		possibly its group id with setregid()
> > 	3. then the child exec()s new process which replaces itself
> >
> > All of the necessary functions should be under the os module on POSIX
> > operating systems.
> 
>  How to do that using the subprocess module: write a function for item (2)
>  above and pass it as the preexec_fn argument to Popen. preexec_fn is
>  executed after fork() and before exec()

If you are forking 100s of processes a second you want to use the
method above, however I think it is easier to use su (assuming you
start off as root),

so instead of passing

  ['mycommand', 'my_arg1', 'my_arg2']

to Popen, pass

  ['su', '-', 'username', '-c', 'mycommand my_arg1 my_arg2']

There is some opportunity for quoting problems there, but it is easy!

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From http  Fri Jul  3 04:33:27 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 01:33:27 -0700
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
	<mailman.2446.1246491262.8015.python-list@python.org>
	<h2ke9k$os8$3@lust.ihug.co.nz>
Message-ID: <7xocs2go88.fsf@ruckus.brouhaha.com>

Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> writes:
> >> Want sorted order?
> >>     sorted(tuple(the_set))
> >> What could be simpler?
> > 
> > Try putting that inside a loop with thousands of iterations and you'll
> > see what the problem is.
> 
> You could apply the same argument to anything. E.g. why create a tree 
> structure with a million elements? Try putting that inside a loop with 
> thousands of iterations and you'll see what the problem is.

The idea is you're going to insert or delete something in the tree
structure at each iteration, an O(log n) operation, making the whole
loop O(n log n).  If you sort a set (which is O(n log n)) inside the
loop then you end up with O(n**2 log n) which is impractical.  A
reason you might sort inside the loop might be to find the nearby
neighbors of the new element or traverse some elements in the middle.
This is trivial with a tree structure but messy with something like
sets.


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:39:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:39:19 GMT
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
	<mailman.2446.1246491262.8015.python-list@python.org>
	<h2ke9k$os8$3@lust.ihug.co.nz>
Message-ID: <025db552$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 20:08:20 +1200, Lawrence D'Oliveiro wrote:

> In message <mailman.2446.1246491262.8015.python-list at python.org>, Jo?o
> Valverde wrote:
> 
>> Lawrence D'Oliveiro wrote:
[...]
>>> Want sorted order?
>>>
>>>     sorted(tuple(the_set))
>>>
>>> What could be simpler?
>> 
>> Try putting that inside a loop with thousands of iterations and you'll
>> see what the problem is.
> 
> You could apply the same argument to anything. E.g. why create a tree
> structure with a million elements? Try putting that inside a loop with
> thousands of iterations and you'll see what the problem is.

The difference is, it's vanishingly rare to want to build a tree with 
millions of elements thousands of times over and over again, but it is 
not unreasonable to want to access sorted data thousands of times. 
Needing to re-sort it over and over and over again is wasteful, slow and 
stupid. Binary trees were invented, in part, specifically to solve this 
use-case.



-- 
Steven


From http  Fri Jul  3 04:39:27 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 01:39:27 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
	<025db26e$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xk52qgny8.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> groupby() works on lists.

>>> a = [1,3,4,6,7]
>>> from itertools import groupby
>>> b = groupby(a, lambda x: x%2==1)  # split into even and odd
>>> c = list(b)
>>> print len(c)
3
>>> d = list(c[1][1])    # should be [4,6]
>>> print d  # oops.
[]

> The difference between what I'm suggesting and what groupby() does is 
> that my suggestion would collate *all* the elements with the same key, 
> not just runs of them. This (as far as I can tell) requires returning 
> lists rather than iterators.

I guess that is reasonable.

> The most important difference between my suggestion and that of the OP is 
> that he limited the key function to something which returns a truth 
> value, while I'm looking for something more general which can split the 
> input into an arbitrary number of collated sublists.

Also ok.


From pyklass at gmail.com  Fri Jul  3 04:55:04 2009
From: pyklass at gmail.com (Goksie Aruna)
Date: Fri, 03 Jul 2009 09:55:04 +0100
Subject: is it possible to write USSD / SMS /SS7 apps in python
Message-ID: <4A4DC768.40604@gmail.com>

Can someone give me an insight into these?

    developing ss7 or USSD or SMS apps in python.

is there any existing ones in this manner?

Thanks





From tsangpo.newsgroup at gmail.com  Fri Jul  3 05:03:51 2009
From: tsangpo.newsgroup at gmail.com (tsangpo)
Date: Fri, 3 Jul 2009 17:03:51 +0800
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
	<nfi3m.2341$ze1.1151@news-server.bigpond.net.au>
Message-ID: <h2khkq$159j$1@adenine.netfront.net>

Just a shorter implementation:

from itertools import groupby
def split(lst, func):
    gs = groupby(lst, func)
    return list(gs[True]), list(gs[False])


"Lie Ryan" <lie.1296 at gmail.com> ????????????:nfi3m.2341$ze1.1151 at news-server.bigpond.net.au...
> Brad wrote:
>> On Jul 2, 9:40 pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>>> If it is speed that we are after, it's my understanding that map and
>>> filter are faster than iterating with the for statement (and also
>>> faster than list comprehensions).  So here is a rewrite:
>>>
>>> def split(seq, func=bool):
>>>         t = filter(func, seq)
>>>         f = filter(lambda x: not func(x), seq)
>>>         return list(t), list(f)
>>>
>>
>> In my simple tests, that takes 1.8x as long as the original solution.
>> Better than the itertools solution, when "func" is short and fast. I
>> think the solution here would worse if func was more complex.
>>
>> Either way, what I am still wondering is if people would find a built-
>> in implementation useful?
>>
>> -Brad
>
> A built-in/itertools should always try to provide the general solution
> to be as useful as possible, something like this:
>
> def group(seq, func=bool):
>    ret = {}
>    for item in seq:
>        fitem = func(item)
>        try:
>            ret[fitem].append(item)
>        except KeyError:
>            ret[fitem] = [item]
>    return ret
>
> definitely won't be faster, but it is a much more general solution.
> Basically, the function allows you to group sequences based on the
> result of func(item). It is similar to itertools.groupby() except that
> this also group non-contiguous items. 




From usernet at ilthio.net  Fri Jul  3 05:07:30 2009
From: usernet at ilthio.net (Tim Harig)
Date: Fri, 03 Jul 2009 09:07:30 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<025db066$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <mTj3m.2213$Wj7.1361@nlpi065.nbdc.sbc.com>

On 2009-07-03, Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
> On Thu, 02 Jul 2009 22:14:18 +0000, Tim Harig wrote:
>> On 2009-07-02, Paul Rubin <http> wrote:
>>> Tim Harig <usernet at ilthio.net> writes:
>>>> If lower is 5 and higher is 3, then it returns 3 because 3 != None in
>>>> the first if.
>>> Sorry, the presumption was that lower <= higher, i.e. the comparison
>>> had already been made and the invariant was enforced by the class
>>> constructor.  The comment should have been more explicit, I guess.
>> That being the case, it might be a good idea either to handle the
>> situation and raise an exception or add:
>> assert self.lower <= self.higher
> Only if you want strange and mysterious bugs whenever somebody runs your 
> code with the -O flag.

The point here is that Rubin presumed that the condition where lower >
higher should never exist.  Therefore, because the program given segment of
program doesn't test it elswhere, it is possible that a bug in the code
that sets lower > higher could go unoticed while silently passing the wrong
data.

Therefore, It is better to test that assumption in a way that *will* crash
if something is wrong, for instance, if another method accidently changes
one of the values.  That would tend to make errors in another method of the
class (or even higher up in this method), more likely to be found.

> asserts are disabled when the -O flag is given.

Right, like defining NDEBUG in C.  In _Writing Solid Code_ by Steve
Maguire, he likens it to having two pieces of code: one for testing where
any errors should cause crashes as early as possible and one for shipping
where it may be better to handle errors if possible from within the code.

> You should never use asserts for testing data. That's not what they're 
> for. They're for testing program logic (and unit-testing).

What I am suggesting here is exactly that.  If lower is always defined such
that it should always be equal to or lower then higher, then there is an
error in the code somewhere if lower is higher by the time this code is
called.  Either the constructor didn't didn't reject input properly or
another method within the class has inadvertantly changed higher or lower
in an uncorrect way.

In any event, whether I am using it 100% correctly, I want to find any
errors in my code.  If there is an error, I want the program to crash
during testing rather then silently passing bad data.  assert will help
here.

Unfortunatly, Rubin is right.  I did make the mistake that the assert will
fail with higher or lower values of None, which is allowed here.  The same
basic premise is correct but will require more complex assertions to allow
that through.


From mjohnson at cfi.co.ug  Fri Jul  3 05:18:04 2009
From: mjohnson at cfi.co.ug (Johnson Mpeirwe)
Date: Fri, 03 Jul 2009 12:18:04 +0300
Subject: PSP Caching
Message-ID: <4A4DCCCC.6040605@cfi.co.ug>

Hello All,

How do I stop caching of Python Server Pages (or whatever causes changes 
in a page not to be noticed in a web browser)? I am new to developing 
web applications in Python and after looking at implementations of PSP 
like Spyce (which I believed introduces new unnecessary non-PSP syntax), 
I decided to write my own PSP applications from scratch. When I modify a 
file, I keep getting the old results until I intentionally introduce an 
error (e.g parse error) and correct it after to have the changes 
noticed. There's no proxy (I am working on a windows machine unplugged 
from the network). I have Googled and no documents seem to talk about 
this. Is there any particular mod_python directive I must set in my 
Apache configuration to fix this?

Any help will be highly appreciated.

Johnson


From clp2 at rebertia.com  Fri Jul  3 05:21:33 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 02:21:33 -0700
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <4A4DC768.40604@gmail.com>
References: <4A4DC768.40604@gmail.com>
Message-ID: <50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>

On Fri, Jul 3, 2009 at 1:55 AM, Goksie Aruna<pyklass at gmail.com> wrote:
> Can someone give me an insight into these?
>
> ? developing ss7 or USSD or SMS apps in python.
>
> is there any existing ones in this manner?

Advice for the future: STFW.

http://pypi.python.org/pypi?%3Aaction=search&term=sms&submit=search

Cheers,
Chris
-- 
http://blog.rebertia.com


From pyklass at gmail.com  Fri Jul  3 05:31:38 2009
From: pyklass at gmail.com (Goke Aruna)
Date: Fri, 3 Jul 2009 10:31:38 +0100
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
Message-ID: <30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>

On Fri, Jul 3, 2009 at 10:21 AM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Fri, Jul 3, 2009 at 1:55 AM, Goksie Aruna<pyklass at gmail.com> wrote:
> > Can someone give me an insight into these?
> >
> >   developing ss7 or USSD or SMS apps in python.
> >
> > is there any existing ones in this manner?
>
> Advice for the future: STFW.
>
> http://pypi.python.org/pypi?%3Aaction=search&term=sms&submit=search
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>


thanks Chris,

however, i have checked all the packages there are specifics for a
particular company or device.

what am saying is reading the ITU info on USSD, is it possible to use python
to write the application SS7 with support for TCAP/MAP talking to E1 card to
do the ss7 signalling.

Thanks.

goksie
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/09ad06f7/attachment.html>

From kurt.alfred.mueller at gmail.com  Fri Jul  3 05:38:48 2009
From: kurt.alfred.mueller at gmail.com (yam850)
Date: Fri, 3 Jul 2009 02:38:48 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org> 
	<e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com>
Message-ID: <58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com>

On 1 Jul., 21:30, spillz <damienlmo... at gmail.com> wrote:
> On Jun 29, 3:15 pm, Pascal Chambon <chambon.pas... at gmail.com> wrote:
> > I've had real issues with subprocesses recently : from a python script,
> > on windows, I wanted to "give control" to a command line utility, i.e
> > forward user in put to it and display its output on console. It seems
> > simple, but I ran into walls :
> If you are willing to have a wxPython dependency, wx.Execute handles
> non-blockingi/o with processes on all supported platforms

I made a python method/function for non blocking read from a file
object.
I use it in one of my python programs.
When looking at the code bear in mind that I am not an expert and I am
happy to see comments.

#------------------------------------------------------------------
def non_blocking_readline(f_read=sys.stdin, timeout_select=0.0):
    """to readline non blocking from the file object 'f_read'
       for 'timeout_select' see module 'select'"""
    import select
    text_lines = ''                       # empty string
    while True:                           # as long as there are bytes
to read
        try:                              # try select
            rlist, wlist, xlist = select.select([f_read], [], [],
timeout_select)
        except:                           # select ERROR
            print >>sys.stderr, ("non_blocking_read select ERROR")
            break
        if DEBUG: print("rlist=%s, wlist=%s, xlist=%s" % (repr(rlist),
repr(wlist), repr(xlist)))
        if  len(rlist) > 0:
            text_read = f_read.readline() # get a line
            if DEBUG: print("after read/readline text_read:'%s', len=
%s" % (text_read, repr(len(text_read))))
            if  len(text_read) > 0:       # there were some bytes
                text_lines = "".join([text_lines, text_read])
                if DEBUG: print("text_lines:'%s'" % (text_lines))
            else:
                break                     # there was no byte in a
line
        else:
            break                         # there was no byte in the
f_read
    if  text_lines  ==  '':
        return None
    else:
        return text_lines


--
Kurt


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 05:50:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 09:50:09 GMT
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
	<025db26e$0$20657$c3e8da3@news.astraweb.com>
	<7xk52qgny8.fsf@ruckus.brouhaha.com>
Message-ID: <025dc5ec$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 01:39:27 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> groupby() works on lists.
> 
>>>> a = [1,3,4,6,7]
>>>> from itertools import groupby
>>>> b = groupby(a, lambda x: x%2==1)  # split into even and odd 
>>>> c = list(b)
>>>> print len(c)
> 3
>>>> d = list(c[1][1])    # should be [4,6] print d  # oops.
> []

I didn't say it worked properly *wink*

Seriously, this behaviour caught me out too. The problem isn't that the 
input data is a list, the same problem occurs for arbitrary iterators. 
>From the docs:

[quote]
The operation of groupby() is similar to the uniq filter in Unix. It 
generates a break or new group every time the value of the key function 
changes (which is why it is usually necessary to have sorted the data 
using the same key function). That behavior differs from SQL?s GROUP BY 
which aggregates common elements regardless of their input order.

The returned group is itself an iterator that shares the underlying 
iterable with groupby(). Because the source is shared, when the groupby() 
object is advanced, the previous group is no longer visible. So, if that 
data is needed later, it should be stored as a list
[end quote]

http://www.python.org/doc/2.6/library/itertools.html#itertools.groupby




-- 
Steven


From petshmidt at googlemail.com  Fri Jul  3 06:28:25 2009
From: petshmidt at googlemail.com (Tep)
Date: Fri, 3 Jul 2009 03:28:25 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
	<02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>
	<9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com> 
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>
Message-ID: <46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com>

On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> On Jul 2, 4:31?am, Tep <petshm... at googlemail.com> wrote:
>
>
>
>
>
> > On 2 Jul., 10:25, Tep <petshm... at googlemail.com> wrote:
>
> > > On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > > someone wrote:
> > > > > Hello,
>
> > > > > how can I replace '?' sign from string? Or do split at that character?
> > > > > Getting unicode error if I try to do it:
>
> > > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > > > > 1: ordinal not in range(128)
>
> > > > > Thanks, Pet
>
> > > > > script is # -*- coding: UTF-8 -*-
>
> > > > It sounds like you're mixing bytestrings with Unicode strings. I can't
> > > > be any more helpful because you haven't shown the code.
>
> > > Oh, I'm sorry. Here it is
>
> > > def cleanInput(input)
> > > ? ? return input.replace('?', '')
>
> > I also need:
>
> > #input is html source code, I have problem with only this character
> > #input = 'foo ? bar'
> > #return should be foo
> > def splitInput(input)
> > ? ? parts = input.split(' ? ')
> > ? ? return parts[0]
>
> > Thanks!
>
> Okay people want to help you but you must make it easy for us.
>
> Post again with a small piece of code that is runnable as-is and that
> causes the traceback you're talking about, AND post the complete
> traceback too, as-is.
>
> I just tried a bit of your code above in my interpreter here and it
> worked fine:
>
> |>>> data = 'foo ? bar'
> |>>> data.split('?')
> |['foo ', ' bar']
> |>>> data = u'foo ? bar'
> |>>> data.split(u'?')
> |[u'foo ', u' bar']
>
> Figure out the smallest piece of "html source code" that causes the
> problem and include that with your next post.

The problem was, I've converted "html source code" to unicode object
and didn't encoded to utf-8 back, before using split...
Thanks for help and sorry for not so smart question
Pet

>
> HTH,
> ~Simon
>
> You might also read this:http://catb.org/esr/faqs/smart-questions.html



From jeanmichel at sequans.com  Fri Jul  3 06:33:45 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 03 Jul 2009 12:33:45 +0200
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <4A4DDE89.1080003@sequans.com>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
>   
Easier for you but not for those who are familiar with the standard way 
of python coding. (by standard I don't mean the "only Godly way of 
coding", there's room for custom rules)
But I think most of the people will write:
if self.higher is None:
    return self.lower
if self.lower is None:
    return self.higher
# here neither are None

> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
>
> ## First snippet
>
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
>
> ## Second snippet
>
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
>
> What do you think?
>
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)
>   



From hkmshb at gmail.com  Fri Jul  3 06:46:32 2009
From: hkmshb at gmail.com (Klone)
Date: Fri, 3 Jul 2009 03:46:32 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
Message-ID: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>

Hi all. I believe in programming there is a common consensus to avoid
code duplication, I suppose such terms like 'DRY' are meant to back
this idea. Anyways, I'm working on a little project and I'm using TDD
(still trying to get a hang of the process) and am trying to test the
functionality within a method. Whoever it so happens to verify the
output from the method I have to employ the same algorithm within the
method to do the verification since there is no way I can determine
the output before hand.

So in this scenario is it OK to duplicate the algorithm to be tested
within the test codes or refactor the method such that it can be used
within test codes to verify itself(??).


From bthate at gmail.com  Fri Jul  3 06:50:36 2009
From: bthate at gmail.com (Bart Thate)
Date: Fri, 3 Jul 2009 03:50:36 -0700 (PDT)
Subject: GOZERBOT 0.9.1 BETA2 released
Message-ID: <67b84335-211d-4f7f-b417-71faeb70fbf5@o6g2000yqj.googlegroups.com>

GOZERBOT has a new website !! check it out at http://gozerbot.org.
This is all in preparation for the 0.9.1 release and the latest
GOZERBOT beta has been released as well. Please try this version and
let me know how goes.

Install is as simple as .. easy_install gozerbot gozerplugs, see
README.

This release will be used to move GOZERBOT 0.9 into the debian
repositories and freebsd ports.

we can be contacted on #dunkbots EFNET/IRCNET or use http://dev.gozerbot.org
for any bugs you might find.

NEW IN THIS RELEASE:

* GOZERBOT is now truely free as it no longer depends on GPL licensed
xmpppy, a own xmpp package has been implemented for this.

* GOZERBOT now depends on setuptools to install the proper packages

* gozerbot-nest script can be used to install all dependacies and bot
code in 1 directory that can be run by the user (no root required)

* morphs are added that allow for encryption of input and output
streams (not used yet)

ABOUT GOZERBOT:

GOZERBOT is a channel bot that aids with conversation in irc channels
and jabber conference rooms. its mainly used to serve rss feeds and to
have custom commands made for the channel. More then just a channel
bot GOZERBOT aims to provide a platform for the user to program his
own bot and make it into something thats usefull. This is done with a
plugin structure that makes it easy to program your own. But GOZERBOT
comes with some batteries included, there are now over 100 plugins
already written and ready for use.

groet,

Bart


From p.f.moore at gmail.com  Fri Jul  3 07:01:04 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Fri, 3 Jul 2009 12:01:04 +0100
Subject: Sequence splitting
In-Reply-To: <c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
Message-ID: <79990c6b0907030401w2e668ac3qd315c751d9e3e924@mail.gmail.com>

2009/7/3 Brad <schickb at gmail.com>:
> Perhaps true, but it would be a nice convenience (for me) as a built-
> in written in either Python or C. Although the default case of a bool
> function would surely be faster.

The chance of getting this accepted as a builtin is essentially zero.
To be a builtin, as opposed to being in the standard library,
something has to have a very strong justification.

This suggestion may find a home in the standard library, although it's
not entirely clear where (maybe itertools, although it's not entirely
obvious that it's a fit there).

You'd have to justify this against the argument "not every 2-3 line
function needs to be built in". Personally, I'm not sure it passes
that test - sure, it's a useful function, but it's not that hard to
write when you need it. It may be better as a recipe in the cookbook.
Or if it's close enough to the spirit of the itertools, it may be
suitable as a sample in the itertools documentation (the "recipes"
section).

Paul.


From user at example.net  Fri Jul  3 07:21:12 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 13:21:12 +0200
Subject: stringio+tarfile
In-Reply-To: <mailman.2533.1246588607.8015.python-list@python.org>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<mailman.2533.1246588607.8015.python-list@python.org>
Message-ID: <4a4de9a8$0$1105$4fafbaef@reader3.news.tin.it>

> First problem I see is all those numbers before the lines.  That's not 
> valid python.
> 
> Assuming that was a transcription error

not so. i intentionally add linenumbers to facilitare reference to the 
code, but if it is a nuisance i will not include them anymore.

thanks


From tkjthingone at gmail.com  Fri Jul  3 07:28:47 2009
From: tkjthingone at gmail.com (Horace Blegg)
Date: Fri, 3 Jul 2009 04:28:47 -0700
Subject: pep 8 constants
In-Reply-To: <BN23m.2219$ze1.1708@news-server.bigpond.net.au>
References: <mailman.7174.1231915778.3487.python-list@python.org>
	<49a50517$0$3567$426a74cc@news.free.fr> <4A477991.4050109@harvee.org>
	<op.uv89h1xqa8ncjz@gnudebst> <4A484C07.9050800@harvee.org>
	<4A48A495.7040504@tim.thechases.com> <4A48E307.50804@harvee.org>
	<4A49E232.6090101@tim.thechases.com>
	<mailman.2392.1246375713.8015.python-list@python.org>
	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>
Message-ID: <b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>

I've been kinda following this. I have a cousin who is permanently wheel
chair bound and doesn't have perfect control of her hands, but still manages
to use a computer and interact with society. However, the idea/thought of
disabled programmers was new to me/hadn't ever occurred to me.

You say that using your hands is painful, but what about your feet? Wouldn't
it be possible to rig up some kind of foot peddle for shift/caps lock? Kinda
like the power peddle used with sowing machines, so the hands are free to
hold fabric.

I don't mean this in a condescending manor, and I apologize if you take it
as such. I'm genuinely curious if you think something like this could work.

The way I was envisioning it working last night (and I haven't the faintest
clue how SR works, nor have I ever used SR) was that you would hit the foot
peddle, which would tell the SR program to capitalize the first letter of
the next word (a smart shift, basically, so you don't end up doing something
like ... WONderland -or- "stocks are up 1,0))% TOday".)

Possible? Stupid?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/d558cf34/attachment.html>

From ricli85 at gmail.com  Fri Jul  3 07:29:44 2009
From: ricli85 at gmail.com (Rickard Lindberg)
Date: Fri, 3 Jul 2009 13:29:44 +0200
Subject: Is code duplication allowed in this instance?
In-Reply-To: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <890d8ab70907030429i615c4bdat2263ac9555bd8c4e@mail.gmail.com>

> Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine
> the output before hand.

Can you clarify this scenario a bit?

If you are performing black-box testing I don't see why you need to
use the same algorithm in the test code. But maybe your case is
special. On the other hand you can not perform black-box testing if
the output is not known for a given input.

-- 
Rickard Lindberg


From user at example.net  Fri Jul  3 07:29:52 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 13:29:52 +0200
Subject: stringio+tarfile
In-Reply-To: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <4a4debb1$0$1106$4fafbaef@reader3.news.tin.it>

thanks to the guys who bothered to answer me even using their chrystal 
ball ;-)

i'll try to be more specific.

yes: i want to create a tar file in memory, and add some content from a
memory buffer...

my platform:

$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
$ python -V
Python 2.3.4

following some suggestions i modified the code:

$ cat tar001.py
import tarfile
import StringIO
sfo1 = StringIO.StringIO("one\n")
sfo2 = StringIO.StringIO("two\n")
tfo = StringIO.StringIO()
tar = tarfile.open(fileobj=tfo , mode="w")
ti = tar.gettarinfo(fileobj=tfo)
for sfo in [sfo1 , sfo2]:
     tar.addfile(fileobj=sfo , tarinfo=ti)
print tfo

and that's what i get:

$ python tar001.py > tar001.out
Traceback (most recent call last):
   File "tar001.py", line 7, in ?
     ti = tar.gettarinfo(fileobj=tfo)
   File "/usr/lib/python2.3/tarfile.py", line 1060, in gettarinfo
     name = fileobj.name
AttributeError: StringIO instance has no attribute 'name'

can you help?

TIA

ps: i'd also like that the tar file has names for the buffers, so than 
once output the file can be untarred with /bin/tar into regular files...


From eckhardt at satorlaser.com  Fri Jul  3 07:58:44 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Fri, 03 Jul 2009 13:58:44 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
Message-ID: <kc81i6-l85.ln1@satorlaser.homedns.org>

Thanks to all that answered, in particular I wasn't aware of the existence
of the __del__ function.

For completeness' sake, I think I have found another way to not really solve
but at least circumvent the problem: weak references. If I understand
correctly, those would allow me to pass out handles to the resources and,
if some code decides it is time, release the resources and render all the
weak references invalid. At least I don't suffer resource leaks but rather
get meaningful errors that way, which is enough for my case.

cheers!

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From __peter__ at web.de  Fri Jul  3 08:12:38 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 03 Jul 2009 14:12:38 +0200
Subject: stringio+tarfile
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<4a4debb1$0$1106$4fafbaef@reader3.news.tin.it>
Message-ID: <h2ksj9$g38$00$1@news.t-online.com>

superpollo wrote:

> thanks to the guys who bothered to answer me even using their chrystal
> ball ;-)
> 
> i'll try to be more specific.
> 
> yes: i want to create a tar file in memory, and add some content from a
> memory buffer...
> 
> my platform:
> 
> $ uname -a
> Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
> $ python -V
> Python 2.3.4
> 
> following some suggestions i modified the code:
> 
> $ cat tar001.py
> import tarfile
> import StringIO
> sfo1 = StringIO.StringIO("one\n")
> sfo2 = StringIO.StringIO("two\n")
> tfo = StringIO.StringIO()
> tar = tarfile.open(fileobj=tfo , mode="w")
> ti = tar.gettarinfo(fileobj=tfo)

gettarinfo() expects a real file, not a file-like object.
You have to create your TarInfo manually.

> for sfo in [sfo1 , sfo2]:
>      tar.addfile(fileobj=sfo , tarinfo=ti)
> print tfo
> 
> and that's what i get:
> 
> $ python tar001.py > tar001.out
> Traceback (most recent call last):
>    File "tar001.py", line 7, in ?
>      ti = tar.gettarinfo(fileobj=tfo)
>    File "/usr/lib/python2.3/tarfile.py", line 1060, in gettarinfo
>      name = fileobj.name
> AttributeError: StringIO instance has no attribute 'name'
> 
> can you help?

I recommend that you have a look into the tarfile module's source code.

The following seems to work:

import sys
import time
import tarfile
import StringIO

sf1 = "first.txt", StringIO.StringIO("one one\n")
sf2 = "second.txt", StringIO.StringIO("two\n")
tf = StringIO.StringIO()

tar = tarfile.open(fileobj=tf , mode="w")

mtime = time.time()
for name, f in [sf1 , sf2]:
    ti = tarfile.TarInfo(name)
    ti.size = f.len
    ti.mtime = mtime
    # add more attributes as needed 
    tar.addfile(ti, f)

sys.stdout.write(tf.getvalue())

Peter



From sri_annauni at yahoo.co.in  Fri Jul  3 08:15:47 2009
From: sri_annauni at yahoo.co.in (srinivasan srinivas)
Date: Fri, 3 Jul 2009 17:45:47 +0530 (IST)
Subject: Python debugger
Message-ID: <740981.83964.qm@web7901.mail.in.yahoo.com>


Hi,
Could you suggest some python debuggers?

Thanks,
Srini


      Love Cricket? Check out live scores, photos, video highlights and more. Click here http://cricket.yahoo.com


From jackdied at gmail.com  Fri Jul  3 08:34:01 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Fri, 3 Jul 2009 08:34:01 -0400
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>
Message-ID: <b8e622740907030534s7f57d686g9f4eb956962bef00@mail.gmail.com>

On Thu, Jul 2, 2009 at 2:36 PM, Carl Banks<pavlovevidence at gmail.com> wrote:
> On Jul 2, 3:12?am, Ulrich Eckhardt <eckha... at satorlaser.com> wrote:
>> Bearophile wrote:
>> > Ulrich Eckhardt:
>> >> a way to automatically release the resource, something
>> >> which I would do in the destructor in C++.
>>
>> > Is this helpful?
>> >http://effbot.org/pyref/with.htm
>>
>> Yes, it aims in the same direction. However, I'm not sure this applies to my
>> case. The point is that the resource handle is not just used locally in a
>> restricted scope but it is allocated and stored. The 'with' is something
>> that makes sense in the context of mutex locking, where you have a
>> well-defined critical section. What I need is something similar to open(),
>> which returs a file. When the last reference to that object goes out of
>> scope, the underlying file object is closed.
>
> On CPython you can do it with a __del__ attribute.
>
> Warning: objects with a __del__ attribute prevent reference cycle
> detection, which can potentially lead to memory (and resource) leaks.
> So you must be careful to avoid creating reference loops with that
> object.

WARNING-er: As Carl points out, adding a __del__ method actually makes
it /less/ likely that your object will be cleaned up.  __del__ is only
useful if you have a complicated tear-down procedure.  Since you come
from C++ RAII land (my old haunt) your objects probably only allocate
one resource each, or worse: a bunch of objects that allocate one
resource each.  In that case __del__ will always hurt you.

The C++ temptation is to match every __init__ with a __del__.  A
better rule of thumb is to only add a __del__ method after confirming
with someone else that it would be useful.  Better still is to ask
them by postal courier.  For best results that someone should be your
grandmother.

> Note that file objects have a close method; you can explicitly close
> it at any time. ?Your object should follow that example, and define a
> close (or release, or whatever) method. ?I'd recommend making an
> effort to call it and to rely on __del__ as little as possible.

This.  If you care enough about a resource to write a __del__ method
you care enough to clean it up explicitly.  'with' blocks are very
nice for that.


-jack


From tn.pablo at gmail.com  Fri Jul  3 08:34:20 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Fri, 3 Jul 2009 07:34:20 -0500
Subject: Sequence splitting
In-Reply-To: <79990c6b0907030401w2e668ac3qd315c751d9e3e924@mail.gmail.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<79990c6b0907030401w2e668ac3qd315c751d9e3e924@mail.gmail.com>
Message-ID: <fdd00b510907030534j1cbfb11dx72b52c6265452dbe@mail.gmail.com>

On Fri, Jul 3, 2009 at 06:01, Paul Moore<p.f.moore at gmail.com> wrote:
> 2009/7/3 Brad <schickb at gmail.com>:
>> Perhaps true, but it would be a nice convenience (for me) as a built-
>> in written in either Python or C. Although the default case of a bool
>> function would surely be faster.
>
> The chance of getting this accepted as a builtin is essentially zero.
> To be a builtin, as opposed to being in the standard library,
> something has to have a very strong justification.

That's right.  Mr. schickb, I think what you need is a few concrete
examples as to where this function would be beneficial, so it can be
judged objectively.

-- 
Pablo Torres N.


From bieffe62 at gmail.com  Fri Jul  3 08:34:27 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Fri, 3 Jul 2009 05:34:27 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <b0b2ff61-9023-474c-b114-863107781971@y7g2000yqa.googlegroups.com>

On Jul 3, 12:46?pm, Klone <hkm... at gmail.com> wrote:
> Hi all. I believe in programming there is a common consensus to avoid
> code duplication, I suppose such terms like 'DRY' are meant to back
> this idea. Anyways, I'm working on a little project and I'm using TDD
> (still trying to get a hang of the process) and am trying to test the
> functionality within a method. Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine
> the output before hand.
>
> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

If the purpose of the test is to verify the algorithm, you obviously
should not use the algorithm
to verify itself ... you should use a  set of pairs (input data,
exoected output data) data that you know is
well representative of the data your algorithm will process. Possibly
to prepare the test data set
you might need a  different - and already proven - implementation of
the algorithm.

Another thing I sometime do when testing mathematics function is use
counter-proof: for instance, if my function
computes the roots of a quadratic equation, the test verifies that the
roots applied to the equation
actually give (almost) zero as result. This kind of test might not be
as rigorous as preparing the data set with the known
answers, but it is easier to setup and could give you a first idea if
your code is "correct enough" to stand
more formal proof.

Ciao
----
FB


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 08:46:08 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 14:46:08 +0200
Subject: Python debugger
In-Reply-To: <mailman.2555.1246623750.8015.python-list@python.org>
References: <mailman.2555.1246623750.8015.python-list@python.org>
Message-ID: <4a4dfd78$0$404$426a74cc@news.free.fr>

srinivasan srinivas a ?crit :
> Hi,
> Could you suggest some python debuggers?

http://docs.python.org/library/pdb.html#module-pdb

HTH


From lie.1296 at gmail.com  Fri Jul  3 08:49:21 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 12:49:21 GMT
Subject: Is code duplication allowed in this instance?
In-Reply-To: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <l7n3m.2388$ze1.2120@news-server.bigpond.net.au>

Klone wrote:
> Hi all. I believe in programming there is a common consensus to avoid
> code duplication, I suppose such terms like 'DRY' are meant to back
> this idea. Anyways, I'm working on a little project and I'm using TDD
> (still trying to get a hang of the process) and am trying to test the
> functionality within a method. Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine
> the output before hand.
> 
> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

When unittesting a complex output, usually the first generation code
would generate the output and then you (manually) verify this output and
copy the output to the test code. The testing code should be as dumb as
possible to avoid bugs in the testing code itself. The most important
thing is not to use a possibly buggy algorithm implementation to check
the algorithm itself. If your test code looks like this:

# this the function to be tested
def func(a, b):
    return a + b

class TC(unittest.TestCase):
    def test_foo(self):
        a, b = 10, 20 # worse: use random module
        result = a + b
        self.assertEqual(func(a, b), result)

then something is definitely wrong. Instead the testing code should be
simple and stupid like:

class TC(unittest.TestCase):
    def test_foo(self):
        self.assertEqual(func(10, 20), 30)

There are exceptions though, such as if you're 100% sure your
first-generation program is correct and you simply want to replicate the
same function with different algorithm, or probably optimizing the
function. For that case, you could do something like this:

def func(a, b):
    # some fancy new algo
    pass
class TC(unittest.TestCase):
    def original_func(self, a, b):
        return a + b
    def test_foo(self):
        self.assertEquals(func(a, b), self.original_func(a, b))


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 08:50:10 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 14:50:10 +0200
Subject: Adding an object to the global namespace through " f_globals"
	is that allowed ?
In-Reply-To: <mailman.2452.1246493871.8015.python-list@python.org>
References: <mailman.2452.1246493871.8015.python-list@python.org>
Message-ID: <4a4dfe6a$0$404$426a74cc@news.free.fr>

Stef Mientki a ?crit :
> hello,
> 
> I need to add an object's name to the global namespace.
> The reason for this is to create an environment,
> where you can add some kind of math environment,
> where no need for Python knowledge is needed.
> 
> The next statement works,
> but I'm not sure if it will have any dramatical side effects,
> other than overruling a possible object with the name A
> 
> def some_function ( ...) :
>      A = object ( ...)
>      sys._getframe(1).f_globals [ Name ] = A
> 
> 

Anything wrong with the 'global' statement ?

Python 2.5.2 (r252:60911, Oct  5 2008, 19:24:49)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
pythonrc start
pythonrc done
 >>> def foo():
...     global a
...     a = 42
...
 >>> a
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
NameError: name 'a' is not defined
 >>> foo()
 >>> a
42
 >>>




From ziade.tarek at gmail.com  Fri Jul  3 08:57:19 2009
From: ziade.tarek at gmail.com (=?ISO-8859-1?Q?Tarek_Ziad=E9?=)
Date: Fri, 3 Jul 2009 14:57:19 +0200
Subject: PEP 376
In-Reply-To: <EF743CC8-5AFE-47F5-97A9-AF993BD4B6C7@declareSub.com>
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net> <4A4C685A.8020300@Strombergson.com>
	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
	<1f63m.2229$ze1.1410@news-server.bigpond.net.au>
	<EF743CC8-5AFE-47F5-97A9-AF993BD4B6C7@declareSub.com>
Message-ID: <94bdd2610907030557q79cf7018t77c39beb6f45437b@mail.gmail.com>

Ok here's my proposal for the checksum :

- I'll add the "hash_type:" suffix in the record file

- install will get a new option to define what hash should be used
when writing the RECORD file
  it will default to SHA1 for 2.7/3.2

- pkgutil, that reads the RECORD files, will pick the right hash
function by looking at the suffix

now for the security it's another story that goes beyond the scope of this PEP
notice though, that the PEP provides a place-holder for distributions metadata,
so it could host a key later on.


On Thu, Jul 2, 2009 at 8:00 PM, Charles Yeomans<charles at declaresub.com> wrote:
>
> On Jul 2, 2009, at 1:37 PM, Lie Ryan wrote:
>
>> Joachim Str?mbergson wrote:
>>>
>>> Aloha!
>>>
>>> Tarek Ziad? wrote:
>>>>
>>>> The prefix is a good idea but since it's just a checksum to control
>>>> that the file hasn't changed
>>>> what's wrong with using a weak hash algorithm like md5 or now sha1 ?
>>>
>>> Because it creates a dependency to an old algorithm that should be
>>> deprecated. Also using MD5, even for a thing like this might make people
>>> belive that it is an ok algorithm to use - "Hey, it is used by the
>>> default install in Python, so it must be ok, right?"
>>>
>>> If we flip the argument around: Why would you want to use MD5 instead of
>>> SHA-256? For the specific use case the performance will not (should not)
>>> be an issue.
>>>
>>> As I wrote a few mails ago, it is time to move forward from MD5 and
>>> designing something in 2009 that will be around for many years that uses
>>> MD5 is (IMHO) a bad design decision.
>>>
>>>> If someone wants to modify a file of a distribution he can recreate
>>>> the checksum as well,
>>>> the only secured way to prevent that would be to use gpg keys but
>>>> isn't that overkill for what we need ?
>>>
>>> Actually, adding this type of security would IMHO be a good idea.
>>>
>>
>> Now, are we actually talking about security or checksum?
>>
>> It has been known for years that MD5 is weak, weak, weak. Not just in
>> the recent years. But it doesn't matter since MD5 was never designed for
>> security, MD5 was designed to protect against random bits corruption. If
>> you want security, look at least to GPG. For data protection against
>> intentional, malicious forging, definitely MD5 is the wrong choice. But
>> when you just want a simple checksum to ensure that a faulty router
>> somewhere in the internet backbone doesn't destroying your data, MD5 is
>> a fine algorithm.
>> --
>
> On the contrary, MD5 was intended to be a cryptographic hash function, not a
> checksum.
>
> Charles Yeomans
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Tarek Ziad? | http://ziade.org


From nosklo at gmail.com  Fri Jul  3 08:57:35 2009
From: nosklo at gmail.com (Clovis Fabricio)
Date: Fri, 3 Jul 2009 09:57:35 -0300
Subject: Python debugger
In-Reply-To: <740981.83964.qm@web7901.mail.in.yahoo.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
Message-ID: <9187a60d0907030557q69a2429cn509e3792ed7708be@mail.gmail.com>

2009/7/3 srinivasan srinivas <sri_annauni at yahoo.co.in>:
> Could you suggest some python debuggers?

Two graphical debugger frontends:

http://www.gnu.org/software/emacs/
http://winpdb.org/


From lie.1296 at gmail.com  Fri Jul  3 09:10:34 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 13:10:34 GMT
Subject: Sequence splitting
In-Reply-To: <h2khkq$159j$1@adenine.netfront.net>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
	<nfi3m.2341$ze1.1151@news-server.bigpond.net.au>
	<h2khkq$159j$1@adenine.netfront.net>
Message-ID: <ern3m.2390$ze1.651@news-server.bigpond.net.au>

tsangpo wrote:
> Just a shorter implementation:
> 
> from itertools import groupby
> def split(lst, func):
>     gs = groupby(lst, func)
>     return list(gs[True]), list(gs[False])
> 

As you're replying to my post, I assume you meant a shorter
implementation my function. But it doesn't do the same thing. The idea
with my group() is similar to what Steven D'Aprano is describing in
another branch of this thread (i.e. splitting not only based on True and
False, but arbitrary groupings, e.g. 'tru', 'flash' or perhaps -1, 0, 1).

For example:
>>> def group(seq, func=bool):
...     ret = {}
...     for item in seq:
...         fitem = func(item)
...         try:
...             ret[fitem].append(item)
...         except KeyError:
...             ret[fitem] = [item]
...     return ret
...
>>> group(range(10), lambda x: x%3)
{0: [0, 3, 6, 9], 1: [1, 4, 7], 2: [2, 5, 8]}
>>> # the next one is the OP's split
>>> group(['true', '', [], [''], 'false'], bool)
{False: ['', []], True: ['true', [''], 'false']}


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 09:11:00 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 13:11:00 GMT
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <025df4fd$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 03:46:32 -0700, Klone wrote:

> Hi all. I believe in programming there is a common consensus to avoid
> code duplication, I suppose such terms like 'DRY' are meant to back this
> idea. Anyways, I'm working on a little project and I'm using TDD (still
> trying to get a hang of the process) and am trying to test the
> functionality within a method. Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine the
> output before hand.
> 
> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

Neither -- that's essentially a pointless test. The only way to 
*correctly* test a function is to compare the result of that function to 
an *independent* test. If you test a function against itself, of course 
it will always pass:

def plus_one(x):
    """Return x plus 1."""
    return x-1  # Oops, a bug.

# Test it is correct:
assert plus_one(5) == plus_one(5)


The only general advice I can give is:

(1) Think very hard about finding an alternative algorithm to calculate 
the same result. There usually will be one.

(2) If there's not, at least come up with an alternative implementation. 
It doesn't need to be particularly efficient, because it will only be 
called for testing. A rather silly example:

def plus_one_testing(x):
    """Return x plus 1 using a different algorithm for testing."""
    if type(x) in (int, long):
        temp = 1
        for i in range(x-1):
            temp += 1
        return temp
    else:
        floating_part = x - int(x)
        return floating_part + plus_one_testing(int(x))

(The only problem is, if a test fails, you may not be sure whether it's 
because your test function is wrong or your production function.)

(3) Often you can check a few results by hand. Even if it takes you 
fifteen minutes, at least that gives you one good test. If need be, get a 
colleague to check your results.

(4) Test failure modes. It might be really hard to calculate func(arg) 
independently for all possible arguments, but if you know that func(obj) 
should fail, at least you can test that. E.g. it's hard to test whether 
or not you've downloaded the contents of a URL correctly without actually 
downloading it, but you know that http://example.com/ should fail because 
that domain doesn't exist.

(5) Test the consequences of your function rather than the exact results. 
E.g. if it's too difficult to calculate plus_one(x) independently:

assert plus_one(x) > x  # except for x = inf or -inf
assert plus_one( -plus_one(x) ) == x  # -(x+1)+1 = x

(6) While complete test coverage is the ideal you aspire to, any tests 
are better than no tests. But they have to be good tests to be useful. 
Even *one* test is better than no tests.



Hope this helps.



-- 
Steven


From lie.1296 at gmail.com  Fri Jul  3 09:16:00 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 13:16:00 GMT
Subject: stringio+tarfile
In-Reply-To: <4a4de9a8$0$1105$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<mailman.2533.1246588607.8015.python-list@python.org>
	<4a4de9a8$0$1105$4fafbaef@reader3.news.tin.it>
Message-ID: <kwn3m.2391$ze1.2254@news-server.bigpond.net.au>

superpollo wrote:
>> First problem I see is all those numbers before the lines.  That's not
>> valid python.
>>
>> Assuming that was a transcription error
> 
> not so. i intentionally add linenumbers to facilitare reference to the
> code, but if it is a nuisance i will not include them anymore.

The line numbering makes it impossible for others to copy and paste to
the interactive interpreter to see the problem code running, and makes
it hard to copy and paste into a script file. For code reference,
quoting the problematic code is usually much easier.


From ronn.ross at gmail.com  Fri Jul  3 09:26:52 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Fri, 3 Jul 2009 09:26:52 -0400
Subject: VirtualEnv
Message-ID: <9c8c445f0907030626i62d912e6k6d92247a428145e0@mail.gmail.com>

I'm attempting to write a bootstrap script for virtualenv. I just want to do
a couple of easy_install's after the environment is created. It was fairly
easy to create the script, but I can't figure out how to implement it. The
documentation was not of much help. Can someone please point me in the right
direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/08a6bbe0/attachment.html>

From no.email at please.post  Fri Jul  3 09:38:20 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 13:38:20 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2l1kc$2tj$1@reader1.panix.com>

In <025db0a6$0$20657$c3e8da3 at news.astraweb.com> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:

>On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:

>> If the concern is efficiency for such cases, then simply implement
>> optional offset and length parameters for re.search(), to specify any
>> arbitrary substring to apply the search to.  To have a special-case
>> re.match() method in addition to a general re.search() method is
>> antithetical to language minimalism, and plain-old bizarre.  Maybe
>> there's a really good reason for it, but it has not been mentioned yet.

>There is, and it has.

I "misspoke" earlier.  I should have written "I'm *sure* there's
a really good reason for it."  And I think no one in this thread
(myself included, of course) has a clue of what it is.  I miss the
days when Guido still posted to comp.lang.python.  He'd know. 

Regarding the "practicality beats purity" line, it's hard to think
of a better motto for *Perl*, with all its practicality-oriented
special doodads.  (And yes, I know where the "practicality beats
purity" line comes from.)  Even *Perl* does not have a special
syntax for the task that re.match is supposedly tailor-made for,
according to the replies I've received.  Given that it is so trivial
to implement all of re.match's functionality with only one additional
optional parameter for re.search (i.e. pos), it is absurd to claim
that re.match is necessary for the sake of this special functionality.
The justification for re.match must be elsewhere.

But thanks for letting me know that I'm entitled to my opinion.
That's a huge relief.

kj



From python at mrabarnett.plus.com  Fri Jul  3 09:53:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 14:53:42 +0100
Subject: Why re.match()?
In-Reply-To: <h2l1kc$2tj$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
	<h2l1kc$2tj$1@reader1.panix.com>
Message-ID: <4A4E0D66.6070704@mrabarnett.plus.com>

kj wrote:
> In <025db0a6$0$20657$c3e8da3 at news.astraweb.com> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> 
>> On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:
> 
>>> If the concern is efficiency for such cases, then simply implement
>>> optional offset and length parameters for re.search(), to specify any
>>> arbitrary substring to apply the search to.  To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism, and plain-old bizarre.  Maybe
>>> there's a really good reason for it, but it has not been mentioned yet.
> 
>> There is, and it has.
> 
> I "misspoke" earlier.  I should have written "I'm *sure* there's
> a really good reason for it."  And I think no one in this thread
> (myself included, of course) has a clue of what it is.  I miss the
> days when Guido still posted to comp.lang.python.  He'd know. 
> 
> Regarding the "practicality beats purity" line, it's hard to think
> of a better motto for *Perl*, with all its practicality-oriented
> special doodads.  (And yes, I know where the "practicality beats
> purity" line comes from.)  Even *Perl* does not have a special
> syntax for the task that re.match is supposedly tailor-made for,
> according to the replies I've received.  Given that it is so trivial
> to implement all of re.match's functionality with only one additional
> optional parameter for re.search (i.e. pos), it is absurd to claim
> that re.match is necessary for the sake of this special functionality.
> The justification for re.match must be elsewhere.
> 
> But thanks for letting me know that I'm entitled to my opinion.
> That's a huge relief.
> 
As I wrote, re.match anchors the match whereas re.search doesn't. An
alternative would have been to implement Perl's \G anchor, but I believe
that that was invented after the re module was written.


From no.email at please.post  Fri Jul  3 10:05:08 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 14:05:08 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
Message-ID: <h2l36k$q5l$1@reader1.panix.com>



I'm will be teaching a programming class to novices, and I've run
into a clear conflict between two of the principles I'd like to
teach: code clarity vs. code reuse.  I'd love your opinion about
it.

The context is the concept of a binary search.  In one of their
homeworks, my students will have two occasions to use a binary
search.  This seemed like a perfect opportunity to illustrate the
idea of abstracting commonalities of code into a re-usable function.
So I thought that I'd code a helper function, called _binary_search,
that took five parameters: a lower limit, an upper limit, a
one-parameter function, a target value, and a tolerance (epsilon).
It returns the value of the parameter for which the value of the
passed function is within the tolerance of the target value.

This seemed straightforward enough, until I realized that, to be
useful to my students in their homework, this _binary_search function
had to handle the case in which the passed function was monotonically
decreasing in the specified interval...

The implementation is still very simple, but maybe not very clear,
particularly to programming novices (docstring omitted):

def _binary_search(lo, hi, func, target, epsilon):
    assert lo < hi
    assert epsilon > 0
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    target_plus = sense * target + epsilon
    target_minus = sense * target - epsilon
    while True:
        param = (lo + hi) * 0.5
        value = sense * func(param)
        if value > target_plus:
            hi = param
        elif value < target_minus:
            lo = param
        else:
            return param

	if lo == hi:
	    return None

My question is: is the business with sense and cmp too "clever"?

Here's the rub: the code above is more general (hence more reusable)
by virtue of this trick with the sense parameter, but it is also
a bit harder to understand.

This not an unusual situation.  I find that the processing of
abstracting out common logic often results in code that is harder
to read, at least for the uninitiated...

I'd love to know your opinions on this.

TIA!

kj



From esj at harvee.org  Fri Jul  3 10:19:10 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Fri, 03 Jul 2009 10:19:10 -0400
Subject: pep 8 constants
In-Reply-To: <b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>
	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>
	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>
	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
Message-ID: <4A4E135E.5090400@harvee.org>

Horace Blegg wrote:
> I've been kinda following this. I have a cousin who is permanently wheel
> chair bound and doesn't have perfect control of her hands, but still
> manages to use a computer and interact with society. However, the
> idea/thought of disabled programmers was new to me/hadn't ever occurred
> to me.
> 
> You say that using your hands is painful, but what about your feet?
> Wouldn't it be possible to rig up some kind of foot peddle for
> shift/caps lock? Kinda like the power peddle used with sowing machines,
> so the hands are free to hold fabric.
> 
> I don't mean this in a condescending manor, and I apologize if you take
> it as such. I'm genuinely curious if you think something like this could
> work.
> 
> The way I was envisioning it working last night (and I haven't the
> faintest clue how SR works, nor have I ever used SR) was that you would
> hit the foot peddle, which would tell the SR program to capitalize the
> first letter of the next word (a smart shift, basically, so you don't
> end up doing something like ... WONderland -or- "stocks are up 1,0))%
> TOday".)
> 
> Possible? Stupid?
> 
it's not stupid.

People have used foot pedals for decades for a variety of controls. I don't
think foot pedals would work for me because when I am dictating, I pace.
Standing, sitting, I pace. With a cord headset, I'm forced to stay within about
4 feet of the computer. But what I'm using a Bluetooth headset, I will sometimes
ramble as far as 10 or 15 feet from the computer. It helps if I make the font
larger so I can glance over and see what kind of errors I've gotten.

I really love a Bluetooth headset with speech recognition. It's so liberating.

Your question about foot pedals makes me think of alternative. would it make
sense to have a handheld keyboard which would be used for command-and-control
functionality or as an adjunct to speech recognition use? It would have to be
designed in such a way that it doesn't aggravate a hand injury which may not be
possible. Anyway, just thinking out loud.



From aahz at pythoncraft.com  Fri Jul  3 10:31:36 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 07:31:36 -0700
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com> <h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
	<h2l1kc$2tj$1@reader1.panix.com>
Message-ID: <h2l4o8$sn3$1@panix3.panix.com>

In article <h2l1kc$2tj$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>In <025db0a6$0$20657$c3e8da3 at news.astraweb.com> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>>On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:
>>>
>>> If the concern is efficiency for such cases, then simply implement
>>> optional offset and length parameters for re.search(), to specify any
>>> arbitrary substring to apply the search to.  To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism, and plain-old bizarre.  Maybe
>>> there's a really good reason for it, but it has not been mentioned yet.
>>
>>There is, and it has.
>
>I "misspoke" earlier.  I should have written "I'm *sure* there's
>a really good reason for it."  And I think no one in this thread
>(myself included, of course) has a clue of what it is.  I miss the
>days when Guido still posted to comp.lang.python.  He'd know. 

You may find this enlightening:

http://www.python.org/doc/1.4/lib/node52.html
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 10:33:12 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 14:33:12 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <025e0841$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 14:05:08 +0000, kj wrote:

> ... I find that the processing of
> abstracting out common logic often results in code that is harder to
> read ...

Yes. There is often a conflict between increasing abstraction and ease of 
understanding.



[...]
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
> 
> def _binary_search(lo, hi, func, target, epsilon):
>     assert lo < hi
>     assert epsilon > 0

You're using assert for data sanitation. That is a very bad habit for you 
to be teaching novices. Your code will fail to behave as expected 
whenever the caller runs Python with the -O switch.


[...]
> My question is: is the business with sense and cmp too "clever"?

For production code? Maybe -- you would need to profile the code, and 
compare it to a less general, more simple-minded function, and see which 
performs better. If there is an excessive performance penalty, that's a 
good sign that perhaps you're being too clever, too general, or too 
abstract -- or all three.

Too clever for novices? That depends on how inexperienced they are -- are 
they new to Python or new to programming in general? Are they children or 
adults? Do they have a PhD degree or are they still at primary school? It 
depends on their experience and their intelligence -- dare I say it, some 
people will *never* get programming, let alone code-reuse. It also 
depends on how you lead up to it -- are you dropping them straight into 
the abstract code, or giving them two pieces of nearly the same code and 
showing them how to pull out the common functionality?


-- 
Steven


From bearophileHUGS at lycos.com  Fri Jul  3 10:34:23 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 3 Jul 2009 07:34:23 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
	<b0b2ff61-9023-474c-b114-863107781971@y7g2000yqa.googlegroups.com>
Message-ID: <4d99b710-45f1-42dc-b80c-1894af26db42@p29g2000yqh.googlegroups.com>

Francesco Bochicchio:
> Possibly to prepare the test data set you might need a
> different - and already proven - implementation of
> the algorithm.

Usually a brute force or slow but short algorithm is OK (beside some
hard-coded input-output pairs).

Sometimes you may use the first implementation of your code that's
usually simpler, before becoming complex because of successive
optimizations. But you have to be careful, because the first
implementation too may be buggy.

Some other times there are simpler algorithms to test if the output of
another algorithm is correct (think of exponential algorithms with a
polinomial test of the correct result), for example to test a fancy
Introsort implementation you can use a very small and simple O(n^2)
sorter, or better a simple linear loop that tests the result to be
sorted.

Here, beside unit tests, are also useful languages (or tools) that
allow to add pre- and post-conditions, class invariants, etc.

Bye,
bearophile


From alan.isaac at gmail.com  Fri Jul  3 10:34:58 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 14:34:58 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <mGo3m.591$P5.76@nwrddc02.gnilink.net>

On 7/3/2009 10:05 AM kj apparently wrote:
> The context is the concept of a binary search.  In one of their
> homeworks, my students will have two occasions to use a binary
> search.  This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.
> 
> This seemed straightforward enough, until I realized that, to be
> useful to my students in their homework, this _binary_search function
> had to handle the case in which the passed function was monotonically
> decreasing in the specified interval...
> 
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
> 
> def _binary_search(lo, hi, func, target, epsilon):
>     assert lo < hi
>     assert epsilon > 0
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
>     target_plus = sense * target + epsilon
>     target_minus = sense * target - epsilon
>     while True:
>         param = (lo + hi) * 0.5
>         value = sense * func(param)
>         if value > target_plus:
>             hi = param
>         elif value < target_minus:
>             lo = param
>         else:
>             return param
> 
> 	if lo == hi:
> 	    return None



1. Don't use assertions to test argument values!

2.
from scipy.optimize import bisect
def _binary_search(lo, hi, func, target, epsilon):
    def f(x): return func(x) - target
    return bisect(f, lo, high, xtol=epsilon)

3. If you don't want to use SciPy (why?), have them
implement http://en.wikipedia.org/wiki/Bisection_method#Pseudo-code
to produce their own `bisect` function.

hth,
Alan Isaac


From aahz at pythoncraft.com  Fri Jul  3 10:36:38 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 07:36:38 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <h2l51m$jps$1@panix3.panix.com>

In article <h2l36k$q5l$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>This seemed straightforward enough, until I realized that, to be
>useful to my students in their homework, this _binary_search function
>had to handle the case in which the passed function was monotonically
>decreasing in the specified interval...
>
>def _binary_search(lo, hi, func, target, epsilon):
>    assert lo < hi
>    assert epsilon > 0
>    sense = cmp(func(hi), func(lo))
>    if sense == 0:
>        return None
>    target_plus = sense * target + epsilon
>    target_minus = sense * target - epsilon
>    while True:
>        param = (lo + hi) * 0.5
>        value = sense * func(param)
>        if value > target_plus:
>            hi = param
>        elif value < target_minus:
>            lo = param
>        else:
>            return param
>
>	if lo == hi:
>	    return None
>
>My question is: is the business with sense and cmp too "clever"?

First of all, cmp() is gone in Python 3, unfortunately, so I'd avoid
using it.  Second, assuming I understand your code correctly, I'd change
"sense" to "direction" or "order".
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From timinganalyzer at gmail.com  Fri Jul  3 10:42:12 2009
From: timinganalyzer at gmail.com (chewie)
Date: Fri, 3 Jul 2009 07:42:12 -0700 (PDT)
Subject: The TimingAnalyzer  -- project to convert from Java to Python
Message-ID: <368b6501-5f01-4a96-9e31-274601878464@c36g2000yqn.googlegroups.com>

?Hello,

This a project related to the development of an EDA CAD tool program
called the TimingAnalyzer.  Digital engineers could use this kind of
program to analyze and document inteface timing diagrams  for IC,
ASIC, FPGA, and board level hardware projects.

The TimingAnalyzer is licensed as freeware.   I don't have the time
needed to make a high quality commercial product but I do want to keep
the development moving forward and continue to fix problems and add
new features as time permits.

www.timing-diagrams.com

Recently, I have become very interested in Python and using it to
develop similar type cad programs.  My plan is to convert the
TimingAnalyzer Java to Python with mostly a scripting interface for
building complex timing diagrams, doing timing analysis,  creating
testbenches and testvectors from waveform diagrams,
and creating timing diagrams from simulation VCD files.  Most all of
this is text based work anyway.

Developing professional GUIs is very time consuming for me.  This has
been my bottleneck with the program all along.  With a command line
interface,  you will execute a script and in one window,  and view and
edit and print the timing diagram shown in another window.   Like the
Matlab interface.

For example:

micro = m68000()
micro.write(add, data, wait_states)
micro.read(add, wait_states).

or

add_clock(......)
add_signal(.....)
add_delay(......)
add_constraint(.....)
add_or_gate(....)
add_and_gate(....)
add_counter(....)
add_clock_jitter(.....)

analyze_clock_domains(.....)
analyze_worst_case_timings(....)
analyze_best_case_timings.

read_vcd(....)
vcd_2_timing_diagram(.....)
create_testvectors(.....)
create_testbench(....)

A lot of these functions are built into the program now so its a
matter of converting them java to python.  I won't have to spend most
of the time getting the user interface to look good and be friendly.
If this is made an open source project,  I would hope that others
would help with the development and new features and bug fixes will so
progress will be made quickly.

If anyone is interested in helping with the development,  I will make
this an open source project.   Just let me know if your interested.

Thank you,
Dan Fabrizio


From bearophileHUGS at lycos.com  Fri Jul  3 10:48:57 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 3 Jul 2009 07:48:57 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <5461f308-3b3b-4baf-9ef0-c1a94d059119@y17g2000yqn.googlegroups.com>

On 3 Lug, 16:05, kj <no.em... at please.post> wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.

They are both important principles, but clarity is usually more
important because short code that can't be read can't be fixed and
modified, while long code that can be read is alive still.


> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).

Five arguments are a bit too much, even for non-novices. 2-3 arguments
are more than enough for novices.

Where are doctests'? Novices have to learn to think of tests as part
of the normal code :-)

I think the main problem in all this discussion is that generally to
learn to program you have to write code yourself, so your students
have to invent and write their own binary search. Reading your code
they are going to learn much less. Creating a binary search from
almost scratch can turn out to be too much hard for them, it means you
have to ask them to invent something simpler :-)

Programming is (among other things) problem solving, so they have to
learn to solve not easy problems from the beginning. Showing them
famous algorithms (and very good code to copy from) can be useful, but
it's less important than learning basic problem solving skills, and
much less important than learning why solving problems has to became
their purpose and pleasure :-)

Bye,
bearophile


From python at mrabarnett.plus.com  Fri Jul  3 10:52:31 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 15:52:31 +0100
Subject: pep 8 constants
In-Reply-To: <4A4E135E.5090400@harvee.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
	<4A4E135E.5090400@harvee.org>
Message-ID: <4A4E1B2F.2000700@mrabarnett.plus.com>

Eric S. Johansson wrote:
> Horace Blegg wrote:
>> I've been kinda following this. I have a cousin who is permanently wheel
>> chair bound and doesn't have perfect control of her hands, but still
>> manages to use a computer and interact with society. However, the
>> idea/thought of disabled programmers was new to me/hadn't ever occurred
>> to me.
>>
>> You say that using your hands is painful, but what about your feet?
>> Wouldn't it be possible to rig up some kind of foot peddle for
>> shift/caps lock? Kinda like the power peddle used with sowing machines,
>> so the hands are free to hold fabric.
>>
>> I don't mean this in a condescending manor, and I apologize if you take
>> it as such. I'm genuinely curious if you think something like this could
>> work.
>>
>> The way I was envisioning it working last night (and I haven't the
>> faintest clue how SR works, nor have I ever used SR) was that you would
>> hit the foot peddle, which would tell the SR program to capitalize the
>> first letter of the next word (a smart shift, basically, so you don't
>> end up doing something like ... WONderland -or- "stocks are up 1,0))%
>> TOday".)
>>
>> Possible? Stupid?
>>
> it's not stupid.
> 
> People have used foot pedals for decades for a variety of controls. I don't
> think foot pedals would work for me because when I am dictating, I pace.
> Standing, sitting, I pace. With a cord headset, I'm forced to stay within about
> 4 feet of the computer. But what I'm using a Bluetooth headset, I will sometimes
> ramble as far as 10 or 15 feet from the computer. It helps if I make the font
> larger so I can glance over and see what kind of errors I've gotten.
> 
> I really love a Bluetooth headset with speech recognition. It's so liberating.
> 
> Your question about foot pedals makes me think of alternative. would it make
> sense to have a handheld keyboard which would be used for command-and-control
> functionality or as an adjunct to speech recognition use? It would have to be
> designed in such a way that it doesn't aggravate a hand injury which may not be
> possible. Anyway, just thinking out loud.
> 
You can get giant piano keyboards that you step on, so how about a giant
computer keyboard? "I wrote 5 miles of code before lunch!" :-)


From pdmef at gmx.net  Fri Jul  3 10:54:26 2009
From: pdmef at gmx.net (Rocco Rutte)
Date: Fri, 3 Jul 2009 16:54:26 +0200
Subject: Custom CFLAGS with distutils
Message-ID: <20090703145426.GJ316@andreas.daprodeges.fqdn.th-h.de>

Hi,

I've been trying to make distutils build mercurial with custom cflags.
The only way this works is to change Makefile because I don't want to
put my changed CFLAGS into the environment and I tend to forget to run
"make" with a CFLAGS=... option.

Google brings up a special "Setup" file which should solve my problem,
but it somehow doesn't. I've tried:

    mercurial mercurial/base85.c -Xcompiler -arch x86_64
    mercurial.base85 mercurial/base85.c -Xcompiler -arch x86_64

for base85.c in the mercurial/ subdirectory. Hacking Makefile does the
trick, but having a Setup file working would never produce merge
conflicts.

What am I doing wrong?

Rocco


From metolone+gmane at gmail.com  Fri Jul  3 10:58:35 2009
From: metolone+gmane at gmail.com (Mark Tolonen)
Date: Fri, 3 Jul 2009 07:58:35 -0700
Subject: =?utf-8?Q?Re:_getting_rid_of_=E2=80=94?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com>
Message-ID: <h2l6aq$t01$1@ger.gmane.org>


"Tep" <petshmidt at googlemail.com> wrote in message 
news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
> On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> > On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
[snip]
> > > > > > how can I replace '?' sign from string? Or do split at that 
> > > > > > character?
> > > > > > Getting unicode error if I try to do it:
> >
> > > > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in 
> > > > > > position
> > > > > > 1: ordinal not in range(128)
> >
> > > > > > Thanks, Pet
> >
> > > > > > script is # -*- coding: UTF-8 -*-
[snip]
> > I just tried a bit of your code above in my interpreter here and it
> > worked fine:
> >
> > |>>> data = 'foo ? bar'
> > |>>> data.split('?')
> > |['foo ', ' bar']
> > |>>> data = u'foo ? bar'
> |>>> data.split(u'?')
> > |[u'foo ', u' bar']
> >
> > Figure out the smallest piece of "html source code" that causes the
> > problem and include that with your next post.
>
> The problem was, I've converted "html source code" to unicode object
> and didn't encoded to utf-8 back, before using split...
> Thanks for help and sorry for not so smart question
> Pet

You'd still benefit from posting some code.  You shouldn't be converting 
back to utf-8 to do a split, you should be using a Unicode string with split 
on the Unicode version of the "html source code".  Also make sure your file 
is actually saved in the encoding you declare.  I print the encoding of your 
symbol in two encodings to illustrate why I suspect this.

Below, assume "data" is your "html source code" as a Unicode string:

# -*- coding: UTF-8 -*-
data = u'foo ? bar'
print repr(u'?'.encode('utf-8'))
print repr(u'?'.encode('windows-1252'))
print data.split(u'?')
print data.split('?')


OUTPUT:

'\xe2\x80\x94'
'\x97'
[u'foo ', u' bar']
Traceback (most recent call last):
  File 
"C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", 
line 427, in ImportFile
    exec codeObj in __main__.__dict__
  File "<auto import>", line 1, in <module>
  File "x.py", line 6, in <module>
    print data.split('?')
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0: 
ordinal not in range(128)

Note that using the Unicode string in split() works.  Also note the decode 
byte in the error message when using a non-Unicode string to split the 
Unicode data.  In your original error message the decode byte that caused an 
error was 0x97, which is 'EM DASH' in Windows-1252 encoding.  Make sure to 
save your source code in the encoding you declare.  If I save the above 
script in windows-1252 encoding and change the coding line to windows-1252 I 
get the same results, but the decode byte is 0x97.

# coding: windows-1252
data = u'foo ? bar'
print repr(u'?'.encode('utf-8'))
print repr(u'?'.encode('windows-1252'))
print data.split(u'?')
print data.split('?')

'\xe2\x80\x94'
'\x97'
[u'foo ', u' bar']
Traceback (most recent call last):
  File 
"C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", 
line 427, in ImportFile
    exec codeObj in __main__.__dict__
  File "<auto import>", line 1, in <module>
  File "x.py", line 6, in <module>
    print data.split('?)
UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0: 
ordinal not in range(128)

-Mark




From nhuthuy.huynh at gmail.com  Fri Jul  3 11:18:58 2009
From: nhuthuy.huynh at gmail.com (Huynh Nhu Thuy)
Date: Fri, 3 Jul 2009 08:18:58 -0700 (PDT)
Subject: Video shows vigorous Jackson before death???
Message-ID: <333e0920-4dd9-4ab3-8e92-8dcfb207fc65@x5g2000prf.googlegroups.com>

Video shows vigorous Jackson before death???

http://hd-family.blogspot.com/2009/07/video-shows-vigorous-jackson-before.html


LOS ANGELES (AFP) ? A video released Thursday showed Michael Jackson
vigorously practicing a song-and-dance routine days before his death,
supporting accounts he had been in good health.

In footage obtained by AFP, the pop legend performed at the Staples
Center in Los Angeles on June 23, two days before he died, as he
prepared for a 50-date set in London starting in July.


http://hd-family.blogspot.com/2009/07/video-shows-vigorous-jackson-before.html


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 11:19:34 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 17:19:34 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <4a4e216e$0$7801$426a74cc@news.free.fr>

kj a ?crit :
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.  I'd love your opinion about
> it.

(snip - others already commented on this code)

> Here's the rub: the code above is more general (hence more reusable)
> by virtue of this trick with the sense parameter, but it is also
> a bit harder to understand.

Perhaps better naming (s/sense/direction/g ?) and a small comment could 
help ?

> This not an unusual situation.  I find that the processing of
> abstracting out common logic often results in code that is harder
> to read, at least for the uninitiated...

IOW : the notion of "clarity" depends on the context (including the 
reader). Anyway, there are algorithms (or implementations of...) that 
are definitly and inherently on the 'hard to read' side - well, 
complexity is something you have to learn to live with, period. The key 
is to try and make it as simple and readable *as possible*.

Also, factoring out common code - or even slightly complex code - often 
makes _client_ code (much) more readable.



From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 11:22:40 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 17:22:40 +0200
Subject: Why re.match()?
In-Reply-To: <h2i54b$eg3$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
Message-ID: <4a4e2227$0$7801$426a74cc@news.free.fr>

kj a ?crit :
(snipo
> To have a special-case
> re.match() method in addition to a general re.search() method is
> antithetical to language minimalism,

FWIW, Python has no pretention to minimalism.


From Scott.Daniels at Acm.Org  Fri Jul  3 11:43:47 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 03 Jul 2009 08:43:47 -0700
Subject: Direct interaction with subprocess - the curse of blocking I/O
In-Reply-To: <58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com>
References: <mailman.2320.1246302955.8015.python-list@python.org>
	<e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com>
	<58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com>
Message-ID: <Z-6dnZ8p8IgUuNPXnZ2dnUVZ_t-dnZ2d@pdx.net>

yam850 wrote:
> I made a python method/function for non blocking read from a file
> object....   I am happy to see comments.

OK, here's a fairly careful set of comments with a few caveats:
Does this work on windows?  The top comment should say where you
know it works.  Does this code correctly read a single line?
perhaps you need to check for a final '\n' whenever you actually
get characters, and break out there.  The rest below simply is
style-changing suggestions; take what you like and leave the rest.

> 
> def non_blocking_readline(f_read=sys.stdin, timeout_select=0.0):
>     """to readline non blocking from the file object 'f_read'
>        for 'timeout_select' see module 'select'"""
>     import select
Typically put imports at the top of the source
XXX   text_lines = ''   # empty string
Either no comment here or say _why_ it is empty.
(A)   text_lines = []  # for result accumulation
if collecting pieces (see below)
(B)   text_lines = ''  # for result accumulation
if collecting a single string

>     while True:       # as long as there are bytes to read
>         try:                              # try select
>             rlist, wlist, xlist = select.select([f_read],                                     [], [],
>                                                timeout_select)
XXX       except:                           # select ERROR
XXX           print >>sys.stderr, ("non_blocking_read select ERROR")
I'd not hide the details of the exception like that.  Don't do empty
excepts. Either don't catch it at all here, (I prefer that) or do
something like the following to capture the error:
           except Exception, why:
               print >>sys.stderr, "non_blocking_read select: %s" % why
>             break
XXX       if DEBUG: print("rlist=%s, wlist=%s, xlist=%s" % (repr(rlist),
XXX  repr(wlist), repr(xlist)))
Don't be scared of vertical space; if you must, define a function DPRINT
to ignore args; use %r to get repr
So, either:
           if DEBUG:
               print("rlist=%r, wlist=%r, xlist=%r" % (
                       rlist, wlist, xlist))
or:
elsewhere:
     def DPRINT(format_str, *args, **kwargs):
         '''Conditionally print formatted output based on DEBUG'''
         if DEBUG:
             print(format_str % (args or kwargs))
and then here:
           DPRINT("rlist=%r, wlist=%r, xlist=%r", rlist, wlist, xlist)

XXX       if  len(rlist) > 0:
Idiomatic Python: use the fact that empty containers evaluate false:
           if  rlist:
>             text_read = f_read.readline() # get a line
XXX            if DEBUG: print("after read/readline text_read:'%s', len=
> %s" % (text_read, repr(len(text_read))))
Similar comment to above:
                if DEBUG:
                    print("after read/readline text_read:%r, len=%s" % (
                                       text_read, len(text_read))
or:
                DPRINT("after read/readline text_read:%r, len=%s",
                       text_read, len(text_read))

XXX           if  len(text_read) > 0:       # there were some bytes
               if text_read:       # there were some bytes
XXX               text_lines = "".join([text_lines, text_read])
Note the join is a good idea only if you have several elements.
For a single concatenation, "=" is just fine.  The (A) case combines
at the end, the (B) case if you expect multiple concatenates are rare.
(A)               text_lines.append(text_read)
(B)               text_lines += text_read

XXX               if DEBUG: print("text_lines:'%s'" % (text_lines))
Similar to above
                if DEBUG:
                    print("text_lines:%r" % text_lines)
or:
                DPRINT("text_lines:%r", text_lines)

XXX           else:
XXX               break       # there was no byte in a line
XXX       else:
XXX           break           # there was no byte in the f_read
To make the flow of control above more clear (one case continues, others
get out), I'd also replace the above with:
                   continue # In one case we keep going
           break  # No new chars found, let's get out.

XXX   if  text_lines  ==  '':
XXX       return None
XXX   else:
XXX       return text_lines
Simplify using 'or's semantics:
(A)   return ''.join(text_lines) or None
(B)   return text_lines or None


So, with everything applied:

     import select

     def DPRINT(format_str, *args, **kwargs):
         '''Conditionally print formatted output based on DEBUG'''
         if DEBUG:
             print(format_str % (args or kwargs))

     def non_blocking_readline(f_read=sys.stdin, timeout_select=0.0):
         """to readline non blocking from the file object 'f_read'

         for 'timeout_select' see module 'select'
         """
         text_lines = ''  # for result accumulation
         while True: # as long as there are bytes to read
             rlist, wlist, xlist = select.select([f_read],   [], [], 

                                                 timeout_select)
             DPRINT("rlist=%r, wlist=%r, xlist=%r",
                       rlist, wlist, xlist)
             if rlist:
                 text_read = f_read.readline() # get a line
                 DPRINT("after read/readline text_read:%r, len=%s",
                           text_read, len(text_read))
                 if text_read:       # there were some bytes
                     text_lines += text_read
                     DPRINT("text_lines:%r", text_lines)
                     continue # Got some chars, keep going.
             break  # Nothing new found, let's get out.
        return text_lines or None


--Scott David Daniels
Scott.Daniels at Acm.Org


From jeanmichel at sequans.com  Fri Jul  3 11:58:48 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 03 Jul 2009 17:58:48 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <4A4E2AB8.6060808@sequans.com>

kj wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.  I'd love your opinion about
> it.
>   
[...]
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
My suggestion on how to improve this part for python novices:
# assuming func is monotonous
if func(high) > func(low):
    direction = 1 # aka sign of the func derivative
elif func(low) > func(high):
    direction = -1
else:
    return None

Avoid using cmp, this will prevent the "what the hell is cmp doing ?" , 
unless you want to teach your students  how to search for inline python 
documentation.
Some other list members have suggested to improve the variable naming. I 
couldn't agree more, in your case, I think clarity can be achieved as 
well with the abstraction (these notions does not necessarily collide).

Here's a link on my how-to-name bible :
http://tottinge.blogsome.com/meaningfulnames/

Jean-Michel



From kurt.alfred.mueller at gmail.com  Fri Jul  3 11:59:24 2009
From: kurt.alfred.mueller at gmail.com (yam850)
Date: Fri, 3 Jul 2009 08:59:24 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org> 
	<e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com> 
	<58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com> 
	<Z-6dnZ8p8IgUuNPXnZ2dnUVZ_t-dnZ2d@pdx.net>
Message-ID: <8a974010-e0c8-470d-b6a8-9934cf61a377@18g2000yqa.googlegroups.com>

On 3 Jul., 17:43, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> yam850 wrote:
> > I made a python method/function for nonblockingread from a file
> > object....   I am happy to see comments.
> OK, here's a fairly careful set of comments with a few caveats:
[snip] valuable comments
> --Scott David Daniels
> Scott.Dani... at Acm.Org


Wow, thats a GREAT answer!!!
Thanks!!!
I will learn a lot while "digesting" this mail.


G
--
yam850


From lie.1296 at gmail.com  Fri Jul  3 12:10:42 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 16:10:42 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <64q3m.2408$ze1.1228@news-server.bigpond.net.au>

kj wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.  I'd love your opinion about
> it.

Sometimes when the decision between clarity and generality becomes too
hard; you might fare better to save the code, go out for a walk to
forget the code, and start a blank text editor. Being in a fresh mind,
you may found an alternative approach, e.g.:

from __future__ import division
def binary_search(lo, hi, func, target, epsilon):
    # reverses hi and lo if monotonically decreasing
    lo, hi = (lo, hi) if func(hi) > func(lo) else (hi, lo)

    param = (lo + hi) / 2

    # loop while not precise enough
    while abs(func(param) - target) > epsilon:
        param = (lo + hi) / 2

        if target < func(param):
            hi = param
        else:
            lo = param
    return param

> The context is the concept of a binary search.  In one of their
> homeworks, my students will have two occasions to use a binary
> search.  This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.
> 
> This seemed straightforward enough, until I realized that, to be
> useful to my students in their homework, this _binary_search function
> had to handle the case in which the passed function was monotonically
> decreasing in the specified interval...
> 
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
> 
> def _binary_search(lo, hi, func, target, epsilon):
>     assert lo < hi
>     assert epsilon > 0
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
>     target_plus = sense * target + epsilon
>     target_minus = sense * target - epsilon
>     while True:
>         param = (lo + hi) * 0.5
>         value = sense * func(param)
>         if value > target_plus:
>             hi = param
>         elif value < target_minus:
>             lo = param
>         else:
>             return param
> 
> 	if lo == hi:
> 	    return None
> 
> My question is: is the business with sense and cmp too "clever"?
> 
> Here's the rub: the code above is more general (hence more reusable)
> by virtue of this trick with the sense parameter, but it is also
> a bit harder to understand.
> 
> This not an unusual situation.  I find that the processing of
> abstracting out common logic often results in code that is harder
> to read, at least for the uninitiated...
> 
> I'd love to know your opinions on this.
> 
> TIA!
> 
> kj
> 


From no.email at please.post  Fri Jul  3 12:19:22 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 16:19:22 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
Message-ID: <h2lb2a$9pt$1@reader1.panix.com>

In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:

>1. Don't use assertions to test argument values!

Out of curiosity, where does this come from? 

Thanks,

kj


From no.email at please.post  Fri Jul  3 12:20:33 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 16:20:33 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2l51m$jps$1@panix3.panix.com>
Message-ID: <h2lb4h$9pt$2@reader1.panix.com>

In <h2l51m$jps$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>First of all, cmp() is gone in Python 3, unfortunately, so I'd avoid
>using it.

Good to know.

>Second, assuming I understand your code correctly, I'd change
>"sense" to "direction" or "order".

Thanks,

kj



From petshmidt at googlemail.com  Fri Jul  3 12:24:43 2009
From: petshmidt at googlemail.com (Tep)
Date: Fri, 3 Jul 2009 09:24:43 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com> 
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com> 
	<mailman.2566.1246633128.8015.python-list@python.org>
Message-ID: <9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>

On 3 Jul., 16:58, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
> "Tep" <petshm... at googlemail.com> wrote in message
>
> news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
>
>
>
>
>
> > On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> > > On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
> [snip]
> > > > > > > how can I replace '?' sign from string? Or do split at that
> > > > > > > character?
> > > > > > > Getting unicode error if I try to do it:
>
> > > > > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in
> > > > > > > position
> > > > > > > 1: ordinal not in range(128)
>
> > > > > > > Thanks, Pet
>
> > > > > > > script is # -*- coding: UTF-8 -*-
> [snip]
> > > I just tried a bit of your code above in my interpreter here and it
> > > worked fine:
>
> > > |>>> data = 'foo ? bar'
> > > |>>> data.split('?')
> > > |['foo ', ' bar']
> > > |>>> data = u'foo ? bar'
> > |>>> data.split(u'?')
> > > |[u'foo ', u' bar']
>
> > > Figure out the smallest piece of "html source code" that causes the
> > > problem and include that with your next post.
>
> > The problem was, I've converted "html source code" to unicode object
> > and didn't encoded to utf-8 back, before using split...
> > Thanks for help and sorry for not so smart question
> > Pet
>
> You'd still benefit from posting some code. ?You shouldn't be converting

I've posted code below

> back to utf-8 to do a split, you should be using a Unicode string with split
> on the Unicode version of the "html source code". ?Also make sure your file
> is actually saved in the encoding you declare. ?I print the encoding of your
> symbol in two encodings to illustrate why I suspect this.

File was indeed in windows-1252, I've changed this. For errors see
below

>
> Below, assume "data" is your "html source code" as a Unicode string:
>
> # -*- coding: UTF-8 -*-
> data = u'foo ? bar'
> print repr(u'?'.encode('utf-8'))
> print repr(u'?'.encode('windows-1252'))
> print data.split(u'?')
> print data.split('?')
>
> OUTPUT:
>
> '\xe2\x80\x94'
> '\x97'
> [u'foo ', u' bar']
> Traceback (most recent call last):
> ? File
> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> line 427, in ImportFile
> ? ? exec codeObj in __main__.__dict__
> ? File "<auto import>", line 1, in <module>
> ? File "x.py", line 6, in <module>
> ? ? print data.split('?')
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
> ordinal not in range(128)
>
> Note that using the Unicode string in split() works. ?Also note the decode
> byte in the error message when using a non-Unicode string to split the
> Unicode data. ?In your original error message the decode byte that caused an
> error was 0x97, which is 'EM DASH' in Windows-1252 encoding. ?Make sure to
> save your source code in the encoding you declare. ?If I save the above
> script in windows-1252 encoding and change the coding line to windows-1252 I
> get the same results, but the decode byte is 0x97.
>
> # coding: windows-1252
> data = u'foo ? bar'
> print repr(u'?'.encode('utf-8'))
> print repr(u'?'.encode('windows-1252'))
> print data.split(u'?')
> print data.split('?')
>
> '\xe2\x80\x94'
> '\x97'
> [u'foo ', u' bar']
> Traceback (most recent call last):
> ? File
> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> line 427, in ImportFile
> ? ? exec codeObj in __main__.__dict__
> ? File "<auto import>", line 1, in <module>
> ? File "x.py", line 6, in <module>
> ? ? print data.split('?)
> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0:
> ordinal not in range(128)
>
> -Mark

#! /usr/bin/python
# -*- coding: UTF-8 -*-
import urllib2
import re
def getTitle(input):
    title = re.search('<title>(.*?)</title>', input)
    title = title.group(1)
    print "FULL TITLE", title.encode('UTF-8')
    parts = title.split(' ? ')
    return parts[0]


def getWebPage(url):
    user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
    headers = { 'User-Agent' : user_agent }
    req = urllib2.Request(url, '', headers)
    response = urllib2.urlopen(req)
    the_page = unicode(response.read(), 'UTF-8')
    return the_page


def main():
    url = "http://bg.wikipedia.org/wiki/
%D0%91%D0%B0%D1%85%D1%80%D0%B5%D0%B9%D0%BD"
    title = getTitle(getWebPage(url))
    print title[0]


if __name__ == "__main__":
    main()


Traceback (most recent call last):
  File "C:\user\Projects\test\src\new_main.py", line 29, in <module>
    main()
  File "C:\user\Projects\test\src\new_main.py", line 24, in main
    title = getTitle(getWebPage(url))
FULL TITLE ?????????????? ??? ??????????????????
  File "C:\user\Projects\test\src\new_main.py", line 9, in getTitle
    parts = title.split(' ??? ')
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position
1: ordinal not in range(128)


From keflavich at gmail.com  Fri Jul  3 12:30:21 2009
From: keflavich at gmail.com (Keflavich)
Date: Fri, 3 Jul 2009 09:30:21 -0700 (PDT)
Subject: Compiling 64 bit python on a mac - cannot compute sizeof (int)
Message-ID: <b118d0f7-c997-4182-b734-8d39d84016d3@g7g2000prg.googlegroups.com>

I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X
10.5.7), and am running into a problem during the configure stage.

I configure with:
./configure --enable-framework=/Library/Frameworks --enable-
universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all -
with-readline-dir=/usr/local

because I want 64 and 32 bit, and I needed to install a 64 bit
readline as a prerequisite.

configure fails at:
checking size of int... configure: error: cannot compute sizeof (int)

I'm not reporting this as a bug because I know it's a problem with my
path somewhere (a friend with an identical computer but slightly
different setup was able to compile without a problem), but I don't
know what paths to change.  Any tips?

Thanks,
Adam


From no.email at please.post  Fri Jul  3 12:30:33 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 16:30:33 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com> <h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
	<h2l1kc$2tj$1@reader1.panix.com> <h2l4o8$sn3$1@panix3.panix.com>
Message-ID: <h2lbn9$9pt$3@reader1.panix.com>

In <h2l4o8$sn3$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>In article <h2l1kc$2tj$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:

>You may find this enlightening:

>http://www.python.org/doc/1.4/lib/node52.html

Indeed.  Thank you.

kj


From http  Fri Jul  3 12:33:35 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 09:33:35 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <7xk52p4tgg.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
>     target_plus = sense * target + epsilon
>     target_minus = sense * target - epsilon
>     ...

The code looks confusing to me and in some sense incorrect.  Suppose
func(hi)==func(lo)==target.  In this case the solver gives up
and returns None even though it already has found a root.

Also, the stuff with the sense parameter, and target_minus and
target_plus looks messy.  I do like to use cmp.  I'd just write
something like (untested):

 def _binary_search(lo, hi, func, target, epsilon):
     y_hi, y_lo = func(hi), func(lo)
     
     while True:
         x_new = (lo + hi) * 0.5
         y_new = func(x_new)
         if abs(y_new - target) < epsilon: 
            return x_new
         elif cmp(y_new, target) == cmp(y_hi, target):
            hi = x_new
         else:
            lo = x_new
         if lo == hi:
            return None 

This uses an extra couple function calls in that trivial case, of
course.


From lie.1296 at gmail.com  Fri Jul  3 12:34:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 16:34:49 GMT
Subject: Why re.match()?
In-Reply-To: <025db0a6$0$20657$c3e8da3@news.astraweb.com>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <Jqq3m.2411$ze1.1142@news-server.bigpond.net.au>

Steven D'Aprano wrote:
> On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:
> 
>> I'm sure that it is possible to find cases in which the *current*
>> implementation of re.search() would be inefficient, but that's because
>> this implementation is perverse, which, I guess, is ultimately the point
>> of my original post.  Why privilege the special case of a
>> start-of-string anchor?  
> 
> Because wanting to see if a string matches from the beginning is a very 
> important and common special case.
> 

I find the most oddest thing about re.match is that it have an implicit
beginning anchor, but not implicit end anchor. I thought it was much
more common to ensure that a string matches a certain pattern, than just
matching the beginning. But everyone's mileages vary.


From buzzard at urubu.freeserve.co.uk  Fri Jul  3 12:35:45 2009
From: buzzard at urubu.freeserve.co.uk (duncan smith)
Date: Fri, 03 Jul 2009 17:35:45 +0100
Subject: Is Psyco good for Python 2.6.1?
In-Reply-To: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
References: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
Message-ID: <h2lc13$1aeh$1@energise.enta.net>

Russ P. wrote:
> I need to speed up some Python code, and I discovered Psyco. However,
> the Psyco web page has not been updated since December 2007. Before I
> go to the trouble of installing it, does anyone know if it is still
> good for Python 2.6.1? Thanks.

If you look at http://psyco.sourceforge.net/ it would seem so (a Windows
binary for 2.6 is available).  You might want to wait a little while
because Psyco 2 is likely to be released very soon (tomorrow, the last I
heard).

Duncan


From hobesh at gmail.com  Fri Jul  3 12:53:19 2009
From: hobesh at gmail.com (Zach Hobesh)
Date: Fri, 3 Jul 2009 09:53:19 -0700
Subject: Config files with different types
In-Reply-To: <c83cde5a0907022355y706ea932w78649a17ed756809@mail.gmail.com>
References: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com> 
	<c83cde5a0907022355y706ea932w78649a17ed756809@mail.gmail.com>
Message-ID: <d4ea8a900907030953x3a8d91d4q505337921d7d9b5e@mail.gmail.com>

yaml looks pretty interesting.  Also, I wouldn't have to change much,
I would still use the same function, and still output a dict.

Thanks!

-Zach

On Thu, Jul 2, 2009 at 11:55 PM, Javier Collado<javier.collado at gmail.com> wrote:
> Hello,
>
> Have you considered using something that is already developed?
>
> You could take a look at this presentation for an overview of what's available:
> http://us.pycon.org/2009/conference/schedule/event/5/
>
> Anyway, let me explain that, since I "discovered" it, my favourite
> format for configuration files is yaml (http://yaml.org/,
> http://pyyaml.org/). It's easy to read, easy to write, available in
> different programming languagues, etc. In addition to this, type
> conversion is already in place so I think it covers your requirement.
> For example:
>
> IIn [1]: import yaml
>
> In [2]: yaml.load("""name: person name
> ? ...: age: 25
> ? ...: is_programmer: true""")
> Out[2]: {'age': 25, 'is_programmer': True, 'name': 'person name'}
>
> Best regards,
> ? ?Javier
>
> 2009/7/2 Zach Hobesh <hobesh at gmail.com>:
>> Hi all,
>>
>> I've written a function that reads a specifically formatted text file
>> and spits out a dictionary. ?Here's an example:
>>
>> config.txt:
>>
>> Destination = C:/Destination
>> Overwrite = True
>>
>>
>> Here's my function that takes 1 argument (text file)
>>
>> the_file = open(textfile,'r')
>> linelist = the_file.read().split('\n')
>> the_file.close()
>> configs = {}
>> for line in linelist:
>> ? ? ? try:
>> ? ? ? ? ? ? ?key,value = line.split('=')
>> ? ? ? ? ? ? ?key.strip()
>> ? ? ? ? ? ? ?value.strip()
>> ? ? ? ? ? ? ?key.lower()
>> ? ? ? ? ? ? ?value.lower()
>> ? ? ? ? ? ? ?configs[key] = value
>>
>> ? ? ? except ValueError:
>> ? ? ? ? ? ? ?break
>>
>> so I call this on my config file, and then I can refer back to any
>> config in my script like this:
>>
>> shutil.move(your_file,configs['destination'])
>>
>> which I like because it's very clear and readable.
>>
>> So this works great for simple text config files. ?Here's how I want
>> to improve it:
>>
>> I want to be able to look at the value and determine what type it
>> SHOULD be. ?Right now, configs['overwrite'] = 'true' (a string) when
>> it might be more useful as a boolean. ?Is there a quick way to do
>> this? ?I'd also like to able to read '1' as an in, '1.0' as a float,
>> etc...
>>
>> I remember once I saw a script that took a string and tried int(),
>> float() wrapped in a try except, but I was wondering if there was a
>> more direct way.
>>
>> Thanks in advance,
>>
>> Zach
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>
>


From python at mrabarnett.plus.com  Fri Jul  3 12:54:10 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 17:54:10 +0100
Subject: getting rid of =?UTF-8?B?4oCU?=
In-Reply-To: <9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com>
	<mailman.2566.1246633128.8015.python-list@python.org>
	<9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>
Message-ID: <4A4E37B2.10300@mrabarnett.plus.com>

Tep wrote:
> On 3 Jul., 16:58, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
>> "Tep" <petshm... at googlemail.com> wrote in message
>>
>> news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
>>
>>
>>
>>
>>
>>> On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
>>>> On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
>> [snip]
>>>>>>>> how can I replace '?' sign from string? Or do split at that
>>>>>>>> character?
>>>>>>>> Getting unicode error if I try to do it:
>>>>>>>> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in
>>>>>>>> position
>>>>>>>> 1: ordinal not in range(128)
>>>>>>>> Thanks, Pet
>>>>>>>> script is # -*- coding: UTF-8 -*-
>> [snip]
>>>> I just tried a bit of your code above in my interpreter here and it
>>>> worked fine:
>>>> |>>> data = 'foo ? bar'
>>>> |>>> data.split('?')
>>>> |['foo ', ' bar']
>>>> |>>> data = u'foo ? bar'
>>> |>>> data.split(u'?')
>>>> |[u'foo ', u' bar']
>>>> Figure out the smallest piece of "html source code" that causes the
>>>> problem and include that with your next post.
>>> The problem was, I've converted "html source code" to unicode object
>>> and didn't encoded to utf-8 back, before using split...
>>> Thanks for help and sorry for not so smart question
>>> Pet
>> You'd still benefit from posting some code.  You shouldn't be converting
> 
> I've posted code below
> 
>> back to utf-8 to do a split, you should be using a Unicode string with split
>> on the Unicode version of the "html source code".  Also make sure your file
>> is actually saved in the encoding you declare.  I print the encoding of your
>> symbol in two encodings to illustrate why I suspect this.
> 
> File was indeed in windows-1252, I've changed this. For errors see
> below
> 
>> Below, assume "data" is your "html source code" as a Unicode string:
>>
>> # -*- coding: UTF-8 -*-
>> data = u'foo ? bar'
>> print repr(u'?'.encode('utf-8'))
>> print repr(u'?'.encode('windows-1252'))
>> print data.split(u'?')
>> print data.split('?')
>>
>> OUTPUT:
>>
>> '\xe2\x80\x94'
>> '\x97'
>> [u'foo ', u' bar']
>> Traceback (most recent call last):
>>   File
>> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
>> line 427, in ImportFile
>>     exec codeObj in __main__.__dict__
>>   File "<auto import>", line 1, in <module>
>>   File "x.py", line 6, in <module>
>>     print data.split('?')
>> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
>> ordinal not in range(128)
>>
>> Note that using the Unicode string in split() works.  Also note the decode
>> byte in the error message when using a non-Unicode string to split the
>> Unicode data.  In your original error message the decode byte that caused an
>> error was 0x97, which is 'EM DASH' in Windows-1252 encoding.  Make sure to
>> save your source code in the encoding you declare.  If I save the above
>> script in windows-1252 encoding and change the coding line to windows-1252 I
>> get the same results, but the decode byte is 0x97.
>>
>> # coding: windows-1252
>> data = u'foo ? bar'
>> print repr(u'?'.encode('utf-8'))
>> print repr(u'?'.encode('windows-1252'))
>> print data.split(u'?')
>> print data.split('?')
>>
>> '\xe2\x80\x94'
>> '\x97'
>> [u'foo ', u' bar']
>> Traceback (most recent call last):
>>   File
>> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
>> line 427, in ImportFile
>>     exec codeObj in __main__.__dict__
>>   File "<auto import>", line 1, in <module>
>>   File "x.py", line 6, in <module>
>>     print data.split('?)
>> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0:
>> ordinal not in range(128)
>>
>> -Mark
> 
> #! /usr/bin/python
> # -*- coding: UTF-8 -*-
> import urllib2
> import re
> def getTitle(input):
>     title = re.search('<title>(.*?)</title>', input)

The input is Unicode, so it's probably better for the regular expression
to also be Unicode:

     title = re.search(u'<title>(.*?)</title>', input)

(In the current implementation it actually doesn't matter.)

>     title = title.group(1)
>     print "FULL TITLE", title.encode('UTF-8')
>     parts = title.split(' ? ')

The title is Unicode, so the string with which you're splitting should
also be Unicode:

     parts = title.split(u' ? ')

>     return parts[0]
> 
> 
> def getWebPage(url):
>     user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
>     headers = { 'User-Agent' : user_agent }
>     req = urllib2.Request(url, '', headers)
>     response = urllib2.urlopen(req)
>     the_page = unicode(response.read(), 'UTF-8')
>     return the_page
> 
> 
> def main():
>     url = "http://bg.wikipedia.org/wiki/
> %D0%91%D0%B0%D1%85%D1%80%D0%B5%D0%B9%D0%BD"
>     title = getTitle(getWebPage(url))
>     print title[0]
> 
> 
> if __name__ == "__main__":
>     main()
> 
> 
> Traceback (most recent call last):
>   File "C:\user\Projects\test\src\new_main.py", line 29, in <module>
>     main()
>   File "C:\user\Projects\test\src\new_main.py", line 24, in main
>     title = getTitle(getWebPage(url))
> FULL TITLE ?????????????? ??? ??????????????????
>   File "C:\user\Projects\test\src\new_main.py", line 9, in getTitle
>     parts = title.split(' ??? ')
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position
> 1: ordinal not in range(128)


From kd at kendyck.com  Fri Jul  3 13:00:31 2009
From: kd at kendyck.com (Ken Dyck)
Date: Fri, 3 Jul 2009 10:00:31 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP: How to define API?
References: <mailman.2520.1246573083.8015.python-list@python.org>
Message-ID: <08bb0349-4bc7-448c-9ae5-49eca6d7f3ae@g7g2000prg.googlegroups.com>

On Jul 2, 6:17?pm, Allen Fowler <allen.fow... at yahoo.com> wrote:
> Since I need to work with other platforms, pickle is out... ?what are the alternatives? ?XML? JSON?

Don't forget YAML (http://yaml.org). Libraries available for Python
and .NET, among others.

-Ken


From schickb at gmail.com  Fri Jul  3 13:03:32 2009
From: schickb at gmail.com (Brad)
Date: Fri, 3 Jul 2009 10:03:32 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>

On Jul 3, 12:57?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> I've never needed such a split function, and I don't like the name, and
> the functionality isn't general enough. I'd prefer something which splits
> the input sequence into as many sublists as necessary, according to the
> output of the key function.

That's not a bad idea, I'll have to experiment with the alternatives.
My thought process for this, however, was that filter itself already
splits the sequence and it would have been more useful had it not
thrown away "half" of what it discovers. It could have been written to
returned two sequences with very litter perf hit for all but very
large input sequences, and been useful in more situations. What I
*really* wanted was a way to make filter itself more useful, since it
seems a bit silly to have two very similar functions.

Maybe this would be difficult to get into the core, but how about this
idea: Rename the current filter function to something like "split" or
"partition" (which I agree may be a better name) and modify it to
return the desired true and false sequences. Then recreate the
existing "filter" function with a wrapper that throws away the false
sequence.

Here are two simplified re-creations of situations where I could have
used partition (aka split):

words = ['this', 'is', 'a', 'bunch', 'of', 'words']
short, long = partition(words, lambda w: len(w) < 3)

d = {1 : 'w', 2 : 'x' ,3 : 'y' ,4 : 'z'}
keys = [1, 3, 4, 9]
found, missing = partition(keys, d.has_key)


There are probably a dozen other approaches, but the existing "filter"
is fast, clear, and *almost* good enough. So when is this useful in
general: Whenever filter itself is useful, but you want to use both
sides of the partitioning work it already does.


-Brad


From http  Fri Jul  3 13:14:00 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 10:14:00 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
Message-ID: <7xr5wx8zaf.fsf@ruckus.brouhaha.com>

Brad <schickb at gmail.com> writes:
> Maybe this would be difficult to get into the core, but how about this
> idea: Rename the current filter function to something like "split" or
> "partition" (which I agree may be a better name) and modify it to
> return the desired true and false sequences. Then recreate the
> existing "filter" function with a wrapper that throws away the false
> sequence.

This isn't so attractive, since filter takes a sequence input but
returns a list.  So if I have an iterator that produces a billion
elements of which I expect three to satisfy some predicate, then
   xs = filter(func, seq)
as currently implemented will build a 3-element list and return it.  
Under your suggestion, it would also build and throw away an (almost)
billion element list.


From lie.1296 at gmail.com  Fri Jul  3 13:27:59 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 17:27:59 GMT
Subject: Sequence splitting
In-Reply-To: <e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
Message-ID: <zcr3m.2414$ze1.1263@news-server.bigpond.net.au>

Brad wrote:
> On Jul 3, 12:57 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>> I've never needed such a split function, and I don't like the name, and
>> the functionality isn't general enough. I'd prefer something which splits
>> the input sequence into as many sublists as necessary, according to the
>> output of the key function.
> 
> That's not a bad idea, I'll have to experiment with the alternatives.
> My thought process for this, however, was that filter itself already
> splits the sequence and it would have been more useful had it not
> thrown away "half" of what it discovers. It could have been written to
> returned two sequences with very litter perf hit for all but very
> large input sequences, and been useful in more situations. What I
> *really* wanted was a way to make filter itself more useful, since it
> seems a bit silly to have two very similar functions.

It's not that easy. filter is nearly by definition a lazy function. The
various split/group functions is impossible to be made an efficient
iterator, since they must traverse the whole list before being sure that
they have finished the group/part of the split (or even to be sure that
they have all the group keys).

> Maybe this would be difficult to get into the core, but how about this
> idea: Rename the current filter function to something like "split" or
> "partition" (which I agree may be a better name) and modify it to
> return the desired true and false sequences. Then recreate the
> existing "filter" function with a wrapper that throws away the false
> sequence.

filter has a very deep root in functional programming, I doubt it will
change any time soon. Also, consider infinite iterators. With the
"filter as wrapper to partition" scheme, it is impossible for
split/group/partition to use infinite iterator.


From fiafulli at hotmail.it  Fri Jul  3 13:39:27 2009
From: fiafulli at hotmail.it (fiafulli)
Date: Fri, 3 Jul 2009 19:39:27 +0200
Subject: PyGtkSourceView / PyScintilla
Message-ID: <4a4e41d5$0$836$4fafbaef@reader5.news.tin.it>

Hello to all.
I would have need of the recent version (possibly most recent) than one of 
the two controls in subject.
I think that wrapper for scintilla it would be better but creed that the 
development for pygtk is stopped.

therefore I'm more inclined for GtkSourceView (than today it is to the 
version 2.6.0 http://projects.gnome.org/gtksourceview/).

In the specific I need the version for windows (for that for linux I have 
not still tried but I must not have problems) of which a setup exists for 
python 2.5 but it is stop to version 2.2 
http://ftp.gnome.org/pub/gnome/binaries/win32/pygtksourceview/2.2/).

Someone would be to post the compiled in issue (if it were last version 
would be fantastic!)? or to explain step to me step as to compile it to me 
alone on windows (I have tried installing mingw, msys, autoconf, automake, 
libtools, and all the other ones of time in time, I have begun to compile 
but they are stopped to me on reference lacking pygobject 2.15 or something 
of the sort. I lost all morning!)?

The version of python that I use is the 2.5.4. on windows xp sp3 (and ubuntu 
9.04)

Thanks in advance,
Francesco

p.s.: sorry for my bad english 




From user at example.net  Fri Jul  3 13:42:39 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 19:42:39 +0200
Subject: stringio+tarfile
In-Reply-To: <h2ksj9$g38$00$1@news.t-online.com>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<4a4debb1$0$1106$4fafbaef@reader3.news.tin.it>
	<h2ksj9$g38$00$1@news.t-online.com>
Message-ID: <4a4e4311$0$47538$4fafbaef@reader1.news.tin.it>

Peter Otten wrote:

> gettarinfo() expects a real file, not a file-like object.
> You have to create your TarInfo manually.

ok... which attributes are mandatory, and which optional?


> I recommend that you have a look into the tarfile module's source code.
>

i will try... but:


$ cat /usr/lib/python2.3/tarfile.py | wc -l
1938

wow! it'll take some time ;-)


> The following seems to work:
> 
> import sys
> import time
> import tarfile
> import StringIO
> 
> sf1 = "first.txt", StringIO.StringIO("one one\n")
> sf2 = "second.txt", StringIO.StringIO("two\n")
> tf = StringIO.StringIO()
> 
> tar = tarfile.open(fileobj=tf , mode="w")
> 
> mtime = time.time()
> for name, f in [sf1 , sf2]:
>     ti = tarfile.TarInfo(name)
>     ti.size = f.len
>     ti.mtime = mtime
>     # add more attributes as needed 
>     tar.addfile(ti, f)
> 
> sys.stdout.write(tf.getvalue())
> 
> Peter
> 

much obliged mr otten

bye


From sajmikins at gmail.com  Fri Jul  3 13:44:52 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 10:44:52 -0700 (PDT)
Subject: PSP Caching
References: <mailman.2548.1246612730.8015.python-list@python.org>
Message-ID: <3e1c0979-fb6b-4d6e-80e5-a4af8d5fd96a@a36g2000yqc.googlegroups.com>

On Jul 3, 5:18?am, Johnson Mpeirwe <mjohn... at cfi.co.ug> wrote:
> Hello All,
>
> How do I stop caching of Python Server Pages (or whatever causes changes
> in a page not to be noticed in a web browser)? I am new to developing
> web applications in Python and after looking at implementations of PSP
> like Spyce (which I believed introduces new unnecessary non-PSP syntax),
> I decided to write my own PSP applications from scratch. When I modify a
> file, I keep getting the old results until I intentionally introduce an
> error (e.g parse error) and correct it after to have the changes
> noticed. There's no proxy (I am working on a windows machine unplugged
> from the network). I have Googled and no documents seem to talk about
> this. Is there any particular mod_python directive I must set in my
> Apache configuration to fix this?
>
> Any help will be highly appreciated.
>
> Johnson

I don't know much about caching with apache, but the answer mght be on
this page: http://httpd.apache.org/docs/2.2/caching.html

Meanwhile, couldn't you just send apache a restart signal when you
modify your code?

HTH,
~Simon


From Scott.Daniels at Acm.Org  Fri Jul  3 13:47:15 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 03 Jul 2009 10:47:15 -0700
Subject: Sequence splitting
In-Reply-To: <025dab69$0$20657$c3e8da3@news.astraweb.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <yM2dnX69Jo7k39PXnZ2dnUVZ_hCdnZ2d@pdx.net>

Steven D'Aprano wrote:
> I've never needed such a split function, and I don't like the name, and 
> the functionality isn't general enough. I'd prefer something which splits 
> the input sequence into as many sublists as necessary, according to the 
> output of the key function. Something like itertools.groupby(), except it 
> runs through the entire sequence and collates all the elements with 
> identical keys.
> 
> splitby(range(10), lambda n: n%3)
> => [ (0, [0, 3, 6, 9]),
>      (1, [1, 4, 7]), 
>      (2, [2, 5, 8]) ]
> 
> Your split() would be nearly equivalent to this with a key function that 
> returns a Boolean.

Well, here is my go at doing the original with iterators:

def splitter(source, test=bool):
     a, b = itertools.tee((x, test(x)) for x in source)
     return (data for data, decision in a if decision), (
	    data for data, decision in b if not decision)

This has the advantage that it can operate on infinite lists.  For
something like splitby for grouping, I seem to need to know the cases
up front:

def _make_gen(particular, src):
      return (x for x, c in src if c == particular)

def splitby(source, cases, case):
     '''Produce a dict of generators for case(el) for el in source'''
     decided = itertools.tee(((x, case(x)) for x in source), len(cases))
     return dict((c, _make_gen(c, src))
                 for c, src in zip(cases, decided))

example:

def classify(n):
     '''Least prime factor of a few'''
     for prime in [2, 3, 5, 7]:
         if n % prime == 0:
             return prime
     return 0

for k,g in splitby(range(50), (2, 3, 5, 7, 0), classify).items():
     print('%s: %s' % (k, list(g)))

0: [1, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47]
2: [0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24,
     26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48]
3: [3, 9, 15, 21, 27, 33, 39, 45]
5: [5, 25, 35]
7: [7, 49]

--Scott David Daniels
Scott.Daniels at Acm.Org


From alan.isaac at gmail.com  Fri Jul  3 13:50:23 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 17:50:23 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2lb2a$9pt$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
Message-ID: <zxr3m.613$P5.65@nwrddc02.gnilink.net>

> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:
>> 1. Don't use assertions to test argument values!


On 7/3/2009 12:19 PM kj apparently wrote:
> Out of curiosity, where does this come from? 


http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_stmt
"The current code generator emits no code for an assert statement when optimization is requested at compile time."

Alan Isaac


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 14:03:07 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 18:03:07 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
Message-ID: <025e3974$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 16:19:22 +0000, kj wrote:

> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac
> <alan.isaac at gmail.com> writes:
> 
>>1. Don't use assertions to test argument values!
> 
> Out of curiosity, where does this come from?

Assertions are disabled when you run Python with the -O (optimise) flag. 
If you rely on assertions to verify data, then any time the user runs 
python with -O your code will be running without error checking.

assert should be used to verify program logic, not to sanitize data.


-- 
Steven


From kee at kagi.com  Fri Jul  3 14:08:19 2009
From: kee at kagi.com (Kee Nethery)
Date: Fri, 3 Jul 2009 11:08:19 -0700
Subject: Python debugger
In-Reply-To: <740981.83964.qm@web7901.mail.in.yahoo.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
Message-ID: <4A19FA5C-C135-480F-BFD1-82B7AF1500A8@kagi.com>

It's not free but I like the debugger in Komodo IDE.
Lets me simulate a web connection, lets me step through the code and  
examine the variables as it executes, can be run remotely (have not  
played with that aspect yet).
Does variable inspection of the variables so you can dive into the  
parts of arrays and dictionaries to see what the (for example) 5th  
item of the 4th item named "blah" is set to and what type of data  
element it is (int, unicode, etc). I find it tremendously useful as a  
newbie to Python.
Kee Nethery


From patrick.just4fun at gmail.com  Fri Jul  3 14:18:51 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Fri, 03 Jul 2009 20:18:51 +0200
Subject: Reversible Debugging
Message-ID: <4A4E4B8B.7090104@gmail.com>

Hello,

I am interested if there are any python modules, that supports 
reversible debugging aka stepping backwards. Any links or ideas would be 
helpful, because I am thinking of implementing something like that.

Thanks in advance,
Patrick


From petshmidt at googlemail.com  Fri Jul  3 14:34:21 2009
From: petshmidt at googlemail.com (Tep)
Date: Fri, 3 Jul 2009 11:34:21 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com> 
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com> 
	<mailman.2566.1246633128.8015.python-list@python.org>
	<9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>
	<mailman.2569.1246640050.8015.python-list@python.org>
Message-ID: <a2f5ccb7-bdb8-414d-94a0-f6eb36a328fc@26g2000yqk.googlegroups.com>

On 3 Jul., 18:54, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Tep wrote:
> > On 3 Jul., 16:58, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
> >> "Tep" <petshm... at googlemail.com> wrote in message
>
> >>news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
>
> >>> On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> >>>> On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
> >> [snip]
> >>>>>>>> how can I replace '?' sign from string? Or do split at that
> >>>>>>>> character?
> >>>>>>>> Getting unicode error if I try to do it:
> >>>>>>>> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in
> >>>>>>>> position
> >>>>>>>> 1: ordinal not in range(128)
> >>>>>>>> Thanks, Pet
> >>>>>>>> script is # -*- coding: UTF-8 -*-
> >> [snip]
> >>>> I just tried a bit of your code above in my interpreter here and it
> >>>> worked fine:
> >>>> |>>> data = 'foo ? bar'
> >>>> |>>> data.split('?')
> >>>> |['foo ', ' bar']
> >>>> |>>> data = u'foo ? bar'
> >>> |>>> data.split(u'?')
> >>>> |[u'foo ', u' bar']
> >>>> Figure out the smallest piece of "html source code" that causes the
> >>>> problem and include that with your next post.
> >>> The problem was, I've converted "html source code" to unicode object
> >>> and didn't encoded to utf-8 back, before using split...
> >>> Thanks for help and sorry for not so smart question
> >>> Pet
> >> You'd still benefit from posting some code. ?You shouldn't be converting
>
> > I've posted code below
>
> >> back to utf-8 to do a split, you should be using a Unicode string with split
> >> on the Unicode version of the "html source code". ?Also make sure your file
> >> is actually saved in the encoding you declare. ?I print the encoding of your
> >> symbol in two encodings to illustrate why I suspect this.
>
> > File was indeed in windows-1252, I've changed this. For errors see
> > below
>
> >> Below, assume "data" is your "html source code" as a Unicode string:
>
> >> # -*- coding: UTF-8 -*-
> >> data = u'foo ? bar'
> >> print repr(u'?'.encode('utf-8'))
> >> print repr(u'?'.encode('windows-1252'))
> >> print data.split(u'?')
> >> print data.split('?')
>
> >> OUTPUT:
>
> >> '\xe2\x80\x94'
> >> '\x97'
> >> [u'foo ', u' bar']
> >> Traceback (most recent call last):
> >> ? File
> >> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> >> line 427, in ImportFile
> >> ? ? exec codeObj in __main__.__dict__
> >> ? File "<auto import>", line 1, in <module>
> >> ? File "x.py", line 6, in <module>
> >> ? ? print data.split('?')
> >> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
> >> ordinal not in range(128)
>
> >> Note that using the Unicode string in split() works. ?Also note the decode
> >> byte in the error message when using a non-Unicode string to split the
> >> Unicode data. ?In your original error message the decode byte that caused an
> >> error was 0x97, which is 'EM DASH' in Windows-1252 encoding. ?Make sure to
> >> save your source code in the encoding you declare. ?If I save the above
> >> script in windows-1252 encoding and change the coding line to windows-1252 I
> >> get the same results, but the decode byte is 0x97.
>
> >> # coding: windows-1252
> >> data = u'foo ? bar'
> >> print repr(u'?'.encode('utf-8'))
> >> print repr(u'?'.encode('windows-1252'))
> >> print data.split(u'?')
> >> print data.split('?')
>
> >> '\xe2\x80\x94'
> >> '\x97'
> >> [u'foo ', u' bar']
> >> Traceback (most recent call last):
> >> ? File
> >> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> >> line 427, in ImportFile
> >> ? ? exec codeObj in __main__.__dict__
> >> ? File "<auto import>", line 1, in <module>
> >> ? File "x.py", line 6, in <module>
> >> ? ? print data.split('?)
> >> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0:
> >> ordinal not in range(128)
>
> >> -Mark
>
> > #! /usr/bin/python
> > # -*- coding: UTF-8 -*-
> > import urllib2
> > import re
> > def getTitle(input):
> > ? ? title = re.search('<title>(.*?)</title>', input)
>
> The input is Unicode, so it's probably better for the regular expression
> to also be Unicode:
>
> ? ? ?title = re.search(u'<title>(.*?)</title>', input)
>
> (In the current implementation it actually doesn't matter.)
>
> > ? ? title = title.group(1)
> > ? ? print "FULL TITLE", title.encode('UTF-8')
> > ? ? parts = title.split(' ? ')
>
> The title is Unicode, so the string with which you're splitting should
> also be Unicode:
>
> ? ? ?parts = title.split(u' ? ')
>


Oh, so simple. I'm new to python and still feel uncomfortable with
unicode stuff.

Thanks to all for help!

>
>
> > ? ? return parts[0]
>
> > def getWebPage(url):
> > ? ? user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
> > ? ? headers = { 'User-Agent' : user_agent }
> > ? ? req = urllib2.Request(url, '', headers)
> > ? ? response = urllib2.urlopen(req)
> > ? ? the_page = unicode(response.read(), 'UTF-8')
> > ? ? return the_page
>
> > def main():
> > ? ? url = "http://bg.wikipedia.org/wiki/
> > %D0%91%D0%B0%D1%85%D1%80%D0%B5%D0%B9%D0%BD"
> > ? ? title = getTitle(getWebPage(url))
> > ? ? print title[0]
>
> > if __name__ == "__main__":
> > ? ? main()
>
> > Traceback (most recent call last):
> > ? File "C:\user\Projects\test\src\new_main.py", line 29, in <module>
> > ? ? main()
> > ? File "C:\user\Projects\test\src\new_main.py", line 24, in main
> > ? ? title = getTitle(getWebPage(url))
> > FULL TITLE ?????????????? ??? ?????????????????
> > ? File "C:\user\Projects\test\src\new_main.py", line 9, in getTitle
> > ? ? parts = title.split(' ??? ')
> > UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position
> > 1: ordinal not in range(128)



From charles at declareSub.com  Fri Jul  3 14:50:48 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Fri, 3 Jul 2009 14:50:48 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <025e3974$0$20657$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<025e3974$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <50230590-3F00-45ED-A1B2-DCA85366C416@declareSub.com>


On Jul 3, 2009, at 2:03 PM, Steven D'Aprano wrote:

> On Fri, 03 Jul 2009 16:19:22 +0000, kj wrote:
>
>> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac
>> <alan.isaac at gmail.com> writes:
>>
>>> 1. Don't use assertions to test argument values!
>>
>> Out of curiosity, where does this come from?
>
> Assertions are disabled when you run Python with the -O (optimise)  
> flag.
> If you rely on assertions to verify data, then any time the user runs
> python with -O your code will be running without error checking.
>
> assert should be used to verify program logic, not to sanitize data.


I wouldn't describe the use of an assert statement in the original  
code as data sanitizing, but rather as a precondition.  And with that  
description, the use of an assert statement that might be compiled  
away is not unreasonable; indeed, it certainly is so in the context of  
design by contract.

Charles Yeomans


From tjreedy at udel.edu  Fri Jul  3 14:57:20 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 14:57:20 -0400
Subject: Python 3.0 (pinin' for the fjords)
In-Reply-To: <Hue3m.534$P5.391@nwrddc02.gnilink.net>
References: <mailman.2526.1246576243.8015.python-list@python.org>
	<Hue3m.534$P5.391@nwrddc02.gnilink.net>
Message-ID: <h2lkah$4b8$1@ger.gmane.org>

Alan G Isaac wrote:
> Using the 3.1 Windows installer, I chose that I did not
> want the extensions registered, and the installer
> unregistered the .py and .pyw extensions (which I had wanted
> to keep associated with Python 2.6).
> 
> Is this intentional?

I suspect not, but Martin is the one to answer.
If you had started a new thread for this new topic
"3.1 Windows Installer trashes extension registrations"
this would have been seen more easily ;-)



From mwilson at the-wire.com  Fri Jul  3 15:08:35 2009
From: mwilson at the-wire.com (Mel)
Date: Fri, 03 Jul 2009 15:08:35 -0400
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
	<025db26e$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2lkc3$31c$1@services.telesweet.net>

Steven D'Aprano wrote:

> The most important difference between my suggestion and that of the OP is
> that he limited the key function to something which returns a truth
> value, while I'm looking for something more general which can split the
> input into an arbitrary number of collated sublists.

Generally along the lines of

def scatter (seq, criterion):
    lists = {}
    for s in seq:
        lists.setdefault (criterion (s), []).append (s)
    return lists

modulo a defaultdict or some such ?

	Mel.
> 
> 
> 




From dudeja.rajat at gmail.com  Fri Jul  3 15:10:06 2009
From: dudeja.rajat at gmail.com (dudeja.rajat at gmail.com)
Date: Sat, 4 Jul 2009 00:40:06 +0530
Subject: [Help] Python implmenentation of finding process's command line 
	parameters.
Message-ID: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>

I'm looking for some python implementation of finding the command line
parameters of a process on Windows XP SP3 machine. I found some links but
they all point me to the direction of c/c++ implememtations.

I've seen WMI, but this takes time to load. So I just though if some one has
done implementation and could pointing me in some right direction.

Regards,
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/c6b10247/attachment.html>

From nosklo at gmail.com  Fri Jul  3 15:12:39 2009
From: nosklo at gmail.com (Clovis Fabricio)
Date: Fri, 3 Jul 2009 16:12:39 -0300
Subject: Python debugger
In-Reply-To: <4A19FA5C-C135-480F-BFD1-82B7AF1500A8@kagi.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
	<4A19FA5C-C135-480F-BFD1-82B7AF1500A8@kagi.com>
Message-ID: <9187a60d0907031212m7f91024m46b7d440e0815f29@mail.gmail.com>

2009/7/3 Kee Nethery <kee at kagi.com>:
> It's not free but I like the debugger in Komodo IDE.
> Lets me simulate a web connection, lets me step through the code and examine
> the variables as it executes, can be run remotely (have not played with that
> aspect yet).
> Does variable inspection of the variables so you can dive into the parts of
> arrays and dictionaries to see what the (for example) 5th item of the 4th
> item named "blah" is set to and what type of data element it is (int,
> unicode, etc). I find it tremendously useful as a newbie to Python.
> Kee Nethery

Winpdb is free and offers all those features.


From mail at timgolden.me.uk  Fri Jul  3 15:15:37 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 03 Jul 2009 20:15:37 +0100
Subject: [Help] Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
Message-ID: <4A4E58D9.6050806@timgolden.me.uk>

dudeja.rajat at gmail.com wrote:
> I'm looking for some python implementation of finding the command line
> parameters of a process on Windows XP SP3 machine. I found some links but
> they all point me to the direction of c/c++ implememtations.
> 
> I've seen WMI, but this takes time to load. So I just though if some one has
> done implementation and could pointing me in some right direction.

Someone recently posted an example using PSI [1] which seemed
quite fast.

TJG

[1] http://www.psychofx.com/psi/trac/wiki/


From mr.spoon21 at gmail.com  Fri Jul  3 15:23:20 2009
From: mr.spoon21 at gmail.com (Mr.SpOOn)
Date: Fri, 3 Jul 2009 21:23:20 +0200
Subject: Getting input the scanf way
In-Reply-To: <fcc576d0-46d7-4522-bfae-c60d53fb55fa@g1g2000yqh.googlegroups.com>
References: <mailman.2438.1246467374.8015.python-list@python.org>
	<fcc576d0-46d7-4522-bfae-c60d53fb55fa@g1g2000yqh.googlegroups.com>
Message-ID: <8f67b6f80907031223u767044ara169ddf137b5207a@mail.gmail.com>

Thanks, I think raw_input() will work just fine for my needs.


From tjreedy at udel.edu  Fri Jul  3 15:23:47 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 15:23:47 -0400
Subject: Sequence splitting
In-Reply-To: <e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
	<e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
Message-ID: <h2lls4$aep$1@ger.gmane.org>

Brad wrote:
> On Jul 2, 8:17 pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>> This sounds like it belongs to the python-ideas list.  I suggest
>> posting there for better feedback, since the core developers check
>> that list more often than this one.
> 
> I tried posting on python-ideas and received a "You are not allowed to
> post to this mailing list" reply. Perhaps because I am posting through
> Google groups? Or maybe one must be an approved member to post?

Spammers post thru Google groups

Either subscribe or access via news.gmane.org as gmane.comp.python.ideas.

As to your main question: this was discuss some years ago. There did not 
seem enough use cases for 'bifilter' or 'distributor' to warrent 
inclusion in the stdlib. Easy enough to do on one's own for those few 
cases. Just filter twice.

Usually, one wants to do one thing or another to each item with the 
original scan

for item in collection:
   if pred(item):
     proc_true(item)
   else:
     proc_false(item)

Having proc_true and proc_false both be append(item) is a special case.

Note that filter has been changed from returning a list to returning an 
iterator.  So a proposal for a function to return two lists would seem 
backwards. A function that returns two iterators would be possible. 
Something like itertools.tee except that each item would go on one tee 
or the other instead of both. It would have two queues (deques) instead 
of one. And it should be lazy -- items should only be pulled from the 
original iterator when an item is requested from an empty queue.

I am not sure it is worth it. In the worst case, all items are say 
'True' and you request 'False' items and all items get copied to the 
True queue before the False iterator raised StopIteration.

The way to avoid calling keyfunc(item) twice on each item is to make a 
new list first: newlist = list(map(keyfunc,iterable)). Then scan newlist 
twice.

If you write such a function, first in Python, then C, you can register 
code on PyPI and see how much interest it gets.

Terry Jan Reedy



From tjreedy at udel.edu  Fri Jul  3 15:27:25 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 15:27:25 -0400
Subject: Sequence splitting
In-Reply-To: <7xr5wx8zaf.fsf@ruckus.brouhaha.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<mailman.2537.1246591108.8015.python-list@python.org>	<025dab69$0$20657$c3e8da3@news.astraweb.com>	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
	<7xr5wx8zaf.fsf@ruckus.brouhaha.com>
Message-ID: <h2lm2t$aep$2@ger.gmane.org>

Paul Rubin wrote:
> Brad <schickb at gmail.com> writes:
>> Maybe this would be difficult to get into the core, but how about this
>> idea: Rename the current filter function to something like "split" or
>> "partition" (which I agree may be a better name) and modify it to
>> return the desired true and false sequences. Then recreate the
>> existing "filter" function with a wrapper that throws away the false
>> sequence.
> 
> This isn't so attractive, since filter takes a sequence input but
> returns a list. 

In modern Python (py3), it returns an iterator.



From gnewsg at gmail.com  Fri Jul  3 15:33:48 2009
From: gnewsg at gmail.com (Giampaolo Rodola')
Date: Fri, 3 Jul 2009 12:33:48 -0700 (PDT)
Subject: Python implmenentation of finding process's command line 
	parameters.
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com> 
	<mailman.2576.1246648542.8015.python-list@python.org>
Message-ID: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>

On 3 Lug, 21:15, Tim Golden <m... at timgolden.me.uk> wrote:
> dudeja.ra... at gmail.com wrote:
> > I'm looking for some python implementation of finding the command line
> > parameters of a process on Windows XP SP3 machine. I found some links but
> > they all point me to the direction of c/c++ implememtations.
>
> > I've seen WMI, but this takes time to load. So I just though if some one has
> > done implementation and could pointing me in some right direction.
>
> Someone recently posted an example using PSI [1] which seemed
> quite fast.
>
> TJG
>
> [1]http://www.psychofx.com/psi/trac/wiki/

If I'm not mistaken psi shouldn't support Windows.
You can use psutil:
http://code.google.com/p/psutil/

 >>> import psutil
 >>> p = psutil.Process(7055)
 >>> p.cmdline
 ['/usr/bin/python', '-O']
 >>>

--- Giampaolo
http://code.google.com/p/pyftpdlib
http://code.google.com/p/psutil/


From http  Fri Jul  3 15:41:20 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 12:41:20 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
	<7xr5wx8zaf.fsf@ruckus.brouhaha.com>
	<mailman.2579.1246649405.8015.python-list@python.org>
Message-ID: <7xr5wximfz.fsf@ruckus.brouhaha.com>

Terry Reedy <tjreedy at udel.edu> writes:
> > This isn't so attractive, since filter takes a sequence input but
> > returns a list.
> 
> In modern Python (py3), it returns an iterator.

Still not much help in the proposed version that would return two
iterators.  


From dudeja.rajat at gmail.com  Fri Jul  3 15:41:30 2009
From: dudeja.rajat at gmail.com (dudeja.rajat at gmail.com)
Date: Sat, 4 Jul 2009 01:11:30 +0530
Subject: Python implmenentation of finding process's command line 
	parameters.
In-Reply-To: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
Message-ID: <e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com>

I have had a look at psutil, however, this only works with Python 2.6.x and
above. We are using Python 2.5.2 and updating python could pose certain
problems. So, I'm not keep on using psutils.

-- 
Regrads,
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/ab27f706/attachment.html>

From mail at timgolden.me.uk  Fri Jul  3 15:48:20 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 03 Jul 2009 20:48:20 +0100
Subject: Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
Message-ID: <4A4E6084.6030001@timgolden.me.uk>

Giampaolo Rodola' wrote:
> On 3 Lug, 21:15, Tim Golden <m... at timgolden.me.uk> wrote:
>> dudeja.ra... at gmail.com wrote:
>>> I'm looking for some python implementation of finding the command line
>>> parameters of a process on Windows XP SP3 machine. I found some links but
>>> they all point me to the direction of c/c++ implememtations.
>>> I've seen WMI, but this takes time to load. So I just though if some one has
>>> done implementation and could pointing me in some right direction.
>> Someone recently posted an example using PSI [1] which seemed
>> quite fast.
>>
>> TJG
>>
>> [1]http://www.psychofx.com/psi/trac/wiki/
> 
> If I'm not mistaken psi shouldn't support Windows.
> You can use psutil:
> http://code.google.com/p/psutil/

Sorry. Exactly what I meant. (Should have checked for
the exact post rather than trusting to my memory).

TKG


From mail at timgolden.me.uk  Fri Jul  3 15:48:32 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 03 Jul 2009 20:48:32 +0100
Subject: Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
Message-ID: <4A4E6090.4060102@timgolden.me.uk>

Giampaolo Rodola' wrote:
> On 3 Lug, 21:15, Tim Golden <m... at timgolden.me.uk> wrote:
>> dudeja.ra... at gmail.com wrote:
>>> I'm looking for some python implementation of finding the command line
>>> parameters of a process on Windows XP SP3 machine. I found some links but
>>> they all point me to the direction of c/c++ implememtations.
>>> I've seen WMI, but this takes time to load. So I just though if some one has
>>> done implementation and could pointing me in some right direction.
>> Someone recently posted an example using PSI [1] which seemed
>> quite fast.
>>
>> TJG
>>
>> [1]http://www.psychofx.com/psi/trac/wiki/
> 
> If I'm not mistaken psi shouldn't support Windows.
> You can use psutil:
> http://code.google.com/p/psutil/

Sorry. Exactly what I meant. (Should have checked for
the exact post rather than trusting to my memory).

TJG


From tjgolden at gmail.com  Fri Jul  3 15:50:04 2009
From: tjgolden at gmail.com (Tim Golden)
Date: Fri, 03 Jul 2009 20:50:04 +0100
Subject: Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>	<mailman.2576.1246648542.8015.python-list@python.org>	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
	<e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com>
Message-ID: <4A4E60EC.7030400@gmail.com>

dudeja.rajat at gmail.com wrote:
> I have had a look at psutil, however, this only works with Python 2.6.x and
> above. We are using Python 2.5.2 and updating python could pose certain
> problems. So, I'm not keep on using psutils.

Doesn't look as if there's anything 2.6-specific there.
Maybe the maintainer can comment, but I suspect you'd
just need to recompile and link against 2.5

TJG


From tjreedy at udel.edu  Fri Jul  3 15:51:56 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 15:51:56 -0400
Subject: pep 8 constants
In-Reply-To: <4A4E135E.5090400@harvee.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
	<4A4E135E.5090400@harvee.org>
Message-ID: <h2lngt$eub$1@ger.gmane.org>

Eric S. Johansson wrote:
> Horace Blegg wrote:
>> I've been kinda following this. I have a cousin who is permanently wheel
>> chair bound and doesn't have perfect control of her hands, but still
>> manages to use a computer and interact with society. However, the
>> idea/thought of disabled programmers was new to me/hadn't ever occurred
>> to me.
>>
>> You say that using your hands is painful, but what about your feet?
>> Wouldn't it be possible to rig up some kind of foot peddle for
>> shift/caps lock? Kinda like the power peddle used with sowing machines,
>> so the hands are free to hold fabric.
>>
>> I don't mean this in a condescending manor, and I apologize if you take
>> it as such. I'm genuinely curious if you think something like this could
>> work.
>>
>> The way I was envisioning it working last night (and I haven't the
>> faintest clue how SR works, nor have I ever used SR) was that you would
>> hit the foot peddle, which would tell the SR program to capitalize the
>> first letter of the next word (a smart shift, basically, so you don't
>> end up doing something like ... WONderland -or- "stocks are up 1,0))%
>> TOday".)
>>
>> Possible? Stupid?
>>
> it's not stupid.
> 
> People have used foot pedals for decades for a variety of controls. I don't
> think foot pedals would work for me because when I am dictating, I pace.
> Standing, sitting, I pace. With a cord headset, I'm forced to stay within about
> 4 feet of the computer. But what I'm using a Bluetooth headset, I will sometimes
> ramble as far as 10 or 15 feet from the computer. It helps if I make the font
> larger so I can glance over and see what kind of errors I've gotten.
> 
> I really love a Bluetooth headset with speech recognition. It's so liberating.
> 
> Your question about foot pedals makes me think of alternative. would it make
> sense to have a handheld keyboard which would be used for command-and-control
> functionality or as an adjunct to speech recognition use? It would have to be
> designed in such a way that it doesn't aggravate a hand injury which may not be
> possible. Anyway, just thinking out loud.

As long as we are thinking wildly, how about a pair of 
bluetooth-connected switches on a belt or chest band that you could 
press with your arms or elbows -- no hands involved. Sort of become a 
walking mouse ;-).

Terry




From gnewsg at gmail.com  Fri Jul  3 15:57:44 2009
From: gnewsg at gmail.com (Giampaolo Rodola')
Date: Fri, 3 Jul 2009 12:57:44 -0700 (PDT)
Subject: Python implmenentation of finding process's command line 
	parameters.
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com> 
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
	<e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com> 
	<mailman.2583.1246650608.8015.python-list@python.org>
Message-ID: <ee71ca3b-c79f-461e-9fcc-dc57ef71966a@n11g2000yqb.googlegroups.com>

On 3 Lug, 21:50, Tim Golden <tjgol... at gmail.com> wrote:

> Sorry. Exactly what I meant. (Should have checked for
> the exact post rather than trusting to my memory)

No prolem.

> dudeja.ra... at gmail.com wrote:
> > I have had a look at psutil, however, this only works with Python 2.6.x and
> > above. We are using Python 2.5.2 and updating python could pose certain
> > problems. So, I'm not keep on using psutils.
>
> Doesn't look as if there's anything 2.6-specific there.
> Maybe the maintainer can comment, but I suspect you'd
> just need to recompile and link against 2.5
>
> TJG

psutil works on Python 2.4, 2.5 and 2.6.
If you are on Windows, you can get the precompiled binary for Python
2.5 from here:
http://code.google.com/p/psutil/downloads/list


--- Giampaolo
http://code.google.com/p/pyftpdlib
http://code.google.com/p/psutil/


From sajmikins at gmail.com  Fri Jul  3 16:04:21 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 13:04:21 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net> 
	<529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com> 
	<vgh3m.2329$ze1.1542@news-server.bigpond.net.au>
Message-ID: <c6c65f65-3279-42b9-b349-340a15ad6e65@y7g2000yqa.googlegroups.com>

On Jul 3, 2:09?am, Lie Ryan <lie.1... at gmail.com> wrote:
> Simon Forman wrote:
> > On Jul 2, 3:57 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> >> Duncan Booth wrote:
> >>> Simon Forman <sajmik... at gmail.com> wrote:
> >>>> ...
> >>>> if self.higher is self.lower is None: return
> >>>> ...
> >>> As a matter of style however I wouldn't use the shorthand to run two 'is'
> >>> comparisons together, I'd write that out in full if it was actually needed
> >>> here.
> >> Speaking only to the style issue, when I've wanted to do something like
> >> that, I find:
>
> >> ? ? ? ?if self.higher is None is self.lower:
> >> ? ? ? ? ? ?...
>
> >> more readable, by making clear they are both being compared to a
> >> constant, rather than compared to each other.
>
> > I was going to do it that way for aesthetics if nothing else, but in
> > this particular code "self.higher is self.lower" could only have been
> > True if they were both None, so the final "is None" was redundant and
> > I only included it as a "just-in-case" check in case someone someday
> > used the code in such a way as to assign the same object (not None) to
> > both self.higher and self.lower... ?Totally pointless, I'm sorry to
> > say. ?I'm glad the whole line was redundant really.
>
> I say, you should keep the `is None` for readability and to safe guard
> against immutable optimization and/or Singleton objects. Due to an
> implementation detail, python does not guarantee that two immutable
> object will return different objects; you have:
>
> >>> a = 1
> >>> b = 1
> >>> a is b
>
> True

I probably would have kept the 'is None' for those reasons except that
this code was never meant to be used by anyone but me, and it turned
out the entire line was redundant anyway. :]


From python at mrabarnett.plus.com  Fri Jul  3 16:07:50 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 21:07:50 +0100
Subject: Sequence splitting
In-Reply-To: <h2lkc3$31c$1@services.telesweet.net>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<mailman.2537.1246591108.8015.python-list@python.org>	<025dab69$0$20657$c3e8da3@news.astraweb.com>	<7x1voy5h3j.fsf@ruckus.brouhaha.com>	<025db26e$0$20657$c3e8da3@news.astraweb.com>
	<h2lkc3$31c$1@services.telesweet.net>
Message-ID: <4A4E6516.8090207@mrabarnett.plus.com>

Mel wrote:
> Steven D'Aprano wrote:
> 
>> The most important difference between my suggestion and that of the OP is
>> that he limited the key function to something which returns a truth
>> value, while I'm looking for something more general which can split the
>> input into an arbitrary number of collated sublists.
> 
> Generally along the lines of
> 
> def scatter (seq, criterion):
>     lists = {}
>     for s in seq:
>         lists.setdefault (criterion (s), []).append (s)
>     return lists
> 
> modulo a defaultdict or some such ?
> 
Somehow this reminds me of the new Counter class, except that it's
making lists instead of counts.


From user at example.net  Fri Jul  3 16:14:22 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 22:14:22 +0200
Subject: stringio+tarfile (or better... zipfile)
In-Reply-To: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <4a4e66a0$0$1115$4fafbaef@reader4.news.tin.it>

following the excellent suggestions received, i tried to adapt the 
problem to zipfile, and i wrote this:

$ cat zip001.py
import sys
import zipfile
import StringIO

nb1 = "first.txt", StringIO.StringIO("one one\n")
nb2 = "second.txt", StringIO.StringIO("two\n")
zb = StringIO.StringIO()

zip = zipfile.ZipFile(zb , "w" , zipfile.ZIP_DEFLATED)

for name , buffer in [nb1 , nb2]:
     zip.writestr(name, buffer.getvalue()*1000)
zip.close()

sys.stdout.write(zb.getvalue())
$ python zip001.py > zip001.out
$ unzip -l zip001.out
Archive:  zip001.out
   Length     Date   Time    Name
  --------    ----   ----    ----
      8000  07-03-09 22:07   first.txt
      4000  07-03-09 22:07   second.txt
  --------                   -------
     12000                   2 files
$

it seems to me thaz zipfile has a simpler usability... any comments?

thanks again and bye bye


From sajmikins at gmail.com  Fri Jul  3 16:17:16 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 13:17:16 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
Message-ID: <2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>

On Jul 3, 12:56?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> writes:
> > > Yes, but the concept of null pointers is considered kludgy these days.
> > Seriously? "kludgy"? ?(I really AM getting old.)
>
> ?http://math.andrej.com/2009/04/11/on-programming-language-design/
>
> discusses the issue (scroll down to "Undefined values" section).

Hmm, I'm not convinced.  I read that post with interest, but his
argument against None et. al. was just this:

"...stick to the principle: NULL is wrong because it causes horrible
and tricky mistakes which appear even after the program was tested
thoroughly. You cannot introduce NULL into the language and tell the
programmer to be careful about it. The programmer is not capable of
being careful!"

To me that seems weak and too general, you could say /anything/
"...causes horrible and tricky mistakes which appear even after the
program was tested thoroughly."

He does go on to say, in a reply to a comment, "In my opinion, at the
end of the day the quality of the code depends more on the quality of
its author than on the quality of the language he uses. But this does
not mean that the quality of the programming language does not
matter."

Which I agree with wholeheartedly.  I just don't see that he made a
strong case that the inclusion of NULLs directly implies poor quality
of language.

(I like Haskell's Maybe, but saying A is better than B doesn't imply
that B is therefore terrible.)



> > Well I wouldn't know, I've been fortunate enough to program mostly in
> > python for over half a decade now and None and 0 are as close as I've
> > gotten to NULL in a long time.
>
> Right, and how many times have you had to debug
>
> ? ?AttributeError: 'NoneType' object has no attribute 'foo'
>
> or the equivalent null pointer exceptions in Java, C, or whatever?
> They are very common. ?And the basic idea is that if you avoid using
> null pointers in the first place, you'll get fewer accidental null
> pointer exceptions.

I have encountered exceptions like that, but usually as a result of
e.g. omitting a return statement (so the caller gets None instead of
whatever should have been returned.)

I don't usually write "pointer" style code in python. In fact, other
than this BTree and the Dancing Links algorithm I mentioned earlier I
can't recall ever having done it.  Indeed, python's omission of
pointers is one of the reasons I'm so fond of it.

In my experience with python exceptions like that one are indicators
of something bad wrong with my code, not of misuse of None (as NULL
pointer.)



> > That sounds very interesting, but I'm only writing a BTree to then use
> > it to play with "persistent data structures"
>
> But you have implemented a mutable tree. ?If you want to write a
> persistent one, then write a persistent one! ?You also use a wishful

The paper I'm working from is about general techniques for making
persistent data structures from mutable forms, thus I wanted a mutable
BTree to then "overwrite" with a persistent form.


> heuristic in the hope of keeping the tree balanced--if you want a
> balanced tree, why not use one that's guaranteed to stay in balance?
> AVL trees are pretty easy to implement; maybe you could try writing a
> persistent one:
>
> ?http://en.wikipedia.org/wiki/AVL_tree

The balance (or lack thereof) of the tree is not important (in this
use.) I threw in that heuristic in the delete function because it was
easy enough and it was mentioned in the wikipedia article on BTrees.
AVL trees are easy too, but still more complicated than I need.


> > In this particular case it's somewhat more elegant (IMO) to check "is
> > None".
>
> Well, I can't understand why that might be, but it's surely
> subjective, so ok.

It's a matter of this:

if a is None:
    return b
if b is None:
    return a
# handle both non-None here...

vs. this:

if a is not None:
    if b is not None:
        # handle both non-None here...
    else:
        return a
return b

Everything is subjective, but I think the first one is more elegant
IMO.



> > > I'm sorry but I find that class rather ugly. ?The code would be a lot
> > > smaller and have fewer corner cases with a different data representation.
>
> > Um, thanks? ?Seriously though, care to put your money where your mouth
> > is? I'd be interested to see a BTree implemented as you indicated above.
>
> Er, I'm not trying to argue with you. ?You asked for people's advice
> and impressions, so I gave you some. ?I don't feel like rewriting that

I know, I asked for it. :] But it still stings a little to hear
someone call my code "rather ugly".  No hard feelings. I'm not trying
to argue with you either. :]


> whole class, but I'll do a method or two, using [] to represent an
> empty node. ?(Hmm, actually changing the empty node representation did
> less to shorten the code than just getting rid of a bunch of
> duplication. ?Really, I'd tend to look for a slightly different tree
> structure which tried to avoid these issues).

Hmm, I really don't see that using an empty list rather than None as a
stand-in for NULL pointer bought you anything there.  In fact, this
code would work identically if you replaced [] with None.

I was hoping to see some clever code-fu involving list manipulation or
something.  When would you ever store a value in the empty list
"nodes" anyway?

> Untested:
>
> class BinaryTree:
> ? ? def __init__(self, key, value):
> ? ? ? ? self.key = key
> ? ? ? ? self.value = value
> ? ? ? ? self.higher = self.lower = []
>
> ? ? def get(self, key):
> ? ? ? ? if key == self.key:
> ? ? ? ? ? ? return self.value
> ? ? ? ? branch = self.lower if key < self.key else self.higher
> ? ? ? ? return branch.get(key) if branch else []
>
> ? ? def insert(self, key, value):
> ? ? ? ? def xinsert(xtree): ?# xtree is either a tree or []
> ? ? ? ? ? ?if not xtree: xtree = BinaryTree(key, value)
> ? ? ? ? ? ?else: xtree.insert(key, value)
> ? ? ? ? ? ?return xtree
>
> ? ? ? ? if key == self.key:
> ? ? ? ? ? ? self.value = value
> ? ? ? ? elif key < self.key:
> ? ? ? ? ? ? self.lower = xinsert(self.lower)
> ? ? ? ? else:
> ? ? ? ? ? ? self.higher = xinsert(self.higher)
>
> and so forth.



From dickinsm at gmail.com  Fri Jul  3 16:18:09 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Fri, 3 Jul 2009 13:18:09 -0700 (PDT)
Subject: Compiling 64 bit python on a mac - cannot compute sizeof (int)
References: <b118d0f7-c997-4182-b734-8d39d84016d3@g7g2000prg.googlegroups.com>
Message-ID: <6c0287d8-c9f5-44e2-8159-fe5c88494a62@g1g2000yqh.googlegroups.com>

On Jul 3, 5:30?pm, Keflavich <keflav... at gmail.com> wrote:
> I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X
> 10.5.7), and am running into a problem during the configure stage.
>
> I configure with:
> ./configure --enable-framework=/Library/Frameworks --enable-
> universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all -
> with-readline-dir=/usr/local
>
> because I want 64 and 32 bit, and I needed to install a 64 bit
> readline as a prerequisite.
>
> configure fails at:
> checking size of int... configure: error: cannot compute sizeof (int)

I confess that I don't fully understand the intricacies of the various
OS X autoconf options, but I think the problem is that the --enable-
universalsdk option takes a directory.  If that directory isn't
given, it appears to default to /Developer/SDKs/MacOSX10.4u.sdk (at
least on my OS X 10.5.7 machine), which would likely conflict with
your MACOSX_DEPLOYMENT_TARGET=10.5 setting.

Try either changing MACOSX_DEPLOYMENT_TARGET to 10.4, or using --
enable-universalsdk=/Developer/SDKs/MacOSX10.5.sdk  (or whatever the
appropriate directory is on your system).  For some reason, I think
using --enable-universalsdk=/ also works on my system.  If none of
that helps, you might try asking this question over on the pythonmac-
sig mailing list. (http://mail.python.org/mailman/listinfo/pythonmac-
sig)

Mark


From timr at probo.com  Fri Jul  3 16:20:18 2009
From: timr at probo.com (Tim Roberts)
Date: Fri, 03 Jul 2009 13:20:18 -0700
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<4A4CA278.4050604@ieee.org> <h2i84f$v2t$1@ger.gmane.org>
	<mailman.2491.1246540910.8015.python-list@python.org>
Message-ID: <ftps459nklqio3nghaaraniqo3fs9r8ck8@4ax.com>

Dave Angel <davea at dejaviewphoto.com> wrote:
>   
>You're right of course.  What I was trying to say was it deletes the 
>reference to the object.  Unlike obj = None, del obj removes the 
>reference (attribute) entirely. Although I don't know what it should be 
>called if it's a local variable.  Perhaps it "unbinds" the name.

Yes.  As far as the object is concerned, "obj = None" and "del obj" are
exactly identical.  In both cases, there is one less binding to the name.

The difference between the two is only whether the name lives on in the
namespace.

A local variable is (usually) just a name in the local() namespace.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From tjreedy at udel.edu  Fri Jul  3 16:36:50 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 16:36:50 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <025e3974$0$20657$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<025e3974$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2lq52$lp0$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 03 Jul 2009 16:19:22 +0000, kj wrote:
> 
>> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac
>> <alan.isaac at gmail.com> writes:
>>
>>> 1. Don't use assertions to test argument values!
>> Out of curiosity, where does this come from?
> 
> Assertions are disabled when you run Python with the -O (optimise) flag. 
> If you rely on assertions to verify data, then any time the user runs 
> python with -O your code will be running without error checking.
> 
> assert should be used to verify program logic, not to sanitize data.

In other words, assertions should never happen, whereas your assertions 
could easily happen with 'bad' input. An example of program logic 
assertion would be 'assert <loop-invariant>' at the top of the loop. 
That would be useful for development, but would not be needed for 
production use of tested code.

tjr




From sajmikins at gmail.com  Fri Jul  3 16:46:28 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 13:46:28 -0700 (PDT)
Subject: Python debugger
References: <mailman.2555.1246623750.8015.python-list@python.org>
Message-ID: <ae885a04-6626-46e9-9480-5d7a8ce47218@h11g2000yqb.googlegroups.com>

On Jul 3, 8:15?am, srinivasan srinivas <sri_anna... at yahoo.co.in>
wrote:
> Hi,
> Could you suggest some python debuggers?
>
> Thanks,
> Srini
>
> ? ? ? Love Cricket? Check out live scores, photos, video highlights and more. Click herehttp://cricket.yahoo.com

Ipython has good debugger integration.


From http  Fri Jul  3 16:50:12 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 13:50:12 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
Message-ID: <7xhbxtjxtn.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> "...stick to the principle: NULL is wrong because it causes horrible
> and tricky mistakes which appear even after the program was tested
> thoroughly. You cannot introduce NULL into the language and tell the
> programmer to be careful about it. The programmer is not capable of
> being careful!"
> 
> To me that seems weak and too general, you could say /anything/
> "...causes horrible and tricky mistakes which appear even after the
> program was tested thoroughly."

On the contrary, general means powerful :).  For example, you can say
that malloc/free in C causes horrible and tricky mistakes etc.  Python
avoids the mistakes by having automatic storage management.

> Which I agree with wholeheartedly.  I just don't see that he made a
> strong case that the inclusion of NULLs directly implies poor quality
> of language.
> 
> (I like Haskell's Maybe, but saying A is better than B doesn't imply
> that B is therefore terrible.)

I wouldn't say Python's None is terrible, but the programming style in
which None is used as a marker for "absent value" is genuinely a
source of bugs, requiring care when used.  Often it's easy to just
avoid it and all the bugs that come with it.

Haskell's Maybe type, ML's Option type, and various similar constructs
in other recently designed languages all are responses to the
shortcomings of None-like constructs in older languages.  I'm not
going purely by that one guy's blog post, though I do think that post
was pretty good.

> Hmm, I really don't see that using an empty list rather than None as a
> stand-in for NULL pointer bought you anything there.  In fact, this
> code would work identically if you replaced [] with None.

Yes I noticed that too (and mentioned it) after writing the code.  I
think the real problem is that the class has unnatural semantics and
Python's OOP system (well, OOP in general) is also sort of kludgy.
I will think about a possible rewrite.


From keflavich at gmail.com  Fri Jul  3 19:01:42 2009
From: keflavich at gmail.com (Adam)
Date: Fri, 3 Jul 2009 16:01:42 -0700 (PDT)
Subject: Compiling 64 bit python on a mac - cannot compute sizeof (int)
References: <b118d0f7-c997-4182-b734-8d39d84016d3@g7g2000prg.googlegroups.com>
	<6c0287d8-c9f5-44e2-8159-fe5c88494a62@g1g2000yqh.googlegroups.com>
Message-ID: <73186719-e5a6-4661-a06c-cf6f2570996b@2g2000prl.googlegroups.com>

On Jul 3, 2:18?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 3, 5:30?pm, Keflavich <keflav... at gmail.com> wrote:
>
> > I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X
> > 10.5.7), and am running into a problem during the configure stage.
>
> > I configure with:
> > ./configure --enable-framework=/Library/Frameworks --enable-
> > universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all -
> > with-readline-dir=/usr/local
>
> > because I want 64 and 32 bit, and I needed to install a 64 bit
> > readline as a prerequisite.
>
> > configure fails at:
> > checking size of int... configure: error: cannot compute sizeof (int)
>
> I confess that I don't fully understand the intricacies of the various
> OS X autoconf options, but I think the problem is that the --enable-
> universalsdk option takes a directory. ?If that directory isn't
> given, it appears to default to /Developer/SDKs/MacOSX10.4u.sdk (at
> least on my OS X 10.5.7 machine), which would likely conflict with
> your MACOSX_DEPLOYMENT_TARGET=10.5 setting.
>
> Try either changing MACOSX_DEPLOYMENT_TARGET to 10.4, or using --
> enable-universalsdk=/Developer/SDKs/MacOSX10.5.sdk ?(or whatever the
> appropriate directory is on your system). ?For some reason, I think
> using --enable-universalsdk=/ also works on my system. ?If none of
> that helps, you might try asking this question over on the pythonmac-
> sig mailing list. (http://mail.python.org/mailman/listinfo/pythonmac-
> sig)
>
> Mark

Thanks.  I also determined after the fact that universalsdk was the
problem, but I didn't know how to fix it.  Unfortunately, it turns out
what you identified was a transcription error on my part - I had been
using --enable-universalsdk instead of --enable-universalsdk=/.
Thanks for the help, I appreciate it!

Adam


From alan.isaac at gmail.com  Fri Jul  3 19:18:15 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 23:18:15 GMT
Subject: 3.1 Windows Installer trashes extension registrations
In-Reply-To: <mailman.2573.1246647459.8015.python-list@python.org>
References: <mailman.2526.1246576243.8015.python-list@python.org>	<Hue3m.534$P5.391@nwrddc02.gnilink.net>
	<mailman.2573.1246647459.8015.python-list@python.org>
Message-ID: <Xkw3m.688$P5.676@nwrddc02.gnilink.net>

> Alan G Isaac wrote:
>> Using the 3.1 Windows installer, I chose that I did not 
>> want the extensions registered, and the installer 
>> unregistered the .py and .pyw extensions (which I had 
>> wanted to keep associated with Python 2.6).
>> Is this intentional?


On 7/3/2009 2:57 PM Terry Reedy apparently wrote:
> I suspect not, but Martin is the one to answer. 
> If you had started a new thread for this new topic 
> "3.1 Windows Installer trashes extension registrations"
> this would have been seen more easily ;-)


Done.

Cheers,
Alan Isaac


From gallium.arsenide at gmail.com  Fri Jul  3 19:26:39 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Fri, 3 Jul 2009 16:26:39 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
Message-ID: <9d99c5ca-f497-473f-a22f-a5219597bcd7@h11g2000yqb.googlegroups.com>

On Jul 3, 4:50?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> I wouldn't say Python's None is terrible, but the
> programming style in which None is used as a marker
> for "absent value" is genuinely a source of bugs,
> requiring care when used. ?Often it's easy to just
> avoid it and all the bugs that come with it.

While other languages may make it easier to avoid these types of bugs,
I think it's pretty natural to use Python's None as a marker for
"absent value", if you're coding in Python.  Python seems to encourage
this by having functions return None when there is no explicit return
value, and by having the interactive command line print nothing at all
when the expression evaluates to None.

I won't argue with anyone who wants to call these design flaws, but it
seems to me that using None this way in one's own Python code is
reasonably Pythonic.

John


From tn.pablo at gmail.com  Fri Jul  3 19:40:03 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Fri, 3 Jul 2009 18:40:03 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <fdd00b510907031640y3b98604fo3c26dc8695ed8fef@mail.gmail.com>

On Fri, Jul 3, 2009 at 09:05, kj<no.email at please.post> wrote:
> The context is the concept of a binary search. ?In one of their
> homeworks, my students will have two occasions to use a binary
> search. ?This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.

Five params for a novice function is overkill.  I'd drop the epsilon
thing and, assuming you are searching in a list, tuple or something
similar, make the lower limit default to the first index and the upper
default to the last one.

In fact, I'd let them to realize that a function is convenient, and
base some of the grading in whether they wrote it or not.  Just a
thought.

-- 
Pablo Torres N.


From ldo at geek-central.gen.new_zealand  Fri Jul  3 20:08:17 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sat, 04 Jul 2009 12:08:17 +1200
Subject: Idioms and Anti-Idioms Question
References: <mailman.1932.1245644100.8015.python-list@python.org>
	<H0F%l.20231$y61.5030@news-server.bigpond.net.au>
	<slrnh402pc.deb.peter@box8.pjb.com.au>
	<mailman.2018.1245772229.8015.python-list@python.org>
	<h2erl2$h7l$1@lust.ihug.co.nz>
	<mailman.2493.1246544869.8015.python-list@python.org>
Message-ID: <h2m6hi$q81$1@lust.ihug.co.nz>

In message <mailman.2493.1246544869.8015.python-list at python.org>, J. Cliff 
Dyer wrote:

> On Wed, 2009-07-01 at 17:19 +1200, Lawrence D'Oliveiro wrote:
>>
>> In message <mailman.2018.1245772229.8015.python-list at python.org>, J.
>> Cliff Dyer wrote:
>> 
>> > If the lines got separated, a leading + could disappear into its line
>> > without any errors showing up.  A trailing + would raise a syntax
>> > error.
>> 
>> Unless, of course, it was moved onto the previous line as part of
>> whatever caused the separation of the lines. How would you guard against
>> that?
> 
> Can you give an example of what you mean?

Sure. Just start with an example of what you mean.



From asm198 at gmail.com  Fri Jul  3 21:14:23 2009
From: asm198 at gmail.com (Icarus)
Date: Fri, 3 Jul 2009 18:14:23 -0700 (PDT)
Subject: Problems with using queue in Tkinter application
Message-ID: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>

I'm working on a serial protocol analyzer in python.  We have an
application written by someone else in MFC but we need something that
is cross platform.  I intended to implement the GUI portion in Tkinter
but am having trouble.

The idea is that I will read messages from the serial port and output
them to a Tkinter Text object initially.  Eventually it will have
other functionality but that's it for the short term.  I've written
this little test app to experiment with putting things on the GUI via
a Queue which is polled by the Tkinter loop.

On some machines this code works fine and I get whatever I type in
displayed in the Text widget.  On others I get errors like this as
soon as I start it running.

error in background error handler:
out of stack space (infinite loop?)
    while executing
"::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
    while execu..."


I don't understand why on some machines it works exactly as expected
and on others it acts the same way Tkinter does when I call functions
directly from outside the Tkinter thread.  Does anyone have any
suggestions?  The full code as appended below.  Thanks in advance.

[code]

import Queue

class functionQueue:

    def __init__(self, root = None, timeout = 250):

        self.functionQueue = Queue.Queue()
        self.root = root
        self.timeout = timeout

        if(self.root):
            self.pop_function(root)


    def pop_function(self, root = None):

        try:
            funcArgList = self.functionQueue.get(block = False)
        except Queue.Empty:
            pass
        else:
            try:
                funcArgList[0](*funcArgList[1])
            except:
                try:
                    print "Failed to call function", funcArgList[0]
                except:
                    print "Failed to call function"

        if(root):
            root.after(self.timeout, lambda: self.pop_function
(self.root))

    def add_function(self, function, argList):

        try:
            self.functionQueue.put([function, argList])
        except:
            pass


if( __name__ == '__main__'):

    import Tkinter
    import thread

    text = Tkinter.Text()
    text.pack()

    myQueue = functionQueue(text, 50)

    def gui_loop():
        try:
            text.mainloop()
        except:
            import os
            os._exit(1)

    thread.start_new_thread(text.mainloop, ())

    while(True):
        usrInput = raw_input()

        if(usrInput == "-1"):
            import os
            os._exit(0)

        myQueue.add_function(text.insert, ['end', usrInput + "\n"])
        myQueue.add_function(text.see, ['end'])

[/code]



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 22:04:42 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 02:04:42 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
Message-ID: <025eaa4f$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 13:50:12 -0700, Paul Rubin wrote:

> I wouldn't say Python's None is terrible, but the programming style in
> which None is used as a marker for "absent value" is genuinely a source
> of bugs, requiring care when used.  Often it's easy to just avoid it and
> all the bugs that come with it.

So you keep saying, but I don't believe it. I've never found this to be a 
problem in my own code: a few silly mistakes where I accidentally assign 
the result of a function that operates by side-effect:

blist = alist.sort()

or similar, and I haven't done that for years now.

No, wait, I tell I lie... re.search() sometimes bites me, because 
sometimes it returns None and sometimes it returns a matchobject and I 
don't use re often enough to have good habits with it yet. But that's a 
good example of why removing NULL (None, nul, nil, whatever you want to 
call it) doesn't lower the number of bugs, it just changes their nature: 
if re.search didn't return None, I'd still have trouble with it.

There are three natural approaches to (say) re.search() for dealing with 
failure:

(1) return a sentinel value like None;

(2) return a matchobject which tests False;

(3) raise an exception.

Here's how you would use them correctly:


# 1 or 2 are handled identically
o = re.search(s)
if o:
    process_match(o)
else:
    print "Not found"


# 3 is different
try:
    process_match(re.search(s))
except Exception:
    print "Not found"


There's essentially little or no difference in the handling. In all three 
cases, if you assume search will always succeed or forget to handle the 
failure case, you will write incorrect code:

process_match(re.search(s))

and get an unexpected exception. The only difference is that the specific 
exception will differ between the cases. Remove None from the scenario 
doesn't reduce the number of bugs, it just changes their nature.



-- 
Steven


From gagsl-py2 at yahoo.com.ar  Fri Jul  3 23:50:12 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 04 Jul 2009 00:50:12 -0300
Subject: stringio+tarfile (or better... zipfile)
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<4a4e66a0$0$1115$4fafbaef@reader4.news.tin.it>
Message-ID: <op.uwix9ym4x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 17:14:22 -0300, superpollo <user at example.net> escribi?:

> following the excellent suggestions received, i tried to adapt the  
> problem to zipfile, and i wrote this:
>
> zip = zipfile.ZipFile(zb , "w" , zipfile.ZIP_DEFLATED)
> for name , buffer in [nb1 , nb2]:
>      zip.writestr(name, buffer.getvalue()*1000)
> zip.close()
>
> it seems to me thaz zipfile has a simpler usability... any comments?

Maybe - but a zip and a tar file are not the same thing.

Now, if you want to say that there should be a common interfase to handle  
all those file formats like tar,zip,bz2: Yes, I agree.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Sat Jul  4 00:04:29 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 04 Jul 2009 01:04:29 -0300
Subject: Reversible Debugging
References: <4A4E4B8B.7090104@gmail.com>
Message-ID: <op.uwiyxrjtx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 15:18:51 -0300, Patrick Sabin  
<patrick.just4fun at gmail.com> escribi?:

> I am interested if there are any python modules, that supports  
> reversible debugging aka stepping backwards. Any links or ideas would be  
> helpful, because I am thinking of implementing something like that.

Do you want reverse execution, like an undo function? Undo all changes  
made by executing some piece of code?
There are many cases where that's hard to do, or impossible. How to undo  
object destruction? How to undo external effects, like writing to files?
You should think carefully what can and cannot be done - good luck!

-- 
Gabriel Genellina



From aahz at pythoncraft.com  Sat Jul  4 00:47:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 21:47:30 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
Message-ID: <h2mmt2$48p$1@panix3.panix.com>

In article <7xhbxtjxtn.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>Simon Forman <sajmikins at gmail.com> writes:
>> 
>> (I like Haskell's Maybe, but saying A is better than B doesn't imply
>> that B is therefore terrible.)
>
>I wouldn't say Python's None is terrible, but the programming style in
>which None is used as a marker for "absent value" is genuinely a
>source of bugs, requiring care when used.  Often it's easy to just
>avoid it and all the bugs that come with it.
>
>Haskell's Maybe type, ML's Option type, and various similar constructs
>in other recently designed languages all are responses to the
>shortcomings of None-like constructs in older languages.  I'm not
>going purely by that one guy's blog post, though I do think that post
>was pretty good.

AFAICT, in order for Maybe and Option to work, you need to have some
kind of static typing system.  Am I missing something?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From aahz at pythoncraft.com  Sat Jul  4 00:50:47 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 21:50:47 -0700
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<h2i84f$v2t$1@ger.gmane.org>
	<mailman.2491.1246540910.8015.python-list@python.org>
	<ftps459nklqio3nghaaraniqo3fs9r8ck8@4ax.com>
Message-ID: <h2mn37$hqp$1@panix3.panix.com>

In article <ftps459nklqio3nghaaraniqo3fs9r8ck8 at 4ax.com>,
Tim Roberts  <timr at probo.com> wrote:
>Dave Angel <davea at dejaviewphoto.com> wrote:
>>   
>>You're right of course.  What I was trying to say was it deletes the 
>>reference to the object.  Unlike obj = None, del obj removes the 
>>reference (attribute) entirely. Although I don't know what it should be 
>>called if it's a local variable.  Perhaps it "unbinds" the name.
>
>Yes.  As far as the object is concerned, "obj = None" and "del obj" are
>exactly identical.  In both cases, there is one less binding to the name.
>
>The difference between the two is only whether the name lives on in the
>namespace.
>
>A local variable is (usually) just a name in the local() namespace.

OTOH, Python's ``del`` applies to targets generally, not just names:

>>> L = [1,2,3]
>>> del L[1]
>>> L
[1, 3]
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From upwestdon at gmail.com  Sat Jul  4 02:03:39 2009
From: upwestdon at gmail.com (upwestdon)
Date: Fri, 3 Jul 2009 23:03:39 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>

On Jul 2, 1:23?pm, Simon Forman <sajmik... at gmail.com> wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
>
> ## First snippet
>
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
>
> ## Second snippet
>
> if self.higher is None:
> ? ? if self.lower is None:
> ? ? ? ? return
> ? ? return self.lower
> if self.lower is None:
> ? ? return self.higher
>
> What do you think?
>
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)

How about just:

if not (self.higher and self.lower):
    return self.higher or self.lower


From tkjthingone at gmail.com  Sat Jul  4 02:46:13 2009
From: tkjthingone at gmail.com (Horace Blegg)
Date: Fri, 3 Jul 2009 23:46:13 -0700
Subject: Reversible Debugging
In-Reply-To: <4A4E4B8B.7090104@gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
Message-ID: <b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>

You might consider using a VM with 'save-points'. You run the program (in a
debugger/ida/what have you) to a certain point (logical point would be
if/ifelse/else statements, etc) and save the VM state. Once you've saved,
you continue. If you find the path you've taken isn't what you are after,
you can reload a previous save point and start over, trying a different path
the next time.

This is also somewhat useful if you're trying to debug an error that happens
deep inside of a program, so you can continually jump to the point right
before the error happens, instead of needing to run through the entire
program each time it crashes. Just beware of tunnel vision.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/6180961d/attachment.html>

From hanooter at gmail.com  Sat Jul  4 03:33:52 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 00:33:52 -0700 (PDT)
Subject: finding most common elements between thousands of multiple arrays.
Message-ID: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>

Currently I need to find the most common elements in thousands of
arrays within one large array (arround 2 million instances with ~70k
unique elements)

so I set up a dictionary to handle the counting so when I am
iterating  I up the count on the corrosponding dictionary element. I
then iterate through the dictionary and find the 25 most common
elements.

the elements are initially held in a array within an array. so I am am
just trying to find the most common elements between all the arrays
contained in one large array.
my current code looks something like this:
d = {}
for arr in my_array:
-----for i in arr:
#elements are numpy integers and thus are not accepted as dictionary
keys
-----------d[int(i)]=d.get(int(i),0)+1

then I filter things down. but with my algorithm that only takes about
1 sec so I dont need to show it here since that isnt the problem.


But there has to be something better. I have to do this many many
times and it seems silly to iterate through 2 million things just to
get 25. The element IDs are integers and are currently being held in
numpy arrays in a larger array. this ID is what makes up the key to
the dictionary.

 It currently takes about 5 seconds to accomplish this with my current
algorithm.

So does anyone know the best solution or algorithm? I think the trick
lies in matrix intersections but I do not know.


From clp2 at rebertia.com  Sat Jul  4 03:45:32 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 00:45:32 -0700
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <50697b2c0907040045i5316c803ma199bfab10324735@mail.gmail.com>

On Sat, Jul 4, 2009 at 12:33 AM, mclovin<hanooter at gmail.com> wrote:
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
>
> so I set up a dictionary to handle the counting so when I am
> iterating ?I up the count on the corrosponding dictionary element. I
> then iterate through the dictionary and find the 25 most common
> elements.
>
> the elements are initially held in a array within an array. so I am am
> just trying to find the most common elements between all the arrays
> contained in one large array.
> my current code looks something like this:
> d = {}
> for arr in my_array:
> -----for i in arr:
> #elements are numpy integers and thus are not accepted as dictionary
> keys
> -----------d[int(i)]=d.get(int(i),0)+1
>
> then I filter things down. but with my algorithm that only takes about
> 1 sec so I dont need to show it here since that isnt the problem.
>
>
> But there has to be something better. I have to do this many many
> times and it seems silly to iterate through 2 million things just to
> get 25. The element IDs are integers and are currently being held in
> numpy arrays in a larger array. this ID is what makes up the key to
> the dictionary.
>
> ?It currently takes about 5 seconds to accomplish this with my current
> algorithm.
>
> So does anyone know the best solution or algorithm? I think the trick
> lies in matrix intersections but I do not know.

Using a defaultdict
(http://docs.python.org/library/collections.html#collections.defaultdict)
would speed it up (but only slightly) and make it clearer to read.

Cheers,
Chris
-- 
http://blog.rebertia.com


From patrick.just4fun at gmail.com  Sat Jul  4 04:04:08 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Sat, 04 Jul 2009 10:04:08 +0200
Subject: Reversible Debugging
In-Reply-To: <op.uwiyxrjtx6zn5v@lepton.softlabbsas.com.ar>
References: <4A4E4B8B.7090104@gmail.com>
	<op.uwiyxrjtx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A4F0CF8.5090101@gmail.com>

Gabriel Genellina schrieb:
> Do you want reverse execution, like an undo function? Undo all changes 
> made by executing some piece of code?
I am not completly sure, if I really want to make exact undo, i.e. 
undoing commands by reversing all their effects, or just restoring the
program state to an arbitrary state of its history, which would not 
effect things like files.
> There are many cases where that's hard to do, or impossible. How to 
> undo object destruction? How to undo external effects, like writing to 
> files?
Object destruction should not be a big problem to restore. But writing 
files or other resources is because it is not guaranted that it is even 
possible or wanted.
I considered either ignoring undoing external commands completly or 
adding some plugin system to do it.
> You should think carefully what can and cannot be done - good luck!
>


From andreengels at gmail.com  Sat Jul  4 04:04:42 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sat, 4 Jul 2009 10:04:42 +0200
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>

On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
>
> so I set up a dictionary to handle the counting so when I am
> iterating ?I up the count on the corrosponding dictionary element. I
> then iterate through the dictionary and find the 25 most common
> elements.
>
> the elements are initially held in a array within an array. so I am am
> just trying to find the most common elements between all the arrays
> contained in one large array.
> my current code looks something like this:
> d = {}
> for arr in my_array:
> -----for i in arr:
> #elements are numpy integers and thus are not accepted as dictionary
> keys
> -----------d[int(i)]=d.get(int(i),0)+1
>
> then I filter things down. but with my algorithm that only takes about
> 1 sec so I dont need to show it here since that isnt the problem.
>
>
> But there has to be something better. I have to do this many many
> times and it seems silly to iterate through 2 million things just to
> get 25. The element IDs are integers and are currently being held in
> numpy arrays in a larger array. this ID is what makes up the key to
> the dictionary.
>
> ?It currently takes about 5 seconds to accomplish this with my current
> algorithm.
>
> So does anyone know the best solution or algorithm? I think the trick
> lies in matrix intersections but I do not know.

There's no better algorithm for the general case. No method of
checking the matrices using less than 2000000-x look-ups will ensure
you that there's not a new value with x occurences lurking somewhere.

However, if you need this information more often, and if the number of
values that changes in between is small compared to the total size of
the matrices, you could make a gain in subsequent calculations by
remembering part results. Depending on the situation you could for
example keep the dictionary with the counts and update it each time,
or keep such a dictionary for each "big" matrix, and set a flag when
that dictionary is not up-to-date any more

.

-- 
Andr? Engels, andreengels at gmail.com


From Lacrima.Maxim at gmail.com  Sat Jul  4 04:12:10 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Sat, 4 Jul 2009 01:12:10 -0700 (PDT)
Subject: urllib with x509 certs
Message-ID: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>

Hello!

I am trying to use urllib to fetch some internet resources, using my
client x509 certificate.
I have divided my .p12 file into mykey.key and mycert.cer files.
Then I use following approach:
>>> import urllib
>>> url = 'https://example.com'
>>> xml = '''<request>
... <somexml>somexml</somexml>
</request>'''
>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
>>> f = opener.open(url, xml)

This works Ok! But every time I am asked to enter PEM pass phrase,
which I specified during dividing my .p12 file.
So my question... What should I do to make my code fetch any url
automatically (without asking me every time to enter pass phrase)?
As I understand there is impossible to specify pass phrase while
constructing URLopener.
So what should I do?

With regards, Max
(sorry if my English isn't very proper)


From __peter__ at web.de  Sat Jul  4 04:21:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 04 Jul 2009 10:21:13 +0200
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
Message-ID: <h2n3d8$kvq$00$1@news.t-online.com>

Icarus wrote:

> I'm working on a serial protocol analyzer in python.  We have an
> application written by someone else in MFC but we need something that
> is cross platform.  I intended to implement the GUI portion in Tkinter
> but am having trouble.
> 
> The idea is that I will read messages from the serial port and output
> them to a Tkinter Text object initially.  Eventually it will have
> other functionality but that's it for the short term.  I've written
> this little test app to experiment with putting things on the GUI via
> a Queue which is polled by the Tkinter loop.
> 
> On some machines this code works fine and I get whatever I type in
> displayed in the Text widget.  On others I get errors like this as
> soon as I start it running.
> 
> error in background error handler:
> out of stack space (infinite loop?)
>     while executing
> "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
>     while execu..."
> 
> 
> I don't understand why on some machines it works exactly as expected
> and on others it acts the same way Tkinter does when I call functions
> directly from outside the Tkinter thread.  Does anyone have any
> suggestions?  The full code as appended below.  Thanks in advance.
> 
> [code]
> 
> import Queue
> 
> class functionQueue:
> 
>     def __init__(self, root = None, timeout = 250):
> 
>         self.functionQueue = Queue.Queue()
>         self.root = root
>         self.timeout = timeout
> 
>         if(self.root):
>             self.pop_function(root)
> 
> 
>     def pop_function(self, root = None):
> 
>         try:
>             funcArgList = self.functionQueue.get(block = False)
>         except Queue.Empty:
>             pass
>         else:
>             try:
>                 funcArgList[0](*funcArgList[1])
>             except:
>                 try:
>                     print "Failed to call function", funcArgList[0]
>                 except:
>                     print "Failed to call function"
> 
>         if(root):
>             root.after(self.timeout, lambda: self.pop_function
> (self.root))
> 
>     def add_function(self, function, argList):
> 
>         try:
>             self.functionQueue.put([function, argList])
>         except:
>             pass
> 
> 
> if( __name__ == '__main__'):
> 
>     import Tkinter
>     import thread
> 
>     text = Tkinter.Text()
>     text.pack()
> 
>     myQueue = functionQueue(text, 50)
> 
>     def gui_loop():
>         try:
>             text.mainloop()
>         except:
>             import os
>             os._exit(1)
> 
>     thread.start_new_thread(text.mainloop, ())
> 
>     while(True):
>         usrInput = raw_input()
> 
>         if(usrInput == "-1"):
>             import os
>             os._exit(0)
> 
>         myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>         myQueue.add_function(text.see, ['end'])
> 
> [/code]

I can make it work over here by putting the UI into the main thread, as 
suggested by http://effbot.org/zone/tkinter-threads.htm:

import Queue
import Tkinter
import threading

class FunctionQueue:
    # unchanged

def input_loop():
    while True:
        try:
            usrInput = raw_input()
        except EOFError:
            break
        myQueue.add_function(text.insert, ['end', usrInput + "\n"])
        myQueue.add_function(text.see, ['end'])
    myQueue.add_function(text.quit, [])

if __name__ == '__main__':
    text = Tkinter.Text()
    text.pack()

    myQueue = FunctionQueue(text, 50)
    threading.Thread(target=input_loop).start()
    text.mainloop()

Peter




From clp2 at rebertia.com  Sat Jul  4 04:24:36 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 01:24:36 -0700
Subject: urllib with x509 certs
In-Reply-To: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
Message-ID: <50697b2c0907040124j4e309c25j77e01c8127711f80@mail.gmail.com>

On Sat, Jul 4, 2009 at 1:12 AM, Lacrima<Lacrima.Maxim at gmail.com> wrote:
> Hello!
>
> I am trying to use urllib to fetch some internet resources, using my
> client x509 certificate.
> I have divided my .p12 file into mykey.key and mycert.cer files.
> Then I use following approach:
>>>> import urllib
>>>> url = 'https://example.com'
>>>> xml = '''<request>
> ... <somexml>somexml</somexml>
> </request>'''
>>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
>>>> f = opener.open(url, xml)
>
> This works Ok! But every time I am asked to enter PEM pass phrase,
> which I specified during dividing my .p12 file.
> So my question... What should I do to make my code fetch any url
> automatically (without asking me every time to enter pass phrase)?
> As I understand there is impossible to specify pass phrase while
> constructing URLopener.
> So what should I do?

Subclass FancyURLopener
[http://docs.python.org/library/urllib.html#urllib.FancyURLopener],
overriding the prompt_user_passwd() method
[http://docs.python.org/library/urllib.html#urllib.FancyURLopener.prompt_user_passwd].
Then use an instance of your subclass instead of URLopener.

Cheers,
Chris
-- 
http://blog.rebertia.com


From patrick.just4fun at gmail.com  Sat Jul  4 04:33:03 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Sat, 04 Jul 2009 10:33:03 +0200
Subject: Reversible Debugging
In-Reply-To: <b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
Message-ID: <4A4F13BF.9050605@gmail.com>

Horace Blegg schrieb:
> You might consider using a VM with 'save-points'. You run the program 
> (in a debugger/ida/what have you) to a certain point (logical point 
> would be if/ifelse/else statements, etc) and save the VM state. Once 
> you've saved, you continue. If you find the path you've taken isn't 
> what you are after, you can reload a previous save point and start 
> over, trying a different path the next time.
That was my idea to implement it. I thought of taking snapshots of the 
current state every time a "unredoable instruction", e.g random number 
generation, is done.  For every other instruction I count the number of 
instructions done since the last snapshot. So I can go back one 
instruction by restoring to the previous state and go the number of 
instructions minus one forward.

> This is also somewhat useful if you're trying to debug an error that 
> happens deep inside of a program, so you can continually jump to the 
> point right before the error happens, instead of needing to run 
> through the entire program each time it crashes. Just beware of tunnel 
> vision.
I think of implementing some snapshot/restore mechanism first. That may 
help in many other situations.


From stef.mientki at gmail.com  Sat Jul  4 05:25:38 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sat, 04 Jul 2009 11:25:38 +0200
Subject: Reversible Debugging
In-Reply-To: <4A4E4B8B.7090104@gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
Message-ID: <4A4F2012.2020206@gmail.com>

Patrick Sabin wrote:
> Hello,
>
> I am interested if there are any python modules, that supports 
> reversible debugging aka stepping backwards. Any links or ideas would 
> be helpful, because I am thinking of implementing something like that.
>
In some cases it would be nice to have something like that,
specially in combination with a "normal" debugger,
which allows you to change values on the flight,
like winpdb.

cheers,
Stef
> Thanks in advance,
> Patrick



From martin at v.loewis.de  Sat Jul  4 05:38:15 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sat, 04 Jul 2009 11:38:15 +0200
Subject: urllib with x509 certs
In-Reply-To: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
Message-ID: <4a4f2307$0$8384$9b622d9e@news.freenet.de>

> This works Ok! But every time I am asked to enter PEM pass phrase,
> which I specified during dividing my .p12 file.
> So my question... What should I do to make my code fetch any url
> automatically (without asking me every time to enter pass phrase)?
> As I understand there is impossible to specify pass phrase while
> constructing URLopener.
> So what should I do?

You can remove the passphrase on the private key, e.g. with the
openssl rsa utility.

Regards,
Martin


From banibrata.dutta at gmail.com  Sat Jul  4 05:47:18 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Sat, 4 Jul 2009 15:17:18 +0530
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <h2lvta$3f9$1@ger.gmane.org>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
Message-ID: <3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>

QuoteGoke Aruna <pyklass at gmail.com>

what am saying is reading the ITU info on USSD, is it possible to use python

to write the application SS7 with support for TCAP/MAP talking to E1
card to do the ss7 signalling.

As Chris mentioned "possible, but probably not easy". AFAIK, not much of
what you might need exists in form of existing Python modules, if that's
what you were thinking -- and especially in the Open-source form. The only
open-source initiative in the SS7 domain that I am aware of, is the openss7
(http://www.openss7.org/), which has 'some' software available. No personal
experience though, API's are C/C++ AFAIR, and last I'd checked, the status
wasn't 'practically usable' in functionality terms. If they offer
functionality of the ITU-T SS7 stack upto the TCAP layer, exposing a C/C++
API to create dialogs, create components, populate and send them etc. (usual
TCAP Primitives), then as Chris mentions, you could have Python wrappers
(ctypes, swig...). Then, for the MAP layer, which is largely ASN.1 BER
encoding/decoding, you'd need such functionality in Python. There are some
ASN.1 BER codec implementations having Python API/bindings, but AFAIK, they
are largely domain/application specific (s.a. for SNMP), and not generic or
robust enough. Given the API's however, writing any application s.a. for
performing some "business-logic" on receiving or before sending USSD / SMS
message in Python, that's a no-brainer ! :-)
If however, you want to implement the whole SS7 stack in Python --
everything that Chris wrote is accurate, and that's potentially (and the
most obvious) way you'd have to implement it.

-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/8b1e6c9c/attachment.html>

From clp2 at rebertia.com  Sat Jul  4 05:50:18 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 02:50:18 -0700
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
	<3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
Message-ID: <50697b2c0907040250o8e6d9baqc1b368c2d0c547ff@mail.gmail.com>

On Sat, Jul 4, 2009 at 2:47 AM, Banibrata
Dutta<banibrata.dutta at gmail.com> wrote:
> QuoteGoke Aruna <pyklass at gmail.com>
>>
>> what am saying is reading the ITU info on USSD, is it possible to use
>> python
>>
>> to write the application SS7 with support for TCAP/MAP talking to E1 card
>> to do the ss7 signalling.
>
> As Chris mentioned "possible, but probably not easy". AFAIK, not much of

s/Chris/Dennis/

Credit where credit is due. I merely gave a PyPI link.

Cheers,
Chris
-- 
http://blog.rebertia.com


From banibrata.dutta at gmail.com  Sat Jul  4 05:53:19 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Sat, 4 Jul 2009 15:23:19 +0530
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
	<3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
Message-ID: <3de8e1f70907040253r60211297o8dbea679d3f5273a@mail.gmail.com>

BTW, if you just want to be able to send/receive SMS's in a Python
application, there are several alternatives.
1. Most operators, or 3rd party bulk-SMS vendors (who resell SMS capacity
from operators at a premium but in smaller bundles than what an operator
would sell), offer --
  a. HTTP based mechanism to send/receive messages
  b. SMPP protocol. OpenSMPP has a C API, and you could create Python
wrappers for same.

2. For very low volume application, you could use the Serial (or Serial
emulation over USB/Bluetooth) way, i.e. using "AT" commandset of a tethered
GSM mobile (with inbuilt GSM modem), or a separate GSM-modem (PCMCIA,
USB,...) via Python, to send / receive SMS's.

On Sat, Jul 4, 2009 at 3:17 PM, Banibrata Dutta
<banibrata.dutta at gmail.com>wrote:

> QuoteGoke Aruna <pyklass at gmail.com>
>
> what am saying is reading the ITU info on USSD, is it possible to use python
>
> to write the application SS7 with support for TCAP/MAP talking to E1 card to do the ss7 signalling.
>
> As Chris mentioned "possible, but probably not easy". AFAIK, not much of
> what you might need exists in form of existing Python modules, if that's
> what you were thinking -- and especially in the Open-source form. The only
> open-source initiative in the SS7 domain that I am aware of, is the openss7
> (http://www.openss7.org/), which has 'some' software available. No
> personal experience though, API's are C/C++ AFAIR, and last I'd checked, the
> status wasn't 'practically usable' in functionality terms. If they offer
> functionality of the ITU-T SS7 stack upto the TCAP layer, exposing a C/C++
> API to create dialogs, create components, populate and send them etc. (usual
> TCAP Primitives), then as Chris mentions, you could have Python wrappers
> (ctypes, swig...). Then, for the MAP layer, which is largely ASN.1 BER
> encoding/decoding, you'd need such functionality in Python. There are some
> ASN.1 BER codec implementations having Python API/bindings, but AFAIK, they
> are largely domain/application specific (s.a. for SNMP), and not generic or
> robust enough. Given the API's however, writing any application s.a. for
> performing some "business-logic" on receiving or before sending USSD / SMS
> message in Python, that's a no-brainer ! :-)
> If however, you want to implement the whole SS7 stack in Python --
> everything that Chris wrote is accurate, and that's potentially (and the
> most obvious) way you'd have to implement it.
>
> --
> regards,
> Banibrata
> http://www.linkedin.com/in/bdutta
>



-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/9ad1cd32/attachment.html>

From banibrata.dutta at gmail.com  Sat Jul  4 05:54:08 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Sat, 4 Jul 2009 15:24:08 +0530
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <50697b2c0907040250o8e6d9baqc1b368c2d0c547ff@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
	<3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
	<50697b2c0907040250o8e6d9baqc1b368c2d0c547ff@mail.gmail.com>
Message-ID: <3de8e1f70907040254ucc68ff3l65e791b0457678aa@mail.gmail.com>

On Sat, Jul 4, 2009 at 3:20 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Sat, Jul 4, 2009 at 2:47 AM, Banibrata
> Dutta<banibrata.dutta at gmail.com> wrote:
> > QuoteGoke Aruna <pyklass at gmail.com>
> >>
> >> what am saying is reading the ITU info on USSD, is it possible to use
> >> python
> >>
> >> to write the application SS7 with support for TCAP/MAP talking to E1
> card
> >> to do the ss7 signalling.
> >
> > As Chris mentioned "possible, but probably not easy". AFAIK, not much of
>
> s/Chris/Dennis/
>
> Credit where credit is due. I merely gave a PyPI link.
>

Indeed. Thanks Chris, sorry Dennis.

-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/07f515b4/attachment.html>

From vilya.harvey at gmail.com  Sat Jul  4 05:55:44 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sat, 4 Jul 2009 10:55:44 +0100
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
Message-ID: <6aef848f0907040255y296c5ea1n2fff44c859cf12ab@mail.gmail.com>

2009/7/4 Andre Engels <andreengels at gmail.com>:
> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>> Currently I need to find the most common elements in thousands of
>> arrays within one large array (arround 2 million instances with ~70k
>> unique elements)
>>
>> so I set up a dictionary to handle the counting so when I am
>> iterating ?I up the count on the corrosponding dictionary element. I
>> then iterate through the dictionary and find the 25 most common
>> elements.
>>
>> the elements are initially held in a array within an array. so I am am
>> just trying to find the most common elements between all the arrays
>> contained in one large array.
>> my current code looks something like this:
>> d = {}
>> for arr in my_array:
>> -----for i in arr:
>> #elements are numpy integers and thus are not accepted as dictionary
>> keys
>> -----------d[int(i)]=d.get(int(i),0)+1
>>
>> then I filter things down. but with my algorithm that only takes about
>> 1 sec so I dont need to show it here since that isnt the problem.
>>
>>
>> But there has to be something better. I have to do this many many
>> times and it seems silly to iterate through 2 million things just to
>> get 25. The element IDs are integers and are currently being held in
>> numpy arrays in a larger array. this ID is what makes up the key to
>> the dictionary.
>>
>> ?It currently takes about 5 seconds to accomplish this with my current
>> algorithm.
>>
>> So does anyone know the best solution or algorithm? I think the trick
>> lies in matrix intersections but I do not know.
>
> There's no better algorithm for the general case. No method of
> checking the matrices using less than 2000000-x look-ups will ensure
> you that there's not a new value with x occurences lurking somewhere.

Try flattening the arrays into a single large array & sorting it. Then
you can just iterate over the large array counting as you go; you only
ever have to insert into the dict once for each value and there's no
lookups in the dict. I don't know numpy, so there's probably a more
efficient way to write this, but this should show what I'm talking
about:

big_arr = sorted(reduce(list.__add__, my_array, []))
counts = {}
last_val = big_arr[0]
count = 0
for val in big_arr:
    if val == last_val:
        count += 1
    else:
        counts[last_val] = count
        count = 0
        last_val = val
counts[last_val] = count    # to get the count for the last value.

If flattening the arrays isn't practical, you may still get some
improvements by sorting them individually and applying the same
principle to each of them:

counts = {}
for arr in my_array:
    sorted_arr = sorted(arr)
    last_val = sorted_arr[0]
    count = 0
    for val in sorted_arr:
        if val == last_val:
            count += 1
        else:
            counts[last_val] = counts.get(last_val, 0) + count
            count = 0
            last_val = val
    counts[last_val] = counts.get(last_val, 0) + count

Hope that helps...

Vil.


From parikshatdubey at gmail.com  Sat Jul  4 06:06:11 2009
From: parikshatdubey at gmail.com (Parikshat Dubey)
Date: Sat, 4 Jul 2009 15:36:11 +0530
Subject: Calling C or C++ Functions inside Python script
Message-ID: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>

Hi,

Is this possible to call C functions(inbuilt or user defined) inside python
script.If yes, please illustrate how it can be done.
 Thanks,
Parikshat Dubey
-- 
-----Fear not the path of truth, for the lack of people walking on it.


----Practice yourself, for heaven's sake, in little things; and thence
proceed to
greater.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/ef503323/attachment.html>

From Lacrima.Maxim at gmail.com  Sat Jul  4 06:08:40 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Sat, 4 Jul 2009 03:08:40 -0700 (PDT)
Subject: urllib with x509 certs
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<mailman.2595.1246695878.8015.python-list@python.org>
Message-ID: <df337b53-9194-4ace-bc45-e2b5fbc7c641@b9g2000yqm.googlegroups.com>

On Jul 4, 11:24?am, Chris Rebert <c... at rebertia.com> wrote:
> On Sat, Jul 4, 2009 at 1:12 AM, Lacrima<Lacrima.Ma... at gmail.com> wrote:
> > Hello!
>
> > I am trying to use urllib to fetch some internet resources, using my
> > client x509 certificate.
> > I have divided my .p12 file into mykey.key and mycert.cer files.
> > Then I use following approach:
> >>>> import urllib
> >>>> url = 'https://example.com'
> >>>> xml = '''<request>
> > ... <somexml>somexml</somexml>
> > </request>'''
> >>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
> >>>> f = opener.open(url, xml)
>
> > This works Ok! But every time I am asked to enter PEM pass phrase,
> > which I specified during dividing my .p12 file.
> > So my question... What should I do to make my code fetch any url
> > automatically (without asking me every time to enter pass phrase)?
> > As I understand there is impossible to specify pass phrase while
> > constructing URLopener.
> > So what should I do?
>
> Subclass FancyURLopener
> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener],
> overriding the prompt_user_passwd() method
> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener.prom...].
> Then use an instance of your subclass instead of URLopener.
>
> Cheers,
> Chris
> --http://blog.rebertia.com

Hi Chris,
Thanks for your quick reply.
According to docs the return value of prompt_user_passwd() method
should be a tuple (user, password), but there is no user when
authenticating with certificate. So how should I use this method? This
doesn't work:
>>> import urllib
>>> class MyOpener(urllib.FancyURLopener):
...      def prompt_user_passwd(self, host, realm):
...          return ('password')
...


With regards, Max


From Lacrima.Maxim at gmail.com  Sat Jul  4 06:14:17 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Sat, 4 Jul 2009 03:14:17 -0700 (PDT)
Subject: urllib with x509 certs
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<4a4f2307$0$8384$9b622d9e@news.freenet.de>
Message-ID: <a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>

On Jul 4, 12:38?pm, "Martin v. L?wis" <mar... at v.loewis.de> wrote:
> > This works Ok! But every time I am asked to enter PEM pass phrase,
> > which I specified during dividing my .p12 file.
> > So my question... What should I do to make my code fetch any url
> > automatically (without asking me every time to enter pass phrase)?
> > As I understand there is impossible to specify pass phrase while
> > constructing URLopener.
> > So what should I do?
>
> You can remove the passphrase on the private key, e.g. with the
> openssl rsa utility.
>
> Regards,
> Martin

Hi Martin!

Thanks for the reply. I want my key to be as secure as possible. So I
will remove pass phrase if only there is no other possibility to go
through authentication.

With regards, Max


From clp2 at rebertia.com  Sat Jul  4 06:27:46 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 03:27:46 -0700
Subject: urllib with x509 certs
In-Reply-To: <df337b53-9194-4ace-bc45-e2b5fbc7c641@b9g2000yqm.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<mailman.2595.1246695878.8015.python-list@python.org>
	<df337b53-9194-4ace-bc45-e2b5fbc7c641@b9g2000yqm.googlegroups.com>
Message-ID: <50697b2c0907040327w23b7f0eal13934bc8d33c7231@mail.gmail.com>

2009/7/4 Lacrima <Lacrima.Maxim at gmail.com>:
> On Jul 4, 11:24?am, Chris Rebert <c... at rebertia.com> wrote:
>> On Sat, Jul 4, 2009 at 1:12 AM, Lacrima<Lacrima.Ma... at gmail.com> wrote:
>> > Hello!
>>
>> > I am trying to use urllib to fetch some internet resources, using my
>> > client x509 certificate.
>> > I have divided my .p12 file into mykey.key and mycert.cer files.
>> > Then I use following approach:
>> >>>> import urllib
>> >>>> url = 'https://example.com'
>> >>>> xml = '''<request>
>> > ... <somexml>somexml</somexml>
>> > </request>'''
>> >>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
>> >>>> f = opener.open(url, xml)
>>
>> > This works Ok! But every time I am asked to enter PEM pass phrase,
>> > which I specified during dividing my .p12 file.
>> > So my question... What should I do to make my code fetch any url
>> > automatically (without asking me every time to enter pass phrase)?
>> > As I understand there is impossible to specify pass phrase while
>> > constructing URLopener.
>> > So what should I do?
>>
>> Subclass FancyURLopener
>> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener],
>> overriding the prompt_user_passwd() method
>> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener.prom...].
>> Then use an instance of your subclass instead of URLopener.
>>
>> Cheers,
>> Chris
>> --http://blog.rebertia.com
>
> Hi Chris,
> Thanks for your quick reply.
> According to docs the return value of prompt_user_passwd() method
> should be a tuple (user, password), but there is no user when
> authenticating with certificate. So how should I use this method? This
> doesn't work:
>>>> import urllib
>>>> class MyOpener(urllib.FancyURLopener):
> ... ? ? ?def prompt_user_passwd(self, host, realm):
> ... ? ? ? ? ?return ('password')

Only a guess:

def prompt_user_passwd(self, host, realm):
    return ('', 'password')

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Sat Jul  4 06:29:30 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 03:29:30 -0700
Subject: Calling C or C++ Functions inside Python script
In-Reply-To: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
References: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
Message-ID: <50697b2c0907040329w5085b9c9xa8d6a2aaae9667de@mail.gmail.com>

On Sat, Jul 4, 2009 at 3:06 AM, Parikshat Dubey<parikshatdubey at gmail.com> wrote:
> Hi,
>
> Is this possible to call C functions(inbuilt or user defined) inside python
> script.If yes, please illustrate how it can be done.

The `ctypes` module:
http://docs.python.org/library/ctypes.html
Note: does not work w/ C++ directly.

Cheers,
Chris
-- 
http://blog.rebertia.com


From martin at v.loewis.de  Sat Jul  4 07:09:51 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sat, 04 Jul 2009 13:09:51 +0200
Subject: urllib with x509 certs
In-Reply-To: <a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<4a4f2307$0$8384$9b622d9e@news.freenet.de>
	<a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>
Message-ID: <4A4F387F.7050804@v.loewis.de>

> Thanks for the reply. I want my key to be as secure as possible. So I
> will remove pass phrase if only there is no other possibility to go
> through authentication.

And you put the passphrase into the source code instead? How does it
make that more secure?

Regards,
Martin


From larudwer at freenet.de  Sat Jul  4 08:26:27 2009
From: larudwer at freenet.de (larudwer)
Date: Sat, 4 Jul 2009 14:26:27 +0200
Subject: psyco V2 beta2  benchmark
Message-ID: <h2nhhs$g5m$00$1@news.t-online.com>

just out of curiosity i've downloaded the latest Version of Psyco V2 Beta 2 
and run the benchmarks against the old Version of psyco 1.6

Because it might be of common interest, i am posting the results here.

My machine is a Pentium D 3.2 Ghz running Windows XP SP 3 and Python 2.6.2.
Psyco V2 was built with 4.3.3-tdm-1 mingw32 with optimisation flags changed 
to -O3


Benchmark                                 | avg. Base time | psyco 1.6 time 
| psyco 2.0 time | ratio     | possible error +-
time_anyall all_bool_genexp               | 2.270          | 2.250 
| 2.420          | 0.930     | 8.3 %
time_anyall all_bool_listcomp             | 3.450          | 1.900 
| 1.910          | 0.995     | 0.0 %
time_anyall all_genexp                    | 1.970          | 1.940 
| 2.160          | 0.898     | 9.6 %
time_anyall all_listcomp                  | 3.485          | 1.660 
| 1.660          | 1.000     | 1.4 %
time_anyall all_loop                      | 0.665          | 0.090 
| 0.090          | 1.000     | 4.4 %
time_anyall any_bool_genexp               | 2.215          | 2.130 
| 2.340          | 0.910     | 10.0 %
time_anyall any_bool_listcomp             | 3.620          | 1.930 
| 1.940          | 0.995     | 9.0 %
time_anyall any_genexp                    | 1.985          | 1.920 
| 2.180          | 0.881     | 10.1 %
time_anyall any_listcomp                  | 3.360          | 1.680 
| 1.680          | 1.000     | 8.0 %
time_anyall any_loop                      | 0.660          | 0.090 
| 0.090          | 1.000     | 3.0 %
time_builtins chr(i)                      | 2.420          | 0.010 
| 0.010          | 1.000     | 0.0 %
time_builtins hash(i)                     | 1.280          | 0.370 
| 0.080          | 4.625     | 8.1 %
time_builtins int(round(f))               | 2.635          | 1.510 
| 1.120          | 1.348     | 0.4 %
time_builtins min                         | 0.535          | 0.520 
| 0.120          | 4.333     | 1.9 %
time_builtins min_kw                      | 4.430          | 4.400 
| 0.160          | 27.500    | 0.5 %
time_builtins ord(i)                      | 0.320          | 0.000 
| 0.000          | 1.000     | 6.5 %
time_builtins pow                         | 0.345          | 0.230 
| 0.150          | 1.533     | 2.9 %
time_builtins reduce                      | 0.735          | 0.710 
| 0.020          | 35.498    | 1.4 %
time_builtins round(f)                    | 1.720          | 0.890 
| 0.400          | 2.225     | 1.2 %
time_builtins sums                        | 0.180          | 0.180 
| 0.100          | 1.800     | 0.0 %
time_fib matrix                           | 0.425          | 0.360 
| 0.360          | 1.000     | 2.3 %
time_fib recursive                        | 0.000          | 0.000 
| 0.000          | 1.000     | 0.0 %
time_fib takahashi                        | 0.410          | 0.320 
| 0.330          | 0.970     | 0.0 %
time_generators call next just many times | 0.900          | 0.630 
| 0.970          | 0.649     | 4.3 %
time_generators iterate just many times   | 0.660          | 0.550 
| 0.950          | 0.579     | 3.1 %
time_generators send and loop 1000        | 2.805          | 2.540 
| 0.060          | 42.333    | 9.8 %
time_generators send call loop 1000       | 2.505          | 2.940 
| 0.060          | 48.999    | 10.9 %
time_generators send just many times      | 1.280          | 0.590 
| 0.980          | 0.602     | 3.1 %
time_iter iter                            | 1.490          | 0.590 
| 0.440          | 1.341     | 5.5 %
time_math floats                          | 2.910          | 1.500 
| 1.630          | 0.920     | 0.7 %
time_properties method_get                | 0.935          | 0.120 
| 0.130          | 0.923     | 1.1 %
time_properties method_set                | 1.005          | 0.170 
| 0.180          | 0.944     | 1.0 %
time_properties property_get              | 0.960          | 0.740 
| 0.100          | 7.400     | 2.1 %
time_properties property_set              | 1.020          | 0.920 
| 0.930          | 0.989     | 0.0 %
time_properties pyproperty_get            | 1.535          | 1.310 
| 0.140          | 9.357     | 0.7 %
time_properties pyproperty_set            | 1.030          | 0.920 
| 0.930          | 0.989     | 2.0 %
time_subdist subdist(i)                   | 3.665          | 1.640 
| 6.140          | 0.267     | 0.8 %
time_sums rounding                        | 0.800          | 0.790 
| 0.810          | 0.975     | 2.5 %


Running new timings with 
C:\Programme\GNU\python26\lib\site-packages\psyco\_psyco.pyd Sat Jul 04 
12:09:07 2009

time_anyall    : all_bool_genexp                plain:   2.36     psyco: 
2.42     ratio:  0.97
time_anyall    : all_bool_listcomp              plain:   3.45     psyco: 
1.91     ratio:  1.80
time_anyall    : all_genexp                     plain:   2.06     psyco: 
2.16     ratio:  0.95
time_anyall    : all_listcomp                   plain:   3.51     psyco: 
1.66     ratio:  2.11
time_anyall    : all_loop                       plain:   0.65     psyco: 
0.09     ratio:  7.03
time_anyall    : any_bool_genexp                plain:   2.32     psyco: 
2.34     ratio:  0.99
time_anyall    : any_bool_listcomp              plain:   3.45     psyco: 
1.94     ratio:  1.78
time_anyall    : any_genexp                     plain:   2.08     psyco: 
2.18     ratio:  0.96
time_anyall    : any_listcomp                   plain:   3.49     psyco: 
1.68     ratio:  2.08
time_anyall    : any_loop                       plain:   0.65     psyco: 
0.09     ratio:  7.05
time_builtins  : chr(i)                         plain:   2.42     psyco: 
0.01     ratio: 197.40
time_builtins  : hash(i)                        plain:   1.33     psyco: 
0.08     ratio: 17.69
time_builtins  : int(round(f))                  plain:   2.63     psyco: 
1.12     ratio:  2.36
time_builtins  : min                            plain:   0.53     psyco: 
0.12     ratio:  4.28
time_builtins  : min_kw                         plain:   4.44     psyco: 
0.16     ratio: 28.58
time_builtins  : ord(i)                         plain:   0.33     psyco: 
0.00     ratio: 123.57
time_builtins  : pow                            plain:   0.34     psyco: 
0.15     ratio:  2.24
time_builtins  : reduce                         plain:   0.74     psyco: 
0.02     ratio: 40.93
time_builtins  : round(f)                       plain:   1.73     psyco: 
0.40     ratio:  4.38
time_builtins  : sums                           plain:   0.18     psyco: 
0.10     ratio:  1.80
time_fib       : matrix                         plain:   0.42     psyco: 
0.36     ratio:  1.18
time_fib       : recursive                      plain:   0.00     psyco: 
0.00     ratio: 19.45
time_fib       : takahashi                      plain:   0.41     psyco: 
0.33     ratio:  1.25
time_generators: send call loop 1000            plain:   2.36     psyco: 
0.06     ratio: 41.30
time_generators: send and loop 1000             plain:   2.66     psyco: 
0.06     ratio: 46.69
time_generators: send just many times           plain:   1.26     psyco: 
0.98     ratio:  1.29
time_generators: iterate just many times        plain:   0.67     psyco: 
0.95     ratio:  0.70
time_generators: call next just many times      plain:   0.88     psyco: 
0.97     ratio:  0.91
time_iter      : iter                           plain:   1.53     psyco: 
0.44     ratio:  3.47
time_math      : floats                         plain:   2.90     psyco: 
1.63     ratio:  1.78
time_properties: method_get                     plain:   0.93     psyco: 
0.13     ratio:  7.22
time_properties: method_set                     plain:   1.00     psyco: 
0.18     ratio:  5.61
time_properties: property_get                   plain:   0.95     psyco: 
0.10     ratio:  9.26
time_properties: property_set                   plain:   1.02     psyco: 
0.93     ratio:  1.09
time_properties: pyproperty_get                 plain:   1.54     psyco: 
0.14     ratio: 10.80
time_properties: pyproperty_set                 plain:   1.04     psyco: 
0.93     ratio:  1.12
time_subdist   : subdist(i)                     plain:   3.68     psyco: 
6.14     ratio:  0.60
time_sums      : rounding                       plain:   0.79     psyco: 
0.81     ratio:  0.98


Running new timings with original psyco

time_anyall    : all_bool_genexp                plain:   2.18     psyco: 
2.25     ratio:  0.97
time_anyall    : all_bool_listcomp              plain:   3.45     psyco: 
1.90     ratio:  1.82
time_anyall    : all_genexp                     plain:   1.88     psyco: 
1.94     ratio:  0.97
time_anyall    : all_listcomp                   plain:   3.46     psyco: 
1.66     ratio:  2.09
time_anyall    : all_loop                       plain:   0.68     psyco: 
0.09     ratio:  7.34
time_anyall    : any_bool_genexp                plain:   2.11     psyco: 
2.13     ratio:  0.99
time_anyall    : any_bool_listcomp              plain:   3.79     psyco: 
1.93     ratio:  1.96
time_anyall    : any_genexp                     plain:   1.89     psyco: 
1.92     ratio:  0.98
time_anyall    : any_listcomp                   plain:   3.23     psyco: 
1.68     ratio:  1.92
time_anyall    : any_loop                       plain:   0.67     psyco: 
0.09     ratio:  7.26
time_builtins  : chr(i)                         plain:   2.42     psyco: 
0.01     ratio: 197.10
time_builtins  : hash(i)                        plain:   1.23     psyco: 
0.37     ratio:  3.30
time_builtins  : int(round(f))                  plain:   2.64     psyco: 
1.51     ratio:  1.75
time_builtins  : min                            plain:   0.54     psyco: 
0.52     ratio:  1.03
time_builtins  : min_kw                         plain:   4.42     psyco: 
4.40     ratio:  1.00
time_builtins  : ord(i)                         plain:   0.31     psyco: 
0.00     ratio: 116.56
time_builtins  : pow                            plain:   0.35     psyco: 
0.23     ratio:  1.50
time_builtins  : reduce                         plain:   0.73     psyco: 
0.71     ratio:  1.03
time_builtins  : round(f)                       plain:   1.71     psyco: 
0.89     ratio:  1.91
time_builtins  : sums                           plain:   0.18     psyco: 
0.18     ratio:  1.03
time_fib       : matrix                         plain:   0.43     psyco: 
0.36     ratio:  1.19
time_fib       : recursive                      plain:   0.00     psyco: 
0.00     ratio: 19.28
time_fib       : takahashi                      plain:   0.41     psyco: 
0.32     ratio:  1.27
time_generators: send call loop 1000            plain:   2.65     psyco: 
2.94     ratio:  0.90
time_generators: send and loop 1000             plain:   2.95     psyco: 
2.54     ratio:  1.16
time_generators: send just many times           plain:   1.30     psyco: 
0.59     ratio:  2.23
time_generators: iterate just many times        plain:   0.65     psyco: 
0.55     ratio:  1.17
time_generators: call next just many times      plain:   0.92     psyco: 
0.63     ratio:  1.45
time_iter      : iter                           plain:   1.45     psyco: 
0.59     ratio:  2.47
time_math      : floats                         plain:   2.92     psyco: 
1.50     ratio:  1.95
time_properties: method_get                     plain:   0.94     psyco: 
0.12     ratio:  7.88
time_properties: method_set                     plain:   1.01     psyco: 
0.17     ratio:  6.08
time_properties: property_get                   plain:   0.97     psyco: 
0.74     ratio:  1.31
time_properties: property_set                   plain:   1.02     psyco: 
0.92     ratio:  1.12
time_properties: pyproperty_get                 plain:   1.53     psyco: 
1.31     ratio:  1.17
time_properties: pyproperty_set                 plain:   1.02     psyco: 
0.92     ratio:  1.11
time_subdist   : subdist(i)                     plain:   3.65     psyco: 
1.64     ratio:  2.23
time_sums      : rounding                       plain:   0.81     psyco: 
0.79     ratio:  1.03





From Scott.Daniels at Acm.Org  Sat Jul  4 08:28:01 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 05:28:01 -0700
Subject: question of style
In-Reply-To: <687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
Message-ID: <rcCdnXfdkOC51NLXnZ2dnUVZ_s-dnZ2d@pdx.net>

upwestdon wrote:
> if not (self.higher and self.lower):
>     return self.higher or self.lower

     self.lower = 0
     self.higher = 123
     ???
More than just None is False


From Scott.Daniels at Acm.Org  Sat Jul  4 08:31:55 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 05:31:55 -0700
Subject: Reversible Debugging
In-Reply-To: <mailman.2596.1246696386.8015.python-list@python.org>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
	<mailman.2596.1246696386.8015.python-list@python.org>
Message-ID: <rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>

Patrick Sabin wrote:
> Horace Blegg schrieb:
>> You might consider using a VM with 'save-points'. You run the program 
>> (in a debugger/ida/what have you) to a certain point (logical point 
>> would be if/ifelse/else statements, etc) and save the VM state. Once 
>> you've saved, you continue. If you find the path you've taken isn't 
>> what you are after, you can reload a previous save point and start 
>> over, trying a different path the next time.
> That was my idea to implement it. I thought of taking snapshots of the 
> current state every time a "unredoable instruction", e.g random number 
> generation, is done. 
Remember, storing into a location is destruction.
Go over a list of VM instructions and see how many of them are undoable.


From tn.pablo at gmail.com  Sat Jul  4 09:25:39 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sat, 4 Jul 2009 08:25:39 -0500
Subject: Calling C or C++ Functions inside Python script
In-Reply-To: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
References: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
Message-ID: <fdd00b510907040625s67a58c42ndb03d7c014457dac@mail.gmail.com>

On Sat, Jul 4, 2009 at 05:06, Parikshat Dubey<parikshatdubey at gmail.com> wrote:
> Hi,
>
> Is this possible to call C functions(inbuilt or user defined) inside python
> script.If yes, please illustrate how it can be done.
> Thanks,
> Parikshat Dubey

>From http://www.swig.org  :

"SWIG is a software development tool that connects programs written in C
and C++ with a variety of high-level programming languages. SWIG is used
with different types of languages including common scripting languages
such as Perl, PHP, Python, Tcl and Ruby. "


---
Pablo Torres N.


From http  Sat Jul  4 09:29:09 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 06:29:09 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<h2mmt2$48p$1@panix3.panix.com>
Message-ID: <7xws6oa862.fsf@ruckus.brouhaha.com>

aahz at pythoncraft.com (Aahz) writes:
> AFAICT, in order for Maybe and Option to work, you need to have some
> kind of static typing system.  Am I missing something?

I'm not sure.  Maybe there could be some kind of syntactic support in
a dynamic language (not that I'm suggesting adding that to Python).
I've been meaning to look up how Erlang does it.  For the limited
purpose of regexps that might or might not match, Perl has some
special support.

A kludgy Python counterpart to Option might be to use a pair (present, x)
where present is a bool saying whether the value is available.  If
present is True, then x is the value.  That could make it harder to
forget to test the flag before using the value.

In the stuff I'm doing, I often find it best to just use a list value,
so instead of:

     y = f(x) if x is not None else None

I can just write

     y = map(f, x)

In many cases it later turns out that list really was the natural
representation and it ends up growing additional potential elements.
I saw some article about database design recently that claimed as a
program evolves, all relationships end up becoming many-to-many.  It
gave as an example, if your program deals with names and addresses, it
will eventually have to handle the case where someone has more than
one residence address.


From davea at ieee.org  Sat Jul  4 09:31:44 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 09:31:44 -0400
Subject: question of style
In-Reply-To: <687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
Message-ID: <4A4F59C0.8030201@ieee.org>

upwestdon wrote:
> On Jul 2, 1:23 pm, Simon Forman <sajmik... at gmail.com> wrote:
>   
>> Hey I was hoping to get your opinions on a sort of minor stylistic
>> point.
>> These two snippets of code are functionally identical. Which would you
>> use and why?
>> The first one is easier [for me anyway] to read and understand, but
>> slightly less efficient, while the second is [marginally] harder to
>> follow but more efficient.
>>
>> ## First snippet
>>
>> if self.higher is self.lower is None: return
>> if self.lower is None: return self.higher
>> if self.higher is None: return self.lower
>>
>> ## Second snippet
>>
>> if self.higher is None:
>>     if self.lower is None:
>>         return
>>     return self.lower
>> if self.lower is None:
>>     return self.higher
>>
>> What do you think?
>>
>> (One minor point: in the first snippet, the "is None" in the first
>> line is superfluous in the context in which it will be used, the only
>> time "self.lower is self.higher" will be true is when they are both
>> None.)
>>     
>
> How about just:
>
> if not (self.higher and self.lower):
>     return self.higher or self.lower
>
>   
But if self.higher is 0  and self.lower is None, this'll return None, 
which wasn't the original intent.

Without having some documented constraints on the self.higher and lower 
types and values, it's difficult to simplify further.



From neilcrighton at gmail.com  Sat Jul  4 09:39:41 2009
From: neilcrighton at gmail.com (Neil Crighton)
Date: Sat, 4 Jul 2009 13:39:41 +0000 (UTC)
Subject: finding most common elements between thousands of multiple arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <loom.20090704T132837-496@post.gmane.org>

You can join all your arrays into a single big array with concatenate.

>>> import numpy as np
>>> a = np.concatenate(array_of_arrays)

Then count the number of occurrances of each unique element using this trick
with searchsorted. This should be pretty fast.

>>> a.sort()
>>> unique_a = np.unique(a)
>>> count = []
>>> for val in unique_a:
...     count.append(a.searchsorted(val,side='right') - a.searchsorted(val,
side='left'))
>>> mostcommonvals = unique_a[np.argsort(count)[-25:]]


Neil



From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 09:42:06 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 13:42:06 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
Message-ID: <025f4dbf$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:

> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>> Currently I need to find the most common elements in thousands of
>>> arrays within one large array (arround 2 million instances with ~70k
>>> unique elements)
...
>> There's no better algorithm for the general case. No method of checking
>> the matrices using less than 2000000-x look-ups will ensure you that
>> there's not a new value with x occurences lurking somewhere.
> 
> Try flattening the arrays into a single large array & sorting it. Then
> you can just iterate over the large array counting as you go; you only
> ever have to insert into the dict once for each value and there's no
> lookups in the dict.

You're suggesting to do a whole bunch of work copying 2,000,000 pointers 
into a single array, then a whole bunch of more work sorting that second 
array (which is O(N*log N) on average), and then finally iterate over the 
second array. Sure, that last step will on average involve fewer than 
O(N) steps, but to get to that point you've already done more work than 
just iterating over the array-of-arrays in the first place.

Now, if you're really lucky, your strategy can be done in fast C code 
instead of slow Python code, and you might see a speed-up for values of N 
which aren't too big. But I wouldn't put money on it.

Another strategy might be to pre-count elements in each array, as you 
build or modify them. This will marginally slow down each modification 
you make to the array, but the payback will be that finding the frequency 
of any element will be almost instantaneous.


-- 
Steven


From davea at ieee.org  Sat Jul  4 09:58:39 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 09:58:39 -0400
Subject: Reversible Debugging
In-Reply-To: <rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>
	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
Message-ID: <4A4F600F.8040402@ieee.org>



Scott David Daniels wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Patrick 
> Sabin wrote:
>> Horace Blegg schrieb:
>>> You might consider using a VM with 'save-points'. You run the 
>>> program (in a debugger/ida/what have you) to a certain point 
>>> (logical point would be if/ifelse/else statements, etc) and save the 
>>> VM state. Once you've saved, you continue. If you find the path 
>>> you've taken isn't what you are after, you can reload a previous 
>>> save point and start over, trying a different path the next time.
>> That was my idea to implement it. I thought of taking snapshots of 
>> the current state every time a "unredoable instruction", e.g random 
>> number generation, is done. 
> Remember, storing into a location is destruction.
> Go over a list of VM instructions and see how many of them are undoable.
>
> </div>
>
>
Read his suggested approach more carefully.  He's not "undoing" 
anything.  He's rolling back to the save-point, and then stepping 
forward to the desired spot.  Except for influences outside his control 
(eg. file system operations), this approach has to work.  Even random 
will work the same, if the generator uses only data that was restored 
from the save-point.  A typical pseudo-random generator works from a 
seed, and if the seed is restored as part of rolling back, he's fine.  
If the snapshot is done via VMWare (for example), he's even okay for 
file operations, except for network and VM-shared files.

"I thought of taking snapshots of the current state every time a 
"unredoable instruction", e.g random number generation, is done.  For 
every other instruction I count the number of instructions done since 
the last snapshot. So I can go back one instruction by restoring to the 
previous state and go the number of instructions minus one forward."

DaveA



From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 10:10:01 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 14:10:01 GMT
Subject: Reversible Debugging
References: <4A4E4B8B.7090104@gmail.com>
	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
	<mailman.2596.1246696386.8015.python-list@python.org>
	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
	<mailman.2610.1246715935.8015.python-list@python.org>
Message-ID: <025f544a$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 09:58:39 -0400, Dave Angel wrote:

> Read his suggested approach more carefully.  He's not "undoing"
> anything.  He's rolling back to the save-point, and then stepping
> forward to the desired spot.  Except for influences outside his control
> (eg. file system operations), this approach has to work.

Is that anything like saying "Except for all the diseases this drug won't 
cure, it cures everything"?

*wink*


-- 
Steven


From Scott.Daniels at Acm.Org  Sat Jul  4 10:19:48 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 07:19:48 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <mailman.2602.1246701345.8015.python-list@python.org>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
Message-ID: <5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>

Vilya Harvey wrote:
> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>> Currently I need to find the most common elements in thousands of
>>> arrays within one large array (arround 2 million instances with ~70k
>>> unique elements)...
> Try flattening the arrays into a single large array & sorting it. Then
> you can just iterate over the large array counting as you go; you only
> ever have to insert into the dict once for each value and there's no
> lookups in the dict....

Actually the next step is to maintain a min-heap as you run down the
sorted array.  Something like:

import numpy as np
import heapq


def frequency(arr):
     '''Generate frequency-value pairs from a numpy array'''
     clustered = arr.flatten() # copy (so can safely sort)
     clustered.sort() # Bring identical values together
     scanner = iter(clustered)
     last = scanner.next()
     count = 1
     for el in scanner:
         if el == last:
             count += 1
         else:
             yield count, last
             last = el
             count = 1
     yield count, last


def most_frequent(arr, N):
     '''Return the top N (freq, val) elements in arr'''
     counted = frequency(arr) # get an iterator for freq-val pairs
     heap = []
     # First, just fill up the array with the first N distinct
     for i in range(N):
         try:
             heap.append(counted.next())
         except StopIteration:
             break # If we run out here, no need for a heap
     else:
         # more to go, switch to a min-heap, and replace the least
         # element every time we find something better
         heapq.heapify(heap)
         for pair in counted:
             if pair > heap[0]:
                 heapq.heapreplace(heap, pair)
     return sorted(heap, reverse=True) # put most frequent first.


--Scott David Daniels
Scott.Daniels at Acm.Org


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 10:38:52 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 14:38:52 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <025f5b0d$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 13:42:06 +0000, Steven D'Aprano wrote:

> On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:
> 
>> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>>> Currently I need to find the most common elements in thousands of
>>>> arrays within one large array (arround 2 million instances with ~70k
>>>> unique elements)
> ...
>>> There's no better algorithm for the general case. No method of
>>> checking the matrices using less than 2000000-x look-ups will ensure
>>> you that there's not a new value with x occurences lurking somewhere.
>> 
>> Try flattening the arrays into a single large array & sorting it. Then
>> you can just iterate over the large array counting as you go; you only
>> ever have to insert into the dict once for each value and there's no
>> lookups in the dict.
> 
> You're suggesting to do a whole bunch of work copying 2,000,000 pointers
> into a single array, then a whole bunch of more work sorting that second
> array (which is O(N*log N) on average), and then finally iterate over
> the second array. Sure, that last step will on average involve fewer
> than O(N) steps, 

Er what?

Ignore that last comment -- I don't know what I was thinking. You still 
have to iterate over all N elements, sorted or not.

> but to get to that point you've already done more work
> than just iterating over the array-of-arrays in the first place.

What it does buy you though, as you pointed out, is reducing the number 
of explicit dict lookups and writes. However, dict lookups and writes are 
very fast, fast enough that they're used throughout Python. A line like:

count += 1

actually is a dict lookup and write.



-- 
Steven


From sajmikins at gmail.com  Sat Jul  4 10:54:38 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sat, 4 Jul 2009 07:54:38 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
Message-ID: <069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>

On Jul 4, 2:03?am, upwestdon <upwest... at gmail.com> wrote:
> On Jul 2, 1:23?pm, Simon Forman <sajmik... at gmail.com> wrote:
>
>
>
> > Hey I was hoping to get your opinions on a sort of minor stylistic
> > point.
> > These two snippets of code are functionally identical. Which would you
> > use and why?
> > The first one is easier [for me anyway] to read and understand, but
> > slightly less efficient, while the second is [marginally] harder to
> > follow but more efficient.
>
> > ## First snippet
>
> > if self.higher is self.lower is None: return
> > if self.lower is None: return self.higher
> > if self.higher is None: return self.lower
>
> > ## Second snippet
>
> > if self.higher is None:
> > ? ? if self.lower is None:
> > ? ? ? ? return
> > ? ? return self.lower
> > if self.lower is None:
> > ? ? return self.higher
>
> > What do you think?
>
> > (One minor point: in the first snippet, the "is None" in the first
> > line is superfluous in the context in which it will be used, the only
> > time "self.lower is self.higher" will be true is when they are both
> > None.)
>
> How about just:
>
> if not (self.higher and self.lower):
> ? ? return self.higher or self.lower

That would work too in this case, both higher and lower are expected
to be either None or an object (that doesn't override the default all-
objects-are-true rule.)

Thanks,
~Simon


From no.email at please.post  Sat Jul  4 11:00:00 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 15:00:00 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
Message-ID: <h2nqpf$d91$1@reader1.panix.com>

In <7xk52p4tgg.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

>kj <no.email at please.post> writes:
>>     sense = cmp(func(hi), func(lo))
>>     if sense == 0:
>>         return None
>>     target_plus = sense * target + epsilon
>>     target_minus = sense * target - epsilon
>>     ...

>The code looks confusing to me and in some sense incorrect.  Suppose
>func(hi)==func(lo)==target.

In hindsight, I too think that it is incorrect, but for a different
reason.  I've rewritten it like this:

    sense = cmp(func(hi), func(lo))
    assert sense != 0, "func is not strictly monotonic in [lo, hi]"

I regard the very special case of func(hi)==func(lo)==target as
pathological (analogous to the fact that a stopped watch is "exactly
right" twice a day), and not one I care to support.

Thanks for your feedback!

kj


From Scott.Daniels at Acm.Org  Sat Jul  4 11:03:39 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 08:03:39 -0700
Subject: Reversible Debugging
In-Reply-To: <mailman.2610.1246715935.8015.python-list@python.org>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
	<mailman.2610.1246715935.8015.python-list@python.org>
Message-ID: <AJ6dnQT3dIoC8NLXnZ2dnUVZ_radnZ2d@pdx.net>

Dave Angel wrote:
> Scott David Daniels wrote:
>> Patrick Sabin wrote:
>>> Horace Blegg schrieb:
>>>> You might consider using a VM with 'save-points'. You run the 
>>>> program (in a debugger/ida/what have you) to a certain point 
>>>> (logical point would be if/ifelse/else statements, etc) and save the 
>>>> VM state. Once you've saved, you continue. If you find the path 
>>>> you've taken isn't what you are after, you can reload a previous 
>>>> save point and start over, trying a different path the next time.
>>> That was my idea to implement it. I thought of taking snapshots of 
>>> the current state every time a "unredoable instruction", e.g random 
>>> number generation, is done. 
>> Remember, storing into a location is destruction.
>> Go over a list of VM instructions and see how many of them are undoable.
> Read his suggested approach more carefully.  He's not "undoing" 
> anything.  He's rolling back to the save-point, and then stepping 
> forward to the desired spot.  
Right, I did misread "unredoable" as "undoable."  However, I suspect a
surprising amount of stuff is "unredoable" -- iff the random number
generator counts as one of those things.  The random number seeder is
unredoable with empty args, but running the generator once seeded is
predictable (by design).  If you don't capture the random number state
as part of your "snapshot," _lots_ of C space storage will be in the
same class, and you are stuck finding the exceptional "safe to use"
cases, rather than the exceptional "unsafe to use."  Similarly, system
calls about time or _any_ callback (when and where executed) create
snapshot points, and I suspect roll forwards will be relatively short.
In fact, in some sense the _lack_ of a callback is unredoable.

--Scott David Daniels
Scott.Daniels at Acm.Org


From no.email at please.post  Sat Jul  4 11:05:48 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 15:05:48 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
Message-ID: <h2nr4c$d91$2@reader1.panix.com>

In <zxr3m.613$P5.65 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:

>> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:
>>> 1. Don't use assertions to test argument values!


>On 7/3/2009 12:19 PM kj apparently wrote:
>> Out of curiosity, where does this come from? 


>http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_stmt
>"The current code generator emits no code for an assert statement when optimization is requested at compile time."

Sorry, this doesn't say anything like "don't use assertions to test
argument values".  I'm aware of the fact that assertions are silenced
under certain circumstances.  But where does the principle 1. in
your first reply come from?  I've never seen it before, and would
like to understand the reasoning behind it.

kj


From vinay_sajip at yahoo.co.uk  Sat Jul  4 11:12:36 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Sat, 4 Jul 2009 08:12:36 -0700 (PDT)
Subject: ANN: A new version of the Python module which wraps GnuPG has been 
	released.
Message-ID: <mailman.2635.1246798963.8015.python-announce-list@python.org>

A new version of the Python module which wraps GnuPG has been
released.

What Does It Do?
================
The gnupg module allows Python programs to make use of the
functionality provided by the Gnu Privacy Guard (abbreviated GPG or
GnuPG). Using this module, Python programs can encrypt and decrypt
data, digitally sign documents and verify digital signatures, manage
(generate, list and delete) encryption keys, using proven Public Key
Infrastructure (PKI) encryption technology based on OpenPGP.

This module is expected to be used with Python versions >= 2.4, as it
makes use of the subprocess module which appeared in that version of
Python. Development and testing has been carried out on Windows and
Ubuntu. This module is a newer version derived from earlier work by
Andrew Kuchling, Richard Jones and Steve Traugott.

A test suite using unittest is included with the source distribution.

Simple usage:

>>> import gnupg
>>> gpg = gnupg.GPG(gnupghome='/path/to/keyring/directory')
>>> gpg.list_keys()
[{
  ...
  'fingerprint': 'F819EE7705497D73E3CCEE65197D5DAC68F1AAB2',
  'keyid': '197D5DAC68F1AAB2',
  'length': '1024',
  'type': 'pub',
  'uids': ['', 'Gary Gross (A test user) <gary.gross at gamma.com>']},
 {
  ...
  'fingerprint': '37F24DD4B918CC264D4F31D60C5FEFA7A921FC4A',
  'keyid': '0C5FEFA7A921FC4A',
  'length': '1024',
  ...
  'uids': ['', 'Danny Davis (A test user) <danny.davis at delta.com>']}]
>>> encrypted = gpg.encrypt("Hello, world!", ['0C5FEFA7A921FC4A'])
>>> str(encrypted)
'-----BEGIN PGP MESSAGE-----\nVersion: GnuPG v1.4.9 (GNU/Linux)\n
\nhQIOA/6NHMDTXUwcEAf
...
-----END PGP MESSAGE-----\n'
>>> decrypted = gpg.decrypt(str(encrypted), passphrase='secret')
>>> str(decrypted)
'Hello, world!'
>>> signed = gpg.sign("Goodbye, world!", passphrase='secret')
>>> verified = verified = gpg.verify(str(signed))
>>> print "Verified" if verified else "Not verified"
'Verified'

For more information, visit http://code.google.com/p/python-gnupg/ -
as always, your feedback is most welcome (especially bug reports,
patches and suggestions for improvement). Enjoy!

Cheers

Vinay Sajip
Red Dove Consultants Ltd.


From asm198 at gmail.com  Sat Jul  4 11:23:33 2009
From: asm198 at gmail.com (Icarus)
Date: Sat, 4 Jul 2009 08:23:33 -0700 (PDT)
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
	<h2n3d8$kvq$00$1@news.t-online.com>
Message-ID: <c46b4e76-2c0d-49b5-bb97-c7e38934ac46@y7g2000yqa.googlegroups.com>

On Jul 4, 3:21?am, Peter Otten <__pete... at web.de> wrote:
> Icarus wrote:
> > I'm working on a serial protocol analyzer in python. ?We have an
> > application written by someone else in MFC but we need something that
> > is cross platform. ?I intended to implement the GUI portion in Tkinter
> > but am having trouble.
>
> > The idea is that I will read messages from the serial port and output
> > them to a Tkinter Text object initially. ?Eventually it will have
> > other functionality but that's it for the short term. ?I've written
> > this little test app to experiment with putting things on the GUI via
> > a Queue which is polled by the Tkinter loop.
>
> > On some machines this code works fine and I get whatever I type in
> > displayed in the Text widget. ?On others I get errors like this as
> > soon as I start it running.
>
> > error in background error handler:
> > out of stack space (infinite loop?)
> > ? ? while executing
> > "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> > 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
> > ? ? while execu..."
>
> > I don't understand why on some machines it works exactly as expected
> > and on others it acts the same way Tkinter does when I call functions
> > directly from outside the Tkinter thread. ?Does anyone have any
> > suggestions? ?The full code as appended below. ?Thanks in advance.
>
> > [code]
>
> > import Queue
>
> > class functionQueue:
>
> > ? ? def __init__(self, root = None, timeout = 250):
>
> > ? ? ? ? self.functionQueue = Queue.Queue()
> > ? ? ? ? self.root = root
> > ? ? ? ? self.timeout = timeout
>
> > ? ? ? ? if(self.root):
> > ? ? ? ? ? ? self.pop_function(root)
>
> > ? ? def pop_function(self, root = None):
>
> > ? ? ? ? try:
> > ? ? ? ? ? ? funcArgList = self.functionQueue.get(block = False)
> > ? ? ? ? except Queue.Empty:
> > ? ? ? ? ? ? pass
> > ? ? ? ? else:
> > ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? funcArgList[0](*funcArgList[1])
> > ? ? ? ? ? ? except:
> > ? ? ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? ? ? print "Failed to call function", funcArgList[0]
> > ? ? ? ? ? ? ? ? except:
> > ? ? ? ? ? ? ? ? ? ? print "Failed to call function"
>
> > ? ? ? ? if(root):
> > ? ? ? ? ? ? root.after(self.timeout, lambda: self.pop_function
> > (self.root))
>
> > ? ? def add_function(self, function, argList):
>
> > ? ? ? ? try:
> > ? ? ? ? ? ? self.functionQueue.put([function, argList])
> > ? ? ? ? except:
> > ? ? ? ? ? ? pass
>
> > if( __name__ == '__main__'):
>
> > ? ? import Tkinter
> > ? ? import thread
>
> > ? ? text = Tkinter.Text()
> > ? ? text.pack()
>
> > ? ? myQueue = functionQueue(text, 50)
>
> > ? ? def gui_loop():
> > ? ? ? ? try:
> > ? ? ? ? ? ? text.mainloop()
> > ? ? ? ? except:
> > ? ? ? ? ? ? import os
> > ? ? ? ? ? ? os._exit(1)
>
> > ? ? thread.start_new_thread(text.mainloop, ())
>
> > ? ? while(True):
> > ? ? ? ? usrInput = raw_input()
>
> > ? ? ? ? if(usrInput == "-1"):
> > ? ? ? ? ? ? import os
> > ? ? ? ? ? ? os._exit(0)
>
> > ? ? ? ? myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> > ? ? ? ? myQueue.add_function(text.see, ['end'])
>
> > [/code]
>
> I can make it work over here by putting the UI into the main thread, as
> suggested byhttp://effbot.org/zone/tkinter-threads.htm:
>
> import Queue
> import Tkinter
> import threading
>
> class FunctionQueue:
> ? ? # unchanged
>
> def input_loop():
> ? ? while True:
> ? ? ? ? try:
> ? ? ? ? ? ? usrInput = raw_input()
> ? ? ? ? except EOFError:
> ? ? ? ? ? ? break
> ? ? ? ? myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> ? ? ? ? myQueue.add_function(text.see, ['end'])
> ? ? myQueue.add_function(text.quit, [])
>
> if __name__ == '__main__':
> ? ? text = Tkinter.Text()
> ? ? text.pack()
>
> ? ? myQueue = FunctionQueue(text, 50)
> ? ? threading.Thread(target=input_loop).start()
> ? ? text.mainloop()
>
> Peter

Peter, thanks for the suggestion.  I tried your code exactly on my box
and I still get the same results.  As soon as I run the script and
every time I click on the Text box I get tcl::Bgerror ... just like I
mentioned above.  I'm fairly certain that I'm not calling Tkinter
functions from any other thread but it's acting as though I am as soon
as I create the input thread.
If I comment out the input loop thread everything is fine but of
course that's not terribly useful as a logging box.


From tn.pablo at gmail.com  Sat Jul  4 11:26:15 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sat, 4 Jul 2009 10:26:15 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2nr4c$d91$2@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
Message-ID: <fdd00b510907040826k18cd4ffena72a6c9ce7601a48@mail.gmail.com>

On Sat, Jul 4, 2009 at 10:05, kj<no.email at please.post> wrote:
>>http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_stmt
>>"The current code generator emits no code for an assert statement when optimization is requested at compile time."
>
> Sorry, this doesn't say anything like "don't use assertions to test
> argument values". ?I'm aware of the fact that assertions are silenced
> under certain circumstances. ?But where does the principle 1. in
> your first reply come from? ?I've never seen it before, and would
> like to understand the reasoning behind it.
>
> kj
> --
> http://mail.python.org/mailman/listinfo/python-list
>

But...if no code is generated for assertions on some occasions, then the
parameters would go unchecked, potentially breaking your code in said
occasions.

-- 
Pablo Torres N.


From aahz at pythoncraft.com  Sat Jul  4 11:48:21 2009
From: aahz at pythoncraft.com (Aahz)
Date: 4 Jul 2009 08:48:21 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<h2mmt2$48p$1@panix3.panix.com>
	<7xws6oa862.fsf@ruckus.brouhaha.com>
Message-ID: <h2ntk5$rgh$1@panix3.panix.com>

In article <7xws6oa862.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>
>In many cases it later turns out that list really was the natural
>representation and it ends up growing additional potential elements.
>I saw some article about database design recently that claimed as a
>program evolves, all relationships end up becoming many-to-many.  It
>gave as an example, if your program deals with names and addresses, it
>will eventually have to handle the case where someone has more than
>one residence address.

That's definitely a critical point, and I absolutely agree that this
should get rubbed into people's faces.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From dw at botanicus.net  Sat Jul  4 11:50:56 2009
From: dw at botanicus.net (David Wilson)
Date: Sat, 4 Jul 2009 08:50:56 -0700 (PDT)
Subject: Where does setuptools live?
Message-ID: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>

I'm trying to create a patch for a diabolical issue I keep running
into, but I can't seem to find the setuptools repository. Is it this
one?

    http://svn.python.org/view/sandbox/trunk/setuptools/

It's seen no changes in 9 months.

The issue in question is its (ab)use of .svn to directly read working
copy information rather than going via the well designed 'svn info --
xml' route, which if done, wouldn't result in setuptools busting every
few years, nor require me to downgrade my Subversion installation (OS
X packages don't support multiple versions installed at a time),
checkout a source tree, use setuptools, then re-upgrade so I can go
back to using my other trees.


David


From davea at ieee.org  Sat Jul  4 12:09:34 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 12:09:34 -0400
Subject: Reversible Debugging
In-Reply-To: <025f544a$0$20657$c3e8da3@news.astraweb.com>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>	<mailman.2610.1246715935.8015.python-list@python.org>
	<025f544a$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <4A4F7EBE.4030004@ieee.org>



Steven D'Aprano wrote:
> On Sat, 04 Jul 2009 09:58:39 -0400, Dave Angel wrote:
>
>   
>> Read his suggested approach more carefully.  He's not "undoing"
>> anything.  He's rolling back to the save-point, and then stepping
>> forward to the desired spot.  Except for influences outside his control
>> (eg. file system operations), this approach has to work.
>>     
>
> Is that anything like saying "Except for all the diseases this drug won't 
> cure, it cures everything"?
>
> *wink*
>
>
>   
<grin>
Yeah, pretty close.  That's the problem with speaking in concepts, 
rather than something concrete.

Somebody else brought up VM, but that has two meanings these days.  The 
sense I took it (with regard to save-point) was a program like VMWare, 
where it virtualizes the entire machine.  So any program that deals only 
with the local machine will fit that approach.  And yes, I know there 
are subtleties beyond networks and virtual networks, like time.  When 
you roll the VM back, the time magically stays current.  But for a 
program that deals only with its own process, that tends to just look 
like some other process suddenly hogged the CPU.

Now, if the snapshot is a feature of the Python VM, that's another 
matter entirely.



From amrita at iisermohali.ac.in  Sat Jul  4 12:21:12 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 4 Jul 2009 21:51:12 +0530 (IST)
Subject: mail
Message-ID: <22154.210.212.36.65.1246724472.squirrel@www.iisermohali.ac.in>

Hi,

I want to know that whether using python programming is it possible to
extract chemical shift information about some amino acids of some protein
from BMRB(BioMagResBank) or Ref-DB(referenced databank) or not.

Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From hanooter at gmail.com  Sat Jul  4 12:22:48 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 09:22:48 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com> 
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>

OK then. I will try some of the strategies here but I guess things
arent looking too good. I need to run this over a dataset that someone
pickled. I need to run this 480,000 times so you can see my
frustration. So it doesn't need to be "real time" but it would be nice
it was done sorting this month.

Is there a "bet guess" strategy where it is not 100% accurate but much
faster?

On Jul 4, 7:38?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Sat, 04 Jul 2009 13:42:06 +0000, Steven D'Aprano wrote:
> > On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:
>
> >> 2009/7/4 Andre Engels <andreeng... at gmail.com>:
> >>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanoo... at gmail.com> wrote:
> >>>> Currently I need to find the most common elements in thousands of
> >>>> arrays within one large array (arround 2 million instances with ~70k
> >>>> unique elements)
> > ...
> >>> There's no better algorithm for the general case. No method of
> >>> checking the matrices using less than 2000000-x look-ups will ensure
> >>> you that there's not a new value with x occurences lurking somewhere.
>
> >> Try flattening the arrays into a single large array & sorting it. Then
> >> you can just iterate over the large array counting as you go; you only
> >> ever have to insert into the dict once for each value and there's no
> >> lookups in the dict.
>
> > You're suggesting to do a whole bunch of work copying 2,000,000 pointers
> > into a single array, then a whole bunch of more work sorting that second
> > array (which is O(N*log N) on average), and then finally iterate over
> > the second array. Sure, that last step will on average involve fewer
> > than O(N) steps,
>
> Er what?
>
> Ignore that last comment -- I don't know what I was thinking. You still
> have to iterate over all N elements, sorted or not.
>
> > but to get to that point you've already done more work
> > than just iterating over the array-of-arrays in the first place.
>
> What it does buy you though, as you pointed out, is reducing the number
> of explicit dict lookups and writes. However, dict lookups and writes are
> very fast, fast enough that they're used throughout Python. A line like:
>
> count += 1
>
> actually is a dict lookup and write.
>
> --
> Steven



From __peter__ at web.de  Sat Jul  4 12:24:06 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 04 Jul 2009 18:24:06 +0200
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
	<h2n3d8$kvq$00$1@news.t-online.com>
	<c46b4e76-2c0d-49b5-bb97-c7e38934ac46@y7g2000yqa.googlegroups.com>
Message-ID: <h2nvmi$9oh$03$1@news.t-online.com>

Icarus wrote:

> On Jul 4, 3:21 am, Peter Otten <__pete... at web.de> wrote:
>> Icarus wrote:
>> > I'm working on a serial protocol analyzer in python.  We have an
>> > application written by someone else in MFC but we need something that
>> > is cross platform.  I intended to implement the GUI portion in Tkinter
>> > but am having trouble.
>>
>> > The idea is that I will read messages from the serial port and output
>> > them to a Tkinter Text object initially.  Eventually it will have
>> > other functionality but that's it for the short term.  I've written
>> > this little test app to experiment with putting things on the GUI via
>> > a Queue which is polled by the Tkinter loop.
>>
>> > On some machines this code works fine and I get whatever I type in
>> > displayed in the Text widget.  On others I get errors like this as
>> > soon as I start it running.
>>
>> > error in background error handler:
>> > out of stack space (infinite loop?)
>> > while executing
>> > "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
>> > 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
>> > while execu..."
>>
>> > I don't understand why on some machines it works exactly as expected
>> > and on others it acts the same way Tkinter does when I call functions
>> > directly from outside the Tkinter thread.  Does anyone have any
>> > suggestions?  The full code as appended below.  Thanks in advance.
>>
>> > [code]
>>
>> > import Queue
>>
>> > class functionQueue:
>>
>> > def __init__(self, root = None, timeout = 250):
>>
>> > self.functionQueue = Queue.Queue()
>> > self.root = root
>> > self.timeout = timeout
>>
>> > if(self.root):
>> > self.pop_function(root)
>>
>> > def pop_function(self, root = None):
>>
>> > try:
>> > funcArgList = self.functionQueue.get(block = False)
>> > except Queue.Empty:
>> > pass
>> > else:
>> > try:
>> > funcArgList[0](*funcArgList[1])
>> > except:
>> > try:
>> > print "Failed to call function", funcArgList[0]
>> > except:
>> > print "Failed to call function"
>>
>> > if(root):
>> > root.after(self.timeout, lambda: self.pop_function
>> > (self.root))
>>
>> > def add_function(self, function, argList):
>>
>> > try:
>> > self.functionQueue.put([function, argList])
>> > except:
>> > pass
>>
>> > if( __name__ == '__main__'):
>>
>> > import Tkinter
>> > import thread
>>
>> > text = Tkinter.Text()
>> > text.pack()
>>
>> > myQueue = functionQueue(text, 50)
>>
>> > def gui_loop():
>> > try:
>> > text.mainloop()
>> > except:
>> > import os
>> > os._exit(1)
>>
>> > thread.start_new_thread(text.mainloop, ())
>>
>> > while(True):
>> > usrInput = raw_input()
>>
>> > if(usrInput == "-1"):
>> > import os
>> > os._exit(0)
>>
>> > myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>> > myQueue.add_function(text.see, ['end'])
>>
>> > [/code]
>>
>> I can make it work over here by putting the UI into the main thread, as
>> suggested byhttp://effbot.org/zone/tkinter-threads.htm:
>>
>> import Queue
>> import Tkinter
>> import threading
>>
>> class FunctionQueue:
>> # unchanged
>>
>> def input_loop():
>> while True:
>> try:
>> usrInput = raw_input()
>> except EOFError:
>> break
>> myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>> myQueue.add_function(text.see, ['end'])
>> myQueue.add_function(text.quit, [])
>>
>> if __name__ == '__main__':
>> text = Tkinter.Text()
>> text.pack()
>>
>> myQueue = FunctionQueue(text, 50)
>> threading.Thread(target=input_loop).start()
>> text.mainloop()
>>
>> Peter
> 
> Peter, thanks for the suggestion.  I tried your code exactly on my box
> and I still get the same results.  As soon as I run the script and
> every time I click on the Text box I get tcl::Bgerror ... just like I
> mentioned above.  I'm fairly certain that I'm not calling Tkinter
> functions from any other thread but it's acting as though I am as soon
> as I create the input thread.
> If I comment out the input loop thread everything is fine but of
> course that's not terribly useful as a logging box.

http://bugs.python.org/issue3835

Could tcl have been built without thread support on the failing machines?

Peter



From no.email at please.post  Sat Jul  4 12:30:10 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 16:30:10 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
Message-ID: <h2o02i$3gs$1@reader1.panix.com>

In <mailman.2611.1246721197.8015.python-list at python.org> "Pablo Torres N." <tn.pablo at gmail.com> writes:

>On Sat, Jul 4, 2009 at 10:05, kj<no.email at please.post> wrote:
>>>http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_s=
>tmt
>>>"The current code generator emits no code for an assert statement when op=
>timization is requested at compile time."
>>
>> Sorry, this doesn't say anything like "don't use assertions to test
>> argument values". =C2=A0I'm aware of the fact that assertions are silence=
>d
>> under certain circumstances. =C2=A0But where does the principle 1. in
>> your first reply come from? =C2=A0I've never seen it before, and would
>> like to understand the reasoning behind it.
>>
>> kj
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>

>But...if no code is generated for assertions on some occasions, then the
>parameters would go unchecked, potentially breaking your code in said
>occasions.

This implies that code that uses *any* assert statement (other than
perhaps the trivial and meaningless ones like "assert True") is
liable to break, because whatever it is that these assert statements
are checking "on some occasions, ... would go unchecked, potentially
breaking your code."

I'm beginning to think that the original "precept" was simply "cargo
cult," i.e. one of those rules that are parroted without being
fully understood.

As I wrote in my original post, the function I posted was an internal
("helper") function, not to be used outside of the file.  This fact
was further (ahem) underscored by the leading underscore in the
function's name.  Under these circumstances, the assert statements
seem to me perfectly in keeping with the intended use for them. 

kj



From floris.bruynooghe at gmail.com  Sat Jul  4 12:35:47 2009
From: floris.bruynooghe at gmail.com (Floris Bruynooghe)
Date: Sat, 4 Jul 2009 09:35:47 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
Message-ID: <3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>

On Jul 4, 4:50?pm, David Wilson <d... at botanicus.net> wrote:
> I'm trying to create a patch for a diabolical issue I keep running
> into, but I can't seem to find the setuptools repository. Is it this
> one?
>
> ? ?http://svn.python.org/view/sandbox/trunk/setuptools/

It is, see
http://mail.python.org/pipermail/distutils-sig/2009-July/012374.html


> It's seen no changes in 9 months.

It's setuptools...  I'm sure you can find many flamefests on distutils-
sig about this.


Regards
Floris


From python at mrabarnett.plus.com  Sat Jul  4 12:40:48 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 04 Jul 2009 17:40:48 +0100
Subject: Problems with using queue in Tkinter application
In-Reply-To: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
Message-ID: <4A4F8610.1080202@mrabarnett.plus.com>

Icarus wrote:
> I'm working on a serial protocol analyzer in python.  We have an
> application written by someone else in MFC but we need something that
> is cross platform.  I intended to implement the GUI portion in Tkinter
> but am having trouble.
> 
> The idea is that I will read messages from the serial port and output
> them to a Tkinter Text object initially.  Eventually it will have
> other functionality but that's it for the short term.  I've written
> this little test app to experiment with putting things on the GUI via
> a Queue which is polled by the Tkinter loop.
> 
> On some machines this code works fine and I get whatever I type in
> displayed in the Text widget.  On others I get errors like this as
> soon as I start it running.
> 
> error in background error handler:
> out of stack space (infinite loop?)
>     while executing
> "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
>     while execu..."
> 
> 
> I don't understand why on some machines it works exactly as expected
> and on others it acts the same way Tkinter does when I call functions
> directly from outside the Tkinter thread.  Does anyone have any
> suggestions?  The full code as appended below.  Thanks in advance.
> 
> [code]
> 
> import Queue
> 
> class functionQueue:
> 
>     def __init__(self, root = None, timeout = 250):
> 
>         self.functionQueue = Queue.Queue()
>         self.root = root
>         self.timeout = timeout
> 
>         if(self.root):
>             self.pop_function(root)
> 
> 
>     def pop_function(self, root = None):
> 
>         try:
>             funcArgList = self.functionQueue.get(block = False)
>         except Queue.Empty:
>             pass
>         else:
>             try:
>                 funcArgList[0](*funcArgList[1])
>             except:
>                 try:
>                     print "Failed to call function", funcArgList[0]
>                 except:
>                     print "Failed to call function"
> 
>         if(root):
>             root.after(self.timeout, lambda: self.pop_function
> (self.root))
> 
>     def add_function(self, function, argList):
> 
>         try:
>             self.functionQueue.put([function, argList])
>         except:
>             pass
> 
> 
> if( __name__ == '__main__'):
> 
>     import Tkinter
>     import thread
> 
>     text = Tkinter.Text()
>     text.pack()
> 
>     myQueue = functionQueue(text, 50)
> 
>     def gui_loop():
>         try:
>             text.mainloop()
>         except:
>             import os
>             os._exit(1)
> 
>     thread.start_new_thread(text.mainloop, ())
> 
>     while(True):
>         usrInput = raw_input()
> 
>         if(usrInput == "-1"):
>             import os
>             os._exit(0)
> 
>         myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>         myQueue.add_function(text.see, ['end'])
> 
> [/code]
> 
Only an idea, but:

     myQueue = functionQueue(text, 50)

runs in the main thread, so the pop_function method is calling Tkinter
methods in the main thread every 50ms.

But:

     thread.start_new_thread(text.mainloop, ())

is running the Tkinter main loop in another thread.

You might be experiencing a race condition, so different timings on
different machines might cause a problem to appear sooner on one than
another.


From fabiofz at gmail.com  Sat Jul  4 13:17:31 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Sat, 4 Jul 2009 14:17:31 -0300
Subject: Python debugger
In-Reply-To: <740981.83964.qm@web7901.mail.in.yahoo.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
Message-ID: <cfb578b20907041017r4a9f0c9td8ead460955edea6@mail.gmail.com>

> Hi,
> Could you suggest some python debuggers?
>
> Thanks,
> Srini


Pydev has a debugger that supports the common debugger features
(watches, multiple threads, breakpoints, conditional breakpoints, step
in, out, etc -- http://fabioz.com/pydev/manual_adv_debugger.html ),
and pydev extensions adds to that a remote debugger (
http://fabioz.com/pydev/manual_adv_remote_debugger.html ) and a
console ( http://fabioz.com/pydev/manual_adv_debug_console.html ).

Cheers,

Fabio


From patrick.just4fun at gmail.com  Sat Jul  4 13:21:14 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Sat, 04 Jul 2009 19:21:14 +0200
Subject: Reversible Debugging
In-Reply-To: <4A4F7EBE.4030004@ieee.org>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>	<mailman.2610.1246715935.8015.python-list@python.org>	<025f544a$0$20657$c3e8da3@news.astraweb.com>
	<4A4F7EBE.4030004@ieee.org>
Message-ID: <4A4F8F8A.4080702@gmail.com>


> Now, if the snapshot is a feature of the Python VM, that's another 
> matter entirely.
I thought of taking a snapshot using fork, which creates a copy of the 
process. It may not be the
most performant, but it should be quite portable. Of course there are 
some issues with
multithreading/multiprocessing.

If someone has another idea of taking a snapshot let me know. Using 
VMWare is not a
very elegant way in my opinion.



From nagle at animats.com  Sat Jul  4 13:33:15 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 04 Jul 2009 10:33:15 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
Message-ID: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>

    As an example of code that really needs to run fast, but is
speed-limited by Python's limitations, see "tokenizer.py" in

	http://code.google.com/p/html5lib/

This is a parser for HTML 5, a piece of code that will be needed
in many places and will process large amounts of data. It's written
entirely in Python.  Take a look at how much work has to be performed
per character.

This is a good test for Python implementation bottlenecks.  Run
that tokenizer on HTML, and see where the time goes.

("It should be written in C" is not an acceptable answer.)

Python doesn't have a "switch" or "case" statement, and when
you need a state machine with many states, that makes for painful,
slow code.  There's a comment in the code that it would be useful
to run a few billion lines of HTML through an instrumented version
of the parser to decide in which order the IF statements should be
executed.  You shouldn't have to do that.

Yes, I've read PEP 3103.  The big problem is the difficulty of figuring
out what's a constant and what might change.  If all the cases are constants,
case statements are easy.  But in Python, the compiler can't tell.

Parsers have many named compile-time constants.  Python doesn't support
named compile-time constants, and this is one of the places where we
have to pay the bill for that limitation.

Something to think about when you need three more racks of servers
because the HTML parser is slow.

				John Nagle


From jeremy.cowles at gmail.com  Sat Jul  4 13:44:57 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Sat, 4 Jul 2009 10:44:57 -0700
Subject: Zipped Python?
Message-ID: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>

Hi all,

I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e. no
install). My intentions are to use it for a distributed computing project
(PyMW) where there is no guarantee that Python is installed on the worker
machines and an interactive install is out of the question.

I've been looking around, but I haven't been able to turn anything useful up
so far. Any help would be appreciated.

--
Jeremy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/b04f1041/attachment.html>

From vilya.harvey at gmail.com  Sat Jul  4 13:53:58 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sat, 4 Jul 2009 18:53:58 +0100
Subject: Reversible Debugging
In-Reply-To: <4A4F8F8A.4080702@gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
	<mailman.2596.1246696386.8015.python-list@python.org>
	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
	<mailman.2610.1246715935.8015.python-list@python.org>
	<025f544a$0$20657$c3e8da3@news.astraweb.com>
	<4A4F7EBE.4030004@ieee.org> <4A4F8F8A.4080702@gmail.com>
Message-ID: <6aef848f0907041053j24d646a4rd6eca49e44a4b0d7@mail.gmail.com>

2009/7/4 Patrick Sabin <patrick.just4fun at gmail.com>:
> If someone has another idea of taking a snapshot let me know. Using VMWare
> is not a
> very elegant way in my opinion.

Someone implemented the same idea for Java a while ago. They called it
"omniscient debugging"; you can find details at
    http://www.lambdacs.com/debugger/
and a paper about it at
    http://www.lambdacs.com/debugger/AADEBUG_Mar_03.pdf

Another more recent paper on the topic is
    http://scg.unibe.ch/archive/papers/Lien08bBackInTimeDebugging.pdf

I haven't read either of these papers myself, but maybe they'll give
you some ideas.

Vil.


From vilya.harvey at gmail.com  Sat Jul  4 13:59:24 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sat, 4 Jul 2009 18:59:24 +0100
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <025f5b0d$0$20657$c3e8da3@news.astraweb.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <6aef848f0907041059n27f88449v16d5fdb4af5c22d2@mail.gmail.com>

2009/7/4 Steven D'Aprano <steve at remove-this-cybersource.com.au>:
> On Sat, 04 Jul 2009 13:42:06 +0000, Steven D'Aprano wrote:
>
>> On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:
>>
>>> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>>>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>>>> Currently I need to find the most common elements in thousands of
>>>>> arrays within one large array (arround 2 million instances with ~70k
>>>>> unique elements)
>> ...
>>>> There's no better algorithm for the general case. No method of
>>>> checking the matrices using less than 2000000-x look-ups will ensure
>>>> you that there's not a new value with x occurences lurking somewhere.
>>>
>>> Try flattening the arrays into a single large array & sorting it. Then
>>> you can just iterate over the large array counting as you go; you only
>>> ever have to insert into the dict once for each value and there's no
>>> lookups in the dict.
>>
>> You're suggesting to do a whole bunch of work copying 2,000,000 pointers
>> into a single array, then a whole bunch of more work sorting that second
>> array (which is O(N*log N) on average), and then finally iterate over
>> the second array. Sure, that last step will on average involve fewer
>> than O(N) steps,
>
> Er what?
>
> Ignore that last comment -- I don't know what I was thinking. You still
> have to iterate over all N elements, sorted or not.
>
>> but to get to that point you've already done more work
>> than just iterating over the array-of-arrays in the first place.
>
> What it does buy you though, as you pointed out, is reducing the number
> of explicit dict lookups and writes. However, dict lookups and writes are
> very fast, fast enough that they're used throughout Python. A line like:
>
> count += 1
>
> actually is a dict lookup and write.

I did some tests, just to be sure, and you're absolutely right: just
creating the flattened list took several hundred (!) times as long as
iterating through all the lists in place. Live and learn...

Vil.


From benjamin.kaplan at case.edu  Sat Jul  4 14:03:52 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Sat, 4 Jul 2009 14:03:52 -0400
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <ec96e1390907041103k6f29b21oe3141d2733de3aca@mail.gmail.com>

On Sat, Jul 4, 2009 at 1:33 PM, John Nagle<nagle at animats.com> wrote:
> ? As an example of code that really needs to run fast, but is
> speed-limited by Python's limitations, see "tokenizer.py" in
>
> ? ? ? ?http://code.google.com/p/html5lib/
>
> This is a parser for HTML 5, a piece of code that will be needed
> in many places and will process large amounts of data. It's written
> entirely in Python. ?Take a look at how much work has to be performed
> per character.
>
> This is a good test for Python implementation bottlenecks. ?Run
> that tokenizer on HTML, and see where the time goes.
>
> ("It should be written in C" is not an acceptable answer.)
>
> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code. ?There's a comment in the code that it would be useful
> to run a few billion lines of HTML through an instrumented version
> of the parser to decide in which order the IF statements should be
> executed. ?You shouldn't have to do that.
>

If you're cases are hashable, just use a dict instead of the if chain.
Then you get the constant time access to it.

def func_a() :
   ...
def func_b():
   ...
def func_c():
   ....

case = {"a":func_a, "b":func_b, "c":func_c}

case[value]()

> Yes, I've read PEP 3103. ?The big problem is the difficulty of figuring
> out what's a constant and what might change. ?If all the cases are
> constants,
> case statements are easy. ?But in Python, the compiler can't tell.
>
> Parsers have many named compile-time constants. ?Python doesn't support
> named compile-time constants, and this is one of the places where we
> have to pay the bill for that limitation.
>
> Something to think about when you need three more racks of servers
> because the HTML parser is slow.
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?John Nagle
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From http  Sat Jul  4 14:10:48 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:10:48 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
Message-ID: <7x8wj4uxnb.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> > if not (self.higher and self.lower):
> > ? ? return self.higher or self.lower
> 
> That would work too in this case, both higher and lower are expected
> to be either None or an object (that doesn't override the default all-
> objects-are-true rule.)

-1.

Objects can support methods like __bool__, __len__ (a tree might use
this to compute the number of nodes or something like that), and
__nonzero__.  If len(object)==0 then the object is treated as false.
So that test can fail if a __len__ method gets added to the tree class
sometime.  Or you might decide you want to support empty trees which
would test as false.

Anyway, Python's overloading of bool(...) is yet another misfeature
and although it's convenient, the "explicit is better than implicit"
principle indicates to avoid that sort of trick.  


From mwilson at the-wire.com  Sat Jul  4 14:20:09 2009
From: mwilson at the-wire.com (Mel)
Date: Sat, 04 Jul 2009 14:20:09 -0400
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <h2o5ml$27qv$1@services.telesweet.net>

John Nagle wrote:
[ ... ]
> Parsers have many named compile-time constants.  Python doesn't support
> named compile-time constants, and this is one of the places where we
> have to pay the bill for that limitation.
> 
> Something to think about when you need three more racks of servers
> because the HTML parser is slow.

One technique used in such a case is to dispatch different case-handling 
functions via a dictionary lookup.

	Mel.




From http  Sat Jul  4 14:20:20 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:20:20 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
Message-ID: <7x4otsux7f.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
>     sense = cmp(func(hi), func(lo))
>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"

bisection search usually just requires the function to be continuous
and to have its value cross the target somewhere between the endpoints,
not be monotonic.

> I regard the very special case of func(hi)==func(lo)==target as
> pathological (analogous to the fact that a stopped watch is "exactly
> right" twice a day), and not one I care to support.

I do think you should support that case, under the "do 'nothing'
gracefully" principle.  Having your equation solver crash if the
equation is already solved is like having your sorting function crash
if the input is already sorted.  E.g. the function should do something
reasonable if you end up calling it twice.


From http  Sat Jul  4 14:29:20 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:29:20 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
Message-ID: <7xzlbkti7z.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
> This implies that code that uses *any* assert statement (other than
> perhaps the trivial and meaningless ones like "assert True") is
> liable to break, because whatever it is that these assert statements
> are checking "on some occasions, ... would go unchecked, potentially
> breaking your code."

Yes, that implication is absolutely valid.  The purpose of assert
statements is to debug the code, by checking for conditions that are
supposed to be impossible.  Unless the program is broken (i.e.  the
impossible happened), no assert statement should ever trigger.

Invalid input data is not considered impossible and doesn't imply a
broken program, so assert statements are not the appropriate way to
check for it.  I like to use a function like

  def check(condition, msg="data error"):
     if not condition: raise ValueError, msg

  ... 
  check (x >= 0, "invalid x")  # raises ValueError if x is negative
  y = sqrt(x)

instead.


From lie.1296 at gmail.com  Sat Jul  4 14:36:38 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sat, 04 Jul 2009 18:36:38 GMT
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
Message-ID: <WiN3m.2614$ze1.857@news-server.bigpond.net.au>

mclovin wrote:
> OK then. I will try some of the strategies here but I guess things
> arent looking too good. I need to run this over a dataset that someone
> pickled. I need to run this 480,000 times so you can see my
> frustration. So it doesn't need to be "real time" but it would be nice
> it was done sorting this month.
> 
> Is there a "bet guess" strategy where it is not 100% accurate but much
> faster?

Heuristics?

If you don't need 100% accuraccy, you can simply sample 10000 or so
element and find the most common element in this small sample space. It
should be much faster, though you'll probably need to determine the best
cutoff number (too small and you're risking biases, too large and it
would be slower). random.sample() might be useful here.


From http  Sat Jul  4 14:40:19 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:40:19 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <7xvdm8thpo.fsf@ruckus.brouhaha.com>

John Nagle <nagle at animats.com> writes:
> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code.  ...
> There's a comment in the code that it would be useful
> to run a few billion lines of HTML through an instrumented version
> of the parser to decide in which order the IF statements should be
> executed.  You shouldn't have to do that.

In that particular program it would probably be better to change those
if/elif/elif/else constructs to dictionary lookups.  I see the program
already does that for some large tables.



From python at mrabarnett.plus.com  Sat Jul  4 14:43:24 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 04 Jul 2009 19:43:24 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <7xzlbkti7z.fsf@ruckus.brouhaha.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
Message-ID: <4A4FA2CC.1080105@mrabarnett.plus.com>

Paul Rubin wrote:
> kj <no.email at please.post> writes:
>> This implies that code that uses *any* assert statement (other than
>> perhaps the trivial and meaningless ones like "assert True") is
>> liable to break, because whatever it is that these assert statements
>> are checking "on some occasions, ... would go unchecked, potentially
>> breaking your code."
> 
> Yes, that implication is absolutely valid.  The purpose of assert
> statements is to debug the code, by checking for conditions that are
> supposed to be impossible.  Unless the program is broken (i.e.  the
> impossible happened), no assert statement should ever trigger.
> 
Technically these are known as "invariants". An assertion will always be
True if the program is bug-free, no matter what the user might throw at
it; it's not the same as validation.

> Invalid input data is not considered impossible and doesn't imply a
> broken program, so assert statements are not the appropriate way to
> check for it.  I like to use a function like
> 
>   def check(condition, msg="data error"):
>      if not condition: raise ValueError, msg
> 
>   ... 
>   check (x >= 0, "invalid x")  # raises ValueError if x is negative
>   y = sqrt(x)
> 
> instead.



From alan.isaac at gmail.com  Sat Jul  4 14:54:02 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sat, 04 Jul 2009 18:54:02 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2o02i$3gs$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
Message-ID: <ezN3m.828$P5.11@nwrddc02.gnilink.net>

On 7/4/2009 12:30 PM kj apparently wrote:
> I'm beginning to think that the original "precept" was simply "cargo
> cult," i.e. one of those rules that are parroted without being
> fully understood.


Adopting such a view is of course an alternative to
attempting to understand, but perhaps less useful.

Alan Isaac

PS For additional explanation:
http://java.sun.com/j2se/1.4.2/docs/guide/lang/assert.html


From grante at visi.com  Sat Jul  4 15:15:31 2009
From: grante at visi.com (Grant Edwards)
Date: Sat, 04 Jul 2009 14:15:31 -0500
Subject: mail
References: <mailman.2614.1246725781.8015.python-list@python.org>
Message-ID: <SIGdnTlPq_HON9LXnZ2dnUVZ_tadnZ2d@posted.usinternet>

On 2009-07-04, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:

> I want to know that whether using python programming is it
> possible to extract chemical shift information about some
> amino acids of some protein from BMRB(BioMagResBank) or
> Ref-DB(referenced databank) or not.

Yes.

I don't know how easy it would be, but I'm pretty confident it
is possible.

I'm assuming it is currently possible to do so using some sort
of software.  If it's currently impossible to do so using other
methods (e.g. such information doesn't exist or you don't have
access to the dabases), then using Python isn't going cause any
miracles to happen.

-- 
Grant



From Scott.Daniels at Acm.Org  Sat Jul  4 15:51:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 12:51:58 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
Message-ID: <tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>

mclovin wrote:
> OK then. I will try some of the strategies here but I guess things
> arent looking too good. I need to run this over a dataset that someone
> pickled. I need to run this 480,000 times so you can see my
> frustration. So it doesn't need to be "real time" but it would be nice
> it was done sorting this month.
> 
> Is there a "bet guess" strategy where it is not 100% accurate but much
> faster?

Well, I timed a run of a version of mine, and the scan is approx 5X
longer than the copy-and-sort.  Time arr_of_arr.flatten().sort() to
see how quickly the copy and sort happens.So you could try a variant
exploiting the following property:
     If you know the minimum length of a run that will be in the top 25,
then the value for each of the most-frequent run entries must show up at
positions n * stride and (n + 1) * stride (for some n).  That should
drastically reduce the scan cost, as long as stride is reasonably large.

For my uniformly distributed 0..1024 values in 5M x 5M array,
About 2.5 sec to flatten and sort.
About 15 sec to run one of my heapish thingies.
the least frequency encountered: 24716
so, with stride at

sum(flattened[:-stride:stride] == flattened[stride::stride]) == 1000
So there are only 1000 points to investigate.
With any distribution other than uniform, that should go _way_ down.
So just pull out those points, use bisect to get their frequencies, and 
feed those results into the heap accumulation.

--Scott David Daniels


From Scott.Daniels at Acm.Org  Sat Jul  4 16:01:00 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 13:01:00 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <7xzlbkti7z.fsf@ruckus.brouhaha.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
Message-ID: <zu-dnXX0eefNLtLXnZ2dnUVZ_uWdnZ2d@pdx.net>

Paul Rubin wrote:
> Invalid input data is not considered impossible and doesn't imply a
> broken program, so assert statements are not the appropriate way to
> check for it.  I like to use a function like
> 
>   def check(condition, msg="data error"):
>      if not condition: raise ValueError, msg
> 
>   ... 
>   check (x >= 0, "invalid x")  # raises ValueError if x is negative
>   y = sqrt(x)

And I curse such uses, since I don't get to see the troublesome value,
or why it is troublesome.  In the above case, y = sqrt(x) at least
raises ValueError('math domain error'), which is more information than
you are providing.

How about:

      ...
      if x >= 0: raise ValueError('x = %r not allowed (negative)?' % x)
      ...

--Scott David Daniels
Scott.Daniels at Acm.Org


From sajmikins at gmail.com  Sat Jul  4 16:05:36 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sat, 4 Jul 2009 13:05:36 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com> 
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com> 
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
Message-ID: <0a175b39-f084-4814-92e0-80b6cfce6130@c36g2000yqn.googlegroups.com>

On Jul 4, 2:10?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> writes:
> > > if not (self.higher and self.lower):
> > > ? ? return self.higher or self.lower
>
> > That would work too in this case, both higher and lower are expected
> > to be either None or an object (that doesn't override the default all-
> > objects-are-true rule.)
>
> -1.

Heh heh heh, I figured someone might call me on this, but I stopped
short of adding further elucidation to that parenthetical clause.

What I meant (of course, *wink*) was "...an instance of a user-defined
class that doesn't override the special double-underscore methods in a
way that causes it (the instance) to be considered False in a 'boolean
context', as they say in perl."

In [1]: class bar: pass
   ...:

In [2]: b = bar()

In [3]: bool(b)
Out[3]: True



> Objects can support methods like __bool__, __len__ (a tree might use
> this to compute the number of nodes or something like that), and
> __nonzero__. ?If len(object)==0 then the object is treated as false.
> So that test can fail if a __len__ method gets added to the tree class
> sometime. ?Or you might decide you want to support empty trees which
> would test as false.

Ya, that's exactly why I stuck to checking explicitly against None in
that tree code. :]


> Anyway, Python's overloading of bool(...) is yet another misfeature
> and although it's convenient, the "explicit is better than implicit"
> principle indicates to avoid that sort of trick. ?

I really like the "misfeature" myself.  Python (to me) seems to
relieve you of gory details that get in the way (compare equivalent C+
+ and Python code) but still exposes you to gory details that, with
care in coding, can make your code easier to grok and more elegant in
general.

BTW, Paul, kind of a tangent: I reimplemented the same algorithm but
using tuples instead of instances (and empty tuples for "NULL"
values.)  I was trying to mess around in the space you seemed to
indicate existed, i.e. a better implementation using other datatypes,
but I didn't have a clear idea what I was doing and, as I said, I
started by simply re-implementing with a different datatype.

Much to my surprise and delight, I discovered the tuple-based BTree
was /already/ a "persistent data type"!  It was both awesome and a bit
of an anti-climax. :]


From http  Sat Jul  4 16:55:04 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 13:55:04 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<zu-dnXX0eefNLtLXnZ2dnUVZ_uWdnZ2d@pdx.net>
Message-ID: <7xbpo0f9sn.fsf@ruckus.brouhaha.com>

Scott David Daniels <Scott.Daniels at Acm.Org> writes:
> And I curse such uses, since I don't get to see the troublesome value,
> or why it is troublesome.  In the above case, y = sqrt(x) at least
> raises ValueError('math domain error'), which is more information than
> you are providing.
>
> How about:
>       if x >= 0: raise ValueError('x = %r not allowed (negative)?' % x)

Better still in these situations is to throw to pdb.
But yes, you can put a formatted string in a check message.


From no.email at please.post  Sat Jul  4 17:10:44 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 21:10:44 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
	<7x4otsux7f.fsf@ruckus.brouhaha.com>
Message-ID: <h2oggj$n9p$1@reader1.panix.com>

In <7x4otsux7f.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

>kj <no.email at please.post> writes:
>>     sense = cmp(func(hi), func(lo))
>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"

>bisection search usually just requires the function to be continuous
>and to have its value cross the target somewhere between the endpoints,
>not be monotonic.

Try the algorithm I posted with lo = -pi/4, hi = 2*pi, func = cos,
target = -1, and see what you get...

>> I regard the very special case of func(hi)==func(lo)==target as
>> pathological (analogous to the fact that a stopped watch is "exactly
>> right" twice a day), and not one I care to support.

>I do think you should support that case, under the "do 'nothing'
>gracefully" principle.

You keep missing the point that this is an *internal* *helper*
*convenience* function, meant to abstract away common logic from
a handful of places and thus eliminate some code repetition within
a module.  It is *not* a library function intended to be called
from elsewhere.  So talk of "supporting" anything is besides the
point.  Any internal use of this function that applies it to a
non-strictly-monotonic function is, by assumption, an error.

kj


From no.email at please.post  Sat Jul  4 17:13:23 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 21:13:23 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
Message-ID: <h2ogli$n9p$2@reader1.panix.com>

In <7xzlbkti7z.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

>kj <no.email at please.post> writes:
>> This implies that code that uses *any* assert statement (other than
>> perhaps the trivial and meaningless ones like "assert True") is
>> liable to break, because whatever it is that these assert statements
>> are checking "on some occasions, ... would go unchecked, potentially
>> breaking your code."

>Yes, that implication is absolutely valid.  The purpose of assert
>statements is to debug the code, by checking for conditions that are
>supposed to be impossible.

Precisely.  As I've stated elsewhere, this is an internal helper
function, to be called only a few times under very well-specified
conditions.  The assert statements checks that these conditions
are as intended.  I.e. they are checks against the module writer's
programming errors.


From no.email at please.post  Sat Jul  4 17:14:45 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 21:14:45 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<mailman.2621.1246733010.8015.python-list@python.org>
Message-ID: <h2ogo5$n9p$3@reader1.panix.com>

In <mailman.2621.1246733010.8015.python-list at python.org> MRAB <python at mrabarnett.plus.com> writes:

>Paul Rubin wrote:
>> kj <no.email at please.post> writes:
>>> This implies that code that uses *any* assert statement (other than
>>> perhaps the trivial and meaningless ones like "assert True") is
>>> liable to break, because whatever it is that these assert statements
>>> are checking "on some occasions, ... would go unchecked, potentially
>>> breaking your code."
>> 
>> Yes, that implication is absolutely valid.  The purpose of assert
>> statements is to debug the code, by checking for conditions that are
>> supposed to be impossible.  Unless the program is broken (i.e.  the
>> impossible happened), no assert statement should ever trigger.
>> 
>Technically these are known as "invariants". An assertion will always be
>True if the program is bug-free, no matter what the user might throw at
>it; it's not the same as validation.

What *user* are you talking about???  I've stated a bazillion times
that this function is meant to be called only from within this
module.



From hanooter at gmail.com  Sat Jul  4 18:06:29 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 15:06:29 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com> 
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
Message-ID: <d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>

On Jul 4, 12:51?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> mclovin wrote:
> > OK then. I will try some of the strategies here but I guess things
> > arent looking too good. I need to run this over a dataset that someone
> > pickled. I need to run this 480,000 times so you can see my
> > frustration. So it doesn't need to be "real time" but it would be nice
> > it was done sorting this month.
>
> > Is there a "bet guess" strategy where it is not 100% accurate but much
> > faster?
>
> Well, I timed a run of a version of mine, and the scan is approx 5X
> longer than the copy-and-sort. ?Time arr_of_arr.flatten().sort() to
> see how quickly the copy and sort happens.So you could try a variant
> exploiting the following property:
> ? ? ?If you know the minimum length of a run that will be in the top 25,
> then the value for each of the most-frequent run entries must show up at
> positions n * stride and (n + 1) * stride (for some n). ?That should
> drastically reduce the scan cost, as long as stride is reasonably large.
>
> For my uniformly distributed 0..1024 values in 5M x 5M array,
> About 2.5 sec to flatten and sort.
> About 15 sec to run one of my heapish thingies.
> the least frequency encountered: 24716
> so, with stride at
>
> sum(flattened[:-stride:stride] == flattened[stride::stride]) == 1000
> So there are only 1000 points to investigate.
> With any distribution other than uniform, that should go _way_ down.
> So just pull out those points, use bisect to get their frequencies, and
> feed those results into the heap accumulation.
>
> --Scott David Daniels

I dont quite understand what you are saying but I know this: the times
the most common element appears varies greatly. Sometimes it appears
over 1000 times, and some times it appears less than 50. It all
depends on the density of the arrays I am analyzing.

like I said I need to do this 480,000 times so to get this done
realistically I need to analyse about 5 a second. It appears that the
average matrix size contains about 15 million elements.

I threaded my program using your code and I did about 1,000 in an hour
so it is still much too slow.

When I selected 1 million random elements to count, 8 out of the top
10 of those were in the top 25 of the precise way and 18 of the 25
were in the top 25 of the precise way. so I suppose that could be an
option.


From sajmikins at gmail.com  Sat Jul  4 18:22:47 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sat, 4 Jul 2009 15:22:47 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com>
Message-ID: <acee1a4b-275a-4343-8204-9812f3d90471@q11g2000yqi.googlegroups.com>

On Jul 4, 12:30?pm, kj <no.em... at please.post> wrote:
> In <mailman.2611.1246721197.8015.python-l... at python.org> "Pablo Torres N." <tn.pa... at gmail.com> writes:
>
>
>
> >On Sat, Jul 4, 2009 at 10:05, kj<no.em... at please.post> wrote:
> >>>http://docs.python.org/reference/simple_stmts.html#grammar-token-asse...
> >tmt
> >>>"The current code generator emits no code for an assert statement when op=
> >timization is requested at compile time."
>
> >> Sorry, this doesn't say anything like "don't use assertions to test
> >> argument values". =C2=A0I'm aware of the fact that assertions are silence=
> >d
> >> under certain circumstances. =C2=A0But where does the principle 1. in
> >> your first reply come from? =C2=A0I've never seen it before, and would
> >> like to understand the reasoning behind it.
>
> >> kj
> >> --
> >>http://mail.python.org/mailman/listinfo/python-list
>
> >But...if no code is generated for assertions on some occasions, then the
> >parameters would go unchecked, potentially breaking your code in said
> >occasions.
>
> This implies that code that uses *any* assert statement (other than
> perhaps the trivial and meaningless ones like "assert True") is
> liable to break, because whatever it is that these assert statements
> are checking "on some occasions, ... would go unchecked, potentially
> breaking your code."
>
> I'm beginning to think that the original "precept" was simply "cargo
> cult," i.e. one of those rules that are parroted without being
> fully understood.
>
> As I wrote in my original post, the function I posted was an internal
> ("helper") function, not to be used outside of the file. ?This fact
> was further (ahem) underscored by the leading underscore in the
> function's name. ?Under these circumstances, the assert statements
> seem to me perfectly in keeping with the intended use for them.
>
> kj

Assertions are for you, the programmer, to check that your
understanding of the code is correct (or not, i.e. if the assertion
fails.)

It's unfortunately not uncommon to see code where the assert statement
is used as an integral part of the processing, or, in other words,
where running the code with '-O' will cause changes in the way the it
runs.

In the code you posted, the assert statements seem to be checking that
other code/algorithms aren't (will never) pass that function "out of
bounds" arguments.  Perfectly valid IMO.  Since it's an internal
helper function you can (should) know that client code will /always/
call it with valid values, the asserts simply make your intuition or
knowledge explicit in a way that will show up dramatically if you're
wrong about that (i.e. if there's some problem elsewhere in the code
feeding that function.)

Assertions should never fail, which is why you can (or should be able
to without breaking your code) remove them entirely and know that your
program will run identically.  That's why folks are quick to jump on
cases where assertions are used as control-flow constructs.  (In your
function, however, they aren't.)

In a sense, assertions /are/ meaningless, except to the programmer.

FWIW, you can use "if __debug__:" and put anything you like in the
statement suite and the whole if statement goes away when run with '-
O'. Sort of a "super-assert".

Regards,
~Simon


From http  Sat Jul  4 18:24:01 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 15:24:01 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
	<7x4otsux7f.fsf@ruckus.brouhaha.com>
	<h2oggj$n9p$1@reader1.panix.com>
Message-ID: <7xljn484u6.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
> >bisection search usually just requires the function to be continuous
> >and to have its value cross the target somewhere between the endpoints,
> >not be monotonic.
> 
> Try the algorithm I posted with lo = -pi/4, hi = 2*pi, func = cos,
> target = -1, and see what you get...

Sorry, my comment was poorly phrase.  Bisection search usually is
phrased in terms of solving f(x)=0 where f is continuous and if the
initial endpoints are a and b, then f(a) and f(b) have opposite sign.

> You keep missing the point that this is an *internal* *helper*
> *convenience* function, ...  Any internal use of this function that
> applies it to a non-strictly-monotonic function is, by assumption,
> an error.

In that case there are better algorithms you can use.  But didn't this
thread start out asking what version of the code was best suited for
presentation to students?  In that case, the function's preconditions
should be stated explicitly and not be narrower than necessary.


From python at mrabarnett.plus.com  Sat Jul  4 18:29:41 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 04 Jul 2009 23:29:41 +0100
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
Message-ID: <4A4FD7D5.6050201@mrabarnett.plus.com>

mclovin wrote:
[snip]
> like I said I need to do this 480,000 times so to get this done
> realistically I need to analyse about 5 a second. It appears that the
> average matrix size contains about 15 million elements.
> 
> I threaded my program using your code and I did about 1,000 in an hour
> so it is still much too slow.
> 
> When I selected 1 million random elements to count, 8 out of the top
> 10 of those were in the top 25 of the precise way and 18 of the 25
> were in the top 25 of the precise way. so I suppose that could be an
> option.

The values are integers, aren't they? What is the range of values?


From hanooter at gmail.com  Sat Jul  4 18:33:38 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 15:33:38 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com> 
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<mailman.2623.1246746585.8015.python-list@python.org>
Message-ID: <e1536b4d-c9ca-4376-8b98-f2b7994d2d18@q11g2000yqi.googlegroups.com>

On Jul 4, 3:29?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> mclovin wrote:
>
> [snip]
>
> > like I said I need to do this 480,000 times so to get this done
> > realistically I need to analyse about 5 a second. It appears that the
> > average matrix size contains about 15 million elements.
>
> > I threaded my program using your code and I did about 1,000 in an hour
> > so it is still much too slow.
>
> > When I selected 1 million random elements to count, 8 out of the top
> > 10 of those were in the top 25 of the precise way and 18 of the 25
> > were in the top 25 of the precise way. so I suppose that could be an
> > option.
>
> The values are integers, aren't they? What is the range of values?

There are appox 550k unique values with a range of 0-2million with
gaps.


From pavlovevidence at gmail.com  Sat Jul  4 18:47:57 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 4 Jul 2009 15:47:57 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>
	<mailman.2556.1246624444.8015.python-list@python.org>
Message-ID: <94eaeb9d-fe90-45fb-99ee-8846eb8cb19e@r33g2000yqn.googlegroups.com>

On Jul 3, 5:34?am, Jack Diederich <jackd... at gmail.com> wrote:
> On Thu, Jul 2, 2009 at 2:36 PM, Carl Banks<pavlovevide... at gmail.com> wrote:
> > Warning: objects with a __del__ attribute prevent reference cycle
> > detection, which can potentially lead to memory (and resource) leaks.
> > So you must be careful to avoid creating reference loops with that
> > object.
>
> WARNING-er: As Carl points out, adding a __del__ method actually makes
> it /less/ likely that your object will be cleaned up.

No I wasn't pointing that out, and I don't really agree with it.  (You
can't really say it is "more likely" or "less likely" without
considering the skill and patience of the programmer, and there are
many programmers who are up to the task.)

__del__ can succeed with care, and if you are willing to give up a
certain amount of flexibility and portability

I don't recommend going that way.  For one thing RAII isn't quite so
wonderful in Python's dynamic environment as it is in C++'s static
universe, and people seem to expect more from it than they get.
Second, relying on implementation-dependent behavior is not a good
thing and can set you up for problems later, something few people
expect to happen to them but it does more often than they think.
(Search comp.lang.python for a thread started by Warren DeLano for an
example of someone who got bit hard by such a change he should have
seen coming.)  But still I leave that for them to risk for themselves.


[snip]
>?If you care enough about a resource to write a __del__ method
> you care enough to clean it up explicitly. ?'with' blocks are very
> nice for that.

The OP already said with blocks won't suffice since the resources are
long-lived objects that aren't limited to a single scope.


Carl Banks


From Scott.Daniels at Acm.Org  Sat Jul  4 18:50:23 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 15:50:23 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
Message-ID: <4A4FDCAF.8010209@Acm.Org>

mclovin wrote:
> On Jul 4, 12:51 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>> mclovin wrote:
>>> OK then. I will try some of the strategies here but I guess things
>>> arent looking too good. I need to run this over a dataset that someone
>>> pickled. I need to run this 480,000 times so you can see my
>>> frustration. So it doesn't need to be "real time" but it would be nice
>>> it was done sorting this month.
>>> Is there a "bet guess" strategy where it is not 100% accurate but much
>>> faster?
>>
>> Well, I timed a run of a version of mine, and the scan is approx 5X
>> longer than the copy-and-sort.  Time arr_of_arr.flatten().sort() to
>> see how quickly the copy and sort happens.So you could try a variant
>> exploiting the following property:
>>      If you know the minimum length of a run that will be in the top 25,
>> then the value for each of the most-frequent run entries must show up at
>> positions n * stride and (n + 1) * stride (for some n).  That should
>> drastically reduce the scan cost, as long as stride is reasonably large....
>>
>> sum(flattened[:-stride:stride] == flattened[stride::stride]) == 1000
>> So there are only 1000 points to investigate.
>> With any distribution other than uniform, that should go _way_ down.
>> So just pull out those points, use bisect to get their frequencies, and
>> feed those results into the heap accumulation.
>>
>> --Scott David Daniels
> 
> I dont quite understand what you are saying but I know this: the times
> the most common element appears varies greatly. Sometimes it appears
> over 1000 times, and some times it appears less than 50. It all
> depends on the density of the arrays I am analyzing.

Here's a heuristic replacement for my previous frequency code:
I've tried to mark where you could fudge numbers if the run time
is at all close.

def frequency(arr_of_arr, N, stride=100)
     '''produce (freq, value) pairs for data in arr_of_arr.

     Tries to produce > N pairs.  stride is a guess at half
     the length of the shortest run in the top N runs.
     '''
     # if the next two lines are too slow, this whole approach is toast
     data = arr_of_arr.flatten()  # big allocation
     data.sort() # a couple of seconds for 25 million ints

     # stride is a length forcing examination of a run.
     sampled = data[::stride]
     # Note this is a view into data, and is still sorted.
     # We know that any run of length 2 * stride - 1 in data _must_ have
     # consecutive entries in sampled.  Compare them "in parallel"
     matches = sampled[:-1] == sampled[1:]
     # matches is True or False for stride-separated values from sampled
     candidates = sum(matches) # count identified matches

     # while candidates is huge, keep trying with a larger stride
     while candidates > N *10: # 10 -- heuristic
         stride *= 2 # # heuristic increase
         sampled = data[::stride]
         matches = sampled[:-1] == sampled[1:]
         candidates = sum(matches)

     # if we got too few, move stride down:
     while candidates < N * 3: # heuristic slop for long runs
         stride //= 2 # heuristic decrease
         sampled = data[::stride]
         matches = sampled[:-1] == sampled[1:]
         candidates = sum(matches)

     # Here we have a "nice" list of candidates that is likely
     # to include every run we actually want. sampled[matches] is
     # the sorted list of candidate values.  It may have duplicates
     former = None
     past = 0
     # In the loop here we only use sampled to the pick values we
     # then go find in data.  We avoid checking for same value twice
     for value in sampled[matches]:
         if value == former:
             continue # A long run: multiple matches in sampled
         former = value # Make sure we only try this one once
         # find the beginning of the run
         start = bisect.bisect_left(data, value, past)
         # find the end of the run (we know it is at least stride long)
         past = bisect.bisect_right(data, value, start + stride)
         yield past - start, value # produce frequency, value data

--Scott David Daniels
Scott.Daniels at Acm.Org


From python at mrabarnett.plus.com  Sat Jul  4 19:05:50 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 05 Jul 2009 00:05:50 +0100
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <e1536b4d-c9ca-4376-8b98-f2b7994d2d18@q11g2000yqi.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>	<mailman.2623.1246746585.8015.python-list@python.org>
	<e1536b4d-c9ca-4376-8b98-f2b7994d2d18@q11g2000yqi.googlegroups.com>
Message-ID: <4A4FE04E.1050202@mrabarnett.plus.com>

mclovin wrote:
> On Jul 4, 3:29 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> mclovin wrote:
>>
>> [snip]
>>
>>> like I said I need to do this 480,000 times so to get this done
>>> realistically I need to analyse about 5 a second. It appears that the
>>> average matrix size contains about 15 million elements.
>>> I threaded my program using your code and I did about 1,000 in an hour
>>> so it is still much too slow.
>>> When I selected 1 million random elements to count, 8 out of the top
>>> 10 of those were in the top 25 of the precise way and 18 of the 25
>>> were in the top 25 of the precise way. so I suppose that could be an
>>> option.
>> The values are integers, aren't they? What is the range of values?
> 
> There are appox 550k unique values with a range of 0-2million with
> gaps.

I've done a little experimentation with lists (no numpy involved) and
found that I got a x2 speed increase if I did the counting using a list,
something like this:

counts = [0] * 2000000
for x in values:
     counts[x] += 1
counts = dict(e for e in enumerate(values) if e[1] != 0)


From hkmshb at gmail.com  Sat Jul  4 19:18:50 2009
From: hkmshb at gmail.com (Klone)
Date: Sat, 4 Jul 2009 16:18:50 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
	<b0b2ff61-9023-474c-b114-863107781971@y7g2000yqa.googlegroups.com> 
	<4d99b710-45f1-42dc-b80c-1894af26db42@p29g2000yqh.googlegroups.com>
Message-ID: <46ce50ea-0272-4285-ab06-65c4e53a1e99@k8g2000yqn.googlegroups.com>

Thank you all. I think I get the gist and am about trying your
suggestions.


From nagle at animats.com  Sat Jul  4 19:35:08 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 04 Jul 2009 16:35:08 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xvdm8thpo.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
Message-ID: <4a4fe6cb$0$1591$742ec2ed@news.sonic.net>

Paul Rubin wrote:
> John Nagle <nagle at animats.com> writes:
>> Python doesn't have a "switch" or "case" statement, and when
>> you need a state machine with many states, that makes for painful,
>> slow code.  ...
>> There's a comment in the code that it would be useful
>> to run a few billion lines of HTML through an instrumented version
>> of the parser to decide in which order the IF statements should be
>> executed.  You shouldn't have to do that.
> 
> In that particular program it would probably be better to change those
> if/elif/elif/else constructs to dictionary lookups.  I see the program
> already does that for some large tables.

    A dictionary lookup (actually, several of them) for every
input character is rather expensive. Tokenizers usually index into
a table of character classes, then use the character class index in
a switch statement.

    This is an issue that comes up whenever you have to parse some formal
structure, from XML/HTML to Pickle to JPEG images to program source.

    If Python could figure out what's a constant and what isn't during
compilation, this sort of thing could be much more efficient.  In fact,
you don't even need a switch statement at the source level, if the
language is such that the compiler can figure out when "elif" clauses
are mutually exclusive.

    The temptation is to write tokenizers in C, but that's an admission
of language design failure.

    (A general problem with Python is "hidden dynamism".  That is,
changes to variables that can't be found by examining the source.
This is a killer for optimizations. One could take the position that any
module variable with exactly one visible assignment to it is, in fact,
only assigned in one place, and if the right hand side is a constant,
the variable is a constant.  This would break some programs doing funny
stuff with "eval", or using some of the backdoor ways to modify variables,
but that's very rare in practice.  In return, you get the ability to
hard-compile more of Python into fast code.  I'm thinking Shed Skin here,
not yet another attempt at a JIT system.)

    On the other hand, trying to do this in Perl, where you can't even index
strings, is far worse.
	
				John Nagle


From http  Sat Jul  4 19:48:19 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 16:48:19 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <7xfxdcqabg.fsf@ruckus.brouhaha.com>

John Nagle <nagle at animats.com> writes:
>     A dictionary lookup (actually, several of them) for every
> input character is rather expensive. Tokenizers usually index into
> a table of character classes, then use the character class index in
> a switch statement.

Maybe you could use a regexp (and then have -two- problems...) to
find the token boundaries, then a dict to identify the actual token.
Tables of character classes seem a bit less attractive in the Unicode
era than in the old days.


From davea at ieee.org  Sat Jul  4 19:53:48 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 19:53:48 -0400
Subject: Zipped Python?
In-Reply-To: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
References: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
Message-ID: <4A4FEB8C.4040302@ieee.org>

Jeremy Cowles wrote:
> Hi all,
>
> I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e. no
> install). My intentions are to use it for a distributed computing project
> (PyMW) where there is no guarantee that Python is installed on the worker
> machines and an interactive install is out of the question.
>
> I've been looking around, but I haven't been able to turn anything useful up
> so far. Any help would be appreciated.
>
> --
> Jeremy
>
>
>   
How about portable python:
      http://www.portablepython.com/

or Movable Python:
       http://www.voidspace.org.uk/python/movpy/


No experience with either, but they bear looking at.



From matt at tplus1.com  Sat Jul  4 20:03:38 2009
From: matt at tplus1.com (Matthew Wilson)
Date: Sun, 05 Jul 2009 00:03:38 GMT
Subject: Does cProfile include IO wait time?
Message-ID: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>

I have a command-line script that loads about 100 yaml files.  It takes
2 or 3 seconds.  I profiled my code and I'm using pstats to find what is
the bottleneck.

Here's the top 10 functions, sorted by internal time:

    In [5]: _3.sort_stats('time').print_stats(10)
    Sat Jul  4 13:25:40 2009    pitz_prof

             756872 function calls (739759 primitive calls) in 8.621 CPU seconds

       Ordered by: internal time
       List reduced from 1700 to 10 due to restriction <10>

       ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        15153    0.446    0.000    0.503    0.000 build/bdist.linux-i686/egg/yaml/reader.py:134(forward)
        30530    0.424    0.000    0.842    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:142(need_more_tokens)
        98037    0.423    0.000    0.423    0.000 build/bdist.linux-i686/egg/yaml/reader.py:122(peek)
         1955    0.415    0.000    1.265    0.001 build/bdist.linux-i686/egg/yaml/scanner.py:1275(scan_plain)
        69935    0.381    0.000    0.381    0.000 {isinstance}
        18901    0.329    0.000    3.908    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:113(check_token)
         5414    0.277    0.000    0.794    0.000 /home/matt/projects/pitz/pitz/__init__.py:34(f)
        30935    0.258    0.000    0.364    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:276(stale_possible_simple_keys)
        18945    0.192    0.000    0.314    0.000 /usr/local/lib/python2.6/uuid.py:180(__cmp__)
         2368    0.172    0.000    1.345    0.001 build/bdist.linux-i686/egg/yaml/parser.py:268(parse_node)

I expected to see a bunch of my IO file-reading code in there, but I don't.  So
this makes me think that the profiler uses CPU time, not
clock-on-the-wall time.

I'm not an expert on python profiling, and the docs seem sparse.  Can I
rule out IO as the bottleneck here?  How do I see the IO consequences?

TIA

Matt


From jeremy.cowles at gmail.com  Sat Jul  4 20:03:44 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Sat, 4 Jul 2009 17:03:44 -0700
Subject: Zipped Python?
In-Reply-To: <4A4FEB8C.4040302@ieee.org>
References: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
	<4A4FEB8C.4040302@ieee.org>
Message-ID: <373cf0740907041703g5250fc9cg346c2c6f2b6d992c@mail.gmail.com>

>
> I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e. no
>> install). My intentions are to use it for a distributed computing project
>> (PyMW) where there is no guarantee that Python is installed on the worker
>> machines and an interactive install is out of the question.
>>
>> I've been looking around, but I haven't been able to turn anything useful
>> up
>> so far. Any help would be appreciated.
>>
>>
>>  How about portable python:
>     http://www.portablepython.com/
>
> or Movable Python:
>      http://www.voidspace.org.uk/python/movpy/
>

Sorry, forgot - I need something that will work for Windows, Linux and Mac.
It could be 3 different distros (zips), but I need something for all three.

Both portable python and movable Python are Windows only.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/9a682c62/attachment.html>

From ldo at geek-central.gen.new_zealand  Sat Jul  4 20:12:22 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 05 Jul 2009 12:12:22 +1200
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
Message-ID: <h2or56$bko$1@lust.ihug.co.nz>

In message <1beffd94-cfe6-4cf6-
bd48-2ccac8637796 at j32g2000yqh.googlegroups.com>, ryles wrote:

>>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which
>>>> # iter() will do. Sorry guys!
> 
> Please don't let this happen to you too ;)

Strange. others have got told off for using "== None" instead of "is None" 
<http://groups.google.co.nz/group/comp.lang.python/msg/a1f3170fa202af57>, 
and yet it turns out Python itself does exactly the same thing.



From emile at fenx.com  Sat Jul  4 21:00:29 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sat, 04 Jul 2009 18:00:29 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <h2otvh$tpv$1@ger.gmane.org>

On 7/4/2009 12:33 AM mclovin said...
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
> 
> so I set up a dictionary to handle the counting so when I am
> iterating  I 

   ** up the count on the corrosponding dictionary element **

Right at this point, instead of or in addition to counting, why not save 
the large array index in a list?  Then when you've identified the 25 
most common elements you'll already have a list of pointer to the 
instances to work from.

Emile




From sgm at objexx.com  Sat Jul  4 21:15:43 2009
From: sgm at objexx.com (SK)
Date: Sat, 4 Jul 2009 18:15:43 -0700 (PDT)
Subject: multiprocessing and freezing on Windows
References: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>
Message-ID: <a205db1d-a801-4774-bfa1-124a723ea71b@p36g2000prn.googlegroups.com>

To add a bit more information, I found that I needed to patch
get_command_line in multiprocessing/forking.py replacing:

        if getattr(sys, 'frozen', False):
            return [sys.executable, '--multiprocessing-fork']
        else:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']

with:

        if WINEXE:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']
        elif getattr(sys, 'frozen', False):
            return [sys.executable, '--multiprocessing-fork']
        else:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']

and then using py2exe I can get a working "frozen" package if I
include pythonw.exe and a subset of Python's Lib directory in my
package and call multiprocessing.set_executable to point to that
pythonw.exe.

Does the above patch address a real bug?

Is packaging with multiprocessing supposed to be this hard? If so,
some documentation is needed.


From nobody at nowhere.com  Sat Jul  4 21:25:38 2009
From: nobody at nowhere.com (Nobody)
Date: Sun, 05 Jul 2009 02:25:38 +0100
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <pan.2009.07.05.01.25.37.813000@nowhere.com>

On Sat, 04 Jul 2009 16:35:08 -0700, John Nagle wrote:

>     The temptation is to write tokenizers in C, but that's an admission
> of language design failure.

The only part that really needs to be written in C is the DFA loop. The
code to construct the state table from regexps could be written
entirely in Python, but I don't see any advantage to doing so.



From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:27:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:27:30 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<mailman.2621.1246733010.8015.python-list@python.org>
	<h2ogo5$n9p$3@reader1.panix.com>
Message-ID: <025ff310$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 21:14:45 +0000, kj wrote:

>>Technically these are known as "invariants". An assertion will always be
>>True if the program is bug-free, no matter what the user might throw at
>>it; it's not the same as validation.
> 
> What *user* are you talking about???  I've stated a bazillion times that
> this function is meant to be called only from within this module.

In that case, you would be the user, and like any user, you might 
accidentally call the function with invalid data.

I believe this discussion started because you are presenting this as code 
for novices. In that case, it is absolutely important that you start off 
by teaching them the Right Way to do things. As a general rule, the Right 
Way is to do an explicit test and raise rather than use assert.

In production code, "internal use only" code is a grey area where assert 
is sometimes justified (although I'll point out that in practice, code 
written for internal use only has a habit of being called by others). But 
you're not writing production code, you're writing *teaching code*, where 
even more important than code correctness is user education.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:31:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:31:23 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
Message-ID: <025ff3f9$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 15:06:29 -0700, mclovin wrote:

> like I said I need to do this 480,000 times so to get this done
> realistically I need to analyse about 5 a second. It appears that the
> average matrix size contains about 15 million elements.

Have you considered recording the element counts as you construct the 
arrays? This will marginally increase the time it takes to build the 
array, but turn finding the most frequent elements into a very quick 
operation.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:35:31 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:35:31 GMT
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<h2or56$bko$1@lust.ihug.co.nz>
Message-ID: <025ff4f1$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 12:12:22 +1200, Lawrence D'Oliveiro wrote:

> In message <1beffd94-cfe6-4cf6-
> bd48-2ccac8637796 at j32g2000yqh.googlegroups.com>, ryles wrote:
> 
>>>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which
>>>>> # iter() will do. Sorry guys!
>> 
>> Please don't let this happen to you too ;)
> 
> Strange. others have got told off for using "== None" instead of "is
> None"
> <http://groups.google.co.nz/group/comp.lang.python/msg/
a1f3170fa202af57>,
> and yet it turns out Python itself does exactly the same thing.

That's not "strange", that's a bug. Did you report it to the tracker?



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:36:13 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:36:13 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
Message-ID: <025ff51b$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 11:10:48 -0700, Paul Rubin wrote:

> Anyway, Python's overloading of bool(...) is yet another misfeature and
> although it's convenient, the "explicit is better than implicit"
> principle indicates to avoid that sort of trick.

"Overloading of bool()"?

I don't understand what that means -- you mean you dislike the ability to 
overload __bool__ (__nonzero__ in older Pythons)? That seems strange. 
Python allows you to overload __int__ and __str__ and __float__, why is 
__bool__ a misfeature? If that's what you mean, then I'm perplexed.

Or do you mean that all Python objects are interpretable in a truth 
context? If that's what you mean, then I'm not perplexed, I'm sure you're 
utterly wrong. Certain people -- a tiny minority -- keep trying to argue 
that the ability to say "if obj" for arbitrary objects is somehow a bad 
thing, and their arguments seem to always boil down to:

"If you write code that assumes that only bools have a truth value, then 
surprising things will happen because all objects have a truth value."

Well duh.

If you think you have a better reason for calling the truth value of 
arbitrary objects a "misfeature", I'd like to hear it.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:39:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:39:33 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
Message-ID: <025ff5e2$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 07:19:48 -0700, Scott David Daniels wrote:

> Actually the next step is to maintain a min-heap as you run down the
> sorted array.  Something like:

Not bad.

I did some tests on it, using the following sample data:

arr = np.array([xrange(i, i+7000) for i in xrange(143)] + 
      [[750]*7000] + [xrange(3*i, 3*i+7000) for i in xrange(142)])


and compared your code against the following simple function:


def count(arr, N):
    D = {}
    for v in arr:
        for x in v:
            D[x] = D.get(x, 0) + 1
    freq = []
    for el, f in D.iteritems():
        freq.append((f, el))
    return sorted(freq, reverse=True)[:N]


As a rough figure, your min-heap code is approximately twice as fast as 
mine.

To the OP: I think you should start profiling your code and find out 
exactly *where* it is slow and concentrate on that. I think that trying a 
heuristic to estimate the most frequent elements by taking a random 
sample is likely to be a mistake -- whatever you're trying to accomplish 
with the frequency counts, the use of such a heuristic will mean that 
you're only approximately accomplishing it.



-- 
Steven


From ben+python at benfinney.id.au  Sat Jul  4 22:09:12 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 05 Jul 2009 12:09:12 +1000
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <87tz1rrid3.fsf@benfinney.id.au>

John Nagle <nagle at animats.com> writes:

>    A dictionary lookup (actually, several of them) for every input
> character is rather expensive. Tokenizers usually index into a table
> of character classes, then use the character class index in a switch
> statement.
> 
>    This is an issue that comes up whenever you have to parse some
> formal structure, from XML/HTML to Pickle to JPEG images to program
> source.
> [?] 
>    The temptation is to write tokenizers in C, but that's an admission
> of language design failure.

This sounds like a job for <URL:http://pyparsing.wikispaces.com/>
Pyparsing.

-- 
 \          ?Better not take a dog on the space shuttle, because if he |
  `\   sticks his head out when you're coming home his face might burn |
_o__)                                                up.? ?Jack Handey |
Ben Finney


From benjamin.kaplan at case.edu  Sat Jul  4 22:28:23 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Sat, 4 Jul 2009 22:28:23 -0400
Subject: Zipped Python?
In-Reply-To: <373cf0740907041703g5250fc9cg346c2c6f2b6d992c@mail.gmail.com>
References: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
	<4A4FEB8C.4040302@ieee.org>
	<373cf0740907041703g5250fc9cg346c2c6f2b6d992c@mail.gmail.com>
Message-ID: <ec96e1390907041928j136c3296nfcdc478279bbabef@mail.gmail.com>

On Sat, Jul 4, 2009 at 8:03 PM, Jeremy Cowles<jeremy.cowles at gmail.com> wrote:
>>> I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e.
>>> no
>>> install). My intentions are to use it for a distributed computing project
>>> (PyMW) where there is no guarantee that Python is installed on the worker
>>> machines and an interactive install is out of the question.
>>>
>>> I've been looking around, but I haven't been able to turn anything useful
>>> up
>>> so far. Any help would be appreciated.
>>>
>>>
>> How about portable python:
>> ? ? http://www.portablepython.com/
>>
>> or Movable Python:
>> ? ? ?http://www.voidspace.org.uk/python/movpy/
>
> Sorry, forgot - I need something that will work for Windows, Linux and Mac.
> It could be 3 different distros (zips), but I need something for all three.
> Both portable python and movable Python are Windows only.

OS X and most, if not all, Linux distributions come with Python
preinstalled (they use them for system features) so no one bothered to
make something like Portable Python for them.

> --
> http://mail.python.org/mailman/listinfo/python-list
>
>


From nagle at animats.com  Sat Jul  4 23:15:11 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 04 Jul 2009 20:15:11 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xfxdcqabg.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
Message-ID: <4a501a5e$0$1640$742ec2ed@news.sonic.net>

Paul Rubin wrote:
> John Nagle <nagle at animats.com> writes:
>>     A dictionary lookup (actually, several of them) for every
>> input character is rather expensive. Tokenizers usually index into
>> a table of character classes, then use the character class index in
>> a switch statement.
> 
> Maybe you could use a regexp (and then have -two- problems...) to
> find the token boundaries, then a dict to identify the actual token.
> Tables of character classes seem a bit less attractive in the Unicode
> era than in the old days.

    I want to see a regular expression that expresses the HTML 5 token
parsing rules, including all the explicitly specified error handling.

    Here's some actual code, from "tokenizer.py".  This is called once
for each character in an HTML document, when in "data" state (outside
a tag).  It's straightforward code, but look at all those
dictionary lookups.

     def dataState(self):
         data = self.stream.char()

         # Keep a charbuffer to handle the escapeFlag
         if self.contentModelFlag in\
           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
             if len(self.lastFourChars) == 4:
                 self.lastFourChars.pop(0)
             self.lastFourChars.append(data)

         # The rest of the logic
         if data == "&" and self.contentModelFlag in\
           (contentModelFlags["PCDATA"], contentModelFlags["RCDATA"]) and not\
           self.escapeFlag:
             self.state = self.states["entityData"]
         elif data == "-" and self.contentModelFlag in\
           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and not\
           self.escapeFlag and "".join(self.lastFourChars) == "<!--":
             self.escapeFlag = True
             self.tokenQueue.append({"type": "Characters", "data":data})
         elif (data == "<" and (self.contentModelFlag == contentModelFlags["PCDATA"]
                                or (self.contentModelFlag in
                                    (contentModelFlags["CDATA"],
                                     contentModelFlags["RCDATA"]) and
                                    self.escapeFlag == False))):
             self.state = self.states["tagOpen"]
         elif data == ">" and self.contentModelFlag in\
           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and\
           self.escapeFlag and "".join(self.lastFourChars)[1:] == "-->":
             self.escapeFlag = False
             self.tokenQueue.append({"type": "Characters", "data":data})
         elif data == EOF:
             # Tokenization ends.
             return False
         elif data in spaceCharacters:
             # Directly after emitting a token you switch back to the "data
             # state". At that point spaceCharacters are important so they are
             # emitted separately.
             self.tokenQueue.append({"type": "SpaceCharacters", "data":
               data + self.stream.charsUntil(spaceCharacters, True)})
             # No need to update lastFourChars here, since the first space will
             # have already broken any <!-- or --> sequences
         else:
             chars = self.stream.charsUntil(("&", "<", ">", "-"))
             self.tokenQueue.append({"type": "Characters", "data":
               data + chars})
             self.lastFourChars += chars[-4:]
             self.lastFourChars = self.lastFourChars[-4:]
         return True



					John Nagle


From kyosohma at gmail.com  Sat Jul  4 23:17:07 2009
From: kyosohma at gmail.com (Mike Driscoll)
Date: Sat, 4 Jul 2009 20:17:07 -0700 (PDT)
Subject: Pyowa is this Monday!
Message-ID: <7224400c-cadc-403f-b090-74cb49373dee@h11g2000yqb.googlegroups.com>

Hi,

The next Pyowa meeting is on Monday, July 6th from 7-9 p.m. We will be
at the Marshall County Sheriff's Office (directions on website).
Currently, the plan is to have a talk about Python at Fisher/Emerson
that will segue into a general discussion of what we do with our
favorite programming language. Be prepared to share!

We may have another presentation in our Standard Library series as
well or just something random. Let me know if you think you'll be
there. Pop & water will be provided. We hope to see you there!

--------------------------
Mike Driscoll

http://www.pyowa.org
http://pyowa.blip.tv/
http://twitter.com/pyowa
http://upcoming.yahoo.com/event/2853430/
Mailing list: http://pyowalist.pythonlibrary.org/listinfo.cgi/pyowa-pythonlibrary.org


From aahz at pythoncraft.com  Sat Jul  4 23:37:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 4 Jul 2009 20:37:16 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <h2p75c$65r$1@panix3.panix.com>

In article <4a501a5e$0$1640$742ec2ed at news.sonic.net>,
John Nagle  <nagle at animats.com> wrote:
>
>    Here's some actual code, from "tokenizer.py".  This is called once
>for each character in an HTML document, when in "data" state (outside
>a tag).  It's straightforward code, but look at all those
>dictionary lookups.
>
>     def dataState(self):
>         data = self.stream.char()
>
>         # Keep a charbuffer to handle the escapeFlag
>         if self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
>             if len(self.lastFourChars) == 4:
>                 self.lastFourChars.pop(0)
>             self.lastFourChars.append(data)
>
>         # The rest of the logic
>         if data == "&" and self.contentModelFlag in\
>           (contentModelFlags["PCDATA"], contentModelFlags["RCDATA"]) and not\
>           self.escapeFlag:
>             self.state = self.states["entityData"]
>         elif data == "-" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and not\
>           self.escapeFlag and "".join(self.lastFourChars) == "<!--":
>             self.escapeFlag = True
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif (data == "<" and (self.contentModelFlag == contentModelFlags["PCDATA"]
>                                or (self.contentModelFlag in
>                                    (contentModelFlags["CDATA"],
>                                     contentModelFlags["RCDATA"]) and
>                                    self.escapeFlag == False))):
>             self.state = self.states["tagOpen"]
>         elif data == ">" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and\
>           self.escapeFlag and "".join(self.lastFourChars)[1:] == "-->":
>             self.escapeFlag = False
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif data == EOF:
>             # Tokenization ends.
>             return False
>         elif data in spaceCharacters:
>             # Directly after emitting a token you switch back to the "data
>             # state". At that point spaceCharacters are important so they are
>             # emitted separately.
>             self.tokenQueue.append({"type": "SpaceCharacters", "data":
>               data + self.stream.charsUntil(spaceCharacters, True)})
>             # No need to update lastFourChars here, since the first space will
>             # have already broken any <!-- or --> sequences
>         else:
>             chars = self.stream.charsUntil(("&", "<", ">", "-"))
>             self.tokenQueue.append({"type": "Characters", "data":
>               data + chars})
>             self.lastFourChars += chars[-4:]
>             self.lastFourChars = self.lastFourChars[-4:]
>         return True

Every single "self." is a dictionary lookup.  Were you referring to
those?  If not, I don't see your point.  If yes, well, that's kind of the
whole point of using Python.  You do pay a performance penalty.  You can
optimize out some lookups, but you need to switch to C for some kinds of
computationally intensive algorithms.  In this case, you can probably get
a large boost out of Pysco or Cython or Pyrex.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From tn.pablo at gmail.com  Sun Jul  5 00:26:39 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sat, 4 Jul 2009 23:26:39 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2on0d$i57$1@ger.gmane.org>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com> <h2on0d$i57$1@ger.gmane.org>
Message-ID: <fdd00b510907042126n4d0ca869wbe892777bab00690@mail.gmail.com>

On Sat, Jul 4, 2009 at 18:01, Dennis Lee Bieber<wlfraed at ix.netcom.com> wrote:
> ? ? ? ?Do you really want to inflict novices with the subtleties of when
> "assert" is a proper structure to use?

I'll second that.  This very thread is proof that assertions are polemic, so
maybe you (kj) should just save your student's sanity and stick to good old
conditionals :-)

As for your initial question, I think, thirty four emails after, that yes, your
function is a bit too clever and you should sacrifice some generality in order
to make it more readable.


-- 
Pablo Torres N.


From pavlovevidence at gmail.com  Sun Jul  5 01:51:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 4 Jul 2009 22:51:52 -0700 (PDT)
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com> 
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <4c2c7b44-23cd-43b4-8086-1b7cf6a14954@n11g2000yqb.googlegroups.com>

On Jul 4, 4:35?pm, John Nagle <na... at animats.com> wrote:
> ? ? The temptation is to write tokenizers in C, but that's an admission
> of language design failure.

No it isn't.  It's only a failure of Python to be the language that
does everything *you* want.

Carl Banks


From http  Sun Jul  5 02:17:21 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 23:17:21 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xfxdbk61a.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Certain people -- a tiny minority -- keep trying to argue 
> that the ability to say "if obj" for arbitrary objects is somehow a bad 
> thing, and their arguments seem to always boil down to:
> "If you write code that assumes that only bools have a truth value, then 
> surprising things will happen because all objects have a truth value."

I'd put it under the general rubric of "explicit is better than
implicit".  The language shouldn't do silly automatic typecasts all
over the place.  Yes, it saves a few keystrokes to say "if x:" instead
of "if len(x)==0:" or even "if bool(x):", but if I program in a style
where I like to think I know the type of something when I use it, I'd
like the interpreter to let me know when I'm wrong instead of
proceeding silently.


From nick at craig-wood.com  Sun Jul  5 03:30:04 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Sun, 05 Jul 2009 02:30:04 -0500
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <slrnh50ljc.1jp.nick@irishsea.home.craig-wood.com>

John Nagle <nagle at animats.com> wrote:
>      As an example of code that really needs to run fast, but is
>  speed-limited by Python's limitations, see "tokenizer.py" in
> 
>  	http://code.google.com/p/html5lib/
> 
>  This is a parser for HTML 5, a piece of code that will be needed
>  in many places and will process large amounts of data. It's written
>  entirely in Python.  Take a look at how much work has to be performed
>  per character.
> 
>  This is a good test for Python implementation bottlenecks.  Run
>  that tokenizer on HTML, and see where the time goes.
> 
>  ("It should be written in C" is not an acceptable answer.)

You could compile it with Cython though.  lxml took this route...

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From pm567426 at gmail.com  Sun Jul  5 03:38:30 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 00:38:30 -0700 (PDT)
Subject: How Python Implements "long integer"?
Message-ID: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>

Hello,
I'm reading about implementation of long ints in Python. I downloaded
the source code of CPython and will read the longobject.c, but from
where I should start reading this file? I mean which function is the
first?
Anyone can help?
Thanks

Pedram


From mail at microcorp.co.za  Sun Jul  5 04:12:54 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 5 Jul 2009 10:12:54 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <006201c9fd48$666d94e0$0d00a8c0@Hendrik>

"John Nagle" <nagle at ...ats.com> wrote:

> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code.  There's a comment in the code that it would be useful
> to run a few billion lines of HTML through an instrumented version
> of the parser to decide in which order the IF statements should be
> executed.  You shouldn't have to do that.

You do not have to implement a state machine in a case statement,
or in a series of if... elifs.

Python is not C.

Use a dispatch dict, and have each state return the next state.
Then you can use strings representing state names, and
everybody will be able to understand the code.

toy example, not tested, nor completed:

protocol = {"start":initialiser,"hunt":hunter,"classify":classifier,....other
states}

def state_machine():
    next_step = protocol["start"]()
    while True:
        next_step = protocol[next_step]()

Simple, and almost as fast as if you did the same thing
in assembler using pointers.

And each state will have a finite set of reasons to
either stay where its at, or move on.  Not a lot you
can do about that, but test for them one at a time.
But at least you will have split the problem up,
and you won't be doing irrelevant tests.

You can even do away with the dict, by having
each state return the actual next state routine:

next_state = protocol_initialiser()
while True:
    next_state = next_state()
    time.sleep(0.001)      # this prevents thrashing when monitoring real events

If you are using a gui, and you have access
to an after callback, then you can make a
ticking stutter thread to run some monitoring
machine in the background, using the same
"tell me what to do next" technique.

To take the timing thing further, you can do:

wait_time, next_state = protocol_initialiser()
while True:
    if wait_time:
        time.sleep(wait_time)
    wait_time, next_state = next_state()

This gives you control over busy-wait loops,
and lets you speed up when it is needed.

Python really is not C.

- Hendrik






From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 04:28:01 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 08:28:01 GMT
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <0260559c$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 20:15:11 -0700, John Nagle wrote:

> Paul Rubin wrote:
>> John Nagle <nagle at animats.com> writes:
>>>     A dictionary lookup (actually, several of them) for every
>>> input character is rather expensive. Tokenizers usually index into a
>>> table of character classes, then use the character class index in a
>>> switch statement.
>> 
>> Maybe you could use a regexp (and then have -two- problems...) to find
>> the token boundaries, then a dict to identify the actual token. Tables
>> of character classes seem a bit less attractive in the Unicode era than
>> in the old days.
> 
>     I want to see a regular expression that expresses the HTML 5 token
> parsing rules, including all the explicitly specified error handling.

Obviously the regex can't do the error handling. Nor should you expect a 
single regex to parse an entire HTML document. But you could (perhaps) 
use regexes to parse pieces of the document, as needed.

Have you investigated the pyparsing module? Unless you have some reason 
for avoiding it, for any complicated parsing job I'd turn to that before 
trying to roll your own.


>     Here's some actual code, from "tokenizer.py".  This is called once
> for each character in an HTML document, when in "data" state (outside a
> tag).  It's straightforward code, but look at all those dictionary
> lookups.

Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't 
see how a case statement would help you here: you're not dispatching on a 
value, but running through a series of tests until one passes. There are 
languages where you can write something like:

case:
    x > 0: process_positive(x)
    x < 0: process_negative(x)
    x == 0: process_zero(x)

but that's generally just syntactic sugar for the obvious if...elif... 
block. (Although clever compilers might recognise that it's the same x in 
each expression, and do something clever to optimize the code.)


Nor do I see why you were complaining about Python not having true 
constants. I don't see how that would help you... most of your explicit 
dict lookups are against string literals e.g. contentModelFlags["RCDATA"].

So while I feel your pain, I'm not sure I understand why you're blaming 
this on *Python*.


-- 
Steven


From stefan_ml at behnel.de  Sun Jul  5 04:41:58 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 10:41:58 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <4a506755$0$31333$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code.

Cython has a built-in optimisation that maps if-elif-else chains to C's
switch statement if they only test a single int/char variable, even when
you write things like "elif x in [1,5,9,12]". This works in Cython, because
we know that the comparison to a C int/char is side-effect free. It may not
always be side-effect free in Python, so this won't work in general. It
would be perfect for your case, though.

Stefan


From http  Sun Jul  5 04:58:13 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 01:58:13 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xws6nik0q.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't 
> see how a case statement would help you here: you're not dispatching on a 
> value, but running through a series of tests until one passes. 

A case statement switch(x):... into a bunch of constant case labels
would be able to use x as an index into a jump vector, and/or do an
unrolled logarithmic (bisection-like) search through the tests,
instead of a linear search.


From stefan_ml at behnel.de  Sun Jul  5 04:58:27 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 10:58:27 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a501a5e$0$1640$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
>    Here's some actual code, from "tokenizer.py".  This is called once
> for each character in an HTML document, when in "data" state (outside
> a tag).  It's straightforward code, but look at all those
> dictionary lookups.
> 
>     def dataState(self):
>         data = self.stream.char()
> 
>         # Keep a charbuffer to handle the escapeFlag
>         if self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):

Is the tuple

	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])

constant? If that is the case, I'd cut it out into a class member (or
module-local variable) first thing in the morning. And I'd definitely keep
the result of the "in" test in a local variable for reuse, seeing how many
times it's used in the rest of the code.

Writing inefficient code is not something to blame the language for.

Stefan


From stefan_ml at behnel.de  Sun Jul  5 05:04:33 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 11:04:33 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <4a506ca1$0$31344$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
> Paul Rubin wrote:
>> John Nagle <nagle at animats.com> writes:
>>> Python doesn't have a "switch" or "case" statement, and when
>>> you need a state machine with many states, that makes for painful,
>>> slow code.  ...
>>> There's a comment in the code that it would be useful
>>> to run a few billion lines of HTML through an instrumented version
>>> of the parser to decide in which order the IF statements should be
>>> executed.  You shouldn't have to do that.
>>
>> In that particular program it would probably be better to change those
>> if/elif/elif/else constructs to dictionary lookups.  I see the program
>> already does that for some large tables.
> 
>    A dictionary lookup (actually, several of them) for every
> input character is rather expensive.

Did you implement this and prove your claim in benchmarks? Taking a look at
the current implementation, I'm pretty sure a dict-based implementation
would outrun it in your first try.

Stefan


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 05:04:58 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 09:04:58 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
Message-ID: <02605e46$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 23:17:21 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> Certain people -- a tiny minority -- keep trying to argue that the
>> ability to say "if obj" for arbitrary objects is somehow a bad thing,
>> and their arguments seem to always boil down to: "If you write code
>> that assumes that only bools have a truth value, then surprising things
>> will happen because all objects have a truth value."
> 
> I'd put it under the general rubric of "explicit is better than
> implicit".  

"if x" is explicit. It's difficult to see how a branch could be anything 
other than explicit, but never mind.


> The language shouldn't do silly automatic typecasts all over
> the place.  

"if x" doesn't involve a typecast. Python doesn't have typecasts, except 
possibly for the special case of myobject.__class__ = Another_Class.

If you mean Python shouldn't do silly automatic type conversions all over 
the place, I absolutely agree with you! Fortunately, testing the truth 
value of an object isn't a silly automatic type conversion.


> Yes, it saves a few keystrokes to say "if x:" instead of "if
> len(x)==0:" or even "if bool(x):", 


It's not about saving keystrokes -- that's a furphy. It's about 
encapsulation. Objects are in a better position to recognise when they 
are "something" (true) or "nothing" (false) than you are.

Given an arbitrary object x, how do you know if it's something or 
nothing? In general, you can't tell -- but the object can, provided it's 
well written. (The conspicuous exception is iterators, but that's a 
special case.)

"if len(x) == 0" is wasteful. Perhaps I've passed you a list-like 
iterable instead of a list, and calculating the actual length is O(N). 
Why spend all that effort to find out the length of the object is 
59,872,819 only to throw that away? My object knows when it's empty, but 
instead you make foolish assumptions about the object and consequently 
write wastefully slow code.


> but if I program in a style where I
> like to think I know the type of something when I use it, I'd like the
> interpreter to let me know when I'm wrong instead of proceeding
> silently.

Oh come on now... that's a silly objection. If you want strongly-typed 
variables in Python, say so, don't pretend this is a failure of truth-
testing. If you write len(x)==0 Python doesn't complain if x is a dict 
instead of the list you were expecting. Why is it acceptable to duck-type 
len(x) but not truth-testing?


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 05:07:50 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 09:07:50 GMT
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<mailman.2631.1246781750.8015.python-list@python.org>
Message-ID: <02605ef2$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 10:12:54 +0200, Hendrik van Rooyen wrote:

> Python is not C.

John Nagle is an old hand at Python. He's perfectly aware of this, and 
I'm sure he's not trying to program C in Python.

I'm not entirely sure *what* he is doing, and hopefully he'll speak up 
and say, but whatever the problem is it's not going to be as simple as 
that.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 05:13:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 09:13:23 GMT
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
Message-ID: <0260603f$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 01:58:13 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't
>> see how a case statement would help you here: you're not dispatching on
>> a value, but running through a series of tests until one passes.
> 
> A case statement switch(x):... into a bunch of constant case labels
> would be able to use x as an index into a jump vector, and/or do an
> unrolled logarithmic (bisection-like) search through the tests, instead
> of a linear search.

Yes, I'm aware of that, but that's not what John's code is doing -- he's 
doing a series of if expr ... elif expr tests. I don't think a case 
statement can do much to optimize that.



-- 
Steven


From stef.mientki at gmail.com  Sun Jul  5 05:35:14 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 05 Jul 2009 11:35:14 +0200
Subject: Adding an object to the global namespace through " f_globals"
	is   that allowed ?
In-Reply-To: <h2hgbj$sp5$1@ger.gmane.org>
References: <4A4BC22D.70502@gmail.com> <h2hgbj$sp5$1@ger.gmane.org>
Message-ID: <4A5073D2.4010000@gmail.com>

Terry Reedy wrote:
> Stef Mientki wrote:
>> hello,
>>
>> I need to add an object's name to the global namespace.
>> The reason for this is to create an environment,
>> where you can add some kind of math environment,
>> where no need for Python knowledge is needed.
>>
>> The next statement works,
>> but I'm not sure if it will have any dramatical side effects,
>> other than overruling a possible object with the name A
>>
>> def some_function ( ...) :
>>      A = object ( ...)
>>      sys._getframe(1).f_globals [ Name ] = A
>
> global name
> name = A
>
> or is name is a string var
> globals()[name] = A
great, the last 2 lines works in most cases.
Now to get everything working correctly, I have to use both globals() 
and f_globals()
but everything seems to work perfect now.

thanks for all the hints.
cheers,
Stef



From http  Sun Jul  5 05:38:54 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 02:38:54 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xr5wvtqoh.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Yes, I'm aware of that, but that's not what John's code is doing -- he's 
> doing a series of if expr ... elif expr tests. I don't think a case 
> statement can do much to optimize that.

The series of tests is written that way because there is no case
statement available.  It is essentially switching on a bunch of
character constants and then doing some additional tests in each
branch.

It could be that using ord(c) as an index into a list of functions
might be faster than a dict lookup on c to get a function.  I think
John is hoping to avoid a function call and instead get an indexed
jump within the Python bytecode for the big function.


From stefan_ml at behnel.de  Sun Jul  5 05:41:18 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 11:41:18 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <4a50753e$0$31331$9b4e6d93@newsspool4.arcor-online.net>

Stefan Behnel wrote:
> John Nagle wrote:
>>    Here's some actual code, from "tokenizer.py".  This is called once
>> for each character in an HTML document, when in "data" state (outside
>> a tag).  It's straightforward code, but look at all those
>> dictionary lookups.
>>
>>     def dataState(self):
>>         data = self.stream.char()
>>
>>         # Keep a charbuffer to handle the escapeFlag
>>         if self.contentModelFlag in\
>>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
> 
> Is the tuple
> 
> 	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])
> 
> constant? If that is the case, I'd cut it out into a class member (or
> module-local variable) first thing in the morning.

Ah, and there's also this little trick to make it a (fast) local variable
in that method:

	def some_method(self, some_const=(1,2,3,4)):
	    ...

Stefan


From stefan_ml at behnel.de  Sun Jul  5 05:48:38 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 11:48:38 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xr5wvtqoh.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
Message-ID: <4a5076f8$0$31341$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Steven D'Aprano writes:
>> Yes, I'm aware of that, but that's not what John's code is doing -- he's 
>> doing a series of if expr ... elif expr tests. I don't think a case 
>> statement can do much to optimize that.
> 
> The series of tests is written that way because there is no case
> statement available.  It is essentially switching on a bunch of
> character constants and then doing some additional tests in each
> branch.

Although doing some of the tests first and then checking the input
conditionally might be faster here.

Another idea: You could exchange the methods whenever self.contentModelFlag
changes, i.e. you'd have a "dataState_CDATA", a "dataState_PCDATA" etc.


> It could be that using ord(c) as an index into a list of functions
> might be faster than a dict lookup on c to get a function.

Rather unlikely, given that calling "ord(c)" involves a dict lookup for
"ord". You might get away with the pre-initialised keywords trick, though.


> I think
> John is hoping to avoid a function call and instead get an indexed
> jump within the Python bytecode for the big function.

Hmm, yes, the actual code inside the conditionals is pretty short, so the
call overhead might hurt here.

Stefan


From http  Sun Jul  5 05:52:17 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 02:52:17 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7x7hyn5uem.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:
> >         # Keep a charbuffer to handle the escapeFlag
> >         if self.contentModelFlag in\
> >           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
> Is the tuple
> 	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])
> constant? If that is the case, I'd cut it out into a class member ...

I think the main issue for that function comes after that if statement.
There is a multi-way switch on a bunch of different possible character
values.  I do agree with you that the first "if" can also be optimized.


From ldo at geek-central.gen.new_zealand  Sun Jul  5 05:52:22 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 05 Jul 2009 21:52:22 +1200
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<h2or56$bko$1@lust.ihug.co.nz>
	<025ff4f1$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2pt4n$vs1$2@lust.ihug.co.nz>

In message <025ff4f1$0$20657$c3e8da3 at news.astraweb.com>, Steven D'Aprano wrote:

> On Sun, 05 Jul 2009 12:12:22 +1200, Lawrence D'Oliveiro wrote:
> 
>> In message <1beffd94-cfe6-4cf6-bd48-2ccac8637796 at j32g2000yqh.googlegroups.com>, ryles wrote:
>> 
>>>>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which
>>>>>> # iter() will do. Sorry guys!
>>> 
>>> Please don't let this happen to you too ;)
>> 
>> Strange. others have got told off for using "== None" instead of "is
>> None" <http://groups.google.co.nz/group/comp.lang.python/msg/a1f3170fa202af57>,
>> and yet it turns out Python itself does exactly the same thing.
> 
> That's not "strange", that's a bug.

It's not a bug, as Gabriel Genellina has pointed out.



From http  Sun Jul  5 05:54:23 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 02:54:23 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<4a5076f8$0$31341$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7x3a9b5ub4.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:
> > The series of tests is written that way because there is no case
> > statement available.  It is essentially switching on a bunch of
> > character constants and then doing some additional tests in each
> > branch.
> Although doing some of the tests first and then checking the input
> conditionally might be faster here.

That is essentially what happens.  There are a bunch of tests of the
form
   if data=='<' and [some other stuff]: ...

Because of short-circuit evaluation of "and", the additional tests
only happen once the character has been matched.


From ldo at geek-central.gen.new_zealand  Sun Jul  5 05:54:37 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 05 Jul 2009 21:54:37 +1200
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <h2pt8u$vs1$3@lust.ihug.co.nz>

In message <ddb65af7-8820-4a83-bc92-
c1d1c62d69fb at y17g2000yqn.googlegroups.com>, Klone wrote:

> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

I think you should be put on the management fast-track.



From dickinsm at gmail.com  Sun Jul  5 05:57:02 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Sun, 5 Jul 2009 02:57:02 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
Message-ID: <ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>

On Jul 5, 8:38?am, Pedram <pm567... at gmail.com> wrote:
> Hello,
> I'm reading about implementation of long ints in Python. I downloaded
> the source code of CPython and will read the longobject.c, but from
> where I should start reading this file? I mean which function is the
> first?

I don't really understand the question:  what do you mean by 'first'?
It might help if you tell us what your aims are.

In any case, you probably also want to look at the Include/
longintrepr.h and Include/longobject.h files.

Mark


From stefan_ml at behnel.de  Sun Jul  5 06:04:43 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 12:04:43 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7x3a9b5ub4.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<4a5076f8$0$31341$9b4e6d93@newsspool4.arcor-online.net>
	<7x3a9b5ub4.fsf@ruckus.brouhaha.com>
Message-ID: <4a507abb$0$31327$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Stefan Behnel writes:
>>> The series of tests is written that way because there is no case
>>> statement available.  It is essentially switching on a bunch of
>>> character constants and then doing some additional tests in each
>>> branch.
>> Although doing some of the tests first and then checking the input
>> conditionally might be faster here.
> 
> That is essentially what happens.  There are a bunch of tests of the
> form
>    if data=='<' and [some other stuff]: ...

That's what I meant. Some of the "other stuff" is redundant enough to do it
once at the beginning of the function (or even before entering the
function, by writing specialised methods), i.e. I'd (partially) reverse the
order of the "and" operands.

Stefan


From stefan_ml at behnel.de  Sun Jul  5 06:06:49 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 12:06:49 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7x7hyn5uem.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
	<7x7hyn5uem.fsf@ruckus.brouhaha.com>
Message-ID: <4a507b39$0$31327$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Stefan Behnel writes:
>>>         # Keep a charbuffer to handle the escapeFlag
>>>         if self.contentModelFlag in\
>>>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
>> Is the tuple
>> 	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])
>> constant? If that is the case, I'd cut it out into a class member ...
> 
> I think the main issue for that function comes after that if statement.
> There is a multi-way switch on a bunch of different possible character
> values.  I do agree with you that the first "if" can also be optimized.

You may notice that the creation of this exact tuple appears in almost all
if the conditionals of this method. So it is part of the bottleneck.

Stefan


From http  Sun Jul  5 06:08:16 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 03:08:16 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xy6r34f3j.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> > Yes, it saves a few keystrokes to say "if x:" instead of "if
> > len(x)==0:" or even "if bool(x):", 
> 
> It's not about saving keystrokes -- that's a furphy. It's about 
> encapsulation. Objects are in a better position to recognise when they 
> are "something" (true) or "nothing" (false) than you are.

I don't know what a furphy is, but I don't accept that "somethingness"
vs. "nothingness" is the same distinction as truth vs falsehood.  True
and False are values in a specific datatype (namely bool), not
abstract qualities of arbitrary data structures.  The idea that the
"if" statement selects between "somethingness" and "nothingness"
rather than between True and False is a bogus re-imagining of the
traditional function of an "if" statement and has been an endless
source of bugs in Python code.  Look how much confusion it causes here
in the newsgroup all the time.

> "if len(x) == 0" is wasteful. Perhaps I've passed you a list-like 
> iterable instead of a list, and calculating the actual length is O(N). 

That doesn't happen in any of Python's built-in container types.  I
could see some value to having a generic "is_empty" predicate on
containers though, to deal with this situation.  Your iterable could
support that predicate.  In fact maybe all iterables should support
that predicate.  They don't (and can't) all support "len".

> If you write len(x)==0 Python doesn't complain if x is a dict
> instead of the list you were expecting. Why is it acceptable to
> duck-type len(x) but not truth-testing?

I haven't seen the amount of bugs coming from generic "len" as from
something-vs-nothing confusion.


From http  Sun Jul  5 07:09:26 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 04:09:26 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
	<7x7hyn5uem.fsf@ruckus.brouhaha.com>
	<4a507b39$0$31327$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7xljn3bd3t.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:
> You may notice that the creation of this exact tuple appears in almost all
> if the conditionals of this method. So it is part of the bottleneck.

I don't think so.  The tuple is only created when the character has
already matched, and for the vast majority of the chars in the input
stream (ordinary text chars rather than html delimiters) none of them
match.


From stefan_ml at behnel.de  Sun Jul  5 07:23:23 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 13:23:23 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xljn3bd3t.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
	<7x7hyn5uem.fsf@ruckus.brouhaha.com>
	<4a507b39$0$31327$9b4e6d93@newsspool4.arcor-online.net>
	<7xljn3bd3t.fsf@ruckus.brouhaha.com>
Message-ID: <4a508d2c$0$31332$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Stefan Behnel writes:
>> You may notice that the creation of this exact tuple appears in almost all
>> if the conditionals of this method. So it is part of the bottleneck.
> 
> I don't think so.  The tuple is only created when the character has
> already matched, and for the vast majority of the chars in the input
> stream (ordinary text chars rather than html delimiters) none of them
> match.

Well, it's the second thing that happens when entering the method, it
happens several times later on when specific characters are matched, and it
also happens at the end when none of the special characters did match. So
it /is/ part of the bottleneck because the dict lookups, the tuple
creation, the "in" test and the tuple deallocation happen *twice* for
almost all characters in the stream.

Stefan


From 13139781969 at mymetropcs.com  Sun Jul  5 07:36:00 2009
From: 13139781969 at mymetropcs.com (13139781969 at mymetropcs.com)
Date: Sun, 5 Jul 2009 06:36:00 -0500
Subject: No subject
Message-ID: <1295065.145352441246808164305.JavaMail.mms@mms12.mms.metropcs.net>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090705/d84f24ad/attachment.html>
-------------- next part --------------
(Homer & Marge having sex with Bart Simpson)

From lie.1296 at gmail.com  Sun Jul  5 07:37:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 05 Jul 2009 11:37:49 GMT
Subject: question of style
In-Reply-To: <7xy6r34f3j.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
Message-ID: <hg04m.2790$ze1.2441@news-server.bigpond.net.au>

Paul Rubin wrote:
> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> "if len(x) == 0" is wasteful. Perhaps I've passed you a list-like 
>> iterable instead of a list, and calculating the actual length is O(N). 
> 
> That doesn't happen in any of Python's built-in container types.  I
> could see some value to having a generic "is_empty" predicate on
> containers though, to deal with this situation.  Your iterable could
> support that predicate.  In fact maybe all iterables should support
> that predicate.  They don't (and can't) all support "len".

That doesn't happen because all python's built-in container keep track
of its own length and are able to quickly determine its own length. But
outside builtins, certain iterables cannot determine its own length
quickly, e.g. iterators, but may have alternative ways to determine
whether itself is empty (through a "private" attributes). If you peek
through this private attribute, you're breaking encapsulation. Although
python is a language of consenting adults and doesn't really have a real
private, codes that breaks encapsulation is prone to bugs.

>>> Yes, it saves a few keystrokes to say "if x:" instead of "if
>>> len(x)==0:" or even "if bool(x):",
>> It's not about saving keystrokes -- that's a furphy. It's about
>> encapsulation. Objects are in a better position to recognise when
>> they are "something" (true) or "nothing" (false) than you are.
>
> I don't know what a furphy is, but I don't accept that "somethingness"
> vs. "nothingness" is the same distinction as truth vs falsehood.  True
> and False are values in a specific datatype (namely bool), not
> abstract qualities of arbitrary data structures.  The idea that the
> "if" statement selects between "somethingness" and "nothingness"
> rather than between True and False is a bogus re-imagining of the
> traditional function of an "if" statement and has been an endless
> source of bugs in Python code.  Look how much confusion it causes here
> in the newsgroup all the time.

Neither python's `if` nor `if` in formal logic is about testing True vs.
False. `if` in python and formal logic receives a statement. The
statement must be evaluatable to True or False, but does not have to be
True or False themselves. It just happens that True evaluates to True
and False evaluates to False. For example, the statement:

P := `e = 2.7182818284590451`
Q := `e = m*c**2`
----------------------------------
P -> Q

P -> Q evaluates to:
`e = 2.7182818284590451` -> `e = m*c**2`

Note that `e = 2.7182818284590451` is a statement, not a boolean value.
The truth value of `e = 2.7182818284590451` is determined by "calling"
(note the double quotes) `e = 2.7182818284590451`.statement_is_true(),
which when written in python syntax becomes: (e ==
2.7182818284590451).__bool__()

>> If you write len(x)==0 Python doesn't complain if x is a dict
>> instead of the list you were expecting. Why is it acceptable to
>> duck-type len(x) but not truth-testing?
> 
> I haven't seen the amount of bugs coming from generic "len" as from
> something-vs-nothing confusion.


From ptmcg at austin.rr.com  Sun Jul  5 07:41:27 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Sun, 5 Jul 2009 04:41:27 -0700 (PDT)
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<mailman.2631.1246781750.8015.python-list@python.org>
Message-ID: <7061fac4-954d-49e2-a03b-3ed8653a99f3@o6g2000yqj.googlegroups.com>

On Jul 5, 3:12 am, "Hendrik van Rooyen" <m... at microcorp.co.za> wrote:
>
> Use a dispatch dict, and have each state return the next state.
> Then you can use strings representing state names, and
> everybody will be able to understand the code.
>
> toy example, not tested, nor completed:
>
> protocol = {"start":initialiser,"hunt":hunter,"classify":classifier,....other
> states}
>
> def state_machine():
>     next_step = protocol["start"]()
>     while True:
>         next_step = protocol[next_step]()
>

I've just spent about an hour looking over this code, with a few
comments to inject to the thread here:

- To all those suggesting the OP convert to a dispatch table, be
assured that this code is well aware of this idiom.  It is used
HEAVILY at a macro level, picking through the various HTML states
(starting a tag, reading attributes, reading body, etc.).  There still
are a number of cascading if-elif's within some of these states, and
some of them *may* be candidates for further optimization.

- There is an underlying HTMLInputStream that seems to be doing some
unnecessary position bookkeeping (positionLine and positionCol).
Commenting this out increases my test speed by about 13%.  In my
ignorance, I may be removing some important behavior, but this does
not seem to be critical as I tested against a few megs of HTML
source.  Before blaming the tokenizer for everything, there may be
more performance to be wrung from the input stream processor.  For
that matter, I would guess that about 90% of all HTML files that this
code would process would easily fit in memory - in that case, the
stream processing (and all of the attendant "if I'm not at the end of
the current chunk" code) could be skipped/removed entirely.

- The HTMLInputStream's charsUntil code is an already-identified
bottleneck, and some re enhancements have been applied here to help
out.

- Run-time construction of tuple literals where the tuple members are
constants can be lifted out.  emitCurrentToken rebuilds this tuple
every time it is called (which is a lot!):

    if (token["type"] in (tokenTypes["StartTag"], tokenTypes
["EndTag"], tokenTypes["EmptyTag"])):

Move this tuple literal into a class constant (or if you can tolerate
it, a default method argument to gain LOAD_FAST benefits - sometimes
optimization isn't pretty).

- These kinds of optimizations are pretty small, and only make sense
if they are called frequently.  Tallying which states are called in my
test gives the following list in decreasing frequency.  Such a list
would help guide your further tuning efforts:

tagNameState	194848
dataState	182179
attributeNameState	116507
attributeValueDoubleQuotedState	114931
tagOpenState	105556
beforeAttributeNameState	58612
beforeAttributeValueState	58216
afterAttributeValueState	58083
closeTagOpenState	50547
entityDataState	1673
attributeValueSingleQuotedState	1098
commentEndDashState	372
markupDeclarationOpenState	370
commentEndState	364
commentStartState	362
commentState	362
selfClosingStartTagState	359
doctypePublicIdentifierDoubleQuotedState	291
doctypeSystemIdentifierDoubleQuotedState	247
attributeValueUnQuotedState	191
doctypeNameState	32
beforeDoctypePublicIdentifierState	16
afterDoctypePublicIdentifierState	14
afterDoctypeNameState	9
doctypeState	8
beforeDoctypeNameState	8
afterDoctypeSystemIdentifierState	6
afterAttributeNameState	5
commentStartDashState	2
bogusCommentState	2

For instance, I wouldn't bother doing much tuning of the
bogusCommentState.  Anything called fewer than 50,000 times in this
test doesn't look like it would be worth the trouble.


-- Paul

(Thanks to those who suggested pyparsing as an alternative, but I
think this code is already beyond pyparsing in a few respects.  For
one thing, this code works with an input stream, in order to process
large HTML files; pyparsing *only* works with an in-memory string.
This code can also take advantage of some performance short cuts,
knowing that it is parsing HTML; pyparsing's generic classes can't do
that.)


From stefan_ml at behnel.de  Sun Jul  5 07:52:07 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 13:52:07 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a501a5e$0$1640$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <4a5093e7$0$31338$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
>    Here's some actual code, from "tokenizer.py".  This is called once
> for each character in an HTML document, when in "data" state (outside
> a tag).  It's straightforward code, but look at all those
> dictionary lookups.
> 
>     def dataState(self):
>         data = self.stream.char()
> 
>         # Keep a charbuffer to handle the escapeFlag
>         if self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
>             if len(self.lastFourChars) == 4:
>                 self.lastFourChars.pop(0)
>             self.lastFourChars.append(data)
> 
>         # The rest of the logic
>         if data == "&" and self.contentModelFlag in\
>           (contentModelFlags["PCDATA"], contentModelFlags["RCDATA"]) and
> not\
>           self.escapeFlag:
>             self.state = self.states["entityData"]
>         elif data == "-" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and
> not\
>           self.escapeFlag and "".join(self.lastFourChars) == "<!--":
>             self.escapeFlag = True
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif (data == "<" and (self.contentModelFlag ==
> contentModelFlags["PCDATA"]
>                                or (self.contentModelFlag in
>                                    (contentModelFlags["CDATA"],
>                                     contentModelFlags["RCDATA"]) and
>                                    self.escapeFlag == False))):
>             self.state = self.states["tagOpen"]
>         elif data == ">" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and\
>           self.escapeFlag and "".join(self.lastFourChars)[1:] == "-->":
>             self.escapeFlag = False
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif data == EOF:
>             # Tokenization ends.
>             return False
>         elif data in spaceCharacters:
>             # Directly after emitting a token you switch back to the "data
>             # state". At that point spaceCharacters are important so
> they are
>             # emitted separately.
>             self.tokenQueue.append({"type": "SpaceCharacters", "data":
>               data + self.stream.charsUntil(spaceCharacters, True)})
>             # No need to update lastFourChars here, since the first
> space will
>             # have already broken any <!-- or --> sequences
>         else:
>             chars = self.stream.charsUntil(("&", "<", ">", "-"))
>             self.tokenQueue.append({"type": "Characters", "data":
>               data + chars})
>             self.lastFourChars += chars[-4:]
>             self.lastFourChars = self.lastFourChars[-4:]
>         return True

Giving this some more thought, I'd also try is to split the huge
if-elif-else block like this:

        if data in string_with_all_special_characters:
            if data == '&' ...:
                ...
        else:
            ...

So there are three things to improve:

- eliminate common subexpressions which you know are constant
- split the large conditional sequence as shown above
- use separate dataState() methods when inside and outside of CDATA/RCDATA
  blocks and (maybe) escaped blocks

Stefan


From pm567426 at gmail.com  Sun Jul  5 08:09:49 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 05:09:49 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
Message-ID: <68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com>

On Jul 5, 1:57?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 5, 8:38?am, Pedram <pm567... at gmail.com> wrote:
>
> > Hello,
> > I'm reading about implementation of long ints in Python. I downloaded
> > the source code of CPython and will read the longobject.c, but from
> > where I should start reading this file? I mean which function is the
> > first?
>
> I don't really understand the question: ?what do you mean by 'first'?
> It might help if you tell us what your aims are.
>
> In any case, you probably also want to look at the Include/
> longintrepr.h and Include/longobject.h files.
>
> Mark

Thanks for reply,
Sorry I can't explain too clear! I'm not English ;)
But I want to understand the implementation of long int object in
Python. How Python allocates memory and how it implements operations
for this object?
Although, I'm reading the source code (longobject.c and as you said,
longintrepr.h and longobject.h) but if you can help me, I really
appreciate that.

Pedram


From drobinow at gmail.com  Sun Jul  5 08:21:33 2009
From: drobinow at gmail.com (David Robinow)
Date: Sun, 5 Jul 2009 08:21:33 -0400
Subject: Is code duplication allowed in this instance?
In-Reply-To: <h2pt8u$vs1$3@lust.ihug.co.nz>
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
	<h2pt8u$vs1$3@lust.ihug.co.nz>
Message-ID: <4eb0089f0907050521n8d0f6eo271ec18c10040290@mail.gmail.com>

On Sun, Jul 5, 2009 at 5:54 AM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> In message <ddb65af7-8820-4a83-bc92-
> c1d1c62d69fb at y17g2000yqn.googlegroups.com>, Klone wrote:
>
>> So in this scenario is it OK to duplicate the algorithm to be tested
>> within the test codes or refactor the method such that it can be used
>> within test codes to verify itself(??).
>
> I think you should be put on the management fast-track.
 Heavens, no. He's too valuable as a managee.


From mjohnson at cfi.co.ug  Sun Jul  5 08:27:12 2009
From: mjohnson at cfi.co.ug (Johnson Mpeirwe)
Date: Sun, 5 Jul 2009 16:27:12 +0400
Subject: PSP Caching
In-Reply-To: <3e1c0979-fb6b-4d6e-80e5-a4af8d5fd96a@a36g2000yqc.googlegroups.com>
References: <mailman.2548.1246612730.8015.python-list@python.org>
	<3e1c0979-fb6b-4d6e-80e5-a4af8d5fd96a@a36g2000yqc.googlegroups.com>
Message-ID: <20090705122217.M97570@cfi.co.ug>

Thanks Simon,

I got around this behavior by adding "MaxRequestsPerChild  1" (default value
of this is 0) to my httpd.conf to limit the number of requests a child server
process will handle before it dies but I think it is important to keep it 0 in
production environment.

Regards,
Johnson

On Fri, 3 Jul 2009 10:44:52 -0700 (PDT), Simon Forman wrote
> On Jul 3, 5:18?am, Johnson Mpeirwe <mjohn... at cfi.co.ug> wrote:
> > Hello All,
> >
> > How do I stop caching of Python Server Pages (or whatever causes changes
> > in a page not to be noticed in a web browser)? I am new to developing
> > web applications in Python and after looking at implementations of PSP
> > like Spyce (which I believed introduces new unnecessary non-PSP syntax),
> > I decided to write my own PSP applications from scratch. When I modify a
> > file, I keep getting the old results until I intentionally introduce an
> > error (e.g parse error) and correct it after to have the changes
> > noticed. There's no proxy (I am working on a windows machine unplugged
> > from the network). I have Googled and no documents seem to talk about
> > this. Is there any particular mod_python directive I must set in my
> > Apache configuration to fix this?
> >
> > Any help will be highly appreciated.
> >
> > Johnson
> 
> I don't know much about caching with apache, but the answer mght be 
> on this page: http://httpd.apache.org/docs/2.2/caching.html
> 
> Meanwhile, couldn't you just send apache a restart signal when you
> modify your code?
> 
> HTH,
> ~Simon
> -- 
> http://mail.python.org/mailman/listinfo/python-list



From dickinsm at gmail.com  Sun Jul  5 09:04:11 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Sun, 5 Jul 2009 06:04:11 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com> 
	<68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com>
Message-ID: <249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>

On Jul 5, 1:09?pm, Pedram <pm567... at gmail.com> wrote:
> Thanks for reply,
> Sorry I can't explain too clear! I'm not English ;)

That's shocking.  Everyone should be English. :-)

> But I want to understand the implementation of long int object in
> Python. How Python allocates memory and how it implements operations
> for this object?

I'd pick one operation (e.g., addition), and trace through the
relevant functions in longobject.c.  Look at the long_as_number
table to see where to get started.

In the case of addition, that table shows that the nb_add slot is
given by long_add.  long_add does any necessary type conversions
(CONVERT_BINOP) and then calls either x_sub or x_add to do the real
work.
x_add calls _PyLong_New to allocate space for a new PyLongObject, then
does the usual digit-by-digit-with-carry addition.  Finally, it
normalizes
the result (removes any unnecessary zeros) and returns.

As far as memory allocation goes: almost all operations call
_PyLong_New at some point.  (Except in py3k, where it's a bit more
complicated because small integers are cached.)

If you have more specific questions I'll have a go at answering them.

Mark


From http  Sun Jul  5 09:12:25 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 06:12:25 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<025eaa4f$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7x1vovxohy.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> > I wouldn't say Python's None is terrible,...
> No, wait, I tell I lie... re.search() sometimes bites me, because 
> sometimes it returns None and sometimes it returns a matchobject and I 
> don't use re often enough to have good habits with it yet.

re is a common source of this type of bug but there are others.
> There are three natural approaches to (say) re.search() for dealing with 
> failure:
> 
> (1) return a sentinel value like None;
> (2) return a matchobject which tests False;
> (3) raise an exception.

4. Have re.search return a bool and possible matchobject separately:

   put_match_here = []
   if re.search(pat, s, target=put_match_here):
      do_something_with(put_match_here[0])

or alternatively (cleaner), have a new type of object which supports
search operations while self-updating with the match object:

   mt = re.match_target()
   ...
   if mt.search(pat, s):
      do_something_with(mt.match)
   if mt.search(pat2, s):
      do_another_thing_with(mt.match)
   ...

This is sort of inspired by what Perl does.  I often do something like
this because it makes it cleaner to chain a series of matches.


From mail at microcorp.co.za  Sun Jul  5 09:45:45 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 5 Jul 2009 15:45:45 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net><mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <00f201c9fd76$e61565a0$0d00a8c0@Hendrik>

"Steven D'Aprano" <steve at REMOVE-THIS-cy..e.com.au> wrote:

>On Sun, 05 Jul 2009 10:12:54 +0200, Hendrik van Rooyen wrote:
>
>> Python is not C.
>
>John Nagle is an old hand at Python. He's perfectly aware of this, and 
>I'm sure he's not trying to program C in Python.
>
>I'm not entirely sure *what* he is doing, and hopefully he'll speak up 
>and say, but whatever the problem is it's not going to be as simple as 
>that.

I am well aware that John is not a newbie.
He was complaining about Python's lack of a case statement
in the context of a state machine.

The point I was trying to make is that, if any state machine
is examined, then, if you examine any one state, the reasons
for leaving it ("state transitions") is always a subset of the
choices that _can_ be made.

So that drawing a circle round each state in a state diagram, 
and making a routine to examine the arrows leaving that circle,
and returning the destination point of the chosen arrow,
is a way of splitting the job up, and results in making only 
the relevant decisions at the time of their relevance.

This is in contrast to the classic C way of making one big
case statement to implement a finite state machine, which
gets its efficiency (if any) out of compiler optimisations
such as replacing a skip chain with a jump table.

I understand that it leads to a lot of what looks like 
boilerplate code, but he was looking for speed...

- Hendrik





From mail at microcorp.co.za  Sun Jul  5 10:03:05 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 5 Jul 2009 16:03:05 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net><7xvdm8thpo.fsf@ruckus.brouhaha.com><4a4fe6cb$0$1591$742ec2ed@news.sonic.net><7xfxdcqabg.fsf@ruckus.brouhaha.com><4a501a5e$0$1640$742ec2ed@news.sonic.net><0260559c$0$20657$c3e8da3@news.astraweb.com><7xws6nik0q.fsf@ruckus.brouhaha.com><0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
Message-ID: <00f901c9fd79$51d12160$0d00a8c0@Hendrik>

"Paul Rubin" <http://phr.cx at NOSPAM.invalid> wrote:

> The series of tests is written that way because there is no case
> statement available.  It is essentially switching on a bunch of
> character constants and then doing some additional tests in each
> branch.
> 
> It could be that using ord(c) as an index into a list of functions
> might be faster than a dict lookup on c to get a function.  I think
> John is hoping to avoid a function call and instead get an indexed
> jump within the Python bytecode for the big function.

I agree about the ord(c). However, avoiding the function call
is, I think, right now, in the realms of wishful thinking.

I cannot see how you could avoid a python function call - even if he
bites the bullet and implements my laborious scheme, he would still 
have to fetch the next character to test against, inside the current state.

So if it is the function calls that is slowing him down, I cannot
imagine a solution using less than one per character, in which
case he is screwed no matter what he does.

But wait - maybe if he passes an iterator around - the equivalent of
for char in input_stream...
Still no good though, unless the next call to the iterator is faster
than an ordinary python call.

- Hendrik





From pm567426 at gmail.com  Sun Jul  5 10:15:11 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 07:15:11 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com> 
	<68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com> 
	<249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>
Message-ID: <e0c38d40-187b-4765-83f4-96dea8251f8c@d4g2000yqa.googlegroups.com>

On Jul 5, 5:04?pm, Mark Dickinson <dicki... at gmail.com> wrote:

> That's shocking. ?Everyone should be English. :-)

Yes, I'm trying :)

> I'd pick one operation (e.g., addition), and trace through the
> relevant functions in longobject.c. ?Look at the long_as_number
> table to see where to get started.
>
> In the case of addition, that table shows that the nb_add slot is
> given by long_add. ?long_add does any necessary type conversions
> (CONVERT_BINOP) and then calls either x_sub or x_add to do the real
> work.
> x_add calls _PyLong_New to allocate space for a new PyLongObject, then
> does the usual digit-by-digit-with-carry addition. ?Finally, it
> normalizes
> the result (removes any unnecessary zeros) and returns.
>
> As far as memory allocation goes: almost all operations call
> _PyLong_New at some point. ?(Except in py3k, where it's a bit more
> complicated because small integers are cached.)

Oh, I didn't see long_as_number before. I'm reading it. That was very
helpful, thanks.

> If you have more specific questions I'll have a go at answering them.
>
> Mark

Thank you a million.
I will write your name in my "Specially thanks to" section of my
article (In font size 72) ;)

Pedram


From l.mastrodomenico at gmail.com  Sun Jul  5 10:25:31 2009
From: l.mastrodomenico at gmail.com (Lino Mastrodomenico)
Date: Sun, 5 Jul 2009 16:25:31 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <00f901c9fd79$51d12160$0d00a8c0@Hendrik>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<00f901c9fd79$51d12160$0d00a8c0@Hendrik>
Message-ID: <cc93256f0907050725o24d7fda0i19bad5b6d69cc877@mail.gmail.com>

2009/7/5 Hendrik van Rooyen <mail at microcorp.co.za>:
> I cannot see how you could avoid a python function call - even if he
> bites the bullet and implements my laborious scheme, he would still
> have to fetch the next character to test against, inside the current state.
>
> So if it is the function calls that is slowing him down, I cannot
> imagine a solution using less than one per character, in which
> case he is screwed no matter what he does.

A simple solution may be to read the whole input HTML file in a
string. This potentially requires lots of memory but I suspect that
the use case by far most common for this parser is to build a DOM (or
DOM-like) tree of the whole document. This tree usually requires much
more memory that the HTML source itself.

So, if the code duplication is acceptable, I suggest keeping this
implementation for cases where the input is extremely big *AND* the
whole program will work on it in "streaming", not just the parser
itself.

Then write a simpler and faster parser for the more common case when
the data is not huge *OR* the user will keep the whole document in
memory anyway (e.g. on a tree).

Also: profile, profile a lot. HTML pages are very strange beasts and
the bottlenecks may be in innocent-looking places!

-- 
Lino Mastrodomenico


From tn.pablo at gmail.com  Sun Jul  5 10:30:47 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sun, 5 Jul 2009 09:30:47 -0500
Subject: How Python Implements "long integer"?
In-Reply-To: <ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
Message-ID: <fdd00b510907050730r4390303eiaed973bd3408f03c@mail.gmail.com>

On Sun, Jul 5, 2009 at 04:57, Mark Dickinson<dickinsm at gmail.com> wrote:
> On Jul 5, 8:38?am, Pedram <pm567... at gmail.com> wrote:
>> Hello,
>> I'm reading about implementation of long ints in Python. I downloaded
>> the source code of CPython and will read the longobject.c, but from
>> where I should start reading this file? I mean which function is the
>> first?
>
> I don't really understand the question: ?what do you mean by 'first'?
> It might help if you tell us what your aims are.

I think he means the entry point, problem is that libraries have many.


-- 
Pablo Torres N.


From asm198 at gmail.com  Sun Jul  5 10:56:26 2009
From: asm198 at gmail.com (Icarus)
Date: Sun, 5 Jul 2009 07:56:26 -0700 (PDT)
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
	<h2n3d8$kvq$00$1@news.t-online.com>
	<c46b4e76-2c0d-49b5-bb97-c7e38934ac46@y7g2000yqa.googlegroups.com>
	<h2nvmi$9oh$03$1@news.t-online.com>
Message-ID: <39985616-d6b4-42f5-9db6-e7827f97c21d@24g2000yqm.googlegroups.com>

On Jul 4, 11:24?am, Peter Otten <__pete... at web.de> wrote:
> Icarus wrote:
> > On Jul 4, 3:21 am, Peter Otten <__pete... at web.de> wrote:
> >> Icarus wrote:
> >> > I'm working on a serial protocol analyzer in python. ?We have an
> >> > application written by someone else in MFC but we need something that
> >> > is cross platform. ?I intended to implement the GUI portion in Tkinter
> >> > but am having trouble.
>
> >> > The idea is that I will read messages from the serial port and output
> >> > them to a Tkinter Text object initially. ?Eventually it will have
> >> > other functionality but that's it for the short term. ?I've written
> >> > this little test app to experiment with putting things on the GUI via
> >> > a Queue which is polled by the Tkinter loop.
>
> >> > On some machines this code works fine and I get whatever I type in
> >> > displayed in the Text widget. ?On others I get errors like this as
> >> > soon as I start it running.
>
> >> > error in background error handler:
> >> > out of stack space (infinite loop?)
> >> > while executing
> >> > "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> >> > 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
> >> > while execu..."
>
> >> > I don't understand why on some machines it works exactly as expected
> >> > and on others it acts the same way Tkinter does when I call functions
> >> > directly from outside the Tkinter thread. ?Does anyone have any
> >> > suggestions? ?The full code as appended below. ?Thanks in advance.
>
> >> > [code]
>
> >> > import Queue
>
> >> > class functionQueue:
>
> >> > def __init__(self, root = None, timeout = 250):
>
> >> > self.functionQueue = Queue.Queue()
> >> > self.root = root
> >> > self.timeout = timeout
>
> >> > if(self.root):
> >> > self.pop_function(root)
>
> >> > def pop_function(self, root = None):
>
> >> > try:
> >> > funcArgList = self.functionQueue.get(block = False)
> >> > except Queue.Empty:
> >> > pass
> >> > else:
> >> > try:
> >> > funcArgList[0](*funcArgList[1])
> >> > except:
> >> > try:
> >> > print "Failed to call function", funcArgList[0]
> >> > except:
> >> > print "Failed to call function"
>
> >> > if(root):
> >> > root.after(self.timeout, lambda: self.pop_function
> >> > (self.root))
>
> >> > def add_function(self, function, argList):
>
> >> > try:
> >> > self.functionQueue.put([function, argList])
> >> > except:
> >> > pass
>
> >> > if( __name__ == '__main__'):
>
> >> > import Tkinter
> >> > import thread
>
> >> > text = Tkinter.Text()
> >> > text.pack()
>
> >> > myQueue = functionQueue(text, 50)
>
> >> > def gui_loop():
> >> > try:
> >> > text.mainloop()
> >> > except:
> >> > import os
> >> > os._exit(1)
>
> >> > thread.start_new_thread(text.mainloop, ())
>
> >> > while(True):
> >> > usrInput = raw_input()
>
> >> > if(usrInput == "-1"):
> >> > import os
> >> > os._exit(0)
>
> >> > myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> >> > myQueue.add_function(text.see, ['end'])
>
> >> > [/code]
>
> >> I can make it work over here by putting the UI into the main thread, as
> >> suggested byhttp://effbot.org/zone/tkinter-threads.htm:
>
> >> import Queue
> >> import Tkinter
> >> import threading
>
> >> class FunctionQueue:
> >> # unchanged
>
> >> def input_loop():
> >> while True:
> >> try:
> >> usrInput = raw_input()
> >> except EOFError:
> >> break
> >> myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> >> myQueue.add_function(text.see, ['end'])
> >> myQueue.add_function(text.quit, [])
>
> >> if __name__ == '__main__':
> >> text = Tkinter.Text()
> >> text.pack()
>
> >> myQueue = FunctionQueue(text, 50)
> >> threading.Thread(target=input_loop).start()
> >> text.mainloop()
>
> >> Peter
>
> > Peter, thanks for the suggestion. ?I tried your code exactly on my box
> > and I still get the same results. ?As soon as I run the script and
> > every time I click on the Text box I get tcl::Bgerror ... just like I
> > mentioned above. ?I'm fairly certain that I'm not calling Tkinter
> > functions from any other thread but it's acting as though I am as soon
> > as I create the input thread.
> > If I comment out the input loop thread everything is fine but of
> > course that's not terribly useful as a logging box.
>
> http://bugs.python.org/issue3835
>
> Could tcl have been built without thread support on the failing machines?
>
> Peter

You had it Peter.  I tried the "import pydoc pydoc.gui()" in the bug
report you referenced and the same thing described there occurred.
After recompiling tcl/tk with --threads-enabled and replacing the
slackware default packages with those everything is working as I
expected.  Thanks for the help.


From aahz at pythoncraft.com  Sun Jul  5 11:08:23 2009
From: aahz at pythoncraft.com (Aahz)
Date: 5 Jul 2009 08:08:23 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<mailman.2639.1246802753.8015.python-list@python.org>
Message-ID: <h2qfl7$k87$1@panix3.panix.com>

In article <mailman.2639.1246802753.8015.python-list at python.org>,
Hendrik van Rooyen <mail at microcorp.co.za> wrote:
>
>But wait - maybe if he passes an iterator around - the equivalent of
>for char in input_stream...  Still no good though, unless the next call
>to the iterator is faster than an ordinary python call.

Calls to iterators created by generators are indeed faster than an
ordinary Python call, because the stack frame is already mostly set up.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From nomail at thank.you  Sun Jul  5 11:26:21 2009
From: nomail at thank.you (jack catcher (nick))
Date: Sun, 05 Jul 2009 18:26:21 +0300
Subject: Python and webcam capture delay?
Message-ID: <dC34m.20648$vi5.6555@uutiset.elisa.fi>

Hi,

I'm thinking of using Python for capturing and showing live webcam 
stream simultaneously between two computers via local area network. 
Operating system is Windows. I'm going to begin with VideoCapture 
extension, no ideas about other implementation yet. Do you have any 
suggestions on how short delay I should hope to achieve in showing the 
video? This would be part of a psychological experiment, so I would need 
to deliver the video stream with a reasonable delay (say, below 100ms).


From serverin2000 at yahoo.com  Sun Jul  5 11:56:12 2009
From: serverin2000 at yahoo.com (RAM)
Date: Sun, 5 Jul 2009 08:56:12 -0700 (PDT)
Subject: generation of keyboard events
Message-ID: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>

Hi,

I need to start an external program and pass the keyboard events like
F1,Right arrow key etc to the program..I am trying to use the
subprocess module to invoke the external program. I am able to invoke
but not able to generate the keyboard events and pass them on to the
external progam. Please help me in this because I am a beginner.

regards
Sreerama V


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 12:00:03 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 16:00:03 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
Message-ID: <0260bf8d$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 03:08:16 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> > Yes, it saves a few keystrokes to say "if x:" instead of "if
>> > len(x)==0:" or even "if bool(x):",
>> 
>> It's not about saving keystrokes -- that's a furphy. It's about
>> encapsulation. Objects are in a better position to recognise when they
>> are "something" (true) or "nothing" (false) than you are.
> 
> I don't know what a furphy is, 

Is your Google broken? *wink*

http://en.wikipedia.org/wiki/Furphy


> but I don't accept that "somethingness"
> vs. "nothingness" is the same distinction as truth vs falsehood.

It's the distinction used by Python since the dawn of time. Python only 
grew a bool type a few versions back.


> True
> and False are values in a specific datatype (namely bool), not abstract
> qualities of arbitrary data structures.  

I'm not talking about the constants True and False (nouns), but about 
true and false values (adjectives).


> The idea that the "if"
> statement selects between "somethingness" and "nothingness" rather than
> between True and False is a bogus re-imagining of the traditional
> function of an "if" statement 

There's nothing bogus about it.

Some languages such as Pascal and Java require a special Boolean type for 
if-branches. Other languages, like Forth, C, Lisp and Ruby do not.

http://en.wikipedia.org/wiki/Boolean_data_type


> and has been an endless source of bugs in Python code.


I wonder why these "endless" bugs weren't important enough to be 
mentioned in the rationale to PEP 285:

http://www.python.org/dev/peps/pep-0285/

You'd think something as vital as "if x Considered Harmful" would have 
made it into the PEP, but no. Instead Guido *explicitly* stated that he 
had no intention of forcing `if` to require a bool, describing `if x` as 
the "correct form" and calling scrapping such a feature as "crippling the 
language".

 
> Look how much confusion it causes here in the newsgroup all the time.

The only confusion is that you're causing me. Would you care to link to 
some?



>> "if len(x) == 0" is wasteful. Perhaps I've passed you a list-like
>> iterable instead of a list, and calculating the actual length is O(N).
> 
> That doesn't happen in any of Python's built-in container types.

And if they were the only types possible in Python, that might be 
relevant.


> I
> could see some value to having a generic "is_empty" predicate on
> containers though, to deal with this situation.

We have that already. It's spelled __bool__ or __nonzero__, and it 
applies to any object, not just containers.


> Your iterable could
> support that predicate.  In fact maybe all iterables should support that
> predicate.  They don't (and can't) all support "len".

Iterators are a special case, because in general they can't tell if 
they're exhausted until they try to yield a value.


>> If you write len(x)==0 Python doesn't complain if x is a dict instead
>> of the list you were expecting. Why is it acceptable to duck-type
>> len(x) but not truth-testing?
> 
> I haven't seen the amount of bugs coming from generic "len" as from
> something-vs-nothing confusion.

Again with these alleged bugs.



-- 
Steven


From pm567426 at gmail.com  Sun Jul  5 12:01:30 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 09:01:30 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
Message-ID: <6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com>

Hello again,
This time I have a simple C question!
As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
found PyObject_NEW_VAR in objimpl.h header file. But I can't
understand the last line :( Here's the code:

#define PyObject_NEW_VAR(type, typeobj, n) \
( (type *) PyObject_InitVar( \
      (PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
(n)) ),\
      (typeobj), (n)) )

I know this will replace the PyObject_New_VAR(type, typeobj, n)
everywhere in the code and but I can't understand the last line, which
is just 'typeobj' and 'n'! What do they do? Are they make any sense in
allocation process?


From aahz at pythoncraft.com  Sun Jul  5 12:12:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 5 Jul 2009 09:12:19 -0700
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com>
Message-ID: <h2qjd3$ji7$1@panix3.panix.com>

In article <6f6be2b9-49f4-4db0-9c21-52062d8ea3df at l31g2000yqb.googlegroups.com>,
Pedram  <pm567426 at gmail.com> wrote:
>
>This time I have a simple C question!
>As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
>found PyObject_NEW_VAR in objimpl.h header file. But I can't
>understand the last line :( Here's the code:
>
>#define PyObject_NEW_VAR(type, typeobj, n) \
>( (type *) PyObject_InitVar( \
>      (PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
>(n)) ),\
>      (typeobj), (n)) )
>
>I know this will replace the PyObject_New_VAR(type, typeobj, n)
>everywhere in the code and but I can't understand the last line, which
>is just 'typeobj' and 'n'! What do they do? Are they make any sense in
>allocation process?

Look in the code to find out what PyObject_InitVar() does -- and, more
importantly, what its signature is.  The clue you're missing is the
trailing backslash on the third line, but that should not be required if
you're using an editor that shows you matching parentheses.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From usernet at ilthio.net  Sun Jul  5 12:12:37 2009
From: usernet at ilthio.net (Tim Harig)
Date: Sun, 05 Jul 2009 16:12:37 GMT
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
Message-ID: <Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>

On 2009-07-05, RAM <serverin2000 at yahoo.com> wrote:
> I need to start an external program and pass the keyboard events like
> F1,Right arrow key etc to the program..I am trying to use the
> subprocess module to invoke the external program. I am able to invoke
> but not able to generate the keyboard events and pass them on to the

catb.org/esr/faqs/smart-questions.html

You have told us nothing about the environment where you are trying to
accomplish this.  GUI, CLI, Unix, Windows, etc? So I suggest that you
checkout the curses getch functions.  You can find them in the standard
library documentation at http://docs.python.org.  You should also reference
documentation for the C version in your systems man pages.


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 12:13:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 16:13:30 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
	<hg04m.2790$ze1.2441@news-server.bigpond.net.au>
Message-ID: <0260c2b4$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 11:37:49 +0000, Lie Ryan wrote:

> Neither python's `if` nor `if` in formal logic is about testing True vs.
> False. `if` in python and formal logic receives a statement. The
> statement must be evaluatable to True or False, but does not have to be
> True or False themselves. It just happens that True evaluates to True
> and False evaluates to False.

I think your explanation is a little confused, or at least confusing.

`if` implements a two-way branch. Some languages, like Pascal and Java, 
requires the switch value to take one of two specific enumerable values 
conventionally spelled TRUE and FALSE (modulo variations in case).

Other languages don't require specific enumerable values, and instead 
accept (e.g.) any integer, or any object, with rules for how to interpret 
such values in such a context. Forth, for example, branches according to 
whether the word on the stack is zero or non-zero: "nothing" or 
"something". Lisp branches according to empty list or non-empty list: 
"nothing" or "something" again.

Other languages, like Ruby, have less intuitive rules. That's their 
problem.



-- 
Steven


From emile at fenx.com  Sun Jul  5 12:19:48 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 05 Jul 2009 09:19:48 -0700
Subject: generation of keyboard events
In-Reply-To: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
Message-ID: <h2qjr9$6k3$1@ger.gmane.org>

On 7/5/2009 8:56 AM RAM said...
> Hi,
> 
> I need to start an external program and pass the keyboard events like
> F1,Right arrow key etc to the program..I am trying to use the
> subprocess module to invoke the external program. I am able to invoke
> but not able to generate the keyboard events and pass them on to the
> external progam.

If you're on *nix, search for python and expect and you'll find 
something based apps -- I'm not sure what you do for GUIs. On windows, 
I'm sure there are ways of doing this with the win32 extensions, but I 
commonly use msched from www.mjtnet.com.  I create msched scripts from 
within python and use subprocess to invoke msched and execute the python 
generated script.

HTH,

Emile


> Please help me in this because I am a beginner.
> 
> regards
> Sreerama V



From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 12:20:32 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 16:20:32 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<025eaa4f$0$20657$c3e8da3@news.astraweb.com>
	<7x1vovxohy.fsf@ruckus.brouhaha.com>
Message-ID: <0260c45a$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 06:12:25 -0700, Paul Rubin wrote:

>> There are three natural approaches to (say) re.search() for dealing
>> with failure:
>> 
>> (1) return a sentinel value like None; (2) return a matchobject which
>> tests False; (3) raise an exception.
> 
> 4. Have re.search return a bool and possible matchobject separately:
> 
>    put_match_here = []
>    if re.search(pat, s, target=put_match_here):
>       do_something_with(put_match_here[0])

Wow. I never for the life of me thought I'd see an experienced Python 
programmer re-implement Pascal's VAR parameters.

That is... hideous. Returning a (flag, matchobject) tuple is the height 
of beauty in comparison.



-- 
Steven


From pm567426 at gmail.com  Sun Jul  5 12:32:41 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 09:32:41 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com> 
	<h2qjd3$ji7$1@panix3.panix.com>
Message-ID: <179f64f8-6528-4953-88b1-4096d5907cbe@p29g2000yqh.googlegroups.com>

On Jul 5, 8:12?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <6f6be2b9-49f4-4db0-9c21-52062d8ea... at l31g2000yqb.googlegroups.com>,
>
>
>
> Pedram ?<pm567... at gmail.com> wrote:
>
> >This time I have a simple C question!
> >As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
> >found PyObject_NEW_VAR in objimpl.h header file. But I can't
> >understand the last line :( Here's the code:
>
> >#define PyObject_NEW_VAR(type, typeobj, n) \
> >( (type *) PyObject_InitVar( \
> > ? ? ?(PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
> >(n)) ),\
> > ? ? ?(typeobj), (n)) )
>
> >I know this will replace the PyObject_New_VAR(type, typeobj, n)
> >everywhere in the code and but I can't understand the last line, which
> >is just 'typeobj' and 'n'! What do they do? Are they make any sense in
> >allocation process?
>
> Look in the code to find out what PyObject_InitVar() does -- and, more
> importantly, what its signature is. ?The clue you're missing is the
> trailing backslash on the third line, but that should not be required if
> you're using an editor that shows you matching parentheses.
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "as long as we like the same operating system, things are cool." --piranha

No, they wrapped the 3rd line!

I'll show you the code in picture below:
http://lh3.ggpht.com/_35nHfALLgC4/SlDVMEl6oOI/AAAAAAAAAKg/vPWA1gttvHM/s640/Screenshot.png

As you can see the PyObject_MALLOC has nothing to do with typeobj and
n in line 4.


From pm567426 at gmail.com  Sun Jul  5 12:34:37 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 09:34:37 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com> 
	<h2qjd3$ji7$1@panix3.panix.com>
	<179f64f8-6528-4953-88b1-4096d5907cbe@p29g2000yqh.googlegroups.com>
Message-ID: <5a0b1063-ae2b-4229-b040-4904b4d01077@b15g2000yqd.googlegroups.com>

On Jul 5, 8:32?pm, Pedram <pm567... at gmail.com> wrote:
> On Jul 5, 8:12?pm, a... at pythoncraft.com (Aahz) wrote:
>
>
>
> > In article <6f6be2b9-49f4-4db0-9c21-52062d8ea... at l31g2000yqb.googlegroups.com>,
>
> > Pedram ?<pm567... at gmail.com> wrote:
>
> > >This time I have a simple C question!
> > >As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
> > >found PyObject_NEW_VAR in objimpl.h header file. But I can't
> > >understand the last line :( Here's the code:
>
> > >#define PyObject_NEW_VAR(type, typeobj, n) \
> > >( (type *) PyObject_InitVar( \
> > > ? ? ?(PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
> > >(n)) ),\
> > > ? ? ?(typeobj), (n)) )
>
> > >I know this will replace the PyObject_New_VAR(type, typeobj, n)
> > >everywhere in the code and but I can't understand the last line, which
> > >is just 'typeobj' and 'n'! What do they do? Are they make any sense in
> > >allocation process?
>
> > Look in the code to find out what PyObject_InitVar() does -- and, more
> > importantly, what its signature is. ?The clue you're missing is the
> > trailing backslash on the third line, but that should not be required if
> > you're using an editor that shows you matching parentheses.
> > --
> > Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> > "as long as we like the same operating system, things are cool." --piranha
>
> No, they wrapped the 3rd line!
>
> I'll show you the code in picture below:http://lh3.ggpht.com/_35nHfALLgC4/SlDVMEl6oOI/AAAAAAAAAKg/vPWA1gttvHM...
>
> As you can see the PyObject_MALLOC has nothing to do with typeobj and
> n in line 4.

Oooooh! What a mistake! I got it! they're Py_Object_InitVar
parameters.
Sorry and Thanks!


From lie.1296 at gmail.com  Sun Jul  5 12:43:35 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 05 Jul 2009 16:43:35 GMT
Subject: question of style
In-Reply-To: <0260c2b4$0$20657$c3e8da3@news.astraweb.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<025ff51b$0$20657$c3e8da3@news.astraweb.com>	<7xfxdbk61a.fsf@ruckus.brouhaha.com>	<02605e46$0$20657$c3e8da3@news.astraweb.com>	<7xy6r34f3j.fsf@ruckus.brouhaha.com>	<hg04m.2790$ze1.2441@news-server.bigpond.net.au>
	<0260c2b4$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <XK44m.2824$ze1.1582@news-server.bigpond.net.au>

Steven D'Aprano wrote:
> On Sun, 05 Jul 2009 11:37:49 +0000, Lie Ryan wrote:
> 
>> Neither python's `if` nor `if` in formal logic is about testing True vs.
>> False. `if` in python and formal logic receives a statement. The
>> statement must be evaluatable to True or False, but does not have to be
>> True or False themselves. It just happens that True evaluates to True
>> and False evaluates to False.
> 
> I think your explanation is a little confused, or at least confusing.

Indeed, partially because I said "statement" when I really meant
"expression".

> Other languages don't require specific enumerable values, and instead 
> accept (e.g.) any integer, or any object, with rules for how to interpret 
> such values in such a context. 

That was what I was wanting to say, except that I stretched that to
formal logic (mathematical logic). Even in formal logic `if` receives
any arbitrary expression that can be -- according to certain rules --
interpreted as True or False (i.e. the expressions themselves are not
required to be a boolean value).

The conclusion is python's `if` does not deviate from `if`'s semantic in
mathematical sense.


From piet at cs.uu.nl  Sun Jul  5 13:28:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 05 Jul 2009 19:28:35 +0200
Subject: Determining if a function is a method of a class within
	a	decorator
References: <4A4963E9.30202@ilm.com> <h2bpu2$ki$1@ger.gmane.org>
	<mailman.2349.1246327265.8015.python-list@python.org>
Message-ID: <m2y6r3doos.fsf@cs.uu.nl>

>>>>> David Hirschfield <davidh at ilm.com> (DH) wrote:

>DH> Yeah, it definitely seems like having two separate decorators is the
>DH> solution. But the strange thing is that I found this snippet after some
>DH> deep googling, that seems to do something *like* what I want, though I
>DH> don't understand the descriptor stuff nearly well enough to get what's
>DH> happening:

>DH> http://stackoverflow.com/questions/306130/python-decorator-makes-function-forget-that-it-belongs-to-a-class

>DH> answer number 3, by ianb. It seems to indicate there's a way to introspect
>DH> and determine the class that the function is going to be bound to...but I
>DH> don't get it, and I'm not sure it's applicable to my case.

>DH> I'd love an explanation of what is going on in that setup, and if it isn't
>DH> usable for my situation, why not?

What that example does is not getting the name of the class in the
decorator, but in the bound method that is the result of the decorator
when that method is called. This is just done by asking for the class of
the self parameter. Actually they even don't do that in that example but
it could have been done. Note also that there is an error in the code:
keyargs should be kw.

There is also something special in that code: it uses the descriptor
protocol. This is necessary for a method. The descriptor protocol for
methods defines a __get__ method that transforms the unbound method into
a bound method. That code uses this to decorate the generated bound method
object instead of decorating the unbound method.

A side effect of doing the class detection at call time is that you get
the name of the subclass if you use the method on an instance of the
subclass, not the name of the class that the method was defined in:

class D(C):
     pass

D().f(1, 2) will talk about class D, not class C.

So if you would like to do something special for bound methods the
__get__ might be the proper place to do it.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From a0046088 at airmail.net  Sun Jul  5 14:20:26 2009
From: a0046088 at airmail.net (wwwayne)
Date: Sun, 05 Jul 2009 12:20:26 -0600
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
Message-ID: <3in15557eu33n494hh3lvmcnssujl2ueds@4ax.com>

On Fri, 03 Jul 2009 14:34:58 GMT, Alan G Isaac <alan.isaac at gmail.com>
wrote:

>On 7/3/2009 10:05 AM kj apparently wrote:

=== 8< ===

>2.
>from scipy.optimize import bisect
>def _binary_search(lo, hi, func, target, epsilon):
>    def f(x): return func(x) - target
>    return bisect(f, lo, high, xtol=epsilon)
>
>3. If you don't want to use SciPy (why?), have them
>implement http://en.wikipedia.org/wiki/Bisection_method#Pseudo-code
>to produce their own `bisect` function.

Of course this isn't really pseudo-code, it's VB code with quite poor
comments: 

    'Bisection Method
 
   'Start loop
    Do While (abs(right - left) > 2*epsilon)
 
      'Calculate midpoint of domain
      midpoint = (right + left) / 2
 
      'Find f(midpoint)
      If ((f(left) * f(midpoint)) > 0) Then
        'Throw away left half
        left = midpoint
      Else
        'Throw away right half
        right = midpoint
      End If
    Loop
    Return (right + left) / 2

and even just throwing away the VB code and leaving the comments does
not give a good algorithm:

    'Bisection Method
 
    'Start loop
 
      'Calculate midpoint of domain
 
      'Find f(midpoint)

        'Throw away left half

        'Throw away right half

A much  better approach to teaching introductory programming in any
language at almost any level is to incorporate some "top down problem
solving", including writing a method of solution (algorithm) in some
reasonably well-defined pseudo-code that can be easily elaborated and
translated into one's target language (and, peferably, some
reasonable-sized subset of related languages). This pseudo-code should
then become comments (or equivalent) for the students to convert to
real code, as in:

Algorithm bisect (f, left, right, epsilon):

# Bisection Method to find a root of a real continuous function f(x):
#    Assume f(x) changes sign between f(left) and f(right) and
#       we want a value not further than epsilon from a real root.
#    Begin with the domain left...right.

# While the absolute value of (left - right) exceeds 2*epsilon:

	# Calculate the midpoint, mid,  of the domain.

	# If the product of f(left) and f(mid) is positive:

		# Set left to mid;

	# Otherwise:

		# Set right to mid.

# Return the midpoint of left...right.

===
And adapting this approach to kj's case is straightforward.

Of course, what consitutes a suitable vocabulary and syntax for an
algorithm pseudo-code language depends upon the target language(s),
the tastes of the instructor, and the point in the lesson or course.
My choice is for python+COBOL (as above) initially, soon incorporating
the usual arithmetic and relational operators (and how soon and how
many at once depends upon the level of the students: for an
introductory university/college course in Computer Science or
equivalent, where everyone should have a reasonable background in
mathemtics notation as a prerequisite, this should be very soon and
quite fast), arrays and subscripting, etc.

But if we were to write this algorithm or kj's in python-like
pseudo-code it would already *be* python codeor very close to
it--which is why we should teach intorductory programming in python.
Very soon students would be writing algorithms that required very
little elaboration to be programs.

But without including suitable problem solving and psudo-code
algorithm writing there will soon come a time or an example where
students are trying to think in code instead of in their natural
language and don't have the experience and repertoire to be able to do
that well.

I hope that's not too pedantic or AR?

wayne

>hth,
>Alan Isaac


From dotancohen at gmail.com  Sun Jul  5 14:32:56 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Sun, 5 Jul 2009 21:32:56 +0300
Subject: A C++ user's introduction to Python: a really good read
Message-ID: <880dece00907051132p117ca7e0sf5774d1eb5014c64@mail.gmail.com>

Here is a C++ KDE programer's take on Python:
http://majewsky.wordpress.com/2009/07/04/python-experiences-or-why-i-like-c-more/

Good read.

-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From nick.m.daly at gmail.com  Sun Jul  5 14:48:06 2009
From: nick.m.daly at gmail.com (Nick Daly)
Date: Sun, 5 Jul 2009 13:48:06 -0500
Subject: Method to separate unit-test methods and data?
In-Reply-To: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
References: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
Message-ID: <be8f57070907051148x52ee305ch905c79bb0d59d983@mail.gmail.com>

Hi,

I was wondering if it's possible / if there are any simple methods
known of storing unit-test functions and their data in separate files?

Perhaps this is a strange request, but it does an excellent job of
modularizing code. ?As far as revision control goes, it makes it
easier to discern between new or changed test cases, and changes in
the test data.

I've worked through this idea a bit and actually have a nearly working
model. ?For example, when testing a class, I have a test module, which
contains a class for testing each method of the class. ?This allows me
to generalize each method's parameters into each class, which can then
be overridden by the config file's data, something like as follows
(with a really arbitrary example, Python 2.5 code):


Demo code (midpoint.py):
=======================

class Midpoint(object):

? ?def __init__(self, a, b):
? ? ? ?self.a = a
? ? ? ?self.b = b

? ?def mid():
? ? ? ?return (self.a + self.b) / 2.0

? ?def sum()
? ? ? ?return (self.a + self.b)



Testing Code (test_Midpoint.py):
===============================

import unittest
import midpoint
import sys, ConfigParser as configparser


# set up the config file that overrides each class's data
config = configparser.SafeConfigParser()
config.read(sys.argv[0])


class test_Midpoint_mid(unittest.TestCase):
? ?def __init__(self):

? ? ? ?# default testing values
? ? ? ?self.none_values = ((None, 1),
? ? ? ? ? ? ? ? ? ? ? ? ? ?(0, None))

? ? ? ?# override the default values with the config file values
? ? ? ?for key, value in config.items(self.__class__.__name__):
? ? ? ? ? ?if value:
? ? ? ? ? ? ? ?setattr(self, key, value)


? ?# a few tests of the method
? ?def test_rejectNone(self):
? ? ? ?for tests in self.none_values:
? ? ? ? ? ?self.assertRaises(TypeError,
? ? ? ? ? ? ? ?midpoint.Midpoint(tests[0], tests[1]).mid)

# and repeat the concept for class test_Midpoint_sum



Config Code (test_Midpoint.cfg):
==============================

# override the default values of the test class's members

[test_Midpoint_mid]
none_values = ((-1, None),
? ? ? ? ? ? ? (None, -12.8))



What I haven't yet figured out how to do though, is properly override
the default class member values with values from the config file. ?The
config file's data is loaded as a string instead of as a list, as I'd
want. ?This causes all the tests to fail, as while none_values needs
to be interpreted as a list, it is instead understood as:

" ((-1, None),\n ? ? ? ? ? ? ? (None, -12.8))"

Does anyone have any solutions for these problems? ?First, is there a
known and simple way to separate unit-test data and methods into
separate files? ?Secondly, if not, is there a simple way to convert
strings into other base types, like lists, dictionaries, and so forth?
Or, am I going to have to write my own list-parsing methods? ?Would
pickling help? ?I haven't yet had a chance to look into if or how that
would work... ?If there's anything else I can clarify about this
request, feel free to let me know.

Thanks for any help you can provide,
Nick


From maymunbeyin at gmail.com  Sun Jul  5 14:59:01 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 11:59:01 -0700 (PDT)
Subject: Creating alot of class instances?
Message-ID: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>

Hi

I am new to Python classes and trying to figure out this particular
issue here. I will need to create instances of a class. But at the
moment I do not know how many instances I will end up having, in every
case it might be different. Most of the documents I read makes this
simpl class-student analogy to explain python classes which is fine.
But in those examples the number and the names of the instances were
known and limited.

I will be querying some data and create class instances based on the
data I gather. But the problem as I mentioned is that I do not know
the names and the number of the end class instances. They will be
based on the content of the data. So how can I create class instances
within a loop and when the loop is done how can I figure out the list
of instances via class membership?  I can track the names by
introducing another list but I want to understand the class side of
things.

The solution might be dead simple but I just cannot figure out at the
moment.

For example this is what I need in the simplest form

class myclass():
 def __init__(self,name):
 self.name=name

for count,data in enumerate(some list):
  instance_count=myclass()
  instance_count.name=data

print instances


thanks





From tjreedy at udel.edu  Sun Jul  5 15:09:33 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 05 Jul 2009 15:09:33 -0400
Subject: question of style
In-Reply-To: <7xy6r34f3j.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<025ff51b$0$20657$c3e8da3@news.astraweb.com>	<7xfxdbk61a.fsf@ruckus.brouhaha.com>	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
Message-ID: <h2qtpe$v2f$1@ger.gmane.org>

Paul Rubin wrote:

> I don't know what a furphy is, but I don't accept that "somethingness"
> vs. "nothingness" is the same distinction as truth vs falsehood.  True
> and False are values in a specific datatype (namely bool), not
> abstract qualities of arbitrary data structures.  The idea that the
> "if" statement selects between "somethingness" and "nothingness"
> rather than between True and False is a bogus re-imagining of the
> traditional function of an "if" statement and has been an endless
> source of bugs in Python code.  Look how much confusion it causes here
> in the newsgroup all the time.

You appear to be confusing a specific interpretation of an abstraction 
with the abstraction itself. Or perhaps better, you seem to be confusing 
a specific example of a general process with the general process.

A boolean variable is a variable that is in one of two states -- a 
binary variable -- a variable that carries one bit of information. The 
two states are the marked state and the unmarked or default state. Which 
is to say, when we draw a distinction to distinguish two states, we mark 
one of them to distinguish one from the other. The if statement tests 
whether an object is in the marked state (or not).

Truth and falsity of propositions are one possible interpretation of 
marked and unmarked, giving us propositional logic.  But they are only 
one of many. So are in and out of a particular class and member or not 
of a set or subclass or not of a set, giving us class and set logic. So 
are closed and open, said of gates or switches, or on and off, giving us 
switching logic. So are non-zero and zero, said of numbers. Or done and 
not done, said of an algorithmic process.

Counts 0 and 1, and their representations '0' and '1', taken in 
themselves, are as good as any distinct pair as a pair of labels for the 
two distinct states. They have some computational advantages, including 
making it easy to count the number of objects in a collection in the 
marked state (and, given the total number, the number in the unmarked 
state). They have one disadvantage, though. If I say 'x = 1', do I mean 
1 versus 0 or 1 versus all possible ints? Similarly, If 'print(x)' 
prints 1, does it mean 1 versus 0 or 1 versus all other ints? 
Recognizing this, Guido decided to subclass them and give them alternate 
names. He could have chosen 'Marked' and 'Unmarked', or any of several 
other pairs, but did choose the conventional 'True' and 'False', 
referring to the common propositional interpretation. However, he 
specifically disclaimed any intention to restrict 'if' to testing 
specific logic propositions, as opposed to the general proposition 
'object is in the marked state'.

Terry Jan Reedy



From andreengels at gmail.com  Sun Jul  5 15:20:38 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sun, 5 Jul 2009 21:20:38 +0200
Subject: Creating alot of class instances?
In-Reply-To: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
Message-ID: <6faf39c90907051220o5b2adebbnae1136d987209a5a@mail.gmail.com>

On 7/5/09, kk <maymunbeyin at gmail.com> wrote:

>  I am new to Python classes and trying to figure out this particular
>  issue here. I will need to create instances of a class. But at the
>  moment I do not know how many instances I will end up having, in every
>  case it might be different. Most of the documents I read makes this
>  simpl class-student analogy to explain python classes which is fine.
>  But in those examples the number and the names of the instances were
>  known and limited

That's no problem. The only limit to the number of instances of a
class you can create is your memory - and not even that if you don't
need to 'keep' the instances.

>  I will be querying some data and create class instances based on the
>  data I gather. But the problem as I mentioned is that I do not know
>  the names and the number of the end class instances. They will be
>  based on the content of the data. So how can I create class instances
>  within a loop and when the loop is done how can I figure out the list
>  of instances via class membership?  I can track the names by
>  introducing another list but I want to understand the class side of
>  things.
>
>  The solution might be dead simple but I just cannot figure out at the
>  moment.
>
>  For example this is what I need in the simplest form
>
>  class myclass():
>   def __init__(self,name):
>   self.name=name
>
>  for count,data in enumerate(some list):
>   instance_count=myclass()
>   instance_count.name=data
>
>  print instances

Okay, to solve your problem, we add a list containing all the instances:

class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for count,data in enumerate(some list):
    instance_count=myclass()
    instance_count.name=data
    instances.append(instance_count)

print instances

=============================================

However, that won't work because myclass has an __init__ with 2
attributes, so you will have to call it using an attribute:

class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for count,data in enumerate(some list):
    instance_count=myclass(data)
    instances.append(instance_count)

print instances

=============================================

This works, but it can be done better:

First we notice that count is not used at all, so why create it?


class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for data in some list:
    instance_count=myclass(data)
    instances.append(instance_count)

print instances

=============================================

Then, the variable instance_count is created once, then used in the
next line. We can do that at once:


class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for data in some list:
    instances.append(myclass(data))

print instances

====================

Finally, "print instances" does not give very nice looking
information, so I would change this to:

class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for data in some list:
    instances.append(myclass(data))

print (instance.name for instance in instances)

-- 
Andr? Engels, andreengels at gmail.com


From python.list at tim.thechases.com  Sun Jul  5 15:21:35 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sun, 05 Jul 2009 14:21:35 -0500
Subject: Creating alot of class instances?
In-Reply-To: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
Message-ID: <4A50FD3F.7080105@tim.thechases.com>

> The solution might be dead simple but I just cannot figure out at the
> moment.
> 
> For example this is what I need in the simplest form
> 
> class myclass():
>  def __init__(self,name):
>  self.name=name
> 
> for count,data in enumerate(some list):
>   instance_count=myclass()
>   instance_count.name=data
> 
> print instances

Sounds like a use for a list:

   instances = []
   for count, data in enumerate(some_list):
     # 1) camel-case is preferred for classnames
     # 2) since your __init__() expects the name
     # pass it in, instead of setting it later
     instance = MyClass(data)
     instances.append(instance)

This can be written in a slightly more condensed-yet-readable 
list-comprehension form as:

   instances = [MyClass(data) for data in some_list]

You then have a list/array of instances you can print:

   print instances

or pick off certain items from it:

   print instances[42]

-tkc





From martin at v.loewis.de  Sun Jul  5 15:23:50 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 05 Jul 2009 21:23:50 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <4A50FDC6.1040604@v.loewis.de>

> This is a good test for Python implementation bottlenecks.  Run
> that tokenizer on HTML, and see where the time goes.

I looked at it with cProfile, and the top function that comes up
for a larger document (52k) is
...validator.HTMLConformanceChecker.__iter__.

This method dispatches various validation routines, and it computes
the method names from the input over and over again, doing lots
of redundant string concatenations. It also capitalizes the element
names, even though the spelling in the original document is probably
not capitalized (but either upper-case or lower case).

In my patch below, I create a dictionary of bound methods, indexed
by (syntax) type and name, following the logic of falling back to
just type-based validation if no type/name routine exists. However,
in order to reduce the number of dictionary lookups, it will also
cache type/name pairs (both in the original spelling, and the
capitalized spelling), so that subsequent occurrences of the same
element will hit the method cache.

With this simple optimization, I get a 20% speedup on my test
case. In my document, there are no attributes - the same changes
should be made to attribute validation routines.

I don't think this has anything to do with the case statement.

Regards,
Martin

-------------- next part --------------
A non-text attachment was scrubbed...
Name: methodlookup.diff
Type: text/x-patch
Size: 2837 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090705/1dcb8735/attachment.bin>

From maymunbeyin at gmail.com  Sun Jul  5 15:54:58 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 12:54:58 -0700 (PDT)
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2648.1246821707.8015.python-list@python.org>
Message-ID: <0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>

Hi

Thank you soo much for speedy and in detailed help. Your replies
really cleared out most of the cloud for me. I have one last issue to
resolve which is something I did not articulate properly, I realize
now. The last issue is actually automatically naming the instances.
The reason I was using the "instance_count" is for enumerating the
actual name of an instance.

For example lets say I have

class MyMaterials:

and my instances might need to look like

material_01
material_02
or
light_01
light_02
or
Mesh_01
Mesh_02 etc

I will need to get the base names from the "some list" and create the
names accordingly from the list array.

Basically I also need to generate the instance names based on the some
list. For example some_list[2] might denote a name for the instance.

I will study the sampled codes in depth now. Maybe you have answered
the naming issue as well, if so please frgove the noise.

thanks






From vasudevram at gmail.com  Sun Jul  5 16:14:31 2009
From: vasudevram at gmail.com (vasudevram)
Date: Sun, 5 Jul 2009 13:14:31 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP: How to define API?
References: <mailman.2520.1246573083.8015.python-list@python.org> 
	<7b5somF21peceU1@mid.uni-berlin.de>
Message-ID: <5328d134-5fb0-4a0f-b24b-86deeeaf97aa@i4g2000prm.googlegroups.com>

On Jul 3, 1:11?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Allen Fowler schrieb:
>
>
>
>
>
>
>
> >> I have an (in-development) python system that needs to shuttle events / requests
> >> around over the network to other parts of itself. ? It will also need to
> >> cooperate with a .net application running on yet a different machine.
>
> >> So, naturally I figured some sort of HTTP event / RPC type of would be a good
> >> idea?
>
> >> Are there any modules I should know about, or guidelines I could read, that
> >> could aid me in the design of the API? ? ?
>
> > To clarify:
>
> > Each message would be <1KB of data total, and consist of some structured object containing strings, numbers, dates, etc.
>
> > For instance there would be an "add user" request that would contain one or more User objects each having a number of properties like:
>
> > - Full Name
> > - Username
> > - Password
> > - Email addresses (a variable length array)
> > - Street Address line1
> > - Street Address line1
> > - Street Address line1
> > - City
> > - State
> > - Zip
> > - Sign Up Date
>
> > .... and so on.
>
> > Since I need to work with other platforms, pickle is out... ?what are the alternatives? ?XML? JSON?
>
> > How should I formally define each of the valid messages and objects?
>
> > Thank you,
>
> Use XMLRPC. Implementations for both languages are available. There is
> no need for formal spec - which is a good thing. You just call the
> server, and it works.
>
> Diez

I second the suggestion of Diez to use XML-RPC. Very simple to learn
and use. Supports structs (as method arguments and method return
values) which can consist of other data types bundled together, also
supports arrays. Just check whether .NET supports XML-RPC.



From ricli85 at gmail.com  Sun Jul  5 16:38:50 2009
From: ricli85 at gmail.com (Rickard Lindberg)
Date: Sun, 5 Jul 2009 22:38:50 +0200
Subject: Creating alot of class instances?
In-Reply-To: <0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2648.1246821707.8015.python-list@python.org>
	<0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>
Message-ID: <890d8ab70907051338p2eaac716qe96f3a1953d4696c@mail.gmail.com>

> Thank you soo much for speedy and in detailed help. Your replies
> really cleared out most of the cloud for me. I have one last issue to
> resolve which is something I did not articulate properly, I realize
> now. The last issue is actually automatically naming the instances.
> The reason I was using the "instance_count" is for enumerating the
> actual name of an instance.
>
> For example lets say I have
>
> class MyMaterials:
>
> and my instances might need to look like
>
> material_01
> material_02
> or
> light_01
> light_02
> or
> Mesh_01
> Mesh_02 etc

If you do not know how many instances you are going to create from the
beginning, there is no way for you to know which of the instances you mentioned
above will get created. So having names for all of the instances will not help
you since you will never know what names are "safe" to use.

On the other hand, if you have all instances in a list, you can refer to them
by index and you know exactly how many of them you have.

If you would like to get instances by some name you gave to them, maybe
something like this will work:

def get_instance(name):
    for instance in instance_list:
        if instance.name == name:
            return instance
    return None

Note that this might very well return None if no instance with that particular
name was found.

-- 
Rickard Lindberg


From no.email at please.post  Sun Jul  5 16:42:41 2009
From: no.email at please.post (kj)
Date: Sun, 5 Jul 2009 20:42:41 +0000 (UTC)
Subject: memoization module?
Message-ID: <h2r381$q5l$1@reader1.panix.com>



Is there a memoization module for Python?  I'm looking for something
like Mark Jason Dominus' handy Memoize module for Perl.

TIA!

kj



From l.mastrodomenico at gmail.com  Sun Jul  5 16:50:30 2009
From: l.mastrodomenico at gmail.com (Lino Mastrodomenico)
Date: Sun, 5 Jul 2009 22:50:30 +0200
Subject: memoization module?
In-Reply-To: <h2r381$q5l$1@reader1.panix.com>
References: <h2r381$q5l$1@reader1.panix.com>
Message-ID: <cc93256f0907051350i5ebbd9eew321e64ea19ebe489@mail.gmail.com>

2009/7/5 kj <no.email at please.post>:
> Is there a memoization module for Python? ?I'm looking for something
> like Mark Jason Dominus' handy Memoize module for Perl.

Check out the "memoized" class example here:

  <http://wiki.python.org/moin/PythonDecoratorLibrary#Memoize>

-- 
Lino Mastrodomenico


From python.list at tim.thechases.com  Sun Jul  5 17:07:45 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sun, 05 Jul 2009 16:07:45 -0500
Subject: Creating alot of class instances?
In-Reply-To: <890d8ab70907051338p2eaac716qe96f3a1953d4696c@mail.gmail.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>	<mailman.2648.1246821707.8015.python-list@python.org>	<0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>
	<890d8ab70907051338p2eaac716qe96f3a1953d4696c@mail.gmail.com>
Message-ID: <4A511621.9050101@tim.thechases.com>

>> For example lets say I have
>>
>> class MyMaterials:
>>
>> and my instances might need to look like
>>
>> material_01
>> material_02
>> or
>> light_01
>> light_02
>> or
>> Mesh_01
>> Mesh_02 etc
> 
> If you do not know how many instances you are going to create from the
> beginning, there is no way for you to know which of the instances you mentioned
> above will get created. So having names for all of the instances will not help
> you since you will never know what names are "safe" to use.
> 
> On the other hand, if you have all instances in a list, you can refer to them
> by index and you know exactly how many of them you have.
> 
> If you would like to get instances by some name you gave to them, maybe
> something like this will work:
> 
> def get_instance(name):
>     for instance in instance_list:
>         if instance.name == name:
>             return instance
>     return None

Another option might be to use a counter in the class that keeps 
track of the number of instances:

   class MyMaterial:
     instances = 0
     def __init__(self, name):
       self.name = name
       self.instance = MyMaterial.instances
       MyMaterial.instances += 1
     def __str__(self):
       return "%s_%02i" % (self.name, self.instance)

   m = MyMaterial("Brick")
   print m
   # "Brick_00"
   print repr([MyMaterial("Stone") for _ in range(5)])
   # "[Stone_01, Stone_02, Stone_03, Stone_04, Stone_05]"

It's not thread-safe, but it may do the trick.

-tkc





From lists at cheimes.de  Sun Jul  5 17:42:41 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sun, 05 Jul 2009 23:42:41 +0200
Subject: Creating alot of class instances?
In-Reply-To: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
Message-ID: <4A511E51.9030408@cheimes.de>

kk wrote:
> I will be querying some data and create class instances based on the
> data I gather. But the problem as I mentioned is that I do not know
> the names and the number of the end class instances. They will be
> based on the content of the data. So how can I create class instances
> within a loop and when the loop is done how can I figure out the list
> of instances via class membership?  I can track the names by
> introducing another list but I want to understand the class side of
> things.

Do you need an exact number or just a rough statistic? In order to
estimate the number of instances you can query the reference count of
the class. Since every instance usually increases the reference count by
one it provides a good overview. Note that lots of other things like
imports increase the reference count, too.

>>> import sys
>>> class Example(object):
...     pass
...
>>> sys.getrefcount(Example)
5
>>> examples = list(Example() for i in range(10))
>>> examples
[<__main__.Example object at 0x7f2e5cd61110>, <__main__.Example object
at 0x7f2e5cd61150>, <__main__.Example object at 0x7f2e5cd61190>,
<__main__.Example object at 0x7f2e5cd611d0>, <__main__.Example object at
0x7f2e5cd61210>, <__main__.Example object at 0x7f2e5cd61250>,
<__main__.Example object at 0x7f2e5cd61390>, <__main__.Example object at
0x7f2e5cd613d0>, <__main__.Example object at 0x7f2e5cd61410>,
<__main__.Example object at 0x7f2e5cd61450>]
>>> sys.getrefcount(Example)
15


From rhodri at wildebst.demon.co.uk  Sun Jul  5 17:47:25 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 05 Jul 2009 22:47:25 +0100
Subject: pep 8 constants
In-Reply-To: <4A4E1B2F.2000700@mrabarnett.plus.com>
References: <mailman.7174.1231915778.3487.python-list@python.org>
	<49a50517$0$3567$426a74cc@news.free.fr> <4A477991.4050109@harvee.org>
	<op.uv89h1xqa8ncjz@gnudebst> <4A484C07.9050800@harvee.org>
	<4A48A495.7040504@tim.thechases.com> <4A48E307.50804@harvee.org>
	<4A49E232.6090101@tim.thechases.com>
	<mailman.2392.1246375713.8015.python-list@python.org>
	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>
	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
	<4A4E135E.5090400@harvee.org> <4A4E1B2F.2000700@mrabarnett.plus.com>
Message-ID: <op.uwl6tbzla8ncjz@gnudebst>

On Fri, 03 Jul 2009 15:52:31 +0100, MRAB <python at mrabarnett.plus.com>  
wrote:

> Eric S. Johansson wrote:
>> Horace Blegg wrote:
>>> I've been kinda following this. I have a cousin who is permanently  
>>> wheel
>>> chair bound and doesn't have perfect control of her hands, but still
>>> manages to use a computer and interact with society. However, the
>>> idea/thought of disabled programmers was new to me/hadn't ever occurred
>>> to me.
>>>
>>> You say that using your hands is painful, but what about your feet?
>>> Wouldn't it be possible to rig up some kind of foot peddle for
>>> shift/caps lock? Kinda like the power peddle used with sowing machines,
>>> so the hands are free to hold fabric.
>>>
>>> I don't mean this in a condescending manor, and I apologize if you take
>>> it as such. I'm genuinely curious if you think something like this  
>>> could
>>> work.
>>>
>>> The way I was envisioning it working last night (and I haven't the
>>> faintest clue how SR works, nor have I ever used SR) was that you would
>>> hit the foot peddle, which would tell the SR program to capitalize the
>>> first letter of the next word (a smart shift, basically, so you don't
>>> end up doing something like ... WONderland -or- "stocks are up 1,0))%
>>> TOday".)
>>>
>>> Possible? Stupid?
>>>
>> it's not stupid.
>>  People have used foot pedals for decades for a variety of controls. I  
>> don't
>> think foot pedals would work for me because when I am dictating, I pace.
>> Standing, sitting, I pace. With a cord headset, I'm forced to stay  
>> within about
>> 4 feet of the computer. But what I'm using a Bluetooth headset, I will  
>> sometimes
>> ramble as far as 10 or 15 feet from the computer. It helps if I make  
>> the font
>> larger so I can glance over and see what kind of errors I've gotten.
>>  I really love a Bluetooth headset with speech recognition. It's so  
>> liberating.
>>  Your question about foot pedals makes me think of alternative. would  
>> it make
>> sense to have a handheld keyboard which would be used for  
>> command-and-control
>> functionality or as an adjunct to speech recognition use? It would have  
>> to be
>> designed in such a way that it doesn't aggravate a hand injury which  
>> may not be
>> possible. Anyway, just thinking out loud.
>>
> You can get giant piano keyboards that you step on, so how about a giant
> computer keyboard? "I wrote 5 miles of code before lunch!" :-)

You can get/make MIDI organ pedal-boards (a friend of mine has two).  From
there it's just one small step...
:-)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From python.list at tim.thechases.com  Sun Jul  5 17:56:07 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sun, 05 Jul 2009 16:56:07 -0500
Subject: pep 8 constants
In-Reply-To: <op.uwl6tbzla8ncjz@gnudebst>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>
	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>
	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>	<4A4E135E.5090400@harvee.org>
	<4A4E1B2F.2000700@mrabarnett.plus.com> <op.uwl6tbzla8ncjz@gnudebst>
Message-ID: <4A512177.8070106@tim.thechases.com>

>> You can get giant piano keyboards that you step on, so how about a giant
>> computer keyboard? "I wrote 5 miles of code before lunch!" :-)
> 
> You can get/make MIDI organ pedal-boards (a friend of mine has two).  From
> there it's just one small step...

Is that a two-step?  a box-step?  Count it off...slow, slow, 
quick, quick.  I think I just coded up Conway's Game of Life...

-tkc





From rhodri at wildebst.demon.co.uk  Sun Jul  5 18:03:13 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 05 Jul 2009 23:03:13 +0100
Subject: PEP368 and pixeliterators
In-Reply-To: <025db110$0$20657$c3e8da3@news.astraweb.com>
References: <mailman.2475.1246523526.8015.python-list@python.org>
	<025db110$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <op.uwl7jngya8ncjz@gnudebst>

On Fri, 03 Jul 2009 09:21:09 +0100, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> wrote:

> On Thu, 02 Jul 2009 10:32:04 +0200, Joachim Str?mbergson wrote:
>
>> for pixel in rgb_image:
>>     # swap red and blue, and set green to 0 pixel.value = pixel.b, 0,
>>     pixel.r
>>
>>
>> The idea I'm having is that fundamentally the image is made up of a 2D
>> array of pixels, not rows of pixels.
>
> A 2D array implies rows (and columns) of pixels.

But not necessarily an internal representation in which those rows or
columns are contiguous.  An efficient internal storage format might
well include margins to make transform edge cases easier, or store
the pixel components in separate arrays, or both.  I'd imagine that
quite frequently, the iterator across all pixels will in fact just
be hiding from the programmer the fact that it's really iterating
by row and then by pixel.  At Python's level of abstraction, that's
just fine, but the assumption that an image is made up of a 2D
array of pixels is not safe.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From torriem at gmail.com  Sun Jul  5 18:27:40 2009
From: torriem at gmail.com (Michael Torrie)
Date: Sun, 05 Jul 2009 16:27:40 -0600
Subject: Wrapping comments
In-Reply-To: <gubl1l$nov$4@lust.ihug.co.nz>
References: <towb-EA7906.14423909052009@news.individual.de>	<K8ydnaPzmfVQEpjXnZ2dnUVZ_gqdnZ2d@pdx.net>	<towb-445608.21342209052009@news.individual.de>	<m2bpq2ngup.fsf@googlemail.com>	<towb-63CE3D.09322210052009@news.individual.de>	<mailman.5400.1242000728.11746.python-list@python.org>	<slrnh0fqu4.qcl.nick@irishsea.home.craig-wood.com>
	<gubl1l$nov$4@lust.ihug.co.nz>
Message-ID: <4A5128DC.5060305@gmail.com>

Lawrence D'Oliveiro wrote:
> I tried using Emacs via SSH from a Mac once. Made me run screaming for the 
> nearest Windows box 
> <http://groups.google.co.nz/group/comp.sys.mac.advocacy/msg/dfad8bff6942e749>.

Interesting rant, but the problem is with the key bindings they chose to
use in Terminal.app program. Fortunately in leopard most of the problems
are now fixed, or can be configured to work in a non-broken fashion.
The rest of us, in the meantime, all switched to iTerm which, although
had some performance issues, behaved like we all expected terminals to
behave.

As far as terminal hell goes, I regularly find that when ssh-ing to
remote boxes that backspace doesn't work.  Or does in bash (because it's
 smart enough to play games) but not in vim.  Somehow sometimes over ssh
the key bindings for backspace get lost of messed up.




From http  Sun Jul  5 18:51:09 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 15:51:09 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
	<0260bf8d$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7x8wj2agma.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> > but I don't accept that "somethingness"
> > vs. "nothingness" is the same distinction as truth vs falsehood.
> 
> It's the distinction used by Python since the dawn of time. Python only 
> grew a bool type a few versions back.

That's true, part of the situation we have now is an artifact of that
history.

> I'm not talking about the constants True and False (nouns), but about 
> true and false values (adjectives).

But, it seems to me, the constants True and False are the only values
to which the adjectives "true" and "false" should be applicable to.

> 
> > The idea that the "if"
> > statement selects between "somethingness" and "nothingness" rather than
> > between True and False is a bogus re-imagining of the traditional
> > function of an "if" statement 
> 
> There's nothing bogus about it.
> 
> > and has been an endless source of bugs in Python code.
> I wonder why these "endless" bugs weren't important enough to be 
> mentioned in the rationale to PEP 285:

Because adding the bool type doesn't really fix those bugs.

> describing `if x` as the "correct form" and calling scrapping such a
> feature as "crippling the language".

Certainly, changing "if" would have broken an immense amount of code
and been a completely unworkable approach.  We are using a fairly 
mature language by now; it has a culture and history that carries
certain baggage, as one should expect.

> > Look how much confusion it causes here in the newsgroup all the time.
> The only confusion is that you're causing me. Would you care to link to 
> some?

This current discussion (about bools) came from such confusion just a
few posts up in this very thread:

    From: upwestdon <upwestdon at gmail.com>
    Date: Fri, 3 Jul 2009 23:03:39 -0700 (PDT)
    How about just:

    if not (self.higher and self.lower):
        return self.higher or self.lower

That test was designed to treat None as a boolean False, without
noticing that numeric 0 is also treated as False and could make the
test do the wrong thing.  This is an extremely common type of error.

> > could see some value to having a generic "is_empty" predicate
> We have that already. It's spelled __bool__ or __nonzero__

That's fine, but under the "explicit is better than implicit"
principle, it's preferable to call that predicate explicitly: 
"if bool(x): ..." rather than "if x:".  Also, after many years of
fixing bugs caused by the mushing together of None and False, it seems
to me that we'd have been better off if bool(None) raised an exception
rather than returning false.  None is supposed to denote a nonexistent
value, not a false or empty value.  The only valid way to check
whether something is None should have been "if x is None".  However,
it is of course way too late to do this differently.

> Iterators are a special case, because in general they can't tell if 
> they're exhausted until they try to yield a value.

Right, it would be nice if they supported a lookahead slot, though
that would complicate a lot of __iter__ methods.  There's been various
kludgy attempts to wrap them in ways that support this, though.


From http  Sun Jul  5 18:53:34 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 15:53:34 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<0a175b39-f084-4814-92e0-80b6cfce6130@c36g2000yqn.googlegroups.com>
Message-ID: <7x4otqagi9.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> BTW, Paul, kind of a tangent: I reimplemented the same algorithm but
> using tuples instead of instances (and empty tuples for "NULL"
> values.)  I was trying to mess around in the space you seemed to
> indicate existed, i.e. a better implementation using other datatypes,
> but I didn't have a clear idea what I was doing and, as I said, I
> started by simply re-implementing with a different datatype.
> 
> Much to my surprise and delight, I discovered the tuple-based BTree
> was /already/ a "persistent data type"!  It was both awesome and a bit
> of an anti-climax. :]

Cool ;-).  It also seems to me a bit irregular to require every tree
to have a node with optional children, rather than allowing trees to be
compleely empty.  I think the irregularity complicated the code somewhat.


From ldo at geek-central.gen.new_zealand  Sun Jul  5 18:54:43 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 10:54:43 +1200
Subject: Wrapping comments
References: <towb-EA7906.14423909052009@news.individual.de>
	<K8ydnaPzmfVQEpjXnZ2dnUVZ_gqdnZ2d@pdx.net>
	<towb-445608.21342209052009@news.individual.de>
	<m2bpq2ngup.fsf@googlemail.com>
	<towb-63CE3D.09322210052009@news.individual.de>
	<mailman.5400.1242000728.11746.python-list@python.org>
	<slrnh0fqu4.qcl.nick@irishsea.home.craig-wood.com>
	<gubl1l$nov$4@lust.ihug.co.nz>
	<mailman.2656.1246832876.8015.python-list@python.org>
Message-ID: <h2ravj$qto$1@lust.ihug.co.nz>

In message <mailman.2656.1246832876.8015.python-list at python.org>, Michael 
Torrie wrote:

> Lawrence D'Oliveiro wrote:
>
>> I tried using Emacs via SSH from a Mac once. Made me run screaming for
>> the nearest Windows box
>> 
<http://groups.google.co.nz/group/comp.sys.mac.advocacy/msg/dfad8bff6942e749>.
> 
> Interesting rant, but the problem is with the key bindings they chose to
> use in Terminal.app program.

Except for control-space, which was defined systemwide to bring up 
Spotlight. So you can't blame the Terminal app for that. The brain damage 
was more widespread than just one program.



From contact at xavierho.com  Sun Jul  5 20:20:39 2009
From: contact at xavierho.com (Xavier Ho)
Date: Mon, 6 Jul 2009 10:20:39 +1000
Subject: Why is my code faster with append() in a loop than with a large list?
Message-ID: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>

(Here's a short version of the long version below if you don't want to
read:)

Why is version B of the code faster than version A? (Only three lines
different)

Version A: http://pastebin.com/f14561243
Version B: http://pastebin.com/f1f657afc

------------------------------------------------

I was doing the problems on Project Euler for practice with Python last
night. Problem 12 was to find the value of the first triangular number that
has over 500 divisors.
=========================================================================================

The sequence of triangle numbers is generated by adding the natural numbers.
So the 7[image: ^(]th[image: )] triangle number would be 1 + 2 + 3 + 4 + 5 +
6 + 7 = 28. The first ten terms would be:

1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...

Let us list the factors of the first seven triangle numbers:

* 1*: 1
* 3*: 1,3
* 6*: 1,2,3,6
*10*: 1,2,5,10
*15*: 1,3,5,15
*21*: 1,3,7,21
*28*: 1,2,4,7,14,28

We can see that 28 is the first triangle number to have over five divisors.

What is the value of the first triangle number to have over five hundred
divisors?
=========================================================================================

My initial code was to loop through from 1 to half the number and see which
were divisors, and as I find them I store them in a list. That would have
taken days.

My second try was factorising the number each time, and count the divisors
using the powers of each factor, plus 1, and multiply together.
The code is here (Version A): http://pastebin.com/f14561243

This worked, but it took overnight to compute. Before I went to bed a friend
of mine caught me online, and apparently left me a working version under 8
seconds with only 3 line difference.
The code is here (Version B): http://pastebin.com/f1f657afc

That was amazing. But I have no idea why his edit makes it so much faster. I
did a test to see whether if append() was faster (which I doubted) than
defining a list with a large size to begin with, and I was right:
http://pastebin.com/f4b46d0db
Which shows that appending is 40x slower, and was expected. But I still
can't puzzle out why his use of appending in Version B was so much faster
than mine.

Any insights would be welcome. I'm going on a family trip, though, so my
replies may delay.

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/853296e4/attachment.html>

From fetchinson at googlemail.com  Sun Jul  5 20:23:49 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Sun, 5 Jul 2009 17:23:49 -0700
Subject: memoization module?
In-Reply-To: <h2r381$q5l$1@reader1.panix.com>
References: <h2r381$q5l$1@reader1.panix.com>
Message-ID: <fbe2e2100907051723i6e40c8e5y468e34112a8070e@mail.gmail.com>

> Is there a memoization module for Python?  I'm looking for something
> like Mark Jason Dominus' handy Memoize module for Perl.

The Python Cookbook has several examples:

http://www.google.com/search?q=python+memoize&sitesearch=code.activestate.com

HTH,
Daniel




-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From ldo at geek-central.gen.new_zealand  Sun Jul  5 20:30:30 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 12:30:30 +1200
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
	<4A4C685A.8020300@Strombergson.com>
	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
	<1f63m.2229$ze1.1410@news-server.bigpond.net.au>
	<mailman.2507.1246557664.8015.python-list@python.org>
Message-ID: <h2rgj7$th1$9@lust.ihug.co.nz>

In message <mailman.2507.1246557664.8015.python-list at python.org>, Charles 
Yeomans wrote:

> On the contrary, MD5 was intended to be a cryptographic hash function,
> not a checksum.

Just like MD4 and MD2 before it. They have long since been considered 
worthless, and now MD5 has joined them.



From Scott.Daniels at Acm.Org  Sun Jul  5 20:30:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sun, 05 Jul 2009 17:30:58 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <4A4FDCAF.8010209@Acm.Org>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org>
Message-ID: <UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>

Scott David Daniels wrote:
> ... Here's a heuristic replacement for my previous frequency code:
> I've tried to mark where you could fudge numbers if the run time
> is at all close.

Boy, I cannot let go.  I did a bit of a test checking for cost to
calculated number of discovered samples, and found after:
     import timeit
     import numpy
     original = numpy.random.random(0, 100, (1000, 1000)).astype(int)
     data = original.flatten()
     data.sort()
     part = data[::100]
     t = timeit.Timer('sum(part[:-1]==part[1:])',
                      'from __main__ import part')
     v = timeit.Timer('len(part[part[:-1]==part[1:]])',
                      'from __main__ import part')

I got:
 >>> t.repeat(3, 10)
[0.58319842326318394, 0.57617574300638807, 0.57831819407238072]
 >>> v.repeat(3, 1000)
[0.93933027801040225, 0.93704535073584339, 0.94096260837613954]

So, len(part[mask]) is almost 50X faster!  I checked:
 >>> sum(part[:-1]==part[1:])
9393
 >>> len(part[part[:-1]==part[1:]])
9393

That's an awful lot of matches, so I with high selectivity:
     data = original.flatten()  # no sorting, so runs missing
     part = data[::100]

 >>> t.repeat(3, 10)
[0.58641335700485797, 0.58458854407490435, 0.58872594142576418]
 >>> v.repeat(3, 1000)
[0.27352554584422251, 0.27375686015921019, 0.27433291102624935]

about 200X faster

 >>> len(part[part[:-1]==part[1:]])
39
 >>> sum(part[:-1]==part[1:])
39

So my new version of this (compressed) code:
>     ...
>     sampled = data[::stride]
>     matches = sampled[:-1] == sampled[1:]
>     candidates = sum(matches) # count identified matches
>     while candidates > N * 10: # 10 -- heuristic
>         stride *= 2 # # heuristic increase
>         sampled = data[::stride]
>         matches = sampled[:-1] == sampled[1:]
>         candidates = sum(matches)
>     while candidates < N * 3: # heuristic slop for long runs
>         stride //= 2 # heuristic decrease
>         sampled = data[::stride]
>         matches = sampled[:-1] == sampled[1:]
>         candidates = sum(matches)
>     former = None
>     past = 0
>     for value in sampled[matches]:
>         ...
is:
       ...
       sampled = data[::stride]
       candidates = sampled[sampled[:-1] == sampled[1:]]
       while len(candidates) > N * 10: # 10 -- heuristic
           stride *= 2 # # heuristic increase
           sampled = data[::stride]
           candidates = sampled[sampled[:-1] == sampled[1:]]
       while len(candidates) < N * 3: # heuristic slop for long runs
           stride //= 2 # heuristic decrease
           sampled = data[::stride]
           candidates = sampled[sampled[:-1] == sampled[1:]]
       former = None
       past = 0
       for value in candidates:
           ...
This change is important, for we try several strides before
settling on a choice, meaning the optimization can be valuable.
This also means we could be pickier at choosing strides (try
more values), since checking is cheaper than before.

Summary: when dealing with numpy, (or any bulk <-> individual values
transitions), try several ways that you think are equivalent and
_measure_.  In the OODB work I did we called this "impedance mismatch,"
and it is likely some boundary transitions are _much_ faster than
others.  The sum case is one of them; I am getting numpy booleans
back, rather than numpy booleans, so conversions aren't going fastpath.

--Scott David Daniels
Scott.Daniels at Acm.Org


From timr at probo.com  Sun Jul  5 20:36:11 2009
From: timr at probo.com (Tim Roberts)
Date: Sun, 05 Jul 2009 17:36:11 -0700
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
Message-ID: <lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>

"jack catcher (nick)" <nomail at thank.you> wrote:
>
>I'm thinking of using Python for capturing and showing live webcam 
>stream simultaneously between two computers via local area network. 
>Operating system is Windows. I'm going to begin with VideoCapture 
>extension, no ideas about other implementation yet. Do you have any 
>suggestions on how short delay I should hope to achieve in showing the 
>video? This would be part of a psychological experiment, so I would need 
>to deliver the video stream with a reasonable delay (say, below 100ms).

You need to do the math on this.  Remember that a full 640x480 RGB stream
at 30 frames per second runs 28 megabytes per second.  That's more than
twice what a 100 megabit network can pump.

You can probably use Python to oversee this, but you might want to consider
using lower-level code to control the actual hardware.  If you are
targeting Windows, for example, you could write a DirectShow graph to pump
into a renderer that transmits out to a network, then another graph to
receive from the network and display it.

You can manage the network latency by adding a delays in the local graph.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From david at pythontoo.com  Sun Jul  5 20:48:39 2009
From: david at pythontoo.com (David)
Date: Sun, 05 Jul 2009 20:48:39 -0400
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <4A5149E7.6030809@pythontoo.com>

Xavier Ho wrote:
> (Here's a short version of the long version below if you don't want to 
> read:)
> 
> Why is version B of the code faster than version A? (Only three lines 
> different)
> 
> Version A: http://pastebin.com/f14561243
> Version B: http://pastebin.com/f1f657afc
I don't know but here is the diff for someone that may;

1c1,2
< # This one only took 8 seconds on my machine. Wow?
---
 >
 > # This one took hours to compute, overnight.
28c29
<     powers = [0, 0]
---
 >     powers = [0] * (num + 1)
32c33
<             powers[factor-1] += 1
---
 >             powers[factor] += 1
35d35
<             powers.append(0)
55c55
<     n += 1
\ No newline at end of file
---
 >     n += 1


-- 
Powered by Gentoo GNU/Linux
http://linuxcrazy.com


From python at mrabarnett.plus.com  Sun Jul  5 20:54:39 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 01:54:39 +0100
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <4A514B4F.6010408@mrabarnett.plus.com>

Xavier Ho wrote:
> (Here's a short version of the long version below if you don't want to 
> read:)
> 
> Why is version B of the code faster than version A? (Only three lines 
> different)
> 
> Version A: http://pastebin.com/f14561243
> Version B: http://pastebin.com/f1f657afc
> 
> ------------------------------------------------
> 
> I was doing the problems on Project Euler for practice with Python last 
> night. Problem 12 was to find the value of the first triangular number 
> that has over 500 divisors.
> =========================================================================================
> 
> The sequence of triangle numbers is generated by adding the natural 
> numbers. So the 7^(^th ) triangle number would be 1 + 2 + 3 + 4 + 5 + 6 
> + 7 = 28. The first ten terms would be:
> 
> 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
> 
> Let us list the factors of the first seven triangle numbers:
> 
>     * 1*: 1
>     * 3*: 1,3
>     * 6*: 1,2,3,6
>     *10*: 1,2,5,10
>     *15*: 1,3,5,15
>     *21*: 1,3,7,21
>     *28*: 1,2,4,7,14,28
> 
> We can see that 28 is the first triangle number to have over five divisors.
> 
> What is the value of the first triangle number to have over five hundred 
> divisors?
> 
> =========================================================================================
> 
> My initial code was to loop through from 1 to half the number and see 
> which were divisors, and as I find them I store them in a list. That 
> would have taken days.
> 
> My second try was factorising the number each time, and count the 
> divisors using the powers of each factor, plus 1, and multiply together.
> The code is here (Version A): http://pastebin.com/f14561243
> 
> This worked, but it took overnight to compute. Before I went to bed a 
> friend of mine caught me online, and apparently left me a working 
> version under 8 seconds with only 3 line difference.
> The code is here (Version B): http://pastebin.com/f1f657afc
> 
> That was amazing. But I have no idea why his edit makes it so much 
> faster. I did a test to see whether if append() was faster (which I 
> doubted) than defining a list with a large size to begin with, and I was 
> right:
> http://pastebin.com/f4b46d0db
> Which shows that appending is 40x slower, and was expected. But I still 
> can't puzzle out why his use of appending in Version B was so much 
> faster than mine.
> 
> Any insights would be welcome. I'm going on a family trip, though, so my 
> replies may delay.
> 
In your version you're creating a list of (num + 1) elements, but in the
other version the list is only as long as the largest factor.

For example, for num=28, your version creates a list 29 elements long,
but the other version creates one only 7 elements long. Also, 'the time
needed to append an item to the list is "amortized constant"' (quoted
from http://effbot.org/zone/python-list.htm).

This means that your little speed test isn't representation of what's
actually happening.


From notvalid2 at sbcglobal.net  Sun Jul  5 21:48:46 2009
From: notvalid2 at sbcglobal.net (W. eWatson)
Date: Sun, 05 Jul 2009 18:48:46 -0700
Subject: Adding the Copy Property to a Simple Histogram
Message-ID: <WJc4m.2086$8r.1195@nlpi064.nbdc.sbc.com>

The code below produces a text window 60hx20w with a scroll bar. The 
contents are something of a histogram of values from 0 to 255. If one tries 
to copy the contents, Windows doesn't allow it. What needs to be done to 
allow a copy and paste?

     def ShowHistogram(self):
         if not self.current_image:
             return

         if self.histogram:
             self.histogram.destroy()

         t = Toplevel( self.master )
         t.title("Histogram")
         t.bind( '<Destroy>', self.DestroyHistogram )
         text = Text( t, height=60, width=20 )
         scroll = Scrollbar(t, command=text.yview)
         text.configure(yscrollcommand=scroll.set)
         text.pack(side=LEFT, fill='both', expand=1)
         scroll.pack(side=RIGHT, fill=Y)
         self.histogram = t

         hist = self.current_image.histogram()
         for i in range(len(hist)):
             msg = "%5d %6d\n" % (i,hist[i])
             text.insert( END, msg )
-- 
                                W. eWatson

              (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
               Obz Site:  39? 15' 7" N, 121? 2' 32" W, 2700 feet

                     Web Page: <www.speckledwithstars.net/>



From tanner989 at hotmail.com  Sun Jul  5 22:06:30 2009
From: tanner989 at hotmail.com (tanner barnes)
Date: Sun, 5 Jul 2009 21:06:30 -0500
Subject: Help with Sockets.
Message-ID: <BAY122-W4920057777399CD2F5C824F52B0@phx.gbl>


I am writing a program and in one section there is going to be a lobby with (for testing purposes) about 4 people in it. in the lobby there are two txtctrl's the first for entering your message and the second for displaying the message you and the other people in the lobby type. i am trying to figure out how to get all the text entrys from the users and display them in the second one. For clarification and example of what i want would be like yahoo or windows live messanger but for more than 2 people. 

Python version: 2.6
GUI toolkit: WxPython


_________________________________________________________________
Hotmail? has ever-growing storage! Don?t worry about storage limits. 
http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090705/9296433d/attachment.html>

From maymunbeyin at gmail.com  Sun Jul  5 22:27:25 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 19:27:25 -0700 (PDT)
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
Message-ID: <22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>

Hi

Thank you so much for wonderful tips and suggestions.

I also found a solution to dynamic naming of the instances(I think).
It does not sound like a very secure method but since my application
will be just processing data one way I think it might be alright. I
will compare to the list and dictionary methods.

globals()["Some_Instance_Name"]



From ldo at geek-central.gen.new_zealand  Sun Jul  5 22:32:46 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 14:32:46 +1200
Subject: A Bug By Any Other Name ...
Message-ID: <h2rnoe$26s$5@lust.ihug.co.nz>

I wonder how many people have been tripped up by the fact that

    ++n

and

    --n

fail silently for numeric-valued n.



From clp2 at rebertia.com  Sun Jul  5 22:45:39 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 5 Jul 2009 19:45:39 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2rnoe$26s$5@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <50697b2c0907051945x67f97094s370449fa6d05b449@mail.gmail.com>

On Sun, Jul 5, 2009 at 7:32 PM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> I wonder how many people have been tripped up by the fact that
>
> ? ?++n
>
> and
>
> ? ?--n
>
> fail silently for numeric-valued n.

Given that C-style for-loops are relatively infrequent in Python and
are usually written using range() when they are needed, it's probably
not that prevalent a problem.
I suppose the lexer could be changed to make ++ and -- illegal...

Cheers,
Chris
-- 
http://blog.rebertia.com


From sajmikins at gmail.com  Sun Jul  5 23:11:51 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sun, 5 Jul 2009 20:11:51 -0700 (PDT)
Subject: Adding the Copy Property to a Simple Histogram
References: <WJc4m.2086$8r.1195@nlpi064.nbdc.sbc.com>
Message-ID: <a545e526-a6fe-4411-9603-a85722f526fa@d32g2000yqh.googlegroups.com>

On Jul 5, 9:48?pm, "W. eWatson" <notval... at sbcglobal.net> wrote:
> The code below produces a text window 60hx20w with a scroll bar. The
> contents are something of a histogram of values from 0 to 255. If one tries
> to copy the contents, Windows doesn't allow it. What needs to be done to
> allow a copy and paste?
>
> ? ? ?def ShowHistogram(self):
> ? ? ? ? ?if not self.current_image:
> ? ? ? ? ? ? ?return
>
> ? ? ? ? ?if self.histogram:
> ? ? ? ? ? ? ?self.histogram.destroy()
>
> ? ? ? ? ?t = Toplevel( self.master )
> ? ? ? ? ?t.title("Histogram")
> ? ? ? ? ?t.bind( '<Destroy>', self.DestroyHistogram )
> ? ? ? ? ?text = Text( t, height=60, width=20 )
> ? ? ? ? ?scroll = Scrollbar(t, command=text.yview)
> ? ? ? ? ?text.configure(yscrollcommand=scroll.set)
> ? ? ? ? ?text.pack(side=LEFT, fill='both', expand=1)
> ? ? ? ? ?scroll.pack(side=RIGHT, fill=Y)
> ? ? ? ? ?self.histogram = t
>
> ? ? ? ? ?hist = self.current_image.histogram()
> ? ? ? ? ?for i in range(len(hist)):
> ? ? ? ? ? ? ?msg = "%5d %6d\n" % (i,hist[i])
> ? ? ? ? ? ? ?text.insert( END, msg )
> --
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? W. eWatson
>
> ? ? ? ? ? ? ? (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
> ? ? ? ? ? ? ? ?Obz Site: ?39? 15' 7" N, 121? 2' 32" W, 2700 feet
>
> ? ? ? ? ? ? ? ? ? ? ?Web Page: <www.speckledwithstars.net/>

Do you mean that the Text widget doesn't let you copy-and-paste copy
its contents using selection and <Control-c>?  That shouldn't have
anything to do with the contents of the Text widget.


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 23:28:43 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 03:28:43 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <006d4a50$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:

> I wonder how many people have been tripped up by the fact that
> 
>     ++n
> 
> and
> 
>     --n
> 
> fail silently for numeric-valued n.

What do you mean, "fail silently"? They do exactly what you should expect:


>>> ++5  # positive of a positive number is positive
5
>>> --5  # negative of a negative number is positive
5
>>> -+5  # negative of a positive number is negative
-5

So does the bitwise-not unary operator:

>>> ~~5
5


I'm not sure what "bug" you're seeing. Perhaps it's your expectations 
that are buggy, not Python.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 23:28:55 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 03:28:55 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org> <UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>
Message-ID: <006d4a5c$0$9711$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 17:30:58 -0700, Scott David Daniels wrote:

> Summary: when dealing with numpy, (or any bulk <-> individual values
> transitions), try several ways that you think are equivalent and
> _measure_.

This advice is *much* more general than numpy -- it applies to any 
optimization exercise. People's intuitions about what's fast and what's 
slow are often very wrong.


-- 
Steven


From notvalid2 at sbcglobal.net  Sun Jul  5 23:33:48 2009
From: notvalid2 at sbcglobal.net (W. eWatson)
Date: Sun, 05 Jul 2009 20:33:48 -0700
Subject: Adding the Copy Property to a Simple Histogram
In-Reply-To: <a545e526-a6fe-4411-9603-a85722f526fa@d32g2000yqh.googlegroups.com>
References: <WJc4m.2086$8r.1195@nlpi064.nbdc.sbc.com>
	<a545e526-a6fe-4411-9603-a85722f526fa@d32g2000yqh.googlegroups.com>
Message-ID: <rge4m.2366$Wj7.1684@nlpi065.nbdc.sbc.com>

Simon Forman wrote:
> On Jul 5, 9:48 pm, "W. eWatson" <notval... at sbcglobal.net> wrote:
>> The code below produces a text window 60hx20w with a scroll bar. The
>> contents are something of a histogram of values from 0 to 255. If one tries
>> to copy the contents, Windows doesn't allow it. What needs to be done to
>> allow a copy and paste?
>>
>>      def ShowHistogram(self):
>>          if not self.current_image:
>>              return
>>
>>          if self.histogram:
>>              self.histogram.destroy()
>>
>>          t = Toplevel( self.master )
>>          t.title("Histogram")
>>          t.bind( '<Destroy>', self.DestroyHistogram )
>>          text = Text( t, height=60, width=20 )
>>          scroll = Scrollbar(t, command=text.yview)
>>          text.configure(yscrollcommand=scroll.set)
>>          text.pack(side=LEFT, fill='both', expand=1)
>>          scroll.pack(side=RIGHT, fill=Y)
>>          self.histogram = t
>>
>>          hist = self.current_image.histogram()
>>          for i in range(len(hist)):
>>              msg = "%5d %6d\n" % (i,hist[i])
>>              text.insert( END, msg )
>> --
>>                                 W. eWatson
>>
>>               (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
>>                Obz Site:  39? 15' 7" N, 121? 2' 32" W, 2700 feet
>>
>>                      Web Page: <www.speckledwithstars.net/>
> 
> Do you mean that the Text widget doesn't let you copy-and-paste copy
> its contents using selection and <Control-c>?  That shouldn't have
> anything to do with the contents of the Text widget.
Whoops, I missed it. I'm not quite sure what I did to make it seem like it 
doesn't copy, but it does. I fooled myself. All is well.

-- 
                                W. eWatson

              (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
               Obz Site:  39? 15' 7" N, 121? 2' 32" W, 2700 feet

                     Web Page: <www.speckledwithstars.net/>



From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 23:46:41 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 03:46:41 GMT
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
Message-ID: <006d4e86$0$9711$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 19:27:25 -0700, kk wrote:

> Hi
> 
> Thank you so much for wonderful tips and suggestions.
> 
> I also found a solution to dynamic naming of the instances(I think). It
> does not sound like a very secure method but since my application will
> be just processing data one way I think it might be alright. I will
> compare to the list and dictionary methods.
> 
> globals()["Some_Instance_Name"]


You're fighting the computer instead of working with it. That's the Wrong 
Way to solve the problem -- you're doing more work than needed, for 
little or no benefit.

My bet is, you have code that looks something like this:


for i in range(N):  # N comes from somewhere else
    # Create a new variable
    globals()["Some_Instance_Name%s" % i] = instance()

# Do something with the variables
for i in range(N):
    # Look up the variable
    x = globals()["Some_Instance_Name%s" % i]
    process(x)


Am I close?

That's the Wrong Way to do it -- you're using a screwdriver to hammer a 
nail. The right way to work with an unknown number of data elements is to 
put them in a list, and process each element in the list, not to try 
giving them all unique names. The only reason for using named variables 
is so you can use the name in source code:

my_value = Some_Instance87 + Some_Instance126

But you can't do that, because you don't know how many instances there 
are, you don't know whether to write Some_Instance87 or Some_Instance125 
or Some_Instance19.


So instead, do something like this:


instances = []
for i in range(N):
    # Create a new instance and store it for later
    instances.append( instance() )

# Later on:
for x in instances():
    process(x)




-- 
Steven


From dns4 at cornell.edu  Sun Jul  5 23:53:56 2009
From: dns4 at cornell.edu (David Smith)
Date: Sun, 05 Jul 2009 23:53:56 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2oggj$n9p$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
	<7x4otsux7f.fsf@ruckus.brouhaha.com>
	<h2oggj$n9p$1@reader1.panix.com>
Message-ID: <h2rsgi$7s2$1@ruby.cit.cornell.edu>

kj wrote:
> In <7x4otsux7f.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:
> 
>> kj <no.email at please.post> writes:
>>>     sense = cmp(func(hi), func(lo))
>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
> 
>> bisection search usually just requires the function to be continuous
>> and to have its value cross the target somewhere between the endpoints,
>> not be monotonic.
> 
> Try the algorithm I posted with lo = -pi/4, hi = 2*pi, func = cos,
> target = -1, and see what you get...
> 
>>> I regard the very special case of func(hi)==func(lo)==target as
>>> pathological (analogous to the fact that a stopped watch is "exactly
>>> right" twice a day), and not one I care to support.
> 
>> I do think you should support that case, under the "do 'nothing'
>> gracefully" principle.
> 
> You keep missing the point that this is an *internal* *helper*
> *convenience* function, meant to abstract away common logic from
> a handful of places and thus eliminate some code repetition within
> a module.  It is *not* a library function intended to be called
> from elsewhere.  So talk of "supporting" anything is besides the
> point.  Any internal use of this function that applies it to a
> non-strictly-monotonic function is, by assumption, an error.
> 
> kj

First, let me say *I got the point*.  I use asserts, but only in unit
testing where I want to test the result of some action for correctness.
 In the course of programming product code, I personally don't think
they should ever be used exactly for the reasons everyone else is
pointing out.  They can be disabled with the -O option and that changes
the program's behavior in ways that could break in production.

If you insist on teaching the assert statement, teach it in the context
of writing unit testing code.  Its an extremely valuable skill.

--David


From casevh at gmail.com  Mon Jul  6 01:04:36 2009
From: casevh at gmail.com (casevh)
Date: Sun, 5 Jul 2009 22:04:36 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
Message-ID: <mailman.2695.1246892380.8015.python-announce-list@python.org>

An alpha release of GMPY that supports Python 2 and 3 is available.
GMPY is a wrapper for the GMP multiple-precision arithmetic
library. The MPIR multiple-precision arithmetic library is also
supported. GMPY is available for download from
http://code.google.com/p/gmpy/

Support for Python 3 required many changes to the logic used to
convert between different numerical types. The result type of some
combinations has changed. For example, 'mpz' + 'float' now returns
an 'mpf' instead of a 'float'. See the file "changes.txt" for more
information.

In addition to support for Python 3, there are several other
changes and bug fixes:

- Bug fixes in mpz.binary() and mpq.binary().

- Unicode strings are accepted as input on Python 2.
  (Known bug: works for mpz, fails for mpq and mpf)

- The overhead for calling GMPY routines has been reduced.
  If one operand in a small integer, it is not converted to mpz.

- 'mpf' and 'mpq' now support % and divmod.

Comments on provided binaries

The 32-bit Windows installers were compiled using MPIR 1.2.1 and
will automatically recognize the CPU type and use code optimized for
that CPU.

Please test with your applications and report any issues found!

casevh


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 01:19:51 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 02:19:51 -0300
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> escribi?:
> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>
>> I wonder how many people have been tripped up by the fact that
>>
>>     ++n
>>
>> and
>>
>>     --n
>>
>> fail silently for numeric-valued n.
>
> What do you mean, "fail silently"? They do exactly what you should  
> expect:
>>>> ++5  # positive of a positive number is positive
>
> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
> that are buggy, not Python.

Well, those expectations are taken seriously when new features are  
introduced into the language - and sometimes the feature is dismissed just  
because it would be confusing for some.
If a += 1 works, expecting ++a to have the same meaning is very reasonable  
(for those coming from languages with a ++ operator, like C or Java) -  
more when ++a is a perfectly valid expression.
If this issue isn't listed under the various "Python gotchas" articles, it  
should...

-- 
Gabriel Genellina



From banibrata.dutta at gmail.com  Mon Jul  6 01:37:19 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Mon, 6 Jul 2009 11:07:19 +0530
Subject: mail
In-Reply-To: <22154.210.212.36.65.1246724472.squirrel@www.iisermohali.ac.in>
References: <22154.210.212.36.65.1246724472.squirrel@www.iisermohali.ac.in>
Message-ID: <3de8e1f70907052237m442e563bj4e040eec12d63f0d@mail.gmail.com>

On Sat, Jul 4, 2009 at 9:51 PM, <amrita at iisermohali.ac.in> wrote:

> Hi,
>
> I want to know that whether using python programming is it possible to
> extract chemical shift information about some amino acids of some protein
> from BMRB(BioMagResBank) or Ref-DB(referenced databank) or not.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
>

Without any real knowledge of the problem domain, but with keyword level
google search, here's one one finds --
http://www.ccpn.ac.uk/api-documentation/ccpnmr/ccpnmr2.0/python/doc/api.html
<http://www.ccpn.ac.uk/api-documentation/ccpnmr/ccpnmr2.0/python/doc/api.html>
http://biopython.org/wiki/Main_Page
<http://biopython.org/wiki/Main_Page>http://chempython.org/
<http://chempython.org/>http://www.sschwarzer.net/

Also as Grant says, if you can create a software program in any language,
you can potentially do it with Python as well. As Python is a "batteries
included" language, chances are, the included-batteries would make your life
easier. Of course mileage may vary. If you find existing modules that do
much of what you want, you have a very good starting point.
-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/8d72613c/attachment.html>

From maymunbeyin at gmail.com  Mon Jul  6 01:50:36 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 22:50:36 -0700 (PDT)
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <b5040c01-ce88-4edb-8b9a-7bb3b58d4e2a@g19g2000yql.googlegroups.com>

Steven,

Before your post I was contemplating about the merits of using the
globals(). After reading your post I am totally convinced that your
suggestion that was also suggested by previous posters is the way to
go. At first I thought it would be limiting to not to have the
instance names properly setup, but now I understand it better.

thank you all again.


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 01:58:59 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 02:58:59 -0300
Subject: Does cProfile include IO wait time?
References: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>
Message-ID: <op.uwmtkllgx6zn5v@lepton.softlabbsas.com.ar>

En Sat, 04 Jul 2009 21:03:38 -0300, Matthew Wilson <matt at tplus1.com>  
escribi?:

> I expected to see a bunch of my IO file-reading code in there, but I  
> don't.  So
> this makes me think that the profiler uses CPU time, not
> clock-on-the-wall time.
> I'm not an expert on python profiling, and the docs seem sparse.  Can I
> rule out IO as the bottleneck here?  How do I see the IO consequences?

I don't know either - but it's easy to check.
Write a program that just reads a lot from /dev/zero, and look at its  
profile. You should be able to tell whether I/O time is included or not.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 02:10:25 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 03:10:25 -0300
Subject: Help with Sockets.
References: <BAY122-W4920057777399CD2F5C824F52B0@phx.gbl>
Message-ID: <op.uwmt3nbmx6zn5v@lepton.softlabbsas.com.ar>

En Sun, 05 Jul 2009 23:06:30 -0300, tanner barnes <tanner989 at hotmail.com>  
escribi?:

> I am writing a program and in one section there is going to be a lobby  
> with (for testing purposes) about 4 people in it. in the lobby there are  
> two txtctrl's the first for entering your message and the second for  
> displaying the message you and the other people in the lobby type. i am  
> trying to figure out how to get all the text entrys from the users and  
> display them in the second one. For clarification and example of what i  
> want would be like yahoo or windows live messanger but for more than 2  
> people.

Like a chat room, IRC?
It's easy to do using a client-server architecture.
Make all the clients connect to a central server. Any time someone writes  
some text, the client sends it to the server (but does not display it).  
The server just receives text from any client, and sends the received  
messages to all connected clients (including the one that sent it  
originally).
Any book on socket programming will help; there are a few specific for  
Python.
You may start with the "echo" example in the Python documentation. Make  
the networking part work first, then add the wx GUI if you want.

-- 
Gabriel Genellina



From nomail at thank.you  Mon Jul  6 02:10:38 2009
From: nomail at thank.you (jack catcher (nick))
Date: Mon, 06 Jul 2009 09:10:38 +0300
Subject: Python and webcam capture delay?
In-Reply-To: <lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
Message-ID: <czg4m.20786$vi5.9666@uutiset.elisa.fi>

Tim Roberts kirjoitti:
> "jack catcher (nick)" <nomail at thank.you> wrote:
>> I'm thinking of using Python for capturing and showing live webcam 
>> stream simultaneously between two computers via local area network. 
>> Operating system is Windows. I'm going to begin with VideoCapture 
>> extension, no ideas about other implementation yet. Do you have any 
>> suggestions on how short delay I should hope to achieve in showing the 
>> video? This would be part of a psychological experiment, so I would need 
>> to deliver the video stream with a reasonable delay (say, below 100ms).
> 
> You need to do the math on this.  Remember that a full 640x480 RGB stream
> at 30 frames per second runs 28 megabytes per second.  That's more than
> twice what a 100 megabit network can pump.
> 
> You can probably use Python to oversee this, but you might want to consider
> using lower-level code to control the actual hardware.  If you are
> targeting Windows, for example, you could write a DirectShow graph to pump
> into a renderer that transmits out to a network, then another graph to
> receive from the network and display it.
> 
> You can manage the network latency by adding a delays in the local graph.

Thanks Tim, you're correct about the math. What is your main point about 
DirectShow: that it is generally faster and more reliable than doing the 
job high-level, or that one could use coding/decoding in DirectShow to 
speed up the transmission? I think the latter would be a great idea if 
the latency were tolerable. On the other hand, I'd like to keep things 
simple and do all the programming in Python. I've got no experience with 
DirectShow, but I guess the filters need to be programmed in C++ and 
called from Python?

Another option might be to use resolution 320x240 at 15fps.


From gherron at islandtraining.com  Mon Jul  6 02:33:36 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Sun, 05 Jul 2009 23:33:36 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A519AC0.1050905@islandtraining.com>

Gabriel Genellina wrote:
> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano 
> <steve at remove-this-cybersource.com.au> escribi?:
>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>
>>> I wonder how many people have been tripped up by the fact that
>>>
>>>     ++n
>>>
>>> and
>>>
>>>     --n
>>>
>>> fail silently for numeric-valued n.
>>
>> What do you mean, "fail silently"? They do exactly what you should 
>> expect:
>>>>> ++5  # positive of a positive number is positive
>>
>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>> that are buggy, not Python.
>
> Well, those expectations are taken seriously when new features are 
> introduced into the language - and sometimes the feature is dismissed 
> just because it would be confusing for some.
> If a += 1 works, expecting ++a to have the same meaning is very 
> reasonable (for those coming from languages with a ++ operator, like C 
> or Java) - more when ++a is a perfectly valid expression.
> If this issue isn't listed under the various "Python gotchas" 
> articles, it should...

Well sure, it's not unreasonable to expect ++n and --n to behave as in 
other languages, and since they don't, perhaps they should be listed as 
a "Python gotcha". 

But even so, it's quite arrogant of the OP to flaunt his ignorance of 
the language by claiming this is a bug and a failure.  It shouldn't have 
been all that hard for him to figure out what was really happening.

Gary Herron



From __peter__ at web.de  Mon Jul  6 02:33:53 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 06 Jul 2009 08:33:53 +0200
Subject: finding most common elements between thousands of multiple arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org>
	<UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>
Message-ID: <h2s5rm$m95$01$1@news.t-online.com>

Scott David Daniels wrote:

> Scott David Daniels wrote:

>      t = timeit.Timer('sum(part[:-1]==part[1:])',
>                       'from __main__ import part')

What happens if you calculate the sum in numpy? Try

t = timeit.Timer('(part[:-1]==part[1:]).sum()',
                 'from __main__ import part')


Peter



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 02:46:33 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 03:46:33 -0300
Subject: Method to separate unit-test methods and data?
References: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
	<be8f57070907051148x52ee305ch905c79bb0d59d983@mail.gmail.com>
Message-ID: <op.uwmvrvesx6zn5v@lepton.softlabbsas.com.ar>

En Sun, 05 Jul 2009 15:48:06 -0300, Nick Daly <nick.m.daly at gmail.com>  
escribi?:

> [test_Midpoint_mid]
> none_values = ((-1, None),
> ? ? ? ? ? ? ? (None, -12.8))
>
> What I haven't yet figured out how to do though, is properly override
> the default class member values with values from the config file. ?The
> config file's data is loaded as a string instead of as a list, as I'd
> want. ?This causes all the tests to fail, as while none_values needs
> to be interpreted as a list, it is instead understood as:
>
> " ((-1, None),\n ? ? ? ? ? ? ? (None, -12.8))"
>
> Does anyone have any solutions for these problems? ?

You may use a .py file to configure it, instead of your .cfg

> First, is there a
> known and simple way to separate unit-test data and methods into
> separate files? ?

Just write them in separate files? I didn't quite understand the  
question...

> Secondly, if not, is there a simple way to convert
> strings into other base types, like lists, dictionaries, and so forth?

eval(), but I'd just use a .py file
People usually warns against using eval on arbitrary strings, or on  
user-supplied data, but in this case it is not worse than  
importing/executing the module.

> Or, am I going to have to write my own list-parsing methods? ?Would
> pickling help? ?I haven't yet had a chance to look into if or how that
> would work... ?If there's anything else I can clarify about this
> request, feel free to let me know.

Another alternative would be a .csv file; I use them when the test data  
comes from other parties, like a manufacturer's data sheet.

I've never used a pickle to store test data - how do you generate the  
pickle contents in the first place? Usually I'd just use *that* code  
directly, but I think pickling the resulting objects would be OK is the  
process to regenerate them takes a lot of time.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 02:53:57 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 03:53:57 -0300
Subject: multiprocessing and freezing on Windows
References: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>
	<a205db1d-a801-4774-bfa1-124a723ea71b@p36g2000prn.googlegroups.com>
Message-ID: <op.uwmv37hsx6zn5v@lepton.softlabbsas.com.ar>

En Sat, 04 Jul 2009 22:15:43 -0300, SK <sgm at objexx.com> escribi?:

> To add a bit more information, I found that I needed to patch
> get_command_line in multiprocessing/forking.py [...]
>
> Is packaging with multiprocessing supposed to be this hard? If so,
> some documentation is needed.

Shouldn't be so hard, I presume. You may want to post your comments and  
upload the patch to http://bugs.python.org

-- 
Gabriel Genellina



From martin at librador.com  Mon Jul  6 03:44:33 2009
From: martin at librador.com (Martin Vilcans)
Date: Mon, 6 Jul 2009 09:44:33 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>

On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse. ?I'd love your opinion about
> it.

In general, code clarity is more important than reusability.
Unfortunately, many novice programmers have the opposite impression. I
have seen too much convoluted code written by beginners who try to
make the code generic. Writing simple, clear, to-the-point code is
hard enough as it is, even when not aiming at making it reusable.

If in the future you see an opportunity to reuse the code, then and
only then is the time to make it generic.

YAGNI is a wonderful principle.

-- 
martin at librador.com
http://www.librador.com


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 03:49:28 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 04:49:28 -0300
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
Message-ID: <op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 03:33:36 -0300, Gary Herron  
<gherron at islandtraining.com> escribi?:
> Gabriel Genellina wrote:
>> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano  
>> <steve at remove-this-cybersource.com.au> escribi?:
>>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>>
>>>> I wonder how many people have been tripped up by the fact that
>>>>
>>>>     ++n
>>>>
>>>> and
>>>>
>>>>     --n
>>>>
>>>> fail silently for numeric-valued n.
>>>
>>> What do you mean, "fail silently"? They do exactly what you should  
>>> expect:
>>>>>> ++5  # positive of a positive number is positive
>>>
>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>> that are buggy, not Python.
>>
>> Well, those expectations are taken seriously when new features are  
>> introduced into the language - and sometimes the feature is dismissed  
>> just because it would be confusing for some.
>> If a += 1 works, expecting ++a to have the same meaning is very  
>> reasonable (for those coming from languages with a ++ operator, like C  
>> or Java) - more when ++a is a perfectly valid expression.
>> If this issue isn't listed under the various "Python gotchas" articles,  
>> it should...
>
> Well sure, it's not unreasonable to expect ++n and --n to behave as in  
> other languages, and since they don't, perhaps they should be listed as  
> a "Python gotcha". But even so, it's quite arrogant of the OP to flaunt  
> his ignorance of the language by claiming this is a bug and a failure.   
> It shouldn't have been all that hard for him to figure out what was  
> really happening.

That depends on what you call a "bug". In his classical book "The art of  
software testing", Myers says that a program has a bug when it doesn't  
perform as the user expects reasonably it to do (not an exact quote, I  
don't have the book at hand). That's a lot broader than developers like to  
accept.

In this case, a note in the documentation warning about the potential  
confusion would be fine.

-- 
Gabriel Genellina



From andreengels at gmail.com  Mon Jul  6 03:51:04 2009
From: andreengels at gmail.com (Andre Engels)
Date: Mon, 6 Jul 2009 09:51:04 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
Message-ID: <6faf39c90907060051n65089c88od45c75c80f3a7ccf@mail.gmail.com>

On Mon, Jul 6, 2009 at 9:44 AM, Martin Vilcans<martin at librador.com> wrote:
> On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
>> I'm will be teaching a programming class to novices, and I've run
>> into a clear conflict between two of the principles I'd like to
>> teach: code clarity vs. code reuse. ?I'd love your opinion about
>> it.
>
> In general, code clarity is more important than reusability.
> Unfortunately, many novice programmers have the opposite impression. I
> have seen too much convoluted code written by beginners who try to
> make the code generic. Writing simple, clear, to-the-point code is
> hard enough as it is, even when not aiming at making it reusable.
>
> If in the future you see an opportunity to reuse the code, then and
> only then is the time to make it generic.

Not just that, when you actually get to that point, making simple and
clear code generic is often easier than making
complicated-and-supposedly-generic code that little bit more generic
that you need.


-- 
Andr? Engels, andreengels at gmail.com


From mail at timgolden.me.uk  Mon Jul  6 03:56:20 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 06 Jul 2009 08:56:20 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A51AE24.9080608@timgolden.me.uk>

Gabriel Genellina wrote:

[... re confusion over ++n etc ...]

> In this case, a note in the documentation warning about the potential 
> confusion would be fine.

The difficulty here is knowing where to put such a warning.
You obviously can't put it against the "++" operator as such
because... there isn't one. You could put it against the unary
plus operator, but who's going to look there? :)

I've wondered for a while whether it wouldn't be a good move
to include the official (or any other) Python FAQ into the
standard docs set. If we did, that would be the obvious place
for this piece of documentation, seems to me.

TJG


From stef.mientki at gmail.com  Mon Jul  6 04:05:32 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Mon, 06 Jul 2009 10:05:32 +0200
Subject: Python and webcam capture delay?
In-Reply-To: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
Message-ID: <4A51B04C.2080207@gmail.com>

jack catcher (nick) wrote:
> Hi,
>
> I'm thinking of using Python for capturing and showing live webcam 
> stream simultaneously between two computers via local area network. 
> Operating system is Windows. I'm going to begin with VideoCapture 
> extension, no ideas about other implementation yet. Do you have any 
> suggestions on how short delay I should hope to achieve in showing the 
> video? This would be part of a psychological experiment, so I would 
> need to deliver the video stream with a reasonable delay (say, below 
> 100ms).
I would first check if video capture extension works anyway.
I couldn't get it working, ...
... it seems to start ok
... but moving the captured window,
... or sometimes even just moving the mouse hangs the program :-(

So I'm still looking for a good / open source workiing video capture in 
Python.
I can make a good working capture in delphi,
make a DLL or ActiveX from that and use it in Python,
but I'm not allowed to ditribute these.

cheers,
Stef


From serverin2000 at yahoo.com  Mon Jul  6 04:11:27 2009
From: serverin2000 at yahoo.com (RAM)
Date: Mon, 6 Jul 2009 01:11:27 -0700 (PDT)
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
Message-ID: <d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>

On 5 July, 17:12, Tim Harig <user... at ilthio.net> wrote:
> On 2009-07-05, RAM <serverin2... at yahoo.com> wrote:
>
> > I need to start an external program and pass the keyboard events like
> > F1,Right arrow key etc to the program..I am trying to use the
> > subprocess module to invoke the external program. I am able to invoke
> > but not able to generate the keyboard events and pass them on to the
>
> catb.org/esr/faqs/smart-questions.html
>
> You have told us nothing about the environment where you are trying to
> accomplish this. ?GUI, CLI, Unix, Windows, etc? So I suggest that you
> checkout the curses getch functions. ?You can find them in the standard
> library documentation athttp://docs.python.org. ?You should also reference
> documentation for the C version in your systems man pages.

Hi Tim,

I am trying to do this on windows. My program(executable) has been
written in VC++ and when I run this program, I need to click on one
button on the program GUI i,e just I am entering "Enter key" on the
key board. But this needs manual process. So i need to write a python
script which invokes my program and pass "Enter key" event to my
program so that it runs without manual intervention.

Thank in advance for the help.

regards
Sreerama V


From david.m.cooke at gmail.com  Mon Jul  6 04:16:44 2009
From: david.m.cooke at gmail.com (David M. Cooke)
Date: Mon, 6 Jul 2009 08:16:44 +0000 (UTC)
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<4A50FDC6.1040604@v.loewis.de>
Message-ID: <loom.20090706T073723-420@post.gmane.org>

Martin v. L?wis <martin <at> v.loewis.de> writes:

> > This is a good test for Python implementation bottlenecks.  Run
> > that tokenizer on HTML, and see where the time goes.
> 
> I looked at it with cProfile, and the top function that comes up
> for a larger document (52k) is
> ...validator.HTMLConformanceChecker.__iter__.
[...]
> With this simple optimization, I get a 20% speedup on my test
> case. In my document, there are no attributes - the same changes
> should be made to attribute validation routines.
> 
> I don't think this has anything to do with the case statement.

I agree. I ran cProfile over just the tokenizer step; essentially

tokenizer = html5lib.tokenizer.HTMLStream(htmldata)
for tok in tokenizer:
    pass

It mostly *isn't* tokenizer.py that's taking the most time, it's
inputstream.py. (There is one exception:
tokenizer.py:HTMLStream.__init__ constructs a dictionary of states
each time -- this is unnecessary, replace all expressions like
self.states["attributeName"] with self.attributeNameState.)

I've done several optimisations -- I'll upload the patch to the
html5lib issue tracker. In particular,

* The .position property of EncodingBytes is used a lot. Every
self.position +=1 calls getPosition() and setPosition(). Another
getPosition() call is done in the self.currentByte property. Most of
these can be optimised away by using methods that move the position
and return the current byte.

* In HTMLInputStream, the current line number and column are updated
every time a new character is read with .char(). The current position
is *only* used in error reporting, so I reworked it to only calculate
the position when .position() is called, by keeping track of the
number of lines in previous read chunks, and computing the number of
lines to the current offset in the current chunk.

These give me about a 20% speedup.

This just illustrates that the first step in optimisation is profiling :D

As other posters have said, slurping the whole document into memory
and using a regexp-based parser (such as pyparsing) would likely give
you the largest speedups. If you want to keep the chunk- based
approach, you can still use regexp's, but you'd have to think about
matching on chunk boundaries. One way would be to guarantee a minimum
number of characters available, say 10 or 50 (unless end-of-file, of
course) -- long enough such that any *constant* string you'd want to
match like <![CDATA[ would fit inside that guaranteed length. Any
arbitrary-length tokens (such as attribute names and values) would be
matched, not with regexps like [a-z]+, but with [a-z]{1,10} (match
[a-z] from 1 to 10 times), and joining the individual matches together
to make one token.

Since html5lib has several implementations for several languages, it
may actually be worth it to generate lexers for each language from one
specification file.

Take care,
David M. Cooke <david.m.cooke at gmail.com>



From ldo at geek-central.gen.new_zealand  Mon Jul  6 04:29:04 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 20:29:04 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
Message-ID: <h2sckg$eng$2@lust.ihug.co.nz>

In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim Golden 
wrote:

> The difficulty here is knowing where to put such a warning.
> You obviously can't put it against the "++" operator as such
> because... there isn't one.

This bug is an epiphenomenon. :)



From wuwei23 at gmail.com  Mon Jul  6 04:30:03 2009
From: wuwei23 at gmail.com (alex23)
Date: Mon, 6 Jul 2009 01:30:03 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com> 
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
Message-ID: <19f3d19d-c4bc-4f94-8387-febe624245a2@p18g2000pra.googlegroups.com>

On Jul 6, 5:56?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Gabriel Genellina wrote:
> > In this case, a note in the documentation warning about the potential
> > confusion would be fine.
>
> The difficulty here is knowing where to put such a warning.
> You obviously can't put it against the "++" operator as such
> because... there isn't one. You could put it against the unary
> plus operator, but who's going to look there? :)

The problem is: where do you stop? If you're going to add something to
the documentation to address every expectation someone might hold
coming from another language, the docs are going to get pretty big.

I think a language should be intuitive within itself, but not be
required to be intuitable based on _other_ languages (unless, of
course, that's an objective of the language). If I expect something in
language-A to operate the same way as completely-unrelated-language-B,
I'd see that as a failing on my behalf, especially if I hadn't read
language-A's documentation first. I'm not adverse to one language
being _explained_ in terms of another, but would much prefer to see
those relegated to "Python for <x> programmers" articles rather than
in the main docs themselves.


From ldo at geek-central.gen.new_zealand  Mon Jul  6 04:32:34 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 20:32:34 +1200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <h2scr3$eng$3@lust.ihug.co.nz>

In message <4a4f91f9$0$1587$742ec2ed at news.sonic.net>, John Nagle wrote:

> ("It should be written in C" is not an acceptable answer.)

I don't see why not. State machines that have to process input byte by byte 
are well known to be impossible to implement efficiently in high-level 
languages. That's why lex/flex isn't worth using. Even GCC has been moving 
to hand-coded parsers, first the lexical analyzer, and more recently even 
for the syntax parser (getting rid of yacc/bison), certainly for C.



From clp2 at rebertia.com  Mon Jul  6 04:32:51 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 01:32:51 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2sckg$eng$2@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
Message-ID: <50697b2c0907060132w592ce54dt3c9392b764639bb2@mail.gmail.com>

On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim Golden
> wrote:
>
>> The difficulty here is knowing where to put such a warning.
>> You obviously can't put it against the "++" operator as such
>> because... there isn't one.
>
> This bug is an epiphenomenon. :)

Well, like I suggested, it /could/ be made an operator (or rather, a
lexer token) which just causes a compile/parse error.

Cheers,
Chris
-- 
http://blog.rebertia.com


From simon at brunningonline.net  Mon Jul  6 05:02:08 2009
From: simon at brunningonline.net (Simon Brunning)
Date: Mon, 6 Jul 2009 10:02:08 +0100
Subject: generation of keyboard events
In-Reply-To: <d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
	<d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
Message-ID: <8c7f10c60907060202v60c7ea0ct51749bbaf0f81bb6@mail.gmail.com>

2009/7/6 RAM <serverin2000 at yahoo.com>:

> I am trying to do this on windows. My program(executable) has been
> written in VC++ and when I run this program, I need to click on one
> button on the program GUI i,e just I am entering "Enter key" on the
> key board. But this needs manual process. So i need to write a python
> script which invokes my program and pass "Enter key" event to my
> program so that it runs without manual intervention.

Try <http://pywinauto.openqa.org/>.

-- 
Cheers,
Simon B.


From sjmachin at lexicon.net  Mon Jul  6 05:15:57 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 6 Jul 2009 02:15:57 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <2e02da2c-28d5-4ce5-9aa0-2827ba7110d3@12g2000pri.googlegroups.com>

On Jul 6, 12:32?pm, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> I wonder how many people have been tripped up by the fact that
>
> ? ? ++n
>
> and
>
> ? ? --n
>
> fail silently for numeric-valued n.

What fail? In Python, ++n and --n are fatuous expressions which
SUCCEED silently except for rare circiumstances e.g. --n will cause an
overflow exception on older CPython versions if isinstance(n, int) and
n == -sys.maxint - 1.



From vilya.harvey at gmail.com  Mon Jul  6 05:21:07 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Mon, 6 Jul 2009 10:21:07 +0100
Subject: Why is my code faster with append() in a loop than with a large 
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <6aef848f0907060221t6a44e10bga5a7798855779b5@mail.gmail.com>

2009/7/6 Xavier Ho <contact at xavierho.com>:
> Why is version B of the code faster than version A? (Only three lines
> different)

Here's a guess:

As the number you're testing gets larger, version A is creating very
big list. I'm not sure exactly how much overhead each list entry has
in python, but I guess it's at least 8 bytes: a 32-bit reference for
each list entry, and 32 bits to hold the int value (assuming a 32-bit
version of python). The solution you're looking for is a large 8 digit
number; let's say 80,000,000, for the sake of easy calculation. That
means, as you get close to the solution, you'll be trying to allocate
almost 640 Mb of memory for every number you're checking. That's going
to make the garbage collector work extremely hard. Also, depending on
how much memory your computer has free, you'll probably start hitting
virtual memory too, which will slow you down even further. Finally,
the reduce step has to process all 80,000,000 elements which is
clearly going to take a while.

Version b creates a list which is only as long as the largest prime
factor, so at worst the list size will be approx. sqrt(80,000,000),
which is approx. 8900 elements or approx. 72 Kb or memory - a much
more manageable size.

Hope that helps,

Vil.


From tjreedy at udel.edu  Mon Jul  6 05:36:27 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 05:36:27 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <h2sgiq$6ud$1@ger.gmane.org>

Gabriel Genellina wrote:
>
> In this case, a note in the documentation warning about the potential 
> confusion would be fine.

How would that help someone who does not read the doc?




From mooniitk at gmail.com  Mon Jul  6 05:55:26 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Mon, 6 Jul 2009 11:55:26 +0200
Subject: Tree structure consuming lot of memory
Message-ID: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>

Hi,

I am creating a tree data-structure in python; with nodes of the tree
created by a simple class :

class Node :
       def __init__(self , .... other attributes):
              # initialise the attributes here!!

But the problem is I am working with a huge tree (millions of nodes); and
each node is consuming much more memory than it should. After a little
analysis, I found out that in general it uses about 1.4 kb of memory for
each node!!
I will be grateful if someone could help me optimize the memory usage.
Thanks.

Regards,
Mayank


-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/a066fe29/attachment.html>

From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 05:58:21 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 09:58:21 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
Message-ID: <006da5a2$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 02:19:51 -0300, Gabriel Genellina wrote:

> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
> <steve at remove-this-cybersource.com.au> escribi?:
>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>
>>> I wonder how many people have been tripped up by the fact that
>>>
>>>     ++n
>>>
>>> and
>>>
>>>     --n
>>>
>>> fail silently for numeric-valued n.
>>
>> What do you mean, "fail silently"? They do exactly what you should
>> expect:
>>>>> ++5  # positive of a positive number is positive
>>
>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>> that are buggy, not Python.
> 
> Well, those expectations are taken seriously when new features are
> introduced into the language - and sometimes the feature is dismissed
> just because it would be confusing for some. If a += 1 works, expecting
> ++a to have the same meaning is very reasonable (for those coming from
> languages with a ++ operator, like C or Java) - more when ++a is a
> perfectly valid expression. If this issue isn't listed under the various
> "Python gotchas" articles, it should...

The fact that it isn't suggests strongly to me that it isn't that common 
a surprise even for Java and C programmers. This is the first time I've 
seen anyone raise it as an issue.

There are plenty of other languages other than Java and C. If we start 
listing every feature of Python that's different from some other 
language, we'll never end.

For what it's worth, Ruby appears to behave the same as Python:

$ irb
irb(main):001:0> n = 5
=> 5
irb(main):002:0> ++n
=> 5
irb(main):003:0> --n
=> 5
irb(main):004:0> -+n
=> -5



-- 
Steven


From clp2 at rebertia.com  Mon Jul  6 06:03:00 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 03:03:00 -0700
Subject: Tree structure consuming lot of memory
In-Reply-To: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
Message-ID: <50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>

On Mon, Jul 6, 2009 at 2:55 AM, mayank gupta<mooniitk at gmail.com> wrote:
> Hi,
>
> I am creating a tree data-structure in python; with nodes of the tree
> created by a simple class :
>
> class Node :
> ?????? def __init__(self , .... other attributes):
> ????????????? # initialise the attributes here!!
>
> But the problem is I am working with a huge tree (millions of nodes); and
> each node is consuming much more memory than it should. After a little
> analysis, I found out that in general it uses about 1.4 kb of memory for
> each node!!
> I will be grateful if someone could help me optimize the memory usage.

(1) Use __slots__ (see http://docs.python.org/reference/datamodel.html#slots)
(2) Use some data structure other than a tree
(3) Rewrite your Node/Tree implementation in C

Cheers,
Chris
-- 
http://blog.rebertia.com


From davea at dejaviewphoto.com  Mon Jul  6 06:09:46 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Mon, 06 Jul 2009 06:09:46 -0400
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <4A51CD6A.2010106@dejaviewphoto.com>

Xavier Ho wrote:
> (Here's a short version of the long version below if you don't want to
> read:)
>
> Why is version B of the code faster than version A? (Only three lines
> different)
>
> Version A: http://pastebin.com/f14561243
> Version B: http://pastebin.com/f1f657afc
>
> ------------------------------------------------
>
> I was doing the problems on Project Euler for practice with Python last
> night. Problem 12 was to find the value of the first triangular number that
> has over 500 divisors.
> =========================================================================================
>
> The sequence of triangle numbers is generated by adding the natural numbers.
> So the 7[image: ^(]th[image: )] triangle number would be 1 + 2 + 3 + 4 + 5 +
> 6 + 7 = 28. The first ten terms would be:
>
> 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
>
> Let us list the factors of the first seven triangle numbers:
>
> * 1*: 1
> * 3*: 1,3
> * 6*: 1,2,3,6
> *10*: 1,2,5,10
> *15*: 1,3,5,15
> *21*: 1,3,7,21
> *28*: 1,2,4,7,14,28
>
> We can see that 28 is the first triangle number to have over five divisors.
>
> What is the value of the first triangle number to have over five hundred
> divisors?
> =========================================================================================
>
> My initial code was to loop through from 1 to half the number and see which
> were divisors, and as I find them I store them in a list. That would have
> taken days.
>
> My second try was factorising the number each time, and count the divisors
> using the powers of each factor, plus 1, and multiply together.
> The code is here (Version A): http://pastebin.com/f14561243
>
> This worked, but it took overnight to compute. Before I went to bed a friend
> of mine caught me online, and apparently left me a working version under 8
> seconds with only 3 line difference.
> The code is here (Version B): http://pastebin.com/f1f657afc
>
> That was amazing. But I have no idea why his edit makes it so much faster. I
> did a test to see whether if append() was faster (which I doubted) than
> defining a list with a large size to begin with, and I was right:
> http://pastebin.com/f4b46d0db
> Which shows that appending is 40x slower, and was expected. But I still
> can't puzzle out why his use of appending in Version B was so much faster
> than mine.
>
> Any insights would be welcome. I'm going on a family trip, though, so my
> replies may delay.
>
> Best regards,
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
>   
Just by inspection, it would seem the bottleneck in your first version 
is that you return a huge list of nearly all zeroes, from factorize().  
This slows down countDivisors() a great deal.

It would probably save some time to not bother storing the zeroes in the 
list at all.  And it should help if you were to step through a list of 
primes, rather than trying every possible int.  Or at least constrain 
yourself to odd numbers (after the initial case of 2).

DaveA


From mooniitk at gmail.com  Mon Jul  6 06:12:06 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Mon, 6 Jul 2009 12:12:06 +0200
Subject: Tree structure consuming lot of memory
In-Reply-To: <50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>
Message-ID: <ff4d16090907060312n6df077capcce97ddd0786983@mail.gmail.com>

Thanks for the other possibilites. I would consider option (2) and (3) to
improve my code.

But out of curiosity, I would still like to know why does an object of a
Python-class consume "so" much of memory (1.4 kb), and this memory usage has
nothing to do with its attributes.

Thanks

Regards.

On Mon, Jul 6, 2009 at 12:03 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Mon, Jul 6, 2009 at 2:55 AM, mayank gupta<mooniitk at gmail.com> wrote:
> > Hi,
> >
> > I am creating a tree data-structure in python; with nodes of the tree
> > created by a simple class :
> >
> > class Node :
> >        def __init__(self , .... other attributes):
> >               # initialise the attributes here!!
> >
> > But the problem is I am working with a huge tree (millions of nodes); and
> > each node is consuming much more memory than it should. After a little
> > analysis, I found out that in general it uses about 1.4 kb of memory for
> > each node!!
> > I will be grateful if someone could help me optimize the memory usage.
>
> (1) Use __slots__ (see
> http://docs.python.org/reference/datamodel.html#slots)
> (2) Use some data structure other than a tree
> (3) Rewrite your Node/Tree implementation in C
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>



-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/a1061b4a/attachment.html>

From p.f.moore at gmail.com  Mon Jul  6 08:05:02 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Mon, 6 Jul 2009 13:05:02 +0100
Subject: Opening a SQLite database in readonly mode
Message-ID: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>

The SQLite documentation mentions a flag, SQLITE_OPEN_READONLY, to
open a database read only. I can't find any equivalent documented in
the Python standard library documentation for the sqlite3 module (or,
for that matter, on the pysqlite library's website).

Is it possible to open a sqlite database in readonly mode, in Python?

Thanks,
Paul.


From mail at microcorp.co.za  Mon Jul  6 08:12:42 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Mon, 6 Jul 2009 14:12:42 +0200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com><op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<h2sgiq$6ud$1@ger.gmane.org>
Message-ID: <00df01c9fe33$10c36d80$0d00a8c0@Hendrik>

"Terry Reedy" <t...j at ..el.edu> wrote:

> Gabriel Genellina wrote:
> >
> > In this case, a note in the documentation warning about the potential 
> > confusion would be fine.
> 
> How would that help someone who does not read the doc?

It obviously won't.

All it will do, is that it will enable people on this group,
who may read the manual, to tell people who complain,
to RTFM.

 I agree that it would be a good idea to make it an 
error, or a warning - "this might not do what you
think it does", or an "are you sure?" exception.

  :-)

- Hendrik





From contact at xavierho.com  Mon Jul  6 08:12:58 2009
From: contact at xavierho.com (Xavier Ho)
Date: Mon, 6 Jul 2009 20:12:58 +0800
Subject: Why is my code faster with append() in a loop than with a large 
	list?
In-Reply-To: <4A51CD6A.2010106@dejaviewphoto.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<4A51CD6A.2010106@dejaviewphoto.com>
Message-ID: <2d56febf0907060512m794c2468sfa01cf332df3167a@mail.gmail.com>

Thanks for the response all, I finally got my 'net working on the mountains,
and I think your reasons are quite sound. I'll keep that in mind for the
future.

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Mon, Jul 6, 2009 at 6:09 PM, Dave Angel <davea at dejaviewphoto.com> wrote:

> Xavier Ho wrote:
>
>> (Here's a short version of the long version below if you don't want to
>> read:)
>>
>> Why is version B of the code faster than version A? (Only three lines
>> different)
>>
>> Version A: http://pastebin.com/f14561243
>> Version B: http://pastebin.com/f1f657afc
>>
>> ------------------------------------------------
>>
>> I was doing the problems on Project Euler for practice with Python last
>> night. Problem 12 was to find the value of the first triangular number
>> that
>> has over 500 divisors.
>>
>> =========================================================================================
>>
>> The sequence of triangle numbers is generated by adding the natural
>> numbers.
>> So the 7[image: ^(]th[image: )] triangle number would be 1 + 2 + 3 + 4 + 5
>> +
>>
>> 6 + 7 = 28. The first ten terms would be:
>>
>> 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
>>
>> Let us list the factors of the first seven triangle numbers:
>>
>> * 1*: 1
>> * 3*: 1,3
>> * 6*: 1,2,3,6
>> *10*: 1,2,5,10
>> *15*: 1,3,5,15
>> *21*: 1,3,7,21
>> *28*: 1,2,4,7,14,28
>>
>> We can see that 28 is the first triangle number to have over five
>> divisors.
>>
>> What is the value of the first triangle number to have over five hundred
>> divisors?
>>
>> =========================================================================================
>>
>> My initial code was to loop through from 1 to half the number and see
>> which
>> were divisors, and as I find them I store them in a list. That would have
>> taken days.
>>
>> My second try was factorising the number each time, and count the divisors
>> using the powers of each factor, plus 1, and multiply together.
>> The code is here (Version A): http://pastebin.com/f14561243
>>
>> This worked, but it took overnight to compute. Before I went to bed a
>> friend
>> of mine caught me online, and apparently left me a working version under 8
>> seconds with only 3 line difference.
>> The code is here (Version B): http://pastebin.com/f1f657afc
>>
>> That was amazing. But I have no idea why his edit makes it so much faster.
>> I
>> did a test to see whether if append() was faster (which I doubted) than
>> defining a list with a large size to begin with, and I was right:
>> http://pastebin.com/f4b46d0db
>> Which shows that appending is 40x slower, and was expected. But I still
>> can't puzzle out why his use of appending in Version B was so much faster
>> than mine.
>>
>> Any insights would be welcome. I'm going on a family trip, though, so my
>> replies may delay.
>>
>> Best regards,
>>
>> Ching-Yun "Xavier" Ho, Technical Artist
>>
>> Contact Information
>> Mobile: (+61) 04 3335 4748
>> Skype ID: SpaXe85
>> Email: contact at xavierho.com
>> Website: http://xavierho.com/
>>
>>
>>
> Just by inspection, it would seem the bottleneck in your first version is
> that you return a huge list of nearly all zeroes, from factorize().  This
> slows down countDivisors() a great deal.
>
> It would probably save some time to not bother storing the zeroes in the
> list at all.  And it should help if you were to step through a list of
> primes, rather than trying every possible int.  Or at least constrain
> yourself to odd numbers (after the initial case of 2).
>
> DaveA
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/2a336b8d/attachment.html>

From pm567426 at gmail.com  Mon Jul  6 08:24:43 2009
From: pm567426 at gmail.com (Pedram)
Date: Mon, 6 Jul 2009 05:24:43 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
Message-ID: <b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com>

OK, fine, I read longobject.c at last! :)
I found that longobject is a structure like this:

struct _longobject {
    struct _object *_ob_next;
    struct _object *_ob_prev;
    Py_ssize_t ob_refcnt;
    struct _typeobject *ob_type;
    digit ob_digit[1];
}

And a digit is a 15-item array of C's unsigned short integers.
Am I right? Or I missed something! Is this structure is constant in
all environments (Linux, Windows, Mobiles, etc.)?


From jeanmichel at sequans.com  Mon Jul  6 08:32:10 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 06 Jul 2009 14:32:10 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2nqpf$d91$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
Message-ID: <4A51EECA.10509@sequans.com>

kj wrote:
>  I've rewritten it like this:
>
>     sense = cmp(func(hi), func(lo))
>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>
> Thanks for your feedback!
>
> kj
>   

As already said before, unlike other languages, sense in english does 
**not** mean direction. You should rewrite this part using a better 
name. Wrong informations are far worse than no information at all.

JM


From Scott.Daniels at Acm.Org  Mon Jul  6 08:33:02 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 05:33:02 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <mailman.2673.1246866666.8015.python-list@python.org>
References: <h2l36k$q5l$1@reader1.panix.com>	<f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
	<mailman.2673.1246866666.8015.python-list@python.org>
Message-ID: <fMKdnf0dlOXTcMzXnZ2dnUVZ_t2dnZ2d@pdx.net>

Andre Engels wrote:
> On Mon, Jul 6, 2009 at 9:44 AM, Martin Vilcans<martin at librador.com> wrote:
>> On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
>>> I'm will be teaching a programming class to novices, and I've run
>>> into a clear conflict between two of the principles I'd like to
>>> teach: code clarity vs. code reuse.  I'd love your opinion about
>>> it.
>> In general, code clarity is more important than reusability.
>> Unfortunately, many novice programmers have the opposite impression. I
>> have seen too much convoluted code written by beginners who try to
>> make the code generic. Writing simple, clear, to-the-point code is
>> hard enough as it is, even when not aiming at making it reusable.
>>
>> If in the future you see an opportunity to reuse the code, then and
>> only then is the time to make it generic.
> 
> Not just that, when you actually get to that point, making simple and
> clear code generic is often easier than making
> complicated-and-supposedly-generic code that little bit more generic
> that you need.

First, a quote which took me a bit to find:
     Thomas William K?rner paraphrasing Polya and Svego
     in A Companion to Analysis:
         Recalling that 'once is a trick, twice is a method,
         thrice is a theorem, and four times a theory,' we
         seek to codify this insight.

Let us apply this insight:
     Suppose in writing code, we pretty much go with that.
A method is something you notice, a theorem is a function, and
a theory is a generalized function.

Even though we like DRY ("don't repeat yourself") as a maxim, let
it go the first time and wait until you see the pattern (a possible
function).  I'd go with a function first, a pair of functions, and
only then look to abstracting the function.

--Scott David Daniels
Scott.Daniels at Acm.Org


From Scott.Daniels at Acm.Org  Mon Jul  6 08:47:18 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 05:47:18 -0700
Subject: Creating alot of class instances?
In-Reply-To: <006d4e86$0$9711$c3e8da3@news.astraweb.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>	<mailman.2652.1246830168.8015.python-list@python.org>	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <comdnVhXl4M6bczXnZ2dnUVZ_g2dnZ2d@pdx.net>

Steven D'Aprano wrote:
> ... That's the Wrong Way to do it --
> you're using a screwdriver to hammer a nail....

Don't knock tool abuse (though I agree with you here).
Sometimes tool abuse can produce good results.  For
example, using hammers to drive screws for temporary
strong holds led to making better nails.

--Scott David Daniels
Scott.Daniels at Acm.Org


From ronn.ross at gmail.com  Mon Jul  6 08:47:30 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Mon, 6 Jul 2009 08:47:30 -0400
Subject: VirtualEnv
Message-ID: <9c8c445f0907060547g5a279821n4cd31efe9231887b@mail.gmail.com>

I'm attempting to write a bootstrap script for virtualenv. I just want to do
a couple of easy_install's after the environment is created. It was fairly
easy to create the script, but I can't figure out how to implement it. The
documentation was not of much help. Can someone please point me in the right
direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/e9494afe/attachment.html>

From jeanmichel at sequans.com  Mon Jul  6 08:54:03 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 06 Jul 2009 14:54:03 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <006201c9fd48$666d94e0$0d00a8c0@Hendrik>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<006201c9fd48$666d94e0$0d00a8c0@Hendrik>
Message-ID: <4A51F3EB.1080509@sequans.com>


> protocol = {"start":initialiser,"hunt":hunter,"classify":classifier,....other
> states}
>
> def state_machine():
>     next_step = protocol["start"]()
>     while True:
>         next_step = protocol[next_step]()
>
>   
Woot ! I'll keep this one in my mind, while I may not be that concerned 
by speed unlike the OP, I still find this way of doing very simple and 
so intuitive (one will successfully argue how I was not figuring this 
out by myself if it was so intuitive).
Anyway I wanted to participated to this thread, as soon as I saw 'due to 
python limitations' in the title, I foretold a hell of a thread ! This 
is just provocation ! :-)

JM


From pdpinheiro at gmail.com  Mon Jul  6 09:38:13 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Mon, 6 Jul 2009 06:38:13 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com><op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<h2sgiq$6ud$1@ger.gmane.org>
	<mailman.2687.1246882531.8015.python-list@python.org>
Message-ID: <bdfa2d84-e4ed-4197-8bf7-83dc28d131e7@26g2000yqk.googlegroups.com>

On Jul 6, 1:12?pm, "Hendrik van Rooyen" <m... at microcorp.co.za> wrote:
> "Terry Reedy" <t...j at ..el.edu> wrote:
> > Gabriel Genellina wrote:
>
> > > In this case, a note in the documentation warning about the potential
> > > confusion would be fine.
>
> > How would that help someone who does not read the doc?
>
> It obviously won't.
>
> All it will do, is that it will enable people on this group,
> who may read the manual, to tell people who complain,
> to RTFM.
>
> ?I agree that it would be a good idea to make it an
> error, or a warning - "this might not do what you
> think it does", or an "are you sure?" exception.
>
> ? :-)
>
> - Hendrik

I dunno. Specifically recognizing (and emitting code code for) a token
that's not actually part of the language because people coming from
other languages think it exists seems like the start of a fustercluck.


From dickinsm at gmail.com  Mon Jul  6 09:46:05 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Mon, 6 Jul 2009 06:46:05 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com>
Message-ID: <088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com>

On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
> OK, fine, I read longobject.c at last! :)
> I found that longobject is a structure like this:
>
> struct _longobject {
> ? ? struct _object *_ob_next;
> ? ? struct _object *_ob_prev;

For current CPython, these two fields are only present in debug
builds;  for a normal build they won't exist.

> ? ? Py_ssize_t ob_refcnt;
> ? ? struct _typeobject *ob_type;

You're missing an important field here (see the definition of
PyObject_VAR_HEAD):

    Py_ssize_t ob_size; /* Number of items in variable part */

For the current implementation of Python longs, the absolute value of
this field gives the number of digits in the long;  the sign gives the
sign of the long (0L is represented with zero digits).

> ? ? digit ob_digit[1];

Right.  This is an example of the so-called 'struct hack' in C; it
looks as though there's just a single digit, but what's intended here
is that there's an array of digits tacked onto the end of the struct;
for any given PyLongObject, the size of this array is determined at
runtime.  (C99 allows you to write this as simply ob_digit[], but not
all compilers support this yet.)

> }

> And a digit is a 15-item array of C's unsigned short integers.

No: a digit is a single unsigned short, which is used to store 15 bits
of the Python long.  Python longs are stored in sign-magnitude format,
in base 2**15.  So each of the base 2**15 'digits' is an integer in
the range [0, 32767).  The unsigned short type is used to store those
digits.

Exception: for Python 2.7+ or Python 3.1+, on 64-bit machines, Python
longs are stored in base 2**30 instead of base 2**15, using a 32-bit
unsigned integer type in place of unsigned short.

> Is this structure is constant in
> all environments (Linux, Windows, Mobiles, etc.)?

I think it would be dangerous to rely on this struct staying constant,
even just for CPython.  It's entirely possible that the representation
of Python longs could change in Python 2.8 or 3.2.  You should use the
public, documented C-API whenever possible.

Mark


From philip at semanchuk.com  Mon Jul  6 09:51:58 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 09:51:58 -0400
Subject: How to map size_t using ctypes?
Message-ID: <A30412CC-0922-49EF-878F-D1CD344B37CB@semanchuk.com>

Hi all,
I can't figure out how to map a C variable of size_t via Python's  
ctypes module. Let's say I have a C function like this:

void populate_big_array(double *the_array, size_t element_count) {...}

How would I pass parameter 2? A long (or ulong) will (probably) work  
(on most platforms), but I like my code to be more robust than that.  
Furthermore, this is scientific code and it's entirely possible that  
someone will want to pass a huge array with more elements than can be  
described by a 32-bit long.


Suggestions appreciated.

Thanks
Philip


From Scott.Daniels at Acm.Org  Mon Jul  6 09:59:44 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 06:59:44 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <h2s5rm$m95$01$1@news.t-online.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org>
	<UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>
	<h2s5rm$m95$01$1@news.t-online.com>
Message-ID: <4A520350.9000806@Acm.Org>

Peter Otten wrote:
> Scott David Daniels wrote:
> 
>> Scott David Daniels wrote:
> 
>>      t = timeit.Timer('sum(part[:-1]==part[1:])',
>>                       'from __main__ import part')
> 
> What happens if you calculate the sum in numpy? Try
> 
> t = timeit.Timer('(part[:-1]==part[1:]).sum()',
>                  'from __main__ import part')

Good idea, I hadn't thought of adding numpy bools.
     (part[:-1]==part[1:]).sum()
is only a slight improvement over
     len(part[part[:-1]==part[1:]])
when there are few elements, but it is almost twice
as fast when there are a lot (reflecting the work
of allocating and copying).

 >>> import numpy
 >>> import timeit
 >>> original = numpy.random.normal(0, 100, (1000, 1000)).astype(int)
 >>> data = original.flatten()
 >>> data.sort()
 >>> t = timeit.Timer('sum(part[:-1]==part[1:])',
                      'from __main__ import part')
 >>> u = timeit.Timer('len(part[part[:-1]==part[1:]])',
                      'from __main__ import part')
 >>> v = timeit.Timer('(part[:-1]==part[1:]).sum()',
                      'from __main__ import part')

 >>> part = data[::100]
 >>> (part[:-1]==part[1:]).sum()
9390
 >>> t.repeat(3, 10)
[0.56368281443587875, 0.55615057220961717, 0.55465764503594528]
 >>> u.repeat(3, 1000)
[0.89576580263690175, 0.89276374511291579, 0.8937328626963108]
 >>> v.repeat(3, 1000)
[0.24798598704592223, 0.24715431709898894, 0.24498979618920202]
 >>>
 >>> part = original.flatten()[::100]
 >>> (part[:-1]==part[1:]).sum()
27
 >>> t.repeat(3, 10)
[0.57576898739921489, 0.56410158274297828, 0.56988248506445416]
 >>> u.repeat(3, 1000)
[0.27312186325366383, 0.27315007913011868, 0.27214492344683094]
 >>> v.repeat(3, 1000)
[0.28410342655297427, 0.28374053126867693, 0.28318990262732768]
 >>>

Net result: go back to former definition of candidates (a number,
not the actual entries), but calculate that number as matches.sum(),
not len(part[matches]).

Now the latest version of this (compressed) code:
 >     ...
 >     sampled = data[::stride]
 >     matches = sampled[:-1] == sampled[1:]
 >     candidates = sum(matches) # count identified matches
 >     while candidates > N * 10: # 10 -- heuristic
 >         stride *= 2 # # heuristic increase
 >         sampled = data[::stride]
 >         matches = sampled[:-1] == sampled[1:]
 >         candidates = sum(matches)
 >     while candidates < N * 3: # heuristic slop for long runs
 >         stride //= 2 # heuristic decrease
 >         sampled = data[::stride]
 >         matches = sampled[:-1] == sampled[1:]
 >         candidates = sum(matches)
 >     former = None
 >     past = 0
 >     for value in sampled[matches]:
 >         ...
is:
       ...
       sampled = data[::stride]
       matches = sampled[:-1] == sampled[1:]
       candidates = matches.sum() # count identified matches
       while candidates > N * 10: # 10 -- heuristic
           stride *= 2 # # heuristic increase
           sampled = data[::stride]
           matches = sampled[:-1] == sampled[1:]
           candidates = matches.sum()
       while candidates < N * 3: # heuristic slop for long runs
           stride //= 2 # heuristic decrease
           sampled = data[::stride]
           matches = sampled[:-1] == sampled[1:]
           candidates = matches.sum()
       former = None
       past = 0
       for value in sampled[matches]:
           ...

Now I think I can let this problem go, esp. since it was
mclovin's problem in the first place.

--Scott David Daniels
Scott.Daniels at Acm.Org


From dickinsm at gmail.com  Mon Jul  6 10:01:42 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Mon, 6 Jul 2009 07:01:42 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>

On Jul 6, 3:32?am, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> I wonder how many people have been tripped up by the fact that
>
> ? ? ++n
>
> and
>
> ? ? --n
>
> fail silently for numeric-valued n.

Recent python-ideas discussion on this subject:

http://mail.python.org/pipermail/python-ideas/2009-March/003741.html

Mark


From mail at microcorp.co.za  Mon Jul  6 10:04:30 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Mon, 6 Jul 2009 16:04:30 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<006201c9fd48$666d94e0$0d00a8c0@Hendrik>
	<4A51F3EB.1080509@sequans.com>
Message-ID: <000901c9fe42$b026cfc0$0d00a8c0@Hendrik>

"Jean-Michel Pichavant" <jeanmichel at s....ns.com> wrote:

> Woot ! I'll keep this one in my mind, while I may not be that concerned 
> by speed unlike the OP, I still find this way of doing very simple and 
> so intuitive (one will successfully argue how I was not figuring this 
> out by myself if it was so intuitive).
> Anyway I wanted to participated to this thread, as soon as I saw 'due to 
> python limitations' in the title, I foretold a hell of a thread ! This 
> is just provocation ! :-)

The OP was not being provocative - he has a real problem, and the
code he is complaining about already does more or less what my
snippet showed, as I rushed in where angels fear to tread...

The bit that was not clearly shown in what I proposed, is that you
should stay in the individual states, testing for the reasons for the
state transitions, until it is time to change - so there is a while loop
in each of the individual states too.  It becomes a terribly big structure
if you have a lot of states, it duplicates a lot of tests across the different
states, and it is very awkward if the states nest.

Have a look at the one without the dict too - it is even faster as it
avoids the dict lookup.

That, however, is a bit like assembler code, as it kind of "jumps" 
from state to state, and there is no central thing to show what does,
and what does not, belong together, as there is no dict.  Not an easy
beast to fix if it's big and it's wrong.

- Hendrik





From "sandrodll[remove]" at googlemail.com  Mon Jul  6 10:21:01 2009
From: "sandrodll[remove]" at googlemail.com (gialloporpora)
Date: Mon, 06 Jul 2009 16:21:01 +0200
Subject: Help to find a regular expression to parse po file
Message-ID: <4A52084D.1010900@googlemail.com>

Hi all,
I would like to extract string from a PO file. To do this I have created 
a little python function to parse po file and extract string:

import re
regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
m=r.findall(s)

where s is a po file like this:

msgctxt "write ubiquity commands.description"
msgid "Takes you to the Ubiquity <a 
href=\"chrome://ubiquity/content/editor.html\">command editor</a> page."
msgstr "Apre l'<a href=\"chrome://ubiquity/content/editor.html\">editor 
dei comandi</a> di Ubiquity."


#. list ubiquity commands command:
#. use | to separate multiple name values:
msgctxt "list ubiquity commands.names"
msgid "list ubiquity commands"
msgstr "elenco comandi disponibili"

msgctxt "list ubiquity commands.description"
msgid "Opens <a href=\"chrome://ubiquity/content/cmdlist.html\">the 
list</a>\n"
"      of all Ubiquity commands available and what they all do."
msgstr "Apre una <a 
href=\"chrome://ubiquity/content/cmdlist.html\">pagina</a>\n"
"      in cui sono elencati tutti i comandi disponibili e per ognuno 
viene spiegato in breve a cosa serve."



#. change ubiquity settings command:
#. use | to separate multiple name values:
msgctxt "change ubiquity settings.names"
msgid "change ubiquity settings|change ubiquity preferences|change 
ubiquity skin"
msgstr "modifica impostazioni di ubiquity|modifica preferenze di 
ubiquity|modifica tema di ubiquity"

msgctxt "change ubiquity settings.description"
msgid "Takes you to the <a 
href=\"chrome://ubiquity/content/settings.html\">settings</a> page,\n"
"      where you can change your skin, key combinations, etc."
msgstr "Apre la pagina  <a 
href=\"chrome://ubiquity/content/settings.html\">delle impostazioni</a> 
di Ubiquity,\n"
"     dalla quale ?? possibile modificare la combinazione da tastiera 
utilizzata per richiamare Ubiquity, il tema, ecc."



but, obviusly,  with the code above the  last string is not matched. If 
I use re.DOTALL to match also new line character it not works because it 
match the entire file, I would like to stop the matching when "msgstr" 
is found.

regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n\\n",re.DOTALL)

is it possible or not ?






From python at mrabarnett.plus.com  Mon Jul  6 10:22:23 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 15:22:23 +0100
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <4A51CD6A.2010106@dejaviewphoto.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<4A51CD6A.2010106@dejaviewphoto.com>
Message-ID: <4A52089F.7020301@mrabarnett.plus.com>

Dave Angel wrote:
[snip]
> It would probably save some time to not bother storing the zeroes in the 
> list at all.  And it should help if you were to step through a list of 
> primes, rather than trying every possible int.  Or at least constrain 
> yourself to odd numbers (after the initial case of 2).
> 
Or stop looking for more factors when you've passed the square root of
num. I don't know what effect there'll be on the time if you recalculate
the square root when num changes (expensive calculation vs smaller
search space).


From rhodri at wildebst.demon.co.uk  Mon Jul  6 11:00:59 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Mon, 06 Jul 2009 16:00:59 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <006da5a2$0$9711$c3e8da3@news.astraweb.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <op.uwninxtza8ncjz@gnudebst>

On Mon, 06 Jul 2009 10:58:21 +0100, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> wrote:

> On Mon, 06 Jul 2009 02:19:51 -0300, Gabriel Genellina wrote:
>
>> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
>> <steve at remove-this-cybersource.com.au> escribi?:
>>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>>
>>>> I wonder how many people have been tripped up by the fact that
>>>>
>>>>     ++n
>>>>
>>>> and
>>>>
>>>>     --n
>>>>
>>>> fail silently for numeric-valued n.
>>>
>>> What do you mean, "fail silently"? They do exactly what you should
>>> expect:
>>>>>> ++5  # positive of a positive number is positive
>>>
>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>> that are buggy, not Python.
>>
>> Well, those expectations are taken seriously when new features are
>> introduced into the language - and sometimes the feature is dismissed
>> just because it would be confusing for some. If a += 1 works, expecting
>> ++a to have the same meaning is very reasonable (for those coming from
>> languages with a ++ operator, like C or Java) - more when ++a is a
>> perfectly valid expression. If this issue isn't listed under the various
>> "Python gotchas" articles, it should...
>
> The fact that it isn't suggests strongly to me that it isn't that common
> a surprise even for Java and C programmers. This is the first time I've
> seen anyone raise it as an issue.

Indeed, arguably it's a bug for C compilers to fail to find the valid
parsing of "++5" as "+(+5)".  All I can say is that I've never even
accidentally typed that in twenty years of C programming.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From h.b.furuseth at usit.uio.no  Mon Jul  6 11:04:06 2009
From: h.b.furuseth at usit.uio.no (Hallvard B Furuseth)
Date: Mon, 06 Jul 2009 17:04:06 +0200
Subject: Help to find a regular expression to parse po file
References: <4A52084D.1010900@googlemail.com>
Message-ID: <hbf.20090706bevs@bombur.uio.no>

gialloporpora writes:
> I would like to extract string from a PO file. To do this I have created
> a little python function to parse po file and extract string:
>
> import re
> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
> m=r.findall(s)

I don't know the syntax of a po file, but this works for the
snippet you posted:

arg_re = r'"[^\\\"]*(?:\\.[^\\\"]*)*"'
arg_re = '%s(?:\s+%s)*' % (arg_re, arg_re)
find_re = re.compile(
    r'^msgid\s+(' + arg_re + ')\s*\nmsgstr\s+(' + arg_re + ')\s*\n', re.M)

However, can \ quote a newline? If so, replace \\. with \\[\s\S] or
something.
Can there be other keywords between msgid and msgstr?  If so,
add something like (?:\w+\s+<arg_re>\s*\n)*? between them.
Can msgstr come before msgid? If so, forget using a single regexp.
Anything else to the syntax to look out for?  Single quotes, maybe?

Is it a problem if the regexp isn't quite right and doesn't match all
cases, yet doesn't report an error when that happens?

All in all, it may be a bad idea to sqeeze this into a single regexp.
It gets ugly real fast.  Might be better to parse the file in a more
regular way, maybe using regexps just to extract each (keyword, "value")
pair.

-- 
Hallvard


From james at agentultra.com  Mon Jul  6 11:06:50 2009
From: james at agentultra.com (J Kenneth King)
Date: Mon, 06 Jul 2009 11:06:50 -0400
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<mailman.2639.1246802753.8015.python-list@python.org>
	<h2qfl7$k87$1@panix3.panix.com>
Message-ID: <85prcdetpx.fsf@agentultra.com>

aahz at pythoncraft.com (Aahz) writes:

> In article <mailman.2639.1246802753.8015.python-list at python.org>,
> Hendrik van Rooyen <mail at microcorp.co.za> wrote:
>>
>>But wait - maybe if he passes an iterator around - the equivalent of
>>for char in input_stream...  Still no good though, unless the next call
>>to the iterator is faster than an ordinary python call.
>
> Calls to iterators created by generators are indeed faster than an
> ordinary Python call, because the stack frame is already mostly set up.

I think Beazely demonstrated this in his talk on using the python 2.5
co-routines to setup an xml parser.  I believe he benchmarked it roughly
and the initial results were rather impressive.

http://www.dabeaz.com/coroutines/


From python at mrabarnett.plus.com  Mon Jul  6 11:12:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 16:12:18 +0100
Subject: Help to find a regular expression to parse po file
In-Reply-To: <4A52084D.1010900@googlemail.com>
References: <4A52084D.1010900@googlemail.com>
Message-ID: <4A521452.4090405@mrabarnett.plus.com>

gialloporpora wrote:
> Hi all,
> I would like to extract string from a PO file. To do this I have created 
> a little python function to parse po file and extract string:
> 
> import re
> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
> m=r.findall(s)
> 
> where s is a po file like this:
> 
> msgctxt "write ubiquity commands.description"
> msgid "Takes you to the Ubiquity <a 
> href=\"chrome://ubiquity/content/editor.html\">command editor</a> page."
> msgstr "Apre l'<a href=\"chrome://ubiquity/content/editor.html\">editor 
> dei comandi</a> di Ubiquity."
> 
> 
> #. list ubiquity commands command:
> #. use | to separate multiple name values:
> msgctxt "list ubiquity commands.names"
> msgid "list ubiquity commands"
> msgstr "elenco comandi disponibili"
> 
> msgctxt "list ubiquity commands.description"
> msgid "Opens <a href=\"chrome://ubiquity/content/cmdlist.html\">the 
> list</a>\n"
> "      of all Ubiquity commands available and what they all do."
> msgstr "Apre una <a 
> href=\"chrome://ubiquity/content/cmdlist.html\">pagina</a>\n"
> "      in cui sono elencati tutti i comandi disponibili e per ognuno 
> viene spiegato in breve a cosa serve."
> 
> 
> 
> #. change ubiquity settings command:
> #. use | to separate multiple name values:
> msgctxt "change ubiquity settings.names"
> msgid "change ubiquity settings|change ubiquity preferences|change 
> ubiquity skin"
> msgstr "modifica impostazioni di ubiquity|modifica preferenze di 
> ubiquity|modifica tema di ubiquity"
> 
> msgctxt "change ubiquity settings.description"
> msgid "Takes you to the <a 
> href=\"chrome://ubiquity/content/settings.html\">settings</a> page,\n"
> "      where you can change your skin, key combinations, etc."
> msgstr "Apre la pagina  <a 
> href=\"chrome://ubiquity/content/settings.html\">delle impostazioni</a> 
> di Ubiquity,\n"
> "     dalla quale ?? possibile modificare la combinazione da tastiera 
> utilizzata per richiamare Ubiquity, il tema, ecc."
> 
> 
> 
> but, obviusly,  with the code above the  last string is not matched. If 
> I use re.DOTALL to match also new line character it not works because it 
> match the entire file, I would like to stop the matching when "msgstr" 
> is found.
> 
> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n\\n",re.DOTALL)
> 
> is it possible or not ?
> 
You could try:

regex = re.compile(r"msgid (.*(?:\n".*")*)\nmsgstr (.*(?:\n".*")*)$")

and then, if necessary, tidy what you get.


From pm567426 at gmail.com  Mon Jul  6 11:13:00 2009
From: pm567426 at gmail.com (Pedram)
Date: Mon, 6 Jul 2009 08:13:00 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com> 
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com>
Message-ID: <173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com>

Hello Mr. Dickinson. Glad to see you again :)

On Jul 6, 5:46?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
>
> > OK, fine, I read longobject.c at last! :)
> > I found that longobject is a structure like this:
>
> > struct _longobject {
> > ? ? struct _object *_ob_next;
> > ? ? struct _object *_ob_prev;
>
> For current CPython, these two fields are only present in debug
> builds; ?for a normal build they won't exist.

I couldn't understand the difference between them. What are debug
build and normal build themselves? And You mean in debug build
PyLongObject is a doubly-linked-list but in normal build it is just an
array (Or if not how it'll store in this mode)?

> > ? ? Py_ssize_t ob_refcnt;
> > ? ? struct _typeobject *ob_type;
>
> You're missing an important field here (see the definition of
> PyObject_VAR_HEAD):
>
> ? ? Py_ssize_t ob_size; /* Number of items in variable part */
>
> For the current implementation of Python longs, the absolute value of
> this field gives the number of digits in the long; ?the sign gives the
> sign of the long (0L is represented with zero digits).

Oh, you're right. I missed that. Thanks :)

> > ? ? digit ob_digit[1];
>
> Right. ?This is an example of the so-called 'struct hack' in C; it
> looks as though there's just a single digit, but what's intended here
> is that there's an array of digits tacked onto the end of the struct;
> for any given PyLongObject, the size of this array is determined at
> runtime. ?(C99 allows you to write this as simply ob_digit[], but not
> all compilers support this yet.)

WOW! I didn't know anything about 'struct hacks'! I read about them
and they were very wonderful. Thanks for your point. :)

> > }
> > And a digit is a 15-item array of C's unsigned short integers.
>
> No: a digit is a single unsigned short, which is used to store 15 bits
> of the Python long. ?Python longs are stored in sign-magnitude format,
> in base 2**15. ?So each of the base 2**15 'digits' is an integer in
> the range [0, 32767). ?The unsigned short type is used to store those
> digits.
>
> Exception: for Python 2.7+ or Python 3.1+, on 64-bit machines, Python
> longs are stored in base 2**30 instead of base 2**15, using a 32-bit
> unsigned integer type in place of unsigned short.
>
> > Is this structure is constant in
> > all environments (Linux, Windows, Mobiles, etc.)?
>
> I think it would be dangerous to rely on this struct staying constant,
> even just for CPython. ?It's entirely possible that the representation
> of Python longs could change in Python 2.8 or 3.2. ?You should use the
> public, documented C-API whenever possible.
>
> Mark

Thank you a lot Mark :)


From piet at cs.uu.nl  Mon Jul  6 11:15:47 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 06 Jul 2009 17:15:47 +0200
Subject: Why is my code faster with append() in a loop than with a large
	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
Message-ID: <m2r5wtetb0.fsf@cs.uu.nl>

>>>>> Dave Angel <davea at dejaviewphoto.com> (DA) wrote:

>DA> It would probably save some time to not bother storing the zeroes in the
>DA> list at all.  And it should help if you were to step through a list of
>DA> primes, rather than trying every possible int.  Or at least constrain
>DA> yourself to odd numbers (after the initial case of 2).

The first and the last save a constant factor (slightly less than 2):

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    factor = 2
    while num > 1:
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            powers.append(power+1)
        factor += 1
    return powers

...
    return reduce(mul, powers)

or to skip the odd factors:

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    factor = 2
    while num > 1:
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            powers.append(power+1)
        factor = 3 if factor == 2 else factor + 2
    return powers

This can be slightly optimised by taking factor 2 out of the loop.

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    power = 0
    while num % 2 == 0:
        power += 1
        num /= 2
    if power > 0:
        powers.append(power+1)
    factor = 3
    while num > 1:
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            powers.append(power+1)
        factor += 2
    return powers

To restrict the search to primes you would have to use a
sieve of Eratosthenes or something similar.
My first attempt (with a sieve from
http://code.activestate.com/recipes/117119/) only gave a speed decrease!!
But this had the sieve recreated for every triangle number. A global
sieve that is reused at each triangle number is better. But the speed
increase relative to the odd factors only is not dramatical.


# Based upon http://code.activestate.com/recipes/117119/

D = {9: 6} # contains composite numbers
Dlist = [2, 3] # list of already generated primes

def sieve():
    '''generator that yields all prime numbers'''
    global D
    global Dlist
    for p in Dlist:
        yield p
    q = Dlist[-1]+2
    while True:
        if q in D:
            p = D[q]
            x = q + p
            while x in D: x += p
            D[x] = p
        else:
            Dlist.append(q)
            yield q
            D[q*q] = 2*q
        q += 2

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    power = 0
    for factor in sieve():
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            # if you really want the factors then append((factor, power))
            powers.append(power+1)
        if num == 1:
            break
    return powers

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rhodri at wildebst.demon.co.uk  Mon Jul  6 11:22:43 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Mon, 06 Jul 2009 16:22:43 +0100
Subject: Python and webcam capture delay?
In-Reply-To: <czg4m.20786$vi5.9666@uutiset.elisa.fi>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
Message-ID: <op.uwnjn5ija8ncjz@gnudebst>

On Mon, 06 Jul 2009 07:10:38 +0100, jack catcher (nick) <nomail at thank.you>  
wrote:

> Tim Roberts kirjoitti:
>> "jack catcher (nick)" <nomail at thank.you> wrote:
>>> I'm thinking of using Python for capturing and showing live webcam  
>>> stream simultaneously between two computers via local area network.  
>>> Operating system is Windows. I'm going to begin with VideoCapture  
>>> extension, no ideas about other implementation yet. Do you have any  
>>> suggestions on how short delay I should hope to achieve in showing the  
>>> video? This would be part of a psychological experiment, so I would  
>>> need to deliver the video stream with a reasonable delay (say, below  
>>> 100ms).
>>  You need to do the math on this.  Remember that a full 640x480 RGB  
>> stream
>> at 30 frames per second runs 28 megabytes per second.  That's more than
>> twice what a 100 megabit network can pump.
>>  You can probably use Python to oversee this, but you might want to  
>> consider
>> using lower-level code to control the actual hardware.  If you are
>> targeting Windows, for example, you could write a DirectShow graph to  
>> pump
>> into a renderer that transmits out to a network, then another graph to
>> receive from the network and display it.
>>  You can manage the network latency by adding a delays in the local  
>> graph.
>
> Thanks Tim, you're correct about the math. What is your main point about  
> DirectShow: that it is generally faster and more reliable than doing the  
> job high-level, or that one could use coding/decoding in DirectShow to  
> speed up the transmission? I think the latter would be a great idea if  
> the latency were tolerable. On the other hand, I'd like to keep things  
> simple and do all the programming in Python. I've got no experience with  
> DirectShow, but I guess the filters need to be programmed in C++ and  
> called from Python?
>
> Another option might be to use resolution 320x240 at 15fps.

Does the webcam just deliver frames, or are you getting frames out of
a decoder layer?  If it's the latter, you want to distribute the encoded
video, which should be much lower bandwidth.  Exactly how you do that
depends a bit on what format the webcam claims to deliver.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From jeanmichel at sequans.com  Mon Jul  6 11:24:53 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 06 Jul 2009 17:24:53 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <000901c9fe42$b026cfc0$0d00a8c0@Hendrik>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<006201c9fd48$666d94e0$0d00a8c0@Hendrik>
	<4A51F3EB.1080509@sequans.com>
	<000901c9fe42$b026cfc0$0d00a8c0@Hendrik>
Message-ID: <4A521745.8040307@sequans.com>

Hendrik van Rooyen wrote:
> "Jean-Michel Pichavant" <jeanmichel at s....ns.com> wrote:
>
>   
>> Woot ! I'll keep this one in my mind, while I may not be that concerned 
>> by speed unlike the OP, I still find this way of doing very simple and 
>> so intuitive (one will successfully argue how I was not figuring this 
>> out by myself if it was so intuitive).
>> Anyway I wanted to participated to this thread, as soon as I saw 'due to 
>> python limitations' in the title, I foretold a hell of a thread ! This 
>> is just provocation ! :-)
>>     
>
> The OP was not being provocative - he has a real problem, 

I was just kidding, asserting for python limitations in this list 
guarantees that the thread will last for several days, whether or not 
the assertion is right.

JM


From python-url at phaseit.net  Mon Jul  6 11:33:47 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Mon, 6 Jul 2009 15:33:47 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul  6)
Message-ID: <h2t5gr$9mt$1@lairds.us>

QOTW:  "Simulating a shell with hooks on its I/O should be so complicated that
a 'script kiddie' has trouble writing a Trojan." - Scott David Daniels
    http://groups.google.com/group/comp.lang.python/msg/1c0f70d5fc69b5aa
    
    
    Python 3.1 final was released last week - congratulations!
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b37a041ce01d4168/
    
    Clarity of code vs. reusability in an introductory course:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b1a6ca84d3bfc483/
    
    A piece of code analyzed, looking for ways to improve speed:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/a420417a1e215cf0/
    
    Beginner question: How to define an indeterminate number of variables?
    How to create objects, and later reference them, when one doesn't know
    how many of them will be needed?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/c40e3c0c843ce6fb/
    
    Simple things made simple: correct use of Unicode helps a lot in this case:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/9cbb01aacf23fa8f/
    
    super() and multiple inheritance: __init__ is hard to get right. Also,
    Carl Banks explains how mixin classes are best used:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/c934715ac83dfbd/
    
    iter(function, sentinel) is a handy way to iterate in some cases, but
    beware of the fine print:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b977c3b39abd98b0
    
    The testing code should not merely repeat the code being tested (this
    fact isn't obvious to everyone):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8978c54b83f80bd6/
    
    Organize code so it can be run both in the source tree and after being
    installed:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/62284434d2ca5e1f/
    
    Mark Dickinson explains the C implementation of long integers:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/aa1d06d371658135/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From digitig at gmail.com  Mon Jul  6 11:43:43 2009
From: digitig at gmail.com (Tim Rowe)
Date: Mon, 6 Jul 2009 16:43:43 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2ogli$n9p$2@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
Message-ID: <aee48b3c0907060843y2635c531ydd27403a5c032c4e@mail.gmail.com>

2009/7/4 kj <no.email at please.post>:

> Precisely. ?As I've stated elsewhere, this is an internal helper
> function, to be called only a few times under very well-specified
> conditions. ?The assert statements checks that these conditions
> are as intended. ?I.e. they are checks against the module writer's
> programming errors.

Good for you. I'm convinced that you have used the assertion
appropriately, and the fact that so many here are unable to see that
looks to me like a good case for teaching the right use of assertions.
For what it's worth, I read assertions at the beginning of a procedure
as part of the specification of the procedure, and I use them there in
order to document the procedure. An assertion in that position is for
me a statement to the user of the procedure "it's your responsibility
to make sure that you never call this procedure in such a way as to
violate these conditions". They're part of a contract, as somebody
(maybe you) pointed out.

As somebody who works in the safety-critical domain, it's refreshing
to see somebody teaching students to think about the circumstances in
which a procedure can legitimately be called. The hostility you've
received to that idea is saddening, and indicative of why there's so
much buggy software out there.
-- 
Tim Rowe


From dmhouse at gmail.com  Mon Jul  6 11:46:45 2009
From: dmhouse at gmail.com (David House)
Date: Mon, 6 Jul 2009 16:46:45 +0100
Subject: try -> except -> else -> except?
Message-ID: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>

Hi all,

I'm looking for some structure advice. I'm writing something that
currently looks like the following:

try:
    <short amount of code that may raise a KeyError>
except KeyError:
    <error handler>
else:
    <nontrivial amount of code>

This is working fine. However, I now want to add a call to a function
in the `else' part that may raise an exception, say a ValueError. So I
was hoping to do something like the following:

try:
    <short amount of code that may raise a KeyError>
except KeyError:
    <error handler>
else:
    <nontrivial amount of code>
except ValueError:
    <error handler>

However, this isn't allowed in Python.

An obvious way round this is to move the `else' clause into the `try', i.e.,

try:
    <short amount of code that may raise a KeyError>
    <nontrivial amount of code>
except KeyError:
    <error handler>
except ValueError:
    <error handler>

However, I am loath to do this, for two reasons:

(i) if I modify the <nontrivial amount of code> block at some point in
the future so that it may raise a KeyError, I have to somehow tell
this exception from the one that may be generated from the <short
amount of code that may raise a KeyError> line.
(ii) it moves the error handler for the <short amount of code that may
raise a KeyError> bit miles away from the line that might generate the
error, making it unclear which code the KeyError error handler is an
error handler for.

What would be the best way to structure this?

-- 
-David


From piet at cs.uu.nl  Mon Jul  6 11:51:02 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 06 Jul 2009 17:51:02 +0200
Subject: Why is my code faster with append() in a loop than with a large
	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
	<m2r5wtetb0.fsf@cs.uu.nl>
Message-ID: <m2my7hero9.fsf@cs.uu.nl>

Sorry, there was an error in the sieve in my last example. Here is a
corrected version:

D = {9: 6} # contains composite numbers
Dlist = [2, 3] # list of already generated primes
def sieve():
    '''generator that yields all prime numbers'''
    global D
    global Dlist
    for q in Dlist:
        yield q
    while True:
        q += 2
        p = D.pop(q, 0)
        if p:
            x = q + p
            while x in D: x += p
            D[x] = p
        else:
            Dlist.append(q)
            D[q*q] = 2*q
            yield q

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul  6 11:56:21 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 06 Jul 2009 17:56:21 +0200
Subject: try -> except -> else -> except?
References: <mailman.2701.1246895207.8015.python-list@python.org>
Message-ID: <m2iqi5erfe.fsf@cs.uu.nl>

>>>>> David House <dmhouse at gmail.com> (DH) wrote:

>DH> Hi all,
>DH> I'm looking for some structure advice. I'm writing something that
>DH> currently looks like the following:

>DH> try:
>DH>     <short amount of code that may raise a KeyError>
>DH> except KeyError:
>DH>     <error handler>
>DH> else:
>DH>     <nontrivial amount of code>

>DH> This is working fine. However, I now want to add a call to a function
>DH> in the `else' part that may raise an exception, say a ValueError. So I
>DH> was hoping to do something like the following:

>DH> try:
>DH>     <short amount of code that may raise a KeyError>
>DH> except KeyError:
>DH>     <error handler>
>DH> else:
>DH>     <nontrivial amount of code>
>DH> except ValueError:
>DH>     <error handler>

>DH> However, this isn't allowed in Python.

>DH> An obvious way round this is to move the `else' clause into the `try', i.e.,

>DH> try:
>DH>     <short amount of code that may raise a KeyError>
>DH>     <nontrivial amount of code>
>DH> except KeyError:
>DH>     <error handler>
>DH> except ValueError:
>DH>     <error handler>

>DH> However, I am loath to do this, for two reasons:

>DH> (i) if I modify the <nontrivial amount of code> block at some point in
>DH> the future so that it may raise a KeyError, I have to somehow tell
>DH> this exception from the one that may be generated from the <short
>DH> amount of code that may raise a KeyError> line.
>DH> (ii) it moves the error handler for the <short amount of code that may
>DH> raise a KeyError> bit miles away from the line that might generate the
>DH> error, making it unclear which code the KeyError error handler is an
>DH> error handler for.

>DH> What would be the best way to structure this?

try:
    <short amount of code that may raise a KeyError>
except KeyError:
    <error handler>
else:
    try:
        <nontrivial amount of code>
    except ValueError:
        <error handler>

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at rgbaz.eu  Mon Jul  6 12:02:18 2009
From: python at rgbaz.eu (Python)
Date: Mon, 6 Jul 2009 18:02:18 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
Message-ID: <DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>


On 6 jul 2009, at 17:46, David House wrote:

> Hi all,
>
> I'm looking for some structure advice. I'm writing something that
> currently looks like the following:
>
> try:
>    <short amount of code that may raise a KeyError>
> except KeyError:
>    <error handler>
> else:
>    <nontrivial amount of code>
>
> This is working fine. However, I now want to add a call to a function
> in the `else' part that may raise an exception, say a ValueError. So I
> was hoping to do something like the following:
>
> try:
>    <short amount of code that may raise a KeyError>
> except KeyError:
>    <error handler>
> else:
>    <nontrivial amount of code>
> except ValueError:
>    <error handler>
>
> However, this isn't allowed in Python.
>
> An obvious way round this is to move the `else' clause into the  
> `try', i.e.,
>
> try:
>    <short amount of code that may raise a KeyError>
>    <nontrivial amount of code>
> except KeyError:
>    <error handler>
> except ValueError:
>    <error handler>
>
> However, I am loath to do this, for two reasons:
>
> (i) if I modify the <nontrivial amount of code> block at some point in
> the future so that it may raise a KeyError, I have to somehow tell
> this exception from the one that may be generated from the <short
> amount of code that may raise a KeyError> line.
> (ii) it moves the error handler for the <short amount of code that may
> raise a KeyError> bit miles away from the line that might generate the
> error, making it unclear which code the KeyError error handler is an
> error handler for.
>
> What would be the best way to structure this?
>
> -- 
> -David
>

as far as I know try has no 'else'
it's 'finally'

try:
	a
except:
	b
except:
	c
finally:
	d

gr
Arno



From deets at nospam.web.de  Mon Jul  6 12:10:36 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 06 Jul 2009 18:10:36 +0200
Subject: How to map size_t using ctypes?
References: <mailman.2691.1246888326.8015.python-list@python.org>
Message-ID: <7belo1F21fs3vU1@mid.uni-berlin.de>

Philip Semanchuk wrote:

> Hi all,
> I can't figure out how to map a C variable of size_t via Python's
> ctypes module. Let's say I have a C function like this:
> 
> void populate_big_array(double *the_array, size_t element_count) {...}
> 
> How would I pass parameter 2? A long (or ulong) will (probably) work
> (on most platforms), but I like my code to be more robust than that.
> Furthermore, this is scientific code and it's entirely possible that
> someone will want to pass a huge array with more elements than can be
> described by a 32-bit long.

from ctypes import c_size_t

doesn't work for you? On my system, it's aliased to c_ulong, but I guess
that's depending on the platfrom of course.

Diez


From dmhouse at gmail.com  Mon Jul  6 12:14:23 2009
From: dmhouse at gmail.com (David House)
Date: Mon, 6 Jul 2009 17:14:23 +0100
Subject: try -> except -> else -> except?
In-Reply-To: <DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
	<DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>
Message-ID: <ebe43d680907060914o6e4d859qd90a768f4f52bc88@mail.gmail.com>

2009/7/6 Python <python at rgbaz.eu>:
> as far as I know try has no 'else'

It does:
http://docs.python.org/reference/compound_stmts.html#the-try-statement

> it's 'finally'

There is a `finally', too, but they are semantically different. See
the above link.

-- 
-David


From python at rgbaz.eu  Mon Jul  6 12:17:24 2009
From: python at rgbaz.eu (Python)
Date: Mon, 6 Jul 2009 18:17:24 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <ebe43d680907060914o6e4d859qd90a768f4f52bc88@mail.gmail.com>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
	<DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>
	<ebe43d680907060914o6e4d859qd90a768f4f52bc88@mail.gmail.com>
Message-ID: <1661ED1F-8AC9-48A7-8C87-0090942664B1@rgbaz.eu>


On 6 jul 2009, at 18:14, David House wrote:

> 2009/7/6 Python <python at rgbaz.eu>:
>> as far as I know try has no 'else'
>
> It does:
> http://docs.python.org/reference/compound_stmts.html#the-try-statement
>
>> it's 'finally'
>
> There is a `finally', too, but they are semantically different. See
> the above link.
>
> -- 
> -David
>
>
ah yeah you;re right, sry

shouldn't the else statement come after the except ones maybe?


From usernet at ilthio.net  Mon Jul  6 12:25:33 2009
From: usernet at ilthio.net (Tim Harig)
Date: Mon, 06 Jul 2009 16:25:33 GMT
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
	<d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
Message-ID: <1Ap4m.2113$8r.633@nlpi064.nbdc.sbc.com>

On 2009-07-06, RAM <serverin2000 at yahoo.com> wrote:
> I am trying to do this on windows. My program(executable) has been
> written in VC++ and when I run this program, I need to click on one
> button on the program GUI i,e just I am entering "Enter key" on the
> key board. But this needs manual process. So i need to write a python
> script which invokes my program and pass "Enter key" event to my
> program so that it runs without manual intervention.

This can be done using the WScript.WshShell.SendKeys() method when running
Python with Windows Scripting Host by using the .pyw extension:

http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx


From philip at semanchuk.com  Mon Jul  6 12:29:21 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 12:29:21 -0400
Subject: How to map size_t using ctypes?
In-Reply-To: <7belo1F21fs3vU1@mid.uni-berlin.de>
References: <mailman.2691.1246888326.8015.python-list@python.org>
	<7belo1F21fs3vU1@mid.uni-berlin.de>
Message-ID: <DB4ED723-C8DD-492F-A7CC-B3CE14F8B723@semanchuk.com>


On Jul 6, 2009, at 12:10 PM, Diez B. Roggisch wrote:

> Philip Semanchuk wrote:
>
>> Hi all,
>> I can't figure out how to map a C variable of size_t via Python's
>> ctypes module. Let's say I have a C function like this:
>>
>> void populate_big_array(double *the_array, size_t element_count)  
>> {...}
>>
>> How would I pass parameter 2? A long (or ulong) will (probably) work
>> (on most platforms), but I like my code to be more robust than that.
>> Furthermore, this is scientific code and it's entirely possible that
>> someone will want to pass a huge array with more elements than can be
>> described by a 32-bit long.
>
> from ctypes import c_size_t
>
> doesn't work for you? On my system, it's aliased to c_ulong, but I  
> guess
> that's depending on the platfrom of course.

D'oh! [slaps forehead]

That will teach me to RTFM. In my 2.5 doc, it's not listed in the  
"Fundamental data types" section in the tutorial, but it is mentioned  
in "Fundamental data types" in the ctypes reference. You'd be  
surprised at the amount of Googling I did without learning this on my  
own.

Thanks
Philip


From "sandrodll[remove]" at googlemail.com  Mon Jul  6 12:32:47 2009
From: "sandrodll[remove]" at googlemail.com (gialloporpora)
Date: Mon, 06 Jul 2009 18:32:47 +0200
Subject: Help to find a regular expression to parse po file
In-Reply-To: <hbf.20090706bevs@bombur.uio.no>
References: <4A52084D.1010900@googlemail.com> <hbf.20090706bevs@bombur.uio.no>
Message-ID: <4A52272F.10209@googlemail.com>

Risposta al messaggio di Hallvard B Furuseth :


>
> I don't know the syntax of a po file, but this works for the
> snippet you posted:
>
> arg_re = r'"[^\\\"]*(?:\\.[^\\\"]*)*"'
> arg_re = '%s(?:\s+%s)*' % (arg_re, arg_re)
> find_re = re.compile(
>      r'^msgid\s+(' + arg_re + ')\s*\nmsgstr\s+(' + arg_re + ')\s*\n', re.M)
>
> However, can \ quote a newline? If so, replace \\. with \\[\s\S] or
> something.
> Can there be other keywords between msgid and msgstr?  If so,
> add something like (?:\w+\s+<arg_re>\s*\n)*? between them.
> Can msgstr come before msgid? If so, forget using a single regexp.
> Anything else to the syntax to look out for?  Single quotes, maybe?
>
> Is it a problem if the regexp isn't quite right and doesn't match all
> cases, yet doesn't report an error when that happens?
>
> All in all, it may be a bad idea to sqeeze this into a single regexp.
> It gets ugly real fast.  Might be better to parse the file in a more
> regular way, maybe using regexps just to extract each (keyword, "value")
> pair.
>
Thank you very much, Haldvard, it seem to works, there is a strange 
match in the file header but I could skip the first match.


The po files have this structure:
http://bit.ly/18qbVc

msgid "string to translate"
"   second string to match"
"   n string to match"
msgstr "translated sting"
"   second translated string"
"  n translated string"
One or more new line before the next group.

In past I have created a Python script to parse PO files  where msgid 
and msgstr are in two sequential lines, for example:

msgid "string to translate"
msgstr "translated string"

now the problem is how to match also (optional) string between msgid and 
msgstr.

Sandro







From davea at ieee.org  Mon Jul  6 12:49:49 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 12:49:49 -0400
Subject: Why is my code faster with append() in a loop than with a
	large	list?
In-Reply-To: <4A52089F.7020301@mrabarnett.plus.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<4A51CD6A.2010106@dejaviewphoto.com>
	<4A52089F.7020301@mrabarnett.plus.com>
Message-ID: <4A522B2D.60407@ieee.org>

MRAB wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
> [snip]
>> It would probably save some time to not bother storing the zeroes in 
>> the list at all.  And it should help if you were to step through a 
>> list of primes, rather than trying every possible int.  Or at least 
>> constrain yourself to odd numbers (after the initial case of 2).
>>
> Or stop looking for more factors when you've passed the square root of
> num. I don't know what effect there'll be on the time if you recalculate
> the square root when num changes (expensive calculation vs smaller
> search space).
>
> </div>
>
But if I remember the code, it stopped when the quotient is one, which 
is usually sooner than the square root.  And no need to precalculate the 
square root.



From Scott.Daniels at Acm.Org  Mon Jul  6 12:53:34 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 09:53:34 -0700
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <m2r5wtetb0.fsf@cs.uu.nl>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
	<m2r5wtetb0.fsf@cs.uu.nl>
Message-ID: <U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>

Piet van Oostrum wrote:
>>>>>> Dave Angel <davea at dejaviewphoto.com> (DA) wrote:
> 
>> DA> It would probably save some time to not bother storing the zeroes in the
>> DA> list at all.  And it should help if you were to step through a list of
>> DA> primes, rather than trying every possible int.  Or at least constrain
>> DA> yourself to odd numbers (after the initial case of 2).
> 
> ...
> # Based upon http://code.activestate.com/recipes/117119/
> 
> D = {9: 6} # contains composite numbers
XXX Dlist = [2, 3] # list of already generated primes
   Elist = [(2, 4), (3, 9)] # list of primes and their squares
> 
XXX def sieve():
XXX   '''generator that yields all prime numbers'''
XXX   global D
XXX   global Dlist
  def sieve2():
      '''generator that yields all primes and their squares'''
      # No need for global declarations, we alter, not replace
XXX   for p in Dlist:
XXX       yield p
XXX   q = Dlist[-1]+2

       for pair in Elist:
           yield pair
       q = pair[0] + 2

>     while True:
>         if q in D:
>             p = D[q]
>             x = q + p
>             while x in D: x += p
>             D[x] = p
>         else:
XXX           Dlist.append(q)
XXX           yield q
XXX           D[q*q] = 2*q
               square = q * q
               pair = q, square
               Elist.append(pair)
               yield pair
               D[square] = 2 * q
>         q += 2
> 
> def factorise(num):
>     """Returns a list of prime factor powers. For example:
>         factorise(6) will return
>         [2, 2] (the powers are returned one higher than the actual value)
>         as in, 2^1 * 3^1 = 6."""
>     powers = []
>     power = 0
XXX   for factor in sieve():
       for factor, limit in sieve2():
>         power = 0
>         while num % factor == 0:
>             power += 1
>             num /= factor
XXX       if power > 0:
           if power: # good enough here, and faster
>             # if you really want the factors then append((factor, power))
>             powers.append(power+1)
XXX       if num == 1:
XXX           break
XXX   return powers
           if num < limit:
               if num > 1:
                   # if you really want the factors then append((num, 1))
                   powers.append(2)
               return powers

OK, that's a straightforward speedup, _but_:
      factorize(6) == [2, 2] == factorize(10) ==  factorize(15)
So I am not sure exactly what you are calculating.


--Scott David Daniels
Scott.Daniels at Acm.Org


From davea at ieee.org  Mon Jul  6 12:54:35 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 12:54:35 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwninxtza8ncjz@gnudebst>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<op.uwninxtza8ncjz@gnudebst>
Message-ID: <4A522C4B.20102@ieee.org>

Rhodri James wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">On Mon, 
> 06 Jul 2009 10:58:21 +0100, Steven D'Aprano 
> <steve at remove-this-cybersource.com.au> wrote:
>
>> On Mon, 06 Jul 2009 02:19:51 -0300, Gabriel Genellina wrote:
>>
>>> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
>>> <steve at remove-this-cybersource.com.au> escribi?:
>>>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>>>
>>>>> I wonder how many people have been tripped up by the fact that
>>>>>
>>>>>     ++n
>>>>>
>>>>> and
>>>>>
>>>>>     --n
>>>>>
>>>>> fail silently for numeric-valued n.
>>>>
>>>> What do you mean, "fail silently"? They do exactly what you should
>>>> expect:
>>>>>>> ++5  # positive of a positive number is positive
>>>>
>>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>>> that are buggy, not Python.
>>>
>>> Well, those expectations are taken seriously when new features are
>>> introduced into the language - and sometimes the feature is dismissed
>>> just because it would be confusing for some. If a += 1 works, expecting
>>> ++a to have the same meaning is very reasonable (for those coming from
>>> languages with a ++ operator, like C or Java) - more when ++a is a
>>> perfectly valid expression. If this issue isn't listed under the 
>>> various
>>> "Python gotchas" articles, it should...
>>
>> The fact that it isn't suggests strongly to me that it isn't that common
>> a surprise even for Java and C programmers. This is the first time I've
>> seen anyone raise it as an issue.
>
> Indeed, arguably it's a bug for C compilers to fail to find the valid
> parsing of "++5" as "+(+5)".  All I can say is that I've never even
> accidentally typed that in twenty years of C programming.
>
But the C language specifically defines the tokenizer as doing a 
max-match, finding the longest legal token at any point.  That's how 
many things that would otherwise be ambiguous are well-defined.  For 
example, if you want to divide two integers, given pointers to them, you 
need a space between the slash and the start.
         *p1/*p2    begins a comment,  while   *p1/ *p2   does a division




From davea at ieee.org  Mon Jul  6 13:13:48 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 13:13:48 -0400
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<mailman.2683.1246875006.8015.python-list@python.org>	<m2r5wtetb0.fsf@cs.uu.nl>
	<U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>
Message-ID: <4A5230CC.2020801@ieee.org>

Scott David Daniels wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Piet van 
> Oostrum wrote:
>>>>>>> Dave Angel <davea at dejaviewphoto.com> (DA) wrote:
>>
>>> DA> It would probably save some time to not bother storing the 
>>> zeroes in the
>>> DA> list at all.  And it should help if you were to step through a 
>>> list of
>>> DA> primes, rather than trying every possible int.  Or at least 
>>> constrain
>>> DA> yourself to odd numbers (after the initial case of 2).
>>
>> ...
>> # Based upon http://code.activestate.com/recipes/117119/
>>
>> D = {9: 6} # contains composite numbers
> XXX Dlist = [2, 3] # list of already generated primes
>   Elist = [(2, 4), (3, 9)] # list of primes and their squares
>>
> XXX def sieve():
> XXX   '''generator that yields all prime numbers'''
> XXX   global D
> XXX   global Dlist
>  def sieve2():
>      '''generator that yields all primes and their squares'''
>      # No need for global declarations, we alter, not replace
> XXX   for p in Dlist:
> XXX       yield p
> XXX   q = Dlist[-1]+2
>
>       for pair in Elist:
>           yield pair
>       q = pair[0] + 2
>
>>     while True:
>>         if q in D:
>>             p = D[q]
>>             x = q + p
>>             while x in D: x += p
>>             D[x] = p
>>         else:
> XXX           Dlist.append(q)
> XXX           yield q
> XXX           D[q*q] = 2*q
>               square = q * q
>               pair = q, square
>               Elist.append(pair)
>               yield pair
>               D[square] = 2 * q
>>         q += 2
>>
>> def factorise(num):
>>     """Returns a list of prime factor powers. For example:
>>         factorise(6) will return
>>         [2, 2] (the powers are returned one higher than the actual 
>> value)
>>         as in, 2^1 * 3^1 = 6."""
>>     powers = []
>>     power = 0
> XXX   for factor in sieve():
>       for factor, limit in sieve2():
>>         power = 0
>>         while num % factor == 0:
>>             power += 1
>>             num /= factor
> XXX       if power > 0:
>           if power: # good enough here, and faster
>>             # if you really want the factors then append((factor, 
>> power))
>>             powers.append(power+1)
> XXX       if num == 1:
> XXX           break
> XXX   return powers
>           if num < limit:
>               if num > 1:
>                   # if you really want the factors then append((num, 1))
>                   powers.append(2)
>               return powers
>
> OK, that's a straightforward speedup, _but_:
>      factorize(6) == [2, 2] == factorize(10) ==  factorize(15)
> So I am not sure exactly what you are calculating.
>
>
> --Scott David Daniels
> Scott.Daniels at Acm.Org
>
> </div>
>
The OP only needed the number of factors, not the actual factors.  So 
the zeroes in the list are unneeded.  6, 10, and 15 each have 4 factors.




From sajmikins at gmail.com  Mon Jul  6 13:15:22 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Mon, 6 Jul 2009 13:15:22 -0400
Subject: Tree structure consuming lot of memory
In-Reply-To: <ff4d16090907060312n6df077capcce97ddd0786983@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>
	<ff4d16090907060312n6df077capcce97ddd0786983@mail.gmail.com>
Message-ID: <50f98a4c0907061015n68191f9bj868b8e1b8908223c@mail.gmail.com>

On Mon, Jul 6, 2009 at 6:12 AM, mayank gupta<mooniitk at gmail.com> wrote:
> Thanks for the other possibilites. I would consider option (2) and (3) to
> improve my code.
>
> But out of curiosity, I would still like to know why does an object of a
> Python-class consume "so" much of memory (1.4 kb), and this memory usage has
> nothing to do with its attributes.
>
> Thanks
>
> Regards.
>
> On Mon, Jul 6, 2009 at 12:03 PM, Chris Rebert <clp2 at rebertia.com> wrote:
>>
>> On Mon, Jul 6, 2009 at 2:55 AM, mayank gupta<mooniitk at gmail.com> wrote:
>> > Hi,
>> >
>> > I am creating a tree data-structure in python; with nodes of the tree
>> > created by a simple class :
>> >
>> > class Node :
>> > ?????? def __init__(self , .... other attributes):
>> > ????????????? # initialise the attributes here!!
>> >
>> > But the problem is I am working with a huge tree (millions of nodes);
>> > and
>> > each node is consuming much more memory than it should. After a little
>> > analysis, I found out that in general it uses about 1.4 kb of memory for
>> > each node!!
>> > I will be grateful if someone could help me optimize the memory usage.
>>
>> (1) Use __slots__ (see
>> http://docs.python.org/reference/datamodel.html#slots)
>> (2) Use some data structure other than a tree
>> (3) Rewrite your Node/Tree implementation in C
>>
>> Cheers,
>> Chris
>> --
>> http://blog.rebertia.com
>

For option 2 you should try using the built in types, list tuple or
dict.  You might get better results.

I'm curious too as to why the class/instance code should take so much
memory, could you mention more about the code?


From python at mrabarnett.plus.com  Mon Jul  6 13:20:59 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 18:20:59 +0100
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <4A522B2D.60407@ieee.org>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<4A51CD6A.2010106@dejaviewphoto.com>
	<4A52089F.7020301@mrabarnett.plus.com> <4A522B2D.60407@ieee.org>
Message-ID: <4A52327B.3000403@mrabarnett.plus.com>

Dave Angel wrote:
> MRAB wrote:
>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
>> Angel wrote:
>> [snip]
>>> It would probably save some time to not bother storing the zeroes in 
>>> the list at all.  And it should help if you were to step through a 
>>> list of primes, rather than trying every possible int.  Or at least 
>>> constrain yourself to odd numbers (after the initial case of 2).
>>>
>> Or stop looking for more factors when you've passed the square root of
>> num. I don't know what effect there'll be on the time if you recalculate
>> the square root when num changes (expensive calculation vs smaller
>> search space).
>>
>> </div>
>>
> But if I remember the code, it stopped when the quotient is one, which 
> is usually sooner than the square root.  And no need to precalculate the 
> square root.
> 
If the number is a large prime then the code will try all the numbers up
to that, eg if num == 1000003 then it'll try 2..1000003 even though it
could've given up after 1000.


From pescadero10 at gmail.com  Mon Jul  6 13:30:41 2009
From: pescadero10 at gmail.com (pescadero10)
Date: Mon, 6 Jul 2009 10:30:41 -0700 (PDT)
Subject: updating, adding new pages to confluence remotely, using python
Message-ID: <c5ce5132-f4bd-46dc-938c-d4d6fd4dc5b6@x6g2000prc.googlegroups.com>

Hello,

I am new to python and have been trying to figure out how to remotely
add new pages to my confluence
wiki space. I'm running my python script from a linux rhel4 machine
and using confluence version 2.10. As a test I tried to read from
stdin and write a page but it fails- that is, the script runs without
errors but nothing is added.  Does anyone have an example of how this
is done?  Here is my script:

--- begin script -----------
#!/usr/local/bin/python
#
# Reads from standard input, dumps it onto a Confluence page
# You'll need to modify the URL/username/password/spacekey/page title
# below, because I'm too lazy to bother with argv.

import sys
from xmlrpclib import Server

# Read the text of the page from standard input
content = sys.stdin.read()

s = Server("http://confluence.slac.stanford.edu/display/GO/Home")
token = s.confluence1.login("chee", "******")
page = s.confluence1.getPage(token, "SPACEKEY", "TEST Python-2-
Confluence")
page["content"] = content
s.confluence1.storePage(token, page)

newpagedata = {"title":"New Page","content":"new
content","space":"spaceKey"}
newpage = s.confluence1.storePage(token, newpagedata);
------------ end script ------------------------

Any help would be greatly appreciated.

thanks, Pescadero10


From nomail at thank.you  Mon Jul  6 13:41:03 2009
From: nomail at thank.you (jack catcher (nick))
Date: Mon, 06 Jul 2009 20:41:03 +0300
Subject: Python and webcam capture delay?
In-Reply-To: <mailman.2698.1246893772.8015.python-list@python.org>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
Message-ID: <RGq4m.20945$vi5.15615@uutiset.elisa.fi>

Rhodri James kirjoitti:
> On Mon, 06 Jul 2009 07:10:38 +0100, jack catcher (nick) 
> <nomail at thank.you> wrote:
> 
>> Tim Roberts kirjoitti:
>>> "jack catcher (nick)" <nomail at thank.you> wrote:
>>>> I'm thinking of using Python for capturing and showing live webcam 
>>>> stream simultaneously between two computers via local area network. 
>>>> Operating system is Windows. I'm going to begin with VideoCapture 
>>>> extension, no ideas about other implementation yet. Do you have any 
>>>> suggestions on how short delay I should hope to achieve in showing 
>>>> the video? This would be part of a psychological experiment, so I 
>>>> would need to deliver the video stream with a reasonable delay (say, 
>>>> below 100ms).
>>>  You need to do the math on this.  Remember that a full 640x480 RGB 
>>> stream
>>> at 30 frames per second runs 28 megabytes per second.  That's more than
>>> twice what a 100 megabit network can pump.
>>>  You can probably use Python to oversee this, but you might want to 
>>> consider
>>> using lower-level code to control the actual hardware.  If you are
>>> targeting Windows, for example, you could write a DirectShow graph to 
>>> pump
>>> into a renderer that transmits out to a network, then another graph to
>>> receive from the network and display it.
>>>  You can manage the network latency by adding a delays in the local 
>>> graph.
>>
>> Thanks Tim, you're correct about the math. What is your main point 
>> about DirectShow: that it is generally faster and more reliable than 
>> doing the job high-level, or that one could use coding/decoding in 
>> DirectShow to speed up the transmission? I think the latter would be a 
>> great idea if the latency were tolerable. On the other hand, I'd like 
>> to keep things simple and do all the programming in Python. I've got 
>> no experience with DirectShow, but I guess the filters need to be 
>> programmed in C++ and called from Python?
>>
>> Another option might be to use resolution 320x240 at 15fps.
> 
> Does the webcam just deliver frames, or are you getting frames out of
> a decoder layer?  If it's the latter, you want to distribute the encoded
> video, which should be much lower bandwidth.  Exactly how you do that
> depends a bit on what format the webcam claims to deliver.

Well, getting already encoded video from the webcam sounds almost like a 
free lunch (which it probably is not). At least I wouldn't want to get 
too long a delay because of the encoding.

I haven't got the webcam(s) yet, and I guess I can basically purchase 
any ones I find suitable for getting the job done. Any recommendations?


From "sandrodll[remove]" at googlemail.com  Mon Jul  6 13:42:46 2009
From: "sandrodll[remove]" at googlemail.com (gialloporpora)
Date: Mon, 06 Jul 2009 19:42:46 +0200
Subject: Help to find a regular expression to parse po file
In-Reply-To: <mailman.2697.1246893138.8015.python-list@python.org>
References: <4A52084D.1010900@googlemail.com>
	<mailman.2697.1246893138.8015.python-list@python.org>
Message-ID: <4A523796.3050509@googlemail.com>

Risposta al messaggio di MRAB :

> gialloporpora wrote:
>> Hi all,
>> I would like to extract string from a PO file. To do this I have created
>> a little python function to parse po file and extract string:
>>
>> import re
>> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
>> m=r.findall(s)
>>
>> where s is a po file like this:
>>
>> msgctxt "write ubiquity commands.description"
>> msgid "Takes you to the Ubiquity<a
>> href=\"chrome://ubiquity/content/editor.html\">command editor</a>  page."
>> msgstr "Apre l'<a href=\"chrome://ubiquity/content/editor.html\">editor
>> dei comandi</a>  di Ubiquity."
>>
>>
>> #. list ubiquity commands command:
>> #. use | to separate multiple name values:
>> msgctxt "list ubiquity commands.names"
>> msgid "list ubiquity commands"
>> msgstr "elenco comandi disponibili"
>>
>> msgctxt "list ubiquity commands.description"
>> msgid "Opens<a href=\"chrome://ubiquity/content/cmdlist.html\">the
>> list</a>\n"
>> "      of all Ubiquity commands available and what they all do."
>> msgstr "Apre una<a
>> href=\"chrome://ubiquity/content/cmdlist.html\">pagina</a>\n"
>> "      in cui sono elencati tutti i comandi disponibili e per ognuno
>> viene spiegato in breve a cosa serve."
>>
>>
>>
>> #. change ubiquity settings command:
>> #. use | to separate multiple name values:
>> msgctxt "change ubiquity settings.names"
>> msgid "change ubiquity settings|change ubiquity preferences|change
>> ubiquity skin"
>> msgstr "modifica impostazioni di ubiquity|modifica preferenze di
>> ubiquity|modifica tema di ubiquity"
>>
>> msgctxt "change ubiquity settings.description"
>> msgid "Takes you to the<a
>> href=\"chrome://ubiquity/content/settings.html\">settings</a>  page,\n"
>> "      where you can change your skin, key combinations, etc."
>> msgstr "Apre la pagina<a
>> href=\"chrome://ubiquity/content/settings.html\">delle impostazioni</a>
>> di Ubiquity,\n"
>> "     dalla quale ?? possibile modificare la combinazione da tastiera
>> utilizzata per richiamare Ubiquity, il tema, ecc."
>>
>>
>>
>> but, obviusly,  with the code above the  last string is not matched. If
>> I use re.DOTALL to match also new line character it not works because it
>> match the entire file, I would like to stop the matching when "msgstr"
>> is found.
>>
>> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n\\n",re.DOTALL)
>>
>> is it possible or not ?
>>
> You could try:
>
> regex = re.compile(r"msgid (.*(?:\n".*")*)\nmsgstr (.*(?:\n".*")*)$")
>
> and then, if necessary, tidy what you get.


MRAB, thank you for your help, I have tried the code posted by Hallvard 
because I have seen it before and it works. Now I'll check also your 
suggestions.
Sandro

-- 
*Pink Floyd ? The Great Gig in the Sky* - http://sn.im/kggo7
* FAQ* di /it-alt.comp.software.mozilla/: http://bit.ly/1MZ04d


From bdesth.quelquechose at free.quelquepart.fr  Mon Jul  6 13:48:29 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Mon, 06 Jul 2009 19:48:29 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <mailman.2701.1246895207.8015.python-list@python.org>
References: <mailman.2701.1246895207.8015.python-list@python.org>
Message-ID: <4a52548c$0$31414$426a74cc@news.free.fr>

David House a ?crit :
> Hi all,
> 
> I'm looking for some structure advice. I'm writing something that
> currently looks like the following:
> 
> try:
>     <short amount of code that may raise a KeyError>
> except KeyError:
>     <error handler>
> else:
>     <nontrivial amount of code>
> 
> This is working fine. However, I now want to add a call to a function
> in the `else' part that may raise an exception, say a ValueError.

If your error handler terminates the function (which is usually the case 
when using the else clause), you can just skip the else statement, ie:

try:
     <short amount of code that may raise a KeyError>
except KeyError:
     <error handler with early exit>
<nontrivial amount of code>

Then adding one or more try/except is just trivial.


> So I
> was hoping to do something like the following:
> 
> try:
>     <short amount of code that may raise a KeyError>
> except KeyError:
>     <error handler>
> else:
>     <nontrivial amount of code>
> except ValueError:
>     <error handler>
> 
> However, this isn't allowed in Python.

Nope. But this is legal:


try:
     <short amount of code that may raise a KeyError>
except KeyError:
     <error handler>
else:
     try:
         <nontrivial amount of code>
     except ValueError:
         <error handler>



> An obvious way round this is to move the `else' clause into the `try'

"obvious" but not necessarily the best thing to do.

(snip - cf above for simple answers)




From bdesth.quelquechose at free.quelquepart.fr  Mon Jul  6 13:49:49 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Mon, 06 Jul 2009 19:49:49 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <mailman.2707.1246899334.8015.python-list@python.org>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
	<mailman.2707.1246899334.8015.python-list@python.org>
Message-ID: <4a5254db$0$31414$426a74cc@news.free.fr>

Python a ?crit :
(snip whole OP)


> as far as I know try has no 'else'

Then you may want to RTFM.



From ethan at stoneleaf.us  Mon Jul  6 13:53:31 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Mon, 06 Jul 2009 10:53:31 -0700
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A523A1B.70901@stoneleaf.us>

Many thanks to all who replied!  And, yes, I will *definitely* use raw 
strings from now on.  :)

~Ethan~


From bdesth.quelquechose at free.quelquepart.fr  Mon Jul  6 13:56:00 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Mon, 06 Jul 2009 19:56:00 +0200
Subject: How Python Implements "long integer"?
In-Reply-To: <249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
	<68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com>
	<249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>
Message-ID: <4a52564e$0$31414$426a74cc@news.free.fr>

Mark Dickinson a ?crit :
> On Jul 5, 1:09 pm, Pedram <pm567... at gmail.com> wrote:
>> Thanks for reply,
>> Sorry I can't explain too clear! I'm not English ;)
> 
> That's shocking.  Everyone should be English. :-)
> 
Mark, tu sors !


From davea at ieee.org  Mon Jul  6 14:28:05 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 14:28:05 -0400
Subject: Why is my code faster with append() in a loop than with a
	large	list?
In-Reply-To: <4A52327B.3000403@mrabarnett.plus.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<4A51CD6A.2010106@dejaviewphoto.com>	<4A52089F.7020301@mrabarnett.plus.com>
	<4A522B2D.60407@ieee.org> <4A52327B.3000403@mrabarnett.plus.com>
Message-ID: <4A524235.1010002@ieee.org>

MRAB wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
>> MRAB wrote:
>>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
>>> Angel wrote:
>>> [snip]
>>>> It would probably save some time to not bother storing the zeroes 
>>>> in the list at all.  And it should help if you were to step through 
>>>> a list of primes, rather than trying every possible int.  Or at 
>>>> least constrain yourself to odd numbers (after the initial case of 2).
>>>>
>>> Or stop looking for more factors when you've passed the square root of
>>> num. I don't know what effect there'll be on the time if you 
>>> recalculate
>>> the square root when num changes (expensive calculation vs smaller
>>> search space).
>>>
>>> </div>
>>>
>> But if I remember the code, it stopped when the quotient is one, 
>> which is usually sooner than the square root.  And no need to 
>> precalculate the square root.
>>
> If the number is a large prime then the code will try all the numbers up
> to that, eg if num == 1000003 then it'll try 2..1000003 even though it
> could've given up after 1000.
>
> </div>
>
That's one reason I suggested (and Piet implemented) a sieve.  You can 
stop dividing when the square of the next prime exceeds your quotient.



From tn.pablo at gmail.com  Mon Jul  6 14:49:56 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Mon, 6 Jul 2009 13:49:56 -0500
Subject: A Bug By Any Other Name ...
In-Reply-To: <00df01c9fe33$10c36d80$0d00a8c0@Hendrik>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com> 
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<h2sgiq$6ud$1@ger.gmane.org> 
	<00df01c9fe33$10c36d80$0d00a8c0@Hendrik>
Message-ID: <fdd00b510907061149v5145afa4kd002dce221181fba@mail.gmail.com>

On Mon, Jul 6, 2009 at 07:12, Hendrik van Rooyen<mail at microcorp.co.za> wrote:
> "Terry Reedy" <t...j at ..el.edu> wrote:
>
>> Gabriel Genellina wrote:
>> >
>> > In this case, a note in the documentation warning about the potential
>> > confusion would be fine.
>>
>> How would that help someone who does not read the doc?
>
> It obviously won't.
>
> All it will do, is that it will enable people on this group,
> who may read the manual, to tell people who complain,
> to RTFM.

Yes, it's their problem if they don't read the docs.

>
> ?I agree that it would be a good idea to make it an
> error, or a warning - "this might not do what you
> think it does", or an "are you sure?" exception.
>
> ?:-)
>
> - Hendrik

That would be even harder than adding a line to the docs.  Besides,
the problem that Mr. alex23 pointed: "where do you stop?" would really
get out of hand.

-- 
Pablo Torres N.


From jdnier at gmail.com  Mon Jul  6 14:52:26 2009
From: jdnier at gmail.com (David Niergarth)
Date: Mon, 6 Jul 2009 11:52:26 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <ee914a9f-c654-46b7-86f7-812024c1ea90@g19g2000yql.googlegroups.com>

I remember in college taking an intro programming class (C++) where
the professor started us off writing a program to factor polynomials;
he probably also incorporated binary search into an assignment. But
people don't generally use Python to implement binary search or factor
polynomials so maybe you should start with a problem more germane to
typical novice users (and less algorithm-y). Wouldn't starting them
off with string processing or simple calculations be a practical way
to get comfortable with the language?

--David

On Jul 3, 9:05?am, kj <no.em... at please.post> wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse. ?I'd love your opinion about
> it.
>
> The context is the concept of a binary search. ?In one of their
> homeworks, my students will have two occasions to use a binary
> search. ?This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.
>
> This seemed straightforward enough, until I realized that, to be
> useful to my students in their homework, this _binary_search function
> had to handle the case in which the passed function was monotonically
> decreasing in the specified interval...
>
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
>
> def _binary_search(lo, hi, func, target, epsilon):
> ? ? assert lo < hi
> ? ? assert epsilon > 0
> ? ? sense = cmp(func(hi), func(lo))
> ? ? if sense == 0:
> ? ? ? ? return None
> ? ? target_plus = sense * target + epsilon
> ? ? target_minus = sense * target - epsilon
> ? ? while True:
> ? ? ? ? param = (lo + hi) * 0.5
> ? ? ? ? value = sense * func(param)
> ? ? ? ? if value > target_plus:
> ? ? ? ? ? ? hi = param
> ? ? ? ? elif value < target_minus:
> ? ? ? ? ? ? lo = param
> ? ? ? ? else:
> ? ? ? ? ? ? return param
>
> ? ? ? ? if lo == hi:
> ? ? ? ? ? ? return None
>
> My question is: is the business with sense and cmp too "clever"?
>
> Here's the rub: the code above is more general (hence more reusable)
> by virtue of this trick with the sense parameter, but it is also
> a bit harder to understand.
>
> This not an unusual situation. ?I find that the processing of
> abstracting out common logic often results in code that is harder
> to read, at least for the uninitiated...
>
> I'd love to know your opinions on this.
>
> TIA!
>
> kj



From nobody at nowhere.com  Mon Jul  6 15:41:53 2009
From: nobody at nowhere.com (Nobody)
Date: Mon, 06 Jul 2009 20:41:53 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
Message-ID: <pan.2009.07.06.19.41.52.828000@nowhere.com>

On Mon, 06 Jul 2009 20:41:03 +0300, jack catcher (nick) wrote:

>> Does the webcam just deliver frames, or are you getting frames out of
>> a decoder layer?  If it's the latter, you want to distribute the encoded
>> video, which should be much lower bandwidth.  Exactly how you do that
>> depends a bit on what format the webcam claims to deliver.
> 
> Well, getting already encoded video from the webcam sounds almost like a 
> free lunch (which it probably is not). At least I wouldn't want to get 
> too long a delay because of the encoding.
> 
> I haven't got the webcam(s) yet, and I guess I can basically purchase 
> any ones I find suitable for getting the job done. Any recommendations?

The webcam is bound to do some encoding; most of them use USB "full speed"
(12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.

Chroma subsampling and JPEG compression will both reduce the bandwidth
without introducing noticable latency (the compression time will be no
more than one frame).

Temporal compression will reduce the bandwidth further. Using B-frames
(frames which contain the differences from a predicted frame which is
based upon both previous and subsequent frames) will provide more 
compression, but increases the latency significantly. For this reason, the
compression built into video cameras normally only uses P-frames (frames
which contain the differences from a predicted frame which is based only
upon previous frames).

The biggest issue is likely to be finding latency specifications, followed
by finding a camera which meets your latency requirement.

Also, any "read frame, write frame" loops will add an additional frame of
latency, as you can't start writing the first byte of the frame until
after you've read the last byte of the frame. Video APIs which let you get
rows as they're decoded are rare.



From sisibley at gmail.com  Mon Jul  6 15:43:40 2009
From: sisibley at gmail.com (Scott Sibley)
Date: Mon, 6 Jul 2009 14:43:40 -0500
Subject: Ctypes to wrap libusb-1.0
Message-ID: <cb4d391b0907061243pb47a240jf5288b6fef33cce5@mail.gmail.com>

I have been having issues trying to wrap libusb-1.0 with ctypes. Actually,
there's not much of an issue if I keep everything synchronous, but I need
this to be asynchronous and that is where my problem arises.

Please refer to the following link on Stackoverflow for a full overview of
the issue.

http://stackoverflow.com/questions/1060305/usb-sync-vs-async-vs-semi-async-partially-answered-now

As mentioned in the question on Stackoverflow, synchronous transfers work
great. I wrote an asynchronous C version that works fine. usbmon's output
suggests the transfers are making it through. libusb's debug output shows
nothing out of the ordinary.

I've also asked about this on the libusb mailing list. I've hesitated asking
on the Python mailing list up till now.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/3ef132cd/attachment.html>

From tjreedy at udel.edu  Mon Jul  6 15:55:02 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 15:55:02 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>
Message-ID: <h2tkqm$tlr$1@ger.gmane.org>

Mark Dickinson wrote:
> On Jul 6, 3:32 am, Lawrence D'Oliveiro <l... at geek-
> central.gen.new_zealand> wrote:
>> I wonder how many people have been tripped up by the fact that
>>
>>     ++n
>>
>> and
>>
>>     --n
>>
>> fail silently for numeric-valued n.

Rather few, it seems.

> Recent python-ideas discussion on this subject:
> 
> http://mail.python.org/pipermail/python-ideas/2009-March/003741.html

To add to what I wrote in that thread: it is C, not Python, that is out 
of step with standard usage in math and most languages. --x = x; 1/1/x = 
x; non not a = a; inverse(inverse(f)) = f; etc. And ++x= +x = x 
corresponded to I(I(x)) = I(x) = x, where I is identity function.

In C as high-level assembler, the inc and dec functions are written as 
-- and ++ operators for some mix of the following reasons. 1) They 
correspond to machine language / assembler functions. 2) They need to be 
efficient since they are used in inner loops. Function calls have 
overhead. Original C did not allow inlining of function calls as best I 
remember. 3) They save keystrokes; 4) 2 versions that return pre and 
post change values are needed. My impression is that some opcode sets 
(and hence assemblers) have only one, and efficient code requires 
allowing direct access to whichever one a particular processor supports. 
Basic routines can usually be written either way.

These reasons do not apply to Python or do not fit Python's style.
Anyone who spends 15 minutes skimming the chapter on expressions could 
notice that 5.5. Unary arithmetic and bitwise operations has only +,-, 
and ~ or that the Summary operator table at the end has no -- or ++.

Terry Jan Reedy



From solipsis at pitrou.net  Mon Jul  6 15:58:26 2009
From: solipsis at pitrou.net (Antoine Pitrou)
Date: Mon, 6 Jul 2009 19:58:26 +0000 (UTC)
Subject: Tree structure consuming lot of memory
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
Message-ID: <loom.20090706T195009-310@post.gmane.org>

mayank gupta <mooniitk <at> gmail.com> writes:
> 
> After a little analysis, I found out that in general it uses about
> 1.4 kb of memory for each node!!

How did you measure memory use? Python objects are not very compact, but 1.4KB
per object seems a bit too much (I would expect more about 150-200 bytes/object
in 32-bit mode, or 300-400 bytes/object in 64-bit mode).

One of the solutions is to use __slots__ as already suggested. Another, which
will have similar benefits, is to use a namedtuple. Both suppress the instance
dictionnary (`instance`.__dict__), which is a major contributor to memory
consumption. Illustration (64-bit mode, by the way):

>>> import sys
>>> from collections import namedtuple

# First a normal class
>>> class Node(object): pass
... 
>>> o = Node()
>>> o.value = 1
>>> o.children = ()
>>> 
>>> sys.getsizeof(o)
64
>>> sys.getsizeof(o.__dict__)
280
# The object seems to take a mere 64 bytes, but the attribute dictionnary
# adds a whoppy 280 bytes and bumps actual size to 344 bytes!

# Now a namedtuple (a tuple subclass with property accessors for the various
# tuple items)
>>> Node = namedtuple("Node", "value children")
>>> 
>>> o = Node(value=1, children=())
>>> sys.getsizeof(o)
72
>>> sys.getsizeof(o.__dict__)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'Node' object has no attribute '__dict__'

# The object doesn't have a __dict__, so 72 bytes is its real total size.




From tjreedy at udel.edu  Mon Jul  6 16:27:25 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 16:27:25 -0400
Subject: updating, adding new pages to confluence remotely, using python
In-Reply-To: <c5ce5132-f4bd-46dc-938c-d4d6fd4dc5b6@x6g2000prc.googlegroups.com>
References: <c5ce5132-f4bd-46dc-938c-d4d6fd4dc5b6@x6g2000prc.googlegroups.com>
Message-ID: <h2tmnd$40c$1@ger.gmane.org>

pescadero10 wrote:
> 
> I am new to python and have been trying to figure out how to remotely
> add new pages to my confluence
> wiki space. I'm running my python script from a linux rhel4 machine
> and using confluence version 2.10. As a test I tried to read from
> stdin and write a page but it fails- that is, the script runs without
> errors but nothing is added.  Does anyone have an example of how this
> is done?  Here is my script:
> 
> --- begin script -----------
> #!/usr/local/bin/python
> #
> # Reads from standard input, dumps it onto a Confluence page
> # You'll need to modify the URL/username/password/spacekey/page title
> # below, because I'm too lazy to bother with argv.
> 
> import sys
> from xmlrpclib import Server
> 
> # Read the text of the page from standard input
> content = sys.stdin.read()
> 
> s = Server("http://confluence.slac.stanford.edu/display/GO/Home")
> token = s.confluence1.login("chee", "******")
> page = s.confluence1.getPage(token, "SPACEKEY", "TEST Python-2-
> Confluence")
> page["content"] = content
> s.confluence1.storePage(token, page)
> 
> newpagedata = {"title":"New Page","content":"new
> content","space":"spaceKey"}
> newpage = s.confluence1.storePage(token, newpagedata);
> ------------ end script ------------------------
> 
> Any help would be greatly appreciated.

You neglected to specify Python version.

As near as I can tell from 2.x docs, xmlrpclib has ServerProxy class but 
no Server class. Whoops, just saw "Server is retained as an alias for 
ServerProxy for backwards compatibility. New code should use 
ServerProxy". Good idea -- calling a client 'server' is confusing.

Do you have access to logs on remote machine to see what was received? 
Or to a sysadmin?

tjr



From mooniitk at gmail.com  Mon Jul  6 16:30:28 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Tue, 7 Jul 2009 02:00:28 +0530
Subject: Tree structure consuming lot of memory
In-Reply-To: <loom.20090706T195009-310@post.gmane.org>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<loom.20090706T195009-310@post.gmane.org>
Message-ID: <ff4d16090907061330g48dd9efbr29d2ae4c6622b73b@mail.gmail.com>

I worked out a small code which initializes about 1,000,000 nodes with some
attributes, and saw the memory usage on my linux machine (using 'top'
command). Then just later I averaged out the memory usage per node. I know
this is not the most accurate way but just for estimated value.

The kind of Node class I am working on in my original code is like :

class Node:
     def __init__(self, #attributes ):
             self.coordinates = coordinates
             self.index = index
             self.sibNum = sibNum
             self.branchNum - branchNum

#here 'coordinates' and 'index' are LISTS with length = "dimension", where
"dimension" is a user-input.

The most shocking part of it after the memory-analysis was that, the memory
usage was never dependent on the "dimension". Yeah it varied a bit, but
there wasnt any significant changes in the memory usage even when the
"dimension" was doubled

-- Any clues?

Thank you for all your suggestions till this point.

Regards.




On Tue, Jul 7, 2009 at 1:28 AM, Antoine Pitrou <solipsis at pitrou.net> wrote:

> mayank gupta <mooniitk <at> gmail.com> writes:
> >
> > After a little analysis, I found out that in general it uses about
> > 1.4 kb of memory for each node!!
>
> How did you measure memory use? Python objects are not very compact, but
> 1.4KB
> per object seems a bit too much (I would expect more about 150-200
> bytes/object
> in 32-bit mode, or 300-400 bytes/object in 64-bit mode).
>
> One of the solutions is to use __slots__ as already suggested. Another,
> which
> will have similar benefits, is to use a namedtuple. Both suppress the
> instance
> dictionnary (`instance`.__dict__), which is a major contributor to memory
> consumption. Illustration (64-bit mode, by the way):
>
> >>> import sys
> >>> from collections import namedtuple
>
> # First a normal class
> >>> class Node(object): pass
> ...
> >>> o = Node()
> >>> o.value = 1
> >>> o.children = ()
> >>>
> >>> sys.getsizeof(o)
> 64
> >>> sys.getsizeof(o.__dict__)
> 280
> # The object seems to take a mere 64 bytes, but the attribute dictionnary
> # adds a whoppy 280 bytes and bumps actual size to 344 bytes!
>
> # Now a namedtuple (a tuple subclass with property accessors for the
> various
> # tuple items)
> >>> Node = namedtuple("Node", "value children")
> >>>
> >>> o = Node(value=1, children=())
> >>> sys.getsizeof(o)
> 72
> >>> sys.getsizeof(o.__dict__)
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
> AttributeError: 'Node' object has no attribute '__dict__'
>
> # The object doesn't have a __dict__, so 72 bytes is its real total size.
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/e92881d3/attachment.html>

From thebrasse at gmail.com  Mon Jul  6 16:36:59 2009
From: thebrasse at gmail.com (brasse)
Date: Mon, 6 Jul 2009 13:36:59 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
Message-ID: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>

Hello!

I have been thinking about how write exception safe constructors in
Python. By exception safe I mean a constructor that does not leak
resources when an exception is raised within it. The following is an
example of one possible way to do it:

class Foo(object):
    def __init__(self, name, fail=False):
        self.name = name
        if not fail:
            print '%s.__init__(%s)' % (self.__class__.__name__,
self.name)
        else:
            print '%s.__init__(%s), FAIL' % (self.__class__.__name__,
                                             self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)

class Bar(object):
    def __init__(self):
        try:
            self.a = Foo('a')
            self.b = Foo('b', fail=True)
        except:
            self.close()


    def close(self):
        if hasattr(self, 'a'):
            self.a.close()
        if hasattr(self, 'b'):
            self.b.close()

bar = Bar()

As you can see this is less than straight forward. Is there some kind
of best practice that I'm not aware of?

:.:: mattias


From no.email at please.post  Mon Jul  6 16:40:49 2009
From: no.email at please.post (kj)
Date: Mon, 6 Jul 2009 20:40:49 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
Message-ID: <h2tngh$12s$1@reader1.panix.com>

In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:

>kj a ?crit :
>(snipo
>> To have a special-case
>> re.match() method in addition to a general re.search() method is
>> antithetical to language minimalism,

>FWIW, Python has no pretention to minimalism.

Assuming that you mean by this that Python's authors have no such
pretensions:

"There is real value in having a small language."

			Guido van Rossum, 2007.07.03
			http://mail.python.org/pipermail/python-3000/2007-July/008663.html

So there.

BTW, that's just one example.  I've seen similar sentiments expressed
by Guido over and over and over: any new proposed enhancement to
Python must be good enough in his mind to justify cluttering the
language.  That attitude counts as minimalism in my book.

The best explanation I have found so far for re.match is that it
is an unfortunate bit of legacy, something that would not be there
if the design of Python did not have to be mindful of keeping old
code chugging along...

kj


From joshua at joshuakugler.com  Mon Jul  6 16:45:45 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Mon, 06 Jul 2009 12:45:45 -0800
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
Message-ID: <h2tnpp$6if$1@ger.gmane.org>

Paul Moore wrote:
> The SQLite documentation mentions a flag, SQLITE_OPEN_READONLY, to
> open a database read only. I can't find any equivalent documented in
> the Python standard library documentation for the sqlite3 module (or,
> for that matter, on the pysqlite library's website).
> 
> Is it possible to open a sqlite database in readonly mode, in Python?

Yes, but most likely not with pysqlite.  The python sqlite3 module in the
standard library, and the pysqlite module are both DB-API compliant, which
means they probably do not have a method to open the DB read only (as that
is usually enforced at the user permission level).

If you want to use that flag, take a look at APSW. It is a very thin layer
on top of the SQLite C API, and thus supports everything that the C API
supports.  It is not, however, DB API compliant, but is very close so not
hard to pick up.

BTW, APSW is written by the same author as pysqlite.

j




From clp2 at rebertia.com  Mon Jul  6 17:03:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 14:03:48 -0700
Subject: Tree structure consuming lot of memory
In-Reply-To: <ff4d16090907061330g48dd9efbr29d2ae4c6622b73b@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<loom.20090706T195009-310@post.gmane.org>
	<ff4d16090907061330g48dd9efbr29d2ae4c6622b73b@mail.gmail.com>
Message-ID: <50697b2c0907061403s16c0602cp5d3767772e6e8ba@mail.gmail.com>

> On Tue, Jul 7, 2009 at 1:28 AM, Antoine Pitrou <solipsis at pitrou.net> wrote:
>>
>> mayank gupta <mooniitk <at> gmail.com> writes:
>> >
>> > After a little analysis, I found out that in general it uses about
>> > 1.4 kb of memory for each node!!
>>
>> How did you measure memory use? Python objects are not very compact, but
>> 1.4KB
>> per object seems a bit too much (I would expect more about 150-200
>> bytes/object
>> in 32-bit mode, or 300-400 bytes/object in 64-bit mode).
>>
>> One of the solutions is to use __slots__ as already suggested. Another,
>> which
>> will have similar benefits, is to use a namedtuple. Both suppress the
>> instance
>> dictionnary (`instance`.__dict__), which is a major contributor to memory
>> consumption. Illustration (64-bit mode, by the way):
>>
>> >>> import sys
>> >>> from collections import namedtuple
>>
>> # First a normal class
>> >>> class Node(object): pass
>> ...
>> >>> o = Node()
>> >>> o.value = 1
>> >>> o.children = ()
>> >>>
>> >>> sys.getsizeof(o)
>> 64
>> >>> sys.getsizeof(o.__dict__)
>> 280
>> # The object seems to take a mere 64 bytes, but the attribute dictionnary
>> # adds a whoppy 280 bytes and bumps actual size to 344 bytes!
>>
>> # Now a namedtuple (a tuple subclass with property accessors for the
>> various
>> # tuple items)
>> >>> Node = namedtuple("Node", "value children")
>> >>>
>> >>> o = Node(value=1, children=())
>> >>> sys.getsizeof(o)
>> 72
>> >>> sys.getsizeof(o.__dict__)
>> Traceback (most recent call last):
>> ?File "<stdin>", line 1, in <module>
>> AttributeError: 'Node' object has no attribute '__dict__'
>>
>> # The object doesn't have a __dict__, so 72 bytes is its real total size.
On Mon, Jul 6, 2009 at 1:30 PM, mayank gupta<mooniitk at gmail.com> wrote:
> I worked out a small code which initializes about 1,000,000 nodes with some
> attributes, and saw the memory usage on my linux machine (using 'top'
> command). Then just later I averaged out the memory usage per node. I know
> this is not the most accurate way but just for estimated value.

You should try the more accurate sys.getsizeof() function:
http://docs.python.org/library/sys.html#sys.getsizeof

Cheers,
Chris

P.S. Please don't top-post in the future.
-- 
http://blog.rebertia.com


From deets at nospam.web.de  Mon Jul  6 17:10:28 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 06 Jul 2009 23:10:28 +0200
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <7bf7i4F2350o5U1@mid.uni-berlin.de>

kj schrieb:
> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
> 
>> kj a ?crit :
>> (snipo
>>> To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism,
> 
>> FWIW, Python has no pretention to minimalism.
> 
> Assuming that you mean by this that Python's authors have no such
> pretensions:
> 
> "There is real value in having a small language."
> 
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
> 
> So there.
> 
> BTW, that's just one example.  I've seen similar sentiments expressed
> by Guido over and over and over: any new proposed enhancement to
> Python must be good enough in his mind to justify cluttering the
> language.  That attitude counts as minimalism in my book.
> 
> The best explanation I have found so far for re.match is that it
> is an unfortunate bit of legacy, something that would not be there
> if the design of Python did not have to be mindful of keeping old
> code chugging along...

language != libraries.

Diez


From Scott.Daniels at Acm.Org  Mon Jul  6 17:15:44 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 14:15:44 -0700
Subject: Cleaning up after failing to contructing objects
In-Reply-To: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
Message-ID: <MeqdnTn37r9N-s_XnZ2dnUVZ_jCdnZ2d@pdx.net>

brasse wrote:
> I have been thinking about how write exception safe constructors in
> Python. By exception safe I mean a constructor that does not leak
> resources when an exception is raised within it. 
...
 > As you can see this is less than straight forward. Is there some kind
 > of best practice that I'm not aware of?

Not so tough.  Something like this tweaked version of your example:

class Foo(object):
     def __init__(self, name, fail=False):
         self.name = name
         if not fail:
             print '%s.__init__(%s)' % (type(self).__name__, name)
         else:
             print '%s.__init__(%s), FAIL' % (type(self).__name__, name)
             raise ValueError('Asked to fail: %r' % fail)

     def close(self):
         print '%s.close(%s)' % (type(self).__name__, self.name)


class Bar(object):
     def __init__(self):
         unwind = []
         try:
             self.a = Foo('a')
             unwind.append(a)
             self.b = Foo('b', fail=True)
             unwind.append(b)
             ...
         except Exception, why:
             while unwind):
                 unwind.pop().close()
             raise

bar = Bar()

--Scott David Daniels
Scott.Daniels at Acm.Org


From macaodha at gmail.com  Mon Jul  6 17:36:37 2009
From: macaodha at gmail.com (Oisin)
Date: Mon, 6 Jul 2009 14:36:37 -0700 (PDT)
Subject: getting text from webpage that has embedded flash
Message-ID: <8aaca352-e115-4aa8-b76d-a37a0edf7a74@h31g2000yqd.googlegroups.com>

HI,

Im trying to parse a bands myspace page and get the total number of
plays for their songs. e.g. http://www.myspace.com/mybloodyvalentine

The problem is that I cannot use urllib2 as the "Total plays" string
does not appear in the page source.

Any idea of ways around this?

Thanks,
O


From michaelmossey at gmail.com  Mon Jul  6 17:37:53 2009
From: michaelmossey at gmail.com (Michael Mossey)
Date: Mon, 6 Jul 2009 14:37:53 -0700 (PDT)
Subject: Catching control-C
Message-ID: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>

What is required in a python program to make sure it catches a control-
c on the command-line? Do some i/o? The OS here is Linux.

Thanks,
Mike


From clp2 at rebertia.com  Mon Jul  6 17:44:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 14:44:20 -0700
Subject: Catching control-C
In-Reply-To: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
Message-ID: <50697b2c0907061444x1a361d47j7c3eeb610431a8ba@mail.gmail.com>

On Mon, Jul 6, 2009 at 2:37 PM, Michael Mossey<michaelmossey at gmail.com> wrote:
> What is required in a python program to make sure it catches a control-
> c on the command-line? Do some i/o? The OS here is Linux.

try:
    #code that reads input
except KeyboardInterrupt:
    #Ctrl-C was pressed

Cheers,
Chris
-- 
http://blog.rebertia.com


From philip at semanchuk.com  Mon Jul  6 17:47:57 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 17:47:57 -0400
Subject: Catching control-C
In-Reply-To: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
Message-ID: <928186A7-E76E-4BF3-8696-DC61ED025B99@semanchuk.com>


On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:

> What is required in a python program to make sure it catches a  
> control-
> c on the command-line? Do some i/o? The OS here is Linux.

You can use a try/except to catch a KeyboardInterrupt exception, or  
you can trap it using the signal module:
http://docs.python.org/library/signal.html

You want to trap SIGINT.


HTH
Philip


From michaelmossey at gmail.com  Mon Jul  6 18:02:26 2009
From: michaelmossey at gmail.com (Michael Mossey)
Date: Mon, 6 Jul 2009 15:02:26 -0700 (PDT)
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
Message-ID: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>

On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>
> > What is required in a python program to make sure it catches a ?
> > control-
> > c on the command-line? Do some i/o? The OS here is Linux.
>
> You can use a try/except to catch a KeyboardInterrupt exception, or ?
> you can trap it using the signal module:http://docs.python.org/library/signal.html
>
> You want to trap SIGINT.
>
> HTH
> Philip

Thanks to both of you. However, my question is also about whether I
need to be doing i/o or some similar operation for my program to
notice in any shape or form that Control-C has been pressed. In the
past, I've written Python programs that go about their business
ignoring Ctrl-C. Other programs respond to it immediately by exiting.
I think the difference is that the latter programs are doing i/o. But
I want to understand better what the "secret" is to responding to a
ctrl-C in any shape or form.

For example, does trapping SIGINT always work, regardless of what my
process is doing?

Thanks,
Mike


From nile_mcadams at yahoo.com  Mon Jul  6 18:02:45 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Mon, 6 Jul 2009 15:02:45 -0700 (PDT)
Subject: Semi-Newbie needs a little help
Message-ID: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>

I am trying to write a simple little program to do some elementary
stock market analysis.  I read lines, send each line to a function and
then the function returns a date which serves as a key to a
dictionary. Each time a date is returned I want to increment the value
associated with that date. The function seems to be working properly.
By means of a print statement I have inserted just before the return
value I can see there are three dates that are returned which is
correct.  The dictionary only seems to capture the last date. My test
data consists of five stocks, each stock with five days. The correct
answer would be a count of 5 for the second day, the third day, and
the last day -- 11/14/2008.

Here is the a code, followed by a portion of the output.  I know
enough to write simple little programs like this with no problems up
until now but I don't know enough to figure out what I am doing
wrong.

Code

    for x in range(len(file_list)):
    d = open(file_list[x] , "r")
    data = d.readlines()
    k = above_or_below(data)                                # This
function seems to work correctly
    print "here is the value that was returned " , k
    dict[k] = dict.get(k,0) + 1

    dict_list = dict.values()
    print "here is a list of the dictionary values ", dict_list
    print "the length of the dictionary is ", len(dict)

And here is some output
    Function will return k which = 11/11/2008   #  These 3 lines are
printed from the function just before the return
    Function will return k which = 11/12/2008   #   This sample shows
stocks 4 and 5 but 1,2,3 are the same.
    Function will return k which = 11/14/2008
    here is the value that was returned 11/14/2008     # printed from
code above  - only the last day seems to be
    Function will return k which = 11/11/2008             #
recognized.
    Function will return k which = 11/12/2008
    Function will return k which = 11/14/2008
    here is the value that was returned 11/14/2008
    here is a list of the dictionary values [5]             # dict has
counted only the last day for 5 stocks
    the length of the dictionary is 1
    >Exit code: 0





From philip at semanchuk.com  Mon Jul  6 18:16:06 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 18:16:06 -0400
Subject: Catching control-C
In-Reply-To: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <A9CD4C3C-0617-48D8-BC29-2D2E2E1BF6D2@semanchuk.com>


On Jul 6, 2009, at 6:02 PM, Michael Mossey wrote:

> On Jul 6, 2:47 pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>>
>>> What is required in a python program to make sure it catches a
>>> control-
>>> c on the command-line? Do some i/o? The OS here is Linux.
>>
>> You can use a try/except to catch a KeyboardInterrupt exception, or
>> you can trap it using the signal module:http://docs.python.org/library/signal.html
>>
>> You want to trap SIGINT.
>>
>> HTH
>> Philip
>
> Thanks to both of you. However, my question is also about whether I
> need to be doing i/o or some similar operation for my program to
> notice in any shape or form that Control-C has been pressed. In the
> past, I've written Python programs that go about their business
> ignoring Ctrl-C. Other programs respond to it immediately by exiting.
> I think the difference is that the latter programs are doing i/o. But
> I want to understand better what the "secret" is to responding to a
> ctrl-C in any shape or form.
>
> For example, does trapping SIGINT always work, regardless of what my
> process is doing?

Hi Mike,
Sorry, I don't know the Python internals well enough to answer your  
question.

Good luck
Philip



From clp2 at rebertia.com  Mon Jul  6 18:22:54 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 15:22:54 -0700
Subject: Semi-Newbie needs a little help
In-Reply-To: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>

On Mon, Jul 6, 2009 at 3:02 PM, Nile<nile_mcadams at yahoo.com> wrote:
> I am trying to write a simple little program to do some elementary
> stock market analysis. ?I read lines, send each line to a function and
> then the function returns a date which serves as a key to a
> dictionary. Each time a date is returned I want to increment the value
> associated with that date. The function seems to be working properly.
> By means of a print statement I have inserted just before the return
> value I can see there are three dates that are returned which is
> correct. ?The dictionary only seems to capture the last date. My test
> data consists of five stocks, each stock with five days. The correct
> answer would be a count of 5 for the second day, the third day, and
> the last day -- 11/14/2008.
>
> Here is the a code, followed by a portion of the output. ?I know
> enough to write simple little programs like this with no problems up
> until now but I don't know enough to figure out what I am doing
> wrong.

> ? ?for x in range(len(file_list)):

for filename in file_list:
#I'm assuming the lack of indentation on the subsequent lines is a
mere transcription error...

> ? ?d = open(file_list[x] , "r")

    d = open(filename , "r")

> ? ?data = d.readlines()
> ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> function seems to work correctly
> ? ?print "here is the value that was returned " , k
> ? ?dict[k] = dict.get(k,0) + 1

`dict` is the name of a builtin type. Please rename this variable to
avoid shadowing the type.
Also, where is this variable even initialized? It's not in this code
snippet you gave.
Further, I would recommend using a defaultdict
(http://docs.python.org/dev/library/collections.html#collections.defaultdict)
rather than a regular dictionary; this would make the
count-incrementing part nicer.

Taking these changes into account, your code becomes:

from collections import defaultdict

counts = defaultdict(lambda: 0)

for filename in file_list:
    d = open(filename , "r")
    data = d.readlines()
    k = above_or_below(data) # This function seems to work correctly
    print "here is the value that was returned " , k
    counts[k] += 1

    values = counts.values()
    print "here is a list of the dictionary values ", values
    print "the length of the dictionary is ", len(counts)


I don't immediately see what's causing your problem, but guess that it
might've be related to the initialization of the `dict` variable.

Cheers,
Chris
-- 
http://blog.rebertia.com


From tn.pablo at gmail.com  Mon Jul  6 18:30:21 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Mon, 6 Jul 2009 17:30:21 -0500
Subject: Semi-Newbie needs a little help
In-Reply-To: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <fdd00b510907061530g42c6599er6f689c84ca59ca68@mail.gmail.com>

On Mon, Jul 6, 2009 at 17:02, Nile<nile_mcadams at yahoo.com> wrote:
> Code
>
> ? ?for x in range(len(file_list)):
> ? ?d = open(file_list[x] , "r")
> ? ?data = d.readlines()
> ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> function seems to work correctly
> ? ?print "here is the value that was returned " , k
> ? ?dict[k] = dict.get(k,0) + 1
>
> ? ?dict_list = dict.values()
> ? ?print "here is a list of the dictionary values ", dict_list
> ? ?print "the length of the dictionary is ", len(dict)

Correcting your indentation errors and moving your comments above the
line they reference will attract more help from others in this list
;-)

Also, I'd recommend limiting your line length to 80 chars, since lines
are wrapped anyway.


-- 
Pablo Torres N.


From bcharrow at csail.mit.edu  Mon Jul  6 18:38:12 2009
From: bcharrow at csail.mit.edu (Ben Charrow)
Date: Mon, 06 Jul 2009 18:38:12 -0400
Subject: Catching control-C
In-Reply-To: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <4A527CD4.3010406@csail.mit.edu>

Michael Mossey wrote:
> On Jul 6, 2:47 pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>> 
>>> What is required in a python program to make sure it catches a control- 
>>> c on the command-line? Do some i/o? The OS here is Linux.
>> You can use a try/except to catch a KeyboardInterrupt exception, or you 
>> can trap it using the signal 
>> module:http://docs.python.org/library/signal.html
>> 
>> You want to trap SIGINT.
>> 
>> HTH Philip
> 
> Thanks to both of you. However, my question is also about whether I need to 
> be doing i/o or some similar operation for my program to notice in any shape
>  or form that Control-C has been pressed.

You don't need to be doing I/O in order to raise a KeyboardIneterrupt.  For
example, the following program should use up a lot of your CPU until you
hit Ctrl-C.

>>> while True:
...     pass
...
^CTraceback (most recent call last):
  File "<stdin>", line 1, in <module>
KeyboardInterrupt

> In the past, I've written Python programs that go about their business 
> ignoring Ctrl-C.

Can you be more specific?  Can you share the relevant sections of these
programs?  Were these programs multi-threaded?

> But I want to understand better what the "secret" is to responding to a 
> ctrl-C in any shape or form.

Strictly speaking, I don't think you can always respond to a Ctrl-C in any
shape or form.  Quoting from the signal module:

Although Python signal handlers are called asynchronously as far as the Python
user is concerned, they can only occur between the "atomic" instructions of the
Python interpreter. This means that signals arriving during long calculations
implemented purely in C (such as regular expression matches on large bodies of
text) may be delayed for an arbitrary amount of time.

HTH,
Ben



From python at mrabarnett.plus.com  Mon Jul  6 18:49:41 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 23:49:41 +0100
Subject: Semi-Newbie needs a little help
In-Reply-To: <50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>
Message-ID: <4A527F85.7030400@mrabarnett.plus.com>

Chris Rebert wrote:
> On Mon, Jul 6, 2009 at 3:02 PM, Nile<nile_mcadams at yahoo.com> wrote:
>> I am trying to write a simple little program to do some elementary
>> stock market analysis.  I read lines, send each line to a function and
>> then the function returns a date which serves as a key to a
>> dictionary. Each time a date is returned I want to increment the value
>> associated with that date. The function seems to be working properly.
>> By means of a print statement I have inserted just before the return
>> value I can see there are three dates that are returned which is
>> correct.  The dictionary only seems to capture the last date. My test
>> data consists of five stocks, each stock with five days. The correct
>> answer would be a count of 5 for the second day, the third day, and
>> the last day -- 11/14/2008.
>>
>> Here is the a code, followed by a portion of the output.  I know
>> enough to write simple little programs like this with no problems up
>> until now but I don't know enough to figure out what I am doing
>> wrong.
> 
>>    for x in range(len(file_list)):
> 
> for filename in file_list:
> #I'm assuming the lack of indentation on the subsequent lines is a
> mere transcription error...
> 
>>    d = open(file_list[x] , "r")
> 
>     d = open(filename , "r")
> 
>>    data = d.readlines()
>>    k = above_or_below(data)                                # This
>> function seems to work correctly
>>    print "here is the value that was returned " , k
>>    dict[k] = dict.get(k,0) + 1
> 
> `dict` is the name of a builtin type. Please rename this variable to
> avoid shadowing the type.
> Also, where is this variable even initialized? It's not in this code
> snippet you gave.
> Further, I would recommend using a defaultdict
> (http://docs.python.org/dev/library/collections.html#collections.defaultdict)
> rather than a regular dictionary; this would make the
> count-incrementing part nicer.
> 
> Taking these changes into account, your code becomes:
> 
> from collections import defaultdict
> 
> counts = defaultdict(lambda: 0)
> 
Better is:

counts = defaultdict(int)

> for filename in file_list:
>     d = open(filename , "r")
>     data = d.readlines()
>     k = above_or_below(data) # This function seems to work correctly
>     print "here is the value that was returned " , k
>     counts[k] += 1
> 
>     values = counts.values()
>     print "here is a list of the dictionary values ", values
>     print "the length of the dictionary is ", len(counts)
> 
> 
> I don't immediately see what's causing your problem, but guess that it
> might've be related to the initialization of the `dict` variable.
> 
It might be that the indentation was wrong where the count is
incremented, but I can't tell because none of the lines were shown
indented.


From p.f.moore at gmail.com  Mon Jul  6 18:50:08 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Mon, 6 Jul 2009 23:50:08 +0100
Subject: Opening a SQLite database in readonly mode
In-Reply-To: <h2tnpp$6if$1@ger.gmane.org>
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org>
Message-ID: <79990c6b0907061550o43df92c0qec1fe2c7e49b916@mail.gmail.com>

2009/7/6 Joshua Kugler <joshua at joshuakugler.com>:
> Paul Moore wrote:
>> The SQLite documentation mentions a flag, SQLITE_OPEN_READONLY, to
>> open a database read only. I can't find any equivalent documented in
>> the Python standard library documentation for the sqlite3 module (or,
>> for that matter, on the pysqlite library's website).
>>
>> Is it possible to open a sqlite database in readonly mode, in Python?
>
> Yes, but most likely not with pysqlite. ?The python sqlite3 module in the
> standard library, and the pysqlite module are both DB-API compliant, which
> means they probably do not have a method to open the DB read only (as that
> is usually enforced at the user permission level).
>
> If you want to use that flag, take a look at APSW. It is a very thin layer
> on top of the SQLite C API, and thus supports everything that the C API
> supports. ?It is not, however, DB API compliant, but is very close so not
> hard to pick up.
>
> BTW, APSW is written by the same author as pysqlite.

Excellent, thanks. I'll have to think whether I want the extra
dependency but at least I know it's possible now.

Thanks for the pointer.
Paul.


From nile_mcadams at yahoo.com  Mon Jul  6 18:50:59 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Mon, 6 Jul 2009 15:50:59 -0700 (PDT)
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2725.1246919443.8015.python-list@python.org>
Message-ID: <c251a5aa-aab2-48af-8583-9ff040a0a393@d4g2000yqa.googlegroups.com>

On Jul 6, 5:30?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
> On Mon, Jul 6, 2009 at 17:02, Nile<nile_mcad... at yahoo.com> wrote:
> > Code
>
> > ? ?for x in range(len(file_list)):
> > ? ?d = open(file_list[x] , "r")
> > ? ?data = d.readlines()
> > ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> > function seems to work correctly
> > ? ?print "here is the value that was returned " , k
> > ? ?dict[k] = dict.get(k,0) + 1
>
> > ? ?dict_list = dict.values()
> > ? ?print "here is a list of the dictionary values ", dict_list
> > ? ?print "the length of the dictionary is ", len(dict)
>
> Correcting your indentation errors and moving your comments above the
> line they reference will attract more help from others in this list
> ;-)
>
> Also, I'd recommend limiting your line length to 80 chars, since lines
> are wrapped anyway.
>
> --
> Pablo Torres N.

Yup - Sorry, first post ever - next ones will be better formatted


From piet at cs.uu.nl  Mon Jul  6 18:51:24 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 00:51:24 +0200
Subject: Why is my code faster with append() in a loop than with a large
	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
	<m2r5wtetb0.fsf@cs.uu.nl>
	<U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>
Message-ID: <m2d48de87n.fsf@cs.uu.nl>

>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) wrote:

>SDD>      # No need for global declarations, we alter, not replace

Yes, I know, but I find it neater to do the global declarations, if only
for documentation. And they don't affect the run time, only the compile
time. 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From matt0177 at GMAIL.COM  Mon Jul  6 18:56:40 2009
From: matt0177 at GMAIL.COM (matt0177)
Date: Mon, 6 Jul 2009 15:56:40 -0700 (PDT)
Subject: Python Error from Apress book
Message-ID: <24364269.post@talk.nabble.com>


http://www.nabble.com/file/p24364269/simple_markup2.py simple_markup2.py 
http://www.nabble.com/file/p24364269/util2.py util2.py 

The two above files are from chapter 20 of the Apress book "Beginning Python
>From Novice to Professional". When I try to run the command as outlined in
the book "simple_markup2.py < test_input.txt > test_output.html i get the
following error every time.

File "C:\Python25\Scripts\simple_markup2.py", line 7, in <module> for block
in blocks(sys.stdin):
File "C:\Python25\Scripts\util2.py", line 7, in blocks for line in
lines(file):
File "C:\Python25\Scripts\util2.py", line 2, in lines for line in file:
yield line
IOError: [Errno 9] Bad file descriptor

I've tried this code on two different computers (both winxp, python 2.5.1)
with the same results. when simple_markup2.py is run with only output, it
will correctly write the headers. When you try to add an input file, you get
the error every time, and I have tried every text file known to man,
including the downloadable sample. This has been frustrating me for several
days, any advice would be greatly appreciated. I'm just starting to learn
python so troubleshooting is a sorely lacked skill atm :)

Thanks,

Matt


-- 
View this message in context: http://www.nabble.com/Python-Error-from-Apress-book-tp24364269p24364269.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From hannarosie at gmail.com  Mon Jul  6 18:57:20 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Mon, 6 Jul 2009 15:57:20 -0700
Subject: Write matrix to text file
Message-ID: <564970db0907061557s2c559b3cxaf52859abd2050a3@mail.gmail.com>

Hi,

I'm working with both python and matlab at the moment and I was wondering if
there is an efficient way to take a 2-D array (of 1s and 0s) in python and
write it to a text file such that matlab will be able to create a sparse
matrix from it later.

Thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/64497bc8/attachment.html>

From piet at cs.uu.nl  Mon Jul  6 18:58:00 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 00:58:00 +0200
Subject: Why is my code faster with append() in a loop than with a
	large	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<4A51CD6A.2010106@dejaviewphoto.com>
	<4A52089F.7020301@mrabarnett.plus.com>
	<mailman.2705.1246899107.8015.python-list@python.org>
Message-ID: <m28wj1e7wn.fsf@cs.uu.nl>

>>>>> Dave Angel <davea at ieee.org> (DA) wrote:

>DA> MRAB wrote:
>>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave Angel
>>> wrote:
>>> [snip]
>>>> It would probably save some time to not bother storing the zeroes in the
>>>> list at all.  And it should help if you were to step through a list of
>>>> primes, rather than trying every possible int.  Or at least constrain
>>>> yourself to odd numbers (after the initial case of 2).
>>>> 
>>> Or stop looking for more factors when you've passed the square root of
>>> num. I don't know what effect there'll be on the time if you recalculate
>>> the square root when num changes (expensive calculation vs smaller
>>> search space).
>>> 
>>> </div>
>>> 
>DA> But if I remember the code, it stopped when the quotient is one, which is
>DA> usually sooner than the square root.  And no need to precalculate the
>DA> square root.

That's right. I thought of doing the sqrt trick by testing for num <
factor, i.e."

        if num < factor:
            break
but found out that it is useless, as for each factor found, num is
divided by that factor as many times as possible. Therefore when the
largest prime factor of num has been found, num ends up being 1 and the
loop stops.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nacim_bravo at agilent.com  Mon Jul  6 19:00:39 2009
From: nacim_bravo at agilent.com (nacim_bravo at agilent.com)
Date: Mon, 6 Jul 2009 17:00:39 -0600
Subject: Newbie needs help
In-Reply-To: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>

Dear Python gurus,

If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?

Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment? 

Please let me know, 
nacim




From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:03:00 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:03:00 +0100
Subject: Python and webcam capture delay?
In-Reply-To: <RGq4m.20945$vi5.15615@uutiset.elisa.fi>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
Message-ID: <op.uwn4za1za8ncjz@gnudebst>

On Mon, 06 Jul 2009 18:41:03 +0100, jack catcher (nick) <nomail at thank.you>  
wrote:

> Rhodri James kirjoitti:
>>  Does the webcam just deliver frames, or are you getting frames out of
>> a decoder layer?  If it's the latter, you want to distribute the encoded
>> video, which should be much lower bandwidth.  Exactly how you do that
>> depends a bit on what format the webcam claims to deliver.
>
> Well, getting already encoded video from the webcam sounds almost like a  
> free lunch (which it probably is not). At least I wouldn't want to get  
> too long a delay because of the encoding.

Not so unlikely as you might think, since there are very basic M-JPEG and
MPEG-2 on-chip encoders available, and the webcam will have to do some
compression to get the video data into the computer.  USB is not as fast
as it would like to pretend.

> I haven't got the webcam(s) yet, and I guess I can basically purchase  
> any ones I find suitable for getting the job done. Any recommendations?

Sorry, no.  I'm used to getting my video feeds down fibre-optic cables :-)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Mon Jul  6 19:05:44 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 01:05:44 +0200
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
Message-ID: <m24otpe7jr.fsf@cs.uu.nl>

>>>>> Philip Semanchuk <philip at semanchuk.com> (PS) wrote:

>PS> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:

>>> What is required in a python program to make sure it catches a  control-
>>> c on the command-line? Do some i/o? The OS here is Linux.

>PS> You can use a try/except to catch a KeyboardInterrupt exception, or  you
>PS> can trap it using the signal module:
>PS> http://docs.python.org/library/signal.html

>PS> You want to trap SIGINT.

And make sure threads don't mess up the signal handling.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:16:00 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:16:00 +0100
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <op.uwn5kya6a8ncjz@gnudebst>

On Mon, 06 Jul 2009 21:40:49 +0100, kj <no.email at please.post> wrote:

> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers  
> <bruno.42.desthuilliers at websiteburo.invalid> writes:
>
>> kj a ?crit :
>> (snipo
>>> To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism,
>
>> FWIW, Python has no pretention to minimalism.
>
> Assuming that you mean by this that Python's authors have no such
> pretensions:
>
> "There is real value in having a small language."
>
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html

re.match() is part of the library, not the language.  The standard
library is in no sense of the word small.  It has a mild tendency
to avoid repeating itself, but presumably the stonkingly obvious
optimisation possibilities of re.match() over re.search() are
considered worth the (small) increase in size.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:20:48 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:20:48 +0100
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
Message-ID: <op.uwn5syxha8ncjz@gnudebst>

On Tue, 07 Jul 2009 00:00:39 +0100, <nacim_bravo at agilent.com> wrote:

> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it  
> possible to do such in Python environment? If yes, how to do or what  
> syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible  
> to get this value in Python environment?

Quite possibly, however you're going to have to give us a *lot* more
information before the answers you get will be worth anything at all.
How is "the certain material" represented?  What simulator are you
using?  Which Python environment?  Which Python version for that matter?

We may appear to be mind-readers, but we usually need a bit more
than this to work on.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:23:57 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:23:57 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <4A522C4B.20102@ieee.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<op.uwninxtza8ncjz@gnudebst> <4A522C4B.20102@ieee.org>
Message-ID: <op.uwn5x7dua8ncjz@gnudebst>

On Mon, 06 Jul 2009 17:54:35 +0100, Dave Angel <davea at ieee.org> wrote:

> Rhodri James wrote:
>> Indeed, arguably it's a bug for C compilers to fail to find the valid
>> parsing of "++5" as "+(+5)".  All I can say is that I've never even
>> accidentally typed that in twenty years of C programming.
>>
> But the C language specifically defines the tokenizer as doing a  
> max-match, finding the longest legal token at any point.  That's how  
> many things that would otherwise be ambiguous are well-defined.  For  
> example, if you want to divide two integers, given pointers to them, you  
> need a space between the slash and the start.
>          *p1/*p2    begins a comment,  while   *p1/ *p2   does a division

You know, I've never had that come up either!  My habit of sticking spaces
around binary operators purely for legibility probably helped, but I'm
still a bit boggled.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From nile_mcadams at yahoo.com  Mon Jul  6 19:29:36 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Mon, 6 Jul 2009 16:29:36 -0700 (PDT)
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2724.1246918979.8015.python-list@python.org>
Message-ID: <c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>

On Jul 6, 5:22?pm, Chris Rebert <c... at rebertia.com> wrote:
> On Mon, Jul 6, 2009 at 3:02 PM, Nile<nile_mcad... at yahoo.com> wrote:
> > I am trying to write a simple little program to do some elementary
> > stock market analysis. ?I read lines, send each line to a function and
> > then the function returns a date which serves as a key to a
> > dictionary. Each time a date is returned I want to increment the value
> > associated with that date. The function seems to be working properly.
> > By means of a print statement I have inserted just before the return
> > value I can see there are three dates that are returned which is
> > correct. ?The dictionary only seems to capture the last date. My test
> > data consists of five stocks, each stock with five days. The correct
> > answer would be a count of 5 for the second day, the third day, and
> > the last day -- 11/14/2008.
>
> > Here is the a code, followed by a portion of the output. ?I know
> > enough to write simple little programs like this with no problems up
> > until now but I don't know enough to figure out what I am doing
> > wrong.
> > ? ?for x in range(len(file_list)):
>
> for filename in file_list:
> #I'm assuming the lack of indentation on the subsequent lines is a
> mere transcription error...
>
> > ? ?d = open(file_list[x] , "r")
>
> ? ? d = open(filename , "r")
>
> > ? ?data = d.readlines()
> > ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> > function seems to work correctly
> > ? ?print "here is the value that was returned " , k
> > ? ?dict[k] = dict.get(k,0) + 1
>
> `dict` is the name of a builtin type. Please rename this variable to
> avoid shadowing the type.
> Also, where is this variable even initialized? It's not in this code
> snippet you gave.
> Further, I would recommend using a defaultdict
> (http://docs.python.org/dev/library/collections.html#collections.defau...)
> rather than a regular dictionary; this would make the
> count-incrementing part nicer.
>
> Taking these changes into account, your code becomes:
>
> from collections import defaultdict
>
> counts = defaultdict(lambda: 0)
>
> for filename in file_list:
> ? ? d = open(filename , "r")
> ? ? data = d.readlines()
> ? ? k = above_or_below(data) # This function seems to work correctly
> ? ? print "here is the value that was returned " , k
> ? ? counts[k] += 1
>
> ? ? values = counts.values()
> ? ? print "here is a list of the dictionary values ", values
> ? ? print "the length of the dictionary is ", len(counts)
>
> I don't immediately see what's causing your problem, but guess that it
> might've be related to the initialization of the `dict` variable.
>
> Cheers,
> Chris
> --http://blog.rebertia.com- Hide quoted text -
>
> - Show quoted text -

I initialized the dictionary earlier in the program like this -

  hashtable = {}

I changed the "dict" to hashtable but I still get the same result
I will try to learn about the defaultdict but I'm just trying to keep
it as simple as I can for now

Revised code

for x in range(len(file_list)):
	d = open(file_list[x] , "r")
	data = d.readlines()
	k = 0
	k = above_or_below(data)
	print "here is the value that was returned ",k
	hashtable[k] = hashtable.get(k,0) + 1


hashtable_list = hashtable.values()
print "here is a list of the dictionary values ", hashtable_list
print "the length of the dictionary is ", len(hashtable)

Output
# The first 3 lines are printed from the function
# right before the return statement.  This output
# snippet shows the last two stocks.  The function
# SAYS it is returning the correct value but only
# the last date seems to make it to the hashtable
Function will return k which = 11/11/2008
Function will return k which = 11/12/2008
Function will return k which = 11/14/2008

# this line is printed from the code above
# I don't understand why all three dates don't
# seem to make it to the main program.  Only
# the last date seems to be recognized
here is the value that was returned 11/14/2008

Function will return k which = 11/11/2008
Function will return k which = 11/12/2008
Function will return k which = 11/14/2008
here is the value that was returned 11/14/2008
here is a list of the dictionary values [5]
the length of the dictionary is 1
>Exit code: 0


From python at mrabarnett.plus.com  Mon Jul  6 19:41:53 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 00:41:53 +0100
Subject: Semi-Newbie needs a little help
In-Reply-To: <c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>	<mailman.2724.1246918979.8015.python-list@python.org>
	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
Message-ID: <4A528BC1.4040400@mrabarnett.plus.com>

Nile wrote:
[snip]
> I initialized the dictionary earlier in the program like this -
> 
>   hashtable = {}
> 
> I changed the "dict" to hashtable but I still get the same result
> I will try to learn about the defaultdict but I'm just trying to keep
> it as simple as I can for now
> 
> Revised code
> 
> for x in range(len(file_list)):
> 	d = open(file_list[x] , "r")
> 	data = d.readlines()

What's the point of the following line?

> 	k = 0
> 	k = above_or_below(data)
> 	print "here is the value that was returned ",k
> 	hashtable[k] = hashtable.get(k,0) + 1
> 
> 
> hashtable_list = hashtable.values()
> print "here is a list of the dictionary values ", hashtable_list
> print "the length of the dictionary is ", len(hashtable)
> 
> Output
> # The first 3 lines are printed from the function
> # right before the return statement.  This output
> # snippet shows the last two stocks.  The function
> # SAYS it is returning the correct value but only
> # the last date seems to make it to the hashtable

> Function will return k which = 11/11/2008
> Function will return k which = 11/12/2008
> Function will return k which = 11/14/2008
> 
> # this line is printed from the code above
> # I don't understand why all three dates don't
> # seem to make it to the main program.  Only
> # the last date seems to be recognized
> here is the value that was returned 11/14/2008
> 
> Function will return k which = 11/11/2008
> Function will return k which = 11/12/2008
> Function will return k which = 11/14/2008
> here is the value that was returned 11/14/2008
> here is a list of the dictionary values [5]
> the length of the dictionary is 1
>> Exit code: 0

I think there's a bug in 'above_or_below' which you haven't noticed.


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 19:49:40 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 20:49:40 -0300
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<MeqdnTn37r9N-s_XnZ2dnUVZ_jCdnZ2d@pdx.net>
Message-ID: <op.uwn642w7x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 18:15:44 -0300, Scott David Daniels  
<Scott.Daniels at acm.org> escribi?:

> brasse wrote:
>> I have been thinking about how write exception safe constructors in
>> Python. By exception safe I mean a constructor that does not leak
>> resources when an exception is raised within it.
> ...
>  > As you can see this is less than straight forward. Is there some kind
>  > of best practice that I'm not aware of?
>
> Not so tough.  Something like this tweaked version of your example:

Another variant: Presumably, there is already a method in Bar responsible  
for "normal" cleanup; just make sure it gets called (and write it in a  
robust way):

> class Foo(object):
>      def __init__(self, name, fail=False):
>          self.name = name
>          if not fail:
>              print '%s.__init__(%s)' % (type(self).__name__, name)
>          else:
>              print '%s.__init__(%s), FAIL' % (type(self).__name__, name)
>              raise ValueError('Asked to fail: %r' % fail)
>
>      def close(self):
>          print '%s.close(%s)' % (type(self).__name__, self.name)

class Bar(object):
     a = None # default values
     b = None

     def __init__(self):
         try:
             self.a = Foo('a')
             self.b = Foo('b', fail=True)
         except Exception, why:
             self.cleanup()
             raise

     def cleanup(self):
         if self.a is not None:
             self.a.close()
         if self.b is not None:
             self.b.close()

bar = Bar()

-- 
Gabriel Genellina



From mh at pixar.com  Mon Jul  6 20:21:32 2009
From: mh at pixar.com (mh at pixar.com)
Date: Tue, 07 Jul 2009 00:21:32 GMT
Subject: parsing times like "5 minutes ago"?
Message-ID: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>

I'm looking for something like Tcl's [clock scan] command which parses
human-readable time strings such as:

    % clock scan "5 minutes ago"
    1246925569
    % clock scan "tomorrow 12:00"
    1246993200
    % clock scan "today + 1 fortnight"
    1248135628

Does any such package exist for Python?

Many TIA!
Mark

-- 
Mark Harrison
Pixar Animation Studios


From pavlovevidence at gmail.com  Mon Jul  6 20:43:09 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 6 Jul 2009 17:43:09 -0700 (PDT)
Subject: parsing times like "5 minutes ago"?
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
Message-ID: <d7fea6e2-8f29-4fef-b482-631e83606ec7@q11g2000yqi.googlegroups.com>

On Jul 6, 5:21?pm, m... at pixar.com wrote:
> I'm looking for something like Tcl's [clock scan] command which parses
> human-readable time strings such as:
>
> ? ? % clock scan "5 minutes ago"
> ? ? 1246925569
> ? ? % clock scan "tomorrow 12:00"
> ? ? 1246993200
> ? ? % clock scan "today + 1 fortnight"
> ? ? 1248135628
>
> Does any such package exist for Python?

If you're on a machine with GNU datethe simplest solution is to use it
to parse the string.

Q&D:

def clock_scan(datestring):
    stdout,stderr = subprocess.Popen(
        ['date','+%s','--date=%s' % datestring ],
        stdout=subprocess.PIPE).communicate()
    return float(stdout)


clock_scan('1 hour ago')
clock_scan('next week')


Carl Banks


From rhodri at wildebst.demon.co.uk  Mon Jul  6 20:58:07 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 01:58:07 +0100
Subject: Semi-Newbie needs a little help
In-Reply-To: <c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2724.1246918979.8015.python-list@python.org>
	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
Message-ID: <op.uwoaa5yja8ncjz@gnudebst>

On Tue, 07 Jul 2009 00:29:36 +0100, Nile <nile_mcadams at yahoo.com> wrote:

> Revised code
>
> for x in range(len(file_list)):
> 	d = open(file_list[x] , "r")
> 	data = d.readlines()
> 	k = 0
> 	k = above_or_below(data)
> 	print "here is the value that was returned ",k
> 	hashtable[k] = hashtable.get(k,0) + 1
>
>
> hashtable_list = hashtable.values()
> print "here is a list of the dictionary values ", hashtable_list
> print "the length of the dictionary is ", len(hashtable)
>
> Output
> # The first 3 lines are printed from the function
> # right before the return statement.  This output
> # snippet shows the last two stocks.  The function
> # SAYS it is returning the correct value but only
> # the last date seems to make it to the hashtable
> Function will return k which = 11/11/2008
> Function will return k which = 11/12/2008
> Function will return k which = 11/14/2008

Have you checked the indentation of the print statement
that produces this?  Is it perhaps inside a loop still?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:01:44 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:01:44 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
Message-ID: <006e795f$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:

> kj wrote:
>>  I've rewritten it like this:
>>
>>     sense = cmp(func(hi), func(lo))
>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>
>> Thanks for your feedback!
>>
>> kj
>>   
>>   
> As already said before, unlike other languages, sense in english does
> **not** mean direction. You should rewrite this part using a better
> name. Wrong informations are far worse than no information at all.

Absolutely.

>From Webster's Dictionary:

      8. (Geom.) One of two opposite directions in which a line,
      surface, or volume, may be supposed to be described by the
      motion of a point, line, or surface.
      [1913 Webster]


And from WordNet:

     2: the meaning of a word or expression; the way in which a word
        or expression or situation can be interpreted

Both meanings are relevant to the way KJ is using the word. Please take 
your own advice and stop giving wrong information. As a native English 
speaker, I had no difficulty understanding the meaning of "sense" in the 
sense intended by KJ.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:04:02 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:04:02 GMT
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
	<comdnVhXl4M6bczXnZ2dnUVZ_g2dnZ2d@pdx.net>
Message-ID: <006e79e9$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 05:47:18 -0700, Scott David Daniels wrote:

> Steven D'Aprano wrote:
>> ... That's the Wrong Way to do it --
>> you're using a screwdriver to hammer a nail....
> 
> Don't knock tool abuse (though I agree with you here). Sometimes tool
> abuse can produce good results.  For example, using hammers to drive
> screws for temporary strong holds led to making better nails.

Historically, nails were invented a long time before screws. Screws as 
fasteners weren't invented until the 1400s, nails were used thousands of 
years ago.

And hammering screws makes temporary *weak* holds, not strong, because 
the screw only touches the sides of the hole lightly. Unless the screw 
has been specifically designed to be hammered, hammering screws is pretty 
much the definition of incompetence and/or laziness!


-- 
Steven


From chris at simplistix.co.uk  Mon Jul  6 21:09:41 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 02:09:41 +0100
Subject: Where does setuptools live?
In-Reply-To: <3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
Message-ID: <4A52A055.8080108@simplistix.co.uk>

Floris Bruynooghe wrote:
> It is, see
> http://mail.python.org/pipermail/distutils-sig/2009-July/012374.html
> 
> 
>> It's seen no changes in 9 months.
> 
> It's setuptools...  I'm sure you can find many flamefests on distutils-
> sig about this.

Yeah, distutils-sig is the right place to discuss.

I wonder how close setuptools is to being forked because of Phil Eby's 
unwillingness to apply patches and/or clean up the horrible setuptools code?

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:16:41 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:16:41 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
Message-ID: <006e7ce0$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 16:43:43 +0100, Tim Rowe wrote:

> 2009/7/4 kj <no.email at please.post>:
> 
>> Precisely. ?As I've stated elsewhere, this is an internal helper
>> function, to be called only a few times under very well-specified
>> conditions. ?The assert statements checks that these conditions are as
>> intended. ?I.e. they are checks against the module writer's programming
>> errors.
> 
> Good for you. I'm convinced that you have used the assertion
> appropriately, and the fact that so many here are unable to see that
> looks to me like a good case for teaching the right use of assertions.
> For what it's worth, I read assertions at the beginning of a procedure
> as part of the specification of the procedure, and I use them there in
> order to document the procedure. An assertion in that position is for me
> a statement to the user of the procedure "it's your responsibility to
> make sure that you never call this procedure in such a way as to violate
> these conditions". They're part of a contract, as somebody (maybe you)
> pointed out.
> 
> As somebody who works in the safety-critical domain, it's refreshing to
> see somebody teaching students to think about the circumstances in which
> a procedure can legitimately be called. The hostility you've received to
> that idea is saddening, and indicative of why there's so much buggy
> software out there.

LOL.

Maybe the reason for "so much buggy software" is that people 
inappropriately use assert, thus changing the behaviour of code depending 
on whether it is run with the -O flag or not.

I don't know what "hostility" you're seeing. The only hostility I'm 
seeing is from the OP, which is bizarre considering that he asked for 
advice and we gave it. What I see is a bunch of people concerned that the 
OP is teaching novices a bad habit, namely, using assert for error 
checking. He claims -- angrily and over and over again -- that in his 
code, the assertions should never fail. Great. Good for him for knowing 
when to use assert. But are the novices going to learn that lesson, or 
will they simply learn "use assert for error checking"?



-- 
Steven


From davea at ieee.org  Mon Jul  6 21:18:57 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 21:18:57 -0400
Subject: Semi-Newbie needs a little help
In-Reply-To: <4A528BC1.4040400@mrabarnett.plus.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>	<mailman.2724.1246918979.8015.python-list@python.org>	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
	<4A528BC1.4040400@mrabarnett.plus.com>
Message-ID: <4A52A281.3040101@ieee.org>

MRAB wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Nile wrote:
> [snip]
>> I initialized the dictionary earlier in the program like this -
>>
>>   hashtable = {}
>>
>> I changed the "dict" to hashtable but I still get the same result
>> I will try to learn about the defaultdict but I'm just trying to keep
>> it as simple as I can for now
>>
>> Revised code
>>
>> for x in range(len(file_list)):
>>     d = open(file_list[x] , "r")
>>     data = d.readlines()
>
> What's the point of the following line?
>
>>     k = 0
>>     k = above_or_below(data)
>>     print "here is the value that was returned ",k
>>     hashtable[k] = hashtable.get(k,0) + 1
>>
>>
>> hashtable_list = hashtable.values()
>> print "here is a list of the dictionary values ", hashtable_list
>> print "the length of the dictionary is ", len(hashtable)
>>
>> Output
>> # The first 3 lines are printed from the function
>> # right before the return statement.  This output
>> # snippet shows the last two stocks.  The function
>> # SAYS it is returning the correct value but only
>> # the last date seems to make it to the hashtable
>
>> Function will return k which = 11/11/2008
>> Function will return k which = 11/12/2008
>> Function will return k which = 11/14/2008
>>
>> # this line is printed from the code above
>> # I don't understand why all three dates don't
>> # seem to make it to the main program.  Only
>> # the last date seems to be recognized
>> here is the value that was returned 11/14/2008
>>
>> Function will return k which = 11/11/2008
>> Function will return k which = 11/12/2008
>> Function will return k which = 11/14/2008
>> here is the value that was returned 11/14/2008
>> here is a list of the dictionary values [5]
>> the length of the dictionary is 1
>>> Exit code: 0
>
> I think there's a bug in 'above_or_below' which you haven't noticed.
>
> </div>
>
The code supplied doesn't match the output supplied.  It'd probably help 
if the output was actually pasted from the command window, instead of 
retyped with more comments than data.  And of course it'd help if you 
actually showed us the function above_or_below(), which is probably 
where the bug is.  If it prints three values, but returns a string, then 
why would you be surprised?   Maybe you intended it to return a list?

Each time above_or_below() it's called, it prints three lines before 
returning, but only returns the final value.  How big is file_list?  I 
suspect it's of length 5.

And the output is shown as repeated twice, but it probably was actually 
five sets of data.

You do know you can print hashtable, don't you?  You're extracting and 
printing the values, but not bothering with the keys.

I suggest you add a print to the entry point of above_or_below(), to 
match the one you have for its return.  And all of these print lines 
should be indented.  That might make it easier to interpret the output, 
without lots of inserted comments.

DaveA


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:20:04 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:20:04 GMT
Subject: Newbie needs help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2732.1246922109.8015.python-list@python.org>
Message-ID: <006e7dac$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 17:00:39 -0600, nacim_bravo wrote:

> Dear Python gurus,
> 
> If I'd like to set dielectric constant for the certain material, is it
> possible to do such in Python environment? If yes, how to do or what
> syntax can be used?

certain_material.dielectric_constant = 1.234


> Also, I'd like to get a simulation result, like voltage, is it possible
> to get this value in Python environment?

Yes.



-- 
Steven


From ben.welsh at gmail.com  Mon Jul  6 21:25:13 2009
From: ben.welsh at gmail.com (palewire)
Date: Mon, 6 Jul 2009 18:25:13 -0700 (PDT)
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
Message-ID: <24365710.post@talk.nabble.com>



In my application, I'd like to have a function that compares two values,
either of which may be null, and then classify the result depending on
whether one is higher or lower than the other.

I find myself writing something clunky like this, and I'm curious whether
anyone might know a more elegant way for parsing this out.

def compare(a, b):
    if not a and not b:
        return "No data"
    else:
        if a == 0 and b == 0:
            return "Never had"
        else:
            if a == b:
                return "Stayed the same"
            elif a < b:
                return "Gained"
            elif a > b and b > 0:
                return "Lost Some"
            elif a > b and b == 0:
                return "Lost All"

If there's some obvious way to search for this solution online, feel free to
slap me with that. I tried digging around on Google and couldn't come up
with much.

Thanks much.
-- 
View this message in context: http://www.nabble.com/Looking-for-a-slick-way-to-classify-relationship-between-two-numbers%2C-without-tons-of-if-else-tp24365710p24365710.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From gherron at islandtraining.com  Mon Jul  6 21:29:51 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Mon, 06 Jul 2009 18:29:51 -0700
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
Message-ID: <4A52A50F.1060208@islandtraining.com>

nacim_bravo at agilent.com wrote:
> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment? 
>
> Please let me know, 
> nacim
>   
This would be a good place for you to start:
  http://www.catb.org/~esr/faqs/smart-questions.html


From ldo at geek-central.gen.new_zealand  Mon Jul  6 21:33:18 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 07 Jul 2009 13:33:18 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>
	<mailman.2714.1246910113.8015.python-list@python.org>
Message-ID: <h2u8kv$hdf$2@lust.ihug.co.nz>

In message <mailman.2714.1246910113.8015.python-list at python.org>, Terry 
Reedy wrote:

> ... it is C, not Python, that is out of step with standard usage in math
> and most languages ...

And it is C that introduced "==" for equality, versus "=" for assignment, 
which Python slavishly followed instead of keeping "=" with its mathematical 
meaning and using ":=" for assignment.



From david.lyon at preisshare.net  Mon Jul  6 21:55:03 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Mon, 06 Jul 2009 21:55:03 -0400
Subject: Where does setuptools =?UTF-8?Q?live=3F?=
In-Reply-To: <4A52A055.8080108@simplistix.co.uk>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
Message-ID: <d7a4b1f129accf47d72f18aec329aea8@preisshare.net>

On Tue, 07 Jul 2009 02:09:41 +0100, Chris Withers <chris at simplistix.co.uk>
wrote:
> I wonder how close setuptools is to being forked because of Phil Eby's 
> unwillingness to apply patches and/or clean up the horrible setuptools
> code?

setuptools... as far as I can see isn't actually installed until you
install easyinstall...

Pip (http://pypi.python.org/pypi/pip) and enstall 
(http://pypi.python.org/pypi/Enstaller/3.1.0) seem to be forks of 
setuptools already...

So it looks like it's already been forked to some degree..

What hasn't happened is enough testing of pypi packages and installing
with setuptools/pip/enstall from pypi.

If the xmlrpc links actually "worked" on pypi...

http://wiki.python.org/moin/PyPiXmlRpc?action=show&redirect=CheeseShopXmlRpc

ie.. that they would allow a developer to download a packages via rpc....

then this whole issue could probably be fixed more easily...

ok - the process isn't perfect... 

but there's room for improvement...

David



From rhodri at wildebst.demon.co.uk  Mon Jul  6 22:11:43 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 03:11:43 +0100
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
In-Reply-To: <24365710.post@talk.nabble.com>
References: <24365710.post@talk.nabble.com>
Message-ID: <op.uwodptt9a8ncjz@gnudebst>

On Tue, 07 Jul 2009 02:25:13 +0100, palewire <ben.welsh at gmail.com> wrote:

> In my application, I'd like to have a function that compares two values,
> either of which may be null, and then classify the result depending on
> whether one is higher or lower than the other.
>
> I find myself writing something clunky like this, and I'm curious whether
> anyone might know a more elegant way for parsing this out.

It depends on what you want to do with the information.  If you're doing
different things on each case, you might as well do it with an if-chain,
though you could make it a bit tidier:

> def compare(a, b):
>     if not a and not b:

Did you mean "if a is None or b is None:" here?

>         return "No data"
>     else:
>         if a == 0 and b == 0:

This will never fire, because it will always be
caught by the test above.

>             return "Never had"
>         else:
>             if a == b:
>                 return "Stayed the same"
>             elif a < b:
>                 return "Gained"
>             elif a > b and b > 0:
>                 return "Lost Some"
>             elif a > b and b == 0:
>                 return "Lost All"

def compare(a, b):
     if a is not None and b is not None:
	return "No data"
     elif a == 0 and b == 0:
         return "Never had"
     elif a == b:
         return "Stayed the same"
     elif a < b:
         return "Gained"
     elif b > 0:
         return "Lost Some"
     return "Lost All"


Alternatively you can do something like the (deprecated) cmp and a
dispatch table:

CMP_TABLE = [ "Gained", "Stayed the same", "Lost Some", "Lost All"]

def compare(a, b):
     if a is not None or b is not None:
         return "No data"
     c = cmp(a, b) + 1
     if c == 2 and b == 0:
         c = 3
     return CMP_TABLE[c]

There's no cmp() in Python 3.x so you'd have to roll your own.  At
that point you might as well revert to the if-chain, since it'll be
a lot easier to understand when you come back to it in six months
time.


-- 
Rhodri James *-* Wildebeest Herder to the Masses


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 22:18:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 23:18:37 -0300
Subject: Python Error from Apress book
References: <24364269.post@talk.nabble.com>
Message-ID: <op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com> escribi?:

> When I try to run the command as outlined in
> the book "simple_markup2.py < test_input.txt > test_output.html i get the
> following error every time.
>
> IOError: [Errno 9] Bad file descriptor

That's a Windows problem. When you execute the script as itself (either as  
you do in the command line, or by double-clicking on it), it doesn't have  
valid standard handles.
You have to invoke Python explicitely:

python simple_markup2.py < test_input.txt > test_output.html

(you may need to specify the full path to python.exe, or add the directory  
where Python is installed to your system PATH).

-- 
Gabriel Genellina



From fetchinson at googlemail.com  Mon Jul  6 22:48:39 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Mon, 6 Jul 2009 19:48:39 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <006da5a2$0$9711$c3e8da3@news.astraweb.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>

>>>> I wonder how many people have been tripped up by the fact that
>>>>
>>>>     ++n
>>>>
>>>> and
>>>>
>>>>     --n
>>>>
>>>> fail silently for numeric-valued n.
>>>
>>> What do you mean, "fail silently"? They do exactly what you should
>>> expect:
>>>>>> ++5  # positive of a positive number is positive
>>>
>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>> that are buggy, not Python.
>>
>> Well, those expectations are taken seriously when new features are
>> introduced into the language - and sometimes the feature is dismissed
>> just because it would be confusing for some. If a += 1 works, expecting
>> ++a to have the same meaning is very reasonable (for those coming from
>> languages with a ++ operator, like C or Java) - more when ++a is a
>> perfectly valid expression. If this issue isn't listed under the various
>> "Python gotchas" articles, it should...
>
> The fact that it isn't suggests strongly to me that it isn't that common
> a surprise even for Java and C programmers. This is the first time I've
> seen anyone raise it as an issue.
>
> There are plenty of other languages other than Java and C. If we start
> listing every feature of Python that's different from some other
> language, we'll never end.

Yes, there are plenty of languages other than Java and C, but the
influence of C is admittedly huge in Python. Why do you think loops
are called "for", conditionals "if" or "while", functions return via
"return", loops terminate via "break" and keep going via "continue"
and why is comparison written as "==", etc, etc? All of these are
coming from C (or an even earlier language) and my point is that users
are most of time correct when they assume that something will work the
same way as in C.

So I'd think that putting a warning in a FAQ or a Python Gotchas list
about ++n would be very useful for many users. And it does not imply
that the differences from every other language should be documented in
a similar fashion. Only C :)

Cheers,
Daniel

> For what it's worth, Ruby appears to behave the same as Python:
>
> $ irb
> irb(main):001:0> n = 5
> => 5
> irb(main):002:0> ++n
> => 5
> irb(main):003:0> --n
> => 5
> irb(main):004:0> -+n
> => -5
>


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From astan.chee at al.com.au  Mon Jul  6 22:58:24 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 7 Jul 2009 12:58:24 +1000
Subject: copytree with timeout in windows
Message-ID: <4A52B9D0.9040608@al.com.au>

Hi,
I'm trying to modify the copytree function in shutil so that any file 
being copied does not take more than 5 minutes (if it does, skip to the 
next one). This is what I have so far:

import shutil
import signal, os

def handler(signum, frame):
    print 'Signal handler called with signal', signum
    raise IOError, "Couldn't open device!"

signal.signal(signal.SIGALRM, handler)

def copytree(src, dst):
    names = os.listdir(src)
    os.makedirs(dst)
    signal.alarm(0)
    for name in names:
        if name in ignored_names:
            continue
        srcname = os.path.join(src, name)
        dstname = os.path.join(dst, name)
        try:
            if os.path.isdir(srcname):
                copytree(srcname, dstname, symlinks, ignore)
            else:
                signal.alarm(300)
                shutil.copy2(srcname, dstname)
        except (IOError, os.error), why:
            print str(why)
        # catch the Error from the recursive copytree so that we can
        # continue with other files
        except Error, err:
            print str(err.args[0])

source = "c:\\testwa\\"
destination = "d:\\testwa\\"

copytree(source,destination)

Then I re-read the documentation which said that signal.SIGALRM is 
unix/linux only. How do I go about doing this in windows?
Thanks for any help.
Cheers
Astan




From rocky at gnu.org  Mon Jul  6 23:13:09 2009
From: rocky at gnu.org (rocky)
Date: Mon, 6 Jul 2009 20:13:09 -0700 (PDT)
Subject: module name versus function name resolution conflict.
Message-ID: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>

Someone recently reported a problem in pydb where a function defined
in his program was conflicting with a module name that pydb uses. I
think I understand what's wrong, but I don't have any elegant
solutions to the problem. Suggestions would be appreciated.

In a nutshell, here's the problem:

In file fns:

  def foo(): print "foo"

In file pdebug.py:

  import fns, sys

  def trace_dispatch(frame, event, arg):
      fns.foo()
      print frame, event, arg
      return trace_dispatch

  sys.settrace(trace_dispatch)
  execfile('myprogram.py')

Finally file myprogram.py:

  def fns(): print "This is the *other* fns"

When you run pdebug.py you get:

$ python pdebug.py
foo
<frame object at 0xdd9030> call None
foo
<frame object at 0xdd9030> line None
Traceback (most recent call last):
  File "pdebug.py", line 7, in <module>
    execfile('myprogram.py')
  File "myprogram.py", line 1, in <module>
    def fns(): print "This is the *other* fns"
  File "pdebug.py", line 3, in trace_dispatch
    fns.foo()
AttributeError: 'function' object has no attribute 'foo'


Basically inside the trace hook, local functions are visible and take
precedence over (global) module names. I could move "import fns"
inside trace_dispatch(), but I'd have to do that in all of the methods
that module "fns" is used.  Also note that using the form:
  from fns import foo

would eliminate the conflict on "fns", but I'd still have potential
conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
reduce the chance of a conflict but not eliminate it.

Suggestions?




From davea at ieee.org  Mon Jul  6 23:28:39 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 23:28:39 -0400
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
In-Reply-To: <24365710.post@talk.nabble.com>
References: <24365710.post@talk.nabble.com>
Message-ID: <4A52C0E7.9060502@ieee.org>

palewire wrote:
> In my application, I'd like to have a function that compares two values,
> either of which may be null, and then classify the result depending on
> whether one is higher or lower than the other.
>
> I find myself writing something clunky like this, and I'm curious whether
> anyone might know a more elegant way for parsing this out.
>
> def compare(a, b):
>     if not a and not b:
>         return "No data"
>     else:
>         if a == 0 and b == 0:
>             return "Never had"
>         else:
>             if a == b:
>                 return "Stayed the same"
>             elif a < b:
>                 return "Gained"
>             elif a > b and b > 0:
>                 return "Lost Some"
>             elif a > b and b == 0:
>                 return "Lost All"
>
> If there's some obvious way to search for this solution online, feel free to
> slap me with that. I tried digging around on Google and couldn't come up
> with much.
>
> Thanks much.
>   
Before one can "optimize" a function, one needs to get the function 
correct.  Looks to me that if a and b are both zero, it'll say "No data" 
and never get to the "Never had" test.  And if a is positive and b is 
None, it'll return None, rather than any string.

Anyway, any "optimized" construct is going to be nearly as big as this.  
You'd have to define a list of strings, and then compute an index value 
that gave you the appropriate value.  While I could probably come up 
with such, I hardly think it's worthwhile.  The cases are confusing 
enough to me that I'd not want to make the code any less readable by 
some formula & lookup.

That brings us to the question of what is more elegant.  To me the 
elegant code is readable first, and efficient (space & time) second.  I 
suspect efficiency would be nearly optimal by careful ordering of the 
nested ifs.  Find the most likely cases, and test for them first.

If this is a programming puzzle, for entertainment purposes, here's the 
way I'd tackle making it "efficient" obfuscated code.  Start by checking 
if either value is None.  Something like:

table = ("Lost Some","Lost All","Gained","Gained","Stayed the 
same","Never had, never will")
def compare2(a,b):
    global table
    if a is None or b is None:
        return "Invalid data"
    return table[4*(a==b)+2*(a<b)+(b==0)]

davea


From lasleyse at gmail.com  Mon Jul  6 23:48:36 2009
From: lasleyse at gmail.com (selasley)
Date: Mon, 6 Jul 2009 20:48:36 -0700 (PDT)
Subject: parsing times like "5 minutes ago"?
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
	<d7fea6e2-8f29-4fef-b482-631e83606ec7@q11g2000yqi.googlegroups.com>
Message-ID: <c7bcb0bd-e09d-4aea-8633-249f1e36e183@i6g2000yqj.googlegroups.com>

On Jul 6, 8:43?pm, Carl Banks <pavlovevide... at gmail.com> wrote:
> On Jul 6, 5:21?pm, m... at pixar.com wrote:
>
> > I'm looking for something like Tcl's [clock scan] command which parses
> > human-readable time strings such as:
>
> > ? ? % clock scan "5 minutes ago"
> > ? ? 1246925569
> > ? ? % clock scan "tomorrow 12:00"
> > ? ? 1246993200
> > ? ? % clock scan "today + 1 fortnight"
> > ? ? 1248135628
>
> > Does any such package exist for Python?
>
> If you're on a machine with GNU datethe simplest solution is to use it
> to parse the string.
>
> Q&D:
>
> def clock_scan(datestring):
> ? ? stdout,stderr = subprocess.Popen(
> ? ? ? ? ['date','+%s','--date=%s' % datestring ],
> ? ? ? ? stdout=subprocess.PIPE).communicate()
> ? ? return float(stdout)
>
> clock_scan('1 hour ago')
> clock_scan('next week')
>
> Carl Banks

The timelib module might do what you want
http://pypi.python.org/pypi/timelib/0.2


From tjreedy at udel.edu  Mon Jul  6 23:50:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 23:50:08 -0400
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <h2uglg$u9e$1@ger.gmane.org>

kj wrote:

> "There is real value in having a small language."
> 
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
> 
> So there.

small != minimal

> 
> BTW, that's just one example.  I've seen similar sentiments expressed
> by Guido over and over and over: any new proposed enhancement to
> Python must be good enough in his mind to justify cluttering the
> language.  That attitude counts as minimalism in my book.
> 
> The best explanation I have found so far for re.match is that it
> is an unfortunate bit of legacy, something that would not be there
> if the design of Python did not have to be mindful of keeping old
> code chugging along...

It is possible that someone proposed removing re.match for 3.0, but I do 
not remember any such discussion. Some things were dropped when that 
contraint was (teporarily) dropped.

tjr



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 23:51:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 00:51:07 -0300
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>
	<4A527F85.7030400@mrabarnett.plus.com>
Message-ID: <op.uwn8nnvnx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 19:49:41 -0300, MRAB <python at mrabarnett.plus.com>
escribi?:
> Chris Rebert wrote:

>>  from collections import defaultdict
>>  counts = defaultdict(lambda: 0)
>>
> Better is:
> counts = defaultdict(int)

For speed? This is even faster:
zerogen = itertools.repeat(0).next
counts = defaultdict(zerogen)

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 23:51:09 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 00:51:09 -0300
Subject: How to map size_t using ctypes?
References: <mailman.2691.1246888326.8015.python-list@python.org>
	<7belo1F21fs3vU1@mid.uni-berlin.de>
	<DB4ED723-C8DD-492F-A7CC-B3CE14F8B723@semanchuk.com>
Message-ID: <op.uwn9hrmpx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 13:29:21 -0300, Philip Semanchuk
<philip at semanchuk.com> escribi?:
> On Jul 6, 2009, at 12:10 PM, Diez B. Roggisch wrote:
>> Philip Semanchuk wrote:
>>
>>> I can't figure out how to map a C variable of size_t via Python's
>>> ctypes module.
>>
>> from ctypes import c_size_t
>
> D'oh! [slaps forehead]
>
> That will teach me to RTFM. [...] You'd be surprised at the amount of  
> Googling I did without learning this on my own.

Yep, seems like these terms in particular are hard to find. Searching for
+ctypes +size_t, the first "good" result comes only at page 3. Bad luck...
:(

-- 
Gabriel Genellina



From aahz at pythoncraft.com  Tue Jul  7 00:02:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 6 Jul 2009 21:02:19 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <h2uhcb$blq$1@panix3.panix.com>

In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>,
Steven D'Aprano  <steve at REMOVE-THIS-cybersource.com.au> wrote:
>On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>> kj wrote:
>>>
>>>     sense = cmp(func(hi), func(lo))
>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>
>> As already said before, unlike other languages, sense in english does
>> **not** mean direction. You should rewrite this part using a better
>> name. Wrong informations are far worse than no information at all.
>
>Absolutely.
>
>From Webster's Dictionary:
>
>      8. (Geom.) One of two opposite directions in which a line,
>      surface, or volume, may be supposed to be described by the
>      motion of a point, line, or surface.
>      [1913 Webster]
>
>
>And from WordNet:
>
>     2: the meaning of a word or expression; the way in which a word
>        or expression or situation can be interpreted
>
>Both meanings are relevant to the way KJ is using the word. Please take 
>your own advice and stop giving wrong information. As a native English 
>speaker, I had no difficulty understanding the meaning of "sense" in the 
>sense intended by KJ.

As another native English speaker, I agree with Jean-Michel; this is the
first time I've seen "sense" used to mean direction.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From mail at timgolden.me.uk  Tue Jul  7 00:11:30 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Tue, 07 Jul 2009 05:11:30 +0100
Subject: copytree with timeout in windows
In-Reply-To: <4A52B9D0.9040608@al.com.au>
References: <4A52B9D0.9040608@al.com.au>
Message-ID: <4A52CAF2.7010707@timgolden.me.uk>

Astan Chee wrote:
> Hi,
> I'm trying to modify the copytree function in shutil so that any file 
> being copied does not take more than 5 minutes (if it does, skip to the 
> next one). 

One suggestion is to use the CopyFileEx API
exposed in the win32file module from pywin32. That
allows for a callback function which can abort
the copy (or issue a progress meter, etc.).

Obviously, you'd have to roll your own copytree, but
that's not beyond the wit of man.

TJG


From me at haolian.org  Tue Jul  7 00:38:10 2009
From: me at haolian.org (Hao Lian)
Date: Tue, 07 Jul 2009 00:38:10 -0400
Subject: a little wsgi framework
In-Reply-To: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
References: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
Message-ID: <6a368$4a52d120$a652c80b$16349@ALLTEL.NET>

timmyt wrote:
> i'm interested in getting opinions on a small wsgi framework i
> assembled from webob, sqlalchemy, genshi, and various code fragments i
> found on the inter-tubes
> 
> here is the interesting glue - any comments / suggestions would be
> much appreciated

Fun! Since you're already using WebOb, you should
give webob.Response a try, which will handle your
headers in a sexier way. (If you start using
paste.httpexceptions and the middleware, you can
avoid manually sending headers altogether.)

http://pythonpaste.org/webob/reference.html#response-as-a-wsgi-application
http://pythonpaste.org/modules/httpexceptions.html#paste.httpexceptions.HTTPExceptionHandler

timmyt wrote:
>             global config
> 
>             try:
>                 return_dict = target(request, start_response)
>                 return_string = template.generate(**return_dict).render
> (method)
>                 config['database.Session'].commit()
>             except:
>                 config['database.Session'].rollback()
>                 raise
>             finally:
>                 config['database.Session'].remove()

The config global probably isn't thread-safe
depending on what you're doing with the
application. A safer way to go would be use Paste
Registry like Pylons does with its globals or just
attach it to Request.

http://pythonpaste.org/webob/reference.html#ad-hoc-attributes



From lie.1296 at gmail.com  Tue Jul  7 00:51:51 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 04:51:51 GMT
Subject: A Bug By Any Other Name ...
In-Reply-To: <mailman.2677.1246869173.8015.python-list@python.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com>	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>	<mailman.2674.1246866966.8015.python-list@python.org>	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
Message-ID: <HvA4m.3141$ze1.109@news-server.bigpond.net.au>

Chris Rebert wrote:
> On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
> D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
>> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim Golden
>> wrote:
>>
>>> The difficulty here is knowing where to put such a warning.
>>> You obviously can't put it against the "++" operator as such
>>> because... there isn't one.
>> This bug is an epiphenomenon. :)
> 
> Well, like I suggested, it /could/ be made an operator (or rather, a
> lexer token) which just causes a compile/parse error.
> 
> Cheers,
> Chris

There are edge cases (level: very rare) where you legitimately want to
actually do that, e.g.:

class A(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return B(self)
    def __neg__(self):
        return D(self)

class B(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return C(self)
    def __neg__(self):
        return A(self)

class C(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return D(self)
    def __neg__(self):
        return B(self)

class D(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return A(self)
    def __neg__(self):
        return C(self)

def cons(val):
    class E(object):
        value = val
    return E()

>>> a = A(cons(10))
>>> +a
<__main__.B object at 0x7fbf723c8690>
>>> ++a
<__main__.C object at 0x7fbf723c8710>
>>> +++a
<__main__.D object at 0x7fbf723c8710>
>>> --a
<__main__.C object at 0x7fbf723c8710>


From fetchinson at googlemail.com  Tue Jul  7 00:52:40 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Mon, 6 Jul 2009 21:52:40 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2ujrs$4c0$1@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
Message-ID: <fbe2e2100907062152u62d84480k63e6e41206df8fce@mail.gmail.com>

>> Yes, there are plenty of languages other than Java and C, but the
>> influence of C is admittedly huge in Python. Why do you think loops
>> are called "for", conditionals "if" or "while", functions return via
>> "return", loops terminate via "break" and keep going via "continue"
>> and why is comparison written as "==", etc, etc? All of these are
>> coming from C (or an even earlier language) and my point is that users
>
> 	for, if, and return were common keywords in FORTRAN.
>
> 	Not to mention BASIC
>
> 	Both of which predate C

Yes, hence my comment above, ".... coming from C (or an even earlier
language) ......".

Cheers,
Daniel


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:05:12 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:05:12 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
Message-ID: <006eb26f$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 21:02:19 -0700, Aahz wrote:

> In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>, Steven D'Aprano 
> <steve at REMOVE-THIS-cybersource.com.au> wrote:
>>On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>>> kj wrote:
>>>>
>>>>     sense = cmp(func(hi), func(lo))
>>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>>
>>> As already said before, unlike other languages, sense in english does
>>> **not** mean direction. You should rewrite this part using a better
>>> name. Wrong informations are far worse than no information at all.
>>
>>Absolutely.
>>
>>From Webster's Dictionary:
>>
>>      8. (Geom.) One of two opposite directions in which a line,
>>      surface, or volume, may be supposed to be described by the motion
>>      of a point, line, or surface.
>>      [1913 Webster]
>>
>>
>>And from WordNet:
>>
>>     2: the meaning of a word or expression; the way in which a word
>>        or expression or situation can be interpreted
>>
>>Both meanings are relevant to the way KJ is using the word. Please take
>>your own advice and stop giving wrong information. As a native English
>>speaker, I had no difficulty understanding the meaning of "sense" in the
>>sense intended by KJ.
> 
> As another native English speaker, I agree with Jean-Michel; this is the
> first time I've seen "sense" used to mean direction.


Just goes to show you learn something new all the time.

http://www.merriam-webster.com/dictionary/sense

    7: one of two opposite directions especially of motion (as 
    of a point, line, or surface)


http://dictionary.reference.com/browse/sense

    18.  Mathematics. one of two opposite directions in which 
    a vector may point.



Paraphrasing the Collins Dictionary of Mathematics:

The sense of a vector is the sign of the measure, contrasted with the 
magnitude. Thus the vectors AB and BA have the same direction but 
opposite sense. Sense is also used to distinguish clockwise and anti-
clockwise.

Sense is, if you like, a "signed direction". "Towards north" (say) as 
opposed to "along the north-south axis".



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:07:08 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:07:08 GMT
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <006eb2e3$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 15:02:26 -0700, Michael Mossey wrote:

> On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>>
>> > What is required in a python program to make sure it catches a
>> > control-
>> > c on the command-line? Do some i/o? The OS here is Linux.
>>
>> You can use a try/except to catch a KeyboardInterrupt exception, or you
>> can trap it using the signal
>> module:http://docs.python.org/library/signal.html
>>
>> You want to trap SIGINT.
>>
>> HTH
>> Philip
> 
> Thanks to both of you. However, my question is also about whether I need
> to be doing i/o or some similar operation for my program to notice in
> any shape or form that Control-C has been pressed. In the past, I've
> written Python programs that go about their business ignoring Ctrl-C.

I bet that somewhere in your code you have something like:


for x in really_big_list:
    try:
        long_running_process(x)
    except:
        continue


If that's what you're doing, stop! The correct way is:


for x in really_big_list:
    try:
        long_running_process(x)
    except Exception:
        # Let KeyboardInterrupt and SystemExit through.
        continue


or even:

for x in really_big_list:
    try:
        long_running_process(x)
    except (KeyboardInterrupt, SystemExit):
        print "User requested exit... shutting down now"
        cleanup()
        raise
    except Exception:
        continue



-- 
Steven


From lie.1296 at gmail.com  Tue Jul  7 01:13:28 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 05:13:28 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2uhcb$blq$1@panix3.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
Message-ID: <YPA4m.3147$ze1.970@news-server.bigpond.net.au>

Aahz wrote:
> In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>,
> Steven D'Aprano  <steve at REMOVE-THIS-cybersource.com.au> wrote:
>> On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>>> kj wrote:
>>>>     sense = cmp(func(hi), func(lo))
>>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>> As already said before, unlike other languages, sense in english does
>>> **not** mean direction. You should rewrite this part using a better
>>> name. Wrong informations are far worse than no information at all.
>> Absolutely.
>>
>>From Webster's Dictionary:
>>      8. (Geom.) One of two opposite directions in which a line,
>>      surface, or volume, may be supposed to be described by the
>>      motion of a point, line, or surface.
>>      [1913 Webster]
>>
>>
>> And from WordNet:
>>
>>     2: the meaning of a word or expression; the way in which a word
>>        or expression or situation can be interpreted
>>
>> Both meanings are relevant to the way KJ is using the word. Please take 
>> your own advice and stop giving wrong information. As a native English 
>> speaker, I had no difficulty understanding the meaning of "sense" in the 
>> sense intended by KJ.
> 
> As another native English speaker, I agree with Jean-Michel; this is the
> first time I've seen "sense" used to mean direction.

When people are fighting over things like `sense`, although sense may
not be strictly wrong dictionary-wise, it smells of something burning...


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:13:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:13:30 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
Message-ID: <006eb461$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 04:51:51 +0000, Lie Ryan wrote:

> Chris Rebert wrote:
>> On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
>> D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
>>> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim
>>> Golden wrote:
>>>
>>>> The difficulty here is knowing where to put such a warning. You
>>>> obviously can't put it against the "++" operator as such because...
>>>> there isn't one.
>>> This bug is an epiphenomenon. :)
>> 
>> Well, like I suggested, it /could/ be made an operator (or rather, a
>> lexer token) which just causes a compile/parse error.
>> 
>> Cheers,
>> Chris
> 
> There are edge cases (level: very rare) where you legitimately want to
> actually do that, e.g.:

Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.


Help on method __pos__ in module decimal:

__pos__(self, context=None) unbound decimal.Decimal method
    Returns a copy, unless it is a sNaN.

    Rounds the number (if more then precision digits)



-- 
Steven


From casevh at gmail.com  Tue Jul  7 01:16:39 2009
From: casevh at gmail.com (casevh)
Date: Mon, 6 Jul 2009 22:16:39 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org>
Message-ID: <c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com>

I discovered a serious bug with comparisons and have posted alpha2
which fixes that bug and adds Unicode support for Python 2.x

casevh


From clp2 at rebertia.com  Tue Jul  7 01:18:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 22:18:20 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <006eb461$0$9711$c3e8da3@news.astraweb.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
	<006eb461$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <50697b2c0907062218t34c011ecna831de8aa441d8e1@mail.gmail.com>

On Mon, Jul 6, 2009 at 10:13 PM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Tue, 07 Jul 2009 04:51:51 +0000, Lie Ryan wrote:
>
>> Chris Rebert wrote:
>>> On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
>>> D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
>>>> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim
>>>> Golden wrote:
>>>>
>>>>> The difficulty here is knowing where to put such a warning. You
>>>>> obviously can't put it against the "++" operator as such because...
>>>>> there isn't one.
>>>> This bug is an epiphenomenon. :)
>>>
>>> Well, like I suggested, it /could/ be made an operator (or rather, a
>>> lexer token) which just causes a compile/parse error.
>>>
>>> Cheers,
>>> Chris
>>
>> There are edge cases (level: very rare) where you legitimately want to
>> actually do that, e.g.:
>
> Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.
>
>
> Help on method __pos__ in module decimal:
>
> __pos__(self, context=None) unbound decimal.Decimal method
> ? ?Returns a copy, unless it is a sNaN.
>
> ? ?Rounds the number (if more then precision digits)

Well, yes, but when would you apply it twice in a row?

(Not that I strongly support the prohibition idea, just thought it
should be brought up)

Cheers,
Chris
-- 
http://blog.rebertia.com


From mensanator at aol.com  Tue Jul  7 01:47:21 2009
From: mensanator at aol.com (Mensanator)
Date: Mon, 6 Jul 2009 22:47:21 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com>
Message-ID: <fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com>

On Jul 7, 12:16?am, casevh <cas... at gmail.com> wrote:
> I discovered a serious bug with comparisons and have posted alpha2
> which fixes that bug and adds Unicode support for Python 2.x
>
> casevh

Damn! I was just congatulating myself for pulling off
a hat trick (there had been no point in downloading
3.x without gmpy so I have been putting it off):

- installing Python 3.1
- installing gmpy 1.10
- converting my Collatz Function library to 3.1 syntax

And it all worked smoothly, just had to add parentheses
to my print statements, change xrange to range and all
my / to // (the library is exclusively integer). I had
gmpy running in my library on 3.1 in about 10 minutes.

So I'll have to re-do the gmpy install. Shouldn't be
any big deal.

I started doing some real world tests. Generally, things
look good (nothing crashes, timing looks not bad) but
I'm getting some funny results on one of my tests, so
I'll report back when I have more information.


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:57:14 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:57:14 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
Message-ID: <006ebea2$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:

> When people are fighting over things like `sense`, although sense may
> not be strictly wrong dictionary-wise, it smells of something burning...

That would be my patience.

I can't believe the direction this discussion has taken. Anybody sensible 
would be saying "Oh wow, I've just learned a new meaning to the word, 
that's great, I'm now less ignorant than I was a minute ago". But oh no, 
we mustn't use a standard meaning to a word, heaven forbid we disturb 
people's ignorance by teaching them something new.

It's as simple as this: using `sense` as a variable name to record the 
sense of a function is not a code smell, any more than using `flag` to 
record a flag would be, or `sign` to record the sign of an object. If you 
don't know the appropriate meanings of the words sense, flag or sign, 
learn them, don't dumb down my language.


-- 
Steven


From nomail at thank.you  Tue Jul  7 02:01:39 2009
From: nomail at thank.you (jack catcher (nick))
Date: Tue, 07 Jul 2009 09:01:39 +0300
Subject: Python and webcam capture delay?
In-Reply-To: <pan.2009.07.06.19.41.52.828000@nowhere.com>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
Message-ID: <6xB4m.21104$vi5.8567@uutiset.elisa.fi>

Nobody kirjoitti:
> On Mon, 06 Jul 2009 20:41:03 +0300, jack catcher (nick) wrote:
> 
>>> Does the webcam just deliver frames, or are you getting frames out of
>>> a decoder layer?  If it's the latter, you want to distribute the encoded
>>> video, which should be much lower bandwidth.  Exactly how you do that
>>> depends a bit on what format the webcam claims to deliver.
>> Well, getting already encoded video from the webcam sounds almost like a 
>> free lunch (which it probably is not). At least I wouldn't want to get 
>> too long a delay because of the encoding.
>>
>> I haven't got the webcam(s) yet, and I guess I can basically purchase 
>> any ones I find suitable for getting the job done. Any recommendations?
> 
> The webcam is bound to do some encoding; most of them use USB "full speed"
> (12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.
> 
> Chroma subsampling and JPEG compression will both reduce the bandwidth
> without introducing noticable latency (the compression time will be no
> more than one frame).
> 
> Temporal compression will reduce the bandwidth further. Using B-frames
> (frames which contain the differences from a predicted frame which is
> based upon both previous and subsequent frames) will provide more 
> compression, but increases the latency significantly. For this reason, the
> compression built into video cameras normally only uses P-frames (frames
> which contain the differences from a predicted frame which is based only
> upon previous frames).
> 
> The biggest issue is likely to be finding latency specifications, followed
> by finding a camera which meets your latency requirement.

Thanks for the comments. Unfortunately, such specifications aren't easy 
to find, even in reviews. Fortunately several newer webcams seem at 
least to use usb2.

Regarding Python, I'll have to check whether the ImageCapture extension 
works at all, as someone suggested earlier, and the possibility of using 
DirectShow. I'm still considering Matlab as an option for Python here.


From ptmcg at austin.rr.com  Tue Jul  7 02:02:44 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Mon, 6 Jul 2009 23:02:44 -0700 (PDT)
Subject: parsing times like "5 minutes ago"?
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
Message-ID: <90911ef7-ff17-4aa0-9816-4579a638db92@j32g2000yqh.googlegroups.com>

On Jul 6, 7:21?pm, m... at pixar.com wrote:
> I'm looking for something like Tcl's [clock scan] command which parses
> human-readable time strings such as:
>
> ? ? % clock scan "5 minutes ago"
> ? ? 1246925569
> ? ? % clock scan "tomorrow 12:00"
> ? ? 1246993200
> ? ? % clock scan "today + 1 fortnight"
> ? ? 1248135628
>
> Does any such package exist for Python?
>
> Many TIA!
> Mark
>
> --
> Mark Harrison
> Pixar Animation Studios

I've been dabbling with such a parser with pyparsing - here is my
progress so far: http://pyparsing.wikispaces.com/UnderDevelopment

It parses these test cases:

today
tomorrow
yesterday
in a couple of days
a couple of days from now
a couple of days from today
in a day
3 days ago
3 days from now
a day ago
now
10 minutes ago
10 minutes from now
in 10 minutes
in a minute
in a couple of minutes
20 seconds ago
in 30 seconds
20 seconds before noon
20 seconds before noon tomorrow
noon
midnight
noon tomorrow


-- Paul


From wsysdu at gmail.com  Tue Jul  7 02:06:13 2009
From: wsysdu at gmail.com (Eric Wong)
Date: Tue, 07 Jul 2009 14:06:13 +0800
Subject: why PyObject_VAR_HEAD?
References: <d9c79d1e-3c30-44c5-8c1b-2378b3239b53@t21g2000yqi.googlegroups.com>
Message-ID: <h2uol6$eep$1@aioe.org>

kio wrote:

> Hi,
> 
> I'm studying the CPython source code. I don?t quite understand why
> they?re using PyObject_VAR_HEAD to define struct like PyListObject. 
To
> define such kind of struct, could I use _PyObject_HEAD_EXTRA as a
> header and add "items" pointer and "allocated" count explicity? Is
> there any difference?
> 
> Thanks.
> 
> Eric

first, _PyObject_HEAD_EXTRA is only useful for debug and defined as:
#ifdef Py_TRACE_REFS
   #define _PyObject_HEAD_EXTRA 	\
      struct _object *_ob_next;   \
      struct _object *_ob_prev;
   #define _PyObject_EXTRA_INIT 0, 0,
#else 
   #define _PyObject_HEAD_EXTRA
   #define _PyObject_EXTRA_INIT
#endif

and PyObject_HEAD is defined as
#define PyObject_HEAD    \
   _PyObject_HEAD_EXTRA  \
   int ob_refcnt;        \
   struct _typeobject *ob_type;

PyObject_VAR_HEAD defined as
#define PyObject_VAR_HEAD   \
   PyObject_HEAD            \
   int ob_size;

so you can see the differences between them here.
PyListObject is defined as
typedef struct{
    PyObject_VAR_HEAD
    PyObject **ob_item;
    int allocated;
}PyListObject;

After unfolding these macros we can get
typedef struct{
    _PyObject_HEAD_EXTRA
    int ob_refcnt;
    struct _typeobject *ob_type;
    int ob_size;
    PyObject **ob_item;
    int allocated;
}PyListObject;

So, if we don't use macros, we have to specify not only the "item" and 
"allocated", but also the ref count and type information of the object 
and the size info for a variable object. These information is not only 
used by PyListObject, but also PyStringObject and PyDictObject, so 
macros make it convenient and consize. 




From rogerb at rogerbinns.com  Tue Jul  7 02:16:10 2009
From: rogerb at rogerbinns.com (Roger Binns)
Date: Mon, 06 Jul 2009 23:16:10 -0700
Subject: Opening a SQLite database in readonly mode
In-Reply-To: <h2tnpp$6if$1@ger.gmane.org>
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org>
Message-ID: <h2up7a$epu$1@ger.gmane.org>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Joshua Kugler wrote:
> BTW, APSW is written by the same author as pysqlite.

Not even remotely true :-)  pysqlite was written by various people, with
the maintainer of the last several years being Gerhard H?ring.  I am the
(sole) author of APSW and have not contributed any code to pysqlite
although ideas have flowed freely between the projects and we share a
mailing list.

I started APSW in late 2004 because I wanted to use SQLite from Python
rather than using a layer that pretended SQLite was like other
databases.  There were various quirks of pysqlite I also didn't like
(many since corrected) and so scratched my itch.

If you are just doing simple queries then there isn't much apparent
difference.  If you want to be a "power user" of SQLite then APSW is for
you.  SQLite has many cool features such as virtual tables (you provide
the underlying data for the SQL queries to work on) and VFS (you provide
the file access).  See this link for more details:

  http://apsw.googlecode.com/svn/publish/pysqlite.html

Roger
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkpS6CUACgkQmOOfHg372QS0/gCgiHD9ukUlQYJGCIMWb9hNMLCM
Y/cAnid4dAeFHIdLBmKzGsXrvANkvhR5
=U0wg
-----END PGP SIGNATURE-----



From nagle at animats.com  Tue Jul  7 02:21:02 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 06 Jul 2009 23:21:02 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <0260603f$0$20657$c3e8da3@news.astraweb.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<7xvdm8thpo.fsf@ruckus.brouhaha.com>	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>	<7xfxdcqabg.fsf@ruckus.brouhaha.com>	<4a501a5e$0$1640$742ec2ed@news.sonic.net>	<0260559c$0$20657$c3e8da3@news.astraweb.com>	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <4a52e8ef$0$1633$742ec2ed@news.sonic.net>

Steven D'Aprano wrote:
> On Sun, 05 Jul 2009 01:58:13 -0700, Paul Rubin wrote:
> 
>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>>> Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't
>>> see how a case statement would help you here: you're not dispatching on
>>> a value, but running through a series of tests until one passes.
>> A case statement switch(x):... into a bunch of constant case labels
>> would be able to use x as an index into a jump vector, and/or do an
>> unrolled logarithmic (bisection-like) search through the tests, instead
>> of a linear search.
> 
> Yes, I'm aware of that, but that's not what John's code is doing -- he's 
> doing a series of if expr ... elif expr tests. I don't think a case 
> statement can do much to optimize that.

    (I didn't write that code; it's from "http://code.google.com/p/html5lib/",
which is a general purpose HTML 5 parser written in Python.  It's compatible
with ElementTree and/or BeautifulSoup.  I currently use a modified
BeautifulSoup for parsing real-world HTML in a small-scale crawler, and
I'm looking at this as an HTML 5 compatible replacement.)

					John Nagle


From nagle at animats.com  Tue Jul  7 02:31:26 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 06 Jul 2009 23:31:26 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <02605ef2$0$20657$c3e8da3@news.astraweb.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <4a52eb5f$0$1663$742ec2ed@news.sonic.net>

Steven D'Aprano wrote:
> On Sun, 05 Jul 2009 10:12:54 +0200, Hendrik van Rooyen wrote:
> 
>> Python is not C.
> 
> John Nagle is an old hand at Python. He's perfectly aware of this, and 
> I'm sure he's not trying to program C in Python.
> 
> I'm not entirely sure *what* he is doing, and hopefully he'll speak up 
> and say, but whatever the problem is it's not going to be as simple as 
> that.

     I didn't write this code; I'm just using it.  As I said in the
original posting, it's from "http://code.google.com/p/html5lib".
It's from an effort to write a clean HTML 5 parser in Python for
general-purpose use.  HTML 5 parsing is well-defined for the awful
cases that make older browsers incompatible, but quite complicated.
The Python implementation here is intended partly as a reference
implementation, so browser writers have something to compare with.

     I have a small web crawler robust enough to parse
real-world HTML, which can be appallingly bad.  I currently use
an extra-robust version of BeautifulSoup, and even that sometimes
blows up.  So I'm very interested in a new Python parser which supposedly
handles bad HTML in the same way browsers do.  But if it's slower
than BeautifulSoup, there's a problem.

					John Nagle


From __peter__ at web.de  Tue Jul  7 02:33:48 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 07 Jul 2009 08:33:48 +0200
Subject: module name versus function name resolution conflict.
References: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
Message-ID: <h2uq7c$lq0$01$1@news.t-online.com>

rocky wrote:

> Someone recently reported a problem in pydb where a function defined
> in his program was conflicting with a module name that pydb uses. I
> think I understand what's wrong, but I don't have any elegant
> solutions to the problem. Suggestions would be appreciated.
> 
> In a nutshell, here's the problem:
> 
> In file fns:
> 
>   def foo(): print "foo"
> 
> In file pdebug.py:
> 
>   import fns, sys
> 
>   def trace_dispatch(frame, event, arg):
>       fns.foo()
>       print frame, event, arg
>       return trace_dispatch
> 
>   sys.settrace(trace_dispatch)
>   execfile('myprogram.py')
> 
> Finally file myprogram.py:
> 
>   def fns(): print "This is the *other* fns"
> 
> When you run pdebug.py you get:
> 
> $ python pdebug.py
> foo
> <frame object at 0xdd9030> call None
> foo
> <frame object at 0xdd9030> line None
> Traceback (most recent call last):
>   File "pdebug.py", line 7, in <module>
>     execfile('myprogram.py')
>   File "myprogram.py", line 1, in <module>
>     def fns(): print "This is the *other* fns"
>   File "pdebug.py", line 3, in trace_dispatch
>     fns.foo()
> AttributeError: 'function' object has no attribute 'foo'
> 
> 
> Basically inside the trace hook, local functions are visible and take
> precedence over (global) module names. I could move "import fns"
> inside trace_dispatch(), but I'd have to do that in all of the methods
> that module "fns" is used.  Also note that using the form:
>   from fns import foo
> 
> would eliminate the conflict on "fns", but I'd still have potential
> conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> reduce the chance of a conflict but not eliminate it.
> 
> Suggestions?

Can you run the program in another namespace?

execfile("myprogram.py", {"__name__":"__main__"})

Alternatively move trace_dispatch into yet another module and import it into 
pdebug.

from elsewhere import trace_dispatch

Peter




From wsysdu at gmail.com  Tue Jul  7 02:56:40 2009
From: wsysdu at gmail.com (Eric Wong)
Date: Tue, 07 Jul 2009 14:56:40 +0800
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com>
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com>
	<173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com>
Message-ID: <h2urjo$h4d$1@aioe.org>

Pedram wrote:

> Hello Mr. Dickinson. Glad to see you again :)
> 
> On Jul 6, 5:46 pm, Mark Dickinson <dicki... at gmail.com> wrote:
>> On Jul 6, 1:24 pm, Pedram <pm567... at gmail.com> wrote:
>>
>> > OK, fine, I read longobject.c at last! :)
>> > I found that longobject is a structure like this:
>>
>> > struct _longobject {
>> > struct _object *_ob_next;
>> > struct _object *_ob_prev;
>>
>> For current CPython, these two fields are only present in debug
>> builds;  for a normal build they won't exist.
> 
> I couldn't understand the difference between them. What are debug
> build and normal build themselves? And You mean in debug build
> PyLongObject is a doubly-linked-list but in normal build it is just 
an
> array (Or if not how it'll store in this mode)?
> 
we use the macro Py_TRACE_REFS to differ the code for debug build and 
normal build, that's to say, in debug build and normal build the codes 
are actually *different*. In debug build, not only PyLongObject but 
all Objects are linked by a doubly-linked-list and it can make the 
debug process less painful. But in normal build, objects are 
seperated! After an object is created, it will never be moved, so we 
can and should refer to an object only by it's address(pointer). 
There's no one-big-container like a list or an array for objects.



From astan.chee at al.com.au  Tue Jul  7 02:56:55 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 7 Jul 2009 16:56:55 +1000
Subject: copytree with timeout in windows
In-Reply-To: <4A52CAF2.7010707@timgolden.me.uk>
References: <4A52B9D0.9040608@al.com.au> <4A52CAF2.7010707@timgolden.me.uk>
Message-ID: <4A52F1B7.2070507@al.com.au>

Tim Golden wrote:
> Astan Chee wrote:
>   
>> Hi,
>> I'm trying to modify the copytree function in shutil so that any file 
>> being copied does not take more than 5 minutes (if it does, skip to the 
>> next one). 
>>     
>
> One suggestion is to use the CopyFileEx API
> exposed in the win32file module from pywin32. That
> allows for a callback function which can abort
> the copy (or issue a progress meter, etc.).
>   
Thanks, but looking in the documentation there is no callback function. 
Did you mean */the Progress Routine?
Thanks again
/*
> Obviously, you'd have to roll your own copytree, but
> that's not beyond the wit of man.
>
> TJG
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/adb98be6/attachment.html>

From http  Tue Jul  7 03:38:50 2009
From: http (Paul Rubin)
Date: 07 Jul 2009 00:38:50 -0700
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
References: <mailman.2741.1246929917.8015.python-list@python.org>
Message-ID: <7x3a99gcxh.fsf@ruckus.brouhaha.com>

palewire <ben.welsh at gmail.com> writes:
> In my application, I'd like to have a function that compares two values,
> either of which may be null, and then classify the result depending on
> whether one is higher or lower than the other.

Didn't we just have a huge thread about that?  Using a special null
value is often (not always) a code smell.  But anyway (untested):

    def compare(a,b):
       if a is None and b is None:  # I'm guessing you meant this
           return "No data"
       if a == b:
           return "Stayed the same" if a != 0 else "Never had"
       elif a < b:
           return "gained"
       else:
           # we know here that a > b
           return "Lost some" if b > 0 else "Lost all"

I don't know what you intended to do in the case where exactly one of
(a,b) is None, so I'll leave that to you.


From mail at timgolden.me.uk  Tue Jul  7 03:42:55 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Tue, 07 Jul 2009 08:42:55 +0100
Subject: copytree with timeout in windows
In-Reply-To: <4A52F1B7.2070507@al.com.au>
References: <4A52B9D0.9040608@al.com.au> <4A52CAF2.7010707@timgolden.me.uk>
	<4A52F1B7.2070507@al.com.au>
Message-ID: <4A52FC7F.8050308@timgolden.me.uk>

Astan Chee wrote:
> Tim Golden wrote:
>> Astan Chee wrote:
>>  
>>> Hi,
>>> I'm trying to modify the copytree function in shutil so that any file 
>>> being copied does not take more than 5 minutes (if it does, skip to 
>>> the next one).     
>>
>> One suggestion is to use the CopyFileEx API
>> exposed in the win32file module from pywin32. That
>> allows for a callback function which can abort
>> the copy (or issue a progress meter, etc.).
>>   
> Thanks, but looking in the documentation there is no callback function. 
> Did you mean */the Progress Routine?


Well, depending on which hairs you're splitting, I would
argue that the Progress Routine *is* a callback function:
it is a function which is called back. But, yes, I
did mean that. :)

TJG


From piet at cs.uu.nl  Tue Jul  7 04:01:40 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 10:01:40 +0200
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2724.1246918979.8015.python-list@python.org>
	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
Message-ID: <m2y6r0diqj.fsf@cs.uu.nl>

>>>>> Nile <nile_mcadams at yahoo.com> (N) wrote:

>N> I initialized the dictionary earlier in the program like this -

>N>   hashtable = {}

>N> I changed the "dict" to hashtable but I still get the same result
>N> I will try to learn about the defaultdict but I'm just trying to keep
>N> it as simple as I can for now

>N> Revised code

>N> for x in range(len(file_list)):
>N> 	d = open(file_list[x] , "r")
>N> 	data = d.readlines()
>N> 	k = 0
>N> 	k = above_or_below(data)
>N> 	print "here is the value that was returned ",k
>N> 	hashtable[k] = hashtable.get(k,0) + 1


>N> hashtable_list = hashtable.values()
>N> print "here is a list of the dictionary values ", hashtable_list
>N> print "the length of the dictionary is ", len(hashtable)

>N> Output
>N> # The first 3 lines are printed from the function
>N> # right before the return statement.  This output
>N> # snippet shows the last two stocks.  The function
>N> # SAYS it is returning the correct value but only
>N> # the last date seems to make it to the hashtable
>N> Function will return k which = 11/11/2008
>N> Function will return k which = 11/12/2008
>N> Function will return k which = 11/14/2008

>N> # this line is printed from the code above
>N> # I don't understand why all three dates don't
>N> # seem to make it to the main program.  Only
>N> # the last date seems to be recognized
>N> here is the value that was returned 11/14/2008

>N> Function will return k which = 11/11/2008
>N> Function will return k which = 11/12/2008
>N> Function will return k which = 11/14/2008
>N> here is the value that was returned 11/14/2008
>N> here is a list of the dictionary values [5]
>N> the length of the dictionary is 1
>>> Exit code: 0

Now in your code there is a 1-1 relation between printing 
"here is the value that was returned" and incrementing the hashtable
entry. In your log there are only 2 prints of "here is the value that
was returned" so how can the count be 5? Are you hiding something from
us? 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From chris at simplistix.co.uk  Tue Jul  7 04:06:49 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 09:06:49 +0100
Subject: Where does setuptools live?
In-Reply-To: <d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
Message-ID: <4A530219.6040007@simplistix.co.uk>

David Lyon wrote:
> setuptools... as far as I can see isn't actually installed until you
> install easyinstall...

That depends... I exclusively use buildout to manage my python packages, 
and sadly that relies on setuptools...

> Pip (http://pypi.python.org/pypi/pip) and enstall 
> (http://pypi.python.org/pypi/Enstaller/3.1.0) seem to be forks of 
> setuptools already...
> 
> So it looks like it's already been forked to some degree..
> 
> What hasn't happened is enough testing of pypi packages and installing
> with setuptools/pip/enstall from pypi.

What needs testing?

More important for me is which of these has the most active development 
community. How do we judge that?

> If the xmlrpc links actually "worked" on pypi...

What about it doesn't work?

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From duncan.booth at invalid.invalid  Tue Jul  7 04:19:47 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 7 Jul 2009 08:19:47 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<mailman.2753.1246941897.8015.python-list@python.org>
Message-ID: <Xns9C4173416946Fduncanbooth@127.0.0.1>

Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:

> for, if, and return were common keywords in FORTRAN.

Really? What does 'for' do in FORTRAN?

P.S. Does FORTRAN actually have keywords these days? Back when I learned it 
there was no such thing as a reserved word though for all I know they may 
have since added them.

-- 
Duncan Booth http://kupuguy.blogspot.com


From afriere at yahoo.co.uk  Tue Jul  7 04:48:30 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Tue, 7 Jul 2009 01:48:30 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com> 
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com> 
	<h2uhcb$blq$1@panix3.panix.com>
	<006eb26f$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <e246b4fe-00bd-485c-a1bd-92df4762ad92@j9g2000prh.googlegroups.com>

On Jul 7, 3:05?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:

[snip]

> Sense is, if you like, a "signed direction".

Or to put it another way, in the graphical representation of a vector,
'direction' is the line, 'sense' is the arrowhead.


From stefan_ml at behnel.de  Tue Jul  7 05:09:59 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 11:09:59 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a52eb5f$0$1663$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
	<4a52eb5f$0$1663$742ec2ed@news.sonic.net>
Message-ID: <4a5310e7$0$31327$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
>     I have a small web crawler robust enough to parse
> real-world HTML, which can be appallingly bad.  I currently use
> an extra-robust version of BeautifulSoup, and even that sometimes
> blows up.  So I'm very interested in a new Python parser which supposedly
> handles bad HTML in the same way browsers do.  But if it's slower
> than BeautifulSoup, there's a problem.

Well, if performance matters in any way, you can always use lxml's
blazingly fast parser first, possibly trying a couple of different
configurations, and only if all fail, fall back to running html5lib over
the same input. That should give you a tremendous speed-up over your
current code in most cases, while keeping things robust in the hard cases.

Note the numbers that Ian Bicking has for HTML parser performance:

http://blog.ianbicking.org/2008/03/30/python-html-parser-performance/

You should be able to run lxml's parser ten times in different
configurations (e.g. different charset overrides) before it even reaches
the time that BeautifulSoup would need to parse a document once. Given that
undeclared character set detection is something where BS is a lot better
than lxml, you can also mix the best of both worlds and use BS's character
set detection to configure lxml's parser if you notice that the first
parsing attempts fail.

And yes, html5lib performs pretty badly in comparison (or did, at the
time). But the numbers seem to indicate that if you can drop the ratio of
documents that require a run of html5lib below 30% and use lxml's parser
for the rest, you will still be faster than with BeautifulSoup alone.

Stefan


From dickinsm at gmail.com  Tue Jul  7 05:10:31 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 7 Jul 2009 02:10:31 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com> 
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com> 
	<173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com>
Message-ID: <2169e268-3fa7-4320-bef0-2619b8d1d040@h8g2000yqm.googlegroups.com>

On Jul 6, 4:13?pm, Pedram <pm567... at gmail.com> wrote:
> On Jul 6, 5:46?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> > On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
>
> > > OK, fine, I read longobject.c at last! :)
> > > I found that longobject is a structure like this:
>
> > > struct _longobject {
> > > ? ? struct _object *_ob_next;
> > > ? ? struct _object *_ob_prev;
>
> > For current CPython, these two fields are only present in debug
> > builds; ?for a normal build they won't exist.
>
> I couldn't understand the difference between them. What are debug
> build and normal build themselves? And You mean in debug build
> PyLongObject is a doubly-linked-list but in normal build it is just an
> array (Or if not how it'll store in this mode)?

No:  a PyLongObject is stored the same way (ob_size giving sign and
number of digits, ob_digit giving the digits themselves) whether or
not a debug build is in use.

A debug build does various things (extra checks, extra information) to
make it easier to track down problems.  On Unix-like systems, you can
get a debug build by configuring with the --with-pydebug flag.

The _ob_next and _ob_prev fields have nothing particularly to do with
Python longs; for a debug build, these two fields are added to *all*
Python objects, and provide a doubly-linked list that links all 'live'
Python objects together.  I'm not really sure what, if anything, the
extra information is used for within Python---it might be used by some
external tools, I guess.

Have you looked at the C-API documentation?

http://docs.python.org/c-api/index.html

_ob_next and _ob_prev are described here:

http://docs.python.org/c-api/typeobj.html#_ob_next

(These docs are for Python 2.6;  I'm not sure what version you're
working with.)

Mark


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 05:19:46 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 11:19:46 +0200
Subject: a little wsgi framework
In-Reply-To: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
References: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
Message-ID: <4a53132c$0$10839$426a34cc@news.free.fr>

timmyt a ?crit :
> i'm interested in getting opinions on a small wsgi framework i
> assembled from webob, sqlalchemy, genshi, and various code fragments i
> found on the inter-tubes
> 
> here is the interesting glue - any comments / suggestions would be
> much appreciated

<meta>
Well... My first comment would be about the usefulness of yet another 
Python web framework, but let's not worry about this...
</meta>

> ------------------
> the wsgi app
> ------------------
> def application(environ, start_response):
>     path = environ.get('PATH_INFO', '').lstrip('/')
> 
>     for regex, callback in urls:
>         match = re.search(regex, path)


I don't know where these "urls" come from. But anyway : if they live in 
some sort of long-running process, you may want to precompile them.

>         if match:
>             environ['myapp.url_args'] = match.groups()
>             request = webob.Request(environ)
> 
>             try:
>                 return callback(request, start_response)
>             except Exception, ex:

How are redirect etc handled ?

>                 start_response('500 Internal Server Error', [('Content-
> Type', 'text/plain')])
>                 return [traceback.format_exc()]

A configuration option controlling the display of the traceback would be 
fine - I surely don't want the traceback being displayed to anyone when 
  the app goes into production.

Also, logging the error and traceback might be useful.


>     start_response('404 Not Found', [('Content-Type', 'text/plain')])
>     return ["Couldn't find the URL specified."]
> 

And in both cases, having the ability to use "custom" 500 and 404 pages 
might be nice too.


> ----------------------------------
> the controller decorator
> ----------------------------------
> def web_decorator(filename, method='html'):
 >
>     def decorator(target):

May I suggest some renaming here ?

filename => path (or 'template_path' ?)
method   => content_type
target   => controller or function or callback or....

>         def wrapper(request, start_response):
> 
>             #genshi TemplateLoader
>             template = loader.load(filename)
> 
>             global config

Probably not thread-safe....

>             try:
>                 return_dict = target(request, start_response)
>                 return_string = template.generate(**return_dict).render
> (method)


Renaming again:
return_dict => context
return_string => data or text or ???

>                 config['database.Session'].commit()
>             except:
>                 config['database.Session'].rollback()
>                 raise
>             finally:
>                 config['database.Session'].remove()

This doesn't leave much control on transactions... Sometimes you want to 
handle it manually one way or another.

>             #TODO: alter 'Content-Type' per method being passed
>             start_response('200 OK', [('Content-Type', 'text/html')])
>             return [return_string]

Ok, so here again, I don't understand how redirects can work. Also, if 
you do use start_response here, I don't get why you still pass it to the 
callback function.

>         return wrapper
> 
>     return decorator

slightly OT, but preserving infos on the decorated function might help 
too (introspection, debugging etc).


My 2 cents...


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 05:27:52 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 11:27:52 +0200
Subject: A Bug By Any Other Name ...
In-Reply-To: <mailman.2746.1246935242.8015.python-list@python.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
Message-ID: <4a531512$0$9355$426a74cc@news.free.fr>

Daniel Fetchinson a ?crit :
(snip)
> and my point is that users
> are most of time correct when they assume that something will work the
> same way as in C.

Oh, really ? They would surely be wrong if they'd expect the for loop to 
have any similarity with a C for loop, or - a *very* common error - if 
they'd expect assignment to work the same way as in C.

> So I'd think that putting a warning in a FAQ or a Python Gotchas list
> about ++n would be very useful for many users.

Might eventually be useful, but I can't hardly recall of more than a 
couple threads on this topic in 8+ years.



From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 05:29:10 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 11:29:10 +0200
Subject: A Bug By Any Other Name ...
In-Reply-To: <mailman.2754.1246945937.8015.python-list@python.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>	<h2ujrs$4c0$1@ger.gmane.org>
	<mailman.2754.1246945937.8015.python-list@python.org>
Message-ID: <4a531560$0$9355$426a74cc@news.free.fr>

Daniel Fetchinson a ?crit :
>>> Yes, there are plenty of languages other than Java and C, but the
>>> influence of C is admittedly huge in Python. Why do you think loops
>>> are called "for", conditionals "if" or "while", functions return via
>>> "return", loops terminate via "break" and keep going via "continue"
>>> and why is comparison written as "==", etc, etc? All of these are
>>> coming from C (or an even earlier language) and my point is that users
>> 	for, if, and return were common keywords in FORTRAN.
>>
>> 	Not to mention BASIC
>>
>> 	Both of which predate C
> 
> Yes, hence my comment above, ".... coming from C (or an even earlier
> language) ......".


Mmm... Should we then claim that "the influence of FORTRAN is admittedly 
huge in Python" ?-)



From rocky at gnu.org  Tue Jul  7 05:44:07 2009
From: rocky at gnu.org (rocky)
Date: Tue, 7 Jul 2009 02:44:07 -0700 (PDT)
Subject: module name versus function name resolution conflict.
References: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
	<h2uq7c$lq0$01$1@news.t-online.com>
Message-ID: <f22b8224-97fa-4296-b175-19bf19b21fd8@d32g2000yqh.googlegroups.com>

On Jul 7, 2:33?am, Peter Otten <__pete... at web.de> wrote:
> rocky wrote:
> > Someone recently reported a problem in pydb where a function defined
> > in his program was conflicting with amodulenamethat pydb uses. I
> > think I understand what's wrong, but I don't have any elegant
> > solutions to the problem. Suggestions would be appreciated.
>
> > In a nutshell, here's the problem:
>
> > In file fns:
>
> > ? def foo(): print "foo"
>
> > In file pdebug.py:
>
> > ? import fns, sys
>
> > ? def trace_dispatch(frame, event, arg):
> > ? ? ? fns.foo()
> > ? ? ? print frame, event, arg
> > ? ? ? return trace_dispatch
>
> > ? sys.settrace(trace_dispatch)
> > ? execfile('myprogram.py')
>
> > Finally file myprogram.py:
>
> > ? def fns(): print "This is the *other* fns"
>
> > When you run pdebug.py you get:
>
> > $ python pdebug.py
> > foo
> > <frame object at 0xdd9030> call None
> > foo
> > <frame object at 0xdd9030> line None
> > Traceback (most recent call last):
> > ? File "pdebug.py", line 7, in <module>
> > ? ? execfile('myprogram.py')
> > ? File "myprogram.py", line 1, in <module>
> > ? ? def fns(): print "This is the *other* fns"
> > ? File "pdebug.py", line 3, in trace_dispatch
> > ? ? fns.foo()
> > AttributeError: 'function' object has no attribute 'foo'
>
> > Basically inside the trace hook, local functions are visible and take
> > precedence over (global)modulenames.

I was sloppy here. The "local" is the wrong word as suggested by the
first remedy proposed.
"entry in the global namespace dictionary" is probably closer to the
truth.

> > I could move "import fns"
> > inside trace_dispatch(), but I'd have to do that in all of the methods
> > thatmodule"fns" is used. ?Also note that using the form:
> > ? from fns import foo
>
> > would eliminate the conflict on "fns", but I'd still have potential
> > conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> > reduce the chance of a conflict but not eliminate it.
>
> > Suggestions?
>
> Can you run the program in another namespace?
>
> execfile("myprogram.py", {"__name__":"__main__"})
>
> Alternatively move trace_dispatch into yet anothermoduleand import it into
> pdebug.
>
> from elsewhere import trace_dispatch
>
> Peter

Both of these work. Thanks! (I haven't figured out how to adapt it to
the messier context of the program yet). The second suggestion
interesting/weird:
by putting trace_dispatch in another module, compilation and name/
function resolution of fns.foo
is done before myprogram has a chance to redefine fns.



From lie.1296 at gmail.com  Tue Jul  7 06:08:14 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 10:08:14 GMT
Subject: Method to separate unit-test methods and data?
In-Reply-To: <mailman.2645.1246819693.8015.python-list@python.org>
References: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
	<mailman.2645.1246819693.8015.python-list@python.org>
Message-ID: <i8F4m.3224$ze1.1839@news-server.bigpond.net.au>

Nick Daly wrote:
> Hi,
> 
> I was wondering if it's possible / if there are any simple methods
> known of storing unit-test functions and their data in separate files?
> 
> Perhaps this is a strange request, but it does an excellent job of
> modularizing code.  As far as revision control goes, it makes it
> easier to discern between new or changed test cases, and changes in
> the test data.
> 
<snip>
> Does anyone have any solutions for these problems?  First, is there a
> known and simple way to separate unit-test data and methods into
> separate files?  Secondly, if not, is there a simple way to convert
> strings into other base types, like lists, dictionaries, and so forth?
> Or, am I going to have to write my own list-parsing methods?  Would
> pickling help?  I haven't yet had a chance to look into if or how that
> would work...  If there's anything else I can clarify about this
> request, feel free to let me know.
> 

It is usually not a very good idea to complicate the testing framework
with configuration files (as then you will have two things to be
tested). Unless the testing data is very huge (so huge that it
interferes with reading and writing the testing code), and huge data is
necessary for the test, it is much simpler and better to just put the
data into the test code. In cases where you want to have fairly complex
object (list, etc) you can "import" the test data. Pickling is usually
unnecessary unless you want to store instance data (classes, etc).

-- code.py --
def add(a, b):
    return a + b

-- test.py --
import unittest

# import the file we're testing
import code

# imports the data from separate file
from testdata import data

class AddCase(unittest.TestCase):
    def test_add():
        for case in data:
            self.assertEqual(code.add(case[0], case[1]), case[2])

-- testdata.py --
data = [(0, 0, 0),
        (1, 0, 1),
        (0, 1, 1),
        (1, -1, 0),
       ]


From pm567426 at gmail.com  Tue Jul  7 07:06:07 2009
From: pm567426 at gmail.com (Pedram)
Date: Tue, 7 Jul 2009 04:06:07 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com> 
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com> 
	<173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com> 
	<2169e268-3fa7-4320-bef0-2619b8d1d040@h8g2000yqm.googlegroups.com>
Message-ID: <06ec69cc-2183-41b6-92ac-eafaa3b5cd02@n11g2000yqb.googlegroups.com>

On Jul 7, 1:10?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 6, 4:13?pm, Pedram <pm567... at gmail.com> wrote:
>
>
>
> > On Jul 6, 5:46?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> > > On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
>
> > > > OK, fine, I read longobject.c at last! :)
> > > > I found that longobject is a structure like this:
>
> > > > struct _longobject {
> > > > ? ? struct _object *_ob_next;
> > > > ? ? struct _object *_ob_prev;
>
> > > For current CPython, these two fields are only present in debug
> > > builds; ?for a normal build they won't exist.
>
> > I couldn't understand the difference between them. What are debug
> > build and normal build themselves? And You mean in debug build
> > PyLongObject is a doubly-linked-list but in normal build it is just an
> > array (Or if not how it'll store in this mode)?
>
> No: ?a PyLongObject is stored the same way (ob_size giving sign and
> number of digits, ob_digit giving the digits themselves) whether or
> not a debug build is in use.
>
> A debug build does various things (extra checks, extra information) to
> make it easier to track down problems. ?On Unix-like systems, you can
> get a debug build by configuring with the --with-pydebug flag.
>
> The _ob_next and _ob_prev fields have nothing particularly to do with
> Python longs; for a debug build, these two fields are added to *all*
> Python objects, and provide a doubly-linked list that links all 'live'
> Python objects together. ?I'm not really sure what, if anything, the
> extra information is used for within Python---it might be used by some
> external tools, I guess.
>
> Have you looked at the C-API documentation?
>
> http://docs.python.org/c-api/index.html
>
> _ob_next and _ob_prev are described here:
>
> http://docs.python.org/c-api/typeobj.html#_ob_next
>
> (These docs are for Python 2.6; ?I'm not sure what version you're
> working with.)
>
> Mark

It seems there's an island named Python!
Thanks for links, I'm on reading them.


From serverin2000 at yahoo.com  Tue Jul  7 07:07:46 2009
From: serverin2000 at yahoo.com (RAM)
Date: Tue, 7 Jul 2009 04:07:46 -0700 (PDT)
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
	<d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
	<mailman.2678.1246870949.8015.python-list@python.org>
Message-ID: <df23f0da-6b9c-4dd8-8b6b-b29a12bcc5cb@a39g2000pre.googlegroups.com>

On 6 July, 10:02, Simon Brunning <si... at brunningonline.net> wrote:
> 2009/7/6 RAM <serverin2... at yahoo.com>:
>
> > I am trying to do this on windows. My program(executable) has been
> > written in VC++ and when I run this program, I need to click on one
> > button on the program GUI i,e just I am entering "Enter key" on the
> > key board. But this needs manual process. So i need to write a python
> > script which invokes my program and pass "Enter key" event to my
> > program so that it runs without manual intervention.
>
> Try <http://pywinauto.openqa.org/>.
>
> --
> Cheers,
> Simon B.

Thank you all for the help the below url helped me in accomplishing my
task

http://www.rutherfurd.net/python/sendkeys/index.html

regards
Sreerama V


From no.email at please.post  Tue Jul  7 07:50:01 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 11:50:01 +0000 (UTC)
Subject: ISO library ref in printed form
Message-ID: <h2vcp9$66b$1@reader1.panix.com>



Does anyone know where I can buy the Python library reference in
printed form?  (I'd rather not print the whole 1200+-page tome
myself.)  I'm interested in both/either 2.6 and 3.0.

TIA!

kj


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 07:51:11 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 13:51:11 +0200
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <4a5336a8$0$11315$426a74cc@news.free.fr>

kj a ?crit :
> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
> 
>> kj a ?crit :
>> (snipo
>>> To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism,
> 
>> FWIW, Python has no pretention to minimalism.
> 
> Assuming that you mean by this that Python's authors have no such
> pretensions:
> 
> "There is real value in having a small language."
> 
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html

There are some differences between "small" and "minimal"...

> So there.
> 
> BTW, that's just one example.  I've seen similar sentiments expressed
> by Guido over and over and over: any new proposed enhancement to
> Python must be good enough in his mind to justify cluttering the
> language.  That attitude counts as minimalism in my book.

And in mine, it counts as "keeping the language's evolution under 
control" - which is still not the same thing as being "minimalist". If 
Python really was on the "minimalist" side, you wouldn't even have 
"class" or "def" statements - both being mostly syntactic sugar. And 
let's not even talk about @decorator syntax...



From dnhkng at googlemail.com  Tue Jul  7 08:00:09 2009
From: dnhkng at googlemail.com (Dr Mephesto)
Date: Tue, 7 Jul 2009 05:00:09 -0700 (PDT)
Subject: Python/pyobjC Apps on iPhone now a possibility?
Message-ID: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>

I have been following the discussion about python and pyobjc on the
iphone, and it seemed to me that the app-store rules prohibited
embedded interpreters; so, python apps are a no-no.

But now it seems that the Rubyists have the option that we don't. It
seems there is a company, http://rhomobile.com/home, that has an SDK
that allows ruby programs to be embedded together with an interpreter
in an app! More interesting is the fact that several of these hybrid
apps seem to have been accepted on the itunes app store.

Here's a quote from a representative, found on this blog:
http://www.rubyinside.com/rhodes-develop-full-iphone-rim-and-symbian-apps-using-ruby-1475.html

"...First of all, to clarify, we precompile all framework and app code
down to Ruby 1.9 VM bytecode. This yields great performance
advantages. We also disable eval and other dynamic execution aspects
of Ruby. In the end, on all platforms your app gets compiled with our
framework all into one single executable, indistinguishable from any
other executable.

But even if we were shipping a fullon Ruby interpreter without
compiling to bytecode and leaving dynamic evaluation enabled (as has
been well remarked in the blogosphere by now) App Store rule 3.3.2
does not disallow interpreters but only downloading code to be
executed by the interpreter."

So, the question is, can the same thing be done for Python apps?


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 08:00:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 12:00:33 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
	<006eb461$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2755.1246947020.8015.python-list@python.org>
Message-ID: <006f13c9$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 22:18:20 -0700, Chris Rebert wrote:

>> Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.
[...]
> Well, yes, but when would you apply it twice in a row?

My point was that unary + isn't a no-op, and therefore neither is ++. For 
Decimal, I can't think why you'd want to apply ++x, but for other 
objects, who knows?

Here's a toy example:

>>> class Spam(str):
...     def __pos__(self):
...         return self.__class__("spam " + self)
...
>>> s = Spam("")
>>> ++++s
'spam spam spam spam '



-- 
Steven


From david.lyon at preisshare.net  Tue Jul  7 08:02:07 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 07 Jul 2009 08:02:07 -0400
Subject: Where does setuptools =?UTF-8?Q?live=3F?=
In-Reply-To: <4A530219.6040007@simplistix.co.uk>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
Message-ID: <eff5e178f7200eec6637807f209b8d2d@preisshare.net>

On Tue, 07 Jul 2009 09:06:49 +0100, Chris Withers <chris at simplistix.co.uk>
wrote:
>> What hasn't happened is enough testing of pypi packages and installing
>> with setuptools/pip/enstall from pypi.
> 
> What needs testing?

It's software... therefore it needs testing...

David




From paul.nospam at rudin.co.uk  Tue Jul  7 08:03:54 2009
From: paul.nospam at rudin.co.uk (Paul Rudin)
Date: Tue, 07 Jul 2009 13:03:54 +0100
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
	<4a5336a8$0$11315$426a74cc@news.free.fr>
Message-ID: <87prccsnrp.fsf@rudin.co.uk>

Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:

> kj a ?crit :
>> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
>>
>>> kj a ?crit :
>>> (snipo
>>>> To have a special-case
>>>> re.match() method in addition to a general re.search() method is
>>>> antithetical to language minimalism,
>>
>>> FWIW, Python has no pretention to minimalism.
>>
>> Assuming that you mean by this that Python's authors have no such
>> pretensions:
>>
>> "There is real value in having a small language."
>>
>> 			Guido van Rossum, 2007.07.03
>> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
>
> There are some differences between "small" and "minimal"...
>

There's also a difference between the language and its standard
library.


From chris at simplistix.co.uk  Tue Jul  7 08:07:48 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 13:07:48 +0100
Subject: Where does setuptools live?
In-Reply-To: <eff5e178f7200eec6637807f209b8d2d@preisshare.net>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
	<eff5e178f7200eec6637807f209b8d2d@preisshare.net>
Message-ID: <4A533A94.7030503@simplistix.co.uk>

David Lyon wrote:
> On Tue, 07 Jul 2009 09:06:49 +0100, Chris Withers <chris at simplistix.co.uk>
> wrote:
>>> What hasn't happened is enough testing of pypi packages and installing
>>> with setuptools/pip/enstall from pypi.
>> What needs testing?
> 
> It's software... therefore it needs testing...

Yes, which is why I asked WHAT needs testing? :-)

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From david.lyon at preisshare.net  Tue Jul  7 08:21:50 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 07 Jul 2009 08:21:50 -0400
Subject: Where does setuptools =?UTF-8?Q?live=3F?=
In-Reply-To: <4A533A94.7030503@simplistix.co.uk>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
	<eff5e178f7200eec6637807f209b8d2d@preisshare.net>
	<4A533A94.7030503@simplistix.co.uk>
Message-ID: <fc81c0a388e0f1788508dfdaaa58344e@preisshare.net>

On Tue, 07 Jul 2009 13:07:48 +0100, Chris Withers <chris at simplistix.co.uk>
wrote:
>>>> What hasn't happened is enough testing of pypi packages and installing
>>>> with setuptools/pip/enstall from pypi.
>>> What needs testing?
>> 
>> It's software... therefore it needs testing...
> 
> Yes, which is why I asked WHAT needs testing? :-)

I've written a package manager gui. I think it is
orderly to comprehensively ascertain which packages will 
and won't install from pypi with the tool.

I'll run the same install test for pip, easyinstall 
and enstall. And come up with a preferred installer.

Which I will then suggest as the preferred tool.

David




From chris at simplistix.co.uk  Tue Jul  7 08:28:14 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 13:28:14 +0100
Subject: Where does setuptools live?
In-Reply-To: <fc81c0a388e0f1788508dfdaaa58344e@preisshare.net>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
	<eff5e178f7200eec6637807f209b8d2d@preisshare.net>
	<4A533A94.7030503@simplistix.co.uk>
	<fc81c0a388e0f1788508dfdaaa58344e@preisshare.net>
Message-ID: <4A533F5E.1080004@simplistix.co.uk>

David Lyon wrote:
> I've written a package manager gui. I think it is
> orderly to comprehensively ascertain which packages will 
> and won't install from pypi with the tool.
> 
> I'll run the same install test for pip, easyinstall 
> and enstall. And come up with a preferred installer.
> 
> Which I will then suggest as the preferred tool.

Cool :-)

If you can publish your results or make the raw data downloadable 
somewhere (especially which packages fail with which installers) I'm 
sure a lot of people would find that *very* interesting...

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From zdenekmaxa at yahoo.co.uk  Tue Jul  7 08:38:16 2009
From: zdenekmaxa at yahoo.co.uk (Zdenek Maxa)
Date: Tue, 07 Jul 2009 14:38:16 +0200
Subject: Tkinter.Canvas thread safety problem?
Message-ID: <4A5341B8.5000502@yahoo.co.uk>

Hello,

I have started a project using Tkinter. The application performs some
regular checks in a thread and updates Canvas components. I have
observed that sometimes the application hangs when it is about to call
canvas.itemconfig() when the thread is about to terminate in the next loop.

Experimenting with this problem for a while, I have compiled a little
example which always reproduces the problem. Commenting out the line 52
(before canvas.itemconfig()), the example always finishes all right,
having the delay there, it hangs.

I would like to ask if you could have a look at the snippet in the
attachment and tell me if that is actually me doing something wrong or
indeed Tkinter thread safety problem and what the workaround could be.

Could you please also comment on wxPython thread safety?

I am using:

Python 2.5.4 (r254:67916, Feb 17 2009, 20:16:45)
[GCC 4.3.3]

2.6.26-1-amd64 #1 SMP Fri Mar 13 19:34:38 UTC 2009 x86_64 GNU/Linux

Thanks in advance,
Zdenek
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tkinter_thread_safety.py
Type: text/x-python
Size: 2278 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/de3e4d7b/attachment.py>

From lie.1296 at gmail.com  Tue Jul  7 08:48:34 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 12:48:34 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006ebea2$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<h2nqpf$d91$1@reader1.panix.com>	<mailman.2688.1246883548.8015.python-list@python.org>	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <CuH4m.3259$ze1.429@news-server.bigpond.net.au>

Steven D'Aprano wrote:
> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
> 
>> When people are fighting over things like `sense`, although sense may
>> not be strictly wrong dictionary-wise, it smells of something burning...
> 
> That would be my patience.
> 
> I can't believe the direction this discussion has taken.

Me neither.

> Anybody sensible 
> would be saying "Oh wow, I've just learned a new meaning to the word, 
> that's great, I'm now less ignorant than I was a minute ago". But oh no, 
> we mustn't use a standard meaning to a word, heaven forbid we disturb 
> people's ignorance by teaching them something new.

A meaning of a word is meaningless if nobody apart the writer
understands it. The purpose of code is 1) to communicate with the
computer, 2) to communicate with fellow programmer. The second point is
especially important if the code are written for pedantic purpose.
Teaching is largely one-way communication and often students that does
not understand about a slight point could not or would not communicate
their feelings because they think it is too silly. If the use of word is
criticized on a two-way communication channel (e.g. newsgroup), it
should raise a question of whether the word should be described first or
whether a synonym would be more suitable for the purpose. Most of these
do not apply on practical, non-pedantic purpose though, since in
non-pedantic settings you are expected to know and use the jargons
however (in)sensible they may be at first sight.

> It's as simple as this: using `sense` as a variable name to record the 
> sense of a function is not a code smell, any more than using `flag` to 
> record a flag would be, or `sign` to record the sign of an object.

Nobody said code smell... linguistic smell is more appropriate.

> If you 
> don't know the appropriate meanings of the words sense, flag or sign, 
> learn them, don't dumb down my language.


From jeanmichel at sequans.com  Tue Jul  7 08:51:10 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 07 Jul 2009 14:51:10 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006ebea2$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<h2nqpf$d91$1@reader1.panix.com>	<mailman.2688.1246883548.8015.python-list@python.org>	<006e795f$0$9711$c3e8da3@news.astraweb.com>	<h2uhcb$blq$1@panix3.panix.com>	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <4A5344BE.2080006@sequans.com>

Steven D'Aprano wrote:
> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
>
>   
>> When people are fighting over things like `sense`, although sense may
>> not be strictly wrong dictionary-wise, it smells of something burning...
>>     
>
> That would be my patience.
>
> I can't believe the direction this discussion has taken. Anybody sensible 
> would be saying "Oh wow, I've just learned a new meaning to the word, 
> that's great, I'm now less ignorant than I was a minute ago". But oh no, 
> we mustn't use a standard meaning to a word, heaven forbid we disturb 
> people's ignorance by teaching them something new.
>
> It's as simple as this: using `sense` as a variable name to record the 
> sense of a function is not a code smell, any more than using `flag` to 
> record a flag would be, or `sign` to record the sign of an object. If you 
> don't know the appropriate meanings of the words sense, flag or sign, 
> learn them, don't dumb down my language.
>
>   

Can't we just calm down ? I'm really sorry my ignorance started this 
thread, and my apologies go to Kj who's obviously more fluent in english 
than me.
I've never used sense in that way before, nor I've seen used by others 
until now. However Kj is right, and my dictionary seems wrong 
(wordreference.com). I've searched through others dictionaries and find 
out this is actually applicable to functions. My bad.

JM


From davea at ieee.org  Tue Jul  7 08:55:13 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 08:55:13 -0400
Subject: Python Error from Apress book
In-Reply-To: <op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A5345B1.8050306@ieee.org>

Gabriel Genellina wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">En Mon, 
> 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com> escribi?:
>
>> When I try to run the command as outlined in
>> the book "simple_markup2.py < test_input.txt > test_output.html i get 
>> the
>> following error every time.
>>
>> IOError: [Errno 9] Bad file descriptor
>
> That's a Windows problem. When you execute the script as itself 
> (either as you do in the command line, or by double-clicking on it), 
> it doesn't have valid standard handles.
> You have to invoke Python explicitely:
>
> python simple_markup2.py < test_input.txt > test_output.html
>
> (you may need to specify the full path to python.exe, or add the 
> directory where Python is installed to your system PATH).
>
I use stdout this way all the time, with no problem (python 2.6, Windows 
XP).  But as you point out, stdin redirection doesn't seem to work using 
the file associations.  I do get a different error though. When I look 
at sys.stdin, it shows an open file, with handle of zero, as expected.  
But when I do a raw_input(), it gets:
     EOFError: EOF when reading a line




From stefan_ml at behnel.de  Tue Jul  7 09:01:07 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 15:01:07 +0200
Subject: parsing times like "5 minutes ago"?
In-Reply-To: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
Message-ID: <4a534713$0$31332$9b4e6d93@newsspool4.arcor-online.net>

mh at pixar.com wrote:
> I'm looking for something like Tcl's [clock scan] command which parses
> human-readable time strings such as:
> 
>     % clock scan "5 minutes ago"
>     1246925569
>     % clock scan "tomorrow 12:00"
>     1246993200
>     % clock scan "today + 1 fortnight"
>     1248135628
> 
> Does any such package exist for Python?

Is this only for English times or is I18N a concern?

Stefan


From python at mrabarnett.plus.com  Tue Jul  7 09:07:00 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 14:07:00 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2ujrs$4c0$1@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
Message-ID: <4A534874.8050503@mrabarnett.plus.com>

Dennis Lee Bieber wrote:
> On Mon, 6 Jul 2009 19:48:39 -0700, Daniel Fetchinson
> <fetchinson at googlemail.com> declaimed the following in
> gmane.comp.python.general:
> 
>> Yes, there are plenty of languages other than Java and C, but the
>> influence of C is admittedly huge in Python. Why do you think loops
>> are called "for", conditionals "if" or "while", functions return via
>> "return", loops terminate via "break" and keep going via "continue"
>> and why is comparison written as "==", etc, etc? All of these are
>> coming from C (or an even earlier language) and my point is that users
> 
> 	for, if, and return were common keywords in FORTRAN.
> 
> 	Not to mention BASIC
> 
> 	Both of which predate C
> 
FORTRAN also used "=" for assignment (and ".EQ." for comparison).

C was derived from BCPL which used ":=" for assignment and "=" for
comparison.


From james at agentultra.com  Tue Jul  7 09:07:58 2009
From: james at agentultra.com (J Kenneth King)
Date: Tue, 07 Jul 2009 09:07:58 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
Message-ID: <85ljn0ej4h.fsf@agentultra.com>

Dr Mephesto <dnhkng at googlemail.com> writes:

> I have been following the discussion about python and pyobjc on the
> iphone, and it seemed to me that the app-store rules prohibited
> embedded interpreters; so, python apps are a no-no.
>
> But now it seems that the Rubyists have the option that we don't. It
> seems there is a company, http://rhomobile.com/home, that has an SDK
> that allows ruby programs to be embedded together with an interpreter
> in an app! More interesting is the fact that several of these hybrid
> apps seem to have been accepted on the itunes app store.
>
> Here's a quote from a representative, found on this blog:
> http://www.rubyinside.com/rhodes-develop-full-iphone-rim-and-symbian-apps-using-ruby-1475.html
>
> "...First of all, to clarify, we precompile all framework and app code
> down to Ruby 1.9 VM bytecode. This yields great performance
> advantages. We also disable eval and other dynamic execution aspects
> of Ruby. In the end, on all platforms your app gets compiled with our
> framework all into one single executable, indistinguishable from any
> other executable.
>
> But even if we were shipping a fullon Ruby interpreter without
> compiling to bytecode and leaving dynamic evaluation enabled (as has
> been well remarked in the blogosphere by now) App Store rule 3.3.2
> does not disallow interpreters but only downloading code to be
> executed by the interpreter."
>
> So, the question is, can the same thing be done for Python apps?

I love Python and all, but it'd be apt to ask, what's the point?

The iPhone is running on what? A 400Mhz ARM processor? Resources on the
device are already limited; running your program on top of an embedded
Python interpreter would only be adding pressure to the constraints;
even if it was an optimized interpreter.

Might as well just suck it up and learn C/Objective-C .. it's really not
that hard. It took me about a day to pick up the language and another
two or three to finagle with the libraries.


From davea at ieee.org  Tue Jul  7 09:10:14 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 09:10:14 -0400
Subject: module name versus function name resolution conflict.
In-Reply-To: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
References: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
Message-ID: <4A534936.7060300@ieee.org>

rocky wrote:
> Someone recently reported a problem in pydb where a function defined
> in his program was conflicting with a module name that pydb uses. I
> think I understand what's wrong, but I don't have any elegant
> solutions to the problem. Suggestions would be appreciated.
>
> In a nutshell, here's the problem:
>
> In file fns:
>
>   def foo(): print "foo"
>
> In file pdebug.py:
>
>   import fns, sys
>
>   def trace_dispatch(frame, event, arg):
>       fns.foo()
>       print frame, event, arg
>       return trace_dispatch
>
>   sys.settrace(trace_dispatch)
>   execfile('myprogram.py')
>
> Finally file myprogram.py:
>
>   def fns(): print "This is the *other* fns"
>
> When you run pdebug.py you get:
>
> $ python pdebug.py
> foo
> <frame object at 0xdd9030> call None
> foo
> <frame object at 0xdd9030> line None
> Traceback (most recent call last):
>   File "pdebug.py", line 7, in <module>
>     execfile('myprogram.py')
>   File "myprogram.py", line 1, in <module>
>     def fns(): print "This is the *other* fns"
>   File "pdebug.py", line 3, in trace_dispatch
>     fns.foo()
> AttributeError: 'function' object has no attribute 'foo'
>
>
> Basically inside the trace hook, local functions are visible and take
> precedence over (global) module names. I could move "import fns"
> inside trace_dispatch(), but I'd have to do that in all of the methods
> that module "fns" is used.  Also note that using the form:
>   from fns import foo
>
> would eliminate the conflict on "fns", but I'd still have potential
> conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> reduce the chance of a conflict but not eliminate it.
>
> Suggestions?
>
>
>   
Some context would be useful.  For example, you may be writing pdebug.py 
as a library to be used by other developers, and you want to minimize 
the likelihood that arbitrary code they write will conflict.  If you own 
all the code, I'd just say to rename one or the other.

My preference is also for using import of myprogram, as I've never 
needed execfile().  But if you need one of the features of execfile(), 
and really want myprogram in the same namespace, then you probably ought 
to obfuscate the other import.

Instead of   import fns,    try:
       import fns as _module_fns
And of course any references to the module will use the longer name.

The leading underscore is a clue that the name is not to be used outside 
of the module.  And the prefix 'module' helps to make it unlikely 
they'll make a data or function or class with that name.




From philip at semanchuk.com  Tue Jul  7 09:18:32 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Tue, 7 Jul 2009 09:18:32 -0400
Subject: How to map size_t using ctypes?
In-Reply-To: <op.uwn9hrmpx6zn5v@lepton.softlabbsas.com.ar>
References: <mailman.2691.1246888326.8015.python-list@python.org>
	<7belo1F21fs3vU1@mid.uni-berlin.de>
	<DB4ED723-C8DD-492F-A7CC-B3CE14F8B723@semanchuk.com>
	<op.uwn9hrmpx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <9DD9E3DD-1C6E-4B12-A9DD-9F768832DF60@semanchuk.com>


On Jul 6, 2009, at 11:51 PM, Gabriel Genellina wrote:

> En Mon, 06 Jul 2009 13:29:21 -0300, Philip Semanchuk
> <philip at semanchuk.com> escribi?:
>> On Jul 6, 2009, at 12:10 PM, Diez B. Roggisch wrote:
>>> Philip Semanchuk wrote:
>>>
>>>> I can't figure out how to map a C variable of size_t via Python's
>>>> ctypes module.
>>>
>>> from ctypes import c_size_t
>>
>> D'oh! [slaps forehead]
>>
>> That will teach me to RTFM. [...] You'd be surprised at the amount  
>> of Googling I did without learning this on my own.
>
> Yep, seems like these terms in particular are hard to find.  
> Searching for
> +ctypes +size_t, the first "good" result comes only at page 3. Bad  
> luck...
> :(

Fortunately, through my ignorance I may provide enlightenment...this  
conversation is now hit #3 on page 1 =)

If I paste the URL here, will I create an infinite loop?
http://www.google.com/search?q=%2Bctypes+%2Bsize_t




From dnhkng at googlemail.com  Tue Jul  7 09:23:25 2009
From: dnhkng at googlemail.com (Dr Mephesto)
Date: Tue, 7 Jul 2009 06:23:25 -0700 (PDT)
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
Message-ID: <fc6b4e6a-5e89-4fed-914b-232fc6b1cf0e@h18g2000yqj.googlegroups.com>

Sure, I am learning Objective C already, but the syntax is really
unfriendly after python.

I think it really depends on the type of app you want to write.
Anything held back by network delays or that sits around waiting for
user input are perfectly acceptable target apps. If you need speed for
something really intensive, falling back to C is still much nicer than
coding in Objective C. I agree that having a certain basic
understanding of objective C is a must, but having the option to use a
coder-friendly language like Ruby or Python can cut development time
dramatically.

If Ruby can do it (and it generally slower than python), why can
Python also get a legal iPhone interpreter?



From deets at nospam.web.de  Tue Jul  7 09:23:34 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 07 Jul 2009 15:23:34 +0200
Subject: Tkinter.Canvas thread safety problem?
References: <mailman.2764.1246970677.8015.python-list@python.org>
Message-ID: <7bh0anF22udtoU1@mid.uni-berlin.de>

Zdenek Maxa wrote:

> Hello,
> 
> I have started a project using Tkinter. The application performs some
> regular checks in a thread and updates Canvas components. I have
> observed that sometimes the application hangs when it is about to call
> canvas.itemconfig() when the thread is about to terminate in the next
> loop.
> 
> Experimenting with this problem for a while, I have compiled a little
> example which always reproduces the problem. Commenting out the line 52
> (before canvas.itemconfig()), the example always finishes all right,
> having the delay there, it hangs.
> 
> I would like to ask if you could have a look at the snippet in the
> attachment and tell me if that is actually me doing something wrong or
> indeed Tkinter thread safety problem and what the workaround could be.
> 
> Could you please also comment on wxPython thread safety?
> 

As a rule of thumb, GUI-toolkits aren't threadsafe. Qt being a notable
exception to this rule.

There are various ways to cope with this, mostly through injecting events
into the event-queue of the main gui thread, or using timers.

This is also true for wx (google wx python threading for a plethora of
information on this)

For Tx, I dimly remember an "after" function that can be used to invoke
timer-based code. Use that to update aggregated data from the events.

Diez


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 09:23:49 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 15:23:49 +0200
Subject: Why re.match()?
In-Reply-To: <87prccsnrp.fsf@rudin.co.uk>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>	<4a4e2227$0$7801$426a74cc@news.free.fr>	<h2tngh$12s$1@reader1.panix.com>	<4a5336a8$0$11315$426a74cc@news.free.fr>
	<87prccsnrp.fsf@rudin.co.uk>
Message-ID: <4a534c5e$0$414$426a74cc@news.free.fr>

Paul Rudin a ?crit :
> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
> 
>> kj a ?crit :
>>> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
>>>
>>>> kj a ?crit :
>>>> (snipo
>>>>> To have a special-case
>>>>> re.match() method in addition to a general re.search() method is
>>>>> antithetical to language minimalism,
>>>> FWIW, Python has no pretention to minimalism.
>>> Assuming that you mean by this that Python's authors have no such
>>> pretensions:
>>>
>>> "There is real value in having a small language."
>>>
>>> 			Guido van Rossum, 2007.07.03
>>> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
>> There are some differences between "small" and "minimal"...
>>
> 
> There's also a difference between the language and its standard
> library.

Indeed.


From pdpinheiro at gmail.com  Tue Jul  7 09:37:02 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 06:37:02 -0700 (PDT)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1> 
	<h2hap5$qv8$2@reader1.panix.com>
Message-ID: <d6d77204-3c1c-4374-92d1-8383bf5bc890@a7g2000yqk.googlegroups.com>

On Jul 2, 4:49?am, kj <no.em... at please.post> wrote:
> In <Xns9C3BCA27ABC36duncanbo... at 127.0.0.1> Duncan Booth <duncan.bo... at invalid.invalid> writes:
>
> >So, for example:
> >>>> re.compile("c").match("abcdef", 2)
> ><_sre.SRE_Match object at 0x0000000002C09B90>
> >>>> re.compile("^c").search("abcdef", 2)
>
> I find this unconvincing; with re.search alone one could simply
> do:
>
> >>> re.compile("^c").search("abcdef"[2:])

given large enough values of "abcdef", you just allocated several megs
for no good reason, when re.compile("c").match("abcdef", 2) would
process "abcdef" in-place.


From davea at ieee.org  Tue Jul  7 09:38:37 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 09:38:37 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <Xns9C4173416946Fduncanbooth@127.0.0.1>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>	<mailman.2753.1246941897.8015.python-list@python.org>
	<Xns9C4173416946Fduncanbooth@127.0.0.1>
Message-ID: <4A534FDD.8030105@ieee.org>

Duncan Booth wrote:
> Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:
>
>   
>> for, if, and return were common keywords in FORTRAN.
>>     
>
> Really? What does 'for' do in FORTRAN?
>
> P.S. Does FORTRAN actually have keywords these days? Back when I learned it 
> there was no such thing as a reserved word though for all I know they may 
> have since added them.
>
>   
The way I remember it (last used Fortran in 1970), DO was the looping 
construct, not FOR.  Naturally it was uppercase, as keypunches of the 
time didn't have an easy way to do lowercase.  (It was possible, you 
just had to use multi-punch, and a good memory for the appropriate 
0-12-11 prefixes).




From piet at cs.uu.nl  Tue Jul  7 09:41:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 15:41:46 +0200
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
	<comdnVhXl4M6bczXnZ2dnUVZ_g2dnZ2d@pdx.net>
	<006e79e9$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <m2ljn0d2zp.fsf@cs.uu.nl>

>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:

>SD> On Mon, 06 Jul 2009 05:47:18 -0700, Scott David Daniels wrote:
>>> Steven D'Aprano wrote:
>>>> ... That's the Wrong Way to do it --
>>>> you're using a screwdriver to hammer a nail....
>>> 
>>> Don't knock tool abuse (though I agree with you here). Sometimes tool
>>> abuse can produce good results.  For example, using hammers to drive
>>> screws for temporary strong holds led to making better nails.

>SD> Historically, nails were invented a long time before screws. Screws as 
>SD> fasteners weren't invented until the 1400s, nails were used thousands of 
>SD> years ago.

>SD> And hammering screws makes temporary *weak* holds, not strong, because 
>SD> the screw only touches the sides of the hole lightly. Unless the screw 
>SD> has been specifically designed to be hammered, hammering screws is pretty 
>SD> much the definition of incompetence and/or laziness!

In our language (Dutch, i.e. Guido's mother tongue) `American
screwdriver' is an expression meaning `hammer' :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nile_mcadams at yahoo.com  Tue Jul  7 09:45:12 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Tue, 7 Jul 2009 06:45:12 -0700 (PDT)
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <97697cdc-e6b3-4277-b26e-d859ee4cd499@h31g2000yqd.googlegroups.com>

Thanks all for your help. I appreciate it.  The problem was in the
function.  A simple bug which I should have caught but I had my mental
blinders on and was sure the problem was outside the function.  The
answers have given me a lot to learn so thanks for that as well.


From __peter__ at web.de  Tue Jul  7 09:50:35 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 07 Jul 2009 15:50:35 +0200
Subject: Tkinter.Canvas thread safety problem?
References: <mailman.2764.1246970677.8015.python-list@python.org>
Message-ID: <h2vjq9$lb5$03$1@news.t-online.com>

Zdenek Maxa wrote:

> I would like to ask if you could have a look at the snippet in the
> attachment and tell me if that is actually me doing something wrong or
> indeed Tkinter thread safety problem and what the workaround could be.

http://effbot.org/zone/tkinter-threads.htm



From CHausberger at gmx.de  Tue Jul  7 09:59:49 2009
From: CHausberger at gmx.de (Claus Hausberger)
Date: Tue, 07 Jul 2009 15:59:49 +0200
Subject: Problem reading file with umlauts
Message-ID: <20090707135949.100950@gmx.net>

Hello

I have a text file with is encoding in Latin1 (ISO-8859-1). I can't change that as I do not create those files myself.

I have to read those files and convert the umlauts like ? to stuff like &oumol; as the text files should become html files.

I have this code:


#!/usr/bin/python
# -*- coding: latin1 -*-

import codecs

f = codecs.open('abc.txt', encoding='latin1')

for line in f:
    print line
    for c in line: 
        if c == "?":
            print "oe"
        else:
            print c


and I get this error message:

$ ./read.py
Abc

./read.py:11: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
  if c == "?":
A
b
c



Traceback (most recent call last):
  File "./read.py", line 9, in <module>
    print line
UnicodeEncodeError: 'ascii' codec can't encode characters in position 0-3: ordinal not in range(128)




I checked the web and tried several approaches but I also get some strange encoding errors.
Has anyone ever done this before? 
I am currently using Python 2.5 and may be able to use 2.6 but I cannot yet move to 3.1 as many libs we use don't yet work with Python 3.

any help more than welcome.  This has been driving me crazy for two days now.

best wishes

Claus
-- 
Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
f?r nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


From stefan_ml at behnel.de  Tue Jul  7 10:04:09 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 16:04:09 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <mailman.2774.1246975200.8015.python-list@python.org>
References: <mailman.2774.1246975200.8015.python-list@python.org>
Message-ID: <4a5355d9$0$31339$9b4e6d93@newsspool4.arcor-online.net>

Claus Hausberger wrote:
> Hello
> 
> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't change that as I do not create those files myself.
> 
> I have to read those files and convert the umlauts like ? to stuff like &oumol; as the text files should become html files.
> 
> I have this code:
> 
> 
> #!/usr/bin/python
> # -*- coding: latin1 -*-
> 
> import codecs
> 
> f = codecs.open('abc.txt', encoding='latin1')
> 
> for line in f:
>     print line
>     for c in line: 
>         if c == "?":

You are reading Unicode strings, so you have to compare it to a unicode
string as in

	if c == u"?":

>             print "oe"
>         else:
>             print c

Note that printing non-ASCII characters may not always work, depending on
your terminal.

Stefan


From sajmikins at gmail.com  Tue Jul  7 10:18:30 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 10:18:30 -0400
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
Message-ID: <50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>

On Mon, Jul 6, 2009 at 7:00 PM, <nacim_bravo at agilent.com> wrote:
> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment?
>
> Please let me know,
> nacim
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>

The answers to your first and third questions are, "yes" and "yes". :]
 (Generally speaking if something can be done by a computer it can be
done with python.)

As for your second question check out the "magnitude" package:

http://pypi.python.org/pypi/magnitude/   and
http://juanreyero.com/magnitude/

(That second link also has links to three other packages that deal
with units of measurement.)

Ii has units for the SI measurements, including volts and coulombs, so
you should be able to accomplish your goals with it.

The tricky thing is, as far as I can tell from the wikipedia entry
(http://en.wikipedia.org/wiki/Relative_static_permittivity),
"dielectric constant" seems to be a dimensionless number, i.e. C/C...
 I could be totally daft though.

HTH,
~Simon


From sajmikins at gmail.com  Tue Jul  7 10:22:48 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 07:22:48 -0700 (PDT)
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <c32e8f23-7a33-494e-8a92-fdd86403d627@d32g2000yqh.googlegroups.com>

On Jul 6, 6:02?pm, Michael Mossey <michaelmos... at gmail.com> wrote:
> On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>
> > On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>
> > > What is required in a python program to make sure it catches a ?
> > > control-
> > > c on the command-line? Do some i/o? The OS here is Linux.
>
> > You can use a try/except to catch a KeyboardInterrupt exception, or ?
> > you can trap it using the signal module:http://docs.python.org/library/signal.html
>
> > You want to trap SIGINT.
>
> > HTH
> > Philip
>
> Thanks to both of you. However, my question is also about whether I
> need to be doing i/o or some similar operation for my program to
> notice in any shape or form that Control-C has been pressed. In the
> past, I've written Python programs that go about their business
> ignoring Ctrl-C. Other programs respond to it immediately by exiting.
> I think the difference is that the latter programs are doing i/o. But
> I want to understand better what the "secret" is to responding to a
> ctrl-C in any shape or form.
>
> For example, does trapping SIGINT always work, regardless of what my
> process is doing?
>
> Thanks,
> Mike

Try some experiments. ;]


From aahz at pythoncraft.com  Tue Jul  7 10:41:59 2009
From: aahz at pythoncraft.com (Aahz)
Date: 7 Jul 2009 07:41:59 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2765.1246971084.8015.python-list@python.org>
Message-ID: <h2vmrn$3oh$1@panix3.panix.com>

In article <mailman.2765.1246971084.8015.python-list at python.org>,
Jean-Michel Pichavant  <jeanmichel at sequans.com> wrote:
>
>Can't we just calm down ? I'm really sorry my ignorance started this 
>thread, and my apologies go to Kj who's obviously more fluent in english 
>than me.
>I've never used sense in that way before, nor I've seen used by others 
>until now. However Kj is right, and my dictionary seems wrong 
>(wordreference.com). I've searched through others dictionaries and find 
>out this is actually applicable to functions. My bad.

You were not the first person to point out that "sense" is a poor
variable name.  Unless KJ is specifically using this code in the context
of a math class, I still think that "sense" is completely inappropriate.
Your English fluency is just fine.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From hubaghdadi at gmail.com  Tue Jul  7 10:46:18 2009
From: hubaghdadi at gmail.com (Hussein B)
Date: Tue, 7 Jul 2009 07:46:18 -0700 (PDT)
Subject: Remoting over SSH
Message-ID: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>

Hey,
I want to perform commands on a remote server over SSH.
What do I need?
Thanks.


From aahz at pythoncraft.com  Tue Jul  7 10:47:49 2009
From: aahz at pythoncraft.com (Aahz)
Date: 7 Jul 2009 07:47:49 -0700
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
Message-ID: <h2vn6l$klq$1@panix3.panix.com>

In article <85ljn0ej4h.fsf at agentultra.com>,
J Kenneth King  <james at agentultra.com> wrote:
>
>The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>device are already limited; running your program on top of an embedded
>Python interpreter would only be adding pressure to the constraints;
>even if it was an optimized interpreter.

<raised eyebrow>  Ten years ago, a 400MHz ARM processor would have been
fast, and it would have been running Python 1.5.2.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From sajmikins at gmail.com  Tue Jul  7 10:48:16 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 10:48:16 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <4A5344BE.2080006@sequans.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<4A5344BE.2080006@sequans.com>
Message-ID: <50f98a4c0907070748w39481ad9sed8ffba64b299dbc@mail.gmail.com>

On Tue, Jul 7, 2009 at 8:51 AM, Jean-Michel
Pichavant<jeanmichel at sequans.com> wrote:
> Steven D'Aprano wrote:
>>
>> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
>>
>>
>>>
>>> When people are fighting over things like `sense`, although sense may
>>> not be strictly wrong dictionary-wise, it smells of something burning...
>>>
>>
>> That would be my patience.
>>
>> I can't believe the direction this discussion has taken. Anybody sensible
>> would be saying "Oh wow, I've just learned a new meaning to the word, that's
>> great, I'm now less ignorant than I was a minute ago". But oh no, we mustn't
>> use a standard meaning to a word, heaven forbid we disturb people's
>> ignorance by teaching them something new.
>>
>> It's as simple as this: using `sense` as a variable name to record the
>> sense of a function is not a code smell, any more than using `flag` to
>> record a flag would be, or `sign` to record the sign of an object. If you
>> don't know the appropriate meanings of the words sense, flag or sign, learn
>> them, don't dumb down my language.
>>
>>
>
> Can't we just calm down ? I'm really sorry my ignorance started this thread,
> and my apologies go to Kj who's obviously more fluent in english than me.
> I've never used sense in that way before, nor I've seen used by others until
> now. However Kj is right, and my dictionary seems wrong (wordreference.com).
> I've searched through others dictionaries and find out this is actually
> applicable to functions. My bad.
>
> JM

Well met, sir.


From wuwei23 at gmail.com  Tue Jul  7 10:52:56 2009
From: wuwei23 at gmail.com (alex23)
Date: Tue, 7 Jul 2009 07:52:56 -0700 (PDT)
Subject: Remoting over SSH
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <f4a3012b-f462-425e-a081-cbf1b5f2a1fe@i4g2000prm.googlegroups.com>

On Jul 8, 12:46?am, Hussein B <hubaghd... at gmail.com> wrote:
> I want to perform commands on a remote server over SSH.
> What do I need?

Take a look at pexpect: http://pexpect.sourceforge.net/pexpect.html


From usernet at ilthio.net  Tue Jul  7 10:58:34 2009
From: usernet at ilthio.net (Tim Harig)
Date: Tue, 07 Jul 2009 14:58:34 GMT
Subject: Remoting over SSH
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <uoJ4m.6967$iz2.1440@nlpi070.nbdc.sbc.com>

On 2009-07-07, Hussein B <hubaghdadi at gmail.com> wrote:
> I want to perform commands on a remote server over SSH.
> What do I need?

catb.org/esr/faqs/smart-questions.html

There are many ways to remote using ssh.  If we know what you are trying to
do, maybe we could give you a better answer.  If you just want to open the
python interpreter interactively on another host you can do something like:

ssh -t user at host python

That will allow you send "commands" to the python interpeter.  You could
write a script and pipe it into the interpreter:

cat script.py | ssh -t user at host python

Maybe you want to open an ssh connection and send shell commands from a
python script.  You can do that using one of the popen2 functions:

http://docs.python.org/library/popen2.html


From nacim_bravo at agilent.com  Tue Jul  7 11:02:05 2009
From: nacim_bravo at agilent.com (nacim_bravo at agilent.com)
Date: Tue, 7 Jul 2009 09:02:05 -0600
Subject: Newbie needs help
In-Reply-To: <50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
	<50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>
Message-ID: <527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>

Hello Gurus,

Thank you for trying to help to my initial and not well written questions.  I will compile more detailed information and ask again.  Btw, I am giving a glimpse to: "How To Ask Questions The Smart Way".

nacim


-----Original Message-----
From: Simon Forman [mailto:sajmikins at gmail.com] 
Sent: Tuesday, July 07, 2009 7:19 AM
To: BRAVO,NACIM (A-Sonoma,ex1)
Cc: python-list at python.org
Subject: Re: Newbie needs help

On Mon, Jul 6, 2009 at 7:00 PM, <nacim_bravo at agilent.com> wrote:
> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment?
>
> Please let me know,
> nacim
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>

The answers to your first and third questions are, "yes" and "yes". :]
 (Generally speaking if something can be done by a computer it can be
done with python.)

As for your second question check out the "magnitude" package:

http://pypi.python.org/pypi/magnitude/   and
http://juanreyero.com/magnitude/

(That second link also has links to three other packages that deal
with units of measurement.)

Ii has units for the SI measurements, including volts and coulombs, so
you should be able to accomplish your goals with it.

The tricky thing is, as far as I can tell from the wikipedia entry
(http://en.wikipedia.org/wiki/Relative_static_permittivity),
"dielectric constant" seems to be a dimensionless number, i.e. C/C...
 I could be totally daft though.

HTH,
~Simon




From matt0177 at GMAIL.COM  Tue Jul  7 11:02:22 2009
From: matt0177 at GMAIL.COM (matt0177)
Date: Tue, 7 Jul 2009 08:02:22 -0700 (PDT)
Subject: Python Error from Apress book
In-Reply-To: <24364269.post@talk.nabble.com>
References: <24364269.post@talk.nabble.com>
Message-ID: <24374988.post@talk.nabble.com>


Adding the python before the command line didn't work at first, but upon
moving the files to the c:\python25 it worked like a champ. Thank you both
for the help. Very frustrating to run into stuff like this when you're first
trying to learn a knew language, it really throws off your momentum!
-- 
View this message in context: http://www.nabble.com/Python-Error-from-Apress-book-tp24364269p24374988.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From motoom at xs4all.nl  Tue Jul  7 11:05:32 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Tue, 07 Jul 2009 17:05:32 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <20090707135949.100950@gmx.net>
References: <20090707135949.100950@gmx.net>
Message-ID: <4A53643C.4020905@xs4all.nl>

Claus Hausberger wrote:

> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
> change that as I do not create those files myself. I have to read
> those files and convert the umlauts like ? to stuff like &oumol; as
> the text files should become html files.

umlaut-in.txt:
----
This file is contains data in the unicode
character set and is encoded with utf-8.
Viele R?hre. Macht spa?!  Ts?sch!


umlaut-in.txt hexdump:
----
000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e unicode..chara
000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and is
000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with utf
000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele R..hr
000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht spa..!
000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00  Ts..sch!.......


umlaut.py:
----
# -*- coding: utf-8 -*-
import codecs
text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
text=text.replace(u"?",u"oe")
text=text.replace(u"?",u"ss")
text=text.replace(u"?",u"ue")
of=open("umlaut-out.txt","w")
of.write(text)
of.close()


umlaut-out.txt:
----
This file is contains data in the unicode
character set and is encoded with utf-8.
Viele Roehre. Macht spass!  Tsuesch!


umlaut-out.txt hexdump:
----
000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e unicode...char
000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and is
000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with ut
000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele Roe
000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht spass
000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 !  Tsuesch!.....





-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html



From chengsoon.ong at inf.ethz.ch  Tue Jul  7 11:08:20 2009
From: chengsoon.ong at inf.ethz.ch (Cheng Soon Ong)
Date: Tue, 07 Jul 2009 17:08:20 +0200
Subject: automatic multiprocessing
Message-ID: <4A5364E4.4040607@inf.ethz.ch>

Hi all,

I'm trying to automate the use of multiprocessing when it is available. The 
setting I have is quite simple, with a for loop where the operations inside are 
independent of each other. Here's a bit of code. function_inputs is a list of 
dictionaries, each of which match the signature of function_handle.

     if multiprocessing_present:
         # Passing keyword arguments to map still doesn't work
         cpus = multiprocessing.Pool()
         function_outputs = cpus.map(function_handle, function_inputs)
     else:
         function_outputs = []
         for kwargs in function_inputs:
             cur_out = function_handle(**kwargs)
             function_outputs.append(cur_out)

Am I missing something here? I cannot seem to get map to pass on keyword arguments.

Thanks in advance,
Cheng Soon


From Scott.Daniels at Acm.Org  Tue Jul  7 11:11:27 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 07 Jul 2009 08:11:27 -0700
Subject: ISO library ref in printed form
In-Reply-To: <h2vcp9$66b$1@reader1.panix.com>
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <YrCdnen05dNx_s7XnZ2dnUVZ_sudnZ2d@pdx.net>

kj wrote:
> Does anyone know where I can buy the Python library reference in
> printed form?  (I'd rather not print the whole 1200+-page tome
> myself.)  I'm interested in both/either 2.6 and 3.0.

Personally, I'd get the new Beazley's Python Essential Reference,
which is due out "real soon now," and then use the provided docs
as a addon.  Also consider grabbing Gruet's "Python Quick Reference"
page.  When I was working in a printer site I printed the color
version of Gruet's page two-sided; it was neither too bulky nor
too sketchy for my needs (and he uses color to distinguish
version-to-version changes).
     http://rgruet.free.fr/
Sadly, I no longer work there, so my copy is gone. :-(

--Scott David Daniels
Scott.Daniels at Acm.Org


From tn.pablo at gmail.com  Tue Jul  7 11:12:38 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Tue, 7 Jul 2009 10:12:38 -0500
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com> 
	<50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com> 
	<527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>
Message-ID: <fdd00b510907070812y26e63ba0l75aff6d739738da8@mail.gmail.com>

On Tue, Jul 7, 2009 at 10:02, <nacim_bravo at agilent.com> wrote:
> Hello Gurus,
>
> Thank you for trying to help to my initial and not well written questions. ?I will compile more detailed information and ask again. ?Btw, I am giving a glimpse to: "How To Ask Questions The Smart Way".
>
> nacim

Give this one a try too: http://www.mikeash.com/getting_answers.html
It doesn't talk down to you...as much :P


-- 
Pablo Torres N.


From aahz at pythoncraft.com  Tue Jul  7 11:29:28 2009
From: aahz at pythoncraft.com (Aahz)
Date: 7 Jul 2009 08:29:28 -0700
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <h2vpko$jpk$1@panix3.panix.com>

In article <h2vcp9$66b$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>Does anyone know where I can buy the Python library reference in
>printed form?  (I'd rather not print the whole 1200+-page tome
>myself.)  I'm interested in both/either 2.6 and 3.0.

There used to be one for Python 2.1, but I can't tell whether it's ever
been updated because the website isn't responding:

http://wiki.python.org/moin/ReferenceBooks
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From davea at ieee.org  Tue Jul  7 11:44:44 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 11:44:44 -0400
Subject: Python Error from Apress book
In-Reply-To: <24374988.post@talk.nabble.com>
References: <24364269.post@talk.nabble.com> <24374988.post@talk.nabble.com>
Message-ID: <4A536D6C.4010308@ieee.org>

matt0177 wrote:
> Adding the python before the command line didn't work at first, but upon
> moving the files to the c:\python25 it worked like a champ. Thank you both
> for the help. Very frustrating to run into stuff like this when you're first
> trying to learn a knew language, it really throws off your momentum!
>   
I'm glad you got things working.  But you really shouldn't need to add 
your own files to the installation directory.  What you need is 
straightforward, but the details are Windows specific

The following is all at the command prompt, not inside Python.

You have a PATH environment variable, with various directories on it.  
Type it out using the PATH command.  Pick a location on it, and add a 
batch file we'll write below.  It's also possible to add a new directory 
to the PATH, using the control panel.  Normally, the first thing I do on 
a new machine is add two directories to the PATH, perhaps  c:\bin  and 
c:\bat.  The former is for the simple one-file utilities you accumulate 
over the years, and the latter is for batch files.  If you want to 
pursue this, let me know, and I'll give details.

Now that you've picked a location for your batch file, let's create it, 
calling it   Python25.bat   You could just call it Python.bat, but this 
way, you can have more than one Python installed, and choose between them.

The contents of Python25.bat are a single line:

@c:\python25\python.exe  %*

The leading @ says we don't wan the line echoed to the screen.  If 
you're unsure of yourself, you can leave it off till everything works 
well, then add it in.  The %* says to copy all the arguments you pass 
the batch file into the executable.

Once this batch file is stored in your PATH, you can just type something 
like:

      python25  myscript.py   arg1 arg2

or, to run the interpreter itself,
     python25

DaveA



From fetchinson at googlemail.com  Tue Jul  7 12:14:48 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Tue, 7 Jul 2009 09:14:48 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <4a531512$0$9355$426a74cc@news.free.fr>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
	<4a531512$0$9355$426a74cc@news.free.fr>
Message-ID: <fbe2e2100907070914m3c1f81d6i9b5165787263d1d2@mail.gmail.com>

> (snip)
>> and my point is that users
>> are most of time correct when they assume that something will work the
>> same way as in C.
>
> Oh, really ? They would surely be wrong if they'd expect the for loop to
> have any similarity with a C for loop, or - a *very* common error - if
> they'd expect assignment to work the same way as in C.

Yes, really. I wrote ".... most of the time ....." and not "all the time".

>> So I'd think that putting a warning in a FAQ or a Python Gotchas list
>> about ++n would be very useful for many users.
>
> Might eventually be useful, but I can't hardly recall of more than a
> couple threads on this topic in 8+ years.

I'm happy we agree.

Cheers,
Daniel

-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From sajmikins at gmail.com  Tue Jul  7 12:16:18 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 09:16:18 -0700 (PDT)
Subject: automatic multiprocessing
References: mailman.2782.1246980030.8015.python-list@python.org
Message-ID: <f72b0ed4-406d-4f9f-b629-0914143f6673@r33g2000yqn.googlegroups.com>

On Jul 7, 11:08?am, Cheng Soon Ong <chengsoon.... at inf.ethz.ch> wrote:
> Hi all,
>
> I'm trying to automate the use of multiprocessing when it is available. The
> setting I have is quite simple, with a for loop where the operations inside are
> independent of each other. Here's a bit of code. function_inputs is a list of
> dictionaries, each of which match the signature of function_handle.
>
> ? ? ?if multiprocessing_present:
> ? ? ? ? ?# Passing keyword arguments to map still doesn't work
> ? ? ? ? ?cpus = multiprocessing.Pool()
> ? ? ? ? ?function_outputs = cpus.map(function_handle, function_inputs)
> ? ? ?else:
> ? ? ? ? ?function_outputs = []
> ? ? ? ? ?for kwargs in function_inputs:
> ? ? ? ? ? ? ?cur_out = function_handle(**kwargs)
> ? ? ? ? ? ? ?function_outputs.append(cur_out)
>
> Am I missing something here? I cannot seem to get map to pass on keyword arguments.
>
> Thanks in advance,
> Cheng Soon

Pool.map() doesn't handle "**dict" keyword argument notation
automatically.  You could use a wrapper function like so:

cpus = multiprocessing.Pool()
def f(kwargs):
    return function_handle(**kwargs)
function_outputs = cpus.map(f, function_inputs)

(Note that f() could be defined outside the if statement if you're
going to use it often.)

HTH,
~Simon


From fetchinson at googlemail.com  Tue Jul  7 12:23:30 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Tue, 7 Jul 2009 09:23:30 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <4a531560$0$9355$426a74cc@news.free.fr>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
	<mailman.2754.1246945937.8015.python-list@python.org>
	<4a531560$0$9355$426a74cc@news.free.fr>
Message-ID: <fbe2e2100907070923n3caee67am2823d3b92209d6e4@mail.gmail.com>

>>>> Yes, there are plenty of languages other than Java and C, but the
>>>> influence of C is admittedly huge in Python. Why do you think loops
>>>> are called "for", conditionals "if" or "while", functions return via
>>>> "return", loops terminate via "break" and keep going via "continue"
>>>> and why is comparison written as "==", etc, etc? All of these are
>>>> coming from C (or an even earlier language) and my point is that users
>>> 	for, if, and return were common keywords in FORTRAN.
>>>
>>> 	Not to mention BASIC
>>>
>>> 	Both of which predate C
>>
>> Yes, hence my comment above, ".... coming from C (or an even earlier
>> language) ......".
>
>
> Mmm... Should we then claim that "the influence of FORTRAN is admittedly
> huge in Python" ?-)

Hmmmm, your comments reached a level of pedanticism beyond which I can
not follow :)
Seriously, ask Guido about the influence of C vs. fortran. Somewhere
you can find him quoted as saying that python was originally intended
to "bridge the gap between the shell and C". I've never heard him talk
about fortran.

But this academic discussion is honestly a little pointless. The OP
was referring to a expectation, coming from C, that is not fulfilled
in python. What's wrong with mentioning it somewhere for the sake of
helping C programmers?

Cheers,
Daniel


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From fetchinson at googlemail.com  Tue Jul  7 12:29:51 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Tue, 7 Jul 2009 09:29:51 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <4a531512$0$9355$426a74cc@news.free.fr>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
	<4a531512$0$9355$426a74cc@news.free.fr>
Message-ID: <fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>

>> and my point is that users
>> are most of time correct when they assume that something will work the
>> same way as in C.
>
> Oh, really ? They would surely be wrong if they'd expect the for loop to
> have any similarity with a C for loop, or - a *very* common error - if
> they'd expect assignment to work the same way as in C.

By the way, assignments in conditionals. Guido explicitly referred to
C when he forbade assignment in conditionals, citing common
typos/errors in C code such as if( x = 5 ){ .... } instead of if( x ==
5 ){ ..... }. So even he realized that warning people about different
usage in python and C is a good thing. Expectations from C work
sometimes, and sometimes they don't. In latter case a little warning
is useful.

Cheers,
Daniel

>> So I'd think that putting a warning in a FAQ or a Python Gotchas list
>> about ++n would be very useful for many users.
>
> Might eventually be useful, but I can't hardly recall of more than a
> couple threads on this topic in 8+ years.



-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From nagle at animats.com  Tue Jul  7 12:40:15 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 07 Jul 2009 09:40:15 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a5310e7$0$31327$9b4e6d93@newsspool4.arcor-online.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
	<4a52eb5f$0$1663$742ec2ed@news.sonic.net>
	<4a5310e7$0$31327$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <4a537a11$0$1672$742ec2ed@news.sonic.net>

Stefan Behnel wrote:
> John Nagle wrote:
>>     I have a small web crawler robust enough to parse
>> real-world HTML, which can be appallingly bad.  I currently use
>> an extra-robust version of BeautifulSoup, and even that sometimes
>> blows up.  So I'm very interested in a new Python parser which supposedly
>> handles bad HTML in the same way browsers do.  But if it's slower
>> than BeautifulSoup, there's a problem.
> 
> Well, if performance matters in any way, you can always use lxml's
> blazingly fast parser first, possibly trying a couple of different
> configurations, and only if all fail, fall back to running html5lib over
> the same input. 

    Detecting "fail" is difficult.  A common problem is badly terminated
comments which eat most of the document if you follow the spec.  The
document seems to parse correctly, but most of it is missing.  The
HTML 5 spec actually covers things like

	<!This is a bogus SGML directive>

and treats it as a bogus comment.  (That's because HTML 5 doesn't
include general SGML; the only directive recognized is DOCTYPE.
Anything else after "<!" is treated as a token-level error.)

    So using an agreed-upon parsing method, in the form of html5lib,
is desirable, in that it should mimic browser behavior.

					John Nagle


From stefan_ml at behnel.de  Tue Jul  7 12:50:48 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 18:50:48 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <mailman.2780.1246979137.8015.python-list@python.org>
References: <20090707135949.100950@gmx.net>
	<mailman.2780.1246979137.8015.python-list@python.org>
Message-ID: <4a537ce8$0$30220$9b4e6d93@newsspool1.arcor-online.net>

Michiel Overtoom schrob:
> Viele R?hre. Macht spa?!  Ts?sch!

LOL! :)

Stefan


From dana_at_work at yahoo.com  Tue Jul  7 13:05:07 2009
From: dana_at_work at yahoo.com (dana)
Date: Tue, 7 Jul 2009 10:05:07 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
Message-ID: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>

I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
modules together. Although I don't have Python 2.5, I've been informed
the DBI module has been deprecated at 2.5. A few questions:

1) Although deprecated, will it work at all in 2.5? Does the fact that
it is deprecrated mean it has been removed entirely, or does Python
2.5 simply issuing a warning?

2) What do I use in place of DBI for my Python 2.4. scripts that
import modules DBI and ODBC together. I don't use DBI directly. It was
simply a dependency for the ODBC module as best I knew.

Thanks.

Dana


From python at mrabarnett.plus.com  Tue Jul  7 13:10:27 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 18:10:27 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<mailman.2746.1246935242.8015.python-list@python.org>	<4a531512$0$9355$426a74cc@news.free.fr>
	<fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>
Message-ID: <4A538183.9020009@mrabarnett.plus.com>

Daniel Fetchinson wrote:
>>> and my point is that users
>>> are most of time correct when they assume that something will work the
>>> same way as in C.
>> Oh, really ? They would surely be wrong if they'd expect the for loop to
>> have any similarity with a C for loop, or - a *very* common error - if
>> they'd expect assignment to work the same way as in C.
> 
> By the way, assignments in conditionals. Guido explicitly referred to
> C when he forbade assignment in conditionals, citing common
> typos/errors in C code such as if( x = 5 ){ .... } instead of if( x ==
> 5 ){ ..... }. So even he realized that warning people about different
> usage in python and C is a good thing. Expectations from C work
> sometimes, and sometimes they don't. In latter case a little warning
> is useful.
> 
I wonder whether the problem with assignment in conditionals in C is due
to the assignment operator being "=". If it was ":=", would the error
still occur?


From douglas.packard at gmail.com  Tue Jul  7 13:34:17 2009
From: douglas.packard at gmail.com (weforgottenuno)
Date: Tue, 7 Jul 2009 10:34:17 -0700 (PDT)
Subject: Unable to get Tkinter menubar to appear under OS X
References: <3737fd18-4973-4cc3-914d-fbdefdbbb8a7@t10g2000vbg.googlegroups.com>
Message-ID: <6a9b0831-ce2e-417b-ab4b-419629d0a25d@u16g2000pru.googlegroups.com>

I'm having the same problem, though I am just using the pre-installed
python and tkinter versions that are on my OS X 10.5 computer, I did
not install them on my own. Any advice?

-Doug

On Jun 24, 9:22?am, Eric Winter <elwin... at verizon.net> wrote:
> Hi all. I've googled this issue several times and come up dry. Here's
> the situation:
>
> I have a X-windows build of Tkinter for Python built on an OS X
> machine (10.4 or 10.5, same issue). This is not the Aqua version of
> Tk, but Tk built from source using X-Window support. I also use a from-
> source build of Python, not the system Python. I don't like this
> arrangement, but project requirements (allegedly) dictate this
> approach.
>
> When I run any application using that copy of Tkinter and that copy of
> Python, everything seems to work fine except menus - the code which
> creates the menus runs, but no menus appear, either in the window or
> at the top of the screen.
>
> Am I required to use the Aqua version of Tk on OS X? If not, do I need
> to do something special on OS X when I built Tk and/or Python? Any
> hints here would be greatly appreciated.
>
> Thanks,
> Eric Winter
> Fermi Science Support Center
> NASA Goddard Space Flight Center



From piet at cs.uu.nl  Tue Jul  7 13:38:59 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 19:38:59 +0200
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com> <h2vn6l$klq$1@panix3.panix.com>
Message-ID: <m2eisscs0c.fsf@cs.uu.nl>

>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:

>A> In article <85ljn0ej4h.fsf at agentultra.com>,
>A> J Kenneth King  <james at agentultra.com> wrote:
>>> 
>>> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>>> device are already limited; running your program on top of an embedded
>>> Python interpreter would only be adding pressure to the constraints;
>>> even if it was an optimized interpreter.

>A> <raised eyebrow>  Ten years ago, a 400MHz ARM processor would have been
>A> fast, and it would have been running Python 1.5.2.

My first Python experience at home was on a 40MHz 80486 (Python 1.5.2 I
think). It was a bit slow :=(
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From hannarosie at gmail.com  Tue Jul  7 13:46:47 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Tue, 7 Jul 2009 10:46:47 -0700
Subject: Write matrix to text file
Message-ID: <564970db0907071046o60e927dao21cc0557f1fa2903@mail.gmail.com>

Hi,

I'm working with both python and matlab at the moment and I was wondering if
there is an efficient way to take a 2-D array (of 1s and 0s) in python and
write it to a text file such that matlab will be able to create a sparse
matrix from it later.

Thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/f0c1c374/attachment.html>

From stefan_ml at behnel.de  Tue Jul  7 13:48:32 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 19:48:32 +0200
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2rnoe$26s$5@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <4a538a71$0$30236$9b4e6d93@newsspool1.arcor-online.net>

Lawrence D'Oliveiro wrote:
> I wonder how many people have been tripped up by the fact that
> 
>     ++n
> 
> and
> 
>     --n
> 
> fail silently for numeric-valued n.

I doubt that there are many. Plus, you misspelled them from the more obvious

	n++

and

	n--

which *do* fail with a SyntaxError. I think I faintly remember trying those
in my early Python days and immediately went for "+=" when I saw them fail
(as I had expected).

Stefan


From robert.oschler at gmail.com  Tue Jul  7 14:01:17 2009
From: robert.oschler at gmail.com (roschler)
Date: Tue, 7 Jul 2009 11:01:17 -0700 (PDT)
Subject: Embedded Python : Why does thread lock here?
Message-ID: <00e8b4e8-5386-4f3d-b900-ab1ba41294f2@q40g2000prh.googlegroups.com>

I have the Python Intepreter embedded in a Delphi (Object Pascal)
program.  In the Python script shown below, I have a module that
creates a thread object and starts it.  The thread's run() call calls
a function called deleteOutputVariables() declared at the module
level.  In my code's first incarnation the thread's run() call would
deadlock when trying to call the deleteOutputVariables() function
declared at Module level.  I would never see the statement
"(deleteOutputVariables) Top of Call" printed to the screen.  I now
know that I must periodically call join() with a very fast time-out to
keep Python threads happy, and that solved the problem.  However I am
curious as to why it deadlocked at the deleteOutputVariables() call?
Is it because deleteOutputVariables() is declared at the module level
or because that function deletes module level variables?  If so why?

The code with the relevant parts excerpted is shown below, hopefully
the indents hold up.

Thanks,
Robert

----------------------------

# MODULE: PythonThreadTest.py

# FUNCTION: Delete the variables given in the list.
def deleteOutputVariables(theModule, theOutputVariablesListOfNames):
    try:
        print "(deleteOutputVariables) Top of call."
        for theOutputVariableName in theOutputVariablesListOfNames:
            if theModule.__dict__.has_key(theOutputVariableName):
                print "(Python::deleteOutputVariables) Deleting the
Output Variable named " + theOutputVariableName
                del theModule.__dict__[theOutputVariableName]
    except:
        print "(deleteOutputVariables) Exception occurred."

# Import needed system modules
import sys, os
from threading import Thread

# ----------------- BEGIN: THREAD class to execute robodanceCommand()
class threadRun(Thread):
    def __init__ (self, theJobID = None):
        Thread.__init__(self)
        self.jobCompleted = False
    # def: __init__
    def run(self):
        try:
        	# NOTE ---> This is where the thread locks if I don't call
join(0.001) in
        	#  my DELPHI (not Python) loop that waits on the thread to
complete.  Once
        	#  theNewThread.join() is called, execution resumes in
        	#  deleteOutputVariables() and the thread completes.
            deleteOutputVariables(Test_PYTHON, ["PyOut1"])

            # Let others know we are done.
            self.jobCompleted = True
        except Exception, exc:
            self.exceptionCaught = exc
            # Let others know we are done.
            self.jobCompleted = True
            print("(Python::threadRun) Exception occurred.")
        # end: try
    # def: run()
# ----------------- END: THREAD to execute robodanceCommand()

theNewThread = None
theNewThread = threadRun("TestThread")
theNewThread.start()


From pdpinheiro at gmail.com  Tue Jul  7 14:01:33 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:01:33 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>

On Jul 7, 2:16?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Mon, 06 Jul 2009 16:43:43 +0100, Tim Rowe wrote:
> > 2009/7/4 kj <no.em... at please.post>:
>
> >> Precisely. ?As I've stated elsewhere, this is an internal helper
> >> function, to be called only a few times under very well-specified
> >> conditions. ?The assert statements checks that these conditions are as
> >> intended. ?I.e. they are checks against the module writer's programming
> >> errors.
>
> > Good for you. I'm convinced that you have used the assertion
> > appropriately, and the fact that so many here are unable to see that
> > looks to me like a good case for teaching the right use of assertions.
> > For what it's worth, I read assertions at the beginning of a procedure
> > as part of the specification of the procedure, and I use them there in
> > order to document the procedure. An assertion in that position is for me
> > a statement to the user of the procedure "it's your responsibility to
> > make sure that you never call this procedure in such a way as to violate
> > these conditions". They're part of a contract, as somebody (maybe you)
> > pointed out.
>
> > As somebody who works in the safety-critical domain, it's refreshing to
> > see somebody teaching students to think about the circumstances in which
> > a procedure can legitimately be called. The hostility you've received to
> > that idea is saddening, and indicative of why there's so much buggy
> > software out there.
>
> LOL.
>
> Maybe the reason for "so much buggy software" is that people
> inappropriately use assert, thus changing the behaviour of code depending
> on whether it is run with the -O flag or not.
>
> I don't know what "hostility" you're seeing. The only hostility I'm
> seeing is from the OP, which is bizarre considering that he asked for
> advice and we gave it. What I see is a bunch of people concerned that the
> OP is teaching novices a bad habit, namely, using assert for error
> checking. He claims -- angrily and over and over again -- that in his
> code, the assertions should never fail. Great. Good for him for knowing
> when to use assert. (...)

But he doesn't.

He asserts:
    assert lo < hi
but then compares:
    sense = cmp(func(hi), func(lo))

sense can't ever be anything other than 1. I actually find it amusing
that this threat got to 50 posts of raving discussion about assertions
without anyone spotting that.

Personally, I think the code is an unreadable mess, but that's mostly
because of all the micro optimizations, not the generality of it.
Here's my unoptimized, but still equally generic, version:

def _binary_search(lo, hi, func, target, epsilon):
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    guess = (lo + hi) / 2.
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if func(guess) > target:
            hi = guess
        elif func(guess) < target:
            lo = guess
        elif lo == hi:
            return None
    return guess

This is a newbie course, right? A while True loop might be faster, but
it's all sorts of wrong for teaching newbies. Likewise, calculating a
midpoint as mid = (hi + lo) * .5 is an aberration in a beginner
environment. You want your students asking why you're calculating an
average, not asking why you're multiplying by 0.5. In the same vein, I
have no words for your target_plus/target_minus cleverness.

The right way to go about it, IMO, is to give them my version, let
them digest it, make all the necessary changes to it to turn it into
your (faster) version. Present benchmarks for both, then let the
readability/performance trade-off sink in. What you achieve with this
exercise is that, instead of making your students think "I have to
read that crud!?", they'll respect that ugly code is often the result
of eking out every last drop of performance from a program as you
possibly can.


From inky788 at gmail.com  Tue Jul  7 14:01:45 2009
From: inky788 at gmail.com (Inky 788)
Date: Tue, 7 Jul 2009 11:01:45 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com> 
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net> 
	<mailman.2759.1246954003.8015.python-list@python.org>
Message-ID: <59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>

On Jul 7, 4:06?am, Chris Withers <ch... at simplistix.co.uk> wrote:
> David Lyon wrote:
>
> > What hasn't happened is enough testing of pypi packages and installing
> > with setuptools/pip/enstall from pypi.
>
> What needs testing?
>
> More important for me is which of these has the most active development
> community. How do we judge that?

Currently, distutils itself is being actively developed. More info
about this here: http://tarekziade.wordpress.com/

My (albeit anonymous) advice is: use distutils. Manually download
packages as-needed from PyPI and install manually using standard
distutils.

Read more about distutils here http://wiki.python.org/moin/Distutils
and of course in the Python docs.

If you want to contribute, my first guess would be that Tarek could
use help writing tests (but I don't know what distutils coverage looks
like at the moment).

When Tarek says, "For package installation that takes care of
dependencies, uninstall, etc., use $tool", then I'll start using
$tool. Until then, it's just straight distutils for me.


From http  Tue Jul  7 14:06:59 2009
From: http (Paul Rubin)
Date: 07 Jul 2009 11:06:59 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
Message-ID: <7xab3gz7ss.fsf@ruckus.brouhaha.com>

pdpi <pdpinheiro at gmail.com> writes:
> Personally, I think the code is an unreadable mess, but that's mostly
> because of all the micro optimizations, not the generality of it.
> Here's my unoptimized, but still equally generic, version:

That version doesn't use "sense" inside the binary search, i.e. it
relies on the function being monotonically increasing.


From andreengels at gmail.com  Tue Jul  7 14:26:45 2009
From: andreengels at gmail.com (Andre Engels)
Date: Tue, 7 Jul 2009 20:26:45 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
Message-ID: <6faf39c90907071126o5c774a79h4de2921fb3af205a@mail.gmail.com>

On Tue, Jul 7, 2009 at 8:01 PM, pdpi<pdpinheiro at gmail.com> wrote:

> He asserts:
> ? ?assert lo < hi
> but then compares:
> ? ?sense = cmp(func(hi), func(lo))
>
> sense can't ever be anything other than 1.

It can - there is no necessity that func is monotonically increasing.

-- 
Andr? Engels, andreengels at gmail.com


From pdpinheiro at gmail.com  Tue Jul  7 14:30:42 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:30:42 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> 
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<mailman.2789.1246991214.8015.python-list@python.org>
Message-ID: <bdcef469-2d7e-4a7f-bfe5-2a2bcf9a5b91@a36g2000yqc.googlegroups.com>

On Jul 7, 7:26?pm, Andre Engels <andreeng... at gmail.com> wrote:
> On Tue, Jul 7, 2009 at 8:01 PM, pdpi<pdpinhe... at gmail.com> wrote:
> > He asserts:
> > ? ?assert lo < hi
> > but then compares:
> > ? ?sense = cmp(func(hi), func(lo))
>
> > sense can't ever be anything other than 1.
>
> It can - there is no necessity that func is monotonically increasing.
>
> --
> Andr? Engels, andreeng... at gmail.com

Yes, I realized that as I was walking home.

In other news, some of you may be interested in my seminar in advanced
foot-in-mouth placement.


From pdpinheiro at gmail.com  Tue Jul  7 14:31:39 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:31:39 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
Message-ID: <1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>

On Jul 7, 7:06?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> pdpi <pdpinhe... at gmail.com> writes:
> > Personally, I think the code is an unreadable mess, but that's mostly
> > because of all the micro optimizations, not the generality of it.
> > Here's my unoptimized, but still equally generic, version:
>
> That version doesn't use "sense" inside the binary search, i.e. it
> relies on the function being monotonically increasing.

You're right, make that:

def _binary_search(lo, hi, func, target, epsilon):
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    guess = (lo + hi) / 2.
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if sense * func(guess) > target:
            hi = guess
        elif sense * func(guess) < target:
            lo = guess
        elif lo == hi:
            return None
    return guess

Seems I had a serious brain cramp while posting that...


From pdpinheiro at gmail.com  Tue Jul  7 14:51:59 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:51:59 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
	<1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>
Message-ID: <1f09e856-bd04-4d27-bf51-5d67953a7e13@y7g2000yqa.googlegroups.com>

On Jul 7, 7:31?pm, pdpi <pdpinhe... at gmail.com> wrote:
> On Jul 7, 7:06?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>
> > pdpi <pdpinhe... at gmail.com> writes:
> > > Personally, I think the code is an unreadable mess, but that's mostly
> > > because of all the micro optimizations, not the generality of it.
> > > Here's my unoptimized, but still equally generic, version:
>
> > That version doesn't use "sense" inside the binary search, i.e. it
> > relies on the function being monotonically increasing.
>
> You're right, make that:
>
> def _binary_search(lo, hi, func, target, epsilon):
> ? ? sense = cmp(func(hi), func(lo))
> ? ? if sense == 0:
> ? ? ? ? return None
> ? ? guess = (lo + hi) / 2.
> ? ? while abs(func(guess) - target) > epsilon:
> ? ? ? ? guess = (lo + hi) / 2.
> ? ? ? ? if sense * func(guess) > target:
> ? ? ? ? ? ? hi = guess
> ? ? ? ? elif sense * func(guess) < target:
> ? ? ? ? ? ? lo = guess
> ? ? ? ? elif lo == hi:
> ? ? ? ? ? ? return None
> ? ? return guess
>
> Seems I had a serious brain cramp while posting that...

Actually, scratch that.

def _binary_search(lo, hi, func, target, epsilon):
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    guess = (lo + hi) / 2.
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if sense * func(guess) > sense * target:
            hi = guess
        elif sense * func(guess) < sense * target:
            lo = guess
        elif lo == hi:
            return None
    return guess


From CHausberger at gmx.de  Tue Jul  7 15:00:46 2009
From: CHausberger at gmx.de (Claus Hausberger)
Date: Tue, 07 Jul 2009 21:00:46 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <4A53643C.4020905@xs4all.nl>
References: <20090707135949.100950@gmx.net> <4A53643C.4020905@xs4all.nl>
Message-ID: <20090707190046.152740@gmx.net>

Thanks a lot. Now I am one step further but I get another strange error:

Traceback (most recent call last):
  File "./read.py", line 12, in <module>
    of.write(text)
UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in position 0: ordinal not in range(128)

according to google ufeff has something to do with byte order.

I use an Linux system, maybe this helps to find the error.

Claus

> Claus Hausberger wrote:
> 
> > I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
> > change that as I do not create those files myself. I have to read
> > those files and convert the umlauts like ? to stuff like &oumol; as
> > the text files should become html files.
> 
> umlaut-in.txt:
> ----
> This file is contains data in the unicode
> character set and is encoded with utf-8.
> Viele R?hre. Macht spa?!  Ts?sch!
> 
> 
> umlaut-in.txt hexdump:
> ----
> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e unicode..chara
> 000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and is
> 000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with utf
> 000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele R..hr
> 000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht spa..!
> 000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00  Ts..sch!.......
> 
> 
> umlaut.py:
> ----
> # -*- coding: utf-8 -*-
> import codecs
> text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
> text=text.replace(u"?",u"oe")
> text=text.replace(u"?",u"ss")
> text=text.replace(u"?",u"ue")
> of=open("umlaut-out.txt","w")
> of.write(text)
> of.close()
> 
> 
> umlaut-out.txt:
> ----
> This file is contains data in the unicode
> character set and is encoded with utf-8.
> Viele Roehre. Macht spass!  Tsuesch!
> 
> 
> umlaut-out.txt hexdump:
> ----
> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e unicode...char
> 000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and is
> 000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with ut
> 000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele Roe
> 000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht spass
> 000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 !  Tsuesch!.....
> 
> 
> 
> 
> 
> -- 
> "The ability of the OSS process to collect and harness
> the collective IQ of thousands of individuals across
> the Internet is simply amazing." - Vinod Valloppillil
> http://www.catb.org/~esr/halloween/halloween4.html

-- 
Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
f?r nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


From davea at ieee.org  Tue Jul  7 15:04:27 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 15:04:27 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
Message-ID: <4A539C3B.3040508@ieee.org>

pdpi wrote:
> On Jul 7, 2:16 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>   
>> On Mon, 06 Jul 2009 16:43:43 +0100, Tim Rowe wrote:
>>     
>>> 2009/7/4 kj <no.em... at please.post>:
>>>       
>>>> Precisely.  As I've stated elsewhere, this is an internal helper
>>>> function, to be called only a few times under very well-specified
>>>> conditions.  The assert statements checks that these conditions are as
>>>> intended.  I.e. they are checks against the module writer's programming
>>>> errors.
>>>>         
>>> Good for you. I'm convinced that you have used the assertion
>>> appropriately, and the fact that so many here are unable to see that
>>> looks to me like a good case for teaching the right use of assertions.
>>> For what it's worth, I read assertions at the beginning of a procedure
>>> as part of the specification of the procedure, and I use them there in
>>> order to document the procedure. An assertion in that position is for me
>>> a statement to the user of the procedure "it's your responsibility to
>>> make sure that you never call this procedure in such a way as to violate
>>> these conditions". They're part of a contract, as somebody (maybe you)
>>> pointed out.
>>>       
>>> As somebody who works in the safety-critical domain, it's refreshing to
>>> see somebody teaching students to think about the circumstances in which
>>> a procedure can legitimately be called. The hostility you've received to
>>> that idea is saddening, and indicative of why there's so much buggy
>>> software out there.
>>>       
>> LOL.
>>
>> Maybe the reason for "so much buggy software" is that people
>> inappropriately use assert, thus changing the behaviour of code depending
>> on whether it is run with the -O flag or not.
>>
>> I don't know what "hostility" you're seeing. The only hostility I'm
>> seeing is from the OP, which is bizarre considering that he asked for
>> advice and we gave it. What I see is a bunch of people concerned that the
>> OP is teaching novices a bad habit, namely, using assert for error
>> checking. He claims -- angrily and over and over again -- that in his
>> code, the assertions should never fail. Great. Good for him for knowing
>> when to use assert. (...)
>>     
>
> But he doesn't.
>
> He asserts:
>     assert lo < hi
> but then compares:
>     sense =mp(func(hi), func(lo))
>
> sense can't ever be anything other than 1. I actually find it amusing
> that this threat got to 50 posts of raving discussion about assertions
> without anyone spotting that.
>
>   
That's because the assert and the comparison are unrelated to each 
other.  If the function is monotonically decreasing, then by definition 
lo<hi would guarantee that  func(lo)>= func(hi), which would yield a 
sense of 0 or -1.

Trivial example of monotonically decreasing:
    def func(inp):
         return 53.0 - inp

> Personally, I think the code is an unreadable mess, but that's mostly
> because of all the micro optimizations, not the generality of it.
> Here's my unoptimized, but still equally generic, version:
>
> def _binary_search(lo, hi, func, target, epsilon):
>     sense =mp(func(hi), func(lo))
>     if sense =0:
>         return None
>     guess =lo + hi) / 2.
>     while abs(func(guess) - target) > epsilon:
>         guess =lo + hi) / 2.
>         if func(guess) > target:
>             hi =uess
>         elif func(guess) < target:
>             lo =uess
>         elif lo =hi:
>             return None
>     return guess
>
>   
And of course your clarified function will fail if the func is 
monotonically decreasing.

I still think that rather than using sense in the loop, one should 
simply swap lo and hi, and continue.
> This is a newbie course, right? A while True loop might be faster, but
> it's all sorts of wrong for teaching newbies. Likewise, calculating a
> midpoint as mid =hi + lo) * .5 is an aberration in a beginner
> environment. You want your students asking why you're calculating an
> average, not asking why you're multiplying by 0.5. In the same vein, I
> have no words for your target_plus/target_minus cleverness.
>
> The right way to go about it, IMO, is to give them my version, let
> them digest it, make all the necessary changes to it to turn it into
> your (faster) version. Present benchmarks for both, then let the
> readability/performance trade-off sink in. What you achieve with this
> exercise is that, instead of making your students think "I have to
> read that crud!?", they'll respect that ugly code is often the result
> of eking out every last drop of performance from a program as you
> possibly can.
>
>   
(untested)

def _binary_search(lo, hi, func, target, epsilon):
    """ lo, hi  are floats representing the desired range of input values to func()
        func() is a function that takes a float argument, and returns a float result
        target is the desired result value of func()
        epsilon is the allowable error compared to target.  If set too small, this function will fail by returning None
        precondition:  func is monotonic over the range of floating point inputs from lo to hi """
        return a float value between lo and hi (inclusive) which yields approximately target
    if func(lo) > func(hi):
        lo, hi = hi, lo
    if not (func(lo) <= target <= func(hi)):
        return None                     #function doesn't have target value within the input range
    guess = lo
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if func(guess) > target:
            hi = guess
        elif func(guess) < target:
            lo = guess
        elif lo == hi:
            return None            #function is too steep to have a value within epsilon
    return guess

The reason for the "too steep" condition is that with a finite 
resolution for 'guess'  epsilon could be enough smaller than target as 
to make a result impossible.  For example, if the slope is 45 degrees, 
this happens when epsilon is about 2**51 smaller.




From pdpinheiro at gmail.com  Tue Jul  7 15:10:59 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 12:10:59 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<mailman.2791.1246993486.8015.python-list@python.org>
Message-ID: <51f115a9-3e03-49f8-a340-4969133488cf@t33g2000yqe.googlegroups.com>

On Jul 7, 8:04?pm, Dave Angel <da... at ieee.org> wrote:
> And of course your clarified function will fail if the func is
> monotonically decreasing.

yeah, I eventually realized that and corrected it... And the assert()/
cmp() confusion too. I blame lack of sleep.

The whole sign/sense thing left a really bad taste in my mouth,
though, and the swapping lo and hi suggestion of yours seems like the
neatest solution presented.


From davea at ieee.org  Tue Jul  7 15:17:42 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 15:17:42 -0400
Subject: Python Error from Apress book
In-Reply-To: <8e2cbd660907071048p3a7c3bf9r22026712bf9bc3e4@mail.gmail.com>
References: <24364269.post@talk.nabble.com> <24374988.post@talk.nabble.com>	
	<4A536D6C.4010308@ieee.org>
	<8e2cbd660907071048p3a7c3bf9r22026712bf9bc3e4@mail.gmail.com>
Message-ID: <4A539F56.9070109@ieee.org>

Matthew Edmondson wrote:
> Thanks a ton for the help. At first adding the path didn't work, but after
> restarting my computer, ran like a champ :)
>
> Hopefully I can get decent with this language one day!
>
>   
All you needed was to restart the DOS-box (Command Prompt), after you 
did the control-panel thing.  Those changes don't affect currently 
running processes.

.
By the way, those "standalone executables" could very well be python 
scripts.  Except for input redirection, all my single-file scripts work 
fine stored there.  And if you add  .py and .pyw to the PATHEXT 
environment variable, you can run them without extension, so they're 
pretty much interchangeable with .exe files.

So I have a script called digest.py, and I run it from a directory I 
want to analyze, by just typing
    digest  .




From dudeja.rajat at gmail.com  Tue Jul  7 15:31:07 2009
From: dudeja.rajat at gmail.com (dudeja.rajat at gmail.com)
Date: Wed, 8 Jul 2009 01:01:07 +0530
Subject: Check file is locked?
Message-ID: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>

How to check if a particular file is locked by some application? (i.e. the
file is opened by some application)?

-- 
Regrads,
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/b78d6a0f/attachment.html>

From no.email at please.post  Tue Jul  7 15:37:20 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 19:37:20 +0000 (UTC)
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com> <h2vpko$jpk$1@panix3.panix.com>
Message-ID: <h3085g$c0m$1@reader1.panix.com>

In <h2vpko$jpk$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>In article <h2vcp9$66b$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>
>>Does anyone know where I can buy the Python library reference in
>>printed form?  (I'd rather not print the whole 1200+-page tome
>>myself.)  I'm interested in both/either 2.6 and 3.0.

>There used to be one for Python 2.1, but I can't tell whether it's ever
>been updated because the website isn't responding:

>http://wiki.python.org/moin/ReferenceBooks

Hmmm.  That's a shame.  How is one supposed to keep it under one's
pillow???

kj



From no.email at please.post  Tue Jul  7 15:38:32 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 19:38:32 +0000 (UTC)
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com>
	<YrCdnen05dNx_s7XnZ2dnUVZ_sudnZ2d@pdx.net>
Message-ID: <h3087o$c0m$2@reader1.panix.com>

In <YrCdnen05dNx_s7XnZ2dnUVZ_sudnZ2d at pdx.net> Scott David Daniels <Scott.Daniels at Acm.Org> writes:

>Also consider grabbing Gruet's "Python Quick Reference" page.

Not quite what I had in mind, but handy all the same.  Thanks.

kj


From pruebauno at latinmail.com  Tue Jul  7 15:51:26 2009
From: pruebauno at latinmail.com (nn)
Date: Tue, 7 Jul 2009 12:51:26 -0700 (PDT)
Subject: library search path when compiling python
Message-ID: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>

I am trying to compile python with ssl support but the libraries are
not in /usr/lib but in /opt/freeware/lib. How do I add that folder to
the default library search path?

It looks like configure --libdir=DIR might do the job but I don't want
to replace the default lib search path, just add an additional folder
to it.


From no.email at please.post  Tue Jul  7 16:04:46 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 20:04:46 +0000 (UTC)
Subject: tough-to-explain Python
Message-ID: <h309ot$bii$1@reader1.panix.com>



I'm having a hard time coming up with a reasonable way to explain
certain things to programming novices.

Consider the following interaction sequence:

>>> def eggs(some_int, some_list, some_tuple):
...     some_int += 2
...     some_list += [2]
...     some_tuple += (2,)
...
>>> x = 42
>>> y = (42,) 
>>> z = [42] 
>>> eggs(x, y, z)
>>> x
42
>>> y
(42,)
>>> z
[42, 2] 
>>> 

How do I explain to rank beginners (no programming experience at
all) why x and y remain unchanged above, but not z?

Or consider this one:

>>> ham = [1, 2, 3, 4]
>>> spam = (ham,)
>>> spam
([1, 2, 3, 4],)
>>> spam[0] is ham
True
>>> spam[0] += [5]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'tuple' object does not support item assignment
>>> ham += [5]
>>> spam
([1, 2, 3, 4, 5, 5],)
>>> 

What do you say to that?

I can come up with much mumbling about pointers and stacks and
heaps and much hand-waving about the underlying this-and-that, but
nothing that sounds even remotely illuminating.

Your suggestions would be much appreciated!

TIA!

kj


From lists at cheimes.de  Tue Jul  7 16:06:01 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 07 Jul 2009 22:06:01 +0200
Subject: library search path when compiling python
In-Reply-To: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>
References: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>
Message-ID: <4A53AAA9.9060307@cheimes.de>

nn wrote:
> I am trying to compile python with ssl support but the libraries are
> not in /usr/lib but in /opt/freeware/lib. How do I add that folder to
> the default library search path?
> 
> It looks like configure --libdir=DIR might do the job but I don't want
> to replace the default lib search path, just add an additional folder
> to it.

You didn't mention your OS. On Linux you can set the environment
variable LD_RUN_PATH prior to compiling Python. The env var sets the
rpath for the linker. See man ld(1) for details.

Christian


From lists at cheimes.de  Tue Jul  7 16:07:32 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 07 Jul 2009 22:07:32 +0200
Subject: Check file is locked?
In-Reply-To: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
Message-ID: <h309u4$901$1@ger.gmane.org>

dudeja.rajat at gmail.com wrote:
> How to check if a particular file is locked by some application? (i.e. the
> file is opened by some application)?

It depends on your operating system. By the way most operating systems
don't lock a file when it's opened for reading or writing or even executed.

Christian



From clp2 at rebertia.com  Tue Jul  7 16:08:50 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 7 Jul 2009 13:08:50 -0700
Subject: tough-to-explain Python
In-Reply-To: <h309ot$bii$1@reader1.panix.com>
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <50697b2c0907071308u375c81edt49fd2d1a2f6c7c34@mail.gmail.com>

On Tue, Jul 7, 2009 at 1:04 PM, kj<no.email at please.post> wrote:
>
>
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
> Consider the following interaction sequence:
>
>>>> def eggs(some_int, some_list, some_tuple):
> ... ? ? some_int += 2
> ... ? ? some_list += [2]
> ... ? ? some_tuple += (2,)
> ...
>>>> x = 42
>>>> y = (42,)
>>>> z = [42]
>>>> eggs(x, y, z)
>>>> x
> 42
>>>> y
> (42,)
>>>> z
> [42, 2]
>>>>
>
> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?
>
> Or consider this one:
>
>>>> ham = [1, 2, 3, 4]
>>>> spam = (ham,)
>>>> spam
> ([1, 2, 3, 4],)
>>>> spam[0] is ham
> True
>>>> spam[0] += [5]
> Traceback (most recent call last):
> ?File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
>>>> ham += [5]
>>>> spam
> ([1, 2, 3, 4, 5, 5],)
>>>>
>
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!

You might find the following helpful (partially):
http://effbot.org/zone/call-by-object.htm

Cheers,
Chris
-- 
http://blog.rebertia.com


From kevin.p.dwyer at gmail.com  Tue Jul  7 16:11:17 2009
From: kevin.p.dwyer at gmail.com (Kevin Dwyer)
Date: Tue, 7 Jul 2009 20:11:17 +0000 (UTC)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
Message-ID: <h30a55$88n$1@ger.gmane.org>

Hello,

I think this is discussed PEP 249 - see the "major changes" section.

http://www.python.org/dev/peps/pep-0249/

Kev

On Tue, 07 Jul 2009 10:05:07 -0700, dana wrote:

> I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
> modules together. Although I don't have Python 2.5, I've been informed
> the DBI module has been deprecated at 2.5. A few questions:
> 
> 1) Although deprecated, will it work at all in 2.5? Does the fact that
> it is deprecrated mean it has been removed entirely, or does Python 2.5
> simply issuing a warning?
> 
> 2) What do I use in place of DBI for my Python 2.4. scripts that import
> modules DBI and ODBC together. I don't use DBI directly. It was simply a
> dependency for the ODBC module as best I knew.
> 
> Thanks.
> 
> Dana




From deets at nospam.web.de  Tue Jul  7 16:15:40 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 07 Jul 2009 22:15:40 +0200
Subject: ISO library ref in printed form
In-Reply-To: <h3085g$c0m$1@reader1.panix.com>
References: <h2vcp9$66b$1@reader1.panix.com> <h2vpko$jpk$1@panix3.panix.com>
	<h3085g$c0m$1@reader1.panix.com>
Message-ID: <7bhoncF23eocqU1@mid.uni-berlin.de>

kj schrieb:
> In <h2vpko$jpk$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:
> 
>> In article <h2vcp9$66b$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>> Does anyone know where I can buy the Python library reference in
>>> printed form?  (I'd rather not print the whole 1200+-page tome
>>> myself.)  I'm interested in both/either 2.6 and 3.0.
> 
>> There used to be one for Python 2.1, but I can't tell whether it's ever
>> been updated because the website isn't responding:
> 
>> http://wiki.python.org/moin/ReferenceBooks
> 
> Hmmm.  That's a shame.  How is one supposed to keep it under one's
> pillow???


That's what netbooks were created for...

Diez


From piet at cs.uu.nl  Tue Jul  7 16:37:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 22:37:56 +0200
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <m2r5wsb55n.fsf@cs.uu.nl>

>>>>> kj <no.email at please.post> (kj) wrote:

>kj> Does anyone know where I can buy the Python library reference in
>kj> printed form?  (I'd rather not print the whole 1200+-page tome
>kj> myself.)  I'm interested in both/either 2.6 and 3.0.

Maybe you can have a copy printed at lulu.com. It would even be nicer if
the PSF would offer them at lulu. They could even make some money from
it if enough copies would be sold..
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at mrabarnett.plus.com  Tue Jul  7 16:40:20 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 21:40:20 +0100
Subject: Problem reading file with umlauts
In-Reply-To: <20090707190046.152740@gmx.net>
References: <20090707135949.100950@gmx.net> <4A53643C.4020905@xs4all.nl>
	<20090707190046.152740@gmx.net>
Message-ID: <4A53B2B4.9090409@mrabarnett.plus.com>

Claus Hausberger wrote:
> Thanks a lot. Now I am one step further but I get another strange error:
> 
> Traceback (most recent call last):
>   File "./read.py", line 12, in <module>
>     of.write(text)
> UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in position 0: ordinal not in range(128)
> 
> according to google ufeff has something to do with byte order.
> 
> I use an Linux system, maybe this helps to find the error.
> 
'text' contains Unicode, but you're writing it to a file that's not
opened for Unicode. Either open the output file for Unicode:

     of = codecs.open("umlaut-out.txt", "w", encoding="latin1")

or encode the text before writing:

     text = text.encode("latin1")

(I'm assuming you want the output file to be in Latin1.)

> 
>> Claus Hausberger wrote:
>>
>>> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
>>> change that as I do not create those files myself. I have to read
>>> those files and convert the umlauts like ? to stuff like &oumol; as
>>> the text files should become html files.
>> umlaut-in.txt:
>> ----
>> This file is contains data in the unicode
>> character set and is encoded with utf-8.
>> Viele R?hre. Macht spa?!  Ts?sch!
>>
>>
>> umlaut-in.txt hexdump:
>> ----
>> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
>> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
>> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e unicode..chara
>> 000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and is
>> 000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with utf
>> 000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele R..hr
>> 000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht spa..!
>> 000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00  Ts..sch!.......
>>
>>
>> umlaut.py:
>> ----
>> # -*- coding: utf-8 -*-
>> import codecs
>> text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
>> text=text.replace(u"?",u"oe")
>> text=text.replace(u"?",u"ss")
>> text=text.replace(u"?",u"ue")
>> of=open("umlaut-out.txt","w")
>> of.write(text)
>> of.close()
>>
>>
>> umlaut-out.txt:
>> ----
>> This file is contains data in the unicode
>> character set and is encoded with utf-8.
>> Viele Roehre. Macht spass!  Tsuesch!
>>
>>
>> umlaut-out.txt hexdump:
>> ----
>> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
>> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
>> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e unicode...char
>> 000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and is
>> 000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with ut
>> 000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele Roe
>> 000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht spass
>> 000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 !  Tsuesch!.....
>>
>>
>>
>>
>>
>> -- 
>> "The ability of the OSS process to collect and harness
>> the collective IQ of thousands of individuals across
>> the Internet is simply amazing." - Vinod Valloppillil
>> http://www.catb.org/~esr/halloween/halloween4.html
> 



From piet at cs.uu.nl  Tue Jul  7 16:53:13 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 22:53:13 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <m2my7gb4g6.fsf@cs.uu.nl>

>>>>> kj <no.email at please.post> (k) wrote:

>k> I'm having a hard time coming up with a reasonable way to explain
>k> certain things to programming novices.

>k> Consider the following interaction sequence:

>>>>> def eggs(some_int, some_list, some_tuple):
>k> ...     some_int += 2
>k> ...     some_list += [2]
>k> ...     some_tuple += (2,)
>k> ...
>>>>> x = 42
>>>>> y = (42,) 
>>>>> z = [42] 
>>>>> eggs(x, y, z)
>>>>> x
>k> 42
>>>>> y
>k> (42,)
>>>>> z
>k> [42, 2] 
>>>>> 

>k> How do I explain to rank beginners (no programming experience at
>k> all) why x and y remain unchanged above, but not z?

You shouldn't. That's not for beginners. Leave it waiing until you get
to the advanced level.

>k> Or consider this one:

>>>>> ham = [1, 2, 3, 4]
>>>>> spam = (ham,)
>>>>> spam
>k> ([1, 2, 3, 4],)
>>>>> spam[0] is ham
>k> True
>>>>> spam[0] += [5]
>k> Traceback (most recent call last):
>k>   File "<stdin>", line 1, in <module>
>k> TypeError: 'tuple' object does not support item assignment
>>>>> ham += [5]
>>>>> spam
>k> ([1, 2, 3, 4, 5, 5],)
>>>>> 

>k> What do you say to that?

Mutable and immutable. But use different examples. Like

ham = [1, 2, 3, 4]
spam = (1, 2, 3, 4)

spam[0] += 1 will give the same error message. You can't change the
components of a tuple.

Your example above is similar. The spam[0] += [5] appends the 5 to the
list in spam[0] (so it appends to ham), and then tries to assign the
result of it to spam[0], which is not allowed. That the item it tries to
assign is the same as the item that was already there doesn't matter.

So dont't forget += is a real assignment, even when it is an in-place
modification.  Your example just proves that. The language ref manual
says:

    With the exception of assigning to tuples and multiple targets in a
    single statement, the assignment done by augmented assignment
    statements is handled the same way as normal assignments.

But I think that your example isn't for beginners either.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From joshua at joshuakugler.com  Tue Jul  7 17:07:55 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Tue, 07 Jul 2009 13:07:55 -0800
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org> <h2up7a$epu$1@ger.gmane.org>
Message-ID: <h30dfc$ke2$1@ger.gmane.org>

Roger Binns wrote:
> Joshua Kugler wrote:
>> BTW, APSW is written by the same author as pysqlite.
> Not even remotely true :-)

Sorry about that...since pysqlite and APSW are both discusses on the
pysqlite list, I had made an incorrect assumption. Oops.

j



From no.email at please.post  Tue Jul  7 17:11:29 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 21:11:29 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com> <m2my7gb4g6.fsf@cs.uu.nl>
Message-ID: <h30dm1$g56$1@reader1.panix.com>

In <m2my7gb4g6.fsf at cs.uu.nl> Piet van Oostrum <piet at cs.uu.nl> writes:

>>>>>> kj <no.email at please.post> (k) wrote:

>>k> I'm having a hard time coming up with a reasonable way to explain
>>k> certain things to programming novices.

>>k> Consider the following interaction sequence:

>>>>>> def eggs(some_int, some_list, some_tuple):
>>k> ...     some_int += 2
>>k> ...     some_list += [2]
>>k> ...     some_tuple += (2,)
>>k> ...
>>>>>> x = 42
>>>>>> y = (42,) 
>>>>>> z = [42] 
>>>>>> eggs(x, y, z)
>>>>>> x
>>k> 42
>>>>>> y
>>k> (42,)
>>>>>> z
>>k> [42, 2] 
>>>>>> 

>>k> How do I explain to rank beginners (no programming experience at
>>k> all) why x and y remain unchanged above, but not z?

>You shouldn't. That's not for beginners.

No, of course not.  And I don't plan to present these examples to
them.  But beginners have a way of bumping into such conundrums
all on their own, and, as a former beginner myself, I can tell you
that they find them, at best, extremely frustrating, and at worst,
extremely discouraging.  I doubt that an answer of the form "don't
worry your pretty little head over this now; wait until your second
course" will do the trick.

Thanks for your comments!

kj


From no.email at please.post  Tue Jul  7 17:18:53 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 21:18:53 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
Message-ID: <h30e3t$g56$2@reader1.panix.com>

In <mailman.2796.1246997332.8015.python-list at python.org> Chris Rebert <clp2 at rebertia.com> writes:

>You might find the following helpful (partially):
>http://effbot.org/zone/call-by-object.htm


Extremely helpful.  Thanks!  (I learned more from it than someone
who will teach the stuff would care to admit...)

I had not realized how *profoundly* different the meaning of the
"=" in Python's

  spam = ham

is from the "=" in its

  spam[3] = ham[3]

So much for "explicit is better than implicit"...


And it confirmed Paul Graham's often-made assertion that all of
programming language design is still catching up to Lisp...

kj


From james at agentultra.com  Tue Jul  7 17:21:26 2009
From: james at agentultra.com (J Kenneth King)
Date: Tue, 07 Jul 2009 17:21:26 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
	<fc6b4e6a-5e89-4fed-914b-232fc6b1cf0e@h18g2000yqj.googlegroups.com>
Message-ID: <85hbxodwa1.fsf@agentultra.com>

Dr Mephesto <dnhkng at googlemail.com> writes:

> Sure, I am learning Objective C already, but the syntax is really
> unfriendly after python.
>
> I think it really depends on the type of app you want to write.
> Anything held back by network delays or that sits around waiting for
> user input are perfectly acceptable target apps. If you need speed for
> something really intensive, falling back to C is still much nicer than
> coding in Objective C. I agree that having a certain basic
> understanding of objective C is a must, but having the option to use a
> coder-friendly language like Ruby or Python can cut development time
> dramatically.
>
> If Ruby can do it (and it generally slower than python), why can
> Python also get a legal iPhone interpreter?

It can if you want to write the interpreter.

I just don't see the point.

I can understand wanting a higher level language than assembler or maybe
even C, but that's precisely what Objective-C is.

Unfortunately, while the hardware for these mobile platforms is getting
better these days, it's still not where it needs to be to run programs
written in interpreted languages, IMO.  Users typically only interact
with an app for around two minutes at a time.  Your app needs to be as
fast as it can be.  It's one of the few areas of software development
today where optimizations can be justified (the other are games and
scientific computing).

Trust me, if there were an SMS app for the iPhone that loaded faster
than the one that ships with it, guaranteed it would sell like hot-cakes
(if Apple would let it in the store of course).

If you do write the interpreter, let me know.  I would certainly
experiment with it.


From bearophileHUGS at lycos.com  Tue Jul  7 17:46:01 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 7 Jul 2009 14:46:01 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>

kj, as Piet van Oostrum as said, that's the difference between mutable
an immutable. It comes from the procedural nature of Python, and
probably an explanation of such topic can't be avoided if you want to
learn/teach Python.

Lot of people think that a language where everything is immutable is
simpler for newbies to understand (even if they have to learn what
higher-order functions are). That's why some people think Scheme or
other languages (even Clojure, I guess) are better for novices (Scheme
has mutability, but you can avoid showing it to newbies).

Some people say that languages that mostly encourage the use of
immutable data structures (like F#, Clojure, Scala and many other less
modern ones) help avoid bugs, maybe for novices too.

On the other hand, it's hard or impossible to actually remove
complexity from a system, and you usually just move it elsewhere. So
other things will become harder to do for those novices. I have no
idea if for the average novice it's simpler to learn to use a
immutables-based language instead of a mutables-based one (it can also
be possible that some novices prefer the first group, and other
novices prefer the second group).

>From what I have seen lot of students seem able to learn Python, so
it's not a bad choice.

Python isn't perfect, and in *many* situations it is pragmatic, for
example to increase its performance. Generally for a novice programmer
running speed is not important, but it's important to have a really
coherent and clean language. I've personally seen that for such people
even Python looks very "dirty" (even if it's one of the less dirty
ones).

For example a novice wants to see 124 / 38 to return the 62/19
fraction and not 3 or 3.263157894736842 :-)

People may be able to invent a clean and orthogonal language that's
easy to use and has very few compromises, fit for newbies. But this
language may be very slow, not much useful in practice (who knows?
Maybe there's a practical niche even for such very high level
language), and it doesn't teach how to use lower level languages like
C :-)

Today I think there are no languages really fit for teaching. Python
is one of the few fit ones, but it's getting more and more complex as
time passes because it's getting used in more and more complex real
world situations (a language fit for newbies must not have abstract
base classes, decorators, etc). D language is too much complex for a
newbie. Java is not too much bad, but it's requires to write too much
code, it's too much fussy (semicolons at the end of lines? Newbies say
that the computer is an idiot when it refuses code just because
there's a missing useless semicolon!), and it misses some necessary
things (first class functions! Damn). A nice language like Boo running
on the Mono VM seems another option :-)

In the past Pascal was good enough, but I think it's not good enough
anymore. The problem is that teaching is a niche activity (even if a
very important one). PLT Scheme is one of the few environments (beside
Squeak, Python itself, and little more) that look refined and
implemented well enough for such purpose.

See you later,
bearophile


From andrew.henshaw at gtri.gatech.edu  Tue Jul  7 17:48:37 2009
From: andrew.henshaw at gtri.gatech.edu (Andrew Henshaw)
Date: Tue, 7 Jul 2009 17:48:37 -0400
Subject: finding most common elements between thousands of multiple arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <h30ft1$f0f$1@news-int.gatech.edu>


"mclovin" <hanooter at gmail.com> wrote in message 
news:c5332c9b-2348-4194-bfa0-d70c7710765d at x3g2000yqa.googlegroups.com...
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
>
> so I set up a dictionary to handle the counting so when I am
> iterating  I up the count on the corrosponding dictionary element. I
> then iterate through the dictionary and find the 25 most common
> elements.
>
> the elements are initially held in a array within an array. so I am am
> just trying to find the most common elements between all the arrays
> contained in one large array.
> my current code looks something like this:
> d = {}
> for arr in my_array:
> -----for i in arr:
> #elements are numpy integers and thus are not accepted as dictionary
> keys
> -----------d[int(i)]=d.get(int(i),0)+1
>
> then I filter things down. but with my algorithm that only takes about
> 1 sec so I dont need to show it here since that isnt the problem.
>
>
> But there has to be something better. I have to do this many many
> times and it seems silly to iterate through 2 million things just to
> get 25. The element IDs are integers and are currently being held in
> numpy arrays in a larger array. this ID is what makes up the key to
> the dictionary.
>
> It currently takes about 5 seconds to accomplish this with my current
> algorithm.
>
> So does anyone know the best solution or algorithm? I think the trick
> lies in matrix intersections but I do not know.

Would the following work for you, or am I missing something?  For a 5Kx5K 
array, this takes about a tenth of a second on my machine.  This code 
doesn't deal with the sub-array issue.

#####################
import numpy
import time

LOWER = 0
UPPER = 1024
SIZE = 5000
NUM_BEST = 4

# sample data
data = numpy.random.randint(LOWER, UPPER, (SIZE,SIZE)).astype(int)

time.clock()
count = numpy.bincount(data.flat)
best = sorted(zip(count, range(len(count))))[-NUM_BEST:]
print 'time=', time.clock()
print best





From python at bdurham.com  Tue Jul  7 17:54:14 2009
From: python at bdurham.com (python at bdurham.com)
Date: Tue, 07 Jul 2009 17:54:14 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
In-Reply-To: <85hbxodwa1.fsf@agentultra.com>
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
	<fc6b4e6a-5e89-4fed-914b-232fc6b1cf0e@h18g2000yqj.googlegroups.com>
	<85hbxodwa1.fsf@agentultra.com>
Message-ID: <1247003654.9346.1323970563@webmail.messagingengine.com>

> If you do write the interpreter, let me know. I would certainly experiment with it.

+2 over here!

Malcolm


From nobody at nowhere.com  Tue Jul  7 18:37:43 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 07 Jul 2009 23:37:43 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
	<6xB4m.21104$vi5.8567@uutiset.elisa.fi>
Message-ID: <pan.2009.07.07.22.37.43.422000@nowhere.com>

On Tue, 07 Jul 2009 09:01:39 +0300, jack catcher (nick) wrote:

> Thanks for the comments. Unfortunately, such specifications aren't easy 
> to find, even in reviews. Fortunately several newer webcams seem at 
> least to use usb2.

Supporting USB-2 doesn't mean that the camera necessarily uses high-speed
(480Mbit/sec).

AFAIK, the only real difference between "USB-1 conformant" and "USB-2
conformant" is that the latter actually passed a test of its ability to
say "no, I can't do high-speed", while the former didn't. The check for
high-speed capability was designed such that it shouldn't cause problems
for USB-1 devices, but individual USB-1 devices weren't actually tested
for this.



From gagsl-py2 at yahoo.com.ar  Tue Jul  7 18:50:57 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 19:50:57 -0300
Subject: Python Error from Apress book
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
	<4A5345B1.8050306@ieee.org>
Message-ID: <op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
> Gabriel Genellina wrote:
>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com>  
>> escribi?:

>>> When I try to run the command as outlined in
>>> the book "simple_markup2.py < test_input.txt > test_output.html i get  
>>> the
>>> following error every time.
>>>
>>> IOError: [Errno 9] Bad file descriptor
>>
>> That's a Windows problem. When you execute the script as itself (either  
>> as you do in the command line, or by double-clicking on it), it doesn't  
>> have valid standard handles.
>> You have to invoke Python explicitely:
>>
>> python simple_markup2.py < test_input.txt > test_output.html
>>
>> (you may need to specify the full path to python.exe, or add the  
>> directory where Python is installed to your system PATH).
>>
> I use stdout this way all the time, with no problem (python 2.6, Windows  
> XP).  But as you point out, stdin redirection doesn't seem to work using  
> the file associations.  I do get a different error though. When I look  
> at sys.stdin, it shows an open file, with handle of zero, as expected.   
> But when I do a raw_input(), it gets:
>      EOFError: EOF when reading a line

I think the error depends on the specific OS version/service pack. But at  
least on XP this appears to fix it:

http://support.microsoft.com/kb/321788/en-us

-- 
Gabriel Genellina



From philr at aspexconsulting.co.nz  Tue Jul  7 19:04:25 2009
From: philr at aspexconsulting.co.nz (Phil Runciman)
Date: Wed, 8 Jul 2009 11:04:25 +1200
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2ujrs$4c0$1@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
Message-ID: <F232DBBD675E6E43A3BAC15A4F6767E6338256C967@FP-SBS2K8.aspex.co.nz.local>


-----Original Message-----
From: Dennis Lee Bieber [mailto:wlfraed at ix.netcom.com] 
Sent: Tuesday, 7 July 2009 4:45 p.m.
To: python-list at python.org
Subject: Re: A Bug By Any Other Name ...

On Mon, 6 Jul 2009 19:48:39 -0700, Daniel Fetchinson
<fetchinson at googlemail.com> declaimed the following in
gmane.comp.python.general:

> Yes, there are plenty of languages other than Java and C, but the
> influence of C is admittedly huge in Python. Why do you think loops
> are called "for", conditionals "if" or "while", functions return via
> "return", loops terminate via "break" and keep going via "continue"
> and why is comparison written as "==", etc, etc? All of these are
> coming from C (or an even earlier language) and my point is that users

	for, if, and return were common keywords in FORTRAN.

	Not to mention BASIC

	Both of which predate C

-- 
__________________________________________________________________________

Guido was probably influenced by the ALGOL language stream, which used "for" and "if". ALGOL 60 was a joint American and European effort and was significant in the late 50s and 60's.

Guido's fellow countryman, Edsgar Dijkstra, took this publication language (the ALGOL60 version) and produced a compiler for it. (It was not the first, but was very early on). Then B. Randell and L.J. Russell visited him, learnt from his experiences and returned to the UK to produce the KDF9 Whetstone ALGOL60 Compiler. Their book "ALGOL 60 Implementation" was a very early and influential book in the field and occupies a significant place in the history of computing. Computer language designers, including Nicholas Wirth (Pascal, Modula, Oberon), have been influenced by ALGOL.

Sadly, "C" and its ilk, come from a totally different stream of language development beginning with the likes of "CPL", "BCPL", "B" and developing into "C" and "C++". This stream was originally focussed on language portability and performance. This stream was much closer to the assembler language end of the language spectrum, whereas the other stream was heavily biased towards publication and later teaching. 

I could say more but will restrain myself.

My 2c 

Phil

FWIW "++" reeks of assembler language notation.

The KDF9 Whetstone ALGOL60 Compiler was the one I used at Whetstone for 1-Dimensional Transient Heat-Flow calculations and Steam-Table generation. Our course on it was 2.5 days long. We had wonderful training by English Electric, Kidsgrove staff. I hate to think how long the same course would be now, a month? 



From norseman at hughes.net  Tue Jul  7 19:07:04 2009
From: norseman at hughes.net (norseman)
Date: Tue, 07 Jul 2009 16:07:04 -0700
Subject: tough-to-explain Python
In-Reply-To: <a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
Message-ID: <4A53D518.6080306@hughes.net>

Bearophile wrote:
> kj, as Piet van Oostrum as said, that's the difference between mutable
> an immutable. It comes from the procedural nature of Python, and
> probably an explanation of such topic can't be avoided if you want to
> learn/teach Python.
...(snip)
> 
> See you later,
> bearophile

==========================Perhaps because it is the way I learned or the 
way I "naturally" approach programming, or maybe the way one influences 
the other, but at any rate I think "newbies" to programming should first 
learn a few basic concepts (if/then, for, while, do and other loops and 
other control constructs) and then be forced to deal with the computer 
on it's own terms. Assembly. Once the student learns what the computer 
already knows, that the whole thing is just bits and the combination of 
them determines it's responses, it then becomes easier to present 
'idealistic' concepts and their implementations.  With the knowledge and 
'mental picture' of the computer's nature the rest of the ideas for 
programming have a tendency to drift in the direction of reality and the 
underlying needs to fulfill the 'better' and/or 'easier' languages. 
Having both the knowledge of the 'full capabilities' of a computer and 
the experience of a formalized language the student can, or should, 
learn/compare the trade offs of each.  By understanding the computer (I 
at least) grasp the basics of a new language quite quickly. No, I don't 
become a guru overnight, if at all, but I do have the advantage in 
deciding if a given language is appropriate for a given job with very 
little research.

The more I delve into OOP the more I liken an 'object' to a box. A box 
with a shipping manifest.

There are big boxes,
little boxes,
squat boxes and so on.

A box can contain corn flakes,
bullets, raisins, rice, burlap, silk, motorcycle(s), soap and more.

The manifest describes contents.
The manifest is there but the description(s) change with content (type).
The descriptions always use one or more of the basics like: color, 
count, dimension and so forth.

Just like an OOP object.

A box can contain things of all sorts, including references to the 
contents of other box(es). A box can even be a virtual of another (the 
global concept).  The return statement, in this context, means hauling 
the contents of the box (and/or its manifest) back to (wherever) and 
disposing of the current box (a local).

Just like an OOP object.


It is easier to visualize a box and it's use than a non described blob.
Abstracts are never precise -  hence the evolution of the word.


The one thing a teacher will always fail is the same as anyone else who 
tries to adequately describe a pretty sunset to a person born totally 
blind. No point(s) of reference.



Time for me to sign off.  To all those that helped me when I needed it -

I thank you very much.

Food for thought: your watch (clock) does not tell time.
The watch (clock) only mimics one movement of the earth.
ie... 3 dimensions are still static, the 4th is movement.


Steve


From stef.mientki at gmail.com  Tue Jul  7 19:12:08 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Wed, 08 Jul 2009 01:12:08 +0200
Subject: Python/pyobjC Apps on iPhone now a possibility?
In-Reply-To: <85ljn0ej4h.fsf@agentultra.com>
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
Message-ID: <4A53D648.60005@gmail.com>


>> So, the question is, can the same thing be done for Python apps?
>>     
>
> I love Python and all, but it'd be apt to ask, what's the point?
>
> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
> device are already limited; running your program on top of an embedded
> Python interpreter would only be adding pressure to the constraints;
> even if it was an optimized interpreter.
>   
I don't know iPhone,
but I've done some experiments with 400 MHz arm, running Windows Mobile,
and found PocketPyGUI running very very well on these devices.

cheers,
Stef Mientki


From james at agentultra.com  Tue Jul  7 19:29:25 2009
From: james at agentultra.com (J Kenneth King)
Date: Tue, 07 Jul 2009 19:29:25 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
	<mailman.2804.1247008319.8015.python-list@python.org>
Message-ID: <85d48cdqcq.fsf@agentultra.com>

Stef Mientki <stef.mientki at gmail.com> writes:

>>> So, the question is, can the same thing be done for Python apps?
>>>     
>>
>> I love Python and all, but it'd be apt to ask, what's the point?
>>
>> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>> device are already limited; running your program on top of an embedded
>> Python interpreter would only be adding pressure to the constraints;
>> even if it was an optimized interpreter.
>>   
> I don't know iPhone,
> but I've done some experiments with 400 MHz arm, running Windows Mobile,
> and found PocketPyGUI running very very well on these devices.
>
> cheers,
> Stef Mientki

Sure, but it's pretty relative in the sense that it might be fast enough
if I'm sitting around but too slow if I want to enter some information
in the app before the next train comes.

As a programmer, I don't really see the benefit of using an embedded
interpreter on the iPhone.  Objective-C isn't the greatest language, but
it's easy to learn and well supported.  It also compiles into some
pretty speedy executables.

If you can sacrifice a little run-time speed for your users in exchange
for ease of development on your part, all the more to you.

My original point was that I don't see the benefit in that decision.




From gagsl-py2 at yahoo.com.ar  Tue Jul  7 19:44:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 20:44:45 -0300
Subject: Embedded Python : Why does thread lock here?
References: <00e8b4e8-5386-4f3d-b900-ab1ba41294f2@q40g2000prh.googlegroups.com>
Message-ID: <op.uwp1kvndx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 15:01:17 -0300, roschler <robert.oschler at gmail.com>  
escribi?:

> I have the Python Intepreter embedded in a Delphi (Object Pascal)
> program.  In the Python script shown below, I have a module that
> creates a thread object and starts it.

Do you *execute* the module or do you *import* it?
Isn't a good idea to spawn a thread by side effect of importing a module.

> The thread's run() call calls
> a function called deleteOutputVariables() declared at the module
> level.  In my code's first incarnation the thread's run() call would
> deadlock when trying to call the deleteOutputVariables() function
> declared at Module level.  I would never see the statement
> "(deleteOutputVariables) Top of Call" printed to the screen.  I now
> know that I must periodically call join() with a very fast time-out to
> keep Python threads happy, and that solved the problem.

What does the Delphi code? Isn't a join with a long timeout enough?

> However I am
> curious as to why it deadlocked at the deleteOutputVariables() call?
> Is it because deleteOutputVariables() is declared at the module level
> or because that function deletes module level variables?  If so why?

I don't know, but you can make some experiments - move te  
deleteOutputVariables as a method, or don't delete module level variables  
at all, and see what happens. I'd say both factors are irrelevant.

> # FUNCTION: Delete the variables given in the list.
> def deleteOutputVariables(theModule, theOutputVariablesListOfNames):
>     try:
>         print "(deleteOutputVariables) Top of call."
>         for theOutputVariableName in theOutputVariablesListOfNames:
>             if theModule.__dict__.has_key(theOutputVariableName):
>                 print "(Python::deleteOutputVariables) Deleting the
> Output Variable named " + theOutputVariableName
>                 del theModule.__dict__[theOutputVariableName]
>     except:
>         print "(deleteOutputVariables) Exception occurred."

As a rule, avoid using __special__ names. There is almost never need of  
using them (__init__ is a notable exception) unless you want to change  
Python behaviour.
In this case:

for theOutputVariableName in theOutputVariablesListOfNames:
   if hasattr(theModule, theOutputVariableName):
     delattr(theModule, theOutputVariableName)

(a name like theOutputVariablesListOfNames is too long for my taste, but  
that's a matter of style...)

> theNewThread = None
> theNewThread = threadRun("TestThread")

That first line is useless...

-- 
Gabriel Genellina



From stef.mientki at gmail.com  Tue Jul  7 19:46:51 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Wed, 08 Jul 2009 01:46:51 +0200
Subject: Python/pyobjC Apps on iPhone now a possibility?
In-Reply-To: <85d48cdqcq.fsf@agentultra.com>
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>	<85ljn0ej4h.fsf@agentultra.com>	<mailman.2804.1247008319.8015.python-list@python.org>
	<85d48cdqcq.fsf@agentultra.com>
Message-ID: <4A53DE6B.8040706@gmail.com>

J Kenneth King wrote:
> Stef Mientki <stef.mientki at gmail.com> writes:
>
>   
>>>> So, the question is, can the same thing be done for Python apps?
>>>>     
>>>>         
>>> I love Python and all, but it'd be apt to ask, what's the point?
>>>
>>> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>>> device are already limited; running your program on top of an embedded
>>> Python interpreter would only be adding pressure to the constraints;
>>> even if it was an optimized interpreter.
>>>   
>>>       
>> I don't know iPhone,
>> but I've done some experiments with 400 MHz arm, running Windows Mobile,
>> and found PocketPyGUI running very very well on these devices.
>>
>> cheers,
>> Stef Mientki
>>     
>
> Sure, but it's pretty relative in the sense that it might be fast enough
> if I'm sitting around but too slow if I want to enter some information
> in the app before the next train comes.
>
> As a programmer, I don't really see the benefit of using an embedded
> interpreter on the iPhone.  Objective-C isn't the greatest language, but
> it's easy to learn and well supported.  It also compiles into some
> pretty speedy executables.
>
> If you can sacrifice a little run-time speed for your users in exchange
> for ease of development on your part, all the more to you.
>
> My original point was that I don't see the benefit in that decision.
>
>
>   
ok 20 years ago I might have agreed with you,
but now a days,
speed of development is a much more important decision maker than speed 
of execution ;-)

cheers,
Stef


From freelancer317 at gmail.com  Tue Jul  7 19:49:54 2009
From: freelancer317 at gmail.com (Bret Fledderjohn)
Date: Tue, 7 Jul 2009 19:49:54 -0400
Subject: tough-to-explain Python
In-Reply-To: <4A53D518.6080306@hughes.net>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<4A53D518.6080306@hughes.net>
Message-ID: <b1d973a70907071649x126ee890wc7722f8d44449c24@mail.gmail.com>

I really enjoyed your boxes analogy, from a guy with a trucking background,
it makes a lot of sense!
-Bret


> ... The more I delve into OOP the more I liken an 'object' to a box. A box
> with a shipping manifest.
>
> There are big boxes,
> little boxes,
> squat boxes and so on.
>
> A box can contain corn flakes,
> bullets, raisins, rice, burlap, silk, motorcycle(s), soap and more.
>
> The manifest describes contents.
> The manifest is there but the description(s) change with content (type).
> The descriptions always use one or more of the basics like: color, count,
> dimension and so forth.
>
> Just like an OOP object.
>
> A box can contain things of all sorts, including references to the contents
> of other box(es). A box can even be a virtual of another (the global
> concept).  The return statement, in this context, means hauling the contents
> of the box (and/or its manifest) back to (wherever) and disposing of the
> current box (a local).
>
> Just like an OOP object.
>
>
> It is easier to visualize a box and it's use than a non described blob.
> Abstracts are never precise -  hence the evolution of the word.
>
>
> The one thing a teacher will always fail is the same as anyone else who
> tries to adequately describe a pretty sunset to a person born totally blind.
> No point(s) of reference.
>
>
>
> Time for me to sign off.  To all those that helped me when I needed it -
>
> I thank you very much.
>
> Food for thought: your watch (clock) does not tell time.
> The watch (clock) only mimics one movement of the earth.
> ie... 3 dimensions are still static, the 4th is movement.
>
>
> Steve


-- 
- Bret
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/83155beb/attachment.html>

From ldo at geek-central.gen.new_zealand  Tue Jul  7 19:57:35 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 08 Jul 2009 11:57:35 +1200
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
Message-ID: <h30ndf$vho$1@lust.ihug.co.nz>

In message <mailman.2795.1246997268.8015.python-list at python.org>, Christian 
Heimes wrote:

> By the way most operating systems don't lock a file when it's opened for
> reading or writing or even executed.

The general conclusion seems to be that mandatory locking is more trouble 
than it's worth.



From ben+python at benfinney.id.au  Tue Jul  7 20:06:07 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Wed, 08 Jul 2009 10:06:07 +1000
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
	<h30e3t$g56$2@reader1.panix.com>
Message-ID: <8763e4ox74.fsf@benfinney.id.au>

kj <no.email at please.post> writes:

> In <mailman.2796.1246997332.8015.python-list at python.org> Chris Rebert <clp2 at rebertia.com> writes:
> 
> >You might find the following helpful (partially):
> >http://effbot.org/zone/call-by-object.htm
> 
> Extremely helpful.  Thanks!  (I learned more from it than someone
> who will teach the stuff would care to admit...)

I have got very good results from teaching using the analogy of ?paper
tags tied to physical objects? to describe Python's references to
values.

The analogy allows illustration of many otherwise confusing facts:

  * an assignment is the act of putting a tag onto an object

  * a tag leads to exactly one object, and it can be re-tied to a
    different object

  * an object can have arbitrarily many tags on it

  * containers (e.g. lists, dicts, sets, etc.) don't contain objects,
    they contain tags leading to objects

  * passing arguments to a function always makes new tags leading to the
    objects passed in, and throws those new tags away once the function
    returns

  * etc.

The analogy can then be contrasted to how Python *doesn't* do it: named
boxes with one value per box. You can point out that many other
languages do use this model, so they should be aware of it, but Python
doesn't use it.

> I had not realized how *profoundly* different the meaning of the
> "=" in Python's
> 
>   spam = ham

Access the object referenced by ?ham?, and assigns the reference ?spam?
to that object.

> is from the "=" in its
> 
>   spam[3] = ham[3]

Access the object referenced by ?ham[3]?, and assigns the reference
?spam[3]? to that object.

No, they're exactly the same. The only thing that's different is the
references you use; the assignment operates *exactly* the same in both
cases.

-- 
 \     ?We are no more free to believe whatever we want about God than |
  `\         we are free to adopt unjustified beliefs about science or |
_o__)              history [?].? ?Sam Harris, _The End of Faith_, 2004 |
Ben Finney


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 20:45:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 21:45:15 -0300
Subject: Write matrix to text file
References: <564970db0907071046o60e927dao21cc0557f1fa2903@mail.gmail.com>
Message-ID: <op.uwp4dpwvx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 14:46:47 -0300, Hanna Michelsen <hannarosie at gmail.com>  
escribi?:

> I'm working with both python and matlab at the moment and I was  
> wondering if
> there is an efficient way to take a 2-D array (of 1s and 0s) in python  
> and
> write it to a text file such that matlab will be able to create a sparse
> matrix from it later.

Your yesterday post appeared on this list successfully.
Posting the very same text again isn't going to help - those that are  
reading it now are likely the same that read it before.
If nobody replied, assume that something is wrong with the question  
itself. Not the grammar, looks clear to me. Maybe the meaning: you say "a  
2-D array" but you don't say what that means (a list? an array.array  
object? a Numpy array?).

Consider *who* might be able to answer: someone that knows both Python and  
matlab, and knows how to use a sparse matrix, and knows how to read data  
 from files, and knows how to generate such files from Python. The last  
part is the easy part, because people here is supposed to know how to do  
things in Python; but not how matlab works. So, please help people help  
you: tell us what file format would be fine for matlab to read, and people  
here surely will suggest the best way to write that in Python.

Reading http://www.mikeash.com/getting_answers.html may help too.

-- 
Gabriel Genellina



From gallium.arsenide at gmail.com  Tue Jul  7 20:55:13 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Tue, 7 Jul 2009 17:55:13 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com> <m2my7gb4g6.fsf@cs.uu.nl> 
	<h30dm1$g56$1@reader1.panix.com>
Message-ID: <8fa4563b-9de7-44cb-a8a2-a6d7c87a0ce4@q11g2000yqi.googlegroups.com>

On Jul 7, 5:11?pm, kj <no.em... at please.post> wrote:
> I don't plan to present these examples to them.
> But beginners have a way of bumping into such
> conundrums all on their own [...]. ?I doubt that
> an answer of the form "don't worry your pretty
> little head over this now; wait until your second
> course" will do the trick.

I agree that beginners are bound to come across difficult issues on
their own, and when they do, you have to at least try to explain,
rather than dismiss them.  I believe that the beginners which are most
curious, and thus most likely to run into things you didn't plan for
them, are also most likely to be ready and able to receive your
explanation.

That said, I think it's worth planning a fairly controlled flow of
information.  For example, you can go a LONG way without touching
tuples or the augmented assignment operators.

For your function example, I suppose the key ideas to understand are
binding and containers (which may or may not be mutable).  The
oversimplified version I think I would attempt to explain is that, as
far as the "outside world" is concerned, a function cannot rebind the
arguments passed to it.  However, the contents of a mutable container
may be altered without rebinding.  That is, you can hold a bucket,
pass that bucket to a function, and the function can put stuff in the
bucket or take stuff out without you ever letting go of the bucket.
When the function returns, you are still holding the bucket.

Nested containers, especially with "outside" bindings to inner
containers, may be tougher to visualize with real-world objects.
Hopefully by then the students can grasp a more abstract (pointerlike)
notion of binding!  Good luck!

John


From usernet at ilthio.net  Tue Jul  7 20:59:05 2009
From: usernet at ilthio.net (Tim Harig)
Date: Wed, 08 Jul 2009 00:59:05 GMT
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
Message-ID: <tbS4m.2451$Wj7.1467@nlpi065.nbdc.sbc.com>

On 2009-07-08, Fred Atkinson <fatkinson at mishmash.com> wrote:
> 	Is there a Python function I can use to get the user's IP
> address so I can display it on his browser?  

If you are using CGI you can get it from the REMOTE_ADDR environmental
variable.


From clp2 at rebertia.com  Tue Jul  7 21:09:09 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 7 Jul 2009 18:09:09 -0700
Subject: IP Address Function
In-Reply-To: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
Message-ID: <50697b2c0907071809y57b78162odd06b94cfff54d01@mail.gmail.com>

On Tue, Jul 7, 2009 at 6:45 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
> ? ? ? ?Is there a Python function I can use to get the user's IP
> address so I can display it on his browser?

from socket import gethostname, gethostbyname
ip = gethostbyname(gethostname())

Cheers,
Chris
-- 
http://blog.rebertia.com


From http  Tue Jul  7 21:24:28 2009
From: http (Paul Rubin)
Date: 07 Jul 2009 18:24:28 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
	<1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>
	<1f09e856-bd04-4d27-bf51-5d67953a7e13@y7g2000yqa.googlegroups.com>
Message-ID: <7xskh83r1v.fsf@ruckus.brouhaha.com>

pdpi <pdpinheiro at gmail.com> writes:
>     while abs(func(guess) - target) > epsilon:
>         guess = (lo + hi) / 2.
>         if sense * func(guess) > sense * target:
>             hi = guess
>         elif sense * func(guess) < sense * target:
>             lo = guess
>         elif lo == hi:
>             return None
>     return guess

That is completely confusing.  I get the, er, impression that "sense"
is supposed to change during the loop, and it takes much head
scratching to tell whether what you have there is right or not.  Also,
it calls func 3 times on each loop, which could be extremely slow.
You don't know what func does, so eliminating 2/3 of the calls to it
is not a micro-optimization--it could be a major time saving.

Yet another version:

    def _binary_search(x0, x1, func, target, epsilon):
        y0,y1 = func(x0), func(x1)
        while abs(y1 - target) > epsilon:
            if x0 == x1 or cmp(y0,target) == cmp(y1,target):
                return None
            xn = (x0 + x1) / 2.
            yn = func(xn)
            if cmp(yn,target) == cmp(y0,target):
               x0,y0 = xn,yn
            else:
               x1,y1 = xn,yn
        return x1


From gallium.arsenide at gmail.com  Tue Jul  7 21:26:13 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Tue, 7 Jul 2009 18:26:13 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org> 
	<h30e3t$g56$2@reader1.panix.com> <8763e4ox74.fsf@benfinney.id.au>
Message-ID: <197bfc81-05a6-4328-acec-3ddd5b733655@d32g2000yqh.googlegroups.com>

On Jul 7, 8:06?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> I have got very good results from teaching using
> the analogy of ?paper tags tied to physical objects?
> to describe Python's references to values.

Ah, I like that!  I think it's better than what I used in my post
(which I composed and submitted before yours showed up in my reader).

I am not formally a teacher, but I do try to help "nonprogrammers"
learn Python from time to time, and this will be a good one to
remember.

John


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 21:30:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 22:30:07 -0300
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<4A5344BE.2080006@sequans.com>
Message-ID: <op.uwp6ght7x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 09:51:10 -0300, Jean-Michel Pichavant  
<jeanmichel at sequans.com> escribi?:
> I've never used sense in that way before, nor I've seen used by others  
> until now. However Kj is right, and my dictionary seems wrong  
> (wordreference.com). I've searched through others dictionaries and find  
> out this is actually applicable to functions. My bad.

Using a common word with its common meaning is important too in order to  
understand the code. It's hard enough for students to grasp the algorithm  
itself, why make it artificially harder by using strange variable names.

Some years ago I had to endure using an in-house framework with names like  
bring_XXX and fix_XXX instead of the usual names get_XXX and set_XXX (that  
was C++, emulating properties; I'm not sure of the actual verbs used,  
perhaps "obtain" and "establish", but certainly not get/set/put). Add some  
undecipherable comments in spanglish, profuse usage of macros that alter  
the lexical appearance of the language, and even reading code was a  
torture.

-- 
Gabriel Genellina



From fatkinson at mishmash.com  Tue Jul  7 21:45:24 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Tue, 07 Jul 2009 18:45:24 -0700
Subject: IP Address Function
Message-ID: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>

	Is there a Python function I can use to get the user's IP
address so I can display it on his browser?  

	Regards, 




							Fred 


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 21:54:03 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 22:54:03 -0300
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
Message-ID: <op.uwp7kdr9x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 22:45:24 -0300, Fred Atkinson <fatkinson at mishmash.com>  
escribi?:

> 	Is there a Python function I can use to get the user's IP
> address so I can display it on his browser?

There is a long distance between "Python" and "browser" - you'll have to  
tell us what is in between the two.
By example, do you have a server and the user connects to it? is it  
running Python? how do you run the Python application?
And why do you want to do that on the server side? Isn't easier to do that  
on the client side? What about proxies? NAT?

If using CGI, look at the REMOTE_ADDR environment variable.

-- 
Gabriel Genellina



From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 22:03:16 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 02:03:16 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
	<h30e3t$g56$2@reader1.panix.com>
Message-ID: <006fd94e$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 21:18:53 +0000, kj wrote:

> I had not realized how *profoundly* different the meaning of the "=" in
> Python's
> 
>   spam = ham
> 
> is from the "=" in its
> 
>   spam[3] = ham[3]
> 
> So much for "explicit is better than implicit"...

I'm sorry, I don't get it. Can you explain please? I don't see why it's 
so "profoundly" different. Apart from spam[3] = x not being permitted if 
spam is an immutable type.

I suppose though they are *fundamentally* different, in that spam=ham is 
dealt with by the compiler while spam[3]=ham is handled by the object 
spam using the __setitem__ method. Is that the difference you're talking 
about?


-- 
Steven


From python at bdurham.com  Tue Jul  7 22:40:05 2009
From: python at bdurham.com (python at bdurham.com)
Date: Tue, 07 Jul 2009 22:40:05 -0400
Subject: tough-to-explain Python
In-Reply-To: <197bfc81-05a6-4328-acec-3ddd5b733655@d32g2000yqh.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
	<h30e3t$g56$2@reader1.panix.com> <8763e4ox74.fsf@benfinney.id.au>
	<197bfc81-05a6-4328-acec-3ddd5b733655@d32g2000yqh.googlegroups.com>
Message-ID: <1247020805.1725.1324003095@webmail.messagingengine.com>

Ben,

> I have got very good results from teaching using the analogy of "paper tags tied to physical objects" to describe Python's references to values.

Great analogy!! And an excellent analogy for newcomers to Python. (this
would have saved me some personal pain in my early days).

Regards,
Malcolm


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 23:02:53 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 08 Jul 2009 00:02:53 -0300
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <op.uwp22gpmx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 17:04:46 -0300, kj <no.email at please.post> escribi?:

> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
>>>> ham = [1, 2, 3, 4]
>>>> spam = (ham,)
>>>> spam
> ([1, 2, 3, 4],)
>>>> spam[0] is ham
> True
>>>> spam[0] += [5]
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
>>>> ham += [5]
>>>> spam
> ([1, 2, 3, 4, 5, 5],)

>
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.

This article is based on an old thread in this list that is very
enlightening:

How To Think Like A Pythonista
http://python.net/crew/mwh/hacks/objectthink.html

and I'll quote just a paragraph from Alex Martelli:

?There is [...] a huge difference
between changing an object, and changing (mutating) some
OTHER object to which the first refers.

In Bologna over 100 years ago we had a statue of a local hero
depicted pointing forwards with his finger -- presumably to
the future, but given where exactly it was placed, the locals
soon identified it as "the statue that points to Hotel
Belfiore".  Then one day some enterprising developer bought
the hotel's building and restructured it -- in particular,
where the hotel used to be was now a restaurant, Da Carlo.

So, "the statue that points to Hotel Belfiore" had suddenly
become "the statue that points to Da Carlo"...!  Amazing
isn't it?  Considering that marble isn't very fluid and the
statue had not been moved or disturbed in any way...?

This is a real anecdote, by the way (except that I'm not
sure of the names of the hotel and restaurant involved --
I could be wrong on those), but I think it can still help
here.  The dictionary, or statue, has not changed at all,
even though the objects it refers/points to may have been
mutated beyond recognition, and the name people know it
by (the dictionary's string-representation) may therefore
change.  That name or representation was and is referring
to a non-intrinsic, non-persistent, "happenstance"
characteristic of the statue, or dictionary...?

-- 
Gabriel Genellina



From peter.milliken at gmail.com  Tue Jul  7 23:18:20 2009
From: peter.milliken at gmail.com (Peter)
Date: Tue, 7 Jul 2009 20:18:20 -0700 (PDT)
Subject: How to use Python to interface with Web pages?
Message-ID: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>

Any help would be appreciated :-)

I want to write an auction sniping tool in Python. I know Python, but
I know absolutely nothing about web pages, javascript etc i.e. I want
the program to automatically log me into my eBay account, access the
appropriate item, locate how many mins/seconds until the bid time ends
and then automatically place a bid at the last possible moment.

I can see the web-page source - it looks to be javascript (to my
untutored eye :-)).

But how do I enter data and "simulated" mouse presses on a web-page
that I have accessed via a Python program?

So where can I start to learn how to do this? Any books available? web
resources that show examples or offer tutorials?

I have (in the past) written some python to scoop data off web-sites
but I have never written anything that interactively interacts with
the web-page contents and don't know where to even start on this one.

Thanks for any help/pointers

Peter


From ralf at schoenian-online.de  Wed Jul  8 00:05:53 2009
From: ralf at schoenian-online.de (Ralf Schoenian)
Date: Wed, 08 Jul 2009 06:05:53 +0200
Subject: How to use Python to interface with Web pages?
In-Reply-To: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
References: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
Message-ID: <4A541B21.3030203@schoenian-online.de>

Peter wrote:
> Any help would be appreciated :-)
> 
> I want to write an auction sniping tool in Python. I know Python, but
> I know absolutely nothing about web pages, javascript etc i.e. I want
> the program to automatically log me into my eBay account, access the
> appropriate item, locate how many mins/seconds until the bid time ends
> and then automatically place a bid at the last possible moment.
> 
> I can see the web-page source - it looks to be javascript (to my
> untutored eye :-)).
> 
> But how do I enter data and "simulated" mouse presses on a web-page
> that I have accessed via a Python program?
> 
> So where can I start to learn how to do this? Any books available? web
> resources that show examples or offer tutorials?
> 
> I have (in the past) written some python to scoop data off web-sites
> but I have never written anything that interactively interacts with
> the web-page contents and don't know where to even start on this one.
> 
> Thanks for any help/pointers
> 
> Peter

Hi,

a good starting point possibly is 
http://wwwsearch.sourceforge.net/mechanize/

Regards,
Ralf


From sajmikins at gmail.com  Wed Jul  8 00:10:38 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 21:10:38 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>

On Jul 7, 4:04 pm, kj <no.em... at please.post> wrote:
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
> Consider the following interaction sequence:
>
> >>> def eggs(some_int, some_list, some_tuple):
>
> ...     some_int += 2
> ...     some_list += [2]
> ...     some_tuple += (2,)
> ...
>
> >>> x = 42
> >>> y = (42,)
> >>> z = [42]
> >>> eggs(x, y, z)
> >>> x
> 42
> >>> y
> (42,)
> >>> z
> [42, 2]

You have transposed some_list and some some_tuple. I.e. you should be
calling eggs(x, z, y).

> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?

You don't. Rank beginners don't have enough background knowledge to
grok that code.

Why would you even tell the poor bastards about "+=" before they were
comfortable with (python's style of) function calls, immutable
integers, mutable lists and immutable tuples?

Let them use "x = x + y" until they have enough knowledge to
understand "augmented" assignment.

Syntax matters (I mean general order of things, not linguistic
syntax.)  Making an omelette requires putting eggs in a pan and
cracking them, but not in that order.

> Or consider this one:
>
> >>> ham = [1, 2, 3, 4]
> >>> spam = (ham,)
> >>> spam
> ([1, 2, 3, 4],)
> >>> spam[0] is ham
> True
> >>> spam[0] += [5]
>
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
> >>> ham += [5]
> >>> spam
>
> ([1, 2, 3, 4, 5, 5],)
>
>
>
> What do you say to that?

I say, "Don't use augmented assignment with indexed tuples."

Seriously, python's augmented assignment is almost magical. I think
you're just making trouble for yourself and your students if you
introduce it too early.

I get python pretty well (if I say so myself) but I wouldn't know how
to explain:

In [1]: def foo(a_list):
   ...:     a_list = a_list + [5]
   ...:
   ...:

In [2]: n = []

In [3]: foo(n)

In [4]: n
Out[4]: []

In [5]: def bar(a_list):
   ...:     a_list += [5]
   ...:
   ...:

In [6]: bar(n)

In [7]: n
Out[7]: [5]


It's "Just The Way It Is". Freakin' magic, man.

> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!

Frankly, I'm of the impression that it's a mistake not to start
teaching programming with /the bit/ and work your way up from there.
I'm not kidding. I wrote a (draft) article about this: "Computer
Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4

I really think the only good way to teach computers and programming is
to start with a bit, and build up from there. "Ontology recapitulates
phylogeny"

I realize that doesn't help you teach python, but I wanted to put it
out there.


From sjmachin at lexicon.net  Wed Jul  8 00:30:26 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 7 Jul 2009 21:30:26 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
Message-ID: <bb395e02-fe33-441e-8c01-27db196ef8e7@d9g2000prh.googlegroups.com>

On Jul 8, 3:05?am, dana <dana_at_w... at yahoo.com> wrote:
> I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
> modules together. Although I don't have Python 2.5, I've been informed
> the DBI module has been deprecated at 2.5.
>
> A few questions:
>
> 1) Although deprecated, will it work at all in 2.5? Does the fact that
> it is deprecrated mean it has been removed entirely, or does Python
> 2.5 simply issuing a warning?

Deprecated certainly doesn't mean removed.

>
> 2) What do I use in place of DBI for my Python 2.4. scripts that
> import modules DBI and ODBC together. I don't use DBI directly. It was
> simply a dependency for the ODBC module as best I knew.

For a start, none of (DBI, ODBC, dbi, odbc) are standard Python-
supplied modules. Perhaps you are referring to the odbc (and dbi) from
the pywin32 package? Where did you get them from? If you can't
remember, try this:

|Python 2.4.4 (#71, Oct 18 2006, 08:34:43) [MSC v.1310 32 bit (Intel)]
on win32
| Type "help", "copyright", "credits" or "license" for more
information.
| >>> import odbc
| >>> odbc.__file__
| 'C:\\python24\\lib\\site-packages\\win32\\odbc.pyd'
| >>>

If this is what you're talking about, you should be asking on the
pywin32 dicussion list (http://mail.python.org/mailman/listinfo/python-
win32).

General advice: if you are thinking of upgrading your Python version,
go straight to 2.6. odbc is AFAIK stuck at version 1.0 of the Python
DB API; consider switching to pyodbc (http://code.google.com/p/
pyodbc/)

HTH,
John


From rajat.dudeja at gmail.com  Wed Jul  8 00:31:12 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Tue, 7 Jul 2009 21:31:12 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
Message-ID: <e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>

On Jul 8, 4:57?am, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>
> Heimes wrote:
> > By the way most operating systems don't lock a file when it's opened for
> > reading or writing or even executed.
>
> The general conclusion seems to be that mandatory locking is more trouble
> than it's worth.

My OS is a windows XP sp3. All I'm trying to achieve is to close an
application ( which could be a notepad, a wordpad or some other text
editor) that have opened my file. Once the file is closed I can easily
delete that file.

I guess, if file is opened by one of that application, the file must
be locked and so is the reason I cannot delete the file.

Please suggest if this is fine.



From timr at probo.com  Wed Jul  8 01:11:12 2009
From: timr at probo.com (Tim Roberts)
Date: Tue, 07 Jul 2009 22:11:12 -0700
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
Message-ID: <0ca855t29jklb0o0gi31ourfk3lstdiepf@4ax.com>

Nobody <nobody at nowhere.com> wrote:
>
>The webcam is bound to do some encoding; most of them use USB "full speed"
>(12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.

That's not true.  Most of the web cams made in the last 5 years or so run
at high speed, 480 Mbps.  Full speed only gets you 1 fps at 640x480
uncompressed, so it's really only useful for the most primitive video
conference cams.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 02:09:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 06:09:19 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <007012f9$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 20:04:46 +0000, kj wrote:

> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.

[...]


> Or consider this one:
> 
>>>> ham = [1, 2, 3, 4]
>>>> spam = (ham,)
>>>> spam
> ([1, 2, 3, 4],)
>>>> spam[0] is ham
> True
>>>> spam[0] += [5]
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
>>>> ham += [5]
>>>> spam
> ([1, 2, 3, 4, 5, 5],)
>>>> 
>>>> 
> What do you say to that?


That one surely is very straight forward. Just like the exception says, 
tuples don't support item assignment, so spam[0] += [5] is not allowed.

But just because you have put a list inside a tuple doesn't mean the list 
stops being a list -- you can still append to the list, which is what 
ham += [5] does. So spam is unchanged: it is still the one-item tuple 
containing a list. It is just that the list has now been modified.

This is only troublesome (in my opinion) if you imagine that tuples are 
somehow magical "frozen-lists", where the contents can't be modified once 
created. That's not the case -- the tuple itself can't be modified, but 
the objects inside it remain ordinary objects, and the mutable ones can 
be modified.

The thing to remember is that the tuple spam doesn't know anything about 
the *name* ham -- it knows the object referred to by the name ham. You 
can modify the name, and nothing happens to the tuple:

>>> spam
([1, 2, 3, 4, 5],)
>>> ham = [5]
>>> spam
([1, 2, 3, 4, 5],)

Or if you prefer:

>>> ham = spam[0]  # label the list inside spam as 'ham'
>>> ham += [6]  # modify the list labelled as 'ham'
>>> spam
([1, 2, 3, 4, 5, 6],)
>>> pork = ham  # create a new label, 'pork', and bind it to the same list
>>> del ham  # throw away the label 'ham'
>>> pork += [7]  # modify the list labelled as 'pork'
>>> spam
([1, 2, 3, 4, 5, 6, 7],)


It's all about the objects, not the names.



-- 
Steven


From dhananjay.c.joshi at gmail.com  Wed Jul  8 02:10:59 2009
From: dhananjay.c.joshi at gmail.com (Dhananjay)
Date: Wed, 8 Jul 2009 11:40:59 +0530
Subject: count
Message-ID: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>

Dear all,

I have file as follows,however, tab seperated (not shown in following file):

     6       3       4.309726
     7       65     93.377388
     8       47     50.111952
     9       270   253.045923
     10     184    182.684670
     11     76     121.853455
     12     85     136.283470
     13     114    145.910662
     14     45      80.703013
     15     44      47.154646
     16     41      66.461339
     17     16      33.819488
     18     127     136.105455
     19     70      88.798681
     20     29      61.297823


I wanted to sort column 2 in assending order  and I read whole file in array
"data" and did the following:

data.sort(key = lambda fields:(fields[2]))

I have sorted column 2, however I want to count the numbers in the column 2.
i.e. I want to know, for example, how many repeates of say '3' (first row,
2nd column in above data) are there in column 2.

I could write seperate programme to get the result.s.

However, is there any way to count the numbers there itself while sorting in
column 2 ?


Thanking you in advance,


-- Dhananjay
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/507f91f3/attachment.html>

From romeoamp at gmail.com  Wed Jul  8 02:13:42 2009
From: romeoamp at gmail.com (romeoamp)
Date: Tue, 7 Jul 2009 23:13:42 -0700 (PDT)
Subject: SSH utility
In-Reply-To: <a47bf8f1-7889-4ad2-bc49-f04c8487e3e2@r15g2000prh.googlegroups.com>
References: <b41c8ad7-e286-4147-893c-c7b2adffe73a@b30g2000prf.googlegroups.com>
	<a47bf8f1-7889-4ad2-bc49-f04c8487e3e2@r15g2000prh.googlegroups.com>
Message-ID: <24385961.post@talk.nabble.com>


Please look at on :


http://www.lag.net/paramiko/ http://www.lag.net/paramiko/ 


Sample Code: Find Attachment


Thanks,
S.V.RAJKUMAR,
XOU Solutions India Private Limited
No. 37, PM Towers,
Greams Road,
Thousand Lights,
Chennai - 6 .
Mobile No : +91 - 9940632275. 





half.italian wrote:
> 
> On Aug 11, 5:17?am, Edwin.Mad... at VerizonWireless.com wrote:
>> for similar tasks, I use pexpecthttp://pypi.python.org/pypi/pexpect.
>>
>> spawning bash process and simulate an interactive session. Here sending
>> ls command, retrieving results and exiting. In the spawned process ssh or
>> any other command, is just another command.
>>
>> ------------actual session--------------------------
>> $ python
>> Python 2.5.1 (r251:54863, May 18 2007, 16:56:43)
>> [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
>> Type "help", "copyright", "credits" or "license" for more information.>>>
>> import pexpect
>> >>> c = pexpect.spawn('/bin/bash')
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('\x1b[?1034hmadared at NJWARHQD0IT696A:~\r\n', '$ ')>>> c.sendline('ls')
>> 3
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('ls\r\x.txt ?xx.txt ?xy.txt ?y.txt\r\nmadared at NJWARHQD0IT696A:~\r\n', '$
>> ')>>> c.sendline('exit')
>> 5
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 1
>> >>> c.before, c.after
>>
>> ('exit\r\nexit\r\n', )>>> exit()
>>
>> madared at NJWARHQD0IT696A:~
>> $
>> ---------------------------------------------------------------
>>
>> hope that helps.
>>
>> regards.
>> Edwin
>>
>> -----Original Message-----
>> From: python-list-bounces+edwin.madari=verizonwireless.... at python.org
>>
>> [mailto:python-list-bounces+edwin.madari=verizonwireless.... at python.org]
>> On Behalf Of James Brady
>> Sent: Monday, August 11, 2008 12:26 AM
>> To: python-l... at python.org
>> Subject: SSH utility
>>
>> Hi all,
>> I'm looking for a python library that lets me execute shell commands
>> on remote machines.
>>
>> I've tried a few SSH utilities so far: paramiko, PySSH and pssh;
>> unfortunately all been unreliable, and repeated questions on their
>> respective mailing lists haven't been answered...
>>
>> It seems like the sort of commodity task that there should be a pretty
>> robust library for. Are there any suggestions for alternative
>> libraries or approaches?
>>
>> Thanks!
>> James
>> --http://mail.python.org/mailman/listinfo/python-list
>>
>> The information contained in this message and any attachment may be
>> proprietary, confidential, and privileged or subject to the work
>> product doctrine and thus protected from disclosure. ?If the reader
>> of this message is not the intended recipient, or an employee or
>> agent responsible for delivering this message to the intended
>> recipient, you are hereby notified that any dissemination,
>> distribution or copying of this communication is strictly prohibited.
>> If you have received this communication in error, please notify me
>> immediately by replying to this message and deleting it and all
>> copies and backups thereof. ?Thank you.
> 
> I second pexpect and the nice little module that comes with it
> ssh_session.py.
> 
> Been using it for ages now!
> 
> ~Sean
> --
> http://mail.python.org/mailman/listinfo/python-list
> 
> 
http://www.nabble.com/file/p24385961/sshclient.py sshclient.py 
-- 
View this message in context: http://www.nabble.com/SSH-utility-tp18920030p24385961.html
Sent from the Python - python-list mailing list archive at Nabble.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/c8b70a94/attachment.html>

From romeoamp at gmail.com  Wed Jul  8 02:15:08 2009
From: romeoamp at gmail.com (romeoamp)
Date: Tue, 7 Jul 2009 23:15:08 -0700 (PDT)
Subject: SSH utility
Message-ID: <24385961.post@talk.nabble.com>


Please look at on :


http://www.lag.net/paramiko/

Sample Code: Find Attachment


Thanks,
S.V.RAJKUMAR,
XOU Solutions India Private Limited
No. 37, PM Towers,
Greams Road,
Thousand Lights,
Chennai - 6 .
Mobile No : +91 - 9940632275. 



half.italian wrote:
> 
> On Aug 11, 5:17?am, Edwin.Mad... at VerizonWireless.com wrote:
>> for similar tasks, I use pexpecthttp://pypi.python.org/pypi/pexpect.
>>
>> spawning bash process and simulate an interactive session. Here sending
>> ls command, retrieving results and exiting. In the spawned process ssh or
>> any other command, is just another command.
>>
>> ------------actual session--------------------------
>> $ python
>> Python 2.5.1 (r251:54863, May 18 2007, 16:56:43)
>> [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
>> Type "help", "copyright", "credits" or "license" for more information.>>>
>> import pexpect
>> >>> c = pexpect.spawn('/bin/bash')
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('\x1b[?1034hmadared at NJWARHQD0IT696A:~\r\n', '$ ')>>> c.sendline('ls')
>> 3
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('ls\r\x.txt ?xx.txt ?xy.txt ?y.txt\r\nmadared at NJWARHQD0IT696A:~\r\n', '$
>> ')>>> c.sendline('exit')
>> 5
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 1
>> >>> c.before, c.after
>>
>> ('exit\r\nexit\r\n', <class 'pexpect.EOF'>)>>> exit()
>>
>> madared at NJWARHQD0IT696A:~
>> $
>> ---------------------------------------------------------------
>>
>> hope that helps.
>>
>> regards.
>> Edwin
>>
>> -----Original Message-----
>> From: python-list-bounces+edwin.madari=verizonwireless.... at python.org
>>
>> [mailto:python-list-bounces+edwin.madari=verizonwireless.... at python.org]
>> On Behalf Of James Brady
>> Sent: Monday, August 11, 2008 12:26 AM
>> To: python-l... at python.org
>> Subject: SSH utility
>>
>> Hi all,
>> I'm looking for a python library that lets me execute shell commands
>> on remote machines.
>>
>> I've tried a few SSH utilities so far: paramiko, PySSH and pssh;
>> unfortunately all been unreliable, and repeated questions on their
>> respective mailing lists haven't been answered...
>>
>> It seems like the sort of commodity task that there should be a pretty
>> robust library for. Are there any suggestions for alternative
>> libraries or approaches?
>>
>> Thanks!
>> James
>> --http://mail.python.org/mailman/listinfo/python-list
>>
>> The information contained in this message and any attachment may be
>> proprietary, confidential, and privileged or subject to the work
>> product doctrine and thus protected from disclosure. ?If the reader
>> of this message is not the intended recipient, or an employee or
>> agent responsible for delivering this message to the intended
>> recipient, you are hereby notified that any dissemination,
>> distribution or copying of this communication is strictly prohibited.
>> If you have received this communication in error, please notify me
>> immediately by replying to this message and deleting it and all
>> copies and backups thereof. ?Thank you.
> 
> I second pexpect and the nice little module that comes with it
> ssh_session.py.
> 
> Been using it for ages now!
> 
> ~Sean
> --
> http://mail.python.org/mailman/listinfo/python-list
> 
> 
http://www.nabble.com/file/p24385961/sshclient.py sshclient.py 
-- 
View this message in context: http://www.nabble.com/SSH-utility-tp18920030p24385961.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From python at rcn.com  Wed Jul  8 03:11:50 2009
From: python at rcn.com (Raymond Hettinger)
Date: Wed, 8 Jul 2009 00:11:50 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
Message-ID: <0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>

[Scott David Daniels]
> def most_frequent(arr, N):
> ? ? ?'''Return the top N (freq, val) elements in arr'''
> ? ? ?counted = frequency(arr) # get an iterator for freq-val pairs
> ? ? ?heap = []
> ? ? ?# First, just fill up the array with the first N distinct
> ? ? ?for i in range(N):
> ? ? ? ? ?try:
> ? ? ? ? ? ? ?heap.append(counted.next())
> ? ? ? ? ?except StopIteration:
> ? ? ? ? ? ? ?break # If we run out here, no need for a heap
> ? ? ?else:
> ? ? ? ? ?# more to go, switch to a min-heap, and replace the least
> ? ? ? ? ?# element every time we find something better
> ? ? ? ? ?heapq.heapify(heap)
> ? ? ? ? ?for pair in counted:
> ? ? ? ? ? ? ?if pair > heap[0]:
> ? ? ? ? ? ? ? ? ?heapq.heapreplace(heap, pair)
> ? ? ?return sorted(heap, reverse=True) # put most frequent first.

In Py2.4 and later, see heapq.nlargest().
In Py3.1, see collections.Counter(data).most_common(n)


Raymond


From wuwei23 at gmail.com  Wed Jul  8 03:29:32 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 8 Jul 2009 00:29:32 -0700 (PDT)
Subject: How to use Python to interface with Web pages?
References: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
Message-ID: <127e0a78-89fc-4c09-bda7-95836c57ac58@v37g2000prg.googlegroups.com>

On Jul 8, 1:18?pm, Peter <peter.milli... at gmail.com> wrote:
> I can see the web-page source - it looks to be javascript (to my
> untutored eye :-)).
>
> But how do I enter data and "simulated" mouse presses on a web-page
> that I have accessed via a Python program?
> [...]
> I have (in the past) written some python to scoop data off web-sites
> but I have never written anything that interactively interacts with
> the web-page contents and don't know where to even start on this one.

I don't have much experience with it, but for interacting with
javascript-heavy pages you might want to take a look at Selenium:

http://seleniumhq.org/
http://pypi.python.org/pypi/selenium
http://jimmyg.org/blog/2009/getting-started-with-selenium-and-python.html
http://joker.linuxstuff.pl/documentation/make_selenium

It's primarily aimed at testing web app UIs, but if it allows for
values to be passed into tests then 'test' == 'action' in terms of
your requirements.

Hope this helps.

- alex23


From bieffe62 at gmail.com  Wed Jul  8 03:32:07 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Wed, 8 Jul 2009 00:32:07 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <70654e24-aa1b-4a78-87a3-d36873da6109@i6g2000yqj.googlegroups.com>

On Jul 7, 10:04?pm, kj <no.em... at please.post> wrote:
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
> Consider the following interaction sequence:
>
> >>> def eggs(some_int, some_list, some_tuple):
>
> ... ? ? some_int += 2
> ... ? ? some_list += [2]
> ... ? ? some_tuple += (2,)
> ...
>
> >>> x = 42
> >>> y = (42,)
> >>> z = [42]
> >>> eggs(x, y, z)
> >>> x
> 42
> >>> y
> (42,)
> >>> z
> [42, 2]
>
> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?
>
> Or consider this one:
>
> >>> ham = [1, 2, 3, 4]
> >>> spam = (ham,)
> >>> spam
> ([1, 2, 3, 4],)
> >>> spam[0] is ham
> True
> >>> spam[0] += [5]
>
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment>>> ham += [5]
> >>> spam
>
> ([1, 2, 3, 4, 5, 5],)
>
>
>
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!
>
> TIA!
>
> kj

I would go with something like this:

"""
In object oriented programming, the same function or operator can be
used to represent
different things. This is called overloading. To understand what the
operator/function do, we have to look at
the kind of object it is applied to.
In this case, the operator "+=" means two different things:
- for strings and numbers it means : "create a new object by merging
the two operands". This is why the original object is left the same.
- for lists, it means : "increase the left operand with the contents
of the right operand". This is why the original object is changed
"""

You couuld also add:
"""
You see, in python everithing is an object. Some object can be changed
(mutable objects), others cannot.
"""
but this is another story.


P:S : Sometime I think they should not have allowed += on immutables
and forced everybody to write s = s + "some more".

Ciao
----
FB


From mail at timgolden.me.uk  Wed Jul  8 03:45:58 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 08 Jul 2009 08:45:58 +0100
Subject: Check file is locked?
In-Reply-To: <e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
Message-ID: <4A544EB6.5090404@timgolden.me.uk>

Rajat wrote:
> On Jul 8, 4:57 am, Lawrence D'Oliveiro <l... at geek-
> central.gen.new_zealand> wrote:
>> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>>
>> Heimes wrote:
>>> By the way most operating systems don't lock a file when it's opened for
>>> reading or writing or even executed.
>> The general conclusion seems to be that mandatory locking is more trouble
>> than it's worth.
> 
> My OS is a windows XP sp3. All I'm trying to achieve is to close an
> application ( which could be a notepad, a wordpad or some other text
> editor) that have opened my file. Once the file is closed I can easily
> delete that file.
> 
> I guess, if file is opened by one of that application, the file must
> be locked and so is the reason I cannot delete the file.


I assume that your real requirement is: I can't open/close/delete
this file; it must be locked by something else; what is that
something else?

The simplest thing is probably to run sysinternals' handle util:

  http://technet.microsoft.com/en-us/sysinternals/bb896655.aspx

and use the subprocess module to parse the output.
That will give you the pid, and you can then use, eg, psutil:

  http://code.google.com/p/psutil/

to get the details of the process.

TJG


From piet at cs.uu.nl  Wed Jul  8 04:11:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 10:11:35 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
Message-ID: <m2hbxnbnm0.fsf@cs.uu.nl>

>>>>> Simon Forman <sajmikins at gmail.com> (SF) wrote:

>SF> Why would you even tell the poor bastards about "+=" before they were
>SF> comfortable with (python's style of) function calls, immutable
>SF> integers, mutable lists and immutable tuples?

>SF> Let them use "x = x + y" until they have enough knowledge to
>SF> understand "augmented" assignment.

And *then* you can tell them that "x += y" can be subtly different from 
"x = x + y", which is what happened in the example that the OP gave.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From gagsl-py2 at yahoo.com.ar  Wed Jul  8 04:13:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 08 Jul 2009 05:13:42 -0300
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<70654e24-aa1b-4a78-87a3-d36873da6109@i6g2000yqj.googlegroups.com>
Message-ID: <op.uwqo44t2x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 04:32:07 -0300, Francesco Bochicchio  
<bieffe62 at gmail.com> escribi?:

> I would go with something like this:
>
> """
> In object oriented programming, the same function or operator can be
> used to represent
> different things. This is called overloading. To understand what the
> operator/function do, we have to look at
> the kind of object it is applied to.
> In this case, the operator "+=" means two different things:
> - for strings and numbers it means : "create a new object by merging
> the two operands". This is why the original object is left the same.
> - for lists, it means : "increase the left operand with the contents
> of the right operand". This is why the original object is changed
> """

Mmm, but this isn't quite exact. += isn't an operator, but a statement  
(augmented assignment). a += b translates to: [*]

a = a.__iadd__(b) [*]

It's up to the __iadd__ implementation to return the same object or a new  
one, and the assignment occurs even if the same object is returned.

If you think of an assignments as binding names to objects (well, that's  
the documented behavior, btw) things become more clear.

> P:S : Sometime I think they should not have allowed += on immutables
> and forced everybody to write s = s + "some more".

I think not everyone agreed when += was introduced.
But now, having s += "some more" allows the operation to be optimized.

[*] except 'a' is evaluated only once

-- 
Gabriel Genellina



From helvinlui at gmail.com  Wed Jul  8 04:51:07 2009
From: helvinlui at gmail.com (Helvin)
Date: Wed, 8 Jul 2009 01:51:07 -0700 (PDT)
Subject: PyQt GUI
Message-ID: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>

Hi experts!

I'm developing a GUI for a software using PyQT, and need 3D
visualization. Should I use PyOpenGL or VTK?
I understand that the PyQt package comes with a opengl module. What
else would I need? I think I need to download opengl. but how? where?
I have VTK and pyVTK installed, but I don't know how to use it in my
code, as when I run it, an error says it can't find the vtk module.

Help would be sooooo appreciated!
Helvin


From fatkinson at mishmash.com  Wed Jul  8 04:55:29 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Wed, 08 Jul 2009 01:55:29 -0700
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
Message-ID: <jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>

On Tue, 07 Jul 2009 22:54:03 -0300, "Gabriel Genellina"
<gagsl-py2 at yahoo.com.ar> wrote:

>En Tue, 07 Jul 2009 22:45:24 -0300, Fred Atkinson <fatkinson at mishmash.com>  
>escribi?:
>
>> 	Is there a Python function I can use to get the user's IP
>> address so I can display it on his browser?
>
>There is a long distance between "Python" and "browser" - you'll have to  
>tell us what is in between the two.

	I want to have a Web page come up (written in Python, cgi)
that returns the IP address of the browser (user's PC's IP address).  

>By example, do you have a server and the user connects to it? is it  
>running Python? how do you run the Python application?
>And why do you want to do that on the server side? Isn't easier to do that  
>on the client side? What about proxies? NAT?

	Yes.  By CGI.  

>If using CGI, look at the REMOTE_ADDR environment variable.

	I did look at REMOTE_ADDR but I've been unable to figure out
the correct way to code it.  I've tried a number of ways but I've been
unsuccessful.  

	Ideally, I'd like to store the brower's IP address in a string
and then print the string on the Web page from a Python CGI script.  

	Regards, 



						Fred 


From vilya.harvey at gmail.com  Wed Jul  8 04:56:55 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Wed, 8 Jul 2009 09:56:55 +0100
Subject: count
In-Reply-To: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
Message-ID: <6aef848f0907080156k114b0bb0me13b26904683d411@mail.gmail.com>

2009/7/8 Dhananjay <dhananjay.c.joshi at gmail.com>:
> I wanted to sort column 2 in assending order? and I read whole file in array
> "data" and did the following:
>
> data.sort(key = lambda fields:(fields[2]))
>
> I have sorted column 2, however I want to count the numbers in the column 2.
> i.e. I want to know, for example, how many repeates of say '3' (first row,
> 2nd column in above data) are there in column 2.

One thing: indexes in Python start from 0, so the second column has an
index of 1 not 2. In other words, it should be data.sort(key = lambda
fields: fields[1]) instead.

With that out of the way, the following will print out a count of each
unique item in the second column:

from itertools import groupby
for x, g in groupby([fields[1] for fields in data]):
    print x, len(tuple(g))

Hope that helps,
Vil.


From deets at nospam.web.de  Wed Jul  8 05:11:51 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 08 Jul 2009 11:11:51 +0200
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
Message-ID: <7bj5ulF22b4ktU1@mid.uni-berlin.de>

Helvin wrote:

> Hi experts!
> 
> I'm developing a GUI for a software using PyQT, and need 3D
> visualization. Should I use PyOpenGL or VTK?
> I understand that the PyQt package comes with a opengl module. What
> else would I need? I think I need to download opengl. but how? where?
> I have VTK and pyVTK installed, but I don't know how to use it in my
> code, as when I run it, an error says it can't find the vtk module.

VTK won't mix with Qt. And I don't think you need to download opengl - it
either comes with your system (or gfx-drivers), or not. I'm not sure if Qt
actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
PyOpenGL I guess.

Diez


From phil at riverbankcomputing.com  Wed Jul  8 05:23:10 2009
From: phil at riverbankcomputing.com (Phil Thompson)
Date: Wed, 08 Jul 2009 10:23:10 +0100
Subject: PyQt GUI
In-Reply-To: <7bj5ulF22b4ktU1@mid.uni-berlin.de>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
Message-ID: <66fe05cfa1805aef3a0d4aadc4e7c9c1@localhost>

On Wed, 08 Jul 2009 11:11:51 +0200, "Diez B. Roggisch"
<deets at nospam.web.de>
wrote:
> Helvin wrote:
> 
>> Hi experts!
>> 
>> I'm developing a GUI for a software using PyQT, and need 3D
>> visualization. Should I use PyOpenGL or VTK?
>> I understand that the PyQt package comes with a opengl module. What
>> else would I need? I think I need to download opengl. but how? where?
>> I have VTK and pyVTK installed, but I don't know how to use it in my
>> code, as when I run it, an error says it can't find the vtk module.
> 
> VTK won't mix with Qt. And I don't think you need to download opengl - it
> either comes with your system (or gfx-drivers), or not. I'm not sure if
Qt
> actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
> PyOpenGL I guess.

VTK has explicit support for both Qt (ie. via C++) and PyQt.

Phil


From eckhardt at satorlaser.com  Wed Jul  8 05:24:28 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Wed, 08 Jul 2009 11:24:28 +0200
Subject: Fractions as result from divisions (was: Re: tough-to-explain Python)
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
Message-ID: <c75ei6-e0i.ln1@satorlaser.homedns.org>

Bearophile wrote:
> For example a novice wants to see 124 / 38 to return the 62/19
> fraction and not 3 or 3.263157894736842 :-)

Python has adopted the latter of the three for operator / and the the second
one for operator //. I wonder if it was considered to just return a
fraction from that operation.

 x = 3/5
 -> x = fraction(3, 5)
 x = x*7
 -> x = fraction(21, 5)
 x = x/2
 -> x = fraction(21, 10)
 range(x)
 -> error, x not an integer
 range(int(x))
 -> [0, 1,]
 y = float(x)
 -> y = 2.1

This would have allowed keeping the operator what people are used to. On the
other hand, implicit conversion to either of float or int would have been
avoided, which is usually the #1 cause for subtle problems.


Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From davea at ieee.org  Wed Jul  8 05:35:54 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 08 Jul 2009 05:35:54 -0400
Subject: Python Error from Apress book
In-Reply-To: <op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
References: <24364269.post@talk.nabble.com>	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>	<4A5345B1.8050306@ieee.org>
	<op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A54687A.6010004@ieee.org>



Gabriel Genellina wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">En Tue, 
> 07 Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
>> Gabriel Genellina wrote:
>>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com> 
>>> escribi?:
>
>>>> When I try to run the command as outlined in
>>>> the book "simple_markup2.py < test_input.txt > test_output.html i 
>>>> get the
>>>> following error every time.
>>>>
>>>> IOError: [Errno 9] Bad file descriptor
>>>
>>> That's a Windows problem. When you execute the script as itself 
>>> (either as you do in the command line, or by double-clicking on it), 
>>> it doesn't have valid standard handles.
>>> You have to invoke Python explicitely:
>>>
>>> python simple_markup2.py < test_input.txt > test_output.html
>>>
>>> (you may need to specify the full path to python.exe, or add the 
>>> directory where Python is installed to your system PATH).
>>>
>> I use stdout this way all the time, with no problem (python 2.6, 
>> Windows XP).  But as you point out, stdin redirection doesn't seem to 
>> work using the file associations.  I do get a different error though. 
>> When I look at sys.stdin, it shows an open file, with handle of zero, 
>> as expected.  But when I do a raw_input(), it gets:
>>      EOFError: EOF when reading a line
>
> I think the error depends on the specific OS version/service pack. But 
> at least on XP this appears to fix it:
>
> http://support.microsoft.com/kb/321788/en-us
>
Thanks for the link.  Looking at that one, it indicates that Windows 
2000 fixed it in SP4, and XP fixed it in Sp1.  But I'm already running 
XP SP3, so I wonder if it's something new.

Matt, what OS version are you running, and exactly what is happening 
when the error occurs?  (you should be able to figure that out from the 
stack trace)


DaveA


From deets at nospam.web.de  Wed Jul  8 05:44:15 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 08 Jul 2009 11:44:15 +0200
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org>
Message-ID: <7bj7reF23oparU1@mid.uni-berlin.de>

Phil Thompson wrote:

> On Wed, 08 Jul 2009 11:11:51 +0200, "Diez B. Roggisch"
> <deets at nospam.web.de>
> wrote:
>> Helvin wrote:
>> 
>>> Hi experts!
>>> 
>>> I'm developing a GUI for a software using PyQT, and need 3D
>>> visualization. Should I use PyOpenGL or VTK?
>>> I understand that the PyQt package comes with a opengl module. What
>>> else would I need? I think I need to download opengl. but how? where?
>>> I have VTK and pyVTK installed, but I don't know how to use it in my
>>> code, as when I run it, an error says it can't find the vtk module.
>> 
>> VTK won't mix with Qt. And I don't think you need to download opengl - it
>> either comes with your system (or gfx-drivers), or not. I'm not sure if
> Qt
>> actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
>> PyOpenGL I guess.
> 
> VTK has explicit support for both Qt (ie. via C++) and PyQt.

Oh, I'm sorry for the FUD - they talk about Tk on their homepage.

Diez


From python.list at tim.thechases.com  Wed Jul  8 05:53:02 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Wed, 08 Jul 2009 04:53:02 -0500
Subject: count
In-Reply-To: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
Message-ID: <4A546C7E.503@tim.thechases.com>

> I wanted to sort column 2 in assending order  and I read whole file in array
> "data" and did the following:
> 
> data.sort(key = lambda fields:(fields[2]))
> 
> I have sorted column 2, however I want to count the numbers in the column 2.
> i.e. I want to know, for example, how many repeates of say '3' (first row,
> 2nd column in above data) are there in column 2.

I think you're trying to count in the wrong step -- I'd do the 
counting while you read the file in; not while you're trying to 
sort.  Maybe something like this untested file-wrapper:

   class Histo:
     def __init__(self, data, column):
       self.data = data
       self.column = column
       self.stats = defaultdict(int)
       self.exhausted = False
     def __iter__(self):
       if self.exhausted:
         raise StopIteration("Input exhausted")
       for line in self.data:
         self.stats[line[self.column]] += 1
         yield line
       self.exhausted = True
     def stats_so_far(self):
       return self.stats

   with file('in.txt') as f:
     r = csv.reader(f, delimiter='\t')
     h = Histo(r, 2)
     data = list(h) # slurp up the elements
   print repr(h.stats_so_far())
   data.sort(key = lambda fields: (fields[2]))

-tkc






From davea at ieee.org  Wed Jul  8 06:18:47 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 08 Jul 2009 06:18:47 -0400
Subject: Check file is locked?
In-Reply-To: <e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
Message-ID: <4A547287.8020507@ieee.org>

Rajat wrote:
> On Jul 8, 4:57 am, Lawrence D'Oliveiro <l... at geek-
> central.gen.new_zealand> wrote:
>   
>> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>>
>> Heimes wrote:
>>     
>>> By the way most operating systems don't lock a file when it's opened for
>>> reading or writing or even executed.
>>>       
>> The general conclusion seems to be that mandatory locking is more trouble
>> than it's worth.
>>     
>
> My OS is a windows XP sp3. All I'm trying to achieve is to close an
> application ( which could be a notepad, a wordpad or some other text
> editor) that have opened my file. Once the file is closed I can easily
> delete that file.
>
> I guess, if file is opened by one of that application, the file must
> be locked and so is the reason I cannot delete the file.
>
> Please suggest if this is fine.
>
>
>   
Neither Wordpad nor Notepad lock the files they have open, at least in 
my experience.  Specifically, I just tried it in XP Sp3.   I created a 
file, opened the file in one of the apps, then deleted the file before 
closing the app.

Word for Windows, on the other hand, has locked files for me in the 
past.  When I tried that one just now (on a text file, because that was 
easy), results were rather confusing.  It let me delete the file, but 
then when I tried to "save" it, it gave me a permissions error.  My 
experience with Winword has been that it's in a world of its own, best 
not messed with.  And this latest version (Office 2007 or somesuch) is 
so modern that it has removed the Help->About menu to make sure I can't 
even tell what version it is.  Next time I rebuild my system, I think 
I'll go back to Office 97.


But perhaps your question is intended to cover the general case.  You 
can get a program from sysinternals called   handle, which will list all 
the files (and other handles) opened by all the processes in the 
system.  You may be able to run that (with subprocess, or just from the 
commandline), and filter its output for the information you want.


DaveA


From dana_at_work at yahoo.com  Wed Jul  8 06:25:33 2009
From: dana_at_work at yahoo.com (dana)
Date: Wed, 8 Jul 2009 03:25:33 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
	<bb395e02-fe33-441e-8c01-27db196ef8e7@d9g2000prh.googlegroups.com>
Message-ID: <084fac41-364f-431c-9b8f-b57c3279f91d@x3g2000yqa.googlegroups.com>

On Jul 8, 12:30?am, John Machin <sjmac... at lexicon.net> wrote:
> Deprecated certainly doesn't mean removed.
> For a start, none of (DBI, ODBC, dbi, odbc) are standard Python-
> supplied modules. Perhaps you are referring to the odbc (and dbi) from
> the pywin32 package? Where did you get them from? If you can't
> remember, try this:

Thanks John. I mean the lower-case dbi and odbc modules from pywin32.
Sorry for being vague. I assumed incorrectly they were part of the
standard library because they came with pywin32.

> If this is what you're talking about, you should be asking on the
> pywin32 dicussion list (http://mail.python.org/mailman/listinfo/python-
> win32).

Thanks again.

> General advice: if you are thinking of upgrading your Python version,
> go straight to 2.6. odbc is AFAIK stuck at version 1.0 of the Python
> DB API; consider switching to pyodbc (http://code.google.com/p/
> pyodbc/)

Thanks thrice.

We "have" to use the version of Python our software vendor supports.
Presently, that's pywin32 version 2.5.

Dana


From piet at cs.uu.nl  Wed Jul  8 06:29:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 12:29:54 +0200
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
Message-ID: <m2d48bbh7h.fsf@cs.uu.nl>

>>>>> Fred Atkinson <fatkinson at mishmash.com> (FA) wrote:

>FA> On Tue, 07 Jul 2009 22:54:03 -0300, "Gabriel Genellina"
>FA> <gagsl-py2 at yahoo.com.ar> wrote:

>>> En Tue, 07 Jul 2009 22:45:24 -0300, Fred Atkinson <fatkinson at mishmash.com>  
>>> escribi?:
>>> 
>>>> Is there a Python function I can use to get the user's IP
>>>> address so I can display it on his browser?
>>> 
>>> There is a long distance between "Python" and "browser" - you'll have to  
>>> tell us what is in between the two.

>FA> 	I want to have a Web page come up (written in Python, cgi)
>FA> that returns the IP address of the browser (user's PC's IP address).  

>>> By example, do you have a server and the user connects to it? is it  
>>> running Python? how do you run the Python application?
>>> And why do you want to do that on the server side? Isn't easier to do that  
>>> on the client side? What about proxies? NAT?

>FA> 	Yes.  By CGI.  

>>> If using CGI, look at the REMOTE_ADDR environment variable.

>FA> 	I did look at REMOTE_ADDR but I've been unable to figure out
>FA> the correct way to code it.  I've tried a number of ways but I've been
>FA> unsuccessful.  

>FA> 	Ideally, I'd like to store the brower's IP address in a string
>FA> and then print the string on the Web page from a Python CGI script.  

Something like:

#! /usr/bin/env python

import cgi
from os import getenv

print "Content-type: text/html"
print

ipaddr = (getenv("HTTP_CLIENT_IP") or
      getenv("HTTP_X_FORWARDED_FOR") or
      getenv("HTTP_X_FORWARDED_FOR") or
      getenv("REMOTE_ADDR") or
      "UNKNOWN")

print ipaddr


-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nick at craig-wood.com  Wed Jul  8 06:30:01 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Wed, 08 Jul 2009 05:30:01 -0500
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
	<006eb2e3$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <slrnh58qbj.mjl.nick@irishsea.home.craig-wood.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
>  On Mon, 06 Jul 2009 15:02:26 -0700, Michael Mossey wrote:
> 
> > On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
> >> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
> >>
> >> > What is required in a python program to make sure it catches a
> >> > control-
> >> > c on the command-line? Do some i/o? The OS here is Linux.
> >>
> >> You can use a try/except to catch a KeyboardInterrupt exception, or you
> >> can trap it using the signal
> >> module:http://docs.python.org/library/signal.html
> >>
> >> You want to trap SIGINT.
> >>
> >> HTH
> >> Philip
> > 
> > Thanks to both of you. However, my question is also about whether I need
> > to be doing i/o or some similar operation for my program to notice in
> > any shape or form that Control-C has been pressed. In the past, I've
> > written Python programs that go about their business ignoring Ctrl-C.
> 
>  I bet that somewhere in your code you have something like:
> 
> 
>  for x in really_big_list:
>      try:
>          long_running_process(x)
>      except:
>          continue
> 
> 
>  If that's what you're doing, stop! The correct way is:
> 
> 
>  for x in really_big_list:
>      try:
>          long_running_process(x)
>      except Exception:
>          # Let KeyboardInterrupt and SystemExit through.
>          continue

Note that it is a relatively recent change (in python 2.5) which made
KeyboardInterrupt not a child of Exception

ncw at dogger:~$ python2.4
Python 2.4.6 (#2, Feb 17 2009, 20:01:48)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
Loaded customisations from '/home/ncw/.pystartup'
>>> isinstance(KeyboardInterrupt(), Exception)
True
>>>

ncw at dogger:~$ python2.5
Python 2.5.4 (r254:67916, Feb 17 2009, 20:16:45)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
Loaded customisations from '/home/ncw/.pystartup'
>>> isinstance(KeyboardInterrupt(), Exception)
False
>>>

>  for x in really_big_list:
>      try:
>          long_running_process(x)
>      except (KeyboardInterrupt, SystemExit):
>          print "User requested exit... shutting down now"
>          cleanup()
>          raise
>      except Exception:
>          continue

That is the backwards compatible way

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From bearophileHUGS at lycos.com  Wed Jul  8 07:20:56 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Wed, 8 Jul 2009 04:20:56 -0700 (PDT)
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com> 
	<mailman.2829.1247043839.8015.python-list@python.org>
Message-ID: <050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>

Vilya Harvey:
> from itertools import groupby
> for x, g in groupby([fields[1] for fields in data]):
> ? ? print x, len(tuple(g))

Avoid that len(tuple(g)), use something like the following, it's lazy
and saves some memory.


def leniter(iterator):
    """leniter(iterator): return the length of a given
    iterator, consuming it, without creating a list.
    Never use it with infinite iterators.

    >>> leniter()
    Traceback (most recent call last):
      ...
    TypeError: leniter() takes exactly 1 argument (0 given)
    >>> leniter([])
    0
    >>> leniter([1])
    1
    >>> leniter(iter([1]))
    1
    >>> leniter(x for x in xrange(100) if x%2)
    50
    >>> from itertools import groupby
    >>> [(leniter(g), h) for h,g in groupby("aaaabccaadeeee")]
    [(4, 'a'), (1, 'b'), (2, 'c'), (2, 'a'), (1, 'd'), (4, 'e')]

    >>> def foo0():
    ...     if False: yield 1
    >>> leniter(foo0())
    0

    >>> def foo1(): yield 1
    >>> leniter(foo1())
    1
    """
    # This code is faster than:  sum(1 for _ in iterator)
    if hasattr(iterator, "__len__"):
        return len(iterator)
    nelements = 0
    for _ in iterator:
        nelements += 1
    return nelements

Bye,
bearophile


From no.email at please.post  Wed Jul  8 07:59:19 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 11:59:19 +0000 (UTC)
Subject: Fractions as result from divisions (was: Re: tough-to-explain
	Python)
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<c75ei6-e0i.ln1@satorlaser.homedns.org>
Message-ID: <h321mn$2bg$1@reader1.panix.com>

In <c75ei6-e0i.ln1 at satorlaser.homedns.org> Ulrich Eckhardt <eckhardt at satorlaser.com> writes:

>Bearophile wrote:
>> For example a novice wants to see 124 / 38 to return the 62/19
>> fraction and not 3 or 3.263157894736842 :-)

>Python has adopted the latter of the three for operator / and the the second
>one for operator //. I wonder if it was considered to just return a
>fraction from that operation.

http://www.python.org/dev/peps/pep-0239/

kj



From mail at microcorp.co.za  Wed Jul  8 08:15:08 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 8 Jul 2009 14:15:08 +0200
Subject: Remoting over SSH
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <007901c9ffc5$cef87780$0d00a8c0@Hendrik>

"Hussein B" <hubaghdadi at gmail.com> wrote:

> Hey,
> I want to perform commands on a remote server over SSH.
> What do I need?
> Thanks.

Access privileges for the remote machine.

- Hendrik





From no.email at please.post  Wed Jul  8 08:23:50 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 12:23:50 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
Message-ID: <h3234l$aod$1@reader1.panix.com>

In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com> Simon Forman <sajmikins at gmail.com> writes:

>Frankly, I'm of the impression that it's a mistake not to start
>teaching programming with /the bit/ and work your way up from there.
>I'm not kidding. I wrote a (draft) article about this: "Computer
>Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4

>I really think the only good way to teach computers and programming is
>to start with a bit, and build up from there. "Ontology recapitulates
>phylogeny"


I happen to be very receptive to this point of view.  I had the
benefit of that sort of training (one of the first computer courses
I took started, believe it or not, with Turing machines, through
coding in machine language, and compiler theory, and all the way
up to dabbling with Unix!), and I suspect that the reason it is
sometimes difficult for me to explain even relatively simple-looking
things to others is that I have this background that I unconsciously,
and incorrectly, take for granted in others...  There is this
persistent idea "out there" that programming is a very accessible
skill, like cooking or gardening, anyone can do it, and even profit
from it, monetarily or otherwise, etc., and to some extent I am
actively contributing to this perception by teaching this course
to non-programmers (experimental biologists to be more precise),
but maybe this idea is not entirely true...  Maybe, to get past
the most amateurish level, one has to, one way or another, come
face-to-face with bits, compilers, algorithms, and all the rest
that real computer scientists learn about in their formal training...

kj



From p.f.moore at gmail.com  Wed Jul  8 08:33:50 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Wed, 8 Jul 2009 13:33:50 +0100
Subject: DBI module deprecated at Python 2.5--what to use in its place?
In-Reply-To: <084fac41-364f-431c-9b8f-b57c3279f91d@x3g2000yqa.googlegroups.com>
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
	<bb395e02-fe33-441e-8c01-27db196ef8e7@d9g2000prh.googlegroups.com>
	<084fac41-364f-431c-9b8f-b57c3279f91d@x3g2000yqa.googlegroups.com>
Message-ID: <79990c6b0907080533v54f97099oabc77a8d146fe5e7@mail.gmail.com>

2009/7/8 dana <dana_at_work at yahoo.com>:
> On Jul 8, 12:30?am, John Machin <sjmac... at lexicon.net> wrote:
>> Deprecated certainly doesn't mean removed.
>> For a start, none of (DBI, ODBC, dbi, odbc) are standard Python-
>> supplied modules. Perhaps you are referring to the odbc (and dbi) from
>> the pywin32 package? Where did you get them from? If you can't
>> remember, try this:
>
> Thanks John. I mean the lower-case dbi and odbc modules from pywin32.
> Sorry for being vague. I assumed incorrectly they were part of the
> standard library because they came with pywin32.

pywin32 isn't part of the standard library, either - it just feels
like it if you're on Windows :-)

As you've already seen, the Python-Win32 list is probably of more use
to you: http://mail.python.org/mailman/listinfo/python-win32

Paul.


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 08:43:55 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 12:43:55 GMT
Subject: Fractions as result from divisions (was: Re: tough-to-explain
	Python)
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<c75ei6-e0i.ln1@satorlaser.homedns.org>
Message-ID: <00706f76$0$9711$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 11:24:28 +0200, Ulrich Eckhardt wrote:

> Bearophile wrote:
>> For example a novice wants to see 124 / 38 to return the 62/19 fraction
>> and not 3 or 3.263157894736842 :-)
> 
> Python has adopted the latter of the three for operator / and the the
> second one for operator //.

Up until a few years ago, / would return the integer division if both 
arguments where ints or longs, and // didn't even exist. Even in Python 
2.6, you still need to do

from __future__ import division 

to get the behaviour you describe.


> I wonder if it was considered to just return
> a fraction from that operation.

Because of his experience with ABC, Guido dislikes using fractions for 
standard arithmetic. He was resistant to even allowing the rational 
module be added to the standard library.

The problem with fractions is that, unless you're very careful, repeated 
arithmetic operations on numbers ends up giving you fractions like 

498655847957/569892397664

instead of the 7/8 you were expecting. Not only is that ugly, but it 
becomes slower and slower as the denominator and numerator become larger.

At least, that was Guido's experience.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 08:46:28 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 12:46:28 GMT
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2824.1247036789.8015.python-list@python.org>
Message-ID: <0070700f$0$9711$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 00:06:11 -0700, Dennis Lee Bieber wrote:

> 	Also, some applications may still have the file open, but Windows
> allows one to make copies of that file...


Not always though... some applications open files for exclusive read 
access.


-- 
Steven


From zephyrfalcon!NO_SPAM! at gmail.com  Wed Jul  8 08:51:30 2009
From: zephyrfalcon!NO_SPAM! at gmail.com (Hans Nowak)
Date: Wed, 08 Jul 2009 08:51:30 -0400
Subject: Fractions as result from divisions
In-Reply-To: <c75ei6-e0i.ln1@satorlaser.homedns.org>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<c75ei6-e0i.ln1@satorlaser.homedns.org>
Message-ID: <4A549652.9070408@gmail.com>

Ulrich Eckhardt wrote:
> Bearophile wrote:
>> For example a novice wants to see 124 / 38 to return the 62/19
>> fraction and not 3 or 3.263157894736842 :-)
> 
> Python has adopted the latter of the three for operator / and the the second
> one for operator //. I wonder if it was considered to just return a
> fraction from that operation.

http://python-history.blogspot.com/2009/03/problem-with-integer-division.html

"For example, in ABC, when you divided two integers, the result was an exact 
rational number representing the result. In Python however, integer division 
truncated the result to an integer.

In my experience, rational numbers didn't pan out as ABC's designers had hoped. 
A typical experience would be to write a simple program for some business 
application (say, doing one?s taxes), and find that it was running much slower 
than expected. After some debugging, the cause would be that internally the 
program was using rational numbers with thousands of digits of precision to 
represent values that would be truncated to two or three digits of precision 
upon printing. This could be easily fixed by starting an addition with an 
inexact zero, but this was often non-intuitive and hard to debug for beginners."

-- 
Hans Nowak (zephyrfalcon at gmail dot com)
http://4.flowsnake.org/


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 09:10:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 13:10:23 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
Message-ID: <007075aa$0$9711$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 12:23:50 +0000, kj wrote:

> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com>
> Simon Forman <sajmikins at gmail.com> writes:
> 
>>Frankly, I'm of the impression that it's a mistake not to start teaching
>>programming with /the bit/ and work your way up from there. I'm not
>>kidding. I wrote a (draft) article about this: "Computer Curriculum"
>>http://docs.google.com/View?id=dgwr777r_31g4572gp4
> 
>>I really think the only good way to teach computers and programming is
>>to start with a bit, and build up from there. "Ontology recapitulates
>>phylogeny"
> 
> 
> I happen to be very receptive to this point of view.
[...]
> There is this persistent idea "out there" that
> programming is a very accessible skill, like cooking or gardening,
> anyone can do it, and even profit from it, monetarily or otherwise,
> etc., and to some extent I am actively contributing to this perception
> by teaching this course to non-programmers (experimental biologists to
> be more precise), but maybe this idea is not entirely true...  

There is some evidence that 30-60% of people simply cannot learn to 
program, no matter how you teach them:

http://www.codinghorror.com/blog/archives/000635.html
http://www.cs.mdx.ac.uk/research/PhDArea/saeed/

I'm sympathetic to the idea, but not entirely convinced. Perhaps the 
problem isn't with the students, but with the teachers, and the 
languages: 

http://www.csse.monash.edu.au/~damian/papers/PDF/SevenDeadlySins.pdf

(My money is that it's a little of both.)


> Maybe, to
> get past the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest that
> real computer scientists learn about in their formal training...

The "No True Scotsman" fallacy.

There's nothing amateurish about building software applications that 
work, with well-designed interfaces and a minimum of bugs, even if you've 
never heard of Turing Machines.


-- 
Steven


From lucascarvalho at gmail.com  Wed Jul  8 09:11:35 2009
From: lucascarvalho at gmail.com (Lucas Carvalho)
Date: Wed, 08 Jul 2009 15:11:35 +0200
Subject: Remoting over SSH
In-Reply-To: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <4A549B07.2090402@gmail.com>

Hussein B wrote:
> Hey,
> I want to perform commands on a remote server over SSH.
> What do I need?
> Thanks.
>   
Hi,
 If you want to use the SSH2 protocol into a python code, you should
take a look at this module: paramiko [1].

[1] http://www.lag.net/paramiko/

Regards,
 Lucas.


From pruebauno at latinmail.com  Wed Jul  8 09:23:57 2009
From: pruebauno at latinmail.com (nn)
Date: Wed, 8 Jul 2009 06:23:57 -0700 (PDT)
Subject: library search path when compiling python
References: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>
	<mailman.2794.1246997166.8015.python-list@python.org>
Message-ID: <11e4f2f2-a32f-4671-a457-7cdd928d29fb@a7g2000yqk.googlegroups.com>

On Jul 7, 4:06?pm, Christian Heimes <li... at cheimes.de> wrote:
> nn wrote:
> > I am trying to compile python with ssl support but the libraries are
> > not in /usr/lib but in /opt/freeware/lib. How do I add that folder to
> > the default library search path?
>
> > It looks like configure --libdir=DIR might do the job but I don't want
> > to replace the default lib search path, just add an additional folder
> > to it.
>
> You didn't mention your OS. On Linux you can set the environment
> variable LD_RUN_PATH prior to compiling Python. The env var sets the
> rpath for the linker. See man ld(1) for details.
>
> Christian

Sorry I didn't realize that was OS specific. I am on AIX 5.3.


From no.email at please.post  Wed Jul  8 09:27:34 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 13:27:34 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
Message-ID: <h326s6$5sl$1@reader1.panix.com>

In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com> Simon Forman <sajmikins at gmail.com> writes:

>I'm not kidding. I wrote a (draft) article about this: "Computer
>Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4

Very cool.

kj


From aahz at pythoncraft.com  Wed Jul  8 09:40:34 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 06:40:34 -0700
Subject: Newbie needs help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>
	<mailman.2781.1246979580.8015.python-list@python.org>
Message-ID: <h327ki$8s6$1@panix3.panix.com>

In article <mailman.2781.1246979580.8015.python-list at python.org>,
Pablo Torres N. <tn.pablo at gmail.com> wrote:
>
>Give this one a try too: http://www.mikeash.com/getting_answers.html
>It doesn't talk down to you...as much :P

Nice!  I'll try remembering that one.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From p.f.moore at gmail.com  Wed Jul  8 09:47:48 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Wed, 8 Jul 2009 14:47:48 +0100
Subject: tough-to-explain Python
In-Reply-To: <h3234l$aod$1@reader1.panix.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
Message-ID: <79990c6b0907080647l22dce38epf03709b1119b2529@mail.gmail.com>

2009/7/8 kj <no.email at please.post>:
> There is this
> persistent idea "out there" that programming is a very accessible
> skill, like cooking or gardening, anyone can do it, and even profit
> from it, monetarily or otherwise, etc., and to some extent I am
> actively contributing to this perception by teaching this course
> to non-programmers (experimental biologists to be more precise),
> but maybe this idea is not entirely true... ?Maybe, to get past
> the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest
> that real computer scientists learn about in their formal training...

Look at it another way. Experimental biologists don't want to program,
they want to use computers to do experimental biology. It's a tool,
and they (quite reasonably) don't *care* about robustness,
portability, etc. Or even about programming, to be honest.

In the context of the original question, it's entirely reasonable (in
my view) to tell this audience "if the code does something weird you
don't understand, either ignore it and find another way or dig into
the manuals and experiment if you care". They'd very quickly find a =
a + b as a less confusing alternative to a += b. (As has been pointed
out earlier, to some extent a += b is quite an advanced construct -
after all, it's essentially an optimisation of a = a + b).

Biologists don't expect me to understand their discipline before I can
plant seeds in my garden, after all. (And when I do plant seeds, I
usually get far more surprising results than I could get from a += b
:-))

Paul.


From pruebauno at latinmail.com  Wed Jul  8 09:55:18 2009
From: pruebauno at latinmail.com (nn)
Date: Wed, 8 Jul 2009 06:55:18 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org> 
	<h30e3t$g56$2@reader1.panix.com>
Message-ID: <d0f7d666-d4f4-4b30-bf18-d2d1d5d805ff@y19g2000yqy.googlegroups.com>

On Jul 7, 5:18?pm, kj <no.em... at please.post> wrote:
> In <mailman.2796.1246997332.8015.python-l... at python.org> Chris Rebert <c... at rebertia.com> writes:
>
> >You might find the following helpful (partially):
> >http://effbot.org/zone/call-by-object.htm
>
> Extremely helpful. ?Thanks! ?(I learned more from it than someone
> who will teach the stuff would care to admit...)
>
> And it confirmed Paul Graham's often-made assertion that all of
> programming language design is still catching up to Lisp...
>
> kj

One possibility is to avoid teaching mutable datatypes at the
beginning (i.e. no lists,dicts and sets), then you would have
something more lispish. You would have to use tuples instead of lists
for everything. That avoids the gotchas of mutable types at the cost
of efficiency.

Python is not a purist language but rather walks a fine line between
high flexible abstractions and simple fast implementation.


From no.email at please.post  Wed Jul  8 10:04:35 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 14:04:35 +0000 (UTC)
Subject: The meaning of "=" (Was: tough-to-explain Python)
Message-ID: <h3291j$mfu$1@reader1.panix.com>

In <h30e3t$g56$2 at reader1.panix.com> kj <no.email at please.post> writes:

>I had not realized how *profoundly* different the meaning of the
>"=" in Python's

>  spam = ham

>is from the "=" in its

>  spam[3] = ham[3]


To clarify, this comes from my reading of Fredrik Lundh's pages
"Python Objects" (http://effbot.org/zone/python-objects.htm) and
"Call By Object" (http://effbot.org/zone/call-by-object.htm).
(Thanks to Chris Rebert for the pointer!)

In the first one of these pages, Lundh writes:

[START OF LENGTHY QUOTE]

  Assignment statements modify namespaces, not objects.

  In other words,

  name = 10

  means that you're adding the name 'name' to your local namespace,
  and making it refer to an integer object containing the value
  10.

  If the name is already present, the assignment replaces the
  original name:

  name = 10
  name = 20

  means that you're first adding the name 'name' to the local
  namespace, and making it refer to an integer object containing
  the value 10. You're then replacing the name, making it point to
  an integer object containing the value 20. The original '10'
  object isn't affected by this operation, and it doesn't care.

  In contrast, if you do:

  name = []
  name.append(1)

  you're first adding the name 'name' to the local namespace, making
  it refer to an empty list object. This modifies the namespace.
  You're then calling a method on that object, telling it to append
  an integer object to itself. This modifies the content of the
  list object, but it doesn't touch the namespace, and it doesn't
  touch the integer object.

  Things like name.attr and name[index] are just syntactic sugar
  for method calls. The first corresponds to __setattr__/__getattr__,
  the second to __setitem__/__getitem__ (depending on which side
  of the assignment they appear).

[END OF LENGTHY QUOTE]

Therefore, extending just a bit beyond Lundh's explanation, if we
did:

name = []
name.append(1)
name[0] = 3

...the second assignment would amount to a method call on the object
called 'name', an operation of a very different nature (according
to Lundh) from the first assignment, which is a modification of a
namespace.

In the second one of these pages, Lundh makes a very similar point
(third post from the bottom).

But note that Lundh appears to be contradicting himself somewhat
when he writes "Assignment statements modify namespaces, not
objects."  If by "assignment statements" he means ones consisting
of a left operand, a "=", and a right operand, then according to
the rest of what he writes on this subject, this assertion applies
only to *some* assignment statements, namely those of the form

  <identifier> = <expression>

and not to those like, for example,

  <identifier>[<expression>] = <expression>

or

  <identifier>.<identifier> = <expression>

The former are syntatic sugar for certain namespace modifications
that leave objects unchanged.  The latter are syntactic sugar for
certain object-modifying method calls that leave namespaces unchanged.

At least this is how I interpret what Lundh writes.

kj



From pdpinheiro at gmail.com  Wed Jul  8 10:06:09 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Wed, 8 Jul 2009 07:06:09 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
	<1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>
	<1f09e856-bd04-4d27-bf51-5d67953a7e13@y7g2000yqa.googlegroups.com> 
	<7xskh83r1v.fsf@ruckus.brouhaha.com>
Message-ID: <9b819fa8-92f0-4b73-866f-95097d0a5b03@c1g2000yqi.googlegroups.com>

On Jul 8, 2:24?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> pdpi <pdpinhe... at gmail.com> writes:
> > ? ? while abs(func(guess) - target) > epsilon:
> > ? ? ? ? guess = (lo + hi) / 2.
> > ? ? ? ? if sense * func(guess) > sense * target:
> > ? ? ? ? ? ? hi = guess
> > ? ? ? ? elif sense * func(guess) < sense * target:
> > ? ? ? ? ? ? lo = guess
> > ? ? ? ? elif lo == hi:
> > ? ? ? ? ? ? return None
> > ? ? return guess
>
> That is completely confusing. ?I get the, er, impression that "sense"
> is supposed to change during the loop, and it takes much head
> scratching to tell whether what you have there is right or not. ?Also,
> it calls func 3 times on each loop, which could be extremely slow.
> You don't know what func does, so eliminating 2/3 of the calls to it
> is not a micro-optimization--it could be a major time saving.
>
> Yet another version:
>
> ? ? def _binary_search(x0, x1, func, target, epsilon):
> ? ? ? ? y0,y1 = func(x0), func(x1)
> ? ? ? ? while abs(y1 - target) > epsilon:
> ? ? ? ? ? ? if x0 == x1 or cmp(y0,target) == cmp(y1,target):
> ? ? ? ? ? ? ? ? return None
> ? ? ? ? ? ? xn = (x0 + x1) / 2.
> ? ? ? ? ? ? yn = func(xn)
> ? ? ? ? ? ? if cmp(yn,target) == cmp(y0,target):
> ? ? ? ? ? ? ? ?x0,y0 = xn,yn
> ? ? ? ? ? ? else:
> ? ? ? ? ? ? ? ?x1,y1 = xn,yn
> ? ? ? ? return x1

micro-optimization was perhaps too harsh, but it is an optimization
that's not obvious for the newbie, and one best learnt from experience
rather than having it spoon fed. I'll restate: you should start with
the cleanest code possible and mangle it for performance. Then again,
that implicitly assumes that f(x) is more readable than y, which is
really a matter of taste...


From futurebase at gmx.at  Wed Jul  8 10:44:37 2009
From: futurebase at gmx.at (Daniel Austria)
Date: Wed, 8 Jul 2009 07:44:37 -0700 (PDT)
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
Message-ID: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>

Hi python - hackers,

just one question. How can i remove all 0 values in a list? Sure - i
can loop over it, but that s not a neat style.  list.remove() will
only remove the first occurence. Doing that while no exception is
raised is also uncool, right?

Some suggestions?


Best,
Dan


From paul at boddie.org.uk  Wed Jul  8 10:53:44 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Wed, 8 Jul 2009 07:53:44 -0700 (PDT)
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
Message-ID: <0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>

On 8 Jul, 16:04, kj <no.em... at please.post> wrote:
>
> ? <identifier> = <expression>
>
> and not to those like, for example,
>
> ? <identifier>[<expression>] = <expression>
>
> or
>
> ? <identifier>.<identifier> = <expression>
>
> The former are syntatic sugar for certain namespace modifications
> that leave objects unchanged. ?The latter are syntactic sugar for
> certain object-modifying method calls that leave namespaces unchanged.

Almost. The latter can modify namespaces - the objects themselves -
but through properties or dynamic attribute access, they may choose
not to modify such a namespace. Really, we can phrase assignment (=)
as follows:

<thing> = <expression> # make <thing> refer to the result of
<expression>

Here, <thing> has to provide something that can be made to refer to
something else, such as a name within a namespace - the first and last
of your cases - or an item or slice within a sequence - the special
second case which is actually handled differently from the other
cases.

Meanwhile, the <expression> will always provide an object to refer to,
never anything of the nature of <thing> referring to something else.
In other words, if you have this...

x[1] = y[2]

...then the <expression> which is y[2] will yield an object which is
then assigned to x[1]. The concept of y[2] is not assignable - it must
be fully evaluated and produce the object at location #2 in the
sequence for assignment.

I suppose you could say that the left-hand side <thing> is like a sign
on a signpost which always points to a real place, not another sign on
a signpost. You could stretch this analogy by treating sequences as
signposts holding many signs, each adjustable to point to something
different. Since signposts (not the individual signs) are located in
real places, they would naturally be acceptable as targets of
assignments: where the signs are allowed to point to. Indeed, this
would be a world of signposts with the occasional primitive value
mixed in to keep weary travellers interested. ;-)

Paul


From mabdelkader at gmail.com  Wed Jul  8 10:54:09 2009
From: mabdelkader at gmail.com (ma)
Date: Wed, 8 Jul 2009 10:54:09 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>

filter(lambda x: x, your_list)

On Wed, Jul 8, 2009 at 10:44 AM, Daniel Austria <futurebase at gmx.at> wrote:

> Hi python - hackers,
>
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.  list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
>
> Some suggestions?
>
>
> Best,
> Dan
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/f2433031/attachment.html>

From bruno.42.desthuilliers at websiteburo.invalid  Wed Jul  8 10:57:16 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Wed, 08 Jul 2009 16:57:16 +0200
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <4a54b3bf$0$405$426a74cc@news.free.fr>

Daniel Austria a ?crit :
> Hi python - hackers,
> 
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.  list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
> 
> Some suggestions?

the_list = [0, 0, 0, 1, 1, 1, 0]

# Simple solution
print [x for x in the_list if x != 0]

# if you want to mutate the list 'in place':
the_list[:] = [x for x in the_list if x != 0]
print the_list

HTH


From djames.suhanko at gmail.com  Wed Jul  8 10:59:38 2009
From: djames.suhanko at gmail.com (Djames Suhanko)
Date: Wed, 8 Jul 2009 11:59:38 -0300
Subject: Remoting over SSH
In-Reply-To: <007901c9ffc5$cef87780$0d00a8c0@Hendrik>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
	<007901c9ffc5$cef87780$0d00a8c0@Hendrik>
Message-ID: <fd9e6bba0907080759u344dd40bwb2cd11fbd4e6f95e@mail.gmail.com>

Hello!
 I wrote a litle program that send commands to many cluster nodes:

#!/usr/bin/env python
#By: Djames Suhanko

#servers list

sincroniza =["server1.domain","server2.domain", "server3.domain"]

import pexpect
import sys
from threading import Thread

#the user and pass can be in ini file.

#Test parameters list

try:
    if sys.argv[3]:
        pass
except:
    print  "Use: " + "script" + " <command> <user> <pass>"
    sys.exit()

#This function send  the command in argument
def executor(command,username,password,server):
    a = 'ssh ' + username + '@' + server
    foo = pexpect.spawn(a)
    foo.expect('.*ssword:')
    foo.sendline(password)
    foo.sendline('su')
    foo.expect('.*sword:')
    foo.sendline('root_password_here')
    foo.sendline(command + '&& exit')
    print "command to: " + server + "..........[OK]"
    foo.sendline('exit')
    foo.expect('.*osed.')
    foo.interact()

#make a list
tasks = []

#theading loop
for i in sincroniza:
    t = Thread(target=executor,args=(sys.argv[1],sys.argv[2],sys.argv[3],i))
    t.start()
    tasks.append(t)

#wait the end
for t in tasks:
    t.join()

it's all!
On Wed, Jul 8, 2009 at 9:15 AM, Hendrik van Rooyen<mail at microcorp.co.za> wrote:
> "Hussein B" <hubaghdadi at gmail.com> wrote:
>
>> Hey,
>> I want to perform commands on a remote server over SSH.
>> What do I need?
>> Thanks.
>
> Access privileges for the remote machine.
>
> - Hendrik
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Djames Suhanko
LinuxUser 158.760


From charles at declareSub.com  Wed Jul  8 11:02:16 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Wed, 8 Jul 2009 11:02:16 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
Message-ID: <A2C7533A-3BCF-493E-8FDA-900F82177757@declareSub.com>


On Jul 8, 2009, at 10:54 AM, ma wrote:

> filter(lambda x: x, your_list)
>
> On Wed, Jul 8, 2009 at 10:44 AM, Daniel Austria <futurebase at gmx.at>  
> wrote:
> Hi python - hackers,
>
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.  list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
>
> Some suggestions?
>


L = [0, 0, 0, 1, 1, 1, 0]
M = [x for x in L if x !=0]


Charles Yeomans
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/3e9ee60c/attachment.html>

From darcy at druid.net  Wed Jul  8 11:03:15 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Wed, 8 Jul 2009 11:03:15 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
Message-ID: <20090708110315.634de5d2.darcy@druid.net>

On Wed, 8 Jul 2009 10:54:09 -0400
ma <mabdelkader at gmail.com> wrote:
> filter(lambda x: x, your_list)

Or...

 [x for x in your_list if x]

I'm not sure which one is more efficient but I like the syntax of the
latter.  A smart person could probably figure it out even without
knowing Python syntax.  Clarity is trump.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From fridrik at pyth.net  Wed Jul  8 11:03:56 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Wed, 8 Jul 2009 15:03:56 +0000
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
Message-ID: <D0104C46-E4DE-473D-9B15-8A189945D6F0@pyth.net>


ma wrote:
> filter(lambda x: x, your_list)

Good call! Equivalent but more efficient:

  filter(None, your_list)

Regards,
Fri?rik M?r

From deets at nospam.web.de  Wed Jul  8 11:06:23 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 08 Jul 2009 17:06:23 +0200
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <7bjqndF22l519U1@mid.uni-berlin.de>

Daniel Austria wrote:

> Hi python - hackers,
> 
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.

Why not? If you need to potentially look at *all* elements of a list,
nothing but a loop will take you there.

OTOH, your proposed "remove until nothing is found"-thingy will become
quadratic in behavior, as remove also loops over the list - so if you have
list with say 10 ones followed by 10 zeros, you will loop ten times for 11
elements, which is in the order of (n/2)**2.

Diez


From nachogomez at gmail.com  Wed Jul  8 11:14:36 2009
From: nachogomez at gmail.com (=?UTF-8?B?UmHDumwgR8OzbWV6IEMu?=)
Date: Wed, 8 Jul 2009 10:44:36 -0430
Subject: Remoting over SSH
In-Reply-To: <fd9e6bba0907080759u344dd40bwb2cd11fbd4e6f95e@mail.gmail.com>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
	<007901c9ffc5$cef87780$0d00a8c0@Hendrik>
	<fd9e6bba0907080759u344dd40bwb2cd11fbd4e6f95e@mail.gmail.com>
Message-ID: <684b0a740907080814t4f4911e1u9b417aaaba76e44a@mail.gmail.com>

You also could use
TwistedConch<http://twistedmatrix.com/trac/wiki/TwistedConch>,
which is an implementation of the SSH2 protocol for Python. I've done
something with it, you can read my first questions on the TwistedConch list
here<http://twistedmatrix.com/pipermail/twisted-python/2007-October/016121.html>
.

Hope that helps...


-- 
Nacho
Linux Counter #156439
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/c2cde64f/attachment.html>

From no.email at please.post  Wed Jul  8 11:42:09 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 15:42:09 +0000 (UTC)
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
Message-ID: <h32eoh$ql8$1@reader1.panix.com>

In <0778f257-d36c-4e13-93ea-bf8d448c82e2 at b15g2000yqd.googlegroups.com> Paul Boddie <paul at boddie.org.uk> writes:

>On 8 Jul, 16:04, kj <no.em... at please.post> wrote:
>>
>> =A0 <identifier> =3D <expression>
>>
>> and not to those like, for example,
>>
>> =A0 <identifier>[<expression>] =3D <expression>
>>
>> or
>>
>> =A0 <identifier>.<identifier> =3D <expression>
>>
>> The former are syntatic sugar for certain namespace modifications
>> that leave objects unchanged. =A0The latter are syntactic sugar for
>> certain object-modifying method calls that leave namespaces unchanged.

>Almost. The latter can modify namespaces - the objects themselves -
>but through properties or dynamic attribute access, they may choose
>not to modify such a namespace. Really, we can phrase assignment (=3D)
>as follows:

><thing> =3D <expression> # make <thing> refer to the result of
><expression>

>Here, <thing> has to provide something that can be made to refer to
>something else, such as a name within a namespace - the first and last
>of your cases - or an item or slice within a sequence - the special
>second case which is actually handled differently from the other
>cases.

Thanks for this correction.

OK, so, scratching from my original post the case

<identifier>.<identifier> = <expression>

(as being a special case of <identifier> = <expression>), still,
to the extent that I understand your post, the "=" in

  x = 1

means something fundamentally different (in terms of Python's
underlying implementation) from the "=" in

  y[0] = 1

No?

>You could stretch this analogy by treating sequences as
>signposts holding many signs, each adjustable to point to something
>different.

Notionally, yes, I can see that, but there's no counterpart of this
analogy at the level of Python's implementation.  The "x" above is
a sign, as you put it, i.e. an entry in a namespace, but "y[0]"
is, in essence, a method call.

kj


From aahz at pythoncraft.com  Wed Jul  8 11:44:32 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 08:44:32 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
Message-ID: <h32et0$ika$1@panix3.panix.com>

In article <0778f257-d36c-4e13-93ea-bf8d448c82e2 at b15g2000yqd.googlegroups.com>,
Paul Boddie  <paul at boddie.org.uk> wrote:
>
>Almost. The latter can modify namespaces - the objects themselves -
>but through properties or dynamic attribute access, they may choose
>not to modify such a namespace. Really, we can phrase assignment (=)
>as follows:
>
><thing> = <expression> # make <thing> refer to the result of <expression>

Right, except s/thing/target/

http://docs.python.org/reference/simple_stmts.html#assignment-statements
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From matt0177 at gmail.com  Wed Jul  8 11:54:36 2009
From: matt0177 at gmail.com (Matthew Edmondson)
Date: Wed, 8 Jul 2009 08:54:36 -0700
Subject: Python Error from Apress book
In-Reply-To: <4A54687A.6010004@ieee.org>
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
	<4A5345B1.8050306@ieee.org>
	<op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
	<4A54687A.6010004@ieee.org>
Message-ID: <8e2cbd660907080854p65bad365p54ccdad4771786a6@mail.gmail.com>

I'm running XP SP3. The program now works great from either of the
directories, as long as include 'python' before it. As far as looking at the
error with stack trace, I really don't know enough yet to know how to do
that. I'm running the file from command line, because I'm not sure how to
run it referencing other files from idle. Lot to learn.....

Once again, thanks a ton for all of the help.

Matt

On Wed, Jul 8, 2009 at 2:35 AM, Dave Angel <davea at ieee.org> wrote:

>
>
> Gabriel Genellina wrote:
>
>> <div class="moz-text-flowed" style="font-family: -moz-fixed">En Tue, 07
>> Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
>>
>>> Gabriel Genellina wrote:
>>>
>>>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com>
>>>> escribi?:
>>>>
>>>
>>  When I try to run the command as outlined in
>>>>> the book "simple_markup2.py < test_input.txt > test_output.html i get
>>>>> the
>>>>> following error every time.
>>>>>
>>>>> IOError: [Errno 9] Bad file descriptor
>>>>>
>>>>
>>>> That's a Windows problem. When you execute the script as itself (either
>>>> as you do in the command line, or by double-clicking on it), it doesn't have
>>>> valid standard handles.
>>>> You have to invoke Python explicitely:
>>>>
>>>> python simple_markup2.py < test_input.txt > test_output.html
>>>>
>>>> (you may need to specify the full path to python.exe, or add the
>>>> directory where Python is installed to your system PATH).
>>>>
>>>>  I use stdout this way all the time, with no problem (python 2.6,
>>> Windows XP).  But as you point out, stdin redirection doesn't seem to work
>>> using the file associations.  I do get a different error though. When I look
>>> at sys.stdin, it shows an open file, with handle of zero, as expected.  But
>>> when I do a raw_input(), it gets:
>>>     EOFError: EOF when reading a line
>>>
>>
>> I think the error depends on the specific OS version/service pack. But at
>> least on XP this appears to fix it:
>>
>> http://support.microsoft.com/kb/321788/en-us
>>
>>  Thanks for the link.  Looking at that one, it indicates that Windows 2000
> fixed it in SP4, and XP fixed it in Sp1.  But I'm already running XP SP3, so
> I wonder if it's something new.
>
> Matt, what OS version are you running, and exactly what is happening when
> the error occurs?  (you should be able to figure that out from the stack
> trace)
>
>
> DaveA
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/231ac350/attachment.html>

From davea at ieee.org  Wed Jul  8 11:59:14 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 08 Jul 2009 11:59:14 -0400
Subject: tough-to-explain Python
In-Reply-To: <h3234l$aod$1@reader1.panix.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
Message-ID: <4A54C252.2090304@ieee.org>

kj wrote:
> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com> Simon Forman <sajmikins at gmail.com> writes:
>
>   
>> Frankly, I'm of the impression that it's a mistake not to start
>> teaching programming with /the bit/ and work your way up from there.
>> I'm not kidding. I wrote a (draft) article about this: "Computer
>> Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4
>>     
>
>   
>> I really think the only good way to teach computers and programming is
>> to start with a bit, and build up from there. "Ontology recapitulates
>> phylogeny"
>>     
>
>
> I happen to be very receptive to this point of view.  I had the
> benefit of that sort of training (one of the first computer courses
> I took started, believe it or not, with Turing machines, through
> coding in machine language, and compiler theory, and all the way
> up to dabbling with Unix!), and I suspect that the reason it is
> sometimes difficult for me to explain even relatively simple-looking
> things to others is that I have this background that I unconsciously,
> and incorrectly, take for granted in others...  There is this
> persistent idea "out there" that programming is a very accessible
> skill, like cooking or gardening, anyone can do it, and even profit
> from it, monetarily or otherwise, etc., and to some extent I am
> actively contributing to this perception by teaching this course
> to non-programmers (experimental biologists to be more precise),
> but maybe this idea is not entirely true...  Maybe, to get past
> the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest
> that real computer scientists learn about in their formal training...
>
> kj
>
>
>   
And I learned to program Analog Computers, along with APL, in an early 
course.  In my case assembly language came later, but by then we had 
covered the electronics behind transistors, and Karnough maps, logic 
diagrams, and so on.  By the time I graduated, I had five six-level 
languages and two assembly languages under my belt.

.DaveA


From aahz at pythoncraft.com  Wed Jul  8 11:59:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 08:59:19 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
	<h32eoh$ql8$1@reader1.panix.com>
Message-ID: <h32fon$264$1@panix3.panix.com>

In article <h32eoh$ql8$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>OK, so, scratching from my original post the case
>
><identifier>.<identifier> = <expression>
>
>(as being a special case of <identifier> = <expression>), still,
>to the extent that I understand your post, the "=" in
>
>  x = 1
>
>means something fundamentally different (in terms of Python's
>underlying implementation) from the "=" in
>
>  y[0] = 1
>
>No?

No.  ;-)  What's different is not the ``=`` but the construction of the
assignment target before ``=`` gets executed.  Consider also this:

x, y = y, x
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From xahlee at gmail.com  Wed Jul  8 12:19:23 2009
From: xahlee at gmail.com (Xah Lee)
Date: Wed, 8 Jul 2009 09:19:23 -0700 (PDT)
Subject: OT: unix to Windows technology
Message-ID: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>

Dear unixers & lispers,

i've been using Mac for the past 19 years, and been a professional sys
admin or web app developers on the unix platform, since 1998 (maily
Solaris, Apache, Perl, Java, SQL, PHP). In june, i bought a PC (not
for the first time though), and made a switch to Windows, for the
first time, in the sense as a developer instead of just a casual PC
user i've been.

In the past month, i've spend about 5 hours a day digging into MS
Windows tech, in particluar, read over 200 Wikipedia articles in
detail related to Windows technology. (192 of them linked)

Here's a write up of the whole story, my experiences, including some
tech introduction to MS Windows from a sys admin or programer point of
view.

? Switching from Mac/Unix To PC/Windows
  http://xahlee.org/mswin/switch_to_windows.html

Some slightly noteworthy subsections are:

? Removing HP/Compaq Software
  http://xahlee.org/mswin/hp_bundled_apps.html

? Installing Cygwin Tutorial
  http://xahlee.org/mswin/installing_cygwin.html

? Mac and Windows File Conversion
  http://xahlee.org/mswin/mac_windows_file_conv.html

? Unix And Windows File Permission Systems
  http://xahlee.org/mswin/file_perm_systems.html

? Introduction to Windows Scripting
  http://xahlee.org/mswin/windows_scripting.html

Some articles (not shown above) are still work in progress, such as
VBScript tutorial and PowerShell tutorial. Hoping to complete in the
coming months or years.

comment & feedback welcome, esp if you are a Windows expert and answer
some of my unanswered questions on the page.

  Xah
? http://xahlee.org/

?


From james at agentultra.com  Wed Jul  8 12:31:40 2009
From: james at agentultra.com (J Kenneth King)
Date: Wed, 08 Jul 2009 12:31:40 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
	<mailman.2844.1247065448.8015.python-list@python.org>
Message-ID: <858wizdtlf.fsf@agentultra.com>

Fri?rik M?r J?nsson <fridrik at pyth.net> writes:

> ma wrote:
>> filter(lambda x: x, your_list)
>
> Good call! Equivalent but more efficient:
>
>  filter(None, your_list)
>
> Regards,
> Fri?rik M?r

I was wondering when someone would mention filter()


From robert.kern at gmail.com  Wed Jul  8 12:38:33 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 08 Jul 2009 11:38:33 -0500
Subject: Does cProfile include IO wait time?
In-Reply-To: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>
References: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>
Message-ID: <h32i29$iut$1@ger.gmane.org>

On 2009-07-04 19:03, Matthew Wilson wrote:
> I have a command-line script that loads about 100 yaml files.  It takes
> 2 or 3 seconds.  I profiled my code and I'm using pstats to find what is
> the bottleneck.
>
> Here's the top 10 functions, sorted by internal time:
>
>      In [5]: _3.sort_stats('time').print_stats(10)
>      Sat Jul  4 13:25:40 2009    pitz_prof
>
>               756872 function calls (739759 primitive calls) in 8.621 CPU seconds
>
>         Ordered by: internal time
>         List reduced from 1700 to 10 due to restriction<10>
>
>         ncalls  tottime  percall  cumtime  percall filename:lineno(function)
>          15153    0.446    0.000    0.503    0.000 build/bdist.linux-i686/egg/yaml/reader.py:134(forward)
>          30530    0.424    0.000    0.842    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:142(need_more_tokens)
>          98037    0.423    0.000    0.423    0.000 build/bdist.linux-i686/egg/yaml/reader.py:122(peek)
>           1955    0.415    0.000    1.265    0.001 build/bdist.linux-i686/egg/yaml/scanner.py:1275(scan_plain)
>          69935    0.381    0.000    0.381    0.000 {isinstance}
>          18901    0.329    0.000    3.908    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:113(check_token)
>           5414    0.277    0.000    0.794    0.000 /home/matt/projects/pitz/pitz/__init__.py:34(f)
>          30935    0.258    0.000    0.364    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:276(stale_possible_simple_keys)
>          18945    0.192    0.000    0.314    0.000 /usr/local/lib/python2.6/uuid.py:180(__cmp__)
>           2368    0.172    0.000    1.345    0.001 build/bdist.linux-i686/egg/yaml/parser.py:268(parse_node)
>
> I expected to see a bunch of my IO file-reading code in there, but I don't.  So
> this makes me think that the profiler uses CPU time, not
> clock-on-the-wall time.

It should be basically wall-clock time on Linux. The timer function underneath 
is gettimeofday(2). Look in Modules/_lsprof.c of the Python sources for the 
function hpTimer().

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From no.email at please.post  Wed Jul  8 12:38:48 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 16:38:48 +0000 (UTC)
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
	<h32eoh$ql8$1@reader1.panix.com> <h32fon$264$1@panix3.panix.com>
Message-ID: <h32i2o$eop$1@reader1.panix.com>

In <h32fon$264$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>In article <h32eoh$ql8$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>
>>OK, so, scratching from my original post the case
>>
>><identifier>.<identifier> = <expression>
>>
>>(as being a special case of <identifier> = <expression>), still,
>>to the extent that I understand your post, the "=" in
>>
>>  x = 1
>>
>>means something fundamentally different (in terms of Python's
>>underlying implementation) from the "=" in
>>
>>  y[0] = 1
>>
>>No?

>No.  ;-)

No???  Just when I thought I finally understood all this!

>What's different is not the ``=`` but the construction of the
>assignment target before ``=`` gets executed.

Hmm.  OK, I went to the link you posted in your other message
(http://docs.python.org/reference/simple_stmts.html#assignment-statements)
and I find this (my emphasis):

    Assignment of an object to a single target is recursively defined as follows.

    * If the target is an identifier (name):

	  o If the name does not occur in a global statement in
	    the current code block: the name is bound to the object
                                    ^^^^^^^^^^^^^^^^^
	    in the current local namespace.

	  o Otherwise: the name is bound to the object in the
                       ^^^^^^^^^^^^^^^^^
	    current global namespace.

      The name is rebound if it was already bound. This may cause
      the reference count for the object previously bound to the
      name to reach zero, causing the object to be deallocated and
      its destructor (if it has one) to be called.

    * If the target is a target list enclosed in parentheses or in
      square brackets... (I'LL IGNORE THIS FOR NOW)

    * If the target is an attribute reference: The primary expression
      in the reference is evaluated. It should yield an object with
      assignable attributes; if this is not the case, TypeError is
      raised. That object is then asked to assign the assigned
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      object to the given attribute; if it cannot perform the
      ^^^^^^
      assignment, it raises an exception (usually but not necessarily
      AttributeError).

    * If the target is a subscription: The primary expression in
      the reference is evaluated. It should yield either a mutable
      sequence object (such as a list) or a mapping object (such
      as a dictionary). Next, the subscript expression is evaluated.

      If the primary is a mutable sequence object (such as a
      list),...  [CONDITIONS ON THE INDEX EXPRESSION OMITTED]...
      the sequence is asked to assign the assigned object to its
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      item with that index....

      If the primary is a mapping object (such as a dictionary),...
      [CONDITIONS ON THE SUBSCRIPT EXPRESSION OMITTED]... the
                                                          ^^^
      mapping is then asked to create a key/datum pair which maps
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      the subscript to the assigned object.
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    * If the target is a slicing: [INDEX STUFF OMITTED]... the
                                                           ^^^
      sequence object is asked to replace the slice with the items
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      of the assigned sequence...
      ^^^^^^^^^^^^^^^^^^^^^^^^

OK, I originally interpreted what Lundh wrote in his two articles
that the "binding" described at the very beginning (i.e. when the
target is an identifier), which I take to make an entry or modify
such an entry in a namespace, is a *categorically different*
operation from the remaining operations underlined above.

I interpreted Paul Boddie's correction in his response to me as
saying that the "assignment" mentioned for the case when the target
is an attribute reference is actually a special case of the
"assignment" to simple identifiers (i.e. it also means "binding").

But that still leaves all the other "assignments" (or the like)
underlined above.  I don't think that the full definitions of these
remaining cases are covered by the same rule, even though the rule
is described as "recursive."  I think that the writer has something
else in mind, and in particular, something *other* than binding,
but the author remains vague on exactly what this means.

Clearly, both Lundh and the documentation draw some distinction
between "binding" and some other forms of "assignment" (which remain
ill-defined throughout).  This distinction is what I was referring
to when I said that "=" means different things in different contexts.

kj


From fridrik at pyth.net  Wed Jul  8 12:44:47 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Wed, 8 Jul 2009 16:44:47 +0000
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <858wizdtlf.fsf@agentultra.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
	<mailman.2844.1247065448.8015.python-list@python.org>
	<858wizdtlf.fsf@agentultra.com>
Message-ID: <7D21C328-8320-4DF8-9E8B-08093441D270@pyth.net>

J Kenneth King wrote:
> I was wondering when someone would mention filter()

I was happy to see that too.

It's clean, faster than list comprehension and in terms of clarity  
it's only to be expected that the developer is familiar with, or at  
least willing to look up, the available built-in methods.

Regards,
Fri?rik M?r

From kentilton at gmail.com  Wed Jul  8 12:51:57 2009
From: kentilton at gmail.com (Kenneth Tilton)
Date: Wed, 08 Jul 2009 12:51:57 -0400
Subject: OT: unix to Windows technology
In-Reply-To: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
References: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
Message-ID: <4a54ceb0$0$5898$607ed4bc@cv.net>

Xah Lee wrote:
> Dear unixers & lispers,
> 
> i've been using Mac for the past 19 years, and been a professional sys
> admin or web app developers on the unix platform, since 1998 (maily
> Solaris, Apache, Perl, Java, SQL, PHP). In june, i bought a PC (not
> for the first time though), and made a switch to Windows, for the
> first time, in the sense as a developer instead of just a casual PC
> user i've been.
> 
> In the past month, i've spend about 5 hours a day digging into MS
> Windows tech, in particluar, read over 200 Wikipedia articles in
> detail related to Windows technology. (192 of them linked)
> 
> Here's a write up of the whole story, my experiences, including some
> tech introduction to MS Windows from a sys admin or programer point of
> view.
> 
> ? Switching from Mac/Unix To PC/Windows
>   http://xahlee.org/mswin/switch_to_windows.html
> 
> Some slightly noteworthy subsections are:
> 
> ? Removing HP/Compaq Software
>   http://xahlee.org/mswin/hp_bundled_apps.html
> 
> ? Installing Cygwin Tutorial
>   http://xahlee.org/mswin/installing_cygwin.html
> 
> ? Mac and Windows File Conversion
>   http://xahlee.org/mswin/mac_windows_file_conv.html
> 
> ? Unix And Windows File Permission Systems
>   http://xahlee.org/mswin/file_perm_systems.html
> 
> ? Introduction to Windows Scripting
>   http://xahlee.org/mswin/windows_scripting.html
> 
> Some articles (not shown above) are still work in progress, such as
> VBScript tutorial and PowerShell tutorial. Hoping to complete in the
> coming months or years.
> 
> comment & feedback welcome, esp if you are a Windows expert and answer
> some of my unanswered questions on the page.
> 
>   Xah
> ? http://xahlee.org/
> 
> ?

You just discovered PCs are cheaper?

The funny thing is that that is Microsoft's answer to the Apple Mac-PC 
ads, they show people shopping for computers and just comparing hardware 
and price as if this is some kind of breakthrough. But I understand: 
they have no answer to Windows being such a nightmare and the Mac being 
such a joy.

kt


From tjreedy at udel.edu  Wed Jul  8 12:57:31 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 08 Jul 2009 12:57:31 -0400
Subject: The meaning of "=" (Was: tough-to-explain Python)
In-Reply-To: <h3291j$mfu$1@reader1.panix.com>
References: <h3291j$mfu$1@reader1.panix.com>
Message-ID: <h32j5r$mn7$1@ger.gmane.org>

kj wrote:

> To clarify, this comes from my reading of Fredrik Lundh's pages
> "Python Objects" (http://effbot.org/zone/python-objects.htm) and
> "Call By Object" (http://effbot.org/zone/call-by-object.htm).
[snip]
> [END OF LENGTHY QUOTE]
> 
> Therefore, extending just a bit beyond Lundh's explanation, if we
> did:
> 
> name = []
> name.append(1)
> name[0] = 3
> 
> ...the second assignment would amount to a method call on the object
> called 'name', an operation of a very different nature (according
> to Lundh) from the first assignment, which is a modification of a
> namespace.

I disagree. Assignment creates an association. Modification of a 
namespace, when implemented, amounts to a method call on the concrete 
object, whether a Python object or not, that implements the abstraction 
of a namespace. At module scope,
   name = ob
is the same as
   globals()['name']=ob
Within a class statement, substitute '<class-dict>' for 'globals'
Within functions, CPython uses an internal array, so
   name = ob
becomes
   <locals_array>[name-number] = ob

Or, to put it another way, Python dicts and lists are, considered 
abstractly, associations also, just like namespaces. Dicts are more 
general than namespaces, sequences are 'number-spaces' instead of 
name-spaces.

Terry Jan Reedy



From nobody at nowhere.com  Wed Jul  8 13:03:35 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 08 Jul 2009 18:03:35 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
	<6xB4m.21104$vi5.8567@uutiset.elisa.fi>
	<pan.2009.07.07.22.37.43.422000@nowhere.com>
	<mailman.2818.1247033106.8015.python-list@python.org>
Message-ID: <pan.2009.07.08.17.03.35.547000@nowhere.com>

On Tue, 07 Jul 2009 22:49:22 -0700, Dennis Lee Bieber wrote:

> On Tue, 07 Jul 2009 23:37:43 +0100, Nobody <nobody at nowhere.com>
> declaimed the following in gmane.comp.python.general:
> 
>> AFAIK, the only real difference between "USB-1 conformant" and "USB-2
>> conformant" is that the latter actually passed a test of its ability to
>> say "no, I can't do high-speed", while the former didn't. The check for
>> high-speed capability was designed such that it shouldn't cause problems
>> for USB-1 devices, but individual USB-1 devices weren't actually tested
>> for this.
> 
> 	USB-1 or USB-1.1? As I recall the latter is capable of 11Mbps
> whereas the original USB spec was much lower... (of course, USB 2 at top
> is 480Mbps)

USB 1.0 supports 1.5Mbps (low-speed) and 12MBps (full-speed). Hosts and
hubs must support both, functions (devices) can use either. USB 1.1 was
a bug-fix release which solved some interoperability issues arising from
ambiguities in the USB 1.0 standard.



From lucas_junqueira at yahoo.com  Wed Jul  8 13:07:33 2009
From: lucas_junqueira at yahoo.com (Lucas Junqueira)
Date: Wed, 8 Jul 2009 10:07:33 -0700 (PDT)
Subject: windows command-line
Message-ID: <376017.28322.qm@web30601.mail.mud.yahoo.com>

Hi, I'd like to run a simple windows command-line program from within my python script and agt all the returt it generates. Is this possible? How can I do it?

Thank you!



      ____________________________________________________________________________________
Veja quais s?o os assuntos do momento no Yahoo! +Buscados
http://br.maisbuscados.yahoo.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/823cbd83/attachment.html>

From cameron.pulsford at gmail.com  Wed Jul  8 13:09:43 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Wed, 8 Jul 2009 13:09:43 -0400
Subject: Problem with list of dicts and copying
Message-ID: <5700df6b0907081009p5ec4167cqec36e915e0f6c4@mail.gmail.com>

Hello all, I'm redoing a sudoku solver of mine and I ran into an issue with
lists of dicts. Bear with me for a second before I get to the actual
problem... I'm representing the board as a dictionary, where the keys are
(x, y) positions, and the values are candidates. So my program goes along
picking numbers from the list of candidates and then propagating the
constraints. So it might place a 6, which would then remove 6 as a candidate
from that row column and grid. However, that might leave a spot with no
candidates, which means we placed a legal but not correct number. This is
where my problem arises. I keep a running list of the boards which is
updated every time I find a legal number that doesn't invalidate the boards.
I add onto this list by doing "boards.append(self.board.copy())". When I
place a legal but invalid number I do "self.board = boards[-1].copy()" to
return the board to the last known good state. And when I completely exhaust
the candidates for a spot and must backtrack to a different spot (instead of
simply trying a different candidate of the current spot) I do "self.board =
boards[-1].copy() and then del boards[-1]"
Basically my boards list should be copies of good boards, and when I need to
refresh the current board, I want to pull off a copy of the correct one.
Essentially (after watching the debugging output) it looks like this isn't
happening. I am always modifying the same board. The algo follows, and I can
post the rest of the code if necessary. So am I using the dict.copy() wrong?
Am I guessing I have a tricky problem with the "=" in "self.board =
boards[-1].copy()"

    def solve(self):
        previousValue = dict((blank, 0) for blank in self.blanks())
        self.fillInCandidates()
        continuing, boards, guesses = False, [self.board.copy()], 0
        while len(self.blanks()) > 0:
            if continuing == False:
                cp = self.mrv()
            continuing = False
            nl = self.nextLegal(cp, previousValue[cp])
            previousValue[cp] = nl
            if nl != 0:
                self.board[cp] = nl
                guesses += 1
                self.update(nl, cp[0], cp[1])
                if self.isNotLegal():
                    continuing = True
                    self.board = boards[-1].copy()
                else:
                    boards.append(self.board.copy())
            else:
                previousValue[cp] = 0
                self.board = boards[-1].copy()
                del boards[-1]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/18d7843a/attachment.html>

From nobody at nowhere.com  Wed Jul  8 13:19:16 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 08 Jul 2009 18:19:16 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
	<0ca855t29jklb0o0gi31ourfk3lstdiepf@4ax.com>
Message-ID: <pan.2009.07.08.17.19.16.640000@nowhere.com>

On Tue, 07 Jul 2009 22:11:12 -0700, Tim Roberts wrote:

>>The webcam is bound to do some encoding; most of them use USB "full speed"
>>(12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.
> 
> That's not true.  Most of the web cams made in the last 5 years or so run
> at high speed, 480 Mbps.  Full speed only gets you 1 fps at 640x480
> uncompressed, so it's really only useful for the most primitive video
> conference cams.

The very earliest models typically only did 320x200, while later USB-1
webcams used onboard compression to get a decent framerate.

For internet use, 12Mbps isn't that much of an obstacle; the internet
connection's upload speed is more likely to be the limiting factor. Faster
speeds are more useful for things like LAN-based CCTV systems.



From emile at fenx.com  Wed Jul  8 13:23:54 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 08 Jul 2009 10:23:54 -0700
Subject: windows command-line
In-Reply-To: <376017.28322.qm@web30601.mail.mud.yahoo.com>
References: <376017.28322.qm@web30601.mail.mud.yahoo.com>
Message-ID: <h32kne$s0l$1@ger.gmane.org>

On 7/8/2009 10:07 AM Lucas Junqueira said...
> Hi, I'd like to run a simple windows command-line program from within my 
> python script and agt all the returt it generates. Is this possible? How 
> can I do it?

Depending on python version, look into subprocess, commands or os.pipe 
and related.

Emile



From nobody at nowhere.com  Wed Jul  8 13:25:49 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 08 Jul 2009 18:25:49 +0100
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
Message-ID: <pan.2009.07.08.17.25.49.219000@nowhere.com>

On Tue, 07 Jul 2009 21:31:12 -0700, Rajat wrote:

>> > By the way most operating systems don't lock a file when it's opened for
>> > reading or writing or even executed.
>>
>> The general conclusion seems to be that mandatory locking is more trouble
>> than it's worth.
> 
> My OS is a windows XP sp3. All I'm trying to achieve is to close an
> application ( which could be a notepad, a wordpad or some other text
> editor) that have opened my file. Once the file is closed I can easily
> delete that file.
> 
> I guess, if file is opened by one of that application, the file must
> be locked and so is the reason I cannot delete the file.

Windows doesn't allow you to delete (or rename) open files. It's up to the
application as to whether it keeps the file open or closes it once it has
been read.

> Please suggest if this is fine.

If you can't delete the file, then you can't delete it. You shouldn't be
trying to kill off applications so that you can delete the file. Just do
what other Windows programs (including those which are part of Windows)
do: display a dialog telling the user to close the application then try
again.



From xahlee at gmail.com  Wed Jul  8 13:34:50 2009
From: xahlee at gmail.com (Xah Lee)
Date: Wed, 8 Jul 2009 10:34:50 -0700 (PDT)
Subject: OT: unix to Windows technology
References: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
	<4a54ceb0$0$5898$607ed4bc@cv.net>
Message-ID: <16430ee7-888e-42ef-9c84-14df4b78ee04@p36g2000prn.googlegroups.com>

Xah Lee wrote:
> ? Switching from Mac/Unix To PC/Windows
>  http://xahlee.org/mswin/switch_to_windows.html

Kenneth Tilton wrote:
> You just discovered PCs are cheaper?
>
> The funny thing is that that is Microsoft's answer to the Apple Mac-PC
> ads, they show people shopping for computers and just comparing hardware
> and price as if this is some kind of breakthrough. But I understand:
> they have no answer to Windows being such a nightmare and the Mac being
> such a joy.

well, i've been owning Macs for over the past 19 years. From a
dedicated fan thru-out the 1990s, to still fan in early of 2000s with
debut of OS X.

Mac prices in comparison to PC has gone up and downs. In the early
1990s for example, it is maybe 4 times more. Lowest is probably in the
mid 1990s, where 3rd party companies are licensed to producing clones,
and that happens to also be a period that Mac OS is the worst,
crashing few times per day, similar to Win 95 and 98. I think in the
early 2000s the price gap came closer, and since maybe 2005 it start
to increase again.

for someone like me, i've read all the pros and cons of Mac vs PC.
I've read, for instance, basically all MacWorld and MacUser mags in
the early 1990s until they become defunct. (and often MacWeek too) Not
to mention the huge amount of websites, especially in the late 1990s
where there are a number of high profile dedicated mac fan sites. I
also have often attended the yearly Mac World Expo, eagerly antipating
Steve Job's ?O, one more thing...?  etc... and etc and etc. As a
hyperbole, i've prob read more Mac vs PC argument from newsgroup users
combined. LOL

as to the price comparison... a better metric is value/price ratio. I
think, over the past 20 years, the value/price ratio of Mac compared
to PC, namely:

(MacValue/MacPrice)/(PC_value/PC_price)

is going down, starting with Windows NT 4, and going downhill quickly
with Windows XP, and Vista, .NET.

as far as SOFTWARE technology goes, Apple's falling lamer and lamer
from its 1990s mountain top of lisps and hypercards and desktop
publishing stuff. Microsoft Windows, starting from MS-DOS moronicity,
today, with its .NET, F#, PowerShell, is quite beyond Apple's
perpetual diddling with its prettification of OS X.

  Xah
? http://xahlee.org/

?


From paul.lafollette at gmail.com  Wed Jul  8 13:35:44 2009
From: paul.lafollette at gmail.com (Paul LaFollette)
Date: Wed, 8 Jul 2009 13:35:44 -0400
Subject: function local namespace question
Message-ID: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>

Kind people,

Using Python 3.1 under FreeBSD and WinXP.

I've been tearing my hair out trying to solve this myself, but I need
to ask for help.   I want (for obscure reasons) to be able to log
transactions in the namespace(s) of a script.  Specifically I would
like to log creation of identifiers, changes in the binding of
identifiers ("assignment") and lookups.  This turns out to be pretty
easy in the global and local namespaces... I simply subclass dict,
override the appropriate operations to include the logging operations
I want, and then exec the code using my dictionaries as the global and
local namespaces.  All  of this  works just dandy until I try to
extend it to functions.

I cannot figure out any way to get a hook into the local namespace of
a user defined function.  I have tried making a wrapper class that
grabs the function call and then uses exec to invoke
myfunction.__code__ with my own dictionaries.  This runs the (no
argument) function properly (losing the return value, but I can deal
with that) but never accesses the local logging dictionary that I
specify in the exec() call. Perhaps the local namespace of a function
is not a dict at all?

Anyway, is there any way (however clumsy) to do what I want to do?
Thank you for your help.
Paul

---------------------------
Paul LaFollette
CIS Department
Temple University
paul.lafollette(at)temple.edu
www.cis.temple.edu/~lafollet


From Lacrima.Maxim at gmail.com  Wed Jul  8 13:52:44 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Wed, 8 Jul 2009 10:52:44 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
Message-ID: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>

Hello!

I have just started using Emacs to write python scripts.
I installed python-mode.el

Then I just tried this code:

print 'hello world'

When I press C-c RET, new blank window is opened and emacs says:
(Shell command succeeded with no output)
So where is my 'hello world'?

When I do C-c C-c, it prints 'hello world' successfully.
Why in the first case I get no output?

Thanks in advance!

With regards, Max
(sorry if my English isn't very proper)


From sajmikins at gmail.com  Wed Jul  8 14:01:28 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Wed, 8 Jul 2009 11:01:28 -0700 (PDT)
Subject: ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <d9f7e0f1-3069-4d93-9839-1c7828a774b5@y17g2000yqn.googlegroups.com>

On Jul 8, 10:44?am, Daniel Austria <futureb... at gmx.at> wrote:
> Hi python - hackers,
>
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style. ?list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
>
> Some suggestions?
>
> Best,
> Dan

If you are doing something like this:

L = [0, 0, 0, 1, 1, 1, 0]
removeZeros(L)
number_of_ones = len(L)

you can just use sum() like so:

number_of_ones = sum(L)



HTH


From no.email at please.post  Wed Jul  8 14:10:08 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 18:10:08 +0000 (UTC)
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com> <m2r5wsb55n.fsf@cs.uu.nl>
Message-ID: <h32ne0$9l4$1@reader1.panix.com>

In <m2r5wsb55n.fsf at cs.uu.nl> Piet van Oostrum <piet at cs.uu.nl> writes:

>>>>>> kj <no.email at please.post> (kj) wrote:

>>kj> Does anyone know where I can buy the Python library reference in
>>kj> printed form?  (I'd rather not print the whole 1200+-page tome
>>kj> myself.)  I'm interested in both/either 2.6 and 3.0.

>Maybe you can have a copy printed at lulu.com.

Interesting idea...  Doesn't look like they offer such service.

>It would even be nicer if
>the PSF would offer them at lulu.

That would be great.

kj



From http  Wed Jul  8 14:43:19 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 11:43:19 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
Message-ID: <7xiqi3dni0.fsf@ruckus.brouhaha.com>

Bearophile <bearophileHUGS at lycos.com> writes:
> > ? ? print x, len(tuple(g))
> 
> Avoid that len(tuple(g)), use something like the following

print x, sum(1 for _ in g)


From http  Wed Jul  8 14:49:52 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 11:49:52 -0700
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <7xd48bdn73.fsf@ruckus.brouhaha.com>

Daniel Austria <futurebase at gmx.at> writes:
> just one question. How can i remove all 0 values in a list? 

I prefer:

   newlist = list(x for x in oldlist if x != 0)

to the square bracket list comprehension that a few people have
suggested.  This is because in python 2.x, the listcomp "leaks" its
index variable into the surrounding scope, but the generator
expression above doesn't.  Usually not a big deal, but an extra bit of
hygiene never(?) hurts.


From fetchinson at googlemail.com  Wed Jul  8 14:56:39 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Wed, 8 Jul 2009 11:56:39 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h31c14$k6m$4@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
	<mailman.2754.1246945937.8015.python-list@python.org>
	<4a531560$0$9355$426a74cc@news.free.fr>
	<fbe2e2100907070923n3caee67am2823d3b92209d6e4@mail.gmail.com>
	<h31c14$k6m$4@ger.gmane.org>
Message-ID: <fbe2e2100907081156t140246eemed6c68de6ead140d@mail.gmail.com>

>> But this academic discussion is honestly a little pointless. The OP
>> was referring to a expectation, coming from C, that is not fulfilled
>> in python. What's wrong with mentioning it somewhere for the sake of
>> helping C programmers?
>>
> 	And where does one stop? After all, my primary work language at the
> time I first encountered Python was FORTRAN77; and my home system at the
> time was an Amiga with ARexx... (granted, I did have a C compiler on it
> -- which I do not have on this WinXP machine)... And programming, even
> in C, on the Amiga still inflicted BCPL concepts upon one ("AmigaDOS",
> the "user" view, was a port of Tripos user view on top of the Amiga
> executive libraries).
>
> 	Do we mention how Python differs from F77, F90, Ada, Rexx, LISP,
> RPG, APL, Pascal, BASIC, and COBOL (I've done all except RPG since
> graduating high school).
>
> 	In my mind... Anyone whose only experience with programming language
> concepts is C/C++ deserves the shock of finding that other languages ARE
> DIFFERENT! Even if they never use other languages they should at least
> have been exposed to language design options and rationales...
>
> 	Okay, I don't know what current curricula consist of, but in the
> late 70s, a CS degree at my college required two sessions of FORTRAN,
> two of COBOL, Assembly (numerically, it followed advanced FORTRAN),
> database (followed COBOL)... and then diverged into Business Programming
> vs Systems Programming (Business required lots of accounting/statistics
> courses [stat-II was SPSS], Systems was operating system and language
> design). Electives included BASIC, Pascal, APL (The professor for the
> data structures course made the mistake of once allowing an assignment
> -- hashed head multiple-linked list -- to be done in any language he
> could read <G>; I did it in a BASIC that only supported 4 open files at
> a time... I think someone did it in SNOBOL)
>
> 	C wasn't available on the XEROX Sigma-7; I did have a first edition
> K&R. By graduation I'd also been exposed to the initial Ada
> reference/rational (a working compiler -- Ada/Ed -- didn't come out
> until after I'd graduated).


Okay, so where does one stop? I'd say C deserves special treatment as
opposed to all the other languages you mentioned because Guido himself
admits to influences from C (and ABC but I hope you won't assume that
ABC is a widely used language).

Maybe you didn't read these messages from me in this thread:

By the way, assignments in conditionals. Guido explicitly referred to
C when he forbade assignment in conditionals, citing common
typos/errors in C code such as if( x = 5 ){ .... } instead of if( x ==
5 ){ ..... }. So even he realized that warning people about different
usage in python and C is a good thing. Expectations from C work
sometimes, and sometimes they don't. In latter case a little warning
is useful.

And also,

Seriously, ask Guido about the influence of C vs. fortran (or cobol,
ada, pascal, etc). Somewhere you can find him quoted as saying that
python was originally intended to "bridge the gap between the shell
and C". I've never heard him talk about fortran (or cobol, ada,
pascal, etc).

So don't get me wrong, I'm sufficiently impressed by your knowledge of
various computer languages, I admit to only knowing C and basic and
some fortran (and of course python :)), but if Guido himself thinks
the influence of C on python is more important than the others, then
let's not doubt him.

And yes, I shamelessly admit to arguing based on a higher authority
and not based on merit, but in this case it's appropriate, I think :)

Cheers,
Daniel


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From backup95 at netcabo.pt  Wed Jul  8 15:32:36 2009
From: backup95 at netcabo.pt (=?ISO-8859-1?Q?Jo=E3o_Valverde?=)
Date: Wed, 08 Jul 2009 20:32:36 +0100
Subject: ISO library ref in printed form
In-Reply-To: <h2vcp9$66b$1@reader1.panix.com>
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <4A54F454.9060007@netcabo.pt>

kj wrote:
> Does anyone know where I can buy the Python library reference in
> printed form?  (I'd rather not print the whole 1200+-page tome
> myself.)  I'm interested in both/either 2.6 and 3.0.
>
> TIA!
>
> kj
>   
Why not download the documentation, take it to a local copy shop and 
have it printed and bound there?

http://docs.python.org/download.html
http://docs.python.org/3.1/download.html


From aahz at pythoncraft.com  Wed Jul  8 15:33:57 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 12:33:57 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
Message-ID: <h32sb5$eoq$1@panix3.panix.com>

In article <050094ea-faf4-4e03-875d-9c2c63090a89 at y17g2000yqn.googlegroups.com>,
Bearophile  <bearophileHUGS at lycos.com> wrote:
>Vilya Harvey:
>>
>> from itertools import groupby
>> for x, g in groupby([fields[1] for fields in data]):
>> =A0 =A0 print x, len(tuple(g))
>
>Avoid that len(tuple(g)), use something like the following, it's lazy
>and saves some memory.

The question is whether it saves time, have you tested it?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From piet at cs.uu.nl  Wed Jul  8 15:54:23 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 21:54:23 +0200
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
Message-ID: <m21vorar2o.fsf@cs.uu.nl>

>>>>> Lacrima <Lacrima.Maxim at gmail.com> (L) wrote:

>L> Hello!
>L> I have just started using Emacs to write python scripts.
>L> I installed python-mode.el

>L> Then I just tried this code:

>L> print 'hello world'

>L> When I press C-c RET, new blank window is opened and emacs says:
>L> (Shell command succeeded with no output)
>L> So where is my 'hello world'?

>L> When I do C-c C-c, it prints 'hello world' successfully.
>L> Why in the first case I get no output?

Can you check in the buffer where you have the python code what command
C-c RET is bound to?
With C-h k C-c RET

Shell command succeeded with no output suggests that is has a different
binding than the standard one in python-mode.

Did you happen to name your file 'test' or 'test.py?

C-c RET does an import and 'import test' imports a standard module test.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul  8 15:56:01 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 21:56:01 +0200
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com> <m2r5wsb55n.fsf@cs.uu.nl>
	<h32ne0$9l4$1@reader1.panix.com>
Message-ID: <m2ws6j9cfi.fsf@cs.uu.nl>

>>>>> kj <no.email at please.post> (k) wrote:

>k> In <m2r5wsb55n.fsf at cs.uu.nl> Piet van Oostrum <piet at cs.uu.nl> writes:
>>>>>>>> kj <no.email at please.post> (kj) wrote:

>kj> Does anyone know where I can buy the Python library reference in
>kj> printed form?  (I'd rather not print the whole 1200+-page tome
>kj> myself.)  I'm interested in both/either 2.6 and 3.0.

>>> Maybe you can have a copy printed at lulu.com.

>k> Interesting idea...  Doesn't look like they offer such service.

You can upload your own PDF file and have them print a single copy. You
would have to split the file yourself in manageble pieces (< 600
something pages)

>>> It would even be nicer if
>>> the PSF would offer them at lulu.

>k> That would be great.

>k> kj


-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From milesck at umich.edu  Wed Jul  8 16:50:44 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 8 Jul 2009 16:50:44 -0400
Subject: function local namespace question
In-Reply-To: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
References: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
Message-ID: <BFCC62EC-32DF-4E0E-B9E9-DD99D2262F1C@umich.edu>

On Jul 8, 2009, at 1:35 PM, Paul LaFollette wrote:

> I cannot figure out any way to get a hook into the local namespace of
> a user defined function.  I have tried making a wrapper class that
> grabs the function call and then uses exec to invoke
> myfunction.__code__ with my own dictionaries.  This runs the (no
> argument) function properly (losing the return value, but I can deal
> with that) but never accesses the local logging dictionary that I
> specify in the exec() call. Perhaps the local namespace of a function
> is not a dict at all?

Right.  Within functions, local variable name accesses and assignments  
are compiled into bytecode instructions (LOAD_FAST, STORE_FAST) that  
manipulate pointers to objects by indexing directly into a C array in  
the frame.  The "locals" dictionary of a frame is generated on-demand  
from that array when accessed.  There is no way that I'm aware of to  
directly hook into function namespace access and manipulation.

-Miles



From http  Wed Jul  8 17:45:53 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 14:45:53 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>
Message-ID: <7xbpnuzw4u.fsf@ruckus.brouhaha.com>

aahz at pythoncraft.com (Aahz) writes:
> >Avoid that len(tuple(g)), use something like the following, it's lazy
> >and saves some memory.
> The question is whether it saves time, have you tested it?

len(tuple(xrange(100000000))) ... hmm.


From david.bramer at googlemail.com  Wed Jul  8 18:06:22 2009
From: david.bramer at googlemail.com (David)
Date: Wed, 8 Jul 2009 15:06:22 -0700 (PDT)
Subject: regex help
Message-ID: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>

Hi

I have a few regexs I need to do, but im struggling to come up with a
nice way of doing them, and more than anything am here to learn some
tricks and some neat code rather than getting an answer - although
thats obviously what i would like to get to.

Problem 1 -

<span class="chg"
                id="ref_678774_cp">(25.47%)</span><br>

I want to extract 25.47 from here - so far I've tried -

xPer = re.search('<span class="chg" id="ref_"'+str(xID.group(1))+'"_cp
\">(.*?)%', content)

and

xPer = re.search('<span class=\"chg\" id=\"ref_"+str(xID.group(1))+"_cp
\">\((\d*)%\)</span><br>', content)

neither of these seem to do what I want - am I not doing this
correctly? (obviously!)

Problem 2 -

<td>&nbsp;</td>

<td width="1%" class=key>Open:
</td>
<td width="1%" class=val>5.50
</td>
<td>&nbsp;</td>
<td width="1%" class=key>Mkt Cap:
</td>
<td width="1%" class=val>6.92M
</td>
<td>&nbsp;</td>
<td width="1%" class=key>P/E:
</td>
<td width="1%" class=val>21.99
</td>


I want to extract the open, mkt cap and P/E values - but apart from
doing loads of indivdual REs which I think would look messy, I can't
think of a better and neater looking way. Any ideas?

Cheers

David



From aahz at pythoncraft.com  Wed Jul  8 18:22:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 15:22:19 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>
	<7xbpnuzw4u.fsf@ruckus.brouhaha.com>
Message-ID: <h3366r$du7$1@panix3.panix.com>

In article <7xbpnuzw4u.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>aahz at pythoncraft.com (Aahz) writes:
>>Paul Rubin deleted an attribution:
>>>
>>>Avoid that len(tuple(g)), use something like the following, it's lazy
>>>and saves some memory.
>>
>> The question is whether it saves time, have you tested it?
>
>len(tuple(xrange(100000000))) ... hmm.

When dealing with small N, O() can get easily swamped by the constant
factors.  How often do you deal with more than a hundred fields?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From digitig at gmail.com  Wed Jul  8 18:25:21 2009
From: digitig at gmail.com (Tim Rowe)
Date: Wed, 8 Jul 2009 23:25:21 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006e7ce0$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <aee48b3c0907081525u72320104hd88af95036e545f1@mail.gmail.com>

2009/7/7 Steven D'Aprano <steve at remove-this-cybersource.com.au>:

> Maybe the reason for "so much buggy software" is that people
> inappropriately use assert, thus changing the behaviour of code depending
> on whether it is run with the -O flag or not.

I've done my share of code review and process audits, and assertions
seem *far* to rare for that distinction.

> I don't know what "hostility" you're seeing. The only hostility I'm
> seeing is from the OP, which is bizarre considering that he asked for
> advice and we gave it. What I see is a bunch of people concerned that the
> OP is teaching novices a bad habit, namely, using assert for error
> checking. He claims -- angrily and over and over again -- that in his
> code, the assertions should never fail. Great. Good for him for knowing
> when to use assert. But are the novices going to learn that lesson, or
> will they simply learn "use assert for error checking"?

They are rather more likely to learn if they are taught, aren't they?
Or do you think it's better to keep them in the dark? "There are these
things called assertions -- work them out for yourselves".

I am convinced that the time to teach programmers to consider under
what circumstances a routine can be called and who is responsible for
ensuring that those conditions are met is as soon as they hit the
concept of calling routines. And assertions provide an excellent way
of doing that, fostering good habits for the rest of their careers.
Any hostility from the OP seems to be a response to the persistent
refusal to accept his assurances that he is not using the assertions
for run-time error checking, nor teaching the students to do that,
-- 
Tim Rowe


From http  Wed Jul  8 18:28:17 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 15:28:17 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>
	<7xbpnuzw4u.fsf@ruckus.brouhaha.com>
	<h3366r$du7$1@panix3.panix.com>
Message-ID: <7xvdm2n726.fsf@ruckus.brouhaha.com>

aahz at pythoncraft.com (Aahz) writes:
> When dealing with small N, O() can get easily swamped by the constant
> factors.  How often do you deal with more than a hundred fields?

The number of fields in the OP's post was not stated.  Expecting it to
be less than 100 seems like an ill-advised presumption.  If N is
unknown, speed-tuning the case where N is small at the expense of
consuming monstrous amounts of memory when N is large sounds 
somewhere between a premature optimization and a nasty bug.



From clp2 at rebertia.com  Wed Jul  8 18:37:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 8 Jul 2009 15:37:48 -0700
Subject: regex help
In-Reply-To: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
Message-ID: <50697b2c0907081537v44c45510kf8e9f143e2213a0@mail.gmail.com>

On Wed, Jul 8, 2009 at 3:06 PM, David<david.bramer at googlemail.com> wrote:
> Hi
>
> I have a few regexs I need to do, but im struggling to come up with a
> nice way of doing them, and more than anything am here to learn some
> tricks and some neat code rather than getting an answer - although
> thats obviously what i would like to get to.
>
> Problem 1 -
>
> <span class="chg"
> ? ? ? ? ? ? ? ?id="ref_678774_cp">(25.47%)</span><br>
>
> I want to extract 25.47 from here - so far I've tried -
>
> xPer = re.search('<span class="chg" id="ref_"'+str(xID.group(1))+'"_cp
> \">(.*?)%', content)
>
> and
>
> xPer = re.search('<span class=\"chg\" id=\"ref_"+str(xID.group(1))+"_cp
> \">\((\d*)%\)</span><br>', content)
>
> neither of these seem to do what I want - am I not doing this
> correctly? (obviously!)
>
> Problem 2 -
>
> <td>&nbsp;</td>
>
> <td width="1%" class=key>Open:
> </td>
> <td width="1%" class=val>5.50
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>Mkt Cap:
> </td>
> <td width="1%" class=val>6.92M
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>P/E:
> </td>
> <td width="1%" class=val>21.99
> </td>
>
>
> I want to extract the open, mkt cap and P/E values - but apart from
> doing loads of indivdual REs which I think would look messy, I can't
> think of a better and neater looking way. Any ideas?

Use an actual HTML parser? Like BeautifulSoup
(http://www.crummy.com/software/BeautifulSoup/), for instance.

I will never understand why so many people try to parse/scrape
HTML/XML with regexes...

Cheers,
Chris
-- 
http://blog.rebertia.com


From usernet at ilthio.net  Wed Jul  8 18:43:41 2009
From: usernet at ilthio.net (Tim Harig)
Date: Wed, 08 Jul 2009 22:43:41 GMT
Subject: regex help
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
	<mailman.2860.1247092671.8015.python-list@python.org>
Message-ID: <xi95m.3641$vO4.3538@flpi145.ffdc.sbc.com>

On 2009-07-08, Chris Rebert <clp2 at rebertia.com> wrote:
> On Wed, Jul 8, 2009 at 3:06 PM, David<david.bramer at googlemail.com> wrote:
>> I want to extract the open, mkt cap and P/E values - but apart from
>> doing loads of indivdual REs which I think would look messy, I can't
>> think of a better and neater looking way. Any ideas?

You are downloading market data?  Yahoo offers its stats in CSV format that
is easier to parse without a dedicated parser.

> Use an actual HTML parser? Like BeautifulSoup
> (http://www.crummy.com/software/BeautifulSoup/), for instance.

I agree with your sentiment exactly.  If the regex he is trying to get is
difficult enough that he has to ask; then, yes, he should be using a
parser.

> I will never understand why so many people try to parse/scrape
> HTML/XML with regexes...

Why?  Because some times it is good enough to get the job done easily.


From thebrasse at gmail.com  Wed Jul  8 18:43:59 2009
From: thebrasse at gmail.com (=?ISO-8859-1?Q?Mattias_Br=E4ndstr=F6m?=)
Date: Wed, 8 Jul 2009 15:43:59 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<MeqdnTn37r9N-s_XnZ2dnUVZ_jCdnZ2d@pdx.net>
Message-ID: <48bcf21c-4c40-4d49-9966-e0cedfdf206e@d4g2000yqa.googlegroups.com>

On Jul 6, 11:15?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> brasse wrote:
> > I have been thinking about how write exception safe constructors in
> > Python. By exception safe I mean a constructor that does not leak
> > resources when an exception is raised within it.
>
> ...
> ?> As you can see this is less than straight forward. Is there some kind
> ?> of best practice that I'm not aware of?
>
> Not so tough. ?Something like this tweaked version of your example:
>
> class Foo(object):
> ? ? ?def __init__(self, name, fail=False):
> ? ? ? ? ?self.name = name
> ? ? ? ? ?if not fail:
> ? ? ? ? ? ? ?print '%s.__init__(%s)' % (type(self).__name__, name)
> ? ? ? ? ?else:
> ? ? ? ? ? ? ?print '%s.__init__(%s), FAIL' % (type(self).__name__, name)
> ? ? ? ? ? ? ?raise ValueError('Asked to fail: %r' % fail)
>
> ? ? ?def close(self):
> ? ? ? ? ?print '%s.close(%s)' % (type(self).__name__, self.name)
>
> class Bar(object):
> ? ? ?def __init__(self):
> ? ? ? ? ?unwind = []
> ? ? ? ? ?try:
> ? ? ? ? ? ? ?self.a = Foo('a')
> ? ? ? ? ? ? ?unwind.append(a)
> ? ? ? ? ? ? ?self.b = Foo('b', fail=True)
> ? ? ? ? ? ? ?unwind.append(b)
> ? ? ? ? ? ? ?...
> ? ? ? ? ?except Exception, why:
> ? ? ? ? ? ? ?while unwind):
> ? ? ? ? ? ? ? ? ?unwind.pop().close()
> ? ? ? ? ? ? ?raise
>
> bar = Bar()
>

OK. That's another way. I have been thinking about this some more and
right now I am experimenting with a decorator that could help me do
these kinds of things. This is what I have right now:

import functools

class Foo(object):
    def __init__(self, name, fail=False):
        self.name = name
        self.closed = False
        if not fail:
            print '%s.__init__(%s)' % (self.__class__.__name__,
self.name)
        else:
            print '%s.__init__(%s), FAIL' % (self.__class__.__name__,
                                             self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)

def safe(f):
    @functools.wraps(f)
    def wrapper(self, *args, **kwargs):
        variables = []
        def recorder(self, name, value):
            if name != '__class__':
                variables.append(name)
            object.__setattr__(self, name, value)

        class Customized(object): pass
        setattr(Customized, '__setattr__', recorder)
        old_class = self.__class__
        self.__class__ = Customized

        try:
            f(self, *args, **kwargs)
            self.__class__ = old_class
        except:
            # clean up objects created in __init__ (i.e. the call to f
())
            for name in reversed(variables):
                o = getattr(self, name)
                if hasattr(o, 'close'):
                    o.close()
            raise
    return wrapper

class Bar(object):
    @safe
    def __init__(self):
        self.a = Foo('a')
        self.b = Foo('b')
        self.c = Foo('c', fail=True)

bar = Bar()

The safe decorator will record all attributes created on self. If an
exception is raised during the execution of the decorated constructor
it will call close on all the recorded objects. I realize that this
decorator still needs a lot of work before it is usable, but I think
it illustrates the concept. It might even be possible for the
decorator to create a close/cleanup method dynamically.

To have a decorator like this that actually worked would be great
since it would remove the need to write error prone cleanup code. Any
thoughts?

:.:: mattias

> --Scott David Daniels
> Scott.Dani... at Acm.Org



From fabiofz at gmail.com  Wed Jul  8 19:01:40 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Wed, 8 Jul 2009 20:01:40 -0300
Subject: Pydev 1.4.7 Released
Message-ID: <cfb578b20907081601o7e6acb7dq61672f3df43065be@mail.gmail.com>

Hi All,

Pydev and Pydev Extensions 1.4.7 have been released

Details on Pydev Extensions: http://www.fabioz.com/pydev
Details on Pydev: http://pydev.sf.net
Details on its development: http://pydev.blogspot.com

Release Highlights in Pydev Extensions:
-----------------------------------------------------------------

* The interactive console can be used on the remote debugger
* Remote debugger properly redirects contents from the server on multiple runs.
* Providing context-independent completions when other completions are
not available (until now, it only gave those completions for method
parameters)
* The number of chars required to show the context-insensitive
completion can now be customized.
* Fixed problem with Eclipse 3.5: "Invalid Thread Access" when trying
to rename a class


Release Highlights in Pydev:
----------------------------------------------

* Iron Python support
* Fixed issue when configuring interpreter on Eclipse 3.3 and 3.2 (was
using API only available in 3.4)
* Google App Engine
      o Popup menus for google app engine are now working with eclipse 3.2
      o Fixed issues when google app engine project has spaces in path
* Launching
      o Ctrl+F9 can be used to run as unit-test and select which tests
will be run
      o F9 will now run the current editor based on the project type
      o Changed run icons
      o Run configurations can be created for the project
      o Run as unit-test can have --filter and --tests as a parameter
set in the run configuration
* Shift left can now shift even when there are less chars than the
required indent string
* Top-level modules on .egg files are now properly recognized
* Auto-config fixed
* Fixed problem when .pydevproject was not a parseable xml file (the
pydev package explorer wouldn't work because of that)
* When a new interpreter is created, it's properly selected in the tree
* Code-completion better heuristic when analyzing function return
that's called on self.
* Code-completion in the interactive console now handles import
sections correctly
* Code formatter: Spaces after square and curly braces are no longer
changed when an unary operator is found afterwards
* Fixed problem when recognizing encodings (regexp was not correct)



What is PyDev?
---------------------------

PyDev is a plugin that enables users to use Eclipse for Python, Jython
and Iron Python development -- making Eclipse a first class Python IDE
-- It comes with many goodies such as code completion, syntax
highlighting, syntax analysis, refactor, debug and many others.


Cheers,

-- 
Fabio Zadrozny
------------------------------------------------------
Software Developer

Aptana
http://aptana.com/python

Pydev Extensions
http://www.fabioz.com/pydev

Pydev - Python Development Environment for Eclipse
http://pydev.sf.net
http://pydev.blogspot.com


From helvinlui at gmail.com  Wed Jul  8 19:10:37 2009
From: helvinlui at gmail.com (Helvin)
Date: Wed, 8 Jul 2009 16:10:37 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org>
Message-ID: <60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>

On Jul 8, 9:23?pm, Phil Thompson <p... at riverbankcomputing.com> wrote:
> On Wed, 08 Jul 2009 11:11:51 +0200, "Diez B. Roggisch"
> <de... at nospam.web.de>
> wrote:
>
>
>
>
>
> > Helvin wrote:
>
> >> Hi experts!
>
> >> I'm developing a GUI for a software using PyQT, and need 3D
> >> visualization. Should I use PyOpenGL or VTK?
> >> I understand that the PyQt package comes with a opengl module. What
> >> else would I need? I think I need to download opengl. but how? where?
> >> I have VTK and pyVTK installed, but I don't know how to use it in my
> >> code, as when I run it, an error says it can't find the vtk module.
>
> > VTK won't mix with Qt. And I don't think you need to download opengl - it
> > either comes with your system (or gfx-drivers), or not. I'm not sure if
> Qt
> > actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
> > PyOpenGL I guess.
>
> VTK has explicit support for both Qt (ie. via C++) and PyQt.
>
> Phil

Thanks for the fast replies! I will look into how to use VTK now.
Where would I find VTK's explicit support for PyQt?

Because I have installed VTK (using its installer) and pyVTK (using
its setup.py file), but how do I actually use it in my code? According
to: http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521455.html,
I have tried 'import vtk', but python can't find the vtk module.

Thanks a million!
Helvin


From psimon at sonic.net  Wed Jul  8 19:18:02 2009
From: psimon at sonic.net (Paul Simon)
Date: Wed, 8 Jul 2009 16:18:02 -0700
Subject: tkinter problem
Message-ID: <4a55292f$0$95538$742ec2ed@news.sonic.net>

I have the "tkinter" problem and need some assistance to straighten it out.
>From the web page "http://wiki.python.org/moin/TkInter" I tested as in "step
1" and cannot import "_tkinter." I do not have that file on my computer, but
do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
This  python stuff is great, but the documentation frequently
feels like it is just a bit out of my grasp. I realize that all of this is
free but I understand the instructions on the web page to repair only to the
point of confusion. I'm not an expert. How do I modify my python
configuration? Is there a file that needs to be edited? Which setup.py file
do I use? Make? or python setup.py build and python setup.py install?
Thanks. I appreciate your help.
Paul Simon 




From rhodri at wildebst.demon.co.uk  Wed Jul  8 19:20:59 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 09 Jul 2009 00:20:59 +0100
Subject: regex help
In-Reply-To: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
Message-ID: <op.uwru49xna8ncjz@gnudebst>

On Wed, 08 Jul 2009 23:06:22 +0100, David <david.bramer at googlemail.com>  
wrote:

> Hi
>
> I have a few regexs I need to do, but im struggling to come up with a
> nice way of doing them, and more than anything am here to learn some
> tricks and some neat code rather than getting an answer - although
> thats obviously what i would like to get to.
>
> Problem 1 -
>
> <span class="chg"
>                 id="ref_678774_cp">(25.47%)</span><br>
>
> I want to extract 25.47 from here - so far I've tried -
>
> xPer = re.search('<span class="chg" id="ref_"'+str(xID.group(1))+'"_cp
> \">(.*?)%', content)

Supposing that str(xID.group(1)) == "678774", let's see how that string
concatenation turns out:

<span class="chg" id="ref_"678774"_cp">(.*?)%

The obvious problems here are the spurious double quotes, the spurious
(but harmless) escaping of a double quote, and the lack of (escaped)
backslash and (escaped) open parenthesis.  The latter you can always
strip off later, but the first sink the match rather thoroughly.

>
> and
>
> xPer = re.search('<span class=\"chg\" id=\"ref_"+str(xID.group(1))+"_cp
> \">\((\d*)%\)</span><br>', content)

With only two single quotes present, the biggest problem should be obvious.

Unfortunately if you just fix the obvious in either of the two regular
expressions, you're setting yourself up for a fall later on.  As The Fine
Manual says right at the top of the page on the re module
(http://docs.python.org/library/re.html), you want to be using raw string
literals when you're dealing with regular expressions, because you want
the backslashes getting through without being interpreted specially by
Python's own parser.  As it happens you get away with it in this case,
since neither '\d' nor '\(' have a special meaning to Python, so aren't
changed, and '\"' is interpreted as '"', which happens to be the right
thing anyway.


> Problem 2 -
>
> <td>&nbsp;</td>
>
> <td width="1%" class=key>Open:
> </td>
> <td width="1%" class=val>5.50
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>Mkt Cap:
> </td>
> <td width="1%" class=val>6.92M
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>P/E:
> </td>
> <td width="1%" class=val>21.99
> </td>
>
>
> I want to extract the open, mkt cap and P/E values - but apart from
> doing loads of indivdual REs which I think would look messy, I can't
> think of a better and neater looking way. Any ideas?

What you're trying to do is inherently messy.  You might want to use
something like BeautifulSoup to hide the mess, but never having had
cause to use it myself I couldn't say for sure.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From clp2 at rebertia.com  Wed Jul  8 19:22:14 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 8 Jul 2009 16:22:14 -0700
Subject: tkinter problem
In-Reply-To: <4a55292f$0$95538$742ec2ed@news.sonic.net>
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
Message-ID: <50697b2c0907081622w11ed9275mcce5c0377cafd273@mail.gmail.com>

On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
> I have the "tkinter" problem and need some assistance to straighten it out.
> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in "step
> 1" and cannot import "_tkinter." I do not have that file on my computer, but
> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
> This ?python stuff is great, but the documentation frequently
> feels like it is just a bit out of my grasp. I realize that all of this is
> free but I understand the instructions on the web page to repair only to the
> point of confusion. I'm not an expert. How do I modify my python
> configuration? Is there a file that needs to be edited? Which setup.py file
> do I use? Make? or python setup.py build and python setup.py install?
> Thanks. I appreciate your help.

- How did you install Python?
- What Linux distro are you using?

Cheers,
Chris
-- 
http://blog.rebertia.com


From robert.kern at gmail.com  Wed Jul  8 19:29:26 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 08 Jul 2009 18:29:26 -0500
Subject: PyQt GUI
In-Reply-To: <60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
Message-ID: <h33a4m$ic$1@ger.gmane.org>

On 2009-07-08 18:10, Helvin wrote:

> Thanks for the fast replies! I will look into how to use VTK now.
> Where would I find VTK's explicit support for PyQt?

Wrapping/Python/vtk/qt4/ in the VTK sources.

> Because I have installed VTK (using its installer) and pyVTK (using
> its setup.py file), but how do I actually use it in my code? According
> to: http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521455.html,
> I have tried 'import vtk', but python can't find the vtk module.

Then you have not installed VTK's Python bindings correctly. Note that pyVTK is 
just a library for manipulating VTK files. The VTK Python bindings are part of 
VTK's distribution itself. Exactly how did you install VTK? Did you compile it 
yourself?

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From ldo at geek-central.gen.new_zealand  Wed Jul  8 19:49:54 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Thu, 09 Jul 2009 11:49:54 +1200
Subject: walking a directory with very many files
References: <5f51bc62-16fb-4e24-ac6c-1e5ea3ee596c@d38g2000prn.googlegroups.com>
	<mailman.1560.1245011753.8015.python-list@python.org>
	<pan.2009.06.15.04.56.07@REMOVE.THIS.cybersource.com.au>
	<234b19ac-7baf-4356-9fe5-37d00146d982@z9g2000yqi.googlegroups.com>
	<h19lpc$omc$2@lust.ihug.co.nz>
	<20090617091858.432f89ca@malediction>
	<eCZZl.19176$y61.15588@news-server.bigpond.net.au>
	<20090617110705.7e7c423f@malediction>
	<%Zv_l.19493$y61.5958@news-server.bigpond.net.au>
	<h1f987$1fe$7@lust.ihug.co.nz>
	<J_Q_l.19655$y61.10309@news-server.bigpond.net.au>
	<h1i83b$ojg$3@lust.ihug.co.nz>
	<0058d36a$0$9759$c3e8da3@news.astraweb.com>
	<h1qos2$ta2$1@services.telesweet.net>
	<pan.2009.06.24.02.20.10@REMOVE.THIS.cybersource.com.au>
	<h1scda$mrl$5@lust.ihug.co.nz>
	<kCk0m.406$ze1.243@news-server.bigpond.net.au>
Message-ID: <h33bb2$ges$1@lust.ihug.co.nz>

In message <kCk0m.406$ze1.243 at news-server.bigpond.net.au>, Lie Ryan wrote:

> Lawrence D'Oliveiro wrote:
>
>> ... certainly it is characteristic of GUIs to show you all 400,000 files
>> in a directory, or at least try to do so, and either hang for half an
>> hour or run out of memory and crash, rather than give you some
>> intelligent way of prefiltering the file display up front.
> 
> In many debugging cases, you don't even know what to filter ...

So pick a random sample to start with. Do you know of a GUI tool that can do 
that?



From mensanator at aol.com  Wed Jul  8 20:03:42 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 8 Jul 2009 17:03:42 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com>
Message-ID: <4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com>

On Jul 7, 12:47?am, Mensanator <mensana... at aol.com> wrote:
> On Jul 7, 12:16 am, casevh <cas... at gmail.com> wrote:
>
> > I discovered a serious bug with comparisons and have posted alpha2
> > which fixes that bug and adds Unicode support for Python 2.x
>
> > casevh
>
> Damn! I was just congatulating myself for pulling off
> a hat trick (there had been no point in downloading
> 3.x without gmpy so I have been putting it off):
>
> - installing Python 3.1
> - installing gmpy 1.10
> - converting my Collatz Function library to 3.1 syntax
>
> And it all worked smoothly, just had to add parentheses
> to my print statements, change xrange to range and all
> my / to // (the library is exclusively integer). I had
> gmpy running in my library on 3.1 in about 10 minutes.
>
> So I'll have to re-do the gmpy install. Shouldn't be
> any big deal.
>
> I started doing some real world tests. Generally, things
> look good (nothing crashes, timing looks not bad) but
> I'm getting some funny results on one of my tests, so
> I'll report back when I have more information.

As I said, I was getting funny results from one of my tests.

It seemed to work ok, but timing varied from 2 to 88 seconds,
which seemed odd. The other tests were generally consistent
for a given environment (cpu speed, OS, Python version, gmpy
version).

At some point I watched the memory usage profile from Windows.
On the same machine I have both Python 2.6 and 3.1 installed,
with the appropriate gmpy 1.10 version loaded for each.

In Python 2.6, it looks like this:

memory usage profile Python 2.6 gmpy 1.1 Vista

      /--------------\  /-------\ .....RESTART SHELL
     /               .\/         \
____/                .            \________
   .                 .
   .                 .
   start of RUN      start of RUN

The first "start of RUN" is the first time the test is run
(from IDLE). That change in usage represents about 700 MB
(I'm testing really BIG numbers, up to 500 million digits).

The memory remains allocated after the program terminates
(the flat plateau). When I run a second time, we see the
allocation dip, then climb back up to the plateau, so it
appears that the allocation never climbs above 1.1 GB.

Finally, doing a RESTART SHELL seems to completely free
the allocated memory. I assume this is normal behaviour.

With Python 3.1, it get this profile:

memory usage profile Python 3.1 gmpy 1.1 Vista

                         /-
                        / |
      /----------------/   \------\ .....RESTART SHELL
     /                 .           \
____/                  .            \___________
   .                   .
   .                   .
   start of RUN        start of RUN

Here, at the start of the second RUN, it appears that new
memory is allocated BEFORE the previous is cleared. Is this
a quirk in the way 3.1 behaves? Here, the peak usage climbs
to 1.8 GB which I think causes VM thrashing accounting for
the increased execution times.

My guess is that gmpy is provoking, but not causing this
behaviour.

The actual test is:

t0 = time.time()
n=10
for k in range(1,n):
  for i in range(1,n-2):
    print((str(cf.gmpy.numdigits(cf.Type12MH(k,i))).zfill(n)),end=' ')
  print()
print()
t1 = time.time()


The library function Type12MH is:

def Type12MH(k,i):
    """Find ith, kth Generation Type [1,2] Mersenne Hailstone using
the closed form equation

    Type12MH(k,i)
    k: generation
    i: member of generation
    returns Hailstone (a)
    """
    ONE = gmpy.mpz(1)
    TWO = gmpy.mpz(2)
    SIX = gmpy.mpz(6)
    NIN = gmpy.mpz(9)

    if (k<1) or (i<1): return 0

    i = gmpy.mpz(i)
    k = gmpy.mpz(k)

    # a = (i-1)*9**(k-1) + (9**(k-1) - 1)//2 + 1
    # return 2**(6*a - 1) - 1

    a = (i-ONE)*NIN**(k-ONE) + (NIN**(k-ONE) - ONE)//TWO + ONE
    return TWO**(SIX*a - ONE) - ONE

##  Sample runs
##
##  Test 1 - create numbers up to 500 million digits
##
##  0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##  0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##  0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##  0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##  0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##  0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##  0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##  0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##  0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##  15.5460000038
##  >>> ================================ RESTART
================================
##  >>>
##  0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##  0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##  0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##  0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##  0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##  0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##  0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##  0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##  0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##  3.06299996376



From psimon at sonic.net  Wed Jul  8 20:16:15 2009
From: psimon at sonic.net (Paul Simon)
Date: Wed, 8 Jul 2009 17:16:15 -0700
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
Message-ID: <4a5536d4$0$95520$742ec2ed@news.sonic.net>


"Chris Rebert" <clp2 at rebertia.com> wrote in message 
news:mailman.2863.1247095339.8015.python-list at python.org...
On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
> I have the "tkinter" problem and need some assistance to straighten it 
> out.
> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in 
> >"step
> 1" and cannot import "_tkinter." I do not have that file on my computer, 
> but
> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
> This python stuff is great, but the documentation frequently
> feels like it is just a bit out of my grasp. I realize that all of this is
> free but I understand the instructions on the web page to repair only to 
> the
> point of confusion. I'm not an expert. How do I modify my python
> configuration? Is there a file that needs to be edited? Which setup.py 
> file
> do I use? Make? or python setup.py build and python setup.py install?
> Thanks. I appreciate your help.

- How did you install Python?
- What Linux distro are you using?

Cheers,
Chris
-- 
http://blog.rebertia.com
I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
exactly how I installed Python.  Originally I had installed 2.5 from RPM but
2.6 was not available for my distro (2008.1) in RPM.  I downloaded something
from python.org and installed.  Not sure if it was tarball or zip file.

Paul




From casevh at gmail.com  Wed Jul  8 20:38:06 2009
From: casevh at gmail.com (casevh)
Date: Wed, 8 Jul 2009 17:38:06 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com> 
	<4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com>
Message-ID: <4ae1e16f-124b-49c8-8364-36c59419be9b@d32g2000yqh.googlegroups.com>

On Jul 8, 5:03?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 7, 12:47?am, Mensanator <mensana... at aol.com> wrote:
>
>
>
> > On Jul 7, 12:16 am, casevh <cas... at gmail.com> wrote:
>
> > > I discovered a serious bug with comparisons and have posted alpha2
> > > which fixes that bug and adds Unicode support for Python 2.x
>
> > > casevh
>
> > Damn! I was just congatulating myself for pulling off
> > a hat trick (there had been no point in downloading
> > 3.x without gmpy so I have been putting it off):
>
> > - installing Python 3.1
> > - installing gmpy 1.10
> > - converting my Collatz Function library to 3.1 syntax
>
> > And it all worked smoothly, just had to add parentheses
> > to my print statements, change xrange to range and all
> > my / to // (the library is exclusively integer). I had
> > gmpy running in my library on 3.1 in about 10 minutes.
>
> > So I'll have to re-do the gmpy install. Shouldn't be
> > any big deal.
>
> > I started doing some real world tests. Generally, things
> > look good (nothing crashes, timing looks not bad) but
> > I'm getting some funny results on one of my tests, so
> > I'll report back when I have more information.
>
> As I said, I was getting funny results from one of my tests.
>
> It seemed to work ok, but timing varied from 2 to 88 seconds,
> which seemed odd. The other tests were generally consistent
> for a given environment (cpu speed, OS, Python version, gmpy
> version).
>
> At some point I watched the memory usage profile from Windows.
> On the same machine I have both Python 2.6 and 3.1 installed,
> with the appropriate gmpy 1.10 version loaded for each.
>
> In Python 2.6, it looks like this:
>
> memory usage profile Python 2.6 gmpy 1.1 Vista
>
> ? ? ? /--------------\ ?/-------\ .....RESTART SHELL
> ? ? ?/ ? ? ? ? ? ? ? .\/ ? ? ? ? \
> ____/ ? ? ? ? ? ? ? ?. ? ? ? ? ? ?\________
> ? ?. ? ? ? ? ? ? ? ? .
> ? ?. ? ? ? ? ? ? ? ? .
> ? ?start of RUN ? ? ?start of RUN
>
> The first "start of RUN" is the first time the test is run
> (from IDLE). That change in usage represents about 700 MB
> (I'm testing really BIG numbers, up to 500 million digits).
>
> The memory remains allocated after the program terminates
> (the flat plateau). When I run a second time, we see the
> allocation dip, then climb back up to the plateau, so it
> appears that the allocation never climbs above 1.1 GB.
>
> Finally, doing a RESTART SHELL seems to completely free
> the allocated memory. I assume this is normal behaviour.
>
> With Python 3.1, it get this profile:
>
> memory usage profile Python 3.1 gmpy 1.1 Vista
>
> ? ? ? ? ? ? ? ? ? ? ? ? ?/-
> ? ? ? ? ? ? ? ? ? ? ? ? / |
> ? ? ? /----------------/ ? \------\ .....RESTART SHELL
> ? ? ?/ ? ? ? ? ? ? ? ? . ? ? ? ? ? \
> ____/ ? ? ? ? ? ? ? ? ?. ? ? ? ? ? ?\___________
> ? ?. ? ? ? ? ? ? ? ? ? .
> ? ?. ? ? ? ? ? ? ? ? ? .
> ? ?start of RUN ? ? ? ?start of RUN
>
> Here, at the start of the second RUN, it appears that new
> memory is allocated BEFORE the previous is cleared. Is this
> a quirk in the way 3.1 behaves? Here, the peak usage climbs
> to 1.8 GB which I think causes VM thrashing accounting for
> the increased execution times.
>

Hmmm. It looks like memory is not being release properly. I don't see
that behavior under Linux. The running time is a very consistent 1.35
seconds. I'm traveling at the moment so it will be at least a week
before I can test under Windows.

Thanks for the report. I'll try to see if I can figure out what is
going on.

casevh
> My guess is that gmpy is provoking, but not causing this
> behaviour.
>
> The actual test is:
>
> t0 = time.time()
> n=10
> for k in range(1,n):
> ? for i in range(1,n-2):
> ? ? print((str(cf.gmpy.numdigits(cf.Type12MH(k,i))).zfill(n)),end=' ')
> ? print()
> print()
> t1 = time.time()
>
> The library function Type12MH is:
>
> def Type12MH(k,i):
> ? ? """Find ith, kth Generation Type [1,2] Mersenne Hailstone using
> the closed form equation
>
> ? ? Type12MH(k,i)
> ? ? k: generation
> ? ? i: member of generation
> ? ? returns Hailstone (a)
> ? ? """
> ? ? ONE = gmpy.mpz(1)
> ? ? TWO = gmpy.mpz(2)
> ? ? SIX = gmpy.mpz(6)
> ? ? NIN = gmpy.mpz(9)
>
> ? ? if (k<1) or (i<1): return 0
>
> ? ? i = gmpy.mpz(i)
> ? ? k = gmpy.mpz(k)
>
> ? ? # a = (i-1)*9**(k-1) + (9**(k-1) - 1)//2 + 1
> ? ? # return 2**(6*a - 1) - 1
>
> ? ? a = (i-ONE)*NIN**(k-ONE) + (NIN**(k-ONE) - ONE)//TWO + ONE
> ? ? return TWO**(SIX*a - ONE) - ONE
>
> ## ?Sample runs
> ##
> ## ?Test 1 - create numbers up to 500 million digits
> ##
> ## ?0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
> 0000000013
> ## ?0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
> 0000000107
> ## ?0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
> 0000000952
> ## ?0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
> 0000008560
> ## ?0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
> 0000077028
> ## ?0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
> 0000693246
> ## ?0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
> 0006239209
> ## ?0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
> 0056152869
> ## ?0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
> 0505375816
> ##
> ## ?15.5460000038
> ## ?>>> ================================ RESTART
> ================================
> ## ?>>>
> ## ?0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
> 0000000013
> ## ?0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
> 0000000107
> ## ?0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
> 0000000952
> ## ?0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
> 0000008560
> ## ?0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
> 0000077028
> ## ?0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
> 0000693246
> ## ?0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
> 0006239209
> ## ?0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
> 0056152869
> ## ?0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
> 0505375816
> ##
> ## ?3.06299996376



From no.email at please.post  Wed Jul  8 21:20:10 2009
From: no.email at please.post (kj)
Date: Thu, 9 Jul 2009 01:20:10 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mailman.2671.1246866295.8015.python-list@python.org>
Message-ID: <h33gka$19p$1@reader1.panix.com>

In <mailman.2671.1246866295.8015.python-list at python.org> Martin Vilcans <martin at librador.com> writes:

>On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
>> I'm will be teaching a programming class to novices, and I've run
>> into a clear conflict between two of the principles I'd like to
>> teach: code clarity vs. code reuse. =A0I'd love your opinion about
>> it.

>In general, code clarity is more important than reusability.
>Unfortunately, many novice programmers have the opposite impression. I
>have seen too much convoluted code written by beginners who try to
>make the code generic. Writing simple, clear, to-the-point code is
>hard enough as it is, even when not aiming at making it reusable.

>If in the future you see an opportunity to reuse the code, then and
>only then is the time to make it generic.

>YAGNI is a wonderful principle.

Thanks!

kynn



From no.email at please.post  Wed Jul  8 21:21:22 2009
From: no.email at please.post (kj)
Date: Thu, 9 Jul 2009 01:21:22 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>	<f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
	<mailman.2673.1246866666.8015.python-list@python.org>
	<fMKdnf0dlOXTcMzXnZ2dnUVZ_t2dnZ2d@pdx.net>
Message-ID: <h33gmi$19p$2@reader1.panix.com>

In <fMKdnf0dlOXTcMzXnZ2dnUVZ_t2dnZ2d at pdx.net> Scott David Daniels <Scott.Daniels at Acm.Org> writes:

>First, a quote which took me a bit to find:
>     Thomas William K??rner paraphrasing Polya and Svego
>     in A Companion to Analysis:
>         Recalling that 'once is a trick, twice is a method,
>         thrice is a theorem, and four times a theory,' we
>         seek to codify this insight.

Good stuff.

>Let us apply this insight:
>     Suppose in writing code, we pretty much go with that.
>A method is something you notice, a theorem is a function, and
>a theory is a generalized function.

>Even though we like DRY ("don't repeat yourself") as a maxim, let
>it go the first time and wait until you see the pattern (a possible
>function).  I'd go with a function first, a pair of functions, and
>only then look to abstracting the function.

Thanks!

kynn


From jcd at sdf.lonestar.org  Wed Jul  8 22:10:47 2009
From: jcd at sdf.lonestar.org (J. Clifford Dyer)
Date: Wed, 08 Jul 2009 22:10:47 -0400
Subject: count
In-Reply-To: <7xbpnuzw4u.fsf@ruckus.brouhaha.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>  <7xbpnuzw4u.fsf@ruckus.brouhaha.com>
Message-ID: <1247105447.4532.8.camel@mctell>

On Wed, 2009-07-08 at 14:45 -0700, Paul Rubin wrote:
> aahz at pythoncraft.com (Aahz) writes:
> > >Avoid that len(tuple(g)), use something like the following, it's lazy
> > >and saves some memory.
> > The question is whether it saves time, have you tested it?
> 
> len(tuple(xrange(100000000))) ... hmm.

timer.py
--------
from datetime import datetime

def tupler(n):
    return len(tuple(xrange(n)))

def summer(n):
    return sum(1 for x in xrange(n))

def test_func(f, n):
    print f.__name__,
    start = datetime.now()
    print f(n)
    end = datetime.now()
    print "Start: %s" % start
    print "End: %s" % end
    print "Duration: %s" % (end - start,)

if __name__ == '__main__':
    test_func(summer, 10000000)
    test_func(tupler, 10000000)
    test_func(summer, 100000000)
    test_func(tupler, 100000000)

$ python timer.py
summer 10000000
Start: 2009-07-08 22:02:13.216689
End: 2009-07-08 22:02:15.855931
Duration: 0:00:02.639242
tupler 10000000
Start: 2009-07-08 22:02:15.856122
End: 2009-07-08 22:02:16.743153
Duration: 0:00:00.887031
summer 100000000
Start: 2009-07-08 22:02:16.743863
End: 2009-07-08 22:02:49.372756
Duration: 0:00:32.628893
Killed
$ 

Note that "Killed" did not come from anything I did.  The tupler just
bombed out when the tuple got too big for it to handle.  Tupler was
faster for as large an input as it could handle, as well as for small
inputs (test not shown).



From no.email at please.post  Wed Jul  8 22:19:25 2009
From: no.email at please.post (kj)
Date: Thu, 9 Jul 2009 02:19:25 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
Message-ID: <h33k3d$2uu$1@reader1.panix.com>

In <mailman.2700.1246895025.8015.python-list at python.org> Tim Rowe <digitig at gmail.com> writes:

>2009/7/4 kj <no.email at please.post>:

>> Precisely. =A0As I've stated elsewhere, this is an internal helper
>> function, to be called only a few times under very well-specified
>> conditions. =A0The assert statements checks that these conditions
>> are as intended. =A0I.e. they are checks against the module writer's
>> programming errors.

>Good for you. I'm convinced that you have used the assertion
>appropriately, and the fact that so many here are unable to see that
>looks to me like a good case for teaching the right use of assertions.
>For what it's worth, I read assertions at the beginning of a procedure
>as part of the specification of the procedure, and I use them there in
>order to document the procedure. An assertion in that position is for
>me a statement to the user of the procedure "it's your responsibility
>to make sure that you never call this procedure in such a way as to
>violate these conditions". They're part of a contract, as somebody
>(maybe you) pointed out.

>As somebody who works in the safety-critical domain, it's refreshing
>to see somebody teaching students to think about the circumstances in
>which a procedure can legitimately be called. The hostility you've
>received to that idea is saddening, and indicative of why there's so
>much buggy software out there.

Thanks for the encouragement.

When I teach programming, the students are scientists.  For the
stuff they do, correctness of the code trumps everything else.  I
teach them to view assertions as way of translating their assumptions
into code.  And by this I mean not only assumptions about the
correctness of their code (the typical scope of assertions), but
also, more broadly, assumptions about the data that they are dealing
with (which often comes from external sources with abysmal quality
control).

My scientific code is jam-packed with assertions.  I can't count
the number of times that one such lowly assertion saved me from a
silent but potentially disastrous bug.  And yes I find it distressing
that so so few programmers in my line of work use assertions at
all.

kynn


From vel.accel at gmail.com  Wed Jul  8 22:23:53 2009
From: vel.accel at gmail.com (dieter)
Date: Wed, 8 Jul 2009 19:23:53 -0700 (PDT)
Subject: PyGtk Depends on Numeric
Message-ID: <1ebe9314-9434-459a-bd3e-2b2386a35f1b@n11g2000yqb.googlegroups.com>

Get with the times people and port to numpy. :P
Don't you think its about time?

~Pete


From jpablo.romero at gmail.com  Wed Jul  8 22:55:53 2009
From: jpablo.romero at gmail.com (=?ISO-8859-1?Q?Juan_Pablo_Romero_M=E9ndez?=)
Date: Wed, 8 Jul 2009 21:55:53 -0500
Subject: PyQt GUI
In-Reply-To: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
Message-ID: <e6507ac70907081955s7d69c816gecf41aeb42502269@mail.gmail.com>

I use OpenInventor (Coin3d) which have a python binding called "pivy".
It works great.

http://pivy.coin3d.org/

Juan Pablo

2009/7/8 Helvin <helvinlui at gmail.com>:
> Hi experts!
>
> I'm developing a GUI for a software using PyQT, and need 3D
> visualization. Should I use PyOpenGL or VTK?
> I understand that the PyQt package comes with a opengl module. What
> else would I need? I think I need to download opengl. but how? where?
> I have VTK and pyVTK installed, but I don't know how to use it in my
> code, as when I run it, an error says it can't find the vtk module.
>
> Help would be sooooo appreciated!
> Helvin
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From fatkinson at mishmash.com  Wed Jul  8 23:53:12 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Wed, 08 Jul 2009 20:53:12 -0700
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
Message-ID: <cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>

On Wed, 08 Jul 2009 12:29:54 +0200, Piet van Oostrum <piet at cs.uu.nl>
wrote:

>Something like:
>
>#! /usr/bin/env python
>
>import cgi
>from os import getenv
>
>print "Content-type: text/html"
>print
>
>ipaddr = (getenv("HTTP_CLIENT_IP") or
>      getenv("HTTP_X_FORWARDED_FOR") or
>      getenv("HTTP_X_FORWARDED_FOR") or
>      getenv("REMOTE_ADDR") or
>      "UNKNOWN")
>
>print ipaddr

That did it.  

I wonder why they don't just have a function to return it instead of
putting you through all of that?  

At any rate, it works.  

Regards, 




                                                      Fred 


From nobody at nowhere.com  Thu Jul  9 00:38:32 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 09 Jul 2009 05:38:32 +0100
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
	<cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>
Message-ID: <pan.2009.07.09.04.38.32.94000@nowhere.com>

On Wed, 08 Jul 2009 20:53:12 -0700, Fred Atkinson wrote:

>>ipaddr = (getenv("HTTP_CLIENT_IP") or
>>      getenv("HTTP_X_FORWARDED_FOR") or
>>      getenv("HTTP_X_FORWARDED_FOR") or
>>      getenv("REMOTE_ADDR") or
>>      "UNKNOWN")
>>
>>print ipaddr
> 
> That did it.  
> 
> I wonder why they don't just have a function to return it instead of
> putting you through all of that?  

There's no unambiguous definition of "client IP", so you have to choose
which definition you want.

REMOTE_ADDR is set to the actual IP address from which the connection
originated (from getpeername()). If the connection was made via a proxy,
REMOTE_ADDR will contain the IP address of the proxy.

The others are set from HTTP headers. Proxies often add Client-IP
or X-Forwarded-For headers to indicate the originating IP address. OTOH,
there's no way to know if the headers are accurate; nuisance users may
add these headers to confuse poorly-conceived banning mechanisms.



From sajmikins at gmail.com  Thu Jul  9 01:05:57 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Wed, 8 Jul 2009 22:05:57 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
Message-ID: <b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>

(I wanted to reply to a few messages in one post so I quoted them all
below. Let me know if this is bad etiquette.)

On Jul 8, 8:23 am, kj <no.em... at please.post> wrote:
> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5... at q11g2000yqi.googlegroups.com> Simon Forman <sajmik... at gmail.com> writes:
>
> >Frankly, I'm of the impression that it's a mistake not to start
> >teaching programming with /the bit/ and work your way up from there.
> >I'm not kidding. I wrote a (draft) article about this: "Computer
> >Curriculum"http://docs.google.com/View?id=dgwr777r_31g4572gp4
> >I really think the only good way to teach computers and programming is
> >to start with a bit, and build up from there. "Ontology recapitulates
> >phylogeny"
>
> I happen to be very receptive to this point of view.  I had the
> benefit of that sort of training (one of the first computer courses
> I took started, believe it or not, with Turing machines, through
> coding in machine language, and compiler theory, and all the way
> up to dabbling with Unix!), and I suspect that the reason it is
> sometimes difficult for me to explain even relatively simple-looking
> things to others is that I have this background that I unconsciously,
> and incorrectly, take for granted in others...  There is this

Yes!  Once the concepts become so familiar that you call them
"intuitive" it seems to be very difficult to remember what they were
like before.

Something like "a = b" becomes "obvious" only after you've
internalized the preceding concepts.


> persistent idea "out there" that programming is a very accessible
> skill, like cooking or gardening, anyone can do it, and even profit
> from it, monetarily or otherwise, etc., and to some extent I am

Programming is not like any other human activity.  I've been reading
some of Prof. Dijkstra's EWDs in the last few days.  In one [1] he
says, "automatic computers embody not only one radical novelty but two
of them", to wit: First, the huge scales that must be understood,
"from a bit to a few hundred megabytes, from a microsecond to a half
an hour of computing"; and second, "that the automatic computer is our
first large-scale digital device" which our until-now overwhelmingly
analog experience does not prepare us to deal with well.

He talks about how "when all is said and done, the only thing
computers can do for us is to manipulate symbols and produce results
of such manipulations" and he emphasises the "uninterpreted" nature of
mechanical symbol manipulation, i.e. that the machine is doing it
mindlessly.

Dijkstra[1]: "It is true that the student that has never manipulated
uninterpreted formulae quickly realizes that he is confronted with
something totally unlike anything he has ever seen before. But
fortunately, the rules of manipulation are in this case so few and
simple that very soon thereafter he makes the exciting discovery that
he is beginning to master the use of a tool that, in all its
simplicity, gives him a power that far surpasses his wildest
dreams." [1]


> actively contributing to this perception by teaching this course
> to non-programmers (experimental biologists to be more precise),

Experimental biologists?  Well that's probably harmless.  Mostly
harmless.

> but maybe this idea is not entirely true...  Maybe, to get past
> the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest
> that real computer scientists learn about in their formal training...
>
> kj

If you're never exposed to that constellation of concepts that
underpins "mechanical symbol manipulation" you are adrift in a sea
("c", ha ha) of abstractions.

However, if you /are/ exposed to the "so few and simple" rules of
manipulation the gates (no pun intended) to the kingdom are thrown
wide.


On Jul 8, 9:10 am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Wed, 08 Jul 2009 12:23:50 +0000, kj wrote:
> > I happen to be very receptive to this point of view.
> [...]
> > There is this persistent idea "out there" that
> > programming is a very accessible skill, like cooking or gardening,
> > anyone can do it, and even profit from it, monetarily or otherwise,
> > etc., and to some extent I am actively contributing to this perception
> > by teaching this course to non-programmers (experimental biologists to
> > be more precise), but maybe this idea is not entirely true...
>
> There is some evidence that 30-60% of people simply cannot learn to
> program, no matter how you teach them:
>
> http://www.codinghorror.com/blog/archives/000635.html
> http://www.cs.mdx.ac.uk/research/PhDArea/saeed/

Thank you! That's exactly the paper that prompted me to write the
article I mentioned. (Now I don't have to go find the link myself.
Win!)

I don't buy it: I believe strongly that any normal person can learn to
program, to manipulate symbols to create formulae that guide the
machine in its uninterpreted symbol manipulation.

I find it significant that in the paper [2] they say, "Formal logical
proofs, and therefore programs ? formal logical proofs that particular
computations are possible, expressed in a formal system called a
programming language ? are utterly meaningless. To write a computer
program you have to come to terms with this, to accept that whatever
you might want the program to mean, the machine will blindly follow
its meaningless rules and come to some meaningless conclusion. In the
test the consistent group showed a pre-acceptance of this fact: they
are capable of seeing mathematical calculation problems in terms of
rules, and can follow those rules wheresoever they may lead. The
inconsistent group, on the other hand, looks for meaning where it is
not."

In other words the people who don't understand computers, don't
understand computers.

I think that "first hump" people can become "second hump" people but
that it requires teaching them the foundations first, not confronting
them with such incredible novelties as "a = b" and saying in effect,
"here you go buddy, sink or swim."

Quoting Dijkstra again [1]: "Before we part, I would like to invite
you to consider the following way of doing justice to computing's
radical novelty in an introductory programming course.

"On the one hand, we teach what looks like the predicate calculus, but
we do it very differently from the philosophers. In order to train the
novice programmer in the manipulation of uninterpreted formulae, we
teach it more as boolean algebra, familiarizing the student with all
algebraic properties of the logical connectives. To further sever the
links to intuition, we rename the values {true, false} of the boolean
domain as {black, white}.

"On the other hand, we teach a simple, clean, imperative programming
language, with a skip and a multiple assignment as basic statements,
with a block structure for local variables, the semicolon as operator
for statement composition, a nice alternative construct, a nice
repetition and, if so desired, a procedure call. To this we add a
minimum of data types, say booleans, integers, characters and strings.
The essential thing is that, for whatever we introduce, the
corresponding semantics is defined by the proof rules that go with
it."

Imagine my surprise: he's saying (with immensely greater brilliance
and eloquence) much what I said in my little article. The major
difference from what he's outlined is that I think the students should
implement the imperative programming language themselves in Forth, but
the gist is the same.


> I'm sympathetic to the idea, but not entirely convinced. Perhaps the
> problem isn't with the students, but with the teachers, and the
> languages:
>
> http://www.csse.monash.edu.au/~damian/papers/PDF/SevenDeadlySins.pdf
>
> (My money is that it's a little of both.)

Hmm, that paper contains some good insights IMO, but I think they're
still missing the big picture, so to speak.

Really I suspect it's a case of "Programming languages considered
harmful."

The core abstractions of [mechanical] computation are just not that
complicated.  You can teach them to anybody in about a half an hour,
drunk. I have.

After that, if they're interested, there is a smooth easy path to
"higher" abstractions: parsing, compiling, tree traversal and
transformation.  (It is said that possession is 9/10s of the law, in
the same vein I would claim parsing is 9/10s of computer programming.)

I am beginning to suspect that concrete static (in the sense of
"standard" language specifications) languages are part of the
problem.  Everyone gets so caught up in programming via languages that
you get, well, people trying to teach "Computer Programming" as if it
were only necessary to grok a language, rather than grokking /symbol
manipulation/ itself.

(Did you read that last paragraph and think, "Well how the heck else
are you supposed to program a computer if not in a computer
language?"?  If so, well, that is kind of my point.)


> > Maybe, to
> > get past the most amateurish level, one has to, one way or another, come
> > face-to-face with bits, compilers, algorithms, and all the rest that
> > real computer scientists learn about in their formal training...
>
> The "No True Scotsman" fallacy.
>
> There's nothing amateurish about building software applications that
> work, with well-designed interfaces and a minimum of bugs, even if you've
> never heard of Turing Machines.
>
> --
> Steven

I beg to differ. I recall a conversation with a co-worker who had
"learned" to program using PHP.  Another co-worker and I were trying
to convince him that there was a good reason to differentiate between
hash tables and arrays. He didn't even know that they were different
"things".

I remember telling him, "between the metal and the desktop there is
nothing but layers of abstraction.  We use different names precisely
because of different behaviours."

He made "well-designed interfaces", but "amateurish" is about the
nicest thing I would have called him.

As for "a minimum of bugs"... sigh. The "minimum of bugs" is zero, if
you derive your "uninterpreted formulae" /correctly/.  Deriving
provably correct "programs" should be what computer science and
computer education are all about (not "java vocational training" as
Alan Kay once decried.)

Again with Dijkstra[3]: "The prime paradigma of the pragmatic designer
is known as "poor man's induction", i.e. he believes in his design as
long as "it works", i.e. until faced with evidence to the contrary.
(He will then "fix the design".) The scientific designer, however,
believes in his design because he understands why it will work under
all circumstances. The transition from pragmatic to scientific design
would indeed be a drastic change within the computer industry."

"Obviously no errors" is the goal to strive for, and I am comfortable
calling anyone an amateur who prefers "no obvious errors."  (Actually
that's a little harsh on the amateurs, "ama" meaning love, "amateur"
is one who does something for love of it.)


On Jul 8, 9:27 am, kj <no.em... at please.post> wrote:
> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5... at q11g2000yqi.googlegroups.com> Simon Forman <sajmik... at gmail.com> writes:
>
> >I'm not kidding. I wrote a (draft) article about this: "Computer
> >Curriculum"http://docs.google.com/View?id=dgwr777r_31g4572gp4
>
> Very cool.
>
> kj

Hey, thank you!


On Jul 8, 9:47 am, Paul Moore <p.f.mo... at gmail.com> wrote:
> 2009/7/8 kj <no.em... at please.post>:
>
> > There is this
> > persistent idea "out there" that programming is a very accessible
<snip>
> > that real computer scientists learn about in their formal training...
>
> Look at it another way. Experimental biologists don't want to program,
> they want to use computers to do experimental biology. It's a tool,
> and they (quite reasonably) don't *care* about robustness,
> portability, etc. Or even about programming, to be honest.

I'd say it's just the opposite: to "use computers to do experimental
biology" they want to instruct that machine to manipulate their
(meaningful to them but meaningless to it) symbols in useful ways.
This is nothing more or less than programming.

The fact that they need to learn all sorts of details of a programming
language to do that is NOT because they can't grok programming. It's
because computer scientists have put too many layers of abstraction on
top of the "pure" symbol manipulation and then forgotten what they
have done.

I have a very nice book "Introduction to Programming and Problem
Solving with Pascal" that I picked up for $0.50 at a used bookstore
not long ago.  It says, right on page 201, in the chapter on "Running,
Debugging, and Testing Programs":

"One of the nice features of programming in a high-level language like
Pascal is that it can be done with almost a total lack of
understanding of what a computer is and how it actually operates.
[...] There is no reason why someone who wants to write a computer
program should have to understand the electronic circuitry of a
computer, any more than someone learning to drive a car should have to
understand how the internal combustion engine works."

I think that's exactly wrong. What you're doing with computers doesn't
change from the bit to the high-level language.  It's all symbol
manipulation according to the same set of rules, all the way up.  The
elaboration becomes involved as you go up but the process does not
change qualitatively.


> In the context of the original question, it's entirely reasonable (in
> my view) to tell this audience "if the code does something weird you
> don't understand, either ignore it and find another way or dig into
> the manuals and experiment if you care". They'd very quickly find a =
> a + b as a less confusing alternative to a += b. (As has been pointed
> out earlier, to some extent a += b is quite an advanced construct -
> after all, it's essentially an optimisation of a = a + b).

On that point I completely agree. The language is getting in the way
of the programming.

> Biologists don't expect me to understand their discipline before I can
> plant seeds in my garden, after all. (And when I do plant seeds, I
> usually get far more surprising results than I could get from a += b
> :-))
>
> Paul.

The discipline of programming is different than biology. It's
incredibly simple yet profound if it's taught as what it is, i.e.
automatic symbol manipulation.

No scientist is a stranger to logic and reasoned argument.  They
shouldn't be strangers to telling their mechanical brains what to
"reason" about.  Learning to program should be /easy/ for someone who
basically already gets it.

Wow, long post.

(Oh, and, er, it's ONTOGENY not Ontology that recapitulates phylogeny.
Heh. My bad.)

[1] "On the cruelty of really teaching computing science"
http://www.cs.utexas.edu/~EWD/transcriptions/EWD10xx/EWD1036.html


[2] "The camel has two humps"
http://www.cs.mdx.ac.uk/research/PhDArea/saeed/paper1.pdf


[3] "Can computing science save the computer industry?"
http://www.cs.utexas.edu/users/EWD/transcriptions/EWD09xx/EWD920.html


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 02:14:18 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 03:14:18 -0300
Subject: Python Error from Apress book
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
	<4A5345B1.8050306@ieee.org>
	<op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
	<4A54687A.6010004@ieee.org>
Message-ID: <op.uwsd94ipx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 06:35:54 -0300, Dave Angel <davea at ieee.org> escribi?:
> Gabriel Genellina wrote:
>> Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
>>> Gabriel Genellina wrote:
>>>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com>  
>>>> escribi?:
>>
>>>>> When I try to run the command as outlined in
>>>>> the book "simple_markup2.py < test_input.txt > test_output.html i  
>>>>> get the
>>>>> following error every time.
>>>>>
>>>>> IOError: [Errno 9] Bad file descriptor
>>
>> I think the error depends on the specific OS version/service pack. But  
>> at least on XP this appears to fix it:
>>
>> http://support.microsoft.com/kb/321788/en-us
>>
> Thanks for the link.  Looking at that one, it indicates that Windows  
> 2000 fixed it in SP4, and XP fixed it in Sp1.  But I'm already running  
> XP SP3, so I wonder if it's something new.

I'm using XP SP3 too. Before applying the registry fix, stdout and stderr  
were working fine, but not stdin. After making the registry change, stdin  
works too.
I didn't notice the issue with stdin until now (I don't use stdin very  
often)

-- 
Gabriel Genellina



From helvinlui at gmail.com  Thu Jul  9 02:27:53 2009
From: helvinlui at gmail.com (Helvin)
Date: Wed, 8 Jul 2009 23:27:53 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
Message-ID: <5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>

On Jul 9, 11:29?am, Robert Kern <robert.k... at gmail.com> wrote:
> On 2009-07-08 18:10, Helvin wrote:
>
> > Thanks for the fast replies! I will look into how to use VTK now.
> > Where would I find VTK's explicit support for PyQt?
>
> Wrapping/Python/vtk/qt4/ in the VTK sources.
>
> > Because I have installed VTK (using its installer) and pyVTK (using
> > its setup.py file), but how do I actually use it in my code? According
> > to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
> > I have tried 'import vtk', but python can't find the vtk module.
>
> Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
> just a library for manipulating VTK files. The VTK Python bindings are part of
> VTK's distribution itself. Exactly how did you install VTK? Did you compile it
> yourself?
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
> ? that is made terrible by our own mad attempt to interpret it as though it had
> ? an underlying truth."
> ? ?-- Umberto Eco

You mean, when I download VTK, the VTK Python bindings come with it?
I downloaded VTK from:http://vtk.org/files/release/5.4/

I downloaded pyVTK from: http://pypi.python.org/pypi/PyVTK/0.4.67
And then installed it by the command 'python setup.py install'
according to: http://cens.ioc.ee/projects/pyvtk/
I understand that this command runs the file called 'setup.py' that
came with the pyVTK download.

Thanks so much for your help! I am very desperate now...

Helvin


From greg at cosc.canterbury.ac.nz  Thu Jul  9 02:29:26 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Thu, 09 Jul 2009 18:29:26 +1200
Subject: tough-to-explain Python
In-Reply-To: <mailman.2847.1247068773.8015.python-list@python.org>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>
	<mailman.2847.1247068773.8015.python-list@python.org>
Message-ID: <7blh0eF23r79rU1@mid.individual.net>

Dave Angel wrote:
> By the time I graduated, I had five six-level languages
                                       ^^^

Are they languages that you have to edit using vi? :-)

-- 
Greg


From morten.aasnes at gmail.com  Thu Jul  9 02:32:56 2009
From: morten.aasnes at gmail.com (Morten Nygaard Aasnes)
Date: 9 Jul 2009 06:32:56 GMT
Subject: Pydev 1.4.7 Released
References: <mailman.2861.1247094510.8015.python-list@python.org>
Message-ID: <7blh8oF2367ioU2@mid.individual.net>

On 2009-07-08, Fabio Zadrozny <fabiofz at gmail.com> wrote:
> Hi All,
>
> Pydev and Pydev Extensions 1.4.7 have been released
>
> Details on Pydev Extensions: http://www.fabioz.com/pydev
> Details on Pydev: http://pydev.sf.net
> Details on its development: http://pydev.blogspot.com

Nice! Will this work in Eclipse 3.5 as well?

-- 
Morten Nygaard ?snes   http://twitter.com/mortenaa   http://identi.ca/mortenaa


From stefan_ml at behnel.de  Thu Jul  9 02:42:06 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Thu, 09 Jul 2009 08:42:06 +0200
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <7xd48bdn73.fsf@ruckus.brouhaha.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<7xd48bdn73.fsf@ruckus.brouhaha.com>
Message-ID: <4a55913f$0$31874$9b4e6d93@newsspool3.arcor-online.net>

Paul Rubin wrote:
> Daniel Austria writes:
>> just one question. How can i remove all 0 values in a list? 
> 
> I prefer:
> 
>    newlist = list(x for x in oldlist if x != 0)
> 
> to the square bracket list comprehension that a few people have
> suggested.  This is because in python 2.x, the listcomp "leaks" its
> index variable into the surrounding scope, but the generator
> expression above doesn't.

As you indicated, that's been fixed in Py3, though. So if your code works
in Py3.x, you can be somewhat sure that the leak doesn't have side effects.
Plus, it's pretty easy to ignore those leaks as long as you use a suitable
name for the loop variable.

Also note that the performance characteristics may not be identical in both
cases, depending on where you run your code. Cython, for example, will
write a list comprehension out as a rather straight C loop, but when we
implement generator expressions in Cython, it may have to get turned into a
generator function instead of a loop, so that you'd get a much larger
overhead than for the plain list comprehension (although in the simple case
above it would likely get optimised away).

CPython shows a similar difference:

$ python3.1 -m timeit '[x for x in range(1000) if x]'
10000 loops, best of 3: 170 usec per loop
$ python3.1 -m timeit -s 'r=[i%2 for i in range(2000)]' \
				'[x for x in r if x]'
1000 loops, best of 3: 222 usec per loop

$ python3.1 -m timeit 'list(x for x in range(1000) if x)'
1000 loops, best of 3: 227 usec per loop
$ python3.1 -m timeit -s 'r=[i%2 for i in range(2000)]' \
				'list(x for x in r if x)'
1000 loops, best of 3: 280 usec per loop


Not that I'd consider those numbers worth bothering...

Stefan


From Lacrima.Maxim at gmail.com  Thu Jul  9 02:50:37 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Wed, 8 Jul 2009 23:50:37 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
Message-ID: <379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>

On Jul 8, 10:54?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Lacrima <Lacrima.Ma... at gmail.com> (L) wrote:
> >L> Hello!
> >L> I have just started using Emacs to write python scripts.
> >L> I installed python-mode.el
> >L> Then I just tried this code:
> >L> print 'hello world'
> >L> When I press C-c RET, new blank window is opened and emacs says:
> >L> (Shell command succeeded with no output)
> >L> So where is my 'hello world'?
> >L> When I do C-c C-c, it prints 'hello world' successfully.
> >L> Why in the first case I get no output?
>
> Can you check in the buffer where you have the python code what command
> C-c RET is bound to?
> With C-h k C-c RET
>
> Shell command succeeded with no output suggests that is has a different
> binding than the standard one in python-mode.
>
> Did you happen to name your file 'test' or 'test.py?
>
> C-c RET does an import and 'import test' imports a standard module test.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

Hi, Piet!

Thanks for your reply!
My file name is 'trains.py'.
When I do C-h k C-c RET, it shows me help from manual: "C-c RET runs
the command py-execute-import-or-reload
   which is an interactive Lisp function in `python-mode'..." and so
on.

And still when I do C-c RET, I receive "(Shell command succeeded with
no output)"

Any more help would be really appreciated, because I am newbie with
Emacs.

With regards, Max


From reddy.mrp at gmail.com  Thu Jul  9 03:17:52 2009
From: reddy.mrp at gmail.com (m.reddy prasad reddy)
Date: Thu, 9 Jul 2009 12:47:52 +0530
Subject: can i write a assemly language programs in python
Message-ID: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>

can any one tell me how to write assembly language programs in python...if
no is there any other way to write the programs in python

Reddi prasad reddy
ph.no:09958083797
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/ac092206/attachment.html>

From futurebase at gmx.at  Thu Jul  9 03:22:43 2009
From: futurebase at gmx.at (Daniel Austria)
Date: Thu, 9 Jul 2009 00:22:43 -0700 (PDT)
Subject: ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<7xd48bdn73.fsf@ruckus.brouhaha.com>
	<4a55913f$0$31874$9b4e6d93@newsspool3.arcor-online.net>
Message-ID: <4dcaab15-2d2d-4d7c-bd93-5e7f931cb369@j32g2000yqh.googlegroups.com>

Thanks a lot for your advices,

i decided to use the filter() method to sort out the 0.
i can ?t use the sum() function cause i need the list afterwards ....


best,
Dan


From reddy.mrp at gmail.com  Thu Jul  9 03:25:17 2009
From: reddy.mrp at gmail.com (m.reddy prasad reddy)
Date: Thu, 9 Jul 2009 12:55:17 +0530
Subject: i need immediate help from u
Message-ID: <a97ce0940907090025v7734dd5braa035ecbe92633f6@mail.gmail.com>

i m new this community .;
can any one send me the solution for writing the assembly language programs
in python
my mail ID:redd.mrp at gmail.com <ID%3Aredd.mrp at gmail.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/c440cdb1/attachment.html>

From __peter__ at web.de  Thu Jul  9 03:29:04 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 09 Jul 2009 09:29:04 +0200
Subject: regex help
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
Message-ID: <h34680$kme$02$1@news.t-online.com>

David wrote:

> <td>&nbsp;</td>
> 
> <td width="1%" class=key>Open:
> </td>
> <td width="1%" class=val>5.50
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>Mkt Cap:
> </td>
> <td width="1%" class=val>6.92M
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>P/E:
> </td>
> <td width="1%" class=val>21.99
> </td>
> 
> 
> I want to extract the open, mkt cap and P/E values - but apart from
> doing loads of indivdual REs which I think would look messy, I can't
> think of a better and neater looking way. Any ideas?

>>> from BeautifulSoup import BeautifulSoup
>>> bs = BeautifulSoup("""<td>&nbsp;</td>
...
... <td width="1%" class=key>Open:
... </td>
... <td width="1%" class=val>5.50
... </td>
... <td>&nbsp;</td>
... <td width="1%" class=key>Mkt Cap:
... </td>
... <td width="1%" class=val>6.92M
... </td>
... <td>&nbsp;</td>
... <td width="1%" class=key>P/E:
... </td>
... <td width="1%" class=val>21.99
... </td>
... """)
>>> for key in bs.findAll(attrs={"class": "key"}):
...     value = key.findNext(attrs={"class": "val"})
...     print key.string.strip(), "-->", value.string.strip()
...
Open: --> 5.50
Mkt Cap: --> 6.92M
P/E: --> 21.99




From clp2 at rebertia.com  Thu Jul  9 03:29:33 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 00:29:33 -0700
Subject: i need immediate help from u
In-Reply-To: <a97ce0940907090025v7734dd5braa035ecbe92633f6@mail.gmail.com>
References: <a97ce0940907090025v7734dd5braa035ecbe92633f6@mail.gmail.com>
Message-ID: <50697b2c0907090029n66002f7cy68a5c51082c2b232@mail.gmail.com>

On Thu, Jul 9, 2009 at 12:25 AM, m.reddy prasad
reddy<reddy.mrp at gmail.com> wrote:
> i m new this community .;
> can any one send me the solution for writing the assembly language programs
> in python
> my mail ID:redd.mrp at gmail.com

Please read http://catb.org/esr/faqs/smart-questions.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From CHausberger at gmx.de  Thu Jul  9 03:41:20 2009
From: CHausberger at gmx.de (Claus Hausberger)
Date: Thu, 09 Jul 2009 09:41:20 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <4A53B2B4.9090409@mrabarnett.plus.com>
References: <20090707135949.100950@gmx.net> <4A53643C.4020905@xs4all.nl>
	<20090707190046.152740@gmx.net> <4A53B2B4.9090409@mrabarnett.plus.com>
Message-ID: <20090709074120.198030@gmx.net>

Thanks a lot. I will try that on the weekend.

Claus

> Claus Hausberger wrote:
> > Thanks a lot. Now I am one step further but I get another strange error:
> > 
> > Traceback (most recent call last):
> >   File "./read.py", line 12, in <module>
> >     of.write(text)
> > UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in
> position 0: ordinal not in range(128)
> > 
> > according to google ufeff has something to do with byte order.
> > 
> > I use an Linux system, maybe this helps to find the error.
> > 
> 'text' contains Unicode, but you're writing it to a file that's not
> opened for Unicode. Either open the output file for Unicode:
> 
>      of = codecs.open("umlaut-out.txt", "w", encoding="latin1")
> 
> or encode the text before writing:
> 
>      text = text.encode("latin1")
> 
> (I'm assuming you want the output file to be in Latin1.)
> 
> > 
> >> Claus Hausberger wrote:
> >>
> >>> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
> >>> change that as I do not create those files myself. I have to read
> >>> those files and convert the umlauts like ? to stuff like &oumol; as
> >>> the text files should become html files.
> >> umlaut-in.txt:
> >> ----
> >> This file is contains data in the unicode
> >> character set and is encoded with utf-8.
> >> Viele R?hre. Macht spa?!  Ts?sch!
> >>
> >>
> >> umlaut-in.txt hexdump:
> >> ----
> >> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is
> con
> >> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in
> th
> >> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e
> unicode..chara
> >> 000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and
> is
> >> 000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with
> utf
> >> 000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele
> R..hr
> >> 000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht
> spa..!
> >> 000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00 
> Ts..sch!.......
> >>
> >>
> >> umlaut.py:
> >> ----
> >> # -*- coding: utf-8 -*-
> >> import codecs
> >> text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
> >> text=text.replace(u"?",u"oe")
> >> text=text.replace(u"?",u"ss")
> >> text=text.replace(u"?",u"ue")
> >> of=open("umlaut-out.txt","w")
> >> of.write(text)
> >> of.close()
> >>
> >>
> >> umlaut-out.txt:
> >> ----
> >> This file is contains data in the unicode
> >> character set and is encoded with utf-8.
> >> Viele Roehre. Macht spass!  Tsuesch!
> >>
> >>
> >> umlaut-out.txt hexdump:
> >> ----
> >> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is
> con
> >> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in
> th
> >> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e
> unicode...char
> >> 000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and
> is
> >> 000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with
> ut
> >> 000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele
> Roe
> >> 000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht
> spass
> >> 000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 ! 
> Tsuesch!.....
> >>
> >>
> >>
> >>
> >>
> >> -- 
> >> "The ability of the OSS process to collect and harness
> >> the collective IQ of thousands of individuals across
> >> the Internet is simply amazing." - Vinod Valloppillil
> >> http://www.catb.org/~esr/halloween/halloween4.html
> > 
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list

-- 
Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
f?r nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


From rajat.dudeja at gmail.com  Thu Jul  9 03:55:37 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Thu, 9 Jul 2009 00:55:37 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz> 
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com> 
	<mailman.2827.1247039136.8015.python-list@python.org>
Message-ID: <a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>

On Jul 8, 12:45?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Rajat wrote:
> > On Jul 8, 4:57 am, Lawrence D'Oliveiro <l... at geek-
> > central.gen.new_zealand> wrote:
> >> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>
> >> Heimes wrote:
> >>> By the way most operating systems don't lock a file when it's opened for
> >>> reading or writing or even executed.
> >> The general conclusion seems to be that mandatory locking is more trouble
> >> than it's worth.
>
> > My OS is a windows XP sp3. All I'm trying to achieve is to close an
> > application ( which could be a notepad, a wordpad or some other text
> > editor) that have opened my file. Once the file is closed I can easily
> > delete that file.
>
> > I guess, if file is opened by one of that application, the file must
> > be locked and so is the reason I cannot delete the file.
>
> I assume that your real requirement is: I can't open/close/delete
> this file; it must be locked by something else; what is that
> something else?
>
> The simplest thing is probably to run sysinternals' handle util:
>
> ?http://technet.microsoft.com/en-us/sysinternals/bb896655.aspx
>
> and use the subprocess module to parse the output.
> That will give you the pid, and you can then use, eg, psutil:
>
> ?http://code.google.com/p/psutil/
>
> to get the details of the process.
>
> TJG- Hide quoted text -
>
> - Show quoted text -

I've used the Handle.exe and got the following results:

------------------------------------------------------------------------------
notepad.exe pid: 3540 COMP\rajatd
    C: File  (RW-)   C:\Documents and Settings\rajatd\Desktop
   10: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   44: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   7C: Section       \BaseNamedObjects\ShimSharedMemory

------------------------------------------------------------------------------
wordpad.exe pid: 2212 COMP\rajatd
   1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   74: Section       \BaseNamedObjects\ShimSharedMemory
   F8: Section       \BaseNamedObjects
\CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
  170: Section       \BaseNamedObjects\RotHintTable
  184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents

I've also parsed this output for the PIDS. But no where in the result
I got to know what file has been associated with a PID.

Does for this I need to use pustil?


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 03:57:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 04:57:15 -0300
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
Message-ID: <op.uwsi1pv3x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 23:19:25 -0300, kj <no.email at please.post> escribi?:

> In <mailman.2700.1246895025.8015.python-list at python.org> Tim Rowe  
> <digitig at gmail.com> writes:
>
>> 2009/7/4 kj <no.email at please.post>:
>
>>> Precisely. =A0As I've stated elsewhere, this is an internal helper
>>> function, to be called only a few times under very well-specified
>>> conditions. =A0The assert statements checks that these conditions
>>> are as intended. =A0I.e. they are checks against the module writer's
>>> programming errors.
>
>> Good for you. I'm convinced that you have used the assertion
>> appropriately, and the fact that so many here are unable to see that
>> looks to me like a good case for teaching the right use of assertions.
>> For what it's worth, I read assertions at the beginning of a procedure
>> as part of the specification of the procedure, and I use them there in
>> order to document the procedure. An assertion in that position is for
>> me a statement to the user of the procedure "it's your responsibility
>> to make sure that you never call this procedure in such a way as to
>> violate these conditions". They're part of a contract, as somebody
>> (maybe you) pointed out.
>
>> As somebody who works in the safety-critical domain, it's refreshing
>> to see somebody teaching students to think about the circumstances in
>> which a procedure can legitimately be called. The hostility you've
>> received to that idea is saddening, and indicative of why there's so
>> much buggy software out there.
>
> Thanks for the encouragement.
>
> When I teach programming, the students are scientists.  For the
> stuff they do, correctness of the code trumps everything else.  I
> teach them to view assertions as way of translating their assumptions
> into code.  And by this I mean not only assumptions about the
> correctness of their code (the typical scope of assertions), but
> also, more broadly, assumptions about the data that they are dealing
> with (which often comes from external sources with abysmal quality
> control).

Nobody says you shouldn't check your data. Only that "assert" is not the  
right way to do that. Ok, it's easier to write:

   assert x>0 and y>0 and x<y

instead of:

   if not (x>0 and y>0 and x<y):
     raise ValueError, "x=%r y=%r" % (x,y)

but the assert statement is completely ignored if your script is run with  
the -O option, and then no check is done.
assert should be used only to verify internal correctness only - to detect  
wrong assumptions in the *code* itself. Once you're confident the code is  
OK, you may turn off assertions (and improve program speed). But you must  
*always* validate input data no matter what - so assert is not the right  
tool.

Even worse, never DO anything inside an assertion - it won't be done in  
the optimized version. This method becomes almost empty when assertions  
are removed (not the intended behavior!):

def process_all(self):
     for item in self.items:
       assert self.process(item)

> My scientific code is jam-packed with assertions.  I can't count
> the number of times that one such lowly assertion saved me from a
> silent but potentially disastrous bug.  And yes I find it distressing
> that so so few programmers in my line of work use assertions at
> all.

I'm just saying that some of those assertions probably should be real "if  
... raise" statements instead - not that you remove the checks. You may  
use this short function, if you prefer:

def fassert(condition, message='', exc_type=AssertionError):
   if not condition:
     raise exc_type(message)

-- 
Gabriel Genellina



From __peter__ at web.de  Thu Jul  9 03:59:54 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 09 Jul 2009 09:59:54 +0200
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
Message-ID: <h3481q$d95$00$1@news.t-online.com>

Paul Simon wrote:

> "Chris Rebert" <clp2 at rebertia.com> wrote in message
> news:mailman.2863.1247095339.8015.python-list at python.org...
> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>> I have the "tkinter" problem and need some assistance to straighten it
>> out.
>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>> >"step
>> 1" and cannot import "_tkinter." I do not have that file on my computer,
>> but
>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>> This python stuff is great, but the documentation frequently
>> feels like it is just a bit out of my grasp. I realize that all of this
>> is free but I understand the instructions on the web page to repair only
>> to the
>> point of confusion. I'm not an expert. How do I modify my python
>> configuration? Is there a file that needs to be edited? Which setup.py
>> file
>> do I use? Make? or python setup.py build and python setup.py install?
>> Thanks. I appreciate your help.
> 
> - How did you install Python?
> - What Linux distro are you using?
> 
> Cheers,
> Chris
> http://blog.rebertia.com
> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
> exactly how I installed Python.  Originally I had installed 2.5 from RPM
> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
> something from python.org and installed.  Not sure if it was tarball or
> zip file.

Zip or tar doesn't matter, you are installing "from source".

Python has to find the necessary include files for tcl/tk. These are in 
separate packages that you have to install before you invoke Python's 
configure script.

I don't know what they are called on your system -- look for tk-dev.rpm, 
tcl-dev.rpm or similar.

You may run into the same problem with other modules like readline.

Peter



From mukherjee.tanmoy at gmail.com  Thu Jul  9 04:18:30 2009
From: mukherjee.tanmoy at gmail.com (Tanmoy)
Date: Thu, 9 Jul 2009 13:48:30 +0530
Subject: Hello
Message-ID: <c140049d0907090118v1307828dmfbe42bd2bc113050@mail.gmail.com>

Hi ...
    I have been trying to set this 2-D array of this sort.

  0 10 20 ........... 1000
  1 11 21...............

   1000


Here is the code i tried ...

arr=[]
for i in range(0,1010,10):
    arr.append([])
    for j in range(0,1001,1):
          arr[i].append(i+j)

print arr

I am getting the following error
 list index out of range

Please let me know where am i getting wrong.

Sincerely
tank
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/ae1f5689/attachment.html>

From gagsl-py2 at yahoo.com.ar  Thu Jul  9 04:19:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 05:19:37 -0300
Subject: Problem with list of dicts and copying
References: <5700df6b0907081009p5ec4167cqec36e915e0f6c4@mail.gmail.com>
Message-ID: <op.uwsj2zqex6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 14:09:43 -0300, Cameron Pulsford  
<cameron.pulsford at gmail.com> escribi?:

> I'm representing the board as a dictionary, where the keys are
> (x, y) positions, and the values are candidates. So my program goes along
> picking numbers from the list of candidates and then propagating the
> constraints. [...]Basically my boards list should be copies of good  
> boards, and when I need to
> refresh the current board, I want to pull off a copy of the correct one. 
> [...] this isn't happening. I am always modifying the same board.

You have a dictionary whose values are lists, ok? The copy() method  
doesn't make a copy of those lists - only of the dictionary itself. Try  
using the deepcopy function in the copy module:
http://docs.python.org/library/copy.html

-- 
Gabriel Genellina



From mail at timgolden.me.uk  Thu Jul  9 04:21:17 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 09 Jul 2009 09:21:17 +0100
Subject: Check file is locked?
In-Reply-To: <a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
Message-ID: <4A55A87D.6060802@timgolden.me.uk>

Rajat wrote:
> I've used the Handle.exe and got the following results:
> 
> ------------------------------------------------------------------------------
> notepad.exe pid: 3540 COMP\rajatd
>     C: File  (RW-)   C:\Documents and Settings\rajatd\Desktop
>    10: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    44: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    7C: Section       \BaseNamedObjects\ShimSharedMemory
> 
> ------------------------------------------------------------------------------
> wordpad.exe pid: 2212 COMP\rajatd
>    1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    74: Section       \BaseNamedObjects\ShimSharedMemory
>    F8: Section       \BaseNamedObjects
> \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
>   170: Section       \BaseNamedObjects\RotHintTable
>   184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
> 
> I've also parsed this output for the PIDS. But no where in the result
> I got to know what file has been associated with a PID.
> 
> Does for this I need to use pustil?


Well unless I'm missing your point considerably, the output tells
you all you need to know: notepad.exe (pid 3540) has some kind
of handle open on the desktop, the common controls DLL and an
area of shared memory. As has been pointed out elsewhere, notepad
doesn't hold the file open which it's editing: it opens it, reads
the contents, and closes it again. 

For demonstration purposes:

<code>
import os, sys
import subprocess

f = open (sys.executable)
subprocess.call (["handle", sys.executable])
f.close ()

</code>


TJG


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 04:23:51 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 05:23:51 -0300
Subject: windows command-line
References: <376017.28322.qm@web30601.mail.mud.yahoo.com>
	<h32kne$s0l$1@ger.gmane.org>
Message-ID: <op.uwsj91v2x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 14:23:54 -0300, Emile van Sebille <emile at fenx.com>  
escribi?:
> On 7/8/2009 10:07 AM Lucas Junqueira said...

>> Hi, I'd like to run a simple windows command-line program from within  
>> my python script and agt all the returt it generates. Is this possible?  
>> How can I do it?
>
> Depending on python version, look into subprocess, commands or os.pipe  
> and related.

commands is Unix only, and os.pipe by itself doesn't solve the problem -  
so we are left with subprocess, and that would be my reccomendation too.

-- 
Gabriel Genellina



From dickinsm at gmail.com  Thu Jul  9 04:29:02 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Thu, 9 Jul 2009 01:29:02 -0700 (PDT)
Subject: python3 fail to start
References: <788ec223-9894-4168-b1f8-758cd51a47ad@r16g2000vbn.googlegroups.com>
Message-ID: <06650e06-5073-4420-972c-1add7c9bbbd6@h8g2000yqm.googlegroups.com>

On Jun 30, 3:43?pm, ts <thaisi... at gmail.com> wrote:
> i just install the python 3.1 dmg onto my mac. when i run python3, it
> fail with :
>
> Fatal Python error: Py_Initialize: can't initialize sys standard
> streamsLookupError: unknown encoding:
> Abort trap
>
> couldnt understand the problem. anyone can help?

Any chance you could give us some feedback about your system?  The
Python devs are working to fix the problem:

http://bugs.python.org/issue6393

but it would be really helpful to know:

- what version of OS X you're using
- what output you get when you type 'locale' at a Terminal prompt
- what the International settings are in your Terminal preferences
  (Terminal preferences -> Settings -> Advanced tab):  what's the
  setting for the character encoding, and do you have the 'Set LANG
  environment variable at startup' checkbox checked?

I managed to reproduce the crash by starting python3 (again
at a Terminal prompt) with:

LANG=UTF-8 python3

So I suspect that your locale settings are part of the problem.
As a temporary workaround, something like

LANG=en_US.UTF-8 python3

might work.  (Substitute whatever language setting is appropriate
for you in place of en_US.)

Thanks!

Mark


From python at mrabarnett.plus.com  Thu Jul  9 04:41:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 09 Jul 2009 09:41:42 +0100
Subject: Hello
In-Reply-To: <c140049d0907090118v1307828dmfbe42bd2bc113050@mail.gmail.com>
References: <c140049d0907090118v1307828dmfbe42bd2bc113050@mail.gmail.com>
Message-ID: <4A55AD46.8010407@mrabarnett.plus.com>

Tanmoy wrote:
T Hi ...
>     I have been trying to set this 2-D array of this sort.
> 
>   0 10 20 ........... 1000
>   1 11 21...............
>   
>    1000
> 
> 
> Here is the code i tried ...
> 
> arr=[]
> for i in range(0,1010,10):
>     arr.append([])
>     for j in range(0,1001,1):
>           arr[i].append(i+j)
>          
> print arr
> 
> I am getting the following error
>  list index out of range
> 
> Please let me know where am i getting wrong.
> 
The value of 'i' goes 0, 10, ..., etc.

When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
problem.

When i==10 you append another empty list to arr, so arr[i] is arr[10].
Index error because there's no arr[10], only arr[0] and arr[1].


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 05:03:21 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 06:03:21 -0300
Subject: can i write a assemly language programs in python
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <op.uwsl3vobx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 09 Jul 2009 04:17:52 -0300, m.reddy prasad reddy  
<reddy.mrp at gmail.com> escribi?:

> can any one tell me how to write assembly language programs in  
> python...if
> no is there any other way to write the programs in python

You write Python programs using Python, not assembly.

Perhaps if you provide more info on what you want to do, someone can  
suggest a different way...

-- 
Gabriel Genellina



From andy2.0 at gmail.com  Thu Jul  9 05:26:10 2009
From: andy2.0 at gmail.com (Andy Clegg)
Date: Thu, 9 Jul 2009 02:26:10 -0700 (PDT)
Subject: subprocess + python-daemon - bug/problem?
Message-ID: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>

Hi all,

I'm trying to daemonize a python program, and occasionally have it run
subprocesses, however I'm running into a nasty error, as follows:

"File "/users/rsg/ancl/devcocast/devcocast-svn/scripts/DaemonSpawnTes
t.py", line 5, in <module>
    subprocess.Popen('echo 1').wait()
  File "/usr/lib64/python2.5/subprocess.py", line 594, in __init__
    errread, errwrite)
  File "/usr/lib64/python2.5/subprocess.py", line 1089, in _execute_ch
ild
    os.waitpid(self.pid, 0)
OSError: [Errno 10] No child processes"

The minimal testcase showing this problem is as follows:

"import daemon
import subprocess

daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
subprocess.Popen('echo 1').wait()"

So there is no threading going on (I've found some bugs relating to
subprocess and threading). I'm using Fedora 10, Python 2.5.2, and
python-daemon 1.4.6 from here http://pypi.python.org/pypi/python-daemon/
.

If anyone can shed some light on the situation, I'd be extremely
grateful!

Yours,

Andy


From user at example.net  Thu Jul  9 05:36:13 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 11:36:13 +0200
Subject: older pythons
Message-ID: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>

hi everybody.

i have a certain set of old python scripts and data used by said scripts 
which were written using python 2.3

in particular i used some features which were later modified or 
deprecated by the language newer versions (e.g.: cmp(), print as 
keyword, and such...)

for reasons i find hard to explain briefly, it is unfeasible at the 
moment to modify scripts and data to adapt to the changes

now: i ask if it is possible to have different versions of python 
installed on my system (linux debian) so that i can continue to use 
python 2.3 (as "python" from the shell) but i can also use - say - 
python 3.1 (maybe as "python3.1" from the shell)

if yes: is there a known recommended way to do so?

thanks a lot

bye


From andy2.0 at gmail.com  Thu Jul  9 05:42:54 2009
From: andy2.0 at gmail.com (Andy Clegg)
Date: Thu, 9 Jul 2009 02:42:54 -0700 (PDT)
Subject: subprocess + python-daemon - bug/problem?
References: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>
Message-ID: <828acd8d-a9bd-4506-b695-e537af4587d8@l31g2000yqb.googlegroups.com>

My apologies, the python code should have been:

"import daemon
import subprocess

daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
subprocess.Popen(['echo','1']).wait()"

However the error remains the same.

Yours,

Andy

On Jul 9, 10:26?am, Andy  Clegg <andy... at gmail.com> wrote:
> Hi all,
>
> I'm trying to daemonize a python program, and occasionally have it run
> subprocesses, however I'm running into a nasty error, as follows:
>
> "File "/users/rsg/ancl/devcocast/devcocast-svn/scripts/DaemonSpawnTes
> t.py", line 5, in <module>
> ? ? subprocess.Popen('echo 1').wait()
> ? File "/usr/lib64/python2.5/subprocess.py", line 594, in __init__
> ? ? errread, errwrite)
> ? File "/usr/lib64/python2.5/subprocess.py", line 1089, in _execute_ch
> ild
> ? ? os.waitpid(self.pid, 0)
> OSError: [Errno 10] No child processes"
>
> The minimal testcase showing this problem is as follows:
>
> "import daemon
> import subprocess
>
> daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
> subprocess.Popen('echo 1').wait()"
>
> So there is no threading going on (I've found some bugs relating to
> subprocess and threading). I'm using Fedora 10, Python 2.5.2, and
> python-daemon 1.4.6 from herehttp://pypi.python.org/pypi/python-daemon/
> .
>
> If anyone can shed some light on the situation, I'd be extremely
> grateful!
>
> Yours,
>
> Andy



From adrian.dziubek at gmail.com  Thu Jul  9 05:53:40 2009
From: adrian.dziubek at gmail.com (Adrian Dziubek)
Date: Thu, 9 Jul 2009 02:53:40 -0700 (PDT)
Subject: older pythons
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
Message-ID: <d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>

The recommended Debian way is update-alternatives. I find it a bit
unintuitive, so I have to read through the documentation every time I
use it, but it should be able link a chosen version of python to /usr/
bin/python. I don't know if it's set up by default, I have only one
version installed.
--
Adrian


From rajat.dudeja at gmail.com  Thu Jul  9 06:03:00 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Thu, 9 Jul 2009 03:03:00 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz> 
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com> 
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
Message-ID: <a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>

On Jul 9, 1:21?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Rajat wrote:
> > I've used the Handle.exe and got the following results:
>
> > ---------------------------------------------------------------------------?---
> > notepad.exe pid: 3540 COMP\rajatd
> > ? ? C: File ?(RW-) ? C:\Documents and Settings\rajatd\Desktop
> > ? ?10: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?44: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?7C: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
>
> > ---------------------------------------------------------------------------?---
> > wordpad.exe pid: 2212 COMP\rajatd
> > ? ?1C: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?40: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?74: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
> > ? ?F8: Section ? ? ? \BaseNamedObjects
> > \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
> > ? 170: Section ? ? ? \BaseNamedObjects\RotHintTable
> > ? 184: File ?(RW-) ? C:\Documents and Settings\rajatd\My Documents
>
> > I've also parsed this output for the PIDS. But no where in the result
> > I got to know what file has been associated with a PID.
>
> > Does for this I need to use pustil?
>
> Well unless I'm missing your point considerably, the output tells
> you all you need to know: notepad.exe (pid 3540) has some kind
> of handle open on the desktop, the common controls DLL and an
> area of shared memory. As has been pointed out elsewhere, notepad
> doesn't hold the file open which it's editing: it opens it, reads
> the contents, and closes it again.
>
> For demonstration purposes:
>
> <code>
> import os, sys
> import subprocess
>
> f = open (sys.executable)
> subprocess.call (["handle", sys.executable])
> f.close ()
>
> </code>
>
> TJG- Hide quoted text -
>
> - Show quoted text -

The Notepad process information is fine here. However, with wordpad
the results are not much differentiating:

------------------------------------------------------------------------------
wordpad.exe pid: 2832 COMP\rajatd
   1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   74: Section       \BaseNamedObjects\ShimSharedMemory
   F8: Section       \BaseNamedObjects
\CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
  170: Section       \BaseNamedObjects\RotHintTable
  184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
------------------------------------------------------------------------------
wordpad.exe pid: 844 COMP\rajatd
   1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   74: Section       \BaseNamedObjects\ShimSharedMemory
   F8: Section       \BaseNamedObjects
\CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
  170: Section       \BaseNamedObjects\RotHintTable
  184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents

Both the wordpad applications opened 2 totally different files kept at
different locations on the system.

So, on the basis of above results one can not say out of these 2
wordpad apps which is the right one that could be closed. The only
different thing among the two is the PIDs.


From luislupeXXX at gmailXXX.com  Thu Jul  9 06:06:16 2009
From: luislupeXXX at gmailXXX.com (Luis P. Mendes)
Date: 09 Jul 2009 10:06:16 GMT
Subject: Psyco 64 bits
Message-ID: <4a55c118$0$48237$14726298@news.sunsite.dk>

Hi,

I used Psyco to speed up my Python code.
Due to the great amount of data I have to proccess, I moved my Linux 
system to a 64 bits version with more RAM.

It seems that Psyco cannot be used in such platforms.
Or is there another version of Psyco for 64 bits platform?

I googled and arrived to PyPy.  But I don't know how to use it.
With psyco, I used to include two statements roughly at the beginning of 
the script:
import psyco
psyco.full()

With PyPy, is there a similar way to try to speed up my script?


Luis


From tkermode at gmail.com  Thu Jul  9 06:13:43 2009
From: tkermode at gmail.com (Tom Kermode)
Date: Thu, 9 Jul 2009 11:13:43 +0100
Subject: can i write a assemly language programs in python
In-Reply-To: <op.uwsl3vobx6zn5v@lepton.softlabbsas.com.ar>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
	<op.uwsl3vobx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <da7092380907090313v10d72af9k5dbfbb9507129eb5@mail.gmail.com>

I wonder if the OP is trying to find out whether python programmes can
be compiled and run as stand alone executables.

(I know assembly and machine code are not the same, but it might be
what they're after.)

On windows you can use http://www.py2exe.org/ to bundle python
programs into stand alone executables. They're not compiled, but your
code and all the modules it relies on are brought together, meaning
you can deliver a single exe than can be run like any other windows
program.

Maybe that helps...

2009/7/9 Gabriel Genellina <gagsl-py2 at yahoo.com.ar>:
> En Thu, 09 Jul 2009 04:17:52 -0300, m.reddy prasad reddy
> <reddy.mrp at gmail.com> escribi?:
>
>> can any one tell me how to write assembly language programs in python...if
>> no is there any other way to write the programs in python
>
> You write Python programs using Python, not assembly.
>
> Perhaps if you provide more info on what you want to do, someone can suggest
> a different way...
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.kiloday.com
http://www.fourstopspast.com


From mail at timgolden.me.uk  Thu Jul  9 06:21:51 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 09 Jul 2009 11:21:51 +0100
Subject: Check file is locked?
In-Reply-To: <a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
Message-ID: <4A55C4BF.6080200@timgolden.me.uk>

Rajat wrote:
> The Notepad process information is fine here. However, with wordpad
> the results are not much differentiating:
> 
> ------------------------------------------------------------------------------
> wordpad.exe pid: 2832 COMP\rajatd
>    1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    74: Section       \BaseNamedObjects\ShimSharedMemory
>    F8: Section       \BaseNamedObjects
> \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
>   170: Section       \BaseNamedObjects\RotHintTable
>   184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
> ------------------------------------------------------------------------------
> wordpad.exe pid: 844 COMP\rajatd
>    1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    74: Section       \BaseNamedObjects\ShimSharedMemory
>    F8: Section       \BaseNamedObjects
> \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
>   170: Section       \BaseNamedObjects\RotHintTable
>   184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
> 
> Both the wordpad applications opened 2 totally different files kept at
> different locations on the system.
> 
> So, on the basis of above results one can not say out of these 2
> wordpad apps which is the right one that could be closed. The only
> different thing among the two is the PIDs.


Rajat: are you trying to find out which app is holding a file open?

If so -- run handle.exe *for that filename*, as my code does:

handle.exe <filename>

This will only show which apps are holding that file. I suspect
you're running handle.exe on its own which will show everything
which is holding handles on anything.

1) Use wordpad.exe to open c:\temp\blah.txt

2) Run "handle.exe c:\temp\blah.txt"

3) Observe (at least on my Win XP Sp3 machine) that *no* process
has a handle open on c:\temp\blah.txt, including wordpad, which
presumably opens the file, reads it, and closes it again.


The items you're seeing above are system-level handles which
wordpad is holding for reasons of its own, but none of them
is a user filename.

TJG


From mukherjee.tanmoy at gmail.com  Thu Jul  9 06:31:56 2009
From: mukherjee.tanmoy at gmail.com (Tanmoy)
Date: Thu, 9 Jul 2009 16:01:56 +0530
Subject: Python-list Digest, Vol 70, Issue 123
In-Reply-To: <mailman.10425.1247132403.8014.python-list@python.org>
References: <mailman.10425.1247132403.8014.python-list@python.org>
Message-ID: <c140049d0907090331s3e15f277hfc701928ab2419e7@mail.gmail.com>

Hello ,
          When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
problem.

When i==10 you append another empty list to arr, so arr[i] is arr[10].
Index error because there's no arr[10], only arr[0] and arr[1].


Thanks for your prompt reply...

How can i pass this problem


Sincerely
Tanmoy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/e442d413/attachment.html>

From python at mrabarnett.plus.com  Thu Jul  9 06:39:34 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 09 Jul 2009 11:39:34 +0100
Subject: Python-list Digest, Vol 70, Issue 123
In-Reply-To: <c140049d0907090331s3e15f277hfc701928ab2419e7@mail.gmail.com>
References: <mailman.10425.1247132403.8014.python-list@python.org>
	<c140049d0907090331s3e15f277hfc701928ab2419e7@mail.gmail.com>
Message-ID: <4A55C8E6.3040803@mrabarnett.plus.com>

Tanmoy wrote:
> Hello ,
>           When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
> problem.
> 
> When i==10 you append another empty list to arr, so arr[i] is arr[10].
> Index error because there's no arr[10], only arr[0] and arr[1].
>  
> 
> Thanks for your prompt reply...
> 
> How can i pass this problem
> 
You could try appending to arr[-1] instead.

Better still:

     ...
     row = []
     for j in range(0,1001,1):
           row.append(i+j)
     arr.append(row)
     ...


From piet at cs.uu.nl  Thu Jul  9 06:43:43 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 09 Jul 2009 12:43:43 +0200
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
	<cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>
Message-ID: <m2fxd69lwg.fsf@cs.uu.nl>

>>>>> Fred Atkinson <fatkinson at mishmash.com> (FA) wrote:

>FA> On Wed, 08 Jul 2009 12:29:54 +0200, Piet van Oostrum <piet at cs.uu.nl>
>FA> wrote:

>>> Something like:
>>> 
>>> #! /usr/bin/env python
>>> 
>>> import cgi
>>> from os import getenv
>>> 
>>> print "Content-type: text/html"
>>> print
>>> 
>>> ipaddr = (getenv("HTTP_CLIENT_IP") or
>>> getenv("HTTP_X_FORWARDED_FOR") or
>>> getenv("HTTP_X_FORWARDED_FOR") or
>>> getenv("REMOTE_ADDR") or
>>> "UNKNOWN")
>>> 
>>> print ipaddr

>FA> That did it.  

>FA> I wonder why they don't just have a function to return it instead of
>FA> putting you through all of that?  

I see now that I had       getenv("HTTP_X_FORWARDED_FOR") or
duplicated.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From user at example.net  Thu Jul  9 06:49:59 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 12:49:59 +0200
Subject: older pythons
In-Reply-To: <d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
Message-ID: <4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>

Adrian Dziubek wrote:
> The recommended Debian way is update-alternatives. I find it a bit
> unintuitive, so I have to read through the documentation every time I
> use it, but it should be able link a chosen version of python to /usr/
> bin/python. I don't know if it's set up by default, I have only one
> version installed.
> --
> Adrian

what i was asking for is about a way to *INSTALL* and mantain different 
python versions, a task i think is not unusal for developers.

thanks anyway for reply

bye


From reddy.mrp at gmail.com  Thu Jul  9 06:52:44 2009
From: reddy.mrp at gmail.com (m.reddy prasad reddy)
Date: Thu, 9 Jul 2009 16:22:44 +0530
Subject: need to write a assembly progrm
Message-ID: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>

my aim is to run the assembly programs in python.by that we can use that in
the any labs.because we can run the python in the mobiles also.if we write
assembly programs in the mobile ,the mobile act as a tool kit for the
lab.tell me any other solutions for this
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/18f4b7b3/attachment.html>

From rajat.dudeja at gmail.com  Thu Jul  9 06:53:29 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Thu, 9 Jul 2009 03:53:29 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz> 
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com> 
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
	<mailman.2880.1247134886.8015.python-list@python.org>
Message-ID: <652cca82-44a3-473f-b640-c2336a9cf929@v15g2000prn.googlegroups.com>

On Jul 9, 3:21?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Rajat wrote:
> > The Notepad process information is fine here. However, with wordpad
> > the results are not much differentiating:
>
> > ---------------------------------------------------------------------------?---
> > wordpad.exe pid: 2832 COMP\rajatd
> > ? ?1C: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?40: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?74: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
> > ? ?F8: Section ? ? ? \BaseNamedObjects
> > \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
> > ? 170: Section ? ? ? \BaseNamedObjects\RotHintTable
> > ? 184: File ?(RW-) ? C:\Documents and Settings\rajatd\My Documents
> > ---------------------------------------------------------------------------?---
> > wordpad.exe pid: 844 COMP\rajatd
> > ? ?1C: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?40: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?74: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
> > ? ?F8: Section ? ? ? \BaseNamedObjects
> > \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
> > ? 170: Section ? ? ? \BaseNamedObjects\RotHintTable
> > ? 184: File ?(RW-) ? C:\Documents and Settings\rajatd\My Documents
>
> > Both the wordpad applications opened 2 totally different files kept at
> > different locations on the system.
>
> > So, on the basis of above results one can not say out of these 2
> > wordpad apps which is the right one that could be closed. The only
> > different thing among the two is the PIDs.
>
> Rajat: are you trying to find out which app is holding a file open?
>
> If so -- run handle.exe *for that filename*, as my code does:
>
> handle.exe <filename>
>
> This will only show which apps are holding that file. I suspect
> you're running handle.exe on its own which will show everything
> which is holding handles on anything.
>
> 1) Use wordpad.exe to open c:\temp\blah.txt
>
> 2) Run "handle.exe c:\temp\blah.txt"
>
> 3) Observe (at least on my Win XP Sp3 machine) that *no* process
> has a handle open on c:\temp\blah.txt, including wordpad, which
> presumably opens the file, reads it, and closes it again.
>
> The items you're seeing above are system-level handles which
> wordpad is holding for reasons of its own, but none of them
> is a user filename.
>
> TJG- Hide quoted text -
>
> - Show quoted text -

Thanks Tim for the details. Just further on this, my whole idea is to
close the wordpad / notepad application so that I can delete the file
and the directory where this file resides.

With notepad it is no more a problem. But I'm concerned about the
wordpad now.


From manu3d at gmail.com  Thu Jul  9 06:59:45 2009
From: manu3d at gmail.com (Emanuele D'Arrigo)
Date: Thu, 9 Jul 2009 03:59:45 -0700 (PDT)
Subject: property using a classmethod
Message-ID: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>

Greetings,

today I did something like this:

class MyClass(object):

    @classmethod
    def myClassMethod(self):
         print "ham"

     myProperty = property(myClassMethod, None, None)

As many of you know this doesn't work and returns a TypeError: the
object passed to the property is not a callable function but a
classmethod object, which isn't callable at all. So, how do I do this?
Ultimately all I want is a non-callable class-level attribute
MyClass.myProperty that gives the result of MyClass.myClassMethod().

Can it be done?

Manu


From bearophileHUGS at lycos.com  Thu Jul  9 07:04:10 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 9 Jul 2009 04:04:10 -0700 (PDT)
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com> 
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com> <7xbpnuzw4u.fsf@ruckus.brouhaha.com> 
	<mailman.2865.1247105487.8015.python-list@python.org>
Message-ID: <e4a20167-4c63-4ab3-baf2-be1f41c81fd8@a36g2000yqc.googlegroups.com>

Paul Rubin:
> print x, sum(1 for _ in g)

Don't use that, use my function :-) If g has a __len__ you are wasting
time. And sum(1 ...) is (on my PC) slower.


J. Clifford Dyer:
> if __name__ == '__main__':
> ? ? test_func(summer, 10000000)
> ? ? test_func(tupler, 10000000)
> ? ? test_func(summer, 100000000)
> ? ? test_func(tupler, 100000000)

Have you forgotten my function?

Bye,
bearophile


From larrykavanagh at examiner.ie  Thu Jul  9 07:05:46 2009
From: larrykavanagh at examiner.ie (Larry kavanagh)
Date: Thu, 09 Jul 2009 12:05:46 +0100
Subject: python-ldap
Message-ID: <4A55CF0A.50707@examiner.ie>

Hi,
I need a PYTHON-LDAP package.

I'm trying to install ploneldap and it tells me I need python-ldap 
package first  .. but I can't find one to match my versions.

I'm using plone 3.2.2, Python 2.4.4 and Zope 2.10.7 on a Win32 environment.

Preferable I'd like an EXE as not too familiar with whole plone 
configuration.

The ones I've tried have all told me I need Python 2.4 installed and it 
can't find in the registry. My plone site tells me I'm python 2.4.4 so 
maybe I just need to configure some environment variables or PATHs or 
something prior to running an install ??

Can anyone help me
Thanks
Larry



Please consider the environment before printing this email.

Examiner Publications (Cork) Ltd
Directors:  G. A. Crosbie (Chairman), Thomas J. Murphy (Chief Executive), A.W. Dinan (Secretary), T.P. Crosbie. 
Registered In Dublin, Ireland. Registered number: 73385. Registered Office: City Quarter, Lapps Quay, Cork.





From bearophileHUGS at lycos.com  Thu Jul  9 07:10:53 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 9 Jul 2009 04:10:53 -0700 (PDT)
Subject: Psyco 64 bits
References: <4a55c118$0$48237$14726298@news.sunsite.dk>
Message-ID: <51ae217e-729d-4eac-957e-b01f054e4057@t13g2000yqt.googlegroups.com>

Luis P. Mendes:
> It seems that Psyco cannot be used in such platforms.
> Or is there another version of Psyco for 64 bits platform?
> I googled and arrived to PyPy. ?But I don't know how to use it.

Psyco will be updated, but probably not for 64 bit CPUs. At the moment
PyPy doesn't give you much speed up.
So you can try IronPython, but I don't think it will help. There's
also the Boo language, that's often fast enough.

If your code has few hot spots, then there are many solutions that can
be used. For example Cython, Weave, ShedSkin. Or writing external code
in C/C++/D/Fortran and interfacing with it with a plethora of means,
like ctypes, swig, PIL, Pyd, Boost.Python, Inline, and many other.
Running speed is a big problem in many Python programs, so they have
invented an army of possible solutions.

Bye,
bearophile


From lie.1296 at gmail.com  Thu Jul  9 07:15:45 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 11:15:45 GMT
Subject: older pythons
In-Reply-To: <4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
Message-ID: <Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>

superpollo wrote:
> Adrian Dziubek wrote:
>> The recommended Debian way is update-alternatives. I find it a bit
>> unintuitive, so I have to read through the documentation every time I
>> use it, but it should be able link a chosen version of python to /usr/
>> bin/python. I don't know if it's set up by default, I have only one
>> version installed.
>> -- 
>> Adrian
> 
> what i was asking for is about a way to *INSTALL* and mantain different
> python versions, a task i think is not unusal for developers.
> 
> thanks anyway for reply
> 
> bye

Installing several minor versions (e.g. 2.3, 2.4, 2.5, 3.0) in parallel
has always been supported. Just install them and it should work
"automagically".

However changing the system's default /usr/bin/python is NOT
recommended, especially in linux systems that rely heavily on python for
many of the system tools. If you install from source, you need to check
for some settings to ensure the installer does not install the
/usr/bin/python's symlink. If you install from a package manager, they
usually doesn't change the symlink and you'll need to run a separate
program to change the symlinks (e.g. python-updater in Gentoo, which
will also updates all installed python packages to the appropriate
version. Neat.).

The easiest way to make a specific script use a specific version of
python is by changing its hashbang (#!) line:

instead of:
#!/usr/bin/env python

use
#!/usr/bin/env python2.3

or whatever version it should run on.

AFAIK, no major linux distributions have officially ported to python
3.x. This means switching /usr/bin/python to python3.1 will definitely
break your system. As an alternative, you can always explicitly specify
the version number of python you want to use:

$ python2.5
Python 2.5.4 (r254:67916, Jul  5 2009, 04:12:16)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
$ python2.6
Python 2.6.2 (r262:71600, Jul  5 2009, 04:08:11)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
$ python3.0
Python 3.0.1 (r301:69556, Jul  5 2009, 04:03:20)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
$ python3.0 need3.py
happily running with python 3.0
$ python2 need3.py
SillyError: not running with python 3.0


From piet at cs.uu.nl  Thu Jul  9 07:31:44 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 09 Jul 2009 13:31:44 +0200
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
Message-ID: <m27hyi9jof.fsf@cs.uu.nl>

>>>>> Lacrima <Lacrima.Maxim at gmail.com> (L) wrote:

>L> Thanks for your reply!
>L> My file name is 'trains.py'.
>L> When I do C-h k C-c RET, it shows me help from manual: "C-c RET runs
>L> the command py-execute-import-or-reload
>L>    which is an interactive Lisp function in `python-mode'..." and so
>L> on.

>L> And still when I do C-c RET, I receive "(Shell command succeeded with
>L> no output)"

>L> Any more help would be really appreciated, because I am newbie with
>L> Emacs.

I tested it and I can get this message also. It happens when you have no
Python shell running (*Python* buffer). The python code is then executed
by calling the python shell command and catching the output. This output
is displayed in the *Python Output* buffer. It happens also with C-c C-c
and it will give the same message.

There is a difference, however between C-c C-x and C-c RET: The latter
will import your module, and most modules are written such that
importing them doesn't print anything. If you add something like 
print "test" and the end of file, then "test" will appear in the *Python
Output*  buffer.

If your file has the print "hello world" statement it should display in
the *Python Output* buffer. I checked that.

On the other hand, if you have a python shell running you must make sure
(e.g. with the cd command) that its working directory is the directory
where your python file is located, otherwise the import statement will
not find your file. Unless it is somewhere in the python path. Also the
*Python* buffer will not automatically pop up if it is not visible, in
contrast with the *Python Output* buffer.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From fabiofz at gmail.com  Thu Jul  9 07:35:32 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Thu, 9 Jul 2009 08:35:32 -0300
Subject: Pydev 1.4.7 Released
In-Reply-To: <7blh8oF2367ioU2@mid.individual.net>
References: <mailman.2861.1247094510.8015.python-list@python.org>
	<7blh8oF2367ioU2@mid.individual.net>
Message-ID: <cfb578b20907090435ob708c3ci38ed91e617506d58@mail.gmail.com>

Yes.

On Thu, Jul 9, 2009 at 3:32 AM, Morten Nygaard
Aasnes<morten.aasnes at gmail.com> wrote:
> On 2009-07-08, Fabio Zadrozny <fabiofz at gmail.com> wrote:
>> Hi All,
>>
>> Pydev and Pydev Extensions 1.4.7 have been released
>>
>> Details on Pydev Extensions: http://www.fabioz.com/pydev
>> Details on Pydev: http://pydev.sf.net
>> Details on its development: http://pydev.blogspot.com
>
> Nice! Will this work in Eclipse 3.5 as well?
>
> --
> Morten Nygaard ?snes ? http://twitter.com/mortenaa ? http://identi.ca/mortenaa
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From user at example.net  Thu Jul  9 07:39:37 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 13:39:37 +0200
Subject: older pythons
In-Reply-To: <Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
Message-ID: <4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>

Lie Ryan wrote:

> AFAIK, no major linux distributions have officially ported to python
> 3.x.

http://packages.debian.org/experimental/python3.1

thanks for help


From helvinlui at gmail.com  Thu Jul  9 07:42:37 2009
From: helvinlui at gmail.com (Helvin)
Date: Thu, 9 Jul 2009 04:42:37 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
Message-ID: <7a641820-7e7e-44a8-aae5-9cf9822aab6d@p36g2000prn.googlegroups.com>

On Jul 9, 6:27?pm, Helvin <helvin... at gmail.com> wrote:
> On Jul 9, 11:29?am, Robert Kern <robert.k... at gmail.com> wrote:
>
>
>
>
>
> > On 2009-07-08 18:10, Helvin wrote:
>
> > > Thanks for the fast replies! I will look into how to use VTK now.
> > > Where would I find VTK's explicit support for PyQt?
>
> > Wrapping/Python/vtk/qt4/ in the VTK sources.
>
> > > Because I have installed VTK (using its installer) and pyVTK (using
> > > its setup.py file), but how do I actually use it in my code? According
> > > to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
> > > I have tried 'import vtk', but python can't find the vtk module.
>
> > Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
> > just a library for manipulating VTK files. The VTK Python bindings are part of
> > VTK's distribution itself. Exactly how did you install VTK? Did you compile it
> > yourself?
>
> > --
> > Robert Kern
>
> > "I have come to believe that the whole world is an enigma, a harmless enigma
> > ? that is made terrible by our own mad attempt to interpret it as though it had
> > ? an underlying truth."
> > ? ?-- Umberto Eco
>
> You mean, when I download VTK, the VTK Python bindings come with it?
> I downloaded VTK from:http://vtk.org/files/release/5.4/
>
> I downloaded pyVTK from:http://pypi.python.org/pypi/PyVTK/0.4.67
> And then installed it by the command 'python setup.py install'
> according to:http://cens.ioc.ee/projects/pyvtk/
> I understand that this command runs the file called 'setup.py' that
> came with the pyVTK download.
>
> Thanks so much for your help! I am very desperate now...
>
> Helvin

I googled: vtk for beginners python.
>From there, I found this: http://www.nabble.com/pls-help-how-to-install-VTK-and-run-td14977428.html
And from there, this: http://www-viz.tamu.edu/courses/viza658/08spring/tutorials/WinVTKInstall.html

This last one has very detailed info about how to get started with
VTK. I am now redoing the installing VTK thing. Hope it will work.

Helvin


From mondi at cs.unibo.it  Thu Jul  9 07:50:20 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Thu, 09 Jul 2009 11:50:20 +0000
Subject: hoe to build a patched socketmodule.c
Message-ID: <h34dsu$a4j$1@lec.cs.unibo.it>

Hi all, I need to patch socketmodule.c (the _socket module) in order to
add support to an experimental socket family.

I'm guessing about the patched module build process: does a stand alone
build script using distutils makes sense, or have I to patch
sockmodule.c, eventualy rename it, modify setup.py inside python sources
to let it know about the new module, and then rebuild whole python?
I think the latter makes more sense, because I suppose socketmodule
could not be build stand alone, but need the whole python build system,
in order to have right definition specified by a Makefile generated by
autotools from inside python sources.
Or maybe distutils is able to retreive the whole build system? I don't
think so, because there are no requirement about having python source
tree installed.

If I have to go for the second way, then how could I distribuite the
patched _socket module? I could not use distutils, have I to distribuite
 the already built .so with only a script to install it, and the source
code in another directory?

Thanks a lot
	jacopo

PS correct my english please, is the only way I have to improve it!


From rashidsdpk at gmail.com  Thu Jul  9 07:59:28 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Thu, 9 Jul 2009 04:59:28 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <fc38a885-cf1a-4418-a82f-83f8d7c3c61e@37g2000yqp.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.
for more details on http://0nanotechnology0.blogspot.com


From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul  9 07:59:44 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 09 Jul 2009 13:59:44 +0200
Subject: property using a classmethod
In-Reply-To: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
Message-ID: <4a55db9e$0$10243$426a74cc@news.free.fr>

Emanuele D'Arrigo a ?crit :
> Greetings,
> 
> today I did something like this:
> 
> class MyClass(object):
> 
>     @classmethod
>     def myClassMethod(self):

<ot> Usually, the first argument of classmethods is named 'cls' </ot>

>          print "ham"
> 
>      myProperty = property(myClassMethod, None, None)
> 
> As many of you know this doesn't work and returns a TypeError: the
> object passed to the property is not a callable function but a
> classmethod object, which isn't callable at all.  So, how do I do this?
> Ultimately all I want is a non-callable class-level attribute
> MyClass.myProperty

properties *are* class attributes.

> that gives the result of MyClass.myClassMethod().
> 
> Can it be done?

You could write your own custom descriptor. Or just use an additional 
level of indirection, ie:

    myProperty = property(lambda self: self.myClassMethod())


but since you already have myClassMethod available, I don't see the 
point. What problem are you trying to solve exactly ?



From lie.1296 at gmail.com  Thu Jul  9 08:10:33 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 12:10:33 GMT
Subject: older pythons
In-Reply-To: <4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
Message-ID: <Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>

superpollo wrote:
> Lie Ryan wrote:
> 
>> AFAIK, no major linux distributions have officially ported to python
>> 3.x.
> 
> http://packages.debian.org/experimental/python3.1
> 
> thanks for help

Note the word "experimental"


From michael at stroeder.com  Thu Jul  9 08:17:49 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Thu, 09 Jul 2009 14:17:49 +0200
Subject: python-ldap
In-Reply-To: <mailman.2883.1247138347.8015.python-list@python.org>
References: <mailman.2883.1247138347.8015.python-list@python.org>
Message-ID: <eo3hi6-oa4.ln1@nb2.stroeder.com>

Larry kavanagh wrote:
> I need a PYTHON-LDAP package.
> 
> I'm trying to install ploneldap and it tells me I need python-ldap
> package first  .. but I can't find one to match my versions.
> 
> I'm using plone 3.2.2, Python 2.4.4 and Zope 2.10.7 on a Win32 environment.

Did you check all the links on this page?

  http://www.python-ldap.org/download.shtml

There's a MSI installer for Python 2.4 on Win32:

http://pypi.python.org/packages/2.4/p/python-ldap/python-ldap-2.3.8.win32-py2.4.exe#md5=35da547711280c18bd4ccd6e637cdf9b

There has been an update of the .egg files recently (also link on the
download page above).

Ciao, Michael.

-- 
Michael Str?der
E-Mail: michael at stroeder.com
http://www.stroeder.com


From xahlee at gmail.com  Thu Jul  9 08:19:29 2009
From: xahlee at gmail.com (Xah Lee)
Date: Thu, 9 Jul 2009 05:19:29 -0700 (PDT)
Subject: OT: unix to Windows technology
References: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
	<4a54ceb0$0$5898$607ed4bc@cv.net>
	<16430ee7-888e-42ef-9c84-14df4b78ee04@p36g2000prn.googlegroups.com>
Message-ID: <0de99585-6a35-498d-b5d1-6eb8724c41b3@m3g2000pri.googlegroups.com>

a fried showed me this today:

http://xahlee.org/funny/Microsoft_eula.html

not sure which site originally reported it.

  Xah
? http://xahlee.org/

?


From user at example.net  Thu Jul  9 08:26:37 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 14:26:37 +0200
Subject: older pythons
In-Reply-To: <Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
	<Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
Message-ID: <4a55e1fb$0$1116$4fafbaef@reader3.news.tin.it>

Lie Ryan wrote:
> superpollo wrote:
> 
>>Lie Ryan wrote:
>>
>>
>>>AFAIK, no major linux distributions have officially ported to python
>>>3.x.
>>
>>http://packages.debian.org/experimental/python3.1
>>
>>thanks for help
> 
> 
> Note the word "experimental"

i noticed. isn't experimental official? i thought it was...

thanks for your reply

bye and god bless you


From marco at sferacarta.com  Thu Jul  9 08:37:11 2009
From: marco at sferacarta.com (Marco Mariani)
Date: Thu, 09 Jul 2009 14:37:11 +0200
Subject: older pythons
In-Reply-To: <4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
Message-ID: <Xvl5m.4792$vG4.2383@tornado.fastwebnet.it>

superpollo wrote:

> what i was asking for is about a way to *INSTALL* and mantain different 
> python versions, a task i think is not unusal for developers.

Check out virtualenv, I ask myself how I could work without it.

http://pypi.python.org/pypi/virtualenv



From lie.1296 at gmail.com  Thu Jul  9 08:37:30 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 12:37:30 GMT
Subject: property using a classmethod
In-Reply-To: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
Message-ID: <ewl5m.3746$ze1.3371@news-server.bigpond.net.au>

Emanuele D'Arrigo wrote:
> Greetings,
> 
> today I did something like this:
> 
> class MyClass(object):
> 
>     @classmethod
>     def myClassMethod(self):
>          print "ham"
> 
>      myProperty = property(myClassMethod, None, None)
> 
> As many of you know this doesn't work and returns a TypeError: the
> object passed to the property is not a callable function but a
> classmethod object, which isn't callable at all.

That code runs fine for me. Although I doubt the behavior is what you
wanted to do.

> So, how do I do this?
> Ultimately all I want is a non-callable class-level attribute
> MyClass.myProperty that gives the result of MyClass.myClassMethod().

This works like what you seem to want (it's ugly):

class MyClass(object):
    class _MyClass(object):
        @classmethod
        def myClassMethod(cls):
            return 'ham'
        @property
        def myProperty(self):
            return MyClass._MyClass.myClassMethod()
    @classmethod
    def myClassMethod(cls):
        return MyClass._MyClass.myClassMethod()
    @property
    def myProperty(self):
        return MyClass._MyClass.myClassMethod()

    def __call__(self, *args, **kargs):
        # this is __init__
        return MyClass._MyClass(*args, **kargs)
# note this is NOT a real MyClass instantiation
MyClass = MyClass()

$ python -i ./strangeclass.py
>>> MyClass.myClassMethod()
'ham'
>>> MyClass.myProperty
'ham'
>>> mc = MyClass()
>>> mc.myProperty
'ham'
>>> mc.myClassMethod()
'ham'


From mukherjee.tanmoy at gmail.com  Thu Jul  9 08:43:57 2009
From: mukherjee.tanmoy at gmail.com (Tanmoy)
Date: Thu, 9 Jul 2009 18:13:57 +0530
Subject: Hello
Message-ID: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>

>
> Hello ,
>          When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
> problem.
>
> When i==10 you append another empty list to arr, so arr[i] is arr[10].
> Index error because there's no arr[10], only arr[0] and arr[1].
>
> Thanks for your prompt reply...
>
> How can i pass this problem
>
>  You could try appending to arr[-1] instead.

Better still:

   ...
   row = []
   for j in range(0,1001,1):
         row.append(i+j)
   arr.append(row)
   ...
I tried both the ways... the only thing is its not coming like 0 10
20.......1000 . Its coming like 0,1,2,........1000.....Any answer to the
problem.
Thanks
Tanmoy Mukherjee
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/b9ae7baf/attachment.html>

From davea at ieee.org  Thu Jul  9 08:44:18 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 08:44:18 -0400
Subject: function local namespace question
In-Reply-To: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
References: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
Message-ID: <4A55E622.3050906@ieee.org>

Paul LaFollette wrote:
> Kind people,
>
> Using Python 3.1 under FreeBSD and WinXP.
>
> I've been tearing my hair out trying to solve this myself, but I need
> to ask for help.   I want (for obscure reasons) to be able to log
> transactions in the namespace(s) of a script.  Specifically I would
> like to log creation of identifiers, changes in the binding of
> identifiers ("assignment") and lookups.  This turns out to be pretty
> easy in the global and local namespaces... I simply subclass dict,
> override the appropriate operations to include the logging operations
> I want, and then exec the code using my dictionaries as the global and
> local namespaces.  All  of this  works just dandy until I try to
> extend it to functions.
>
> I cannot figure out any way to get a hook into the local namespace of
> a user defined function.  I have tried making a wrapper class that
> grabs the function call and then uses exec to invoke
> myfunction.__code__ with my own dictionaries.  This runs the (no
> argument) function properly (losing the return value, but I can deal
> with that) but never accesses the local logging dictionary that I
> specify in the exec() call. Perhaps the local namespace of a function
> is not a dict at all?
>
> Anyway, is there any way (however clumsy) to do what I want to do?
> Thank you for your help.
> Paul
>
> ---------------------------
> Paul LaFollette
> CIS Department
> Temple University
> paul.lafollette(at)temple.edu
> www.cis.temple.edu/~lafollet
>
>   
Is there a way?  Undoubtedly.

The simplest way that occurs to me is to have a pre-pass that rewrites 
the .pyc files, adding instrumentation to the byte-code.  You could also 
recompile the Python interpreter, with some extra hooks in it.  That 
could get tricky, as you don't want to instrument the code that's doing 
the tracking.  Fnally, you could hook into the byte-code loader, doing 
the changes at that time.

As always, if the code is for commercial use, beware of infringing on 
patents.  I have a few in the 3rd area (though the ownership is with 
other companies;  I was just the inventor.)

DaveA



From deets at nospam.web.de  Thu Jul  9 08:54:25 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 09 Jul 2009 14:54:25 +0200
Subject: function local namespace question
References: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
	<mailman.2887.1247143473.8015.python-list@python.org>
Message-ID: <7bm7bsF22aoa9U1@mid.uni-berlin.de>

Dave Angel wrote:

> Paul LaFollette wrote:
>> Kind people,
>>
>> Using Python 3.1 under FreeBSD and WinXP.
>>
>> I've been tearing my hair out trying to solve this myself, but I need
>> to ask for help.   I want (for obscure reasons) to be able to log
>> transactions in the namespace(s) of a script.  Specifically I would
>> like to log creation of identifiers, changes in the binding of
>> identifiers ("assignment") and lookups.  This turns out to be pretty
>> easy in the global and local namespaces... I simply subclass dict,
>> override the appropriate operations to include the logging operations
>> I want, and then exec the code using my dictionaries as the global and
>> local namespaces.  All  of this  works just dandy until I try to
>> extend it to functions.
>>
>> I cannot figure out any way to get a hook into the local namespace of
>> a user defined function.  I have tried making a wrapper class that
>> grabs the function call and then uses exec to invoke
>> myfunction.__code__ with my own dictionaries.  This runs the (no
>> argument) function properly (losing the return value, but I can deal
>> with that) but never accesses the local logging dictionary that I
>> specify in the exec() call. Perhaps the local namespace of a function
>> is not a dict at all?
>>
>> Anyway, is there any way (however clumsy) to do what I want to do?

You might consider using the trace-functionality of python, exposed throug

 sys.settrace

It's very expensive of course to do that.

Diez


From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul  9 08:56:18 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 09 Jul 2009 14:56:18 +0200
Subject: property using a classmethod
In-Reply-To: <ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
Message-ID: <4a55e8e0$0$8041$426a34cc@news.free.fr>

Lie Ryan a ?crit :
> Emanuele D'Arrigo wrote:
(snip)
>> Ultimately all I want is a non-callable class-level attribute
>> MyClass.myProperty that gives the result of MyClass.myClassMethod().
> 
> This works like what you seem to want (it's ugly):

Ugly, indeed. And an extreme case of arbitrary overcomplexification too :-/

(snip rube goldberg code)



From user at example.net  Thu Jul  9 09:04:30 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 15:04:30 +0200
Subject: older pythons
In-Reply-To: <Xvl5m.4792$vG4.2383@tornado.fastwebnet.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Xvl5m.4792$vG4.2383@tornado.fastwebnet.it>
Message-ID: <4a55eadd$0$1108$4fafbaef@reader3.news.tin.it>

Marco Mariani wrote:
> superpollo wrote:
> 
>> what i was asking for is about a way to *INSTALL* and mantain 
>> different python versions, a task i think is not unusal for developers.
> 
> 
> Check out virtualenv, I ask myself how I could work without it.
> 
> http://pypi.python.org/pypi/virtualenv
> 

much obliged!


From lie.1296 at gmail.com  Thu Jul  9 09:20:19 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 13:20:19 GMT
Subject: Catching control-C
In-Reply-To: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <n8m5m.3759$ze1.2493@news-server.bigpond.net.au>

Michael Mossey wrote:
> On Jul 6, 2:47 pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>>
>>> What is required in a python program to make sure it catches a  
>>> control-
>>> c on the command-line? Do some i/o? The OS here is Linux.
>> You can use a try/except to catch a KeyboardInterrupt exception, or  
>> you can trap it using the signal module:http://docs.python.org/library/signal.html
>>
>> You want to trap SIGINT.
>>
>> HTH
>> Philip
> 
> Thanks to both of you. However, my question is also about whether I
> need to be doing i/o or some similar operation for my program to
> notice in any shape or form that Control-C has been pressed. In the
> past, I've written Python programs that go about their business
> ignoring Ctrl-C. Other programs respond to it immediately by exiting.
> I think the difference is that the latter programs are doing i/o. But
> I want to understand better what the "secret" is to responding to a
> ctrl-C in any shape or form.
> 
> For example, does trapping SIGINT always work, regardless of what my
> process is doing?
> 
> Thanks,
> Mike

Are you asking: "when would the python interpreter process
KeyboardInterrupt?"

In a multi threaded python program (where KeyboardInterrupt doesn't
always work), only the main thread can process KeyboardInterrupt; thus
the main thread must regain control before the interrupt is raised.
Normally, python will context switch (i.e. thread switch) every 100
interpreter "ticks", but when the interpreter received a SIGINT, the
interpreter will try to context switch as fast as it can (every tick) to
allow the main thread to regain control. So the answer is in
multithreaded python program: "when the main thread regains control"

In single threaded python program, the currently running thread is
always the main thread (which can handle KeyboardInterrupt). I believe
SIGINT is checked at every ticks. But SIGINT cannot interrupt atomic
operations (i.e. it cannot interrupt long operations that takes a single
tick).

An example, where python have difficulties processing KeyboardInterrupt:
>>> print 'foo'*10000000
...foofoofoo...
because printing a string is an atomic operation

I believe a tick in python is equivalent to a single bytecode, but
please correct me if I'm wrong.


From python at mrabarnett.plus.com  Thu Jul  9 09:25:36 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 09 Jul 2009 14:25:36 +0100
Subject: Hello
In-Reply-To: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
References: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
Message-ID: <4A55EFD0.7080408@mrabarnett.plus.com>

Tanmoy wrote:
>     Hello ,
>              When i==0 you append an empty list to arr, so arr[i] is
>     arr[0]. No
>     problem.
> 
>     When i==10 you append another empty list to arr, so arr[i] is arr[10].
>     Index error because there's no arr[10], only arr[0] and arr[1].
>      
>     Thanks for your prompt reply...
> 
>     How can i pass this problem
> 
> You could try appending to arr[-1] instead.
> 
> Better still:
> 
>    ...
>    row = []
>    for j in range(0,1001,1):
>          row.append(i+j)
>    arr.append(row)
>    ...
> I tried both the ways... the only thing is its not coming like 0 10 
> 20.......1000 . Its coming like 0,1,2,........1000.....Any answer to the 
> problem.
> 
Each row should be 1 more than the previous row and each column should
be 10 more than the previous column. Just swap your ranges.


From Lacrima.Maxim at gmail.com  Thu Jul  9 09:28:07 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Thu, 9 Jul 2009 06:28:07 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
	<m27hyi9jof.fsf@cs.uu.nl>
Message-ID: <cafc471d-e1c3-4024-8090-898408415d8f@t13g2000yqt.googlegroups.com>

On Jul 9, 2:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Lacrima <Lacrima.Ma... at gmail.com> (L) wrote:
> >L> Thanks for your reply!
> >L> My file name is 'trains.py'.
> >L> When I do C-h k C-c RET, it shows me help from manual: "C-c RET runs
> >L> the command py-execute-import-or-reload
> >L> ? ?which is an interactive Lisp function in `python-mode'..." and so
> >L> on.
> >L> And still when I do C-c RET, I receive "(Shell command succeeded with
> >L> no output)"
> >L> Any more help would be really appreciated, because I am newbie with
> >L> Emacs.
>
> I tested it and I can get this message also. It happens when you have no
> Python shell running (*Python* buffer). The python code is then executed
> by calling the python shell command and catching the output. This output
> is displayed in the *Python Output* buffer. It happens also with C-c C-c
> and it will give the same message.
>
> There is a difference, however between C-c C-x and C-c RET: The latter
> will import your module, and most modules are written such that
> importing them doesn't print anything. If you add something like
> print "test" and the end of file, then "test" will appear in the *Python
> Output* ?buffer.
>
> If your file has the print "hello world" statement it should display in
> the *Python Output* buffer. I checked that.
>
> On the other hand, if you have a python shell running you must make sure
> (e.g. with the cd command) that its working directory is the directory
> where your python file is located, otherwise the import statement will
> not find your file. Unless it is somewhere in the python path. Also the
> *Python* buffer will not automatically pop up if it is not visible, in
> contrast with the *Python Output* buffer.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

Thank you for really useful and detailed explanation. Now I can test
my code using Emacs.
But I think it works for me in a little bit different way.
My file contains only the print 'hello world'.
If I have no python shell running, then:
a) C-c RET opens *Python Output* buffer without any output and with
'Shell command succeeded with no output' message at the bottom
b) C-c C-c opens *Python Output* with appropriate 'hello world'
message.

Then I run python shell with C-c ! command. And:
a) C-c RET opens *Python* buffer and prints 'hello world' in the
python shell
b) C-c C-c gives the same result.

With regards, Max


From davea at ieee.org  Thu Jul  9 09:28:29 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 09:28:29 -0400
Subject: tough-to-explain Python
In-Reply-To: <7blh0eF23r79rU1@mid.individual.net>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2847.1247068773.8015.python-list@python.org>
	<7blh0eF23r79rU1@mid.individual.net>
Message-ID: <4A55F07D.7040400@ieee.org>

greg wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
>> By the time I graduated, I had five six-level languages
>                                       ^^^
>
> Are they languages that you have to edit using vi? :-)
>
Back then I didn't need glasses.  That was of course intended to be  
"six high-level languages"




From shinejose22 at gmail.com  Thu Jul  9 09:40:18 2009
From: shinejose22 at gmail.com (Shine Jose)
Date: Thu, 9 Jul 2009 08:40:18 -0500
Subject: Problem with two instances of PySerial
Message-ID: <a27b2f730907090640od5e09c1g17caf0cdc5b04894@mail.gmail.com>

Hello friends,I am developing an application to read data from serial port
and display it on the screen using GUI developed in pyQT. For this I have
instantiated the GUI as well as pySerial objects in the main thread. I have
provided a button 'Read' which when clicked by the user reads from the
serial port using read() method of pySerial. However, for debugging purposes
I also want to poll the serial port continuously for arrival of data and
display on screen. I achieve this by creating a separate worker thread to
poll the serial port for arrival of data and then updating the required
widget in main thread of program. For polling the serial port, I create a
separate instance of pySerial object. However, I am unable to read any data
in the worker thread. Can the reason for this be 2 instances of pySerial
objects being connected to serial port. The reason I had this doubt was
because Serial.Connect() in the worker thread did not throw any exception &
isOpen() method returns true.
I request you to help me in figuring out the problem.

-- 
Regards,
Shine Jose
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/fd28dc16/attachment.html>

From davea at ieee.org  Thu Jul  9 09:41:38 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 09:41:38 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <4A55F392.3080404@ieee.org>

m.reddy prasad reddy wrote:
> can any one tell me how to write assembly language programs in python...if
> no is there any other way to write the programs in python
>
> Reddi prasad reddy
> ph.no:09958083797
>
>   
Assembly language is a different programming language than Python.  You 
can use both in the same process, much in the same way you can use C or 
C++ with Python.  In fact, some of the system DLL's are written (partly) 
in assembler, though mostly in C or C++.

You'll need to tell us what your real goal is.  Are you a python 
programmer trying to optimize some loop?  Are you taking a course in 
assembler, and hope that somehow Python will help?  Do you have Python 
installed on your system?  What system is it?

As far as I know, Python has no "inline assembler" mode, as C does.   So 
anything written in assembler would be in a separate DLL, not mixed in 
your .py files.  It's not hard to mix assembly files with C or C++ files 
(or Pascal, or dozens of other compiled languages), and link them into a 
single DLL.  But Python's access to that DLL will be done through a 
module like ctypes, or SWIG.


DaveA


From nleioatt at gmail.com  Thu Jul  9 09:42:06 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 9 Jul 2009 06:42:06 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
Message-ID: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>

I've seen a lot of posts on this problem, but none seems to help.
Here is the code:
/code

file = open(prefix1)
text = file.readlines()
len = len(text)
fields = text[1].split()
num_rows = int(fields[1])
num_cols = int(fields[2])

U1_matrix = []

print fields
print repr(fields)
print len(fields)

for line in text[2: num_rows+2]:
    fields = line.split()
#    print "fields", fields, line
    for i in range(len(fields)):
        fields[i] = float(fields[i])
    U1_matrix.append(fields)

/*code

prefix is a space/line delimited ascii file that represents a 2D
matrix.  i'm trying to read in 2 matrices from different files, strip
away the header stuff and then take the dot product of the 2
matrices.  any help is much appreciated.

thanks,
nick


From gabriel.rossetti at arimaz.com  Thu Jul  9 09:43:01 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Thu, 09 Jul 2009 15:43:01 +0200
Subject: Blocking XMPP API?
Message-ID: <4A55F3E5.8040800@arimaz.com>

Hello everyone,

I am looking for blocking XMPP API. I'm wanting to make a webservice 
that uses XMPP, but all the XMPP libs I find are non-blocking (i.e. w/ 
callbacks). I'd like to be able to do something like :

cl = Client("test at domain.com/res01", "password",)
msg = "<m....."
result = cl.send(msg)
print "I got '%s'" % str(result)

any ideas? Using Java I have Smack which can either get msgs sync or 
async, but I found nothing that can do this in Python.

Thanks,
Gabriel

-- 
Arimaz SA
Ing?nieur en Informatique
Av. du 24 Janvier 11
Ateliers de la Ville de Renens, Atelier 5
1020 Renens, Switzerland
www.arimaz.com
www.mydeskfriend.com
Mob: +41-(0)79-539-0069
Tel: +41-(0)21-566-7343



From benjamin.kaplan at case.edu  Thu Jul  9 09:47:53 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Thu, 9 Jul 2009 09:47:53 -0400
Subject: tough-to-explain Python
In-Reply-To: <b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
Message-ID: <ec96e1390907090647n572055dbq306b2cd48f78645d@mail.gmail.com>

On Thu, Jul 9, 2009 at 1:05 AM, Simon Forman<sajmikins at gmail.com> wrote:
> Everyone gets so caught up in programming via languages that
> you get, well, people trying to teach "Computer Programming" as if it
> were only necessary to grok a language, rather than grokking /symbol
> manipulation/ itself.
>
>

+1 QOTW.

I'm a CS major and this is exactly what I see happening in the intro
to CS courses. In class, the "Intro to Programming" students are
showed how to write Java code. Then they try their homework and are
completely lost because they were never taught how to think like a
programmer so they don't understand how to approach the question.


From lutz.horn at fastmail.fm  Thu Jul  9 09:50:02 2009
From: lutz.horn at fastmail.fm (Lutz Horn)
Date: Thu, 09 Jul 2009 15:50:02 +0200
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <4A55F58A.9060003@fastmail.fm>

Hi,

Nick schrieb:
> I've seen a lot of posts on this problem, but none seems to help.

Could you please post a sample input file and the exact error message?

Thanks
Lutz
-- 
Strike Out ? http://www.fourmilab.ch/documents/strikeout


From benjamin.kaplan at case.edu  Thu Jul  9 09:51:49 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Thu, 9 Jul 2009 09:51:49 -0400
Subject: older pythons
In-Reply-To: <Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
	<Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
Message-ID: <ec96e1390907090651y30184f42jb32fa76c99255849@mail.gmail.com>

On Thu, Jul 9, 2009 at 8:10 AM, Lie Ryan<lie.1296 at gmail.com> wrote:
> superpollo wrote:
>> Lie Ryan wrote:
>>
>>> AFAIK, no major linux distributions have officially ported to python
>>> 3.x.
>>
>> http://packages.debian.org/experimental/python3.1
>>
>> thanks for help
>
> Note the word "experimental"

Assuming that Debian does the same thing as Ubuntu (which is highly
likely), Python3.1 won't install itself as the default. Too many
system features depend on Python 2.x.
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From fridrik at pyth.net  Thu Jul  9 09:53:29 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 13:53:29 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <3A693537-927D-44B1-840A-D97FACFB6809@pyth.net>

Look at:

   len = len(text)

You're overriding `len` (a built-in method), with an integer  
(`len(text)`).  You then call:

   for i in range(len(fields)):

But `len` is no longer a callable, but merely an integer.

Regards,
Fri?rik M?r

P.S. While this is a fairly obvious problem it's usually a good idea  
to post working code and a traceback when requesting help.

From gagsl-py2 at yahoo.com.ar  Thu Jul  9 09:53:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 10:53:42 -0300
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
	<mailman.2880.1247134886.8015.python-list@python.org>
	<652cca82-44a3-473f-b640-c2336a9cf929@v15g2000prn.googlegroups.com>
Message-ID: <op.uwszjsc2x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 09 Jul 2009 07:53:29 -0300, Rajat <rajat.dudeja at gmail.com>  
escribi?:

> Thanks Tim for the details. Just further on this, my whole idea is to
> close the wordpad / notepad application so that I can delete the file
> and the directory where this file resides.
>
> With notepad it is no more a problem. But I'm concerned about the
> wordpad now.

I don't see Wordpad keeping the file open either.
If you can't remove the file, use "handle.exe filename.txt" to discover  
which process is holding it open, as Tim already explained.

-- 
Gabriel Genellina



From R.Brodie at rl.ac.uk  Thu Jul  9 10:02:27 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Thu, 9 Jul 2009 15:02:27 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <h34t9k$kp8$1@south.jnrs.ja.net>


"Nick" <nleioatt at gmail.com> wrote in message 
news:e54c4461-c0b7-42fb-8542-cefd7bf5f89f at h18g2000yqj.googlegroups.com...

> file = open(prefix1)
> text = file.readlines()
> len = len(text)

You have redefined two built-in functions "file" and "len" in the first three lines.
This is usually considered poor practice. Stick to meaningless variable names,
it's safer (only joking).

TypeError: 'int' object is not callable". This means that something you thought
was a function is in fact an integer. It's helpful to post/look at the line number of
the error; "how is this line failing", is much easier to answer than
"how is my program failing".

print len(fields)

Here len is an integer, because you redefined it in line 3. I'm guessing this is the
problem. 




From davea at ieee.org  Thu Jul  9 10:04:23 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 10:04:23 -0400
Subject: Hello
In-Reply-To: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
References: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
Message-ID: <4A55F8E7.6090304@ieee.org>

You could pick a much better title.  And apparently you started a new 
thread with this one.  When responding to an existing message, you ought 
to reply-all to the existing message, rather than starting a new thread.

Tanmoy wrote:
>> Hello ,
>>          When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
>> problem.
>>
>> When i==10 you append another empty list to arr, so arr[i] is arr[10].
>> Index error because there's no arr[10], only arr[0] and arr[1].
>>
>> Thanks for your prompt reply...
>>
>> How can i pass this problem
>>
>>  You could try appending to arr[-1] instead.
>>     
>
> Better still:
>
>    ...
>    row = []
>    for j in range(0,1001,1):
>          row.append(i+j)
>    arr.append(row)
>    ...
> I tried both the ways... the only thing is its not coming like 0 10
> 20.......1000 . Its coming like 0,1,2,........1000.....Any answer to the
> problem.
> Thanks
> Tanmoy Mukherjee
>
>   
If you want the row to count by 10's you have to build it that way.  You 
have the arguments to the ranges backwards.  Try:


arr=[]
for i in range(1001):
   row = []
   for j in range(0,1010,10):
         row.append(i+j)
   arr.append(row)

Coincidentally, once you reverse them, the original problem would go 
away.  But this is better anyway, as it makes it clear what's 
happening.  You are building 1001 rows, each containing non-contiguous 
numbers.

DaveA



From timmyt at smarttypes.org  Thu Jul  9 10:07:52 2009
From: timmyt at smarttypes.org (timmyt)
Date: Thu, 9 Jul 2009 07:07:52 -0700 (PDT)
Subject: a little wsgi framework
References: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
	<4a53132c$0$10839$426a34cc@news.free.fr>
Message-ID: <103cb80e-5a5a-4c41-ae7c-c0ae122cfebf@b25g2000prb.googlegroups.com>

On Jul 7, 5:19?am, Bruno Desthuilliers <bruno.
42.desthuilli... at websiteburo.invalid> wrote:
> timmyt a ?crit :
>
> > i'm interested in getting opinions on a smallwsgiframework i
> > assembled from webob, sqlalchemy, genshi, and various code fragments i
> > found on the inter-tubes
>
> > here is the interesting glue - any comments / suggestions would be
> > much appreciated
>
> <meta>
> Well... My first comment would be about the usefulness of yet another
> Python web framework, but let's not worry about this...
> </meta>
>
> > ------------------
> > thewsgiapp
> > ------------------
> > def application(environ, start_response):
> > ? ? path = environ.get('PATH_INFO', '').lstrip('/')
>
> > ? ? for regex, callback in urls:
> > ? ? ? ? match = re.search(regex, path)
>
> I don't know where these "urls" come from. But anyway : if they live in
> some sort of long-running process, you may want to precompile them.
>
> > ? ? ? ? if match:
> > ? ? ? ? ? ? environ['myapp.url_args'] = match.groups()
> > ? ? ? ? ? ? request = webob.Request(environ)
>
> > ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? return callback(request, start_response)
> > ? ? ? ? ? ? except Exception, ex:
>
> How are redirect etc handled ?
>
> > ? ? ? ? ? ? ? ? start_response('500 Internal Server Error', [('Content-
> > Type', 'text/plain')])
> > ? ? ? ? ? ? ? ? return [traceback.format_exc()]
>
> A configuration option controlling the display of the traceback would be
> fine - I surely don't want the traceback being displayed to anyone when
> ? the app goes into production.
>
> Also, logging the error and traceback might be useful.
>
> > ? ? start_response('404 Not Found', [('Content-Type', 'text/plain')])
> > ? ? return ["Couldn't find the URL specified."]
>
> And in both cases, having the ability to use "custom" 500 and 404 pages
> might be nice too.
>
>
>
> > ----------------------------------
> > the controller decorator
> > ----------------------------------
> > def web_decorator(filename, method='html'):
>
> > ? ? def decorator(target):
>
> May I suggest some renaming here ?
>
> filename => path (or 'template_path' ?)
> method ? => content_type
> target ? => controller or function or callback or....
>
> > ? ? ? ? def wrapper(request, start_response):
>
> > ? ? ? ? ? ? #genshi TemplateLoader
> > ? ? ? ? ? ? template = loader.load(filename)
>
> > ? ? ? ? ? ? global config
>
> Probably not thread-safe....
>
> > ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? return_dict = target(request, start_response)
> > ? ? ? ? ? ? ? ? return_string = template.generate(**return_dict).render
> > (method)
>
> Renaming again:
> return_dict => context
> return_string => data or text or ???
>
> > ? ? ? ? ? ? ? ? config['database.Session'].commit()
> > ? ? ? ? ? ? except:
> > ? ? ? ? ? ? ? ? config['database.Session'].rollback()
> > ? ? ? ? ? ? ? ? raise
> > ? ? ? ? ? ? finally:
> > ? ? ? ? ? ? ? ? config['database.Session'].remove()
>
> This doesn't leave much control on transactions... Sometimes you want to
> handle it manually one way or another.
>
> > ? ? ? ? ? ? #TODO: alter 'Content-Type' per method being passed
> > ? ? ? ? ? ? start_response('200 OK', [('Content-Type', 'text/html')])
> > ? ? ? ? ? ? return [return_string]
>
> Ok, so here again, I don't understand how redirects can work. Also, if
> you do use start_response here, I don't get why you still pass it to the
> callback function.
>
> > ? ? ? ? return wrapper
>
> > ? ? return decorator
>
> slightly OT, but preserving infos on the decorated function might help
> too (introspection, debugging etc).
>
> My 2 cents...

thank you gentlemen

i'm now looking for Redirect exceptions as well, and returning the
appropriate response code (stole this idea from turbogears)

i like doing the response codes and exceptions myself which is why i'm
not using the webob response - i think it's more explicit and
straightforward

the conditional display of errors goes without say - that will be
trivial to add

the 'global config' line was an error - config is a module level
variable set before the application definition

i assume as long as i don't write to the config variable within the
application it is thread-safe - is that correct

the underlying assumption is the wsgi application setup does not have
to be thread safe - this is only run once per process








From nleioatt at gmail.com  Thu Jul  9 10:08:05 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 9 Jul 2009 07:08:05 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
Message-ID: <75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>

On Jul 9, 10:02 am, "Richard Brodie" <R.Bro... at rl.ac.uk> wrote:
> "Nick" <nleio... at gmail.com> wrote in message
>
> news:e54c4461-c0b7-42fb-8542-cefd7bf5f89f at h18g2000yqj.googlegroups.com...
>
> > file = open(prefix1)
> > text = file.readlines()
> > len = len(text)
>
> You have redefined two built-in functions "file" and "len" in the first three lines.
> This is usually considered poor practice. Stick to meaningless variable names,
> it's safer (only joking).
>
> TypeError: 'int' object is not callable". This means that something you thought
> was a function is in fact an integer. It's helpful to post/look at the line number of
> the error; "how is this line failing", is much easier to answer than
> "how is my program failing".
>
> print len(fields)
>
> Here len is an integer, because you redefined it in line 3. I'm guessing this is the
> problem.

thanks for spotting the obvious errors, its my 2nd day programming
python in about 3 years.
fridrick, code should be workable with the exception of the
errors...thats the whole program

Thanks again for all the help problem fixed


From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul  9 10:24:19 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 09 Jul 2009 16:24:19 +0200
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <4a55fd80$0$9943$426a74cc@news.free.fr>

Nick a ?crit :
> I've seen a lot of posts on this problem, but none seems to help.
> Here is the code:
> /code
> 
> file = open(prefix1)

shadows the builtin 'file' type.


> text = file.readlines()
> len = len(text)

shadows the builtin 'len' function.

> fields = text[1].split()
> num_rows = int(fields[1])
> num_cols = int(fields[2])
> 
> U1_matrix = []
> 
> print fields
> print repr(fields)
> print len(fields)

And here's your problem - 'len' is now bound to the result of the 
previous call to len(text).

Hint : Python's functions, classes and modules are objects too, and 
don't live in a distinct namespace. So _don't_ use builtin's types / 
functions / etc names as identifiers.

HTH


From davea at ieee.org  Thu Jul  9 10:52:14 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 10:52:14 -0400
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <4A56041E.6020206@ieee.org>

Nick wrote:
> I've seen a lot of posts on this problem, but none seems to help.
> Here is the code:
> /code
>
> file = open(prefix1)
> text = file.readlines()
> len = len(text)
> fields = text[1].split()
> num_rows = int(fields[1])
> num_cols = int(fields[2])
>
> U1_matrix = []
>
> print fields
> print repr(fields)
> print len(fields)
>
> for line in text[2: num_rows+2]:
>     fields = line.split()
> #    print "fields", fields, line
>     for i in range(len(fields)):
>         fields[i] = float(fields[i])
>     U1_matrix.append(fields)
>
> /*code
>
> prefix is a space/line delimited ascii file that represents a 2D
> matrix.  i'm trying to read in 2 matrices from different files, strip
> away the header stuff and then take the dot product of the 2
> matrices.  any help is much appreciated.
>
> thanks,
> nick
>
>   
You have at least two problems with that code, one of which is causing 
your symptom.

Both 'file' and 'len' are defined in the standard library, and shouldn't 
be redefined in your code.  And your problem is that after you redefined 
'len', you then tried to use it in its original meaning.


Rename those two and you'll get further.

And it would have saved lots of time for lots of people if you included 
sample data and the actual error message, marking where in your code it 
occurs.  Once you know it's complaining about the len() call, it's not 
too hard to figure out that the problem was you rebound the len 
attribute from a function to an integer.

Traceback (most recent call last):
  File "M:\Programming\Python\sources\dummy\echo2.py", line 21, in <module>
    print len(fields)
TypeError: 'int' object is not callable


DaveA


From jcd at sdf.lonestar.org  Thu Jul  9 11:15:41 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Thu, 09 Jul 2009 11:15:41 -0400
Subject: count
In-Reply-To: <e4a20167-4c63-4ab3-baf2-be1f41c81fd8@a36g2000yqc.googlegroups.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com> <7xbpnuzw4u.fsf@ruckus.brouhaha.com>
	<mailman.2865.1247105487.8015.python-list@python.org>
	<e4a20167-4c63-4ab3-baf2-be1f41c81fd8@a36g2000yqc.googlegroups.com>
Message-ID: <1247152541.3694.45.camel@aalcdl07>

Bearophile wins!  (This only times the loop itself.  It doesn't check
for __len__)

summer:5
0:00:00.000051
bearophile:5
0:00:00.000009
summer:50
0:00:00.000030
bearophile:50
0:00:00.000013
summer:500
0:00:00.000077
bearophile:500
0:00:00.000053
summer:5000
0:00:00.000575
bearophile:5000
0:00:00.000473
summer:50000
0:00:00.005583
bearophile:50000
0:00:00.004625
summer:500000
0:00:00.055834
bearophile:500000
0:00:00.046137
summer:5000000
0:00:00.426734
bearophile:5000000
0:00:00.349573
summer:50000000
0:00:04.180920
bearophile:50000000
0:00:03.652311
summer:500000000
0:00:42.647885
bearophile: 500000000
0:00:35.190550

On Thu, 2009-07-09 at 04:04 -0700, Bearophile wrote:
> Paul Rubin:
> > print x, sum(1 for _ in g)
> 
> Don't use that, use my function :-) If g has a __len__ you are wasting
> time. And sum(1 ...) is (on my PC) slower.
> 
> 
> J. Clifford Dyer:
> > if __name__ == '__main__':
> >     test_func(summer, 10000000)
> >     test_func(tupler, 10000000)
> >     test_func(summer, 100000000)
> >     test_func(tupler, 100000000)
> 
> Have you forgotten my function?
> 
> Bye,
> bearophile



From ethan at stoneleaf.us  Thu Jul  9 11:16:30 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 09 Jul 2009 08:16:30 -0700
Subject: tough-to-explain Python
In-Reply-To: <007075aa$0$9711$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>
	<007075aa$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <4A5609CE.70807@stoneleaf.us>

Steven D'Aprano wrote:
> 
> There is some evidence that 30-60% of people simply cannot learn to 
> program, no matter how you teach them:
> 
> http://www.codinghorror.com/blog/archives/000635.html
> http://www.cs.mdx.ac.uk/research/PhDArea/saeed/
> 
> I'm sympathetic to the idea, but not entirely convinced. Perhaps the 
> problem isn't with the students, but with the teachers, and the 
> languages: 
> 
> http://www.csse.monash.edu.au/~damian/papers/PDF/SevenDeadlySins.pdf
> 
> (My money is that it's a little of both.)
> 
> 

Very interesting articles.  Not suprising (to me, at least) -- everybody 
has their strengths and weaknesses.  I will never be, and could never 
have been, any kind of sports person;  I don't have the right 
personality to be a good people person;  I don't have the knack for 
writing stories.  Not everyone can do anything, or even many things.

~Ethan~


From fridrik at pyth.net  Thu Jul  9 11:30:35 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 15:30:35 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>
Message-ID: <391EDF07-7FCE-4DD2-B510-1EBA7A70D36A@pyth.net>

Previously, I wrote:
>> P.S. While this is a fairly obvious problem it's usually a good  
>> idea to post working code and a traceback when requesting help.

Nick wrote:
> thanks for spotting the obvious errors, its my 2nd day programming
> python in about 3 years.

I'm sorry, my saying it was obvious may have come off a little  
arrogant. My clumsily delivered point was that because it was a small  
snippet of code it didn't take much time to run through for someone  
who codes daily with Python. What you did there was a perfectly  
ordinary thing to do until experience teaches you how Python does  
things. :)

> fridrick, code should be workable with the exception of the
> errors...thats the whole program

You're right, I failed to say it explicitely but I was referring to  
the input file.  In some cases, albeit not this one, problems can  
exist in parsing gotchas.

Regards,
Fri?rik M?r

From robert.kern at gmail.com  Thu Jul  9 11:54:37 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 09 Jul 2009 10:54:37 -0500
Subject: PyQt GUI
In-Reply-To: <5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
Message-ID: <h353rt$kjh$1@ger.gmane.org>

On 2009-07-09 01:27, Helvin wrote:
> On Jul 9, 11:29 am, Robert Kern<robert.k... at gmail.com>  wrote:
>> On 2009-07-08 18:10, Helvin wrote:
>>
>>> Thanks for the fast replies! I will look into how to use VTK now.
>>> Where would I find VTK's explicit support for PyQt?
>> Wrapping/Python/vtk/qt4/ in the VTK sources.
>>
>>> Because I have installed VTK (using its installer) and pyVTK (using
>>> its setup.py file), but how do I actually use it in my code? According
>>> to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
>>> I have tried 'import vtk', but python can't find the vtk module.
>> Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
>> just a library for manipulating VTK files. The VTK Python bindings are part of
>> VTK's distribution itself. Exactly how did you install VTK? Did you compile it
>> yourself?
>
> You mean, when I download VTK, the VTK Python bindings come with it?
> I downloaded VTK from:http://vtk.org/files/release/5.4/

Exactly which file did you download? I don't think the vtk-5.4.x-win32.exe 
installers have the Python bindings. You will need to build VTK from sources.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From psimon at sonic.net  Thu Jul  9 12:02:34 2009
From: psimon at sonic.net (Paul Simon)
Date: Thu, 9 Jul 2009 09:02:34 -0700
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
Message-ID: <4a5615ba$0$95523$742ec2ed@news.sonic.net>


"Peter Otten" <__peter__ at web.de> wrote in message 
news:h3481q$d95$00$1 at news.t-online.com...
> Paul Simon wrote:
>
>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>> news:mailman.2863.1247095339.8015.python-list at python.org...
>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>> I have the "tkinter" problem and need some assistance to straighten it
>>> out.
>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>>> >"step
>>> 1" and cannot import "_tkinter." I do not have that file on my computer,
>>> but
>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>> This python stuff is great, but the documentation frequently
>>> feels like it is just a bit out of my grasp. I realize that all of this
>>> is free but I understand the instructions on the web page to repair only
>>> to the
>>> point of confusion. I'm not an expert. How do I modify my python
>>> configuration? Is there a file that needs to be edited? Which setup.py
>>> file
>>> do I use? Make? or python setup.py build and python setup.py install?
>>> Thanks. I appreciate your help.
>>
>> - How did you install Python?
>> - What Linux distro are you using?
>>
>> Cheers,
>> Chris
>> http://blog.rebertia.com
>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>> something from python.org and installed.  Not sure if it was tarball or
>> zip file.
>
> Zip or tar doesn't matter, you are installing "from source".
>
> Python has to find the necessary include files for tcl/tk. These are in
> separate packages that you have to install before you invoke Python's
> configure script.
>
> I don't know what they are called on your system -- look for tk-dev.rpm,
> tcl-dev.rpm or similar.
>
> You may run into the same problem with other modules like readline.
>
> Peter
>

Thank you Peter.  I understand what you are saying but don't know how to do 
it.  Although I installed from source, I followed a "cookbook" recipe. 
Could you tell me what files to execute, where they might be, and file 
arguments?  I'm just ignorant, not stupid. ;-).

Paul 




From nleioatt at gmail.com  Thu Jul  9 12:04:58 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 9 Jul 2009 09:04:58 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>
	<mailman.2901.1247153447.8015.python-list@python.org>
Message-ID: <ed761421-f881-434c-b5f8-6ab98fce2191@d4g2000yqa.googlegroups.com>

no problem, i understand, i haven't coded anything in literally 2
years, but it was a simple and pretty obvious mistake.  thanks for all
your help,

nick


On Jul 9, 11:30 am, Fri?rik M?r J?nsson <frid... at pyth.net> wrote:
> Previously, I wrote:
> >> P.S. While this is a fairly obvious problem it's usually a good
> >> idea to post working code and a traceback when requesting help.
> Nick wrote:
> > thanks for spotting the obvious errors, its my 2nd day programming
> > python in about 3 years.
>
> I'm sorry, my saying it was obvious may have come off a little
> arrogant. My clumsily delivered point was that because it was a small
> snippet of code it didn't take much time to run through for someone
> who codes daily with Python. What you did there was a perfectly
> ordinary thing to do until experience teaches you how Python does
> things. :)
>
> > fridrick, code should be workable with the exception of the
> > errors...thats the whole program
>
> You're right, I failed to say it explicitely but I was referring to
> the input file.  In some cases, albeit not this one, problems can
> exist in parsing gotchas.
>
> Regards,
> Fri?rik M?r



From tkermode at gmail.com  Thu Jul  9 12:06:45 2009
From: tkermode at gmail.com (Tom Kermode)
Date: Thu, 9 Jul 2009 17:06:45 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <h34t9k$kp8$1@south.jnrs.ja.net>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
Message-ID: <da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>

Hi,

   Do you know a good way to avoid running into this problem?  It
makes sense to suggest not calling variables the same names as
built-in functions, but that's hard for a new python programmer who
doesn't already know what all the built-in functions are. Over time a
programmer will learn which names to avoid, but it's a bit of a
pitfall early on.

Cheers,
Tom



2009/7/9 Richard Brodie <R.Brodie at rl.ac.uk>:
>
> "Nick" <nleioatt at gmail.com> wrote in message
> news:e54c4461-c0b7-42fb-8542-cefd7bf5f89f at h18g2000yqj.googlegroups.com...
>
>> file = open(prefix1)
>> text = file.readlines()
>> len = len(text)
>
> You have redefined two built-in functions "file" and "len" in the first three lines.
> This is usually considered poor practice. Stick to meaningless variable names,
> it's safer (only joking).
>
> TypeError: 'int' object is not callable". This means that something you thought
> was a function is in fact an integer. It's helpful to post/look at the line number of
> the error; "how is this line failing", is much easier to answer than
> "how is my program failing".
>
> print len(fields)
>
> Here len is an integer, because you redefined it in line 3. I'm guessing this is the
> problem.
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.kiloday.com
http://www.fourstopspast.com


From R.Brodie at rl.ac.uk  Thu Jul  9 12:30:42 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Thu, 9 Jul 2009 17:30:42 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com><h34t9k$kp8$1@south.jnrs.ja.net>
	<mailman.2903.1247155607.8015.python-list@python.org>
Message-ID: <h355vi$n7j$1@south.jnrs.ja.net>


"Tom Kermode" <tkermode at gmail.com> wrote in message 
news:mailman.2903.1247155607.8015.python-list at python.org...

> Do you know a good way to avoid running into this problem?  It
> makes sense to suggest not calling variables the same names as
> built-in functions, but that's hard for a new python programmer who
> doesn't already know what all the built-in functions are.

No, but not redefining the ones you actually use is a good start.
Learning to understand the traceback is the more important lesson,
IMHO. It takes a while to tune into what error messages are trying
to tell you; even when you stop making newbie mistakes, you're
going to have to deal with runtime errors from time to time. 




From m at n.d  Thu Jul  9 12:32:41 2009
From: m at n.d (Broken)
Date: Thu, 9 Jul 2009 18:32:41 +0200
Subject: send keys to focused window
Message-ID: <MPG.24c0392b71e8a0eb989680@news.bintube.com>

Hi,
I am new to Python, and I'm miserably failing to send specific keys to 
(say) notepad.

Here is the scenario:
I have notepad open.
My python script is running in the background.
When I press ALT+a I want to intercept the keys and send "?"(ASCII code: 
ALT+0228) instead.

OS: Windows 7
Libraries used: pyHook, SendKeys, pyWin32

Here is my code:

###############################
# -*- coding: cp1252 -*-
import pythoncom, pyHook
from SendKeys import SendKeys

def OnKeyboardEvent(event):
    if event.Alt == 32:         #alt pressed
        if event.Ascii == 97:   #a pressed
            SendKeys("?")
        return False #don't pass to other handlers

# return True to pass the event to other handlers
    return True

# create a hook manager
hm = pyHook.HookManager()
# watch for all mouse events
hm.KeyDown = OnKeyboardEvent
# set the hook
hm.HookKeyboard()
# wait forever
pythoncom.PumpMessages()

###############################

It's largely copied from the pyhook example.
My problem is, I need to somehow disable ALT while sonding the key.

Please help :)


From h at realh.co.uk  Thu Jul  9 12:33:43 2009
From: h at realh.co.uk (Tony Houghton)
Date: Thu, 9 Jul 2009 17:33:43 +0100
Subject: Running a script to build docs from setup.py
Message-ID: <20090709173343.1784710d@realh.co.uk>

I want to write a setup.py script, using distutils, for a python library
called ROX-Lib2 (package name "rox"). The library includes a script to
build HTML documentation from the pydoc strings. I'd like to run that
script from setup.py but I don't know the best way to do that. I've
looked through the manual but I can't find any hooks in distutils for
generating files at install time other than extension modules and .pyc
files. Should I just run the script from somewhere in my setup.py before
calling distutils' setup function?

-- 
TH * http://www.realh.co.uk



From fridrik at pyth.net  Thu Jul  9 12:40:47 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 16:40:47 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
Message-ID: <FE4B2224-3848-4F74-94F7-58196C109670@pyth.net>

Tom Kermode wrote:
> Do you know a good way to avoid running into this problem?  It
> makes sense to suggest not calling variables the same names as
> built-in functions, but that's hard for a new python programmer who
> doesn't already know what all the built-in functions are.

One way is using a code checker like PyChecker[1]. This neat software  
for finding bugs will check for lots of other pitfalls too, but you  
can filter it down to what you need if you're only interested in this  
one.

I don't use an IDE, but this would seem like something for an IDE[2]  
to support if you're into that kind of magic.

Regards,
Fri?rik M?r

[1] http://pychecker.sourceforge.net/
[2] http://wiki.python.org/moin/IntegratedDevelopmentEnvironments

From __peter__ at web.de  Thu Jul  9 13:00:37 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 09 Jul 2009 19:00:37 +0200
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
Message-ID: <h357nj$903$00$1@news.t-online.com>

Paul Simon wrote:

> 
> "Peter Otten" <__peter__ at web.de> wrote in message
> news:h3481q$d95$00$1 at news.t-online.com...
>> Paul Simon wrote:
>>
>>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>>> news:mailman.2863.1247095339.8015.python-list at python.org...
>>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>>> I have the "tkinter" problem and need some assistance to straighten it
>>>> out.
>>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>>>> >"step
>>>> 1" and cannot import "_tkinter." I do not have that file on my
>>>> computer, but
>>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>>> This python stuff is great, but the documentation frequently
>>>> feels like it is just a bit out of my grasp. I realize that all of this
>>>> is free but I understand the instructions on the web page to repair
>>>> only to the
>>>> point of confusion. I'm not an expert. How do I modify my python
>>>> configuration? Is there a file that needs to be edited? Which setup.py
>>>> file
>>>> do I use? Make? or python setup.py build and python setup.py install?
>>>> Thanks. I appreciate your help.
>>>
>>> - How did you install Python?
>>> - What Linux distro are you using?
>>>
>>> Cheers,
>>> Chris
>>> http://blog.rebertia.com
>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not
>>> sure
>>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>> something from python.org and installed.  Not sure if it was tarball or
>>> zip file.
>>
>> Zip or tar doesn't matter, you are installing "from source".
>>
>> Python has to find the necessary include files for tcl/tk. These are in
>> separate packages that you have to install before you invoke Python's
>> configure script.
>>
>> I don't know what they are called on your system -- look for tk-dev.rpm,
>> tcl-dev.rpm or similar.
>>
>> You may run into the same problem with other modules like readline.
>>
>> Peter
>>
> 
> Thank you Peter.  I understand what you are saying but don't know how to
> do
> it.  Although I installed from source, I followed a "cookbook" recipe.
> Could you tell me what files to execute, where they might be, and file
> arguments?  I'm just ignorant, not stupid. ;-).
> 
> Paul

Once you have the necessary development packages for tcl/tk just go into the 
directory where you unzipped the source and

./configure
make
sudo make altinstall

Unfortunately I don't know the names of these packages nor how to install 
them, and Google didn't turn up anything useful.

If you don't get any additional answers here you may try a Mandriva forum 
since this is not a question that requires python knowlegde.

Peter



From duane.kaufman at gmail.com  Thu Jul  9 13:14:29 2009
From: duane.kaufman at gmail.com (TheSeeker)
Date: Thu, 9 Jul 2009 10:14:29 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
Message-ID: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>

Hi,

I am embarking on teaching myself Microsoft UI Automation using Python
as the scripting language.

I have asked some questions in the IronPython users group, but have
yet to get a response, so I thought I would broaden the audience by
asking here.

Specifically, I have a WinForms application I will be wanting to
automate. Does anyone have some Python examples of driving Microsoft
UI Automation they could share with me to get me started? The
structure of the UI automation classes etc. seem quite convoluted, and
I am having difficulty getting my brain wrapped around it.

Alternatives to Microsoft's UI Automation are welcome too, but I have
tried using winguiauto and watsup (along with AutoIt), and there seems
to be severe limitations when using these tools with WinForm
applications.

Thanks in advance,
Duane


From joshua at joshuakugler.com  Thu Jul  9 13:17:25 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Thu, 09 Jul 2009 09:17:25 -0800
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org> <h2up7a$epu$1@ger.gmane.org>
	<h30dfc$ke2$1@ger.gmane.org>
Message-ID: <h358n5$bn6$1@ger.gmane.org>

Joshua Kugler wrote:
> Sorry about that...since pysqlite and APSW are both discusses on the
> pysqlite list, I had made an incorrect assumption. Oops.

"are both discusses?"  Yeef, I must have been out of it.  Discussed, thank
you. :)

j



From usernet at ilthio.net  Thu Jul  9 13:18:49 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 09 Jul 2009 17:18:49 GMT
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
Message-ID: <ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>

On 2009-07-09, TheSeeker <duane.kaufman at gmail.com> wrote:
> Specifically, I have a WinForms application I will be wanting to
> automate. Does anyone have some Python examples of driving Microsoft
> UI Automation they could share with me to get me started? The
> structure of the UI automation classes etc. seem quite convoluted, and
> I am having difficulty getting my brain wrapped around it.

If you find a way to work through the UI using the keyboard (tabs, etc);
then, you can send it keyboard commands using WScript.WshShell.SendKeys():

http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx


From steve at REMOVE-THIS-cybersource.com.au  Thu Jul  9 13:20:14 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 09 Jul 2009 17:20:14 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
Message-ID: <007201bc$0$9710$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:

> The core abstractions of [mechanical] computation are just not that
> complicated.  You can teach them to anybody in about a half an hour,
> drunk. I have.

That's *easy*. Anyone can teach the most complicated and abstract 
principles of any topic at all drunk. What's hard is doing it sober.

http://stackoverflow.com/questions/63668/confessions-of-your-worst-wtf-
moment-what-not-to-do/350267#350267

or http://tinyurl.com/lur784


You'll excuse my skepticism about all these claims about how anyone can 
program, how easy it is to teach the fundamentals of Turing Machines and 
functional programming to anybody at all. Prove it. Where are your peer-
reviewed studies demonstrating such successes on randomly chosen people, 
not self-selected motivated, higher-than-average intelligence students?

In the real world, human beings are prone to serious cognitive biases and 
errors. Our brains are buggy. Take any list of reasoning fallacies, and 
you'll find the majority of people have difficulty avoid them. The first 
struggle is to get them to even accept that they *are* fallacies, but 
even once they have intellectually accepted it, getting them to live up 
to that knowledge in practice is much, much harder.

In fact I'd go further and say that *every single person*, no matter how 
intelligent and well-educated, will fall for cognitive biases and 
fallacious reasoning on a regular basis.

http://en.wikipedia.org/wiki/Cognitive_bias
http://en.wikipedia.org/wiki/Fallacy




-- 
Steven


From lie.1296 at gmail.com  Thu Jul  9 13:30:02 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 17:30:02 GMT
Subject: Cleaning up after failing to contructing objects
In-Reply-To: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
Message-ID: <uOp5m.3783$ze1.731@news-server.bigpond.net.au>

brasse wrote:
> Hello!
> I have been thinking about how write exception safe constructors in
> Python. By exception safe I mean a constructor that does not leak
> resources when an exception is raised within it. The following is an
> example of one possible way to do it:

First, your automatic cleaning Bar() silently pass an unitialized Bar()
into the calling code. When a code fails, it should fail as loud as
possible. Bar() should raises an Exception and the calling code should
turn into something like:

try:
    bar = Bar()
except Exception, e:
    print 'bar failed to construct'

And about the cleaning up, how about:

class CleanWrap(object):
    def __init__(self, cls, cleanup):
        self.cls = cls
        self.cleanup = cleanup
    def __call__(self, *args, **kargs):
        try:
            return self.cls(*args, **kargs)
        except:
            self.cleanup()
            raise

class Bar(object):
    def __init__(self):
        CleanWrappedFoo = CleanWrap(Foo, self.close)
        self.a = CleanWrappedFoo('a')
        self.b = CleanWrappedFoo('b', fail=True)
    def close(self):
        if hasattr(self, 'a'):
            self.a.close()
        if hasattr(self, 'b'):
            self.b.close()

try:
    bar = Bar()
except Exception, e:
    print 'Bar() failed to construct'

==========
My next attempt is pretty neat, using a totally different approach, see
the docstring for details:

class Foo1(object):
    def __init__(self, name, fail=False):
        self.name = name
        cls_name = self.__class__.__name__
        if not fail:
            print '%s.__init__(%s)' % (cls_name, self.name)
        else:
            print '%s.__init__(%s), FAIL' % (cls_name, self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)

class Foo2(object):
    def __init__(self, name, fail=False):
        self.name = name
        cls_name = self.__class__.__name__
        if not fail:
            print '%s.__init__(%s)' % (cls_name, self.name)
        else:
            print '%s.__init__(%s), FAIL' % (cls_name, self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)


class CleanList(object):
    ''' Each CleanList() instance is rigged so that if exceptions happen
        in the same CleanList() instance's wrapped class, all objects
        created from the wrapped classes in the same CleanList()
        instance will be cleaned (see "Usage" for much better
        explanation).

        Usage:
        >>> cleaner = CleanList()
        >>> othercleaner = CleanList()
        >>> F = cleaner(F, F.close)
        >>> G = cleaner(G, G.close)
        >>> H = othercleaner(H, H.close)
        >>> a = F()
        >>> b = F()
        >>> c = G()
        >>> d = H()
        >>> cleaner.cleanall()

        cleaner.cleanall() will clean a, b, and c but not d
        exceptions in (F|G|H).__init__ will trigger
        cleaner.cleanall()

        Can be subclassed if you want to override the conditions
        that determines the triggering of cleanups
    '''
    def wrap(self, cls):
        ''' Wrapper factory that customizes Wrapper's subclass
        '''
        class Wrapper(cls):
            ''' Wraps the class' __init__ with cleanup guard.
                Subclasses cls to simulate cls as close as possible
            '''

            # change __class__ to make printing prettier
            # e.g. Foo1.__init__ instead of Wrapper.__init__
            # probably should be removed
            # I'm not sure of the side effects of changing __class__
            __class__ = cls

            def __init__(self_in, *args, **kargs):
                try:
                    sup = super(Wrapper, self_in)
                    ret = sup.__init__(*args, **kargs)
                except:
                    self.cleanall()
                    raise
                else:
                    self.add_to_list(cls, self_in)
                    return ret
        return Wrapper

    def __init__(self):
        self.cleaners = {}

    def __call__(self, cls, cleanup):
        ''' wraps the class constructor '''
        # cleanup, []:
        # cleanup is the function called to clean
        # [] is the object list for that `cleanup` function
        # may not be the best data structure, but it works...
        self.cleaners[cls] = cleanup, []
        return self.wrap(cls)

    def cleanall(self):
        ''' clean all objects '''
        for cleaner, insts in self.cleaners.values():
            for inst in insts:
                cleaner(inst)

    def add_to_list(self, cls, inst):
        ''' add objects to the cleanup list '''
        self.cleaners[cls][1].append(inst)

class Bar(object):
    def __init__(self):
        clist = CleanList()
        otherclist = CleanList()
        CleanFoo1 = clist(Foo1, Foo1.close)
        CleanFoo2 = clist(Foo2, Foo2.close)
        OtherCleanFoo1 = otherclist(Foo1, Foo1.close)
        self.a = CleanFoo1('a')
        self.b = CleanFoo2('b')
        # self.c should not be close()ed
        self.c = OtherCleanFoo1('c')
        self.d = CleanFoo1('d', fail=True)
        self.e = CleanFoo2('e')

class Car(object):
    def __init__(self):
        Clean = CleanList()
        CleanFoo1 = Clean(Foo1, Foo1.close)
        CleanFoo2 = Clean(Foo2, Foo2.close)
        self.a = CleanFoo1('a')
        self.b = CleanFoo2('b')
        self.c = CleanFoo1('c')
        self.d = CleanFoo2('d')

try:
    bar = Car()
except Exception, e:
    print e
    print 'Car() failed to construct'
print
try:
    bar = Bar()
except Exception, e:
    print e
    print 'Bar() failed to construct'


From sebastian.schabe at gmx.de  Thu Jul  9 13:34:59 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Thu, 09 Jul 2009 19:34:59 +0200
Subject: Concatenating images (numpy arrays), but they look like HSV images
Message-ID: <4a5629ba$1@news.fhg.de>

Hello everybody,

I want to concatenate 2 numpy array which in fact are RGB images:

def concat_images(im1,im2):
   rows1 = im1.shape[0]
   rows2 = im2.shape[0]

   if rows1 < rows2:
     im1 = concatenate((im1,zeros((rows2-rows1,im1.shape[1],3), int)), 
axis=0)
   elif rows1 > rows2:
     im2 = concatenate((im2,zeros((rows1-rows2,im2.shape[1],3), int)), 
axis=0)

   return concatenate((im1,im2), axis=1)

It's all working fine, except that the images when showing with pylab 
are somewhat interpreted as HSV images as it looks. The function zeros() 
must be responsible for that circumstance, because when the arrays have 
the same shape and are concatenated they appear as horizontally 
concatenated images as I expected.

Can someone help me with that?

Thanks a lot,
Basti


From lie.1296 at gmail.com  Thu Jul  9 13:35:19 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 17:35:19 GMT
Subject: property using a classmethod
In-Reply-To: <4a55e8e0$0$8041$426a34cc@news.free.fr>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
	<4a55e8e0$0$8041$426a34cc@news.free.fr>
Message-ID: <rTp5m.3784$ze1.643@news-server.bigpond.net.au>

Bruno Desthuilliers wrote:
> Lie Ryan a ?crit :
>> Emanuele D'Arrigo wrote:
> (snip)
>>> Ultimately all I want is a non-callable class-level attribute
>>> MyClass.myProperty that gives the result of MyClass.myClassMethod().
>>
>> This works like what you seem to want (it's ugly):
> 
> Ugly, indeed. And an extreme case of arbitrary overcomplexification too :-/
> 
> (snip rube goldberg code)
> 

Can't think of anything simpler than that without meddling with
descriptor. I'm not even sure descriptor can help here as it seems
descriptor needs an instance? (I've just skimmed it, so I may be wrong)

The ugliness of the code hints to two possible reasons:
- there should be a better way
- if there isn't an easier way, then something is wrong the class' design


From duane.kaufman at gmail.com  Thu Jul  9 13:36:50 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 10:36:50 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
Message-ID: <558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>

On Jul 9, 12:18?pm, Tim Harig <user... at ilthio.net> wrote:
> On 2009-07-09, TheSeeker <duane.kauf... at gmail.com> wrote:
>
> > Specifically, I have a WinForms application I will be wanting to
> > automate. Does anyone have some Python examples of driving Microsoft
> > UI Automation they could share with me to get me started? The
> > structure of the UI automation classes etc. seem quite convoluted, and
> > I am having difficulty getting my brain wrapped around it.
>
> If you find a way to work through the UI using the keyboard (tabs, etc);
> then, you can send it keyboard commands using WScript.WshShell.SendKeys():
>
> http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx

Thanks for the link.

Unfortunately, I need to be able to find out the contents of a few
text-boxes as well,
so SendKeys isn't all I need.

Thanks again,
Duane


From tjreedy at udel.edu  Thu Jul  9 13:40:01 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 09 Jul 2009 13:40:01 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <4A55F392.3080404@ieee.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
	<4A55F392.3080404@ieee.org>
Message-ID: <h35a1h$gus$1@ger.gmane.org>

Dave Angel wrote:
> m.reddy prasad reddy wrote:
>> can any one tell me how to write assembly language programs in 
>> python...if
>> no is there any other way to write the programs in python
>>
>> Reddi prasad reddy
>> ph.no:09958083797
>>
>>   
> Assembly language is a different programming language than Python.  You 
> can use both in the same process, much in the same way you can use C or 
> C++ with Python.  In fact, some of the system DLL's are written (partly) 
> in assembler, though mostly in C or C++.

It is possible that he meant how to write assembly *with* python.
Or how to translate python to assembly.

As it turns out, CPython translates Python to byte code and has a dis 
(assembly) module that produces very nice assembly code ;-)
So that is one answer to his question.

> You'll need to tell us what your real goal is.

Definitely.

tjr



From lie.1296 at gmail.com  Thu Jul  9 13:40:28 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 17:40:28 GMT
Subject: older pythons
In-Reply-To: <4a55e1fb$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
	<Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
	<4a55e1fb$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <gYp5m.3785$ze1.1005@news-server.bigpond.net.au>

superpollo wrote:
> Lie Ryan wrote:
>> superpollo wrote:
>>
>>> Lie Ryan wrote:
>>>
>>>
>>>> AFAIK, no major linux distributions have officially ported to python
>>>> 3.x.
>>>
>>> http://packages.debian.org/experimental/python3.1
>>>
>> Note the word "experimental"
> 
> i noticed. isn't experimental official? i thought it was...

Official as in "official release"?


From Scott.Daniels at Acm.Org  Thu Jul  9 13:40:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Thu, 09 Jul 2009 10:40:58 -0700
Subject: property using a classmethod
In-Reply-To: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
Message-ID: <3dKdndiWOZRutMvXnZ2dnUVZ_gFi4p2d@pdx.net>

Emanuele D'Arrigo wrote:
> class MyClass(object):
>     @classmethod
>     def myClassMethod(self):
>          print "ham"
>      myProperty = property(myClassMethod, None, None)
> 
> ... doesn't work and returns a TypeError: .... So, how do I do this?
> Ultimately all I want is a non-callable class-level attribute
> MyClass.myProperty that gives the result of MyClass.myClassMethod().

properties affect instances, and classes are instances of types.
What you want is a new metaclass:

     class MyType(type):
         @property
         def demo(class_):
             return class_.a + 3

     class MyClass(object):
         __metaclass__ = MyType
         a = 5

     print MyClass.a, MyClass.demo

--Scott David Daniels
Scott.Daniels at Acm.Org


From rhodri at wildebst.demon.co.uk  Thu Jul  9 13:41:59 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 09 Jul 2009 18:41:59 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
Message-ID: <op.uws939iha8ncjz@gnudebst>

On Thu, 09 Jul 2009 17:06:45 +0100, Tom Kermode <tkermode at gmail.com> wrote:

> Hi,
>
>    Do you know a good way to avoid running into this problem?  It
> makes sense to suggest not calling variables the same names as
> built-in functions, but that's hard for a new python programmer who
> doesn't already know what all the built-in functions are. Over time a
> programmer will learn which names to avoid, but it's a bit of a
> pitfall early on.

It's only really a pitfall if you try to use the built-in after you've
redefined it.  That's the thing to keep an eye open for.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Thu Jul  9 13:42:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 09 Jul 2009 19:42:56 +0200
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
	<m27hyi9jof.fsf@cs.uu.nl>
	<cafc471d-e1c3-4024-8090-898408415d8f@t13g2000yqt.googlegroups.com>
Message-ID: <m23a95ah27.fsf@cs.uu.nl>

>>>>> Lacrima <Lacrima.Maxim at gmail.com> (L) wrote:

>L> Thank you for really useful and detailed explanation. Now I can test
>L> my code using Emacs.
>L> But I think it works for me in a little bit different way.
>L> My file contains only the print 'hello world'.
>L> If I have no python shell running, then:
>L> a) C-c RET opens *Python Output* buffer without any output and with
>L> 'Shell command succeeded with no output' message at the bottom
>L> b) C-c C-c opens *Python Output* with appropriate 'hello world'
>L> message.

>L> Then I run python shell with C-c ! command. And:
>L> a) C-c RET opens *Python* buffer and prints 'hello world' in the
>L> python shell
>L> b) C-c C-c gives the same result.

Which version of python-mode.el do you have? (Variable py-version)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From usernet at ilthio.net  Thu Jul  9 13:45:13 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 09 Jul 2009 17:45:13 GMT
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
Message-ID: <J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>

On 2009-07-09, DuaneKaufman <duane.kaufman at gmail.com> wrote:
> On Jul 9, 12:18?pm, Tim Harig <user... at ilthio.net> wrote:
>> On 2009-07-09, TheSeeker <duane.kauf... at gmail.com> wrote:
>> > Specifically, I have a WinForms application I will be wanting to
>> > automate. Does anyone have some Python examples of driving Microsoft
>> > UI Automation they could share with me to get me started? The
>> > structure of the UI automation classes etc. seem quite convoluted, and
>> > I am having difficulty getting my brain wrapped around it.
>> If you find a way to work through the UI using the keyboard (tabs, etc);
>> then, you can send it keyboard commands using WScript.WshShell.SendKeys():
>> http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx
> Unfortunately, I need to be able to find out the contents of a few
> text-boxes as well,
> so SendKeys isn't all I need.

Then you will need some way to import your application as an object so that
you can gain access to the methods and properties directly.  Using
IronPython you should be able to access anyting in the GAC.  If you
register your UI componets then you should be able to access them.  If not,
or using cpython, you might be able to do something like:

http://msdn.microsoft.com/en-us/library/fh1h056h(VS.71).aspx

to get a mashalled COM object.


From black.linen99 at gmail.com  Thu Jul  9 13:46:47 2009
From: black.linen99 at gmail.com (Alex Rosslyn)
Date: Thu, 9 Jul 2009 10:46:47 -0700 (PDT)
Subject: Colour of output text
Message-ID: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>

Hi,

I would like to learn a way of changing the colour of a particular
part of the output text. I've tried the following:

import os
os.system("color 17")
print "This should be white on blue"

But that command changes the colour of ALL the text and the whole
background. What i'm trying to do is simple: Change a single part (A
letter, a word, a phrase) of the output text.

Is there a way of doing this?

Thanks in advance,

~~A.Rosslyn


From tjreedy at udel.edu  Thu Jul  9 13:49:36 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 09 Jul 2009 13:49:36 -0400
Subject: tkinter problem
In-Reply-To: <4a5615ba$0$95523$742ec2ed@news.sonic.net>
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>	<mailman.2863.1247095339.8015.python-list@python.org>	<4a5536d4$0$95520$742ec2ed@news.sonic.net>	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
Message-ID: <h35ajf$i71$1@ger.gmane.org>

Paul Simon wrote:
> "Peter Otten" <__peter__ at web.de> wrote in message 
> news:h3481q$d95$00$1 at news.t-online.com...
>> Paul Simon wrote:
>>

>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
>>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>> something from python.org and installed.  Not sure if it was tarball or
>>> zip file.
>> Zip or tar doesn't matter, you are installing "from source".
>>
>> Python has to find the necessary include files for tcl/tk. These are in
>> separate packages that you have to install before you invoke Python's
>> configure script.
>>
>> I don't know what they are called on your system -- look for tk-dev.rpm,
>> tcl-dev.rpm or similar.
>>
>> You may run into the same problem with other modules like readline.
>>
>> Peter
>>
> 
> Thank you Peter.  I understand what you are saying but don't know how to do 
> it.  Although I installed from source, I followed a "cookbook" recipe. 
> Could you tell me what files to execute, where they might be, and file 
> arguments?  I'm just ignorant, not stupid. ;-).

Is there a Mandriva list where you can ask such distribution-specific 
questions?



From usernet at ilthio.net  Thu Jul  9 13:53:12 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 09 Jul 2009 17:53:12 GMT
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
Message-ID: <c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com>

On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
> I would like to learn a way of changing the colour of a particular
> part of the output text. I've tried the following

http://catb.org/esr/faqs/smart-questions.html

> import os
> os.system("color 17")
> print "This should be white on blue"

I assume that you are on Windows?

> But that command changes the colour of ALL the text and the whole
> background. What i'm trying to do is simple: Change a single part (A
> letter, a word, a phrase) of the output text.

If you are on Windows, then there is an API accessing the Windows Console:

http://msdn.microsoft.com/en-us/library/ms682010(VS.85).aspx

On Unix operating systems this would be done through the curses interface:

http://docs.python.org/library/curses.html


From robert.kern at gmail.com  Thu Jul  9 14:08:08 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 09 Jul 2009 13:08:08 -0500
Subject: Concatenating images (numpy arrays), but they look like HSV images
In-Reply-To: <4a5629ba$1@news.fhg.de>
References: <4a5629ba$1@news.fhg.de>
Message-ID: <h35bma$m93$1@ger.gmane.org>

On 2009-07-09 12:34, Sebastian Schabe wrote:
> Hello everybody,
>
> I want to concatenate 2 numpy array which in fact are RGB images:
>
> def concat_images(im1,im2):
> rows1 = im1.shape[0]
> rows2 = im2.shape[0]
>
> if rows1 < rows2:
> im1 = concatenate((im1,zeros((rows2-rows1,im1.shape[1],3), int)), axis=0)
> elif rows1 > rows2:
> im2 = concatenate((im2,zeros((rows1-rows2,im2.shape[1],3), int)), axis=0)
>
> return concatenate((im1,im2), axis=1)
>
> It's all working fine, except that the images when showing with pylab
> are somewhat interpreted as HSV images as it looks. The function zeros()
> must be responsible for that circumstance, because when the arrays have
> the same shape and are concatenated they appear as horizontally
> concatenated images as I expected.
>
> Can someone help me with that?

Ask on the matplotlib mailing list.

   https://lists.sourceforge.net/lists/listinfo/matplotlib-users

Probably, you need to use zeros(..., dtype=uint8). When you use dtype=int, that 
will result in dtype=int arrays. I suspect that matplotlib is then interpreting 
that to mean that you want it to treat the input as scalar data (which it will 
pass through a colormap) rather than an RGB image.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From duane.kaufman at gmail.com  Thu Jul  9 14:09:03 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 11:09:03 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
Message-ID: <e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>

On Jul 9, 12:45?pm, Tim Harig <user... at ilthio.net> wrote:
> On 2009-07-09, DuaneKaufman <duane.kauf... at gmail.com> wrote:
>
> > On Jul 9, 12:18?pm, Tim Harig <user... at ilthio.net> wrote:
> >> On 2009-07-09, TheSeeker <duane.kauf... at gmail.com> wrote:
> >> > Specifically, I have a WinForms application I will be wanting to
> >> > automate. Does anyone have some Python examples of driving Microsoft
> >> > UI Automation they could share with me to get me started? The
> >> > structure of the UI automation classes etc. seem quite convoluted, and
> >> > I am having difficulty getting my brain wrapped around it.
> >> If you find a way to work through the UI using the keyboard (tabs, etc);
> >> then, you can send it keyboard commands using WScript.WshShell.SendKeys():
> >>http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx
> > Unfortunately, I need to be able to find out the contents of a few
> > text-boxes as well,
> > so SendKeys isn't all I need.
>
> Then you will need some way to import your application as an object so that
> you can gain access to the methods and properties directly. ?Using
> IronPython you should be able to access anyting in the GAC. ?If you
> register your UI componets then you should be able to access them. ?If not,
> or using cpython, you might be able to do something like:
>
> http://msdn.microsoft.com/en-us/library/fh1h056h(VS.71).aspx
>
> to get a mashalled COM object.

Thanks again Tim.

I believe I probably mis-communicated my requirements (or at least,
was not explicit enough)

The application I wish to interact with is not my own, but an ERP
system GUI front-end.

With MS utilities like UISpy and the like, I can 'see' the controls in
the application, but I
do not seem to be able to manipulate them programatically, and I
believe it us simply due
to my not understanding of the UI Automation API.

Hence, my request for example code to boot-strap myself.

Thanks,
Duane


From steve at REMOVE-THIS-cybersource.com.au  Thu Jul  9 14:10:16 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 09 Jul 2009 18:10:16 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
Message-ID: <00720d76$0$9710$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:

>> persistent idea "out there" that programming is a very accessible
>> skill, like cooking or gardening, anyone can do it, and even profit
>> from it, monetarily or otherwise, etc., and to some extent I am
> 
> Programming is not like any other human activity.

In practice? In principle? Programming in principle is not the same as it 
is performed in practice.

But in either case, programming requires both the logical reasoning of 
mathematics and the creativity of the arts. Funnily enough, 
mathematicians will tell you that mathematics requires the same, and so 
will the best artists. I think mathematicians, engineers, artists, even 
great chefs, will pour scorn on your claim that programming is not like 
any other human activity.


[...]
> He talks about how "when all is said and done, the only thing computers
> can do for us is to manipulate symbols and produce results of such
> manipulations" and he emphasises the "uninterpreted" nature of
> mechanical symbol manipulation, i.e. that the machine is doing it
> mindlessly.

"Manipulate symbols" is so abstract as to be pointless. By that 
reasoning, I can build a "computer" consisting of a box open at the top. 
I represent a symbol by an object (say, a helium-filled balloon, or a 
stone), instead of a pattern of bits. I manipulate the symbol by holding 
the object over the box and letting go. If it flies up into the sky, that 
represents the symbol "Love is War", if it falls into the box, it 
represents the symbol "Strength is Blue", and if it just floats there, it 
represents "Cheddar Cheese". This is a deterministic, analog computer 
which manipulates symbols. Great.

And utterly, utterly useless. So what is my computer lacking that real 
computers have? When you have answered that question, you'll see why 
Dijkstra's claim is under-specified.



> Dijkstra[1]: "It is true that the student that has never manipulated
> uninterpreted formulae quickly realizes that he is confronted with
> something totally unlike anything he has ever seen before. But
> fortunately, the rules of manipulation are in this case so few and
> simple that very soon thereafter he makes the exciting discovery that he
> is beginning to master the use of a tool that, in all its simplicity,
> gives him a power that far surpasses his wildest dreams." [1]

What is an uninterpreted formula? If you don't interpret it, how can you 
distinguish it from random noise?


>> but maybe this idea is not entirely true...  Maybe, to get past the
>> most amateurish level, one has to, one way or another, come
>> face-to-face with bits, compilers, algorithms, and all the rest that
>> real computer scientists learn about in their formal training...
>>
>> kj
> 
> If you're never exposed to that constellation of concepts that underpins
> "mechanical symbol manipulation" you are adrift in a sea ("c", ha ha) of
> abstractions.
> 
> However, if you /are/ exposed to the "so few and simple" rules of
> manipulation the gates (no pun intended) to the kingdom are thrown wide.


What nonsense. The keys to the kingdom are the abstractions.

Here's an exercise for you, if you dare. It's not that difficult to 
remove the abstraction from integer addition, to explain it in terms of 
bit manipulation. If you prefer, you can write a Turing Machine instead.

Now try doing the same thing for Quicksort. Don't worry, we'll wait.

Once you've done that, let's see you implement a practical, scalable, non-
toy webserver as a Turing Machine.

No, it's not the fundamental operations that open the doors to the 
kingdom. It's the abstractions. The history of computing is to gain more 
and more power by leveraging better and better abstractions.


 
> On Jul 8, 9:10 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:

>> There is some evidence that 30-60% of people simply cannot learn to
>> program, no matter how you teach them:
>>
>> http://www.codinghorror.com/blog/archives/000635.html
>> http://www.cs.mdx.ac.uk/research/PhDArea/saeed/
...
> I don't buy it:


I'm not entirely convinced myself. It's plausible -- not everyone has got 
what it takes to be musically talented, or a great athlete, or a skilled 
surgeon, or a charismatic leader. Why should programming be the one high-
level intellectual skill that everybody is good at? Seems mighty 
implausible to me.

But I'm not sure that the distribution of skill is *fundamentally* bi-
modal. Maybe it is, maybe it isn't.


> I believe strongly that any normal person can learn to
> program, to manipulate symbols to create formulae that guide the machine
> in its uninterpreted symbol manipulation.

Most people don't manipulate abstract symbols *at all* -- even something 
as simple as:

"if x is to z as half y is to twice z, then x is the same as ____ y"
(fill in the blank)

will perplex most people.


> I think that "first hump" people can become "second hump" people but
> that it requires teaching them the foundations first, not confronting
> them with such incredible novelties as "a = b" and saying in effect,
> "here you go buddy, sink or swim."

The weakness of the paper is not that "a=b" is a novelty, but that it's 
dangerously familiar. All their students will have already seen "a=b" in 
the context of many years of mathematics. But that's not what it means in 
this context. So the risk is, they will be interpreting the symbols "a=b" 
in terms of mathematical equality, and getting confused.


> Quoting Dijkstra again [1]: "Before we part, I would like to invite you
> to consider the following way of doing justice to computing's radical
> novelty in an introductory programming course.
> 
> "On the one hand, we teach what looks like the predicate calculus, but
> we do it very differently from the philosophers. In order to train the
> novice programmer in the manipulation of uninterpreted formulae, we
> teach it more as boolean algebra, familiarizing the student with all
> algebraic properties of the logical connectives. To further sever the
> links to intuition, we rename the values {true, false} of the boolean
> domain as {black, white}.

This is supposed to be a good thing?

Oh my. It must be nice in that ivory tower, never having to deal with 
anyone who hasn't already been winnowed by years of study and self-
selection before taking on a comp sci course.

I don't think Dijkstra would have taken that suggestion seriously if he 
had to teach school kids instead of college adults.


... 
> (Did you read that last paragraph and think, "Well how the heck else are
> you supposed to program a computer if not in a computer language?"?  If
> so, well, that is kind of my point.)

No. What I thought was, how the hell are you supposed to manipulate 
symbols without a language to describe what sort of manipulations you can 
do?


>> > Maybe, to
>> > get past the most amateurish level, one has to, one way or another,
>> > come face-to-face with bits, compilers, algorithms, and all the rest
>> > that real computer scientists learn about in their formal training...
>>
>> The "No True Scotsman" fallacy.
>>
>> There's nothing amateurish about building software applications that
>> work, with well-designed interfaces and a minimum of bugs, even if
>> you've never heard of Turing Machines.
>>
>> --
>> Steven
> 
> I beg to differ. I recall a conversation with a co-worker who had
> "learned" to program using PHP.  Another co-worker and I were trying to
> convince him that there was a good reason to differentiate between hash
> tables and arrays. He didn't even know that they were different
> "things".

I shall manfully resist the urge to make sarcastic comments about 
ignorant PHP developers, and instead refer you to my earlier reply to you 
about cognitive biases. For extra points, can you identify all the 
fallacious reasoning in that paragraph of yours?


> I remember telling him, "between the metal and the desktop there is
> nothing but layers of abstraction.  We use different names precisely
> because of different behaviours."

But those abstractions just get in the way, according to you. He should 
be programming in the bare metal, doing pure symbol manipulation without 
language.


> He made "well-designed interfaces", but "amateurish" is about the nicest
> thing I would have called him.

Well, perhaps this is a failure of his profession, in that there isn't 
enough specialisation. If he is skilled with making interfaces, and 
unskilled with programming the backend, then he should work where his 
strength lies, instead of being insulted by somebody who has an entirely 
unjustified opinion about what "real programming" is.

If programming is symbol manipulation, then you should remember that the 
user interface is also symbol manipulation, and it is a MUCH harder 
problem than databases, sorting, searching, and all the other problems 
you learn about in academia. The user interface has to communicate over a 
rich but noisy channel using multiple under-specified protocols to a 
couple of pounds of meat which processes information using buggy 
heuristics evolved over millions of years to find the ripe fruit, avoid 
being eaten, and have sex. If you think getting XML was hard, that's 
*nothing* compared to user interfaces.

The fact that even bad UIs work at all is a credit to the heuristics, 
bugs and all, in the meat.


> As for "a minimum of bugs"... sigh. The "minimum of bugs" is zero, if
> you derive your "uninterpreted formulae" /correctly/.

And the secret of getting rich on the stock market is to buy low, sell 
high. Very true, and very pointless. How do you derive the formula 
correctly?

Do you have an algorithm to do so? If so, how do you know that algorithm 
is correct?


> Deriving provably
> correct "programs" should be what computer science and computer
> education are all about

That's impossible. Not just impractical, or hard, or subject to hardware 
failures, but impossible.

I really shouldn't need to raise this to anyone with pretensions of being 
a Computer Scientist and not just a programmer, but... try proving an 
arbitrary program will *halt*.

If you can't do that, then what makes you think you can prove all useful, 
necessary programs are correct?



> Again with Dijkstra[3]: "The prime paradigma of the pragmatic designer
> is known as "poor man's induction", i.e. he believes in his design as
> long as "it works", i.e. until faced with evidence to the contrary. (He
> will then "fix the design".) 

Yes, that is the only way it can be.


> The scientific designer, however, believes
> in his design because he understands why it will work under all
> circumstances. 

Really? Under *all* circumstances?

Memory failures? Stray cosmic radiation flipping bits? Noise in the power 
supply?

What's that you say? "That's cheating, the software designer can't be 
expected to deal with the actual reality of computers!!! We work in an 
abstract realm where computers never run out of memory, swapping never 
occurs, and the floating point unit is always correct!"

Fail enough. I don't want to make it too hard for you.

Okay, so let's compare the mere "pragmatic designer" with his provisional 
expectation that his code is correct, and Dijkstra's "scientific 
designer". He understands his code is correct. Wonderful!

Er, *how exactly* does he reach that understanding?

He reasons about the logic of the program. Great! I can do that. See, 
here's a proof that binary search is correct. How easy this is.

Now try it for some non-trivial piece of code. Say, the Linux kernel. 
This may take a while...

What guarantee do we have that the scientific designer's reasoning was 
correct? I mean, sure he is convinced he has reasoned correctly, but he 
would, wouldn't he? If he was unsure, he'd keep reasoning (or ask for 
help), until he was sure. But being sure doesn't make him correct. It 
just makes him sure.

So how do you verify the verification?

And speaking of binary search:

[quote]
I was shocked to learn that the binary search program that Bentley PROVED 
CORRECT and SUBSEQUENTLY TESTED [emphasis added] in Chapter 5 of 
"Programming Pearls" contains a bug. Once I tell you what the it is, you 
will understand why it escaped detection for two decades.
[end quote]

http://northernplanets.blogspot.com/2006/07/nearly-all-binary-searches-
are-broken.html

or http://tinyurl.com/nco6yv

Perhaps the "scientific designer" should be a little less arrogant, and 
take note of the lesson of real science: all knowledge is provisional and 
subject to correction and falsification.

Which really makes the "scientific designer" just a slightly more clever 
and effective "pragmatic designer", doesn't it?


> The transition from pragmatic to scientific design would
> indeed be a drastic change within the computer industry."

Given Dijkstra's definition of "scientific design", it certainly would. 
It would be as drastic a change as the discovery of Immovable Objects and 
Irresistible Forces would be to engineering, or the invention of a 
Universal Solvent for chemistry, or any other impossibility. 


> "Obviously no errors" is the goal to strive for, and I am comfortable
> calling anyone an amateur who prefers "no obvious errors."

It's not a matter of preferring no obvious errors, as understanding the 
limitations of reality. You simply can't do better than no obvious errors 
(although of course you can do worse) -- the only question is what you 
call "obvious".



-- 
Steven


From Lacrima.Maxim at gmail.com  Thu Jul  9 14:22:46 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Thu, 9 Jul 2009 11:22:46 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
	<m27hyi9jof.fsf@cs.uu.nl>
	<cafc471d-e1c3-4024-8090-898408415d8f@t13g2000yqt.googlegroups.com>
	<m23a95ah27.fsf@cs.uu.nl>
Message-ID: <53aaa579-e69a-43c3-b297-10c6ea6ebf35@b15g2000yqd.googlegroups.com>

On Jul 9, 8:42?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Lacrima <Lacrima.Ma... at gmail.com> (L) wrote:
> >L> Thank you for really useful and detailed explanation. Now I can test
> >L> my code usingEmacs.
> >L> But I think it works for me in a little bit different way.
> >L> My file contains only the print 'hello world'.
> >L> If I have no python shell running, then:
> >L> a) C-c RET opens *Python Output* buffer without any output and with
> >L> 'Shell command succeeded with no output' message at the bottom
> >L> b) C-c C-c opens *Python Output* with appropriate 'hello world'
> >L> message.
> >L> Then I run python shell with C-c ! command. And:
> >L> a) C-c RET opens *Python* buffer and prints 'hello world' in the
> >L> python shell
> >L> b) C-c C-c gives the same result.
>
> Which version of python-mode.el do you have? (Variable py-version)
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

py-version's value is "5.1.0"

Also maybe the problem is because I use Emacs version 21.4.1. But I
can't change it to 22, because I access Emacs via SSH on some shared
hosting service.

With regards, Max.


From ptmcg at austin.rr.com  Thu Jul  9 14:29:12 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Thu, 9 Jul 2009 11:29:12 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
Message-ID: <d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com>

On Jul 9, 1:09?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
> The application I wish to interact with is not my own, but an ERP
> system GUI front-end.
>

I have used pywinauto to drive a Flash game running inside of an
Internet Explorer browser - that's pretty GUI!

-- Paul


From duane.kaufman at gmail.com  Thu Jul  9 14:50:45 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 11:50:45 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
	<d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com>
Message-ID: <ff67eeab-48d1-40a5-8870-666944c8c7f2@q11g2000yqi.googlegroups.com>

On Jul 9, 1:29?pm, Paul McGuire <pt... at austin.rr.com> wrote:
> On Jul 9, 1:09?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
>
> > The application I wish to interact with is not my own, but an ERP
> > system GUI front-end.
>
> I have used pywinauto to drive a Flash game running inside of an
> Internet Explorer browser - that's pretty GUI!
>
> -- Paul

Hi,

Could you share some code examples?

Thanks,
Duane (duanek (at) chorus (dot) net)


From fridrik at pyth.net  Thu Jul  9 14:57:47 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 18:57:47 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <op.uws939iha8ncjz@gnudebst>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
	<op.uws939iha8ncjz@gnudebst>
Message-ID: <9DBED98B-8B7A-45DC-9177-D3E97B878AAF@pyth.net>

Hi Rhodri,

> It's only really a pitfall if you try to use the built-in after you've
> redefined it.  That's the thing to keep an eye open for.

You're right, but in cases where you're editing a codebase which you  
didn't author entirely by yourself you may not be aware of that.

That said, if the codebase you're working on is structured (short,  
concise methods) you should be working with small, consumable scopes  
you can inhale in entirety before modifying.

Regards,
Fri?rik M?r

From dns4 at cornell.edu  Thu Jul  9 15:08:29 2009
From: dns4 at cornell.edu (David Smith)
Date: Thu, 09 Jul 2009 15:08:29 -0400
Subject: tkinter problem
In-Reply-To: <4a5615ba$0$95523$742ec2ed@news.sonic.net>
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
Message-ID: <h35f78$pts$1@ruby.cit.cornell.edu>

Paul Simon wrote:
> "Peter Otten" <__peter__ at web.de> wrote in message 
> news:h3481q$d95$00$1 at news.t-online.com...
>> Paul Simon wrote:
>>
>>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>>> news:mailman.2863.1247095339.8015.python-list at python.org...
>>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>>> I have the "tkinter" problem and need some assistance to straighten it
>>>> out.
>>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>>>>> "step
>>>> 1" and cannot import "_tkinter." I do not have that file on my computer,
>>>> but
>>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>>> This python stuff is great, but the documentation frequently
>>>> feels like it is just a bit out of my grasp. I realize that all of this
>>>> is free but I understand the instructions on the web page to repair only
>>>> to the
>>>> point of confusion. I'm not an expert. How do I modify my python
>>>> configuration? Is there a file that needs to be edited? Which setup.py
>>>> file
>>>> do I use? Make? or python setup.py build and python setup.py install?
>>>> Thanks. I appreciate your help.
>>> - How did you install Python?
>>> - What Linux distro are you using?
>>>
>>> Cheers,
>>> Chris
>>> http://blog.rebertia.com
>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
>>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>> something from python.org and installed.  Not sure if it was tarball or
>>> zip file.
>> Zip or tar doesn't matter, you are installing "from source".
>>
>> Python has to find the necessary include files for tcl/tk. These are in
>> separate packages that you have to install before you invoke Python's
>> configure script.
>>
>> I don't know what they are called on your system -- look for tk-dev.rpm,
>> tcl-dev.rpm or similar.
>>
>> You may run into the same problem with other modules like readline.
>>
>> Peter
>>
> 
> Thank you Peter.  I understand what you are saying but don't know how to do 
> it.  Although I installed from source, I followed a "cookbook" recipe. 
> Could you tell me what files to execute, where they might be, and file 
> arguments?  I'm just ignorant, not stupid. ;-).
> 
> Paul 
> 
> 

Just install the tkinter package from the Mandriva Linux Control
Center's Software Management system.  I just did it, doing a search for
tkinter brought it right up.  All done.

--David


From ethan at stoneleaf.us  Thu Jul  9 16:06:16 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 09 Jul 2009 13:06:16 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h33k3d$2uu$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
Message-ID: <4A564DB8.3050209@stoneleaf.us>

kj wrote:
> 
> My scientific code is jam-packed with assertions.  I can't count
> the number of times that one such lowly assertion saved me from a
> silent but potentially disastrous bug. 

Now imagine that asserts had been disabled for that run...

The issue is not "should you validate your inputs", the issue is "do you 
want your validation able to be turned off?"

~Ethan~


From sberry2a at gmail.com  Thu Jul  9 16:16:38 2009
From: sberry2a at gmail.com (Sean)
Date: Thu, 9 Jul 2009 13:16:38 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
Message-ID: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>

I have a huge list, 10,000,000+ items.  Each item is a dictionary with
fields used to sort the list.  When I have completed sorting I want to
grab a page of items, say 1,000 of them which I do easily by using
list_data[x:x+1000]

Now I want to add an additional key/value pair to each dictionary in
the list, incrementing them by 1 each time.  So, if I grabbed page 2
of the list I would get:

[{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
1002}, ...]

Any way to do that with list comprehension?  Any other good way to do
it besides iterating over the list?

Thanks


From sberry2a at gmail.com  Thu Jul  9 16:33:01 2009
From: sberry2a at gmail.com (Sean)
Date: Thu, 9 Jul 2009 13:33:01 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <a1dd02c8-ffee-4f3f-8788-9cabcb194a86@y10g2000prf.googlegroups.com>

On Jul 9, 1:16?pm, Sean <sberr... at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?
>
> Thanks

I was able to do this by doing the following:
page_data = [[start_position + 1 + n, x] for n, x in enumerate
(page_data)]

However, this creates a list of lists, each containing an int and a
dictionary.  I wanted to add it directly to the dictionary.  I can add
the key position to the dictionary when the data is created, but how
would I assign the value in a list comprehension?



From tn.pablo at gmail.com  Thu Jul  9 16:38:16 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 9 Jul 2009 15:38:16 -0500
Subject: Best way to add a "position" value to each item in a list
In-Reply-To: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <fdd00b510907091338y5838da5ap3edfa8545c357bc@mail.gmail.com>

Howdy,

On Thu, Jul 9, 2009 at 15:16, Sean<sberry2a at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>

I don't get it, what do you increment by one, the value of a given key
or the number of key/value pairs?  Also, if  the 'position' key is the
index of the item in the list, then I don't understand what you mean
by 'page'.  Could you tell us about the structure of these
dictionaries?

> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?
>
> Thanks
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Pablo Torres N.


From ptmcg at austin.rr.com  Thu Jul  9 16:41:17 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Thu, 9 Jul 2009 13:41:17 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
	<d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com> 
	<ff67eeab-48d1-40a5-8870-666944c8c7f2@q11g2000yqi.googlegroups.com>
Message-ID: <d6bc18b8-f74e-40cb-ba9f-1be8386f2fc6@s31g2000yqs.googlegroups.com>

On Jul 9, 1:50?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
> > I have used pywinauto to drive a Flash game running inside of an
> > Internet Explorer browser - that's pretty GUI!
>
> > -- Paul
>
> Hi,
>
> Could you share some code examples?
>
> Thanks,
> Duane (duanek (at) chorus (dot) net)

I just went on a brief fishing expedition through two disk backups,
and no luck.  I guess it's been a while since I worked on this.

The work I did was entirely graphical, which is to say, my script
interacted with the Flash program by using PIL to take image snapshots
of the window, and then sifting through the bitmap looking for the
status of a "time remaining" thermometer-style gauge in the game.
Then the script could click on X-Y coordinates within the window,
which would get picked up by the Flash game, and the script would
monitor the "time remaining" gauge some more, and so on.

I'm not sure how well pywinauto would work in allowing you to access
controls such as textboxes within a form.  I remember that I had to
access the IE window using a caption name, and then found the embedded
Flash program as an embedded control of some sort, again, I probably
needed to indicate that it was some sort of "Adobe.FlashWidget1"
object or something.

I may have another, older disk backup at home, I can look for it later
this evening.

-- Paul


From malaclypse2 at gmail.com  Thu Jul  9 16:49:22 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Thu, 9 Jul 2009 16:49:22 -0400
Subject: Best way to add a "position" value to each item in a list
In-Reply-To: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <16651e80907091349x409158b7sf62f7bbd0fb7c1a6@mail.gmail.com>

On Thu, Jul 9, 2009 at 4:16 PM, Sean<sberry2a at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?

Normally you wouldn't mutate the items in a list with a list
comprehension.  Instead, you would use a for loop, like this:

for idx,item in enumerate(my_list_of_dicts):
    item['position'] = idx

Is there a particular reason you want to do this with a list
comprehension?  Using a list comp means you're going to create an
extra copy of your 10 million item list, just so you can add a key to
each member, then (probably) throw away the original list.  It doesn't
seem like the right tool for the job here.

-- 
Jerry


From jcd at sdf.lonestar.org  Thu Jul  9 16:56:44 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Thu, 09 Jul 2009 16:56:44 -0400
Subject: tough-to-explain Python
In-Reply-To: <00720d76$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <1247173004.20204.0.camel@aalcdl07>

On Thu, 2009-07-09 at 18:10 +0000, Steven D'Aprano wrote:
> If programming is symbol manipulation, then you should remember that
> the 
> user interface is also symbol manipulation, and it is a MUCH harder 
> problem than databases, sorting, searching, and all the other
> problems 
> you learn about in academia. The user interface has to communicate
> over a 
> rich but noisy channel using multiple under-specified protocols to a 
> couple of pounds of meat which processes information using buggy 
> heuristics evolved over millions of years to find the ripe fruit,
> avoid 
> being eaten, and have sex. If you think getting XML was hard, that's 
> *nothing* compared to user interfaces.

+1 QOTW!  QOTM, even!






From sberry2a at gmail.com  Thu Jul  9 17:00:27 2009
From: sberry2a at gmail.com (Sean)
Date: Thu, 9 Jul 2009 14:00:27 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <58d94d82-3482-4429-9632-3255d2a85295@12g2000pri.googlegroups.com>

On Jul 9, 1:16?pm, Sean <sberr... at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?
>
> Thanks

I was able to do this by doing the following:
page_data = [[start_position + 1 + n, x] for n, x in enumerate
(page_data)]

However, this creates a list of lists, each containing an int and a
dictionary.  I wanted to add it directly to the dictionary.  I can add
the key position to the dictionary when the data is created, but how
would I assign the value in a list comprehension?



From pavlovevidence at gmail.com  Thu Jul  9 17:03:13 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 9 Jul 2009 14:03:13 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <1bf2ab02-2a84-41a2-8156-9ec3ac7301c4@t13g2000yqt.googlegroups.com>

On Jul 9, 1:16?pm, Sean <sberr... at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?


Not really, but if you want to avoid the delay in setting the
dictionary elements (I'm guessing that is why you don't want to
iterate over the list--and parenthetically it's not iterating over the
list but adding dictionary items that is driving the time, and that
cost is unavoidable), you should consider adding the position elements
on demand.  That is, instead of running a big loop once to add
position to all ten million elements, just run the loop on individual
pages.

def get_page(start,end):
    page = list_data[start:end]
    for i,item in enumerate(page):
        page['position'] = start+i
    return page


That might not work depending on what you are doing but you should
consider it.


Carl Banks


From torriem at gmail.com  Thu Jul  9 17:09:13 2009
From: torriem at gmail.com (Michael Torrie)
Date: Thu, 09 Jul 2009 15:09:13 -0600
Subject: Examples of Python driven Microsoft UI Automation wanted
In-Reply-To: <e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
Message-ID: <4A565C79.4020501@gmail.com>

DuaneKaufman wrote:
> With MS utilities like UISpy and the like, I can 'see' the controls in
> the application, but I
> do not seem to be able to manipulate them programatically, and I
> believe it us simply due
> to my not understanding of the UI Automation API.

You're probably better off using a free app like AutoIt3 rather than
roll your own.  AutoIt's scripting language isn't as nice as Python, but
it does the job and it turing-complete.

http://www.autoitscript.com/autoit3/


From thebrasse at gmail.com  Thu Jul  9 17:10:02 2009
From: thebrasse at gmail.com (=?ISO-8859-1?Q?Mattias_Br=E4ndstr=F6m?=)
Date: Thu, 9 Jul 2009 14:10:02 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<uOp5m.3783$ze1.731@news-server.bigpond.net.au>
Message-ID: <42fbcee1-61b2-4ba8-a50a-39c9c0d2fe9c@k19g2000yqn.googlegroups.com>

On Jul 9, 7:30?pm, Lie Ryan <lie.1... at gmail.com> wrote:
> brasse wrote:
> > Hello!
> > I have been thinking about how write exception safe constructors in
> > Python. By exception safe I mean a constructor that does not leak
> > resources when an exception is raised within it. The following is an
> > example of one possible way to do it:
>
> First, your automatic cleaning Bar() silently pass an unitialized Bar()
> into the calling code. When a code fails, it should fail as loud as
> possible. Bar() should raises an Exception and the calling code should
> turn into something like:
>
> try:
> ? ? bar = Bar()
> except Exception, e:
> ? ? print 'bar failed to construct'
>

I know, I missed that little detail. :-)

> And about the cleaning up, how about:
>
> class CleanWrap(object):
> ? ? def __init__(self, cls, cleanup):
> ? ? ? ? self.cls = cls
> ? ? ? ? self.cleanup = cleanup
> ? ? def __call__(self, *args, **kargs):
> ? ? ? ? try:
> ? ? ? ? ? ? return self.cls(*args, **kargs)
> ? ? ? ? except:
> ? ? ? ? ? ? self.cleanup()
> ? ? ? ? ? ? raise
>
> class Bar(object):
> ? ? def __init__(self):
> ? ? ? ? CleanWrappedFoo = CleanWrap(Foo, self.close)
> ? ? ? ? self.a = CleanWrappedFoo('a')
> ? ? ? ? self.b = CleanWrappedFoo('b', fail=True)
> ? ? def close(self):
> ? ? ? ? if hasattr(self, 'a'):
> ? ? ? ? ? ? self.a.close()
> ? ? ? ? if hasattr(self, 'b'):
> ? ? ? ? ? ? self.b.close()
>

I think this example adds about as much overhead as my original
example with the try block. Ideally I would like to be able to write
my classes in the most straight forward manner possible. In my mind
that would be something like a naive constructor and a close/dispose
method:

def __init__(self):
    self.a = Foo()
    self.b = Bar()

def close(self):
    self.a.close()
    self.b.close()

See my other post (the one with the decorator named safe) in this
thread for an experiment I thought was promising for a while. However
there are some some use cases it has to cover to be useful:

(1) References to objects owned by someone else
def __init__(self, some_resource):
    self.not_my_responsibility = some_resource
    self.a = Foo()
    # If Foo.__init__ raises an exception self.not_my responsibility
should not be closed.

(2) Local objects
def __init__(self):
    x = Bar()
    self.a = Foo(x)
    # If Foo.__init__ raises an exception x should also be closed.

So far I have not been able to find any good solutions for (at least)
case 1. I'll give it a few more days, but I'm not  that hopeful. I
think that I will end up writing my classes very much like Bar in my
original post. If someone has any ideas for how to solve my two use
cases above with my decorator based approach I would really like to
hear them!

:.:: mattias


From torriem at gmail.com  Thu Jul  9 17:12:40 2009
From: torriem at gmail.com (Michael Torrie)
Date: Thu, 09 Jul 2009 15:12:40 -0600
Subject: Examples of Python driven Microsoft UI Automation wanted
In-Reply-To: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
Message-ID: <4A565D48.2060608@gmail.com>

TheSeeker wrote:
> Alternatives to Microsoft's UI Automation are welcome too, but I have
> tried using winguiauto and watsup (along with AutoIt), and there seems
> to be severe limitations when using these tools with WinForm
> applications.

http://www.autoitscript.com/forum/index.php?showtopic=96752 -- looks
like recent betas have much better support for WinForms, at least from
the change list.




From helvinlui at gmail.com  Thu Jul  9 17:19:23 2009
From: helvinlui at gmail.com (Helvin)
Date: Thu, 9 Jul 2009 14:19:23 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
	<mailman.2902.1247154895.8015.python-list@python.org>
Message-ID: <88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>

On Jul 10, 3:54?am, Robert Kern <robert.k... at gmail.com> wrote:
> On 2009-07-09 01:27, Helvin wrote:
>
>
>
>
>
> > On Jul 9, 11:29 am, Robert Kern<robert.k... at gmail.com> ?wrote:
> >> On 2009-07-08 18:10, Helvin wrote:
>
> >>> Thanks for the fast replies! I will look into how to use VTK now.
> >>> Where would I find VTK's explicit support for PyQt?
> >> Wrapping/Python/vtk/qt4/ in the VTK sources.
>
> >>> Because I have installed VTK (using its installer) and pyVTK (using
> >>> its setup.py file), but how do I actually use it in my code? According
> >>> to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
> >>> I have tried 'import vtk', but python can't find the vtk module.
> >> Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
> >> just a library for manipulating VTK files. The VTK Python bindings are part of
> >> VTK's distribution itself. Exactly how did you install VTK? Did you compile it
> >> yourself?
>
> > You mean, when I download VTK, the VTK Python bindings come with it?
> > I downloaded VTK from:http://vtk.org/files/release/5.4/
>
> Exactly which file did you download? I don't think the vtk-5.4.x-win32.exe
> installers have the Python bindings. You will need to build VTK from sources.
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
> ? that is made terrible by our own mad attempt to interpret it as though it had
> ? an underlying truth."
> ? ?-- Umberto Eco

Yes, I think you are right. I did initially use the windows installer.
I didn't know that it did't have python bindings. I thought that if I
had pyVTK, then it would work. But it didn't. I am now building VTK
with sources according to this EXCELLENT tutorial that I have somehow
come across, at:
http://www-viz.tamu.edu/courses/viza658/08spring/tutorials/WinVTKInstall.html

It's for Windows XP, and I am on Vista, but I hope it will work. I
have worked my way through most of it now.

Thanks Robert!
Helvin


From mail.to.daniel.platz at googlemail.com  Thu Jul  9 18:03:36 2009
From: mail.to.daniel.platz at googlemail.com (tt-industries)
Date: Thu, 9 Jul 2009 15:03:36 -0700 (PDT)
Subject: Package for fast plotting of many data points in Python?
Message-ID: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>

Hi,

I am programming a oscilloscope module in Python. For this reason, I
want to plot very many data points as fast as possible. This can be
more than 100 000 at once. So far I have been using the ploting module
of wxPython. However, it becomes unstable for more than 25000 points.
Can someone recommend me a faster plotting library? It would be really
cool if one could embed this in wxPython. If someone has an idea I
would be very glad about answer.

With kind regards,

Daniel


From duane.kaufman at gmail.com  Thu Jul  9 18:10:10 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 15:10:10 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<mailman.2916.1247173965.8015.python-list@python.org>
Message-ID: <4be34b72-0961-4031-b943-82c9e7c95577@24g2000yqm.googlegroups.com>

On Jul 9, 4:12?pm, Michael Torrie <torr... at gmail.com> wrote:
> TheSeeker wrote:
> > Alternatives to Microsoft's UI Automation are welcome too, but I have
> > tried using winguiauto and watsup (along with AutoIt), and there seems
> > to be severe limitations when using these tools with WinForm
> > applications.
>
> http://www.autoitscript.com/forum/index.php?showtopic=96752-- looks
> like recent betas have much better support for WinForms, at least from
> the change list.

Hi,

Thanks for the information. Boy, you are away from a utility for a
couple of
weeks, and it starts growing things one needs!

Unfortunately, while it looks like AutoIt is gaining the ability to
'see' WinForms controls,
this beta doesn't seem to be able to retrieve the text say, in a
TextBox. Darn.

Thanks,
Duane


From stef.mientki at gmail.com  Thu Jul  9 18:26:09 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Fri, 10 Jul 2009 00:26:09 +0200
Subject: Package for fast plotting of many data points in Python?
In-Reply-To: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <4A566E81.5040503@gmail.com>

tt-industries wrote:
> Hi,
>
> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once.
At once is impossible ;-)
>  So far I have been using the ploting module
> of wxPython.
which plotting module ?
>  However, it becomes unstable for more than 25000 points.
>   
again what do you mean: 25000 points per ?
25000 points on a 1600 pixel width screen ?

Please try to be somewhat more specific.
cheers,
Stef
> Can someone recommend me a faster plotting library? It would be really
> cool if one could embed this in wxPython. If someone has an idea I
> would be very glad about answer.
>
> With kind regards,
>
> Daniel
>   



From tn.pablo at gmail.com  Thu Jul  9 18:49:48 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 9 Jul 2009 17:49:48 -0500
Subject: can i write a assemly language programs in python
In-Reply-To: <h35a1h$gus$1@ger.gmane.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com> 
	<4A55F392.3080404@ieee.org> <h35a1h$gus$1@ger.gmane.org>
Message-ID: <fdd00b510907091549p1416e82le07640632d168994@mail.gmail.com>

Or maybe he meant if you can have both Python and assembler code in
the same source file, but I haven't heard of it.  If what you are
trying to do is write a faster version of some part of your code, try
SWIG: http://www.swig.org/

Playing the guessing game is a time sink, and since nobody has done it
so far, I will: OP, please read
http://www.mikeash.com/getting_answers.html and
http://catb.org/esr/faqs/smart-questions.html

On Thu, Jul 9, 2009 at 12:40, Terry Reedy<tjreedy at udel.edu> wrote:
> Dave Angel wrote:
>>
>> m.reddy prasad reddy wrote:
>>>
>>> can any one tell me how to write assembly language programs in
>>> python...if
>>> no is there any other way to write the programs in python
>>>
>>> Reddi prasad reddy
>>> ph.no:09958083797
>>>
>>>
>>
>> Assembly language is a different programming language than Python. ?You
>> can use both in the same process, much in the same way you can use C or C++
>> with Python. ?In fact, some of the system DLL's are written (partly) in
>> assembler, though mostly in C or C++.
>
> It is possible that he meant how to write assembly *with* python.
> Or how to translate python to assembly.
>
> As it turns out, CPython translates Python to byte code and has a dis
> (assembly) module that produces very nice assembly code ;-)
> So that is one answer to his question.
>
>> You'll need to tell us what your real goal is.
>
> Definitely.
>
> tjr
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Pablo Torres N.


From milesck at umich.edu  Thu Jul  9 19:28:11 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Thu, 9 Jul 2009 19:28:11 -0400
Subject: Catching control-C
In-Reply-To: <n8m5m.3759$ze1.2493@news-server.bigpond.net.au>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
	<n8m5m.3759$ze1.2493@news-server.bigpond.net.au>
Message-ID: <4F69EE56-6911-400D-B324-4F6CE3E789CF@umich.edu>

On Jul 9, 2009, at 9:20 AM, Lie Ryan wrote:

> Michael Mossey wrote:
>> I want to understand better what the "secret" is to responding to a
>> ctrl-C in any shape or form.
>
> Are you asking: "when would the python interpreter process
> KeyboardInterrupt?"
> ...
> In single threaded python program, the currently running thread is
> always the main thread (which can handle KeyboardInterrupt). I believe
> SIGINT is checked at every ticks. But SIGINT cannot interrupt atomic
> operations (i.e. it cannot interrupt long operations that takes a  
> single
> tick).

Some otherwise atomic single-bytecode operations (like large integer  
arithmetic) do manual checks for whether signals were raised (though  
that won't help at all if the operation isn't on the main thread).

> I believe a tick in python is equivalent to a single bytecode, but
> please correct me if I'm wrong.

Not all opcodes qualify as a tick.  In general, those opcodes that  
cause control to remain in the eval loop (and not make calls to other  
Python or C functions) don't qualify as ticks (but there are  
exceptions, e.g. so that while True: pass is interruptible).  In  
Python/ceval.c: PyEval_EvalFrameEx(), those opcodes that don't end in  
goto fast_next_opcode are ticks.

Please correct me if _I'm_ wrong! :)
-Miles



From sajmikins at gmail.com  Thu Jul  9 19:38:18 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 9 Jul 2009 19:38:18 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <50f98a4c0907091638u6ad23eaeo779a333a46860dc8@mail.gmail.com>

On Thu, Jul 9, 2009 at 3:17 AM, m.reddy prasad reddy<reddy.mrp at gmail.com> wrote:
>
> can any one tell me how to write assembly language programs in python...if
> no is there any other way to write the programs in python
>
> Reddi prasad reddy
> ph.no:09958083797
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>

Examine CorePy http://www.corepy.org

"CorePy is a complete system for developing machine-level programs in
Python. CorePy lets developers build and execute assembly-level
programs interactively from the Python command prompt, embed them
directly in Python applications, or export them to standard assembly
languages."

HTH,
~Simon


From xavier.benech at t-immersion.com  Thu Jul  9 19:39:07 2009
From: xavier.benech at t-immersion.com (=?ISO-8859-1?Q?Xavier_B=E9nech?=)
Date: Fri, 10 Jul 2009 01:39:07 +0200
Subject: sys.exit() and PyRun_SimpleFileExFlags()
Message-ID: <4A567F9B.80108@t-immersion.com>

Hi,

There is a behaviour I do not understand of PyRun_SimpleFileExFlags(), 
normally when it executes a python script containing a sys.exit(), it 
results by ending the calling application.

I have got this behaviour with PyRun_SimpleFileExFlags() when I call it 
from the main thread of a GUI application (so I use PyRun_FileExFlags() 
in this case).

But in another application when it is called 
(PyRun_SimpleFileExFlags())) from a working thread (not the main one) of 
a console application, everything just go fine without exiting the 
application nor the thread. It returns the exit code specified in 
sys.exit() just fine.

Last things, I am working on Windows. And for the story, I started to 
make a small function to wrap some embedded python script call using the 
simple way with PyRun_SimpleFileExFlags() for the second application, 
but when I integrate it in the first one (with GUI) got some problems 
(:)) so I redo things with a cleaner PyRun_FileExFlags() call.

So, my question is: why do I have different behaviour of 
PyRun_SimpleFileExFlags() in this two cases?

Regards,
Xavier Benech.



From bearophileHUGS at lycos.com  Thu Jul  9 19:49:10 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 9 Jul 2009 16:49:10 -0700 (PDT)
Subject: can i write a assemly language programs in python
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com> 
	<mailman.2921.1247182700.8015.python-list@python.org>
Message-ID: <4d8af709-e4c1-431e-9a43-7f0f0dd8f1a6@j32g2000yqh.googlegroups.com>

Simon Forman:
> Examine CorePyhttp://www.corepy.org
>
> "CorePy is a complete system for developing machine-level programs in
> Python. CorePy lets developers build and execute assembly-level
> programs interactively from the Python command prompt, embed them
> directly in Python applications, or export them to standard assembly
> languages."

I have never used CorePy yet, but it's an awesome project ^_^
With some care and work even Python programs can get fast enough :-)

Bye,
bearophile


From clp2 at rebertia.com  Thu Jul  9 19:54:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 16:54:23 -0700
Subject: Package for fast plotting of many data points in Python?
In-Reply-To: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <50697b2c0907091654l188ea9c1v6b568fdf1dc5e89@mail.gmail.com>

On Thu, Jul 9, 2009 at 3:03 PM,
tt-industries<mail.to.daniel.platz at googlemail.com> wrote:
> Hi,
>
> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once. So far I have been using the ploting module
> of wxPython. However, it becomes unstable for more than 25000 points.
> Can someone recommend me a faster plotting library? It would be really
> cool if one could embed this in wxPython. If someone has an idea I
> would be very glad about answer.

Don't know how fast it is or how well it integrates, but matplotlib is
probably worth considering:
http://matplotlib.sourceforge.net/

Cheers,
Chris
-- 
http://blog.rebertia.com


From sajmikins at gmail.com  Thu Jul  9 20:01:47 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 9 Jul 2009 20:01:47 -0400
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <50f98a4c0907091701q660fec7cxfe75315a4e72575b@mail.gmail.com>

On Thu, Jul 9, 2009 at 9:42 AM, Nick<nleioatt at gmail.com> wrote:
<snip>
> ? ?fields = line.split()
> ? ?for i in range(len(fields)):
> ? ? ? ?fields[i] = float(fields[i])


instead of the above code you could say:

fields = [float(n) for n in in line.split()]

Have fun getting back into python! :]  (A lot has changed in the last few years)
HTH,
~Simon


From http  Thu Jul  9 20:22:06 2009
From: http (Paul Rubin)
Date: 09 Jul 2009 17:22:06 -0700
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <7xab3d9ykx.fsf@ruckus.brouhaha.com>

Nick <nleioatt at gmail.com> writes:
> text = file.readlines()
> len = len(text)
> fields = text[1].split()

Is that intended to split the first line of the file?  Remember
that arrays in python begin at index 0.


From marty.musatov at gmail.com  Thu Jul  9 21:03:31 2009
From: marty.musatov at gmail.com (Musatov)
Date: Thu, 9 Jul 2009 18:03:31 -0700 (PDT)
Subject: AP  -- MeAmI.org Paces Google
Message-ID: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>

Los Angeles (AP) --MeAmI.org now has users in 50 countries following
its adopted use in Pakistan.  The search engine has grown in
popularity 10,000 fold following its Beta test launch three months ago
in April, 2009. Supporters of the site claim it is better than rival
Google upon which platform it is based. Controversy arose after
MeAmI.org search code allowed users to search other users Google
results with no advertising. "It is truly an innovative thing we are
doing," said Founder and CEO, Martin Musatov. "Letting users search
the results of other Google users immediately results in a level of
accuracy and relevance above and beyond Google." Google changed their
API following the launch or MeAmI.org and explored the possibility of
blocking site access from MeAmI.org to Google search results but was
unable to do so. Critics of MeAmI.org say what it is doing is
tantamount to intellectual theft. When asked about this topper Musatov
exclaimed, "The Internet was made for people, not companies." An
analyst at Goldman Sachs says, requesting to remain anonymous,
"MeAmI.org has a strong presence in promoting itself as a vehicle for
global activism and to tell you the truth, this makes it much more
likely an acquisition target than potential intellectual property
violator." Google could not be reached for comment.


From ldo at geek-central.gen.new_zealand  Thu Jul  9 21:05:01 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Fri, 10 Jul 2009 13:05:01 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
Message-ID: <h3643t$3f5$6@lust.ihug.co.nz>

In message <h3291j$mfu$1 at reader1.panix.com>, kj wrote:

> .., Lundh writes:
> 
>   Assignment statements modify namespaces, not objects.

<counterexample>

    >>> a = [3]
    >>> b = a

These may indeed modify a namespace, not any object. However:

    >>> a[:] = [4]
    >>> a
    [4]
    >>> b
    [4]

What change has happened to the namespace in this case? None. Yet an object 
has changed.

</counterexample>



From ben+python at benfinney.id.au  Thu Jul  9 21:06:34 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 10 Jul 2009 11:06:34 +1000
Subject: Running a script to build docs from setup.py
References: <20090709173343.1784710d@realh.co.uk>
Message-ID: <87fxd5ny79.fsf@benfinney.id.au>

Tony Houghton <h at realh.co.uk> writes:

> I've looked through the manual but I can't find any hooks in distutils
> for generating files at install time other than extension modules and
> .pyc files. Should I just run the script from somewhere in my setup.py
> before calling distutils' setup function?

Indirectly related: Ian Bicking's article on using Python's ?setup.py?
as a ?Makefile? replacement:

    <URL:http://blog.ianbicking.org/pythons-makefile.html>

If one is writing a ?setup.py? anyway, I think it makes sense to use
that as the build program for the whole project if possible. Good
hunting!

-- 
 \     ?I have an answering machine in my car. It says, ?I'm home now. |
  `\  But leave a message and I'll call when I'm out.?? ?Steven Wright |
_o__)                                                                  |
Ben Finney


From scriber17 at aol.com  Thu Jul  9 21:07:55 2009
From: scriber17 at aol.com (The Masked Logician)
Date: Thu, 9 Jul 2009 18:07:55 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <8bbed30b-53e5-4558-8e50-fbc395221915@y10g2000prf.googlegroups.com>

On Jul 9, 6:03?pm, Musatov <marty.musa... at gmail.com> wrote:
> Los Angeles (AP) -- MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan. The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
> the results of other Google users immediately results in a level of
> accuracy and relevance above and beyond Google." Google changed their
> API following the launch or MeAmI.org and explored the possibility of
> blocking site access from MeAmI.org to Google search results but was
> unable to do so. Critics of MeAmI.org say what it is doing is
> tantamount to intellectual theft. When asked about this topper Musatov
> exclaimed, "The Internet was made for people, not companies." An
> analyst at Goldman Sachs says, requesting to remain anonymous,
> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> global activism and to tell you the truth, this makes it much more
> likely an acquisition target than potential intellectual property
> violator." Google could not be reached for comment.

Wow.


From ben+python at benfinney.id.au  Thu Jul  9 21:11:26 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 10 Jul 2009 11:11:26 +1000
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <87bpntnxz5.fsf@benfinney.id.au>

tt-industries <mail.to.daniel.platz at googlemail.com> writes:

> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once.

I think you will find good results using Numpy for your arrays of data
<URL:http://numpy.scipy.org/> and Matplotlib to plot those arrays
<URL:http://matplotlib.sourceforge.net/>.

-- 
 \        ?Ubi dubium, ibi libertas.? (?Where there is doubt, there is |
  `\                                                        freedom.?) |
_o__)                                                                  |
Ben Finney


From roy at panix.com  Thu Jul  9 21:16:09 2009
From: roy at panix.com (Roy Smith)
Date: Thu, 09 Jul 2009 21:16:09 -0400
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <roy-D93967.21160909072009@news.panix.com>

In article 
<0734dc45-d8a0-4f28-b945-f9e179f30f5c at h11g2000yqb.googlegroups.com>,
 tt-industries <mail.to.daniel.platz at googlemail.com> wrote:

> I am programming a oscilloscope module in Python.

Sigh.  I guess I'm showing my age, but I still can't get used to the idea 
that the right tool to build an oscilloscope is no longer a soldering iron.


From bcb at undisclosedlocation.net  Thu Jul  9 21:18:23 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Thu, 9 Jul 2009 20:18:23 -0500
Subject: AP  -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <xDw5m.33863$S16.1632@newsfe23.iad>

"Musatov" <marty.musatov at gmail.com> wrote in message 
news:fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42 at x6g2000prc.googlegroups.com...

[snip-a-rooney]

> violator." Google could not be reached for comment.

Possibly because they were laughing so hard they couldn't hear their cell 
phones ringing ...? 




From scriber17 at aol.com  Thu Jul  9 21:29:58 2009
From: scriber17 at aol.com (The Masked Logician)
Date: Thu, 9 Jul 2009 18:29:58 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<xDw5m.33863$S16.1632@newsfe23.iad>
Message-ID: <7657db2e-71b3-4a49-b70f-127e362824a2@x5g2000prf.googlegroups.com>

On Jul 9, 6:18?pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> "Musatov" <marty.musa... at gmail.com> wrote in message
>
> news:fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42 at x6g2000prc.googlegroups.com...
>
> [snip-a-rooney]
>
> > violator." Google could not be reached for comment.
>
> Possibly because they were laughing so hard they couldn't hear their cell
> phones ringing ...?

Thank you for your comment Bruce C. Baker. Are you aware you're dead?

http://wcc.dli.mt.gov/B/BAKER_BRUCE_SJ_DECISION.htm

http://MeAmI.org

"The Best Search Engine for Fat Dead Guys named Bruce"


From matt.dubins at sympatico.ca  Thu Jul  9 21:36:05 2009
From: matt.dubins at sympatico.ca (inkhorn)
Date: Thu, 9 Jul 2009 18:36:05 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big string?
Message-ID: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>

Hi all,

For one of my projects, I came across the need to check if one of many
items from a list of strings could be found in a long string.  I came
up with a pretty quick helper function to check this, but I just want
to find out if there's something a little more elegant than what I've
cooked up.  The helper function follows:

def list_items_in_string(list_items, string):
    for item in list_items:
        if item in string:
            return True
    return False

So if you define a list x = ['Blah','Yadda','Hoohoo'] and a string y =
'Yip yip yippee Blah' and you run list_items_in_string(x, y), it
should return True.

Any ideas how to make that function look nicer? :)

Matt Dubins


From david250 at videotron.ca  Thu Jul  9 21:41:53 2009
From: david250 at videotron.ca (David Bernier)
Date: Thu, 09 Jul 2009 21:41:53 -0400
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <h3669102pl7@news7.newsguy.com>

Musatov wrote:
> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan.  The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
[ snip ]

I wonder what _AP_ means ...

David Bernier


From clp2 at rebertia.com  Thu Jul  9 21:43:31 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 18:43:31 -0700
Subject: How to check if any item from a list of strings is in a big 
	string?
In-Reply-To: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <50697b2c0907091843m174a065dx86e5ca6c21776a63@mail.gmail.com>

On Thu, Jul 9, 2009 at 6:36 PM, inkhorn<matt.dubins at sympatico.ca> wrote:
> Hi all,
>
> For one of my projects, I came across the need to check if one of many
> items from a list of strings could be found in a long string. ?I came
> up with a pretty quick helper function to check this, but I just want
> to find out if there's something a little more elegant than what I've
> cooked up. ?The helper function follows:
>
> def list_items_in_string(list_items, string):
> ? ?for item in list_items:
> ? ? ? ?if item in string:
> ? ? ? ? ? ?return True
> ? ?return False
>
> So if you define a list x = ['Blah','Yadda','Hoohoo'] and a string y =
> 'Yip yip yippee Blah' and you run list_items_in_string(x, y), it
> should return True.
>
> Any ideas how to make that function look nicer? :)

any(substr in y for substr in x)

Note that any() was added in Python 2.5

Cheers,
Chris
-- 
http://blog.rebertia.com


From fridrik at pyth.net  Thu Jul  9 21:45:01 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Fri, 10 Jul 2009 01:45:01 +0000
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <8BCC0DC4-7ADB-496C-AE87-5C419656CD73@pyth.net>

I'll be the first to admit it.  The point of writing a fake story by  
Associated Press and publishing it on a programming mailing list is  
totally beyond me.

Confoundedly yours,
Fri?rik M?r

From scriber17 at aol.com  Thu Jul  9 21:48:17 2009
From: scriber17 at aol.com (The Masked Logician)
Date: Thu, 9 Jul 2009 18:48:17 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h3669102pl7@news7.newsguy.com>
Message-ID: <90319430-9fdf-4286-b19a-8b1a852f75a9@g7g2000prg.googlegroups.com>

On Jul 9, 6:41?pm, David Bernier <david... at videotron.ca> wrote:
> Musatov wrote:
> > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > its adopted use in Pakistan. ?The search engine has grown in
> > popularity 10,000 fold following its Beta test launch three months ago
> > in April, 2009. Supporters of the site claim it is better than rival
> > Google upon which platform it is based. Controversy arose after
> > MeAmI.org search code allowed users to search other users Google
> > results with no advertising. "It is truly an innovative thing we are
> > doing," said Founder and CEO, Martin Musatov. "Letting users search
>
> [ snip ]
>
> I wonder what _AP_ means ...
>
> David Bernier

1. Dec 16, 2008 ... "Staffers recognize the tough times, but they also
understand that quality journalism at AP means attracting and
retaining the best ...
www.google.com/.../afp/.../ALeqM5gSCzjMBFqxtXCVC-am3ve59koBYQ

2. Business Accounting and Bookkeeping question: What does AP mean?
many things inc. associated press.
wiki.answers.com/Q/What_does_AP_mean

Found: http://www.meami.org/?cx=000961116824240632825%3A5n3yth9xwbo&cof=FORID%3A9%3B+NB%3A1&ie=UTF-8&q=AP+means#943

3. David Bernier - Wikipedia, the free encyclopedia David Enrique
Bernier also known as "Kike" (born January 21, 1977) former Secretary
of Sports and Recreation of Puerto Rico as well as Executive Director
of ...
en.wikipedia.org/wiki/David_Bernier

Found: http://www.meami.org/?cx=000961116824240632825%3A5n3yth9xwbo&cof=FORID%3A9%3B+NB%3A1&ie=UTF-8&q=David+Bernier#913

http://MeAmI.org

"Use it to fend off assholes."


From aahz at pythoncraft.com  Thu Jul  9 22:00:21 2009
From: aahz at pythoncraft.com (Aahz)
Date: 9 Jul 2009 19:00:21 -0700
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2up7a$epu$1@ger.gmane.org> <h30dfc$ke2$1@ger.gmane.org>
	<mailman.2905.1247159861.8015.python-list@python.org>
Message-ID: <h367bl$2ot$1@panix3.panix.com>

In article <mailman.2905.1247159861.8015.python-list at python.org>,
Joshua Kugler  <joshua at joshuakugler.com> wrote:
>Joshua Kugler wrote:
>>
>> Sorry about that...since pysqlite and APSW are both discusses on the
>> pysqlite list, I had made an incorrect assumption. Oops.
>
>"are both discusses?"  Yeef, I must have been out of it.  Discussed, thank
>you. :)

Who's Yeef?  ;-)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From jason at powerpull.net  Thu Jul  9 22:06:35 2009
From: jason at powerpull.net (Jason S. Friedman)
Date: Fri, 10 Jul 2009 02:06:35 +0000
Subject: language analysis to enforce code standards
In-Reply-To: <mailman.9989.1246930194.8014.python-list@python.org>
References: <mailman.9989.1246930194.8014.python-list@python.org>
Message-ID: <4A56A22B.5050204@powerpull.net>

Hello, I administer the Informatica ETL tool at my company.  Part of 
that role involves creating and enforcing standards.  I want the 
Informatica developers to add comments to certain key objects and I want 
to be able to verify (in an automated fashion) that they have done so.

I cannot merely check for non-emptiness; that is trivial to circumvent. 
  On the other hand, I probably do not need to be able to catch 
developers who are determined to not create comments.  There are not too 
many of them and perhaps they will find it is easier to write a (useful) 
comment than to game the system.

Any thoughts on how I might proceed?  Stated plainly, how can I tell 
when a string more-or-less forms at least one phrase?


From marty.musatov at gmail.com  Thu Jul  9 22:14:08 2009
From: marty.musatov at gmail.com (Martin Musatov)
Date: Thu, 9 Jul 2009 19:14:08 -0700
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <8BCC0DC4-7ADB-496C-AE87-5C419656CD73@pyth.net>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<8BCC0DC4-7ADB-496C-AE87-5C419656CD73@pyth.net>
Message-ID: <cf9a0a8b0907091914n470e44e5y3c392e8fff71fe4c@mail.gmail.com>

Thank you.
Martin Musatov

2009/7/9 Fri?rik M?r J?nsson <fridrik at pyth.net>

> I'll be the first to admit it.  The point of writing a fake story by
> Associated Press and publishing it on a programming mailing list is totally
> beyond me.
>
> Confoundedly yours,
> Fri?rik M?r
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/39a5926c/attachment.html>

From rogerb at rogerbinns.com  Thu Jul  9 22:15:00 2009
From: rogerb at rogerbinns.com (Roger Binns)
Date: Thu, 09 Jul 2009 19:15:00 -0700
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <h34dsu$a4j$1@lec.cs.unibo.it>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
Message-ID: <h36875$2bs$1@ger.gmane.org>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

jacopo mondi wrote:
> Hi all, I need to patch socketmodule.c (the _socket module) in order to
> add support to an experimental socket family.

You may find it considerably easier to use ctypes since that will avoid
the need for any patching.  You'll also be able to control how read and
write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
os.fdopen to convert your raw file descriptor into a Python file object
if appropriate.

If you do use ctypes then you'll only need to distribute pure Python
source code.

Roger
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkpWpCAACgkQmOOfHg372QQq0QCbB+rslUqK/AuUu0gA6N4m01Jo
C8IAn3EkzFKCyt/K5WiuCnw3jzORBQh5
=JCv+
-----END PGP SIGNATURE-----



From nobody at nowhere.com  Thu Jul  9 22:28:04 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 10 Jul 2009 03:28:04 +0100
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
Message-ID: <pan.2009.07.10.02.28.04.344000@nowhere.com>

On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:

> Nobody says you shouldn't check your data. Only that "assert" is not the  
> right way to do that.

"assert" is not the right way to check your *inputs*. It's a perfectly
reasonable way to check data which "should" be valid, as well as a way to
document what variables are supposed to contain.



From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 22:42:04 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 02:42:04 GMT
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
Message-ID: <pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>

On Fri, 10 Jul 2009 02:06:35 +0000, Jason S. Friedman wrote:

> Hello, I administer the Informatica ETL tool at my company.  Part of
> that role involves creating and enforcing standards.  I want the
> Informatica developers to add comments to certain key objects and I want
> to be able to verify (in an automated fashion) that they have done so.
> 
> I cannot merely check for non-emptiness; that is trivial to circumvent.
>   On the other hand, I probably do not need to be able to catch
> developers who are determined to not create comments.  There are not too
> many of them and perhaps they will find it is easier to write a (useful)
> comment than to game the system.
> 
> Any thoughts on how I might proceed?  Stated plainly, how can I tell
> when a string more-or-less forms at least one phrase?

Define "phrase".


if len(s) > 0:
    print "at least one character"
if len(s.split()) > 0:
    print "at least one word"
if len(s.split('\n') > 0:
    print "at least one line"



-- 
Steven


From timr at probo.com  Thu Jul  9 22:52:58 2009
From: timr at probo.com (Tim Roberts)
Date: Thu, 09 Jul 2009 19:52:58 -0700
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
	<cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>
Message-ID: <k1bd555692idl987pauglkg87mmgsihj1q@4ax.com>

Fred Atkinson <fatkinson at mishmash.com> wrote:
>
>I wonder why they don't just have a function to return it instead of
>putting you through all of that?  

In CGI, EVERYTHING gets communicated through environment variables.  That
(and the stdin stream) is really the only option, since you get a new
process for every request.

The Python CGI module doesn't provide a wrapper function because this
information is just not useful.  Most corporate users sit behind proxies,
so everyone at the company appears to come from the same IP.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From nobody at nowhere.com  Thu Jul  9 22:53:57 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 10 Jul 2009 03:53:57 +0100
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <pan.2009.07.10.02.53.57.172000@nowhere.com>

On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:

> For one of my projects, I came across the need to check if one of many
> items from a list of strings could be found in a long string.

If you need to match many strings or very long strings against the same
list of items, the following should (theoretically) be optimal:

	r = re.compile('|'.join(map(re.escape,list_items)))
	...
	result = r.search(string)



From david250 at videotron.ca  Thu Jul  9 22:54:16 2009
From: david250 at videotron.ca (David Bernier)
Date: Thu, 09 Jul 2009 22:54:16 -0400
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <h36agp02ste@news7.newsguy.com>

Musatov wrote:
> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan.  The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
> the results of other Google users immediately results in a level of
> accuracy and relevance above and beyond Google." Google changed their
> API following the launch or MeAmI.org and explored the possibility of
> blocking site access from MeAmI.org to Google search results but was
> unable to do so. Critics of MeAmI.org say what it is doing is
> tantamount to intellectual theft. When asked about this topper Musatov
> exclaimed, "The Internet was made for people, not companies." An
> analyst at Goldman Sachs says, requesting to remain anonymous,
> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> global activism and to tell you the truth, this makes it much more
> likely an acquisition target than potential intellectual property
> violator." Google could not be reached for comment.

Mr. Musatov,  do you know who originally wrote the
article above?

Thank you.

David Bernier


From zac256 at gmail.com  Thu Jul  9 22:54:47 2009
From: zac256 at gmail.com (Zac Burns)
Date: Thu, 9 Jul 2009 19:54:47 -0700
Subject: psyco V2 beta2 benchmark
In-Reply-To: <h2nhhs$g5m$00$1@news.t-online.com>
References: <h2nhhs$g5m$00$1@news.t-online.com>
Message-ID: <333edbe80907091954u7451e11fhf9600d1e2549137c@mail.gmail.com>

Where do you get this beta? I heard that Psyco V2 is coming out but
can't find anything on their site to support this.

--
Zachary Burns
(407)590-4814
Aim - Zac256FL
Production Engineer (Digital Overlord)
Zindagi Games



On Sat, Jul 4, 2009 at 5:26 AM, larudwer<larudwer at freenet.de> wrote:
> just out of curiosity i've downloaded the latest Version of Psyco V2 Beta 2
> and run the benchmarks against the old Version of psyco 1.6
>
> Because it might be of common interest, i am posting the results here.
>
> My machine is a Pentium D 3.2 Ghz running Windows XP SP 3 and Python 2.6.2.
> Psyco V2 was built with 4.3.3-tdm-1 mingw32 with optimisation flags changed
> to -O3
>
>
> Benchmark ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? | avg. Base time | psyco 1.6 time
> | psyco 2.0 time | ratio ? ? | possible error +-
> time_anyall all_bool_genexp ? ? ? ? ? ? ? | 2.270 ? ? ? ? ?| 2.250
> | 2.420 ? ? ? ? ?| 0.930 ? ? | 8.3 %
> time_anyall all_bool_listcomp ? ? ? ? ? ? | 3.450 ? ? ? ? ?| 1.900
> | 1.910 ? ? ? ? ?| 0.995 ? ? | 0.0 %
> time_anyall all_genexp ? ? ? ? ? ? ? ? ? ?| 1.970 ? ? ? ? ?| 1.940
> | 2.160 ? ? ? ? ?| 0.898 ? ? | 9.6 %
> time_anyall all_listcomp ? ? ? ? ? ? ? ? ?| 3.485 ? ? ? ? ?| 1.660
> | 1.660 ? ? ? ? ?| 1.000 ? ? | 1.4 %
> time_anyall all_loop ? ? ? ? ? ? ? ? ? ? ?| 0.665 ? ? ? ? ?| 0.090
> | 0.090 ? ? ? ? ?| 1.000 ? ? | 4.4 %
> time_anyall any_bool_genexp ? ? ? ? ? ? ? | 2.215 ? ? ? ? ?| 2.130
> | 2.340 ? ? ? ? ?| 0.910 ? ? | 10.0 %
> time_anyall any_bool_listcomp ? ? ? ? ? ? | 3.620 ? ? ? ? ?| 1.930
> | 1.940 ? ? ? ? ?| 0.995 ? ? | 9.0 %
> time_anyall any_genexp ? ? ? ? ? ? ? ? ? ?| 1.985 ? ? ? ? ?| 1.920
> | 2.180 ? ? ? ? ?| 0.881 ? ? | 10.1 %
> time_anyall any_listcomp ? ? ? ? ? ? ? ? ?| 3.360 ? ? ? ? ?| 1.680
> | 1.680 ? ? ? ? ?| 1.000 ? ? | 8.0 %
> time_anyall any_loop ? ? ? ? ? ? ? ? ? ? ?| 0.660 ? ? ? ? ?| 0.090
> | 0.090 ? ? ? ? ?| 1.000 ? ? | 3.0 %
> time_builtins chr(i) ? ? ? ? ? ? ? ? ? ? ?| 2.420 ? ? ? ? ?| 0.010
> | 0.010 ? ? ? ? ?| 1.000 ? ? | 0.0 %
> time_builtins hash(i) ? ? ? ? ? ? ? ? ? ? | 1.280 ? ? ? ? ?| 0.370
> | 0.080 ? ? ? ? ?| 4.625 ? ? | 8.1 %
> time_builtins int(round(f)) ? ? ? ? ? ? ? | 2.635 ? ? ? ? ?| 1.510
> | 1.120 ? ? ? ? ?| 1.348 ? ? | 0.4 %
> time_builtins min ? ? ? ? ? ? ? ? ? ? ? ? | 0.535 ? ? ? ? ?| 0.520
> | 0.120 ? ? ? ? ?| 4.333 ? ? | 1.9 %
> time_builtins min_kw ? ? ? ? ? ? ? ? ? ? ?| 4.430 ? ? ? ? ?| 4.400
> | 0.160 ? ? ? ? ?| 27.500 ? ?| 0.5 %
> time_builtins ord(i) ? ? ? ? ? ? ? ? ? ? ?| 0.320 ? ? ? ? ?| 0.000
> | 0.000 ? ? ? ? ?| 1.000 ? ? | 6.5 %
> time_builtins pow ? ? ? ? ? ? ? ? ? ? ? ? | 0.345 ? ? ? ? ?| 0.230
> | 0.150 ? ? ? ? ?| 1.533 ? ? | 2.9 %
> time_builtins reduce ? ? ? ? ? ? ? ? ? ? ?| 0.735 ? ? ? ? ?| 0.710
> | 0.020 ? ? ? ? ?| 35.498 ? ?| 1.4 %
> time_builtins round(f) ? ? ? ? ? ? ? ? ? ?| 1.720 ? ? ? ? ?| 0.890
> | 0.400 ? ? ? ? ?| 2.225 ? ? | 1.2 %
> time_builtins sums ? ? ? ? ? ? ? ? ? ? ? ?| 0.180 ? ? ? ? ?| 0.180
> | 0.100 ? ? ? ? ?| 1.800 ? ? | 0.0 %
> time_fib matrix ? ? ? ? ? ? ? ? ? ? ? ? ? | 0.425 ? ? ? ? ?| 0.360
> | 0.360 ? ? ? ? ?| 1.000 ? ? | 2.3 %
> time_fib recursive ? ? ? ? ? ? ? ? ? ? ? ?| 0.000 ? ? ? ? ?| 0.000
> | 0.000 ? ? ? ? ?| 1.000 ? ? | 0.0 %
> time_fib takahashi ? ? ? ? ? ? ? ? ? ? ? ?| 0.410 ? ? ? ? ?| 0.320
> | 0.330 ? ? ? ? ?| 0.970 ? ? | 0.0 %
> time_generators call next just many times | 0.900 ? ? ? ? ?| 0.630
> | 0.970 ? ? ? ? ?| 0.649 ? ? | 4.3 %
> time_generators iterate just many times ? | 0.660 ? ? ? ? ?| 0.550
> | 0.950 ? ? ? ? ?| 0.579 ? ? | 3.1 %
> time_generators send and loop 1000 ? ? ? ?| 2.805 ? ? ? ? ?| 2.540
> | 0.060 ? ? ? ? ?| 42.333 ? ?| 9.8 %
> time_generators send call loop 1000 ? ? ? | 2.505 ? ? ? ? ?| 2.940
> | 0.060 ? ? ? ? ?| 48.999 ? ?| 10.9 %
> time_generators send just many times ? ? ?| 1.280 ? ? ? ? ?| 0.590
> | 0.980 ? ? ? ? ?| 0.602 ? ? | 3.1 %
> time_iter iter ? ? ? ? ? ? ? ? ? ? ? ? ? ?| 1.490 ? ? ? ? ?| 0.590
> | 0.440 ? ? ? ? ?| 1.341 ? ? | 5.5 %
> time_math floats ? ? ? ? ? ? ? ? ? ? ? ? ?| 2.910 ? ? ? ? ?| 1.500
> | 1.630 ? ? ? ? ?| 0.920 ? ? | 0.7 %
> time_properties method_get ? ? ? ? ? ? ? ?| 0.935 ? ? ? ? ?| 0.120
> | 0.130 ? ? ? ? ?| 0.923 ? ? | 1.1 %
> time_properties method_set ? ? ? ? ? ? ? ?| 1.005 ? ? ? ? ?| 0.170
> | 0.180 ? ? ? ? ?| 0.944 ? ? | 1.0 %
> time_properties property_get ? ? ? ? ? ? ?| 0.960 ? ? ? ? ?| 0.740
> | 0.100 ? ? ? ? ?| 7.400 ? ? | 2.1 %
> time_properties property_set ? ? ? ? ? ? ?| 1.020 ? ? ? ? ?| 0.920
> | 0.930 ? ? ? ? ?| 0.989 ? ? | 0.0 %
> time_properties pyproperty_get ? ? ? ? ? ?| 1.535 ? ? ? ? ?| 1.310
> | 0.140 ? ? ? ? ?| 9.357 ? ? | 0.7 %
> time_properties pyproperty_set ? ? ? ? ? ?| 1.030 ? ? ? ? ?| 0.920
> | 0.930 ? ? ? ? ?| 0.989 ? ? | 2.0 %
> time_subdist subdist(i) ? ? ? ? ? ? ? ? ? | 3.665 ? ? ? ? ?| 1.640
> | 6.140 ? ? ? ? ?| 0.267 ? ? | 0.8 %
> time_sums rounding ? ? ? ? ? ? ? ? ? ? ? ?| 0.800 ? ? ? ? ?| 0.790
> | 0.810 ? ? ? ? ?| 0.975 ? ? | 2.5 %
>
>
> Running new timings with
> C:\Programme\GNU\python26\lib\site-packages\psyco\_psyco.pyd Sat Jul 04
> 12:09:07 2009
>
> time_anyall ? ?: all_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.36 ? ? psyco:
> 2.42 ? ? ratio: ?0.97
> time_anyall ? ?: all_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.45 ? ? psyco:
> 1.91 ? ? ratio: ?1.80
> time_anyall ? ?: all_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 2.06 ? ? psyco:
> 2.16 ? ? ratio: ?0.95
> time_anyall ? ?: all_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.51 ? ? psyco:
> 1.66 ? ? ratio: ?2.11
> time_anyall ? ?: all_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.65 ? ? psyco:
> 0.09 ? ? ratio: ?7.03
> time_anyall ? ?: any_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.32 ? ? psyco:
> 2.34 ? ? ratio: ?0.99
> time_anyall ? ?: any_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.45 ? ? psyco:
> 1.94 ? ? ratio: ?1.78
> time_anyall ? ?: any_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 2.08 ? ? psyco:
> 2.18 ? ? ratio: ?0.96
> time_anyall ? ?: any_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.49 ? ? psyco:
> 1.68 ? ? ratio: ?2.08
> time_anyall ? ?: any_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.65 ? ? psyco:
> 0.09 ? ? ratio: ?7.05
> time_builtins ?: chr(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.42 ? ? psyco:
> 0.01 ? ? ratio: 197.40
> time_builtins ?: hash(i) ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 1.33 ? ? psyco:
> 0.08 ? ? ratio: 17.69
> time_builtins ?: int(round(f)) ? ? ? ? ? ? ? ? ?plain: ? 2.63 ? ? psyco:
> 1.12 ? ? ratio: ?2.36
> time_builtins ?: min ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.53 ? ? psyco:
> 0.12 ? ? ratio: ?4.28
> time_builtins ?: min_kw ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 4.44 ? ? psyco:
> 0.16 ? ? ratio: 28.58
> time_builtins ?: ord(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.33 ? ? psyco:
> 0.00 ? ? ratio: 123.57
> time_builtins ?: pow ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.34 ? ? psyco:
> 0.15 ? ? ratio: ?2.24
> time_builtins ?: reduce ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.74 ? ? psyco:
> 0.02 ? ? ratio: 40.93
> time_builtins ?: round(f) ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.73 ? ? psyco:
> 0.40 ? ? ratio: ?4.38
> time_builtins ?: sums ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.18 ? ? psyco:
> 0.10 ? ? ratio: ?1.80
> time_fib ? ? ? : matrix ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.42 ? ? psyco:
> 0.36 ? ? ratio: ?1.18
> time_fib ? ? ? : recursive ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.00 ? ? psyco:
> 0.00 ? ? ratio: 19.45
> time_fib ? ? ? : takahashi ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.41 ? ? psyco:
> 0.33 ? ? ratio: ?1.25
> time_generators: send call loop 1000 ? ? ? ? ? ?plain: ? 2.36 ? ? psyco:
> 0.06 ? ? ratio: 41.30
> time_generators: send and loop 1000 ? ? ? ? ? ? plain: ? 2.66 ? ? psyco:
> 0.06 ? ? ratio: 46.69
> time_generators: send just many times ? ? ? ? ? plain: ? 1.26 ? ? psyco:
> 0.98 ? ? ratio: ?1.29
> time_generators: iterate just many times ? ? ? ?plain: ? 0.67 ? ? psyco:
> 0.95 ? ? ratio: ?0.70
> time_generators: call next just many times ? ? ?plain: ? 0.88 ? ? psyco:
> 0.97 ? ? ratio: ?0.91
> time_iter ? ? ?: iter ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.53 ? ? psyco:
> 0.44 ? ? ratio: ?3.47
> time_math ? ? ?: floats ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.90 ? ? psyco:
> 1.63 ? ? ratio: ?1.78
> time_properties: method_get ? ? ? ? ? ? ? ? ? ? plain: ? 0.93 ? ? psyco:
> 0.13 ? ? ratio: ?7.22
> time_properties: method_set ? ? ? ? ? ? ? ? ? ? plain: ? 1.00 ? ? psyco:
> 0.18 ? ? ratio: ?5.61
> time_properties: property_get ? ? ? ? ? ? ? ? ? plain: ? 0.95 ? ? psyco:
> 0.10 ? ? ratio: ?9.26
> time_properties: property_set ? ? ? ? ? ? ? ? ? plain: ? 1.02 ? ? psyco:
> 0.93 ? ? ratio: ?1.09
> time_properties: pyproperty_get ? ? ? ? ? ? ? ? plain: ? 1.54 ? ? psyco:
> 0.14 ? ? ratio: 10.80
> time_properties: pyproperty_set ? ? ? ? ? ? ? ? plain: ? 1.04 ? ? psyco:
> 0.93 ? ? ratio: ?1.12
> time_subdist ? : subdist(i) ? ? ? ? ? ? ? ? ? ? plain: ? 3.68 ? ? psyco:
> 6.14 ? ? ratio: ?0.60
> time_sums ? ? ?: rounding ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.79 ? ? psyco:
> 0.81 ? ? ratio: ?0.98
>
>
> Running new timings with original psyco
>
> time_anyall ? ?: all_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.18 ? ? psyco:
> 2.25 ? ? ratio: ?0.97
> time_anyall ? ?: all_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.45 ? ? psyco:
> 1.90 ? ? ratio: ?1.82
> time_anyall ? ?: all_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 1.88 ? ? psyco:
> 1.94 ? ? ratio: ?0.97
> time_anyall ? ?: all_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.46 ? ? psyco:
> 1.66 ? ? ratio: ?2.09
> time_anyall ? ?: all_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.68 ? ? psyco:
> 0.09 ? ? ratio: ?7.34
> time_anyall ? ?: any_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.11 ? ? psyco:
> 2.13 ? ? ratio: ?0.99
> time_anyall ? ?: any_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.79 ? ? psyco:
> 1.93 ? ? ratio: ?1.96
> time_anyall ? ?: any_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 1.89 ? ? psyco:
> 1.92 ? ? ratio: ?0.98
> time_anyall ? ?: any_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.23 ? ? psyco:
> 1.68 ? ? ratio: ?1.92
> time_anyall ? ?: any_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.67 ? ? psyco:
> 0.09 ? ? ratio: ?7.26
> time_builtins ?: chr(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.42 ? ? psyco:
> 0.01 ? ? ratio: 197.10
> time_builtins ?: hash(i) ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 1.23 ? ? psyco:
> 0.37 ? ? ratio: ?3.30
> time_builtins ?: int(round(f)) ? ? ? ? ? ? ? ? ?plain: ? 2.64 ? ? psyco:
> 1.51 ? ? ratio: ?1.75
> time_builtins ?: min ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.54 ? ? psyco:
> 0.52 ? ? ratio: ?1.03
> time_builtins ?: min_kw ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 4.42 ? ? psyco:
> 4.40 ? ? ratio: ?1.00
> time_builtins ?: ord(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.31 ? ? psyco:
> 0.00 ? ? ratio: 116.56
> time_builtins ?: pow ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.35 ? ? psyco:
> 0.23 ? ? ratio: ?1.50
> time_builtins ?: reduce ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.73 ? ? psyco:
> 0.71 ? ? ratio: ?1.03
> time_builtins ?: round(f) ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.71 ? ? psyco:
> 0.89 ? ? ratio: ?1.91
> time_builtins ?: sums ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.18 ? ? psyco:
> 0.18 ? ? ratio: ?1.03
> time_fib ? ? ? : matrix ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.43 ? ? psyco:
> 0.36 ? ? ratio: ?1.19
> time_fib ? ? ? : recursive ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.00 ? ? psyco:
> 0.00 ? ? ratio: 19.28
> time_fib ? ? ? : takahashi ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.41 ? ? psyco:
> 0.32 ? ? ratio: ?1.27
> time_generators: send call loop 1000 ? ? ? ? ? ?plain: ? 2.65 ? ? psyco:
> 2.94 ? ? ratio: ?0.90
> time_generators: send and loop 1000 ? ? ? ? ? ? plain: ? 2.95 ? ? psyco:
> 2.54 ? ? ratio: ?1.16
> time_generators: send just many times ? ? ? ? ? plain: ? 1.30 ? ? psyco:
> 0.59 ? ? ratio: ?2.23
> time_generators: iterate just many times ? ? ? ?plain: ? 0.65 ? ? psyco:
> 0.55 ? ? ratio: ?1.17
> time_generators: call next just many times ? ? ?plain: ? 0.92 ? ? psyco:
> 0.63 ? ? ratio: ?1.45
> time_iter ? ? ?: iter ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.45 ? ? psyco:
> 0.59 ? ? ratio: ?2.47
> time_math ? ? ?: floats ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.92 ? ? psyco:
> 1.50 ? ? ratio: ?1.95
> time_properties: method_get ? ? ? ? ? ? ? ? ? ? plain: ? 0.94 ? ? psyco:
> 0.12 ? ? ratio: ?7.88
> time_properties: method_set ? ? ? ? ? ? ? ? ? ? plain: ? 1.01 ? ? psyco:
> 0.17 ? ? ratio: ?6.08
> time_properties: property_get ? ? ? ? ? ? ? ? ? plain: ? 0.97 ? ? psyco:
> 0.74 ? ? ratio: ?1.31
> time_properties: property_set ? ? ? ? ? ? ? ? ? plain: ? 1.02 ? ? psyco:
> 0.92 ? ? ratio: ?1.12
> time_properties: pyproperty_get ? ? ? ? ? ? ? ? plain: ? 1.53 ? ? psyco:
> 1.31 ? ? ratio: ?1.17
> time_properties: pyproperty_set ? ? ? ? ? ? ? ? plain: ? 1.02 ? ? psyco:
> 0.92 ? ? ratio: ?1.11
> time_subdist ? : subdist(i) ? ? ? ? ? ? ? ? ? ? plain: ? 3.65 ? ? psyco:
> 1.64 ? ? ratio: ?2.23
> time_sums ? ? ?: rounding ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.81 ? ? psyco:
> 0.79 ? ? ratio: ?1.03
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 22:57:44 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 02:57:44 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
Message-ID: <pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>

On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:

> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
> 
>> Nobody says you shouldn't check your data. Only that "assert" is not
>> the right way to do that.
> 
> "assert" is not the right way to check your *inputs*. It's a perfectly
> reasonable way to check data which "should" be valid, as well as a way
> to document what variables are supposed to contain.

Where are those variables coming from?

The distinction really boils down to this:

* asserts should never fail. If there is any chance that an assertion 
might fail outside of test suites, then don't use assert.


You can't control what input the caller provides to a function, so unless 
the data is generated inside the function, a caller might provide 
something unexpected. Therefore, assert is inappropriate for checking 
function parameters, even if that function is "private" and only called 
by your own functions.

(1) So-called "private" or "internal" functions have a habit of becoming 
public, and then you have asserts in public functions.

(2) If public() calls _private(x), and _private uses assert to check the 
value of x, there is a risk that if public() is buggy and supplies an 
invalid x, the assertion will never be checked and _private() will return 
incorrect results.

(3) assert is absolutely unsuitable for enforcing pre-conditions and post-
conditions, unless such conditions are mere "guidelines", because assert 
can be switched off at runtime.



It's a fine line to draw. Obviously, if we think something *truly* can 
never fail, we don't bother checking it:

def add(x, y):
    result = x+y
    assert result-y == x
    assert result-x == y
    return result

is probably overkill for most programs, and yet surprisingly those 
assertions will commonly fail for float arguments!




-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 23:07:09 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 03:07:09 GMT
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>

On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:

> def list_items_in_string(list_items, string):
>     for item in list_items:
>         if item in string:
>             return True
>     return False
...
> Any ideas how to make that function look nicer? :)

Change the names. Reverse the order of the arguments. Add a docstring.

Otherwise looks pretty nice to me. Simple, straightforward, and correct.

If you're running Python 2.5 or better, then this is even shorter (and 
probably faster):

def contains(s, targets):
    """Return True if any item of targets is in string s."""
    return any(target in s for target in targets)



-- 
Steven


From tjreedy at udel.edu  Thu Jul  9 23:07:34 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 09 Jul 2009 23:07:34 -0400
Subject: tough-to-explain Python
In-Reply-To: <00720d76$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <h36b9m$7rs$1@ger.gmane.org>

Steven D'Aprano wrote:

> And speaking of binary search:
> 
> [quote]
> I was shocked to learn that the binary search program that Bentley PROVED 
> CORRECT and SUBSEQUENTLY TESTED [emphasis added] in Chapter 5 of 
> "Programming Pearls" contains a bug. Once I tell you what the it is, you 
> will understand why it escaped detection for two decades.
> [end quote]
> 
> http://northernplanets.blogspot.com/2006/07/nearly-all-binary-searches-are-broken.html
> 
> or http://tinyurl.com/nco6yv

The actual report is at
http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-it-nearly.html

The is the so called bug:
"In Programming Pearls Bentley says that the analogous line "sets m to 
the average of l and u, truncated down to the nearest integer." On the 
face of it, this assertion might appear correct, but it fails for large 
values of the int variables low and high. Specifically, it fails if the 
sum of low and high is greater than the maximum positive int value (231 
- 1). The sum overflows to a negative value, and the value stays 
negative when divided by two. In C this causes an array index out of 
bounds with unpredictable results. In Java, it throws 
ArrayIndexOutOfBoundsException."

The is *not* a bug is Bentley program. It is a bug in bad, buggy, insane 
integer arithmetic implementations. low + high should either return the 
right answer, as it will in Python, or raise an overflow error.

tjr



From sjmachin at lexicon.net  Thu Jul  9 23:07:58 2009
From: sjmachin at lexicon.net (John Machin)
Date: Thu, 9 Jul 2009 20:07:58 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<pan.2009.07.10.02.53.57.172000@nowhere.com>
Message-ID: <347b30b2-48a9-49cd-8e33-172325d34a34@v15g2000prn.googlegroups.com>

On Jul 10, 12:53?pm, Nobody <nob... at nowhere.com> wrote:
> On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:
> > For one of my projects, I came across the need to check if one of many
> > items from a list of strings could be found in a long string.
>
> If you need to match many strings or very long strings against the same
> list of items, the following should (theoretically) be optimal:
>
> ? ? ? ? r = re.compile('|'.join(map(re.escape,list_items)))
> ? ? ? ? ...
> ? ? ? ? result = r.search(string)

"theoretically optimal" happens only if the search mechanism builds a
DFA or similar out of the list of strings. AFAIK Python's re module
doesn't.

Try this:
http://hkn.eecs.berkeley.edu/~dyoo/python/ahocorasick/


From miki.tebeka at gmail.com  Thu Jul  9 23:14:30 2009
From: miki.tebeka at gmail.com (lazy1)
Date: Thu, 9 Jul 2009 20:14:30 -0700 (PDT)
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <128ab32f-3609-44a5-9fb3-1a7cb64f04e9@y10g2000prg.googlegroups.com>

Hello Daniel,

> Can someone recommend me a faster plotting library?
I found out gnuplot to be blazing fast for many many points.
I usually just call it using subprocess but there are Python bindings
to it somewhere as well.

HTH,
--
Miki <miki.tebeka at gmail.com>
http://pythonwise.blogspot.com




From http  Thu Jul  9 23:24:54 2009
From: http (Paul Rubin)
Date: 09 Jul 2009 20:24:54 -0700
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <7x63e1kynt.fsf@ruckus.brouhaha.com>

inkhorn <matt.dubins at sympatico.ca> writes:
> def list_items_in_string(list_items, string):
>     for item in list_items:
>         if item in string:
>             return True
>     return False

You could write that as (untested):

  def list_items_in_string(list_items, string):
     return any(item in string for item in list_items)

but there are faster algorithms you could use if the list is large and
you want to do the test on lots of long strings, etc.


From scriber77 at yahoo.com  Thu Jul  9 23:25:13 2009
From: scriber77 at yahoo.com (scriber77 at yahoo.com)
Date: Thu, 9 Jul 2009 20:25:13 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
Message-ID: <defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>

On Jul 9, 7:54?pm, David Bernier <david... at videotron.ca> wrote:
> Musatov wrote:
> > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > its adopted use in Pakistan. ?The search engine has grown in
> > popularity 10,000 fold following its Beta test launch three months ago
> > in April, 2009. Supporters of the site claim it is better than rival
> > Google upon which platform it is based. Controversy arose after
> > MeAmI.org search code allowed users to search other users Google
> > results with no advertising. "It is truly an innovative thing we are
> > doing," said Founder and CEO, Martin Musatov. "Letting users search
> > the results of other Google users immediately results in a level of
> > accuracy and relevance above and beyond Google." Google changed their
> > API following the launch or MeAmI.org and explored the possibility of
> > blocking site access from MeAmI.org to Google search results but was
> > unable to do so. Critics of MeAmI.org say what it is doing is
> > tantamount to intellectual theft. When asked about this topper Musatov
> > exclaimed, "The Internet was made for people, not companies." An
> > analyst at Goldman Sachs says, requesting to remain anonymous,
> > "MeAmI.org has a strong presence in promoting itself as a vehicle for
> > global activism and to tell you the truth, this makes it much more
> > likely an acquisition target than potential intellectual property
> > violator." Google could not be reached for comment.
>
> Mr. Musatov, ?do you know who originally wrote the
> article above?
>
> Thank you.
>
> David Bernier- Hide quoted text -
>
> - Show quoted text -

Hello, I am an anonymous Professor of Mathematics at a University in
the Midwest. You see, I have been contacted by this "Musatov" fellow
as well and posted a link he sent me to gather a second opinion. I was
immediately attacked by a Mr. Tim Chow from M.I.T. as though I was
him. I explained to him Mr. Musatov had contacted me, that I had read
his simple and very light 3 page paper and said I thought the work in
the equations was elegant and the mending of the binary with the
traditional mathematics symbols inventive. Listen, I understand this
"Musatov" character has annoyed a lot of you and apparently rightfully
so, at least to some extent, has gained a bit of contempt from the
community. But perhaps he is trying to see things a bit differently
and is just not getting the feedback he needs, so he is throwing
tantrums apparently across USENET.

Like I said before, I am just trying to do right by this person who
contacted me, and seemed to be a decent person with a genuine interest
in mathematics. He was very respectful.

Alas, I am at a loss on what specific feedback to give him on his
paper as though I am a professor of Mathematics, Computer Science is
not my specialty.

I told him I would try to get him some feedback on the equations on
page 3.  Would any of you be so kind to help me?

Here is the paper: http://MeAmI.org/pversusnp.pdf

I do thank you for your time.

Good day,

Professor X


From msjmb at tpg.com.au  Thu Jul  9 23:28:15 2009
From: msjmb at tpg.com.au (MichaelW)
Date: Thu, 9 Jul 2009 20:28:15 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
Message-ID: <109bd130-12d6-458b-879b-fa26afab678d@l5g2000pra.googlegroups.com>

On Jul 10, 1:25?pm, scribe... at yahoo.com wrote:
> On Jul 9, 7:54?pm, David Bernier <david... at videotron.ca> wrote:
>
>
>
>
>
> > Musatov wrote:
> > > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > > its adopted use in Pakistan. ?The search engine has grown in
> > > popularity 10,000 fold following its Beta test launch three months ago
> > > in April, 2009. Supporters of the site claim it is better than rival
> > > Google upon which platform it is based. Controversy arose after
> > > MeAmI.org search code allowed users to search other users Google
> > > results with no advertising. "It is truly an innovative thing we are
> > > doing," said Founder and CEO, Martin Musatov. "Letting users search
> > > the results of other Google users immediately results in a level of
> > > accuracy and relevance above and beyond Google." Google changed their
> > > API following the launch or MeAmI.org and explored the possibility of
> > > blocking site access from MeAmI.org to Google search results but was
> > > unable to do so. Critics of MeAmI.org say what it is doing is
> > > tantamount to intellectual theft. When asked about this topper Musatov
> > > exclaimed, "The Internet was made for people, not companies." An
> > > analyst at Goldman Sachs says, requesting to remain anonymous,
> > > "MeAmI.org has a strong presence in promoting itself as a vehicle for
> > > global activism and to tell you the truth, this makes it much more
> > > likely an acquisition target than potential intellectual property
> > > violator." Google could not be reached for comment.
>
> > Mr. Musatov, ?do you know who originally wrote the
> > article above?
>
> > Thank you.
>
> > David Bernier- Hide quoted text -
>
> > - Show quoted text -
>
> Hello, I am an anonymous Professor of Mathematics at a University in
> the Midwest. You see, I have been contacted by this "Musatov" fellow
> as well and posted a link he sent me to gather a second opinion. I was
> immediately attacked by a Mr. Tim Chow from M.I.T. as though I was
> him. I explained to him Mr. Musatov had contacted me, that I had read
> his simple and very light 3 page paper and said I thought the work in
> the equations was elegant and the mending of the binary with the
> traditional mathematics symbols inventive. Listen, I understand this
> "Musatov" character has annoyed a lot of you and apparently rightfully
> so, at least to some extent, has gained a bit of contempt from the
> community. But perhaps he is trying to see things a bit differently
> and is just not getting the feedback he needs, so he is throwing
> tantrums apparently across USENET.
>
> Like I said before, I am just trying to do right by this person who
> contacted me, and seemed to be a decent person with a genuine interest
> in mathematics. He was very respectful.
>
> Alas, I am at a loss on what specific feedback to give him on his
> paper as though I am a professor of Mathematics, Computer Science is
> not my specialty.
>
> I told him I would try to get him some feedback on the equations on
> page 3. ?Would any of you be so kind to help me?
>
> Here is the paper:http://MeAmI.org/pversusnp.pdf
>
> I do thank you for your time.
>
> Good day,
>
> Professor X- Hide quoted text -
>
> - Show quoted text -

Please see reply in the "Breathtaking..." thread. It will come as no
surprise to anyone that "Professor X" and "The Masked Logician" share
the same computer.

MichaelW.


From bcb at undisclosedlocation.net  Thu Jul  9 23:28:46 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Thu, 9 Jul 2009 22:28:46 -0500
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
Message-ID: <Kxy5m.119$Ly1.70@newsfe06.iad>


"Jason S. Friedman" <jason at powerpull.net> wrote in message 
news:mailman.2927.1247192026.8015.python-list at python.org...
> Hello, I administer the Informatica ETL tool at my company.  Part of that 
> role involves creating and enforcing standards.  I want the Informatica 
> developers to add comments to certain key objects and I want to be able to 
> verify (in an automated fashion) that they have done so.
>
> I cannot merely check for non-emptiness; that is trivial to circumvent. On 
> the other hand, I probably do not need to be able to catch developers who 
> are determined to not create comments.  There are not too many of them and 
> perhaps they will find it is easier to write a (useful) comment than to 
> game the system.
>
> Any thoughts on how I might proceed?  Stated plainly, how can I tell when 
> a string more-or-less forms at least one phrase?

Well, you *could* try analyzing the comment text using NLTK: 
http://www.nltk.org/





From bcb at undisclosedlocation.net  Thu Jul  9 23:33:25 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Thu, 9 Jul 2009 22:33:25 -0500
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
Message-ID: <5Cy5m.121$Ly1.67@newsfe06.iad>


<scriber77 at yahoo.com> wrote in message 
news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...

<ka-snip>

Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this! 




From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 23:41:43 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 03:41:43 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2931.1247195266.8015.python-list@python.org>
Message-ID: <pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>

On Thu, 09 Jul 2009 23:07:34 -0400, Terry Reedy wrote:

> Steven D'Aprano wrote:
> 
>> And speaking of binary search:
>> 
>> [quote]
>> I was shocked to learn that the binary search program that Bentley
>> PROVED CORRECT and SUBSEQUENTLY TESTED [emphasis added] in Chapter 5 of
>> "Programming Pearls" contains a bug. Once I tell you what the it is,
>> you will understand why it escaped detection for two decades. [end
>> quote]
>> 
>> http://northernplanets.blogspot.com/2006/07/nearly-all-binary-searches-
are-broken.html
>> 
>> or http://tinyurl.com/nco6yv
> 
> The actual report is at
> http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-
it-nearly.html
> 
> The is the so called bug:
> "In Programming Pearls Bentley says that the analogous line "sets m to
> the average of l and u, truncated down to the nearest integer." On the
> face of it, this assertion might appear correct, but it fails for large
> values of the int variables low and high. Specifically, it fails if the
> sum of low and high is greater than the maximum positive int value (231
> - 1). The sum overflows to a negative value, and the value stays
> negative when divided by two. In C this causes an array index out of
> bounds with unpredictable results. In Java, it throws
> ArrayIndexOutOfBoundsException."
> 
> The is *not* a bug is Bentley program.

Wow. That's an impressive set of typos :)


> It is a bug in bad, buggy, insane
> integer arithmetic implementations. low + high should either return the
> right answer, as it will in Python, or raise an overflow error.

Is binary search *supposed* to raise an overflow error if given more than 
2**30 elements? If not, then you're solving a different problem: it's 
just like binary search, but it only works up to a maximum number of 
elements. Now perhaps that's a legitimate problem to solve, but unless 
you make the change in behaviour clear up front, your code has failed to 
live up to specifications and therefore is buggy.

Is there something special about OverflowError that is "better" than 
ArrayIndexOutOfBoundsException?

I don't have "Programming Pearls", and unfortunately the section on 
binary search is not online:

http://netlib.bell-labs.com/cm/cs/pearls/sketch04.html

but there's no reason to imagine that the book will assume -- or even 
state as a requirement for binary search -- that addition will never 
overflow. Far from it: it seems to me that the author is very aware of 
real world constraints, and in the early 1980s, BigInt types were not 
something you took as a given.

Of course *binary search* as an algorithm is not broken. The bug was that 
"Programming Pearls" neglected to take into account overflow when you 
have more than 2**30 items. One way to take that into account is to 
insist on using a language like Python where addition can never overflow. 
But that's not the code presented in "Programming Pearls".


-- 
Steven


From marty.musatov at gmail.com  Thu Jul  9 23:43:08 2009
From: marty.musatov at gmail.com (Musatov)
Date: Thu, 9 Jul 2009 20:43:08 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
Message-ID: <c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>

On Jul 9, 7:54?pm, David Bernier <david... at videotron.ca> wrote:
> Musatov wrote:
> > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > its adopted use in Pakistan. ?The search engine has grown in
> > popularity 10,000 fold following its Beta test launch three months ago
> > in April, 2009. Supporters of the site claim it is better than rival
> > Google upon which platform it is based. Controversy arose after
> > MeAmI.org search code allowed users to search other users Google
> > results with no advertising. "It is truly an innovative thing we are
> > doing," said Founder and CEO, Martin Musatov. "Letting users search
> > the results of other Google users immediately results in a level of
> > accuracy and relevance above and beyond Google." Google changed their
> > API following the launch or MeAmI.org and explored the possibility of
> > blocking site access from MeAmI.org to Google search results but was
> > unable to do so. Critics of MeAmI.org say what it is doing is
> > tantamount to intellectual theft. When asked about this topper Musatov
> > exclaimed, "The Internet was made for people, not companies." An
> > analyst at Goldman Sachs says, requesting to remain anonymous,
> > "MeAmI.org has a strong presence in promoting itself as a vehicle for
> > global activism and to tell you the truth, this makes it much more
> > likely an acquisition target than potential intellectual property
> > violator." Google could not be reached for comment.
>
> Mr. Musatov, ?do you know who originally wrote the
> article above?
>
> Thank you.
>
> David Bernier- Hide quoted text -
>
> - Show quoted text -

Yes.


From timr at probo.com  Thu Jul  9 23:44:50 2009
From: timr at probo.com (Tim Roberts)
Date: Thu, 09 Jul 2009 20:44:50 -0700
Subject: How to use Python to interface with Web pages?
References: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
Message-ID: <r8ed55pkd47v35li0vdemrkse1jg1leena@4ax.com>

Peter <peter.milliken at gmail.com> wrote:
>
>Any help would be appreciated :-)
>
>I want to write an auction sniping tool in Python.

Please don't.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From timr at probo.com  Thu Jul  9 23:50:30 2009
From: timr at probo.com (Tim Roberts)
Date: Thu, 09 Jul 2009 20:50:30 -0700
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
Message-ID: <vded55tanedt94386elhh851j7felns1md@4ax.com>

TheSeeker <duane.kaufman at gmail.com> wrote:
>
>I am embarking on teaching myself Microsoft UI Automation using Python
>as the scripting language.

The University of North Carolina at Chapel Hill has a great Python package
called pyAA that does exactly this:

http://www.cs.unc.edu/Research/assist/developer.shtml
http://mindtrove.info/articles/gui-automation-with-pyaa/
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From scriptlearner at gmail.com  Fri Jul 10 01:29:15 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Thu, 9 Jul 2009 22:29:15 -0700 (PDT)
Subject: Looking for the right library for a simple HTTP client
Message-ID: <fccd9f2d-8021-4087-9a38-ace47fc40175@r15g2000pra.googlegroups.com>

I am trying to implement a simple client that can do the following:
1)to send the following kinds of HTTP requests and validate responses
1.1 GET
1.2 POST with application/x-www-form-urlencoded encoding
1.3 POST with multipart/form-data encoding

2)to set any number of (even duplicate) headers.  For example, I may
intentionally add the following Cookie: headers to a request:
Cookie: id_1=v1;Domain=sample.com;Path=/
Cookie: id_1=v1;Domain=sample.com;Path=/ <--same as the one above
Cookie: id_2=v1;Domain=sample.com;Path=/

3)to set proxy cfg so requests can go through a proxy server to reach
the target server.

4)to send multiple requests simultaneously.


I have Python 2.4.1 on Solaris 9 and 10, and I don't have any plan to
upgrade to latest version of Python.

I looked around and I found httplib and urllib.  Are they sufficient
for my tasks 1 to 3 above?  Any good sample codes will be great.
Thanks.


From david250 at videotron.ca  Fri Jul 10 01:45:36 2009
From: david250 at videotron.ca (David Bernier)
Date: Fri, 10 Jul 2009 01:45:36 -0400
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
Message-ID: <h36ki102d7m@news5.newsguy.com>

Musatov wrote:
> On Jul 9, 7:54 pm, David Bernier <david... at videotron.ca> wrote:
>> Musatov wrote:
>>> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
>>> its adopted use in Pakistan.  The search engine has grown in
>>> popularity 10,000 fold following its Beta test launch three months ago
>>> in April, 2009. Supporters of the site claim it is better than rival
>>> Google upon which platform it is based. Controversy arose after
>>> MeAmI.org search code allowed users to search other users Google
>>> results with no advertising. "It is truly an innovative thing we are
>>> doing," said Founder and CEO, Martin Musatov. "Letting users search
>>> the results of other Google users immediately results in a level of
>>> accuracy and relevance above and beyond Google." Google changed their
>>> API following the launch or MeAmI.org and explored the possibility of
>>> blocking site access from MeAmI.org to Google search results but was
>>> unable to do so. Critics of MeAmI.org say what it is doing is
>>> tantamount to intellectual theft. When asked about this topper Musatov
>>> exclaimed, "The Internet was made for people, not companies." An
>>> analyst at Goldman Sachs says, requesting to remain anonymous,
>>> "MeAmI.org has a strong presence in promoting itself as a vehicle for
>>> global activism and to tell you the truth, this makes it much more
>>> likely an acquisition target than potential intellectual property
>>> violator." Google could not be reached for comment.
>> Mr. Musatov,  do you know who originally wrote the
>> article above?
>>
>> Thank you.
>>
>> David Bernier- Hide quoted text -
>>
>> - Show quoted text -
> 
> Yes.

Mr. Musatov, do you know the name of the person who
originally wrote the article above?

Thank you.

David Bernier


From scriber77 at yahoo.com  Fri Jul 10 01:52:14 2009
From: scriber77 at yahoo.com (Floetry)
Date: Thu, 9 Jul 2009 22:52:14 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<5Cy5m.121$Ly1.67@newsfe06.iad>
Message-ID: <803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3@2g2000prl.googlegroups.com>

On Jul 9, 8:33?pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> <scribe... at yahoo.com> wrote in message
>
> news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...
>
> <ka-snip>
>
> Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this!

Any reason "ka"-snip?

Binomial Theorem: page 3. http://MeAmI.org/pversusnp.pdf



From s.deshe at gmail.com  Fri Jul 10 02:18:03 2009
From: s.deshe at gmail.com (slamdunk)
Date: Thu, 9 Jul 2009 23:18:03 -0700 (PDT)
Subject: way for a function to understand whether it's being run through a 
	OnCreate callback or not
Message-ID: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>

is there a way for a function to understand whether it's being run
through a OnCreate callback or not?
I have working functions that I want to recycle through the OnCreate
but need to catch the "nuke.thisNode()" bit inside them so they can
still function when called manually through other scripts functions.


From bcb at undisclosedlocation.net  Fri Jul 10 02:21:46 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Fri, 10 Jul 2009 01:21:46 -0500
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<5Cy5m.121$Ly1.67@newsfe06.iad>
	<803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3@2g2000prl.googlegroups.com>
Message-ID: <X3B5m.1452$yk5.1278@newsfe02.iad>


"Floetry" <scriber77 at yahoo.com> wrote in message 
news:803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3 at 2g2000prl.googlegroups.com...
On Jul 9, 8:33 pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> <scribe... at yahoo.com> wrote in message
>
> news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...
>
> <ka-snip>
>
> Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this!

Any reason "ka"-snip?

Binomial Theorem: page 3. http://MeAmI.org/pversusnp.pdf

_________________________________________________

Well, *Martin*, since you think I'm dead, it could only have been my "ka" 
that did the snipping. Surely a polymath of your vast accomplishments will 
have no problem with the religio-historical reference, eh, *Martin*? (I'm 
predicting that not only will you *not* recognize it, you'll find it beneath 
your notice. No fair googling, *Martin*!)






From clp2 at rebertia.com  Fri Jul 10 02:23:17 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 23:23:17 -0700
Subject: way for a function to understand whether it's being run through a
	OnCreate callback or not
In-Reply-To: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
References: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
Message-ID: <50697b2c0907092323n6da421f1o9b3faec654bd88e7@mail.gmail.com>

On Thu, Jul 9, 2009 at 11:18 PM, slamdunk<s.deshe at gmail.com> wrote:
> is there a way for a function to understand whether it's being run
> through a OnCreate callback or not?
> I have working functions that I want to recycle through the OnCreate
> but need to catch the "nuke.thisNode()" bit inside them so they can
> still function when called manually through other scripts functions.

Your question lacks context. What's an OnCreate callback?

Cheers,
Chris
-- 
http://blog.rebertia.com


From gherron at islandtraining.com  Fri Jul 10 02:59:22 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Thu, 09 Jul 2009 23:59:22 -0700
Subject: way for a function to understand whether it's being run through
	a 	OnCreate callback or not
In-Reply-To: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
References: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
Message-ID: <4A56E6CA.5090802@islandtraining.com>

slamdunk wrote:
> is there a way for a function to understand whether it's being run
> through a OnCreate callback or not?
> I have working functions that I want to recycle through the OnCreate
> but need to catch the "nuke.thisNode()" bit inside them so they can
> still function when called manually through other scripts functions.
>   
You've given us almost *NO* clue what you are talking about.   I suppose 
I could Google "onCreate", and perhaps "nuke" and "thisNode", and see 
what falls out.  But why would I?  If you want our help, *you* take the 
time to tell is what you are asking about. 

You may want to start here:  
http://www.catb.org/~esr/faqs/smart-questions.html#intro

Gary Herron



From kf9150 at gmail.com  Fri Jul 10 03:13:54 2009
From: kf9150 at gmail.com (Kelie)
Date: Fri, 10 Jul 2009 00:13:54 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<vded55tanedt94386elhh851j7felns1md@4ax.com>
Message-ID: <fc148aba-ee96-4306-9ee4-ef1d8efeb8d0@i6g2000yqj.googlegroups.com>

On Jul 9, 5:50?pm, Tim Roberts <t... at probo.com> wrote:
> The University of North Carolina at Chapel Hill has a great Python package
> called pyAA that does exactly this:
>
> http://www.cs.unc.edu/Research/assist/developer.shtmlhttp://mindtrove.info/articles/gui-automation-with-pyaa/
> --
> Tim Roberts, t... at probo.com

Thanks Tim. From this page http://sourceforge.net/projects/uncassist/files/,
there isn't a installer for Python2.5 or higher. Didn't find the
source code there either.



From marty.musatov at gmail.com  Fri Jul 10 03:19:40 2009
From: marty.musatov at gmail.com (Musatov)
Date: Fri, 10 Jul 2009 00:19:40 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<5Cy5m.121$Ly1.67@newsfe06.iad>
	<803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3@2g2000prl.googlegroups.com>
	<X3B5m.1452$yk5.1278@newsfe02.iad>
Message-ID: <1d58ce00-9436-4220-a7ad-fc586df6625c@h18g2000yqj.googlegroups.com>

On Jul 9, 11:21?pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> "Floetry" <scribe... at yahoo.com> wrote in message
>
> news:803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3 at 2g2000prl.googlegroups.com...
> On Jul 9, 8:33 pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
> wrote:
>
> > <scribe... at yahoo.com> wrote in message
>
> >news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...
>
> > <ka-snip>
>
> > Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this!
>
> Any reason "ka"-snip?
>
> Binomial Theorem: page 3.http://MeAmI.org/pversusnp.pdf
>
> _________________________________________________
>
> Well, *Martin*, since you think I'm dead, it could only have been my "ka"
> that did the snipping. Surely a polymath of your vast accomplishments will
> have no problem with the religio-historical reference, eh, *Martin*? (I'm
> predicting that not only will you *not* recognize it, you'll find it beneath
> your notice. No fair googling, *Martin*!)

I did not Google.

ka in ancient Egypt, the supposed spiritual part of an individual
human being or god, which survived (with the soul) after death and
could reside in a statue of the person.

ELIZABETH KNOWLES. "ka." The Oxford Dictionary of Phrase and Fable.
Oxford University Press. 2006. Encyclopedia.com. 10 Jul. 2009 <http://
www.encyclopedia.com>.

In a third class of religion?usually heavily interlaced with fetishism?
magic, momentary and special deities, nature gods, and deities
personifying natural functions (such as the Egyptian solar god Ra, the
Babylonian goddess of fertility Ishtar, the Greek sea-god Poseidon,
and the Hindu goddess of death and destruction *Ka*li) emerge and are
incorporated into a system of mythology and ritual. Sometimes they
take on distinctively human characteristics (see anthropomorphism).

The axis of reason - equinox, mass, and time - the orbits of ...Et a
basso profundo hashi-hashi-brek-a-time todo ka tiempo. > Vozacka
dozvola macarana lambada ... (&?&@?&?&?@&?&)) P. -- Musatov http://MeAmI.org
...


From martin at librador.com  Fri Jul 10 03:30:48 2009
From: martin at librador.com (Martin Vilcans)
Date: Fri, 10 Jul 2009 09:30:48 +0200
Subject: way for a function to understand whether it's being run through a
	OnCreate callback or not
In-Reply-To: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
References: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
Message-ID: <f782707a0907100030w7e86fd8dg5585c210f6cc50c@mail.gmail.com>

On Fri, Jul 10, 2009 at 8:18 AM, slamdunk<s.deshe at gmail.com> wrote:
> is there a way for a function to understand whether it's being run
> through a OnCreate callback or not?
> I have working functions that I want to recycle through the OnCreate
> but need to catch the "nuke.thisNode()" bit inside them so they can
> still function when called manually through other scripts functions.

I suppose you're programming for The Foundry's Nuke. Python is used in
lots of different contexts, and most people on this list use Python
for something totally unrelated to video.

As an attempt at answering your question, you can add a parameter to
your function that tells from where it's called. I.e. you put True in
the parameter when it is called from OnCreate, False when it is not.
But that isn't a very good design. A function should not need to care
from where it is called. You probably want to have the node as a
parameter to the function instead of calling nuke.thisNode inside of
it.

I can't find documentation for the OnCreate function online. Do you
mean that you can only call nuke.thisNode() from inside OnCreate?

Here's my guess of what I think you want to do:

def OnCreate():
    # call your function with the current node as argument
    your_function(nuke.thisNode())

def your_function(node):
    # The function takes a node as an argument.
    # Do whatever you want here

For more Nuke-specific questions, you'd probably get better results by
asking on the Nuke-python mailing list:

http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-python


-- 
martin at librador.com
http://www.librador.com


From dstanek at dstanek.com  Fri Jul 10 03:34:05 2009
From: dstanek at dstanek.com (David Stanek)
Date: Fri, 10 Jul 2009 03:34:05 -0400
Subject: Looking for the right library for a simple HTTP client
In-Reply-To: <fccd9f2d-8021-4087-9a38-ace47fc40175@r15g2000pra.googlegroups.com>
References: <fccd9f2d-8021-4087-9a38-ace47fc40175@r15g2000pra.googlegroups.com>
Message-ID: <de32cc030907100034j32a3f4c3y127bb3f94a41bb74@mail.gmail.com>

On Fri, Jul 10, 2009 at 1:29 AM,
scriptlearner at gmail.com<scriptlearner at gmail.com> wrote:
> I am trying to implement a simple client that can do the following:
> 1)to send the following kinds of HTTP requests and validate responses
> 1.1 GET
> 1.2 POST with application/x-www-form-urlencoded encoding
> 1.3 POST with multipart/form-data encoding
>
> 2)to set any number of (even duplicate) headers. ?For example, I may
> intentionally add the following Cookie: headers to a request:
> Cookie: id_1=v1;Domain=sample.com;Path=/
> Cookie: id_1=v1;Domain=sample.com;Path=/ <--same as the one above
> Cookie: id_2=v1;Domain=sample.com;Path=/
>
> 3)to set proxy cfg so requests can go through a proxy server to reach
> the target server.
>
> 4)to send multiple requests simultaneously.
>
>
> I have Python 2.4.1 on Solaris 9 and 10, and I don't have any plan to
> upgrade to latest version of Python.
>
> I looked around and I found httplib and urllib. ?Are they sufficient
> for my tasks 1 to 3 above? ?Any good sample codes will be great.
> Thanks.
> --
> http://mail.python.org/mailman/listinfo/python-list
>

I like urllib2. The examples[1] are pretty good.

[1] http://www.python.org/doc/2.4.1/lib/urllib2-examples.html

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From bhardwajjayesh at gmail.com  Fri Jul 10 03:54:52 2009
From: bhardwajjayesh at gmail.com (jayesh bhardwaj)
Date: Fri, 10 Jul 2009 00:54:52 -0700 (PDT)
Subject: Httplib issues
Message-ID: <017b8d15-6a4c-4a6c-8d92-1f8e8cbf4c6d@t33g2000yqe.googlegroups.com>

Hi,
i was trying to download file frm a terminal having apache with
httplib manipulation. It worked, now i want to upload file to the
terminal. Can this b done by httplib too?


From lie.1296 at gmail.com  Fri Jul 10 04:03:05 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 10 Jul 2009 08:03:05 GMT
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <mailman.2910.1247165872.8015.python-list@python.org>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>	<h34t9k$kp8$1@south.jnrs.ja.net>	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>	<op.uws939iha8ncjz@gnudebst>
	<mailman.2910.1247165872.8015.python-list@python.org>
Message-ID: <ZAC5m.3933$ze1.529@news-server.bigpond.net.au>

Fri?rik M?r J?nsson wrote:
> Hi Rhodri,
> 
>> It's only really a pitfall if you try to use the built-in after you've
>> redefined it.  That's the thing to keep an eye open for.
> 
> You're right, but in cases where you're editing a codebase which you
> didn't author entirely by yourself you may not be aware of that.
> 
> That said, if the codebase you're working on is structured (short,
> concise methods) you should be working with small, consumable scopes you
> can inhale in entirety before modifying.
> 
> Regards,
> Fri?rik M?r

But if you are responsible for a large codebase that you don't write
yourself, it is doubtful that you're a real newbie.


From lie.1296 at gmail.com  Fri Jul 10 04:47:51 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 10 Jul 2009 08:47:51 GMT
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <mailman.2924.1247184109.8015.python-list@python.org>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<mailman.2924.1247184109.8015.python-list@python.org>
Message-ID: <XeD5m.3944$ze1.1969@news-server.bigpond.net.au>

Simon Forman wrote:
> On Thu, Jul 9, 2009 at 9:42 AM, Nick<nleioatt at gmail.com> wrote:
> <snip>
>>    fields = line.split()
>>    for i in range(len(fields)):
>>        fields[i] = float(fields[i])
> 
> 
> instead of the above code you could say:
> 
> fields = [float(n) for n in in line.split()]
> 
> Have fun getting back into python! :]  (A lot has changed in the last few years)

>>> fields = [float(n) for n in in line.split()]
  File "<stdin>", line 1
    fields = [float(n) for n in in line.split()]
                                 ^
SyntaxError: invalid syntax

s/in in/in/


From jeremy+complangpython at jeremysanders.net  Fri Jul 10 04:51:29 2009
From: jeremy+complangpython at jeremysanders.net (Jeremy Sanders)
Date: Fri, 10 Jul 2009 09:51:29 +0100
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <h36veh$g4h$1@gemini.csx.cam.ac.uk>

tt-industries wrote:

> Hi,
> 
> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once. So far I have been using the ploting module
> of wxPython. However, it becomes unstable for more than 25000 points.
> Can someone recommend me a faster plotting library? It would be really
> cool if one could embed this in wxPython. If someone has an idea I
> would be very glad about answer.

Veusz can plot a line with that many points with that many points in a 
couple of seconds on my system. It's a bit faster without antialiasing, 
slower if you want to actually plot markers at each position.

Jeremy

-- 
Jeremy Sanders
http://www.jeremysanders.net/



From deets at nospam.web.de  Fri Jul 10 04:59:08 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 10 Jul 2009 10:59:08 +0200
Subject: Httplib issues
In-Reply-To: <017b8d15-6a4c-4a6c-8d92-1f8e8cbf4c6d@t33g2000yqe.googlegroups.com>
References: <017b8d15-6a4c-4a6c-8d92-1f8e8cbf4c6d@t33g2000yqe.googlegroups.com>
Message-ID: <7boe6sF249o1gU1@mid.uni-berlin.de>

jayesh bhardwaj schrieb:
> Hi,
> i was trying to download file frm a terminal having apache with
> httplib manipulation. It worked, now i want to upload file to the
> terminal. Can this b done by httplib too?

"Upload file to the terminal" makes no sense to me. You can upload 
something to a server. You can run a terminal. You can run a ssh-session 
to a server in a terminal. You can't upload to a terminal.

But you can use httplib (or better urllib2) to make http-post-requests 
to webservers.

And last but not least the ubiquious

http://catb.org/esr/faqs/smart-questions.html

Diez


From jeanmichel at sequans.com  Fri Jul 10 05:11:33 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 10 Jul 2009 11:11:33 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <pan.2009.07.10.02.28.04.344000@nowhere.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
Message-ID: <4A5705C5.6010301@sequans.com>

Nobody wrote:
> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>
>   
>> Nobody says you shouldn't check your data. Only that "assert" is not the  
>> right way to do that.
>>     
>
> "assert" is not the right way to check your *inputs*. It's a perfectly
> reasonable way to check data which "should" be valid, as well as a way to
> document what variables are supposed to contain.
>
>   
Maybe, one of the assert problem is a semantic issue. Assert is a 
convenient way to write in the code "This is a requirement, get lost if 
you don't fit in". However it seems we often forget that builtin asserts 
can be disabled.
One possible solution for those who prefer to write assertions instead a 
'if A then Exception' is to write their own assertion statement and 
**raise an exception** that will not be disabled at runtime.

Jea-Michel


From garabik-news-2005-05 at kassiopeia.juls.savba.sk  Fri Jul 10 05:23:54 2009
From: garabik-news-2005-05 at kassiopeia.juls.savba.sk (garabik-news-2005-05 at kassiopeia.juls.savba.sk)
Date: Fri, 10 Jul 2009 09:23:54 +0000 (UTC)
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com>
Message-ID: <h371ba$36l$1@aioe.org>

Tim Harig <usernet at ilthio.net> wrote:
> On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
>> I would like to learn a way of changing the colour of a particular
>> part of the output text. I've tried the following

> On Unix operating systems this would be done through the curses interface:
> 
> http://docs.python.org/library/curses.html

Or using ANSI colour codes:

colours = {
            'none'       :    "",
            'default'    :    "\033[0m",
            'bold'       :    "\033[1m",
            'underline'  :    "\033[4m",
            'blink'      :    "\033[5m",
            'reverse'    :    "\033[7m",
            'concealed'  :    "\033[8m",

            'black'      :    "\033[30m",
            'red'        :    "\033[31m",
            'green'      :    "\033[32m",
            'yellow'     :    "\033[33m",
            'blue'       :    "\033[34m",
            'magenta'    :    "\033[35m",
            'cyan'       :    "\033[36m",
            'white'      :    "\033[37m",

            'on_black'   :    "\033[40m",
            'on_red'     :    "\033[41m",
            'on_green'   :    "\033[42m",
            'on_yellow'  :    "\033[43m",
            'on_blue'    :    "\033[44m",
            'on_magenta' :    "\033[45m",
            'on_cyan'    :    "\033[46m",
            'on_white'   :    "\033[47m",

            'beep'       :    "\007",

            # non-standard attributes, supported by some terminals 
            'dark'         :    "\033[2m",
            'italic'       :    "\033[3m",
            'rapidblink'   :    "\033[6m",
            'strikethrough':    "\033[9m",
            }

print colours['red'], 'this is red', colours['blue'], 'blue', colours['on_green'], 'and with a green background', colours['default']

-- 
 -----------------------------------------------------------
| Radovan Garab?k http://kassiopeia.juls.savba.sk/~garabik/ |
| __..--^^^--..__    garabik @ kassiopeia.juls.savba.sk     |
 -----------------------------------------------------------
Antivirus alert: file .signature infected by signature virus.
Hi! I'm a signature virus! Copy me into your signature file to help me spread!


From roland at catalogix.se  Fri Jul 10 05:33:25 2009
From: roland at catalogix.se (Roland Hedberg)
Date: Fri, 10 Jul 2009 11:33:25 +0200
Subject: A zlib question
Message-ID: <80F42625-5FB2-438F-AFF2-913236A6D336@catalogix.se>

Hi!

I have a problem with zlib and compressing/decompressing according to  
RFC 1951.

It seems like I can decompress, something compressed according to RFC  
1951 by someone else, provided I set wbits to something negative (used  
-8 but I guess any negative number would work?).

But how can I compress using zlib so it doesn't add a gzip header ?

-- Roland 


From jeanmichel at sequans.com  Fri Jul 10 05:39:54 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 10 Jul 2009 11:39:54 +0200
Subject: the ultimate logging facility for debugging code
Message-ID: <4A570C6A.2060904@sequans.com>

Greetings,

Sorry for the dubious title :o). I was wandering if there is a standard 
(or reliable) python module that implements the following feature:

http://code.activestate.com/recipes/198078/
 >>>Recipe 198078: Wrapping method calls (meta-class example)
 >>>
 >>>A metaclass is used to wrap all (or just some) methods for logging 
purposes. The underlying mechanism can be used as well to check pre/post 
conditions, attribute access,... The basic point is, that the actual 
class must not be changed in any way to achive the desired effect.
   

I had to adapt the code to some of my needs, but now it's almost 
working, by simply defining a metaclass for any of my class, I get the 
class methods calls logged with the instance that called the method, the 
method name, the call line in the file, the parameter **value**  passed 
to the method and the returned value.
It just saved me from hours of ipython interactive debugging with the 
old print way, and to beauty of it: I don't have to write any 
"self._log('Please log me')" line.

As it is so useful, I bet there is a module that is doing this in a more 
reliable way that I did. Anyone has heard of it ?

Jean-Michel



From jhinak.sen at gmail.com  Fri Jul 10 05:41:03 2009
From: jhinak.sen at gmail.com (jhinak sen)
Date: Fri, 10 Jul 2009 15:11:03 +0530
Subject: help me to find the error
Message-ID: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>

hi,
i am a beginner in python language,

i am trying with this programme :
to find the addition and mean from a data set in a file and writing the mean
and sum in some other file :
""
*#! /usr/bin/env python

import re
import cPickle as p
import math
from numpy import *

f0= open("temp9","r+").readlines()
f2= open("out1","r+")
add_1=[ ];
for i in range(0, len(f0)):
        f1=f0[i].split()
        add= float(f1[1])+float(f1[2])
    mean= float(add)/2
        print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
repr(mean).ljust(7)
        add_1.append(add)
    add_1.append(mean)
        f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
repr(mean).ljust(7))
print "printing from file"
for i in range(0, len(add_1),2):
        print add_1[i],"        ", add_1[i+1]

f0.close()
f2.close()*


""

and this programme is givving me this error :

""    *Traceback (most recent call last):
  File "./temporary1.py", line 24, in <module>
    f0.close()
AttributeError: 'list' object has no attribute 'close'*
""

please help to to find the error.
or suggest some simpler or better way

note:
1)file "temp9" is already exist
2)this programme is giving me all my outputs, but at the end of the out
..its giving me that error.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/3145e82b/attachment.html>

From contact at xavierho.com  Fri Jul 10 05:53:15 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 10 Jul 2009 17:53:15 +0800
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <2d56febf0907100253m55cca65eo1889431de5b9835d@mail.gmail.com>

I'm new to Python myself, but I think it's because the method readlist()
returns a list. Hence, f0 is typed 'list'. And lists can't be closed.

If you leave it to:

*f0= open("temp9","r+")

*and then assign another variable to the readlist, such as:

*lines = f0.readlines()*

Then in the for loop, change f1 to

*f1=lines[i].split()*

That may just stop it from complaining.

Untested, but logically it's sound.

Hope that works,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Fri, Jul 10, 2009 at 5:41 PM, jhinak sen <jhinak.sen at gmail.com> wrote:

> hi,
> i am a beginner in python language,
>
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the
> mean and sum in some other file :
> ""
> *#! /usr/bin/env python
>
> import re
> import cPickle as p
> import math
> from numpy import *
>
> f0= open("temp9","r+").readlines()
> f2= open("out1","r+")
> add_1=[ ];
> for i in range(0, len(f0)):
>         f1=f0[i].split()
>         add= float(f1[1])+float(f1[2])
>     mean= float(add)/2
>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
> repr(mean).ljust(7)
>         add_1.append(add)
>     add_1.append(mean)
>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
> repr(mean).ljust(7))
> print "printing from file"
> for i in range(0, len(add_1),2):
>         print add_1[i],"        ", add_1[i+1]
>
> f0.close()
> f2.close()*
>
>
> ""
>
> and this programme is givving me this error :
>
> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""
>
> please help to to find the error.
> or suggest some simpler or better way
>
> note:
> 1)file "temp9" is already exist
> 2)this programme is giving me all my outputs, but at the end of the out
> ..its giving me that error.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/70ba34a7/attachment.html>

From gabriel.rossetti at arimaz.com  Fri Jul 10 05:57:23 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 10 Jul 2009 11:57:23 +0200
Subject: Threading.Condition problem
Message-ID: <4A571083.8030403@arimaz.com>

Hello everyone,

I wrote a small example that listens for xmpp msgs in a thread. The main 
program calls a function that blocks (using Condition.wait) until a msg 
has been received and then returns the msg. When a msg arrives, it is 
put in a variable in the thread's object, it then calls the notify() 
attr on the Condition object. For some reason, this doesn't work, the 
thread gets the msg, tries to notify the Condition object, fails because 
the lock has not been acquired yet and blocks. I tried ignoring the 
failure, thinking that since it has not been acquired yet then when it 
is, it will get the msg right away and never call Condition.wait, thus 
not causing any problems, but this does not work either. Does someone 
know what I am doing wrong? I attached the code to this msg.

Thank you,
Gabriel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: xmpp_client.py
Type: text/x-python
Size: 6127 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/1645640b/attachment.py>

From bearophileHUGS at lycos.com  Fri Jul 10 05:58:33 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 10 Jul 2009 02:58:33 -0700 (PDT)
Subject: psyco V2 beta2 benchmark
References: <h2nhhs$g5m$00$1@news.t-online.com>
Message-ID: <c795efdd-4a73-46f8-8a63-5e1d6c86e4c3@32g2000yqj.googlegroups.com>

larudwer, is that time_subdist subdist(i) a bad worsening? Something
to be fixed in Psyco2?

Bye,
bearophile


From sebastian.schabe at gmx.de  Fri Jul 10 06:01:51 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Fri, 10 Jul 2009 12:01:51 +0200
Subject: Concatenating images (numpy arrays), but they look like HSV images
In-Reply-To: <mailman.2909.1247162905.8015.python-list@python.org>
References: <4a5629ba$1@news.fhg.de>
	<mailman.2909.1247162905.8015.python-list@python.org>
Message-ID: <4a5710ea$1@news.fhg.de>

Robert Kern schrieb:
> Probably, you need to use zeros(..., dtype=uint8). When you use 
> dtype=int, that will result in dtype=int arrays. I suspect that 
> matplotlib is then interpreting that to mean that you want it to treat 
> the input as scalar data (which it will pass through a colormap) rather 
> than an RGB image.
> 

Thanks Robert, that was exactly the problem. Now I'am really wondering 
how one can know such details. Well, with your answer I searched again 
in the mathplotlib documentation and under the function imshow(X, ...) I 
indeed found the hint, that X has to be an uint8 or float array or PIL 
image, but before I hadn't known where to search.

So again, thank you

Sebastian


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 10 06:14:26 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 10 Jul 2009 12:14:26 +0200
Subject: property using a classmethod
In-Reply-To: <rTp5m.3784$ze1.643@news-server.bigpond.net.au>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
	<4a55e8e0$0$8041$426a34cc@news.free.fr>
	<rTp5m.3784$ze1.643@news-server.bigpond.net.au>
Message-ID: <4a571483$0$19592$426a74cc@news.free.fr>

Lie Ryan a ?crit :
> Bruno Desthuilliers wrote:
>> Lie Ryan a ?crit :
>>> Emanuele D'Arrigo wrote:
>> (snip)
>>>> Ultimately all I want is a non-callable class-level attribute
>>>> MyClass.myProperty that gives the result of MyClass.myClassMethod().
>>> This works like what you seem to want (it's ugly):
>> Ugly, indeed. And an extreme case of arbitrary overcomplexification too :-/
>>
>> (snip rube goldberg code)
>>
> 
> Can't think of anything simpler than that without meddling with
> descriptor.

Hmmm... Rereading the OP's spec, I guess you understood it better than I 
did - seems the OP wants to be able to call the "property" on the class 
object itself - which won't work with the builtin property type. So my 
own proposed solution won't do :-/

But still, "meddling with descriptor" is *way* simpler than your 
proposed solution. Here's a simple non-binding descriptor that do the job:

class ClsProperty(object):
     def __init__(self, fget):
         if not isinstance(fget, (classmethod, staticmethod)):
             raise ValueError(
               "fget must be a classmethod or staticmethod"
               )
         self.fget = fget

     def __get__(self, obj, cls=None):
         if cls is None:
             assert obj is not None
             cls = type(obj)
         return self.fget.__get__(obj, cls)()


# example use
class Foo(object):
     @classmethod
     def bar(cls):
         return "%s.bar" % cls.__name__

     quux = ClsProperty(bar)


> I'm not even sure descriptor can help here as it seems
> descriptor needs an instance?

wrt/ descriptors, no, they don't "need" an instance, at least for 
non-binding descriptors. Else, MyClass.MyMethod would return the 
MyClass.__dict__['MyMethod'] function, not an unbound method object !-)




From jhinak.sen at gmail.com  Fri Jul 10 06:20:47 2009
From: jhinak.sen at gmail.com (jhinak sen)
Date: Fri, 10 Jul 2009 15:50:47 +0530
Subject: Python-list Digest, Vol 70, Issue 142
In-Reply-To: <mailman.57.1247220004.18838.python-list@python.org>
References: <mailman.57.1247220004.18838.python-list@python.org>
Message-ID: <3d4ff96c0907100320s346403baga8795d0c61cd54d7@mail.gmail.com>

hey Xavier

thnx a lot :)
its working and ya.. i got your pont regarding typecasting .

jhinak

On Fri, Jul 10, 2009 at 3:30 PM, <python-list-request at python.org> wrote:

> Send Python-list mailing list submissions to
>        python-list at python.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
>        http://mail.python.org/mailman/listinfo/python-list
> or, via email, send a message with subject or body 'help' to
>        python-list-request at python.org
>
> You can reach the person managing the list at
>        python-list-owner at python.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Python-list digest..."
>
> Today's Topics:
>
>   1. A zlib question (Roland Hedberg)
>   2. Re: help me to find the error (Xavier Ho)
>   3. Re: Concatenating images (numpy arrays), but they look like
>      HSV images (Sebastian Schabe)
>
>
> ---------- Forwarded message ----------
> From: Roland Hedberg <roland at catalogix.se>
> To: python-list at python.org
> Date: Fri, 10 Jul 2009 11:33:25 +0200
> Subject: A zlib question
> Hi!
>
> I have a problem with zlib and compressing/decompressing according to RFC
> 1951.
>
> It seems like I can decompress, something compressed according to RFC 1951
> by someone else, provided I set wbits to something negative (used -8 but I
> guess any negative number would work?).
>
> But how can I compress using zlib so it doesn't add a gzip header ?
>
> -- Roland
>
>
> ---------- Forwarded message ----------
> From: Xavier Ho <contact at xavierho.com>
> To: python-list at python.org
> Date: Fri, 10 Jul 2009 17:53:15 +0800
> Subject: Re: help me to find the error
> I'm new to Python myself, but I think it's because the method readlist()
> returns a list. Hence, f0 is typed 'list'. And lists can't be closed.
>
> If you leave it to:
>
> *f0= open("temp9","r+")
>
> *and then assign another variable to the readlist, such as:
>
> *lines = f0.readlines()*
>
> Then in the for loop, change f1 to
>
> *f1=lines[i].split()*
>
> That may just stop it from complaining.
>
> Untested, but logically it's sound.
>
> Hope that works,
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
>
> On Fri, Jul 10, 2009 at 5:41 PM, jhinak sen <jhinak.sen at gmail.com> wrote:
>
>> hi,
>> i am a beginner in python language,
>>
>> i am trying with this programme :
>> to find the addition and mean from a data set in a file and writing the
>> mean and sum in some other file :
>> ""
>> *#! /usr/bin/env python
>>
>> import re
>> import cPickle as p
>> import math
>> from numpy import *
>>
>> f0= open("temp9","r+").readlines()
>> f2= open("out1","r+")
>> add_1=[ ];
>> for i in range(0, len(f0)):
>>         f1=f0[i].split()
>>         add= float(f1[1])+float(f1[2])
>>     mean= float(add)/2
>>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
>> repr(mean).ljust(7)
>>         add_1.append(add)
>>     add_1.append(mean)
>>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
>> repr(mean).ljust(7))
>> print "printing from file"
>> for i in range(0, len(add_1),2):
>>         print add_1[i],"        ", add_1[i+1]
>>
>> f0.close()
>> f2.close()*
>>
>>
>> ""
>>
>> and this programme is givving me this error :
>>
>> ""    *Traceback (most recent call last):
>>   File "./temporary1.py", line 24, in <module>
>>     f0.close()
>> AttributeError: 'list' object has no attribute 'close'*
>> ""
>>
>> please help to to find the error.
>> or suggest some simpler or better way
>>
>> note:
>> 1)file "temp9" is already exist
>> 2)this programme is giving me all my outputs, but at the end of the out
>> ..its giving me that error.
>>
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>
>>
>
>
> ---------- Forwarded message ----------
> From: Sebastian Schabe <sebastian.schabe at gmx.de>
> To: python-list at python.org
> Date: Fri, 10 Jul 2009 12:01:51 +0200
> Subject: Re: Concatenating images (numpy arrays), but they look like HSV
> images
> Robert Kern schrieb:
>
>> Probably, you need to use zeros(..., dtype=uint8). When you use dtype=int,
>> that will result in dtype=int arrays. I suspect that matplotlib is then
>> interpreting that to mean that you want it to treat the input as scalar data
>> (which it will pass through a colormap) rather than an RGB image.
>>
>>
> Thanks Robert, that was exactly the problem. Now I'am really wondering how
> one can know such details. Well, with your answer I searched again in the
> mathplotlib documentation and under the function imshow(X, ...) I indeed
> found the hint, that X has to be an uint8 or float array or PIL image, but
> before I hadn't known where to search.
>
> So again, thank you
>
> Sebastian
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/5e8c298d/attachment.html>

From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 10 06:38:49 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 10 Jul 2009 12:38:49 +0200
Subject: property using a classmethod
In-Reply-To: <4a55db9e$0$10243$426a74cc@news.free.fr>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<4a55db9e$0$10243$426a74cc@news.free.fr>
Message-ID: <4a571a39$0$29561$426a74cc@news.free.fr>

Bruno Desthuilliers a ?crit :
(snip)
> You could write your own custom descriptor. Or just use an additional 
> level of indirection, ie:
> 
>    myProperty = property(lambda self: self.myClassMethod())
> 

Sorry, looks like I didn't read carefully enough. The above code won't 
work if you intend to lookup the property directly on the class object, 
ie "MyClass.myProperty". If that was your intention, you'll need a 
custom descriptor. The following code should do the job, or at least get 
you started:

# python 2.5.x

# the custom (non binding) descriptor
class ClsProperty(object):
     def __init__(self, fget):
         if not isinstance(fget, (classmethod, staticmethod)):
             # XXX better error message
             raise ValueError(
               "fget must be a classmethod or staticmethod"
             )
         self.fget = fget

     def __get__(self, obj, cls=None):
         if cls is None:
             assert obj is not None
             cls = type(obj)
         return self.fget.__get__(obj, cls)()

# helper -> a simple decorator
def classproperty(func):
     if not isinstance(func, (classmethod, staticmethod)):
         func = classmethod(func)
     return ClsProperty(func)


# example use
class Foo(object):

     # the hard way
     @classmethod
     def bar(cls):
         return "%s.bar" % cls.__name__

     quux = ClsProperty(bar)

     # the simple way
     @classproperty
     def baaz(cls):
         return "%s.baaz" % cls


Given your example, this should be enough. If you need a binding 
descriptor (one with a setter), you'll have to implement the __set__ 
method (and possibly __del__). Google for "python descriptor" to find 
more doc about the descriptor protocol.

HTH


From mail at microcorp.co.za  Fri Jul 10 06:54:21 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 10 Jul 2009 12:54:21 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <001401ca014c$ca414d60$0d00a8c0@Hendrik>

"Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:

>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>
>>> persistent idea "out there" that programming is a very accessible
>>> skill, like cooking or gardening, anyone can do it, and even profit
>>> from it, monetarily or otherwise, etc., and to some extent I am
>> 
>> Programming is not like any other human activity.
>
>In practice? In principle? Programming in principle is not the same as it 
>is performed in practice.
>
>But in either case, programming requires both the logical reasoning of 
>mathematics and the creativity of the arts. Funnily enough, 

I do not buy this arty creativity stuff. - or are you talking about
making a website look pretty?

>mathematicians will tell you that mathematics requires the same, and so 
>will the best artists. I think mathematicians, engineers, artists, even 
>great chefs, will pour scorn on your claim that programming is not like 
>any other human activity.

So a chef is now an authority on programming?

Programming is actually kind of different - almost everything else is 
just done, at the time that you do it.

Programming is creating stuff that is completely useless until it is
fed into something that uses it, to do something else, in conjuction
with the thing it is fed into, at a later time.

This is a highly significant difference, IMHO.


>
>
>[...]
>> He talks about how "when all is said and done, the only thing computers
>> can do for us is to manipulate symbols and produce results of such
>> manipulations" and he emphasises the "uninterpreted" nature of
>> mechanical symbol manipulation, i.e. that the machine is doing it
>> mindlessly.
>
>"Manipulate symbols" is so abstract as to be pointless. By that 
>reasoning, I can build a "computer" consisting of a box open at the top. 
>I represent a symbol by an object (say, a helium-filled balloon, or a 
>stone), instead of a pattern of bits. I manipulate the symbol by holding 
>the object over the box and letting go. If it flies up into the sky, that 
>represents the symbol "Love is War", if it falls into the box, it 
>represents the symbol "Strength is Blue", and if it just floats there, it 
>represents "Cheddar Cheese". This is a deterministic, analog computer 
>which manipulates symbols. Great.
>
>And utterly, utterly useless. So what is my computer lacking that real 
>computers have? When you have answered that question, you'll see why 
>Dijkstra's claim is under-specified.
>

So if computers do not manipulate symbols, what is it that they do?
They sure cannot think,
or drink,
or reason,
or almost any verb you can think of.

"Manipulating symbols" is actually an elegant definition.
Try coming up with a better one and you will see.

And calling an abstraction pointless kind of contradicts
what you say later...

8<------- camel humps and other stuff -------------------

- Hendrik





From gabriel.rossetti at arimaz.com  Fri Jul 10 07:09:28 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 10 Jul 2009 13:09:28 +0200
Subject: Threading.Condition problem
In-Reply-To: <4A571083.8030403@arimaz.com>
References: <4A571083.8030403@arimaz.com>
Message-ID: <4A572168.90201@arimaz.com>

The previous msg w/ attached code is the wrong code, please use the code 
attached to this msg, thank you and sorry for this.

Gabriel


Gabriel Rossetti wrote:
> Hello everyone,
>
> I wrote a small example that listens for xmpp msgs in a thread. The 
> main program calls a function that blocks (using Condition.wait) until 
> a msg has been received and then returns the msg. When a msg arrives, 
> it is put in a variable in the thread's object, it then calls the 
> notify() attr on the Condition object. For some reason, this doesn't 
> work, the thread gets the msg, tries to notify the Condition object, 
> fails because the lock has not been acquired yet and blocks. I tried 
> ignoring the failure, thinking that since it has not been acquired yet 
> then when it is, it will get the msg right away and never call 
> Condition.wait, thus not causing any problems, but this does not work 
> either. Does someone know what I am doing wrong? I attached the code 
> to this msg.
>
> Thank you,
> Gabriel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: test_xmpp.py
Type: text/x-python
Size: 1878 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/e8c8f701/attachment.py>

From gabriel.rossetti at arimaz.com  Fri Jul 10 07:09:42 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 10 Jul 2009 13:09:42 +0200
Subject: Threading.Condition problem
Message-ID: <4A572176.9070100@arimaz.com>

Sorry if this appears twice, I sent it once with an attachment and it 
never arrived so maybe the attachment is posing problems. I inlined the 
code this time (at the bottom), thank you,

Gabriel

########################## Original message ############################

Hello everyone,

I wrote a small example that listens for xmpp msgs in a thread. The main
program calls a function that blocks (using Condition.wait) until a msg
has been received and then returns the msg. When a msg arrives, it is
put in a variable in the thread's object, it then calls the notify()
attr on the Condition object. For some reason, this doesn't work, the
thread gets the msg, tries to notify the Condition object, fails because
the lock has not been acquired yet and blocks. I tried ignoring the
failure, thinking that since it has not been acquired yet then when it
is, it will get the msg right away and never call Condition.wait, thus
not causing any problems, but this does not work either. Does someone
know what I am doing wrong? I attached the code to this msg.

Thank you,
Gabriel



############################ Example code ############################

from __future__ import with_statement
import xmpp, sys
from threading import Thread, Condition, Event


class Listener(Thread):
     def __init__(self, ws):
         Thread.__init__(self)
         self.interrupt = Event()
         self.message = None
         self._cv = ws._cv
         self.client = ws._client
         self.client.RegisterHandler('message', self.onMessage)

     def onMessage(self, conn, msg):
         self.message = msg
         try:
             self._cv.notify()
         except RuntimeError:
             print "self._cv has not acquired the lock yet"

     def getMsg(self):
         return self.message

     def run(self):
         try:
             while(not self.interrupt.isSet()):
                 self.client.Process(1)
         except KeyboardInterrupt:
             return 0

class WS(object):
     def __init__(self, username, password, res):
         self._jid = xmpp.protocol.JID(username)
         self._client = xmpp.Client(self._jid.getDomain())
         self._cv = Condition()

         if(self._client.connect(server=("localhost", 5222)) == ""):
             raise Exception("Error while connecting!")

         if(self._client.auth(self._jid.getNode(), password, res) is None):
             raise Exception("Authentication failed!")

         self._client.sendInitPresence()

         self._listener = Listener(self)
         self._listener.start()

     def getMsg(self, mid=None):
         """
         """
         with self._cv:
             res = self._listener.getMsg()
             while not res:
                 self._cv.wait()
                 res = self._listener.getMsg()
             return res

if(__name__ == "__main__"):
     ws = WS("test at localhost", "123", "test")
     res = ws.getMsg()
     print "I just received : %s" % str(res)
     sys.exit(0)




From ben+python at benfinney.id.au  Fri Jul 10 07:30:41 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 10 Jul 2009 21:30:41 +1000
Subject: subprocess + python-daemon - bug/problem?
References: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>
	<828acd8d-a9bd-4506-b695-e537af4587d8@l31g2000yqb.googlegroups.com>
Message-ID: <873a94ojvi.fsf@benfinney.id.au>

Andy  Clegg <andy2.0 at gmail.com> writes:

> "import daemon
> import subprocess
> 
> daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
> subprocess.Popen(['echo','1']).wait()"
> 
> However the error remains the same.

The error appears in the file specified for the stderr output of the
DaemonContext. Here it is without the unwanted extra line-wrapping that
seems to plague all Google Mail users (seriously, folks: get a real mail
provider that won't mangle your messages)::

    Traceback (most recent call last):
      File "/home/bignose/Projects/python/python-daemon/bin/andy-clegg-test", line 7, in <module>
        subprocess.Popen(['echo', '1']).wait()
      File "/usr/lib/python2.5/subprocess.py", line 1184, in wait
        pid, sts = self._waitpid_no_intr(self.pid, 0)
      File "/usr/lib/python2.5/subprocess.py", line 1014, in _waitpid_no_intr
        return os.waitpid(pid, options)
    OSError: [Errno 10] No child processes

I confirm that I'm getting the same error; Python 2.5.4.

My first thought was perhaps it's related to the fact that the process
has no stdout? But setting ?stdout? and ?stderr? to the same file::

    #! /usr/bin/python

    import daemon
    import subprocess

    fake_console = open("fake_console.txt", "w+")
    daemon.DaemonContext(stdout=fake_console, stderr=fake_console).open()
    subprocess.Popen(['echo', '1']).wait()

still gives the same error::

    1
    Traceback (most recent call last):
      File "/home/bignose/Projects/python/python-daemon/bin/andy-clegg-test", line 8, in <module>
        subprocess.Popen(['echo', '1']).wait()
      File "/usr/lib/python2.5/subprocess.py", line 1184, in wait
        pid, sts = self._waitpid_no_intr(self.pid, 0)
      File "/usr/lib/python2.5/subprocess.py", line 1014, in _waitpid_no_intr
        return os.waitpid(pid, options)
    OSError: [Errno 10] No child processes

I'm not familiar enough with the nuances of the ?subprocess? module to
know what might be going wrong here. I'd like to know whether it might
be a problem in the ?python-daemon? library.

-- 
 \     ?Whatever a man prays for, he prays for a miracle. Every prayer |
  `\   reduces itself to this: ?Great God, grant that twice two be not |
_o__)                                           four.?? ?Ivan Turgenev |
Ben Finney


From vox2000 at gmail.com  Fri Jul 10 07:46:52 2009
From: vox2000 at gmail.com (vox)
Date: Fri, 10 Jul 2009 04:46:52 -0700 (PDT)
Subject: Query regarding set([])?
Message-ID: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>

Hi,
I'm contsructing a simple compare-script and thought I would use set
([]) to generate the difference output. But I'm obviosly doing
something wrong.

file1 contains 410 rows.
file2 contains 386 rows.
I want to know what rows are in file1 but not in file2.

This is my script:
s1 = set(open("file1"))
s2 = set(open("file2"))
s3 = set([])
s1temp = set([])
s2temp = set([])

s1temp = set(i.strip() for i in s1)
s2temp = set(i.strip() for i in s2)
s3 = s1temp-s2temp

print len(s3)

Output is 119. AFAIK 410-386=24. What am I doing wrong here?

BR,
Andy


From davea at ieee.org  Fri Jul 10 07:48:49 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 07:48:49 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <h35a1h$gus$1@ger.gmane.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>	<4A55F392.3080404@ieee.org>
	<h35a1h$gus$1@ger.gmane.org>
Message-ID: <4A572AA1.7010207@ieee.org>

Terry Reedy wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
>> m.reddy prasad reddy wrote:
>>> can any one tell me how to write assembly language programs in 
>>> python...if
>>> no is there any other way to write the programs in python
>>>
>>> Reddi prasad reddy
>>> ph.no:09958083797
>>>
>>>   
>> Assembly language is a different programming language than Python.  
>> You can use both in the same process, much in the same way you can 
>> use C or C++ with Python.  In fact, some of the system DLL's are 
>> written (partly) in assembler, though mostly in C or C++.
>
> It is possible that he meant how to write assembly *with* python.
> Or how to translate python to assembly.
>
> As it turns out, CPython translates Python to byte code and has a dis 
> (assembly) module that produces very nice assembly code ;-)
> So that is one answer to his question.
>
>> You'll need to tell us what your real goal is.
>
> Definitely.
>
> tjr
>
>
> </div>
>
If you mean dis.dis() that only gives you byte code.  I assumed he was 
referring to native code assembly.

I guess I'd better stop guessing <grin>.

DaveA



From __peter__ at web.de  Fri Jul 10 08:04:35 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 14:04:35 +0200
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
Message-ID: <h37aod$i9p$02$1@news.t-online.com>

vox wrote:

> I'm contsructing a simple compare-script and thought I would use set
> ([]) to generate the difference output. But I'm obviosly doing
> something wrong.
> 
> file1 contains 410 rows.
> file2 contains 386 rows.
> I want to know what rows are in file1 but not in file2.
> 
> This is my script:
> s1 = set(open("file1"))
> s2 = set(open("file2"))

Remove the following three lines:

> s3 = set([])
> s1temp = set([])
> s2temp = set([])

 
> s1temp = set(i.strip() for i in s1)
> s2temp = set(i.strip() for i in s2)
> s3 = s1temp-s2temp
> 
> print len(s3)
> 
> Output is 119. AFAIK 410-386=24. What am I doing wrong here?

You are probably misinterpreting len(s3). s3 contains lines occuring in 
"file1" but not in "file2". Duplicate lines are only counted once, and the 
order doesn't matter. 

So there are 119 lines that occur at least once in "file2", but not in 
"file1".

If that is not what you want you have to tell us what exactly you are 
looking for.

Peter



From paul at boddie.org.uk  Fri Jul 10 08:07:21 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Fri, 10 Jul 2009 05:07:21 -0700 (PDT)
Subject: psyco V2 beta2 benchmark
References: <h2nhhs$g5m$00$1@news.t-online.com>
	<mailman.2930.1247194493.8015.python-list@python.org>
Message-ID: <35dcc79b-4f9d-4f16-942e-7cee2a470844@t13g2000yqt.googlegroups.com>

On 10 Jul, 04:54, Zac Burns <zac... at gmail.com> wrote:
> Where do you get this beta? I heard that Psyco V2 is coming out but
> can't find anything on their site to support this.

I found the Subversion repository from the Psyco site:

http://psyco.sourceforge.net/

-> http://codespeak.net/svn/psyco/dist/

-> http://codespeak.net/svn/psyco/v2/

It's not widely advertised, but I imagine that this is the correct
repository. Navigating around on the codespeak.net site took me to the
ViewVC instance which gives some date/time information that would
confirm my suspicions:

https://codespeak.net/viewvc/psyco/

A log of the development can be viewed here:

https://codespeak.net/viewvc/psyco/v2/dist/?view=log

Paul


From mondi at cs.unibo.it  Fri Jul 10 08:10:04 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Fri, 10 Jul 2009 12:10:04 +0000
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <mailman.2929.1247192119.8015.python-list@python.org>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
Message-ID: <h373dq$hpn$1@lec.cs.unibo.it>

Roger Binns wrote:
> jacopo mondi wrote:
>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>> add support to an experimental socket family.
> 
> You may find it considerably easier to use ctypes since that will avoid
> the need for any patching.  You'll also be able to control how read and
> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
> os.fdopen to convert your raw file descriptor into a Python file object
> if appropriate.
> 
> If you do use ctypes then you'll only need to distribute pure Python
> source code.
> 
> Roger
Thanks a lot, I'll give it a try..

cheers
	jacopo


From rhodri at wildebst.demon.co.uk  Fri Jul 10 08:22:31 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 10 Jul 2009 13:22:31 +0100
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <op.uwupztjca8ncjz@gnudebst>

On Fri, 10 Jul 2009 10:41:03 +0100, jhinak sen <jhinak.sen at gmail.com>  
wrote:

> hi,
> i am a beginner in python language,
>
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the  
> mean
> and sum in some other file :
> ""
> *#! /usr/bin/env python
>
> import re
> import cPickle as p
> import math
> from numpy import *
>
> f0= open("temp9","r+").readlines()
> f2= open("out1","r+")
> add_1=[ ];
> for i in range(0, len(f0)):
>         f1=f0[i].split()
>         add= float(f1[1])+float(f1[2])
>     mean= float(add)/2
>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
> repr(mean).ljust(7)
>         add_1.append(add)
>     add_1.append(mean)
>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
> repr(mean).ljust(7))
> print "printing from file"
> for i in range(0, len(add_1),2):
>         print add_1[i],"        ", add_1[i+1]
>
> f0.close()
> f2.close()*
>
>
> ""
>
> and this programme is givving me this error :
>
> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""

As the error message tells you, 'f0' is a list.  readlines()
returns a list of the lines in the file object, rather than the
file object itself.  Since you promptly (and entirely reasonably)
discard the file object, you haven't got any way to close() it.

You don't actually need to do that, though.  You can use a file
object as something you use a 'for' loop over, and be given one
line at a time.  So instead you can write your code like this:

<snippet>
f0 = open("temp9", "r")
for line in f0:
     f1 = line.split()
     # ... and so on
</snippet>

Notice that I only opened the file as "r" -- you are only
reading it, not updating it, and giving yourself more permission
than you need is a bad habit to get into.  Opening the file this
way means that if you accidentally write f0.write("something")
instead of "f2.write(something)", Python will stop you with an
exception rather than silently trash your data.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Fri Jul 10 08:25:49 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 10 Jul 2009 13:25:49 +0100
Subject: need to write a assembly progrm
In-Reply-To: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
References: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
Message-ID: <op.uwup5bama8ncjz@gnudebst>

On Thu, 09 Jul 2009 11:52:44 +0100, m.reddy prasad reddy  
<reddy.mrp at gmail.com> wrote:

> my aim is to run the assembly programs in python.by that we can use that  
> in
> the any labs.because we can run the python in the mobiles also.if we  
> write
> assembly programs in the mobile ,the mobile act as a tool kit for the
> lab.tell me any other solutions for this

Please define what you mean by "assembly".

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From mtnbikingmark at gmail.com  Fri Jul 10 08:30:46 2009
From: mtnbikingmark at gmail.com (Mark)
Date: Fri, 10 Jul 2009 05:30:46 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
	<d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com> 
	<ff67eeab-48d1-40a5-8870-666944c8c7f2@q11g2000yqi.googlegroups.com> 
	<d6bc18b8-f74e-40cb-ba9f-1be8386f2fc6@s31g2000yqs.googlegroups.com>
Message-ID: <3aa3398a-b944-40fc-bb3b-2c2650d41454@26g2000yqk.googlegroups.com>

Hi,

I am the author of pywinauto (http://pywinauto.openqa.org/).

It doesn't have specific functionality built in for winforms - but
many winforms controls are built on top of win32 functionality and
pywinauto can work with them for that.

On Jul 9, 4:41?pm, Paul McGuire <pt... at austin.rr.com> wrote:
> On Jul 9, 1:50?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
>
> > > I have used pywinauto to drive a Flash game running inside of an
> > > Internet Explorer browser - that's pretty GUI!
>

Wow - cool :)


> > > -- Paul
>
> > Hi,
>
> > Could you share some code examples?
>

You might have a look at http://pywinauto.pbworks.com/ (the site is no
longer used - but there is a cool movie giving an example of using
pywinauto at the interactive prompt)

Other examples (Notepad, mspaint) are included with the install.

PyPi - http://pypi.python.org/pypi/pywinauto/0.3.8


> > Thanks,
> > Duane (duanek (at) chorus (dot) net)
>

Good luck! :)
  Mark

> I just went on a brief fishing expedition through two disk backups,
> and no luck. ?I guess it's been a while since I worked on this.
>
> The work I did was entirely graphical, which is to say, my script
> interacted with the Flash program by using PIL to take image snapshots
> of the window, and then sifting through the bitmap looking for the
> status of a "time remaining" thermometer-style gauge in the game.
> Then the script could click on X-Y coordinates within the window,
> which would get picked up by the Flash game, and the script would
> monitor the "time remaining" gauge some more, and so on.
>
> I'm not sure how well pywinauto would work in allowing you to access
> controls such as textboxes within a form. ?I remember that I had to
> access the IE window using a caption name, and then found the embedded
> Flash program as an embedded control of some sort, again, I probably
> needed to indicate that it was some sort of "Adobe.FlashWidget1"
> object or something.
>
> I may have another, older disk backup at home, I can look for it later
> this evening.
>
> -- Paul



From jeanmichel at sequans.com  Fri Jul 10 08:32:52 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 10 Jul 2009 14:32:52 +0200
Subject: language analysis to enforce code standards
In-Reply-To: <pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
References: <mailman.9989.1246930194.8014.python-list@python.org>	<mailman.2927.1247192026.8015.python-list@python.org>
	<pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A5734F4.7010105@sequans.com>

Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 02:06:35 +0000, Jason S. Friedman wrote:
>
>   
>> Hello, I administer the Informatica ETL tool at my company.  Part of
>> that role involves creating and enforcing standards.  I want the
>> Informatica developers to add comments to certain key objects and I want
>> to be able to verify (in an automated fashion) that they have done so.
>>
>> I cannot merely check for non-emptiness; that is trivial to circumvent.
>>   On the other hand, I probably do not need to be able to catch
>> developers who are determined to not create comments.  There are not too
>> many of them and perhaps they will find it is easier to write a (useful)
>> comment than to game the system.
>>
>> Any thoughts on how I might proceed?  Stated plainly, how can I tell
>> when a string more-or-less forms at least one phrase?
>>     
>
> Define "phrase".
>
>
> if len(s) > 0:
>     print "at least one character"
> if len(s.split()) > 0:
>     print "at least one word"
> if len(s.split('\n') > 0:
>     print "at least one line"
>
>
>
>   
You could also verify there are at least N different characters used in 
the sentence:

N = 5 # must contains at least 5 different characters
record = []
for c in s:
    if c not in record:
        record += [c]
if len(record) >= N:
    print "at least %s different characters" % N


Jean-Michel


From python.list at tim.thechases.com  Fri Jul 10 08:37:59 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 10 Jul 2009 07:37:59 -0500
Subject: can i write a assemly language programs in python
In-Reply-To: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <4A573627.8090308@tim.thechases.com>

m.reddy prasad reddy wrote:
> can any one tell me how to write assembly language programs in python...if
> no is there any other way to write the programs in python

Bah, writing assembly language is easy in Python:

   print("MOV EAX, [EBX]")
   print("XOR EBX, EBX")

Just adjust the strings for your favorite processor architecture 
and Python will produce the assembly code you want.

Now compiling assembly to *machine* code...or calling between 
Python and assembly...that's another matter.  But writing 
assembly language programs in Python?  Easy. ;-)

-tkc





From __peter__ at web.de  Fri Jul 10 08:48:18 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 14:48:18 +0200
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
Message-ID: <h37dac$cfk$00$1@news.t-online.com>

Jason S. Friedman wrote:

> Hello, I administer the Informatica ETL tool at my company.  Part of
> that role involves creating and enforcing standards.  I want the
> Informatica developers to add comments to certain key objects and I want
> to be able to verify (in an automated fashion) that they have done so.
> 
> I cannot merely check for non-emptiness; that is trivial to circumvent.
>   On the other hand, I probably do not need to be able to catch
> developers who are determined to not create comments.  There are not too
> many of them and perhaps they will find it is easier to write a (useful)
> comment than to game the system.
> 
> Any thoughts on how I might proceed?  Stated plainly, how can I tell
> when a string more-or-less forms at least one phrase?

Don't be a fool. Have someone other than the author read the comment.

Peter



From vox2000 at gmail.com  Fri Jul 10 08:52:10 2009
From: vox2000 at gmail.com (vox)
Date: Fri, 10 Jul 2009 05:52:10 -0700 (PDT)
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
Message-ID: <3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>

On Jul 10, 2:04?pm, Peter Otten <__pete... at web.de> wrote:
> You are probably misinterpreting len(s3). s3 contains lines occuring in
> "file1" but not in "file2". Duplicate lines are only counted once, and the
> order doesn't matter.
>
> So there are 119 lines that occur at least once in "file2", but not in
> "file1".
>
> If that is not what you want you have to tell us what exactly you are
> looking for.
>
> Peter

Hi,
Thanks for the answer.

I am looking for a script that compares file1 and file2, for each line
in file1, check if line is present in file2. If the line from file1 is
not present in file2, print that line/write it to file3, because I
have to know what lines to add to file2.

BR,
Andy





From drobinow at gmail.com  Fri Jul 10 09:10:14 2009
From: drobinow at gmail.com (David Robinow)
Date: Fri, 10 Jul 2009 09:10:14 -0400
Subject: Query regarding set([])?
In-Reply-To: <3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
Message-ID: <4eb0089f0907100610j3c53f4efjae119c9ec21f3992@mail.gmail.com>

On Fri, Jul 10, 2009 at 8:52 AM, vox<vox2000 at gmail.com> wrote:
> I am looking for a script that compares file1 and file2, for each line
> in file1, check if line is present in file2. If the line from file1 is
> not present in file2, print that line/write it to file3, because I
> have to know what lines to add to file2.
  Just copy file1 to file2.
(I'm pretty sure that's not what you want, but in explaining why it
should become clearer what you're trying to do.)


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 09:11:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 13:11:09 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
Message-ID: <007318de$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 12:54:21 +0200, Hendrik van Rooyen wrote:

> "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
> 
>>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>>
>>>> persistent idea "out there" that programming is a very accessible
>>>> skill, like cooking or gardening, anyone can do it, and even profit
>>>> from it, monetarily or otherwise, etc., and to some extent I am
>>> 
>>> Programming is not like any other human activity.
>>
>>In practice? In principle? Programming in principle is not the same as
>>it is performed in practice.
>>
>>But in either case, programming requires both the logical reasoning of
>>mathematics and the creativity of the arts. Funnily enough,
> 
> I do not buy this arty creativity stuff. - or are you talking about
> making a website look pretty?

I must admit, it never crossed my mind that anyone here would claim that 
there was no creativity involved in programming, that it was all a 
mindless, algorithmic process capable of being done by a simple 
mechanical device.

This is certainly the accusation made against *bad* programmers -- that 
they can't actually solve new, unique problems, but just apply recipes 
they learned without any insight or intelligence. The sort of people who 
program so poorly that "a trained monkey could do what they do".

Do you really think that applies to good programmers too? If so, then a 
good code generator should be able to replace any programmer. Is that 
what you believe?


 
>>mathematicians will tell you that mathematics requires the same, and so
>>will the best artists. I think mathematicians, engineers, artists, even
>>great chefs, will pour scorn on your claim that programming is not like
>>any other human activity.
> 
> So a chef is now an authority on programming?

Did I say that?

Chefs are authorities on OTHER HUMAN ACTIVITIES.



> Programming is actually kind of different - almost everything else is
> just done, at the time that you do it.
> 
> Programming is creating stuff that is completely useless until it is fed
> into something that uses it, to do something else, in conjuction with
> the thing it is fed into, at a later time.

Somebody should teach Hendrik that human beings have been creating TOOLS 
for hundreds of thousands of years. People have been creating tools to 
build tools for thousands of years. Software is just more of the same.

Even *soup stock* fits the same profile as what Hendrik claims is almost 
unique to programming. On its own, soup stock is totally useless. But you 
make it, now, so you can you feed it into something else later on.

Or instant coffee.

No, Henrik, if that's the best you can do, it's not very good. It is 
rather sad, but also hilarious, that the most different thing you have 
noticed about software is that it's just like instant coffee.


> This is a highly significant difference, IMHO.


>>[...]
>>> He talks about how "when all is said and done, the only thing
>>> computers can do for us is to manipulate symbols and produce results
>>> of such manipulations" and he emphasises the "uninterpreted" nature of
>>> mechanical symbol manipulation, i.e. that the machine is doing it
>>> mindlessly.
>>
>>"Manipulate symbols" is so abstract as to be pointless. By that
>>reasoning, I can build a "computer" consisting of a box open at the top.
>>I represent a symbol by an object (say, a helium-filled balloon, or a
>>stone), instead of a pattern of bits. I manipulate the symbol by holding
>>the object over the box and letting go. If it flies up into the sky,
>>that represents the symbol "Love is War", if it falls into the box, it
>>represents the symbol "Strength is Blue", and if it just floats there,
>>it represents "Cheddar Cheese". This is a deterministic, analog computer
>>which manipulates symbols. Great.
>>
>>And utterly, utterly useless. So what is my computer lacking that real
>>computers have? When you have answered that question, you'll see why
>>Dijkstra's claim is under-specified.
>>
>>
> So if computers do not manipulate symbols, what is it that they do?

Did I say they don't manipulate symbols?


> They
> sure cannot think,
> or drink,
> or reason,

They can't reason? Then what are they doing when they manipulate symbols?

Yet again, it didn't even cross my mind that somebody would make this 
claim. My entire point is that it's not enough to just "manipulate 
symbols", you have to manipulate symbols the correct way, following laws 
of logic, so that the computer can *mindlessly* reason.


> or almost any verb you can think of.

If you're going to take that argument, then I'll remind you that there 
are no symbols inside a computer. There are only bits. And in fact, there 
aren't even any bits -- there are only analog voltages, and analog 
magnetic fields.


> "Manipulating symbols" is actually an elegant definition. Try coming up
> with a better one and you will see.

As I said above, it's not enough to just manipulate symbols. Here's a set 
of rules to manipulate symbols:

X => 0

or in English, "Any symbol becomes the zero symbol".

That's symbol manipulation. Utterly useless. This is why it's not enough 
to just manipulate symbols, you have to manipulate them THE RIGHT WAY.



-- 
Steven


From david250 at videotron.ca  Fri Jul 10 09:14:50 2009
From: david250 at videotron.ca (David Bernier)
Date: Fri, 10 Jul 2009 09:14:50 -0400
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <h37esb0ng0@news7.newsguy.com>

Musatov wrote:
> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan.  The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
> the results of other Google users immediately results in a level of
> accuracy and relevance above and beyond Google." Google changed their
> API following the launch or MeAmI.org and explored the possibility of
> blocking site access from MeAmI.org to Google search results but was
> unable to do so. Critics of MeAmI.org say what it is doing is
> tantamount to intellectual theft. When asked about this topper Musatov
> exclaimed, "The Internet was made for people, not companies." An
> analyst at Goldman Sachs says, requesting to remain anonymous,
> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> global activism and to tell you the truth, this makes it much more
> likely an acquisition target than potential intellectual property
> violator." Google could not be reached for comment.

Mr. Musatov, is it you who removed the post
quoted above from the Google Groups archive?

Thank you.

David Bernier


From Nikolaus at rath.org  Fri Jul 10 09:22:29 2009
From: Nikolaus at rath.org (Nikolaus Rath)
Date: Fri, 10 Jul 2009 09:22:29 -0400
Subject: Implementing a cache
Message-ID: <87ab3cwu3u.fsf@vostro.rath.org>

Hello,

I want to implement a caching data structure in Python that allows me
to:

 1. Quickly look up objects using a key
 2. Keep track of the order in which the objects are accessed (most
    recently and least recently accessed one, not a complete history)
 3. Quickly retrieve and remove the least recently accessed object.


Here's my idea for the implementation:

The objects in the cache are encapsulated in wrapper objects:

class OrderedDictElement(object):
    __slots__ = [ "next", "prev", "key", "value" ]

These wrapper objects are then kept in a linked lists and in an ordinary
dict (self.data) in parallel. Object access then works as follows:

    def __setitem__(self, key, value):
        if key in self.data:
            # Key already exists, just overwrite value
            self.data[key].value = value
        else:
            # New key, attach at head of list
            with self.lock:
                el = OrderedDictElement(key, value, next=self.head.next, prev=self.head)
                self.head.next.prev = el
                self.head.next = el
                self.data[key] = el

    def __getitem__(self, key):
        return self.data[key].value
    
To 'update the access time' of an object, I use
    
    def to_head(self, key):
        with self.lock:
            el = self.data[key]
            # Splice out
            el.prev.next = el.next
            el.next.prev = el.prev
            
            # Insert back at front
            el.next = self.head.next
            el.prev = self.head
            
            self.head.next.prev = el
            self.head.next = el
        

self.head and self.tail are special sentinel objects that only have a
.next and .prev attribute respectively.


While this is probably going to work, I'm not sure if its the best
solution, so I'd appreciate any comments. Can it be done more elegantly?
Or is there an entirely different way to construct the data structure
that also fulfills my requirements?


I already looked at the new OrderedDict class in Python 3.1, but
apparently it does not allow me to change the ordering and is therefore
not suitable for my purpose. (I can move something to one end by
deleting and reinserting it, but I'd like to keep at least the option of also
moving objects to the opposite end).


Best,


   -Nikolaus

-- 
 ?Time flies like an arrow, fruit flies like a Banana.?

  PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6  02CF A9AD B7F8 AE4E 425C


From aahz at pythoncraft.com  Fri Jul 10 09:50:29 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 06:50:29 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32eoh$ql8$1@reader1.panix.com>
	<h32fon$264$1@panix3.panix.com> <h32i2o$eop$1@reader1.panix.com>
Message-ID: <h37gv5$r81$1@panix3.panix.com>

[excessive quoting ahead, I'm too tired to trim]

In article <h32i2o$eop$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>In <h32fon$264$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:
>>In article <h32eoh$ql8$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>>
>>>OK, so, scratching from my original post the case
>>>
>>><identifier>.<identifier> = <expression>
>>>
>>>(as being a special case of <identifier> = <expression>), still,
>>>to the extent that I understand your post, the "=" in
>>>
>>>  x = 1
>>>
>>>means something fundamentally different (in terms of Python's
>>>underlying implementation) from the "=" in
>>>
>>>  y[0] = 1
>>>
>>>No?
>>
>>No.  ;-)
>
>No???  Just when I thought I finally understood all this!
>
>>What's different is not the ``=`` but the construction of the
>>assignment target before ``=`` gets executed.
>
>Hmm.  OK, I went to the link you posted in your other message
>(http://docs.python.org/reference/simple_stmts.html#assignment-statements)
>and I find this (my emphasis):
>
>    Assignment of an object to a single target is recursively defined as follows.
>
>    * If the target is an identifier (name):
>
>	  o If the name does not occur in a global statement in
>	    the current code block: the name is bound to the object
>                                    ^^^^^^^^^^^^^^^^^
>	    in the current local namespace.
>
>	  o Otherwise: the name is bound to the object in the
>                       ^^^^^^^^^^^^^^^^^
>	    current global namespace.
>
>      The name is rebound if it was already bound. This may cause
>      the reference count for the object previously bound to the
>      name to reach zero, causing the object to be deallocated and
>      its destructor (if it has one) to be called.
>
>    * If the target is a target list enclosed in parentheses or in
>      square brackets... (I'LL IGNORE THIS FOR NOW)
>
>    * If the target is an attribute reference: The primary expression
>      in the reference is evaluated. It should yield an object with
>      assignable attributes; if this is not the case, TypeError is
>      raised. That object is then asked to assign the assigned
>              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      object to the given attribute; if it cannot perform the
>      ^^^^^^
>      assignment, it raises an exception (usually but not necessarily
>      AttributeError).
>
>    * If the target is a subscription: The primary expression in
>      the reference is evaluated. It should yield either a mutable
>      sequence object (such as a list) or a mapping object (such
>      as a dictionary). Next, the subscript expression is evaluated.
>
>      If the primary is a mutable sequence object (such as a
>      list),...  [CONDITIONS ON THE INDEX EXPRESSION OMITTED]...
>      the sequence is asked to assign the assigned object to its
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      item with that index....
>
>      If the primary is a mapping object (such as a dictionary),...
>      [CONDITIONS ON THE SUBSCRIPT EXPRESSION OMITTED]... the
>                                                          ^^^
>      mapping is then asked to create a key/datum pair which maps
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      the subscript to the assigned object.
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>    * If the target is a slicing: [INDEX STUFF OMITTED]... the
>                                                           ^^^
>      sequence object is asked to replace the slice with the items
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      of the assigned sequence...
>      ^^^^^^^^^^^^^^^^^^^^^^^^
>
>OK, I originally interpreted what Lundh wrote in his two articles
>that the "binding" described at the very beginning (i.e. when the
>target is an identifier), which I take to make an entry or modify
>such an entry in a namespace, is a *categorically different*
>operation from the remaining operations underlined above.
>
>I interpreted Paul Boddie's correction in his response to me as
>saying that the "assignment" mentioned for the case when the target
>is an attribute reference is actually a special case of the
>"assignment" to simple identifiers (i.e. it also means "binding").
>
>But that still leaves all the other "assignments" (or the like)
>underlined above.  I don't think that the full definitions of these
>remaining cases are covered by the same rule, even though the rule
>is described as "recursive."  I think that the writer has something
>else in mind, and in particular, something *other* than binding,
>but the author remains vague on exactly what this means.
>
>Clearly, both Lundh and the documentation draw some distinction
>between "binding" and some other forms of "assignment" (which remain
>ill-defined throughout).  This distinction is what I was referring
>to when I said that "=" means different things in different contexts.

Consider this:

x = 1
globals()['x'] = 1
locals()[1] = 1

What's the difference between the three?  Although there's a lot of
machinery amenable to manipulation, with the corresponding potential for
breaking the standard model, fundamentally it all comes down to the
intention that *some* piece of code establishes a target on the left-hand
side and binds it to the object returned by the right-hand side.  IME,
except when going down to the very lowest-level details, Python is
easiest to understand when you treat all assignment statements as working
the same.  It helps to remember that names and namespaces are in many
ways syntactic sugar for dicts or lists.

(Obviously, the example with locals() doesn't do what it purports to do,
but it shows how function/method namespaces work under the covers.)

Slicing is the one real exception, but again I think that it's easier to
understand by wedging your mental model into conformance with the simple
target/binding metaphor.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From davea at ieee.org  Fri Jul 10 09:55:58 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 09:55:58 -0400
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <4A57486E.9070900@ieee.org>

jhinak sen wrote:
> hi,
> i am a beginner in python language,
>
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the mean
> and sum in some other file :
> ""
> *#! /usr/bin/env python
>
> import re
> import cPickle as p
> import math
> from numpy import *
>
> f0= open("temp9","r+").readlines()
> f2= open("out1","r+")
> add_1=[ ];
> for i in range(0, len(f0)):
>         f1=f0[i].split()
>         add= float(f1[1])+float(f1[2])
>     mean= float(add)/2
>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
> repr(mean).ljust(7)
>         add_1.append(add)
>     add_1.append(mean)
>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
> repr(mean).ljust(7))
> print "printing from file"
> for i in range(0, len(add_1),2):
>         print add_1[i],"        ", add_1[i+1]
>
> f0.close()
> f2.close()*
>
>
> ""
>
> and this programme is givving me this error :
>
> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""
>
> please help to to find the error.
> or suggest some simpler or better way
>
> note:
> 1)file "temp9" is already exist
> 2)this programme is giving me all my outputs, but at the end of the out
> ..its giving me that error.
>
>   
Others have pointed out the specific problem that gives you this error.  
But I'd like to point out a few other things to consider:

1) Don't mix tabs and spaces.  Best practice is to bind tab to (4) 
spaces in your editor, and never have a tab in a Python source file.
2) Think about your variable names.  As it stands, f0 is a list of 
lines, f1 is a list of "word" within a line, and f2 is a file.  No 
wonder you accidentally tried to close the list.  I'd suggest things like:
      infile = open(....)
      lines = infile.readlines()
      outfile = open(....)

      for line in lines:
             words = line.split(" ")     or  even   val1, val2 = 
lines.split(" ")

   Then of course the last two lines become
   infile.close()
   outfile.close()

3) Learn to use the for statement directly on a list, rather than using 
len() on the list to make an index, then using the index to find the value
4) On the open() calls, get your modes right.  Looks like you really want
   infile = open(infilename, "r")
   outfile = open(outfilename, "w")
5) Consider using tuples in your add_1 list, rather than separate 
elements.  That way, each element of the list would contain both sum and 
mean.
               add_1.append((add, mean))

       and the final print would become

    for item in add_1:
        print item[0],"        ", item[1]

6) Put anything over three lines into a function, instead of doing it at 
module scope.  That way, you'll be clearer about what things are local 
to this code, and what might be useful to other code in the same module.
In this case,  infilename, and outfilename might be arguments to that 
function.

There are lots of other refinements, but these are all within your 
reach, and would make the program much clearer.



From usernet at ilthio.net  Fri Jul 10 10:05:13 2009
From: usernet at ilthio.net (Tim Harig)
Date: Fri, 10 Jul 2009 14:05:13 GMT
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
Message-ID: <tUH5m.17111$iz2.3737@nlpi070.nbdc.sbc.com>

On 2009-07-10, garabik-news-2005-05 at kassiopeia.juls.savba.sk <garabik-news-2005-05 at kassiopeia.juls.savba.sk> wrote:
> Tim Harig <usernet at ilthio.net> wrote:
>> On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
>>> I would like to learn a way of changing the colour of a particular
>>> part of the output text. I've tried the following
>> On Unix operating systems this would be done through the curses interface:
>> http://docs.python.org/library/curses.html
> Or using ANSI colour codes:

Which will only work for ANSI terminals.


From t.lehmann at rtsgroup.net  Fri Jul 10 10:07:22 2009
From: t.lehmann at rtsgroup.net (Thomas Lehmann)
Date: Fri, 10 Jul 2009 07:07:22 -0700 (PDT)
Subject: Tkinter only: table widget with canvas...
Message-ID: <fc75d14e-41b8-4cc8-ba0b-b2e1a1c04f5e@v20g2000yqm.googlegroups.com>

My intention is to keep dependencies low that means using python and
tkinter
as base package is quite easy because it's available on nearly every
system.

There is good documentation on Tkinter but going into the depth I'm
missing
many details. As an example...

Using the Tkinter.Canvas class I should be able to create a nice
table.
The missing informations are:

a) Assume I would have some different widgets to add per row. How
    do I get the maximum row height?

b) Assume something like a label in one column. The length of all
texts
    in a column will differ. How do I choose the maxium column width?

c) Placing headers in a canvas does not look like a good idea because
    I don't want to scroll the headers. Am I right?
    c.1) How do I place a none scrollable header in a canvas?  or
    c.2) How do I place all headers outside the canvas correctly above
the relating column?

best regards
Thomas


From davea at ieee.org  Fri Jul 10 10:17:55 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 10:17:55 -0400
Subject: Query regarding set([])?
In-Reply-To: <3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
Message-ID: <4A574D93.30103@ieee.org>

vox wrote:
> On Jul 10, 2:04 pm, Peter Otten <__pete... at web.de> wrote:
>   
>> You are probably misinterpreting len(s3). s3 contains lines occuring in
>> "file1" but not in "file2". Duplicate lines are only counted once, and the
>> order doesn't matter.
>>
>> So there are 119 lines that occur at least once in "file2", but not in
>> "file1".
>>
>> If that is not what you want you have to tell us what exactly you are
>> looking for.
>>
>> Peter
>>     
>
> Hi,
> Thanks for the answer.
>
> I am looking for a script that compares file1 and file2, for each line
> in file1, check if line is present in file2. If the line from file1 is
> not present in file2, print that line/write it to file3, because I
> have to know what lines to add to file2.
>
> BR,
> Andy
>
>
>   
There's no more detail in that response.  To the level of detail you 
provide, the program works perfectly.  Just loop through the set and 
write the members to the file.

But you have some unspecified assumptions:
    1) order doesn't matter
    2) duplicates are impossible in the input file, or at least not 
meaningful.  So the correct output file could very well be smaller than 
either of the input files.

And a few others that might matter:
    3) the two files are both text files, with identical line endings 
matching your OS default
    4) the two files are ASCII, or at least 8 bit encoded, using the 
same encoding  (such as both UTF-8)
    5) the last line of each file DOES have a trailing newline sequence





From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 10:22:11 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 14:22:11 GMT
Subject: Implementing a cache
References: <87ab3cwu3u.fsf@vostro.rath.org>
Message-ID: <00732984$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 09:22:29 -0400, Nikolaus Rath wrote:

> Hello,
> 
> I want to implement a caching data structure in Python that allows me
> to:
> 
>  1. Quickly look up objects using a key 2. Keep track of the order in
>  which the objects are accessed (most
>     recently and least recently accessed one, not a complete history)
>  3. Quickly retrieve and remove the least recently accessed object.

Google for "python LRU cache".

Here are the first three hits:

http://code.activestate.com/recipes/498245/
http://code.activestate.com/recipes/252524/
http://www.algorithm.co.il/blogs/index.php/programming/python/small-python-challenge-no-2-lru-cache/




-- 
Steven


From chris at simplistix.co.uk  Fri Jul 10 10:26:00 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Fri, 10 Jul 2009 15:26:00 +0100
Subject: Where does setuptools live?
In-Reply-To: <59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<mailman.2759.1246954003.8015.python-list@python.org>
	<59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
Message-ID: <4A574F78.9000801@simplistix.co.uk>

Inky 788 wrote:
> Currently, distutils itself is being actively developed. More info
> about this here: http://tarekziade.wordpress.com/
> 
> My (albeit anonymous) advice is: use distutils. Manually download
> packages as-needed from PyPI and install manually using standard
> distutils.

No thanks. I'm a big fan of buildout. Making it possible for packages to 
specify their dependencies is a big win...

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From vox2000 at gmail.com  Fri Jul 10 10:28:04 2009
From: vox2000 at gmail.com (vox)
Date: Fri, 10 Jul 2009 07:28:04 -0700 (PDT)
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
	<mailman.2952.1247235487.8015.python-list@python.org>
Message-ID: <a8e2285e-f3f4-4d74-95c0-12d2d3156d04@y19g2000yqy.googlegroups.com>

On Jul 10, 4:17?pm, Dave Angel <da... at ieee.org> wrote:
> vox wrote:
> > On Jul 10, 2:04 pm, Peter Otten <__pete... at web.de> wrote:
>
> >> You are probably misinterpreting len(s3). s3 contains lines occuring in
> >> "file1" but not in "file2". Duplicate lines are only counted once, and the
> >> order doesn't matter.
>
> >> So there are 119 lines that occur at least once in "file2", but not in
> >> "file1".
>
> >> If that is not what you want you have to tell us what exactly you are
> >> looking for.
>
> >> Peter
>
> > Hi,
> > Thanks for the answer.
>
> > I am looking for a script that compares file1 and file2, for each line
> > in file1, check if line is present in file2. If the line from file1 is
> > not present in file2, print that line/write it to file3, because I
> > have to know what lines to add to file2.
>
> > BR,
> > Andy
>
> There's no more detail in that response. ?To the level of detail you
> provide, the program works perfectly. ?Just loop through the set and
> write the members to the file.
>
> But you have some unspecified assumptions:
> ? ? 1) order doesn't matter
> ? ? 2) duplicates are impossible in the input file, or at least not
> meaningful. ?So the correct output file could very well be smaller than
> either of the input files.
>
> And a few others that might matter:
> ? ? 3) the two files are both text files, with identical line endings
> matching your OS default
> ? ? 4) the two files are ASCII, or at least 8 bit encoded, using the
> same encoding ?(such as both UTF-8)
> ? ? 5) the last line of each file DOES have a trailing newline sequence

Thanks all for the input!
I have guess I have to think it through a couple times more. :)

BR,
Andy


From digitig at gmail.com  Fri Jul 10 10:38:54 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 10 Jul 2009 15:38:54 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h33k3d$2uu$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
Message-ID: <aee48b3c0907100738o3a4957eej64e0b229ac245d75@mail.gmail.com>

2009/7/9 kj <no.email at please.post>:

> Thanks for the encouragement.

[snip]

> into code. ?And by this I mean not only assumptions about the
> correctness of their code (the typical scope of assertions), but
> also, more broadly, assumptions about the data that they are dealing
> with (which often comes from external sources with abysmal quality
> control).

There we diverge. A lot. If "correctness of the code trumps everything
else" (in fact, if it matters at all) and the external data has
"abysmal quality control" then it *must* be checked for correctness
before it is used. If it is not, you have no idea whether your output
is correct or not. And assertions *will* *not* reliably provide that
checking (because they may not be executed). You *must* actively check
the data, using good old-fasioned "if" statements and so on, because
not to do so is to declare that you *don't* care about correctness.
You *know* the input is often wrong, but you're not bothering to check
it?

-- 
Tim Rowe


From __peter__ at web.de  Fri Jul 10 10:59:53 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 16:59:53 +0200
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
	<mailman.2952.1247235487.8015.python-list@python.org>
	<a8e2285e-f3f4-4d74-95c0-12d2d3156d04@y19g2000yqy.googlegroups.com>
Message-ID: <h37l12$prp$03$1@news.t-online.com>

vox wrote:

> On Jul 10, 4:17 pm, Dave Angel <da... at ieee.org> wrote:
>> vox wrote:
>> > On Jul 10, 2:04 pm, Peter Otten <__pete... at web.de> wrote:
>>
>> >> You are probably misinterpreting len(s3). s3 contains lines occuring
>> >> in "file1" but not in "file2". Duplicate lines are only counted once,
>> >> and the order doesn't matter.
>>
>> >> So there are 119 lines that occur at least once in "file2", but not in
>> >> "file1".
>>
>> >> If that is not what you want you have to tell us what exactly you are
>> >> looking for.
>>
>> >> Peter
>>
>> > Hi,
>> > Thanks for the answer.
>>
>> > I am looking for a script that compares file1 and file2, for each line
>> > in file1, check if line is present in file2. If the line from file1 is
>> > not present in file2, print that line/write it to file3, because I
>> > have to know what lines to add to file2.
>>
>> > BR,
>> > Andy
>>
>> There's no more detail in that response.  To the level of detail you
>> provide, the program works perfectly.  Just loop through the set and
>> write the members to the file.
>>
>> But you have some unspecified assumptions:
>> 1) order doesn't matter
>> 2) duplicates are impossible in the input file, or at least not
>> meaningful.  So the correct output file could very well be smaller than
>> either of the input files.
>>
>> And a few others that might matter:
>> 3) the two files are both text files, with identical line endings
>> matching your OS default
>> 4) the two files are ASCII, or at least 8 bit encoded, using the
>> same encoding  (such as both UTF-8)
>> 5) the last line of each file DOES have a trailing newline sequence
> 
> Thanks all for the input!
> I have guess I have to think it through a couple times more. :)

Indeed. Note that others thinking through related problems have come up with

http://docs.python.org/library/difflib.html

Peter



From mondi at cs.unibo.it  Fri Jul 10 11:16:14 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Fri, 10 Jul 2009 15:16:14 +0000
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <mailman.2929.1247192119.8015.python-list@python.org>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
Message-ID: <h37eat$qmm$1@lec.cs.unibo.it>

Roger Binns wrote:
> jacopo mondi wrote:
>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>> add support to an experimental socket family.
> 
> You may find it considerably easier to use ctypes since that will avoid
> the need for any patching.  You'll also be able to control how read and
> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
> os.fdopen to convert your raw file descriptor into a Python file object
> if appropriate.
> 
> If you do use ctypes then you'll only need to distribute pure Python
> source code.
> 
> Roger

Wait a minute, am I confused or ctypes seems to be unusless for my needs?
Ctypes wraps a system shared object (as libc is) and gives you the
possibility to access its functions. What have I to wrap? the
fuctionalities I need to use are those exposed by the kernel via
sys/socket.h haeder (socket, bind, connect etc.).
Maybe I could wrapp _socket.so (I think it's possible) but seems to be
unuseless because I need to modify, for example, the parameters that
_socket.so passes to the socket() function in order to create a socket
owned by the new socket family I'm actualy experimenting.
Hope it's clear what I'm trying to explain...

Thanks anyway, but ctypes doen't seem to fit my needs..

cheers
	jacopo


From aahz at pythoncraft.com  Fri Jul 10 11:19:48 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 08:19:48 -0700
Subject: PyGtk Depends on Numeric
References: <1ebe9314-9434-459a-bd3e-2b2386a35f1b@n11g2000yqb.googlegroups.com>
Message-ID: <h37m6k$p37$1@panix3.panix.com>

In article <1ebe9314-9434-459a-bd3e-2b2386a35f1b at n11g2000yqb.googlegroups.com>,
dieter  <vel.accel at gmail.com> wrote:
>
>Get with the times people and port to numpy. :P
>Don't you think its about time?

Are you trying to get something to happen or just posting a random
drive-by?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From francois.dot.grondin at bpr-cso.dot.com  Fri Jul 10 11:20:48 2009
From: francois.dot.grondin at bpr-cso.dot.com (François Grondin)
Date: Fri, 10 Jul 2009 15:20:48 GMT
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
	<h36ki102d7m@news5.newsguy.com>
Message-ID: <k%I5m.34251$Db2.2196@edtnps83>


"David Bernier" <david250 at videotron.ca> a ?crit dans le message de news: 
h36ki102d7m at news5.newsguy.com...
> Musatov wrote:
>> On Jul 9, 7:54 pm, David Bernier <david... at videotron.ca> wrote:
>>> Musatov wrote:
>>>> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
>>>> its adopted use in Pakistan.  The search engine has grown in
>>>> popularity 10,000 fold following its Beta test launch three months ago
>>>> in April, 2009. Supporters of the site claim it is better than rival
>>>> Google upon which platform it is based. Controversy arose after
>>>> MeAmI.org search code allowed users to search other users Google
>>>> results with no advertising. "It is truly an innovative thing we are
>>>> doing," said Founder and CEO, Martin Musatov. "Letting users search
>>>> the results of other Google users immediately results in a level of
>>>> accuracy and relevance above and beyond Google." Google changed their
>>>> API following the launch or MeAmI.org and explored the possibility of
>>>> blocking site access from MeAmI.org to Google search results but was
>>>> unable to do so. Critics of MeAmI.org say what it is doing is
>>>> tantamount to intellectual theft. When asked about this topper Musatov
>>>> exclaimed, "The Internet was made for people, not companies." An
>>>> analyst at Goldman Sachs says, requesting to remain anonymous,
>>>> "MeAmI.org has a strong presence in promoting itself as a vehicle for
>>>> global activism and to tell you the truth, this makes it much more
>>>> likely an acquisition target than potential intellectual property
>>>> violator." Google could not be reached for comment.
>>> Mr. Musatov,  do you know who originally wrote the
>>> article above?
>>>
>>> Thank you.
>>>
>>> David Bernier- Hide quoted text -
>>>
>>> - Show quoted text -
>>
>> Yes.
>
> Mr. Musatov, do you know the name of the person who
> originally wrote the article above?
>
> Thank you.
>
> David Bernier

Maybe Mr. Musatov should answer the following questions instead :
1. Did you write the article above?
2. If not, who did? And I don't want AP as the answer, but the name of the 
journalist.

David, don't take it bad, but he answered your question with an accurate 
answer (yes), You gave him the opportunity to avoid the real answer and he 
took it. Based on Musatov's strange behavior and logic, don't expect more 
from him. Ask anyone else the same question and you'd get a real answer.

BTW, my guess for question 2 would be the Masked Logician, Floetry, 
scriber77, or Professor X.

Francois 




From aahz at pythoncraft.com  Fri Jul 10 11:23:29 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 08:23:29 -0700
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
	<pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
	<mailman.2948.1247229186.8015.python-list@python.org>
Message-ID: <h37mdh$rfm$1@panix3.panix.com>

In article <mailman.2948.1247229186.8015.python-list at python.org>,
Jean-Michel Pichavant  <jeanmichel at sequans.com> wrote:
>
>You could also verify there are at least N different characters used in 
>the sentence:
>
>N = 5 # must contains at least 5 different characters
>record = []
>for c in s:
>    if c not in record:
>        record += [c]
>if len(record) >= N:
>    print "at least %s different characters" % N

Much simpler and *way* more efficient with a set:

if len(set(s)) < N:
    print "Must have at least %s different characters" % N
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From Scott.Daniels at Acm.Org  Fri Jul 10 11:28:29 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 08:28:29 -0700
Subject: tough-to-explain Python
In-Reply-To: <007318de$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>

Steven D'Aprano wrote:
> Even *soup stock* fits the same profile as what Hendrik claims is almost 
> unique to programming. On its own, soup stock is totally useless. But you 
> make it, now, so you can you feed it into something else later on.
> 
> Or instant coffee.

I think I'll avoid coming to your house for a cup of coffee. :-)

--Scott David Daniels
Scott.Daniels at Acm.Org


From magobin at gmail.com  Fri Jul 10 11:33:18 2009
From: magobin at gmail.com (Alex)
Date: Fri, 10 Jul 2009 08:33:18 -0700 (PDT)
Subject: problem with keys combination!
Message-ID: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>

Hi at all,
  I made a simple program that make a screenshot of Desktop and use it
as fullscreen background and then a ball erase image making illusion
that erase Desktop. The program working fine and I succesfully blocked
all keys but I have a problem with hotkey combination Ctrl-Alt-
Del...that bypass my FullScreen Application. Reading in google I
understood that if I want disable this keys I have to operate in more
low level. But I'm a newbe and I don't know how to make it(operate
with api is very hard 4 me).I tried several days to find a workaround
like replace one of that keys but doesn't work :-((
Plus..I can't install pyHook because there isn't a 2.6 version :-((
Can someone help me ??
thanks in advance
Alex

This is a piece of my code:
while True:
    pg.event.pump()
    keyinput = pg.key.get_pressed()
    # press ESC to exit
    if keyinput[pg.K_ESCAPE]
            raise SystemExit
    if  keyinput[pygame.K_LALT] and keyinput[pygame.K_LCTRL] and
keyinput[pygame.K_DELETE]:
         win32api.keybd_event(win32con.VK_ESCAPE,0)
         #shell = win32com.client.Dispatch("WScript.Shell")
        #shell.SendKeys("{ESC}")
    #ignore keyboard input
    def IgnoreKeyboardInterrupt():
        return signal.signal(signal.SIGINT,signal.SIG_IGN)


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 11:48:47 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 15:48:47 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>
Message-ID: <00733dd0$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 08:28:29 -0700, Scott David Daniels wrote:

> Steven D'Aprano wrote:
>> Even *soup stock* fits the same profile as what Hendrik claims is
>> almost unique to programming. On its own, soup stock is totally
>> useless. But you make it, now, so you can you feed it into something
>> else later on.
>> 
>> Or instant coffee.
> 
> I think I'll avoid coming to your house for a cup of coffee. :-)


I meant the instant coffee powder is prepared in advance. It's useless on 
it's own, but later on you feed it into boiling water, add sugar and 
milk, and it's slightly less useless.



-- 
Steven


From davea at ieee.org  Fri Jul 10 11:57:21 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 11:57:21 -0400
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100718p5e48506cg2d133842972d6328@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>	
	<4A57486E.9070900@ieee.org>
	<3d4ff96c0907100718p5e48506cg2d133842972d6328@mail.gmail.com>
Message-ID: <4A5764E1.7010102@ieee.org>

jhinak sen wrote:
> hey,
> thanx a lot :)
> i got ur points .. and it really helps..
>
> and please also tell me ...
> where i can get more basic and detail knowledge of python.. as i am
> beginners in this , i need more examples  of python programmes so that i can
> understand better.
> also if you know of any gud pdf file or book please let me know
>
> thnx a lot
> jhinak
>
> On Fri, Jul 10, 2009 at 7:25 PM, Dave Angel <davea at ieee.org> wrote:
>
>   
>> jhinak sen wrote:
>>
>>     
>>> hi,
>>> i am a beginner in python language,
>>>
>>> i am trying with this programme :
>>> to find the addition and mean from a data set in a file and writing the
>>> mean
>>> and sum in some other file :
>>> ""
>>> *#! /usr/bin/env python
>>>
>>> import re
>>> import cPickle as p
>>> import math
>>> from numpy import *
>>>
>>> f0= open("temp9","r+").readlines()
>>> f2= open("out1","r+")
>>> add_1=[ ];
>>> for i in range(0, len(f0)):
>>>        f1=f0[i].split()
>>>        add= float(f1[1])+float(f1[2])
>>>    mean= float(add)/2
>>>        print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
>>> repr(mean).ljust(7)
>>>        add_1.append(add)
>>>    add_1.append(mean)
>>>        f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
>>> repr(mean).ljust(7))
>>> print "printing from file"
>>> for i in range(0, len(add_1),2):
>>>        print add_1[i],"        ", add_1[i+1]
>>>
>>> f0.close()
>>> f2.close()*
>>>
>>>
>>> ""
>>>
>>> and this programme is givving me this error :
>>>
>>> ""    *Traceback (most recent call last):
>>>  File "./temporary1.py", line 24, in <module>
>>>    f0.close()
>>> AttributeError: 'list' object has no attribute 'close'*
>>> ""
>>>
>>> please help to to find the error.
>>> or suggest some simpler or better way
>>>
>>> note:
>>> 1)file "temp9" is already exist
>>> 2)this programme is giving me all my outputs, but at the end of the out
>>> ..its giving me that error.
>>>
>>>
>>>
>>>       
>> Others have pointed out the specific problem that gives you this error.
>>  But I'd like to point out a few other things to consider:
>>
>> 1) Don't mix tabs and spaces.  Best practice is to bind tab to (4) spaces
>> in your editor, and never have a tab in a Python source file.
>> 2) Think about your variable names.  As it stands, f0 is a list of lines,
>> f1 is a list of "word" within a line, and f2 is a file.  No wonder you
>> accidentally tried to close the list.  I'd suggest things like:
>>     infile = open(....)
>>     lines = infile.readlines()
>>     outfile = open(....)
>>
>>     for line in lines:
>>            words = line.split(" ")     or  even   val1, val2 =
>> lines.split(" ")
>>
>>  Then of course the last two lines become
>>  infile.close()
>>  outfile.close()
>>
>> 3) Learn to use the for statement directly on a list, rather than using
>> len() on the list to make an index, then using the index to find the value
>> 4) On the open() calls, get your modes right.  Looks like you really want
>>  infile = open(infilename, "r")
>>  outfile = open(outfilename, "w")
>> 5) Consider using tuples in your add_1 list, rather than separate elements.
>>  That way, each element of the list would contain both sum and mean.
>>              add_1.append((add, mean))
>>
>>      and the final print would become
>>
>>   for item in add_1:
>>       print item[0],"        ", item[1]
>>
>> 6) Put anything over three lines into a function, instead of doing it at
>> module scope.  That way, you'll be clearer about what things are local to
>> this code, and what might be useful to other code in the same module.
>> In this case,  infilename, and outfilename might be arguments to that
>> function.
>>
>> There are lots of other refinements, but these are all within your reach,
>> and would make the program much clearer.
>>
>>
>>     
>
>   
Please don' t top-post.  Putting your reply out of order makes it harder 
for others to see the sequences of things.  Some people top-post 
everything, but on this mailing list (and maybe most), the standard is 
to add to bottom, or inline where appropriate.

Anyway,
http://docs.python.org/tutorial/
http://diveintopython.org/
http://www.openbookproject.net/thinkCSpy/

are all good, depending on your experience with other languages, and 
with your computer's OS.

You could also check out
http://code.activestate.com/recipes/     or    
http://code.activestate.com/recipes/langs/python/  for Python specifically

which has a large set of relatively small modules of code.
For a examples that might stretch your thought process:
    http://code.activestate.com/recipes/576755/
    http://code.activestate.com/recipes/576647/




From darcy at druid.net  Fri Jul 10 12:09:28 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Fri, 10 Jul 2009 12:09:28 -0400
Subject: tough-to-explain Python
In-Reply-To: <00733dd0$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>
	<00733dd0$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <20090710120928.075451c8.darcy@druid.net>

On 10 Jul 2009 15:48:47 GMT
Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
> I meant the instant coffee powder is prepared in advance. It's useless on 
> it's own, but later on you feed it into boiling water, add sugar and 
> milk, and it's slightly less useless.

I don't know about that.  I find instant coffee pretty useless no
matter what it is fed to.  :-)

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From bryanvick at gmail.com  Fri Jul 10 12:13:41 2009
From: bryanvick at gmail.com (Bryan)
Date: Fri, 10 Jul 2009 09:13:41 -0700 (PDT)
Subject: Automate rsync w/ authentication
Message-ID: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>

I am trying to automate rsync to backup server A from server B.  I
have set up a private/public key between the two servers so I don't
have to enter a password when using rsync.  Running rsync manually
with the following command works fine:
rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp

But when I try to do it with python, the subprocess simply returns the
ssh -h output on stderr like I am passing some invalid syntax.  What
is wrong in my translation of rsync's -e command from shell to
pythyon?

#! /usr/bin/python
from subprocess import Popen, PIPE
rsyncExec = '/usr/bin/ssh'
source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
dest = '/home/bry/tmp'
rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
try:
	p = Popen(args, stdout=PIPE, stderr=PIPE)
	print 'rsync running with pid %s' % p.pid
	out, err = p.communicate()
	print 'Errors: %s' % err
	print 'Output: %s' % out
except Exception:
	print 'Error running rsync'



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 12:14:04 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 16:14:04 GMT
Subject: problem with keys combination!
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
Message-ID: <007343bd$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 08:33:18 -0700, Alex wrote:

> Hi at all,
>   I made a simple program that make a screenshot of Desktop and use it
> as fullscreen background and then a ball erase image making illusion
> that erase Desktop. The program working fine and I succesfully blocked
> all keys but I have a problem with hotkey combination Ctrl-Alt-
> Del...that bypass my FullScreen Application.


What operating system are you using? Windows?

As I understand it, you can't block, modify, or otherwise access Ctrl-Alt-
Del while running under Windows: it is the "Secure Attention Key", and is 
designed to be virtually impossible to interfere with. It's not *quite* 
impossible, but it is the deepest, darkest black magic. Microsoft makes 
it close enough to impossible as makes no difference even for experienced 
developers.

As a newbie, well, put it this way: it's like somebody saying "Hi guys, I 
have a shiny new Swiss Army Knife, the one with the screwdriver and the 
corkscrew. I'd like to build my own Space Shuttle -- what do I do?"

http://stackoverflow.com/questions/886076/how-can-i-intercept-all-key-events-including-ctrlaltdel-and-ctrltab

http://en.wikipedia.org/wiki/Control-Alt-Delete

You should also read this:

http://blogs.msdn.com/oldnewthing/archive/2004/02/16/73780.aspx



-- 
Steven


From mal at egenix.com  Fri Jul 10 12:15:31 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Fri, 10 Jul 2009 18:15:31 +0200
Subject: DBI module deprecated at Python 2.5--what to use in its place?
In-Reply-To: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
Message-ID: <4A576923.6050507@egenix.com>

dana wrote:
> I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
> modules together. Although I don't have Python 2.5, I've been informed
> the DBI module has been deprecated at 2.5. A few questions:
> 
> 1) Although deprecated, will it work at all in 2.5? Does the fact that
> it is deprecrated mean it has been removed entirely, or does Python
> 2.5 simply issuing a warning?
> 
> 2) What do I use in place of DBI for my Python 2.4. scripts that
> import modules DBI and ODBC together. I don't use DBI directly. It was
> simply a dependency for the ODBC module as best I knew.

If you're looking for a stable and maintained ODBC for Python,
have a look at our mxODBC extension or mxODBC Connect package:

http://www.egenix.com/products/python/mxODBC/
http://www.egenix.com/products/python/mxODBCConnect/

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 10 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 12:17:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 16:17:09 GMT
Subject: help me to find the error
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
	<4A57486E.9070900@ieee.org>
	<3d4ff96c0907100718p5e48506cg2d133842972d6328@mail.gmail.com>
	<mailman.2958.1247241458.8015.python-list@python.org>
Message-ID: <00734476$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 11:57:21 -0400, Dave Angel wrote:

[...]
> Please don' t top-post.  Putting your reply out of order makes it harder
> for others to see the sequences of things.  Some people top-post
> everything, but on this mailing list (and maybe most), the standard is
> to add to bottom, or inline where appropriate.

Inline is nearly always appropriate. Please trim your replies, leaving 
only what you need for context and what you are replying to directly, not 
the entire every-growing collection of quoted-quoted-quoted-quoted-quotes.

Thank you.


-- 
Steven


From mal at egenix.com  Fri Jul 10 12:18:28 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Fri, 10 Jul 2009 18:18:28 +0200
Subject: Remoting over SSH
In-Reply-To: <4A549B07.2090402@gmail.com>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
	<4A549B07.2090402@gmail.com>
Message-ID: <4A5769D4.8080106@egenix.com>

Lucas Carvalho wrote:
> Hussein B wrote:
>> Hey,
>> I want to perform commands on a remote server over SSH.
>> What do I need?
>> Thanks.
>>   
> Hi,
> If you want to use the SSH2 protocol into a python code, you should
> take a look at this module: paramiko [1].
> 
> [1] http://www.lag.net/paramiko/

If you're looking for remote Python execution over SSH have
a look at http://codespeak.net/py/dist/execnet.html

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 10 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From pdpinheiro at gmail.com  Fri Jul 10 12:23:55 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Fri, 10 Jul 2009 09:23:55 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org> 
	<007318de$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <c40ec96a-5494-483c-a461-676c8bb29876@x3g2000yqa.googlegroups.com>

On Jul 10, 2:11?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Fri, 10 Jul 2009 12:54:21 +0200, Hendrik van Rooyen wrote:
> > "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
>
> >>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>
> >>>> persistent idea "out there" that programming is a very accessible
> >>>> skill, like cooking or gardening, anyone can do it, and even profit
> >>>> from it, monetarily or otherwise, etc., and to some extent I am
>
> >>> Programming is not like any other human activity.
>
> >>In practice? In principle? Programming in principle is not the same as
> >>it is performed in practice.
>
> >>But in either case, programming requires both the logical reasoning of
> >>mathematics and the creativity of the arts. Funnily enough,
>
> > I do not buy this arty creativity stuff. - or are you talking about
> > making a website look pretty?
>
> I must admit, it never crossed my mind that anyone here would claim that
> there was no creativity involved in programming, that it was all a
> mindless, algorithmic process capable of being done by a simple
> mechanical device.
>
> This is certainly the accusation made against *bad* programmers -- that
> they can't actually solve new, unique problems, but just apply recipes
> they learned without any insight or intelligence. The sort of people who
> program so poorly that "a trained monkey could do what they do".

I wholeheartedly agree. Coming up with Duff's device is nothing if not
creative. My mind still reels at trying to grok it.
http://www.lysator.liu.se/c/duffs-device.html

> Even *soup stock* fits the same profile as what Hendrik claims is almost
> unique to programming. On its own, soup stock is totally useless. But you
> make it, now, so you can you feed it into something else later on.
>
> Or instant coffee.

I've always found cooking an apt metaphor for programming.

You've got your well-limited for loops (cook for x minutes), your less
straightforward while/until loops (roast until golden), you have your
subprocedures (prepare sauce in advance/in parallel), you have some
conditionals (tenderize the steak if the meat isn't really that
tender), etc etc.

The complexities of assignment can be easily visualized in terms of
containers and mixing stuff together. Nothing makes a += b more
obvious than having a bowl of cream (a), an egg (b), and adding the
egg to the bowl of cream (a += b). Well, except for the part where
that in that case evaluating b is destructive ;)

> They can't reason? Then what are they doing when they manipulate symbols?

"Computers aren't intelligent. They only think they are." Or, more to
the point: the typical definition of "reasoning" tends to involve more
of what defines humans as self-aware, animate beings than what is
usually ascribed to computers.


From charles at declareSub.com  Fri Jul 10 12:27:25 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Fri, 10 Jul 2009 12:27:25 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <DCF5052E-509C-47EF-B7BD-E942B739D6C7@declareSub.com>


On Jul 9, 2009, at 10:57 PM, Steven D'Aprano wrote:

> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
>
>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>>
>>> Nobody says you shouldn't check your data. Only that "assert" is not
>>> the right way to do that.
>>
>> "assert" is not the right way to check your *inputs*. It's a  
>> perfectly
>> reasonable way to check data which "should" be valid, as well as a  
>> way
>> to document what variables are supposed to contain.
>
> Where are those variables coming from?
>
> The distinction really boils down to this:
>
> * asserts should never fail. If there is any chance that an assertion
> might fail outside of test suites, then don't use assert.
>
>
> You can't control what input the caller provides to a function, so  
> unless
> the data is generated inside the function, a caller might provide
> something unexpected. Therefore, assert is inappropriate for checking
> function parameters, even if that function is "private" and only  
> called
> by your own functions.
>
> (1) So-called "private" or "internal" functions have a habit of  
> becoming
> public, and then you have asserts in public functions.
>
> (2) If public() calls _private(x), and _private uses assert to check  
> the
> value of x, there is a risk that if public() is buggy and supplies an
> invalid x, the assertion will never be checked and _private() will  
> return
> incorrect results.
>
> (3) assert is absolutely unsuitable for enforcing pre-conditions and  
> post-
> conditions, unless such conditions are mere "guidelines", because  
> assert
> can be switched off at runtime.


Unless, of course, you want to switch off such checking at runtime, as  
you might when using a design-by-contract approach.

Charles Yeomans


From aahz at pythoncraft.com  Fri Jul 10 12:33:06 2009
From: aahz at pythoncraft.com (Aahz)
Date: Fri, 10 Jul 2009 09:33:06 -0700
Subject: BayPIGgies at OSCON: 7/23 8-9:30pm
Message-ID: <20090710163306.GA10586@panix.com>

NOTE: time change AND location change

The July BayPIGgies meeting will be held at OSCON in the San Jose
Convention Center as one of the BoF (Birds of a Feather) sessions from
8pm to 9:30pm Thursday July 23.  Everyone is welcome: you do NOT need to
be an OSCON member to attend a BoF.

Wesley Chun will have a newbie-oriented "What is Python?" BoF from 7-8pm
in the same room as BayPIGgies (we don't know which room yet).

The July meeting is supposed to have a Django focus, but the program
hasn't been settled yet, either.

For more information, see
http://baypiggies.net/

Discussion of details will take place on the BayPIGgies list:
http://mail.python.org/mailman/listinfo/baypiggies
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From gabrielmonnerat at gmail.com  Fri Jul 10 12:36:22 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Fri, 10 Jul 2009 13:36:22 -0300
Subject: problem with subprocess
Message-ID: <4A576E06.5080006@gmail.com>

Hi all,

I need start a openoffice in Xvfb, but when I call with the DISPLAY 
occurs this error:

[root at localhost oood]# Xvfb :99 -screen 0 1024x768x24 &
 
In [9]: subprocess.call('/opt/ooo-dev3/program/soffice.bin')
Out[9]: 0

In [10]: subprocess.call('DISPLAY=:99 /opt/ooo-dev3/program/soffice.bin')
---------------------------------------------------------------------------
OSError                                   Traceback (most recent call last)

/home/gabriel/<ipython console> in <module>()

/usr/lib/python2.6/subprocess.pyc in call(*popenargs, **kwargs)
    442     retcode = call(["ls", "-l"])
    443     """
--> 444     return Popen(*popenargs, **kwargs).wait()
    445
    446

/usr/lib/python2.6/subprocess.pyc in __init__(self, args, bufsize, 
executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, 
env, universal_newlines, startupinfo, creationflags)
    593                             p2cread, p2cwrite,
    594                             c2pread, c2pwrite,
--> 595                             errread, errwrite)
    596
    597         # On Windows, you cannot just redirect one or two 
handles: You


/usr/lib/python2.6/subprocess.pyc in _execute_child(self, args, 
executable, preexec_fn, close_fds, cwd, env, universal_newlines, 
startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, 
errread, errwrite)
   1104                 os.waitpid(self.pid, 0)
   1105                 child_exception = pickle.loads(data)
-> 1106                 raise child_exception
   1107
   1108

OSError: [Errno 2] No such file or directory

I am using subprocess because I need store the pid. Any suggestions?

thanks in advance,

Gabriel M. Monnerat



From inky788 at gmail.com  Fri Jul 10 12:44:34 2009
From: inky788 at gmail.com (Inky 788)
Date: Fri, 10 Jul 2009 09:44:34 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com> 
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net> 
	<mailman.2759.1246954003.8015.python-list@python.org>
	<59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
	<mailman.2953.1247235967.8015.python-list@python.org>
Message-ID: <cb69063d-44a2-4706-9efc-90b3bda480f8@f33g2000vbm.googlegroups.com>

On Jul 10, 10:26?am, Chris Withers <ch... at simplistix.co.uk> wrote:
> Inky 788 wrote:
> > Currently, distutils itself is being actively developed. More info
> > about this here:http://tarekziade.wordpress.com/
>
> > My (albeit anonymous) advice is: use distutils. Manually download
> > packages as-needed from PyPI and install manually using standard
> > distutils.
>
> No thanks. I'm a big fan of buildout. Making it possible for packages to
> specify their dependencies is a big win...

Yup, it's a big win. But package installation for Python is a bit of a
mess right now. Neither setuptools nor buildout (nor pip for that
matter) are a standard part of Python. It's rather silly that although
Python is a batteries-included language, and it's mid-2009, and Python
3.1 has been released, that Python *still* doesn't have a standard
built-in way to handle package installation (including dependencies
and uninstallation).

My guess is that once distutils finishes getting spruced up, some
intrepid hacker is going to:

* take the best parts of pip and the best parts of setuptools (I don't
know anything about buildout),

* stir vigorously,

* ruthlessly remove the excess pieces,

* write good documentation for it,

* throw the result up on github/launchpad/bitbucket/whatever,

and then *that's* what everyone's going to start using and which will
eventually make it into the Python std lib.

But that's just my anon 2 cents.


From psimon at sonic.net  Fri Jul 10 12:47:42 2009
From: psimon at sonic.net (Paul Simon)
Date: Fri, 10 Jul 2009 09:47:42 -0700
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
	<h35f78$pts$1@ruby.cit.cornell.edu>
Message-ID: <4a5770bc$0$95549$742ec2ed@news.sonic.net>


"David Smith" <dns4 at cornell.edu> wrote in message 
news:h35f78$pts$1 at ruby.cit.cornell.edu...
> Paul Simon wrote:
>> "Peter Otten" <__peter__ at web.de> wrote in message
>> news:h3481q$d95$00$1 at news.t-online.com...
>>> Paul Simon wrote:
>>>
>>>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>>>> news:mailman.2863.1247095339.8015.python-list at python.org...
>>>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>>>> I have the "tkinter" problem and need some assistance to straighten it
>>>>> out.
>>>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as 
>>>>> >in
>>>>>> "step
>>>>> 1" and cannot import "_tkinter." I do not have that file on my 
>>>>> computer,
>>>>> but
>>>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>>>> This python stuff is great, but the documentation frequently
>>>>> feels like it is just a bit out of my grasp. I realize that all of 
>>>>> this
>>>>> is free but I understand the instructions on the web page to repair 
>>>>> only
>>>>> to the
>>>>> point of confusion. I'm not an expert. How do I modify my python
>>>>> configuration? Is there a file that needs to be edited? Which setup.py
>>>>> file
>>>>> do I use? Make? or python setup.py build and python setup.py install?
>>>>> Thanks. I appreciate your help.
>>>> - How did you install Python?
>>>> - What Linux distro are you using?
>>>>
>>>> Cheers,
>>>> Chris
>>>> http://blog.rebertia.com
>>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not 
>>>> sure
>>>> exactly how I installed Python.  Originally I had installed 2.5 from 
>>>> RPM
>>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>>> something from python.org and installed.  Not sure if it was tarball or
>>>> zip file.
>>> Zip or tar doesn't matter, you are installing "from source".
>>>
>>> Python has to find the necessary include files for tcl/tk. These are in
>>> separate packages that you have to install before you invoke Python's
>>> configure script.
>>>
>>> I don't know what they are called on your system -- look for tk-dev.rpm,
>>> tcl-dev.rpm or similar.
>>>
>>> You may run into the same problem with other modules like readline.
>>>
>>> Peter
>>>
>>
>> Thank you Peter.  I understand what you are saying but don't know how to 
>> do
>> it.  Although I installed from source, I followed a "cookbook" recipe.
>> Could you tell me what files to execute, where they might be, and file
>> arguments?  I'm just ignorant, not stupid. ;-).
>>
>> Paul
>>
>>
>
> Just install the tkinter package from the Mandriva Linux Control
> Center's Software Management system.  I just did it, doing a search for
> tkinter brought it right up.  All done.
>
> --David

Thanks to all for your patient help.  I have made some progress, but still 
no success.  I installed Active Tcl-8.5.7 and corrected the PATH 
accordingly.  However I still get a "missing" message on building Python. 
"Failed to find the necessary bits (!) to build these modules:

....
_tkinter (among others)
To find the necessary bits, look in setup.py in detect_modules() for teh 
module's name."

Not sure what bits are, euphemism?  but am about to wipe the disk and 
reinstall linux, etc.

Paul 




From gabrielmonnerat at gmail.com  Fri Jul 10 12:48:50 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Fri, 10 Jul 2009 13:48:50 -0300
Subject: problem with subprocess
In-Reply-To: <4A576E06.5080006@gmail.com>
References: <4A576E06.5080006@gmail.com>
Message-ID: <4A5770F2.7050308@gmail.com>

gabrielmonnerat wrote:
> Hi all,
>
> I need start a openoffice in Xvfb, but when I call with the DISPLAY 
> occurs this error:
>
> [root at localhost oood]# Xvfb :99 -screen 0 1024x768x24 &
>
> In [9]: subprocess.call('/opt/ooo-dev3/program/soffice.bin')
> Out[9]: 0
>
> In [10]: subprocess.call('DISPLAY=:99 /opt/ooo-dev3/program/soffice.bin')
> --------------------------------------------------------------------------- 
>
> OSError                                   Traceback (most recent call 
> last)
>
> /home/gabriel/<ipython console> in <module>()
>
> /usr/lib/python2.6/subprocess.pyc in call(*popenargs, **kwargs)
>    442     retcode = call(["ls", "-l"])
>    443     """
> --> 444     return Popen(*popenargs, **kwargs).wait()
>    445
>    446
>
> /usr/lib/python2.6/subprocess.pyc in __init__(self, args, bufsize, 
> executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, 
> env, universal_newlines, startupinfo, creationflags)
>    593                             p2cread, p2cwrite,
>    594                             c2pread, c2pwrite,
> --> 595                             errread, errwrite)
>    596
>    597         # On Windows, you cannot just redirect one or two 
> handles: You
>
>
> /usr/lib/python2.6/subprocess.pyc in _execute_child(self, args, 
> executable, preexec_fn, close_fds, cwd, env, universal_newlines, 
> startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, 
> c2pwrite, errread, errwrite)
>   1104                 os.waitpid(self.pid, 0)
>   1105                 child_exception = pickle.loads(data)
> -> 1106                 raise child_exception
>   1107
>   1108
>
> OSError: [Errno 2] No such file or directory
>
> I am using subprocess because I need store the pid. Any suggestions?
Sorry, I was forgot the parameter shell=True.
i.e
In [20]: subprocess.call('DISPLAY=:99 
/opt/ooo-dev3/program/soffice.bin',shell=True)

lack of attention mine
>
> thanks in advance,
>
> Gabriel M. Monnerat
>
>
Gabriel M. Monnerat


From jcd at sdf.lonestar.org  Fri Jul 10 12:50:27 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 12:50:27 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <1247244628.8029.15.camel@aalcdl07>

On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
> 
> > On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
> > 
> >> Nobody says you shouldn't check your data. Only that "assert" is not
> >> the right way to do that.
> > 
> > "assert" is not the right way to check your *inputs*. It's a perfectly
> > reasonable way to check data which "should" be valid, as well as a way
> > to document what variables are supposed to contain.
> 
> Where are those variables coming from?
> 
> The distinction really boils down to this:
> 
> * asserts should never fail. If there is any chance that an assertion 
> might fail outside of test suites, then don't use assert.
> 

I'm no expert, but the more I read this thread, and the more I think on
it, the more I believe that asserts don't really need to exist outside
of test suites.  The function that assertions provide is handled in a
far more robust and maintainable way by unit tests and doctests.
Anything else should be handled by more descriptive exceptions.  

The use of assertions in regular code may just be a historical baby step
on the way to real code testing.

To play devils advocate for a moment, one possible use case for assert
statements is if you need to test something that you can't easily get
under a proper unittest or doctest.  Maybe you need to know the value of
a variable halfway through a method.  A judicious assertion can help
supplement your test suite  A better solution would be to refactor so
you can get the needed value under test, but if time constraints won't
allow it, then make your assertion and move on, but only to help you
debug the code, not to protect your code at runtime.  Even then, why not
use a proper Exception (unless speed is a major issue)?

Even if it is only used internally in a module, I would still prefer a
ValueError to an AssertionError.  It tells you what's happening more
clearly.  And it protects you if another caller (even one internal to
the class) calls it with a different set of assumptions.

At minimum, I think there's a heavy burden on an author to justify the
use of AssertionErrors rather than other kinds of Exceptions. 

Cheers,
Cliff



From magobin at gmail.com  Fri Jul 10 12:52:47 2009
From: magobin at gmail.com (Alex)
Date: Fri, 10 Jul 2009 09:52:47 -0700 (PDT)
Subject: problem with keys combination!
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
	<007343bd$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <03eeae5c-fe58-41d1-91ea-f3e5dba602dc@h11g2000yqb.googlegroups.com>

Hi Steven,

> As I understand it, you can't block, modify, or otherwise access Ctrl-Alt-
> Del while running under Windows: it is the "Secure Attention Key", and is
> designed to be virtually impossible to interfere with. It's not *quite*
> impossible, but it is the deepest, darkest black magic. Microsoft makes
> it close enough to impossible as makes no difference even for experienced
> developers.

No, is possible but for my level is quite impossible:

http://www.codeproject.com/KB/winsdk/AntonioWinLock.aspx

...in this article the author move a lot a functions in a dll  and
make a demonstration with a VB and C code to use it...plus...there is
his program that make it :-))))
I thought that python can read dll via ctypes...but it's very hard for
me :-((

>
> As a newbie, well, put it this way: it's like somebody saying "Hi guys, I
> have a shiny new Swiss Army Knife, the one with the screwdriver and the
> corkscrew. I'd like to build my own Space Shuttle -- what do I do?"
>
:-))))))))))....but yes We caaaaannnnnnn

Alex


From robert.kern at gmail.com  Fri Jul 10 12:57:16 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 10 Jul 2009 11:57:16 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <1247244628.8029.15.camel@aalcdl07>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>	<pan.2009.07.10.02.28.04.344000@nowhere.com>	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<1247244628.8029.15.camel@aalcdl07>
Message-ID: <h37rtd$etd$1@ger.gmane.org>

On 2009-07-10 11:50, J. Cliff Dyer wrote:
> On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
>> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
>>
>>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>>>
>>>> Nobody says you shouldn't check your data. Only that "assert" is not
>>>> the right way to do that.
>>> "assert" is not the right way to check your *inputs*. It's a perfectly
>>> reasonable way to check data which "should" be valid, as well as a way
>>> to document what variables are supposed to contain.
>> Where are those variables coming from?
>>
>> The distinction really boils down to this:
>>
>> * asserts should never fail. If there is any chance that an assertion
>> might fail outside of test suites, then don't use assert.
>>
>
> I'm no expert, but the more I read this thread, and the more I think on
> it, the more I believe that asserts don't really need to exist outside
> of test suites.

Actually, there is a good argument that one shouldn't use an assert statement in 
test suites: code can have bugs that only show up under -O so you want to be 
able to run your test suite under -O.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From inky788 at gmail.com  Fri Jul 10 12:57:46 2009
From: inky788 at gmail.com (Inky 788)
Date: Fri, 10 Jul 2009 09:57:46 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com> 
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net> 
	<mailman.2759.1246954003.8015.python-list@python.org>
	<59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
	<mailman.2953.1247235967.8015.python-list@python.org>
Message-ID: <d29a71b6-6b3c-4b42-a054-4327dbd7552a@g23g2000vbr.googlegroups.com>

On Jul 10, 10:26?am, Chris Withers <ch... at simplistix.co.uk> wrote:
> Inky 788 wrote:
> > Currently, distutils itself is being actively developed. More info
> > about this here:http://tarekziade.wordpress.com/
>
> > My (albeit anonymous) advice is: use distutils. Manually download
> > packages as-needed from PyPI and install manually using standard
> > distutils.
>
> No thanks. I'm a big fan of buildout. Making it possible for packages to
> specify their dependencies is a big win...

Read this: http://tarekziade.wordpress.com/2009/07/03/dropping-pep-386-versions-comparison/

So, again, I don't know anything about buildout, and it might be a
nice interim solution, but there are some new and exciting
developments in distutils coming down the pike, and whatever becomes
the standard Python package management system will very likely be
based on those new developments.

I just hope it all happens sooner than later. :)


From manuel.graune at koeln.de  Fri Jul 10 13:00:11 2009
From: manuel.graune at koeln.de (Manuel Graune)
Date: Fri, 10 Jul 2009 19:00:11 +0200
Subject: Nested Classes and Instances
Message-ID: <m3r5woh3s4.fsf@uriel.graune.org>


Hello,

as an example of what I would like to achieve, think of a street
where each house has a door and a sign with a unique (per house)
number on it. I tried to model this like this:

class House(object):
    class Door(object):
        def __init__(self,color):
             self.color=color
    class Sign(object):
        def __init__(self,text):
             self.text=text
    def __init__(self, doorcolor,housenumber):
        self.housenumber=housenumber
        self.door=House.Door(doorcolor)
        self.sign=House.Sign(housenumber)

house1=House("red","1")
house2=House("blue","2")

Well, so far, so good. Now, what I'd like to achive is that the text of
the "sign" changes whenever the variable "housenumber" of the
"parent-instance" changes or  that
"house1.sign.text" is a reference/pointer to "house1.housenumber"

Thanks in advance,

Manuel



-- 
A hundred men did the rational thing. The sum of those rational choices was
called panic. Neal Stephenson -- System of the world
http://www.graune.org/GnuPG_pubkey.asc
Key fingerprint = 1E44 9CBD DEE4 9E07 5E0A  5828 5476 7E92 2DB4 3C99


From lists at cheimes.de  Fri Jul 10 13:21:43 2009
From: lists at cheimes.de (Christian Heimes)
Date: Fri, 10 Jul 2009 19:21:43 +0200
Subject: problem with subprocess
In-Reply-To: <4A5770F2.7050308@gmail.com>
References: <4A576E06.5080006@gmail.com> <4A5770F2.7050308@gmail.com>
Message-ID: <h37tb7$j33$1@ger.gmane.org>

gabrielmonnerat wrote:
>> I am using subprocess because I need store the pid. Any suggestions?
> Sorry, I was forgot the parameter shell=True.
> i.e
> In [20]: subprocess.call('DISPLAY=:99
> /opt/ooo-dev3/program/soffice.bin',shell=True)

You should avoid using the shell=True parameter. It may result in
security issues and it consumes more resources. Try this:

env = os.environ.copy()
env["DISPLAY"] = ":99"
subprocess.call(['opt/ooo-dev3/program/soffice.bin', env=env)

Christian



From thudfoo at opensuse.us  Fri Jul 10 13:24:22 2009
From: thudfoo at opensuse.us (member thudfoo)
Date: Fri, 10 Jul 2009 10:24:22 -0700
Subject: can i write a assemly language programs in python
In-Reply-To: <4A573627.8090308@tim.thechases.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
	<4A573627.8090308@tim.thechases.com>
Message-ID: <3d881a310907101024o7c03448cyc45103d54e7cc4ef@mail.gmail.com>

On Fri, Jul 10, 2009 at 5:37 AM, Tim Chase<python.list at tim.thechases.com> wrote:
> m.reddy prasad reddy wrote:
>>
>> can any one tell me how to write assembly language programs in python...if
>> no is there any other way to write the programs in python
>
> Bah, writing assembly language is easy in Python:
>
> ?print("MOV EAX, [EBX]")
> ?print("XOR EBX, EBX")
>
> Just adjust the strings for your favorite processor architecture and Python
> will produce the assembly code you want.
>
> Now compiling assembly to *machine* code...or calling between Python and
> assembly...that's another matter. ?But writing assembly language programs in
> Python? ?Easy. ;-)
>

"PyASM is a full-featured dynamic assembler written entirely in
Python. By dynamic, I mean that it can be used to generate and execute
machine code in python at runtime without requiring the generation of
object files and linkage. It essentially allow 'inline' assembly in
python modules on x86 platforms.

"PyASM can also generate object files (for windows) like a traditional
standalone assembler, although you're probably better off using one of
the many freely available assemblers if this is you primary goal."

http://members.verizon.net/~olsongt/usersGuide.html


From nleioatt at gmail.com  Fri Jul 10 13:26:07 2009
From: nleioatt at gmail.com (Nick)
Date: Fri, 10 Jul 2009 10:26:07 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<7xab3d9ykx.fsf@ruckus.brouhaha.com>
Message-ID: <04f36636-bf25-423e-8deb-d28d81511678@f16g2000vbf.googlegroups.com>

On Jul 9, 8:22 pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Nick <nleio... at gmail.com> writes:
> > text = file.readlines()
> > len = len(text)
> > fields = text[1].split()
>
> Is that intended to split the first line of the file?  Remember
> that arrays in python begin at index 0.

no the '1st line' is garbled meta data, but thanks man


From __peter__ at web.de  Fri Jul 10 13:37:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 19:37:15 +0200
Subject: Nested Classes and Instances
References: <m3r5woh3s4.fsf@uriel.graune.org>
Message-ID: <h37u84$sbr$01$1@news.t-online.com>

Manuel Graune wrote:

> as an example of what I would like to achieve, think of a street
> where each house has a door and a sign with a unique (per house)
> number on it. I tried to model this like this:
> 
> class House(object):
>     class Door(object):
>         def __init__(self,color):
>              self.color=color
>     class Sign(object):
>         def __init__(self,text):
>              self.text=text
>     def __init__(self, doorcolor,housenumber):
>         self.housenumber=housenumber
>         self.door=House.Door(doorcolor)
>         self.sign=House.Sign(housenumber)
> 
> house1=House("red","1")
> house2=House("blue","2")
> 
> Well, so far, so good. Now, what I'd like to achive is that the text of
> the "sign" changes whenever the variable "housenumber" of the
> "parent-instance" changes or  that
> "house1.sign.text" is a reference/pointer to "house1.housenumber"

Python doesn't support C-style pointers, but you can work around it to some 
degree:

>>> class House(object):
...     def __init__(self, housenumber):
...             self.housenumber = housenumber
...             self.sign = Sign(self)
...
>>> class Sign(object):
...     def __init__(self, house):
...             self.house = house
...     @property
...     def text(self): return self.house.housenumber
...
>>> house = House(42)
>>> house.sign.text
42
>>> house.housenumber = "42b"
>>> house.sign.text
'42b'

If you are concerned about the tight coupling between House and Sign you can 
modify Sign to accept a function that gets the housenumber:

>>> class House(object):
...     def __init__(self, n): self.housenumber = n
...
>>> class Sign(object):
...     def __init__(self, gettext):
...             self._gettext = gettext
...     @property
...     def text(self): return self._gettext()
...
>>> house = House(7)
>>> house.sign = Sign(lambda house=house: house.housenumber)
>>> house.sign.text
7

Peter



From h at realh.co.uk  Fri Jul 10 13:43:54 2009
From: h at realh.co.uk (Tony Houghton)
Date: Fri, 10 Jul 2009 18:43:54 +0100
Subject: Running a script to build docs from setup.py
References: <20090709173343.1784710d@realh.co.uk>
	<87fxd5ny79.fsf@benfinney.id.au>
Message-ID: <20090710184354.406c26ae@realh.co.uk>

On Fri, 10 Jul 2009 11:06:34 +1000
Ben Finney <ben+python at benfinney.id.au> wrote:

> Tony Houghton <h at realh.co.uk> writes:
> 
> > I've looked through the manual but I can't find any hooks in distutils
> > for generating files at install time other than extension modules and
> > .pyc files. Should I just run the script from somewhere in my setup.py
> > before calling distutils' setup function?
> 
> Indirectly related: Ian Bicking's article on using Python's ?setup.py?
> as a ?Makefile? replacement:
> 
>     <URL:http://blog.ianbicking.org/pythons-makefile.html>

Thanks, but I don't think that adds much to the distutils manual.

> If one is writing a ?setup.py? anyway, I think it makes sense to use
> that as the build program for the whole project if possible. Good
> hunting!

Yes. Really I only want to write a setup.py because it makes it easier
to make a debian package, but the more of the installation that's done
by setup.py the better I suppose, then other people might find it
useful.

-- 
TH * http://www.realh.co.uk



From wescpy at gmail.com  Fri Jul 10 13:48:43 2009
From: wescpy at gmail.com (Wesley Chun)
Date: Fri, 10 Jul 2009 10:48:43 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <89727cd5-a039-4295-8641-c5fe60e8b50f@m18g2000vbi.googlegroups.com>

On Jul 7, 1:04?pm, kj <no.em... at please.post> wrote:
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>     :
> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?
>     :
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!


kj,

i don't have too much to add to everyone else's response except to
describe how i deal with this. i teach Python courses several times a
year and realized long ago that conveying the concept of mutable vs.
immutable is a key to getting up-to-speed quickly with Python as well
as helping beginners.

so, although techically, this is more of an intermediate topic rather
than "beginner" material, i still teach it anyway, with the hopes of
producing better Python programmers out of the gate, and hopefully,
less frustrated ones. in fact, i dedicated an entire chapter (4) in
Core Python Programming just to address this important issue. to top
it all off, i end this module in the class by giving 2 quizzes, just
to make sure they understood what i just told them. i put the 1st one
online, so if you're curious, the PDF is at http://roadkill.com/~wesc/cyberweb/introQuiz.pdf
... the 2nd quiz is harder and involves the discussion of the
differences between shallow and deep copies. so yes, not very beginner-
ish stuff, hence the reason why i (re)named my course "Intro
+Intermediate Python".

finally, rather than the "paper tag" or alex's hotel statue analogy, i
just say that variables are like Post-It&reg; or sticky notes on
objects. i can tag objects anytime, tag objects more than once, remove
tags, or switch them to another object, etc.

just my $0.02,
-- wesley
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
"Core Python Programming", Prentice Hall, (c)2007,2001
"Python Fundamentals", Prentice Hall, (c)2009
    http://corepython.com

wesley.j.chun :: wescpy-at-gmail.com
python training and technical consulting
cyberweb.consulting : silicon valley, ca
http://cyberwebconsulting.com


From tony.lay at lmco.com  Fri Jul 10 14:03:05 2009
From: tony.lay at lmco.com (Lay, Tony)
Date: Fri, 10 Jul 2009 14:03:05 -0400
Subject: python make dies :libtk8.5.so: cannot open shared object file: No
	such file or directory
Message-ID: <71417B877DBC6946AFC52F0C1576C7D6474D7B524B@HVXMSP1.us.lmco.com>

Trying to build python-2.6.2

 

./configure --prefix=/usr/local --exec-prefix=/usr/local
LDFLAGS="-L/usr/local"

(runs through happily, had to make some libs local)

 

make runs most of the way until.

 

building '_tkinter' extension

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall
-Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I.
-I/tmp/meld/Python-2.6.2/./Include -I. -IInclude -I./Include
-I/usr/local/include -I/tmp/meld/Python-2.6.2/Include
-I/tmp/meld/Python-2.6.2 -c /tmp/meld/Python-2.6.2/Modules/_tkinter.c -o
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/_tkinter.o

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall
-Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I.
-I/tmp/meld/Python-2.6.2/./Include -I. -IInclude -I./Include
-I/usr/local/include -I/tmp/meld/Python-2.6.2/Include
-I/tmp/meld/Python-2.6.2 -c /tmp/meld/Python-2.6.2/Modules/tkappinit.c -o
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/tkappinit.o

gcc -pthread -shared
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/_tkinter.o
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/tkappinit.o
-L/usr/X11R6/lib64 -L/usr/X11R6/lib -L/usr/local/lib -ltk8.5 -ltcl8.5 -lX11
-o build/lib.linux-i686-2.6/_tkinter.so

*** WARNING: renaming "_tkinter" since importing it failed: libtk8.5.so:
cannot open shared object file: No such file or directory

 

Failed to find the necessary bits to build these modules:

_sqlite3           bsddb185           sunaudiodev

To find the necessary bits, look in setup.py in detect_modules() for the
module's name.

 

 

Failed to build these modules:

_tkinter

 

running build_scripts

# cd /usr/local/lib

# ls -la | grep libtk8.5.so

-r-xr-xr-x   1 root root  1112606 Jul 10 13:28 libtk8.5.so

Am I missing something, it's there?

 

Regards,

 

Tony Lay

UNIX Administration 

407-306-6559

Lockheed Martin - EBS 

One Company, One Team

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/14cdbeb5/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Anthony (Tony) Lay (tony.lay at lmco.com).vcf
Type: text/x-vcard
Size: 430 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/14cdbeb5/attachment.vcf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 7647 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/14cdbeb5/attachment.bin>

From digitig at gmail.com  Fri Jul 10 14:29:26 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 10 Jul 2009 19:29:26 +0100
Subject: language analysis to enforce code standards
In-Reply-To: <h37dac$cfk$00$1@news.t-online.com>
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
	<h37dac$cfk$00$1@news.t-online.com>
Message-ID: <aee48b3c0907101129o7b47822agdc2f5ea6961c0e72@mail.gmail.com>

2009/7/10 Peter Otten <__peter__ at web.de>:

> Don't be a fool. Have someone other than the author read the comment.

That's the winning answer as far as I'm concerned. Automated tools are
good for picking up some types of accidental mistakes, but for
checking that comments are meaningful (and variable names, for that
matter) you can't do without peer review.

Think about it. What's the purpose of "enforcing standards". Just a
tick in some assurance box to say "we meet these standards"? Ot to
ensure something about the product quality?

No automated tool -- not for a while yet, anyway -- is going to pick
up comments such as:

# increment x
x += 1

or

# You are not expected to understand this.

The former is the sort of thing that any programmer might produce when
against a deadline and forced to comment their code. The latter is a
classic from a programming guru of old. An automatic checker that just
checks that the comment exists without understanding its contents
simply is not adding value but is rather petty bureaucracy that will
annoy the programmers.


-- 
Tim Rowe


From clp2 at rebertia.com  Fri Jul 10 14:53:39 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 11:53:39 -0700
Subject: Automate rsync w/ authentication
In-Reply-To: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
Message-ID: <50697b2c0907101153k69a6b5ej88fbd3a9993ed5d2@mail.gmail.com>

On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
> I am trying to automate rsync to backup server A from server B. ?I
> have set up a private/public key between the two servers so I don't
> have to enter a password when using rsync. ?Running rsync manually
> with the following command works fine:
> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>
> But when I try to do it with python, the subprocess simply returns the
> ssh -h output on stderr like I am passing some invalid syntax. ?What
> is wrong in my translation of rsync's -e command from shell to
> pythyon?
>
> #! /usr/bin/python
> from subprocess import Popen, PIPE
> rsyncExec = '/usr/bin/ssh'
> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
> dest = '/home/bry/tmp'
> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

Like many problems involving the subprocess module, I think you've
tokenized the arguments incorrectly. Try:

rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]

Note that the -e switch and its operand are separate arguments for the
purposes of POSIX shell tokenization.

Cheers,
Chris
-- 
http://blog.rebertia.com


From edreamleo at charter.net  Fri Jul 10 14:54:50 2009
From: edreamleo at charter.net (Edward K Ream)
Date: Fri, 10 Jul 2009 13:54:50 -0500
Subject: ANN: Leo 4.6 rc1 released
Message-ID: <D8M5m.54324$c82.37596@newsfe08.iad>

Leo 4.6 rc1 is now available at:
http://sourceforge.net/project/showfiles.php?group_id=3458&package_id=29106

Leo is a text editor, data organizer, project manager and much more. See:
http://webpages.charter.net/edreamleo/intro.html

The highlights of Leo 4.6:
--------------------------

- Cached external files *greatly* reduces the time to load .leo files.
- Leo now features a modern Qt interface by default.
  Leo's legacy Tk interface can also be used.
- New --config, --file and --gui command-line options.
- Leo tests syntax of .py files when saving them.
- Leo can now open any kind of file into @edit nodes.
- @auto-rst nodes allow easy editing of reStructuredText files.
- Properties of commanders, positions and nodes simplify programming.
- Improved Leo's unit testing framework.
- Leo now requires Python 2.5 or later.
- Dozens of small improvements and bug fixes.

Links:
------
Leo:      http://webpages.charter.net/edreamleo/front.html
Forum:    http://groups.google.com/group/leo-editor
Download: http://sourceforge.net/project/showfiles.php?group_id=3458
Bzr:      http://code.launchpad.net/leo-editor/
Quotes:   http://webpages.charter.net/edreamleo/testimonials.html
--------------------------------------------------------------------
Edward K. Ream   email:  edreamleo at yahoo.com
Leo: http://webpages.charter.net/edreamleo/front.html
--------------------------------------------------------------------




From jcd at sdf.lonestar.org  Fri Jul 10 14:56:48 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 14:56:48 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h37rtd$etd$1@ger.gmane.org>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<1247244628.8029.15.camel@aalcdl07>  <h37rtd$etd$1@ger.gmane.org>
Message-ID: <1247252208.11457.6.camel@aalcdl07>

On Fri, 2009-07-10 at 11:57 -0500, Robert Kern wrote:
> On 2009-07-10 11:50, J. Cliff Dyer wrote:
> > On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
> >> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
> >>
> >>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
> >>>
> >>>> Nobody says you shouldn't check your data. Only that "assert" is not
> >>>> the right way to do that.
> >>> "assert" is not the right way to check your *inputs*. It's a perfectly
> >>> reasonable way to check data which "should" be valid, as well as a way
> >>> to document what variables are supposed to contain.
> >> Where are those variables coming from?
> >>
> >> The distinction really boils down to this:
> >>
> >> * asserts should never fail. If there is any chance that an assertion
> >> might fail outside of test suites, then don't use assert.
> >>
> >
> > I'm no expert, but the more I read this thread, and the more I think on
> > it, the more I believe that asserts don't really need to exist outside
> > of test suites.
> 
> Actually, there is a good argument that one shouldn't use an assert statement in 
> test suites: code can have bugs that only show up under -O so you want to be 
> able to run your test suite under -O.
> 

That's an interesting point.  Presumably TestCase.assert_() doesn't
suffer from this defect?  Otherwise the entire unittest suite is
essentially broken by your argument.  I suppose I should have said one
should only raise AssertionErrors in test suites.  Practically speaking,
that's what a test suite is:  The place where you assert what the code
does.





From jcd at sdf.lonestar.org  Fri Jul 10 14:59:29 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 14:59:29 -0400
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <3A693537-927D-44B1-840A-D97FACFB6809@pyth.net>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<3A693537-927D-44B1-840A-D97FACFB6809@pyth.net>
Message-ID: <1247252369.11457.8.camel@aalcdl07>

On Thu, 2009-07-09 at 13:53 +0000, Fri?rik M?r J?nsson wrote:
> Look at:
> 
>    len = len(text)
> 
> You're overriding `len` (a built-in method), with an integer  
> (`len(text)`).  You then call:
> 
>    for i in range(len(fields)):
> 
> But `len` is no longer a callable, but merely an integer.
> 
> Regards,
> Fri?rik M?r
> 
> P.S. While this is a fairly obvious problem it's usually a good idea  
> to post working code and a traceback when requesting help.

While we're on the subject of good question posting form:  The body of
your post should contain all relevant information.  Please don't make
readers look back at the subject heading for the statement of the
problem.  Duplicating the statement of the problem in the subject and
the body is ok, but it really ought to be in the body.



From Scott.Daniels at Acm.Org  Fri Jul 10 14:59:50 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 11:59:50 -0700
Subject: tough-to-explain Python
In-Reply-To: <00733dd0$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2944.1247223458.8015.python-list@python.org>	<007318de$0$9710$c3e8da3@news.astraweb.com>	<jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>
	<00733dd0$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <4-CdnSJso5pwEMrXnZ2dnUVZ_sVi4p2d@pdx.net>

Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 08:28:29 -0700, Scott David Daniels wrote:
>> Steven D'Aprano wrote:
>>> Even *soup stock* fits the same profile as what Hendrik claims is
>>> almost unique to programming. On its own, soup stock is totally
>>> useless. But you make it, now, so you can you feed it into something
>>> else later on.
>>> Or instant coffee.
>> I think I'll avoid coming to your house for a cup of coffee. :-)
> I meant the instant coffee powder is prepared in advance. It's useless on 
> it's own, but later on you feed it into boiling water, add sugar and 
> milk, and it's slightly less useless.

I know, but the image of even a _great_ soup stock with instant
coffee poured in, both appalled me and made me giggle.  So, I
thought I'd share.

--Scott David Daniels
Scott.Daniels at Acm.Org


From robert.kern at gmail.com  Fri Jul 10 15:02:58 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 10 Jul 2009 14:02:58 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <1247252208.11457.6.camel@aalcdl07>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>	<pan.2009.07.10.02.28.04.344000@nowhere.com>	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>	<1247244628.8029.15.camel@aalcdl07>
	<h37rtd$etd$1@ger.gmane.org> <1247252208.11457.6.camel@aalcdl07>
Message-ID: <h38392$5k4$1@ger.gmane.org>

On 2009-07-10 13:56, J. Cliff Dyer wrote:
> On Fri, 2009-07-10 at 11:57 -0500, Robert Kern wrote:
>> On 2009-07-10 11:50, J. Cliff Dyer wrote:
>>> On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
>>>> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
>>>>
>>>>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>>>>>
>>>>>> Nobody says you shouldn't check your data. Only that "assert" is not
>>>>>> the right way to do that.
>>>>> "assert" is not the right way to check your *inputs*. It's a perfectly
>>>>> reasonable way to check data which "should" be valid, as well as a way
>>>>> to document what variables are supposed to contain.
>>>> Where are those variables coming from?
>>>>
>>>> The distinction really boils down to this:
>>>>
>>>> * asserts should never fail. If there is any chance that an assertion
>>>> might fail outside of test suites, then don't use assert.
>>>>
>>> I'm no expert, but the more I read this thread, and the more I think on
>>> it, the more I believe that asserts don't really need to exist outside
>>> of test suites.
>> Actually, there is a good argument that one shouldn't use an assert statement in
>> test suites: code can have bugs that only show up under -O so you want to be
>> able to run your test suite under -O.
>>
>
> That's an interesting point.  Presumably TestCase.assert_() doesn't
> suffer from this defect?  Otherwise the entire unittest suite is
> essentially broken by your argument.

It explicitly raises AssertionErrors. It does not use the assert statement.

> I suppose I should have said one
> should only raise AssertionErrors in test suites.  Practically speaking,
> that's what a test suite is:  The place where you assert what the code
> does.

Yup.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From mgi820 at motorola.com  Fri Jul 10 15:03:49 2009
From: mgi820 at motorola.com (Gary Duzan)
Date: Fri, 10 Jul 2009 19:03:49 +0000 (UTC)
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
Message-ID: <h383al$pln$1@engnntp2.cig.mot.com>

In article <3af970b1-b454-4d56-a33f-889ecfacacc5 at l28g2000vba.googlegroups.com>,
Bryan  <bryanvick at gmail.com> wrote:
>
>rsyncExec = '/usr/bin/ssh'
>source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
>dest = '/home/bry/tmp'
>rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

   I think you want -e and the ssh command to be separate args.
Something like:

rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source, dest]

or:

rshArgs = [ '-e', '/usr/bin/ssh -i /home/bry/keys/brybackup.key' ]
args = [rsyncExec, '-a', '-v', '--dry-run'] +  rshArgs + [ source, dest]

					Gary Duzan
					Motorola H&NM




From clp2 at rebertia.com  Fri Jul 10 15:11:12 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 12:11:12 -0700
Subject: Colour of output text
In-Reply-To: <h371ba$36l$1@aioe.org>
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
Message-ID: <50697b2c0907101211u5d6ddc80ra85857075c986217@mail.gmail.com>

On Fri, Jul 10, 2009 at 2:23 AM,
<garabik-news-2005-05 at kassiopeia.juls.savba.sk> wrote:
> Tim Harig <usernet at ilthio.net> wrote:
>> On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
>>> I would like to learn a way of changing the colour of a particular
>>> part of the output text. I've tried the following
>
>> On Unix operating systems this would be done through the curses interface:
>>
>> http://docs.python.org/library/curses.html
>
> Or using ANSI colour codes:
>
> colours = {
<snip>
> ? ? ? ? ? ?'beep' ? ? ? : ? ?"\007",

Sound is a color? Maybe if you have synaesthesia...

Cheers,
Chris
-- 
http://blog.rebertia.com


From walterbyrd at iname.com  Fri Jul 10 15:22:15 2009
From: walterbyrd at iname.com (walterbyrd)
Date: Fri, 10 Jul 2009 12:22:15 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
Message-ID: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>

I believe Guido himself has said that all indentions should be four
spaces - no tabs.

Since backward compatibility is being thrown away anyway, why not
enforce the four space rule?

At least that way, when I get python code from somebody else, I would
know what I am looking at, without having to do a hex dump, or
something.


From marty.musatov at gmail.com  Fri Jul 10 15:24:27 2009
From: marty.musatov at gmail.com (Musatov)
Date: Fri, 10 Jul 2009 12:24:27 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
	<h36ki102d7m@news5.newsguy.com> <k%I5m.34251$Db2.2196@edtnps83>
Message-ID: <eec04d53-5eef-47ae-af91-256afe46ee38@l5g2000vbp.googlegroups.com>



Fran?ois Grondin wrote:
> "David Bernier" <david250 at videotron.ca> a ?crit dans le message de news:
> h36ki102d7m at news5.newsguy.com...
> > Musatov wrote:
> >> On Jul 9, 7:54 pm, David Bernier <david... at videotron.ca> wrote:
> >>> Musatov wrote:
> >>>> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> >>>> its adopted use in Pakistan.  The search engine has grown in
> >>>> popularity 10,000 fold following its Beta test launch three months ago
> >>>> in April, 2009. Supporters of the site claim it is better than rival
> >>>> Google upon which platform it is based. Controversy arose after
> >>>> MeAmI.org search code allowed users to search other users Google
> >>>> results with no advertising. "It is truly an innovative thing we are
> >>>> doing," said Founder and CEO, Martin Musatov. "Letting users search
> >>>> the results of other Google users immediately results in a level of
> >>>> accuracy and relevance above and beyond Google." Google changed their
> >>>> API following the launch or MeAmI.org and explored the possibility of
> >>>> blocking site access from MeAmI.org to Google search results but was
> >>>> unable to do so. Critics of MeAmI.org say what it is doing is
> >>>> tantamount to intellectual theft. When asked about this topper Musatov
> >>>> exclaimed, "The Internet was made for people, not companies." An
> >>>> analyst at Goldman Sachs says, requesting to remain anonymous,
> >>>> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> >>>> global activism and to tell you the truth, this makes it much more
> >>>> likely an acquisition target than potential intellectual property
> >>>> violator." Google could not be reached for comment.
> >>> Mr. Musatov,  do you know who originally wrote the
> >>> article above?
> >>>
> >>> Thank you.
> >>>
> >>> David Bernier- Hide quoted text -
> >>>
> >>> - Show quoted text -
> >>
> >> Yes.
> >
> > Mr. Musatov, do you know the name of the person who
> > originally wrote the article above?
> >
> > Thank you.
> >
> > David Bernier
>
> Maybe Mr. Musatov should answer the following questions instead :
> 1. Did you write the article above?
> 2. If not, who did? And I don't want AP as the answer, but the name of the
> journalist.
>
> David, don't take it bad, but he answered your question with an accurate
> answer (yes), You gave him the opportunity to avoid the real answer and he
> took it. Based on Musatov's strange behavior and logic, don't expect more
> from him. Ask anyone else the same question and you'd get a real answer.
>
> BTW, my guess for question 2 would be the Masked Logician, Floetry,
> scriber77, or Professor X.
>
> Francois
1. Yes.


From aahz at pythoncraft.com  Fri Jul 10 15:26:14 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 12:26:14 -0700
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <h384km$p5j$1@panix3.panix.com>

In article <260f0f1f-1115-4db8-a955-74c9f459ecc3 at h30g2000vbr.googlegroups.com>,
walterbyrd  <walterbyrd at iname.com> wrote:
>
>I believe Guido himself has said that all indentions should be four
>spaces - no tabs.
>
>Since backward compatibility is being thrown away anyway, why not
>enforce the four space rule?

Probably the main reason is that Guido also hates non-functional code
changes because it messes up version history.  Not sure, though.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From kwmsmith at gmail.com  Fri Jul 10 15:29:09 2009
From: kwmsmith at gmail.com (Kurt Smith)
Date: Fri, 10 Jul 2009 14:29:09 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <c266a7930907101229g6ca75d24o94c243bafb28b51e@mail.gmail.com>

On Fri, Jul 10, 2009 at 2:22 PM, walterbyrd<walterbyrd at iname.com> wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.
>
> Since backward compatibility is being thrown away anyway, why not
> enforce the four space rule?
>
> At least that way, when I get python code from somebody else, I would
> know what I am looking at, without having to do a hex dump, or
> something.

What you propose has already been (forcefully) rejected:

http://www.python.org/dev/peps/pep-0666/


From clp2 at rebertia.com  Fri Jul 10 15:29:59 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 12:29:59 -0700
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <50697b2c0907101229l720e9c92y94a921dc5c58de52@mail.gmail.com>

On Fri, Jul 10, 2009 at 12:22 PM, walterbyrd<walterbyrd at iname.com> wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.

That's a (very good) recommendation at most.
http://www.python.org/dev/peps/pep-0666/

Cheers,
Chris
-- 
http://blog.rebertia.com


From tjreedy at udel.edu  Fri Jul 10 15:30:04 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 15:30:04 -0400
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <h384rr$asn$1@ger.gmane.org>

jhinak sen wrote:
> hi,
> i am a beginner in python language,

Welcome to Python.
> 
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the 
> mean and sum in some other file :

This is three things: input data from, perform calculation, output data 
to file. I would start simpler. See below.

You did two things right that too many people do not do.

1. You posted a complete chunk of code.

> ""
> *#! /usr/bin/env python
> 
> import re
> import cPickle as p
> import math
> from numpy import *

You never use these.
> 
> f0= open("temp9","r+").readlines()

[snip]
> f0.close()
> f2.close()*

2. You posted the complete traceback (instead of the annoying 'program 
didn't work ;-).

> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""
> 
> please help to to find the error.

Seeing that, any of us could tell you thought f0 was a file but it was 
actually a list. Looking back up through the code, people found the 
definition -- the output of file.readlines, which is a list.

> or suggest some simpler or better way

Develop more incrementally. If you edit with IDLE, for instance, and hit 
RUN (F5), it takes about a second to see the result for a small program 
like this. I would have suggested starting with

data = [(1,2), (3,4)]
...
print "input: ", a, b, "output: ", tot, ave

and fill in ... until the output was correct.

Then change data to ['1 2', '3 4'] and revise until correct.

At that point, change data to open(....) and the program should 
otherwise work without change because a list of strings and a file are 
both iterators that produce a sequence of strings.

Now, if you want, worry about formating the output, removing the echo of 
the input.

Very last, send to output to a disk file instead of the screen. For 
development, that is a nuisance because it takes time to open the file 
to check results. So only do that when you already know the results are 
correct. Note that real programs used repeatedly ofter do not hard code 
an output file. If run from a command line in a comman window, screen 
output can be redirected to a file with '>': "myprog > outfile".

Terry Jan Reedy



From piet at cs.uu.nl  Fri Jul 10 15:43:21 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 10 Jul 2009 21:43:21 +0200
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
Message-ID: <m2iqi08gti.fsf@cs.uu.nl>

>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:

>CR> On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
>>> I am trying to automate rsync to backup server A from server B. ?I
>>> have set up a private/public key between the two servers so I don't
>>> have to enter a password when using rsync. ?Running rsync manually
>>> with the following command works fine:
>>> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>>> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>>> 
>>> But when I try to do it with python, the subprocess simply returns the
>>> ssh -h output on stderr like I am passing some invalid syntax. ?What
>>> is wrong in my translation of rsync's -e command from shell to
>>> pythyon?
>>> 
>>> #! /usr/bin/python
>>> from subprocess import Popen, PIPE
>>> rsyncExec = '/usr/bin/ssh'
>>> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
>>> dest = '/home/bry/tmp'
>>> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

>CR> Like many problems involving the subprocess module, I think you've
>CR> tokenized the arguments incorrectly. Try:

>CR> rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>CR> args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]

>CR> Note that the -e switch and its operand are separate arguments for the
>CR> purposes of POSIX shell tokenization.

I think you should have only one kind of quotes in rshArg:
rshArg = "/usr/bin/ssh -i /home/bry/keys/brybackup.key"

I haven't tried it, however, but this is just how Unix works.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From clp2 at rebertia.com  Fri Jul 10 15:47:59 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 12:47:59 -0700
Subject: Automate rsync w/ authentication
In-Reply-To: <m2iqi08gti.fsf@cs.uu.nl>
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
	<m2iqi08gti.fsf@cs.uu.nl>
Message-ID: <50697b2c0907101247g274c270bocfda4e82d3fb6617@mail.gmail.com>

On Fri, Jul 10, 2009 at 12:43 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:
>
>>CR> On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
>>>> I am trying to automate rsync to backup server A from server B. ?I
>>>> have set up a private/public key between the two servers so I don't
>>>> have to enter a password when using rsync. ?Running rsync manually
>>>> with the following command works fine:
>>>> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>>>> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>>>>
>>>> But when I try to do it with python, the subprocess simply returns the
>>>> ssh -h output on stderr like I am passing some invalid syntax. ?What
>>>> is wrong in my translation of rsync's -e command from shell to
>>>> pythyon?
>>>>
>>>> #! /usr/bin/python
>>>> from subprocess import Popen, PIPE
>>>> rsyncExec = '/usr/bin/ssh'
>>>> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
>>>> dest = '/home/bry/tmp'
>>>> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>>> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
>
>>CR> Like many problems involving the subprocess module, I think you've
>>CR> tokenized the arguments incorrectly. Try:
>
>>CR> rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>CR> args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]
>
>>CR> Note that the -e switch and its operand are separate arguments for the
>>CR> purposes of POSIX shell tokenization.
>
> I think you should have only one kind of quotes in rshArg:
> rshArg = "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>
> I haven't tried it, however, but this is just how Unix works.

Ah, indeed, I think you're probably right. Just goes to show it's not
always easy to get exactly right.

Cheers,
Chris
-- 
http://blog.rebertia.com


From jcd at sdf.lonestar.org  Fri Jul 10 16:12:11 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 16:12:11 -0400
Subject: Nested Classes and Instances
In-Reply-To: <m3r5woh3s4.fsf@uriel.graune.org>
References: <m3r5woh3s4.fsf@uriel.graune.org>
Message-ID: <1247256731.11457.76.camel@aalcdl07>

On Fri, 2009-07-10 at 19:00 +0200, Manuel Graune wrote:
> Hello,
> 
> as an example of what I would like to achieve, think of a street
> where each house has a door and a sign with a unique (per house)
> number on it. I tried to model this like this:
> 
> class House(object):
>     class Door(object):
>         def __init__(self,color):
>              self.color=color
>     class Sign(object):
>         def __init__(self,text):
>              self.text=text
>     def __init__(self, doorcolor,housenumber):
>         self.housenumber=housenumber
>         self.door=House.Door(doorcolor)
>         self.sign=House.Sign(housenumber)
> 
> house1=House("red","1")
> house2=House("blue","2")
> 

Don't do it like that.  Keep your classes independent.  Many houses can
have doors, and there's no reason to redefine the concept of Doors for
each one.  Same goes for Signs.  

class House(object):
    def __init__(self, doorcolor, housenumber):
        self.door = Door(doorcolor)
        self.sign = Sign(housenumber)
        self.number = housenumber

class Door(object):
    def __init__(self, color):
        self.color = color

class Sign(object):
    def __init__(self, inscription):
        self.inscription = str(housenumber)



(Something like that)

Cheers,
Cliff




> Well, so far, so good. Now, what I'd like to achive is that the text of
> the "sign" changes whenever the variable "housenumber" of the
> "parent-instance" changes or  that
> "house1.sign.text" is a reference/pointer to "house1.housenumber"
> 
> Thanks in advance,
> 
> Manuel
> 
> 
> 
> -- 
> A hundred men did the rational thing. The sum of those rational choices was
> called panic. Neal Stephenson -- System of the world
> http://www.graune.org/GnuPG_pubkey.asc
> Key fingerprint = 1E44 9CBD DEE4 9E07 5E0A  5828 5476 7E92 2DB4 3C99



From bryanvick at gmail.com  Fri Jul 10 16:16:02 2009
From: bryanvick at gmail.com (Bryan)
Date: Fri, 10 Jul 2009 13:16:02 -0700 (PDT)
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
	<m2iqi08gti.fsf@cs.uu.nl>
Message-ID: <f370a703-2864-471f-bab4-4774981458ce@b14g2000yqd.googlegroups.com>

On Jul 10, 12:43?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Chris Rebert <c... at rebertia.com> (CR) wrote:
> >CR> On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanv... at gmail.com> wrote:
> >>> I am trying to automate rsync to backup server A from server B. ?I
> >>> have set up a private/public key between the two servers so I don't
> >>> have to enter a password when using rsync. ?Running rsync manually
> >>> with the following command works fine:
> >>> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
> >>> r... at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>
> >>> But when I try to do it with python, the subprocess simply returns the
> >>> ssh -h output on stderr like I am passing some invalid syntax. ?What
> >>> is wrong in my translation of rsync's -e command from shell to
> >>> pythyon?
>
> >>> #! /usr/bin/python
> >>> from subprocess import Popen, PIPE
> >>> rsyncExec = '/usr/bin/ssh'
> >>> source = 'r... at 10.0.45.67:/home/bry/jquery.lookup'
> >>> dest = '/home/bry/tmp'
> >>> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> >>> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
> >CR> Like many problems involving the subprocess module, I think you've
> >CR> tokenized the arguments incorrectly. Try:
> >CR> rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> >CR> args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]
> >CR> Note that the -e switch and its operand are separate arguments for the
> >CR> purposes of POSIX shell tokenization.
>
> I think you should have only one kind of quotes in rshArg:
> rshArg = "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>
> I haven't tried it, however, but this is just how Unix works.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

I tried removing the internal quotes, and splitting '-e' from the
other arguments.  I still get the same ssh -h output however:

rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source,
dest]
p = Popen(args, stdout=PIPE, stderr=PIPE)



From tjreedy at udel.edu  Fri Jul 10 16:27:12 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:27:12 -0400
Subject: tough-to-explain Python
In-Reply-To: <pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2931.1247195266.8015.python-list@python.org>
	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
Message-ID: <h3886v$ki0$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Thu, 09 Jul 2009 23:07:34 -0400, Terry Reedy wrote:

>>
>> The is *not* a bug is Bentley program.

This is *not* a bug in Bentley's program.

> Wow. That's an impressive set of typos :)

3. Way beneath my usual standards ;-)

>> It is a bug in bad, buggy, insane
>> integer arithmetic implementations. low + high should either return the
>> right answer, as it will in Python, or raise an overflow error.
> 
> Is binary search *supposed* to raise an overflow error if given more than 
> 2**30 elements? 

No. it is supposed to work, and Bentley's program will work if lo and hi 
are actually integers, as his program presupposes, and not residue 
classes mislabeled 'int'.

> Is there something special about OverflowError that is "better" than 
> ArrayIndexOutOfBoundsException?

Wrong comparison. The actual alternative to OverflowError is a negative 
number as the sum of two positive numbers. If one claims that a and b 
are positive ints, then returning a negative is a bug. The index 
exception was a side effect, in Java, of using the negative as an index. 
In C, the side effect was a segmentation fault. Do you seriously 
question that OverflowError is better than seg faulting? A different 
program could go on to silently return a wrong answer. Perhaps it would 
say to go west instead of east, or to reduce a medical dosage instead of 
raising it.

Note that negative ints are legal indexes in Python, so that if any 
Python version ever had ints that wrapped instead of overflowing or 
returning a long, then the program would not necessarily stop.

> but there's no reason to imagine that the book will assume -- or even 
> state as a requirement for binary search -- that addition will never 
> overflow.

Bentley assumed that if (lo+hi)/2 were successfully calculated, then it 
would be a positive number between lo and hi, and therefore a legal index.

The dirty secret of computing is that some languages do not have integer 
types. They do not even have restricted-range integer types, which would 
noisily fail when they cannot perform an operation. They only have 
residue class types, which are something else, and which can give 
bizarre results if one mindlessly uses them as if they really were 
restricted-range integers. When one wants integer operations, every 
operation with two residue-class variables has a potential *silent* bug. 
Being relieved of the burden of constantly keeping this in mind is one 
reason I use Python.

Float types are usually restricted range types. A huge_float + 
huge_float may raise overflow, but never returns a negative float.

Bentley assumed that indexes hi and lo are integers. If one uses 
restricted range integers that are too large, then lo+hi could fail 
gracefully with an appropriate effor message. I would not consider that 
a bug, bug a limitation due to using limited-range numbers. If one uses 
residue classes instead of integers, and makes no adjustment, I consider 
it wrong to blame Bentley.

Terry Jan Reedy



From vivainio at gmail.com  Fri Jul 10 16:30:37 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Fri, 10 Jul 2009 13:30:37 -0700 (PDT)
Subject: ANN: Leo 4.6 rc1 released
References: <D8M5m.54324$c82.37596@newsfe08.iad>
Message-ID: <56d676ba-b2fc-4288-a37e-0825291369e0@n11g2000yqb.googlegroups.com>

On Jul 10, 9:54?pm, "Edward K Ream" <edream... at charter.net> wrote:

> The highlights of Leo 4.6:
> --------------------------

> - Leo now features a modern Qt interface by default.
> ? Leo's legacy Tk interface can also be used.

And to drive home this point (Qt ui), some screenshots for the
visually oriented:

http://imgbin.org/images/625.png
http://imgbin.org/images/626.png
http://imgbin.org/images/627.png


From tjreedy at udel.edu  Fri Jul 10 16:32:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:32:17 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <4A572AA1.7010207@ieee.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>	<4A55F392.3080404@ieee.org>	<h35a1h$gus$1@ger.gmane.org>
	<4A572AA1.7010207@ieee.org>
Message-ID: <h388gg$lf8$1@ger.gmane.org>

Dave Angel wrote:
> Terry Reedy wrote:

> If you mean dis.dis() that only gives you byte code.

No, dis is a disassembler and it gives readable assembly code, not the 
raw numerical bytes. Its purpose is to make byte code + other parts of 
the code object humanly readable.

As far as I know, there is no assembler that would turn the exact output 
of dis back to its input.

tjr



From Scott.Daniels at Acm.Org  Fri Jul 10 16:38:06 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 13:38:06 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
	<0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>
Message-ID: <muOdnciPf_tpOcrXnZ2dnUVZ_uNi4p2d@pdx.net>

Raymond Hettinger wrote:
> [Scott David Daniels]
>> def most_frequent(arr, N): ...
> In Py2.4 and later, see heapq.nlargest().
I should have remembered this one

> In Py3.1, see collections.Counter(data).most_common(n)
This one is from Py3.2, I think.


--Scott David Daniels
Scott.Daniels at Acm.Org


From tjreedy at udel.edu  Fri Jul 10 16:47:06 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:47:06 -0400
Subject: Query regarding set([])?
In-Reply-To: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
Message-ID: <h389ca$nqd$1@ger.gmane.org>

vox wrote:
> Hi,
> I'm contsructing a simple compare-script and thought I would use set
> ([]) to generate the difference output. But I'm obviosly doing
> something wrong.
> 
> file1 contains 410 rows.
> file2 contains 386 rows.
> I want to know what rows are in file1 but not in file2.
> 
> This is my script:
> s1 = set(open("file1"))
> s2 = set(open("file2"))
> s3 = set([])
> s1temp = set([])
> s2temp = set([])
> 
> s1temp = set(i.strip() for i in s1)
> s2temp = set(i.strip() for i in s2)
> s3 = s1temp-s2temp
> 
> print len(s3)
> 
> Output is 119. AFAIK 410-386=24. What am I doing wrong here?

Assuming that every line in s2 is in s1. If there are lines in s2 that 
are not in s1, then the number of lines in s1 not in s2 will be larger 
than 24. s1 - s2 subtracts the intersection of s1 and s2.



From tjreedy at udel.edu  Fri Jul 10 16:53:53 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:53:53 -0400
Subject: problem with keys combination!
In-Reply-To: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
Message-ID: <h389p0$oph$1@ger.gmane.org>

Alex wrote:
> Hi at all,
>   I made a simple program that make a screenshot of Desktop and use it
> as fullscreen background and then a ball erase image making illusion
> that erase Desktop. The program working fine and I succesfully blocked
> all keys but I have a problem with hotkey combination Ctrl-Alt-
> Del...that bypass my FullScreen Application.

Blocking Ctrl-Alt-Del leaves the power switch or maybe the plug as the 
only way for the user to regain control. Why would you want to do that?



From ivlenin at gmail.com  Fri Jul 10 16:54:08 2009
From: ivlenin at gmail.com (I V)
Date: 10 Jul 2009 22:54:08 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2931.1247195266.8015.python-list@python.org>
	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
	<mailman.2983.1247257646.8015.python-list@python.org>
Message-ID: <4a57aa70@news.x-privat.org>

On Fri, 10 Jul 2009 16:27:12 -0400, Terry Reedy wrote:
> a bug, bug a limitation due to using limited-range numbers. If one uses
> residue classes instead of integers, and makes no adjustment, I consider
> it wrong to blame Bentley.

But it was Bentley himself who used the C int type, so it hardly seems 
unreasonable to blame him.


From Scott.Daniels at Acm.Org  Fri Jul 10 17:07:28 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 14:07:28 -0700
Subject: Sorry about that, the Counter class is there.
In-Reply-To: <muOdnciPf_tpOcrXnZ2dnUVZ_uNi4p2d@pdx.net>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
	<0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>
	<muOdnciPf_tpOcrXnZ2dnUVZ_uNi4p2d@pdx.net>
Message-ID: <UaSdnRCTVf5KNsrXnZ2dnUVZ_uKdnZ2d@pdx.net>

Scott David Daniels wrote:
> Raymond Hettinger wrote:
>> [Scott David Daniels]
>>> def most_frequent(arr, N): ...
>> In Py2.4 and later, see heapq.nlargest().
> I should have remembered this one
> 
>> In Py3.1, see collections.Counter(data).most_common(n)
> This one is from Py3.2, I think.

Oops -- egg all over my face.  I thought I was checking with 3.1, and it
was 2.6.2.  I _did_ make an explicit check, just poorly.

Again, apologies.

--Scott David Daniels
Scott.Daniels at Acm.Org


From noen  Fri Jul 10 17:16:13 2009
From: noen (earthlink)
Date: Fri, 10 Jul 2009 17:16:13 -0400
Subject: 2.4 VS 3.1 for simple print
Message-ID: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>

Why does 

print "GarbageCollector: collected %d objects." % (gc.collect())

work in 2.4 but not in 3.1?


From Scott.Daniels at Acm.Org  Fri Jul 10 17:24:42 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 14:24:42 -0700
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <h37eat$qmm$1@lec.cs.unibo.it>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
	<h37eat$qmm$1@lec.cs.unibo.it>
Message-ID: <BbWdnQyDurB8MsrXnZ2dnUVZ_j6dnZ2d@pdx.net>

jacopo mondi wrote:
> Roger Binns wrote:
>> jacopo mondi wrote:
>>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>>> add support to an experimental socket family.
>> You may find it considerably easier to use ctypes since that will avoid
>> the need for any patching.  You'll also be able to control how read and
>> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
>> os.fdopen to convert your raw file descriptor into a Python file object
>> if appropriate.

The typical Python way of dealing with this is an additional module, not
a modified module placed back in the library.  So, take the sources and
edit, but change the module name.  Even better is figure out how to
use _socket.pyd, to create a smaller _socketexpmodule.c and use that.

--Scott David Daniels
Scott.Daniels at Acm.Org


From clp2 at rebertia.com  Fri Jul 10 17:28:07 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 14:28:07 -0700
Subject: 2.4 VS 3.1 for simple print
In-Reply-To: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
Message-ID: <50697b2c0907101428q76fcef47me9e389c5aeee66f3@mail.gmail.com>

On Fri, Jul 10, 2009 at 2:16 PM, earthlink<noen> wrote:
> Why does
> print "GarbageCollector: collected %d objects." % (gc.collect())
>
> work in 2.4 but not in 3.1?

Define "works". What error are you getting? Include the exact message
and full error traceback.
Or if no exception is being raised, explain exactly how is it behaving
differently from your expectations.

Cheers,
Chris
-- 
http://blog.rebertia.com


From martin at v.loewis.de  Fri Jul 10 17:30:53 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Fri, 10 Jul 2009 23:30:53 +0200
Subject: 2.4 VS 3.1 for simple print
In-Reply-To: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
Message-ID: <4a57b30e$0$15912$9b622d9e@news.freenet.de>

> Why does
> print "GarbageCollector: collected %d objects." % (gc.collect())
> 
> work in 2.4 but not in 3.1?

Because print is a function in 3.1, so you have to follow it with
a parenthesis.

Regards,
Martin


From lkcl at lkcl.net  Fri Jul 10 17:37:46 2009
From: lkcl at lkcl.net (Luke Kenneth Casson Leighton)
Date: Fri, 10 Jul 2009 21:37:46 +0000
Subject: [ANN] Pyjamas 0.6pre1 ALPHA release of Pyjamas Widget Set
Message-ID: <ced5f0f60907101437t69b52b3ct5c6ae713e377a4c6@mail.gmail.com>

http://pyjs.org - Pyjamas is a port of GWT to Python that can run
applications both on the Desktop (like python-gtk2) and in all
major Web Browsers (as javascript).

This is an alpha release - 0.6pre1 - of the Pyjamas Web Widget Set.

It is a significant upgrade, incorporating Pyjamas Desktop which
can now use Mozilla XULRunner as well as PyWebKitGtk as the
browser engine.
Significant enhancements have been made to the javascript
compiler, which bring python strict features as well as a
relaxed (and faster) compile-time option.

The reason for the 0.6 pre-release is due to the number of
features and improvements added.

Many thanks to Kees, Lovely Systems, and all the people from
EuroPython 2009 who have helped contribute and generally make
Pyjamas fun to work with.

Downloads are available from:
http://code.google.com/p/pyjamas
http://sourceforge.net/projects/pyjamas
http://pypi.python.org/pypi/Pyjamas


From matt.dubins at sympatico.ca  Fri Jul 10 17:39:14 2009
From: matt.dubins at sympatico.ca (inkhorn)
Date: Fri, 10 Jul 2009 14:39:14 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
Message-ID: <e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>

Thanks all!!  I found the following to be most helpful:  any(substr in
long_string for substr in list_of_strings)

This bang-for-your-buck is one of the many many reasons why I love
Python programming :)

Matt Dubins


From piet at cs.uu.nl  Fri Jul 10 17:46:23 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 10 Jul 2009 23:46:23 +0200
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
	<m2iqi08gti.fsf@cs.uu.nl>
	<f370a703-2864-471f-bab4-4774981458ce@b14g2000yqd.googlegroups.com>
Message-ID: <m2ab3c8b4g.fsf@cs.uu.nl>

>>>>> Bryan <bryanvick at gmail.com> (B) wrote:

>B> I tried removing the internal quotes, and splitting '-e' from the
>B> other arguments.  I still get the same ssh -h output however:

>B> rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
>B> args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source,
>B> dest]
>B> p = Popen(args, stdout=PIPE, stderr=PIPE)

For me it works. Of course I substituted local server names, file names
etc. I run this on Mac OS X 10.4.11. The server is some Linux system.

------------------------------------------------------------------------
#! /usr/bin/env python

from subprocess import Popen, PIPE
rsyncExec = '/usr/local/bin/rsync'

source = 'xxx.cs.uu.nl:/users/piet/yyyyyy'
dest = '/Users/piet/TEMP/test.rsync'

rshArg = '/usr/bin/ssh -i /Users/piet/.ssh/id_rsa'

args = [rsyncExec, '-a', '-v', '-e', rshArg, source, dest]

try:
	p = Popen(args, stdout=PIPE, stderr=PIPE)
	print 'rsync running with pid %s' % p.pid
	out, err = p.communicate()
	print 'Errors: %s' % err
	print 'Output: %s' % out
except Exception:
	print 'Error running rsync'
------------------------------------------------------------------------

It just copies the file.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From timlee126 at yahoo.com  Fri Jul 10 17:52:09 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 10 Jul 2009 14:52:09 -0700 (PDT)
Subject: main in Python
Message-ID: <159869.41728.qm@web63104.mail.re1.yahoo.com>


Hi,
I learned that a Python script is written in this way:
def main():
    ...
if __name__ == "__main__":
    main()

Today, when I read a script, I found it has a different way:

def main():
    ...

main()

It can run as well. Can someone explain why and the rules that Python scripts get run?

Thanks and regards,
Tim


      


From jjposner at optimum.net  Fri Jul 10 18:01:06 2009
From: jjposner at optimum.net (John Posner)
Date: Fri, 10 Jul 2009 18:01:06 -0400
Subject: Tkinter only: table widget with canvas...
In-Reply-To: <mailman.10638.1247239202.8014.python-list@python.org>
References: <mailman.10638.1247239202.8014.python-list@python.org>
Message-ID: <4A57BA22.5030201@optimum.net>

Hi --
>
> a) Assume I would have some different widgets to add per row. How
>     do I get the maximum row height?

If you are placing widgets in a table like this:

  w.grid(row=a, column=b)

... where the *master* of widget "w" is a Tkinter.Frame named 
"table_frm", then you can determine the height of row N like this:

   table_frm.grid_bbox(column=0, row=N)

Quoth the grid_bbox() documentation (with the object name changed for 
clarity):

    Returns a 4-tuple describing the bounding box of some or all
    of the grid system in widget |/|table_frm|/|. The first two numbers 
returned
    are the /|x|/ and /|y|/ coordinates of the upper left corner of the 
area,
    and the second two numbers are the width and height.


So the final member of the 4-tuple is the height you want.
>
> b) Assume something like a label in one column. The length of all
> texts
>     in a column will differ. How do I choose the maxium column width?

The third member of grid_bbox() 4-tuple is the cell-width. So just find 
the maximum of these values:

   table_frm.grid_bbox(column=0, row=0)[2]
   table_frm.grid_bbox(column=1, row=0)[2]
   table_frm.grid_bbox(column=2, row=0)[2]
   ...

>
> c) Placing headers in a canvas does not look like a good idea because
>     I don't want to scroll the headers. Am I right?
>     c.1) How do I place a none scrollable header in a canvas?  or
>     c.2) How do I place all headers outside the canvas correctly above
> the relating column?
>

"c.2" is what you want. Again, if the table is in a Tkinter.Frame named 
"frm", you want to create an outer frame, then pack a header frame and 
the table frame into it, vertically:

    rt = Tk()
    outer_frm = Frame(rt)
    outer_frm.pack(expand=True, fill=BOTH)
    header_frm = Frame(outer_frm, height=25)
    header_frm.pack(side=TOP)
    table_frm = Frame(outer_frm)
    table_frm.pack(side=TOP)


(For scrolling, consider making "table_frm" a Pmw.ScrolledFrame instead 
of a Tkinter.Frame.)

As for getting the heading labels correctly placed above the columns, 
pack correctly-sized subframes (Tkinter.Frame's) into "header_frm". To 
determine the size of a column, use grid_bbox() again:

    BBOX_WIDTH_COMPONENT = 2
    header_subfrm = Frame(header_frm, relief=GROOVE, bd=2)
    header_subfrm['width'] = \
         table_frm.grid_bbox(column=N, row=0)[BBOX_WIDTH_COMPONENT]
  
Then, use place() to center a label within the subframe:

    header_label = Label(header_subfrm, text="Heading")
    header_label.place(relx=0.5, rely=0.5, anchor=CENTER)

There's a working app at http://cl1p.net/tkinter_table_headers/

-John




From ethan at stoneleaf.us  Fri Jul 10 18:11:08 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 10 Jul 2009 15:11:08 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006eb26f$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<h2nqpf$d91$1@reader1.panix.com>	<mailman.2688.1246883548.8015.python-list@python.org>	<006e795f$0$9711$c3e8da3@news.astraweb.com>	<h2uhcb$blq$1@panix3.panix.com>
	<006eb26f$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <4A57BC7C.5030705@stoneleaf.us>

Steven D'Aprano wrote:
> On Mon, 06 Jul 2009 21:02:19 -0700, Aahz wrote:
> 
> 
>>In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>, Steven D'Aprano 
>><steve at REMOVE-THIS-cybersource.com.au> wrote:
>>
>>>On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>>>
>>>>kj wrote:
>>>>
>>>>>    sense = cmp(func(hi), func(lo))
>>>>>    assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>>>
>>>>As already said before, unlike other languages, sense in english does
>>>>**not** mean direction. You should rewrite this part using a better
>>>>name. Wrong informations are far worse than no information at all.
>>>
>>>Absolutely.
>>>
>>
>>>From Webster's Dictionary:
>>
>>>     8. (Geom.) One of two opposite directions in which a line,
>>>     surface, or volume, may be supposed to be described by the motion
>>>     of a point, line, or surface.
>>>     [1913 Webster]
>>>
>>>
>>>And from WordNet:
>>>
>>>    2: the meaning of a word or expression; the way in which a word
>>>       or expression or situation can be interpreted
>>>
>>>Both meanings are relevant to the way KJ is using the word. Please take
>>>your own advice and stop giving wrong information. As a native English
>>>speaker, I had no difficulty understanding the meaning of "sense" in the
>>>sense intended by KJ.
>>
>>As another native English speaker, I agree with Jean-Michel; this is the
>>first time I've seen "sense" used to mean direction.
> 
> 
> 
> Just goes to show you learn something new all the time.
> 
> http://www.merriam-webster.com/dictionary/sense
> 
>     7: one of two opposite directions especially of motion (as 
>     of a point, line, or surface)
> 
> 
> http://dictionary.reference.com/browse/sense
> 
>     18.  Mathematics. one of two opposite directions in which 
>     a vector may point.
> 
> 
> 
> Paraphrasing the Collins Dictionary of Mathematics:
> 
> The sense of a vector is the sign of the measure, contrasted with the 
> magnitude. Thus the vectors AB and BA have the same direction but 
> opposite sense. Sense is also used to distinguish clockwise and anti-
> clockwise.
> 
> Sense is, if you like, a "signed direction". "Towards north" (say) as 
> opposed to "along the north-south axis".
> 

This also illustrates the importance of knowing your target audience.  I 
have also not seen "sense" used this way before, and from the placement 
in the dictionaries I would venture to say it's not common usage outside 
of mathematics and the sciences.

Of course, since kj is teaching biologists, odds are decent they know 
what he's talking about.

~Ethan~


From usernet at ilthio.net  Fri Jul 10 18:13:00 2009
From: usernet at ilthio.net (Tim Harig)
Date: Fri, 10 Jul 2009 22:13:00 GMT
Subject: main in Python
References: <mailman.2989.1247263131.8015.python-list@python.org>
Message-ID: <M1P5m.3484$Ad2.405@nlpi067.nbdc.sbc.com>

On 2009-07-10, Tim <timlee126 at yahoo.com> wrote:
[RE-ORDERED]
> It can run as well. Can someone explain why and the rules that Python
> scripts get run?

Everything gets run by default.  The def syntax defines functions but does
not run them -- they are only run when they are called

> Today, when I read a script, I found it has a different way:
> def main():
>     ...
>
> main()

This define main and then runs it.

> def main():
>     ...
> if __name__ == "__main__":
>     main()

This defines main but it only runs it if __name__ == "__main" which will
only happen if the script is called directly:

./sample.py
or
python sample.py
etc.

This form is often preferred because it allows you to import definitions
the module without running the code within the main funciton module.
That way the same file can be used as a standalone program or as an
importable module.


From david250 at videotron.ca  Fri Jul 10 18:26:36 2009
From: david250 at videotron.ca (David Bernier)
Date: Fri, 10 Jul 2009 18:26:36 -0400
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
Message-ID: <h38f6t01fj2@news7.newsguy.com>

scriber77 at yahoo.com wrote:
[...]

> community. But perhaps he is trying to see things a bit differently
> and is just not getting the feedback he needs, so he is throwing
> tantrums apparently across USENET.
> 
> Like I said before, I am just trying to do right by this person who
> contacted me, and seemed to be a decent person with a genuine interest
> in mathematics. He was very respectful.
> 
> Alas, I am at a loss on what specific feedback to give him on his
> paper as though I am a professor of Mathematics, Computer Science is
> not my specialty.
> 
> I told him I would try to get him some feedback on the equations on
> page 3.  Would any of you be so kind to help me?
> 
> Here is the paper: http://MeAmI.org/pversusnp.pdf
> 
> I do thank you for your time.
> 
> Good day,
> 
> Professor X

This is what there is at the bottom of page 3:

<< Conclusion: Binary revisions are allowed given the above formulas. >>

So I don't understand the proposed solution for the "P = NP"
problem.

David Bernier


From liukis at usc.edu  Fri Jul 10 19:28:06 2009
From: liukis at usc.edu (Maria Liukis)
Date: Fri, 10 Jul 2009 16:28:06 -0700
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty"
	exception
Message-ID: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>

Hello,

Has anybody seen an exception "OSError: [Errno 39] Directory not  
empty" raised by shutil.rmtree? The code that raised an exception  
creates a lot of directories with files, and then removes them. I got  
an exception when one of such directories was removed. Here is the  
backtrace:

     shutil.rmtree(filename)
   File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
     onerror(os.rmdir, path, sys.exc_info())
   File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
     os.rmdir(path)
OSError: [Errno 39] Directory not empty: /path/to/my/dir

According to the documentation, shutil.rmtree should not care about  
directory being not empty.

Thanks for the help,
Masha
--------------------
liukis at usc.edu



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/557f5e85/attachment.html>

From ben+python at benfinney.id.au  Fri Jul 10 19:35:13 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 11 Jul 2009 09:35:13 +1000
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <87ljmwm7ri.fsf@benfinney.id.au>

walterbyrd <walterbyrd at iname.com> writes:

> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.

Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
with a simple imperative::

    Use 4 spaces per indentation level.

it soon afterward takes a more nuanced tone::

    The most popular way of indenting Python is with spaces only. The
    second-most popular way is with tabs only. Code indented with a
    mixture of tabs and spaces should be converted to using spaces
    exclusively. When invoking the Python command line interpreter with
    the -t option, it issues warnings about code that illegally mixes
    tabs and spaces. When using -tt these warnings become errors. These
    options are highly recommended!

    For new projects, spaces-only are strongly recommended over tabs.
    Most editors have features that make this easy to do.

    <URL:http://www.python.org/dev/peps/pep-0008/>

> Since backward compatibility is being thrown away anyway

That implies a level of abandon that was (AIUI) never the intent.
Rather, backward compatibility was critically examined for whether it
was justified in Python 3.

> why not enforce the four space rule?

Guido has used his time machine to answer your question a few years ago
<URL:http://www.artima.com/weblogs/viewpost.jsp?thread=101968>. (Be sure
to read the discussion in the comments on the article.)

> At least that way, when I get python code from somebody else, I would
> know what I am looking at, without having to do a hex dump, or
> something.

Any text editor that is good for programming (yes, I'm aware this is
perilously close to a ?no true Scotsman? fallacy) will have an option
to visibly differentiate whitespace characters, for exactly the reason
you point out.

-- 
 \           ?Special cocktails for the ladies with nuts.? ?bar, Tokyo |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From ben+python at benfinney.id.au  Fri Jul 10 19:37:53 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 11 Jul 2009 09:37:53 +1000
Subject: 2.4 VS 3.1 for simple print
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
Message-ID: <87hbxkm7n2.fsf@benfinney.id.au>

"earthlink" <noen> writes:

> Why does 
> 
> print "GarbageCollector: collected %d objects." % (gc.collect())
> 
> work in 2.4 but not in 3.1?

For this and other differences introduced in the Python 3.x series, see
<URL:http://www.python.org/dev/peps/pep-3100/>.

-- 
 \     ?Please do not feed the animals. If you have any suitable food, |
  `\                     give it to the guard on duty.? ?zoo, Budapest |
_o__)                                                                  |
Ben Finney


From tjreedy at udel.edu  Fri Jul 10 19:48:58 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 19:48:58 -0400
Subject: tough-to-explain Python
In-Reply-To: <4a57aa70@news.x-privat.org>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2931.1247195266.8015.python-list@python.org>	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>	<mailman.2983.1247257646.8015.python-list@python.org>
	<4a57aa70@news.x-privat.org>
Message-ID: <h38k19$hsn$1@ger.gmane.org>

I V wrote:
> On Fri, 10 Jul 2009 16:27:12 -0400, Terry Reedy wrote:
>> a bug, bug a limitation due to using limited-range numbers. If one uses
>> residue classes instead of integers, and makes no adjustment, I consider
>> it wrong to blame Bentley.
> 
> But it was Bentley himself who used the C int type, so it hardly seems 
> unreasonable to blame him.

The original program that he verified was in pseudocode equivalent to 
the following (not tested) Python. The odd spec is due to Bentley using 
1-based arrays. From the 1986 book Programming Pearls

def binsearch(x, t):
    "If t is in sorted x[1:n], return its index; otherwise 0"
    #
    L,U = 1, len(x)-1
    while True:
       if L > U: return 0
       m = (L+U)/2
       if   x[m] <  t: L = m+1
       elif x[m] == t: return m
       elif x[m] >  t: U = m-1

He then translated into an unspecified dialect of BASIC, but it is 
consistent with Microsoft GW-BASIC. If so, L and U were float variables, 
while the largest possible array size for x was 32767. So as near as I 
can tell with that dialect, there was no possible problem with L+U 
overflowing or wrapping. Other dialects, I am not sure.

So I revise my statement to "I consider it wrong to blame the Bentley 
that wrote the original program" ;-).

If he later translated to C and fell into the residue class trap, then 
that reinforces my contention that using residue classes as ints is 
error prone.

Terry Jan Reedy



From r1chardj0n3s at gmail.com  Fri Jul 10 19:52:18 2009
From: r1chardj0n3s at gmail.com (Richard Jones)
Date: Sat, 11 Jul 2009 09:52:18 +1000
Subject: Announcing the 9th Pyweek game programming challenge!
Message-ID: <7CFED2D8-4C06-4E6F-B25D-C39A510C7686@gmail.com>

The date for the ninth PyWeek challenge has been set:

   Sunday 30th August to Sunday 6th September (00:00UTC to 00:00UTC)


The PyWeek challenge invites entrants to write a game in one week from
scratch either as an individual or in a team. Entries must be developed
in Python, during the challenge, and must incorporate some theme chosen
at the start of the challenge.


REGISTRATION IS NOT YET OPEN --

Registration will open one month before the start date. See the
competition timetable and rules:

    http://www.pyweek.org/9/


PLANNING FOR THE CHALLENGE --

Make sure you have working versions of the libraries you're going to  
use.
The rules page has a list of libraries and other resources.

Make sure you can build packages to submit as your final submission (if
you're going to use py2exe, make sure you know how to use it and that it
works).

If you don't have access to Linux, Windows or a Mac to test on, contact
friends, family or other competitors to find someone who is able to test
for you.



From ben+python at benfinney.id.au  Fri Jul 10 19:55:10 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 11 Jul 2009 09:55:10 +1000
Subject: Email provider recommendations for those tired of mangled messages
	(was: subprocess + python-daemon - bug/problem?)
References: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>
	<828acd8d-a9bd-4506-b695-e537af4587d8@l31g2000yqb.googlegroups.com>
	<873a94ojvi.fsf@benfinney.id.au>
Message-ID: <87d488m6u9.fsf_-_@benfinney.id.au>

Ben Finney <ben+python at benfinney.id.au> writes:

> Here it is without the unwanted extra line-wrapping that seems to
> plague all Google Mail users (seriously, folks: get a real mail
> provider that won't mangle your messages)

I've been asked off-list whether I have any suggestions for those who
want a better email provider. Handling email (transport and mailbox
services) is certainly a service that's worth getting someone else to
handle, provided you can trust they'll do so reliably and well. For me,
?well? includes ?don't mangle my messages?.

My personal solution to this is to manage my own email server machine,
but that's an ongoing investment of time that is not something I would
recommend to everyone.

Nancy McGough maintained (past tense? present tense?) a comprehensive
index <URL:http://www.ii.com/internet/messaging/imap/isps/#providers> of
email service providers with IMAP access, hence allowing you to use
whatever IMAP mail client you like to communicate with your mailboxes
remotely. There are feature lists and price indications for each
provider.

Several of my colleagues swear by Tuffmail <URL:http://tuffmail.com/> as
providing excellent uptime, fine control filtering, responsive service,
flexible customisation, and good overall value.

-- 
 \        ?Visitors are expected to complain at the office between the |
  `\                     hours of 9 and 11 a.m. daily.? ?hotel, Athens |
_o__)                                                                  |
Ben Finney


From nagle at animats.com  Fri Jul 10 20:02:19 2009
From: nagle at animats.com (John Nagle)
Date: Fri, 10 Jul 2009 17:02:19 -0700
Subject: tough-to-explain Python
In-Reply-To: <a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
Message-ID: <4a57d630$0$1646$742ec2ed@news.sonic.net>

Bearophile wrote:
> kj, as Piet van Oostrum as said, that's the difference between mutable
> an immutable. It comes from the procedural nature of Python, and
> probably an explanation of such topic can't be avoided if you want to
> learn/teach Python.

     The problem with Python's mutable/immutable distinction is that
it's not very visible.  In a language with no declarations, no named
constants, and no parameter attributes like "value", "in", "out", or
"const", it's not at all obvious which functions can modify what.
Which is usually the place where this causes a problem.

     The classic, of course, is

def additemtolist(item, lst = []) :
     lst.append(item)
     return(lst)

lista = additemtolist(1)
listb = additemtolist(2)
print(listb)

The general problem is inherent in Python's design.  This particular problem,
though, results in the occasional suggestion that parameters shouldn't
be allowed to have mutable defaults.

				John Nagle


From python.list at tim.thechases.com  Fri Jul 10 20:10:03 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 10 Jul 2009 19:10:03 -0500
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty"
	exception
In-Reply-To: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>
References: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>
Message-ID: <4A57D85B.8040305@tim.thechases.com>

>      shutil.rmtree(filename)
>    File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
>      onerror(os.rmdir, path, sys.exc_info())
>    File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
>      os.rmdir(path)
> OSError: [Errno 39] Directory not empty: /path/to/my/dir
> 
> According to the documentation, shutil.rmtree should not care about  
> directory being not empty.

This sounds suspiciously like a permission issue.  rmtree() 
*should* walk the tree removing items *if it can*.  If a file 
can't be deleted, it treats it as an error.  rmtree() takes 
parameters for ignore_errors and an onerror callback function, so 
you can catch these error conditions.

-tkc




From liukis at usc.edu  Fri Jul 10 20:30:56 2009
From: liukis at usc.edu (Maria Liukis)
Date: Fri, 10 Jul 2009 17:30:56 -0700
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty"
	exception
In-Reply-To: <4A57D85B.8040305@tim.thechases.com>
References: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>
	<4A57D85B.8040305@tim.thechases.com>
Message-ID: <A7154223-8964-431D-A90D-EE37706383A3@usc.edu>

Thanks for pointing out the parameters for ignore_errors and an  
onerror callback function.

I have been running this code for more than an year, and this is the  
very first time I see the problem. We switched to the NFS mounted  
storage though, but there is nothing unusual logged by the system in  
the /var/log/messages.

I checked the permissions - the directory is still there and has  
exactly the same permissions as other successfully copied and removed  
directories (the very same process creates the directory and later  
removes it). The directory is empty though - so the process removed  
all the entries in it, then some kind of an error occured that  
triggered the exception.

There are lots of similar directories that the process creates and  
removes, but only one of them raised an exception.

Thanks,
Masha
--------------------
liukis at usc.edu



On Jul 10, 2009, at 5:10 PM, Tim Chase wrote:

>>      shutil.rmtree(filename)
>>    File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
>>      onerror(os.rmdir, path, sys.exc_info())
>>    File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
>>      os.rmdir(path)
>> OSError: [Errno 39] Directory not empty: /path/to/my/dir
>> According to the documentation, shutil.rmtree should not care  
>> about  directory being not empty.
>
> This sounds suspiciously like a permission issue.  rmtree()  
> *should* walk the tree removing items *if it can*.  If a file can't  
> be deleted, it treats it as an error.  rmtree() takes parameters  
> for ignore_errors and an onerror callback function, so you can  
> catch these error conditions.
>
> -tkc
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/39b997aa/attachment.html>

From davea at ieee.org  Fri Jul 10 20:44:48 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 20:44:48 -0400
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <h38f6t01fj2@news7.newsguy.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>	<h36agp02ste@news7.newsguy.com>	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<h38f6t01fj2@news7.newsguy.com>
Message-ID: <4A57E080.20008@ieee.org>



David Bernier wrote:
>> <snip>
>>
>> Good day,
>>
>> Professor X
>
> This is what there is at the bottom of page 3:
>
> << Conclusion: Binary revisions are allowed given the above formulas. >>
>
> So I don't understand the proposed solution for the "P = NP"
> problem.
>
> David Bernier
>
>
"Professor X" is yet another alias for the hoaxter who started this 
thread, and presumably who created the website.




From benjamin.kaplan at case.edu  Fri Jul 10 21:25:19 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Fri, 10 Jul 2009 21:25:19 -0400
Subject: main in Python
In-Reply-To: <159869.41728.qm@web63104.mail.re1.yahoo.com>
References: <159869.41728.qm@web63104.mail.re1.yahoo.com>
Message-ID: <ec96e1390907101825v37dbfdc9qbef6d8da7595a70d@mail.gmail.com>

On Fri, Jul 10, 2009 at 5:52 PM, Tim<timlee126 at yahoo.com> wrote:
>
> Hi,
> I learned that a Python script is written in this way:
> def main():
> ? ?...
> if __name__ == "__main__":
> ? ?main()
>
> Today, when I read a script, I found it has a different way:
>
> def main():
> ? ?...
>
> main()
>
> It can run as well. Can someone explain why and the rules that Python scripts get run?
>


You're thinking like a C or Java programmer. Python scripts are just
that - scripts. They aren't compiled with a main() method for an entry
point- it's interpreted. When you run a python script, everything that
isn't indented is run, from top to bottom, in order. So for instance,
when the interpreter sees the line
def main() :
   pass
it creates a function called main. If you were to have the statement
x= 5
the value 5 would be assigned to x at that time. There are two ways to
execute these scripts- by running them directly and by importing them
into another module. The second way, with the main method, the script
will be run any time it is imported. The first relies on the fact that
any module run as a script has a __name__ attribute of "__main__"
(usually it's the name of the module). The first program acts more
like the C code would- the "main" part of it will only be run if that
script is executed.


> Thanks and regards,
> Tim
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From laurentluce49 at yahoo.com  Fri Jul 10 21:52:24 2009
From: laurentluce49 at yahoo.com (Laurent Luce)
Date: Fri, 10 Jul 2009 18:52:24 -0700 (PDT)
Subject: windows explorer integration
Message-ID: <44278.3184.qm@web54207.mail.re2.yahoo.com>


Hello,

Do you know if it is possible to write a plugin for windows explorer using win32 module ?

The idea is to modify the way the folders/files are displayed in the explorer window and also to provide some controls.

Laurent



From ryankaskel at gmail.com  Fri Jul 10 21:57:43 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Fri, 10 Jul 2009 18:57:43 -0700 (PDT)
Subject: Addind imports to a class namespace
Message-ID: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>

Greetings,

In order to avoid circular imports, I have a class that I want to
improve upon:

Class GenerateMenuXhtml(threading.Thread):
    """
    Subclasses a threading.Thread class to generate a menu's XHTML in
a separate
    thread. All Link objects that have this menu associated with it
are gathered
    and combined in an XHTML unordered list.

    If the sender is of type Link, then all menus associated with that
link are
    iterated through and rebuilt.
    """
    def __init__(self, instance):
        from asqcom.apps.staticpages.models import Menu, Link
        self.Link = Link
        self.Menu = Menu

As you can see I just expose these imports by attaching them to
members of the class. There must be "prettier" option though where I
can just add these imoprts to the class's namespace so all methods of
any instance will have access to the imported modules.

How would I go about doing this? How can I access the namespace of any
class? Through Class.__dict__?

Thanks,
Ryan



From greg at cosc.canterbury.ac.nz  Fri Jul 10 22:25:11 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sat, 11 Jul 2009 14:25:11 +1200
Subject: language analysis to enforce code standards
In-Reply-To: <h37mdh$rfm$1@panix3.panix.com>
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
	<pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
	<mailman.2948.1247229186.8015.python-list@python.org>
	<h37mdh$rfm$1@panix3.panix.com>
Message-ID: <7bqbeiF1rue32U1@mid.individual.net>

Aahz wrote:

> Much simpler and *way* more efficient with a set:
> 
> if len(set(s)) < N:
>     print "Must have at least %s different characters" % N

Or you could do a dictionary lookup on the words.
I can just see the error message:

   "Your comment must include at least one verb,
   one noun, one non-cliched adjective and one
   Monty Python reference."

-- 
Greg


From aahz at pythoncraft.com  Fri Jul 10 23:34:25 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 20:34:25 -0700
Subject: sys.exit() and PyRun_SimpleFileExFlags()
References: <mailman.2922.1247183197.8015.python-list@python.org>
Message-ID: <h39181$9hn$1@panix3.panix.com>

In article <mailman.2922.1247183197.8015.python-list at python.org>,
=?ISO-8859-1?Q?Xavier_B=E9nech?=  <xavier.benech at t-immersion.com> wrote:
>
>There is a behaviour I do not understand of PyRun_SimpleFileExFlags(), 
>normally when it executes a python script containing a sys.exit(), it 
>results by ending the calling application.

If nobody responds on c.l.py, I suggest trying capi-sig.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From marty.musatov at gmail.com  Fri Jul 10 23:34:25 2009
From: marty.musatov at gmail.com (Musatov)
Date: Fri, 10 Jul 2009 20:34:25 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<h38f6t01fj2@news7.newsguy.com>
Message-ID: <f7013f86-ac00-496a-b875-13d67e689e7c@t21g2000yqi.googlegroups.com>

Martin Musatov wrote:
David Bernier wrote:
> scriber77 at yahoo.com wrote:
> [...]
>
> > community. But perhaps he is trying to see things a bit differently
> > and is just not getting the feedback he needs, so he is throwing
> > tantrums apparently across USENET.
> >
> > Like I said before, I am just trying to do right by this person who
> > contacted me, and seemed to be a decent person with a genuine interest
> > in mathematics. He was very respectful.
> >
> > Alas, I am at a loss on what specific feedback to give him on his
> > paper as though I am a professor of Mathematics, Computer Science is
> > not my specialty.
> >
> > I told him I would try to get him some feedback on the equations on
> > page 3.  Would any of you be so kind to help me?
> >
> > Here is the paper: http://MeAmI.org/pversusnp.pdf
> >
> > I do thank you for your time.
> >
> > Good day,
> >
> > Professor X
>
> This is what there is at the bottom of page 3:
>
> << Conclusion: Binary revisions are allowed given the above formulas. >>
>
> So I don't understand the proposed solution for the "P = NP"
> problem.
>
> David Bernier

P can be equal to N and not P when it is in brackets vs. parantheses.
The dots ib the equation in "P = [dots] <i>N</i> (dots) <i>P</i>. The
difference between the brackets and the paranthesis represents a
margin of time in computation. The dots present in the paper (I am not
able to render them here, but they are in the .pdf file) represent a
non-deterministic symbolic means of representing language. Thank you
for your respone.

The conclusion means traditional characters and symbols are not ideal
for binary computation.


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 11 00:01:03 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 11 Jul 2009 04:01:03 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<mailman.2962.1247243254.8015.python-list@python.org>
Message-ID: <0267ffdf$0$18215$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 12:27:25 -0400, Charles Yeomans wrote:

>> (3) assert is absolutely unsuitable for enforcing pre-conditions and
>> post-
>> conditions, unless such conditions are mere "guidelines", because
>> assert
>> can be switched off at runtime.
> 
> 
> Unless, of course, you want to switch off such checking at runtime, as
> you might when using a design-by-contract approach.

So is design-by-contract just another way of saying "let's hope the data 
is valid, because if it's not, we're screwed"?

Perhaps Python should have a new statement, `assume`, used just like 
`assert` except it never actually performs the test or raises an error.


-- 
Steven


From tjreedy at udel.edu  Sat Jul 11 01:04:45 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 11 Jul 2009 01:04:45 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <0267ffdf$0$18215$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>	<pan.2009.07.10.02.28.04.344000@nowhere.com>	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>	<mailman.2962.1247243254.8015.python-list@python.org>
	<0267ffdf$0$18215$c3e8da3@news.astraweb.com>
Message-ID: <h396hc$hgp$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 12:27:25 -0400, Charles Yeomans wrote:
> 
>>> (3) assert is absolutely unsuitable for enforcing pre-conditions and
>>> post-
>>> conditions, unless such conditions are mere "guidelines", because
>>> assert
>>> can be switched off at runtime.
>>
>> Unless, of course, you want to switch off such checking at runtime, as
>> you might when using a design-by-contract approach.
> 
> So is design-by-contract just another way of saying "let's hope the data 
> is valid, because if it's not, we're screwed"?
> 
> Perhaps Python should have a new statement, `assume`, used just like 
> `assert` except it never actually performs the test or raises an error.

The manual says quite clearly

"The simple form, assert expression, is equivalent to
if __debug__:
    if not expression: raise AssertionError"

It should be used when and only when one actually wants the double 
condition check, and not as an abbreviation of the second conditional only.

tjr





From haematopus at gmail.com  Sat Jul 11 01:52:40 2009
From: haematopus at gmail.com (oystercatcher)
Date: Fri, 10 Jul 2009 22:52:40 -0700 (PDT)
Subject: fedora 3.1 python install
Message-ID: <69d90aab-eee3-4fa3-8960-4548e4e706d7@h2g2000yqg.googlegroups.com>

had installed python 3.0. on fc11 x64
the only anomalies were a couple of tests failed during the make
test.  make altinstall was fine and have been using it for a simple
math exercise.

attempting to install python 3.1 the make test hangs at
test_httpservers and I had to kill the task after waiting quite
awhile.  now probably this is no big deal and I should just go ahead
and run the make altinstall but it would be nice to know a bit more
about what is going on here.

thanks


From nobody at nowhere.com  Sat Jul 11 02:24:02 2009
From: nobody at nowhere.com (Nobody)
Date: Sat, 11 Jul 2009 07:24:02 +0100
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
Message-ID: <pan.2009.07.11.06.24.02.406000@nowhere.com>

On Fri, 10 Jul 2009 09:23:54 +0000, garabik-news-2005-05 wrote:

>>> I would like to learn a way of changing the colour of a particular
>>> part of the output text. I've tried the following
> 
>> On Unix operating systems this would be done through the curses interface:
>> 
>> http://docs.python.org/library/curses.html
> 
> Or using ANSI colour codes:
> 
> colours = {
>             'none'       :    "",
>             'default'    :    "\033[0m",
>             'bold'       :    "\033[1m",

[snip]

>             # non-standard attributes, supported by some terminals 

This comment should have appeared immediately after "none" ;)

Hard-coding control/escape sequences is just lame. Use the curses modules
to obtain the correct sequences for the terminal.



From research at johnohagan.com  Sat Jul 11 02:30:24 2009
From: research at johnohagan.com (John O'Hagan)
Date: Sat, 11 Jul 2009 06:30:24 +0000
Subject: tough-to-explain Python
In-Reply-To: <001401ca014c$ca414d60$0d00a8c0@Hendrik>
References: <h309ot$bii$1@reader1.panix.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<001401ca014c$ca414d60$0d00a8c0@Hendrik>
Message-ID: <200907110630.24557.research@johnohagan.com>

On Fri, 10 Jul 2009, Hendrik van Rooyen wrote:
> "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
> >On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:

[...]

> >> Programming is not like any other human activity.
> >
> >In practice? In principle? Programming in principle is not the same as it
> >is performed in practice.
> >
> >But in either case, programming requires both the logical reasoning of
> >mathematics and the creativity of the arts. Funnily enough,
>
> I do not buy this arty creativity stuff. - or are you talking about
> making a website look pretty?
>
> >mathematicians will tell you that mathematics requires the same, and so
> >will the best artists. I think mathematicians, engineers, artists, even
> >great chefs, will pour scorn on your claim that programming is not like
> >any other human activity.
>
> So a chef is now an authority on programming?
>
> Programming is actually kind of different - almost everything else is
> just done, at the time that you do it.
>
> Programming is creating stuff that is completely useless until it is
> fed into something that uses it, to do something else, in conjuction
> with the thing it is fed into, at a later time.
>
> This is a highly significant difference, IMHO.

[...]

The drawings produced by an architect, the script of a play, the score of a 
piece of music, and the draft of a piece of legislation are all examples of 
other things which are "useless" until they are interpreted in some way. 

There are countless human activities which require a program, i.e. a conscious 
plan or strategy, formed at least partly by a creative process, and a computer 
program is just a special case of this. 

I use Python as a tool for writing music, but I find I need both logical 
reasoning and creativity to do either. In fact, I find programming very similar 
to writing music in a rigorous contrapuntal style, where each set of choices 
constrains each other, and there is a deep aesthetic satisfaction in getting 
it right.

Regards,

John




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090711/288080b1/attachment.html>

From __peter__ at web.de  Sat Jul 11 02:51:48 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 11 Jul 2009 08:51:48 +0200
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
Message-ID: <h39cpr$o4u$01$1@news.t-online.com>

Ryan K wrote:

> In order to avoid circular imports, I have a class that I want to
> improve upon:
> 
> Class GenerateMenuXhtml(threading.Thread):
>     """
>     Subclasses a threading.Thread class to generate a menu's XHTML in
> a separate
>     thread. All Link objects that have this menu associated with it
> are gathered
>     and combined in an XHTML unordered list.
> 
>     If the sender is of type Link, then all menus associated with that
> link are
>     iterated through and rebuilt.
>     """
>     def __init__(self, instance):
>         from asqcom.apps.staticpages.models import Menu, Link
>         self.Link = Link
>         self.Menu = Menu
> 
> As you can see I just expose these imports by attaching them to
> members of the class. There must be "prettier" option though where I
> can just add these imoprts to the class's namespace so all methods of
> any instance will have access to the imported modules.
> 
> How would I go about doing this? How can I access the namespace of any
> class? Through Class.__dict__?

You can write either

class A(object):
    from some.module import Menu, Link

or 

class A(object):
    @classmethod
    do_imports(cls):
        from some.module import Menu, Link
        cls.Menu = Menu
        cls.Link = Link

A.do_imports()

to put the names into the class. The first form performs the import while 
the containing module is imported and therefore won't help with breaking 
circles. In the second form you have to defer the A.do_imports() method call 
until the import from some.module is safe.

But I still recommend that you have another look at your package 
organization to find a way to avoid circles.

Peter



From piet at cs.uu.nl  Sat Jul 11 03:54:19 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 11 Jul 2009 09:54:19 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2931.1247195266.8015.python-list@python.org>
	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
	<mailman.2983.1247257646.8015.python-list@python.org>
	<4a57aa70@news.x-privat.org>
Message-ID: <m21von8xjo.fsf@cs.uu.nl>

>>>>> I V <ivlenin at gmail.com> (IV) wrote:

>IV> On Fri, 10 Jul 2009 16:27:12 -0400, Terry Reedy wrote:
>>> a bug, bug a limitation due to using limited-range numbers. If one uses
>>> residue classes instead of integers, and makes no adjustment, I consider
>>> it wrong to blame Bentley.

>IV> But it was Bentley himself who used the C int type, so it hardly seems 
>IV> unreasonable to blame him.

If you are on a 32-bit machine, and the array to be searched contains
ints, floats or doubles, the the array must be < 2^32 bytes in size, and
as each element is at least 4 bytes, the indices are less than 2^30, so
l+u < 2^31. Therefore there is no overflow at all. I think the Bentley
programs were formulated in terms of arrays of ints. So his
implementations were safe.

If you are on a 64-bit machine you shouldn't use int for the indices
anyway (supposing int is 32 bits) but longs and then the same reasoning
shows that there are no overflows. Only when you have an array of shorts
or bytes (chars) you get the problem.

In that case the alternative formulation l + (u-l)/2 is more
robust and therefore preferable.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From Iris-und-Thomas-Lehmann at T-Online.de  Sat Jul 11 04:12:27 2009
From: Iris-und-Thomas-Lehmann at T-Online.de (Thomas Lehmann)
Date: Sat, 11 Jul 2009 01:12:27 -0700 (PDT)
Subject: Tkinter only: table widget with canvas...
References: <mailman.10638.1247239202.8014.python-list@python.org> 
	<mailman.2990.1247265085.8015.python-list@python.org>
Message-ID: <5db86de3-d0a0-42c7-8924-7ba8948cfd99@32g2000yqj.googlegroups.com>

>
> There's a working app at http://cl1p.net/tkinter_table_headers/
>
> -John

Thank you for this example. However, one issue to that...
When resizing the window (vertical) then the header moves away
from the table. How can I avoid this with the grid? With "pack"
I now this...


From p.f.moore at gmail.com  Sat Jul 11 05:25:26 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Sat, 11 Jul 2009 10:25:26 +0100
Subject: windows explorer integration
In-Reply-To: <44278.3184.qm@web54207.mail.re2.yahoo.com>
References: <44278.3184.qm@web54207.mail.re2.yahoo.com>
Message-ID: <79990c6b0907110225p14dd718bv26a36e5b13d5e51@mail.gmail.com>

2009/7/11 Laurent Luce <laurentluce49 at yahoo.com>:
> Do you know if it is possible to write a plugin for windows explorer using win32 module ?

Yes, I believe it is. There are a number of Python projects (I believe
TortoiseHg is one) that do this sort of thing.

However, I don't know anything about how to do it - you should check
MSDN, the PyWin32 samples, and maybe something like TortoiseHg, for
sample code.

Paul.


From magobin at gmail.com  Sat Jul 11 06:39:25 2009
From: magobin at gmail.com (Alex)
Date: Sat, 11 Jul 2009 03:39:25 -0700 (PDT)
Subject: problem with keys combination!
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
	<mailman.2986.1247259250.8015.python-list@python.org>
Message-ID: <dc7e6aad-f459-4760-93d0-3bb288afc5d1@a26g2000yqn.googlegroups.com>


> Blocking Ctrl-Alt-Del leaves the power switch or maybe the plug as the
> only way for the user to regain control. Why would you want to do that?

ONly for the reason that I explaine above...is for my little joke
application !
And I want disable all keys for about 30 seconds (time to erase
background)
I read about getasynckey() to intercept a key...but I don't know how
to change key pressed with another...maybe a solution ?

Alex


From gslindstrom at gmail.com  Sat Jul 11 07:10:17 2009
From: gslindstrom at gmail.com (gslindstrom)
Date: Sat, 11 Jul 2009 04:10:17 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <adbcd3fe-5468-4490-a7f1-1fdf359f0bb4@t33g2000yqe.googlegroups.com>

On Jul 10, 2:22?pm, walterbyrd <walterb... at iname.com> wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.
>
> Since backward compatibility is being thrown away anyway, why not
> enforce the four space rule?
>

There is a routine in the Scripts directory, reindent.py, that will
take your source file(s) and remove tabs, unify the indents to 4-
spaces, remove needless characters at the end of lines, etc.  IIRC, it
was written by Tim Peters.  We run all of our source files though
before checking them into svn.


--greg


From mail at microcorp.co.za  Sat Jul 11 08:01:25 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 14:01:25 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com><00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <000f01ca021f$5132b5c0$0d00a8c0@Hendrik>

"Steven D'Aprano" <steve at REMOVE-THIS-cyb.....ce.com.au> wrote:

>On Fri, 10 Jul 2009 12:54:21 +0200, Hendrik van Rooyen wrote:
>
>> "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
>> 
>>>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>>>
>>>>> persistent idea "out there" that programming is a very accessible
>>>>> skill, like cooking or gardening, anyone can do it, and even profit
>>>>> from it, monetarily or otherwise, etc., and to some extent I am
>>>> 
>>>> Programming is not like any other human activity.
>>>
>>>In practice? In principle? Programming in principle is not the same as
>>>it is performed in practice.
>>>
>>>But in either case, programming requires both the logical reasoning of
>>>mathematics and the creativity of the arts. Funnily enough,
>> 
>> I do not buy this arty creativity stuff. - or are you talking about
>> making a website look pretty?
>
>I must admit, it never crossed my mind that anyone here would claim that 
>there was no creativity involved in programming, that it was all a 
>mindless, algorithmic process capable of being done by a simple 
>mechanical device.

"Programming" is the step of going from the "design" to something
that tells the machine how to implement the design.

The creativity could, arguably, be in the "Design".
Not in the translation to python, or assembler.
No way.  That is just coding.

>
>This is certainly the accusation made against *bad* programmers -- that 
>they can't actually solve new, unique problems, but just apply recipes 
>they learned without any insight or intelligence. The sort of people who 
>program so poorly that "a trained monkey could do what they do".
>
>Do you really think that applies to good programmers too? If so, then a 
>good code generator should be able to replace any programmer. Is that 
>what you believe?
>

Should eventually be possible, with sufficient restrictions to start off.
UML wants to go this route...

But may my eyes be stopped and my bones be heaped with dust
ere I see the day...

>
 >
>>>mathematicians will tell you that mathematics requires the same, and so
>>>will the best artists. I think mathematicians, engineers, artists, even
>>>great chefs, will pour scorn on your claim that programming is not like
>>>any other human activity.
>> 
>> So a chef is now an authority on programming?
>
>Did I say that?

No.  I just read it like that to irritate you.

>
>Chefs are authorities on OTHER HUMAN ACTIVITIES.
>
>
>
>> Programming is actually kind of different - almost everything else is
>> just done, at the time that you do it.
>> 
>> Programming is creating stuff that is completely useless until it is fed
>> into something that uses it, to do something else, in conjuction with
>> the thing it is fed into, at a later time.
>
>Somebody should teach Hendrik that human beings have been creating TOOLS 
>for hundreds of thousands of years. People have been creating tools to 
>build tools for thousands of years. Software is just more of the same.

I disagree - I actually own some machine tools, so I am a little
bit acquainted with what they can do, and it is not at all like computing
at any level I can think of - they are merely extensions of the hand, making
the transformation of materials more accurate and faster.

The line only becomes blurred when a processor is added, and a STORED
PROGRAM is brought into the equation.

>
>Even *soup stock* fits the same profile as what Hendrik claims is almost 
>unique to programming. On its own, soup stock is totally useless. But you 
>make it, now, so you can you feed it into something else later on.
>
>Or instant coffee.
>
>No, Henrik, if that's the best you can do, it's not very good. It is 
>rather sad, but also hilarious, that the most different thing you have 
>noticed about software is that it's just like instant coffee.
>

You have a wonderful ability to grab hold of part of a definition
and to ignore the rest, just like I can misread what you write.

Coffee and soup stay coffee and soup on re hydration.  Mixing it
in with something else is not at all the same - it does not "DO" anything
else in conjunction with the thing it is fed into - how is that like 
programming, and executing a program?

I am sorry if you are confusing the drinking of coffee,
which is an ancilliary activity to programming, with the
actual programming itself.

>
>
>> This is a highly significant difference, IMHO.
>
>
>>>[...]
>>>> He talks about how "when all is said and done, the only thing
>>>> computers can do for us is to manipulate symbols and produce results
>>>> of such manipulations" and he emphasises the "uninterpreted" nature of
>>>> mechanical symbol manipulation, i.e. that the machine is doing it
>>>> mindlessly.
>>>
>>>"Manipulate symbols" is so abstract as to be pointless. By that
>>>reasoning, I can build a "computer" consisting of a box open at the top.
>>>I represent a symbol by an object (say, a helium-filled balloon, or a
>>>stone), instead of a pattern of bits. I manipulate the symbol by holding
>>>the object over the box and letting go. If it flies up into the sky,
>>>that represents the symbol "Love is War", if it falls into the box, it
>>>represents the symbol "Strength is Blue", and if it just floats there,
>>>it represents "Cheddar Cheese". This is a deterministic, analog computer
>>>which manipulates symbols. Great.
>>>
>>>And utterly, utterly useless. So what is my computer lacking that real
>>>computers have? When you have answered that question, you'll see why
>>>Dijkstra's claim is under-specified.
>>>
>>>
>> So if computers do not manipulate symbols, what is it that they do?
>
>Did I say they don't manipulate symbols?

No you wanted someone to tell you how to make your
box machine useful, and that was too difficult, so I went this way.

>
>
>> They
>> sure cannot think,
>> or drink,
>> or reason,
>
>They can't reason? Then what are they doing when they manipulate symbols?

They simply manipulate symbols.
They really do.
There is no reasoning involved.

Any reasoning that is done, was done in the mind of the human who designed
the system, and the the machine simply manipulates the implementation of
the abstract symbols, following the implementation of the abstract rules that
were laid down.  No reasoning at run time at all.

Lots of decision making though - and it is this ability to do this now, and
something else later, that tricks the casual observer into thinking that there
is somebody at home - a reasoning ghost in the machine.

>
>Yet again, it didn't even cross my mind that somebody would make this 
>claim. My entire point is that it's not enough to just "manipulate 
>symbols", you have to manipulate symbols the correct way, following laws 
>of logic, so that the computer can *mindlessly* reason.

No. 

There is no requirement for dragging in things like "the laws of logic"
or any arbitrarily chosen subset.  You can build a machine to do
essentially "anything" - and people like Turing and his ilk have
spent a lot of skull sweat to try to define what is "general purpose",
to enable you to do "anything"

>
>
>> or almost any verb you can think of.
>
>If you're going to take that argument, then I'll remind you that there 
>are no symbols inside a computer. There are only bits. And in fact, there 
>aren't even any bits -- there are only analog voltages, and analog 
>magnetic fields.
>

Duh - sorry to hear that - I have only been doing digital electronics
now for more years than I care to remember - but maybe there
is a difference in how you define "analogue". - maybe something like:
"if I can measure it with a multimeter, it is an analogue signal, because
a multimeter is capable of measuring analogue signals"  - a bit fallacious.

More seriously,  I again differ on the symbol bit - I am, right now, 
working on a little processor that mindlessly does I/O, by manipulating 
bits from one representation to another.  In this case, the symbols
and the bits are mostly identical - but please do not try to tell
me that there are no symbols inside the little processors' 
memory - I know they are there, because I have arranged for 
them to be put there, via an RS-232 feed.

And my stored program actually arranges for the incoming symbols
to do things like activating output relays, and changes on input lines
actually cause other symbols to be transmitted out of the RS-232
port.  The whole thing is simply rotten with symbology - in fact all
it does, is manipulating the implementation of the abstract symbols 
in my mind.
It does so mindlessly.
This specific thing is so simple, that it hardly uses the
"logical ability" of the processor.  And please remember that
for a function with two input bits and a single output bit, there can 
at most be eight possible outcomes, not all of which are useful, for
some definition of useful.  But they exist, and you can use them, if 
you want. And you do not even have to be consistent, if you do not
want to be, or if it is convenient not to be.

I think it is this horrendous freedom that Dijkstra was talking about
when he was referring to the "power beyond your wildest dreams",
or some such.

>
>> "Manipulating symbols" is actually an elegant definition. Try coming up
>> with a better one and you will see.
>
>As I said above, it's not enough to just manipulate symbols. Here's a set 
>of rules to manipulate symbols:
>
>X => 0
>
>or in English, "Any symbol becomes the zero symbol".
>
>That's symbol manipulation. Utterly useless. This is why it's not enough 
>to just manipulate symbols, you have to manipulate them THE RIGHT WAY.
>

No.
There is no RIGHT WAY.
Really.
There are only ways that are useful, or convenient.

In my little processor, I can cause any result
to occur, and the rules can be as silly as your
example - if it is useful for you, under some
circumstances, for all symbols to become the
symbol for zero, then go for it - The point is that 
there is nothing prohibiting it to be adopted as a
rule for a machine to implement.  

/dev/null anyone?

- Hendrik





From mail at microcorp.co.za  Sat Jul 11 08:14:55 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 14:14:55 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<c40ec96a-5494-483c-a461-676c8bb29876@x3g2000yqa.googlegroups.com>
Message-ID: <001001ca0221$33a04c00$0d00a8c0@Hendrik>

"pdpi" <pd....iro at gmail.com> wrote;

>I've always found cooking an apt metaphor for programming.

No this is wrong.

Writing a recipe or a cookbook is like programming.

Cooking, following a recipe, is like running a program.

- Hendrik





From jjposner at optimum.net  Sat Jul 11 09:31:58 2009
From: jjposner at optimum.net (John Posner)
Date: Sat, 11 Jul 2009 09:31:58 -0400
Subject: Tkinter only: table widget with canvas...
In-Reply-To: <mailman.54.1247306403.18041.python-list@python.org>
References: <mailman.54.1247306403.18041.python-list@python.org>
Message-ID: <4A58944E.2030009@optimum.net>


>> There's a working app at http://cl1p.net/tkinter_table_headers/
> Thank you for this example. However, one issue to that...
> When resizing the window (vertical) then the header moves away
> from the table. How can I avoid this with the grid? With "pack"
> I now this...

Oops ... packing can be tricky. Try these modifications:

   header_frm.pack(side=TOP, anchor=W, expand=False)
    ...
   table_frm.pack(side=TOP, expand=True, fill=BOTH)

You also might try constraining the top-level (root) window, using these 
methods:

  rt.geometry(XXX, YYY)
  rt.resizable(False, True)

-John





From ryankaskel at gmail.com  Sat Jul 11 09:55:34 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Sat, 11 Jul 2009 06:55:34 -0700 (PDT)
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
Message-ID: <89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>

Thanks for your help Peter.

I'm thinking that perhaps this isn't a circular import and that I
don't understand importing. Here is a better explanation of my case (I
am using Django):

I have file x.py that declares classes A, B, C.

There is also a file y.py that contains two methods T, U and the class
that we are talking about above.

x.py uses a dispatcher system to connect a signal to methods T and U
in y.py so it does: from y import T, U.

y.py needs to use classes A, B, C which is basically Menu and Link
(and some other class) above so I am thinking that if in y.py I have
from x import A, B, C that will cause a circular import?

Is this not correct and if it isn't can you explain why? Does using
from ... import X, Y, Z, i.e. explicit imports avoid this problem or
does it exacerbate it?

Thanks,
Ryan


From XX.XmcX at XX.XmclaveauX.com  Sat Jul 11 10:13:20 2009
From: XX.XmcX at XX.XmclaveauX.com (MC)
Date: Sat, 11 Jul 2009 16:13:20 +0200
Subject: windows explorer integration
References: <mailman.2998.1247277549.8015.python-list@python.org>
Message-ID: <mn.5bcd7d9798964fe2.46195@XX.XmclaveauX.com>

Hi!

Possible!  With Pywin32.
I see two ways:
  - add a "toolBar" ; see the exemple for Internet-Explorer (it run for 
both, IE & explorer)
  - add an entry in the context menu (right click)

@-salutations
--
Michel Claveau

-- 
@-salutations

Michel Claveau




From __peter__ at web.de  Sat Jul 11 10:39:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 11 Jul 2009 16:39:13 +0200
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
Message-ID: <h3a865$tij$03$1@news.t-online.com>

Ryan K wrote:

> I'm thinking that perhaps this isn't a circular import and that I
> don't understand importing. Here is a better explanation of my case (I
> am using Django):
> 
> I have file x.py that declares classes A, B, C.

Classes in Python are executable code, just like import-statements. That's 
why there is no Python equivalent to forward declarations in other 
languages; every name has to be known at the point where it occurs in the 
module.
 
> There is also a file y.py that contains two methods T, U and the class
> that we are talking about above.
> 
> x.py uses a dispatcher system to connect a signal to methods T and U
> in y.py so it does: from y import T, U.
> 
> y.py needs to use classes A, B, C which is basically Menu and Link
> (and some other class) above so I am thinking that if in y.py I have
> from x import A, B, C that will cause a circular import?

Yes. Having x import y and y import x creates a cycle. If you cannot avoid 
this by moving to a simpler design you can always introduce a third module z
that imports x and y, and then explicitly resolves the circular references.
 
> Is this not correct and if it isn't can you explain why? Does using
> from ... import X, Y, Z, i.e. explicit imports avoid this problem or
> does it exacerbate it?

It has no effect.

from module import X

is equivalent to

import module
X = module.X
del module # just the name, not the module itself

Peter



From mail at microcorp.co.za  Sat Jul 11 11:10:04 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 17:10:04 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><00720d76$0$9710$c3e8da3@news.astraweb.com><001401ca014c$ca414d60$0d00a8c0@Hendrik>
	<200907110630.24557.research@johnohagan.com>
Message-ID: <007701ca0240$77f9c2e0$0d00a8c0@Hendrik>

 John O'Hagan  wrote:


>The drawings produced by an architect, the script of a play, the score of a
piece of music, and the draft of a piece of >legislation are all examples of
other things which are "useless" until they are interpreted in some way.

Granted.
But...

>There are countless human activities which require a program, i.e. a conscious
plan or strategy, formed at least partly >by a creative process, and a computer
program is just a special case of this.

The difference is that for a piece of music, or a recipe for
"bobotie", there is room for artistry also in the performance
or preparation.

If the piece of music is reduced to a scroll with holes in it
and played on a pianola, then nobody in his right mind
would call the mechanically produced sounds
"a great performance".

And this is the essential difference that sets programming apart from
cookbook writing or drawing architectural plans - the one thing that
makes the real difference is the mindlessness of the performer.

(maybe I should conceed that writing legislation is a form of
programming, as the constabulary does not have a reputation
for anything other than a plodding consistency)

>I use Python as a tool for writing music, but I find I need both logical
reasoning and creativity to do either. In fact, I >find programming very similar
to writing music in a rigorous contrapuntal style, where each set of choices
constrains >each other, and there is a deep aesthetic satisfaction in getting it
right.

Getting it right has to do with the design, not the programming -

Have you ever struggled to get something right, and then one day
you take a different tack, and suddenly it is as if you cannot do
anything wrong - everything just falls into place? - That is the time
that you get the good feeling.

The difference between the one and the other is the difference
between bad or indifferent design and good design.  When you
have a good design, the rest follows.  If your design is crud, no
matter what you do, you struggle and nothing comes out just
right, despite heroic effort.

Now this stuff is easy to talk about, and immensely difficult to
do - it takes experience, some skill, some cunning, and a
willingness to experiment in an egoless fashion, amongst other
things.

And then the stupid compiler completely screws up your intent...
:-)

- Hendrik





From darcy at druid.net  Sat Jul 11 11:22:42 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Sat, 11 Jul 2009 11:22:42 -0400
Subject: tough-to-explain Python
In-Reply-To: <000f01ca021f$5132b5c0$0d00a8c0@Hendrik>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<000f01ca021f$5132b5c0$0d00a8c0@Hendrik>
Message-ID: <20090711112242.ec01ae8b.darcy@druid.net>

On Sat, 11 Jul 2009 14:01:25 +0200
"Hendrik van Rooyen" <mail at microcorp.co.za> wrote:
> "Programming" is the step of going from the "design" to something
> that tells the machine how to implement the design.
> 
> The creativity could, arguably, be in the "Design".
> Not in the translation to python, or assembler.
> No way.  That is just coding.

One might also argue that divorcing the design from the code is the
problem in a lot of legacy code.  See Agile Programming methods.  Now
you could say that there is a design step still in talking to the
client and making a plan in your head or in some notes but that's like
saying that Michelangelo was done creating after discussing the Sistine
Chapel with Pope Sixtus and that the rest was just a house painting job.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From mail at microcorp.co.za  Sat Jul 11 11:58:32 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 17:58:32 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com><00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org><007318de$0$9710$c3e8da3@news.astraweb.com><000f01ca021f$5132b5c0$0d00a8c0@Hendrik>
	<20090711112242.ec01ae8b.darcy@druid.net>
Message-ID: <007801ca0240$78a01500$0d00a8c0@Hendrik>

"D'Arcy J.M. Cain" <d.. at druid.net>

> One might also argue that divorcing the design from the code is the
> problem in a lot of legacy code.  See Agile Programming methods.  Now
> you could say that there is a design step still in talking to the
> client and making a plan in your head or in some notes but that's like
> saying that Michelangelo was done creating after discussing the Sistine
> Chapel with Pope Sixtus and that the rest was just a house painting job.

How do you know that it was not exactly like that - he did, after all, take
a much longer time than expected to complete the job - just like a house
painter that gets paid by the hour. :-)

It is also unreasonable to assume the opposite fallacy - that he was in
a creative frenzy from the start to the time at the end when he was
cleaning his brush after applying the last spot of paint.

But it is a valid point - it is often difficult to draw the line between the
design and the implementation - and one of the reasons that we all
like to program in python, is that it is almost a language that is a
design language that can also be run directly.  - I have lately been doing
stuff like writing rough prototypes using python syntax to serve as
designs for some of the assembler thingies I do. If you muck around
a bit at the lower level, you will also be more aware of the dichotomy
between the design and the implementation - in python, it is not obvious
at all.  In assembler, it is glaring.  But in either place, if you get it wrong,
you suffer. -  your programs cripple along, or they hardly do what
you thought they would, and they bear no relationship with what the
customer wanted.

- Hendrik





From 2.b7e15163 at googlemail.com  Sat Jul 11 13:33:10 2009
From: 2.b7e15163 at googlemail.com (Henry 'Pi' James)
Date: Sat, 11 Jul 2009 10:33:10 -0700 (PDT)
Subject: asyncore's lack of sendto(), recvfrom()
Message-ID: <3cbf56cf-1362-44af-9d9f-4f5f2f298c0a@a26g2000yqn.googlegroups.com>

Is there any good reason why sendto() and recvfrom() aren't wrapped by
asyncore? Obviously, recvfrom() cannot be replaced by recv(), but even
sendto() cannot be replace by connect() and send(), either:

I'm writing a traceroute module, and I found out that under the
current firewall configuration of my OS, sending an ICMP packet via
sendto() doesn't trigger a connection confirmation (the packet is
silently and successfully sent), while connect() does (the firewall
reports an attempted UDP connection, I'm sure why). I know Python
merely wraps send() and sendto() from <sys/socket.h> of the OS,
obviously there are some important subtle differences between the two.

Now, if I'd want to add sendto() and recvfrom() to asyncore, would it
be sufficient to simply copying its send() and recv() wrapper
functions and change the names and arguments, or are there more
modifications required?


From mondi at cs.unibo.it  Sat Jul 11 13:55:25 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Sat, 11 Jul 2009 17:55:25 +0000
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <BbWdnQyDurB8MsrXnZ2dnUVZ_j6dnZ2d@pdx.net>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
	<h37eat$qmm$1@lec.cs.unibo.it>
	<BbWdnQyDurB8MsrXnZ2dnUVZ_j6dnZ2d@pdx.net>
Message-ID: <h3ac1a$8j6$1@lec.cs.unibo.it>

Scott David Daniels wrote:
> jacopo mondi wrote:
>> Roger Binns wrote:
>>> jacopo mondi wrote:
>>>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>>>> add support to an experimental socket family.
>>> You may find it considerably easier to use ctypes since that will avoid
>>> the need for any patching.  You'll also be able to control how read and
>>> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
>>> os.fdopen to convert your raw file descriptor into a Python file object
>>> if appropriate.
> 
> The typical Python way of dealing with this is an additional module, not
> a modified module placed back in the library.  So, take the sources and
> edit, but change the module name.  Even better is figure out how to
> use _socket.pyd, to create a smaller _socketexpmodule.c and use that.
> 
> --Scott David Daniels
> Scott.Daniels at Acm.Org
Thanks a lot Scott.
If I'll write a new module, with a new name, based on socketmodule.c I
will not be able to ditribuite the source code and make users compile it
using distutils, instead I have to compile it using the whole python
build system (changing setup.py in python sources to let it know about
my new module) and distribuite the compiled .so with a script to install
it, I suppose. Anyway, that's not too bad...
Reusing _socket.so, or the main wrapper socket.pyc I think is not
possible, because I need to modify low level functions that are not exposed

thanks again
	jacopo


From davea at ieee.org  Sat Jul 11 13:56:04 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 11 Jul 2009 13:56:04 -0400
Subject: Addind imports to a class namespace
In-Reply-To: <89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
Message-ID: <4A58D234.4050607@ieee.org>

Ryan K wrote:
> Thanks for your help Peter.
>
> I'm thinking that perhaps this isn't a circular import and that I
> don't understand importing. Here is a better explanation of my case (I
> am using Django):
>
> I have file x.py that declares classes A, B, C.
>
> There is also a file y.py that contains two methods T, U and the class
> that we are talking about above.
>
> x.py uses a dispatcher system to connect a signal to methods T and U
> in y.py so it does: from y import T, U.
>
> y.py needs to use classes A, B, C which is basically Menu and Link
> (and some other class) above so I am thinking that if in y.py I have
> from x import A, B, C that will cause a circular import?
>
> Is this not correct and if it isn't can you explain why? Does using
> from ... import X, Y, Z, i.e. explicit imports avoid this problem or
> does it exacerbate it?
>
> Thanks,
> Ryan
>
>   
You indeed have described a circular import.  In this case, a mutual 
dependency exists between x.py and y.py.  This can and nearly always 
should be avoided.  That's independent of the language involved, in any 
language, circular dependencies are a code smell

Now, in Python in particular, first question is whether either x.py or 
y.py is your main script module (the one where you do the if __name__ == 
"__main__"  and the answer is yes).  If so, you're in big trouble, and 
you really need to rework it.  I could elaborate if needed, but trust 
me, you don't want to do this, even if it means writing one more module 
containing a single import line and just two or three more, and letting 
that be your script.

If that's not the case, next question is whether either module refers to 
the other one at import time, or only from inside def and class 
definitions.  If you have any top-level code going on, other than 
imports, and this code actually uses a symbol from the other module, 
you're probably in trouble.  Not as bad as first case, but still worth 
avoiding.  Sometimes this can be kludged past, by reordering things a 
little bit, maybe by moving one of the imports further down in the file.

Now back to the code smell.  If the modules really depend on each other, 
you should consider factoring out those dependencies and move them to a 
third module that both import.  Figure out why the modules are broken up 
in the particular way they are, and how you can eliminate circular 
references by refactoring.  It's hard for me to come up with general 
principles, but perhaps an example or three will help.

If a callee needs configuration information stored in globals of the 
caller, then you probably need to add that config information as parameters.

If an object needs a reference to functions in another module, add them 
when constructing the object, not statically.

Or maybe even have the one module explicitly set global variables in the 
other module, so they're in one place, instead of being only in the 
namespace of the code initializing them.

That's the best I can do without something concrete to adjust.

DaveA


From ryankaskel at gmail.com  Sat Jul 11 13:56:48 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Sat, 11 Jul 2009 10:56:48 -0700 (PDT)
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
	<h3a865$tij$03$1@news.t-online.com>
Message-ID: <b4557401-ed2f-41fa-b98c-3ab03ff47944@e18g2000vbe.googlegroups.com>

Okay so below is the acutal code. I am starting to think there is no
reason why I can't install the post_save signal in signals.py itself
and thereby avoid this issue entirely.

models.py:

class Link(CommonAbstractModel):
    ...

class Menu(CommonAbstractModel):
    ....

class StaticPage(CommonAbstractModel):
   ,,,

class CachedMenuXhtml(CommonAbstractModel):
   ...

post_save.connect(signals.build_menu, sender=Link)
post_save.connect(signals.build_menu, sender=Menu)

--------------------

# Signlas for caching of menu XHTML

class GenerateMenuXhtml(threading.Thread):

    def __init__(self, instance):
        from asqcom.apps.staticpages.models import Menu, Link,
CachedMenuXhtml
        self.Link = Link
        self.Menu = Menu
        self.CachedMenuXhtml = CachedMenuXhtml

# Function to run on post_save signal
def build_menu(sender, instance, **kwargs):
    GenerateMenuXhtml(instance).start()



From digitig at gmail.com  Sat Jul 11 14:33:19 2009
From: digitig at gmail.com (Tim Rowe)
Date: Sat, 11 Jul 2009 19:33:19 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <0267ffdf$0$18215$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com> <h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<mailman.2962.1247243254.8015.python-list@python.org>
	<0267ffdf$0$18215$c3e8da3@news.astraweb.com>
Message-ID: <aee48b3c0907111133q6194fba4qdffd7018f6794bb6@mail.gmail.com>

2009/7/11 Steven D'Aprano <steve at remove-this-cybersource.com.au>:

> So is design-by-contract just another way of saying "let's hope the data
> is valid, because if it's not, we're screwed"?

Not at all. Design By Contract is about assigning responsibility for
checking. If you don't assign responsibility then a pile of things end
up getting checked over and over again, because everybody is assuming
responsibility, and some things don't get checked at all because
everyone assumes that somebody else is checking.

In DbC, the pre-condition on data coming in to a program from outside
will usually simply be "true" -- nothing at all is assumed about it.
But when you pass it from an input conditioning routine to a
processing routine, the input conditioning routine should be able to
make guarantees about what it passes, and the processing routine
should be able to assume that those guarantees are met without having
to check it again (after all, what was the conditioning routine there
for?). Assertions might be useful in testing (because they save having
to repeat the same set of test cases on absolutely every test run) and
they're certainly useful in documenting, but if they're any use at all
in the production run-time then there's something wrong with your
development and testing processes.

-- 
Tim Rowe


From piet at cs.uu.nl  Sat Jul 11 17:21:53 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 11 Jul 2009 23:21:53 +0200
Subject: Threading.Condition problem
References: <mailman.2957.1247240742.8015.python-list@python.org>
Message-ID: <m21vom6hla.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Sorry if this appears twice, I sent it once with an attachment and it never
>GR> arrived so maybe the attachment is posing problems. I inlined the code this
>GR> time (at the bottom), thank you,

>GR> Gabriel

>GR> ########################## Original message ############################

>GR> Hello everyone,

>GR> I wrote a small example that listens for xmpp msgs in a thread. The main
>GR> program calls a function that blocks (using Condition.wait) until a msg
>GR> has been received and then returns the msg. When a msg arrives, it is
>GR> put in a variable in the thread's object, it then calls the notify()
>GR> attr on the Condition object. For some reason, this doesn't work, the
>GR> thread gets the msg, tries to notify the Condition object, fails because
>GR> the lock has not been acquired yet and blocks. I tried ignoring the
>GR> failure, thinking that since it has not been acquired yet then when it
>GR> is, it will get the msg right away and never call Condition.wait, thus
>GR> not causing any problems, but this does not work either. Does someone
>GR> know what I am doing wrong? I attached the code to this msg.

The code that puts the message in the variable should also acquire the
lock:


     def onMessage(self, conn, msg):
         with self._cv:
             self.message = msg
             self._cv.notify()

A couple of remarks:

1. I think the code is neater if all manipulation with the condition is
   done in the same class (actually in the same instance -- making this
   instance into a monitor).

class Listener(Thread):
    def __init__(self, ws):
        Thread.__init__(self)
        self.interrupt = Event()
        self.message = None
        self._cv = Condition()
        self.client = ws._client
        self.client.RegisterHandler('message', self.onMessage)
    
    def onMessage(self, conn, msg):
        with self._cv:
            self.message = msg
            try:
                self._cv.notify()
            except RuntimeError:
                print "self._cv has not acquired the lock yet"
    
    def getMsg(self):
        with self._cv:
            while !self.message
                self._cv.wait()
            return self.message

class WS(object):
    def __init__(self, username, password, res):
        self._jid = xmpp.protocol.JID(username)
        self._client = xmpp.Client(self._jid.getDomain())
#        self._cv = Condition()
    
    def getMsg(self, mid=None):
        """
        """
        return self._listener.getMsg()

Of course I haven't tested this code as I don't have the context
modules.

2. I don't know if more than one message can be delivered in the same
   instance. If yes, than your code will not work, and neither will the
   code above as, the message instance variable is never cleared. So the
   next getMsg will be happy to deliver the previous one.
   You would have to clear it when returning this one.
    
    def getMsg(self):
        with self._cv:
            while !self.message
                self._cv.wait()
            msg = self.message
            self.message = None
            return msg

3. If the messages come in faster than they can be processed some will
   be lost as they will overwrite the previous one in the self.message
   variable. The solution is to use a threading.Queue to transfer the
   messages from one thread to the other. This also saves you the hassle
   of doing your own synchronisation like above. If you are not familiar
   with synchronising multithreaded applications it is very easy to make
   errors and even if you are it is quite easy to do them wrong. I have
   been involved in distributed programming courses at university level
   and I have seen many errors in this area.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mail.to.daniel.platz at googlemail.com  Sat Jul 11 18:33:32 2009
From: mail.to.daniel.platz at googlemail.com (Daniel Platz)
Date: Sat, 11 Jul 2009 15:33:32 -0700 (PDT)
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <e038b7f1-400f-43c7-85bc-df81170353c0@r34g2000vba.googlegroups.com>

Hi,

thanks for your repleys. I have tried matplotlib but it is extremely
slow. I think it is more optimized for good looking plots instead of
speed. I do not know the Python bindings of gnuplot and Veusz. To
clarify the issue again, by 25000 data points I mean 25000 pixels,
i.e. corresponding (x,y) pairs. Thus the mapping to one pixel on the
screen is not unique.

Now, that I have to implement this problem on my own I am very
impressed by the plotting capabilities of LabView which brings thounds
of data points on screen in an extremely short time.

Thanks for your help.

Best regards,

Daniel


From ben+python at benfinney.id.au  Sat Jul 11 19:27:23 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 12 Jul 2009 09:27:23 +1000
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
	<e038b7f1-400f-43c7-85bc-df81170353c0@r34g2000vba.googlegroups.com>
Message-ID: <87vdlyls10.fsf@benfinney.id.au>

Daniel Platz <mail.to.daniel.platz at googlemail.com> writes:

> I do not know the Python bindings of gnuplot and Veusz.

A web search does, though.

    <URL:http://clusty.com/search?query=gnuplot+python>
    <URL:http://clusty.com/search?query=veusz+python>

-- 
 \        ?The problem with television is that the people must sit and |
  `\    keep their eyes glued on a screen: the average American family |
_o__)                 hasn't time for it.? ?_The New York Times_, 1939 |
Ben Finney


From ryankaskel at gmail.com  Sat Jul 11 19:43:10 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Sat, 11 Jul 2009 16:43:10 -0700 (PDT)
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
	<h3a865$tij$03$1@news.t-online.com>
	<b4557401-ed2f-41fa-b98c-3ab03ff47944@e18g2000vbe.googlegroups.com>
Message-ID: <3a6a9820-ab17-4ddc-a75b-a6b49b919af3@p15g2000vbl.googlegroups.com>

Thank you for your replies. I have factored out the dependency and
everything is solved.

Cheers,
Ryan


From ldo at geek-central.gen.new_zealand  Sat Jul 11 20:21:12 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 12 Jul 2009 12:21:12 +1200
Subject: 2.4 VS 3.1 for simple print
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
	<87hbxkm7n2.fsf@benfinney.id.au>
Message-ID: <h3ba9o$52m$3@lust.ihug.co.nz>

In message <87hbxkm7n2.fsf at benfinney.id.au>, Ben Finney wrote:

> For this and other differences introduced in the Python 3.x series, see
> <URL:http://www.python.org/dev/peps/pep-3100/>.

People never thank you for an "RTFM" response.



From ldo at geek-central.gen.new_zealand  Sat Jul 11 20:25:02 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 12 Jul 2009 12:25:02 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32eoh$ql8$1@reader1.panix.com>
	<h32fon$264$1@panix3.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com>
Message-ID: <h3bagu$52m$4@lust.ihug.co.nz>

In message <h37gv5$r81$1 at panix3.panix.com>, Aahz wrote:

> It helps to remember that names and namespaces are in many
> ways syntactic sugar for dicts or lists.

Interesting, though, that Python insists on maintaining a distinction 
between c["x"] and c.x, whereas JavaScript doesn't bother.



From greg at cosc.canterbury.ac.nz  Sat Jul 11 21:28:17 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sun, 12 Jul 2009 13:28:17 +1200
Subject: tough-to-explain Python
In-Reply-To: <mailman.3005.1247313872.8015.python-list@python.org>
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com><00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org>	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<mailman.3005.1247313872.8015.python-list@python.org>
Message-ID: <7bssfuF24o01hU1@mid.individual.net>

Hendrik van Rooyen wrote:

> The creativity could, arguably, be in the "Design".
> Not in the translation to python, or assembler.
> No way.  That is just coding.

No, the mechanical part of the process is called compiling,
and we have programs to do it for us.

By the time you've specified the design so rigorously
that not the slightest spark of creativity is needed
to implement it, you *have* coded it.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Sat Jul 11 21:34:27 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sun, 12 Jul 2009 13:34:27 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
In-Reply-To: <h3bagu$52m$4@lust.ihug.co.nz>
References: <h3291j$mfu$1@reader1.panix.com> <h32eoh$ql8$1@reader1.panix.com>
	<h32fon$264$1@panix3.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
Message-ID: <7bssrgF251u00U1@mid.individual.net>

Lawrence D'Oliveiro wrote:

> Interesting, though, that Python insists on maintaining a distinction 
> between c["x"] and c.x, whereas JavaScript doesn't bother.

And that distinction is a good thing. It means, for
example, that dictionaries can have methods without
colliding with the key space of the items put into
them.

-- 
Greg


From clp2 at rebertia.com  Sat Jul 11 21:50:28 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 11 Jul 2009 18:50:28 -0700
Subject: explode()
In-Reply-To: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
Message-ID: <50697b2c0907111850sda1fd84k65f017f2553b639a@mail.gmail.com>

On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
> ? ? ? ?What is the Python equivalent of the PHP explode() function?

some_string.split("separator")

Cheers,
Chris
-- 
http://blog.rebertia.com


From fatkinson at mishmash.com  Sat Jul 11 22:41:12 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Sat, 11 Jul 2009 19:41:12 -0700
Subject: explode()
Message-ID: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>

	What is the Python equivalent of the PHP explode() function?  





							Fred 


From sjmachin at lexicon.net  Sat Jul 11 23:01:35 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 12 Jul 2009 03:01:35 +0000 (UTC)
Subject: A zlib question
References: <80F42625-5FB2-438F-AFF2-913236A6D336@catalogix.se>
Message-ID: <loom.20090712T021938-451@post.gmane.org>

Roland Hedberg <roland <at> catalogix.se> writes:

> I have a problem with zlib and compressing/decompressing according to  
> RFC 1951.
> 
> It seems like I can decompress, something compressed according to RFC  
> 1951 by someone else, provided I set wbits to something negative (used  
> -8 but I guess any negative number would work?).

-15 will get you a 32KB window which is the best
and is the default in APIs
where a default is possible.

original_data = zlib.decompress(deflated_data, -15)

 
> But how can I compress using zlib so it doesn't add a gzip header ?

You don't need to, because zlib doesn't add a gzip header
(RFC 1952) -- it adds a zlib header (RFC 1950)
... without out any frills (i.e. default case) a zlib
stream is a 2-byte header plus the RFC 1951 deflate stream
plus a 4-byte checksum.

deflated_data = zlib.compress(uncompressed_data)[2:-4]

Coincidentally this question arose elsewhere very recently: see

http://stackoverflow.com/questions/1089662/
python-inflate-and-deflate-implementations

concatenate the above two lines -- gmane <= 80-byte line limit 8-P

BTW FWIW, one can evidently force zlib to do a gzip wrapper
instead of a zlib wrapper by setting wbits to positive > 15
[brilliant API design], but one might 
be better off using the gzip module directly ...

HTH,
John




From fatkinson at mishmash.com  Sat Jul 11 23:20:41 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Sat, 11 Jul 2009 20:20:41 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
Message-ID: <vjli55dl08g2o2otffiq25ehgl6t8v2qos@4ax.com>

On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
wrote:

>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>
>some_string.split("separator")
>
>Cheers,
>Chris

Thanks, 



						Fred 


From aahz at pythoncraft.com  Sun Jul 12 00:23:43 2009
From: aahz at pythoncraft.com (Aahz)
Date: 11 Jul 2009 21:23:43 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
Message-ID: <h3bogf$oo0$1@panix3.panix.com>

In article <h3bagu$52m$4 at lust.ihug.co.nz>,
Lawrence D'Oliveiro  <ldo at geek-central.gen.new_zealand> wrote:
>In message <h37gv5$r81$1 at panix3.panix.com>, Aahz wrote:
>>
>> It helps to remember that names and namespaces are in many
>> ways syntactic sugar for dicts or lists.
>
>Interesting, though, that Python insists on maintaining a distinction 
>between c["x"] and c.x, whereas JavaScript doesn't bother.

Why do you say "insists"?

class AttrDict:
    def __getitem__(self, key):
        return getattr(self, key)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From blepctc at free.fr  Sun Jul 12 03:47:32 2009
From: blepctc at free.fr (Baptiste Lepilleur)
Date: Sun, 12 Jul 2009 09:47:32 +0200
Subject: Looking for a tool to checkfor  python script backward compatibility
Message-ID: <4a59951a$0$10853$426a74cc@news.free.fr>

I'm looking for a tool that could be used in a pre-commit step to check that 
only features available in a "old" python version are used, say python 2.3 
for example.

Does any one know of one ? 




From vs at it.uu.se  Sun Jul 12 05:21:51 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Sun, 12 Jul 2009 11:21:51 +0200
Subject: PyODE
Message-ID: <4A59AB2F.4060708@it.uu.se>

Does anyone have PyODE running on Python 2.6.2?

--V



From ben+python at benfinney.id.au  Sun Jul 12 05:34:56 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 12 Jul 2009 19:34:56 +1000
Subject: 2.4 VS 3.1 for simple print
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
	<87hbxkm7n2.fsf@benfinney.id.au> <h3ba9o$52m$3@lust.ihug.co.nz>
Message-ID: <87r5wmkzwf.fsf@benfinney.id.au>

Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> writes:

> In message <87hbxkm7n2.fsf at benfinney.id.au>, Ben Finney wrote:
> 
> > For this and other differences introduced in the Python 3.x series, see
> > <URL:http://www.python.org/dev/peps/pep-3100/>.
> 
> People never thank you for an "RTFM" response.

It's a good thing I avoid giving such responses, then. (Pointing someone
to the specific document isn't ?RTFM?.)

-- 
 \                 ?Leave nothing to chance. Overlook nothing. Combine |
  `\          contradictory observations. Allow yourself enough time.? |
_o__)                                                     ?Hippocrates |
Ben Finney


From skip at pobox.com  Sun Jul 12 09:01:23 2009
From: skip at pobox.com (skip at pobox.com)
Date: Sun, 12 Jul 2009 08:01:23 -0500
Subject: Implementing a cache
In-Reply-To: <87ab3cwu3u.fsf@vostro.rath.org>
References: <87ab3cwu3u.fsf@vostro.rath.org>
Message-ID: <19033.56995.644542.486528@montanaro.dyndns.org>


    Nikolaus> I want to implement a caching data structure in Python that
    Nikolaus> allows me to:

    Nikolaus>  1. Quickly look up objects using a key
    Nikolaus>  2. Keep track of the order in which the objects are accessed
    Nikolaus>     (most recently and least recently accessed one, not a
    Nikolaus>     complete history)
    Nikolaus>  3. Quickly retrieve and remove the least recently accessed
    Nikolaus>     object.

My Cache module does #1 and #3.  I'm not sure if you want #2 for internal
cache maintenance or for as part of the API.

    http://www.smontanaro.net/python/Cache.py

Skip


From pdpinheiro at gmail.com  Sun Jul 12 09:27:23 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Sun, 12 Jul 2009 06:27:23 -0700 (PDT)
Subject: Implementing a cache
References: <87ab3cwu3u.fsf@vostro.rath.org>
	<mailman.3026.1247403701.8015.python-list@python.org>
Message-ID: <a9ad1d79-8308-4821-8fe8-c053b094c229@j9g2000vbp.googlegroups.com>

On Jul 12, 2:01?pm, s... at pobox.com wrote:
> ? ? Nikolaus> I want to implement a caching data structure in Python that
> ? ? Nikolaus> allows me to:
>
> ? ? Nikolaus> ?1. Quickly look up objects using a key
> ? ? Nikolaus> ?2. Keep track of the order in which the objects are accessed
> ? ? Nikolaus> ? ? (most recently and least recently accessed one, not a
> ? ? Nikolaus> ? ? complete history)
> ? ? Nikolaus> ?3. Quickly retrieve and remove the least recently accessed
> ? ? Nikolaus> ? ? object.
>
> My Cache module does #1 and #3. ?I'm not sure if you want #2 for internal
> cache maintenance or for as part of the API.
>
> ? ?http://www.smontanaro.net/python/Cache.py
>
> Skip

I'm not sure whether #2 is doable at all, as written. You _need_ a
complete history (at least the full ordering of the items in the
cache) to be able to tell what the least recently used item is.


From exarkun at divmod.com  Sun Jul 12 09:39:43 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Sun, 12 Jul 2009 09:39:43 -0400
Subject: Looking for a tool to checkfor python script backward
	compatibility
In-Reply-To: <4a59951a$0$10853$426a74cc@news.free.fr>
Message-ID: <20090712133943.2543.62461196.divmod.quotient.1539@henry.divmod.com>

On Sun, 12 Jul 2009 09:47:32 +0200, Baptiste Lepilleur <blepctc at free.fr> wrote:
>I'm looking for a tool that could be used in a pre-commit step to check that
>only features available in a "old" python version are used, say python 2.3
>for example.
>
>Does any one know of one ?
>

Run your test suite with whichever versions of Python you want to support.

Tools like Hudson (<https://hudson.dev.java.net/>) and BuildBot
(<http://buildbot.net/>) can help with this.

Jean-Paul


From stef.mientki at gmail.com  Sun Jul 12 09:40:27 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 12 Jul 2009 15:40:27 +0200
Subject: how to run the "main" section of another module ?
Message-ID: <4A59E7CB.5020908@gmail.com>

hello,

when I''m working in a library,
and want to test some of the library functions,
I need to switch to  a main application,
(which has a normal main-section)
and run that.

If the library is simply,
I add a main section to the library,
so no problem.

But if the library requires a lot of overhead,
I want to run some main program,
that has a main section,
and uses my library under construction.

So how do I call from within the library module,
in a main section in that library module,
a main in another module ?

thanks,
Stef Mientki


From skip at pobox.com  Sun Jul 12 09:40:45 2009
From: skip at pobox.com (skip at pobox.com)
Date: Sun, 12 Jul 2009 08:40:45 -0500
Subject: Implementing a cache
In-Reply-To: <a9ad1d79-8308-4821-8fe8-c053b094c229@j9g2000vbp.googlegroups.com>
References: <87ab3cwu3u.fsf@vostro.rath.org>
	<mailman.3026.1247403701.8015.python-list@python.org>
	<a9ad1d79-8308-4821-8fe8-c053b094c229@j9g2000vbp.googlegroups.com>
Message-ID: <19033.59357.223527.248051@montanaro.dyndns.org>


    >> My Cache module does #1 and #3. ?I'm not sure if you want #2 for
    >> internal cache maintenance or for as part of the API.
    >> 
    >> ? ?http://www.smontanaro.net/python/Cache.py

    pdpi> I'm not sure whether #2 is doable at all, as written. You _need_ a
    pdpi> complete history (at least the full ordering of the items in the
    pdpi> cache) to be able to tell what the least recently used item is.

I should have added that my Cache module does maintain a history.  (Clearly
it needs that to determine the LRU item.)  It is exposed as part of the API
via the ftimes method.

S


From stef.mientki at gmail.com  Sun Jul 12 09:47:27 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 12 Jul 2009 15:47:27 +0200
Subject: how to run the "main" section of another module ?
In-Reply-To: <4A59E7CB.5020908@gmail.com>
References: <4A59E7CB.5020908@gmail.com>
Message-ID: <4A59E96F.6080709@gmail.com>

Stef Mientki wrote:
> hello,
>
> when I''m working in a library,
> and want to test some of the library functions,
> I need to switch to  a main application,
> (which has a normal main-section)
> and run that.
>
> If the library is simply,
> I add a main section to the library,
> so no problem.
>
> But if the library requires a lot of overhead,
> I want to run some main program,
> that has a main section,
> and uses my library under construction.
>
> So how do I call from within the library module,
> in a main section in that library module,
> a main in another module ?
>
> thanks,
> Stef Mientki

btw,
I just found this in one of my programs (which works but isn't very 
beautiful)

In the library fill under construction I put this main section:
(sb_test.py is the main program, that has a main section and uses the 
library under construction)

if __name__ == '__main__':
    import db_test
    new_globals = {}
    new_globals [ '__name__' ] = '__main__'
    new_globals [ '__file__' ] = 'not really valuable'
    execfile ( 'db_test.py', new_globals )
 



From aahz at pythoncraft.com  Sun Jul 12 10:21:55 2009
From: aahz at pythoncraft.com (Aahz)
Date: 12 Jul 2009 07:21:55 -0700
Subject: how to run the "main" section of another module ?
References: <mailman.3028.1247406021.8015.python-list@python.org>
Message-ID: <h3cri3$171$1@panix3.panix.com>

In article <mailman.3028.1247406021.8015.python-list at python.org>,
Stef Mientki  <stef.mientki at gmail.com> wrote:
>
>when I''m working in a library, and want to test some of the library
>functions, I need to switch to a main application, (which has a normal
>main-section) and run that.

if __name__ == '__main__':
    main()

Then you can call main() from another module for testing purposes.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From piet at cs.uu.nl  Sun Jul 12 11:54:30 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 12 Jul 2009 17:54:30 +0200
Subject: how to run the "main" section of another module ?
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
Message-ID: <m2fxd1522x.fsf@cs.uu.nl>

>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:

>SM> Stef Mientki wrote:
>>> hello,
>>> 
>>> when I''m working in a library,
>>> and want to test some of the library functions,
>>> I need to switch to  a main application,
>>> (which has a normal main-section)
>>> and run that.
>>> 
>>> If the library is simply,
>>> I add a main section to the library,
>>> so no problem.
>>> 
>>> But if the library requires a lot of overhead,
>>> I want to run some main program,
>>> that has a main section,
>>> and uses my library under construction.
>>> 
>>> So how do I call from within the library module,
>>> in a main section in that library module,
>>> a main in another module ?
>>> 
>>> thanks,
>>> Stef Mientki

>SM> btw,
>SM> I just found this in one of my programs (which works but isn't very
>SM> beautiful)

>SM> In the library fill under construction I put this main section:
>SM> (sb_test.py is the main program, that has a main section and uses the
>SM> library under construction)

>SM> if __name__ == '__main__':
>SM>    import db_test
>SM>    new_globals = {}
>SM>    new_globals [ '__name__' ] = '__main__'
>SM>    new_globals [ '__file__' ] = 'not really valuable'
>SM>    execfile ( 'db_test.py', new_globals )

Why not:

import db_test
db_test.main()

I think that is what Aahz meant.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From bjorn.m.meyer at gmail.com  Sun Jul 12 13:16:13 2009
From: bjorn.m.meyer at gmail.com (Bjorn Meyer)
Date: Sun, 12 Jul 2009 11:16:13 -0600
Subject: multiprocessing and dictionaries
Message-ID: <200907121116.13828.bjorn.m.meyer@gmail.com>

I am trying to convert a piece of code that I am using the thread module with 
to the multiprocessing module.

The way that I have it set up is a chunk of code reads a text file and assigns 
a dictionary key multiple values from the text file. I am using locks to write 
the values to the dictionary.
The way that the values are written is as follows:
	mydict.setdefault(key, []).append(value)

The problem that I have run into is that using multiprocessing, the key gets 
set, but the values don't get appended.
I've even tried the Manager().dict() option, but it doesn't seem to work.

Is this not supported at this time or am I missing something?

Thanks in advance.

Bjorn


From stef.mientki at gmail.com  Sun Jul 12 14:13:53 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 12 Jul 2009 20:13:53 +0200
Subject: how to run the "main" section of another module ?
In-Reply-To: <m2fxd1522x.fsf@cs.uu.nl>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl>
Message-ID: <4A5A27E1.1090502@gmail.com>


>> SM> if __name__ == '__main__':
>> SM>    import db_test
>> SM>    new_globals = {}
>> SM>    new_globals [ '__name__' ] = '__main__'
>> SM>    new_globals [ '__file__' ] = 'not really valuable'
>> SM>    execfile ( 'db_test.py', new_globals )
>>     
>
> Why not:
>
> import db_test
> db_test.main()
>
> I think that is what Aahz meant.
>
>   
Yes I tried that too,
but it gives the following error:
"module object not callable"


db_text.__main__()
gives error:
'module' object has no attribute '__main__'

cheers,
Stef



From aahz at pythoncraft.com  Sun Jul 12 14:44:10 2009
From: aahz at pythoncraft.com (Aahz)
Date: 12 Jul 2009 11:44:10 -0700
Subject: how to run the "main" section of another module ?
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl>
	<mailman.3032.1247422431.8015.python-list@python.org>
Message-ID: <h3datq$k83$1@panix3.panix.com>

In article <mailman.3032.1247422431.8015.python-list at python.org>,
Stef Mientki  <stef.mientki at gmail.com> wrote:
>Stef deleted an attribution:
>>
>> Why not:
>>
>> import db_test
>> db_test.main()
>   
>Yes I tried that too, but it gives the following error: "module object
>not callable"

You need to create a main() function in db_test first.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From emile at fenx.com  Sun Jul 12 14:48:25 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 12 Jul 2009 11:48:25 -0700
Subject: how to run the "main" section of another module ?
In-Reply-To: <4A5A27E1.1090502@gmail.com>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>
	<4A5A27E1.1090502@gmail.com>
Message-ID: <h3db5t$9r9$1@ger.gmane.org>

On 7/12/2009 11:13 AM Stef Mientki said...
> 
>>> SM> if __name__ == '__main__':
>>> SM>    import db_test
>>> SM>    new_globals = {}
>>> SM>    new_globals [ '__name__' ] = '__main__'
>>> SM>    new_globals [ '__file__' ] = 'not really valuable'
>>> SM>    execfile ( 'db_test.py', new_globals )
>>>     
>>
>> Why not:

implied here is that you restructure...

>>
>> import db_test
>> db_test.main()
>>
>> I think that is what Aahz meant.
>>
>>   
> Yes I tried that too,
> but it gives the following error:
> "module object not callable"
> 
> 
> db_text.__main__()
> gives error:
> 'module' object has no attribute '__main__'
> 

You see, we're further assuming you've structured the module for this 
purpose.  IOW, your module should end with:

if __name__ == '__main__':
     main()

and nothing more.  Then, you can do:

import db_test
db_test.main()

Emile



From cameron.pulsford at gmail.com  Sun Jul 12 15:11:55 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Sun, 12 Jul 2009 15:11:55 -0400
Subject: Question about generators
In-Reply-To: <h3db5t$9r9$1@ger.gmane.org>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>
	<4A5A27E1.1090502@gmail.com> <h3db5t$9r9$1@ger.gmane.org>
Message-ID: <7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>

Hey everyone, I have this small piece of code that simply finds the  
factors of a number.

import sys

def factor(n):
     primes = (6*i+j for i in xrange(1, n) for j in [1, 5] if (i+j)%5 ! 
= 0)

     factors = []

     for i in [2, 3, 5]:
         while n % i == 0:
             n /= i
             factors.append(i)
     for i in primes:
         while n % i == 0:
             n /= i
             factors.append(i)
     print factors

factor(int(sys.argv[1]))

My question is, is it possible to combine those two loops? The primes  
generator I wrote finds all primes up to n, except for 2, 3 and 5, so  
I must check those explicitly. Is there anyway to concatenate the hard  
coded list of [2,3,5] and the generator I wrote so that I don't need  
two for loops that do the same thing?

I tried writing a primes function using yield statements, but it  
didn't work like I thought it would.


From alan.kesselmann at gmail.com  Sun Jul 12 15:16:29 2009
From: alan.kesselmann at gmail.com (zayatzz)
Date: Sun, 12 Jul 2009 12:16:29 -0700 (PDT)
Subject: Sockets and threading
Message-ID: <0b77e7b9-85cd-4a23-b975-5cb8ac59fe7e@j19g2000vbp.googlegroups.com>

Im trying to get aquinted to python on bit more basic level and am
following socket and threading programming tutorials from these 2
addresses :

http://heather.cs.ucdavis.edu/~matloff/Python/PyNet.pdf
http://heather.cs.ucdavis.edu/~matloff/Python/PyThreads.pdf

in this PyThreads file he sets up threaded server app which listens to
what clients send to it and echos it back to clients while adding sent
info into one string.

The problem is that the code does not work for me.

class srvr(threading.Thread):
	v = ""
	vlock = threading.Lock()
	id = 0
	def __init__(self,clntsock):
		threading.Thread.__init__(self)
		self.myid = srvr.id
		srvr.id += 1
		self.myclntsock = clntsock
	def run(self):
		while 1:
			k = self.myclntsock.recv(1)
			if k == "": break
			srvr.vlock.acquire()
			srvr.v += k
			srvr.vlock.release()
			self.myclntsock.send(srvr.v)
			self.myclntsock.close()

Instead of sendint back i get this error :
  File "server3.py", line 31, in serveclient
    k = self.myclntsock.recv(1)
  File "/usr/lib/python2.6/socket.py", line 165, in _dummy
    raise error(EBADF, 'Bad file descriptor')
socket.error: [Errno 9] Bad file descriptor

As much as i understand this line 31 is supposed to recieve stuff from
clients and has buffer size 1. I dont understand what this has to do
with file descriptor.. whatever that is anyway.

Alan


From vodkalove at gmail.com  Sun Jul 12 15:18:04 2009
From: vodkalove at gmail.com (Riley Crane)
Date: Sun, 12 Jul 2009 12:18:04 -0700 (PDT)
Subject: MySQLdb + SSH Tunnel
Message-ID: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>

OVERVIEW:
I am running a script on one machine that connects to a MySQL database
on another machine that is outside of our university's domain.
According to the administrator, network policies do not allow the
compute nodes to access machines outside of our university's domain.

COMPUTERS:
A = compute node within university (I do not have shell access)
B = 2nd machine within university that does not block outside
connections (I have root access)
C = machine outside of university (I have root access)
mysqldb on A cannot connect to C ....but.....
mysqldb on A can connect to B

WHAT I WOULD LIKE TO DO:
Is it possible to set something up where A talks to a port on B, and
that port is actually nothing more than 3306 on C?  Can I do this with
an SSH tunnel?

Can anyone please give precise instructions?


From emile at fenx.com  Sun Jul 12 15:41:31 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 12 Jul 2009 12:41:31 -0700
Subject: MySQLdb + SSH Tunnel
In-Reply-To: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
Message-ID: <h3de9f$hgf$1@ger.gmane.org>

On 7/12/2009 12:18 PM Riley Crane said...
> OVERVIEW:
> I am running a script on one machine that connects to a MySQL database
> on another machine that is outside of our university's domain.
> According to the administrator, network policies do not allow the
> compute nodes to access machines outside of our university's domain.
> 
> COMPUTERS:
> A = compute node within university (I do not have shell access)
> B = 2nd machine within university that does not block outside
> connections (I have root access)

...so B can talk to C presumably...

> C = machine outside of university (I have root access)
> mysqldb on A cannot connect to C ....but.....
> mysqldb on A can connect to B



> 
> WHAT I WOULD LIKE TO DO:
> Is it possible to set something up where A talks to a port on B, and
> that port is actually nothing more than 3306 on C?  Can I do this with
> an SSH tunnel?
> 
> Can anyone please give precise instructions?

ssh with something like...

ssh -lroot -L3306:C:3306 B

Watch out for other instances of mysql on A or B...

Emile




From mensanator at aol.com  Sun Jul 12 15:47:46 2009
From: mensanator at aol.com (Mensanator)
Date: Sun, 12 Jul 2009 12:47:46 -0700 (PDT)
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org> 
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org> 
	<mailman.3034.1247426204.8015.python-list@python.org>
Message-ID: <173f9127-2846-46a4-8392-6a7f03fde6e1@j19g2000vbp.googlegroups.com>

On Jul 12, 2:11?pm, Cameron Pulsford <cameron.pulsf... at gmail.com>
wrote:
> Hey everyone, I have this small piece of code that simply finds the ?
> factors of a number.
>
> import sys
>
> def factor(n):
> ? ? ?primes = (6*i+j for i in xrange(1, n) for j in [1, 5] if (i+j)%5 !
> = 0)
>
> ? ? ?factors = []
>
> ? ? ?for i in [2, 3, 5]:
> ? ? ? ? ?while n % i == 0:
> ? ? ? ? ? ? ?n /= i
> ? ? ? ? ? ? ?factors.append(i)
> ? ? ?for i in primes:
> ? ? ? ? ?while n % i == 0:
> ? ? ? ? ? ? ?n /= i
> ? ? ? ? ? ? ?factors.append(i)
> ? ? ?print factors
>
> factor(int(sys.argv[1]))
>
> My question is, is it possible to combine those two loops?

Yeah, get rid of the first loop.

> The primes ?
> generator I wrote finds all primes up to n, except for 2, 3 and 5, so ?
> I must check those explicitly. Is there anyway to concatenate the hard ?
> coded list of [2,3,5] and the generator I wrote so that I don't need ?
> two for loops that do the same thing?

primes.extend([2,3,5])

>
> I tried writing a primes function using yield statements, but it ?
> didn't work like I thought it would.



From vilya.harvey at gmail.com  Sun Jul 12 15:55:49 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sun, 12 Jul 2009 20:55:49 +0100
Subject: Question about generators
In-Reply-To: <7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
Message-ID: <6aef848f0907121255n7d5cff37r6b01828cfb0ba6db@mail.gmail.com>

2009/7/12 Cameron Pulsford <cameron.pulsford at gmail.com>:
> My question is, is it possible to combine those two loops? The primes
> generator I wrote finds all primes up to n, except for 2, 3 and 5, so I must
> check those explicitly. Is there anyway to concatenate the hard coded list
> of [2,3,5] and the generator I wrote so that I don't need two for loops that
> do the same thing?

itertools.chain([2, 3, 5], primes) is what you're looking for, I think.

Vil.


From rhodri at wildebst.demon.co.uk  Sun Jul 12 16:13:58 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 12 Jul 2009 21:13:58 +0100
Subject: need to write a assembly progrm
In-Reply-To: <h393ob$d8u$2@ger.gmane.org>
References: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
	<op.uwup5bama8ncjz@gnudebst> <h393ob$d8u$2@ger.gmane.org>
Message-ID: <op.uwy05kura8ncjz@gnudebst>

On Sat, 11 Jul 2009 05:17:18 +0100, Dennis Lee Bieber  
<wlfraed at ix.netcom.com> wrote:

> On Fri, 10 Jul 2009 13:25:49 +0100, "Rhodri James"
> <rhodri at wildebst.demon.co.uk> declaimed the following in
> gmane.comp.python.general:
>
>> On Thu, 09 Jul 2009 11:52:44 +0100, m.reddy prasad reddy
>> <reddy.mrp at gmail.com> wrote:
>>
>> > my aim is to run the assembly programs in python.by that we can use  
>> that
>> > in
>> > the any labs.because we can run the python in the mobiles also.if we
>> > write
>> > assembly programs in the mobile ,the mobile act as a tool kit for the
>> > lab.tell me any other solutions for this
>>
>> Please define what you mean by "assembly".
>>
> 	The poorly punctuated paragraph sounds, to me, as if they mean they
> want (Windows assumed) EXE files that can be dropped onto remote/laptop
> machines without performing a full installation of Python...
>
> 	But yes... "assembly programs" does, to me, also mean things
> containing mnemonics for machine level opcodes.

Given that to me, "assembly programs" does not mean .EXE files at all,
not even a little bit, I'm prefering to refuse to guess :-)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Sun Jul 12 17:02:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 12 Jul 2009 23:02:46 +0200
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<mailman.3034.1247426204.8015.python-list@python.org>
Message-ID: <m28wit4nt5.fsf@cs.uu.nl>

>>>>> Cameron Pulsford <cameron.pulsford at gmail.com> (CP) wrote:

>CP> Hey everyone, I have this small piece of code that simply finds the
>CP> factors of a number.

Others have already given you advice to add the [2, 3, 5] to the
iterator (of which the primes.extend([2,3,5]) will not work). Please
allow me to make some other remarks.

>CP> import sys

>CP> def factor(n):
>CP>     primes = (6*i+j for i in xrange(1, n) for j in [1, 5] if (i+j)%5 ! = 0)

It is a bit misleading to call this `primes' as it will also contain
non-primes. Of course they don't harm as they will never be considered a
factor because all their prime factors will have been successfully
removed before this non prime will be considered.

>CP>     factors = []

>CP>     for i in [2, 3, 5]:
>CP>         while n % i == 0:
>CP>             n /= i
>CP>             factors.append(i)
>CP>     for i in primes:
>CP>         while n % i == 0:
>CP>             n /= i
>CP>             factors.append(i)

         You can stop the loop when n == 1. Like:
                 if n == 1: break

>CP>     print factors

>CP> factor(int(sys.argv[1]))

>CP> My question is, is it possible to combine those two loops? The primes
>CP> generator I wrote finds all primes up to n, except for 2, 3 and 5, so  I
>CP> must check those explicitly. Is there anyway to concatenate the hard  coded
>CP> list of [2,3,5] and the generator I wrote so that I don't need  two for
>CP> loops that do the same thing?

>CP> I tried writing a primes function using yield statements, but it  didn't
>CP> work like I thought it would.

See the recent thread `Why is my code faster with append() in a loop than with a large list?'
http://mail.python.org/pipermail/python-list/2009-July/718931.html
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From gagsl-py2 at yahoo.com.ar  Sun Jul 12 17:34:41 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 12 Jul 2009 18:34:41 -0300
Subject: Sockets and threading
References: <0b77e7b9-85cd-4a23-b975-5cb8ac59fe7e@j19g2000vbp.googlegroups.com>
Message-ID: <op.uwy4g9oqx6zn5v@gabriel.sleipnir-bsas>

En Sun, 12 Jul 2009 16:16:29 -0300, zayatzz <alan.kesselmann at gmail.com>
escribi?:

> 		while 1:
> 			k = self.myclntsock.recv(1)
> 			if k == "": break
> 			srvr.vlock.acquire()
> 			srvr.v += k
> 			srvr.vlock.release()
> 			self.myclntsock.send(srvr.v)
> 			self.myclntsock.close()
>
> Instead of sendint back i get this error :
>   File "server3.py", line 31, in serveclient
>     k = self.myclntsock.recv(1)
>   File "/usr/lib/python2.6/socket.py", line 165, in _dummy
>     raise error(EBADF, 'Bad file descriptor')
> socket.error: [Errno 9] Bad file descriptor
>
> As much as i understand this line 31 is supposed to recieve stuff from
> clients and has buffer size 1. I dont understand what this has to do
> with file descriptor.. whatever that is anyway.

That means the clntsock variable isn't an open, available socket. Note
that you close the socket right after sending the response - are you sure
you don't have an indentation error there?

-- 
Gabriel Genellina



From Samnsparky at gmail.com  Sun Jul 12 17:50:01 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 14:50:01 -0700 (PDT)
Subject: Webcam + GStreamer
Message-ID: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>

Hello! I need to stream from a webcam in Linux and I need to be able
to analyze the video feed frame by frame with PIL. Currently my web-
cam (Quickcam Chat) only seems to work with GStreamer so a solution
using pygst would be preferred.

Thanks for your help,
Sam


From piet at cs.uu.nl  Sun Jul 12 17:52:50 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 12 Jul 2009 23:52:50 +0200
Subject: Sockets and threading
References: <0b77e7b9-85cd-4a23-b975-5cb8ac59fe7e@j19g2000vbp.googlegroups.com>
Message-ID: <m24oth4lhp.fsf@cs.uu.nl>

>>>>> zayatzz <alan.kesselmann at gmail.com> (z) wrote:

>z> Im trying to get aquinted to python on bit more basic level and am
>z> following socket and threading programming tutorials from these 2
>z> addresses :

>z> http://heather.cs.ucdavis.edu/~matloff/Python/PyNet.pdf
>z> http://heather.cs.ucdavis.edu/~matloff/Python/PyThreads.pdf

>z> in this PyThreads file he sets up threaded server app which listens to
>z> what clients send to it and echos it back to clients while adding sent
>z> info into one string.

>z> The problem is that the code does not work for me.

>z> class srvr(threading.Thread):
>z> 	v = ""
>z> 	vlock = threading.Lock()
>z> 	id = 0
>z> 	def __init__(self,clntsock):
>z> 		threading.Thread.__init__(self)
>z> 		self.myid = srvr.id
>z> 		srvr.id += 1
>z> 		self.myclntsock = clntsock
>z> 	def run(self):
>z> 		while 1:
>z> 			k = self.myclntsock.recv(1)
>z> 			if k == "": break
>z> 			srvr.vlock.acquire()
>z> 			srvr.v += k
>z> 			srvr.vlock.release()
>z> 			self.myclntsock.send(srvr.v)
>z> 			self.myclntsock.close()


The last line is wrongly indented. It should be outside the loop. Shift
it left so that it lines up with the while. 

What happens now is that the socket is closed after the first recv().
Then the next round in the loop fails because the myclntsock is closed.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From Samnsparky at gmail.com  Sun Jul 12 17:54:13 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 14:54:13 -0700 (PDT)
Subject: Webcam + GStreamer
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
Message-ID: <1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>

On Jul 12, 3:50?pm, Sparky <Samnspa... at gmail.com> wrote:
> Hello! I need to stream from a webcam in Linux and I need to be able
> to analyze the video feed frame by frame with PIL. Currently my web-
> cam (Quickcam Chat) only seems to work with GStreamer so a solution
> using pygst would be preferred.
>
> Thanks for your help,
> Sam

Sorry, to clarify I am just having a hard time capturing frames in a
way that I can access with PIL.


From davoodvahdati2009 at gmail.com  Sun Jul 12 18:24:57 2009
From: davoodvahdati2009 at gmail.com (Davood Vahdati)
Date: Sun, 12 Jul 2009 15:24:57 -0700 (PDT)
Subject: c++ Source Code for acm 2004-2005 problems
Message-ID: <03d25e16-97d2-4b09-8113-5011c0e0ded9@p28g2000vbn.googlegroups.com>

Dear Sirs And Madams :

it is an Acm programming competition Questions in year 2004-2005 .
could you please solve problems is question ? I  Wan't C++ Source Code
program About this questions OR Problems . thank you for your prompt
attention to this matter

your faithfully.
-----------------------------------------
29th ACM International Collegiate
Sponsored by
Programming Contest, 2004-2005
Sharif Preliminary Contest
Sharif University of Technology, 28 Oct. 2004

Problem B
(Program filename: B.CPP, B.DPR, B.PAS or B.java)

Parallelogram Counting
There are n distinct points in the plane, given by their integer
coordinates. Find the number of parallelograms whose
vertices lie on these points. In other words, find the number of 4-
element subsets of these points that can be written as
{A, B, C, D} such that AB || CD, and BC || AD. No four points are in a
straight line.
Input (filename: B.IN)
The first line of the input file contains a single integer t (1 ? t ?
10), the number of test cases. It is followed by the input

data for each test case.
The first line of each test case contains an integer n (1 ? n ? 1000).
Each of the next n lines, contains 2 space-separated
integers x and y (the coordinates of a point) with magnitude (absolute
value) of no more than 1000000000.

Output (Standard Output)
Output should contain t lines.
Line i contains an integer showing the number of the parallelograms as
described above for test case i.

Sample Input
2
6
0 0
2 0
4 0
1 1
3 1
5 1
7
-2 -1
8 9
5 7
1 1
4 8
2 0
9 8

Sample Output
5
6
----------------------------------------------------------------------------------------------------------------------
Problem B-Page 1 of 1

28th ACM International Collegiate
Sponsored by
Programming Contest, 2003-2004
Sharif Preliminary Contest
Sharif University of Technology, 14 Nov. 2003

Problem C
(Program filename: C.CPP or C.PAS or C.DPR or C.java)

Toy Storage
Mom and dad have a problem: their child, Reza, never puts his toys
away when he is finished playing with them.
They gave Reza a rectangular box to put his toys in. Unfortunately,
Reza is rebellious and obeys his parents by simply
throwing his toys into the box. All the toys get mixed up, and it is
impossible for Reza to find his favorite toys anymore.
Reza's parents came up with the following idea. They put cardboard
partitions into the box. Even if Reza keeps
throwing his toys into the box, at least toys that get thrown into
different partitions stay separate. The box looks like this
from the top:

We want for each positive integer t, such that there exists a
partition with t toys, determine how many partitions
have t, toys.
Input (filename: C.IN)
The input consists of a number of cases. The first line consists of
six integers n, m, x1, y1, x2, y2. The number of
cardboards to form the partitions is n (0< n ? 1000) and the number of
toys is given in m (0<m ? 1000). The
coordinates of the upper-left corner and the lower-right corner of the
box are (x1, y1) and (x2, y2), respectively. The
following n lines each consists of two integers Ui Li, indicating that
the ends of the ith cardboard is at the coordinates
(Ui, y1) and (Li, y2). You may assume that the cardboards do not
intersect with each other. The next m lines each consists
of two integers Xi Yi specifying where the ith toy has landed in the
box. You may assume that no toy will land on a
cardboard.
A line consisting of a single 0 terminates the input.
Output (filename: C.OUT)
For each box, first provide a header stating ?Box?
on a line of its own. After that, there will be one line of output
per
count (t> 0) of toys in a partition. The value t will be followed by a
colon and a space, followed the number of
partitions containing t toys. Output will be sorted in ascending order
of t for each box.
Sample Input
4 10 0 10 100 0
20 20
80 80
60 60
40 40
5 10
15 10
95 10
25 10
65 10
75 10
35 10
45 10
55 10
85 10
5 6 0 10 60 0

4 3
15 30
3 1
6 8
10 10
2 1
2 8
1 5
5 5
40 10
7 9
0

Sample Output
Box

2: 5
Box
1: 4
2: 1
----------------------------------------------------------------------
29th ACM International Collegiate
Sponsored by
Programming Contest, 2004-2005
Sharif Preliminary Contest
Sharif University of Technology, 28 Oct. 2004

Problem D
(Program filename: D.CPP, D.DPR, or D.java)

Software Company
A software developing company has been assigned two programming
projects. As
both projects are within the same contract, both must be handed in at
the same
time. It does not help if one is finished earlier.

This company has n employees to do the jobs. To manage the two
projects more
easily, each is divided into m independent subprojects. Only one
employee can
work on a single subproject at one time, but it is possible for two
employees to
work on different subprojects of the same project simultaneously.

Our goal is to finish the projects as soon as possible.

Input (filename: D.IN)
The first line of the input file contains a single integer t (1 ? t ?
11), the
number of test cases, followed by the input data for each test case.
The first
line of each test case contains two integers n (1 ? n ? 100), and m (1
? m ?
100). The input for this test case will be followed by n lines. Each
line
contains two integers which specify how much time in seconds it will
take for
the specified employee to complete one subproject of each project. So
if the
line contains x and y, it means that it takes the employee x seconds
to complete
a subproject from the first project, and y seconds to complete a
subproject from
the second project.
Output (Standard Output)
There should be one line per test case containing the minimum amount
of time in
seconds after which both projects can be completed.

Sample Input
1
3 20
1 1
2 4
1 6

Sample Output
18

Problem D -Page 1 of 1

29th ACM International Collegiate
Sponsored by
Programming Contest, 2004-2005
Sharif Preliminary Contest
Sharif University of Technology, 28 Oct. 2004
----------------------------------------------------------------------
Problem F
(Program filename: F.CPP, F.DPR, or F.java)

Median Weight Bead
There are N beads which of the same shape and size, but with different
weights.
N is an odd number and the beads are labeled as 1, 2, ..., N. Your
task is to
find the bead whose weight is median (the ((N+1)/2)th among all
beads). The
following comparison has been performed on some pairs of beads:
A scale is given to compare the weights of beads. We can determine
which one is
heavier than the other between two beads. As the result, we now know
that some
beads are heavier than others. We are going to remove some beads which
cannot
have the medium weight.

For example, the following results show which bead is heavier after M
comparisons where M=4 and N=5.

1. Bead 2 is heavier than Bead 1.
2. Bead 4 is heavier than Bead 3.
3. Bead 5 is heavier than Bead 1.
4. Bead 4 is heavier than Bead 2.
>From the above results, though we cannot determine exactly which is
the median
bead, we know that Bead 1 and Bead 4 can never have the median weight:
Beads 2,
4, 5 are heavier than Bead 1, and Beads 1, 2, 3 are lighter than Bead
4.
Therefore, we can remove these two beads.
Write a program to count the number of beads which cannot have the
median
weight.

Input (filename: F.IN)
The first line of the input file contains a single integer t (1 ? t ?
11), the
number of test cases, followed by the input data for each test case.
The input
for each test case will be as follows:
The first line of input data contains an integer N (1=N=99) denoting
the number
of beads, and M denoting the number of pairs of beads compared. In
each of the
next M lines, two numbers are given where the first bead is heavier
than the
second bead.
Output (Standard Output)
There should be one line per test case. Print the number of beads
which can
never have the medium weight.

Sample Input Sample Output
1 2
5 4
2 1
4 3
5 1
4 2
Problem F -Page 1 of 2


From david at pythontoo.com  Sun Jul 12 18:30:12 2009
From: david at pythontoo.com (David)
Date: Sun, 12 Jul 2009 18:30:12 -0400
Subject: Webcam + GStreamer
In-Reply-To: <1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>
Message-ID: <4A5A63F4.6010301@pythontoo.com>

Sparky wrote:
> On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
>> Hello! I need to stream from a webcam in Linux and I need to be able
>> to analyze the video feed frame by frame with PIL. Currently my web-
>> cam (Quickcam Chat) only seems to work with GStreamer so a solution
>> using pygst would be preferred.
>>
>> Thanks for your help,
>> Sam
> 
> Sorry, to clarify I am just having a hard time capturing frames in a
> way that I can access with PIL.

Most web cams produce jpeg images so read the note at the bottom here;
http://effbot.org/imagingbook/format-jpeg.htm
What exactly are you trying to do? What have you tried so far and what 
happened may help.

-- 
Powered by Gentoo GNU/Linux
http://linuxcrazy.com


From ptmcg at austin.rr.com  Sun Jul 12 18:46:05 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Sun, 12 Jul 2009 15:46:05 -0700 (PDT)
Subject: c++ Source Code for acm 2004-2005 problems
References: <03d25e16-97d2-4b09-8113-5011c0e0ded9@p28g2000vbn.googlegroups.com>
Message-ID: <f4411a3f-d980-48cc-b9ea-34203b833f4c@o36g2000vbl.googlegroups.com>

On Jul 12, 5:24?pm, Davood Vahdati <davoodvahdati2... at gmail.com>
wrote:
> Dear Sirs And Madams :
>
> it is an Acm programming competition Questions in year 2004-2005 .
> could you please solve problems is question ? I ?Wan't C++ Source Code
> program About this questions OR Problems . thank you for your prompt
> attention to this matter
>
> 2 1
> 4 3
> 5 1
> 4 2
>
<huge chunk of OT content snipped>

looking for the Python content in this post...

mmmmm, nope, didn't find any...

I guess the OP tried on a C++ newsgroup and got told to do his own
homework, so he came here instead?


From gagsl-py2 at yahoo.com.ar  Sun Jul 12 19:13:43 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 12 Jul 2009 20:13:43 -0300
Subject: c++ Source Code for acm 2004-2005 problems
References: <03d25e16-97d2-4b09-8113-5011c0e0ded9@p28g2000vbn.googlegroups.com>
Message-ID: <op.uwy9g5acx6zn5v@gabriel.sleipnir-bsas>

En Sun, 12 Jul 2009 19:24:57 -0300, Davood Vahdati  
<davoodvahdati2009 at gmail.com> escribi?:

> it is an Acm programming competition Questions in year 2004-2005 .
> could you please solve problems is question ? I  Wan't C++ Source Code
> program About this questions OR Problems . thank you for your prompt
> attention to this matter

Not C++ code but Python: A brute force approach to the first problem.

> Parallelogram Counting
> There are n distinct points in the plane, given by their integer
> coordinates. Find the number of parallelograms whose
> vertices lie on these points.

class Point:
   def __init__(self, x, y): self.x, self.y = x, y
   def __repr__(self): return 'Point(%d,%d)' % (self.x, self.y)

class Segment:
   def __init__(self, p0, p1): self.p0, self.p1 = p0, p1
   def is_parallel(self, other):
     return ((self.p1.x-self.p0.x) * (other.p1.y-other.p0.y) -
             (self.p1.y-self.p0.y) * (other.p1.x-other.p0.x) == 0)

points = [
     Point(-2,-1),
     Point(8,9),
     Point(5,7),
     Point(1,1),
     Point(4,8),
     Point(2,0),
     Point(9,8)]

n = 0
for i,A in enumerate(points):
   for B in points[i+1:]:
     AB = Segment(A,B)
     for C in points:
       if C in (A,B): continue
       BC = Segment(B,C)
       for D in points:
         if D in (A,B,C): continue
         CD = Segment(C,D)
         if AB.is_parallel(CD) and BC.is_parallel(Segment(A,D)):
           print A,B,C,D
           n += 1

n /= 4 # ABCD,BCDA,CDAB,DABC ## BACD etc already removed
print n

-- 
Gabriel Genellina



From clp2 at rebertia.com  Sun Jul 12 19:52:06 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 12 Jul 2009 16:52:06 -0700
Subject: multiprocessing and dictionaries
In-Reply-To: <200907121116.13828.bjorn.m.meyer@gmail.com>
References: <200907121116.13828.bjorn.m.meyer@gmail.com>
Message-ID: <50697b2c0907121652j6cf27749xffd6057a3e01f7c@mail.gmail.com>

On Sun, Jul 12, 2009 at 10:16 AM, Bjorn Meyer<bjorn.m.meyer at gmail.com> wrote:
> I am trying to convert a piece of code that I am using the thread module with
> to the multiprocessing module.
>
> The way that I have it set up is a chunk of code reads a text file and assigns
> a dictionary key multiple values from the text file. I am using locks to write
> the values to the dictionary.
> The way that the values are written is as follows:
> ? ? ? ?mydict.setdefault(key, []).append(value)
>
> The problem that I have run into is that using multiprocessing, the key gets
> set, but the values don't get appended.

Don't have much concurrency experience, but have you tried using a
defaultdict instead?
It's possible its implementation might solve the problem.
http://docs.python.org/dev/library/collections.html#collections.defaultdict

Cheers,
Chris
-- 
http://blog.rebertia.com


From Samnsparky at gmail.com  Sun Jul 12 20:01:55 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 17:01:55 -0700 (PDT)
Subject: Webcam + GStreamer
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com> 
	<mailman.3040.1247437820.8015.python-list@python.org>
Message-ID: <4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>

On Jul 12, 4:30?pm, David <da... at pythontoo.com> wrote:
> Sparky wrote:
> > On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
> >> Hello! I need to stream from a webcam in Linux and I need to be able
> >> to analyze the video feed frame by frame with PIL. Currently my web-
> >> cam (Quickcam Chat) only seems to work with GStreamer so a solution
> >> using pygst would be preferred.
>
> >> Thanks for your help,
> >> Sam
>
> > Sorry, to clarify I am just having a hard time capturing frames in a
> > way that I can access with PIL.
>
> Most web cams produce jpeg images so read the note at the bottom here;http://effbot.org/imagingbook/format-jpeg.htm
> What exactly are you trying to do? What have you tried so far and what
> happened may help.
>
> --
> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com

Dear David,

Thank you for your quick response. I have tried a few things. First of
all, I have tried gst-launch-0.10 v4l2src ! ffmpegcolorspace !
pngenc ! filesink location=foo.png. Foo.png comes out sharp enough but
it takes around 2 seconds to complete. I have also tried CVTypes but
it does not run without LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so and,
when it does run, it only displays colored "snow". Here is that code:

import pygame
import Image
from pygame.locals import *
import sys

import opencv
#this is important for capturing/displaying images
from opencv import highgui

camera = highgui.cvCreateCameraCapture(-1)
print "cam:" + str(camera)
def get_image():
	print "here"
	im = highgui.cvQueryFrame(camera)
	#convert Ipl image to PIL image
	return opencv.adaptors.Ipl2PIL(im)

fps = 30.0
pygame.init()
window = pygame.display.set_mode((320,240))
pygame.display.set_caption("WebCam Demo")
screen = pygame.display.get_surface()

while True:
	events = pygame.event.get()
	im = get_image()
	print im.mode
	pg_img = pygame.image.frombuffer(im.tostring(), im.size, im.mode)
	screen.blit(pg_img, (0,0))
	pygame.display.flip()
	pygame.time.delay(int(1000 * 1.0/fps))

Finally, I have gotten pygst to stream video with the example at
http://pygstdocs.berlios.de/pygst-tutorial/webcam-viewer.html but of
course I do not know how to get a hold of that data. Just so you know,
I am trying a primitive type of object tracking. I would use some of
the libraries already available but the two more popular
implementations on Linux (tbeta/ccv and reacTIVision) dont seem to
work with my web cam. I have more info on those non-python attempts at
http://ubuntuforums.org/showthread.php?p=7596908. Unfortunately no one
seemed to respond to that post.

Thanks again,
Sam


From half.italian at gmail.com  Sun Jul 12 20:03:32 2009
From: half.italian at gmail.com (Sean DiZazzo)
Date: Sun, 12 Jul 2009 17:03:32 -0700 (PDT)
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty" 
	exception
References: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu> 
	<mailman.2994.1247271008.8015.python-list@python.org>
Message-ID: <f495ad53-acee-4604-9ccb-2dad18592d86@o9g2000prg.googlegroups.com>

On Jul 10, 5:10?pm, Tim Chase <python.l... at tim.thechases.com> wrote:
> > ? ? ?shutil.rmtree(filename)
> > ? ?File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
> > ? ? ?onerror(os.rmdir, path, sys.exc_info())
> > ? ?File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
> > ? ? ?os.rmdir(path)
> > OSError: [Errno 39] Directory not empty: /path/to/my/dir
>
> > According to the documentation, shutil.rmtree should not care about ?
> > directory being not empty.
>
> This sounds suspiciously like a permission issue. ?rmtree()
> *should* walk the tree removing items *if it can*. ?If a file
> can't be deleted, it treats it as an error. ?rmtree() takes
> parameters for ignore_errors and an onerror callback function, so
> you can catch these error conditions.
>
> -tkc

This one took me a long time to find a solution for.  Check this page,
and see comment #3: http://code.activestate.com/recipes/193736/

I guess if the file is marked as "Read Only" or "Archive", or
whatever, it cannot be deleted with shutil.rmtree()

The key:  win32api.SetFileAttributes(path,
win32con.FILE_ATTRIBUTE_NORMAL)

It will work!

~Sean


From tjreedy at udel.edu  Sun Jul 12 20:15:00 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 12 Jul 2009 20:15:00 -0400
Subject: Question about generators
In-Reply-To: <7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>	<4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
Message-ID: <h3dua1$l12$2@ger.gmane.org>

Cameron Pulsford wrote:

When you start a new thread, you should start a new thread and not 
piggyback on an existing thread.



From cameron.pulsford at gmail.com  Sun Jul 12 21:24:29 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Sun, 12 Jul 2009 21:24:29 -0400
Subject: Question about generators
In-Reply-To: <h3dua1$l12$2@ger.gmane.org>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>	<4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
Message-ID: <B7472107-5B71-4661-891D-3B93DB4EF674@gmail.com>

itertools.chain() did it, thanks!

As far as the primes generator, it does not generate any non-primes.  
All primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5)  
where is x is [1, 2, ..., n]. The only time it doesn't generate a  
prime is when x + (1 or 5) % 5 == 0. Which is what that last part is  
making sure doesn't happen. I'm not a mathematician or anything so  
correct me if I'm wrong, but that's what I've read.

Also sorry if this was piggy backed, I started the thread as a fresh e- 
mail to python-list at python.org, sorry if I messed something up!

On Jul 12, 2009, at 8:15 PM, Terry Reedy wrote:

> Cameron Pulsford wrote:
>
> When you start a new thread, you should start a new thread and not  
> piggyback on an existing thread.
>
> -- 
> http://mail.python.org/mailman/listinfo/python-list



From david at pythontoo.com  Sun Jul 12 21:38:43 2009
From: david at pythontoo.com (David)
Date: Sun, 12 Jul 2009 21:38:43 -0400
Subject: Webcam + GStreamer
In-Reply-To: <4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>
	<mailman.3040.1247437820.8015.python-list@python.org>
	<4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>
Message-ID: <4A5A9023.8070600@pythontoo.com>

Sparky wrote:
> On Jul 12, 4:30 pm, David <da... at pythontoo.com> wrote:
>> Sparky wrote:
>>> On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
>>>> Hello! I need to stream from a webcam in Linux and I need to be able
>>>> to analyze the video feed frame by frame with PIL. Currently my web-
>>>> cam (Quickcam Chat) only seems to work with GStreamer so a solution
>>>> using pygst would be preferred.
>>>> Thanks for your help,
>>>> Sam
>>> Sorry, to clarify I am just having a hard time capturing frames in a
>>> way that I can access with PIL.
>> Most web cams produce jpeg images so read the note at the bottom here;http://effbot.org/imagingbook/format-jpeg.htm
>> What exactly are you trying to do? What have you tried so far and what
>> happened may help.
>>
>> --
>> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com
> 
> Dear David,
> 
> Thank you for your quick response. I have tried a few things. First of
> all, I have tried gst-launch-0.10 v4l2src ! ffmpegcolorspace !
> pngenc ! filesink location=foo.png. Foo.png comes out sharp enough but
> it takes around 2 seconds to complete. I have also tried CVTypes but
> it does not run without LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so and,
> when it does run, it only displays colored "snow". Here is that code:
> 
> import pygame
> import Image
> from pygame.locals import *
> import sys
> 
> import opencv
> #this is important for capturing/displaying images
> from opencv import highgui
> 
> camera = highgui.cvCreateCameraCapture(-1)
> print "cam:" + str(camera)
> def get_image():
> 	print "here"
> 	im = highgui.cvQueryFrame(camera)
> 	#convert Ipl image to PIL image
> 	return opencv.adaptors.Ipl2PIL(im)
> 
> fps = 30.0
> pygame.init()
> window = pygame.display.set_mode((320,240))
> pygame.display.set_caption("WebCam Demo")
> screen = pygame.display.get_surface()
> 
> while True:
> 	events = pygame.event.get()
> 	im = get_image()
> 	print im.mode
> 	pg_img = pygame.image.frombuffer(im.tostring(), im.size, im.mode)
> 	screen.blit(pg_img, (0,0))
> 	pygame.display.flip()
> 	pygame.time.delay(int(1000 * 1.0/fps))
> 
> Finally, I have gotten pygst to stream video with the example at
> http://pygstdocs.berlios.de/pygst-tutorial/webcam-viewer.html but of
> course I do not know how to get a hold of that data. Just so you know,
> I am trying a primitive type of object tracking. I would use some of
> the libraries already available but the two more popular
> implementations on Linux (tbeta/ccv and reacTIVision) dont seem to
> work with my web cam. I have more info on those non-python attempts at
> http://ubuntuforums.org/showthread.php?p=7596908. Unfortunately no one
> seemed to respond to that post.
> 
> Thanks again,
> Sam
See if this gets you started, I got it working here with a video4linux2 cam.
http://code.google.com/p/python-video4linux2/
here is what I have, I think it is the same;
http://dwabbott.com/python-video4linux2-read-only/
let me know how you make out.
-david


-- 
Powered by Gentoo GNU/Linux
http://linuxcrazy.com


From drobinow at gmail.com  Sun Jul 12 22:00:15 2009
From: drobinow at gmail.com (David Robinow)
Date: Sun, 12 Jul 2009 22:00:15 -0400
Subject: Question about generators
In-Reply-To: <B7472107-5B71-4661-891D-3B93DB4EF674@gmail.com>
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
	<B7472107-5B71-4661-891D-3B93DB4EF674@gmail.com>
Message-ID: <4eb0089f0907121900o3f8f3416vd519c1487465fb1a@mail.gmail.com>

On Sun, Jul 12, 2009 at 9:24 PM, Cameron
Pulsford<cameron.pulsford at gmail.com> wrote:
> As far as the primes generator, it does not generate any non-primes. All
> primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5) where is x is
> [1, 2, ..., n]. The only time it doesn't generate a prime is when x + (1 or
> 5) % 5 == 0. Which is what that last part is making sure doesn't happen. I'm
> not a mathematician or anything so correct me if I'm wrong, but that's what
> I've read.
 All you're doing is eliminating numbers divisible by 2,3, and 5.
Your generator includes   49  (7 * 7),  77 (7*11), 91 (7*13), 121 (11*11),  etc.


From sjmachin at lexicon.net  Sun Jul 12 22:26:20 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 12 Jul 2009 19:26:20 -0700 (PDT)
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org> 
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org> 
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org> 
	<mailman.3044.1247448559.8015.python-list@python.org>
Message-ID: <0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>

On Jul 13, 11:24?am, Cameron Pulsford <cameron.pulsf... at gmail.com>
wrote:

> As far as the primes generator, it does not generate any non-primes. ?
> All primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5) ?
> where is x is [1, 2, ..., n]. The only time it doesn't generate a ?
> prime is when x + (1 or 5) % 5 == 0. Which is what that last part is ?
> making sure doesn't happen. I'm not a mathematician or anything so
> correct me if I'm wrong, but that's what I've read.

Where did you read that? Have you tried to verify it, like this:

| >>> [6*i+j for i in range(1, 21) for j in (1, 5) if (i+j) % 5]
| [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67,
71, 73, 77, 79, 83, 89, 91, 97, 101, 103, 107, 109, 113, 119, 121]

49, 77, 91, and 121 are not prime.



From Samnsparky at gmail.com  Sun Jul 12 22:54:21 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 19:54:21 -0700 (PDT)
Subject: Webcam + GStreamer
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com> 
	<mailman.3040.1247437820.8015.python-list@python.org>
	<4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>
	<mailman.3045.1247449441.8015.python-list@python.org>
Message-ID: <8aac1115-3dcc-4e91-94d6-ac4204879420@d9g2000prh.googlegroups.com>

On Jul 12, 7:38?pm, David <da... at pythontoo.com> wrote:
> Sparky wrote:
> > On Jul 12, 4:30 pm, David <da... at pythontoo.com> wrote:
> >> Sparky wrote:
> >>> On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
> >>>> Hello! I need to stream from a webcam in Linux and I need to be able
> >>>> to analyze the video feed frame by frame with PIL. Currently my web-
> >>>> cam (Quickcam Chat) only seems to work with GStreamer so a solution
> >>>> using pygst would be preferred.
> >>>> Thanks for your help,
> >>>> Sam
> >>> Sorry, to clarify I am just having a hard time capturing frames in a
> >>> way that I can access with PIL.
> >> Most web cams produce jpeg images so read the note at the bottom here;http://effbot.org/imagingbook/format-jpeg.htm
> >> What exactly are you trying to do? What have you tried so far and what
> >> happened may help.
>
> >> --
> >> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com
>
> > Dear David,
>
> > Thank you for your quick response. I have tried a few things. First of
> > all, I have tried gst-launch-0.10 v4l2src ! ffmpegcolorspace !
> > pngenc ! filesink location=foo.png. Foo.png comes out sharp enough but
> > it takes around 2 seconds to complete. I have also tried CVTypes but
> > it does not run without LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so and,
> > when it does run, it only displays colored "snow". Here is that code:
>
> > import pygame
> > import Image
> > from pygame.locals import *
> > import sys
>
> > import opencv
> > #this is important for capturing/displaying images
> > from opencv import highgui
>
> > camera = highgui.cvCreateCameraCapture(-1)
> > print "cam:" + str(camera)
> > def get_image():
> > ? ?print "here"
> > ? ?im = highgui.cvQueryFrame(camera)
> > ? ?#convert Ipl image to PIL image
> > ? ?return opencv.adaptors.Ipl2PIL(im)
>
> > fps = 30.0
> > pygame.init()
> > window = pygame.display.set_mode((320,240))
> > pygame.display.set_caption("WebCam Demo")
> > screen = pygame.display.get_surface()
>
> > while True:
> > ? ?events = pygame.event.get()
> > ? ?im = get_image()
> > ? ?print im.mode
> > ? ?pg_img = pygame.image.frombuffer(im.tostring(), im.size, im.mode)
> > ? ?screen.blit(pg_img, (0,0))
> > ? ?pygame.display.flip()
> > ? ?pygame.time.delay(int(1000 * 1.0/fps))
>
> > Finally, I have gotten pygst to stream video with the example at
> >http://pygstdocs.berlios.de/pygst-tutorial/webcam-viewer.htmlbut of
> > course I do not know how to get a hold of that data. Just so you know,
> > I am trying a primitive type of object tracking. I would use some of
> > the libraries already available but the two more popular
> > implementations on Linux (tbeta/ccv and reacTIVision) dont seem to
> > work with my web cam. I have more info on those non-python attempts at
> >http://ubuntuforums.org/showthread.php?p=7596908. Unfortunately no one
> > seemed to respond to that post.
>
> > Thanks again,
> > Sam
>
> See if this gets you started, I got it working here with a video4linux2 cam.http://code.google.com/p/python-video4linux2/
> here is what I have, I think it is the same;http://dwabbott.com/python-video4linux2-read-only/
> let me know how you make out.
> -david
>
> --
> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com

I gave it a shot and here is what I got:

sam at sam-laptop:~/python-video4linux2-read-only$ ./pyv4l2.py
Available devices:  ['/dev/video0']
	/dev/video0
Capabilities:
	Capture
	ReadWrite
	Streaming
Input 0:
		Name:	zc3xx
		Type:	camera
		Standards: []
Pixel formats:
	JPEG	JPEG
Resolutions:
Segmentation fault

-------------------------------------

sam at sam-laptop:~/python-video4linux2-read-only$ ./streampics.py /dev/
video0 0 BGR3 640 480 testpics
Trying to create directory pics
Recording /dev/video0:0 with format JPEG at (640, 480)
Traceback (most recent call last):
  File "./streampics.py", line 94, in <module>
    Run()
  File "./streampics.py", line 78, in Run
    d.SetupStreaming(5, StreamCallback)
  File "/home/sam/python-video4linux2-read-only/pyv4l2.py", line 682,
in SetupStreaming
    self.StreamOn()
  File "/home/sam/python-video4linux2-read-only/pyv4l2.py", line 636,
in StreamOn
    lib.Error()
Exception: Could not start streaming:	22: Invalid argument
*** glibc detected *** python: free(): invalid next size (fast):
0x0a2aeff0 ***

Any suggestions?

Thanks,
Sam


From cameron.pulsford at gmail.com  Sun Jul 12 23:17:31 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Sun, 12 Jul 2009 23:17:31 -0400
Subject: Question about generators
In-Reply-To: <0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
	<mailman.3044.1247448559.8015.python-list@python.org>
	<0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
Message-ID: <BEC2887C-8E6F-4FBB-A723-257AF19C6C3E@gmail.com>

I read it on the haskell site in their sieves/prime wheel section, I  
guess I misunderstood something. (east to do over there...) I did  
verify it against established list of primes and other generators I've  
written that use more normal methods, but I only hand verified it.

It is at least interesting though, I can probably extend it to check  
for primality by using a more normal sieve method. It might be pretty  
fast too because generally it does only generate primes, and the few  
non primes it does generate could be caught quickly using a scratching  
out technique.

When I was initially looking at it there are some interesting patterns  
I might be able to extend into a generator that would yield only  
correct sets of numbers for the 6x + n pattern.


On Jul 12, 2009, at 10:26 PM, John Machin wrote:

> On Jul 13, 11:24 am, Cameron Pulsford <cameron.pulsf... at gmail.com>
> wrote:
>
>> As far as the primes generator, it does not generate any non-primes.
>> All primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5)
>> where is x is [1, 2, ..., n]. The only time it doesn't generate a
>> prime is when x + (1 or 5) % 5 == 0. Which is what that last part is
>> making sure doesn't happen. I'm not a mathematician or anything so
>> correct me if I'm wrong, but that's what I've read.
>
> Where did you read that? Have you tried to verify it, like this:
>
> | >>> [6*i+j for i in range(1, 21) for j in (1, 5) if (i+j) % 5]
> | [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67,
> 71, 73, 77, 79, 83, 89, 91, 97, 101, 103, 107, 109, 113, 119, 121]
>
> 49, 77, 91, and 121 are not prime.
>
> -- 
> http://mail.python.org/mailman/listinfo/python-list



From vincent.gulinao at gmail.com  Mon Jul 13 01:06:11 2009
From: vincent.gulinao at gmail.com (Vincent Gulinao)
Date: Mon, 13 Jul 2009 13:06:11 +0800
Subject: Infinite loops and synchronization
Message-ID: <fcc3e6170907122206t59a17747kef305ef79066a6c2@mail.gmail.com>

lst = list()

(lst populated by async twisted deferred callbacks)

while True:
	if len(lst) == SOME_NUMBER:
		return lst

Q1: is this a common OK practice? I'm worried infinite loops hogs memory.
Q2: operating on list from threads (mostly appends) must be safe,
right (synchronization)?


From sjmachin at lexicon.net  Mon Jul 13 01:08:30 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 12 Jul 2009 22:08:30 -0700 (PDT)
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org> 
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org> 
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org> 
	<mailman.3044.1247448559.8015.python-list@python.org>
	<0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
	<mailman.3047.1247455341.8015.python-list@python.org>
Message-ID: <b8ccc8a9-b320-4f5c-b3ea-1be036f2de8f@l5g2000pra.googlegroups.com>

On Jul 13, 1:17?pm, Cameron Pulsford <cameron.pulsf... at gmail.com>
wrote:
> I read it on the haskell site in their sieves/prime wheel section, I ?
> guess I misunderstood something. (east to do over there...) I did ?
> verify it against established list of primes and other generators I've ?
> written that use more normal methods, but I only hand verified it.

"to verify" something means to ensure the truth or correctness, NOT
attempt to ensure ;-)


From amit.kumar.iitr at gmail.com  Mon Jul 13 02:42:02 2009
From: amit.kumar.iitr at gmail.com (Amit)
Date: Sun, 12 Jul 2009 23:42:02 -0700 (PDT)
Subject: compilation problem of python on AIX 6.1
Message-ID: <51c556a8-7277-474d-821f-190adf155c75@f16g2000vbf.googlegroups.com>

Hello

I want to intsall python on my AIX 6.1 Box.
I couldn't get any rpm for python 2.5.x for AIX 6.1.

THen I decided to compile python 2.5.4 on my AIX box. I downloaded the
python source code from www.python.org and tried to compile on my AIX
both using gcc.

step 1 ./configure --with-gcc
configuration runs successfully

step 2 make
it gives me error

	case $MAKEFLAGS in  *-s*)  CC='gcc -pthread' LDSHARED='./Modules/
ld_so_aix gcc -pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -
fwrapv -O3 -Wall -Wstrict-prototypes' ./python -E ./setup.py -q
build;;  *)  CC='gcc -pthread' LDSHARED='./Modules/ld_so_aix gcc -
pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes' ./python -E ./setup.py build;;  esac
running build
running build_ext
building 'bz2' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes -I. -I/avre/Python-2.5.4/./Include -I. -IInclude -
I./Include -I/avre/Python-2.5.4/Include -I/avre/Python-2.5.4 -c /avre/
Python-2.5.4/Modules/bz2module.c -o build/temp.aix-6.1-2.5/avre/
Python-2.5.4/Modules/bz2module.o
building '_tkinter' extension
./Modules/ld_so_aix gcc -pthread -bI:Modules/python.exp build/
temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/_tkinter.o build/
temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/tkappinit.o -L/usr/X11/lib -
ltk8.4 -ltcl8.4 -lX11 -o build/lib.aix-6.1-2.5/_tkinter.so
*** WARNING: renaming "_tkinter" since importing it failed: 	0509-022
Cannot load module build/lib.aix-6.1-2.5.
	0509-026 System error: A file or directory in the path name does not
exist.

plz suggest


From piet at cs.uu.nl  Mon Jul 13 03:56:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 09:56:08 +0200
Subject: multiprocessing and dictionaries
References: <mailman.3031.1247418982.8015.python-list@python.org>
Message-ID: <m2y6qt2ezr.fsf@cs.uu.nl>

>>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:

>BM> I am trying to convert a piece of code that I am using the thread module with 
>BM> to the multiprocessing module.

>BM> The way that I have it set up is a chunk of code reads a text file and assigns 
>BM> a dictionary key multiple values from the text file. I am using locks to write 
>BM> the values to the dictionary.
>BM> The way that the values are written is as follows:
>BM> 	mydict.setdefault(key, []).append(value)

>BM> The problem that I have run into is that using multiprocessing, the key gets 
>BM> set, but the values don't get appended.
>BM> I've even tried the Manager().dict() option, but it doesn't seem to work.

>BM> Is this not supported at this time or am I missing something?

I think you should give more information. Try to make a *minimal* program
that shows the problem and include it in your posting or supply a
download link.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 04:01:53 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 10:01:53 +0200
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
	<mailman.3044.1247448559.8015.python-list@python.org>
	<0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
	<mailman.3047.1247455341.8015.python-list@python.org>
Message-ID: <m2tz1h2eq6.fsf@cs.uu.nl>

>>>>> Cameron Pulsford <cameron.pulsford at gmail.com> (CP) wrote:

>CP> I read it on the haskell site in their sieves/prime wheel section,
>CP> I guess I misunderstood something. (east to do over there...) I did
>CP> verify it against established list of primes and other generators
>CP> I've written that use more normal methods, but I only hand verified
>CP> it.

If it is used in a sieve then the non-primes will be sieved out.

>CP> It is at least interesting though, I can probably extend it to
>CP> check for primality by using a more normal sieve method. It might
>CP> be pretty fast too because generally it does only generate primes,
>CP> and the few non primes it does generate could be caught quickly
>CP> using a scratching out technique.

it does only generate primes => it does generate all primes.

>CP> When I was initially looking at it there are some interesting
>CP> patterns I might be able to extend into a generator that would
>CP> yield only correct sets of numbers for the 6x + n pattern.

As I wrote in my previous reply, in your use case the non-primes are
harmless. But it is useful to reflect that in the naming of your
identifiers. 

*And please, don't top post.*

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 04:53:36 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 10:53:36 +0200
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <m2my792cbz.fsf@cs.uu.nl>

>>>>> Vincent Gulinao <vincent.gulinao at gmail.com> (VG) wrote:

>VG> lst = list()
>VG> (lst populated by async twisted deferred callbacks)

>VG> while True:
>VG> 	if len(lst) == SOME_NUMBER:
>VG> 		return lst

>VG> Q1: is this a common OK practice? I'm worried infinite loops hogs memory.
>VG> Q2: operating on list from threads (mostly appends) must be safe,
>VG> right (synchronization)?

I am not familiar enough with twisted, but I think the principle is
independent from twisted.

This loop will not hog memory but it will hog CPU time.

You should use a synchronisation construct like threading.Condition or a
Semaphore. Here is my suggestion with a Condition:

Global somewhere:
       lst_cond = Condition()

In your loop:

lst = list()  # Why not lst = []?

while True: # strange while/if combo
	if len(lst) == SOME_NUMBER:
		return lst

Make that:

with lst_cond:
    while len(lst) < SOME_NUMBER:
        lst_cond.wait()
    return lst

In the callback:

with lst_cond:
    lst.append(new_value)
    lst_cond.notify()

In case you don't have a python that supports the with statement (not
even `from future') you should use:

lst_cond.acquire()
try:
    .....
finally:
    lst_cond.release()

I think the solution with a semaphore is less elegant.

global: sem = Semaphore()

loop:
for i in range(SOME_NUMBER): 
    sem.acquire()
return lst

In callback:

lst.append(new_value)
sem.release()

*Be careful: I haven't tested this code (not even syntax checked). So
consider it pseudo code.*
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From vinay_sajip at yahoo.co.uk  Mon Jul 13 05:39:40 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Mon, 13 Jul 2009 02:39:40 -0700 (PDT)
Subject: the ultimate logging facility for debugging code
References: <mailman.2939.1247218807.8015.python-list@python.org>
Message-ID: <69032a2b-0f8e-4174-b996-6203387c4058@l5g2000vbp.googlegroups.com>

On Jul 10, 10:39?am, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> Greetings,
>
> Sorry for the dubious title :o). I was wandering if there is a standard
> (or reliable) python module that implements the following feature:
>
> http://code.activestate.com/recipes/198078/
> ?>>>Recipe 198078: Wrapping method calls (meta-class example)
> ?>>>
> ?>>>A metaclass is used to wrap all (or just some) methods forlogging
> purposes. The underlying mechanism can be used as well to check pre/post
> conditions, attribute access,... The basic point is, that the actual
> class must not be changed in any way to achive the desired effect.
>
> I had to adapt the code to some of my needs, but now it's almost
> working, by simply defining a metaclass for any of my class, I get the
> class methods calls logged with the instance that called the method, the
> method name, the call line in the file, the parameter **value** ?passed
> to the method and the returned value.
> It just saved me from hours of ipython interactive debugging with the
> old print way, and to beauty of it: I don't have to write any
> "self._log('Please log me')" line.
>
> As it is so useful, I bet there is a module that is doing this in a more
> reliable way that I did. Anyone has heard of it ?
>
> Jean-Michel

Check out the Python Decorator Library: http://wiki.python.org/moin/PythonDecoratorLibrary

and you should be able to adapt what you find there to your needs.

Regards,

Vinay Sajip


From pdpinheiro at gmail.com  Mon Jul 13 06:12:03 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Mon, 13 Jul 2009 03:12:03 -0700 (PDT)
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <c44bae99-b3b8-4130-82d7-f2853302c3ab@f16g2000vbf.googlegroups.com>

On Jul 13, 6:06?am, Vincent Gulinao <vincent.guli... at gmail.com> wrote:
> lst = list()
>
> (lst populated by async twisted deferred callbacks)
>
> while True:
> ? ? ? ? if len(lst) == SOME_NUMBER:
> ? ? ? ? ? ? ? ? return lst
>
> Q1: is this a common OK practice? I'm worried infinite loops hogs memory.
> Q2: operating on list from threads (mostly appends) must be safe,
> right (synchronization)?

Q1: I'll answer your question with another. What's so fundamentally
different between your infinite loop and this one:

while len(lst) != SOME_NUMBER:
  pass
return lst

which is not an "infinite loop"[1]. Why would yours be any worse in
terms of memory than mine? Are you allocating anything that would hog
memory? Of course, like Piet said, it *will* hog your CPU, so you want
a time.sleep(.1) in there, at the least. Of course, the question is:
why aren't you using a semaphore to let you know you can proceed, and
make the provider increment the semaphore?

[1] -- well, it can be, if len(lst) == SOME_NUMBER never comes about,
and I'd hazard a guess that that's pretty much where your fear of
memory hogging comes from: it's easy to allocate stuff and not
deallocate it within a cycle, only to find the bounds on that cycle
going awry.


From ganesh.gbg at gmail.com  Mon Jul 13 06:34:19 2009
From: ganesh.gbg at gmail.com (gganesh)
Date: Mon, 13 Jul 2009 03:34:19 -0700 (PDT)
Subject: simple question about Dictionary type containing  List objects
Message-ID: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>

Hi group,
I have a dict object like
emails={'mycontacts': [ 'xxx at gmail.com, 'yy at gmail.com',
'zz at gmail.com'], 'myname':['gganesh']}
I need to get the lenght of the list mycontacts ,like
mycontacts_numbers=3
help me to solve
Thanks




From contact at xavierho.com  Mon Jul 13 06:36:55 2009
From: contact at xavierho.com (Xavier Ho)
Date: Mon, 13 Jul 2009 18:36:55 +0800
Subject: simple question about Dictionary type containing List objects
In-Reply-To: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>
References: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>
Message-ID: <2d56febf0907130336x6950051em7903f66b5dfc5349@mail.gmail.com>

On Mon, Jul 13, 2009 at 6:34 PM, gganesh <ganesh.gbg at gmail.com> wrote:

> Hi group,
> I have a dict object like
> emails={'mycontacts': [ 'xxx at gmail.com, 'yy at gmail.com',
> 'zz at gmail.com'], 'myname':['gganesh']}
> I need to get the lenght of the list mycontacts ,like
> mycontacts_numbers=3 <http://mail.python.org/mailman/listinfo/python-list>
>

>>> len(emails['mycontacts'])
3

HTH,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/f2807dbb/attachment.html>

From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:22:36 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:22:36 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
	<h3bogf$oo0$1@panix3.panix.com>
Message-ID: <h3f5dt$dld$3@lust.ihug.co.nz>

In message <h3bogf$oo0$1 at panix3.panix.com>, Aahz wrote:

> In article <h3bagu$52m$4 at lust.ihug.co.nz>,
> Lawrence D'Oliveiro  <ldo at geek-central.gen.new_zealand> wrote:
>>In message <h37gv5$r81$1 at panix3.panix.com>, Aahz wrote:
>>>
>>> It helps to remember that names and namespaces are in many
>>> ways syntactic sugar for dicts or lists.
>>
>>Interesting, though, that Python insists on maintaining a distinction
>>between c["x"] and c.x, whereas JavaScript doesn't bother.
> 
> Why do you say "insists"?
> 
> class AttrDict:
>     def __getitem__(self, key):
>         return getattr(self, key)

OK, let's try it:

    >>> c = {}
    >>> c["x"] = 3
    >>> c.x = 4   
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    AttributeError: 'dict' object has no attribute 'x'
    >>> class AttrDict:
    ...     def __getitem__(self, key):
    ...         return getattr(self, key)
    ...
    >>> c.x = 4
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    AttributeError: 'dict' object has no attribute 'x'

Nope, still doesn't work...



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:24:03 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:24:03 +1200
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <h3f5gj$dld$4@lust.ihug.co.nz>

In message <mailman.3048.1247462046.8015.python-list at python.org>, Vincent 
Gulinao wrote:

> Q1: is this a common OK practice? I'm worried infinite loops hogs memory.

The problem is not that the loop is infinite, but that it busy-waits, 
hogging CPU.



From eckhardt at satorlaser.com  Mon Jul 13 07:25:29 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Mon, 13 Jul 2009 13:25:29 +0200
Subject: simple question about Dictionary type containing  List objects
References: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>
Message-ID: <96iri6-s13.ln1@satorlaser.homedns.org>

gganesh wrote:
> I have a dict object like
> emails={'mycontacts': [ 'xxx at gmail.com, 'yy at gmail.com',
> 'zz at gmail.com'], 'myname':['gganesh']}
> I need to get the lenght of the list mycontacts ,like
> mycontacts_numbers=3

mycontacts = emails['mycontacts']
mycontacts_number = len(mycontacts)

A list doesn't change in behaviour when it is contained in a dictionary.

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:27:33 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:27:33 +1200
Subject: MySQLdb + SSH Tunnel
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
	<mailman.3035.1247427709.8015.python-list@python.org>
Message-ID: <h3f5n5$dld$5@lust.ihug.co.nz>

In message <mailman.3035.1247427709.8015.python-list at python.org>, Emile van 
Sebille wrote:

> ssh with something like...
> 
> ssh -lroot -L3306:C:3306 B
> 
> Watch out for other instances of mysql on A or B...

You can use a non-default local port and specify that in your local 
connection parameters. Similarly you can tell the remote server to use a 
non-default port in its /etc/my.cnf.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:29:39 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:29:39 +1200
Subject: Looking for a tool to checkfor python script backward
	compatibility
References: <4a59951a$0$10853$426a74cc@news.free.fr>
Message-ID: <h3f5r3$dld$6@lust.ihug.co.nz>

In message <4a59951a$0$10853$426a74cc at news.free.fr>, Baptiste Lepilleur 
wrote:

> I'm looking for a tool that could be used in a pre-commit step to check
> that only features available in a "old" python version are used, say
> python 2.3 for example.

The only sure way would be to run the script under an appropriately old 
version of Python.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:35:43 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:35:43 +1200
Subject: send keys to focused window
References: <MPG.24c0392b71e8a0eb989680@news.bintube.com>
Message-ID: <h3f66f$dld$7@lust.ihug.co.nz>

In message <MPG.24c0392b71e8a0eb989680 at news.bintube.com>, Broken wrote:

> I am new to Python, and I'm miserably failing to send specific keys to
> (say) notepad.

I don't understand why you need to automate a GUI front-end, meant for human
use, to a function that can be directly performed without that front-end
anyway.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:37:09 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:37:09 +1200
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
	<mailman.2880.1247134886.8015.python-list@python.org>
	<652cca82-44a3-473f-b640-c2336a9cf929@v15g2000prn.googlegroups.com>
Message-ID: <h3f695$dld$8@lust.ihug.co.nz>

In message <652cca82-44a3-473f-b640-
c2336a9cf929 at v15g2000prn.googlegroups.com>, Rajat wrote:

> ... my whole idea is to close the wordpad / notepad application so that I
> can delete the file and the directory where this file resides.

Don't you think the user might have that application open for a reason?



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:39:34 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:39:34 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<4a538a71$0$30236$9b4e6d93@newsspool1.arcor-online.net>
Message-ID: <h3f6dn$dld$9@lust.ihug.co.nz>

In message <4a538a71$0$30236$9b4e6d93 at newsspool1.arcor-online.net>, Stefan 
Behnel wrote:

> Lawrence D'Oliveiro wrote:
>>
>> I wonder how many people have been tripped up by the fact that
>> 
>>     ++n
>> 
>> and
>> 
>>     --n
>> 
>> fail silently for numeric-valued n.
> 
> I doubt that there are many. Plus, you misspelled them from the more
> obvious
> 
> n++
> 
> and
> 
> n--
> 
> which *do* fail with a SyntaxError.

Funny, you accuse me of "misspelling", when it's _your_ version that fails 
with errors!



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:44:32 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:44:32 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
	<4a531512$0$9355$426a74cc@news.free.fr>
	<fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>
	<mailman.2787.1246986627.8015.python-list@python.org>
Message-ID: <h3f6n0$dld$10@lust.ihug.co.nz>

In message <mailman.2787.1246986627.8015.python-list at python.org>, MRAB 
wrote:

> I wonder whether the problem with assignment in conditionals in C is due
> to the assignment operator being "=". If it was ":=", would the error
> still occur?

One of the original C designers, Kernighan or Ritchie, admitted that he made 
the assignment operator "=" instead of ":=" just to save typing one 
character, because he thought assignments were more common than tests for 
equality.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:47:10 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:47:10 +1200
Subject: Blocking XMPP API?
References: <mailman.2893.1247147391.8015.python-list@python.org>
Message-ID: <h3f6ru$dld$11@lust.ihug.co.nz>

In message <mailman.2893.1247147391.8015.python-list at python.org>, Gabriel 
Rossetti wrote:

> I am looking for blocking XMPP API. I'm wanting to make a webservice
> that uses XMPP, but all the XMPP libs I find are non-blocking (i.e. w/
> callbacks).

So why not have the caller sleep or something until the callback is invoked?

It's easier to turn an async API into a synchronous one than the other way 
round.



From piet at cs.uu.nl  Mon Jul 13 08:15:07 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 14:15:07 +0200
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
	<h3bogf$oo0$1@panix3.panix.com> <h3f5dt$dld$3@lust.ihug.co.nz>
Message-ID: <m24otg3hkk.fsf@cs.uu.nl>

>>>>> Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> (LD) wrote:

>LD> In message <h3bogf$oo0$1 at panix3.panix.com>, Aahz wrote:

>Aahz> class AttrDict:
>Aahz> def __getitem__(self, key):
>Aahz> return getattr(self, key)

>LD> OK, let's try it:

>LD> >>> c = {}
>LD> >>> c["x"] = 3
>LD> >>> c.x = 4   
>LD>     Traceback (most recent call last):
>LD>       File "<stdin>", line 1, in <module>
>LD>     AttributeError: 'dict' object has no attribute 'x'
>LD> >>> class AttrDict:
>LD>     ...     def __getitem__(self, key):
>LD>     ...         return getattr(self, key)
>LD>     ...
>LD> >>> c.x = 4
>LD>     Traceback (most recent call last):
>LD>       File "<stdin>", line 1, in <module>
>LD>     AttributeError: 'dict' object has no attribute 'x'

>LD> Nope, still doesn't work...

Of course you need c = AttrDict()

And to get c.x = 4 working you also need a __setitem__. 
And to get c["x"] working AtrrDict should subclass dict:

>>> class AttrDict(dict):

but these are only minor details :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From dzizes451 at gmail.com  Mon Jul 13 09:07:52 2009
From: dzizes451 at gmail.com (dzizes)
Date: Mon, 13 Jul 2009 06:07:52 -0700 (PDT)
Subject: how to set timeout while colling a soap method?
Message-ID: <24461403.post@talk.nabble.com>


Hello!

I wrote some some python code for executing a soap method:

import SOAPpy
from SOAPpy import WSDL

_server = WSDL.Proxy(some wsdl)
r=_server.generuj(some parameters...)
print r.encode('cp1250')

It works fine. However, the execution time of this soap method might be
long. Therefore, I would like to set a timeout like 1 minute, after which I
would post a timeoute message.

Any ideas?
Greats,


-- 
View this message in context: http://www.nabble.com/how-to-set-timeout-while-colling-a-soap-method--tp24461403p24461403.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From denis-bz-gg at t-online.de  Mon Jul 13 09:11:09 2009
From: denis-bz-gg at t-online.de (denis)
Date: Mon, 13 Jul 2009 06:11:09 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
Message-ID: <07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>

Matt, how many words are you looking for, in how long a string ?
Were you able to time any( substr in long_string ) against re.compile
( "|".join( list_items )) ?
(REs are my method of choice, but different inputs of course give
different times --
see google regex speed site:groups.google.com /
site:stackoverflow.com .)

cheers
  -- denis




From seldan24 at gmail.com  Mon Jul 13 09:26:19 2009
From: seldan24 at gmail.com (seldan24)
Date: Mon, 13 Jul 2009 06:26:19 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
Message-ID: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>

Hello,

I'm fairly new at Python so hopefully this question won't be too
awful.  I am writing some code that will FTP to a host, and want to
catch any exception that may occur, take that and print it out
(eventually put it into a log file and perform some alerting action).
I've figured out two different ways to do this, and am wondering which
is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
to understand exactly what occurs for each one.

The first example:

from ftplib import FTP
try:
    ftp = FTP(ftp_host)
    ftp.login(ftp_user, ftp_pass)
except Exception, err:
    print err

This works fine.  I read through the documentation, and my
understanding is that there is a built-in exceptions module in python,
that is automatically available in a built-in namespace.  Within that
module is an 'Exception' class which would contain whatever exception
is thrown.  So, I'm passing that to the except, along with err to hold
the value and then print it out.

The second example:

from ftplib import FTP
import sys
try:
    ftp = FTP(ftp_host)
    ftp.login(ftp_user, ftp_pass)
except:
    print sys.exc_info()

Here I, for the most part, get the same thing.  I'm not passing
anything to except and just printing out the exception using a method
defined in the sys module.

So, I'm new to Python... I've made it this far and am happy, but want
to make sure I'm coding correctly from the start.  Which method is the
better/cleaner/more standard way to continue?  Thanks for any help.


From dsdale24 at gmail.com  Mon Jul 13 09:38:17 2009
From: dsdale24 at gmail.com (Darren Dale)
Date: Mon, 13 Jul 2009 06:38:17 -0700 (PDT)
Subject: Is it possible to use keyword arguments from C?
Message-ID: <94892b60-b4cb-40fc-8c9d-7cfb7d1c00ed@q35g2000vbi.googlegroups.com>

I am learning about the python C-api in order to contribute a feature
to numpy. I see a discussion (http://docs.python.org/extending/
extending.html#keyword-parameters-for-extension-functions) on how to
create a function or method  in C that accepts kwargs, but is it
possible to call such a method from C using kwargs rather than
positional arguments?


From dsdale24 at gmail.com  Mon Jul 13 09:47:41 2009
From: dsdale24 at gmail.com (Darren Dale)
Date: Mon, 13 Jul 2009 06:47:41 -0700 (PDT)
Subject: Is it possible to use keyword arguments from C?
References: <94892b60-b4cb-40fc-8c9d-7cfb7d1c00ed@q35g2000vbi.googlegroups.com>
Message-ID: <29a66e7b-1263-4c06-ab01-017b471d53d1@p36g2000vbn.googlegroups.com>

On Jul 13, 9:38?am, Darren Dale <dsdal... at gmail.com> wrote:
> I am learning about the python C-api in order to contribute a feature
> to numpy. I see a discussion (http://docs.python.org/extending/
> extending.html#keyword-parameters-for-extension-functions) on how to
> create a function or method ?in C that accepts kwargs, but is it
> possible to call such a method from C using kwargs rather than
> positional arguments?

The answer was yes, this can be done. I found a short discussion at
the bottom of section 1.6: http://docs.python.org/extending/extending.html#calling-python-functions-from-c


From tonylay at gmail.com  Mon Jul 13 09:57:29 2009
From: tonylay at gmail.com (Tony Lay)
Date: Mon, 13 Jul 2009 06:57:29 -0700 (PDT)
Subject: python make dies :libtk8.5.so: cannot open shared object file: No 
	such file or directory
Message-ID: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>

Trying to build python-2.6.2



./configure --prefix=/usr/local --exec-prefix=/usr/local LDFLAGS="-L/
usr/local"

(runs through happily, had to make some libs local)



make runs most of the way until?



building '_tkinter' extension

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I. -I/tmp/
meld/Python-2.6.2/./Include -I. -IInclude -I./Include -I/usr/local/
include -I/tmp/meld/Python-2.6.2/Include -I/tmp/meld/Python-2.6.2 -c /
tmp/meld/Python-2.6.2/Modules/_tkinter.c -o build/temp.linux-i686-2.6/
tmp/meld/Python-2.6.2/Modules/_tkinter.o

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I. -I/tmp/
meld/Python-2.6.2/./Include -I. -IInclude -I./Include -I/usr/local/
include -I/tmp/meld/Python-2.6.2/Include -I/tmp/meld/Python-2.6.2 -c /
tmp/meld/Python-2.6.2/Modules/tkappinit.c -o build/temp.linux-i686-2.6/
tmp/meld/Python-2.6.2/Modules/tkappinit.o

gcc -pthread -shared build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/
Modules/_tkinter.o build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/
Modules/tkappinit.o -L/usr/X11R6/lib64 -L/usr/X11R6/lib -L/usr/local/
lib -ltk8.5 -ltcl8.5 -lX11 -o build/lib.linux-i686-2.6/_tkinter.so

*** WARNING: renaming "_tkinter" since importing it failed:
libtk8.5.so: cannot open shared object file: No such file or directory



Failed to find the necessary bits to build these modules:

_sqlite3           bsddb185           sunaudiodev

To find the necessary bits, look in setup.py in detect_modules() for
the module's name.





Failed to build these modules:

_tkinter



running build_scripts

# cd /usr/local/lib

# ls -la | grep libtk8.5.so

-r-xr-xr-x   1 root root  1112606 Jul 10 13:28 libtk8.5.so

Am I missing something, it?s there?

Regards,

-Tony


From lists at cheimes.de  Mon Jul 13 10:09:47 2009
From: lists at cheimes.de (Christian Heimes)
Date: Mon, 13 Jul 2009 16:09:47 +0200
Subject: python make dies :libtk8.5.so: cannot open shared object file:
	No    such file or directory
In-Reply-To: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>
References: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>
Message-ID: <h3ff7a$cem$1@ger.gmane.org>

Tony Lay wrote:
> # cd /usr/local/lib
> 
> # ls -la | grep libtk8.5.so
> 
> -r-xr-xr-x   1 root root  1112606 Jul 10 13:28 libtk8.5.so
> 
> Am I missing something, it?s there?

Is /usr/local/lib in your library search path? It looks like it isn't.
Check /etc/ld.so.conf and /etc/ld.so.conf.d/.

Christian



From invalid at invalid  Mon Jul 13 10:16:12 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 13 Jul 2009 09:16:12 -0500
Subject: Problem with two instances of PySerial
References: <a27b2f730907090640od5e09c1g17caf0cdc5b04894@mail.gmail.com>
	<mailman.2932.1247199794.8015.python-list@python.org>
Message-ID: <CbOdnbWQ9_Yx3MbXnZ2dnUVZ_qydnZ2d@posted.visi>


> On Thu, 9 Jul 2009 08:40:18 -0500, Shine Jose <shinejose22 at gmail.com> wrote:

> I achieve this by creating a separate worker thread to poll
> the serial port for arrival of data and then updating the
> required widget in main thread of program. For polling the
> serial port, I create a separate instance of pySerial object.
> However, I am unable to read any data in the worker thread.
> Can the reason for this be 2 instances of pySerial objects
> being connected to serial port.

Yes.

> The reason I had this doubt was because Serial.Connect() in
> the worker thread did not throw any exception & isOpen()
> method returns true.

Under Unix, you are allowed to open a device or file as many
times as you want (there are some common cases where there is a
very useful thing to do).  However, for something like a serial
port, there's only one copy of each received data byte.
Depending on exactly how you structure your code, the incoming
data may be divided up amongst multiple readers, or one
particular reader may get all of it.

-- 
Grant Edwards                   grante             Yow! I joined scientology
                                  at               at a garage sale!!
                               visi.com            


From deets at nospam.web.de  Mon Jul 13 10:17:53 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 13 Jul 2009 16:17:53 +0200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <7c0toaF25751bU1@mid.uni-berlin.de>

seldan24 wrote:

> Hello,
> 
> I'm fairly new at Python so hopefully this question won't be too
> awful.  I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).
> I've figured out two different ways to do this, and am wondering which
> is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
> to understand exactly what occurs for each one.
> 
> The first example:
> 
> from ftplib import FTP
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except Exception, err:
>     print err
> 
> This works fine.  I read through the documentation, and my
> understanding is that there is a built-in exceptions module in python,
> that is automatically available in a built-in namespace.  Within that
> module is an 'Exception' class which would contain whatever exception
> is thrown.  So, I'm passing that to the except, along with err to hold
> the value and then print it out.
> 
> The second example:
> 
> from ftplib import FTP
> import sys
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except:
>     print sys.exc_info()
> 
> Here I, for the most part, get the same thing.  I'm not passing
> anything to except and just printing out the exception using a method
> defined in the sys module.
> 
> So, I'm new to Python... I've made it this far and am happy, but want
> to make sure I'm coding correctly from the start.  Which method is the
> better/cleaner/more standard way to continue?  Thanks for any help.

The latter is - unfortunately - the better. This comes from python allowing
all kinds of objects being thrown as exceptions, not only those extending
from a common ancestor like Exception.

You seem to have a sensible take on this, but anyway I'd like to mention
that using these kinds of catch-all code is rarely justified, as it imposes
the danger of not handling errors at all. So make sure the program spits
out a sensible error-message, and then dies. Unless it's a server-process
of course.

Diez


From invalid at invalid  Mon Jul 13 10:19:29 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 13 Jul 2009 09:19:29 -0500
Subject: need to write a assembly progrm
References: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
	<op.uwup5bama8ncjz@gnudebst> <h393ob$d8u$2@ger.gmane.org>
	<mailman.3037.1247429652.8015.python-list@python.org>
Message-ID: <CbOdnbSQ9_bs38bXnZ2dnUVZ_qydnZ2d@posted.visi>

On 2009-07-12, Rhodri James <rhodri at wildebst.demon.co.uk> wrote:

>> The poorly punctuated paragraph sounds, to me, as if they mean
>> they want (Windows assumed) EXE files that can be dropped onto
>> remote/laptop machines without performing a full installation
>> of Python...
>>
>> But yes... "assembly programs" does, to me, also mean things
>> containing mnemonics for machine level opcodes.
>
> Given that to me, "assembly programs" does not mean .EXE files
> at all, not even a little bit, I'm prefering to refuse to
> guess :-)

Ah, but guessing what a poster meant to ask and then answering
the "guessed" question is a pretty popular sport here in c.l.p.
The discussions resulting from "guessed" questions are often
more informative than the answer to the intended question (if
the OP ever returns to clarify his intent).

-- 
Grant Edwards                   grante             Yow! Bo Derek ruined
                                  at               my life!
                               visi.com            


From tonylay at gmail.com  Mon Jul 13 10:24:08 2009
From: tonylay at gmail.com (Tony Lay)
Date: Mon, 13 Jul 2009 07:24:08 -0700 (PDT)
Subject: python make dies :libtk8.5.so: cannot open shared object file: No
	such file or directory
References: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>
	<mailman.3052.1247494198.8015.python-list@python.org>
Message-ID: <af3033cd-be83-4952-9ddd-5eca139c6283@z28g2000vbl.googlegroups.com>

On Jul 13, 10:09?am, Christian Heimes <li... at cheimes.de> wrote:
> Tony Lay wrote:
> > # cd /usr/local/lib
>
> > # ls -la | grep libtk8.5.so
>
> > -r-xr-xr-x ? 1 root root ?1112606 Jul 10 13:28 libtk8.5.so
>
> > Am I missing something, it?s there?
>
> Is /usr/local/lib in your library search path? It looks like it isn't.
> Check /etc/ld.so.conf and /etc/ld.so.conf.d/.
>
> Christian

I added /usr/local/lib to ld.so.conf.d/python26.conf and ran ldconfig
(thanks Chrisitan)

Ran a make distclean (had to move the files and got a ?file not found?
from my previous working directory).

Everything compiled and installed like a charm.  Thanks!


From python at mrabarnett.plus.com  Mon Jul 13 10:33:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 13 Jul 2009 15:33:42 +0100
Subject: Best Way to Handle All Exceptions
In-Reply-To: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <4A5B45C6.5060404@mrabarnett.plus.com>

seldan24 wrote:
> Hello,
> 
> I'm fairly new at Python so hopefully this question won't be too
> awful.  I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).
> I've figured out two different ways to do this, and am wondering which
> is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
> to understand exactly what occurs for each one.
> 
> The first example:
> 
> from ftplib import FTP
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except Exception, err:
>     print err
> 
> This works fine.  I read through the documentation, and my
> understanding is that there is a built-in exceptions module in python,
> that is automatically available in a built-in namespace.  Within that
> module is an 'Exception' class which would contain whatever exception
> is thrown.  So, I'm passing that to the except, along with err to hold
> the value and then print it out.
> 
There isn't an "exceptions module"; exceptions are part of the language.

> The second example:
> 
> from ftplib import FTP
> import sys
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except:
>     print sys.exc_info()
> 
This is called a "bare exception handler". It's virtually never the
right way to do it.

> Here I, for the most part, get the same thing.  I'm not passing
> anything to except and just printing out the exception using a method
> defined in the sys module.
> 
> So, I'm new to Python... I've made it this far and am happy, but want
> to make sure I'm coding correctly from the start.  Which method is the
> better/cleaner/more standard way to continue?  Thanks for any help.

You should use the most specific exception possible because at lot of
things could raise an exception:

 >>> foo

Traceback (most recent call last):
   File "<pyshell#0>", line 1, in <module>
     foo
NameError: name 'foo' is not defined
 >>> try:
     foo
except Exception, e:
     print "*** Caught an exception ***"
     print e

*** Caught an exception ***
name 'foo' is not defined


From bryanvick at gmail.com  Mon Jul 13 10:52:51 2009
From: bryanvick at gmail.com (Bryan)
Date: Mon, 13 Jul 2009 07:52:51 -0700 (PDT)
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<h383al$pln$1@engnntp2.cig.mot.com>
Message-ID: <cbbcd26b-134b-4d62-9018-a3e12e1e989a@q35g2000vbi.googlegroups.com>

On Jul 10, 12:03?pm, mgi... at motorola.com (Gary Duzan) wrote:
> In article <3af970b1-b454-4d56-a33f-889ecfaca... at l28g2000vba.googlegroups.com>,
>
> Bryan ?<bryanv... at gmail.com> wrote:
>
> >rsyncExec = '/usr/bin/ssh'
> >source = 'r... at 10.0.45.67:/home/bry/jquery.lookup'
> >dest = '/home/bry/tmp'
> >rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> >args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
>
> ? ?I think you want -e and the ssh command to be separate args.
> Something like:
>
> rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
> args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source, dest]
>
> or:
>
> rshArgs = [ '-e', '/usr/bin/ssh -i /home/bry/keys/brybackup.key' ]
> args = [rsyncExec, '-a', '-v', '--dry-run'] + ?rshArgs + [ source, dest]
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Gary Duzan
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Motorola H&NM

Separating the argument parts worked.  Strangely though, I don't need
to do that for arguments such as --files-from='/path/to/file'.  Also,
in this example code I had the rsync executable path pointing to the
ssh program, so no wonder I was getting the output of ssh!


From seldan24 at gmail.com  Mon Jul 13 11:03:27 2009
From: seldan24 at gmail.com (seldan24)
Date: Mon, 13 Jul 2009 08:03:27 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<mailman.3053.1247495610.8015.python-list@python.org>
Message-ID: <d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>

On Jul 13, 10:33?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> seldan24 wrote:
> > Hello,
>
> > I'm fairly new at Python so hopefully this question won't be too
> > awful. ?I am writing some code that will FTP to a host, and want to
> > catch any exception that may occur, take that and print it out
> > (eventually put it into a log file and perform some alerting action).
> > I've figured out two different ways to do this, and am wondering which
> > is the best (i.e. cleanest, 'right' way to proceed). ?I'm also trying
> > to understand exactly what occurs for each one.
>
> > The first example:
>
> > from ftplib import FTP
> > try:
> > ? ? ftp = FTP(ftp_host)
> > ? ? ftp.login(ftp_user, ftp_pass)
> > except Exception, err:
> > ? ? print err
>
> > This works fine. ?I read through the documentation, and my
> > understanding is that there is a built-in exceptions module in python,
> > that is automatically available in a built-in namespace. ?Within that
> > module is an 'Exception' class which would contain whatever exception
> > is thrown. ?So, I'm passing that to the except, along with err to hold
> > the value and then print it out.
>
> There isn't an "exceptions module"; exceptions are part of the language.
>
> > The second example:
>
> > from ftplib import FTP
> > import sys
> > try:
> > ? ? ftp = FTP(ftp_host)
> > ? ? ftp.login(ftp_user, ftp_pass)
> > except:
> > ? ? print sys.exc_info()
>
> This is called a "bare exception handler". It's virtually never the
> right way to do it.
>
> > Here I, for the most part, get the same thing. ?I'm not passing
> > anything to except and just printing out the exception using a method
> > defined in the sys module.
>
> > So, I'm new to Python... I've made it this far and am happy, but want
> > to make sure I'm coding correctly from the start. ?Which method is the
> > better/cleaner/more standard way to continue? ?Thanks for any help.
>
> You should use the most specific exception possible because at lot of
> things could raise an exception:
>
> ?>>> foo
>
> Traceback (most recent call last):
> ? ?File "<pyshell#0>", line 1, in <module>
> ? ? ?foo
> NameError: name 'foo' is not defined
> ?>>> try:
> ? ? ?foo
> except Exception, e:
> ? ? ?print "*** Caught an exception ***"
> ? ? ?print e
>
> *** Caught an exception ***
> name 'foo' is not defined- Hide quoted text -
>
> - Show quoted text -

Thank you both for your input.  I want to make sure I get started on
the right track.  For this particular script, I should have included
that I would take the exception contents, and pass those to the
logging module.  For this particular script, all exceptions are fatal
and I would want them to be.  I just wanted a way to catch them and
log them prior to program termination.  I can understand why folks
should always specify exact exceptions where possible if they plan on
doing something with them, but I just want to log and terminate (and
alarm) when any exception, irregardless of what it is, occurs; that's
why I'm using the catch-all approach.  I most likely should have put
in an exit() in my snippet; sorry about that.

I did notice that Python allows different objects to be thrown.  This
threw me off a bit because, at first, I was expecting everything to
come through as nice, easy tuples.  It turns out that ftplib throws
some class from the sockets module (my terminology may be off here).
As for terminology, sorry about the 'exceptions' misuse.  The Python
documentation refers to 'exceptions' as a module, albeit built-in, so
I used that language accordingly (link to doc:
http://docs.python.org/library/exceptions.html?highlight=exceptions#module-exceptions).

Anyway, thanks again for the help and advice, it is greatly
appreciated.


From floris.bruynooghe at gmail.com  Mon Jul 13 11:13:34 2009
From: floris.bruynooghe at gmail.com (Floris Bruynooghe)
Date: Mon, 13 Jul 2009 08:13:34 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <fb81ece8-4fea-4c55-b585-a95809e3ed32@k20g2000vbp.googlegroups.com>

On Jul 13, 2:26?pm, seldan24 <selda... at gmail.com> wrote:
> The first example:
>
> from ftplib import FTP
> try:
> ? ? ftp = FTP(ftp_host)
> ? ? ftp.login(ftp_user, ftp_pass)
> except Exception, err:
> ? ? print err

*If* you really do want to catch *all* exceptions (as mentioned
already it is usually better to catch specific exceptions) this is the
way to do it.

To know why you should look at the class hierarchy on
http://docs.python.org/library/exceptions.html.  The reason is that
you almost never want to be catching SystemExit, KeyboardInterrupt
etc. catching them will give you trouble at some point (unless you
really know what you're doing but then I would suggest you list them
explicitly instead of using the bare except statement).

While it is true that you could raise an object that is not a subclass
from Exception it is very bad practice, you should never do that.  And
I've haven't seen an external module in the wild that does that in
years and the stdlib will always play nice.


Regards
Floris


From hartley79 at gmail.com  Mon Jul 13 11:47:03 2009
From: hartley79 at gmail.com (hartley)
Date: Mon, 13 Jul 2009 08:47:03 -0700 (PDT)
Subject: Passing python list from C to python
Message-ID: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>

I'm very new at wrapping Python/C, and I have run into some problems.

I have one python module that provides me with a list (provideBuffer
in provideBuff.py):

 Py_Initialize();
	pName = PyString_FromString("provideBuff");
	pModule = PyImport_Import(pName);

	pFunc = PyObject_GetAttrString(pModule,"provideBuffer");

	pValue = PyObject_CallObject(pFunc,NULL);

pValue is now a PyList - i've even verified this with:

int a = PyList_Check(pValue);
	printf("%d\n", a);

However, I want to send this PyList to another python module, but I
don't know how to do this. Initially I though I could just do like
above, only swapping NULL with pValue, but that is not working.

pName2 = PyString_FromString("C-embedding");
pModule2 = PyImport_Import(pName2);
pFunc2 = PyObject_GetAttrString(pModule2,"buff");
pValue2 = PyObject_CallObject(pFunc2,pValue);

pValue2 is now False! So i guess i cannot pass pValue as an argument
to PyObject_CallObject when i want to pass an python list as an
argument. But how must a go about to make this work?


From degibb at gmail.com  Mon Jul 13 12:21:37 2009
From: degibb at gmail.com (David Gibb)
Date: Mon, 13 Jul 2009 12:21:37 -0400
Subject: list of all possible values
Message-ID: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>

Hi guys.

I was thinking about a problem I had: suppose I have a list of
possible values. I want to to have a list of all possible lists of
length n whose values are in that original list.

For example: if my values are ['a', 'b', 'c'], then all possible lists
of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.

I created a recursive program to do it, but I was wondering if there
was a better way of doing it (possibly with list comprehensions).

Here's my recursive version:

vals = ['a', 'b', 'c']

def foo(length):
    if length <=0:
        return []
    if length == 1:
        return [[x] for x in vals]
    else:
        return [x + [y] for x in foo(length - 1) for y in vals]

print foo(3)

Thanks,
David


From bjorn.m.meyer at gmail.com  Mon Jul 13 12:29:56 2009
From: bjorn.m.meyer at gmail.com (Bjorn Meyer)
Date: Mon, 13 Jul 2009 10:29:56 -0600
Subject: multiprocessing and dictionaries
In-Reply-To: <m2y6qt2ezr.fsf@cs.uu.nl>
References: <mailman.3031.1247418982.8015.python-list@python.org>
	<m2y6qt2ezr.fsf@cs.uu.nl>
Message-ID: <200907131029.56346.bjorn.m.meyer@gmail.com>


On Monday 13 July 2009 01:56:08 Piet van Oostrum wrote:

> >>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:
> >
> >BM> I am trying to convert a piece of code that I am using the thread
> > module with BM> to the multiprocessing module.
> >
> >BM> The way that I have it set up is a chunk of code reads a text file and
> > assigns BM> a dictionary key multiple values from the text file. I am
> > using locks to write BM> the values to the dictionary.
> >BM> The way that the values are written is as follows:
> >BM> 	mydict.setdefault(key, []).append(value)
> >
> >BM> The problem that I have run into is that using multiprocessing, the
> > key gets BM> set, but the values don't get appended.
> >BM> I've even tried the Manager().dict() option, but it doesn't seem to
> > work.
> >
> >BM> Is this not supported at this time or am I missing something?
>
> I think you should give more information. Try to make a *minimal* program
> that shows the problem and include it in your posting or supply a
> download link.
> --
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org

Here is what I have been using as a test.
This pretty much mimics what I am trying to do.
I put both threading and multiprocessing in the example which shows the output 
that I am looking for.

#!/usr/bin/env python

import threading
from multiprocessing import Manager, Process

name = ('test1','test2','test3')
data1 = ('dat1','dat2','dat3')
data2 = ('datA','datB','datC')

def thread_test(name,data1,data2, d):
  for nam in name:
    for num in range(0,3):
      d.setdefault(nam, []).append(data1[num])
      d.setdefault(nam, []).append(data2[num])
  print 'Thread test dict:',d

def multiprocess_test(name,data1,data2, mydict):
  for nam in name:
    for num in range(0,3):
      mydict.setdefault(nam, []).append(data1[num])
      mydict.setdefault(nam, []).append(data2[num])
  print 'Multiprocess test dic:',mydict

if __name__ == '__main__':
  mgr = Manager()
  md = mgr.dict()
  d = {}

  m = Process(target=multiprocess_test, args=(name,data1,data2,md))
  m.start()
  t = threading.Thread(target=thread_test, args=(name,data1,data2,d))
  t.start()
  
  m.join()
  t.join()
  
  print 'Thread test:',d
  print 'Multiprocess test:',md


Thanks
Bjorn



From python.list at tim.thechases.com  Mon Jul 13 12:33:20 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Mon, 13 Jul 2009 11:33:20 -0500
Subject: list of all possible values
In-Reply-To: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
References: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
Message-ID: <4A5B61D0.5070403@tim.thechases.com>

> For example: if my values are ['a', 'b', 'c'], then all possible lists
> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
> 
> I created a recursive program to do it, but I was wondering if there
> was a better way of doing it (possibly with list comprehensions).
> 
> Here's my recursive version:
> 
> vals = ['a', 'b', 'c']
> 
> def foo(length):
>     if length <=0:
>         return []
>     if length == 1:
>         return [[x] for x in vals]
>     else:
>         return [x + [y] for x in foo(length - 1) for y in vals]

Sounds like you want one of the combinitoric generators found in 
itertools[1] -- in this case, the itertools.product() does what 
you describe.  According to the docs, it was added in 2.6 so if 
you're running an older version, you'd have to back-port it.

-tkc

[1]
http://docs.python.org/library/itertools.html#itertools.product






From sjmachin at lexicon.net  Mon Jul 13 12:35:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 13 Jul 2009 09:35:16 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
Message-ID: <9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com>

On Jul 14, 1:47?am, hartley <hartle... at gmail.com> wrote:
> I'm very new at wrapping Python/C, and I have run into some problems.
>
> I have one python module that provides me with a list (provideBuffer
> in provideBuff.py):
>
> ?Py_Initialize();
> ? ? ? ? pName = PyString_FromString("provideBuff");
> ? ? ? ? pModule = PyImport_Import(pName);
>
> ? ? ? ? pFunc = PyObject_GetAttrString(pModule,"provideBuffer");
>
> ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> pValue is now a PyList - i've even verified this with:
>
> int a = PyList_Check(pValue);
> ? ? ? ? printf("%d\n", a);
>
> However, I want to send this PyList to another python module,

Please explain "send" ... do you mean the C equivalent of the Python
statement C_embedding.buff = the_pylist ?

BTW C-embedding would trigger a syntax error in Python source; best to
avoid ...

> but I
> don't know how to do this. Initially I though I could just do like
> above, only swapping NULL with pValue, but that is not working.
>
> pName2 = PyString_FromString("C-embedding");
> pModule2 = PyImport_Import(pName2);
> pFunc2 = PyObject_GetAttrString(pModule2,"buff");

Get?? Do you want Set? Is buff a Python function? Or is it the
destination of the "sending"? Any good reason for not checking the
return value for an error? [Rhetorical question; answer == "No"]

> pValue2 = PyObject_CallObject(pFunc2,pValue);

CallObject?? You used this before because you had a function and
wanted to call it because it returned you a value .... now you want to
do one of (in Python terms)

value = amodule.anattr
value = getattr(amodule, "anattr")

or

amodule.anattr = value
setattr(amodule, "anattr", value)


> pValue2 is now False!

False?? Do you mean the C NULL?

> So i guess i cannot pass pValue as an argument
> to PyObject_CallObject when i want to pass an python list as an
> argument. But how must a go about to make this work?

It's mainly just a matter of (1) knowing what you want to do (2)
picking the API that does what you want (3) checking the returned
value for error after every call.

HTH,
John



From bearophileHUGS at lycos.com  Mon Jul 13 12:35:49 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Mon, 13 Jul 2009 09:35:49 -0700 (PDT)
Subject: list of all possible values
References: <mailman.3054.1247502101.8015.python-list@python.org>
Message-ID: <907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>

David Gibb:
> For example: if my values are ['a', 'b', 'c'], then all possible lists
> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.

>>> from itertools import product
>>> list(product("abc", repeat=2))
[('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
'c'), ('c', 'a'), ('c', 'b'), ('c', 'c')]

Bye,
bearophile


From whatnextur at gmail.com  Mon Jul 13 12:50:57 2009
From: whatnextur at gmail.com (whatnext@gmail.com)
Date: Mon, 13 Jul 2009 09:50:57 -0700 (PDT)
Subject: Germany Ups Terrorism Alert Before Election
Message-ID: <cb9150e7-c396-48b6-985f-b0272ca11add@m7g2000prd.googlegroups.com>

With Germany going to the polls in a general election in three months,
authorities are on high alert after detecting an increase in online
warnings of terrorist attacks targeting the country.
The German government held high-level talks with top security and
intelligence chiefs in Berlin on Thursday to discuss the growing
threat posed by Islamic extremists and to coordinate counterterrorism
measures. Intelligence officials are alarmed by the rising number of
videos posted online by militant Islamists who say they are
specifically targeting Germany. Up to 13 videos are reported to have
appeared on the Web since January, many of them referring to the
deployment of German troops in Afghanistan.
(See pictures of U.S. Marines opening a new offensive in Afghanistan.)
for more http://www.terrorismsearch.blogspot.com/


From andreas.tawn at ubisoft.com  Mon Jul 13 12:51:07 2009
From: andreas.tawn at ubisoft.com (Andreas Tawn)
Date: Mon, 13 Jul 2009 18:51:07 +0200
Subject: list of all possible values
In-Reply-To: <907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
References: <mailman.3054.1247502101.8015.python-list@python.org>
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
Message-ID: <8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>

> David Gibb:
> > For example: if my values are ['a', 'b', 'c'], then all possible
lists
> > of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
> 
> >>> from itertools import product
> >>> list(product("abc", repeat=2))
> [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
> 'c'), ('c', 'a'), ('c', 'b'), ('c', 'c')]
> 
> Bye,
> bearophile

Certainly possible with list comprehensions.

>>> a = "abc"
>>> [(x, y) for x in a for y in a]
[('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b', 'c'),
('c', 'a'), ('c', 'b'), ('c', 'c')]

But I like bearophile's version better.

Cheers,

Drea


From gabriel.rossetti at arimaz.com  Mon Jul 13 13:08:12 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Mon, 13 Jul 2009 19:08:12 +0200
Subject: Blocking XMPP API?
In-Reply-To: <h3f6ru$dld$11@lust.ihug.co.nz>
References: <mailman.2893.1247147391.8015.python-list@python.org>
	<h3f6ru$dld$11@lust.ihug.co.nz>
Message-ID: <4A5B69FC.5010109@arimaz.com>

Lawrence D'Oliveiro wrote:
> In message <mailman.2893.1247147391.8015.python-list at python.org>, Gabriel 
> Rossetti wrote:
>
>   
>> I am looking for blocking XMPP API. I'm wanting to make a webservice
>> that uses XMPP, but all the XMPP libs I find are non-blocking (i.e. w/
>> callbacks).
>>     
>
> So why not have the caller sleep or something until the callback is invoked?
>
> It's easier to turn an async API into a synchronous one than the other way 
> round.
>
>   
Yes, that is what I ended up doing, thanks for the response though :-)

Gabriel


From skong1 at gmail.com  Mon Jul 13 13:10:00 2009
From: skong1 at gmail.com (sityee kong)
Date: Mon, 13 Jul 2009 10:10:00 -0700
Subject: Memory error due to big input file
Message-ID: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>

Hi All,

I have a similar problem that many new python users might encounter. I would
really appreciate if you could help me fix the error.
I have a big text file with size more than 2GB. It turned out memory error
when reading in this file. Here is my python script, the error occurred at
line -- self.fh.readlines().

import math
import time

class textfile:
  def __init__(self,fname):
     self.name=fname
     self.fh=open(fname)
     self.fh.readline()
     self.lines=self.fh.readlines()

a=textfile("/home/sservice/nfbc/GenoData/CompareCalls3.diff")

lfile=len(a.lines)

def myfun(snp,start,end):
  subdata=a.lines[start:end+1]
  NEWmiss=0
  OLDmiss=0
  DIFF=0
  for row in subdata:
     k=row.split()
     if (k[3]=="0/0") & (k[4]!="0/0"):
        NEWmiss=NEWmiss+1
     elif (k[3]!="0/0") & (k[4]=="0/0"):
        OLDmiss=OLDmiss+1
     elif (k[3]!="0/0") & (k[4]!="0/0"):
        DIFF=DIFF+1
  result.write(snp+" "+str(NEWmiss)+" "+str(OLDmiss)+" "+str(DIFF)+"\n")

result=open("Summary_noLoop_diff3.txt","w")
result.write("SNP NEWmiss OLDmiss DIFF\n")

start=0
snp=0
for i in range(lfile):
  if (i==0): continue
  after=a.lines[i].split()
  before=a.lines[i-1].split()
  if (before[0]==after[0]):
    if (i!=(lfile-1)): continue
    else:
      end=lfile-1
      myfun(before[0],start,end)
      snp=snp+1
  else:
    end=i-1
    myfun(before[0],start,end)
    snp=snp+1
    start=i
    if (i ==(lfile-1)):
      myfun(after[0],start,start)
      snp=snp+1

result.close()

  sincerely, phoebe
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/79fc0e80/attachment.html>

From skip at pobox.com  Mon Jul 13 13:18:25 2009
From: skip at pobox.com (skip at pobox.com)
Date: Mon, 13 Jul 2009 12:18:25 -0500
Subject: Memory error due to big input file
In-Reply-To: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
Message-ID: <19035.27745.515643.604146@montanaro.dyndns.org>


    phoebe> I have a big text file with size more than 2GB. It turned out
    phoebe> memory error when reading in this file. Here is my python
    phoebe> script, the error occurred at line -- self.fh.readlines().

    phoebe> import math
    phoebe> import time

    phoebe> class textfile:
    phoebe>   def __init__(self,fname):
    phoebe>      self.name=fname
    phoebe>      self.fh=open(fname)
    phoebe>      self.fh.readline()
    phoebe>      self.lines=self.fh.readlines()

Don't do that.  The problem is that you are trying to read the entire file
into memory.  Learn to operate a line (or a few lines) at a time.  Try
something like:

    a = open("/home/sservice/nfbc/GenoData/CompareCalls3.diff")
    for line in a:
        do your per-line work here

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    when i wake up with a heart rate below 40, i head right for the espresso
    machine. -- chaos @ forums.usms.org


From python at mrabarnett.plus.com  Mon Jul 13 13:20:43 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 13 Jul 2009 18:20:43 +0100
Subject: Memory error due to big input file
In-Reply-To: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
Message-ID: <4A5B6CEB.1010507@mrabarnett.plus.com>

sityee kong wrote:
> Hi All,
> 
> I have a similar problem that many new python users might encounter. I 
> would really appreciate if you could help me fix the error.
> I have a big text file with size more than 2GB. It turned out memory 
> error when reading in this file. Here is my python script, the error 
> occurred at line -- self.fh.readlines().
> 
[snip code]
Your 'error' is that you're running it on a computer with insufficient
memory.



From gabriel.rossetti at arimaz.com  Mon Jul 13 13:28:27 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Mon, 13 Jul 2009 19:28:27 +0200
Subject: Threading.Condition problem
In-Reply-To: <m21vom6hla.fsf@cs.uu.nl>
References: <mailman.2957.1247240742.8015.python-list@python.org>
	<m21vom6hla.fsf@cs.uu.nl>
Message-ID: <4A5B6EBB.30906@arimaz.com>


Piet van Oostrum wrote:
>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>             
>
>   
>> GR> Sorry if this appears twice, I sent it once with an attachment and it never
>> GR> arrived so maybe the attachment is posing problems. I inlined the code this
>> GR> time (at the bottom), thank you,
>>     
>
>   
>> GR> Gabriel
>>     
>
>   
>> GR> ########################## Original message ############################
>>     
>
>   
>> GR> Hello everyone,
>>     
>
>   
>> GR> I wrote a small example that listens for xmpp msgs in a thread. The main
>> GR> program calls a function that blocks (using Condition.wait) until a msg
>> GR> has been received and then returns the msg. When a msg arrives, it is
>> GR> put in a variable in the thread's object, it then calls the notify()
>> GR> attr on the Condition object. For some reason, this doesn't work, the
>> GR> thread gets the msg, tries to notify the Condition object, fails because
>> GR> the lock has not been acquired yet and blocks. I tried ignoring the
>> GR> failure, thinking that since it has not been acquired yet then when it
>> GR> is, it will get the msg right away and never call Condition.wait, thus
>> GR> not causing any problems, but this does not work either. Does someone
>> GR> know what I am doing wrong? I attached the code to this msg.
>>     
>
> The code that puts the message in the variable should also acquire the
> lock:
>
>
>      def onMessage(self, conn, msg):
>          with self._cv:
>              self.message = msg
>              self._cv.notify()
>   

Thank you, that was the problem, I eventually found that
> A couple of remarks:
>
> 1. I think the code is neater if all manipulation with the condition is
>    done in the same class (actually in the same instance -- making this
>    instance into a monitor).
>   

The reason I didn't do that is that I don' t want the Listener to sleep, 
I maybe over simplified the example, I actually put them in a dictionary 
as they come in, so in your example, if I have several threads waiting 
on msgs it wouldn't work. I'm trying to make a webservice api thay will 
also be turned into a java .jar for people that need java. Now that I 
think about it, each session will have an instance of the object so msgs 
shouldn' t get mixed up (one connection per user), so I could block in 
the thread. I'll try your suggestion as I think it is cleaner.

> class Listener(Thread):
>     def __init__(self, ws):
>         Thread.__init__(self)
>         self.interrupt = Event()
>         self.message = None
>         self._cv = Condition()
>         self.client = ws._client
>         self.client.RegisterHandler('message', self.onMessage)
>     
>     def onMessage(self, conn, msg):
>         with self._cv:
>             self.message = msg
>             try:
>                 self._cv.notify()
>             except RuntimeError:
>                 print "self._cv has not acquired the lock yet"
>     
>     def getMsg(self):
>         with self._cv:
>             while !self.message
>                 self._cv.wait()
>             return self.message
>
> class WS(object):
>     def __init__(self, username, password, res):
>         self._jid = xmpp.protocol.JID(username)
>         self._client = xmpp.Client(self._jid.getDomain())
> #        self._cv = Condition()
>     
>     def getMsg(self, mid=None):
>         """
>         """
>         return self._listener.getMsg()
>
> Of course I haven't tested this code as I don't have the context
> modules.
>
> 2. I don't know if more than one message can be delivered in the same
>    instance. If yes, than your code will not work, and neither will the
>    code above as, the message instance variable is never cleared. So the
>    next getMsg will be happy to deliver the previous one.
>    You would have to clear it when returning this one.
>     
>   
Like I said above, in reality I have a dict not just a simple variable.
>     def getMsg(self):
>         with self._cv:
>             while !self.message
>                 self._cv.wait()
>             msg = self.message
>             self.message = None
>             return msg
>
> 3. If the messages come in faster than they can be processed some will
>    be lost as they will overwrite the previous one in the self.message
>    variable. The solution is to use a threading.Queue to transfer the
>    messages from one thread to the other. This also saves you the hassle
>    of doing your own synchronisation like above. If you are not familiar
>    with synchronising multithreaded applications it is very easy to make
>    errors and even if you are it is quite easy to do them wrong. I have
>    been involved in distributed programming courses at university level
>    and I have seen many errors in this area.
>   
I used a dict because the API can also be setup to be async and use 
callbacks, so I had to be able to
access the msgs directly and quickly.

Gabriel


From vilya.harvey at gmail.com  Mon Jul 13 13:55:50 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Mon, 13 Jul 2009 18:55:50 +0100
Subject: Best Way to Handle All Exceptions
In-Reply-To: <d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<mailman.3053.1247495610.8015.python-list@python.org>
	<d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>
Message-ID: <6aef848f0907131055p76072a24h68ef2636b9676f50@mail.gmail.com>

2009/7/13 seldan24 <seldan24 at gmail.com>:
> Thank you both for your input. ?I want to make sure I get started on
> the right track. ?For this particular script, I should have included
> that I would take the exception contents, and pass those to the
> logging module. ?For this particular script, all exceptions are fatal
> and I would want them to be. ?I just wanted a way to catch them and
> log them prior to program termination.

The logging module has a function specifically to handle this case:

try:
    # do something
except:
    logging.exception("Uh oh...")

The exception() method will automatically add details of the exception
to the log message it creates; as per the docs, you should only call
it from within an exception handler.

Hope that helps,

Vil.


From emile at fenx.com  Mon Jul 13 13:58:25 2009
From: emile at fenx.com (Emile van Sebille)
Date: Mon, 13 Jul 2009 10:58:25 -0700
Subject: list of all possible values
In-Reply-To: <4A5B61D0.5070403@tim.thechases.com>
References: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
	<4A5B61D0.5070403@tim.thechases.com>
Message-ID: <h3fsjq$p8l$1@ger.gmane.org>

On 7/13/2009 9:33 AM Tim Chase said...
>> For example: if my values are ['a', 'b', 'c'], then all possible lists
>> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
>>
>> I created a recursive program to do it, but I was wondering if there
>> was a better way of doing it (possibly with list comprehensions).
>>
>> Here's my recursive version:
>>
>> vals = ['a', 'b', 'c']
>>
>> def foo(length):
>>     if length <=0:
>>         return []
>>     if length == 1:
>>         return [[x] for x in vals]
>>     else:
>>         return [x + [y] for x in foo(length - 1) for y in vals]
> 
> Sounds like you want one of the combinitoric generators found in 
> itertools[1] -- in this case, the itertools.product() does what you 
> describe.  According to the docs, it was added in 2.6 so if you're 
> running an older version, you'd have to back-port it

Or on systems with list comps try:

 >>> V='abc'
 >>> ['%s%s'%(ii,jj) for ii in V for jj in V]
['aa', 'ab', 'ac', 'ba', 'bb', 'bc', 'ca', 'cb', 'cc']
 >>>

Emile



From mantihor at gmail.com  Mon Jul 13 14:08:39 2009
From: mantihor at gmail.com (Bogdan Opanchuk)
Date: Mon, 13 Jul 2009 11:08:39 -0700 (PDT)
Subject: How to override Marshaller/Unmarshaller in xmlrpc?
Message-ID: <d2a08ca3-f4ce-4df0-a6d6-32aac1bb1d83@l2g2000vba.googlegroups.com>

Is there a way to override marshaller in xmlrpc.client properly? For
example, I want to hide bytes -> Binary transformation inside
marshaller (i.e., just let user pass a bytes value to function and
marshaller dumps it in base64 autmatically). Unfortunately, I cannot
just make a derived class with necessary dump_* function and pass it
to client and server; marshaller initialization seems to be hidden
inside xmlrpc.

So, here's the question - is there a nice way to do it (because there
are some dirty ways like rewriting getparser() ans so on, but I don't
like the idea of copypasting code from library)? Or should I
reconsider my design instead?

Thanks in advance.


From degibb at gmail.com  Mon Jul 13 14:15:24 2009
From: degibb at gmail.com (David Gibb)
Date: Mon, 13 Jul 2009 14:15:24 -0400
Subject: list of all possible values
In-Reply-To: <h3fsjq$p8l$1@ger.gmane.org>
References: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
	<4A5B61D0.5070403@tim.thechases.com> <h3fsjq$p8l$1@ger.gmane.org>
Message-ID: <ef49cad40907131115g4f844d36o6723fa6e46b1d95d@mail.gmail.com>

> Or on systems with list comps try:
>
>>>> V='abc'
>>>> ['%s%s'%(ii,jj) for ii in V for jj in V]
> ['aa', 'ab', 'ac', 'ba', 'bb', 'bc', 'ca', 'cb', 'cc']
>>>>

Yeah, except that the length here is hard-coded. There's no way (as
far as I can tell, at least), to make this generic with respect to
list length.

Thanks for the itertools suggestion, guys. I was hoping to improve my
list-comprehension-fu, but that module was the next best thing.

David

On Mon, Jul 13, 2009 at 1:58 PM, Emile van Sebille<emile at fenx.com> wrote:
> On 7/13/2009 9:33 AM Tim Chase said...
>>>
>>> For example: if my values are ['a', 'b', 'c'], then all possible lists
>>> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
>>>
>>> I created a recursive program to do it, but I was wondering if there
>>> was a better way of doing it (possibly with list comprehensions).
>>>
>>> Here's my recursive version:
>>>
>>> vals = ['a', 'b', 'c']
>>>
>>> def foo(length):
>>> ? ?if length <=0:
>>> ? ? ? ?return []
>>> ? ?if length == 1:
>>> ? ? ? ?return [[x] for x in vals]
>>> ? ?else:
>>> ? ? ? ?return [x + [y] for x in foo(length - 1) for y in vals]
>>
>> Sounds like you want one of the combinitoric generators found in
>> itertools[1] -- in this case, the itertools.product() does what you
>> describe. ?According to the docs, it was added in 2.6 so if you're running
>> an older version, you'd have to back-port it
>

>
> Emile
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From darkwater42 at gmail.com  Mon Jul 13 14:19:59 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Mon, 13 Jul 2009 11:19:59 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
Message-ID: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>

I couldn't find a good algorithms forum on the Internet, so I guess
I'll ask this question here instead: Is it possible to efficiently
maintain a binary search tree in a flat array (i.e., without using
pointers), as is typically done for a binary heap?

It *is* possible, of course, to keep an ordered list in a flat array,
and then do a binary search on the ordered array, but then insertion
and deletion are O(n), rather than O(log n). It would also clearly be
possible to store a balanced binary tree in a flat array, storing the
children of the node at index i at indices 2*i and 2*i + 1, just as
one does for a binary heap. But if you do that, I don't know if you
could then do insertions and deletions in O(log n) time.

One idea that came to mind, is that maybe it is possible using a
"treap", which is a combination of a binary heap and a binary search
tree. Insertions and deletions in binary heaps can be done in O(log n)
in a flat array, but I don't know if this is also true for a treap,
since you also have the binary search tree invariants to maintain, in
addition to the binary heap invariants. For all I know, this might
cause rotations to no longer be O(log n).

|>ouglas


From piet at cs.uu.nl  Mon Jul 13 14:25:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 20:25:58 +0200
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<h383al$pln$1@engnntp2.cig.mot.com>
	<cbbcd26b-134b-4d62-9018-a3e12e1e989a@q35g2000vbi.googlegroups.com>
Message-ID: <m2ocro1lu1.fsf@cs.uu.nl>

>>>>> Bryan <bryanvick at gmail.com> (B) wrote:

>B> On Jul 10, 12:03?pm, mgi... at motorola.com (Gary Duzan) wrote:
>>> In article <3af970b1-b454-4d56-a33f-889ecfaca... at l28g2000vba.googlegroups.com>,
>>> 
>>> Bryan ?<bryanv... at gmail.com> wrote:
>>> 
>>> >rsyncExec = '/usr/bin/ssh'
>>> >source = 'r... at 10.0.45.67:/home/bry/jquery.lookup'
>>> >dest = '/home/bry/tmp'
>>> >rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>> >args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
>>> 
>>> ? ?I think you want -e and the ssh command to be separate args.
>>> Something like:
>>> 
>>> rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
>>> args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source, dest]
>>> 
>>> or:
>>> 
>>> rshArgs = [ '-e', '/usr/bin/ssh -i /home/bry/keys/brybackup.key' ]
>>> args = [rsyncExec, '-a', '-v', '--dry-run'] + ?rshArgs + [ source, dest]
>>> 
>>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Gary Duzan
>>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Motorola H&NM

>B> Separating the argument parts worked.  Strangely though, I don't need
>B> to do that for arguments such as --files-from='/path/to/file'.  Also,
>B> in this example code I had the rsync executable path pointing to the
>B> ssh program, so no wonder I was getting the output of ssh!

I should have seen that because I changed it in my own copy!!!

--files-from='/path/to/file *is* one argument, in contrast to 
-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key" which is two
arguments.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 14:33:17 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 20:33:17 +0200
Subject: Threading.Condition problem
References: <mailman.2957.1247240742.8015.python-list@python.org>
	<m21vom6hla.fsf@cs.uu.nl>
	<mailman.3061.1247506110.8015.python-list@python.org>
Message-ID: <m2k52c1lhu.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Piet van Oostrum wrote:
...
>GR> I wrote a small example that listens for xmpp msgs in a thread. The main
>GR> program calls a function that blocks (using Condition.wait) until a msg
>GR> has been received and then returns the msg. When a msg arrives, it is
>GR> put in a variable in the thread's object, it then calls the notify()
>GR> attr on the Condition object. For some reason, this doesn't work, the
>GR> thread gets the msg, tries to notify the Condition object, fails because
>GR> the lock has not been acquired yet and blocks. I tried ignoring the
>GR> failure, thinking that since it has not been acquired yet then when it
>GR> is, it will get the msg right away and never call Condition.wait, thus
>GR> not causing any problems, but this does not work either. Does someone
>GR> know what I am doing wrong? I attached the code to this msg.
>>>> 
>>> 
>>> The code that puts the message in the variable should also acquire the
>>> lock:
>>> 
>>> 
>>> def onMessage(self, conn, msg):
>>> with self._cv:
>>> self.message = msg
>>> self._cv.notify()
>>> 

>GR> Thank you, that was the problem, I eventually found that
>>> A couple of remarks:
>>> 
>>> 1. I think the code is neater if all manipulation with the condition is
>>> done in the same class (actually in the same instance -- making this
>>> instance into a monitor).
>>> 

>GR> The reason I didn't do that is that I don' t want the Listener to sleep, I
>GR> maybe over simplified the example, I actually put them in a dictionary as
>GR> they come in, so in your example, if I have several threads waiting on msgs
>GR> it wouldn't work. I'm trying to make a webservice api thay will also be
>GR> turned into a java .jar for people that need java. Now that I think about
>GR> it, each session will have an instance of the object so msgs shouldn' t get
>GR> mixed up (one connection per user), so I could block in the thread. I'll
>GR> try your suggestion as I think it is cleaner.

Sleeping as you call it is better than busy waiting. You must have some
synchronisation to make it efficient.
If you put the messages in a dictionary access to the dictionary must be
protected. Having several threads waiting for the messages doesn't
prevent you from using proper synchronisation. Maybe you must use
notify_all instead of notify.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From http  Mon Jul 13 14:55:34 2009
From: http (Paul Rubin)
Date: 13 Jul 2009 11:55:34 -0700
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
Message-ID: <7x7hycmmzd.fsf@ruckus.brouhaha.com>

Douglas Alan <darkwater42 at gmail.com> writes:
> It would also clearly be
> possible to store a balanced binary tree in a flat array, storing the
> children of the node at index i at indices 2*i and 2*i + 1, just as
> one does for a binary heap. But if you do that, I don't know if you
> could then do insertions and deletions in O(log n) time.

Probably not.  Maybe you could organize a 2-3 tree like that, at the
expense of some space.


From piet at cs.uu.nl  Mon Jul 13 15:12:18 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 21:12:18 +0200
Subject: multiprocessing and dictionaries
References: <mailman.3031.1247418982.8015.python-list@python.org>
	<m2y6qt2ezr.fsf@cs.uu.nl>
	<mailman.3056.1247503227.8015.python-list@python.org>
Message-ID: <m2ab381jot.fsf@cs.uu.nl>

>>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:

>BM> Here is what I have been using as a test.
>BM> This pretty much mimics what I am trying to do.
>BM> I put both threading and multiprocessing in the example which shows
>BM> the output that I am looking for.

>BM> #!/usr/bin/env python

>BM> import threading
>BM> from multiprocessing import Manager, Process

>BM> name = ('test1','test2','test3')
>BM> data1 = ('dat1','dat2','dat3')
>BM> data2 = ('datA','datB','datC')

[snip]

>BM> def multiprocess_test(name,data1,data2, mydict):
>BM>   for nam in name:
>BM>     for num in range(0,3):
>BM>       mydict.setdefault(nam, []).append(data1[num])
>BM>       mydict.setdefault(nam, []).append(data2[num])
>BM>   print 'Multiprocess test dic:',mydict

I guess what's happening is this:

d.setdefault(nam, []) returns a list, initially an empty list ([]). This
list gets appended to. However, this list is a local list in the
multi-process_test Process, therefore the result is not reflected in the
original list inside the manager. Therefore all your updates get lost.
You will have to do operations directly on the dictionary itself, not on
any intermediary objects. Of course with the threading the situation is
different as all operations are local.

This works:

def multiprocess_test(name,data1,data2, mydict):
  print name, data1, data2
  for nam in name:
    for num in range(0,3):
      mydict.setdefault(nam, [])
      mydict[nam] += [data1[num]]
      mydict[nam] += [data2[num]]
  print 'Multiprocess test dic:',mydict

If you have more than one process operating on the dictionary
simultaneously you have to beware of race conditions!!
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 15:31:28 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 21:31:28 +0200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <m263dw1isv.fsf@cs.uu.nl>

>>>>> seldan24 <seldan24 at gmail.com> (s) wrote:

>s> Hello,
>s> I'm fairly new at Python so hopefully this question won't be too
>s> awful.  I am writing some code that will FTP to a host, and want to
>s> catch any exception that may occur, take that and print it out
>s> (eventually put it into a log file and perform some alerting action).
>s> I've figured out two different ways to do this, and am wondering which
>s> is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
>s> to understand exactly what occurs for each one.

>s> The first example:

>s> from ftplib import FTP
>s> try:
>s>     ftp = FTP(ftp_host)
>s>     ftp.login(ftp_user, ftp_pass)
>s> except Exception, err:
>s>     print err

I think you should restrict yourself to those exceptions that are
related to ftp. Do you want to catch an exception like a misspelling in
one of the variables?

from ftplib import FTP, all_errors

try:
    ftp = FTP(ftp_host)
    ftp.login(ftp_user, ftp_pass)
except all_errors, err:
    print err

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Mon Jul 13 15:57:38 2009
From: aahz at pythoncraft.com (Aahz)
Date: 13 Jul 2009 12:57:38 -0700
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
Message-ID: <h3g3ji$p90$1@panix3.panix.com>

In article <ae6c3191-1167-43eb-9d36-23c7c49b5876 at l28g2000vba.googlegroups.com>,
Douglas Alan  <darkwater42 at gmail.com> wrote:
>
>I couldn't find a good algorithms forum on the Internet, so I guess
>I'll ask this question here instead: Is it possible to efficiently
>maintain a binary search tree in a flat array (i.e., without using
>pointers), as is typically done for a binary heap?
>
>It *is* possible, of course, to keep an ordered list in a flat array,
>and then do a binary search on the ordered array, but then insertion
>and deletion are O(n), rather than O(log n). 

Still, unless your list is large (more than thousands of elements),
that's the way you should go.  See the bisect module.  Thing is, the
speed difference between C and Python means the constant for insertion
and deletion is very very small relative to bytecode speed.  Keep in
mind that Python's object/binding model means that you're shuffling
pointers in the list rather than items.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From newport at freemail.hu  Mon Jul 13 16:17:31 2009
From: newport at freemail.hu (Andras Szabo)
Date: Mon, 13 Jul 2009 23:17:31 +0300
Subject: Tkinter / Entry widget problem
Message-ID: <E68CFAD0-A09B-4B2B-9E38-2EFD758BE685@freemail.hu>

Hello. I searched the archives but couldn't find a solution to a  
problem related to the Entry widget in Tkinter.

When creating a pop-up window in an app, which contains an Entry  
widget, I want this widget to contain some default string, to have all  
this default string selected (as if the user had manually selected  
everything), and to have the focus transferred to this widget.

(The idea is then that if the window pops up, the user won't have to  
click or press Tab any more before being able to type what is needed  
in the textbox, overwriting what is written there already.)

I thought this might be the way to go:

entrybox=Entry(toplevel_parent_window)
entrybox.insert(0,"Some default string")
entrybox.select_range(0,END)
entrybox.focus_set()
entrybox.pack()

But it doesn't seem to work - the focus is not transferred to the  
Entry widget, and the text does not appear to be selected (even though  
after this entrybox.selection_present() returns True).

What am I doing wrong?

andras


From tjreedy at udel.edu  Mon Jul 13 16:19:14 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 13 Jul 2009 16:19:14 -0400
Subject: Best Way to Handle All Exceptions
In-Reply-To: <7c0toaF25751bU1@mid.uni-berlin.de>
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<7c0toaF25751bU1@mid.uni-berlin.de>
Message-ID: <h3g4rv$k0s$1@ger.gmane.org>

Diez B. Roggisch wrote:

> The latter is - unfortunately - the better. This comes from python allowing
> all kinds of objects being thrown as exceptions, not only those extending
> from a common ancestor like Exception.

Fixed in Python 3. exceptions, without exceptions, are instances of 
BaseException, either directly or as instances of subcleasses of 
BaseException.

One of many reasons to switch when possible.
tjr



From darkwater42 at gmail.com  Mon Jul 13 16:47:19 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Mon, 13 Jul 2009 13:47:19 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
Message-ID: <5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>

On Jul 13, 3:57?pm, a... at pythoncraft.com (Aahz) wrote:

> Still, unless your list is large (more than thousands of elements),
> that's the way you should go. ?See the bisect module. ?Thing is, the
> speed difference between C and Python means the constant for insertion
> and deletion is very very small relative to bytecode speed. ?Keep in
> mind that Python's object/binding model means that you're shuffling
> pointers in the list rather than items.

Thank you. My question wasn't intended to be Python specific, though.
I am just curious for purely academic reasons about whether there is
such an algorithm. All the sources I've skimmed only seem to the
answer the question via omission. Which is kind of strange, since it
seems to me like an obvious question to ask.

If I find the free time, I might try to work out myself whether it can
be done with a treap.

|>ouglas


From davea at ieee.org  Mon Jul 13 17:01:17 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 13 Jul 2009 17:01:17 -0400
Subject: Memory error due to big input file
In-Reply-To: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
Message-ID: <4A5BA09D.9070402@ieee.org>

sityee kong wrote:
> Hi All,
>
> I have a similar problem that many new python users might encounter. I would
> really appreciate if you could help me fix the error.
> I have a big text file with size more than 2GB. It turned out memory error
> when reading in this file. Here is my python script, the error occurred at
> line -- self.fh.readlines().
>
> import math
> import time
>
> class textfile:
>   def __init__(self,fname):
>      self.name=fname
>      self.fh=open(fname)
>      self.fh.readline()
>      self.lines=self.fh.readlines()
>
> a=textfile("/home/sservice/nfbc/GenoData/CompareCalls3.diff")
>
> lfile=len(a.lines)
>
> def myfun(snp,start,end):
>   subdata=a.lines[start:end+1]
>   NEWmiss=0
>   OLDmiss=0
>   DIFF=0
>   for row in subdata:
>      k=row.split()
>      if (k[3]=="0/0") & (k[4]!="0/0"):
>         NEWmiss=NEWmiss+1
>      elif (k[3]!="0/0") & (k[4]=="0/0"):
>         OLDmiss=OLDmiss+1
>      elif (k[3]!="0/0") & (k[4]!="0/0"):
>         DIFF=DIFF+1
>   result.write(snp+" "+str(NEWmiss)+" "+str(OLDmiss)+" "+str(DIFF)+"\n")
>
> result=open("Summary_noLoop_diff3.txt","w")
> result.write("SNP NEWmiss OLDmiss DIFF\n")
>
> start=0
> snp=0
> for i in range(lfile):
>   if (i==0): continue
>   after=a.lines[i].split()
>   before=a.lines[i-1].split()
>   if (before[0]==after[0]):
>     if (i!=(lfile-1)): continue
>     else:
>       end=lfile-1
>       myfun(before[0],start,end)
>       snp=snp+1
>   else:
>     end=i-1
>     myfun(before[0],start,end)
>     snp=snp+1
>     start=i
>     if (i ==(lfile-1)):
>       myfun(after[0],start,start)
>       snp=snp+1
>
> result.close()
>
>   sincerely, phoebe
>
>   
Others have pointed out that you have too little memory for a 2gig data 
structure.  If you're running on a 32bit system, chances are it won't 
matter how much memory you add, a process is limited to 4gb, and the OS 
typically takes about half of it, your code and other data takes some, 
and you don't have 2gig left.   A 64 bit version of Python, running on a 
64bit OS, might be able to "just work."

Anyway, loading the whole file into a list is seldom the best answer, 
except for files under a meg or so.  It's usually better to process the 
file in sequence.  It looks like you're also making slices of that data, 
so they could potentially be pretty big as well.

If you can be assured that you only need the current line and the 
previous two (for example), then you can use a list of just those three, 
and delete the oldest one, and add a new one to that list each time 
through the loop.

Or, you can add some methods to that 'textfile' class that fetch a line 
by index.  Brute force, you could pre-scan the file, and record all the 
file offsets for the lines you find, rather than storing the actual 
line.  So you still have just as big a list, but it's a list of 
integers.  Then when somebody calls your method, he passes an integer, 
and you return the particular line.  A little caching for performance, 
and you're good to go.

Anyway, if you organize it that way, you can code the rest of the module 
to not care whether the whole file is really in memory or not.

BTW, you should derive all your classes from something.  If nothing 
else, use object.
  class textfile(object):




From aaron.hildebrandt at gmail.com  Mon Jul 13 17:14:27 2009
From: aaron.hildebrandt at gmail.com (Aaron Scott)
Date: Mon, 13 Jul 2009 14:14:27 -0700 (PDT)
Subject: Pickling classes -- disappearing lists?
Message-ID: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>

I'm trying to pickle an instance of a class. It mostly works just fine
-- I can save the pickle to a file, restore it from that file, and
it's mostly okay. The problem is, some lists seem to disappear. For
example (snipped and crunched from the code giving me trouble):

---


class InitGame:
	value = False
	journal = []


game.InitGame()


def Save():
	global game
	import cPickle, gzip, os

	# Change some data
	game.journal.append("A value")
	game.value = True

	pickles = {'game': game}
	jar = gzip.open("pickefile", 'wb')
	cPickle.dump(pickles, jar, 2)
	jar.close()


def Load():
	global game
	import gzip, os, cPickle
	jar = gzip.open("picklefile", 'r')
	loaded = cPickle.load(jar)
	jar.close()
	game = loaded["game"]


---

Now, if I save a pickle, then load it back in, I'll get an instance of
InitGame called "game", and game.value will be true, but the list
"journal" will be empty.

Am I missing something obvious about the pickle spec? Am I doing
something wrong? Or should I be hunting for a deeper bug in the code?
I've noticed that pretty much anything that's a list isn't saving to
the pickle (or loading from the pickle... it's hard to tell which).


From aaron.hildebrandt at gmail.com  Mon Jul 13 17:20:13 2009
From: aaron.hildebrandt at gmail.com (Aaron Scott)
Date: Mon, 13 Jul 2009 14:20:13 -0700 (PDT)
Subject: Memory error due to big input file
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com> 
	<mailman.3067.1247518893.8015.python-list@python.org>
Message-ID: <4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>

> BTW, you should derive all your classes from something. ?If nothing
> else, use object.
> ? class textfile(object):

Just out of curiousity... why is that? I've been coding in Python for
a long time, and I never derive my base classes. What's the advantage
to deriving them?


From l.lensgraf at gmail.com  Mon Jul 13 17:44:44 2009
From: l.lensgraf at gmail.com (DrLeif)
Date: Mon, 13 Jul 2009 14:44:44 -0700 (PDT)
Subject: PDF: finding a blank image
Message-ID: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>

I have about 6000 PDF files which have been produced using a scanner
with more being produced each day.  The PDF files contain old paper
records which have been taking up space.   The scanner is set to
detect when there is information on the backside of the page (duplex
scan).  The problem of course is it's not the always reliable and we
wind up with a number of PDF files containing blank pages.

What I would like to do is have python detect a "blank" pages in a PDF
file and remove it.  Any suggestions?


Thanks,
DrL


From clp2 at rebertia.com  Mon Jul 13 17:50:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 14:50:23 -0700
Subject: Pickling classes -- disappearing lists?
In-Reply-To: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>
References: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>
Message-ID: <50697b2c0907131450j5d3f9799l2e9c206b3c749f39@mail.gmail.com>

On Mon, Jul 13, 2009 at 2:14 PM, Aaron Scott<aaron.hildebrandt at gmail.com> wrote:
> I'm trying to pickle an instance of a class. It mostly works just fine
> -- I can save the pickle to a file, restore it from that file, and
> it's mostly okay. The problem is, some lists seem to disappear. For
> example (snipped and crunched from the code giving me trouble):
>
> ---
>
>
> class InitGame:
> ? ? ? ?value = False
> ? ? ? ?journal = []
>
>
> game.InitGame()

That line doesn't make sense with the code you've given...

> def Save():
> ? ? ? ?global game
> ? ? ? ?import cPickle, gzip, os
>
> ? ? ? ?# Change some data
> ? ? ? ?game.journal.append("A value")
> ? ? ? ?game.value = True
>
> ? ? ? ?pickles = {'game': game}
> ? ? ? ?jar = gzip.open("pickefile", 'wb')
> ? ? ? ?cPickle.dump(pickles, jar, 2)
> ? ? ? ?jar.close()
>
>
> def Load():
> ? ? ? ?global game
> ? ? ? ?import gzip, os, cPickle
> ? ? ? ?jar = gzip.open("picklefile", 'r')
> ? ? ? ?loaded = cPickle.load(jar)
> ? ? ? ?jar.close()
> ? ? ? ?game = loaded["game"]
>
>
> ---
>
> Now, if I save a pickle, then load it back in, I'll get an instance of
> InitGame called "game", and game.value will be true, but the list
> "journal" will be empty.
>
> Am I missing something obvious about the pickle spec? Am I doing
> something wrong? Or should I be hunting for a deeper bug in the code?

Your class definition isn't right. It makes 'value' and 'journal'
class variables (Java lingo: "static variables") as opposed to the
instance variables they should be. Here's a corrected version:

class InitGame(object):
    def __init__(self):
        #instance variables are created through self.foo assignments in __init__
        self.value = False
        self.journal = []

Cheers,
Chris
--
http://blog.rebertia.com


From vilya.harvey at gmail.com  Mon Jul 13 17:51:01 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Mon, 13 Jul 2009 22:51:01 +0100
Subject: Memory error due to big input file
In-Reply-To: <4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
	<mailman.3067.1247518893.8015.python-list@python.org>
	<4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
Message-ID: <6aef848f0907131451h2ae1b83cs1eda1651e6db13@mail.gmail.com>

2009/7/13 Aaron Scott <aaron.hildebrandt at gmail.com>:
>> BTW, you should derive all your classes from something. ?If nothing
>> else, use object.
>> ? class textfile(object):
>
> Just out of curiousity... why is that? I've been coding in Python for
> a long time, and I never derive my base classes. What's the advantage
> to deriving them?

    class Foo:

uses the old object model.

    class Foo(object):

uses the new object model.

See http://docs.python.org/reference/datamodel.html (specifically
section 3.3) for details of the differences.

Vil.


From clp2 at rebertia.com  Mon Jul 13 18:02:37 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 15:02:37 -0700
Subject: Memory error due to big input file
In-Reply-To: <6aef848f0907131451h2ae1b83cs1eda1651e6db13@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
	<mailman.3067.1247518893.8015.python-list@python.org>
	<4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
	<6aef848f0907131451h2ae1b83cs1eda1651e6db13@mail.gmail.com>
Message-ID: <50697b2c0907131502p2e262a22p4a6af5a31bfee677@mail.gmail.com>

On Mon, Jul 13, 2009 at 2:51 PM, Vilya Harvey<vilya.harvey at gmail.com> wrote:
> 2009/7/13 Aaron Scott <aaron.hildebrandt at gmail.com>:
>>> BTW, you should derive all your classes from something. ?If nothing
>>> else, use object.
>>> ? class textfile(object):
>>
>> Just out of curiousity... why is that? I've been coding in Python for
>> a long time, and I never derive my base classes. What's the advantage
>> to deriving them?
>
> ? ?class Foo:
>
> uses the old object model.
>
> ? ?class Foo(object):
>
> uses the new object model.
>
> See http://docs.python.org/reference/datamodel.html (specifically
> section 3.3) for details of the differences.

Note that Python 3.0 makes explicitly subclassing `object` unnecessary
since it removes old-style classes; a class that doesn't explicitly
subclass anything will implicitly subclass `object`.

Cheers,
Chris
-- 
http://blog.rebertia.com


From aaron.hildebrandt at gmail.com  Mon Jul 13 19:00:18 2009
From: aaron.hildebrandt at gmail.com (Aaron Scott)
Date: Mon, 13 Jul 2009 16:00:18 -0700 (PDT)
Subject: Pickling classes -- disappearing lists?
References: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>
	<mailman.3068.1247521826.8015.python-list@python.org>
Message-ID: <60e9b0e3-25c7-4d01-a120-b15b33a06b57@m18g2000vbi.googlegroups.com>

> Your class definition isn't right. It makes 'value' and 'journal'
> class variables (Java lingo: "static variables") as opposed to the
> instance variables they should be. Here's a corrected version:
>

Woah, thanks. I can't believe I made such a stupid mistake. It's not
like I'm a newcomer to Python, either. I'm can't believe I never
noticed what I was doing.

No more 2am coding for me.

Thanks,
Aaron


From db3l.net at gmail.com  Mon Jul 13 19:05:05 2009
From: db3l.net at gmail.com (David Bolen)
Date: Mon, 13 Jul 2009 19:05:05 -0400
Subject: PDF: finding a blank image
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
Message-ID: <m2tz1gdw0u.fsf@valheru.db3l.homeip.net>

DrLeif <l.lensgraf at gmail.com> writes:

> What I would like to do is have python detect a "blank" pages in a PDF
> file and remove it.  Any suggestions?

The odds are good that even a blank page is being "rendered" within
the PDF as having some small bits of data due to scanner resolution,
imperfections on the page, etc..  So I suspect you won't be able to just
look for a well-defined pattern in the resulting PDF or anything.

Unless you're using OCR, the odds are good that the scanner is
rendering the PDF as an embedded image.  What I'd probably do is
extract the image of the page, and then use image processing on it to
try to identify blank pages.  I haven't had the need to do this
myself, and tool availability would depend on platform, but for
example, I'd probably try ImageMagick's convert operation to turn the
PDF into images (like PNGs).  I think Gimp can also do a similar
conversion, but you'd probably have to script it yourself.

Once you have an image of a page, you could then use something like
OpenCV to process the page (perhaps a morphology operation to remove
small noise areas, then a threshold or non-zero counter to judge
"blankness"), or probably just something like PIL depending on
complexity of the processing needed.

Once you identify a blank page, removing it could either be with pure
Python (there have been other posts recently about PDF libraries) or
with external tools (such as pdftk under Linux for example).

-- David


From Scott.Daniels at Acm.Org  Mon Jul 13 19:22:23 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 13 Jul 2009 16:22:23 -0700
Subject: PDF: finding a blank image
In-Reply-To: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
Message-ID: <h7udnSUJcYlyIsbXnZ2dnUVZ_vWdnZ2d@pdx.net>

DrLeif wrote:
> I have about 6000 PDF files which have been produced using a scanner
> with more being produced each day.  The PDF files contain old paper
> records which have been taking up space.   The scanner is set to
> detect when there is information on the backside of the page (duplex
> scan).  The problem of course is it's not the always reliable and we
> wind up with a number of PDF files containing blank pages.
> 
> What I would like to do is have python detect a "blank" pages in a PDF
> file and remove it.  Any suggestions?

I'd check into ReportLab's commercial product, it may well be easily
capable of that.  If no success, you might contact PJ at Groklaw, she
has dealt with a _lot_ of PDFs (and knows people who deal with PDFs
in bulk).

--Scott David Daniels
Scott.Daniels at Acm.Org


From Brian.Mingus at colorado.edu  Mon Jul 13 19:26:26 2009
From: Brian.Mingus at colorado.edu (Brian)
Date: Mon, 13 Jul 2009 17:26:26 -0600
Subject: PDF: finding a blank image
In-Reply-To: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
Message-ID: <9839a05c0907131626w77489e62raf1582a9ff429a8f@mail.gmail.com>

Perhaps your blank pages have a characteristic size. Or perhaps if you trim
them with `convert' (ImageMagick) there is nothing left.

On Mon, Jul 13, 2009 at 3:44 PM, DrLeif <l.lensgraf at gmail.com> wrote:

> I have about 6000 PDF files which have been produced using a scanner
> with more being produced each day.  The PDF files contain old paper
> records which have been taking up space.   The scanner is set to
> detect when there is information on the backside of the page (duplex
> scan).  The problem of course is it's not the always reliable and we
> wind up with a number of PDF files containing blank pages.
>
> What I would like to do is have python detect a "blank" pages in a PDF
> file and remove it.  Any suggestions?
>
>
> Thanks,
> DrL
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/170847bf/attachment.html>

From bjorn.m.meyer at gmail.com  Mon Jul 13 19:35:00 2009
From: bjorn.m.meyer at gmail.com (Bjorn Meyer)
Date: Mon, 13 Jul 2009 17:35:00 -0600
Subject: multiprocessing and dictionaries
In-Reply-To: <m2ab381jot.fsf@cs.uu.nl>
References: <mailman.3031.1247418982.8015.python-list@python.org>
	<mailman.3056.1247503227.8015.python-list@python.org>
	<m2ab381jot.fsf@cs.uu.nl>
Message-ID: <200907131735.00191.bjorn.m.meyer@gmail.com>


On Monday 13 July 2009 13:12:18 Piet van Oostrum wrote:

> >>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:
> >
> >BM> Here is what I have been using as a test.
> >BM> This pretty much mimics what I am trying to do.
> >BM> I put both threading and multiprocessing in the example which shows
> >BM> the output that I am looking for.
> >
> >BM> #!/usr/bin/env python
> >
> >BM> import threading
> >BM> from multiprocessing import Manager, Process
> >
> >BM> name = ('test1','test2','test3')
> >BM> data1 = ('dat1','dat2','dat3')
> >BM> data2 = ('datA','datB','datC')
>
> [snip]
>
> >BM> def multiprocess_test(name,data1,data2, mydict):
> >BM>   for nam in name:
> >BM>     for num in range(0,3):
> >BM>       mydict.setdefault(nam, []).append(data1[num])
> >BM>       mydict.setdefault(nam, []).append(data2[num])
> >BM>   print 'Multiprocess test dic:',mydict
>
> I guess what's happening is this:
>
> d.setdefault(nam, []) returns a list, initially an empty list ([]). This
> list gets appended to. However, this list is a local list in the
> multi-process_test Process, therefore the result is not reflected in the
> original list inside the manager. Therefore all your updates get lost.
> You will have to do operations directly on the dictionary itself, not on
> any intermediary objects. Of course with the threading the situation is
> different as all operations are local.
>
> This works:
>
> def multiprocess_test(name,data1,data2, mydict):
>   print name, data1, data2
>   for nam in name:
>     for num in range(0,3):
>       mydict.setdefault(nam, [])
>       mydict[nam] += [data1[num]]
>       mydict[nam] += [data2[num]]
>   print 'Multiprocess test dic:',mydict
>
> If you have more than one process operating on the dictionary
> simultaneously you have to beware of race conditions!!
> --
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org

Excellent. That works perfectly.

Thank you for your response Piet.

Bjorn




From ben+python at benfinney.id.au  Mon Jul 13 20:09:06 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 14 Jul 2009 10:09:06 +1000
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <87eiskktwd.fsf@benfinney.id.au>

seldan24 <seldan24 at gmail.com> writes:

> I'm fairly new at Python so hopefully this question won't be too
> awful.  I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).

You have been given a lot of advice so far about catching exceptions
with the ?try ? except? syntax. But reading your request, I think
perhaps you don't want to catch exceptions at all.

Instead of catching *all* exceptions at a specific point in your code,
and then having nothing to do but end the program (possibly after some
pre-exit action like logging), I think you would be better served by
installing a custom top-level exception handler.

    When an exception is raised and uncaught, the interpreter calls
    sys.excepthook with three arguments, the exception class, exception
    instance, and a traceback object. In an interactive session this
    happens just before control is returned to the prompt; in a Python
    program this happens just before the program exits. The handling of
    such top-level exceptions can be customized by assigning another
    three-argument function to sys.excepthook.

    <URL:http://docs.python.org/library/sys#sys.excepthook>

With a custom top-level exception handler in place, you should then
restrict your use of ?try: ? except FooException: ?? to be as precise
as possible, so that the ?try? block is as small as possible and the
?FooException? is as specific as possible.

Any other exceptions that you don't specifically catch will then go
through to your default handle-it-just-before-we-exit ?sys.excepthook?
exception handler.

-- 
 \         ?Nature hath given men one tongue but two ears, that we may |
  `\          hear from others twice as much as we speak.? ?Epictetus, |
_o__)                                                      _Fragments_ |
Ben Finney


From pavlovevidence at gmail.com  Mon Jul 13 20:49:23 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 13 Jul 2009 17:49:23 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
Message-ID: <4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>

On Jul 13, 12:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> seldan24 <selda... at gmail.com> (s) wrote:
> >s> Hello,
> >s> I'm fairly new at Python so hopefully this question won't be too
> >s> awful. ?I am writing some code that will FTP to a host, and want to
> >s> catch any exception that may occur, take that and print it out
> >s> (eventually put it into a log file and perform some alerting action).
> >s> I've figured out two different ways to do this, and am wondering which
> >s> is the best (i.e. cleanest, 'right' way to proceed). ?I'm also trying
> >s> to understand exactly what occurs for each one.
> >s> The first example:
> >s> from ftplib import FTP
> >s> try:
> >s> ? ? ftp = FTP(ftp_host)
> >s> ? ? ftp.login(ftp_user, ftp_pass)
> >s> except Exception, err:
> >s> ? ? print err
>
> I think you should restrict yourself to those exceptions that are
> related to ftp. Do you want to catch an exception like a misspelling in
> one of the variables?

He quite reasonably could want that, such as if the program is
designed to be run from a cron job, or in some other non-interactive
way.

Just because something is usually a bad idea doesn't mean it always
is.


Carl Banks


From albert at spenarnc.xs4all.nl  Mon Jul 13 22:28:06 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 14 Jul 2009 02:28:06 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
Message-ID: <kmr2uu.d1t@spenarnc.xs4all.nl>

In article <7x8wj4uxnb.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>
>Anyway, Python's overloading of bool(...) is yet another misfeature
>and although it's convenient, the "explicit is better than implicit"
>principle indicates to avoid that sort of trick.

Well, trading "tricks" (I would call it idiom) for explicitness,
made some people (you know ..) hate Pascal.
Einstein introduced the summation convention for indices that
are used twice. Leaving out summation signs is absolutely hideous,
but it has saved generations of physicists of loosing track (and
their minds.)

Also ...

For me there is nothing more clear than a regular expression
search that returns None if nothing matches.

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From albert at spenarnc.xs4all.nl  Mon Jul 13 22:46:19 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 14 Jul 2009 02:46:19 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
	<0260bf8d$0$20657$c3e8da3@news.astraweb.com>
	<7x8wj2agma.fsf@ruckus.brouhaha.com>
Message-ID: <kmr3p7.d9a@spenarnc.xs4all.nl>

In article <7x8wj2agma.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> > but I don't accept that "somethingness"
>> > vs. "nothingness" is the same distinction as truth vs falsehood.
>>
>> It's the distinction used by Python since the dawn of time. Python only
>> grew a bool type a few versions back.
>
>That's true, part of the situation we have now is an artifact of that
>history.
>
>> I'm not talking about the constants True and False (nouns), but about
>> true and false values (adjectives).
>
>But, it seems to me, the constants True and False are the only values
>to which the adjectives "true" and "false" should be applicable to.
>
>>
>> > The idea that the "if"
>> > statement selects between "somethingness" and "nothingness" rather than
>> > between True and False is a bogus re-imagining of the traditional
>> > function of an "if" statement
>>
>> There's nothing bogus about it.
>>
>> > and has been an endless source of bugs in Python code.
>> I wonder why these "endless" bugs weren't important enough to be
>> mentioned in the rationale to PEP 285:
>
>Because adding the bool type doesn't really fix those bugs.
>
>> describing `if x` as the "correct form" and calling scrapping such a
>> feature as "crippling the language".
>
>Certainly, changing "if" would have broken an immense amount of code
>and been a completely unworkable approach.  We are using a fairly
>mature language by now; it has a culture and history that carries
>certain baggage, as one should expect.
>
>> > Look how much confusion it causes here in the newsgroup all the time.
>> The only confusion is that you're causing me. Would you care to link to
>> some?
>
>This current discussion (about bools) came from such confusion just a
>few posts up in this very thread:
>
>    From: upwestdon <upwestdon at gmail.com>
>    Date: Fri, 3 Jul 2009 23:03:39 -0700 (PDT)
>    How about just:
>
>    if not (self.higher and self.lower):
>        return self.higher or self.lower
>
>That test was designed to treat None as a boolean False, without
>noticing that numeric 0 is also treated as False and could make the
>test do the wrong thing.  This is an extremely common type of error.
>
>> > could see some value to having a generic "is_empty" predicate
>> We have that already. It's spelled __bool__ or __nonzero__
>
>That's fine, but under the "explicit is better than implicit"
>principle, it's preferable to call that predicate explicitly:
>"if bool(x): ..." rather than "if x:".  Also, after many years of

Maybe I'm missing something here, but if self.higher contains 0,
wouldn't bool(self.higher) evaluate to False?
So how does this help?

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:25:52 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:25:52 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
Message-ID: <pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>

On Mon, 13 Jul 2009 17:49:23 -0700, Carl Banks wrote:

> On Jul 13, 12:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
>> >>>>> seldan24 <selda... at gmail.com> (s) wrote:
>> >s> Hello,
>> >s> I'm fairly new at Python so hopefully this question won't be too s>
>> >awful. ?I am writing some code that will FTP to a host, and want to s>
>> >catch any exception that may occur, take that and print it out s>
>> >(eventually put it into a log file and perform some alerting action).
>> >s> I've figured out two different ways to do this, and am wondering
>> >which s> is the best (i.e. cleanest, 'right' way to proceed). ?I'm
>> >also trying s> to understand exactly what occurs for each one. s> The
>> >first example:
>> >s> from ftplib import FTP
>> >s> try:
>> >s> ? ? ftp = FTP(ftp_host)
>> >s> ? ? ftp.login(ftp_user, ftp_pass) s> except Exception, err:
>> >s> ? ? print err
>>
>> I think you should restrict yourself to those exceptions that are
>> related to ftp. Do you want to catch an exception like a misspelling in
>> one of the variables?
> 
> He quite reasonably could want that, such as if the program is designed
> to be run from a cron job, or in some other non-interactive way.


Why is it okay for non-interactive programs to silently have incorrect 
behaviour?

What's the point of a cron job that doesn't do what it is supposed to, 
because it has a bug which is silently swallowed?



"I find it amusing when novice programmers believe their main job is 
preventing programs from crashing. ... More experienced programmers 
realize that correct code is great, code that crashes could use 
improvement, but incorrect code that doesn't crash is a horrible 
nightmare."

http://www.pphsg.org/cdsmith/types.html




-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:27:30 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:27:30 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<87eiskktwd.fsf@benfinney.id.au>
Message-ID: <pan.2009.07.14.03.27.30@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 10:09:06 +1000, Ben Finney wrote:

> Instead of catching *all* exceptions at a specific point in your code,
> and then having nothing to do but end the program (possibly after some
> pre-exit action like logging), I think you would be better served by
> installing a custom top-level exception handler.
...
> Any other exceptions that you don't specifically catch will then go
> through to your default handle-it-just-before-we-exit ?sys.excepthook?
> exception handler.



Isn't that risky though? Won't that potentially change the exception-
handling behaviour of functions and classes he imports from other modules?




-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:45:02 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:45:02 GMT
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<h32i2o$eop$1@reader1.panix.com> <h37gv5$r81$1@panix3.panix.com>
	<h3bagu$52m$4@lust.ihug.co.nz> <h3bogf$oo0$1@panix3.panix.com>
	<h3f5dt$dld$3@lust.ihug.co.nz>
Message-ID: <pan.2009.07.14.03.45.03@REMOVE.THIS.cybersource.com.au>

On Mon, 13 Jul 2009 23:22:36 +1200, Lawrence D'Oliveiro wrote:

[stupidity omitted]
> Nope, still doesn't work...


Are we supposed to interpret that post as Dumb Insolence or just Dumb?



-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:49:30 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:49:30 GMT
Subject: Memory error due to big input file
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
	<mailman.3067.1247518893.8015.python-list@python.org>
	<4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
Message-ID: <pan.2009.07.14.03.49.31@REMOVE.THIS.cybersource.com.au>

On Mon, 13 Jul 2009 14:20:13 -0700, Aaron Scott wrote:

>> BTW, you should derive all your classes from something. ?If nothing
>> else, use object.
>> ? class textfile(object):
> 
> Just out of curiousity... why is that? I've been coding in Python for a
> long time, and I never derive my base classes. What's the advantage to
> deriving them?

"Old style" classes (those whose base classes aren't derived from 
anything) have a few disadvantages:


(1) Properties don't work correctly:

>>> class Parrot:  # old-style class
...     def __init__(self):
...             self._x = 3
...     def _setter(self, value):
...             self._x = value
...     def _getter(self):
...             print "Processing ..."
...             return self._x + 1
...     x = property(_getter, _setter)
...
>>> p = Parrot()
>>> p.x
Processing ...
4
>>> p.x = 2
>>> p.x
2

In general, anything that uses the descriptor protocol, not just 
property, will fail to work correctly with old-style classes.


(2) Classes using multiple inheritance with diamond-shaped inheritance 
will be broken.

(3) __slots__ is just an attribute.

(4) super() doesn't work.

And, depending on whether you consider this a disadvantage or an 
advantage:

(5) Special methods like __len__ can be over-ridden on the instance, not 
just the class:

>>> class K:
...     def __len__(self):
...             return 0
...
>>> k = K()
>>> len(k)
0
>>> k.__len__ = lambda : 42
>>> len(k)
42



In their favour:

(1) Less typing.

(2) If you're not using descriptors, including property(), or multiple 
inheritance with diamond diagrams, they work fine.

(3) They're (apparently) a tiny bit faster.



-- 
Steven


From Lily.Gao at autodesk.com  Tue Jul 14 00:30:03 2009
From: Lily.Gao at autodesk.com (Lily Gao)
Date: Mon, 13 Jul 2009 21:30:03 -0700
Subject: How to unbuffer Python's output
Message-ID: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>

Hi, All
I am calling a python program in perl and use redirection,
Like :
`python x.py > 1.log 2>&1`
When x.py crash, I get nothing from 1.log, and if I don?t use redirection, I can get useful log from the screen.
How can I do to make x.py ?s  output un-buffered when redirection log to files ,just exactly same with print to the screen?

When I use perl?s $|=1 to unbuffer output, it take no effect. So I think it may be caused by python.
Thanks!

Thanks,
Lily Gao(??)
ACRD PSEB Catapult TD
+86-21-38664379

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/45488094/attachment.html>

From gagsl-py2 at yahoo.com.ar  Tue Jul 14 01:06:04 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 14 Jul 2009 02:06:04 -0300
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>
Message-ID: <op.uw1kgeg9x6zn5v@gabriel.sleipnir-bsas>

En Mon, 13 Jul 2009 10:11:09 -0300, denis <denis-bz-gg at t-online.de>  
escribi?:

> Matt, how many words are you looking for, in how long a string ?
> Were you able to time any( substr in long_string ) against re.compile
> ( "|".join( list_items )) ?

There is a known algorithm to solve specifically this problem  
(Aho-Corasick), a good implementation should perform better than R.E. (and  
better than the gen.expr. with the advantage of returning WHICH string  
matched)
There is a C extension somewhere implementing Aho-Corasick.

-- 
Gabriel Genellina



From clp2 at rebertia.com  Tue Jul 14 01:32:55 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 22:32:55 -0700
Subject: explode()
In-Reply-To: <eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
Message-ID: <50697b2c0907132232g40dce2c3o776a2f07ef28acf0@mail.gmail.com>

On Mon, Jul 13, 2009 at 11:28 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
> On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
> wrote:
>
>>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>>
>>some_string.split("separator")
>>
>>Cheers,
>>Chris
>
> ? ? What would the equivalent of the PHP function implode be?

"separator".join(a_list_of_strings)

I would recommend you read the Python manual's section on string methods:
http://docs.python.org/library/stdtypes.html#string-methods

Cheers,
Chris
-- 
http://blog.rebertia.com


From usernet at ilthio.net  Tue Jul 14 01:41:40 2009
From: usernet at ilthio.net (Tim Harig)
Date: Tue, 14 Jul 2009 05:41:40 GMT
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
Message-ID: <oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com>

On 2009-07-14, Fred Atkinson <fatkinson at mishmash.com> wrote:
> 	The one thing I really dislike about Python over PHP is that
> Python can usually only appear in the cgi directory (unless other
> arragements are made with your hosting provider or if you reconfigure
> Apache on your own server if you have your own).  With PHP, I can put
> them in any folder on my Web site without any problem.  

That is a server configuration and has nothing to do with Python directly.


From sanu1267 at gmail.com  Tue Jul 14 01:41:52 2009
From: sanu1267 at gmail.com (sanju ps)
Date: Tue, 14 Jul 2009 11:11:52 +0530
Subject: python _binary_ code
Message-ID: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>

Hi

 Can anyone give me solution to create a python binary file (bytecode) other
than pyc file .So my source code be secure.. I am working on ubuntu 9.04
with python2.6.. I

Regards
Sanju
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/1d418def/attachment.html>

From clp2 at rebertia.com  Tue Jul 14 02:00:00 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 23:00:00 -0700
Subject: python _binary_ code
In-Reply-To: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
References: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
Message-ID: <50697b2c0907132300xd593feepbaf5a2be078c93f4@mail.gmail.com>

On Mon, Jul 13, 2009 at 10:41 PM, sanju ps<sanu1267 at gmail.com> wrote:
> Hi
>
> ?Can anyone give me solution to create a python binary file (bytecode) other
> than pyc file .So my source code be secure.. I am working on ubuntu 9.04
> with python2.6.. I

PyInstaller (http://www.pyinstaller.org/) will generate a
self-contained executable, but it won't hide the bytecode (which can
be decompiled w/ decompyle).
It's generally accepted to be impossible (or at least more trouble
than it's worth) to protect Python source.

See http://stackoverflow.com/questions/261638/how-do-i-protect-python-code
for excellent and more detailed answers.

Cheers,
Chris
-- 
http://blog.rebertia.com


From fatkinson at mishmash.com  Tue Jul 14 02:28:32 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Mon, 13 Jul 2009 23:28:32 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
Message-ID: <eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>

On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
wrote:

>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>
>some_string.split("separator")
>
>Cheers,
>Chris

     What would the equivalent of the PHP function implode be?  

	Thanks, 




					Fred 


From fatkinson at mishmash.com  Tue Jul 14 02:36:26 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Mon, 13 Jul 2009 23:36:26 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
Message-ID: <6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>

On Mon, 13 Jul 2009 22:32:55 -0700, Chris Rebert <clp2 at rebertia.com>
wrote:

>On Mon, Jul 13, 2009 at 11:28 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>> On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
>> wrote:
>>
>>>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>>>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>>>
>>>some_string.split("separator")
>>>
>>>Cheers,
>>>Chris
>>
>> ? ? What would the equivalent of the PHP function implode be?
>
>"separator".join(a_list_of_strings)
>
>I would recommend you read the Python manual's section on string methods:
>http://docs.python.org/library/stdtypes.html#string-methods
>
>Cheers,
>Chris

Chris, 

	You always seem to be waiting when I post a question.  Do you
ever sleep?  

	I wish the Python site was as well written as the PHP site. On
the PHP site, I can look up a command and they show not only the docs
on that command but a list of all other commands associated with it.  

	Thanks.  Python is a whole new animal to me.  I'm taking a
course in PHP and Python online right now.  I've done PHP scripting
before though I don't claim to be a whiz on it.  But I'd barely heard
of Python before I took this course.  

	The one thing I really dislike about Python over PHP is that
Python can usually only appear in the cgi directory (unless other
arragements are made with your hosting provider or if you reconfigure
Apache on your own server if you have your own).  With PHP, I can put
them in any folder on my Web site without any problem.  

	Regards, 




						Fred 


From lists at cheimes.de  Tue Jul 14 02:50:16 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 14 Jul 2009 08:50:16 +0200
Subject: python _binary_ code
In-Reply-To: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
References: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
Message-ID: <h3h9r9$39t$1@ger.gmane.org>

sanju ps schrieb:
> Hi
> 
>  Can anyone give me solution to create a python binary file (bytecode) other
> than pyc file .So my source code be secure.. I am working on ubuntu 9.04
> with python2.6.. I

It's impossible to secure your code if it runs on an untrusted computer.
This is true for all programming languages but it's even easier to
decompile code of byte interpreted languages like Python, Java or .NET.

Microsoft has tried to protect its programs, the film industry has tried
it with the movies and RIAA, too. All have failed. You won't have more
luck, though. :)

Christian



From wuwei23 at gmail.com  Tue Jul 14 02:54:11 2009
From: wuwei23 at gmail.com (alex23)
Date: Mon, 13 Jul 2009 23:54:11 -0700 (PDT)
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org> 
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org> 
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
Message-ID: <e47c89c6-3e16-48c1-b257-c53642fd9c0b@13g2000prl.googlegroups.com>

Fred Atkinson <fatkin... at mishmash.com> wrote:
> ? ? ? ? I wish the Python site was as well written as the PHP site. On
> the PHP site, I can look up a command and they show not only the docs
> on that command but a list of all other commands associated with it. ?

Hey Fred,

My problem is the complete opposite, I wish I could as easily
interrogate objects in PHP about their behaviour as I can Python :)

In case you're not familiar with this, you can see what methods are
attached to an object using the intepreter via dir() and see the
associated docstring for them via help(). Try looking at 'dir(str)'
for a list of methods that strings recognise, then 'help(str.join)' to
see the help on join.

This is such a handy ability to have that I miss this casual
introspection in everything else in which I'm required to develop.

Hope this helps.


From amrita at iisermohali.ac.in  Tue Jul 14 02:57:29 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Tue, 14 Jul 2009 12:27:29 +0530 (IST)
Subject: copy a file
Message-ID: <14186.210.212.36.65.1247554649.squirrel@www.iisermohali.ac.in>


Dear all,

Can anyone tell me that suppose i want to copy few lines from one text
file to another then how can i do that.Looking forward for soon reply.

Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From ben+python at benfinney.id.au  Tue Jul 14 02:59:07 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 14 Jul 2009 16:59:07 +1000
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<87eiskktwd.fsf@benfinney.id.au>
	<pan.2009.07.14.03.27.30@REMOVE.THIS.cybersource.com.au>
Message-ID: <873a8zlphg.fsf@benfinney.id.au>

Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:

> Isn't that risky though? Won't that potentially change the exception-
> handling behaviour of functions and classes he imports from other
> modules?

No, any existing ?except? clause will be unaffected by re-binding
?sys.excepthook?. As I understand the documentation, that function is
called only if the exception is uncaught by anything else.

    >>> 1 / 0
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    ZeroDivisionError: integer division or modulo by zero

    >>> import sys
    >>> def reverse_handler(exc_type, exc_instance, exc_traceback):
    ...     print exc_type.__name__[::-1], str(exc_instance)[::-1]
    ...
    >>> sys.excepthook = reverse_handler

    >>> try:
    ...     1 / 0
    ... except ZeroDivisionError:
    ...     print "You created a black hole."
    ... 
    You created a black hole.
    >>> 1 / 0
    rorrEnoisiviDoreZ orez yb oludom ro noisivid regetni

In other words, it is the function that (unless re-bound) prints the
traceback we're all familiar with when an exception is uncaught. It is
exposed via the name ?sys.excepthook? precisely for the purpose of
changing the default handler for uncaught exceptions

-- 
 \         ?I have yet to see any problem, however complicated, which, |
  `\      when you looked at it in the right way, did not become still |
_o__)                                more complicated.? ?Paul Anderson |
Ben Finney


From hackingkk at gmail.com  Tue Jul 14 03:07:13 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Tue, 14 Jul 2009 12:37:13 +0530
Subject: copy a file
In-Reply-To: <14186.210.212.36.65.1247554649.squirrel@www.iisermohali.ac.in>
References: <14186.210.212.36.65.1247554649.squirrel@www.iisermohali.ac.in>
Message-ID: <1247555233.3329.18.camel@krishna-laptop>

On Tue, 2009-07-14 at 12:27 +0530, amrita at iisermohali.ac.in wrote:
> Dear all,
> 
> Can anyone tell me that suppose i want to copy few lines from one text
> file to another then how can i do that.Looking forward for soon reply.
> 

very simple.  open one file and open the source file.
seek till to the point where u want to start copying and loop till the
end with readline function.
then write it to the destination file.

To find the starting point, keep looping through the content and come
out of that loop when you find a match to the word you are looking for.
happy hacking.
Krishnakant.



From pavlovevidence at gmail.com  Tue Jul 14 04:30:48 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 01:30:48 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
Message-ID: <93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>

On Jul 13, 8:25?pm, Steven D'Aprano
<ste... at REMOVE.THIS.cybersource.com.au> wrote:
> On Mon, 13 Jul 2009 17:49:23 -0700, Carl Banks wrote:
> > On Jul 13, 12:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >> >>>>> seldan24 <selda... at gmail.com> (s) wrote:
> >> >s> Hello,
> >> >s> I'm fairly new at Python so hopefully this question won't be too s>
> >> >awful. ?I am writing some code that will FTP to a host, and want to s>
> >> >catch any exception that may occur, take that and print it out s>
> >> >(eventually put it into a log file and perform some alerting action).
> >> >s> I've figured out two different ways to do this, and am wondering
> >> >which s> is the best (i.e. cleanest, 'right' way to proceed). ?I'm
> >> >also trying s> to understand exactly what occurs for each one. s> The
> >> >first example:
> >> >s> from ftplib import FTP
> >> >s> try:
> >> >s> ? ? ftp = FTP(ftp_host)
> >> >s> ? ? ftp.login(ftp_user, ftp_pass) s> except Exception, err:
> >> >s> ? ? print err
>
> >> I think you should restrict yourself to those exceptions that are
> >> related to ftp. Do you want to catch an exception like a misspelling in
> >> one of the variables?
>
> > He quite reasonably could want that, such as if the program is designed
> > to be run from a cron job, or in some other non-interactive way.
>
> Why is it okay for non-interactive programs to silently have incorrect
> behaviour?
>
> What's the point of a cron job that doesn't do what it is supposed to,
> because it has a bug which is silently swallowed?

Seriously, do you *ever* take more than 2 seconds to consider whether
you might be missing something obvious before following up with these
indignant knee-jerk responses?

I never said a thing about swallowing errors.  I was talking about
catching exceptions, whence you might do all kinds of things besides
swallowing (like logging).  I was pointing out there are reasons why
you might want to catch variable misspelling errors when you're
running non-interactively (like for instance, to log the error
somewhere).

Or would you rather let all unexpected exceptions print to standard
error, which is often a black hole in non-interactive sitations?


Carl Banks


From nelson1977 at gmail.com  Tue Jul 14 04:34:10 2009
From: nelson1977 at gmail.com (nelson -)
Date: Tue, 14 Jul 2009 10:34:10 +0200
Subject: Remote audio recording in a multiuser environment
Message-ID: <f44750160907140134g6b3c0aeh7fcddf6a3187c070@mail.gmail.com>

Hi all!
   I'm developing an application that will be used in a school. It
will allow client connected over ssh to liste to a multimedia file on
the server. The server componente will record the audio taken from a
specified client microphone, or it would pair two client, allowing
them to communicate each other registering the conversation.

I think to use pygst to record the microphone, but i can' figure out
how to register remote sound and how to create the channel between two
client. Do you think i have to use twisted (i don't know this
framework at all), or there is a simple solution?

I will surely use wxpython for the UI on the client and on the server.

Thank for any advice,
  nelson

-- 
Consulenze Linux e Windows

http://nelsonenterprise.net


From tedwards at it.dcs.ch  Tue Jul 14 05:11:13 2009
From: tedwards at it.dcs.ch (Tim Edwards)
Date: Tue, 14 Jul 2009 11:11:13 +0200
Subject: 'unable to execute cc: No such file or directory' with distutils
	on Solaris
Message-ID: <4A5C4BB1.4050204@it.dcs.ch>

Hi,

I'm trying to compile http://sourceforge.net/projects/astlib/ 0.17.1 on
a Solaris 10 SPARC system. This python module uses distutils.ccompiler.
The problem seems to be that although I have gcc installed in
/usr/sfw/bin/gcc it keeps trying to execute the command 'cc', which
doesn't work:

cc -c actread.c -o actread.o
unable to execute cc: No such file or directory
error: command 'cc' failed with exit status 1


I've tried modifying the setup.py file to specify "cc.compiler =
'/usr/sfw/bin/gcc'" and setting the $CC envrionment var.
But I get the same error everytime. Can someone suggest how to change
where distutils is looking for the compiler?

Thanks

Tim Edwards


From rileycrane at gmail.com  Tue Jul 14 05:12:15 2009
From: rileycrane at gmail.com (R C)
Date: Tue, 14 Jul 2009 02:12:15 -0700 (PDT)
Subject: MySQLdb + SSH Tunnel
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
Message-ID: <d01ebee4-543e-4f13-9e8e-33ccd08ce24e@o13g2000vbl.googlegroups.com>

Got it working.  Thanks for your help

1) login to B
2) setup a tunnel in the shell   machine-B> ssh -L
B_ip_address:B_port:C_ip_address:C_port user at C_ip_address

   for example:
     machine-B has ip 1.1.1.1
     machine-C has ip 2.2.2.2

   then I would type:
   machine-B> ssh -L 1.1.1.1:3307:2.2.2.2:3306 user at 2.2.2.2

   now the code that is running on machine-A would use MySQLdb in the
following way

   import MySQLdb
   connection = MySQLdb.connect
(user='myname',passwd='mypass',db='mydb',host='1.1.1.1',port=3307)

   NOTE: the port is an integer, NOT a string



On Jul 12, 9:18?pm, Riley Crane <vodkal... at gmail.com> wrote:
> OVERVIEW:
> I am running a script on one machine that connects to a MySQL database
> on another machine that is outside of our university's domain.
> According to the administrator, network policies do not allow the
> compute nodes to access machines outside of our university's domain.
>
> COMPUTERS:
> A = compute node within university (I do not have shell access)
> B = 2nd machine within university that does not block outside
> connections (I have root access)
> C = machine outside of university (I have root access)
> mysqldb on A cannot connect to C ....but.....
> mysqldb on A can connect to B
>
> WHAT I WOULD LIKE TO DO:
> Is it possible to set something up where A talks to a port on B, and
> that port is actually nothing more than 3306 on C? ?Can I do this with
> an SSH tunnel?
>
> Can anyone please give precise instructions?



From vodkalove at gmail.com  Tue Jul 14 05:14:19 2009
From: vodkalove at gmail.com (Riley Crane)
Date: Tue, 14 Jul 2009 02:14:19 -0700 (PDT)
Subject: MySQLdb + SSH Tunnel
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
Message-ID: <03687615-f8b2-427f-af2d-4cfcb23604f8@f33g2000vbm.googlegroups.com>

Got it working.  Thanks for your help!

1) login to B
2) setup a tunnel in the shell   machine-B> ssh -L
B_ip_address:B_port:C_ip_address:C_port user at C_ip_address

   for example:
     machine-B has ip 1.1.1.1
     machine-C has ip 2.2.2.2

   then I would type:
   machine-B> ssh -L 1.1.1.1:3307:2.2.2.2:3306 user at 2.2.2.2

   now the code that is running on machine-A would use MySQLdb in the
following way

   import MySQLdb
   connection = MySQLdb.connect
(user='myname',passwd='mypass',db='mydb',host='1.1.1.1',port=3307)

   NOTE: the port is an integer, NOT a string


On Jul 12, 9:18?pm, Riley Crane <vodkal... at gmail.com> wrote:
> OVERVIEW:
> I am running a script on one machine that connects to a MySQL database
> on another machine that is outside of our university's domain.
> According to the administrator, network policies do not allow the
> compute nodes to access machines outside of our university's domain.
>
> COMPUTERS:
> A = compute node within university (I do not have shell access)
> B = 2nd machine within university that does not block outside
> connections (I have root access)
> C = machine outside of university (I have root access)
> mysqldb on A cannot connect to C ....but.....
> mysqldb on A can connect to B
>
> WHAT I WOULD LIKE TO DO:
> Is it possible to set something up where A talks to a port on B, and
> that port is actually nothing more than 3306 on C? ?Can I do this with
> an SSH tunnel?
>
> Can anyone please give precise instructions?



From steven at REMOVE.THIS.cybersource.com.au  Tue Jul 14 05:14:52 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 09:14:52 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
Message-ID: <pan.2009.07.14.09.14.52@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 01:30:48 -0700, Carl Banks wrote:

> Seriously, do you *ever* take more than 2 seconds to consider whether
> you might be missing something obvious before following up with these
> indignant knee-jerk responses?

Obviously not.


[...]
> Or would you rather let all unexpected exceptions print to standard
> error, which is often a black hole in non-interactive sitations?

Fair point. Of course you're right.



-- 
Steven


From hartley79 at gmail.com  Tue Jul 14 05:22:24 2009
From: hartley79 at gmail.com (hartley)
Date: Tue, 14 Jul 2009 02:22:24 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com>
Message-ID: <51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com>

> > I'm very new at wrapping Python/C, and I have run into some problems.
>
> > I have one python module that provides me with a list (provideBuffer
> > in provideBuff.py):
>
> > ?Py_Initialize();
> > ? ? ? ? pName = PyString_FromString("provideBuff");
> > ? ? ? ? pModule = PyImport_Import(pName);
>
> > ? ? ? ? pFunc = PyObject_GetAttrString(pModule,"provideBuffer");
>
> > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > pValue is now a PyList - i've even verified this with:
>
> > int a = PyList_Check(pValue);
> > ? ? ? ? printf("%d\n", a);
>
> > However, I want to send this PyList to another python module,
>
> Please explain "send" ... do you mean the C equivalent of the Python
> statement C_embedding.buff = the_pylist ?
>
> BTW C-embedding would trigger a syntax error in Python source; best to
> avoid ...


I'm sorry I'm not using the proper terms when trying to describe this
- i've never really learnt those terms, I guess i should do that one
day.


Imagine that the python function C-embedding.buff looks like this:

def buff(a):
    if isinstance(a,list):
        print "success"

I want to send, pass, call, whatever a list argument from the C code
onto this function. As simple as this - how can you call a function in
python from C, and providing a python list as an argument?

As I wrote earlier - I already have a PyList, called pValue. But I
have not been able to use this as an argument for C-embedding.buff
using the code I described last time.


> > but I
> > don't know how to do this. Initially I though I could just do like
> > above, only swapping NULL with pValue, but that is not working.
>
> > pName2 = PyString_FromString("C-embedding");
> > pModule2 = PyImport_Import(pName2);
> > pFunc2 = PyObject_GetAttrString(pModule2,"buff");
>
> Get?? Do you want Set? Is buff a Python function? Or is it the
> destination of the "sending"? Any good reason for not checking the
> return value for an error? [Rhetorical question; answer == "No"]
>
> > pValue2 = PyObject_CallObject(pFunc2,pValue);
>
> CallObject?? You used this before because you had a function and
> wanted to call it because it returned you a value .... now you want to
> do one of (in Python terms)
>
> value = amodule.anattr
> value = getattr(amodule, "anattr")
>
> or
>
> amodule.anattr = value
> setattr(amodule, "anattr", value)
>
> > pValue2 is now False!
>
> False?? Do you mean the C NULL?
>
> > So i guess i cannot pass pValue as an argument
> > to PyObject_CallObject when i want to pass an python list as an
> > argument. But how must a go about to make this work?
>
> It's mainly just a matter of (1) knowing what you want to do (2)
> picking the API that does what you want (3) checking the returned
> value for error after every call.
>
> HTH,
> John



From clp2 at rebertia.com  Tue Jul 14 05:25:15 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 02:25:15 -0700
Subject: How to unbuffer Python's output
In-Reply-To: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
References: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
Message-ID: <50697b2c0907140225s59df742fpdfb2673d837e4f3d@mail.gmail.com>

2009/7/13 Lily Gao <Lily.Gao at autodesk.com>:
> Hi, All
>
> I am calling a python program in perl and use redirection,
>
> Like :
>
> `python x.py > 1.log 2>&1`
>
> When x.py crash, I get nothing from 1.log, and if I don?t use redirection, I
> can get useful log from the screen.
>
> How can I do to make x.py ?s? output un-buffered when redirection log to
> files ,just exactly same with print to the screen?

Use the -u flag to python:
?u    Force stdin, stdout and stderr to be totally unbuffered.

python -u x.py > 1.log 2>&1

Cheers,
Chris
-- 
http://blog.rebertia.com


From amrita at iisermohali.ac.in  Tue Jul 14 05:43:17 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Tue, 14 Jul 2009 15:13:17 +0530 (IST)
Subject: copy a few lines
Message-ID: <23461.210.212.36.65.1247564597.squirrel@www.iisermohali.ac.in>



Dear all,

I want to know if i want to copy one paragraph from one text file to
another then what command i have to use in python.Looking forwaard for
soon reply.


Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From clp2 at rebertia.com  Tue Jul 14 05:50:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 02:50:13 -0700
Subject: copy a few lines
In-Reply-To: <23461.210.212.36.65.1247564597.squirrel@www.iisermohali.ac.in>
References: <23461.210.212.36.65.1247564597.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907140250lb2bdc63y4872c522cf216953@mail.gmail.com>

On Tue, Jul 14, 2009 at 2:43 AM, <amrita at iisermohali.ac.in> wrote:
>
>
> Dear all,
>
> I want to know if i want to copy one paragraph from one text file to
> another then what command i have to use in python.Looking forwaard for
> soon reply.

Please don't double-post. It wastes everyone's time, especially when
(a) your previous post was less than 3 hours ago, and
(b) your previous post got a response.

If you're refining your question, it's best to just reply to your own
prior post.

Also, you're going to need to define what precisely qualifies as a
"paragraph" for your purposes.

- Chris
-- 
http://blog.rebertia.com


From jon at peirce.org.uk  Tue Jul 14 06:28:19 2009
From: jon at peirce.org.uk (JonPeirce)
Date: Tue, 14 Jul 2009 03:28:19 -0700 (PDT)
Subject: renice
In-Reply-To: <1193438701.979110.114360@v3g2000hsg.googlegroups.com>
References: <13422771.post@talk.nabble.com>
	<1193417206.734440.268840@o38g2000hse.googlegroups.com>
	<1193438701.979110.114360@v3g2000hsg.googlegroups.com>
Message-ID: <24477000.post@talk.nabble.com>



Note that with os.nice you can only *decrease* priority. For increasing
priority you need to run;
os.system("sudo renice -n %s %s" % (new_nice, os.getpid()))
or simply set the nice level when you run python in the first place (you do
also need sudo for this):
sudo nice -n -15 python myScript.py

Jon
-- 
View this message in context: http://www.nabble.com/renice-tp13422771p24477000.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From hartley79 at gmail.com  Tue Jul 14 06:32:08 2009
From: hartley79 at gmail.com (hartley)
Date: Tue, 14 Jul 2009 03:32:08 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com>
Message-ID: <3d3d9f7e-5c57-414b-9363-f1ebfca0f9e2@r25g2000vbn.googlegroups.com>

On Jul 13, 6:35?pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 14, 1:47?am, hartley <hartle... at gmail.com> wrote:
>
>
>
> > I'm very new at wrapping Python/C, and I have run into some problems.
>
> > I have one python module that provides me with a list (provideBuffer
> > in provideBuff.py):
>
> > ?Py_Initialize();
> > ? ? ? ? pName = PyString_FromString("provideBuff");
> > ? ? ? ? pModule = PyImport_Import(pName);
>
> > ? ? ? ? pFunc = PyObject_GetAttrString(pModule,"provideBuffer");
>
> > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > pValue is now a PyList - i've even verified this with:
>
> > int a = PyList_Check(pValue);
> > ? ? ? ? printf("%d\n", a);
>
> > However, I want to send this PyList to another python module,
>
> Please explain "send" ... do you mean the C equivalent of the Python
> statement C_embedding.buff = the_pylist ?
>
> BTW C-embedding would trigger a syntax error in Python source; best to
> avoid ...
>
> > but I
> > don't know how to do this. Initially I though I could just do like
> > above, only swapping NULL with pValue, but that is not working.
>
> > pName2 = PyString_FromString("C-embedding");
> > pModule2 = PyImport_Import(pName2);
> > pFunc2 = PyObject_GetAttrString(pModule2,"buff");
>
> Get?? Do you want Set? Is buff a Python function? Or is it the
> destination of the "sending"? Any good reason for not checking the
> return value for an error? [Rhetorical question; answer == "No"]
>
> > pValue2 = PyObject_CallObject(pFunc2,pValue);
>
> CallObject?? You used this before because you had a function and
> wanted to call it because it returned you a value .... now you want to
> do one of (in Python terms)
>
> value = amodule.anattr
> value = getattr(amodule, "anattr")
>
> or
>
> amodule.anattr = value
> setattr(amodule, "anattr", value)
>
> > pValue2 is now False!
>
> False?? Do you mean the C NULL?
>
> > So i guess i cannot pass pValue as an argument
> > to PyObject_CallObject when i want to pass an python list as an
> > argument. But how must a go about to make this work?
>
> It's mainly just a matter of (1) knowing what you want to do (2)
> picking the API that does what you want (3) checking the returned
> value for error after every call.
>
> HTH,
> John

I tried to keep this simple, but I realise that since I'm not using
the terminology correctly, it may be hard understand what I mean.

I'll do something even simpler:

Say you have the function:

C-embedding.buff

def buff(s):
	if isinstance(s,list):
           return s

how can i call (use,invoke,?? - sorry, about the terminology again)
this function from C so that I call this function with an argument
that is (accepted as) a python list?

foo.bar

def bar():


pName = PyString_FromString("foo");
pModule = PyImport_Import(pName);
pFunc = PyObject_GetAttrString(pModule,"bar");
pValue = PyObject_CallObject(pFunc,NULL);


From dana_at_work at yahoo.com  Tue Jul 14 07:32:35 2009
From: dana_at_work at yahoo.com (dana)
Date: Tue, 14 Jul 2009 04:32:35 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
	<mailman.2960.1247242538.8015.python-list@python.org>
Message-ID: <9e63df1c-9757-4e94-98a0-f49b383a3ad6@h30g2000vbr.googlegroups.com>

On Jul 10, 12:15?pm, "M.-A. Lemburg" <m... at egenix.com> wrote:
> If you're looking for a stable and maintained ODBC for Python,
> have a look at our mxODBC extension or mxODBC Connect package:
> http://www.egenix.com/products/python/mxODBC/http://www.egenix.com/products/python/mxODBCConnect/

I'm looking for a free module. Is yours a commercial product?

Thanks.

Dana


From torf at torfbold.com  Tue Jul 14 07:38:45 2009
From: torf at torfbold.com (Florian Brucker)
Date: Tue, 14 Jul 2009 13:38:45 +0200
Subject: Efficient binary search tree stored in a flat array?
In-Reply-To: <5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
Message-ID: <4a5c5e7f$0$30235$9b4e6d93@newsspool1.arcor-online.net>

Douglas Alan wrote:
> Thank you. My question wasn't intended to be Python specific, though.
> I am just curious for purely academic reasons about whether there is
> such an algorithm. All the sources I've skimmed only seem to the
> answer the question via omission. Which is kind of strange, since it
> seems to me like an obvious question to ask.

IIRC comp.programming would be the place to ask such questions.


HTH,
Florian


From __peter__ at web.de  Tue Jul 14 07:45:47 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 14 Jul 2009 13:45:47 +0200
Subject: Tkinter / Entry widget problem
References: <mailman.3066.1247516702.8015.python-list@python.org>
Message-ID: <h3hr54$p6s$02$1@news.t-online.com>

Andras Szabo wrote:

> Hello. I searched the archives but couldn't find a solution to a
> problem related to the Entry widget in Tkinter.
> 
> When creating a pop-up window in an app, which contains an Entry
> widget, I want this widget to contain some default string, to have all
> this default string selected (as if the user had manually selected
> everything), and to have the focus transferred to this widget.
> 
> (The idea is then that if the window pops up, the user won't have to
> click or press Tab any more before being able to type what is needed
> in the textbox, overwriting what is written there already.)
> 
> I thought this might be the way to go:
> 
> entrybox=Entry(toplevel_parent_window)
> entrybox.insert(0,"Some default string")
> entrybox.select_range(0,END)
> entrybox.focus_set()
> entrybox.pack()
> 
> But it doesn't seem to work - the focus is not transferred to the
> Entry widget, and the text does not appear to be selected (even though
> after this entrybox.selection_present() returns True).
> 
> What am I doing wrong?

Nothing, I would think. Can you post a minimal runnable example?

Peter



From ldo at geek-central.gen.new_zealand  Tue Jul 14 07:48:57 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 14 Jul 2009 23:48:57 +1200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
Message-ID: <h3hrb9$9c$2@lust.ihug.co.nz>

In message <93f6a517-63d8-4c80-
bf19-4614b70999db at m7g2000prd.googlegroups.com>, Carl Banks wrote:

> Or would you rather let all unexpected exceptions print to standard
> error, which is often a black hole in non-interactive sitations?

Since when?

Cron, for example, collects standard error and mails it to you.



From ldo at geek-central.gen.new_zealand  Tue Jul 14 07:50:34 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 14 Jul 2009 23:50:34 +1200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<mailman.3053.1247495610.8015.python-list@python.org>
	<d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>
Message-ID: <h3hreb$9c$3@lust.ihug.co.nz>

In message <d82cea0b-3327-4a27-
b300-08975f7c0606 at p28g2000vbn.googlegroups.com>, seldan24 wrote:

> For this particular script, all exceptions are fatal
> and I would want them to be.  I just wanted a way to catch them and
> log them prior to program termination.

You don't need to. They will be written to standard error anyway.



From ldo at geek-central.gen.new_zealand  Tue Jul 14 07:52:40 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 14 Jul 2009 23:52:40 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
	<h3bogf$oo0$1@panix3.panix.com> <h3f5dt$dld$3@lust.ihug.co.nz>
	<pan.2009.07.14.03.45.03@REMOVE.THIS.cybersource.com.au>
Message-ID: <h3hri9$9c$4@lust.ihug.co.nz>

In message <pan.2009.07.14.03.45.03 at REMOVE.THIS.cybersource.com.au>, Steven 
D'Aprano wrote:

> Are we supposed to interpret that post as Dumb Insolence or just Dumb?

"Insolence" indeed ... another wanker to plonk, I think.



From piet at cs.uu.nl  Tue Jul 14 08:10:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 14:10:20 +0200
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
Message-ID: <m2r5wjzcr7.fsf@cs.uu.nl>

>>>>> Douglas Alan <darkwater42 at gmail.com> (DA) wrote:

>DA> On Jul 13, 3:57?pm, a... at pythoncraft.com (Aahz) wrote:
>>> Still, unless your list is large (more than thousands of elements),
>>> that's the way you should go. ?See the bisect module. ?Thing is, the
>>> speed difference between C and Python means the constant for insertion
>>> and deletion is very very small relative to bytecode speed. ?Keep in
>>> mind that Python's object/binding model means that you're shuffling
>>> pointers in the list rather than items.

>DA> Thank you. My question wasn't intended to be Python specific, though.
>DA> I am just curious for purely academic reasons about whether there is
>DA> such an algorithm. All the sources I've skimmed only seem to the
>DA> answer the question via omission. Which is kind of strange, since it
>DA> seems to me like an obvious question to ask.

Of course you can take any BST algorithm and replace pointers by indices
in the array and allocate new elements in the array. But then you need
array elements to contain the indices for the children explicitely.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From sjmachin at lexicon.net  Tue Jul 14 08:21:30 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 05:21:30 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com>
Message-ID: <cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com>

On Jul 14, 7:22?pm, hartley <hartle... at gmail.com> wrote:
> > > I'm very new at wrapping Python/C, and I have run into some problems.
[snip]

> > > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > > pValue is now a PyList - i've even verified this with:
>
> > > int a = PyList_Check(pValue);
> > > ? ? ? ? printf("%d\n", a);
>
> > > However, I want to send this PyList to another python module,
>
> > Please explain "send" ... do you mean the C equivalent of the Python
> > statement C_embedding.buff = the_pylist ?
>
> > BTW C-embedding would trigger a syntax error in Python source; best to
> > avoid ...
>
> I'm sorry I'm not using the proper terms when trying to describe this
> - i've never really learnt those terms, I guess i should do that one
> day.

Today would be a good day to start :-)

>
> Imagine that the python function C-embedding.buff looks like this:
>
> def buff(a):
> ? ? if isinstance(a,list):
> ? ? ? ? print "success"
>
> I want to send, pass, call, whatever a list argument from the C code
> onto this function. As simple as this - how can you call a function in
> python from C, and providing a python list as an argument?
>
> As I wrote earlier - I already have a PyList, called pValue. But I
> have not been able to use this as an argument for C-embedding.buff
> using the code I described last time.
>
> > > but I
> > > don't know how to do this. Initially I though I could just do like
> > > above, only swapping NULL with pValue, but that is not working.
>
> > > pName2 = PyString_FromString("C-embedding");
> > > pModule2 = PyImport_Import(pName2);
> > > pFunc2 = PyObject_GetAttrString(pModule2,"buff");

> >  Any good reason for not checking the
> > return value for an error? [Rhetorical question; answer == "No"]
>
> > > pValue2 = PyObject_CallObject(pFunc2,pValue);

Your problem is here, in the second arg of PyObject_CallObject. It
should be either NULL if no args are being supplied, or a tuple
containing the args if 1 or more args are being supplied. pValue is
the arg itself; you need to wrap it in a tuple.

See http://docs.python.org/c-api/object.html#PyObject_CallObject

Actually you might like to use this instead (no tuple hassles):

http://docs.python.org/c-api/object.html#PyObject_CallFunctionObjArgs

What are you using as a source of information? Have you read this:

http://docs.python.org/extending/embedding.html#pure-embedding ?

It contains a very thorough example of calling a Python function from
C, with all the reference-counting and error-checking stuff and it's
quite runnable -- I've just now compiled it and run it (1) as-is (2)
changed to pass a list instead of multiple ints (3) changed again to
emulate you trying to pass the list directly instead of wrapped in a
tuple ... here's the result:

TypeError: argument list must be a tuple
Call failed

Oh by the way, you can get away with C-embedding as a module name if
you are importing it from C, but importing it from Python [so that you
could test it independently of your C program] presents a difficulty
(syntax error) ... better to change it to c_embedding.

> > It's mainly just a matter of (1) knowing what you want to do (2)
> > picking the API that does what you want (3) checking the returned
> > value for error after every call.

HTH,
John


From candide at free.invalid  Tue Jul 14 08:37:24 2009
From: candide at free.invalid (candide)
Date: Tue, 14 Jul 2009 14:37:24 +0200
Subject: Python code for testing well parenthesized expression
Message-ID: <4a5c7c04$0$16808$426a34cc@news.free.fr>

Hi,

I'm trying to implement in Python a function testing if an expression is well
parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik" is correctly
parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.

My code follows at the end.

If you have a better algorithm or a better Python code (I'm a beginner in the
Python world), don't hesitate ...



#----------------------------------

# The obvious iterative version
def i(s):
    op = 0 # op : open parenthesis
    for k in range(len(s)):
        op += (s[k] == '(') - (s[k] == ')')
        if op < 0: break
    return op


# Recursive implementation of the preceding version
def r(s,op=0): # op : open parenthesis
    if len(s)==0:
        return op
    elif s[0]=='(':
        return r(s[1:],op+1)
    elif s[0]==')':
        if op==0:
            return -1
        else :
            return r(s[1:],op-1)
    else :
        return r(s[1:],op)


# "functional" style version
def f(s):
    if (len(s)!=0 and s[0]=='('):
        z=f(s[1:])
        if len(z)!=0:
            return f(z[1:])
        else:
            return None
    elif len(s)==0 or s[0] == ')':
        return s
    else:
        return f(s[1:])


def test(t,f):
    for z in t:
        print (z,f(z)==0)

# True True True True True False False
t=["zx4er(1(er(Yy)ol)ol)ik",
"x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)",
"a(ty(y(y(bn)))lokl)kl",
"xc(er(tgy(rf(yh)()uj)ki))",
"e",
"rf(tgt)juj)jkik(jun)",
"zx(4er(1(er(Yy)ol)ol)ik"]

test(t,i)
print

test(t,r)
print

def test(t):
    for s in t: print (s,f(s)=="")

test(t)
#-------------------------------------------

and the corresponding output :


('zx4er(1(er(Yy)ol)ol)ik', True)
('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)', True)
('a(ty(y(y(bn)))lokl)kl', True)
('xc(er(tgy(rf(yh)()uj)ki))', True)
('e', True)
('rf(tgt)juj)jkik(jun)', False)
('zx(4er(1(er(Yy)ol)ol)ik', False)

('zx4er(1(er(Yy)ol)ol)ik', True)
('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)', True)
('a(ty(y(y(bn)))lokl)kl', True)
('xc(er(tgy(rf(yh)()uj)ki))', True)
('e', True)
('rf(tgt)juj)jkik(jun)', False)
('zx(4er(1(er(Yy)ol)ol)ik', False)

('zx4er(1(er(Yy)ol)ol)ik', True)
('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)', True)
('a(ty(y(y(bn)))lokl)kl', True)
('xc(er(tgy(rf(yh)()uj)ki))', True)
('e', True)
('rf(tgt)juj)jkik(jun)', False)
('zx(4er(1(er(Yy)ol)ol)ik', False)


From jeremy+complangpython at jeremysanders.net  Tue Jul 14 08:57:21 2009
From: jeremy+complangpython at jeremysanders.net (Jeremy Sanders)
Date: Tue, 14 Jul 2009 13:57:21 +0100
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <h3hvbh$sjl$1@gemini.csx.cam.ac.uk>

candide wrote:

> I'm trying to implement in Python a function testing if an expression is
> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
> 
> My code follows at the end.
> 
> If you have a better algorithm or a better Python code (I'm a beginner in
> the Python world), don't hesitate ...

Don't you want to just test that the number of "("s equals the number of 
")"s or am I missing the point?

>>> a='aAAA(bbb(cc)))'
>>> a.count('(') == a.count(')')

Jeremy

-- 
Jeremy Sanders
http://www.jeremysanders.net/



From adrian.dziubek at gmail.com  Tue Jul 14 08:59:51 2009
From: adrian.dziubek at gmail.com (Adrian Dziubek)
Date: Tue, 14 Jul 2009 05:59:51 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <c3635e15-37b1-431d-aeef-7b90f29a9c3d@f10g2000vbf.googlegroups.com>

Strings are immutable, so your method of slicing one letter at time
will be building lots of them. That shouldn't hurt you here, but it
will when you hit a bigger problem. In the i() there should be "return
op == 0" on the end.

def well(expr):
  mapping = {'(':1, ')':-1}
  count = 0
  for s in expr:
    if s in mapping:
      count += mapping[s]
    if s < 0:
      return False
  return count == 0

def test_well():
  examples = [
    ('zx4er(1(er(Yy)ol)ol)ik', True),
    ('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)',
True),
    ('a(ty(y(y(bn)))lokl)kl', True),
    ('xc(er(tgy(rf(yh)()uj)ki))', True),
    ('e', True),
    ('rf(tgt)juj)jkik(jun)', False),
    ('zx(4er(1(er(Yy)ol)ol)ik', False),
  ]
  for expr, expected in examples:
    assert well(expr) == expected


From adrian.dziubek at gmail.com  Tue Jul 14 09:04:06 2009
From: adrian.dziubek at gmail.com (Adrian Dziubek)
Date: Tue, 14 Jul 2009 06:04:06 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
Message-ID: <89cdf891-04e2-4c21-9043-cfdf91dd136a@j9g2000vbp.googlegroups.com>

> Don't you want to just test that the number of "("s equals the number of
> ")"s or am I missing the point?
I had this idea too, but there is additional requirement that any
beginning must have greater or equal number of '(' than ')'.
--
Adrian


From martin.hellwig at dcuktec.org  Tue Jul 14 09:05:38 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 14 Jul 2009 14:05:38 +0100
Subject: Python code for testing well parenthesized expression
In-Reply-To: <4a5c7c04$0$16808$426a34cc@news.free.fr>
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <YvGdnSP5s64-H8HXnZ2dnUVZ8u2dnZ2d@bt.com>

candide wrote:
To add to your implementations; a readable version:

+++file parantheses.py+++
"""Parentheses Module Test"""

def parentheses_are_paired(input_string):
     "Check if 'input_string' contains paired parentheses, if so return 
True."
     parenthesis_count = 0
     parenthesis_open = '('
     parenthesis_close = ')'

     for character in input_string:
         if character == parenthesis_open:
             parenthesis_count += 1
         elif character == parenthesis_close:
             parenthesis_count -= 1


     if parenthesis_count == 0:
         return(True)
     else:
         if parenthesis_count < 0:
             error_text = 'More closing parantheses than opening ones'

         elif parenthesis_count > 0:
             error_text = 'More opening parantheses than closing ones'

         raise(ValueError(error_text))

if __name__ == '__main__':
     TEST_TRUE = 'zx4er(1(er(Yy)ol)ol)ik'
     TEST_ERROR = 'zx(4er(1(er(Yy)ol)ol)ik'

     print(parentheses_are_paired(TEST_TRUE))

     try:
         print(parentheses_are_paired(TEST_ERROR))
     except(ValueError):
         print(False)

---file parantheses.py---

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From jeremy+complangpython at jeremysanders.net  Tue Jul 14 09:06:42 2009
From: jeremy+complangpython at jeremysanders.net (Jeremy Sanders)
Date: Tue, 14 Jul 2009 14:06:42 +0100
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
	<7c3dvuF25o0t6U1@mid.uni-berlin.de>
Message-ID: <h3hvt2$16t$1@gemini.csx.cam.ac.uk>

Diez B. Roggisch wrote:

> Yep, you are:
> 
> "())))((("
> 
> is certainly not "well parenthized".

Thanks for that!

-- 
Jeremy Sanders
http://www.jeremysanders.net/



From deets at nospam.web.de  Tue Jul 14 09:07:20 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 14 Jul 2009 15:07:20 +0200
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
Message-ID: <7c3dvuF25o0t6U1@mid.uni-berlin.de>

Jeremy Sanders wrote:

> candide wrote:
> 
>> I'm trying to implement in Python a function testing if an expression is
>> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
>> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
>> 
>> My code follows at the end.
>> 
>> If you have a better algorithm or a better Python code (I'm a beginner in
>> the Python world), don't hesitate ...
> 
> Don't you want to just test that the number of "("s equals the number of
> ")"s or am I missing the point?

Yep, you are:

"())))((("

is certainly not "well parenthized".

Diez


From dns4 at cornell.edu  Tue Jul 14 09:08:12 2009
From: dns4 at cornell.edu (David Smith)
Date: Tue, 14 Jul 2009 09:08:12 -0400
Subject: Python code for testing well parenthesized expression
In-Reply-To: <h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
Message-ID: <h3hvvu$o32$1@ruby.cit.cornell.edu>

Jeremy Sanders wrote:
> candide wrote:
> 
>> I'm trying to implement in Python a function testing if an expression is
>> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
>> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
>>
>> My code follows at the end.
>>
>> If you have a better algorithm or a better Python code (I'm a beginner in
>> the Python world), don't hesitate ...
> 
> Don't you want to just test that the number of "("s equals the number of 
> ")"s or am I missing the point?
> 
>>>> a='aAAA(bbb(cc)))'
>>>> a.count('(') == a.count(')')
> 
> Jeremy
> 

Using straight counting, )z))ab(c(ew( would be well parenthesized.  I
suspect a better way would be to iterate over the string using a balance
counter that increases 1 for every open, decreases 1 for every close.  A
negative balance at any moment would indicate an error as well as an
ending balance greater than 0.

--David


From martin.hellwig at dcuktec.org  Tue Jul 14 09:14:48 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 14 Jul 2009 14:14:48 +0100
Subject: Python code for testing well parenthesized expression
In-Reply-To: <YvGdnSP5s64-H8HXnZ2dnUVZ8u2dnZ2d@bt.com>
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<YvGdnSP5s64-H8HXnZ2dnUVZ8u2dnZ2d@bt.com>
Message-ID: <nIOdnRvpW_1UGcHXnZ2dnUVZ8sqdnZ2d@bt.com>

Martin P. Hellwig wrote:
> candide wrote:
> To add to your implementations; a readable version:
> 
> +++file parantheses.py+++
> """Parentheses Module Test"""
> 
> def parentheses_are_paired(input_string):
>     "Check if 'input_string' contains paired parentheses, if so return 
> True."
>     parenthesis_count = 0
>     parenthesis_open = '('
>     parenthesis_close = ')'
> 
>     for character in input_string:
>         if character == parenthesis_open:
>             parenthesis_count += 1
>         elif character == parenthesis_close:
>             parenthesis_count -= 1
> 
> 
>     if parenthesis_count == 0:
>         return(True)
>     else:
>         if parenthesis_count < 0:
>             error_text = 'More closing parantheses than opening ones'
> 
>         elif parenthesis_count > 0:
>             error_text = 'More opening parantheses than closing ones'
> 
>         raise(ValueError(error_text))
> 
> if __name__ == '__main__':
>     TEST_TRUE = 'zx4er(1(er(Yy)ol)ol)ik'
>     TEST_ERROR = 'zx(4er(1(er(Yy)ol)ol)ik'
> 
>     print(parentheses_are_paired(TEST_TRUE))
> 
>     try:
>         print(parentheses_are_paired(TEST_ERROR))
>     except(ValueError):
>         print(False)
> 
> ---file parantheses.py---
> 

However as Mr. Roggisch commented this wouldn't check if it is on the 
right spot, by moving the check that at any time you can not have more 
closing ones than opening ones within the loop you will get those 
exceptions too.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From sjmachin at lexicon.net  Tue Jul 14 09:14:50 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 13:14:50 +0000 (UTC)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <loom.20090714T125851-382@post.gmane.org>

candide <candide <at> free.invalid> writes:

> # The obvious iterative version
> def i(s):
>     op = 0 # op : open parenthesis
>     for k in range(len(s)):
>         op += (s[k] == '(') - (s[k] == ')')
>         if op < 0: break
>     return op
> 

E: H c, w t P.
F: A c, b ? P.

Suggested better code:

def iterative(string):
    paren_count = 0
    for char in string:
        paren_count += (char == '(') - (char == ')')
        if paren_count < 0: break
    return paren_count

You don't need the other versions :-)

Try an iterative version of checking that () [] and {}
are balanced and nested appropriately.

Cheers,
John



From sjmachin at lexicon.net  Tue Jul 14 09:17:48 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 06:17:48 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk> 
	<h3hvvu$o32$1@ruby.cit.cornell.edu>
Message-ID: <e8195ead-f733-4107-a98b-b000170968d4@y28g2000prd.googlegroups.com>

On Jul 14, 11:08?pm, David Smith <d... at cornell.edu> wrote:
> Jeremy Sanders wrote:
> > candide wrote:
>
> >> I'm trying to implement in Python a function testing if an expression is
> >> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
> >> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
>
> >> My code follows at the end.
>
> >> If you have a better algorithm or a better Python code (I'm a beginner in
> >> the Python world), don't hesitate ...
>
> > Don't you want to just test that the number of "("s equals the number of
> > ")"s or am I missing the point?
>
> >>>> a='aAAA(bbb(cc)))'
> >>>> a.count('(') == a.count(')')
>
> > Jeremy
>
> Using straight counting, )z))ab(c(ew( would be well parenthesized. ?I
> suspect a better way would be to iterate over the string using a balance
> counter that increases 1 for every open, decreases 1 for every close. ?A
> negative balance at any moment would indicate an error as well as an
> ending balance greater than 0.
>
> --David

Ummm isn't that the OP's first function?


From Scott.Daniels at Acm.Org  Tue Jul 14 09:19:37 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 06:19:37 -0700
Subject: Efficient binary search tree stored in a flat array?
In-Reply-To: <m2r5wjzcr7.fsf@cs.uu.nl>
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
Message-ID: <xcadneiIYYK1GcHXnZ2dnUVZ_qadnZ2d@pdx.net>

Piet van Oostrum wrote:
>>>>>> Douglas Alan <darkwater42 at gmail.com> (DA) wrote:
> 
>> DA> On Jul 13, 3:57 pm, a... at pythoncraft.com (Aahz) wrote:
>>>> Still, unless your list is large (more than thousands of elements),
>>>> that's the way you should go.  See the bisect module.  Thing is, the
>>>> speed difference between C and Python means the constant for insertion
>>>> and deletion is very very small relative to bytecode speed.  Keep in
>>>> mind that Python's object/binding model means that you're shuffling
>>>> pointers in the list rather than items.
> 
>> DA> Thank you. My question wasn't intended to be Python specific, though.
>> DA> I am just curious for purely academic reasons about whether there is
>> DA> such an algorithm. All the sources I've skimmed only seem to the
>> DA> answer the question via omission. Which is kind of strange, since it
>> DA> seems to me like an obvious question to ask.

It may well be that there is no good simple solution, and people avoid
writing about non-existent algorithms.  I certainly cannot imagine
trying to write an article that carefully covered ideas which don't
have well-studied data structures available, and calling them out
only to say, "we don't know how to do this well."  If such an algorithm
were simple and obvious, I dare say you'd be taught about it around the
time you learn binary search.

> Of course you can take any BST algorithm and replace pointers by indices
> in the array and allocate new elements in the array. But then you need
> array elements to contain the indices for the children explicitely.

And you loower your locality of reference (cache-friendliness).
Note the insert in Python, for example, is quite cache-friendly.

--Scott David Daniels
Scott.Daniels at Acm.Org


From aaron.watters at gmail.com  Tue Jul 14 09:23:23 2009
From: aaron.watters at gmail.com (Aaron Watters)
Date: Tue, 14 Jul 2009 06:23:23 -0700 (PDT)
Subject: WHIFF 0.4 += repoze.who authentication + menus + calculator + docs.
Message-ID: <1209aa77-c58c-4daf-a0f7-74f479ca59c8@f30g2000vbf.googlegroups.com>

WHIFF (WSGI HTTP Integrated Filesystem Frames) 0.4 released.

The new WHIFF 0.4 release linked from

    http://whiff.sourceforge.net

includes the following enhancements:

Built in support for repoze.who based authentication
(from http://static.repoze.org/whodocs/ ) + tutorial
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1100_1500.who .

AJAX calculator demo and tutorial:
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1100_1400.calc .

Built in drop-down menu support and tutorial:
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1100_1300.menus .

Some subtle but important bug fixes, including a thread
race condition bug fix.  Auto-reload support.

Also documentation improvements: particularly
for standard middleware
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1200_1400.stdMiddleware

What is WHIFF?

WHIFF is a collection of support services for Python WSGI
applications which allows applications to be composed
by "dropping" dynamic pages into container directories.
This mode of development will be familiar to developers
who have created PHP applications, vanilla CGI scripts,
Apache/modpy Publisher applications, JSP pages, or
static web content.

The WHIFF implementation significantly generalizes the
"drop in" paradigm to support WSGI middleware components
and application fragments as well as stand-alone pages.

WHIFF provides other services in addition to supporting
"drop in" components, such as managed application
resources.

I created WHIFF to address complexity issues I
encounter when creating and fixing sophisticated
Web applications which include complex database
interactions and dynamic features such as AJAX
(Asynchronous Javascript And XML).

Project home page:
   http://whiff.sourceforge.net .
Documentation index:
   http://aaron.oirt.rutgers.edu/myapp/docs/W.intro .

I hope you like it!

   -- Aaron Watters

===
% ping elvis
elvis is alive


From sjmachin at lexicon.net  Tue Jul 14 09:26:38 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 13:26:38 +0000 (UTC)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<c3635e15-37b1-431d-aeef-7b90f29a9c3d@f10g2000vbf.googlegroups.com>
Message-ID: <loom.20090714T132012-442@post.gmane.org>

Adrian Dziubek <adrian.dziubek <at> gmail.com> writes:


> In the i() there should be "return
> op == 0" on the end.

Hard to tell. In the absence of any docs, we have to resort to divination on the
function name :-P ... is "i" short for "iterative" or "imbalanced"?





From l.lensgraf at gmail.com  Tue Jul 14 09:49:38 2009
From: l.lensgraf at gmail.com (DrLeif)
Date: Tue, 14 Jul 2009 06:49:38 -0700 (PDT)
Subject: PDF: finding a blank image
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
	<h7udnSUJcYlyIsbXnZ2dnUVZ_vWdnZ2d@pdx.net>
Message-ID: <736570b5-c315-4eb2-99d1-5de7f05c26d0@l28g2000vba.googlegroups.com>

On Jul 13, 6:22?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> DrLeif wrote:
> > I have about 6000 PDF files which have been produced using a scanner
> > with more being produced each day. ?The PDF files contain old paper
> > records which have been taking up space. ? The scanner is set to
> > detect when there is information on the backside of the page (duplex
> > scan). ?The problem of course is it's not the always reliable and we
> > wind up with a number of PDF files containingblankpages.
>
> > What I would like to do is have python detect a "blank" pages in a PDF
> > file and remove it. ?Any suggestions?
>
> I'd check into ReportLab's commercial product, it may well be easily
> capable of that. ?If no success, you might contact PJ at Groklaw, she
> has dealt with a _lot_ of PDFs (and knows people who deal with PDFs
> in bulk).
>
> --Scott David Daniels
> Scott.Dani... at Acm.Org



From aahz at pythoncraft.com  Tue Jul 14 09:54:07 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 06:54:07 -0700
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <h3i2lv$8em$1@panix3.panix.com>

In article <mailman.3048.1247462046.8015.python-list at python.org>,
Vincent Gulinao  <vincent.gulinao at gmail.com> wrote:
>
>lst = list()
>
>while True:
>	if len(lst) == SOME_NUMBER:
>		return lst
>
>Q2: operating on list from threads (mostly appends) must be safe,
>right (synchronization)?

What do you mean by "safe"?  Python certainly won't crash, but there's
no guarantee that the list will be consistent from *your* perspective.
Consider what happens if len(lst) == SOME_NUMBER - 1 and some other part
of your code adds two elements to lst.  You'll skip right over your if
condition.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From aahz at pythoncraft.com  Tue Jul 14 09:55:37 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 06:55:37 -0700
Subject: compilation problem of python on AIX 6.1
References: <51c556a8-7277-474d-821f-190adf155c75@f16g2000vbf.googlegroups.com>
Message-ID: <h3i2op$5if$1@panix3.panix.com>

In article <51c556a8-7277-474d-821f-190adf155c75 at f16g2000vbf.googlegroups.com>,
Amit  <amit.kumar.iitr at gmail.com> wrote:
>
>THen I decided to compile python 2.5.4 on my AIX box. I downloaded the
>python source code from www.python.org and tried to compile on my AIX
>both using gcc.
>
>	case $MAKEFLAGS in  *-s*)  CC='gcc -pthread' LDSHARED='./Modules/
>ld_so_aix gcc -pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -
>fwrapv -O3 -Wall -Wstrict-prototypes' ./python -E ./setup.py -q
>build;;  *)  CC='gcc -pthread' LDSHARED='./Modules/ld_so_aix gcc -
>pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -fwrapv -O3 -Wall -
>Wstrict-prototypes' ./python -E ./setup.py build;;  esac
>running build
>running build_ext
>building 'bz2' extension
>gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
>Wstrict-prototypes -I. -I/avre/Python-2.5.4/./Include -I. -IInclude -
>I./Include -I/avre/Python-2.5.4/Include -I/avre/Python-2.5.4 -c /avre/
>Python-2.5.4/Modules/bz2module.c -o build/temp.aix-6.1-2.5/avre/
>Python-2.5.4/Modules/bz2module.o
>building '_tkinter' extension
>./Modules/ld_so_aix gcc -pthread -bI:Modules/python.exp build/
>temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/_tkinter.o build/
>temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/tkappinit.o -L/usr/X11/lib -
>ltk8.4 -ltcl8.4 -lX11 -o build/lib.aix-6.1-2.5/_tkinter.so
>*** WARNING: renaming "_tkinter" since importing it failed: 	0509-022
>Cannot load module build/lib.aix-6.1-2.5.
>	0509-026 System error: A file or directory in the path name does not
>exist.

This looks like a generic AIX compilation error finding system libraries;
you probably will get better results from asking on an AIX forum.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From fatkinson at mishmash.com  Tue Jul 14 09:56:01 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Tue, 14 Jul 2009 06:56:01 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com>
Message-ID: <hi3p551ikld7d00c3dvs1vhkmnjgg8ffcn@4ax.com>

On Tue, 14 Jul 2009 05:41:40 GMT, Tim Harig <usernet at ilthio.net>
wrote:

>On 2009-07-14, Fred Atkinson <fatkinson at mishmash.com> wrote:
>> 	The one thing I really dislike about Python over PHP is that
>> Python can usually only appear in the cgi directory (unless other
>> arragements are made with your hosting provider or if you reconfigure
>> Apache on your own server if you have your own).  With PHP, I can put
>> them in any folder on my Web site without any problem.  
>
>That is a server configuration and has nothing to do with Python directly.

Agreed, it doesn't.  But if my hosting provider won't change it, I'm
stuck with it.  

Regards, 



 Fred 


From fatkinson at mishmash.com  Tue Jul 14 09:58:58 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Tue, 14 Jul 2009 06:58:58 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<e47c89c6-3e16-48c1-b257-c53642fd9c0b@13g2000prl.googlegroups.com>
Message-ID: <5k3p5514u11kldk56vjgpop4jp90hf3o89@4ax.com>

On Mon, 13 Jul 2009 23:54:11 -0700 (PDT), alex23 <wuwei23 at gmail.com>
wrote:

>Fred Atkinson <fatkin... at mishmash.com> wrote:
>> ? ? ? ? I wish the Python site was as well written as the PHP site. On
>> the PHP site, I can look up a command and they show not only the docs
>> on that command but a list of all other commands associated with it. ?
>
>Hey Fred,
>
>My problem is the complete opposite, I wish I could as easily
>interrogate objects in PHP about their behaviour as I can Python :)
>
>In case you're not familiar with this, you can see what methods are
>attached to an object using the intepreter via dir() and see the
>associated docstring for them via help(). Try looking at 'dir(str)'
>for a list of methods that strings recognise, then 'help(str.join)' to
>see the help on join.
>
>This is such a handy ability to have that I miss this casual
>introspection in everything else in which I'm required to develop.
>
>Hope this helps.

	I appreciate the information.  I'm halfway through a course in
PHP and Python.  We are given assignments and we have to write the
assignment in both languages.  

	I'll take a look at that as I work on this week's assignment
(I've only got a month to finish the course but I can probably take
some time to look at this.  

	Regards, 




					Fred 


From phonky at europe.com  Tue Jul 14 10:03:16 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 16:03:16 +0200
Subject: one-time factory in python for an experienced java guy
Message-ID: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>

Hi

I have searched all over and haven't found the solution
for my problem yet. I am new to python, and all the time realize I
do program python in java, which is not great.

Besides being a real-life problem, I want to
solve it as elegant as I can, using it to
also learn about python (I know I could just
hack something easy for now).

That's what I want to do.

I have an Account class.
An Account instance has to get an account number.
On instance creation, I want the account number to
be generated (I don't want callers to pass
the account # to ensure uniqueness):

class Account(object):
	def __init__(self, holder):
         	self.__accountnumber = self.__generate_account_number()

Now, I do not know yet how the account number scheme looks like.
For now, I just want to have an incremental number; later,
when going to production, we'll need the proper one.

Furthermore, as we plan to distribute the package, we want
to allow custom account numbering schemes. Thus, customers
should be able to plug in their own AccountNumberGenerator implementation.

For now, I have a generators.py module.

I have an AccountNumberGenerator base class,
all subclasses should implement "generate".

I have an IncrementalGenerator subclass.

So for now, I need to instantiate IncrementalGenerator,
allowing for a future module to plugin their own generator.

Any suggestions on how to do this?
Thanks so much!!!!


From l.lensgraf at gmail.com  Tue Jul 14 10:04:16 2009
From: l.lensgraf at gmail.com (DrLeif)
Date: Tue, 14 Jul 2009 07:04:16 -0700 (PDT)
Subject: PDF: finding a blank image
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
	<h7udnSUJcYlyIsbXnZ2dnUVZ_vWdnZ2d@pdx.net>
Message-ID: <6ba293b7-bba4-4d7b-ba3b-fb7901a2ea7d@e18g2000vbe.googlegroups.com>

On Jul 13, 6:22?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> DrLeif wrote:
> > I have about 6000 PDF files which have been produced using a scanner
> > with more being produced each day. ?The PDF files contain old paper
> > records which have been taking up space. ? The scanner is set to
> > detect when there is information on the backside of the page (duplex
> > scan). ?The problem of course is it's not the always reliable and we
> > wind up with a number of PDF files containingblankpages.
>
> > What I would like to do is have python detect a "blank" pages in a PDF
> > file and remove it. ?Any suggestions?
>
> I'd check into ReportLab's commercial product, it may well be easily
> capable of that. ?If no success, you might contact PJ at Groklaw, she
> has dealt with a _lot_ of PDFs (and knows people who deal with PDFs
> in bulk).
>
> --Scott David Daniels
> Scott.Dani... at Acm.Org


Thanks everyone for the quick reply.

I had considered using ReportLab however, was uncertain about it's
ability to detect a blank page.

Scott, I'll drop an email to ReportLab and PJ....

Thanks again,
DrLeif


From jjposner at optimum.net  Tue Jul 14 10:07:52 2009
From: jjposner at optimum.net (John Posner)
Date: Tue, 14 Jul 2009 10:07:52 -0400
Subject: Tkinter / Entry widget problem
In-Reply-To: <mailman.11278.1247575203.8014.python-list@python.org>
References: <mailman.11278.1247575203.8014.python-list@python.org>
Message-ID: <4A5C9138.2020502@optimum.net>


> Andras Szabo wrote:
>
>   
>> Hello. I searched the archives but couldn't find a solution to a
>> problem related to the Entry widget in Tkinter.
>>
>> When creating a pop-up window in an app, which contains an Entry
>> widget, I want this widget to contain some default string, to have all
>> this default string selected (as if the user had manually selected
>> everything), and to have the focus transferred to this widget.
>>
>> (The idea is then that if the window pops up, the user won't have to
>> click or press Tab any more before being able to type what is needed
>> in the textbox, overwriting what is written there already.)
>>
>> I thought this might be the way to go:
>>
>> entrybox=Entry(toplevel_parent_window)
>> entrybox.insert(0,"Some default string")
>> entrybox.select_range(0,END)
>> entrybox.focus_set()
>> entrybox.pack()
>>
>> But it doesn't seem to work - the focus is not transferred to the
>> Entry widget, and the text does not appear to be selected (even though
>> after this entrybox.selection_present() returns True).
>>
>> What am I doing wrong?
>>     
>
> Nothing, I would think. Can you post a minimal runnable example?
>
> Peter

This works for me, on Windows and Linux:

  from Tkinter import *

  rt = Tk()
  rt.title("root window")
  pop = Toplevel()
  pop.title("second window")

  entrybox=Entry(pop)
  entrybox.insert(0,"Some default string")
  entrybox.select_range(0,END)
  entrybox.focus_set()
  entrybox.pack()

  rt.withdraw()
  rt.mainloop()


On Win/XP SP3:

  > python
  Python 2.6.1 (r261:67517, Dec  4 2008, 16:51:00) [MSC v.1500 32 bit
   (Intel)] on   win32
  Type "help", "copyright", "credits" or "license" for more information.
  >>> import Tkinter
  >>> Tkinter.TkVersion
  8.5
  >>> Tkinter.TclVersion
  8.5

On Ubuntu Linux (Ubu-SL 2.6.27.14-generic):

  $ python
  Python 2.6.1 (r261:67515, Jan  9 2009, 19:06:23)
  [GCC 4.3.2] on linux2
  Type "help", "copyright", "credits" or "license" for more information.
  >>> import Tkinter
  >>> Tkinter.TkVersion
  8.4000000000000004
  >>> Tkinter.TclVersion
  8.4000000000000004


-John



From piet at cs.uu.nl  Tue Jul 14 10:10:06 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 16:10:06 +0200
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com>
	<hi3p551ikld7d00c3dvs1vhkmnjgg8ffcn@4ax.com>
Message-ID: <m2ljmrz77l.fsf@cs.uu.nl>

>>>>> Fred Atkinson <fatkinson at mishmash.com> (FA) wrote:

>FA> On Tue, 14 Jul 2009 05:41:40 GMT, Tim Harig <usernet at ilthio.net>
>FA> wrote:

>>> On 2009-07-14, Fred Atkinson <fatkinson at mishmash.com> wrote:
>>>> The one thing I really dislike about Python over PHP is that
>>>> Python can usually only appear in the cgi directory (unless other
>>>> arragements are made with your hosting provider or if you reconfigure
>>>> Apache on your own server if you have your own).  With PHP, I can put
>>>> them in any folder on my Web site without any problem.  
>>> 
>>> That is a server configuration and has nothing to do with Python directly.

>FA> Agreed, it doesn't.  But if my hosting provider won't change it, I'm
>FA> stuck with it.  

That's a good reason to dislike your hosting provider, not a good reason
to dislike Python.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From stefan_ml at behnel.de  Tue Jul 14 10:27:48 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 14 Jul 2009 16:27:48 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
Message-ID: <4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>

phonky wrote:
> class Account(object):
>     def __init__(self, holder):
>             self.__accountnumber = self.__generate_account_number()
> 
> Now, I do not know yet how the account number scheme looks like.
> For now, I just want to have an incremental number; later,
> when going to production, we'll need the proper one.

Use a global variable in the module.

Stefan


From http  Tue Jul 14 10:33:26 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 07:33:26 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7xzlb7wczt.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:

> phonky wrote:
> > class Account(object):
> >     def __init__(self, holder):
> >             self.__accountnumber = self.__generate_account_number()
> > 
> > Now, I do not know yet how the account number scheme looks like.
> > For now, I just want to have an incremental number; later,
> > when going to production, we'll need the proper one.
> 
> Use a global variable in the module.

Yuch!  Don't use a global.  Try something like:

    import itertools

    class Account(object):
       def __init__(self, holder, gen=itertools.count()):
          self.__accountnumber = gen.next()


From phonky at europe.com  Tue Jul 14 10:34:30 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 16:34:30 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>

Stefan, thanks first of all

> Use a global variable in the module.

I have an account_number_generator variable in the module,
I got that hint from searching the web.

But where my stubborn java mind doesn't release me:
what does the variable contain? Do I create the actual
IncrementalGenerator object there? Or the super class?
Or just a string, which a factory method takes to
create the actual object?

What I especially don't get:
How will an external module overwrite that variable?

I fail to see, python being interpreted, how I can ensure
that a future module is being executed later, thus
overwriting the variable.

Thanks again.



From newport at freemail.hu  Tue Jul 14 10:38:42 2009
From: newport at freemail.hu (Andras Szabo)
Date: Tue, 14 Jul 2009 17:38:42 +0300
Subject: Tkinter / Entry widget problem
In-Reply-To: <4A5C9138.2020502@optimum.net>
References: <mailman.11278.1247575203.8014.python-list@python.org>
	<4A5C9138.2020502@optimum.net>
Message-ID: <A250B4AC-C159-4919-BCE4-14747CC2DBD6@freemail.hu>

So it's either that I use Python 2.5.1, or that I use it on a Mac.  
(John, your code still doesn't work the way it's supposed to here.) I  
guess I'll upgrade to 2.6.1 and see if it makes a difference. (The  
Tkinter/Tcl versions are the same for me.) Thanks for your help.

andras

On Jul 14, 2009, at 5:07 PM, John Posner wrote:

>
>> Andras Szabo wrote:
>>
>>
>>> Hello. I searched the archives but couldn't find a solution to a
>>> problem related to the Entry widget in Tkinter.
>>>
>>> When creating a pop-up window in an app, which contains an Entry
>>> widget, I want this widget to contain some default string, to have  
>>> all
>>> this default string selected (as if the user had manually selected
>>> everything), and to have the focus transferred to this widget.
>>>
>>> (The idea is then that if the window pops up, the user won't have to
>>> click or press Tab any more before being able to type what is needed
>>> in the textbox, overwriting what is written there already.)
>>>
>>> I thought this might be the way to go:
>>>
>>> entrybox=Entry(toplevel_parent_window)
>>> entrybox.insert(0,"Some default string")
>>> entrybox.select_range(0,END)
>>> entrybox.focus_set()
>>> entrybox.pack()
>>>
>>> But it doesn't seem to work - the focus is not transferred to the
>>> Entry widget, and the text does not appear to be selected (even  
>>> though
>>> after this entrybox.selection_present() returns True).
>>>
>>> What am I doing wrong?
>>>
>>
>> Nothing, I would think. Can you post a minimal runnable example?
>>
>> Peter
>
> This works for me, on Windows and Linux:
>
> from Tkinter import *
>
> rt = Tk()
> rt.title("root window")
> pop = Toplevel()
> pop.title("second window")
>
> entrybox=Entry(pop)
> entrybox.insert(0,"Some default string")
> entrybox.select_range(0,END)
> entrybox.focus_set()
> entrybox.pack()
>
> rt.withdraw()
> rt.mainloop()
>
>
> On Win/XP SP3:
>
> > python
> Python 2.6.1 (r261:67517, Dec  4 2008, 16:51:00) [MSC v.1500 32 bit
>  (Intel)] on   win32
> Type "help", "copyright", "credits" or "license" for more information.
> >>> import Tkinter
> >>> Tkinter.TkVersion
> 8.5
> >>> Tkinter.TclVersion
> 8.5
>
> On Ubuntu Linux (Ubu-SL 2.6.27.14-generic):
>
> $ python
> Python 2.6.1 (r261:67515, Jan  9 2009, 19:06:23)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> >>> import Tkinter
> >>> Tkinter.TkVersion
> 8.4000000000000004
> >>> Tkinter.TclVersion
> 8.4000000000000004
>
>
> -John
>
>



From http  Tue Jul 14 10:40:52 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 07:40:52 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
Message-ID: <7xab37l43v.fsf@ruckus.brouhaha.com>

phonky <phonky at europe.com> writes:
> But where my stubborn java mind doesn't release me: what does the
> variable contain? Do I create the actual IncrementalGenerator object
> there? Or the super class?  Or just a string, which a factory method
> takes to create the actual object?

Ugh, just forget everything you ever knew about java.  Do some Zen
exercises to erase your mind.  Then read a Python tutorial as if
you're starting from nothing.


From contact at xavierho.com  Tue Jul 14 10:52:55 2009
From: contact at xavierho.com (Xavier Ho)
Date: Tue, 14 Jul 2009 22:52:55 +0800
Subject: Why does extend() fail in this case, and what am I doing wrong?
Message-ID: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>

Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
The code is run at: http://codepad.org/wgLU4JZh

class A():
    def __init__(self):
        self.n = [1, 2, 3, 4, 5]

a = A()
print a.n
print a.n.extend([6, 7, 8, 9])

#Output:
#[1, 2, 3, 4, 5]
#None

I really don't know, but I'm probably missing something. Any pointers would
be great.

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/716ef38c/attachment.html>

From phonky at europe.com  Tue Jul 14 10:55:56 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 16:55:56 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <7xab37l43v.fsf@ruckus.brouhaha.com>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
Message-ID: <23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>

Thanks Paul,

> Ugh, just forget everything you ever knew about java.  Do some Zen
> exercises to erase your mind.  Then read a Python tutorial as if
> you're starting from nothing.

Yeah, surely right, but easier said than done...
I'm working on it.

Taking your example.

import itertools

     class Account(object):
        def __init__(self, holder, gen=itertools.count()):
           self.__accountnumber = gen.next()

If you consider my python illiteracy,

"itertools.count(): Make an iterator that returns consecutive integers 
starting with n"

to me that sounds like that solves the increment issue, but what about
future modules wanting to plug in a different
numbering format, e.g. 205434.1234 or whatever?




From tn.pablo at gmail.com  Tue Jul 14 11:07:29 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Tue, 14 Jul 2009 10:07:29 -0500
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
Message-ID: <fdd00b510907140807n19110d2bo2066c335c3926939@mail.gmail.com>

This has been asked extensively before, here and elsewhere.

On Tue, Jul 14, 2009 at 09:52, Xavier Ho<contact at xavierho.com> wrote:
> Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
> The code is run at: http://codepad.org/wgLU4JZh
>
> class A():
> ??? def __init__(self):
> ??????? self.n = [1, 2, 3, 4, 5]
>
> a = A()
> print a.n
> print a.n.extend([6, 7, 8, 9])
>
> #Output:
> #[1, 2, 3, 4, 5]
> #None
>
> I really don't know, but I'm probably missing something. Any pointers would
> be great.
>
> Best regards,
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>



-- 
Pablo Torres N.


From mabdelkader at gmail.com  Tue Jul 14 11:07:59 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Tue, 14 Jul 2009 11:07:59 -0400
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch> 
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch> 
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <148918f0907140807i3b31f9b0u94fecf309eec5cdc@mail.gmail.com>

What Paul was trying to elaborate on is that have your customers or whomever
will use this implement their own generator protocol to generate whatever
number format they need. Paul just gave you an example with
itertools.count(), where it is an infinite generator that yields count+1
every time.

Read up on the iterator protocol, have your customers pass in a generator to
establish their own formats.
http://docs.python.org/library/stdtypes.html#iterator-types

This is much more elegant than AbstractCustomerRandomFormatGenerator..etc
which is what the reference to "erase everything from Java" is attempting to
relate.

--
mahmoud mack abdelkader
python powered
http://blog.mahmoudimus.com/
mahmoud at linux.com


On Tue, Jul 14, 2009 at 10:55 AM, phonky <phonky at europe.com> wrote:

> Thanks Paul,
>
>  Ugh, just forget everything you ever knew about java.  Do some Zen
>> exercises to erase your mind.  Then read a Python tutorial as if
>> you're starting from nothing.
>>
>
> Yeah, surely right, but easier said than done...
> I'm working on it.
>
> Taking your example.
>
> import itertools
>
>    class Account(object):
>       def __init__(self, holder, gen=itertools.count()):
>          self.__accountnumber = gen.next()
>
> If you consider my python illiteracy,
>
> "itertools.count(): Make an iterator that returns consecutive integers
> starting with n"
>
> to me that sounds like that solves the increment issue, but what about
> future modules wanting to plug in a different
> numbering format, e.g. 205434.1234 or whatever?
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/d8becbaf/attachment.html>

From python at mrabarnett.plus.com  Tue Jul 14 11:13:43 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 16:13:43 +0100
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
Message-ID: <4A5CA0A7.7090800@mrabarnett.plus.com>

Xavier Ho wrote:
> Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
> The code is run at: http://codepad.org/wgLU4JZh
> 
> class A():
>     def __init__(self):
>         self.n = [1, 2, 3, 4, 5]
>        
> a = A()
> print a.n
> print a.n.extend([6, 7, 8, 9])
> 
> #Output:
> #[1, 2, 3, 4, 5]
> #None
> 
> I really don't know, but I'm probably missing something. Any pointers 
> would be great.
> 
The extend() method modifies the list in-place and returns None. Try
printing a.n after extending.


From http  Tue Jul 14 11:14:18 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 08:14:18 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <7xzlb7fgad.fsf@ruckus.brouhaha.com>

phonky <phonky at europe.com> writes:
> "itertools.count(): Make an iterator that returns consecutive integers
> starting with n"
> 
> to me that sounds like that solves the increment issue, but what about
> future modules wanting to plug in a different
> numbering format, e.g. 205434.1234 or whatever?

You'd write a different generator for that, and use it instead of
itertools.count.  E.g. (untested):

  def different_gen():
      a  = 201593.0768                  # initial number
      while True:
         yield '%.04f'% a
         a += 123.4567                  # increase in increments of this much


From __peter__ at web.de  Tue Jul 14 11:20:03 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 14 Jul 2009 17:20:03 +0200
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <h3i7ms$n4c$01$1@news.t-online.com>

phonky wrote:

> Thanks Paul,
> 
>> Ugh, just forget everything you ever knew about java.  Do some Zen
>> exercises to erase your mind.  Then read a Python tutorial as if
>> you're starting from nothing.
> 
> Yeah, surely right, but easier said than done...
> I'm working on it.
> 
> Taking your example.
> 
> import itertools
> 
>      class Account(object):
>         def __init__(self, holder, gen=itertools.count()):
>            self.__accountnumber = gen.next()
> 
> If you consider my python illiteracy,
> 
> "itertools.count(): Make an iterator that returns consecutive integers
> starting with n"
> 
> to me that sounds like that solves the increment issue, but what about
> future modules wanting to plug in a different
> numbering format, e.g. 205434.1234 or whatever?

In that case you may want to stick with the class attribute:

>>> class Account(object):
...     def __init__(self):
...             self.account = self.next_account()
...     def __str__(self):
...             return "Account(number=%r)" % self.account
...     __repr__ = __str__
...
>>> from itertools import count
>>> Account.next_account = count(42).next
>>> a = Account()
>>> b = Account()
>>> a, b
(Account(number=42), Account(number=43))
>>> from uuid import uuid1
>>> Account.next_account = staticmethod(uuid1)
>>> c = Account()
>>> d = Account()
>>> c, d
(Account(number=UUID('b0f8dfc6-7087-11de-be16-001d923f29c5')), 
Account(number=UUID('b310c90e-7087-11de-be16-001d923f29c5')))

You can plug in arbitrary callables at runtime. The only complication I can 
see is that you may have to wrap them into a staticmethod to prevent python 
from passing the self reference. You can avoid that if you just use a global 
instead:

# account.py
next_account = ...
class Account(object):
   def __init__(self): self.number = next_account()

You can then set the factory elsewhere

# main.py
import account
account.next_account = ...
a = Account()

In general in python we like to keep simple things simple rather than 
creating a huge bureaucracy.

Peter



From ml at well-adjusted.de  Tue Jul 14 11:20:13 2009
From: ml at well-adjusted.de (Jochen Schulz)
Date: Tue, 14 Jul 2009 17:20:13 +0200
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
Message-ID: <20090714152012.GY31378@wasteland.homelinux.net>

Xavier Ho:
>
> Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
-- snip
> print a.n.extend([6, 7, 8, 9])

extend doesn't fail. It just returns None and extends the list in place.

In [1]: l = [1, 2, 3]

In [2]: l.extend([4, 5, 6])

In [3]: l
Out[3]: [1, 2, 3, 4, 5, 6]


J.
-- 
When I get home from the supermarket I don't know what to do with all the
plastic.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/a85f7b98/attachment.sig>

From aahz at pythoncraft.com  Tue Jul 14 11:24:14 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 08:24:14 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <h3i7uu$9oe$1@panix3.panix.com>

In article <23406$4a5c9c7d$d9a2f023$27926 at news.hispeed.ch>,
phonky  <phonky at europe.com> wrote:
>
>import itertools
>
>     class Account(object):
>        def __init__(self, holder, gen=itertools.count()):
>           self.__accountnumber = gen.next()
>
>If you consider my python illiteracy,
>
>"itertools.count(): Make an iterator that returns consecutive integers 
>starting with n"
>
>to me that sounds like that solves the increment issue, but what about
>future modules wanting to plug in a different
>numbering format, e.g. 205434.1234 or whatever?

Here's what I would do:

class Account:
    gen = itertools.count
    gen_instance = None

    def __init__(self, holder):
        if self.gen_instance is None:
            self.__class__.gen_instance = self.gen()
        self._account = self.gen_instance()

Notice that I'm using only a single underscore for ``_account`` to make
inheritance simpler, and I'm using ``self`` to access class attributes
*except* when I need to *set* the class attribute, which requires
``self.__class__``.

Now anyone who wants to change the generator can simply do
module.Account.gen = other_gen 
and it will work as long as no Account() instances have been created (you
don't want the generator to change mid-stream, right?).
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From pdpinheiro at gmail.com  Tue Jul 14 11:35:40 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 14 Jul 2009 08:35:40 -0700 (PDT)
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
Message-ID: <f83064a1-49bd-4133-980c-ab847a0b3bdf@n30g2000vba.googlegroups.com>

On Jul 14, 3:03?pm, phonky <pho... at europe.com> wrote:
> Hi
>
> I have searched all over and haven't found the solution
> for my problem yet. I am new to python, and all the time realize I
> do program python in java, which is not great.
>
> Besides being a real-life problem, I want to
> solve it as elegant as I can, using it to
> also learn about python (I know I could just
> hack something easy for now).
>
> That's what I want to do.
>
> I have an Account class.
> An Account instance has to get an account number.
> On instance creation, I want the account number to
> be generated (I don't want callers to pass
> the account # to ensure uniqueness):
>
> class Account(object):
> ? ? ? ? def __init__(self, holder):
> ? ? ? ? ? ? ? ? self.__accountnumber = self.__generate_account_number()
>
> Now, I do not know yet how the account number scheme looks like.
> For now, I just want to have an incremental number; later,
> when going to production, we'll need the proper one.
>
> Furthermore, as we plan to distribute the package, we want
> to allow custom account numbering schemes. Thus, customers
> should be able to plug in their own AccountNumberGenerator implementation.
>
> For now, I have a generators.py module.
>
> I have an AccountNumberGenerator base class,
> all subclasses should implement "generate".
>
> I have an IncrementalGenerator subclass.
>
> So for now, I need to instantiate IncrementalGenerator,
> allowing for a future module to plugin their own generator.
>
> Any suggestions on how to do this?
> Thanks so much!!!!

You don't want an AccountNumberGenerator class and subclassing, all
you need is an iterator/generator of some form.

These might help:
http://docs.python.org/tutorial/classes.html#iterators
http://docs.python.org/tutorial/classes.html#generators
(in fact, that whole page is pretty relevant)

Once your code expects one of those, it's trivially easy to plug
something else in there.


From Scott.Daniels at Acm.Org  Tue Jul 14 11:44:04 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 08:44:04 -0700
Subject: Proposal: Decimal literals in Python.
In-Reply-To: <n46ai3t0biv5390r4ijhq6ddn9va47f197@4ax.com>
References: <4721ab28$0$1238$e4fe514c@dreader28.news.xs4all.nl>
	<1193438763.190428.134710@q5g2000prf.googlegroups.com>
	<87tzodii6i.fsf@benfinney.id.au>
	<1193494184.618613.81090@50g2000hsm.googlegroups.com>
	<n46ai3t0biv5390r4ijhq6ddn9va47f197@4ax.com>
Message-ID: <WN-dnXhGXtWYO8HXnZ2dnUVZ_j-dnZ2d@pdx.net>

Tim Roberts wrote:
> My favorite notation for this comes from Ada, which allows arbitrary bases
> from 2 to 16, and allows for underscores within numeric literals:
> 
>   x23_bin : constant :=  2#0001_0111#;
>   x23_oct : constant :=  8#27#;
>   x23_dec : constant := 10#23#;
>   x23_hex : constant := 16#17#;
And mine is one w/o the base 10 bias:
     .f.123 == 0x123
     .7.123 == 0o123
     .1.1101 == 0b1101
That is, .<largest allowed digit>.<digits>
-- show the base by showing base-1 in the base.
I actually built this into "OZ," an interpretter.

--Scott David Daniels
Scott.Daniels at Acm.Org


From pavlovevidence at gmail.com  Tue Jul 14 11:53:33 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 08:53:33 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<pan.2009.07.14.09.14.52@REMOVE.THIS.cybersource.com.au>
Message-ID: <ba24b9b8-f95d-4217-8e43-0fed8f4034b5@s6g2000vbp.googlegroups.com>

On Jul 14, 2:14?am, Steven D'Aprano
<ste... at REMOVE.THIS.cybersource.com.au> wrote:
> On Tue, 14 Jul 2009 01:30:48 -0700, Carl Banks wrote:
> > Seriously, do you *ever* take more than 2 seconds to consider whether
> > you might be missing something obvious before following up with these
> > indignant knee-jerk responses?
>
> Obviously not.
>
> [...]
>
> > Or would you rather let all unexpected exceptions print to standard
> > error, which is often a black hole in non-interactive sitations?
>
> Fair point. Of course you're right.

I don't want to be mean or anything.  I agree with you on 95% of
issues probably, of course I only follow up to disagree....

Carl Banks


From contact at xavierho.com  Tue Jul 14 11:54:05 2009
From: contact at xavierho.com (Xavier Ho)
Date: Tue, 14 Jul 2009 23:54:05 +0800
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <20090714152012.GY31378@wasteland.homelinux.net>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
	<20090714152012.GY31378@wasteland.homelinux.net>
Message-ID: <2d56febf0907140854s52d20904y90c7ccb6a0262cb9@mail.gmail.com>

I see. Thanks!

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Tue, Jul 14, 2009 at 11:20 PM, Jochen Schulz <ml at well-adjusted.de> wrote:

> Xavier Ho:
> >
> > Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
> -- snip
> > print a.n.extend([6, 7, 8, 9])
>
> extend doesn't fail. It just returns None and extends the list in place.
>
> In [1]: l = [1, 2, 3]
>
> In [2]: l.extend([4, 5, 6])
>
> In [3]: l
> Out[3]: [1, 2, 3, 4, 5, 6]
>
>
> J.
> --
> When I get home from the supermarket I don't know what to do with all the
> plastic.
> [Agree]   [Disagree]
>                 <http://www.slowlydownward.com/NODATA/data_enter2.html>
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.9 (GNU/Linux)
>
> iEYEARECAAYFAkpcoiwACgkQ+AfZydWK2zmchgCfZjRCOGTa0OZ1Q045sCLZfpvD
> EIEAnjJ8/uNwPYFfCsGNbQIDd5+LnkbA
> =fCdV
> -----END PGP SIGNATURE-----
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/cc25e4ed/attachment.html>

From python at mrabarnett.plus.com  Tue Jul 14 11:55:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 16:55:18 +0100
Subject: Proposal: Decimal literals in Python.
In-Reply-To: <WN-dnXhGXtWYO8HXnZ2dnUVZ_j-dnZ2d@pdx.net>
References: <4721ab28$0$1238$e4fe514c@dreader28.news.xs4all.nl>	<1193438763.190428.134710@q5g2000prf.googlegroups.com>	<87tzodii6i.fsf@benfinney.id.au>	<1193494184.618613.81090@50g2000hsm.googlegroups.com>	<n46ai3t0biv5390r4ijhq6ddn9va47f197@4ax.com>
	<WN-dnXhGXtWYO8HXnZ2dnUVZ_j-dnZ2d@pdx.net>
Message-ID: <4A5CAA66.3080608@mrabarnett.plus.com>

Scott David Daniels wrote:
> Tim Roberts wrote:
>> My favorite notation for this comes from Ada, which allows arbitrary 
>> bases
>> from 2 to 16, and allows for underscores within numeric literals:
>>
>>   x23_bin : constant :=  2#0001_0111#;
>>   x23_oct : constant :=  8#27#;
>>   x23_dec : constant := 10#23#;
>>   x23_hex : constant := 16#17#;
> And mine is one w/o the base 10 bias:
>     .f.123 == 0x123
>     .7.123 == 0o123
>     .1.1101 == 0b1101
> That is, .<largest allowed digit>.<digits>
> -- show the base by showing base-1 in the base.
> I actually built this into "OZ," an interpretter.
> 
Smalltalk uses "r" (for "radix"). If we also permit underscores:

     x23_bin =  2r0001_0111
     x23_oct =  8r27
     x23_dec = 10r23
     x23_hex = 16r17


From doctoresam at gmail.com  Tue Jul 14 11:55:36 2009
From: doctoresam at gmail.com (Deep_Feelings)
Date: Tue, 14 Jul 2009 08:55:36 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
Message-ID: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>

So you have chosen programming language "x" so shall you tell us why
you did so , and  what negatives or positives it has ?


From aahz at pythoncraft.com  Tue Jul 14 11:58:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 08:58:30 -0700
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <h3bogf$oo0$1@panix3.panix.com>
	<h3f5dt$dld$3@lust.ihug.co.nz> <m24otg3hkk.fsf@cs.uu.nl>
Message-ID: <h3i9v6$c5t$1@panix3.panix.com>

In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>> Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> (LD) wrote:
>
>>LD> In message <h3bogf$oo0$1 at panix3.panix.com>, Aahz wrote:
>
>>Aahz> class AttrDict:
>>Aahz>     def __getitem__(self, key):
>>Aahz>         return getattr(self, key)
>
>>LD> OK, let's try it:
>
>>LD> >>> c = {}
>>LD> >>> c["x"] = 3
>>LD> >>> c.x = 4   
>>LD>     Traceback (most recent call last):
>>LD>       File "<stdin>", line 1, in <module>
>>LD>     AttributeError: 'dict' object has no attribute 'x'
>>LD> >>> class AttrDict:
>>LD>     ...     def __getitem__(self, key):
>>LD>     ...         return getattr(self, key)
>>LD>     ...
>>LD> >>> c.x = 4
>>LD>     Traceback (most recent call last):
>>LD>       File "<stdin>", line 1, in <module>
>>LD>     AttributeError: 'dict' object has no attribute 'x'
>
>>LD> Nope, still doesn't work...
>
>Of course you need c = AttrDict()

Absolutely -- Lawrence really needs to learn to do his own debugging.

>And to get c.x = 4 working you also need a __setitem__. 

Nope.  You do need __setitem__ so that this works:

c['x'] = 4

>And to get c["x"] working AtrrDict should subclass dict:

Definitely not.  There's a perfectly good dict inside a regular class
instance already.  The only reason to subclass from dict is so that you
get all the dict methods for free; however, the cost is that you get
ugly bugs because of e.g.

c['update'] = 'foo'

Overally, I think it's much better/safer to explicitly pull the dict
methods you want to use.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From jfrancis4970 at mailinator.com  Tue Jul 14 11:58:44 2009
From: jfrancis4970 at mailinator.com (jfrancis4970 at mailinator.com)
Date: Tue, 14 Jul 2009 08:58:44 -0700 (PDT)
Subject: how to determine if python is run interactively? (-i)
Message-ID: <17280e94-6c15-4225-9d28-3dff4e0b61a5@p15g2000vbl.googlegroups.com>

how do you determine, from within a python program, whether the python
interpreter was launched in interactive mode? in other words, if i
have a program called "test.py", i want to ensure that the program was
launched with this command line:

python -i test.py

(and not just with "python test.py"). the reason is that i'm doing
some very expensive and lengthy initialization in my test.py program
that will be useless unless the program exits to the python prompt
when it is done, where the user can run further python commands.

obviously i can't use sys.argv since that is only for parameters
passed to the test.py program, not for parameters passed to the python
interpreter itself. i haven't found a way to access these options...

any help would be greatly appreciated!


From pavlovevidence at gmail.com  Tue Jul 14 12:01:37 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 09:01:37 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<h3hrb9$9c$2@lust.ihug.co.nz>
Message-ID: <7d161f1f-2c09-42ca-9bbd-b99a777044ea@j21g2000vbn.googlegroups.com>

On Jul 14, 4:48?am, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> In message <93f6a517-63d8-4c80-
>
> bf19-4614b7099... at m7g2000prd.googlegroups.com>, Carl Banks wrote:
> > Or would you rather let all unexpected exceptions print to standard
> > error, which is often a black hole in non-interactive sitations?
>
> Since when?
>
> Cron, for example, collects standard error and mails it to you.

1. Cron is only one way to run programs non-interactively. (Would that
work with, say, Windows services?)
2. Many systems don't run MTAs these days
3. In my experience the pipeline from cron to mail delivery is error
prone, mainly due to the complexity of configuring MTAs
4. Even if all this works, you might just want to do your logging
directly in Python anyway


Carl Banks


From rylesny at gmail.com  Tue Jul 14 12:12:01 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 14 Jul 2009 09:12:01 -0700 (PDT)
Subject: how to set timeout while colling a soap method?
References: <mailman.3051.1247490480.8015.python-list@python.org>
Message-ID: <e26bf425-f06a-49c3-8ad2-e52e82f3b080@r34g2000vba.googlegroups.com>

On Jul 13, 9:07?am, dzizes <dzizes... at gmail.com> wrote:
> Hello!
>
> I wrote some some python code for executing a soap method:
>
> import SOAPpy
> from SOAPpy import WSDL
>
> _server = WSDL.Proxy(some wsdl)
> r=_server.generuj(some parameters...)
> print r.encode('cp1250')
>
> It works fine. However, the execution time of this soap method might be
> long. Therefore, I would like to set a timeout like 1 minute, after which I
> would post a timeoute message.
>
> Any ideas?
> Greats,
>
> --
> View this message in context:http://www.nabble.com/how-to-set-timeout-while-colling-a-soap-method-...
> Sent from the Python - python-list mailing list archive at Nabble.com.

I don't believe SOAPpy supports this directly. You can set the timeout
globally before you make your SOAP call:

import socket
socket.setdefaulttimeout(60)

http://docs.python.org/library/socket.html#socket.setdefaulttimeout


From python at mrabarnett.plus.com  Tue Jul 14 12:14:03 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 17:14:03 +0100
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <4A5CAECB.8080604@mrabarnett.plus.com>

Deep_Feelings wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and  what negatives or positives it has ?

I've heard of "C" and "D", but not "x", unless you mean XPL (X
Programming Language) or PLAN-X. :-)


From duncan.booth at invalid.invalid  Tue Jul 14 12:26:28 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 14 Jul 2009 16:26:28 GMT
Subject: how to determine if python is run interactively? (-i)
References: <17280e94-6c15-4225-9d28-3dff4e0b61a5@p15g2000vbl.googlegroups.com>
Message-ID: <Xns9C48B169DC8C2duncanbooth@127.0.0.1>

jfrancis4970 at mailinator.com wrote:

> how do you determine, from within a python program, whether the python
> interpreter was launched in interactive mode?

sys.flags.interactive or sys.flags.inspect



From duncan.booth at invalid.invalid  Tue Jul 14 13:10:17 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 14 Jul 2009 17:10:17 GMT
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<mailman.3088.1247577307.8015.python-list@python.org>
Message-ID: <Xns9C48B8D5619D0duncanbooth@127.0.0.1>

John Machin <sjmachin at lexicon.net> wrote:

> Try an iterative version of checking that () [] and {}
> are balanced and nested appropriately.

Here's how I might approach the more general case:

def balanced(s, parens=("()",)):
    '''
    Example:
    >>> balanced('aAAA(b[bb(c]c))')
    True
    >>> balanced('aAAA(b[bb(c]c))', parens=("()", "[]"))
    False
    '''
    s = re.sub("[^%s]+" % re.escape("".join(parens)), "", s)
    for i in range(len(s)/2):
        for p in parens:
            s = s.replace(p, "")
    return not s

For short strings this is obviously slower than your 'iterative' function, 
but the run time mostly depends on the number of pairs of parentheses 
rather than the total length of the string, so for example it starts 
winning on a string with 2 pairs of parentheses about 75 characters long.


From amrita at iisermohali.ac.in  Tue Jul 14 13:33:59 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Tue, 14 Jul 2009 23:03:59 +0530 (IST)
Subject: select lines in python
Message-ID: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>

Dear all,

Can anyone tell me that suppose i have a file having content like:

    _Atom_name
      _Atom_type
      _Chem_shift_value
      _Chem_shift_value_error
      _Chem_shift_ambiguity_code
     1     1   PHE       H     H      8.49     0.02     1
     2     1   PHE       HA    H      4.60     0.02     1
     3     1   PHE       CA    C     57.83      0.3     1
     4     2   LEU       H     H      8.23     0.02     1
     5     2   LEU       HA    H      4.25     0.02     1
     6     2   LEU       HB2   H      1.54     0.02     1
     7     3   ASP       H     H      8.10     0.02     1
     8     3   ASP       HA    H      4.52     0.02     1
     9     3   ASP       HB2   H      2.65     0.02     1
stop


now what i want that instead of copying all the lines it will just write
the information about PHE and ASP then how i acn do that using python
programming.Kindly tell me the command for that.

Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From degibb at gmail.com  Tue Jul 14 13:48:06 2009
From: degibb at gmail.com (David Gibb)
Date: Tue, 14 Jul 2009 13:48:06 -0400
Subject: select lines in python
In-Reply-To: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
References: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
Message-ID: <ef49cad40907141048v6b0ee769jf250cf8aede8f860@mail.gmail.com>

try something like:

for line in open("filename").readlines():
    if (re.search("PHE|ASP",line):
        print line

On Tue, Jul 14, 2009 at 1:33 PM, <amrita at iisermohali.ac.in> wrote:
> Dear all,
>
> Can anyone tell me that suppose i have a file having content like:
>
> ? ?_Atom_name
> ? ? ?_Atom_type
> ? ? ?_Chem_shift_value
> ? ? ?_Chem_shift_value_error
> ? ? ?_Chem_shift_ambiguity_code
> ? ? 1 ? ? 1 ? PHE ? ? ? H ? ? H ? ? ?8.49 ? ? 0.02 ? ? 1
> ? ? 2 ? ? 1 ? PHE ? ? ? HA ? ?H ? ? ?4.60 ? ? 0.02 ? ? 1
> ? ? 3 ? ? 1 ? PHE ? ? ? CA ? ?C ? ? 57.83 ? ? ?0.3 ? ? 1
> ? ? 4 ? ? 2 ? LEU ? ? ? H ? ? H ? ? ?8.23 ? ? 0.02 ? ? 1
> ? ? 5 ? ? 2 ? LEU ? ? ? HA ? ?H ? ? ?4.25 ? ? 0.02 ? ? 1
> ? ? 6 ? ? 2 ? LEU ? ? ? HB2 ? H ? ? ?1.54 ? ? 0.02 ? ? 1
> ? ? 7 ? ? 3 ? ASP ? ? ? H ? ? H ? ? ?8.10 ? ? 0.02 ? ? 1
> ? ? 8 ? ? 3 ? ASP ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
> ? ? 9 ? ? 3 ? ASP ? ? ? HB2 ? H ? ? ?2.65 ? ? 0.02 ? ? 1
> stop
>
>
> now what i want that instead of copying all the lines it will just write
> the information about PHE and ASP then how i acn do that using python
> programming.Kindly tell me the command for that.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From phonky at europe.com  Tue Jul 14 13:50:54 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 19:50:54 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <f83064a1-49bd-4133-980c-ab847a0b3bdf@n30g2000vba.googlegroups.com>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<f83064a1-49bd-4133-980c-ab847a0b3bdf@n30g2000vba.googlegroups.com>
Message-ID: <cc950$4a5cc57e$d9a2f023$7401@news.hispeed.ch>

Thanks for all replies.

I need to practice much more pythonese....
In fact I don't think to understand all
of your suggestions, so I'll need to
go through them and decide what approach I am going
to take.

Thanks a lot!


From mensanator at aol.com  Tue Jul 14 13:52:39 2009
From: mensanator at aol.com (Mensanator)
Date: Tue, 14 Jul 2009 10:52:39 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com>

On Jul 14, 10:55?am, Deep_Feelings <doctore... at gmail.com> wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and ?what negatives or positives it has ?

language must have

- unlimited precision integers
- easy to program
- IDE not required
- reasonable speed
- math library needs to include number theoretic functions
  like GCD, LCM, Modular Inverse, etc.
- not fucking retarded like F#

That leaves Python (along with gympy, the Python wrapper for
the GMP library, which could be used with C or C++ if it weren't
for the ease of use issue) as the obvious choice.

As for negatives, the GMP library doesn't factor.

As for positives, you can call a factoring program from Python
and capture the output (and have it correct the bug in the factoring
program without having to fix the factoring program).


From tonylay at gmail.com  Tue Jul 14 13:59:24 2009
From: tonylay at gmail.com (Tony Lay)
Date: Tue, 14 Jul 2009 10:59:24 -0700 (PDT)
Subject: ImportError: No module named _functools
Message-ID: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>

I'm sooo close to getting this meld program running....had to install
a lot of things in /usr/local to get to pygtk2 functional and I'm
trying to run the meld program and get...

RHEL4 server


Traceback (most recent call last):
  File "/usr/local/bin/meld", line 35, in <module>
    import gettext
  File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
    import locale, copy, os, re, struct, sys
  File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
    import functools
  File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
    from _functools import partial, reduce
ImportError: No module named _functools

This is with me building all of the dependencies as well as python
with
./configure --prefix=/usr/local --exec-prefix=/usr/local
make distclean
make
make -i install
ldconfig

export PYTHONHOME=/usr/local/lib/python2.6
export PYTHONPATH=/usr/local/lib/python2.6:/usr/local/lib/python2.6/
site-packages

I thought it might have been an err of the application, but I ran
python and received the same error:
[root at orlstscts1 meld-1.0.0]# python
Python 2.6.2 (r262:71600, Jul 14 2009, 11:47:04)
[GCC 3.4.6 20060404 (Red Hat 3.4.6-9)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import functools
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
    from _functools import partial, reduce
ImportError: No module named _functools

Kind of a python n00b, but the functools.py is there, it's in the
path...everything seems to be lined up right.

Problem is that the server this is on is stable (read older), and I am
to not touch the older software unless it's as a last resort.  For
this reason everything is in /usr/local and built from the ground up.

I'm hoping that there's some silly dependency I'm missing.  I've
installed the following:
atk-1.26.0
pkg-config-0.23
cairo-1.8.8
libglade-2.6.4
pycairo-1.8.6
fontconfig-2.7.0
libpng-1.2.37
pygobject-2.18.0
freetype-2.1.10
libxml2-2.7.3
pygtk-2.15.2
gettext-0.17
meld-1.0.0
pygtk-2.8.6
glade3-3.6.7
meld-1.1.5
Python-2.6.2
glib-2.20.4
glibc-2.9
meld-1.3.0 (no install)
tcl8.5.7
tk8.5.7
gtk+-2.16.4
pango-1.20.5
intltool-0.35.5
pixman-0.15.14

Took me a while to get by fontconfig/freetype junk because (usr/local/
lib/libfontconfig.so: undefined reference to `FT_Select_Size') but
that's a little OT.

If there are any recommendations of what to attack or further
information would help let me know!

Regards,

-Tony


From weafon at lbl.gov  Tue Jul 14 14:03:22 2009
From: weafon at lbl.gov (weafon)
Date: Tue, 14 Jul 2009 11:03:22 -0700
Subject: How to keep a function as a generator function when the yield operator
	is moved into its sub-functions??
Message-ID: <4A5CC86A.9070907@lbl.gov>

Hi guys,

I have a question about the usage of yield. As shown in the below 
example, in general, if there is a code segment commonly used by two or 
more functions, we may isolate the segment into a function and then call 
it from other functions if necessary.

def func1():
    ....
    while(cond):
        .....
        commoncode()
        ...


def func2():
    ....
    while(cond):
        .....
        commoncode()
        ...

def commoncode()
    AAAA
    BBBB
    CCCC

However, if there is a 'yield' operation in the common code segment, the 
isolation causes that func1 and func2 become a non-generator function!! 
Although I can prevent such an isolation by just duplicating the segment 
in func1 and func2 to keep both of them being generator functions, the 
code may become ugly and hard to maintain particularly when coomoncode() 
is long.

The problem may be resolved if I can define the commoncode() as an 
inline function or marco. Unfortunately, inline and marco do not seems 
to be implemented in python. Thus, how can I isolate a common segment 
into a function when there are yield operations in the common segment?

Thanks,
Weafon







From nagle at animats.com  Tue Jul 14 14:06:17 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 14 Jul 2009 11:06:17 -0700
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <4a5cc8c0$0$1655$742ec2ed@news.sonic.net>

walterbyrd wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.
> 
> Since backward compatibility is being thrown away anyway, why not
> enforce the four space rule?
> 
> At least that way, when I get python code from somebody else, I would
> know what I am looking at, without having to do a hex dump, or
> something.

    Python 3 enforces the rule that you can't mix tabs and spaces
for indentation in the same file.  That (finally) guarantees that
the indentation you see is what the Python parser sees.  That's
enough to prevent non-visible indentation errors.

    It also means that the Python parser no longer has to have
any concept of how many spaces equal a tab.  So the problem
is now essentially solved.

					John Nagle


From rhodri at wildebst.demon.co.uk  Tue Jul 14 14:21:47 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 14 Jul 2009 19:21:47 +0100
Subject: select lines in python
In-Reply-To: <ef49cad40907141048v6b0ee769jf250cf8aede8f860@mail.gmail.com>
References: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
	<ef49cad40907141048v6b0ee769jf250cf8aede8f860@mail.gmail.com>
Message-ID: <op.uw2lalj8a8ncjz@gnudebst>

On Tue, 14 Jul 2009 18:48:06 +0100, David Gibb <degibb at gmail.com> wrote:

[Something top-posted, which I've shuffled down]

> On Tue, Jul 14, 2009 at 1:33 PM, <amrita at iisermohali.ac.in> wrote:
>> Dear all,
>>
>> Can anyone tell me that suppose i have a file having content like:
>>
>> ? ?_Atom_name
>> ? ? ?_Atom_type
>> ? ? ?_Chem_shift_value
>> ? ? ?_Chem_shift_value_error
>> ? ? ?_Chem_shift_ambiguity_code
>> ? ? 1 ? ? 1 ? PHE ? ? ? H ? ? H ? ? ?8.49 ? ? 0.02 ? ? 1
>> ? ? 2 ? ? 1 ? PHE ? ? ? HA ? ?H ? ? ?4.60 ? ? 0.02 ? ? 1
>> ? ? 3 ? ? 1 ? PHE ? ? ? CA ? ?C ? ? 57.83 ? ? ?0.3 ? ? 1
>> ? ? 4 ? ? 2 ? LEU ? ? ? H ? ? H ? ? ?8.23 ? ? 0.02 ? ? 1
>> ? ? 5 ? ? 2 ? LEU ? ? ? HA ? ?H ? ? ?4.25 ? ? 0.02 ? ? 1
>> ? ? 6 ? ? 2 ? LEU ? ? ? HB2 ? H ? ? ?1.54 ? ? 0.02 ? ? 1
>> ? ? 7 ? ? 3 ? ASP ? ? ? H ? ? H ? ? ?8.10 ? ? 0.02 ? ? 1
>> ? ? 8 ? ? 3 ? ASP ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
>> ? ? 9 ? ? 3 ? ASP ? ? ? HB2 ? H ? ? ?2.65 ? ? 0.02 ? ? 1
>> stop
>>
>>
>> now what i want that instead of copying all the lines it will just write
>> the information about PHE and ASP then how i acn do that using python
>> programming.Kindly tell me the command for that.

> try something like:
>
> for line in open("filename").readlines():
>     if (re.search("PHE|ASP",line):
>         print line
>

The readlines() is unnecessary, and if your file is at all long you'd
be better off precompiling the regular expression.

import re

expr = re.compile("PHE|ASP")
with open("filename") as f:
     for line in f:
         if expr.search(line):
             print line

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From milesck at umich.edu  Tue Jul 14 14:24:06 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Tue, 14 Jul 2009 14:24:06 -0400
Subject: How to keep a function as a generator function when the yield
	operator is moved into its sub-functions??
In-Reply-To: <4A5CC86A.9070907@lbl.gov>
References: <4A5CC86A.9070907@lbl.gov>
Message-ID: <388B397B-40B2-4A4E-857E-49C842708F7F@umich.edu>

On Jul 14, 2009, at 2:03 PM, weafon wrote:

> Hi guys,
>
> I have a question about the usage of yield. As shown in the below  
> example, in general, if there is a code segment commonly used by two  
> or more functions, we may isolate the segment into a function and  
> then call it from other functions if necessary.
>
> def func1():
>   ....
>   while(cond):
>       .....
>       commoncode()
>       ...
>
>
> def func2():
>   ....
>   while(cond):
>       .....
>       commoncode()
>       ...
>
> def commoncode()
>   AAAA
>   BBBB
>   CCCC
>
> However, if there is a 'yield' operation in the common code segment,  
> the isolation causes that func1 and func2 become a non-generator  
> function!! Although I can prevent such an isolation by just  
> duplicating the segment in func1 and func2 to keep both of them  
> being generator functions, the code may become ugly and hard to  
> maintain particularly when coomoncode() is long.
>
> The problem may be resolved if I can define the commoncode() as an  
> inline function or marco. Unfortunately, inline and marco do not  
> seems to be implemented in python. Thus, how can I isolate a common  
> segment into a function when there are yield operations in the  
> common segment?

def func1():
     ...
     while cond:
         ...
         for x in commoncode():
             yield x
         ...

See also:
  - PEP 380: http://www.python.org/dev/peps/pep-0380/
  - Stackless: http://www.stackless.com/

-Miles



From pfeldman at verizon.net  Tue Jul 14 14:25:08 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Tue, 14 Jul 2009 11:25:08 -0700 (PDT)
Subject: missing 'xor' Boolean operator
Message-ID: <24485116.post@talk.nabble.com>


Current Boolean operators are 'and', 'or', and 'not'.  It would be nice to
have an 'xor' operator as well.
-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24485116.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From stefan_ml at behnel.de  Tue Jul 14 14:26:30 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 14 Jul 2009 20:26:30 +0200
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>

Deep_Feelings wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and  what negatives or positives it has ?

Java, pays a living.

*duck*

Stefan


From http  Tue Jul 14 14:47:08 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 11:47:08 -0700
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com>
Message-ID: <7xab37t843.fsf@ruckus.brouhaha.com>

Mensanator <mensanator at aol.com> writes:
> - unlimited precision integers
> - easy to program
> - IDE not required
> - reasonable speed
> - math library needs to include number theoretic functions
>   like GCD, LCM, Modular Inverse, etc.
> - not fucking retarded like F#

Have you looked at Haskell?

> As for negatives, the GMP library doesn't factor.

Maybe with some MIRACL bindings...


From dickinsm at gmail.com  Tue Jul 14 14:47:41 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 14 Jul 2009 11:47:41 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
Message-ID: <057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>

On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
> have an 'xor' operator as well.

Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
that it's sufficiently useful to justify adding a new keyword 'xor' to
the language;  I suspect that would be an uphill struggle. :)

I'll just note that:

(1) It's easy to emulate xor:  'x xor y' <-> bool(x) != bool(y)

(2) 'and' and 'or' are special in that they have useful short-
circuiting behaviour; xor doesn't have this property (that is, you
always need to evaluate *both* operands to determine the result).

I'd also guess that 'xor' would be much less used than 'and' or 'or',
but maybe that's just a reflection of the sort of code that I tend to
write.

--
Mark


From amrita at iisermohali.ac.in  Tue Jul 14 15:10:32 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Wed, 15 Jul 2009 00:40:32 +0530 (IST)
Subject: select lines in python
Message-ID: <29449.210.212.36.65.1247598632.squirrel@www.iisermohali.ac.in>

Can i become more precise like instead of printing all lines for PHE and
ASP is it possible that for PHE python will print only those lines which
will have information about H and HA and for ASP it will print those lines
which will have information about HA and HB.

Thanks


> On Tue, 14 Jul 2009 18:48:06 +0100, David Gibb <degibb at gmail.com> wrote:
>
> [Something top-posted, which I've shuffled down]
>
>> On Tue, Jul 14, 2009 at 1:33 PM, <amrita at iisermohali.ac.in> wrote:
>>> Dear all,
>>>
>>> Can anyone tell me that suppose i have a file having content like:
>>>
>>> ?? ??_Atom_name
>>> ?? ?? ??_Atom_type
>>> ?? ?? ??_Chem_shift_value
>>> ?? ?? ??_Chem_shift_value_error
>>> ?? ?? ??_Chem_shift_ambiguity_code
>>> ?? ?? 1 ?? ?? 1 ?? PHE ?? ?? ?? H ?? ?? H ?? ?? ??8.49 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 2 ?? ?? 1 ?? PHE ?? ?? ?? HA ?? ??H ?? ?? ??4.60 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 3 ?? ?? 1 ?? PHE ?? ?? ?? CA ?? ??C ?? ?? 57.83 ?? ?? ??0.3 ?? ??
>>> 1
>>> ?? ?? 4 ?? ?? 2 ?? LEU ?? ?? ?? H ?? ?? H ?? ?? ??8.23 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 5 ?? ?? 2 ?? LEU ?? ?? ?? HA ?? ??H ?? ?? ??4.25 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 6 ?? ?? 2 ?? LEU ?? ?? ?? HB2 ?? H ?? ?? ??1.54 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 7 ?? ?? 3 ?? ASP ?? ?? ?? H ?? ?? H ?? ?? ??8.10 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 8 ?? ?? 3 ?? ASP ?? ?? ?? HA ?? ??H ?? ?? ??4.52 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 9 ?? ?? 3 ?? ASP ?? ?? ?? HB2 ?? H ?? ?? ??2.65 ?? ?? 0.02 ?? ??
>>> 1
>>> stop
>>>
>>>
>>> now what i want that instead of copying all the lines it will just
>>> write
>>> the information about PHE and ASP then how i acn do that using python
>>> programming.Kindly tell me the command for that.
>
>> try something like:
>>
>> for line in open("filename").readlines():
>>     if (re.search("PHE|ASP",line):
>>         print line
>>
>
> The readlines() is unnecessary, and if your file is at all long you'd
> be better off precompiling the regular expression.
>
> import re
>
> expr = re.compile("PHE|ASP")
> with open("filename") as f:
>      for line in f:
>          if expr.search(line):
>              print line
>
> --
> Rhodri James *-* Wildebeest Herder to the Masses
> --
> http://mail.python.org/mailman/listinfo/python-list
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From invalid at invalid  Tue Jul 14 15:12:53 2009
From: invalid at invalid (Grant Edwards)
Date: Tue, 14 Jul 2009 14:12:53 -0500
Subject: select lines in python
References: <mailman.3106.1247598636.8015.python-list@python.org>
Message-ID: <V9OdnccUnuAoRcHXnZ2dnUVZ_qednZ2d@posted.visi>

On 2009-07-14, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:

> Can i become more precise like instead of printing all lines
> for PHE and ASP is it possible that for PHE python will print
> only those lines which will have information about H and HA
> and for ASP it will print those lines which will have
> information about HA and HB?

Yes.

-- 
Grant Edwards                   grante             Yow! I KAISER ROLL?!
                                  at               What good is a Kaiser Roll
                               visi.com            without a little COLE SLAW
                                                   on the SIDE?


From knny.myer at gmail.com  Tue Jul 14 15:15:57 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 12:15:57 -0700 (PDT)
Subject: http://tinypic.com/view.php?pic=m78cgp&s=3
Message-ID: <ddf09334-ab38-4ec1-8186-b8a169f76cbf@q11g2000yqi.googlegroups.com>

Hi,

I'm experiencing a strange behaviour of the Python prompt when using
the
four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
getting
the previous and next command respectively I get ugly characters. See
it
yourself:
http://tinypic.com/view.php?pic=m78cgp&s=3

This is not directly Python-specific, but you feel quite handicapped
if
you must rewrite each command again... so my obvious question is:

How can I fix this? Please, let me know if you can tell me something.

Additional information:
I'm running Ubuntu Linux
I've tried the python prompt in several shell environments and got the
same issue in csh, dash... all negative.

Cheers,
Kenny


From knny.myer at gmail.com  Tue Jul 14 15:20:11 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 12:20:11 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
Message-ID: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>

Hi,

I'm experiencing a strange behaviour of the Python prompt when using
the
four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
getting
the previous and next command respectively I get ugly characters. See
it
yourself:
http://tinypic.com/view.php?pic=m78cgp&s=3

This is not directly Python-specific, but you feel quite handicapped
if
you must rewrite each command again... so my obvious question is:

How can I fix this? Please, let me know if you can tell me something.

Additional information:
I'm running Ubuntu Linux
I've tried the python prompt in several shell environments and got the
same issue in csh, dash... all negative.

Cheers,
Kenny


From dickinsm at gmail.com  Tue Jul 14 15:26:19 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 14 Jul 2009 12:26:19 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
References: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>
Message-ID: <722961de-8416-4aff-a1e2-ce0e18c65503@k1g2000yqf.googlegroups.com>

On Jul 14, 8:20?pm, "~km" <knny.m... at gmail.com> wrote:
> I'm experiencing a strange behaviour of the Python prompt when using
> the
> four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
> getting
> the previous and next command respectively I get ugly characters. See
> it
> yourself:http://tinypic.com/view.php?pic=m78cgp&s=3
>
> This is not directly Python-specific, but you feel quite handicapped
> if
> you must rewrite each command again... so my obvious question is:
>
> How can I fix this? Please, let me know if you can tell me something.
>
> Additional information:
> I'm running Ubuntu Linux
> I've tried the python prompt in several shell environments and got the
> same issue in csh, dash... all negative.

Where did your version of Python 2.6 come from?

If you built your copy of Python 2.6 from source, then the problem is
probably that either the readline library is missing, or (much more
likely) the include files for the readline library are missing.  Look
for a package called something like libreadline5-dev or readline-devel
and install it, and then try rebuilding Python.

Mark


From degibb at gmail.com  Tue Jul 14 15:26:29 2009
From: degibb at gmail.com (David Gibb)
Date: Tue, 14 Jul 2009 15:26:29 -0400
Subject: select lines in python
In-Reply-To: <V9OdnccUnuAoRcHXnZ2dnUVZ_qednZ2d@posted.visi>
References: <mailman.3106.1247598636.8015.python-list@python.org>
	<V9OdnccUnuAoRcHXnZ2dnUVZ_qednZ2d@posted.visi>
Message-ID: <ef49cad40907141226t7e15b091o616c26a9c0ddb5a2@mail.gmail.com>

I think what Grant is saying is that you should read the documentation
for the re module.

David

On Tue, Jul 14, 2009 at 3:12 PM, Grant Edwards<invalid at invalid> wrote:
> On 2009-07-14, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:
>
>> Can i become more precise like instead of printing all lines
>> for PHE and ASP is it possible that for PHE python will print
>> only those lines which will have information about H and HA
>> and for ASP it will print those lines which will have
>> information about HA and HB?
>
> Yes.
>
> --
> Grant Edwards ? ? ? ? ? ? ? ? ? grante ? ? ? ? ? ? Yow! I KAISER ROLL?!
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?at ? ? ? ? ? ? ? What good is a Kaiser Roll
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? visi.com ? ? ? ? ? ?without a little COLE SLAW
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? on the SIDE?
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From clp2 at rebertia.com  Tue Jul 14 15:43:42 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 12:43:42 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>

On Tue, Jul 14, 2009 at 11:47 AM, Mark Dickinson<dickinsm at gmail.com> wrote:
> On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
> wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
>> have an 'xor' operator as well.
>
> Hmm. ?I don't think 'nice' is sufficient. ?You'd need to make the case
> that it's sufficiently useful to justify adding a new keyword 'xor' to
> the language; ?I suspect that would be an uphill struggle. :)
>
> I'll just note that:
>
> (1) It's easy to emulate xor: ?'x xor y' <-> bool(x) != bool(y)

Using the xor bitwise operator is also an option:
bool(x) ^ bool(y)

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Tue Jul 14 15:50:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 12:50:13 -0700
Subject: http://tinypic.com/view.php?pic=m78cgp&s=3
In-Reply-To: <ddf09334-ab38-4ec1-8186-b8a169f76cbf@q11g2000yqi.googlegroups.com>
References: <ddf09334-ab38-4ec1-8186-b8a169f76cbf@q11g2000yqi.googlegroups.com>
Message-ID: <50697b2c0907141250k6f44fc8buda78c22a0a1989b@mail.gmail.com>

On Tue, Jul 14, 2009 at 12:15 PM, ~km<knny.myer at gmail.com> wrote:
> Hi,
>
> I'm experiencing a strange behaviour of the Python prompt when using
> the
> four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
> getting
> the previous and next command respectively I get ugly characters. See
> it
> yourself:
> http://tinypic.com/view.php?pic=m78cgp&s=3
>
> This is not directly Python-specific, but you feel quite handicapped
> if
> you must rewrite each command again... so my obvious question is:
>
> How can I fix this? Please, let me know if you can tell me something.

I would guess that your Python wasn't compiled with GNU readline support.
Do you get an error if you `import readline`?

Cheers,
Chris
-- 
http://blog.rebertia.com


From dickinsm at gmail.com  Tue Jul 14 15:52:34 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 14 Jul 2009 12:52:34 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<mailman.3108.1247600624.8015.python-list@python.org>
Message-ID: <e8e81467-2752-4176-8ad6-f0326a99ac14@i6g2000yqj.googlegroups.com>

On Jul 14, 8:43?pm, Chris Rebert <c... at rebertia.com> wrote:
> On Tue, Jul 14, 2009 at 11:47 AM, Mark Dickinson<dicki... at gmail.com> wrote:
> > (1) It's easy to emulate xor: ?'x xor y' <-> bool(x) != bool(y)
>
> Using the xor bitwise operator is also an option:
> bool(x) ^ bool(y)

Good point.  For some reason I expected bitwise operations on bools to
return ints rather than bools.  Now I know better. :-)

Thanks,

Mark


From pfeldman at verizon.net  Tue Jul 14 15:56:02 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Tue, 14 Jul 2009 12:56:02 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <24486661.post@talk.nabble.com>


!= does do what I want, except that it doesn't indicate to someone reading
the code that the operands are being treated as logicals.  (Readability is
supposed to be one of the major selling points of Python).  But, this is
probably good enough.

Here's a related issue: I would like to see an option for type checking on
operands of logical operators, so that attempting to apply a logical
operator to non-Boolean entities generates a warning message.  With operand
type checking, 'xor' and != would be different.


Mark Dickinson wrote:
> 
> On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
> wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice
>> to
>> have an 'xor' operator as well.
> 
> Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
> that it's sufficiently useful to justify adding a new keyword 'xor' to
> the language;  I suspect that would be an uphill struggle. :)
> 
> I'll just note that:
> 
> (1) It's easy to emulate xor:  'x xor y' <-> bool(x) != bool(y)
> 
> (2) 'and' and 'or' are special in that they have useful short-
> circuiting behaviour; xor doesn't have this property (that is, you
> always need to evaluate *both* operands to determine the result).
> 
> I'd also guess that 'xor' would be much less used than 'and' or 'or',
> but maybe that's just a reflection of the sort of code that I tend to
> write.
> 
> --
> Mark
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24486661.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From jgardner at jonathangardner.net  Tue Jul 14 16:05:48 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Tue, 14 Jul 2009 13:05:48 -0700 (PDT)
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
Message-ID: <df69e052-9979-4bf9-abd5-a9ef229681bf@b14g2000yqd.googlegroups.com>

On Jul 14, 7:03?am, phonky <pho... at europe.com> wrote:
>
> Now, I do not know yet how the account number scheme looks like.

Exactly. The data store knows a lot more than the client (your
program) will ever know.

The correct answer is to do nothing. Use your data store to generate
the IDs for you. The implementations discussed here will not generate
unique IDs across invocations, but the data store will persist the
sequence for you appropriately.

The more correct answer is to abstract away the client to your data
store as well. See SQLAlchemy.

If you're writing a data store, you're doing it wrong. See PostgreSQL,
MySQL, or any other data store out there that are perfectly fine for
development and production use.

I like to use UUIDs for the IDs. Others like big ints that are a
sequence. I've seen people use encrypted big ints, basically random
strings that aren't really random. In the end, you only have to change
the code that talks to the data store, and the rest of your program
only cares about the equality of the id.


From clp2 at rebertia.com  Tue Jul 14 16:22:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 13:22:20 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <24486661.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com>
Message-ID: <50697b2c0907141322y3ec27688g4e6bc29d8fc4b7bf@mail.gmail.com>

> Mark Dickinson wrote:
>>
>> On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
>> wrote:
>>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice
>>> to
>>> have an 'xor' operator as well.
>>
>> Hmm. ?I don't think 'nice' is sufficient. ?You'd need to make the case
>> that it's sufficiently useful to justify adding a new keyword 'xor' to
>> the language; ?I suspect that would be an uphill struggle. :)
>>
>> I'll just note that:
>>
>> (1) It's easy to emulate xor: ?'x xor y' <-> bool(x) != bool(y)
>>
>> (2) 'and' and 'or' are special in that they have useful short-
>> circuiting behaviour; xor doesn't have this property (that is, you
>> always need to evaluate *both* operands to determine the result).
>>
>> I'd also guess that 'xor' would be much less used than 'and' or 'or',
>> but maybe that's just a reflection of the sort of code that I tend to
>> write.
On Tue, Jul 14, 2009 at 12:56 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
<snip>
> Here's a related issue: I would like to see an option for type checking on
> operands of logical operators, so that attempting to apply a logical
> operator to non-Boolean entities generates a warning message.  With operand
> type checking, 'xor' and != would be different.

That's probably not gonna happen. Python is dynamically and duck
typed, and has a sweet coercion system (__bool__ or __nonzero__
depending on your version) to coerce non-booleans to booleans in a
sensible and useful way. So, it's not gonna change any time soon.

Some illustrative examples:
>>> #empty containers considered false
>>> bool([] or {} or set() or "")
>>> False
>>> #zero and null considered false
>>> bool(0 or None)
>>> False
>>> #anything else is, by default, true
>>> bool(object())
>>> True

And like I said, a class can override a special method to provide
whatever boolean semantics are desired. It's surprisingly handy.

Cheers,
Chris
-- 
http://blog.rebertia.com


From jgardner at jonathangardner.net  Tue Jul 14 16:24:29 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Tue, 14 Jul 2009 13:24:29 -0700 (PDT)
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org> 
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org> 
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com> 
	<hi3p551ikld7d00c3dvs1vhkmnjgg8ffcn@4ax.com>
Message-ID: <681fe49e-7063-47c5-b0c5-d5088ab216c1@g31g2000yqc.googlegroups.com>

On Jul 14, 6:56?am, Fred Atkinson <fatkin... at mishmash.com> wrote:
>
> Agreed, it doesn't. ?But if my hosting provider won't change it, I'm
> stuck with it. ?
>

Nowadays you can find hosts that allow you to run FastCGI scripts in
any language for dirt cheap. (Hostmonster for instance.) If your host
doesn't allow it, it's time to upgrade.

Any hosting service that supports Ruby on Rails supports Python
through the exact same mechanism.


From aahz at pythoncraft.com  Tue Jul 14 16:30:43 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 13:30:43 -0700
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
Message-ID: <h3iptj$ave$1@panix3.panix.com>

In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
Stefan Behnel  <stefan_ml at behnel.de> wrote:
>Deep_Feelings wrote:
>>
>> So you have chosen programming language "x" so shall you tell us why
>> you did so , and  what negatives or positives it has ?
>
>*duck*

Where do you get the duck programming language?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From jakub.piotr.nowak at gmail.com  Tue Jul 14 16:39:28 2009
From: jakub.piotr.nowak at gmail.com (Jakub P. Nowak)
Date: Tue, 14 Jul 2009 13:39:28 -0700 (PDT)
Subject: ANN: RuPy '09 Conference
Message-ID: <b80b3d32-01ee-4786-aa5b-d0815fd45450@n11g2000yqb.googlegroups.com>

RuPy 2009 :: Strongly Dynamic Conference

Poznan, Poland
November 7-8, 2009

:: Call for speakers

RuPy is a conference about dynamically typed programming languages.
Held for the first time in April 2007 it gathered enthusiasts
from Poland and other countries.

The idea behind the conference is to liven up the
community and make these technologies more popular in Europe.

The first conference was a middle-sized one but came out as
a huge success. We believe it was a great experience for both
attendees and speakers.

RuPy 2009 committee is looking for speakers willing to present
a Python, Ruby, Groovy or any other related subject.
If you have an interesting talk in mind go ahead and submit a
talk proposal. The talk proposal should include a talk title,
brief introduction and your short resume/biography.

To our invited speakers we offer free accommodation, full
board and possibility to interact with a very lively IT community.
You are also free to participate in all the extra events -
'Geek party' always turns out great!

You can also support us by linking to our site and informing
all your friends about the event and the possibility to submit
a talk proposal.

Potential speakers should submit an abstract using the following
form:

https://spreadsheets.google.com/viewform?formkey=dEFEYndsQWR2TGFzRFpzcU9IbFlCT2c6MA..

by September 30th, 2009 for consideration.

If you have any special presentation needs, let us know.

For more details check our site:
http://www.rupy.eu

Best regards,
--
Jakub P. Nowak
RuPy Committee


From suruti94 at gmail.com  Tue Jul 14 16:40:38 2009
From: suruti94 at gmail.com (Mohan Parthasarathy)
Date: Tue, 14 Jul 2009 13:40:38 -0700
Subject: Calling functions: Why this complicated ?
Message-ID: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>

Hi,
I am a newbie. I am reading

http://www.network-theory.co.uk/docs/pytut/KeywordArguments.html

Defining a function with "N" arguments and calling them in "M" different
ways. Why does it have to be this complicated ? I like the idea of calling
the function by explicitly naming the arguments, but there are so many other
ways here that is very confusing. Do people really use all these features ?
Perhaps, there is a equivalent book to "Javascript: Good Parts" for Python ?

-thanks
mohan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/6e6d6d13/attachment.html>

From piet at cs.uu.nl  Tue Jul 14 16:45:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 22:45:46 +0200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<h3hrb9$9c$2@lust.ihug.co.nz>
	<7d161f1f-2c09-42ca-9bbd-b99a777044ea@j21g2000vbn.googlegroups.com>
Message-ID: <m2bpnnyow5.fsf@cs.uu.nl>

>>>>> Carl Banks <pavlovevidence at gmail.com> (CB) wrote:

>CB> On Jul 14, 4:48?am, Lawrence D'Oliveiro <l... at geek-
>central.gen.new_zealand> wrote:
>>> In message <93f6a517-63d8-4c80-
>>> 
>>> bf19-4614b7099... at m7g2000prd.googlegroups.com>, Carl Banks wrote:
>>> > Or would you rather let all unexpected exceptions print to standard
>>> > error, which is often a black hole in non-interactive sitations?
>>> 
>>> Since when?
>>> 
>>> Cron, for example, collects standard error and mails it to you.

>CB> 1. Cron is only one way to run programs non-interactively. (Would that
>CB> work with, say, Windows services?)
>CB> 2. Many systems don't run MTAs these days
>CB> 3. In my experience the pipeline from cron to mail delivery is error
>CB> prone, mainly due to the complexity of configuring MTAs
>CB> 4. Even if all this works, you might just want to do your logging
>CB> directly in Python anyway

Even then, I think the program would get structured better if the FTP
code would only catch FTP-specific errors, including socket errors
(which is what all_errors does) and to catch programming errors etc on
another level, e.g by the mentioned sys.excepthook.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From deets at nospam.web.de  Tue Jul 14 16:59:04 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 14 Jul 2009 22:59:04 +0200
Subject: How to keep a function as a generator function when the yield
	operator   is moved into its sub-functions??
In-Reply-To: <mailman.3102.1247595252.8015.python-list@python.org>
References: <mailman.3102.1247595252.8015.python-list@python.org>
Message-ID: <7c49soF25pgh4U1@mid.uni-berlin.de>

weafon schrieb:
> Hi guys,
> 
> I have a question about the usage of yield. As shown in the below 
> example, in general, if there is a code segment commonly used by two or 
> more functions, we may isolate the segment into a function and then call 
> it from other functions if necessary.
> 
> def func1():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
> 
> 
> def func2():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
> 
> def commoncode()
>    AAAA
>    BBBB
>    CCCC
> 
> However, if there is a 'yield' operation in the common code segment, the 
> isolation causes that func1 and func2 become a non-generator function!! 


No. Not writing them as generators makes them a non-generator-function.

You are way to unspecific with your examples. But if func1 and func2 are 
themselves supposed to be generators, there is nothing preventing you 
from using them as such.

Diez


From robert.kern at gmail.com  Tue Jul 14 16:59:32 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Tue, 14 Jul 2009 15:59:32 -0500
Subject: missing 'xor' Boolean operator
In-Reply-To: <24486661.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com>
Message-ID: <h3irjm$ro$1@ger.gmane.org>

On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
> != does do what I want, except that it doesn't indicate to someone reading
> the code that the operands are being treated as logicals.  (Readability is
> supposed to be one of the major selling points of Python).  But, this is
> probably good enough.

In the words of those greater than myself, "Not every one-liner needs to be in 
the standard library."

def xor(a, b):
     return bool(a) != bool(b)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From piet at cs.uu.nl  Tue Jul 14 16:59:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 22:59:34 +0200
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <h3bogf$oo0$1@panix3.panix.com>
	<h3f5dt$dld$3@lust.ihug.co.nz> <m24otg3hkk.fsf@cs.uu.nl>
	<h3i9v6$c5t$1@panix3.panix.com>
Message-ID: <m27hybyo95.fsf@cs.uu.nl>

>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:

>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>A> <piet at cs.uu.nl> wrote: 

>>> And to get c.x = 4 working you also need a __setitem__. 

>A> Nope.  You do need __setitem__ so that this works:

>A> c['x'] = 4

Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
that was what the OP wanted (I think).
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From db3l.net at gmail.com  Tue Jul 14 17:06:03 2009
From: db3l.net at gmail.com (David Bolen)
Date: Tue, 14 Jul 2009 17:06:03 -0400
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
Message-ID: <m2prc3dlfo.fsf@valheru.db3l.homeip.net>

John Nagle <nagle at animats.com> writes:

>    Python 3 enforces the rule that you can't mix tabs and spaces
> for indentation in the same file.  That (finally) guarantees that
> the indentation you see is what the Python parser sees.  That's
> enough to prevent non-visible indentation errors.

Are you sure?  It seems to restrict them in the same block, but not in
the entire file.  At least I was able to use both space and tab
indented blocks in the same file with Python 3.0 and 3.1.  I suspect
precluding any mixture at all at the file level would be more
intrusive, for example, when trying to combine multiple code sources
in a single file.

Not that this really changes your final point, since the major risk
of a mismatch between the parser vs. visual display is within a single
block.

>    It also means that the Python parser no longer has to have
> any concept of how many spaces equal a tab.  So the problem
> is now essentially solved.

"has to have" being a future possibility at this point, since I'm
fairly sure the 3.x parser does technically still have the concept of
a tab size of 8, though now it can be an internal implementation
detail.

-- David


From ethan at stoneleaf.us  Tue Jul 14 17:38:12 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 14:38:12 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3irjm$ro$1@ger.gmane.org>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>
	<h3irjm$ro$1@ger.gmane.org>
Message-ID: <4A5CFAC4.7020300@stoneleaf.us>

Robert Kern wrote:
> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
> 
>> != does do what I want, except that it doesn't indicate to someone 
>> reading
>> the code that the operands are being treated as logicals.  
>> (Readability is
>> supposed to be one of the major selling points of Python).  But, this is
>> probably good enough.
> 
> 
> In the words of those greater than myself, "Not every one-liner needs to 
> be in the standard library."
> 
> def xor(a, b):
>     return bool(a) != bool(b)
> 

Let's see...

   and returns the last object that is "true"
   or  returns the first object that is "true"

so should xor return the only object that is "true", else False/None?

def xor(a, b)
     if a and b:
         return None
     elif a:
         return a
     elif b:
         return b
     else:
         return None

~Ethan~


From nobody at nowhere.com  Tue Jul 14 17:40:27 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 14 Jul 2009 22:40:27 +0100
Subject: How to check if any item from a list of strings is in a
	big	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>
	<mailman.3073.1247547957.8015.python-list@python.org>
Message-ID: <pan.2009.07.14.21.40.27.578000@nowhere.com>

On Tue, 14 Jul 2009 02:06:04 -0300, Gabriel Genellina wrote:

>> Matt, how many words are you looking for, in how long a string ?
>> Were you able to time any( substr in long_string ) against re.compile
>> ( "|".join( list_items )) ?
> 
> There is a known algorithm to solve specifically this problem  
> (Aho-Corasick), a good implementation should perform better than R.E. (and  
> better than the gen.expr. with the advantage of returning WHICH string  
> matched)

Aho-Corasick has the advantage of being linear in the length of the
patterns, so the setup may be faster than re.compile(). The actual
searching won't necessarily be any faster (assuming optimal
implementations; I don't know how safe that assumption is).



From ken at seehart.com  Tue Jul 14 17:44:51 2009
From: ken at seehart.com (Ken Seehart)
Date: Tue, 14 Jul 2009 14:44:51 -0700
Subject: decorators - would be nice if...
Message-ID: <4A5CFC53.7050902@seehart.com>

Almost every time I use decorators, I find myself wishing I had access
to the local namespace of the context from which the decorator is
executed.  In practice, decorator is being applied to a method, so the
namespace in question would be the dictionary of the class being created.

Similarly, before decorators were around, I often found myself lamenting
the fact that a class is not created until after it's scope is
completed, since this makes certain kinds of metaprogramming more
difficult.  But after digging deeper, I realized why it is the way it
is, so I don't complain about that.

But it would have been a simple thing to add an argument 'locals' to the
decorator specification.  It's somewhat more difficult to add that now
because of compatibility issues, but perhaps there is a way to get the
same effect.

I can work around all of this by making my decorators just store data to
be processed by a metaclass, but that solution is less elegant.  Also,
it has the slight disadvantage of requiring the use of a metaclass which
would otherwise not be necessary.  I prefer to save metaclass
implementation as a last resort for various reasons (e.g. there does not
seem to be a good way to use multiple metaclasses in a class hierarchy,
and more generally you can't stack them on top of each other (you can
only have one metaclass per class)).

Thoughts?

- Ken




From knny.myer at gmail.com  Tue Jul 14 17:47:04 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 14:47:04 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
References: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>
	<722961de-8416-4aff-a1e2-ce0e18c65503@k1g2000yqf.googlegroups.com>
Message-ID: <21a14a9e-2837-4ae1-a55b-c6b3d50c0513@k19g2000yqn.googlegroups.com>

On 14 Jul., 15:26, Mark Dickinson <dicki... at gmail.com> wrote:
> Where did your version of Python 2.6 come from?
>
> If you built your copy of Python 2.6 from source, then the problem is
> probably that either the readline library is missing, or (much more
> likely) the include files for the readline library are missing. ?Look
> for a package called something like libreadline5-dev or readline-devel
> and install it, and then try rebuilding Python.
>
> Mark

Yes, I built it from source and never thought that there might be such
a library. Now I've re-compiled and my problem is solved!

Have many thanks Mark, and Chris Rebert, too, who responded to my
deleted post, which I've received per mail. Sorry for that incidence.

Cheers,
Kenny


From knny.myer at gmail.com  Tue Jul 14 17:47:17 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 14:47:17 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
References: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>
	<722961de-8416-4aff-a1e2-ce0e18c65503@k1g2000yqf.googlegroups.com>
Message-ID: <c99583e2-c02d-4cbb-9b81-8de6b77abc61@h18g2000yqj.googlegroups.com>

On 14 Jul., 15:26, Mark Dickinson <dicki... at gmail.com> wrote:
> Where did your version of Python 2.6 come from?
>
> If you built your copy of Python 2.6 from source, then the problem is
> probably that either the readline library is missing, or (much more
> likely) the include files for the readline library are missing. ?Look
> for a package called something like libreadline5-dev or readline-devel
> and install it, and then try rebuilding Python.
>
> Mark

Yes, I built it from source and never thought that there might be such
a library. Now I've re-compiled and my problem is solved!

Have many thanks Mark, and Chris Rebert, too, who responded to my
deleted post, which I've received per mail. Sorry for that incidence.

Cheers,
Kenny


From python at mrabarnett.plus.com  Tue Jul 14 17:58:27 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 22:58:27 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5CFAC4.7020300@stoneleaf.us>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
Message-ID: <4A5CFF83.9070301@mrabarnett.plus.com>

Ethan Furman wrote:
> Robert Kern wrote:
>> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
>>
>>> != does do what I want, except that it doesn't indicate to someone 
>>> reading
>>> the code that the operands are being treated as logicals.  
>>> (Readability is
>>> supposed to be one of the major selling points of Python).  But, this is
>>> probably good enough.
>>
>>
>> In the words of those greater than myself, "Not every one-liner needs 
>> to be in the standard library."
>>
>> def xor(a, b):
>>     return bool(a) != bool(b)
>>
> 
> Let's see...
> 
>   and returns the last object that is "true"
>   or  returns the first object that is "true"
> 
> so should xor return the only object that is "true", else False/None?
> 
> def xor(a, b)
>     if a and b:
>         return None
>     elif a:
>         return a
>     elif b:
>         return b
>     else:
>         return None
> 
How about:

def xor(a, b):
     return not b and a or not a and b


From nobody at nowhere.com  Tue Jul 14 17:58:28 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 14 Jul 2009 22:58:28 +0100
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com>
	<7xab37t843.fsf@ruckus.brouhaha.com>
Message-ID: <pan.2009.07.14.21.58.28.860000@nowhere.com>

On Tue, 14 Jul 2009 11:47:08 -0700, Paul Rubin wrote:

>> - unlimited precision integers
>> - easy to program
>> - IDE not required
>> - reasonable speed
>> - math library needs to include number theoretic functions
>>   like GCD, LCM, Modular Inverse, etc.
>> - not fucking retarded like F#
> 
> Have you looked at Haskell?

Given his comment about F#, I have a suspicion that he might be
dogmatically opposed to functional languages generally.



From deets at nospam.web.de  Tue Jul 14 18:03:03 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 00:03:03 +0200
Subject: decorators - would be nice if...
In-Reply-To: <mailman.3115.1247607911.8015.python-list@python.org>
References: <mailman.3115.1247607911.8015.python-list@python.org>
Message-ID: <7c4dknF253b3tU1@mid.uni-berlin.de>

Ken Seehart schrieb:
> Almost every time I use decorators, I find myself wishing I had access
> to the local namespace of the context from which the decorator is
> executed.  In practice, decorator is being applied to a method, so the
> namespace in question would be the dictionary of the class being created.

You can access the instance.

def decorator(method):
     def _d(self, *args, **kwargs):
         print self.__dict__
         return method(self, *args, **kwargs)

     return _d

class Foo(object):

     @decorator
     def bar(self, a, b):
         print "bar"


f = Foo()

f.bar(1, 2)

So what exactly it is you are missing? The method's locals()?

And could you explain *why* you are missing this?


Diez


From ethan at stoneleaf.us  Tue Jul 14 18:11:40 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 15:11:40 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5CFF83.9070301@mrabarnett.plus.com>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
Message-ID: <4A5D029C.5030700@stoneleaf.us>

MRAB wrote:
> Ethan Furman wrote:
> 
>> Robert Kern wrote:
>>
>>> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
>>>
>>>> != does do what I want, except that it doesn't indicate to someone 
>>>> reading
>>>> the code that the operands are being treated as logicals.  
>>>> (Readability is
>>>> supposed to be one of the major selling points of Python).  But, 
>>>> this is
>>>> probably good enough.
>>>
>>>
>>>
>>> In the words of those greater than myself, "Not every one-liner needs 
>>> to be in the standard library."
>>>
>>> def xor(a, b):
>>>     return bool(a) != bool(b)
>>>
>>
>> Let's see...
>>
>>   and returns the last object that is "true"
>>   or  returns the first object that is "true"
>>
>> so should xor return the only object that is "true", else False/None?
>>
>> def xor(a, b)
>>     if a and b:
>>         return None
>>     elif a:
>>         return a
>>     elif b:
>>         return b
>>     else:
>>         return None
>>
> How about:
> 
> def xor(a, b):
>     return not b and a or not a and b

In [12]: not 1 and 0 or 1 and not 0
Out[12]: True

In [13]: not 0 and 0 or 0 and not 0
Out[13]: 0

In [14]: not 1 and 1 or 1 and not 1
Out[14]: False

In [15]: not [] and [] or [] and not []
Out[15]: []

Doesn't produce consistent objects, sometimes bool, sometimes something 
else.  'Course, it all depends on what you need.

~Ethan~


From pavlovevidence at gmail.com  Tue Jul 14 18:26:06 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 15:26:06 -0700 (PDT)
Subject: decorators - would be nice if...
References: <mailman.3115.1247607911.8015.python-list@python.org>
Message-ID: <ee0e1bbd-d411-40fa-ae0a-44fef9ea86fe@g31g2000yqc.googlegroups.com>

On Jul 14, 2:44?pm, Ken Seehart <k... at seehart.com> wrote:
[snip]
(e.g. there does not
> seem to be a good way to use multiple metaclasses in a class hierarchy,
> and more generally you can't stack them on top of each other (you can
> only have one metaclass per class)).
>
> Thoughts?

If "stacking" metaclasses (whatever that means) is a possible approach
to your problem, you might want to ask yourself if you're trying to be
too clever.

Would you like to give us an example of a decorator you think would
benefit from having access to local namespace?  We might be able to
suggest other possibilities.


Carl Banks


From darkwater42 at gmail.com  Tue Jul 14 18:54:31 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 15:54:31 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<4a5c5e7f$0$30235$9b4e6d93@newsspool1.arcor-online.net>
Message-ID: <d0afeb7e-1120-4fff-b9cc-42ff8a0ced77@h11g2000yqb.googlegroups.com>

On Jul 14, 7:38?am, Florian Brucker <t... at torfbold.com> wrote:

> Douglas Alan wrote:

> > Thank you. My question wasn't intended to be Python specific, though.
> > I am just curious for purely academic reasons about whether there is
> > such an algorithm. All the sources I've skimmed only seem to the
> > answer the question via omission. Which is kind of strange, since it
> > seems to me like an obvious question to ask.

> IIRC comp.programming would be the place to ask such questions.

Thanks, yes that does look like a good place to post such questions.
Unfortunately, it also looks to be overrun with stories on "hot girls
top and bottom sexy movie", though I'm sure I can ignore those. I'm
scared to look at the posting on "tricky bit twiddling", though.

|>ouglas



From aahz at pythoncraft.com  Tue Jul 14 18:58:06 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 15:58:06 -0700
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <m24otg3hkk.fsf@cs.uu.nl>
	<h3i9v6$c5t$1@panix3.panix.com> <m27hybyo95.fsf@cs.uu.nl>
Message-ID: <h3j2hu$nmf$1@panix3.panix.com>

In article <m27hybyo95.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>
>>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>>A> <piet at cs.uu.nl> wrote: 
>
>>>> And to get c.x = 4 working you also need a __setitem__. 
>
>>A> Nope.  You do need __setitem__ so that this works:
>
>>A> c['x'] = 4
>
>Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
>that was what the OP wanted (I think).

c.x = 4 
already updates the instance dict, so there's no need to change any class
methods to support it.  That is, IME it's much better to add methods to
a regular class to make it more dict-like using the built-in instance
dict rather than changing any of the attribute mechanisms.  If you're
really curious, I recommend trying several approaches yourself to see
what works better.  ;-)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From Scott.Daniels at Acm.Org  Tue Jul 14 19:00:03 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 16:00:03 -0700
Subject: How to check if any item from a list of strings is in a big
	string?
In-Reply-To: <pan.2009.07.14.21.40.27.578000@nowhere.com>
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>
	<mailman.3073.1247547957.8015.python-list@python.org>
	<pan.2009.07.14.21.40.27.578000@nowhere.com>
Message-ID: <3cCdna9IneyskcDXnZ2dnUVZ_g6dnZ2d@pdx.net>

Nobody wrote:
> On Tue, 14 Jul 2009 02:06:04 -0300, Gabriel Genellina wrote:
> 
>>> Matt, how many words are you looking for, in how long a string ?
>>> Were you able to time any( substr in long_string ) against re.compile
>>> ( "|".join( list_items )) ?
>> There is a known algorithm to solve specifically this problem  
>> (Aho-Corasick), a good implementation should perform better than R.E. (and  
>> better than the gen.expr. with the advantage of returning WHICH string  
>> matched)
> 
> Aho-Corasick has the advantage of being linear in the length of the
> patterns, so the setup may be faster than re.compile(). The actual
> searching won't necessarily be any faster (assuming optimal
> implementations; I don't know how safe that assumption is).
> 
Having done a fast Aho-Corasick implementation myself, I can assure you
that the actual searching can be incredibly fast.  RE conversion usually
goes to a slightly more general machine than the Aho-Corasick processing
requires.

--Scott David Daniels
Scott.Daniels at Acm.Org



From dstanek at dstanek.com  Tue Jul 14 19:03:02 2009
From: dstanek at dstanek.com (David Stanek)
Date: Tue, 14 Jul 2009 19:03:02 -0400
Subject: How to unbuffer Python's output
In-Reply-To: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
References: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
Message-ID: <de32cc030907141603u6767b6edi7290d42fbd37a644@mail.gmail.com>

2009/7/14 Lily Gao <Lily.Gao at autodesk.com>:
> Hi, All
>
> I am calling a python program in perl and use redirection,
>
> Like :
>
> `python x.py > 1.log 2>&1`

Try tihs instead:
    python x.py 2>&1 > 1.log

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From freyr.magnusson at gmail.com  Tue Jul 14 19:07:09 2009
From: freyr.magnusson at gmail.com (Freyr)
Date: Tue, 14 Jul 2009 16:07:09 -0700 (PDT)
Subject: Passing handlers between bound c++ libs
Message-ID: <3e7b0717-a665-4f42-b7bd-7a99d59258c4@m11g2000yqh.googlegroups.com>

I have a python bound physics library that uses handler to process
events. The passing of handlers between c++ and python causes a huge
overhead slowing down the process.  Can I implement a handler in my
custom python bound c++ lib B and pass it to blackbox python bound c++
lib A so that A would call B directly without passing through the
python layer?  Or to phrase the question differently:  Can I pass a
handler from B through python to A so that A will invoke B with out
calling into python code?


From lists at cheimes.de  Tue Jul 14 19:08:24 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 15 Jul 2009 01:08:24 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
Message-ID: <h3j358$lhr$1@ger.gmane.org>

Chris Rebert wrote:
> Using the xor bitwise operator is also an option:
> bool(x) ^ bool(y)

I prefer something like:

    bool(a) + bool(b) == 1

It works even for multiple tests (super xor):

  if bool(a) + bool(b) + bool(c) + bool(d) != 1:
      raise ValueError("Exactly one of a, b, c and d must be true")

Christian



From darkwater42 at gmail.com  Tue Jul 14 19:08:36 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 16:08:36 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
Message-ID: <95f25380-d71f-41b6-82b8-f991551e8a1a@32g2000yqj.googlegroups.com>

On Jul 14, 8:10?am, Piet van Oostrum <p... at cs.uu.nl> wrote:

> Of course you can take any BST algorithm and replace pointers by indices
> in the array and allocate new elements in the array. But then you need
> array elements to contain the indices for the children explicitely.

And why is this a problem? This is how binary heaps are typically
implemented, and it all works swimmingly. The node rotations for
keeping a binary heap balanced turn out to be suitable for
representation in a flat array. I.e., when you do the node rotations,
you only ever have to copy log n array elements.

In general, however, you can't move nodes around so easily when
represented in a flat array. A node movement in a tree represented
with pointers, might involves changing just two pointers, while when
represented as a flat array, might involve copying most of the array
to maintain the tree invariants. It just so turns out that maintaining
the invariants for a binary heap does not have this issue.

This is why I was curious about treaps, which are a type of binary
heap. The CLRS textbook on algorithms discusses treaps, but doesn't
ever mention whether they are as fortunate as less constrained binary
heaps. I'm sure I could work out for myself whether the treap
rotations are suitable for storage in a flat array, but I might make a
mistake somewhere in my reasoning, and then never know the true
answer!

|>ouglas


From Scott.Daniels at Acm.Org  Tue Jul 14 19:17:35 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 16:17:35 -0700
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <h3iptj$ave$1@panix3.panix.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
	<h3iptj$ave$1@panix3.panix.com>
Message-ID: <AsedncM--I7RjcDXnZ2dnUVZ_rudnZ2d@pdx.net>

Aahz wrote:
> In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
> Stefan Behnel  <stefan_ml at behnel.de> wrote:
>> Deep_Feelings wrote:
>>> So you have chosen programming language "x" so shall you tell us why
>>> you did so , and  what negatives or positives it has ?
>> *duck*
> 
> Where do you get the duck programming language?

It shares a type system with Python, of course.  :-)

--Scott David Daniels
Scott.Daniels at Acm.Org


From jackdied at gmail.com  Tue Jul 14 19:23:31 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Tue, 14 Jul 2009 19:23:31 -0400
Subject: decorators - would be nice if...
In-Reply-To: <4A5CFC53.7050902@seehart.com>
References: <4A5CFC53.7050902@seehart.com>
Message-ID: <b8e622740907141623w21a7ef25tde398964eebfc5a5@mail.gmail.com>

On Tue, Jul 14, 2009 at 5:44 PM, Ken Seehart<ken at seehart.com> wrote:
> Almost every time I use decorators, I find myself wishing I had access
> to the local namespace of the context from which the decorator is
> executed. ?In practice, decorator is being applied to a method, so the
> namespace in question would be the dictionary of the class being created.

As other mentioned, an example would make it clearer what you are trying to do.

> Similarly, before decorators were around, I often found myself lamenting
> the fact that a class is not created until after it's scope is
> completed, since this makes certain kinds of metaprogramming more
> difficult. ?But after digging deeper, I realized why it is the way it
> is, so I don't complain about that.

Py3k to the rescue!  Because the metaclass is defined outside of the
class body it is possible to pass in a metaclass that uses a custom
dictionary.  This was added to make some common cases easier (like
knowing in which order members were defined).  This is not
backportable to 2.6 because the __metaclass__ is defined inside the
class body and possibly anywhere in the class body.

-Jack


From darkwater42 at gmail.com  Tue Jul 14 19:23:58 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 16:23:58 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl> <xcadneiIYYK1GcHXnZ2dnUVZ_qadnZ2d@pdx.net>
Message-ID: <5e8d271a-e3e7-451b-92ca-b5321da9b706@o6g2000yqj.googlegroups.com>

On Jul 14, 9:19?am, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:

> It may well be that there is no good simple solution, and people avoid
> writing about non-existent algorithms.

I can't imagine why that should be the case. The CLRS textbook on
algorithms, for instance, goes to some pains to mathematically prove
that there is no comparison sort that can operate in faster than O(n
log n) time.

And any decent discussion of rabies would be sure to mention that
there is no known cure.

CLRS talks about binary heaps, binary search trees, and treaps, and it
shows how to maintain a binary heap in a flat array efficiently (n log
n time overall), but it never even seems to bring up the subject as to
whether a binary search tree or a treap can also be efficiently
maintained in a flat array.

Though it may be the case that these questions are left as exercises
for the student, and therefore buried in the exercises and problem
sets that I didn't read carefully.

> Piet van Oostrum wrote:

> > Of course you can take any BST algorithm and replace pointers by indices
> > in the array and allocate new elements in the array. But then you need
> > array elements to contain the indices for the children explicitely.

> And you loower your locality of reference (cache-friendliness).
> Note the insert in Python, for example, is quite cache-friendly.

I can't see that a binary search tree would typically have
particularly good cache-friendliness, so I can't see why a flat-array
representation, such as is done for a binary heap, would have
particularly worse cache-reference.

|>ouglas


From clp2 at rebertia.com  Tue Jul 14 19:31:25 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 16:31:25 -0700
Subject: Calling functions: Why this complicated ?
In-Reply-To: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
Message-ID: <50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>

On Tue, Jul 14, 2009 at 1:40 PM, Mohan Parthasarathy<suruti94 at gmail.com> wrote:
> Hi,
> I am a newbie. I am reading
> http://www.network-theory.co.uk/docs/pytut/KeywordArguments.html
> Defining a function with "N" arguments and calling them in "M" different
> ways. Why does it have to be this complicated ? I like the idea of calling
> the function by explicitly naming the arguments, but there are so many other
> ways here that is very confusing. Do people really use all these features ?
> Perhaps, there is a equivalent book to "Javascript: Good Parts" for Python ?

Oh $DEITY, don't even compare Python to JavaScript. At least in
Python, when you try to access a non-existent attribute, a proper
NameError exception is thrown rather than silently getting back
"undefined"... (*has traumatic horror story flashback*)

The calling syntax is not so much complicated as it is liberating.
Are you a C junkie who has never heard of named arguments?
    Just use the call sequence like you've always done.
Are you a exacting Smalltalk or Objective-C person who likes to name
all the arguments all the time for clarity?
    You can do that.
Do you want to call a function with lots of default arguments but only
want to override a couple of them?
    Specifying them by name lets you do that succinctly.
Do you not want to have to worry about the order of the parameters
because it seems kinda arbitrary?
    Then specify the arguments by name.
etc...

And if you try and specify an argument twice, Python will throw an
error, so anything truly confusing will get caught right away.
And there's only one definition syntax, so while the call could be
complicated, figuring out what it means by looking to the definition
is fairly easy.

There really aren't that many ways it's done in practice. In practice,
the following styles cover 90% of cases:
- All named arguments: foo(bar=a, baz=b, qux=c)
- All sequential arguments: foo(a, b, c)
- All sequential arguments, with a few optional arguments given by
name: foo(a, b, c, flag=True, style=qux)
- Simple pass-through: foo(*args, **kwargs)

Granted, there's 4 of them, but each taken by itself seems pretty easy
to read, IMHO.

Cheers,
Chris
-- 
http://blog.rebertia.com


From darkwater42 at gmail.com  Tue Jul 14 19:33:33 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 16:33:33 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
	<95f25380-d71f-41b6-82b8-f991551e8a1a@32g2000yqj.googlegroups.com>
Message-ID: <01ea9a41-5885-4df3-91ae-24cfa5bfbec4@y17g2000yqn.googlegroups.com>

I wrote:

> On Jul 14, 8:10?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>
> > Of course you can take any BST algorithm and replace pointers by indices
> > in the array and allocate new elements in the array. But then you need
> > array elements to contain the indices for the children explicitely.


> And why is this a problem?

Oh, I'm sorry -- I see what you are saying now. You're saying you can
just implement a normal binary search tree, but store the tree nodes
in an array, as if it were a chunk of memory, and use array indices as
pointers, rather than using memory addresses as pointers.

Fair enough, but I'm not sure what that would buy you. Other than,
perhaps some improved locality of reference, and the potential to
perhaps get the pointers take up less space if you know the array is
never going to grow to be very large.

|>ouglas



From Scott.Daniels at Acm.Org  Tue Jul 14 19:36:35 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 16:36:35 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <mailman.3114.1247607712.8015.python-list@python.org>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>
	<mailman.3114.1247607712.8015.python-list@python.org>
Message-ID: <06edna4zh5xcicDXnZ2dnUVZ_tKdnZ2d@pdx.net>

Ethan Furman wrote:
>   and returns the last object that is "true"
A little suspect this.
_and_ returns the first object that is not "true," or the last object.
>   or  returns the first object that is "true"
Similarly:
_or_ returns the first object that is "true," or the last object.

> so should xor return the only object that is "true", else False/None?

Xor has the problem that in two cases it can return neither of its args.
Not has behavior similar in those cases, and we see it returns False or
True.  The Pythonic solution is therefore to use False.

> def xor(a, b)
>     if a and b:
>         return None
>     elif a:
>         return a
>     elif b:
>         return b
>     else:
>         return None

     def xor(a, b):
         if bool(a) == bool(b):
             return False
         else:
             return a or b

Side-effect counting in applications of bool(x) is ignored here.
If minimizing side-effects is needed:

     def xor(a, b):
         if a:
             if not b:
                 return a
         elif b:
             return b
         return False

--Scott David Daniels
Scott.Daniels at Acm.Org


From ethan at stoneleaf.us  Tue Jul 14 19:48:26 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 16:48:26 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3j358$lhr$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
Message-ID: <4A5D194A.6050301@stoneleaf.us>

Christian Heimes wrote:
> Chris Rebert wrote:
> 
>>Using the xor bitwise operator is also an option:
>>bool(x) ^ bool(y)
> 
> 
> I prefer something like:
> 
>     bool(a) + bool(b) == 1
> 
> It works even for multiple tests (super xor):
> 
>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>       raise ValueError("Exactly one of a, b, c and d must be true")
> 
> Christian
> 

super_xor!  I like it!

In [23]: def super_xor(args, failure=False):
    ....:     found_one = False
    ....:     for item in args:
    ....:         if item:
    ....:             if found_one:
    ....:                 return failure
    ....:             else:
    ....:                 found_one = item
    ....:     return found_one or failure

In [25]: super_xor((0, 1, 0, []))
Out[25]: 1

In [26]: super_xor((0, 1, 0, [],('this',)))
Out[26]: False

In [27]: super_xor((0, {}, 0, [],()))
Out[27]: False

In [16]: def super_or(args, failure=False):
    ....:     for item in args:
    ....:         if item:
    ....:             return item
    ....:     else:
    ....:         return failure
    ....:

In [17]: super_or((None, [], 0, 3, {}))
Out[17]: 3

In [18]: super_or((None, [], 0, (), {}))
Out[18]: False

In [19]: def super_and(args, failure=False):
    ....:     for item in args:
    ....:         if not item:
    ....:             return failure
    ....:     else:
    ....:         return item
    ....:

In [20]: super_and((1, 2, 3))
Out[20]: 3

In [21]: super_and((1, 2, 3, 4))
Out[21]: 4

In [22]: super_and((1, 0, 3, 4))
Out[22]: False

A whole family of supers.  :)

~Ethan~


From ethan at stoneleaf.us  Tue Jul 14 19:53:37 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 16:53:37 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <06edna4zh5xcicDXnZ2dnUVZ_tKdnZ2d@pdx.net>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>	<mailman.3114.1247607712.8015.python-list@python.org>
	<06edna4zh5xcicDXnZ2dnUVZ_tKdnZ2d@pdx.net>
Message-ID: <4A5D1A81.5000406@stoneleaf.us>

Scott David Daniels wrote:
> Ethan Furman wrote:
> 
>>   and returns the last object that is "true"
> 
> A little suspect this.
> _and_ returns the first object that is not "true," or the last object.
> 
>>   or  returns the first object that is "true"
> 
> Similarly:
> _or_ returns the first object that is "true," or the last object.
> 

Thanks for the correction.

~Ethan~

> 
> --Scott David Daniels
> Scott.Daniels at Acm.Org



From magawake at gmail.com  Tue Jul 14 20:11:49 2009
From: magawake at gmail.com (Mag Gam)
Date: Tue, 14 Jul 2009 20:11:49 -0400
Subject: compiling python
Message-ID: <1cbd6f830907141711s4b6dbbe6gd563a3e63fc53b4@mail.gmail.com>

At my university we are trying to compile python with --enable-shared
however when I do a make many things fail. Is it a good idea to
compile python with shared libraries? It seems mod-python needs it
this way.

TIA


From keith at nekotaku.com  Tue Jul 14 20:29:43 2009
From: keith at nekotaku.com (Alagalah)
Date: Tue, 14 Jul 2009 17:29:43 -0700 (PDT)
Subject: Reading floats from Excel using COM
Message-ID: <04a50999-3934-4235-b047-5135d8c71c94@m11g2000yqh.googlegroups.com>

Hi, I am using the Range function to return a tuple from Excel.

The data in the range (nREVENUE) in the excel file is 100.0, 101.0,
102.0, 103.0, 104.0

I can successfully iterate across the tuple and list, but when I try
and cast to a float to do some math, I get:

  File "C:\Python25\lib\site-packages\win32com\client\__init__.py",
line 454, in __getattr__
    raise AttributeError, "'%s' object has no attribute '%s'" % (repr
(self), attr)
AttributeError: '<win32com.gen_py.Microsoft Excel 12.0 Object
Library.Range instance at 0x37766608>' object has no attribute
'__float__'

**** CODE *****
import win32com.client
import os

excel=win32com.client.Dispatch("Excel.Application")
excel.Visible=0
excel.DisplayAlerts=False

#This is the file that contains the macro
xlsname=os.path.join(os.getcwd(),"nametest.xlsx")
nametest=excel.Workbooks.Open(xlsname)

revenue_list=excel.Range("nREVENUE")

revenue=[]
revenue.extend(revenue_list)

for i in range(len(revenue)):
    rev=revenue[i]
    print float(rev)

excel.Quit()
del excel

****************

I need to use COM as I will eventually need formula support, otherwise
I would use xlutils.

Any advice on how to cast the elements to a float would be greatly
appreciated!


From greg at cosc.canterbury.ac.nz  Tue Jul 14 20:32:25 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 15 Jul 2009 12:32:25 +1200
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <7c4mb4F261slsU1@mid.individual.net>

Deep_Feelings wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and  what negatives or positives it has ?

This summarises my reasons for choosing Python
fairly well:

http://www1.american.edu/cas/econ/faculty/isaac/choose_python.pdf

-- 
Greg


From suruti94 at gmail.com  Tue Jul 14 20:42:55 2009
From: suruti94 at gmail.com (Mohan Parthasarathy)
Date: Tue, 14 Jul 2009 17:42:55 -0700
Subject: Calling functions: Why this complicated ?
In-Reply-To: <50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
Message-ID: <89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>

Chris,
Thanks for your clarifications


> > I am a newbie. I am reading
> > http://www.network-theory.co.uk/docs/pytut/KeywordArguments.html
> > Defining a function with "N" arguments and calling them in "M" different
> > ways. Why does it have to be this complicated ? I like the idea of
> calling
> > the function by explicitly naming the arguments, but there are so many
> other
> > ways here that is very confusing. Do people really use all these features
> ?
> > Perhaps, there is a equivalent book to "Javascript: Good Parts" for
> Python ?
>
> Oh $DEITY, don't even compare Python to JavaScript. At least in
> Python, when you try to access a non-existent attribute, a proper
> NameError exception is thrown rather than silently getting back
> "undefined"... (*has traumatic horror story flashback*)


I did not try to compare python to Javascript.  Just because there are ten
different ways of doing certain things, not all of them may be used. Over a
period of time, people tend to use certain features more and more.

Javascript is  a different beast where some of the features need to be
avoided for writing good programs. I don't know anything about python. But
it is possible that there is a subset that people use frequently which may
be sufficient to write good programs. Sure, that would not help me the
python interview test :-)

>
> The calling syntax is not so much complicated as it is liberating.
> Are you a C junkie who has never heard of named arguments?
>    Just use the call sequence like you've always done.
> Are you a exacting Smalltalk or Objective-C person who likes to name
> all the arguments all the time for clarity?
>    You can do that.


That's where I fit. I did not expect to see more than that :-)


> Do you want to call a function with lots of default arguments but only
> want to override a couple of them?
>    Specifying them by name lets you do that succinctly.
> Do you not want to have to worry about the order of the parameters
> because it seems kinda arbitrary?
>    Then specify the arguments by name.
> etc...
>
> And if you try and specify an argument twice, Python will throw an
> error, so anything truly confusing will get caught right away.
> And there's only one definition syntax, so while the call could be
> complicated, figuring out what it means by looking to the definition
> is fairly easy.
>
> There really aren't that many ways it's done in practice. In practice,
> the following styles cover 90% of cases:
> - All named arguments: foo(bar=a, baz=b, qux=c)
> - All sequential arguments: foo(a, b, c)
> - All sequential arguments, with a few optional arguments given by
> name: foo(a, b, c, flag=True, style=qux)

- Simple pass-through: foo(*args, **kwargs)
>
> Granted, there's 4 of them, but each taken by itself seems pretty easy
> to read, IMHO.


So, all four of them above has its use cases in practice i guess.

thanks
mohan



>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/d9a110f8/attachment.html>

From clp2 at rebertia.com  Tue Jul 14 20:44:12 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 17:44:12 -0700
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <7c4mb4F261slsU1@mid.individual.net>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<7c4mb4F261slsU1@mid.individual.net>
Message-ID: <50697b2c0907141744q61489a81t111d4545828d2b09@mail.gmail.com>

On Tue, Jul 14, 2009 at 5:32 PM, greg<greg at cosc.canterbury.ac.nz> wrote:
> Deep_Feelings wrote:
>>
>> So you have chosen programming language "x" so shall you tell us why
>> you did so , and ?what negatives or positives it has ?
>
> This summarises my reasons for choosing Python
> fairly well:
>
> http://www1.american.edu/cas/econ/faculty/isaac/choose_python.pdf

+1 PDF Of The Week

- Chris
-- 
http://blog.rebertia.com


From martin.hellwig at dcuktec.org  Tue Jul 14 20:50:44 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Wed, 15 Jul 2009 01:50:44 +0100
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <h3iptj$ave$1@panix3.panix.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
	<h3iptj$ave$1@panix3.panix.com>
Message-ID: <uYSdndiUF4t7usDXnZ2dnUVZ8nBi4p2d@bt.com>

Aahz wrote:
> In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
> Stefan Behnel  <stefan_ml at behnel.de> wrote:
>> Deep_Feelings wrote:
>>> So you have chosen programming language "x" so shall you tell us why
>>> you did so , and  what negatives or positives it has ?
>> *duck*
> 
> Where do you get the duck programming language?

Probably floated around in the same C.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From sjmachin at lexicon.net  Tue Jul 14 21:05:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 15 Jul 2009 01:05:16 +0000 (UTC)
Subject: Reading floats from Excel using COM
References: <04a50999-3934-4235-b047-5135d8c71c94@m11g2000yqh.googlegroups.com>
Message-ID: <loom.20090715T010230-316@post.gmane.org>

Alagalah <keith <at> nekotaku.com> writes:

> 
> Hi, I am using the Range function to return a tuple from Excel.

[big snip]

Exact duplicate of question asked by "KB" on
http://groups.google.com/group/python-excel ... see my answer there.






From lawson89 at gmail.com  Tue Jul 14 21:34:05 2009
From: lawson89 at gmail.com (Rick Lawson)
Date: Tue, 14 Jul 2009 18:34:05 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
Message-ID: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>

Appreciate any help on this. I am porting an app from Java to python
and need generic object pooling with hooks for object initialization /
cleanup and be able to specify an object timeout.

Thanks !
Rick


From cmpython at gmail.com  Tue Jul 14 21:52:32 2009
From: cmpython at gmail.com (Che M)
Date: Tue, 14 Jul 2009 18:52:32 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <7ba1ea2b-0886-4972-abb3-5dd77a95aa1e@d4g2000yqa.googlegroups.com>

On Jul 14, 11:55?am, Deep_Feelings <doctore... at gmail.com> wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and ?what negatives or positives it has ?

As a hobbyist--and not a real programmer*--I think I chose Python
(I don't really recall now) because of things like:

- There is a good community, including tutor list, etc.
- I wanted something that would run cross-platform (so no Visual
Basic).
- Preferred something free (so no REALBasic).
- I wanted a high level language.
- It seemed easiest to read and learn.  I like mandatory indents, for
example.
- There are a lot of libraries for it with good support.
- I liked the Zen of Python philosophy (to the extent I understood
it).
- Some high profile entities were using it, so it must have something
going for it.
- It was new enough to be a possible improvement over older languages
  while old enough to be established.
- Who can't like a computer language named Python?

Drawbacks:

- AFAIK, running multiple Python apps all show up in the Windows task
manager as
  "python.exe" (common to all non-compiled languages?) instead of the
app's name.
- Distributing as an executable is not as straightforward as I might
hope.
- I wish Python 3 wouldn't break my 2.5 code.
- If it could be quicker (compiled), that would be better. (But
haven't tried
  psyco or Shed Skin, etc.)
- I've found understanding web programming hard, but that might be
just the
  nature of web programming and not a Python thing.
- I wish wxPython had a more complete rich text editor (but overall it
is great).

CM


From http  Tue Jul 14 22:36:22 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 19:36:22 -0700
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
	<xcadneiIYYK1GcHXnZ2dnUVZ_qadnZ2d@pdx.net>
	<5e8d271a-e3e7-451b-92ca-b5321da9b706@o6g2000yqj.googlegroups.com>
Message-ID: <7xab36oeop.fsf@ruckus.brouhaha.com>

Douglas Alan <darkwater42 at gmail.com> writes:
> I can't see that a binary search tree would typically have
> particularly good cache-friendliness, so I can't see why a flat-array
> representation, such as is done for a binary heap, would have
> particularly worse cache-reference.

That is a good point.  Maybe we should be paying more attention to
cache-oblivious algorithms.

  http://en.wikipedia.org/wiki/Cache-oblivious_algorithm

H. Prokop's masters' thesis cited in the wiki article explains the
subject very well.  A fair amount of work has been done on it since
then, but not as much as one might expect.


From davea at dejaviewphoto.com  Tue Jul 14 22:51:25 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Tue, 14 Jul 2009 22:51:25 -0400
Subject: explode()
In-Reply-To: <6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>	<mailman.3019.1247363434.8015.python-list@python.org>	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
Message-ID: <4A5D442D.2040600@dejaviewphoto.com>


> 	The one thing I really dislike about Python over PHP is that
> Python can usually only appear in the cgi directory (unless other
> arragements are made with your hosting provider or if you reconfigure
> Apache on your own server if you have your own).  With PHP, I can put
> them in any folder on my Web site without any problem.  
>
> 	Regards, 
>
>
>
>
> 						Fred 
>
>   
You should talk to your hosting provider.  With mine, all you need do 
differently for directories other than cgi-bin is to do a chmod on the 
file to make it executable.  Have you tried that?  Is it hosted on Unix 
or Windows?

DaveA



From jmcmonagle at NO.SPAM.velseis.com.au  Tue Jul 14 23:06:18 2009
From: jmcmonagle at NO.SPAM.velseis.com.au (John McMonagle)
Date: Wed, 15 Jul 2009 13:06:18 +1000
Subject: Tkinter / Entry widget problem
In-Reply-To: <mailman.3066.1247516702.8015.python-list@python.org>
References: <mailman.3066.1247516702.8015.python-list@python.org>
Message-ID: <4A5D47AA.7090007@NO.SPAM.velseis.com.au>

Andras Szabo wrote:
> Hello. I searched the archives but couldn't find a solution to a problem
> related to the Entry widget in Tkinter.
> 
> When creating a pop-up window in an app, which contains an Entry widget,
> I want this widget to contain some default string, to have all this
> default string selected (as if the user had manually selected
> everything), and to have the focus transferred to this widget.
> 
> (The idea is then that if the window pops up, the user won't have to
> click or press Tab any more before being able to type what is needed in
> the textbox, overwriting what is written there already.)
> 
> I thought this might be the way to go:
> 
> entrybox=Entry(toplevel_parent_window)
> entrybox.insert(0,"Some default string")
> entrybox.select_range(0,END)
> entrybox.focus_set()
> entrybox.pack()
> 
> But it doesn't seem to work - the focus is not transferred to the Entry
> widget, and the text does not appear to be selected (even though after
> this entrybox.selection_present() returns True).
> 
> What am I doing wrong?
> 
> andras

You're probably not updating after the focus_set.

Try the following:

from Tkinter import *
r = Tk()


def click():
    t = Toplevel(r)
    e = Entry(t)
    e.pack()
    b = Button(t, text='Close', command=t.destroy)
    b.pack()
    e.insert(0, 'Default')
    e.select_range(0, END)
    e.focus_set()
    r.update()



b = Button(r, text='Press', command=click)
b.pack()

r.mainloop()



Regards,

John


From davea at ieee.org  Tue Jul 14 23:32:21 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 14 Jul 2009 23:32:21 -0400
Subject: How to keep a function as a generator function when the yield
	operator	is moved into its sub-functions??
In-Reply-To: <4A5CC86A.9070907@lbl.gov>
References: <4A5CC86A.9070907@lbl.gov>
Message-ID: <4A5D4DC5.1090202@ieee.org>

weafon wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Hi guys,
>
> I have a question about the usage of yield. As shown in the below 
> example, in general, if there is a code segment commonly used by two 
> or more functions, we may isolate the segment into a function and then 
> call it from other functions if necessary.
>
> def func1():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
>
>
> def func2():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
>
> def commoncode()
>    AAAA
>    BBBB
>    CCCC
>
> However, if there is a 'yield' operation in the common code segment, 
> the isolation causes that func1 and func2 become a non-generator 
> function!! Although I can prevent such an isolation by just 
> duplicating the segment in func1 and func2 to keep both of them being 
> generator functions, the code may become ugly and hard to maintain 
> particularly when coomoncode() is long.
>
> The problem may be resolved if I can define the commoncode() as an 
> inline function or marco. Unfortunately, inline and marco do not seems 
> to be implemented in python. Thus, how can I isolate a common segment 
> into a function when there are yield operations in the common segment?
>
> Thanks,
> Weafon
>
You are implying there's something special or unique about yield in 
this.  Return has the same problem, and many other flow control 
constructs.   Also, variable definitions and scoping.

So you can't just copy any old bunch of adjacent lines out of two 
functions, put it into a third, and call it factoring.  Give us a 
specific example you're puzzled about, and we can try to solve it.

DaveA



From pfeldman at verizon.net  Wed Jul 15 00:07:14 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Tue, 14 Jul 2009 21:07:14 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5CFF83.9070301@mrabarnett.plus.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
Message-ID: <24491580.post@talk.nabble.com>


I appreciate the effort that people have made, but I'm not impressed with any
of the answers.  For one thing, xor should be able to accept an arbitrary
number of input arguments (not just two), and should return True if and only
if the number of input arguments that evaluate to True is odd (see
www.mathworld.com article on xor).  Here's my code:

def xor(*args):
   """xor accepts an arbitrary number of input arguments, returning True
   if and only if bool() evaluates to True for an odd number of the input
   arguments."""

   result= False

   for arg in args:
      if bool(arg): result= not result

   return result



MRAB-2 wrote:
> 
> Ethan Furman wrote:
>> Robert Kern wrote:
>>> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
>>>
>>>> != does do what I want, except that it doesn't indicate to someone 
>>>> reading
>>>> the code that the operands are being treated as logicals.  
>>>> (Readability is
>>>> supposed to be one of the major selling points of Python).  But, this
>>>> is
>>>> probably good enough.
>>>
>>>
>>> In the words of those greater than myself, "Not every one-liner needs 
>>> to be in the standard library."
>>>
>>> def xor(a, b):
>>>     return bool(a) != bool(b)
>>>
>> 
>> Let's see...
>> 
>>   and returns the last object that is "true"
>>   or  returns the first object that is "true"
>> 
>> so should xor return the only object that is "true", else False/None?
>> 
>> def xor(a, b)
>>     if a and b:
>>         return None
>>     elif a:
>>         return a
>>     elif b:
>>         return b
>>     else:
>>         return None
>> 
> How about:
> 
> def xor(a, b):
>      return not b and a or not a and b
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24491580.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From milesck at umich.edu  Wed Jul 15 01:08:42 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 01:08:42 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <24491580.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
	<24491580.post@talk.nabble.com>
Message-ID: <9F28E417-53B9-4CFE-A880-965B85903B34@umich.edu>

On Jul 15, 2009, at 12:07 AM, Dr. Phillip M. Feldman wrote:

> I appreciate the effort that people have made, but I'm not impressed  
> with any
> of the answers.  For one thing, xor should be able to accept an  
> arbitrary
> number of input arguments (not just two)

You originally proposed this in the context of the existing short- 
circuit boolean operators.  Those operators (being infix) take only  
two operands.

> and should return True if and only
> if the number of input arguments that evaluate to True is odd

The existing and/or operators always return the value of one of the  
operands--not necessarily True or False--which is another important  
property, but one that can't be translated fully to xor.  Given the  
lack of context in your original post, hopefully you'll forgive me  
being unimpressed by your not being impressed. :)

> Here's my code:
>
> def xor(*args):
>   """xor accepts an arbitrary number of input arguments, returning  
> True
>   if and only if bool() evaluates to True for an odd number of the  
> input
>   arguments."""
>
>   result= False
>
>   for arg in args:
>      if bool(arg): result= not result
>
>   return result

If all you want is a True or False result, I'd write it like this:

import operator
def xor(*args):
     return reduce(operator.xor, map(bool, args)) # or imap

In order to make it act more like the other logical operators, I'd use  
MRAB's 2-argument xor as the reducer--though I can't really see the  
utility.

def xor2(a, b):
     return (not b and a) or (not a and b)

def xor(*args):
     return reduce(xor2, args)

You may also find this question interesting:

http://stackoverflow.com/questions/432842/

-Miles



From amrita at iisermohali.ac.in  Wed Jul 15 02:13:06 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Wed, 15 Jul 2009 11:43:06 +0530 (IST)
Subject: one more question
Message-ID: <20300.210.212.36.65.1247638386.squirrel@www.iisermohali.ac.in>


Dear all,

Just one more thing i want to ask that suppose i have a file like:---


 47     8   ALA       H     H      7.85     0.02     1
 48     8   ALA       HA    H      2.98     0.02     1
 49     8   ALA       HB    H      1.05     0.02     1
 50     8   ALA       C     C    179.39      0.3     1
 51     8   ALA       CA    C     54.67      0.3     1
 52     8   ALA       CB    C     18.85      0.3     1
 53     8   ALA       N     N    123.95      0.3     1
107    15   ALA       H     H      8.05     0.02     1
108    15   ALA       HA    H      4.52     0.02     1

now what i want that i will make another file in which first it will write
the position of ALA lets say 8 then its name ALA and then the chemical
shift value for only three atoms C,CA and CB.

Means it will be someting like:

8  ALA  C = 179.39  CA = 54.67  CB = 18.85

I tried but its not coming.


Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From mensanator at aol.com  Wed Jul 15 02:21:21 2009
From: mensanator at aol.com (Mensanator)
Date: Tue, 14 Jul 2009 23:21:21 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com> 
	<7xab37t843.fsf@ruckus.brouhaha.com>
Message-ID: <d2872b96-3a01-437e-a83f-6fd774bb367a@n11g2000yqb.googlegroups.com>

On Jul 14, 1:47?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Mensanator <mensana... at aol.com> writes:
> > - unlimited precision integers
> > - easy to program
> > - IDE not required
> > - reasonable speed
> > - math library needs to include number theoretic functions
> > ? like GCD, LCM, Modular Inverse, etc.
> > - not fucking retarded like F#
>
> Have you looked at Haskell?
>
> > As for negatives, the GMP library doesn't factor.
>
> Maybe with some MIRACL bindings...

That's the factoring program (factor.exe from
the MIRACL package) I made reference to.

I don't know how to fix the bug nor how to bind
it to Python.

What I do (or did at one time) know is how figure
out how to recompile it, change the output to be
database compatible, consistent messages rather
than such useless messages as "this number is prime".

The Python program, as it captures the StdOut,
can watch for the bug. The bug is that factor.exe
occasionally gets stuck on a composite while deep
into the factoring process. Sometimes, however,
this getting stuck can be resolved if you send the
composite back to the beginning and start over.
The factor.exe program isn't smart enough to try
this, it simply returns COMPOSITE amongst the
PRIME_FACTORS. The calling Python program can then
collect the unfactored composites and call factor.exe
again with each of them sending them back to the
start of the factoring. If they successfully factor
on the second pass, Python then appends them to
the factors from the first pass to achieve a complete
factorization that factor.exe can produce in theory
but not in practice.


From mensanator at aol.com  Wed Jul 15 02:35:15 2009
From: mensanator at aol.com (Mensanator)
Date: Tue, 14 Jul 2009 23:35:15 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com> 
	<7xab37t843.fsf@ruckus.brouhaha.com>
	<pan.2009.07.14.21.58.28.860000@nowhere.com>
Message-ID: <4b2e00a3-d09c-4c9a-bcfb-8c89af262963@i6g2000yqj.googlegroups.com>

On Jul 14, 4:58?pm, Nobody <nob... at nowhere.com> wrote:
> On Tue, 14 Jul 2009 11:47:08 -0700, Paul Rubin wrote:
> >> - unlimited precision integers
> >> - easy to program
> >> - IDE not required
> >> - reasonable speed
> >> - math library needs to include number theoretic functions
> >> ? like GCD, LCM, Modular Inverse, etc.
> >> - not fucking retarded like F#
>
> > Have you looked at Haskell?
>
> Given his comment about F#, I have a suspicion that he might be
> dogmatically opposed to functional languages generally.

Not dogmatically opposed, I installed it because
I actually wanted to try functional progrsmming.
My mistake was listening to that Harrop dude who
didn't bother to explain that F# is part of a
government program that provides jobs for retards.

To wit: F# has a rational data type, that's cool.
But wait, F# has TWO rational data types. Huh?
Well, after they made the first, some jackass
came up with a second type that stores data more
efficiently.

And, of course, the second type doesn't have the
same functionality as the first, so you need both.

And of the myriad data type converion methods, guess
which possible conversion methods are conspicuous
by their absense? That's right, type1 <==> type2
rational conversions don't exist.

At that point, I decided I wasn't going to put up
crap like that and threw it away.


From timr at probo.com  Wed Jul 15 02:43:10 2009
From: timr at probo.com (Tim Roberts)
Date: Tue, 14 Jul 2009 23:43:10 -0700
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<mailman.3110.1247601365.8015.python-list@python.org>
Message-ID: <ueuq55t6f4sjqut49o92gkq263ad1u2f0q@4ax.com>

"Dr. Phillip M. Feldman" <pfeldman at verizon.net> wrote:
>
>Here's a related issue: I would like to see an option for type checking on
>operands of logical operators, so that attempting to apply a logical
>operator to non-Boolean entities generates a warning message.  With operand
>type checking, 'xor' and != would be different.

How would you define "Boolean entities"?  Do you mean the True and False
values?  Such a change would break virtually every Python program ever
written.

In any case, this idea is dead in the water.  It would break a whole bunch
of existing code from before the conditional operator:

    xxx = testme and truevalue or falsevalue
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From wuwei23 at gmail.com  Wed Jul 15 02:50:08 2009
From: wuwei23 at gmail.com (alex23)
Date: Tue, 14 Jul 2009 23:50:08 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org>
Message-ID: <045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com>

amr... at iisermohali.ac.in wrote:
> I tried but its not coming.

How much are you prepared to pay for help with this? Or are you just
asking us to do all the work for you?


From wuwei23 at gmail.com  Wed Jul 15 02:56:57 2009
From: wuwei23 at gmail.com (alex23)
Date: Tue, 14 Jul 2009 23:56:57 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com>
Message-ID: <c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com>

On Jul 15, 4:50?pm, alex23 <wuwe... at gmail.com> wrote:
> amr... at iisermohali.ac.in wrote:
> > I tried but its not coming.
>
> How much are you prepared to pay for help with this? Or are you just
> asking us to do all the work for you?

Or to be a _little_ less blunt: if you want people here to _assist_
you with _your_ code, then post what you've tried here, along with
tracebacks if errors are occurring, or an explanation as to what it
isn't doing that you require.

Spawning a new thread restating your question every time someone
suggests you RTFM isn't the best way to show that you're actually
trying to solve this issue yourself.


From clp2 at rebertia.com  Wed Jul 15 03:05:14 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 00:05:14 -0700
Subject: one more question
In-Reply-To: <20300.210.212.36.65.1247638386.squirrel@www.iisermohali.ac.in>
References: <20300.210.212.36.65.1247638386.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907150005q30917bf1i88cde982b54a3bdf@mail.gmail.com>

On Tue, Jul 14, 2009 at 11:13 PM, <amrita at iisermohali.ac.in> wrote:
>
> Dear all,
>
> Just one more thing i want to ask that suppose i have a file like:---
>
>
> ?47 ? ? 8 ? ALA ? ? ? H ? ? H ? ? ?7.85 ? ? 0.02 ? ? 1
> ?48 ? ? 8 ? ALA ? ? ? HA ? ?H ? ? ?2.98 ? ? 0.02 ? ? 1
> ?49 ? ? 8 ? ALA ? ? ? HB ? ?H ? ? ?1.05 ? ? 0.02 ? ? 1
> ?50 ? ? 8 ? ALA ? ? ? C ? ? C ? ?179.39 ? ? ?0.3 ? ? 1
> ?51 ? ? 8 ? ALA ? ? ? CA ? ?C ? ? 54.67 ? ? ?0.3 ? ? 1
> ?52 ? ? 8 ? ALA ? ? ? CB ? ?C ? ? 18.85 ? ? ?0.3 ? ? 1
> ?53 ? ? 8 ? ALA ? ? ? N ? ? N ? ?123.95 ? ? ?0.3 ? ? 1
> 107 ? ?15 ? ALA ? ? ? H ? ? H ? ? ?8.05 ? ? 0.02 ? ? 1
> 108 ? ?15 ? ALA ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
>
> now what i want that i will make another file in which first it will write
> the position of ALA lets say 8 then its name ALA and then the chemical
> shift value for only three atoms C,CA and CB.
>
> Means it will be someting like:
>
> 8 ?ALA ?C = 179.39 ?CA = 54.67 ?CB = 18.85
>
> I tried but its not coming.

Surely a colleague at IISER Mohali's Computer Science department
should be able to help you?

Cheers,
Chris
-- 
http://blog.rebertia.com

From koranthala at gmail.com  Wed Jul 15 03:24:52 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 00:24:52 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org>
Message-ID: <19b3cb31-643c-47f4-9153-52e15289e933@24g2000yqm.googlegroups.com>

On Jul 15, 11:13?am, amr... at iisermohali.ac.in wrote:
> Dear all,
>
> Just one more thing i want to ask that suppose i have a file like:---
>
> ?47 ? ? 8 ? ALA ? ? ? H ? ? H ? ? ?7.85 ? ? 0.02 ? ? 1
> ?48 ? ? 8 ? ALA ? ? ? HA ? ?H ? ? ?2.98 ? ? 0.02 ? ? 1
> ?49 ? ? 8 ? ALA ? ? ? HB ? ?H ? ? ?1.05 ? ? 0.02 ? ? 1
> ?50 ? ? 8 ? ALA ? ? ? C ? ? C ? ?179.39 ? ? ?0.3 ? ? 1
> ?51 ? ? 8 ? ALA ? ? ? CA ? ?C ? ? 54.67 ? ? ?0.3 ? ? 1
> ?52 ? ? 8 ? ALA ? ? ? CB ? ?C ? ? 18.85 ? ? ?0.3 ? ? 1
> ?53 ? ? 8 ? ALA ? ? ? N ? ? N ? ?123.95 ? ? ?0.3 ? ? 1
> 107 ? ?15 ? ALA ? ? ? H ? ? H ? ? ?8.05 ? ? 0.02 ? ? 1
> 108 ? ?15 ? ALA ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
>
> now what i want that i will make another file in which first it will write
> the position of ALA lets say 8 then its name ALA and then the chemical
> shift value for only three atoms C,CA and CB.
>
> Means it will be someting like:
>
> 8 ?ALA ?C = 179.39 ?CA = 54.67 ?CB = 18.85
>
> I tried but its not coming.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA

This is indeed possible and should be quite easy. One problem is that
I do not exactly understand the problem - how do you decide which all
to join and print? Is it ALA with 4th field as C or 6th field as 0.3?
The issue here is that I am not getting the context of your problem.
And I have *no* idea about the Chemical shift etc which you are
talking about.
If you can explain it a little more, I will try something out.

Just for the scenario you explained, this code will suffice -
f = open('abcd')
d = {}
for line in f:
    fields = line.split()
    if fields[2] == 'ALA':
        d.setdefault('ALA', {'position':fields[1], 'values':[]})
        if fields[4] == 'C':
            d['ALA']['values'].append({fields[3]:fields[5]})

print d

But i dont think this is what you want


From piet at cs.uu.nl  Wed Jul 15 03:42:15 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 09:42:15 +0200
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
	<95f25380-d71f-41b6-82b8-f991551e8a1a@32g2000yqj.googlegroups.com>
	<01ea9a41-5885-4df3-91ae-24cfa5bfbec4@y17g2000yqn.googlegroups.com>
Message-ID: <m2zlb6xui0.fsf@cs.uu.nl>

>>>>> Douglas Alan <darkwater42 at gmail.com> (DA) wrote:

>DA> I wrote:
>>> On Jul 14, 8:10?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>>> 
>>> > Of course you can take any BST algorithm and replace pointers by indices
>>> > in the array and allocate new elements in the array. But then you need
>>> > array elements to contain the indices for the children explicitely.


>>> And why is this a problem?

>DA> Oh, I'm sorry -- I see what you are saying now. You're saying you can
>DA> just implement a normal binary search tree, but store the tree nodes
>DA> in an array, as if it were a chunk of memory, and use array indices as
>DA> pointers, rather than using memory addresses as pointers.

>DA> Fair enough, but I'm not sure what that would buy you. Other than,
>DA> perhaps some improved locality of reference, and the potential to
>DA> perhaps get the pointers take up less space if you know the array is
>DA> never going to grow to be very large.

My second sentence that you quoted more or less means `it doesn't buy
you much'. 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From dickinsm at gmail.com  Wed Jul 15 03:44:48 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Wed, 15 Jul 2009 00:44:48 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org> 
	<4A5CFAC4.7020300@stoneleaf.us> <4A5CFF83.9070301@mrabarnett.plus.com> 
	<mailman.3132.1247630837.8015.python-list@python.org>
Message-ID: <0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>

On Jul 15, 5:07?am, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> I appreciate the effort that people have made, but I'm not impressed with any
> of the answers. ?For one thing, xor should be able to accept an arbitrary
> number of input arguments (not just two), and should return True if and only
> if the number of input arguments that evaluate to True is odd.

Well, that's not exactly what you originally asked for.  But it's
still a one-liner:

def xor(*args): return bool(sum(map(bool, args)) % 2)

or perhaps

def xor(*args): return bool(len(filter(None, args)) & 1)

> Here's my code:
>
> def xor(*args):
> ? ?"""xor accepts an arbitrary number of input arguments, returning True
> ? ?if and only if bool() evaluates to True for an odd number of the input
> ? ?arguments."""
>
> ? ?result= False
>
> ? ?for arg in args:
> ? ? ? if bool(arg): result= not result

It's more idiomatic to say "if arg: ..." rather than "if bool
(arg): ...".

>
> ? ?return result

Mark


From koranthala at gmail.com  Wed Jul 15 03:51:23 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 00:51:23 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com>
Message-ID: <56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com>

On Jul 15, 11:56?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 15, 4:50?pm, alex23 <wuwe... at gmail.com> wrote:
>
> > amr... at iisermohali.ac.in wrote:
> > > I tried but its not coming.
>
> > How much are you prepared to pay for help with this? Or are you just
> > asking us to do all the work for you?
>
> Or to be a _little_ less blunt: if you want people here to _assist_
> you with _your_ code, then post what you've tried here, along with
> tracebacks if errors are occurring, or an explanation as to what it
> isn't doing that you require.
>
> Spawning a new thread restating your question every time someone
> suggests you RTFM isn't the best way to show that you're actually
> trying to solve this issue yourself.

Alex,
   I am not sure about it. It doesnt look like she(I guess) is a
programmer. In the last thread, she asked the question and the reply
was to check up the regular expressions. Now, for a non-programmer, re
might be a real confusing and tough subject to grasp.
   I am not saying that what you said was wrong, only that I felt that
she got tense looking up regular expressions. So a python reply which
basically does the basic checking without going to re etc might be
more helpful for her to start her own coding.


From piet at cs.uu.nl  Wed Jul 15 04:14:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 10:14:20 +0200
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <m24otg3hkk.fsf@cs.uu.nl>
	<h3i9v6$c5t$1@panix3.panix.com> <m27hybyo95.fsf@cs.uu.nl>
	<h3j2hu$nmf$1@panix3.panix.com>
Message-ID: <m2vdluxt0j.fsf@cs.uu.nl>

>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:

>A> In article <m27hybyo95.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>>> 
>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>A> <piet at cs.uu.nl> wrote: 
>>> 
>>>>>> And to get c.x = 4 working you also need a __setitem__. 
>>> 
>A> Nope.  You do need __setitem__ so that this works:
>>> 
>A> c['x'] = 4
>>> 
>>> Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
>>> that was what the OP wanted (I think).

>A> c.x = 4 
>A> already updates the instance dict, so there's no need to change any class
>A> methods to support it.  That is, IME it's much better to add methods to
>A> a regular class to make it more dict-like using the built-in instance
>A> dict rather than changing any of the attribute mechanisms.  If you're
>A> really curious, I recommend trying several approaches yourself to see
>A> what works better.  ;-)

Yes, that's why I mentioned __setitem__. I just mixed up the motivation.

In [28]: class AttrDict:
   ....:     def __getitem__(self, key):
   ....:         return getattr(self, key)
   ....:     
   ....:     def __setitem__(self, key, value):
   ....:         setattr(self, key, value)
   ....:         
   ....:         

In [29]: c = AttrDict()

In [30]: c["y"] = 3

In [31]: c.y
Out[31]: 3

In [32]: c.x = 4

In [33]: c['x']
Out[33]: 4

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From hackingkk at gmail.com  Wed Jul 15 04:22:24 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Wed, 15 Jul 2009 13:52:24 +0530
Subject: select lines in python
In-Reply-To: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
References: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
Message-ID: <1247646144.3355.26.camel@krishna-laptop>

On Tue, 2009-07-14 at 23:03 +0530, amrita at iisermohali.ac.in wrote:
> Dear all,
> 
> Can anyone tell me that suppose i have a file having content like:
> 
>     _Atom_name
>       _Atom_type
>       _Chem_shift_value
>       _Chem_shift_value_error
>       _Chem_shift_ambiguity_code
>      1     1   PHE       H     H      8.49     0.02     1
>      2     1   PHE       HA    H      4.60     0.02     1
>      3     1   PHE       CA    C     57.83      0.3     1
>      4     2   LEU       H     H      8.23     0.02     1
>      5     2   LEU       HA    H      4.25     0.02     1
>      6     2   LEU       HB2   H      1.54     0.02     1
>      7     3   ASP       H     H      8.10     0.02     1
>      8     3   ASP       HA    H      4.52     0.02     1
>      9     3   ASP       HB2   H      2.65     0.02     1
> stop
> 
> 
> now what i want that instead of copying all the lines it will just write
> the information about PHE and ASP then how i acn do that using python
> programming.Kindly tell me the command for that.

Dear Amrita,
No one will tell you commands for your program.
We can give you logic and the way to implement it.
It is recommended that you write the code your self.
For our problem you keep a list and do a readlines() function and get
the content in your list variable.
then start looping through that list like for line in lines: where the
lines variable is your list.
Now keep comparing each line against your expected phrase and the moment
you find one, do the actions you need such as writing to a file.

happy hacking.
Krishnakant.
 



From andi at mozarellasalat.homelinux.net  Wed Jul 15 04:24:22 2009
From: andi at mozarellasalat.homelinux.net (Andreas Grommek)
Date: Wed, 15 Jul 2009 10:24:22 +0200
Subject: promlems with threading and print
Message-ID: <4A5D9236.9060008@mozarellasalat.homelinux.net>

Hi Newsgroup,

I'm new to python and I am familiarizing myself with threads (haven't done any threading in any
other language before...). I was playing around and discovered some weird behavior. Here is my code:

import threading
from time import sleep
from random import random
import sys

class MyThread(threading.Thread):

    def __init__(self, t, s):
        self.threadmarker = t
        self.sleeptime = s
        threading.Thread.__init__(self)

    def run(self):
        print("Tread", self.threadmarker, "is going to sleep for a while...")
        sys.stdout.flush()     #flush I/O
        sleep(self.sleeptime)  #go to sleep
        print("Tread", self.threadmarker, "is waking up and terminating")

a = 1
b = 20
for n in range(a, b):
   x = MyThread(n,random()*10.0)
   x.start()


This should create some threads which print messages, go to sleep for a random amount of time (max
10 seconds) and return with a message. When I run the code I get something like this (always different):

Tread 1 is going to sleep for a while...
Tread 2 is going to sleep for a while...
Tread 3 is going to sleep for a while...
Tread 4 is going to sleep for a while...
Tread 5 is going to sleep for a while...
Tread 6 is going to sleep for a while...
Tread 6 is going to sleep for a while...
Tread 7 is going to sleep for a while...
Tread 7 is going to sleep for a while...
Tread 7 is going to sleep for a while...
Tread 8 is going to sleep for a while...
(...)

Some "going to sleep" messages appear more than once. If I increase the number of thread the problem
gets worse and threads are even started out of order (but this alone would not worry me...).

Are some threads startet more than once or is this an issue with print? What else can I do in
addition to sys.stdout.flush() after the first print statement? Are print and sleep thread-safe? Or
is this a bug (I use python 3.1)

Any hints and help for an newbie would be appreciated.

Thanks,
Andi


From p.f.moore at gmail.com  Wed Jul 15 04:31:13 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Wed, 15 Jul 2009 09:31:13 +0100
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <AsedncM--I7RjcDXnZ2dnUVZ_rudnZ2d@pdx.net>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
	<h3iptj$ave$1@panix3.panix.com>
	<AsedncM--I7RjcDXnZ2dnUVZ_rudnZ2d@pdx.net>
Message-ID: <79990c6b0907150131x73370fa3iaa095564fe729a51@mail.gmail.com>

2009/7/15 Scott David Daniels <Scott.Daniels at acm.org>:
> Aahz wrote:
>>
>> In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
>> Stefan Behnel ?<stefan_ml at behnel.de> wrote:
>>>
>>> Deep_Feelings wrote:
>>>>
>>>> So you have chosen programming language "x" so shall you tell us why
>>>> you did so , and ?what negatives or positives it has ?
>>>
>>> *duck*
>>
>> Where do you get the duck programming language?
>
> It shares a type system with Python, of course. ?:-)

No, it just has a type system with all the same operations as Python,
which all do the same things. :-)

Paul.


From alessiogiovanni.baroni at gmail.com  Wed Jul 15 04:41:49 2009
From: alessiogiovanni.baroni at gmail.com (tuxagb)
Date: Wed, 15 Jul 2009 01:41:49 -0700 (PDT)
Subject: A question of style .....
Message-ID: <430dc862-7c94-4616-a66c-5ed2c033442f@n11g2000yqb.googlegroups.com>

If I have to write an extension module with many objects, how can I
organizing the code?
I think: every object in a separate file, and a last file with the
PyInit_..... function. But is unmenageable .....

Solutions?

Thanks!


From jgardner at jonathangardner.net  Wed Jul 15 04:53:51 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Wed, 15 Jul 2009 01:53:51 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
Message-ID: <38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>

On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
> Appreciate any help on this. I am porting an app from Java to python
> and need generic object pooling with hooks for object initialization /
> cleanup and be able to specify an object timeout.
>

Are you looking for something like a thread pool or a connection pool?
Such a thing is easy to code in Python. Might as well write one from
scratch for your particular need.

By the way, a tip for writing Python: Forget Java. If you're porting
an app, consider rewriting it from the architecture on up. You'll save
yourself time and get a better result.


From afriere at yahoo.co.uk  Wed Jul 15 04:55:33 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Wed, 15 Jul 2009 01:55:33 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org> 
	<4A5CFAC4.7020300@stoneleaf.us> <4A5CFF83.9070301@mrabarnett.plus.com> 
	<mailman.3132.1247630837.8015.python-list@python.org>
	<0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>
Message-ID: <ee4ab06b-8f38-40c9-bf5a-fccd936a8432@d32g2000yqh.googlegroups.com>

On Jul 15, 5:44?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 15, 5:07?am, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
> wrote:

[snip]

> > ? ?for arg in args:
> > ? ? ? if bool(arg): result= not result
>
> It's more idiomatic to say "if arg: ..." rather than "if bool
> (arg): ...".
>

Ah yes, but not once conditional tests, (just like logical operators),
type-check to ensure they have been supplied with Boolean entities. ;)


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 15 04:58:36 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 15 Jul 2009 08:58:36 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<pan.2009.07.14.09.14.52@REMOVE.THIS.cybersource.com.au>
	<ba24b9b8-f95d-4217-8e43-0fed8f4034b5@s6g2000vbp.googlegroups.com>
Message-ID: <pan.2009.07.15.08.58.36@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 08:53:33 -0700, Carl Banks wrote:

> On Jul 14, 2:14?am, Steven D'Aprano
> <ste... at REMOVE.THIS.cybersource.com.au> wrote:
>> On Tue, 14 Jul 2009 01:30:48 -0700, Carl Banks wrote:
>> > Seriously, do you *ever* take more than 2 seconds to consider whether
>> > you might be missing something obvious before following up with these
>> > indignant knee-jerk responses?
>>
>> Obviously not.
>>
>> [...]
>>
>> > Or would you rather let all unexpected exceptions print to standard
>> > error, which is often a black hole in non-interactive sitations?
>>
>> Fair point. Of course you're right.
> 
> I don't want to be mean or anything.  I agree with you on 95% of issues
> probably, of course I only follow up to disagree....


No problem Carl. You were right, in this instance I was being a smartarse 
and ended up being too clever for my own good. There are cases where you 
want to catch all exceptions, not to hide them, but to process them in 
some way (possibly logging the error and then exiting).



-- 
Steven


From jeremiah.dodds at gmail.com  Wed Jul 15 05:01:55 2009
From: jeremiah.dodds at gmail.com (Jeremiah Dodds)
Date: Wed, 15 Jul 2009 10:01:55 +0100
Subject: Calling functions: Why this complicated ?
In-Reply-To: <89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
	<89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
Message-ID: <12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>

On Wed, Jul 15, 2009 at 1:42 AM, Mohan Parthasarathy <suruti94 at gmail.com>wrote:

> So, all four of them above has its use cases in practice i guess.
>
> thanks
> mohan
>

As a hopefully semi-informative aside, I've been writing python code for a
few years now, and I regularly use all four forms of argument passing listed
above.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090715/284d3486/attachment.html>

From jgardner at jonathangardner.net  Wed Jul 15 05:02:04 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Wed, 15 Jul 2009 02:02:04 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3122.1247615131.8015.python-list@python.org>
Message-ID: <4c01f2c4-314d-4690-8904-d19dec9f6241@k1g2000yqf.googlegroups.com>

On Jul 14, 4:48?pm, Ethan Furman <et... at stoneleaf.us> wrote:
>
> A whole family of supers. ?:)
>

You should pick up Lisp. The whole concept of a binary operator
doesn't exist over there. All the things binary operators can do, Lisp
does with 0, 1, 2, or more arguments.

[1]> (+)
0
[2]> (+ 1)
1
[3]> (+ 1 2)
3
[4]> (+ 1 2 3)
6

Once you get used to that, binary operators don't seem so useful
anymore.

The equivalent in Python is dropping the operators and replacing them
with built-in functions that take 0, 1, 2, or more arguments.


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 15 05:11:44 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 15 Jul 2009 09:11:44 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
Message-ID: <pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:

> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
> to have an 'xor' operator as well.

I've often wished there was too, for the sake of completeness and 
aesthetics, I'd love to be able to write:

a xor b

instead of defining a function xor(a, b).

Unfortunately, outside of boolean algebra and simulating electrical 
circuits, I can't think of any use-cases for an xor operator. Do you have 
any?



-- 
Steven


From pdpinheiro at gmail.com  Wed Jul 15 05:17:09 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Wed, 15 Jul 2009 02:17:09 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<mailman.3119.1247612922.8015.python-list@python.org>
Message-ID: <522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>

On Jul 15, 12:08?am, Christian Heimes <li... at cheimes.de> wrote:
> Chris Rebert wrote:
> > Using the xor bitwise operator is also an option:
> > bool(x) ^ bool(y)
>
> I prefer something like:
>
> ? ? bool(a) + bool(b) == 1
>
> It works even for multiple tests (super xor):
>
> ? if bool(a) + bool(b) + bool(c) + bool(d) != 1:
> ? ? ? raise ValueError("Exactly one of a, b, c and d must be true")
>
> Christian

"if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
1 = 0 xor 1 = 1 if you assicate to the left)


From bearophileHUGS at lycos.com  Wed Jul 15 05:25:20 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Wed, 15 Jul 2009 02:25:20 -0700 (PDT)
Subject: A question of style .....
References: <430dc862-7c94-4616-a66c-5ed2c033442f@n11g2000yqb.googlegroups.com>
Message-ID: <07945ef8-769d-4ca5-8142-0112a3a7befc@k6g2000yqn.googlegroups.com>

tuxagb:
> If I have to write an extension module with many objects, how can I
> organizing the code?
> I think: every object in a separate file, and a last file with the
> PyInit_..... function. But is unmenageable .....
>
> Solutions?

What do you think about using Cython?

Bye,
bearophile


From tim.wintle at teamrubber.com  Wed Jul 15 05:28:34 2009
From: tim.wintle at teamrubber.com (Tim Wintle)
Date: Wed, 15 Jul 2009 10:28:34 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <4c01f2c4-314d-4690-8904-d19dec9f6241@k1g2000yqf.googlegroups.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3122.1247615131.8015.python-list@python.org>
	<4c01f2c4-314d-4690-8904-d19dec9f6241@k1g2000yqf.googlegroups.com>
Message-ID: <1247650114.7759.13.camel@tim-laptop>


On Wed, 2009-07-15 at 02:02 -0700, Jonathan Gardner wrote:
> On Jul 14, 4:48 pm, Ethan Furman <et... at stoneleaf.us> wrote:
> >
> > A whole family of supers.  :)
> >
>  All the things binary operators can do, Lisp
> does with 0, 1, 2, or more arguments.

+1

n-ary operators are great, but binary operators are just syntactic sugar
for functions (which are obviously a generalisation of an n-ary operator
in python).

The fact that lisp-like languages don't expose this sugar is good for
making you think about what you're actually doing, but just like
mathematicians use binary (and unary) operators in equations rather than
working in the lambda calculus, having that sugar is useful to python.

> 
> [1]> (+)
> 0
> [2]> (+ 1)
> 1
> [3]> (+ 1 2)
> 3
> [4]> (+ 1 2 3)
> 6

c.f. :

>>> sum([])
0
>>> sum([1])
1
>>> sum([1,2])
3
>>> sum([1,2,3])
6



> Once you get used to that, binary operators don't seem so useful
> anymore.
> 
> The equivalent in Python is dropping the operators and replacing them
> with built-in functions that take 0, 1, 2, or more arguments.



From mail at timgolden.me.uk  Wed Jul 15 05:32:55 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 15 Jul 2009 10:32:55 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A5DA247.3040606@timgolden.me.uk>

Steven D'Aprano wrote:
> On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
> 
>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>> to have an 'xor' operator as well.
> 
> I've often wished there was too, for the sake of completeness and 
> aesthetics, I'd love to be able to write:
> 
> a xor b
> 
> instead of defining a function xor(a, b).
> 
> Unfortunately, outside of boolean algebra and simulating electrical 
> circuits, I can't think of any use-cases for an xor operator. Do you have 
> any?

I was pondering on this yesterday, and the only case I've
come across in my code -- and it's reasonably common --
is checking that one and only one of two params has been
passed. I have code which wants, say, an id or a name
but doesn't want both. It's hardly difficult to write the
check even now, but an built-in xor would make it fractionally
cleaner.

TJG



From jarausch at igpm.rwth-aachen.de  Wed Jul 15 05:53:28 2009
From: jarausch at igpm.rwth-aachen.de (Helmut Jarausch)
Date: Wed, 15 Jul 2009 11:53:28 +0200
Subject: convert Dbase (.dbf) files to SQLite databases
Message-ID: <7c5n8kF25pc8bU1@mid.dfncis.de>

Hi,

I have a lot of old Dbase files (.dbf) and I'll like to convert these
to SQLite databases as automatically as possible.
Does anybody know a tool/Python script to do so?

I know, I could use dbfpy and create the SQLite table and import all
data. But is there something easier?

Many thanks for a hint,

Helmut.

-- 
Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany


From hartley79 at gmail.com  Wed Jul 15 05:54:52 2009
From: hartley79 at gmail.com (hartley)
Date: Wed, 15 Jul 2009 02:54:52 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com>
Message-ID: <768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com>

On Jul 14, 2:21?pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 14, 7:22?pm, hartley <hartle... at gmail.com> wrote:> > > I'm very new at wrapping Python/C, and I have run into some problems.
>
> [snip]
>
>
>
> > > > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > > > pValue is now a PyList - i've even verified this with:
>
> > > > int a = PyList_Check(pValue);
> > > > ? ? ? ? printf("%d\n", a);
>
> > > > However, I want to send this PyList to another python module,
>
> > > Please explain "send" ... do you mean the C equivalent of the Python
> > > statement C_embedding.buff = the_pylist ?
>
> > > BTW C-embedding would trigger a syntax error in Python source; best to
> > > avoid ...
>
> > I'm sorry I'm not using the proper terms when trying to describe this
> > - i've never really learnt those terms, I guess i should do that one
> > day.
>
> Today would be a good day to start :-)
>
>
>
>
>
> > Imagine that the python function C-embedding.buff looks like this:
>
> > def buff(a):
> > ? ? if isinstance(a,list):
> > ? ? ? ? print "success"
>
> > I want to send, pass, call, whatever a list argument from the C code
> > onto this function. As simple as this - how can you call a function in
> > python from C, and providing a python list as an argument?
>
> > As I wrote earlier - I already have a PyList, called pValue. But I
> > have not been able to use this as an argument for C-embedding.buff
> > using the code I described last time.
>
> > > > but I
> > > > don't know how to do this. Initially I though I could just do like
> > > > above, only swapping NULL with pValue, but that is not working.
>
> > > > pName2 = PyString_FromString("C-embedding");
> > > > pModule2 = PyImport_Import(pName2);
> > > > pFunc2 = PyObject_GetAttrString(pModule2,"buff");
> > > ?Any good reason for not checking the
> > > return value for an error? [Rhetorical question; answer == "No"]
>
> > > > pValue2 = PyObject_CallObject(pFunc2,pValue);
>
> Your problem is here, in the second arg of PyObject_CallObject. It
> should be either NULL if no args are being supplied, or a tuple
> containing the args if 1 or more args are being supplied. pValue is
> the arg itself; you need to wrap it in a tuple.
>
> Seehttp://docs.python.org/c-api/object.html#PyObject_CallObject
>
> Actually you might like to use this instead (no tuple hassles):
>
> http://docs.python.org/c-api/object.html#PyObject_CallFunctionObjArgs
>
> What are you using as a source of information? Have you read this:
>
> http://docs.python.org/extending/embedding.html#pure-embedding?
>
> It contains a very thorough example of calling a Python function from
> C, with all the reference-counting and error-checking stuff and it's
> quite runnable -- I've just now compiled it and run it (1) as-is (2)
> changed to pass a list instead of multiple ints (3) changed again to
> emulate you trying to pass the list directly instead of wrapped in a
> tuple ... here's the result:
>
> TypeError: argument list must be a tuple
> Call failed
>
> Oh by the way, you can get away with C-embedding as a module name if
> you are importing it from C, but importing it from Python [so that you
> could test it independently of your C program] presents a difficulty
> (syntax error) ... better to change it to c_embedding.
>
> > > It's mainly just a matter of (1) knowing what you want to do (2)
> > > picking the API that does what you want (3) checking the returned
> > > value for error after every call.
>
> HTH,
> John

Thank you, that works! You're a genius :)

As for what I'm reading, I'm familiar with both


http://docs.python.org/c-api/
and
http://docs.python.org/extending/embedding.html#pure-embedding

but i still find it hard to read this and find the proper API. The
Python/C API reference is 162 pages!

I have a second issue that I've also struggled with, namely using
class object (don't shoot me if my terminology is off again). With the
little toy class below, i want to instansiate it, boost it, and return
it, similar to:

s = ObjectTest()
s.boostList()
return s.dispList()

but in C, of course.

so far I have:

pName = PyString_FromString("ob-test");
pModule = PyImport_Import(pName);
pFunc = PyObject_GetAttrString(pModule,"ObjectTest");
if (pFunc && PyCallable_Check(pFunc)) {

            printf("Callable\n");
		}
pObj = PyObject_CallObject(pFunc,NULL);
	if (pObj != NULL) {
	printf("WAS NOT NULL!\n");
}

At least this seems to work. However, as to how to actually
instantiate and use this class the way I described, I have no idea
which API to use. Even though I've spent lots of time reading it! Do
you have any clue here, as well?



(ob-test.py)
class ObjectTest:

	def __init__(self):
		self.list = []


	def boostList(self):
		self.list.append(1)

	def dispList(self):
		return self.list



From quentel.pierre at wanadoo.fr  Wed Jul 15 06:04:01 2009
From: quentel.pierre at wanadoo.fr (Pierre Quentel)
Date: Wed, 15 Jul 2009 03:04:01 -0700 (PDT)
Subject: select lines in python
References: <mailman.3100.1247592844.8015.python-list@python.org>
Message-ID: <f828ddb0-7370-4992-bd6e-fd3bdd07e393@c1g2000yqi.googlegroups.com>

On 14 juil, 19:33, amr... at iisermohali.ac.in wrote:
> Dear all,
>
> Can anyone tell me that suppose i have a file having content like:
>
> ? ? _Atom_name
> ? ? ? _Atom_type
> ? ? ? _Chem_shift_value
> ? ? ? _Chem_shift_value_error
> ? ? ? _Chem_shift_ambiguity_code
> ? ? ?1 ? ? 1 ? PHE ? ? ? H ? ? H ? ? ?8.49 ? ? 0.02 ? ? 1
> ? ? ?2 ? ? 1 ? PHE ? ? ? HA ? ?H ? ? ?4.60 ? ? 0.02 ? ? 1
> ? ? ?3 ? ? 1 ? PHE ? ? ? CA ? ?C ? ? 57.83 ? ? ?0.3 ? ? 1
> ? ? ?4 ? ? 2 ? LEU ? ? ? H ? ? H ? ? ?8.23 ? ? 0.02 ? ? 1
> ? ? ?5 ? ? 2 ? LEU ? ? ? HA ? ?H ? ? ?4.25 ? ? 0.02 ? ? 1
> ? ? ?6 ? ? 2 ? LEU ? ? ? HB2 ? H ? ? ?1.54 ? ? 0.02 ? ? 1
> ? ? ?7 ? ? 3 ? ASP ? ? ? H ? ? H ? ? ?8.10 ? ? 0.02 ? ? 1
> ? ? ?8 ? ? 3 ? ASP ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
> ? ? ?9 ? ? 3 ? ASP ? ? ? HB2 ? H ? ? ?2.65 ? ? 0.02 ? ? 1
> stop
>
> now what i want that instead of copying all the lines it will just write
> the information about PHE and ASP then how i acn do that using python
> programming.Kindly tell me the command for that.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA

Hi,

The problem here is to test the values at specific colums in the file.
So I'd rather split each line into a list of values and do a test on
relevant items, like :

for line in open(filename):
    items = line.strip().split()
    if items[1] in ["ASP","PHE"]:
        (... handle this case ...)

Using re here is probably not the best way. It may happen that a
sequence appearing in a column also appears in another one ; and when
the tests become more complex the regular expression itself might
become complex, or even impossible (imagine the OP wants to test that
the numeric values are below a certain threshold)

- Pierre


From ben+python at benfinney.id.au  Wed Jul 15 06:08:13 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Wed, 15 Jul 2009 20:08:13 +1000
Subject: Teaching pylint about keyword placeholders in string formatting
Message-ID: <87bpnmjm2a.fsf@benfinney.id.au>

Howdy all,

A common idiom I use is::

    def frobnicate(warble):
        foo = complex_computation()
        bar = long.access.path.leading.to.useful.value
        baz = (lengthy + expression * with_several_parts)
        spangulate("%(warble)s: %(foo)s%(bar)s [%(baz)d]" % vars())

This allows the format of the string to be clear, and allows the
separate parts of it to have meaningful names.

However, this is causing pylint to complain::

    W:218:frobnicate: Unused argument 'warble'
    W:219:frobnicate: Unused variable 'foo'
    W:220:frobnicate: Unused variable 'bar'
    W:221:frobnicate: Unused variable 'baz'

That is, pylint is not aware that the names used by accessing the values
from the dictionary returned by ?vars()?.

This warning, when it actually *does* detect unused name bindings, is
very useful; I don't want to disable it. Nor do I want to pepper my code
with hints to pylint about each one of these, detracting significantly
from the readability which is the main point of the above idiom.

How can I make pylint aware in the general case that the above idiom
does, in fact, constitute a use of the names ?warble?, ?foo?, ?bar?, and
?baz? in the code?

-- 
 \         ?Pinky, are you pondering what I'm pondering?? ?I think so, |
  `\    Brain, but if we give peas a chance, won't the lima beans feel |
_o__)                                left out?? ?_Pinky and The Brain_ |
Ben Finney



From david.lyon at preisshare.net  Wed Jul 15 06:39:21 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Wed, 15 Jul 2009 06:39:21 -0400
Subject: convert Dbase (.dbf) files to SQLite databases
In-Reply-To: <7c5n8kF25pc8bU1@mid.dfncis.de>
References: <7c5n8kF25pc8bU1@mid.dfncis.de>
Message-ID: <942d96482771b3b7a0e4294381c5f3dd@preisshare.net>

On Wed, 15 Jul 2009 11:53:28 +0200, Helmut Jarausch
<jarausch at igpm.rwth-aachen.de> wrote:
> Hi,
> 
> I have a lot of old Dbase files (.dbf) and I'll like to convert these
> to SQLite databases as automatically as possible.
> Does anybody know a tool/Python script to do so?
> 
> I know, I could use dbfpy and create the SQLite table and import all
> data. But is there something easier?

yes...

Use OpenOffice-Scalc or MS-Office-Excel to open the table...

Export to csv....

Use SQLite Manager (https://addons.mozilla.org/en-US/firefox/addon/5817)

and use the import wizard to import your data....

It shouldn't take too long...

David


From piet at cs.uu.nl  Wed Jul 15 06:39:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 12:39:26 +0200
Subject: promlems with threading and print
References: <mailman.3139.1247646986.8015.python-list@python.org>
Message-ID: <m2k52axmap.fsf@cs.uu.nl>

>>>>> Andreas Grommek <andi at mozarellasalat.homelinux.net> (AG) wrote:

>AG> Hi Newsgroup,
>AG> I'm new to python and I am familiarizing myself with threads
>AG> (haven't done any threading in any other language before...). I was
>AG> playing around and discovered some weird behavior. Here is my code:

When you start programming with threads you should familiarize yourself
with (or better: study) the subject of parallel programming. Without
that you will make hard to find and debug errors. Fortunately this one
you did find. Many of these have to do with 'shared resources', i.e.
resources (like objects) that are used in more than one thread at the
same time, while at least one thread modifies it/them.

For a start read this: http://effbot.org/zone/thread-synchronization.htm
and then read some more elaborate literature.

>AG> import threading
>AG> from time import sleep
>AG> from random import random
>AG> import sys

>AG> class MyThread(threading.Thread):

>AG>     def __init__(self, t, s):
>AG>         self.threadmarker = t
>AG>         self.sleeptime = s
>AG>         threading.Thread.__init__(self)

>AG>     def run(self):
>AG>         print("Tread", self.threadmarker, "is going to sleep for a while...")
>AG>         sys.stdout.flush()     #flush I/O
>AG>         sleep(self.sleeptime)  #go to sleep
>AG>         print("Tread", self.threadmarker, "is waking up and terminating")

What happens here is that stdout is a shared resource that you are
modifying in different threads. So you have to protect it.

>AG> a = 1
>AG> b = 20
>AG> for n in range(a, b):
>AG>    x = MyThread(n,random()*10.0)
>AG>    x.start()


>AG> This should create some threads which print messages, go to sleep for a random amount of time (max
>AG> 10 seconds) and return with a message. When I run the code I get something like this (always different):

You can get even weirder stuff, like:

('Tread', 1, 'is going to sleep for a while...')
('Tread', 2, 'is going to sleep for a while...')
('Tread', 3, 'is going to sleep for a while...')
('Tread', 4, 'is going to sleep for a while...')
('Tread', 5, 'is going to sleep for a while...')
('Tread', 6, 'is going to sleep for a while...')
('Tread', 7, 'is going to sleep for a while...')
('Tread', 8('Tread', , 'is going to sleep for a while...'9, )'is going to sleep for a while...'
 ('Tread'), 
10, 'is going to sleep for a while...')
('Tread'('Tread', 12, 'is going to sleep for a while...')
, 11, 'is going to sleep for a while...')
('Tread', 13, 'is going to sleep for a while...')
('Tread', 14, 'is going to sleep for a while...')
('Tread', 15, 'is going to sleep for a while...')
('Tread', 16, 'is going to sleep for a while...')
('Tread', 17, 'is going to sleep for a while...')
('Tread'('Tread', 19, 'is going to sleep for a while...')
, 18, 'is going to sleep for a while...')
('Tread', 10, 'is waking up and terminating')
...

Here is a solution using locks (and at the same time I corrected
Tread->Thread

class MyThread(threading.Thread):

    def __init__(self, t, s, lock):
        self.lock = lock
        self.threadmarker = t
        self.sleeptime = s
        threading.Thread.__init__(self)

    def run(self):
        with lock:
            print("Thread", self.threadmarker, "is going to sleep for a while...")
            sys.stdout.flush()     #flush I/O
        sleep(self.sleeptime)  #go to sleep
        with lock:
            print("Thread", self.threadmarker, "is waking up and terminating")

a = 1
b = 20
lock = threading.Lock()
for n in range(a, b):
   x = MyThread(n,random()*10.0, lock)
   x.start()

If you have an older version of Python you have to replace
        with lock:
            statement
by
        lock.acquire()
        try:
            statement
        finally:
            lock.release()

or if you want to risk deadlocks:

        lock.acquire()
        statement
        lock.release()

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nicolas.chauvat at logilab.fr  Wed Jul 15 06:39:48 2009
From: nicolas.chauvat at logilab.fr (Nicolas Chauvat)
Date: Wed, 15 Jul 2009 12:39:48 +0200
Subject: [TIP] Teaching pylint about keyword placeholders in string
	formatting
In-Reply-To: <87bpnmjm2a.fsf@benfinney.id.au>
References: <87bpnmjm2a.fsf@benfinney.id.au>
Message-ID: <20090715103948.GA6248@volans.logilab.fr>

Hi,

On Wed, Jul 15, 2009 at 08:08:13PM +1000, Ben Finney wrote:
>     def frobnicate(warble):
>         foo = complex_computation()
>         bar = long.access.path.leading.to.useful.value
>         baz = (lengthy + expression * with_several_parts)
>         spangulate("%(warble)s: %(foo)s%(bar)s [%(baz)d]" % vars())
> 
> This allows the format of the string to be clear, and allows the
> separate parts of it to have meaningful names.
> 
> However, this is causing pylint to complain::
> ...
> That is, pylint is not aware that the names used by accessing the values
> from the dictionary returned by ?vars()?.
> ...

You are not the only one:
http://lists.logilab.org/pipermail/python-projects/2009-July/thread.html

Here is the ticket:
https://www.logilab.net/elo/ticket/9634

Thanks for the report. As usual, help and patches are welcome.

-- 
Nicolas Chauvat

logilab.fr - services en informatique scientifique et gestion de connaissances  


From denis-bz-gg at t-online.de  Wed Jul 15 06:46:23 2009
From: denis-bz-gg at t-online.de (denis)
Date: Wed, 15 Jul 2009 03:46:23 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com> 
	<mailman.3073.1247547957.8015.python-list@python.org>
Message-ID: <22fa2fe9-899b-407a-8e3c-49f29c86fa59@r33g2000yqn.googlegroups.com>

Sure, Aho-Corasick is fast for fixed strings; but without real
numbers / a concrete goal
> > Matt, how many words are you looking for, in how long a string ?

a simple solution is good enough, satisficing.  Matt asked "how to
make that function look nicer?"
but "nice" has many dimensions -- bicycles are nice for some tasks,
Ferraris for others.

Bytheway http://en.wikipedia.org/wiki/Aho-Corasick_algorithm has a
link to a Python implementation,
also http://en.wikipedia.org/wiki/Worse_is_Better is fun.



From fabiodib at email.it  Wed Jul 15 06:49:11 2009
From: fabiodib at email.it (fdb)
Date: Wed, 15 Jul 2009 12:49:11 +0200
Subject: dictionary inherit and method overriding
Message-ID: <h3kc78$goq$1@ger.gmane.org>

Hi all,

I need to extend and not replace the __getitem__ method of a dict class.

Here is sample the code:

>>> class myDict(dict):
...     def __getitem__(self, y):
...         print("Doing something")
...         dict.__getitem__(self, y)
...
>>> a=myDict()
>>> a["value"] = 1
>>> print a["value"]
None

As you see i get None instead of  1.

Any solutions?

Bye

-- 
FabioBD



From digitig at gmail.com  Wed Jul 15 06:54:06 2009
From: digitig at gmail.com (Tim Rowe)
Date: Wed, 15 Jul 2009 11:54:06 +0100
Subject: Calling functions: Why this complicated ?
In-Reply-To: <12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
	<89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
	<12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>
Message-ID: <aee48b3c0907150354v4d51004p55f300c690af0308@mail.gmail.com>

2009/7/15 Jeremiah Dodds <jeremiah.dodds at gmail.com>:

> As a hopefully semi-informative aside, I've been writing python code for a
> few years now, and I regularly use all four forms of argument passing listed
> above.

Curiously, I never use the all-named style in Python, whereas it's my
normal style in Ada. I shall now enter a period of self-refelection to
try to work out why I am so inconsistent :-)


-- 
Tim Rowe


From ben+python at benfinney.id.au  Wed Jul 15 07:01:07 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Wed, 15 Jul 2009 21:01:07 +1000
Subject: Teaching pylint about keyword placeholders in string	formatting
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
Message-ID: <877hyajjm4.fsf@benfinney.id.au>

Nicolas Chauvat <nicolas.chauvat at logilab.fr> writes:

> On Wed, Jul 15, 2009 at 08:08:13PM +1000, Ben Finney wrote:
> > That is, pylint is not aware that the names used by accessing the values
> > from the dictionary returned by ?vars()?.
> > ...
> 
> You are not the only one:
> http://lists.logilab.org/pipermail/python-projects/2009-July/thread.html

Thank you.

I think the thread Nicolas wanted me to see was this one:
<URL:http://lists.logilab.org/pipermail/python-projects/2009-July/001950.html>.

-- 
 \             ?I put contact lenses in my dog's eyes. They had little |
  `\   pictures of cats on them. Then I took one out and he ran around |
_o__)                                      in circles.? ?Steven Wright |
Ben Finney



From nicolas.chauvat at logilab.fr  Wed Jul 15 07:21:26 2009
From: nicolas.chauvat at logilab.fr (Nicolas Chauvat)
Date: Wed, 15 Jul 2009 13:21:26 +0200
Subject: [Python-projects] [TIP] Teaching pylint about keyword
	placeholders in string formatting
In-Reply-To: <20090715103948.GA6248@volans.logilab.fr>
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
Message-ID: <20090715112126.GA7138@volans.logilab.fr>

On Wed, Jul 15, 2009 at 12:39:48PM +0200, Nicolas Chauvat wrote:
> Here is the ticket:
> https://www.logilab.net/elo/ticket/9634

Apologies: http://www.logilab.org/ticket/9634

-- 
Nicolas Chauvat

logilab.fr - services en informatique scientifique et gestion de connaissances  


From lists at cheimes.de  Wed Jul 15 07:31:44 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 15 Jul 2009 13:31:44 +0200
Subject: dictionary inherit and method overriding
In-Reply-To: <h3kc78$goq$1@ger.gmane.org>
References: <h3kc78$goq$1@ger.gmane.org>
Message-ID: <h3ken0$qm6$1@ger.gmane.org>

fdb wrote:
> Hi all,
> 
> I need to extend and not replace the __getitem__ method of a dict class.
> 
> Here is sample the code:
> 
>>>> class myDict(dict):
> ....     def __getitem__(self, y):
> ....         print("Doing something")
> ....         dict.__getitem__(self, y)
> ....
>>>> a=myDict()
>>>> a["value"] = 1
>>>> print a["value"]
> None
> 
> As you see i get None instead of  1.
> 
> Any solutions?

How about returning the value? :]

Christian



From lists at cheimes.de  Wed Jul 15 07:37:22 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 15 Jul 2009 13:37:22 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<mailman.3119.1247612922.8015.python-list@python.org>
	<522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
Message-ID: <h3kf1i$rle$1@ger.gmane.org>

pdpi wrote:
> On Jul 15, 12:08 am, Christian Heimes <li... at cheimes.de> wrote:
>> Chris Rebert wrote:
>>> Using the xor bitwise operator is also an option:
>>> bool(x) ^ bool(y)
>> I prefer something like:
>>
>>     bool(a) + bool(b) == 1
>>
>> It works even for multiple tests (super xor):
>>
>>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>>       raise ValueError("Exactly one of a, b, c and d must be true")
>>
>> Christian
> 
> "if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
> xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
> 1 = 0 xor 1 = 1 if you assicate to the left)

I'm well aware of the fact that I've described something differently.
'xor' can be explained as 'check if exactly one element of two elements
is true'. My algorithms describes a super xor, aka 'check if exactly one
element of n elements is true'.

Christian



From dzizes451 at gmail.com  Wed Jul 15 08:07:20 2009
From: dzizes451 at gmail.com (dzizes)
Date: Wed, 15 Jul 2009 05:07:20 -0700 (PDT)
Subject: how to set timeout while colling a soap method?
In-Reply-To: <e26bf425-f06a-49c3-8ad2-e52e82f3b080@r34g2000vba.googlegroups.com>
References: <24461403.post@talk.nabble.com>
	<e26bf425-f06a-49c3-8ad2-e52e82f3b080@r34g2000vba.googlegroups.com>
Message-ID: <24496577.post@talk.nabble.com>


Yes, that is what I was looking for.

Greets!!

-- 
View this message in context: http://www.nabble.com/how-to-set-timeout-while-colling-a-soap-method--tp24461403p24496577.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From lawson89 at gmail.com  Wed Jul 15 08:09:54 2009
From: lawson89 at gmail.com (Rick Lawson)
Date: Wed, 15 Jul 2009 05:09:54 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
Message-ID: <12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>

On Jul 15, 4:53?am, Jonathan Gardner <jgard... at jonathangardner.net>
wrote:
> On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
>
> > Appreciate any help on this. I am porting an app from Java to python
> > and need generic object pooling with hooks for object initialization /
> > cleanup and be able to specify an object timeout.
>
> Are you looking for something like a thread pool or a connection pool?
> Such a thing is easy to code in Python. Might as well write one from
> scratch for your particular need.
>
> By the way, a tip for writing Python: Forget Java. If you're porting
> an app, consider rewriting it from the architecture on up. You'll save
> yourself time and get a better result.

Jonathan,

Thanks for the advice but would like to pick your brain a little more.
The pool I need is not a thread pool or db pool. I need to pool
objects which are a proxy for an external C process that communicates
via sockets. The pool is necessary because the initial connection/
authentication is expensive, plus the connection needs to be recycled
every so often due to instability on the C side. The existing Java
code uses commons-pool which incidentally is the base object pool for
a db connection pooling library (DBCP). Anyway, maybe this is just so
easy to do in Python that everyone rolls their own - but I have done a
lot of googling with no luck.

I just hate to re-invent the wheel here - I guess I should look at a
db connection pooling library and see if they have a generic object
pool somewhere in there. Any you can recommend that are more or less
standalone db connection pool libraries ?

Thanks,
Rick


From sorry.no at can.do  Wed Jul 15 08:15:53 2009
From: sorry.no at can.do (Borivoj)
Date: Wed, 15 Jul 2009 14:15:53 +0200
Subject: Need help with oo design while using TreeWidget
Message-ID: <h3kha0$8m3$1@ss408.t-com.hr>

I'm looking for objective oriented and pythonic way to solve my problem.

I'm using IDLE's TreeWidget, by inheriting TreeItem and overriding some of 
it's methods. My tree structure is defined inside treedata, which is 
xml.dom.minidom object. MenuTreeFrame is responsible for displaying the 
widget inside it's own Frame. As you can see in the source, MyTreeItem is 
one child in tree, and it's method GetSubList is responsible for creating 
it's children TreeItems.

When creating each child, I have to pass original tree structure (treedata) 
to each child. Once I implement event firing, I will have to pass Event 
reference to each child as well. There has to be a better way to make these 
references available to each child in tree. What would you recommend?

My code looks something like this (not executable, because treedata 
definition is lacking):

import Tkinter as tk
from TreeWidget import TreeItem, TreeNode, ScrolledCanvas

class MenuTreeFrame(tk.Frame):
    def __init__(self, parent, treedata):
        tk.Frame.__init__(self, parent)
        self.treedata = treedata
        sc = ScrolledCanvas(self, bg='white', width=150, 
highlightthickness=0, takefocus=1)
        self.canvas = sc.canvas
        sc.frame.pack(fill="both", expand=1)
    def update(self, dom):
        self.create(dom) # TODO: implement something smarter than recreating 
whole tree
    def create(self, dom):
        self.rootitem = DomTreeItem(dom.documentElement, self.treedata)
        self.node = TreeNode(self.canvas, None, self.rootitem)
        self.node.update()
        self.node.select()
        self.rootitem.OnSelect()
        self.node.expand()

class MyTreeItem(TreeItem):
    def __init__(self, treenode, treedata):
        self.node = treenode
        self.previously_selected = None
        self.treedata = treedata
    def GetText(self):
        return self.node.firstChild.nodeValue
    def IsExpandable(self):
        node = self.node
        return len(self.node.getElementsByTagName('node')) > 0
    def OnSelect(self):
        self.treedata.current = self.node
        # TODO: fire off the event
    def GetSubList(self):
        parent = self.node
        children = parent.childNodes
        itemlist = [MyTreeItem(node, self.treedata) for node in children if 
node.nodeName == 'node']
        return itemlist


Thanks for reading
Josip 




From fabiodib at email.it  Wed Jul 15 08:19:15 2009
From: fabiodib at email.it (fdb)
Date: Wed, 15 Jul 2009 14:19:15 +0200
Subject: dictionary inherit and method overriding
In-Reply-To: <h3ken0$qm6$1@ger.gmane.org>
References: <h3kc78$goq$1@ger.gmane.org> <h3ken0$qm6$1@ger.gmane.org>
Message-ID: <h3khg7$3ju$1@ger.gmane.org>

Only this! I'm going crazy!

Than you!

Code:


class myDict(dict):
    def __getitem__(self, y):
        print("Doing something")
        return dict.__getitem__(self, y)

a=myDict()
a["value"] = 1
print a["value"]


Christian Heimes ha scritto:
> How about returning the value? :]


-- 
FabioBD



From sjmachin at lexicon.net  Wed Jul 15 08:34:31 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 15 Jul 2009 05:34:31 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com>
Message-ID: <802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>

On Jul 15, 7:54?pm, hartley <hartle... at gmail.com> wrote:
> On Jul 14, 2:21?pm, John Machin <sjmac... at lexicon.net> wrote:
> > On Jul 14, 7:22?pm, hartley <hartle... at gmail.com> wrote:> > > I'm very new at wrapping Python/C, and I have run into some problems.

[snip]

/* the first telling */
> > > > statement C_embedding.buff = the_pylist ?
>
> > > > BTW C-embedding would trigger a syntax error in Python source; best to
> > > > avoid ...

/* the second telling */
> > Oh by the way, you can get away with C-embedding as a module name if
> > you are importing it from C, but importing it from Python [so that you
> > could test it independently of your C program] presents a difficulty
> > (syntax error) ... better to change it to c_embedding.
>
>
> As for what I'm reading, I'm familiar with both
>
> http://docs.python.org/c-api/
> andhttp://docs.python.org/extending/embedding.html#pure-embedding

You must have a very strange definition of familiarity! That section
has as I pointed out a complete working example of a C program that
calls a Python function with 1 or more arguments, complete with error
checking and reference counting. To me, familiarity would include
reading that program, understanding what it is doing (there are
copious explanations), compiling it, running it, then start making
changes (like I did) to do things like what you want to do.

> but i still find it hard to read this and find the proper API. The
> Python/C API reference is 162 pages!

It's a reference, not a novel. You needed no API that was not in the
sample program. What you should do is when you are going through the
example programs, look up each API in the reference manual to see what
the arguments are supposed to be, what other possibilities there are
(e.g. PyObject_CallObject 2nd arg is NULL or a tuple of your args),
what the return value is, what if anything is said about reference
counts, what similar APIs are there (e.g. a few called
PyObject_Callxxxxxxx)

> I have a second issue that I've also struggled with, namely using
> class object (don't shoot me if my terminology is off again). With the
> little toy class below, i want to instansiate it, boost it, and return
> it, similar to:
>
> s = ObjectTest()
> s.boostList()
> return s.dispList()

Let's break that down:

alist = s.dispList()
return alist

s.dispList (despite its name indicating "display") returns a reference
to a list. Your C program is going to return that to whom? The shell?

> but in C, of course.
>
> so far I have:
>
> pName = PyString_FromString("ob-test");

/* the third telling */
s/-/_/

"What I tell you three times is true". Just do it.

> pModule = PyImport_Import(pName);

You've imported the module. So far, I'm making the charitable
assumption that the lack of error checking is for brevity in your
posting, but is there in your actual code.

> pFunc = PyObject_GetAttrString(pModule,"ObjectTest");

You've obtained a reference to the class.

> if (pFunc && PyCallable_Check(pFunc)) {
>
> ? ? ? ? ? ? printf("Callable\n");
> ? ? ? ? ? ? ? ? }

And if there's a problem, you'll fall through and use the dud
reference to the class??

Get into the habit NOW of doing the error checking properly, after
each API call; otherwise debugging will become a nightmare. Follow the
examples in the sample program. In this case, it is necessary only to
test for NULL, and get the correct error message displayed for that.
Checking if the returned object is callable in the same if-test clouds
the issue. Checking for callability separately is quite unnecessary --
just call the object and you'll find out then if it's not callable.

> pObj = PyObject_CallObject(pFunc,NULL);
> ? ? ? ? if (pObj != NULL) {
> ? ? ? ? printf("WAS NOT NULL!\n");

Again instead of printing congratulatory messages on success, put in
proper checking for failure, get the error message printed and bale
out.

> }
>
> At least this seems to work. However, as to how to actually
> instantiate and use this class the way I described, I have no idea
> which API to use.

You don't know how to instantiate the class? What do you think was the
purpose of the PyObject_CallObject() that you just did??

> Even though I've spent lots of time reading it! Do
> you have any clue here, as well?

Let's trawl through the Python equivalent of what you want to do:

s = amodule.ObjectTest()
(1) import the module
(2) get the "objectTest" attribute of the module
(3) call it, park the result in s

s.boostList()
(1) get the "boostList" attribute of s
(2) call it ... but it's a method, maybe we need to use a different
PyObject_Callxxxxxx ... no result to park.

x = s.dispList()
(1) get the "displist" attribute of s
(2) call it (see above), park result in x
(3) do something sensible with x

>
> (ob-test.py)
> class ObjectTest:
>
> ? ? ? ? def __init__(self):
> ? ? ? ? ? ? ? ? self.list = []
>
> ? ? ? ? def boostList(self):
> ? ? ? ? ? ? ? ? self.list.append(1)
>
> ? ? ? ? def dispList(self):
> ? ? ? ? ? ? ? ? return self.list

HTH,
John


From deets at nospam.web.de  Wed Jul 15 08:40:05 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 14:40:05 +0200
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
Message-ID: <7c60ooF25j7lsU1@mid.uni-berlin.de>

Rick Lawson wrote:

> On Jul 15, 4:53?am, Jonathan Gardner <jgard... at jonathangardner.net>
> wrote:
>> On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
>>
>> > Appreciate any help on this. I am porting an app from Java to python
>> > and need generic object pooling with hooks for object initialization /
>> > cleanup and be able to specify an object timeout.
>>
>> Are you looking for something like a thread pool or a connection pool?
>> Such a thing is easy to code in Python. Might as well write one from
>> scratch for your particular need.
>>
>> By the way, a tip for writing Python: Forget Java. If you're porting
>> an app, consider rewriting it from the architecture on up. You'll save
>> yourself time and get a better result.
> 
> Jonathan,
> 
> Thanks for the advice but would like to pick your brain a little more.
> The pool I need is not a thread pool or db pool. I need to pool
> objects which are a proxy for an external C process that communicates
> via sockets. The pool is necessary because the initial connection/
> authentication is expensive, plus the connection needs to be recycled
> every so often due to instability on the C side. The existing Java
> code uses commons-pool which incidentally is the base object pool for
> a db connection pooling library (DBCP). Anyway, maybe this is just so
> easy to do in Python that everyone rolls their own - but I have done a
> lot of googling with no luck.
> 
> I just hate to re-invent the wheel here - I guess I should look at a
> db connection pooling library and see if they have a generic object
> pool somewhere in there. Any you can recommend that are more or less
> standalone db connection pool libraries ?

I don't know enough about your domain, e.g. if your pooled objects have
state or not.

Assuming that 

 - they are objects
 - they don't have state (like database connections)
 - you want to recycle them after so many calls

one of the simplest solutions would be something like this:

class AutoDestructingWrapper(object):

   MAX_CALL_COUNT = 1000

   def __init__(self, object_factory):
       self._object_factory = object_factory
       self._call_count = self.MAX_CALL_COUNT


   def __getattr__(self, name):
       if self._call_count >= self.MAX_CALL_COUNT:
          self._delegate = self._object_factory()
       return getattr(self._delegate, name)


Diez


From jeremiah.dodds at gmail.com  Wed Jul 15 09:04:12 2009
From: jeremiah.dodds at gmail.com (Jeremiah Dodds)
Date: Wed, 15 Jul 2009 14:04:12 +0100
Subject: Calling functions: Why this complicated ?
In-Reply-To: <aee48b3c0907150354v4d51004p55f300c690af0308@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
	<89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
	<12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>
	<aee48b3c0907150354v4d51004p55f300c690af0308@mail.gmail.com>
Message-ID: <12cbbbfc0907150604k33a6d468l387742ff0aa0a999@mail.gmail.com>

On Wed, Jul 15, 2009 at 11:54 AM, Tim Rowe <digitig at gmail.com> wrote:

>
> Curiously, I never use the all-named style in Python, whereas it's my
> normal style in Ada. I shall now enter a period of self-refelection to
> try to work out why I am so inconsistent :-)
>
>
>
I use it for functions that only (or mostly) have behaviour-modifying flags
and for functions that take more than 3 or so parameters.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090715/af589c36/attachment.html>

From aahz at pythoncraft.com  Wed Jul 15 09:05:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 15 Jul 2009 06:05:30 -0700
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <m27hybyo95.fsf@cs.uu.nl>
	<h3j2hu$nmf$1@panix3.panix.com> <m2vdluxt0j.fsf@cs.uu.nl>
Message-ID: <h3kk6q$qn9$1@panix3.panix.com>

In article <m2vdluxt0j.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>
>>A> In article <m27hybyo95.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>>>> 
>>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>>A> <piet at cs.uu.nl> wrote: 
>>>> 
>>>>>>> And to get c.x = 4 working you also need a __setitem__. 
>>>> 
>>A> Nope.  You do need __setitem__ so that this works:
>>>> 
>>A> c['x'] = 4
>>>> 
>>>> Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
>>>> that was what the OP wanted (I think).
>
>>A> c.x = 4 
>>A> already updates the instance dict, so there's no need to change any class
>>A> methods to support it.  That is, IME it's much better to add methods to
>>A> a regular class to make it more dict-like using the built-in instance
>>A> dict rather than changing any of the attribute mechanisms.  If you're
>>A> really curious, I recommend trying several approaches yourself to see
>>A> what works better.  ;-)
>
>Yes, that's why I mentioned __setitem__. I just mixed up the motivation.

Gotcha.  Unfortunately, I can only respond to what you've written, not
what you intended to write.  ;-)  (There was enough misinformation
earlier in this thread that I felt being really really clear was
important.)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From pdpinheiro at gmail.com  Wed Jul 15 09:12:03 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Wed, 15 Jul 2009 06:12:03 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<mailman.3119.1247612922.8015.python-list@python.org>
	<522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
	<mailman.3152.1247657854.8015.python-list@python.org>
Message-ID: <a9ae690a-c9db-4563-b42b-c37c6521ef66@c36g2000yqn.googlegroups.com>

On Jul 15, 12:37?pm, Christian Heimes <li... at cheimes.de> wrote:
> pdpi wrote:
> > On Jul 15, 12:08 am, Christian Heimes <li... at cheimes.de> wrote:
> >> Chris Rebert wrote:
> >>> Using the xor bitwise operator is also an option:
> >>> bool(x) ^ bool(y)
> >> I prefer something like:
>
> >> ? ? bool(a) + bool(b) == 1
>
> >> It works even for multiple tests (super xor):
>
> >> ? if bool(a) + bool(b) + bool(c) + bool(d) != 1:
> >> ? ? ? raise ValueError("Exactly one of a, b, c and d must be true")
>
> >> Christian
>
> > "if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
> > xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
> > 1 = 0 xor 1 = 1 if you assicate to the left)
>
> I'm well aware of the fact that I've described something differently.
> 'xor' can be explained as 'check if exactly one element of two elements
> is true'. My algorithms describes a super xor, aka 'check if exactly one
> element of n elements is true'.
>
> Christian

Well, I just wouldn't call it a "super xor" then, when "unicity test"
works much better -- especially as an alternative to an actual xor
without any specification to the actual intended functionality except
the exception text.


From peter.fodrek at stuba.sk  Wed Jul 15 09:12:52 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Wed, 15 Jul 2009 15:12:52 +0200
Subject: import module unbelieveable behaviour
Message-ID: <200907151512.52607.peter.fodrek@stuba.sk>

Dear conference!

I have test Why python based script for HeeksCNC post-processing does not 
work...  And I've got unbelievable behavior  When importing module module 
manually it works, but same opertaion from script does not
 work as seen

/opt/HeeksCAD8/HeeksCNC> python
Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
[GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import nc.rez
>>>
/opt/HeeksCAD8/HeeksCNC> python test.py
Traceback (most recent call last):
  File "test.py", line 7, in <module>
    import nc.rez
ImportError: No module named rez


/opt/HeeksCAD8/HeeksCNC> python ./test.py
Traceback (most recent call last):
  File "./test.py", line 7, in <module>
    import nc.rez
ImportError: No module named rez


Would anyone be helpful for me to get more information about this problem 
because  pydb does not show anything usable for me,please?

I look forward hearing form you

Yours  faithfully

Peter Fodrek


From mail at microcorp.co.za  Wed Jul 15 09:37:30 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 15 Jul 2009 15:37:30 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <002101ca0551$66d1dd40$0d00a8c0@Hendrik>


"Steven D'Aprano" <steven at REMOVE.THIS.cy..e.com.au> wrote:

>Unfortunately, outside of boolean algebra and simulating electrical 
>circuits, I can't think of any use-cases for an xor operator. Do you have 
>any?

A bitwise xor is a poor man's comparator - if the result is binary zero,
the operands were equal, no matter what they represented.

Not much use in python, though.

- Hendrik






From deets at nospam.web.de  Wed Jul 15 09:43:06 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 15:43:06 +0200
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
	<7c60ooF25j7lsU1@mid.uni-berlin.de>
Message-ID: <7c64etF26e7lsU1@mid.uni-berlin.de>

Diez B. Roggisch wrote:

> Rick Lawson wrote:
> 
>> On Jul 15, 4:53?am, Jonathan Gardner <jgard... at jonathangardner.net>
>> wrote:
>>> On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
>>>
>>> > Appreciate any help on this. I am porting an app from Java to python
>>> > and need generic object pooling with hooks for object initialization /
>>> > cleanup and be able to specify an object timeout.
>>>
>>> Are you looking for something like a thread pool or a connection pool?
>>> Such a thing is easy to code in Python. Might as well write one from
>>> scratch for your particular need.
>>>
>>> By the way, a tip for writing Python: Forget Java. If you're porting
>>> an app, consider rewriting it from the architecture on up. You'll save
>>> yourself time and get a better result.
>> 
>> Jonathan,
>> 
>> Thanks for the advice but would like to pick your brain a little more.
>> The pool I need is not a thread pool or db pool. I need to pool
>> objects which are a proxy for an external C process that communicates
>> via sockets. The pool is necessary because the initial connection/
>> authentication is expensive, plus the connection needs to be recycled
>> every so often due to instability on the C side. The existing Java
>> code uses commons-pool which incidentally is the base object pool for
>> a db connection pooling library (DBCP). Anyway, maybe this is just so
>> easy to do in Python that everyone rolls their own - but I have done a
>> lot of googling with no luck.
>> 
>> I just hate to re-invent the wheel here - I guess I should look at a
>> db connection pooling library and see if they have a generic object
>> pool somewhere in there. Any you can recommend that are more or less
>> standalone db connection pool libraries ?
> 
> I don't know enough about your domain, e.g. if your pooled objects have
> state or not.
> 
> Assuming that
> 
>  - they are objects
>  - they don't have state (like database connections)
>  - you want to recycle them after so many calls
> 
> one of the simplest solutions would be something like this:
> 
> class AutoDestructingWrapper(object):
> 
>    MAX_CALL_COUNT = 1000
> 
>    def __init__(self, object_factory):
>        self._object_factory = object_factory
>        self._call_count = self.MAX_CALL_COUNT
> 
> 


This must be 

   def __getattr__(self, name):
       self._call_count += 1
       if self._call_count >= self.MAX_CALL_COUNT:
          self._delegate = self._object_factory()
          self._call_count = 0
       return getattr(self._delegate, name)

of course.

Diez


From python at mrabarnett.plus.com  Wed Jul 15 10:21:27 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 15 Jul 2009 15:21:27 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A5DE5E7.5070003@mrabarnett.plus.com>

Steven D'Aprano wrote:
> On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
> 
>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>> to have an 'xor' operator as well.
> 
> I've often wished there was too, for the sake of completeness and 
> aesthetics, I'd love to be able to write:
> 
> a xor b
> 
> instead of defining a function xor(a, b).
> 
> Unfortunately, outside of boolean algebra and simulating electrical 
> circuits, I can't think of any use-cases for an xor operator. Do you have 
> any?
> 
The problem is that 'and' and 'or' are not limited to Boolean values:

     'and' returns the first false value or the last true value.

     'or' returns the first true value or the last false value.

What values should 'xor' return? IMHO, if only one of the values is true
then it should return that value, otherwise it should return False.

     1 xor 0 => 1
     0 xor 2 => 2
     1 xor 2 => False
     0 xor 0 => False

This is because it's a Boolean operator, so it should fall back to
Boolean values when necessary, like 'not':

     not 0 => True
     not 1 => False

Also:

     x and y and z => (x and y) and z
     x or y or z => (x or y) or z

therefore:

     x xor y xor z => (x xor y) xor z


From skip at pobox.com  Wed Jul 15 10:22:11 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 15 Jul 2009 09:22:11 -0500
Subject: [Python-projects] [TIP] Teaching pylint about keyword
	placeholders in string formatting
In-Reply-To: <20090715103948.GA6248@volans.logilab.fr>
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
Message-ID: <19037.58899.828799.617599@montanaro.dyndns.org>


    Nicolas> Here is the ticket:
    Nicolas> https://www.logilab.net/elo/ticket/9634

Is it possible to get read-only access to the tracker?  It's prompting me
for a login which I don't have.

Thx,

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    when i wake up with a heart rate below 40, i head right for the espresso
    machine. -- chaos @ forums.usms.org


From piet at cs.uu.nl  Wed Jul 15 10:25:14 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 16:25:14 +0200
Subject: promlems with threading and print
References: <mailman.3139.1247646986.8015.python-list@python.org>
	<m2k52axmap.fsf@cs.uu.nl>
Message-ID: <m2eisixbud.fsf@cs.uu.nl>

>>>>> Piet van Oostrum <piet at cs.uu.nl> (PvO) wrote:

>PvO>     def run(self):
>PvO>         with lock:

All the 'with lock:' lines should have been 'with self.lock:' but as
lock is also a global variable, it did work. Of course you can decide to
use only the global variable and get rid of the self.lock altogether. I
am not very fond of global variables myself, however, that's why I used
the self.lock.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aurelien.campeas at logilab.fr  Wed Jul 15 10:33:04 2009
From: aurelien.campeas at logilab.fr (=?utf-8?B?QXVyw6lsaWVuIENhbXDDqWFz?=)
Date: Wed, 15 Jul 2009 16:33:04 +0200
Subject: [Python-projects] [TIP] Teaching pylint about keyword
	placeholders in string formatting
In-Reply-To: <19037.58899.828799.617599@montanaro.dyndns.org>
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
	<19037.58899.828799.617599@montanaro.dyndns.org>
Message-ID: <20090715143304.GJ10884@crater.logilab.fr>

On Wed, Jul 15, 2009 at 09:22:11AM -0500, skip at pobox.com wrote:
> 
>     Nicolas> Here is the ticket:
>     Nicolas> https://www.logilab.net/elo/ticket/9634
> 
> Is it possible to get read-only access to the tracker?  It's prompting me
> for a login which I don't have.
> 
> Thx,

that should be http://www.logilab.org/ticket/9634



From Bill at SynectixLtd.com  Wed Jul 15 10:37:54 2009
From: Bill at SynectixLtd.com (Bill Davy)
Date: Wed, 15 Jul 2009 15:37:54 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org><pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<mailman.3158.1247667680.8015.python-list@python.org>
Message-ID: <6Yidnc7fb6QvdMDXnZ2dnUVZ8h6dnZ2d@bt.com>

"MRAB" <python at mrabarnett.plus.com> wrote in message 
news:mailman.3158.1247667680.8015.python-list at python.org...
> Steven D'Aprano wrote:
>> On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
>>
>>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>>> to have an 'xor' operator as well.
>>
>> I've often wished there was too, for the sake of completeness and 
>> aesthetics, I'd love to be able to write:
>>
>> a xor b
>>
>> instead of defining a function xor(a, b).
>>
>> Unfortunately, outside of boolean algebra and simulating electrical 
>> circuits, I can't think of any use-cases for an xor operator. Do you have 
>> any?
>>
> The problem is that 'and' and 'or' are not limited to Boolean values:
>
>     'and' returns the first false value or the last true value.
>
>     'or' returns the first true value or the last false value.
>
> What values should 'xor' return? IMHO, if only one of the values is true
> then it should return that value, otherwise it should return False.
>
>     1 xor 0 => 1
>     0 xor 2 => 2
>     1 xor 2 => False
>     0 xor 0 => False
>
> This is because it's a Boolean operator, so it should fall back to
> Boolean values when necessary, like 'not':
>
>     not 0 => True
>     not 1 => False
>
> Also:
>
>     x and y and z => (x and y) and z
>     x or y or z => (x or y) or z
>
> therefore:
>
>     x xor y xor z => (x xor y) xor z


Gosh, let's all discuss commutation and distribution.

And surely in quantum merchanics there is something about non-commuting 
operatiomns letting in Planck's constant. 




From tycho at tycho.ws  Wed Jul 15 10:58:03 2009
From: tycho at tycho.ws (Tycho Andersen)
Date: Wed, 15 Jul 2009 09:58:03 -0500
Subject: import module unbelieveable behaviour
In-Reply-To: <200907151512.52607.peter.fodrek@stuba.sk>
References: <200907151512.52607.peter.fodrek@stuba.sk>
Message-ID: <49b3a7400907150758j77e97e95ra9b806e763eb22da@mail.gmail.com>

On Wed, Jul 15, 2009 at 8:12 AM, Peter Fodrek<peter.fodrek at stuba.sk> wrote:
>
> Would anyone be helpful for me to get more information about this problem
> because ?pydb does not show anything usable for me,please?

What is the directory structure for the HeeksCNC module? Although I'm
no expert, I suspect it looks something like:

nc/
nc/rez.py
nc/foo.py

In order for python to look in the nc/ directory for modules, there
needs to be a file called __init__.py (even if it's empty). I suspect
the nc/ directory is missing this file (although, I'm confused as to
why it would work in the interpreter then).

Tycho


From jeanmichel at sequans.com  Wed Jul 15 11:00:39 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 17:00:39 +0200
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
Message-ID: <4A5DEF17.3050107@sequans.com>

John Nagle wrote:
> walterbyrd wrote:
>> I believe Guido himself has said that all indentions should be four
>> spaces - no tabs.
>>
>> Since backward compatibility is being thrown away anyway, why not
>> enforce the four space rule?
>>
>> At least that way, when I get python code from somebody else, I would
>> know what I am looking at, without having to do a hex dump, or
>> something.
>
>    Python 3 enforces the rule that you can't mix tabs and spaces
> for indentation in the same file.  That (finally) guarantees that
> the indentation you see is what the Python parser sees.  That's
> enough to prevent non-visible indentation errors.
>
>    It also means that the Python parser no longer has to have
> any concept of how many spaces equal a tab.  So the problem
> is now essentially solved.
>
>                     John Nagle
By the way why would you prevent us from using tabs for indenting ? If 
I'm not wrong, from a semantic point of view, that's what tabs are for: 
indenting. Spaces are meant to separate tokens, aren't they ?
I love my tabs, don't take them away from me !

JM


From jeanmichel at sequans.com  Wed Jul 15 11:03:30 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 17:03:30 +0200
Subject: Colour of output text
In-Reply-To: <pan.2009.07.11.06.24.02.406000@nowhere.com>
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com>
	<h371ba$36l$1@aioe.org>
	<pan.2009.07.11.06.24.02.406000@nowhere.com>
Message-ID: <4A5DEFC2.4030602@sequans.com>

Nobody wrote:
> On Fri, 10 Jul 2009 09:23:54 +0000, garabik-news-2005-05 wrote:
>
>   
>>>> I would like to learn a way of changing the colour of a particular
>>>> part of the output text. I've tried the following
>>>>         
>>> On Unix operating systems this would be done through the curses interface:
>>>
>>> http://docs.python.org/library/curses.html
>>>       
>> Or using ANSI colour codes:
>>
>> colours = {
>>             'none'       :    "",
>>             'default'    :    "\033[0m",
>>             'bold'       :    "\033[1m",
>>     
>
> [snip]
>
>   
>>             # non-standard attributes, supported by some terminals 
>>     
>
> This comment should have appeared immediately after "none" ;)
>
> Hard-coding control/escape sequences is just lame. Use the curses modules
> to obtain the correct sequences for the terminal.
>
>   
As the OP I'm really interested in doing so. I currently have all my 
colors hard-coded.
Now It may be lame but as soon as I call curses.initscr(), it's just 
messing up with my terminal, moreover I didn't figure out how to "print  
'hello'" using curses color codes.
Anyone has an example ? I'm pretty sure it may fit in one line.

JM




From jeanmichel at sequans.com  Wed Jul 15 11:15:47 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 17:15:47 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3j358$lhr$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
Message-ID: <4A5DF2A3.2080101@sequans.com>

Christian Heimes wrote:
> Chris Rebert wrote:
>   
>> Using the xor bitwise operator is also an option:
>> bool(x) ^ bool(y)
>>     
>
> I prefer something like:
>
>     bool(a) + bool(b) == 1
>
> It works even for multiple tests (super xor):
>
>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>       raise ValueError("Exactly one of a, b, c and d must be true")
>
> Christian
>
>   
While everyone's trying to tell the OP how to workaround the missing xor 
operator, nobody answered the question "why is there no xor operator ?".

If the question was "Why is there no 'or' operator ?", would "because A 
or B <=> not(not A and not B)" be a proper answer ?

JM



From MrJean1 at gmail.com  Wed Jul 15 11:15:55 2009
From: MrJean1 at gmail.com (Jean)
Date: Wed, 15 Jul 2009 08:15:55 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <c7abf5e2-7ada-4bda-8c61-9b65132e704a@c1g2000yqi.googlegroups.com>

On Jul 13, 6:26?am, seldan24 <selda... at gmail.com> wrote:
> Hello,
>
> I'm fairly new at Python so hopefully this question won't be too
> awful. ?I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).
> I've figured out two different ways to do this, and am wondering which
> is the best (i.e. cleanest, 'right' way to proceed). ?I'm also trying
> to understand exactly what occurs for each one.
>
> The first example:
>
> from ftplib import FTP
> try:
> ? ? ftp = FTP(ftp_host)
> ? ? ftp.login(ftp_user, ftp_pass)
> except Exception, err:
> ? ? print err
>
> This works fine. ?I read through the documentation, and my
> understanding is that there is a built-in exceptions module in python,
> that is automatically available in a built-in namespace. ?Within that
> module is an 'Exception' class which would contain whatever exception
> is thrown. ?So, I'm passing that to the except, along with err to hold
> the value and then print it out.
>
> The second example:
>
> from ftplib import FTP
> import sys
> try:
> ? ? ftp = FTP(ftp_host)
> ? ? ftp.login(ftp_user, ftp_pass)
> except:
> ? ? print sys.exc_info()
>
> Here I, for the most part, get the same thing. ?I'm not passing
> anything to except and just printing out the exception using a method
> defined in the sys module.
>
> So, I'm new to Python... I've made it this far and am happy, but want
> to make sure I'm coding correctly from the start. ?Which method is the
> better/cleaner/more standard way to continue? ?Thanks for any help.



The second example is "better" if you need your code to work in Python
3.0 *and* in 2.X.

For Python 3.0, the first example has to be written as:

    ....
except Exception as err:
    ....


/Jean Brouwers


From skip at pobox.com  Wed Jul 15 11:23:22 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 15 Jul 2009 10:23:22 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <4A5DEF17.3050107@sequans.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<4A5DEF17.3050107@sequans.com>
Message-ID: <19037.62570.370235.287125@montanaro.dyndns.org>


    JM> By the way why would you prevent us from using tabs for indenting ?
    JM> If I'm not wrong, from a semantic point of view, that's what tabs
    JM> are for: indenting. Spaces are meant to separate tokens, aren't they
    JM> ?  I love my tabs, don't take them away from me !

I don't think your tabs have been taken away, you just can't mix them with
spaces.

Skip


From python-url at phaseit.net  Wed Jul 15 11:36:06 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Wed, 15 Jul 2009 15:36:06 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul 15)
Message-ID: <h3kt16$9nj$1@lairds.us>

QOTW:  "Everyone gets so caught up in programming via languages that you get,
well, people trying to teach 'Computer Programming' as if it were only
necessary to grok a language, rather than grokking /symbol manipulation/
itself." - Simon Forman
    http://groups.google.com/group/comp.lang.python/msg/4bc886a5d5feda14
    

    A C programmer may completely fail to guess the actual meaning of ++n
    and --n in Python:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/fa7281ce6249dec5/
    
    Building the argument list for a subprocess call *right* wasn't obvious:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/f02150fbc732f9dc/
    
    Robust way to handle all possible exceptions:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/db858ef8dfb51a47/
    
    A related question: how to safely handle Ctrl-C:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/a3ef46f47a0eac39/
    
    Started two weeks ago, this thread is now discussing about the correct
    usage of "assert":
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b1a6ca84d3bfc483/
    
    Looking for a robust and safe way of writing a constructor when any step
    may fail:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/1dc1f1cb5fa8177a/
    
    How to define a "class" property (as opposed to normal, "instance"
    properties):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8a8b8138eada2be5/
    
    How to explain basic concepts like pass-by-object, assignment and
    mutability to beginners:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/4b5c5aa1d8b42b9c/
    later: the meaning of '=' in assignment
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3c13fd526a4d35df/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From robert.kern at gmail.com  Wed Jul 15 11:38:55 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 15 Jul 2009 10:38:55 -0500
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5DF2A3.2080101@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>
	<4A5DF2A3.2080101@sequans.com>
Message-ID: <h3kt6i$cij$1@ger.gmane.org>

On 2009-07-15 10:15, Jean-Michel Pichavant wrote:
> Christian Heimes wrote:
>> Chris Rebert wrote:
>>> Using the xor bitwise operator is also an option:
>>> bool(x) ^ bool(y)
>>
>> I prefer something like:
>>
>> bool(a) + bool(b) == 1
>>
>> It works even for multiple tests (super xor):
>>
>> if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>> raise ValueError("Exactly one of a, b, c and d must be true")
>>
>> Christian
>>
> While everyone's trying to tell the OP how to workaround the missing xor
> operator, nobody answered the question "why is there no xor operator ?".
>
> If the question was "Why is there no 'or' operator ?", would "because A
> or B <=> not(not A and not B)" be a proper answer ?

That's not the only answer the OP has been given. The most compelling answer is 
that an "xor" keyword cannot be implemented with similar semantics to "and" and 
"or", in particular short-circuiting and returning one of the actual inputs 
instead of a coerced bool.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From deets at nospam.web.de  Wed Jul 15 11:41:54 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 17:41:54 +0200
Subject: import module unbelieveable behaviour
References: <mailman.3157.1247667587.8015.python-list@python.org>
Message-ID: <7c6bdkF26j00sU1@mid.uni-berlin.de>

Peter Fodrek wrote:

> Dear conference!
> 
> I have test Why python based script for HeeksCNC post-processing does not
> work...  And I've got unbelievable behavior  When importing module module
> manually it works, but same opertaion from script does not
>  work as seen
> 
> /opt/HeeksCAD8/HeeksCNC> python
> Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
> [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import nc.rez
>>>>
> /opt/HeeksCAD8/HeeksCNC> python test.py
> Traceback (most recent call last):
>   File "test.py", line 7, in <module>
>     import nc.rez
> ImportError: No module named rez

What does 

import nc
print nc.__file__

tell you, and is that what you'd expect it to be?

Diez


From hniksic at xemacs.org  Wed Jul 15 12:14:10 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Wed, 15 Jul 2009 18:14:10 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
Message-ID: <87fxcxj54d.fsf@busola.homelinux.net>

Jean-Michel Pichavant <jeanmichel at sequans.com> writes:

> While everyone's trying to tell the OP how to workaround the missing
> xor operator, nobody answered the question "why is there no [boolean]
> xor operator ?".

Probably because there isn't one in C.  The bitwise XOR operator, on the
other hand, exists in both C and Python.

> If the question was "Why is there no 'or' operator ?", would "because
> A or B <=> not(not A and not B)" be a proper answer ?

Note that in Python A or B is in fact not equivalent to not(not A and
not B).


From ethan at stoneleaf.us  Wed Jul 15 12:25:08 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 15 Jul 2009 09:25:08 -0700
Subject: convert Dbase (.dbf) files to SQLite databases
In-Reply-To: <7c5n8kF25pc8bU1@mid.dfncis.de>
References: <7c5n8kF25pc8bU1@mid.dfncis.de>
Message-ID: <4A5E02E4.9090303@stoneleaf.us>

Helmut Jarausch wrote:
> Hi,
> 
> I have a lot of old Dbase files (.dbf) and I'll like to convert these
> to SQLite databases as automatically as possible.
> Does anybody know a tool/Python script to do so?
> 
> I know, I could use dbfpy and create the SQLite table and import all
> data. But is there something easier?
> 
> Many thanks for a hint,
> 
> Helmut.
> 

Greetings!

If your tables are either dBase III or Visual Foxpro 6 (may work with 
other VFP versions...) you can try 
http://groups.google.com/group/python-dbase

#open table
import dbf
table = dbf.Table('/path/to/old/dbf')

#generate .csv file
table.export()	# defaults to same name with csv extension

#access records
for rec in table:
     tups = tuple(rec)
     lst = list(rec)
     dct = rec.scatter_fields()

I haven't used SQlite, so I'm unable to provide samples for that portion 
of the conversion.

Hope this helps.

~Ethan~


From sjmachin at lexicon.net  Wed Jul 15 12:30:29 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 15 Jul 2009 09:30:29 -0700 (PDT)
Subject: convert Dbase (.dbf) files to SQLite databases
References: <7c5n8kF25pc8bU1@mid.dfncis.de>
	<mailman.3145.1247654594.8015.python-list@python.org>
Message-ID: <419cc0e0-3a78-4906-8420-c12ce2684bef@c36g2000yqn.googlegroups.com>

On Jul 15, 8:39?pm, David Lyon <david.l... at preisshare.net> wrote:
> On Wed, 15 Jul 2009 11:53:28 +0200, Helmut Jarausch
>
> <jarau... at igpm.rwth-aachen.de> wrote:
> > Hi,
>
> > I have a lot of old Dbase files (.dbf) and I'll like to convert these
> > to SQLite databases as automatically as possible.
> > Does anybody know a tool/Python script to do so?
>
> > I know, I could use dbfpy and create the SQLite table and import all
> > data. But is there something easier?
>
> yes...
>
> Use OpenOffice-Scalc or MS-Office-Excel to open the table...

Max 64K rows for Scalc and Excel 2003; 2007 can take 2**20 rows.
Only old dBase (not dBase 7). Memo fields not handled. Visual FoxPro
DBFs not supported by Excel even tho' VFP is an MS product.


> Export to csv....

Yuk.

>
> Use SQLite Manager (https://addons.mozilla.org/en-US/firefox/addon/5817)
>
> and use the import wizard to import your data....
>
> It shouldn't take too long...

... before you get sick of the error-prone manual tasks.

I'd write a script that took a DBF file, analysed the field
descriptions, made a CREATE TABLE statement, executed it, and then
started doing inserts. Fairly easy to write. Scripts have the great
benefit that you can fix them and re-run a whole lot easier than
redoing manual steps.

If dbfpy can't handle any new-fangled stuff you may have in your
files, drop me a line ... I have a soon-to-be released DBF module that
should be able to read the "new" stuff up to dBase7 and VFP9,
including memo files, conversion from whatever to Unicode if
needed, ...

Cheers,
John


From seldan24 at gmail.com  Wed Jul 15 12:36:13 2009
From: seldan24 at gmail.com (seldan24)
Date: Wed, 15 Jul 2009 09:36:13 -0700 (PDT)
Subject: Python Equivalent for dd & fold
Message-ID: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>

Hello,

I have a shell script, that I'm attempting to convert to Python.  It
FTP's files down from an AS/400 machine.  That part is working fine.
Once the files arrive, the script converts them from EBCDIC to ASCII
and then formats their line width based on a pre-determined size.

For example, if I have the file TESTFILE and I know it should be
formatted to 32 characters/line, I run:

dd if=TESTFILE,EBCDIC conv=ASCII | fold -w 32 > TESTFILE.ASCII

Luckily, the files have the packed decimal format common in COBOL
programs converted already prior to reaching me, so all I have to do
is the conversion and line width formatting.  The above works fine,
and I know I could (and may) just embed it using subprocess.Popen.
This, I've figured out how to do.  But, ideally, I'd like to convert
as much shell to native Python as possible, so that I can learn more.

I think I can figure out the first part by using the codecs module...
found some information on Google related to that.  My question is,
what can I use as the equivalent for the Unix 'fold' command?  I don't
really need to know how to do it, just a push in the right direction.

Thanks.


From rhodri at wildebst.demon.co.uk  Wed Jul 15 12:40:20 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 15 Jul 2009 17:40:20 +0100
Subject: select lines in python
In-Reply-To: <29449.210.212.36.65.1247598632.squirrel@www.iisermohali.ac.in>
References: <29449.210.212.36.65.1247598632.squirrel@www.iisermohali.ac.in>
Message-ID: <op.uw4a9iv6a8ncjz@gnudebst>

On Tue, 14 Jul 2009 20:10:32 +0100, <amrita at iisermohali.ac.in> wrote:

> Can i become more precise like instead of printing all lines for PHE and
> ASP is it possible that for PHE python will print only those lines which
> will have information about H and HA and for ASP it will print those  
> lines
> which will have information about HA and HB.

1) Top-posting is considered unhelpful, since it breaks the flow of
information badly.

2) To answer question: yes, you can.  However I can sense the start of an
unending flood of small changes, so I'm going to direct you back to the
Python tutorial at www.python.org rather than tell you exactly how.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From ethan at stoneleaf.us  Wed Jul 15 12:44:53 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 15 Jul 2009 09:44:53 -0700
Subject: convert Dbase (.dbf) files to SQLite databases
In-Reply-To: <419cc0e0-3a78-4906-8420-c12ce2684bef@c36g2000yqn.googlegroups.com>
References: <7c5n8kF25pc8bU1@mid.dfncis.de>	<mailman.3145.1247654594.8015.python-list@python.org>
	<419cc0e0-3a78-4906-8420-c12ce2684bef@c36g2000yqn.googlegroups.com>
Message-ID: <4A5E0785.8060307@stoneleaf.us>

John Machin wrote:

> If dbfpy can't handle any new-fangled stuff you may have in your
> files, drop me a line ... I have a soon-to-be released DBF module that
> should be able to read the "new" stuff up to dBase7 and VFP9,
> including memo files, conversion from whatever to Unicode if
> needed, ...
> 
> Cheers,
> John

Cool!  I'm looking forward to it!

~Ethan~


From motoom at xs4all.nl  Wed Jul 15 12:47:13 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Wed, 15 Jul 2009 18:47:13 +0200
Subject: Python Equivalent for dd & fold
In-Reply-To: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
Message-ID: <4A5E0811.2050800@xs4all.nl>

seldan24 wrote:

> what can I use as the equivalent for the Unix 'fold' command?

def fold(s,len):
     while s:
         print s[:len]
         s=s[len:]

s="A very long string indeed. Really that long? Indeed."
fold(s,10)

Output:

A very lon
g string i
ndeed. Rea
lly that l
ong? Indee
d.

Greetings,

-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From weafon at lbl.gov  Wed Jul 15 12:48:49 2009
From: weafon at lbl.gov (weafon)
Date: Wed, 15 Jul 2009 09:48:49 -0700
Subject: How to keep a function as a generator function when the yield
	operator	is moved into its sub-functions??
In-Reply-To: <4A5D4DC5.1090202@ieee.org>
References: <4A5CC86A.9070907@lbl.gov> <4A5D4DC5.1090202@ieee.org>
Message-ID: <4A5E0871.90105@lbl.gov>

Hi DaveA,

Thank for your responses even though my problem has been solved based on 
Miles' suggestion. I am writing programs by using the SimPy library, 
which is a discrete-event simulator library. Below is my actual code segment

class RAID(Process):
    def ReqServ(self):
        while(now()<TM_End):
            yield get, self, self.queue, 1
            orig_req=self.got[0]
            ....
            for devno in range (5):
                ...
                #---- Segment A begins
               new_loc= calcfunc(orig_req.loc)
               new_len= calcfunc(orig_req.len)
               new_req1=   Req(self.cn_req, new_loc, new_len)
               yield put, self, self.disks[devno].queue,[new_req]
               self.cn_req+=1
               new_req2=   Req(self.cn_req, new_loc, new_len)
               yield put, self, self.disks[devno+5].queue,[new_req]
               self.cn_req+=1
               #--- Segment A ends
               ...

In the above example, ReqServ may pause at three lines of yield and 
return something. However, if I move the code segment A into a second 
function as following, then ReqServ will not pause and return things 
back to its caller after calling SegmentA().

class RAID(Process):
    def ReqServ(self):
        while(now()<TM_End):
            yield get, self, self.queue, 1
            orig_req=self.got[0]
            ....
            for devno in range (5):
                ...
                self.SegmentA(orig_req.loc,orig_req.len)
                ...

    def SegmentA(self,loc,len):
        new_loc= calcfunc(loc)
        new_len= calcfunc(len)
        new_req1=   Req(self.cn_req, new_loc, new_len)
        yield put, self, self.disks[devno].queue,[new_req]
        self.cn_req+=1
        new_req2=   Req(self.cn_req, new_loc, new_len)
        yield put, self, self.disks[devno+5].queue,[new_req]
        self.cn_req+=1

Based on Miles's suggestion, we can solve the problem by using 'return' 
in SegmentA() and keeping 'yield' in ReqServ(). For example,

class RAID(Process):
    def ReqServ(self):
        while(now()<TM_End):
            yield get, self, self.queue, 1
            orig_req=self.got[0]
            ....
            for devno in range (5):
                ...
                yield self.SegmentA(orig_req.loc,orig_req.len,0)
                yield self.SegmentA(orig_req.loc,orig_req.len,5)
                ...

    def SegmentA(self,loc,len,shiftno):
        new_loc= calcfunc(loc)
        new_len= calcfunc(len)
        new_req=   Req(self.cn_req, new_loc, new_len)
        self.cn_req+=1
        return put, self, self.disks[devno+shiftno].queue,[new_req]


Regards,
Weafon

Dave Angel wrote:
> weafon wrote:
>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Hi guys,
>>
>> I have a question about the usage of yield. As shown in the below 
>> example, in general, if there is a code segment commonly used by two 
>> or more functions, we may isolate the segment into a function and 
>> then call it from other functions if necessary.
>>
>> def func1():
>>    ....
>>    while(cond):
>>        .....
>>        commoncode()
>>        ...
>>
>>
>> def func2():
>>    ....
>>    while(cond):
>>        .....
>>        commoncode()
>>        ...
>>
>> def commoncode()
>>    AAAA
>>    BBBB
>>    CCCC
>>
>> However, if there is a 'yield' operation in the common code segment, 
>> the isolation causes that func1 and func2 become a non-generator 
>> function!! Although I can prevent such an isolation by just 
>> duplicating the segment in func1 and func2 to keep both of them being 
>> generator functions, the code may become ugly and hard to maintain 
>> particularly when coomoncode() is long.
>>
>> The problem may be resolved if I can define the commoncode() as an 
>> inline function or marco. Unfortunately, inline and marco do not 
>> seems to be implemented in python. Thus, how can I isolate a common 
>> segment into a function when there are yield operations in the common 
>> segment?
>>
>> Thanks,
>> Weafon
>>
> You are implying there's something special or unique about yield in 
> this.  Return has the same problem, and many other flow control 
> constructs.   Also, variable definitions and scoping.
>
> So you can't just copy any old bunch of adjacent lines out of two 
> functions, put it into a third, and call it factoring.  Give us a 
> specific example you're puzzled about, and we can try to solve it.
>
> DaveA
>



From seldan24 at gmail.com  Wed Jul 15 13:14:54 2009
From: seldan24 at gmail.com (seldan24)
Date: Wed, 15 Jul 2009 10:14:54 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
Message-ID: <e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>

On Jul 15, 12:47?pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> seldan24 wrote:
> > what can I use as the equivalent for the Unix 'fold' command?
>
> def fold(s,len):
> ? ? ?while s:
> ? ? ? ? ?print s[:len]
> ? ? ? ? ?s=s[len:]
>
> s="A very long string indeed. Really that long? Indeed."
> fold(s,10)
>
> Output:
>
> A very lon
> g string i
> ndeed. Rea
> lly that l
> ong? Indee
> d.
>
> Greetings,
>
> --
> "The ability of the OSS process to collect and harness
> the collective IQ of thousands of individuals across
> the Internet is simply amazing." - Vinod Valloppillilhttp://www.catb.org/~esr/halloween/halloween4.html

Wow, I feel like a dork.  I should have done more research prior to
posting.  Anyway, thanks for the advice.  The trouble with Python is
that things make 'too much' sense.  Loving this language.


From python at mrabarnett.plus.com  Wed Jul 15 13:23:14 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 15 Jul 2009 18:23:14 +0100
Subject: Python Equivalent for dd & fold
In-Reply-To: <e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
Message-ID: <4A5E1082.8090901@mrabarnett.plus.com>

seldan24 wrote:
> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>> seldan24 wrote:
>>> what can I use as the equivalent for the Unix 'fold' command?
>> def fold(s,len):
>>      while s:
>>          print s[:len]
>>          s=s[len:]
>>
>> s="A very long string indeed. Really that long? Indeed."
>> fold(s,10)
>>
>> Output:
>>
>> A very lon
>> g string i
>> ndeed. Rea
>> lly that l
>> ong? Indee
>> d.
>>
> 
> Wow, I feel like a dork.  I should have done more research prior to
> posting.  Anyway, thanks for the advice.  The trouble with Python is
> that things make 'too much' sense.  Loving this language.

You might still need to tweak the above code as regards how line endings
are handled.


From http  Wed Jul 15 13:25:25 2009
From: http (Paul Rubin)
Date: 15 Jul 2009 10:25:25 -0700
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <7x4otdeu4a.fsf@ruckus.brouhaha.com>

Hrvoje Niksic <hniksic at xemacs.org> writes:
> > While everyone's trying to tell the OP how to workaround the missing
> > xor operator, nobody answered the question "why is there no [boolean]
> > xor operator ?".
> 
> Probably because there isn't one in C.  The bitwise XOR operator, on the
> other hand, exists in both C and Python.

A non-bitwise XOR really sounds almost useless.


From wbrehaut at mcsnet.ca  Wed Jul 15 13:36:21 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 11:36:21 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<mailman.3119.1247612922.8015.python-list@python.org>
	<522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
	<mailman.3152.1247657854.8015.python-list@python.org>
Message-ID: <id4s55t1sgco9gr3l61d308jg5gj06rhp1@4ax.com>

On Wed, 15 Jul 2009 13:37:22 +0200, Christian Heimes
<lists at cheimes.de> wrote:

>pdpi wrote:
>> On Jul 15, 12:08 am, Christian Heimes <li... at cheimes.de> wrote:
>>> Chris Rebert wrote:
>>>> Using the xor bitwise operator is also an option:
>>>> bool(x) ^ bool(y)
>>> I prefer something like:
>>>
>>>     bool(a) + bool(b) == 1
>>>
>>> It works even for multiple tests (super xor):
>>>
>>>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>>>       raise ValueError("Exactly one of a, b, c and d must be true")
>>>
>>> Christian
>> 
>> "if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
>> xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
>> 1 = 0 xor 1 = 1 if you assicate to the left)
>
>I'm well aware of the fact that I've described something differently.
>'xor' can be explained as 'check if exactly one element of two elements
>is true'. My algorithms describes a super xor, aka 'check if exactly one
>element of n elements is true'.

But that's not a "super xor" (commonly known as XOR). Rather than
describing xor as:

	check if exactly one element of two elements is true

describe it as:

	check if an odd number of two elements is true

then you'll get the correct definition of "super xor":

	check if an odd number of n elements is true

I.e., XOR determines parity, and:

	XOR <some binary vector v> =
		0 if v has an even number of 1s and 
		1 if v has an odd number of 1s

wayne

>Christian


From jeanmichel at sequans.com  Wed Jul 15 13:43:20 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 19:43:20 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <87fxcxj54d.fsf@busola.homelinux.net>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <4A5E1538.7030107@sequans.com>

Hrvoje Niksic wrote:
[snip]
> Note that in Python A or B is in fact not equivalent to not(not A and
> not B).
>   
 >>> l = [(True, True), (True, False), (False, True), (False, False)]
 >>> for p in l:
...     p[0] or p[1]
...
True
True
True
False
 >>> for p in l:
...     not(not p[0] and not p[1])
...
True
True
True
False
 >>>      

Did I make twice the same obvious error ?

JM


From emile at fenx.com  Wed Jul 15 13:48:42 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 15 Jul 2009 10:48:42 -0700
Subject: Python Equivalent for dd & fold
In-Reply-To: <4A5E1082.8090901@mrabarnett.plus.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
Message-ID: <h3l4kc$57c$1@ger.gmane.org>

On 7/15/2009 10:23 AM MRAB said...
>> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>>> seldan24 wrote:
>>>> what can I use as the equivalent for the Unix 'fold' command?
>>> def fold(s,len):
>>>      while s:
>>>          print s[:len]
>>>          s=s[len:]
>>>
<snip>
> You might still need to tweak the above code as regards how line endings
> are handled.

You might also want to tweak it if the strings are _really_ long to 
simply slice out the substrings as opposed to reassigning the balance to 
a newly created s on each iteration.

Emile



From emile at fenx.com  Wed Jul 15 13:55:22 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 15 Jul 2009 10:55:22 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5E1538.7030107@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
Message-ID: <h3l50s$71e$1@ger.gmane.org>

On 7/15/2009 10:43 AM Jean-Michel Pichavant said...
> Hrvoje Niksic wrote:
> [snip]
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>>   
>  >>> l = [(True, True), (True, False), (False, True), (False, False)]
>  >>> for p in l:
> ...     p[0] or p[1]
> ...
> True
> True
> True
> False
>  >>> for p in l:
> ...     not(not p[0] and not p[1])
> ...
> True
> True
> True
> False
>  >>>     
> Did I make twice the same obvious error ?

No -- but in the not(not... example it doesn't short-circuit.

Emile



From rodriguealcazar at gmail.com  Wed Jul 15 13:55:34 2009
From: rodriguealcazar at gmail.com (Rodrigue)
Date: Wed, 15 Jul 2009 10:55:34 -0700 (PDT)
Subject: python first assignment of a global variable
Message-ID: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>

Hi all,

I came accross a strange behaviour in python today. Here is a simple
example to describe my situation:

MY_GLOBAL = ''

def a():
    print 'global is: ', MY_GLOBAL

def b():
    try:
        MY_GLOBAL += 'bla'
    except Exception, e:
        print 'b: ', e

def c():
    try:
        global MY_GLOBAL
        MY_GLOBAL += 'bla'
    except Exception, e:
        print 'c: ', e

def d():
    try:
        if not MY_GLOBAL:
            print 'not my global'
    except Exception, e:
        print 'd: ', e

def e():
    try:
        if not MY_GLOBAL:
            MY_GLOBAL = ''
    except Exception, e:
        print 'e: ', e

def f():
    global MY_GLOBAL
    if not MY_GLOBAL:
        MY_GLOBAL = ''

def e_raise():
    if not MY_GLOBAL:
        MY_GLOBAL = 'bla'

if __name__ == "__main__":
    a()
    b()
    c()
    d()
    e()
    f()
    e_raise()


And here is the output I get:

global is:
b:  local variable 'MY_GLOBAL' referenced before assignment
e:  local variable 'MY_GLOBAL' referenced before assignment
Traceback (most recent call last):
  File "glo.py", line 49, in <module>
    e_raise()
  File "glo.py", line 39, in e_raise
    if not MY_GLOBAL:
UnboundLocalError: local variable 'MY_GLOBAL' referenced before
assignment


Now, I was reading that page http://stackoverflow.com/questions/370357/python-variable-scope-question
and found (understood) only part of the behaviour that could explain
the output.

Basically, I was very surprised to discover that e() raises an
exception, but even more that e_raise() points to
if not MY_GLOBAL Is the problem not really when I assign?

My assumption is that some reordering is happening behind the scenes
that creates a situation similar to the += which assigns hence expects
to be at the local level.

I would love some enlightenment here

Rodrigue


From milesck at umich.edu  Wed Jul 15 13:57:20 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 13:57:20 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5E1538.7030107@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
Message-ID: <ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>


On Jul 15, 2009, at 1:43 PM, Jean-Michel Pichavant wrote:

> Hrvoje Niksic wrote:
> [snip]
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>>
> >>> l = [(True, True), (True, False), (False, True), (False, False)]
> >>> for p in l:
> ...     p[0] or p[1]
> [snip]
> Did I make twice the same obvious error ?


Try again with:

l = [('foo','bar'), ('foo', ''), ('', 'bar'), ('', '')]

-Miles



From milesck at umich.edu  Wed Jul 15 14:10:50 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 14:10:50 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3l50s$71e$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com> <h3l50s$71e$1@ger.gmane.org>
Message-ID: <D7CCEA0C-2AAC-473D-9081-2EE690D82BC7@umich.edu>

On Jul 15, 2009, at 1:55 PM, Emile van Sebille wrote:
> On 7/15/2009 10:43 AM Jean-Michel Pichavant said...
>> Hrvoje Niksic wrote:
>> [snip]
>>> Note that in Python A or B is in fact not equivalent to not(not A  
>>> and
>>> not B).
>>>
>> Did I make twice the same obvious error ?
>
> No -- but in the not(not... example it doesn't short-circuit.

No; like 'A or B', 'not (not A and not B)' does in fact short-circuit  
if A is True.  (The 'and' condition does not have to evaluate the  
right operand when 'not A' is False.)

-Miles



From tjreedy at udel.edu  Wed Jul 15 14:14:55 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 15 Jul 2009 14:14:55 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5DA247.3040606@timgolden.me.uk>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<4A5DA247.3040606@timgolden.me.uk>
Message-ID: <h3l6at$bjd$1@ger.gmane.org>

Tim Golden wrote:

> I was pondering on this yesterday, and the only case I've
> come across in my code -- and it's reasonably common --
> is checking that one and only one of two params has been
> passed. I have code which wants, say, an id or a name
> but doesn't want both. It's hardly difficult to write the
> check even now, but an built-in xor would make it fractionally
> cleaner.

I think I would just have one parameter id_name or identifier so no 
check is needed. This is a common idiom in Python where names are not 
typed. Example: param 'source' is a string (with a file name to be 
opened) or an already opened file. If you want two local vars inside the 
function, that should be kept private to the function.

tjr



From emile at fenx.com  Wed Jul 15 14:14:57 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 15 Jul 2009 11:14:57 -0700
Subject: python first assignment of a global variable
In-Reply-To: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
References: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
Message-ID: <h3l65k$b4q$1@ger.gmane.org>

On 7/15/2009 10:55 AM Rodrigue said...
> I came accross a strange behaviour in python today. Here is a simple
> example to describe my situation:
> 
> MY_GLOBAL = ''

<snip>

> def e_raise():
>     if not MY_GLOBAL:
>         MY_GLOBAL = 'bla'
> 

<snip>

> Traceback (most recent call last):
>   File "glo.py", line 49, in <module>
>     e_raise()
>   File "glo.py", line 39, in e_raise
>     if not MY_GLOBAL:
> UnboundLocalError: local variable 'MY_GLOBAL' referenced before
> assignment

the def prepares the function for subsequent use.  At this prep time, 
MY_GLOBAL, by virtue of being assigned to later in the function, and the 
absence of a global statement, is identified as a local variable. 
Later, at execution time, testing MY_GLOBAL fails as it's not yet been 
assigned to.

HTH,

Emile



From milesck at umich.edu  Wed Jul 15 14:17:27 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 14:17:27 -0400
Subject: python first assignment of a global variable
In-Reply-To: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
References: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
Message-ID: <4C9A140E-7BAB-49F5-97B7-FAD86DD0E2CF@umich.edu>

On Jul 15, 2009, at 1:55 PM, Rodrigue wrote:

> Basically, I was very surprised to discover that e() raises an
> exception, but even more that e_raise() points to
> if not MY_GLOBAL Is the problem not really when I assign?
>
> My assumption is that some reordering is happening behind the scenes
> that creates a situation similar to the += which assigns hence expects
> to be at the local level.

The determination of whether a name is a reference to a local or  
global variable is made at compile time.  When a function contains a  
single assignment (or augmented assignment) to a name, the compiler  
generates bytecode such that all references to that name within the  
function will be looked up in the local scope only, including those  
before the assignment statement.

-Miles



From pfeldman at verizon.net  Wed Jul 15 14:19:18 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Wed, 15 Jul 2009 11:19:18 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
	<0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>
Message-ID: <24503248.post@talk.nabble.com>


I did initially ask for an infix xor operator, but eventually gave up on
this.  I like the first of your two one-line solutions below; this is clean
and easy to understand.  Thanks!  I'd still like to be able to write an
expression like '(a and b) xor (c and d) xor (e and f)', but it looks as
though that can't be done.



<snip>

Well, that's not exactly what you originally asked for.  But it's
still a one-liner:

def xor(*args): return bool(sum(map(bool, args)) % 2)

or perhaps

def xor(*args): return bool(len(filter(None, args)) & 1)
-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24503248.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From milesck at umich.edu  Wed Jul 15 14:24:23 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 14:24:23 -0400
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <m2prc3dlfo.fsf@valheru.db3l.homeip.net>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<m2prc3dlfo.fsf@valheru.db3l.homeip.net>
Message-ID: <B6A1B5F7-BA59-4B8A-A039-7D1CF93CEF39@umich.edu>

On Jul 14, 2009, at 5:06 PM, David Bolen wrote:
> Are you sure?  It seems to restrict them in the same block, but not in
> the entire file.  At least I was able to use both space and tab
> indented blocks in the same file with Python 3.0 and 3.1.

It seems to me that, within an indented block, Python 3.1 requires  
that you are consistent in your use of indentation characters *for  
that indentation level*.  For example, the following code seems to be  
allowed:

def foo():
<TAB>if True:
<TAB><SP><SP>x = 1
<TAB>else:
<TAB><TAB>x = 2
<TAB>return x

But replacing any of the first tabs on each line with 8 spaces  
(without replacing them all), which previously would have been  
allowed, is now an error.

-Miles



From wbrehaut at mcsnet.ca  Wed Jul 15 14:29:54 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 12:29:54 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>

On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson
<dickinsm at gmail.com> wrote:

>On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
>wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
>> have an 'xor' operator as well.
>
>Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
>that it's sufficiently useful to justify adding a new keyword 'xor' to
>the language;  I suspect that would be an uphill struggle. :)
>
>I'll just note that:
>
>(1) It's easy to emulate xor:  'x xor y' <-> bool(x) != bool(y)
>
>(2) 'and' and 'or' are special in that they have useful short-
>circuiting behaviour; xor doesn't have this property (that is, you
>always need to evaluate *both* operands to determine the result).
>
>I'd also guess that 'xor' would be much less used than 'and' or 'or',
>but maybe that's just a reflection of the sort of code that I tend to
>write.

You're right about that!. It's used everywhere in:

- coding and encryption theory (and practice) (e.g.,
http://www.mathcs.emory.edu/~whalen/Hash/Hash_Articles/IEEE/XOR-based%20hash%20functions.pdf)
- emulation and simulation of hardware (since all but the most trivial
logic circuits are likely to include XOR-gates)
- hence, for design of new architectures or simulators or virtual
machines and simplification of existing ones--(e.g.,
http://www.date-conference.com/archive/conference/proceedings/PAPERS/1999/DATE99/PDFFILES/05A_6.PDF)
and
http://bochs.sourceforge.net/Virtualization_Without_Hardware_Final.pdf
which includes:

"The answer relies on the observation that subtracting an integer
value from 0xFFFFFFFF gives the same result as XOR-ing that same value
to 0xFFFFFFFF."

And, perhaps the most useful use of all, for Bouton's solution of the
game of Nim--both for the proof that his strategy "solves" the game
and for an easy implementation of a Nim-playing program--and the only
operator needed is XOR (e.g., http://www.wordiq.com/definition/Nim).

wayne


From gerard.blais at gmail.com  Wed Jul 15 14:40:32 2009
From: gerard.blais at gmail.com (MCIPERF)
Date: Wed, 15 Jul 2009 11:40:32 -0700 (PDT)
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
	<n8m5m.3759$ze1.2493@news-server.bigpond.net.au>
	<mailman.2920.1247182102.8015.python-list@python.org>
Message-ID: <a27f8bda-55bd-4d71-87ff-af6ac07fcd75@r24g2000vbn.googlegroups.com>

On Jul 9, 7:28?pm, Miles Kaufmann <mile... at umich.edu> wrote:
> On Jul 9, 2009, at 9:20 AM, Lie Ryan wrote:
>
> > Michael Mossey wrote:
> >> I want to understand better what the "secret" is to responding to a
> >> ctrl-C in any shape or form.
>
> > Are you asking: "when would the python interpreter process
> > KeyboardInterrupt?"
> > ...
> > In single threaded python program, the currently running thread is
> > always the main thread (which can handle KeyboardInterrupt). I believe
> > SIGINT is checked at every ticks. But SIGINT cannot interrupt atomic
> > operations (i.e. it cannot interrupt long operations that takes a ?
> > single
> > tick).
>
> Some otherwise atomic single-bytecode operations (like large integer ?
> arithmetic) do manual checks for whether signals were raised (though ?
> that won't help at all if the operation isn't on the main thread).
>
> > I believe a tick in python is equivalent to a single bytecode, but
> > please correct me if I'm wrong.
>
> Not all opcodes qualify as a tick. ?In general, those opcodes that ?
> cause control to remain in the eval loop (and not make calls to other ?
> Python or C functions) don't qualify as ticks (but there are ?
> exceptions, e.g. so that while True: pass is interruptible). ?In ?
> Python/ceval.c: PyEval_EvalFrameEx(), those opcodes that don't end in ?
> goto fast_next_opcode are ticks.
>
> Please correct me if _I'm_ wrong! :)
> -Miles

You don't need to do I/O.

This works:

try:
   process_forever()
except KeyboardInterrupt:
   save critical stuff
   write nice messages

I often wrap a large computational task like this, with the idea that
the exception can let me exit safely, in my case by writing restart
parameters and printing a summary pf progress to date.

Gerry


From amrita at iisermohali.ac.in  Wed Jul 15 14:46:29 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Thu, 16 Jul 2009 00:16:29 +0530 (IST)
Subject: mail
Message-ID: <7683.210.212.36.65.1247683589.squirrel@www.iisermohali.ac.in>


Dear all,

Sorry that I am disturbing you all again and again but this is the way I
am trying to solve my problem:---

>>> import re
>>> exp = re.compile("CA")
>>> infile = open("file1.txt")
>>> for line in infile:
...     values = re.split("\s+", line)
...     if exp.search(line):
...        print ("%s %s CA = %s" %(values[2], values[3], values[6]))
...
 with this it is giving the output like:----

8 ALA CA = 54.67
15 ALA CA = 52.18
21 ALA CA = 54.33
23 ALA CA = 55.84
33 ALA CA = 55.58
38 ALA CA = 54.33

which is all right but i want CB and C value also in each row and it
should take value from 5th column infront of them, file is something
lookin like:-----

 47     8   ALA       H     H      7.85     0.02     1
 48     8   ALA       HA    H      2.98     0.02     1
 49     8   ALA       HB    H      1.05     0.02     1
 50     8   ALA       C     C    179.39      0.3     1
 51     8   ALA       CA    C     54.67      0.3     1
 52     8   ALA       CB    C     18.85      0.3     1
 53     8   ALA       N     N    123.95      0.3     1
107    15   ALA       H     H      8.05     0.02     1
108    15   ALA       HA    H      4.52     0.02     1
109    15   ALA       HB    H      1.29     0.02     1
110    15   ALA       C     C    177.18      0.3     1
111    15   ALA       CA    C     52.18      0.3     1
112    15   ALA       CB    C     20.64      0.3     1
113    15   ALA       N     N    119.31      0.3     1
154    21   ALA       H     H      7.66     0.02     1
155    21   ALA       HA    H      4.05     0.02     1
156    21   ALA       HB    H      1.39     0.02     1
157    21   ALA       C     C    179.35      0.3     1
158    21   ALA       CA    C     54.33      0.3     1
159    21   ALA       CB    C     17.87      0.3     1
160    21   ALA       N     N    123.58      0.3     1
169    23   ALA       H     H      8.78     0.02     1
170    23   ALA       HA    H      4.14     0.02     1
171    23   ALA       HB    H      1.62     0.02     1
172    23   ALA       C     C    179.93      0.3     1
173    23   ALA       CA    C     55.84      0.3     1
174    23   ALA       CB    C     17.55      0.3     1
175    23   ALA       N     N    120.16      0.3     1
232    33   ALA       H     H      7.57     0.02     1
233    33   ALA       HA    H      3.89     0.02     1
234    33   ALA       HB    H      1.78     0.02     1
235    33   ALA       C     C    179.24      0.3     1
236    33   ALA       CA    C     55.58      0.3     1
237    33   ALA       CB    C     19.75      0.3     1
238    33   ALA       N     N    121.52      0.3     1
269    38   ALA       H     H      8.29     0.02     1
270    38   ALA       HA    H      4.04     0.02     1
271    38   ALA       HB    H      1.35     0.02     1
272    38   ALA       C     C    178.95      0.3     1
273    38   ALA       CA    C     54.33      0.3     1
274    38   ALA       CB    C     18.30      0.3     1
275    38   ALA       N     N    120.62      0.3     1

I just want that it will give output something like:-----

8  ALA  C = 179.39  CA = 54.67  CB = 18.85
15 ALA  C = 177.18  CA = 52.18  CB = 20.64
21 ALA  C = 179.35  CA = 54.33  CB = 17.87.....

so first it will write the position of the amino acid(given by second
column)then amino acid here it is ALA and then the corresponding value of
C, CA and CB from 5th colum for each position of ALA.




Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From robert.kern at gmail.com  Wed Jul 15 14:47:28 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 15 Jul 2009 13:47:28 -0500
Subject: missing 'xor' Boolean operator
In-Reply-To: <tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
Message-ID: <h3l881$h4b$1@ger.gmane.org>

On 2009-07-15 13:29, Wayne Brehaut wrote:
> On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson
> <dickinsm at gmail.com>  wrote:
>
>> On Jul 14, 7:25 pm, "Dr. Phillip M. Feldman"<pfeld... at verizon.net>
>> wrote:
>>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice to
>>> have an 'xor' operator as well.
>> Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
>> that it's sufficiently useful to justify adding a new keyword 'xor' to
>> the language;  I suspect that would be an uphill struggle. :)
>>
>> I'll just note that:
>>
>> (1) It's easy to emulate xor:  'x xor y'<->  bool(x) != bool(y)
>>
>> (2) 'and' and 'or' are special in that they have useful short-
>> circuiting behaviour; xor doesn't have this property (that is, you
>> always need to evaluate *both* operands to determine the result).
>>
>> I'd also guess that 'xor' would be much less used than 'and' or 'or',
>> but maybe that's just a reflection of the sort of code that I tend to
>> write.
>
> You're right about that!. It's used everywhere in:
>
> - coding and encryption theory (and practice) (e.g.,
> http://www.mathcs.emory.edu/~whalen/Hash/Hash_Articles/IEEE/XOR-based%20hash%20functions.pdf)
> - emulation and simulation of hardware (since all but the most trivial
> logic circuits are likely to include XOR-gates)
> - hence, for design of new architectures or simulators or virtual
> machines and simplification of existing ones--(e.g.,
> http://www.date-conference.com/archive/conference/proceedings/PAPERS/1999/DATE99/PDFFILES/05A_6.PDF)
> and
> http://bochs.sourceforge.net/Virtualization_Without_Hardware_Final.pdf
> which includes:
>
> "The answer relies on the observation that subtracting an integer
> value from 0xFFFFFFFF gives the same result as XOR-ing that same value
> to 0xFFFFFFFF."
>
> And, perhaps the most useful use of all, for Bouton's solution of the
> game of Nim--both for the proof that his strategy "solves" the game
> and for an easy implementation of a Nim-playing program--and the only
> operator needed is XOR (e.g., http://www.wordiq.com/definition/Nim).

All of those can use the bitwise XOR operator, not the boolean XOR. Python 
already has the ^ operator for those purposes.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dickinsm at gmail.com  Wed Jul 15 14:51:44 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Wed, 15 Jul 2009 11:51:44 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
Message-ID: <d5c62721-6d07-415f-b2de-150584504608@i6g2000yqj.googlegroups.com>

On Jul 15, 7:29?pm, Wayne Brehaut <wbreh... at mcsnet.ca> wrote:
> On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson <dicki... at gmail.com> wrote:
> >I'd also guess that 'xor' would be much less used than 'and' or 'or',
> >but maybe that's just a reflection of the sort of code that I tend to
> >write.
>
> You're right about that!. It's used everywhere in:
> [snip examples and references]

Those examples are (almost) all about the *bitwise* xor operator,
which exists in Python ('^') and, as you point out, has no shortage of
good uses.  The discussion was about a *logical* xor, to parallel the
existing 'and' and 'or' operators.

--
Mark


From anthony.tolle at gmail.com  Wed Jul 15 14:53:23 2009
From: anthony.tolle at gmail.com (Anthony Tolle)
Date: Wed, 15 Jul 2009 11:53:23 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
Message-ID: <ae7da03e-5852-4dbe-b11c-37f4afc32dbe@n11g2000yqb.googlegroups.com>

On Jul 14, 2:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
> have an 'xor' operator as well.

My $0.02 on this discussion: There would be nothing gained by having
non-bitwise XOR operator.  You can't short-circuit XOR, because you
must evaluate all operands to produce a result.  Consequently,
returning the "true" item also doesn't make much sense.  XOR is closer
to the the logical NOT operator than it is to AND or OR.

Here's my own take on a function that can handle any number of
arguments (it should probably raise an exception for 0 or 1 arguments,
but I'm lazy):

def xor(*operands):
    if operands:
        operands = list(operands)
        a = bool(operands.pop(0))
        while operands:
            b = bool(operands.pop(0))
            if a:
                if b:
                    a = False
            elif b:
                a = True
        return a
    return False


From jeanmichel at sequans.com  Wed Jul 15 15:05:16 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 21:05:16 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
Message-ID: <4A5E286C.5060607@sequans.com>

Miles Kaufmann wrote:
>
> On Jul 15, 2009, at 1:43 PM, Jean-Michel Pichavant wrote:
>
>> Hrvoje Niksic wrote:
>> [snip]
>>> Note that in Python A or B is in fact not equivalent to not(not A and
>>> not B).
>>>
>> >>> l = [(True, True), (True, False), (False, True), (False, False)]
>> >>> for p in l:
>> ...     p[0] or p[1]
>> [snip]
>> Did I make twice the same obvious error ?
>
>
> Try again with:
>
> l = [('foo','bar'), ('foo', ''), ('', 'bar'), ('', '')]
>
> -Miles
>
Didn't know that.
So if I resume:
- not 'foo' => False
- 'foo' or 'foo' => 'foo'

I may be missing something, but honestly, Guido must have smoked some 
heavy stuff to write such logic, has he ?

Let's play again
False or 'foo' => 'foo'
False and 'foo' => False

So funny. I would have expected boolean operators to return a boolean 
value. I should have read the f*** manual (this is an anticipated RTFM 
counter-attack). Anyway Miles, thanks for the update.

JM



From invalid at invalid  Wed Jul 15 15:05:30 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 15 Jul 2009 14:05:30 -0500
Subject: mail
References: <mailman.3184.1247683595.8015.python-list@python.org>
Message-ID: <zeydnTuRPNnntcPXnZ2dnUVZ_t6dnZ2d@posted.visi>

On 2009-07-15, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:

> Sorry that I am disturbing you all again and again but this is the way I
> am trying to solve my problem:---

We could probably be a lot more helpful if you would keep these
postings all in a single thread so that people who didn't read
the first postings knew what you were talking about in
subsequent postings.


>>>> import re
>>>> exp = re.compile("CA")

> [...]
>
> file is something lookin like:-----
>
>  47     8   ALA       H     H      7.85     0.02     1

[...]

IMO you're making a mistake using the "re" module for this
task.  I think you'd be a lot better off if you just used the
string type's split method to split each line up into fields
and processed the individual fields:

  for line in inputfile:
  
      field = line.split()

      if field[2] == "CA":
         <<do whatever with whichever fields you care about>>
      elif field[2] == "soemthing-else"
         <<do something else with some other fields>>      

  <<print results of doing whatever and something else above>>

-- 
Grant Edwards                   grante             Yow! If I felt any more
                                  at               SOPHISTICATED I would DIE
                               visi.com            of EMBARRASSMENT!


From jcd at sdf.lonestar.org  Wed Jul 15 15:40:36 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Wed, 15 Jul 2009 15:40:36 -0400
Subject: mail
In-Reply-To: <7683.210.212.36.65.1247683589.squirrel@www.iisermohali.ac.in>
References: <7683.210.212.36.65.1247683589.squirrel@www.iisermohali.ac.in>
Message-ID: <1247686836.11677.196.camel@aalcdl07>

On Thu, 2009-07-16 at 00:16 +0530, amrita at iisermohali.ac.in wrote:
> Dear all,
> 
> Sorry that I am disturbing you all again and again but this is the way I
> am trying to solve my problem:---
> 
> >>> import re
> >>> exp = re.compile("CA")
> >>> infile = open("file1.txt")
> >>> for line in infile:
> ...     values = re.split("\s+", line)
> ...     if exp.search(line):
> ...        print ("%s %s CA = %s" %(values[2], values[3], values[6]))
> ...
>  with this it is giving the output like:----
> 
> 8 ALA CA = 54.67
> 15 ALA CA = 52.18
> 21 ALA CA = 54.33
> 23 ALA CA = 55.84
> 33 ALA CA = 55.58
> 38 ALA CA = 54.33
> 
> which is all right but i want CB and C value also in each row and it
> should take value from 5th column infront of them, file is something
> lookin like:-----
> 
>  47     8   ALA       H     H      7.85     0.02     1
>  48     8   ALA       HA    H      2.98     0.02     1
>  49     8   ALA       HB    H      1.05     0.02     1
>  50     8   ALA       C     C    179.39      0.3     1
>  51     8   ALA       CA    C     54.67      0.3     1
>  52     8   ALA       CB    C     18.85      0.3     1
>  53     8   ALA       N     N    123.95      0.3     1
> 107    15   ALA       H     H      8.05     0.02     1
> 108    15   ALA       HA    H      4.52     0.02     1
> 109    15   ALA       HB    H      1.29     0.02     1
> 110    15   ALA       C     C    177.18      0.3     1
> 111    15   ALA       CA    C     52.18      0.3     1
> 112    15   ALA       CB    C     20.64      0.3     1
> 113    15   ALA       N     N    119.31      0.3     1
> 154    21   ALA       H     H      7.66     0.02     1
> 155    21   ALA       HA    H      4.05     0.02     1
> 156    21   ALA       HB    H      1.39     0.02     1
> 157    21   ALA       C     C    179.35      0.3     1
> 158    21   ALA       CA    C     54.33      0.3     1
> 159    21   ALA       CB    C     17.87      0.3     1
> 160    21   ALA       N     N    123.58      0.3     1
> 169    23   ALA       H     H      8.78     0.02     1
> 170    23   ALA       HA    H      4.14     0.02     1
> 171    23   ALA       HB    H      1.62     0.02     1
> 172    23   ALA       C     C    179.93      0.3     1
> 173    23   ALA       CA    C     55.84      0.3     1
> 174    23   ALA       CB    C     17.55      0.3     1
> 175    23   ALA       N     N    120.16      0.3     1
> 232    33   ALA       H     H      7.57     0.02     1
> 233    33   ALA       HA    H      3.89     0.02     1
> 234    33   ALA       HB    H      1.78     0.02     1
> 235    33   ALA       C     C    179.24      0.3     1
> 236    33   ALA       CA    C     55.58      0.3     1
> 237    33   ALA       CB    C     19.75      0.3     1
> 238    33   ALA       N     N    121.52      0.3     1
> 269    38   ALA       H     H      8.29     0.02     1
> 270    38   ALA       HA    H      4.04     0.02     1
> 271    38   ALA       HB    H      1.35     0.02     1
> 272    38   ALA       C     C    178.95      0.3     1
> 273    38   ALA       CA    C     54.33      0.3     1
> 274    38   ALA       CB    C     18.30      0.3     1
> 275    38   ALA       N     N    120.62      0.3     1
> 
> I just want that it will give output something like:-----
> 
> 8  ALA  C = 179.39  CA = 54.67  CB = 18.85
> 15 ALA  C = 177.18  CA = 52.18  CB = 20.64
> 21 ALA  C = 179.35  CA = 54.33  CB = 17.87.....
> 
> so first it will write the position of the amino acid(given by second
> column)then amino acid here it is ALA and then the corresponding value of
> C, CA and CB from 5th colum for each position of ALA.
> 

Your program is structured wrong for doing what you want.  Right now you
are essentially saying, "for each line in the input file, print
something", but each line of the input file only has part of the
information you want.  Instead, you should create a data structure that
gathers the pieces you want, and only print once you have all of those
pieces in place.

Step one, create your data structure, so the data is grouped the way you
want it, not by line:

>>> thingies = {} # create a dictionary
>>> for line in infile:
>>>     data = line.split()
>>>
>>>     if data[1] not in thingies:
>>>         # group data by data[1]
>>>         thingies[data[1]] = {}
>>> 
>>>     thingies[data[1]][data[3]] = data[5]

Step two, extract the data from the list:

>>> for key, data in thingies.items(): 
>>>     print key,
>>>     for entry in data
>>>     print '%s = %s' % (entry, data[entry]),

This should do what you want, minus some formatting issues.

Cheers,
Cliff




From stefan_ml at behnel.de  Wed Jul 15 15:48:13 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Wed, 15 Jul 2009 21:48:13 +0200
Subject: compiling python
In-Reply-To: <mailman.3123.1247616711.8015.python-list@python.org>
References: <mailman.3123.1247616711.8015.python-list@python.org>
Message-ID: <4a5e327d$0$31339$9b4e6d93@newsspool4.arcor-online.net>

Mag Gam wrote:
> At my university we are trying to compile python with --enable-shared

Is there a reason why you need to compile the CPython interpreter yourself?


> however when I do a make many things fail. Is it a good idea to
> compile python with shared libraries?

Perfectly fine, Linux distros do that by default, for example.

"many things fail" is not a very detailed problem description, though.
Could you state more exactly what you do and provide the error messages
that you see?

Stefan


From wbrehaut at mcsnet.ca  Wed Jul 15 15:55:08 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 13:55:08 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
	<d5c62721-6d07-415f-b2de-150584504608@i6g2000yqj.googlegroups.com>
Message-ID: <qtbs55hf9u1f2uql70ea9576caelk1q63u@4ax.com>

On Wed, 15 Jul 2009 11:51:44 -0700 (PDT), Mark Dickinson
<dickinsm at gmail.com> wrote:

>On Jul 15, 7:29?pm, Wayne Brehaut <wbreh... at mcsnet.ca> wrote:
>> On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson <dicki... at gmail.com> wrote:
>> >I'd also guess that 'xor' would be much less used than 'and' or 'or',
>> >but maybe that's just a reflection of the sort of code that I tend to
>> >write.
>>
>> You're right about that!. It's used everywhere in:
>> [snip examples and references]
>
>Those examples are (almost) all about the *bitwise* xor operator,
>which exists in Python ('^') and, as you point out, has no shortage of
>good uses.  The discussion was about a *logical* xor, to parallel the
>existing 'and' and 'or' operators.

I thought you were saying your program domains didn't include a lot of
requirements for xor in general, rather than just no uses for Boolean
xor--and I'm used to thinking of xor on binary vectors as "Boolean"
anyway so would still have been confused.

The most common non-binary-bit-wise xor is the general "symmetric
difference" of sets, most likely to be useful in list or dictionary
processing or database-like contexts. Please see my suggested use-case
for Steven below.

wayne


From miheavner at gmail.com  Wed Jul 15 15:55:56 2009
From: miheavner at gmail.com (mheavner)
Date: Wed, 15 Jul 2009 12:55:56 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
Message-ID: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>

I'm using multiprocessing to spawn several subprocesses, each of which
uses a very large data structure (making it impractical to pass it via
pipes / pickling). I need to allocate this structure once when the
process is created and have it remain in memory for the duration of
the process. The way the multiprocessing module is set up, only the
'run' method runs within the subprocess - so creating a wrapper class
with a constructor that allocates the structure in __init__ will not
work, as far as I know, as this will still be within the parent
process.

If I were working in C/C++, I would declare the variable "static"
within the function body - is there any way with the multiprocessing
module to have persistent data members within subprocesses?

Any ideas??

Thanks,
   Matt


From drozzy at gmail.com  Wed Jul 15 16:00:06 2009
From: drozzy at gmail.com (drozzy)
Date: Wed, 15 Jul 2009 13:00:06 -0700 (PDT)
Subject: Reading a large csv file
References: <1cbd6f830906222017m694bc738m40a46e2851381e@mail.gmail.com> 
	<b78ad4bc0906222128h42d498b0xbfa29684391fa1d4@mail.gmail.com> 
	<1cbd6f830906222227q7ec2a89ke3d4805c9ace80e8@mail.gmail.com> 
	<h1pv45$l7h$1@ger.gmane.org> <4A41D1FD.7080004@simplistix.co.uk> 
	<mailman.2048.1245843498.8015.python-list@python.org>
	<pyv0m.524$ze1.126@news-server.bigpond.net.au> 
	<mailman.2155.1246013561.8015.python-list@python.org>
Message-ID: <c4382879-c75b-47e8-b05b-073cba6b90df@l32g2000vbp.googlegroups.com>

On Jun 26, 6:47?am, Mag Gam <magaw... at gmail.com> wrote:
> Thankyou everyone for the responses! I took some of your suggestions
> and my loading sped up by 25%

what a useless post...


From hniksic at xemacs.org  Wed Jul 15 16:00:52 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Wed, 15 Jul 2009 22:00:52 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<mailman.3174.1247679810.8015.python-list@python.org>
Message-ID: <87bpnliumj.fsf@busola.homelinux.net>

Jean-Michel Pichavant <jeanmichel at sequans.com> writes:

> Hrvoje Niksic wrote:
> [snip]
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>>   
>>>> l = [(True, True), (True, False), (False, True), (False, False)]
>>>> for p in l:
> ...     p[0] or p[1]
[...]

Try with a different data set, for example:

>>> 10 or 20
10
>>> not(not 10 and not 20)
True


From deets at nospam.web.de  Wed Jul 15 16:22:46 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 22:22:46 +0200
Subject: Persistent variable in subprocess using multiprocessing?
In-Reply-To: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
Message-ID: <7c6s4nF25vs08U1@mid.uni-berlin.de>

mheavner schrieb:
> I'm using multiprocessing to spawn several subprocesses, each of which
> uses a very large data structure (making it impractical to pass it via
> pipes / pickling). I need to allocate this structure once when the
> process is created and have it remain in memory for the duration of
> the process. The way the multiprocessing module is set up, only the
> 'run' method runs within the subprocess - so creating a wrapper class
> with a constructor that allocates the structure in __init__ will not
> work, as far as I know, as this will still be within the parent
> process.
> 
> If I were working in C/C++, I would declare the variable "static"
> within the function body - is there any way with the multiprocessing
> module to have persistent data members within subprocesses?

Works for me, at least under OSX (and I presume *nixes in general work.) 
No idea about Windows.


The thing to keep in mind is that forking is used, and that 
interpreter-state up to the moment of the fork is the same for all 
subprocesses.



from multiprocessing import Process

class MyProcess(Process):


     def __init__(self, huge_shared_state):
         self.huge_shared_state = huge_shared_state
         super(MyProcess, self).__init__()


     def run(self):
         print self.name, len(self.huge_shared_state)




shared_state = range(1000000)

processes = []
for i in xrange(10):
     p = MyProcess(shared_state)
     p.start()
     processes.append(p)


for p in processes:
     p.join()



Diez


From db3l.net at gmail.com  Wed Jul 15 16:26:17 2009
From: db3l.net at gmail.com (David Bolen)
Date: Wed, 15 Jul 2009 16:26:17 -0400
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<m2prc3dlfo.fsf@valheru.db3l.homeip.net>
	<mailman.3183.1247682273.8015.python-list@python.org>
Message-ID: <m2hbxdelqu.fsf@valheru.db3l.homeip.net>

Miles Kaufmann <milesck at umich.edu> writes:

> On Jul 14, 2009, at 5:06 PM, David Bolen wrote:
>> Are you sure?  It seems to restrict them in the same block, but not in
>> the entire file.  At least I was able to use both space and tab
>> indented blocks in the same file with Python 3.0 and 3.1.
>
> It seems to me that, within an indented block, Python 3.1 requires
> that you are consistent in your use of indentation characters *for
> that indentation level*.  For example, the following code seems to be
> allowed:

Um, right - in other words, what I said :-)

-- David


From rodriguealcazar at gmail.com  Wed Jul 15 16:27:11 2009
From: rodriguealcazar at gmail.com (Rodrigue)
Date: Wed, 15 Jul 2009 13:27:11 -0700 (PDT)
Subject: python first assignment of a global variable
References: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
	<mailman.3181.1247681857.8015.python-list@python.org>
Message-ID: <47c62f6f-cf9a-4f74-ad71-5f2eccc8c797@h2g2000yqg.googlegroups.com>

> MY_GLOBAL, by virtue of being assigned to later in the function, and the
> absence of a global statement, is identified as a local variable.

> When a function contains a
> single assignment (or augmented assignment) to a name, the compiler
> generates bytecode such that all references to that name within the
> function will be looked up in the local scope only

Alright. I didn't know that. I thought the entire scope (local, then
global) was considered in every situation. It does explain the
observed behaviour then.

I'm surprised I never bumped into that before, but I'm glad I learnt
something new about python today.

Thanks Emile and Miles for the explanation!


From georgeoliverGO at gmail.com  Wed Jul 15 16:39:37 2009
From: georgeoliverGO at gmail.com (George Oliver)
Date: Wed, 15 Jul 2009 13:39:37 -0700 (PDT)
Subject: interactive fiction in Python?
Message-ID: <5c97224b-99d4-469b-90cb-1c04b1e1e9a0@m11g2000yqh.googlegroups.com>

hi, I'm just curious who might be working on interactive fiction
modules in the style of Inform or TADS for Python. I've seen a few
threads on this list [1] (among many that mention IF tangentially),
and there are old projects like PUB and PAWS. There are some newer
potential projects such as Curveship as well. In any case I'd like to
see what's out there.


thanks, George


[1]:

http://bit.ly/Python_Text_Adventure_Authoring_System

http://bit.ly/simple_interactive_fiction_engine

http://bit.ly/adventure_engines_in_Python


From perfreem at gmail.com  Wed Jul 15 16:54:02 2009
From: perfreem at gmail.com (per)
Date: Wed, 15 Jul 2009 13:54:02 -0700 (PDT)
Subject: allowing output of code that is unittested?
Message-ID: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>

hi all,

i am using the standard unittest module to unit test my code. my code
contains several print statements which i noticed are repressed when i
call my unit tests using:

if __name__ == '__main__':
    suite = unittest.TestLoader().loadTestsFromTestCase(TestMyCode)
    unittest.TextTestRunner(verbosity=2).run(suite)

is there a way to allow all the print statements in the code that is
being run by the unit test functions to be printed to stdio?  i want
to be able to see the output of the tested code, in addition to the
output of the unit testing framework.

thank you.


From jkn_gg at nicorp.f9.co.uk  Wed Jul 15 17:25:24 2009
From: jkn_gg at nicorp.f9.co.uk (jkn)
Date: Wed, 15 Jul 2009 14:25:24 -0700 (PDT)
Subject: Ann: Google releases Python-based open-source NX server
Message-ID: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>

Google quietly releases open-source NX server ...written in Python,
apparently

<http://www.computerworld.com/s/article/9135504/
Google_quietly_releases_open_source_NX_server?taxonomyId=88>

Neatx can be downloaded from Google's code repository:

<http://code.google.com/p/neatx/>

    Regards
    J^n



From magobin at gmail.com  Wed Jul 15 17:26:53 2009
From: magobin at gmail.com (Alex)
Date: Wed, 15 Jul 2009 14:26:53 -0700 (PDT)
Subject: How to Force exiting from program/script
Message-ID: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>

hi at all,
 I have made a script with a while loop and I want that after 30
seconds the program stop and exit . But the code like this doesn't
run:
In the Console I can see work so that function is correctly called...

#Function to exit
def exit():
    print "work"
    raise SystemExit()
t = threading.Timer(30.0, exit)
t.start()

# Loop
while True:
...many lines....



From deets at nospam.web.de  Wed Jul 15 17:39:01 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 23:39:01 +0200
Subject: How to Force exiting from program/script
In-Reply-To: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>
References: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>
Message-ID: <7c70jlF25pt2sU1@mid.uni-berlin.de>

Alex schrieb:
> hi at all,
>  I have made a script with a while loop and I want that after 30
> seconds the program stop and exit . But the code like this doesn't
> run:
> In the Console I can see work so that function is correctly called...
> 
> #Function to exit
> def exit():
>     print "work"
>     raise SystemExit()
> t = threading.Timer(30.0, exit)
> t.start()
> 
> # Loop
> while True:
> ...many lines....
> 

This works for me:

import threading
import time

def work():
     while True:
         pass



t = threading.Thread(target=work)
t.setDaemon(True)
t.start()

time.sleep(10)
raise SystemExit


The trick is to raise the SystemExit in the main-thread.

Diez


From deets at nospam.web.de  Wed Jul 15 17:46:52 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 23:46:52 +0200
Subject: allowing output of code that is unittested?
In-Reply-To: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>
References: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>
Message-ID: <7c712cF26q447U1@mid.uni-berlin.de>

per schrieb:
> hi all,
> 
> i am using the standard unittest module to unit test my code. my code
> contains several print statements which i noticed are repressed when i
> call my unit tests using:
> 
> if __name__ == '__main__':
>     suite = unittest.TestLoader().loadTestsFromTestCase(TestMyCode)
>     unittest.TextTestRunner(verbosity=2).run(suite)
> 
> is there a way to allow all the print statements in the code that is
> being run by the unit test functions to be printed to stdio?  i want
> to be able to see the output of the tested code, in addition to the
> output of the unit testing framework.


I use nosetests to discover & run tests, and that has an "-s"-option 
that does exactly that.

Diez


From mobiledreamers at gmail.com  Wed Jul 15 18:01:15 2009
From: mobiledreamers at gmail.com (mobiledreamers at gmail.com)
Date: Wed, 15 Jul 2009 15:01:15 -0700
Subject: Ann: Google releases Python-based open-source NX server
In-Reply-To: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
Message-ID: <c1870d60907151501i651a0ea8m11e03cd02624bcce@mail.gmail.com>

On Wed, Jul 15, 2009 at 2:25 PM, jkn <jkn_gg at nicorp.f9.co.uk> wrote:

> Google quietly releases open-source NX server ...written in Python,
> apparently
>
> <http://www.computerworld.com/s/article/9135504/
> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>
> Neatx can be downloaded from Google's code repository:
>
> <http://code.google.com/p/neatx/>
>
>    Regards
>    J^n
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Bidegg worlds best auction site
http://bidegg.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090715/a9bbf062/attachment.html>

From nobody at nowhere.com  Wed Jul 15 18:31:38 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 15 Jul 2009 23:31:38 +0100
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
	<pan.2009.07.11.06.24.02.406000@nowhere.com>
	<mailman.3163.1247670223.8015.python-list@python.org>
Message-ID: <pan.2009.07.15.22.31.38.0@nowhere.com>

On Wed, 15 Jul 2009 17:03:30 +0200, Jean-Michel Pichavant wrote:

>> Hard-coding control/escape sequences is just lame. Use the curses modules
>> to obtain the correct sequences for the terminal.
>>
>>   
> As the OP I'm really interested in doing so. I currently have all my 
> colors hard-coded.
> Now It may be lame but as soon as I call curses.initscr(), it's just 
> messing up with my terminal,

Use curses.setupterm() to locate and parse the terminfo/termcap entry
without entering "curses mode". Most curses functions won't work without
calling initscr(), but the terminfo functions will.

> moreover I didn't figure out how to "print  
> 'hello'" using curses color codes.
> Anyone has an example ? I'm pretty sure it may fit in one line.

#!/usr/bin/env python
import curses
curses.setupterm()
setaf = curses.tigetstr('setaf')
if not setaf:
    setaf = ''
print (curses.tparm(setaf,1) + "hello, " +
	curses.tparm(setaf,2) + "world" +
	curses.tparm(setaf,0))




From mmanns at gmx.net  Wed Jul 15 18:36:51 2009
From: mmanns at gmx.net (mmanns at gmx.net)
Date: Thu, 16 Jul 2009 00:36:51 +0200
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
	<e038b7f1-400f-43c7-85bc-df81170353c0@r34g2000vba.googlegroups.com>
Message-ID: <20090716003651.09bca73c@Knock>

On Sat, 11 Jul 2009 15:33:32 -0700 (PDT)
Daniel Platz <mail.to.daniel.platz at googlemail.com> wrote:

> thanks for your repleys. I have tried matplotlib but it is extremely
> slow. I think it is more optimized for good looking plots instead of
> speed. I do not know the Python bindings of gnuplot and Veusz. To
> clarify the issue again, by 25000 data points I mean 25000 pixels,
> i.e. corresponding (x,y) pairs. Thus the mapping to one pixel on the
> screen is not unique.

Have you already tried out rpy?

Martin


From shai at platonix.com  Wed Jul 15 18:45:57 2009
From: shai at platonix.com (Shai)
Date: Wed, 15 Jul 2009 15:45:57 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<uOp5m.3783$ze1.731@news-server.bigpond.net.au>
	<42fbcee1-61b2-4ba8-a50a-39c9c0d2fe9c@k19g2000yqn.googlegroups.com>
Message-ID: <cbf0a92e-9e6d-4cd8-9c98-0ae9585cc282@y7g2000yqa.googlegroups.com>

Since nobody else mentioned this...

Python classes have a magic method called __del__ which is usually
called just before an object is garbage-collected. Further, Python
uses reference-counting to tell when an object is no longer
accessible. This means that if your resource classes define __del__
methods, these will be called properly when the object using them is
destroyed, and you don't need to write an explicit close() method for
this.

class Resource(object):
  def __init__(self, param):
    # acquire resource

  def __del__(self):
    # release resource

not_my_responsibility = Resource(1)

class Foo(object):
  def __init__(self):
     self.ref = not_my_responsibility # self.ref.__del__() will not be
called as long as the module exists
     local = Resource(2) # local.__del__() will be called as soon as
__init__ is exited
     self.held = Resource(3) # self.held.__del__() will be called when
the object dies
     z = 1/0 # The exception in the initializer will kill the object,
triggering some Resource.__del__() calls

There are two caveats:

1) __del__ methods prevent instances of your class from being
collected when they are involved in cyclical structures; this means if
your structures start to get complex (sometimes a doubly-linked list
is complex enough), you may find yourself leaking memory.

2) The bit about reference counting, which allows predictable
destruction, holds for CPython, but not for Jython, and IIRC also not
for IronPython (I don't know about PyPy or other implementations). It
is a feature of the reference implementation, not the language
definition.


From wbrehaut at mcsnet.ca  Wed Jul 15 18:54:00 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 16:54:00 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <7bns55dch1pler31ai2ivdp1u6nk60lnfo@4ax.com>

On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson
<dickinsm at gmail.com> wrote:

>On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
>wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
>> have an 'xor' operator as well.
>
>Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
>that it's sufficiently useful to justify adding a new keyword 'xor' to
>the language;  I suspect that would be an uphill struggle. :)

=== 8< ===
And for the objects for which it *is* sufficiently useful (sets) the
xor operator ^ is available:

>>> cheese = set(['cheddar', 'limburger', 'stilton'])
>>> stinky = set(['skunk', 'limburger', 'stilton', 'polecat', 'doggy-doo', 'civet'])
>>> nasty = set(['doggy-doo', 'polecat', 'limburger', 'Perl'])
>>> cheese & stinky # stinky cheese
set(['limburger', 'stilton'])
>>> cheese ^ stinky # either cheese or stinky but not both
set(['doggy-doo', 'civet', 'polecat', 'skunk', 'cheddar'])
>>> cheese ^ stinky ^ nasty # in an odd number of these sets (1 or 3)
set(['civet', 'cheddar', 'Perl', 'limburger', 'skunk'])

wayne


From wbrehaut at mcsnet.ca  Wed Jul 15 18:57:59 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 16:57:59 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <ipbs551ll266hf3p0v7anfqo86erisldrs@4ax.com>

On 15 Jul 2009 09:11:44 GMT, Steven D'Aprano
<steven at REMOVE.THIS.cybersource.com.au> wrote:

>On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
>
>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>> to have an 'xor' operator as well.
>
>I've often wished there was too, for the sake of completeness and 
>aesthetics, I'd love to be able to write:
>
>a xor b
>
>instead of defining a function xor(a, b).
>
>Unfortunately, outside of boolean algebra and simulating electrical 
>circuits, I can't think of any use-cases for an xor operator. Do you have 
>any?

Since xor in set theory is the symmetric difference,  perhaps we'd
like to know all items in exactly one of two word lists or
dictionaries, or anything else we could easily set-ize:

>>> cheese = set(['cheddar', 'limburger', 'stilton'])
>>> stinky = set(['skunk', 'limburger', 'stilton', 'polecat', 'doggy-doo', 'civet'])
>>> nasty = set(['doggy-doo', 'polecat', 'limburger', 'Perl'])
>>> cheese & stinky # stinky cheese
set(['limburger', 'stilton'])
>>> cheese ^ stinky # either cheese or stinky but not both
set(['doggy-doo', 'civet', 'polecat', 'skunk', 'cheddar'])
>>> cheese ^ stinky ^ nasty # in an odd number of these sets (1 or 3)
set(['civet', 'cheddar', 'Perl', 'limburger', 'skunk'])

Who hasn't needed that occasionally?

wayne


From nobody at nowhere.com  Wed Jul 15 19:01:37 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 00:01:37 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
Message-ID: <pan.2009.07.15.23.01.37.844000@nowhere.com>

On Wed, 15 Jul 2009 21:05:16 +0200, Jean-Michel Pichavant wrote:

> So if I resume:
> - not 'foo' => False
> - 'foo' or 'foo' => 'foo'
> 
> I may be missing something, but honestly, Guido must have smoked some 
> heavy stuff to write such logic, has he ?

Several languages (e.g. Lisp, Bourne shell) behave the same way, i.e. "or"
returns the first element which is considered true while "and" returns the
last element provided that all preceding elements are considered true.

> Let's play again
> False or 'foo' => 'foo'
> False and 'foo' => False
> 
> So funny. I would have expected boolean operators to return a boolean 
> value.

In Python, almost everything is a boolean value.

Compare with Lisp, where everything is a boolean value: nil (the empty
list) is false and everything else (including integer zero) is true.



From clp2 at rebertia.com  Wed Jul 15 19:02:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 16:02:13 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <ipbs551ll266hf3p0v7anfqo86erisldrs@4ax.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<ipbs551ll266hf3p0v7anfqo86erisldrs@4ax.com>
Message-ID: <50697b2c0907151602j393935eas4d5e18394baaa639@mail.gmail.com>

On Wed, Jul 15, 2009 at 3:57 PM, Wayne Brehaut<wbrehaut at mcsnet.ca> wrote:
> On 15 Jul 2009 09:11:44 GMT, Steven D'Aprano
> <steven at REMOVE.THIS.cybersource.com.au> wrote:
>
>>On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
>>
>>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice
>>> to have an 'xor' operator as well.
>>
>>I've often wished there was too, for the sake of completeness and
>>aesthetics, I'd love to be able to write:
>>
>>a xor b
>>
>>instead of defining a function xor(a, b).
>>
>>Unfortunately, outside of boolean algebra and simulating electrical
>>circuits, I can't think of any use-cases for an xor operator. Do you have
>>any?
>
> Since xor in set theory is the symmetric difference, ?perhaps we'd
> like to know all items in exactly one of two word lists or
> dictionaries, or anything else we could easily set-ize:
>
>>>> cheese = set(['cheddar', 'limburger', 'stilton'])
>>>> stinky = set(['skunk', 'limburger', 'stilton', 'polecat', 'doggy-doo', 'civet'])
>>>> nasty = set(['doggy-doo', 'polecat', 'limburger', 'Perl'])
>>>> cheese & stinky # stinky cheese
> set(['limburger', 'stilton'])
>>>> cheese ^ stinky # either cheese or stinky but not both
> set(['doggy-doo', 'civet', 'polecat', 'skunk', 'cheddar'])
>>>> cheese ^ stinky ^ nasty # in an odd number of these sets (1 or 3)
> set(['civet', 'cheddar', 'Perl', 'limburger', 'skunk'])
>
> Who hasn't needed that occasionally?

This discussion is about adding a *logical* operator for use in
boolean expressions. We obviously already have ^ for non-boolean use.

Cheers,
Chris
-- 
http://blog.rebertia.com


From pdlemper at earthlink.net  Wed Jul 15 20:07:18 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Wed, 15 Jul 2009 19:07:18 -0500
Subject: Can module tell if running from interpreter vs Windows command line ?
Message-ID: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>

The WConio console module produces different colors, sometimes quite
different, when run from Windows command line vs from Python
interpreter >>> .  A good foregnd/backgnd combination under one
may be unreadable under the other  : (
I'm using Python 3.0 with the corresponding WConio on XP.
Is there any way for the module to detect under which it has been 
started ?    Thanks


From pavlovevidence at gmail.com  Wed Jul 15 20:18:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 15 Jul 2009 17:18:52 -0700 (PDT)
Subject: import module unbelieveable behaviour
References: <mailman.3157.1247667587.8015.python-list@python.org>
Message-ID: <c134cd82-495a-4084-8929-f08ba435a2a7@i6g2000yqj.googlegroups.com>

On Jul 15, 6:12?am, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> Dear conference!
>
> I have test Why python based script for HeeksCNC post-processing does not
> work... ?And I've got unbelievable behavior ?When importing module module
> manually it works, but same opertaion from script does not
> ?work as seen
>
> /opt/HeeksCAD8/HeeksCNC> python
> Python 2.6 (r26:66714, Feb ?3 2009, 20:49:49)
> [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> Type "help", "copyright", "credits" or "license" for more information.>>> import nc.rez
>
> /opt/HeeksCAD8/HeeksCNC> python test.py
> Traceback (most recent call last):
> ? File "test.py", line 7, in <module>
> ? ? import nc.rez
> ImportError: No module named rez
>
> /opt/HeeksCAD8/HeeksCNC> python ./test.py
> Traceback (most recent call last):
> ? File "./test.py", line 7, in <module>
> ? ? import nc.rez
> ImportError: No module named rez
>
> Would anyone be helpful for me to get more information about this problem
> because ?pydb does not show anything usable for me,please?


That's a tricky one, indeed.

Here's my guess: test.py is a symlink to a file in another directory.

A major difference between interactive and script mode is the value of
sys.path[0], which is the directory Python uses for local modules and
packages.  Python uses the current directory when running in
interactive mode, but it uses the directory where the script is
located when it is called on a script.

Normally, when you run python on a script in the current directory,
the behavior is the same as interactive mode, because the directory
where the script is located is the current directory.  But there's the
gotcha: when you run python on symlinked file, Python sets sys.path[0]
to the directory containing the actual file, not the directory
containing the symlink.  Thus even if the symlink is in the current
directory, sys.path[0] is set to a different one.

As a workaround, test.py should explicitly add '' to sys.path:

sys.path.insert(0,'')


There is another notable difference in behavior between the two
modes.  In interactive mode, sys.path[0] is ''.  If you were to change
the current directory from within Python, using os.chdir(), then
future imports will occur relative to the new current directory.
However, if you run Python from a script, sys.path[0] is an actual
directory name, so that even if you chdir, any future imports will
still occur relative to the original directory.

Pretty confusing if you ask me.  Unfortunately Python is very
unPythonic when it comes to importing.  :(


Carl Banks


From http  Wed Jul 15 20:32:34 2009
From: http (Paul Rubin)
Date: 15 Jul 2009 17:32:34 -0700
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<ae7da03e-5852-4dbe-b11c-37f4afc32dbe@n11g2000yqb.googlegroups.com>
Message-ID: <7x3a8xwjq5.fsf@ruckus.brouhaha.com>

Anthony Tolle <anthony.tolle at gmail.com> writes:
> def xor(*operands):
>     if operands:
>         operands = list(operands)
>         a = bool(operands.pop(0))
>         while operands:
>             b = bool(operands.pop(0))
>             if a:
>                 if b:
>                     a = False
>             elif b:
>                 a = True
>         return a
>     return False

Among other things, that uses quadratic time!  Why do you want to keep
popping items from that list instead of iterating through it anyway?

Anyway, I think you wrote something close to this:

def xor(*operands):
   r = False
   for x in operands:
      r = (r != bool(x))
   return r

or in map-reduce style:

    from operator import ne
    def xor(*operands):
       return reduce(ne, map(bool, operands), False)


From wuwei23 at gmail.com  Wed Jul 15 20:41:41 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 17:41:41 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
Message-ID: <02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>

On Jul 16, 10:07?am, pdlem... at earthlink.net wrote:
> The WConio console module produces different colors, sometimes quite
> different, when run from Windows command line vs from Python
> interpreter >>> . ?A good foregnd/backgnd combination under one
> may be unreadable under the other ?: (
> I'm using Python 3.0 with the corresponding WConio on XP.
> Is there any way for the module to detect under which it has been
> started ? ? ?Thanks

It's recommended that you search through the list for similar
questions before posting. This was covered just yesterday:
http://groups.google.com/group/comp.lang.python/browse_frm/thread/fb2f075ccc796b63#


From wuwei23 at gmail.com  Wed Jul 15 20:47:39 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 17:47:39 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
Message-ID: <52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com>

On Jul 16, 10:41?am, alex23 <wuwe... at gmail.com> wrote:
> It's recommended that you search through the list for similar
> questions before posting.

Of course, it's even MORE important that one actually ensures they're
responding to the _same_ question before pointing at an answer...

This older post should help:
http://groups.google.com/group/comp.lang.python/browse_frm/thread/6c587ba377ae045a/0df10b077f5ee5d4

But the quick answer is to import sys into your program, and do a test
on hasattr(sys, 'ps1'), which is only created when running the
interactive prompt.


From pdlemper at earthlink.net  Wed Jul 15 21:36:57 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Wed, 15 Jul 2009 20:36:57 -0500
Subject: Can module tell if running from interpreter vs Windows command
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
Message-ID: <oq0t55pmvlsgt1p0ves5jm7mtl2a74rq0g@4ax.com>

On Wed, 15 Jul 2009 19:07:18 -0500, pdlemper at earthlink.net wrote:

>The WConio console module produces different colors, sometimes quite
>different, when run from Windows command line vs from Python
>interpreter >>> .  A good foregnd/backgnd combination under one
>may be unreadable under the other  : (
>I'm using Python 3.0 with the corresponding WConio on XP.
>Is there any way for the module to detect under which it has been 
>started ?    Thanks
Thanks Alex   It worked :

   import sys
   
   hasattr(sys, 'ps1')   yields True when started from interpreter >>>
                            and False run from Windows command line
Dave WB3DWE


From wuwei23 at gmail.com  Wed Jul 15 22:30:11 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 19:30:11 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com> 
	<56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com>
Message-ID: <30a6179e-f08a-4809-8c3d-50e083114d50@y10g2000prg.googlegroups.com>

On Jul 15, 5:51?pm, koranthala <koranth... at gmail.com> wrote:
> ? ?I am not saying that what you said was wrong, only that I felt that
> she got tense looking up regular expressions. So a python reply which
> basically does the basic checking without going to re etc might be
> more helpful for her to start her own coding.

Using regexps wasn't the only advice given, and string manipulation is
covered well in pretty much every tutorial I've taken a look at. The
issue is that no evidence was shown that the OP was even trying to
resolve this themself, and the new posting of the question every time
an unsatisfactory answer was provided doesn't give me any faith they
were endeavouring to do this at all.

It's annoying seeing these "stone soup" attempts at coding come
through here, whether its to answer someone's homework or to do
someone's job for them. If the end result has value to the poster, I
expect to see either effort on their behalf or at least a nominal
attempt to reward others for their time.

But if you want to do their work for them, I don't think anyone here
would object, especially if you both took it to private correspondence.


From afriere at yahoo.co.uk  Wed Jul 15 22:56:38 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Wed, 15 Jul 2009 19:56:38 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
	<52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com>
Message-ID: <0fc81395-7787-48a9-93de-cf7a274b691e@u38g2000pro.googlegroups.com>

On Jul 16, 10:47?am, alex23 <wuwe... at gmail.com> wrote:

...

> This older post should help:http://groups.google.com/group/comp.lang.python/browse_frm/thread/6c5...
>
> But the quick answer is to import sys into your program, and do a test
> on hasattr(sys, 'ps1'), which is only created when running the
> interactive prompt.

As you note there, this will work when running the vanilla shell (ie
running  it from the command line), but not (potentially) in other
interactive environments (IronPython being the example you give).
Another instance:  there is not sys.ps1 when running a python shell
under idle.  Since this solution differs whether the interactive
session is taking place from the cmd line, idle, IronPython etc. it
seems to me not terribly robust.

Depending on the use case, it is of course easy to tell whether the
module was executed on the command line, or imported (from an
interactive shell or another script) using the __name__ trick.  (eg.
is_imported = __name__ == '__main__')




From koranthala at gmail.com  Wed Jul 15 23:42:51 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 20:42:51 -0700 (PDT)
Subject: mail
References: <mailman.3184.1247683595.8015.python-list@python.org>
Message-ID: <55d3cd26-44a2-4b87-8bb4-988e8c397833@v15g2000prn.googlegroups.com>

On Jul 15, 11:46?pm, amr... at iisermohali.ac.in wrote:
> Dear all,
>
> Sorry that I am disturbing you all again and again but this is the way I
> am trying to solve my problem:---
>
> >>> import re
> >>> exp = re.compile("CA")
> >>> infile = open("file1.txt")
> >>> for line in infile:
>
> ... ? ? values = re.split("\s+", line)
> ... ? ? if exp.search(line):
> ... ? ? ? ?print ("%s %s CA = %s" %(values[2], values[3], values[6]))
> ...
> ?with this it is giving the output like:----
>
> 8 ALA CA = 54.67
> 15 ALA CA = 52.18
> 21 ALA CA = 54.33
> 23 ALA CA = 55.84
> 33 ALA CA = 55.58
> 38 ALA CA = 54.33
>
> which is all right but i want CB and C value also in each row and it
> should take value from 5th column infront of them, file is something
> lookin like:-----
>
> ?47 ? ? 8 ? ALA ? ? ? H ? ? H ? ? ?7.85 ? ? 0.02 ? ? 1
> ?48 ? ? 8 ? ALA ? ? ? HA ? ?H ? ? ?2.98 ? ? 0.02 ? ? 1
> ?49 ? ? 8 ? ALA ? ? ? HB ? ?H ? ? ?1.05 ? ? 0.02 ? ? 1
> ?50 ? ? 8 ? ALA ? ? ? C ? ? C ? ?179.39 ? ? ?0.3 ? ? 1
> ?51 ? ? 8 ? ALA ? ? ? CA ? ?C ? ? 54.67 ? ? ?0.3 ? ? 1
> ?52 ? ? 8 ? ALA ? ? ? CB ? ?C ? ? 18.85 ? ? ?0.3 ? ? 1
> ?53 ? ? 8 ? ALA ? ? ? N ? ? N ? ?123.95 ? ? ?0.3 ? ? 1
> 107 ? ?15 ? ALA ? ? ? H ? ? H ? ? ?8.05 ? ? 0.02 ? ? 1
> 108 ? ?15 ? ALA ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
> 109 ? ?15 ? ALA ? ? ? HB ? ?H ? ? ?1.29 ? ? 0.02 ? ? 1
> 110 ? ?15 ? ALA ? ? ? C ? ? C ? ?177.18 ? ? ?0.3 ? ? 1
> 111 ? ?15 ? ALA ? ? ? CA ? ?C ? ? 52.18 ? ? ?0.3 ? ? 1
> 112 ? ?15 ? ALA ? ? ? CB ? ?C ? ? 20.64 ? ? ?0.3 ? ? 1
> 113 ? ?15 ? ALA ? ? ? N ? ? N ? ?119.31 ? ? ?0.3 ? ? 1
> 154 ? ?21 ? ALA ? ? ? H ? ? H ? ? ?7.66 ? ? 0.02 ? ? 1
> 155 ? ?21 ? ALA ? ? ? HA ? ?H ? ? ?4.05 ? ? 0.02 ? ? 1
> 156 ? ?21 ? ALA ? ? ? HB ? ?H ? ? ?1.39 ? ? 0.02 ? ? 1
> 157 ? ?21 ? ALA ? ? ? C ? ? C ? ?179.35 ? ? ?0.3 ? ? 1
> 158 ? ?21 ? ALA ? ? ? CA ? ?C ? ? 54.33 ? ? ?0.3 ? ? 1
> 159 ? ?21 ? ALA ? ? ? CB ? ?C ? ? 17.87 ? ? ?0.3 ? ? 1
> 160 ? ?21 ? ALA ? ? ? N ? ? N ? ?123.58 ? ? ?0.3 ? ? 1
> 169 ? ?23 ? ALA ? ? ? H ? ? H ? ? ?8.78 ? ? 0.02 ? ? 1
> 170 ? ?23 ? ALA ? ? ? HA ? ?H ? ? ?4.14 ? ? 0.02 ? ? 1
> 171 ? ?23 ? ALA ? ? ? HB ? ?H ? ? ?1.62 ? ? 0.02 ? ? 1
> 172 ? ?23 ? ALA ? ? ? C ? ? C ? ?179.93 ? ? ?0.3 ? ? 1
> 173 ? ?23 ? ALA ? ? ? CA ? ?C ? ? 55.84 ? ? ?0.3 ? ? 1
> 174 ? ?23 ? ALA ? ? ? CB ? ?C ? ? 17.55 ? ? ?0.3 ? ? 1
> 175 ? ?23 ? ALA ? ? ? N ? ? N ? ?120.16 ? ? ?0.3 ? ? 1
> 232 ? ?33 ? ALA ? ? ? H ? ? H ? ? ?7.57 ? ? 0.02 ? ? 1
> 233 ? ?33 ? ALA ? ? ? HA ? ?H ? ? ?3.89 ? ? 0.02 ? ? 1
> 234 ? ?33 ? ALA ? ? ? HB ? ?H ? ? ?1.78 ? ? 0.02 ? ? 1
> 235 ? ?33 ? ALA ? ? ? C ? ? C ? ?179.24 ? ? ?0.3 ? ? 1
> 236 ? ?33 ? ALA ? ? ? CA ? ?C ? ? 55.58 ? ? ?0.3 ? ? 1
> 237 ? ?33 ? ALA ? ? ? CB ? ?C ? ? 19.75 ? ? ?0.3 ? ? 1
> 238 ? ?33 ? ALA ? ? ? N ? ? N ? ?121.52 ? ? ?0.3 ? ? 1
> 269 ? ?38 ? ALA ? ? ? H ? ? H ? ? ?8.29 ? ? 0.02 ? ? 1
> 270 ? ?38 ? ALA ? ? ? HA ? ?H ? ? ?4.04 ? ? 0.02 ? ? 1
> 271 ? ?38 ? ALA ? ? ? HB ? ?H ? ? ?1.35 ? ? 0.02 ? ? 1
> 272 ? ?38 ? ALA ? ? ? C ? ? C ? ?178.95 ? ? ?0.3 ? ? 1
> 273 ? ?38 ? ALA ? ? ? CA ? ?C ? ? 54.33 ? ? ?0.3 ? ? 1
> 274 ? ?38 ? ALA ? ? ? CB ? ?C ? ? 18.30 ? ? ?0.3 ? ? 1
> 275 ? ?38 ? ALA ? ? ? N ? ? N ? ?120.62 ? ? ?0.3 ? ? 1
>
> I just want that it will give output something like:-----
>
> 8 ?ALA ?C = 179.39 ?CA = 54.67 ?CB = 18.85
> 15 ALA ?C = 177.18 ?CA = 52.18 ?CB = 20.64
> 21 ALA ?C = 179.35 ?CA = 54.33 ?CB = 17.87.....
>
> so first it will write the position of the amino acid(given by second
> column)then amino acid here it is ALA and then the corresponding value of
> C, CA and CB from 5th colum for each position of ALA.
>
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA

Hi,
   Can you try using the code which I suggested in the earlier thread?
   If you cannot use it to get the output, just point it out here, and
I will try to solve the issue.


From nagle at animats.com  Thu Jul 16 00:03:58 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 15 Jul 2009 21:03:58 -0700
Subject: does python have a generic object pool like commons-pool in Java
In-Reply-To: <12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
Message-ID: <4a5ea61b$0$1682$742ec2ed@news.sonic.net>

Rick Lawson wrote:
> On Jul 15, 4:53 am, Jonathan Gardner <jgard... at jonathangardner.net>
> wrote:
>> On Jul 14, 6:34 pm, Rick Lawson <lawso... at gmail.com> wrote:
>>
>>> Appreciate any help on this. I am porting an app from Java to python
>>> and need generic object pooling with hooks for object initialization /
>>> cleanup and be able to specify an object timeout.
>> Are you looking for something like a thread pool or a connection pool?
>> Such a thing is easy to code in Python. Might as well write one from
>> scratch for your particular need.
>>
>> By the way, a tip for writing Python: Forget Java. If you're porting
>> an app, consider rewriting it from the architecture on up. You'll save
>> yourself time and get a better result.
> 
> Jonathan,
> 
> Thanks for the advice but would like to pick your brain a little more.
> The pool I need is not a thread pool or db pool. I need to pool
> objects which are a proxy for an external C process that communicates
> via sockets. 

     "fcgi" is an option for this sort of thing.  With "mod_fcgi" installed
in Apache, and "fcgi.py" used to manage the Python side of the problem, you
can have semi-persistent programs started up and shut down for you on the
server side.

    I use this for "sitetruth.com".  It's useful when CGI is too slow
because the cost of launching Python and loading all the modules is
far greater than the cost of processing the request.

    Once you find and install a working Apache "mod_fcgi" module, and a
working "fcgi.py" module (I suggest "http://svn.saddi.com/py-lib/trunk/fcgi.py") 
writing the server side app is no harder than with CGI.  But the performance
is far better.

				John Nagle


From wuwei23 at gmail.com  Thu Jul 16 00:14:37 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 21:14:37 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
	<52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com> 
	<0fc81395-7787-48a9-93de-cf7a274b691e@u38g2000pro.googlegroups.com>
Message-ID: <35b0b936-6bc1-4acf-aa27-6cc0db84292b@y10g2000prf.googlegroups.com>

On Jul 16, 12:56?pm, Asun Friere <afri... at yahoo.co.uk> wrote:
> As you note there, this will work when running the vanilla shell (ie
> running ?it from the command line), but not (potentially) in other
> interactive environments (IronPython being the example you give).

Actually, that was IPython, which is an enhanced interactive prompt,
and a totally different beastie altogether :)

> Another instance: ?there is not sys.ps1 when running a python shell
> under idle. ?Since this solution differs whether the interactive
> session is taking place from the cmd line, idle, IronPython etc. it
> seems to me not terribly robust.

Well, none of {idle, IronPython, IPython} were specified by the OP AND
you're citing back what I myself wrote in the link to which I also
referred the OP - whom has subsequently posted his success with this
technique - so I'm not really sure what the point is here other than
"if you have a different use case, you'll need a different
solution"...

> Depending on the use case, it is of course easy to tell whether the
> module was executed on the command line, or imported (from an
> interactive shell or another script) using the __name__ trick.  (eg.
> is_imported = __name__ == '__main__')

That should be:

is_imported = __name__ != '__main__'

And such a test is all well and good if the main code body is the one
that needs to know about the execution mode, but if you need to know
under which conditions the program is being run within a module
imported by the main body, well, that check is _always_ going to be
true...


From phostu at gmail.com  Thu Jul 16 00:18:39 2009
From: phostu at gmail.com (Vincent)
Date: Wed, 15 Jul 2009 21:18:39 -0700 (PDT)
Subject: problem about cx_Oracle
Message-ID: <957ab843-92ac-4072-ace4-441a2da0d130@m3g2000pri.googlegroups.com>

hi, all:

i am using cx_oracle now.

i write code as below:

def __getfields_by_tbname(self,tbname):
        cursor = self.ora_db.cursor()
        print tbname
        sql = 'select * from %s where rownum <=2' % tbname
        print sql
        cursor = cursor.execute(sql)
        return self.getfields(cursor)

and i got a error, it's message is :
JRYZCFZB_X_ZQY
select * from JRYZCFZB_X_ZQY where rownum <=2
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
\data_convert.py", line 107, in convert
    self.convert_table(tbname)
  File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
\data_convert.py", line 94, in convert_table
    field_list = self.__getfields_by_tbname(tbname)
  File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
\data_convert.py", line 38, in __getfields_by_tbname
    cursor = cursor.execute(sql)
TypeError: expecting None or a string

i'm sure the cursor instance is not None.
could anybody give me sussgestion? i will apreciate it.

vincent


From koranthala at gmail.com  Thu Jul 16 00:29:04 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 21:29:04 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com> 
	<56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com> 
	<30a6179e-f08a-4809-8c3d-50e083114d50@y10g2000prg.googlegroups.com>
Message-ID: <ee806cef-f159-4aae-b768-2c62eb3457b8@m3g2000pri.googlegroups.com>

On Jul 16, 7:30?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 15, 5:51?pm, koranthala <koranth... at gmail.com> wrote:
>
> > ? ?I am not saying that what you said was wrong, only that I felt that
> > she got tense looking up regular expressions. So a python reply which
> > basically does the basic checking without going to re etc might be
> > more helpful for her to start her own coding.
>
> Using regexps wasn't the only advice given, and string manipulation is
> covered well in pretty much every tutorial I've taken a look at. The
> issue is that no evidence was shown that the OP was even trying to
> resolve this themself, and the new posting of the question every time
> an unsatisfactory answer was provided doesn't give me any faith they
> were endeavouring to do this at all.
>
> It's annoying seeing these "stone soup" attempts at coding come
> through here, whether its to answer someone's homework or to do
> someone's job for them. If the end result has value to the poster, I
> expect to see either effort on their behalf or at least a nominal
> attempt to reward others for their time.
>
> But if you want to do their work for them, I don't think anyone here
> would object, especially if you both took it to private correspondence.

It is not that I do want to do the work for them. It is just that I
was in the same position just 6 months back. My first pieces of code
were very poor - full of errors and quite horrible indeed. I was even
afraid to post it anywhere. I came here, and I found so much helpful
people who helped me out so much, that I think my coding has improved
a little bit. So, I just thought that we should always give people the
benefit of doubt.



From wuwei23 at gmail.com  Thu Jul 16 00:30:40 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 21:30:40 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com> 
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com> 
	<4a5ea61b$0$1682$742ec2ed@news.sonic.net>
Message-ID: <0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>

On Jul 16, 2:03?pm, John Nagle <na... at animats.com> wrote:
> ? ? ?"fcgi" is an option for this sort of thing. ?With "mod_fcgi" installed
> in Apache, and "fcgi.py" used to manage the Python side of the problem, you
> can have semi-persistent programs started up and shut down for you on the
> server side.

Hey John,

The environments in which I've been asked to develop webs apps using
Python have all utilised mod_wsgi. Do you have any experience with
mod_wsgi vs mod_fcgi, and if so, can you comment on any relevant
performance / capability / ease-of-use differences?

Cheers,
alex23




From akhilanger at gmail.com  Thu Jul 16 00:34:06 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 21:34:06 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
	position 13: ordinal not in range(128)
Message-ID: <24509879.post@talk.nabble.com>


Hi!

Can anyone please help me getting rid of this error:
UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
13: ordinal not in range(128)

I am not a python programmer (though intend to start learning this wonderful
language), I am just using a python script.

After doing some search, I found that 0xb7 is a 'middle dot character' that
is not interpreted by the python.
Even after inserting text = text.replace('\u00b7', '') in the script, the
problem still persists.

Can anyone please tell me the easiest way to get rid of this?

--Thanks,
Akhil
-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24509879.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From clp2 at rebertia.com  Thu Jul 16 00:39:19 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 21:39:19 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
In-Reply-To: <24509879.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
Message-ID: <50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>

On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>
> Hi!
>
> Can anyone please help me getting rid of this error:
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
> 13: ordinal not in range(128)
>
> I am not a python programmer (though intend to start learning this wonderful
> language), I am just using a python script.
>
> After doing some search, I found that 0xb7 is a 'middle dot character' that
> is not interpreted by the python.
> Even after inserting text = text.replace('\u00b7', '') in the script, the
> problem still persists.
>
> Can anyone please tell me the easiest way to get rid of this?

We'll need the full error traceback. The error message at the end is
just not enough information.
As to fixing it, google for "UnicodeEncodeError". You should find
about a million mailinglist threads on it.

Cheers,
Chris
-- 
http://blog.rebertia.com


From wuwei23 at gmail.com  Thu Jul 16 00:41:31 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 21:41:31 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com> 
	<56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com> 
	<30a6179e-f08a-4809-8c3d-50e083114d50@y10g2000prg.googlegroups.com> 
	<ee806cef-f159-4aae-b768-2c62eb3457b8@m3g2000pri.googlegroups.com>
Message-ID: <0f28ec7c-f0cc-4cfb-a518-e65dba6e094c@12g2000pri.googlegroups.com>

On Jul 16, 2:29?pm, koranthala <koranth... at gmail.com> wrote:
> It is not that I do want to do the work for them. It is just that I
> was in the same position just 6 months back. My first pieces of code
> were very poor - full of errors and quite horrible indeed. I was even
> afraid to post it anywhere. I came here, and I found so much helpful
> people who helped me out so much, that I think my coding has improved
> a little bit. So, I just thought that we should always give people the
> benefit of doubt.

Which is why I waited until the 5th repeated post on the topic before
commenting.


From nagle at animats.com  Thu Jul 16 01:05:01 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 15 Jul 2009 22:05:01 -0700
Subject: does python have a generic object pool like commons-pool in Java
In-Reply-To: <0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
	<4a5ea61b$0$1682$742ec2ed@news.sonic.net>
	<0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>
Message-ID: <4a5eb46a$0$1673$742ec2ed@news.sonic.net>

alex23 wrote:
> On Jul 16, 2:03 pm, John Nagle <na... at animats.com> wrote:
>>      "fcgi" is an option for this sort of thing.  With "mod_fcgi" installed
>> in Apache, and "fcgi.py" used to manage the Python side of the problem, you
>> can have semi-persistent programs started up and shut down for you on the
>> server side.
> 
> Hey John,
> 
> The environments in which I've been asked to develop webs apps using
> Python have all utilised mod_wsgi. Do you have any experience with
> mod_wsgi vs mod_fcgi, and if so, can you comment on any relevant
> performance / capability / ease-of-use differences?
> 
> Cheers,
> alex23

    FCGI seems to be somewhat out of favor, perhaps because it isn't
complicated enough. It's a mature technology and works reasonably
well.  It's been a puzzle to me that FCGI was taken out of the
main Apache code base, because it gives production-level performance
with CGI-type simplicity.

    WSGI has a mode for running Python inside the Apache process,
which is less secure and doesn't allow multiple Python processes.
That complicates mod_wsgi considerably, and ties it very closely
to specific versions of Python and Python modules.  As a result,
the WSGI developers are patching at a great rate.  I think the
thing has too many "l33t features".

I'd avoid "embedded mode".  "Daemon mode" is the way to go if you use WSGI.
I haven't tried WSGI; I don't need the grief of a package under
heavy development.

					John Nagle


From akhilanger at gmail.com  Thu Jul 16 01:05:20 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 22:05:20 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
Message-ID: <24510222.post@talk.nabble.com>


Well, 
All I get is this traceback:

File "./customWikiExtractor.py", line 492, in ?
     main()
File "./customWikiExtractor.py", line 480, in main
    print >> sys.stdout, 'line: %s' % line
UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
13: ordinal not in range(128)

I am giving a string to the python code as input, and python processes it
like this:

line = line.decode('utf-8').strip()

After this when I do, 
print >> sys.stdout, 'line: %s' % line
I get this Unicode error.

I tried a few repairs, but they did not work like
changing: in sgmmlib.py (/usr/lib64/python2.4/sgmmlib.py) 
if not 0 < n <= 255
    to
if not 0 < n <= 127 

But since this did not work, I have changed it back to it's original form.

--Thanks,
Akhil


Chris Rebert-6 wrote:
> 
> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>
>> Hi!
>>
>> Can anyone please help me getting rid of this error:
>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>> position
>> 13: ordinal not in range(128)
>>
>> I am not a python programmer (though intend to start learning this
>> wonderful
>> language), I am just using a python script.
>>
>> After doing some search, I found that 0xb7 is a 'middle dot character'
>> that
>> is not interpreted by the python.
>> Even after inserting text = text.replace('\u00b7', '') in the script, the
>> problem still persists.
>>
>> Can anyone please tell me the easiest way to get rid of this?
> 
> We'll need the full error traceback. The error message at the end is
> just not enough information.
> As to fixing it, google for "UnicodeEncodeError". You should find
> about a million mailinglist threads on it.
> 
> Cheers,
> Chris
> -- 
> http://blog.rebertia.com
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24510222.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From akhilanger at gmail.com  Thu Jul 16 01:09:38 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 22:09:38 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <24510222.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
Message-ID: <24510252.post@talk.nabble.com>


Sorry, it is sgmllib.py and not sgmmlib.py

-- Akhil

akhil1988 wrote:
> 
> Well, 
> All I get is this traceback:
> 
> File "./customWikiExtractor.py", line 492, in ?
>      main()
> File "./customWikiExtractor.py", line 480, in main
>     print >> sys.stdout, 'line: %s' % line
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
> position 13: ordinal not in range(128)
> 
> I am giving a string to the python code as input, and python processes it
> like this:
> 
> line = line.decode('utf-8').strip()
> 
> After this when I do, 
> print >> sys.stdout, 'line: %s' % line
> I get this Unicode error.
> 
> I tried a few repairs, but they did not work like
> changing: in sgmmlib.py (/usr/lib64/python2.4/sgmmlib.py) 
> if not 0 < n <= 255
>     to
> if not 0 < n <= 127 
> 
> But since this did not work, I have changed it back to it's original form.
> 
> --Thanks,
> Akhil
> 
> 
> Chris Rebert-6 wrote:
>> 
>> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>>
>>> Hi!
>>>
>>> Can anyone please help me getting rid of this error:
>>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>>> position
>>> 13: ordinal not in range(128)
>>>
>>> I am not a python programmer (though intend to start learning this
>>> wonderful
>>> language), I am just using a python script.
>>>
>>> After doing some search, I found that 0xb7 is a 'middle dot character'
>>> that
>>> is not interpreted by the python.
>>> Even after inserting text = text.replace('\u00b7', '') in the script,
>>> the
>>> problem still persists.
>>>
>>> Can anyone please tell me the easiest way to get rid of this?
>> 
>> We'll need the full error traceback. The error message at the end is
>> just not enough information.
>> As to fixing it, google for "UnicodeEncodeError". You should find
>> about a million mailinglist threads on it.
>> 
>> Cheers,
>> Chris
>> -- 
>> http://blog.rebertia.com
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24510252.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From clp2 at rebertia.com  Thu Jul 16 01:12:08 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 22:12:08 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
In-Reply-To: <24510222.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
Message-ID: <50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>

> Chris Rebert-6 wrote:
>>
>> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>>
>>> Hi!
>>>
>>> Can anyone please help me getting rid of this error:
>>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>>> position
>>> 13: ordinal not in range(128)
>>>
>>> I am not a python programmer (though intend to start learning this
>>> wonderful
>>> language), I am just using a python script.
>>>
>>> After doing some search, I found that 0xb7 is a 'middle dot character'
>>> that
>>> is not interpreted by the python.
>>> Even after inserting text = text.replace('\u00b7', '') in the script, the
>>> problem still persists.
>>>
>>> Can anyone please tell me the easiest way to get rid of this?
>>
>> We'll need the full error traceback. The error message at the end is
>> just not enough information.
>> As to fixing it, google for "UnicodeEncodeError". You should find
>> about a million mailinglist threads on it.
On Wed, Jul 15, 2009 at 10:05 PM, akhil1988<akhilanger at gmail.com> wrote:
>
> Well,
> All I get is this traceback:
>
> File "./customWikiExtractor.py", line 492, in ?
>     main()
> File "./customWikiExtractor.py", line 480, in main
>    print >> sys.stdout, 'line: %s' % line
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
> 13: ordinal not in range(128)
>
> I am giving a string to the python code as input, and python processes it
> like this:
>
> line = line.decode('utf-8').strip()
>
> After this when I do,
> print >> sys.stdout, 'line: %s' % line
> I get this Unicode error.

Try this instead (the ">> sys.stdout" part is redundant):
print (u'line: %s' % line).encode('utf8')
#if your system doesn't use UTF-8, change as necessary

Cheers,
Chris
-- 
http://blog.rebertia.com


From peter.fodrek at stuba.sk  Thu Jul 16 01:16:57 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 07:16:57 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <7c6bdkF26j00sU1@mid.uni-berlin.de>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<7c6bdkF26j00sU1@mid.uni-berlin.de>
Message-ID: <200907160716.57648.peter.fodrek@stuba.sk>


On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:
> Peter Fodrek wrote:
......
> What does
>
> import nc
> print nc.__file__

python
Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
[GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import nc
>>> print nc.__file__
nc/__init__.pyc

and as well

ls nc             
attach.py       hpgl2dv_read.py  iso_codes.pyc  nc_read.py     
emc2.py         hpgl3d.py        iso.py         nc_read.pyc    rez.pyc
emc2_read.py    hpgl3d_read.py   iso_read.py    num_reader.py  rez_read.py
hpgl2d.py       __init__.py      machines.txt   rez_codes.py   siegkx1.py 
hpgl2d_read.py  __init__.pyc     nc.py               siegkx1_read.py
hpgl2dv.py      iso_codes.py     nc.pyc         rez.py     


and module is compiled well
ls -la nc/rez*
-rwxr-xr-x 1 peto users  1391 2009-07-15 13:18 nc/rez_codes.py
-rwxrwxrwx 1 peto users   255 2009-07-15 14:28 nc/rez.py
-rwxr-xr-x 1 peto users   222 2009-07-15 14:28 nc/rez.pyc
-rwxr-xr-x 1 peto users  5920 2009-07-15 13:17 nc/rez_read.py

Thank you 

Peter


From peter.fodrek at stuba.sk  Thu Jul 16 01:20:53 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 07:20:53 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <c134cd82-495a-4084-8929-f08ba435a2a7@i6g2000yqj.googlegroups.com>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<c134cd82-495a-4084-8929-f08ba435a2a7@i6g2000yqj.googlegroups.com>
Message-ID: <200907160720.53656.peter.fodrek@stuba.sk>

On Thursday 16 July 2009 02:18:52 Carl Banks wrote:
> On Jul 15, 6:12 am, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> That's a tricky one, indeed.
>
> Here's my guess: test.py is a symlink to a file in another directory.

It is not true guess
ls -la test.py
-rw-r--r-- 1 peto users 1990 2009-07-15 14:19 test.py  

But maybe access rights  needed to be corrected...

Thank you 

Peter


From mensanator at aol.com  Thu Jul 16 01:28:31 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 15 Jul 2009 22:28:31 -0700 (PDT)
Subject: Why does Python not stop when it's supposed to?
Message-ID: <539781e9-1096-499e-851a-8d3e8247e52d@f10g2000vbf.googlegroups.com>

So, I'm playing around with Python (running 2.6 and
3.1 versions of IDLE). After I shut everything down
and close the windows, I notice the Task Manager's
activity light is still glowing.

In looking at the Process window I see this:

Image...    User Name  CPU Memory(... Description
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      216 K pythonw.exe
pythonw.exe mensanator  00      220 K pythonw.exe
pythonw.exe mensanator  00      220 K pythonw.exe
pythonw.exe mensanator  00      408 K pythonw.exe
pythonw.exe mensanator  00      180 K pythonw.exe
pythonw.exe mensanator  50   66,156 K pythonw.exe
pythonw.exe mensanator  00      600 K pythonw.exe
pythonw.exe mensanator  00      228 K pythonw.exe
pythonw.exe mensanator  00      208 K pythonw.exe
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      192 K pythonw.exe
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      180 K pythonw.exe
pythonw.exe mensanator  00    8,672 K pythonw.exe

I can't seem to reproduce this. Opening IDLE
causes two copies to appear. When RUN, a third
appears for a few moments and drops back to two.

Doing a RESTART SHELL also launches another copy
which also goes away momentarily.

So, with a 2.6 and a 3.1 IDLE running simultaneously,
there could be 6 copies at once.

And they eventually all go away when the windows
are closed.

How is it I end up with 16 copies, one of them still
running after all the windows are closed? I had to
manually do an [end process] on all of them.

If I was doing something wrong, i sure would like
to know what it is.


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 16 01:37:02 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 16 Jul 2009 05:37:02 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.05.37.03@REMOVE.THIS.cybersource.com.au>

On Wed, 15 Jul 2009 21:05:16 +0200, Jean-Michel Pichavant wrote:

> Didn't know that.
> So if I resume:
> - not 'foo' => False
> - 'foo' or 'foo' => 'foo'
> 
> I may be missing something, but honestly, Guido must have smoked some
> heavy stuff to write such logic, has he ?

No, it's perfectly reasonable, and not at all the product of mind-
altering drugs. Other languages do the same thing.


for x in alist or blist or clist:
    print x

will select the first non-empty list and iterate over that.



Every object in Python has a truth value. By convention, we say that 
objects are Something or Nothing.

0 None [] '' are examples of Nothing, or false values.

1 2.5 [x, y, z] 'foo' are examples of Something, or true values.

Note the distinction between lower-case "false" and "true" (adjectives), 
and title-case False and True (nouns).


`if x: ... else:` branches according to whether x is Something or 
Nothing, not whether it is True or False.

The operators `and` and `or` also return Something or Nothing, short-
circuiting as appropriate.



-- 
Steven


From phostu at gmail.com  Thu Jul 16 01:38:10 2009
From: phostu at gmail.com (Vincent)
Date: Wed, 15 Jul 2009 22:38:10 -0700 (PDT)
Subject: problem about cx_Oracle
References: <957ab843-92ac-4072-ace4-441a2da0d130@m3g2000pri.googlegroups.com>
Message-ID: <717d5451-ef6d-45df-9e77-2135c75f7a12@u38g2000pro.googlegroups.com>

On Jul 16, 12:18?pm, Vincent <pho... at gmail.com> wrote:
> hi, all:
>
> i am using cx_oracle now.
>
> i write code as below:
>
> def __getfields_by_tbname(self,tbname):
> ? ? ? ? cursor = self.ora_db.cursor()
> ? ? ? ? print tbname
> ? ? ? ? sql = 'select * from %s where rownum <=2' % tbname
> ? ? ? ? print sql
> ? ? ? ? cursor = cursor.execute(sql)
> ? ? ? ? return self.getfields(cursor)
>
> and i got a error, it's message is :
> JRYZCFZB_X_ZQY
> select * from JRYZCFZB_X_ZQY where rownum <=2
> Traceback (most recent call last):
> ? File "<input>", line 1, in <module>
> ? File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
> \data_convert.py", line 107, in convert
> ? ? self.convert_table(tbname)
> ? File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
> \data_convert.py", line 94, in convert_table
> ? ? field_list = self.__getfields_by_tbname(tbname)
> ? File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
> \data_convert.py", line 38, in __getfields_by_tbname
> ? ? cursor = cursor.execute(sql)
> TypeError: expecting None or a string
>
> i'm sure the cursor instance is not None.
> could anybody give me sussgestion? i will apreciate it.
>
> vincent

i have the answer now.

the variant sql is unicode.

i neet to convert it to string.



From pavlovevidence at gmail.com  Thu Jul 16 01:38:23 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 15 Jul 2009 22:38:23 -0700 (PDT)
Subject: import module unbelieveable behaviour
References: <mailman.3157.1247667587.8015.python-list@python.org> 
	<7c6bdkF26j00sU1@mid.uni-berlin.de>
	<mailman.3196.1247721417.8015.python-list@python.org>
Message-ID: <2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>

On Jul 15, 10:16?pm, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:
>
> > Peter Fodrek wrote:
> ......
> > What does
>
> > import nc
> > print nc.__file__
>
> python
> Python 2.6 (r26:66714, Feb ?3 2009, 20:49:49)
> [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> Type "help", "copyright", "credits" or "license" for more information.>>> import nc
> >>> print nc.__file__
>
> nc/__init__.pyc


What does it do if you run this from a script?

Also, what is sys.path[0] in both interactive and script?

Inside test.py, right before the line that imports nc.rez, add the
code "import sys; print sys.modules.get('nc')"; what does that output?

Is there an old nc.py or nc.pyc file anywhere?


Carl Banks

Carl Banks


From afriere at yahoo.co.uk  Thu Jul 16 01:44:40 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Wed, 15 Jul 2009 22:44:40 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
	<52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com> 
	<0fc81395-7787-48a9-93de-cf7a274b691e@u38g2000pro.googlegroups.com> 
	<35b0b936-6bc1-4acf-aa27-6cc0db84292b@y10g2000prf.googlegroups.com>
Message-ID: <6c572443-cf8e-403c-aa66-086007dca540@d15g2000prc.googlegroups.com>

On Jul 16, 2:14?pm, alex23 <wuwe... at gmail.com> wrote:

...

> AND
> you're citing back what I myself wrote in the link to which I also
> referred the OP - whom (sic) has subsequently posted his success with this
> technique - so I'm not really sure what the point is here other than
> "if you have a different use case, you'll need a different
> solution"...
>

Please don't take offence where none was intended.  I know that I was
citing you and that I was highlighting the caveat you raised,
explicitly so.  No criticism of your post was intended nor implied.
Moreover the fact that it worked for OP on a single occasion does not
speak for its robustness.

> > Depending on the use case, it is of course easy to tell whether the
> > module was executed on the command line, or imported (from an
> > interactive shell or another script) using the __name__ trick. ?(eg.
> > is_imported = __name__ == '__main__')
>
> That should be:
>
> is_imported = __name__ != '__main__'
>

Doh! ... Yup I actually used that when I tried it out, my bad.

> And such a test is all well and good if the main code body is the one
> that needs to know about the execution mode, but if you need to know
> under which conditions the program is being run within a module
> imported by the main body, well, that check is _always_ going to be
> true...

Which is what the paragraph you just quoted says.  Hence the attribute
is called 'is_imported' rather that 'running_non_interactively'.


From akhilanger at gmail.com  Thu Jul 16 01:52:24 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 22:52:24 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>
Message-ID: <24510519.post@talk.nabble.com>


Chris,

Using 

print (u'line: %s' % line).encode('utf-8')

the 'line' gets printed, but actually this print statement I was using just
for testing, actually my code operates on 'line', on which I use line =
line.decode('utf-8') as 'line' is read as bytes from a stream.

And if I use line = line.encode('utf-8'), 

I start getting other error like
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 4561:
ordinal not in range(128)
at line = line.replace('<<', u'?').replace('>>', u'?')


--Akhil

Chris Rebert-6 wrote:
> 
>> Chris Rebert-6 wrote:
>>>
>>> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>>>
>>>> Hi!
>>>>
>>>> Can anyone please help me getting rid of this error:
>>>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>>>> position
>>>> 13: ordinal not in range(128)
>>>>
>>>> I am not a python programmer (though intend to start learning this
>>>> wonderful
>>>> language), I am just using a python script.
>>>>
>>>> After doing some search, I found that 0xb7 is a 'middle dot character'
>>>> that
>>>> is not interpreted by the python.
>>>> Even after inserting text = text.replace('\u00b7', '') in the script,
>>>> the
>>>> problem still persists.
>>>>
>>>> Can anyone please tell me the easiest way to get rid of this?
>>>
>>> We'll need the full error traceback. The error message at the end is
>>> just not enough information.
>>> As to fixing it, google for "UnicodeEncodeError". You should find
>>> about a million mailinglist threads on it.
> On Wed, Jul 15, 2009 at 10:05 PM, akhil1988<akhilanger at gmail.com> wrote:
>>
>> Well,
>> All I get is this traceback:
>>
>> File "./customWikiExtractor.py", line 492, in ?
>>     main()
>> File "./customWikiExtractor.py", line 480, in main
>>    print >> sys.stdout, 'line: %s' % line
>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>> position
>> 13: ordinal not in range(128)
>>
>> I am giving a string to the python code as input, and python processes it
>> like this:
>>
>> line = line.decode('utf-8').strip()
>>
>> After this when I do,
>> print >> sys.stdout, 'line: %s' % line
>> I get this Unicode error.
> 
> Try this instead (the ">> sys.stdout" part is redundant):
> print (u'line: %s' % line).encode('utf8')
> #if your system doesn't use UTF-8, change as necessary
> 
> Cheers,
> Chris
> -- 
> http://blog.rebertia.com
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24510519.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From milesck at umich.edu  Thu Jul 16 01:59:54 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Thu, 16 Jul 2009 01:59:54 -0400
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <m2hbxdelqu.fsf@valheru.db3l.homeip.net>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<m2prc3dlfo.fsf@valheru.db3l.homeip.net>
	<mailman.3183.1247682273.8015.python-list@python.org>
	<m2hbxdelqu.fsf@valheru.db3l.homeip.net>
Message-ID: <1EAE7F84-0FA1-4688-8F2B-B5E6869E69B8@umich.edu>

On Jul 15, 2009, at 4:26 PM, David Bolen wrote:

> Miles Kaufmann <milesck at umich.edu> writes:
>
>> On Jul 14, 2009, at 5:06 PM, David Bolen wrote:
>>> Are you sure?  It seems to restrict them in the same block, but  
>>> not in
>>> the entire file.  At least I was able to use both space and tab
>>> indented blocks in the same file with Python 3.0 and 3.1.
>>
>> It seems to me that, within an indented block, Python 3.1 requires
>> that you are consistent in your use of indentation characters *for
>> that indentation level*.  For example, the following code seems to be
>> allowed:
>
> Um, right - in other words, what I said :-)

I wasn't trying to correct you, just being more explicit. :)  After  
reading your post, I still wasn't sure if the restriction on mixing  
spaces and tabs applied to nested blocks--I was surprised that the  
code sample I included was allowed.

-Miles



From list at qtrac.plus.com  Thu Jul 16 02:21:48 2009
From: list at qtrac.plus.com (Mark Summerfield)
Date: Wed, 15 Jul 2009 23:21:48 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
Message-ID: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>

Hi,

I'm just wondering why <, <=, >=, and > are not supported by
collections.OrderedDict:

    >>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
    >>> d2 = d1.copy()
    >>> d2["z"] = 4
    >>> d1 == d2
    False
    >>> d1 < d2
    Traceback (most recent call last):
    File "<pyshell#6>", line 1, in <module>
	d1 < d2
    TypeError: unorderable types: OrderedDict() < OrderedDict()

It just seems to me that since the items in ordered dictionaries are
ordered, it would make sense to do an item by item comparison from
first to last item in exactly the same way that Python compares lists
or tuples?


From peter.fodrek at stuba.sk  Thu Jul 16 02:38:57 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 08:38:57 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<mailman.3196.1247721417.8015.python-list@python.org>
	<2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>
Message-ID: <200907160838.57658.peter.fodrek@stuba.sk>

On Thursday 16 July 2009 07:38:23 Carl Banks wrote:
> On Jul 15, 10:16 pm, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> > On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:
> > > Peter Fodrek wrote:
> >
> > ......
> >
> > > What does
> > >
> > > import nc
> > > print nc.__file__
> >
> > python
> > Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
> > [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> > Type "help", "copyright", "credits" or "license" for more information.>>>
> > import nc
> >
> > >>> print nc.__file__
> >
> > nc/__init__.pyc
>
> What does it do if you run this from a script?

Ouch, I am and python rookie, that was needed to try to edit undocumented 
script from German author

this answers everything

/home/opt/HeeksCAD8/HeeksCNC> python ./test.py
/usr/local/lib/heekscnc/nc/__init__.py 

and it is because begining of the script

# -*- coding: utf-8 -*-
import sys
sys.path.insert(0,'/usr/local/lib/heekscnc/')
import kurve
import kurve_funcs
from nc.nc import *
import nc
print nc.__file__
import nc.rez

and

ls -a /usr/local/lib/heekscnc/nc
.          emc2_read.py    hpgl2dv_read.py  iso_codes.py  nc_read.py
..         hpgl2d.py       hpgl3d.py        iso.py        num_reader.py
attach.py  hpgl2d_read.py  hpgl3d_read.py   iso_read.py   siegkx1.py
emc2.py    hpgl2dv.py      __init__.py      nc.py         siegkx1_read.py

Thank you for your help, once more.


Peter


From peter.fodrek at stuba.sk  Thu Jul 16 02:48:55 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 08:48:55 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <200907160838.57658.peter.fodrek@stuba.sk>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>
	<200907160838.57658.peter.fodrek@stuba.sk>
Message-ID: <200907160848.55069.peter.fodrek@stuba.sk>

On Thursday 16 July 2009 08:38:57 Peter Fodrek wrote:
> On Thursday 16 July 2009 07:38:23 Carl Banks wrote:
> > On Jul 15, 10:16 pm, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> > > On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:

> sys.path.insert(0,'/usr/local/lib/heekscnc/')

I was mentioned that this adds system path to multipath list(As $PATH)  and it 
replaces path instead. That was problem..

Peter


From jackdied at gmail.com  Thu Jul 16 03:12:20 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Thu, 16 Jul 2009 03:12:20 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
Message-ID: <b8e622740907160012p10911831ub1488195d694e663@mail.gmail.com>

On Thu, Jul 16, 2009 at 2:21 AM, Mark Summerfield<list at qtrac.plus.com> wrote:
> Hi,
>
> I'm just wondering why <, <=, >=, and > are not supported by
> collections.OrderedDict:
>
> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
> ? ?>>> d2 = d1.copy()
> ? ?>>> d2["z"] = 4
> ? ?>>> d1 == d2
> ? ?False
> ? ?>>> d1 < d2
> ? ?Traceback (most recent call last):
> ? ?File "<pyshell#6>", line 1, in <module>
> ? ? ? ?d1 < d2
> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> It just seems to me that since the items in ordered dictionaries are
> ordered, it would make sense to do an item by item comparison from
> first to last item in exactly the same way that Python compares lists
> or tuples?

>>> import this
In the face of ambiguity, refuse the temptation to guess.

It isn't an OrderedDict thing, it is a comparison thing.  Two regular
dicts also raise an error if you try to LT them.  What does it mean
for a dict to be greater than or less than its peer?  Nothing, so we
refuse to guess.

-Jack


From list at qtrac.plus.com  Thu Jul 16 03:22:20 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 00:22:20 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
Message-ID: <9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>

On 16 July, 08:12, Jack Diederich <jackd... at gmail.com> wrote:
> On Thu, Jul 16, 2009 at 2:21 AM, Mark Summerfield<l... at qtrac.plus.com> wrote:
> > Hi,
>
> > I'm just wondering why <, <=, >=, and > are not supported by
> > collections.OrderedDict:
>
> > ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
> > ? ?>>> d2 = d1.copy()
> > ? ?>>> d2["z"] = 4
> > ? ?>>> d1 == d2
> > ? ?False
> > ? ?>>> d1 < d2
> > ? ?Traceback (most recent call last):
> > ? ?File "<pyshell#6>", line 1, in <module>
> > ? ? ? ?d1 < d2
> > ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> > It just seems to me that since the items in ordered dictionaries are
> > ordered, it would make sense to do an item by item comparison from
> > first to last item in exactly the same way that Python compares lists
> > or tuples?
> >>> import this
>
> In the face of ambiguity, refuse the temptation to guess.
>
> It isn't an OrderedDict thing, it is a comparison thing. ?Two regular
> dicts also raise an error if you try to LT them. ?What does it mean
> for a dict to be greater than or less than its peer? ?Nothing, so we
> refuse to guess.
>
> -Jack

You are right that it doesn't make sense to compare two dicts.

But OrderedDicts can be viewed logically as lists of (key,value)
tuples so they are much more like lists or tuples when it comes to
comparisons.

For example:

>>> l = [("a", 1), ("z", 2), ("k", 3)]
>>> l1 = l[:]
>>> l1[1] = ("z", 5)
>>> l < l1
True

But if you do:

>>> d = collections.OrderedDict(l)
>>> d1 = collections.OrderedDict(l1)

You can't use <, <=, =>, or >, even though ordered dictionaries
preserve the order and their items are just as comparable as those in
a list or tuple of tuples.


From nagle at animats.com  Thu Jul 16 03:26:18 2009
From: nagle at animats.com (John Nagle)
Date: Thu, 16 Jul 2009 00:26:18 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
In-Reply-To: <mailman.3194.1247720980.8015.python-list@python.org>
References: <24509879.post@talk.nabble.com>	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>	<24510222.post@talk.nabble.com>
	<mailman.3194.1247720980.8015.python-list@python.org>
Message-ID: <4a5ed587$0$1627$742ec2ed@news.sonic.net>

akhil1988 wrote:
> Sorry, it is sgmllib.py and not sgmmlib.py

    Oh, that bug again.  See

	http://bugs.python.org/issue1651995

It's a bug in SGMLParser.  When Python 2.5 restricted ASCII to 0..127,
SGMLParser needed to be modified, but wasn't.

I reported that bug in February 2007.  It was fixed in
Python 2.6 and 3.0 on March 31, 2009.

					John Nagle


From clp2 at rebertia.com  Thu Jul 16 03:30:26 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 00:30:26 -0700
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
Message-ID: <50697b2c0907160030x5abbf7a4i99d397236297c850@mail.gmail.com>

On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<list at qtrac.plus.com> wrote:
> Hi,
>
> I'm just wondering why <, <=, >=, and > are not supported by
> collections.OrderedDict:
>
> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
> ? ?>>> d2 = d1.copy()
> ? ?>>> d2["z"] = 4
> ? ?>>> d1 == d2
> ? ?False
> ? ?>>> d1 < d2
> ? ?Traceback (most recent call last):
> ? ?File "<pyshell#6>", line 1, in <module>
> ? ? ? ?d1 < d2
> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> It just seems to me that since the items in ordered dictionaries are
> ordered, it would make sense to do an item by item comparison from
> first to last item in exactly the same way that Python compares lists
> or tuples?

Use case? I'm curious.

Cheers,
Chris
-- 
http://blog.rebertia.com


From mail at microcorp.co.za  Thu Jul 16 03:43:53 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Thu, 16 Jul 2009 09:43:53 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org><057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com><50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com><h3j358$lhr$1@ger.gmane.org><mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <001201ca05e9$2b0a61e0$0d00a8c0@Hendrik>

"Hrvoje Niksic" <hniksic at x..s.org> wrote:


> Note that in Python A or B is in fact not equivalent to not(not A and
> not B).

De Morgan would turn in his grave.

- Hendrik




From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 16 03:51:29 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 16 Jul 2009 07:51:29 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au>

On Thu, 16 Jul 2009 00:30:26 -0700, Chris Rebert wrote:

> On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<list at qtrac.plus.com>
> wrote:
>> Hi,
>>
>> I'm just wondering why <, <=, >=, and > are not supported by
>> collections.OrderedDict:
>>
>> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3))) d2 =
>> ? ?>>> d1.copy()
>> ? ?>>> d2["z"] = 4
>> ? ?>>> d1 == d2
>> ? ?False
>> ? ?>>> d1 < d2
>> ? ?Traceback (most recent call last):
>> ? ?File "<pyshell#6>", line 1, in <module>
>> ? ? ? ?d1 < d2
>> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>>
>> It just seems to me that since the items in ordered dictionaries are
>> ordered, it would make sense to do an item by item comparison from
>> first to last item in exactly the same way that Python compares lists
>> or tuples?
> 
> Use case? I'm curious.


Surely it would be the same use case as for comparing two lists? There 
doesn't need to be a special "OrderedDict use case" beyond "an 
OrderedDict is just like a list of (key,value) tuples, but searches are 
faster".

Or maybe not. If OrderedDicts are sequences as well as mappings, then we 
should be able to sort them. And that seems a bit much even for me.



-- 
Steven


From eckhardt at satorlaser.com  Thu Jul 16 03:56:13 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Thu, 16 Jul 2009 09:56:13 +0200
Subject: allowing output of code that is unittested?
References: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>
Message-ID: <t133j6-g3a.ln1@satorlaser.homedns.org>

per wrote:
> i am using the standard unittest module to unit test my code. my code
> contains several print statements which i noticed are repressed when i
> call my unit tests using:
> 
> if __name__ == '__main__':
>     suite = unittest.TestLoader().loadTestsFromTestCase(TestMyCode)
>     unittest.TextTestRunner(verbosity=2).run(suite)

I have here

   if __name__ == '__main__':
       unittest.main()

preceded by classes which derive from unittest.TestCase. Running this allows
me to write to stdout using print as usual, even though it's ugly because
it clutters the output of the testcases.

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 16 04:19:21 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 16 Jul 2009 08:19:21 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<mailman.3205.1247730432.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.08.19.21@REMOVE.THIS.cybersource.com.au>

On Thu, 16 Jul 2009 09:43:53 +0200, Hendrik van Rooyen wrote:

> "Hrvoje Niksic" <hniksic at x..s.org> wrote:
> 
> 
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
> 
> De Morgan would turn in his grave.

No he wouldn't. Python isn't Boolean algebra, and there is no requirement 
to limit Python's operators to the semantics of Boolean algebra.



-- 
Steven


From info at egenix.com  Thu Jul 16 04:28:10 2009
From: info at egenix.com (eGenix Team: M.-A. Lemburg)
Date: Thu, 16 Jul 2009 10:28:10 +0200
Subject: EuroPython 2009: Making 50 Mio. EUR per year using Python
Message-ID: <4A5EE49A.8000207@egenix.com>

Now available as video...

http://www.egenix.com/company/news/EuroPython-2009-Lightning-Talk.html

Enjoy,
-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 16 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/




From vmalloc at gmail.com  Thu Jul 16 04:43:32 2009
From: vmalloc at gmail.com (Rotem)
Date: Thu, 16 Jul 2009 01:43:32 -0700 (PDT)
Subject: Memory leak involving traceback objects
Message-ID: <e6e9b9ea-1f8c-4695-90da-72e85c8a63e4@v20g2000yqm.googlegroups.com>

Hi,

I'm debugging a nasty memory leak in a framework written in Python
(v2.6.2).
After much digging around I found that the entire object group that is
leaking is held by a frame object which is subsequently held by a
traceback object.

Traversing the get_referrers() of each traceback frame leads
eventually to a root traceback frame which has no referrers
(gc.get_referrers returns an empty list).

However, this traceback object seems not to be picked by the garbage
collector, and is still there even after many iterations and calls to
gc.collect(). The code location to which the traceback frame points
doesn't do anything special - it just catches an exception, without
saving the exception itself and/or traceback anywhere.

Before I dive into the Python code itself - does anyone have any idea
what can cause this?

Thanks,

Rotem


From piet at cs.uu.nl  Thu Jul 16 04:48:57 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 10:48:57 +0200
Subject: How to Force exiting from program/script
References: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>
Message-ID: <m28wipvwqu.fsf@cs.uu.nl>

>>>>> Alex <magobin at gmail.com> (A) a ?crit:

>A> hi at all,
>A>  I have made a script with a while loop and I want that after 30
>A> seconds the program stop and exit . But the code like this doesn't
>A> run:
>A> In the Console I can see work so that function is correctly called...

>A> #Function to exit
>A> def exit():
>A>     print "work"
>A>     raise SystemExit()
>A> t = threading.Timer(30.0, exit)
>A> t.start()

>A> # Loop
>A> while True:
>A> ...many lines....

This code gives you a bit more control as it doesn't just force a system
exit, but allows you to continue some other work after aborting the
loop:

import signal, os
from threading import Timer

signalcode = signal.SIGALRM
class AlarmError(Exception):
    pass

def handler(signum, frame):
    raise AlarmError, "command lasts too long"

signal.signal(signalcode, handler)

def interrupt():
    os.kill(os.getpid(), signalcode)

def execute(function, timeout):
    Timer(timeout, interrupt).start()
    try:
        function()
    except AlarmError, e:
        print e
        print 'Execution aborted'

def long_function():
    while True:
        pass
    
print "The everlasting command"
execute(long_function, 10)
print "The End"

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From l.mastrodomenico at gmail.com  Thu Jul 16 05:02:55 2009
From: l.mastrodomenico at gmail.com (Lino Mastrodomenico)
Date: Thu, 16 Jul 2009 11:02:55 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <001201ca05e9$2b0a61e0$0d00a8c0@Hendrik>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<001201ca05e9$2b0a61e0$0d00a8c0@Hendrik>
Message-ID: <cc93256f0907160202u3dc09e8av2b31ad755ca01b39@mail.gmail.com>

2009/7/16 Hendrik van Rooyen <mail at microcorp.co.za>:
> "Hrvoje Niksic" <hniksic at x..s.org> wrote:
>
>
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>
> De Morgan would turn in his grave.

If this can make him happier, in Python (not (not a and not b)) *is*
equivalent to bool(a or b). (Modulo crazy things like redefining
"bool" or having a __bool__ with side effects.)

In the first expression you implicitly request a bool because you use
"not", in the second one you do this with an explicit "bool".

-- 
Lino Mastrodomenico


From jeanmichel at sequans.com  Thu Jul 16 05:06:54 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 16 Jul 2009 11:06:54 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.15.23.01.37.844000@nowhere.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
Message-ID: <4A5EEDAE.3040605@sequans.com>

Nobody wrote:
> On Wed, 15 Jul 2009 21:05:16 +0200, Jean-Michel Pichavant wrote:
>
>   
>> So if I resume:
>> - not 'foo' => False
>> - 'foo' or 'foo' => 'foo'
>>
>> I may be missing something, but honestly, Guido must have smoked some 
>> heavy stuff to write such logic, has he ?
>>     
>
> Several languages (e.g. Lisp, Bourne shell) behave the same way, i.e. "or"
> returns the first element which is considered true while "and" returns the
> last element provided that all preceding elements are considered true.
>   
> [snip]
>   

Ok then, why "or" does not return True, if the first element is 
considered True ? Why returning the element itself. Any reason for that 
? Because it's confusing, maybe people used to that logic find it 
obvious, but I really don't.

JM


From piet at cs.uu.nl  Thu Jul 16 05:09:51 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 11:09:51 +0200
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>
	<mailman.3198.1247723546.8015.python-list@python.org>
Message-ID: <m24otdvvs0.fsf@cs.uu.nl>

>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:

>a> Chris,

>a> Using 

>a> print (u'line: %s' % line).encode('utf-8')

>a> the 'line' gets printed, but actually this print statement I was using just
>a> for testing, actually my code operates on 'line', on which I use line =
>a> line.decode('utf-8') as 'line' is read as bytes from a stream.

>a> And if I use line = line.encode('utf-8'), 

>a> I start getting other error like
>a> UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 4561:
>a> ordinal not in range(128)
>a> at line = line.replace('<<', u'?').replace('>>', u'?')

You do a Unicode replace here, so line should be a unicode string.
Therefore you have to do this before the line.encode('utf-8'), but after
the decode('utf-8'). 

It might be better to use different variables for Unicode strings and
byte code strings to prevent confusion, like:

'line' is read as bytes from a stream
uline = line.decode('utf-8')
uline = uline.replace('<<', u'?').replace('>>', u'?')
line = uline.encode('utf-8')
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jarausch at igpm.rwth-aachen.de  Thu Jul 16 05:12:25 2009
From: jarausch at igpm.rwth-aachen.de (Helmut Jarausch)
Date: Thu, 16 Jul 2009 11:12:25 +0200
Subject: How to search this newsgroup by a python script.
Message-ID: <7c897lF26dea4U1@mid.dfncis.de>

Hi,

I haven't found anything with Google's group search, so let me
ask it (again?).

How can I search this newsgroup from within a Python script.
(Perhaps by searching Google Groups or Gmane by some Python code.)

Many thanks for a hint,
Helmut.

-- 
Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany


From piet at cs.uu.nl  Thu Jul 16 05:21:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 11:21:54 +0200
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>
Message-ID: <m2zlb5ugnh.fsf@cs.uu.nl>

>>>>> Mark <list at qtrac.plus.com> (M) wrote:

>M> You are right that it doesn't make sense to compare two dicts.

>M> But OrderedDicts can be viewed logically as lists of (key,value)
>M> tuples so they are much more like lists or tuples when it comes to
>M> comparisons.

>M> For example:

>>>>> l = [("a", 1), ("z", 2), ("k", 3)]
>>>>> l1 = l[:]
>>>>> l1[1] = ("z", 5)
>>>>> l < l1
>M> True

>M> But if you do:

>>>>> d = collections.OrderedDict(l)
>>>>> d1 = collections.OrderedDict(l1)

>M> You can't use <, <=, =>, or >, even though ordered dictionaries
>M> preserve the order and their items are just as comparable as those in
>M> a list or tuple of tuples.

But why should the order be as if the OrderedDict was a list of tuples.
A dict can be considered as a mapping and then you might want to treat
either the key or the value as contravariant (the key I guess). So there
is ambiguity. Why would the view as a list of tuples for the ordering be
the `natural' view? 

Maybe you may expect some kind of monotonicity such that d1<d2 implies
d1[x]<d2[x], but that doesn't work for d1 = {1:10, 2:20} and d2 = {1:15,
2:5}. So maybe there is only a partial ordering?

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rob.hooft at gmail.com  Thu Jul 16 05:25:27 2009
From: rob.hooft at gmail.com (rwwh)
Date: Thu, 16 Jul 2009 02:25:27 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com> 
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org> 
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org> 
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
	<006eb461$0$9711$c3e8da3@news.astraweb.com> 
	<mailman.2755.1246947020.8015.python-list@python.org>
	<006f13c9$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <1712a4da-fb9f-416e-9190-4da55fcc40ea@b14g2000yqd.googlegroups.com>

On Jul 7, 2:00?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Mon, 06 Jul 2009 22:18:20 -0700, Chris Rebert wrote:
> >> Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.
> [...]
> > Well, yes, but when would you apply it twice in a row?
>
> My point was that unary + isn't a no-op, and therefore neither is ++. For
> Decimal, I can't think why you'd want to apply ++x, but for other
> objects, who knows?
>
> Here's a toy example:
>
> >>> class Spam(str):
>
> ... ? ? def __pos__(self):
> ... ? ? ? ? return self.__class__("spam " + self)
> ...>>> s = Spam("")
> >>> ++++s
>
> 'spam spam spam spam '

Here's another toy example:

class Toy(int):
    def __init__(self, value):
        self._incrd = False
        int.__init__(self, value)

    def incrHalf(self):
        self._incrd = True

    def __pos__(self):
        if self._incrd:
            return self.__class__(self+1)
        else:
            p = self.__class__(self)
            p.incrHalf()
            return p

    def __add__(self, other):
        return self.__class__(int(self)+other)

nows122[126]~% python -i toy.py
>>> i=Toy(5)
>>> +i
5
>>> ++i
6
>>> +++i
6
>>> +i++i
10
>>> +(+i++i)
10
>>> (++i)++i
11


From clp2 at rebertia.com  Thu Jul 16 05:33:24 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 02:33:24 -0700
Subject: How to search this newsgroup by a python script.
In-Reply-To: <7c897lF26dea4U1@mid.dfncis.de>
References: <7c897lF26dea4U1@mid.dfncis.de>
Message-ID: <50697b2c0907160233j70ba360fv69f6f48e509b55aa@mail.gmail.com>

On Thu, Jul 16, 2009 at 2:12 AM, Helmut
Jarausch<jarausch at igpm.rwth-aachen.de> wrote:
> Hi,
>
> I haven't found anything with Google's group search, so let me
> ask it (again?).
>
> How can I search this newsgroup from within a Python script.
> (Perhaps by searching Google Groups or Gmane by some Python code.)

1. Generate URL of the form:
http://search.gmane.org/?query=foo&group=gmane.comp.python.general
where "foo" is the search terms, with proper URL escaping applied.
2. Fetch URL using urllib - http://docs.python.org/library/urllib.html
3. Parse resulting HTML page (e.g. using BeautifulSoup)
4. Extract desired information from search results using the parse tree.
5. ???
6. Profit!

Cheers,
Chris
-- 
http://blog.rebertia.com


From mail at timgolden.me.uk  Thu Jul 16 05:38:05 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 16 Jul 2009 10:38:05 +0100
Subject: How to search this newsgroup by a python script.
In-Reply-To: <50697b2c0907160233j70ba360fv69f6f48e509b55aa@mail.gmail.com>
References: <7c897lF26dea4U1@mid.dfncis.de>
	<50697b2c0907160233j70ba360fv69f6f48e509b55aa@mail.gmail.com>
Message-ID: <4A5EF4FD.7080708@timgolden.me.uk>

Chris Rebert wrote:
> On Thu, Jul 16, 2009 at 2:12 AM, Helmut
> Jarausch<jarausch at igpm.rwth-aachen.de> wrote:
>> Hi,
>>
>> I haven't found anything with Google's group search, so let me
>> ask it (again?).
>>
>> How can I search this newsgroup from within a Python script.
>> (Perhaps by searching Google Groups or Gmane by some Python code.)
> 
> 1. Generate URL of the form:
> http://search.gmane.org/?query=foo&group=gmane.comp.python.general
> where "foo" is the search terms, with proper URL escaping applied.
> 2. Fetch URL using urllib - http://docs.python.org/library/urllib.html
> 3. Parse resulting HTML page (e.g. using BeautifulSoup)
> 4. Extract desired information from search results using the parse tree.
> 5. ???
> 6. Profit!

Alternatively, you could do something with the mailing list archive:

  http://mail.python.org/pipermail/python-list/

The .gz files are gzipped mbox format so can be dropped into, eg,
Thunderbird for offline browsing, or searched with the email
package from the stdlib.

TJG


From user at example.net  Thu Jul 16 06:34:20 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 12:34:20 +0200
Subject: using timers to force an execution time
Message-ID: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>

hello.

based upon previuos suggestions, i tried to write a program in which i 
would like to have a certain code fragment to execute only for a 
specified amount of time (say 3 seconds), then bail out.

but i get the following:

$ cat tmr004.py
#!/usr/bin/python -u

import threading , time

e = threading.Event()
t = threading.Timer(3.0, e.set)
t.start()
print time.asctime(time.localtime(time.time()))
while not e.isSet():
     for repeat in range(10):
         print time.time()
         time.sleep(0.66)
print time.asctime(time.localtime(time.time()))
$ ./tmr004.py
Thu Jul 16 12:31:27 2009
1247740287.44
1247740288.1
1247740288.76
1247740289.42
1247740290.08
1247740290.74
1247740291.4
1247740292.06
1247740292.72
1247740293.38
Thu Jul 16 12:31:34 2009
$

see? the while body ran for about 7 seconds... i bet it has to do with 
the fact that the timer does not control inner loops... any suggestion?

$ python -V
Python 2.3.4
$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
$

bye


From contact at xavierho.com  Thu Jul 16 06:49:07 2009
From: contact at xavierho.com (Xavier Ho)
Date: Thu, 16 Jul 2009 18:49:07 +0800
Subject: using timers to force an execution time
In-Reply-To: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <2d56febf0907160349k7c4eaa50t42216ce85bcb1689@mail.gmail.com>

On Thu, Jul 16, 2009 at 6:34 PM, superpollo <user at example.net> wrote:

> hello.
>
> based upon previuos suggestions, i tried to write a program in which i
> would like to have a certain code fragment to execute only for a specified
> amount of time (say 3 seconds), then bail out.
>
> <snip>


> see? the while body ran for about 7 seconds... i bet it has to do with the
> fact that the timer does not control inner loops... any suggestion?
>
>
I'm guessing it has to do with a sleep of 0.66 seconds x 10 times = sleep
for 6.6 seconds, and then it checks for e.isSet().

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/5eb781e8/attachment.html>

From list at qtrac.plus.com  Thu Jul 16 06:50:25 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 03:50:25 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>
	<m2zlb5ugnh.fsf@cs.uu.nl>
Message-ID: <d3da1b04-0ebb-47a0-88aa-8d214cbf774b@24g2000yqm.googlegroups.com>

On 16 July, 10:21, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Mark <l... at qtrac.plus.com> (M) wrote:
> >M> You are right that it doesn't make sense to compare two dicts.
> >M> But OrderedDicts can be viewed logically as lists of (key,value)
> >M> tuples so they are much more like lists or tuples when it comes to
> >M> comparisons.
> >M> For example:
> >>>>> l = [("a", 1), ("z", 2), ("k", 3)]
> >>>>> l1 = l[:]
> >>>>> l1[1] = ("z", 5)
> >>>>> l < l1
> >M> True
> >M> But if you do:
> >>>>> d = collections.OrderedDict(l)
> >>>>> d1 = collections.OrderedDict(l1)
> >M> You can't use <, <=, =>, or >, even though ordered dictionaries
> >M> preserve the order and their items are just as comparable as those in
> >M> a list or tuple of tuples.
>
> But why should the order be as if the OrderedDict was a list of tuples.
> A dict can be considered as a mapping and then you might want to treat
> either the key or the value as contravariant (the key I guess). So there
> is ambiguity. Why would the view as a list of tuples for the ordering be
> the `natural' view?
>
> Maybe you may expect some kind of monotonicity such that d1<d2 implies
> d1[x]<d2[x], but that doesn't work for d1 = {1:10, 2:20} and d2 = {1:15,
> 2:5}. So maybe there is only a partial ordering?

OK, that seems to me to be a convincing argument against supporting
ordering.


From user at example.net  Thu Jul 16 06:56:50 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 12:56:50 +0200
Subject: turtle dump
Message-ID: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>

hi there.

is there a way to dump the content of a turtle window to a file or a 
file object?

bye


From list at qtrac.plus.com  Thu Jul 16 06:58:08 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 03:58:08 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
	<pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au>
Message-ID: <401967fb-c12e-4f63-8b05-6dffa0688028@a26g2000yqn.googlegroups.com>

On 16 July, 08:51, Steven D'Aprano
<ste... at REMOVE.THIS.cybersource.com.au> wrote:
> On Thu, 16 Jul 2009 00:30:26 -0700, Chris Rebert wrote:
> > On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<l... at qtrac.plus.com>
> > wrote:
> >> Hi,
>
> >> I'm just wondering why <, <=, >=, and > are not supported by
> >> collections.OrderedDict:
>
> >> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3))) d2 =
> >> ? ?>>> d1.copy()
> >> ? ?>>> d2["z"] = 4
> >> ? ?>>> d1 == d2
> >> ? ?False
> >> ? ?>>> d1 < d2
> >> ? ?Traceback (most recent call last):
> >> ? ?File "<pyshell#6>", line 1, in <module>
> >> ? ? ? ?d1 < d2
> >> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> >> It just seems to me that since the items in ordered dictionaries are
> >> ordered, it would make sense to do an item by item comparison from
> >> first to last item in exactly the same way that Python compares lists
> >> or tuples?
>
> > Use case? I'm curious.
>
> Surely it would be the same use case as for comparing two lists? There
> doesn't need to be a special "OrderedDict use case" beyond "an
> OrderedDict is just like a list of (key,value) tuples, but searches are
> faster".
>
> Or maybe not. If OrderedDicts are sequences as well as mappings, then we
> should be able to sort them. And that seems a bit much even for me.
>
> --
> Steven

One thing that I've just noticed is that you can use <, <=, >=, and >
with sets:

>>> s1 = {1,2,3}
>>> s2 = {1,2,4}
>>> s1 == s2
False
>>> s1 < s2
False
>>> s1 <= s2
False
>>> s2 < s1
False
>>> s2 <= s1
False
>>> s1 != s2
True

It seems a bit inconsistent that with sets you always get False when
using an ordering operator but with an ordered dict you get an
exception?


From list at qtrac.plus.com  Thu Jul 16 06:59:47 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 03:59:47 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
	<pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au> 
	<401967fb-c12e-4f63-8b05-6dffa0688028@a26g2000yqn.googlegroups.com>
Message-ID: <028e48c2-4a3a-4920-9a67-d9bb95714b4f@c36g2000yqn.googlegroups.com>

On 16 July, 11:58, Mark <l... at qtrac.plus.com> wrote:
> On 16 July, 08:51, Steven D'Aprano
>
>
>
> <ste... at REMOVE.THIS.cybersource.com.au> wrote:
> > On Thu, 16 Jul 2009 00:30:26 -0700, Chris Rebert wrote:
> > > On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<l... at qtrac.plus.com>
> > > wrote:
> > >> Hi,
>
> > >> I'm just wondering why <, <=, >=, and > are not supported by
> > >> collections.OrderedDict:
>
> > >> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3))) d2 =
> > >> ? ?>>> d1.copy()
> > >> ? ?>>> d2["z"] = 4
> > >> ? ?>>> d1 == d2
> > >> ? ?False
> > >> ? ?>>> d1 < d2
> > >> ? ?Traceback (most recent call last):
> > >> ? ?File "<pyshell#6>", line 1, in <module>
> > >> ? ? ? ?d1 < d2
> > >> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> > >> It just seems to me that since the items in ordered dictionaries are
> > >> ordered, it would make sense to do an item by item comparison from
> > >> first to last item in exactly the same way that Python compares lists
> > >> or tuples?
>
> > > Use case? I'm curious.
>
> > Surely it would be the same use case as for comparing two lists? There
> > doesn't need to be a special "OrderedDict use case" beyond "an
> > OrderedDict is just like a list of (key,value) tuples, but searches are
> > faster".
>
> > Or maybe not. If OrderedDicts are sequences as well as mappings, then we
> > should be able to sort them. And that seems a bit much even for me.
>
> > --
> > Steven
>
> One thing that I've just noticed is that you can use <, <=, >=, and >
> with sets:
>
> >>> s1 = {1,2,3}
> >>> s2 = {1,2,4}
> >>> s1 == s2
> False
> >>> s1 < s2
> False
> >>> s1 <= s2
> False
> >>> s2 < s1
> False
> >>> s2 <= s1
> False
> >>> s1 != s2
>
> True
>
> It seems a bit inconsistent that with sets you always get False when
> using an ordering operator but with an ordered dict you get an
> exception?

Ooops---disregard the above---I forgot that these do subset and
superset comparisions!


From akhilanger at gmail.com  Thu Jul 16 07:00:00 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 04:00:00 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <4a5ed587$0$1627$742ec2ed@news.sonic.net>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
Message-ID: <24514309.post@talk.nabble.com>


I have switched to python 3.1 , but now I am getting some syntax errors in
the code:

File "./customWikiExtractor.py", line 81
    __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1',
'&cent;'    :u'\u00A2',
                                            ^
SyntaxError: invalid syntax

line 81 is:
__char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1', '&cent;'   
:u'\u00A2',
                        '&pound;'  :u'\u00A3', '&curren;':u'\u00A4', '&yen;'    
:u'\u00A5',
                        '&brvbar;' :u'\u00A6', '&sect;'  :u'\u00A7', '&uml;'    
:u'\u00A8',
                        '&copy;'   :u'\u00A9', '&ordf;'  :u'\u00AA',
'&laquo;'   :u'\u00AB',
                        '&not;'    :u'\u00AC', '&shy;'   :u'\u00AD', '&reg;'    
:u'\u00AE',
                        '&macr;'   :u'\u00AF', '&deg;'   :u'\u00B0',
'&plusmn;'  :u'\u00B1',
                        '&sup2;'   :u'\u00B2', '&sup3;'  :u'\u00B3',
'&acute;'   :u'\u00B4',
                        '&micro;'  :u'\u00B5', '&para;'  :u'\u00B6',
'&middot;'  :u'\u00B7',
                        '&cedil;'  :u'\u00B8', '&sup1;'  :u'\u00B9',
'&ordm;'    :u'\u00BA',}

--Akhil


John Nagle-2 wrote:
> 
> akhil1988 wrote:
>> Sorry, it is sgmllib.py and not sgmmlib.py
> 
>     Oh, that bug again.  See
> 
> 	http://bugs.python.org/issue1651995
> 
> It's a bug in SGMLParser.  When Python 2.5 restricted ASCII to 0..127,
> SGMLParser needed to be modified, but wasn't.
> 
> I reported that bug in February 2007.  It was fixed in
> Python 2.6 and 3.0 on March 31, 2009.
> 
> 					John Nagle
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24514309.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From user at example.net  Thu Jul 16 07:01:34 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:01:34 +0200
Subject: using timers to force an execution time
In-Reply-To: <7c8fgbF26vgl2U1@mid.uni-berlin.de>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
Message-ID: <4a5f088f$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> What you can't achieve in python without major black magic hackery that is
> very dangerous is to terminate a thread while it is executing. Termination
> has to be co-operative.

i see. thanks a lot.

bye


From deets at nospam.web.de  Thu Jul 16 07:03:55 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:03:55 +0200
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <7c8fgbF26vgl2U1@mid.uni-berlin.de>

superpollo wrote:

> hello.
> 
> based upon previuos suggestions, i tried to write a program in which i
> would like to have a certain code fragment to execute only for a
> specified amount of time (say 3 seconds), then bail out.
> 
> but i get the following:
> 
> $ cat tmr004.py
> #!/usr/bin/python -u
> 
> import threading , time
> 
> e = threading.Event()
> t = threading.Timer(3.0, e.set)
> t.start()
> print time.asctime(time.localtime(time.time()))
> while not e.isSet():
>      for repeat in range(10):
>          print time.time()
>          time.sleep(0.66)
> print time.asctime(time.localtime(time.time()))
> $ ./tmr004.py
> Thu Jul 16 12:31:27 2009
> 1247740287.44
> 1247740288.1
> 1247740288.76
> 1247740289.42
> 1247740290.08
> 1247740290.74
> 1247740291.4
> 1247740292.06
> 1247740292.72
> 1247740293.38
> Thu Jul 16 12:31:34 2009
> $
> 
> see? the while body ran for about 7 seconds... i bet it has to do with
> the fact that the timer does not control inner loops... any suggestion?

Of course the inner loop isn't affected by the set event - how should it be,
if you don't check it.

if you rewrite it as this:

while True:
    for repeat in range(10):
        if e.isSet():
           break
        print time.time()
        time.sleep(.66)

it should terminate earlier.

What you can't achieve in python without major black magic hackery that is
very dangerous is to terminate a thread while it is executing. Termination
has to be co-operative.

Diez


From user at example.net  Thu Jul 16 07:04:08 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:04:08 +0200
Subject: using timers to force an execution time
In-Reply-To: <7c8fgbF26vgl2U1@mid.uni-berlin.de>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
Message-ID: <4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
>>see? the while body ran for about 7 seconds... i bet it has to do with
>>the fact that the timer does not control inner loops... any suggestion?
> 
> 
> Of course the inner loop isn't affected by the set event - how should it be,
> if you don't check it.
> 
> if you rewrite it as this:
> 
> while True:
>     for repeat in range(10):
>         if e.isSet():
>            break
>         print time.time()
>         time.sleep(.66)
> 
> it should terminate earlier.

so it seems almost impossible to allocate a certain amount of time to a 
code fragment *without* somehow rewriting its logic?

am i wrong?

bye


From akhilanger at gmail.com  Thu Jul 16 07:04:24 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 04:04:24 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <24514309.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<24514309.post@talk.nabble.com>
Message-ID: <24514367.post@talk.nabble.com>


Please click reply on the post and then read this reply in the editor.
Actually, some sequences have been replaced to their graphical form when
this post is published. So the python code is being displayed, what actually
it is not.

--Akhil



akhil1988 wrote:
> 
> I have switched to python 3.1 , but now I am getting some syntax errors in
> the code:
> 
> File "./customWikiExtractor.py", line 81
>     __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1',
> '&cent;'    :u'\u00A2',
>                                             ^
> SyntaxError: invalid syntax
> 
> line 81 is:
> __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1', '&cent;'   
> :u'\u00A2',
>                         '&pound;'  :u'\u00A3', '&curren;':u'\u00A4',
> '&yen;'     :u'\u00A5',
>                         '&brvbar;' :u'\u00A6', '&sect;'  :u'\u00A7',
> '&uml;'     :u'\u00A8',
>                         '&copy;'   :u'\u00A9', '&ordf;'  :u'\u00AA',
> '&laquo;'   :u'\u00AB',
>                         '&not;'    :u'\u00AC', '&shy;'   :u'\u00AD',
> '&reg;'     :u'\u00AE',
>                         '&macr;'   :u'\u00AF', '&deg;'   :u'\u00B0',
> '&plusmn;'  :u'\u00B1',
>                         '&sup2;'   :u'\u00B2', '&sup3;'  :u'\u00B3',
> '&acute;'   :u'\u00B4',
>                         '&micro;'  :u'\u00B5', '&para;'  :u'\u00B6',
> '&middot;'  :u'\u00B7',
>                         '&cedil;'  :u'\u00B8', '&sup1;'  :u'\u00B9',
> '&ordm;'    :u'\u00BA',}
> 
> --Akhil
> 
> 
> John Nagle-2 wrote:
>> 
>> akhil1988 wrote:
>>> Sorry, it is sgmllib.py and not sgmmlib.py
>> 
>>     Oh, that bug again.  See
>> 
>> 	http://bugs.python.org/issue1651995
>> 
>> It's a bug in SGMLParser.  When Python 2.5 restricted ASCII to 0..127,
>> SGMLParser needed to be modified, but wasn't.
>> 
>> I reported that bug in February 2007.  It was fixed in
>> Python 2.6 and 3.0 on March 31, 2009.
>> 
>> 					John Nagle
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24514367.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From deets at nospam.web.de  Thu Jul 16 07:08:40 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:08:40 +0200
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
Message-ID: <7c8fp8F26vgl2U2@mid.uni-berlin.de>

Diez B. Roggisch wrote:

> superpollo wrote:
> 
>> hello.
>> 
>> based upon previuos suggestions, i tried to write a program in which i
>> would like to have a certain code fragment to execute only for a
>> specified amount of time (say 3 seconds), then bail out.
>> 
>> but i get the following:
>> 
>> $ cat tmr004.py
>> #!/usr/bin/python -u
>> 
>> import threading , time
>> 
>> e = threading.Event()
>> t = threading.Timer(3.0, e.set)
>> t.start()
>> print time.asctime(time.localtime(time.time()))
>> while not e.isSet():
>>      for repeat in range(10):
>>          print time.time()
>>          time.sleep(0.66)
>> print time.asctime(time.localtime(time.time()))
>> $ ./tmr004.py
>> Thu Jul 16 12:31:27 2009
>> 1247740287.44
>> 1247740288.1
>> 1247740288.76
>> 1247740289.42
>> 1247740290.08
>> 1247740290.74
>> 1247740291.4
>> 1247740292.06
>> 1247740292.72
>> 1247740293.38
>> Thu Jul 16 12:31:34 2009
>> $
>> 
>> see? the while body ran for about 7 seconds... i bet it has to do with
>> the fact that the timer does not control inner loops... any suggestion?
> 
> Of course the inner loop isn't affected by the set event - how should it
> be, if you don't check it.
> 
> if you rewrite it as this:
> 
> while True:
>     for repeat in range(10):
>         if e.isSet():
>            break
>         print time.time()
>         time.sleep(.66)
> 
> it should terminate earlier.

This is of course wrong, remove the outer "while"

Diez


From user at example.net  Thu Jul 16 07:09:24 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:09:24 +0200
Subject: using timers to force an execution time
In-Reply-To: <7c8futF26vgl2U3@mid.uni-berlin.de>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
Message-ID: <4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
>>am i wrong?
> 
> 
> No, you are right, for threads that is. You can try & trick around with the
> trace-functionality of python, and some ctypes-based
> system-thread-module-tricks that are, as mentioned before, black-magic & a
> spinning gatling gun pointed to your very own lower extremities.
> 

OUCH.

> The only reliable way of terminating an asynchronous computation is to use
> processes, since python2.6 that's rather convenient with the
> multiprocessing-module. However, that imposes some limits to what you can
> do.

fair enough.

very helpful indeed.

bye


From deets at nospam.web.de  Thu Jul 16 07:11:41 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:11:41 +0200
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <7c8futF26vgl2U3@mid.uni-berlin.de>

superpollo wrote:

> Diez B. Roggisch wrote:
>> superpollo wrote:
>>>see? the while body ran for about 7 seconds... i bet it has to do with
>>>the fact that the timer does not control inner loops... any suggestion?
>> 
>> 
>> Of course the inner loop isn't affected by the set event - how should it
>> be, if you don't check it.
>> 
>> if you rewrite it as this:
>> 
>> while True:
>>     for repeat in range(10):
>>         if e.isSet():
>>            break
>>         print time.time()
>>         time.sleep(.66)
>> 
>> it should terminate earlier.
> 
> so it seems almost impossible to allocate a certain amount of time to a
> code fragment *without* somehow rewriting its logic?
> 
> am i wrong?

No, you are right, for threads that is. You can try & trick around with the
trace-functionality of python, and some ctypes-based
system-thread-module-tricks that are, as mentioned before, black-magic & a
spinning gatling gun pointed to your very own lower extremities.

The only reliable way of terminating an asynchronous computation is to use
processes, since python2.6 that's rather convenient with the
multiprocessing-module. However, that imposes some limits to what you can
do.

Diez



From deets at nospam.web.de  Thu Jul 16 07:15:04 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:15:04 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <7c8g58F26vgl2U4@mid.uni-berlin.de>

superpollo wrote:

> hi there.
> 
> is there a way to dump the content of a turtle window to a file or a
> file object?

Why should I want to dump a turtle? They are very benign creatures, dumping
them is going to hurt them needlessly.

Without a cheek-in-tongue: how are we supposed to know what a"turtle window"
is, how you create it, what features it uses? You need to give more
details, such as the module you are using, on what system that runs and so
forth.

Diez


From user at example.net  Thu Jul 16 07:18:51 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:18:51 +0200
Subject: turtle dump
In-Reply-To: <7c8g58F26vgl2U4@mid.uni-berlin.de>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
Message-ID: <4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
> 
> 
>>hi there.
>>
>>is there a way to dump the content of a turtle window to a file or a
>>file object?
> 
> 
> Why should I want to dump a turtle? They are very benign creatures, dumping
> them is going to hurt them needlessly.
> 

lol. ;-) the title was indeed supposed to stir a bit of curiosity upon 
the reader...

> Without a cheek-in-tongue: how are we supposed to know what a"turtle window"
> is, how you create it, what features it uses? You need to give more
> details, such as the module you are using, on what system that runs and so
> forth.

in fact i was looking for a *platform independent* way to draw into a 
graphics file (say, a postscript or a png) using the turtle module. so i 
understand that "dumping a window" is not a good expression... maybe 
"redirecting graphics commands to a file instead of a window"?

bye


From wuwei23 at gmail.com  Thu Jul 16 07:24:30 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 04:24:30 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com> 
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net> 
	<mailman.3213.1247742002.8015.python-list@python.org>
Message-ID: <63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>

On Jul 16, 9:00?pm, akhil1988 <akhilan... at gmail.com> wrote:
> I have switched to python 3.1 , but now I am getting some syntax errors in
> the code:

Python 3.x was a major release that endeavoured to clean up a number
of lingering issues with the language, the upshot being that it isn't
entirely backwards compatible with past versions. Unicode became the
default string type, which is what is causing the error here: the u-
prefix is no longer required (or even allowed).

However, Py3.x _does_ come with a handy tool for automatically
converting Python 2.x code to 3.x, called 2to3. One of the things it
should do is convert Py2.x unicode values into their correct
representation in 3.x.

With any luck, it should be able to convert the code you're using
entirely. Let us know how it goes.


From wuwei23 at gmail.com  Thu Jul 16 07:50:29 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 04:50:29 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it> 
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>

On Jul 16, 9:18?pm, superpollo <u... at example.net> wrote:
> lol. ;-) the title was indeed supposed to stir a bit of curiosity upon
> the reader...

Which isn't really useful when trying to obtain assistance... you want
certainty, not curiosity.

> in fact i was looking for a *platform independent* way to draw into a
> graphics file (say, a postscript or a png) using the turtle module. so i
> understand that "dumping a window" is not a good expression... maybe
> "redirecting graphics commands to a file instead of a window"?

You didn't actually answer Diez question. The turtle module is only a
recent (2.6/3.0) addition to Python and is probably obscure enough not
to have tracked across everyone's radar.

So _if_ you're talking about the standard lib turtle module, you're
not looking to 'dump a window', you're looking to write the contents
of turtle.Canvas to file. Canvas only supports writing to postscript,
so you'll have to do something like this (untested):

import turtle
screen = turtle.Screen()
# go go gadget turtle...
screen._canvas.postscript(file='turtle.ps')

Or it may be open('turtle.ps','w').write(screen._canvas.postscript
())... I couldn't find a definitive answer. Try looking through the Tk
docs, it should be covered there.

Note that this is a postscript _text_ file, so you'll also need to
find something to render it with.

Hope this helps point you in the right direction.


From user at example.net  Thu Jul 16 08:11:07 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 14:11:07 +0200
Subject: turtle dump
In-Reply-To: <77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
Message-ID: <4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>

alex23 wrote:
> On Jul 16, 9:18 pm, superpollo <u... at example.net> wrote:
> 
>>lol. ;-) the title was indeed supposed to stir a bit of curiosity upon
>>the reader...
> 
> 
> Which isn't really useful when trying to obtain assistance... you want
> certainty, not curiosity.
> 

ok. my bad.

> 
>>in fact i was looking for a *platform independent* way to draw into a
>>graphics file (say, a postscript or a png) using the turtle module. so i
>>understand that "dumping a window" is not a good expression... maybe
>>"redirecting graphics commands to a file instead of a window"?
> 
> 
> You didn't actually answer Diez question. The turtle module is only a
> recent (2.6/3.0) addition to Python and is probably obscure enough not
> to have tracked across everyone's radar.
> 

actually i am still using 2.3.4, which means that...

> screen = turtle.Screen()

... is not possible

> 
> Hope this helps point you in the right direction.

it certainly did, tahnks.

bye


From bearophileHUGS at lycos.com  Thu Jul 16 08:22:22 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 16 Jul 2009 05:22:22 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <267d74e2-97ce-477c-a39b-022fc4f82bd3@i6g2000yqj.googlegroups.com>

Superchicken:
> is there a way to dump the content of a turtle window to a file or a file object?

A possible low-tech solution is to append to a list the sequence of
your plotting commands (using a decorator too, even, something like
the logging decorator), and then save all of them at the end into a
text file :-)

Bye,
bearophile


From piet at cs.uu.nl  Thu Jul 16 08:39:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 14:39:54 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
Message-ID: <m2ocrkvm1x.fsf@cs.uu.nl>

>>>>> mheavner <miheavner at gmail.com> (m) wrote:

>m> I'm using multiprocessing to spawn several subprocesses, each of which
>m> uses a very large data structure (making it impractical to pass it via
>m> pipes / pickling). I need to allocate this structure once when the
>m> process is created and have it remain in memory for the duration of
>m> the process. The way the multiprocessing module is set up, only the
>m> 'run' method runs within the subprocess - so creating a wrapper class
>m> with a constructor that allocates the structure in __init__ will not
>m> work, as far as I know, as this will still be within the parent
>m> process.

>m> If I were working in C/C++, I would declare the variable "static"
>m> within the function body - is there any way with the multiprocessing
>m> module to have persistent data members within subprocesses?

>m> Any ideas??

Your post is not entirely clear. Is `the process' the same as `the
subprocess'? 

Assuming it is, what is the problem? You can create the datastructure
first thing in the run method can't you?

Like this:

from multiprocessing import Process
from time import sleep
from random import random

class MyProcess(Process):

    def __init__(self, number):
        self.number = number
        Process.__init__(self)

    def run(self):
        print "Process %s started" % self.number
        self.data = range(self.number * 100000, (self.number + 1) * 100000)
        self.doit()

    def doit(self):
        for i in range(5):
            sleep(3 * random())
            self.data[i] += i
            print self.data[i]

processes = []
for k in range(10):
    p = MyProcess(k)
    p.start()
    processes.append(p)


for p in processes:
    p.join()

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From albert at spenarnc.xs4all.nl  Thu Jul 16 08:45:27 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 16 Jul 2009 12:45:27 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <kmvkrr.1hc@spenarnc.xs4all.nl>

In article <h2l36k$q5l$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>
>I'm will be teaching a programming class to novices, and I've run
>into a clear conflict between two of the principles I'd like to
>teach: code clarity vs. code reuse.  I'd love your opinion about
>it.
>
<SNIP>
>
>This seemed straightforward enough, until I realized that, to be
>useful to my students in their homework, this _binary_search function
>had to handle the case in which the passed function was monotonically
>decreasing in the specified interval...
>
<SNIP>
>
>Here's the rub: the code above is more general (hence more reusable)
>by virtue of this trick with the sense parameter, but it is also
>a bit harder to understand.
>
>This not an unusual situation.  I find that the processing of
>abstracting out common logic often results in code that is harder
>to read, at least for the uninitiated...

Yes, of course. You're teaching, say, green belt programmers.
Good reusable code requires a fifth dan. You may not be up to it
yourself (no offense intended), let alone your students.

Writing a reusable binary search is a very different assignment
from being able to code/use it in a concrete example.

Their choice must be between *writing* a one-off binary search,
versus *using* a brilliantly code, brilliantly documented
binary search that has been given beforehand.

Even assuming the reusable code is perfect in all sense, reusing may
be more effort than writing from scratch.
Then *you* have to explain them about the benefits of reuse.
(The other benefits, of course.)

>
>I'd love to know your opinions on this.

You're welcome.

>kj

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From __peter__ at web.de  Thu Jul 16 08:46:40 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 16 Jul 2009 14:46:40 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
Message-ID: <h3n7fb$b0h$00$1@news.t-online.com>

superpollo wrote:

> alex23 wrote:
>> On Jul 16, 9:18 pm, superpollo <u... at example.net> wrote:
>> 
>>>lol. ;-) the title was indeed supposed to stir a bit of curiosity upon
>>>the reader...
>> 
>> 
>> Which isn't really useful when trying to obtain assistance... you want
>> certainty, not curiosity.
>> 
> 
> ok. my bad.
> 
>> 
>>>in fact i was looking for a *platform independent* way to draw into a
>>>graphics file (say, a postscript or a png) using the turtle module. so i
>>>understand that "dumping a window" is not a good expression... maybe
>>>"redirecting graphics commands to a file instead of a window"?
>> 
>> 
>> You didn't actually answer Diez question. The turtle module is only a
>> recent (2.6/3.0) addition to Python and is probably obscure enough not
>> to have tracked across everyone's radar.
>> 
> 
> actually i am still using 2.3.4, which means that...
> 
>> screen = turtle.Screen()
> 
> ... is not possible

Tested on 2.4:

>>> import turtle
>>> turtle.reset()
>>> for i in range(4):
...     turtle.forward(50)
...     turtle.right(90)
...
>>> turtle._canvas.postscript(file="tmp.ps")
''

I think the big rewrite has happened in 2.6, so the above should also work 
in 2.3.

Peter



From user at example.net  Thu Jul 16 09:07:26 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 15:07:26 +0200
Subject: turtle dump
In-Reply-To: <h3n7fb$b0h$00$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com>
Message-ID: <4a5f260f$0$18931$4fafbaef@reader2.news.tin.it>

Peter Otten wrote:
> Tested on 2.4:
> 
> 
>>>>import turtle
>>>>turtle.reset()
>>>>for i in range(4):
> 
> ...     turtle.forward(50)
> ...     turtle.right(90)
> ...
> 
>>>>turtle._canvas.postscript(file="tmp.ps")
> 
> ''
> 
> I think the big rewrite has happened in 2.6, so the above should also work 
> in 2.3.
> 
> Peter
> 

mr otten, you are great.

bye


From hartley79 at gmail.com  Thu Jul 16 09:10:35 2009
From: hartley79 at gmail.com (hartley)
Date: Thu, 16 Jul 2009 06:10:35 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>
Message-ID: <a98dfff2-eefb-4fa8-909d-78851e4180fe@y19g2000yqy.googlegroups.com>

/* the first telling */
(...)
/* the third telling */
(...)
/* the third telling */


-
If you had loosened up on the sarcasm I would probably have read what
you wrote more thoroughly instead of just skimming through it. Thanks
for the help, but you should seriously consider doing something with
your patronizing attitude.

HTH,
Hartley


From hartley79 at gmail.com  Thu Jul 16 09:13:09 2009
From: hartley79 at gmail.com (hartley)
Date: Thu, 16 Jul 2009 06:13:09 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>
Message-ID: <0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>

/* the first telling */
(...)
/* the second telling */
(...)
/* the third telling */

-
If you had loosened up on the sarcasm I would probably have read what
you wrote more thoroughly instead of just skimming through it. Thanks
for the help, but you should seriously consider doing something with
your patronizing attitude.

HTH,
Hartley


From albert at spenarnc.xs4all.nl  Thu Jul 16 09:15:59 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 16 Jul 2009 13:15:59 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2uhcb$blq$1@panix3.panix.com>
	<006eb26f$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2814.1247032175.8015.python-list@python.org>
Message-ID: <kmvm6n.1na@spenarnc.xs4all.nl>

In article <mailman.2814.1247032175.8015.python-list at python.org>,
Dennis Lee Bieber  <wlfraed at ix.netcom.com> wrote:
>On 07 Jul 2009 05:05:12 GMT, Steven D'Aprano
><steve at REMOVE-THIS-cybersource.com.au> declaimed the following in
>gmane.comp.python.general:
>
>> Paraphrasing the Collins Dictionary of Mathematics:
>>
>> opposite sense. Sense is also used to distinguish clockwise and anti-
>> clockwise.
>>
>       Which, I believe, is the only usage I've encountered of it... In
>regards to quantum spin states in such things as Scientific American
>(though that magazine has either gone down hill in the last 30 years, or
>my expectations have gone up... Current issues read like the first years
>of Discover magazine)

I dropped my subscription when power was expressed in multiples
of US hair dryers. (I could calculate that back, and was appalled
by the energy wastage of US hair dryers. ;-) )

>--
>       Wulfraed        Dennis Lee Bieber               KD6MOG

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From matt.dubins at sympatico.ca  Thu Jul 16 09:17:27 2009
From: matt.dubins at sympatico.ca (inkhorn)
Date: Thu, 16 Jul 2009 06:17:27 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com> 
	<mailman.3073.1247547957.8015.python-list@python.org>
	<22fa2fe9-899b-407a-8e3c-49f29c86fa59@r33g2000yqn.googlegroups.com>
Message-ID: <b1be8010-d13b-49a4-91df-6dc51969f8c2@q11g2000yqi.googlegroups.com>

Hi all,

This was more a question of programming aesthetics for me than one of
great practical significance.  I was looking to perform a certain
function on files in a directory so long as those files weren't found
in certain standard directories.  In other words, I was using os.walk
() to get multiple root directory strings, and the lists of files in
each directory.  The function was to be performed on those files, so
long as certain terms weren't in the root directory string.

In actuality, I could have stuck with the helper function I created,
but I'm always curious to see how well multiple lines of code can turn
into fewer lines of code in python and retain the same functional
value :)

Matt

On Jul 15, 6:46?am, denis <denis-bz... at t-online.de> wrote:
> Sure, Aho-Corasick is fast for fixedstrings; but without real
> numbers / a concrete goal
>
> > > Matt, how many words are you looking for, in how long a string ?
>
> a simple solution is good enough, satisficing. ?Matt asked "how to
> make that function look nicer?"
> but "nice" has many dimensions -- bicycles are nice for some tasks,
> Ferraris for others.
>
> Bythewayhttp://en.wikipedia.org/wiki/Aho-Corasick_algorithmhas a
> link to a Python implementation,
> alsohttp://en.wikipedia.org/wiki/Worse_is_Betteris fun.



From motoom at xs4all.nl  Thu Jul 16 09:17:47 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Thu, 16 Jul 2009 15:17:47 +0200
Subject: turtle dump
In-Reply-To: <h3n7fb$b0h$00$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com>
Message-ID: <4A5F287B.2000503@xs4all.nl>


I got success with the following code (python 2.6.2):

import turtle
turtle.reset()
for i in range(4):
    turtle.forward(50)
    turtle.right(90)
can=turtle.getscreen().getcanvas()
can.postscript(file="tmp.ps")


-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From miheavner at gmail.com  Thu Jul 16 09:18:43 2009
From: miheavner at gmail.com (mheavner)
Date: Thu, 16 Jul 2009 06:18:43 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
Message-ID: <93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>

On Jul 16, 8:39?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> mheavner <miheav... at gmail.com> (m) wrote:
> >m> I'm using multiprocessing to spawn several subprocesses, each of which
> >m> uses a very large data structure (making it impractical to pass it via
> >m> pipes / pickling). I need to allocate this structure once when the
> >m> process is created and have it remain in memory for the duration of
> >m> the process. The way the multiprocessing module is set up, only the
> >m> 'run' method runs within the subprocess - so creating a wrapper class
> >m> with a constructor that allocates the structure in __init__ will not
> >m> work, as far as I know, as this will still be within the parent
> >m> process.
> >m> If I were working in C/C++, I would declare the variable "static"
> >m> within the function body - is there any way with the multiprocessing
> >m> module to have persistent data members within subprocesses?
> >m> Any ideas??
>
> Your post is not entirely clear. Is `the process' the same as `the
> subprocess'?
>
> Assuming it is, what is the problem? You can create the datastructure
> first thing in the run method can't you?
>
> Like this:
>
> from multiprocessing import Process
> from time import sleep
> from random import random
>
> class MyProcess(Process):
>
> ? ? def __init__(self, number):
> ? ? ? ? self.number = number
> ? ? ? ? Process.__init__(self)
>
> ? ? def run(self):
> ? ? ? ? print "Process %s started" % self.number
> ? ? ? ? self.data = range(self.number * 100000, (self.number + 1) * 100000)
> ? ? ? ? self.doit()
>
> ? ? def doit(self):
> ? ? ? ? for i in range(5):
> ? ? ? ? ? ? sleep(3 * random())
> ? ? ? ? ? ? self.data[i] += i
> ? ? ? ? ? ? print self.data[i]
>
> processes = []
> for k in range(10):
> ? ? p = MyProcess(k)
> ? ? p.start()
> ? ? processes.append(p)
>
> for p in processes:
> ? ? p.join()
>
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

'The process' refers to the subprocess. I could do as you say, load
the data structure each time, but the problem is that takes a
considerable amount of time compared to the the actual computation
with the data it contains. I'm using these processes within a loop as
follows:

         # Don't recreate processes or Queues
         pop1 = Queue()
         pop2 = Queue()
         pop_out = Queue()
         p1 = CudaProcess(0, args=(costf,pop1,pop_out))
         p2 = CudaProcess(1, args=(costf,pop2,pop_out))

         # Main loop
         for i in range(maxiter):
                 print 'ITERATION: '+str(i)
                 if log != None:
                         l = open(log,'a')
                 l.write('Iteration: '+str(i)+'\n')
                 l.close()

                 # Split population in two
                 pop1.putmany(pop[0:len(pop)/2])
                 pop2.putmany(pop[len(pop)/2:len(pop)])

                 # Start two processes
                 if not p1.isAlive():
                         p1.start()
                         print 'started %s'%str(p1.getPid())
                 else:
                         p1.run()
                 if not p2.isAlive():
                         p2.start()
                         print 'started %s'%str(p2.getPid())
                 else:
                         p2.run()
                 .
                 .
                 .

So I'd like to load that data into memory once and keep there as long
as the process is alive (ideally when the subprocess is created,
storing some sort of pointer to it), rather than loading it each time
run is called for a process within the loop. Could be my CudaProcess
class - I'll check out what Diez suggested and post back.


From albert at spenarnc.xs4all.nl  Thu Jul 16 09:19:08 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 16 Jul 2009 13:19:08 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<CuH4m.3259$ze1.429@news-server.bigpond.net.au>
Message-ID: <kmvmbw.1ot@spenarnc.xs4all.nl>

In article <CuH4m.3259$ze1.429 at news-server.bigpond.net.au>,
Lie Ryan  <lie.1296 at gmail.com> wrote:
>Steven D'Aprano wrote:
>> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
>>
>>> When people are fighting over things like `sense`, although sense may
>>> not be strictly wrong dictionary-wise, it smells of something burning...
>>
>> That would be my patience.
>>
>> I can't believe the direction this discussion has taken.
>
>Me neither.
>
>> Anybody sensible
>> would be saying "Oh wow, I've just learned a new meaning to the word,
>> that's great, I'm now less ignorant than I was a minute ago". But oh no,
>> we mustn't use a standard meaning to a word, heaven forbid we disturb
>> people's ignorance by teaching them something new.
>
>A meaning of a word is meaningless if nobody apart the writer
>understands it. The purpose of code is 1) to communicate with the

Exactly. And the OP teaches to scientist. They know sense in that
meaning. Maybe you don't, but that is irrelevant.

<SNIP>

Groetjes Albert.

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From anthony.tolle at gmail.com  Thu Jul 16 09:23:57 2009
From: anthony.tolle at gmail.com (Anthony Tolle)
Date: Thu, 16 Jul 2009 06:23:57 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<ae7da03e-5852-4dbe-b11c-37f4afc32dbe@n11g2000yqb.googlegroups.com> 
	<7x3a8xwjq5.fsf@ruckus.brouhaha.com>
Message-ID: <bbdf5d20-4354-4f9d-ab2e-fbd0b33d8233@h21g2000yqa.googlegroups.com>

On Jul 15, 8:32?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Among other things, that uses quadratic time! ?Why do you want to keep
> popping items from that list instead of iterating through it anyway?
>
> Anyway, I think you wrote something close to this:
> ...

Very true!  I didn't think about the problems with pop().  I was using
it as a shortcut for pulling off the first operand.  I forgot that if
you start with an initial operand of "False", the result will be the
same (0 xor X = X)

While I'm not sure how useful it would be, here's a version of the
first function that returns one of the operands (ala AND and OR),
except in the case where there is an even number of True elements,
where it returns False:

def xor(*operands):
    r, rprime = False, False
    for x in operands:
        xprime = bool(x)
        if rprime:
            if xprime:
                r, rprime = False, False
        else:
            r, rprime = x, xprime
    return r

>>> xor(0, 0)
0
>>> xor(0, 1)
1
>>> xor(1, 0)
1
>>> xor(1, 1)
False
>>> xor(0, 1, 2)
False
>>> xor(0, 1, 2, 3)
3
>>> xor(None, [])
[]


From nick at craig-wood.com  Thu Jul 16 09:29:59 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 16 Jul 2009 08:29:59 -0500
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
	<4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <slrnh5u88d.604.nick@irishsea.home.craig-wood.com>

superpollo <user at example.net> wrote:
>  Diez B. Roggisch wrote:
> > superpollo wrote:
> >>am i wrong?
> > 
> > 
> > No, you are right, for threads that is. You can try & trick around with the
> > trace-functionality of python, and some ctypes-based
> > system-thread-module-tricks that are, as mentioned before, black-magic & a
> > spinning gatling gun pointed to your very own lower extremities.
> > 
> 
>  OUCH.
> 
> > The only reliable way of terminating an asynchronous computation is to use
> > processes, since python2.6 that's rather convenient with the
> > multiprocessing-module. However, that imposes some limits to what you can
> > do.
> 
>  fair enough.

Or if you are on unix you can use signals...

It is probably just about acceptable to raise an exception in a signal
handler like this code does.

import signal, os, time

class TimeOut(Exception):
    """Thrown on alarm"""
    pass

def sig_alarm(signum, frame):
    raise TimeOut()

def time_out(t, fn, *args, **kwargs):
    """Calls fn with the args and kwargs returning its result or raising a TimeOut exception if it doesn't complete within t seconds"""

    # Turn alarm off and read old value
    old_alarm = signal.alarm(0)
    # Install new handler remembering old
    old_handler = signal.signal(signal.SIGALRM, sig_alarm)
    # Set the timer going
    signal.alarm(t)

    try:
        rc = fn(*args, **kwargs)
    finally:
        # Restore the old handler
        signal.signal(signal.SIGALRM, old_handler)
        signal.alarm(0)          

def test():
    for repeat in range(10):
        print time.time()
        time.sleep(0.66)

if __name__ == "__main__":
    try:
        time_out(3, test)
    except TimeOut:
        print "timed out"

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From inky788 at gmail.com  Thu Jul 16 09:32:34 2009
From: inky788 at gmail.com (Inky 788)
Date: Thu, 16 Jul 2009 06:32:34 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
Message-ID: <34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>

On Jul 10, 7:35?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> walterbyrd <walterb... at iname.com> writes:
> > I believe Guido himself has said that all indentions should be four
> > spaces - no tabs.
>
> Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
> with a simple imperative::
>
> ? ? Use 4 spaces per indentation level.

That actually sounds pretty weird. "Don't do {foo}. Really, I mean
*really* don't do {foo}. Oh, also, the interpreter allows you to do
{foo}. But don't do it! I mean it!".

Very ... perlish, if you ask me.

I realize that a small portion of the community likes the tabs.
They're sold on the tabs. They like the tabs. But tabs are an archaic
holdover from an era when typewriters had physical tabstops on them.
Actually, after *that* they're a holdover from a program called `make`
whose designers unfortunately decided to use tab "characters" to
prefix commands. The tab is vestigial. Your text editor can treat 4
consecutive spaces as a unit if you wish. Let tabs go away. Stop using
them. If your editor keeps irrationally inserting them, make it stop.


From miheavner at gmail.com  Thu Jul 16 09:32:47 2009
From: miheavner at gmail.com (mheavner)
Date: Thu, 16 Jul 2009 06:32:47 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <d74eebed-7127-4902-8469-a67373994ed3@b15g2000yqd.googlegroups.com>

On Jul 16, 9:18?am, mheavner <miheav... at gmail.com> wrote:
> On Jul 16, 8:39?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>
>
>
> > >>>>> mheavner <miheav... at gmail.com> (m) wrote:
> > >m> I'm using multiprocessing to spawn several subprocesses, each of which
> > >m> uses a very large data structure (making it impractical to pass it via
> > >m> pipes / pickling). I need to allocate this structure once when the
> > >m> process is created and have it remain in memory for the duration of
> > >m> the process. The way the multiprocessing module is set up, only the
> > >m> 'run' method runs within the subprocess - so creating a wrapper class
> > >m> with a constructor that allocates the structure in __init__ will not
> > >m> work, as far as I know, as this will still be within the parent
> > >m> process.
> > >m> If I were working in C/C++, I would declare the variable "static"
> > >m> within the function body - is there any way with the multiprocessing
> > >m> module to have persistent data members within subprocesses?
> > >m> Any ideas??
>
> > Your post is not entirely clear. Is `the process' the same as `the
> > subprocess'?
>
> > Assuming it is, what is the problem? You can create the datastructure
> > first thing in the run method can't you?
>
> > Like this:
>
> > from multiprocessing import Process
> > from time import sleep
> > from random import random
>
> > class MyProcess(Process):
>
> > ? ? def __init__(self, number):
> > ? ? ? ? self.number = number
> > ? ? ? ? Process.__init__(self)
>
> > ? ? def run(self):
> > ? ? ? ? print "Process %s started" % self.number
> > ? ? ? ? self.data = range(self.number * 100000, (self.number + 1) * 100000)
> > ? ? ? ? self.doit()
>
> > ? ? def doit(self):
> > ? ? ? ? for i in range(5):
> > ? ? ? ? ? ? sleep(3 * random())
> > ? ? ? ? ? ? self.data[i] += i
> > ? ? ? ? ? ? print self.data[i]
>
> > processes = []
> > for k in range(10):
> > ? ? p = MyProcess(k)
> > ? ? p.start()
> > ? ? processes.append(p)
>
> > for p in processes:
> > ? ? p.join()
>
> > --
> > Piet van Oostrum <p... at cs.uu.nl>
> > URL:http://pietvanoostrum.com[PGP8DAE142BE17999C4]
> > Private email: p... at vanoostrum.org
>
> 'The process' refers to the subprocess. I could do as you say, load
> the data structure each time, but the problem is that takes a
> considerable amount of time compared to the the actual computation
> with the data it contains. I'm using these processes within a loop as
> follows:
>
> ? ? ? ? ?# Don't recreate processes or Queues
> ? ? ? ? ?pop1 = Queue()
> ? ? ? ? ?pop2 = Queue()
> ? ? ? ? ?pop_out = Queue()
> ? ? ? ? ?p1 = CudaProcess(0, args=(costf,pop1,pop_out))
> ? ? ? ? ?p2 = CudaProcess(1, args=(costf,pop2,pop_out))
>
> ? ? ? ? ?# Main loop
> ? ? ? ? ?for i in range(maxiter):
> ? ? ? ? ? ? ? ? ?print 'ITERATION: '+str(i)
> ? ? ? ? ? ? ? ? ?if log != None:
> ? ? ? ? ? ? ? ? ? ? ? ? ?l = open(log,'a')
> ? ? ? ? ? ? ? ? ?l.write('Iteration: '+str(i)+'\n')
> ? ? ? ? ? ? ? ? ?l.close()
>
> ? ? ? ? ? ? ? ? ?# Split population in two
> ? ? ? ? ? ? ? ? ?pop1.putmany(pop[0:len(pop)/2])
> ? ? ? ? ? ? ? ? ?pop2.putmany(pop[len(pop)/2:len(pop)])
>
> ? ? ? ? ? ? ? ? ?# Start two processes
> ? ? ? ? ? ? ? ? ?if not p1.isAlive():
> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.start()
> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p1.getPid())
> ? ? ? ? ? ? ? ? ?else:
> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.run()
> ? ? ? ? ? ? ? ? ?if not p2.isAlive():
> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.start()
> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p2.getPid())
> ? ? ? ? ? ? ? ? ?else:
> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.run()
> ? ? ? ? ? ? ? ? ?.
> ? ? ? ? ? ? ? ? ?.
> ? ? ? ? ? ? ? ? ?.
>
> So I'd like to load that data into memory once and keep there as long
> as the process is alive (ideally when the subprocess is created,
> storing some sort of pointer to it), rather than loading it each time
> run is called for a process within the loop. Could be my CudaProcess
> class - I'll check out what Diez suggested and post back.

Essentially, I'd like to "sneak" that allocation in somewhere after
the fork is done (in start()) in the context of the subprocess,
holding a pointer to that structure, but before all of the run() calls
are done


From emile at fenx.com  Thu Jul 16 09:34:34 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 06:34:34 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5EEDAE.3040605@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com>
Message-ID: <h3na3s$qjr$1@ger.gmane.org>

On 7/16/2009 2:06 AM Jean-Michel Pichavant said...
> Ok then, why "or" does not return True, if the first element is 
> considered True ? Why returning the element itself. Any reason for that 
> ? Because it's confusing, maybe people used to that logic find it 
> obvious, but I really don't.

For example, I sometimes use it to set defaults:

daysInAdvance = int(inputVar) or 25

Emile



From wuwei23 at gmail.com  Thu Jul 16 09:43:20 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 06:43:20 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it> 
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it> 
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com> 
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
Message-ID: <e0f4708f-1717-4420-8d5b-87b3c1d5a82a@b25g2000prb.googlegroups.com>

On Jul 16, 10:11?pm, superpollo <u... at example.net> wrote:
> actually i am still using 2.3.4, which means that...
>
> > screen = turtle.Screen()
>
> ... is not possible

Ah, sorry about that. My belief that turtle was a new module was based
on a line from http://us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-PyCon2007.pdf

   Since Python 2.6/3.0, Python has had a new turtle module.

At which point I stopped reading and missed the following line:

   Its development was based entirely on the previous one.

In my defence, I _had_ been drinking.

Thankfully Peter stepped up with a more appropriate solution, and
Michiel pointed out the more suitable API calls over dealing directly
with the underlying implementation :) Good work guys!


From p.f.moore at gmail.com  Thu Jul 16 09:46:13 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Thu, 16 Jul 2009 14:46:13 +0100
Subject: using timers to force an execution time
In-Reply-To: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <79990c6b0907160646n58163a3fx1577951dab64215d@mail.gmail.com>

2009/7/16 superpollo <user at example.net>:
> hello.
>
> based upon previuos suggestions, i tried to write a program in which i would
> like to have a certain code fragment to execute only for a specified amount
> of time (say 3 seconds), then bail out.
>
> but i get the following:
>
> $ cat tmr004.py
> #!/usr/bin/python -u
>
> import threading , time
>
> e = threading.Event()
> t = threading.Timer(3.0, e.set)
> t.start()
> print time.asctime(time.localtime(time.time()))
> while not e.isSet():
> ? ?for repeat in range(10):
> ? ? ? ?print time.time()
> ? ? ? ?time.sleep(0.66)
> print time.asctime(time.localtime(time.time()))
> $ ./tmr004.py
> Thu Jul 16 12:31:27 2009
> 1247740287.44
> 1247740288.1
> 1247740288.76
> 1247740289.42
> 1247740290.08
> 1247740290.74
> 1247740291.4
> 1247740292.06
> 1247740292.72
> 1247740293.38
> Thu Jul 16 12:31:34 2009
> $
>
> see? the while body ran for about 7 seconds... i bet it has to do with the
> fact that the timer does not control inner loops... any suggestion?

Clearly, this isn't what you are actually trying to do. For this case,
your event is getting set when you expect, but your main thread does
not check the event often enough to let it stop in a timely manner.

To fix this, remove the inner "for repeat in range(10)" loop. But I
assume that your "real" code isn't something that you can fix this
easily. If you describe your real requirement, it may be possible to
give you a better answer. (But that answer will almost certainly not
be a way of interrupting one thread from another - that's not really
possible with Python - but rather a way of achieving your goal without
*needing* to interrupt one thread from another).

Paul.

PS If you really must interrupt one thread from another, you can use C
code (or ctypes) to call the PyThreadState_SetAsyncExc API. But I'm
not going to tell you how, as it's almost certainly *not* what you
want to do in practice :-)


From user at example.net  Thu Jul 16 09:46:41 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 15:46:41 +0200
Subject: using timers to force an execution time
In-Reply-To: <slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
	<4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>
	<slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
Message-ID: <4a5f2f43$0$18933$4fafbaef@reader2.news.tin.it>

Nick Craig-Wood wrote:
> superpollo <user at example.net> wrote:
 > ...
> Or if you are on unix you can use signals...
>
> It is probably just about acceptable to raise an exception in a signal
> handler like this code does.
> 
 > ...

neat!


From icanbob at gmail.com  Thu Jul 16 09:50:52 2009
From: icanbob at gmail.com (bobicanprogram)
Date: Thu, 16 Jul 2009 06:50:52 -0700 (PDT)
Subject: Passing handlers between bound c++ libs
References: <3e7b0717-a665-4f42-b7bd-7a99d59258c4@m11g2000yqh.googlegroups.com>
Message-ID: <a61c8b52-8a98-41e0-921e-f3dd5d40e239@k6g2000yqn.googlegroups.com>

On Jul 14, 7:07 pm, Freyr <freyr.magnus... at gmail.com> wrote:
> I have a python bound physics library that uses handler to process
> events. The passing of handlers between c++ and python causes a huge
> overhead slowing down the process.  Can I implement a handler in my
> custom python bound c++ lib B and pass it to blackbox python bound c++
> lib A so that A would call B directly without passing through the
> python layer?  Or to phrase the question differently:  Can I pass a
> handler from B through python to A so that A will invoke B with out
> calling into python code?


Depending on your exact configuration you may be able to wrap that C++
library using the SIMPL toolkit and get at your data with a
message.    There is some "hello world" demo code here:

http://www.icanprogram.com/06py/main.html

bob


From user at example.net  Thu Jul 16 09:51:59 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 15:51:59 +0200
Subject: using timers to force an execution time
In-Reply-To: <slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
	<4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>
	<slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
Message-ID: <4a5f3080$0$18933$4fafbaef@reader2.news.tin.it>

Nick Craig-Wood wrote:
 > ...
> import signal, os, time
> ...
importing os is useless of course...


From jeanmichel at sequans.com  Thu Jul 16 09:53:45 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 16 Jul 2009 15:53:45 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3na3s$qjr$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>
	<h3na3s$qjr$1@ger.gmane.org>
Message-ID: <4A5F30E9.1000404@sequans.com>

Emile van Sebille wrote:
> On 7/16/2009 2:06 AM Jean-Michel Pichavant said...
>> Ok then, why "or" does not return True, if the first element is 
>> considered True ? Why returning the element itself. Any reason for 
>> that ? Because it's confusing, maybe people used to that logic find 
>> it obvious, but I really don't.
>
> For example, I sometimes use it to set defaults:
>
> daysInAdvance = int(inputVar) or 25
>
> Emile
>
Sure this looks like an elegant way to set default values and I will use 
this form , but I'm not sure this justifies by itself the trickery. 
Python has extended the algebra definition of "or" and "and" top any 
type, but it is so unintuitive (I'm no LISP programmer). I think than 
using the short-circuiting mechanism of bool operators along with the 
python tricks is just error prone and may result in bug difficult to 
spot, unless you are very aware of all python boolean mechanisms.

JM



From invalid at invalid  Thu Jul 16 10:04:34 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 16 Jul 2009 09:04:34 -0500
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com>
	<mailman.3216.1247751117.8015.python-list@python.org>
Message-ID: <HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>

On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
> On 7/16/2009 2:06 AM Jean-Michel Pichavant said...
>> Ok then, why "or" does not return True, if the first element is 
>> considered True ? Why returning the element itself. Any reason for that 
>> ? Because it's confusing, maybe people used to that logic find it 
>> obvious, but I really don't.
>
> For example, I sometimes use it to set defaults:
>
> daysInAdvance = int(inputVar) or 25

I don't get it.  That doesn't work right when inputVar == "0".

-- 
Grant Edwards                   grante             Yow! What I want to find
                                  at               out is -- do parrots know
                               visi.com            much about Astro-Turf?


From invalid at invalid  Thu Jul 16 10:05:22 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 16 Jul 2009 09:05:22 -0500
Subject: How to search this newsgroup by a python script.
References: <7c897lF26dea4U1@mid.dfncis.de>
	<mailman.3210.1247736812.8015.python-list@python.org>
Message-ID: <HpWdnZdeXqU_rsLXnZ2dnUVZ_qWdnZ2d@posted.visi>

On 2009-07-16, Chris Rebert <clp2 at rebertia.com> wrote:
> On Thu, Jul 16, 2009 at 2:12 AM, Helmut
> Jarausch<jarausch at igpm.rwth-aachen.de> wrote:
>> Hi,
>>
>> I haven't found anything with Google's group search, so let me
>> ask it (again?).
>>
>> How can I search this newsgroup from within a Python script.
>> (Perhaps by searching Google Groups or Gmane by some Python code.)
>
> 1. Generate URL of the form:
> http://search.gmane.org/?query=foo&group=gmane.comp.python.general
> where "foo" is the search terms, with proper URL escaping applied.
> 2. Fetch URL using urllib - http://docs.python.org/library/urllib.html
> 3. Parse resulting HTML page (e.g. using BeautifulSoup)
> 4. Extract desired information from search results using the parse tree.
> 5. ???
> 6. Profit!

The underpants gnomes would be proud.

-- 
Grant Edwards                   grante             Yow! I'm encased in the
                                  at               lining of a pure pork
                               visi.com            sausage!!


From nleioatt at gmail.com  Thu Jul 16 10:07:58 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 16 Jul 2009 07:07:58 -0700 (PDT)
Subject: This is a mess...
Message-ID: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>

I've been coding python for about a week now, and i'm trying to make
an object oriented version of a program i just wrote.  in this post is
the original program.  the next post will include the new programs and
the traceback.  i'm sure there are many underlying problems, but have
been stuck on this for 2 days now...

email me for input files since they are big and i don't see a way to
upload a file here(~5 mB)
this program works, and inputing the same file twice you should get a
"Q" values of ~1 (.99...)

##############CODE#####################

#9July09
#Compute the covariance overlap of two results
#Read in _U.asc files for both ensembles to find e-vectors
#Read in _ .asc files for both ensembles to find sqrt e-values
#strip out matrix info
#compute corvariance


import sys
import math
from math import sqrt


if len(sys.argv) != 3:
    print " "
    print "The corrent usage is 'python covariance.py file1 file2'"
    print "where the _U.asc and _s.asc will be appended when needed"
    print " "
    exit(1)


####Input the first prefix1_U.asc file:
####this is the first eigen vector matrix
prefix1 = sys.argv[1] + "_U.asc"
fileholder = open(prefix1)
text = fileholder.readlines()
fields = text[1].split()
num_rows = int(fields[1])
num_cols = int(fields[2])

U1_matrix = []
for line in text[2: num_rows+2]:
    fields = line.split()
    for i in range(len(fields)):
        fields[i] = float(fields[i])
    U1_matrix.append(fields)

####Input the second prefix2_U.asc file:
####this is the 2nd eigen vector matrix
prefix2 = sys.argv[2] + "_U.asc"
fileholder = open(prefix2)
text = fileholder.readlines()
fields = text[1].split()
num_rows = int(fields[1])
num_cols = int(fields[2])
#print "look here nick:", fields

U2_matrix = []
for line in text[2: num_rows+2]:
    fields = line.split()
    for i in range(len(fields)):
        fields[i] = float(fields[i])
    U2_matrix.append(fields)

####Then Read in the first eigen values
####1st 2 lines are header and need to be stripped away
prefix3 = sys.argv[1] + "_s.asc"
fileholder = open(prefix3)
text = fileholder.readlines()
fields = text[1].split()
num_vals1 = int(fields[1]) #add check to see if correct # of values
added
print "square if", len(U1_matrix), "=", len(U2_matrix), "=", len
(U1_matrix[1]), "=", len(U2_matrix[1])
#the list of sqrt e vals
sqrt_s1 = [float(line) for line in text[2: num_vals1+2]]
s1 = [float(line) * float(line) for line in text[2: num_vals1+2]]

####Finally, read in the 2nd set of eigen vals
prefix4 = sys.argv[2] + "_s.asc"
fileholder = open(prefix4)
text = fileholder.readlines()
fields = text[1].split()
num_vals2 = int(fields[1]) #add check to see if correct # of values
added
#the list of sqrt e vals
sqrt_s2 = [float(line) for line in text[2: num_vals1+2]]
s2 = [float(line) * float(line) for line in text[2: num_vals1+2]]


#=============================================================
####double summation (the 2nd term)
doublesum = 0.0
for i in range(len(U1_matrix[1])):
   #print "i = ", i
    v1 = U1_matrix[i]
    sum = 0
    for j in range(len(U2_matrix)):
         v2 = U2_matrix[j]
         dot = 0
         for k in range(len(U1_matrix)):
             dot += v1[k] * v2[k]
         root = sqrt_s1[i] * sqrt_s2[j]
         sum += root * dot * dot
    doublesum += sum


print "double sum: ", doublesum

####single summation (the 1st term and denominator)
singsum = 0.0
for k in range(len(s1)):
    singsum += s1[k] + s2[k]
print "sing sum:", singsum


####Put it all together
Q = 1 - sqrt(abs((singsum - (2.0*doublesum)) / singsum))
print "your Q:"
print Q

############################# end of code covariance.py



From seldan24 at gmail.com  Thu Jul 16 10:12:24 2009
From: seldan24 at gmail.com (seldan24)
Date: Thu, 16 Jul 2009 07:12:24 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
	<mailman.3175.1247679960.8015.python-list@python.org>
Message-ID: <27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>

On Jul 15, 1:48?pm, Emile van Sebille <em... at fenx.com> wrote:
> On 7/15/2009 10:23 AM MRAB said...
>
> >> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> >>> seldan24 wrote:
> >>>> what can I use as the equivalent for the Unix 'fold' command?
> >>> def fold(s,len):
> >>> ? ? ?while s:
> >>> ? ? ? ? ?print s[:len]
> >>> ? ? ? ? ?s=s[len:]
>
> <snip>
> > You might still need to tweak the above code as regards how line endings
> > are handled.
>
> You might also want to tweak it if the strings are _really_ long to
> simply slice out the substrings as opposed to reassigning the balance to
> a newly created s on each iteration.
>
> Emile

Thanks for all of the help.  I'm almost there.  I have it working now,
but the 'fold' piece is very slow.  When I use the 'fold' command in
shell it is almost instantaneous.  I was able to do the EBCDIC->ASCII
conversion usng the decode method in the built-in str type.  I didn't
have to import the codecs module.  I just decoded the data to cp037
which works fine.

So now, I'm left with a large file, consisting of one extremely long
line of ASCII data that needs to be sliced up into 35 character
lines.  I did the following, which works but takes a very long time:

f = open(ascii_file, 'w')
while ascii_data:
    f.write(ascii_data[:len])
    ascii_data = ascii_data[len:]
f.close()

I know that Emile suggested that I can slice out the substrings rather
than do the gradual trimming of the string variable as is being done
by moving around the length.  So, I'm going to give that a try... I'm
a bit confused by what that means, am guessing that slice can break up
a string based on characters; will research.  Thanks for the help thus
far.  I'll post again when all is working fine.


From aahz at pythoncraft.com  Thu Jul 16 10:14:40 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 07:14:40 -0700
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
Message-ID: <h3nckg$db3$1@panix3.panix.com>

In article <45228cf4-0b37-4c52-bf6f-d7bd124b0f82 at l32g2000vbp.googlegroups.com>,
Tony  Lay  <tonylay at gmail.com> wrote:
>
>Traceback (most recent call last):
>  File "/usr/local/bin/meld", line 35, in <module>
>    import gettext
>  File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
>    import locale, copy, os, re, struct, sys
>  File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
>    import functools
>  File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
>    from _functools import partial, reduce
>ImportError: No module named _functools

Where is _functools.so?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From nleioatt at gmail.com  Thu Jul 16 10:15:52 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 16 Jul 2009 07:15:52 -0700 (PDT)
Subject: This is a mess...
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
Message-ID: <e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>

this is the new oop version, its pretty messy currently, and i do
understand it is a simple routine, but i'm using it as an exercise to
learn oop python...

first the (current) traceback:
 [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
<Eigen.Eigen_vect instance at 0x7fa26c404ab8>
<Eigen.Eigen_vect instance at 0x7fa26c404ab8>
Traceback (most recent call last):
  File "oop_covariance.py", line 24, in <module>
    cov = set1.covariance(set2, Eigen_vect.dot)
  File "/home/nleioatts/python/Eigen.py", line 66, in covariance
    print self.vectors[i][i]
AttributeError: Eigen_vect instance has no attribute '__getitem__'

and a quick explaination:  the file structures aare a 2d list of lists
of numbers corresponding to eginvectors and a list of numbers
corresponding to eigenvalues

#########################33##Here is the main body
#!/usr/bin/env python
import sys
import Eigen
from Eigen import *

if len(sys.argv) != 3:
    print " "
    print "The corrent usage is 'python covariance.py file1 file2'"
    print "where the _U.asc and _s.asc will be appended when needed"
    print " "
    exit(1)
file1 =  sys.argv[1]
file2 =  sys.argv[2]
set1 = Eigen_set(file1+"_U.asc", file1+"_s.asc")
set2 = Eigen_set(file2+"_U.asc", file2+"_s.asc")
cov = set1.covariance(set2, Eigen_vect.dot)
print cov


###############and here are the classes:

#!/usr/bin/env python
import sys
import math
from math import sqrt

class Eigen_vect:
    def __init__(self, e_val, e_vect):
        self.e_val  = e_val
        self.e_vect = e_vect
    def length(self):
        return len(self.e_vect)

    def dot(self, other):
        d = 0.0
        if other.length() != self.length():
            raise ValueError, "Eigen Vectors not same Length"
        for k in range(self.length()):
           # print "HI NICK", self.e_vect[k], other.e_vect[k]
            d += float(self.e_vect[k]) * float(other.e_vect[k])
        return d


class Eigen_set:
    def __init__(self,  vec_filename, val_filename):
        self.vec_filename = vec_filename
        self.val_filename = val_filename
        # open two files
        # loop through them, skipping lines that begin with #
        # for each row, extract eigen vector and eigen values
        fileholder = open(self.vec_filename)
        text = fileholder.readlines()
        fields = text[2].split()
#        print "len of fields", len(fields)
        self.vectors = []
        for line in text[2: len(fields)]:
            fields = line.split()
#            print "len of fields", len(fields)
            for i in range(len(fields)):
                fields[i] = float(fields[i])
        e_vect = fields
        fileholder = open(self.val_filename)
        text = fileholder.readlines()
        e_val = [float(line) for line in text[2: self.length()]]
        self.vectors.append(Eigen_vect(e_val, e_vect))
#        print "this is self.vectors"
#        print self.vectors(e_val)

    def length(self):
        return len(self.vectors)

    def covariance(self, other, dot):
        newdot = 0.0
        # do a length check to make sure we're consistent
        if other.length() != self.length():
            raise ValueError, "Eigen Vectors not same Length"
        #double loop over all my vectors and all of other's vectors
        doublesum = 0.0
        for i in range(self.length()):
            sum = 0.0
            v1 = self.vectors[i]
            for j in range(self.length()):
                newdot += v1.dot(self.vectors[j])
               # root = self.e_val[i] * other.e_val[j]
                print self.vectors[i]
                print self.vectors[j]
                print self.vectors[i][i]
#####################<<------------------------This is line 66, I'm
trying to figure out how to call "e_val" from the Eigen_set class

                root = self.vectors[i][i] * other.vectors[i][j]
                sum  += newdot * newdot * root
            doublesum += sum
        #########
        singsum = 0.0
        for k in range(self.length()):
            singsum += self.e_val[k] * self.e_val[k] + other.e_val[k]
* other.e_val[k]
        Q = 1 - sqrt(abs((singsum - (2.0*doublesum)) / singsum))
        print "your Q:"
        print Q



and any additional help is great.  thanks in advance, like the title
says this is really a mess....


From python.list at tim.thechases.com  Thu Jul 16 10:18:47 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 16 Jul 2009 09:18:47 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
Message-ID: <4A5F36C7.5010307@tim.thechases.com>

> I realize that a small portion of the community likes the tabs.
> They're sold on the tabs. They like the tabs. But tabs are an archaic
> holdover from an era when typewriters had physical tabstops on them.

However, they are a single logical level of indentation -- I come 
down fairly solidly on the "tabs" side of the "tabs vs. spaces" 
argument.  I can set my editor (vim in this case) to show tabs as 
as many spaces as I want.  I usually have this set to 4, but 
sometimes 1 or 2.  In Vim, using tabs I can just switch up my 
tab-stop setting (":set ts=2") and the presentation of my code 
reindents the way I expect.  If I wanted to switch from 
4-real-spaces to 2-real-spaces, I'd have to concoct a perlish 
regexp to handle the munging.

The same "separation of content and presentation" that is all the 
rage with N-tier programmers and web developers, my content is 
"logical levels of indentation indicated by a tab character in 
the source-code" and my presentation is "N spaces as presented by 
my editor".

Yes, the dictatorial "a tab always equals 8 spaces" is a 
vestigial holdover for which I hold no love.

I'll code on other people's projects with spaces if that's the 
project convention (as Vim lets me switch around fairly easily). 
  But as for my own code, it's tabs all the way.

-tkc





From sjmachin at lexicon.net  Thu Jul 16 10:20:25 2009
From: sjmachin at lexicon.net (John Machin)
Date: Thu, 16 Jul 2009 07:20:25 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com> 
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>
Message-ID: <e4bff690-895e-438f-a8eb-3b5c0f0857bc@t11g2000prh.googlegroups.com>

On Jul 16, 11:13?pm, hartley <hartle... at gmail.com> wrote:
> /* the first telling */
> (...)
> /* the second telling */
> (...)
> /* the third telling */
>
> -
> If you had loosened up on the sarcasm

That wasn't sarcasm, it was an attempt at humourous watering-down the
expression of exasperation at continued ignoring of advice and wonder
that I was continuing to bother ...

> HTH,

It didn't.


From aahz at pythoncraft.com  Thu Jul 16 10:22:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 07:22:16 -0700
Subject: Memory leak involving traceback objects
References: <e6e9b9ea-1f8c-4695-90da-72e85c8a63e4@v20g2000yqm.googlegroups.com>
Message-ID: <h3nd2o$ipb$1@panix3.panix.com>

In article <e6e9b9ea-1f8c-4695-90da-72e85c8a63e4 at v20g2000yqm.googlegroups.com>,
Rotem  <vmalloc at gmail.com> wrote:
>
>I'm debugging a nasty memory leak in a framework written in Python
>(v2.6.2).
>After much digging around I found that the entire object group that is
>leaking is held by a frame object which is subsequently held by a
>traceback object.
>
>Traversing the get_referrers() of each traceback frame leads
>eventually to a root traceback frame which has no referrers
>(gc.get_referrers returns an empty list).
>
>However, this traceback object seems not to be picked by the garbage
>collector, and is still there even after many iterations and calls to
>gc.collect(). The code location to which the traceback frame points
>doesn't do anything special - it just catches an exception, without
>saving the exception itself and/or traceback anywhere.

What *does* it do?  Does it re-raise?  This sounds like you're still in
block scope of an exception.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From ifl2009 at shu.edu  Thu Jul 16 10:28:44 2009
From: ifl2009 at shu.edu (IFL 2009)
Date: Thu, 16 Jul 2009 10:28:44 -0400
Subject: IFL 2009: Third Call for Papers
Message-ID: <OF46D7ACB1.F2493CBB-ON852575F5.004F88EE-852575F5.004F88F0@shu.edu>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/4416808b/attachment.html>

From james at agentultra.com  Thu Jul 16 10:49:54 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 16 Jul 2009 10:49:54 -0400
Subject: interactive fiction in Python?
References: <5c97224b-99d4-469b-90cb-1c04b1e1e9a0@m11g2000yqh.googlegroups.com>
Message-ID: <853a8wlm25.fsf@agentultra.com>

George Oliver <georgeoliverGO at gmail.com> writes:

> hi, I'm just curious who might be working on interactive fiction
> modules in the style of Inform or TADS for Python. I've seen a few
> threads on this list [1] (among many that mention IF tangentially),
> and there are old projects like PUB and PAWS. There are some newer
> potential projects such as Curveship as well. In any case I'd like to
> see what's out there.

I'd be interested in checking out such a project, but I don't really see
the point in starting one.  There are already several great IF tools out
there that are already freely available!  The only reason I would see to
start one is either for pure intellectual curiosity or because you have
some feature ideas that no one else has implemented (and you'd rather
cash in on the potential glory than submit a patch!).

Best of luck finding what you're looking for... but maybe you should
start writing one yourself and post here about it! :)

Cheers

>
>
> thanks, George
>
>
> [1]:
>
> http://bit.ly/Python_Text_Adventure_Authoring_System
>
> http://bit.ly/simple_interactive_fiction_engine
>
> http://bit.ly/adventure_engines_in_Python


From james at agentultra.com  Thu Jul 16 10:51:47 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 16 Jul 2009 10:51:47 -0400
Subject: Ann: Google releases Python-based open-source NX server
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
Message-ID: <85y6qok7ek.fsf@agentultra.com>

jkn <jkn_gg at nicorp.f9.co.uk> writes:

> Google quietly releases open-source NX server ...written in Python,
> apparently
>
> <http://www.computerworld.com/s/article/9135504/
> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>
> Neatx can be downloaded from Google's code repository:
>
> <http://code.google.com/p/neatx/>
>
>     Regards
>     J^n

It's pretty cool, but not PEP8! Probably because they just bought the
source off of another smaller proprietary project.  Makes me sad seeing
Google, proud supporter of all things Python, release non-PEP8 code.

Either way, I did check out the project and it looks pretty exciting.
Hopefully I'll get some time to contribute a few patches.


From gabriel.rossetti at arimaz.com  Thu Jul 16 11:12:23 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Thu, 16 Jul 2009 17:12:23 +0200
Subject: no return value for threading.Condition.wait(timeout)?
Message-ID: <4A5F4357.5060402@arimaz.com>

Hello everyone,

I am using threading.Condition.wait(timeout) and was surprised to see 
that there is no return value nor an exception when wait() is used w/ a 
timeout. How am I supposed to know if it was notified or if it timed out?

cheers,
Gabriel


From maxerickson at gmail.com  Thu Jul 16 11:31:36 2009
From: maxerickson at gmail.com (Max Erickson)
Date: Thu, 16 Jul 2009 15:31:36 +0000 (UTC)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<24514309.post@talk.nabble.com> <24514367.post@talk.nabble.com>
Message-ID: <Xns9C4A753E9B41maxericksongmailcom@80.91.229.13>

akhil1988 <akhilanger at gmail.com> wrote:

> 
> akhil1988 wrote:
>> 
>> I have switched to python 3.1 , but now I am getting some syntax
>> errors in the code:
>> 
>> File "./customWikiExtractor.py", line 81
>>     __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;'
>>     :u'\u00A1', 
>> '&cent;'    :u'\u00A2',
>>                                             ^

You may want to try 2.6. Python 3.1 is not syntax compatible with 2.5 
(so the u'' stuff won't work in 3.1):

http://docs.python.org/dev/py3k/whatsnew/3.0.html#removed-syntax



max



From motoom at xs4all.nl  Thu Jul 16 11:34:25 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Thu, 16 Jul 2009 17:34:25 +0200
Subject: Python Equivalent for dd & fold
In-Reply-To: <27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>	<4A5E1082.8090901@mrabarnett.plus.com>	<mailman.3175.1247679960.8015.python-list@python.org>
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <4A5F4881.9090501@xs4all.nl>

seldan24 wrote:

> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length. 

An excellent idea.

def fold(s,chunklength):
     offset=0
     while offset<len(s):
         print s[offset:offset+chunklength]
         offset+=chunklength

s="A very long string indeed. Really that long? Indeed."
fold(s,10)


-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From sjmachin at lexicon.net  Thu Jul 16 11:43:41 2009
From: sjmachin at lexicon.net (John Machin)
Date: Thu, 16 Jul 2009 08:43:41 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com> 
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net> 
	<24514309.post@talk.nabble.com>
	<mailman.3214.1247742266.8015.python-list@python.org>
Message-ID: <dfb3a911-152c-4895-a266-c498d4e8e632@u16g2000pru.googlegroups.com>

On Jul 16, 9:04?pm, akhil1988 <akhilan... at gmail.com> wrote:
> Please click reply on the post and then read this reply in the editor.
> Actually, some sequences have been replaced to their graphical form when
> this post is published. So the python code is being displayed, what actually
> it is not.

What editor? I guess you mean that somebody's browser may be
interpreting the & blah ; thingies .... but this is not relevant; your
syntax error problem is that 2.x unicode literals have a u in front
but 3.x str literals don't IOW you need to lose the first u in
u'\u00A0'


From Caseyweb at gmail.com  Thu Jul 16 11:44:18 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Thu, 16 Jul 2009 08:44:18 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
	<mailman.3175.1247679960.8015.python-list@python.org> 
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <26e55904-58b6-482f-a2b6-c6edfb5bf32e@y4g2000prf.googlegroups.com>

On Jul 16, 10:12?am, seldan24 <selda... at gmail.com> wrote:
> On Jul 15, 1:48?pm, Emile van Sebille <em... at fenx.com> wrote:
>
>
>
> > On 7/15/2009 10:23 AM MRAB said...
>
> > >> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> > >>> seldan24 wrote:
> > >>>> what can I use as the equivalent for the Unix 'fold' command?
> > >>> def fold(s,len):
> > >>> ? ? ?while s:
> > >>> ? ? ? ? ?print s[:len]
> > >>> ? ? ? ? ?s=s[len:]
>
> > <snip>
> > > You might still need to tweak the above code as regards how line endings
> > > are handled.
>
> > You might also want to tweak it if the strings are _really_ long to
> > simply slice out the substrings as opposed to reassigning the balance to
> > a newly created s on each iteration.
>
> > Emile
>
> Thanks for all of the help. ?I'm almost there. ?I have it working now,
> but the 'fold' piece is very slow. ?When I use the 'fold' command in
> shell it is almost instantaneous. ?I was able to do the EBCDIC->ASCII
> conversion usng the decode method in the built-in str type. ?I didn't
> have to import the codecs module. ?I just decoded the data to cp037
> which works fine.
>
> So now, I'm left with a large file, consisting of one extremely long
> line of ASCII data that needs to be sliced up into 35 character
> lines. ?I did the following, which works but takes a very long time:
>
> f = open(ascii_file, 'w')
> while ascii_data:
> ? ? f.write(ascii_data[:len])
> ? ? ascii_data = ascii_data[len:]
> f.close()
>
> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length. ?So, I'm going to give that a try... I'm
> a bit confused by what that means, am guessing that slice can break up
> a string based on characters; will research. ?Thanks for the help thus
> far. ?I'll post again when all is working fine.

The problem is that it creates a new string every time you iterate
through the "ascii_data = ascii_data[len:]".  I believe Emile was
suggesting that you just keep moving the starting index through the
same string, something like (warning - untested code!):

>>> i = 0
>>> str_len = len(ascii_data)
>>> while i < str_len:
>>>     j = min(i + length, str_len)
>>>     print ascii_data[i:j]
>>>     i = j


From pdpinheiro at gmail.com  Thu Jul 16 12:02:25 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Thu, 16 Jul 2009 09:02:25 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
	<mailman.3175.1247679960.8015.python-list@python.org> 
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <4592d512-592b-4e58-829e-e643be34bcec@r33g2000yqn.googlegroups.com>

On Jul 16, 3:12?pm, seldan24 <selda... at gmail.com> wrote:
> On Jul 15, 1:48?pm, Emile van Sebille <em... at fenx.com> wrote:
>
>
>
>
>
> > On 7/15/2009 10:23 AM MRAB said...
>
> > >> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> > >>> seldan24 wrote:
> > >>>> what can I use as the equivalent for the Unix 'fold' command?
> > >>> def fold(s,len):
> > >>> ? ? ?while s:
> > >>> ? ? ? ? ?print s[:len]
> > >>> ? ? ? ? ?s=s[len:]
>
> > <snip>
> > > You might still need to tweak the above code as regards how line endings
> > > are handled.
>
> > You might also want to tweak it if the strings are _really_ long to
> > simply slice out the substrings as opposed to reassigning the balance to
> > a newly created s on each iteration.
>
> > Emile
>
> Thanks for all of the help. ?I'm almost there. ?I have it working now,
> but the 'fold' piece is very slow. ?When I use the 'fold' command in
> shell it is almost instantaneous. ?I was able to do the EBCDIC->ASCII
> conversion usng the decode method in the built-in str type. ?I didn't
> have to import the codecs module. ?I just decoded the data to cp037
> which works fine.
>
> So now, I'm left with a large file, consisting of one extremely long
> line of ASCII data that needs to be sliced up into 35 character
> lines. ?I did the following, which works but takes a very long time:
>
> f = open(ascii_file, 'w')
> while ascii_data:
> ? ? f.write(ascii_data[:len])
> ? ? ascii_data = ascii_data[len:]
> f.close()
>
> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length. ?So, I'm going to give that a try... I'm
> a bit confused by what that means, am guessing that slice can break up
> a string based on characters; will research. ?Thanks for the help thus
> far. ?I'll post again when all is working fine.

Assuming your rather large text file is 1 meg long, you have 1 million
characters in there. 1000000/35 = ~29k lines. The size remaining
string decreases linearly, so the average size is (1000000 + 0) / 2 or
500k. All said and done, you're allocating and copying a 500K string
-- not once, but 29 thousand times. That's where your slowdown resides.


From tn.pablo at gmail.com  Thu Jul 16 12:02:57 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 16 Jul 2009 11:02:57 -0500
Subject: How to check if any item from a list of strings is in a big 
	string?
In-Reply-To: <pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>
Message-ID: <fdd00b510907160902o1707d07dv4eec1a3e1144c6f1@mail.gmail.com>

On Thu, Jul 9, 2009 at 22:07, Steven
D'Aprano<steven at remove.this.cybersource.com.au> wrote:
> On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:
>
>> def list_items_in_string(list_items, string):
>> ? ? for item in list_items:
>> ? ? ? ? if item in string:
>> ? ? ? ? ? ? return True
>> ? ? return False
> ...
>> Any ideas how to make that function look nicer? :)
>
> Change the names. Reverse the order of the arguments. Add a docstring.
>

Why reverse the order of the arguments? Is there a design principle there?

I always make a mess out of the order of my arguments...

-- 
Pablo Torres N.


From degibb at gmail.com  Thu Jul 16 12:15:46 2009
From: degibb at gmail.com (David Gibb)
Date: Thu, 16 Jul 2009 12:15:46 -0400
Subject: list of all possible values
In-Reply-To: <8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>
References: <mailman.3054.1247502101.8015.python-list@python.org>
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
	<8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>
Message-ID: <ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com>

> Certainly possible with list comprehensions.
>
>>>> a = "abc"
>>>> [(x, y) for x in a for y in a]
> [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b', 'c'),
> ('c', 'a'), ('c', 'b'), ('c', 'c')]
>
> But I like bearophile's version better.
>

Andreas,

Thanks, but I think you were missing my point. I should have explained better.

The advantage that bearophile's version is generic with respect to the
number of elements in each combination. To go from 2 element pairs
(e.g. ('a', 'c')) to 5 element pairs (e.g. ('a', 'c', 'b', 'b', 'e'))
requires only a change in a parameter passed to itertools.

I don't see how you would do that with list comprehensions. You're
example works nicely with 2 element pairs, but it seems to me like
you'd need to recode it if you wanted to change it to 5 element pairs.

Am I wrong about that? Can you think of a way to write a function
that, using list comprehensions, takes a list of values and the size
of each combination, and returns the len(list)**(combination size)
possible combinations using those values?

Thanks again,
David


From rylesny at gmail.com  Thu Jul 16 12:23:25 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 16 Jul 2009 09:23:25 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
Message-ID: <a3835950-195f-4857-9688-4768fe1fe1f7@l28g2000vba.googlegroups.com>

On Jul 15, 1:14?pm, seldan24 <selda... at gmail.com> wrote:
> On Jul 15, 12:47?pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>
>
>
> > seldan24 wrote:
> > > what can I use as the equivalent for the Unix 'fold' command?
>
> > def fold(s,len):
> > ? ? ?while s:
> > ? ? ? ? ?print s[:len]
> > ? ? ? ? ?s=s[len:]
>
> > s="A very long string indeed. Really that long? Indeed."
> > fold(s,10)
>
> > Output:
>
> > A very lon
> > g string i
> > ndeed. Rea
> > lly that l
> > ong? Indee
> > d.
>
> > Greetings,
>
> > --
> > "The ability of the OSS process to collect and harness
> > the collective IQ of thousands of individuals across
> > the Internet is simply amazing." - Vinod Valloppillilhttp://www.catb.org/~esr/halloween/halloween4.html
>
> Wow, I feel like a dork. ?I should have done more research prior to
> posting. ?Anyway, thanks for the advice. ?The trouble with Python is
> that things make 'too much' sense. ?Loving this language.

You might also find the textwrap module useful:

http://docs.python.org/library/textwrap.html


From emile at fenx.com  Thu Jul 16 12:23:43 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 09:23:43 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<mailman.3216.1247751117.8015.python-list@python.org>
	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
Message-ID: <h3nk10$tvu$1@ger.gmane.org>

On 7/16/2009 7:04 AM Unknown said...
> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
>> daysInAdvance = int(inputVar) or 25
> 
> I don't get it.  That doesn't work right when inputVar == "0".
> 
Aah, but you didn't get to define right.  :)  For that particular 
example 0 is not a valid response.

Emile



From jeanmichel at sequans.com  Thu Jul 16 12:37:45 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 16 Jul 2009 18:37:45 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3nk10$tvu$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<mailman.3216.1247751117.8015.python-list@python.org>	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
	<h3nk10$tvu$1@ger.gmane.org>
Message-ID: <4A5F5759.4010600@sequans.com>

Emile van Sebille wrote:
> On 7/16/2009 7:04 AM Unknown said...
>> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
>>> daysInAdvance = int(inputVar) or 25
>>
>> I don't get it.  That doesn't work right when inputVar == "0".
>>
> Aah, but you didn't get to define right.  :)  For that particular 
> example 0 is not a valid response.
>
> Emile
>
When I was talking about such error prone form of boolean operations, I 
didn't expect to be right so quickly :p
Steven explained the truth notion with the Something/Nothing. "0" is 
Something, 0 would be Nothing. I'm not sure it makes sens anyway. I 
mean, I could easily argue that the number 0 is something. In the end I 
wonder if I shouldn't just acknowledge the python mechanism without 
trying to find any intuitive/natural/obvious logic in it, knowing that 
sometimes the Truth lies far away from the Evidence.

JM


From andreas.tawn at ubisoft.com  Thu Jul 16 12:49:11 2009
From: andreas.tawn at ubisoft.com (Andreas Tawn)
Date: Thu, 16 Jul 2009 18:49:11 +0200
Subject: list of all possible values
In-Reply-To: <ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com>
References: <mailman.3054.1247502101.8015.python-list@python.org>
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
	<8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>
	<ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com>
Message-ID: <8AEDA5E3386EA742B8C24C95FF0C7580079FCD7C@PDC-MAIL3.ubisoft.org>

> > Certainly possible with list comprehensions.
> >
> >>>> a = "abc"
> >>>> [(x, y) for x in a for y in a]
> > [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
'c'),
> > ('c', 'a'), ('c', 'b'), ('c', 'c')]
> >
> > But I like bearophile's version better.
> >
> 
> Andreas,
> 
> Thanks, but I think you were missing my point. I should have explained
better.
> 
> The advantage that bearophile's version is generic with respect to the
> number of elements in each combination. To go from 2 element pairs
> (e.g. ('a', 'c')) to 5 element pairs (e.g. ('a', 'c', 'b', 'b', 'e'))
> requires only a change in a parameter passed to itertools.
> 
> I don't see how you would do that with list comprehensions. You're
> example works nicely with 2 element pairs, but it seems to me like
> you'd need to recode it if you wanted to change it to 5 element pairs.
> 
> Am I wrong about that? Can you think of a way to write a function
> that, using list comprehensions, takes a list of values and the size
> of each combination, and returns the len(list)**(combination size)
> possible combinations using those values?
> 
> Thanks again,
> David

David,

I think my post got caught in the nebulous email eddys and seems to have
taken 16 hours to arrive on the list. It was meant to be a reply to your
first post, not your second.

Having said that, I think I missed the point of that post too ;o)

Maybe someone smarter than me can come up with a way to dynamically nest
the fors in a list comprehension, but I certainly can't do it.

Sorry for the confusion.

Cheers,

Drea


From python at mrabarnett.plus.com  Thu Jul 16 13:06:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 16 Jul 2009 18:06:09 +0100
Subject: Python Equivalent for dd & fold
In-Reply-To: <27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>	<4A5E1082.8090901@mrabarnett.plus.com>	<mailman.3175.1247679960.8015.python-list@python.org>
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <4A5F5E01.1060505@mrabarnett.plus.com>

seldan24 wrote:
> On Jul 15, 1:48 pm, Emile van Sebille <em... at fenx.com> wrote:
>> On 7/15/2009 10:23 AM MRAB said...
>>
>>>> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>>>>> seldan24 wrote:
>>>>>> what can I use as the equivalent for the Unix 'fold' command?
>>>>> def fold(s,len):
>>>>>      while s:
>>>>>          print s[:len]
>>>>>          s=s[len:]
>> <snip>
>>> You might still need to tweak the above code as regards how line endings
>>> are handled.
>> You might also want to tweak it if the strings are _really_ long to
>> simply slice out the substrings as opposed to reassigning the balance to
>> a newly created s on each iteration.
>>
>> Emile
> 
> Thanks for all of the help.  I'm almost there.  I have it working now,
> but the 'fold' piece is very slow.  When I use the 'fold' command in
> shell it is almost instantaneous.  I was able to do the EBCDIC->ASCII
> conversion usng the decode method in the built-in str type.  I didn't
> have to import the codecs module.  I just decoded the data to cp037
> which works fine.
> 
> So now, I'm left with a large file, consisting of one extremely long
> line of ASCII data that needs to be sliced up into 35 character
> lines.  I did the following, which works but takes a very long time:
> 
> f = open(ascii_file, 'w')
> while ascii_data:
>     f.write(ascii_data[:len])
>     ascii_data = ascii_data[len:]
> f.close()
> 
The 'write' method doesn't append any line ending, so that code gives
the same output as f.write(ascii_data).

> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length.  So, I'm going to give that a try... I'm
> a bit confused by what that means, am guessing that slice can break up
> a string based on characters; will research.  Thanks for the help thus
> far.  I'll post again when all is working fine.



From python at mrabarnett.plus.com  Thu Jul 16 13:07:54 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 16 Jul 2009 18:07:54 +0100
Subject: Python Equivalent for dd & fold
In-Reply-To: <4A5F4881.9090501@xs4all.nl>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>	<4A5E1082.8090901@mrabarnett.plus.com>	<mailman.3175.1247679960.8015.python-list@python.org>	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
	<4A5F4881.9090501@xs4all.nl>
Message-ID: <4A5F5E6A.60104@mrabarnett.plus.com>

Michiel Overtoom wrote:
> seldan24 wrote:
> 
>> I know that Emile suggested that I can slice out the substrings rather
>> than do the gradual trimming of the string variable as is being done
>> by moving around the length. 
> 
> An excellent idea.
> 
> def fold(s,chunklength):
>     offset=0
>     while offset<len(s):
>         print s[offset:offset+chunklength]
>         offset+=chunklength
> 
More Pythonic:

     for offset in range(0, len(s), chunklength):
         print s[offset : offset + chunklength]

> s="A very long string indeed. Really that long? Indeed."
> fold(s,10)
> 



From piet at cs.uu.nl  Thu Jul 16 13:18:04 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 19:18:04 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <m2hbxcv96b.fsf@cs.uu.nl>

>>>>> mheavner <miheavner at gmail.com> (m) wrote:

>m> 'The process' refers to the subprocess. I could do as you say, load
>m> the data structure each time, but the problem is that takes a
>m> considerable amount of time compared to the the actual computation
>m> with the data it contains. I'm using these processes within a loop as
>m> follows:

>m>          # Don't recreate processes or Queues
>m>          pop1 = Queue()
>m>          pop2 = Queue()
>m>          pop_out = Queue()
>m>          p1 = CudaProcess(0, args=(costf,pop1,pop_out))
>m>          p2 = CudaProcess(1, args=(costf,pop2,pop_out))

>m>          # Main loop
>m>          for i in range(maxiter):
>m>                  print 'ITERATION: '+str(i)
>m>                  if log != None:
>m>                          l = open(log,'a')
>m>                  l.write('Iteration: '+str(i)+'\n')
>m>                  l.close()

>m>                  # Split population in two
>m>                  pop1.putmany(pop[0:len(pop)/2])
>m>                  pop2.putmany(pop[len(pop)/2:len(pop)])

>m>                  # Start two processes
>m>                  if not p1.isAlive():
>m>                          p1.start()
>m>                          print 'started %s'%str(p1.getPid())
>m>                  else:
>m>                          p1.run()

That won't work. p1.run() will execute the run method in the Master
process, not in the subprocess. And if it would your could would have a
race condition: between the p1.isAlive() (which must be is_alive btw), and
the p1.run() the process can have stopped.

The proper way to do is to put the work in a Queue and let the processes
get work out of the Queue. The datastructure will remain in the process
then. 

>m>                  if not p2.isAlive():
>m>                          p2.start()
>m>                          print 'started %s'%str(p2.getPid())
>m>                  else:
>m>                          p2.run()
>m>                  .
>m>                  .
>m>                  .

>m> So I'd like to load that data into memory once and keep there as long
>m> as the process is alive (ideally when the subprocess is created,
>m> storing some sort of pointer to it), rather than loading it each time
>m> run is called for a process within the loop. Could be my CudaProcess
>m> class - I'll check out what Diez suggested and post back.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From miheavner at gmail.com  Thu Jul 16 13:37:45 2009
From: miheavner at gmail.com (mheavner)
Date: Thu, 16 Jul 2009 10:37:45 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
	<m2hbxcv96b.fsf@cs.uu.nl>
Message-ID: <2b61ef2d-4bf6-47ba-824d-6b490a342edb@n11g2000yqb.googlegroups.com>

I realize that the Queue would be the best way of doing this, however
that involves transferring the huge amount of data for each call - my
hope was to transfer it once and have it remain in memory for the
subprocess across run() calls.

On Jul 16, 1:18?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> mheavner <miheav... at gmail.com> (m) wrote:
> >m> 'The process' refers to the subprocess. I could do as you say, load
> >m> the data structure each time, but the problem is that takes a
> >m> considerable amount of time compared to the the actual computation
> >m> with the data it contains. I'm using these processes within a loop as
> >m> follows:
> >m> ? ? ? ? ?# Don't recreate processes or Queues
> >m> ? ? ? ? ?pop1 = Queue()
> >m> ? ? ? ? ?pop2 = Queue()
> >m> ? ? ? ? ?pop_out = Queue()
> >m> ? ? ? ? ?p1 = CudaProcess(0, args=(costf,pop1,pop_out))
> >m> ? ? ? ? ?p2 = CudaProcess(1, args=(costf,pop2,pop_out))
> >m> ? ? ? ? ?# Main loop
> >m> ? ? ? ? ?for i in range(maxiter):
> >m> ? ? ? ? ? ? ? ? ?print 'ITERATION: '+str(i)
> >m> ? ? ? ? ? ? ? ? ?if log != None:
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?l = open(log,'a')
> >m> ? ? ? ? ? ? ? ? ?l.write('Iteration: '+str(i)+'\n')
> >m> ? ? ? ? ? ? ? ? ?l.close()
> >m> ? ? ? ? ? ? ? ? ?# Split population in two
> >m> ? ? ? ? ? ? ? ? ?pop1.putmany(pop[0:len(pop)/2])
> >m> ? ? ? ? ? ? ? ? ?pop2.putmany(pop[len(pop)/2:len(pop)])
> >m> ? ? ? ? ? ? ? ? ?# Start two processes
> >m> ? ? ? ? ? ? ? ? ?if not p1.isAlive():
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.start()
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p1.getPid())
> >m> ? ? ? ? ? ? ? ? ?else:
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.run()
>
> That won't work. p1.run() will execute the run method in the Master
> process, not in the subprocess. And if it would your could would have a
> race condition: between the p1.isAlive() (which must be is_alive btw), and
> the p1.run() the process can have stopped.
>
> The proper way to do is to put the work in a Queue and let the processes
> get work out of the Queue. The datastructure will remain in the process
> then.
>
> >m> ? ? ? ? ? ? ? ? ?if not p2.isAlive():
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.start()
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p2.getPid())
> >m> ? ? ? ? ? ? ? ? ?else:
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.run()
> >m> ? ? ? ? ? ? ? ? ?.
> >m> ? ? ? ? ? ? ? ? ?.
> >m> ? ? ? ? ? ? ? ? ?.
> >m> So I'd like to load that data into memory once and keep there as long
> >m> as the process is alive (ideally when the subprocess is created,
> >m> storing some sort of pointer to it), rather than loading it each time
> >m> run is called for a process within the loop. Could be my CudaProcess
> >m> class - I'll check out what Diez suggested and post back.
>
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org



From inky788 at gmail.com  Thu Jul 16 13:47:07 2009
From: inky788 at gmail.com (Inky 788)
Date: Thu, 16 Jul 2009 10:47:07 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
	<mailman.3219.1247753940.8015.python-list@python.org>
Message-ID: <68dbe005-64bc-42f8-99b7-e73c41d0dbd4@r33g2000yqn.googlegroups.com>

On Jul 16, 10:18?am, Tim Chase <python.l... at tim.thechases.com> wrote:
> > I realize that a small portion of the community likes the tabs.
> > They're sold on the tabs. They like the tabs. But tabs are an archaic
> > holdover from an era when typewriters had physical tabstops on them.
>
> However, they are a single logical level of indentation -- I come
> down fairly solidly on the "tabs" side of the "tabs vs. spaces"
> argument.

My bet is that the problem is this: some people like to format their
code in ways that don't work well when you're using tabs. For example,
they might want to call a function like this (note spaces):

some_func(foo=1,
          bar=2,
          baz=3)

instead of:

some_func(
    foo=1,
    bar=2,
    baz=3)

The first one requires 10 spaces in front of bar and baz. If you're
using tabs, that means one or two tabs plus some space characters. So,
people who do that would probably never use tabs. The 2nd example is
fine for tabs or spaces. I'm sure there are a bunch of similar
examples for things besides function calls. Don't you ever find cases
where you'd like to add in an extra space or two to make things line
up nicely?

>?I can set my editor (vim in this case) to show tabs as
> as many spaces as I want. ?I usually have this set to 4, but
> sometimes 1 or 2.

Just curious: why would you want to do that? In my experience, once my
eyes got used to 4-space indents, everything else looks either too
little or too much. :)


From jkn_gg at nicorp.f9.co.uk  Thu Jul 16 13:59:12 2009
From: jkn_gg at nicorp.f9.co.uk (jkn)
Date: Thu, 16 Jul 2009 10:59:12 -0700 (PDT)
Subject: Ann: Google releases Python-based open-source NX server
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
	<85y6qok7ek.fsf@agentultra.com>
Message-ID: <4086976f-11da-4da2-869a-7720510f2bae@m11g2000yqh.googlegroups.com>

On Jul 16, 3:51?pm, J Kenneth King <ja... at agentultra.com> wrote:

> It's pretty cool, but not PEP8! Probably because they just bought the
> source off of another smaller proprietary project. ?Makes me sad seeing
> Google, proud supporter of all things Python, release non-PEP8 code.

Personally, I don't follow PEP8 either. Note: PEP-8 gives 'coding
conventions for the Python code **comprising the standard library in
the main Python distribution**' (my emphasis). My coding conventions
are similar to, but not exactly the same as, PEP-8. It would be
ridiculous IMO (and PEP-8 acknowledges this) for such a permissive
language as Python to put a 'coding style' straitjacket around itself.

YMMV, of course.

    J^n



From emile at fenx.com  Thu Jul 16 14:27:55 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 11:27:55 -0700
Subject: Ann: Google releases Python-based open-source NX server
In-Reply-To: <4086976f-11da-4da2-869a-7720510f2bae@m11g2000yqh.googlegroups.com>
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>	<85y6qok7ek.fsf@agentultra.com>
	<4086976f-11da-4da2-869a-7720510f2bae@m11g2000yqh.googlegroups.com>
Message-ID: <h3nr9t$mig$1@ger.gmane.org>

On 7/16/2009 10:59 AM jkn said...
> Personally, I don't follow PEP8 either. Note: PEP-8 gives 'coding
> conventions for the Python code **comprising the standard library in
> the main Python distribution**' (my emphasis). My coding conventions
> are similar to, but not exactly the same as, PEP-8. 

Mine too, and my objection to PEP-8 is that the coding style doesn't 
allow for copy-n-paste into the interpreter, and I like to be able to 
test that way.  Perhaps if I configured my editor not to strip trailing 
whitespace from lines it would work, but then I don't like trailing 
whitespace.

Of course, I _like_ leading whitespace.  :)

Emile



From robert.kern at gmail.com  Thu Jul 16 14:29:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 16 Jul 2009 13:29:31 -0500
Subject: Ann: Google releases Python-based open-source NX server
In-Reply-To: <85y6qok7ek.fsf@agentultra.com>
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
	<85y6qok7ek.fsf@agentultra.com>
Message-ID: <h3nrib$mq6$1@ger.gmane.org>

On 2009-07-16 09:51, J Kenneth King wrote:
> jkn<jkn_gg at nicorp.f9.co.uk>  writes:
>
>> Google quietly releases open-source NX server ...written in Python,
>> apparently
>>
>> <http://www.computerworld.com/s/article/9135504/
>> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>>
>> Neatx can be downloaded from Google's code repository:
>>
>> <http://code.google.com/p/neatx/>
>>
>>      Regards
>>      J^n
>
> It's pretty cool, but not PEP8! Probably because they just bought the
> source off of another smaller proprietary project.

No, it' just that Google does not use PEP8 for its internal style standard.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python.list at tim.thechases.com  Thu Jul 16 14:40:09 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 16 Jul 2009 13:40:09 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <68dbe005-64bc-42f8-99b7-e73c41d0dbd4@r33g2000yqn.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>	<87ljmwm7ri.fsf@benfinney.id.au>	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>	<mailman.3219.1247753940.8015.python-list@python.org>
	<68dbe005-64bc-42f8-99b7-e73c41d0dbd4@r33g2000yqn.googlegroups.com>
Message-ID: <4A5F7409.8000502@tim.thechases.com>

>> However, they are a single logical level of indentation -- I come
>> down fairly solidly on the "tabs" side of the "tabs vs. spaces"
>> argument.
> 
> My bet is that the problem is this: some people like to format their
> code in ways that don't work well when you're using tabs. For example,
> they might want to call a function like this (note spaces):
> 
> some_func(foo=1,
>           bar=2,
>           baz=3)
> 
> instead of:
> 
> some_func(
>     foo=1,
>     bar=2,
>     baz=3)

For continued indenting statements such as this, I tend to use 
the coding convention used at my first job out of college 
(Computer Sciences Corp...for better or worse) which just indents 
two levels:

   def some_func(foo=1,
   <tab><tab>bar=2,
   <tab><tab>baz=3):
   <tab>do_something(foo)
   <tab>do_other_stuff(bar)

> examples for things besides function calls. Don't you ever find cases
> where you'd like to add in an extra space or two to make things line
> up nicely?

I have occasionally (okay, "very rarely") use the "mixed 
tab+space" method of indentation for continued lines if I want 
them lined up nicely:

   <tab><tab>if (foo == bar and
   <tab><tab>    baz > frob and
   <tab><tab>    fred != barney):
   <tab><tab><tab>do_something()
   <tab><tab><tab>do_more()

This scheme insures that the visual alignment for the 
continued-line matches up, even if the tab-stop is changed.  The 
positioning of the indented block (the do_* bit) floats 
inconveniently with relation to the continued text, with pessimal 
cases being indistinguishable from the continued lines (which is 
why I generally opt not to use this unless it has great benefits 
in code clarity).  By regularly indenting continued lines for 
containing blocks (if, while, etc) by two tabs, the continuation 
stands out from the contained code regardless of my tab stops.

>>  I can set my editor (vim in this case) to show tabs as
>> as many spaces as I want.  I usually have this set to 4, but
>> sometimes 1 or 2.
> 
> Just curious: why would you want to do that? In my experience, once my
> eyes got used to 4-space indents, everything else looks either too
> little or too much. :)

It totally depends on the project -- I like the condensed nature 
of 2sp/tab for code sharing on mailing lists (and tend to copy 
out of vim with tabs expanded to 2 spaces for pasting into 
emails) and for my own visual preference.  If it's code that I'd 
expect anybody else to view, I tend to use 4sp/tab to keep my 
lines below 80 chars per line with the tabs taken into consideration.

I guess I change up my indent enough that sometimes 2 seems just 
right or too small, and sometimes 4 seems just right or too large.

-tkc






From pavlovevidence at gmail.com  Thu Jul 16 14:45:38 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 16 Jul 2009 11:45:38 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
Message-ID: <c7ba5d6e-28a5-4c0f-b764-636476634ae8@t13g2000yqt.googlegroups.com>

On Jul 16, 6:32?am, Inky 788 <inky... at gmail.com> wrote:
> On Jul 10, 7:35?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
>
> > walterbyrd <walterb... at iname.com> writes:
> > > I believe Guido himself has said that all indentions should be four
> > > spaces - no tabs.
>
> > Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
> > with a simple imperative::
>
> > ? ? Use 4 spaces per indentation level.
>
> That actually sounds pretty weird. "Don't do {foo}. Really, I mean
> *really* don't do {foo}. Oh, also, the interpreter allows you to do
> {foo}. But don't do it! I mean it!".
>
> Very ... perlish, if you ask me.

Not Perlish at all.

(Perl would never want you not to use something.)


Carl Banks


From tjreedy at udel.edu  Thu Jul 16 14:50:41 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 14:50:41 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <d3da1b04-0ebb-47a0-88aa-8d214cbf774b@24g2000yqm.googlegroups.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>	<mailman.3202.1247728343.8015.python-list@python.org>	<9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>	<m2zlb5ugnh.fsf@cs.uu.nl>
	<d3da1b04-0ebb-47a0-88aa-8d214cbf774b@24g2000yqm.googlegroups.com>
Message-ID: <h3nsq2$rp4$1@ger.gmane.org>

Mark wrote:
> On 16 July, 10:21, Piet van Oostrum <p... at cs.uu.nl> wrote:

>> But why should the order be as if the OrderedDict was a list of tuples.
>> A dict can be considered as a mapping and then you might want to treat
>> either the key or the value as contravariant (the key I guess). So there
>> is ambiguity. Why would the view as a list of tuples for the ordering be
>> the `natural' view?
>>
>> Maybe you may expect some kind of monotonicity such that d1<d2 implies
>> d1[x]<d2[x], but that doesn't work for d1 = {1:10, 2:20} and d2 = {1:15,
>> 2:5}. So maybe there is only a partial ordering?
> 
> OK, that seems to me to be a convincing argument against supporting
> ordering.

To put the above in a slightly different way. OrderedDicts are a 
recently added niche class that Raymond added to what is mostly his 
collections module because there are enough few use cases. There was 
pydev discussion which included the idea, I believe, that they should 
fundamentally be dicts, not lists. Regardless, the justifying use cases 
did not include a need to compare OrderedDicts. The small fraction of 
the few use cases for OrderedDicts that do require comparision can be 
met by extracting the needed sequences and comparing *them* in the 
appropriate manner. The 'appropriate manner' is not likely to always be 
the same. This point may have come up in the discussion, but I would let 
you check for sure if curious.

'Consistency' is a Python design principle, but it is balanced with 
others, so that it is not sufficient reason to add nearly useless 
features. There is a cost to every addition.

Terry Jan Reedy



From akhilanger at gmail.com  Thu Jul 16 14:57:09 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 11:57:09 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
Message-ID: <24522412.post@talk.nabble.com>


Hi,

Thanks all for the replies.

I am working on a cluster of 15 nodes and I have now installed python 3.1 on
all of them. I tried installing python2.6 but there was some make error. So,
I do not want to give more time in installing 2.4  and rather use 3.1 but
for that I need to convert my 2.4 code to 3.1. 

I used 2to3 tool, and it did make many changes in the 2.4 code, but still
there are some indentation errors that I am unable to resolve being new to
python. I have attached my python code, can anyone please fix the
indentation error in the code. I am using vi editor.

--Thanks a lot,
Akhil http://www.nabble.com/file/p24522412/temp.py temp.py 


alex23 wrote:
> 
> On Jul 16, 9:00?pm, akhil1988 <akhilan... at gmail.com> wrote:
>> I have switched to python 3.1 , but now I am getting some syntax errors
>> in
>> the code:
> 
> Python 3.x was a major release that endeavoured to clean up a number
> of lingering issues with the language, the upshot being that it isn't
> entirely backwards compatible with past versions. Unicode became the
> default string type, which is what is causing the error here: the u-
> prefix is no longer required (or even allowed).
> 
> However, Py3.x _does_ come with a handy tool for automatically
> converting Python 2.x code to 3.x, called 2to3. One of the things it
> should do is convert Py2.x unicode values into their correct
> representation in 3.x.
> 
> With any luck, it should be able to convert the code you're using
> entirely. Let us know how it goes.
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24522412.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From 1x7y2z9 at gmail.com  Thu Jul 16 15:02:52 2009
From: 1x7y2z9 at gmail.com (1x7y2z9)
Date: Thu, 16 Jul 2009 12:02:52 -0700 (PDT)
Subject: URLError errno and strerror not set
Message-ID: <5bbbf0b7-743d-48bc-bd0d-67a6626a58cd@z4g2000prh.googlegroups.com>


python 2.5.2

errno, strerror and message do not appear to be set in the following
two cases (at least).
Is this to be expected?  (as an aside, arg[0] is set)

# case 1
> print exception, exception.errno, exception.strerror, exception.message == ''
<urlopen error (111, 'Connection refused')> None None True

# case 2
> print exception, exception.errno, exception.strerror, exception.message == ''
<urlopen error timed out> None None True

Thanks.


From piet at cs.uu.nl  Thu Jul 16 15:10:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 21:10:08 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
	<m2hbxcv96b.fsf@cs.uu.nl>
	<2b61ef2d-4bf6-47ba-824d-6b490a342edb@n11g2000yqb.googlegroups.com>
Message-ID: <m2d480v3zj.fsf@cs.uu.nl>

>>>>> mheavner <miheavner at gmail.com> (m) wrote:

>m> I realize that the Queue would be the best way of doing this, however
>m> that involves transferring the huge amount of data for each call - my
>m> hope was to transfer it once and have it remain in memory for the
>m> subprocess across run() calls.

Which huge amount of data? The datastructure you talked about can remain
in the process. You only have to transfer the input for your calculation
in the queue but you have to do that anyway. And there is only one run
call per process. When run has terminated the process exits, so you
would have a loop in the run(0 method getting work from the queue.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Thu Jul 16 15:26:02 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 12:26:02 -0700
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com>
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>
Message-ID: <h3nusa$pcb$1@panix3.panix.com>

In article <0afc5c4d-1af5-4d0e-9442-26b51b12e5b4 at m11g2000yqh.googlegroups.com>,
hartley  <hartley79 at gmail.com> wrote:
>
>If you had loosened up on the sarcasm I would probably have read what
>you wrote more thoroughly instead of just skimming through it. Thanks
>for the help, but you should seriously consider doing something with
>your patronizing attitude.

http://www.mikeash.com/getting_answers.html
http://www.catb.org/~esr/faqs/smart-questions.html
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From james at agentultra.com  Thu Jul 16 15:36:11 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 16 Jul 2009 15:36:11 -0400
Subject: Ann: Google releases Python-based open-source NX server
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
	<85y6qok7ek.fsf@agentultra.com>
	<mailman.3232.1247768985.8015.python-list@python.org>
Message-ID: <85r5wgju8k.fsf@agentultra.com>

Robert Kern <robert.kern at gmail.com> writes:

> On 2009-07-16 09:51, J Kenneth King wrote:
>> jkn<jkn_gg at nicorp.f9.co.uk>  writes:
>>
>>> Google quietly releases open-source NX server ...written in Python,
>>> apparently
>>>
>>> <http://www.computerworld.com/s/article/9135504/
>>> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>>>
>>> Neatx can be downloaded from Google's code repository:
>>>
>>> <http://code.google.com/p/neatx/>
>>>
>>>      Regards
>>>      J^n
>>
>> It's pretty cool, but not PEP8! Probably because they just bought the
>> source off of another smaller proprietary project.
>
> No, it' just that Google does not use PEP8 for its internal style standard.

Yeah probably.

I'm just a little OCD sometimes.


From akhilanger at gmail.com  Thu Jul 16 15:41:40 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 12:41:40 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <24522412.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com>
Message-ID: <24523113.post@talk.nabble.com>


ok!
I got the indentation errors fixed. Bu I get another error:

Traceback (most recent call last):
  File "./temp.py", line 484, in <module>
    main()
  File "./temp.py", line 476, in main
    line.decode('utf-8').strip()
AttributeError: 'str' object has no attribute 'decode'

I am using Python3.1

Thanks
Akhil




akhil1988 wrote:
> 
> Hi,
> 
> Thanks all for the replies.
> 
> I am working on a cluster of 15 nodes and I have now installed python 3.1
> on all of them. I tried installing python2.6 but there was some make
> error. So, I do not want to give more time in installing 2.4  and rather
> use 3.1 but for that I need to convert my 2.4 code to 3.1. 
> 
> I used 2to3 tool, and it did make many changes in the 2.4 code, but still
> there are some indentation errors that I am unable to resolve being new to
> python. I have attached my python code, can anyone please fix the
> indentation error in the code. I am using vi editor.
> 
> --Thanks a lot,
> Akhil http://www.nabble.com/file/p24522412/temp.py temp.py 
> 
> 
> alex23 wrote:
>> 
>> On Jul 16, 9:00?pm, akhil1988 <akhilan... at gmail.com> wrote:
>>> I have switched to python 3.1 , but now I am getting some syntax errors
>>> in
>>> the code:
>> 
>> Python 3.x was a major release that endeavoured to clean up a number
>> of lingering issues with the language, the upshot being that it isn't
>> entirely backwards compatible with past versions. Unicode became the
>> default string type, which is what is causing the error here: the u-
>> prefix is no longer required (or even allowed).
>> 
>> However, Py3.x _does_ come with a handy tool for automatically
>> converting Python 2.x code to 3.x, called 2to3. One of the things it
>> should do is convert Py2.x unicode values into their correct
>> representation in 3.x.
>> 
>> With any luck, it should be able to convert the code you're using
>> entirely. Let us know how it goes.
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24523113.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From tonylay at gmail.com  Thu Jul 16 15:45:27 2009
From: tonylay at gmail.com (Tony Lay)
Date: Thu, 16 Jul 2009 12:45:27 -0700 (PDT)
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
	<h3nckg$db3$1@panix3.panix.com>
Message-ID: <df40bd48-7028-4348-8c35-4491c89e2abe@f33g2000vbm.googlegroups.com>

On Jul 16, 10:14?am, a... at pythoncraft.com (Aahz) wrote:
> In article <45228cf4-0b37-4c52-bf6f-d7bd124b0... at l32g2000vbp.googlegroups.com>,
> Tony ?Lay ?<tony... at gmail.com> wrote:
>
>
>
> >Traceback (most recent call last):
> > ?File "/usr/local/bin/meld", line 35, in <module>
> > ? ?import gettext
> > ?File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
> > ? ?import locale, copy, os, re, struct, sys
> > ?File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
> > ? ?import functools
> > ?File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
> > ? ?from _functools import partial, reduce
> >ImportError: No module named _functools
>
> Where is _functools.so?
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "If you think it's expensive to hire a professional to do the job, wait
> until you hire an amateur." ?--Red Adair

/usr/local/lib/python2.6/lib-dynload/

It's in the path...
export PYTHONHOME=/usr/local/lib/python2.6
export PYTHONPATH=/usr/local/lib/python2.6:/usr/local/lib/python2.6/
site-packages:/usr/local/lib/python2.6/lib-dynload:/usr/local/etc/
pango


From tonylay at gmail.com  Thu Jul 16 15:56:31 2009
From: tonylay at gmail.com (Tony Lay)
Date: Thu, 16 Jul 2009 12:56:31 -0700 (PDT)
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
	<h3nckg$db3$1@panix3.panix.com>
Message-ID: <bfd28485-adaf-43ca-963d-3576c1c2cd4e@l2g2000vba.googlegroups.com>

On Jul 16, 10:14?am, a... at pythoncraft.com (Aahz) wrote:
> In article <45228cf4-0b37-4c52-bf6f-d7bd124b0... at l32g2000vbp.googlegroups.com>,
> Tony ?Lay ?<tony... at gmail.com> wrote:
>
>
>
> >Traceback (most recent call last):
> > ?File "/usr/local/bin/meld", line 35, in <module>
> > ? ?import gettext
> > ?File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
> > ? ?import locale, copy, os, re, struct, sys
> > ?File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
> > ? ?import functools
> > ?File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
> > ? ?from _functools import partial, reduce
> >ImportError: No module named _functools
>
> Where is _functools.so?
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "If you think it's expensive to hire a professional to do the job, wait
> until you hire an amateur." ?--Red Adair

/usr/local/lib/python2.6/lib-dynload/

It's in the path...
export PYTHONHOME=/usr/local/lib/python2.6
export PYTHONPATH=/usr/local/lib/python2.6:/usr/local/lib/python2.6/
site-packages:/usr/local/lib/python2.6/lib-dynload:/usr/local/etc/
pango


From kyrie at uh.cu  Thu Jul 16 15:57:02 2009
From: kyrie at uh.cu (Luis Alberto Zarrabeitia Gomez)
Date: Thu, 16 Jul 2009 15:57:02 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5F5759.4010600@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com>
	<mailman.3216.1247751117.8015.python-list@python.org>
	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
	<h3nk10$tvu$1@ger.gmane.org> <4A5F5759.4010600@sequans.com>
Message-ID: <1247774222.4a5f860ec3cfa@mail.uh.cu>


Quoting Jean-Michel Pichavant <jeanmichel at sequans.com>:

> Emile van Sebille wrote:
> > On 7/16/2009 7:04 AM Unknown said...
> >> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
> >>> daysInAdvance = int(inputVar) or 25
> >>
> >> I don't get it.  That doesn't work right when inputVar == "0".
> >>
> > Aah, but you didn't get to define right.  :)  For that particular 
> > example 0 is not a valid response.
>
> When I was talking about such error prone form of boolean operations, I 
> didn't expect to be right so quickly :p

What do you mean by being "right so quickly", and "error prone" in this context?
I would also ask "Unknown" why he believes that "int(intputVar) or 25" doesn't
work right when inputVar == "0". The only false value that int() may return is
zero, so the "or 25" clause is there only for that case. I can't see then how
you think that is an error.

> I'm not sure it makes sens anyway. I 
> mean, I could easily argue that the number 0 is something. In the end I 
> wonder if I shouldn't just acknowledge the python mechanism 

Then look it another way. The "Empty/Nothing" is just standard practice, there
is nothing in python that forces you to be "false" if you are empty, or true
otherwise. Instead, answer this: why do you need a /boolean/ value? Is there any
case where you need to be certain that the object's type is 'bool'? If you think
the answer is "yes", you may want to get more familiar with the "duck typing"
concept. (That doesn't mean that there are no legitimate cases where duck typing
is inappropriate, but that there are many cases where people, specially if they
come from statically typed languages, may believe that it is inappropriate when
it isn't).

In the python world, one should care more about how an object /behaves/ than
from what clase it came. If something quacks like a duck, then assume that it is
a duck, at least for the quacking part.

Most python objects carry a truth value. Sometimes it feels natural (None is
"false", boolean True and False are "true" and "false", empty containers are
expected to be false, 0 and '' are "false"). Sometimes, it is everything but
natural, but that's a problem with the object's implementation (datetime.time
comes to mind). So, you shouldn't care if you have a bool instance - it should
be enough that it behaves like a bool (though, if you need a bool, you can
always construct one). The "True or False" expression could return Giraffes, as
long as Giraffes behave like the bool "True" in boolean context. If you care
about the class of the result, you can ask for its truth value, and if you don't
care about it, you can just ignore it, and use it as you would use a bool.

And then, if you can return any object as long as it behaves properly, what
would be better to return? A new bool? Why not new Giraffe, if they will have
the same behaviour? Guido chose to return the a value that will say more about
the result of the operation than just a boolean. It acts as a boolean - if you
don't need anything else, treat it as such -, but it will be, whenever is
possible, one of the objects in the sequence, in case you need more info.

> without 
> trying to find any intuitive/natural/obvious logic in it, knowing that 
> sometimes the Truth lies far away from the Evidence.

Don't do that. Many of python's decisions are very well thought. You may
disagree with them, as I do with some, but they are rarely taken lightly. And
this is one that I find very agreeable and in line with the rest of python's
philosophy.

-- 
Luis Zarrabeitia
Facultad de Matem?tica y Computaci?n, UH
http://profesores.matcom.uh.cu/~kyrie



-- 
Participe en Universidad 2010, del 8 al 12 de febrero de 2010
La Habana, Cuba 
http://www.universidad2010.cu



From piet at cs.uu.nl  Thu Jul 16 16:01:22 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 22:01:22 +0200
Subject: This is a mess...
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
	<e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
Message-ID: <m263dsv1m5.fsf@cs.uu.nl>

>>>>> Nick <nleioatt at gmail.com> (N) wrote:

>N> this is the new oop version, its pretty messy currently, and i do
>N> understand it is a simple routine, but i'm using it as an exercise to
>N> learn oop python...

>N> first the (current) traceback:
>N>  [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
>N> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
>N> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
>N> Traceback (most recent call last):
>N>   File "oop_covariance.py", line 24, in <module>
>N>     cov = set1.covariance(set2, Eigen_vect.dot)
>N>   File "/home/nleioatts/python/Eigen.py", line 66, in covariance
>N>     print self.vectors[i][i]
>N> AttributeError: Eigen_vect instance has no attribute '__getitem__'

self.vectors is a list of Eigen_vect objects. So self.vectors[i] is an
Eigen_vect object. Now you do a subscript on this Eigen_vect object but
you have not defined what that means. Presumably you want it to do the
subscript on the self.e_vect in the Eigen_vect instance. Therefore you
have to define the __getitem__ method in the Eigen_vect class.


class Eigen_vect:
    def __init__(self, e_val, e_vect):
        self.e_val  = e_val
        self.e_vect = e_vect
    def length(self):
        return len(self.e_vect)

    def __getitem__(self, indx):
        return self.e_vect[indx]

I hope I did not make a mistake, I didn't check it because I don't want
to make test input files.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nobody at nowhere.com  Thu Jul 16 16:17:05 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 21:17:05 +0100
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
	<mailman.3219.1247753940.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.20.15.13.719000@nowhere.com>

On Thu, 16 Jul 2009 09:18:47 -0500, Tim Chase wrote:

> Yes, the dictatorial "a tab always equals 8 spaces"

Saying "always" is incorrect; it is more accurate to say that tab stops
are every 8 columns unless proven otherwise, with the burden of proof
falling on whoever wants to use something different.



From mensanator at aol.com  Thu Jul 16 16:23:38 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 16 Jul 2009 13:23:38 -0700 (PDT)
Subject: list of all possible values
References: <mailman.3054.1247502101.8015.python-list@python.org> 
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com> 
	<8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org> 
	<ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com> 
	<mailman.3227.1247762965.8015.python-list@python.org>
Message-ID: <c6064b08-6f68-4ce4-8eb9-83ad32eea919@k6g2000yqn.googlegroups.com>

On Jul 16, 11:49 am, "Andreas Tawn" <andreas.t... at ubisoft.com> wrote:
> > > Certainly possible with list comprehensions.
>
> > >>>> a = "abc"
> > >>>> [(x, y) for x in a for y in a]
> > > [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
> 'c'),
> > > ('c', 'a'), ('c', 'b'), ('c', 'c')]
>
> > > But I like bearophile's version better.
>
> > Andreas,
>
> > Thanks, but I think you were missing my point. I should have explained
> better.
>
> > The advantage that bearophile's version is generic with respect to the
> > number of elements in each combination. To go from 2 element pairs
> > (e.g. ('a', 'c')) to 5 element pairs (e.g. ('a', 'c', 'b', 'b', 'e'))
> > requires only a change in a parameter passed to itertools.
>
> > I don't see how you would do that with list comprehensions. You're
> > example works nicely with 2 element pairs, but it seems to me like
> > you'd need to recode it if you wanted to change it to 5 element pairs.
>
> > Am I wrong about that? Can you think of a way to write a function
> > that, using list comprehensions, takes a list of values and the size
> > of each combination, and returns the len(list)**(combination size)
> > possible combinations using those values?
>
> > Thanks again,
> > David
>
> David,
>
> I think my post got caught in the nebulous email eddys and seems to have
> taken 16 hours to arrive on the list. It was meant to be a reply to your
> first post, not your second.
>
> Having said that, I think I missed the point of that post too ;o)
>
> Maybe someone smarter than me can come up with a way to dynamically nest
> the fors in a list comprehension, but I certainly can't do it.

Well, I don't use list comprehension, but you can certainly
make dynamic for loops. Not that this is a replacement for
itertools (I wrote it before itertools had the ability to do
all this).

def ooloop6(a, n, perm=True, repl=True):
    if (not repl) and (n>len(a)): return
    r0 = range(n)
    r1 = r0[1:]
    if perm and repl:                          # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        e = ''.join(["p = [''.join((",v,")) ",f,"]"])
        exec e
        return p
    if (not perm) and repl:                    # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        i = ' and '.join(['(c%s>=c%s)' % (j,j-1) for j in r1])
        e = ''.join(["p = [''.join((",v,")) ",f," if ",i,"]"])
        exec e
        return p
    if perm and (not repl):                    # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        i = ' and '.join([' and '.join(['(c%s!=c%s)' % (j,k) for k in
range(j)]) for j in r1])
        e = ''.join(["p = [''.join((",v,")) ",f," if ",i,"]"])
        exec e
        return p
    if (not perm) and (not repl):              # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        i = ' and '.join(['(c%s>c%s)' % (j,j-1) for j in r1])
        e = ''.join(["p = [''.join((",v,")) ",f," if ",i,"]"])
        exec e
        return p

print '0123456789 taken 2 at a time'

p = ooloop6('0123456789',2,True,True)
print
print 'Permutations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',2,True,False)
print
print 'Permutations without Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',2,False,True)
print
print 'Combinations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',2,False,False)
print
print 'Combinations without Replacement: %6d' % (len(p))
print p

print

print '0123456789 taken 3 at a time'

p = ooloop6('0123456789',3,True,True)
print
print 'Permutations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',3,True,False)
print
print 'Permutations without Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',3,False,True)
print
print 'Combinations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',3,False,False)
print
print 'Combinations without Replacement: %6d' % (len(p))
print p

0123456789 taken 2 at a time

Permutations with    Replacement:    100
['00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '10',
'11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21',
'22', '23', '24', '25', '26', '27', '28', '29', '30', '31', '32',
'33', '34', '35', '36', '37', '38', '39', '40', '41', '42', '43',
'44', '45', '46', '47', '48', '49', '50', '51', '52', '53', '54',
'55', '56', '57', '58', '59', '60', '61', '62', '63', '64', '65',
'66', '67', '68', '69', '70', '71', '72', '73', '74', '75', '76',
'77', '78', '79', '80', '81', '82', '83', '84', '85', '86', '87',
'88', '89', '90', '91', '92', '93', '94', '95', '96', '97', '98',
'99']

Permutations without Replacement:     90
['01', '02', '03', '04', '05', '06', '07', '08', '09', '10', '12',
'13', '14', '15', '16', '17', '18', '19', '20', '21', '23', '24',
'25', '26', '27', '28', '29', '30', '31', '32', '34', '35', '36',
'37', '38', '39', '40', '41', '42', '43', '45', '46', '47', '48',
'49', '50', '51', '52', '53', '54', '56', '57', '58', '59', '60',
'61', '62', '63', '64', '65', '67', '68', '69', '70', '71', '72',
'73', '74', '75', '76', '78', '79', '80', '81', '82', '83', '84',
'85', '86', '87', '89', '90', '91', '92', '93', '94', '95', '96',
'97', '98']

Combinations with    Replacement:     55
['00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '11',
'12', '13', '14', '15', '16', '17', '18', '19', '22', '23', '24',
'25', '26', '27', '28', '29', '33', '34', '35', '36', '37', '38',
'39', '44', '45', '46', '47', '48', '49', '55', '56', '57', '58',
'59', '66', '67', '68', '69', '77', '78', '79', '88', '89', '99']

Combinations without Replacement:     45
['01', '02', '03', '04', '05', '06', '07', '08', '09', '12', '13',
'14', '15', '16', '17', '18', '19', '23', '24', '25', '26', '27',
'28', '29', '34', '35', '36', '37', '38', '39', '45', '46', '47',
'48', '49', '56', '57', '58', '59', '67', '68', '69', '78', '79',
'89']

0123456789 taken 3 at a time

Permutations with    Replacement:   1000
['000', '001', '002', '003', '004', '005', '006', '007', '008', '009',
'010', '011', '012', '013', '014', '015', '016', '017', '018', '019',
'020', '021', '022', '023', '024', '025', '026', '027', '028', '029',
'030', '031', '032', '033', '034', '035', '036', '037', '038', '039',
'040', '041', '042', '043', '044', '045', '046', '047', '048', '049',
'050', '051', '052', '053', '054', '055', '056', '057', '058', '059',
'060', '061', '062', '063', '064', '065', '066', '067', '068', '069',
'070', '071', '072', '073', '074', '075', '076', '077', '078', '079',
'080', '081', '082', '083', '084', '085', '086', '087', '088', '089',
'090', '091', '092', '093', '094', '095', '096', '097', '098', '099',
'100', '101', '102', '103', '104', '105', '106', '107', '108', '109',
'110', '111', '112', '113', '114', '115', '116', '117', '118', '119',
'120', '121', '122', '123', '124', '125', '126', '127', '128', '129',
'130', '131', '132', '133', '134', '135', '136', '137', '138', '139',
'140', '141', '142', '143', '144', '145', '146', '147', '148', '149',
'150', '151', '152', '153', '154', '155', '156', '157', '158', '159',
'160', '161', '162', '163', '164', '165', '166', '167', '168', '169',
'170', '171', '172', '173', '174', '175', '176', '177', '178', '179',
'180', '181', '182', '183', '184', '185', '186', '187', '188', '189',
'190', '191', '192', '193', '194', '195', '196', '197', '198', '199',
'200', '201', '202', '203', '204', '205', '206', '207', '208', '209',
'210', '211', '212', '213', '214', '215', '216', '217', '218', '219',
'220', '221', '222', '223', '224', '225', '226', '227', '228', '229',
'230', '231', '232', '233', '234', '235', '236', '237', '238', '239',
'240', '241', '242', '243', '244', '245', '246', '247', '248', '249',
'250', '251', '252', '253', '254', '255', '256', '257', '258', '259',
'260', '261', '262', '263', '264', '265', '266', '267', '268', '269',
'270', '271', '272', '273', '274', '275', '276', '277', '278', '279',
'280', '281', '282', '283', '284', '285', '286', '287', '288', '289',
'290', '291', '292', '293', '294', '295', '296', '297', '298', '299',
'300', '301', '302', '303', '304', '305', '306', '307', '308', '309',
'310', '311', '312', '313', '314', '315', '316', '317', '318', '319',
'320', '321', '322', '323', '324', '325', '326', '327', '328', '329',
'330', '331', '332', '333', '334', '335', '336', '337', '338', '339',
'340', '341', '342', '343', '344', '345', '346', '347', '348', '349',
'350', '351', '352', '353', '354', '355', '356', '357', '358', '359',
'360', '361', '362', '363', '364', '365', '366', '367', '368', '369',
'370', '371', '372', '373', '374', '375', '376', '377', '378', '379',
'380', '381', '382', '383', '384', '385', '386', '387', '388', '389',
'390', '391', '392', '393', '394', '395', '396', '397', '398', '399',
'400', '401', '402', '403', '404', '405', '406', '407', '408', '409',
'410', '411', '412', '413', '414', '415', '416', '417', '418', '419',
'420', '421', '422', '423', '424', '425', '426', '427', '428', '429',
'430', '431', '432', '433', '434', '435', '436', '437', '438', '439',
'440', '441', '442', '443', '444', '445', '446', '447', '448', '449',
'450', '451', '452', '453', '454', '455', '456', '457', '458', '459',
'460', '461', '462', '463', '464', '465', '466', '467', '468', '469',
'470', '471', '472', '473', '474', '475', '476', '477', '478', '479',
'480', '481', '482', '483', '484', '485', '486', '487', '488', '489',
'490', '491', '492', '493', '494', '495', '496', '497', '498', '499',
'500', '501', '502', '503', '504', '505', '506', '507', '508', '509',
'510', '511', '512', '513', '514', '515', '516', '517', '518', '519',
'520', '521', '522', '523', '524', '525', '526', '527', '528', '529',
'530', '531', '532', '533', '534', '535', '536', '537', '538', '539',
'540', '541', '542', '543', '544', '545', '546', '547', '548', '549',
'550', '551', '552', '553', '554', '555', '556', '557', '558', '559',
'560', '561', '562', '563', '564', '565', '566', '567', '568', '569',
'570', '571', '572', '573', '574', '575', '576', '577', '578', '579',
'580', '581', '582', '583', '584', '585', '586', '587', '588', '589',
'590', '591', '592', '593', '594', '595', '596', '597', '598', '599',
'600', '601', '602', '603', '604', '605', '606', '607', '608', '609',
'610', '611', '612', '613', '614', '615', '616', '617', '618', '619',
'620', '621', '622', '623', '624', '625', '626', '627', '628', '629',
'630', '631', '632', '633', '634', '635', '636', '637', '638', '639',
'640', '641', '642', '643', '644', '645', '646', '647', '648', '649',
'650', '651', '652', '653', '654', '655', '656', '657', '658', '659',
'660', '661', '662', '663', '664', '665', '666', '667', '668', '669',
'670', '671', '672', '673', '674', '675', '676', '677', '678', '679',
'680', '681', '682', '683', '684', '685', '686', '687', '688', '689',
'690', '691', '692', '693', '694', '695', '696', '697', '698', '699',
'700', '701', '702', '703', '704', '705', '706', '707', '708', '709',
'710', '711', '712', '713', '714', '715', '716', '717', '718', '719',
'720', '721', '722', '723', '724', '725', '726', '727', '728', '729',
'730', '731', '732', '733', '734', '735', '736', '737', '738', '739',
'740', '741', '742', '743', '744', '745', '746', '747', '748', '749',
'750', '751', '752', '753', '754', '755', '756', '757', '758', '759',
'760', '761', '762', '763', '764', '765', '766', '767', '768', '769',
'770', '771', '772', '773', '774', '775', '776', '777', '778', '779',
'780', '781', '782', '783', '784', '785', '786', '787', '788', '789',
'790', '791', '792', '793', '794', '795', '796', '797', '798', '799',
'800', '801', '802', '803', '804', '805', '806', '807', '808', '809',
'810', '811', '812', '813', '814', '815', '816', '817', '818', '819',
'820', '821', '822', '823', '824', '825', '826', '827', '828', '829',
'830', '831', '832', '833', '834', '835', '836', '837', '838', '839',
'840', '841', '842', '843', '844', '845', '846', '847', '848', '849',
'850', '851', '852', '853', '854', '855', '856', '857', '858', '859',
'860', '861', '862', '863', '864', '865', '866', '867', '868', '869',
'870', '871', '872', '873', '874', '875', '876', '877', '878', '879',
'880', '881', '882', '883', '884', '885', '886', '887', '888', '889',
'890', '891', '892', '893', '894', '895', '896', '897', '898', '899',
'900', '901', '902', '903', '904', '905', '906', '907', '908', '909',
'910', '911', '912', '913', '914', '915', '916', '917', '918', '919',
'920', '921', '922', '923', '924', '925', '926', '927', '928', '929',
'930', '931', '932', '933', '934', '935', '936', '937', '938', '939',
'940', '941', '942', '943', '944', '945', '946', '947', '948', '949',
'950', '951', '952', '953', '954', '955', '956', '957', '958', '959',
'960', '961', '962', '963', '964', '965', '966', '967', '968', '969',
'970', '971', '972', '973', '974', '975', '976', '977', '978', '979',
'980', '981', '982', '983', '984', '985', '986', '987', '988', '989',
'990', '991', '992', '993', '994', '995', '996', '997', '998', '999']

Permutations without Replacement:    720
['012', '013', '014', '015', '016', '017', '018', '019', '021', '023',
'024', '025', '026', '027', '028', '029', '031', '032', '034', '035',
'036', '037', '038', '039', '041', '042', '043', '045', '046', '047',
'048', '049', '051', '052', '053', '054', '056', '057', '058', '059',
'061', '062', '063', '064', '065', '067', '068', '069', '071', '072',
'073', '074', '075', '076', '078', '079', '081', '082', '083', '084',
'085', '086', '087', '089', '091', '092', '093', '094', '095', '096',
'097', '098', '102', '103', '104', '105', '106', '107', '108', '109',
'120', '123', '124', '125', '126', '127', '128', '129', '130', '132',
'134', '135', '136', '137', '138', '139', '140', '142', '143', '145',
'146', '147', '148', '149', '150', '152', '153', '154', '156', '157',
'158', '159', '160', '162', '163', '164', '165', '167', '168', '169',
'170', '172', '173', '174', '175', '176', '178', '179', '180', '182',
'183', '184', '185', '186', '187', '189', '190', '192', '193', '194',
'195', '196', '197', '198', '201', '203', '204', '205', '206', '207',
'208', '209', '210', '213', '214', '215', '216', '217', '218', '219',
'230', '231', '234', '235', '236', '237', '238', '239', '240', '241',
'243', '245', '246', '247', '248', '249', '250', '251', '253', '254',
'256', '257', '258', '259', '260', '261', '263', '264', '265', '267',
'268', '269', '270', '271', '273', '274', '275', '276', '278', '279',
'280', '281', '283', '284', '285', '286', '287', '289', '290', '291',
'293', '294', '295', '296', '297', '298', '301', '302', '304', '305',
'306', '307', '308', '309', '310', '312', '314', '315', '316', '317',
'318', '319', '320', '321', '324', '325', '326', '327', '328', '329',
'340', '341', '342', '345', '346', '347', '348', '349', '350', '351',
'352', '354', '356', '357', '358', '359', '360', '361', '362', '364',
'365', '367', '368', '369', '370', '371', '372', '374', '375', '376',
'378', '379', '380', '381', '382', '384', '385', '386', '387', '389',
'390', '391', '392', '394', '395', '396', '397', '398', '401', '402',
'403', '405', '406', '407', '408', '409', '410', '412', '413', '415',
'416', '417', '418', '419', '420', '421', '423', '425', '426', '427',
'428', '429', '430', '431', '432', '435', '436', '437', '438', '439',
'450', '451', '452', '453', '456', '457', '458', '459', '460', '461',
'462', '463', '465', '467', '468', '469', '470', '471', '472', '473',
'475', '476', '478', '479', '480', '481', '482', '483', '485', '486',
'487', '489', '490', '491', '492', '493', '495', '496', '497', '498',
'501', '502', '503', '504', '506', '507', '508', '509', '510', '512',
'513', '514', '516', '517', '518', '519', '520', '521', '523', '524',
'526', '527', '528', '529', '530', '531', '532', '534', '536', '537',
'538', '539', '540', '541', '542', '543', '546', '547', '548', '549',
'560', '561', '562', '563', '564', '567', '568', '569', '570', '571',
'572', '573', '574', '576', '578', '579', '580', '581', '582', '583',
'584', '586', '587', '589', '590', '591', '592', '593', '594', '596',
'597', '598', '601', '602', '603', '604', '605', '607', '608', '609',
'610', '612', '613', '614', '615', '617', '618', '619', '620', '621',
'623', '624', '625', '627', '628', '629', '630', '631', '632', '634',
'635', '637', '638', '639', '640', '641', '642', '643', '645', '647',
'648', '649', '650', '651', '652', '653', '654', '657', '658', '659',
'670', '671', '672', '673', '674', '675', '678', '679', '680', '681',
'682', '683', '684', '685', '687', '689', '690', '691', '692', '693',
'694', '695', '697', '698', '701', '702', '703', '704', '705', '706',
'708', '709', '710', '712', '713', '714', '715', '716', '718', '719',
'720', '721', '723', '724', '725', '726', '728', '729', '730', '731',
'732', '734', '735', '736', '738', '739', '740', '741', '742', '743',
'745', '746', '748', '749', '750', '751', '752', '753', '754', '756',
'758', '759', '760', '761', '762', '763', '764', '765', '768', '769',
'780', '781', '782', '783', '784', '785', '786', '789', '790', '791',
'792', '793', '794', '795', '796', '798', '801', '802', '803', '804',
'805', '806', '807', '809', '810', '812', '813', '814', '815', '816',
'817', '819', '820', '821', '823', '824', '825', '826', '827', '829',
'830', '831', '832', '834', '835', '836', '837', '839', '840', '841',
'842', '843', '845', '846', '847', '849', '850', '851', '852', '853',
'854', '856', '857', '859', '860', '861', '862', '863', '864', '865',
'867', '869', '870', '871', '872', '873', '874', '875', '876', '879',
'890', '891', '892', '893', '894', '895', '896', '897', '901', '902',
'903', '904', '905', '906', '907', '908', '910', '912', '913', '914',
'915', '916', '917', '918', '920', '921', '923', '924', '925', '926',
'927', '928', '930', '931', '932', '934', '935', '936', '937', '938',
'940', '941', '942', '943', '945', '946', '947', '948', '950', '951',
'952', '953', '954', '956', '957', '958', '960', '961', '962', '963',
'964', '965', '967', '968', '970', '971', '972', '973', '974', '975',
'976', '978', '980', '981', '982', '983', '984', '985', '986', '987']

Combinations with    Replacement:    220
['000', '001', '002', '003', '004', '005', '006', '007', '008', '009',
'011', '012', '013', '014', '015', '016', '017', '018', '019', '022',
'023', '024', '025', '026', '027', '028', '029', '033', '034', '035',
'036', '037', '038', '039', '044', '045', '046', '047', '048', '049',
'055', '056', '057', '058', '059', '066', '067', '068', '069', '077',
'078', '079', '088', '089', '099', '111', '112', '113', '114', '115',
'116', '117', '118', '119', '122', '123', '124', '125', '126', '127',
'128', '129', '133', '134', '135', '136', '137', '138', '139', '144',
'145', '146', '147', '148', '149', '155', '156', '157', '158', '159',
'166', '167', '168', '169', '177', '178', '179', '188', '189', '199',
'222', '223', '224', '225', '226', '227', '228', '229', '233', '234',
'235', '236', '237', '238', '239', '244', '245', '246', '247', '248',
'249', '255', '256', '257', '258', '259', '266', '267', '268', '269',
'277', '278', '279', '288', '289', '299', '333', '334', '335', '336',
'337', '338', '339', '344', '345', '346', '347', '348', '349', '355',
'356', '357', '358', '359', '366', '367', '368', '369', '377', '378',
'379', '388', '389', '399', '444', '445', '446', '447', '448', '449',
'455', '456', '457', '458', '459', '466', '467', '468', '469', '477',
'478', '479', '488', '489', '499', '555', '556', '557', '558', '559',
'566', '567', '568', '569', '577', '578', '579', '588', '589', '599',
'666', '667', '668', '669', '677', '678', '679', '688', '689', '699',
'777', '778', '779', '788', '789', '799', '888', '889', '899', '999']

Combinations without Replacement:    120
['012', '013', '014', '015', '016', '017', '018', '019', '023', '024',
'025', '026', '027', '028', '029', '034', '035', '036', '037', '038',
'039', '045', '046', '047', '048', '049', '056', '057', '058', '059',
'067', '068', '069', '078', '079', '089', '123', '124', '125', '126',
'127', '128', '129', '134', '135', '136', '137', '138', '139', '145',
'146', '147', '148', '149', '156', '157', '158', '159', '167', '168',
'169', '178', '179', '189', '234', '235', '236', '237', '238', '239',
'245', '246', '247', '248', '249', '256', '257', '258', '259', '267',
'268', '269', '278', '279', '289', '345', '346', '347', '348', '349',
'356', '357', '358', '359', '367', '368', '369', '378', '379', '389',
'456', '457', '458', '459', '467', '468', '469', '478', '479', '489',
'567', '568', '569', '578', '579', '589', '678', '679', '689', '789']
>>>

>
> Sorry for the confusion.
>
> Cheers,
>
> Drea


From nobody at nowhere.com  Thu Jul 16 16:25:50 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 21:25:50 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<mailman.3209.1247735227.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.20.23.58.953000@nowhere.com>

On Thu, 16 Jul 2009 11:06:54 +0200, Jean-Michel Pichavant wrote:

>>> So if I resume:
>>> - not 'foo' => False
>>> - 'foo' or 'foo' => 'foo'
>>>
>>> I may be missing something, but honestly, Guido must have smoked some 
>>> heavy stuff to write such logic, has he ?
>>
>> Several languages (e.g. Lisp, Bourne shell) behave the same way, i.e. "or"
>> returns the first element which is considered true while "and" returns the
>> last element provided that all preceding elements are considered true.
>>   
>> [snip]
>>   
> 
> Ok then, why "or" does not return True, if the first element is 
> considered True ?

If the first element is true, returning the first element is returning
true.

> Why returning the element itself. Any reason for that ?

Why not? Where is the benefit in collapsing all true values to True? You
can convert values to True/False with bool(), but the conversion cannot be
reversed.

It only makes a difference if you are interested in the representation
rather than the value. Do you normally test for equality with "is" or "=="?



From nobody at nowhere.com  Thu Jul 16 16:29:07 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 21:29:07 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <pan.2009.07.16.20.27.15.563000@nowhere.com>

On Wed, 15 Jul 2009 18:14:10 +0200, Hrvoje Niksic wrote:

>> If the question was "Why is there no 'or' operator ?", would "because
>> A or B <=> not(not A and not B)" be a proper answer ?
> 
> Note that in Python A or B is in fact not equivalent to not(not A and
> not B).

Ah, but it *is* "equivalent"; it isn't "identical", but that's not the
point.



From nick at craig-wood.com  Thu Jul 16 16:29:59 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 16 Jul 2009 15:29:59 -0500
Subject: This is a mess...
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
	<e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
Message-ID: <slrnh5v2fn.b32.nick@irishsea.home.craig-wood.com>

Nick <nleioatt at gmail.com> wrote:
>  this is the new oop version, its pretty messy currently, and i do
>  understand it is a simple routine, but i'm using it as an exercise to
>  learn oop python...
> 
>  first the (current) traceback:
>   [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
>  Traceback (most recent call last):
>    File "oop_covariance.py", line 24, in <module>
>      cov = set1.covariance(set2, Eigen_vect.dot)
>    File "/home/nleioatts/python/Eigen.py", line 66, in covariance
>      print self.vectors[i][i]
>  AttributeError: Eigen_vect instance has no attribute '__getitem__'

You are trying to use your Eigen_vect class as an array.  In order for
an object to act as an array it needs a __getitem__ method.

>  class Eigen_vect:
>      def __init__(self, e_val, e_vect):
>          self.e_val  = e_val
>          self.e_vect = e_vect
>      def length(self):
>          return len(self.e_vect)
> 
>      def dot(self, other):
>          d = 0.0
>          if other.length() != self.length():
>              raise ValueError, "Eigen Vectors not same Length"
>          for k in range(self.length()):
>             # print "HI NICK", self.e_vect[k], other.e_vect[k]
>              d += float(self.e_vect[k]) * float(other.e_vect[k])
>          return d

Either add a __getitem__ method like this

    def __getitem__(self, n):
        return self.e_vect[n]

Or you might want to subclass list if you are going to do a lot of
list like operations on Eigen_vects, eg

class Eigen_vect(list):
    def __init__(self, e_val, e_vect):
        self.e_val  = e_val
        self[:] = e_vect

    def dot(self, other):
        d = 0.0
        if len(other) != len(self):
            raise ValueError("Eigen Vectors not same Length")
        for a, b in zip(self, other):
            d += float(a) * float(b)
        return d

Notice that now these things are lists, you can use len, zip etc on
them which makes the code much neater.

e = Eigen_vect(3, range(10))
f = Eigen_vect(4, range(1,11))

print e
print f
print e[2]
print e.dot(f)

Which prints

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
2
330.0

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From robertrobert93 at yahoo.com  Thu Jul 16 16:41:39 2009
From: robertrobert93 at yahoo.com (Robert Robert)
Date: Thu, 16 Jul 2009 13:41:39 -0700 (PDT)
Subject: file write IOError Invalid argument
Message-ID: <505868.24184.qm@web59308.mail.re1.yahoo.com>

Hello All,
I am trying to write a binary string to file on a windows network share. I get an IOError. I've read that it is because the file size is too large. I did a type( binaryString) and saw that it was type "str". So I loop through it one by one element and use f.write to write to file, and it worked without any error. However it took a long while to write to file. I was wondering how I could split this binary string into N number of chunks efficiently and write them to file. 
thanks,

rh 




      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/416bbe22/attachment.html>

From tjreedy at udel.edu  Thu Jul 16 16:42:48 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 16:42:48 -0400
Subject: turtle dump
In-Reply-To: <4A5F287B.2000503@xs4all.nl>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>
Message-ID: <h3o3c9$h7o$1@ger.gmane.org>

Michiel Overtoom wrote:
> 
> I got success with the following code (python 2.6.2):
> 
> import turtle
> turtle.reset()
> for i in range(4):
>    turtle.forward(50)
>    turtle.right(90)
> can=turtle.getscreen().getcanvas()
> can.postscript(file="tmp.ps")

Is raw postscript (.ps) the only thing tk can write from canvas?
I would like to be able to import into OpenOffice document (drawing 
object) and it can import encapsulated postscript (.eps) and about 20 
other things but not, apparently, .ps.

Help on method postscript:
postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance

is spectacularly useless. I did not see anything similar in the list of 
about 100 attributes. The image_type of the canvas is 'photo bitmap' but 
I see no method to write that.




From tjreedy at udel.edu  Thu Jul 16 16:55:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 16:55:08 -0400
Subject: This is a mess...
In-Reply-To: <e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
	<e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
Message-ID: <h3o43e$jj1$1@ger.gmane.org>

Nick wrote:
> this is the new oop version, its pretty messy currently, and i do
> understand it is a simple routine, but i'm using it as an exercise to
> learn oop python...

You neglected to specify Python version.
> 
> first the (current) traceback:
>  [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
> Traceback (most recent call last):
>   File "oop_covariance.py", line 24, in <module>
>     cov = set1.covariance(set2, Eigen_vect.dot)
>   File "/home/nleioatts/python/Eigen.py", line 66, in covariance
>     print self.vectors[i][i]
> AttributeError: Eigen_vect instance has no attribute '__getitem__'

self.vectors[i] is apparently an Eigen_vect instance and you try to 
subscript it, but, as the message said, there is no __getitem__ method.

So add one.


> 
> and a quick explaination:  the file structures aare a 2d list of lists
> of numbers corresponding to eginvectors and a list of numbers
> corresponding to eigenvalues
> 
> #########################33##Here is the main body
> #!/usr/bin/env python
> import sys
> import Eigen
> from Eigen import *
> 
> if len(sys.argv) != 3:
>     print " "
>     print "The corrent usage is 'python covariance.py file1 file2'"
>     print "where the _U.asc and _s.asc will be appended when needed"
>     print " "
>     exit(1)
> file1 =  sys.argv[1]
> file2 =  sys.argv[2]
> set1 = Eigen_set(file1+"_U.asc", file1+"_s.asc")
> set2 = Eigen_set(file2+"_U.asc", file2+"_s.asc")
> cov = set1.covariance(set2, Eigen_vect.dot)
> print cov
> 
> 
> ###############and here are the classes:
> 
> #!/usr/bin/env python
> import sys
> import math
> from math import sqrt
> 
> class Eigen_vect:
>     def __init__(self, e_val, e_vect):
>         self.e_val  = e_val
>         self.e_vect = e_vect
>     def length(self):
>         return len(self.e_vect)

You should really call this __len__ so len(Eigen_vect()) will work.

I presume you need something like
def __getitem__(self, i): return self.e_vect[i]

Before continuing, read the Language Reference / Data Model / Special 
method names to understand how to write classes to integrate into syntax.

Terry Jan Reedy



From pavlovevidence at gmail.com  Thu Jul 16 17:00:43 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 16 Jul 2009 14:00:43 -0700 (PDT)
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
Message-ID: <a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>

On Jul 16, 8:12?am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
wrote:
> Hello everyone,
>
> I am using threading.Condition.wait(timeout) and was surprised to see
> that there is no return value nor an exception when wait() is used w/ a
> timeout. How am I supposed to know if it was notified or if it timed out?

That's a good question.  Condition.wait seems to violate an invariant
if it can return without having acquired the underlying lock.  And if
it does the least it could do is to return a status so you know if you
have to skeddadle.

Workaround is to use the _is_owned() method of Condition to see if you
are the owner of the condition, but this method is undocumented.

cond = Condition()
...
cond.acquire()
while not ok_to_proceed():
    cond.wait()
    if not cond._is_owned():
        # must've timed out
        raise TimeOutException
operate()
cond.release()


Carl Banks


From tjreedy at udel.edu  Thu Jul 16 17:10:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 17:10:15 -0400
Subject: interactive fiction in Python?
In-Reply-To: <853a8wlm25.fsf@agentultra.com>
References: <5c97224b-99d4-469b-90cb-1c04b1e1e9a0@m11g2000yqh.googlegroups.com>
	<853a8wlm25.fsf@agentultra.com>
Message-ID: <h3o4vo$mqb$1@ger.gmane.org>

J Kenneth King wrote:
> George Oliver <georgeoliverGO at gmail.com> writes:
> 
>> hi, I'm just curious who might be working on interactive fiction
>> modules in the style of Inform or TADS for Python. I've seen a few
>> threads on this list [1] (among many that mention IF tangentially),
>> and there are old projects like PUB and PAWS. There are some newer
>> potential projects such as Curveship as well. In any case I'd like to
>> see what's out there.

www.renpy.org

Visual novel engine written in Python, with full access to Python as 
needed. Download includes a tutorial written with renpy. You can look as 
source code in a separate window as you go (at least earlier version I 
used did). Also has 150+ free games/novels to download.

"Ren'Py is a free and cross-platform engine that helps you use words, 
pictures, and sounds to tell stories with the computer."

Terry Jan Reedy



From nobody at nowhere.com  Thu Jul 16 17:12:32 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 22:12:32 +0100
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
	<pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au>
	<401967fb-c12e-4f63-8b05-6dffa0688028@a26g2000yqn.googlegroups.com>
	<028e48c2-4a3a-4920-9a67-d9bb95714b4f@c36g2000yqn.googlegroups.com>
Message-ID: <pan.2009.07.16.21.10.39.985000@nowhere.com>

On Thu, 16 Jul 2009 03:59:47 -0700, Mark wrote:

>> > Or maybe not. If OrderedDicts are sequences as well as mappings, then we
>> > should be able to sort them. And that seems a bit much even for me.

>> One thing that I've just noticed is that you can use <, <=, >=, and >
>> with sets:

>> It seems a bit inconsistent that with sets you always get False when
>> using an ordering operator but with an ordered dict you get an
>> exception?
> 
> Ooops---disregard the above---I forgot that these do subset and
> superset comparisions!

Which is an argument for dictionaries (ordered or not) doing likewise,
except that the comparison would be subfunction rather than subset,
i.e. d1<d2 = all(k in d2 and d2[k] == d1[k] for k in d1).



From mkhitrov at gmail.com  Thu Jul 16 17:22:32 2009
From: mkhitrov at gmail.com (Maxim Khitrov)
Date: Thu, 16 Jul 2009 17:22:32 -0400
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>
References: <mailman.3221.1247757153.8015.python-list@python.org> 
	<a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>
Message-ID: <26ddd1750907161422n5b640a48pbbf9325dd05a699d@mail.gmail.com>

On Thu, Jul 16, 2009 at 5:00 PM, Carl Banks<pavlovevidence at gmail.com> wrote:
> On Jul 16, 8:12?am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
> wrote:
>> Hello everyone,
>>
>> I am using threading.Condition.wait(timeout) and was surprised to see
>> that there is no return value nor an exception when wait() is used w/ a
>> timeout. How am I supposed to know if it was notified or if it timed out?
>
> That's a good question. ?Condition.wait seems to violate an invariant
> if it can return without having acquired the underlying lock. ?And if
> it does the least it could do is to return a status so you know if you
> have to skeddadle.
>
> Workaround is to use the _is_owned() method of Condition to see if you
> are the owner of the condition, but this method is undocumented.
>
> cond = Condition()
> ...
> cond.acquire()
> while not ok_to_proceed():
> ? ?cond.wait()
> ? ?if not cond._is_owned():
> ? ? ? ?# must've timed out
> ? ? ? ?raise TimeOutException
> operate()
> cond.release()

You will always be the owner of the condition whether it times out or
your thread is notified. This doesn't solve the problem. As an aside,
the implementation of wait() is rather poor in any case; the sleep
function should not be used for the purpose of waiting for an event.

Depending on what platform you are using, I can offer two solutions.
The simplest one is to subclass Condition and override the wait
method. Just copy the code as it is, but modify the end of the
function to look like this:

                if not gotit:
                    if __debug__:
                        self._note("%s.wait(%s): timed out", self, timeout)
                    try:
                        self.__waiters.remove(waiter)
                    except ValueError:
                        pass
                    return False
                else:
                    if __debug__:
                        self._note("%s.wait(%s): got it", self, timeout)
                    return True

The two return statements will tell you whether you timed out ("if not
gotit" condition), or were notified ("else").

The better way to solve this and the other problem that I mentioned is
to use native OS events. This is what I had to do for a recent
project. I used pywin32 extension to completely rewrite Event,
Condition, and Timer classes to use a true event-based approach. In
the process of the rewrite I also modified some functionality, such as
returning True of False from wait().

Unfortunately, I'm not able to post this code right now, though I can
try and get permission to do so a bit later. If you are writing
software for Windows, then simply take a look at win32event module.
CreateEvent, SetEvent, ResetEvent, WaitForSingleObject are all the
Windows functions that you need to reimplement threading.Event. Using
the new event class you can implement a proper Condition.wait() method
(hint: use new events rather than locks to wait for notification).

If you are on Linux or BSD, I can't help you. I'm sure that there is
some equivalent functionality that you may be able to access using
ctypes. Exactly how to do it, however, is not something that I can
help you with right now.

- Max


From __peter__ at web.de  Thu Jul 16 17:37:06 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 16 Jul 2009 23:37:06 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
Message-ID: <h3o6hr$mmh$02$1@news.t-online.com>

Terry Reedy wrote:

> Michiel Overtoom wrote:
>> 
>> I got success with the following code (python 2.6.2):
>> 
>> import turtle
>> turtle.reset()
>> for i in range(4):
>>    turtle.forward(50)
>>    turtle.right(90)
>> can=turtle.getscreen().getcanvas()
>> can.postscript(file="tmp.ps")
> 
> Is raw postscript (.ps) the only thing tk can write from canvas?
> I would like to be able to import into OpenOffice document (drawing
> object) and it can import encapsulated postscript (.eps) and about 20
> other things but not, apparently, .ps.
> 
> Help on method postscript:
> postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance
> 
> is spectacularly useless.

http://docs.python.org/library/turtle.html#turtle.getcanvas

The module is a bit messy, but the accompanying documentation seems OK to 
me. 

> I did not see anything similar in the list of
> about 100 attributes. The image_type of the canvas is 'photo bitmap' but
> I see no method to write that.

That's probably a bitmap that you can draw on the canvas. The Canvas is 
actually that of Tkinter, and according to

http://www.tcl.tk/man/tcl8.5/TkCmd/canvas.htm#M59

it writes Encapsulated Postscript 3.0. Also:

$ file tmp.ps
tmp.ps: PostScript document text conforming DSC level 3.0, type EPS

Try changing the file extension from .ps to .eps.

Peter



From emile at fenx.com  Thu Jul 16 17:59:22 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 14:59:22 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.16.20.27.15.563000@nowhere.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<pan.2009.07.16.20.27.15.563000@nowhere.com>
Message-ID: <h3o7md$cf$1@ger.gmane.org>

On 7/16/2009 1:29 PM Nobody said...
> On Wed, 15 Jul 2009 18:14:10 +0200, Hrvoje Niksic wrote:
> 
>>> If the question was "Why is there no 'or' operator ?", would "because
>>> A or B <=> not(not A and not B)" be a proper answer ?
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
> 
> Ah, but it *is* "equivalent"; it isn't "identical", but that's not the
> point.
> 

I'm not sure I'd call it equivalent.  A or B returns either unaltered, 
and not(not A and not B) always returns a boolean.  The equivalent would 
be not(not( A or B )).

Emile



From piet at cs.uu.nl  Thu Jul 16 18:03:52 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 00:03:52 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
Message-ID: <m21voguvxz.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Hello everyone,
>GR> I am using threading.Condition.wait(timeout) and was surprised to see that
>GR> there is no return value nor an exception when wait() is used w/ a timeout.
>GR> How am I supposed to know if it was notified or if it timed out?

Normally you wouldn't have to know. The logic of your program should be
such that you wait until a certain condition is satisfied. After each
wait you usually check that condition anyway, like:

while (some_condition_satisfied):
    cond_var.wait()

The only exception could be if there is a 1-1 relation between a single
waiter and a single notifier. I that case you can usually use if instead
of while (but it does depend of the logic of the notifier).

So in case of using a timeout you can check the desired condition after
the wait and decide what to do. If the condition was not satisfied you
probably want to do something special, like error handling, or do
something else first and then retry the wait.

There could be situations where this doesn't work, however. For example
if you wait until a queue is not empty, and the notify is done when
something is inserted in the queue, another thread may sneak in while
you are waiting and snatch the inserted item just before your thread
continues after the wait. In that case you can't distinguish between a
timeout and a snatcher.

So it all depends on what your use case is.

(Java's wait doesn't return anything either.)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From thelists at optusnet.com.au  Thu Jul 16 18:07:30 2009
From: thelists at optusnet.com.au (Leo List)
Date: 16 Jul 2009 22:07:30 GMT
Subject: Python 3 xmlrpc client HTTPS problem
Message-ID: <4a5fa4a2$0$3321$afc38c87@news.optusnet.com.au>

I have just built and installed version 3.1 and all's good, but when I 
try to connect to a server via HTTPS I get the following:

  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1029, in __call__
    return self.__send(self.__name, args)
  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1271, in 
__request
    verbose=self.__verbose
  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1058, in request
    http_conn = self.send_request(host, handler, request_body, verbose)
  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1183, in 
send_request
    "your version of http.client doesn't support HTTPS")
NotImplementedError: your version of http.client doesn't support HTTPS


I am on Ubuntu and have followed the instructions on how to build a 
release with SSL support:

 ./configure CPPFLAGS=-I/usr/include/openssl LDFLAGS=-L/usr/lib/ssl


Any idea what I'm missing?

Thanks


From piet at cs.uu.nl  Thu Jul 16 18:08:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 00:08:08 +0200
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com>
	<mailman.3236.1247773303.8015.python-list@python.org>
Message-ID: <m2ws68th6f.fsf@cs.uu.nl>

>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:

>a> ok!
>a> I got the indentation errors fixed. Bu I get another error:

>a> Traceback (most recent call last):
>a>   File "./temp.py", line 484, in <module>
>a>     main()
>a>   File "./temp.py", line 476, in main
>a>     line.decode('utf-8').strip()
>a> AttributeError: 'str' object has no attribute 'decode'

>a> I am using Python3.1

In Python 3 you can't decode strings because they are Unicode strings
and it doesn't make sense to decode a Unicode string. You can only
decode encoded things which are byte strings. So you are mixing up byte
strings and Unicode strings.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From pavlovevidence at gmail.com  Thu Jul 16 18:15:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 16 Jul 2009 15:15:52 -0700 (PDT)
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org> 
	<a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com> 
	<mailman.3242.1247779375.8015.python-list@python.org>
Message-ID: <bb4d4dc5-5089-4a0a-a01b-f74efc40702e@i6g2000yqj.googlegroups.com>

On Jul 16, 2:22?pm, Maxim Khitrov <mkhit... at gmail.com> wrote:
> On Thu, Jul 16, 2009 at 5:00 PM, Carl Banks<pavlovevide... at gmail.com> wrote:
> > On Jul 16, 8:12?am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
> > wrote:
> >> Hello everyone,
>
> >> I am using threading.Condition.wait(timeout) and was surprised to see
> >> that there is no return value nor an exception when wait() is used w/ a
> >> timeout. How am I supposed to know if it was notified or if it timed out?
>
> > That's a good question. ?Condition.wait seems to violate an invariant
> > if it can return without having acquired the underlying lock. ?And if
> > it does the least it could do is to return a status so you know if you
> > have to skeddadle.
>
> > Workaround is to use the _is_owned() method of Condition to see if you
> > are the owner of the condition, but this method is undocumented.
>
> > cond = Condition()
> > ...
> > cond.acquire()
> > while not ok_to_proceed():
> > ? ?cond.wait()
> > ? ?if not cond._is_owned():
> > ? ? ? ?# must've timed out
> > ? ? ? ?raise TimeOutException
> > operate()
> > cond.release()
>
> You will always be the owner of the condition whether it times out or
> your thread is notified. This doesn't solve the problem.

You are correct, I misread the code.  So scratch what I said.


Carl Banks


From akhilanger at gmail.com  Thu Jul 16 18:43:37 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 15:43:37 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <m2ws68th6f.fsf@cs.uu.nl>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
Message-ID: <24525761.post@talk.nabble.com>


Then, how should I do it?
I read a byte string from sys.stdin which needs to converted to unicode
string for further processing. I cannot just remove the decode statement and
proceed?

This is it what it looks like:

for line in sys.stdin:
    line = line.decode('utf-8').strip()
    if line == '<page>': #do something here
    elsif #do something here
    
If I remove the decode statement, line == '<page>' never gets true. 

--Akhil


Piet van Oostrum wrote:
> 
>>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:
> 
>>a> ok!
>>a> I got the indentation errors fixed. Bu I get another error:
> 
>>a> Traceback (most recent call last):
>>a>   File "./temp.py", line 484, in <module>
>>a>     main()
>>a>   File "./temp.py", line 476, in main
>>a>     line.decode('utf-8').strip()
>>a> AttributeError: 'str' object has no attribute 'decode'
> 
>>a> I am using Python3.1
> 
> In Python 3 you can't decode strings because they are Unicode strings
> and it doesn't make sense to decode a Unicode string. You can only
> decode encoded things which are byte strings. So you are mixing up byte
> strings and Unicode strings.
> -- 
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24525761.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From tjreedy at udel.edu  Thu Jul 16 19:06:55 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 19:06:55 -0400
Subject: turtle dump
In-Reply-To: <h3o6hr$mmh$02$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com>
Message-ID: <h3obqg$aru$1@ger.gmane.org>

Peter Otten wrote:
> Terry Reedy wrote:

>> Help on method postscript:
>> postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance
>>
>> is spectacularly useless.

This is from interactive help.

> http://docs.python.org/library/turtle.html#turtle.getcanvas

That method, following your lead, is how I got to .postscript.
The doc says

" Return the Canvas of this TurtleScreen. Useful for insiders who know 
what to do with a Tkinter Canvas."

> The module is a bit messy, but the accompanying documentation seems OK to 
> me. 

?? I am not an 'insider' ;-).

>> I did not see anything similar in the list of
>> about 100 attributes. 

Of Canvas, mostly methods. I can understand that no one who could write 
decent doc strings for the 100 methods has actually volunteered to do so.

>The image_type of the canvas is 'photo bitmap' but
>> I see no method to write that.
> 
> That's probably a bitmap that you can draw on the canvas. The Canvas is 
> actually that of Tkinter, and according to
> 
> http://www.tcl.tk/man/tcl8.5/TkCmd/canvas.htm#M59
> 
> it writes Encapsulated Postscript 3.0. Also:
> 
> $ file tmp.ps
> tmp.ps: PostScript document text conforming DSC level 3.0, type EPS
> 
> Try changing the file extension from .ps to .eps.

I will. Thank you.

tjr



From graham.dumpleton at gmail.com  Thu Jul 16 19:25:37 2009
From: graham.dumpleton at gmail.com (Graham Dumpleton)
Date: Thu, 16 Jul 2009 16:25:37 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com> 
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com> 
	<4a5ea61b$0$1682$742ec2ed@news.sonic.net>
	<0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>
	<4a5eb46a$0$1673$742ec2ed@news.sonic.net>
Message-ID: <ed921183-e5de-4d1c-b9f3-cb85d880bcf0@x5g2000prf.googlegroups.com>

On Jul 16, 3:05?pm, John Nagle <na... at animats.com> wrote:
> alex23 wrote:
> > On Jul 16, 2:03 pm, John Nagle <na... at animats.com> wrote:
> >> ? ? ?"fcgi" is an option for this sort of thing. ?With "mod_fcgi" installed
> >> in Apache, and "fcgi.py" used to manage the Python side of the problem, you
> >> can have semi-persistent programs started up and shut down for you on the
> >> server side.
>
> > Hey John,
>
> > The environments in which I've been asked to develop webs apps using
> > Python have all utilisedmod_wsgi. Do you have any experience with
> >mod_wsgivs mod_fcgi, and if so, can you comment on any relevant
> > performance / capability / ease-of-use differences?
>
> > Cheers,
> > alex23
>
> ? ? FCGI seems to be somewhat out of favor, perhaps because it isn't
> complicated enough.

I doubt that is the reason. It is out of favour for Python web hosting
at least, because web hosting companies provide really crappy support
for using Python with it and also don't like long lived processes.
Most FASTCGI deployments are configured in a way more appropriate for
PHP because that is what the default settings favour. This works to
the detriment of Python. Even when people setup FASTCGI themselves,
they still don't play with the configuration to optimise it for their
specific Python application. Thus it can still run poorly.

> It's a mature technology and works reasonably well.

But is showing its age. It really needs a refresh. Various of its
design decisions were from when network speeds and bandwidth were much
lower and this complicates the design. Making the protocol format
simpler in some areas would make it easier to implement. The protocol
could also be built on to make process management more flexible,
rather than relying on each implementation to come up with adhoc ways
of managing it.

Part of the problem with FASTCGI, or hosting of dynamic applications
in general, is that web servers primary focus is serving of static
files. Any support for dynamic web applications is more of a bolt on
feature. Thus, web applications using Python will always be at a
disadvantage. PHP manages okay because their model of operation is
closer to the one shot processing of static files. Python requires
persistent to work adequately with modern fat applications.

> It's been a puzzle to me that FCGI was taken out of the
> main Apache code base, because it gives production-level performance
> with CGI-type simplicity.

As far as I know FASTCGI support has in the past never been a part of
the Apache code base. Both mod_fastcgi and mod_fcgid were developed by
independent people and not under the ASF.

In Apache 2.3 development versions (to become 2.4 when released),
there will however be a mod_proxy_fcgi. The ASF has also taken over
management of mod_fcgid and working out how that may be incorporated
into future Apache versions.

> ? ? WSGI has a mode for running Python inside the Apache process,
> which is less secure and doesn't allow multiple Python processes.

Depending on the requirements it is more than adequate and if
configured correctly gives better performance and scalability. Not
everyone runs in a shared hosting environment. The different modes of
mod_wsgi therefore give choice.

> That complicates mod_wsgi considerably,

No it doesn't. It is actual daemon mode that complicates things, not
embedded mode.

> and ties it very closely
> to specific versions of Python and Python modules. ?As a result,
> the WSGI developers are patching at a great rate.

What are you talking about when you say 'As a result, the WSGI
developers are patching at a great rate'? As with some of your other
comments, this is leaning towards being FUD and nothing more. There is
no 'patching at a great rate' going on.

>?I think the thing has too many "l33t features".

It is all about choice and providing flexibility. You may not see a
need for certain features, but it doesn't mean other people don't have
a need for it.

> I'd avoid "embedded mode". ?"Daemon mode" is the way to go if you use WSGI.

I'd agree, but not sure you really understand the reasons for why it
would be preferred.

> I haven't tried WSGI;

Then why comment on it as if you are knowledgeable on it.

> I don't need the grief of a package under heavy development.

More FUD.

Graham


From ben+python at benfinney.id.au  Thu Jul 16 19:56:33 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 09:56:33 +1000
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
Message-ID: <87zlb4gp1q.fsf@benfinney.id.au>

Inky 788 <inky788 at gmail.com> writes:

> On Jul 10, 7:35?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> > Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
> > with a simple imperative::
> >
> > ? ? Use 4 spaces per indentation level.
> 
> That actually sounds pretty weird. "Don't do {foo}. Really, I mean
> *really* don't do {foo}. Oh, also, the interpreter allows you to do
> {foo}. But don't do it! I mean it!".

Not weird at all, especially when you realise that your interpretation
isn't there in the document.

The allowance for both types of indentation is a compromise made for
backward compatibility with code written before this convention was
quite so strong. All *new* code is strongly advised to follow the
convention, while the interpreter will still allow old code that doesn't
follow the convention.

> Very ... perlish, if you ask me.

Hah! Perl doesn't have the ?don't do {foo}? part, so I don't see what
you're seeing.

-- 
 \      ?I like to skate on the other side of the ice.? ?Steven Wright |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From lhughes42 at gmail.com  Thu Jul 16 19:58:36 2009
From: lhughes42 at gmail.com (lh)
Date: Thu, 16 Jul 2009 16:58:36 -0700 (PDT)
Subject: Visualization of Python Class Hierarchy
Message-ID: <e55e6100-48a6-445d-a122-b61db94b8556@f20g2000prn.googlegroups.com>

I would like to automatically generate this for my program. I am
running python in  an eclipse context (pydev).  I am not familiar with
the best current tools.
 Thank you


From wuwei23 at gmail.com  Thu Jul 16 20:37:00 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 17:37:00 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it> 
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it> 
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com> 
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org> 
	<h3o6hr$mmh$02$1@news.t-online.com>
	<mailman.3245.1247785636.8015.python-list@python.org>
Message-ID: <364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>

> >> Help on method postscript:
> >> postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance
> >> is spectacularly useless.
>
> This is from interactive help.

The help in iPython says the same, but also mentions that it's a
dynamically generated function, so it may not be picking up the
docstring that way. turtle.ScrolledCanvas.postscript is similarly
terse, but you can find more info in turtle.Canvas.postscript:

  Print the contents of the canvas to a postscript
  file. Valid options: colormap, colormode, file, fontmap,
  height, pageanchor, pageheight, pagewidth, pagex, pagey,
  rotate, witdh, x, y.

> The doc says
>
> " Return the Canvas of this TurtleScreen. Useful for insiders who know
> what to do with a Tkinter Canvas."
>
> > The module is a bit messy, but the accompanying documentation seems OK to
> > me.
>
> ?? I am not an 'insider' ;-).

I don't think the intent of the turtle module is to be a primer in Tk,
but more of an educational tool. The lack of image export niceties has
a lot to do with the limitations of Tk, but was probably (and I'm
conjecturing here) felt to be outside the scope of what the module
aims to achieve.

> Of Canvas, mostly methods. I can understand that no one who could write
> decent doc strings for the 100 methods has actually volunteered to do so.

I think they all _have_ doc strings, or at least the code they
eventually call does, but I'd have to look into the module itself to
see if they could be brought over dynamically.

You may be interested in the final page of Greg Lingl's PyCon talk,
Seven Ways to use Turtle[1] which states:

  The turtle module is designed in a way so that essentially all of
the turtle
  graphics machinery is based on a class TurtleScreenBase, which
provides the
  interface to the underlying graphics toolkit Tkinter.

  So it?s easy to port turtle.py to different graphics toolkits/
libraries,
  simply by replacing this Tkinter base class with an appropriate
different one.

  I?ve done two ports: Pygame & Jython

If you're after bitmap, I'd suggest contacting Greg and asking about
the Pygame port. His contact info can be found at the original site
for the revised turtle module[2], hopefully it's still up to date.

1: us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-
PyCon2007.pdf
2: http://xturtle.rg16.at/download.html


From tjreedy at udel.edu  Thu Jul 16 20:55:54 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 20:55:54 -0400
Subject: turtle dump
In-Reply-To: <h3obqg$aru$1@ger.gmane.org>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>	<h3o6hr$mmh$02$1@news.t-online.com>
	<h3obqg$aru$1@ger.gmane.org>
Message-ID: <h3oi6r$o6o$1@ger.gmane.org>

Terry Reedy wrote:

>> $ file tmp.ps
>> tmp.ps: PostScript document text conforming DSC level 3.0, type EPS
>>
>> Try changing the file extension from .ps to .eps.
> 
> I will. Thank you.

I tried it. Unfortunately, OOo does not open it correctly. It just 
displays the first three lines of metadate - Title, Creator, Date -- as 
image text. Photoshop does read the image, and does an ok job of 
conversion once anti-aliasing is turned off.

Hmmm. Crazy idea... in
http://us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-PyCon2007.pdf
Gregor Lingl says that turtle.py has been ported to pygame and jython as 
back ends. It should be possible to instead send output to a file 
instead of an on-screen canvas. Run a program to screen. When output 
looks right, return with a different parameter to send to file.

For instance, an OpenDocumentDrawing file (.odd) using odfpy.
This assumes that there are elements corresponding to each turtle 
command. Or at least that the fit is close enough.

Terry Jan Reedy



From ronn.ross at gmail.com  Thu Jul 16 20:57:03 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Thu, 16 Jul 2009 20:57:03 -0400
Subject: TypeError: unbound method
Message-ID: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>

Hello all,

Created a python file that has a class and three methods. When I jump into
interactive mode I import like so:

from <file> import <class>

Now when I try to use a method from the class:

var1 = class.method()

It give me this error:
TypeError: unbound method <methodname> must be called with <classname>
instance as first argument (got int instance instead)

I'm not sure what is going on event after consulting with google
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/3a52d02f/attachment.html>

From ben+python at benfinney.id.au  Thu Jul 16 21:01:49 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 11:01:49 +1000
Subject: Override a method but inherit the docstring
Message-ID: <87r5wggm0y.fsf@benfinney.id.au>

Howdy all,

The following is a common idiom::

    class FooGonk(object):
        def frobnicate(self):
            """ Frobnicate this gonk. """
            basic_implementation(self.wobble)

    class BarGonk(FooGonk):
        def frobnicate(self):
            special_implementation(self.warble)

The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
the method, the original docstring is not associated with it.

Ideally there would be a way to specify that the docstring should be
inherited. The best I can come up with is::

    class BarGonk(FooGonk):
        def frobnicate(self):
            special_implementation(self.warble)
        frobnicate.__doc__ = FooGonk.frobnicate.__doc__

but that violates DRY (the association between BarGonk and FooGonk is
being repeated), puts the docstring assignment awkwardly after the end
of the method instead of at the beginning where docstrings normally go,
and reads poorly besides.

What is the most Pythonic, DRY-adherent, and preferably least-ugly
approach to override a method, but have the same docstring on both
methods?

-- 
 \           ?Why, I'd horse-whip you if I had a horse.? ?Groucho Marx |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From clp2 at rebertia.com  Thu Jul 16 21:08:45 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 18:08:45 -0700
Subject: TypeError: unbound method
In-Reply-To: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>
References: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>
Message-ID: <50697b2c0907161808i3bcc55eej333ad83660897313@mail.gmail.com>

On Thu, Jul 16, 2009 at 5:57 PM, Ronn Ross<ronn.ross at gmail.com> wrote:
> Hello all,
>
> Created a python file that has a class and three methods. When I jump into
> interactive mode I import like so:
>
> from <file> import <class>
>
> Now when I try to use a method from the class:
>
> var1 = class.method()
>
> It give me this error:
> TypeError: unbound method <methodname> must be called with <classname>
> instance as first argument (got int instance instead)
>
> I'm not sure what is going on event after consulting with google

You're trying to call an instance method on the class itself, which
doesn't make sense.
You need to first create an instance of the class to invoke the method on.
i.e.:

instance = TheClass(constuctor_arguments_here)
var1 = instance.method()

Cheers,
Chris
-- 
http://blog.rebertia.com


From exarkun at divmod.com  Thu Jul 16 21:13:34 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Thu, 16 Jul 2009 21:13:34 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <20090717011334.2543.775231474.divmod.quotient.2982@henry.divmod.com>

On Fri, 17 Jul 2009 11:01:49 +1000, Ben Finney <ben+python at benfinney.id.au> wrote:
>Howdy all,
>
>The following is a common idiom::
>
>    class FooGonk(object):
>        def frobnicate(self):
>            """ Frobnicate this gonk. """
>            basic_implementation(self.wobble)
>
>    class BarGonk(FooGonk):
>        def frobnicate(self):
>            special_implementation(self.warble)
>
>The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>the method, the original docstring is not associated with it.
>
>Ideally there would be a way to specify that the docstring should be
>inherited. The best I can come up with is::
>
>    class BarGonk(FooGonk):
>        def frobnicate(self):
>            special_implementation(self.warble)
>        frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>
>but that violates DRY (the association between BarGonk and FooGonk is
>being repeated), puts the docstring assignment awkwardly after the end
>of the method instead of at the beginning where docstrings normally go,
>and reads poorly besides.
>
>What is the most Pythonic, DRY-adherent, and preferably least-ugly
>approach to override a method, but have the same docstring on both
>methods?
>

How about this?

    class BarGonk(FooGonk):
        @inherit_docstring
        def frobnicate(self):
            special_implementation(self.warble)

The implementation of "inherit_docstring" is left as an exercise for the
reader (it's not utterly trivial, I admit, as "FooGonk" will not readily
be at hand, but it is still possible).

By the way, I don't think this is a particularly good idea.  Presumably
there is a reason your implementation is special.  It would probably be
better if this were reflected in the docstring somehow.  Perhaps this
idea is a better one:

    class BarGonk(FooGonk):
        @append_to_docstring
        def frobnicate(self):
            """
            This implementation takes the warble into consideration.
            """
            special_implementation(self.warble)

With the result of BarGonk.frobnicate.__doc__ being set to:


     Frobnicate this gonk.

     This implementation takes the warble into consideration.

Jean-Paul


From nobody at nowhere.com  Thu Jul 16 21:16:53 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 17 Jul 2009 02:16:53 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<pan.2009.07.16.20.27.15.563000@nowhere.com>
	<mailman.3243.1247781407.8015.python-list@python.org>
Message-ID: <pan.2009.07.17.01.15.01.688000@nowhere.com>

On Thu, 16 Jul 2009 14:59:22 -0700, Emile van Sebille wrote:

>>>> If the question was "Why is there no 'or' operator ?", would "because
>>>> A or B <=> not(not A and not B)" be a proper answer ?
>>> Note that in Python A or B is in fact not equivalent to not(not A and
>>> not B).
>> 
>> Ah, but it *is* "equivalent"; it isn't "identical", but that's not the
>> point.
> 
> I'm not sure I'd call it equivalent.

That depends upon what definition of "equivalent" you are using. Apart
from all manner of vague, informal definitions, there is a formal
definition:

A relation "=" is an equivalence relation if the following hold for all
x, y, and z:

	x = x
	x = y => y = x
	x = y and y = z => x = z

An equivalence relation partitions its domain into equivalence classes,
such that an element is "=" (equivalent) to every element in the same
class, and not "=" to every element in every other class.

This is a lesser notion of equality to "identity", which also requires
that x = y => f(x) = f(y) for all f.

Python's notion of boolean values treats x and y as equivalent if
bool(x) == bool(y).

On this basis, the result of "A or B" is *equivalent* to the result of
"not(not A and not B)". If you use either result as a boolean value (e.g.
the test of an "if" or "while" statement, as an operand to "and" or "or",
etc), the effect is the same. The results aren't *identical*, as there
exist ways to distinguish the two.

As for the utility of this behaviour, returning an actual value rather
than True/False allows the operators to be used as "gates". The term
"gate" in digital logic follows from the axioms: 

	0 and x = 0
	1 and x = x

	0 or x = x
	1 or x = 1

[0 = False, 1 = True]

If you consider the left operand as the "control" and the right operand as
the "data", the control determines whether or not the data can pass
through the gate to the output (i.e. whether the gate is open or closed).

In Python:

and:
	False and 7	=> False
	False and 0	=> False
	True and 7	=> 7
	True and 0	=> 0

or:
	False or 7	=> 7
	False or 0	=> 0
	True or 7	=> True
	True or 0	=> True




From max at alcyone.com  Thu Jul 16 21:18:56 2009
From: max at alcyone.com (Erik Max Francis)
Date: Thu, 16 Jul 2009 18:18:56 -0700
Subject: Einstein summation notation (was: question of style)
In-Reply-To: <kmr2uu.d1t@spenarnc.xs4all.nl>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
Message-ID: <Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>

Albert van der Horst wrote:
> Einstein introduced the summation convention for indices that
> are used twice. Leaving out summation signs is absolutely hideous,
> but it has saved generations of physicists of loosing track (and
> their minds.)

There is a joke among mathematicians that if Einstein hadn't been 
remembered for a couple of other fairly contributions things in physics 
:-), he would have been remembered in mathematics for that convention, 
since it has saved everyone -- mathematicians included -- a lot of time 
and anguish.  When using tensor calculus, there's even very easy ways to 
verify you have a valid tensor equation using it.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   If the sky should fall, hold up your hands.
    -- (a Spanish proverb)


From mkhitrov at gmail.com  Thu Jul 16 21:21:16 2009
From: mkhitrov at gmail.com (Maxim Khitrov)
Date: Thu, 16 Jul 2009 21:21:16 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <20090717011334.2543.775231474.divmod.quotient.2982@henry.divmod.com>
References: <87r5wggm0y.fsf@benfinney.id.au>
	<20090717011334.2543.775231474.divmod.quotient.2982@henry.divmod.com>
Message-ID: <26ddd1750907161821r1a5feeebr1c7c63e0130bf6e7@mail.gmail.com>

On Thu, Jul 16, 2009 at 9:13 PM, Jean-Paul Calderone<exarkun at divmod.com> wrote:
> On Fri, 17 Jul 2009 11:01:49 +1000, Ben Finney <ben+python at benfinney.id.au>
> wrote:
>>
>> Howdy all,
>>
>> The following is a common idiom::
>>
>> ? class FooGonk(object):
>> ? ? ? def frobnicate(self):
>> ? ? ? ? ? """ Frobnicate this gonk. """
>> ? ? ? ? ? basic_implementation(self.wobble)
>>
>> ? class BarGonk(FooGonk):
>> ? ? ? def frobnicate(self):
>> ? ? ? ? ? special_implementation(self.warble)
>>
>> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>> the method, the original docstring is not associated with it.
>>
>> Ideally there would be a way to specify that the docstring should be
>> inherited. The best I can come up with is::
>>
>> ? class BarGonk(FooGonk):
>> ? ? ? def frobnicate(self):
>> ? ? ? ? ? special_implementation(self.warble)
>> ? ? ? frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>>
>> but that violates DRY (the association between BarGonk and FooGonk is
>> being repeated), puts the docstring assignment awkwardly after the end
>> of the method instead of at the beginning where docstrings normally go,
>> and reads poorly besides.
>>
>> What is the most Pythonic, DRY-adherent, and preferably least-ugly
>> approach to override a method, but have the same docstring on both
>> methods?
>>
>
> How about this?
>
> ? class BarGonk(FooGonk):
> ? ? ? @inherit_docstring
> ? ? ? def frobnicate(self):
> ? ? ? ? ? special_implementation(self.warble)
>
> The implementation of "inherit_docstring" is left as an exercise for the
> reader (it's not utterly trivial, I admit, as "FooGonk" will not readily
> be at hand, but it is still possible).
>
> By the way, I don't think this is a particularly good idea. ?Presumably
> there is a reason your implementation is special. ?It would probably be
> better if this were reflected in the docstring somehow. ?Perhaps this
> idea is a better one:
>
> ? class BarGonk(FooGonk):
> ? ? ? @append_to_docstring
> ? ? ? def frobnicate(self):
> ? ? ? ? ? """
> ? ? ? ? ? This implementation takes the warble into consideration.
> ? ? ? ? ? """
> ? ? ? ? ? special_implementation(self.warble)
>
> With the result of BarGonk.frobnicate.__doc__ being set to:
>
>
> ? ?Frobnicate this gonk.
>
> ? ?This implementation takes the warble into consideration.

Another way is to use a metaclass. Have its __new__ method loop
through all attributes and compare those with what is already defined
in bases. If you find a match, copy the __doc__ attribute. The
advantage here is that it will work for all methods without any
additional code, not counting the "__metaclass__ = ..." line. If you
define a metaclass for the base, then no modifications are required
for any subclasses. I do agree, however, that the best thing to do is
to write a very short explanation for what the override is for.

- Max


From nobody at nowhere.com  Thu Jul 16 21:23:41 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 17 Jul 2009 02:23:41 +0100
Subject: UnicodeEncodeError: 'ascii' codec can't encode character	u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<mailman.3244.1247784220.8015.python-list@python.org>
Message-ID: <pan.2009.07.17.01.21.48.641000@nowhere.com>

On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:

>> In Python 3 you can't decode strings because they are Unicode strings
>> and it doesn't make sense to decode a Unicode string. You can only
>> decode encoded things which are byte strings. So you are mixing up byte
>> strings and Unicode strings.
>
> Then, how should I do it?
> I read a byte string from sys.stdin which needs to converted to unicode
> string for further processing.

In 3.x, sys.stdin (stdout, stderr) are text streams, which means that they
read and write Unicode strings, not byte strings.

> I cannot just remove the decode statement and
> proceed?
> 
> This is it what it looks like:
> 
> for line in sys.stdin:
>     line = line.decode('utf-8').strip()
>     if line == '<page>': #do something here
>     elsif #do something here
>     
> If I remove the decode statement, line == '<page>' never gets true. 

Did you inadvertently remove the strip() as well?



From rhodri at wildebst.demon.co.uk  Thu Jul 16 21:31:43 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 17 Jul 2009 02:31:43 +0100
Subject: Override a method but inherit the docstring
In-Reply-To: <87r5wggm0y.fsf@benfinney.id.au>
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <op.uw6ui5w8a8ncjz@gnudebst>

On Fri, 17 Jul 2009 02:01:49 +0100, Ben Finney  
<ben+python at benfinney.id.au> wrote:

> Howdy all,
>
> The following is a common idiom::
>
>     class FooGonk(object):
>         def frobnicate(self):
>             """ Frobnicate this gonk. """
>             basic_implementation(self.wobble)
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
>
> Ideally there would be a way to specify that the docstring should be
> inherited. The best I can come up with is::
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>         frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>
> but that violates DRY (the association between BarGonk and FooGonk is
> being repeated),

Not really.  Consider the case of BarGonk being a subclass of FooGonk
and BazGonk; which docstring would you wish to inherit?

> puts the docstring assignment awkwardly after the end
> of the method instead of at the beginning where docstrings normally go,
> and reads poorly besides.

Sounds like a job for a decorator!

(This is probably unbelievably ugly and unwise, since I don't use
decorators at all often.)

def copydoc(cls):
     def _fn(fn):
         if fn.__name__ in cls.__dict__:
             fn.__doc__ = cls.__dict__[fn.__name__].__doc__
         return fn
     return _fn

class BarGonk(FooGonk):
     @copydoc(FooGonk)
     def frobnicate(self):
         special_implementation(self.warble)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From ptmcg at austin.rr.com  Thu Jul 16 21:35:05 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Thu, 16 Jul 2009 18:35:05 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>

On Jul 16, 8:01?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Howdy all,
>
> The following is a common idiom::
>
> ? ? class FooGonk(object):
> ? ? ? ? def frobnicate(self):
> ? ? ? ? ? ? """ Frobnicate this gonk. """
> ? ? ? ? ? ? basic_implementation(self.wobble)
>
> ? ? class BarGonk(FooGonk):
> ? ? ? ? def frobnicate(self):
> ? ? ? ? ? ? special_implementation(self.warble)
>
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
>
> What is the most Pythonic, DRY-adherent, and preferably least-ugly
> approach to override a method, but have the same docstring on both
> methods?
>

Two ideas come to mind, the decorator way and the metaclass way.  I am
not a guru at either, but these two examples work:

# the decorator way
def inherit_docstring_from(cls):
    def docstring_inheriting_decorator(fn):
        fn.__doc__ = getattr(cls,fn.__name__).__doc__
        return fn
    return docstring_inheriting_decorator


class FooGonk(object):
    def frobnicate(self):
        """ Frobnicate this gonk. """
        basic_implementation(self.wobble)


class BarGonk(FooGonk):
    @inherit_docstring_from(FooGonk)
    def frobnicate(self):
        special_implementation(self.warble)

bg = BarGonk()
help(bg.frobnicate)

Prints:
Help on method frobnicate in module __main__:

frobnicate(self) method of __main__.BarGonk instance
    Frobnicate this gonk.


Using a decorator in this manner requires repeating the super class
name.  Perhaps there is a way to get the bases of BarGonk, but I don't
think so, because at the time that the decorator is called, BarGonk is
not yet fully defined.



# The metaclass way

from types import FunctionType

class DocStringInheritor(type):
    def __new__(meta, classname, bases, classDict):
        newClassDict = {}
        for attributeName, attribute in classDict.items():
            if type(attribute) == FunctionType:
                # look through bases for matching function by name
                for baseclass in bases:
                    if hasattr(baseclass, attributeName):
                        basefn = getattr(baseclass,attributeName)
                        if basefn.__doc__:
                            attribute.__doc__ = basefn.__doc__
                            break

            newClassDict[attributeName] = attribute

        return type.__new__(meta, classname, bases, newClassDict)

class FooGonk2(object):
    def frobnicate(self):
        """ Frobnicate this gonk. """
        basic_implementation(self.wobble)


class BarGonk2(FooGonk2):
    __metaclass__ = DocStringInheritor
    def frobnicate(self):
        special_implementation(self.warble)

bg = BarGonk2()
help(bg.frobnicate)

Prints:

Help on method frobnicate in module __main__:

frobnicate(self) method of __main__.BarGonk2 instance
    Frobnicate this gonk.


This metaclass will walk the list of bases until the desired
superclass method is found AND if that method has a docstring and only
THEN does it attach the superdocstring to the derived class method.

Please use carefully, I just did the metaclass thing by following
Michael Foord's Metaclass tutorial (http://www.voidspace.org.uk/python/
articles/metaclasses.shtml), I may have missed a step or two.

-- Paul


From vinay_sajip at yahoo.co.uk  Thu Jul 16 21:56:51 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Thu, 16 Jul 2009 18:56:51 -0700 (PDT)
Subject: ANN: gnupg v0.2.0 released
Message-ID: <mailman.3256.1247799947.8015.python-announce-list@python.org>

A new version of the Python module which wraps GnuPG has been
released.

What Changed?
=============
The module was refactored slightly to support Python 3.0.

The current version now passes all tests on Windows (Python 2.4, 2.5)
and Ubuntu (Python 2.4, 2.5, 2.6 and 3.0).

What Does It Do?
================
The gnupg module allows Python programs to make use of the
functionality provided by the Gnu Privacy Guard (abbreviated GPG or
GnuPG). Using this module, Python programs can encrypt and decrypt
data, digitally sign documents and verify digital signatures, manage
(generate, list and delete) encryption keys, using proven Public Key
Infrastructure (PKI) encryption technology based on OpenPGP.

This module is expected to be used with Python versions >= 2.4, as it
makes use of the subprocess module which appeared in that version of
Python. This module is a newer version derived from earlier work by
Andrew Kuchling, Richard Jones and Steve Traugott.

A test suite using unittest is included with the source distribution.

Simple usage:

>>> import gnupg
>>> gpg = gnupg.GPG(gnupghome='/path/to/keyring/directory')
>>> gpg.list_keys()
[{
  ...
  'fingerprint': 'F819EE7705497D73E3CCEE65197D5DAC68F1AAB2',
  'keyid': '197D5DAC68F1AAB2',
  'length': '1024',
  'type': 'pub',
  'uids': ['', 'Gary Gross (A test user) <gary.gross at gamma.com>']},
 {
  ...
  'fingerprint': '37F24DD4B918CC264D4F31D60C5FEFA7A921FC4A',
  'keyid': '0C5FEFA7A921FC4A',
  'length': '1024',
  ...
  'uids': ['', 'Danny Davis (A test user) <danny.davis at delta.com>']}]
>>> encrypted = gpg.encrypt("Hello, world!", ['0C5FEFA7A921FC4A'])
>>> str(encrypted)
'-----BEGIN PGP MESSAGE-----\nVersion: GnuPG v1.4.9 (GNU/Linux)\n
\nhQIOA/6NHMDTXUwcEAf
...
-----END PGP MESSAGE-----\n'
>>> decrypted = gpg.decrypt(str(encrypted), passphrase='secret')
>>> str(decrypted)
'Hello, world!'
>>> signed = gpg.sign("Goodbye, world!", passphrase='secret')
>>> verified = verified = gpg.verify(str(signed))
>>> print "Verified" if verified else "Not verified"
'Verified'

For more information, visit http://code.google.com/p/python-gnupg/ -
as always, your feedback is most welcome (especially bug reports,
patches and suggestions for improvement). Enjoy!

Cheers

Vinay Sajip
Red Dove Consultants Ltd.


From tismer at stackless.com  Thu Jul 16 22:26:02 2009
From: tismer at stackless.com (Christian Tismer)
Date: Fri, 17 Jul 2009 04:26:02 +0200
Subject: ANN: psyco V2
Message-ID: <4A5FE13A.3080708@stackless.com>

Announcing Psyco V2 source release
----------------------------------

This is the long awaited announcement of Psyco V2.

Psyco V2 is a continuation of the well-known psyco project,
which was called finished and was dis-continued by its author
Armin Rigo in 2005, in favor of the PyPy project.

This is a new project, using Psyco's code base with permission
of Armin. Questions aqnd complaints should go to me
(tismer at stackless.com) or the mailing list
(psyco-devel at lists.sourceforge.net);
Armin is explicitly not in charge of (t)his project any longer!

As one of the founders and an active member of the PyPy
project, I was very happy to be invited to work on Psyco
V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
approach "an extension module that just makes Python faster".

Psyco is a just-in-time compiler that accelerates arbitrary
Python code by specialization. We believe that Psyco's approach
can be carried out much further than it was tried so far, when
it's first version was abandoned.

This first V2 release is source-only. There is no web-site, yet,
and there are no binaries for download. These will be available
in a few days on http://www.psyco.org .

For the time being, please stick with subversion access,
building the extension module from source code. The repository
is here:

     http://codespeak.net/svn/psyco/v2/dist

Check-out the repository, and run the setup.py script,
given that you have access to a C compiler.

Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
and Mac OS X. Psyco is not supporting 64 bit, yet. But it
is well being considered.

The current improvements are, shortly:

   - Support for Python 2.4, 2.5 and 2.6
   - a lot of new builtins
   - generators, fast and fully supported.

More information is coming soon on http://www.psyco.org .

This is the beginning of a series of new Psyco versions.
Many more improvements are prepared and about to be published,
soon, starting with the current version 2.0.0 .

Stay tuned, this is just the beginning of psyco's re-birth!

For questions about Psyco V2, please join the mailing list

     psyco-devel at lists.sourceforge.net

or contact me on IRC:

     #psyco on irc.freenode.net .

Psyco V2 is fundamentally supported by FATTOC, LLC.
See http://www.fattoc.com .

Without their continuous support, this work would not have
been possible at all. I wish to express my deepest thanks
to FATTOC, for allowing me to continue on Psyco with all the
energy that this ambitious project needs, and will need.

Further special thanks are going to
Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
Raymond Hettinger, Fabrizio Milo, Michael Foord,
Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
for all the support and discussions.

Looking forward to a great future of Psyco!

July 17, 2009
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From tismer at stackless.com  Thu Jul 16 22:48:18 2009
From: tismer at stackless.com (Christian Tismer)
Date: Fri, 17 Jul 2009 04:48:18 +0200
Subject: ANN: psyco V2
Message-ID: <4A5FE672.3000401@stackless.com>

Announcing Psyco V2 source release
----------------------------------

This is the long awaited announcement of Psyco V2.

Psyco V2 is a continuation of the well-known psyco project,
which was called finished and was dis-continued by its author
Armin Rigo in 2005, in favor of the PyPy project.

This is a new project, using Psyco's code base with permission
of Armin. Questions and complaints should go to me
(tismer at stackless.com) or the mailing list
(psyco-devel at lists.sourceforge.net);
Armin is explicitly not in charge of (t)his project any longer!

As one of the founders and an active member of the PyPy
project, I was very happy to be invited to work on Psyco
V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
approach "an extension module that just makes Python faster".

Psyco is a just-in-time compiler that accelerates arbitrary
Python code by specialization. We believe that Psyco's approach
can be carried out much further than it was tried so far, when
it's first version was abandoned.

This first V2 release is source-only. There is no web-site, yet,
and there are no binaries for download. These will be available
in a few days on http://www.psyco.org .

For the time being, please stick with subversion access,
building the extension module from source code. The repository
is here:

     http://codespeak.net/svn/psyco/v2/dist

Check-out the repository, and run the setup.py script,
given that you have access to a C compiler.

Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
and Mac OS X. Psyco is not supporting 64 bit, yet. But it
is well being considered.

The current improvements are, shortly:

   - Support for Python 2.4, 2.5 and 2.6
   - a lot of new builtins
   - generators, fast and fully supported.

More information is coming soon on http://www.psyco.org .

This is the beginning of a series of new Psyco versions.
Many more improvements are prepared and about to be published,
soon, starting with the current version 2.0.0 .

Stay tuned, this is just the beginning of psyco's re-birth!

For questions about Psyco V2, please join the mailing list

     psyco-devel at lists.sourceforge.net

or contact me on IRC:

     #psyco on irc.freenode.net .

Psyco V2 is fundamentally supported by FATTOC, LLC.
See http://www.fattoc.com .

Without their continuous support, this work would not have
been possible at all. I wish to express my deepest thanks
to FATTOC, for allowing me to continue on Psyco with all the
energy that this ambitious project needs, and will need.

Further special thanks are going to
Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
Raymond Hettinger, Fabrizio Milo, Michael Foord,
Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
for all the support and discussions.

Looking forward to a great future of Psyco!

July 17, 2009
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From ben+python at benfinney.id.au  Thu Jul 16 22:58:48 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 12:58:48 +1000
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
Message-ID: <87ljmogglz.fsf@benfinney.id.au>

Paul McGuire <ptmcg at austin.rr.com> writes:

> Two ideas come to mind, the decorator way and the metaclass way. I am
> not a guru at either, but these two examples work:

I think the decorator idea is most attractive to me, since it can be
applied per method.

> # the decorator way
> def inherit_docstring_from(cls):
>     def docstring_inheriting_decorator(fn):
>         fn.__doc__ = getattr(cls,fn.__name__).__doc__
>         return fn
>     return docstring_inheriting_decorator

That works, thank you.

> Using a decorator in this manner requires repeating the super class
> name.  Perhaps there is a way to get the bases of BarGonk, but I don't
> think so, because at the time that the decorator is called, BarGonk is
> not yet fully defined.

Yes, I tried a few different ways, but within the decorator it seems the
function object is quite unaware of what class it is destined for.

-- 
 \     ?We are human only to the extent that our ideas remain humane.? |
  `\                          ?_Breakfast of Champions_, Kurt Vonnegut |
_o__)                                                                  |
Ben Finney


From akhilanger at gmail.com  Thu Jul 16 23:26:39 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 20:26:39 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <pan.2009.07.17.01.21.48.641000@nowhere.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
Message-ID: <24528030.post@talk.nabble.com>


Well, you were write: unintentionally I removed strip(). But the problem does
not ends here:

I get this error now:

 File "./temp.py", line 488, in <module>
    main()
  File "./temp.py", line 475, in main
    for line in sys.stdin:
  File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
data

for this line:
?


--Akhil

Nobody-38 wrote:
> 
> On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:
> 
>>> In Python 3 you can't decode strings because they are Unicode strings
>>> and it doesn't make sense to decode a Unicode string. You can only
>>> decode encoded things which are byte strings. So you are mixing up byte
>>> strings and Unicode strings.
>>
>> Then, how should I do it?
>> I read a byte string from sys.stdin which needs to converted to unicode
>> string for further processing.
> 
> In 3.x, sys.stdin (stdout, stderr) are text streams, which means that they
> read and write Unicode strings, not byte strings.
> 
>> I cannot just remove the decode statement and
>> proceed?
>> 
>> This is it what it looks like:
>> 
>> for line in sys.stdin:
>>     line = line.decode('utf-8').strip()
>>     if line == '<page>': #do something here
>>     elsif #do something here
>>     
>> If I remove the decode statement, line == '<page>' never gets true. 
> 
> Did you inadvertently remove the strip() as well?
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24528030.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From aahz at pythoncraft.com  Thu Jul 16 23:39:39 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 20:39:39 -0700
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
	<h3nckg$db3$1@panix3.panix.com>
	<bfd28485-adaf-43ca-963d-3576c1c2cd4e@l2g2000vba.googlegroups.com>
Message-ID: <h3orpr$93l$1@panix3.panix.com>

In article <bfd28485-adaf-43ca-963d-3576c1c2cd4e at l2g2000vba.googlegroups.com>,
Tony  Lay  <tonylay at gmail.com> wrote:
>On Jul 16, 10:14=A0am, a... at pythoncraft.com (Aahz) wrote:
>> In article <45228cf4-0b37-4c52-bf6f-d7bd124b0... at l32g2000vbp.googlegroups=
>.com>,
>> Tony =A0Lay =A0<tony... at gmail.com> wrote:
>>>
>>>Traceback (most recent call last):
>>> =A0File "/usr/local/bin/meld", line 35, in <module>
>>> =A0 =A0import gettext
>>> =A0File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
>>> =A0 =A0import locale, copy, os, re, struct, sys
>>> =A0File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
>>> =A0 =A0import functools
>>> =A0File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
>>> =A0 =A0from _functools import partial, reduce
>>>ImportError: No module named _functools
>>
>> Where is _functools.so?
>
>/usr/local/lib/python2.6/lib-dynload/
>
>It's in the path...
>export PYTHONHOME=3D/usr/local/lib/python2.6
>export PYTHONPATH=3D/usr/local/lib/python2.6:/usr/local/lib/python2.6/
>site-packages:/usr/local/lib/python2.6/lib-dynload:/usr/local/etc/

What's in sys.path?  You might also get somewhere with "python -vv".
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From aurora00 at gmail.com  Thu Jul 16 23:55:11 2009
From: aurora00 at gmail.com (aurora00 at gmail.com)
Date: Thu, 16 Jul 2009 20:55:11 -0700 (PDT)
Subject: ctype performance benchmark
Message-ID: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>

I have done some performance benchmarking for Python's ctypes library.
I think you may find it interesting. I am planning to use ctypes as an
alternative to writing C extension module for performance enhancement.
Therefore my use case is slight different from the typical use case
for accessing existing third party C libraries. In this case I am both
the user and the implementer of the C library.

In order to determine what is the right granularity for context
switching between Python and C, I have done some benchmarking. I
mainly want to measure the function call overhead. So the test
functions are trivial function like returning the first character of a
string. I compare a pure Python function versus C module function
versus ctypes function. The tests are ran under Python 2.6 on Windows
XP with Intel 2.33Ghz Core Duo.

First of all I want to compare the function to get the first character
of a string. The most basic case is to reference it as the 0th element
of a sequence without calling any function. The produce the fastest
result at 0.0659 usec per loop.

  $ timeit "'abc'[0]"

  10000000 loops, best of 3: 0.0659 usec per loop

As soon as I build a function around it, the cost goes up
substantially. Both pure Python and C extension method shows similar
performance at around 0.5 usec. ctypes function takes about 2.5 times
as long at 1.37 usec.

  $ timeit -s "f=lambda s: s[0]"  "f('abc')"

  1000000 loops, best of 3: 0.506 usec per loop

  $ timeit -s "import mylib" "mylib.py_first('abc')"

  1000000 loops, best of 3: 0.545 usec per loop

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd')"
              "dll.first('abc')"

  1000000 loops, best of 3: 1.37 usec per loop

I repeated the test with a long string (1MB). There are not much
difference in performance. So I can be quite confident that the
parameter is passed by reference (of the internal buffer).

  $ timeit -s "f=lambda s: s[0]; lstr='abcde'*200000"
              "f(lstr)"

  1000000 loops, best of 3: 0.465 usec per loop

  $ timeit -s "import mylib; lstr='abcde'*200000"
              "mylib.py_first(lstr)"

  1000000 loops, best of 3: 0.539 usec per loop

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd')"
           -s "lstr='abcde'*200000"
              "dll.first(lstr)"

  1000000 loops, best of 3: 1.4 usec per loop

Next I have make some attempts to speed up ctypes performance. A
measurable improvement can be attained by eliminating the attribute
look up for the function. Curiously this shows no improvement in the
similar case for C extension.

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd');
           -s "f=dll.first"
              "f('abcde')"

  1000000 loops, best of 3: 1.18 usec per loop

Secondary I have tried to specify the ctypes function prototype. This
actually decrease the performance significantly.

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd')"
           -s "f=dll.first"
           -s "f.argtypes=[ctypes.c_char_p]"
           -s "f.restype=ctypes.c_int"
              "f('abcde')"

  1000000 loops, best of 3: 1.57 usec per loop

Finally I have tested passing multiple parameters into the function.
One of the parameter is passed by reference in order to return a
value. Performance decrease as the number of parameter increase.

  $ timeit -s "charAt = lambda s, size, pos: s[pos]"
           -s "s='this is a test'"
              "charAt(s, len(s), 1)"

  1000000 loops, best of 3: 0.758 usec per loop

  $ timeit -s "import mylib; s='this is a test'"
              "mylib.py_charAt(s, len(s), 1)"

  1000000 loops, best of 3: 0.929 usec per loop

  $ timeit -s "import ctypes"
           -s "dll = ctypes.CDLL('mylib.pyd')"
           -s "s='this is a test'"
           -s "ch = ctypes.c_char()"
              "dll.charAt(s, len(s), 1, ctypes.byref(ch))"

  100000 loops, best of 3: 2.5 usec per loop

One style of coding that improve the performance somewhat is to build
a C struct to hold all the parameters.

  $ timeit -s "from test_mylib import dll, charAt_param"
           -s "s='this is a test'"
           -s "obj = charAt_param(s=s, size=len(s), pos=3, ch='')"
              "dll.charAt_struct(obj)"

  1000000 loops, best of 3: 1.71 usec per loop

This may work because most of the fields in the charAt_param struct
are invariant in the loop. Having them in the same struct object save
them from getting rebuilt each time.

My overall observation is that ctypes function has an overhead that is
2 to 3 times to a similar C extension function. This may become a
limiting factor if the function calls are fine grained. Using ctypes
for performance enhancement is a lot more productive if the interface
can be made to medium or coarse grained.

A snapshot of the source code used for testing is available for
download

  http://tungwaiyip.info/blog/2009/07/16/ctype_performance_benchmark

Wai Yip Tung


From aurora00 at gmail.com  Fri Jul 17 00:03:14 2009
From: aurora00 at gmail.com (Wai Yip)
Date: Thu, 16 Jul 2009 21:03:14 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <f9e8a620-40ee-4981-82ea-29184f9ef2b1@f20g2000prn.googlegroups.com>

I think Diez' example show this work automatically in Unix. In my case
I use Windows. I use the multiprocessing.Array to share data in shared
memory. multiprocessing.Array has a limitation that it can only
reference simple C data types, not Python objects though.

Wai Yip Tung


From crazypangolin at gmail.com  Fri Jul 17 00:44:26 2009
From: crazypangolin at gmail.com (aj)
Date: Thu, 16 Jul 2009 21:44:26 -0700 (PDT)
Subject: error when compiling source on linux
Message-ID: <1c8d7530-873b-4f52-8d0f-21a6b79de339@p9g2000vbl.googlegroups.com>

when I try to compile Python 2.6 from source code on ubuntu, I get the
message
/usr/bin/ld: cannot open output file python: Is a directory
collect2: ld returned 1 exit status
make: *** [python] Error 1
PLEASE HELP!


From aahz at pythoncraft.com  Fri Jul 17 01:08:31 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 22:08:31 -0700
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
Message-ID: <h3p10f$164$1@panix3.panix.com>

In article <mailman.3221.1247757153.8015.python-list at python.org>,
Gabriel Rossetti  <gabriel.rossetti at arimaz.com> wrote:
>
>I am using threading.Condition.wait(timeout) and was surprised to see 
>that there is no return value nor an exception when wait() is used w/ a 
>timeout. How am I supposed to know if it was notified or if it timed out?

What are you trying to do?  Maybe your purpose would be better suited to
using a Queue?  (Yes, Queue is a hammer in search of a nail, but most
threading problems are easier if you treat them as nails.)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From alan.isaac at gmail.com  Fri Jul 17 01:19:50 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 17 Jul 2009 05:19:50 GMT
Subject: invoke method on many instances
Message-ID: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>

As a recurrent situation, I need to invoke the same method
on many instances.  Speed matters, but the solution should
be pure Python.  Is the following convenience function
a reasonable approach?

def apply2(itr, methodname, *args, **kwargs):
    f = operator.methodcaller(methodname, *args, **kwargs)
    for item in itr:
        f(item)

(Comment: in the case at hand, the methods return None.)

Thank you,
Alan Isaac




From contact at xavierho.com  Fri Jul 17 01:31:28 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 13:31:28 +0800
Subject: Try... except....Try again?
Message-ID: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>

I have a simple class that generates prime numbers, using memorisation and
iteration to generate the next prime number.

In the class, I have defined a function that gives, say, the 5th prime
number. Or the 1000th, it's still very fast. But the code isn't what I
really like.

    def nPrime(self, n):
        "Returns nth prime number, the first one being 2, where n = 0. When
n = 1, it returns 3."
        while True:
            try:
                return self.primes[n]
            except:
                self.next()

The next() function generates the next prime, and appends it into primes.
This way, it keeps trying to append until the nth prime requested exist, and
returns it.

My problem is that it's a "While True" loop, which I get a lot of "Don't do
it!" In the light of making the code better, what could I do?

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/3fb273f6/attachment.html>

From gabriel.rossetti at arimaz.com  Fri Jul 17 02:12:38 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 17 Jul 2009 08:12:38 +0200
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <26ddd1750907161422n5b640a48pbbf9325dd05a699d@mail.gmail.com>
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>
	<26ddd1750907161422n5b640a48pbbf9325dd05a699d@mail.gmail.com>
Message-ID: <4A601656.1070802@arimaz.com>

Maxim Khitrov wrote:
> On Thu, Jul 16, 2009 at 5:00 PM, Carl Banks<pavlovevidence at gmail.com> wrote:
>   
>> On Jul 16, 8:12 am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
>> wrote:
>>     
>>> Hello everyone,
>>>
>>> I am using threading.Condition.wait(timeout) and was surprised to see
>>> that there is no return value nor an exception when wait() is used w/ a
>>> timeout. How am I supposed to know if it was notified or if it timed out?
>>>       
>> That's a good question.  Condition.wait seems to violate an invariant
>> if it can return without having acquired the underlying lock.  And if
>> it does the least it could do is to return a status so you know if you
>> have to skeddadle.
>>
>> Workaround is to use the _is_owned() method of Condition to see if you
>> are the owner of the condition, but this method is undocumented.
>>
>> cond = Condition()
>> ...
>> cond.acquire()
>> while not ok_to_proceed():
>>    cond.wait()
>>    if not cond._is_owned():
>>        # must've timed out
>>        raise TimeOutException
>> operate()
>> cond.release()
>>     
>
> You will always be the owner of the condition whether it times out or
> your thread is notified. This doesn't solve the problem. As an aside,
> the implementation of wait() is rather poor in any case; the sleep
> function should not be used for the purpose of waiting for an event.
>
> Depending on what platform you are using, I can offer two solutions.
> The simplest one is to subclass Condition and override the wait
> method. Just copy the code as it is, but modify the end of the
> function to look like this:
>
>                 if not gotit:
>                     if __debug__:
>                         self._note("%s.wait(%s): timed out", self, timeout)
>                     try:
>                         self.__waiters.remove(waiter)
>                     except ValueError:
>                         pass
>                     return False
>                 else:
>                     if __debug__:
>                         self._note("%s.wait(%s): got it", self, timeout)
>                     return True
>
> The two return statements will tell you whether you timed out ("if not
> gotit" condition), or were notified ("else").
>
> The better way to solve this and the other problem that I mentioned is
> to use native OS events. This is what I had to do for a recent
> project. I used pywin32 extension to completely rewrite Event,
> Condition, and Timer classes to use a true event-based approach. In
> the process of the rewrite I also modified some functionality, such as
> returning True of False from wait().
>
> Unfortunately, I'm not able to post this code right now, though I can
> try and get permission to do so a bit later. If you are writing
> software for Windows, then simply take a look at win32event module.
> CreateEvent, SetEvent, ResetEvent, WaitForSingleObject are all the
> Windows functions that you need to reimplement threading.Event. Using
> the new event class you can implement a proper Condition.wait() method
> (hint: use new events rather than locks to wait for notification).
>
> If you are on Linux or BSD, I can't help you. I'm sure that there is
> some equivalent functionality that you may be able to access using
> ctypes. Exactly how to do it, however, is not something that I can
> help you with right now.
>
> - Max
>   

Thank you, I will try that. I am coding for Linux, Mac & Windows (and 
any POSIX platform, but right now I support only those three).

Gabriel


From koranthala at gmail.com  Fri Jul 17 02:13:51 2009
From: koranthala at gmail.com (koranthala)
Date: Thu, 16 Jul 2009 23:13:51 -0700 (PDT)
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com> 
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com> 
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl> 
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
Message-ID: <10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>

> That test was designed to treat None as a boolean False, without
> noticing that numeric 0 is also treated as False and could make the
> test do the wrong thing.  This is an extremely common type of error.

Actually, I felt that 0 not being considered False would be a better
option.
I had lot of instances where 0 is a valid value and always I had to
put checks specifically for that.
For me, None and False should be equal to False in if checks, every
thing else being considered True.

Can someone let me know why 0 is considered equal to False?
There should be real good reasons for it, only that I cannot think of
one.


From gabriel.rossetti at arimaz.com  Fri Jul 17 02:25:23 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 17 Jul 2009 08:25:23 +0200
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <m21voguvxz.fsf@cs.uu.nl>
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
Message-ID: <4A601953.5000603@arimaz.com>

Piet van Oostrum wrote:
>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>             
>
>   
>> GR> Hello everyone,
>> GR> I am using threading.Condition.wait(timeout) and was surprised to see that
>> GR> there is no return value nor an exception when wait() is used w/ a timeout.
>> GR> How am I supposed to know if it was notified or if it timed out?
>>     
>
> Normally you wouldn't have to know. The logic of your program should be
> such that you wait until a certain condition is satisfied. After each
> wait you usually check that condition anyway, like:
>
> while (some_condition_satisfied):
>     cond_var.wait()
>
> The only exception could be if there is a 1-1 relation between a single
> waiter and a single notifier. I that case you can usually use if instead
> of while (but it does depend of the logic of the notifier).
>   

I have a 1-1 relation, I have a thread reading msgs from a network 
socket and a method waiting for an answer to arrive (see my thread 
"Threading.Condition problem"). I would like to be able to have a 
timeout as to not block forever, so the idea is to check if I returned 
because of a timeout or not.

> So in case of using a timeout you can check the desired condition after
> the wait and decide what to do. If the condition was not satisfied you
> probably want to do something special, like error handling, or do
> something else first and then retry the wait.
>
> There could be situations where this doesn't work, however. For example
> if you wait until a queue is not empty, and the notify is done when
> something is inserted in the queue, another thread may sneak in while
> you are waiting and snatch the inserted item just before your thread
> continues after the wait. In that case you can't distinguish between a
> timeout and a snatcher.
>
> So it all depends on what your use case is.
>
> (Java's wait doesn't return anything either.)
>   


From __peter__ at web.de  Fri Jul 17 02:28:46 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 17 Jul 2009 08:28:46 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com> <h3obqg$aru$1@ger.gmane.org>
	<mailman.3246.1247792169.8015.python-list@python.org>
Message-ID: <h3p5mm$o6s$01$1@news.t-online.com>

Terry Reedy wrote:

> Terry Reedy wrote:
> 
>>> $ file tmp.ps
>>> tmp.ps: PostScript document text conforming DSC level 3.0, type EPS
>>>
>>> Try changing the file extension from .ps to .eps.
>> 
>> I will. Thank you.
> 
> I tried it. Unfortunately, OOo does not open it correctly. It just
> displays the first three lines of metadate - Title, Creator, Date -- as
> image text. Photoshop does read the image, and does an ok job of
> conversion once anti-aliasing is turned off.

I snatched some code from the module and modified it to save a sample image:

from turtle import *

def switchpen():
    if isdown():
        pu()
    else:
        pd()

def demo2():
    """Demo of some new features."""
    speed(1)
    st()
    pensize(3)
    setheading(towards(0, 0))
    radius = distance(0, 0)/2.0
    rt(90)
    for _ in range(18):
        switchpen()
        circle(radius, 10)
    write("wait a moment...")
    while undobufferentries():
        undo()
    reset()
    lt(90)
    colormode(255)
    laenge = 10
    pencolor("green")
    pensize(3)
    lt(180)
    for i in range(-2, 16):
        if i > 0:
            begin_fill()
            fillcolor(255-15*i, 0, 15*i)
        for _ in range(3):
            fd(laenge)
            lt(120)
        laenge += 10
        lt(15)
        speed((speed()+1)%12)
    end_fill()

    lt(120)
    pu()
    fd(70)
    rt(30)
    pd()
    color("red","yellow")
    speed(0)
    fill(1)
    for _ in range(4):
        circle(50, 90)
        rt(90)
        fd(30)
        rt(90)
    fill(0)
    lt(90)
    pu()
    fd(30)
    pd()
    shape("turtle")

    tri = getturtle()
    tri.resizemode("auto")
    turtle = Turtle()
    turtle.resizemode("auto")
    turtle.shape("turtle")
    turtle.reset()
    turtle.left(90)
    turtle.speed(0)
    turtle.up()
    turtle.goto(280, 40)
    turtle.lt(30)
    turtle.down()
    turtle.speed(6)
    turtle.color("blue","orange")
    turtle.pensize(2)
    tri.speed(6)
    setheading(towards(turtle))
    count = 1
    while tri.distance(turtle) > 4:
        turtle.fd(3.5)
        turtle.lt(0.6)
        tri.setheading(tri.towards(turtle))
        tri.fd(4)
        if count % 20 == 0:
            turtle.stamp()
            tri.stamp()
            switchpen()
        count += 1
    tri.write("CAUGHT! ", font=("Arial", 16, "bold"), align="right")

if __name__ == "__main__":
    demo2()
    Screen().getcanvas().postscript(file="demo2.eps")

I could successfully insert the picture into Writer.

I'm on Kubuntu 9.04 with Python 2.6.2 and OpenOffice 3.0.1.
 
> Hmmm. Crazy idea... in
> 
http://us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-
PyCon2007.pdf
> Gregor Lingl says that turtle.py has been ported to pygame and jython as
> back ends. It should be possible to instead send output to a file
> instead of an on-screen canvas. Run a program to screen. When output
> looks right, return with a different parameter to send to file.
> 
> For instance, an OpenDocumentDrawing file (.odd) using odfpy.
> This assumes that there are elements corresponding to each turtle
> command. Or at least that the fit is close enough.

I can see nothing crazy about that.

But still, turtle is an educational tool, its main advantage is that it can 
show beginners how the image is generated.

If you want to generate high-quality graphics easily you need different 
primitives.

http://cairographics.org

has Python bindings, but I don't know if it's available on Windows.

Peter



From clp2 at rebertia.com  Fri Jul 17 02:30:39 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 23:30:39 -0700
Subject: Einstein summation notation (was: question of style)
In-Reply-To: <10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <50697b2c0907162330m60327179j6f7fcf0427beac3c@mail.gmail.com>

On Thu, Jul 16, 2009 at 11:13 PM, koranthala<koranthala at gmail.com> wrote:
>> That test was designed to treat None as a boolean False, without
>> noticing that numeric 0 is also treated as False and could make the
>> test do the wrong thing. ?This is an extremely common type of error.
>
> Actually, I felt that 0 not being considered False would be a better
> option.
> I had lot of instances where 0 is a valid value and always I had to
> put checks specifically for that.
> For me, None and False should be equal to False in if checks, every
> thing else being considered True.
>
> Can someone let me know why 0 is considered equal to False?
> There should be real good reasons for it, only that I cannot think of
> one.

* Because that's how C does/did it (primary motivation)
- Because if Boolean algebra is implemented using numbers, False is 0
- Because philosophically, 0 is the "empty" or null value for numbers,
        and empty values are by convention considered false in Python
- Because it's the behavior people want 75% of the time.

FWIW, your paradigm of true/false is used by Lisp and Lisp wannabes
such as Ruby.

Cheers,
Chris
-- 
http://blog.rebertia.com


From __peter__ at web.de  Fri Jul 17 02:58:40 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 17 Jul 2009 08:58:40 +0200
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <h3p7en$n4f$02$1@news.t-online.com>

Ben Finney wrote:

> Howdy all,
> 
> The following is a common idiom::
> 
>     class FooGonk(object):
>         def frobnicate(self):
>             """ Frobnicate this gonk. """
>             basic_implementation(self.wobble)
> 
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
> 
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
> 
> Ideally there would be a way to specify that the docstring should be
> inherited. The best I can come up with is::
> 
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>         frobnicate.__doc__ = FooGonk.frobnicate.__doc__
> 
> but that violates DRY (the association between BarGonk and FooGonk is
> being repeated), puts the docstring assignment awkwardly after the end
> of the method instead of at the beginning where docstrings normally go,
> and reads poorly besides.
> 
> What is the most Pythonic, DRY-adherent, and preferably least-ugly
> approach to override a method, but have the same docstring on both
> methods?

Just thinking aloud: Write a patch for pydoc that looks up the base-class 
documentation.

B.f.__doc__ will continue to return None, but

help(B.f) will show something like

    No documentation available for B.f. 

    Help for A.f:
    yadda yadda


Of course that might be misleading when A.f and B.f are up to something 
completely different...

Peter



From nobody at nowhere.com  Fri Jul 17 03:20:15 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 17 Jul 2009 08:20:15 +0100
Subject: UnicodeEncodeError: 'ascii' codec can't encode character	u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<mailman.3258.1247801202.8015.python-list@python.org>
Message-ID: <pan.2009.07.17.07.20.15.547000@nowhere.com>

On Thu, 16 Jul 2009 20:26:39 -0700, akhil1988 wrote:

> Well, you were write: unintentionally I removed strip(). But the problem does
> not ends here:
> 
> I get this error now:
> 
>  File "./temp.py", line 488, in <module>
>     main()
>   File "./temp.py", line 475, in main
>     for line in sys.stdin:
>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>     (result, consumed) = self._buffer_decode(data, self.errors, final)
> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
> data
> 
> for this line:
> ?

Right. You're running in a locale whose encoding is UTF-8, but feeding
data which isn't valid UTF-8 to stdin. If you want to use data with a
different encoding, you need to replace sys.stdin, e.g.:

import sys
import io
sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding = 'iso-8859-1')



From Lacrima.Maxim at gmail.com  Fri Jul 17 03:24:48 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Fri, 17 Jul 2009 00:24:48 -0700 (PDT)
Subject: urllib with x509 certs
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<4a4f2307$0$8384$9b622d9e@news.freenet.de>
	<a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>
	<4A4F387F.7050804@v.loewis.de>
Message-ID: <c2a05022-0ae2-4518-8e8d-2a29921db8a4@s31g2000yqs.googlegroups.com>

Hello!

I've solved this problem, using pyCurl.
Here is sample code.

import pycurl
import StringIO
b = StringIO.StringIO()
c = pycurl.Curl()
url = 'https://example.com/'
c.setopt(pycurl.URL, url)
c.setopt(pycurl.WRITEFUNCTION, b.write)
c.setopt(pycurl.CAINFO, 'cert.crt')
c.setopt(pycurl.SSLKEY, 'mykey.key')
c.setopt(pycurl.SSLCERT, 'mycert.cer')
c.setopt(pycurl.SSLKEYPASSWD , 'pass phrase')
c.perform()

This also allow to specify CA, so your requests are more secure then
with urllib.

With regards, Max.


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:28:32 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:28:32 GMT
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <02701951$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 23:13:51 -0700, koranthala wrote:

>> That test was designed to treat None as a boolean False, without
>> noticing that numeric 0 is also treated as False and could make the
>> test do the wrong thing.  This is an extremely common type of error.
> 
> Actually, I felt that 0 not being considered False would be a better
> option.
> I had lot of instances where 0 is a valid value and always I had to put
> checks specifically for that.
> For me, None and False should be equal to False in if checks, every
> thing else being considered True.

I believe it would be a mistake for None == False to return True.

As far as having only None and False to be considered equivalent in truth 
contexts, that's awfully limiting. It is very useful to be able to write 
e.g.:

if header or body or footer:
    print assemble_page(header, body, footer)

and have empty strings to be equivalent to False.


Lisp and (I think) Ruby behaves as you want. Python doesn't. We think 
it's Lisp and Ruby that got it wrong :)


> Can someone let me know why 0 is considered equal to False? There should
> be real good reasons for it, only that I cannot think of one.

Having 0 considered false goes back to branching in machine language, 
which I understand are typically. The Null value (e.g. nil in Pascal, nul 
in C) are usually implemented as pointer values equal to an address of 
zero.

It essentially boils down to this: the behaviour of if...else is a 
convention. The language designer might choose to have an explicit 
Boolean type, and prohibit "if None" (e.g. Pascal does this). It might 
choose to treat flags as integers, and branch according to the integer 
being zero (false) or non-zero (true) (e.g. Forth does this). Python 
allows any object to be tested by if, and branches according to whether 
it is Something or Nothing. It's a logical dichotomy, and treating 0 and 
[] as Something instead of Nothing would make it arbitrary and strange.



-- 
Steven


From http  Fri Jul 17 03:34:00 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 00:34:00 -0700
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <7xljmnahlj.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> It is very useful to be able to write e.g.:
> if header or body or footer:
>     print assemble_page(header, body, footer)
> and have empty strings to be equivalent to False.

Why doesn't assemble_page properly handle the case where header, body,
and footer are all empty?  That would let you eliminate the if.  "Make
sure your code 'does nothing' gracefully" (Kernighan and Plauger).


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:45:08 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:45:08 GMT
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
Message-ID: <02701d35$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:

> As a recurrent situation, I need to invoke the same method on many
> instances.  Speed matters, but the solution should be pure Python.  Is
> the following convenience function a reasonable approach?
>
> def apply2(itr, methodname, *args, **kwargs):
>     f = operator.methodcaller(methodname, *args, **kwargs)
>     for item in itr:
>         f(item)

I don't particularly like your naming conventions, but never mind.

You could also try this:

for obj in objects:
    getattr(obj, methodname)(*args, **kwargs)




See also these recipes from the "Python Cookbook":

http://code.activestate.com/recipes/52289/
http://code.activestate.com/recipes/87370/




-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:52:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:52:19 GMT
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
	<87ljmogglz.fsf@benfinney.id.au>
Message-ID: <02701ee5$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 12:58:48 +1000, Ben Finney wrote:

>> Using a decorator in this manner requires repeating the super class
>> name.  Perhaps there is a way to get the bases of BarGonk, but I don't
>> think so, because at the time that the decorator is called, BarGonk is
>> not yet fully defined.
> 
> Yes, I tried a few different ways, but within the decorator it seems the
> function object is quite unaware of what class it is destined for.


When the decorator is called, the function object is just a function 
object, not a method, so there is no concept of "what class it is 
destined for".

>>> def dec(func):
...     print type(func)
...     try:
...             print func.im_class
...     except:
...             print "no im_class"
...     return func
...
>>> class Test(object):
...     @dec
...     def spam(self):
...             pass
...
<type 'function'>
no im_class
>>> type(Test.spam)
<type 'instancemethod'>
>>> Test.spam.im_class
<class '__main__.Test'>


I suppose you could try to determine what namespace you're currently when 
the class is created, but that's surely going to be fragile and messy.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:56:07 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:56:07 GMT
Subject: TypeError: unbound method
References: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>
	<mailman.3248.1247792929.8015.python-list@python.org>
Message-ID: <02701fc9$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 18:08:45 -0700, Chris Rebert wrote:

> You're trying to call an instance method on the class itself, which
> doesn't make sense.

Oh I don't know, people do it all the time -- just not the way the OP 
did :)

> You need to first create an instance of the class to invoke the method
> on. i.e.:
> 
> instance = TheClass(constuctor_arguments_here)
> var1 = instance.method()

Or explicitly pass an instance to the method when calling from the class:

TheClass.method(TheClass(constuctor_arguments_here))


Which strangely enough, is useful at times.

class K(parent):
    def method(self, args):
        x = parent.method(self, args)
        return x + 1



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 04:06:22 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 08:06:22 GMT
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>
	<mailman.3224.1247760199.8015.python-list@python.org>
Message-ID: <0270222f$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 11:02:57 -0500, Pablo Torres N. wrote:

> On Thu, Jul 9, 2009 at 22:07, Steven
> D'Aprano<steven at remove.this.cybersource.com.au> wrote:
>> On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:
>>
>>> def list_items_in_string(list_items, string):
>>> ? ? for item in list_items:
>>> ? ? ? ? if item in string:
>>> ? ? ? ? ? ? return True
>>> ? ? return False
>> ...
>>> Any ideas how to make that function look nicer? :)
>>
>> Change the names. Reverse the order of the arguments. Add a docstring.
>>
>>
> Why reverse the order of the arguments? Is there a design principle
> there?

It's just a convention. Before strings had methods, you used the string 
module, e.g.:

string.find(source, target)
=> find target in source

This became source.find(target).

In your function:

list_items_in_string(list_items, string)

"list_items" is equivalent to target, and "string" is equivalent to 
source. It's conventional to write the source first.



-- 
Steven


From piet at cs.uu.nl  Fri Jul 17 04:12:52 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:12:52 +0200
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <m2my73u3qz.fsf_-_@cs.uu.nl>

>>>>> koranthala <koranthala at gmail.com> (k) wrote:

>>> That test was designed to treat None as a boolean False, without
>>> noticing that numeric 0 is also treated as False and could make the
>>> test do the wrong thing.  This is an extremely common type of error.

>k> Actually, I felt that 0 not being considered False would be a better
>k> option.
>k> I had lot of instances where 0 is a valid value and always I had to
>k> put checks specifically for that.
>k> For me, None and False should be equal to False in if checks, every
>k> thing else being considered True.

>k> Can someone let me know why 0 is considered equal to False?
>k> There should be real good reasons for it, only that I cannot think of
>k> one.

Originally Python didn't have booleans. Integers were used instead (but
not exclusively). 0 was False, everything else True (with a slight
preference for 1 as True). Same as in C. Nowadays this is reflected in
bool being a subtype of int with False == 0 and True == 1. Actually it
is even closer: False and True are just 0 and 1 cast to bool, so to say.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From oisin.mulvihill at gmail.com  Fri Jul 17 04:14:45 2009
From: oisin.mulvihill at gmail.com (Oisin Mulvihill)
Date: Fri, 17 Jul 2009 09:14:45 +0100
Subject: ann: servicestation - run your linux/mac services on windows without
	needing pywin...
Message-ID: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>

Hi There,

I gave a lightning talk about my ServiceStation project at Europython  
2009. While it
isn't written in Python (C++/Windows), I did write it with python in  
mind. Its
released under the CDDL license.

I'm hoping it will be of use to other Python users who will need to  
run their services
on windows, but don't want to learn much/anything about windows  
service programming.

The ServiceStation blurb is:

   ServiceStation allows you to run arbitrary programs as a
   service on the Windows platform. The program you wish to
   run does not need to be changed to allow it to work with
   ServiceStation or windows services.

   This project was developed with an eye to running Python web
   services on Windows, without the need to use and include Pywin32.
   This meant we could take services running on Linux/Mac and
   run them unmodified on Windows."

If your interested in this check out the projects trac page for docs  
and download

   http://www.foldingsoftware.com/servicestation

All the best,

Oisin



From piet at cs.uu.nl  Fri Jul 17 04:26:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:26:27 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <m2iqhru34c.fsf@cs.uu.nl>

There is stil something not clear in your description.

>m> I'm using multiprocessing to spawn several subprocesses, each of which
>m> uses a very large data structure (making it impractical to pass it via
>m> pipes / pickling). I need to allocate this structure once when the
>m> process is created and have it remain in memory for the duration of
>m> the process. 

I have read this as that every subprocess has its own large
data structure and that there is no connection between these.

But seeing where the discussion is going I guess there might be
different interpretations. So can you enlighten us how the situation is?

1. Each subprocess has a copy of a data structure that is prepared by the
   master process. Therefore you want it to be passed by the fork
   1a. the data structure is constant i.e. the subprocess doesn't change it
   1b. the subprocess makes changes in its copy
2. Each subprocess has a seperate data structure not equal to the others
3. Something else.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mail at timgolden.me.uk  Fri Jul 17 04:34:27 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 17 Jul 2009 09:34:27 +0100
Subject: ann: servicestation - run your linux/mac services on windows
	without	needing pywin...
In-Reply-To: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>
References: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>
Message-ID: <4A603793.3070803@timgolden.me.uk>

Oisin Mulvihill wrote:
> Hi There,
> 
> I gave a lightning talk about my ServiceStation project at Europython 
> 2009. While it
> isn't written in Python (C++/Windows), I did write it with python in 
> mind. Its
> released under the CDDL license.
> 
> I'm hoping it will be of use to other Python users who will need to run 
> their services
> on windows, but don't want to learn much/anything about windows service 
> programming.

> If your interested in this check out the projects trac page for docs and download
>   http://www.foldingsoftware.com/servicestation 

It's not clear at a glance how this differs from, say, the
venerable SRVANY.EXE and a slew of other "Run-things-as-a-service"
programs. Absolutely not wishing to be disparaging, but what
is servicestation offering to distinguish itself?

TJG


From stefan_ml at behnel.de  Fri Jul 17 04:35:54 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Fri, 17 Jul 2009 10:35:54 +0200
Subject: ctype performance benchmark
In-Reply-To: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
Message-ID: <4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>

aurora00 at gmail.com wrote:
> My overall observation is that ctypes function has an overhead that is
> 2 to 3 times to a similar C extension function. This may become a
> limiting factor if the function calls are fine grained. Using ctypes
> for performance enhancement is a lot more productive if the interface
> can be made to medium or coarse grained.

I think ctypes is ok for its niche: easy interfacing with C stuff from
straight Python code, without further dependencies. There will always (and
necessarily) be a call overhead involved. Anyone who needs to care about
per-call performance would use something else anyway (do I need to mention
Cython here?)

Stefan


From piet at cs.uu.nl  Fri Jul 17 04:37:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:37:27 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
	<mailman.3261.1247811927.8015.python-list@python.org>
Message-ID: <m2eisfu2m0.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> I have a 1-1 relation, I have a thread reading msgs from a network socket
>GR> and a method waiting for an answer to arrive (see my thread
>GR> "Threading.Condition problem"). I would like to be able to have a timeout
>GR> as to not block forever, so the idea is to check if I returned because of a
>GR> timeout or not.

So that case is easy I think. After the wait just check if the answer
has arrived.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Fri Jul 17 04:47:36 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:47:36 +0200
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<mailman.3258.1247801202.8015.python-list@python.org>
Message-ID: <m27hy7u253.fsf@cs.uu.nl>

>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:

>a> Well, you were write: unintentionally I removed strip(). But the problem does
>a> not ends here:

>a> I get this error now:

>a>  File "./temp.py", line 488, in <module>
>a>     main()
>a>   File "./temp.py", line 475, in main
>a>     for line in sys.stdin:
>a>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>a>     (result, consumed) = self._buffer_decode(data, self.errors, final)
>a> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
>a> data

>a> for this line:
>a> ?

Your Python assumes stdin uses utf-8 encoding, probably because your
locale says so. But it seems the input is not really utf-8 but some
other encoding.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From oisin.mulvihill at gmail.com  Fri Jul 17 05:13:49 2009
From: oisin.mulvihill at gmail.com (Oisin Mulvihill)
Date: Fri, 17 Jul 2009 02:13:49 -0700 (PDT)
Subject: ann: servicestation - run your linux/mac services on windows 
	without needing pywin...
References: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com> 
	<mailman.3264.1247819628.8015.python-list@python.org>
Message-ID: <42b910db-7e71-4f26-81ed-ee6a2f29ca56@26g2000yqk.googlegroups.com>

On Jul 17, 9:34?am, Tim Golden <m... at timgolden.me.uk> wrote:
> Oisin Mulvihill wrote:
> > Hi There,
>
> > I gave a lightning talk about my ServiceStation project at Europython
> > 2009. While it
> > isn't written in Python (C++/Windows), I did write it with python in
> > mind. Its
> > released under the CDDL license.
>
> > I'm hoping it will be of use to other Python users who will need to run
> > their services
> > on windows, but don't want to learn much/anything about windows service
> > programming.
> > If your interested in this check out the projects trac page for docs and download
> > ?http://www.foldingsoftware.com/servicestation
>
> It's not clear at a glance how this differs from, say, the
> venerable SRVANY.EXE and a slew of other "Run-things-as-a-service"
> programs. Absolutely not wishing to be disparaging, but what
> is servicestation offering to distinguish itself?
>
> TJG

Hi There,

I have to admit I didn't come across srvany before. I may not have
used the right google fu the day I decided to do this ;) So maybe it
does all the following, however servicestation distingusihes itself
by:

 * Properly tracking all child processes launched by the command it
runs and closes them on stop/restart.

 * Monitoring the command its running and keeping it alive.

 * Allows you to set the description / name from the config file.

 * It logs useful information to the event viewer so you can see why
it couldn't run the command under its care.

 * Can interact with the desktop or not so you can run programs with a
gui but not actually see it.

 * Does not disconnect the service if you log-out as some runners do.

Thats all I can think of. I should probably add this to this wiki too,

Thanks for prompting me on this.

Oisin




From peter.fodrek at stuba.sk  Fri Jul 17 05:24:59 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Fri, 17 Jul 2009 11:24:59 +0200
Subject: error when compiling source on linux
In-Reply-To: <1c8d7530-873b-4f52-8d0f-21a6b79de339@p9g2000vbl.googlegroups.com>
References: <1c8d7530-873b-4f52-8d0f-21a6b79de339@p9g2000vbl.googlegroups.com>
Message-ID: <200907171124.59610.peter.fodrek@stuba.sk>

On Friday 17 July 2009 06:44:26 aj wrote:
> when I try to compile Python 2.6 from source code on ubuntu, I get the
> message
> /usr/bin/ld: cannot open output file python: Is a directory

This says that there is directory in the sources with same name as will be 
named output

It can only occur when you are not compiling software correctly via INSTALL or 
README file

I think you made 

./configure
make

as compiling process

if this is true try 

mkdir bulid
cd build
../configure
make
make install


Kind regards 

Peter 


From mail at timgolden.me.uk  Fri Jul 17 05:26:09 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 17 Jul 2009 10:26:09 +0100
Subject: ann: servicestation - run your linux/mac services on windows
	without needing pywin...
In-Reply-To: <42b910db-7e71-4f26-81ed-ee6a2f29ca56@26g2000yqk.googlegroups.com>
References: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>
	<mailman.3264.1247819628.8015.python-list@python.org>
	<42b910db-7e71-4f26-81ed-ee6a2f29ca56@26g2000yqk.googlegroups.com>
Message-ID: <4A6043B1.8010500@timgolden.me.uk>

Oisin Mulvihill wrote:
> I have to admit I didn't come across srvany before. 

It's been part of the Windows Resource Kit since way back,
but like many such things is probably known more by word-of-mouth
than by Internet Searchability

>  * Properly tracking all child processes launched by the command it
> runs and closes them on stop/restart.
> 
>  * Monitoring the command its running and keeping it alive.
> 
>  * Allows you to set the description / name from the config file.
> 
>  * It logs useful information to the event viewer so you can see why
> it couldn't run the command under its care.
> 
>  * Can interact with the desktop or not so you can run programs with a
> gui but not actually see it.
> 
>  * Does not disconnect the service if you log-out as some runners do.

Looks very interesting. Definitely put this on the front page,
otherwise people may think as I did that this is just another
srvany clone. 

TJG


From hartley79 at gmail.com  Fri Jul 17 05:59:46 2009
From: hartley79 at gmail.com (hartley)
Date: Fri, 17 Jul 2009 02:59:46 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com> 
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com> 
	<h3nusa$pcb$1@panix3.panix.com>
Message-ID: <94c1adf3-a25d-4ae5-9f38-7ca8680d022d@b14g2000yqd.googlegroups.com>

On Jul 16, 9:26?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <0afc5c4d-1af5-4d0e-9442-26b51b12e... at m11g2000yqh.googlegroups.com>,
>
> hartley ?<hartle... at gmail.com> wrote:
>
> >If you had loosened up on the sarcasm I would probably have read what
> >you wrote more thoroughly instead of just skimming through it. Thanks
> >for the help, but you should seriously consider doing something with
> >your patronizing attitude.
>
> http://www.mikeash.com/getting_answers.htmlhttp://www.catb.org/~esr/faqs/smart-questions.html

>From "http://www.mikeash.com/getting_answers.html":

How To Ask Questions The Smart Way is pretty condescending, especially
if you already feel insulted by somebody telling you that you need
help asking questions. If you're pointed at a guide with a filename of
smart-questions, that means this person thinks you have stupid
questions, and who needs that?

Cheers mate :)

-Hartley


From ben+python at benfinney.id.au  Fri Jul 17 06:03:29 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 20:03:29 +1000
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<h3p7en$n4f$02$1@news.t-online.com>
Message-ID: <87zlb3fwy6.fsf@benfinney.id.au>

Peter Otten <__peter__ at web.de> writes:

> Just thinking aloud: Write a patch for pydoc that looks up the
> base-class documentation.

That doesn't scale; I want the docstring to be discovered by the normal
interface (the ?__doc__? attribute) by *every* tool that gathers
docstrings from methods.

Also, I want to have this behaviour not for every method missing a
docstring, but only for selected methods.

> Of course that might be misleading when A.f and B.f are up to
> something completely different...

Exactly.

-- 
 \     ?Facts do not cease to exist because they are ignored.? ?Aldous |
  `\                                                            Huxley |
_o__)                                                                  |
Ben Finney


From sion at viridian.paintbox  Fri Jul 17 06:20:34 2009
From: sion at viridian.paintbox (Sion Arrowsmith)
Date: Fri, 17 Jul 2009 10:20:34 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
Message-ID: <SfY7m.5466$875.1940@newsfe20.ams2>

Jack Diederich  <jackdied at gmail.com> wrote:
>It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>dicts also raise an error if you try to LT them.

Since when?

Python 2.5.2 (r252:60911, Jan  4 2009, 17:40:26)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> d1 = dict((str(i), i) for i in range (10))
>>> d2 = dict((str(i), i) for i in range (20))
>>> d1 < d2
True
>>>

(Don't have a 2.6 or 3 to hand.)

Mind you, it makes even less sense for a regular dict than an
OrderedDict. And it's not like d1.items() < d2.items() is a
huge burden, if that's what you want dictionary comparison to
mean.

-- 
\S

   under construction



From jeanmichel at sequans.com  Fri Jul 17 07:06:26 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 17 Jul 2009 13:06:26 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <1247774222.4a5f860ec3cfa@mail.uh.cu>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<mailman.3216.1247751117.8015.python-list@python.org>	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>	<h3nk10$tvu$1@ger.gmane.org>
	<4A5F5759.4010600@sequans.com>
	<1247774222.4a5f860ec3cfa@mail.uh.cu>
Message-ID: <4A605B32.5080306@sequans.com>

Luis Alberto Zarrabeitia Gomez wrote:
> Quoting Jean-Michel Pichavant <jeanmichel at sequans.com>:
>
>   
>> Emile van Sebille wrote:
>>     
>>> On 7/16/2009 7:04 AM Unknown said...
>>>       
>>>> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
>>>>         
>>>>> daysInAdvance = int(inputVar) or 25
>>>>>           
>>>> I don't get it.  That doesn't work right when inputVar == "0".
>>>>
>>>>         
>>> Aah, but you didn't get to define right.  :)  For that particular 
>>> example 0 is not a valid response.
>>>       
>> When I was talking about such error prone form of boolean operations, I 
>> didn't expect to be right so quickly :p
>>     
>
> What do you mean by being "right so quickly", and "error prone" in this context?
> I would also ask "Unknown" why he believes that "int(intputVar) or 25" doesn't
> work right when inputVar == "0". The only false value that int() may return is
> zero, so the "or 25" clause is there only for that case. I can't see then how
> you think that is an error.
>   

I was saying that using boolean operators with object instead of boolean 
values is error prone, cause no language behaves he same way, and all 
behaviors are conventions difficult to figure out without diving deeply 
into the documentation (or being explained as it happened to me).

I think the initialization trick is an error, because I don't want 
foo(0) to set daysInAdvance to 25. I'll want it to set the attribute to 
0, cause 0 is a valid integer. 0 is a valid integer content, None 
wouldn't be a valid integer content.


JM


From bearophileHUGS at lycos.com  Fri Jul 17 07:11:10 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 17 Jul 2009 04:11:10 -0700 (PDT)
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
Message-ID: <639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>

Very good, thank you. I'll try it when I can.

Is Psyco3 going to borrow/steal some ideas/code from Unladen Swallow?

The problem I have with Psyco1.6 is that you can't use the normal
profilers to know how much seconds of running time is taken by each
function/method of your code.
Psyco1.6 has a profile() function, but I am not much able to use it
yet.
Can you tell me how to find a sorted list of the running time of all
functions/methods of a Psyco-digested program?

Bye and thank you,
bearophile


From andreengels at gmail.com  Fri Jul 17 07:33:03 2009
From: andreengels at gmail.com (Andre Engels)
Date: Fri, 17 Jul 2009 13:33:03 +0200
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
Message-ID: <6faf39c90907170433y7258eebcyeab03ff3021aaa8a@mail.gmail.com>

On Fri, Jul 17, 2009 at 7:31 AM, Xavier Ho<contact at xavierho.com> wrote:
> I have a simple class that generates prime numbers, using memorisation and
> iteration to generate the next prime number.
>
> In the class, I have defined a function that gives, say, the 5th prime
> number. Or the 1000th, it's still very fast. But the code isn't what I
> really like.
[...]
> My problem is that it's a "While True" loop, which I get a lot of "Don't do
> it!" In the light of making the code better, what could I do?

Where do you get these "Don't do it!"s? As far as I know, "while true"
loops are a very acceptable idiom for programming in Python (and
several other languages).


-- 
Andr? Engels, andreengels at gmail.com


From contact at xavierho.com  Fri Jul 17 07:38:55 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 19:38:55 +0800
Subject: Try... except....Try again?
In-Reply-To: <6faf39c90907170433y7258eebcyeab03ff3021aaa8a@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<6faf39c90907170433y7258eebcyeab03ff3021aaa8a@mail.gmail.com>
Message-ID: <2d56febf0907170438l6e38a503g74c3e0256404bb58@mail.gmail.com>

On Fri, Jul 17, 2009 at 7:33 PM, Andre Engels <andreengels at gmail.com> wrote:

>
> Where do you get these "Don't do it!"s? As far as I know, "while true"
> loops are a very acceptable idiom for programming in Python (and
> several other languages).
>

Hey Andre,

Friends, internet, common sense. Also... "while True" has a bad reputation.
But mostly outside influences.

But if it's okay, it's okay by me.. I can't think of an easier way to code
the "try loop" above, anyhow.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/d1ef7b6e/attachment.html>

From Larry.Martell at gmail.com  Fri Jul 17 08:07:04 2009
From: Larry.Martell at gmail.com (Larry.Martell at gmail.com)
Date: Fri, 17 Jul 2009 05:07:04 -0700 (PDT)
Subject: setup.py not found
Message-ID: <3be2bdce-680d-4b32-ad0c-ef46caf556e9@f10g2000vbf.googlegroups.com>

I'm trying to install a package (cx_Oracle) on a mac running 10.5.7.
I've done this on other platforms, but never on a mac. I followed the
instructions given, but when I try and run setup I get:

Apollo:instantclient_10_2 user$ python setup.py build
/System/Library/Frameworks/Python.framework/Versions/2.5/Resources/
Python.app/Contents/MacOS/Python: can't open file 'setup.py': [Errno
2] No such file or directory

Is there something else I have to install first to have this?

Thanks!


From dstanek at dstanek.com  Fri Jul 17 08:08:48 2009
From: dstanek at dstanek.com (David Stanek)
Date: Fri, 17 Jul 2009 08:08:48 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <h3p7en$n4f$02$1@news.t-online.com>
References: <87r5wggm0y.fsf@benfinney.id.au>
	<h3p7en$n4f$02$1@news.t-online.com>
Message-ID: <de32cc030907170508q60ed5fc4tfce14f7bc11e600e@mail.gmail.com>

On Fri, Jul 17, 2009 at 2:58 AM, Peter Otten<__peter__ at web.de> wrote:
> Ben Finney wrote:
>
>> Howdy all,
>>
>> The following is a common idiom::
>>
>> ? ? class FooGonk(object):
>> ? ? ? ? def frobnicate(self):
>> ? ? ? ? ? ? """ Frobnicate this gonk. """
>> ? ? ? ? ? ? basic_implementation(self.wobble)
>>
>> ? ? class BarGonk(FooGonk):
>> ? ? ? ? def frobnicate(self):
>> ? ? ? ? ? ? special_implementation(self.warble)
>>
>> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>> the method, the original docstring is not associated with it.
>>
>> Ideally there would be a way to specify that the docstring should be
>> inherited. The best I can come up with is::
>>
>> ? ? class BarGonk(FooGonk):
>> ? ? ? ? def frobnicate(self):
>> ? ? ? ? ? ? special_implementation(self.warble)
>> ? ? ? ? frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>>
>> but that violates DRY (the association between BarGonk and FooGonk is
>> being repeated), puts the docstring assignment awkwardly after the end
>> of the method instead of at the beginning where docstrings normally go,
>> and reads poorly besides.
>>
>> What is the most Pythonic, DRY-adherent, and preferably least-ugly
>> approach to override a method, but have the same docstring on both
>> methods?
>
> Just thinking aloud: Write a patch for pydoc that looks up the base-class
> documentation.
>
> B.f.__doc__ will continue to return None, but
>
> help(B.f) will show something like
>
> ? ?No documentation available for B.f.
>
> ? ?Help for A.f:
> ? ?yadda yadda
>
>
> Of course that might be misleading when A.f and B.f are up to something
> completely different...
>

This should never be the case. It violates LSP and would be very confusing to
readers of the code.


-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From dstanek at dstanek.com  Fri Jul 17 08:21:39 2009
From: dstanek at dstanek.com (David Stanek)
Date: Fri, 17 Jul 2009 08:21:39 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <02701ee5$0$5185$c3e8da3@news.astraweb.com>
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
	<87ljmogglz.fsf@benfinney.id.au>
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <de32cc030907170521m1ab5fe86h16c6e62ca157898d@mail.gmail.com>

On Fri, Jul 17, 2009 at 3:52 AM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Fri, 17 Jul 2009 12:58:48 +1000, Ben Finney wrote:
>
>>> Using a decorator in this manner requires repeating the super class
>>> name. ?Perhaps there is a way to get the bases of BarGonk, but I don't
>>> think so, because at the time that the decorator is called, BarGonk is
>>> not yet fully defined.
>>
>> Yes, I tried a few different ways, but within the decorator it seems the
>> function object is quite unaware of what class it is destined for.
>
>
> When the decorator is called, the function object is just a function
> object, not a method, so there is no concept of "what class it is
> destined for".
>
>>>> def dec(func):
> ... ? ? print type(func)
> ... ? ? try:
> ... ? ? ? ? ? ? print func.im_class
> ... ? ? except:
> ... ? ? ? ? ? ? print "no im_class"
> ... ? ? return func
> ...
>>>> class Test(object):
> ... ? ? @dec
> ... ? ? def spam(self):
> ... ? ? ? ? ? ? pass
> ...
> <type 'function'>
> no im_class
>>>> type(Test.spam)
> <type 'instancemethod'>
>>>> Test.spam.im_class
> <class '__main__.Test'>
>
>
> I suppose you could try to determine what namespace you're currently when
> the class is created, but that's surely going to be fragile and messy.
>

It isn't too bad. I got the idea to use the method's enclosing
scope[1] in my decorator[2] from DecoratorTools. I am working to
remove it because it make me sad, but it does work.

[1] http://code.google.com/p/snake-guice/source/browse/snakeguice/decorators.py#51
[2] http://code.google.com/p/snake-guice/source/browse/snakeguice/decorators.py#58


-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From seldon at katamail.it  Fri Jul 17 08:23:45 2009
From: seldon at katamail.it (Seldon)
Date: Fri, 17 Jul 2009 14:23:45 +0200
Subject: guessing file type
Message-ID: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>

Hello,  I need to determine programmatically a file type from its 
content/extension (much like the "file" UNIX command line utility)

I searched for a suitable Python library module, with little luck. Do 
you know something useful ?

Thanks in advance.
-- 
Seldon


From ben+python at benfinney.id.au  Fri Jul 17 08:28:41 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 22:28:41 +1000
Subject: guessing file type
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
Message-ID: <87iqhrfq86.fsf@benfinney.id.au>

Seldon <seldon at katamail.it> writes:

> Hello,  I need to determine programmatically a file type from its
> content/extension (much like the "file" UNIX command line utility)

The Unix ?file(1)? program does its magic with a library called ?magic?
and a corresponding database.

> I searched for a suitable Python library module, with little luck. Do
> you know something useful ?

This package <URL:http://pypi.python.org/pypi/python-magic> provides
Python bindings to libmagic.

-- 
 \     ?Unix is an operating system, OS/2 is half an operating system, |
  `\    Windows is a shell, and DOS is a boot partition virus.? ?Peter |
_o__)                                                        H. Coffin |
Ben Finney


From python.list at tim.thechases.com  Fri Jul 17 08:36:29 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 17 Jul 2009 07:36:29 -0500
Subject: guessing file type
In-Reply-To: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
Message-ID: <4A60704D.8080803@tim.thechases.com>

> Hello,  I need to determine programmatically a file type from its 
> content/extension (much like the "file" UNIX command line utility)
> 
> I searched for a suitable Python library module, with little luck. Do 
> you know something useful ?

Are you looking for something comprehensive?  Or are you just 
looking for particular file-types that your application can 
handle?  I'd start with the python mimetypes library[1] which 
does detection based on extensions (to which you can add your own 
mappings).  For sniffing by content, there are a wide variety of 
document types, I don't know of any pre-existing library.  The 
first couple bytes can often tell you something, but you'd have 
to go digging into the source for "file" to see what it does.

-tkc

[1]
http://docs.python.org/library/mimetypes.html





From van.lindberg at gmail.com  Fri Jul 17 08:39:22 2009
From: van.lindberg at gmail.com (VanL)
Date: Fri, 17 Jul 2009 07:39:22 -0500
Subject: guessing file type
In-Reply-To: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
Message-ID: <h3prdq$r2n$1@ger.gmane.org>

Seldon wrote:
> Hello,  I need to determine programmatically a file type from its 
> content/extension (much like the "file" UNIX command line utility)
> 
> I searched for a suitable Python library module, with little luck. Do 
> you know something useful ?

Python-magic (http://pypi.python.org/pypi/python-magic/0.1) wraps 
libmagic -- the same thing that "file" uses -- but getting it on windows 
is a pain. I have never been able to do it, anyway.

A more cross-platform library with a similar scope is hachoir. Still 
seems to be available from PyPI, but the website seems to have fallen 
off the 'net.



From victorsubervi at gmail.com  Fri Jul 17 09:02:25 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Fri, 17 Jul 2009 10:02:25 -0300
Subject: Auto Send URL
Message-ID: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>

Hi;
I am trying to script code that automatically sends a Web site visitor to an
URL. Specifically, when they enter a value in a search box, I have that form
sent to a script that writes an URL acceptable to Google, then I want to
send the visitor off without him having to click another button. How do I do
this?
TIA,
Victor
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/2b88a291/attachment.html>

From python at mrabarnett.plus.com  Fri Jul 17 09:17:20 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 14:17:20 +0100
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
Message-ID: <4A6079E0.8040003@mrabarnett.plus.com>

Xavier Ho wrote:
> I have a simple class that generates prime numbers, using memorisation 
> and iteration to generate the next prime number.
> 
> In the class, I have defined a function that gives, say, the 5th prime 
> number. Or the 1000th, it's still very fast. But the code isn't what I 
> really like.
> 
>     def nPrime(self, n):
>         "Returns nth prime number, the first one being 2, where n = 0. 
> When n = 1, it returns 3."
>         while True:
>             try:
>                 return self.primes[n]
>             except:
>                 self.next()
> 
> The next() function generates the next prime, and appends it into 
> primes. This way, it keeps trying to append until the nth prime 
> requested exist, and returns it.
> 
> My problem is that it's a "While True" loop, which I get a lot of "Don't 
> do it!" In the light of making the code better, what could I do?
> 
I wouldn't use a bare "except". What if you had written "prims" instead
of "primes"? It would catch AttributeError and produce the next prime, 
repeating until it ran out of memory.



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 09:28:00 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 13:28:00 GMT
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
Message-ID: <02706d8f$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 00:34:00 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> It is very useful to be able to write e.g.: 
>>
>> if header or body or footer:
>>     print assemble_page(header, body, footer)
>>
>> and have empty strings to be equivalent to False.
> 
> Why doesn't assemble_page properly handle the case where header, body,
> and footer are all empty?  That would let you eliminate the if.  "Make
> sure your code 'does nothing' gracefully" (Kernighan and Plauger).

You mean something like this?

def assemble_page(header, body, footer):
    if header or body or footer:
        do_lots_of_expensive_processing()
    else:
        do_nothing_gracefully()

Sure, why not?

Whatever way you do it, my point is that it is very useful to perform 
branching tests on non-Boolean objects. Wherever you put the test, being 
able to write:

    if header or body or footer:

is a huge improvement over:

    if (header != '') or (body != '') or (footer != ''):



-- 
Steven


From edreamleo at charter.net  Fri Jul 17 09:36:59 2009
From: edreamleo at charter.net (Edward K Ream)
Date: Fri, 17 Jul 2009 08:36:59 -0500
Subject: ANN: Leo 4.6 final released
Message-ID: <q8%7m.17824$FP2.4210@newsfe05.iad>

Leo 4.6 final is now available at:
http://sourceforge.net/project/showfiles.php?group_id=3458&package_id=29106

Leo is a text editor, data organizer, project manager and much more. See:
http://webpages.charter.net/edreamleo/intro.html

The highlights of Leo 4.6:
--------------------------

- Cached external files *greatly* reduces the time to load .leo files.
- Leo now features a modern Qt interface by default.
  Leo's legacy Tk interface can also be used.
- New --config, --file and --gui command-line options.
- Leo tests syntax of .py files when saving them.
- Leo can now open any kind of file into @edit nodes.
- @auto-rst nodes allow easy editing of reStructuredText files.
- Properties of commanders, positions and nodes simplify programming.
- Improved Leo's unit testing framework.
- Leo now requires Python 2.5 or later.
- Dozens of small improvements and bug fixes.

Links:
------
Leo:      http://webpages.charter.net/edreamleo/front.html
Forum:    http://groups.google.com/group/leo-editor
Download: http://sourceforge.net/project/showfiles.php?group_id=3458
Bzr:      http://code.launchpad.net/leo-editor/
Quotes:   http://webpages.charter.net/edreamleo/testimonials.html

--------------------------------------------------------------------
Edward K. Ream   email:  edreamleo at yahoo.com
Leo: http://webpages.charter.net/edreamleo/front.html
--------------------------------------------------------------------




From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 09:42:44 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 13:42:44 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com> <h3na3s$qjr$1@ger.gmane.org>
	<mailman.3218.1247752436.8015.python-list@python.org>
Message-ID: <02707103$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:

> Python has extended the algebra definition of "or" and "and" top any
> type, but it is so unintuitive (I'm no LISP programmer).

I disagree. The Something/Nothing dichotomy is so intuitive to me that I 
would hate to go back to a language that only accepted booleans as 
arguments to `if`.


> I think than 
> using the short-circuiting mechanism of bool operators along with the 
> python tricks is just error prone and may result in bug difficult to 
> spot, unless you are very aware of all python boolean mechanisms.

In other words, if you don't know how Python behaves, you will make 
mistakes.

Of course you will. That applies to *anything* -- if you don't know how 
it works, you will make mistakes.

Given three result codes, where 0 means "no error" and an arbitrary non-
zero integer means some error, it is simple and easy to write:

failed = result_1 or result_2 or result_3

The equivalent:

failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
# or if you prefer:
succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)

are longer and more difficult to read and easier to get wrong. Even worse 
are tricks like this:

failed = (result_1 + result_2 + result_3) != 0

This obscures the fact that the result codes are flags and makes it seem 
like (flag + flag) is meaningful.



-- 
Steven


From justin.mailinglists at gmail.com  Fri Jul 17 09:58:13 2009
From: justin.mailinglists at gmail.com (Justin Ezequiel)
Date: Fri, 17 Jul 2009 06:58:13 -0700 (PDT)
Subject: guessing file type
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it> 
	<mailman.3274.1247834383.8015.python-list@python.org>
Message-ID: <7c7ab0ce-ffea-46da-b495-8ebf8e63ecf6@32g2000yqj.googlegroups.com>

On Jul 17, 8:39?pm, VanL <van.lindb... at gmail.com> wrote:
> Seldon wrote:
> > Hello, ?I need to determine programmatically a file type from its
> > content/extension (much like the "file" UNIX command line utility)
>
> > I searched for a suitable Python library module, with little luck. Do
> > you know something useful ?
>

I've used the magic.py module by "Jason Petrone" before.
http://tinyurl.com/ldho8m


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 10:12:37 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 14:12:37 GMT
Subject: Try... except....Try again?
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
Message-ID: <02707804$0$5185$c3e8da3@news.astraweb.com>

Apologies for breaking threading, but the original post hasn't showed up 
on my ISP's news server.

Xavier Ho wrote:
> I have a simple class that generates prime numbers, using memorisation
> and iteration to generate the next prime number.
[...]
> The next() function generates the next prime, and appends it into
> primes. This way, it keeps trying to append until the nth prime
> requested exist, and returns it.
> 
> My problem is that it's a "While True" loop, which I get a lot of
>> "Don't do it!"

There's nothing wrong with "while True" loops. They are useful in two 
situations:

(1) Where you want to loop forever.

(2) Where you want to loop until some complex event takes place, which 
can't easily be written using "while condition".

Neither of these cases holds for your code, so although there's nothing 
wrong with "while True", in your case I'd avoid it.


> In the light of making the code better, what could I do?


(1) Explicitly loop the correct number of times.
(2) Only catch IndexError.

def nPrime(self, n):
    for i in xrange(len(self.primes), n+1):
        self.next()
    return self.primes[n]



-- 
Steven


From http  Fri Jul 17 10:12:51 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 07:12:51 -0700
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <7xab33s8ik.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> def assemble_page(header, body, footer):
>     if header or body or footer:
>         do_lots_of_expensive_processing()
>     else:
>         do_nothing_gracefully()

Why should the processing be expensive if all three fields are empty?

>     if header or body or footer:
> is a huge improvement over:
>     if (header != '') or (body != '') or (footer != ''):

Doesn't really seem any better.  There's always something like

   if any(p != '' for p in [header, body, footer, otherthing1, ...])

if the number of components gets larger.


From kyrie at uh.cu  Fri Jul 17 10:19:51 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Fri, 17 Jul 2009 10:19:51 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A605B32.5080306@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<1247774222.4a5f860ec3cfa@mail.uh.cu>
	<4A605B32.5080306@sequans.com>
Message-ID: <200907171019.52471.kyrie@uh.cu>

On Friday 17 July 2009 07:06:26 am Jean-Michel Pichavant wrote:
>
> I was saying that using boolean operators with object instead of boolean
> values is error prone, cause no language behaves he same way,

I don't know of many languages that actively promote the duck typing concept, 
are as highly dynamic as python, have the "metaclass" concept, treats almost 
all language concepts as first class citizens (including functions and 
classes), and so on. And don't get me started on assignment (which I consider 
very natural, by the way, but apparently most of the popular languages have 
pretty unnatural assignments).

It is error prone if you are expecting the result to be a bool instead of just
behaving like one (it is certainly unexpected, but you shouldn't be expecting 
to get an instance of certain class anyway, for most of python's operations). 
And it is confusing if you are reading the "int(inputVar) or 25" line and 
have no idea of what it means (but once you know it, it becomes very 
readable, almost plain english).

> and all 
> behaviors are conventions difficult to figure out without diving deeply
> into the documentation (or being explained as it happened to me).

That happens with many new concepts. Welcome to python, I guess... if you are 
willing to shake some of your expectations from previous programming 
languages, you will enjoy it. My [little] experience teaching python tells me 
that "duck typing", "non-enforced encapsulation" and "everything is an 
object" are the hardest to accept for the C# folk at my faculty, but once 
past it, they (the few of them who don't leave the course after that) really 
enjoy the language.

> I think the initialization trick is an error, because I don't want
> foo(0) to set daysInAdvance to 25. I'll want it to set the attribute to
> 0, cause 0 is a valid integer. 0 is a valid integer content, None
> wouldn't be a valid integer content.

Well, that wouldn't be a problem with "or", but with the programmer.

The exact same behaviour could be obtained with

if int(inputValue) == 0:
    inputValue = 25

and no "or" involved.

However, using only

inputValue = inputValue or 25

could have been an error if you only wanted 25 in case inputValue is None.

(the "or trick" implies certain trust in that the object you have in hand has 
a reasonable definition of truth value).

-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From jeanmichel at sequans.com  Fri Jul 17 10:34:57 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 17 Jul 2009 16:34:57 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <02707103$0$5185$c3e8da3@news.astraweb.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>
	<h3na3s$qjr$1@ger.gmane.org>	<mailman.3218.1247752436.8015.python-list@python.org>
	<02707103$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A608C11.1020901@sequans.com>

Steven D'Aprano wrote:
> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>
>
> Given three result codes, where 0 means "no error" and an arbitrary non-
> zero integer means some error, it is simple and easy to write:
>
> failed = result_1 or result_2 or result_3
>
> The equivalent:
>
> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
> # or if you prefer:
> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>
>   
[snip]

This is, I guess, where we disagree. I find the second proposal less 
error prone, and universally understandable unlike the first one. It may 
be verbose, it may look even lame to some people, but in the end this is 
perfectly reliable, because you manipulate only False or True within the 
boolean operations.

The first form does not clearly show what is the failed criteria. It 
just happens by coincidence that in this case the failed criteria 
matches the Nothingness of result_1, result_2, result_3. What if results 
may be 'OK' or 'KO'.

failed = result_1 or result_2 or result_3
won't work.

failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is 
lame but reliable.


JM


From contact at xavierho.com  Fri Jul 17 10:35:24 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 22:35:24 +0800
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
Message-ID: <2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>

oops, wrong address.

When will reply-to tag appear on the Python mailing list? =/

Good idea, Steven and MRAB.

I changed my code to the following:

    def nPrime(self, n):
        "Returns nth prime number, the first one being 2, where n = 0. When
n = 1, it returns 3."
        for x in range(n+2):
            try:
                return self.primes[n]
            except IndexError:
                self.next()

And it's definitely better. Thanks a ton guys.

(n+2 because after looping the maximum number of times, it needs to try
returning the value again.)

It works just as well as the previous version, but slightly safer on my
part... and I can adapt this in my future coding habits.

Thanks again.


Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/b5fa2eaf/attachment.html>

From ethan at stoneleaf.us  Fri Jul 17 10:51:05 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 17 Jul 2009 07:51:05 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A608C11.1020901@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<h3na3s$qjr$1@ger.gmane.org>	<mailman.3218.1247752436.8015.python-list@python.org>	<02707103$0$5185$c3e8da3@news.astraweb.com>
	<4A608C11.1020901@sequans.com>
Message-ID: <4A608FD9.908@stoneleaf.us>

Jean-Michel Pichavant wrote:
> Steven D'Aprano wrote:
> 
>> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>>
>>
>> Given three result codes, where 0 means "no error" and an arbitrary non-
>> zero integer means some error, it is simple and easy to write:
>>
>> failed = result_1 or result_2 or result_3
>>
>> The equivalent:
>>
>> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
>> # or if you prefer:
>> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>>
>>   
> 
> [snip]
> 
> This is, I guess, where we disagree. I find the second proposal less 
> error prone, and universally understandable unlike the first one. 

Careful!  The very few (if any) things in this world that can be 
considered "universally understandable" do *not* include any programming 
language!  :)

> It may 
> be verbose, it may look even lame to some people, but in the end this is 
> perfectly reliable, because you manipulate only False or True within the 
> boolean operations.
> 
> The first form does not clearly show what is the failed criteria. It 
> just happens by coincidence that in this case the failed criteria 
> matches the Nothingness of result_1, result_2, result_3. What if results 
> may be 'OK' or 'KO'.

As the programmer, particularly a Python programmer, you should be 
taking advantage of Python's strengths, of which this is one.  If, as 
you say, some function uses a "something" value to indicate an 
undesirable result, then you have to use something akin to your last 
statement.


~Ethan~

> 
> failed = result_1 or result_2 or result_3
> won't work.
> 
> failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is 
> lame but reliable.
> 
> 
> JM



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 10:54:53 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 14:54:53 GMT
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
Message-ID: <027081ec$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 07:12:51 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> def assemble_page(header, body, footer):
>>     if header or body or footer:
>>         do_lots_of_expensive_processing()
>>     else:
>>         do_nothing_gracefully()
> 
> Why should the processing be expensive if all three fields are empty?

Since I haven't specified an implementation for assemble_page, it could 
be doing *anything*. Perhaps it has to talk to a remote database over a 
slow link, perhaps it generates 300 lines of really inefficient HTML code 
with no content, perhaps it sends a print job to a printer which then 
warms up, cleans the print heads, and ejects a blank piece of paper.

Why does it matter? The example is about the `if` test, not about the 
function assemble_page().



-- 
Steven


From jackdied at gmail.com  Fri Jul 17 11:02:09 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Fri, 17 Jul 2009 11:02:09 -0400
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
Message-ID: <b8e622740907170802k24cdb6abm41f781dae9a60236@mail.gmail.com>

On Fri, Jul 17, 2009 at 10:35 AM, Xavier Ho<contact at xavierho.com> wrote:

> I changed my code to the following:
>
> ??? def nPrime(self, n):
> ??????? "Returns nth prime number, the first one being 2, where n = 0. When
> n = 1, it returns 3."
> ??????? for x in range(n+2):
> ??????????? try:
> ??????????????? return self.primes[n]
> ??????????? except IndexError:
> ??????????????? self.next()
>
> And it's definitely better. Thanks a ton guys.
>
> (n+2 because after looping the maximum number of times, it needs to try
> returning the value again.)

def nPrime(self, n):
    while len(self.primes) < n:
         self.next()
    return self.primes[n]

If you use an off-the-shelf prime number generator fucntion[1] that
returns consecutive primes the method collapses into a simple
function.

def nPrime(n, primes=[], next_prime=eratosthenes().next):
    while len(primes) < n:
        primes.append(next_prime())
    return primes[n]

-Jack

[1] http://www.catonmat.net/blog/solving-google-treasure-hunt-prime-number-problem-four/#comment-3075
     There is a deque implementation that is faster still but I can't
find a link.


From python at mrabarnett.plus.com  Fri Jul 17 11:09:03 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 16:09:03 +0100
Subject: Einstein summation notation
In-Reply-To: <10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <4A60940F.6090604@mrabarnett.plus.com>

koranthala wrote:
>> That test was designed to treat None as a boolean False, without
>> noticing that numeric 0 is also treated as False and could make the
>> test do the wrong thing.  This is an extremely common type of error.
> 
> Actually, I felt that 0 not being considered False would be a better
> option.
> I had lot of instances where 0 is a valid value and always I had to
> put checks specifically for that.
> For me, None and False should be equal to False in if checks, every
> thing else being considered True.
> 
> Can someone let me know why 0 is considered equal to False?
> There should be real good reasons for it, only that I cannot think of
> one.

Python did always have True and False.


From gabriel.rossetti at arimaz.com  Fri Jul 17 11:19:36 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 17 Jul 2009 17:19:36 +0200
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <m2eisfu2m0.fsf@cs.uu.nl>
References: <mailman.3221.1247757153.8015.python-list@python.org>	<m21voguvxz.fsf@cs.uu.nl>	<mailman.3261.1247811927.8015.python-list@python.org>
	<m2eisfu2m0.fsf@cs.uu.nl>
Message-ID: <4A609688.9080201@arimaz.com>

Piet van Oostrum wrote:
>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>             
>
>   
>> GR> I have a 1-1 relation, I have a thread reading msgs from a network socket
>> GR> and a method waiting for an answer to arrive (see my thread
>> GR> "Threading.Condition problem"). I would like to be able to have a timeout
>> GR> as to not block forever, so the idea is to check if I returned because of a
>> GR> timeout or not.
>>     
>
> So that case is easy I think. After the wait just check if the answer
> has arrived.
>   
The problem is other answers could arrive that are not the one I want. 
Maybe I could check if I got the answer, if not then check how much time 
has elapsed, and if it's grater or equal to the timeout consider it a 
timeout. I still think a return value would be better though.



From ethan at stoneleaf.us  Fri Jul 17 11:20:41 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 17 Jul 2009 08:20:41 -0700
Subject: Einstein summation notation
In-Reply-To: <7xab33s8ik.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<kmr2uu.d1t@spenarnc.xs4all.nl>	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>	<02701951$0$5185$c3e8da3@news.astraweb.com>	<7xljmnahlj.fsf@ruckus.brouhaha.com>	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
Message-ID: <4A6096C9.4070703@stoneleaf.us>

Paul Rubin wrote:
> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> 
>>def assemble_page(header, body, footer):
>>    if header or body or footer:
>>        do_lots_of_expensive_processing()
>>    else:
>>        do_nothing_gracefully()
> 
> 
> Why should the processing be expensive if all three fields are empty?
> 
> 
>>    if header or body or footer:
>>is a huge improvement over:
>>    if (header != '') or (body != '') or (footer != ''):
> 
> 
> Doesn't really seem any better.  There's always something like
> 
>    if any(p != '' for p in [header, body, footer, otherthing1, ...])
> 
> if the number of components gets larger.

Or if any(p for p in [header, body, footer, whatever, ...])

Which is even nicer!  :)  Particularly if header, et al, are some more 
complicated objects which don't easily generate strings, but do easily 
know whether they are Something or Nothing.

I suppose some of these discussions are based more on one's personal 
requirements (using several languages, just a couple, or just Python), 
and whether one wants to achieve Mastery of Python, or just be 
Proficient.  Neither choice is wrong, and wanting Mastery, of course, 
does not mean not wanting improvements, etc.  It does, however, require 
a deep understanding of not just the mechanics, but the philosophy of 
the language.

Mind you, I am nowhere near Mastery just yet (okay, okay, I have a 
_long_ way to go! ;), but I love the philosophy of Python, it's 
simplicity, and the *entirety* of the Zen.

~Ethan~


From malaclypse2 at gmail.com  Fri Jul 17 11:26:18 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Fri, 17 Jul 2009 11:26:18 -0400
Subject: Einstein summation notation
In-Reply-To: <4A60940F.6090604@mrabarnett.plus.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<4A60940F.6090604@mrabarnett.plus.com>
Message-ID: <16651e80907170826r13856d5ag48eb299b70574450@mail.gmail.com>

On Fri, Jul 17, 2009 at 11:09 AM, MRAB<python at mrabarnett.plus.com> wrote:

> Python did always have True and False.

Only if "always" means "since python 2.2.1".

See: http://www.python.org/doc/2.3/whatsnew/section-bool.html and
http://www.python.org/dev/peps/pep-0285/ for details.

-- 
Jerry


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 11:30:11 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 15:30:11 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com> <h3na3s$qjr$1@ger.gmane.org>
	<mailman.3218.1247752436.8015.python-list@python.org>
	<02707103$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3280.1247841310.8015.python-list@python.org>
Message-ID: <02708a32$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 16:34:57 +0200, Jean-Michel Pichavant wrote:

> Steven D'Aprano wrote:
>> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>>
>>
>> Given three result codes, where 0 means "no error" and an arbitrary
>> non- zero integer means some error, it is simple and easy to write:
>>
>> failed = result_1 or result_2 or result_3
>>
>> The equivalent:
>>
>> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0) # or if
>> you prefer:
>> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>>
>>
> [snip]
> 
> This is, I guess, where we disagree. I find the second proposal less
> error prone, and universally understandable unlike the first one. It may
> be verbose, it may look even lame to some people, but in the end this is
> perfectly reliable, because you manipulate only False or True within the
> boolean operations.

Because it is verbose, it is more error-prone. The more code you have to 
write, the more opportunities you have to make mistakes.

(This holds up to a point, beyond which being more and more terse also 
leads to more errors.)

Boolean algebra is notorious for programmer errors. The more complicated 
the boolean expression, the more often programmers get it wrong. The more 
book-keeping they have to do, the easier it is to get it wrong. All those 
(result != 0) comparisons are mere book-keeping, they don't add anything 
to the code except to force the flag to be True or False.



> The first form does not clearly show what is the failed criteria.

Of course it does: at least one of the three result codes is non-zero. As 
a bonus, failed will be assigned the first non-zero result code (if any).

Your preferred form, on the other hand, folds all the possible error 
codes into True, throwing away useful information:

>>> result_1 = 0  # success
>>> result_2 = 0
>>> result_3 = 15  # failure
>>> failure = result_1 or result_2 or result_3
>>> failure
15
>>> failure = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
>>> failure
True



> It
> just happens by coincidence that in this case the failed criteria
> matches the Nothingness of result_1, result_2, result_3. What if results
> may be 'OK' or 'KO'.

Obviously the test you write depends on the data you have to work with. 
Do you think that's surprising?


> failed = result_1 or result_2 or result_3 won't work.

Not in the example you gave, no. Although if I had to work with lots and 
lots of strings of the form 'OK' and 'KO', I'd consider sub-classing 
string:

>>> class OKString(str):
...     def __nonzero__(self):
...         if self == 'OK': return True
...         elif self == 'KO': return False
...         else:
...             raise ValueError('invalid result code')
...
>>>
>>> a = OKString('OK')
>>> b = OKString('KO')
>>> c = OKString('KO')
>>> if a and b and c:
...     print "Success!"
... else:  print "Failed!"
...
Failed!


(I wouldn't bother if I only needed one or two such tests, but if I had 
lots of them, I'd consider it.)

 
> failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is
> lame but reliable.


Yes, it's reliably complicated, reliably easy to get wrong, reliably 
harder to read, and it reliably throws away information.

But apart from those disadvantages, it does the job you want it to do.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 11:32:41 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 15:32:41 GMT
Subject: Einstein summation notation
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<mailman.3284.1247843327.8015.python-list@python.org>
Message-ID: <02708ac8$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 16:09:03 +0100, MRAB wrote:

> Python did always have True and False.

$ python1.5
Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
4.1.2-27)] on linux2
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>> True, False
Traceback (innermost last):
  File "<stdin>", line 1, in ?
NameError: True



-- 
Steven


From mooniitk at gmail.com  Fri Jul 17 11:42:19 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Fri, 17 Jul 2009 17:42:19 +0200
Subject: 'del' function for Dictionary
Message-ID: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>

Hi all,

I wanted to know whether there is a more efficient way to delete an entry
from a dictionary (instead of using the 'del' function), because after
analyzing the time taken by the code, it seems to me that the 'del' function
takes most of the time. I might be incorrect as well.
Kindly help me in this regard.

Cheers,
Mayank

-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/0ebdc9af/attachment.html>

From contact at xavierho.com  Fri Jul 17 11:50:14 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 23:50:14 +0800
Subject: Try... except....Try again?
In-Reply-To: <b8e622740907170802k24cdb6abm41f781dae9a60236@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
	<b8e622740907170802k24cdb6abm41f781dae9a60236@mail.gmail.com>
Message-ID: <2d56febf0907170850w5941170fpa527571f7fc241ef@mail.gmail.com>

On Fri, Jul 17, 2009 at 11:02 PM, Jack Diederich <jackdied at gmail.com> wrote:

>
> If you use an off-the-shelf prime number generator fucntion[1] that
> returns consecutive primes the method collapses into a simple
> function.
>
> def nPrime(n, primes=[], next_prime=eratosthenes().next):
>    while len(primes) < n:
>        primes.append(next_prime())
>    return primes[n]
>
> -Jack
>
> [1]
> http://www.catonmat.net/blog/solving-google-treasure-hunt-prime-number-problem-four/#comment-3075
>     There is a deque implementation that is faster still but I can't
> find a link.


Jack, thanks for the link, I'll definitely look into it.

The function is currently implemented in a class I wrote myself, which is a
generator class that does exactly the same thing in the next() function. I
didn't post the code here because it wasn't in the scope of this thread, but
I'm sure others have done a lot better and much more efficient algorithms.

The nPrime method uses the nature of the iteration and checks if a value
already exists (ie generated before) and return that value; otherwise it
iterates again. This way, I don't have to iterate from n=2 and on every
time, which makes generation time linear.

However, I just gave the link's code a quick try. It was at least 10x times
faster than my code to generate 100000 prime numbers - I'll have a closer
look.

Thanks a great deal.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/b6844c29/attachment.html>

From motoom at xs4all.nl  Fri Jul 17 11:54:47 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Fri, 17 Jul 2009 17:54:47 +0200
Subject: 'del' function for Dictionary
In-Reply-To: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
References: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
Message-ID: <4A609EC7.6060007@xs4all.nl>

mayank gupta wrote:
> after analyzing the time taken by the code,
What code?




From dan.eloff at gmail.com  Fri Jul 17 12:11:18 2009
From: dan.eloff at gmail.com (Eloff)
Date: Fri, 17 Jul 2009 09:11:18 -0700 (PDT)
Subject: Find first matching substring
Message-ID: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>

Almost every time I've had to do parsing of text over the last 5 years
I've needed this function:

def find_first(s, subs, start=None, end=None):
    results = [s.find(sub, start, end) for sub in subs]
    results = [r for r in results if r != -1]
    if results:
        return min(results)

    return -1

It finds the first matching substring in the target string, if there
is more than one match, it returns the position of the match that
occurs at the lowest index in the string.

Has anyone else had problems where they could have applied this
function?

It seems to me that python's find (and rfind, index, rindex) could be
modified (the same way that startswith and endswith have been) to
behave this way if a tuple were passed. Do other's agree that this
would be desirable?

Thanks,
Dan


From http  Fri Jul 17 12:15:17 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 09:15:17 -0700
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
	<027081ec$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <7xljmn5lre.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Since I haven't specified an implementation for assemble_page, it could 
> be doing *anything*. Perhaps it has to talk to a remote database over a 
> slow link, perhaps it generates 300 lines of really inefficient HTML code 
> with no content, perhaps it sends a print job to a printer which then 
> warms up, cleans the print heads, and ejects a blank piece of paper.

That sounds like a code smell to me.  If the function is supposed to
print a piece of paper when any of those strings are nonempty, it
should also print one when they are all empty.  Of the different
values a string can have, 'foo', 'bar', and '' are all perfectly good
values and should all be treated the same way.  

If you want an absent string to work differently than a present one,
that's separate from empty vs nonempty, and overloading the empty
string to mean "absent" is another antipattern.  Maybe what you really
want is a list of page constituents that are present:

   page_parts = [header, body, footer]

If all the constituents are absent, then page_parts is the empty list,
so you would just test for page_parts being empty.

> Why does it matter? The example is about the `if` test, not about the 
> function assemble_page().

Because of the notion that the code should "do nothing" gracefully.
The presence of that 'if' test is ungraceful, so its better to look
for ways to eliminate it than slickify it.


From wells at submute.net  Fri Jul 17 12:31:10 2009
From: wells at submute.net (Wells Oliver)
Date: Fri, 17 Jul 2009 11:31:10 -0500
Subject: Question regarding style/design..
Message-ID: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>

Sometimes I see relatively small application, generally task scripts,
written as essentially a list of statements. Other times, I see them neatly
divided into functions and then the "if __name__ == '__main__':" convention.
Is there a preference? Is there an... application scope such that the
preference shifts from the former to the latter? I understand the use of the
__name__ == 'main' convention for building unit tests, but I'm mixed on
using it in scripts/small applications.
Thanks for any thoughts!

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/ec934d8c/attachment.html>

From mabdelkader at gmail.com  Fri Jul 17 12:32:12 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Fri, 17 Jul 2009 12:32:12 -0400
Subject: A multi-threaded file searcher for processing large text files
Message-ID: <148918f0907170932w7f1a7f3br78a70845e9050566@mail.gmail.com>

I'm building a threaded file searcher that uses some of Fredrik Lundh's (
http://effbot.org/zone/wide-finder.htm) suggestions for parsing text very
quickly in pure python, as I have about a 10GB log file to parse every day.
A naiive approach would be to just parse the 1MB chunks, add the results
into a list, and just traverse that list.

I want to take this idea a bit further. I want to process results as they're
being found. A great way to implement this is to use the Queue class that
python provides. My idea is to exploit the iterator protocol to have it
block until a result is found, if any, and return the result until we're
finished parsing the file then we can raise StopIteration.

My idea is sort of similar to a producer / consumer, but it follows
something of this idiom:
  producer produces the file chunks
  consumer consumes the file chunks
     -> consumer parsers the file chunks and produces results
  class waits on the production of the original consumer and processes it as
they come.

I am having a bit of trouble with the concurrency, but I'm using this as an
exercise to understand how concurrency works from a broader scale. I am not
trying to get into a debate of whether this is really needed or a
python-concurrency debate:)

Without further ado, my class is as follows:

class ThreadedFileSearcher(object):
    def __init__(self, filename, rx_pat, blocking_timeout = 10):
        self.name = filename
        self.pattern = rx_pat
        self.blocking_timeout = blocking_timeout

        #need to find a better way to do this with more threads that can
return
        #stable results (aka chunks are in order)
        self._thread_count = 1

        #the queues
        self._results = Queue.Queue()
        self._queue = Queue.Queue()

        #returns the get_chunk() implementation
        self._engine = LogParsingEngine(filename)

        #start acquiring file offsets for the file
        #as daemon threads
        self._initialize_worker_threads(self._prime_queue)

        #experimental...should probably be some type of conditional variable
        self._stop_processing = False

    def __iter__(self):
        #start the worker threads
        self._initialize_worker_threads(self._target_worker)
        return self.next()

    def _initialize_worker_threads(self, callback):
        #should really use just one thread
        for i in xrange(self._thread_count):
            t = threading.Thread(target=callback)
            t.setDaemon(True)
            t.start()

    def _prime_queue(self):
        """put code chunk offsets on the queue"""
        #get_chunks() just returns 1MB offsets in the file
        for chunk in self._engine.get_chunks():
            self._queue.put(chunk)

    def _target_worker(self):
        """code chunk to parse queue"""
        #loop infinitely
        while True:
            try:
                #get next chunk offset from the queue
                start_pos, bytes_to_read = self._queue.get(
                                              timeout=self.blocking_timeout
                                           )
            except (TypeError, Queue.Empty):
                #None was returned from the .get()
                #this will throw a TypeError as it tries to unpack None
                #or the Queue was empty
                self._stop_processing = True
                #exit loop
                break

            #process the cunk here
            f = open(self.name, 'r')
            f.seek(start_pos)
            #find all matching lines in the chunk
            for chunk in self.pattern.findall(f.read(bytes_to_read)):
                #an non-overlapping matches of self.pattern
                #placed on the queue as a string
                self._results.put(chunk)
            f.close()

            #done!
            self._queue.task_done()

    def next(self):
        while True:
            try:
                #wait for the results to be put on
                matchedlist =
self._results.get(timeout=self.blocking_timeout)
            except Queue.Empty:
                #if the worker thread finished
                if self._stop_processing:
                    raise StopIteration
            else:
                self._results.task_done()
                yield matchedlist

To use the following class, I wanted to have some kind of interface like
this:

regex = re.compile("-{3}Processing..-{3}") #---Processing..---
f = ThreadedFileSearcher("LogFile.log", regex)
for line in f:
    #guaranteed to be a line that matches regex
    #process something...
    print line


I am looking for some suggestions, comments, and better ways to modify this.


One thing someone will realize when using this class is that the initial
parsing will be incredibly quick, but if the blocking_timeout is set to 10,
then there will be a 10second wait at the end to test if the worker threads
should set the stop conditions. A glaring hole leading from this is if the
blocking_timeout is set to something like 1second and by the time a user
attempts to iterate over the results, the worker threads will prematurely
stop processing.

Speaking of stop processing, should self._stop_processing be a conditional
variable. Right now it's a boolean, and I think that's pretty hacky. I don't
like the StopIteration stop condition, maybe someone has a better
suggestion?

A future modification I'm looking for is to launch multiple threads that
process different parts of the file (different chunks) and return their
results, probably indexed by their chunk offset. Then I can iterate over
that sequentially. I think that would be a trivial parallel optimization.

Thoughts? Comments?

Thanks very much,

Mahmoud Abdelkader
mahmoud at linux.com
http://blog.mahmoudimus.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/75ba6329/attachment.html>

From emile at fenx.com  Fri Jul 17 12:55:39 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 17 Jul 2009 09:55:39 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A608C11.1020901@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<h3na3s$qjr$1@ger.gmane.org>	<mailman.3218.1247752436.8015.python-list@python.org>	<02707103$0$5185$c3e8da3@news.astraweb.com>
	<4A608C11.1020901@sequans.com>
Message-ID: <h3qa8s$cn2$1@ger.gmane.org>

On 7/17/2009 7:34 AM Jean-Michel Pichavant said...
> Steven D'Aprano wrote:
>> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>>
>>
>> Given three result codes, where 0 means "no error" and an arbitrary non-
>> zero integer means some error, it is simple and easy to write:
>>
>> failed = result_1 or result_2 or result_3
>>
>> The equivalent:
>>
>> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
>> # or if you prefer:
>> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>>
>>   
> [snip]
> 
> This is, I guess, where we disagree. I find the second proposal less 
> error prone, and universally understandable unlike the first one. It may 
> be verbose, it may look even lame to some people, but in the end this is 
> perfectly reliable, because you manipulate only False or True within the 
> boolean operations.
> 
> The first form does not clearly show what is the failed criteria. It 
> just happens by coincidence 

No -- it happens by design because the premise is 'where 0 means "no 
error" and an arbitrary non-zero integer means some error'.

> that in this case the failed criteria 
> matches the Nothingness of result_1, result_2, result_3. What if results 
> may be 'OK' or 'KO'.

Which by definition won't happen for the example cited...

> 
> failed = result_1 or result_2 or result_3
> won't work.

... so you certainly wouldn't write a test that couldn't properly 
determine success or failure.

> 
> failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is 
> lame but reliable.

In this case I'd write something that meets the specs of the problem 
your addressing...

failed = 'KO' in (result_1,result_2,result_3)

Emile




From nohics at gmail.com  Fri Jul 17 12:59:47 2009
From: nohics at gmail.com (nohics nohics)
Date: Fri, 17 Jul 2009 17:59:47 +0100
Subject: Regular exprssion for IRC messages
Message-ID: <e4de9e30907170959y4fcae9d3v8e26d9fd94e76f4f@mail.gmail.com>

Hello,

When an IRC client receive a messages, this message in in a special format
defined here: Message format in pseudo
BNF<http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1>(
http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1 ).

For example we can have:

:MyNickName!n=MyUserName at 41.238.129.121 JOIN :#AnIrcChannel
:MyNickName!n=MyUserName at 41.238.129.121 PRIVMSG #AnIrcChannel :Hello here
:MyNickName!n=MyUserName at 41.238.129.121 NICK :TheNewNickName
:holmes.freenode.net 372 UnNickName :- a message here ...

I want to transforme the message format defined in the irc protocole in the
last link, to a regular expression to get the nickname, the username, the
host, the commad, it's arguments if exist, and the message after ":"

I'm programming in python and I have tried this regular expression:

^(:(\w+)(![^ \r\n]+)?(\@[^ \r\n]+)? )?([a-zA-Z]+|\d\d\d)(( [^: \r\n][^
\r\n]*)+)( :[^\r\n]*)?

Python code:

nicknamePattern = re.compile(r'^(:(\w+)(![^ \r\n]+)?(\@[^ \r\n]+)?
)?([a-zA-Z]+|\d\d\d)(( [^: \r\n][^ \r\n]*)+)( :[^\r\n]*)?')
matches = nicknamePattern.search(data)
if matches != None:  print matches.groups()

But it doesn't seems to work all the time. So can you help me to make the
correct regular expression please ?

You can see some example of messages working or not with this pattren (when
I try to connect to an irc server):
http://www.developpez.net/forums/d779736/php/langage/regex/format-message-pseudo-bnf-expression-reguliere/#post4494010
Thanks.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/1bd7667f/attachment.html>

From python.list at tim.thechases.com  Fri Jul 17 13:11:49 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 17 Jul 2009 12:11:49 -0500
Subject: Question regarding style/design..
In-Reply-To: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
Message-ID: <4A60B0D5.6030806@tim.thechases.com>

> Sometimes I see relatively small application, generally task scripts,
> written as essentially a list of statements. Other times, I see them neatly
> divided into functions and then the "if __name__ == '__main__':" convention.
> Is there a preference? Is there an... application scope such that the
> preference shifts from the former to the latter? I understand the use of the
> __name__ == 'main' convention for building unit tests, but I'm mixed on
> using it in scripts/small applications.

This may circle around to the "is Python a scripting language" 
bruhaha a while back.  I tend to skip the __name__ == '__main__' 
in what I'd consider scripts (one-file hacks to solve an 
immediate problem, often disposable or one-use wonders).  However 
for non-scripts (which I'd define as code that has more than one 
source-code file I've written or that I'd have to maintain) and 
for modules, I tend to put in the __name__ guard.

-tkc






From aurora00 at gmail.com  Fri Jul 17 13:15:59 2009
From: aurora00 at gmail.com (Wai Yip)
Date: Fri, 17 Jul 2009 10:15:59 -0700 (PDT)
Subject: ctype performance benchmark
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
	<4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>
Message-ID: <48c15bac-8af2-472d-9bc0-1f19c4bf29cb@g7g2000prg.googlegroups.com>

I started with ctypes because it is the battery included with the
Python standard library. My code is very fluid and I'm looking for
easy opportunity to optimize it. One example is to find the longest
common prefix among two strings. Right now I am comparing it character
by character with pure Python. It seems like an ideal low hanging
fruit. With ctype I can rewriting a few lines of Python into a few
lines of C. All the tools are available and no third party library is
needed.

It turned out the performance fail to match pure Python. This function
is called million of times in an inner loop. The overhead overwhelm
any performance gain with C. Eventually I have found success grouping
the data into larger chunk for each API call. This is what I
originally planned to do anyway. I am only sharing my experience here
that doing fine grained ctype function call has its limitation.

I have looked into Pyrex before and I was quite confused by the fusion
of C and Python langauage. Perhaps it is time for me to give it a
second look. I just heard of Cython now and it also look interesting.
I think it is helpful for both project to articulate more clearly what
they are, how they achieve the performance gain and to give more
guidance on good use cases. On the other hand, perhaps it is just me
are confused because I don't know enough of the Python internal.

Wai Yip


From mydevforums at gmail.com  Fri Jul 17 13:17:19 2009
From: mydevforums at gmail.com (IronyOfLife)
Date: Fri, 17 Jul 2009 10:17:19 -0700 (PDT)
Subject: Installing python-gnutls on Windows
Message-ID: <58825f8b-9665-4a3d-9f0a-7bb559ae195e@p23g2000vbl.googlegroups.com>

Hi,

I'm new to python and would like to request your help installing
python-gnutls on windows. Are there binaries available which can be
installed ?

Looks like the setup.py file which came with the package is for
Debian. I tried modifying it for windows but am still getting errors.

get_options() is not getting the include directories and libraries so
I harcoded the include directories. I'm getting the following error
now:
//-----------------------------------------------------------------------------------
C:\Development\python\python-gnutls-1.1.8>python setup.py build --
compiler=mingw32
running build
running build_py
running build_ext
building 'gnutls.library._gnutls_init' extension
Traceback (most recent call last):
  File "setup.py", line 86, in <module>
    libraries='-lgnutls -lgnutls-extra')])
  File "C:\Python26\lib\distutils\core.py", line 152, in setup
    dist.run_commands()
  File "C:\Python26\lib\distutils\dist.py", line 975, in run_commands
    self.run_command(cmd)

  ....

  File "C:\Python26\lib\distutils\command\build_ext.py", line 471, in
build_exte
nsions
    self.build_extension(ext)

  ...

    depends=ext.depends)
  File "C:\Python26\lib\distutils\ccompiler.py", line 689, in compile
    depends, extra_postargs)
  File "C:\Python26\lib\distutils\ccompiler.py", line 363, in
_setup_compile
    "'include_dirs' (if supplied) must be a list of strings"
TypeError: 'include_dirs' (if supplied) must be a list of strings
//-------------------------------------------------------------------------------------

I would really appreciate your help

Thanks

Ramg


From lodmod.dod at gmail.com  Fri Jul 17 13:20:43 2009
From: lodmod.dod at gmail.com (LoD MoD)
Date: Fri, 17 Jul 2009 10:20:43 -0700
Subject: getopt code NameError exception on logTail.py
Message-ID: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>

I am having trouble extending my option parsing.

Any help is appreciated:


import sys

import getopt

import time


def tail(file):

    while 1:

        where = file.tell()

        line = file.readline()

        if not line:

            time.sleep(1)

            file.seek(where)

        else:

            print line, # already has newline


def main():



    # parse command line options

    try:

        opts, args = getopt.getopt(sys.argv[1:], "hf:", ["help", "filename="
])

    except getopt.error, msg:

        print msg

        print "for help use --help"

        sys.exit(2)

    # process options

    for o, a in opts:

        if o in ("-h", "--help"):

            print __doc__

            sys.exit(0)

        if o in ("-f", "--filename"):

            print "Parsing F argument"

            file = open(filename, 'r')

            print file






    # process arguments

    for arg in args:

        process(arg) # process() is defined elsewhere


if __name__ == "__main__":

    main()

Yields this error:

localhost:src gsery$ python logTail.py  /var/log/system.log
Traceback (most recent call last):
  File "logTail.py", line 52, in <module>
    main()
  File "logTail.py", line 49, in main
    process(arg) # process() is defined elsewhere
NameError: global name 'process' is not defined
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/ef10e2b8/attachment.html>

From mrabarnett at mrabarnett.plus.com  Fri Jul 17 13:24:42 2009
From: mrabarnett at mrabarnett.plus.com (Matthew Barnett)
Date: Fri, 17 Jul 2009 18:24:42 +0100
Subject: Einstein summation notation
In-Reply-To: <02708ac8$0$5185$c3e8da3@news.astraweb.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>	<mailman.3284.1247843327.8015.python-list@python.org>
	<02708ac8$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A60B3DA.7010506@mrabarnett.plus.com>

Steven D'Aprano wrote:
> On Fri, 17 Jul 2009 16:09:03 +0100, MRAB wrote:
> 
>> Python did always have True and False.

Oops! I meant "didn't", of course.
> 
> $ python1.5
> Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
> 4.1.2-27)] on linux2
> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>> True, False
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
> NameError: True
> 


From phily05 at gmail.com  Fri Jul 17 13:28:13 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 10:28:13 -0700 (PDT)
Subject: Propagate import for all modules in a package.
Message-ID: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>

I'm really new to Python and I am absolutely stumped trying to figure
this out. I have searched plenty, but I am either searching for the
wrong keywords or this isn't possible.

What I want to do is have one import be global for the entire package.
Here is an example...

<package>
  __init__.py
  module1.py
  module2.py
  ...
  moduleN.py

I was thinking that I could just, for example, 'from datetime import
datetime' in __init__.py and have the ability to use 'datetime'
anywhere in any of the modules in 'package'.

This didn't work for me. Did I just do something wrong? Is what I am
trying to do possible?

Thanks in advance.


From Scott.Daniels at Acm.Org  Fri Jul 17 13:37:25 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 17 Jul 2009 10:37:25 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
In-Reply-To: <mailman.3258.1247801202.8015.python-list@python.org>
References: <24509879.post@talk.nabble.com>	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>	<24510222.post@talk.nabble.com>	<4a5ed587$0$1627$742ec2ed@news.sonic.net>	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>	<24522412.post@talk.nabble.com>
	<m2ws68th6f.fsf@cs.uu.nl>	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<mailman.3258.1247801202.8015.python-list@python.org>
Message-ID: <gsKdncY9AMiQKP3XnZ2dnUVZ_hudnZ2d@pdx.net>

akhil1988 wrote:
<mis-ordered reply, bits shown below>>
> Nobody-38 wrote:
>> On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:
...
>>>> In Python 3 you can't decode strings because they are Unicode strings
>>>> and it doesn't make sense to decode a Unicode string. You can only
>>>> decode encoded things which are byte strings. So you are mixing up byte
>>>> strings and Unicode strings.
>>> ... I read a byte string from sys.stdin which needs to converted to unicode
>>> string for further processing.
>> In 3.x, sys.stdin (stdout, stderr) are text streams, which means that they
>> read and write Unicode strings, not byte strings.
>>
>>> I cannot just remove the decode statement and proceed?
>>> This is it what it looks like:
>>>     for line in sys.stdin:
>>>         line = line.decode('utf-8').strip()
>>>         if line == '<page>': #do something here
>>>         ....
>>> If I remove the decode statement, line == '<page>' never gets true. 
>> Did you inadvertently remove the strip() as well?
> ... unintentionally I removed strip()....
> I get this error now:
>  File "./temp.py", line 488, in <module>
>     main()
>   File "./temp.py", line 475, in main
>     for line in sys.stdin:
>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>     (result, consumed) = self._buffer_decode(data, self.errors, final)
> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
> data

(1) Do not top post.
(2) Try to fully understand the problem and proposed solution, rather
     than trying to get people to tell you just enough to get your code
     going.
(3) The only way sys.stdin can possibly return unicode is to do some
     decoding of its own.  your job is to make sure it uses the correct
     decoding.  So, if you know your source is always utf-8, try
     something like:

     import sys
     import io

     sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding='utf8')

     for line in sys.stdin:
         line = line.strip()
         if line == '<page>':
             #do something here
         ....

--Scott David Daniels
Scott.Daniels at Acm.Org


From robert.kern at gmail.com  Fri Jul 17 13:45:44 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 17 Jul 2009 12:45:44 -0500
Subject: Question regarding style/design..
In-Reply-To: <4A60B0D5.6030806@tim.thechases.com>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
	<4A60B0D5.6030806@tim.thechases.com>
Message-ID: <h3qdc9$mdc$1@ger.gmane.org>

On 2009-07-17 12:11, Tim Chase wrote:
>> Sometimes I see relatively small application, generally task scripts,
>> written as essentially a list of statements. Other times, I see them
>> neatly
>> divided into functions and then the "if __name__ == '__main__':"
>> convention.
>> Is there a preference? Is there an... application scope such that the
>> preference shifts from the former to the latter? I understand the use
>> of the
>> __name__ == 'main' convention for building unit tests, but I'm mixed on
>> using it in scripts/small applications.
>
> This may circle around to the "is Python a scripting language" bruhaha a
> while back. I tend to skip the __name__ == '__main__' in what I'd
> consider scripts (one-file hacks to solve an immediate problem, often
> disposable or one-use wonders). However for non-scripts (which I'd
> define as code that has more than one source-code file I've written or
> that I'd have to maintain) and for modules, I tend to put in the
> __name__ guard.

I definitely suggest always using the __name__ guard no matter what. Habits are 
important, and it's usually more of a waste of time trying to determine if you 
are writing a "script" or a "program" than it is to just write the clause all 
the time. One of the ex-DivMod guys (Glyph?) has a good blog post on the subject 
of writing docstrings and the Suzuki Method of violin; however, I cannot find 
it. With a good programmer's editor that can do macros or "snippets", this 
particular habit can be basically cost-free.

There are also technical limitations to be aware of. Even if you don't think you 
will ever import the script, other tools might. For example, on Windows, 
multiprocessing needs to import the main module of the parent process in order 
to do some of its operations. If you do not have a __name__ guard, you will go 
into an infinite regress as your subprocesses execute the main code and create 
subsubprocesses until you finally manage to kill them all. Extra fun if it is a 
GUI and you have to click all of the windows closed.

Don't waste half a day trying to figure out why your script mysteriously doesn't 
work. Learn from my mistakes. :-)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From deets at nospam.web.de  Fri Jul 17 13:52:30 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 17 Jul 2009 19:52:30 +0200
Subject: Propagate import for all modules in a package.
In-Reply-To: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
Message-ID: <7cbs2uF275m7mU1@mid.uni-berlin.de>

Phil schrieb:
> I'm really new to Python and I am absolutely stumped trying to figure
> this out. I have searched plenty, but I am either searching for the
> wrong keywords or this isn't possible.
> 
> What I want to do is have one import be global for the entire package.
> Here is an example...
> 
> <package>
>   __init__.py
>   module1.py
>   module2.py
>   ...
>   moduleN.py
> 
> I was thinking that I could just, for example, 'from datetime import
> datetime' in __init__.py and have the ability to use 'datetime'
> anywhere in any of the modules in 'package'.
> 
> This didn't work for me. Did I just do something wrong? Is what I am
> trying to do possible?

Each module has it's own namespace, there is no real global one. So 
there is no obvious and recommended way to do what you want.

You can do it through, by stuffing names into the __builtins__-module, 
which acts as "namespace of last resort"


from datetime import datetime
__builtins__['datetime'] = datetime

However, this is strongly discouraged - you can easily get 
name-conflicts, and undefined behavior in your modules if you rely on this.

Diez


From zaki.rahaman at gmail.com  Fri Jul 17 13:58:20 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 10:58:20 -0700 (PDT)
Subject: Generator Expressions and CSV
Message-ID: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>

Hey all,

I'm really new to Python and this may seem like a really dumb
question, but basically, I wrote a script to do the following, however
the processing time/memory usage is not what I'd like it to be. Any
suggestions?


Outline:
1. Read tab delim files from a directory, files are of 3 types:
install, update, and q. All 3 types contain ID values that are the
only part of interest.
2. Using set() and set.add(), generate a list of unique IDs from
install and update files.
3. Using the set created in (2), check the q files to see if there are
matches for IDs. Keep all matches, and add any non matches (which only
occur once in the q file) to a queue of lines to be removed from teh q
files.
4. Remove the lines in the q for each file. (I haven't quite written
the code for this, but I was going to implement this using csv.writer
and rewriting all the lines in the file except for the ones in the
removal queue).

Now, I've tried running this and it takes much longer than I'd like. I
was wondering if there might be a better way to do things (I thought
generator expressions might be a good way to attack this problem, as
you could generate the set, and then check to see if there's a match,
and write each line that way).




From python at mrabarnett.plus.com  Fri Jul 17 13:59:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 18:59:09 +0100
Subject: Find first matching substring
In-Reply-To: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>
References: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>
Message-ID: <4A60BBED.7040501@mrabarnett.plus.com>

Eloff wrote:
 > Almost every time I've had to do parsing of text over the last 5 years
 > I've needed this function:
 >
 > def find_first(s, subs, start=None, end=None):
 >     results = [s.find(sub, start, end) for sub in subs]
 >     results = [r for r in results if r != -1]
 >     if results:
 >         return min(results)
 >
 >     return -1
 >
 > It finds the first matching substring in the target string, if there
 > is more than one match, it returns the position of the match that
 > occurs at the lowest index in the string.
 >
One possible optimisation for your code is to note that if you find that
one of the substrings starts at a certain position then you're not
interested in any subsequent substring which might start at or after
that position, so you could reduce the search space for each substring
found.

> Has anyone else had problems where they could have applied this 
> function?
> 
> It seems to me that python's find (and rfind, index, rindex) could be
>  modified (the same way that startswith and endswith have been) to 
> behave this way if a tuple were passed. Do other's agree that this 
> would be desirable?
> 
Possibly. I think that allowing a tuple in the partition and rpartition
methods might also be useful.



From marduk at letterboxes.org  Fri Jul 17 13:59:39 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Fri, 17 Jul 2009 13:59:39 -0400
Subject: Propagate import for all modules in a package.
In-Reply-To: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
Message-ID: <1247853579.17425.10.camel@centar>

On Fri, 2009-07-17 at 10:28 -0700, Phil wrote:
> I'm really new to Python and I am absolutely stumped trying to figure
> this out. I have searched plenty, but I am either searching for the
> wrong keywords or this isn't possible.
> 
> What I want to do is have one import be global for the entire package.
> Here is an example...
> 
> <package>
>   __init__.py
>   module1.py
>   module2.py
>   ...
>   moduleN.py
> 
> I was thinking that I could just, for example, 'from datetime import
> datetime' in __init__.py and have the ability to use 'datetime'
> anywhere in any of the modules in 'package'.
> 
> This didn't work for me. Did I just do something wrong? Is what I am
> trying to do possible?
> 

That's not how packages (were designed to) work.  A package is basically
a namespace.  It doesn't do anything special outside of providing a
namespace for common modules.  There are some special features (e.g.
__init__.py which is basically the "body" of the package and '__all__'
which handles wildcard imports of a package) but other than that it's
just a namespace.



From python.list at tim.thechases.com  Fri Jul 17 14:01:44 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 17 Jul 2009 13:01:44 -0500
Subject: Question regarding style/design..
In-Reply-To: <h3qdc9$mdc$1@ger.gmane.org>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>	<4A60B0D5.6030806@tim.thechases.com>
	<h3qdc9$mdc$1@ger.gmane.org>
Message-ID: <4A60BC88.2070703@tim.thechases.com>

Robert Kern wrote:
[sage advice snipped]
> Don't waste half a day trying to figure out why your script
> mysteriously doesn't work. Learn from my mistakes. :-)

I find that's the best type of mistake to learn from:  other
people's ;-)


-tkc


From hannarosie at gmail.com  Fri Jul 17 14:06:27 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Fri, 17 Jul 2009 11:06:27 -0700
Subject: Writing a single list of numbers to a .m (matlab) file
Message-ID: <564970db0907171106q2be0852dg7209a4177f0b265a@mail.gmail.com>

Hi,

I was wondering if I could get some suggestions on how to write a single
list of numbers to a .m file (for matlab) so that I can create a matlab
vector out of the list of numbers from my python program. I have been using
a csv writer to create .m files from lists of lists, but I'm not sure how to
write just a single list to the file. (if I use the same code I've been
using, I get an error: csv.Error sequence expected)

Thanks for the help!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/23a9b4e8/attachment.html>

From python at mrabarnett.plus.com  Fri Jul 17 14:08:16 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 19:08:16 +0100
Subject: getopt code NameError exception on logTail.py
In-Reply-To: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>
References: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>
Message-ID: <4A60BE10.5050905@mrabarnett.plus.com>

LoD MoD wrote:
> I am having trouble extending my option parsing.
> Any help is appreciated:
> 
> import sys
> import getopt
> import time
> 
> def tail(file):
>     while 1:
>         where = file.tell()
>         line = file.readline()
>         if not line:
>             time.sleep(1)
>             file.seek(where)
>         else:
>             print line, # already has newline
> 
> def main():
> 
>     # parse command line options
>     try:
>         opts, args = getopt.getopt(sys.argv[1:], "hf:", ["help", 
> "filename="])
>     except getopt.error, msg:
>         print msg
>         print "for help use --help"
>         sys.exit(2)
>     # process options
>     for o, a in opts:
>         if o in ("-h", "--help"):
>             print __doc__
>             sys.exit(0)
>         if o in ("-f", "--filename"):
>             print "Parsing F argument"
>             file = open(filename, 'r')
>             print file
> 
>         
>             
>     # process arguments
>     for arg in args:
>         process(arg) # process() is defined elsewhere
> 
> if __name__ == "__main__":
>     main()
> 
> Yields this error:
> 
> localhost:src gsery$ python logTail.py  /var/log/system.log
> Traceback (most recent call last):
>   File "logTail.py", line 52, in <module>
>     main()
>   File "logTail.py", line 49, in main
>     process(arg) # process() is defined elsewhere
> NameError: global name 'process' is not defined
> 
The trackback tells you what's wrong: you haven't defined 'process'. The
comment says it's defined elsewhere, but neither I nor Python can see
it! :-)


From emile at fenx.com  Fri Jul 17 14:26:22 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 17 Jul 2009 11:26:22 -0700
Subject: Generator Expressions and CSV
In-Reply-To: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
Message-ID: <h3qfj0$sv3$1@ger.gmane.org>

On 7/17/2009 10:58 AM Zaki said...
<snip>
> Now, I've tried running this and it takes much longer than I'd like. I
> was wondering if there might be a better way to do things 

Suppose, for the sake of argument, that you've written highly efficient 
code.  Then the processing time would already be entirely optimized and 
no improvements possible.  It's running as fast as it can.  We can't help.

On the other hand, maybe you didn't.  In that case, you'll need to 
profile your code to determine where the time is consumed.  At a 
minimum, you'll need to post the slow parts so we can see the 
implementation and suggest improvements.

Emile



From nick at craig-wood.com  Fri Jul 17 14:29:59 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Fri, 17 Jul 2009 13:29:59 -0500
Subject: ctype performance benchmark
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
	<4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>
	<48c15bac-8af2-472d-9bc0-1f19c4bf29cb@g7g2000prg.googlegroups.com>
Message-ID: <slrnh61gce.r2o.nick@irishsea.home.craig-wood.com>

Wai Yip <aurora00 at gmail.com> wrote:
>  I started with ctypes because it is the battery included with the
>  Python standard library. My code is very fluid and I'm looking for
>  easy opportunity to optimize it. One example is to find the longest
>  common prefix among two strings. Right now I am comparing it character
>  by character with pure Python. It seems like an ideal low hanging
>  fruit. With ctype I can rewriting a few lines of Python into a few
>  lines of C. All the tools are available and no third party library is
>  needed.

Yes ctypes is very easy for this and I've used it like this in the
past too.  It makes interfacing C code very easy.

You might consider just writing a plain bit of C code.  If you make a
setup.py too (not hard) then it is very easy to distribute and use on
other platforms.

The Python C API is very easy to use - documentation is extensive.
You need to be very careful with references and the error checking is
boring and tedious!

>  It turned out the performance fail to match pure Python. This function
>  is called million of times in an inner loop. The overhead overwhelm
>  any performance gain with C. Eventually I have found success grouping
>  the data into larger chunk for each API call. This is what I
>  originally planned to do anyway. I am only sharing my experience here
>  that doing fine grained ctype function call has its limitation.

Interesting but not too unexpected - that translation of types is
non-trivial.

>  I have looked into Pyrex before and I was quite confused by the fusion
>  of C and Python langauage. Perhaps it is time for me to give it a
>  second look. I just heard of Cython now and it also look interesting.
>  I think it is helpful for both project to articulate more clearly what
>  they are, how they achieve the performance gain and to give more
>  guidance on good use cases. On the other hand, perhaps it is just me
>  are confused because I don't know enough of the Python internal.

Pyrex evolved/was forked into Cython.

Cython allows you to write a subset of python code that is compiled
into C.  You can also optionally provide some type annotations to get
it to produce better C code at the cost of making your code look less
like python.

I find Cython alternatively brilliant and frustrating!  Sometimes it
works really well, and sometimes I spend hours working out why my
program doesn't compile, or to find out the exact syntax I need to
interface with such and such a library.

I did a C library interfacing project with both ctypes and cython
recently as a comparison.  It came out to be about the same number of
lines of code for both.  I decided to run with the ctypes version as
it was part python.

Here is a short Cython example which interfaces with opendir /
closedir / readdir which python doesn't do natively.  Note the way you
interface with C structures (the real ones are used in the C code -
the annotations just tell cython how to use them).  Note also that
Directory is a class defined in C which I don't think you can't do
with ctypes without a wrapper class.

This compiles into 1320 lines of C, which in turn compile into 11380
bytes of shared object (when stripped).

import cython

cdef extern from "dirent.h":
    struct dirent:
        char d_name[0]
    ctypedef struct DIR
    DIR *opendir(char *name)
    int closedir(DIR *dirp)
    dirent *readdir(DIR *dirp)

cdef extern from "errno.h":
    int errno

cdef extern from "string.h":
    char *strerror(int errnum)

cdef class Directory:
    """Represents an open directory"""

    cdef DIR *handle

    def __init__(self, path):
        self.handle = opendir(path)
        if self.handle is NULL:
            raise OSError(errno, "Failed to open directory: %s" % strerror(errno))

    def readdir(self):
        """Read the next name in the directory"""
        cdef dirent *p
        p = readdir(self.handle)
        if p is NULL:
            return None
        return p.d_name

    def close(self):
        """Close the directory"""
        if self.handle is not NULL:
            closedir(self.handle)
            self.handle = NULL

    def __dealloc__(self):
        self.close()


-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From lodmod.dod at gmail.com  Fri Jul 17 14:32:50 2009
From: lodmod.dod at gmail.com (LoD MoD)
Date: Fri, 17 Jul 2009 11:32:50 -0700
Subject: getopt code NameError exception on logTail.py
In-Reply-To: <4A60BE10.5050905@mrabarnett.plus.com>
References: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>
	<4A60BE10.5050905@mrabarnett.plus.com>
Message-ID: <e8075cdd0907171132m361906fbw97dd20a58c930743@mail.gmail.com>

In this instance the trackback was somewhat unhelpful.There problem was
here:

           file = open(filename, 'r')

should be

           file = open(a, 'r')

args should be passed within the getopt riff

On Fri, Jul 17, 2009 at 11:08 AM, MRAB <python at mrabarnett.plus.com> wrote:

> LoD MoD wrote:
>
>> I am having trouble extending my option parsing.
>> Any help is appreciated:
>>
>> import sys
>> import getopt
>> import time
>>
>> def tail(file):
>>    while 1:
>>        where = file.tell()
>>        line = file.readline()
>>        if not line:
>>            time.sleep(1)
>>            file.seek(where)
>>        else:
>>            print line, # already has newline
>>
>> def main():
>>
>>    # parse command line options
>>    try:
>>        opts, args = getopt.getopt(sys.argv[1:], "hf:", ["help",
>> "filename="])
>>    except getopt.error, msg:
>>        print msg
>>        print "for help use --help"
>>        sys.exit(2)
>>    # process options
>>    for o, a in opts:
>>        if o in ("-h", "--help"):
>>            print __doc__
>>            sys.exit(0)
>>        if o in ("-f", "--filename"):
>>            print "Parsing F argument"
>>            file = open(filename, 'r')
>>            print file
>>
>>                        # process arguments
>>    for arg in args:
>>        process(arg) # process() is defined elsewhere
>>
>> if __name__ == "__main__":
>>    main()
>>
>> Yields this error:
>>
>> localhost:src gsery$ python logTail.py  /var/log/system.log
>> Traceback (most recent call last):
>>  File "logTail.py", line 52, in <module>
>>    main()
>>  File "logTail.py", line 49, in main
>>    process(arg) # process() is defined elsewhere
>> NameError: global name 'process' is not defined
>>
>>  The trackback tells you what's wrong: you haven't defined 'process'. The
> comment says it's defined elsewhere, but neither I nor Python can see
> it! :-)
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/644d3ab1/attachment.html>

From phily05 at gmail.com  Fri Jul 17 14:42:28 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 11:42:28 -0700 (PDT)
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
	<mailman.3300.1247853630.8015.python-list@python.org>
Message-ID: <663ab878-2ba2-45f1-a38e-2cff94a6bb00@k30g2000yqf.googlegroups.com>

Thanks to both of you for the fast and detailed responses. I will just
treat the package for what it is, a namespace.


From phily05 at gmail.com  Fri Jul 17 14:43:49 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 11:43:49 -0700 (PDT)
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
	<mailman.3300.1247853630.8015.python-list@python.org>
Message-ID: <698e45d2-204b-46c0-ab80-8023e4b8ff15@y19g2000yqy.googlegroups.com>

Thanks to both of you for the fast and detailed responses. I will
just
use the package for what it is, a namespace.


From phily05 at gmail.com  Fri Jul 17 14:44:42 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 11:44:42 -0700 (PDT)
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
	<mailman.3300.1247853630.8015.python-list@python.org>
Message-ID: <9314b787-558b-4891-b519-23228c6d8fb7@m11g2000yqh.googlegroups.com>

Thanks to both of you for the fast and detailed responses. I will just
use the package for what it is, a namespace.


From python at mrabarnett.plus.com  Fri Jul 17 14:49:32 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 19:49:32 +0100
Subject: Generator Expressions and CSV
In-Reply-To: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
Message-ID: <4A60C7BC.4080904@mrabarnett.plus.com>

Zaki wrote:
> Hey all,
> 
> I'm really new to Python and this may seem like a really dumb
> question, but basically, I wrote a script to do the following, however
> the processing time/memory usage is not what I'd like it to be. Any
> suggestions?
> 
> 
> Outline:
> 1. Read tab delim files from a directory, files are of 3 types:
> install, update, and q. All 3 types contain ID values that are the
> only part of interest.
> 2. Using set() and set.add(), generate a list of unique IDs from
> install and update files.
> 3. Using the set created in (2), check the q files to see if there are
> matches for IDs. Keep all matches, and add any non matches (which only
> occur once in the q file) to a queue of lines to be removed from teh q
> files.
> 4. Remove the lines in the q for each file. (I haven't quite written
> the code for this, but I was going to implement this using csv.writer
> and rewriting all the lines in the file except for the ones in the
> removal queue).
> 
> Now, I've tried running this and it takes much longer than I'd like. I
> was wondering if there might be a better way to do things (I thought
> generator expressions might be a good way to attack this problem, as
> you could generate the set, and then check to see if there's a match,
> and write each line that way).
> 
Why are you checking and removing lines in 2 steps? Why not copy the
matching lines to a new q file and then replace the old file with the
new one (or, maybe, delete the new q file if no lines were removed)?


From smolds at comcast.net  Fri Jul 17 14:51:11 2009
From: smolds at comcast.net (Stephen M. Olds)
Date: Fri, 17 Jul 2009 11:51:11 -0700
Subject: Mechanize not recognized by py2exe
Message-ID: <4A60C81F.7080707@comcast.net>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/3b4715cc/attachment.html>

From duncan.booth at invalid.invalid  Fri Jul 17 15:49:54 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 17 Jul 2009 19:49:54 GMT
Subject: ctype performance benchmark
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
	<4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>
	<48c15bac-8af2-472d-9bc0-1f19c4bf29cb@g7g2000prg.googlegroups.com>
Message-ID: <Xns9C4BD3E714F90duncanbooth@127.0.0.1>

Wai Yip <aurora00 at gmail.com> wrote:

> I started with ctypes because it is the battery included with the
> Python standard library. My code is very fluid and I'm looking for
> easy opportunity to optimize it. One example is to find the longest
> common prefix among two strings. Right now I am comparing it character
> by character with pure Python. It seems like an ideal low hanging
> fruit. With ctype I can rewriting a few lines of Python into a few
> lines of C. All the tools are available and no third party library is
> needed.

Alternatively you could just use os.path.commonprefix().



From travis+ml-python at subspacefield.org  Fri Jul 17 16:01:41 2009
From: travis+ml-python at subspacefield.org (travis+ml-python at subspacefield.org)
Date: Fri, 17 Jul 2009 15:01:41 -0500
Subject: proposal: add setresuid() system call to python
Message-ID: <20090717200141.GI6065@subspacefield.org>

Hello,

Historically, I have used scripting languages like python for typical
uses, but they tend to not fare very well at system programming; for
close interfacing with the operating system, I'm often forced to use a
language like C.  This is undesirable to me.

I do not think this has to be the case; I see no reason why a
scripting language can't implement more of the system call API, at the
risk of having some OS-dependent modules.  I would actually like to
see more network servers written in scripting languages, as they
neatly avoid buffer overflow and integer overflow issues with no extra
effort.

One BIG roadblock to doing this is when they can't manage to drop
permissions properly.

I am suggesting that the setresuid function be added to python,
perhaps in the OS module, because it has the clearest semantics for
manipulating user ids.  The reason why is best described in the
following paper:

http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf

One argument against this is that it is not specified by POSIX, and
thus might be dismissed as "implementation dependent".

However, as the paper above demonstrates, even though the setuid
system call is defined by POSIX, it already has system-dependent
behavior.  POSIX provides for at least two different behaviors of the
setuid call, and even more if you consider that it leaves what
constitutes "appropriate privileges" up to the OS kernel.

I humbly propose that python implement all the routines necessary to
securely drop privileges, to enable construction of network daemons
that might need to drop privileges from root to some non-root userid
(e.g. mail transfer agents, or POP/IMAP servers).

Furthermore, where there are multiple system calls to achieve this
effect, it should implement the ones with the clearest semantics, and
setresuid fits that bill.  To see what an utter mess the uid-manipulation
routines are in, I refer you once again to this paper, as the situation
is too complicated to describe in this email:

http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf

Opinions?

Best,
Travis
-- 
Obama Nation | My emails do not have attachments; it's a digital signature
that your mail program doesn't understand. | http://www.subspacefield.org/~travis/ 
If you are a spammer, please email john at subspacefield.org to get blacklisted.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 850 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/2a18ffb1/attachment.sig>

From zaki.rahaman at gmail.com  Fri Jul 17 16:08:05 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 13:08:05 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
Message-ID: <71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>

On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Zaki wrote:
> > Hey all,
>
> > I'm really new to Python and this may seem like a really dumb
> > question, but basically, I wrote a script to do the following, however
> > the processing time/memory usage is not what I'd like it to be. Any
> > suggestions?
>
> > Outline:
> > 1. Read tab delim files from a directory, files are of 3 types:
> > install, update, and q. All 3 types contain ID values that are the
> > only part of interest.
> > 2. Using set() and set.add(), generate a list of unique IDs from
> > install and update files.
> > 3. Using the set created in (2), check the q files to see if there are
> > matches for IDs. Keep all matches, and add any non matches (which only
> > occur once in the q file) to a queue of lines to be removed from teh q
> > files.
> > 4. Remove the lines in the q for each file. (I haven't quite written
> > the code for this, but I was going to implement this using csv.writer
> > and rewriting all the lines in the file except for the ones in the
> > removal queue).
>
> > Now, I've tried running this and it takes much longer than I'd like. I
> > was wondering if there might be a better way to do things (I thought
> > generator expressions might be a good way to attack this problem, as
> > you could generate the set, and then check to see if there's a match,
> > and write each line that way).
>
> Why are you checking and removing lines in 2 steps? Why not copy the
> matching lines to a new q file and then replace the old file with the
> new one (or, maybe, delete the new q file if no lines were removed)?

That's what I've done now.

Here is the final code that I have running. It's very much 'hack' type
code and not at all efficient or optimized and any help in optimizing
it would be greatly appreciated.

import csv
import sys
import os
import time

begin = time.time()

#Check minutes elapsed
def timeElapsed():
    current = time.time()
    elapsed = current-begin
    return round(elapsed/60)


#USAGE: python logcleaner.py <input_dir> <output_dir>

inputdir = sys.argv[1]
outputdir = sys.argv[2]

logfilenames = os.listdir(inputdir)



IDs = set() #IDs from update and install logs
foundOnceInQuery = set()
#foundTwiceInQuery = set()
#IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
Queue of IDs to remove from query logs (IDs found only once in query
logs)

#Generate Filename Queues For Install/Update Logs, Query Logs
iNuQ = []
queryQ = []

for filename in logfilenames:
    if filename.startswith("par1.install") or filename.startswith
("par1.update"):
        iNuQ.append(filename)
    elif filename.startswith("par1.query"):
        queryQ.append(filename)

totalfiles = len(iNuQ) + len(queryQ)
print "Total # of Files to be Processed:" , totalfiles
print "Install/Update Logs to be processed:" , len(iNuQ)
print "Query logs to be processed:" , len(queryQ)

#Process install/update queue to generate list of valid IDs
currentfile = 1
for file in iNuQ:
    print "Processing", currentfile, "install/update log out of", len
(iNuQ)
    print timeElapsed()
    reader = csv.reader(open(inputdir+file),delimiter = '\t')
    for row in reader:
        IDs.add(row[2])
    currentfile+=1

print "Finished processing install/update logs"
print "Unique IDs found:" , len(IDs)
print "Total Time Elapsed:", timeElapsed()

currentfile = 1
for file in queryQ:
    print "Processing", currentfile, "query log out of", len(queryQ)
    print timeElapsed()
    reader = csv.reader(open(inputdir+file), delimiter = '\t')
    outputfile = csv.writer(open(outputdir+file), 'w')
    for row in reader:
        if row[2] in IDs:
            ouputfile.writerow(row)
        else:
            if row[2] in foundOnceInQuery:
                foundOnceInQuery.remove(row[2])
                outputfile.writerow(row)
                #IDremovalQ.remove(row[2])
                #foundTwiceInQuery.add(row[2])

            else:
                foundOnceInQuery.add(row[2])
                #IDremovalQ.add(row[2])


    currentfile+=1

print "Finished processing query logs and writing new files"
print "# of Query log entries removed:" , len(foundOnceInQuery)
print "Total Time Elapsed:", timeElapsed()




From jcd at sdf.lonestar.org  Fri Jul 17 16:08:26 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 17 Jul 2009 16:08:26 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <kmy21c.fd3@spenarnc.xs4all.nl>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<kmy21c.fd3@spenarnc.xs4all.nl>
Message-ID: <1247861306.6362.6.camel@aalcdl07>

On Fri, 2009-07-17 at 20:53 +0000, Albert van der Horst wrote:
> Because unlike in algol 68 in python whitespace is relevant,
> we could get by with requiring whitespace:
>         x= -q                       # okay
>         a<b and -a<c and -b < -d    # okay
>         8 ** -2                     # okay

This is actually quite thoroughly untrue.  In python, *indentation* is
significant.  Whitespace (internal to a line) is not.  You can even call
methods like this if you want:

>>> s = 'abc'
>>> s        .     upper()
ABC

Obviously, that's A Bad Idea(tm), but python's parser won't stop you.
The ++ operator gotcha is so minor that I can't remember anyone actually
asking about it on the list (who was actually facing it as a
problem--this thread was started by idle speculation).  Can we not
change the language syntax to address non-issues?

Practicality beats purity, a.k.a. don't you have something better to do?


Cheers,
Cliff





From mabdelkader at gmail.com  Fri Jul 17 16:15:00 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Fri, 17 Jul 2009 16:15:00 -0400
Subject: proposal: add setresuid() system call to python
In-Reply-To: <20090717200141.GI6065@subspacefield.org>
References: <20090717200141.GI6065@subspacefield.org>
Message-ID: <148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>

Why don't you write a python extension module? This is a perfect opportunity
for that.

--
mahmoud mack abdelkader
http://blog.mahmoudimus.com/



On Fri, Jul 17, 2009 at 4:01 PM,
<travis+ml-python at subspacefield.org<travis%2Bml-python at subspacefield.org>
> wrote:

> Hello,
>
> Historically, I have used scripting languages like python for typical
> uses, but they tend to not fare very well at system programming; for
> close interfacing with the operating system, I'm often forced to use a
> language like C.  This is undesirable to me.
>
> I do not think this has to be the case; I see no reason why a
> scripting language can't implement more of the system call API, at the
> risk of having some OS-dependent modules.  I would actually like to
> see more network servers written in scripting languages, as they
> neatly avoid buffer overflow and integer overflow issues with no extra
> effort.
>
> One BIG roadblock to doing this is when they can't manage to drop
> permissions properly.
>
> I am suggesting that the setresuid function be added to python,
> perhaps in the OS module, because it has the clearest semantics for
> manipulating user ids.  The reason why is best described in the
> following paper:
>
> http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf<http://www.eecs.berkeley.edu/%7Edaw/papers/setuid-usenix02.pdf>
>
> One argument against this is that it is not specified by POSIX, and
> thus might be dismissed as "implementation dependent".
>
> However, as the paper above demonstrates, even though the setuid
> system call is defined by POSIX, it already has system-dependent
> behavior.  POSIX provides for at least two different behaviors of the
> setuid call, and even more if you consider that it leaves what
> constitutes "appropriate privileges" up to the OS kernel.
>
> I humbly propose that python implement all the routines necessary to
> securely drop privileges, to enable construction of network daemons
> that might need to drop privileges from root to some non-root userid
> (e.g. mail transfer agents, or POP/IMAP servers).
>
> Furthermore, where there are multiple system calls to achieve this
> effect, it should implement the ones with the clearest semantics, and
> setresuid fits that bill.  To see what an utter mess the uid-manipulation
> routines are in, I refer you once again to this paper, as the situation
> is too complicated to describe in this email:
>
> http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf<http://www.eecs.berkeley.edu/%7Edaw/papers/setuid-usenix02.pdf>
>
> Opinions?
>
> Best,
> Travis
> --
> Obama Nation | My emails do not have attachments; it's a digital signature
> that your mail program doesn't understand. |
> http://www.subspacefield.org/~travis/<http://www.subspacefield.org/%7Etravis/>
> If you are a spammer, please email john at subspacefield.org to get
> blacklisted.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/176d6f43/attachment.html>

From robert.kern at gmail.com  Fri Jul 17 16:15:35 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 17 Jul 2009 15:15:35 -0500
Subject: proposal: add setresuid() system call to python
In-Reply-To: <20090717200141.GI6065@subspacefield.org>
References: <20090717200141.GI6065@subspacefield.org>
Message-ID: <h3qm59$guh$1@ger.gmane.org>

On 2009-07-17 15:01, travis+ml-python at subspacefield.org wrote:
> Hello,
>
> Historically, I have used scripting languages like python for typical
> uses, but they tend to not fare very well at system programming; for
> close interfacing with the operating system, I'm often forced to use a
> language like C.  This is undesirable to me.

You can use ctypes for most of these use cases.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From tjreedy at udel.edu  Fri Jul 17 16:32:51 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 16:32:51 -0400
Subject: turtle dump
In-Reply-To: <h3p5mm$o6s$01$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>	<h3o6hr$mmh$02$1@news.t-online.com>
	<h3obqg$aru$1@ger.gmane.org>	<mailman.3246.1247792169.8015.python-list@python.org>
	<h3p5mm$o6s$01$1@news.t-online.com>
Message-ID: <h3qn5k$jot$1@ger.gmane.org>

Peter Otten wrote:
> Terry Reedy wrote:
>
>> I tried it. Unfortunately, OOo does not open it correctly. It just
>> displays the first three lines of metadate - Title, Creator, Date -- as
>> image text. Photoshop does read the image, and does an ok job of
>> conversion once anti-aliasing is turned off.
> 
> I snatched some code from the module and modified it to save a sample image:

Thank you for the example.

> 
> from turtle import *
> 
> def switchpen():
>     if isdown():
>         pu()
>     else:
>         pd()
> 
> def demo2():
>     """Demo of some new features."""
>     speed(1)
>     st()
>     pensize(3)
>     setheading(towards(0, 0))
>     radius = distance(0, 0)/2.0
>     rt(90)
>     for _ in range(18):
>         switchpen()
>         circle(radius, 10)
>     write("wait a moment...")
>     while undobufferentries():
>         undo()
>     reset()
>     lt(90)
>     colormode(255)
>     laenge = 10
>     pencolor("green")
>     pensize(3)
>     lt(180)
>     for i in range(-2, 16):
>         if i > 0:
>             begin_fill()
>             fillcolor(255-15*i, 0, 15*i)
>         for _ in range(3):
>             fd(laenge)
>             lt(120)
>         laenge += 10
>         lt(15)
>         speed((speed()+1)%12)
>     end_fill()
> 
>     lt(120)
>     pu()
>     fd(70)
>     rt(30)
>     pd()
>     color("red","yellow")
>     speed(0)
>     fill(1)

begin_fill() in 3.x

>     for _ in range(4):
>         circle(50, 90)
>         rt(90)
>         fd(30)
>         rt(90)
>     fill(0)

end_fill() in 3.x

>     lt(90)
>     pu()
>     fd(30)
>     pd()
>     shape("turtle")
> 
>     tri = getturtle()
>     tri.resizemode("auto")
>     turtle = Turtle()
>     turtle.resizemode("auto")
>     turtle.shape("turtle")
>     turtle.reset()
>     turtle.left(90)
>     turtle.speed(0)
>     turtle.up()
>     turtle.goto(280, 40)
>     turtle.lt(30)
>     turtle.down()
>     turtle.speed(6)
>     turtle.color("blue","orange")
>     turtle.pensize(2)
>     tri.speed(6)
>     setheading(towards(turtle))
>     count = 1
>     while tri.distance(turtle) > 4:
>         turtle.fd(3.5)
>         turtle.lt(0.6)
>         tri.setheading(tri.towards(turtle))
>         tri.fd(4)
>         if count % 20 == 0:
>             turtle.stamp()
>             tri.stamp()
>             switchpen()
>         count += 1
>     tri.write("CAUGHT! ", font=("Arial", 16, "bold"), align="right")
> 
> if __name__ == "__main__":
>     demo2()
>     Screen().getcanvas().postscript(file="demo2.eps")
> 
> I could successfully insert the picture into Writer.

Whereas I still get just three lines of metadata.
The size of my demo2.eps is given as 65,628 bytes.
'Size on disk is given as a bit more but I presume that counts to the 
end of the last 4k block.

> I'm on Kubuntu 9.04 with Python 2.6.2 and OpenOffice 3.0.1.

WinXP with updates, Python 3.1, and OO 3.1.0

So either tk 8.5(?) on windows is producing something different or OO3.1 
  on windows is reading differently. If your file size is different, 
could you email it so I could try to import it here?

> But still, turtle is an educational tool, its main advantage is that it can 
> show beginners how the image is generated.

It is also available with Python as installed. And I want to do simple 
animations (of algoritms) as well as static pictures.

> If you want to generate high-quality graphics easily you need different 
> primitives.
> 
> http://cairographics.org
> 
> has Python bindings, but I don't know if it's available on Windows.

Effectively not, as far as I can tell. PyCairo appears to be *nix and 
require later binaries than those available from gtk site referenced 
from cairo site.

Terry Jan Reedy



From tjreedy at udel.edu  Fri Jul 17 16:36:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 16:36:17 -0400
Subject: turtle dump
In-Reply-To: <364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com>	<mailman.3245.1247785636.8015.python-list@python.org>
	<364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>
Message-ID: <h3qnc2$kb0$1@ger.gmane.org>

alex23 wrote:

> The help in iPython says the same, but also mentions that it's a
> dynamically generated function, so it may not be picking up the
> docstring that way. turtle.ScrolledCanvas.postscript is similarly
> terse, but you can find more info in turtle.Canvas.postscript:
> 
>   Print the contents of the canvas to a postscript
>   file. Valid options: colormap, colormode, file, fontmap,
>   height, pageanchor, pageheight, pagewidth, pagex, pagey,
>   rotate, witdh, x, y.

How, exactly, did you get that list?

tjr



From piet at cs.uu.nl  Fri Jul 17 16:48:37 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 22:48:37 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
	<mailman.3261.1247811927.8015.python-list@python.org>
	<m2eisfu2m0.fsf@cs.uu.nl>
	<mailman.3285.1247843986.8015.python-list@python.org>
Message-ID: <m2ws67rq6y.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Piet van Oostrum wrote:
>>>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>>> 
>>> 
>>> 
>GR> I have a 1-1 relation, I have a thread reading msgs from a network socket
>GR> and a method waiting for an answer to arrive (see my thread
>GR> "Threading.Condition problem"). I would like to be able to have a timeout
>GR> as to not block forever, so the idea is to check if I returned because of a
>GR> timeout or not.
>>>> 
>>> 
>>> So that case is easy I think. After the wait just check if the answer
>>> has arrived.
>>> 
>GR> The problem is other answers could arrive that are not the one I
>GR> want. Maybe I could check if I got the answer, if not then check
>GR> how much time has elapsed, and if it's grater or equal to the
>GR> timeout consider it a timeout. I still think a return value would
>GR> be better though.

The wait will not get a return value in Python. There was an issue
posted in the tracker to request this in 2005. Recently (after 4 years)
it was rejected by the BDFL. See http://bugs.python.org/issue1175933

OK, your use case might be a bit more difficult, but I still think it
can be solved without a return value. I can't tell exactly how because
of lack of information.

So (as I already mentioned in one of my previous messages) being
notified doesn't imply that everything is OK. Now suppose that your CV
is notified one microsecond before it would time out but the required
answer did not arrive. What's the difference with a real timeout except
for that microsecond?

Reimplementing Condition yourself is not to be recommended I think.
Using these synchronisation primitives is hard enough let alone
implementing them. 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From albert at spenarnc.xs4all.nl  Fri Jul 17 16:53:36 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 17 Jul 2009 20:53:36 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
Message-ID: <kmy21c.fd3@spenarnc.xs4all.nl>

In article <mailman.2664.1246857607.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
><steve at remove-this-cybersource.com.au> escribi?:
>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>
>>> I wonder how many people have been tripped up by the fact that
>>>
>>>     ++n
>>>
>>> and
>>>
>>>     --n
>>>
>>> fail silently for numeric-valued n.
>>
>> What do you mean, "fail silently"? They do exactly what you should
>> expect:
>>>>> ++5  # positive of a positive number is positive
>>
>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>> that are buggy, not Python.
>
>Well, those expectations are taken seriously when new features are
>introduced into the language - and sometimes the feature is dismissed just
>because it would be confusing for some.
>If a += 1 works, expecting ++a to have the same meaning is very reasonable
>(for those coming from languages with a ++ operator, like C or Java) -
>more when ++a is a perfectly valid expression.
>If this issue isn't listed under the various "Python gotchas" articles, it
>should...

In algol 68 there was one thing strictly forbidden: putting two
operators behind each other:
x :=  y** -b .comment  must be x := y**(-b) .comment

This is quite a sensible rule, especially when, like in Python,
two special characters can be run together to denote a different
operator.
Examples abound :   +:=  **
A consequence is that  'a*-b'
would be illegal. It would become 'a*(-b)'
Worse is that x=-q would be illegal.

Because unlike in algol 68 in python whitespace is relevant,
we could get by with requiring whitespace:
        x= -q                       # okay
        a<b and -a<c and -b < -d    # okay
        8 ** -2                     # okay

Once a c-addict is forced to write
   + +a
she will realize that probably the operator is + is applied to
+a, and that a ++ has no meaning.

>--
>Gabriel Genellina

Groetjes Albert


--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From clp2 at rebertia.com  Fri Jul 17 16:55:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 17 Jul 2009 13:55:20 -0700
Subject: Writing a single list of numbers to a .m (matlab) file
In-Reply-To: <564970db0907171106q2be0852dg7209a4177f0b265a@mail.gmail.com>
References: <564970db0907171106q2be0852dg7209a4177f0b265a@mail.gmail.com>
Message-ID: <50697b2c0907171355q76f7c538le319b2240bb4210e@mail.gmail.com>

On Fri, Jul 17, 2009 at 11:06 AM, Hanna Michelsen<hannarosie at gmail.com> wrote:
> Hi,
>
> I was wondering if I could get some suggestions on how to write a single
> list of numbers to a .m file (for matlab) so that I can create a matlab
> vector out of the list of numbers from my python program. I have been using
> a csv writer to create .m files from lists of lists, but I'm not sure how to
> write just a single list to the file. (if I use the same code I've been
> using, I get an error: csv.Error sequence expected)

You didn't provide any code, but since csv is probably overkill anyway:

m_file.write("[" + " ".join(str(num) for num in numbers) + "]\n")

Cheers,
Chris
-- 
http://blog.rebertia.com


From python at mrabarnett.plus.com  Fri Jul 17 16:57:46 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 21:57:46 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <1247861306.6362.6.camel@aalcdl07>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<kmy21c.fd3@spenarnc.xs4all.nl>
	<1247861306.6362.6.camel@aalcdl07>
Message-ID: <4A60E5CA.1000106@mrabarnett.plus.com>

J. Cliff Dyer wrote:
> On Fri, 2009-07-17 at 20:53 +0000, Albert van der Horst wrote:
>> Because unlike in algol 68 in python whitespace is relevant,
>> we could get by with requiring whitespace:
>>         x= -q                       # okay
>>         a<b and -a<c and -b < -d    # okay
>>         8 ** -2                     # okay
> 
> This is actually quite thoroughly untrue.  In python, *indentation* is
> significant.  Whitespace (internal to a line) is not.
[snip]
Whitespace (internal to a line) _mostly_ is not. It's not allowed within
names, and it is needed in the second example above, before the 'and's.


From exarkun at divmod.com  Fri Jul 17 16:59:53 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Fri, 17 Jul 2009 16:59:53 -0400
Subject: proposal: add setresuid() system call to python
In-Reply-To: <20090717200141.GI6065@subspacefield.org>
Message-ID: <20090717205953.2543.1223422516.divmod.quotient.3129@henry.divmod.com>

On Fri, 17 Jul 2009 15:01:41 -0500, travis+ml-python at subspacefield.org wrote:
>Hello,
>
> [snip]
>
>I am suggesting that the setresuid function be added to python,
>perhaps in the OS module, because it has the clearest semantics for
>manipulating user ids.  The reason why is best described in the
>following paper:

Yes, it'd be good for Python to expose setresuid.  The best course of
action is to file a ticket in the issue tracker.  Things will be sped
along if you also attach a patch implementing the change. :)

Jean-Paul


From piet at cs.uu.nl  Fri Jul 17 16:59:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 22:59:54 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
	<mailman.3261.1247811927.8015.python-list@python.org>
	<m2eisfu2m0.fsf@cs.uu.nl>
	<mailman.3285.1247843986.8015.python-list@python.org>
	<m2ws67rq6y.fsf@cs.uu.nl>
Message-ID: <m2skgvrpo5.fsf@cs.uu.nl>

I should add that *if the wait times out* it still could be the case
that your answer has arrived but that the notify occured a microsecond
after the timeout. So knowing if the timeout occurred really doesn't
tell you much. It's just a way to prevent infinite waiting.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From tjreedy at udel.edu  Fri Jul 17 16:59:59 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 16:59:59 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <SfY7m.5466$875.1940@newsfe20.ams2>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
Message-ID: <h3qoof$n9v$1@ger.gmane.org>

Sion Arrowsmith wrote:
> Jack Diederich  <jackdied at gmail.com> wrote:
>> It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>> dicts also raise an error if you try to LT them.
> 
> Since when?
> 
> Python 2.5.2 (r252:60911, Jan  4 2009, 17:40:26)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> d1 = dict((str(i), i) for i in range (10))
>>>> d2 = dict((str(i), i) for i in range (20))
>>>> d1 < d2
> True

Try reversing the definitions of d1 and d2. The dicts are probably being 
compared by id (address), which is the 2.x CPython default.

> (Don't have a 2.6 or 3 to hand.)

2.6 same. 3.1
 >>> d1,d2 = {},{}
 >>> d1 < d2
Traceback (most recent call last):
   File "<pyshell#16>", line 1, in <module>
     d1 < d2
TypeError: unorderable types: dict() < dict()



From aahz at pythoncraft.com  Fri Jul 17 17:03:59 2009
From: aahz at pythoncraft.com (Aahz)
Date: 17 Jul 2009 14:03:59 -0700
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>
	<h3nusa$pcb$1@panix3.panix.com>
	<94c1adf3-a25d-4ae5-9f38-7ca8680d022d@b14g2000yqd.googlegroups.com>
Message-ID: <h3qovv$ivk$1@panix3.panix.com>

In article <94c1adf3-a25d-4ae5-9f38-7ca8680d022d at b14g2000yqd.googlegroups.com>,
hartley  <hartley79 at gmail.com> wrote:
>On Jul 16, 9:26=A0pm, a... at pythoncraft.com (Aahz) wrote:
>> In article <0afc5c4d-1af5-4d0e-9442-26b51b12e... at m11g2000yqh.googlegroups=
>.com>,
>> hartley =A0<hartle... at gmail.com> wrote:
>>>
>>>If you had loosened up on the sarcasm I would probably have read what
>>>you wrote more thoroughly instead of just skimming through it. Thanks
>>>for the help, but you should seriously consider doing something with
>>>your patronizing attitude.
>>
>> http://www.mikeash.com/getting_answers.htmlhttp://www.catb.org/~esr/faqs/=
>smart-questions.html
>
>From "http://www.mikeash.com/getting_answers.html":
>
>How To Ask Questions The Smart Way is pretty condescending, especially
>if you already feel insulted by somebody telling you that you need
>help asking questions. If you're pointed at a guide with a filename of
>smart-questions, that means this person thinks you have stupid
>questions, and who needs that?
>
>Cheers mate :)

Not really.  Feel free to chide people trying to help you, eventually
people won't care.  <shrug>
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From tjreedy at udel.edu  Fri Jul 17 17:09:40 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 17:09:40 -0400
Subject: 'del' function for Dictionary
In-Reply-To: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
References: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
Message-ID: <h3qpal$psp$1@ger.gmane.org>

mayank gupta wrote:
> Hi all,
> 
> I wanted to know whether there is a more efficient way to delete an 
> entry from a dictionary (instead of using the 'del' function), because 
> after analyzing the time taken by the code, it seems to me that the 
> 'del' function takes most of the time.

That is hard to imagine.

del ob[sub]

has the same effect as

ob.__delitem__(sub)

but I suspect this would take longer since it requires a runtime 
attribute lookup and Python level function call.  So I am pretty sure 
the answer is 'no'.

tjr



From python at mrabarnett.plus.com  Fri Jul 17 17:31:30 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 22:31:30 +0100
Subject: Generator Expressions and CSV
In-Reply-To: <71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
Message-ID: <4A60EDB2.5050202@mrabarnett.plus.com>

Zaki wrote:
> On Jul 17, 2:49 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> Zaki wrote:
>>> Hey all,
>>> I'm really new to Python and this may seem like a really dumb
>>> question, but basically, I wrote a script to do the following, however
>>> the processing time/memory usage is not what I'd like it to be. Any
>>> suggestions?
>>> Outline:
>>> 1. Read tab delim files from a directory, files are of 3 types:
>>> install, update, and q. All 3 types contain ID values that are the
>>> only part of interest.
>>> 2. Using set() and set.add(), generate a list of unique IDs from
>>> install and update files.
>>> 3. Using the set created in (2), check the q files to see if there are
>>> matches for IDs. Keep all matches, and add any non matches (which only
>>> occur once in the q file) to a queue of lines to be removed from teh q
>>> files.
>>> 4. Remove the lines in the q for each file. (I haven't quite written
>>> the code for this, but I was going to implement this using csv.writer
>>> and rewriting all the lines in the file except for the ones in the
>>> removal queue).
>>> Now, I've tried running this and it takes much longer than I'd like. I
>>> was wondering if there might be a better way to do things (I thought
>>> generator expressions might be a good way to attack this problem, as
>>> you could generate the set, and then check to see if there's a match,
>>> and write each line that way).
>> Why are you checking and removing lines in 2 steps? Why not copy the
>> matching lines to a new q file and then replace the old file with the
>> new one (or, maybe, delete the new q file if no lines were removed)?
> 
> That's what I've done now.
> 
> Here is the final code that I have running. It's very much 'hack' type
> code and not at all efficient or optimized and any help in optimizing
> it would be greatly appreciated.
> 
> import csv
> import sys
> import os
> import time
> 
> begin = time.time()
> 
> #Check minutes elapsed
> def timeElapsed():
>     current = time.time()
>     elapsed = current-begin
>     return round(elapsed/60)
> 
> 
> #USAGE: python logcleaner.py <input_dir> <output_dir>
> 
> inputdir = sys.argv[1]
> outputdir = sys.argv[2]
> 
> logfilenames = os.listdir(inputdir)
> 
> 
> 
> IDs = set() #IDs from update and install logs
> foundOnceInQuery = set()
> #foundTwiceInQuery = set()
> #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> Queue of IDs to remove from query logs (IDs found only once in query
> logs)
> 
> #Generate Filename Queues For Install/Update Logs, Query Logs
> iNuQ = []
> queryQ = []
> 
> for filename in logfilenames:
>     if filename.startswith("par1.install") or filename.startswith
> ("par1.update"):
      if filename.startswith(("par1.install", "par1.update")):

>         iNuQ.append(filename)
>     elif filename.startswith("par1.query"):
>         queryQ.append(filename)
> 
> totalfiles = len(iNuQ) + len(queryQ)
> print "Total # of Files to be Processed:" , totalfiles
> print "Install/Update Logs to be processed:" , len(iNuQ)
> print "Query logs to be processed:" , len(queryQ)
> 
> #Process install/update queue to generate list of valid IDs
> currentfile = 1
> for file in iNuQ:
 >     print "Processing", currentfile, "install/update log out of", len
 > (iNuQ)
 >     print timeElapsed()
 >     reader = csv.reader(open(inputdir+file),delimiter = '\t')
 >     for row in reader:
 >         IDs.add(row[2])
 >     currentfile+=1

Best not to call it 'file'; that's a built-in name.

Also you could use 'enumerate', and joining filepaths is safer with
os.path.join().

for currentfile, filename in enumerate(iNuQ, start=1):
     print "Processing", currentfile, "install/update log out of", len(iNuQ)
     print timeElapsed()
     current_path = os.path.join(inputdir, filename)
     reader = csv.reader(open(current_path), delimiter = '\t')
     for row in reader:
         IDs.add(row[2])

> 
> print "Finished processing install/update logs"
> print "Unique IDs found:" , len(IDs)
> print "Total Time Elapsed:", timeElapsed()
> 
> currentfile = 1
> for file in queryQ:

Similar remarks to above ...

>     print "Processing", currentfile, "query log out of", len(queryQ)
>     print timeElapsed()
>     reader = csv.reader(open(inputdir+file), delimiter = '\t')
>     outputfile = csv.writer(open(outputdir+file), 'w')

... and also here.

>     for row in reader:
>         if row[2] in IDs:
>             ouputfile.writerow(row)

Should be 'outputfile'.

>         else:
>             if row[2] in foundOnceInQuery:
>                 foundOnceInQuery.remove(row[2])

You're removing the ID here ...

>                 outputfile.writerow(row)
>                 #IDremovalQ.remove(row[2])
>                 #foundTwiceInQuery.add(row[2])
> 
>             else:
>                 foundOnceInQuery.add(row[2])

... and adding it again here!

>                 #IDremovalQ.add(row[2])
> 
> 
>     currentfile+=1
> 
For safety you should close the files after use.

> print "Finished processing query logs and writing new files"
> print "# of Query log entries removed:" , len(foundOnceInQuery)
> print "Total Time Elapsed:", timeElapsed()
> 
Apart from that, it looks OK.

How big are the q files? If they're not too big and most of the time
you're not removing rows, you could put the output rows into a list and
then create the output file only if rows have been removed, otherwise
just copy the input file, which might be faster.


From emile at fenx.com  Fri Jul 17 17:56:12 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 17 Jul 2009 14:56:12 -0700
Subject: Generator Expressions and CSV
In-Reply-To: <71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
Message-ID: <h3qrse$j2$1@ger.gmane.org>

On 7/17/2009 1:08 PM Zaki said...
> Here is the final code that I have running. It's very much 'hack' type
> code and not at all efficient or optimized and any help in optimizing
> it would be greatly appreciated.

There are some things I'd approach differently , eg I might prefer glob 
to build iNuQ and queryQ [1], and although glob is generally fast, I'm 
not sure it'd be faster.  But overall it looks like most of the time is 
spent in your 'for row in' loops, and as you're reading each file only 
once, and would have to anyway, there's not much that'll improve overall 
timing.  I don't know what csvreader is doing under the covers, but if 
your files are reasonably sized for your system you might try timing 
something that reads in the full file and splits:

for each in filelist:
     for row in open(filelist).readlines():
         if row.split()[2] in ....

-----[1]-----
import glob

iNuQ = glob.glob(os.sep.join(inputdir,"par1.install*")
queryQ = glob.glob(os.sep.join(inputdir,"par1.query*")



Emile



From lie.1296 at gmail.com  Fri Jul 17 17:58:21 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sat, 18 Jul 2009 07:58:21 +1000
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>	<mailman.3275.1247836630.8015.python-list@python.org>	<02707804$0$5185$c3e8da3@news.astraweb.com>	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
Message-ID: <h3qs5u$1cr$1@ger.gmane.org>

Xavier Ho wrote:
> oops, wrong address.
> 
> When will reply-to tag appear on the Python mailing list? =/
> 
> Good idea, Steven and MRAB.
> 
> I changed my code to the following:
> 
> 
>     def nPrime(self, n):
>         "Returns nth prime number, the first one being 2, where n = 0.
> When n = 1, it returns 3."
>         for x in range(n+2):
> 
>             try:
>                 return self.primes[n]
>             except IndexError:
>                 self.next()

If you're looking for speed, you should be aware that a failed
try-clause is quite expensive in python and often (as in this case)
codes using exception can be less readable than the one without since a
program's flow in the case of exception is not linear (the non-linear
execution is useful for quickly breaking out from nests of clauses, but
not necessary in this case).

Semantically, it is also wrong. Not finding the n'th prime in the cache
is not really an exceptional case.

If you insists on using a try-except clause, use it this way:

# untested
def nPrime(self, n):
    try:
        return self.primes[n]
    except IndexError:
        for _ in xrange(len(self.primes), n+1):
            self.next()
        return self.primes[n]



From lodmod.dod at gmail.com  Fri Jul 17 17:58:46 2009
From: lodmod.dod at gmail.com (LoD MoD)
Date: Fri, 17 Jul 2009 14:58:46 -0700
Subject: creating my own logwatch in python
Message-ID: <e8075cdd0907171458g162db8aai9dc5ef6ba49ec886@mail.gmail.com>

I am trying to fabricate a logwatch-type script in Python and I'm having
some trouble.What happens with the following code is that it prints to the
screen but the if condition on line 22 never gets executed.

http://pastie.org/549975

Any suggestions are appreciated.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/5f8757ba/attachment.html>

From contact at xavierho.com  Fri Jul 17 18:07:13 2009
From: contact at xavierho.com (Xavier Ho)
Date: Sat, 18 Jul 2009 06:07:13 +0800
Subject: Try... except....Try again?
In-Reply-To: <h3qs5u$1cr$1@ger.gmane.org>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
	<h3qs5u$1cr$1@ger.gmane.org>
Message-ID: <2d56febf0907171507y75f6436ete75cb3f748ee838d@mail.gmail.com>

On Sat, Jul 18, 2009 at 5:58 AM, Lie Ryan <lie.1296 at gmail.com> wrote:

>
>
> If you're looking for speed, you should be aware that a failed
> try-clause is quite expensive in python and often (as in this case)
> codes using exception can be less readable than the one without since a
> program's flow in the case of exception is not linear (the non-linear
> execution is useful for quickly breaking out from nests of clauses, but
> not necessary in this case).


Was not aware that myself. Noted.


> Semantically, it is also wrong. Not finding the n'th prime in the cache
> is not really an exceptional case.
>
> If you insists on using a try-except clause, use it this way:
>
> Well, I don't have to use try-except. I think I got another idea though. I
could use an internal counter to keep track of how many prime numbers have
generated, and if not enough, generate more.

Thanks.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/9125440d/attachment.html>

From mabdelkader at gmail.com  Fri Jul 17 18:33:55 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Fri, 17 Jul 2009 18:33:55 -0400
Subject: creating my own logwatch in python
In-Reply-To: <e8075cdd0907171458g162db8aai9dc5ef6ba49ec886@mail.gmail.com>
References: <e8075cdd0907171458g162db8aai9dc5ef6ba49ec886@mail.gmail.com>
Message-ID: <148918f0907171533y4044b171h54e91c142a21b6cf@mail.gmail.com>

A few code critiques:
 -  Your code is not very help friendly because it can not be run, so I have
to deadlist debug it.
 -  There are various syntax errors in the code:
    - for example: file is not defined when you invoke tail(file)
 -  You are overshadowing a built-in type 'file' by that name, which is
confusing. PEP 8 states that if you want to use a keyword, the practice is
to put an underscore after it. So, it should become file_
 -  Getopt is very old and should not be used. You should use the better,
readable, optparse
 -  That while loop will consume 99% CPU because of the infinite loop
 -  line = file.readline() is guaranteed to return a newline OR an empty
string ONLY when an EOF is encountered since you're not specifying the
optional maximum read byte size. This means that all your characters are
strings. So, why do you explicitly convert each character to a string and
separate each character by a space? (line 18)
 - Line 19 will always return 0 because of line 18
 - Line 19->22 are completely redundant, since readline is guaranteed to
give you ONE line. You should just do if "uccess" in logString: ...

Hope this helps,
mahmoud mack abdelkader
http://blog.mahmoudimus.com/



On Fri, Jul 17, 2009 at 5:58 PM, LoD MoD <lodmod.dod at gmail.com> wrote:

> I am trying to fabricate a logwatch-type script in Python and I'm having
> some trouble.What happens with the following code is that it prints to the
> screen but the if condition on line 22 never gets executed.
>
> http://pastie.org/549975
>
> Any suggestions are appreciated.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/084f8280/attachment.html>

From zaki.rahaman at gmail.com  Fri Jul 17 18:39:33 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 15:39:33 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
	<mailman.3319.1247866273.8015.python-list@python.org>
Message-ID: <1e8faacc-f4bc-420a-8028-88e405abb81f@d4g2000yqa.googlegroups.com>

On Jul 17, 5:31?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Zaki wrote:
> > On Jul 17, 2:49 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> >> Zaki wrote:
> >>> Hey all,
> >>> I'm really new to Python and this may seem like a really dumb
> >>> question, but basically, I wrote a script to do the following, however
> >>> the processing time/memory usage is not what I'd like it to be. Any
> >>> suggestions?
> >>> Outline:
> >>> 1. Read tab delim files from a directory, files are of 3 types:
> >>> install, update, and q. All 3 types contain ID values that are the
> >>> only part of interest.
> >>> 2. Using set() and set.add(), generate a list of unique IDs from
> >>> install and update files.
> >>> 3. Using the set created in (2), check the q files to see if there are
> >>> matches for IDs. Keep all matches, and add any non matches (which only
> >>> occur once in the q file) to a queue of lines to be removed from teh q
> >>> files.
> >>> 4. Remove the lines in the q for each file. (I haven't quite written
> >>> the code for this, but I was going to implement this using csv.writer
> >>> and rewriting all the lines in the file except for the ones in the
> >>> removal queue).
> >>> Now, I've tried running this and it takes much longer than I'd like. I
> >>> was wondering if there might be a better way to do things (I thought
> >>> generator expressions might be a good way to attack this problem, as
> >>> you could generate the set, and then check to see if there's a match,
> >>> and write each line that way).
> >> Why are you checking and removing lines in 2 steps? Why not copy the
> >> matching lines to a new q file and then replace the old file with the
> >> new one (or, maybe, delete the new q file if no lines were removed)?
>
> > That's what I've done now.
>
> > Here is the final code that I have running. It's very much 'hack' type
> > code and not at all efficient or optimized and any help in optimizing
> > it would be greatly appreciated.
>
> > import csv
> > import sys
> > import os
> > import time
>
> > begin = time.time()
>
> > #Check minutes elapsed
> > def timeElapsed():
> > ? ? current = time.time()
> > ? ? elapsed = current-begin
> > ? ? return round(elapsed/60)
>
> > #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> > inputdir = sys.argv[1]
> > outputdir = sys.argv[2]
>
> > logfilenames = os.listdir(inputdir)
>
> > IDs = set() #IDs from update and install logs
> > foundOnceInQuery = set()
> > #foundTwiceInQuery = set()
> > #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> > Queue of IDs to remove from query logs (IDs found only once in query
> > logs)
>
> > #Generate Filename Queues For Install/Update Logs, Query Logs
> > iNuQ = []
> > queryQ = []
>
> > for filename in logfilenames:
> > ? ? if filename.startswith("par1.install") or filename.startswith
> > ("par1.update"):
>
> ? ? ? if filename.startswith(("par1.install", "par1.update")):
>
> > ? ? ? ? iNuQ.append(filename)
> > ? ? elif filename.startswith("par1.query"):
> > ? ? ? ? queryQ.append(filename)
>
> > totalfiles = len(iNuQ) + len(queryQ)
> > print "Total # of Files to be Processed:" , totalfiles
> > print "Install/Update Logs to be processed:" , len(iNuQ)
> > print "Query logs to be processed:" , len(queryQ)
>
> > #Process install/update queue to generate list of valid IDs
> > currentfile = 1
> > for file in iNuQ:
>
> ?> ? ? print "Processing", currentfile, "install/update log out of", len
> ?> (iNuQ)
> ?> ? ? print timeElapsed()
> ?> ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> ?> ? ? for row in reader:
> ?> ? ? ? ? IDs.add(row[2])
> ?> ? ? currentfile+=1
>
> Best not to call it 'file'; that's a built-in name.
>
> Also you could use 'enumerate', and joining filepaths is safer with
> os.path.join().
>
> for currentfile, filename in enumerate(iNuQ, start=1):
> ? ? ?print "Processing", currentfile, "install/update log out of", len(iNuQ)
> ? ? ?print timeElapsed()
> ? ? ?current_path = os.path.join(inputdir, filename)
> ? ? ?reader = csv.reader(open(current_path), delimiter = '\t')
> ? ? ?for row in reader:
> ? ? ? ? ?IDs.add(row[2])
>
>
>
> > print "Finished processing install/update logs"
> > print "Unique IDs found:" , len(IDs)
> > print "Total Time Elapsed:", timeElapsed()
>
> > currentfile = 1
> > for file in queryQ:
>
> Similar remarks to above ...
>
> > ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> > ? ? print timeElapsed()
> > ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> > ? ? outputfile = csv.writer(open(outputdir+file), 'w')
>
> ... and also here.
>
> > ? ? for row in reader:
> > ? ? ? ? if row[2] in IDs:
> > ? ? ? ? ? ? ouputfile.writerow(row)
>
> Should be 'outputfile'.
>
> > ? ? ? ? else:
> > ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
>
> You're removing the ID here ...
>
> > ? ? ? ? ? ? ? ? outputfile.writerow(row)
> > ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> > ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> > ? ? ? ? ? ? else:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
>
> ... and adding it again here!
>
> > ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> > ? ? currentfile+=1
>
> For safety you should close the files after use.
>
> > print "Finished processing query logs and writing new files"
> > print "# of Query log entries removed:" , len(foundOnceInQuery)
> > print "Total Time Elapsed:", timeElapsed()
>
> Apart from that, it looks OK.
>
> How big are the q files? If they're not too big and most of the time
> you're not removing rows, you could put the output rows into a list and
> then create the output file only if rows have been removed, otherwise
> just copy the input file, which might be faster.

MRAB, could you please repost what I sent to you here as I meant to
post it in the main discussion.


From joncle at googlemail.com  Fri Jul 17 18:40:27 2009
From: joncle at googlemail.com (Jon Clements)
Date: Fri, 17 Jul 2009 15:40:27 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
Message-ID: <51ce01d3-4620-4e5f-b5b5-bd0e9fd6fd2c@w41g2000yqb.googlegroups.com>

On 17 July, 21:08, Zaki <zaki.raha... at gmail.com> wrote:
> On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
>
>
> > Zaki wrote:
> > > Hey all,
>
> > > I'm really new to Python and this may seem like a really dumb
> > > question, but basically, I wrote a script to do the following, however
> > > the processing time/memory usage is not what I'd like it to be. Any
> > > suggestions?
>
> > > Outline:
> > > 1. Read tab delim files from a directory, files are of 3 types:
> > > install, update, and q. All 3 types contain ID values that are the
> > > only part of interest.
> > > 2. Using set() and set.add(), generate a list of unique IDs from
> > > install and update files.
> > > 3. Using the set created in (2), check the q files to see if there are
> > > matches for IDs. Keep all matches, and add any non matches (which only
> > > occur once in the q file) to a queue of lines to be removed from teh q
> > > files.
> > > 4. Remove the lines in the q for each file. (I haven't quite written
> > > the code for this, but I was going to implement this using csv.writer
> > > and rewriting all the lines in the file except for the ones in the
> > > removal queue).
>
> > > Now, I've tried running this and it takes much longer than I'd like. I
> > > was wondering if there might be a better way to do things (I thought
> > > generator expressions might be a good way to attack this problem, as
> > > you could generate the set, and then check to see if there's a match,
> > > and write each line that way).
>
> > Why are you checking and removing lines in 2 steps? Why not copy the
> > matching lines to a new q file and then replace the old file with the
> > new one (or, maybe, delete the new q file if no lines were removed)?
>
> That's what I've done now.
>
> Here is the final code that I have running. It's very much 'hack' type
> code and not at all efficient or optimized and any help in optimizing
> it would be greatly appreciated.
>
> import csv
> import sys
> import os
> import time
>
> begin = time.time()
>
> #Check minutes elapsed
> def timeElapsed():
> ? ? current = time.time()
> ? ? elapsed = current-begin
> ? ? return round(elapsed/60)
>
> #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> inputdir = sys.argv[1]
> outputdir = sys.argv[2]
>
> logfilenames = os.listdir(inputdir)
>
> IDs = set() #IDs from update and install logs
> foundOnceInQuery = set()
> #foundTwiceInQuery = set()
> #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> Queue of IDs to remove from query logs (IDs found only once in query
> logs)
>
> #Generate Filename Queues For Install/Update Logs, Query Logs
> iNuQ = []
> queryQ = []
>
> for filename in logfilenames:
> ? ? if filename.startswith("par1.install") or filename.startswith
> ("par1.update"):
> ? ? ? ? iNuQ.append(filename)
> ? ? elif filename.startswith("par1.query"):
> ? ? ? ? queryQ.append(filename)
>
> totalfiles = len(iNuQ) + len(queryQ)
> print "Total # of Files to be Processed:" , totalfiles
> print "Install/Update Logs to be processed:" , len(iNuQ)
> print "Query logs to be processed:" , len(queryQ)
>
> #Process install/update queue to generate list of valid IDs
> currentfile = 1
> for file in iNuQ:
> ? ? print "Processing", currentfile, "install/update log out of", len
> (iNuQ)
> ? ? print timeElapsed()
> ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> ? ? for row in reader:
> ? ? ? ? IDs.add(row[2])
> ? ? currentfile+=1
>
> print "Finished processing install/update logs"
> print "Unique IDs found:" , len(IDs)
> print "Total Time Elapsed:", timeElapsed()
>
> currentfile = 1
> for file in queryQ:
> ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> ? ? print timeElapsed()
> ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> ? ? outputfile = csv.writer(open(outputdir+file), 'w')
> ? ? for row in reader:
> ? ? ? ? if row[2] in IDs:
> ? ? ? ? ? ? ouputfile.writerow(row)
> ? ? ? ? else:
> ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
> ? ? ? ? ? ? ? ? outputfile.writerow(row)
> ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> ? ? ? ? ? ? else:
> ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
> ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> ? ? currentfile+=1
>
> print "Finished processing query logs and writing new files"
> print "# of Query log entries removed:" , len(foundOnceInQuery)
> print "Total Time Elapsed:", timeElapsed()

Just a couple of ideas:

1) load the data into a sqlite3 database and use an SQL query to
extract your results (has the potential of doing what you want without
you coding it, plus if your requirements change, maybe somewhat more
flexible)

2) Pre-sort your input files via ID, then match-merge (may add some
time/space required to sort, but then the merge should be fairly
quick, plus you'll have access to the entire row in the process, not
just the ID)

Jon.


From zaki.rahaman at gmail.com  Fri Jul 17 18:57:48 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 15:57:48 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
	<51ce01d3-4620-4e5f-b5b5-bd0e9fd6fd2c@w41g2000yqb.googlegroups.com>
Message-ID: <8298385a-6f4b-44a5-b171-4871833f8dd2@c36g2000yqn.googlegroups.com>

On Jul 17, 6:40?pm, Jon Clements <jon... at googlemail.com> wrote:
> On 17 July, 21:08, Zaki <zaki.raha... at gmail.com> wrote:
>
>
>
> > On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > Zaki wrote:
> > > > Hey all,
>
> > > > I'm really new to Python and this may seem like a really dumb
> > > > question, but basically, I wrote a script to do the following, however
> > > > the processing time/memory usage is not what I'd like it to be. Any
> > > > suggestions?
>
> > > > Outline:
> > > > 1. Read tab delim files from a directory, files are of 3 types:
> > > > install, update, and q. All 3 types contain ID values that are the
> > > > only part of interest.
> > > > 2. Using set() and set.add(), generate a list of unique IDs from
> > > > install and update files.
> > > > 3. Using the set created in (2), check the q files to see if there are
> > > > matches for IDs. Keep all matches, and add any non matches (which only
> > > > occur once in the q file) to a queue of lines to be removed from teh q
> > > > files.
> > > > 4. Remove the lines in the q for each file. (I haven't quite written
> > > > the code for this, but I was going to implement this using csv.writer
> > > > and rewriting all the lines in the file except for the ones in the
> > > > removal queue).
>
> > > > Now, I've tried running this and it takes much longer than I'd like. I
> > > > was wondering if there might be a better way to do things (I thought
> > > > generator expressions might be a good way to attack this problem, as
> > > > you could generate the set, and then check to see if there's a match,
> > > > and write each line that way).
>
> > > Why are you checking and removing lines in 2 steps? Why not copy the
> > > matching lines to a new q file and then replace the old file with the
> > > new one (or, maybe, delete the new q file if no lines were removed)?
>
> > That's what I've done now.
>
> > Here is the final code that I have running. It's very much 'hack' type
> > code and not at all efficient or optimized and any help in optimizing
> > it would be greatly appreciated.
>
> > import csv
> > import sys
> > import os
> > import time
>
> > begin = time.time()
>
> > #Check minutes elapsed
> > def timeElapsed():
> > ? ? current = time.time()
> > ? ? elapsed = current-begin
> > ? ? return round(elapsed/60)
>
> > #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> > inputdir = sys.argv[1]
> > outputdir = sys.argv[2]
>
> > logfilenames = os.listdir(inputdir)
>
> > IDs = set() #IDs from update and install logs
> > foundOnceInQuery = set()
> > #foundTwiceInQuery = set()
> > #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> > Queue of IDs to remove from query logs (IDs found only once in query
> > logs)
>
> > #Generate Filename Queues For Install/Update Logs, Query Logs
> > iNuQ = []
> > queryQ = []
>
> > for filename in logfilenames:
> > ? ? if filename.startswith("par1.install") or filename.startswith
> > ("par1.update"):
> > ? ? ? ? iNuQ.append(filename)
> > ? ? elif filename.startswith("par1.query"):
> > ? ? ? ? queryQ.append(filename)
>
> > totalfiles = len(iNuQ) + len(queryQ)
> > print "Total # of Files to be Processed:" , totalfiles
> > print "Install/Update Logs to be processed:" , len(iNuQ)
> > print "Query logs to be processed:" , len(queryQ)
>
> > #Process install/update queue to generate list of valid IDs
> > currentfile = 1
> > for file in iNuQ:
> > ? ? print "Processing", currentfile, "install/update log out of", len
> > (iNuQ)
> > ? ? print timeElapsed()
> > ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> > ? ? for row in reader:
> > ? ? ? ? IDs.add(row[2])
> > ? ? currentfile+=1
>
> > print "Finished processing install/update logs"
> > print "Unique IDs found:" , len(IDs)
> > print "Total Time Elapsed:", timeElapsed()
>
> > currentfile = 1
> > for file in queryQ:
> > ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> > ? ? print timeElapsed()
> > ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> > ? ? outputfile = csv.writer(open(outputdir+file), 'w')
> > ? ? for row in reader:
> > ? ? ? ? if row[2] in IDs:
> > ? ? ? ? ? ? ouputfile.writerow(row)
> > ? ? ? ? else:
> > ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
> > ? ? ? ? ? ? ? ? outputfile.writerow(row)
> > ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> > ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> > ? ? ? ? ? ? else:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
> > ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> > ? ? currentfile+=1
>
> > print "Finished processing query logs and writing new files"
> > print "# of Query log entries removed:" , len(foundOnceInQuery)
> > print "Total Time Elapsed:", timeElapsed()
>
> Just a couple of ideas:
>
> 1) load the data into a sqlite3 database and use an SQL query to
> extract your results (has the potential of doing what you want without
> you coding it, plus if your requirements change, maybe somewhat more
> flexible)
>
> 2) Pre-sort your input files via ID, then match-merge (may add some
> time/space required to sort, but then the merge should be fairly
> quick, plus you'll have access to the entire row in the process, not
> just the ID)
>
> Jon.

Thanks Jon for the ideas, and yeah I might look into the SQLite
solution especially since I might need to do other sub selections. I
was also considering constructing a set for both install/update logs
and then another set for query logs and then do an intersection/other
set manipulations.

What I was really interested in was seeing if I could use generators
to try and accomplish what I'm doing especially since I'm uisng a lot
of for loops with conditionals and at this point it wouldn't matter if
the data is consumed in the intermediate steps before producing
output. Any help with getting this code in generator form would be
greatly appreciated.


From db3l.net at gmail.com  Fri Jul 17 19:09:35 2009
From: db3l.net at gmail.com (David Bolen)
Date: Fri, 17 Jul 2009 19:09:35 -0400
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
	<mailman.3219.1247753940.8015.python-list@python.org>
	<pan.2009.07.16.20.15.13.719000@nowhere.com>
Message-ID: <m2skgudhzk.fsf@valheru.db3l.homeip.net>

Nobody <nobody at nowhere.com> writes:

> On Thu, 16 Jul 2009 09:18:47 -0500, Tim Chase wrote:
>
>> Yes, the dictatorial "a tab always equals 8 spaces"
>
> Saying "always" is incorrect; it is more accurate to say that tab stops
> are every 8 columns unless proven otherwise, with the burden of proof
> falling on whoever wants to use something different.

I suspect Tim was referring to the Python tokenizer.  Internally,
barring the existence of one of a few Emacs/vi tab setting commands in
the file, Python always assigns the logical indentation level for a
tab to align with the next multiple-of-8 column.  This is unrelated to
how someone might choose to display such a file.

So mixing tabs and spaces and using a visual display setting of
something other than 8 for the tab size (other than one consistent
with an instruction embedded in the file) can yield a discrepancy
between what is shown on the screen and how the same code is perceived
by the Python compiler.  This in turn may cause errors or code to
execute at different indent levels than expected.  Thus, in general,
such a mixture is a bad idea, and as per this thread, no longer
permitted in a single block in Python 3.x.

-- David


From dresdek at gmail.com  Fri Jul 17 19:13:16 2009
From: dresdek at gmail.com (Matt)
Date: Fri, 17 Jul 2009 16:13:16 -0700 (PDT)
Subject: Unable to get Tkinter menubar to appear under OS X
References: <3737fd18-4973-4cc3-914d-fbdefdbbb8a7@t10g2000vbg.googlegroups.com>
	<6a9b0831-ce2e-417b-ab4b-419629d0a25d@u16g2000pru.googlegroups.com>
Message-ID: <a0280a4c-fa6c-46fd-91d0-c382e54b52e3@d4g2000prc.googlegroups.com>

same problem on OS 10.4, menu doesn't show up on either from tkinter
or wxpython, continuing search..


From ben+python at benfinney.id.au  Fri Jul 17 19:25:47 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 18 Jul 2009 09:25:47 +1000
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
Message-ID: <87ws66evt0.fsf@benfinney.id.au>

Phil <phily05 at gmail.com> writes:

> I was thinking that I could just, for example, 'from datetime import
> datetime' in __init__.py and have the ability to use 'datetime'
> anywhere in any of the modules in 'package'.

That would break one of the very nice features of Python's namespace
system: that, because nothing[0] comes into a module without an explicit
?import foo?, you can always trace where ?foo? came from in the source
code.

> This didn't work for me. Did I just do something wrong? Is what I am
> trying to do possible?

If it were possible, we'd have the nightmare of not knowing where the
names in a module were coming from, without having to search all over
the package just to find where these implicit imports were taking place.
No, thanks; I'm glad it's not possible.

> Thanks in advance.

[0] Two exceptions: There are a certain number of built-in names,
    strictly limited and well documented in the standard Python
    documentation. There are also those who use a namespace-clobbering
    ?from foo import *?, to which the solution is a clue-bat applied to
    the back of the skull.

-- 
 \        ?Pinky, are you pondering what I'm pondering?? ?Wuh, I think |
  `\      so, Brain, but how will we get three pink flamingos into one |
_o__)                     pair of Capri pants?? ?_Pinky and The Brain_ |
Ben Finney


From joncle at googlemail.com  Fri Jul 17 19:31:43 2009
From: joncle at googlemail.com (Jon Clements)
Date: Fri, 17 Jul 2009 16:31:43 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
	<51ce01d3-4620-4e5f-b5b5-bd0e9fd6fd2c@w41g2000yqb.googlegroups.com> 
	<8298385a-6f4b-44a5-b171-4871833f8dd2@c36g2000yqn.googlegroups.com>
Message-ID: <3ba0cc18-2cd0-416c-ad69-c7be138607e0@k1g2000yqf.googlegroups.com>

On 17 July, 23:57, Zaki <zaki.raha... at gmail.com> wrote:
> On Jul 17, 6:40?pm, Jon Clements <jon... at googlemail.com> wrote:
>
>
>
> > On 17 July, 21:08, Zaki <zaki.raha... at gmail.com> wrote:
>
> > > On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > > Zaki wrote:
> > > > > Hey all,
>
> > > > > I'm really new to Python and this may seem like a really dumb
> > > > > question, but basically, I wrote a script to do the following, however
> > > > > the processing time/memory usage is not what I'd like it to be. Any
> > > > > suggestions?
>
> > > > > Outline:
> > > > > 1. Read tab delim files from a directory, files are of 3 types:
> > > > > install, update, and q. All 3 types contain ID values that are the
> > > > > only part of interest.
> > > > > 2. Using set() and set.add(), generate a list of unique IDs from
> > > > > install and update files.
> > > > > 3. Using the set created in (2), check the q files to see if there are
> > > > > matches for IDs. Keep all matches, and add any non matches (which only
> > > > > occur once in the q file) to a queue of lines to be removed from teh q
> > > > > files.
> > > > > 4. Remove the lines in the q for each file. (I haven't quite written
> > > > > the code for this, but I was going to implement this using csv.writer
> > > > > and rewriting all the lines in the file except for the ones in the
> > > > > removal queue).
>
> > > > > Now, I've tried running this and it takes much longer than I'd like. I
> > > > > was wondering if there might be a better way to do things (I thought
> > > > > generator expressions might be a good way to attack this problem, as
> > > > > you could generate the set, and then check to see if there's a match,
> > > > > and write each line that way).
>
> > > > Why are you checking and removing lines in 2 steps? Why not copy the
> > > > matching lines to a new q file and then replace the old file with the
> > > > new one (or, maybe, delete the new q file if no lines were removed)?
>
> > > That's what I've done now.
>
> > > Here is the final code that I have running. It's very much 'hack' type
> > > code and not at all efficient or optimized and any help in optimizing
> > > it would be greatly appreciated.
>
> > > import csv
> > > import sys
> > > import os
> > > import time
>
> > > begin = time.time()
>
> > > #Check minutes elapsed
> > > def timeElapsed():
> > > ? ? current = time.time()
> > > ? ? elapsed = current-begin
> > > ? ? return round(elapsed/60)
>
> > > #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> > > inputdir = sys.argv[1]
> > > outputdir = sys.argv[2]
>
> > > logfilenames = os.listdir(inputdir)
>
> > > IDs = set() #IDs from update and install logs
> > > foundOnceInQuery = set()
> > > #foundTwiceInQuery = set()
> > > #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> > > Queue of IDs to remove from query logs (IDs found only once in query
> > > logs)
>
> > > #Generate Filename Queues For Install/Update Logs, Query Logs
> > > iNuQ = []
> > > queryQ = []
>
> > > for filename in logfilenames:
> > > ? ? if filename.startswith("par1.install") or filename.startswith
> > > ("par1.update"):
> > > ? ? ? ? iNuQ.append(filename)
> > > ? ? elif filename.startswith("par1.query"):
> > > ? ? ? ? queryQ.append(filename)
>
> > > totalfiles = len(iNuQ) + len(queryQ)
> > > print "Total # of Files to be Processed:" , totalfiles
> > > print "Install/Update Logs to be processed:" , len(iNuQ)
> > > print "Query logs to be processed:" , len(queryQ)
>
> > > #Process install/update queue to generate list of valid IDs
> > > currentfile = 1
> > > for file in iNuQ:
> > > ? ? print "Processing", currentfile, "install/update log out of", len
> > > (iNuQ)
> > > ? ? print timeElapsed()
> > > ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> > > ? ? for row in reader:
> > > ? ? ? ? IDs.add(row[2])
> > > ? ? currentfile+=1
>
> > > print "Finished processing install/update logs"
> > > print "Unique IDs found:" , len(IDs)
> > > print "Total Time Elapsed:", timeElapsed()
>
> > > currentfile = 1
> > > for file in queryQ:
> > > ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> > > ? ? print timeElapsed()
> > > ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> > > ? ? outputfile = csv.writer(open(outputdir+file), 'w')
> > > ? ? for row in reader:
> > > ? ? ? ? if row[2] in IDs:
> > > ? ? ? ? ? ? ouputfile.writerow(row)
> > > ? ? ? ? else:
> > > ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> > > ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
> > > ? ? ? ? ? ? ? ? outputfile.writerow(row)
> > > ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> > > ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> > > ? ? ? ? ? ? else:
> > > ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
> > > ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> > > ? ? currentfile+=1
>
> > > print "Finished processing query logs and writing new files"
> > > print "# of Query log entries removed:" , len(foundOnceInQuery)
> > > print "Total Time Elapsed:", timeElapsed()
>
> > Just a couple of ideas:
>
> > 1) load the data into a sqlite3 database and use an SQL query to
> > extract your results (has the potential of doing what you want without
> > you coding it, plus if your requirements change, maybe somewhat more
> > flexible)
>
> > 2) Pre-sort your input files via ID, then match-merge (may add some
> > time/space required to sort, but then the merge should be fairly
> > quick, plus you'll have access to the entire row in the process, not
> > just the ID)
>
> > Jon.
>
> Thanks Jon for the ideas, and yeah I might look into the SQLite
> solution especially since I might need to do other sub selections. I
> was also considering constructing a set for both install/update logs
> and then another set for query logs and then do an intersection/other
> set manipulations.
>
> What I was really interested in was seeing if I could use generators
> to try and accomplish what I'm doing especially since I'm uisng a lot
> of for loops with conditionals and at this point it wouldn't matter if
> the data is consumed in the intermediate steps before producing
> output. Any help with getting this code in generator form would be
> greatly appreciated.

Well effectively, you are using generators.

A very small optimisation might be to load the smallest set of data
first (if you are already, I apologise!). Read the others and see if
it's a matching ID, where it is, remove it from the smallest set, and
those are the records to be added on the next parse.

Posting when tired, so hope that makes some sense!

Otherwise, I'd be tempted to pre-sort or use sqlite.


From zac256 at gmail.com  Fri Jul 17 20:31:44 2009
From: zac256 at gmail.com (Zac Burns)
Date: Fri, 17 Jul 2009 17:31:44 -0700
Subject: Self optimizing iterable
Message-ID: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>

Greetings,

I would like a set like object that when iterated maintains a count of
where iteration stopped and then re-orders itself based on that count
so that the iteration stopped on the most bubble to the top.

An example use case for this would be for something like a large table
of regular expressions that would be iterated over trying to match in
some string. If some regular expressions are more statistically more
successful then the iteration will generally be short.

Does anyone know of a pre-existing recipe for this or feel like taking
on the challenge?

Bonus points for:
   Best possible BigO notation on switching order and iteration
   Threadsafety
   Extend to also include a mapping version



--
Zachary Burns
(407)590-4814
Aim - Zac256FL
Production Engineer (Digital Overlord)
Zindagi Games


From http  Fri Jul 17 20:40:32 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 17:40:32 -0700
Subject: Self optimizing iterable
References: <mailman.3325.1247877108.8015.python-list@python.org>
Message-ID: <7xbpniombj.fsf@ruckus.brouhaha.com>

Zac Burns <zac256 at gmail.com> writes:
> An example use case for this would be for something like a large table
> of regular expressions that would be iterated over trying to match in
> some string. If some regular expressions are more statistically more
> successful then the iteration will generally be short.

Generally if you are matching against a bunch of regexps, they will
tend to match overlapping sets, so you want to control precisely what
order they are tested in.  Having stuff bubble around based on hit
counts doesn't sound good.


From zac256 at gmail.com  Fri Jul 17 20:43:21 2009
From: zac256 at gmail.com (Zac Burns)
Date: Fri, 17 Jul 2009 17:43:21 -0700
Subject: Retrieving a partial pickle
Message-ID: <333edbe80907171743n6e72f5b8p7c1c6ab668cff7df@mail.gmail.com>

I have a large pickle file, which happens to be a list with lots of
objects in it.

What sort of things can I do without unpickling the whole object?

I would particularly like to retrieve one of the elements in the list
without unpicking the whole object.

If the answer is not specific to lists that would be useful (works on
getting items in a dictionary, or doing introspection on the objects
or whatever)

--
Zachary Burns
(407)590-4814
Aim - Zac256FL
Production Engineer (Digital Overlord)
Zindagi Games


From python at mrabarnett.plus.com  Fri Jul 17 20:54:22 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 18 Jul 2009 01:54:22 +0100
Subject: Self optimizing iterable
In-Reply-To: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>
References: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>
Message-ID: <4A611D3E.90806@mrabarnett.plus.com>

Zac Burns wrote:
> Greetings,
> 
> I would like a set like object that when iterated maintains a count of
> where iteration stopped and then re-orders itself based on that count
> so that the iteration stopped on the most bubble to the top.
> 
> An example use case for this would be for something like a large table
> of regular expressions that would be iterated over trying to match in
> some string. If some regular expressions are more statistically more
> successful then the iteration will generally be short.
> 
> Does anyone know of a pre-existing recipe for this or feel like taking
> on the challenge?
> 
> Bonus points for:
>    Best possible BigO notation on switching order and iteration
>    Threadsafety
>    Extend to also include a mapping version
> 
That's not a set, but a Most Recently Used list.


From gagsl-py2 at yahoo.com.ar  Fri Jul 17 21:09:22 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 17 Jul 2009 22:09:22 -0300
Subject: Self optimizing iterable
References: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>
Message-ID: <op.uw8n5wfkx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 21:31:44 -0300, Zac Burns <zac256 at gmail.com> escribi?:

> I would like a set like object that when iterated maintains a count of
> where iteration stopped and then re-orders itself based on that count
> so that the iteration stopped on the most bubble to the top.
>
> An example use case for this would be for something like a large table
> of regular expressions that would be iterated over trying to match in
> some string. If some regular expressions are more statistically more
> successful then the iteration will generally be short.

If you require a certain order, it's not a set; better to use a list.
The code below extends the builtin list type to add a "promote" method;  
lst.promote(3) "bubbles" lst[3] up (exchanging lst[3] with lst[2]). It's  
thread safe, and O(1).

<code>
import threading

class XList(list):
   #
   @property
   def lock(self):
     lock = getattr(self, '_lock', None)
     if lock is None: lock = self._lock = threading.Lock()
     return lock
   #
   def promote(self, index):
     if index<0: index += len(self)
     if index>0:
       with self.lock:
         self[index], self[index-1] = self[index-1], self[index]
</code>

py> a = XList('python')
py> a
['p', 'y', 't', 'h', 'o', 'n']
py> a.promote(3)
py> a
['p', 'y', 'h', 't', 'o', 'n']
py> a.promote(2)
py> a
['p', 'h', 'y', 't', 'o', 'n']
py> a.promote(-1)
py> a
['p', 'h', 'y', 't', 'n', 'o']
py> a.promote(0)
py> a
['p', 'h', 'y', 't', 'n', 'o']

An example, looking for a matching regular expression:

for index,expr in enumerate(exprlist):
   m = expr.match(txt)
   if m:
      dosomethingwith(m)
      exprlist.promote(index)
      break

After many calls, the most frequently matched expressions appear towards  
the front of the list.

>    Extend to also include a mapping version

I'm unsure if this point is still applicable. I'm using a list here, not a  
set as in your original proposal.

-- 
Gabriel Genellina



From pfeldman at verizon.net  Fri Jul 17 21:09:37 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 17 Jul 2009 18:09:37 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5DE5E7.5070003@mrabarnett.plus.com>
References: <24485116.post@talk.nabble.com>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<4A5DE5E7.5070003@mrabarnett.plus.com>
Message-ID: <24543805.post@talk.nabble.com>


Suppose that 'xor' returns the value that is true when only one value is
true, and False otherwise.  This definition of xor doesn't have the standard
associative property, that is,

(a xor b) xor c

will not necessarily equal

a xor (b xor c)

To see that this is the case, let a= 1, b= 2, and c= 3.

(a xor b) xor c

yields 3, while

a xor (b xor c)

yields 1.  So, I'd prefer an xor operator that simply returns True or False.

Phillip


MRAB-2 wrote:
> 
> 
> <snip>
> 
> What values should 'xor' return? IMHO, if only one of the values is true
> then it should return that value, otherwise it should return False.
> 
>      1 xor 0 => 1
>      0 xor 2 => 2
>      1 xor 2 => False
>      0 xor 0 => False
> 
> This is because it's a Boolean operator, so it should fall back to
> Boolean values when necessary, like 'not':
> 
>      not 0 => True
>      not 1 => False
> 
> Also:
> 
>      x and y and z => (x and y) and z
>      x or y or z => (x or y) or z
> 
> therefore:
> 
>      x xor y xor z => (x xor y) xor z
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24543805.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From pfeldman at verizon.net  Fri Jul 17 21:12:31 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 17 Jul 2009 18:12:31 -0700 (PDT)
Subject: PDF version of Python Tutorial?
Message-ID: <24543817.post@talk.nabble.com>


Does anyone know if there is a PDF version of the Python Tutorial (URL=
http://www.python.org/doc/current/tutorial/)?
-- 
View this message in context: http://www.nabble.com/PDF-version-of-Python-Tutorial--tp24543817p24543817.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From pavlovevidence at gmail.com  Fri Jul 17 21:35:33 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 17 Jul 2009 18:35:33 -0700 (PDT)
Subject: Self optimizing iterable
References: <mailman.3325.1247877108.8015.python-list@python.org> 
	<7xbpniombj.fsf@ruckus.brouhaha.com>
Message-ID: <97c6fdf0-0364-4669-bdd5-35e8b567a38c@o36g2000vbl.googlegroups.com>

On Jul 17, 5:40?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Zac Burns <zac... at gmail.com> writes:
> > An example use case for this would be for something like a large table
> > of regular expressions that would be iterated over trying to match in
> > some string. If some regular expressions are more statistically more
> > successful then the iteration will generally be short.
>
> Generally if you are matching against a bunch of regexps, they will
> tend to match overlapping sets, so you want to control precisely what
> order they are tested in. ?Having stuff bubble around based on hit
> counts doesn't sound good.

As a corrollary, if you happen to be matching non-overlapping sets,
then it is a red flag that there could be some other (better) way to
dispatch than a linear regexp search.  For instance, if all your
regexps start with a different keyword, then you should dispatch on
that keyword using a dictionary.  A regexp can be used after
dispatching to extract parameters if necessary.

It's possible to have disjoint regexps without a simple dispatch
criterion, but I'd guess that's less common.


Carl Banks


From ronn.ross at gmail.com  Fri Jul 17 21:42:43 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Fri, 17 Jul 2009 21:42:43 -0400
Subject: Beginners question
Message-ID: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>

How do you define a global variable in a class. I tried this with do
success:
class ClassName:
    global_var = 1

    def some_methos():
        print global_var

This doesn't work. What am I doing wrong?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/0527713c/attachment.html>

From sjmachin at lexicon.net  Fri Jul 17 21:54:11 2009
From: sjmachin at lexicon.net (John Machin)
Date: Fri, 17 Jul 2009 18:54:11 -0700 (PDT)
Subject: Find first matching substring
References: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>
Message-ID: <470ebc06-3e84-41c8-bd8e-0a342bb4ea28@y10g2000prg.googlegroups.com>

On Jul 18, 2:11?am, Eloff <dan.el... at gmail.com> wrote:
> Almost every time I've had to do parsing of text over the last 5 years
> I've needed this function:
[snip]
> It finds the first matching substring in the target string, if there
> is more than one match, it returns the position of the match that
> occurs at the lowest index in the string.

Alternatives:
(1) re.search(r"sub0|sub1|...", ...)
(2) google "Aho Corasick Python" (one result should be a thread in
this newsgroup within the last week)


From gabrielmonnerat at gmail.com  Fri Jul 17 22:03:32 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Fri, 17 Jul 2009 23:03:32 -0300
Subject: Beginners question
In-Reply-To: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <4A612D74.80908@gmail.com>

Ronn Ross wrote:
> How do you define a global variable in a class. I tried this with do 
> success:
> class ClassName:
>     global_var = 1
>    
>     def some_methos():
>         print global_var
>
> This doesn't work. What am I doing wrong?
You need pass "self" to the function and "global_var" needs be called 
with self.

class ClassName:
    global_var = 1
   
    def some_methos(self):
        print self.global_var


Gabriel M. Monnerat


From marduk at letterboxes.org  Fri Jul 17 22:13:24 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Fri, 17 Jul 2009 22:13:24 -0400
Subject: Beginners question
In-Reply-To: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <1247883209.28511.8.camel@centar>

On Fri, 2009-07-17 at 21:42 -0400, Ronn Ross wrote:
> How do you define a global variable in a class.

I bit of a mix-up with words here.  A variable can be a class variable
or a global variable (wrt the module).. not both.

>  I tried this with do success:
> class ClassName:
>     global_var = 1
>     
>     def some_methos():
>         print global_var
> 
> This doesn't work. What am I doing wrong?

You could have posted the error message... Two things are wrong here.
The first, if some_methos() is a method of ClassName then it should have
at least one parameter, which is the instance of the class (i.e.
"self"), so

    def some_methos(self):

The second problem is that global_var is not local so you need to
specify the scope.  You can either use

    print ClassName.global_var

or

    print self.global_var

I'm not sure which one is better though I prefer the former because it
makes it clearer to the reader that it's a class variable and not an
instance variable.

HTH,
-a




From nohics at gmail.com  Fri Jul 17 22:40:32 2009
From: nohics at gmail.com (nohics nohics)
Date: Sat, 18 Jul 2009 03:40:32 +0100
Subject: Beginners question
In-Reply-To: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <e4de9e30907171940s28a161cct3bc362516a1a20a6@mail.gmail.com>

When defining your class methods, you *must* explicitly list self as the
first argument for each method, including __init__. When you call a method
of an ancestor class from within your class, you *must* include the
selfargument. But when you call your class method from outside, you do
not
specify anything for the self argument; you skip it entirely, and
Pythonautomatically adds the instance reference for you. I am aware
that this is
confusing at first; it's not really inconsistent, but it may appear
inconsistent because it relies on a distinction (between bound and unbound
methods) that you don't know about yet.

So, you have to do:

class ClassName:
    self.global_var = 1
    def some_methos(self):
        print self.global_var

2009/7/18 Ronn Ross <ronn.ross at gmail.com>

> How do you define a global variable in a class. I tried this with do
> success:
> class ClassName:
>     global_var = 1
>
>     def some_methos():
>         print global_var
>
> This doesn't work. What am I doing wrong?
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/472c1523/attachment.html>

From contact at xavierho.com  Fri Jul 17 22:48:28 2009
From: contact at xavierho.com (Xavier Ho)
Date: Sat, 18 Jul 2009 10:48:28 +0800
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907171947s6a4a010fp124146d54d560bf4@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
	<h3qs5u$1cr$1@ger.gmane.org>
	<2d56febf0907171507y75f6436ete75cb3f748ee838d@mail.gmail.com>
	<4A611D89.7040603@ieee.org>
	<2d56febf0907171947s6a4a010fp124146d54d560bf4@mail.gmail.com>
Message-ID: <2d56febf0907171948l35e73c14gf02bc3c6ef11d493@mail.gmail.com>

Darn it.

On Sat, Jul 18, 2009 at 8:55 AM, Dave Angel <davea at ieee.org> wrote:

>
> You don't need a counter.  len() will tell you the size of the list of
> primes.


Does len() go through and count by itself, or does it actually keep track of
the size and just return the memory? I always thought it would go through
and count, which may take some time. I could be wrong.

>
> And, just in case you're still interested, that
>     for i in range()
>
> earlier in the thread has the overhead of building a (possibly) large list
> of integers, just in case we might need to loop.


Right, so for i in xrange() would be a better choice?

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/64fe6804/attachment.html>

From gabrielmonnerat at gmail.com  Fri Jul 17 23:06:31 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Sat, 18 Jul 2009 00:06:31 -0300
Subject: Beginners question
In-Reply-To: <e4de9e30907171940s28a161cct3bc362516a1a20a6@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
	<e4de9e30907171940s28a161cct3bc362516a1a20a6@mail.gmail.com>
Message-ID: <4A613C37.8090808@gmail.com>

nohics nohics wrote:
> When defining your class methods, you /must/ explicitly list self as 
> the first argument for each method, including __init__. When you call 
> a method of an ancestor class from within your class, you /must/ 
> include the self argument. But when you call your class method from 
> outside, you do not specify anything for the self argument; you skip 
> it entirely, and Python automatically adds the instance reference for 
> you. I am aware that this is confusing at first; it's not really 
> inconsistent, but it may appear inconsistent because it relies on a 
> distinction (between bound and unbound methods) that you don't know 
> about yet.
>
> So, you have to do:
>
> class ClassName:
>     self.global_var = 1
self isn't exists in this context.

 >>> class ClassName:
...       self.global_var = 1
...       def some_methods(self):
...         print self.global_var
...
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in ClassName
NameError: name 'self' is not defined

If you want a variable of instance you can use __init__

 >>> class ClassName:
...       def __init__(self):
...           self.global_var = 1
...       def some_methods(self):
...           print self.global_var

Now "global_var" is created when ClassName is instantiated

 >>> ClassName.global_var
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: class ClassName has no attribute 'global_var'
 >>> c = ClassName()
 >>> c.global_var
1

>     def some_methos(self):
>         print self.global_var
>
> 2009/7/18 Ronn Ross <ronn.ross at gmail.com <mailto:ronn.ross at gmail.com>>
>
>     How do you define a global variable in a class. I tried this with
>     do success:
>     class ClassName:
>         global_var = 1
>        
>         def some_methos():
>             print global_var
>
>     This doesn't work. What am I doing wrong?
>
>     --
>     http://mail.python.org/mailman/listinfo/python-list
>
>



From drobinow at gmail.com  Fri Jul 17 23:09:44 2009
From: drobinow at gmail.com (David Robinow)
Date: Fri, 17 Jul 2009 23:09:44 -0400
Subject: PDF version of Python Tutorial?
In-Reply-To: <24543817.post@talk.nabble.com>
References: <24543817.post@talk.nabble.com>
Message-ID: <4eb0089f0907172009t1ba9331bx24042c497b1d2b96@mail.gmail.com>

On Fri, Jul 17, 2009 at 9:12 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Does anyone know if there is a PDF version of the Python Tutorial (URL=
> http://www.python.org/doc/current/tutorial/)?

http://docs.python.org/download.html


From gagsl-py2 at yahoo.com.ar  Fri Jul 17 23:34:35 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 18 Jul 2009 00:34:35 -0300
Subject: PDF version of Python Tutorial?
References: <24543817.post@talk.nabble.com>
Message-ID: <op.uw8s1szxx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 22:12:31 -0300, Dr. Phillip M. Feldman
<pfeldman at verizon.net> escribi?:

> Does anyone know if there is a PDF version of the Python Tutorial (URL=
> http://www.python.org/doc/current/tutorial/)?

  From that page, click on the top left corner to go up one level, and
you'll see a download link.
Or, starting on http://www.python.org/doc/ you can navigate to the desired
document.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 17 23:34:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 18 Jul 2009 00:34:39 -0300
Subject: Beginners question
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <op.uw8utxorx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 22:42:43 -0300, Ronn Ross <ronn.ross at gmail.com>
escribi?:

> How do you define a global variable in a class. I tried this with do
> success:
> class ClassName:
>     global_var = 1
>
>     def some_method(self):
>         print global_var
>
> This doesn't work. What am I doing wrong?

[some typos fixed]

In Python, a "variable" is just a name in a namespace that references
another object.
There are five possible namespaces here:

- The local namespace, that is, the namespace inside some_method. All
assigned-to names that appear inside the function (there is none in this
case) are in the local namespace. But you're not interested on these local
names, I presume, because you said "global"

- The global namespace: the namespace of the module containing the code
(NOT a "super-global" namespace shared by all modules). Names in this
namespace are "global" in the sense that all code in the same module can
reference them. But they're not restricted to any class, as you requested.
To use a global name in an expression, just write it. To assign a new
value to a global name, you must use the "global" statement if you're
inside a function (else, it's considered a local name, see above).

- The built-in namespace: like a super-global namespace, it is searched
last when looking for an unqualified name; by example, the "len" function.
For most purposes, you should consider the built-in namespace read-only.

- The instance namespace: each object has its own namespace; you access
its names using dotted attributes: obj.name -- or self.attribute when
inside a method. The instance namespace is not determined by the object
type or class; any object may contain any attribute name (in general).

- The class namespace: classes may contain attributes too (like any other
object, because classes are objects too). In your code above, you may use
ClassName.global_var to refer to such class attribute. To resolve a dotted
attribute name, Python searches the instance first -- and if no match is
found, then the class namespace is searched too: this way, class
attributes effectively are "default values" for instance attributes. Since
all existing instances of a certain class share the same class, this is
like a "shared attribute" between all instances (like "static members" in
other languages). Inside some_method above, you may use self.global_var or
ClassName.global_var -- but once you *assign* something to the instance
attribute (self.global_var = xxx), the class attribute is shadowed and you
may reference it using ClassName.global_var only.

-- 
Gabriel Genellina



From drobinow at gmail.com  Fri Jul 17 23:51:46 2009
From: drobinow at gmail.com (David Robinow)
Date: Fri, 17 Jul 2009 23:51:46 -0400
Subject: turtle dump
In-Reply-To: <h3qn5k$jot$1@ger.gmane.org>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com> <h3obqg$aru$1@ger.gmane.org>
	<mailman.3246.1247792169.8015.python-list@python.org>
	<h3p5mm$o6s$01$1@news.t-online.com> <h3qn5k$jot$1@ger.gmane.org>
Message-ID: <4eb0089f0907172051v1b206a47r4326e7447f3d0637@mail.gmail.com>

>> If you want to generate high-quality graphics easily you need different
>> primitives.
>>
>> http://cairographics.org
>>
>> has Python bindings, but I don't know if it's available on Windows.
>
> Effectively not, as far as I can tell. PyCairo appears to be *nix and
> require later binaries than those available from gtk site referenced from
> cairo site.

http://ftp.gnome.org/pub/GNOME/binaries/win32/pycairo/1.4/
 Works for me.


From gagsl-py2 at yahoo.com.ar  Sat Jul 18 00:13:18 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 18 Jul 2009 01:13:18 -0300
Subject: Retrieving a partial pickle
References: <333edbe80907171743n6e72f5b8p7c1c6ab668cff7df@mail.gmail.com>
Message-ID: <op.uw8woga0x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 21:43:21 -0300, Zac Burns <zac256 at gmail.com> escribi?:

> I have a large pickle file, which happens to be a list with lots of
> objects in it.
>
> What sort of things can I do without unpickling the whole object?
>
> I would particularly like to retrieve one of the elements in the list
> without unpicking the whole object.

I'm afraid you can't do that, in general. A pickle is actually *code* for  
a stack-based machine; you have to execute all the previous instructions  
to have a sane stack contents; it's not possible (at least, not easily)  
just to jump in the middle of the pickle and execute just a section.

> If the answer is not specific to lists that would be useful (works on
> getting items in a dictionary, or doing introspection on the objects
> or whatever)

The pickletools module might be a starting point:  
http://docs.python.org/library/pickletools.html -- Try the Python Cookbook  
too http://code.activestate.com/recipes/langs/python/

-- 
Gabriel Genellina



From http  Sat Jul 18 00:47:03 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 21:47:03 -0700
Subject: Einstein summation notation
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
	<mailman.3290.1247847474.8015.python-list@python.org>
Message-ID: <7xprbybnso.fsf@ruckus.brouhaha.com>

Ethan Furman <ethan at stoneleaf.us> writes:
> Or if any(p for p in [header, body, footer, whatever, ...])

No need for the genexp:

   if any([header, body, footer, whatever, ...])

But, you are using the built-in bool cast either way.


From http  Sat Jul 18 00:49:02 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 21:49:02 -0700
Subject: Retrieving a partial pickle
References: <mailman.3326.1247877803.8015.python-list@python.org>
Message-ID: <7xljmmbnpd.fsf@ruckus.brouhaha.com>

Zac Burns <zac256 at gmail.com> writes:
> I have a large pickle file, which happens to be a list with lots of
> objects in it.
> What sort of things can I do without unpickling the whole object?

If it's for some kind of data recovery of a busted file, you could
code some awful hack to pull stuff out of the middle of the pickle,
but that's not the idea.  You may want the shelve module.


From torriem at gmail.com  Sat Jul 18 00:49:52 2009
From: torriem at gmail.com (Michael Torrie)
Date: Fri, 17 Jul 2009 22:49:52 -0600
Subject: getopt code NameError exception on logTail.py
In-Reply-To: <e8075cdd0907171132m361906fbw97dd20a58c930743@mail.gmail.com>
References: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>	<4A60BE10.5050905@mrabarnett.plus.com>
	<e8075cdd0907171132m361906fbw97dd20a58c930743@mail.gmail.com>
Message-ID: <4A615470.9080503@gmail.com>

LoD MoD wrote:
> In this instance the trackback was somewhat unhelpful.There problem was
> here:
> 
>            file = open(filename, 'r')
> 
> should be
> 
>            file = open(a, 'r')
> 
> args should be passed within the getopt riff

Well given the code you posted, this little "problem" you mention has
nothing to do with the traceback.  The code (as you posted it) still
does not define "process" anywhere.  Seems helpful enough to me.  If
you're not importing it from somewhere, then saying "it's defined
elsewhere" is still an error!


From torriem at gmail.com  Sat Jul 18 00:55:26 2009
From: torriem at gmail.com (Michael Torrie)
Date: Fri, 17 Jul 2009 22:55:26 -0600
Subject: Question regarding style/design..
In-Reply-To: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
Message-ID: <4A6155BE.80500@gmail.com>

Wells Oliver wrote:
> Sometimes I see relatively small application, generally task scripts,
> written as essentially a list of statements. Other times, I see them neatly
> divided into functions and then the "if __name__ == '__main__':" convention.
> Is there a preference? Is there an... application scope such that the
> preference shifts from the former to the latter? I understand the use of the
> __name__ == 'main' convention for building unit tests, but I'm mixed on
> using it in scripts/small applications.
> Thanks for any thoughts!

I always use the name guard thing for the simple reason that it lets me
reuse code by importing it as a module into other things.  My programs
often serve double purposes.  One is to be a standalone utility.  The
other is to be able to be used as a library from other code.  So the
name guard is essential.  For code that is intended to be in modules,
the name guard thing is indispensable for running unit tests.

For very short, one-off things, I may leave it off.  In any case I much
prefer having a name guard, then running various functions than the Java
style of writing a stupid static class with a static main method.
Always seemed like a paradigm hack to me.


From electronixtar at gmail.com  Sat Jul 18 01:03:05 2009
From: electronixtar at gmail.com (est)
Date: Fri, 17 Jul 2009 22:03:05 -0700 (PDT)
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
Message-ID: <0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>

On Jul 17, 10:48?am, Christian Tismer <tis... at stackless.com> wrote:
> Announcing Psyco V2 source release
> ----------------------------------
>
> This is the long awaited announcement of Psyco V2.
>
> Psyco V2 is a continuation of the well-known psyco project,
> which was called finished and was dis-continued by its author
> Armin Rigo in 2005, in favor of the PyPy project.
>
> This is a new project, using Psyco's code base with permission
> of Armin. Questions and complaints should go to me
> (tis... at stackless.com) or the mailing list
> (psyco-de... at lists.sourceforge.net);
> Armin is explicitly not in charge of (t)his project any longer!
>
> As one of the founders and an active member of the PyPy
> project, I was very happy to be invited to work on Psyco
> V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
> approach "an extension module that just makes Python faster".
>
> Psyco is a just-in-time compiler that accelerates arbitrary
> Python code by specialization. We believe that Psyco's approach
> can be carried out much further than it was tried so far, when
> it's first version was abandoned.
>
> This first V2 release is source-only. There is no web-site, yet,
> and there are no binaries for download. These will be available
> in a few days onhttp://www.psyco.org.
>
> For the time being, please stick with subversion access,
> building the extension module from source code. The repository
> is here:
>
> ? ? ?http://codespeak.net/svn/psyco/v2/dist
>
> Check-out the repository, and run the setup.py script,
> given that you have access to a C compiler.
>
> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
> is well being considered.
>
> The current improvements are, shortly:
>
> ? ?- Support for Python 2.4, 2.5 and 2.6
> ? ?- a lot of new builtins
> ? ?- generators, fast and fully supported.
>
> More information is coming soon onhttp://www.psyco.org.
>
> This is the beginning of a series of new Psyco versions.
> Many more improvements are prepared and about to be published,
> soon, starting with the current version 2.0.0 .
>
> Stay tuned, this is just the beginning of psyco's re-birth!
>
> For questions about Psyco V2, please join the mailing list
>
> ? ? ?psyco-de... at lists.sourceforge.net
>
> or contact me on IRC:
>
> ? ? ?#psyco on irc.freenode.net .
>
> Psyco V2 is fundamentally supported by FATTOC, LLC.
> Seehttp://www.fattoc.com.
>
> Without their continuous support, this work would not have
> been possible at all. I wish to express my deepest thanks
> to FATTOC, for allowing me to continue on Psyco with all the
> energy that this ambitious project needs, and will need.
>
> Further special thanks are going to
> Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
> Raymond Hettinger, Fabrizio Milo, Michael Foord,
> Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
> for all the support and discussions.
>
> Looking forward to a great future of Psyco!
>
> July 17, 2009
> --
> Christian Tismer ? ? ? ? ? ? :^) ? <mailto:tis... at stackless.com>
> tismerysoft GmbH ? ? ? ? ? ? : ? ? Have a break! Take a ride on Python's
> Johannes-Niemeyer-Weg 9A ? ? : ? ?*Starship*http://starship.python.net/
> 14109 Berlin ? ? ? ? ? ? ? ? : ? ? PGP key ->http://wwwkeys.pgp.net/
> work +49 30 802 86 56 ?mobile +49 173 24 18 776 ?fax +49 30 80 90 57 05
> PGP 0x57F3BF04 ? ? ? 9064 F4E1 D754 C2FF 1619 ?305B C09C 5A3B 57F3 BF04
> ? ? ? ?whom do you want to sponsor today? ?http://www.stackless.com/

congrats!

btw is psyco.org owned?


From tjreedy at udel.edu  Sat Jul 18 01:44:58 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 18 Jul 2009 01:44:58 -0400
Subject: turtle dump
In-Reply-To: <4eb0089f0907172051v1b206a47r4326e7447f3d0637@mail.gmail.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>	<h3o6hr$mmh$02$1@news.t-online.com>
	<h3obqg$aru$1@ger.gmane.org>	<mailman.3246.1247792169.8015.python-list@python.org>	<h3p5mm$o6s$01$1@news.t-online.com>
	<h3qn5k$jot$1@ger.gmane.org>
	<4eb0089f0907172051v1b206a47r4326e7447f3d0637@mail.gmail.com>
Message-ID: <h3rngr$j5i$1@ger.gmane.org>

David Robinow wrote:
>>> If you want to generate high-quality graphics easily you need different
>>> primitives.
>>>
>>> http://cairographics.org
>>>
>>> has Python bindings, but I don't know if it's available on Windows.
>> Effectively not, as far as I can tell. PyCairo appears to be *nix and
>> require later binaries than those available from gtk site referenced from
>> cairo site.
> 
> http://ftp.gnome.org/pub/GNOME/binaries/win32/pycairo/1.4/
>  Works for me.

Thanks. I did not see that referenced from the cairo site. Now if only 
there were a 3.1 version....

tjr



From __peter__ at web.de  Sat Jul 18 02:42:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 08:42:15 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com>
	<mailman.3245.1247785636.8015.python-list@python.org>
	<364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>
	<mailman.3313.1247863203.8015.python-list@python.org>
Message-ID: <h3rqrp$536$01$1@news.t-online.com>

Terry Reedy wrote:

> alex23 wrote:
> 
>> The help in iPython says the same, but also mentions that it's a
>> dynamically generated function, so it may not be picking up the
>> docstring that way. turtle.ScrolledCanvas.postscript is similarly
>> terse, but you can find more info in turtle.Canvas.postscript:
>> 
>>   Print the contents of the canvas to a postscript
>>   file. Valid options: colormap, colormode, file, fontmap,
>>   height, pageanchor, pageheight, pagewidth, pagex, pagey,
>>   rotate, witdh, x, y.
> 
> How, exactly, did you get that list?
> 
> tjr

[Python 3.1]
>>> import tkinter
>>> print(tkinter.Canvas.postscript.__doc__)
Print the contents of the canvas to a postscript
        file. Valid options: colormap, colormode, file, fontmap,
        height, pageanchor, pageheight, pagewidth, pagex, pagey,
        rotate, witdh, x, y.

Peter



From tismer at stackless.com  Sat Jul 18 02:50:07 2009
From: tismer at stackless.com (Christian Tismer)
Date: Sat, 18 Jul 2009 08:50:07 +0200
Subject: ANN: psyco V2
In-Reply-To: <0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>
Message-ID: <5661F6B6-371B-46C3-BAE6-FFE280DC78A3@stackless.com>

It is just being transferred

Von meinem iTouch gesendet

On Jul 18, 2009, at 7:03, est <electronixtar at gmail.com> wrote:

> On Jul 17, 10:48 am, Christian Tismer <tis... at stackless.com> wrote:
>> Announcing Psyco V2 source release
>> ----------------------------------
>>
>> This is the long awaited announcement of Psyco V2.
>>
>> Psyco V2 is a continuation of the well-known psyco project,
>> which was called finished and was dis-continued by its author
>> Armin Rigo in 2005, in favor of the PyPy project.
>>
>> This is a new project, using Psyco's code base with permission
>> of Armin. Questions and complaints should go to me
>> (tis... at stackless.com) or the mailing list
>> (psyco-de... at lists.sourceforge.net);
>> Armin is explicitly not in charge of (t)his project any longer!
>>
>> As one of the founders and an active member of the PyPy
>> project, I was very happy to be invited to work on Psyco
>> V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
>> approach "an extension module that just makes Python faster".
>>
>> Psyco is a just-in-time compiler that accelerates arbitrary
>> Python code by specialization. We believe that Psyco's approach
>> can be carried out much further than it was tried so far, when
>> it's first version was abandoned.
>>
>> This first V2 release is source-only. There is no web-site, yet,
>> and there are no binaries for download. These will be available
>> in a few days onhttp://www.psyco.org.
>>
>> For the time being, please stick with subversion access,
>> building the extension module from source code. The repository
>> is here:
>>
>>      http://codespeak.net/svn/psyco/v2/dist
>>
>> Check-out the repository, and run the setup.py script,
>> given that you have access to a C compiler.
>>
>> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
>> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
>> is well being considered.
>>
>> The current improvements are, shortly:
>>
>>    - Support for Python 2.4, 2.5 and 2.6
>>    - a lot of new builtins
>>    - generators, fast and fully supported.
>>
>> More information is coming soon onhttp://www.psyco.org.
>>
>> This is the beginning of a series of new Psyco versions.
>> Many more improvements are prepared and about to be published,
>> soon, starting with the current version 2.0.0 .
>>
>> Stay tuned, this is just the beginning of psyco's re-birth!
>>
>> For questions about Psyco V2, please join the mailing list
>>
>>      psyco-de... at lists.sourceforge.net
>>
>> or contact me on IRC:
>>
>>      #psyco on irc.freenode.net .
>>
>> Psyco V2 is fundamentally supported by FATTOC, LLC.
>> Seehttp://www.fattoc.com.
>>
>> Without their continuous support, this work would not have
>> been possible at all. I wish to express my deepest thanks
>> to FATTOC, for allowing me to continue on Psyco with all the
>> energy that this ambitious project needs, and will need.
>>
>> Further special thanks are going to
>> Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
>> Raymond Hettinger, Fabrizio Milo, Michael Foord,
>> Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
>> for all the support and discussions.
>>
>> Looking forward to a great future of Psyco!
>>
>> July 17, 2009
>> --
>> Christian Tismer             :^)   <mailto:tis... at stackless.com>
>> tismerysoft GmbH             :     Have a break! Take a ride on  
>> Python's
>> Johannes-Niemeyer-Weg 9A     :    *Starship*http://starship.python.net/
>> 14109 Berlin                 :     PGP key ->http://wwwkeys.pgp.net/
>> work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
>> PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3  
>> BF04
>>        whom do you want to sponsor today?  http://www.stackless.com/
>
> congrats!
>
> btw is psyco.org owned?
> -- 
> http://mail.python.org/mailman/listinfo/python-list


From amrita at iisermohali.ac.in  Sat Jul 18 03:09:21 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 18 Jul 2009 12:39:21 +0530 (IST)
Subject: how two join and arrange two files together
Message-ID: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>


Hi,

I have two files having entries like:--
fileA
8  ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98	C = 179.39
15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C = 177.18
23 ALA H = 8.78	N = 120.16 CA = 55.84 HA = 4.14	C = 179.93
and
fileB
ChainA: ALA8	-67.217297	-37.131330
ChainA: ALA21	-69.822977	-48.871282
ChainA: ALA23	-59.148095	-46.540043
ChainA: ALA33	-65.459303	-43.269718

i want to join thses two files in such a way that the output file will
contain column of both the files and the enties of similar position of ALA
will be together.so the output file should look something like:----
fileC
8  ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98	C = 179.39 ChainA:
ALA8	-67.217297	-37.131330
15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C = 177.18
                                                           ChainA:
ALA21	-69.822977	-48.871282
23 ALA H = 8.78	N = 120.16 CA = 55.84 HA = 4.14	C = 179.93 ChainA:
ALA23	-59.148095	-46.540043
                                                           ChainA:
ALA33	-65.459303	-43.269718



Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From kalyanchakravarthy at hyit.com  Sat Jul 18 03:14:23 2009
From: kalyanchakravarthy at hyit.com (Kalyan Chakravarthy)
Date: Sat, 18 Jul 2009 12:44:23 +0530
Subject: Python import Error
Message-ID: <8ca278430907180014k460f3798mafef6fc59379677b@mail.gmail.com>

Hi All,
                   I am using* Python 2.6, MySQL 4.0* , I have successfully
Instaled MySQLdb (*MySQL-python-1.2.3c1.win32-py2.6*) in my system. I tested
through command prompt with "import MySQLdb ", its not shwing any errors
(means its instaled successfully), I set Eneceranment variable for Python

I  am running simple application with import "MySQLdb" to get the connection
to MySQL, But its throwing "No module named MySQLdb", Please any one tell me
what couled be the reasion

is there any version miss match with python and MySQL ?

Since last 3days I am strugling on this

-- 
Regards
Kalyan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/d1108ce1/attachment.html>

From clp2 at rebertia.com  Sat Jul 18 03:19:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 00:19:23 -0700
Subject: how two join and arrange two files together
In-Reply-To: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>

On Sat, Jul 18, 2009 at 12:09 AM, <amrita at iisermohali.ac.in> wrote:
>
> Hi,
>
> I have two files having entries like:--
> fileA
> 8 ?ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93
> and
> fileB
> ChainA: ALA8 ? ?-67.217297 ? ? ?-37.131330
> ChainA: ALA21 ? -69.822977 ? ? ?-48.871282
> ChainA: ALA23 ? -59.148095 ? ? ?-46.540043
> ChainA: ALA33 ? -65.459303 ? ? ?-43.269718
>
> i want to join thses two files in such a way that the output file will
> contain column of both the files and the enties of similar position of ALA
> will be together.so the output file should look something like:----
> fileC
> 8 ?ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39 ChainA:
> ALA8 ? ?-67.217297 ? ? ?-37.131330
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ChainA:
> ALA21 ? -69.822977 ? ? ?-48.871282
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93 ChainA:
> ALA23 ? -59.148095 ? ? ?-46.540043
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ChainA:
> ALA33 ? -65.459303 ? ? ?-43.269718

This mailinglist is not a collection of free code monkeys. Show us
you've at least /tried/ to write this yourself, and tell us where
you're running into problems or what error you're getting.

See also http://catb.org/esr/faqs/smart-questions.html

Additionally, you might consider asking on the Indian Python
mailinglist instead:
http://mail.python.org/mailman/listinfo/bangpypers

- Chris


From amrita at iisermohali.ac.in  Sat Jul 18 03:39:09 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 18 Jul 2009 13:09:09 +0530 (IST)
Subject: how two join and arrange two files together
In-Reply-To: <50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
Message-ID: <23421.210.212.36.65.1247902749.squirrel@www.iisermohali.ac.in>

I tried to join these two files together using command.......

from itertools import izip
from os.path import exists

def parafiles(*files):
    vec = (open(f) for f in files if exists(f))
    data = izip(*vec)
    [f.close() for f in vec]
    return data

for data in parafiles('/home/amrita/alachems/chem1.txt',
'/home/amrita/secstr/secstr.txt'):
    print ' '.join(d.strip() for d in data)

it just joined the column of two files.

> On Sat, Jul 18, 2009 at 12:09 AM, <amrita at iisermohali.ac.in> wrote:
>>
>> Hi,
>>
>> I have two files having entries like:--
>> fileA
>> 8 ??ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39
>> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
>> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93
>> and
>> fileB
>> ChainA: ALA8 ?? ??-67.217297 ?? ?? ??-37.131330
>> ChainA: ALA21 ?? -69.822977 ?? ?? ??-48.871282
>> ChainA: ALA23 ?? -59.148095 ?? ?? ??-46.540043
>> ChainA: ALA33 ?? -65.459303 ?? ?? ??-43.269718
>>
>> i want to join thses two files in such a way that the output file will
>> contain column of both the files and the enties of similar position of
>> ALA
>> will be together.so the output file should look something like:----
>> fileC
>> 8 ??ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39 ChainA:
>> ALA8 ?? ??-67.217297 ?? ?? ??-37.131330
>> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
>> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ??
>> ?? ?? ?? ?? ?? ChainA:
>> ALA21 ?? -69.822977 ?? ?? ??-48.871282
>> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93 ChainA:
>> ALA23 ?? -59.148095 ?? ?? ??-46.540043
>> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ??
>> ?? ?? ?? ?? ?? ChainA:
>> ALA33 ?? -65.459303 ?? ?? ??-43.269718
>
> This mailinglist is not a collection of free code monkeys. Show us
> you've at least /tried/ to write this yourself, and tell us where
> you're running into problems or what error you're getting.
>
> See also http://catb.org/esr/faqs/smart-questions.html
>
> Additionally, you might consider asking on the Indian Python
> mailinglist instead:
> http://mail.python.org/mailman/listinfo/bangpypers
>
> - Chris
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From __peter__ at web.de  Sat Jul 18 05:17:33 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 11:17:33 +0200
Subject: how two join and arrange two files together
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
Message-ID: <h3s3uu$8pk$00$1@news.t-online.com>

amrita at iisermohali.ac.in wrote:

> I tried to join these two files together using command.......
> 
> from itertools import izip
> from os.path import exists
> 
> def parafiles(*files):
>     vec = (open(f) for f in files if exists(f))
>     data = izip(*vec)
>     [f.close() for f in vec]
>     return data
> 
> for data in parafiles('/home/amrita/alachems/chem1.txt',
> '/home/amrita/secstr/secstr.txt'):
>     print ' '.join(d.strip() for d in data)

parafiles has a bug: vec is a generator and hence cannot be run twice. 
Therefore the odd [f.close()...] list comprehension (don't use a list comp 
if you don't care about the result!) has no effect. 

If you change vec into a list you will be hit by another problem -- the for 
loop trying to operate on closed files. While the correct approach probably 
involves a contextlib.contextmanager I recommend that you concentrate on 
your real problem and keep parafiles() simple:

def parafiles(*files):
    open_files = (open(f) for f in files if exits(f))
    return izip(*open_files)

> it just joined the column of two files.

Can you make an effort to express clearly what you want, preferrably with a 
simple and unambiguous example?

Please keep the line widths below the threshold of 78 characters to avoid 
messing it up on its way to the reader.

Peter



From amrita at iisermohali.ac.in  Sat Jul 18 05:29:28 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 18 Jul 2009 14:59:28 +0530 (IST)
Subject: how two join and arrange two files together
In-Reply-To: <h3s3uu$8pk$00$1@news.t-online.com>
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
	<h3s3uu$8pk$00$1@news.t-online.com>
Message-ID: <2569.210.212.36.65.1247909368.squirrel@www.iisermohali.ac.in>

I want to join column of two different data file but i want that the
entries will match (example i mentioned in my first mail, the position of
ALA eill match) if its not matching then it will get printed as such.

> amrita at iisermohali.ac.in wrote:
>
>> I tried to join these two files together using command.......
>>
>> from itertools import izip
>> from os.path import exists
>>
>> def parafiles(*files):
>>     vec = (open(f) for f in files if exists(f))
>>     data = izip(*vec)
>>     [f.close() for f in vec]
>>     return data
>>
>> for data in parafiles('/home/amrita/alachems/chem1.txt',
>> '/home/amrita/secstr/secstr.txt'):
>>     print ' '.join(d.strip() for d in data)
>
> parafiles has a bug: vec is a generator and hence cannot be run twice.
> Therefore the odd [f.close()...] list comprehension (don't use a list comp
> if you don't care about the result!) has no effect.
>
> If you change vec into a list you will be hit by another problem -- the
> for
> loop trying to operate on closed files. While the correct approach
> probably
> involves a contextlib.contextmanager I recommend that you concentrate on
> your real problem and keep parafiles() simple:
>
> def parafiles(*files):
>     open_files = (open(f) for f in files if exits(f))
>     return izip(*open_files)
>
>> it just joined the column of two files.
>
> Can you make an effort to express clearly what you want, preferrably with
> a
> simple and unambiguous example?
>
> Please keep the line widths below the threshold of 78 characters to avoid
> messing it up on its way to the reader.
>
> Peter
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From dickinsm at gmail.com  Sat Jul 18 05:50:06 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Sat, 18 Jul 2009 02:50:06 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org> 
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com> 
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org> 
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com> 
	<mailman.3216.1247751117.8015.python-list@python.org>
	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi> 
	<h3nk10$tvu$1@ger.gmane.org> <4A5F5759.4010600@sequans.com> 
	<1247774222.4a5f860ec3cfa@mail.uh.cu>
	<mailman.3268.1247828799.8015.python-list@python.org>
Message-ID: <9a623957-aece-413f-817a-88c76b9e25f4@y17g2000yqn.googlegroups.com>

On Jul 17, 12:06?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> I was saying that using boolean operators with object instead of boolean
> values is error prone,

I agree with this to some extent.  After all, Python conditional
expressions were eventually introduced in response to buggy uses of
the 'a and b or c' idiom.  See PEP 308, and:

http://mail.python.org/pipermail/python-dev/2005-September/056546.html

In my own code, I'm finding myself increasingly using conditional
expressions where I would once have used 'and' or 'or':

daysInAdvance = int(inputVar) if inputVar is not None else 0

--
Mark


From markbak at gmail.com  Sat Jul 18 06:21:57 2009
From: markbak at gmail.com (Mark Bakker)
Date: Sat, 18 Jul 2009 12:21:57 +0200
Subject: difference in printing to screen Mac / Windows
Message-ID: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com>

Hello list

I notice a difference between running the following script on my Mac and on
a PC:

from time import sleep
for i in range(10):
   print i,
   sleep(2)

On my PC this prints a number every 2 seconds. This is the behavior I want.

On my Mac Python waits 10*2 = 20 seconds, and then prints 0 1 2 3 4 5 6 7 8
9

Any thoughts on how I can make Python behave to get the Python behavior of
my PC on my Mac?

Thanks,

Mark
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/1cfdfa7f/attachment.html>

From __peter__ at web.de  Sat Jul 18 06:40:01 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 12:40:01 +0200
Subject: how two join and arrange two files together
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
	<h3s3uu$8pk$00$1@news.t-online.com>
	<mailman.3352.1247909380.8015.python-list@python.org>
Message-ID: <h3s8pj$j92$00$1@news.t-online.com>

amrita at iisermohali.ac.in wrote:

>> Can you make an effort to express clearly what you want, preferrably with
>> a simple and unambiguous example?

> I want to join column of two different data file but i want that the
> entries will match (example i mentioned in my first mail, the position of
> ALA eill match) if its not matching then it will get printed as such.

Just say "No" if you mean it.

My best guess:

from collections import defaultdict

def merge(sources):
    blanks = [blank for items, blank, keyfunc in sources]
    d = defaultdict(lambda: blanks[:])
    for index, (items, blank, keyfunc) in enumerate(sources):
        for item in items:
            d[keyfunc(item)][index] = item
    for key in sorted(d):
        yield d[key]

if __name__ == "__main__":
    from StringIO import StringIO
    a = StringIO("""\
a alpha
c beta
d gamma
""")

    b = StringIO("""\
a one
b two
d three
e four
""")

    c = StringIO("""\
a 111
b 222
f 333
""")

    def key(line):
        return line[:1]
    def source(stream, blank="", key=key):
        return (line.strip() for line in stream), blank, key
    for m in merge([source(x) for x in [a,b,c]]):
        print "|".join(c.ljust(10) for c in m)





From python.list at tim.thechases.com  Sat Jul 18 07:03:11 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sat, 18 Jul 2009 06:03:11 -0500
Subject: difference in printing to screen Mac / Windows
In-Reply-To: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com>
References: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com>
Message-ID: <4A61ABEF.6020002@tim.thechases.com>

> I notice a difference between running the following script on my Mac and on
> a PC:
> 
> from time import sleep
> for i in range(10):
>    print i,
>    sleep(2)
> 
> On my PC this prints a number every 2 seconds. This is the behavior I want.
> 
> On my Mac Python waits 10*2 = 20 seconds, and then prints 0 1 2 3 4 5 6 7 8
> 9

This sounds like a buffered vs. non-buffered output issue.  My 
guess would be that if you increased 10 to something larger, the 
output buffer would flush at various intervals.  The solution on 
the Mac (or other *nix-like OSes) would be to either start python 
in unbuffered mode:

   python -u mycode.py

Alternatively, you can force a flush of the output buffer at each 
iteration:

   import sys
   for i in range(10):
     print i
     sys.stdout.flush()
     sleep(2)

Lastly, you can force all standard-output in your program to be 
unbuffered without the "-u" parameter:

   sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)

Hope this helps,

-tkc




From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 07:21:32 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 12:21:32 +0100
Subject: Python graphics / imaging library
Message-ID: <sqn8j6xnm3.ln2@phoenix.fire>

Chaps,

what's the most appropriate (maintained) graphics library to use?  PIL seems
to have last been updated in 2006 http://www.pythonware.com/products/pil/
and GD seems to be even older.  Don't want to go down a dead end.

Pete

-- 
http://www.petezilla.co.uk


From motoom at xs4all.nl  Sat Jul 18 07:38:14 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Sat, 18 Jul 2009 13:38:14 +0200
Subject: Python graphics / imaging library
In-Reply-To: <sqn8j6xnm3.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>
Message-ID: <4A61B426.2090404@xs4all.nl>

Peter Chant wrote:

> what's the most appropriate (maintained) graphics library to use?  PIL seems
> to have last been updated in 2006 http://www.pythonware.com/products/pil/
> and GD seems to be even older.  Don't want to go down a dead end.

Contrary to organic material, software doesn't rot when it gets older.

PIL is pretty complete for the task it was designed to do, pretty 
debugged during the past years, and pretty much 'finished' -- it doesn't 
need frequent updates anymore.

Greetings,

-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 07:50:01 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 12:50:01 +0100
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
Message-ID: <9gp8j6xuh6.ln2@phoenix.fire>

Michiel Overtoom wrote:

> Peter Chant wrote:
> 
>> what's the most appropriate (maintained) graphics library to use?  PIL
>> seems to have last been updated in 2006
>> http://www.pythonware.com/products/pil/
>> and GD seems to be even older.  Don't want to go down a dead end.
> 
> Contrary to organic material, software doesn't rot when it gets older.
> 
> PIL is pretty complete for the task it was designed to do, pretty
> debugged during the past years, and pretty much 'finished' -- it doesn't
> need frequent updates anymore.
> 
> Greetings,
> 

No, it does not.  However, if PIL was updated last in 2006.  Python in 2009
has gone to version 3.1.  If PIL is compatible with 3.1 then I'm fine.  But
I don't want to have to stick with Python 2.5 as the rest of the world
moves on.

Pete


-- 
http://www.petezilla.co.uk


From benjamin.kaplan at case.edu  Sat Jul 18 08:26:22 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Sat, 18 Jul 2009 08:26:22 -0400
Subject: Python graphics / imaging library
In-Reply-To: <9gp8j6xuh6.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
Message-ID: <ec96e1390907180526y1d992820td83df38f41baaba7@mail.gmail.com>

On Sat, Jul 18, 2009 at 7:50 AM, Peter Chant <
REMpeteOVE at cappetezilla.italsco.uk> wrote:

> Michiel Overtoom wrote:
>
> > Peter Chant wrote:
> >
> >> what's the most appropriate (maintained) graphics library to use?  PIL
> >> seems to have last been updated in 2006
> >> http://www.pythonware.com/products/pil/
> >> and GD seems to be even older.  Don't want to go down a dead end.
> >
> > Contrary to organic material, software doesn't rot when it gets older.
> >
> > PIL is pretty complete for the task it was designed to do, pretty
> > debugged during the past years, and pretty much 'finished' -- it doesn't
> > need frequent updates anymore.
> >
> > Greetings,
> >
>
> No, it does not.  However, if PIL was updated last in 2006.  Python in 2009
> has gone to version 3.1.  If PIL is compatible with 3.1 then I'm fine.  But
> I don't want to have to stick with Python 2.5 as the rest of the world
> moves on.
>

The rest of the world hasn't moved on yet. Most people are still using
Python 2.6 and the 2.x series will continue to be actively developed for
another couple years.


> Pete
>
>
> --
> http://www.petezilla.co.uk
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/325c1520/attachment.html>

From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 08:30:02 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 13:30:02 +0100
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
Message-ID: <arr8j6xn0c.ln2@phoenix.fire>

Peter Chant wrote:


> 
> No, it does not.  However, if PIL was updated last in 2006.  Python in
> 2009
> has gone to version 3.1.  If PIL is compatible with 3.1 then I'm fine. 
> But I don't want to have to stick with Python 2.5 as the rest of the world
> moves on.

BTW, this was not a critisism of PIL or GD, rather what do people generally
use now?

-- 
http://www.petezilla.co.uk


From motoom at xs4all.nl  Sat Jul 18 08:41:36 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Sat, 18 Jul 2009 14:41:36 +0200
Subject: Python graphics / imaging library
In-Reply-To: <arr8j6xn0c.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>	<mailman.3355.1247917094.8015.python-list@python.org>	<9gp8j6xuh6.ln2@phoenix.fire>
	<arr8j6xn0c.ln2@phoenix.fire>
Message-ID: <4A61C300.9070503@xs4all.nl>

Peter Chant wrote:

> what do people generally use now?

I can only speak for myself... I use PIL ;-)

Greetings,



From maxerickson at gmail.com  Sat Jul 18 08:54:50 2009
From: maxerickson at gmail.com (Max Erickson)
Date: Sat, 18 Jul 2009 12:54:50 +0000 (UTC)
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
Message-ID: <Xns9C4C5AA8CF713maxericksongmailcom@80.91.229.13>

Peter Chant <REMpeteOVE at CAPpetezilla.ITALSco.uk> wrote:

> No, it does not.  However, if PIL was updated last in 2006. 
> Python in 2009 has gone to version 3.1.  If PIL is compatible
> with 3.1 then I'm fine.  But I don't want to have to stick with
> Python 2.5 as the rest of the world moves on.
> 
> Pete
> 
> 

Various messages to the Image-SIG mailing list indicate that support 
for 3.x is coming after a release of 1.1.7:

http://mail.python.org/pipermail/image-sig/2009-March/005498.html

More here:

http://mail.python.org/pipermail/image-sig/2009-March/thread.html

More recent months contain updates to the status of 1.1.7, it is 
headed towards a release. Preliminary tarballs and binaries are 
available on effbot.org:

http://effbot.org/downloads/#imaging
http://effbot.org/downloads/#pil


max



From rhodri at wildebst.demon.co.uk  Sat Jul 18 09:17:12 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sat, 18 Jul 2009 14:17:12 +0100
Subject: Beginners question
In-Reply-To: <4A612D74.80908@gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
	<4A612D74.80908@gmail.com>
Message-ID: <op.uw9luyxka8ncjz@gnudebst>

On Sat, 18 Jul 2009 03:03:32 +0100, gabrielmonnerat  
<gabrielmonnerat at gmail.com> wrote:

> Ronn Ross wrote:
>> How do you define a global variable in a class. I tried this with do  
>> success:
>> class ClassName:
>>     global_var = 1
>>        def some_methos():
>>         print global_var
>>
>> This doesn't work. What am I doing wrong?
> You need pass "self" to the function and "global_var" needs be called  
> with self.
>
> class ClassName:
>     global_var = 1
>        def some_methos(self):
>         print self.global_var

If the OP really wants global_var to be global to the class, this
approach will only work as long as he never assigns to self.global_var.

The terminology is a bit confusing here.  "Global variables" refers to
variables which are global to an entire module, ones that you would
use "global" to declare inside a function.  Something like this:

x = 5
def set_x(y):
     global x
     x = y

set_x(3)
print x

...gives the result "3"

The idea of defining a global variable in a class is a bit of a
nonsense, since globals exist for the entire module.  There are,
however, variables that exist and are the same for every instance
of a class, or "class attributes" as they are normally called.  You
use them either by assignment in the class definition, or in a
method by prefixing them with the class name.

class ClassName:
     global_var = 1
     def some_method(self):
         print ClassName.global_var
         ClassName.global_var = 2

"Instance attributes", the ones prefixed by "self", are what get
used for most purposes.  These are separate for each different
instance of the class.

class ClassName:
     def __init__(self, val):
        self.var = val

a = ClassName(1)
b = ClassName(2)

print a.var, b.var

...gives the result "1 2"

The wrinkle is that if you read from an instance attribute that
doesn't exist, Python will use a class attribute of the same name
if there is one.  This is often exploited for setting default
values.  Beware, though: the moment you assign, an instance
attribute is created -- the underlying class attribute is *not*
changed.

class ClassName:
     global_var = 1
     def some_method(self):
         self.global_var = 2

a = ClassName()
b = ClassName()
b.some_method()
print a.global_var, b.global_var

...gives the result "1 2" again!

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From dstanek at dstanek.com  Sat Jul 18 09:41:13 2009
From: dstanek at dstanek.com (David Stanek)
Date: Sat, 18 Jul 2009 09:41:13 -0400
Subject: Python import Error
In-Reply-To: <8ca278430907180014k460f3798mafef6fc59379677b@mail.gmail.com>
References: <8ca278430907180014k460f3798mafef6fc59379677b@mail.gmail.com>
Message-ID: <de32cc030907180641l367f9406m36c5ce4ff0bf4ee@mail.gmail.com>

On Sat, Jul 18, 2009 at 3:14 AM, Kalyan
Chakravarthy<kalyanchakravarthy at hyit.com> wrote:
> Hi All,
> ?????????????????? I am using Python 2.6, MySQL 4.0 , I have successfully
> Instaled MySQLdb (MySQL-python-1.2.3c1.win32-py2.6) in my system. I tested
> through command prompt with "import MySQLdb ", its not shwing any errors
> (means its instaled successfully), I set Eneceranment variable for Python
>
> I? am running simple application with import "MySQLdb" to get the connection
> to MySQL, But its throwing "No module named MySQLdb", Please any one tell me
> what couled be the reasion
>
> is there any version miss match with python and MySQL ?
>
> Since last 3days I am strugling on this
>

Off the top of my head I would say that maybe you are using one python
binary from the command-line and another in your script or possibly
your python path is foobar.

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From tjcrone at gmail.com  Sat Jul 18 10:34:11 2009
From: tjcrone at gmail.com (Timothy Crone)
Date: Sat, 18 Jul 2009 10:34:11 -0400
Subject: Unpack Expects the Wrong Number of Bytes
Message-ID: <78926b920907180734p7363af24v7f81f425cdd6d972@mail.gmail.com>

Hello,

I have noticed that for certain format strings, struct.unpack expects
the wrong number of bytes. For example, this works fine

header = "4si4s4si2h2i3h4s"
data = list(unpack(header,f.read(42)))

however, this

header = "4si4s4si2h2i3h4si"
data = list(unpack(header,f.read(46)))

returns the following error:

struct.error: unpack requires a string argument of length 48

So even though my format string includes an additional 4-byte integer,
unpack is expecting 6 additional bytes. Here's a simpler example:

This works:

header = "s"
data = list(unpack(header,f.read(1)))

however this:

header = "si"
data = list(unpack(header,f.read(5)))

throws

struct.error: unpack requires a string argument of length 8

So unpack expects 7 additional bytes when an integer is added to the
format string. Does anyone know what is going on? I am using Debian
stable, so my Python version is 2.5.2. But I have replicated this with
2.6.2. Here's my proc/version: Linux version 2.6.30-bpo.1-amd64
(Debian 2.6.30-1~bpo50+1) (nobse at debian.org) (gcc version 4.3.2
(Debian 4.3.2-1.1) ) #1 SMP Fri Jun 26 09:41:55 UTC 2009

Any help would be greatly appreciated.

Cheers,
Tim


From aahz at pythoncraft.com  Sat Jul 18 10:44:29 2009
From: aahz at pythoncraft.com (Aahz)
Date: 18 Jul 2009 07:44:29 -0700
Subject: setup.py not found
References: <3be2bdce-680d-4b32-ad0c-ef46caf556e9@f10g2000vbf.googlegroups.com>
Message-ID: <h3sn4d$fc3$1@panix3.panix.com>

In article <3be2bdce-680d-4b32-ad0c-ef46caf556e9 at f10g2000vbf.googlegroups.com>,
Larry.Martell at gmail.com <Larry.Martell at gmail.com> wrote:
>
>I'm trying to install a package (cx_Oracle) on a mac running 10.5.7.
>I've done this on other platforms, but never on a mac. I followed the
>instructions given, but when I try and run setup I get:
>
>Apollo:instantclient_10_2 user$ python setup.py build
>/System/Library/Frameworks/Python.framework/Versions/2.5/Resources/
>Python.app/Contents/MacOS/Python: can't open file 'setup.py': [Errno
>2] No such file or directory
>
>Is there something else I have to install first to have this?

Do you have a setup.py in the current working directory?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From sjmachin at lexicon.net  Sat Jul 18 10:47:15 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sat, 18 Jul 2009 07:47:15 -0700 (PDT)
Subject: Unpack Expects the Wrong Number of Bytes
References: <mailman.3364.1247927673.8015.python-list@python.org>
Message-ID: <34a7b901-4d33-469a-8b35-5ac1f30304fa@i18g2000pro.googlegroups.com>

On Jul 19, 12:34?am, Timothy Crone <tjcr... at gmail.com> wrote:
> Hello,
>
> I have noticed that for certain format strings, struct.unpack expects
> the wrong number of bytes.
[snip]
> header = "si"
> data = list(unpack(header,f.read(5)))
>
> throws
>
> struct.error: unpack requires a string argument of length 8
>
> So unpack expects 7 additional bytes when an integer is added to the
> format string. Does anyone know what is going on?

Alignment. 1 byte for the "s", 3 pad bytes to get to the next "i"
boundary, 4 bytes for the "i".

http://docs.python.org/library/struct.html
Then Ctrl-F search for "align"

Choose a prefix character whose MO matches the struct that you need to
work with.

Cheers,
John


From python at mrabarnett.plus.com  Sat Jul 18 10:53:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 18 Jul 2009 15:53:18 +0100
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907171948l35e73c14gf02bc3c6ef11d493@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>	<mailman.3275.1247836630.8015.python-list@python.org>	<02707804$0$5185$c3e8da3@news.astraweb.com>	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>	<h3qs5u$1cr$1@ger.gmane.org>	<2d56febf0907171507y75f6436ete75cb3f748ee838d@mail.gmail.com>	<4A611D89.7040603@ieee.org>	<2d56febf0907171947s6a4a010fp124146d54d560bf4@mail.gmail.com>
	<2d56febf0907171948l35e73c14gf02bc3c6ef11d493@mail.gmail.com>
Message-ID: <4A61E1DE.8010300@mrabarnett.plus.com>

Xavier Ho wrote:
> Darn it.
> 
> On Sat, Jul 18, 2009 at 8:55 AM, Dave Angel <davea at ieee.org 
> <mailto:davea at ieee.org>> wrote:
> 
> 
>     You don't need a counter.  len() will tell you the size of the list
>     of primes.
> 
> 
> Does len() go through and count by itself, or does it actually keep 
> track of the size and just return the memory? I always thought it would 
> go through and count, which may take some time. I could be wrong. 
> 
[snip]
Lists (and strings, tuples, dicts and sets) know how many items they
contain.


From rridge at csclub.uwaterloo.ca  Sat Jul 18 10:55:53 2009
From: rridge at csclub.uwaterloo.ca (Ross Ridge)
Date: Sat, 18 Jul 2009 10:55:53 -0400
Subject: Unpack Expects the Wrong Number of Bytes
References: <mailman.3364.1247927673.8015.python-list@python.org>
Message-ID: <h3snpp$ug6$1@rumours.uwaterloo.ca>

Timothy Crone  <tjcrone at gmail.com> wrote:
>header = "s"
>data = list(unpack(header,f.read(1)))
>
>however this:
>
>header = "si"
>data = list(unpack(header,f.read(5)))
>
>throws
>
>struct.error: unpack requires a string argument of length 8
>
>So unpack expects 7 additional bytes when an integer is added to the
>format string. Does anyone know what is going on?

It's adding pad bytes so that the format matches the equivilent C
structure on your machine.  You should use either the "<" little-endian
or the ">" big-endian prefix depending on the byte order used in the file
you're trying to unpack.  You can also use the "=" native byte-order
flag if endianness of the file format changes according to the machine
your Python program runs on.  If you use any of these flags, no extra
padding will be inserted.

				Ross Ridge

-- 
 l/  //	  Ross Ridge -- The Great HTMU
[oo][oo]  rridge at csclub.uwaterloo.ca
-()-/()/  http://www.csclub.uwaterloo.ca/~rridge/ 
 db  //	  


From alan.isaac at gmail.com  Sat Jul 18 11:31:46 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sat, 18 Jul 2009 15:31:46 GMT
Subject: invoke method on many instances
In-Reply-To: <02701d35$0$5185$c3e8da3@news.astraweb.com>
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <CVl8m.141$MA3.16@nwrddc02.gnilink.net>

> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>> def apply2(itr, methodname, *args, **kwargs):
>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>     for item in itr:
>>         f(item)


On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
> for obj in objects:
>     getattr(obj, methodname)(*args, **kwargs)


Are there any obvious considerations in choosing
between those two?



> See also these recipes from the "Python Cookbook": 
> http://code.activestate.com/recipes/52289/
> http://code.activestate.com/recipes/87370/

Interesting.

Thanks,
Alan


From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 11:41:33 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 16:41:33 +0100
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
	<mailman.3361.1247921706.8015.python-list@python.org>
Message-ID: <d279j6x8r6.ln2@phoenix.fire>

Max Erickson wrote:

> More recent months contain updates to the status of 1.1.7, it is
> headed towards a release. Preliminary tarballs and binaries are
> available on effbot.org:
> 
> http://effbot.org/downloads/#imaging
> http://effbot.org/downloads/#pil

Excellent.  From a very brief look it seems like it will be quite simple to
use.

Pete


-- 
http://www.petezilla.co.uk


From tkermode at gmail.com  Sat Jul 18 11:50:44 2009
From: tkermode at gmail.com (Tom Kermode)
Date: Sat, 18 Jul 2009 16:50:44 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2rnoe$26s$5@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <da7092380907180850l5e2f62b8ic355463a8e2e5d9d@mail.gmail.com>

Maybe the IDE is the best place to warn you of something like that.

You could have an IDE where you specify which language you're more
familiar with and then have it display warnings likely to be relevant
to you.  People could collaborate to add support for gradually more
niche languages.

Python could continue to work the way it was designed to and people
documenting python wouldn't have to worry about this kind of issue. :)

2009/7/6 Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand>:
> I wonder how many people have been tripped up by the fact that
>
> ? ?++n
>
> and
>
> ? ?--n
>
> fail silently for numeric-valued n.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.kiloday.com
http://www.fourstopspast.com


From marcusw at cox.net  Sat Jul 18 11:58:47 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 18 Jul 2009 11:58:47 -0400
Subject: Python graphics / imaging library
In-Reply-To: <d279j6x8r6.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
	<mailman.3361.1247921706.8015.python-list@python.org>
	<d279j6x8r6.ln2@phoenix.fire>
Message-ID: <h3srfn$h23$1@adenine.netfront.net>

On 7/18/2009 11:41 AM, Peter Chant wrote:
> Max Erickson wrote:
> 
>> More recent months contain updates to the status of 1.1.7, it is
>> headed towards a release. Preliminary tarballs and binaries are
>> available on effbot.org:
>>
>> http://effbot.org/downloads/#imaging
>> http://effbot.org/downloads/#pil
> 
> Excellent.  From a very brief look it seems like it will be quite simple to
> use.
> 
> Pete
> 
> 
Yes, it was fun to work with (for me at least).

Marcus


From gnarlodious at gmail.com  Sat Jul 18 12:32:18 2009
From: gnarlodious at gmail.com (Gnarlodious)
Date: Sat, 18 Jul 2009 09:32:18 -0700 (PDT)
Subject: Rus Python script interactively
Message-ID: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>

In an interactive session (I am using iPython), what is the most
elegant way to run a Python script from Terminal? Right now I am
saying:

import subprocess
subprocess.call("python /path/to/scriptname.py", shell=True)

But I am calling a shell process and I'd rather not. The script just
runs, no inputs are needed. Is there a more Pythonesque method?

-- Gnarlie
http://Gnarlodious.com/


From deets at nospam.web.de  Sat Jul 18 12:39:53 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 18 Jul 2009 18:39:53 +0200
Subject: Rus Python script interactively
In-Reply-To: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <7cec6pF26munvU1@mid.uni-berlin.de>

Gnarlodious schrieb:
> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?

If it's in the path, you can just import it. That will of course only be 
possible once per ipython-session.

Diez


From lie.1296 at gmail.com  Sat Jul 18 12:55:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 19 Jul 2009 02:55:49 +1000
Subject: Rus Python script interactively
In-Reply-To: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <h3suqn$ifa$1@ger.gmane.org>

Gnarlodious wrote:
> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?
> 
> -- Gnarlie
> http://Gnarlodious.com/

IMHO, starting a new terminal and runs the script from there.
Or quitting/pausing the current interactive session and run it like
normal python scripts.

Alternatively, you may also want to look at `execfile` built-in function.
>>> execfile('myscript.py', {}, {})



From marcusw at cox.net  Sat Jul 18 13:04:07 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 18 Jul 2009 13:04:07 -0400
Subject: Rus Python script interactively
In-Reply-To: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <h3sva8$1kn3$1@adenine.netfront.net>

On 7/18/2009 12:32 PM, Gnarlodious wrote:
> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?
> 
> -- Gnarlie
> http://Gnarlodious.com/
You could put the code of the script in a main() function and have an if 
__name__ == '__main__': around the internal call. That way, it will 
still run the code if you run it normally, and you can also run it 
several times from the interactive session, ie:
file you want to run:
{{{
def somefunction():
	print 'hello world'

somefunction()
}}}
file after modifications:
{{{
def somefunction():
	print 'hello world'

def main():
	somefunction()

if __name__ == '__main__': #only true if the file is being run normally, 
not imported.
	main()
}}}
Both of those, if run normally, will print "hello world". If the first 
one is imported, it will run once and not me runnable in that session 
again. If the second one is imported, it will not do anything until you 
call the main() function, and then you can call it again as many times 
as you want:
{{{
 >>> import thefile
 >>> for i in range(5):
... 	thefile.main()
...
hello world
hello world
hello world
hello world
hello world
 >>> exit()
}}}
Hope this helps you!

Marcus


From __peter__ at web.de  Sat Jul 18 13:13:17 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 19:13:17 +0200
Subject: Rus Python script interactively
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <h3svqt$e8s$02$1@news.t-online.com>

Gnarlodious wrote:

> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?

After a quick glance over ipython's %quickref:

In [1]: !mkdir -p path/to

In [2]: !echo 'print "works!"' > path/to/scriptname.py

In [3]: %run path/to/scriptname.py
works!




From timphotoman at gmail.com  Sat Jul 18 13:25:11 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 13:25:11 -0400
Subject: python command running old version
Message-ID: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>

My brain is running in n00b mode this morning...must find coffee.

I upgraded python this morning and entering python from the command
line runs the old version.

Just looked and it appears the old version is in /usr/bin while the
new one is in /usr/local/bin/

Besides changing the path order, how do I ensure it runs the new
version? I'm sure I'll bang my head on the desk in shame as soon as
I'm reminded.

Thanks.


From clp2 at rebertia.com  Sat Jul 18 13:26:40 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 10:26:40 -0700
Subject: python command running old version
In-Reply-To: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
Message-ID: <50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>

On Sat, Jul 18, 2009 at 10:25 AM, Tim Edwards<timphotoman at gmail.com> wrote:
> My brain is running in n00b mode this morning...must find coffee.
>
> I upgraded python this morning and entering python from the command
> line runs the old version.

Which OS? How did you install it?

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Sat Jul 18 13:32:25 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 10:32:25 -0700
Subject: Auto Send URL
In-Reply-To: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>
References: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>
Message-ID: <50697b2c0907181032x6f0029dfs304a345ca2835690@mail.gmail.com>

On Fri, Jul 17, 2009 at 6:02 AM, Victor Subervi<victorsubervi at gmail.com> wrote:
> Hi;
> I am trying to script code that automatically sends a Web site visitor to an
> URL. Specifically, when they enter a value in a search box, I have that form
> sent to a script that writes an URL acceptable to Google, then I want to
> send the visitor off without him having to click another button. How do I do
> this?

Send back a webpage with a Refresh meta tag:

<html>
    <head>
    <meta http-equiv="Refresh" content="0; url=http://YOUR-URL-HERE/">
    </head>
</html>

Cheers,
Chris
-- 
http://blog.rebertia.com


From lists at cheimes.de  Sat Jul 18 13:33:48 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sat, 18 Jul 2009 19:33:48 +0200
Subject: python command running old version
In-Reply-To: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
Message-ID: <h3t11s$nqe$1@ger.gmane.org>

Tim Edwards wrote:
> Besides changing the path order, how do I ensure it runs the new
> version? I'm sure I'll bang my head on the desk in shame as soon as
> I'm reminded.

hash -r

Christian



From timphotoman at gmail.com  Sat Jul 18 13:37:50 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 13:37:50 -0400
Subject: python command running old version
In-Reply-To: <50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
	<50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
Message-ID: <ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>

> Which OS? How did you install it?

Sorry (see I need that coffee)

Installed on redhat from source


From timphotoman at gmail.com  Sat Jul 18 13:54:31 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 13:54:31 -0400
Subject: python command running old version
In-Reply-To: <h3t11s$nqe$1@ger.gmane.org>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
	<h3t11s$nqe$1@ger.gmane.org>
Message-ID: <ad7b98710907181054q5cf8e045r5908252f5740a6ed@mail.gmail.com>

>> Besides changing the path order, how do I ensure it runs the new
>> version? I'm sure I'll bang my head on the desk in shame as soon as
>> I'm reminded.
>
> hash -r

Thanks.


From lie.1296 at gmail.com  Sat Jul 18 13:58:13 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 19 Jul 2009 03:58:13 +1000
Subject: python command running old version
In-Reply-To: <ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>	<50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
	<ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>
Message-ID: <h3t2fn$rhm$1@ger.gmane.org>

Tim Edwards wrote:
>> Which OS? How did you install it?
> 
> Sorry (see I need that coffee)
> 
> Installed on redhat from source

You should consult the distro's (i.e. RedHat's) documentation/mailing
list about changing the default python interpreter. In most cases, you
will need to make sure all python-related packages are compatible with
the new python version. In popular distros, there should be a script
that will do that for you.



From akhilanger at gmail.com  Sat Jul 18 14:20:20 2009
From: akhilanger at gmail.com (akhil1988)
Date: Sat, 18 Jul 2009 11:20:20 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <pan.2009.07.17.07.20.15.547000@nowhere.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<pan.2009.07.17.07.20.15.547000@nowhere.com>
Message-ID: <24550497.post@talk.nabble.com>


Thanks Nobody-38, it solved my problem immediately.

--Thanks Again,
Akhil

Nobody-38 wrote:
> 
> On Thu, 16 Jul 2009 20:26:39 -0700, akhil1988 wrote:
> 
>> Well, you were write: unintentionally I removed strip(). But the problem
>> does
>> not ends here:
>> 
>> I get this error now:
>> 
>>  File "./temp.py", line 488, in <module>
>>     main()
>>   File "./temp.py", line 475, in main
>>     for line in sys.stdin:
>>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>>     (result, consumed) = self._buffer_decode(data, self.errors, final)
>> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2:
>> invalid
>> data
>> 
>> for this line:
>> ?
> 
> Right. You're running in a locale whose encoding is UTF-8, but feeding
> data which isn't valid UTF-8 to stdin. If you want to use data with a
> different encoding, you need to replace sys.stdin, e.g.:
> 
> import sys
> import io
> sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding = 'iso-8859-1')
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24550497.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From akhilanger at gmail.com  Sat Jul 18 14:25:53 2009
From: akhilanger at gmail.com (akhil1988)
Date: Sat, 18 Jul 2009 11:25:53 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <gsKdncY9AMiQKP3XnZ2dnUVZ_hudnZ2d@pdx.net>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<gsKdncY9AMiQKP3XnZ2dnUVZ_hudnZ2d@pdx.net>
Message-ID: <24550540.post@talk.nabble.com>


Thanks David, it solved my problem immediately. 

I will follow your advise from next time but honestly I am new to python
with not much knowledge about text formats. And the main portion of my
project was not to deal with these, so I just wanted to get this solved as I
was already struck at this for 2 days. If you think I am wrong in my
approach to getting problems solved, please let me know. Your advise would
be helpful in future for me.

--Thanks Again,
Akhil 

Scott David Daniels wrote:
> 
> akhil1988 wrote:
> <mis-ordered reply, bits shown below>>
>> Nobody-38 wrote:
>>> On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:
> ...
>>>>> In Python 3 you can't decode strings because they are Unicode strings
>>>>> and it doesn't make sense to decode a Unicode string. You can only
>>>>> decode encoded things which are byte strings. So you are mixing up
>>>>> byte
>>>>> strings and Unicode strings.
>>>> ... I read a byte string from sys.stdin which needs to converted to
>>>> unicode
>>>> string for further processing.
>>> In 3.x, sys.stdin (stdout, stderr) are text streams, which means that
>>> they
>>> read and write Unicode strings, not byte strings.
>>>
>>>> I cannot just remove the decode statement and proceed?
>>>> This is it what it looks like:
>>>>     for line in sys.stdin:
>>>>         line = line.decode('utf-8').strip()
>>>>         if line == '<page>': #do something here
>>>>         ....
>>>> If I remove the decode statement, line == '<page>' never gets true. 
>>> Did you inadvertently remove the strip() as well?
>> ... unintentionally I removed strip()....
>> I get this error now:
>>  File "./temp.py", line 488, in <module>
>>     main()
>>   File "./temp.py", line 475, in main
>>     for line in sys.stdin:
>>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>>     (result, consumed) = self._buffer_decode(data, self.errors, final)
>> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2:
>> invalid
>> data
> 
> (1) Do not top post.
> (2) Try to fully understand the problem and proposed solution, rather
>      than trying to get people to tell you just enough to get your code
>      going.
> (3) The only way sys.stdin can possibly return unicode is to do some
>      decoding of its own.  your job is to make sure it uses the correct
>      decoding.  So, if you know your source is always utf-8, try
>      something like:
> 
>      import sys
>      import io
> 
>      sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding='utf8')
> 
>      for line in sys.stdin:
>          line = line.strip()
>          if line == '<page>':
>              #do something here
>          ....
> 
> --Scott David Daniels
> Scott.Daniels at Acm.Org
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24550540.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From timphotoman at gmail.com  Sat Jul 18 15:35:19 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 15:35:19 -0400
Subject: python command running old version
In-Reply-To: <h3t2fn$rhm$1@ger.gmane.org>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
	<50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
	<ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>
	<h3t2fn$rhm$1@ger.gmane.org>
Message-ID: <ad7b98710907181235p4bd64c44j288c7642df4cad65@mail.gmail.com>

> You should consult the distro's (i.e. RedHat's) documentation/mailing
> list about changing the default python interpreter. In most cases, you
> will need to make sure all python-related packages are compatible with
> the new python version. In popular distros, there should be a script
> that will do that for you.

Thanks, I'll look into that.


From sgm at objexx.com  Sat Jul 18 16:49:42 2009
From: sgm at objexx.com (SK)
Date: Sat, 18 Jul 2009 13:49:42 -0700 (PDT)
Subject: multiprocessing and freezing on Windows
References: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>
	<a205db1d-a801-4774-bfa1-124a723ea71b@p36g2000prn.googlegroups.com> 
	<mailman.2670.1246863247.8015.python-list@python.org>
Message-ID: <015ab41f-7433-4136-8b9c-809f96ae6384@o13g2000vbl.googlegroups.com>

Thanks Gabriel.

Posted as: http://bugs.python.org/issue6461

The multiprocessing author has tentatively confirmed the bug.


From twgray2007 at gmail.com  Sat Jul 18 17:33:48 2009
From: twgray2007 at gmail.com (twgray)
Date: Sat, 18 Jul 2009 14:33:48 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python socket?
Message-ID: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>

I am attempting to send a jpeg image file created on an embedded
device over a wifi socket to a Python client running on a Linux pc
(Ubuntu).  All works well, except I don't know, on the pc client side,
what the file size is?  The following is a snippet:

[code]
        f = open("frame.jpg",mode = 'wb')
       while True:
            data = self.s.recv(MAXPACKETLEN)
            if len(data) == 0:
                break
            recvd += len(data)
            f.write(data)
        f.close()
[end]

It appears to be locking up in  'data=self.s.recv(MAXPACKETLEN)' on
the final packet, which will always be less than MAXPACKETLEN.

I guess my question is, how do I detect end of data on the client side?


From irmen.NOSPAM at xs4all.nl  Sat Jul 18 17:43:47 2009
From: irmen.NOSPAM at xs4all.nl (Irmen de Jong)
Date: Sat, 18 Jul 2009 23:43:47 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
Message-ID: <4a624251$0$191$e4fe514c@news.xs4all.nl>

twgray wrote:
> I am attempting to send a jpeg image file created on an embedded
> device over a wifi socket to a Python client running on a Linux pc
> (Ubuntu).  All works well, except I don't know, on the pc client side,
> what the file size is?  

You don't. Sockets are just endless streams of bytes. You will have to design some form 
of 'wire protocol' that includes the length of the message that is to be read.
For instance a minimalistic protocol could be the following:
Send 4 bytes that contain the length (an int) then the data itself. The client reads 4 
bytes, decodes it into the integer that tells it the length, and then reads the correct 
amount of bytes from the socket.


--irmen


From gnarlodious at gmail.com  Sat Jul 18 17:48:24 2009
From: gnarlodious at gmail.com (Gnarlodious)
Date: Sat, 18 Jul 2009 14:48:24 -0700 (PDT)
Subject: Rus Python script interactively
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
	<h3svqt$e8s$02$1@news.t-online.com>
Message-ID: <0814d92c-46bf-4421-88ea-499cb82a0be8@w41g2000yqb.googlegroups.com>

Thanks for all the suggestions! The last solution is the one I was
ooking for, I am really starting to like iPython. Learning all kinds
of new tricks!.

-- Gnarlie


From tycho at tycho.ws  Sat Jul 18 17:52:41 2009
From: tycho at tycho.ws (Tycho Andersen)
Date: Sat, 18 Jul 2009 16:52:41 -0500
Subject: How to receive a data file of unknown length using a python 
	socket?
In-Reply-To: <4a624251$0$191$e4fe514c@news.xs4all.nl>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
Message-ID: <49b3a7400907181452t3f87ee39n17b3dc15c3426d34@mail.gmail.com>

On Sat, Jul 18, 2009 at 4:43 PM, Irmen de Jong<irmen.NOSPAM at xs4all.nl> wrote:
> twgray wrote:
>>
>> I am attempting to send a jpeg image file created on an embedded
>> device over a wifi socket to a Python client running on a Linux pc
>> (Ubuntu). ?All works well, except I don't know, on the pc client side,
>> what the file size is?
>
> You don't. Sockets are just endless streams of bytes. You will have to
> design some form of 'wire protocol' that includes the length of the message
> that is to be read.
> For instance a minimalistic protocol could be the following:
> Send 4 bytes that contain the length (an int) then the data itself. The
> client reads 4 bytes, decodes it into the integer that tells it the length,
> and then reads the correct amount of bytes from the socket.

Exactly, sending the length first is the only way to know ahead of
time. Alternatively, if you know what the end of the data looks like,
you can look for that 'flag' as well, and stop trying to recv() after
that.

Some things that may be useful, though, are socket.settimeout() and
socket.setblocking(). More information is availible in the docs:
http://docs.python.org/library/socket.html.

You need to be careful with this, though, since network latency may
cause problems. Using these methods will keep your program from
sitting in recv() forever, though.

\t
--
http://tycho.ws


From twgray2007 at gmail.com  Sat Jul 18 18:04:41 2009
From: twgray2007 at gmail.com (twgray)
Date: Sat, 18 Jul 2009 15:04:41 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
Message-ID: <243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>

On Jul 18, 4:43?pm, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
> twgray wrote:
> > I am attempting to send a jpeg image file created on an embedded
> > device over a wifi socket to a Python client running on a Linux pc
> > (Ubuntu). ?All works well, except I don't know, on the pc client side,
> > what the file size is? ?
>
> You don't. Sockets are just endless streams of bytes. You will have to design some form
> of 'wire protocol' that includes the length of the message that is to be read.
> For instance a minimalistic protocol could be the following:
> Send 4 bytes that contain the length (an int) then the data itself. The client reads 4
> bytes, decodes it into the integer that tells it the length, and then reads the correct
> amount of bytes from the socket.
>
> --irmen

Thanks for the reply.  But, now I have a newbie Python question.  If I
send a 4 byte address from the embedded device, how do I convert that,
in Python, to a 4 byte, or long, number?


From tjreedy at udel.edu  Sat Jul 18 18:30:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 18 Jul 2009 18:30:08 -0400
Subject: invoke method on many instances
In-Reply-To: <CVl8m.141$MA3.16@nwrddc02.gnilink.net>
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>	<02701d35$0$5185$c3e8da3@news.astraweb.com>
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
Message-ID: <h3tidf$23k$1@ger.gmane.org>

Alan G Isaac wrote:
>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>> def apply2(itr, methodname, *args, **kwargs):
>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>     for item in itr:
>>>         f(item)
> 
> 
> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>> for obj in objects:
>>     getattr(obj, methodname)(*args, **kwargs)
> 
> 
> Are there any obvious considerations in choosing
> between those two?

I would use the straightforward getattr idiom.



From rickbking at comcast.net  Sat Jul 18 18:30:52 2009
From: rickbking at comcast.net (Rick King)
Date: Sat, 18 Jul 2009 18:30:52 -0400
Subject: uniicode and executing a process with subprocess.call, or os.system
Message-ID: <4A624D1C.5010503@comcast.net>

Hello,
I want to copy files using subprocess.call or os.system where the file 
names are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. 
Windows stores all the file names in unicode so they are displayed ok in 
explorer, and I can read them into my program with listdir(u'.'), etc. 
and work with the names in the program.

os.rename()

can be used to rename such files successfully.

But I want to be able to copy files using:

cmdstr = u'copy' +u' /Y "'+pair[0]+u'" "'+pair[1]+u'"\n'
cmdstr = cmdstr.encode(sys.getfilesystemencoding())
try: retcode = sp.call(cmdstr, shell=True) #SP=SUBPROCESS

but the encoding can't handle all the characters and so the file isn't 
found to be copied. sp.call() returns 1. 'mbcs' encoding doesn't work 
either. 'utf-8' doesn't work.

I am very confused about unicode. Can someone point me in the right 
direction?

windows xp sp2
python 2.6.2 unicode

Thanks!
Rick King
Southfield MI






From python at mrabarnett.plus.com  Sat Jul 18 19:05:48 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 00:05:48 +0100
Subject: How to receive a data file of unknown length using a python 
	socket?
In-Reply-To: <243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
Message-ID: <4A62554C.3040100@mrabarnett.plus.com>

twgray wrote:
> On Jul 18, 4:43 pm, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
>> twgray wrote:
>>> I am attempting to send a jpeg image file created on an embedded
>>> device over a wifi socket to a Python client running on a Linux pc
>>> (Ubuntu).  All works well, except I don't know, on the pc client side,
>>> what the file size is?  
>> You don't. Sockets are just endless streams of bytes. You will have to design some form
>> of 'wire protocol' that includes the length of the message that is to be read.
>> For instance a minimalistic protocol could be the following:
>> Send 4 bytes that contain the length (an int) then the data itself. The client reads 4
>> bytes, decodes it into the integer that tells it the length, and then reads the correct
>> amount of bytes from the socket.
>>
> Thanks for the reply.  But, now I have a newbie Python question.  If I
> send a 4 byte address from the embedded device, how do I convert that,
> in Python, to a 4 byte, or long, number?

If you send the length as 4 bytes then you'll have to decide whether
it's big-endian or little-endian. An alternative is to send the length
as characters, terminated by, say, '\n' or chr(0).


From clp2 at rebertia.com  Sat Jul 18 19:06:51 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 16:06:51 -0700
Subject: uniicode and executing a process with subprocess.call, or 
	os.system
In-Reply-To: <4A624D1C.5010503@comcast.net>
References: <4A624D1C.5010503@comcast.net>
Message-ID: <50697b2c0907181606n2af8577ew3ad178f0463fa2d8@mail.gmail.com>

On Sat, Jul 18, 2009 at 3:30 PM, Rick King<rickbking at comcast.net> wrote:
> Hello,
> I want to copy files using subprocess.call or os.system where the file names
> are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. Windows
> stores all the file names in unicode so they are displayed ok in explorer,
> and I can read them into my program with listdir(u'.'), etc. and work with
> the names in the program.

You should try one of the copying functions in the shutil module
instead, it'll be much simpler than using subprocess:
http://docs.python.org/library/shutil.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From python at mrabarnett.plus.com  Sat Jul 18 19:07:12 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 00:07:12 +0100
Subject: uniicode and executing a process with subprocess.call,
	or os.system
In-Reply-To: <4A624D1C.5010503@comcast.net>
References: <4A624D1C.5010503@comcast.net>
Message-ID: <4A6255A0.20804@mrabarnett.plus.com>

Rick King wrote:
> Hello,
> I want to copy files using subprocess.call or os.system where the file 
> names are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. 
> Windows stores all the file names in unicode so they are displayed ok in 
> explorer, and I can read them into my program with listdir(u'.'), etc. 
> and work with the names in the program.
> 
> os.rename()
> 
> can be used to rename such files successfully.
> 
> But I want to be able to copy files using:
> 
> cmdstr = u'copy' +u' /Y "'+pair[0]+u'" "'+pair[1]+u'"\n'
> cmdstr = cmdstr.encode(sys.getfilesystemencoding())
> try: retcode = sp.call(cmdstr, shell=True) #SP=SUBPROCESS
> 
> but the encoding can't handle all the characters and so the file isn't 
> found to be copied. sp.call() returns 1. 'mbcs' encoding doesn't work 
> either. 'utf-8' doesn't work.
> 
> I am very confused about unicode. Can someone point me in the right 
> direction?
> 
> windows xp sp2
> python 2.6.2 unicode
> 
Use the shutil module.


From aahz at pythoncraft.com  Sat Jul 18 19:18:22 2009
From: aahz at pythoncraft.com (Aahz)
Date: 18 Jul 2009 16:18:22 -0700
Subject: python command running old version
References: <mailman.3369.1247937914.8015.python-list@python.org>
Message-ID: <h3tl7u$kmf$1@panix3.panix.com>

In article <mailman.3369.1247937914.8015.python-list at python.org>,
Tim Edwards  <timphotoman at gmail.com> wrote:
>
>I upgraded python this morning and entering python from the command
>line runs the old version.
>
>Just looked and it appears the old version is in /usr/bin while the
>new one is in /usr/local/bin/
>
>Besides changing the path order, how do I ensure it runs the new
>version? I'm sure I'll bang my head on the desk in shame as soon as
>I'm reminded.

You probably want to create an alias for command-line usage; scripts
should use the full path to the interpreter you want.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From sjmachin at lexicon.net  Sat Jul 18 19:26:21 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sat, 18 Jul 2009 16:26:21 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
Message-ID: <de887523-c9b1-4a5e-b75b-e54bda1d2847@f18g2000prf.googlegroups.com>

On Jul 19, 8:04?am, twgray <twgray2... at gmail.com> wrote:

> send a 4 byte address from the embedded device, how do I convert that,
> in Python, to a 4 byte, or long, number?

struct.unpack() is your friend. Presuming the embedded device is
little-endian, you do:

the_int = struct.unpack('<I', four_bytes)[0]

See http://docs.python.org/library/struct.html


From nobody at nowhere.com  Sat Jul 18 19:52:30 2009
From: nobody at nowhere.com (Nobody)
Date: Sun, 19 Jul 2009 00:52:30 +0100
Subject: How to receive a data file of unknown length using a python
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
Message-ID: <pan.2009.07.18.23.52.30.562000@nowhere.com>

On Sat, 18 Jul 2009 14:33:48 -0700, twgray wrote:

> It appears to be locking up in  'data=self.s.recv(MAXPACKETLEN)' on
> the final packet, which will always be less than MAXPACKETLEN.
> 
> I guess my question is, how do I detect end of data on the client side?

recv() should return zero when the sender closes its end of the connection.

Is the sender actually closing its end? If you are unsure, use a packet
sniffer such as tcpdump to look for a packet with the FIN flag.

If you need to keep the connection open for further transfers, you need to
incorporate some mechanism for identifying the end of the data into the
protocol. As others have suggested, prefixing the data by its length is
one option. Another is to use an end-of-data marker, but then you need a
mechanism to "escape" the marker if it occurs in the data. A length prefix
is probably simpler to implement, but has the disadvantage that you can't
start sending the data until you know how long it is going to be.



From foo at coo.com  Sat Jul 18 19:59:45 2009
From: foo at coo.com (Dave)
Date: Sun, 19 Jul 2009 00:59:45 +0100
Subject: Newbie question - running a command and looking at output
Message-ID: <4a6261ff@212.67.96.135>

I'm trying to run a command (arch -k) and check if the value returned is 
'sun4v' or not.


kirkby at t2:[~] $ arch -k
sun4v

In fact, I want to do 3 three things

1) Check if the system is Solaris.
2) If it is Solaris, check if 'arch -k' prints 'sun4v'
3) If both 1 and 2 are true, copy a file.


Since arch -k is not supported on all systems, the test for Solaris must 
be made first.

I have a test for Solaris (aka SunOS), which copies a file if the 
systems is running Solaris:

import os, shutil

if os.uname()[0] == 'SunOS':
    shutil.copy2('foo.c','bar.c')

How can I change that, so the copy is only performed if 'arch -k' prints 
'sun4v'?



-- 
I respectfully request that this message is not archived by companies as
unscrupulous as 'Experts Exchange' . In case you are unaware,
'Experts Exchange'  take questions posted on the web and try to find
idiots stupid enough to pay for the answers, which were posted freely
by others. They are leeches.


From foo at coo.com  Sat Jul 18 20:08:05 2009
From: foo at coo.com (Dave)
Date: Sun, 19 Jul 2009 01:08:05 +0100
Subject: Newbie question - running a command and looking at output
In-Reply-To: <4a6261ff@212.67.96.135>
References: <4a6261ff@212.67.96.135>
Message-ID: <4a6263f3@212.67.96.135>

Dave wrote:
> I'm trying to run a command (arch -k) and check if the value returned is 
> 'sun4v' or not.
> 
> 
> kirkby at t2:[~] $ arch -k
> sun4v
> 
> In fact, I want to do 3 three things
> 
> 1) Check if the system is Solaris.
> 2) If it is Solaris, check if 'arch -k' prints 'sun4v'
> 3) If both 1 and 2 are true, copy a file.
> 
> 
> Since arch -k is not supported on all systems, the test for Solaris must 
> be made first.
> 
> I have a test for Solaris (aka SunOS), which copies a file if the 
> systems is running Solaris:
> 
> import os, shutil
> 
> if os.uname()[0] == 'SunOS':
>    shutil.copy2('foo.c','bar.c')
> 
> How can I change that, so the copy is only performed if 'arch -k' prints 
> 'sun4v'?
> 
> 
> 

Actually, when I look at oluname, it does print sunnv:


 >>> import os
 >>> os.uname()
('SunOS', 't2', '5.10', 'Generic_141414-02', 'sun4v')


I guess all I need to do is check for the value of os.uname()[4] too.


-- 
I respectfully request that this message is not archived by companies as
unscrupulous as 'Experts Exchange' . In case you are unaware,
'Experts Exchange'  take questions posted on the web and try to find
idiots stupid enough to pay for the answers, which were posted freely
by others. They are leeches.


From sjmachin at lexicon.net  Sat Jul 18 20:12:32 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sat, 18 Jul 2009 17:12:32 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
Message-ID: <3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>

On Jul 19, 7:43?am, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
> twgray wrote:
> > I am attempting to send a jpeg image file created on an embedded
> > device over a wifi socket to a Python client running on a Linux pc
> > (Ubuntu). ?All works well, except I don't know, on the pc client side,
> > what the file size is? ?
>
> You don't. Sockets are just endless streams of bytes. You will have to design some form
> of 'wire protocol' that includes the length of the message that is to be read.

Apologies in advance for my ignorance -- the last time I dipped my toe
in that kind of water, protocols like zmodem and Kermit were all the
rage -- but I would have thought there would have been an off-the-
shelf library for peer-to-peer file transfer over a socket
interface ... not so?


From python at mrabarnett.plus.com  Sat Jul 18 20:33:32 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 01:33:32 +0100
Subject: How to receive a data file of unknown length using a
	python	socket?
In-Reply-To: <pan.2009.07.18.23.52.30.562000@nowhere.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<pan.2009.07.18.23.52.30.562000@nowhere.com>
Message-ID: <4A6269DC.1010409@mrabarnett.plus.com>

Nobody wrote:
> On Sat, 18 Jul 2009 14:33:48 -0700, twgray wrote:
> 
>> It appears to be locking up in  'data=self.s.recv(MAXPACKETLEN)' on
>> the final packet, which will always be less than MAXPACKETLEN.
>>
>> I guess my question is, how do I detect end of data on the client side?
> 
> recv() should return zero when the sender closes its end of the connection.
> 
> Is the sender actually closing its end? If you are unsure, use a packet
> sniffer such as tcpdump to look for a packet with the FIN flag.
> 
> If you need to keep the connection open for further transfers, you need to
> incorporate some mechanism for identifying the end of the data into the
> protocol. As others have suggested, prefixing the data by its length is
> one option. Another is to use an end-of-data marker, but then you need a
> mechanism to "escape" the marker if it occurs in the data. A length prefix
> is probably simpler to implement, but has the disadvantage that you can't
> start sending the data until you know how long it is going to be.
> 
You could send it in chunks, ending with a chunk length of zero.


From twgray2007 at gmail.com  Sat Jul 18 22:02:05 2009
From: twgray2007 at gmail.com (twgray)
Date: Sat, 18 Jul 2009 19:02:05 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<pan.2009.07.18.23.52.30.562000@nowhere.com>
	<mailman.3385.1247963593.8015.python-list@python.org>
Message-ID: <2b0e3c3c-2beb-46c3-acf6-86aee8caa2ed@b15g2000yqd.googlegroups.com>

On Jul 18, 7:33?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Nobody wrote:
> > On Sat, 18 Jul 2009 14:33:48 -0700, twgray wrote:
>
> >> It appears to be locking up in ?'data=self.s.recv(MAXPACKETLEN)' on
> >> the final packet, which will always be less than MAXPACKETLEN.
>
> >> I guess my question is, how do I detect end of data on the client side?
>
> > recv() should return zero when the sender closes its end of the connection.
>
> > Is the sender actually closing its end? If you are unsure, use a packet
> > sniffer such as tcpdump to look for a packet with the FIN flag.
>
> > If you need to keep the connection open for further transfers, you need to
> > incorporate some mechanism for identifying the end of the data into the
> > protocol. As others have suggested, prefixing the data by its length is
> > one option. Another is to use an end-of-data marker, but then you need a
> > mechanism to "escape" the marker if it occurs in the data. A length prefix
> > is probably simpler to implement, but has the disadvantage that you can't
> > start sending the data until you know how long it is going to be.
>
> You could send it in chunks, ending with a chunk length of zero.

Thanks for the help!


From aahz at pythoncraft.com  Sat Jul 18 22:46:01 2009
From: aahz at pythoncraft.com (Aahz)
Date: 18 Jul 2009 19:46:01 -0700
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
	<mailman.3382.1247958334.8015.python-list@python.org>
Message-ID: <h3u1d9$9m7$1@panix3.panix.com>

In article <mailman.3382.1247958334.8015.python-list at python.org>,
MRAB  <python at mrabarnett.plus.com> wrote:
>
>If you send the length as 4 bytes then you'll have to decide whether
>it's big-endian or little-endian. An alternative is to send the length
>as characters, terminated by, say, '\n' or chr(0).

Alternatively, make it a fixed-length string of bytes, zero-padded in
front.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From piet at cs.uu.nl  Sun Jul 19 02:55:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 08:55:20 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
Message-ID: <m2k525qi07.fsf@cs.uu.nl>

>>>>> John Machin <sjmachin at lexicon.net> (JM) wrote:

>JM> On Jul 19, 7:43?am, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
>>> twgray wrote:
>>> > I am attempting to send a jpeg image file created on an embedded
>>> > device over a wifi socket to a Python client running on a Linux pc
>>> > (Ubuntu). ?All works well, except I don't know, on the pc client side,
>>> > what the file size is? ?
>>> 
>>> You don't. Sockets are just endless streams of bytes. You will have to design some form
>>> of 'wire protocol' that includes the length of the message that is to be read.

>JM> Apologies in advance for my ignorance -- the last time I dipped my toe
>JM> in that kind of water, protocols like zmodem and Kermit were all the
>JM> rage -- but I would have thought there would have been an off-the-
>JM> shelf library for peer-to-peer file transfer over a socket
>JM> interface ... not so?

Yes, many of them, for example HTTP or FTP. But I suppose they are
overkill in this situation. There are also remote procedure call
protocols which can do much more, like XMLRPC.

By the way if the image file
is the only thing you send, the client should close the socket after
sending and then the receiver will detect end of file which will be
detected by your `if len(data) == 0:'
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jeremy.cowles at gmail.com  Sun Jul 19 03:12:47 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Sun, 19 Jul 2009 00:12:47 -0700
Subject: Import hashlib fails, embedded
Message-ID: <373cf0740907190012q74da1d22le6b1bd03930acd78@mail.gmail.com>

I'm working on an embeddded Python interpreter (using the c-api) where we
are loading a custom, zipped copy of the standard Python library
(./lib/python25.zip).

Everything is working fine, but when I try to "import hashlib", i get the
following error:

Traceback (most recent call last):
  File "tryrun.py", line 2, in <module>
    import hashlib
  File "~/workspace/pyboinc/lib/python25.zip/hashlib.py", line 133, in
<module>
  File "~/workspace/pyboinc/lib/python25.zip/hashlib.py", line 60, in
__get_builtin_constructor
ImportError: No module named _md5

I assume this is related to a builtin or dynamically loaded C module, but
I'm not sure exactly what the problem is. Can anyone explain to me what is
going wrong? Other modules (like sys, os) are working fine, which may be
because they are pure-Python modules.

Here is the main function:

int main(int argc, const char* argv[])
{
    if (argc < 2) {
        cerr << "Module name missing\n";
        cerr << "usage: " << argv[0] << " module" << endl;
        return 1;
    }

    // get the python library name
    char* libname = get_lib_name();

    // try to copy the library from ./libname to ./lib/libname
    if (!copy_lib(libname)) {
        return 1;
    }

    Py_SetProgramName((char*)argv[0]);
    Py_SetPythonHome("./");
    Py_Initialize();

    if (argc > 0){
        PySys_SetArgv(argc-1, (char**)(argv+1));
    }

    {
        PyObject* syspath = PySys_GetObject("path");
        if (!syspath) {
            cerr << "Couldn't get sys.path" << endl;
            return 1;
        }
        if (!PyList_Check(syspath)) {
            cerr << "sys.path not a list" << endl;
            return 1;
        }
        PyObject* str = PyString_FromString(".");
        PyList_Append(syspath, str);
        Py_DECREF(str);
    }

    Py_InitModule("boinc", BoincMethods);

    PyObject* name = PyString_FromString(argv[1]);

    PyObject* mod = PyImport_Import(name);
    Py_DECREF(name);

    if (!mod) {
        cerr << "Error loading module" << endl;
        PyErr_Print();
        return 1;
    }
    Py_DECREF(mod);

    Py_Finalize();
}

--
Jeremy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/4cf2eb70/attachment.html>

From __peter__ at web.de  Sun Jul 19 03:21:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Sun, 19 Jul 2009 09:21:15 +0200
Subject: how two join and arrange two files together
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
	<h3s3uu$8pk$00$1@news.t-online.com>
	<mailman.3352.1247909380.8015.python-list@python.org>
Message-ID: <h3uhgp$lr9$01$1@news.t-online.com>

amrita at iisermohali.ac.in wrote:

[please keep the correspondence on the mailing list/newsgroup]

> It is working sir, but my datas are on file when i replaced StringIO("")
> with open("filename.txt") then it is not printing the result properly,
> like in one file i have data like:---
> 33 ALA H = 7.57 N = 121.52 CA = 55.58 HA = 3.89 C = 179.24
> 38 ALA H = 8.29 N = 120.62 CA = 54.33 HA = 4.04 C = 178.95
> 8 ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98  C = 179.39
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
> 21 ALA H = 7.66 N = 123.58 CA = 54.33 HA = 4.05 C = 179.35
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93
> in other:---
> 8 ALA  helix (helix_alpha, helix1)
> 21 ALA  helix (helix_alpha, helix2)
> 23 ALA  helix (helix_alpha, helix2)
> 33 ALA  helix (helix_alpha, helix3)
> 38 ALA  helix (helix_alpha, helix3)
> 49 ALA  bend
> and it is giving the result:-
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18|
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93|23 ALA  helix
> (helix_alpha, helix2)
> 38 ALA H = 8.29 N = 120.62 CA = 54.33 HA = 4.04 C = 178.95|38 ALA  helix
> (helix_alpha, helix3)
>           |49 ALA  bend
> 8 ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98  C = 179.39|8 ALA  helix
> (helix_alpha, helix1)
> it is not printing the result for 33 and 21.

Hint: you have to adapt the key() function from

    def key(line):
        return line[:1]

to something that returns the same key for lines in the two files that 
belong together, and different keys for lines that don't.

Peter



From vs at it.uu.se  Sun Jul 19 04:04:10 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Sun, 19 Jul 2009 10:04:10 +0200
Subject: On out-of-date Python Applications
Message-ID: <4A62D37A.5080105@it.uu.se>

I am not a heavy user of Python; but, I do work with it and some of its 
application packages (e.g. PyODE), in an academic setting.
Many of these applications packages have a Windows installer which 
usually works fine. However, I also try to keep up with the latest 
release of Python, and this is where I often have problems. That is, the 
latest Windows installer provided for some of these applications will 
not install on the latest version of Python.

I do understand that there can be a time lag between the release of 
Python applications and the latest Python. I also appreciate the work of 
the people that are responsible for these applications.

My question is --- Is there anything I, as a user of an application 
package that is out-of-date with respect to the latest Python, can do to 
help in this process of bringing an application  up-to-date?

--V. Stokes



From motoom at xs4all.nl  Sun Jul 19 04:38:46 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Sun, 19 Jul 2009 10:38:46 +0200
Subject: On out-of-date Python Applications
In-Reply-To: <4A62D37A.5080105@it.uu.se>
References: <4A62D37A.5080105@it.uu.se>
Message-ID: <4A62DB96.8000302@xs4all.nl>

Virgil Stokes wrote:

 > some of these applications will
> not install on the latest version of Python.

Which version of Python precisely?



-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From mail at microcorp.co.za  Sun Jul 19 05:47:07 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 19 Jul 2009 11:47:07 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
Message-ID: <200907191147.07949.mail@microcorp.co.za>

On Sunday 19 July 2009 02:12:32 John Machin wrote:
>
> Apologies in advance for my ignorance -- the last time I dipped my toe
> in that kind of water, protocols like zmodem and Kermit were all the
> rage -- but I would have thought there would have been an off-the-
> shelf library for peer-to-peer file transfer over a socket
> interface ... not so?

*Grins at the references to Kermit and zmodem, 
and remembers Laplink and PC Anywhere*

If there is such a transfer beast in Python, I have 
not found it.
(There is an FTP module but that is not quite
the same thing)

I think it is because the network stuff is
all done in the OS or NFS and SAMBA 
now - with drag and drop support and 
other nice goodies.

I have ended up writing a netstring thingy,
that addresses the string transfer problem
by having a start sentinel, a four byte ASCII
length (so you can see it with a packet 
sniffer/displayer) and the rest of the
data escaped to take out the start
sentinel and the escape character.

It works, but the four byte ASCII limits the size
of what can be sent and received.

It guarantees to deliver either the whole
string, or fail, or timeout.

If anybody is interested I will attach the 
code here. It is not a big module.

This question seems to come up periodically
in different guises.

To the OP:

There are really very few valid ways of
solving the string transfer problem,
given a featureless stream of bytes
like a socket.

The first thing that must be addressed
is to sync up - you have to somehow
find the start of the thing as it comes 
past.

And the second is to find the end of the 
slug of data that you are transferring.

So the simplest way is to designate a byte 
as a start and end sentinel, and to make 
sure that such a byte does not occur in 
the data stream, other than as a start
and end marker.  This process is called
escaping, and the reverse is called
unescaping. (SDLC/HDLC does this at a bit 
pattern level)

Another way is to use time, namely to
rely on there being some minimum
time between slugs of data.  This 
does not work well on TCP/IP sockets,
as retries at the lower protocol levels
can give you false breaks in the stream.
It works well on direct connections like
RS-232 or RS-485/422 lines.

Classic netstrings send length, then data.
They rely on the lower level protocols and
the length sent for demarcation of
the slug, and work well if you connect,
send a slug or two, and disconnect.  They 
are not so hot for long running processes, 
where processors can drop out while
sending - there is no reliable way for a 
stable receiver to sync up again if it is
waiting for a slug that will not finish.

Adapting the netstring by adding a sync
character and time out is a compromise 
that I have found works well in practice.

- Hendrik



From sjmachin at lexicon.net  Sun Jul 19 06:17:49 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 19 Jul 2009 03:17:49 -0700 (PDT)
Subject: On out-of-date Python Applications
References: <mailman.3387.1247990649.8015.python-list@python.org>
Message-ID: <63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>

On Jul 19, 6:04?pm, Virgil Stokes <v... at it.uu.se> wrote:
> I am not a heavy user of Python; but, I do work with it and some of its
> application packages (e.g. PyODE), in an academic setting.
> Many of these applications packages have a Windows installer which
> usually works fine. However, I also try to keep up with the latest
> release of Python, and this is where I often have problems. That is, the
> latest Windows installer provided for some of these applications will
> not install on the latest version of Python.

If the package was written for 2.x and "the latest version of Python"
means 3.X, this is not surprising; your options are (1) wait until the
package maintainer releases a 3.x-compatible version (2) port it to
3.x yourself (3) use 2.6

Otherwise: What does "will not install" mean? Are these pure Python
packages or do they include C extensions (binary (pyd) or source?)? At
what stage of the installation does the installation fail? With what
error message(s)? With what versions of Python?



>
> I do understand that there can be a time lag between the release of
> Python applications and the latest Python. I also appreciate the work of
> the people that are responsible for these applications.
>
> My question is --- Is there anything I, as a user of an application
> package that is out-of-date with respect to the latest Python, can do to
> help in this process of bringing an application ?up-to-date?
>
> --V. Stokes



From r.grimm at science-computing.de  Sun Jul 19 07:08:00 2009
From: r.grimm at science-computing.de (Rainer Grimm)
Date: Sun, 19 Jul 2009 04:08:00 -0700 (PDT)
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
Message-ID: <f1bd8096-2956-4c15-acb7-711ee923a06f@c14g2000yqm.googlegroups.com>

Hallo Alan,
> def apply2(itr, methodname, *args, **kwargs):
> ? ? f = operator.methodcaller(methodname, *args, **kwargs)
> ? ? for item in itr:
> ? ? ? ? f(item)
you can do it in a functional way.

>>> class A(object):
...   def hello(self): return "hello: " + str
( self.__class__.__name__ )
...
>>> class B(A):pass
...
>>> class C(A):pass
...
>>> a=A()
>>> b=B()
>>> c=C()
>>> a.hello()
'hello: A'
>>> b.hello()
'hello: B'
>>> c.hello()
'hello: C'
>>>
>>> map( (lambda obj : getattr(obj,"hello")()),(a,b,c))
['hello: A', 'hello: B', 'hello: C']
>>> [ getattr(obj,"hello")() for obj in (a,b,c)]
['hello: A', 'hello: B', 'hello: C']

Greetings from Rottenburg,
Rainer


From hubaghdadi at gmail.com  Sun Jul 19 07:22:57 2009
From: hubaghdadi at gmail.com (Hussein B)
Date: Sun, 19 Jul 2009 04:22:57 -0700 (PDT)
Subject: A little help with pexpect
Message-ID: <d5f4fbbf-82fb-453c-a4d6-f4708f0bd46e@m11g2000yqh.googlegroups.com>

Hey,
I'm trying to execute a command over a remore server using pexpect
+++++++++++++++++
url = 'ssh internalserver'
res = pexpect.spawn(url)
print '1'
res.expect('.*ssword:')
print '2'
res.sendline('mypasswd')
print '3'
res.sendline('ls -aslh')
+++++++++++++++++
What I want to do is to send a couple of commands and get the
response.
How to do this?
Thanks.


From python at bdurham.com  Sun Jul 19 09:18:21 2009
From: python at bdurham.com (python at bdurham.com)
Date: Sun, 19 Jul 2009 09:18:21 -0400
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <200907191147.07949.mail@microcorp.co.za>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
	<200907191147.07949.mail@microcorp.co.za>
Message-ID: <1248009501.29158.1325749595@webmail.messagingengine.com>

Hi Hendrik,

> I have ended up writing a netstring thingy, that addresses the string transfer problem by having a start sentinel, a four byte ASCII length (so you can see it with a packet sniffer/displayer) and the rest of the data escaped to take out the start sentinel and the escape character. It works, but the four byte ASCII limits the size of what can be sent and received. It guarantees to deliver either the whole string, or fail, or timeout.

> If anybody is interested I will attach the code here. It is not a big module.

I am interested in seeing your code and would be grateful if you shared
it with this list.

Thank you,
Malcolm


From piet at cs.uu.nl  Sun Jul 19 09:24:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 15:24:26 +0200
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<f1bd8096-2956-4c15-acb7-711ee923a06f@c14g2000yqm.googlegroups.com>
Message-ID: <m21vocrek5.fsf@cs.uu.nl>

>>>>> Rainer Grimm <r.grimm at science-computing.de> (RG) a ?crit:

>RG> Hallo Alan,
>>> def apply2(itr, methodname, *args, **kwargs):
>>> ? ? f = operator.methodcaller(methodname, *args, **kwargs)
>>> ? ? for item in itr:
>>> ? ? ? ? f(item)
>RG> you can do it in a functional way.

>>>>> class A(object):
>RG> ...   def hello(self): return "hello: " + str
>RG> ( self.__class__.__name__ )
>RG> ...
>>>>> class B(A):pass
>RG> ...
>>>>> class C(A):pass
>RG> ...
>>>>> a=A()
>>>>> b=B()
>>>>> c=C()
>>>>> a.hello()
>RG> 'hello: A'
>>>>> b.hello()
>RG> 'hello: B'
>>>>> c.hello()
>RG> 'hello: C'
>>>>> 
>>>>> map( (lambda obj : getattr(obj,"hello")()),(a,b,c))
>RG> ['hello: A', 'hello: B', 'hello: C']
>>>>> [ getattr(obj,"hello")() for obj in (a,b,c)]
>RG> ['hello: A', 'hello: B', 'hello: C']

But that creates an unnecessary list.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From victorsubervi at gmail.com  Sun Jul 19 09:24:43 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 19 Jul 2009 15:24:43 +0200
Subject: Auto Send URL
In-Reply-To: <50697b2c0907181032x6f0029dfs304a345ca2835690@mail.gmail.com>
References: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>
	<50697b2c0907181032x6f0029dfs304a345ca2835690@mail.gmail.com>
Message-ID: <4dc0cfea0907190624g691688cdlef20acd77b88746b@mail.gmail.com>

Ah. How easy! Thank you.

On Sat, Jul 18, 2009 at 7:32 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Fri, Jul 17, 2009 at 6:02 AM, Victor Subervi<victorsubervi at gmail.com>
> wrote:
> > Hi;
> > I am trying to script code that automatically sends a Web site visitor to
> an
> > URL. Specifically, when they enter a value in a search box, I have that
> form
> > sent to a script that writes an URL acceptable to Google, then I want to
> > send the visitor off without him having to click another button. How do I
> do
> > this?
>
> Send back a webpage with a Refresh meta tag:
>
> <html>
>    <head>
>    <meta http-equiv="Refresh" content="0; url=http://YOUR-URL-HERE/">
>    </head>
> </html>
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/f25e90e4/attachment.html>

From alan.isaac at gmail.com  Sun Jul 19 09:48:16 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sun, 19 Jul 2009 13:48:16 GMT
Subject: are user defined classes hashable?
Message-ID: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>

Are user defined classes hashable?
(The classes; *not* the instances!)

I want to use some classes as dictionary keys.
Python is not objecting,
but I'm not sure how to think about
whether this could be dangerous.
I'm inclined to guess it will be hashed by id
and this is OK.

Thanks for any insights,
Alan Isaac


From Nicolas.Dandrimont at crans.org  Sun Jul 19 10:07:57 2009
From: Nicolas.Dandrimont at crans.org (Nicolas Dandrimont)
Date: Sun, 19 Jul 2009 10:07:57 -0400
Subject: are user defined classes hashable?
In-Reply-To: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
Message-ID: <20090719140757.GB11029@dirichlet.crans.org>

* Alan G Isaac <alan.isaac at gmail.com> [2009-07-19 13:48:16 +0000]:

> Are user defined classes hashable?
> (The classes; *not* the instances!)
> 
> I want to use some classes as dictionary keys.
> Python is not objecting,
> but I'm not sure how to think about
> whether this could be dangerous.
> I'm inclined to guess it will be hashed by id
> and this is OK.

You can check for yourself:

In [1]: class Foo(object):
   ...:     pass
   ...: 

In [2]: foo = Foo()

In [3]: hash
hash

In [3]: hash(foo)
Out[3]: 15294992

In [4]: id(foo)
Out[4]: 15294992

So yes, by default, user-defined classes are hashable, by id. You can
override this behaviour by defining the __hash__ special method on
your object.

HTH,
-- 
Nicolas Dandrimont
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/ca0c9da8/attachment.sig>

From mark.dufour at gmail.com  Sun Jul 19 10:30:57 2009
From: mark.dufour at gmail.com (Mark Dufour)
Date: Sun, 19 Jul 2009 16:30:57 +0200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
Message-ID: <8180ef690907190730t50ccc2f4sb7f489e7c9bb9fb8@mail.gmail.com>

Hi all,

I have just released version 0.2 of Shed Skin, an experimental
(restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).
It comes with 7 new example programs (for a total of 40 example
programs, at over 12,000 lines) and several important improvements/bug
fixes. See http://code.google.com/p/shedskin/wiki/ReleaseNotes for the
full changelog.

The new example programs consist of Disco, an elegant go player (see
http://shed-skin.blogspot.com/2009/07/disco-elegant-python-go-player.html),
a larger Voronoi implementation at 800 lines, a TSP algorithm
simulating ant colonies, a nicer neural network algorithm and three
compressors (Lempel-Ziv, huffman block, and arithmetic).

Other than bug fixes for these programs, this release adds some
important optimizations. First and foremost, inlining was greatly
improved, resulting in potential speedups across the board. Second,
loops such as 'for a, b in enumerate/zip(sequence[, sequence])' should
now be dramatically faster (also inside list comprehensions), by
avoiding allocation of intermediate tuples. Finally, basic list
slicing should now be much faster.
 	

Please try it out!
Mark Dufour.
-- 
"One of my most productive days was throwing away 1000 lines of code"
- Ken Thompson


From alan.isaac at gmail.com  Sun Jul 19 10:46:12 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sun, 19 Jul 2009 14:46:12 GMT
Subject: are user defined classes hashable?
In-Reply-To: <mailman.3392.1248012803.8015.python-list@python.org>
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<mailman.3392.1248012803.8015.python-list@python.org>
Message-ID: <UkG8m.277$MA3.146@nwrddc02.gnilink.net>

> * Alan G Isaac <alan.isaac at gmail.com> [2009-07-19 13:48:16  +0000]:
>> Are user defined classes hashable? 
>> (The classes; *not* the instances!)
>> I'm inclined to guess it will be hashed by id and this is 
>> OK. 


On 7/19/2009 10:07 AM Nicolas Dandrimont apparently wrote:
> You can check for yourself:

> In [1]: class Foo(object):
>    ...:     pass
>    ...:

> In [2]: foo = Foo()

> In [3]: hash(foo)
> Out[3]: 15294992 

> In [4]: id(foo)
> Out[4]: 15294992 



Again, my question is about the class not its instances,
but still, checking as you suggest gives the same answer.

Thanks,
Alan


From piet at cs.uu.nl  Sun Jul 19 10:49:09 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 16:49:09 +0200
Subject: A little help with pexpect
References: <d5f4fbbf-82fb-453c-a4d6-f4708f0bd46e@m11g2000yqh.googlegroups.com>
Message-ID: <m2ws64pw2i.fsf@cs.uu.nl>

>>>>> Hussein B <hubaghdadi at gmail.com> (HB) wrote:

>HB> Hey,
>HB> I'm trying to execute a command over a remore server using pexpect
>HB> +++++++++++++++++
>HB> url = 'ssh internalserver'
>HB> res = pexpect.spawn(url)
>HB> print '1'
>HB> res.expect('.*ssword:')
>HB> print '2'
>HB> res.sendline('mypasswd')
>HB> print '3'
>HB> res.sendline('ls -aslh')
>HB> +++++++++++++++++
>HB> What I want to do is to send a couple of commands and get the
>HB> response.
>HB> How to do this?
>HB> Thanks.

You can read the output with res.readline() in a loop or similar. The
problem is when to stop. You could look in the returned string for the
prompt and hope the prompt doesn't accidentally occur in the output.

You can also do res.expect(prompt) and get res.before() Same problem
with accidentally occurrence of the prompt.

Another way is to use a timeout, e.g. with read_nonblocking or
specifying a timeout at the spawn call.

You can also consider using paramiko instead of pexpect. It gives you
considerably more control. For each command you van open a `channel' and
that acts more or less similar to a socket, i.e. you get a decent EOF at
the end of the command's output. This implies that you have to create a
new channel for each command, but it stays within the same SSH
connection (SSH allows subconnections).

Example:

>>> import paramiko
...Mumbles about deprecated modules...
>>> hostname='server.example.net'
>>> port = 22
>>> t = paramiko.Transport((hostname, port))
>>> username = 'user'
>>> password = '********'
>>> t.connect(username=username, password=password)

Open a channel for a command

>>> chan = t.open_session()
>>> chan.exec_command('ls -l')
>>> chan.recv(999999)
'total 0\ndrwxr-xr-x  2 user group 60 Apr  2  2009 Mail\ndrwx------  2 user group  6 Dec 27  2008 tmp\n'
>>> chan.recv(999999)
''

That was end of file.
Open a new channel for a new command

>>> chan = t.open_session()
>>> chan.exec_command('cat')
>>> chan.send('abcdefghijklmn\n')
15
>>> chan.recv(99)
'abcdefghijklmn\n'
>>> 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From resurtm at gmail.com  Sun Jul 19 11:03:21 2009
From: resurtm at gmail.com (resurtm)
Date: Sun, 19 Jul 2009 08:03:21 -0700 (PDT)
Subject: python, ctypes, callbacks -- access violation when calling callback
Message-ID: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>

Hello.

I'm trying to pass to the C function pointer to callback function from
python. But when i'm trying to do this i get access violation within
the DLL file when calling python callback.

Here is the python side code:

from ctypes import *

# ...

class NewtonBody(Structure):
  def __init__(self, pointer = 0):
     self.pointer = pointer

# ...

class Newton:
  def __init__(self):
     self._cdll = CDLL('newton.dll')
     self.world = NewtonWorld()

# ...

  # NewtonBodySetForceAndTorqueCallback
  def bodySetForceAndTorqueCallback(self, body):
     CALLBACK = CFUNCTYPE(c_int, POINTER(NewtonBody), c_float, c_int)
     def callback(a, b, c):
        print '1'
        return 0
     self._cdll.NewtonBodySetForceAndTorqueCallback(body.pointer,
CALLBACK(callback))
     return None

Traceback:

Traceback (most recent call last):
 File "Newton.py", line 119, in <module>
   newton.update(10.5)
 File "Newton.py", line 42, in update
   self._cdll.NewtonUpdate(self.world.pointer, c_float(timestep))
WindowsError: exception: access violation reading 0x3C888899

And finally prototype of function which i'm trying to call and
callback function type declarations:

typedef void (*NewtonApplyForceAndTorque) (const NewtonBody* body,
dFloat timestep, int threadIndex);

// ...

NEWTON_API void  NewtonBodySetForceAndTorqueCallback (const
NewtonBody* body, NewtonApplyForceAndTorque callback);

Can anybody explain my errors when trying to pass callback to DLL
function?

Thanks for advices and solutions!


From lists at cheimes.de  Sun Jul 19 11:09:37 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sun, 19 Jul 2009 17:09:37 +0200
Subject: python, ctypes,
	callbacks -- access violation when calling callback
In-Reply-To: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>
References: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>
Message-ID: <h3vcvg$iku$1@ger.gmane.org>

resurtm wrote:
> Can anybody explain my errors when trying to pass callback to DLL
> function?
> 
> Thanks for advices and solutions!

You have to keep a reference to the callback alive yourself. ctypes
doesn't increase the refernece counter of the function when you define a
callback. As soon as the ref counter reaches 0, the function object is
collected and the pointer to the callback is invalid.

You could assign it to a module global or instance variable.

Christian



From resurtm at gmail.com  Sun Jul 19 11:15:33 2009
From: resurtm at gmail.com (resurtm)
Date: Sun, 19 Jul 2009 08:15:33 -0700 (PDT)
Subject: python, ctypes, callbacks -- access violation when calling 
	callback
References: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>
	<mailman.3394.1248016190.8015.python-list@python.org>
Message-ID: <8df80a1c-ada2-47a8-86ba-a9ed804c57f6@q11g2000yqi.googlegroups.com>

On 19 ???, 21:09, Christian Heimes <li... at cheimes.de> wrote:
> resurtm wrote:
> > Can anybody explain my errors when trying to pass callback to DLL
> > function?
>
> > Thanks for advices and solutions!
>
> You have to keep a reference to the callback alive yourself. ctypes
> doesn't increase the refernece counter of the function when you define a
> callback. As soon as the ref counter reaches 0, the function object is
> collected and the pointer to the callback is invalid.
>
> You could assign it to a module global or instance variable.
>
> Christian

Thanks for help Christian! It's working fine now! ;-)


From forman.simon at gmail.com  Sun Jul 19 11:21:01 2009
From: forman.simon at gmail.com (Calroc)
Date: Sun, 19 Jul 2009 08:21:01 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>

On Jul 9, 1:20 pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
[...]
> You'll excuse my skepticism about all these claims about how anyone can
> program, how easy it is to teach the fundamentals of Turing Machines and
> functional programming to anybody at all. Prove it. Where are your peer-
> reviewed studies demonstrating such successes on randomly chosen people,
> not self-selected motivated, higher-than-average intelligence students?

I'm engaged presently in starting a school to teach programming from
the ground up, based roughly on the curriculum outlined in the article
I mentioned.  I can't randomly select students but I do intend to
gather data about who does how well from what starting conditions.

I'm excited about formal methods because one, I just heard about them,
and two, they provide me with a much more well-fleshed-out way to
bridge rigorously from "raw" Turing machine models to higher order
abstractions.

I'm confident that anyone who can play Sudoku can learn programming
and formal methods.

> In the real world, human beings are prone to serious cognitive biases and
> errors. Our brains are buggy. Take any list of reasoning fallacies, and
> you'll find the majority of people have difficulty avoid them. The first
> struggle is to get them to even accept that they *are* fallacies, but
> even once they have intellectually accepted it, getting them to live up
> to that knowledge in practice is much, much harder.
>
> In fact I'd go further and say that *every single person*, no matter how
> intelligent and well-educated, will fall for cognitive biases and
> fallacious reasoning on a regular basis.

I agree completely.  One of my chief goals is to "debug" human
reasoning to whatever extent possible.  This is precisely where I
expect training in computer programming to come in handy.  The machine
symbol manipulator is not going to be fooled by reasoning fallacies.
Fluency in rigorous symbol manipulation can only help us cope with the
vagaries of our too-often sub-rational wetware.

I think the real win starts when computers can be used as a
communication medium, not for blogs and tweets and SMS txt and IM and
VoIP, but for reasoned symbolically coded discussion.


On Jul 9, 2:10 pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
> >> persistent idea "out there" that programming is a very accessible
> >> skill, like cooking or gardening, anyone can do it, and even profit
> >> from it, monetarily or otherwise, etc., and to some extent I am
>
> > Programming is not like any other human activity.
>
> In practice? In principle? Programming in principle is not the same as it
> is performed in practice.
>
> But in either case, programming requires both the logical reasoning of
> mathematics and the creativity of the arts. Funnily enough,
> mathematicians will tell you that mathematics requires the same, and so
> will the best artists. I think mathematicians, engineers, artists, even
> great chefs, will pour scorn on your claim that programming is not like
> any other human activity.

Well it's actually Dijkstra's claim, and I find it reasonable, that
programming has two novel or unique aspects not present in other areas
of human endeavor: vast scale and digital mechanism.

http://www.cs.utexas.edu/users/EWD/transcriptions/EWD10xx/EWD1036.html


> [...]
>
> > He talks about how "when all is said and done, the only thing computers
> > can do for us is to manipulate symbols and produce results of such
> > manipulations" and he emphasises the "uninterpreted" nature of
> > mechanical symbol manipulation, i.e. that the machine is doing it
> > mindlessly.
>
> "Manipulate symbols" is so abstract as to be pointless. By that

That's the "koan form", longhand he means the Boolean domain {true,
false}, the logical operations and their algebraic relationships, and
the means of using same to deduce new formulae.


> reasoning, I can build a "computer" consisting of a box open at the top.
> I represent a symbol by an object (say, a helium-filled balloon, or a
> stone), instead of a pattern of bits. I manipulate the symbol by holding
> the object over the box and letting go. If it flies up into the sky, that
> represents the symbol "Love is War", if it falls into the box, it
> represents the symbol "Strength is Blue", and if it just floats there, it
> represents "Cheddar Cheese". This is a deterministic, analog computer
> which manipulates symbols. Great.
>
> And utterly, utterly useless. So what is my computer lacking that real
> computers have? When you have answered that question, you'll see why
> Dijkstra's claim is under-specified.

Well, you said it yourself: your computer is lacking utility.


[...]
>
> What is an uninterpreted formula? If you don't interpret it, how can you
> distinguish it from random noise?

Uninterpreted formula means that you manipulate the symbols without
thinking about what they mean.  You just use the rules on the formulae
as such.  To be useful, once you're "done" with them you can consider
their meaning.  You can distinguish it at any time, but Dijktra's
saying that we should pay attention to the [mathematical, logical]
reasoning process as it's own thing, without reference to the meaning
of the symbols, at least temporarily.


[...]
>
> > If you're never exposed to that constellation of concepts that underpins
> > "mechanical symbol manipulation" you are adrift in a sea ("c", ha ha) of
> > abstractions.
>
> > However, if you /are/ exposed to the "so few and simple" rules of
> > manipulation the gates (no pun intended) to the kingdom are thrown wide.
>
> What nonsense. The keys to the kingdom are the abstractions.
>
> Here's an exercise for you, if you dare. It's not that difficult to
> remove the abstraction from integer addition, to explain it in terms of
> bit manipulation. If you prefer, you can write a Turing Machine instead.
>
> Now try doing the same thing for Quicksort. Don't worry, we'll wait.
>
> Once you've done that, let's see you implement a practical, scalable, non-
> toy webserver as a Turing Machine.
>
> No, it's not the fundamental operations that open the doors to the
> kingdom. It's the abstractions. The history of computing is to gain more
> and more power by leveraging better and better abstractions.

I agree that "better and better abstractions" are the key(s), but I
strongly disagree that the fundamental operations are not, uh, key to
those keys.

There are two intertwined phenomenon:

1) formulae, written in symbols

2) deriving new formulae by applying [in]formal methods to existing
formulae

The rules, and the application of those rules, are two separate but
compatible phenomenon. (Compatible in that you can encode the latter
in terms of the former. This is the essential "trick" of mechanized
thought.)

Now (1) is constantly being elaborated, these elaborations are the
"higher" abstractions we're talking about.

But (2) stays the same(-ish) no matter how high you go, and (2) is the
process by which all the higher (1)'s come from, so if we get it right
(and by right I mean of course by using rigorous proofs, formal
methods et. al.) from the get go and keep it right, we're golden.

I do literally intend to teach e.g. "integer addition ... in terms of
bit manipulation" and a bit of parsing too. But I intend to rapidly
bring students to a Forth or Forth-like stage, and then immediately
create simple parsers that implement, for example, C for loops, and
other "higher" abstractions.

Highly abridged, this is the curriculum: Enough about bits to bring
them to bytes, enough bytes to bring them to RAM, enough RAM to
implement a crude CPU, enough CPU to implement a bit of Forth, enough
Forth to implement parsers, and enough parsing (and compilation and
interpreting, etc.) to let them grok languages in general.

Formal methods gives me a wide straight road from each stage to the
next.

[...]
> > Quoting Dijkstra again [1]: "Before we part, I would like to invite you
> > to consider the following way of doing justice to computing's radical
> > novelty in an introductory programming course.
>
> > "On the one hand, we teach what looks like the predicate calculus, but
> > we do it very differently from the philosophers. In order to train the
> > novice programmer in the manipulation of uninterpreted formulae, we
> > teach it more as boolean algebra, familiarizing the student with all
> > algebraic properties of the logical connectives. To further sever the
> > links to intuition, we rename the values {true, false} of the boolean
> > domain as {black, white}.
>
> This is supposed to be a good thing?
>
> Oh my. It must be nice in that ivory tower, never having to deal with
> anyone who hasn't already been winnowed by years of study and self-
> selection before taking on a comp sci course.
>
> I don't think Dijkstra would have taken that suggestion seriously if he
> had to teach school kids instead of college adults.

I'm not going to teach it exactly like he outlines there, but I really
am going to try the curriculum I outlined.  I'll post videos. :]



> ...
>
> > (Did you read that last paragraph and think, "Well how the heck else are
> > you supposed to program a computer if not in a computer language?"?  If
> > so, well, that is kind of my point.)
>
> No. What I thought was, how the hell are you supposed to manipulate
> symbols without a language to describe what sort of manipulations you can
> do?

Direct-manipulation graphical Abstract Syntax Trees.



[...]
> > tables and arrays. He didn't even know that they were different
> > "things".
>
> I shall manfully resist the urge to make sarcastic comments about
> ignorant PHP developers, and instead refer you to my earlier reply to you
> about cognitive biases. For extra points, can you identify all the
> fallacious reasoning in that paragraph of yours?

I'll pass.  I should have resisted the urge to whinge about him in the
first place.



>
> But those abstractions just get in the way, according to you. He should
> be programming in the bare metal, doing pure symbol manipulation without
> language.

No, the abstractions are useful, but their utility is tied to their
reliability, which in turn derives from the formal rigour of the
proofs of the abstractions' correctness.

My issues with modern art are, that too many of these abstractions are
not /proven/, and they are both frozen and fractured by the existing
milieu of "static" mutually incompatible programming languages.

I see a possibility for something better.


> If programming is symbol manipulation, then you should remember that the
> user interface is also symbol manipulation, and it is a MUCH harder
> problem than databases, sorting, searching, and all the other problems
> you learn about in academia. The user interface has to communicate over a
> rich but noisy channel using multiple under-specified protocols to a
> couple of pounds of meat which processes information using buggy
> heuristics evolved over millions of years to find the ripe fruit, avoid
> being eaten, and have sex. If you think getting XML was hard, that's
> *nothing* compared to user interfaces.
>
> The fact that even bad UIs work at all is a credit to the heuristics,
> bugs and all, in the meat.

Ok, yes, but have you read Jef Raskin's "the Humane Interface"?

> > As for "a minimum of bugs"... sigh. The "minimum of bugs" is zero, if
> > you derive your "uninterpreted formulae" /correctly/.

Sorry.  I can't believe that I was so melodramatic.

> And the secret of getting rich on the stock market is to buy low, sell
> high. Very true, and very pointless. How do you derive the formula
> correctly?
>
> Do you have an algorithm to do so? If so, how do you know that algorithm
> is correct?

Well we know logic works, we can trust that. The algorithm of proving
the formula is logic.

> > Deriving provably
> > correct "programs" should be what computer science and computer
> > education are all about
>
> That's impossible. Not just impractical, or hard, or subject to hardware
> failures, but impossible.
>
> I really shouldn't need to raise this to anyone with pretensions of being
> a Computer Scientist and not just a programmer, but... try proving an
> arbitrary program will *halt*.
>
> If you can't do that, then what makes you think you can prove all useful,
> necessary programs are correct?

It may well be that there are useful, necessary programs that are
impossible to prove correct. I'm not trying to claim there aren't
such.

I think that wherever that's not the case, wherever useful necessary
programs can be proven, they should be.

It may be that flawless software is an unreachable asymptote, like the
speed of light for matter, but I'm (recently!) convinced that it's a
goal worthy of exploration and effort.

Just because it's unattainable doesn't make it undesirable.  And who
knows? Maybe the horse will learn to sing.

> > Again with Dijkstra[3]: "The prime paradigma of the pragmatic designer
> > is known as "poor man's induction", i.e. he believes in his design as
> > long as "it works", i.e. until faced with evidence to the contrary. (He
> > will then "fix the design".)
>
> Yes, that is the only way it can be.
>
> > The scientific designer, however, believes
> > in his design because he understands why it will work under all
> > circumstances.
>
> Really? Under *all* circumstances?
>
> Memory failures? Stray cosmic radiation flipping bits? Noise in the power
> supply?
>
> What's that you say? "That's cheating, the software designer can't be
> expected to deal with the actual reality of computers!!! We work in an
> abstract realm where computers never run out of memory, swapping never
> occurs, and the floating point unit is always correct!"

First, yes, that could be considered cheating.  We don't expect
automotive engineers to design for resistance to meteor strikes.
Second, those issues plague all programs, formally derived or not.
Formal methods certainly can't hurt.  Third, in cases where you do
want reliability in the face of things like cosmic rays you're going
to want to use formal methods to achieve it.

And last but not least, it may be possible to "parameterize" the
abstractions we derive with information about their susceptibility to
stability of their underlying abstractions.

> Fail enough. I don't want to make it too hard for you.
>
> Okay, so let's compare the mere "pragmatic designer" with his provisional
> expectation that his code is correct, and Dijkstra's "scientific
> designer". He understands his code is correct. Wonderful!
>
> Er, *how exactly* does he reach that understanding?
>
> He reasons about the logic of the program. Great! I can do that. See,
> here's a proof that binary search is correct. How easy this is.
>
> Now try it for some non-trivial piece of code. Say, the Linux kernel.
> This may take a while...

Well, I'd start with Minix 3...  But really the method would be to
build up provably correct compounds out of proven sub-assemblies.
Even if it takes a long time is it time wasted?  A provably correct OS
is kind of a neat idea IMO.

>
> What guarantee do we have that the scientific designer's reasoning was
> correct? I mean, sure he is convinced he has reasoned correctly, but he
> would, wouldn't he? If he was unsure, he'd keep reasoning (or ask for
> help), until he was sure. But being sure doesn't make him correct. It
> just makes him sure.
>
> So how do you verify the verification?

Peer review and run it through a mechanical verifier.  There is a self-
reflexive loop there but it's not infinite.  If it was we couldn't
implement any computer.

> And speaking of binary search:
[Bentley's binary search bug]

This is a perfect example of leaky abstraction. The C "integer"
doesn't behave like a "real" integer but part of the algorithm's
implementation relied on the tacit overlap between C ints and integers
up to a certain value.  This is the sort of thing that could be
annotated onto the symbolic representation of the algorithm and used
to compile provably correct machine code (for various platforms.)

If the same proven algorithm had been implemented on top of a correct
integer abstraction (like python's long int) it wouldn't have had that
bug.

(And yes, there would still be limits, truly vast arrays could
conceivably result in memory exhaustion during execution of the sort.
I think the answer there lies in being able to represent or calculate
the limits of an algorithm explicitly, the better to use it correctly
in other code.)

> Perhaps the "scientific designer" should be a little less arrogant, and
> take note of the lesson of real science: all knowledge is provisional and
> subject to correction and falsification.

(I apologize for my arrogance on behalf of formal methods, I just
found out about them and I'm all giddy and irritating.)

> Which really makes the "scientific designer" just a slightly more clever
> and effective "pragmatic designer", doesn't it?

Um, er, well, scientists are ultimate pragmatists, and Dijkstra's
description of "pragmatic designer" above could well be applied to
"scientific designers".  The difference turns on /why/ each person has
confidence is his design: one can prove mathematically that his design
is correct while the other is ... sure.

Whether or not the delivered software is actually flawless, the
difference seems to me more than just "slightly more clever and
effective".

>
> > The transition from pragmatic to scientific design would
> > indeed be a drastic change within the computer industry."
>
> Given Dijkstra's definition of "scientific design", it certainly would.
> It would be as drastic a change as the discovery of Immovable Objects and
> Irresistible Forces would be to engineering, or the invention of a
> Universal Solvent for chemistry, or any other impossibility.
>
> > "Obviously no errors" is the goal to strive for, and I am comfortable
> > calling anyone an amateur who prefers "no obvious errors."
>
> It's not a matter of preferring no obvious errors, as understanding the
> limitations of reality. You simply can't do better than no obvious errors
> (although of course you can do worse) -- the only question is what you
> call "obvious".

It may be expensive, it may be difficult, and it may certainly be
impossible, but I feel the shift from ad hoc software creation to
rigorous scientific software production is obvious.  To me it's like
the shift from astrology to astronomy, or from alchemy to chemistry.


~Simon


From victorsubervi at gmail.com  Sun Jul 19 11:35:58 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 19 Jul 2009 17:35:58 +0200
Subject: Getting a Form To Work
Message-ID: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>

Hi;
I have the following in a *.py page for the Web:

from primeNumbers import primeNumbers

try:
  num = form.getfirst('num')
except:
  num = ''
  msg = "Oops"

print "Content-Type: text/html"
print
print """
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<head xmlns="http://www.w3.org/1999/xhtml">
</head>
"""
if num != '':
  try:
    num = round(float(num))
    roots = primeNumbers(num)
    print roots
  except:
    msg += "We're sorry! You entered something that is not a number. Please
try again.<br />\n"
    num = ''
if num == '':
  print msg
  print "Num:", num
  print """
<form action="http://13gems.com/test-Calculators_frame.py" method="post">
<input type="text" name="num" size="20" maxlength="20" value="Enter number
here..." onfocus="this.value=''" />
<input type="image" src="http://13gems.com/images/search.jpg" name="search"
id="search" />
</form>
"""
print '</body></html>\n'

Now, "Oops" never gets printed, nor does the variable num (although a blank
space appears to print). I am calling the very page to which the form sends
its values. Assuming the imported module works, why don?t I get anything
printed?
TIA,
Victor
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/7d952367/attachment.html>

From Nicolas.Dandrimont at crans.org  Sun Jul 19 11:39:31 2009
From: Nicolas.Dandrimont at crans.org (Nicolas Dandrimont)
Date: Sun, 19 Jul 2009 11:39:31 -0400
Subject: are user defined classes hashable?
In-Reply-To: <UkG8m.277$MA3.146@nwrddc02.gnilink.net>
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<mailman.3392.1248012803.8015.python-list@python.org>
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net>
Message-ID: <20090719153931.GA14960@dirichlet.crans.org>

* Alan G Isaac <alan.isaac at gmail.com> [2009-07-19 14:46:12 +0000]:
 
> Again, my question is about the class not its instances,
> but still, checking as you suggest gives the same answer.

That's what I get for answering before my coffee!

Cheers,
-- 
Nicolas Dandrimont

"Linux poses a real challenge for those with a taste for late-night
hacking (and/or conversations with God)."
(By Matt Welsh)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/1ed5e04d/attachment.sig>

From sajmikins at gmail.com  Sun Jul 19 11:45:20 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sun, 19 Jul 2009 08:45:20 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<mailman.3088.1247577307.8015.python-list@python.org> 
	<Xns9C48B8D5619D0duncanbooth@127.0.0.1>
Message-ID: <d65f4dac-2aad-46cf-a997-9a6cbdaf165d@w41g2000yqb.googlegroups.com>

On Jul 14, 1:10?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> John Machin <sjmac... at lexicon.net> wrote:
> > Try an iterative version of checking that () [] and {}
> > are balanced and nested appropriately.
>
> Here's how I might approach the more general case:
>
> def balanced(s, parens=("()",)):
> ? ? '''
> ? ? Example:
> ? ? >>> balanced('aAAA(b[bb(c]c))')
> ? ? True
> ? ? >>> balanced('aAAA(b[bb(c]c))', parens=("()", "[]"))
> ? ? False
> ? ? '''
> ? ? s = re.sub("[^%s]+" % re.escape("".join(parens)), "", s)
> ? ? for i in range(len(s)/2):
> ? ? ? ? for p in parens:
> ? ? ? ? ? ? s = s.replace(p, "")
> ? ? return not s
>
> For short strings this is obviously slower than your 'iterative' function,
> but the run time mostly depends on the number of pairs of parentheses
> rather than the total length of the string, so for example it starts
> winning on a string with 2 pairs of parentheses about 75 characters long.


def balanced(s, pairs=('()', '[]', '{}')):
    opening = {}
    closing = {}
    for open_, close in pairs:
        opening[open_] = closing[close] = object()

    stack = []

    for char in s:

        marker = opening.get(char)
        if marker:
            stack.append(marker)
            continue

        marker = closing.get(char)
        if marker:
            try:
                if stack.pop() is not marker:
                    return False
            except IndexError:
                return False

    # All markers should be popped.
    return not stack


Can parse sequences other than strings. :]


From sjmachin at lexicon.net  Sun Jul 19 11:47:17 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 01:47:17 +1000
Subject: On out-of-date Python Applications
In-Reply-To: <4A632C9D.2010303@it.uu.se>
References: <mailman.3387.1247990649.8015.python-list@python.org>
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>
	<4A632C9D.2010303@it.uu.se>
Message-ID: <4A634005.6080505@lexicon.net>

On 20/07/2009 12:24 AM, Virgil Stokes wrote:
> John Machin wrote:
>> On Jul 19, 6:04 pm, Virgil Stokes <v... at it.uu.se> wrote:
>>   
>>> I am not a heavy user of Python; but, I do work with it and some of its
>>> application packages (e.g. PyODE), in an academic setting.
>>> Many of these applications packages have a Windows installer which
>>> usually works fine. However, I also try to keep up with the latest
>>> release of Python, and this is where I often have problems. That is, the
>>> latest Windows installer provided for some of these applications will
>>> not install on the latest version of Python.
>>>     
>>
>> If the package was written for 2.x and "the latest version of Python"
>> means 3.X, this is not surprising; your options are (1) wait until the
>> package maintainer releases a 3.x-compatible version (2) port it to
>> 3.x yourself (3) use 2.6
>>   
> Actually John,
> My question was about the more general case --- how to help with 
> upgrading applications; but, I will try to address your email.
>> Otherwise: What does "will not install" mean? 
> This means that when the Windows installer is executed it informs you 
> that you do not have a match between the application and the Python that 
> it finds on your Windows PC. You can easily find this out for yourself 
> by trying to install PyODE on a Windows platform with a Python version 
> later than 2.5.x.
>> Are these pure Python
>> packages or do they include C extensions (binary (pyd) or source?)? 
> Obviously, this depends on the application. In the particular case that 
> I mentioned (PyODE) I believe that there is a mix of C binaries and 
> Python code.
>> At
>> what stage of the installation does the installation fail? 
> In the initial stages.
>> With what
>> error message(s)? 
> In one specific case, the message is (paraphrasing) "You do not have 
> Python 2.5 installed" --- the installation is then aborted.
>> With what versions of Python?
>>   
> I have only Python 2.6.2 on my home Windows Vista PC and PyODE does not 
> have a Windows Installer for Python 2.6.
>>
>>
>>   
>>> I do understand that there can be a time lag between the release of
>>> Python applications and the latest Python. I also appreciate the work of
>>> the people that are responsible for these applications.
>>>
>>> My question is --- Is there anything I, as a user of an application
>>> package that is out-of-date with respect to the latest Python, can do to
>>> help in this process of bringing an application  up-to-date?
>>>
>>> --V. Stokes
>>>     
>>
>>   
> Note, again John, my question was about how I might assist (help) with 
> the updating of applications;

Your answers have been very helpful in determining exactly what your 
problem is; thank you.

> but, thank you for your interest in this.
> Perhaps, only the owner/responsible programmer for the application can 
> create a Windows installer,

Given a source distribution, a suitable C++ compiler, and the suspension 
of Murphy's Law, anyone should be able to (a) install it on their own 
machine (b) make a Windows installer.


> or perhaps others could assist with this --- 

Perhaps indeed ...

> this is what my question was about. I would be glad to assist if 
> possible :-)

Suggestions:

(1) contact the pyODE maintainer and ask, or check out the project's 
forums on sourceforge

(2) if you have a C++ compiler on your Windows box: get the source 
distribution, unpack it, ensure that the ODE_BASE in the setup.py points 
to your (existing) ODE 0.7 installation, do
     \python26\python setup.py install
and stand well back.

I have just tried this and got a ton of warnings from the compile and 3 
errors from the link:

build\lib.win32-2.6\ode.pyd : fatal error LNK1120: 3 unresolved externals
error: command '"C:\Program Files\Microsoft Visual Studio 
9.0\VC\BIN\link.exe"' failed with exit status 1120

C++ is not my bag and it's way past bedtime here, so I'll just paste in 
  the link output in the hope that someone can spot the problem:

C:\Program Files\Microsoft Visual Studio 9.0\VC\BIN\link.exe /DLL 
/nologo /INCREMENTAL:NO /LIBPATH:C:\ode\ode-0.7\lib\releaselib 
/LIBPATH:C:\python26\libs /LIBPATH:C:\python26\PCbuild ode.lib 
user32.lib /EXPORT:initode build\temp.win32-2.6\Release\ode_trimesh.obj 
/OUT:build\lib.win32-2.6\ode.pyd 
/IMPLIB:build\temp.win32-2.6\Release\ode.lib 
/MANIFESTFILE:build\temp.win32-2.6\Release\ode.pyd.manifest 
/NODEFAULTLIB:LIBCMT

    Creating library build\temp.win32-2.6\Release\ode.lib and object 
build\temp.win32-2.6\Release\ode.exp

ode.lib(error.obj) : error LNK2019: unresolved external symbol __iob 
referenced in function "void __cdecl printMessage(int,char const *,char 
const *,char *)" (?printMessage@@YAXHPBD0PAD at Z)

ode.lib(convex.obj) : error LNK2001: unresolved external symbol __iob

ode.lib(convex.obj) : error LNK2019: unresolved external symbol "public: 
void __thiscall std::_String_base::_Xran(void)const " 
(?_Xran at _String_base@std@@QBEXXZ) referenced in function "public: class 
std::basic_string<char,struct std::char_traits<char>,class 
std::allocator<char> > & __thiscall std::basic_string<char,struct 
std::char_traits<char>,class std::allocator<char> >::erase(unsigned 
int,unsigned int)" 
(?erase@?$basic_string at DU?$char_traits at D@std@@V?$allocator at D@2@@std@@QAEAAV12 at II@Z)

ode.lib(convex.obj) : error LNK2019: unresolved external symbol "public: 
void __thiscall std::_String_base::_Xlen(void)const " 
(?_Xlen at _String_base@std@@QBEXXZ) referenced in function "protected: 
bool __thiscall std::basic_string<char,struct 
std::char_traits<char>,class std::allocator<char> >::_Grow(unsigned 
int,bool)" 
(?_Grow@?$basic_string at DU?$char_traits at D@std@@V?$allocator at D@2@@std@@IAE_NI_N at Z)

build\lib.win32-2.6\ode.pyd : fatal error LNK1120: 3 unresolved externals

Cheers, John


From python at mrabarnett.plus.com  Sun Jul 19 11:52:45 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 16:52:45 +0100
Subject: Getting a Form To Work
In-Reply-To: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>
References: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>
Message-ID: <4A63414D.20408@mrabarnett.plus.com>

Victor Subervi wrote:
> Hi;
> I have the following in a *.py page for the Web:
> 
> from primeNumbers import primeNumbers
> 
> try:
>   num = form.getfirst('num')
> except:
>   num = ''
>   msg = "Oops"
> 
> print "Content-Type: text/html"
> print
> print """
> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" 
> "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
> <head xmlns="http://www.w3.org/1999/xhtml">
> </head>
> """
> if num != '':
>   try:
>     num = round(float(num))
>     roots = primeNumbers(num)
>     print roots
>   except:
>     msg += "We're sorry! You entered something that is not a number. 
> Please try again.<br />\n"
>     num = ''
> if num == '':
>   print msg
>   print "Num:", num

You get here if num == '', so you're printing out an empty string!

BTW, try not to use bare excepts.

>   print """
> <form action="http://13gems.com/test-Calculators_frame.py" method="post">
> <input type="text" name="num" size="20" maxlength="20" value="Enter 
> number here..." onfocus="this.value=''" />
> <input type="image" src="http://13gems.com/images/search.jpg" 
> name="search" id="search" />
> </form>
> """
> print '</body></html>\n'
> 
> Now, "Oops" never gets printed, nor does the variable num (although a 
> blank space appears to print). I am calling the very page to which the 
> form sends its values. Assuming the imported module works, why don?t I 
> get anything printed?
> 



From hendrik at microcorp.co.za  Sun Jul 19 12:07:54 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 19 Jul 2009 18:07:54 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <1248009501.29158.1325749595@webmail.messagingengine.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<200907191147.07949.mail@microcorp.co.za>
	<1248009501.29158.1325749595@webmail.messagingengine.com>
Message-ID: <200907191807.55071.hendrik@microcorp.co.za>

On Sunday 19 July 2009 15:18:21 python at bdurham.com wrote:
> Hi Hendrik,

> > If anybody is interested I will attach the code here. It is not a big
> > module.
>
> I am interested in seeing your code and would be grateful if you shared
> it with this list.

All right here it is.

Hope it helps

- Hendrik
-------------- next part --------------
A non-text attachment was scrubbed...
Name: netstring.py
Type: application/x-python
Size: 3474 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/e45876ef/attachment.bin>

From python at bdurham.com  Sun Jul 19 12:09:12 2009
From: python at bdurham.com (python at bdurham.com)
Date: Sun, 19 Jul 2009 12:09:12 -0400
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <200907191807.55071.hendrik@microcorp.co.za>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<200907191147.07949.mail@microcorp.co.za>
	<1248009501.29158.1325749595@webmail.messagingengine.com>
	<200907191807.55071.hendrik@microcorp.co.za>
Message-ID: <1248019752.28310.1325763043@webmail.messagingengine.com>

>> I am interested in seeing your code and would be grateful if you shared it with this list.

> All right here it is. Hope it helps.

Hendrik,

Thank you very much!! (I'm not the OP, but found this thread
interesting)

Best regards,
Malcolm


From piet at cs.uu.nl  Sun Jul 19 13:08:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 19:08:58 +0200
Subject: A little help with pexpect
References: <d5f4fbbf-82fb-453c-a4d6-f4708f0bd46e@m11g2000yqh.googlegroups.com>
	<m2ws64pw2i.fsf@cs.uu.nl>
Message-ID: <m2tz18ob11.fsf@cs.uu.nl>

>>>>> Piet van Oostrum <piet at cs.uu.nl> (PvO) wrote:
[snip]
>PvO> You can also consider using paramiko instead of pexpect. 
[snip]
>>>>> chan = t.open_session()
>>>>> chan.exec_command('cat')
>>>>> chan.send('abcdefghijklmn\n')

In a real program it is better to use sendall here, as send may decide
to send only part of its argument (the result will tell how many bytes
have been sent).
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From fft1976 at gmail.com  Sun Jul 19 13:33:39 2009
From: fft1976 at gmail.com (fft1976)
Date: Sun, 19 Jul 2009 10:33:39 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
Message-ID: <361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>

On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:

> E.g. the number system: In many Lisp
> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> it returns "0.6666666666", which will result in lots of fun for porting
> applications written for Python <= 2.6.

How do you explain that something as inferior as Python beat Lisp in
the market place despite starting 40 years later.


From python at mrabarnett.plus.com  Sun Jul 19 14:06:35 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 19:06:35 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <4A6360AB.4060003@mrabarnett.plus.com>

fft1976 wrote:
> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
> 
>> E.g. the number system: In many Lisp
>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
>> it returns "0.6666666666", which will result in lots of fun for porting
>> applications written for Python <= 2.6.
> 
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

It's all part of a Dutch conspiracy to take over the world! :-)


From python at mrabarnett.plus.com  Sun Jul 19 14:13:13 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 19:13:13 +0100
Subject: Getting a Form To Work
In-Reply-To: <4dc0cfea0907191034h2146a185o5691b0ab705f3c8d@mail.gmail.com>
References: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>	
	<4A63414D.20408@mrabarnett.plus.com>
	<4dc0cfea0907191034h2146a185o5691b0ab705f3c8d@mail.gmail.com>
Message-ID: <4A636239.2010208@mrabarnett.plus.com>

Victor Subervi wrote:
> When the form comes up the first time, there is the default value for 
> num. When I fill in a number in the form and press send, even though the 
> form sends to itself (same page name), I would think it would read the 
> number sent. Here again is the code:
> 
> from primeNumbers import primeNumbers
> 
> try:
>   lang = form.getfirst('lang', 'en')
>   browser = form.getfirst('browser', 'all')
>   site = form.getfirst('site', 'bridge')
>   num = form.getfirst('num','')
> except:
>   pass
> 
> ourFile = string.split(__file__, "/")
> p = ourFile[len(ourFile) - 1]
> p = p[: - 9]
> site = ourFile[4][:-10]
> if site != '':
>   site = site[:-1]
> 
> print "Content-Type: text/html"
> print
> print """
> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" 
> "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
> <head xmlns="http://www.w3.org/1999/xhtml">
> </head>
> """
> if num != '':
>   num = round(float(num))
>   roots = primeNumbers(num)
>   print roots
> if num == '':
>   print """
> <form action="http://13gems.com/test-Calculators_frame.py" method="post">
> <input type="text" name="num" size="20" maxlength="20" value="Enter 
> number here..." onfocus="this.value=''" />
> <input type="image" src="http://13gems.com/images/search.jpg" 
> name="search" id="search" />
> </form>
> """
> print '</body></html>\n'
> 
> And why not use bare excepts? What is better?
> 
[snip]
An exception could be raised for a number of reasons, including
misspelling a name. You should catch only those exceptions you expect so
that others you don't expect, caused by bugs, will still be shown;
you'll then know there's a bug and can fix it.


From egarrulo at gmail.com  Sun Jul 19 14:22:30 2009
From: egarrulo at gmail.com (Elena)
Date: Sun, 19 Jul 2009 11:22:30 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <1542e10e-6ff0-43db-ab31-b73c0942ecf6@d32g2000yqh.googlegroups.com>

On Jul 19, 7:33?pm, fft1976 <fft1... at gmail.com> wrote:
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

To be mainstream a language has to fit in most programmers' minds.



From victorsubervi at gmail.com  Sun Jul 19 14:28:10 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 19 Jul 2009 20:28:10 +0200
Subject: Trouble With a Form
Message-ID: <4dc0cfea0907191128j4ed4e8det11d244769222b57e@mail.gmail.com>

Hi:
When the form comes up the first time, there is the default value for num.
When I fill in a number in the form and press send, even though the form
sends to itself (same page name), I would think it would read the number
sent. Here again is the code:

from primeNumbers import primeNumbers

try:
 lang = form.getfirst('lang', 'en')
 browser = form.getfirst('browser', 'all')
 site = form.getfirst('site', 'bridge')
 num = form.getfirst('num','')
except:
 pass

ourFile = string.split(__file__, "/")
p = ourFile[len(ourFile) - 1]
p = p[: - 9]
site = ourFile[4][:-10]
if site != '':
 site = site[:-1]

print "Content-Type: text/html"
print
print """
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<head xmlns="http://www.w3.org/1999/xhtml">
</head>
"""
if num != '':
 num = round(float(num))
 roots = primeNumbers(num)
 print roots
if num == '':
 print """
<form action="http://13gems.com/test-Calculators_frame.py" method="post">
<input type="text" name="num" size="20" maxlength="20" value="Enter number
here..." onfocus="this.value=''" />
<input type="image" src="http://13gems.com/images/search.jpg" name="search"
id="search" />
</form>
"""
print '</body></html>\n'
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/3d2c1c8e/attachment.html>

From fb at frank-buss.de  Sun Jul 19 14:31:36 2009
From: fb at frank-buss.de (Frank Buss)
Date: Sun, 19 Jul 2009 20:31:36 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>

fft1976 wrote:

> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

Python is not that bad. Unlike Lisp, there is much less undefined behavior,
there is one free unique implementation on the 3 major platforms Linux,
Windows and MacOS X, which is stable, support multithreading and has a
default GUI library binding, which is difficult to find for Lisp (e.g. I
don't know of a free modern and stable Lisp implemenation with
mulithreading support for Windows, with a licence with which you can use it
in closed source commercial programs, like you can do with Python). Many
problems in the Lispbuilder mailing list are related to problems due to
different operating systems and Lisp implementations.

But maybe the most important point: The syntax looks simple compared to
Common Lisp (much less parentheses) and if you program in Python, it feels
easier for programmer newbies. As Sussman says: "undergraduate?s initial
experiences maximally productive". And this holds even for more experienced
programmers. If you know already a bit of C, it is easy to use Python, but
without the ability to do silly errors like writing out of array bounds (of
course, you can do this in Lisp, too, if you remember to set the safe mode
and if you use the right implementation). GC helps, too, to make the
programming task easier than in C. Some more arguments, e.g. 5 times less
program size than Java or C and more productive programmers:

http://www.artima.com/intv/speedP.html

(of course, an interview with Van Rossum might be a bit biased :-)

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From http  Sun Jul 19 14:51:17 2009
From: http (Paul Rubin)
Date: 19 Jul 2009 11:51:17 -0700
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
Message-ID: <7xljmk8q1m.fsf@ruckus.brouhaha.com>

Calroc <forman.simon at gmail.com> writes:
> I'm engaged presently in starting a school to teach programming from
> the ground up, based roughly on the curriculum outlined in the article
> I mentioned. ...
> I'm excited about formal methods because one, I just heard about them,

Formal methods are a big and complicated subject.  Right after you
heard about them is probably not the best time to start teaching them.
Better get to understand them yourself first.


From roy at panix.com  Sun Jul 19 15:09:28 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 19 Jul 2009 15:09:28 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <roy-362564.15092819072009@news.panix.com>

In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
 Frank Buss <fb at frank-buss.de> wrote:
 
> there is one free unique implementation on the 3 major platforms Linux,
> Windows and MacOS X

Most people would still consider Solaris to be a "major platform".


From rickbking at comcast.net  Sun Jul 19 15:32:16 2009
From: rickbking at comcast.net (Rick King)
Date: Sun, 19 Jul 2009 15:32:16 -0400
Subject: uniicode and executing a process with subprocess.call,
	or 	os.system
In-Reply-To: <50697b2c0907181606n2af8577ew3ad178f0463fa2d8@mail.gmail.com>
References: <4A624D1C.5010503@comcast.net>
	<50697b2c0907181606n2af8577ew3ad178f0463fa2d8@mail.gmail.com>
Message-ID: <4A6374C0.3000701@comcast.net>

Thanks. I looked around for alternatives but didn't find this one.
Rick

Chris Rebert wrote:
> On Sat, Jul 18, 2009 at 3:30 PM, Rick King<rickbking at comcast.net> wrote:
>   
>> Hello,
>> I want to copy files using subprocess.call or os.system where the file names
>> are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. Windows
>> stores all the file names in unicode so they are displayed ok in explorer,
>> and I can read them into my program with listdir(u'.'), etc. and work with
>> the names in the program.
>>     
>
> You should try one of the copying functions in the shutil module
> instead, it'll be much simpler than using subprocess:
> http://docs.python.org/library/shutil.html
>
> Cheers,
> Chris
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/cb8e1bb8/attachment.html>

From tjreedy at udel.edu  Sun Jul 19 16:01:26 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 19 Jul 2009 16:01:26 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <roy-362564.15092819072009@news.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
Message-ID: <h3vu2m$um2$1@ger.gmane.org>

Roy Smith wrote:
> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>  Frank Buss <fb at frank-buss.de> wrote:
>  
>> there is one free unique implementation on the 3 major platforms Linux,
>> Windows and MacOS X
> 
> Most people would still consider Solaris to be a "major platform".

?? I do not, but I have no idea what comes in 4th after the other three 
by whatever metric.



From stef.mientki at gmail.com  Sun Jul 19 16:15:01 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 19 Jul 2009 22:15:01 +0200
Subject: any suggestions to synchronize typed text and speech ?
Message-ID: <4A637EC5.4010701@gmail.com>

hello,

I'm using Scintilla as a wxPython widget with great pleasure.
I now have an application where I want to make notes during a conversation,
but also want to record the speech during that conversation.
I'm using Scintilla as a wxPython widget for editing and PyAudio for the 
speech recording,
until so far everything works fine.
 
Here the problem part:
I need to synchronize the typed text with the sound during playback.
So if I click somewhere in the sound recording,
the line of text, typed that moment should be highlighted.
And vise versa, if the cursor in the text is moved and some special key 
is pressed,
the sound starting 10 or 20seconds earlier should be playbacked.

I though of adding bookmarks (because these are fixed in the text), and 
keep a list of bookmarks and sound pointers.
This idea should work, but there are only 31 bookmarks.

Any other suggestions ?

thanks,
Stef Mientki


From emile at fenx.com  Sun Jul 19 17:16:38 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 19 Jul 2009 14:16:38 -0700
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h3vu2m$um2$1@ger.gmane.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>	<roy-362564.15092819072009@news.panix.com>
	<h3vu2m$um2$1@ger.gmane.org>
Message-ID: <h402aa$9vf$1@ger.gmane.org>

On 7/19/2009 1:01 PM Terry Reedy said...
> Roy Smith wrote:
>> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>>  Frank Buss <fb at frank-buss.de> wrote:
>>  
>>> there is one free unique implementation on the 3 major platforms Linux,
>>> Windows and MacOS X
>>
>> Most people would still consider Solaris to be a "major platform".
> 
> ?? I do not, but I have no idea what comes in 4th after the other three 
> by whatever metric.
> 

one metric calls fourth as the iPhone OS...

http://marketshare.hitslink.com/report.aspx?qprid=8&qptimeframe=Y&qpsp=2009&qpmr=100&qpdt=1&qpct=0&qpob=UV%20DESC

Emile



From pavlovevidence at gmail.com  Sun Jul 19 17:46:42 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sun, 19 Jul 2009 14:46:42 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>

On Jul 19, 10:33?am, fft1976 <fft1... at gmail.com> wrote:
> On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:
>
> > E.g. the number system: In many Lisp
> > implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> > "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> > it returns "0.6666666666", which will result in lots of fun for porting
> > applications written for Python <= 2.6.
>
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

There was no reason to crosspost this here--looking at the original
thread on comp.lang.lisp it seems they were doing a surprisingly good
job discussing the issue.

I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
with a flamewar in another thread (LISP vs PROLOG vs HASKELL).


Carl Banks


From casevh at gmail.com  Sun Jul 19 18:05:33 2009
From: casevh at gmail.com (casevh)
Date: Sun, 19 Jul 2009 15:05:33 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com> 
	<4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com> 
	<4ae1e16f-124b-49c8-8364-36c59419be9b@d32g2000yqh.googlegroups.com>
Message-ID: <ac459e66-81c1-4672-a5fa-ebed4987c298@l5g2000pra.googlegroups.com>

GMPY 1.10 beta is now available. This version fixes an issue where
very large objects would be cached for reuse instead of being freed.

Source code and Windows installers may be found at
http://code.google.com/p/gmpy/downloads/list

casevh


From vippstar at gmail.com  Sun Jul 19 18:54:17 2009
From: vippstar at gmail.com (vippstar)
Date: Sun, 19 Jul 2009 15:54:17 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <f17a63a6-0a61-4e36-be38-6f0402f1f5ac@j32g2000yqh.googlegroups.com>

On Jul 19, 9:31?pm, Frank Buss <f... at frank-buss.de> wrote:
> fft1976 wrote:
> > How do you explain that something as inferior as Python beat Lisp in
> > the market place despite starting 40 years later.
<snip>
> But maybe the most important point: The syntax looks simple compared to
> Common Lisp (much less parentheses)
hahaha.


From tundra at tundraware.com  Sun Jul 19 19:29:07 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Sun, 19 Jul 2009 18:29:07 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
Message-ID: <lqmcj6-qij.ln1@ozzie.tundraware.com>

Carl Banks wrote:
> On Jul 19, 10:33 am, fft1976 <fft1... at gmail.com> wrote:
>> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
>>
>>> E.g. the number system: In many Lisp
>>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
>>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
>>> it returns "0.6666666666", which will result in lots of fun for porting
>>> applications written for Python <= 2.6.
>> How do you explain that something as inferior as Python beat Lisp in
>> the market place despite starting 40 years later.
> 
> There was no reason to crosspost this here--looking at the original
> thread on comp.lang.lisp it seems they were doing a surprisingly good
> job discussing the issue.
> 
> I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
> with a flamewar in another thread (LISP vs PROLOG vs HASKELL).
> 
> 
> Carl Banks

This is an incredibly important discussion and is much weaker because
it does not also include Pascal, BASIC, Ada, Oberon and Forth. In fact,
picking a computer language is the most important discussion in
Computer Science and eclipses even P=NP? in significance. I sure hope
we can keep this thread going for a few months. For guidance, see:


   http://www.tundraware.com/Technology/How-To-Pick-A-Programming-Language/



-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From marcusw at cox.net  Sun Jul 19 19:32:02 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sun, 19 Jul 2009 19:32:02 -0400
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <mailman.3406.1248034495.8015.python-list@python.org>
References: <mailman.3406.1248034495.8015.python-list@python.org>
Message-ID: <h40adj$bv6$1@adenine.netfront.net>

On 7/19/2009 4:15 PM, Stef Mientki wrote:
> hello,
> 
> I'm using Scintilla as a wxPython widget with great pleasure.
> I now have an application where I want to make notes during a conversation,
> but also want to record the speech during that conversation.
> I'm using Scintilla as a wxPython widget for editing and PyAudio for the 
> speech recording,
> until so far everything works fine.
> 
> Here the problem part:
> I need to synchronize the typed text with the sound during playback.
> So if I click somewhere in the sound recording,
> the line of text, typed that moment should be highlighted.
> And vise versa, if the cursor in the text is moved and some special key 
> is pressed,
> the sound starting 10 or 20seconds earlier should be playbacked.
> 
> I though of adding bookmarks (because these are fixed in the text), and 
> keep a list of bookmarks and sound pointers.
> This idea should work, but there are only 31 bookmarks.
> 
> Any other suggestions ?
> 
> thanks,
> Stef Mientki
That sounds like a very specialized type of thing, which only the few 
people with experience with wxPython, PyAudio, and Scintilla could help 
you with...

But you might try having a dictionary with notes and associated times, 
or just give each note a four-digit ID number at the beginning of it 
when it's entered and use that in the dictionary (to keep keys shorter). 
Or you could just do a little hack and increase the number of bookmarks 
allowed (seeing as source is available) :p

Marcus


From http  Sun Jul 19 19:35:01 2009
From: http (Paul Rubin)
Date: 19 Jul 2009 16:35:01 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
	<h3vu2m$um2$1@ger.gmane.org>
	<mailman.3407.1248038041.8015.python-list@python.org>
Message-ID: <7xiqho1c2i.fsf@ruckus.brouhaha.com>

Emile van Sebille <emile at fenx.com> writes:
> >> Most people would still consider Solaris to be a "major platform".
> > ?? I do not, but I have no idea what comes in 4th after the other
> > three by whatever metric.
> one metric calls fourth as the iPhone OS...
> http://marketshare.hitslink.com/report.aspx?qprid=8...

That metric is clearly wrong.  The #1 platform OS platform in terms of
number of units shipped is Javacard, which is in the SIM cards of
billions of GSM phones.


From pavlovevidence at gmail.com  Sun Jul 19 20:45:01 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sun, 19 Jul 2009 17:45:01 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com> 
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
Message-ID: <1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>

On Jul 19, 4:29?pm, Tim Daneliuk <tun... at tundraware.com> wrote:
> Carl Banks wrote:
> > On Jul 19, 10:33 am, fft1976 <fft1... at gmail.com> wrote:
> >> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
>
> >>> E.g. the number system: In many Lisp
> >>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> >>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> >>> it returns "0.6666666666", which will result in lots of fun for porting
> >>> applications written for Python <= 2.6.
> >> How do you explain that something as inferior as Python beat Lisp in
> >> the market place despite starting 40 years later.
>
> > There was no reason to crosspost this here--looking at the original
> > thread on comp.lang.lisp it seems they were doing a surprisingly good
> > job discussing the issue.
>
> > I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
> > with a flamewar in another thread (LISP vs PROLOG vs HASKELL).
>
> > Carl Banks
>
> This is an incredibly important discussion

It might be an important question but a discussion on Usenet about it
is utterly useless.


> and is much weaker because
> it does not also include Pascal, BASIC, Ada, Oberon and Forth.

In the same way that a movie is weaker because the director edited out
the bad scenes.


> In fact,
> picking a computer language is the most important discussion in
> Computer Science and eclipses even P=NP? in significance. I sure hope
> we can keep this thread going for a few months.

Please feel free to extend this flame-war along for a few months on
comp.lang.lisp.  Not here.


Carl Banks


From marek at xivilization.net  Sun Jul 19 20:51:49 2009
From: marek at xivilization.net (Marek Kubica)
Date: Mon, 20 Jul 2009 02:51:49 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
Message-ID: <20090720025149.326f0cfc@halmanfloyd.lan.local>

On Sun, 19 Jul 2009 15:09:28 -0400
Roy Smith <roy at panix.com> wrote:

> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>  Frank Buss <fb at frank-buss.de> wrote:
>  
> > there is one free unique implementation on the 3 major platforms
> > Linux, Windows and MacOS X
> 
> Most people would still consider Solaris to be a "major platform".

Depends on who you ask. On the desktop it doesn't matter at all
(fortunately, since everytime I work on Solaris I'm entering a world of
pain which is just slowly getting better with OpenSolaris), on the
server it (and other propietary Unices) is losing ground compared to
the free Unices.

But ok, let's say 3 major platforms: Unix, Windows and Mac OS X. Mac OS
X is formally a Unix but everything with GUI is non-Unix'y so it can be
considered a separate platform.

regards,
Marek


From marek at xivilization.net  Sun Jul 19 20:54:13 2009
From: marek at xivilization.net (Marek Kubica)
Date: Mon, 20 Jul 2009 02:54:13 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1542e10e-6ff0-43db-ab31-b73c0942ecf6@d32g2000yqh.googlegroups.com>
Message-ID: <20090720025413.12eb7fbf@halmanfloyd.lan.local>

On Sun, 19 Jul 2009 11:22:30 -0700 (PDT)
Elena <egarrulo at gmail.com> wrote:

> On Jul 19, 7:33?pm, fft1976 <fft1... at gmail.com> wrote:
> > How do you explain that something as inferior as Python beat Lisp in
> > the market place despite starting 40 years later.
> 
> To be mainstream a language has to fit in most programmers' minds.

Sometimes I wonder whether Python is not too complex for "most
programmers", since "most programmers" use Java, which is heavily
mainstream. Interesting whether it is in spite of the ridiculous
limitations or because of these. Probably a mix of both.

regards,
Marek



From research at johnohagan.com  Sun Jul 19 21:44:44 2009
From: research at johnohagan.com (John O'Hagan)
Date: Mon, 20 Jul 2009 01:44:44 +0000
Subject: question on input function
In-Reply-To: <346922.15108.qm@web56908.mail.re3.yahoo.com>
References: <346922.15108.qm@web56908.mail.re3.yahoo.com>
Message-ID: <200907200144.44417.research@johnohagan.com>

On Mon, 20 Jul 2009, Richel Satumbaga wrote:
> I am just learning python then I encountered an certain point in terms of
> using the input function of python. the source code:
>                        eq = input("enter an equation:");
>                        print " the result is : ";
>
>
> the output seen in the command window:
>
> enter an equation:[m*x+b for m in (0,10,1),for x in (1,11,1), for b in
> (2,12,1)]
>
> Traceback (most recent call last):
>   File "C:/Python26/try", line 1, in <module>
>     eq = input("enter an equation:");
>   File "<string>", line 1
>     [m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]
>                                ^
> SyntaxError: invalid syntax

[...]

It's the extra commas in your list comprehension.This should work:

[m*x+b for m in (0,10,1) for x in (1,11,1) for b in (2,12,1)]

HTH,

John




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090720/273f60b8/attachment.html>

From rlsatumbaga at yahoo.com  Sun Jul 19 22:07:07 2009
From: rlsatumbaga at yahoo.com (Richel Satumbaga)
Date: Sun, 19 Jul 2009 19:07:07 -0700 (PDT)
Subject: question on input function
Message-ID: <346922.15108.qm@web56908.mail.re3.yahoo.com>

I am just learning python then I encountered an certain point in terms of using the input function of python.
the source code:
?????????????????????? eq = input("enter an equation:");
?????????????????????? print " the result is : ";


the output seen in the command window:
>>>
enter an equation:[m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]

Traceback (most recent call last):
? File "C:/Python26/try", line 1, in <module>
??? eq = input("enter an equation:");
? File "<string>", line 1
??? [m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]
?????????????????????????????? ^
SyntaxError: invalid syntax

????????????????? Is there any other way to enter those? or it must be coded in the source code?
If in source code is it like in matlab where one can type:

x = [0:1:10]; 

to define the range of x which is form 0 to 10 with the increment of? 1.

Thanks 

Ann



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/1e922a04/attachment.html>

From roy at panix.com  Sun Jul 19 22:07:34 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 19 Jul 2009 22:07:34 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
	<20090720025149.326f0cfc@halmanfloyd.lan.local>
Message-ID: <roy-CF08FF.22073419072009@news.panix.com>

In article <20090720025149.326f0cfc at halmanfloyd.lan.local>,
 Marek Kubica <marek at xivilization.net> wrote:

> > > there is one free unique implementation on the 3 major platforms
> > > Linux, Windows and MacOS X
> > 
> > Most people would still consider Solaris to be a "major platform".
> 
> Depends on who you ask. On the desktop it doesn't matter at all
> (fortunately, since everytime I work on Solaris I'm entering a world of
> pain which is just slowly getting better with OpenSolaris), on the
> server it (and other propietary Unices) is losing ground compared to
> the free Unices.

Clearly, there's not much (if any) Solaris on the desktop.  But it's sure 
alive and kicking in the server world.

One of the things I like about Python is not just how portable is it is, 
but how easy it is to build and deploy.  We build our product on Windows, N 
different Linux distros, Solaris, HPUX, AIX, and OSX.  I've built Python 
for all of those platforms.  Then, I checked the install areas into 
Perforce.  Deploying is as simple as checking out the right sandbox.

We've gone through the same exercise for Perl.  That was a lot more 
painful.


From fatkinson at mishmash.com  Sun Jul 19 22:22:37 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Sun, 19 Jul 2009 19:22:37 -0700
Subject: Final Project
Message-ID: <v6l765lvk1tf6l63gkfjli64boo394cl7a@4ax.com>

	I'm looking for some ideas here.  

	I think I've mentioned I am taking a course in Python and PHP.
The professor wants each of us to pick a project to write in both
languages.  It has to be something fairly complex and I'd like for it
to be something that would be useful on my Web site(s).  

	I would be grateful for any and all suggestions.  

	Regards, 





						Fred 


From clp2 at rebertia.com  Sun Jul 19 22:44:45 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 19 Jul 2009 19:44:45 -0700
Subject: question on input function
In-Reply-To: <346922.15108.qm@web56908.mail.re3.yahoo.com>
References: <346922.15108.qm@web56908.mail.re3.yahoo.com>
Message-ID: <50697b2c0907191944i43d14c85m270bd391e366ec21@mail.gmail.com>

On Sun, Jul 19, 2009 at 7:07 PM, Richel Satumbaga<rlsatumbaga at yahoo.com> wrote:
> I am just learning python then I encountered an certain point in terms of
> using the input function of python.
> the source code:
> ?????????????????????? eq = input("enter an equation:");
> ?????????????????????? print " the result is : ";
>
>
> the output seen in the command window:
>>>>
> enter an equation:[m*x+b for m in (0,10,1),for x in (1,11,1), for b in
> (2,12,1)]
>
> Traceback (most recent call last):
> ? File "C:/Python26/try", line 1, in <module>
> ??? eq = input("enter an equation:");
> ? File "<string>", line 1
> ??? [m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]
> ?????????????????????????????? ^
> SyntaxError: invalid syntax
>
> ????????????????? Is there any other way to enter those? or it must be coded
> in the source code?
> If in source code is it like in matlab where one can type:
>
> x = [0:1:10];
>
> to define the range of x which is form 0 to 10 with the increment of? 1.

First, commas between the "for"s are not permitted, which gives us:

[m*x+b for m in (0,10,1) for x in (1,11,1) for b in (2,12,1)]

However, in Python, (i, j, k) is just a tuple (MATLAB: 1D matrix) of
the items i, j, and k.
What you want is a range, which is understandably created using the
range() function.
A step of 1 and a start of 0 are the defaults, and the stop value is
always excluded, so the code becomes:

[m*x+b for m in range(11) for x in range(1,12) for b in range(2,13)]

Which should be what you want.

For further explanation of the range() function:
range(b) - the numbers from 0 to b-1 with a step of 1
range(a,b) - the numbers from a to b-1 with a step of 1
range(a,b,c) - the numbers from a to b-1 with a step of c

Hope that helps.

Cheers,
Chris
-- 
http://blog.rebertia.com


From denize.paul at gmail.com  Sun Jul 19 22:57:50 2009
From: denize.paul at gmail.com (pdenize)
Date: Sun, 19 Jul 2009 19:57:50 -0700 (PDT)
Subject: Managing non-ascii filenames in python
Message-ID: <60a305de-0552-4f77-9051-d87149d308c7@y10g2000prg.googlegroups.com>

I created the following filename in windows just as a test -
?D?n?ld?s? N?ph?ws? deg?.txt
The quotes are non -ascii, many non english characters, long hyphen
etc.

Now in DOS I can do a directory and it translates them all to
something close.
"D?n?ld'sT N?ph?ws" deg?.txt

I thought the correct way to do this in python would be to scan the
dir
files=os.listdir(os.path.dirname( os.path.realpath( __file__ ) ))

then print the filenames
for filename in files:
  print filename

but as expected teh filename is not correct - so correct it using the
file sysytems encoding

  print filename.decode(sys.getfilesystemencoding())

But I get
UnicodeEncodeError: 'charmap' codec can't encode character u'\u2014'
in position 6: character maps to <undefined>

All was working well till these characters came along

I need to be able to write (a representation) to the screen (and I
don't see why I should not get something as good as DOS shows).

Write it to an XML file in UTF-8

and write it to a text file and be able to read it back in.
Again I was supprised that this was also difficult - it appears that
the file also wanted ascii.  Should I have to open the file in binary
for write (I expect so) but then what encoding should I write in?

I have been beating myself up with this for weeks as I get it working
then come across some outher character that causes it all to stop
again.

Please help.


From mensanator at aol.com  Mon Jul 20 00:12:35 2009
From: mensanator at aol.com (Mensanator)
Date: Sun, 19 Jul 2009 21:12:35 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com> 
	<4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com> 
	<4ae1e16f-124b-49c8-8364-36c59419be9b@d32g2000yqh.googlegroups.com> 
	<ac459e66-81c1-4672-a5fa-ebed4987c298@l5g2000pra.googlegroups.com>
Message-ID: <2c3e8fc0-e814-4020-bcfd-d3d02cc62dea@t13g2000yqt.googlegroups.com>

On Jul 19, 5:05?pm, casevh <cas... at gmail.com> wrote:
> GMPY 1.10 beta is now available. This version fixes an issue where
> very large objects would be cached for reuse instead of being freed.

Excellent! That explains the funny memory usage graph.

>
> Source code and Windows installers may be found athttp://code.google.com/p/gmpy/downloads/list
>

Test results:

import collatz_functions as cf
# imports gmpy
# the cf.Type12MH function does the equivalent
# of the pure Python version of the function
# using gmpy
import time

#3.1 gmpy 1.10 beta
#
t0 = time.time()
n=10
for k in range(1,n):
  for i in range(1,n-2):
    print((str(cf.gmpy.numdigits(cf.Type12MH(k,i))).zfill(n)),end=' ')
  print()
print()
t1 = time.time()

print(t1-t0)

# 3.1 pure Python
#
##t0 = time.time()
##n=10
##for k in range(1,n):
##  for i in range(1,n-2):
##    print((str(cf.gmpy.numdigits( \
##      2**(6*((i-1)*9**(k-1)+(9**(k-1)-1)//2+1)-1)-1  \
##      )).zfill(n)),end=' ')
##  print()
##print()
##t1 = time.time()
##
##print(t1-t0)


##  3.1 gmpy 1.10 alpha
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##3.32299995422
## funny memory usage display, different between 2.6 & 3.1, but funny
regardless,
## memory remains allocated (~700 MB) when program halts

##  3.1 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##338.832000017
## memory usage seems normal, runs slow enough to observe memory being
allocated
## and freed and remains freed when program halts

##  2.6 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##aborted after ONE FULL WEEK of processing (only 8 of 9 rows
completed)

##  Something funny happened here. By the time I ran this test, there
##  were 14 orphaned copies of pythonw.exe present, at least one of
which
##  was still running along with the real pair executing the program.
Yet
##  the Performance only registered ~50%. Normally, this would be 100%
if
##  two programs were running. Pure Python is a LOT slower than gmpy,
##  but not THAT slow. These orphaned processes may be a Python 3.1
issue.

##===================================================================

## 3.1 gmpy 1.10 beta
##
##  0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##  0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##  0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##  0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##  0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##  0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##  0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##  0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##  0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##  2.41799998283
## memory usage now appears normal, no more allocated memory when
program halts
## and it's so fast all we see on Performance graph is a small blip,
much better
## than the 700-1400 MB it was allocating before.

## 3.1 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##339.611999989
## looks like gmpy about a 100 times faster. I knew there was a reason
I
## won't use Python without gmpy.

## 2.6 gmpy 1.10 beta
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##2.68400001526

## 2.6 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##338.987999916
## ah, that's more like it. no more pythonw.exe thrashing. I was
almost ready
## to drop version 2.6 like a live grenade, but that was based on some
other
## fault apparently. it may be 3.1 I have to drop.

I still got a single instance of an orphaned pythonw.exe, but this
happened during a quick attempt at provoking it during a 3.1 pure
Python test, so I have no reason to suspect gmpy (previously, I
thought it may be related to the memory leak).

I've got an idea on how to reliably provoke this which I'll try to
work up later (and won't even load gmpy to make sure it's not
involved).

> casevh



From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 20 01:11:17 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 20 Jul 2009 05:11:17 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>

On Sun, 19 Jul 2009 10:33:39 -0700, fft1976 wrote:

> On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:
> 
>> E.g. the number system: In many Lisp
>> implementations (/ 2 3) results in the fractional object 2/3. In Python
>> 2.6 "2 / 3" results in "0". Looks like with Python 3.1 they have fixed
>> it, now it returns "0.6666666666", which will result in lots of fun for
>> porting applications written for Python <= 2.6.
> 
> How do you explain that something as inferior as Python beat Lisp in the
> market place despite starting 40 years later.

http://www.jwz.org/doc/worse-is-better.html


Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing 
to do. It's the right thing to do if you're doing integer maths.


-- 
Steven


From fb at frank-buss.de  Mon Jul 20 01:18:01 2009
From: fb at frank-buss.de (Frank Buss)
Date: Mon, 20 Jul 2009 07:18:01 +0200
Subject: Final Project
References: <v6l765lvk1tf6l63gkfjli64boo394cl7a@4ax.com>
Message-ID: <1ctywmarsqqzd.y7fg69mkbshy$.dlg@40tude.net>

Fred Atkinson wrote:

> 	I'm looking for some ideas here.  
> 
> 	I think I've mentioned I am taking a course in Python and PHP.
> The professor wants each of us to pick a project to write in both
> languages.  It has to be something fairly complex and I'd like for it
> to be something that would be useful on my Web site(s).  
> 
> 	I would be grateful for any and all suggestions.  

Useful for your webpage depends very much on what you think what you need
and it is difficult to answer by others who don't know your needs.

E.g. useful for me was a Python Blender script to create wireframe and
solid models of platonic solids and a program for geodesic domes of
parametrized detail level:

http://www.frank-buss.de/shapeways/dome.py
http://www.shapeways.com/mydesign?user_id=19157

It is my first bigger Python program, so ideas how it could be improved are
welcome.

Would be an interesting project to create a renderer for it, which can
calculate this and other geometric figures as a CGI script to an image and
display the result in the browser. Try this in PHP and Python and write
about the experiences you made. Maybe don't forget to limit the access to
the webpage or the size of the output image, to avoid trouble with your
hosting provider, if you don't have your own server and anything slows down
because of your rendering task :-)

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From tundra at tundraware.com  Mon Jul 20 01:18:58 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Mon, 20 Jul 2009 00:18:58 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
	<1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
Message-ID: <jabdj6-qij.ln1@ozzie.tundraware.com>

Carl Banks wrote:
> On Jul 19, 4:29 pm, Tim Daneliuk <tun... at tundraware.com> wrote:
>> Carl Banks wrote:
>>> On Jul 19, 10:33 am, fft1976 <fft1... at gmail.com> wrote:
>>>> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
>>>>> E.g. the number system: In many Lisp
>>>>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
>>>>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
>>>>> it returns "0.6666666666", which will result in lots of fun for porting
>>>>> applications written for Python <= 2.6.
>>>> How do you explain that something as inferior as Python beat Lisp in
>>>> the market place despite starting 40 years later.
>>> There was no reason to crosspost this here--looking at the original
>>> thread on comp.lang.lisp it seems they were doing a surprisingly good
>>> job discussing the issue.
>>> I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
>>> with a flamewar in another thread (LISP vs PROLOG vs HASKELL).
>>> Carl Banks
>> This is an incredibly important discussion
> 
> It might be an important question but a discussion on Usenet about it
> is utterly useless.
> 
> 
>> and is much weaker because
>> it does not also include Pascal, BASIC, Ada, Oberon and Forth.
> 
> In the same way that a movie is weaker because the director edited out
> the bad scenes.
> 
> 
>> In fact,
>> picking a computer language is the most important discussion in
>> Computer Science and eclipses even P=NP? in significance. I sure hope
>> we can keep this thread going for a few months.
> 
> Please feel free to extend this flame-war along for a few months on
> comp.lang.lisp.  Not here.
> 
> 
> Carl Banks

Uh Carl ... are you familiar with the concept of mocking humor?

-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 01:54:57 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 02:54:57 -0300
Subject: file write IOError Invalid argument
References: <505868.24184.qm@web59308.mail.re1.yahoo.com>
Message-ID: <op.uxcqpvk8x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 16 Jul 2009 17:41:39 -0300, Robert Robert  
<robertrobert93 at yahoo.com> escribi?:

> I am trying to write a binary string to file on a windows network share.  
> I get an IOError. I've read that it is because the file size is too  
> large. I did a type( binaryString) and saw that it was type "str". So I  
> loop through it one by one element and use f.write to write to file, and  
> it worked without any error. However it took a long while to write to  
> file. I was wondering how I could split this binary string into N number  
> of chunks efficiently and write them to file.

some_string[i:i+BLOCK_SIZE]
returns a slice of the original string, starting at position i, with  
length BLOCK_SIZE.

-- 
Gabriel Genellina



From bob.martin at excite.com  Mon Jul 20 02:12:45 2009
From: bob.martin at excite.com (Bob Martin)
Date: Mon, 20 Jul 2009 06:12:45 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<mailman.3405.1248033697.8015.python-list@python.org>
Message-ID: <xVT8m.58560$OO7.36279@text.news.virginmedia.com>

in 121683 20090719 210126 Terry Reedy <tjreedy at udel.edu> wrote:
>Roy Smith wrote:
>> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>>  Frank Buss <fb at frank-buss.de> wrote:
>>
>>> there is one free unique implementation on the 3 major platforms Linux,
>>> Windows and MacOS X
>>
>> Most people would still consider Solaris to be a "major platform".
>
>?? I do not, but I have no idea what comes in 4th after the other three
>by whatever metric.

I think the OP means "major PC operating systems".  Those with a wider 
knowledge of the computer world would consider IBM's mainframe operating
systems to be deserving of the description "major".


From http  Mon Jul 20 02:13:15 2009
From: http (Paul Rubin)
Date: 19 Jul 2009 23:13:15 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
Message-ID: <7x4ot7rif8.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:
> Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing 
> to do. It's the right thing to do if you're doing integer maths.

I wonder whether 2/3 => ValueError is preferable.


From martin at v.loewis.de  Mon Jul 20 02:27:20 2009
From: martin at v.loewis.de (=?windows-1252?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Mon, 20 Jul 2009 08:27:20 +0200
Subject: Managing non-ascii filenames in python
In-Reply-To: <60a305de-0552-4f77-9051-d87149d308c7@y10g2000prg.googlegroups.com>
References: <60a305de-0552-4f77-9051-d87149d308c7@y10g2000prg.googlegroups.com>
Message-ID: <4a640e48$0$7445$9b622d9e@news.freenet.de>

> I thought the correct way to do this in python would be to scan the
> dir
> files=os.listdir(os.path.dirname( os.path.realpath( __file__ ) ))
> 
> then print the filenames
> for filename in files:
>   print filename
> 
> but as expected teh filename is not correct - so correct it using the
> file sysytems encoding
> 
>   print filename.decode(sys.getfilesystemencoding())
> 
> But I get
> UnicodeEncodeError: 'charmap' codec can't encode character u'\u2014'
> in position 6: character maps to <undefined>

As a starting point, you shouldn't be using byte-oriented APIs to
access files on Windows; the specific byte-oriented API is os.listdir,
when passed a directory represented as a byte string.

So try:

   dirname = os.path.dirname(os.path.realpath(__file__))
   dirname = dirname.decode(sys.getfilesystemencoding()
   files = os.listdir(dirname)

This should give you the files as Unicode strings.

> I need to be able to write (a representation) to the screen (and I
> don't see why I should not get something as good as DOS shows).

The command window (it's not really DOS anymore) uses the CP_OEMCP
encoding, which is not available in Python. This does all the
transliteration also, so you would have to write an extension module
if you want to get the same transliteration (or try to get to the
OEMCP encoding through ctypes).

If you can live with a simpler transliteration, try

  print filename.encode(sys.stdout.encoding, "replace")

> Write it to an XML file in UTF-8
> 
> and write it to a text file and be able to read it back in.
> Again I was supprised that this was also difficult - it appears that
> the file also wanted ascii.  Should I have to open the file in binary
> for write (I expect so) but then what encoding should I write in?

You need to tell us how precisely you tried to do this. My guess is:
if you now try again, with the filenames being Unicode strings, it
will work fairly well.

Regards,
Martin


From fb at frank-buss.de  Mon Jul 20 02:28:58 2009
From: fb at frank-buss.de (Frank Buss)
Date: Mon, 20 Jul 2009 08:28:58 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<mailman.3405.1248033697.8015.python-list@python.org>
	<xVT8m.58560$OO7.36279@text.news.virginmedia.com>
Message-ID: <1pk5i4u29maii.vcsqz0mmsyy5$.dlg@40tude.net>

Bob Martin wrote:

> I think the OP means "major PC operating systems".  Those with a wider 
> knowledge of the computer world would consider IBM's mainframe operating
> systems to be deserving of the description "major".

Maybe you are right, if you mean big machines. I know mainframes a bit and
there are interesting concepts, like hot-swapping of CPU modules and
mainframes are very reliable. But expensive, too. I know at least one
client, who wants to change it to some cheap Linux boxes, like Google
demonstrates it. If you take care (e.g. Xen virtualization for easier
computer changing and RAID harddisks, if a downtime of some hours might be
ok), it doesn't matter if one PC goes out of order.

But even on IBM mainframes you can install Linux or other Unix systems in
parallel to the usual operating systems for this machines, so except for
special cases, like embedded systems, the most installed and used operating
systems might be Unix-like systems and Windows. But looks like Python even
runs on more native operating systems for mainframes.

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From bob.martin at excite.com  Mon Jul 20 02:40:21 2009
From: bob.martin at excite.com (Bob Martin)
Date: Mon, 20 Jul 2009 06:40:21 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<mailman.3405.1248033697.8015.python-list@python.org>
	<xVT8m.58560$OO7.36279@text.news.virginmedia.com>
	<1pk5i4u29maii.vcsqz0mmsyy5$.dlg@40tude.net>
Message-ID: <pjU8m.58569$OO7.15871@text.news.virginmedia.com>

in 121708 20090720 072858 Frank Buss <fb at frank-buss.de> wrote:
>Bob Martin wrote:
>
>> I think the OP means "major PC operating systems".  Those with a wider
>> knowledge of the computer world would consider IBM's mainframe operating
>> systems to be deserving of the description "major".
>
>Maybe you are right, if you mean big machines. I know mainframes a bit and
>there are interesting concepts, like hot-swapping of CPU modules and
>mainframes are very reliable. But expensive, too. I know at least one
>client, who wants to change it to some cheap Linux boxes, like Google
>demonstrates it. If you take care (e.g. Xen virtualization for easier
>computer changing and RAID harddisks, if a downtime of some hours might be
>ok), it doesn't matter if one PC goes out of order.
>
>But even on IBM mainframes you can install Linux or other Unix systems in
>parallel to the usual operating systems for this machines, so except for
>special cases, like embedded systems, the most installed and used operating
>systems might be Unix-like systems and Windows. But looks like Python even
>runs on more native operating systems for mainframes.

Yes, a "platform" is really the combination of hardware architecture and operating system,
so Linux on Intel and Linux on 390 are different platforms.


From pavlovevidence at gmail.com  Mon Jul 20 03:08:31 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 20 Jul 2009 00:08:31 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com> 
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
	<1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
	<jabdj6-qij.ln1@ozzie.tundraware.com>
Message-ID: <77e91c9e-5487-427d-9300-3ad9015adf51@2g2000prl.googlegroups.com>

On Jul 19, 10:18?pm, Tim Daneliuk <tun... at tundraware.com> wrote:
> Uh Carl ... are you familiar with the concept of mocking humor?

You got me, lip hurts bad. :)


Carl Banks


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 03:29:17 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 04:29:17 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com>
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
Message-ID: <op.uxcu23j6x6zn5v@lepton.softlabbsas.com.ar>

En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac <alan.isaac at gmail.com>  
escribi?:

>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>> def apply2(itr, methodname, *args, **kwargs):
>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>     for item in itr:
>>>         f(item)
>
>
> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>> for obj in objects:
>>     getattr(obj, methodname)(*args, **kwargs)
>
>
> Are there any obvious considerations in choosing
> between those two?

The operator.methodcaller version is faster in my tests for large  
collections, but slightly slower when you have very few elements.

<code>
import operator
import timeit

class X:
   def method(self, x, y, **kw): pass

def apply1(itr, methodname, *args, **kwargs):
     for item in itr:
         getattr(item, methodname)(*args, **kwargs)

def apply2(itr, methodname, *args, **kwargs):
     f = operator.methodcaller(methodname, *args, **kwargs)
     for item in itr:
         f(item)

L=[X() for _ in range(3000)]
apply1(L,'method', 1, 2, foo=3)
apply2(L,'method', 1, 2, foo=3)

timeit.timeit(setup="from __main__ import apply1,apply2,L",  
stmt="apply1(L,'method', 1, 2, foo=3)", number=1000)
timeit.timeit(setup="from __main__ import apply1,apply2,L",  
stmt="apply2(L,'method', 1, 2, foo=3)", number=1000)
</code>

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 20 03:50:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 04:50:15 -0300
Subject: Mechanize not recognized by py2exe
References: <4A60C81F.7080707@comcast.net>
Message-ID: <op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 15:51:11 -0300, Stephen M. Olds <smolds at comcast.net>  
escribi?:

> I have a Python script getData.py that uses Mechanize, and runs fine  
> under the
> interpreter. It was installed using easy_install - and the install  
> seemed to
> indicate it was completed.
>
> The problem is, when I try to compile it using py2exe while in the  
> folder of the
> script, and using the run line command:
>
> python getData.py py2exe
>
> I get the warning: "Import error: No Module named mechanize"...
>
> I checked the environmental path and find the following:
> %SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program  
> Files (x86)\Python;C:\Python25\Lib\site-packages;C:\Program
> Files (x86)\Common Files\Adobe\AGL

The system PATH is irrelevant here - it's only used by Windows to locate  
the Python executable. I don't see a reason to list  
C:\Python25\Lib\site-packages here.
You're mostly interested in sys.path instead (that is, the 'path'  
attribute in the 'sys' Python module)

> I did a search for mechanize and find an egg file in  
> C:\Python25\Lib\site-packages
> named mechanize-0.1.7b-py2.5.
>
> Not really understanding the "egg" thing, what do I have here that needs  
> to be
> done?

I'm not an egg expert either, and I try to avoid them as a plague. But I  
*think* you can delete the .egg and re-install it using easy_install with  
the -Z option.

-- 
Gabriel Genellina



From greg at cosc.canterbury.ac.nz  Mon Jul 20 04:00:14 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Mon, 20 Jul 2009 20:00:14 +1200
Subject: tough-to-explain Python
In-Reply-To: <6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
Message-ID: <7cimf0F27u23eU1@mid.individual.net>

Calroc wrote:

> It may be that flawless software is an unreachable asymptote, like the
> speed of light for matter, but I'm (recently!) convinced that it's a
> goal worthy of exploration and effort.

Seems to me that once you get beyond the toy program
stage and try to apply correctness proving to real
world programming problems, you run up against the
problem of what exactly you mean by "correct".

Once the requirements get beyond a certain level of
complexity, deciding whether the specifications
themselves are correct becomes just as difficult as
deciding whether the program meets them.

Then there's the fact that very often we don't
even know what the exact requirements are, and it's
only by trying to write and use the program that
we discover what they really are -- or at least,
get a better idea of what they are, because the
process is usually iterative, with no clear end
point.

So in theory, correctness proofs are a fine idea,
and might even be doble on a small scale, but the
real world is huge and messy!

> Just because it's unattainable doesn't make it undesirable.  And who
> knows? Maybe the horse will learn to sing.

Striving to find ways of writing less bugs is a
worthy goal, but I think of it more in terms of
adopting patterns of thought and programming that
make it more likely you will write code that does
what you had in mind, rather than a separate
"proof" process that you go through afterwards.

-- 
Greg


From stef.mientki at gmail.com  Mon Jul 20 05:34:09 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Mon, 20 Jul 2009 11:34:09 +0200
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <h40adj$bv6$1@adenine.netfront.net>
References: <mailman.3406.1248034495.8015.python-list@python.org>
	<h40adj$bv6$1@adenine.netfront.net>
Message-ID: <4A643A11.6030109@gmail.com>

thanks Marcus,

Marcus Wanner wrote:
> On 7/19/2009 4:15 PM, Stef Mientki wrote:
>> hello,
>>
>> I'm using Scintilla as a wxPython widget with great pleasure.
>> I now have an application where I want to make notes during a 
>> conversation,
>> but also want to record the speech during that conversation.
>> I'm using Scintilla as a wxPython widget for editing and PyAudio for 
>> the speech recording,
>> until so far everything works fine.
>>
>> Here the problem part:
>> I need to synchronize the typed text with the sound during playback.
>> So if I click somewhere in the sound recording,
>> the line of text, typed that moment should be highlighted.
>> And vise versa, if the cursor in the text is moved and some special 
>> key is pressed,
>> the sound starting 10 or 20seconds earlier should be playbacked.
>>
>> I though of adding bookmarks (because these are fixed in the text), 
>> and keep a list of bookmarks and sound pointers.
>> This idea should work, but there are only 31 bookmarks.
>>
>> Any other suggestions ?
>>
>> thanks,
>> Stef Mientki
> That sounds like a very specialized type of thing, 
Well from an application point of view,
with the current netbooks,
this looks like a perfect tool for any conversation or meeting.
> which only the few people with experience with wxPython, PyAudio, and 
> Scintilla could help you with...
>
I was afraid of that too, so I dropped the question in several places,
and the writer of Scintilla himself came with the perfect answer.

cheers,Stef
> But you might try having a dictionary with notes and associated times, 
> or just give each note a four-digit ID number at the beginning of it 
> when it's entered and use that in the dictionary (to keep keys 
> shorter). Or you could just do a little hack and increase the number 
> of bookmarks allowed (seeing as source is available) :p
>
> Marcus



From sion at viridian.paintbox  Mon Jul 20 05:34:24 2009
From: sion at viridian.paintbox (Sion Arrowsmith)
Date: Mon, 20 Jul 2009 09:34:24 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
	<mailman.3317.1247864411.8015.python-list@python.org>
Message-ID: <ASW8m.3332$Tk2.91@newsfe21.ams2>

Terry Reedy  <tjreedy at udel.edu> wrote:
>Sion Arrowsmith wrote:
>> Jack Diederich  <jackdied at gmail.com> wrote:
>>> It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>>> dicts also raise an error if you try to LT them.
>> Python 2.5.2
>>>>> d1 = dict((str(i), i) for i in range (10))
>>>>> d2 = dict((str(i), i) for i in range (20))
>>>>> d1 < d2
>> True
>Try reversing the definitions of d1 and d2. The dicts are probably being 
>compared by id (address), which is the 2.x CPython default.

Like this?

>>> d1 = dict((str(i), i) for i in range (20))
>>> d2 = dict((str(i), i) for i in range (10))
>>> d1 < d2
False
>>> id(d1) < id(d2)
True

I didn't know that comparison for anything other than equality
defaulted to using id. That really is rather broken, and I'm
glad 3.0 fixed it.

-- 
\S

   under construction



From walkraft at gmail.com  Mon Jul 20 05:57:36 2009
From: walkraft at gmail.com (casebash)
Date: Mon, 20 Jul 2009 02:57:36 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
Message-ID: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>

Hi,

I have searched this list and found out that Python doesn't have a
mutable string class (it had an inefficient one, but this was removed
in 3.0). Are there any libraries outside the core that offer this?

Thanks,

Chris


From vivainio at gmail.com  Mon Jul 20 06:12:25 2009
From: vivainio at gmail.com (Ville Vainio)
Date: Mon, 20 Jul 2009 03:12:25 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() that 
	doesn't block gui event loops
Message-ID: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>

Has anyone implementing something like what the subject line
indicates?

The idea:

To run functions that execute a series of system commands without
blocking the ui, *and* without adding state machine logic.

The syntax would be something like:

def work():

  showstatus("building")
  r = yield runshell("make")
  showstatus("installing")
  r = yield runshell("make install")
  showstatus("Success")

mygui.startwork(work)
# returns immediately, runs work() gradually in the background.


The catch is that showstatus() would need to be run in the mainloop,
so running the whole thing in a thread is a no-go.

I imagine runshell() would be implemented in terms of QProcess, or
subprocess.Popen/os.system and a worker thread.

Anyone done this already, or do I have to roll my own?


From vivainio at gmail.com  Mon Jul 20 06:14:35 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Mon, 20 Jul 2009 03:14:35 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <9600897a-100c-4907-826d-0d700cef6880@r2g2000yqm.googlegroups.com>

On Jul 20, 1:12?pm, Ville Vainio <vivai... at gmail.com> wrote:

> Has anyone implementing something like what the subject line

ImplentED.

I don't think this is that hard to do in the first place, but a
"generic" solution that can be easily tuned for different gui
mainloops would be nice.


From pavlovevidence at gmail.com  Mon Jul 20 06:26:09 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 20 Jul 2009 03:26:09 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <cb66436c-0748-4804-94a6-feb846093d06@v37g2000prg.googlegroups.com>

On Jul 20, 2:57?am, casebash <walkr... at gmail.com> wrote:
> Hi,
>
> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

I just did a brief search on Python Packaging Index (pypi.python.org)
and saw nothing.  You might have better luck.

I suspect there is not a mutable string class partly because there is
little demand, partly because it'd be hard to make an object that is
usable everywhere a string is.  For instance, a third-party string
object might not work with the re module.

The core does have some classes that are kind of like strings but
mutable.  The array module can create mutable arrays of characters
which are somewhat like strings.  Depending on your use case some
other things might suffice (such as mmap,  io.StringIO, or even a list
of characters).


Carl Banks


From vivainio at gmail.com  Mon Jul 20 06:28:33 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Mon, 20 Jul 2009 03:28:33 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <ffdab149-c5bb-404b-8a8b-eaf1fb4fe91c@w41g2000yqb.googlegroups.com>

On Jul 20, 1:12?pm, Ville Vainio <vivai... at gmail.com> wrote:

> I imagine runshell() would be implemented in terms of QProcess, or
> subprocess.Popen/os.system and a worker thread.

Actually, the problem is that of general serialization of worker
thread operations. That is, it could be something akin to:

res = yield run_in_thread(lambda : os.system('make'))

run_in_thread would basically grab a worked thread, execute the
callable, and allow the generator to proceed after the thread is done.
Now, the only thing to do is the "generator dispatcher" in gui
mainloop that finds the correct generator and makes it proceed...


From ben+python at benfinney.id.au  Mon Jul 20 07:08:22 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Mon, 20 Jul 2009 21:08:22 +1000
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <87r5wba9y1.fsf@benfinney.id.au>

casebash <walkraft at gmail.com> writes:

> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

A mutable string would not (AFAICT) be usefully implementable as a
subclass of the built-in string types. So even if such a type existed,
it would not be useable with all the functionality that works with
strings.

What is it you're trying to do that makes you search for a mutable
string type? It's likely that a better approach can be found.

-- 
 \     ?As scarce as truth is, the supply has always been in excess of |
  `\                                       the demand.? ?Josh Billings |
_o__)                                                                  |
Ben Finney


From sjmachin at lexicon.net  Mon Jul 20 07:24:06 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 04:24:06 -0700 (PDT)
Subject: On out-of-date Python Applications
References: <mailman.3387.1247990649.8015.python-list@python.org> 
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com> 
	<4A632C9D.2010303@it.uu.se>
	<mailman.3397.1248018457.8015.python-list@python.org>
Message-ID: <e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>

On Jul 20, 1:47?am, John Machin <sjmac... at lexicon.net> wrote:
> On 20/07/2009 12:24 AM, Virgil Stokes wrote:
> > John Machin wrote:
> >> On Jul 19, 6:04 pm, Virgil Stokes <v... at it.uu.se> wrote:
> >>> I am not a heavy user of Python; but, I do work with it and some of its
> >>> application packages (e.g. PyODE), in an academic setting.
> >>> Many of these applications packages have a Windows installer which
> >>> usually works fine. However, I also try to keep up with the latest
> >>> release of Python, and this is where I often have problems. That is, the
> >>> latest Windows installer provided for some of these applications will
> >>> not install on the latest version of Python.
> > Actually John,
> > My question was about the more general case --- how to help with
> > upgrading applications; but, I will try to address your email.
> >> Otherwise: What does "will not install" mean?
> > This means that when the Windows installer is executed it informs you
> > that you do not have a match between the application and the Python that
> > it finds on your Windows PC. You can easily find this out for yourself
> > by trying to install PyODE on a Windows platform with a Python version
> > later than 2.5.x.
> >> Are these pure Python
> >> packages or do they include C extensions (binary (pyd) or source?)?
> > Obviously, this depends on the application. In the particular case that
> > I mentioned (PyODE) I believe that there is a mix of C binaries and
> > Python code.
> >> At
> >> what stage of the installation does the installation fail?
> > In the initial stages.
> >> With what
> >> error message(s)?
> > In one specific case, the message is (paraphrasing) "You do not have
> > Python 2.5 installed" --- the installation is then aborted.
> >> With what versions of Python?
>
> > I have only Python 2.6.2 on my home Windows Vista PC and PyODE does not
> > have a Windows Installer for Python 2.6.
>
> >>> I do understand that there can be a time lag between the release of
> >>> Python applications and the latest Python. I also appreciate the work of
> >>> the people that are responsible for these applications.
>
> >>> My question is --- Is there anything I, as a user of an application
> >>> package that is out-of-date with respect to the latest Python, can do to
> >>> help in this process of bringing an application ?up-to-date?
> > Note, again John, my question was about how I might assist (help) with
> > the updating of applications;
>
> Your answers have been very helpful in determining exactly what your
> problem is; thank you.
>
> > but, thank you for your interest in this.
> > Perhaps, only the owner/responsible programmer for the application can
> > create a Windows installer,
>
> Given a source distribution, a suitable C++ compiler, and the suspension
> of Murphy's Law, anyone should be able to (a) install it on their own
> machine (b) make a Windows installer.
>
> > or perhaps others could assist with this ---
>
> Perhaps indeed ...
>
> > this is what my question was about. I would be glad to assist if
> > possible :-)
>
> Suggestions:
>
> (1) contact the pyODE maintainer and ask, or check out the project's
> forums on sourceforge
>
> (2) if you have a C++ compiler on your Windows box: get the source
> distribution, unpack it, ensure that the ODE_BASE in the setup.py points
> to your (existing) ODE 0.7 installation, do
> ? ? ?\python26\python setup.py install
> and stand well back.
>
> I have just tried this and got a ton of warnings from the compile and 3
> errors from the link:
>
> build\lib.win32-2.6\ode.pyd : fatal error LNK1120: 3 unresolved externals
> error: command '"C:\Program Files\Microsoft Visual Studio
> 9.0\VC\BIN\link.exe"' failed with exit status 1120

Update: The problem is evidently with the lib(s) available with ODE
0.7 (or 0.8 -- there are conflicting stories about which one to use
with PyODE); they were compiled with VS2003 AFAICT and the complained-
of symbols are not supplied by VS2009 which is what I'm using to try
and build PyODE for Python 2.6 .

The next step would be to try to compile ODE 0.7 or 0.8 with VS9 --
however this would require "project files" for ODE for VS9, and there
aren't any on the ODE website; it has only those for VS3 and VS5.

As all I know about VS9 is that somewhere inside the ferschlugginer
100 Mb download there's a C compiler that does the right thing when
distutils pushes its button, I'm going to have to punt this back to
you to follow up on suggestion (1) ... skip asking the pyODE
maintainer (last heard saying little time available and he wasn't
even /using/ pyODE any more); try asking on the pyODE and ODE mailing-
lists has anyone contemplated a Python 2.6 / win32 / VS 2009 build of
pyODE.

Cheers,
John


From sjmachin at lexicon.net  Mon Jul 20 07:30:12 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 04:30:12 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
Message-ID: <47ab4ab6-d8c8-4997-8963-ac41b00dd10f@y10g2000prg.googlegroups.com>

On Jul 20, 9:08?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> casebash <walkr... at gmail.com> writes:
> > I have searched this list and found out that Python doesn't have a
> > mutable string class (it had an inefficient one, but this was removed
> > in 3.0). Are there any libraries outside the core that offer this?
>
> A mutable string would not (AFAICT) be usefully implementable as a
> subclass of the built-in string types. So even if such a type existed,
> it would not be useable with all the functionality that works with
> strings.
>
> What is it you're trying to do that makes you search for a mutable
> string type? It's likely that a better approach can be found.
>

OK, I'll bite: where does the Python 3.x bytearray type fit into your
taxonomy? At first glance it appears to be mutable and have a fair
swag of functionality.


From drobinow at gmail.com  Mon Jul 20 07:46:12 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 20 Jul 2009 07:46:12 -0400
Subject: On out-of-date Python Applications
In-Reply-To: <e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
References: <mailman.3387.1247990649.8015.python-list@python.org>
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>
	<4A632C9D.2010303@it.uu.se>
	<mailman.3397.1248018457.8015.python-list@python.org>
	<e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
Message-ID: <4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>

On Mon, Jul 20, 2009 at 7:24 AM, John Machin<sjmachin at lexicon.net> wrote:
...
> The next step would be to try to compile ODE 0.7 or 0.8 with VS9 --
> however this would require "project files" for ODE for VS9, and there
> aren't any on the ODE website; it has only those for VS3 and VS5.
>
 The ODE site is a mess.
Go to http://www.ode.org/svn.html  and click on:   Instructions for
accessing the repository
 Scroll down to the section "Building with Premake"
 (Note that there is no directory "ode/build" -- you want the "build"
directory, which contains premake4.exe)
I used "premake4 --with-demos --with-tests vs2008"
I have successfully compiled ode-0.11.1 using these instructions. I
have not yet run the tests or demos or tried to compile PyODE.


From wilk at flibuste.net  Mon Jul 20 07:56:49 2009
From: wilk at flibuste.net (William Dode)
Date: 20 Jul 2009 11:56:49 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
Message-ID: <4a645b81$0$12974$426a74cc@news.free.fr>

On 19-07-2009, Mark Dufour wrote:
> Hi all,
>
> I have just released version 0.2 of Shed Skin, an experimental
> (restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).

I just tested it with a litle game, to find the places of horse on 
a board 5x5. The result is :

c 5s
gcj 7s
java 7s
shedskin 8s
python + psyco 18s
cython avec malloc *int 18s
cython 55s avec [] python
python 303s (5m3s)

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From Lacrima.Maxim at gmail.com  Mon Jul 20 08:20:26 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Mon, 20 Jul 2009 05:20:26 -0700 (PDT)
Subject: Design question.
Message-ID: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>

Hello!

I am newbie in python and I have really simple question, but I need
your advice to know how to do best.
I need to store a number of dictionaries in certain place. I've
decided to store them in a separate module.
Like this:
dicts.py
-----------------------
dict1 = {....}
dict2 = {....}
dict3 = {....}

Then, when I need any dictionary, I can access it:
import dicts
dicts.dict1

Is it a good practice? Or should I store them as class attributes or
anything else?

Thanks in advance.

With regards, Max
(sorry if my English isn't very proper)


From magobin at gmail.com  Mon Jul 20 08:28:27 2009
From: magobin at gmail.com (Alex)
Date: Mon, 20 Jul 2009 05:28:27 -0700 (PDT)
Subject: A lot of problem with pygame.mixer module!
Message-ID: <a06c2c1c-7727-46d4-8876-55ffe9543493@d4g2000yqa.googlegroups.com>

hi at all,
As email object I 'm not be able to run my program when compiled with
py2exe.
Everythink  works fine until I try to make an exe.
After that, it crash and in the log:

C:\dist\sponge.exe:97: RuntimeWarning: use mixer: DLL load failed: The
specified module could not be found.
Traceback (most recent call last):
  File "sponge.py", line 97, in <module>
  File "pygame\__init__.pyo", line 70, in __getattr__
NotImplementedError: mixer module not available

The code about pygame.mixer is only:

pygame.mixer.init()
music = pygame.mixer.Sound("popcorn.ogg")
music.play()

in the dist folder there is SDL_mixer.dll so...HOW can I solve this
problem ??
thanks in advance
Alex
Below my setup.py

# py2exe setup program
from distutils.core import setup
import py2exe
import pygame
from modulefinder import Module
#from pygame import mixer
import ImageGrab
import sys
import os
import Tkinter
import glob, shutil
sys.argv.append("py2exe")

VERSION = '1.0'
AUTHOR_NAME = 'Your Name'
AUTHOR_EMAIL = 'your_email at somewhere.com'
AUTHOR_URL = "http://www.urlofyourgamesite.com/"
PRODUCT_NAME = "Sponge"
SCRIPT_MAIN = 'sponge.py'
VERSIONSTRING = PRODUCT_NAME + " ALPHA " + VERSION
ICONFILE = 'icon.ico'

# Remove the build tree on exit automatically
REMOVE_BUILD_ON_EXIT = True

if os.path.exists('dist/'): shutil.rmtree('dist/')

extra_files = [ ("",[ICONFILE,'WinLockDll.dll','popcorn.ogg']),
                   #("data",glob.glob(os.path.join('data','*.dat'))),
                   #("gfx",glob.glob(os.path.join('gfx','*.jpg'))),
                   #("gfx",glob.glob(os.path.join('gfx','*.png'))),
                   ("fonts",glob.glob(os.path.join('fonts','*.ttf'))),
                   ("music",glob.glob(os.path.join('music','*.ogg')))]
                   #("snd",glob.glob(os.path.join('snd','*.wav')))]

# List of all modules to automatically exclude from distribution build
# This gets rid of extra modules that aren't necessary for proper
functioning of app
# You should only put things in this list if you know exactly what you
DON'T need
# This has the benefit of drastically reducing the size of your dist

MODULE_EXCLUDES =[
'email',
'AppKit',
'Foundation',
'bdb',
'difflib',
'tcl',
#'Tkinter',
#'Tkconstants',
'curses',
'distutils',
'setuptools',
'urllib',
'urllib2',
'urlparse',
'BaseHTTPServer',
'_LWPCookieJar',
'_MozillaCookieJar',
'ftplib',
'gopherlib',
'_ssl',
'htmllib',
'httplib',
'mimetools',
'mimetypes',
'rfc822',
'tty',
'webbrowser',
'socket',
'hashlib',
#'base64',
'compiler',
'pydoc'
]

INCLUDE_STUFF = ['encodings',"encodings.latin_1"]

setup(windows=[
             {'script': SCRIPT_MAIN,
               'other_resources': [(u"VERSIONTAG",1,VERSIONSTRING)],
               'icon_resources': [(1,ICONFILE)]}],
         options = {"py2exe": {
                             "optimize": 2,
                             "includes": INCLUDE_STUFF,
                             "compressed": 1,
                             "ascii": 1,
                             #"bundle_files": 1,
                             "ignores":
['tcl','AppKit','Numeric','Foundation'],
                             "excludes": MODULE_EXCLUDES} },
          name = PRODUCT_NAME,
          version = VERSION,
          data_files = extra_files,
          #zipfile = None,
          author = AUTHOR_NAME,
          author_email = AUTHOR_EMAIL,
          url = AUTHOR_URL)

# Create the /save folder for inclusion with the installer
#shutil.copytree('save','dist/save')

#if os.path.exists('dist/tcl'): shutil.rmtree('dist/tcl')

# Remove the build tree
if REMOVE_BUILD_ON_EXIT:
     shutil.rmtree('build/')

if os.path.exists('dist/tcl84.dll'): os.unlink('dist/tcl84.dll')
if os.path.exists('dist/tk84.dll'): os.unlink('dist/tk84.dll')


From vippstar at gmail.com  Mon Jul 20 08:29:40 2009
From: vippstar at gmail.com (vippstar)
Date: Mon, 20 Jul 2009 05:29:40 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
Message-ID: <fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>

On Jul 20, 9:13?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Steven D'Aprano <ste... at REMOVE.THIS.cybersource.com.au> writes:
> > Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing
> > to do. It's the right thing to do if you're doing integer maths.
>
> I wonder whether 2/3 => ValueError is preferable.

Not all software wants this. It shouldn't be part of the language but
rather part of your code if you need such a feature. (for instance, to
distinguish between 2/3 and divisions with 0 dividend).


From deets at nospam.web.de  Mon Jul 20 08:31:15 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 20 Jul 2009 14:31:15 +0200
Subject: Design question.
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
Message-ID: <7cj63mF285spnU1@mid.uni-berlin.de>

Lacrima wrote:

> Hello!
> 
> I am newbie in python and I have really simple question, but I need
> your advice to know how to do best.
> I need to store a number of dictionaries in certain place. I've
> decided to store them in a separate module.
> Like this:
> dicts.py
> -----------------------
> dict1 = {....}
> dict2 = {....}
> dict3 = {....}
> 
> Then, when I need any dictionary, I can access it:
> import dicts
> dicts.dict1
> 
> Is it a good practice? Or should I store them as class attributes or
> anything else?

It's perfectly fine to use dictionaries as module-level objects for storing
e.g. configuration-data.

OTOH it's also fine to do so as class-attributes. Choosing one over the
other has a lot to do with the actual problem you are working on. 


Diez


From ndbecker2 at gmail.com  Mon Jul 20 08:39:28 2009
From: ndbecker2 at gmail.com (Neal Becker)
Date: Mon, 20 Jul 2009 08:39:28 -0400
Subject: proposal: add setresuid() system call to python
References: <20090717200141.GI6065@subspacefield.org>
	<148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>
Message-ID: <h41oi0$v1$1@ger.gmane.org>

Mahmoud Abdelkader wrote:

> Why don't you write a python extension module? This is a perfect
> opportunity for that.
> 
I think having a module just for one system call is a bit silly.  Why not 
add to os module?




From miheavner at gmail.com  Mon Jul 20 08:41:02 2009
From: miheavner at gmail.com (mheavner)
Date: Mon, 20 Jul 2009 05:41:02 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
	<m2iqhru34c.fsf@cs.uu.nl>
Message-ID: <b893725d-4dea-4b16-90c5-d1e34e374b1b@h31g2000yqd.googlegroups.com>

Piet,

The situation is 1a of your listed options, however my issue was
solved. I was stopping the subprocesses from consuming more data at
each iteration which led to the data being lost since the subprocess
worker function would then end - I now keep them alive across
iterations.

Thanks for your help, I'm new to the multiprocessing module and this
was very helpful!

On Jul 17, 4:26?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> There is stil something not clear in your description.
>
> >m> I'm using multiprocessing to spawn several subprocesses, each of which
> >m> uses a very large data structure (making it impractical to pass it via
> >m> pipes / pickling). I need to allocate this structure once when the
> >m> process is created and have it remain in memory for the duration of
> >m> the process.
>
> I have read this as that every subprocess has its own large
> data structure and that there is no connection between these.
>
> But seeing where the discussion is going I guess there might be
> different interpretations. So can you enlighten us how the situation is?
>
> 1. Each subprocess has a copy of a data structure that is prepared by the
> ? ?master process. Therefore you want it to be passed by the fork
> ? ?1a. the data structure is constant i.e. the subprocess doesn't change it
> ? ?1b. the subprocess makes changes in its copy
> 2. Each subprocess has a seperate data structure not equal to the others
> 3. Something else.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org



From Lacrima.Maxim at gmail.com  Mon Jul 20 08:44:22 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Mon, 20 Jul 2009 05:44:22 -0700 (PDT)
Subject: Design question.
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
	<7cj63mF285spnU1@mid.uni-berlin.de>
Message-ID: <825d0aae-3147-4f81-8c82-fa86e4b777df@c29g2000yqd.googlegroups.com>

On Jul 20, 3:31?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Lacrima wrote:
> > Hello!
>
> > I am newbie in python and I have really simple question, but I need
> > your advice to know how to do best.
> > I need to store a number of dictionaries in certain place. I've
> > decided to store them in a separate module.
> > Like this:
> > dicts.py
> > -----------------------
> > dict1 = {....}
> > dict2 = {....}
> > dict3 = {....}
>
> > Then, when I need any dictionary, I can access it:
> > import dicts
> > dicts.dict1
>
> > Is it a good practice? Or should I store them as class attributes or
> > anything else?
>
> It's perfectly fine to use dictionaries as module-level objects for storing
> e.g. configuration-data.
>
> OTOH it's also fine to do so as class-attributes. Choosing one over the
> other has a lot to do with the actual problem you are working on.
>
> Diez

Hi!

Thank you very much for your so soon reply!

With regards,
Max


From jeanmichel at sequans.com  Mon Jul 20 09:05:13 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 20 Jul 2009 15:05:13 +0200
Subject: Design question.
In-Reply-To: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
Message-ID: <4A646B89.7060103@sequans.com>

Lacrima wrote:
> Hello!
>
> I am newbie in python and I have really simple question, but I need
> your advice to know how to do best.
> I need to store a number of dictionaries in certain place. I've
> decided to store them in a separate module.
> Like this:
> dicts.py
> -----------------------
> dict1 = {....}
> dict2 = {....}
> dict3 = {....}
>
> Then, when I need any dictionary, I can access it:
> import dicts
> dicts.dict1
>
> Is it a good practice? Or should I store them as class attributes or
> anything else?
>
> Thanks in advance.
>
> With regards, Max
> (sorry if my English isn't very proper)
>   
Defining dict as a module attribute ic correct, but try to answer the 
following question:

Is dict1 an attribute/property/declension of the object/entity defined 
by the module dicts ?
If yes, then your design is correct.

An correct example:
fruits.py
------------
apple = {}
banana = {}

An incorrect one:
fruit.py
-----------
apple={}
bicycle={}

Basically, the rule is very straightforward, set your dict as a module 
attribute only if its one of its attribute (very nice paraphrase !)
Most of people (including me) tend to have a  module, where they put 
everything they have no idea about their location. This is a bad habit 
and result from a uncontrolled/undocumented design. Usually documenting 
objects in such modules is really painful.

Your proposal is fine from a python syntax point of view. I can't tell 
of your design with names like (dicts.py and dict1,dict2) hoping you do 
not intend to name them that way.

JM


From deets at nospam.web.de  Mon Jul 20 09:10:17 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 20 Jul 2009 15:10:17 +0200
Subject: proposal: add setresuid() system call to python
References: <20090717200141.GI6065@subspacefield.org>
	<148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>
	<mailman.3421.1248093585.8015.python-list@python.org>
Message-ID: <7cj89qF27mfrjU1@mid.uni-berlin.de>

Neal Becker wrote:


again with his notorious gmane.comp.python.general group that doesn't work
for any decent news-reader.....


> Mahmoud Abdelkader wrote:
> 
>> Why don't you write a python extension module? This is a perfect
>> opportunity for that.
>> 
> I think having a module just for one system call is a bit silly.  Why not
> add to os module?

While I do agree that it's an omission, it is easy enough to get it yourself
using ctypes:


from ctypes import *
from ctypes.util import find_library

clib = CDLL(find_library("c"))
# this might be different on 64bit
__uid_t = c_uint

_setresuid = clib.setresuid
_setresuid.argtypes = [__uid_t, __uid_t, __uid_t]
_setresuid.restype = c_int

def setresuid(ruid, euid, suid):
    return _setresuid(__uid_t(ruid), __uid_t(euid), __uid_t(suid))


print setresuid(1000, 1000, 1000) # returns 0 for me
print setresuid(1001, 1001, 1001) # fails.

Diez


From stefan_ml at behnel.de  Mon Jul 20 09:22:02 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Mon, 20 Jul 2009 15:22:02 +0200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <4a645b81$0$12974$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <4a646f7b$0$31869$9b4e6d93@newsspool3.arcor-online.net>

William Dode wrote:
> On 19-07-2009, Mark Dufour wrote:
>> I have just released version 0.2 of Shed Skin, an experimental
>> (restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).
> 
> I just tested it with a litle game, to find the places of horse on 
> a board 5x5. The result is :
>
> [...]
> shedskin 8s
> python + psyco 18s
> cython avec malloc *int 18s
> cython 55s avec [] python
> python 303s (5m3s)

Note that both Psyco and Cython make a lot less assumptions about Python
code than Shed Skin does. Psyco has the advantage of just needing to jump
in when it finds out that it can help, so it's the most broadly compatible
of the three. But Cython also supports quite a large corpus of dynamic
Python code by now. Shed Skin has a lot of restrictions, many of which are
by design. It's not intended to compile dynamic code, and I think that's a
good thing, because that's what makes it fast for the code that it
supports. Getting the same speed in Cython requires a bit more explicit
typing, simply because Cython does not assume these restrictions.

I think that all three have their raison d'?tre, and it currently looks
like all three are there to stay and to keep growing better. And I'm also
happy to read that some optimisations jump from one to the other. ;)

Stefan


From Lacrima.Maxim at gmail.com  Mon Jul 20 09:42:23 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Mon, 20 Jul 2009 06:42:23 -0700 (PDT)
Subject: Design question.
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
	<mailman.3423.1248095131.8015.python-list@python.org>
Message-ID: <68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>

On Jul 20, 4:05?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> Lacrima wrote:
> > Hello!
>
> > I am newbie in python and I have really simple question, but I need
> > your advice to know how to do best.
> > I need to store a number of dictionaries in certain place. I've
> > decided to store them in a separate module.
> > Like this:
> > dicts.py
> > -----------------------
> > dict1 = {....}
> > dict2 = {....}
> > dict3 = {....}
>
> > Then, when I need any dictionary, I can access it:
> > import dicts
> > dicts.dict1
>
> > Is it a good practice? Or should I store them as class attributes or
> > anything else?
>
> > Thanks in advance.
>
> > With regards, Max
> > (sorry if my English isn't very proper)
>
> Defining dict as a module attribute ic correct, but try to answer the
> following question:
>
> Is dict1 an attribute/property/declension of the object/entity defined
> by the module dicts ?
> If yes, then your design is correct.
>
> An correct example:
> fruits.py
> ------------
> apple = {}
> banana = {}
>
> An incorrect one:
> fruit.py
> -----------
> apple={}
> bicycle={}
>
> Basically, the rule is very straightforward, set your dict as a module
> attribute only if its one of its attribute (very nice paraphrase !)
> Most of people (including me) tend to have a ?module, where they put
> everything they have no idea about their location. This is a bad habit
> and result from a uncontrolled/undocumented design. Usually documenting
> objects in such modules is really painful.
>
> Your proposal is fine from a python syntax point of view. I can't tell
> of your design with names like (dicts.py and dict1,dict2) hoping you do
> not intend to name them that way.
>
> JM

Hi, Jean-Michel!

Thanks for your answer.
I am not going to have names like dicts.py and dict1,dict2. That was
just example. I wanted to know if it is correct to have dictionaries
on a module level. Now I know that this is correct. I want to collect
in one module a number of dictionaries, every of which describes a
separate web service. And my function in another module will import
required dictionary, depending on what web service should be used.
Thanks again for the help.

With regards,
Max.
(sorry if my English isn't very proper)


From gerard.blais at gmail.com  Mon Jul 20 09:47:54 2009
From: gerard.blais at gmail.com (Gerry)
Date: Mon, 20 Jul 2009 06:47:54 -0700 (PDT)
Subject: win32api install problem
Message-ID: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>

I'm running Python 2.6 under XP.

I've installed Windows 32 extensions for Python 2.6 version 1.4
(pywin32-214.win32-py2.6.exe).

But If I try to import win32api, I get:

  File "C:\python_projects\euler\driveletters.py", line 1, in <module>
    import win32api
ImportError: DLL load failed: The specified module could not be found.

\Python26\Lib\site-packages has:

03/23/2009  08:35 AM    <DIR>          win32
07/20/2009  09:08 AM    <DIR>          win32com
02/18/2009  01:21 PM    <DIR>          win32comext

Can anyone offer a suggestion?

Thanks,

Gerry




From mail at timgolden.me.uk  Mon Jul 20 09:57:56 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 20 Jul 2009 14:57:56 +0100
Subject: win32api install problem
In-Reply-To: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
Message-ID: <4A6477E4.3030808@timgolden.me.uk>

Gerry wrote:
> I'm running Python 2.6 under XP.
> 
> I've installed Windows 32 extensions for Python 2.6 version 1.4
> (pywin32-214.win32-py2.6.exe).
> 
> But If I try to import win32api, I get:
> 
>   File "C:\python_projects\euler\driveletters.py", line 1, in <module>
>     import win32api
> ImportError: DLL load failed: The specified module could not be found.

Used to be you'd get this error if you installed as a
non-admin user. Don't know if that's still an issue.
Possibility?

TJG


From dtgeadamo at yahoo.com  Mon Jul 20 09:57:57 2009
From: dtgeadamo at yahoo.com (mistersexy)
Date: Mon, 20 Jul 2009 06:57:57 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService 
	Account
Message-ID: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>

I am trying to create a Windows service in Python using pywin32. I do
not want this service to run under a user account. I want this service
to be able to run as a LocalService, NetworkService and the like. How
do I specify this using the win32 library? Thanks, everyone.


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 20 10:00:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 20 Jul 2009 14:00:30 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
	<mailman.3317.1247864411.8015.python-list@python.org>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
Message-ID: <02746997$0$5185$c3e8da3@news.astraweb.com>

On Mon, 20 Jul 2009 09:34:24 +0000, Sion Arrowsmith wrote:

> Terry Reedy  <tjreedy at udel.edu> wrote:
>>Sion Arrowsmith wrote:
>>> Jack Diederich  <jackdied at gmail.com> wrote:
>>>> It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>>>> dicts also raise an error if you try to LT them.
>>> Python 2.5.2
>>>>>> d1 = dict((str(i), i) for i in range (10)) d2 = dict((str(i), i)
>>>>>> for i in range (20)) d1 < d2
>>> True
>>Try reversing the definitions of d1 and d2. The dicts are probably being
>>compared by id (address), which is the 2.x CPython default.
> 
> Like this?
> 
>>>> d1 = dict((str(i), i) for i in range (20)) 
>>>> d2 = dict((str(i), i) for i in range (10))
>>>> d1 < d2
> False
>>>> id(d1) < id(d2)
> True
> 
> I didn't know that comparison for anything other than equality defaulted
> to using id. That really is rather broken, and I'm glad 3.0 fixed it.


I don't think comparisons other than equality use id. That would be 
rather insane. If anyone can demonstrate such comparisons in a built-in 
or standard library class, I'd like to see it.


For the record, dicts have been comparable with < and > since at least 
Python 1.5:

$ python1.5
Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
4.1.2-27)] on linux2
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>
>>> {1: 'a', 2: 'b'} < {2: 'b', 3: 'a'}
1


Reading the docs:

http://docs.python.org/library/stdtypes.html#comparisons
http://docs.python.org/library/stdtypes.html#mapping-types-dict

I can only suggest that dicts compare in an arbitrary but consistent 
fashion. What that is based on, I don't know, but based on some very 
limited testing, I'd guess it is like this:

If the two dicts have unequal length, the longer dict compares greater 
than the shorter dict.

If the two dicts are equal in length, (key, item) pairs are compared, 
probably in lexicographic order, because the order of insertion of keys 
doesn't appear to matter.


-- 
Steven


From mail at timgolden.me.uk  Mon Jul 20 10:03:14 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 20 Jul 2009 15:03:14 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
Message-ID: <4A647922.4080908@timgolden.me.uk>

mistersexy wrote:
> I am trying to create a Windows service in Python using pywin32. I do
> not want this service to run under a user account. I want this service
> to be able to run as a LocalService, NetworkService and the like. How
> do I specify this using the win32 library? Thanks, everyone.

When you "install" the service, using the HandleCommandLine
option, specify --username= and --password options.

TJG


From nyamatongwe+thunder at gmail.com  Mon Jul 20 10:05:33 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Mon, 20 Jul 2009 14:05:33 GMT
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>

casebash:

> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

   I wrote a gap buffer implementation for Python 2.5 allowing
character, unicode character and integer elements.

http://code.google.com/p/gapbuffer/

   Its not seen much use or any maintenance so is unlikely to work with
Python 3.x.

   Neil


From hniksic at xemacs.org  Mon Jul 20 10:10:35 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Mon, 20 Jul 2009 16:10:35 +0200
Subject: proposal: add setresuid() system call to python
References: <20090717200141.GI6065@subspacefield.org>
	<148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>
	<mailman.3421.1248093585.8015.python-list@python.org>
	<7cj89qF27mfrjU1@mid.uni-berlin.de>
Message-ID: <877hy38mxw.fsf@busola.homelinux.net>

"Diez B. Roggisch" <deets at nospam.web.de> writes:

To emulate the os-module-type calls, it's better to raise exceptions
than return negative values:

> def setresuid(ruid, euid, suid):
>     return _setresuid(__uid_t(ruid), __uid_t(euid), __uid_t(suid))

def setresuid(ruid, euid, suid):
    res = _setresuid(__uid_t(ruid), __uid_t(euid), __uid_t(suid))
    if res < 0:
        raise OSError('[Errno %d] %s' % (os.errno, errno.strerror(os.errno)))


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 20 10:21:15 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 20 Jul 2009 14:21:15 GMT
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
Message-ID: <02746e73$0$5185$c3e8da3@news.astraweb.com>

On Mon, 20 Jul 2009 21:08:22 +1000, Ben Finney wrote:

> casebash <walkraft at gmail.com> writes:
> 
>> I have searched this list and found out that Python doesn't have a
>> mutable string class (it had an inefficient one, but this was removed
>> in 3.0). Are there any libraries outside the core that offer this?
> 
> A mutable string would not (AFAICT) be usefully implementable as a
> subclass of the built-in string types. So even if such a type existed,
> it would not be useable with all the functionality that works with
> strings.

If applications ignore duck-typing and do isinstance(value, str), it's 
arguably the application and not the value that is broken.

Besides, with the new __isinstance__ method, surely such a mutable string 
could claim to be an instance of string without needing to inherit from 
string?


> What is it you're trying to do that makes you search for a mutable
> string type? It's likely that a better approach can be found.

When dealing with very large strings, it is wasteful to have to duplicate 
the entire string just to mutate a single character.

However, when dealing with very large strings, it's arguably better to 
use the rope data structure instead.


http://en.wikipedia.org/wiki/Rope_(computer_science)



-- 
Steven


From invalid at invalid  Mon Jul 20 10:59:17 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 20 Jul 2009 09:59:17 -0500
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
	<1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
	<jabdj6-qij.ln1@ozzie.tundraware.com>
Message-ID: <G_KdnezoObjYG_nXnZ2dnUVZ_vKdnZ2d@posted.visi>

On 2009-07-20, Tim Daneliuk <tundra at tundraware.com> wrote:

>>> In fact, picking a computer language is the most important
>>> discussion in Computer Science and eclipses even P=NP? in
>>> significance. I sure hope we can keep this thread going for a
>>> few months.
>> 
>> Please feel free to extend this flame-war along for a few
>> months on comp.lang.lisp.  Not here.
>
> Uh Carl ... are you familiar with the concept of mocking humor?

Irony on Usenet: always a bit of a gamble...

-- 
Grant Edwards                   grante             Yow! Vote for ME -- I'm
                                  at               well-tapered, half-cocked,
                               visi.com            ill-conceived and
                                                   TAX-DEFERRED!


From craig1.boyd at citi.com  Mon Jul 20 11:09:47 2009
From: craig1.boyd at citi.com (Boyd, Craig1 )
Date: Mon, 20 Jul 2009 10:09:47 -0500
Subject: Auto-generate GUI from a database table structure
Message-ID: <55660F9659966544BBA3AE14CE5D278D01243B8E04@exgtmb08.nam.nsroot.net>

Hello All,

I am REALLY new to python and still trying to figure a lot of this stuff out.
I am trying to write a couple screens to update three or four database tables on Oracle 10g and I was wondering if there was a way to automatically generate some kind of GUI shell based on the tables that I could then fill in with the logic / functionality I need.
I have coded and run some of the python / tcl examples that I could find so I kind of get that, but it appears to be a bit labor intensive.

Is there an easier way?

Thanks,

Craig
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090720/9a3d6280/attachment.html>

From tvashtar at gmail.com  Mon Jul 20 11:11:34 2009
From: tvashtar at gmail.com (tvashtar)
Date: Mon, 20 Jul 2009 08:11:34 -0700 (PDT)
Subject: Problem when applying Patch from issue1424152 to get https over 
	authenticating proxies working with urllib2 in Python 2.5
Message-ID: <8fe2ad78-0bd4-40d8-909c-1d2784441e3c@s31g2000yqs.googlegroups.com>

Hi,
I'm trying to get https requests working through an authenticating
proxy with urllib2 in Python 2.5, I'm aware that this isn't supported
"out of the box", so applied the patch http://bugs.python.org/file9753/http-tunnel-urllib
linked from http://bugs.python.org/issue1424152 , my baseline test
program is the following:

p = "user:pass at proxy:port"
proxy_handler = urllib2.ProxyHandler({"http": p, "https": p})
urllib2.install_opener( urllib2.build_opener( urllib2.HTTPHandler,
 
urllib2.HTTPSHandler,
 
proxy_handler))

request = urllib2.Request( "https://groups.google.com")
response = urllib2.urlopen(request)

Unfortunately this doesn't work, the call stack being:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 121, in urlopen
    return _opener.open(url, data)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 374, in open
    response = self._open(req, data)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 392, in _open
    '_open', req)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 353, in _call_chain
    result = func(*args)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 1108, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 1075, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error (1, 'error:140770FC:SSL
routines:SSL23_GET_SERVER_HELLO:unknown protocol')>

Does anyone know why I might be hitting this issue?
Any help is greatly appreciated,
thanks


From nikekoo at gmail.com  Mon Jul 20 11:42:15 2009
From: nikekoo at gmail.com (Nike)
Date: Mon, 20 Jul 2009 08:42:15 -0700 (PDT)
Subject: Problem when applying Patch from issue1424152 to get https over 
	authenticating proxies working with urllib2 in Python 2.5
References: <8fe2ad78-0bd4-40d8-909c-1d2784441e3c@s31g2000yqs.googlegroups.com>
Message-ID: <58f2558c-33fe-4ee0-9a0a-2563374be47c@x6g2000prc.googlegroups.com>

On Jul 20, 11:11?pm, tvashtar <tvash... at gmail.com> wrote:
> Hi,
> I'm trying to get https requests working through an authenticating
> proxy with urllib2 in Python 2.5, I'm aware that this isn't supported
> "out of the box", so applied the patchhttp://bugs.python.org/file9753/http-tunnel-urllib
> linked fromhttp://bugs.python.org/issue1424152, my baseline test
> program is the following:
>
> p = "user:pass at proxy:port"
> proxy_handler = urllib2.ProxyHandler({"http": p, "https": p})
> urllib2.install_opener( urllib2.build_opener( urllib2.HTTPHandler,
>
> urllib2.HTTPSHandler,
>
> proxy_handler))
>
> request = urllib2.Request( "https://groups.google.com")
> response = urllib2.urlopen(request)
>
> Unfortunately this doesn't work, the call stack being:
>
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 121, in urlopen
> ? ? return _opener.open(url, data)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 374, in open
> ? ? response = self._open(req, data)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 392, in _open
> ? ? '_open', req)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 353, in _call_chain
> ? ? result = func(*args)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 1108, in https_open
> ? ? return self.do_open(httplib.HTTPSConnection, req)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 1075, in do_open
> ? ? raise URLError(err)
> urllib2.URLError: <urlopen error (1, 'error:140770FC:SSL
> routines:SSL23_GET_SERVER_HELLO:unknown protocol')>
>
> Does anyone know why I might be hitting this issue?
> Any help is greatly appreciated,
> thanks

hi!
 It's looks like a ssl error . Under the following step to help u :
  1. takes a simple code to confirm your pupose without ssl protocol.
  2. to confirm python version and extended libs work well
  3. to confirm ssl work well.

goog luck!

nikekoo


From hyugaricdeau at gmail.com  Mon Jul 20 11:52:39 2009
From: hyugaricdeau at gmail.com (Hyuga)
Date: Mon, 20 Jul 2009 08:52:39 -0700 (PDT)
Subject: are user defined classes hashable?
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<mailman.3392.1248012803.8015.python-list@python.org> 
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net>
	<mailman.3396.1248018412.8015.python-list@python.org>
Message-ID: <373d6c69-6965-4a88-bdd2-8028ef850bf8@k6g2000yqn.googlegroups.com>

On Jul 19, 11:39?am, Nicolas Dandrimont <Nicolas.Dandrim... at crans.org>
wrote:
> * Alan G Isaac <alan.is... at gmail.com> [2009-07-19 14:46:12 +0000]:
>
> > Again, my question is about the class not its instances,
> > but still, checking as you suggest gives the same answer.
>
> That's what I get for answering before my coffee!

Regardless, Nicolas's example can be applied to the class too:

>>> class Foo(object):
	pass

>>> hash(Foo)
11443104
>>> id(Foo)
11443104

class objects are just objects of type 'type'.


From dtgeadamo at yahoo.com  Mon Jul 20 11:55:35 2009
From: dtgeadamo at yahoo.com (mistersexy)
Date: Mon, 20 Jul 2009 08:55:35 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
Message-ID: <a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>

On Jul 20, 3:03?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> mistersexy wrote:
> > I am trying to create a Windows service in Python using pywin32. I do
> > not want this service to run under a user account. I want this service
> > to be able to run as a LocalService, NetworkService and the like. How
> > do I specify this using the win32 library? Thanks, everyone.
>
> When you "install" the service, using the HandleCommandLine
> option, specify --username= and --password options.
>
> TJG

That's exactly my point. I do not want to have to specify username and
password options. For instance, when creating a Windows Service
in .NET, it is possible to specify that the service should run using
the LocalService or NetworkService account. Doing this, you would not
need to specify username and password options. Is there a way to
achieve this in Python?


From aahz at pythoncraft.com  Mon Jul 20 12:00:33 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 09:00:33 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application Server
	0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
Message-ID: <h424b1$gj1$1@panix3.panix.com>

In article <mailman.3416.1248070578.8015.python-announce-list at python.org>,
tkouts  <python-list at python.org> wrote:
>
>I'm pleased to announce the new version of Porcupine Web Application
>Server, a Python based framework that provides front-end and back-end
>technologies for building modern data-centric Web 2.0 applications.
>
>  [...]
>
>QuiX, the server's integrated JavaScript toolkit, has reached the
>major milestone of supporting all the popular browsers including
>Opera, Safari 4 and IE8.  [...]

Out of curiosity, are there any JavaScript toolkits that generate code
that degrades gracefully when JavaScript is disabled?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From vs at it.uu.se  Mon Jul 20 12:09:42 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Mon, 20 Jul 2009 18:09:42 +0200
Subject: On out-of-date Python Applications
In-Reply-To: <4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>
References: <mailman.3387.1247990649.8015.python-list@python.org>	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>	<4A632C9D.2010303@it.uu.se>	<mailman.3397.1248018457.8015.python-list@python.org>	<e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
	<4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>
Message-ID: <4A6496C6.4040606@it.uu.se>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090720/05384fdc/attachment.html>

From mail at timgolden.me.uk  Mon Jul 20 12:14:31 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 20 Jul 2009 17:14:31 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
Message-ID: <4A6497E7.7090908@timgolden.me.uk>

mistersexy wrote:
> On Jul 20, 3:03 pm, Tim Golden <m... at timgolden.me.uk> wrote:
>> mistersexy wrote:
>>> I am trying to create a Windows service in Python using pywin32. I do
>>> not want this service to run under a user account. I want this service
>>> to be able to run as a LocalService, NetworkService and the like. How
>>> do I specify this using the win32 library? Thanks, everyone.
>> When you "install" the service, using the HandleCommandLine
>> option, specify --username= and --password options.
>>
>> TJG
> 
> That's exactly my point. I do not want to have to specify username and
> password options. For instance, when creating a Windows Service
> in .NET, it is possible to specify that the service should run using
> the LocalService or NetworkService account. Doing this, you would not
> need to specify username and password options. Is there a way to
> achieve this in Python?

Sorry, I misread: I mentally removed the "not" in your 'I do not want
this service to run under a user account' and reinserted it
further on!

By default, the service will run as LocalSystem: you
only specify a username to override that default. The value
in Username is passed straight through to the CreateService
Win32 API, and the docs for that:

  http://msdn.microsoft.com/en-us/library/ms682450%28VS.85%29.aspx


say:

"""
lpServiceStartName [in, optional]

    The name of the account under which the service should run. If the service type is SERVICE_WIN32_OWN_PROCESS, use an account name in the form DomainName\UserName. The service process will be logged on as this user. If the account belongs to the built-in domain, you can specify .\UserName.

    If this parameter is NULL, CreateService uses the LocalSystem account. If the service type specifies SERVICE_INTERACTIVE_PROCESS, the service must run in the LocalSystem account.

    If this parameter is NT AUTHORITY\LocalService, CreateService uses the LocalService account. If the parameter is NT AUTHORITY\NetworkService, CreateService uses the NetworkService account.

    A shared process can run as any user.

    If the service type is SERVICE_KERNEL_DRIVER or SERVICE_FILE_SYSTEM_DRIVER, the name is the driver object name that the system uses to load the device driver. Specify NULL if the driver is to use a default object name created by the I/O system.

    A service can be configured to use a managed account or a virtual account. If the service is configured to use a managed service account, the name is the managed service account name. If the service is configured to use a virtual account, specify the name as NT SERVICE\ServiceName. For more information about managed service accounts and virtual accounts, see the Service Accounts Step-by-Step Guide.

        Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP/2000:  Managed service accounts and virtual accounts are not supported until Windows 7 and Windows Server 2008 R2.
"""



So, although I haven't tried it, it looks as though you can pass 
"LocalService" or "NetworkService" and so on if you want to
override the default LocalSystem but don't want to specify a
username/password.

TJG


From ebonak at hotmail.com  Mon Jul 20 12:22:47 2009
From: ebonak at hotmail.com (Esmail)
Date: Mon, 20 Jul 2009 12:22:47 -0400
Subject: comments? storing a function in an object
Message-ID: <h425ks$fo7$1@ger.gmane.org>

Hello all,

I am trying to store a function and some associated information in an
object so that I can later have series of functions in a list that I can
evaluate one at a time.

Right now I am only storing the function itself, the number of
arguments it expects and its string representation. I may add other
information such as the acceptable range for the parameters or other
characteristics such as maximum or minimum.

I wonder if anyone could comment on my implementation and offer
suggestions or constructive criticisms?

The 'loading' of the functions is a bit tedious and of course care
has to be taken to make sure the string representation corresponds to
the actual function computed. It would be nice if there was an
automatic way to convert the function to its string representation.

Comments or problems with the approach I have taken?

Thanks,
Esmail

--

#!/usr/bin/env python

#
# store and represent functions
#

import math

class FunctionException(Exception):
     """ custom exception """
     def __init__(self, value):
         self.parameter = value

     def __str__(self):
         return repr(self.parameter)



class Function(object):
     """ class to represent a function """

     def __init__(self, fn, fn_str, num_vars):
         """
         the function, its string representation, and the number of variables
         """
         self.fn = fn
         self.fn_str = fn_str
         self.num_vars = num_vars


     def eval_fn(self, variables):
         """ size of variables should equal num_vars .. else problem """
         if len(variables) == self.num_vars:
             result = self.fn(*variables)
             return result
         else:
             raise FunctionException('invalid number of args provided - '+
                                     'received %d, expected %d'
                                     %(len(variables), self.num_vars))


     def str(self):
         """ return string representation of function """
         return self.fn_str




def funct1(x):
     ''' small test function '''
     return x * x


def funct2(x, y):
     ''' small test function '''
     return x + y


def funct3(x):
     ''' small test function '''
     return 1000 + (x*x + x) * math.cos(x)





def main():
     """ main method """
     print 'in main'

     fn1 = Function(funct1, 'x * x', 1)
     fn2 = Function(funct2, 'x + y', 2)
     fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)

     for i in range(-10, 10):
         try:

             print 'f(', [i],') =',
             print fn3.str(), ' => ',
             print fn3.eval_fn([i])

         except FunctionException, (ex):
             print ex.parameter



if __name__ == '__main__':
     main()



From dtgeadamo at yahoo.com  Mon Jul 20 12:25:44 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Mon, 20 Jul 2009 09:25:44 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
Message-ID: <1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>

On Jul 20, 5:14?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> mistersexy wrote:
> > On Jul 20, 3:03 pm, Tim Golden <m... at timgolden.me.uk> wrote:
> >> mistersexy wrote:
> >>> I am trying to create a Windows service in Python using pywin32. I do
> >>> not want this service to run under a user account. I want this service
> >>> to be able to run as a LocalService, NetworkService and the like. How
> >>> do I specify this using the win32 library? Thanks, everyone.
> >> When you "install" the service, using the HandleCommandLine
> >> option, specify --username= and --password options.
>
> >> TJG
>
> > That's exactly my point. I do not want to have to specify username and
> > password options. For instance, when creating a Windows Service
> > in .NET, it is possible to specify that the service should run using
> > the LocalService or NetworkService account. Doing this, you would not
> > need to specify username and password options. Is there a way to
> > achieve this in Python?
>
> Sorry, I misread: I mentally removed the "not" in your 'I do not want
> this service to run under a user account' and reinserted it
> further on!
>
> By default, the service will run as LocalSystem: you
> only specify a username to override that default. The value
> in Username is passed straight through to the CreateService
> Win32 API, and the docs for that:
>
> ?http://msdn.microsoft.com/en-us/library/ms682450%28VS.85%29.aspx
>
> say:
>
> """
> lpServiceStartName [in, optional]
>
> ? ? The name of the account under which the service should run. If the service type is SERVICE_WIN32_OWN_PROCESS, use an account name in the form DomainName\UserName. The service process will be logged on as this user. If the account belongs to the built-in domain, you can specify .\UserName.
>
> ? ? If this parameter is NULL, CreateService uses the LocalSystem account. If the service type specifies SERVICE_INTERACTIVE_PROCESS, the service must run in the LocalSystem account.
>
> ? ? If this parameter is NT AUTHORITY\LocalService, CreateService uses the LocalService account. If the parameter is NT AUTHORITY\NetworkService, CreateService uses the NetworkService account.
>
> ? ? A shared process can run as any user.
>
> ? ? If the service type is SERVICE_KERNEL_DRIVER or SERVICE_FILE_SYSTEM_DRIVER, the name is the driver object name that the system uses to load the device driver. Specify NULL if the driver is to use a default object name created by the I/O system.
>
> ? ? A service can be configured to use a managed account or a virtual account. If the service is configured to use a managed service account, the name is the managed service account name. If the service is configured to use a virtual account, specify the name as NT SERVICE\ServiceName. For more information about managed service accounts and virtual accounts, see the Service Accounts Step-by-Step Guide.
>
> ? ? ? ? Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP/2000: ?Managed service accounts and virtual accounts are not supported until Windows 7 and Windows Server 2008 R2.
> """
>
> So, although I haven't tried it, it looks as though you can pass
> "LocalService" or "NetworkService" and so on if you want to
> override the default LocalSystem but don't want to specify a
> username/password.
>
> TJG

I'll try this stuff. Thanks a million...I'll let everyone know how it
goes.


From bearophileHUGS at lycos.com  Mon Jul 20 12:26:08 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Mon, 20 Jul 2009 09:26:08 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>

William Dode':
> I just tested it with a litle game, to find the places of horse on
> a board 5x5. The result is :
>
> c 5s
> gcj 7s
> java 7s
> shedskin 8s
> python + psyco 18s
> cython avec malloc *int 18s
> cython 55s avec [] python
> python 303s (5m3s)

Nice timings, can you please show me the Python, Java and C code
versions? I may do more tests.
The purpose of all those "example programs" in ShedSkin is to find
bugs and to find details to speedup.

Bye,
bearophile


From phillip.oldham at gmail.com  Mon Jul 20 12:27:05 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Mon, 20 Jul 2009 17:27:05 +0100
Subject: Help understanding the decisions *behind* python?
Message-ID: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>

My colleagues and I have been working with python for around 6 months
now, and while we love a lot of what python has done for us and what
it enables us to do some of the decisions behind such certain
data-types and their related methods baffle us slightly (when compared
to the decisions made in other, similarly powerful languages).

Specifically the "differences" between lists and tuples have us
confused and have caused many "discussions" in the office. We
understand that lists are mutable and tuples are not, but we're a
little lost as to why the two were kept separate from the start. They
both perform a very similar job as far as we can tell.

Consider the following:

>>> x = [2,1,3]
>>> x.sort()
>>> print x
[1, 2, 3]

Now, if the sort operations were unable to affect the original
structure of the list (as in JavaScript) you'd effectively have a
tuple which you could add/remove from, and the example above would
look more like:

>>> x = [2,1,3]
>>> print x.sort()
[1, 2, 3]
>>> print x
[2,1,3]

This make a lot more sense to us, and follows the convention from
other languages. It would also mean chaining methods to manipulate
lists would be easier:

>>> x = [2,1,3]
>>> print x.sort()[0]
3
>>> print x
[2,1,3]

We often find we need to do manipulations like the above without
changing the order of the original list, and languages like JS allow
this. We can't work out how to do this in python though, other than
duplicating the list, sorting, reversing, then discarding.

We're not looking to start any arguments or religious wars and we're
not asking that python be changed into something its not. We'd simply
like to understand the decision behind the lists and tuple structures.
We feel that in not "getting" the difference between the two types we
may be missing out on using these data structures to their full
potential.


From tycho at tycho.ws  Mon Jul 20 12:43:16 2009
From: tycho at tycho.ws (Tycho Andersen)
Date: Mon, 20 Jul 2009 11:43:16 -0500
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
Message-ID: <49b3a7400907200943s2ed382c7qa0a38aa67db79885@mail.gmail.com>

On Mon, Jul 20, 2009 at 11:27 AM, Phillip B
Oldham<phillip.oldham at gmail.com> wrote:
> <snip>
> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.
>

I have no idea about why the design decisions were made. You might
take a look at the sorted() function:
http://docs.python.org/library/functions.html#sorted

It will do what you want.

\t
--
http://tycho.ws


From http  Mon Jul 20 12:50:56 2009
From: http (Paul Rubin)
Date: 20 Jul 2009 09:50:56 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
Message-ID: <7xljmjguxb.fsf@ruckus.brouhaha.com>

vippstar <vippstar at gmail.com> writes:
> > I wonder whether 2/3 => ValueError is preferable.
> 
> Not all software wants this. It shouldn't be part of the language but
> rather part of your code if you need such a feature. (for instance, to
> distinguish between 2/3 and divisions with 0 dividend).

I don't see how to implement such a thing in my code, if I believe
that the ring of integers doesn't have any concept of division and so
attempts to divide integers should be treated as errors.  Yes of
course the present / operator is useful, but I could do just as well
with the divmod function which I think is more explicit.


From marcusw at cox.net  Mon Jul 20 13:06:39 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 13:06:39 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <7x4ot7rif8.fsf@ruckus.brouhaha.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
Message-ID: <h4286v$8ja$1@adenine.netfront.net>

On 7/20/2009 2:13 AM, Paul Rubin wrote:
> Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:
>> Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing 
>> to do. It's the right thing to do if you're doing integer maths.
> 
> I wonder whether 2/3 => ValueError is preferable.
Not for me :(


From duncan.booth at invalid.invalid  Mon Jul 20 13:08:38 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 20 Jul 2009 17:08:38 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <Xns9C4EB8936A361duncanbooth@127.0.0.1>

Phillip B Oldham <phillip.oldham at gmail.com> wrote:

> This make a lot more sense to us, and follows the convention from
> other languages. It would also mean chaining methods to manipulate
> lists would be easier:
> 
>>>> x = [2,1,3]
>>>> print x.sort()[0]
> 3
>>>> print x
> [2,1,3]

You already have a way to do what you want:

>>> x = [2,1,3]
>>> print sorted(x)[0]
3
>>> print x
[2,1,3]

as a bonus you can use 'sorted' to sort any sequence including generators 
or tuples, but the result will always be a list: if it was a list method 
then you would have to convert the sequence to a list first.

The main reason why you need both lists and tuples is that because a tuple 
of immutable objects is itself immutable you can use it as a dictionary 
key. You can't use a list as a dictionary key because if something were to 
mutate a key the dictionary structure would behave very strangely indeed.
The types 'set' and 'frozenset' both exist for the same reason.


From darcy at druid.net  Mon Jul 20 13:08:56 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Mon, 20 Jul 2009 13:08:56 -0400
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
In-Reply-To: <h424b1$gj1$1@panix3.panix.com>
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
Message-ID: <20090720130856.fdee4c6d.darcy@druid.net>

On 20 Jul 2009 09:00:33 -0700
aahz at pythoncraft.com (Aahz) wrote:
> Out of curiosity, are there any JavaScript toolkits that generate code
> that degrades gracefully when JavaScript is disabled?

I understand what you want but I can't see how a toolkit can do that.
How do you program "graceful?"  It seems pretty application specific.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From marcusw at cox.net  Mon Jul 20 13:11:20 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 13:11:20 -0400
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <mailman.3419.1248082444.8015.python-list@python.org>
References: <mailman.3406.1248034495.8015.python-list@python.org>	<h40adj$bv6$1@adenine.netfront.net>
	<mailman.3419.1248082444.8015.python-list@python.org>
Message-ID: <h428fp$8ja$2@adenine.netfront.net>

On 7/20/2009 5:34 AM, Stef Mientki wrote:
> thanks Marcus,
> 
> Marcus Wanner wrote:
>> On 7/19/2009 4:15 PM, Stef Mientki wrote:
>>> hello,
>>>
>>> I'm using Scintilla as a wxPython widget with great pleasure.
>>> I now have an application where I want to make notes during a 
>>> conversation,
>>> but also want to record the speech during that conversation.
>>> I'm using Scintilla as a wxPython widget for editing and PyAudio for 
>>> the speech recording,
>>> until so far everything works fine.
>>>
>>> Here the problem part:
>>> I need to synchronize the typed text with the sound during playback.
>>> So if I click somewhere in the sound recording,
>>> the line of text, typed that moment should be highlighted.
>>> And vise versa, if the cursor in the text is moved and some special 
>>> key is pressed,
>>> the sound starting 10 or 20seconds earlier should be playbacked.
>>>
>>> I though of adding bookmarks (because these are fixed in the text), 
>>> and keep a list of bookmarks and sound pointers.
>>> This idea should work, but there are only 31 bookmarks.
>>>
>>> Any other suggestions ?
>>>
>>> thanks,
>>> Stef Mientki
>> That sounds like a very specialized type of thing, 
> Well from an application point of view,
> with the current netbooks,
> this looks like a perfect tool for any conversation or meeting.
>> which only the few people with experience with wxPython, PyAudio, and 
>> Scintilla could help you with...
>>
> I was afraid of that too, so I dropped the question in several places,
> and the writer of Scintilla himself came with the perfect answer.
> 
> cheers,Stef
>> But you might try having a dictionary with notes and associated times, 
>> or just give each note a four-digit ID number at the beginning of it 
>> when it's entered and use that in the dictionary (to keep keys 
>> shorter). Or you could just do a little hack and increase the number 
>> of bookmarks allowed (seeing as source is available) :p
>>
>> Marcus
> 
Glad you got a good answer from somebody. Sounds like an interesting 
project. About when would this be headed for a release? Could you post a 
link to a googlecode or sourceforge project or something so I can follow 
and/or help with development?

Marcus


From motoom at xs4all.nl  Mon Jul 20 13:17:19 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Mon, 20 Jul 2009 19:17:19 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
Message-ID: <4A64A69F.2030400@xs4all.nl>

Phillip wrote:

> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.

Yes, but because of their immutability you can use tuples as dictionary 
keys (only if they contain immutable objects).
Lists can't be used as dictionary keys.

Greetings,

-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From gerard.blais at gmail.com  Mon Jul 20 13:28:09 2009
From: gerard.blais at gmail.com (MCIPERF)
Date: Mon, 20 Jul 2009 10:28:09 -0700 (PDT)
Subject: win32api install problem
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
	<mailman.3424.1248098235.8015.python-list@python.org>
Message-ID: <b1b9ef55-c740-4a9e-ba33-4aa1e88dc5f5@f33g2000vbm.googlegroups.com>

On Jul 20, 9:57?am, Tim Golden <m... at timgolden.me.uk> wrote:
> Gerry wrote:
> > I'm running Python 2.6 under XP.
>
> > I've installed Windows 32 extensions for Python 2.6 version 1.4
> > (pywin32-214.win32-py2.6.exe).
>
> > But If I try to import win32api, I get:
>
> > ? File "C:\python_projects\euler\driveletters.py", line 1, in <module>
> > ? ? import win32api
> > ImportError: DLL load failed: The specified module could not be found.
>
> Used to be you'd get this error if you installed as a
> non-admin user. Don't know if that's still an issue.
> Possibility?
>
> TJG

Not a possibility (afaict) -- I am an administrator, according to the
control panel.


From marcusw at cox.net  Mon Jul 20 13:42:55 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 13:42:55 -0400
Subject: Design question.
In-Reply-To: <68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
	<mailman.3423.1248095131.8015.python-list@python.org>
	<68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
Message-ID: <h42abb$9nk$1@adenine.netfront.net>

On 7/20/2009 9:42 AM, Lacrima wrote:
> On Jul 20, 4:05 pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
> wrote:
>> Lacrima wrote:
>>> Hello!
>>> I am newbie in python and I have really simple question, but I need
>>> your advice to know how to do best.
>>> I need to store a number of dictionaries in certain place. I've
>>> decided to store them in a separate module.
>>> Like this:
>>> dicts.py
>>> -----------------------
>>> dict1 = {....}
>>> dict2 = {....}
>>> dict3 = {....}
>>> Then, when I need any dictionary, I can access it:
>>> import dicts
>>> dicts.dict1
>>> Is it a good practice? Or should I store them as class attributes or
>>> anything else?
>>> Thanks in advance.
>>> With regards, Max
>>> (sorry if my English isn't very proper)
>> Defining dict as a module attribute ic correct, but try to answer the
>> following question:
>>
>> Is dict1 an attribute/property/declension of the object/entity defined
>> by the module dicts ?
>> If yes, then your design is correct.
>>
>> An correct example:
>> fruits.py
>> ------------
>> apple = {}
>> banana = {}
>>
>> An incorrect one:
>> fruit.py
>> -----------
>> apple={}
>> bicycle={}
>>
>> Basically, the rule is very straightforward, set your dict as a module
>> attribute only if its one of its attribute (very nice paraphrase !)
>> Most of people (including me) tend to have a  module, where they put
>> everything they have no idea about their location. This is a bad habit
>> and result from a uncontrolled/undocumented design. Usually documenting
>> objects in such modules is really painful.
>>
>> Your proposal is fine from a python syntax point of view. I can't tell
>> of your design with names like (dicts.py and dict1,dict2) hoping you do
>> not intend to name them that way.
>>
>> JM
> 
> Hi, Jean-Michel!
> 
> Thanks for your answer.
> I am not going to have names like dicts.py and dict1,dict2. That was
> just example. I wanted to know if it is correct to have dictionaries
> on a module level. Now I know that this is correct. I want to collect
> in one module a number of dictionaries, every of which describes a
> separate web service. And my function in another module will import
> required dictionary, depending on what web service should be used.
> Thanks again for the help.
> 
> With regards,
> Max.
> (sorry if my English isn't very proper)
Yeah, you can put just about anything in a separate module/file, but 
putting unrelated things in the same module is bad...

For example, if you have apple and banana in a module, and had a 
function called slicefruit() to do something to those variables in there 
with them, then that would be good. But if you put bicycle and car and 
adjustbrakes() in the module with the fruits, or mixed the two groups in 
several modules, that would be bad.

Marcus


From bieffe62 at gmail.com  Mon Jul 20 13:44:16 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Mon, 20 Jul 2009 10:44:16 -0700 (PDT)
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
Message-ID: <3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>

On Jul 20, 6:22?pm, Esmail <ebo... at hotmail.com> wrote:
> Hello all,
>
> I am trying to store a function and some associated information in an
> object so that I can later have series of functions in a list that I can
> evaluate one at a time.
>
> Right now I am only storing the function itself, the number of
> arguments it expects and its string representation. I may add other
> information such as the acceptable range for the parameters or other
> characteristics such as maximum or minimum.
>
> I wonder if anyone could comment on my implementation and offer
> suggestions or constructive criticisms?
>
> The 'loading' of the functions is a bit tedious and of course care
> has to be taken to make sure the string representation corresponds to
> the actual function computed. It would be nice if there was an
> automatic way to convert the function to its string representation.
>
> Comments or problems with the approach I have taken?
>
> Thanks,
> Esmail
>
> --
>
> #!/usr/bin/env python
>
> #
> # store and represent functions
> #
>
> import math
>
> class FunctionException(Exception):
> ? ? ?""" custom exception """
> ? ? ?def __init__(self, value):
> ? ? ? ? ?self.parameter = value
>
> ? ? ?def __str__(self):
> ? ? ? ? ?return repr(self.parameter)
>
> class Function(object):
> ? ? ?""" class to represent a function """
>
> ? ? ?def __init__(self, fn, fn_str, num_vars):
> ? ? ? ? ?"""
> ? ? ? ? ?the function, its string representation, and the number of variables
> ? ? ? ? ?"""
> ? ? ? ? ?self.fn = fn
> ? ? ? ? ?self.fn_str = fn_str
> ? ? ? ? ?self.num_vars = num_vars
>
> ? ? ?def eval_fn(self, variables):
> ? ? ? ? ?""" size of variables should equal num_vars .. else problem """
> ? ? ? ? ?if len(variables) == self.num_vars:
> ? ? ? ? ? ? ?result = self.fn(*variables)
> ? ? ? ? ? ? ?return result
> ? ? ? ? ?else:
> ? ? ? ? ? ? ?raise FunctionException('invalid number of args provided - '+
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?'received %d, expected %d'
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?%(len(variables), self.num_vars))
>
> ? ? ?def str(self):
> ? ? ? ? ?""" return string representation of function """
> ? ? ? ? ?return self.fn_str
>
> def funct1(x):
> ? ? ?''' small test function '''
> ? ? ?return x * x
>
> def funct2(x, y):
> ? ? ?''' small test function '''
> ? ? ?return x + y
>
> def funct3(x):
> ? ? ?''' small test function '''
> ? ? ?return 1000 + (x*x + x) * math.cos(x)
>
> def main():
> ? ? ?""" main method """
> ? ? ?print 'in main'
>
> ? ? ?fn1 = Function(funct1, 'x * x', 1)
> ? ? ?fn2 = Function(funct2, 'x + y', 2)
> ? ? ?fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)
>
> ? ? ?for i in range(-10, 10):
> ? ? ? ? ?try:
>
> ? ? ? ? ? ? ?print 'f(', [i],') =',
> ? ? ? ? ? ? ?print fn3.str(), ' => ',
> ? ? ? ? ? ? ?print fn3.eval_fn([i])
>
> ? ? ? ? ?except FunctionException, (ex):
> ? ? ? ? ? ? ?print ex.parameter
>
> if __name__ == '__main__':
> ? ? ?main()


I can offer some small suggestions: it is up to you to evaluate if
they make sense for your app:

1. use __doc__ function standard attribute for function description
(your fn_str); this meanst that
   you do not need fm_str in the constructor and you have to do e.g. :

def funct2(x, y):
      ''' x + y '''
      return x + y

then funct2.__doc__  becomes the string you want to associate to the
function

2. Use __call__ instead of eval_fn : this way, the instance of your
Function became a 'callable' and can be used
   everywhere a function is needed. You can do:

   f = Function(...)
   f( some_args )

3. If you call a python function with wrong number of arguments, it
already raises a TypeError exception which contains
   - with different wording - the same information of your
FunctionException : consider removing the check and using the
   python error instead


HTH

Ciao
------
FB




From drobinow at gmail.com  Mon Jul 20 13:46:26 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 20 Jul 2009 13:46:26 -0400
Subject: On out-of-date Python Applications
In-Reply-To: <4A6496C6.4040606@it.uu.se>
References: <mailman.3387.1247990649.8015.python-list@python.org>
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>
	<4A632C9D.2010303@it.uu.se>
	<mailman.3397.1248018457.8015.python-list@python.org>
	<e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
	<4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>
	<4A6496C6.4040606@it.uu.se>
Message-ID: <4eb0089f0907201046x4bdc3b10t3ad56a888526eff2@mail.gmail.com>

On Mon, Jul 20, 2009 at 12:09 PM, Virgil Stokes<vs at it.uu.se> wrote:
> David Robinow wrote:
>
> On Mon, Jul 20, 2009 at 7:24 AM, John Machin<sjmachin at lexicon.net> wrote:
> ...
>
>
> The next step would be to try to compile ODE 0.7 or 0.8 with VS9 --
> however this would require "project files" for ODE for VS9, and there
> aren't any on the ODE website; it has only those for VS3 and VS5.
>
>
>
>  The ODE site is a mess.
> Go to http://www.ode.org/svn.html  and click on:   Instructions for
> accessing the repository
>  Scroll down to the section "Building with Premake"
>  (Note that there is no directory "ode/build" -- you want the "build"
> directory, which contains premake4.exe)
> I used "premake4 --with-demos --with-tests vs2008"
> I have successfully compiled ode-0.11.1 using these instructions. I
> have not yet run the tests or demos or tried to compile PyODE.
>
>
> Thanks for this information David.
> Now that you have successfully compiled ode-0.11.1, how can one finish this
> process --- compile PyODE?
>
> --V
>
Edit setup.py       Windows specific settings:
 ODE_BASE to location of your ode distribution
 create releaselib directory under lib and copy the .lib file that you built in
Visual Studio.  This will be:
   ReleaseSingleLib\ode_single.lib  or
   ReleaseDoubleLib\ode_double.lib  or one of the Debug versions
 Change the name to ode.lib.
 i.e. in CMD-speak:  %ODE_BASE%\lib\releaselib\ode.lib

I was then able to build PyODE-1.2.0

However, all the examples died with:
  ODE Message 2: mass must be > 0 <..\..\ode\src\mass.cpp:49)

I don't have time right now to debug this. Maybe somebody else can take it a
bit further.


From tvashtar at gmail.com  Mon Jul 20 13:58:53 2009
From: tvashtar at gmail.com (tvashtar)
Date: Mon, 20 Jul 2009 10:58:53 -0700 (PDT)
Subject: Problem when applying Patch from issue1424152 to get https over 
	authenticating proxies working with urllib2 in Python 2.5
References: <8fe2ad78-0bd4-40d8-909c-1d2784441e3c@s31g2000yqs.googlegroups.com>
	<58f2558c-33fe-4ee0-9a0a-2563374be47c@x6g2000prc.googlegroups.com>
Message-ID: <446a3c42-6d86-4003-85be-3e5d8a23b268@c14g2000yqm.googlegroups.com>

On Jul 20, 4:42?pm, Nike <nike... at gmail.com> wrote:
> hi!
> ?It's looks like a ssl error . Under the following step to help u :
> ? 1. takes a simple code to confirm your pupose without ssl protocol.
> ? 2. to confirm python version and extended libs work well
> ? 3. to confirm ssl work well.
>
> goog luck!
>
> nikekoo

I've reduced my code to the following:

import urllib2

p = "https://user:pass at myproxy:port"
proxy_handler = urllib2.ProxyHandler({"https": p})
urllib2.install_opener(urllib2.build_opener(proxy_handler))
request = urllib2.Request( "https://groups.google.com")
response = urllib2.urlopen(request)

and it is now failing with:

Traceback (most recent call last):
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\test.py", line 12, in <module>
    response = urllib2.urlopen(request)
  File "C:\Python25\lib\urllib2.py", line 121, in urlopen
    return _opener.open(url, data)
  File "C:\Python25\lib\urllib2.py", line 379, in open
    response = self._open(req, data)
  File "C:\Python25\lib\urllib2.py", line 397, in _open
    '_open', req)
  File "C:\Python25\lib\urllib2.py", line 358, in _call_chain
    result = func(*args)
  File "C:\Python25\lib\urllib2.py", line 1115, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "C:\Python25\lib\urllib2.py", line 1082, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error Tunnel connection failed: 407 Proxy
Authentication Required>

I thought the proxy_handler should take care of the authentication?

Thanks for your help


From kiorky at cryptelium.net  Mon Jul 20 14:19:43 2009
From: kiorky at cryptelium.net (kiorky)
Date: Mon, 20 Jul 2009 20:19:43 +0200
Subject: Compilation problem with Python < 2.6 and db >= 4.7
Message-ID: <4A64B53F.8060502@cryptelium.net>

Is there a way to make the bsddb module compile against db>=4.7 for python < 2.6
(2.4.6, 2.5.4)? A patch ? A tip ?

For the moment, i have a known failure as:
gcc -pthread -fno-strict-aliasing -DNDEBUG
-I/usr/home/kiorky/minitage/dependencies/readline-5.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/bzip2-1.0/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/zlib-1.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/db-4.7/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/expat-2.0/parts/part/include  -I.
-IInclude -I./Include
-I/usr/home/kiorky/minitage/dependencies/readline-5.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/bzip2-1.0/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/zlib-1.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/db-4.7/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/expat-2.0/parts/part/include -fPIC
-DPy_BUILD_CORE
-I/usr/home/kiorky/minitage/dependencies/db-4.7/parts/part/include -c
./Modules/_bsddb.c -o Modules/_bsddb.o
./Modules/_bsddb.c: In function 'DBEnv_getattr':
./Modules/_bsddb.c:5337: error: 'DB_ENV' has no member named 'db_home'
./Modules/_bsddb.c:5340: error: 'DB_ENV' has no member named 'db_home'
./Modules/_bsddb.c: In function 'init_bsddb':
./Modules/_bsddb.c:5962: error: 'DB_LOG_AUTOREMOVE' undeclared (first use in
this function)
./Modules/_bsddb.c:5962: error: (Each undeclared identifier is reported only once
./Modules/_bsddb.c:5962: error: for each function it appears in.)
./Modules/_bsddb.c:5963: error: 'DB_DIRECT_LOG' undeclared (first use in this
function)
./Modules/_bsddb.c:5971: error: 'DB_LOG_INMEMORY' undeclared (first use in this
function)
*** Error code 1


I looked for the one inside python >= 2.6 and it seems to have changed a lot so
backporting it seems difficult and maybe break the old API.

I didn't find something on it.

-- 
--
Cordialement,
KiOrKY
GPG Key FingerPrint: 0x1A1194B7681112AF



From anthony.tolle at gmail.com  Mon Jul 20 14:22:52 2009
From: anthony.tolle at gmail.com (Anthony Tolle)
Date: Mon, 20 Jul 2009 11:22:52 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <df4aeb36-6a4d-49a6-82f1-6ab54862afae@18g2000yqa.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> ...
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
> ...

There's no hard-set rules, but tuples are typically used to hold
collections of heterogeneous data, e.g. (10, "spam", 3.21).  As has
been mentioned, such a tuple can be used as a dictionary key, whereas
a list cannot be used as a dictionary key, because it is mutable.

Lists, on the other hand, typically hold collections of homogeneous
data, e.g. [1, 2, 5] or ["spam", "eggs", "sausage"].

Of course, you'll also see plenty of examples of tuples containing
homogeneous data and lists containing heterogeneous data :)


From lenz at joinville.udesc.br  Mon Jul 20 14:26:50 2009
From: lenz at joinville.udesc.br (Eduardo Lenz)
Date: Mon, 20 Jul 2009 11:26:50 -0700
Subject: ANN: psyco V2
In-Reply-To: <4A5FE672.3000401@stackless.com>
References: <4A5FE672.3000401@stackless.com>
Message-ID: <200907201126.51878.lenz@joinville.udesc.br>

Em Qui 16 Jul 2009, ??s 19:48:18, Christian Tismer escreveu:
> Announcing Psyco V2 source release
> ----------------------------------
>
> This is the long awaited announcement of Psyco V2.
>
> Psyco V2 is a continuation of the well-known psyco project,
> which was called finished and was dis-continued by its author
> Armin Rigo in 2005, in favor of the PyPy project.
>
> This is a new project, using Psyco's code base with permission
> of Armin. Questions and complaints should go to me
> (tismer at stackless.com) or the mailing list
> (psyco-devel at lists.sourceforge.net);
> Armin is explicitly not in charge of (t)his project any longer!
>
> As one of the founders and an active member of the PyPy
> project, I was very happy to be invited to work on Psyco
> V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
> approach "an extension module that just makes Python faster".
>
> Psyco is a just-in-time compiler that accelerates arbitrary
> Python code by specialization. We believe that Psyco's approach
> can be carried out much further than it was tried so far, when
> it's first version was abandoned.
>
> This first V2 release is source-only. There is no web-site, yet,
> and there are no binaries for download. These will be available
> in a few days on http://www.psyco.org .
>
> For the time being, please stick with subversion access,
> building the extension module from source code. The repository
> is here:
>
>      http://codespeak.net/svn/psyco/v2/dist
>
> Check-out the repository, and run the setup.py script,
> given that you have access to a C compiler.
>
> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
> is well being considered.
>
> The current improvements are, shortly:
>
>    - Support for Python 2.4, 2.5 and 2.6
>    - a lot of new builtins
>    - generators, fast and fully supported.
>
> More information is coming soon on http://www.psyco.org .
>
> This is the beginning of a series of new Psyco versions.
> Many more improvements are prepared and about to be published,
> soon, starting with the current version 2.0.0 .
>
> Stay tuned, this is just the beginning of psyco's re-birth!
>
> For questions about Psyco V2, please join the mailing list
>
>      psyco-devel at lists.sourceforge.net
>
> or contact me on IRC:
>
>      #psyco on irc.freenode.net .
>
> Psyco V2 is fundamentally supported by FATTOC, LLC.
> See http://www.fattoc.com .
>
> Without their continuous support, this work would not have
> been possible at all. I wish to express my deepest thanks
> to FATTOC, for allowing me to continue on Psyco with all the
> energy that this ambitious project needs, and will need.
>
> Further special thanks are going to
> Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
> Raymond Hettinger, Fabrizio Milo, Michael Foord,
> Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
> for all the support and discussions.
>
> Looking forward to a great future of Psyco!
>
> July 17, 2009
I know its not the proper list but....

gcc -pthread -fno-strict-aliasing -fwrapv -Wall -Wstrict-prototypes -DNDEBUG -
g -O3 -fPIC -Ic/i386 -Ic -I/usr/include/python2.6 -c c/mergepoints.c -o 
build/temp.linux-i686-2.6/c/mergepoints.o
c/mergepoints.c:250: error: ???RAISE_VARARGS??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???JUMP_IF_FALSE??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???JUMP_IF_TRUE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???DUP_TOPX??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???IMPORT_STAR??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???SLICE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???STORE_SLICE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???DELETE_SLICE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???PRINT_EXPR??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???PRINT_ITEM??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???PRINT_ITEM_TO??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???PRINT_NEWLINE??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???PRINT_NEWLINE_TO??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???BUILD_CLASS??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???IMPORT_NAME??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???IMPORT_FROM??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???MAKE_FUNCTION??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???BUILD_SLICE??? undeclared here (not in a function)
error: command 'gcc' failed with exit status 1

any clue ?

[]'s
Eduardo

 Tel: +55 47 4009-7971 - Fax: +55 47 4009-7940
 E-mail: lenz at Joinville.udesc.br          
 ---------------------------------------------

-- 
Esta mensagem foi verificada pelo sistema de antiv?rus e
 acredita-se estar livre de perigo.



From skip at pobox.com  Mon Jul 20 14:26:56 2009
From: skip at pobox.com (skip at pobox.com)
Date: Mon, 20 Jul 2009 13:26:56 -0500
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <4a645b81$0$12974$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <19044.46832.524925.930667@montanaro.dyndns.org>


    William> c 5s
    William> gcj 7s
    William> java 7s
    William> shedskin 8s
    William> python + psyco 18s
    William> cython avec malloc *int 18s
    William> cython 55s avec [] python
    William> python 303s (5m3s)

I read just enough French to know that "avec" means "with", but I don't
understand the difference between "avec malloc *int" and "avec []".  Can you
explain please?

Thx,

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    That's more than a dress. That's an Audrey Hepburn movie. -- Jerry Maguire


From vippstar at gmail.com  Mon Jul 20 14:31:08 2009
From: vippstar at gmail.com (vippstar)
Date: Mon, 20 Jul 2009 11:31:08 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com> 
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com> 
	<7xljmjguxb.fsf@ruckus.brouhaha.com>
Message-ID: <7a04b07d-2dea-455f-bafd-33461ce25a1a@q11g2000yqi.googlegroups.com>

On Jul 20, 7:50?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> vippstar <vipps... at gmail.com> writes:
> > > I wonder whether 2/3 => ValueError is preferable.
>
> > Not all software wants this. It shouldn't be part of the language but
> > rather part of your code if you need such a feature. (for instance, to
> > distinguish between 2/3 and divisions with 0 dividend).
>
> I don't see how to implement such a thing in my code,
Write a function:

  (if (< x y)
      ValueError
      (/ x y))

This will return 0 only if the dividend = 0, not in integer division x/
y with y > x, which will return ValueError. Of course, ValueError must
not be an integer, because that could be the result of an integer
division. If it's not possible to return multiple types, then the
function can make use of some error handling mechanism.

> if I believe that the ring of integers doesn't have any concept
> of division and so attempts to divide integers should be treated
> as errors.

Wouldn't that mean 3/2 would also evaluate to ValueError? But 3/2 = 1
in integer division, not 0, like 2/3. Regardless, it's a specialized
requirement, and thus should either be implemented by the programmer
or the language could provide it if it's specialized, (for instance, I
wouldn't require a language to provide text manipulation features, but
I expect them from perl because it's not a general all purpose
language [the name designates that, however it can be used as one -
like lisp])

> course the present / operator is useful, but I could do just as well
> with the divmod function which I think is more explicit.
What? Python? Aww.


From bearophileHUGS at lycos.com  Mon Jul 20 14:51:18 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Mon, 20 Jul 2009 11:51:18 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<mailman.3437.1248114427.8015.python-list@python.org>
Message-ID: <04f03d96-46b7-4761-8498-9149f19ecba6@k6g2000yqn.googlegroups.com>

Skip Montanaro:
> I read just enough French to know that "avec" means "with", but I don't
> understand the difference between "avec malloc *int" and "avec []". ?Can you
> explain please?

Maybe it's the time difference between using a Python list from Cython
and using a C "array" allocated with a malloc from Cython.

Bye,
bearophile


From mark.dufour at gmail.com  Mon Jul 20 15:20:55 2009
From: mark.dufour at gmail.com (srepmub)
Date: Mon, 20 Jul 2009 12:20:55 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
Message-ID: <e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>


> Nice timings, can you please show me the Python, Java and C code
> versions? I may do more tests.

also, which shedskin options did you use? did you use -bw, to disable
bounds and wrap-around checking? this can make quite a difference for
code that does a lot of indexing. if the code uses random numbers,
then -r can also make a big difference, to use C rand(), instead of
Python compatible random numbers.

and which C++ compiler flags did you use? the default -O2, or
something like -O3 -fomit-frame-pointer -msse2..?


thanks,
mark.


From phillip.oldham at gmail.com  Mon Jul 20 15:26:07 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Mon, 20 Jul 2009 12:26:07 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
Message-ID: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>

On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> The main reason why you need both lists and tuples is that because a tuple
> of immutable objects is itself immutable you can use it as a dictionary
> key.

Really? That sounds interesting, although I can't think of any real-
world cases where you'd use something like that.


From duncan.booth at invalid.invalid  Mon Jul 20 15:54:02 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 20 Jul 2009 19:54:02 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <Xns9C4ED49939240duncanbooth@127.0.0.1>

Phillip B Oldham <phillip.oldham at gmail.com> wrote:

> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>> The main reason why you need both lists and tuples is that because a
>> tuple of immutable objects is itself immutable you can use it as a
>> dictionary key.
> 
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.
> 

How about a multi-dimensional sparse array?

>>> d = {}
>>> d[1,2] = 'a'
>>> d[5,7] = 'b'



From marcusw at cox.net  Mon Jul 20 16:12:45 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 16:12:45 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <h42j49$2m2$1@adenine.netfront.net>

On 7/20/2009 3:26 PM, Phillip B Oldham wrote:
> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>> The main reason why you need both lists and tuples is that because a tuple
>> of immutable objects is itself immutable you can use it as a dictionary
>> key.
> 
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.
Actually, that would be very useful in the program from "any suggestions 
to synchronize typed text and speech ?"...i.e. have a dictionary key of 
(hour, minute, second).

Marcus


From jcd at sdf.lonestar.org  Mon Jul 20 16:15:16 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Mon, 20 Jul 2009 16:15:16 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <1248120917.5967.5.camel@aalcdl07>

On Mon, 2009-07-20 at 12:26 -0700, Phillip B Oldham wrote:
> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> > The main reason why you need both lists and tuples is that because a tuple
> > of immutable objects is itself immutable you can use it as a dictionary
> > key.
> 
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.

Well, if you wanted to index a dictionary by coordinates, you might do
something like this:


fleet = {}
fleet[9,4] = 'destroyer'
fleet[8,4] = 'destroyer'
fleet[3,5] = 'aircraftcarrier'
fleet[4,5] = 'aircraftcarrier'
fleet[5,5] = 'aircraftcarrier'
fleet[6,5] = 'aircraftcarrier'
fleet[8,0] = 'battleship'
fleet[8,1] = 'battleship'
fleet[8,2] = 'battleship'


def checkattack(x, y, fleet):
    if x,y in fleet:
        return "You hit my %s' % fleet[x,y]

Maybe not the best implementation of Battleship, but you get the idea.





From mrstevegross at gmail.com  Mon Jul 20 16:38:57 2009
From: mrstevegross at gmail.com (mrstevegross)
Date: Mon, 20 Jul 2009 13:38:57 -0700 (PDT)
Subject: How to import pydoc and then use it?
Message-ID: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>

I know how to use pydoc from the command line. However, because of
complicated environmental setup, it would be preferable to run it
within a python script as a native API call. That is, my python runner
looks a bit like this:

  import pydoc
  pydoc.generate_html_docs_for(someFile)

However, it's not clear to me from the pydoc documentation which
function calls I need to use to make this behavior work. Any ideas?

Thanks,
--Steve


From nytrokiss at gmail.com  Mon Jul 20 17:01:13 2009
From: nytrokiss at gmail.com (James Matthews)
Date: Tue, 21 Jul 2009 00:01:13 +0300
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
In-Reply-To: <e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
Message-ID: <8a6b8e350907201401k383b0982ma7aeaaf8bf7d7f8a@mail.gmail.com>

I like this, I am going to run this as a test. I also want to see the source
code on how they compile the dynamic variables.

On Mon, Jul 20, 2009 at 10:20 PM, srepmub <mark.dufour at gmail.com> wrote:

>
> > Nice timings, can you please show me the Python, Java and C code
> > versions? I may do more tests.
>
> also, which shedskin options did you use? did you use -bw, to disable
> bounds and wrap-around checking? this can make quite a difference for
> code that does a lot of indexing. if the code uses random numbers,
> then -r can also make a big difference, to use C rand(), instead of
> Python compatible random numbers.
>
> and which C++ compiler flags did you use? the default -O2, or
> something like -O3 -fomit-frame-pointer -msse2..?
>
>
> thanks,
> mark.
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.jewelerslounge.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/24cdf130/attachment.html>

From egon.frerich at nord-com.net  Mon Jul 20 17:07:38 2009
From: egon.frerich at nord-com.net (Egon Frerich)
Date: Mon, 20 Jul 2009 23:07:38 +0200
Subject: locale doesn' format
Message-ID: <4A64DC9A.3060606@nord-com.net>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I want to format values to the german form eg. 1.034,56 but
locale.format() doesn't work for me.

Here is a little test program:

import decimal, locale

print locale.getdefaultlocale()
print locale.localeconv()
locale.setlocale(locale.LC_ALL, ('de_DE', 'UTF-8'))
print locale.localeconv()
k = decimal.Decimal('1034.56')
#k = 1034.56
print 'k', k, type(k)
k1 = locale.format_string('%12s',k,True)
print 'k1', k1, type(k1)
k1a = locale.format('%12s',k,True,True)
print 'k1a', k1a, type(k1a)
k2 = unicode(k1)
print 'k2',k2,type(k2)
print k1.find(',')
print k1a.find(',')
print k2.find(',')
ab = locale.localeconv()['decimal_point']
print 'ab', ab
print locale.localeconv()['decimal_point'].find(',')
print locale.localeconv()['mon_decimal_point'].find(',')
ac = locale.localeconv()['mon_decimal_point']
print 'ac', ac, len(ac)
print locale.localeconv()

k1, k1a, k2 are printed as 1034.56

Egon

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFKZNyaZRiDo9Iq4qIRAuqhAKCW3x7iDbrxUDp3M/qHabwbw92osQCgi6N2
mmgb54LACmrd/Wi4BRi2iZo=
=psal
-----END PGP SIGNATURE-----


From piet at cs.uu.nl  Mon Jul 20 17:23:25 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 20 Jul 2009 23:23:25 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
Message-ID: <m2fxcrnj5e.fsf@cs.uu.nl>

>>>>> Duncan Booth <duncan.booth at invalid.invalid> (DB) wrote:

>DB> Phillip B Oldham <phillip.oldham at gmail.com> wrote:
>>> This make a lot more sense to us, and follows the convention from
>>> other languages. It would also mean chaining methods to manipulate
>>> lists would be easier:
>>> 
>>>>>> x = [2,1,3]
>>>>>> print x.sort()[0]
>>> 3
>>>>>> print x
>>> [2,1,3]

>DB> You already have a way to do what you want:

>>>>> x = [2,1,3]
>>>>> print sorted(x)[0]
>DB> 3

What kind of Python produces that?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From clp2 at rebertia.com  Mon Jul 20 17:30:16 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 20 Jul 2009 14:30:16 -0700
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <m2fxcrnj5e.fsf@cs.uu.nl>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
Message-ID: <50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>

On Mon, Jul 20, 2009 at 2:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Duncan Booth <duncan.booth at invalid.invalid> (DB) wrote:
>
>>DB> Phillip B Oldham <phillip.oldham at gmail.com> wrote:
>>>> This make a lot more sense to us, and follows the convention from
>>>> other languages. It would also mean chaining methods to manipulate
>>>> lists would be easier:
>>>>
>>>>>>> x = [2,1,3]
>>>>>>> print x.sort()[0]
>>>> 3
>>>>>>> print x
>>>> [2,1,3]
>
>>DB> You already have a way to do what you want:
>
>>>>>> x = [2,1,3]
>>>>>> print sorted(x)[0]
>>DB> 3
>
> What kind of Python produces that?

Assuming you're referring to the latter example, it was added in version 2.4
If you meant the former example, I think that's purely pseudo-Python.

Cheers,
Chris
-- 
http://blog.rebertia.com


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 17:38:22 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 18:38:22 -0300
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
Message-ID: <op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 20 Jul 2009 14:44:16 -0300, Francesco Bochicchio  
<bieffe62 at gmail.com> escribi?:

> On Jul 20, 6:22?pm, Esmail <ebo... at hotmail.com> wrote:
>> Hello all,
>>
>> I am trying to store a function and some associated information in an
>> object so that I can later have series of functions in a list that I can
>> evaluate one at a time.
>>
>> Right now I am only storing the function itself, the number of
>> arguments it expects and its string representation. I may add other
>> information such as the acceptable range for the parameters or other
>> characteristics such as maximum or minimum.
>>
>> I wonder if anyone could comment on my implementation and offer
>> suggestions or constructive criticisms?
>>
>> The 'loading' of the functions is a bit tedious and of course care
>> has to be taken to make sure the string representation corresponds to
>> the actual function computed. It would be nice if there was an
>> automatic way to convert the function to its string representation.
>>
>> Comments or problems with the approach I have taken?
>>
>> Thanks,
>> Esmail
>>
>> --
>>
>> #!/usr/bin/env python
>>
>> #
>> # store and represent functions
>> #
>>
>> import math
>>
>> class FunctionException(Exception):
>> ? ? ?""" custom exception """
>> ? ? ?def __init__(self, value):
>> ? ? ? ? ?self.parameter = value
>>
>> ? ? ?def __str__(self):
>> ? ? ? ? ?return repr(self.parameter)
>>
>> class Function(object):
>> ? ? ?""" class to represent a function """
>>
>> ? ? ?def __init__(self, fn, fn_str, num_vars):
>> ? ? ? ? ?"""
>> ? ? ? ? ?the function, its string representation, and the number of  
>> variables
>> ? ? ? ? ?"""
>> ? ? ? ? ?self.fn = fn
>> ? ? ? ? ?self.fn_str = fn_str
>> ? ? ? ? ?self.num_vars = num_vars
>>
>> ? ? ?def eval_fn(self, variables):
>> ? ? ? ? ?""" size of variables should equal num_vars .. else problem """
>> ? ? ? ? ?if len(variables) == self.num_vars:
>> ? ? ? ? ? ? ?result = self.fn(*variables)
>> ? ? ? ? ? ? ?return result
>> ? ? ? ? ?else:
>> ? ? ? ? ? ? ?raise FunctionException('invalid number of args provided -  
>> '+
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?'received %d, expected %d'
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?%(len(variables), self.num_vars))
>>
>> ? ? ?def str(self):
>> ? ? ? ? ?""" return string representation of function """
>> ? ? ? ? ?return self.fn_str
>>
>> def funct1(x):
>> ? ? ?''' small test function '''
>> ? ? ?return x * x
>>
>> def funct2(x, y):
>> ? ? ?''' small test function '''
>> ? ? ?return x + y
>>
>> def funct3(x):
>> ? ? ?''' small test function '''
>> ? ? ?return 1000 + (x*x + x) * math.cos(x)
>>
>> def main():
>> ? ? ?""" main method """
>> ? ? ?print 'in main'
>>
>> ? ? ?fn1 = Function(funct1, 'x * x', 1)
>> ? ? ?fn2 = Function(funct2, 'x + y', 2)
>> ? ? ?fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)
>>
>> ? ? ?for i in range(-10, 10):
>> ? ? ? ? ?try:
>>
>> ? ? ? ? ? ? ?print 'f(', [i],') =',
>> ? ? ? ? ? ? ?print fn3.str(), ' => ',
>> ? ? ? ? ? ? ?print fn3.eval_fn([i])
>>
>> ? ? ? ? ?except FunctionException, (ex):
>> ? ? ? ? ? ? ?print ex.parameter
>>
>> if __name__ == '__main__':
>> ? ? ?main()
>
>
> I can offer some small suggestions: it is up to you to evaluate if
> they make sense for your app:
>
> 1. use __doc__ function standard attribute for function description
> (your fn_str); this meanst that
>    you do not need fm_str in the constructor and you have to do e.g. :
>
> def funct2(x, y):
>       ''' x + y '''
>       return x + y
>
> then funct2.__doc__  becomes the string you want to associate to the
> function
>
> 2. Use __call__ instead of eval_fn : this way, the instance of your
> Function became a 'callable' and can be used
>    everywhere a function is needed. You can do:
>
>    f = Function(...)
>    f( some_args )
>
> 3. If you call a python function with wrong number of arguments, it
> already raises a TypeError exception which contains
>    - with different wording - the same information of your
> FunctionException : consider removing the check and using the
>    python error instead

If you follow the above suggestions, you'll see that your Function class  
becomes almost useless: a normal function already IS an object, so you  
don't have to wrap it inside ANOTHER object unless you need very special  
features.

-- 
Gabriel Genellina



From aahz at pythoncraft.com  Mon Jul 20 17:40:05 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 14:40:05 -0700
Subject: any suggestions to synchronize typed text and speech ?
References: <mailman.3406.1248034495.8015.python-list@python.org>
	<h40adj$bv6$1@adenine.netfront.net>
	<mailman.3419.1248082444.8015.python-list@python.org>
Message-ID: <h42o7l$bsp$1@panix3.panix.com>

In article <mailman.3419.1248082444.8015.python-list at python.org>,
Stef Mientki  <stef.mientki at gmail.com> wrote:
>
>I was afraid of that too, so I dropped the question in several places,
>and the writer of Scintilla himself came with the perfect answer.

...which was?...
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 17:40:14 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 18:40:14 -0300
Subject: Auto-generate GUI from a database table structure
References: <55660F9659966544BBA3AE14CE5D278D01243B8E04@exgtmb08.nam.nsroot.net>
Message-ID: <op.uxdyhcvlx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 20 Jul 2009 12:09:47 -0300, Boyd, Craig1  <craig1.boyd at citi.com>  
escribi?:

> I am trying to write a couple screens to update three or four database  
> tables on Oracle 10g and I was wondering if there was a way to  
> automatically generate some kind of GUI shell based on the tables that I  
> could then fill in with the logic / functionality I need.

I've never actually used it, but the DABO project seems to provide what  
you want: http://dabodev.com/

-- 
Gabriel Genellina



From marduk at letterboxes.org  Mon Jul 20 17:40:19 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Mon, 20 Jul 2009 17:40:19 -0400
Subject: How to import pydoc and then use it?
In-Reply-To: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>
References: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>
Message-ID: <1248126024.9281.3.camel@centar>

On Mon, 2009-07-20 at 13:38 -0700, mrstevegross wrote:
> I know how to use pydoc from the command line. However, because of
> complicated environmental setup, it would be preferable to run it
> within a python script as a native API call. That is, my python runner
> looks a bit like this:
> 
>   import pydoc
>   pydoc.generate_html_docs_for(someFile)
> 
> However, it's not clear to me from the pydoc documentation which
> function calls I need to use to make this behavior work. Any ideas?

Did you try 'pydoc pydoc'? ;)

>>> import pydoc
>>> htmldoc = pydoc.HTMLDoc()
>>> htmldoc_for_pydoc = htmldoc(pydoc)
>>> print htmldoc_for_pydoc



From p.f.moore at gmail.com  Mon Jul 20 17:40:58 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Mon, 20 Jul 2009 22:40:58 +0100
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>
Message-ID: <79990c6b0907201440r5470c486j207440183514ba9@mail.gmail.com>

2009/7/20 Chris Rebert <clp2 at rebertia.com>:
> On Mon, Jul 20, 2009 at 2:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>>> x = [2,1,3]
>>>>>>> print sorted(x)[0]
>>>DB> 3
>>
>> What kind of Python produces that?
>
> Assuming you're referring to the latter example, it was added in version 2.4
> If you meant the former example, I think that's purely pseudo-Python.

I think he was referring to the fact that the result should be 1, not 3.

Paul.


From malaclypse2 at gmail.com  Mon Jul 20 17:59:08 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Mon, 20 Jul 2009 17:59:08 -0400
Subject: locale doesn' format
In-Reply-To: <4A64DC9A.3060606@nord-com.net>
References: <4A64DC9A.3060606@nord-com.net>
Message-ID: <16651e80907201459w5060ad3ex9706a1f4ec12c@mail.gmail.com>

On Mon, Jul 20, 2009 at 5:07 PM, Egon Frerich<egon.frerich at nord-com.net> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> I want to format values to the german form eg. 1.034,56 but
> locale.format() doesn't work for me.
>
> Here is a little test program:
...
> k1 = locale.format_string('%12s',k,True)

I don't think you want to be using '%s' to format numbers in your
format strings.  Instead, use '%f' to format floating point values.

As I understand it, a %s in a format string actually calls str() on
the object that you pass into the formatting function, and I don't
think that floats (or Decimal.Decimal objects) take locale into
account when you do that.

-- 
Jerry


From FSet.SLB at gmail.com  Mon Jul 20 18:07:58 2009
From: FSet.SLB at gmail.com (Scott Burson)
Date: Mon, 20 Jul 2009 15:07:58 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>

On Jul 19, 11:31?am, Frank Buss <f... at frank-buss.de> wrote:
> I don't know of a free modern and stable Lisp implementation with
> mulithreading support for Windows, with a licence with which you can use it
> in closed source commercial programs

Have you looked at ECL?

http://ecls.sourceforge.net/

I've used it only a little, so I can't vouch for its stability, but it
fits the threading and license requirements (well, some corporate
lawyers have trouble with the LGPL, but I think it's usable).

-- Scott


From corbet at lwn.net  Mon Jul 20 18:16:59 2009
From: corbet at lwn.net (Jonathan Corbet)
Date: Mon, 20 Jul 2009 16:16:59 -0600
Subject: Python Essential Reference, 4th Edition - Now Available!
In-Reply-To: <EC84D091-DABA-49B3-A141-15E753A815EA@dabeaz.com>
References: <EC84D091-DABA-49B3-A141-15E753A815EA@dabeaz.com>
Message-ID: <20090720161659.78cbf90a@bike.lwn.net>

On Sun, 19 Jul 2009 11:03:05 -0500
David Beazley <dave at dabeaz.com> wrote:

> I'm pleased to announce the release of the Python Essential Reference,
> 4th edition, now available at a bookstore near you. More than a year
> in development, this edition covers Python 2.6, Python 3, and a wide
> variety of new library modules.

And here I am still using my old, dog-eared second edition...  Any
chance of getting a copy of the 4th for an LWN review?

Thanks,

jon
-- 
Jonathan Corbet / LWN.net / corbet at lwn.net


From hniksic at xemacs.org  Mon Jul 20 18:19:36 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 21 Jul 2009 00:19:36 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <87ljmjyp3b.fsf@busola.homelinux.net>

Phillip B Oldham <phillip.oldham at gmail.com> writes:

> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>> The main reason why you need both lists and tuples is that because a tuple
>> of immutable objects is itself immutable you can use it as a dictionary
>> key.
>
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.

An application visiting files on a filesystem recursively needs a
dictionary or set keyed by (st_dev, st_ino) to make sure it doesn't
visit the same file twice.  Memoization implementation (of a cache for
results of function application) might need to use a dictionary to map
function arguments, a tuple, to the function result.


From hniksic at xemacs.org  Mon Jul 20 18:20:53 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 21 Jul 2009 00:20:53 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<mailman.3441.1248125420.8015.python-list@python.org>
Message-ID: <87hbx7yp16.fsf@busola.homelinux.net>

Chris Rebert <clp2 at rebertia.com> writes:

>>>>>>> x = [2,1,3]
>>>>>>> print sorted(x)[0]
>>>DB> 3
>>
>> What kind of Python produces that?
>
> Assuming you're referring to the latter example, it was added in version 2.4
> If you meant the former example, I think that's purely pseudo-Python.

sorted([2, 1, 3])[0] evaluates to 1, not 3.


From http  Mon Jul 20 18:22:20 2009
From: http (Paul Rubin)
Date: 20 Jul 2009 15:22:20 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
	<7xljmjguxb.fsf@ruckus.brouhaha.com>
	<7a04b07d-2dea-455f-bafd-33461ce25a1a@q11g2000yqi.googlegroups.com>
Message-ID: <7xiqhn0zc3.fsf@ruckus.brouhaha.com>

vippstar <vippstar at gmail.com> writes:
> > I don't see how to implement such a thing in my code,
> Write a function:
> 
>   (if (< x y)
>       ValueError
>       (/ x y))

I meant changing the behavior of integer division in python.

> Wouldn't that mean 3/2 would also evaluate to ValueError?

Yes, the idea was that one can take the view that integer division
should not be allowed except through a 'div' function or some such.


From ethan at stoneleaf.us  Mon Jul 20 18:34:28 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Mon, 20 Jul 2009 15:34:28 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <24543805.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>	<4A5DE5E7.5070003@mrabarnett.plus.com>
	<24543805.post@talk.nabble.com>
Message-ID: <4A64F0F4.9060201@stoneleaf.us>

[fixed for bottom-posting]

Dr. Phillip M. Feldman wrote:
> MRAB-2 wrote:
> 
>>
>><snip>
>>
>>What values should 'xor' return? IMHO, if only one of the values is true
>>then it should return that value, otherwise it should return False.
>>
>>     1 xor 0 => 1
>>     0 xor 2 => 2
>>     1 xor 2 => False
>>     0 xor 0 => False
>>
>>This is because it's a Boolean operator, so it should fall back to
>>Boolean values when necessary, like 'not':
>>
>>     not 0 => True
>>     not 1 => False
>>
>>Also:
>>
>>     x and y and z => (x and y) and z
>>     x or y or z => (x or y) or z
>>
>>therefore:
>>
>>     x xor y xor z => (x xor y) xor z
>>
 > Suppose that 'xor' returns the value that is true when only one value is
 > true, and False otherwise.  This definition of xor doesn't have the 
standard
 > associative property, that is,
 >
 > (a xor b) xor c
 >
 > will not necessarily equal
 >
 > a xor (b xor c)
 >
 > To see that this is the case, let a= 1, b= 2, and c= 3.
 >
 > (a xor b) xor c
 >
 > yields 3, while
 >
 > a xor (b xor c)
 >
 > yields 1.  So, I'd prefer an xor operator that simply returns True or 
False.
 >
 > Phillip
 >

You are, of course, free to write your version however it makes sense to 
you and your team.  :)

Since the 'and' and 'or' already return objects (and objects evaluate to 
true or false), then 'xor' should behave likewise, IMO.  I expect that 
would be the case if it were ever added to the language.

~Ethan~


From martin at v.loewis.de  Mon Jul 20 18:39:11 2009
From: martin at v.loewis.de (=?UTF-8?B?Ik1hcnRpbiB2LiBMw7Z3aXMi?=)
Date: Tue, 21 Jul 2009 00:39:11 +0200
Subject: Compilation problem with Python < 2.6 and db >= 4.7
In-Reply-To: <mailman.3436.1248114395.8015.python-list@python.org>
References: <mailman.3436.1248114395.8015.python-list@python.org>
Message-ID: <4a64f210$0$8379$9b622d9e@news.freenet.de>

> Is there a way to make the bsddb module compile against db>=4.7 for python < 2.6
> (2.4.6, 2.5.4)?

I don't think so, no.

> I didn't find something on it.

If you don't want to use pybsddb either, for fear of incompatible API,
your only choice is to port _bsddb.c to the newer db versions. BSDDB
is in the tradition of both breaking the data format and the API
frequently, so we (python-dev) have given up on it.

Regards,
Martin


From niels.ellegaard at gmail.com  Mon Jul 20 18:39:24 2009
From: niels.ellegaard at gmail.com (Niels L. Ellegaard)
Date: Tue, 21 Jul 2009 00:39:24 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <86skgr0yjn.fsf@gmail.com>

Phillip B Oldham <phillip.oldham at gmail.com> writes:

> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.

If you just want a one-liner, and you don't care about speed you can
do the following (but I don't think this is considered best practice)

>>> x = [2,1,3]
>>> print list(sorted(x))   
[1, 2, 3]
>>> print x
[2, 1, 3]

     Niels


From vippstar at gmail.com  Mon Jul 20 18:48:51 2009
From: vippstar at gmail.com (vippstar)
Date: Mon, 20 Jul 2009 15:48:51 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com> 
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com> 
	<7xljmjguxb.fsf@ruckus.brouhaha.com>
	<7a04b07d-2dea-455f-bafd-33461ce25a1a@q11g2000yqi.googlegroups.com>
	<7xiqhn0zc3.fsf@ruckus.brouhaha.com>
Message-ID: <f524c9c4-70a5-4474-b0a7-56a20bd5e1a4@b14g2000yqd.googlegroups.com>

On Jul 21, 1:22?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> vippstar <vipps... at gmail.com> writes:
> > > I don't see how to implement such a thing in my code,
> > Write a function:
>
> > ? (if (< x y)
> > ? ? ? ValueError
> > ? ? ? (/ x y))
>
> I meant changing the behavior of integer division in python.
You'd either have to hack an implementation or change the standard (I
just noticed python doesn't have one).

> > Wouldn't that mean 3/2 would also evaluate to ValueError?
>
> Yes, the idea was that one can take the view that integer division
> should not be allowed except through a 'div' function or some such.
You brought up 3/2 == ValueError as a more appropriate value for the
integer division to evaluate, rather than 0. I thought you meant
specifically those kinds of divisions.


From kiorky at cryptelium.net  Mon Jul 20 18:51:42 2009
From: kiorky at cryptelium.net (kiorky)
Date: Tue, 21 Jul 2009 00:51:42 +0200
Subject: Compilation problem with Python < 2.6 and db >= 4.7
In-Reply-To: <4a64f210$0$8379$9b622d9e@news.freenet.de>
References: <mailman.3436.1248114395.8015.python-list@python.org>
	<4a64f210$0$8379$9b622d9e@news.freenet.de>
Message-ID: <4A64F4FE.805@cryptelium.net>

Martin v. L?wis a ?crit :
>> Is there a way to make the bsddb module compile against db>=4.7 for python < 2.6
>> (2.4.6, 2.5.4)?
> 
> I don't think so, no.
> 
>> I didn't find something on it.
> 
> If you don't want to use pybsddb either, for fear of incompatible API,
> your only choice is to port _bsddb.c to the newer db versions. BSDDB
> is in the tradition of both breaking the data format and the API
> frequently, so we (python-dev) have given up on it.

Yup, i understand.
I will be lazy and fall back as all packaging systems do, and keep in the
minitage packages tree both db versions.
Thanks for confirmation.

> 
> Regards,
> Martin


-- 
--
Cordialement,
KiOrKY
GPG Key FingerPrint: 0x1A1194B7681112AF




From lists at cheimes.de  Mon Jul 20 18:56:12 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 21 Jul 2009 00:56:12 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <86skgr0yjn.fsf@gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86skgr0yjn.fsf@gmail.com>
Message-ID: <h42smc$qhg$1@ger.gmane.org>

Niels L. Ellegaard wrote:
> Phillip B Oldham <phillip.oldham at gmail.com> writes:
> 
>> We often find we need to do manipulations like the above without
>> changing the order of the original list, and languages like JS allow
>> this. We can't work out how to do this in python though, other than
>> duplicating the list, sorting, reversing, then discarding.
> 
> If you just want a one-liner, and you don't care about speed you can
> do the following (but I don't think this is considered best practice)

sorted() already returns a new list not a generator as you might assume.

Christian



From piet at cs.uu.nl  Mon Jul 20 19:41:16 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 01:41:16 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>
	<mailman.3443.1248126067.8015.python-list@python.org>
Message-ID: <m2ws62ncrn.fsf@cs.uu.nl>

>>>>> Paul Moore <p.f.moore at gmail.com> (PM) wrote:

>PM> 2009/7/20 Chris Rebert <clp2 at rebertia.com>:
>>> On Mon, Jul 20, 2009 at 2:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>>>>> x = [2,1,3]
>>>>>>>>> print sorted(x)[0]
>DB> 3
>>>> 
>>>> What kind of Python produces that?
>>> 
>>> Assuming you're referring to the latter example, it was added in version 2.4
>>> If you meant the former example, I think that's purely pseudo-Python.

>PM> I think he was referring to the fact that the result should be 1, not 3.

The underlying thought was that you should copy and paste examples from
a real Python interpreter.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Mon Jul 20 20:10:55 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 17:10:55 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
	<mailman.3433.1248109750.8015.python-list@python.org>
Message-ID: <h4312f$307$1@panix3.panix.com>

In article <mailman.3433.1248109750.8015.python-list at python.org>,
D'Arcy J.M. Cain <darcy at druid.net> wrote:
>On 20 Jul 2009 09:00:33 -0700
>aahz at pythoncraft.com (Aahz) wrote:
>>
>> Out of curiosity, are there any JavaScript toolkits that generate code
>> that degrades gracefully when JavaScript is disabled?
>
>I understand what you want but I can't see how a toolkit can do that.
>How do you program "graceful?"  It seems pretty application specific.

Presumably the JS toolkit generates both code and HTML.  Actions that
normally get executed by JS should degrade to plain HTML links and form
submits (or possibly not display at all if it's a pure convenience).
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From gdamjan at gmail.com  Mon Jul 20 20:33:39 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Tue, 21 Jul 2009 02:33:39 +0200
Subject: locale doesn' format
References: <mailman.3440.1248124811.8015.python-list@python.org>
Message-ID: <30ffj6-qd6.ln1@archaeopteryx.softver.org.mk>

> I want to format values to the german form eg. 1.034,56 but
> locale.format() doesn't work for me.

seems to work here


>>> import decimal, locale
>>> locale.setlocale(locale.LC_ALL, 'mk_MK.UTF-8')
'mk_MK.UTF-8'
>>> locale.localeconv()['grouping']
[3, 3, 0]
>>> locale.localeconv()['thousands_sep']
' '
>>> locale.localeconv()['decimal_point']
','
>>> locale.format('%f', 1034.56,True)
'1 034,560000'
>>> locale.format('%d', 1034.56,True)
'1 034'



ps.
you can copy/paste the above in .txt file and then run/test it with:
python -m doctest -v  check.txt


-- 
?????? ( http://softver.org.mk/damjan/ )

  Begin...the rest is easy.



From gdamjan at gmail.com  Mon Jul 20 20:44:38 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Tue, 21 Jul 2009 02:44:38 +0200
Subject: locale doesn' format
References: <mailman.3440.1248124811.8015.python-list@python.org>
	<30ffj6-qd6.ln1@archaeopteryx.softver.org.mk>
Message-ID: <mkffj6-1f6.ln1@archaeopteryx.softver.org.mk>



>> I want to format values to the german form eg. 1.034,56 but
>> locale.format() doesn't work for me.
> 
> seems to work here

In 2.6 this is good too:

>>> import decimal, locale
>>> locale.setlocale(locale.LC_ALL, 'mk_MK.UTF-8')
>>> '{0:n}'.format(1234.56)
'1 234,56'


-- 
?????? ( http://softver.org.mk/damjan/ )

A: Because it reverses the logical flow of conversation.
Q: Why is top posting frowned upon?



From davea at ieee.org  Mon Jul 20 20:47:56 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 20 Jul 2009 20:47:56 -0400
Subject: Design question.
In-Reply-To: <68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>	<mailman.3423.1248095131.8015.python-list@python.org>
	<68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
Message-ID: <4A65103C.4010401@ieee.org>

Lacrima wrote:
> On Jul 20, 4:05 pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
> wrote:
>   
>> Lacrima wrote:
>>     
>>> Hello!
>>>       
>>> I am newbie in python and I have really simple question, but I need
>>> your advice to know how to do best.
>>> I need to store a number of dictionaries in certain place. I've
>>> decided to store them in a separate module.
>>> Like this:
>>> dicts.py
>>> -----------------------
>>> dict1 =....}
>>> dict2 =....}
>>> dict3 =....}
>>>       
>>> Then, when I need any dictionary, I can access it:
>>> import dicts
>>> dicts.dict1
>>>       
>> <snip>
> Hi, Jean-Michel!
>
> Thanks for your answer.
> I am not going to have names like dicts.py and dict1,dict2. That was
> just example. I wanted to know if it is correct to have dictionaries
> on a module level. Now I know that this is correct. I want to collect
> in one module a number of dictionaries, every of which describes a
> separate web service. And my function in another module will import
> required dictionary, depending on what web service should be used.
> Thanks again for the help.
>
> With regards,
> Max.
> (sorry if my English isn't very proper)
>
>   
It makes a lot of sense to store several dictionaries in a module, if 
they describe parallel things, or alternate ways of accessing something 
(like web services).

However, you might want to consider how they'll be accessed.  If another 
module is going to "import required dictionary," then you have some 
means of selection.  Perhaps that selection should be in the same 
module, or at least the data structure to select it should be in the 
same module.

Let's say you have four choices right now.  And you add a fifth later.  
Do you want to have to edit both the "function in the other module" as 
well as this module?

This is similar to a feature that some programs have, "plug-ins."   
There a customer can add an additional runtime just by dropping a new 
.py file in the appropriate directory, and the program will find it and 
add it to its "list of features."

So I'm just suggesting you figure out how the program might evolve, and 
set up the data so changes may be localized, if practical.  This turns 
out usually to be parallel to the notion of naming things and grouping 
them by similarity of functionality.

DaveA




From sajmikins at gmail.com  Mon Jul 20 20:56:26 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Mon, 20 Jul 2009 17:56:26 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7xljmk8q1m.fsf@ruckus.brouhaha.com>
Message-ID: <6348dcb8-bfc1-446e-b7bf-28657e2b607e@j32g2000yqh.googlegroups.com>

On Jul 19, 2:51 pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Calroc <forman.si... at gmail.com> writes:
> > I'm engaged presently in starting a school to teach programming from
> > the ground up, based roughly on the curriculum outlined in the article
> > I mentioned. ...
> > I'm excited about formal methods because one, I just heard about them,
>
> Formal methods are a big and complicated subject.  Right after you
> heard about them is probably not the best time to start teaching them.
> Better get to understand them yourself first.

Very good point.

But I'm glad it's there to study, these are wheels I don't have to
invent for myself.

~Simon


From sajmikins at gmail.com  Mon Jul 20 20:57:05 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Mon, 20 Jul 2009 17:57:05 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7cimf0F27u23eU1@mid.individual.net>
Message-ID: <11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>

On Jul 20, 4:00 am, greg <g... at cosc.canterbury.ac.nz> wrote:
> Calroc wrote:
> > It may be that flawless software is an unreachable asymptote, like the
> > speed of light for matter, but I'm (recently!) convinced that it's a
> > goal worthy of exploration and effort.
>
> Seems to me that once you get beyond the toy program
> stage and try to apply correctness proving to real
> world programming problems, you run up against the
> problem of what exactly you mean by "correct".
>
> Once the requirements get beyond a certain level of
> complexity, deciding whether the specifications
> themselves are correct becomes just as difficult as
> deciding whether the program meets them.

I agree.  You could prove that a game renders geometry without
crashing, but not that it's fun.  Or in an accounting package you
could prove that it never loses a cent in tracking accounts and
payments, or that its graph-rendering code does correctly render data
(without introducing artifacts, for instance), but not that it will
let you notice trends.

> Then there's the fact that very often we don't
> even know what the exact requirements are, and it's
> only by trying to write and use the program that
> we discover what they really are -- or at least,
> get a better idea of what they are, because the
> process is usually iterative, with no clear end
> point.

Aye, if you're still exploring your solution space your requirements
are perforce somewhat nebulous.

> So in theory, correctness proofs are a fine idea,
> and might even be doble on a small scale, but the
> real world is huge and messy!

Very true, but I think it is still worthy to build larger systems from
proven components combined in provably correct ways, at least to the
extent possible.

> > Just because it's unattainable doesn't make it undesirable.  And who
> > knows? Maybe the horse will learn to sing.
>
> Striving to find ways of writing less bugs is a
> worthy goal, but I think of it more in terms of
> adopting patterns of thought and programming that
> make it more likely you will write code that does
> what you had in mind, rather than a separate
> "proof" process that you go through afterwards.

I would consider formal methods exactly "patterns of thought and
programming that make it more likely you will write code that does
what you had in mind", in fact that's why I'm excited about them.

My understanding (so far) is that you (hope to) /derive/ correct code
using formal logic, rather than writing code and then proving its
soundness.

The real win, IMO, is teaching computers as a logical, mathematical
activity (that can certainly depart for realms less rigorously
defined.)

I think anyone who can spontaneously solve a Sudoku puzzle has enough
native grasp of "formal" methods of reasoning to learn how to derive
working programs logically.  Making the formal methods explicit gives
you the strongest available confidence that you are reasoning, and
programming, correctly.

This is not to say that "incorrect" (or unproven or unprovable)
programs are never useful or necessary.  However, I do feel that it's
better to learn the "correct" way, and then introduce ambiguity, than
to simply throw e.g. Java at some poor student and let them find solid
ground "catch as catch can".


~Simon



From darcy at druid.net  Mon Jul 20 21:18:28 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Mon, 20 Jul 2009 21:18:28 -0400
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
In-Reply-To: <h4312f$307$1@panix3.panix.com>
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
	<mailman.3433.1248109750.8015.python-list@python.org>
	<h4312f$307$1@panix3.panix.com>
Message-ID: <20090720211828.88876711.darcy@druid.net>

On 20 Jul 2009 17:10:55 -0700
aahz at pythoncraft.com (Aahz) wrote:
> >I understand what you want but I can't see how a toolkit can do that.
> >How do you program "graceful?"  It seems pretty application specific.
> 
> Presumably the JS toolkit generates both code and HTML.  Actions that
> normally get executed by JS should degrade to plain HTML links and form
> submits (or possibly not display at all if it's a pure convenience).

As I said, I do understand what you are after but I still think it is a
judgement call.  What defines "convenience?"  How does the library know
what is essential and what is pretty?

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From ebonak at hotmail.com  Mon Jul 20 21:53:59 2009
From: ebonak at hotmail.com (Esmail)
Date: Mon, 20 Jul 2009 21:53:59 -0400
Subject: comments? storing a function in an object
In-Reply-To: <op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
References: <mailman.3430.1248106983.8015.python-list@python.org>	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
	<op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A651FB7.1030602@hotmail.com>

Gabriel Genellina wrote:
 >
> If you follow the above suggestions, you'll see that your Function class 
> becomes almost useless: a normal function already IS an object, so you 
> don't have to wrap it inside ANOTHER object unless you need very special 
> features.

Hello Gabriel,

In general I would agree with you, but in my specific case
I want so store some additional meta-data with each function, such
as the valid range for input values, where the max or minimum are located,
the name/source for the function etc. I am creating list of functions
for use in testing optimization code, so it seems best to store this
data along with the function I am going to optimize in order to verify
the results for a given range (for instance).

Esmail




From http  Mon Jul 20 21:54:54 2009
From: http (Paul Rubin)
Date: 20 Jul 2009 18:54:54 -0700
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7xljmk8q1m.fsf@ruckus.brouhaha.com>
	<6348dcb8-bfc1-446e-b7bf-28657e2b607e@j32g2000yqh.googlegroups.com>
Message-ID: <7xws627qc1.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> But I'm glad it's there to study, these are wheels I don't have to
> invent for myself.

http://dwheeler.com/essays/high-assurance-floss.html

might be an interesting place to start.


From ebonak at hotmail.com  Mon Jul 20 22:01:45 2009
From: ebonak at hotmail.com (Esmail)
Date: Mon, 20 Jul 2009 22:01:45 -0400
Subject: comments? storing a function in an object
In-Reply-To: <3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
Message-ID: <4A652189.2000607@hotmail.com>

Hi Francesco,

Those were great suggestions!

Re 1: I used the __doc__ attribute to eliminate the parameter in the
       constructor as you suggested. Also, much easier to specify the
       character string with the actual function than later to match it
       up like I was.

class Function(object):
     """ class to represent a function """

     def __init__(self, fn, num_vars):
         """ the function, its string representation, and the number of 
variables """
         self.fn = fn
         self.fn_str = fn.__doc__
         self.num_vars = num_vars


Re 2: I will need to read up on __call__ to see how to use it here ..


Re 3: I think I still need to have my own exception handler as I am
       using the 'extended call syntax' now (I just learned about this
       yesterday) and I will always just supply one argument, the
       list. Or perhaps my custom exception will be superfluous once I
       figure out __call__ ..?


Thank you for taking the time to help, always good to learn new things.

Esmail



From aahz at pythoncraft.com  Mon Jul 20 22:53:08 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 19:53:08 -0700
Subject: are user defined classes hashable?
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net>
	<mailman.3396.1248018412.8015.python-list@python.org>
	<373d6c69-6965-4a88-bdd2-8028ef850bf8@k6g2000yqn.googlegroups.com>
Message-ID: <h43aik$oct$1@panix3.panix.com>

In article <373d6c69-6965-4a88-bdd2-8028ef850bf8 at k6g2000yqn.googlegroups.com>,
Hyuga  <hyugaricdeau at gmail.com> wrote:
>
>Regardless, Nicolas's example can be applied to the class too:
>
>>>> class Foo(object):
>	pass
>
>>>> hash(Foo)
>11443104
>>>> id(Foo)
>11443104
>
>class objects are just objects of type 'type'.

Not quite.  They certainly default that way, but changing the metaclass
changes a class's type::

class M(type): 
    pass

class C(object): 
    pass

class C2(object):
    __metaclass__ = M

print type(C)
print type(C2)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From pavlovevidence at gmail.com  Mon Jul 20 23:53:53 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 20 Jul 2009 20:53:53 -0700 (PDT)
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
Message-ID: <f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com>

On Jul 20, 9:22?am, Esmail <ebo... at hotmail.com> wrote:
> def funct1(x):
> ? ? ?''' small test function '''
> ? ? ?return x * x
>
> def funct2(x, y):
> ? ? ?''' small test function '''
> ? ? ?return x + y
>
> def funct3(x):
> ? ? ?''' small test function '''
> ? ? ?return 1000 + (x*x + x) * math.cos(x)
>
> def main():
> ? ? ?""" main method """
> ? ? ?print 'in main'
>
> ? ? ?fn1 = Function(funct1, 'x * x', 1)
> ? ? ?fn2 = Function(funct2, 'x + y', 2)
> ? ? ?fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)


If you are defining all of the functions are in-line like this (and I
assume you are because you seem to need a function object), I'd just
exec the string representation.  This is to support the DRY
principle.  You could do something like this:


class Function(object):
    def __init__(self,args,body):
        ns = {}
        exec '''def func(%s): return %s''' in ns
        self.fn = ns['func']
        self.fn_str = body
        self.num_vars = args.count(',')+1


You have to be REALLY REALLY careful not to pass any user-supplied
data to it if this is a server running on your computer, of course.
(If it's an application running on the user's computer it doesn't
matter.)

Still wouldn't be a bad idea to pass it through some kind of validator
for extra protection.


Carl Banks


From boyd.blackwell at gmail.com  Mon Jul 20 23:56:51 2009
From: boyd.blackwell at gmail.com (bdb112)
Date: Mon, 20 Jul 2009 20:56:51 -0700 (PDT)
Subject: clean way prepend an element to a numpy array
Message-ID: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>

If I want to add an element at the beginning of an array, it seems
like I must make a list, insert in place, then make an array again.

Of course, lists can be efficient too, and the insert() funtion works
nicely in that case, but sometimes arrays are the best choice

e.g.
x=array([1,2,3])
# to put the element 0 at the head of the array
listx=list(x)
listx.insert(0,0)
x=array(listx)
# this extra effort distracts from the clarity of the code, and must
slow things a little.

# While I appreciate that array operations that cause memory re-
allocation and copying are to be
#  avoided if at all possible, sometimes this is the best compromise
between clarity and efficiency

# A nicer piece of code would be

x.insert(0,0)
#or
x.prepend(0)

# It is a little easier to grow an array at the end (if it is not
referenced)
x.resize(4)

I saw this interest syntax on this site
x[:0]=0

I guess that is cute, but could be confusing....(and doesn't work)


From ben+python at benfinney.id.au  Tue Jul 21 00:13:55 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 21 Jul 2009 14:13:55 +1000
Subject: clean way prepend an element to a numpy array
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
Message-ID: <87eisaad18.fsf@benfinney.id.au>

bdb112 <boyd.blackwell at gmail.com> writes:

> If I want to add an element at the beginning of an array, it seems
> like I must make a list, insert in place, then make an array again.

The NumPy ?ndarray? type (which is what you get by default from the
?array? factory function) is a far more complex type than (and is not
derived from) the Python list.

For manipulating them, you'll want to study the NumPy documentation
<URL:http://docs.scipy.org/doc/numpy/reference/arrays.ndarray.html>.

-- 
 \     ?Are you pondering what I'm pondering?? ?I think so, Brain, but |
  `\        I don't think Kay Ballard's in the union.? ?_Pinky and The |
_o__)                                                           Brain_ |
Ben Finney


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 00:31:04 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 01:31:04 -0300
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
	<op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
	<4A651FB7.1030602@hotmail.com>
Message-ID: <op.uxehh2rox6zn5v@gabriel.cpe.telecentro.net.ar>

En Mon, 20 Jul 2009 22:53:59 -0300, Esmail <ebonak at hotmail.com> escribi?:

> Gabriel Genellina wrote:
>  >
>> If you follow the above suggestions, you'll see that your Function  
>> class becomes almost useless: a normal function already IS an object,  
>> so you don't have to wrap it inside ANOTHER object unless you need very  
>> special features.
>
> Hello Gabriel,
>
> In general I would agree with you, but in my specific case
> I want so store some additional meta-data with each function, such
> as the valid range for input values, where the max or minimum are  
> located,
> the name/source for the function etc. I am creating list of functions
> for use in testing optimization code, so it seems best to store this
> data along with the function I am going to optimize in order to verify
> the results for a given range (for instance).

You can store all meta-data in the function itself:

py> def triangle(b, h):
...   "area of triangle: b*h/2"
...   return b*h/2
...
py> triangle.foo = "some value"
py> triangle.foo
'some value'

Python already knows some properties:

py> triangle.func_code.co_argcount
2
py> triangle.func_doc
'area of triangle: b*h/2'
py> triangle.__doc__
'area of triangle: b*h/2'

You may use this variant of Carl Banks proposal - this is a factory  
function that returns new function objects:

def inline_function_factory(name, args, expr):
   ns = {}
   exec '''def %s(%s):
             %r
             return %s''' % (
     name, args, expr, expr) in ns
   function = ns[name]
   return function

py> sqr = inline_function_factory("square", "x", "x*x")
py> sqr(3)
9
py> sqr.__doc__
'x*x'
py> sqr
<function square at 0x00B46770>

Wrapping a function object isn't necesarily bad, but perhaps you're doing  
things more complicated than should be.

-- 
Gabriel Genellina



From smolds at orcasoul.com  Tue Jul 21 00:33:25 2009
From: smolds at orcasoul.com (OrcaSoul)
Date: Mon, 20 Jul 2009 21:33:25 -0700 (PDT)
Subject: Mechanize not recognized by py2exe
In-Reply-To: <op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>
References: <4A60C81F.7080707@comcast.net>
	<op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <24581545.post@talk.nabble.com>



Gabriel Genellina-7 wrote:
> 
> En Fri, 17 Jul 2009 15:51:11 -0300, Stephen M. Olds <smolds at comcast.net>  
> escribi?:
> 
>> I have a Python script getData.py that uses Mechanize, and runs fine  
>> under the
>> interpreter. It was installed using easy_install - and the install  
>> seemed to
>> indicate it was completed.
>>
>> The problem is, when I try to compile it using py2exe while in the  
>> folder of the
>> script, and using the run line command:
>>
>> python getData.py py2exe
>>
>> I get the warning: "Import error: No Module named mechanize"...
>>
>> I checked the environmental path and find the following:
>> %SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program  
>> Files (x86)\Python;C:\Python25\Lib\site-packages;C:\Program
>> Files (x86)\Common Files\Adobe\AGL
> 
> The system PATH is irrelevant here - it's only used by Windows to locate  
> the Python executable. I don't see a reason to list  
> C:\Python25\Lib\site-packages here.
> You're mostly interested in sys.path instead (that is, the 'path'  
> attribute in the 'sys' Python module)
> 
>> I did a search for mechanize and find an egg file in  
>> C:\Python25\Lib\site-packages
>> named mechanize-0.1.7b-py2.5.
>>
>> Not really understanding the "egg" thing, what do I have here that needs  
>> to be
>> done?
> 
> I'm not an egg expert either, and I try to avoid them as a plague. But I  
> *think* you can delete the .egg and re-install it using easy_install with  
> the -Z option.
> 
> -- 
> Gabriel Genellina
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

Gabriel, that was the kick in the pants I needed! Thanks - after over a week
searching through the same 15 web pages these old eyes simply blurred over
and I missed that one...I had tried the -a option, but that's what got me
the eggs...

So, thanks for the help...it's too late to name my first born after you, but
I did have a cat named Gabriel - she was a great cat!

Stephen

-- 
View this message in context: http://www.nabble.com/Mechanize-not-recognized-by-py2exe-tp24540012p24581545.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From fb at frank-buss.de  Tue Jul 21 00:57:39 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 06:57:39 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
Message-ID: <61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>

Scott Burson wrote:

> Have you looked at ECL?
> 
> http://ecls.sourceforge.net/
> 
> I've used it only a little, so I can't vouch for its stability, but it
> fits the threading and license requirements (well, some corporate
> lawyers have trouble with the LGPL, but I think it's usable).

I didn't tried it myself, but looks like it is not very stable:

http://www.mail-archive.com/application-builder at lispniks.com/msg01069.html

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From astan.chee at al.com.au  Tue Jul 21 01:02:57 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 21 Jul 2009 15:02:57 +1000
Subject: ignore special characters in python regex
Message-ID: <4A654C01.2000508@al.com.au>

Hi,
I'm reading text from a file (per line) and I want to do a regex using 
these lines but I want the regex to ignore any special characters and 
treat them like normal strings.
Is there a regex function that can do this?
Here is what I have so far:
fp = open('file.txt','r')
notes = fp.readlines()
fp.close()
strin = "this is what I want"
for note in notes:
     if re.search(r""+ str(note) + "",strin):
           print "Found " + str(note) + " in " + strin

Thanks for any help


From fb at frank-buss.de  Tue Jul 21 01:08:41 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 07:08:41 +0200
Subject: any suggestions to synchronize typed text and speech ?
References: <mailman.3406.1248034495.8015.python-list@python.org>
Message-ID: <azifuk04513x$.1wmls13dctrxz$.dlg@40tude.net>

Stef Mientki wrote:

> Here the problem part:
> I need to synchronize the typed text with the sound during playback.
> So if I click somewhere in the sound recording,
> the line of text, typed that moment should be highlighted.
> And vise versa, if the cursor in the text is moved and some special key 
> is pressed,
> the sound starting 10 or 20seconds earlier should be playbacked.

You could use some screen recording tools, e.g.
http://www.techsmith.com/camtasia.asp on Windows. Most tools allows you to
record speech while recording the screen.

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From doomster at knuut.de  Tue Jul 21 01:16:10 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Tue, 21 Jul 2009 07:16:10 +0200
Subject: C-API, tp_dictoffset vs tp_members
Message-ID: <7cl194F28ojoqU1@mid.uni-berlin.de>

Hi!

When would I use PyObject_SetAttrString/tp_dictoffset instead of tp_members? 

I have a predefined set of members, some of which are optional. The problem 
I had with an embedded dictionary was that I can't see its elements using 
"dir()". Now I just converted to using tp_members, and it still seems to 
work correctly for the cases I tested. Even better, I can declare the fields 
as read-only then and add doc-strings. So, I wonder, what made the original 
author[2] use tp_dictoffset instead? 

In case you wonder, I'm looking at the Python bindings for GDB[1], file 
gdb/python/python-type.c, struct field_object.


Thanks!

Uli


[1] http://sourceware.org/gdb/wiki/PythonGdb
[2] Yes I could ask them, but I'd like to get an understanding of the pros 
and cons.




From fb at frank-buss.de  Tue Jul 21 01:18:01 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 07:18:01 +0200
Subject: ignore special characters in python regex
References: <mailman.3456.1248152587.8015.python-list@python.org>
Message-ID: <13459wwzhbzoo$.jei131n3o527.dlg@40tude.net>

Astan Chee wrote:

> I'm reading text from a file (per line) and I want to do a regex using 
> these lines but I want the regex to ignore any special characters and 
> treat them like normal strings.
> Is there a regex function that can do this?

Maybe re.escape helps?

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From boyd.blackwell at gmail.com  Tue Jul 21 01:41:13 2009
From: boyd.blackwell at gmail.com (bdb112)
Date: Mon, 20 Jul 2009 22:41:13 -0700 (PDT)
Subject: clean way prepend an element to a numpy array
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
	<87eisaad18.fsf@benfinney.id.au>
Message-ID: <608f857f-3925-44db-9e5e-8969b6a116af@b25g2000prb.googlegroups.com>

On Jul 21, 2:13?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> bdb112 <boyd.blackw... at gmail.com> writes:
> > If I want to add an element at the beginning of an array, it seems
> > like I must make a list, insert in place, then make an array again.
>
> The NumPy ?ndarray? type (which is what you get by default from the
> ?array? factory function) is a far more complex type than (and is not
> derived from) the Python list.
>
> For manipulating them, you'll want to study the NumPy documentation
> <URL:http://docs.scipy.org/doc/numpy/reference/arrays.ndarray.html>.
>

Yes, I had had a look through that - nothing there that allows writing
a succint
clear statement (except for my .resize example in the original post),
although if efficiency was
a concern, then maybe resize and shift right, but that would really
obscure the code.



From sjmachin at lexicon.net  Tue Jul 21 02:01:38 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 23:01:38 -0700 (PDT)
Subject: ignore special characters in python regex
References: <mailman.3456.1248152587.8015.python-list@python.org>
Message-ID: <ce9a527a-767f-481a-9a48-00492ae7a88f@g1g2000pra.googlegroups.com>

On Jul 21, 3:02?pm, Astan Chee <astan.c... at al.com.au> wrote:
> Hi,
> I'm reading text from a file (per line) and I want to do a regex using
> these lines but I want the regex to ignore any special characters and
> treat them like normal strings.
> Is there a regex function that can do this?

It would help if you were to say

(1) what "ignore ... characters" means -- pretend they don't exist?
(2) what are "special chararacters" -- non-alphanumeric?
(3) what "treat them like normal strings" means
(4) how you expect these special characters to be (a) ignored and (b)
"treated like normal strings" /at the same time/.

Cheers,
John


From cmpython at gmail.com  Tue Jul 21 02:11:33 2009
From: cmpython at gmail.com (Che M)
Date: Mon, 20 Jul 2009 23:11:33 -0700 (PDT)
Subject: any suggestions to synchronize typed text and speech ?
References: <mailman.3406.1248034495.8015.python-list@python.org>
Message-ID: <9eb00b5c-f51b-45ab-9e1a-1b1691a7e538@h18g2000yqj.googlegroups.com>

On Jul 19, 4:15?pm, Stef Mientki <stef.mien... at gmail.com> wrote:
> hello,
>
> I'm using Scintilla as a wxPython widget with great pleasure.
> I now have an application where I want to make notes during a conversation,
> but also want to record the speech during that conversation.
> I'm using Scintilla as a wxPython widget for editing and PyAudio for the
> speech recording,
> until so far everything works fine.
>
> Here the problem part:
> I need to synchronize the typed text with the sound during playback.
> So if I click somewhere in the sound recording,
> the line of text, typed that moment should be highlighted.
> And vise versa, if the cursor in the text is moved and some special key
> is pressed,
> the sound starting 10 or 20seconds earlier should be playbacked.
>
> I though of adding bookmarks (because these are fixed in the text), and
> keep a list of bookmarks and sound pointers.
> This idea should work, but there are only 31 bookmarks.
>
> Any other suggestions ?
>
> thanks,
> Stef Mientki

Stef, it occurs to me now that you might be useful to look at
Transana:
http://www.transana.org/

>From their site:

Transana is software for professional researchers who want to
analyze digital video or audio data. Transana lets you analyze
and manage your data in very sophisticated ways. Transcribe it,
identify analytically interesting clips, assign keywords to clips,
arrange and rearrange clips, create complex collections of
interrelated clips, explore relationships between applied keywords,
and share your analysis with colleagues.

It is written in Python, uses Scintilla, and is open source (GPL):
http://www.transana.org/developers/index.htm

Che


From ivlenin at gmail.com  Tue Jul 21 02:24:05 2009
From: ivlenin at gmail.com (I V)
Date: 21 Jul 2009 08:24:05 +0200
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
	<op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
	<mailman.3452.1248141246.8015.python-list@python.org>
Message-ID: <4a655f05$1@news.x-privat.org>

On Mon, 20 Jul 2009 21:53:59 -0400, Esmail wrote:
> In general I would agree with you, but in my specific case I want so
> store some additional meta-data with each function, such as the valid
> range for input values, where the max or minimum are located, the
> name/source for the function etc. I am creating list of functions for
> use in testing optimization code, so it seems best to store this data
> along with the function I am going to optimize in order to verify the
> results for a given range (for instance).

You can set attributes on functions, so if your class is just storing 
this data, rather than altering the behavior of the function, you may be 
able to just use a function:

def f(x, y):
	"x * y"
	return x * y

f.arguments_max = [1000, 255]

A function also already knows how many arguments it takes, which you can 
access as f.func_code.co_argcount


From jayshree06comp at gmail.com  Tue Jul 21 02:29:06 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Mon, 20 Jul 2009 23:29:06 -0700 (PDT)
Subject: python function for retrieving key and encryption
Message-ID: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>

M2Crypto package not showing the 'recipient_public_key.pem' file at
linux terminal .how do i get/connect with recipient public key.

exactly i need to check how can i open this file through linux
commands.

import M2Crypto def encrypt(): recip = M2Crypto.RSA.load_pub_key(open
('recipient_public_key.pem','rb').read()) print recip; plaintext =
whatever i need to encrypt msg = recip.public_encrypt
(plaintext,RSA.pkcs1_padding) print msg;

after calling the function its not giving any output and even any
error

i also tried as 'Will' said

pk = open('public_key.pem','rb').read() print pk; rsa =
M2Crypto.RSA.load_pub_key(pk)

whats the mistake i am not getting .will somebody help me out.
is something wrong in opening 'recipient_public_key.pem'. is M2Crypto
contain this file inbuilt .from where this file taking public key of
the recipient i'. what this file contain and how it will work .should
i need to create such a file for my purpose.if it is then how can i
create this  and how it will retrieve the key,where i recognize my
recipient to get his public key .is something like database at server.

please give me a quick response......
looking for your answer.


From jackdied at gmail.com  Tue Jul 21 02:42:02 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Tue, 21 Jul 2009 02:42:02 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <02746997$0$5185$c3e8da3@news.astraweb.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
	<mailman.3317.1247864411.8015.python-list@python.org>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
	<02746997$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <b8e622740907202342r5b0f7367h29fd62f4b15e3da0@mail.gmail.com>

On Mon, Jul 20, 2009 at 10:00 AM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Mon, 20 Jul 2009 09:34:24 +0000, Sion Arrowsmith wrote:
>
>> Terry Reedy ?<tjreedy at udel.edu> wrote:
>>>Sion Arrowsmith wrote:
>>>> Jack Diederich ?<jackdied at gmail.com> wrote:
>>>>> It isn't an OrderedDict thing, it is a comparison thing. ?Two regular
>>>>> dicts also raise an error if you try to LT them.
>>>> Python 2.5.2
>>>>>>> d1 = dict((str(i), i) for i in range (10)) d2 = dict((str(i), i)
>>>>>>> for i in range (20)) d1 < d2
>>>> True
>>>Try reversing the definitions of d1 and d2. The dicts are probably being
>>>compared by id (address), which is the 2.x CPython default.
>>
>> Like this?
>>
>>>>> d1 = dict((str(i), i) for i in range (20))
>>>>> d2 = dict((str(i), i) for i in range (10))
>>>>> d1 < d2
>> False
>>>>> id(d1) < id(d2)
>> True
>>
>> I didn't know that comparison for anything other than equality defaulted
>> to using id. That really is rather broken, and I'm glad 3.0 fixed it.
>
>
> I don't think comparisons other than equality use id. That would be
> rather insane. If anyone can demonstrate such comparisons in a built-in
> or standard library class, I'd like to see it.
>
>
> For the record, dicts have been comparable with < and > since at least
> Python 1.5:
>
> $ python1.5
> Python 1.5.2 (#1, Apr ?1 2009, 22:55:54) ?[GCC 4.1.2 20070925 (Red Hat
> 4.1.2-27)] on linux2
> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>>
>>>> {1: 'a', 2: 'b'} < {2: 'b', 3: 'a'}
> 1
>
>
> Reading the docs:
>
> http://docs.python.org/library/stdtypes.html#comparisons
> http://docs.python.org/library/stdtypes.html#mapping-types-dict
>
> I can only suggest that dicts compare in an arbitrary but consistent
> fashion.

I should have specified 3.x but since we were talking about
OrderedDicts (only in 3.1) I didn't say it explicitly.   Earlier
versions of python were very permissive with comparisons -- it was
rare that any cmp() raised an error and the ultimate fallback was on
the object's id.  This is one of the non-backwards compatible changes
in 3k.  Now comparing two of the same thing that don't have an obvious
ordering is an error.  Is a dict "greater than" if it has a larger
size?  if its max key is larger?  what does "max key" mean when the
keys aren't even comparable?.  Comparing things that aren't extremely
similar is an error now also.

-Jack


From astan.chee at al.com.au  Tue Jul 21 02:59:16 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 21 Jul 2009 16:59:16 +1000
Subject: ignore special characters in python regex
In-Reply-To: <ce9a527a-767f-481a-9a48-00492ae7a88f@g1g2000pra.googlegroups.com>
References: <mailman.3456.1248152587.8015.python-list@python.org>
	<ce9a527a-767f-481a-9a48-00492ae7a88f@g1g2000pra.googlegroups.com>
Message-ID: <4A656744.7050908@al.com.au>

I think the re.escape did the trick.
to answer your questions:
By "ignore" i meant instead of using non-alphanumeric characters that 
have special significance in regular expression (e.g. [|\]) and treat 
them as normal strings (i.e preceded by \), but since I don't know all 
the characters in regular expression that have special significance, I 
don't know which ones to add a '\' infront of.
Thanks anyway

John Machin wrote:
> On Jul 21, 3:02 pm, Astan Chee <astan.c... at al.com.au> wrote:
>   
>> Hi,
>> I'm reading text from a file (per line) and I want to do a regex using
>> these lines but I want the regex to ignore any special characters and
>> treat them like normal strings.
>> Is there a regex function that can do this?
>>     
>
> It would help if you were to say
>
> (1) what "ignore ... characters" means -- pretend they don't exist?
> (2) what are "special chararacters" -- non-alphanumeric?
> (3) what "treat them like normal strings" means
> (4) how you expect these special characters to be (a) ignored and (b)
> "treated like normal strings" /at the same time/.
>
> Cheers,
> John
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/10095d91/attachment.html>

From joswig at lisp.de  Tue Jul 21 03:00:16 2009
From: joswig at lisp.de (Rainer Joswig)
Date: Tue, 21 Jul 2009 00:00:16 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
	<61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>
Message-ID: <f2361d71-dd8b-45cc-89fc-edf39e57197a@24g2000yqm.googlegroups.com>

On 21 Jul., 06:57, Frank Buss <f... at frank-buss.de> wrote:
> Scott Burson wrote:
> > Have you looked at ECL?
>
> >http://ecls.sourceforge.net/
>
> > I've used it only a little, so I can't vouch for its stability, but it
> > fits the threading and license requirements (well, some corporate
> > lawyers have trouble with the LGPL, but I think it's usable).
>
> I didn't tried it myself, but looks like it is not very stable:
>
> http://www.mail-archive.com/application-buil... at lispniks.com/msg01069.html


I'm not sure if it is fair to post a reference to a single
post by someone without context and without having used ECL.
If there are stability problems, people can report to the
ECL mailing list. The maintainers are very active.

Frank, I have seen you constructive and posting code a year ago.
What happened? Several messages of yours I've seen here are now
going in the direction of been mostly useless. I thought
you could do better.

If you are no longer interested in Lisp with no first hand usage,
why not switch to comp.lang.misc or some other random place?


From hv at tbz-pariv.de  Tue Jul 21 03:03:23 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Tue, 21 Jul 2009 09:03:23 +0200
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <7cl7hrF28lsb2U1@mid.individual.net>

casebash schrieb:
> Hi,
> 
> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

Hi,

you could use a list of characters. It would not be difficult to
implement this as a class with all fancy methods like startswith() ...

  Thomas

-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From googler.1.webmaster at spamgourmet.com  Tue Jul 21 03:22:27 2009
From: googler.1.webmaster at spamgourmet.com (moerchendiser2k3)
Date: Tue, 21 Jul 2009 00:22:27 -0700 (PDT)
Subject: PIL for OSX 64bit
Message-ID: <e0564f03-f736-4d0f-8c50-e1bce0eb55f8@r2g2000yqm.googlegroups.com>

Hi,

I have a problem with Python and the Python Image Library to get it
work on OSX 64 bit. Maybe anyone can help me? I started Python in 64
bit mode and called Image.open(...).load() and got:

ImportError: The _imaging C module is not installed

Yes, it seems PIL is not available in 64 bit on my system, but I can't
compile it in any way. Is there a tutorial or something like that
which explains how I can compile it in 64 bit? I found a workaround
where I added this function to the setup.py

OrigExtension = Extension
def Extension(*args, **kwargs):
extra_args = ['-arch', 'x86_64']
kwargs['extra_compile_args'] = extra_args + kwargs.get
('extra_compile_args', [])
kwargs['extra_link_args'] = extra_args + kwargs.get('extra_link_args',
[])
return OrigExtension(*args, **kwargs)

without success. Can anyone help me? Thanks...


Cheers, Googler


From dtgeadamo at yahoo.com  Tue Jul 21 03:27:45 2009
From: dtgeadamo at yahoo.com (sightseer)
Date: Tue, 21 Jul 2009 00:27:45 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
Message-ID: <2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>

On Jul 20, 5:25?pm, "David Adamo Jr." <dtgead... at yahoo.com> wrote:
> On Jul 20, 5:14?pm, Tim Golden <m... at timgolden.me.uk> wrote:
>
>
>
> > mistersexy wrote:
> > > On Jul 20, 3:03 pm, Tim Golden <m... at timgolden.me.uk> wrote:
> > >> mistersexy wrote:
> > >>> I am trying to create a Windows service in Python using pywin32. I do
> > >>> not want this service to run under a user account. I want this service
> > >>> to be able to run as a LocalService, NetworkService and the like. How
> > >>> do I specify this using the win32 library? Thanks, everyone.
> > >> When you "install" the service, using the HandleCommandLine
> > >> option, specify --username= and --password options.
>
> > >> TJG
>
> > > That's exactly my point. I do not want to have to specify username and
> > > password options. For instance, when creating a Windows Service
> > > in .NET, it is possible to specify that the service should run using
> > > the LocalService or NetworkService account. Doing this, you would not
> > > need to specify username and password options. Is there a way to
> > > achieve this in Python?
>
> > Sorry, I misread: I mentally removed the "not" in your 'I do not want
> > this service to run under a user account' and reinserted it
> > further on!
>
> > By default, the service will run as LocalSystem: you
> > only specify a username to override that default. The value
> > in Username is passed straight through to the CreateService
> > Win32 API, and the docs for that:
>
> > ?http://msdn.microsoft.com/en-us/library/ms682450%28VS.85%29.aspx
>
> > say:
>
> > """
> > lpServiceStartName [in, optional]
>
> > ? ? The name of the account under which the service should run. If the service type is SERVICE_WIN32_OWN_PROCESS, use an account name in the form DomainName\UserName. The service process will be logged on as this user. If the account belongs to the built-in domain, you can specify .\UserName.
>
> > ? ? If this parameter is NULL, CreateService uses the LocalSystem account. If the service type specifies SERVICE_INTERACTIVE_PROCESS, the service must run in the LocalSystem account.
>
> > ? ? If this parameter is NT AUTHORITY\LocalService, CreateService uses the LocalService account. If the parameter is NT AUTHORITY\NetworkService, CreateService uses the NetworkService account.
>
> > ? ? A shared process can run as any user.
>
> > ? ? If the service type is SERVICE_KERNEL_DRIVER or SERVICE_FILE_SYSTEM_DRIVER, the name is the driver object name that the system uses to load the device driver. Specify NULL if the driver is to use a default object name created by the I/O system.
>
> > ? ? A service can be configured to use a managed account or a virtual account. If the service is configured to use a managed service account, the name is the managed service account name. If the service is configured to use a virtual account, specify the name as NT SERVICE\ServiceName. For more information about managed service accounts and virtual accounts, see the Service Accounts Step-by-Step Guide.
>
> > ? ? ? ? Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP/2000: ?Managed service accounts and virtual accounts are not supported until Windows 7 and Windows Server 2008 R2.
> > """
>
> > So, although I haven't tried it, it looks as though you can pass
> > "LocalService" or "NetworkService" and so on if you want to
> > override the default LocalSystem but don't want to specify a
> > username/password.
>
> > TJG
>
> I'll try this stuff. Thanks a million...I'll let everyone know how it
> goes.

I'm finding it hard to install my Python service. When I try to
install the service, this is what I get:

Error Installing Service: Access is Denied. (5)

Event with a correct username and password (I think).
Also, inheriting from the win32serviceutil.Framework class, I do not
see a way to explicitly specify the serviceType. I know some of the
parameters such as the startupType can be specified when installing
the service in the command line, but how are these things specified in
the service code when inheriting from win32serviceutil.Framework
(especially the serviceType).

Does this mean I would have to code my service from scratch without
using win32serviceutil.Framework? Basically, I still can't install my
service using a NetworkService or LocalSystem Account because it still
requires me to specify a username and password. Following Tim Golden's
advice, I'm trying to specify the service type in order to determine
what account to run the service under. Please help!


From hendrik at microcorp.co.za  Tue Jul 21 04:03:46 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Tue, 21 Jul 2009 10:03:46 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <200907211003.46253.hendrik@microcorp.co.za>

On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> > The main reason why you need both lists and tuples is that because a
> > tuple of immutable objects is itself immutable you can use it as a
> > dictionary key.
>
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.

simplest is something like a point in the cartesian plane with
an associated attribute like colour.

- Hendrik




From wilk at flibuste.net  Tue Jul 21 04:19:29 2009
From: wilk at flibuste.net (William Dode)
Date: 21 Jul 2009 08:19:29 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
Message-ID: <4a657a11$0$417$426a74cc@news.free.fr>

On 20-07-2009, srepmub wrote:
>
>> Nice timings, can you please show me the Python, Java and C code
>> versions? I may do more tests.

Of course, the codes are here :

http://hg.flibuste.net/libre/games/cheval

Like you'll see, i tried to use exactly the same code for each langage.

>
> also, which shedskin options did you use? did you use -bw, to disable
> bounds and wrap-around checking? this can make quite a difference for
> code that does a lot of indexing. if the code uses random numbers,
> then -r can also make a big difference, to use C rand(), instead of
> Python compatible random numbers.
>
> and which C++ compiler flags did you use? the default -O2, or
> something like -O3 -fomit-frame-pointer -msse2..?

I used the default, shedksin cheval.py; make
shedskin 0.2

With -bw and -O3 -fomit-frame-pointer -msse2 i have 5.5s (instead of 8)

Let me know if you find better.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From wilk at flibuste.net  Tue Jul 21 04:20:29 2009
From: wilk at flibuste.net (William Dode)
Date: 21 Jul 2009 08:20:29 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<mailman.3437.1248114427.8015.python-list@python.org>
	<04f03d96-46b7-4761-8498-9149f19ecba6@k6g2000yqn.googlegroups.com>
Message-ID: <4a657a4d$0$417$426a74cc@news.free.fr>

On 20-07-2009, Bearophile wrote:
> Skip Montanaro:
>> I read just enough French to know that "avec" means "with", but I don't
>> understand the difference between "avec malloc *int" and "avec []". ?Can you
>> explain please?
>
> Maybe it's the time difference between using a Python list from Cython
> and using a C "array" allocated with a malloc from Cython.

yes, it's this

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From ben+python at benfinney.id.au  Tue Jul 21 04:36:14 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 21 Jul 2009 18:36:14 +1000
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<47ab4ab6-d8c8-4997-8963-ac41b00dd10f@y10g2000prg.googlegroups.com>
Message-ID: <87ws628mbl.fsf@benfinney.id.au>

John Machin <sjmachin at lexicon.net> writes:

> OK, I'll bite: where does the Python 3.x bytearray type

I wasn't previously aware of it, thanks for bringing it to my attention
<URL:http://docs.python.org/3.1/library/stdtypes.html#bytes-methods>.

> fit into your taxonomy? At first glance it appears to be mutable and
> have a fair swag of functionality.

Yes. I'd classify it as a mutable array of bytes :-) but, as such, not
to be used as a text string.

-- 
 \                ?Science doesn't work by vote and it doesn't work by |
  `\        authority.? ?Richard Dawkins, _Big Mistake_ (The Guardian, |
_o__)                                                      2006-12-27) |
Ben Finney


From ben+python at benfinney.id.au  Tue Jul 21 04:38:31 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 21 Jul 2009 18:38:31 +1000
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <87skgq8m7s.fsf@benfinney.id.au>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:

> On Mon, 20 Jul 2009 21:08:22 +1000, Ben Finney wrote:
> > A mutable string would not (AFAICT) be usefully implementable as a
> > subclass of the built-in string types. So even if such a type
> > existed, it would not be useable with all the functionality that
> > works with strings.
> 
> If applications ignore duck-typing and do isinstance(value, str), it's
> arguably the application and not the value that is broken.

Agreed, I wouldn't advise that. My point was rather meant to imply that
subclassing the built-in (immutable) string types was the best way to
usefully get all their functionality, rather than re-implementing most
of it.

-- 
 \     ?I went to a restaurant that serves ?breakfast at any time?. So |
  `\    I ordered French Toast during the Renaissance.? ?Steven Wright |
_o__)                                                                  |
Ben Finney


From dickinsm at gmail.com  Tue Jul 21 04:51:50 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 21 Jul 2009 01:51:50 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au> 
	<4A5DE5E7.5070003@mrabarnett.plus.com> <24543805.post@talk.nabble.com> 
	<mailman.3454.1248143502.8015.python-list@python.org>
Message-ID: <8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>

On Jul 20, 11:34?pm, Ethan Furman <et... at stoneleaf.us> wrote:
> Dr. Phillip M. Feldman wrote:
> ?> Suppose that 'xor' returns the value that is true when only one value is
> ?> true, and False otherwise. ?This definition of xor doesn't have the
> standard
> ?> associative property, that is,
> ?>
> ?> (a xor b) xor c
> ?>
> ?> will not necessarily equal
> ?>
> ?> a xor (b xor c)
> ?>
> ?> To see that this is the case, let a= 1, b= 2, and c= 3.
> ?>
> ?> (a xor b) xor c
> ?>
> ?> yields 3, while
> ?>
> ?> a xor (b xor c)
> ?>
> ?> yields 1. ?So, I'd prefer an xor operator that simply returns True or
> False.
> ?>
> ?> Phillip
> ?>
>
> You are, of course, free to write your version however it makes sense to
> you and your team. ?:)
>
> Since the 'and' and 'or' already return objects (and objects evaluate to
> true or false), then 'xor' should behave likewise, IMO. ?I expect that
> would be the case if it were ever added to the language.

I'm not so sure.  Did you ever wonder why the any() and all()
functions introduced in 2.5 return a boolean rather than returning
one of their arguments?  (I did, and I'm still not sure what the
answer is.)

Mark


From juanjose.garciaripoll at googlemail.com  Tue Jul 21 05:23:59 2009
From: juanjose.garciaripoll at googlemail.com (Juanjo)
Date: Tue, 21 Jul 2009 02:23:59 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
	<61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>
Message-ID: <56721e57-e0b4-4d7d-8693-a96d1dca061b@j32g2000yqh.googlegroups.com>

On Jul 21, 6:57?am, Frank Buss <fb at frank-buss.de> wrote:
> Scott Burson wrote:
> > Have you looked atECL?
>
> >http://ecls.sourceforge.net/
>
> > I've used it only a little, so I can't vouch for its stability, but it
> > fits the threading and license requirements (well, some corporate
> > lawyers have trouble with the LGPL, but I think it's usable).
>
> I didn't tried it myself, but looks like it is not very stable:
>
> http://www.mail-archive.com/application-builder at lispniks.com/msg01069...

ECL suffers from fast development problems if this is what you mean.
People are advised to stay with certain releases and we announce when
some ports are broken due to progress along certain lines.

For instance, if I find that the generational garbage collector is
needed for Linux, FreeBSD, OpenBSD and OS X, and it works, I do not
mind dropping temporarily the mingw port until the garbage collector
library catches up. People who wanted to stay with mingw produced a
branch (see Samium's posts) with the old garbage collector.

Now this is not so dramatic. ECL now has a release cycle of ONE MONTH.
If you find that this month's release does not work on your platform
(and this is normally explicit in the announcement), then do not
upgrade and wait one or two months until the problem is solved.

OTOH, people only seem to notice problems when their petty platform is
temporarily broken, but nobody seems to notice the overall stability
and portability of the platform. See the list http://ecls.sourceforge.net/logs.html
which will soon expand including Solaris and regular builds on Windows
using the free Microsoft compiler. And once the ARM computer I have
been gifted by a happy arrives, then Debian-ARM as well.

Juanjo


From milanj at gmail.com  Tue Jul 21 05:37:27 2009
From: milanj at gmail.com (milanj)
Date: Tue, 21 Jul 2009 02:37:27 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>

On Jul 19, 8:31?pm, Frank Buss <f... at frank-buss.de> wrote:
> Python is not that bad. Unlike Lisp, there is much less undefined behavior,
> there is one free unique implementation on the 3 major platforms Linux,
> Windows and MacOS X, which is stable, support multithreading and has a
> default GUI library binding, which is difficult to find for Lisp (e.g. I
> don't know of a free modern and stable Lisp implemenation with
> mulithreading support for Windows, with a licence with which you can use it
> in closed source commercial programs, like you can do with Python). Many
> problems in the Lispbuilder mailing list are related to problems due to
> different operating systems and Lisp implementations.

> Frank Buss, f... at frank-buss.dehttp://www.frank-buss.de,http://www.it4-systems.de

Someone should mention Clozure CL - http://trac.clozure.com/openmcl
As you can see there is os x, freebsd, linux, solaris and windows port
and all of them use native threads (python still use green threads ?)
and development is pretty alive, they did planty of developing last
year[s], ccl licence permits you to deliver closed source programs ...
CCL is promising bright feature to CL since looks like the insist of
building stable implementation across most arch in use today




From martin.hellwig at dcuktec.org  Tue Jul 21 05:40:54 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 21 Jul 2009 10:40:54 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>
Message-ID: <fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>

sightseer wrote:
<knip>
> 
> Error Installing Service: Access is Denied. (5)
> 
<knip>
Are you trying to do this on windows vista?

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 05:56:33 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 06:56:33 -0300
Subject: ignore special characters in python regex
References: <4A654C01.2000508@al.com.au>
Message-ID: <op.uxewkjaxx6zn5v@gabriel.cpe.telecentro.net.ar>

En Tue, 21 Jul 2009 02:02:57 -0300, Astan Chee <astan.chee at al.com.au>  
escribi?:

> I'm reading text from a file (per line) and I want to do a regex using  
> these lines but I want the regex to ignore any special characters and  
> treat them like normal strings.
> Is there a regex function that can do this?
> Here is what I have so far:
> fp = open('file.txt','r')
> notes = fp.readlines()
> fp.close()
> strin = "this is what I want"
> for note in notes:
>      if re.search(r""+ str(note) + "",strin):
>            print "Found " + str(note) + " in " + strin

You don't even need a regex for that.

py> "fragil" in "supercalifragilisticexpialidocious"
True

Note that: r""+ str(note) + ""
is the same as: str(note)
which in turn is the same as: note

Remember that each line keeps its '\n' final!

for note in notes:
   if note.rstrip('\n') in strin:
     print "Found %s in %s" % (note, strin)

-- 
Gabriel Genellina



From duncan.booth at invalid.invalid  Tue Jul 21 06:28:16 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 21 Jul 2009 10:28:16 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<mailman.3441.1248125420.8015.python-list@python.org>
	<87hbx7yp16.fsf@busola.homelinux.net>
Message-ID: <Xns9C4F73A584B79duncanbooth@127.0.0.1>

Hrvoje Niksic <hniksic at xemacs.org> wrote:

> Chris Rebert <clp2 at rebertia.com> writes:
> 
>>>>>>>> x = [2,1,3]
>>>>>>>> print sorted(x)[0]
>>>>DB> 3
>>>
>>> What kind of Python produces that?
>>
>> Assuming you're referring to the latter example, it was added in
>> version 2.4 If you meant the former example, I think that's purely
>> pseudo-Python. 
> 
> sorted([2, 1, 3])[0] evaluates to 1, not 3.
> 

I guess you can tell I broke my unbreakable rule to never post untested 
code without labelling it as such. :-)

-- 
Duncan Booth http://kupuguy.blogspot.com


From jeanmichel at sequans.com  Tue Jul 21 06:36:14 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 21 Jul 2009 12:36:14 +0200
Subject: How to import pydoc and then use it?
In-Reply-To: <1248126024.9281.3.camel@centar>
References: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>
	<1248126024.9281.3.camel@centar>
Message-ID: <4A659A1E.9090509@sequans.com>

Albert Hopkins wrote:
> On Mon, 2009-07-20 at 13:38 -0700, mrstevegross wrote:
>   
>> I know how to use pydoc from the command line. However, because of
>> complicated environmental setup, it would be preferable to run it
>> within a python script as a native API call. That is, my python runner
>> looks a bit like this:
>>
>>   import pydoc
>>   pydoc.generate_html_docs_for(someFile)
>>
>> However, it's not clear to me from the pydoc documentation which
>> function calls I need to use to make this behavior work. Any ideas?
>>     
>
> Did you try 'pydoc pydoc'? ;)
>
>   
>>>> import pydoc
>>>> htmldoc = pydoc.HTMLDoc()
>>>> htmldoc_for_pydoc = htmldoc(pydoc)
>>>> print htmldoc_for_pydoc
>>>>         
>
>   
By the way, just in case the OP didn't know, there is the epydoc module 
(google it) which is doing basically the same things than pydoc, but 
with a much better look and feel to my opinion.

JM


From mark.dufour at gmail.com  Tue Jul 21 08:25:01 2009
From: mark.dufour at gmail.com (srepmub)
Date: Tue, 21 Jul 2009 05:25:01 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
Message-ID: <60222088-2059-49b1-a442-a56fc85d6838@g31g2000yqc.googlegroups.com>


> With -bw and -O3 -fomit-frame-pointer -msse2 i have 5.5s (instead of 8)
>
> Let me know if you find better.

thanks. now I'm wondering how fast does the C version become with
these flags..? :-)


mark.


From nick at craig-wood.com  Tue Jul 21 08:29:58 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Tue, 21 Jul 2009 07:29:58 -0500
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
Message-ID: <slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>

Mark Dufour <mark.dufour at gmail.com> wrote:
>  I have just released version 0.2 of Shed Skin, an experimental
>  (restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).
>  It comes with 7 new example programs (for a total of 40 example
>  programs, at over 12,000 lines) and several important improvements/bug
>  fixes. See http://code.google.com/p/shedskin/wiki/ReleaseNotes for the
>  full changelog.

Cool!

I tried it on a program I wrote to solve a puzzle (Rush Hour).
(Actually it solves the meta-puzzle - trying to make the hardest
possible Rush Hour puzzle.)

After a bit of twiddling (remove psyco and profiling) I got it to
start compiling, but unfortunately it compiled for about an hour (in
iterative type analysis..) used up 600 MB of RAM printing an '*' every
10 minutes or so then gave an error message and gave up.

Unfortunately I shut the window by accident, but the error message was
something about not being able to resolve types I think with a list of
20 or so unresolved types.

Can you give a hint as to how I debug this?  I presume my program has
some instances of non static types which is causing the problem, but
it is going to be a very long debugging session if it takes me an hour
each cycle ;-)

The program is about 700 lines of python (excluding comments).

Thanks

Nick
-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From wilk at flibuste.net  Tue Jul 21 08:44:30 2009
From: wilk at flibuste.net (William Dode)
Date: 21 Jul 2009 12:44:30 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<60222088-2059-49b1-a442-a56fc85d6838@g31g2000yqc.googlegroups.com>
Message-ID: <4a65b82e$0$11946$426a74cc@news.free.fr>

On 21-07-2009, srepmub wrote:
>
>> With -bw and -O3 -fomit-frame-pointer -msse2 i have 5.5s (instead of 8)
>>
>> Let me know if you find better.
>
> thanks. now I'm wondering how fast does the C version become with
> these flags..? :-)

I don't see any difference...

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From dtgeadamo at yahoo.com  Tue Jul 21 08:49:45 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Tue, 21 Jul 2009 05:49:45 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com> 
	<fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>
Message-ID: <3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>

On Jul 21, 10:40?am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
wrote:
> sightseer wrote:
>
> <knip>
>
> > Error Installing Service: Access is Denied. (5)
>
> <knip>
> Are you trying to do this on windows vista?
>
> --
> MPHhttp://blog.dcuktec.com
> 'If consumed, best digested with added seasoning to own preference.'

Yeah, I was trying to do it on Vista. Someone has just helped me out.
I had to deactivate User Account Control on Windows Vista...and now
everything is rosy. Thanks guys.


From craig1.boyd at citi.com  Tue Jul 21 08:52:19 2009
From: craig1.boyd at citi.com (Boyd, Craig1 )
Date: Tue, 21 Jul 2009 07:52:19 -0500
Subject: Auto-generate GUI from a database table structure
In-Reply-To: <op.uxdyhcvlx6zn5v@lepton.softlabbsas.com.ar>
References: <55660F9659966544BBA3AE14CE5D278D01243B8E04@exgtmb08.nam.nsroot.net>
	<op.uxdyhcvlx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <55660F9659966544BBA3AE14CE5D278D01243B8E11@exgtmb08.nam.nsroot.net>

Gabriel,

Thanks for pointing this out.  It does not look like it supports Oracle at this time, which is one of my requirements, but that is based on doing a quick read of the wiki.  I will dig in further and see.  Perhaps it supports ODBC which would be an acceptable work-around. 

Thanks again,
 
Craig

-----Original Message-----
From: python-list-bounces+craig1.boyd=citi.com at python.org [mailto:python-list-bounces+craig1.boyd=citi.com at python.org] On Behalf Of Gabriel Genellina
Sent: Monday, July 20, 2009 4:40 PM
To: python-list at python.org
Subject: Re: Auto-generate GUI from a database table structure

En Mon, 20 Jul 2009 12:09:47 -0300, Boyd, Craig1  <craig1.boyd at citi.com>
escribi?:

> I am trying to write a couple screens to update three or four database 
> tables on Oracle 10g and I was wondering if there was a way to 
> automatically generate some kind of GUI shell based on the tables that 
> I could then fill in with the logic / functionality I need.

I've never actually used it, but the DABO project seems to provide what you want: http://dabodev.com/

--
Gabriel Genellina

--
http://mail.python.org/mailman/listinfo/python-list


From paul at boddie.org.uk  Tue Jul 21 08:55:12 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Tue, 21 Jul 2009 05:55:12 -0700 (PDT)
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application 
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org> 
	<h424b1$gj1$1@panix3.panix.com>
Message-ID: <1c994086-8c58-488f-b3b3-6161c4b2ba05@k30g2000yqf.googlegroups.com>

On 20 Jul, 18:00, a... at pythoncraft.com (Aahz) wrote:
>
> Out of curiosity, are there any JavaScript toolkits that generate code
> that degrades gracefully when JavaScript is disabled?

You mean "Web toolkits which use JavaScript", I presume. I have
written (and use myself) a toolkit/framework called XSLForms (part of
the XSLTools distribution) which supports in-page updates (AJAX,
effectively) that degrade to vanilla whole-page requests if JavaScript
is switched off:

http://www.boddie.org.uk/python/XSLTools.html

I've been meaning to have a few example applications running on that
site to illustrate the point. Some people complain that by
constraining the JavaScript functionality to merely enhance vanilla
HTML/HTTP functionality, one is not using the full potential of the
medium, but having used sites whose JavaScript has failed, thus
preventing the use of those sites almost completely, I think that
stacking AJAX-like stuff on top of normal stuff helps the majority of
developers offer an accessible solution.

Paul


From rashidsdpk at gmail.com  Tue Jul 21 08:56:21 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Tue, 21 Jul 2009 05:56:21 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <2ea811b0-8135-4df2-b3c1-964414291341@g31g2000yqc.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.more link http://0nanotechnology0.blogspot.com/


From c.c.wood at gmail.com  Tue Jul 21 09:22:30 2009
From: c.c.wood at gmail.com (ChrisW)
Date: Tue, 21 Jul 2009 06:22:30 -0700 (PDT)
Subject: Multiple versions of python
Message-ID: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>

Hi,

I have installed 2 versions of python on my Windows XP computer - I
originally had 3.0.1, but then found that the MySQL module only
supported 2.*, so I've now installed that.  I have found that if I
change the Windows Environment Variable path, then I can change the
version of python called when I type 'python' into a command line.
However, I'd like to be able to choose which version I use.  I know
that if I change C:\Python26\python.exe to
C:\Python26\python2.exe and C:\Python30\python.exe to C:
\Python26\python3.exe, then typing 'python2' or 'python3' will invoke
the correct interpreter.  However, is it safe just to rename the
executable files? Is there a more elegant way to achieve the same
task?

Thanks,
Chris


From peter.fodrek at stuba.sk  Tue Jul 21 09:30:47 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Tue, 21 Jul 2009 15:30:47 +0200
Subject: Regular expression
Message-ID: <200907211530.47704.peter.fodrek@stuba.sk>

Dear conference!

I have  third party regular expression

 self.pattern_main = re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
\#\d+\=(?:[+])?\d*(?:\.\d*)?)')

with code

 def readline(self):
        self.line = self.file_in.readline().rstrip()  
	if (len(self.line)) : return True
        else : return False

 while (self.readline()):
            words = self.pattern_main.findall(self.line)


This handles text file  like

// remark
PL_OFF
PARK
FS
MA  52.8806 ,  18.0914
SS
AD_W
PL_ON
C   52.3955 ,  -16.1511 ,  -90.0000

It handles file correctly with two exceptions

1) omits ',' in the a output
2) omits minus sign in the numbers...

Would anyone recommend me what to change regular expression to add thesee two 
think to the output,please?

Thank you for any help.

I  look forward hearing form you
Yours faithfully

Peter Fodrek
 


From Scott.Daniels at Acm.Org  Tue Jul 21 09:46:12 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 21 Jul 2009 06:46:12 -0700
Subject: Mechanize not recognized by py2exe
In-Reply-To: <mailman.3455.1248150809.8015.python-list@python.org>
References: <4A60C81F.7080707@comcast.net>	<op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>
	<mailman.3455.1248150809.8015.python-list@python.org>
Message-ID: <J56dnYTMw8lJWfjXnZ2dnUVZ_qydnZ2d@pdx.net>

OrcaSoul wrote:
> ...it's too late to name my first born after you, but
> I did have a cat named Gabriel - she was a great cat!

Remember Gabriel in English uses a hard A, as in the horn
player, not Gabrielle.  I know because when I first read
his posts I made the same trick in my head, and hence
imagined a woman.  I suspect it would come to irk one
almost enough to become a Gabe.

--Scott David Daniels
Scott.Daniels at Acm.Org


From inky788 at gmail.com  Tue Jul 21 09:49:59 2009
From: inky788 at gmail.com (Inky 788)
Date: Tue, 21 Jul 2009 06:49:59 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> [snip] We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.

My guess is that it was probably for optimization reasons long ago.
I've never heard a *good* reason why Python needs both.


From Scott.Daniels at Acm.Org  Tue Jul 21 10:03:29 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 21 Jul 2009 07:03:29 -0700
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <02746e73$0$5185$c3e8da3@news.astraweb.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <MJ6dnXF-O-R9VfjXnZ2dnUVZ_gidnZ2d@pdx.net>

Steven D'Aprano wrote:
> On Mon, 20 Jul 2009 21:08:22 +1000, Ben Finney wrote:
>> What is it you're trying to do that makes you search for a mutable
>> string type? It's likely that a better approach can be found.
> 
> When dealing with very large strings, it is wasteful to have to duplicate 
> the entire string just to mutate a single character.
> 
> However, when dealing with very large strings, it's arguably better to 
> use the rope data structure instead.

The general problem is that whether strings are mutable or not is an
early language design decision, and few languages provide both.
Mutable strings need lots of data copying to be safe passing args to
unknown functions; immutable strings need lots of copying for ncremental
changes.  The rope is a great idea for some cases.

I'd argue Python works better with immutable strings, because Python is
too slow at per-character operations to be running up and down strings
a character at a time, changing here and there.  So it becomes more
natural to deal with strings as chunks to pass around, and it is nice
not to have to copy the strings when doing that passing around.

--Scott David Daniels
Scott.Daniels at Acm.Org


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Tue Jul 21 10:13:00 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Tue, 21 Jul 2009 10:13:00 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
Message-ID: <h44ipk$e7e$1@news.eternal-september.org>

On 2009-07-21 05:37:27 -0400, milanj <milanj at gmail.com> said:

> Someone should mention Clozure CL - http://trac.clozure.com/openmcl
> As you can see there is os x, freebsd, linux, solaris and windows port
> and all of them use native threads (python still use green threads ?)
> and development is pretty alive, they did planty of developing last
> year[s], ccl licence permits you to deliver closed source programs ...
> CCL is promising bright feature to CL since looks like the insist of
> building stable implementation across most arch in use today

Hear, hear!
-- 
Raffael Cavallaro



From Scott.Daniels at Acm.Org  Tue Jul 21 10:17:13 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 21 Jul 2009 07:17:13 -0700
Subject: Multiple versions of python
In-Reply-To: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
Message-ID: <E_adnRVECZqEUfjXnZ2dnUVZ_qSdnZ2d@pdx.net>

ChrisW wrote:
> Hi,
> 
> I have installed 2 versions of python on my Windows XP computer - I
> originally had 3.0.1, but then found that the MySQL module only
> supported 2.*, so I've now installed that.  I have found that if I
> change the Windows Environment Variable path, then I can change the
> version of python called when I type 'python' into a command line.
> However, I'd like to be able to choose which version I use.  I know
> that if I change C:\Python26\python.exe to
> C:\Python26\python2.exe and C:\Python30\python.exe to C:
> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
> the correct interpreter.  However, is it safe just to rename the
> executable files? Is there a more elegant way to achieve the same
> task?
I wouldn't rename them.  You can, of course, copy them (so you have two
executables), or you can pick a somedir on your path (I made a directory
"C:\cmds" that I add to my path, but tastes vary).

C:> copy con <somedir>\py25.cmd
C:\Python25\python\python.exe %*
^Z
C:> copy con <somedir>\py31.cmd
C:\Python31\python\python.exe %*
^Z

I'd use the two-digit form, as that is where interface changes
happen; trying code with py24, py25, py26 can be convenient.
By the way, install Python 3.1 rather than 3.0; think of 3.0 as the
alpha of the 3.X branches (it will get no love at all now that 3.1
is out).

--Scott David Daniels
Scott.Daniels at Acm.Org


From davea at dejaviewphoto.com  Tue Jul 21 10:19:42 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Tue, 21 Jul 2009 10:19:42 -0400
Subject: Multiple versions of python
In-Reply-To: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
Message-ID: <4A65CE7E.6090800@dejaviewphoto.com>

ChrisW wrote:
> Hi,
>
> I have installed 2 versions of python on my Windows XP computer - I
> originally had 3.0.1, but then found that the MySQL module only
> supported 2.*, so I've now installed that.  I have found that if I
> change the Windows Environment Variable path, then I can change the
> version of python called when I type 'python' into a command line.
> However, I'd like to be able to choose which version I use.  I know
> that if I change C:\Python26\python.exe to
> C:\Python26\python2.exe and C:\Python30\python.exe to C:
> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
> the correct interpreter.  However, is it safe just to rename the
> executable files? Is there a more elegant way to achieve the same
> task?
>
> Thanks,
> Chris
>
>   
The elegant way is to have a batch directory on your PATH ( I use  
m:\t\bat )  and put your *.bat files there.   I do NOT put any python 
installations on the PATH.

For example, I have a batch file called:     m:\t\bat\python26.bat

c:\progfiles\python26\python.exe %*

The %* syntax means pass all arguments through to the program.

Once it all works, you can add an "@" in front of the c:   in order to 
suppress echoing the command.  At that point, it'll look and work the 
same way as what you did, but without modifying anything in the install 
directory.    (You may want  python26.bat, pythonw26.bat, python31.bat 
and pythonw31.bat)



The other thing you may want to do in a batch file is to change the file 
associations so that you can run the .py file directly, without typing 
"python" or "pythonw" in front of it.

The relevant Windows commands are:     assoc and ftype      And on a 
related note, you may want to edit the PATHEXT environment variable, to 
add .PY and .PYW




From hv at tbz-pariv.de  Tue Jul 21 10:27:27 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Tue, 21 Jul 2009 16:27:27 +0200
Subject: Workflow Libraries (DB vs Code)
Message-ID: <7cm1ifF28jmnhU1@mid.individual.net>

Hi,

I need to write some simple workflows with web interface.

For the web stuff I will use django, but I am not sure how
to do the workflow part.

Here are ideas:

Do it myself. I don't think it will be difficult, I did things like
this before. But they were not reusable.

Use spiff Workflow library http://code.google.com/p/spiff-workflow/

Use goflow for django (port of OpenFlow of Zope). It does not look like a active project.

Has anyone worked with spiff, goflow or other workflow software? What do you like and
dislike?

Somehow I like it the way goflow does it: The process definitions are stored
in the database. But on the other hand I prefer to have things like this in
a SVN-Repository.

Creating the workflow definitions will be done by python programmers. I don't need
a GUI to build them.

There are many languages to define processes (BPML, XPDL, BPEL or YAWL). But I prefer python.

Feedback welcome,

  Thomas

-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From sajmikins at gmail.com  Tue Jul 21 10:30:56 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 07:30:56 -0700 (PDT)
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com> 
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
Message-ID: <b648f2ba-f589-4c4a-a729-5c9c4551603c@s31g2000yqs.googlegroups.com>

On Jul 20, 3:29?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac <alan.is... at gmail.com> ?
> escribi?:
>
> >> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
> >>> def apply2(itr, methodname, *args, **kwargs):
> >>> ? ? f = operator.methodcaller(methodname, *args, **kwargs)
> >>> ? ? for item in itr:
> >>> ? ? ? ? f(item)
>
> > On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
> >> for obj in objects:
> >> ? ? getattr(obj, methodname)(*args, **kwargs)
>
> > Are there any obvious considerations in choosing
> > between those two?
>
> The operator.methodcaller version is faster in my tests for large ?
> collections, but slightly slower when you have very few elements.
>
> <code>
> import operator
> import timeit
>
> class X:
> ? ?def method(self, x, y, **kw): pass
>
> def apply1(itr, methodname, *args, **kwargs):
> ? ? ?for item in itr:
> ? ? ? ? ?getattr(item, methodname)(*args, **kwargs)
>
> def apply2(itr, methodname, *args, **kwargs):
> ? ? ?f = operator.methodcaller(methodname, *args, **kwargs)
> ? ? ?for item in itr:
> ? ? ? ? ?f(item)
>
> L=[X() for _ in range(3000)]
> apply1(L,'method', 1, 2, foo=3)
> apply2(L,'method', 1, 2, foo=3)
>
> timeit.timeit(setup="from __main__ import apply1,apply2,L", ?
> stmt="apply1(L,'method', 1, 2, foo=3)", number=1000)
> timeit.timeit(setup="from __main__ import apply1,apply2,L", ?
> stmt="apply2(L,'method', 1, 2, foo=3)", number=1000)
> </code>
>
> --
> Gabriel Genellina

If your instances are all of the same class you can pass in the method
directly like so:

def apply3(iterator, method, *args, **kwargs):
    for item in iterator:
        method(item, *args, **kwargs)

class X:
   def method(self, x, y, **kw): pass

items = [X() for _ in range(10)]

apply3(items, X.method, 1, 2, foo=3)

HTH,
~Simon


From sajmikins at gmail.com  Tue Jul 21 10:42:08 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 10:42:08 -0400
Subject: tough-to-explain Python
In-Reply-To: <7xws627qc1.fsf@ruckus.brouhaha.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7xljmk8q1m.fsf@ruckus.brouhaha.com>
	<6348dcb8-bfc1-446e-b7bf-28657e2b607e@j32g2000yqh.googlegroups.com>
	<7xws627qc1.fsf@ruckus.brouhaha.com>
Message-ID: <50f98a4c0907210742q47aa3e21s9a410e833ab78718@mail.gmail.com>

On Mon, Jul 20, 2009 at 9:54 PM, Paul Rubin<http://phr.cx at nospam.invalid> wrote:
> Simon Forman <sajmikins at gmail.com> writes:
>> But I'm glad it's there to study, these are wheels I don't have to
>> invent for myself.
>
> http://dwheeler.com/essays/high-assurance-floss.html
>
> might be an interesting place to start.

OO la la!  Thank you!


From slobodan.blazeski at gmail.com  Tue Jul 21 10:42:18 2009
From: slobodan.blazeski at gmail.com (Slobodan Blazeski)
Date: Tue, 21 Jul 2009 07:42:18 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <03fef26b-b8ed-4863-ba55-309624c97eff@o6g2000yqj.googlegroups.com>

On Jul 19, 7:33?pm, fft1976 <fft1... at gmail.com> wrote:
> On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:
>
> > E.g. the number system: In many Lisp
> > implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> > "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> > it returns "0.6666666666", which will result in lots of fun for porting
> > applications written for Python <= 2.6.
>
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

Worse is better?

Bobi
http://www.linkedin.com/in/slobodanblazeski


From bearophileHUGS at lycos.com  Tue Jul 21 10:46:26 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 21 Jul 2009 07:46:26 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
Message-ID: <ada772ff-f8b6-4442-84f8-15ef663ac200@26g2000yqk.googlegroups.com>

Nick Craig-Wood:
> Can you give a hint as to how I debug this? ?I presume my program has
> some instances of non static types which is causing the problem, but
> it is going to be a very long debugging session if it takes me an hour
> each cycle ;-)
>
> The program is about 700 lines of python (excluding comments).

You can show us the Python (SSPython) code, and we can try to find the
problem. Sometimes there's no simple ways to solve such problems.

Generally for not very large progrograms if SS doesn't compile in
about a minute or so then it's gone in infinite loop (there's a
compilation flag that avoids some infinite loops, try it).

Bye,
bearophile


From python at mrabarnett.plus.com  Tue Jul 21 10:50:15 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 21 Jul 2009 15:50:15 +0100
Subject: Regular expression
In-Reply-To: <200907211530.47704.peter.fodrek@stuba.sk>
References: <200907211530.47704.peter.fodrek@stuba.sk>
Message-ID: <4A65D5A7.9060908@mrabarnett.plus.com>

Peter Fodrek wrote:
> Dear conference!
> 
> I have  third party regular expression
> 
>  self.pattern_main = re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')
> 
[snip]
> It handles file correctly with two exceptions
> 
> 1) omits ',' in the a output
> 2) omits minus sign in the numbers...
> 
> Would anyone recommend me what to change regular expression to add thesee two 
> think to the output,please?
> 

self.pattern_main = 
re.compile(r'(\s+|,|-?\w\+?\d*(?:\.\d*)?|\w#\d+|\(.*?\)|#\d+=\+?\d*(?:\.\d*)?)')


From piet at cs.uu.nl  Tue Jul 21 11:05:36 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 17:05:36 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
	<mailman.3460.1248163342.8015.python-list@python.org>
Message-ID: <m2r5wam5z3.fsf@cs.uu.nl>

>>>>> Hendrik van Rooyen <hendrik at microcorp.co.za> (HvR) wrote:

>HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>>> > The main reason why you need both lists and tuples is that because a
>>> > tuple of immutable objects is itself immutable you can use it as a
>>> > dictionary key.
>>> 
>>> Really? That sounds interesting, although I can't think of any real-
>>> world cases where you'd use something like that.

>HvR> simplest is something like a point in the cartesian plane with
>HvR> an associated attribute like colour.

There are numerous other examples. Anytime you need a key that is not a
single object but composed of more than one:
Name + birthday
Street + number + City
Student + Course
etc.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From bearophileHUGS at lycos.com  Tue Jul 21 11:08:37 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 21 Jul 2009 08:08:37 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
Message-ID: <4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>

William Dode':
> http://hg.flibuste.net/libre/games/cheval
> Like you'll see, i tried to use exactly the same code for each langage.

It's a cute solver.

Few more versions of mine:

#1, a Psyco version of mine:
http://codepad.org/9m5rf7kX

#2, unrolled Psyco version:
http://codepad.org/gKFLu34M

#3, a quick D (D1) version:
http://codepad.org/Tk9FL7Xk

Timings (no printing), seconds, best of 3:
#1: 4.79
#2: 3.67
#3: 1.10
Your Psyco version: 13.37
Your C version, compiled with GCC 4.3.2, -s -O3 -fomit-frame-pointer:
3.79

I have timed the whole running time of the programs, with an external
timer, so my timings include the start of the PythonVM and the final
cleanup of the GC.

Please, feel free to time my code again, so we can compare with your
other timings (Java, etc) better.

I have used Psyco 1.6 final and Python 2.6.2 on a Core2 CPU at 2 GHz.

To compile the D1 code you can use the free DMD compiler for D1, I
have used version 1.042, www.digitalmars.com/d/download.html ).

In such benchmarks it's often better to start from the fastest low
level code (written in an imperative language as C/D/C++, or a version
in a functional language like Clean or OCaML) and then use it to
create higher level versions (in Python, etc). This offers you a
baseline timing, and usually the small differences of the higher level
code compared to the original C/Clean code don't invalidate the test.

I have changed only small things in the program, as you can see the
Psyco program #2 is faster than your C code :-) If you learn how to
use it well, Psyco1.6 can often lead to very good performance. But lot
of people don't know how to use Psyco well (I too am ignorant: I don't
know how to profile Python programs yet).

Bye,
bearophile


From dns4 at cornell.edu  Tue Jul 21 11:14:37 2009
From: dns4 at cornell.edu (David Smith)
Date: Tue, 21 Jul 2009 11:14:37 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <m2r5wam5z3.fsf@cs.uu.nl>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
	<mailman.3460.1248163342.8015.python-list@python.org>
	<m2r5wam5z3.fsf@cs.uu.nl>
Message-ID: <h44m12$hql$1@ruby.cit.cornell.edu>

Piet van Oostrum wrote:
>>>>>> Hendrik van Rooyen <hendrik at microcorp.co.za> (HvR) wrote:
> 
>> HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>>> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>>>>> The main reason why you need both lists and tuples is that because a
>>>>> tuple of immutable objects is itself immutable you can use it as a
>>>>> dictionary key.
>>>> Really? That sounds interesting, although I can't think of any real-
>>>> world cases where you'd use something like that.
> 
>> HvR> simplest is something like a point in the cartesian plane with
>> HvR> an associated attribute like colour.
> 
> There are numerous other examples. Anytime you need a key that is not a
> single object but composed of more than one:
> Name + birthday
> Street + number + City
> Student + Course
> etc.

Compound keys (like what's listed above) can also be used for sorting
lists of dictionaries using DSU style sorting.  Something I believe (and
 I could be wrong) won't work with mutable types like lists.

--David


From piet at cs.uu.nl  Tue Jul 21 11:32:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 17:32:26 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
	<mailman.3460.1248163342.8015.python-list@python.org>
	<m2r5wam5z3.fsf@cs.uu.nl> <h44m12$hql$1@ruby.cit.cornell.edu>
Message-ID: <m2my6ym4qd.fsf@cs.uu.nl>

>>>>> David Smith <dns4 at cornell.edu> (DS) wrote:

>DS> Piet van Oostrum wrote:
>>>>>>>> Hendrik van Rooyen <hendrik at microcorp.co.za> (HvR) wrote:
>>> 
>HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>>>>> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>>>>> The main reason why you need both lists and tuples is that because a
>>>>> tuple of immutable objects is itself immutable you can use it as a
>>>>> dictionary key.
>>>>>> Really? That sounds interesting, although I can't think of any real-
>>>>>> world cases where you'd use something like that.
>>> 
>HvR> simplest is something like a point in the cartesian plane with
>HvR> an associated attribute like colour.
>>> 
>>> There are numerous other examples. Anytime you need a key that is not a
>>> single object but composed of more than one:
>>> Name + birthday
>>> Street + number + City
>>> Student + Course
>>> etc.

>DS> Compound keys (like what's listed above) can also be used for sorting
>DS> lists of dictionaries using DSU style sorting.  Something I believe (and
>DS>  I could be wrong) won't work with mutable types like lists.

For sorting there is no problem with mutable arrays as long as you don't
mutate them during the sorting process (for example in the comparison
routine). Doing that would be extremely perverse. And there is no
enforcement of that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From ethan at stoneleaf.us  Tue Jul 21 11:34:19 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 21 Jul 2009 08:34:19 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>
References: <24485116.post@talk.nabble.com>	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<4A5DE5E7.5070003@mrabarnett.plus.com>
	<24543805.post@talk.nabble.com>
	<mailman.3454.1248143502.8015.python-list@python.org>
	<8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>
Message-ID: <4A65DFFB.3090004@stoneleaf.us>

Mark Dickinson wrote:
> On Jul 20, 11:34 pm, Ethan Furman <et... at stoneleaf.us> wrote:
> 
>>Dr. Phillip M. Feldman wrote:
>> > Suppose that 'xor' returns the value that is true when only one value is
>> > true, and False otherwise.  This definition of xor doesn't have the
>>standard
>> > associative property, that is,
>> >
>> > (a xor b) xor c
>> >
>> > will not necessarily equal
>> >
>> > a xor (b xor c)
>> >
>> > To see that this is the case, let a= 1, b= 2, and c= 3.
>> >
>> > (a xor b) xor c
>> >
>> > yields 3, while
>> >
>> > a xor (b xor c)
>> >
>> > yields 1.  So, I'd prefer an xor operator that simply returns True or
>>False.
>> >
>> > Phillip
>> >
>>
>>You are, of course, free to write your version however it makes sense to
>>you and your team.  :)
>>
>>Since the 'and' and 'or' already return objects (and objects evaluate to
>>true or false), then 'xor' should behave likewise, IMO.  I expect that
>>would be the case if it were ever added to the language.
> 
> 
> I'm not so sure.  Did you ever wonder why the any() and all()
> functions introduced in 2.5 return a boolean rather than returning
> one of their arguments?  (I did, and I'm still not sure what the
> answer is.)
> 
> Mark


Very good question -- I likewise do not know the answer.  I will only 
observe that any() and all() are functions, while 'and' and 'or' are 
not.  If one wanted the object-returning behavior one could string 
together 'or's or 'and's instead.

~Ethan~
--
Thinking out loud here -- YMMV.  :)


From rhodri at wildebst.demon.co.uk  Tue Jul 21 11:39:51 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 21 Jul 2009 16:39:51 +0100
Subject: Regular expression
In-Reply-To: <200907211530.47704.peter.fodrek@stuba.sk>
References: <200907211530.47704.peter.fodrek@stuba.sk>
Message-ID: <op.uxfcgpzua8ncjz@gnudebst>

On Tue, 21 Jul 2009 14:30:47 +0100, Peter Fodrek <peter.fodrek at stuba.sk>  
wrote:

> Dear conference!
>
> I have  third party regular expression
>
>  self.pattern_main =  
> re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')

Always use raw strings (r"...") when you're working with regular
expressions.  *Always*.  It may happen that you don't need them,
as in this case, because Python fails to throw an exception when
it meets unknown escape sequences in string literals, but when
you do need them you will spend hours before realising it.

Also, whoever wrote this regular expression should be taken
out and slapped with a wet fish, for it is abominable and
unlikely to look much like what you actually want.

> with code
>
>  def readline(self):
>         self.line = self.file_in.readline().rstrip()
> 	if (len(self.line)) : return True
>         else : return False
>
>  while (self.readline()):
>             words = self.pattern_main.findall(self.line)

Um.  Yes.  Well.

> This handles text file  like
>
> // remark
> PL_OFF
> PARK
> FS
> MA  52.8806 ,  18.0914
> SS
> AD_W
> PL_ON
> C   52.3955 ,  -16.1511 ,  -90.0000
>
> It handles file correctly with two exceptions
>
> 1) omits ',' in the a output

You don't do any output, so it's hard to correct that!

> 2) omits minus sign in the numbers...
>
> Would anyone recommend me what to change regular expression to add  
> thesee two
> think to the output,please?

It would help considerably if you explained what "it handles file
correctly" means, since the regular expresion makes little sense
with the input you give.  What are you trying to extract from the
input, and what do you think you are getting at the moment?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From c.c.wood at gmail.com  Tue Jul 21 11:51:08 2009
From: c.c.wood at gmail.com (CCW)
Date: Tue, 21 Jul 2009 08:51:08 -0700 (PDT)
Subject: Multiple versions of python
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
	<mailman.3465.1248186000.8015.python-list@python.org>
Message-ID: <98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>

On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
> ChrisW wrote:
> > Hi,
>
> > I have installed 2 versions of python on my Windows XP computer - I
> > originally had 3.0.1, but then found that the MySQL module only
> > supported 2.*, so I've now installed that. ?I have found that if I
> > change the Windows Environment Variable path, then I can change the
> > version of python called when I type 'python' into a command line.
> > However, I'd like to be able to choose which version I use. ?I know
> > that if I change C:\Python26\python.exe to
> > C:\Python26\python2.exe and C:\Python30\python.exe to C:
> > \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
> > the correct interpreter. ?However, is it safe just to rename the
> > executable files? Is there a more elegant way to achieve the same
> > task?
>
> > Thanks,
> > Chris
>
> The elegant way is to have a batch directory on your PATH ( I use ?
> m:\t\bat ) ?and put your *.bat files there. ? I do NOT put any python
> installations on the PATH.
>
> For example, I have a batch file called: ? ? m:\t\bat\python26.bat
>
> c:\progfiles\python26\python.exe %*
>
> The %* syntax means pass all arguments through to the program.
>
> Once it all works, you can add an "@" in front of the c: ? in order to
> suppress echoing the command. ?At that point, it'll look and work the
> same way as what you did, but without modifying anything in the install
> directory. ? ?(You may want ?python26.bat, pythonw26.bat, python31.bat
> and pythonw31.bat)
>
> The other thing you may want to do in a batch file is to change the file
> associations so that you can run the .py file directly, without typing
> "python" or "pythonw" in front of it.
>
> The relevant Windows commands are: ? ? assoc and ftype ? ? ?And on a
> related note, you may want to edit the PATHEXT environment variable, to
> add .PY and .PYW

Thanks for this - this way made a bit more sense to me.  I've now got
C:\commands with the 4 .bat files in, and C:\commands in my path.  It
all seems to work :) I think I've missed the point of the @ though -
it doesn't seem to make any difference..

I'm also a bit confused with the associations - since I've got python
2.6 and 3.1, surely the command I type (python26 or python31) is the
only way to force a script to be run using a specific interpreter at
runtime without having to change the .bat file every time I want to
run a script using 3.1 instead of 2.6?


From peter.fodrek at stuba.sk  Tue Jul 21 11:51:32 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Tue, 21 Jul 2009 17:51:32 +0200
Subject: Regular expression
In-Reply-To: <4A65D5A7.9060908@mrabarnett.plus.com>
References: <200907211530.47704.peter.fodrek@stuba.sk>
	<4A65D5A7.9060908@mrabarnett.plus.com>
Message-ID: <86771222-4E27-4E0C-BC56-948169A277BF@stuba.sk>


21.7.2009 v 16:50, MRAB:

> Peter Fodrek wrote:
>> Dear conference!
>> I have  third party regular expression
>> self.pattern_main = re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d 
>> +|\(.*?\)|
>> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')
> [snip]
>> It handles file correctly with two exceptions
>> 1) omits ',' in the a output
>> 2) omits minus sign in the numbers...
>> Would anyone recommend me what to change regular expression to add  
>> thesee two think to the output,please?
>
> self.pattern_main = re.compile(r'(\s+|,|-?\w\+?\d*(?:\.\d*)?|\w#\d+|\ 
> (.*?\)|#\d+=\+?\d*(?:\.\d*)?)')

Thank you I will try yesterday...

Peter 


From deets at nospam.web.de  Tue Jul 21 11:58:47 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 21 Jul 2009 17:58:47 +0200
Subject: Workflow Libraries (DB vs Code)
References: <7cm1ifF28jmnhU1@mid.individual.net>
Message-ID: <7cm6kmF26g9srU1@mid.uni-berlin.de>

Thomas Guettler wrote:

> Hi,
> 
> I need to write some simple workflows with web interface.
> 
> For the web stuff I will use django, but I am not sure how
> to do the workflow part.

Did you consider using OpenERP? It comes with a web-frontend
(TG1.0.8-based), but also offers a XMLRPC-server to connect to, so using it
from within django shouldn't be any difficult.

Workflow-definitions are stored in the DB, and can be generated visually,
not sure if they have to though.

I'm not very familiar with the system myself, but the EuroPython
presentation was truly impressive.

Diez


From piet at cs.uu.nl  Tue Jul 21 11:59:47 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 17:59:47 +0200
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
Message-ID: <m2iqhmm3gs.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> M2Crypto package not showing the 'recipient_public_key.pem' file at
>j> linux terminal .how do i get/connect with recipient public key.

>j> exactly i need to check how can i open this file through linux
>j> commands.

>j> import M2Crypto def encrypt(): recip = M2Crypto.RSA.load_pub_key(open
>j> ('recipient_public_key.pem','rb').read()) print recip; plaintext =
>j> whatever i need to encrypt msg = recip.public_encrypt
>j> (plaintext,RSA.pkcs1_padding) print msg;

>j> after calling the function its not giving any output and even any
>j> error

>j> i also tried as 'Will' said

>j> pk = open('public_key.pem','rb').read() print pk; rsa =
>j> M2Crypto.RSA.load_pub_key(pk)

>j> whats the mistake i am not getting .will somebody help me out.
>j> is something wrong in opening 'recipient_public_key.pem'. is M2Crypto
>j> contain this file inbuilt .from where this file taking public key of
>j> the recipient i'. what this file contain and how it will work .should
>j> i need to create such a file for my purpose.if it is then how can i
>j> create this  and how it will retrieve the key,where i recognize my
>j> recipient to get his public key .is something like database at server.

>j> please give me a quick response......
>j> looking for your answer.

Please:
1. Type your python code with newlines and proper indentation.
2. Show the error messages that your code gives when you run it.
3. Use proper capital letters at the beginning of your sentences.
4. Don't fire so many questions in rapid succession.

The recipient_public_key.pem file is the public key of the recipient
which means the person that is going to receive the encrypted message.
You should get it from the recipient him/herself or from some key store
where s/he has deposited it.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From iwan at reahl.org  Tue Jul 21 12:05:31 2009
From: iwan at reahl.org (Iwan Vosloo)
Date: Tue, 21 Jul 2009 18:05:31 +0200
Subject: Issue combining gzip and subprocess
Message-ID: <1248192331.30167.38.camel@easymoney>

Hi there,

We tried to gzip the output of a shell command, but this results in a
strange error: the resulting file seems to be the concatenation of the
plaintext file with the zipped content.

For example:

f = gzip.open(filename, 'w')
subprocess.check_call(['ls','-la'], stdout=f)
f.close()

Using a normal file works as expected, but a GzipFile results in a file
containing what looks like the unzipped data, followed by the zipped
data.

I suspect this may have something to do with limitations of GzipFile
such as it not implementing truncate().

Does anyone have an explanation / can you suggest a nice solution for
doing what we are trying to do?

Regards
- Iwan



From nad at acm.org  Tue Jul 21 12:08:48 2009
From: nad at acm.org (Ned Deily)
Date: Tue, 21 Jul 2009 09:08:48 -0700
Subject: PIL for OSX 64bit
References: <e0564f03-f736-4d0f-8c50-e1bce0eb55f8@r2g2000yqm.googlegroups.com>
Message-ID: <nad-29B43F.09084821072009@ger.gmane.org>

In article 
<e0564f03-f736-4d0f-8c50-e1bce0eb55f8 at r2g2000yqm.googlegroups.com>,
 moerchendiser2k3 <googler.1.webmaster at spamgourmet.com> wrote:
> I have a problem with Python and the Python Image Library to get it
> work on OSX 64 bit. Maybe anyone can help me? I started Python in 64
> bit mode and called Image.open(...).load() and got:
> 
> ImportError: The _imaging C module is not installed
[...]

It's hard to know what your problem is without more information.  One 
potential stumbling block: PIL has dependencies on other open-source 
libraries, such as libjpeg and freetype.  You'll need to have 64-bit 
versions of them available when building and when running, as well.  
There are a number of ways to do that.  The simplest might be to 
download pre-built frameworks containing those libraries from here:

http://www.kyngchaos.com/software:frameworks

There are also build scripts there for building your own versions from 
scratch.

-- 
 Ned Deily,
 nad at acm.org



From sajmikins at gmail.com  Tue Jul 21 12:10:57 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 09:10:57 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <c46904d7-d8c5-4d64-8d34-11b0aec1969b@s31g2000yqs.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> My colleagues and I have been working with python for around 6 months
> now, and while we love a lot of what python has done for us and what
> it enables us to do some of the decisions behind such certain
> data-types and their related methods baffle us slightly (when compared
> to the decisions made in other, similarly powerful languages).
>
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
>
> Consider the following:
>
> >>> x = [2,1,3]
> >>> x.sort()
> >>> print x
>
> [1, 2, 3]
>
> Now, if the sort operations were unable to affect the original
> structure of the list (as in JavaScript) you'd effectively have a
> tuple which you could add/remove from, and the example above would
> look more like:
>
> >>> x = [2,1,3]
> >>> print x.sort()
> [1, 2, 3]
> >>> print x
>
> [2,1,3]
>
> This make a lot more sense to us, and follows the convention from
> other languages. It would also mean chaining methods to manipulate
> lists would be easier:
>
> >>> x = [2,1,3]
> >>> print x.sort()[0]
> 3

(As others have already pointed out this would print 1, not 3.)

> >>> print x
>
> [2,1,3]
>
> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.

In this case you can use:

>>> x = [2,1,3]
>>> print min(x)
1

(There's also a max() function.)

> We're not looking to start any arguments or religious wars and we're
> not asking that python be changed into something its not. We'd simply
> like to understand the decision behind the lists and tuple structures.
> We feel that in not "getting" the difference between the two types we
> may be missing out on using these data structures to their full
> potential.


One way to think about tuples (as distinct from lists) is as a short-
hand version of Pascal's 'record' type, or C's 'struct' (with the
caveats that the fields are not named, only indexed, and the types of
the fields are implied by use, not explicitly declared.)

(FWIW: http://en.wikipedia.org/wiki/Record_(computer_science) )

Broadly speaking, lists are useful for things like stacks and queues,
and sorting, while tuples are useful for aggregating heterogeneous
data into coherent units, and you can hash them (provided their
contents are also hashable.)

HTH,
~Simon


From stef.mientki at gmail.com  Tue Jul 21 12:13:30 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Tue, 21 Jul 2009 18:13:30 +0200
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <h428fp$8ja$2@adenine.netfront.net>
References: <mailman.3406.1248034495.8015.python-list@python.org>	<h40adj$bv6$1@adenine.netfront.net>	<mailman.3419.1248082444.8015.python-list@python.org>
	<h428fp$8ja$2@adenine.netfront.net>
Message-ID: <4A65E92A.3050608@gmail.com>

hi Marcus,
>>> That sounds like a very specialized type of thing, 
>> Well from an application point of view,
>> with the current netbooks,
>> this looks like a perfect tool for any conversation or meeting.
>>> which only the few people with experience with wxPython, PyAudio, 
>>> and Scintilla could help you with...
>>>
>> I was afraid of that too, so I dropped the question in several places,
>> and the writer of Scintilla himself came with the perfect answer.
>>
>> cheers,Stef
>>> But you might try having a dictionary with notes and associated 
>>> times, or just give each note a four-digit ID number at the 
>>> beginning of it when it's entered and use that in the dictionary (to 
>>> keep keys shorter). Or you could just do a little hack and increase 
>>> the number of bookmarks allowed (seeing as source is available) :p
>>>
>>> Marcus
>>
> Glad you got a good answer from somebody. Sounds like an interesting 
> project. About when would this be headed for a release? Could you post 
> a link to a googlecode or sourceforge project or something so I can 
> follow and/or help with development?
>
For the moment it's just an idea, so no line of code yet.
I first like to tackle all the problems,
at least to the level I think I can handle them.
So first solve the next problem,
before I start coding:
automatic synchronization (file uploading and deleting) between EEE-pc 
and desktop PC over bluetooth.
And another problem, as my customers are physicians,
both the text and audio need to be stored encrypted.

cheers,
Stef
> Marcus



From fb at frank-buss.de  Tue Jul 21 12:44:23 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 18:44:23 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
	<61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>
	<f2361d71-dd8b-45cc-89fc-edf39e57197a@24g2000yqm.googlegroups.com>
Message-ID: <1t9jyo7lzm3ke.hh1blip7i2yp.dlg@40tude.net>

Rainer Joswig wrote:

> I'm not sure if it is fair to post a reference to a single
> post by someone without context and without having used ECL.
> If there are stability problems, people can report to the
> ECL mailing list. The maintainers are very active.

This was just one example. Another one:

http://www.mail-archive.com/application-builder at lispniks.com/msg01024.html

Luke and Elliott are no beginners, so it is at least difficult to use ECL:
On Windows it doesn't work with MinGW and on MacOS X there was at least one
case were it freezed. But as I have written, I didn't tried it myself, so
this is only some second hand experience. Maybe it is all wrong setups in
combination with Lispbuilder and ECL itself is stable, I don't know.

But I know that it is much easier to get a full featured running Python
system on Windows, MacOS X and Linux, so this is something where Lisp
distributions could be improved.

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From nagle at animats.com  Tue Jul 21 12:48:38 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 21 Jul 2009 09:48:38 -0700
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system()
	that  doesn't block gui event loops
In-Reply-To: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <4a65f0d8$0$1599$742ec2ed@news.sonic.net>

Ville Vainio wrote:
> Has anyone implementing something like what the subject line
> indicates?
> 
> The idea:
> 
> To run functions that execute a series of system commands without
> blocking the ui, *and* without adding state machine logic.

    At some level, there's going to be state machine logic.
You need interlocking so that the user can't initiate
simultaneous conflicting background operations from the GUI.

    The usual solution is to run the background operations
in another thread, and have them put events on a queue
read by the GUI task.

    You also have to work out how to cancel background operations,
if they're going to be as big as a "make".

    Here's the very first application which did this sort of thing,
running commands in multiple threads without blocking the user
interface thread.  This is from 1972.

    http://www.fourmilab.ch/documents/univac/fang/

    And yes, it did properly interlock everything it was
doing in the background.

				John Nagle


From piet at cs.uu.nl  Tue Jul 21 12:50:00 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 18:50:00 +0200
Subject: Issue combining gzip and subprocess
References: <mailman.3472.1248192725.8015.python-list@python.org>
Message-ID: <m2eisam153.fsf@cs.uu.nl>

>>>>> Iwan Vosloo <iwan at reahl.org> (IV) wrote:

>IV> Hi there,
>IV> We tried to gzip the output of a shell command, but this results in a
>IV> strange error: the resulting file seems to be the concatenation of the
>IV> plaintext file with the zipped content.

>IV> For example:

>IV> f = gzip.open(filename, 'w')
>IV> subprocess.check_call(['ls','-la'], stdout=f)
>IV> f.close()

>IV> Using a normal file works as expected, but a GzipFile results in a file
>IV> containing what looks like the unzipped data, followed by the zipped
>IV> data.

>IV> I suspect this may have something to do with limitations of GzipFile
>IV> such as it not implementing truncate().

>IV> Does anyone have an explanation / can you suggest a nice solution for
>IV> doing what we are trying to do?

stdout (and the others) must be None, PIPE or a real file object or file
descriptor, not a file like object. In your case the solution would be
to use PIPE, and then read the output and write in to the GzipFile
yourself. 

f = gzip.open(filename, 'w')
proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
while True:
    line = proc.stdout.readline()
    if not line: break
    f.write(line)
f.close()

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mail at timgolden.me.uk  Tue Jul 21 13:07:49 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Tue, 21 Jul 2009 18:07:49 +0100
Subject: win32api install problem
In-Reply-To: <b1b9ef55-c740-4a9e-ba33-4aa1e88dc5f5@f33g2000vbm.googlegroups.com>
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>	<mailman.3424.1248098235.8015.python-list@python.org>
	<b1b9ef55-c740-4a9e-ba33-4aa1e88dc5f5@f33g2000vbm.googlegroups.com>
Message-ID: <4A65F5E5.3060903@timgolden.me.uk>

MCIPERF wrote:
> On Jul 20, 9:57 am, Tim Golden <m... at timgolden.me.uk> wrote:
>> Gerry wrote:
>>> I'm running Python 2.6 under XP.
>>> I've installed Windows 32 extensions for Python 2.6 version 1.4
>>> (pywin32-214.win32-py2.6.exe).
>>> But If I try to import win32api, I get:
>>>   File "C:\python_projects\euler\driveletters.py", line 1, in <module>
>>>     import win32api
>>> ImportError: DLL load failed: The specified module could not be found.
>> Used to be you'd get this error if you installed as a
>> non-admin user. Don't know if that's still an issue.
>> Possibility?
>>
>> TJG
> 
> Not a possibility (afaict) -- I am an administrator, according to the
> control panel.

Not too many ideas, then, I'm afraid. Apart from the obvious --
uninstall and try again -- how about running Python with the
-vv option:

python -vv

to get more information about what it's trying to get, 
and/or running sysinternal's Process Explorer at the
same time to spot the DLL Dependencies.

I have seen a (not too similar) problem when running TortoiseHg
and the pywin32 extensions, since the shell import's TortoiseHg's
version of various pywin32 DLLs before I try to import them
myself for some other purpose, and the two versions clashed
dramatically (crashed Explorer hard, I seem to remember).

Just in case that rings any bells..

TJG


From jeanmichel at sequans.com  Tue Jul 21 13:22:05 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 21 Jul 2009 19:22:05 +0200
Subject: Regular expression
In-Reply-To: <op.uxfcgpzua8ncjz@gnudebst>
References: <200907211530.47704.peter.fodrek@stuba.sk>
	<op.uxfcgpzua8ncjz@gnudebst>
Message-ID: <4A65F93D.8000908@sequans.com>

Rhodri James wrote:
> On Tue, 21 Jul 2009 14:30:47 +0100, Peter Fodrek 
> <peter.fodrek at stuba.sk> wrote:
>
>> Dear conference!
>>
>> I have  third party regular expression
>>
>>  self.pattern_main = 
>> re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
>> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')
>
> Also, whoever wrote this regular expression should be taken
> out and slapped with a wet fish, for it is abominable and
> unlikely to look much like what you actually want.

Here, take that fish and please, hit really hard !

**                 ;'-. 
     `;-._        )  '---.._
       >  `-.__.-'          `'.__
      /_.-'-._         _,   ^ ---)
      `       `'------/_.'----``


JM
**



From tfb at cley.com  Tue Jul 21 13:41:59 2009
From: tfb at cley.com (Tim Bradshaw)
Date: Tue, 21 Jul 2009 18:41:59 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <2009072118415916807-tfb@cleycom>

On 2009-07-19 19:31:36 +0100, Frank Buss <fb at frank-buss.de> said:

> (e.g. I
> don't know of a free modern and stable Lisp implemenation with
> mulithreading support for Windows, with a licence with which you can use it
> in closed source commercial programs, like you can do with Python).

Openmcl seems reasonably stable to me, is LLGPL-licensed, and runs on 
these platforms and Solaris x86.

It's kind of tragic, of course, that this kind of parasitic behaviour 
(will not consider a commercial product to use in your commercial 
system) has now become so common.



From robert.kern at gmail.com  Tue Jul 21 13:52:23 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Tue, 21 Jul 2009 12:52:23 -0500
Subject: clean way prepend an element to a numpy array
In-Reply-To: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
Message-ID: <h44v8m$ibu$1@ger.gmane.org>

On 2009-07-20 22:56, bdb112 wrote:
> If I want to add an element at the beginning of an array, it seems
> like I must make a list, insert in place, then make an array again.

the_array = numpy.concatenate([new_value, the_array])

You will want to ask numpy questions on the numpy mailing list.

   http://www.scipy.org/Mailing_Lists

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From rhodri at wildebst.demon.co.uk  Tue Jul 21 13:59:32 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 21 Jul 2009 18:59:32 +0100
Subject: Regular expression
In-Reply-To: <1AE4BD36-9955-4F80-9FBC-6DF62F529CC3@stuba.sk>
References: <200907211530.47704.peter.fodrek@stuba.sk>
	<op.uxfcgpzua8ncjz@gnudebst>
	<1AE4BD36-9955-4F80-9FBC-6DF62F529CC3@stuba.sk>
Message-ID: <op.uxfixifya8ncjz@gnudebst>

On Tue, 21 Jul 2009 17:12:53 +0100, Peter Fodrek <peter.fodrek at stuba.sk>  
wrote:

> 21.7.2009 v 17:39, Rhodri James:
>
>> On Tue, 21 Jul 2009 14:30:47 +0100, Peter Fodrek <peter.fodrek at stuba.sk 
>> > wrote:

[snipped for space]

>>> This handles text file  like
>>>
>>> // remark
>>> PL_OFF
>>> PARK
>>> FS
>>> MA  52.8806 ,  18.0914
>>> SS
>>> AD_W
>>> PL_ON
>>> C   52.3955 ,  -16.1511 ,  -90.0000
>>>
>>> It handles file correctly with two exceptions
>>>
>>> 1) omits ',' in the a output
>>
>> You don't do any output, so it's hard to correct that!
>
> for line
>
> C   52.3955 ,  -16.1511 ,  -90.0000
>
> it returns (as I remember)
>
> ('C', ' ', '52.3955', ' ', ' ', ' 16.1511', ' ', ' ','90.0')
>
> I was to get (number and positions of empty strings are not related to  
> me. I can add, remove then as you wish)
>
> ('C', ' ', '52.3955', ' ', ' ,', ' -16.1511', ' ', ' ,','-90.0')

If whitespace isn't an issue and the format really is as simple as
your example, you don't need the full power of a regular expression
here.  split() would do the trick:

     words = self.line.split()

will return what you want for that example.  It will produce different
(but more consistent) results than the regular expression for other lines,
though: for example,

MA  52.8806 , 18.0914

when put through the regular expression (if fixed for commas) would give  
you

('M', 'A', '  ', '52.8806', ' ', ',', ' ', '18.0914')

as against

['MA', '52.8806', ',', '18.0914']

> I use eval call in python to do format conversion, so just parsing is  
> problem

float() might be better than eval(), if you know for sure that you are
expecting floats.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From fred at bsdhost.net  Tue Jul 21 14:12:01 2009
From: fred at bsdhost.net (Fred C)
Date: Tue, 21 Jul 2009 11:12:01 -0700
Subject: setuptools question.
Message-ID: <AFD34FE4-50D2-4067-A292-7270A4A5C893@bsdhost.net>


I have a python program and when I install this program from the  
module home directory using setup.py everything works fine.

But easy_install fails with the following error, because I am trying  
to install some start up shell scripts into /etc/init.d

 > The package setup script has attempted to modify files on your system
 >that are not within the EasyInstall build area, and has been aborted.

Is there a way to use easy_install to install the start scripts into / 
etc/init.d. If not, what is the best way to install these scripts.

Thanks

-fred-




From hyugaricdeau at gmail.com  Tue Jul 21 14:13:35 2009
From: hyugaricdeau at gmail.com (Hyuga)
Date: Tue, 21 Jul 2009 11:13:35 -0700 (PDT)
Subject: are user defined classes hashable?
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net> 
	<mailman.3396.1248018412.8015.python-list@python.org>
	<373d6c69-6965-4a88-bdd2-8028ef850bf8@k6g2000yqn.googlegroups.com>
	<h43aik$oct$1@panix3.panix.com>
Message-ID: <b6ff0bbb-99f4-48eb-8334-8204a43f9d7f@w41g2000yqb.googlegroups.com>

On Jul 20, 10:53?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <373d6c69-6965-4a88-bdd2-8028ef850... at k6g2000yqn.googlegroups.com>,
>
> Hyuga ?<hyugaricd... at gmail.com> wrote:
>
> >Regardless, Nicolas's example can be applied to the class too:
>
> >>>> class Foo(object):
> > ? ?pass
>
> >>>> hash(Foo)
> >11443104
> >>>> id(Foo)
> >11443104
>
> >class objects are just objects of type 'type'.
>
> Not quite. ?They certainly default that way, but changing the metaclass
> changes a class's type::
>
> class M(type):
> ? ? pass
>
> class C(object):
> ? ? pass
>
> class C2(object):
> ? ? __metaclass__ = M
>
> print type(C)
> print type(C2)

Well, okay, you got me there.  But the OP wasn't asking about classes
with different metaclasses.  And besides, type(type(C2)) is still
type ;)


From tjreedy at udel.edu  Tue Jul 21 14:26:39 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Tue, 21 Jul 2009 14:26:39 -0400
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
Message-ID: <h4518v$pua$1@ger.gmane.org>

Nick Craig-Wood wrote:
>
> I tried it on a program I wrote to solve a puzzle (Rush Hour).
> (Actually it solves the meta-puzzle - trying to make the hardest
> possible Rush Hour puzzle.)
> 
> After a bit of twiddling (remove psyco and profiling) I got it to
> start compiling, but unfortunately it compiled for about an hour (in
> iterative type analysis..) used up 600 MB of RAM printing an '*' every
> 10 minutes or so then gave an error message and gave up.
> 
> Unfortunately I shut the window by accident, but the error message was
> something about not being able to resolve types I think with a list of
> 20 or so unresolved types.
> 
> Can you give a hint as to how I debug this?  I presume my program has
> some instances of non static types which is causing the problem, but
> it is going to be a very long debugging session if it takes me an hour
> each cycle ;-)
> 
> The program is about 700 lines of python (excluding comments).

Split it into pieces and compile each separately.
Recurse.

tjr



From tjreedy at udel.edu  Tue Jul 21 14:57:57 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Tue, 21 Jul 2009 14:57:57 -0400
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system()
	that  doesn't block gui event loops
In-Reply-To: <4a65f0d8$0$1599$742ec2ed@news.sonic.net>
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
	<4a65f0d8$0$1599$742ec2ed@news.sonic.net>
Message-ID: <h4533l$vre$1@ger.gmane.org>


> Ville Vainio wrote:
>> Has anyone implementing something like what the subject line
>> indicates?

Your subject line is so long that it is cut off even on my wide screen.
Better to repeat the question in the body.



From martin.hellwig at dcuktec.org  Tue Jul 21 15:05:55 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 21 Jul 2009 20:05:55 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>
	<fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>
	<3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>
Message-ID: <-vadnaHpJMoIjPvXnZ2dnUVZ8tli4p2d@bt.com>

David Adamo Jr. wrote:
> On Jul 21, 10:40 am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
> wrote:
>> sightseer wrote:
>>
>> <knip>
>>
>>> Error Installing Service: Access is Denied. (5)
>> <knip>
>> Are you trying to do this on windows vista?
>>
>> --
>> MPHhttp://blog.dcuktec.com
>> 'If consumed, best digested with added seasoning to own preference.'
> 
> Yeah, I was trying to do it on Vista. Someone has just helped me out.
> I had to deactivate User Account Control on Windows Vista...and now
> everything is rosy. Thanks guys.

No need to deactivate it, just right click on the command shell program 
and say run as administrator, than you can install the service via the 
command line.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From lukepadawan at gmail.com  Tue Jul 21 15:21:50 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Tue, 21 Jul 2009 16:21:50 -0300
Subject: List insertion cost
Message-ID: <4A66154E.1050200@gmail.com>

Hello,
I would like to know how much it costs to insert an element into a list 
using this operation:
a[2:2] = [ 1 ]
i. e, what is the complexity of the operation above (given that len(a) = n)?

Thanks.


From daniel at stutzbachenterprises.com  Tue Jul 21 15:35:55 2009
From: daniel at stutzbachenterprises.com (Daniel Stutzbach)
Date: Tue, 21 Jul 2009 14:35:55 -0500
Subject: List insertion cost
In-Reply-To: <4A66154E.1050200@gmail.com>
References: <4A66154E.1050200@gmail.com>
Message-ID: <eae285400907211235g7b458efbp73b171296ed901ec@mail.gmail.com>

On Tue, Jul 21, 2009 at 2:21 PM, Lucas P Melo <lukepadawan at gmail.com> wrote:

> I would like to know how much it costs to insert an element into a list
> using this operation:
> a[2:2] = [ 1 ]
> i. e, what is the complexity of the operation above (given that len(a) =
> n)?
>

O(n)

If you want O(log n), you can use the blist extension type from
http://pypi.python.org/pypi/blist/

--
Daniel Stutzbach, Ph.D.
President, Stutzbach Enterprises, LLC <http://stutzbachenterprises.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/4f40afaf/attachment.html>

From king.seth at gmail.com  Tue Jul 21 15:37:12 2009
From: king.seth at gmail.com (Seth)
Date: Tue, 21 Jul 2009 12:37:12 -0700 (PDT)
Subject: Pyserial and pyQt
Message-ID: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>


I have used pyserial in the past but this is my first experience with
pyQt.  I am using the Python xy package for windows current but might
move to linux.  I have a small device that is outputting a basic text
string.  I want to be able to read this string(from the comm port) and
update a text box and eventually a graph in pyQt.  I can't find any
documentation or tutorials on how to do this.  If anyone can point me
in the right direction or give me some tips I would be grateful.

Thanks,
Seth


From robert.kern at gmail.com  Tue Jul 21 15:43:41 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Tue, 21 Jul 2009 14:43:41 -0500
Subject: List insertion cost
In-Reply-To: <4A66154E.1050200@gmail.com>
References: <4A66154E.1050200@gmail.com>
Message-ID: <h455pe$h67$1@ger.gmane.org>

On 2009-07-21 14:21, Lucas P Melo wrote:
> Hello,
> I would like to know how much it costs to insert an element into a list
> using this operation:
> a[2:2] = [ 1 ]
> i. e, what is the complexity of the operation above (given that len(a) =
> n)?

O(n). Python lists are contiguous arrays in memory, and everything after the 
insertion point needs to be moved. Raymond Hettinger has a good talk about the 
implementation of Python lists and other container objects.

http://www.youtube.com/watch?v=hYUsssClE94
http://www.pycon.it/static/stuff/slides/core-python-containers-under-hood.ppt

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From lukepadawan at gmail.com  Tue Jul 21 16:47:26 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Tue, 21 Jul 2009 17:47:26 -0300
Subject: List insertion cost
In-Reply-To: <h455pe$h67$1@ger.gmane.org>
References: <4A66154E.1050200@gmail.com> <h455pe$h67$1@ger.gmane.org>
Message-ID: <4A66295E.9070004@gmail.com>

Robert Kern wrote:
> O(n). Python lists are contiguous arrays in memory, and everything 
> after the insertion point needs to be moved. Raymond Hettinger has a 
> good talk about the implementation of Python lists and other container 
> objects.
>
> http://www.youtube.com/watch?v=hYUsssClE94
> http://www.pycon.it/static/stuff/slides/core-python-containers-under-hood.ppt 
>
Thanks. :)



From ryniek90 at gmail.com  Tue Jul 21 16:55:18 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Tue, 21 Jul 2009 22:55:18 +0200
Subject: Changing the private variables content
In-Reply-To: <mailman.13181.1248195302.8014.python-list@python.org>
References: <mailman.13181.1248195302.8014.python-list@python.org>
Message-ID: <4A662B36.3010708@gmail.com>

Hi.
I'm writing some class, and decided to use inside private method and 
some private variables. While with method i haven't got any problem's 
with variables i have.
Maybe some example.
A class with private method and private variable:

"
 >>> class Secret(object):
    #
    def __init__(self):
        self._number = 1
    #
    def _secret(self):
        print self._number
    def showit(self):
        print "Secret number is:\n"
        self._secret()

 >>> sec = Secret()
 >>> sec.showit()
Secret number is:

1
 >>> sec._number
1
 >>> sec._number = 2
 >>> sec._number
2
 >>> sec._number += 3
 >>> sec._number
5
 >>>
"

As You can see, i made class with private method and private variable 
inside __init__ constructor. I've changed also the variable value, but 
outside class.
I've got problem with changing some variable value _inside__my_ class, 
which i'm writing.
I've searched over google, some tuts with topics about operations on 
private variables, but didn't found anything - only how to make them, 
but no how to assign new objects/override them with new content (and 
other advanced and helpful options).

If someone could help me, it would be great.

Thanks.


From davidj411 at gmail.com  Tue Jul 21 17:00:51 2009
From: davidj411 at gmail.com (davidj411)
Date: Tue, 21 Jul 2009 14:00:51 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
Message-ID: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>

I am using a recursive function to print the time and a few other
things on each pass. ( the function calculates size of file that is
being transferred and if not 100 % copied, it waits 20 secs and checks
again).

i would expect the time to be correct anytime it is used:

<--code below -->>
print time.strftime('%m-%d-%Y %H:%m:%S')
<--code above -->>

here is an example of what i am seeing:

16:07:16
16:07:36
16:07:56
16:07:16
16:07:36
16:07:56
16:07:16
16:07:36
16:07:56


From lukepadawan at gmail.com  Tue Jul 21 17:08:07 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Tue, 21 Jul 2009 18:08:07 -0300
Subject: Balanced binary tree implementation
Message-ID: <4A662E37.6090406@gmail.com>

Hello,

I would like to use a balanced binary tree implementation (preferably 
within some API).
Any hints about where I could find it?

I am looking for something that implements insertion, deletion, search 
and a special search that returns the lesser element bigger than a given 
key [1].

A nice possibility would be an extensible API that allows me to inherit 
its classes and to add operations myself.

Thanks in advance.

[1] Ex: 1 2 3 4 5 6 are elements of the bbt. If I use this operation 
given 4 as the parameter, the value returned would be 5.


From joncle at googlemail.com  Tue Jul 21 17:09:31 2009
From: joncle at googlemail.com (Jon Clements)
Date: Tue, 21 Jul 2009 14:09:31 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
Message-ID: <025efda8-0289-4d7d-a9e8-c90faa445c22@s31g2000yqs.googlegroups.com>

On 21 July, 22:00, davidj411 <davidj... at gmail.com> wrote:
> I am using a recursive function to print the time and a few other
> things on each pass. ( the function calculates size of file that is
> being transferred and if not 100 % copied, it waits 20 secs and checks
> again).
>
> i would expect the time to be correct anytime it is used:
>
> <--code below -->>
> print time.strftime('%m-%d-%Y %H:%m:%S')
> <--code above -->>
>
> here is an example of what i am seeing:
>
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56

I assume month, day and year are actually being output and that you've
removed it from your post.

Err, what else do you expect to happen if you're doing this
recursively?


From gherron at islandtraining.com  Tue Jul 21 17:14:44 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Tue, 21 Jul 2009 14:14:44 -0700
Subject: Changing the private variables content
In-Reply-To: <4A662B36.3010708@gmail.com>
References: <mailman.13181.1248195302.8014.python-list@python.org>
	<4A662B36.3010708@gmail.com>
Message-ID: <4A662FC4.2050804@islandtraining.com>

Ryniek90 wrote:
> Hi.
> I'm writing some class, and decided to use inside private method and 
> some private variables. While with method i haven't got any problem's 
> with variables i have.
> Maybe some example.
> A class with private method and private variable:
>
> "
> >>> class Secret(object):
>    #
>    def __init__(self):
>        self._number = 1
>    #
>    def _secret(self):
>        print self._number
>    def showit(self):
>        print "Secret number is:\n"
>        self._secret()
>
> >>> sec = Secret()
> >>> sec.showit()
> Secret number is:
>
> 1
> >>> sec._number
> 1
> >>> sec._number = 2
> >>> sec._number
> 2
> >>> sec._number += 3
> >>> sec._number
> 5
> >>>
> "
>
> As You can see, i made class with private method and private variable 
> inside __init__ constructor. I've changed also the variable value, but 
> outside class.
> I've got problem with changing some variable value _inside__my_ class, 
> which i'm writing.

Not sure this is what you are asking, but a method (which is how I 
interpret "_inside__my_ class") changes the value by normal assignment 
like this:

class Secret(object):
  ...
  def SetNumber(self,value):
    self._number = value

Is that what you were asking?


Gary Herron



> I've searched over google, some tuts with topics about operations on 
> private variables, but didn't found anything - only how to make them, 
> but no how to assign new objects/override them with new content (and 
> other advanced and helpful options).
>
> If someone could help me, it would be great.
>
> Thanks.



From sajmikins at gmail.com  Tue Jul 21 17:29:14 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 14:29:14 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
Message-ID: <146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>

On Jul 21, 5:00?pm, davidj411 <davidj... at gmail.com> wrote:
> I am using a recursive function to print the time and a few other
> things on each pass. ( the function calculates size of file that is
> being transferred and if not 100 % copied, it waits 20 secs and checks
> again).
>
> i would expect the time to be correct anytime it is used:
>
> <--code below -->>
> print time.strftime('%m-%d-%Y %H:%m:%S')
> <--code above -->>
>
> here is an example of what i am seeing:
>
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56

Your output doesn't match your format string:

In [1]: import time

In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
07-21-2009 17:07:16

There's no way to tell why your output times seem to repeat without
seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
%m:%S')" line.



From piet at cs.uu.nl  Tue Jul 21 17:38:43 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 23:38:43 +0200
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
Message-ID: <m263dln2cc.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:

>d> I am using a recursive function to print the time and a few other
>d> things on each pass. ( the function calculates size of file that is
>d> being transferred and if not 100 % copied, it waits 20 secs and checks
>d> again).

>d> i would expect the time to be correct anytime it is used:

>d> <--code below -->>
>d> print time.strftime('%m-%d-%Y %H:%m:%S')
>d> <--code above -->>

>d> here is an example of what i am seeing:

>d> 16:07:16
>d> 16:07:36
>d> 16:07:56
>d> 16:07:16
>d> 16:07:36
>d> 16:07:56
>d> 16:07:16
>d> 16:07:36
>d> 16:07:56

You probably meant: print time.strftime('%m-%d-%Y %H:%M:%S')
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jeanmichel at sequans.com  Tue Jul 21 17:42:41 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 21 Jul 2009 23:42:41 +0200
Subject: doted filenames in import statements
Message-ID: <4A663651.5020006@sequans.com>

Hi fellows,

I'd like to use the dynamic __import__ statement. It works pretty well 
with non dotted names, but I cannot figure how to make it work with 
dotted file paths.

example:

file = "/home/dsp/test.py"
test = __import__(file)

works like a charm

file = "/home/dsp/4.6.0.0/test.py"
test = __import__(file)
=> no module name blalalal found.

Any suggestion ? I tried multiple escape technics without any success.

JM



From joncle at googlemail.com  Tue Jul 21 17:52:57 2009
From: joncle at googlemail.com (Jon Clements)
Date: Tue, 21 Jul 2009 14:52:57 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<m263dln2cc.fsf@cs.uu.nl>
Message-ID: <577639e9-b64a-4a8e-8d90-b70ca491596b@18g2000yqa.googlegroups.com>

On 21 July, 22:38, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> davidj411 <davidj... at gmail.com> (d) wrote:
> >d> I am using a recursive function to print the time and a few other
> >d> things on each pass. ( the function calculates size of file that is
> >d> being transferred and if not 100 % copied, it waits 20 secs and checks
> >d> again).
> >d> i would expect the time to be correct anytime it is used:
> >d> <--code below -->>
> >d> print time.strftime('%m-%d-%Y %H:%m:%S')
> >d> <--code above -->>
> >d> here is an example of what i am seeing:
> >d> 16:07:16
> >d> 16:07:36
> >d> 16:07:56
> >d> 16:07:16
> >d> 16:07:36
> >d> 16:07:56
> >d> 16:07:16
> >d> 16:07:36
> >d> 16:07:56
>
> You probably meant: print time.strftime('%m-%d-%Y %H:%M:%S')
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

Good spot!


From davidj411 at gmail.com  Tue Jul 21 17:53:29 2009
From: davidj411 at gmail.com (davidj411)
Date: Tue, 21 Jul 2009 14:53:29 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
Message-ID: <dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>

On Jul 21, 5:29?pm, Simon Forman <sajmik... at gmail.com> wrote:
> On Jul 21, 5:00?pm, davidj411 <davidj... at gmail.com> wrote:
>
>
>
>
>
> > I am using a recursive function to print the time and a few other
> > things on each pass. ( the function calculates size of file that is
> > being transferred and if not 100 % copied, it waits 20 secs and checks
> > again).
>
> > i would expect the time to be correct anytime it is used:
>
> > <--code below -->>
> > print time.strftime('%m-%d-%Y %H:%m:%S')
> > <--code above -->>
>
> > here is an example of what i am seeing:
>
> > 16:07:16
> > 16:07:36
> > 16:07:56
> > 16:07:16
> > 16:07:36
> > 16:07:56
> > 16:07:16
> > 16:07:36
> > 16:07:56
>
> Your output doesn't match your format string:
>
> In [1]: import time
>
> In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
> 07-21-2009 17:07:16
>
> There's no way to tell why your output times seem to repeat without
> seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
> %m:%S')" line.

sorry, yes, i did manually filter the output.

here is the function:

def log_out(msg,servername='std.out'):
	print msg
	open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
+ time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')

on each pass, it should output the newer time (whether recursive or
not, right) ?


From clp2 at rebertia.com  Tue Jul 21 17:59:17 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 21 Jul 2009 14:59:17 -0700
Subject: doted filenames in import statements
In-Reply-To: <4A663651.5020006@sequans.com>
References: <4A663651.5020006@sequans.com>
Message-ID: <50697b2c0907211459w88c3e28y2a96811bd307233c@mail.gmail.com>

On Tue, Jul 21, 2009 at 2:42 PM, Jean-Michel
Pichavant<jeanmichel at sequans.com> wrote:
> Hi fellows,
>
> I'd like to use the dynamic __import__ statement. It works pretty well with
> non dotted names, but I cannot figure how to make it work with dotted file
> paths.
>
> example:
>
> file = "/home/dsp/test.py"
> test = __import__(file)
>
> works like a charm
>
> file = "/home/dsp/4.6.0.0/test.py"
> test = __import__(file)
> => no module name blalalal found.
>
> Any suggestion ? I tried multiple escape technics without any success.

You want the imp.load_module() function:
http://docs.python.org/library/imp.html#imp.load_module

__import__() only operates on module/package names. I'm not sure how
you even got it to work with a filename...

Cheers,
Chris
-- 
http://blog.rebertia.com


From rhodri at wildebst.demon.co.uk  Tue Jul 21 18:00:39 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 21 Jul 2009 23:00:39 +0100
Subject: Changing the private variables content
In-Reply-To: <4A662B36.3010708@gmail.com>
References: <mailman.13181.1248195302.8014.python-list@python.org>
	<4A662B36.3010708@gmail.com>
Message-ID: <op.uxft3d05a8ncjz@gnudebst>

On Tue, 21 Jul 2009 21:55:18 +0100, Ryniek90 <ryniek90 at gmail.com> wrote:

> Hi.
> I'm writing some class, and decided to use inside private method and  
> some private variables. While with method i haven't got any problem's  
> with variables i have.

There is no mechanism in Python that makes attributes truly private.
self._number is an attribute just like any other, the whole business
with _leading_underscores is purely a matter of convention.  If you
have an instance attribute or method with a leading underscore, you
know that using it or calling it isn't something you're supposed
to do outside its class, but nothing will stop you doing exactly that
if you're rude enough to try.

Does that help?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Tue Jul 21 18:01:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 00:01:35 +0200
Subject: Balanced binary tree implementation
References: <mailman.3486.1248210495.8015.python-list@python.org>
Message-ID: <m21vo9n1a8.fsf@cs.uu.nl>

>>>>> Lucas P Melo <lukepadawan at gmail.com> (LPM) wrote:

>LPM> Hello,
>LPM> I would like to use a balanced binary tree implementation (preferably
>LPM> within some API).
>LPM> Any hints about where I could find it?

>LPM> I am looking for something that implements insertion, deletion, search and
>LPM> a special search that returns the lesser element bigger than a given key
>LPM> [1].

>LPM> A nice possibility would be an extensible API that allows me to inherit its
>LPM> classes and to add operations myself.

>LPM> Thanks in advance.

>LPM> [1] Ex: 1 2 3 4 5 6 are elements of the bbt. If I use this operation given
>LPM> 4 as the parameter, the value returned would be 5.

http://newcenturycomputers.net/projects/rbtree.html (warning: see end of
page!)

http://pypi.python.org/pypi/rbtree/

http://pyavl.sourceforge.net/

http://code.activestate.com/recipes/576817/
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at mrabarnett.plus.com  Tue Jul 21 18:04:39 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 21 Jul 2009 23:04:39 +0100
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
In-Reply-To: <dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
Message-ID: <4A663B77.3020408@mrabarnett.plus.com>

davidj411 wrote:
> On Jul 21, 5:29 pm, Simon Forman <sajmik... at gmail.com> wrote:
>> On Jul 21, 5:00 pm, davidj411 <davidj... at gmail.com> wrote:
>>
>>
>>
>>
>>
>>> I am using a recursive function to print the time and a few other
>>> things on each pass. ( the function calculates size of file that is
>>> being transferred and if not 100 % copied, it waits 20 secs and checks
>>> again).
>>> i would expect the time to be correct anytime it is used:
>>> <--code below -->>
>>> print time.strftime('%m-%d-%Y %H:%m:%S')
>>> <--code above -->>
>>> here is an example of what i am seeing:
>>> 16:07:16
>>> 16:07:36
>>> 16:07:56
>>> 16:07:16
>>> 16:07:36
>>> 16:07:56
>>> 16:07:16
>>> 16:07:36
>>> 16:07:56
>> Your output doesn't match your format string:
>>
>> In [1]: import time
>>
>> In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
>> 07-21-2009 17:07:16
>>
>> There's no way to tell why your output times seem to repeat without
>> seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
>> %m:%S')" line.
> 
> sorry, yes, i did manually filter the output.
> 
> here is the function:
> 
> def log_out(msg,servername='std.out'):
> 	print msg
> 	open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
> + time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')
> 
> on each pass, it should output the newer time (whether recursive or
> not, right) ?

Maybe it does, but you were outputting the month ("07") instead of the
minutes; the seconds were changing.


From piet at cs.uu.nl  Tue Jul 21 18:11:38 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 00:11:38 +0200
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
Message-ID: <m2tz15lm91.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:
>>> 
>>> > <--code below -->>
>>> > print time.strftime('%m-%d-%Y %H:%m:%S')
>>> > <--code above -->>

>d> here is the function:

>d> def log_out(msg,servername='std.out'):
>d> 	print msg
>d> 	open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
>d> + time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')

>d> on each pass, it should output the newer time (whether recursive or
>d> not, right) ?

How come your strftime is now different from the first posting? Are you
cheating? 

If you want to ask a question about why your code is not working
properly there are a few important rules:

1. Copy and paste your code, and at least all relevant stuff (preferably
   a minimal example that shows the problem). *DO NOT RETYPE THE CODE*

2. Copy and paste the output. *DO NOT RETYPE THE OUTPUT*

3. Tell what the expected or desired output is.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Tue Jul 21 18:29:52 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 00:29:52 +0200
Subject: doted filenames in import statements
References: <mailman.3488.1248212574.8015.python-list@python.org>
Message-ID: <m2prbtllen.fsf@cs.uu.nl>

>>>>> Jean-Michel Pichavant <jeanmichel at sequans.com> (JP) wrote:

>JP> Hi fellows,
>JP> I'd like to use the dynamic __import__ statement. It works pretty well with
>JP> non dotted names, but I cannot figure how to make it work with dotted file
>JP> paths.

What is a dotted file path? Is that 4.6.0.0?

>JP> example:

>JP> file = "/home/dsp/test.py"
>JP> test = __import__(file)

>JP> works like a charm

That's not supposed to work. In older pythons it did work but that's a
bug. In newer pythons it doesn't. __import__ works on module names, not
on file names.

Python 2.6:

>>> spam = __import__('/Users/piet/TEMP/test.py', globals(), locals(), [], -1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: Import by filename is not supported.
>>> 

>JP> file = "/home/dsp/4.6.0.0/test.py"
>JP> test = __import__(file)
>JP> => no module name blalalal found.

>JP> Any suggestion ? I tried multiple escape technics without any success.

Rightly so.

I think the best would be to add the directory to sys.path 
sys.path.add('/home/dsp/4.6.0.0')
and then
__import__('test', ... ) 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From emile at fenx.com  Tue Jul 21 18:37:40 2009
From: emile at fenx.com (Emile van Sebille)
Date: Tue, 21 Jul 2009 15:37:40 -0700
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <7xiqho1c2i.fsf@ruckus.brouhaha.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>	<roy-362564.15092819072009@news.panix.com>	<h3vu2m$um2$1@ger.gmane.org>	<mailman.3407.1248038041.8015.python-list@python.org>
	<7xiqho1c2i.fsf@ruckus.brouhaha.com>
Message-ID: <h45g3h$g9r$1@ger.gmane.org>

On 7/19/2009 4:35 PM Paul Rubin said...
> Emile van Sebille <emile at fenx.com> writes:
>>>> Most people would still consider Solaris to be a "major platform".
>>> ?? I do not, but I have no idea what comes in 4th after the other
>>> three by whatever metric.
>> one metric calls fourth as the iPhone OS...
>> http://marketshare.hitslink.com/report.aspx?qprid=8...
> 
> That metric is clearly wrong.  The #1 platform OS platform in terms of
> number of units shipped is Javacard, which is in the SIM cards of
> billions of GSM phones.

Yes -- that location includes disclaimers on how they reach their 
conclusions.



From lists at cheimes.de  Tue Jul 21 18:48:40 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 22 Jul 2009 00:48:40 +0200
Subject: doted filenames in import statements
In-Reply-To: <50697b2c0907211459w88c3e28y2a96811bd307233c@mail.gmail.com>
References: <4A663651.5020006@sequans.com>
	<50697b2c0907211459w88c3e28y2a96811bd307233c@mail.gmail.com>
Message-ID: <h45gk8$hj6$1@ger.gmane.org>

Chris Rebert wrote:
> You want the imp.load_module() function:
> http://docs.python.org/library/imp.html#imp.load_module
> 
> __import__() only operates on module/package names. I'm not sure how
> you even got it to work with a filename...

It used to work with filenames but it was a bug. I guess several people
are swearing curses on me for removing this 'feature'. *g*

Christian



From ebonak at hotmail.com  Tue Jul 21 19:06:01 2009
From: ebonak at hotmail.com (Esmail)
Date: Tue, 21 Jul 2009 19:06:01 -0400
Subject: comments? storing a function in an object
In-Reply-To: <h425ks$fo7$1@ger.gmane.org>
References: <h425ks$fo7$1@ger.gmane.org>
Message-ID: <h45hko$k4h$1@ger.gmane.org>

Thanks *everyone* for your help, and sharing your knowledge.

I had no idea that Python functions could have user defined
attributes, and I may now not even need the object to wrap
my functions in.

Amazing what one can learn here .. thanks again!

Esmail



From nyamatongwe+thunder at gmail.com  Tue Jul 21 19:06:02 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Tue, 21 Jul 2009 23:06:02 GMT
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
Message-ID: <uRr9m.6558$ze1.5162@news-server.bigpond.net.au>

milanj:

> and all of them use native threads (python still use green threads ?)

   Python uses native threads.

   Neil


From david at boddie.org.uk  Tue Jul 21 19:24:32 2009
From: david at boddie.org.uk (David Boddie)
Date: Wed, 22 Jul 2009 01:24:32 +0200
Subject: Pyserial and pyQt
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
Message-ID: <h45inh$ofk$1@get-news01.get.basefarm.net>

On Tuesday 21 July 2009 21:37, Seth wrote:

> I have used pyserial in the past but this is my first experience with
> pyQt.  I am using the Python xy package for windows current but might
> move to linux.  I have a small device that is outputting a basic text
> string.  I want to be able to read this string(from the comm port) and
> update a text box and eventually a graph in pyQt.  I can't find any
> documentation or tutorials on how to do this.  If anyone can point me
> in the right direction or give me some tips I would be grateful.

It seems that someone has already asked a similar question on Stack
Overflow, though perhaps you should start with a simpler solution
and look at more advanced ones later:

  http://stackoverflow.com/questions/771988/pyqt4-and-pyserial

One starting point is this list of tutorials on the PyQt and PyKDE Wiki:

  http://www.diotavelli.net/PyQtWiki/Tutorials

Later, when you want to draw graphs, you might find PyQwt useful:

  http://pyqwt.sourceforge.net/

You may already be aware that there's also a mailing list for PyQt and
PyKDE:

  http://www.riverbankcomputing.com/pipermail/pyqt/

Another way to get answers to questions is to join the #pyqt IRC channel
at freenode.net:

  irc://irc.freenode.net/

David


From david.lyon at preisshare.net  Tue Jul 21 19:48:24 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 21 Jul 2009 19:48:24 -0400
Subject: setuptools question.
In-Reply-To: <AFD34FE4-50D2-4067-A292-7270A4A5C893@bsdhost.net>
References: <AFD34FE4-50D2-4067-A292-7270A4A5C893@bsdhost.net>
Message-ID: <21107bd58153b0a10d52ce5d3d9b70db@preisshare.net>

On Tue, 21 Jul 2009 11:12:01 -0700, Fred C <fred at bsdhost.net> wrote:
> I have a python program and when I install this program from the  
> module home directory using setup.py everything works fine.
> 
> But easy_install fails with the following error, because I am trying  
> to install some start up shell scripts into /etc/init.d
> 
>  > The package setup script has attempted to modify files on your system
>  >that are not within the EasyInstall build area, and has been aborted.
> 
> Is there a way to use easy_install to install the start scripts into / 
> etc/init.d. If not, what is the best way to install these scripts.

What package is it? what platform ?


From sajmikins at gmail.com  Tue Jul 21 19:59:21 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 16:59:21 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com> 
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
Message-ID: <16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com>

On Jul 21, 5:53?pm, davidj411 <davidj... at gmail.com> wrote:
> On Jul 21, 5:29?pm, Simon Forman <sajmik... at gmail.com> wrote:
>
>
>
> > On Jul 21, 5:00?pm, davidj411 <davidj... at gmail.com> wrote:
>
> > > I am using a recursive function to print the time and a few other
> > > things on each pass. ( the function calculates size of file that is
> > > being transferred and if not 100 % copied, it waits 20 secs and checks
> > > again).
>
> > > i would expect the time to be correct anytime it is used:
>
> > > <--code below -->>
> > > print time.strftime('%m-%d-%Y %H:%m:%S')
> > > <--code above -->>
>
> > > here is an example of what i am seeing:
>
> > > 16:07:16
> > > 16:07:36
> > > 16:07:56
> > > 16:07:16
> > > 16:07:36
> > > 16:07:56
> > > 16:07:16
> > > 16:07:36
> > > 16:07:56
>
> > Your output doesn't match your format string:
>
> > In [1]: import time
>
> > In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
> > 07-21-2009 17:07:16
>
> > There's no way to tell why your output times seem to repeat without
> > seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
> > %m:%S')" line.
>
> sorry, yes, i did manually filter the output.
>
> here is the function:
>
> def log_out(msg,servername='std.out'):
> ? ? ? ? print msg
> ? ? ? ? open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
> + time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')
>
> on each pass, it should output the newer time (whether recursive or
> not, right) ?

Well, as Piet van Oostrum pointed out, your problem in the first code
you posted was that you used '%m' rather than '%M' for the minutes.
(Good eye Van Oostrum!)  But now in this function you seem to have the
correct '%M' field.  Are you still having the same output after
changing that?


In any event, here's a rewritten version of that function that's a
little cleaner, FWIW.


from os.path import join
from time import strftime

format = '%m-%d-%Y %H:%M:%S'

def log_out(msg, servername='std.out'):
    print msg
    msg = "%s - %s %s\n" % (servername, strftime(format), msg)
    log_file = open(join(log_dir, servername + ".log"), 'a')
    try:
        log_file.write(msg)
    finally:
        log_file.close()


But why not just use the logging module?


From mail.to.daniel.platz at googlemail.com  Tue Jul 21 20:00:13 2009
From: mail.to.daniel.platz at googlemail.com (Daniel Platz)
Date: Tue, 21 Jul 2009 17:00:13 -0700 (PDT)
Subject: Fast reading and unpacking of binary data (struct module)
Message-ID: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>

Hi,

I have a Python newbie question about reading data from a binary file.
I have an huge binary file from an external program. I want to read
and process the data in this file in a reasonable time. It turns out
that the reading of the data itself and the processing do not need
most of the time. However, when using the read(bytes) method Python
returns a string representing the binary information in hex. This
string I have to "cast/translate" into a number (in my case a signed
short). For this I am using the method struct.unpack from the struct
module. This unpacking part of the program takes by far the most time.
Is there a way to speed this up or to do it the unpacking more
cleverly than with the struct module?

Thanks in advance.

With kind regards,

Daniel


From ronn.ross at gmail.com  Tue Jul 21 20:08:57 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Tue, 21 Jul 2009 19:08:57 -0500
Subject: trouble with minidom
Message-ID: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>

Hello I'm trying to read an xml file using minidome. The xml looks like:
<rootNode>
   <project>
      <name>myProj</name>
      <path>/here/</path>
   </project>
</rootNode>

My code looks like so:
from xml.dom.minidom import parse

dom = parse("myfile.xml")

for node in dom.getElementsByTagName("project'):
   print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,
node.childNodes[1])

Unfortunately, it returns 'nodeValue as none. I'm trying to read the value
out of the node fir example name: myProj. I haven't found much help in the
documentation. Can someone point me in the right direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/809e2fa2/attachment.html>

From gagsl-py2 at yahoo.com.ar  Tue Jul 21 20:18:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 21:18:42 -0300
Subject: Fast reading and unpacking of binary data (struct module)
References: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>
Message-ID: <op.uxf0hglwx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 21 Jul 2009 21:00:13 -0300, Daniel Platz  
<mail.to.daniel.platz at googlemail.com> escribi?:

> I have an huge binary file from an external program. I want to read
> and process the data in this file in a reasonable time. It turns out
> that the reading of the data itself and the processing do not need
> most of the time. However, when using the read(bytes) method Python
> returns a string representing the binary information in hex. This
> string I have to "cast/translate" into a number (in my case a signed
> short). For this I am using the method struct.unpack from the struct
> module. This unpacking part of the program takes by far the most time.
> Is there a way to speed this up or to do it the unpacking more
> cleverly than with the struct module?

Try creating a Struct object with your format and use its unpack() method.
http://docs.python.org/library/struct.html#struct-objects

If your format consists of just integers, probably an array is more  
efficient:
http://docs.python.org/library/array.html#array.array.fromfile

-- 
Gabriel Genellina



From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:18:44 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:18:44 +1200
Subject: tough-to-explain Python
In-Reply-To: <11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7cimf0F27u23eU1@mid.individual.net>
	<11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>
Message-ID: <7cn45nF28j1d4U1@mid.individual.net>

Simon Forman wrote:

> My understanding (so far) is that you (hope to) /derive/ correct code
> using formal logic, rather than writing code and then proving its
> soundness.

But to the extent you can rigorously formalise it,
all you've done is create Yet Another Programming
Language.

Which is fine, if you can come up with one that
works at a high enough level in some domain that
you can see just by looking that the program will
do what you want.

However, I suspect that you can't improve much on
what we've already got without restricting the
domain of applicability of the language. Otherwise,
you just shift the intellectual bottleneck from
writing a correct program to writing correct
specifications.

In the realm of programming language design, it's
been said that you can't eliminate complexity, all
you can do is push it around from one place to
another. I suspect something similar applies to
the difficulty of writing programs.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:28:39 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:28:39 +1200
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <87skgq8m7s.fsf@benfinney.id.au>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com>
	<87skgq8m7s.fsf@benfinney.id.au>
Message-ID: <7cn4obF286u4kU1@mid.individual.net>

Ben Finney wrote:
> My point was rather meant to imply that
> subclassing the built-in (immutable) string types was the best way to
> usefully get all their functionality

However, it would be difficult to do that without changing
all C code that deals with strings, including that in extension
modules.

That's because the existing string type stores the characters
in the string object itself. A mutable variant would have to
contain a pointer to a resizable memory block, and therefore
couldn't be used as a drop-in replacement by existing C
code that expects a string.

-- 
Greg


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 20:32:03 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 21:32:03 -0300
Subject: trouble with minidom
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
Message-ID: <op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 21 Jul 2009 21:08:57 -0300, Ronn Ross <ronn.ross at gmail.com>  
escribi?:

> Hello I'm trying to read an xml file using minidome. The xml looks like:
> <rootNode>
>    <project>
>       <name>myProj</name>
>       <path>/here/</path>
>    </project>
> </rootNode>
>
> My code looks like so:
> from xml.dom.minidom import parse
>
> dom = parse("myfile.xml")
>
> for node in dom.getElementsByTagName("project'):
>    print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,
> node.childNodes[1])
>
> Unfortunately, it returns 'nodeValue as none. I'm trying to read the  
> value
> out of the node fir example name: myProj. I haven't found much help in  
> the
> documentation. Can someone point me in the right direction?

Unless you have a specific reason to use the DOM interface (like having a  
masochistic mind), working with ElementTree usually is a lot easier:

py> import xml.etree.ElementTree as ET
py> xml = """<rootNode>
... <project>
...        <name>myProj</name>
...        <path>/here/</path>
... </project>
... </rootNode>"""
py> doc = ET.fromstring(xml)
py> for project in doc.findall('project'):
...   for child in project.getchildren():
...     print child.tag, child.text
...
name myProj
path /here/

-- 
Gabriel Genellina



From khanhqh2008i at gmail.com  Tue Jul 21 20:32:22 2009
From: khanhqh2008i at gmail.com (khanh le)
Date: Wed, 22 Jul 2009 07:32:22 +0700
Subject: Python
Message-ID: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>

do you have any materials about Python?
can you show me the link of Python or some books?
thanks a lots!

-- 
Regard!
Khanh
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/2749be50/attachment.html>

From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:35:18 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:35:18 +1200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <4a645b81$0$12974$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <7cn54pF28nv72U1@mid.individual.net>

William Dode wrote:

> I just tested it with a litle game, to find the places of horse on 
> a board 5x5. The result is :
> 
> cython avec malloc *int 18s

Posting benchmark times for Pyrex or Cython is pretty
meaningless without showing the exact code that was
used, since times can vary enormously depending on
how much you C-ify things.

-- 
Greg


From david.lyon at preisshare.net  Tue Jul 21 20:37:50 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 21 Jul 2009 20:37:50 -0400
Subject: Python
In-Reply-To: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
Message-ID: <00e687679e63af535bea6a4046f1df08@preisshare.net>

On Wed, 22 Jul 2009 07:32:22 +0700, khanh le <khanhqh2008i at gmail.com>
wrote:
> do you have any materials about Python?
> can you show me the link of Python or some books?

http://www.python.org/

> thanks a lots!

No problem. Have a nice day.


From casey.mcginty at gmail.com  Tue Jul 21 20:43:27 2009
From: casey.mcginty at gmail.com (Casey McGinty)
Date: Tue, 21 Jul 2009 14:43:27 -1000
Subject: SMTPlib and SMTPd Performance Issues
Message-ID: <ae3f58470907211743m68570739v6524b551190ea83a@mail.gmail.com>

Hi,

I just wanted mention a few workarounds I've come up with for the Python
SMTP modules in regards to performance.

Before I started, I was getting about 15MB/s while sending e-mail from
smtplib to smptd over a local connection. (i.e. both client/server running
on the same machine). After the following changes, I'm seeing around*220+MB/s
* (increase of 14x)

The source can be found here:
http://svn.python.org/view/python/trunk/Lib/smtplib.py?view=markup
http://svn.python.org/view/python/trunk/Lib/smtpd.py?view=markup

When sending e-mail through *smtpdlib*, the following method is called.

def quotedata(data):
    """Quote data for email.

    Double leading '.', and change Unix newline '\\n', or Mac '\\r' into
    Internet CRLF end-of-line.
    """
    return re.sub(r'(?m)^\.', '..',
        re.sub(r'(?:\r\n|\n|\r(?!\n))', CRLF, data))


As you can see there are two regular expressions parsing the data. If you
know that your message is formatted correctly to start with, then this step
is unnecessary.

When receiving e-mail through *smtpd*, the SMTPChannel class inherits from *
asynchat.async_chat*. The default recv buffer size for asynchat is 4K. This
can be too much overhead for high data throughput. The buffer size can be
increased with this code:

import asynchat
asynchat.async_chat.ac_in_buffer_size  = 1024*128
asynchat.async_chat.ac_out_buffer_size = 1024*128

The *smtpd.SMTP* class prcoesses data through the *smtpd.SMTPChannel* class.
There are a lot of debug statements in the module, like so:

print >> DEBUGSTREAM, 'Data:', repr(line)

By default, DEBUGSTREAM is a no-op, but that that doesn't prevent
repr(line) from being called. When variable, line, contains a large
email (multiple megabytes),
this debug step will really kill performance.

Secondly, the method *found_terminator* will also perform expensive
strings ops on the e-mail. Maybe its not possible to disable this
step, in all cases,
but for testing performance, you can override the method like so:

class QuickSMTPChannel( smtpd.SMTPChannel, object):
   def found_terminator(self):
      if (self._SMTPChannel__state == self.COMMAND or
            self._SMTPChannel__state != self.DATA):
         super(QuickSMTPChannel,self).found_terminator()
      else:
         data = smtpd.EMPTYSTRING.join(self._SMTPChannel__line)
         self._SMTPChannel__line = []
         status = self._SMTPChannel__server.process_message(
               self._SMTPChannel__peer, self._SMTPChannel__mailfrom,
               self._SMTPChannel__rcpttos, data)
         self._SMTPChannel__rcpttos = []
         self._SMTPChannel__mailfrom = None
         self._SMTPChannel__state = self.COMMAND
         self.set_terminator('\r\n')
         if not status:
             self.push('250 Ok')
         else:
             self.push(status

Thanks,

- Casey
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/30af3af7/attachment.html>

From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:47:35 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:47:35 +1200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
Message-ID: <7cn5rqF28emnnU1@mid.individual.net>

>>Steven D'Aprano <ste... at REMOVE.THIS.cybersource.com.au> writes:
>>
>>>Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing
>>>to do. It's the right thing to do if you're doing integer maths.

True, but the question is how best to decide whether the
programmer wants to do integer maths.

Deciding based on the types of the operands is okay in a
statically typed language. But it's asking for trouble in
a dynamically-typed language, especially where it's common
practice to use ints as a substitute for floats that
happen to have integer values.

EIBTI in this case.

-- 
Greg


From http  Tue Jul 21 21:07:24 2009
From: http (Paul Rubin)
Date: 21 Jul 2009 18:07:24 -0700
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7cimf0F27u23eU1@mid.individual.net>
	<11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>
	<7cn45nF28j1d4U1@mid.individual.net>
Message-ID: <7x4ot5bk4z.fsf@ruckus.brouhaha.com>

greg <greg at cosc.canterbury.ac.nz> writes:
> However, I suspect that you can't improve much on what we've already
> got without restricting the domain of applicability of the
> language. Otherwise, you just shift the intellectual bottleneck from
> writing a correct program to writing correct specifications.

Really, it's easier to write specifications.  They're a level of
abstraction away from the implementation.  Think of a sorting
function that operates on a list a1,a2...a_n.  The sorting algorithm
might be some fiendishly clever, hyper-optimized hybrid of quicksort,
heapsort, timsort, burstsort, and 52-pickup.  It might be thousands
of lines of intricate code that looks like it could break at the
slightest glance.  The specification simply says the output
has the property a1<=a2<=...<=a_n.  That is a lot easier to
say.  If you can then prove that the program satisfies the
specification, you are far better off than if you have some
super-complex pile of code that appears to sort when you test
it, but has any number of possible edge cases that you didn't
figure out needed testing.  It's like the difference between
stating a mathematical theorem (like the four-color theorem)
and proving it.


From pjb at informatimago.com  Tue Jul 21 21:19:19 2009
From: pjb at informatimago.com (Pascal J. Bourguignon)
Date: Wed, 22 Jul 2009 03:19:19 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<2009072118415916807-tfb@cleycom>
Message-ID: <87my6xa50o.fsf@galatea.local>

Tim Bradshaw <tfb at cley.com> writes:

> On 2009-07-19 19:31:36 +0100, Frank Buss <fb at frank-buss.de> said:
>
>> (e.g. I
>> don't know of a free modern and stable Lisp implemenation with
>> mulithreading support for Windows, with a licence with which you can use it
>> in closed source commercial programs, like you can do with Python).
>
> Openmcl seems reasonably stable to me, is LLGPL-licensed, and runs on
> these platforms and Solaris x86.
>
> It's kind of tragic, of course, that this kind of parasitic behaviour
> (will not consider a commercial product to use in your commercial
> system) has now become so common.

GPL.

-- 
__Pascal Bourguignon__


From dstanek at dstanek.com  Tue Jul 21 22:05:46 2009
From: dstanek at dstanek.com (David Stanek)
Date: Tue, 21 Jul 2009 22:05:46 -0400
Subject: Changing the private variables content
In-Reply-To: <op.uxft3d05a8ncjz@gnudebst>
References: <mailman.13181.1248195302.8014.python-list@python.org>
	<4A662B36.3010708@gmail.com> <op.uxft3d05a8ncjz@gnudebst>
Message-ID: <de32cc030907211905t570aba18wcd60ecce07c3d873@mail.gmail.com>

On Tue, Jul 21, 2009 at 6:00 PM, Rhodri
James<rhodri at wildebst.demon.co.uk> wrote:
> On Tue, 21 Jul 2009 21:55:18 +0100, Ryniek90 <ryniek90 at gmail.com> wrote:
>
>> Hi.
>> I'm writing some class, and decided to use inside private method and some
>> private variables. While with method i haven't got any problem's with
>> variables i have.
>
> There is no mechanism in Python that makes attributes truly private.
> self._number is an attribute just like any other, the whole business
> with _leading_underscores is purely a matter of convention. ?If you
> have an instance attribute or method with a leading underscore, you
> know that using it or calling it isn't something you're supposed
> to do outside its class, but nothing will stop you doing exactly that
> if you're rude enough to try.
>

Doubling the _ will give you a little more privacy. It really just
mangles the attribute name, but it close to what you want.

I just use a _single_under to tell other programmers that they
shouldn't be accessing that attribute directly. To my knowledge
nothing bad has happened because things are public and using the
__double_under makes testing a little harder.

  >>> class C(object):
  ...     def __init__(self):
  ...         self.__x = 0
  ...
  >>> c = C()
  >>> c.__x
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  AttributeError: 'C' object has no attribute '__x'
  >>> c._C__x
  0


-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 22:18:26 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 23:18:26 -0300
Subject: Python
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
	<00e687679e63af535bea6a4046f1df08@preisshare.net>
Message-ID: <op.uxf500qnx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 21 Jul 2009 21:37:50 -0300, David Lyon <david.lyon at preisshare.net>  
escribi?:
> On Wed, 22 Jul 2009 07:32:22 +0700, khanh le <khanhqh2008i at gmail.com>
> wrote:

>> do you have any materials about Python?
>> can you show me the link of Python or some books?
>
> http://www.python.org/

Also see http://wiki.python.org/moin/BeginnersGuide

-- 
Gabriel Genellina



From prateekkakirwar at gmail.com  Wed Jul 22 00:42:39 2009
From: prateekkakirwar at gmail.com (Prateek)
Date: Tue, 21 Jul 2009 21:42:39 -0700 (PDT)
Subject: Python
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com> 
	<00e687679e63af535bea6a4046f1df08@preisshare.net>
	<mailman.3503.1248229122.8015.python-list@python.org>
Message-ID: <6281cf33-8ab6-4ff6-a2c5-a9fa1e66d368@m7g2000prd.googlegroups.com>

Chk dis out ...

http://www.swaroopch.com/notes/Python

It's gr8 guide for beginners

Cheers!!!
Prateek


From gagsl-py2 at yahoo.com.ar  Wed Jul 22 01:02:55 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 02:02:55 -0300
Subject: Detect target name in descriptor __set__ method
Message-ID: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>

I have a class attribute 'foo' which is a data descriptor. I create an  
instance of such class. When I say instance.foo = value, the descriptor  
__set__ method is called. Is there any way to obtain the name being  
assigned to? ('foo' in this example). That is, I want to know the target  
name for the assignment that triggered the __set__ method call.

class descriptor(object):
   def __get__(self, instance, owner):
     print 'descriptor.__get__ self=%r instance=%r owner=%r' % (
       self, instance, owner)
     return self

   def __set__(self, instance, value):
     # I want to know the *name* this value is being assigned to
     print 'descriptor.__set__ self=%r instance=%r value=%r' % (
       self, instance, value)

   def __delete__(self, instance):
     print 'descriptor.__delete__ self=%r instance=%r' % (
       self, instance)

class X(object):
   foo = descriptor()

x = X()
x.foo = "value"


I can obtain the name descriptor() was assigned to at the time the X class  
was defined, using a custom metaclass:


class Meta(type):
   def __new__(meta, name, bases, dict):
     for key,value in dict.iteritems():
       if isinstance(value, descriptor):
         value.name = key
     return type.__new__(meta, name, bases, dict)

class Y(object):
   __metaclass__ = Meta
   foo = descriptor()

y = Y()
print y.foo.name # prints 'foo'


This is good enough for me (assuming no one modifies the class after  
defining it, no two names refer to the same descriptor, no two classes  
share the same descriptor instance...). But I would like to use a more  
direct/robust approach, if available.

Any ideas?

-- 
Gabriel Genellina



From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Wed Jul 22 01:09:35 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Wed, 22 Jul 2009 01:09:35 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
Message-ID: <h467aq$mfg$1@news.eternal-september.org>

On 2009-07-21 19:06:02 -0400, Neil Hodgson 
<nyamatongwe+thunder at gmail.com> said:

>    Python uses native threads.

So it can be teh-slowness on all ur cores!

<http://shootout.alioth.debian.org/u64q/benchmark.php?test=nbody&lang=all>

The global interpreter lock doesn't help much either.

-- 
Raffael Cavallaro



From wolfgang at rohdewald.de  Wed Jul 22 01:24:21 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Wed, 22 Jul 2009 07:24:21 +0200
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <200907220724.21185.wolfgang@rohdewald.de>

On Wednesday 22 July 2009, Gabriel Genellina wrote:
> x = X()
> x.foo = "value"

del x.foo

-- 
Wolfgang


From wolfgang at rohdewald.de  Wed Jul 22 01:28:11 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Wed, 22 Jul 2009 07:28:11 +0200
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <200907220724.21185.wolfgang@rohdewald.de>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<200907220724.21185.wolfgang@rohdewald.de>
Message-ID: <200907220728.11536.wolfgang@rohdewald.de>

On Wednesday 22 July 2009, Wolfgang Rohdewald wrote:
> On Wednesday 22 July 2009, Gabriel Genellina wrote:
> > x = X()
> > x.foo = "value"
>
> del x.foo

sorry, was not yet quite awaken - I read "delete target name"
instead of "detect target name"

-- 
Wolfgang


From gagsl-py2 at yahoo.com.ar  Wed Jul 22 01:43:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 02:43:07 -0300
Subject: Regular exprssion for IRC messages
References: <e4de9e30907170959y4fcae9d3v8e26d9fd94e76f4f@mail.gmail.com>
Message-ID: <op.uxgfh5mex6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 13:59:47 -0300, nohics nohics <nohics at gmail.com>  
escribi?:

> When an IRC client receive a messages, this message in in a special  
> format
> defined here: Message format in pseudo
> BNF<http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1>(
>
> I want to transforme the message format defined in the irc protocole in  
> the
> last link, to a regular expression to get the nickname, the username, the
> host, the commad, it's arguments if exist, and the message after ":"

You may want to use the pyparsing module instead of a monstruous and  
unmantainable regular expression:

http://pyparsing.wikispaces.com/

-- 
Gabriel Genellina



From jhinak.sen at gmail.com  Wed Jul 22 02:28:27 2009
From: jhinak.sen at gmail.com (jhinak sen)
Date: Wed, 22 Jul 2009 11:58:27 +0530
Subject: plotting graph from another file
Message-ID: <3d4ff96c0907212328q211801b4tc7a86986a9c35c25@mail.gmail.com>

hello..

i want to plot a distribution graph for following data:
*elements:               number of occurance:
   a                            2
   b                            4
   c                            1
   d                            9
   e                            3*

( this a simple version)

the data is in a file , say abc.txt

how can i call/import the text file and draw an appropriate distribution
graph in python  ?
can it be done using matplotlib ?

if yes , please give me the code for plotting the  importing the text file
and plotting the graph.

thanx

jhinak
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/7f93c95a/attachment.html>

From hendrik at microcorp.co.za  Wed Jul 22 02:36:29 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 22 Jul 2009 08:36:29 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
Message-ID: <200907220836.30064.hendrik@microcorp.co.za>

On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
> On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
>
> wrote:
> > [snip] We
> > understand that lists are mutable and tuples are not, but we're a
> > little lost as to why the two were kept separate from the start. They
> > both perform a very similar job as far as we can tell.
>
> My guess is that it was probably for optimization reasons long ago.
> I've never heard a *good* reason why Python needs both.

The good reason is the immutability, which lets you use
a tuple as a dict key.  

- Hendrik


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 22 02:40:16 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 22 Jul 2009 06:40:16 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86skgr0yjn.fsf@gmail.com>
Message-ID: <pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au>

On Tue, 21 Jul 2009 00:39:24 +0200, Niels L. Ellegaard wrote:

> Phillip B Oldham <phillip.oldham at gmail.com> writes:
> 
>> We often find we need to do manipulations like the above without
>> changing the order of the original list, and languages like JS allow
>> this. We can't work out how to do this in python though, other than
>> duplicating the list, sorting, reversing, then discarding.

I think Phillip is confused if he thinks that other languages can sort a 
list without modifying or duplicating the original. If you don't 
duplicate the list, how can you sort it without modifying the original? 
The only difference is whether the language makes the duplicate for you, 
or expects you to do it yourself.


> If you just want a one-liner, and you don't care about speed you can do
> the following (but I don't think this is considered best practice)
> 
>>>> x = [2,1,3]
>>>> print list(sorted(x))

The call to list is redundant, as sorted() already creates a list.


But that's the wrong solution to the problem. The OP wants the largest 
(or smallest) item, which he expects to get by sorting, then grabbing the 
first element:

sorted(alist)[0]

That requires sorting the entire list, only to throw away everything 
except the first item. A better solution is to use min() and max(), 
neither of which sort the list, so they are much faster.



-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 22 02:45:54 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 22 Jul 2009 06:45:54 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
Message-ID: <pan.2009.07.22.06.45.53@REMOVE.THIS.cybersource.com.au>

On Tue, 21 Jul 2009 06:49:59 -0700, Inky 788 wrote:

> On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com> wrote:
>> [snip] We
>> understand that lists are mutable and tuples are not, but we're a
>> little lost as to why the two were kept separate from the start. They
>> both perform a very similar job as far as we can tell.
> 
> My guess is that it was probably for optimization reasons long ago. I've
> never heard a *good* reason why Python needs both.

Suppose you could do this:

key = [1, 2]
adict = {key: 'x', [1, 1]: 'y'}

This would work as expected:

adict[ [1, 2] ]
=> returns 'x'

adict[ [1, 1] ]
=> returns 'y'

But what happens if you mutate the key?

key[1] = 0
adict[ [1, 2] ]
=> raises KeyError

Okay, that's bad. What's even worse is this:

key[1] = 1
adict[ [1, 1] ]
=> should it return 'x' or 'y'?


The solution is to disallow mutable objects like lists from being used as 
keys in dicts, and to allow immutable list-like tuples instead.



-- 
Steven


From clp2 at rebertia.com  Wed Jul 22 02:46:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 21 Jul 2009 23:46:13 -0700
Subject: plotting graph from another file
In-Reply-To: <3d4ff96c0907212328q211801b4tc7a86986a9c35c25@mail.gmail.com>
References: <3d4ff96c0907212328q211801b4tc7a86986a9c35c25@mail.gmail.com>
Message-ID: <50697b2c0907212346t3673b2a0rc5669bf7663bc4c6@mail.gmail.com>

On Tue, Jul 21, 2009 at 11:28 PM, jhinak sen<jhinak.sen at gmail.com> wrote:
> hello..
>
> i want to plot a distribution graph for following data:
> elements:?????????????? number of occurance:
> ?? a ?? ? ? ? ? ? ? ? ? ? ? ? ? 2
> ?? b??????????????????????????? 4
> ?? c??????????????????????????? 1
> ?? d??????????????????????????? 9
> ?? e??????????????????????????? 3
>
> ( this a simple version)
>
> the data is in a file , say abc.txt
>
> how can i call/import the text file and draw an appropriate distribution
> graph in python? ?
> can it be done using matplotlib ?
>
> if yes , please give me the code for plotting the? importing the text file
> and plotting the graph.

Given matplot's versatility, I would presume with high likelihood that
matplot could make such a chart.

However, the purpose of this mailinglist is *not* to do people's
job/work/homework for them for free.
I would suggest you first *attempt* coding a solution yourself.
If you run into trouble, read http://catb.org/~esr/faqs/smart-questions.html
Then ask a more specific question on the mailinglist.

Best of luck.

Regards,
Chris

From bearophileHUGS at lycos.com  Wed Jul 22 02:48:55 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 21 Jul 2009 23:48:55 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
Message-ID: <861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>

greg:
> Posting benchmark times for Pyrex or Cython is pretty
> meaningless without showing the exact code that was
> used, since times can vary enormously depending on
> how much you C-ify things.

Was this link, shown by William, not enough?
http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1

Bye,
bearophile


From greg at cosc.canterbury.ac.nz  Wed Jul 22 02:51:22 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 18:51:22 +1200
Subject: clean way prepend an element to a numpy array
In-Reply-To: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
Message-ID: <7cnr5tF28183hU1@mid.individual.net>

bdb112 wrote:

> I saw this interest syntax on this site
> x[:0]=0
> 
> I guess that is cute, but could be confusing....(and doesn't work)

It does if you use an array of the appropriate
type on the right hand side:

   a[:0] = array('i', [0])

-- 
Greg


From walkraft at gmail.com  Wed Jul 22 02:59:34 2009
From: walkraft at gmail.com (casebash)
Date: Tue, 21 Jul 2009 23:59:34 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com> 
	<87skgq8m7s.fsf@benfinney.id.au> <7cn4obF286u4kU1@mid.individual.net>
Message-ID: <cfcfdcf6-edca-42fe-a008-e1d55eed5f9e@g1g2000pra.googlegroups.com>

Thanks all for your advice. I'm not actually going to use the mutable
string right at the moment, but I thought I might in the future and I
was just curious if it existed. I suppose a list of characters is
close enough for most purposes.

On Jul 22, 10:28?am, greg <g... at cosc.canterbury.ac.nz> wrote:
> Ben Finney wrote:
> > My point was rather meant to imply that
> > subclassing the built-in (immutable)stringtypes was the best way to
> > usefully get all their functionality
>
> However, it would be difficult to do that without changing
> all C code that deals with strings, including that in extension
> modules.
>
> That's because the existingstringtype stores the characters
> in thestringobject itself. Amutablevariant would have to
> contain a pointer to a resizable memory block, and therefore
> couldn't be used as a drop-in replacement by existing C
> code that expects astring.
>
> --
> Greg



From timr at probo.com  Wed Jul 22 03:09:07 2009
From: timr at probo.com (Tim Roberts)
Date: Wed, 22 Jul 2009 00:09:07 -0700
Subject: win32api install problem
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
Message-ID: <8led65544idaf3630nk21rjij030aj4s4k@4ax.com>

Gerry <gerard.blais at gmail.com> wrote:

>I'm running Python 2.6 under XP.
>
>I've installed Windows 32 extensions for Python 2.6 version 1.4
>(pywin32-214.win32-py2.6.exe).
>
>But If I try to import win32api, I get:
>
>  File "C:\python_projects\euler\driveletters.py", line 1, in <module>
>    import win32api
>ImportError: DLL load failed: The specified module could not be found.
>
>\Python26\Lib\site-packages has:
>
>03/23/2009  08:35 AM    <DIR>          win32
>07/20/2009  09:08 AM    <DIR>          win32com
>02/18/2009  01:21 PM    <DIR>          win32comext
>
>Can anyone offer a suggestion?

It is very unusual that those three directories should have different
creation dates.  Normally, all three would have the same date and time,
from whenever you ran the installer.

I would suggest that you go into Add and Remove Programs, uninstall
pywin32, and run the installer again.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From dtgeadamo at yahoo.com  Wed Jul 22 03:13:49 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Wed, 22 Jul 2009 00:13:49 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com> 
	<fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>
	<3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>
	<-vadnaHpJMoIjPvXnZ2dnUVZ8tli4p2d@bt.com>
Message-ID: <bb7706f8-8c83-4476-9bff-cebf3c8b9bd3@c1g2000yqi.googlegroups.com>

On Jul 21, 8:05?pm, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
wrote:
> David Adamo Jr. wrote:
> > On Jul 21, 10:40 am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
> > wrote:
> >> sightseer wrote:
>
> >> <knip>
>
> >>> Error Installing Service: Access is Denied. (5)
> >> <knip>
> >> Are you trying to do this on windows vista?
>
> >> --
> >> MPHhttp://blog.dcuktec.com
> >> 'If consumed, best digested with added seasoning to own preference.'
>
> > Yeah, I was trying to do it on Vista. Someone has just helped me out.
> > I had to deactivate User Account Control on Windows Vista...and now
> > everything is rosy. Thanks guys.
>
> No need to deactivate it, just right click on the command shell program
> and say run as administrator, than you can install the service via the
> command line.
>
> --
> MPHhttp://blog.dcuktec.com
> 'If consumed, best digested with added seasoning to own preference.'

Thanks MPH


From milesck at umich.edu  Wed Jul 22 03:21:06 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 22 Jul 2009 03:21:06 -0400
Subject: trouble with minidom
In-Reply-To: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
Message-ID: <A2032940-684F-4376-8CDA-6C1595F980DB@umich.edu>

On Jul 21, 2009, at 8:08 PM, Ronn Ross wrote:

> Hello I'm trying to read an xml file using minidome. The xml looks  
> like:
> <rootNode>
>    <project>
>       <name>myProj</name>
>       <path>/here/</path>
>    </project>
> </rootNode>
>
> My code looks like so:
> from xml.dom.minidom import parse
>
> dom = parse("myfile.xml")
>
> for node in dom.getElementsByTagName("project'):
>    print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,  
> node.childNodes[1])
>
> Unfortunately, it returns 'nodeValue as none. I'm trying to read the  
> value out of the node fir example name: myProj. I haven't found much  
> help in the documentation. Can someone point me in the right  
> direction?

Two issues:

In your example XML file, the first child node of the project Element  
is the Text node containing the whitespace between the <project> and  
<name> tags.  node.childNodes[0] will select that whitespace node.

The nodeValue of an Element is null (None).  In order to get the text  
contents of an element, you must get the nodeValue of the Text child  
node of the Element.

Like Gabriel, I would recommend using an XML library with a more  
concise API than the W3C DOM (I like lxml.objectify).  But if you  
stick with xml.dom, use the specification as a reference:

http://www.w3.org/TR/REC-DOM-Level-1/


From hv at tbz-pariv.de  Wed Jul 22 04:05:19 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Wed, 22 Jul 2009 10:05:19 +0200
Subject: Workflow Libraries (DB vs Code)
In-Reply-To: <7cm6kmF26g9srU1@mid.uni-berlin.de>
References: <7cm1ifF28jmnhU1@mid.individual.net>
	<7cm6kmF26g9srU1@mid.uni-berlin.de>
Message-ID: <7cnvi0F28qk9aU1@mid.individual.net>

Diez B. Roggisch schrieb:
> Thomas Guettler wrote:
> 
>> Hi,
>>
>> I need to write some simple workflows with web interface.
>>
>> For the web stuff I will use django, but I am not sure how
>> to do the workflow part.
> 
> Did you consider using OpenERP? It comes with a web-frontend
> (TG1.0.8-based), but also offers a XMLRPC-server to connect to, so using it
> from within django shouldn't be any difficult.
> 
> Workflow-definitions are stored in the DB, and can be generated visually,
> not sure if they have to though.

Thank you for this hint. OpenERP seems well done.

But the licence is GPL and the dependency is too big. But I will have a look
at how they did it.

  Thomas


-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From joncle at googlemail.com  Wed Jul 22 04:21:49 2009
From: joncle at googlemail.com (Jon Clements)
Date: Wed, 22 Jul 2009 01:21:49 -0700 (PDT)
Subject: Regular exprssion for IRC messages
References: <e4de9e30907170959y4fcae9d3v8e26d9fd94e76f4f@mail.gmail.com> 
	<mailman.3509.1248241400.8015.python-list@python.org>
Message-ID: <4e59a9a3-f565-4042-9016-5192b8ff8247@c29g2000yqd.googlegroups.com>

On 22 July, 06:43, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> En Fri, 17 Jul 2009 13:59:47 -0300, nohics nohics <noh... at gmail.com> ?
> escribi?:
>
> > When an IRC client receive a messages, this message in in a special ?
> > format
> > defined here: Message format in pseudo
> > BNF<http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1>(
>
> > I want to transforme the message format defined in the irc protocole in ?
> > the
> > last link, to a regular expression to get the nickname, the username, the
> > host, the commad, it's arguments if exist, and the message after ":"
>
> You may want to use the pyparsing module instead of a monstruous and ?
> unmantainable regular expression:
>
> http://pyparsing.wikispaces.com/
>
> --
> Gabriel Genellina

Alternatively, if IIRC, the twisted framework has an IRC client, which
automatically parses server messages.


From dtgeadamo at yahoo.com  Wed Jul 22 04:27:52 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Wed, 22 Jul 2009 01:27:52 -0700 (PDT)
Subject: Ideas for problem with chat server application!
Message-ID: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>

I developed a chat application with an attendant chat server.
Everything is working fine. The issue now is the fact that whenever
the chat server goes down (for instance, the server system shuts down
as a result of power failure or some other problem), by the time the
server system come back on, the chat server would have to be restarted
manually.

I believe (and I know) it is more appropriate for the chat server
application to restart itself when the computer comes back on (and of
course regardless of who is logged in and of course, even before
anyone logs in). I have a batch file that executes the chat server. My
attempt was to create a windows service that start automatically and
runs this batch file using a Network Service account on the server
system. Although, I'm having a hard time with this (temporarily), I
would love to ask if there are any alternatives to using a windows
service. Suggestions are highly appreciated.


From joncle at googlemail.com  Wed Jul 22 04:31:13 2009
From: joncle at googlemail.com (Jon Clements)
Date: Wed, 22 Jul 2009 01:31:13 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <mailman.3504.1248238988.8015.python-list@python.org>
Message-ID: <3cb5f960-16f7-4fc6-841f-d0706f0e1d0a@s31g2000yqs.googlegroups.com>

On 22 July, 06:02, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> I have a class attribute 'foo' which is a data descriptor. I create an ?
> instance of such class. When I say instance.foo = value, the descriptor ?
> __set__ method is called. Is there any way to obtain the name being ?
> assigned to? ('foo' in this example). That is, I want to know the target ?
> name for the assignment that triggered the __set__ method call.
>
> class descriptor(object):
> ? ?def __get__(self, instance, owner):
> ? ? ?print 'descriptor.__get__ self=%r instance=%r owner=%r' % (
> ? ? ? ?self, instance, owner)
> ? ? ?return self
>
> ? ?def __set__(self, instance, value):
> ? ? ?# I want to know the *name* this value is being assigned to
> ? ? ?print 'descriptor.__set__ self=%r instance=%r value=%r' % (
> ? ? ? ?self, instance, value)
>
> ? ?def __delete__(self, instance):
> ? ? ?print 'descriptor.__delete__ self=%r instance=%r' % (
> ? ? ? ?self, instance)
>
> class X(object):
> ? ?foo = descriptor()
>
> x = X()
> x.foo = "value"
>
> I can obtain the name descriptor() was assigned to at the time the X class ?
> was defined, using a custom metaclass:
>
> class Meta(type):
> ? ?def __new__(meta, name, bases, dict):
> ? ? ?for key,value in dict.iteritems():
> ? ? ? ?if isinstance(value, descriptor):
> ? ? ? ? ?value.name = key
> ? ? ?return type.__new__(meta, name, bases, dict)
>
> class Y(object):
> ? ?__metaclass__ = Meta
> ? ?foo = descriptor()
>
> y = Y()
> print y.foo.name # prints 'foo'
>
> This is good enough for me (assuming no one modifies the class after ?
> defining it, no two names refer to the same descriptor, no two classes ?
> share the same descriptor instance...). But I would like to use a more ?
> direct/robust approach, if available.
>
> Any ideas?
>
> --
> Gabriel Genellina

>>> class Test:
	def __setattr__(self, what, value):
		print what, value


>>> t = Test()
>>> t.foo = 'x'
foo x

Is that what you're after?

Jon.


From phillip.oldham at gmail.com  Wed Jul 22 05:27:56 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Wed, 22 Jul 2009 02:27:56 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
Message-ID: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>

I understand that there are a number of MapReduce frameworks/tools
that play nicely with Python (Disco, Dumbo/Hadoop), however these have
"large" dependencies (Erlang/Java). Are there any MapReduce frameworks/
tools which are either pure-Python, or play nicely with Python but
don't require the Java/Erlang runtime environments?


From user at example.net  Wed Jul 22 06:03:44 2009
From: user at example.net (superpollo)
Date: Wed, 22 Jul 2009 12:03:44 +0200
Subject: binary literal
Message-ID: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>

hello clp.

i can insert a hex value for a character literal in a string:

 >>> stuff = "\x45"
 >>> print stuff
E
 >>>

can i do something like the above, but using a *binary* number? (e.g. 
00101101 instead of 45) ?

bye


From pmarti at warp.es  Wed Jul 22 06:24:22 2009
From: pmarti at warp.es (=?ISO-8859-1?Q?Pablo_Mart=ED_Gamboa?=)
Date: Wed, 22 Jul 2009 12:24:22 +0200
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <53a2f8770907220324m445c3004s9c844176255eaf46@mail.gmail.com>

2009/7/22 superpollo <user at example.net>

> hello clp.
>
> i can insert a hex value for a character literal in a string:
>
> >>> stuff = "\x45"
> >>> print stuff
> E
> >>>
>
> can i do something like the above, but using a *binary* number? (e.g.
> 00101101 instead of 45) ?


(Python 3)

 >>> bin(45)
'0b101101'
>>> int(_, 2)
45

-- 
Pablo Mart?
http://www.linkedin.com/in/pmarti || http://www.warp.es
python -c "print '706d6172746940776172702e6573'.decode('hex')"
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/67261312/attachment.html>

From eckhardt at satorlaser.com  Wed Jul 22 06:25:32 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Wed, 22 Jul 2009 12:25:32 +0200
Subject: binary literal
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <s16jj6-c6o.ln1@satorlaser.homedns.org>

superpollo wrote:
> i can insert a hex value for a character literal in a string:
> 
>  >>> stuff = "\x45"
>  >>> print stuff
> E
>  >>>
> 
> can i do something like the above, but using a *binary* number? (e.g.
> 00101101 instead of 45) ?

There are binary number literals since 2.6 and there is the chr() function.

 >>> print chr(0b1000101)
E

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From theajodharan.vfx at gmail.com  Wed Jul 22 06:29:59 2009
From: theajodharan.vfx at gmail.com (TNR)
Date: Wed, 22 Jul 2009 11:29:59 +0100
Subject: Python
In-Reply-To: <6281cf33-8ab6-4ff6-a2c5-a9fa1e66d368@m7g2000prd.googlegroups.com>
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
	<00e687679e63af535bea6a4046f1df08@preisshare.net>
	<mailman.3503.1248229122.8015.python-list@python.org>
	<6281cf33-8ab6-4ff6-a2c5-a9fa1e66d368@m7g2000prd.googlegroups.com>
Message-ID: <dc8c68420907220329h315689d0n8f66c3c82cdac7dd@mail.gmail.com>

Hi,

Check the below links..
http://www.tutorialspoint.com/python/
http://www.java2s.com/Tutorial/Python/CatalogPython.htm

Hope that helps.

Cheers
-theajo



On Wed, Jul 22, 2009 at 5:42 AM, Prateek <prateekkakirwar at gmail.com> wrote:

> Chk dis out ...
>
> http://www.swaroopch.com/notes/Python
>
> It's gr8 guide for beginners
>
> Cheers!!!
> Prateek
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/63bd5dc3/attachment.html>

From sjmachin at lexicon.net  Wed Jul 22 06:34:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 22 Jul 2009 10:34:16 +0000 (UTC)
Subject: Fast reading and unpacking of binary data (struct module)
References: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>
Message-ID: <loom.20090722T100951-701@post.gmane.org>

Daniel Platz <mail.to.daniel.platz <at> googlemail.com> writes:

> 
> Hi,
> 
> I have a Python newbie question about reading data from a binary file.
> I have an huge binary file from an external program.

Please translate "huge" into Mb. Also, how much free real memory do you have?

> I want to read
> and process the data in this file in a reasonable time. It turns out
> that the reading of the data itself and the processing do not need
> most of the time. However, when using the read(bytes) method Python
> returns a string representing the binary information in hex.

"In hex" is not part of the string's nature. If you look at it through
hexadecimal/decimal/octal/binary spectacles, you'll see respectively
hex/decimal/octal/binary.

> This
> string I have to "cast/translate" into a number (in my case a signed
> short). For this I am using the method struct.unpack from the struct
> module. This unpacking part of the program takes by far the most time.
> Is there a way to speed this up or to do it the unpacking more
> cleverly than with the struct module?

Are you reading the file (a) two bytes at a time (b) several Kb at a time (c)
whole file?

Are you unpacking it ... [same options as above but the two answers may differ]?

What are you planning to do with this large list/array? The array option that
Gabriel mentioned should be fastest to load, and take up least memory, but
working with the elements will require making int objects out of the shorts (and
the reverse if you are updating the array).

Is numpy (http://numpy.scipy.org/) a possibility?

Cheers,

John



From drunkard at thepub.co.za  Wed Jul 22 07:05:31 2009
From: drunkard at thepub.co.za (Mark du Preez)
Date: Wed, 22 Jul 2009 13:05:31 +0200
Subject: Documentation Problems
Message-ID: <h46rpv$lm5$1@adenine.netfront.net>

Hi

Can anyone tell me where to go to suggest changes to the Python 
documentation?

Thanks. 




From ndbecker2 at gmail.com  Wed Jul 22 07:12:07 2009
From: ndbecker2 at gmail.com (Neal Becker)
Date: Wed, 22 Jul 2009 07:12:07 -0400
Subject: Fast reading and unpacking of binary data (struct module)
References: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>
Message-ID: <h46s68$pnr$1@ger.gmane.org>

Daniel Platz wrote:

> Hi,
> 
> I have a Python newbie question about reading data from a binary file.
> I have an huge binary file from an external program. I want to read
> and process the data in this file in a reasonable time. It turns out
> that the reading of the data itself and the processing do not need
> most of the time. However, when using the read(bytes) method Python
> returns a string representing the binary information in hex. This
> string I have to "cast/translate" into a number (in my case a signed
> short). For this I am using the method struct.unpack from the struct
> module. This unpacking part of the program takes by far the most time.
> Is there a way to speed this up or to do it the unpacking more
> cleverly than with the struct module?
> 
> Thanks in advance.
> 
> With kind regards,
> 
> Daniel

Consider mmap
Consider numpy
Consider numpy+mmap




From mail at timgolden.me.uk  Wed Jul 22 07:15:22 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 22 Jul 2009 12:15:22 +0100
Subject: Documentation Problems
In-Reply-To: <h46rpv$lm5$1@adenine.netfront.net>
References: <h46rpv$lm5$1@adenine.netfront.net>
Message-ID: <4A66F4CA.2070506@timgolden.me.uk>

Mark du Preez wrote:
> Hi
> 
> Can anyone tell me where to go to suggest changes to the Python 
> documentation?

Drop an entry in the tracker:

  http://bugs.python.org

Patches are always welcome, or at least suggested wording rather
than vague "I don't think it should say that" -- although that's
better than nothing!

TJG


From nipunreddevil at gmail.com  Wed Jul 22 07:15:33 2009
From: nipunreddevil at gmail.com (nipun batra)
Date: Wed, 22 Jul 2009 16:45:33 +0530
Subject: GTK+ ques
Message-ID: <1e61b3260907220415g6edb24sb7fe07c83fe346c8@mail.gmail.com>

I need to develop a GUI preferably in GTK using c or PYGTK.I have little
idea about Python.
Following are requiremnts of the application:
should be GUI
Sould be real time
Should interface serial port
should display moving maps,like google earth
It is basically for Ground control station of a UAV.
How would Python+Pygtk combo work?
is python slower than c/c++ ,if then by how much?
any suggestions for the applcation?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/0f115d13/attachment.html>

From deets at nospam.web.de  Wed Jul 22 07:15:45 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 22 Jul 2009 13:15:45 +0200
Subject: Documentation Problems
References: <h46rpv$lm5$1@adenine.netfront.net>
Message-ID: <7coan1F28i1q2U1@mid.uni-berlin.de>

Mark du Preez wrote:

> Hi
> 
> Can anyone tell me where to go to suggest changes to the Python
> documentation?
> 
> Thanks.

http://docs.python.org/ has a "bugs"-section that leads to

http://docs.python.org/bugs.html

You can file doc-bugs in the tracker, and check if they are already fixed in
the dev-docs.

Diez


From wilk at flibuste.net  Wed Jul 22 07:38:08 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 11:38:08 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
Message-ID: <4a66fa20$0$11368$426a74cc@news.free.fr>

I updated the script (python, c and java) with your unrolled version 
+ somes litle thinks.

I also tried with python3.1, unladen Q2, ironpython1.1.1

Unfortunately it doesn't work more with shedskin, i'll see on the 
shedskin group...

c 1.85s
gcj 2.15s
java 2.8s
python2.5 + psyco 3.1s
unladen-2009Q2 145s (2m45)
python2.5 254s (4m14s)
python3.1 300s (5m)
ironpython1.1.1 680s (11m20)


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From wfluro at gmail.com  Wed Jul 22 07:38:43 2009
From: wfluro at gmail.com (ulf)
Date: Wed, 22 Jul 2009 04:38:43 -0700 (PDT)
Subject: Python ctypes on win64
Message-ID: <f415d834-b2ac-4036-afb1-a12c79480eb4@i6g2000yqj.googlegroups.com>

Hi,

Does anybody know if python includes a win64 version of ctypes?

According to the documentation it should be included - at least
there's no special remarks for win64, and I haven't found any recent
notes saying that it shouldn't work on win64. Yet it looks like both
the installer from Python.org and from ActiveState.com have disabled
it.

regards

/ulfw


From duncan.booth at invalid.invalid  Wed Jul 22 07:55:13 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 22 Jul 2009 11:55:13 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86skgr0yjn.fsf@gmail.com>
	<pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au>
Message-ID: <Xns9C5082EB1B123duncanbooth@127.0.0.1>

Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> wrote:

> But that's the wrong solution to the problem. The OP wants the largest
> (or smallest) item, which he expects to get by sorting, then grabbing
> the first element:
> 
> sorted(alist)[0]
> 
> That requires sorting the entire list, only to throw away everything 
> except the first item. A better solution is to use min() and max(), 
> neither of which sort the list, so they are much faster.
> 
And if they want the n smallest or largest items (where n is significantly 
less than the length of the list[*]) they might consider using 
heapq.nsmallest() and heapq.nlargest()

I find it interesting that the heapq functions tell you in the 
documentation that they aren't suitable for use where n==1 or where n is 
near the total size of the sequence whereas random.sample() chooses what it 
thinks is the best algorithm based on the input. At the very least I would 
have thought the heapq functions could check for n==1 and call min/max when 
it is.

[*] Some quick playing with timeit seems to indicate that with a list of 
200 integers nsmallest is fastest (by a very small margin) when n==2 and 
n==3 but is beaten by sorted[:n] when n==4, so I guess you need a 
reasonably long list to make it worth not sorting it: with list of 20,000 
integers it isn't worth sorting unless you want more than about 700 items.

-- 
Duncan Booth http://kupuguy.blogspot.com


From deets at nospam.web.de  Wed Jul 22 07:55:29 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 22 Jul 2009 13:55:29 +0200
Subject: List insertion cost
References: <mailman.3481.1248204184.8015.python-list@python.org>
Message-ID: <7cod1hF28nhhlU1@mid.uni-berlin.de>

Lucas P Melo wrote:

> Hello,
> I would like to know how much it costs to insert an element into a list
> using this operation:
> a[2:2] = [ 1 ]
> i. e, what is the complexity of the operation above (given that len(a) =
> n)?

O(n) I'd say. You need to copy nearly the whole list, and sometimes
re-allocate it's storage (they are internally stored as arrays of object
references)

Diez


From jeanmichel at sequans.com  Wed Jul 22 08:16:19 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 22 Jul 2009 14:16:19 +0200
Subject: doted filenames in import statements
In-Reply-To: <m2prbtllen.fsf@cs.uu.nl>
References: <mailman.3488.1248212574.8015.python-list@python.org>
	<m2prbtllen.fsf@cs.uu.nl>
Message-ID: <4A670313.8040204@sequans.com>

Piet van Oostrum wrote:
>
> [snip]
>
>> JP> file = "/home/dsp/4.6.0.0/test.py"
>> JP> test = __import__(file)
>> JP> => no module name blalalal found.
>>     
>
>   
>> JP> Any suggestion ? I tried multiple escape technics without any success.
>>     
>
> Rightly so.
>
> I think the best would be to add the directory to sys.path 
> sys.path.add('/home/dsp/4.6.0.0')
> and then
> __import__('test', ... ) 
>   

I see. My problem is that a have to import 2 different files having de 
same name. In the same name space I have 2 objects from 2 different 
software branches, let's say 4.6.0 and 4.6.1.
The first object shall import 4.6.0/orb.py and the second one 4.6.1/orb.py.

If I add 4.6.1 to sys.path, the import statement will look like:
self._orb = __import__('orb')
The problem is, python wil assume orb is already imported and will 
assign the module from the 4.6.0 branch to my 4.6.1 object.

Do I have to mess up with sys.modules keys to make python import the 
correct file ? Is there a standard/proper way to do that ?

JM


From ryniek90 at gmail.com  Wed Jul 22 08:29:20 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 22 Jul 2009 14:29:20 +0200
Subject: Changing the private variables content
In-Reply-To: <mailman.13231.1248210896.8014.python-list@python.org>
References: <mailman.13231.1248210896.8014.python-list@python.org>
Message-ID: <4A670620.1090501@gmail.com>

>
> ------------------------------------------------------------------------
>
> Temat:
> Re: Changing the private variables content
> Od:
> Gary Herron <gherron at islandtraining.com>
> Data:
> Tue, 21 Jul 2009 14:14:44 -0700
> Do:
> Ryniek90 <ryniek90 at gmail.com>
>
> Do:
> Ryniek90 <ryniek90 at gmail.com>
> Kopia:
> python-list at python.org
>
>
> Ryniek90 wrote:
>> Hi.
>> I'm writing some class, and decided to use inside private method and 
>> some private variables. While with method i haven't got any problem's 
>> with variables i have.
>> Maybe some example.
>> A class with private method and private variable:
>>
>> "
>> >>> class Secret(object):
>>    #
>>    def __init__(self):
>>        self._number = 1
>>    #
>>    def _secret(self):
>>        print self._number
>>    def showit(self):
>>        print "Secret number is:\n"
>>        self._secret()
>>
>> >>> sec = Secret()
>> >>> sec.showit()
>> Secret number is:
>>
>> 1
>> >>> sec._number
>> 1
>> >>> sec._number = 2
>> >>> sec._number
>> 2
>> >>> sec._number += 3
>> >>> sec._number
>> 5
>> >>>
>> "
>>
>> As You can see, i made class with private method and private variable 
>> inside __init__ constructor. I've changed also the variable value, 
>> but outside class.
>> I've got problem with changing some variable value _inside__my_ 
>> class, which i'm writing.
>
> Not sure this is what you are asking, but a method (which is how I 
> interpret "_inside__my_ class") changes the value by normal assignment 
> like this:
>
> class Secret(object):
>  ...
>  def SetNumber(self,value):
>    self._number = value
>
> Is that what you were asking?
>
>
> Gary Herron
>
>
>
>> I've searched over google, some tuts with topics about operations on 
>> private variables, but didn't found anything - only how to make them, 
>> but no how to assign new objects/override them with new content (and 
>> other advanced and helpful options).
>>
>> If someone could help me, it would be great.
>>
>> Thanks.
>
>


Thanks for hint, but looks like i can't do what i want.

Maybe i show You my class:

"

class ModPrint(object):
   
    u"""
    This will be the doc.
    """
   
    def __init__(self):
       
        #Assign the Python installation directory - sys.exec_prefix - to 
variable
        self._default_search_path=sys.exec_prefix
        self._chosen_module = ''
        self._user_search_path = ''
        self._this_module = ''
       
    def _SetVar(self, attr, val):
        self.attr = val   
       
    def _search_for_module(self, *args):
       
        """Private method which walks through default Python 
installation directories, and search for prefered module."""
       
        #walking thru all directories available in path '_user_search_path'
        for root, dirs, files in os.walk(self._user_search_path):
            for f in files:
               
                #if found file 'f' is THAT module,
                #full path to THAT file is assigned to variable
                if f == ("%s.py" % self._chosen_module):
                    self._SetVar(self._this_module, os.path.join(root, f))
                   
                   
    def print_module(self, _chosen_module='', _user_search_path='', 
_default_search_path=sys.exec_prefix,):
       
        """Reads module chosen by user, and returns full content of this 
module, as it is."""
       
       
        #if custom search path hasn't been assigned,
        #default path is being assigned as custom path
        if self._user_search_path == '':
            self._user_search_path = self._default_search_path
           
        #using private method '_search_for_module' with 'self.' preffix
        #to search for prefered module
        self._search_for_module(_chosen_module, _user_search_path)
       
        #opening prefered module with read-only binary mode
        #and assigning it to 'module_open' variable
        module_open = open(self._this_module, 'rb')
       
        #reading this file and assigning it to variable
        module_text = module_open.read()
       
        #closing read file; the read content is still available
        #it's stored in variable 'module_text'
        module_open.close()
       
        #returning the read content
        return module_text

"

When i use this class in Python IDLE, i've got this error:
"
 >>> mod = ModPrint()
 >>> import socket
 >>> mod.print_module('socket')

Traceback (most recent call last):
  File "<pyshell#60>", line 1, in <module>
    mod.print_module('socket')
  File "<pyshell#57>", line 48, in print_module
    module_open = open(self._this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

As You can see, i can't assign the new value "os.path.join(root, f)" to 
the 'self._this_module variable'.
So for sure i've made some mistake in method:

"
def _SetVar(self, attr, val):
        self.attr = val   
"
When i've changed private variables to normal, stored in class (in 
__init__ method), it was the same situation - i couldn't change this 
variable value.

"
 >>> mod = ModPrint()
 >>> mod.print_module('os')

Traceback (most recent call last):
  File "<pyshell#72>", line 1, in <module>
    mod.print_module('os')
  File "<pyshell#64>", line 48, in print_module
    module_open = open(self.this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

Thanks i someone could help me, give some hint.


From contact at xavierho.com  Wed Jul 22 08:45:37 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 22:45:37 +1000
Subject: Changing the private variables content
In-Reply-To: <4A670620.1090501@gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
Message-ID: <2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>

On Wed, Jul 22, 2009 at 10:29 PM, Ryniek90 <ryniek90 at gmail.com> wrote:

> Thanks for hint, but looks like i can't do what i want.


That's because

>
>         def _SetVar(self, attr, val):
>       self.attr = val


 doesn't work as you might think. However, I tried to replace it with:

val('self.' + attr + '=\'' + val + '\'')

and it gives me a syntax error!

  File "test.py", line 7, in _setVar
    eval('self.' + attr + '=\'' + val + '\'')
  File "<string>", line 1
    self.var='Mrra'
            ^
SyntaxError: invalid syntax

So, uh, I'm wondering if this is a bug. And also the solution to his
problem.

Good luck. Any ideas appreciated.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/44ef6fd3/attachment.html>

From python-url at phaseit.net  Wed Jul 22 08:48:25 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Wed, 22 Jul 2009 12:48:25 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul 22)
Message-ID: <h471qp$dfq$1@lairds.us>

QOTW:  "If programming is symbol manipulation, then you should remember that
the user interface is also symbol manipulation, and it is a MUCH harder
problem than databases, sorting, searching, and all the other problems you
learn about in academia. The user interface has to communicate over a rich
but noisy channel using multiple under-specified protocols to a couple of
pounds of meat which processes information using buggy heuristics evolved
over millions of years to find the ripe fruit, avoid being eaten, and have
sex. If you think getting XML was hard, that's *nothing* compared to user
interfaces.

The fact that even bad UIs work at all is a credit to the heuristics, bugs
and all, in the meat." - Steven D'Aprano
     http://groups.google.com/group/comp.lang.python/msg/8c65eacbd76e79cf


    Invoke the same method over every object in a collection:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8fd293a9b39c8733/
    
    There is no 'xor' boolean operator, why? What should be its outcome?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/16eec722310e75e8/
    
    A thread-safe method to create unique identifiers (not necesarily
    increasing integers):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/dfe22a6446c057df/
    
    Tim Chase tells us three ways to turn standard output into unbuffered mode:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/a65f71444bd4bb53/
    
    How to receive data of unknown length using sockets:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/9e4a9f8b6e83320/
    
    Override a method, but keeping the inherited docstring:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/1e4075ba10dcbdd9/
    
    Limiting the execution time of a code fragment:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/734054de170e2904/
    
    Sharing a big object between processes using the multiprocessing module:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/833d4988b7af6353/
    
    Why aren't OrderedDicts [3.1] comparable using <, >, <=, >=?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/c3c6f4fe7b6d487d/
    
    So many ways to call a function - why is that? Beginners get confused:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3fd57f5ee4850530/
    
    The reasons to choose your favorite programming language (Python, I
    presume!):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/5d87008e328efcf9/
    
    Tuples, lists, their differences and motivation:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/cb0cf56c52321ccc/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From contact at xavierho.com  Wed Jul 22 08:52:45 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 22:52:45 +1000
Subject: Changing the private variables content
In-Reply-To: <2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
	<2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>
Message-ID: <2d56febf0907220552q6a96107ds7b60ba46ac82ef6a@mail.gmail.com>

>
> val('self.' + attr + '=\'' + val + '\'')
>

Obviously that was eval, not val. Also it doesn't work without the escaped
single quotes, either.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/5a4fa4b4/attachment.html>

From mark.dufour at gmail.com  Wed Jul 22 08:55:57 2009
From: mark.dufour at gmail.com (srepmub)
Date: Wed, 22 Jul 2009 05:55:57 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
Message-ID: <d6f06288-4250-4065-bdf1-a880de3b875a@y7g2000yqa.googlegroups.com>


please send any program that doesn't work with shedskin (it still is
experimental after all) to me, or create an issue at
shedskin.googlecode.com, and I will have a look at the problem.


thanks,
mark.


From wilk at flibuste.net  Wed Jul 22 08:59:37 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 12:59:37 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
	<d6f06288-4250-4065-bdf1-a880de3b875a@y7g2000yqa.googlegroups.com>
Message-ID: <4a670d39$0$11286$426a74cc@news.free.fr>

On 22-07-2009, srepmub wrote:
>
> please send any program that doesn't work with shedskin (it still is
> experimental after all) to me, or create an issue at
> shedskin.googlecode.com, and I will have a look at the problem.

I did it, on the discussion group
http://groups.google.com/group/shedskin-discuss/browse_thread/thread/c1f47a7c21897b44

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From disappearedng at gmail.com  Wed Jul 22 09:04:18 2009
From: disappearedng at gmail.com (disappearedng)
Date: Wed, 22 Jul 2009 21:04:18 +0800
Subject: Finding all cycles within an undirected graph
Message-ID: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>

Hey everyone,
I am interested to find out all the cycles within an undirected graph.
I don't have a particular implementation of nodes and vertices yet, so
would someone kindly point out a good graph library for this ( I
looked at pygraph and python-graph, but not really satisfied ), in
addition to good algorithm for solving this issue.


From contact at xavierho.com  Wed Jul 22 09:06:22 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 23:06:22 +1000
Subject: Changing the private variables content
In-Reply-To: <2d56febf0907220552q6a96107ds7b60ba46ac82ef6a@mail.gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
	<2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>
	<2d56febf0907220552q6a96107ds7b60ba46ac82ef6a@mail.gmail.com>
Message-ID: <2d56febf0907220606q19e343f2mdd276d4e734ee048@mail.gmail.com>

Got it:

exec('self.' + attr + '=\'' + val + '\'')

That worked. I think it'll do what you want now ;)

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/12f34301/attachment.html>

From davea at ieee.org  Wed Jul 22 09:11:26 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 09:11:26 -0400
Subject: Multiple versions of python
In-Reply-To: <98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>	<mailman.3465.1248186000.8015.python-list@python.org>
	<98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
Message-ID: <4A670FFE.80405@ieee.org>

CCW wrote:
> On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
>   
>> ChrisW wrote:
>>     
>>> Hi,
>>>       
>>> I have installed 2 versions of python on my Windows XP computer - I
>>> originally had 3.0.1, but then found that the MySQL module only
>>> supported 2.*, so I've now installed that.  I have found that if I
>>> change the Windows Environment Variable path, then I can change the
>>> version of python called when I type 'python' into a command line.
>>> However, I'd like to be able to choose which version I use.  I know
>>> that if I change C:\Python26\python.exe to
>>> C:\Python26\python2.exe and C:\Python30\python.exe to C:
>>> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
>>> the correct interpreter.  However, is it safe just to rename the
>>> executable files? Is there a more elegant way to achieve the same
>>> task?
>>>       
>>> Thanks,
>>> Chris
>>>       
>> The elegant way is to have a batch directory on your PATH ( I use  
>> m:\t\bat )  and put your *.bat files there.   I do NOT put any python
>> installations on the PATH.
>>
>> For example, I have a batch file called:     m:\t\bat\python26.bat
>>
>> c:\progfiles\python26\python.exe %*
>>
>> The %* syntax means pass all arguments through to the program.
>>
>> Once it all works, you can add an "@" in front of the c:   in order to
>> suppress echoing the command.  At that point, it'll look and work the
>> same way as what you did, but without modifying anything in the install
>> directory.    (You may want  python26.bat, pythonw26.bat, python31.bat
>> and pythonw31.bat)
>>
>> The other thing you may want to do in a batch file is to change the file
>> associations so that you can run the .py file directly, without typing
>> "python" or "pythonw" in front of it.
>>
>> The relevant Windows commands are:     assoc and ftype      And on a
>> related note, you may want to edit the PATHEXT environment variable, to
>> add .PY and .PYW
>>     
>
> Thanks for this - this way made a bit more sense to me.  I've now got
> C:\commands with the 4 .bat files in, and C:\commands in my path.  It
> all seems to work :) I think I've missed the point of the @ though -
> it doesn't seem to make any difference..
>
> I'm also a bit confused with the associations - since I've got python
> 2.6 and 3.1, surely the command I type (python26 or python31) is the
> only way to force a script to be run using a specific interpreter at
> runtime without having to change the .bat file every time I want to
> run a script using 3.1 instead of 2.6?
>
>   
The @ symbol was used in older versions of CMD and COMMAND to suppress 
echoing of the command line.  I think if you're using XP or later, it 
doesn't matter.

As for file associations, I don't know just what you already know 
about.  When you type    data.doc    at a command line, the system looks 
for the data file, then if it's found, it looks up the program 
associated with that extension.  On my machine, that's a particular 
version of Word for Windows.  Similarly, if I type    digest.py   and 
I'm in the directory containing that file, the system looks up my 
associations, and runs Python 2.6 on that file.  If I wanted it to run 
Python 3.1 on that file, I'd have to change the associations, temporarily.

So, first approximation, it's a way to avoid having to type PYTHON each 
time I want to run a script, as long as I don't need any other arguments 
on the (implied) command line.  Further, the system will then look for 
digest.py everywhere on the PATH, so I don't even have to be in the same 
directory.  And that means I can be in the data directory that digest.py 
is going to work on.  Effectively, it raises digest.py to feeling like 
an executable, for most purposes.  In fact, I put all my scripts in a 
directory, along with other simple executables.   I use  m:\t\bin  for 
that purpose.

These associations (to .py and .pyw) are established by the installer 
program for Python.  But when you had multiple installs, you could 
choose whether the second one installed overrides the first.  My point 
is that if you need to change them back and forth, you could use  assoc 
and ftype to do it.

On my system:

M:\LabOrders>assoc .py
.py=Python.File

M:\LabOrders>ftype Python.File
Python.File="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*

M:\LabOrders>


So my .py files are associated with the 2.6.2 version of ActivePython 
installation.   Note the similarity of the ftype to your python26.bat file?

One more little trick is that I could just type   digest    instead 
of    digest.py,   if I have added the .py and .pyw extensions to my   
PATHEXT environment variable.    So my PATHEXT looks like:
   PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.PY;.PYW



Note that the association changes made by  assoc and ftype are global.  
They apply to all cmd.exe windows, even those already running, and they 
survive a reboot.  But when you set environment variables like PATHEXT,  
you can choose to do it in a single window (with SET), or globally 
(using control-panel).

If I found myself switching often, I'd make separate ftype entries for 
each interpreter, something like
  Python.File26="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*
  Python.File31="C:\PROGFI~1\.....      

and just change assoc .py  to point at the one I needed today.

As it is, I'm content leaving the associations pointing at 2.6, and 
explicitly entering PYTHON31 in front of any script name I want to run 
on that interpreter.

DaveA



From python at mrabarnett.plus.com  Wed Jul 22 09:12:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 22 Jul 2009 14:12:18 +0100
Subject: Changing the private variables content
In-Reply-To: <4A670620.1090501@gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
Message-ID: <4A671032.10304@mrabarnett.plus.com>

Ryniek90 wrote:
>>
>> ------------------------------------------------------------------------
>>
>> Temat:
>> Re: Changing the private variables content
>> Od:
>> Gary Herron <gherron at islandtraining.com>
>> Data:
>> Tue, 21 Jul 2009 14:14:44 -0700
>> Do:
>> Ryniek90 <ryniek90 at gmail.com>
>>
>> Do:
>> Ryniek90 <ryniek90 at gmail.com>
>> Kopia:
>> python-list at python.org
>>
>>
>> Ryniek90 wrote:
>>> Hi.
>>> I'm writing some class, and decided to use inside private method and 
>>> some private variables. While with method i haven't got any problem's 
>>> with variables i have.
>>> Maybe some example.
>>> A class with private method and private variable:
>>>
>>> "
>>> >>> class Secret(object):
>>>    #
>>>    def __init__(self):
>>>        self._number = 1
>>>    #
>>>    def _secret(self):
>>>        print self._number
>>>    def showit(self):
>>>        print "Secret number is:\n"
>>>        self._secret()
>>>
>>> >>> sec = Secret()
>>> >>> sec.showit()
>>> Secret number is:
>>>
>>> 1
>>> >>> sec._number
>>> 1
>>> >>> sec._number = 2
>>> >>> sec._number
>>> 2
>>> >>> sec._number += 3
>>> >>> sec._number
>>> 5
>>> >>>
>>> "
>>>
>>> As You can see, i made class with private method and private variable 
>>> inside __init__ constructor. I've changed also the variable value, 
>>> but outside class.
>>> I've got problem with changing some variable value _inside__my_ 
>>> class, which i'm writing.
>>
>> Not sure this is what you are asking, but a method (which is how I 
>> interpret "_inside__my_ class") changes the value by normal assignment 
>> like this:
>>
>> class Secret(object):
>>  ...
>>  def SetNumber(self,value):
>>    self._number = value
>>
>> Is that what you were asking?
>>
>>
>> Gary Herron
>>
>>
>>
>>> I've searched over google, some tuts with topics about operations on 
>>> private variables, but didn't found anything - only how to make them, 
>>> but no how to assign new objects/override them with new content (and 
>>> other advanced and helpful options).
>>>
>>> If someone could help me, it would be great.
>>>
>>> Thanks.
>>
>>
> 
> 
> Thanks for hint, but looks like i can't do what i want.
> 
> Maybe i show You my class:
> 
> "
> 
> class ModPrint(object):
>      u"""
>    This will be the doc.
>    """
>      def __init__(self):
>              #Assign the Python installation directory - sys.exec_prefix 
> - to variable
>        self._default_search_path=sys.exec_prefix
>        self._chosen_module = ''
>        self._user_search_path = ''
>        self._this_module = ''
>          def _SetVar(self, attr, val):
>        self.attr = val            def _search_for_module(self, *args):
>              """Private method which walks through default Python 
> installation directories, and search for prefered module."""
>              #walking thru all directories available in path 
> '_user_search_path'
>        for root, dirs, files in os.walk(self._user_search_path):
>            for f in files:
>                              #if found file 'f' is THAT module,
>                #full path to THAT file is assigned to variable
>                if f == ("%s.py" % self._chosen_module):
>                    self._SetVar(self._this_module, os.path.join(root, f))
>                                        def print_module(self, 
> _chosen_module='', _user_search_path='', 
> _default_search_path=sys.exec_prefix,):
>              """Reads module chosen by user, and returns full content of 
> this module, as it is."""
>                    #if custom search path hasn't been assigned,
>        #default path is being assigned as custom path
>        if self._user_search_path == '':
>            self._user_search_path = self._default_search_path
>                  #using private method '_search_for_module' with 'self.' 
> preffix
>        #to search for prefered module
>        self._search_for_module(_chosen_module, _user_search_path)
>              #opening prefered module with read-only binary mode
>        #and assigning it to 'module_open' variable
>        module_open = open(self._this_module, 'rb')
>              #reading this file and assigning it to variable
>        module_text = module_open.read()
>              #closing read file; the read content is still available
>        #it's stored in variable 'module_text'
>        module_open.close()
>              #returning the read content
>        return module_text
> 
> "
> 
> When i use this class in Python IDLE, i've got this error:
> "
>  >>> mod = ModPrint()
>  >>> import socket
>  >>> mod.print_module('socket')
> 
> Traceback (most recent call last):
>  File "<pyshell#60>", line 1, in <module>
>    mod.print_module('socket')
>  File "<pyshell#57>", line 48, in print_module
>    module_open = open(self._this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> As You can see, i can't assign the new value "os.path.join(root, f)" to 
> the 'self._this_module variable'.
> So for sure i've made some mistake in method:
> 
> "
> def _SetVar(self, attr, val):
>        self.attr = val   "
> When i've changed private variables to normal, stored in class (in 
> __init__ method), it was the same situation - i couldn't change this 
> variable value.
> 
> "
>  >>> mod = ModPrint()
>  >>> mod.print_module('os')
> 
> Traceback (most recent call last):
>  File "<pyshell#72>", line 1, in <module>
>    mod.print_module('os')
>  File "<pyshell#64>", line 48, in print_module
>    module_open = open(self.this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> Thanks i someone could help me, give some hint.

What is the point of the _SetVar method?

Instead of:

     self._SetVar(self._this_module, os.path.join(root, f))

just do:

     self._this_module = os.path.join(root, f)

(unless I'm misunderstanding what you're trying to do!)


From alan.isaac at gmail.com  Wed Jul 22 09:14:12 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Wed, 22 Jul 2009 13:14:12 GMT
Subject: invoke method on many instances
In-Reply-To: <mailman.3417.1248074972.8015.python-list@python.org>
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>	<02701d35$0$5185$c3e8da3@news.astraweb.com>	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
Message-ID: <EgE9m.507$646.499@nwrddc01.gnilink.net>

>>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>>> def apply2(itr, methodname, *args, **kwargs):
>>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>>     for item in itr:
>>>>         f(item)


>> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>>> for obj in objects:
>>>     getattr(obj, methodname)(*args, **kwargs)


> En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac:
>> Are there any obvious considerations in choosing 
>> between those two? 


On 7/20/2009 3:29 AM Gabriel Genellina apparently wrote:
> The operator.methodcaller version is faster in my tests for large 
> collections, but slightly slower when you have very few elements. 


So it seems.  Is this easily explained?

Thanks,
Alan Isaac


From breamoreboy at yahoo.co.uk  Wed Jul 22 09:18:55 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Wed, 22 Jul 2009 14:18:55 +0100
Subject: Python
In-Reply-To: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
Message-ID: <h473jt$g3l$1@ger.gmane.org>

khanh le wrote:
> do you have any materials about Python?
> can you show me the link of Python or some books?
> thanks a lots!
> 
> -- 
> Regard!
> Khanh
> 
This comes highly recommeended http://diveintopython.org/

Regards.



From Caseyweb at gmail.com  Wed Jul 22 09:23:33 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Wed, 22 Jul 2009 06:23:33 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
Message-ID: <9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com>

On Jul 22, 5:27?am, Phillip B Oldham <phillip.old... at gmail.com> wrote:
> I understand that there are a number of MapReduce frameworks/tools
> that play nicely with Python (Disco, Dumbo/Hadoop), however these have
> "large" dependencies (Erlang/Java). Are there any MapReduce frameworks/
> tools which are either pure-Python, or play nicely with Python but
> don't require the Java/Erlang runtime environments?

I can't answer your question, but I would like to better understand
the
problem you are trying to solve.  The Apache Hadoop/MapReduce java
application isn't really that "large" by modern standards, although it
is generally run with large heap sizes for performance (-Xmx1024m or
larger for the mapred.child.java.opts parameter).

MapReduce is designed to do extremely fast parallel data set
processing
on terabytes of data over hundreds of physical nodes; what advantage
would a pure Python approach have here?


From contact at xavierho.com  Wed Jul 22 09:24:05 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 23:24:05 +1000
Subject: Changing the private variables content
In-Reply-To: <4A671032.10304@mrabarnett.plus.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com> <4A671032.10304@mrabarnett.plus.com>
Message-ID: <2d56febf0907220624u7401550ei24461dd9ca7d6934@mail.gmail.com>

> What is the point of the _SetVar method?
>
>
So you can set any variable in that class, I guess?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/d1a3ee8c/attachment.html>

From brendon.wickham at gmail.com  Wed Jul 22 09:28:16 2009
From: brendon.wickham at gmail.com (Brendon Wickham)
Date: Wed, 22 Jul 2009 23:28:16 +1000
Subject: Getting cookie "expires" value
Message-ID: <c07e3c70907220628t5b32e0f5s7ca3e422884e592b@mail.gmail.com>

Hi there,

My web application uses a cookie to set/get a session id. This is
working fine. However, I'm unable to work out how to get the cookie
"expires" value.

Below is test code that replicates the problem. It creates a simple
web page and shows a cookie value if it's found, or creates a new one
(correctly setting the "expires" value) and indicates that it was
created:

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
#!/usr/bin/env python
import Cookie,os

def printHeader():
??? print "Content-type: text/html\n"
??? print "<html><title>Cookie test</title>"
??? print "<body>"

cookies=Cookie.SimpleCookie(os.environ.get('HTTP_COOKIE'))

if cookies.has_key('test'):
??? #If cookie was found:
??? printHeader()
??? print "Found cookie:<br/><br/>"

??? #Get cookie:
??? c = cookies.get('test')

??? #Print its value:
??? print "<div>Value: %s</div>" % c.value

??? #Iterate through its items and print name/value:
??? for k,v in c.items():
??? ??? ?print "<div>%s=%s</div>" % (k,v)

else:
??? #Define cookie:
??? cookies['test'] = "1234"
??? cookies['test']['expires'] = 3600

??? #Save cookie:
??? print cookies['test']

??? #Now print HTML:
??? printHeader()

??? print "Cookie created."

print "</body></html>"
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<


This is what I get if the cookie exists:
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Found cookie:

Value: 1234
comment=
domain=
secure=
expires=
max-age=
version=
path=
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

As you can see, the cookie attributes are valueless. Can anyone help?
Am I missing something fundamental?

Cheers,

Brendon


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul 22 09:28:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 22 Jul 2009 13:28:23 GMT
Subject: Changing the private variables content
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<mailman.3521.1248265771.8015.python-list@python.org>
Message-ID: <02770500$0$5185$c3e8da3@news.astraweb.com>

On Wed, 22 Jul 2009 14:29:20 +0200, Ryniek90 wrote:

> When i use this class in Python IDLE, i've got this error: "
...
> Traceback (most recent call last):
>   File "<pyshell#60>", line 1, in <module>
>     mod.print_module('socket')
>   File "<pyshell#57>", line 48, in print_module
>     module_open = open(self._this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> As You can see, i can't assign the new value "os.path.join(root, f)" to
> the 'self._this_module variable'.

In the __init__ method, you successfully set the `_this_module` attribute:

        self._this_module = ''

That works, so it proves that you *can* set a private attribute.

Later on, you call the `_SetVar` method, which does this:

    def _SetVar(self, attr, val):
        self.attr = val   

In English, this method does this:

(1) Take two arguments, and store them in variables called "attr" and 
"val".

(2) Assign the value stored in "val" to an attribute named exactly "attr".

What you actually want is:

(1) Take two arguments, and store them in variables called "attr" and 
"val".

(2) Assign the value stored in "val" to an attribute with the name stored 
in the variable "attr".

Can you see the difference?

What you actually want is:

    def _SetVar(self, attr, val):
        setattr(self, attr, val)


Your code is terribly complicated. This will probably do what you want. 
(Warning -- I haven't tested it, so there may be a few errors.)


class ModPrint(object):
    u"""
    This will be the doc.
    """
    def __init__(self, default_search_path=''):
        self.default_search_path = ''

   def find_module(self, modulename, search_path=''):
       if search_path == '':
           # Try the default search path instead.
           search_path = self.default_search_path
        if search_path == '':  # still blank.
            # Try the Python search path instead.
           search_path = sys.exec_prefix
        for root, dirs, files in os.walk(search_path):
            for f in files:
                if f == "%s.py" % modulename:
                    return os.path.join(root, f)

    def get_module_text(self, modulename, search_path=''):
        filename = self.find_module(modulename, search_path)
        module_open = open(filename, 'rb')
        module_text = module_open.read()
        module_open.close()
        return module_text


I changed the name of print_module_text because it doesn't actually print 
anything.



-- 
Steven


From robin at reportlab.com  Wed Jul 22 09:37:35 2009
From: robin at reportlab.com (Robin Becker)
Date: Wed, 22 Jul 2009 14:37:35 +0100
Subject: Finding all cycles within an undirected graph
In-Reply-To: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
References: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
Message-ID: <4A67161F.8090908@chamonix.reportlab.co.uk>

disappearedng wrote:
> Hey everyone,
> I am interested to find out all the cycles within an undirected graph.
> I don't have a particular implementation of nodes and vertices yet, so
> would someone kindly point out a good graph library for this ( I
> looked at pygraph and python-graph, but not really satisfied ), in
> addition to good algorithm for solving this issue.

this one has been updated recently

http://code.google.com/p/python-graph/

also this page has many links http://wiki.python.org/moin/PythonGraphApi
-- 
Robin Becker



From jjkk73 at gmail.com  Wed Jul 22 09:39:09 2009
From: jjkk73 at gmail.com (jorma kala)
Date: Wed, 22 Jul 2009 15:39:09 +0200
Subject: How to document Python code properly for Pydoc
Message-ID: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>

Hi,
Do you know where I can find the rules for documenting Python code, so that
automatic document generation with Pydoc makes the most of the comments
inserted in the code?
I know about documenting class and method through triple quote just under
the class definition. But how do you comment a specific field or variable,
or how do you document function arguments so that they are extracted like in
javadoc?
Thanks very much
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/827104d7/attachment.html>

From rhodri at wildebst.demon.co.uk  Wed Jul 22 10:01:09 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 22 Jul 2009 15:01:09 +0100
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <op.uxg2j7b5a8ncjz@gnudebst>

On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina  
<gagsl-py2 at yahoo.com.ar> wrote:


> class X(object):
>    foo = descriptor()
>
> x = X()
> x.foo = "value"

Isn't this going to create a brand new instance attribute x.foo that has  
nothing to do with the descriptor anyway?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From ryniek90 at gmail.com  Wed Jul 22 10:01:19 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 22 Jul 2009 16:01:19 +0200
Subject: Changing the private variables content
In-Reply-To: <mailman.13388.1248268320.8014.python-list@python.org>
References: <mailman.13388.1248268320.8014.python-list@python.org>
Message-ID: <4A671BAF.1060204@gmail.com>

>
> Got it:
>
> exec('self.' + attr + '=\'' + val + '\'')
>
> That worked. I think it'll do what you want now ;)
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com <mailto:contact at xavierho.com>
> Website: http://xavierho.com/

To bad, that didn't worked in my class. Still the same error:
"
 >>> mod.print_module('socket')

Traceback (most recent call last):
  File "<pyshell#121>", line 1, in <module>
    mod.print_module('socket')
  File "<pyshell#118>", line 51, in print_module
    module_open = open(self._this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

:-/
> What is the point of the _SetVar method?
>
> Instead of:
>
>     self._SetVar(self._this_module, os.path.join(root, f))
>
> just do:
>
>     self._this_module = os.path.join(root, f)
>
> (unless I'm misunderstanding what you're trying to do!)
>

Of course i;ve tried, but still get the same error:

"
 >>> mod.print_module('socket')

Traceback (most recent call last):
  File "<pyshell#121>", line 1, in <module>
    mod.print_module('socket')
  File "<pyshell#118>", line 51, in print_module
    module_open = open(self.this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

It looks like private variable have specific naure, that prevent from 
traditional editing them.
Still searching for some tuts about private methods and variables.


From Scott.Daniels at Acm.Org  Wed Jul 22 10:06:45 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 22 Jul 2009 07:06:45 -0700
Subject: Multiple versions of python
In-Reply-To: <98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
	<mailman.3465.1248186000.8015.python-list@python.org>
	<98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
Message-ID: <PvqdnX-b4rW-hvrXnZ2dnUVZ_vydnZ2d@pdx.net>

CCW wrote:
> On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
>> The other thing you may want to do in a batch file is to change the file
>> associations so that you can run the .py file directly, without typing
>> "python" or "pythonw" in front of it.
>>
>> The relevant Windows commands are:     assoc and ftype      And on a
>> related note, you may want to edit the PATHEXT environment variable, to
>> add .PY and .PYW
> 
> Thanks for this - this way made a bit more sense to me.  I've now got
> C:\commands with the 4 .bat files in, and C:\commands in my path.  It
> all seems to work :) I think I've missed the point of the @ though -
> it doesn't seem to make any difference..
> 
> I'm also a bit confused with the associations - since I've got python
> 2.6 and 3.1, surely the command I type (python26 or python31) is the
> only way to force a script to be run using a specific interpreter at
> runtime without having to change the .bat file every time I want to
> run a script using 3.1 instead of 2.6?

OK, for me currently:

C:\> assoc .py
.py=Python.File

C:\> assoc .pyw
.pyw=Python.NoConFile

C:\> ftype Python.File
Python.File="C:\Python31\python.exe" "%1" %*

C:\> ftype Python.NoConFile
Python.NoConFile="C:\Python31\pythonw.exe" "%1" %*

C:\> ftype Python.File
Python.File="C:\Python31\python.exe" "%1" %*

Now imagine instead that you've added:

C:\> ftype Python31.File="C:\Python31\python.exe" "%1" %*
C:\> ftype Python31.NoConFile="C:\Python31\pythonw.exe" "%1" %*
C:\> ftype Python26.File="C:\Python26\python.exe" "%1" %*
C:\> ftype Python26.NoConFile="C:\Python26\pythonw.exe" "%1" %*

Then you can do the following:
C:\> assoc .py=Python26.File
C:\> fumble.py
C:\> assoc .py=Python31.File
C:\> fumble.py

That is the basic idea, but at the moment, I don't see a simple demo
working for me.  SO, if you want to pursue this, you can probably get it
to work.

--Scott David Daniels
Scott.Daniels at Acm.Org


From Scott.Daniels at Acm.Org  Wed Jul 22 10:12:18 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 22 Jul 2009 07:12:18 -0700
Subject: Issue combining gzip and subprocess
In-Reply-To: <m2eisam153.fsf@cs.uu.nl>
References: <mailman.3472.1248192725.8015.python-list@python.org>
	<m2eisam153.fsf@cs.uu.nl>
Message-ID: <2YednUGQxvntgfrXnZ2dnUVZ_hWdnZ2d@pdx.net>

Piet van Oostrum wrote:
> ...
> f = gzip.open(filename, 'w')
> proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
> while True:
>     line = proc.stdout.readline()
>     if not line: break
>     f.write(line)
> f.close()

Or even:
     proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
     with gzip.open(filename, 'w') as dest:
         for line in iter(proc.stdout, ''):
             f.write(line)

--Scott David Daniels
Scott.Daniels at Acm.Org


From invalid at invalid  Wed Jul 22 10:13:28 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 22 Jul 2009 09:13:28 -0500
Subject: plotting graph from another file
References: <mailman.3510.1248244109.8015.python-list@python.org>
Message-ID: <096dnaQneZwVg_rXnZ2dnUVZ_hZi4p2d@posted.visi>

On 2009-07-22, jhinak sen <jhinak.sen at gmail.com> wrote:

> i want to plot a distribution graph for following data:

[...]

> can it be done using matplotlib ?
>
> if yes , please give me the code for plotting the importing
> the text file and plotting the graph.

As soon as you're done cleaning my house, washing my car, and
running a few errands.

-- 
Grant Edwards                   grante             Yow! Of course, you
                                  at               UNDERSTAND about the PLAIDS
                               visi.com            in the SPIN CYCLE --


From disappearedng at gmail.com  Wed Jul 22 10:16:31 2009
From: disappearedng at gmail.com (disappearedng)
Date: Wed, 22 Jul 2009 22:16:31 +0800
Subject: Finding all cycles within an undirected graph (disappearedng)
Message-ID: <15dd54ec0907220716g34a806e1w5c2a93176172db20@mail.gmail.com>

Actually, I have realized that using the bit vector XOR method by
http://www.me.utexas.edu/~bard/IP/Handouts/cycles.pdf gives some
possibility of doing so. However this method is still experimental and
doesn't really have a definitive end to the algorithm (the base number
of vectors can change).

Any ideas anyone?

On Wed, Jul 22, 2009 at 9:12 PM, <python-list-request at python.org> wrote:
> Send Python-list mailing list submissions to
> ? ? ? ?python-list at python.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
> ? ? ? ?http://mail.python.org/mailman/listinfo/python-list
> or, via email, send a message with subject or body 'help' to
> ? ? ? ?python-list-request at python.org
>
> You can reach the person managing the list at
> ? ? ? ?python-list-owner at python.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Python-list digest..."
>
> Today's Topics:
>
> ? 1. Finding all cycles within an undirected graph (disappearedng)
> ? 2. Re: Re: Changing the private variables content (Xavier Ho)
> ? 3. Python-URL! - weekly Python news and links (Jul 22)
> ? ? ?(Gabriel Genellina)
> ? 4. Re: Multiple versions of python (Dave Angel)
> ? 5. Re: Changing the private variables content (MRAB)
>
>
> ---------- Forwarded message ----------
> From:?disappearedng <disappearedng at gmail.com>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 21:04:18 +0800
> Subject:?Finding all cycles within an undirected graph
> Hey everyone,
> I am interested to find out all the cycles within an undirected graph.
> I don't have a particular implementation of nodes and vertices yet, so
> would someone kindly point out a good graph library for this ( I
> looked at pygraph and python-graph, but not really satisfied ), in
> addition to good algorithm for solving this issue.
>
>
>
> ---------- Forwarded message ----------
> From:?Xavier Ho <contact at xavierho.com>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 23:06:22 +1000
> Subject:?Re: Re: Changing the private variables content
> Got it:
>
> exec('self.' + attr + '=\'' + val + '\'')
>
> That worked. I think it'll do what you want now ;)
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
>
> ---------- Forwarded message ----------
> From:?"Gabriel Genellina" <python-url at phaseit.net>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 12:48:25 +0000 (UTC)
> Subject:?Python-URL! - weekly Python news and links (Jul 22)
> QOTW: ?"If programming is symbol manipulation, then you should remember that
> the user interface is also symbol manipulation, and it is a MUCH harder
> problem than databases, sorting, searching, and all the other problems you
> learn about in academia. The user interface has to communicate over a rich
> but noisy channel using multiple under-specified protocols to a couple of
> pounds of meat which processes information using buggy heuristics evolved
> over millions of years to find the ripe fruit, avoid being eaten, and have
> sex. If you think getting XML was hard, that's *nothing* compared to user
> interfaces.
>
> The fact that even bad UIs work at all is a credit to the heuristics, bugs
> and all, in the meat." - Steven D'Aprano
> ? ? http://groups.google.com/group/comp.lang.python/msg/8c65eacbd76e79cf
>
>
> ? ?Invoke the same method over every object in a collection:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/8fd293a9b39c8733/
>
> ? ?There is no 'xor' boolean operator, why? What should be its outcome?
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/16eec722310e75e8/
>
> ? ?A thread-safe method to create unique identifiers (not necesarily
> ? ?increasing integers):
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/dfe22a6446c057df/
>
> ? ?Tim Chase tells us three ways to turn standard output into unbuffered mode:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/a65f71444bd4bb53/
>
> ? ?How to receive data of unknown length using sockets:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/9e4a9f8b6e83320/
>
> ? ?Override a method, but keeping the inherited docstring:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/1e4075ba10dcbdd9/
>
> ? ?Limiting the execution time of a code fragment:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/734054de170e2904/
>
> ? ?Sharing a big object between processes using the multiprocessing module:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/833d4988b7af6353/
>
> ? ?Why aren't OrderedDicts [3.1] comparable using <, >, <=, >=?
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/c3c6f4fe7b6d487d/
>
> ? ?So many ways to call a function - why is that? Beginners get confused:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/3fd57f5ee4850530/
>
> ? ?The reasons to choose your favorite programming language (Python, I
> ? ?presume!):
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/5d87008e328efcf9/
>
> ? ?Tuples, lists, their differences and motivation:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/cb0cf56c52321ccc/
>
>
> ========================================================================
> Everything Python-related you want is probably one or two clicks away in
> these pages:
>
> ? ?Python.org's Python Language Website is the traditional
> ? ?center of Pythonia
> ? ? ? ?http://www.python.org
> ? ?Notice especially the master FAQ
> ? ? ? ?http://www.python.org/doc/FAQ.html
>
> ? ?PythonWare complements the digest you're reading with the
> ? ?marvelous daily python url
> ? ? ? ? http://www.pythonware.com/daily
>
> ? ?Just beginning with Python? ?This page is a great place to start:
> ? ? ? ?http://wiki.python.org/moin/BeginnersGuide/Programmers
>
> ? ?The Python Papers aims to publish "the efforts of Python enthusiasts":
> ? ? ? ?http://pythonpapers.org/
> ? ?The Python Magazine is a technical monthly devoted to Python:
> ? ? ? ?http://pythonmagazine.com
>
> ? ?Readers have recommended the "Planet" sites:
> ? ? ? ?http://planetpython.org
> ? ? ? ?http://planet.python.org
>
> ? ?comp.lang.python.announce announces new Python software. ?Be
> ? ?sure to scan this newsgroup weekly.
> ? ? ? ?http://groups.google.com/group/comp.lang.python.announce/topics
>
> ? ?Python411 indexes "podcasts ... to help people learn Python ..."
> ? ?Updates appear more-than-weekly:
> ? ? ? ?http://www.awaretek.com/python/index.html
>
> ? ?The Python Package Index catalogues packages.
> ? ? ? ?http://www.python.org/pypi/
>
> ? ?Much of Python's real work takes place on Special-Interest Group
> ? ?mailing lists
> ? ? ? ?http://www.python.org/sigs/
>
> ? ?Python Success Stories--from air-traffic control to on-line
> ? ?match-making--can inspire you or decision-makers to whom you're
> ? ?subject with a vision of what the language makes practical.
> ? ? ? ?http://www.pythonology.com/success
>
> ? ?The Python Software Foundation (PSF) has replaced the Python
> ? ?Consortium as an independent nexus of activity. ?It has official
> ? ?responsibility for Python's development and maintenance.
> ? ? ? ?http://www.python.org/psf/
> ? ?Among the ways you can support PSF is with a donation.
> ? ? ? ?http://www.python.org/psf/donations/
>
> ? ?The Summary of Python Tracker Issues is an automatically generated
> ? ?report summarizing new bugs, closed ones, and patch submissions.
> ? ? ? ?http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date
>
> ? ?Although unmaintained since 2002, the Cetus collection of Python
> ? ?hyperlinks retains a few gems.
> ? ? ? ?http://www.cetus-links.org/oo_python.html
>
> ? ?Python FAQTS
> ? ? ? ?http://python.faqts.com/
>
> ? ?The Cookbook is a collaborative effort to capture useful and
> ? ?interesting recipes.
> ? ? ? ?http://code.activestate.com/recipes/langs/python/
>
> ? ?Many Python conferences around the world are in preparation.
> ? ?Watch this space for links to them.
>
> ? ?Among several Python-oriented RSS/RDF feeds available, see:
> ? ? ? ?http://www.python.org/channews.rdf
> ? ?For more, see:
> ? ? ? ?http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
> ? ?The old Python "To-Do List" now lives principally in a
> ? ?SourceForge reincarnation.
> ? ? ? ?http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
> ? ? ? ?http://www.python.org/dev/peps/pep-0042/
>
> ? ?del.icio.us presents an intriguing approach to reference commentary.
> ? ?It already aggregates quite a bit of Python intelligence.
> ? ? ? ?http://del.icio.us/tag/python
>
> ? ?Enjoy the *Python Magazine*.
> ? ? ? ?http://pymag.phparch.com/
>
> ? ?*Py: the Journal of the Python Language*
> ? ? ? ?http://www.pyzine.com
>
> ? ?Dr.Dobb's Portal is another source of Python news and articles:
> ? ? ? ?http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
> ? ?and Python articles regularly appear at IBM DeveloperWorks:
> ? ? ? ?http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8
>
> Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
> ?http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
> ?http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
> ?http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes
>
> There is *not* an RSS for "Python-URL!"--at least not yet. ?Arguments
> for and against are occasionally entertained.
>
>
> Suggestions/corrections for next week's posting are always welcome.
> E-mail to <Python-URL at phaseit.net> should get through.
>
> To receive a new issue of this posting in e-mail each Monday morning
> (approximately), ask <claird at phaseit.net> to subscribe. ?Mention
> "Python-URL!". ?Write to the same address to unsubscribe.
>
>
> -- The Python-URL! Team--
>
> Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
> sponsor the "Python-URL!" project. ?Watch this space for upcoming
> news about posting archives.
>
>
>
> ---------- Forwarded message ----------
> From:?Dave Angel <davea at ieee.org>
> To:?CCW <c.c.wood at gmail.com>
> Date:?Wed, 22 Jul 2009 09:11:26 -0400
> Subject:?Re: Multiple versions of python
> CCW wrote:
>>
>> On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
>>
>>>
>>> ChrisW wrote:
>>>
>>>>
>>>> Hi,
>>>> ? ? ?I have installed 2 versions of python on my Windows XP computer - I
>>>> originally had 3.0.1, but then found that the MySQL module only
>>>> supported 2.*, so I've now installed that. ?I have found that if I
>>>> change the Windows Environment Variable path, then I can change the
>>>> version of python called when I type 'python' into a command line.
>>>> However, I'd like to be able to choose which version I use. ?I know
>>>> that if I change C:\Python26\python.exe to
>>>> C:\Python26\python2.exe and C:\Python30\python.exe to C:
>>>> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
>>>> the correct interpreter. ?However, is it safe just to rename the
>>>> executable files? Is there a more elegant way to achieve the same
>>>> task?
>>>> ? ? ?Thanks,
>>>> Chris
>>>>
>>>
>>> The elegant way is to have a batch directory on your PATH ( I use ?m:\t\bat ) ?and put your *.bat files there. ? I do NOT put any python
>>> installations on the PATH.
>>>
>>> For example, I have a batch file called: ? ? m:\t\bat\python26.bat
>>>
>>> c:\progfiles\python26\python.exe %*
>>>
>>> The %* syntax means pass all arguments through to the program.
>>>
>>> Once it all works, you can add an "@" in front of the c: ? in order to
>>> suppress echoing the command. ?At that point, it'll look and work the
>>> same way as what you did, but without modifying anything in the install
>>> directory. ? ?(You may want ?python26.bat, pythonw26.bat, python31.bat
>>> and pythonw31.bat)
>>>
>>> The other thing you may want to do in a batch file is to change the file
>>> associations so that you can run the .py file directly, without typing
>>> "python" or "pythonw" in front of it.
>>>
>>> The relevant Windows commands are: ? ? assoc and ftype ? ? ?And on a
>>> related note, you may want to edit the PATHEXT environment variable, to
>>> add .PY and .PYW
>>>
>>
>> Thanks for this - this way made a bit more sense to me. ?I've now got
>> C:\commands with the 4 .bat files in, and C:\commands in my path. ?It
>> all seems to work :) I think I've missed the point of the @ though -
>> it doesn't seem to make any difference..
>>
>> I'm also a bit confused with the associations - since I've got python
>> 2.6 and 3.1, surely the command I type (python26 or python31) is the
>> only way to force a script to be run using a specific interpreter at
>> runtime without having to change the .bat file every time I want to
>> run a script using 3.1 instead of 2.6?
>>
>>
>
> The @ symbol was used in older versions of CMD and COMMAND to suppress echoing of the command line. ?I think if you're using XP or later, it doesn't matter.
>
> As for file associations, I don't know just what you already know about. ?When you type ? ?data.doc ? ?at a command line, the system looks for the data file, then if it's found, it looks up the program associated with that extension. ?On my machine, that's a particular version of Word for Windows. ?Similarly, if I type ? ?digest.py ? and I'm in the directory containing that file, the system looks up my associations, and runs Python 2.6 on that file. ?If I wanted it to run Python 3.1 on that file, I'd have to change the associations, temporarily.
>
> So, first approximation, it's a way to avoid having to type PYTHON each time I want to run a script, as long as I don't need any other arguments on the (implied) command line. ?Further, the system will then look for digest.py everywhere on the PATH, so I don't even have to be in the same directory. ?And that means I can be in the data directory that digest.py is going to work on. ?Effectively, it raises digest.py to feeling like an executable, for most purposes. ?In fact, I put all my scripts in a directory, along with other simple executables. ? I use ?m:\t\bin ?for that purpose.
>
> These associations (to .py and .pyw) are established by the installer program for Python. ?But when you had multiple installs, you could choose whether the second one installed overrides the first. ?My point is that if you need to change them back and forth, you could use ?assoc and ftype to do it.
>
> On my system:
>
> M:\LabOrders>assoc .py
> .py=Python.File
>
> M:\LabOrders>ftype Python.File
> Python.File="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*
>
> M:\LabOrders>
>
>
> So my .py files are associated with the 2.6.2 version of ActivePython installation. ? Note the similarity of the ftype to your python26.bat file?
>
> One more little trick is that I could just type ? digest ? ?instead of ? ?digest.py, ? if I have added the .py and .pyw extensions to my ? PATHEXT environment variable. ? ?So my PATHEXT looks like:
> ?PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.PY;.PYW
>
>
>
> Note that the association changes made by ?assoc and ftype are global. ?They apply to all cmd.exe windows, even those already running, and they survive a reboot. ?But when you set environment variables like PATHEXT, ?you can choose to do it in a single window (with SET), or globally (using control-panel).
>
> If I found myself switching often, I'd make separate ftype entries for each interpreter, something like
> ?Python.File26="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*
> ?Python.File31="C:\PROGFI~1\.....
> and just change assoc .py ?to point at the one I needed today.
>
> As it is, I'm content leaving the associations pointing at 2.6, and explicitly entering PYTHON31 in front of any script name I want to run on that interpreter.
>
> DaveA
>
>
>
>
> ---------- Forwarded message ----------
> From:?MRAB <python at mrabarnett.plus.com>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 14:12:18 +0100
> Subject:?Re: Changing the private variables content
> Ryniek90 wrote:
>>>
>>> ------------------------------------------------------------------------
>>>
>>> Temat:
>>> Re: Changing the private variables content
>>> Od:
>>> Gary Herron <gherron at islandtraining.com>
>>> Data:
>>> Tue, 21 Jul 2009 14:14:44 -0700
>>> Do:
>>> Ryniek90 <ryniek90 at gmail.com>
>>>
>>> Do:
>>> Ryniek90 <ryniek90 at gmail.com>
>>> Kopia:
>>> python-list at python.org
>>>
>>>
>>> Ryniek90 wrote:
>>>>
>>>> Hi.
>>>> I'm writing some class, and decided to use inside private method and some private variables. While with method i haven't got any problem's with variables i have.
>>>> Maybe some example.
>>>> A class with private method and private variable:
>>>>
>>>> "
>>>> >>> class Secret(object):
>>>> ? #
>>>> ? def __init__(self):
>>>> ? ? ? self._number = 1
>>>> ? #
>>>> ? def _secret(self):
>>>> ? ? ? print self._number
>>>> ? def showit(self):
>>>> ? ? ? print "Secret number is:\n"
>>>> ? ? ? self._secret()
>>>>
>>>> >>> sec = Secret()
>>>> >>> sec.showit()
>>>> Secret number is:
>>>>
>>>> 1
>>>> >>> sec._number
>>>> 1
>>>> >>> sec._number = 2
>>>> >>> sec._number
>>>> 2
>>>> >>> sec._number += 3
>>>> >>> sec._number
>>>> 5
>>>> >>>
>>>> "
>>>>
>>>> As You can see, i made class with private method and private variable inside __init__ constructor. I've changed also the variable value, but outside class.
>>>> I've got problem with changing some variable value _inside__my_ class, which i'm writing.
>>>
>>> Not sure this is what you are asking, but a method (which is how I interpret "_inside__my_ class") changes the value by normal assignment like this:
>>>
>>> class Secret(object):
>>> ?...
>>> ?def SetNumber(self,value):
>>> ? self._number = value
>>>
>>> Is that what you were asking?
>>>
>>>
>>> Gary Herron
>>>
>>>
>>>
>>>> I've searched over google, some tuts with topics about operations on private variables, but didn't found anything - only how to make them, but no how to assign new objects/override them with new content (and other advanced and helpful options).
>>>>
>>>> If someone could help me, it would be great.
>>>>
>>>> Thanks.
>>>
>>>
>>
>>
>> Thanks for hint, but looks like i can't do what i want.
>>
>> Maybe i show You my class:
>>
>> "
>>
>> class ModPrint(object):
>> ? ? u"""
>> ? This will be the doc.
>> ? """
>> ? ? def __init__(self):
>> ? ? ? ? ? ? #Assign the Python installation directory - sys.exec_prefix - to variable
>> ? ? ? self._default_search_path=sys.exec_prefix
>> ? ? ? self._chosen_module = ''
>> ? ? ? self._user_search_path = ''
>> ? ? ? self._this_module = ''
>> ? ? ? ? def _SetVar(self, attr, val):
>> ? ? ? self.attr = val ? ? ? ? ? ?def _search_for_module(self, *args):
>> ? ? ? ? ? ? """Private method which walks through default Python installation directories, and search for prefered module."""
>> ? ? ? ? ? ? #walking thru all directories available in path '_user_search_path'
>> ? ? ? for root, dirs, files in os.walk(self._user_search_path):
>> ? ? ? ? ? for f in files:
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? #if found file 'f' is THAT module,
>> ? ? ? ? ? ? ? #full path to THAT file is assigned to variable
>> ? ? ? ? ? ? ? if f == ("%s.py" % self._chosen_module):
>> ? ? ? ? ? ? ? ? ? self._SetVar(self._this_module, os.path.join(root, f))
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? def print_module(self, _chosen_module='', _user_search_path='', _default_search_path=sys.exec_prefix,):
>> ? ? ? ? ? ? """Reads module chosen by user, and returns full content of this module, as it is."""
>> ? ? ? ? ? ? ? ? ? #if custom search path hasn't been assigned,
>> ? ? ? #default path is being assigned as custom path
>> ? ? ? if self._user_search_path == '':
>> ? ? ? ? ? self._user_search_path = self._default_search_path
>> ? ? ? ? ? ? ? ? #using private method '_search_for_module' with 'self.' preffix
>> ? ? ? #to search for prefered module
>> ? ? ? self._search_for_module(_chosen_module, _user_search_path)
>> ? ? ? ? ? ? #opening prefered module with read-only binary mode
>> ? ? ? #and assigning it to 'module_open' variable
>> ? ? ? module_open = open(self._this_module, 'rb')
>> ? ? ? ? ? ? #reading this file and assigning it to variable
>> ? ? ? module_text = module_open.read()
>> ? ? ? ? ? ? #closing read file; the read content is still available
>> ? ? ? #it's stored in variable 'module_text'
>> ? ? ? module_open.close()
>> ? ? ? ? ? ? #returning the read content
>> ? ? ? return module_text
>>
>> "
>>
>> When i use this class in Python IDLE, i've got this error:
>> "
>> ?>>> mod = ModPrint()
>> ?>>> import socket
>> ?>>> mod.print_module('socket')
>>
>> Traceback (most recent call last):
>> ?File "<pyshell#60>", line 1, in <module>
>> ? mod.print_module('socket')
>> ?File "<pyshell#57>", line 48, in print_module
>> ? module_open = open(self._this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>> ?>>>
>> "
>>
>> As You can see, i can't assign the new value "os.path.join(root, f)" to the 'self._this_module variable'.
>> So for sure i've made some mistake in method:
>>
>> "
>> def _SetVar(self, attr, val):
>> ? ? ? self.attr = val ? "
>> When i've changed private variables to normal, stored in class (in __init__ method), it was the same situation - i couldn't change this variable value.
>>
>> "
>> ?>>> mod = ModPrint()
>> ?>>> mod.print_module('os')
>>
>> Traceback (most recent call last):
>> ?File "<pyshell#72>", line 1, in <module>
>> ? mod.print_module('os')
>> ?File "<pyshell#64>", line 48, in print_module
>> ? module_open = open(self.this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>> ?>>>
>> "
>>
>> Thanks i someone could help me, give some hint.
>
> What is the point of the _SetVar method?
>
> Instead of:
>
> ? ?self._SetVar(self._this_module, os.path.join(root, f))
>
> just do:
>
> ? ?self._this_module = os.path.join(root, f)
>
> (unless I'm misunderstanding what you're trying to do!)
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From inky788 at gmail.com  Wed Jul 22 10:36:51 2009
From: inky788 at gmail.com (Inky 788)
Date: Wed, 22 Jul 2009 07:36:51 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com> 
	<mailman.3511.1248244497.8015.python-list@python.org>
Message-ID: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>

On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>
> > On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
>
> > wrote:
> > > [snip] We
> > > understand that lists are mutable and tuples are not, but we're a
> > > little lost as to why the two were kept separate from the start. They
> > > both perform a very similar job as far as we can tell.
>
> > My guess is that it was probably for optimization reasons long ago.
> > I've never heard a *good* reason why Python needs both.
>
> The good reason is the immutability, which lets you use
> a tuple as a dict key. ?

Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
just not sophisticated enough, but I've never wanted to use a list/
tuple as a dict key. This sounds like obscure usage, and a bit
contrived as a reason for having *both* lists and tuples.


From davea at ieee.org  Wed Jul 22 10:38:14 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 10:38:14 -0400
Subject: Ideas for problem with chat server application!
In-Reply-To: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
References: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
Message-ID: <4A672456.9010604@ieee.org>

David Adamo Jr. wrote:
> I developed a chat application with an attendant chat server.
> Everything is working fine. The issue now is the fact that whenever
> the chat server goes down (for instance, the server system shuts down
> as a result of power failure or some other problem), by the time the
> server system come back on, the chat server would have to be restarted
> manually.
>
> I believe (and I know) it is more appropriate for the chat server
> application to restart itself when the computer comes back on (and of
> course regardless of who is logged in and of course, even before
> anyone logs in). I have a batch file that executes the chat server. My
> attempt was to create a windows service that start automatically and
> runs this batch file using a Network Service account on the server
> system. Although, I'm having a hard time with this (temporarily), I
> would love to ask if there are any alternatives to using a windows
> service. Suggestions are highly appreciated.
>
>   
As a starting place, take a look at the Windows Scheduler.  One of the 
options is to schedule something at "boot."  That happens before anybody 
logs on to the system.  I don't know whether you can specify what user 
account will be used, but you can certainly launch a python program from 
there.

DaveA


From inky788 at gmail.com  Wed Jul 22 10:46:06 2009
From: inky788 at gmail.com (Inky 788)
Date: Wed, 22 Jul 2009 07:46:06 -0700 (PDT)
Subject: Documentation Problems
References: <h46rpv$lm5$1@adenine.netfront.net>
	<mailman.3518.1248261276.8015.python-list@python.org>
Message-ID: <b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>

On Jul 22, 7:15?am, Tim Golden <m... at timgolden.me.uk> wrote:
> Mark du Preez wrote:
> > Hi
>
> > Can anyone tell me where to go to suggest changes to the Python
> > documentation?
>
> Drop an entry in the tracker:
>
> ?http://bugs.python.org
>
> Patches are always welcome,

Could you please provide brief instructions on exactly how to go about
creating a suitable patch file? I mean, starting from the beginning
(as in, "check out code from {here} using {this command}", "cd to
{this} directory", "edit the file in place", "run {this} command to
create a patch file"). Or perhaps this procedure is already outlined
elsewhere?


From f.orndorffplunkett at gmail.com  Wed Jul 22 10:46:09 2009
From: f.orndorffplunkett at gmail.com (F.O.P.)
Date: Wed, 22 Jul 2009 07:46:09 -0700 (PDT)
Subject: Not understanding this documentation
Message-ID: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>

http://bugs.python.org/issue5358
I simply installed 3.0 on my ubuntubox brought my project from a
windows machine and made necessary changes to what I had used from os
and os.path.  I have an error at the end of this line:
for k in range(I):
and the error:
SyntaxError: invalid character in identifier

I've already declared I way above as the lenth of an array (I = len
(IA))
There shouldn't be a problem there aren't any issues with other
declarations identical to this.


From george.sakkis at gmail.com  Wed Jul 22 10:55:38 2009
From: george.sakkis at gmail.com (George Sakkis)
Date: Wed, 22 Jul 2009 07:55:38 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
Message-ID: <10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>

On Jul 22, 7:38?am, William Dode <w... at flibuste.net> wrote:

> I updated the script (python, c and java) with your unrolled version
> + somes litle thinks.
>
> I also tried with python3.1, unladen Q2, ironpython1.1.1
>
> Unfortunately it doesn't work more with shedskin, i'll see on the
> shedskin group...
>
> c 1.85s
> gcj 2.15s
> java 2.8s
> python2.5 + psyco 3.1s
> unladen-2009Q2 145s (2m45)
> python2.5 254s (4m14s)
> python3.1 300s (5m)
> ironpython1.1.1 680s (11m20)

Cool; it would be interesting to see the numbers for Jython and Boo as
well if it's not too much effort.

George


From kyrie at uh.cu  Wed Jul 22 11:01:20 2009
From: kyrie at uh.cu (Luis Alberto Zarrabeitia Gomez)
Date: Wed, 22 Jul 2009 11:01:20 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <1248274880.4a6729c036a68@comuh.uh.cu>


Quoting Inky 788 <inky788 at gmail.com>:

> > The good reason is the immutability, which lets you use
> > a tuple as a dict key. ?
> 
> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

I don't seem to understand your definition of obscure and contrived. It seems
that you got late to this thread, and you missed the examples. I'd suggest you
to go back on this thread and look at them. 


heights = {}
heights[1,2] = 5
heights[1,3] = 7
heights[3,5] = 1

addresses[lastname, firstname] = my_home_address

census[location, age] = census.get((location, age), 0) + 1

All those are using tuples as dict keys.

Regards,

-- 
Luis Zarrabeitia
Facultad de Matem?tica y Computaci?n, UH
http://profesores.matcom.uh.cu/~kyrie


-- 
Participe en Universidad 2010, del 8 al 12 de febrero de 2010
La Habana, Cuba 
http://www.universidad2010.cu



From rhodri at wildebst.demon.co.uk  Wed Jul 22 11:07:53 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 22 Jul 2009 16:07:53 +0100
Subject: Not understanding this documentation
In-Reply-To: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
Message-ID: <op.uxg5nfk3a8ncjz@gnudebst>

On Wed, 22 Jul 2009 15:46:09 +0100, F.O.P. <f.orndorffplunkett at gmail.com>  
wrote:

> http://bugs.python.org/issue5358
> I simply installed 3.0 on my ubuntubox brought my project from a
> windows machine and made necessary changes to what I had used from os
> and os.path.  I have an error at the end of this line:
> for k in range(I):
> and the error:
> SyntaxError: invalid character in identifier
>
> I've already declared I way above as the lenth of an array (I = len
> (IA))
> There shouldn't be a problem there aren't any issues with other
> declarations identical to this.

Could you show us slightly more of your code and the rest of the
error message, please?  I have a suspicion that the error actually
lies in the "necessary changes" you made.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From phillip.oldham at gmail.com  Wed Jul 22 11:09:31 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Wed, 22 Jul 2009 08:09:31 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com>
Message-ID: <123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com>

On Jul 22, 2:23?pm, Casey Webster <Casey... at gmail.com> wrote:
> I can't answer your question, but I would like to better understand
> the
> problem you are trying to solve. ?The Apache Hadoop/MapReduce java
> application isn't really that "large" by modern standards, although it
> is generally run with large heap sizes for performance (-Xmx1024m or
> larger for the mapred.child.java.opts parameter).
>
> MapReduce is designed to do extremely fast parallel data set
> processing
> on terabytes of data over hundreds of physical nodes; what advantage
> would a pure Python approach have here?

We're always taught that it is a good idea to reduce the number of
dependencies for a project. So you could use Disco, or Dumbo, or even
Skynet. But then you've introduced another system you have to manage.
Each new system will have a learning curve, which is lessened if the
system is written in an environment/language you already work with/
understand. And since a large cost with environments like erlang and
java is in understanding them any issues that are out of the ordinary
can be killer; changing the heap size as you mentioned above for Java
could be one of these issues that a non-java dev trying to use Hadoop
might come across.

With the advent of cloud computing and the new semi-structured/
document databases that are coming to the fore sometimes you need to
use MapReduce on smaller/fewer systems to the same effect. Also, you
may need only to ensure that a job is done in a timely fashion without
taking up too many resources, rather than lightening-fast. Dumbo/disco
in these situations may be considered overkill.

Implementations like BashReduce <http://blog.last.fm/2009/04/06/
mapreduce-bash-script> are perfect for such scenarios. I'm simply
wondering if there's another simpler/smaller implementation of
MapReduce that plays nicely with Python but doesn't require the setup/
knowledge overhead of more "robust" implementations such as hadoop and
disco... maybe similar to Ruby's Skynet.


From davea at ieee.org  Wed Jul 22 11:10:35 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 11:10:35 -0400
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <4A672BEB.6010008@ieee.org>

superpollo wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">hello clp.
>
> i can insert a hex value for a character literal in a string:
>
> >>> stuff = "\x45"
> >>> print stuff
> E
> >>>
>
> can i do something like the above, but using a *binary* number? (e.g. 
> 00101101 instead of 45) ?
>
> bye
>
> </div>
>
There's no way to get a binary value directly into a literal, but you 
can convert one into a string value, as follows:


x = 0b00101101
print x
print chr(x)

output is:
  45
  -

Note that this is decimal 45, which is different than the hex 45 you 
used in your first example.

For doing multiple characters, I can't see anything better than:

lis = [0b00101101, 0b01000101, 0b01100001]
print lis
s= "".join(chr(x) for x in lis)
print s

DaveA



From hackingkk at gmail.com  Wed Jul 22 11:35:19 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Wed, 22 Jul 2009 21:05:19 +0530
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
Message-ID: <1248276919.8402.6.camel@krishna-laptop>

hello all,
This is a real challenge and I don't know if a solution even exists for
this or not.

I am writing an application which I run as my usual user on ubuntu.
the usernake is let's say kk and it has sudo permission (meaning the
user is in the sudoers list ).


now when i do python myscript.py, the script has to change to another
non-privileged user for some tasks.
let's say for example switch to the postgres user which is dedicated for
postgres and has no other privileges.

I have tryed doing os.setuid(112) where 112 could be the uid of the user
I want the script to swith over.


but I got opperation not permitted.

I tryed using subprocess but that did not help me either.  I tryed sudo
su into the Popen command but it throws me into the terminal (shell)
with postgres as the user.

But that's now my desired result.
what I exactly want is that the script now continues to execute under
postgres user till the end.

I don't know how to achieve this iffect.

Infact I will need this during a serious deployment because i would have
my application run as a demon as a dedicated user.

I am finding some code for deamonising a python application but don't
know how to tell the script to change user.

happy hacking.
Krishnakant.




From davea at ieee.org  Wed Jul 22 11:39:51 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 11:39:51 -0400
Subject: Changing the private variables content
In-Reply-To: <4A671BAF.1060204@gmail.com>
References: <mailman.13388.1248268320.8014.python-list@python.org>
	<4A671BAF.1060204@gmail.com>
Message-ID: <4A6732C7.7070909@ieee.org>

Ryniek90 wrote:
> <snip>
>
>
> It looks like private variable have specific naure, that prevent from 
> traditional editing them.
> Still searching for some tuts about private methods and variables.
>
>
There's no tutorial on private variables for good reason:

Private variables have no special characteristics.  The compiler and 
runtime library don't treat them specially (except for the highly 
controversial from xx import *).  It's strictly a programming 
convention.  You've got some other bugs in your code, which I can't help 
you with because your code comes across formatted so strangely that it 
cannot compile here.  Some things you might do to make it easier to get 
help:

1) make sure you're not mixing tabs and spaces in your source code
2) post using text messages, so they don't get reformatted.
3) copy/paste the code and error messages into your message, don't retype.
4) whenever you've made more than trivial changes to the code, repost it 
all, since it's very difficult to tell which suggestions you've 
followed, and which ones you haven't gotten yet, or maybe dismissed 
because they didn't work.

DaveA



From python at bdurham.com  Wed Jul 22 11:42:07 2009
From: python at bdurham.com (python at bdurham.com)
Date: Wed, 22 Jul 2009 11:42:07 -0400
Subject: Suggestions for Python MapReduce?
In-Reply-To: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
Message-ID: <1248277327.15700.1326268767@webmail.messagingengine.com>

Phillip,

We've had great success writing simple, project specific algorithms to
split content into chunks appropriate for ETL type, Python based
processing in a hosted cloud environment like Amazon EC2 or the recently
launched Rackspace Cloud Servers. Since we're purchasing our cloud
hosting time in 1 hour blocks, we divide our data into much larger
chunks than what a traditional map-reduce technique might use. For many
of our projects, the data transfer time to and from the cloud takes the
majority of clock time.

Malcolm


From jeanmichel at sequans.com  Wed Jul 22 12:07:07 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 22 Jul 2009 18:07:07 +0200
Subject: Changing the private variables content
In-Reply-To: <02770500$0$5185$c3e8da3@news.astraweb.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>	<mailman.3521.1248265771.8015.python-list@python.org>
	<02770500$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A67392B.3090602@sequans.com>

Steven D'Aprano wrote:
> On Wed, 22 Jul 2009 14:29:20 +0200, Ryniek90 wrote:
>
>   
>> When i use this class in Python IDLE, i've got this error: "
>>     
> ...
>   
>> Traceback (most recent call last):
>>   File "<pyshell#60>", line 1, in <module>
>>     mod.print_module('socket')
>>   File "<pyshell#57>", line 48, in print_module
>>     module_open = open(self._this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>>  >>>
>> "
>>
>> As You can see, i can't assign the new value "os.path.join(root, f)" to
>> the 'self._this_module variable'.
>>     
>
> In the __init__ method, you successfully set the `_this_module` attribute:
>
>         self._this_module = ''
>
> That works, so it proves that you *can* set a private attribute.
>
> Later on, you call the `_SetVar` method, which does this:
>
>     def _SetVar(self, attr, val):
>         self.attr = val   
>
> In English, this method does this:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute named exactly "attr".
>
> What you actually want is:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute with the name stored 
> in the variable "attr".
>
> Can you see the difference?
>
> What you actually want is:
>
>     def _SetVar(self, attr, val):
>         setattr(self, attr, val)
>
>
> Your code is terribly complicated. This will probably do what you want. 
> (Warning -- I haven't tested it, so there may be a few errors.)
>
>
> class ModPrint(object):
>     u"""
>     This will be the doc.
>     """
>     def __init__(self, default_search_path=''):
>         self.default_search_path = ''
>
>    def find_module(self, modulename, search_path=''):
>        if search_path == '':
>            # Try the default search path instead.
>            search_path = self.default_search_path
>         if search_path == '':  # still blank.
>             # Try the Python search path instead.
>            search_path = sys.exec_prefix
>         for root, dirs, files in os.walk(search_path):
>             for f in files:
>                 if f == "%s.py" % modulename:
>                     return os.path.join(root, f)
>
>     def get_module_text(self, modulename, search_path=''):
>         filename = self.find_module(modulename, search_path)
>         module_open = open(filename, 'rb')
>         module_text = module_open.read()
>         module_open.close()
>         return module_text
>
>
> I changed the name of print_module_text because it doesn't actually print 
> anything.
>
>
>
>   
Moreover, if I'm not wrong there is absolutely no difference in the way 
python is handling private and public attributes, for python, both are 
the same kind of attributes. This is purely conventional (some doc 
processing tool will take into account the private prefix).

So there is absolutely no restriction in writing self._myVar = 0 in any 
of the instance methods.

JM



From ryniek90 at gmail.com  Wed Jul 22 12:10:52 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 22 Jul 2009 18:10:52 +0200
Subject: Python-list Digest, Vol 70, Issue 282
In-Reply-To: <mailman.13395.1248271304.8014.python-list@python.org>
References: <mailman.13395.1248271304.8014.python-list@python.org>
Message-ID: <4A673A0C.2000807@gmail.com>

>
>> When i use this class in Python IDLE, i've got this error: "
>>     
> ...
>   
>> Traceback (most recent call last):
>>   File "<pyshell#60>", line 1, in <module>
>>     mod.print_module('socket')
>>   File "<pyshell#57>", line 48, in print_module
>>     module_open = open(self._this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>>  >>>
>> "
>>
>> As You can see, i can't assign the new value "os.path.join(root, f)" to
>> the 'self._this_module variable'.
>>     
>
> In the __init__ method, you successfully set the `_this_module` attribute:
>
>         self._this_module = ''
>
> That works, so it proves that you *can* set a private attribute.
>
> Later on, you call the `_SetVar` method, which does this:
>
>     def _SetVar(self, attr, val):
>         self.attr = val   
>
> In English, this method does this:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute named exactly "attr".
>
> What you actually want is:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute with the name stored 
> in the variable "attr".
>
> Can you see the difference?
>
> What you actually want is:
>
>     def _SetVar(self, attr, val):
>         setattr(self, attr, val)
>
>
> Your code is terribly complicated. This will probably do what you want. 
> (Warning -- I haven't tested it, so there may be a few errors.)
>
>
> class ModPrint(object):
>     u"""
>     This will be the doc.
>     """
>     def __init__(self, default_search_path=''):
>         self.default_search_path = ''
>
>    def find_module(self, modulename, search_path=''):
>        if search_path == '':
>            # Try the default search path instead.
>            search_path = self.default_search_path
>         if search_path == '':  # still blank.
>             # Try the Python search path instead.
>            search_path = sys.exec_prefix
>         for root, dirs, files in os.walk(search_path):
>             for f in files:
>                 if f == "%s.py" % modulename:
>                     return os.path.join(root, f)
>
>     def get_module_text(self, modulename, search_path=''):
>         filename = self.find_module(modulename, search_path)
>         module_open = open(filename, 'rb')
>         module_text = module_open.read()
>         module_open.close()
>         return module_text
>
>
> I changed the name of print_module_text because it doesn't actually print 
> anything.
>   

Thanks for ready class - it works great, but that code:
"

What you actually want is:

    def _SetVar(self, attr, val):
        setattr(self, attr, val)


"
Didn't worked, so i wil reuse your class, and modify it later. Now i see 
that working on private objects complex.



From junhufr at gmail.com  Wed Jul 22 12:13:37 2009
From: junhufr at gmail.com (Jun)
Date: Wed, 22 Jul 2009 09:13:37 -0700 (PDT)
Subject: Copy/paste through LAN
Message-ID: <c1e24f0f-b34f-45e8-81bd-118baa1e8632@c29g2000yqd.googlegroups.com>

Hello,

I've a client/server application which uses Pyro to communicate each
other.
Now i try to implement copy/paste through LAN between server
controlled
filesystem to my local windows machine (I could list files in client's
window).
How can i pass the url information through Pyro ?

Thank you in advance.

Jun


From tjreedy at udel.edu  Wed Jul 22 12:28:04 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:28:04 -0400
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <h47emj$ogf$1@ger.gmane.org>

superpollo wrote:
> hello clp.
> 
> i can insert a hex value for a character literal in a string:
> 
>  >>> stuff = "\x45"
>  >>> print stuff
> E
>  >>>
> 
> can i do something like the above, but using a *binary* number? (e.g. 
> 00101101 instead of 45) ?

Language Ref 2.4. Literals



From rNOSPAMon at flownet.com  Wed Jul 22 12:36:28 2009
From: rNOSPAMon at flownet.com (Ron Garret)
Date: Wed, 22 Jul 2009 09:36:28 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
Message-ID: <rNOSPAMon-7C2B71.09362722072009@news.albasani.net>

In article <uRr9m.6558$ze1.5162 at news-server.bigpond.net.au>,
 Neil Hodgson <nyamatongwe+thunder at gmail.com> wrote:

> milanj:
> 
> > and all of them use native threads (python still use green threads ?)
> 
>    Python uses native threads.

But then it adds the global interpreter lock, which completely 
undermines the utility of native threads.  So yes, it uses native 
threads, but it does not actually realize the benefits of that use.

rg


From sjmachin at lexicon.net  Wed Jul 22 12:37:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 22 Jul 2009 09:37:16 -0700 (PDT)
Subject: Not understanding this documentation
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
Message-ID: <dd96ba46-a411-4b51-9c73-a0dea2da680d@g1g2000pra.googlegroups.com>

On Jul 23, 12:46?am, "F.O.P." <f.orndorffplunk... at gmail.com> wrote:
> http://bugs.python.org/issue5358
> I simply installed 3.0 on my ubuntubox brought my project from a
> windows machine and made necessary changes to what I had used from os
> and os.path. ?I have an error at the end of this line:
> for k in range(I):
> and the error:
> SyntaxError: invalid character in identifier
>
> I've already declared I way above as the lenth of an array (I = len
> (IA))
> There shouldn't be a problem there aren't any issues with other
> declarations identical to this.

You are have used the --ftniv and --strict  options and hence it's
objecting to the lower-case "k".



From tjreedy at udel.edu  Wed Jul 22 12:38:22 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:38:22 -0400
Subject: Documentation Problems
In-Reply-To: <7coan1F28i1q2U1@mid.uni-berlin.de>
References: <h46rpv$lm5$1@adenine.netfront.net>
	<7coan1F28i1q2U1@mid.uni-berlin.de>
Message-ID: <h47f9u$sko$1@ger.gmane.org>

Diez B. Roggisch wrote:
> Mark du Preez wrote:
> 
>> Hi
>>
>> Can anyone tell me where to go to suggest changes to the Python
>> documentation?
>>
>> Thanks.
> 
> http://docs.python.org/ has a "bugs"-section that leads to
> 
> http://docs.python.org/bugs.html
> 
> You can file doc-bugs in the tracker, and check if they are already fixed in
> the dev-docs.

Actually, check first at

http://docs.python.org/dev/py3k/     for 3.2a
http://docs.python.org/dev/          for 2.7a

These are updated often, perhaps nightly.
Then file if you still think a change is needed.

For small changes, a specific suggested rewording is sufficient.

"Change 'tihs' to 'this'."

"Between 'Sentence 1' and 'sentence 2', I suggest adding 'sentence 3'."

The doc maintainers are happy to do the rst formatting themselves.



From tjreedy at udel.edu  Wed Jul 22 12:44:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:44:08 -0400
Subject: doted filenames in import statements
In-Reply-To: <4A670313.8040204@sequans.com>
References: <mailman.3488.1248212574.8015.python-list@python.org>	<m2prbtllen.fsf@cs.uu.nl>
	<4A670313.8040204@sequans.com>
Message-ID: <h47fko$tqp$1@ger.gmane.org>

Jean-Michel Pichavant wrote:
> Piet van Oostrum wrote:
>>
>> [snip]
>>
>>> JP> file = "/home/dsp/4.6.0.0/test.py"
>>> JP> test = __import__(file)
>>> JP> => no module name blalalal found.
>>>     
>>
>>  
>>> JP> Any suggestion ? I tried multiple escape technics without any 
>>> success.
>>>     
>>
>> Rightly so.
>>
>> I think the best would be to add the directory to sys.path 
>> sys.path.add('/home/dsp/4.6.0.0')
>> and then
>> __import__('test', ... )   
> 
> I see. My problem is that a have to import 2 different files having de 
> same name. In the same name space I have 2 objects from 2 different 
> software branches, let's say 4.6.0 and 4.6.1.
> The first object shall import 4.6.0/orb.py and the second one 4.6.1/orb.py.
> 
> If I add 4.6.1 to sys.path, the import statement will look like:
> self._orb = __import__('orb')
> The problem is, python wil assume orb is already imported and will 
> assign the module from the 4.6.0 branch to my 4.6.1 object.
> 
> Do I have to mess up with sys.modules keys to make python import the 
> correct file ? Is there a standard/proper way to do that ?

If you make the directory names into proper identifiers like v460 and 
v461 and add __init__.py to each to make them packages and have both on 
search path, then

import v460.orb #or import v460.orb as orb460
import v461.orb #or import v460.orb as orb461

will get you both. One way or another, they have to get different names 
within Python.

Terry Jan Reedy



From wilk at flibuste.net  Wed Jul 22 12:45:19 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 16:45:19 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
Message-ID: <4a67421e$0$31038$426a74cc@news.free.fr>

On 22-07-2009, George Sakkis wrote:
> On Jul 22, 7:38?am, William Dode <w... at flibuste.net> wrote:
>
>> I updated the script (python, c and java) with your unrolled version
>> + somes litle thinks.
>>
>> I also tried with python3.1, unladen Q2, ironpython1.1.1
>>
>> Unfortunately it doesn't work more with shedskin, i'll see on the
>> shedskin group...
>>
>> c 1.85s
>> gcj 2.15s
>> java 2.8s
>> python2.5 + psyco 3.1s
>> unladen-2009Q2 145s (2m45)
>> python2.5 254s (4m14s)
>> python3.1 300s (5m)
>> ironpython1.1.1 680s (11m20)
>
> Cool; it would be interesting to see the numbers for Jython and Boo as
> well if it's not too much effort.

I just tried with jython, but oddly it's faster without array.
Thanks to Mark, i could compile to shedskin again.
And add somes little improvements...

c 1.65s
gcj 1.9s
java 2.4s
python2.5 + psyco 2.9s
shedskin 3.4s
unladen-2009Q2 125s (2m05)
Jython 2.2.1 on java1.6.0_12 176s (without array, like shedskin)
Jython 2.2.1 on java1.6.0_12 334s (with array)
python2.5 215s (3m35s)
python3.1 246s (4m06s)
ironpython1.1.1 512 (8m32s)


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From f.orndorffplunkett at gmail.com  Wed Jul 22 12:45:58 2009
From: f.orndorffplunkett at gmail.com (F.O.P.)
Date: Wed, 22 Jul 2009 09:45:58 -0700 (PDT)
Subject: Not understanding this documentation
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
	<mailman.3538.1248275284.8015.python-list@python.org>
Message-ID: <081d1a50-fd7f-4f87-889e-262bc7e2debd@x5g2000prf.googlegroups.com>

On Jul 22, 9:07?am, "Rhodri James" <rho... at wildebst.demon.co.uk>
wrote:
> On Wed, 22 Jul 2009 15:46:09 +0100, F.O.P. <f.orndorffplunk... at gmail.com> ?
> wrote:
>
> >http://bugs.python.org/issue5358
> > I simply installed 3.0 on my ubuntubox brought my project from a
> > windows machine and made necessary changes to what I had used from os
> > and os.path. ?I have an error at the end of this line:
> > for k in range(I):
> > and the error:
> > SyntaxError: invalid character in identifier
>
> > I've already declared I way above as the lenth of an array (I = len
> > (IA))
> > There shouldn't be a problem there aren't any issues with other
> > declarations identical to this.
>
> Could you show us slightly more of your code and the rest of the
> error message, please? ?I have a suspicion that the error actually
> lies in the "necessary changes" you made.
>
> --
> Rhodri James *-* Wildebeest Herder to the Masses

I spoke to a friend about it and he found that I had put in a unicode
"semicolon" rather than ASCII.
I feel silly for asking a question like this but there's really no
harm done in asking.  Thank you for the quick response Rhodri!  Much
appreciated!
Cheers


From tjreedy at udel.edu  Wed Jul 22 12:47:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:47:15 -0400
Subject: Finding all cycles within an undirected graph
In-Reply-To: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
References: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
Message-ID: <h47fqi$tqp$2@ger.gmane.org>

disappearedng wrote:
> Hey everyone,
> I am interested to find out all the cycles within an undirected graph.

I think you have to qualify that as 'minimal cycles' to have a 
well-defined problem.



From http  Wed Jul 22 12:55:51 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 09:55:51 -0700
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com>
	<123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com>
Message-ID: <7xws60u06g.fsf@ruckus.brouhaha.com>

Phillip B Oldham <phillip.oldham at gmail.com> writes:
> Implementations like BashReduce <http://blog.last.fm/2009/04/06/
> mapreduce-bash-script> are perfect for such scenarios. I'm simply
> wondering if there's another simpler/smaller implementation of
> MapReduce that plays nicely with Python but doesn't require the setup/
> knowledge overhead of more "robust" implementations such as hadoop and
> disco... maybe similar to Ruby's Skynet.

I usually just spew ssh tasks across whatever computing nodes I can
get my hands on.  It's less organized than something like mapreduce,
but I tend to run one-off tasks that I have to keep an eye on anyway.
I've done stuff like that across up to 100 or so machines and I think
it wouldn't be really worse if the number were a few times higher.  I
don't think it would scale to really large (10,000's of nodes) clusters.


From tjreedy at udel.edu  Wed Jul 22 12:59:01 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:59:01 -0400
Subject: Not understanding this documentation
In-Reply-To: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
Message-ID: <h47ggl$tn$1@ger.gmane.org>

F.O.P. wrote:

Your subject line should have been  about "SyntaxError message"

> http://bugs.python.org/issue5358

Why reference this? Unless you added zero-width joiners in the move, 
this is irrelevant noise.

> I simply installed 3.0 on my ubuntubox

Upgrade to 3.1 as soon as you can. Works better.

> brought my project from a
> windows machine and made necessary changes to what I had used from os
> and os.path.  I have an error at the end of this line:
> for k in range(I):
> and the error:
> SyntaxError: invalid character in identifier
> 
> I've already declared I way above as the lenth of an array (I = len
> (IA))
> There shouldn't be a problem there aren't any issues with other
> declarations identical to this.

I otherwise concur with R. James as there is no syntax error posted.
To make sure there is nothing invisible in that line, do
print(repr("for k in range(I):")) # should be no escaped chars and
print(len("for k in range(I):")) # should be 18, I believe

tjr



From pavlovevidence at gmail.com  Wed Jul 22 13:01:31 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 10:01:31 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
Message-ID: <4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>

On Jul 22, 9:36?am, Ron Garret <rNOSPA... at flownet.com> wrote:
> In article <uRr9m.6558$ze1.5... at news-server.bigpond.net.au>,
> ?Neil Hodgson <nyamatongwe+thun... at gmail.com> wrote:
>
> > milanj:
>
> > > and all of them use native threads (python still use green threads ?)
>
> > ? ?Python uses native threads.
>
> But then it adds the global interpreter lock, which completely
> undermines the utility of native threads. ?So yes, it uses native
> threads, but it does not actually realize the benefits of that use.

Wrong.  It only partially undermines the utility of native threads,
not completely.  Native threading allows some threads to run while
others are blocked in a system call (as well as in a few other minor
cases), which can't be done with green threads.


Carl Banks


From lie.1296 at gmail.com  Wed Jul 22 13:19:02 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 23 Jul 2009 03:19:02 +1000
Subject: Documentation Problems
In-Reply-To: <b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>
References: <h46rpv$lm5$1@adenine.netfront.net>	<mailman.3518.1248261276.8015.python-list@python.org>
	<b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>
Message-ID: <h47hm9$577$1@ger.gmane.org>

Inky 788 wrote:
> On Jul 22, 7:15 am, Tim Golden <m... at timgolden.me.uk> wrote:
>> Mark du Preez wrote:
>>> Hi
>>> Can anyone tell me where to go to suggest changes to the Python
>>> documentation?
>> Drop an entry in the tracker:
>>
>>  http://bugs.python.org
>>
>> Patches are always welcome,
> 
> Could you please provide brief instructions on exactly how to go about
> creating a suitable patch file? I mean, starting from the beginning
> (as in, "check out code from {here} using {this command}", "cd to
> {this} directory", "edit the file in place", "run {this} command to
> create a patch file"). Or perhaps this procedure is already outlined
> elsewhere?

It's the typical svn-based development, "svn checkout" from the
repository (see list of svn urls here:
http://www.python.org/dev/faq/#how-do-i-get-a-checkout-of-the-repository-read-only-and-read-write),
modify the files, then "svn diff" (or "diff -u")

And last but not least, check out the dev-faq:
http://www.python.org/dev/faq/



From http  Wed Jul 22 13:20:20 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 10:20:20 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
Message-ID: <7xskgobpnv.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> Wrong.  It only partially undermines the utility of native threads,
> not completely.  Native threading allows some threads to run while
> others are blocked in a system call (as well as in a few other minor
> cases), which can't be done with green threads.

Why is that such an advantage?  Green threads work fine if you just
organize the i/o system to never block.  


From king.seth at gmail.com  Wed Jul 22 13:32:51 2009
From: king.seth at gmail.com (Seth)
Date: Wed, 22 Jul 2009 10:32:51 -0700 (PDT)
Subject: Pyserial and pyQt
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
	<h45inh$ofk$1@get-news01.get.basefarm.net>
Message-ID: <70e4ebae-908f-4f3a-a96a-6fa0a7a7887a@y19g2000yqy.googlegroups.com>

On Jul 21, 7:24?pm, David Boddie <da... at boddie.org.uk> wrote:
> On Tuesday 21 July 2009 21:37, Seth wrote:
>
> > I have used pyserial in the past but this is my first experience with
> > pyQt. ?I am using the Python xy package for windows current but might
> > move to linux. ?I have a small device that is outputting a basic text
> > string. ?I want to be able to read this string(from the comm port) and
> > update a text box and eventually a graph in pyQt. ?I can't find any
> > documentation or tutorials on how to do this. ?If anyone can point me
> > in the right direction or give me some tips I would be grateful.
>
> It seems that someone has already asked a similar question on Stack
> Overflow, though perhaps you should start with a simpler solution
> and look at more advanced ones later:
>
> ?http://stackoverflow.com/questions/771988/pyqt4-and-pyserial
>
> One starting point is this list of tutorials on the PyQt and PyKDE Wiki:
>
> ?http://www.diotavelli.net/PyQtWiki/Tutorials
>
> Later, when you want to draw graphs, you might find PyQwt useful:
>
> ?http://pyqwt.sourceforge.net/
>
> You may already be aware that there's also a mailing list for PyQt and
> PyKDE:
>
> ?http://www.riverbankcomputing.com/pipermail/pyqt/
>
> Another way to get answers to questions is to join the #pyqt IRC channel
> at freenode.net:
>
> ? irc://irc.freenode.net/
>
> David


Thanks for the response.  I have gone through a lot of the tutorials.
All of them(that I saw) seem to just deal will event-based
applications ie calculator, image viewer, etc.  How do I run pyserial
in the background and pass the information to PyQT and refresh the
screen?  Is there a way to have pyserial run in another thread and
pass the information to the UI?

Thanks,
Seth


From lie.1296 at gmail.com  Wed Jul 22 13:43:14 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 23 Jul 2009 03:43:14 +1000
Subject: How to document Python code properly for Pydoc
In-Reply-To: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>
References: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>
Message-ID: <h47j3k$9gj$1@ger.gmane.org>

jorma kala wrote:
> Hi,
> Do you know where I can find the rules for documenting Python code, so
> that automatic document generation with Pydoc makes the most of the
> comments inserted in the code?
> I know about documenting class and method through triple quote just
> under the class definition. But how do you comment a specific field or
> variable, or how do you document function arguments so that they are
> extracted like in javadoc?
> Thanks very much

pydoc is a simple tool, and doesn't do much. You write in freeform,
although generally you'll do something like this:

def myfunc(a, b):
    '''
    short description of myfunc

    longer description of myfunc, if necessary, and typically includes
    description of the arguments and the behaviors. Also includes the
    description of the return value.
    '''

    pass

pydoc doesn't recognize any special markups. If you want to get more
from the docstring, you need other documentation generator such as
epydoc, Doxygen, or Sphinx.



From phillip.oldham at gmail.com  Wed Jul 22 13:51:17 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Wed, 22 Jul 2009 10:51:17 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com> 
	<123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com> 
	<7xws60u06g.fsf@ruckus.brouhaha.com>
Message-ID: <83889f6f-1e40-435e-b947-af17964e90af@d32g2000yqh.googlegroups.com>

On Jul 22, 5:55?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Phillip B Oldham <phillip.old... at gmail.com> writes:
> I usually just spew ssh tasks across whatever computing nodes I can
> get my hands on. ?It's less organized than something like mapreduce,
> but I tend to run one-off tasks that I have to keep an eye on anyway.

I'm thinking of repeated tasks; things you run regularly, but don't
need to be blisteringly fast. I'll more than likely use Disco, but if
I were to find something more light-weight I'd take a serious look.



From wilk at flibuste.net  Wed Jul 22 13:55:34 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 17:55:34 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
	<4a67421e$0$31038$426a74cc@news.free.fr>
Message-ID: <4a675296$0$1549$426a74cc@news.free.fr>

On 22-07-2009, William Dode wrote:

> c 1.65s
> gcj 1.9s
> java 2.4s
> python2.5 + psyco 2.9s
> shedskin 3.4s

with -bw i have 2.6s

> unladen-2009Q2 125s (2m05)
> Jython 2.2.1 on java1.6.0_12 176s (without array, like shedskin)
> Jython 2.2.1 on java1.6.0_12 334s (with array)
> python2.5 215s (3m35s)
> python3.1 246s (4m06s)
> ironpython1.1.1 512 (8m32s)

somebody can test with ironpython on windows ?

Anyway, it's very impressive. I wonder if unladen will be so close in 
the futur.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From pavlovevidence at gmail.com  Wed Jul 22 13:59:50 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 10:59:50 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
Message-ID: <5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>

On Jul 22, 10:20?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > Wrong. ?It only partially undermines the utility of native threads,
> > not completely. ?Native threading allows some threads to run while
> > others are blocked in a system call (as well as in a few other minor
> > cases), which can't be done with green threads.
>
> Why is that such an advantage? ?Green threads work fine if you just
> organize the i/o system to never block. ?

Because then I don't have to organize the I/O system never to block.


Carl Banks


From davidj411 at gmail.com  Wed Jul 22 14:04:36 2009
From: davidj411 at gmail.com (davidj411)
Date: Wed, 22 Jul 2009 11:04:36 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com> 
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com> 
	<16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com>
Message-ID: <524a57a9-ba45-459b-b62d-81f527888a4e@j19g2000vbp.googlegroups.com>

i never heard of the logging module, but this function seemed simple
enough.

i assume this link is what you refering to:
http://docs.python.org/library/logging.html

thanks for the helpful info. i think "Piet van Oostrum" has resolved
my issue. good eyes!


From dangets at gmail.com  Wed Jul 22 14:15:55 2009
From: dangets at gmail.com (DG)
Date: Wed, 22 Jul 2009 11:15:55 -0700 (PDT)
Subject: list of 'magic methods' or builtin class methods... want to exclude 
	those from dir output
Message-ID: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>

There is probably a better way to do this (please enlighten me, if you
know), but what I want to do is get a list of a class' attributes
minus whatever the 'builtin' methods are.  I would also like to do
this for instances of classes as well.  I don't want to use __dict__
because I want to get all of the attributes that have been added
throughout the inheritance tree, just not the builtin ones.

I was wondering if there is a function to return a list of these, so I
could perform a 'dir' on the object (class or instance) and filter out
the builtin attributes.  I know I could create my own list something
like
['__class__', '__delattr__', ..., '__weakref__'] and use that.  I
would see this being fragile to Python version differences as new ones
are added or taken away.

A more flexible way is to have the list be filled out dynamically by
creating a 'junk' class that inherits only from object and storing
it's dir() output into the filter list.  This is probably what I'll do
unless someone knows of a builtin function that will give me a
(version-safe) list.

Thanks!


From dangets at gmail.com  Wed Jul 22 14:24:21 2009
From: dangets at gmail.com (DG)
Date: Wed, 22 Jul 2009 11:24:21 -0700 (PDT)
Subject: list of 'magic methods' or builtin class methods... want to 
	exclude those from dir output
References: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
Message-ID: <d0773262-53e8-4b48-a931-0c16ad64a034@a39g2000pre.googlegroups.com>

On Jul 22, 12:15?pm, DG <dang... at gmail.com> wrote:
> There is probably a better way to do this (please enlighten me, if you
> know), but what I want to do is get a list of a class' attributes
> minus whatever the 'builtin' methods are. ?I would also like to do
> this for instances of classes as well. ?I don't want to use __dict__
> because I want to get all of the attributes that have been added
> throughout the inheritance tree, just not the builtin ones.
>
> I was wondering if there is a function to return a list of these, so I
> could perform a 'dir' on the object (class or instance) and filter out
> the builtin attributes. ?I know I could create my own list something
> like
> ['__class__', '__delattr__', ..., '__weakref__'] and use that. ?I
> would see this being fragile to Python version differences as new ones
> are added or taken away.
>
> A more flexible way is to have the list be filled out dynamically by
> creating a 'junk' class that inherits only from object and storing
> it's dir() output into the filter list. ?This is probably what I'll do
> unless someone knows of a builtin function that will give me a
> (version-safe) list.
>
> Thanks!

Haha, replying to my own post.  Here is the implementation of my idea
of dynamically creating the filter lists from a 'junk' object.  As of
now it appears that the dir output of a class is the same as the dir
output of an instance, but if that ever changes, this should future
proof it.  This is only a 4-liner, so it is probably good enough for
what I want to do, but I would rather use a builtin/standard way if
there is one.

class A(object):
    pass
class_filter_methods = dir(A)
instance_filter_methods = dir(A())



From dangets at gmail.com  Wed Jul 22 14:28:58 2009
From: dangets at gmail.com (DG)
Date: Wed, 22 Jul 2009 11:28:58 -0700 (PDT)
Subject: list of 'magic methods' or builtin class methods... want to 
	exclude those from dir output
References: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
	<d0773262-53e8-4b48-a931-0c16ad64a034@a39g2000pre.googlegroups.com>
Message-ID: <48e4e3e1-7356-451e-845b-46516ead98b7@v37g2000prg.googlegroups.com>

On Jul 22, 12:24?pm, DG <dang... at gmail.com> wrote:
> On Jul 22, 12:15?pm, DG <dang... at gmail.com> wrote:
>
>
>
> > There is probably a better way to do this (please enlighten me, if you
> > know), but what I want to do is get a list of a class' attributes
> > minus whatever the 'builtin' methods are. ?I would also like to do
> > this for instances of classes as well. ?I don't want to use __dict__
> > because I want to get all of the attributes that have been added
> > throughout the inheritance tree, just not the builtin ones.
>
> > I was wondering if there is a function to return a list of these, so I
> > could perform a 'dir' on the object (class or instance) and filter out
> > the builtin attributes. ?I know I could create my own list something
> > like
> > ['__class__', '__delattr__', ..., '__weakref__'] and use that. ?I
> > would see this being fragile to Python version differences as new ones
> > are added or taken away.
>
> > A more flexible way is to have the list be filled out dynamically by
> > creating a 'junk' class that inherits only from object and storing
> > it's dir() output into the filter list. ?This is probably what I'll do
> > unless someone knows of a builtin function that will give me a
> > (version-safe) list.
>
> > Thanks!
>
> Haha, replying to my own post. ?Here is the implementation of my idea
> of dynamically creating the filter lists from a 'junk' object. ?As of
> now it appears that the dir output of a class is the same as the dir
> output of an instance, but if that ever changes, this should future
> proof it. ?This is only a 4-liner, so it is probably good enough for
> what I want to do, but I would rather use a builtin/standard way if
> there is one.
>
> class A(object):
> ? ? pass
> class_filter_methods = dir(A)
> instance_filter_methods = dir(A())

Wow, I'm a quick one. Sharp as a marble.  2-liner:

class_filter_methods = dir(object)
instance_filter_methods = dir(object())


From invalid at invalid  Wed Jul 22 14:49:58 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 22 Jul 2009 13:49:58 -0500
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
Message-ID: <P_ydnTKt2r_LwvrXnZ2dnUVZ_uSdnZ2d@posted.visi>

On 2009-07-22, Ron Garret <rNOSPAMon at flownet.com> wrote:
> In article <uRr9m.6558$ze1.5162 at news-server.bigpond.net.au>,
>  Neil Hodgson <nyamatongwe+thunder at gmail.com> wrote:
>
>> milanj:
>> 
>> > and all of them use native threads (python still use green threads ?)
>> 
>>    Python uses native threads.
>
> But then it adds the global interpreter lock, which completely 
> undermines the utility of native threads.  So yes, it uses native 
> threads, but it does not actually realize the benefits of that use.

Not all of the time. For library/extension calls that release
the GIL, it does.

-- 
Grant Edwards                   grante             Yow! I was making donuts
                                  at               and now I'm on a bus!
                               visi.com            


From http  Wed Jul 22 15:04:07 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 12:04:07 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
Message-ID: <7xfxco35g8.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> > Why is that such an advantage? ?Green threads work fine if you just
> > organize the i/o system to never block. ?
> 
> Because then I don't have to organize the I/O system never to block.

We're talking about what a language implementation does behind the
scenes, I thought.


From ethan at stoneleaf.us  Wed Jul 22 15:21:04 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 22 Jul 2009 12:21:04 -0700
Subject: Einstein summation notation
In-Reply-To: <7xprbybnso.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<kmr2uu.d1t@spenarnc.xs4all.nl>	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>	<02701951$0$5185$c3e8da3@news.astraweb.com>	<7xljmnahlj.fsf@ruckus.brouhaha.com>	<02706d8f$0$5185$c3e8da3@news.astraweb.com>	<7xab33s8ik.fsf@ruckus.brouhaha.com>	<mailman.3290.1247847474.8015.python-list@python.org>
	<7xprbybnso.fsf@ruckus.brouhaha.com>
Message-ID: <4A6766A0.4000809@stoneleaf.us>

Paul Rubin wrote:
> Ethan Furman <ethan at stoneleaf.us> writes:
> 
>>Or if any(p for p in [header, body, footer, whatever, ...])
> 
> 
> No need for the genexp:
> 
>    if any([header, body, footer, whatever, ...])
> 
> But, you are using the built-in bool cast either way.

Right you are -- and

   if any([header, body, footer, whatever, ...])

sure looks nicer to me than your original code of

   if any(p != '' for p in [header, body, footer, otherthing1, ...])


But there a are a lot of decisions and factors to writing these things 
one way or the other.  I'm just glad Python supports the Something vs. 
Nothing model.

~Ethan~


From tjreedy at udel.edu  Wed Jul 22 15:24:19 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 15:24:19 -0400
Subject: list of 'magic methods' or builtin class methods... want to
	exclude those from dir output
In-Reply-To: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
References: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
Message-ID: <h47p12$rf7$1@ger.gmane.org>

DG wrote:
> There is probably a better way to do this (please enlighten me, if you
> know), but what I want to do is get a list of a class' attributes
> minus whatever the 'builtin' methods are.  I would also like to do
> this for instances of classes as well.  I don't want to use __dict__
> because I want to get all of the attributes that have been added
> throughout the inheritance tree, just not the builtin ones.
> 
> I was wondering if there is a function to return a list of these, so I
> could perform a 'dir' on the object (class or instance) and filter out
> the builtin attributes.  I know I could create my own list something
> like
> ['__class__', '__delattr__', ..., '__weakref__'] and use that.  I
> would see this being fragile to Python version differences as new ones
> are added or taken away.
> 
> A more flexible way is to have the list be filled out dynamically by
> creating a 'junk' class that inherits only from object and storing
> it's dir() output into the filter list.  This is probably what I'll do
> unless someone knows of a builtin function that will give me a
> (version-safe) list.
> 
> Thanks!
3.1
 >>> list(filter(lambda s: s[0:2]!='__', dir(object)))
[]

Now substitute your object for lambda. This assumes of course that you 
are doing no name-mangling __xxx names.

tjr




From pavlovevidence at gmail.com  Wed Jul 22 15:35:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 12:35:52 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
Message-ID: <f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>

On Jul 22, 12:04?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > > Why is that such an advantage? ?Green threads work fine if you just
> > > organize the i/o system to never block. ?
>
> > Because then I don't have to organize the I/O system never to block.
>
> We're talking about what a language implementation does behind the
> scenes, I thought.

No we're not, we are talking about the whether GIL completely or only
partially undermines the use of native threads on Python.

I don't think your fantasy async-only all-green-thread langauge
implementation is possible anyway.  How would you wait on a pipe in
one thread, a socket in another, a semaphore in a third?  (Are there
any popular OSes that offer a unified polling interface to all
possible synchronizations?)  And what do you do about drivers or
libraries that make underlying blocking calls?  What if you have a
busy calculation going on in the background?


Carl Banks


From robert.kern at gmail.com  Wed Jul 22 15:45:41 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 22 Jul 2009 14:45:41 -0500
Subject: clean way prepend an element to a numpy array
In-Reply-To: <7cnr5tF28183hU1@mid.individual.net>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
	<7cnr5tF28183hU1@mid.individual.net>
Message-ID: <h47q96$158$1@ger.gmane.org>

On 2009-07-22 01:51, greg wrote:
> bdb112 wrote:
>
>> I saw this interest syntax on this site
>> x[:0]=0
>>
>> I guess that is cute, but could be confusing....(and doesn't work)
>
> It does if you use an array of the appropriate
> type on the right hand side:
>
> a[:0] = array('i', [0])

Not when 'a' is a numpy array rather than an array.array.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From torriem at gmail.com  Wed Jul 22 16:26:04 2009
From: torriem at gmail.com (Michael Torrie)
Date: Wed, 22 Jul 2009 14:26:04 -0600
Subject: GTK+ ques
In-Reply-To: <1e61b3260907220415g6edb24sb7fe07c83fe346c8@mail.gmail.com>
References: <1e61b3260907220415g6edb24sb7fe07c83fe346c8@mail.gmail.com>
Message-ID: <4A6775DC.1050003@gmail.com>

nipun batra wrote:
> I need to develop a GUI preferably in GTK using c or PYGTK.I have little
> idea about Python.
> Following are requiremnts of the application:
> should be GUI
> Sould be real time
> Should interface serial port
> should display moving maps,like google earth
> It is basically for Ground control station of a UAV.
> How would Python+Pygtk combo work?
> is python slower than c/c++ ,if then by how much?
> any suggestions for the applcation?

All of these things can be done in Python.  Using nice math libraries
like numpy, math-specific things can be very fast.  Whether python is
fast enough only you could say.  PyGTK is nice, but doesn't have
built-in primitives for doing super high level things like moving maps.
 But there are libraries out there that can do this, one of which is
call libchamplain.  A blog post about it is here:

http://blog.pierlux.com/2009/01/10/libchamplain-and-libchamplain-gtk-028-released/en/

libchamplain does have python bindings I think.


From george.sakkis at gmail.com  Wed Jul 22 16:27:13 2009
From: george.sakkis at gmail.com (George Sakkis)
Date: Wed, 22 Jul 2009 13:27:13 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
	<4a67421e$0$31038$426a74cc@news.free.fr>
Message-ID: <36aeca4d-0609-4da2-83a4-376c88869667@p23g2000vbl.googlegroups.com>

On Jul 22, 12:45?pm, William Dode <w... at flibuste.net> wrote:
> On 22-07-2009, George Sakkis wrote:
>
>
>
> > On Jul 22, 7:38?am, William Dode <w... at flibuste.net> wrote:
>
> >> I updated the script (python, c and java) with your unrolled version
> >> + somes litle thinks.
>
> >> I also tried with python3.1, unladen Q2, ironpython1.1.1
>
> >> Unfortunately it doesn't work more with shedskin, i'll see on the
> >> shedskin group...
>
> >> c 1.85s
> >> gcj 2.15s
> >> java 2.8s
> >> python2.5 + psyco 3.1s
> >> unladen-2009Q2 145s (2m45)
> >> python2.5 254s (4m14s)
> >> python3.1 300s (5m)
> >> ironpython1.1.1 680s (11m20)
>
> > Cool; it would be interesting to see the numbers for Jython and Boo as
> > well if it's not too much effort.
>
> I just tried with jython, but oddly it's faster without array.

FYI Jython 2.5 was released last month, you may want to try this
instead of 2.2.

George


From scriptlearner at gmail.com  Wed Jul 22 16:51:18 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Wed, 22 Jul 2009 13:51:18 -0700 (PDT)
Subject: logging outgoing HTTP POST message and incoming response message
Message-ID: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>

I am sending a HTTP POST by using the following codes:

opener = urllib2.build_opener(proxyHandler, MultipartPostHandler)
params = { "audio" : "http://sample.com/my.wav",
"data" : open(file, "rb") }
print opener.open(myURL, params).read()

How do I log or print out the actual POST message (including headers)
that is sent out?
How do I log or print out the response headers as well?

Thanks


From exarkun at divmod.com  Wed Jul 22 16:53:17 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Wed, 22 Jul 2009 16:53:17 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
Message-ID: <20090722205317.2543.659910647.divmod.quotient.4286@henry.divmod.com>

On Wed, 22 Jul 2009 12:35:52 -0700 (PDT), Carl Banks <pavlovevidence at gmail.com> wrote:
>On Jul 22, 12:04?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>> Carl Banks <pavlovevide... at gmail.com> writes:
>> > > Why is that such an advantage? ?Green threads work fine if you just
>> > > organize the i/o system to never block.
>>
>> > Because then I don't have to organize the I/O system never to block.
>>
>> We're talking about what a language implementation does behind the
>> scenes, I thought.
>
>No we're not, we are talking about the whether GIL completely or only
>partially undermines the use of native threads on Python.
>
>I don't think your fantasy async-only all-green-thread langauge
>implementation is possible anyway.  How would you wait on a pipe in
>one thread, a socket in another, a semaphore in a third?  (Are there
>any popular OSes that offer a unified polling interface to all
>possible synchronizations?)

Every OS I can think of can support the three examples you gave here.

>And what do you do about drivers or
>libraries that make underlying blocking calls?

Certainly a point to consider.

>What if you have a busy calculation going on in the background?

What if you do?  Are you suggesting this would somehow prevent I/O from
being serviced?  I'm not sure why, as long as the implementation pays
attention to I/O events.

Jean-Paul


From deets at nospam.web.de  Wed Jul 22 16:54:02 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 22 Jul 2009 22:54:02 +0200
Subject: logging outgoing HTTP POST message and incoming response message
In-Reply-To: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
References: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
Message-ID: <7cpcjaF2915u5U1@mid.uni-berlin.de>

scriptlearner at gmail.com schrieb:
> I am sending a HTTP POST by using the following codes:
> 
> opener = urllib2.build_opener(proxyHandler, MultipartPostHandler)
> params = { "audio" : "http://sample.com/my.wav",
> "data" : open(file, "rb") }
> print opener.open(myURL, params).read()
> 
> How do I log or print out the actual POST message (including headers)
> that is sent out?
> How do I log or print out the response headers as well?

You can use proxy-tools such as tcpmon or sniff traffic using wireshark.

Diez


From scriptlearner at gmail.com  Wed Jul 22 17:18:37 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Wed, 22 Jul 2009 14:18:37 -0700 (PDT)
Subject: logging outgoing HTTP POST message and incoming response message
References: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
	<7cpcjaF2915u5U1@mid.uni-berlin.de>
Message-ID: <0b403bd0-759f-49b6-9eac-3d585d877fe3@k13g2000prh.googlegroups.com>

On Jul 22, 1:54?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> You can use proxy-tools such as tcpmon or sniff traffic using wireshark.
>
> Diez

Thanks,
but I am trying to enable some debug mode to log all outgoing and
incoming messages for certain period of time, and running another
proxy-tool is not very ideal.  It would be great to log it in some log
file.


From piet at cs.uu.nl  Wed Jul 22 17:24:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 23:24:34 +0200
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
	<16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com>
	<524a57a9-ba45-459b-b62d-81f527888a4e@j19g2000vbp.googlegroups.com>
Message-ID: <m2k520l8bx.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:

>d> i never heard of the logging module, but this function seemed simple
>d> enough.

>d> i assume this link is what you refering to:
>d> http://docs.python.org/library/logging.html

>d> thanks for the helpful info. i think "Piet van Oostrum" has resolved
>d> my issue. good eyes!

Without glasses I wouldn't have noticed it :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul 22 17:50:03 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 23:50:03 +0200
Subject: Issue combining gzip and subprocess
References: <mailman.3472.1248192725.8015.python-list@python.org>
	<m2eisam153.fsf@cs.uu.nl>
	<2YednUGQxvntgfrXnZ2dnUVZ_hWdnZ2d@pdx.net>
Message-ID: <m2fxcol75g.fsf@cs.uu.nl>

>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) schreef:

>SDD> Piet van Oostrum wrote:
>>> ...
>>> f = gzip.open(filename, 'w')
>>> proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
>>> while True:
>>> line = proc.stdout.readline()
>>> if not line: break
>>> f.write(line)
>>> f.close()

>SDD> Or even:
>SDD>     proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
>SDD>     with gzip.open(filename, 'w') as dest:
>SDD>         for line in iter(proc.stdout, ''):
>SDD>             f.write(line)

If it would work.

1) with gzip... is not supported in Python < 3.1
2) for line in iter(proc.stdout), i.e. no second argument.
3) dest <==> f should be the same identifier.

Lesson: if you post code either: 
- test it and copy verbatim from your test, or
- write a disclaimer 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul 22 18:17:12 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 00:17:12 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
References: <mailman.3540.1248276934.8015.python-list@python.org>
Message-ID: <m2bpncl5w7.fsf@cs.uu.nl>

>>>>> Krishnakant <hackingkk at gmail.com> (K) wrote:

>K> hello all,
>K> This is a real challenge and I don't know if a solution even exists for
>K> this or not.

>K> I am writing an application which I run as my usual user on ubuntu.
>K> the usernake is let's say kk and it has sudo permission (meaning the
>K> user is in the sudoers list ).


>K> now when i do python myscript.py, the script has to change to another
>K> non-privileged user for some tasks.
>K> let's say for example switch to the postgres user which is dedicated for
>K> postgres and has no other privileges.

>K> I have tryed doing os.setuid(112) where 112 could be the uid of the user
>K> I want the script to swith over.

>K> but I got opperation not permitted.

Being a sudoer is not a privilege to issue the os.setuid system call. It
is only a permission to use the sudo command.

>K> I tryed using subprocess but that did not help me either.  I tryed sudo
>K> su into the Popen command but it throws me into the terminal (shell)
>K> with postgres as the user.

You could execute the command:
sudo -u postgres required_command
with subprocess.

You have another problem then: your password must be supplied unless the
NOPASSWD flag is set in the sudoers file.

>K> But that's now my desired result.
>K> what I exactly want is that the script now continues to execute under
>K> postgres user till the end.

I don't think that's possible if you start as the user kk. 

>K> I don't know how to achieve this iffect.

>K> Infact I will need this during a serious deployment because i would have
>K> my application run as a demon as a dedicated user.

>K> I am finding some code for deamonising a python application but don't
>K> know how to tell the script to change user.

>K> happy hacking.
>K> Krishnakant.



-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From pavlovevidence at gmail.com  Wed Jul 22 18:17:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 15:17:52 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
Message-ID: <64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>

On Jul 22, 1:53?pm, Jean-Paul Calderone <exar... at divmod.com> wrote:
> On Wed, 22 Jul 2009 12:35:52 -0700 (PDT), Carl Banks <pavlovevide... at gmail.com> wrote:
> >On Jul 22, 12:04?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> >> Carl Banks <pavlovevide... at gmail.com> writes:
> >> > > Why is that such an advantage? ?Green threads work fine if you just
> >> > > organize the i/o system to never block.
>
> >> > Because then I don't have to organize the I/O system never to block.
>
> >> We're talking about what a language implementation does behind the
> >> scenes, I thought.
>
> >No we're not, we are talking about the whether GIL completely or only
> >partially undermines the use of native threads on Python.
>
> >I don't think your fantasy async-only all-green-thread langauge
> >implementation is possible anyway. ?How would you wait on a pipe in
> >one thread, a socket in another, a semaphore in a third? ?(Are there
> >any popular OSes that offer a unified polling interface to all
> >possible synchronizations?)
>
> Every OS I can think of can support the three examples you gave here.

I guess you would know, but polling on all of these at once has got
use more obscure calls than I'm familiar with.

On Linux I can use select to wait for pipes and sockets, but not SysV
semaphores AFAIK.  On Windows it's well known that select only works
for sockets.

So do all these OSes have some kind of __mega_unifying_poll system
call that works for anything that might possibly block, that you can
exploit from a user process?


> >And what do you do about drivers or
> >libraries that make underlying blocking calls?
>
> Certainly a point to consider.
>
> >What if you have a busy calculation going on in the background?
>
> What if you do? ?Are you suggesting this would somehow prevent I/O from
> being serviced? ?I'm not sure why, as long as the implementation pays
> attention to I/O events.

Using native theads with blocking allows one to run a background
calculation without burdening it to yield often enough to provide
sufficient response times for other operations (which may or may not
be convenient to do).

Even if it's possible to accomplish arbitrary background processing
without native threading (and it is not, because the background
calculations could be performed by a library you don't control whose
author didn't bother yielding at any point), you cannot reasonably
claim native threads have no advantage in this case.


Carl Banks


From ethan at stoneleaf.us  Wed Jul 22 18:35:01 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 22 Jul 2009 15:35:01 -0700
Subject: Changing the private variables content
In-Reply-To: <4A671BAF.1060204@gmail.com>
References: <mailman.13388.1248268320.8014.python-list@python.org>
	<4A671BAF.1060204@gmail.com>
Message-ID: <4A679415.90407@stoneleaf.us>

Ryniek90 wrote:
>>
>> Got it:
>>
>> exec('self.' + attr + '=\'' + val + '\'')
>>
>> That worked. I think it'll do what you want now ;)
>>
>> Ching-Yun "Xavier" Ho, Technical Artist
>>
>> Contact Information
>> Mobile: (+61) 04 3335 4748
>> Skype ID: SpaXe85
>> Email: contact at xavierho.com <mailto:contact at xavierho.com>
>> Website: http://xavierho.com/
> 
> 
> To bad, that didn't worked in my class. Still the same error:
> "
>  >>> mod.print_module('socket')
> 
> Traceback (most recent call last):
>  File "<pyshell#121>", line 1, in <module>
>    mod.print_module('socket')
>  File "<pyshell#118>", line 51, in print_module
>    module_open = open(self._this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> :-/
> 
>> What is the point of the _SetVar method?
>>
>> Instead of:
>>
>>     self._SetVar(self._this_module, os.path.join(root, f))
>>
>> just do:
>>
>>     self._this_module = os.path.join(root, f)
>>
>> (unless I'm misunderstanding what you're trying to do!)
>>
> 
> Of course i;ve tried, but still get the same error:
> 
> "
>  >>> mod.print_module('socket')
> 
> Traceback (most recent call last):
>  File "<pyshell#121>", line 1, in <module>
>    mod.print_module('socket')
>  File "<pyshell#118>", line 51, in print_module
>    module_open = open(self.this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> It looks like private variable have specific naure, that prevent from 
> traditional editing them.
> Still searching for some tuts about private methods and variables.

No.  There is nothing special about variables with a leading underscore.

_number

is treated by Python *exactly* the same as

number

.  The specific problem in your code above is your _SetVar function, 
among the more general problem of not yet having a good understanding of 
classes in Python.  Keep studying, Python is an awesome language.

I was able to make this work -- hope it helps.

8<-----------------------------------------------------------------------
import os
import sys

class ModPrint(object):
     u"""This will be the doc."""
     def __init__(self):
         self._default_search_path = sys.exec_prefix

     def _search_for_module(self, chosen_module, search_path):
         for root, dirs, files in os.walk(search_path):
             for f in files:
                 if f == ("%s.py" % chosen_module):
                     return os.path.join(root, f)

     def print_module(self, chosen_module, user_search_path=''):
         search_path = user_search_path or self._default_search_path
         module = self._search_for_module(chosen_module, search_path)
         if module is not None:
             module_open = open(module, 'rb')
             module_text = module_open.read()
             module_open.close()
             return module_text
         return 'Module not found...'
8<-----------------------------------------------------------------------


From pinkeen at gmail.com  Wed Jul 22 18:43:08 2009
From: pinkeen at gmail.com (Filip)
Date: Wed, 22 Jul 2009 15:43:08 -0700 (PDT)
Subject: python fast HTML data extraction library
Message-ID: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>

Hello,

Sometime ago I was searching for a library that would simplify mass
data scraping/extraction from webpages. Python XPath implementation
seemed like the way to go. The problem was that most of the HTML on
the net doesn't conform to XML standards, even the XHTML (those
advertised as valid XHTML too) pages.

I tried to fix that with BeautifulSoup + regexp filtering of some
particular cases I encountered. That was slow and after running my
data scraper for some time a lot of new problems (exceptions from
xpath parser) were showing up. Not to mention that BeautifulSoup
stripped almost all of the content from some heavily broken pages
(50+KiB page stripped down to some few hundred bytes). Character
encoding conversion was a hell too - even UTF-8 pages had some non-
standard characters causing issues.


Cutting to the chase - that's when I decided to take the matter into
my own hands. I hacked together a solution sporting completely new
approach overnight. It's called htxpath - a small, lightweight (also
without dependencies) python library which lets you to extract
specific tag(s) from a HTML document using a path string which has
very similar syntax to xpath (but is more convenient in some cases).
It did a very good job for me.

My library, rather than parsing the whole input into a tree, processes
it like a char stream with regular expressions.

I decided to share it with everyone so there it is: http://code.google.com/p/htxpath/
I am aware that it is not beautifully coded as my experience with
python is rather brief, but I am curious if it will be useful to
anyone (also it's my first potentially [real-world ;)] useful project
gone public). In that case I promise to continue developing it. It's
probably full of bugs, but I can't catch them all by myself.

regards,
Filip Sobalski


From ben+python at benfinney.id.au  Wed Jul 22 19:26:37 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 23 Jul 2009 09:26:37 +1000
Subject: Documentation Problems
References: <h46rpv$lm5$1@adenine.netfront.net>
	<mailman.3518.1248261276.8015.python-list@python.org>
	<b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>
Message-ID: <87ocrc7102.fsf@benfinney.id.au>

Inky 788 <inky788 at gmail.com> writes:

> Could you please provide brief instructions on exactly how to go about
> creating a suitable patch file? I mean, starting from the beginning
> (as in, "check out code from {here} using {this command}", "cd to
> {this} directory", "edit the file in place", "run {this} command to
> create a patch file"). Or perhaps this procedure is already outlined
> elsewhere?

Yes. The documentation is built from source documents under version
control, like the rest of Python. So the procedure for creating and
submitting patches is the same, and is covered by the Developer's FAQ
<URL:http://www.python.org/dev/faq/>.

-- 
 \           ?If you ever fall off the Sears Tower, just go real limp, |
  `\     because maybe you'll look like a dummy and people will try to |
_o__)                catch you because, hey, free dummy.? ?Jack Handey |
Ben Finney


From piet at cs.uu.nl  Wed Jul 22 19:34:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 01:34:34 +0200
Subject: Changing the private variables content
References: <mailman.13388.1248268320.8014.python-list@python.org>
	<mailman.3534.1248271304.8015.python-list@python.org>
Message-ID: <m27hy0l2b9.fsf@cs.uu.nl>

>>>>> Ryniek90 <ryniek90 at gmail.com> (R) wrote:

>R> It looks like private variable have specific naure, that prevent from
>R> traditional editing them.
>R> Still searching for some tuts about private methods and variables.

Why do you stubbornly keep saying that, while you have been told that it
is not the case. Instead you would do better debugging your own case
instead of making false claims. Sprinkle a few print statements in your
code to see what is happening.

Here are a few thing for you to look at:

       #using private method '_search_for_module' with 'self.' prefix
       #to search for prefered module
       self._search_for_module(_chosen_module, _user_search_path)

You call it with 2 parameters: _chosen_module, _user_search_path
Look at the definition:

   def _search_for_module(self, *args):

It has *args to pick up the arguments, but they are not used in the
body. Instead you use self._user_search_path and self._chosen_module.
The latter one is always '', never changed to anything else. So it is
not surprising that the module is not found.
 
In print_module you have the same kind of confusion.

Do you think that magically self._chosen_module gets the value of
_chosen_module? Is that you idea of `private variables'?

Or do you think that *args does magical things?

       """Private method which walks through default Python
       installation directories, and search for prefered module."""
           #walking thru all directories available in path _user_search_path'
       for root, dirs, files in os.walk(self._user_search_path):
           for f in files:
               #if found file 'f' is THAT module,
               #full path to THAT file is assigned to variable
               print "Trying %s" % f
               if f == ("%s.py" % self._chosen_module):
                   self._this_module = os.path.join(root, f)


-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul 22 19:36:38 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 01:36:38 +0200
Subject: Python-list Digest, Vol 70, Issue 282
References: <mailman.13395.1248271304.8014.python-list@python.org>
	<mailman.3544.1248279076.8015.python-list@python.org>
Message-ID: <m23a8ol27t.fsf@cs.uu.nl>

>>>>> Ryniek90 <ryniek90 at gmail.com> (R) wrote:

>R> "
>R> Didn't worked, so i wil reuse your class, and modify it later. Now i see
>R> that working on private objects complex.

No it's not complex. *You* make it complex.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From Brian.Mingus at colorado.edu  Wed Jul 22 19:51:52 2009
From: Brian.Mingus at colorado.edu (Brian)
Date: Wed, 22 Jul 2009 17:51:52 -0600
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
In-Reply-To: <4a675296$0$1549$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
	<4a67421e$0$31038$426a74cc@news.free.fr>
	<4a675296$0$1549$426a74cc@news.free.fr>
Message-ID: <9839a05c0907221651o6afaa80xc25f37ff9bcbeea5@mail.gmail.com>

On Wed, Jul 22, 2009 at 11:55 AM, William Dode <wilk at flibuste.net> wrote:

> On 22-07-2009, William Dode wrote:
>
> > c 1.65s
> > gcj 1.9s
> > java 2.4s
> > python2.5 + psyco 2.9s
> > shedskin 3.4s
>
> with -bw i have 2.6s
>
> > unladen-2009Q2 125s (2m05)
> > Jython 2.2.1 on java1.6.0_12 176s (without array, like shedskin)
> > Jython 2.2.1 on java1.6.0_12 334s (with array)
> > python2.5 215s (3m35s)
> > python3.1 246s (4m06s)
> > ironpython1.1.1 512 (8m32s)
>
> somebody can test with ironpython on windows ?
>
> Anyway, it's very impressive. I wonder if unladen will be so close in
> the futur.
>
> --
> William Dod? - http://flibuste.net
> Informaticien Ind?pendant
>

I had time to run a few tests. Since psyco doesn't work on 64 bit and the
developer now works on pypy I used that.

Intel Core i7 920 @ 2.66GHz
Kubuntu Jaunty Jackal

c gcc    4.3.3 0.77s
gcj      4.3.3 0.81s
java     1.6   0.99s
shedskin       1.63s
jython   2.2.1 85.37s
cpython  2.6.2 93.26s
pypy     1.1.0 1612.15s

 <http://mail.python.org/mailman/listinfo/python-list>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/3d82420a/attachment.html>

From gagsl-py2 at yahoo.com.ar  Wed Jul 22 19:52:06 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 20:52:06 -0300
Subject: Detect target name in descriptor __set__ method
References: <mailman.3504.1248238988.8015.python-list@python.org>
	<3cb5f960-16f7-4fc6-841f-d0706f0e1d0a@s31g2000yqs.googlegroups.com>
Message-ID: <op.uxhtw4x8x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 05:31:13 -0300, Jon Clements <joncle at googlemail.com>  
escribi?:
> On 22 July, 06:02, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:

>> I have a class attribute 'foo' which is a data descriptor. I create an ?
>> instance of such class. When I say instance.foo = value, the descriptor  
>> ?
>> __set__ method is called. Is there any way to obtain the name being ?
>> assigned to? ('foo' in this example). That is, I want to know the  
>> target ?
>> name for the assignment that triggered the __set__ method call.

>>>> class Test:
> 	def __setattr__(self, what, value):
> 		print what, value
>
>
>>>> t = Test()
>>>> t.foo = 'x'
> foo x
>
> Is that what you're after?

Yes and no. __setattr__ has a terrible overhead as it is invoked for each  
and every attribute being set, special or not. Using a custom descriptor  
seems better, because it allows to intercept just the desired attribute.  
If only I had access to the name being used...

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Wed Jul 22 20:05:55 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 21:05:55 -0300
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst>
Message-ID: <op.uxhuj5olx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James  
<rhodri at wildebst.demon.co.uk> escribi?:
> On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina  
> <gagsl-py2 at yahoo.com.ar> wrote:
>
>
>> class X(object):
>>    foo = descriptor()
>>
>> x = X()
>> x.foo = "value"
>
> Isn't this going to create a brand new instance attribute x.foo that has  
> nothing to do with the descriptor anyway?

No, it's up to the descriptor __set__ method what happens in this case.  
Think of the standard 'property' descriptor, the fset function can do  
whatever it wants.
Also, a data descriptor takes precedence over any instance attribute of  
the same name that might exist.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Wed Jul 22 20:10:54 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 21:10:54 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com>
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
	<EgE9m.507$646.499@nwrddc01.gnilink.net>
Message-ID: <op.uxhusgo9x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 10:14:12 -0300, Alan G Isaac <alan.isaac at gmail.com>  
escribi?:

>>>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>>>> def apply2(itr, methodname, *args, **kwargs):
>>>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>>>     for item in itr:
>>>>>         f(item)
>
>
>>> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>>>> for obj in objects:
>>>>     getattr(obj, methodname)(*args, **kwargs)
>
>
>> En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac:
>>> Are there any obvious considerations in choosing
>>> between those two?
>
>
> On 7/20/2009 3:29 AM Gabriel Genellina apparently wrote:
>> The operator.methodcaller version is faster in my tests for large
>> collections, but slightly slower when you have very few elements.
>
>
> So it seems.  Is this easily explained?

NLMPI

-- 
Gabriel Genellina



From martin.hellwig at dcuktec.org  Wed Jul 22 20:22:14 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 23 Jul 2009 01:22:14 +0100
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <mailman.3540.1248276934.8015.python-list@python.org>
References: <mailman.3540.1248276934.8015.python-list@python.org>
Message-ID: <Y7GdnVBIVrqqMPrXnZ2dnUVZ8gWdnZ2d@bt.com>

Krishnakant wrote:
<cut elevate/dropdown rights problem>

I've seen a method before in a MS cmd script (MakeMeAdmin.cmd) for the 
purpose of temporarily elevating your rights but remaining the same user.

There was a need trick in that the script checks itself on what 
credentials it runs, if it is not the appropriate one it will call 
itself again with runas (about the same as sudo) and exits.

If it has the right credentials it will perform the actual task.

That might be a way to solve your problem.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From http  Wed Jul 22 20:27:23 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 17:27:23 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
Message-ID: <7xws60p7kk.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> I don't think your fantasy async-only all-green-thread langauge
> implementation is possible anyway. 

Erlang and GHC both work like that, quite successfully:

  http://shootout.alioth.debian.org/gp4/benchmark.php?test=threadring&lang=all

> How would you wait on a pipe in one thread, a socket in another, a
> semaphore in a third?  

You can select on pipes and sockets, I think.  Not sure about
semaphores.  

> (Are there any popular OSes that offer a unified polling interface to
> all possible synchronizations?)  And what do you do about drivers or
> libraries that make underlying blocking calls?  What if you have a
> busy calculation going on in the background?

I don't think the concept of "drivers" applies to user-mode programs.
For FFI calls you would use an OS thread.  The language runtime
switches between busy computation threads on a timer tick.


From wells at submute.net  Wed Jul 22 20:40:11 2009
From: wells at submute.net (Wells Oliver)
Date: Wed, 22 Jul 2009 19:40:11 -0500
Subject: RPY2 examples?
Message-ID: <3f1a902d0907221740i62487600xc2210ca9fede5791@mail.gmail.com>

I am trying to find examples using RPY2 to render R graphs to PNG/PDF/etc.
The only things I can find use rpy 1.x. Any references? Thanks!

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/56bfd645/attachment.html>

From kwmsmith at gmail.com  Wed Jul 22 21:25:17 2009
From: kwmsmith at gmail.com (Kurt Smith)
Date: Wed, 22 Jul 2009 21:25:17 -0400
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
In-Reply-To: <861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
	<861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
Message-ID: <c266a7930907221825y4c1c4a26g1549e7308355b9dc@mail.gmail.com>

On Wed, Jul 22, 2009 at 2:48 AM, Bearophile<bearophileHUGS at lycos.com> wrote:
> greg:
>> Posting benchmark times for Pyrex or Cython is pretty
>> meaningless without showing the exact code that was
>> used, since times can vary enormously depending on
>> how much you C-ify things.
>
> Was this link, shown by William, not enough?
> http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1

I took a stab at converting the recent psyco-optimized code to cython,
and got a speedup.

gcj    4.3.3    1.39s
gcc    4.3.3    1.55s
cython 11.2     1.91s
psyco           1.94s
javac  1.5.0_19 2.00s
python 2.5.4    168.37s

It was just a matter of cdef-ing all the arrays & integers --
bearophile already did the hard work :-)

Here's the cython code; all the others are from the repo.

#################################################
DEF NMOVES = 8
DEF SIDE = 5
DEF SQR_SIDE = SIDE * SIDE

cdef int circuit[SQR_SIDE]
cdef int nsolutions = 0

cdef int movex[NMOVES]
cdef int movey[NMOVES]
py_movex = [-1,-2,-2,-1,+1,+2,+2,+1]
py_movey = [-2,-1,+1,+2,+2,+1,-1,-2]
for i in range(NMOVES):
   movex[i] = py_movex[i]
   movey[i] = py_movey[i]
shift = [x * SIDE + y for x,y in zip(py_movex, py_movey)]
cdef int shift_0 = shift[0]
cdef int shift_1 = shift[1]
cdef int shift_2 = shift[2]
cdef int shift_3 = shift[3]
cdef int shift_4 = shift[4]
cdef int shift_5 = shift[5]
cdef int shift_6 = shift[6]
cdef int shift_7 = shift[7]

def showCircuit():
   print
   for x in xrange(SIDE):
       x_SIDE = x * SIDE
       for y in xrange(SIDE):
           if SQR_SIDE < 100:
               print "%02d " % circuit[x_SIDE + y],
           else:
               print "%03d " % circuit[x_SIDE + y],
       print

cdef void solve(int nb, int x, int y,
       int SIDE=SIDE, int SQR_SIDE=SQR_SIDE, int *circuit=circuit,
       int shift_0=shift_0,
       int shift_1=shift_1,
       int shift_2=shift_2,
       int shift_3=shift_3,
       int shift_4=shift_4,
       int shift_5=shift_5,
       int shift_6=shift_6,
       int shift_7=shift_7,
       ):
   global nsolutions

   cdef int newx, newy
   cdef int pos = x * SIDE + y
   circuit[pos] = nb
   if nb == SQR_SIDE:
       #showCircuit()
       nsolutions += 1
       circuit[pos] = 0
       return

   newx = x + -1
   if newx >= 0 and newx < SIDE:
       newy = y + -2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_0]:
           solve(nb+1, newx, newy)

   newx = x + -2
   if newx >= 0 and newx < SIDE:
       newy = y + -1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_1]:
           solve(nb+1, newx, newy)

   newx = x + -2
   if newx >= 0 and newx < SIDE:
       newy = y + 1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_2]:
           solve(nb+1, newx, newy)

   newx = x + -1
   if newx >= 0 and newx < SIDE:
       newy = y + 2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_3]:
           solve(nb+1, newx, newy)

   newx = x + 1
   if newx >= 0 and newx < SIDE:
       newy = y + 2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_4]:
           solve(nb+1, newx, newy)

   newx = x + 2
   if newx >= 0 and newx < SIDE:
       newy = y + 1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_5]:
           solve(nb+1, newx, newy)

   newx = x + 2
   if newx >= 0 and newx < SIDE:
       newy = y + -1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_6]:
           solve(nb+1, newx, newy)

   newx = x + 1
   if newx >= 0 and newx < SIDE:
       newy = y + -2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_7]:
           solve(nb+1, newx, newy)

   circuit[pos] = 0

def main():
   print "Search for side=%d" % SIDE
   cdef int x,y
   for x in range(SIDE):
       for y in range(SIDE):
           solve(1, x, y);
   print "\n%dx%d case, %d solutions." % (SIDE, SIDE, nsolutions)

def run():
   import time
   s=time.time()
   main()
   print time.time()-s
#################################################


From scriptlearner at gmail.com  Wed Jul 22 21:45:45 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Wed, 22 Jul 2009 18:45:45 -0700 (PDT)
Subject: regex: multiple matching for one string
Message-ID: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>

For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
will like to take out the values (valuea, valueb, and valuec).  How do
I do that in Python?  The group method will only return the matched
part.  Thanks.

p = re.compile('#a=*;b=*;c=*;')
m = p.match(line)
        if m:
             print m.group(),


From ptmcg at austin.rr.com  Wed Jul 22 21:53:33 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Wed, 22 Jul 2009 18:53:33 -0700 (PDT)
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
Message-ID: <88e8ea19-7106-406a-a531-88c2b6893987@y7g2000yqa.googlegroups.com>

On Jul 22, 5:43?pm, Filip <pink... at gmail.com> wrote:
>
> My library, rather than parsing the whole input into a tree, processes
> it like a char stream with regular expressions.
>

Filip -

In general, parsing HTML with re's is fraught with easily-overlooked
deviations from the norm.  But since you have stepped up to the task,
here are some comments on your re's:

# You should use raw string literals throughout, as in:
# blah_re = re.compile(r'sljdflsflds')
# (note the leading r before the string literal).  raw string
literals
# really help keep your re expressions clean, so that you don't ever
# have to double up any '\' characters.

# Attributes might be enclosed in single quotes, or not enclosed in
any quotes at all.
attr_re = re.compile('([\da-z]+?)\s*=\s*\"(.*?)\"', re.DOTALL |
re.UNICODE | re.IGNORECASE)

# Needs re.IGNORECASE, and can have tag attributes, such as <BR
CLEAR="ALL">
line_break_re = re.compile('<br\/?>', re.UNICODE)

# what about HTML entities defined using hex syntax, such as &#xxxx;
amp_re = re.compile('\&(?![a-z]+?\;)', re.UNICODE | re.IGNORECASE)

How would you extract data from a table?  For instance, how would you
extract the data entries from the table at this URL:
http://tf.nist.gov/tf-cgi/servers.cgi ?  This would be a good example
snippet for your module documentation.

Try extracting all of the <a href=...>sldjlsfjd</a> links from
yahoo.com, and see how much of what you expect actually gets matched.

Good luck!

-- Paul


From rurpy at yahoo.com  Wed Jul 22 22:00:42 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Wed, 22 Jul 2009 19:00:42 -0700 (PDT)
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
Message-ID: <a7445b44-6518-4180-afe0-d20a246ce161@h18g2000yqj.googlegroups.com>

On Jul 22, 7:45 pm, "scriptlear... at gmail.com"
<scriptlear... at gmail.com> wrote:
> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
> will like to take out the values (valuea, valueb, and valuec).  How do
> I do that in Python?  The group method will only return the matched
> part.  Thanks.
>
> p = re.compile('#a=*;b=*;c=*;')
> m = p.match(line)
>         if m:
>              print m.group(),

p = re.compile('#a=([^;]*);b=([^;]*);c=([^;]*);')
m = p.match(line)
if m:
    print m.group(1),m.group(2),m.group(3),

Note that "=*;" in your regex will match
zero or more "=" characters -- probably not
what you intended.

"[^;]* will match any string up to the next
";" character which will be a value (assuming
you don't have or care about embedded whitespace.)

You might also want to consider using a r'...'
string for the regex, which will make including
backslash characters easier if you need them
at some future time.


From wuwei23 at gmail.com  Wed Jul 22 22:04:34 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 22 Jul 2009 19:04:34 -0700 (PDT)
Subject: Ideas for problem with chat server application!
References: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
Message-ID: <40c22282-7526-4064-8885-62a87107bb3d@p10g2000prm.googlegroups.com>

On Jul 22, 6:27?pm, "David Adamo Jr." <dtgead... at yahoo.com> wrote:
> Suggestions are highly appreciated.

I haven't used it but I've heard good things about FireDaemon, which
can run any script or program as a Windows service.

Apparently the Lite version is free:
http://www.download-freeware-shareware.com/Freeware-System-Utilities.php?Type=14387

Hope this helps.



From cindy at speed-voip.com  Wed Jul 22 22:36:31 2009
From: cindy at speed-voip.com (cindy)
Date: Wed, 22 Jul 2009 22:36:31 -0400
Subject: [Unblocking VoIP in UAE] for freedom!
Message-ID: <e044bbf877a62d09a89e8b12438141c0@localhost.localdomain>

Please view this newsletter online at:
http://www.mynewsletterbuilder.com/tools/view_newsletter.php?newsletter_id=1409985533
SpeedVoIP Communication Technology Co., LTD. - 600, 6th Avenue S.W. - Calgary
- Alberta - T2P 0S5

Subscribe to this newsletter:
https://www.mynewsletterbuilder.com/tools/subscription.php?username=svsales&send_id=712043215&l=s&newsletter_id=1409985533
Unsubscribe python-list at python.org:
https://www.mynewsletterbuilder.com/tools/subscription.php?username=svsales&send_id=712043215&l=u&email=python-list at python.org
Change your preferences:
https://www.mynewsletterbuilder.com/tools/subscription.php?username=svsales&send_id=712043215&l=p&email=python-list at python.org
Forward to a friend:
http://www.mynewsletterbuilder.com/tools/forward.php?username=svsales&newsletter_id=1409985533&email=python-list at python.org&send_id=712043215
Report this email as spam:
https://www.mynewsletterbuilder.com/tools/abuse_report.php?username=svsales&send_id=712043215&email=python-list at python.org

This email was sent using MyNewsletterBuilder.com.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/0cc8e817/attachment.html>

From songofacandy at gmail.com  Wed Jul 22 23:06:56 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Wed, 22 Jul 2009 20:06:56 -0700 (PDT)
Subject: What is file.encoding convention?
Message-ID: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>

In document <http://docs.python.org/library/
stdtypes.html#file.encoding>:

>> The encoding that this file uses. When Unicode strings are written to a file,
>>  they will be converted to byte strings using this encoding. In addition,
>> when the file is connected to a terminal, the attribute gives the encoding
>> that the terminal is likely to use

But in logging.StreamHandler.emit() ::

                try:
                    if (isinstance(msg, unicode) and
                        getattr(stream, 'encoding', None)):
                        #fs = fs.decode(stream.encoding)
                        try:
                            stream.write(fs % msg)
                        except UnicodeEncodeError:
                            #Printing to terminals sometimes fails.
For example,
                            #with an encoding of 'cp1251', the above
write will
                            #work if written to a stream opened or
wrapped by
                            #the codecs module, but fail when writing
to a
                            #terminal even when the codepage is set to
cp1251.
                            #An extra encoding step seems to be
needed.
                            stream.write((fs % msg).encode
(stream.encoding))
                    else:
                        stream.write(fs % msg)
                except UnicodeError:
                    stream.write(fs % msg.encode("UTF-8"))

And behavior of sys.stdout in Windows::
>>> import sys
>>> sys.stdout.encoding
'cp932'
>>> u = u"???"
>>> u
u'\u3042\u3044\u3046'
>>> print >>sys.stdout, u
???
>>> sys.stderr.write(u)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode characters in position
0-2: ordinal not in range(128)


What is file.encoding convention?
If I want to write a unicode string to a file(-like) that have
encoding attribute, I should do
(1) try: file.write(unicode_str),
(2) except UnicodeEncodeError: file.write(unicode_str.encode
(file.encoding))
like logging?
It seems agly.


From sjmachin at lexicon.net  Wed Jul 22 23:24:47 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 22 Jul 2009 20:24:47 -0700 (PDT)
Subject: Not understanding this documentation
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
	<mailman.3538.1248275284.8015.python-list@python.org>
	<081d1a50-fd7f-4f87-889e-262bc7e2debd@x5g2000prf.googlegroups.com>
Message-ID: <c20222ea-6258-403b-b2fa-707df898aff7@d4g2000prc.googlegroups.com>

On Jul 23, 2:45?am, "F.O.P." <f.orndorffplunk... at gmail.com> wrote:
> On Jul 22, 9:07?am, "Rhodri James" <rho... at wildebst.demon.co.uk>
> wrote:
>
>
>
>
>
>
>
> > On Wed, 22 Jul 2009 15:46:09 +0100, F.O.P. <f.orndorffplunk... at gmail.com> ?
> > wrote:
>
> > >http://bugs.python.org/issue5358
> > > I simply installed 3.0 on my ubuntubox brought my project from a
> > > windows machine and made necessary changes to what I had used from os
> > > and os.path. ?I have an error at the end of this line:
> > > for k in range(I):
> > > and the error:
> > > SyntaxError: invalid character in identifier
>
> > > I've already declared I way above as the lenth of an array (I = len
> > > (IA))
> > > There shouldn't be a problem there aren't any issues with other
> > > declarations identical to this.
>
> > Could you show us slightly more of your code and the rest of the
> > error message, please? ?I have a suspicion that the error actually
> > lies in the "necessary changes" you made.
>
> > --
> > Rhodri James *-* Wildebeest Herder to the Masses
>
> I spoke to a friend about it and he found that I had put in a unicode
> "semicolon" rather than ASCII.

This is rather puzzling. What are you describing as a "unicode
semicolon"? Possibilities include:

(a) U+003B SEMICOLON (which is exactly what you need)
(b) U+037E GREEK QUESTION MARK (which looks like (a))
(c) U+061B ARABIC SEMICOLON (which looks like (a) rotated 180 degrees)

How did you get it into your source file?

What was in your
# coding: ?????
or similar line at the top of your source file?


From aahz at pythoncraft.com  Wed Jul 22 23:38:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 22 Jul 2009 20:38:30 -0700
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com>
Message-ID: <h48lvm$qau$1@panix3.panix.com>

In article <f3d88edf-b5d3-43e4-89a3-b05ef0f55b47 at p28g2000vbn.googlegroups.com>,
Carl Banks  <pavlovevidence at gmail.com> wrote:
>
>You have to be REALLY REALLY careful not to pass any user-supplied
>data to it if this is a server running on your computer, of course.

Unless, of course, your users are paying for this service.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From aahz at pythoncraft.com  Wed Jul 22 23:54:11 2009
From: aahz at pythoncraft.com (Aahz)
Date: 22 Jul 2009 20:54:11 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<mailman.3433.1248109750.8015.python-list@python.org>
	<h4312f$307$1@panix3.panix.com>
	<mailman.3451.1248139114.8015.python-list@python.org>
Message-ID: <h48mt3$9f5$1@panix3.panix.com>

In article <mailman.3451.1248139114.8015.python-list at python.org>,
D'Arcy J.M. Cain <darcy at druid.net> wrote:
>On 20 Jul 2009 17:10:55 -0700
>aahz at pythoncraft.com (Aahz) wrote:
>>>I understand what you want but I can't see how a toolkit can do that.
>>>How do you program "graceful?"  It seems pretty application specific.
>> 
>> Presumably the JS toolkit generates both code and HTML.  Actions that
>> normally get executed by JS should degrade to plain HTML links and form
>> submits (or possibly not display at all if it's a pure convenience).
>
>As I said, I do understand what you are after but I still think it is a
>judgement call.  What defines "convenience?"  How does the library know
>what is essential and what is pretty?

Presumably a JS toolkit designed for this purpose would have an API to
specify the handling of such issues.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From aahz at pythoncraft.com  Wed Jul 22 23:55:20 2009
From: aahz at pythoncraft.com (Aahz)
Date: 22 Jul 2009 20:55:20 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application 
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
	<1c994086-8c58-488f-b3b3-6161c4b2ba05@k30g2000yqf.googlegroups.com>
Message-ID: <h48mv8$39n$1@panix3.panix.com>

In article <1c994086-8c58-488f-b3b3-6161c4b2ba05 at k30g2000yqf.googlegroups.com>,
Paul Boddie  <paul at boddie.org.uk> wrote:
>On 20 Jul, 18:00, a... at pythoncraft.com (Aahz) wrote:
>>
>> Out of curiosity, are there any JavaScript toolkits that generate code
>> that degrades gracefully when JavaScript is disabled?
>
>You mean "Web toolkits which use JavaScript", I presume. I have
>written (and use myself) a toolkit/framework called XSLForms (part of
>the XSLTools distribution) which supports in-page updates (AJAX,
>effectively) that degrade to vanilla whole-page requests if JavaScript
>is switched off:
>
>http://www.boddie.org.uk/python/XSLTools.html

Thanks!  I'll take a look after OSCON.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From gagsl-py2 at yahoo.com.ar  Thu Jul 23 00:27:12 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 23 Jul 2009 01:27:12 -0300
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <op.uxh3ollxx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 11:36:51 -0300, Inky 788 <inky788 at gmail.com> escribi?:
> On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
> wrote:

>> The good reason is the immutability, which lets you use
>> a tuple as a dict key. ?
>
> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

Many people posted useful examples of tuples as dictionary keys in this
thread. Just to add another one (emulate SQL GROUP BY):

ope_by_dept = defaultdict(int)
total_times = defaultdict(float)

for dept_name, ope_name, ope_date, engineer in list_of_operations:
     ope_by_dept[dept_name, ope_start.month] += 1
     total_times[dept_name, engineer] += ope_end - ope_start

print "Operations per department per month"
for dept_name, month in sorted(ope_by_dept):
      print dept_name, month, ope_by_dept[dept_name, month]

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul 23 00:27:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 23 Jul 2009 01:27:15 -0300
Subject: logging outgoing HTTP POST message and incoming response message
References: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
	<7cpcjaF2915u5U1@mid.uni-berlin.de>
	<0b403bd0-759f-49b6-9eac-3d585d877fe3@k13g2000prh.googlegroups.com>
Message-ID: <op.uxh6hxfbx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 18:18:37 -0300, scriptlearner at gmail.com
<scriptlearner at gmail.com> escribi?:
> On Jul 22, 1:54?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> You can use proxy-tools such as tcpmon or sniff traffic using wireshark.
>
> Thanks,
> but I am trying to enable some debug mode to log all outgoing and
> incoming messages for certain period of time, and running another
> proxy-tool is not very ideal.  It would be great to log it in some log
> file.

You may install a custom HTTPHandler:

class LoggingHTTPConnection(httplib.HTTPConnection):

      def request(self, method, url, body=None, headers={}):
          print method, url, headers
          httplib.HTTPConnection.request(self, method, url, body, headers)

      def getresponse(self):
          response = httplib.HTTPConnection.getresponse(self)
          print response.status, response.msg
          return response

class LoggingHTTPHandler(urllib2.HTTPHandler):
      def http_open(self, req):
          return self.do_open(LoggingHTTPConnection, req)

opener = urllib2.build_opener(LoggingHTTPHandler, ...)

-- 
Gabriel Genellina



From nagle at animats.com  Thu Jul 23 00:40:38 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 22 Jul 2009 21:40:38 -0700
Subject: MySQLdb for Python 3.1 getting close?
Message-ID: <4a67e912$0$1603$742ec2ed@news.sonic.net>

   Is MySQLdb available for Python 3.1 yet?

   http://sourceforge.net/projects/mysql-python/

says the last supported Python version is 2.5.  Any progress in sight?

				John Nagle	


From martin.hellwig at dcuktec.org  Thu Jul 23 02:16:22 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 23 Jul 2009 07:16:22 +0100
Subject: Ideas for problem with chat server application!
In-Reply-To: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
References: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
Message-ID: <LNqdnZxuvdmlnfXXnZ2dnUVZ8vqdnZ2d@bt.com>

David Adamo Jr. wrote:
<cut>
> My
> attempt was to create a windows service that start automatically and
> runs this batch file using a Network Service account on the server
> system. Although, I'm having a hard time with this (temporarily), I
> would love to ask if there are any alternatives to using a windows
> service. Suggestions are highly appreciated.

This is definitely the right way to go, perhaps reviewing a template 
which I use for windows services may help you:
http://blog.dcuktec.com/2009/07/python-windows-service-template.html

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From jayshree06comp at gmail.com  Thu Jul 23 02:37:17 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Wed, 22 Jul 2009 23:37:17 -0700 (PDT)
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
Message-ID: <b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>

On Jul 21, 8:59?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> jayshree <jayshree06c... at gmail.com> (j) wrote:
> >j> M2Crypto package not showing the 'recipient_public_key.pem' file at
> >j> linux terminal .how do i get/connect with recipient public key.
> >j> exactly i need to check how can i open this file through linux
> >j> commands.
> >j> import M2Crypto def encrypt(): recip = M2Crypto.RSA.load_pub_key(open
> >j> ('recipient_public_key.pem','rb').read()) print recip; plaintext =
> >j> whatever i need to encrypt msg = recip.public_encrypt
> >j> (plaintext,RSA.pkcs1_padding) print msg;
> >j> after calling the function its not giving any output and even any
> >j> error
> >j> i also tried as 'Will' said
> >j> pk = open('public_key.pem','rb').read() print pk; rsa =
> >j> M2Crypto.RSA.load_pub_key(pk)
> >j> whats the mistake i am not getting .will somebody help me out.
> >j> is something wrong in opening 'recipient_public_key.pem'. is M2Crypto
> >j> contain this file inbuilt .from where this file taking public key of
> >j> the recipient i'. what this file contain and how it will work .should
> >j> i need to create such a file for my purpose.if it is then how can i
> >j> create this ?and how it will retrieve the key,where i recognize my
> >j> recipient to get his public key .is something like database at server.
> >j> please give me a quick response......
> >j> looking for your answer.
>
> Please:
> 1. Type your python code with newlines and proper indentation.
> 2. Show the error messages that your code gives when you run it.
> 3. Use proper capital letters at the beginning of your sentences.
> 4. Don't fire so many questions in rapid succession.
>
> The recipient_public_key.pem file is the public key of the recipient
> which means the person that is going to receive the encrypted message.
> You should get it from the recipient him/herself or from some key store
> where s/he has deposited it.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org- Hide quoted text -
>
> - Show quoted text -
Here is the code that i used

import M2Crypto
from M2Crypto import RSA

def encrypt():
    recip = M2Crypto.RSA.load_pub_key(open
('recipient_public_key.pem','rb').read())
    #recip = M2Crypto.RSA.load_pub_key('recipient_public_key.pem')
    print recip;
    plaintext =" whatever i need to encrypt"
    msg = recip.public_encrypt(plaintext,RSA.pkcs1_padding)
    print msg;


    encrypt()


error coming like - IOError: [Errno 2] No such file or directory:
'recipient_public_key.pem'

Is this not the inbuilt file.
How should i create such type of file.


From wilk at flibuste.net  Thu Jul 23 02:44:56 2009
From: wilk at flibuste.net (William Dode)
Date: 23 Jul 2009 06:44:56 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
	<861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
	<mailman.3563.1248312318.8015.python-list@python.org>
Message-ID: <4a6806e8$0$22900$426a74cc@news.free.fr>

On 23-07-2009, Kurt Smith wrote:
> On Wed, Jul 22, 2009 at 2:48 AM, Bearophile<bearophileHUGS at lycos.com> wrote:
>> greg:
>>> Posting benchmark times for Pyrex or Cython is pretty
>>> meaningless without showing the exact code that was
>>> used, since times can vary enormously depending on
>>> how much you C-ify things.
>>
>> Was this link, shown by William, not enough?
>> http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1
>
> I took a stab at converting the recent psyco-optimized code to cython,
> and got a speedup.

thanks, i updated my repo with litle more tips.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From amrita at iisermohali.ac.in  Thu Jul 23 03:22:15 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Thu, 23 Jul 2009 12:52:15 +0530 (IST)
Subject: how two join and arrange two files together
Message-ID: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>


Hi,

I have two large files:

FileA
15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C =
21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35
23 ALA H = 8.78	N =  CA =  HA = C = 179.93.................

and

FileB
21 ALA  helix (helix_alpha, helix2)
23 ALA  helix (helix_alpha, helix3)
38 ALA  helix (helix_alpha, helix3)...........

now what i want that i will make another file in which i will join the two
file in such a way that only matching entries will come like here 21 and
23 ALA is in both files, so the output will be something like:-

21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA  helix
(helix_alpha, helix2)
23 ALA H = 8.78	N =  CA =  HA = C = 179.93|23 ALA  helix (helix_alpha,
helix3)

and further i will make another file in which i will be able to put those
lines form this file based on the missing atom value, like for 21 ALA HA
is not defined so i will put it another file based on its HA missing value
similarly i will put 23 ALA on another file based on its missing N,CA and
HA value.

I tried to join the two file based on their matching entries by:---
>>>from collections import defaultdict
>>>
>>> if __name__ == "__main__":
...      a = open("/home/amrita/alachems/chem100.txt")
...      c = open("/home/amrita/secstr/secstr100.txt")
...
>>> def source(stream):
...     return (line.strip() for line in stream)
...
...
>>> def merge(sources):
...     for m in merge([source(a),source(c)]):
...         print "|".join(c.ljust(10) for c in m)
...

but it is not giving any value.






Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From hendrik at microcorp.co.za  Thu Jul 23 03:25:22 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Thu, 23 Jul 2009 09:25:22 +0200
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <200907230925.22747.hendrik@microcorp.co.za>

On Wednesday 22 July 2009 12:03:44 superpollo wrote:

> can i do something like the above, but using a *binary* number? (e.g.
> 00101101 instead of 45) ?

00101101 is not hex 45.
hex 45 is 01000101

>>> chr(int('01000101',2))
'E'
>>>

- Hendrik





From hendrik at microcorp.co.za  Thu Jul 23 03:42:27 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Thu, 23 Jul 2009 09:42:27 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <200907230942.27558.hendrik@microcorp.co.za>

On Wednesday 22 July 2009 16:36:51 Inky 788 wrote:
> On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
>
> wrote:

> > The good reason is the immutability, which lets you use
> > a tuple as a dict key. ?
>
> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

Steven showed why you cannot have a mutable thing
as a key in a dict.

if you think it is contrived, then please consider how you would 
keep track of say the colour of a pixel on a screen at position
(x,y) - this is about the simplest "natural" tuple format and
example.

There are other equally valid examples, as has been pointed
out.  (may have been in another thread - am a bit confused
about that right now)

- Hendrik


From clp2 at rebertia.com  Thu Jul 23 04:16:04 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 23 Jul 2009 01:16:04 -0700
Subject: how two join and arrange two files together
In-Reply-To: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
References: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907230116m67a73918gbd344b9a5289b45@mail.gmail.com>

On Thu, Jul 23, 2009 at 12:22 AM, <amrita at iisermohali.ac.in> wrote:
>
> Hi,
>
> I have two large files:
>
> FileA
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C =
> 21 ALA H = 7.66 N = 123.58 CA = 54.33 HA = C = 179.35
> 23 ALA H = 8.78 N = ?CA = ?HA = C = 179.93.................
>
> and
>
> FileB
> 21 ALA ?helix (helix_alpha, helix2)
> 23 ALA ?helix (helix_alpha, helix3)
> 38 ALA ?helix (helix_alpha, helix3)...........
>
> now what i want that i will make another file in which i will join the two
> file in such a way that only matching entries will come like here 21 and
> 23 ALA is in both files, so the output will be something like:-
>
> 21 ALA H = 7.66 N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA ?helix
> (helix_alpha, helix2)
> 23 ALA H = 8.78 N = ?CA = ?HA = C = 179.93|23 ALA ?helix (helix_alpha,
> helix3)
>
> and further i will make another file in which i will be able to put those
> lines form this file based on the missing atom value, like for 21 ALA HA
> is not defined so i will put it another file based on its HA missing value
> similarly i will put 23 ALA on another file based on its missing N,CA and
> HA value.
>
> I tried to join the two file based on their matching entries by:---
>>>>from collections import defaultdict
>>>>
>>>> if __name__ == "__main__":
> ... ? ? ?a = open("/home/amrita/alachems/chem100.txt")
> ... ? ? ?c = open("/home/amrita/secstr/secstr100.txt")
> ...
>>>> def source(stream):
> ... ? ? return (line.strip() for line in stream)
> ...
> ...
>>>> def merge(sources):
> ... ? ? for m in merge([source(a),source(c)]):
> ... ? ? ? ? print "|".join(c.ljust(10) for c in m)
> ...
>
> but it is not giving any value.

You never actually called any of your <expletive deleted> functions.

Slightly corrected version:

from collections import defaultdict

def source(stream):
    return (line.strip() for line in stream)

def merge(sources):
    for m in sources:
        print "|".join(c.ljust(10) for c in m)

if __name__ == "__main__":
    a = open("/home/amrita/alachems/chem100.txt")
    c = open("/home/amrita/secstr/secstr100.txt")
    merge([source(a), source(c)])


It's still not sophisticated enough to give the exact output you're
looking for, but it is a step in the right direction.

You really should try asking someone from your CS Dept to help you. It
would seriously take a couple hours, at most.

- Chris
-- 
Still brandishing a cluestick a vain...
http://blog.rebertia.com


From pavlovevidence at gmail.com  Thu Jul 23 04:47:03 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 01:47:03 -0700 (PDT)
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org> 
	<f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com> 
	<h48lvm$qau$1@panix3.panix.com>
Message-ID: <20efdb6a-c1a5-47dc-8546-7c4ae548e22d@g1g2000pra.googlegroups.com>

On Jul 22, 8:38?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <f3d88edf-b5d3-43e4-89a3-b05ef0f55... at p28g2000vbn.googlegroups.com>,
> Carl Banks ?<pavlovevide... at gmail.com> wrote:
>
> >You have to be REALLY REALLY careful not to pass any user-supplied
> >data to it if this is a server running on your computer, of course.
>
> Unless, of course, your users are paying for this service.

Well, yes, but I assume that by the time you're deliberately letting
users pay to run their programs on your server, you will already have
deployed a full-blown, multi-tiered security strategy that includes
validation by the server process.  That was sort of beyond the scope
of the OP's question.


Carl Banks


From helvinlui at gmail.com  Thu Jul 23 04:55:51 2009
From: helvinlui at gmail.com (Helvin)
Date: Thu, 23 Jul 2009 01:55:51 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
	<mailman.2902.1247154895.8015.python-list@python.org>
	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>
Message-ID: <16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>

I believe I now have vtkpython.exe. However, my 'import vtk' statement
in my python code is not working. The error says something like "no
module named vtk".
Where do I find modules for vtk in pyqt? Do they exist?

They must, right? Because there are people using vtk in pyqt? Or do I
have to use OpenGL?

Confused...
Helvin


From jjkk73 at gmail.com  Thu Jul 23 05:01:45 2009
From: jjkk73 at gmail.com (jorma kala)
Date: Thu, 23 Jul 2009 10:01:45 +0100
Subject: How to document Python code properly for Pydoc
In-Reply-To: <h47j3k$9gj$1@ger.gmane.org>
References: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>
	<h47j3k$9gj$1@ger.gmane.org>
Message-ID: <bda7ac6d0907230201u11680734i622825a7be34e9af@mail.gmail.com>

Thanks very much for your help

On Wed, Jul 22, 2009 at 6:43 PM, Lie Ryan <lie.1296 at gmail.com> wrote:

>  jorma kala wrote:
> > Hi,
> > Do you know where I can find the rules for documenting Python code, so
> > that automatic document generation with Pydoc makes the most of the
> > comments inserted in the code?
> > I know about documenting class and method through triple quote just
> > under the class definition. But how do you comment a specific field or
> > variable, or how do you document function arguments so that they are
> > extracted like in javadoc?
> > Thanks very much
>
> pydoc is a simple tool, and doesn't do much. You write in freeform,
> although generally you'll do something like this:
>
> def myfunc(a, b):
>    '''
>    short description of myfunc
>
>    longer description of myfunc, if necessary, and typically includes
>    description of the arguments and the behaviors. Also includes the
>    description of the return value.
>    '''
>
>    pass
>
> pydoc doesn't recognize any special markups. If you want to get more
> from the docstring, you need other documentation generator such as
> epydoc, Doxygen, or Sphinx.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/49225759/attachment.html>

From user at example.net  Thu Jul 23 05:04:24 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 11:04:24 +0200
Subject: binary literal
In-Reply-To: <mailman.3566.1248333819.8015.python-list@python.org>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
	<mailman.3566.1248333819.8015.python-list@python.org>
Message-ID: <4a682799$0$28504$4fafbaef@reader2.news.tin.it>

Hendrik van Rooyen wrote:
> On Wednesday 22 July 2009 12:03:44 superpollo wrote:
> 
> 
>>can i do something like the above, but using a *binary* number? (e.g.
>>00101101 instead of 45) ?
> 
> 
> 00101101 is not hex 45.
> hex 45 is 01000101
> 

whoopsie daisie!

> 
>>>>chr(int('01000101',2))
> 
> 'E'
> 

much obliged.

bye


From ryszard.szopa at gmail.com  Thu Jul 23 05:08:39 2009
From: ryszard.szopa at gmail.com (Ryszard Szopa)
Date: Thu, 23 Jul 2009 02:08:39 -0700 (PDT)
Subject: strange error when trying to log something
Message-ID: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>

Hi,

I've recently reinstalled Python 2.6 (from DMG) on my Mac, and I am
running into very strage errors. Namely, logging seems to be badly
broken. When I open the interpreter through Django's manage.py shell
and try to use logging, I get the following error:

>>> logging.critical('ala')
------------------------------------------------------------
Traceback (most recent call last):
  File "<ipython console>", line 1, in <module>
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1416, in critical
    root.critical(*((msg,)+args), **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1074, in critical
    self._log(CRITICAL, msg, args, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1142, in _log
    record = self.makeRecord(self.name, level, fn, lno, msg, args,
exc_info, func, extra)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1117, in makeRecord
    rv = LogRecord(name, level, fn, lno, msg, args, exc_info, func)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 272, in __init__
    from multiprocessing import current_process
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/multiprocessing/__init__.py", line 64, in <module>
    from multiprocessing.util import SUBDEBUG, SUBWARNING
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/multiprocessing/util.py", line 121, in <module>
    _afterfork_registry = weakref.WeakValueDictionary()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/weakref.py", line 51, in __init__
    UserDict.UserDict.__init__(self, *args, **kw)
TypeError: unbound method __init__() must be called with UserDict
instance as first argument (got WeakValueDictionary instance instead)

I was able to silence the error (and be able to work normally) by
making UserDict.UserDict inherit from object.

Any ideas what is causing the error? Before I updated Python
everything was fine. Am I breaking a lot of things by making
UserDict.UserDict a new style class?

Thanks in advance for any insight.

  -- Ryszard Szopa


From songofacandy at gmail.com  Thu Jul 23 05:24:42 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Thu, 23 Jul 2009 02:24:42 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
Message-ID: <697fa41f-9c6a-438f-9c47-9566a79bdf82@p36g2000prn.googlegroups.com>

> What is file.encoding convention?
> If I want to write a unicode string to a file(-like) that have
> encoding attribute, I should do
> (1) try: file.write(unicode_str),
> (2) except UnicodeEncodeError: file.write(unicode_str.encode
> (file.encoding))
> like logging?
> It seems agly.

s/agly/ugly/


From __peter__ at web.de  Thu Jul 23 05:29:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 11:29:13 +0200
Subject: strange error when trying to log something
References: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>
Message-ID: <h49ah5$hv3$02$1@news.t-online.com>

Ryszard Szopa wrote:

> Hi,
> 
> I've recently reinstalled Python 2.6 (from DMG) on my Mac, and I am
> running into very strage errors. Namely, logging seems to be badly
> broken. When I open the interpreter through Django's manage.py shell
> and try to use logging, I get the following error:
> 
>>>> logging.critical('ala')
> ------------------------------------------------------------
> Traceback (most recent call last):
>   File "<ipython console>", line 1, in <module>
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1416, in critical
>     root.critical(*((msg,)+args), **kwargs)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1074, in critical
>     self._log(CRITICAL, msg, args, **kwargs)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1142, in _log
>     record = self.makeRecord(self.name, level, fn, lno, msg, args,
> exc_info, func, extra)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1117, in makeRecord
>     rv = LogRecord(name, level, fn, lno, msg, args, exc_info, func)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 272, in __init__
>     from multiprocessing import current_process
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/multiprocessing/__init__.py", line 64, in <module>
>     from multiprocessing.util import SUBDEBUG, SUBWARNING
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/multiprocessing/util.py", line 121, in <module>
>     _afterfork_registry = weakref.WeakValueDictionary()
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/weakref.py", line 51, in __init__
>     UserDict.UserDict.__init__(self, *args, **kw)
> TypeError: unbound method __init__() must be called with UserDict
> instance as first argument (got WeakValueDictionary instance instead)
> 
> I was able to silence the error (and be able to work normally) by
> making UserDict.UserDict inherit from object.
> 
> Any ideas what is causing the error? Before I updated Python
> everything was fine. Am I breaking a lot of things by making
> UserDict.UserDict a new style class?
> 
> Thanks in advance for any insight.
> 
>   -- Ryszard Szopa

I have a hunch that you are triggering a reload() somewhere. Example:

Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import weakref
>>> weakref.WeakValueDictionary()
<WeakValueDictionary at 140598938447312>
>>> import UserDict
>>> reload(UserDict)
<module 'UserDict' from '/usr/lib/python2.6/UserDict.pyc'>
>>> weakref.WeakValueDictionary()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/weakref.py", line 51, in __init__
    UserDict.UserDict.__init__(self, *args, **kw)
TypeError: unbound method __init__() must be called with UserDict instance 
as first argument (got WeakValueDictionary instance instead)

Try restarting the interpreter after any change to source files.

Peter



From nobody at nowhere.com  Thu Jul 23 05:37:55 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 23 Jul 2009 10:37:55 +0100
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>
Message-ID: <pan.2009.07.23.09.37.54.891000@nowhere.com>

On Wed, 22 Jul 2009 15:17:52 -0700, Carl Banks wrote:

> So do all these OSes have some kind of __mega_unifying_poll system
> call that works for anything that might possibly block, that you can
> exploit from a user process?

Threads ;)

They also have the advantage that one thread can run while another is
waiting on disk I/O, which isn't something which can be done with a
select/poll interface (even if select/poll worked for files, it doesn't
help for mapped files).




From hackingkk at gmail.com  Thu Jul 23 05:50:10 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Thu, 23 Jul 2009 15:20:10 +0530
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <m2bpncl5w7.fsf@cs.uu.nl>
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl>
Message-ID: <1248342610.3698.7.camel@krishna-laptop>

On Thu, 2009-07-23 at 00:17 +0200, Piet van Oostrum wrote:
> Being a sudoer is not a privilege to issue the os.setuid system call. It
> is only a permission to use the sudo command.
> 
Yes, So I would like to know if python can change the user to some other
non-privileged user during the script execution?

> >K> I tryed using subprocess but that did not help me either.  I tryed sudo
> >K> su into the Popen command but it throws me into the terminal (shell)
> >K> with postgres as the user.
> 
> You could execute the command:
> sudo -u postgres required_command
> with subprocess.
> 
Ok, but the problem is much more complex.
What if I want to do the following.
1, change the user for a particular script to the postgres user.
2. now execute the python code for connecting to the postgresql
database.
In the second point I actually want to execute python code not shell
level command so will the sudo -u in the subprocess.Popen change the
user in the script?
In short I would just like to have the script run under another user
let's say postgres as long as a certain action is going on, for example
connecting to the postgresql database.

 
> You have another problem then: your password must be supplied unless the
> NOPASSWD flag is set in the sudoers file.
> 
That is clear, the only problem is that I want the script to run as
postgres user although it was started by the user kk.


happy hacking.
Krishnakant.




From news123 at free.fr  Thu Jul 23 05:56:45 2009
From: news123 at free.fr (News123)
Date: Thu, 23 Jul 2009 11:56:45 +0200
Subject: available formats and params for Image.save()
Message-ID: <4a6833dd$0$22599$426a34cc@news.free.fr>

Hi,

Somehow I have difficulties reading the documentation for PIL (Image)

Is there an easy way to know which formats are supported and what their
names are?

Is there an easy way to know which parameters are supported by
Image.save(). How can I list them where are they documented?


Somehow I consider the documentation to be a little weak on this points.
all the documentation says (at least where I looked) is:

>     class Image
>      |  Methods defined here:
> . . .
>  save(self, fp, format=None, **params)
>      |      Save image to file or stream

In order to find out how the format name for a .jpg file I did following:

import Image
img = Image.open("afile.jpg")
print img.format


Then I saw, that the result was 'JPEG' and not 'JPG' as I tried first

I'm at a complete loss at finding out what parameters the save function
accepts for saving a JPG file or a PNG file

Is there an easy way of finding this in any doc or do I have to dive
into the sources.


If there's no easy way:
Wouldn't a better documentation increase the 'user experience'?



Thanks in advance for any pointers


N





From nobody at nowhere.com  Thu Jul 23 06:03:58 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 23 Jul 2009 11:03:58 +0100
Subject: Multiple versions of python
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
	<mailman.3465.1248186000.8015.python-list@python.org>
Message-ID: <pan.2009.07.23.10.03.58.172000@nowhere.com>

On Tue, 21 Jul 2009 10:19:42 -0400, Dave Angel wrote:

> The other thing you may want to do in a batch file is to change the file 
> associations so that you can run the .py file directly, without typing 
> "python" or "pythonw" in front of it.
> 
> The relevant Windows commands are:     assoc and ftype

However: assoc and ftype modify the registry keys under
HKLM\Software\Classes. This works fine if these are the only relevant
keys, but if you also have settings under HKCU\Software\Classes, those
will take precedence, so assoc and/or ftype won't have any effect.

Also, you typically need at least "Power User" status in order to modify
the keys under HKLM, while any user should be able to modify those under
HKCU (HKCU is a "virtual" key, corresponding to HKU\<interactive user>).



From user at example.net  Thu Jul 23 06:23:13 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 12:23:13 +0200
Subject: raster (PIL)
Message-ID: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>

hi.

i wrote a program which transforms a string of zeroes ando ones into a 
png file.

#!/usr/bin/env python
import Image
import sys
bits_in_a_byte = 8
raster_string = """\
00000000000000000000000000000000
00100100111100100000100000111100
00100100100000100000100000100100
00111100111000100000100000100100
00100100100000100000100000100100
00100100111100111100111100111100
00000000000000000000000000000000
00000000000000000000000000000000
00000000111100100000111100000000
00000000100000100000100100000000
00000000100000100000111100000000
00000000100000100000100000000000
00000000111100111100100000000000
00000000000000000000000000000000
"""
raster_lines = raster_string.splitlines()
high = len(raster_lines)
wide = len(raster_lines[0])
bytes_in_a_row = wide/bits_in_a_byte
bitmap = ""
for raster_line in raster_lines:
     for byte_count in range(bytes_in_a_row):
         first_bit = byte_count*bits_in_a_byte
         bitmap += 
chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] , 2))
im = Image.fromstring("1", (wide , high) , bitmap)
im.save(sys.stdout , "PNG")

any suggestions for improvement?

bye


From digitig at gmail.com  Thu Jul 23 06:28:22 2009
From: digitig at gmail.com (Tim Rowe)
Date: Thu, 23 Jul 2009 11:28:22 +0100
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <aee48b3c0907230328tcd8ed72r4788da787ec0df2c@mail.gmail.com>

2009/7/22 Inky 788 <inky788 at gmail.com>:

> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

If you are used to working in a language that doesn't allow it then
you'll probably carry on using the work-arounds that you have always
used. It almost certainly only seems obscure because you're not
considering it when it would be a natural solution. In a language that
builds *very* heavily on the concept of dictionaries it's not obscure
at all!

-- 
Tim Rowe


From nick at craig-wood.com  Thu Jul 23 07:30:08 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 06:30:08 -0500
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
	<d6f06288-4250-4065-bdf1-a880de3b875a@y7g2000yqa.googlegroups.com>
Message-ID: <slrnh6ggph.6oq.nick@irishsea.home.craig-wood.com>

srepmub <mark.dufour at gmail.com> wrote:
>  please send any program that doesn't work with shedskin (it still is
>  experimental after all) to me, or create an issue at
>  shedskin.googlecode.com, and I will have a look at the problem.

I divided and conquered the program as suggested and eventually I got
it to compile and run correctly :-)

I learnt that if you have lots of variables with indeterminate type
then shedskin takes a very long time indeed before blowing up!

I also learnt that shedskin doesn't support the idiom I'd been using
for creating shallow copies, namely the Board.__new__(Board) below.
shedskin compiles it ok, but the C++ won't compile complaning about
not being able to find __init__ methods

Producing these warnings

*WARNING* rush_hour_solver_cut_down.py:71: class 'Vehicle' has no method '__new__'
*WARNING* rush_hour_solver_cut_down.py:72: variable 'new' has no type
*WARNING* rush_hour_solver_cut_down.py:236: variable 'new_vehicle' has no type

And these compile errors

rush_hour_solver_cut_down.cpp:94: error: ?__new__? is not a member of ?__rush_hour_solver_cut_down__::Vehicle?
rush_hour_solver_cut_down.cpp:95: error: expected type-specifier before ?;? token
rush_hour_solver_cut_down.cpp: In member function ?void* __rush_hour_solver_cut_down__::Board::move(int, int)?:
rush_hour_solver_cut_down.cpp:276: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:276: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:279: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:279: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:281: error: invalid conversion from ?void*? to ?__rush_hour_solver_cut_down__::Vehicle*?


    def copy(self):
        new = Board.__new__(Board)
        new.me_x = self.me_x
        new.me_y = self.me_y
        new.depth = self.depth
        new.parent = self
        new.best_child = None
        new.board = [self.board[i][:] for i in range(WIDTH)]
        new.rep = self.rep[:]
        new.vehicles = self.vehicles[:]
        return new

I changed to using copy.copy which did work, but I couldn't name my
copy methods "copy" otherwise I got this error from the C++ compile

rush_hour_solver_cut_down.cpp: In member function '__rush_hour_solver_cut_down__::Vehicle* __rush_hour_solver_cut_down__::Vehicle::copy()':
rush_hour_solver_cut_down.cpp:94: error: no matching function for call to '__rush_hour_solver_cut_down__::Vehicle::copy(__rush_hour_solver_cut_down__::Vehicle* const)'
rush_hour_solver_cut_down.cpp:89: note: candidates are: __rush_hour_solver_cut_down__::Vehicle* __rush_hour_solver_cut_down__::Vehicle::copy()
rush_hour_solver_cut_down.cpp: In member function '__rush_hour_solver_cut_down__::Board* __rush_hour_solver_cut_down__::Board::copy()':
rush_hour_solver_cut_down.cpp:135: error: no matching function for call to '__rush_hour_solver_cut_down__::Board::copy(__rush_hour_solver_cut_down__::Board* const)'
rush_hour_solver_cut_down.cpp:129: note: candidates are: __rush_hour_solver_cut_down__::Board* __rush_hour_solver_cut_down__::Board::copy()

So I renamed them to pycopy, and they ended up looking like

    def pycopy(self):
        new = copy(self)
        new.parent = self
        new.best_child = None
        new.board = [self.board[i][:] for i in range(WIDTH)]
        new.rep = self.rep[:]
        new.vehicles = self.vehicles[:]
        return new

After all that - some timing results!

Python:   9.3 seconds
Psyco:    5.8 seconds
ShedSkin: 1.0 seconds

Impressive!

I put the code http://www.craig-wood.com/nick/pub/rush_hour_solver_cut_down.py

I left in the commented out bits of code I had to change.

This is only part of the project (375 lines) - it solves Rush Hour
boards.  There is another part which I haven't attempted to compile
yet which finds the most difficult possible boards using a combination
of back tracking and a genetic algorithm.

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From stef.mientki at gmail.com  Thu Jul 23 07:36:54 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 13:36:54 +0200
Subject: sqlite3 performance problems only in python
Message-ID: <4A684B56.3020906@gmail.com>

hello,

until now I used only small / simple databases in Python with sqlite3.
Now I've a large and rather complex database.

The most simple query (with just a result of 100 rows),
takes about 70 seconds.
And all that time is consumed in "cursor.fetchall"

Using the same database in Delphi,
using the same query,
takes less than 5 seconds (including displaying the full table in a grid).

Are there in Python faster ways to get the query results ?
Would it be faster if I used an ODBC coupling and PyODBC to interface 
the database ?

thanks,
Stef Mientki


From deets at nospam.web.de  Thu Jul 23 07:47:45 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 13:47:45 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
Message-ID: <7cr0v1F28dhltU1@mid.uni-berlin.de>

superpollo wrote:

> hi.
> 
> i wrote a program which transforms a string of zeroes ando ones into a
> png file.
> 
> #!/usr/bin/env python
> import Image
> import sys
> bits_in_a_byte = 8
> raster_string = """\
> 00000000000000000000000000000000
> 00100100111100100000100000111100
> 00100100100000100000100000100100
> 00111100111000100000100000100100
> 00100100100000100000100000100100
> 00100100111100111100111100111100
> 00000000000000000000000000000000
> 00000000000000000000000000000000
> 00000000111100100000111100000000
> 00000000100000100000100100000000
> 00000000100000100000111100000000
> 00000000100000100000100000000000
> 00000000111100111100100000000000
> 00000000000000000000000000000000
> """
> raster_lines = raster_string.splitlines()
> high = len(raster_lines)
> wide = len(raster_lines[0])
> bytes_in_a_row = wide/bits_in_a_byte

This will give you the wrong result if not divideable by bits_in_a_byte. 

> bitmap = ""
> for raster_line in raster_lines:
>      for byte_count in range(bytes_in_a_row):
>          first_bit = byte_count*bits_in_a_byte
>          bitmap +=
> chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] , 2))
> im = Image.fromstring("1", (wide , high) , bitmap)
> im.save(sys.stdout , "PNG")
> 
> any suggestions for improvement?

Instead of 

res = ""
for ...:
    res += ...

use 

res = []
for ...:
    res.append(...)

"".join(res)

There are some optimizations for the +=-op on strings, but I'm not sure how
far they go, and the other form is safer.

Diez


From paul at subsignal.org  Thu Jul 23 07:50:47 2009
From: paul at subsignal.org (paul)
Date: Thu, 23 Jul 2009 13:50:47 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <1248342610.3698.7.camel@krishna-laptop>
References: <mailman.3540.1248276934.8015.python-list@python.org>	<m2bpncl5w7.fsf@cs.uu.nl>
	<1248342610.3698.7.camel@krishna-laptop>
Message-ID: <h49ine$cs8$1@ger.gmane.org>

Krishnakant schrieb:
> On Thu, 2009-07-23 at 00:17 +0200, Piet van Oostrum wrote:
>> Being a sudoer is not a privilege to issue the os.setuid system call. It
>> is only a permission to use the sudo command.
>>
> Yes, So I would like to know if python can change the user to some other
> non-privileged user during the script execution?
If the user running python program is allowed to call setuid() then yes.

> 
>>> K> I tryed using subprocess but that did not help me either.  I tryed sudo
>>> K> su into the Popen command but it throws me into the terminal (shell)
>>> K> with postgres as the user.
>> You could execute the command:
>> sudo -u postgres required_command
>> with subprocess.
>>
> Ok, but the problem is much more complex.
No.

> What if I want to do the following.
> 1, change the user for a particular script to the postgres user.
Did you try running "sudo -u postgres blabla" with subprocess?

> 2. now execute the python code for connecting to the postgresql
> database.
> In the second point I actually want to execute python code not shell
> level command so will the sudo -u in the subprocess.Popen change the
> user in the script?
No, as the name "subprocess" suggests you are spawning a new process 
which gets another uid through sudo. This does not affect the parent 
process.

hth
  Paul




From piet at cs.uu.nl  Thu Jul 23 08:06:14 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 14:06:14 +0200
Subject: Copy/paste through LAN
References: <c1e24f0f-b34f-45e8-81bd-118baa1e8632@c29g2000yqd.googlegroups.com>
Message-ID: <m2ws5zk3ih.fsf@cs.uu.nl>

>>>>> Jun <junhufr at gmail.com> (J) wrote:

>J> Hello,
>J> I've a client/server application which uses Pyro to communicate each
>J> other.
>J> Now i try to implement copy/paste through LAN between server
>J> controlled
>J> filesystem to my local windows machine (I could list files in client's
>J> window).
>J> How can i pass the url information through Pyro ?

What do you mean? Do you want to copy a file or copy file names? Copying
a file between two machines can best be done by a specialized protocol,
like HTTP or scp. Pasting a file doesn't make sense IMHO.

And URLs are just strings.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Thu Jul 23 08:23:24 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 14:23:24 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl>
	<mailman.3575.1248342706.8015.python-list@python.org>
Message-ID: <m2skgnk2pv.fsf@cs.uu.nl>

>>>>> Krishnakant <hackingkk at gmail.com> (K) wrote:

>K> On Thu, 2009-07-23 at 00:17 +0200, Piet van Oostrum wrote:
>>> Being a sudoer is not a privilege to issue the os.setuid system call. It
>>> is only a permission to use the sudo command.
>>> 
>K> Yes, So I would like to know if python can change the user to some other
>K> non-privileged user during the script execution?

As I said you can't (unless you are root). It would be a security leak if
an arbitrary user could suddenly run as another user. Sudo is the escape
mechanism but it runs commands, and is not for changing the uid in the
middle of a process.

>>> >K> I tryed using subprocess but that did not help me either.  I tryed sudo
>>> >K> su into the Popen command but it throws me into the terminal (shell)
>>> >K> with postgres as the user.
>>> 
>>> You could execute the command:
>>> sudo -u postgres required_command
>>> with subprocess.
>>> 
>K> Ok, but the problem is much more complex.
>K> What if I want to do the following.
>K> 1, change the user for a particular script to the postgres user.
>K> 2. now execute the python code for connecting to the postgresql
>K> database.
>K> In the second point I actually want to execute python code not shell
>K> level command so will the sudo -u in the subprocess.Popen change the
>K> user in the script?

You can run another python script as the other user (o even the same
python script). You said you tried subprocess. If that is acceptable
then running another python script should also be acceptable, becaus eit
is basically the same.

>K> In short I would just like to have the script run under another user
>K> let's say postgres as long as a certain action is going on, for example
>K> connecting to the postgresql database.

Why would you have to be another user for connecting to a postgres
database? The DBMS takes care of the permissions at the DB level.

Otherwise you would have to do the DB access in another script. The
script could even communicate withe the original script, e.g by pipes or
some protocol like XMLRPC.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jyoti.mickey at gmail.com  Thu Jul 23 08:30:34 2009
From: jyoti.mickey at gmail.com (Jyoti Sharma)
Date: Thu, 23 Jul 2009 18:00:34 +0530
Subject: how two join and arrange two files together
References: <mailman.3569.1248335802.8015.python-list@python.org>
Message-ID: <op.uxis08tctp94fi@jyotis>

On Thu, 23 Jul 2009 12:52:15 +0530, <amrita at iisermohali.ac.in> wrote:

>
> Hi,
>
> I have two large files:
>
> FileA
> 15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C =
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93.................
>
> and
>
> FileB
> 21 ALA  helix (helix_alpha, helix2)
> 23 ALA  helix (helix_alpha, helix3)
> 38 ALA  helix (helix_alpha, helix3)...........
>
> now what i want that i will make another file in which i will join the  
> two
> file in such a way that only matching entries will come like here 21 and
> 23 ALA is in both files, so the output will be something like:-
>
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA  helix
> (helix_alpha, helix2)
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93|23 ALA  helix (helix_alpha,
> helix3)
>
> and further i will make another file in which i will be able to put those
> lines form this file based on the missing atom value, like for 21 ALA HA
> is not defined so i will put it another file based on its HA missing  
> value
> similarly i will put 23 ALA on another file based on its missing N,CA and
> HA value.
>
> I tried to join the two file based on their matching entries by:---

(snip)

I believe there are packages available for doing such things mostly  
written in perl. But if the aim is not to develop suitable applications  
but only to obtain the desired formatted file then doing this with the  
help of something like Excel would be easiest. This is my opinion from the  
experience I have from my bioinfo programming.

Regards,
Jyoti


From hackingkk at gmail.com  Thu Jul 23 08:30:53 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Thu, 23 Jul 2009 18:00:53 +0530
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <h49ine$cs8$1@ger.gmane.org>
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl> <1248342610.3698.7.camel@krishna-laptop>
	<h49ine$cs8$1@ger.gmane.org>
Message-ID: <1248352253.5100.37.camel@krishna-laptop>

On Thu, 2009-07-23 at 13:50 +0200, paul wrote:

> If the user running python program is allowed to call setuid() then yes.
> 
NO, i don't think i can do that.  I am getting opperation not permitted.

Any ways I think probably subprocess will have to sort it out.

> Did you try running "sudo -u postgres blabla" with subprocess?
> 
Yes, but still not got the intended result which is now obvious.
> > 2. now execute the python code for connecting to the postgresql
> > database.
> > In the second point I actually want to execute python code not shell
> > level command so will the sudo -u in the subprocess.Popen change the
> > user in the script?
> No, as the name "subprocess" suggests you are spawning a new process 
> which gets another uid through sudo. This does not affect the parent 
> process.
> 
Ok then here is the work-around which I am thinking to try, Plese tell
me if it is correct.
I will let that subprocess start python inthe background and execute the
connecting code to postgresql including importing the pygresql library.
Then I will create the connection and cursor objcts in that subprocess.
But my concern is, will the connection object in the child process
(subprocess) be available to the parrent process?


happy hacking.
Krishnakant.




From __peter__ at web.de  Thu Jul 23 08:35:37 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 14:35:37 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
Message-ID: <h49lek$8k0$02$1@news.t-online.com>

superpollo wrote:

> i wrote a program which transforms a string of zeroes ando ones into a
> png file.
> 
> #!/usr/bin/env python
> import Image
> import sys
> bits_in_a_byte = 8
> raster_string = """\
> 00000000000000000000000000000000
> 00100100111100100000100000111100
> 00100100100000100000100000100100
> 00111100111000100000100000100100
> 00100100100000100000100000100100
> 00100100111100111100111100111100
> 00000000000000000000000000000000
> 00000000000000000000000000000000
> 00000000111100100000111100000000
> 00000000100000100000100100000000
> 00000000100000100000111100000000
> 00000000100000100000100000000000
> 00000000111100111100100000000000
> 00000000000000000000000000000000
> """
> raster_lines = raster_string.splitlines()
> high = len(raster_lines)
> wide = len(raster_lines[0])
> bytes_in_a_row = wide/bits_in_a_byte
> bitmap = ""
> for raster_line in raster_lines:
>      for byte_count in range(bytes_in_a_row):
>          first_bit = byte_count*bits_in_a_byte
>          bitmap +=
> chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] , 2))
> im = Image.fromstring("1", (wide , high) , bitmap)
> im.save(sys.stdout , "PNG")
> 
> any suggestions for improvement?

You can simplify the inner loop:

for first_bit in range(0, wide, bits_in_a_byte):
    bitmap += ...

and get rid of a few helper variables.

Here's a different approach:

#!/usr/bin/env python
import Image
import string
import sys

mapping = string.maketrans("01", "\x00\xff")

raster_string = ...

width = raster_string.index("\n")
height = raster_string.count("\n")

raster_string = raster_string.translate(mapping, "\n")

im = Image.fromstring("L", (width, height), raster_string)
im.convert("1").save(sys.stdout, "PNG")

The idea is to move the bit-twiddling from python to code written in C, 
pointless for such a tiny picture but crucial for the performance when you 
want to manipulate larger images.

Peter



From lists at cheimes.de  Thu Jul 23 08:37:07 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 14:37:07 +0200
Subject: Looking for os.listdir() generator
Message-ID: <h49lhh$m57$1@ger.gmane.org>

Hello,

I'm looking for a generator version of os.listdir() for Python 2.5 and
newer. I know somebody has worked on it because I've seen a generator
version in a posting on some list or blog a while ago. I can't find it
anymore. It seems my Google fu is lacking today. All I can find is a
very old version of xlistdir. A Cython based solution is appreciated but
please no ctypes version.

Christian



From python.list at tim.thechases.com  Thu Jul 23 08:39:46 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 23 Jul 2009 07:39:46 -0500
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A684B56.3020906@gmail.com>
References: <4A684B56.3020906@gmail.com>
Message-ID: <4A685A12.4080800@tim.thechases.com>

> until now I used only small / simple databases in Python with sqlite3.
> Now I've a large and rather complex database.
> 
> The most simple query (with just a result of 100 rows),
> takes about 70 seconds.
> And all that time is consumed in "cursor.fetchall"
> 
> Using the same database in Delphi,
> using the same query,
> takes less than 5 seconds (including displaying the full table in a grid).

While it may seem obvious, are you doing anything time-consuming 
with those results?  Or have you tested just doing the fetchall() 
without doing any further processing?  I'm curious on the timing of

   sql = "..."
   start = time()
   cursor.execute(sql)
   rows = cursor.fetchall()
   end = time()
   print end-start

with no other processing.  I regularly write sql that's fairly 
complex and brings back somewhat large datasets (sometimes in 
sqlite), and have never experienced problems with "simple 
quer[ies] (with just a result of 100 rows" taking such 
extrordinary times

The answer from the above code will help determine whether it's 
the sqlite portion that's crazy (and might need some well-placed 
index statements; though if your Delphi code is fine, I suspect 
not), or if it's your application code that goes off into left 
field with the resulting data.

-tkc






From user at example.net  Thu Jul 23 08:41:23 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 14:41:23 +0200
Subject: raster (PIL)
In-Reply-To: <7cr0v1F28dhltU1@mid.uni-berlin.de>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<7cr0v1F28dhltU1@mid.uni-berlin.de>
Message-ID: <4a685a75$0$40009$4fafbaef@reader3.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
...
>>high = len(raster_lines)
>>wide = len(raster_lines[0])
>>bytes_in_a_row = wide/bits_in_a_byte
> 
> 
> This will give you the wrong result if not divideable by bits_in_a_byte. 
> 

then maybe:

#!/usr/bin/env python
import Image
import sys
bits_in_a_byte = 8
raster_string = """\
0000000000000000000000
00100100111100100000100000111100
00100100100000100000100000100100
00111100111000100000100000100100
00100100100000100000100000100100
00100100111100111100111100111100
00000000000000000000000000000000
00000000000000000000000000000000
00000000111100100000111100000000
00000000100000100000100100000000
00000000100000100000111100000000
00000000100000100000100000000000
00000000111100111100100000000000
00000000000000000000000000000000
"""
raster_lines = raster_string.splitlines()
high = len(raster_lines)
wide = len(raster_lines[0])
bytes_in_a_row = wide/bits_in_a_byte
wide_for_real = bytes_in_a_row*bits_in_a_byte
if wide_for_real:
     bitmap = ""
     for raster_line in raster_lines:
         for byte_count in range(bytes_in_a_row):
             first_bit = byte_count*bits_in_a_byte
             bitmap += 
chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] ,
2))
     im = Image.fromstring("1", (wide_for_real , high) , bitmap)
     im.save(sys.stdout , "PNG")

bye


From piet at cs.uu.nl  Thu Jul 23 08:48:29 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 14:48:29 +0200
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
	<b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>
Message-ID: <m2ocrbk1k2.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> On Jul 21, 8:59?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:

>>> The recipient_public_key.pem file is the public key of the recipient
>>> which means the person that is going to receive the encrypted message.
>>> You should get it from the recipient him/herself or from some key store
>>> where s/he has deposited it.
[...]

>j> error coming like - IOError: [Errno 2] No such file or directory:
>j> 'recipient_public_key.pem'

>j> Is this not the inbuilt file.
>j> How should i create such type of file.

You don't create it. See above. If you understand what is is you know
why it can't be builtin. If you don't understand it is better if you
first learn about OpenSSL, otherwise you run the risk to make serious
errors. 

If you are just experimenting to create a message for yourself then you
have to create the public key because you are then the recipient
yourself. That has been answered on
http://stackoverflow.com/questions/1169798/m2crypto-package 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From stephen.cuppett at sas.com  Thu Jul 23 08:48:44 2009
From: stephen.cuppett at sas.com (Stephen Cuppett)
Date: Thu, 23 Jul 2009 08:48:44 -0400
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
Message-ID: <h49m7d$mch$1@foggy.unx.sas.com>

os.environment('QUERY_STRING')


"Fred Atkinson" <fatkinson at mishmash.com> wrote in message 
news:p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj at 4ax.com...
> Is there a pre-defined variable that returns the GET line
> (http://www.php.net/index.php?everythingafterthequestionmark) as a
> single variable (rather than individual variables)?
>
> Regards,
>
>
>
> Fred 




From stephen.cuppett at sas.com  Thu Jul 23 08:50:27 2009
From: stephen.cuppett at sas.com (Stephen Cuppett)
Date: Thu, 23 Jul 2009 08:50:27 -0400
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
Message-ID: <h49mak$mdp$1@foggy.unx.sas.com>

$_SERVER['QUERY_STRING'];

(if it's PHP)

"Fred Atkinson" <fatkinson at mishmash.com> wrote in message 
news:p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj at 4ax.com...
> Is there a pre-defined variable that returns the GET line
> (http://www.php.net/index.php?everythingafterthequestionmark) as a
> single variable (rather than individual variables)?
>
> Regards,
>
>
>
> Fred 




From user at example.net  Thu Jul 23 08:58:45 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 14:58:45 +0200
Subject: raster (PIL)
In-Reply-To: <h49lek$8k0$02$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
Message-ID: <4a685e86$0$40011$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
> superpollo wrote:
> 
> 
>>i wrote a program which transforms a string of zeroes ando ones into a
>>png file.
...
>>any suggestions for improvement?
...
> Here's a different approach:
...
> The idea is to move the bit-twiddling from python to code written in C, 
> pointless for such a tiny picture but crucial for the performance when you 
> want to manipulate larger images.

very very interesting... you know i come from a lower level language 
approach (C/Pascal) so i find it difficult (but full of fascination) to 
adapt to such a different and much simpler way of thinking.

anyways, thanks a lot.

bye



From stef.mientki at gmail.com  Thu Jul 23 09:02:45 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 15:02:45 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A685A12.4080800@tim.thechases.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
Message-ID: <4A685F75.10701@gmail.com>

Tim Chase wrote:
>> until now I used only small / simple databases in Python with sqlite3.
>> Now I've a large and rather complex database.
>>
>> The most simple query (with just a result of 100 rows),
>> takes about 70 seconds.
>> And all that time is consumed in "cursor.fetchall"
>>
>> Using the same database in Delphi,
>> using the same query,
>> takes less than 5 seconds (including displaying the full table in a 
>> grid).
>
> While it may seem obvious, are you doing anything time-consuming with 
> those results?  Or have you tested just doing the fetchall() without 
> doing any further processing?  I'm curious on the timing of
>
>   sql = "..."
>   start = time()
>   cursor.execute(sql)
>   rows = cursor.fetchall()
>   end = time()
>   print end-start
No this is exactly what I did,
I timed the execute and fetchall seperatly:
execute: 125 msec
fetchall: 71000 msec  (returning 100 rows and 25 columns)
pysqlite:  version 2.3.2

btw, I don't know if it's of any importance, the SQL-statement I perform is
select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
  from OPNAMEN
    inner join POID_VLID          on OPNAMEN.POID            = 
POID_VLID.POID
    inner join VRAAGLST           on VRAAGLST.VLID           = 
POID_VLID.VLID
    inner join VLID_SSID          on VRAAGLST.VLID           = 
VLID_SSID.VLID
    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = 
VLID_SSID.SSID
    inner join POID_SSID_SCID     on ( OPNAMEN.POID            = 
POID_SSID_SCID.POID ) and
                                     ( SUBSCHAAL_GEGEVENS.SSID = 
POID_SSID_SCID.SSID )
    inner join SCORES             on SCORES.SCID             = 
POID_SSID_SCID.SCID
    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
    and lower ( NAME_ ) = 'fatigue'
    and TEST_COUNT in (3,4)
    and DATETIME > 39814.0
    and SCORE < 30

cheers,
Stef

>
> with no other processing.  I regularly write sql that's fairly complex 
> and brings back somewhat large datasets (sometimes in sqlite), and 
> have never experienced problems with "simple quer[ies] (with just a 
> result of 100 rows" taking such extrordinary times
>
> The answer from the above code will help determine whether it's the 
> sqlite portion that's crazy (and might need some well-placed index 
> statements; though if your Delphi code is fine, I suspect not), or if 
> it's your application code that goes off into left field with the 
> resulting data.
>
> -tkc
>
>
>
>



From user at example.net  Thu Jul 23 09:02:55 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 15:02:55 +0200
Subject: raster (PIL)
In-Reply-To: <h49lek$8k0$02$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
Message-ID: <4a685f81$0$40008$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
...
> Here's a different approach:
...
> raster_string = ...
> 
> width = raster_string.index("\n")
> height = raster_string.count("\n")

your approach has a funny side-effect: try to remove just one zero from 
the first line of the raster ;-)

bye


From franke.rob at googlemail.com  Thu Jul 23 09:03:06 2009
From: franke.rob at googlemail.com (Robert Franke)
Date: Thu, 23 Jul 2009 15:03:06 +0200
Subject: Pyserial and pyQt
In-Reply-To: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
Message-ID: <d34a96990907230603o543f7dcbi467d2dda3623035@mail.gmail.com>

On Tue, Jul 21, 2009 at 9:37 PM, Seth <king.seth at gmail.com> wrote:

>
> I have used pyserial in the past but this is my first experience with
> pyQt.  I am using the Python xy package for windows current but might
> move to linux.  I have a small device that is outputting a basic text
> string.  I want to be able to read this string(from the comm port) and
> update a text box and eventually a graph in pyQt.  I can't find any
> documentation or tutorials on how to do this.  If anyone can point me
> in the right direction or give me some tips I would be grateful.
>


As I need to do something similar I looked around and found the following
recipe at activestate:

http://code.activestate.com/recipes/82965/

In the comments there is an example for PyQt.


Cheers,
Robert
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/7d2d7348/attachment.html>

From user at example.net  Thu Jul 23 09:16:51 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 15:16:51 +0200
Subject: raster (PIL)
In-Reply-To: <h49lek$8k0$02$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
Message-ID: <4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
...
> im.convert("1").save(sys.stdout, "PNG")
...

a q about pil:

im.convert("1")

is different from:

im2 = im.convert("1")

right?

in the former im is changed (the method applies to im) but in the latter 
im is unchanged (first im is copied unto im2 and then the method is 
applied to im2)... am i right?

bye


From dangets at gmail.com  Thu Jul 23 09:19:33 2009
From: dangets at gmail.com (DG)
Date: Thu, 23 Jul 2009 06:19:33 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst> 
	<mailman.3560.1248307583.8015.python-list@python.org>
Message-ID: <74cd3059-cd88-418b-8444-766a125d93c3@y4g2000prf.googlegroups.com>

On Jul 22, 6:05?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James ?
> <rho... at wildebst.demon.co.uk> escribi?:
>
> > On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina ?
> > <gagsl-... at yahoo.com.ar> wrote:
>
> >> class X(object):
> >> ? ?foo = descriptor()
>
> >> x = X()
> >> x.foo = "value"
>
> > Isn't this going to create a brand new instance attribute x.foo that has ?
> > nothing to do with the descriptor anyway?
>
> No, it's up to the descriptor __set__ method what happens in this case. ?
> Think of the standard 'property' descriptor, the fset function can do ?
> whatever it wants.
> Also, a data descriptor takes precedence over any instance attribute of ?
> the same name that might exist.
>
> --
> Gabriel Genellin

You might've already thought of this (and it is annoying), but you
could pass the name through the descriptor's init method.  I believe
this is the only way besides assigning a metaclass that will look for
that type of descriptor upon class creation and set the descriptor's
name at that time.

class A(object):
    def __init__(self, attr_name):
        self._name = attr_name
    def __set__(self, instance, value):
        self.instance.__dict__[self._name] = value
        # or something like that...

class B(object):
    foo = A('foo')


From breamoreboy at yahoo.co.uk  Thu Jul 23 09:23:27 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Thu, 23 Jul 2009 14:23:27 +0100
Subject: regex: multiple matching for one string
In-Reply-To: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
Message-ID: <h49o7f$vhn$1@ger.gmane.org>

scriptlearner at gmail.com wrote:
> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
> will like to take out the values (valuea, valueb, and valuec).  How do
> I do that in Python?  The group method will only return the matched
> part.  Thanks.
> 
> p = re.compile('#a=*;b=*;c=*;')
> m = p.match(line)
>         if m:
>              print m.group(),

IMHO a regex for this is overkill, a combination of string methods such 
as split and find should suffice.

Regards.



From deets at nospam.web.de  Thu Jul 23 09:27:48 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 15:27:48 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<7cr0v1F28dhltU1@mid.uni-berlin.de>
	<4a685a75$0$40009$4fafbaef@reader3.news.tin.it>
Message-ID: <7cr6qkF28oinaU1@mid.uni-berlin.de>

superpollo wrote:

> Diez B. Roggisch wrote:
>> superpollo wrote:
> ...
>>>high = len(raster_lines)
>>>wide = len(raster_lines[0])
>>>bytes_in_a_row = wide/bits_in_a_byte
>> 
>> 
>> This will give you the wrong result if not divideable by bits_in_a_byte.
>> 
> 
> then maybe:
> 
> #!/usr/bin/env python
> import Image
> import sys
> bits_in_a_byte = 8
> raster_string = """\
> 0000000000000000000000
> 00100100111100100000100000111100
> 00100100100000100000100000100100
> 00111100111000100000100000100100
> 00100100100000100000100000100100
> 00100100111100111100111100111100
> 00000000000000000000000000000000
> 00000000000000000000000000000000
> 00000000111100100000111100000000
> 00000000100000100000100100000000
> 00000000100000100000111100000000
> 00000000100000100000100000000000
> 00000000111100111100100000000000
> 00000000000000000000000000000000
> """
> raster_lines = raster_string.splitlines()
> high = len(raster_lines)
> wide = len(raster_lines[0])
> bytes_in_a_row = wide/bits_in_a_byte
> wide_for_real = bytes_in_a_row*bits_in_a_byte

No. Because that would skip up to 7 bits.

Instead, do

bytes_in_a_row = wide/bits_in_a_byte
if wide % bits_in_a_byte:
   bytes_in_a_row += 1

Diez


From deets at nospam.web.de  Thu Jul 23 09:28:50 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 15:28:50 +0200
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
Message-ID: <7cr6siF28oinaU2@mid.uni-berlin.de>

Fred Atkinson wrote:

> Is there a pre-defined variable that returns the GET line
> (http://www.php.net/index.php?everythingafterthequestionmark) as a
> single variable (rather than individual variables)?

Variables don't return things. Functions do. And additionally the answer
depends on what and with what you actually do.

Diez


From paul at subsignal.org  Thu Jul 23 09:32:10 2009
From: paul at subsignal.org (paul)
Date: Thu, 23 Jul 2009 15:32:10 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <1248352253.5100.37.camel@krishna-laptop>
References: <mailman.3540.1248276934.8015.python-list@python.org>	<m2bpncl5w7.fsf@cs.uu.nl>
	<1248342610.3698.7.camel@krishna-laptop>	<h49ine$cs8$1@ger.gmane.org>
	<1248352253.5100.37.camel@krishna-laptop>
Message-ID: <h49olh$1ft$1@ger.gmane.org>

Krishnakant schrieb:
> On Thu, 2009-07-23 at 13:50 +0200, paul wrote:
> 
>> If the user running python program is allowed to call setuid() then yes.
>>
> NO, i don't think i can do that.  I am getting opperation not permitted.
> 
> Any ways I think probably subprocess will have to sort it out.
> 
>> Did you try running "sudo -u postgres blabla" with subprocess?
>>
> Yes, but still not got the intended result which is now obvious.
Why is that obvious? Works for me:

---- test.py ---------
#!/usr/bin/python

from subprocess import Popen, PIPE

cmd = Popen('sudo -u vboxadd /home/pkoelle/Documents/whoami.sh', 
shell=True, stdout=PIPE, stderr=PIPE)
print "OUT: "+cmd.stdout.read()
print "ERR: "+cmd.stderr.read()

---- whoami.sh -----
#!/bin/bash
echo $UID
logger "whoami script called for $UID"

Of course, you need to adapt path and user values to your situation. The 
user you use in your 'sudo -u <user>...' call needs execute permissions 
for whoami.sh. The relevant entry in /etc/sudoers:

pkoelle ALL=NOPASSWD: /home/pkoelle/Documents/whoami.sh

hth
  Paul

PS: This has absolutely nothing to do with "connecting to postgresql". A 
"postgres user" is not a "system user" (Piet already asked the right 
questions here ;)


>>> 2. now execute the python code for connecting to the postgresql
>>> database.
>>> In the second point I actually want to execute python code not shell
>>> level command so will the sudo -u in the subprocess.Popen change the
>>> user in the script?
>> No, as the name "subprocess" suggests you are spawning a new process 
>> which gets another uid through sudo. This does not affect the parent 
>> process.
>>
> Ok then here is the work-around which I am thinking to try, Plese tell
> me if it is correct.
> I will let that subprocess start python inthe background and execute the
> connecting code to postgresql including importing the pygresql library.
> Then I will create the connection and cursor objcts in that subprocess.
> But my concern is, will the connection object in the child process
> (subprocess) be available to the parrent process?
> 
> 
> happy hacking.
> Krishnakant.
> 
> 



From fatkinson at mishmash.com  Thu Jul 23 09:41:30 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Thu, 23 Jul 2009 06:41:30 -0700
Subject: Predefined Variables
Message-ID: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>

	Is there a pre-defined variable that returns the GET line
(http://www.php.net/index.php?everythingafterthequestionmark) as a
single variable (rather than individual variables)?  

	Regards, 



						Fred 


From __peter__ at web.de  Thu Jul 23 09:43:36 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 15:43:36 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
	<4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <h49pe2$5nk$00$1@news.t-online.com>

superpollo wrote:

> Peter Otten wrote:
> ...
>> im.convert("1").save(sys.stdout, "PNG")
> ...
> 
> a q about pil:
> 
> im.convert("1")
> 
> is different from:
> 
> im2 = im.convert("1")
> 
> right?
> 
> in the former im is changed (the method applies to im) but in the latter
> im is unchanged (first im is copied unto im2 and then the method is
> applied to im2)... am i right?

No. A method has no clue whether its result is used or discarded. Therefore

im.convert("1")

creates a new image in the specified mode, too, which is discarded 
immediately. If you don't need the result you probably shouldn't call the 
method at all.

Peter




From user at example.net  Thu Jul 23 09:57:03 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 15:57:03 +0200
Subject: raster (PIL)
In-Reply-To: <h49pe2$5nk$00$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
	<4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>
	<h49pe2$5nk$00$1@news.t-online.com>
Message-ID: <4a686c30$0$40012$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
> superpollo wrote:
> 
> 
>>Peter Otten wrote:
>>...
>>
>>>im.convert("1").save(sys.stdout, "PNG")
>>
>>...
>>
>>a q about pil:
>>
>>im.convert("1")
>>
>>is different from:
>>
>>im2 = im.convert("1")
>>
>>right?
>>
>>in the former im is changed (the method applies to im) but in the latter
>>im is unchanged (first im is copied unto im2 and then the method is
>>applied to im2)... am i right?
> 
> 
> No. A method has no clue whether its result is used or discarded. Therefore
> 
> im.convert("1")
> 
> creates a new image in the specified mode, too, which is discarded 
> immediately.

but in:

im.convert("1").save(sys.stdout, "PNG")

the new (anonymous) image created by .convert is not discarded 
*immediately*, i mean *before* the .save method is called on it, right?

bye


From paul at boddie.org.uk  Thu Jul 23 10:13:02 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Thu, 23 Jul 2009 07:13:02 -0700 (PDT)
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application 
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org> 
	<h424b1$gj1$1@panix3.panix.com>
	<1c994086-8c58-488f-b3b3-6161c4b2ba05@k30g2000yqf.googlegroups.com>
	<h48mv8$39n$1@panix3.panix.com>
Message-ID: <fcdad95c-551b-4a72-9f05-420f840e93df@h11g2000yqb.googlegroups.com>

On 23 Jul, 05:55, a... at pythoncraft.com (Aahz) wrote:
> In article <1c994086-8c58-488f-b3b3-6161c4b2b... at k30g2000yqf.googlegroups.com>,
> Paul Boddie ?<p... at boddie.org.uk> wrote:
>
> >http://www.boddie.org.uk/python/XSLTools.html
>
> Thanks! ?I'll take a look after OSCON.

The JavaScript parts of the framework are a bit complicated, I'll
admit: you have to write some nasty-looking function calls with
awkward arguments to send AJAX-style requests to the server. I've been
meaning to employ a more declarative "signals and slots" approach so
that you don't have to write in the page templates where the in-page
updates should be expected: it's really the server code that
determines this kind of thing, and so the server code should be able
to say where it wants the page to be updated.

Again, I'll try and put up some examples in the relatively near future
that will make it easier for you to see if it's your kind of thing.

Paul


From __peter__ at web.de  Thu Jul 23 10:19:38 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 16:19:38 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
	<4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>
	<h49pe2$5nk$00$1@news.t-online.com>
	<4a686c30$0$40012$4fafbaef@reader3.news.tin.it>
Message-ID: <h49rhk$khf$02$1@news.t-online.com>

superpollo wrote:

> Peter Otten wrote:
>> superpollo wrote:
>> 
>> 
>>>Peter Otten wrote:
>>>...
>>>
>>>>im.convert("1").save(sys.stdout, "PNG")
>>>
>>>...
>>>
>>>a q about pil:
>>>
>>>im.convert("1")
>>>
>>>is different from:
>>>
>>>im2 = im.convert("1")
>>>
>>>right?
>>>
>>>in the former im is changed (the method applies to im) but in the latter
>>>im is unchanged (first im is copied unto im2 and then the method is
>>>applied to im2)... am i right?
>> 
>> 
>> No. A method has no clue whether its result is used or discarded.
>> Therefore
>> 
>> im.convert("1")
>> 
>> creates a new image in the specified mode, too, which is discarded
>> immediately.
> 
> but in:
> 
> im.convert("1").save(sys.stdout, "PNG")
> 
> the new (anonymous) image created by .convert is not discarded
> *immediately*, i mean *before* the .save method is called on it, right?

Of course. Think of it as a shortcut for

tmp = im.convert(...)
tmp.save(...)
del tmp

Peter




From dangets at gmail.com  Thu Jul 23 10:33:55 2009
From: dangets at gmail.com (DG)
Date: Thu, 23 Jul 2009 07:33:55 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst> 
	<mailman.3560.1248307583.8015.python-list@python.org>
	<74cd3059-cd88-418b-8444-766a125d93c3@y4g2000prf.googlegroups.com>
Message-ID: <e3393507-29c0-4cb7-a62c-edd1ef6ba24d@g23g2000vbr.googlegroups.com>

On Jul 23, 7:19?am, DG <dang... at gmail.com> wrote:
> On Jul 22, 6:05?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>
>
>
> > En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James ?
> > <rho... at wildebst.demon.co.uk> escribi?:
>
> > > On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina ?
> > > <gagsl-... at yahoo.com.ar> wrote:
>
> > >> class X(object):
> > >> ? ?foo = descriptor()
>
> > >> x = X()
> > >> x.foo = "value"
>
> > > Isn't this going to create a brand new instance attribute x.foo that has ?
> > > nothing to do with the descriptor anyway?
>
> > No, it's up to the descriptor __set__ method what happens in this case. ?
> > Think of the standard 'property' descriptor, the fset function can do ?
> > whatever it wants.
> > Also, a data descriptor takes precedence over any instance attribute of ?
> > the same name that might exist.
>
> > --
> > Gabriel Genellin
>
> You might've already thought of this (and it is annoying), but you
> could pass the name through the descriptor's init method. ?I believe
> this is the only way besides assigning a metaclass that will look for
> that type of descriptor upon class creation and set the descriptor's
> name at that time.
>
> class A(object):
> ? ? def __init__(self, attr_name):
> ? ? ? ? self._name = attr_name
> ? ? def __set__(self, instance, value):
> ? ? ? ? self.instance.__dict__[self._name] = value
> ? ? ? ? # or something like that...
>
> class B(object):
> ? ? foo = A('foo')

Well of course I think of more alternatives after I post.
1) still annoying... pass the class through a 'registering' function
that will examine all of it's attrs and find the ones that are of your
descriptor type, and assign the attr_name upon that descriptor.name
attribute.

2) I just thought of, and it's kind of a hack is to do this
examination within the '__set__' method.
e.g.

class A(object):
    def __get__(self, instance, owner):
        if instance is None:
            return self
        else:
            # do something different here for instances' access
            return self

    def __set__(self, instance, value):
        cls = instance.__class__
        name = None
        for attr in dir(cls):
            if getattr(cls, attr) is self:
                name = attr
        print name


From amrita at iisermohali.ac.in  Thu Jul 23 10:34:15 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Thu, 23 Jul 2009 20:04:15 +0530 (IST)
Subject: how two join and arrange two files together
In-Reply-To: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
References: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
Message-ID: <20373.210.212.36.65.1248359655.squirrel@www.iisermohali.ac.in>

I tried to print those lines having C value missing by:

import re
expr = re.compile("C = None")
f = open("/home/amrita/helix.dat")
for line in f:
    if expr.search(line):
       print line

but it is not giving any value.

>
> Hi,
>
> I have two large files:
>
> FileA
> 15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C =
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93.................
>
> and
>
> FileB
> 21 ALA  helix (helix_alpha, helix2)
> 23 ALA  helix (helix_alpha, helix3)
> 38 ALA  helix (helix_alpha, helix3)...........
>
> now what i want that i will make another file in which i will join the two
> file in such a way that only matching entries will come like here 21 and
> 23 ALA is in both files, so the output will be something like:-
>
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA  helix
> (helix_alpha, helix2)
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93|23 ALA  helix (helix_alpha,
> helix3)
>
> and further i will make another file in which i will be able to put those
> lines form this file based on the missing atom value, like for 21 ALA HA
> is not defined so i will put it another file based on its HA missing value
> similarly i will put 23 ALA on another file based on its missing N,CA and
> HA value.
>
> I tried to join the two file based on their matching entries by:---
>>>>from collections import defaultdict
>>>>
>>>> if __name__ == "__main__":
> ...      a = open("/home/amrita/alachems/chem100.txt")
> ...      c = open("/home/amrita/secstr/secstr100.txt")
> ...
>>>> def source(stream):
> ...     return (line.strip() for line in stream)
> ...
> ...
>>>> def merge(sources):
> ...     for m in merge([source(a),source(c)]):
> ...         print "|".join(c.ljust(10) for c in m)
> ...
>
> but it is not giving any value.
>
>
>
>
>
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From rhodri at wildebst.demon.co.uk  Thu Jul 23 10:39:15 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 23 Jul 2009 15:39:15 +0100
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxhuj5olx6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst>
	<op.uxhuj5olx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <op.uxiyzpkla8ncjz@gnudebst>

On Thu, 23 Jul 2009 01:05:55 +0100, Gabriel Genellina  
<gagsl-py2 at yahoo.com.ar> wrote:

> En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James  
> <rhodri at wildebst.demon.co.uk> escribi?:
>> On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina  
>> <gagsl-py2 at yahoo.com.ar> wrote:
>>
>>
>>> class X(object):
>>>    foo = descriptor()
>>>
>>> x = X()
>>> x.foo = "value"
>>
>> Isn't this going to create a brand new instance attribute x.foo that  
>> has nothing to do with the descriptor anyway?
>
> No, it's up to the descriptor __set__ method what happens in this case.  
> Think of the standard 'property' descriptor, the fset function can do  
> whatever it wants.

If it gets called, that is.

> Also, a data descriptor takes precedence over any instance attribute of  
> the same name that might exist.

This was the bit I wasn't clear on.  Thanks!

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From manu3d at gmail.com  Thu Jul 23 10:44:50 2009
From: manu3d at gmail.com (Emanuele D'Arrigo)
Date: Thu, 23 Jul 2009 07:44:50 -0700 (PDT)
Subject: import vs imp and friends.
Message-ID: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>

Greetings,

I was looking in the archive of this newsgroup and I found this
snippet:

import imp
sourcecode = 'def foo(x): return 11*x'
mod = imp.new_module('foo')
exec sourcecode in mod.__dict__
mod.foo(16)

Together with similar and sometimes more complete snippets available
they show how a module can be created out of string, plain text files
and compiled files. Neat!

Now the question. Apart from checking sys.module first and eventually
adding the new module to it if it isn't there already, and apart from
setting __file__, is there anything else that import does and this
snippet doesn't?

Manu


From MLists at romulo.de  Thu Jul 23 10:44:56 2009
From: MLists at romulo.de (Rainer Mansfeld)
Date: Thu, 23 Jul 2009 16:44:56 +0200
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A687768.2050804@romulo.de>

Gabriel Genellina schrieb:
> I have a class attribute 'foo' which is a data descriptor. I create an 
> instance of such class. When I say instance.foo = value, the descriptor 
> __set__ method is called. Is there any way to obtain the name being 
> assigned to? ('foo' in this example). That is, I want to know the target 
> name for the assignment that triggered the __set__ method call.
> 

class descriptor(object):
     def __get__(self, instance, owner):
       return self

     def __set__(self, instance, value):
         # I want to know the *name* this value is being assigned to
         for name in instance.__class__.__dict__:
             if getattr(instance, name) is self:
                 print "assigning to %s" % name
                 break


class X(object):
     foo = descriptor()
     bar = descriptor()

class Y(object):
     foo = descriptor()
     baz = descriptor()

x = X()
y = Y()

x.foo = "value"
x.bar = "value"
y.foo = "value"
y.baz = "value"

Does this work for you?

    Rainer



From luismgz at gmail.com  Thu Jul 23 10:53:48 2009
From: luismgz at gmail.com (Neuruss)
Date: Thu, 23 Jul 2009 07:53:48 -0700 (PDT)
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org> 
	<0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com> 
	<mailman.3347.1247899831.8015.python-list@python.org>
Message-ID: <649b38ef-fced-457e-953a-ffaf2fd9012e@c29g2000yqd.googlegroups.com>

It seems psyco.org is still in the transfer process...
Is there any charitable soul with a link to a Windows binary? :-)


From lists at cheimes.de  Thu Jul 23 11:04:05 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 17:04:05 +0200
Subject: import vs imp and friends.
In-Reply-To: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
References: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
Message-ID: <h49u54$lfs$1@ger.gmane.org>

Emanuele D'Arrigo wrote:
> Now the question. Apart from checking sys.module first and eventually
> adding the new module to it if it isn't there already, and apart from
> setting __file__, is there anything else that import does and this
> snippet doesn't?

The import statement does several things. For instance it holds the
import lock to stop other threads from importing the same module again.
It also does lots of additional work for packages like relative imports,
checking __path__, setting attributes on parent packages and so on. The
import system also does a lot of work in order to find and load a
module, too.

Christian





From lists at cheimes.de  Thu Jul 23 11:17:42 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 17:17:42 +0200
Subject: ANN: psyco V2
In-Reply-To: <649b38ef-fced-457e-953a-ffaf2fd9012e@c29g2000yqd.googlegroups.com>
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>
	<mailman.3347.1247899831.8015.python-list@python.org>
	<649b38ef-fced-457e-953a-ffaf2fd9012e@c29g2000yqd.googlegroups.com>
Message-ID: <4A687F16.3030501@cheimes.de>

Neuruss wrote:
> It seems psyco.org is still in the transfer process...
> Is there any charitable soul with a link to a Windows binary? :-)

It seems like Christian is already working on Windows binaries. We are
having a discussing about an obscure MinGW bug on the Python developer
list. It looks like MinGW isn't fully ABI compatible with MSVC.

Christian


From lists at cheimes.de  Thu Jul 23 11:22:55 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 17:22:55 +0200
Subject: ANN: psyco V2
In-Reply-To: <4A5FE13A.3080708__12565.7702716582$1247820318$gmane$org@stackless.com>
References: <4A5FE13A.3080708__12565.7702716582$1247820318$gmane$org@stackless.com>
Message-ID: <4A68804F.4030802@cheimes.de>

Christian Tismer wrote:
> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
> is well being considered.

Can you estimate how much work needs to be done in order to get Psyco
working on 64bit POSIX (Linux) systems?

Christian



From Aaron.Dushku at ma.usda.gov  Thu Jul 23 11:27:34 2009
From: Aaron.Dushku at ma.usda.gov (Dushku, Aaron - Amherst, MA)
Date: Thu, 23 Jul 2009 10:27:34 -0500
Subject: Office COM automatisation - calling python from VBA
Message-ID: <7B11445876E166488E821C88E5A18778032F136CA3@mostlouis7s302.agent.one.usda.gov>

I'd like a copy of that code.  Thanks for taking the time for all of us.


Sincerely,
Aaron Dushku


******************************
Aaron Dushku
GIS Specialist
USDA-NRCS
Amherst, Massachusetts
(413) 253-4379
Email:  aaron.dushku at ma.usda.gov


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/f65f6700/attachment.html>

From drakonik at gmail.com  Thu Jul 23 11:29:01 2009
From: drakonik at gmail.com (Nick Dumas)
Date: Thu, 23 Jul 2009 11:29:01 -0400
Subject: regex: multiple matching for one string
In-Reply-To: <mailman.3588.1248355389.8015.python-list@python.org>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
Message-ID: <zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Agreed. Two string.split()s, first at the semi-colon and then at the
equal sign, will yield you your value, without having to fool around
with regexes.

On 7/23/2009 9:23 AM, Mark Lawrence wrote:
> scriptlearner at gmail.com wrote:
>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>> will like to take out the values (valuea, valueb, and valuec).  How do
>> I do that in Python?  The group method will only return the matched
>> part.  Thanks.
>>
>> p = re.compile('#a=*;b=*;c=*;')
>> m = p.match(line)
>>         if m:
>>              print m.group(),
> 
> IMHO a regex for this is overkill, a combination of string methods such
> as split and find should suffice.
> 
> Regards.
> 
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAkpogb0ACgkQLMI5fndAv9jtOwCgj3+YOLfKGvAdyCMOhh4NGgfy
x5YAn1ydhUYxGlvC4Z4WlWKaa1gwviSh
=jnp1
-----END PGP SIGNATURE-----


From leerisq at gmail.com  Thu Jul 23 11:33:39 2009
From: leerisq at gmail.com (LeeRisq)
Date: Thu, 23 Jul 2009 08:33:39 -0700 (PDT)
Subject: win32clipboard operation
Message-ID: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>

Hi all,

Newbie question. I've written a script that outputs to a text file.

Now, I just want to copy the content to win32clipboard for access to
other applications. Here's the mess I've come up with so far:)

import xlrd
import win32clipboard



def program_uno():
    ofile = open(r"C:\Query\DQL.txt", "w")
    book = xlrd.open_workbook("C:\DocLoader\MCL_Drawing and Legacy
Docloader Sheet.xls")
    sh = book.sheet_by_index(0)
    e = sh.cell_value(1, 0)
    a = sh.col_values(0, start_rowx=2, end_rowx=200)
    b = r'%' + e
    c = r'%Draft%'
    y = r"some text..." %(b, c)
    w = r"some more text..."
    ofile.writelines(y)
    for x in a:
        d = r'%' + x
        z = r" loop text..." %(d, c)
        f = ofile.writelines(z)
    ofile.writelines(w)


def copy_text():
    ifile = open(r"C:\Query\DQL.txt", "r")


    win32clipboard.OpenClipboard(0)
    win32clipboard.EmptyClipboard()
    win32clipboard.SetClipboardText()
    win32clipboard.CloseClipboard

program_uno()
copy_text()


From vinay_sajip at yahoo.co.uk  Thu Jul 23 11:39:50 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Thu, 23 Jul 2009 08:39:50 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
Message-ID: <716ee910-452b-4872-b4eb-5f280344c990@n11g2000yqb.googlegroups.com>

On Jul 23, 4:06 am, Naoki INADA <songofaca... at gmail.com> wrote:
> In document <http://docs.python.org/library/
> stdtypes.html#file.encoding>:
>
> >> The encoding that this file uses. When Unicode strings are written to a file,
> >>  they will be converted to byte strings using this encoding. In addition,
> >> when the file is connected to a terminal, the attribute gives the encoding
> >> that the terminal is likely to use
>
> But inlogging.StreamHandler.emit() ::
>
>                 try:
>                     if (isinstance(msg, unicode) and
>                         getattr(stream, 'encoding', None)):
>                         #fs = fs.decode(stream.encoding)
>                         try:
>                             stream.write(fs % msg)
>                         except UnicodeEncodeError:
>                             #Printing to terminals sometimes fails.
> For example,
>                             #with an encoding of 'cp1251', the above
> write will
>                             #work if written to a stream opened or
> wrapped by
>                             #the codecs module, but fail when writing
> to a
>                             #terminal even when the codepage is set to
> cp1251.
>                             #An extra encoding step seems to be
> needed.
>                             stream.write((fs % msg).encode
> (stream.encoding))
>                     else:
>                         stream.write(fs % msg)
>                 except UnicodeError:
>                     stream.write(fs % msg.encode("UTF-8"))
>
> And behavior of sys.stdout in Windows::>>> import sys
> >>> sys.stdout.encoding
> 'cp932'
> >>> u = u"???"
> >>> u
>
> u'\u3042\u3044\u3046'>>> print >>sys.stdout, u
> ???
> >>> sys.stderr.write(u)
>
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> UnicodeEncodeError: 'ascii' codec can't encode characters in position
> 0-2: ordinal not in range(128)
>
> What is file.encoding convention?
> If I want to write a unicode string to a file(-like) that have
> encoding attribute, I should do
> (1) try: file.write(unicode_str),
> (2) except UnicodeEncodeError: file.write(unicode_str.encode
> (file.encoding))
> likelogging?
> It seems agly.

If you are writing a Unicode string to a stream which has been opened
with e.g. codecs.open with a specific encoding, then the stream is
actually a wrapper. You can write Unicode strings directly to it, and
the wrapper stream will encode the Unicode to bytes using the specific
encoding and write those bytes to the underlyting stream. In your
example you didn't show sys.stderr.encoding - you showed
sys.stdout.encoding and printed out something to it which seemed to
give the correct result, but then wrote to sys.stderr which gave a
UnicodeEncodeError. What is the encoding of sys.stderr in your
example? Also note that logging had to handle what appeared to be an
oddity with terminals - they (at least sometimes) have an encoding
attribute but appear to expect to have bytes written to them, and not
Unicode. Hence the logging kludge, which should not be needed and so
has been carefully commented.

Regards,

Vinay Sajip


From Bill at SynectixLtd.com  Thu Jul 23 11:44:50 2009
From: Bill at SynectixLtd.com (Bill Davy)
Date: Thu, 23 Jul 2009 16:44:50 +0100
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
Message-ID: <7creq2F29npujU1@mid.individual.net>

"Mark Lawrence" <breamoreboy at yahoo.co.uk> wrote in message 
news:mailman.3588.1248355389.8015.python-list at python.org...
> scriptlearner at gmail.com wrote:
>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>> will like to take out the values (valuea, valueb, and valuec).  How do
>> I do that in Python?  The group method will only return the matched
>> part.  Thanks.
>>
>> p = re.compile('#a=*;b=*;c=*;')
>> m = p.match(line)
>>         if m:
>>              print m.group(),
>
> IMHO a regex for this is overkill, a combination of string methods such as 
> split and find should suffice.
>
> Regards.
>


For the OP, it can be done with regex by grouping:

p = re.compile(r'#a=(*);b=(*);c=(*);')
m = p.match(line)
       if m:
             print m.group(1),

m.group(1) has valuea in it, etc.

But this may not be the best way, but it is reasonably terse. 




From icebergwtf at gmail.com  Thu Jul 23 11:46:04 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Thu, 23 Jul 2009 23:46:04 +0800
Subject: extract c/cpp include file with regular expression
Message-ID: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>

Hi all!
I need to parse c/cpp source files, one requirement is to extract
included header file name.
here is my solution:
>>> p = re.compile(r'#\s*include\s+(?:(<)|("))(.*)(?(1)>)(?(2)")')
>>> m = re.search(p, '#include <header.h>')
>>> m.group(3)
'header.h'
>>> m = re.search(p, '#include "header.h"')
>>> m.group(3)
'header.h'
>>> m = re.search(p, '#include <header.h"')
>>> print(m)
None
>>> m = re.search(p, '#include "header.h>')
>>> print(m)
None

Pretty ugly! And I know for a valid c/cpp source file, it will be not
necessary to check and match '<' with '>' and " with ",
but I'm wondering to see more elegant way to do such thing.

tiefeng wu
2009-07-23


From victorsubervi at gmail.com  Thu Jul 23 11:46:16 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Thu, 23 Jul 2009 12:46:16 -0300
Subject: Cannot Get Form To Work
Message-ID: <4dc0cfea0907230846g4f593219t308c64eec4943f93@mail.gmail.com>

Hi:
When the form comes up the first time, there is the default value for num.
When I fill in a number in the form and press send, even though the form
sends to itself (same page name), I would think it would read the number
sent. Here again is the code:

from primeNumbers import primeNumbers

try:
 lang = form.getfirst('lang', 'en')
 browser = form.getfirst('browser', 'all')
 site = form.getfirst('site', 'bridge')
 num = form.getfirst('num','')
except:
 pass

ourFile = string.split(__file__, "/")
p = ourFile[len(ourFile) - 1]
p = p[: - 9]
site = ourFile[4][:-10]
if site != '':
 site = site[:-1]

print "Content-Type: text/html"
print
print """
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<head xmlns="http://www.w3.org/1999/xhtml">
</head>
"""
if num != '':
 num = round(float(num))
 roots = primeNumbers(num)
 print roots
if num == '':
 print """
<form action="http://13gems.com/test-Calculators_frame.py" method="post">
<input type="text" name="num" size="20" maxlength="20" value="Enter number
here..." onfocus="this.value=''" />
<input type="image" src="http://13gems.com/images/search.jpg" name="search"
id="search" />
</form>
"""
print '</body></html>\n'
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/4dde2fb9/attachment.html>

From dr.mtarver at ukonline.co.uk  Thu Jul 23 11:48:46 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Thu, 23 Jul 2009 08:48:46 -0700 (PDT)
Subject: strange python scripting error
Message-ID: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>

I have a very strange error.  I have two test python files test.py and
python.py which contain the following code

#!/usr/bin/python
print "Content-type: text/html"
print
print "<html>"
print "<center>Hello, Linux.com!</center>"
print "</html>"

One file (test.py) works; you call it up and it shows a web page with

Hello, Linux.com

The other fails with a server configuration error.  Both are running
under Linux, same server, same permissions.  Running a character scan
shows that both files contain the same printable characters and are
therefore typographically identical.   They are absolutely the same.

The only hint at a difference I can see is that my ftp program says
the files are of unequal lengths.  test.py is 129 bytes long.
python.py 134 bytes long.

A zipped folder containing both files is at

www.lambdassociates.org/weird.zip

Any ideas welcome.

Mark


From icebergwtf at gmail.com  Thu Jul 23 11:54:01 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Thu, 23 Jul 2009 23:54:01 +0800
Subject: regex: multiple matching for one string
In-Reply-To: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
Message-ID: <4314c1f70907230854qcb85dc1vde5fede76b0c80ff@mail.gmail.com>

2009/7/23 scriptlearner at gmail.com <scriptlearner at gmail.com>:
> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
> will like to take out the values (valuea, valueb, and valuec). ?How do
> I do that in Python? ?The group method will only return the matched
> part. ?Thanks.
>
> p = re.compile('#a=*;b=*;c=*;')
> m = p.match(line)
> ? ? ? ?if m:
> ? ? ? ? ? ? print m.group(),
> --
> http://mail.python.org/mailman/listinfo/python-list
>

maybe like this:
>>> p = re.compile(r'#?\w+=(\w+);')
>>> l = re.findall(p, '#a=valuea;b=valueb;c=valuec;')
>>> for r in l: print(r)
...
valuea
valueb
valuec

tiefeng wu
2009-07-23


From deets at nospam.web.de  Thu Jul 23 11:57:44 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 17:57:44 +0200
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
Message-ID: <7crfjoF29e4gtU1@mid.uni-berlin.de>

Mark Tarver wrote:

> I have a very strange error.  I have two test python files test.py and
> python.py which contain the following code
> 
> #!/usr/bin/python
> print "Content-type: text/html"
> print
> print "<html>"
> print "<center>Hello, Linux.com!</center>"
> print "</html>"
> 
> One file (test.py) works; you call it up and it shows a web page with
> 
> Hello, Linux.com
> 
> The other fails with a server configuration error.  Both are running
> under Linux, same server, same permissions.  Running a character scan
> shows that both files contain the same printable characters and are
> therefore typographically identical.   They are absolutely the same.
> 
> The only hint at a difference I can see is that my ftp program says
> the files are of unequal lengths.  test.py is 129 bytes long.
> python.py 134 bytes long.
> 
> A zipped folder containing both files is at
> 
> www.lambdassociates.org/weird.zip
> 
> Any ideas welcome.

They have different line-ending-conventions. Not sure if and why that makes
a difference.

Diez


From philip at semanchuk.com  Thu Jul 23 11:58:13 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 11:58:13 -0400
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
Message-ID: <CE27720A-C736-4670-AF63-6164A859BA4F@semanchuk.com>


On Jul 23, 2009, at 11:46 AM, tiefeng wu wrote:

> Hi all!
> I need to parse c/cpp source files, one requirement is to extract
> included header file name.
> here is my solution:
>>>> p = re.compile(r'#\s*include\s+(?:(<)|("))(.*)(?(1)>)(?(2)")')
>>>> m = re.search(p, '#include <header.h>')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include "header.h"')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include <header.h"')
>>>> print(m)
> None
>>>> m = re.search(p, '#include "header.h>')
>>>> print(m)
> None
>
> Pretty ugly! And I know for a valid c/cpp source file, it will be not
> necessary to check and match '<' with '>' and " with ",
> but I'm wondering to see more elegant way to do such thing.

Hi tiefeng,
Regexes are always a little ugly IMO. =)

A side note -- does your parser need to handle /* comments like this  
one*/?  If so, then regular expressions are not going be sufficient.

Good luck
Philip



From python at mrabarnett.plus.com  Thu Jul 23 12:05:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 17:05:09 +0100
Subject: win32clipboard operation
In-Reply-To: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
Message-ID: <4A688A35.3080107@mrabarnett.plus.com>

LeeRisq wrote:
> Hi all,
> 
> Newbie question. I've written a script that outputs to a text file.
> 
> Now, I just want to copy the content to win32clipboard for access to
> other applications. Here's the mess I've come up with so far:)
> 
[snip]

def copy_text():
     ifile = open(r"C:\Query\DQL.txt", "r")
     text = ifile.read()
     ifile.close()

     win32clipboard.OpenClipboard()
     win32clipboard.EmptyClipboard()
     win32clipboard.SetClipboardText(text)
     win32clipboard.CloseClipboard()



From dstanek at dstanek.com  Thu Jul 23 12:09:55 2009
From: dstanek at dstanek.com (David Stanek)
Date: Thu, 23 Jul 2009 12:09:55 -0400
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A685F75.10701@gmail.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<4A685F75.10701@gmail.com>
Message-ID: <de32cc030907230909u35979708seb76c7193b31105@mail.gmail.com>

On Thu, Jul 23, 2009 at 9:02 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
>
> btw, I don't know if it's of any importance, the SQL-statement I perform is
> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
> ?from OPNAMEN
> ? inner join POID_VLID ? ? ? ? ?on OPNAMEN.POID ? ? ? ? ? ?= POID_VLID.POID
> ? inner join VRAAGLST ? ? ? ? ? on VRAAGLST.VLID ? ? ? ? ? = POID_VLID.VLID
> ? inner join VLID_SSID ? ? ? ? ?on VRAAGLST.VLID ? ? ? ? ? = VLID_SSID.VLID
> ? inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
> ? inner join POID_SSID_SCID ? ? on ( OPNAMEN.POID ? ? ? ? ? ?=
> POID_SSID_SCID.POID ) and
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?( SUBSCHAAL_GEGEVENS.SSID =
> POID_SSID_SCID.SSID )
> ? inner join SCORES ? ? ? ? ? ? on SCORES.SCID ? ? ? ? ? ? =
> POID_SSID_SCID.SCID
> ? inner join PID_POID ? ? ? ? ? on OPNAMEN.POID ? ? ? ? ? ?= PID_POID.POID
> ? inner join PATIENT ? ? ? ? ? ?on PATIENT.PID ? ? ? ? ? ? = PID_POID.PID
> ?where substr ( lower( NAME) , 1, 6) ?= 'cis20r'
> ? and lower ( NAME_ ) = 'fatigue'
> ? and TEST_COUNT in (3,4)
> ? and DATETIME > 39814.0
> ? and SCORE < 30

Warning: I suck at SQL and hate it with a passion...

By using lower() on the left side of the where expressions I believe
that you are table scanning. So it is not the size of the data
returned, but the size of the data that needs to be scanned.

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From R.Brodie at rl.ac.uk  Thu Jul 23 12:11:21 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Thu, 23 Jul 2009 17:11:21 +0100
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<7crfjoF29e4gtU1@mid.uni-berlin.de>
Message-ID: <h4a23a$mp4$1@south.jnrs.ja.net>


"Diez B. Roggisch" <deets at nospam.web.de> wrote in message 
news:7crfjoF29e4gtU1 at mid.uni-berlin.de...

> They have different line-ending-conventions. Not sure if and why that makes
> a difference.

Depends on your setup. Shells can be a bit dumb about it, so
it will likely break simple cgi-style hosting.

-bash: ./python.py: /usr/bin/python^M: bad interpreter: 




From python at mrabarnett.plus.com  Thu Jul 23 12:13:02 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 17:13:02 +0100
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
Message-ID: <4A688C0E.6040705@mrabarnett.plus.com>

tiefeng wu wrote:
> Hi all!
> I need to parse c/cpp source files, one requirement is to extract
> included header file name.
> here is my solution:
>>>> p = re.compile(r'#\s*include\s+(?:(<)|("))(.*)(?(1)>)(?(2)")')
>>>> m = re.search(p, '#include <header.h>')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include "header.h"')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include <header.h"')
>>>> print(m)
> None
>>>> m = re.search(p, '#include "header.h>')
>>>> print(m)
> None
> 
> Pretty ugly! And I know for a valid c/cpp source file, it will be not
> necessary to check and match '<' with '>' and " with ",
> but I'm wondering to see more elegant way to do such thing.
> 
I'd probably do:

 >>> p = re.compile(r'#\s*include\s+(?:<([^>]*)>|"([^"]*)")')
 >>> m = p.search('#include <header.h>')
 >>> m.group(1) or m.group(2)
'header.h'


From __peter__ at web.de  Thu Jul 23 12:14:03 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 18:14:03 +0200
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<7crfjoF29e4gtU1@mid.uni-berlin.de>
Message-ID: <h4a285$nvl$00$1@news.t-online.com>

Diez B. Roggisch wrote:

> Mark Tarver wrote:
> 
>> I have a very strange error.  I have two test python files test.py and
>> python.py which contain the following code
>> 
>> #!/usr/bin/python
>> print "Content-type: text/html"
>> print
>> print "<html>"
>> print "<center>Hello, Linux.com!</center>"
>> print "</html>"
>> 
>> One file (test.py) works; you call it up and it shows a web page with
>> 
>> Hello, Linux.com
>> 
>> The other fails with a server configuration error.  Both are running
>> under Linux, same server, same permissions.  Running a character scan
>> shows that both files contain the same printable characters and are
>> therefore typographically identical.   They are absolutely the same.
>> 
>> The only hint at a difference I can see is that my ftp program says
>> the files are of unequal lengths.  test.py is 129 bytes long.
>> python.py 134 bytes long.
>> 
>> A zipped folder containing both files is at
>> 
>> www.lambdassociates.org/weird.zip
>> 
>> Any ideas welcome.
> 
> They have different line-ending-conventions. Not sure if and why that
> makes a difference.

Looks like the shell treats the CR as part of the interpreter name:

$ cat python.py
#!/usr/bin/python
print "Content-type: text/html"
print
print "<html>"
print "<center>Hello, Linux.com!</center>"
print "</html>"$
$ python python.py
Content-type: text/html

<html>
<center>Hello, Linux.com!</center>
</html>
$ chmod u+x python.py
$ ./python.py
bash: ./python.py: /usr/bin/python^M: bad interpreter: No such file or 
directory

Peter



From dangets at gmail.com  Thu Jul 23 12:21:15 2009
From: dangets at gmail.com (DG)
Date: Thu, 23 Jul 2009 09:21:15 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<mailman.3593.1248362137.8015.python-list@python.org>
Message-ID: <edc10982-6271-41ca-b500-99b2c48966d5@d23g2000vbm.googlegroups.com>

On Jul 23, 8:44?am, Rainer Mansfeld <MLi... at romulo.de> wrote:
> Gabriel Genellina schrieb:
>
> > I have a class attribute 'foo' which is a data descriptor. I create an
> > instance of such class. When I say instance.foo = value, the descriptor
> > __set__ method is called. Is there any way to obtain the name being
> > assigned to? ('foo' in this example). That is, I want to know the target
> > name for the assignment that triggered the __set__ method call.
>
> class descriptor(object):
> ? ? ?def __get__(self, instance, owner):
> ? ? ? ?return self
>
> ? ? ?def __set__(self, instance, value):
> ? ? ? ? ?# I want to know the *name* this value is being assigned to
> ? ? ? ? ?for name in instance.__class__.__dict__:
> ? ? ? ? ? ? ?if getattr(instance, name) is self:
> ? ? ? ? ? ? ? ? ?print "assigning to %s" % name
> ? ? ? ? ? ? ? ? ?break
>
> class X(object):
> ? ? ?foo = descriptor()
> ? ? ?bar = descriptor()
>
> class Y(object):
> ? ? ?foo = descriptor()
> ? ? ?baz = descriptor()
>
> x = X()
> y = Y()
>
> x.foo = "value"
> x.bar = "value"
> y.foo = "value"
> y.baz = "value"
>
> Does this work for you?
>
> ? ? Rainer

The reason I wasn't checking the class' '__dict__' attribute in my
solution was because this won't show any descriptors that were
inherited from base classes.  Example with some optimizations below
(sorry for the long code):

builtin_methods = dir(object)

class descriptor(object):
    def __init__(self):
        self.name = None

    def __get__(self, instance, owner):
        # if you want a 'useful' data descriptor only return self upon
        # non-instance access
        if instance is None:
            return self
        else:
            # do something besides the below for the usefulness
            return self

    def __set__(self, instance, value):
        if self.name is None:
            cls = instance.__class__
            dir_attrs = [m for m in dir(cls) if m not in
builtin_methods]
            # 'foo' is printed here
            print 'dir(cls):    ', dir_attrs
            # 'foo' is not printed here
            print 'cls.__dict__:', cls.__dict__
            for name in dir_attrs:
                if getattr(cls, name) is self:
                    self.name = name
        print "setting %s to %s" % (self.name, value)


class baseX(object):
    foo = descriptor()

class X(baseX):
    pass

x = X()
x.foo = 'bar'



From icebergwtf at gmail.com  Thu Jul 23 12:21:41 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Fri, 24 Jul 2009 00:21:41 +0800
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4A688C0E.6040705@mrabarnett.plus.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
	<4A688C0E.6040705@mrabarnett.plus.com>
Message-ID: <4314c1f70907230921j2a5eacd0n1fdac763765b922f@mail.gmail.com>

MRAB wrote:
> I'd probably do:
>
>>>> p = re.compile(r'#\s*include\s+(?:<([^>]*)>|"([^"]*)")')
>>>> m = p.search('#include <header.h>')
>>>> m.group(1) or m.group(2)
> 'header.h'
>

yes, it's easier to understand.
thanks, MRAB!
I always make things complicated :P

tiefeng wu
2009-07-23


From icebergwtf at gmail.com  Thu Jul 23 12:36:53 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Fri, 24 Jul 2009 00:36:53 +0800
Subject: extract c/cpp include file with regular expression
In-Reply-To: <35D1D3C1-ECC3-4FEC-A21E-C6A17D9E22D7@semanchuk.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
	<CE27720A-C736-4670-AF63-6164A859BA4F@semanchuk.com>
	<4314c1f70907230913t76567a7cm3b3e4649f5bc6e4e@mail.gmail.com>
	<35D1D3C1-ECC3-4FEC-A21E-C6A17D9E22D7@semanchuk.com>
Message-ID: <4314c1f70907230936w51881daaja30e1abf73742ad2@mail.gmail.com>

2009/7/24 Philip Semanchuk <philip at semanchuk.com>:
>
> I know this will sound like a sarcastic comment, but it is sincere: my
> suggestion is that if you want to parse C/C++ (or Python, or Perl, or
> Fortran, etc.), use a real parser, not regexes unless you're willing to
> sacrifice some accuracy. Sooner or later you'll come across some code that
> your regexes won't handle, like this --
>
> #ifdef FOO_BAR
> #include <this.h>
> /* #else */
> #include <that.h>
> #endif
>
>
> Parsing code is difficult...
>
I understand your point, thanks for your suggestion, Philip. And I've
met the problem like in your example
The reason I choose regex because I barely know about "real parser",
for me it still in some "dark area" :)
But I'll find something to learn.

tiefeng wu
2009-07-23


From tismer at stackless.com  Thu Jul 23 12:41:36 2009
From: tismer at stackless.com (Christian Tismer)
Date: Thu, 23 Jul 2009 09:41:36 -0700
Subject: ANN: psyco V2
In-Reply-To: <4A68804F.4030802@cheimes.de>
References: <4A5FE13A.3080708__12565.7702716582$1247820318$gmane$org@stackless.com>
	<4A68804F.4030802@cheimes.de>
Message-ID: <4A6892C0.40104@stackless.com>

On 7/23/09 8:22 AM, Christian Heimes wrote:
> Christian Tismer wrote:
>> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
>> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
>> is well being considered.
>
> Can you estimate how much work needs to be done in order to get Psyco
> working on 64bit POSIX (Linux) systems?

This is not easy to tell. I'm in the process of estimating
this, because my sponsor wants to know as well. They are
very interested, but it has to be somehow affordable in
time and money.

There are different paths that can be taken. Simply hacking away,
trying to go straight to 64 bit is obvious, but probably a bad
approach. Half of the system needs to be rewritten and augmented
with extra size info, and this goes very deep. I think this
way I would produce a nightmare of even more complicated code,
and would kill myself debugging-wise.

I believe I need to simplify psyco and make many parts more
abstract and more general, to become able to make it flexible.
This also means slowing the compiler down quite a lot.

Slowing it down will again become no problem, when my new
compiler strategy is ready. The number of compilations
will reduce so drastically, that the slowdown is neglectible.

Yes, I did not give an answer. I have the vague feeling of
three months full-time work. My problem right now is to
ensure that it will become less and not more :-)

cheers - chris
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From ethan at stoneleaf.us  Thu Jul 23 12:42:17 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 23 Jul 2009 09:42:17 -0700
Subject: Changing the private variables content
In-Reply-To: <4A679415.90407@stoneleaf.us>
References: <mailman.13388.1248268320.8014.python-list@python.org>	<4A671BAF.1060204@gmail.com>
	<4A679415.90407@stoneleaf.us>
Message-ID: <4A6892E9.20602@stoneleaf.us>

Or, in other words, what Steven D'Aprano had already said.  Guess I 
should read the whole thread before madly posting!  :)

~Ethan~


From mal at egenix.com  Thu Jul 23 12:56:24 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Thu, 23 Jul 2009 18:56:24 +0200
Subject: Balanced binary tree implementation
In-Reply-To: <4A662E37.6090406@gmail.com>
References: <4A662E37.6090406@gmail.com>
Message-ID: <4A689638.6050303@egenix.com>

Lucas P Melo wrote:
> Hello,
> 
> I would like to use a balanced binary tree implementation (preferably
> within some API).
> Any hints about where I could find it?
> 
> I am looking for something that implements insertion, deletion, search
> and a special search that returns the lesser element bigger than a given
> key [1].
> 
> A nice possibility would be an extensible API that allows me to inherit
> its classes and to add operations myself.
> 
> Thanks in advance.
> 
> [1] Ex: 1 2 3 4 5 6 are elements of the bbt. If I use this operation
> given 4 as the parameter, the value returned would be 5.

You might want to have a look at the btree implementation we
have in mxBeeBase:

    http://www.egenix.com/products/python/mxBase/mxBeeBase/

It's written in C and optimized for on-disk operations.

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 23 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From philip at semanchuk.com  Thu Jul 23 13:01:45 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 13:01:45 -0400
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4314c1f70907230936w51881daaja30e1abf73742ad2@mail.gmail.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
	<CE27720A-C736-4670-AF63-6164A859BA4F@semanchuk.com>
	<4314c1f70907230913t76567a7cm3b3e4649f5bc6e4e@mail.gmail.com>
	<35D1D3C1-ECC3-4FEC-A21E-C6A17D9E22D7@semanchuk.com>
	<4314c1f70907230936w51881daaja30e1abf73742ad2@mail.gmail.com>
Message-ID: <6835BCF7-0B3C-4E5D-B737-57B288D786D3@semanchuk.com>


On Jul 23, 2009, at 12:36 PM, tiefeng wu wrote:

> 2009/7/24 Philip Semanchuk <philip at semanchuk.com>:
>>
>> I know this will sound like a sarcastic comment, but it is sincere:  
>> my
>> suggestion is that if you want to parse C/C++ (or Python, or Perl, or
>> Fortran, etc.), use a real parser, not regexes unless you're  
>> willing to
>> sacrifice some accuracy. Sooner or later you'll come across some  
>> code that
>> your regexes won't handle, like this --
>>
>> #ifdef FOO_BAR
>> #include <this.h>
>> /* #else */
>> #include <that.h>
>> #endif
>>
>>
>> Parsing code is difficult...
>>
> I understand your point, thanks for your suggestion, Philip. And I've
> met the problem like in your example
> The reason I choose regex because I barely know about "real parser",
> for me it still in some "dark area" :)
> But I'll find something to learn.

Yes! Learning is always good. And as I said, if you don't mind missing  
some unusual cases, regexes are fine. I don't know how accurate you  
want your results to be.

As for real parsers, there's lots of them out there, although they may  
be overkill for what you want to do. Here's one written entirely in  
Python:
http://www.dabeaz.com/ply/

Whatever you choose, good luck with it.

Cheers
Philip



From robert.kern at gmail.com  Thu Jul 23 13:03:03 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 23 Jul 2009 12:03:03 -0500
Subject: PyQt GUI
In-Reply-To: <16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
	<mailman.2864.1247095779.8015.python-list@python.org>	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>	<mailman.2902.1247154895.8015.python-list@python.org>	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>
	<16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>
Message-ID: <h4a548$eb6$1@ger.gmane.org>

On 2009-07-23 03:55, Helvin wrote:
> I believe I now have vtkpython.exe. However, my 'import vtk' statement
> in my python code is not working. The error says something like "no
> module named vtk".
> Where do I find modules for vtk in pyqt? Do they exist?

There are no VTK modules in PyQt itself. The PyQt support is in the vtk package 
which can be built with VTK itself. You will need to install VTK and the vtk 
package correctly in order to achieve this. vtkpython.exe is not going to help 
you. Ignore it. After you have built VTK, you need to do an extra step to 
install the vtk package to where your Python interpreter will be able to find it.

Let's say that your build directory is c:\vtkbuild.

   cd \vtkbuild\Wrapping\Python
   python setup.py install
   cd \

Now you should be able to import vtk from your normal Python interpreter. If you 
are still having problems, you will need to copy-and-paste exactly what you did 
and what error messages you got. Do not paraphrase error messages.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dwbear75 at gmail.com  Thu Jul 23 13:06:35 2009
From: dwbear75 at gmail.com (DwBear75)
Date: Thu, 23 Jul 2009 10:06:35 -0700 (PDT)
Subject: installing 2.6 on vista64
Message-ID: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>

I just downloaded and attempted to install python 2.6.2.  The
installer proceeds to do its work then dies, leaving an entry in the
eventlog:

Windows Installer installed the product. Product Name: Python 2.6.2.
Product Version: 2.6.2150. Product Language: 1033. Installation
success or error status: 1602.

Googling for this I wasn't able to narrow the results down to
something usable. Anyone know of issues and how to fix them installing
on vista 64 (yes, I have 8 gigs of ram)


From tismer at stackless.com  Thu Jul 23 13:06:43 2009
From: tismer at stackless.com (Christian Tismer)
Date: Thu, 23 Jul 2009 10:06:43 -0700
Subject: ANN: psyco V2
In-Reply-To: <639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
Message-ID: <4A6898A3.3060609@stackless.com>

On 7/17/09 4:11 AM, Bearophile wrote:
> Very good, thank you. I'll try it when I can.
>
> Is Psyco3 going to borrow/steal some ideas/code from Unladen Swallow?

Psyco3: nice typo! :-)

Well, I haven't so far found a new idea there that I'd want
to borrow and did not know from PyPy, before.
Wasn't the project plan saying the opposite, borrowing
some ideas from psyco? :-)
http://code.google.com/p/unladen-swallow/wiki/ProjectPlan

> The problem I have with Psyco1.6 is that you can't use the normal
> profilers to know how much seconds of running time is taken by each
> function/method of your code.

Yes, the profiler hooks are not useful with psyco. You need
to write extra functions for timing, as we do in the benchmark
directory.

> Psyco1.6 has a profile() function, but I am not much able to use it
> yet.

The profile() function is used for profile driven compilation,
as opposed to psyco.full(). This will go away, pretty soon.
Psyco will only be switched on or off.

Maybe I will add an option for profiling the compiled code.
Interesting idea!

cheers - chris

-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From leerisq at gmail.com  Thu Jul 23 13:07:05 2009
From: leerisq at gmail.com (LeeRisq)
Date: Thu, 23 Jul 2009 10:07:05 -0700 (PDT)
Subject: win32clipboard operation
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
	<mailman.3601.1248365085.8015.python-list@python.org>
Message-ID: <b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>

On Jul 23, 9:05?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> LeeRisq wrote:
> > Hi all,
>
> > Newbie question. I've written a script that outputs to a text file.
>
> > Now, I just want to copy the content to win32clipboard for access to
> > other applications. Here's the mess I've come up with so far:)
>
> [snip]
>
> def copy_text():
> ? ? ?ifile = open(r"C:\Query\DQL.txt", "r")
> ? ? ?text = ifile.read()
> ? ? ?ifile.close()
>
> ? ? ?win32clipboard.OpenClipboard()
> ? ? ?win32clipboard.EmptyClipboard()
> ? ? ?win32clipboard.SetClipboardText(text)
> ? ? ?win32clipboard.CloseClipboard()

I've actually tried this configuration, but I did it again just to be
sure. The program executes without exception, but the text still isn't
copied to the clipboard. Any ideas?


From robert.kern at gmail.com  Thu Jul 23 13:09:55 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 23 Jul 2009 12:09:55 -0500
Subject: import vs imp and friends.
In-Reply-To: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
References: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
Message-ID: <h4a5h4$eb6$3@ger.gmane.org>

On 2009-07-23 09:44, Emanuele D'Arrigo wrote:
> Greetings,
>
> I was looking in the archive of this newsgroup and I found this
> snippet:
>
> import imp
> sourcecode = 'def foo(x): return 11*x'
> mod = imp.new_module('foo')
> exec sourcecode in mod.__dict__
> mod.foo(16)
>
> Together with similar and sometimes more complete snippets available
> they show how a module can be created out of string, plain text files
> and compiled files. Neat!
>
> Now the question. Apart from checking sys.module first and eventually
> adding the new module to it if it isn't there already, and apart from
> setting __file__, is there anything else that import does and this
> snippet doesn't?

Brett Cannon has a good presentation that covers basically the entirety of the 
import mechanism:

http://us.pycon.org/2008/conference/schedule/event/12/

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From igouy2 at yahoo.com  Thu Jul 23 13:15:00 2009
From: igouy2 at yahoo.com (Isaac Gouy)
Date: Thu, 23 Jul 2009 10:15:00 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
Message-ID: <72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>

On Jul 21, 10:09?pm, Raffael Cavallaro
<raffaelcavall... at pas.espam.s.il.vous.plait.mac.com> wrote:
> On 2009-07-21 19:06:02 -0400, Neil Hodgson
> <nyamatongwe+thun... at gmail.com> said:
>
> > ? ?Python uses native threads.
>
> So it can be teh-slowness on all ur cores!
>
> <http://shootout.alioth.debian.org/u64q/benchmark.php?test=nbody?=all>
>
> The global interpreter lock doesn't help much either.


As you've linked to programs that /have not/ been written to use
threading or multiple cores (look at the "~ CPU Load" column) I get
the feeling I'm missing the joke?





From breamoreboy at yahoo.co.uk  Thu Jul 23 13:21:59 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Thu, 23 Jul 2009 18:21:59 +0100
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
Message-ID: <h4a667$hur$1@ger.gmane.org>

Phillip B Oldham wrote:
> My colleagues and I have been working with python for around 6 months
> now, and while we love a lot of what python has done for us and what
> it enables us to do some of the decisions behind such certain
> data-types and their related methods baffle us slightly (when compared
> to the decisions made in other, similarly powerful languages).
> 
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
> 

[rest of original snipped as already discussed]

Sorry if this has been discussed and I've missed it, but how about 
memory allocation.  An immutable tuple has a fixed memory allocation 
whereas that for the mutable list must be liable to change.  You might 
like to look at the recent thread on this ng 'List insertion cost' and 
follow the links to Raymond Hettinger's power point presentation.

Kindest regards.

Mark Lawrence.



From piet at cs.uu.nl  Thu Jul 23 13:25:48 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 19:25:48 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl> <1248342610.3698.7.camel@krishna-laptop>
	<h49ine$cs8$1@ger.gmane.org>
	<mailman.3583.1248352321.8015.python-list@python.org>
Message-ID: <m2d47rjopv.fsf@cs.uu.nl>

>>>>> Krishnakant <hackingkk at gmail.com> (K) wrote:

>K> On Thu, 2009-07-23 at 13:50 +0200, paul wrote:
>>> If the user running python program is allowed to call setuid() then yes.
>>> 
>K> NO, i don't think i can do that.  I am getting opperation not permitted.

>K> Any ways I think probably subprocess will have to sort it out.

>>> Did you try running "sudo -u postgres blabla" with subprocess?
>>> 
>K> Yes, but still not got the intended result which is now obvious.
>>> > 2. now execute the python code for connecting to the postgresql
>>> > database.
>>> > In the second point I actually want to execute python code not shell
>>> > level command so will the sudo -u in the subprocess.Popen change the
>>> > user in the script?
>>> No, as the name "subprocess" suggests you are spawning a new process 
>>> which gets another uid through sudo. This does not affect the parent 
>>> process.
>>> 
>K> Ok then here is the work-around which I am thinking to try, Plese tell
>K> me if it is correct.
>K> I will let that subprocess start python inthe background and execute the
>K> connecting code to postgresql including importing the pygresql library.
>K> Then I will create the connection and cursor objcts in that subprocess.
>K> But my concern is, will the connection object in the child process
>K> (subprocess) be available to the parrent process?

No. However it is still not clear why you want to run under the postgres
user id. Why can't the original process not do the postgres connection?

If that is really impossible, then you might start the new process with
sudo and let it do a socket tunnelling to postgress, i.e. make a
connection to the postgres server and a socket connection to the
original Python script, and copy everything from one socket to the other
- in both directions. However this can also be done with a ssh tunnel
which might be simpler.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at mrabarnett.plus.com  Thu Jul 23 13:42:21 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 18:42:21 +0100
Subject: win32clipboard operation
In-Reply-To: <b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>	<mailman.3601.1248365085.8015.python-list@python.org>
	<b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>
Message-ID: <4A68A0FD.4010204@mrabarnett.plus.com>

LeeRisq wrote:
> On Jul 23, 9:05 am, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> LeeRisq wrote:
>>> Hi all,
>>> Newbie question. I've written a script that outputs to a text file.
>>> Now, I just want to copy the content to win32clipboard for access to
>>> other applications. Here's the mess I've come up with so far:)
>> [snip]
>>
>> def copy_text():
>>      ifile = open(r"C:\Query\DQL.txt", "r")
>>      text = ifile.read()
>>      ifile.close()
>>
>>      win32clipboard.OpenClipboard()
>>      win32clipboard.EmptyClipboard()
>>      win32clipboard.SetClipboardText(text)
>>      win32clipboard.CloseClipboard()
> 
> I've actually tried this configuration, but I did it again just to be
> sure. The program executes without exception, but the text still isn't
> copied to the clipboard. Any ideas?

All I can say is that it works for me (Windows XP Pro, service pack 3).


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Thu Jul 23 13:45:52 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Thu, 23 Jul 2009 13:45:52 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
Message-ID: <h4a7kg$q36$1@news.eternal-september.org>

On 2009-07-23 13:15:00 -0400, Isaac Gouy <igouy2 at yahoo.com> said:

> I get
> the feeling I'm missing the joke?

Yes, you are missing the joke. The point is that if python is 60x 
slower than C, even if there were not a GIL, it would require running 
the python program on a 60 core machine just reach parity with C. The 
existence of the GIL means that in reality you'd probably need a 
several hundred core machine running python just to equal what C can do 
on one core. Hence the 13375p34k pseudo quote - "teh slowness on all ur 
cores!"
-- 
Raffael Cavallaro



From alex.repenning at gmail.com  Thu Jul 23 13:54:26 2009
From: alex.repenning at gmail.com (game_designer)
Date: Thu, 23 Jul 2009 10:54:26 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org> 
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
Message-ID: <c978ad4e-16ce-4a5e-a361-7a17f92be12c@12g2000pri.googlegroups.com>

Perhaps like Xah Lee I find, after many years of Lisp programming,
these discussions increasingly frustrating and even, in some sense,
amazing. We can speculate all we want about syntax and semantics of
programing languages. What counts in the end are really the PRAGMATICS
of programming languages. How can I do something with a language that
is USEFUL to me? Will the result be good looking, and snappy or some
ugly, dated looking, crashing application? For instance, last time I
played with Scheme (drScheme) to explore some OpenGL 3D issue I was
not impressed at all. One can debate the syntax and semantics of
Scheme but in that particular instance all that was important to me
was the fact that the Scheme example performed terrible and the
threading fell completely apart when running more that a single OpenGL
window. Perhaps this was coded poorly but I don't care. Scheme left a
pretty bad impression.


alex

Prof. Alexander Repenning

University of Colorado
Computer Science Department
Boulder, CO 80309-430


From piet at cs.uu.nl  Thu Jul 23 14:20:50 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 20:20:50 +0200
Subject: sqlite3 performance problems only in python
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<mailman.3586.1248354168.8015.python-list@python.org>
Message-ID: <m28wifjm65.fsf@cs.uu.nl>

>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:

>SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>SM>  from OPNAMEN
>SM>    inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>SM>    inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>SM>    inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>SM>    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>SM>    inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>SM> POID_SSID_SCID.POID ) and
>SM>                                     ( SUBSCHAAL_GEGEVENS.SSID =
>SM> POID_SSID_SCID.SSID )
>SM>    inner join SCORES             on SCORES.SCID             =
>SM> POID_SSID_SCID.SCID
>SM>    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>SM>    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>SM>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>SM>    and lower ( NAME_ ) = 'fatigue'
>SM>    and TEST_COUNT in (3,4)
>SM>    and DATETIME > 39814.0
>SM>    and SCORE < 30

1) Do you have indices on the join fields?
2) Look at the ANALYZE command
3) Look at the EXPLAIN command
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From paul-donnelly at sbcglobal.net  Thu Jul 23 15:09:31 2009
From: paul-donnelly at sbcglobal.net (Paul Donnelly)
Date: Thu, 23 Jul 2009 14:09:31 -0500
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
	<c978ad4e-16ce-4a5e-a361-7a17f92be12c@12g2000pri.googlegroups.com>
Message-ID: <87r5w72p3o.fsf@plap.localdomain>

game_designer <alex.repenning at gmail.com> writes:

> Perhaps like Xah Lee I find, after many years of Lisp programming,
> these discussions increasingly frustrating and even, in some sense,
> amazing. We can speculate all we want about syntax and semantics of
> programing languages. What counts in the end are really the PRAGMATICS
> of programming languages. How can I do something with a language that
> is USEFUL to me? Will the result be good looking, and snappy or some
> ugly, dated looking, crashing application? For instance, last time I
> played with Scheme (drScheme) to explore some OpenGL 3D issue I was
> not impressed at all. One can debate the syntax and semantics of
> Scheme but in that particular instance all that was important to me
> was the fact that the Scheme example performed terrible and the
> threading fell completely apart when running more that a single OpenGL
> window. Perhaps this was coded poorly but I don't care. Scheme left a
> pretty bad impression.

One implementation of one dialect of Lisp worked poorly for one
particular project some unspecified number of years ago, judging by code
(written by you, no less) that may or may not have been terrible? I
appreciate that this was a frustrating experience, but I don't see what
lesson about Lisp programming we're supposed to be getting from this.


From bbarbero at inescporto.pt  Thu Jul 23 15:23:54 2009
From: bbarbero at inescporto.pt (bbarbero at inescporto.pt)
Date: Thu, 23 Jul 2009 21:23:54 +0200
Subject: Problems in commands.getoutput(cmd) with sox
Message-ID: <20090723212354.5378695qs4beje8a@horde.inescporto.pt>

Hello to all!

I am a new researcher, new to Python as well, and I have a problem,  
when I try to get commands from sox in a python script. I am going  
crazy, because this code has been working before.. so I dont really  
know whats going on..

Ive already seen some solutions that match with what I have. I am  
running this:



         if os.path.splitext(file_au)[1] == ".au":
           	resampled_file_path = os.path.join(resampled_path, file_au)
            	cmd = "sox " + dir_file + " -r 44100 " + resampled_file_path
            	print cmd
		output = commands.getoutput(cmd)
		print output

What i do, is just to resample a song from dir_file to  
resampled_file_path. As a result of "cmd" I get:

....
sox /Volumes/HAL/Datasets/Audio/gtzan_genres/rock/rock.00097.au -r  
44100  
/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resampled/rock/rock.00097.au
.....

If I run this on the command line, it will work perfectly!

But The program stops at

  File  
"/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resamplingto44.py",  
line 35
     output = commands.getoutput(cmd)
     ^
IndentationError: unexpected indent

I dont have any idea, whats going on, I am trying lot of things, but I  
can understand where is the error as it has been running perfectly  
before.

Any suggestions will be more than welcome! Thanks in advance for your help!

Best regards,
Beatriz Mora.



----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.


From nick at craig-wood.com  Thu Jul 23 15:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 14:29:57 -0500
Subject: extract c/cpp include file with regular expression
References: <mailman.3597.1248363967.8015.python-list@python.org>
Message-ID: <slrnh6he16.dgi.nick@irishsea.home.craig-wood.com>

tiefeng wu <icebergwtf at gmail.com> wrote:
>  I need to parse c/cpp source files, one requirement is to extract
>  included header file name.

If you are serious about parsing C code then you'll want to
investigate gcc-xml

http://www.gccxml.org/HTML/Index.html

This runs the gcc frontend over the code but instead of producing an
object file, it produces a machine readable xml file describing the
source.

It is used by h2xml.py / xml2py.py to make ctypes header file
automatically.

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From gslindstrom at gmail.com  Thu Jul 23 15:30:09 2009
From: gslindstrom at gmail.com (Greg Lindstrom)
Date: Thu, 23 Jul 2009 14:30:09 -0500
Subject: Creating xml
Message-ID: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>

It's been a while since I've played with XML using Python but I've been
asked to create XML using data from our postgres database.  Currently we are
generating XML directly from the database using a set of stored procedures
but it is too slow (yes, I have numbers).  I have been asked to create a
routine to generate the XML to see if it will be faster that the sprocs
(which I think it will be, based on other routines we have running).  But I
digress...

Using my favorite search engine I see that there is a lot of material on
Python and XML.  At the risk of starting something (which is not my
intention), what are my options if I want to create xml?  Ceratinly writing
my own routine is an option, but I bet there are better ones :-)

How about if I need/want to parse or process an XML file?

Thanks!

--greg
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/5730595d/attachment.html>

From piet at cs.uu.nl  Thu Jul 23 15:30:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 21:30:56 +0200
Subject: Looking for os.listdir() generator
References: <mailman.3584.1248352640.8015.python-list@python.org>
Message-ID: <m24ot3jixb.fsf@cs.uu.nl>

>>>>> Christian Heimes <lists at cheimes.de> (CH) wrote:

>CH> Hello,
>CH> I'm looking for a generator version of os.listdir() for Python 2.5 and
>CH> newer. I know somebody has worked on it because I've seen a generator
>CH> version in a posting on some list or blog a while ago. I can't find it
>CH> anymore. It seems my Google fu is lacking today. All I can find is a
>CH> very old version of xlistdir. A Cython based solution is appreciated but
>CH> please no ctypes version.

Nick Craig-Wood <nick at craig-wood.com> posted these about 5 weeks ago in
the thread `waling a directory with very many files' [sic!]

Message id's: 
<slrnh3c0r8.7rv.nick at irishsea.home.craig-wood.com> (ctypes)
<slrnh3fvbp.3pv.nick at irishsea.home.craig-wood.com> (Cython)

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From leerisq at gmail.com  Thu Jul 23 15:31:14 2009
From: leerisq at gmail.com (LeeRisq)
Date: Thu, 23 Jul 2009 12:31:14 -0700 (PDT)
Subject: win32clipboard operation
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
	<mailman.3601.1248365085.8015.python-list@python.org>
	<b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>
Message-ID: <b6ed7465-b9e0-42a2-8a5f-d2eeae358c03@j32g2000yqh.googlegroups.com>

> I've actually tried this configuration, but I did it again just to be
> sure. The program executes without exception, but the text still isn't
> copied to the clipboard. Any ideas?

So, I think I've figured out the issue. Which brings me to another
question...why is it that I can manually copy and paste the text
without issue, but when I run a python script that copies the same
text to the clipboard, it won't accept the amount of text I am placing
on the clipboard. Is there some kind of setting I am missing? Buffer
size maybe?



From clp2 at rebertia.com  Thu Jul 23 15:32:58 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 23 Jul 2009 12:32:58 -0700
Subject: Creating xml
In-Reply-To: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
References: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
Message-ID: <50697b2c0907231232o4e5614dame0adee88d4a15cf@mail.gmail.com>

On Thu, Jul 23, 2009 at 12:30 PM, Greg Lindstrom<gslindstrom at gmail.com> wrote:
<snip>
> How about if I need/want to parse or process an XML file?

xml.etree.ElementTree in the standard library:
http://docs.python.org/library/xml.etree.elementtree.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From vinay_sajip at yahoo.co.uk  Thu Jul 23 15:42:29 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Thu, 23 Jul 2009 12:42:29 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
Message-ID: <2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>

On Jul 23, 4:06 am, Naoki INADA <songofaca... at gmail.com> wrote:
> In document <http://docs.python.org/library/
> stdtypes.html#file.encoding>:
>
> >> The encoding that this file uses. When Unicode strings are written to a file,
> >>  they will be converted to byte strings using this encoding. In addition,
> >> when the file is connected to a terminal, the attribute gives the encoding
> >> that the terminal is likely to use
>
> But inlogging.StreamHandler.emit() ::
>
>                 try:
>                     if (isinstance(msg, unicode) and
>                         getattr(stream, 'encoding', None)):
>                         #fs = fs.decode(stream.encoding)
>                         try:
>                             stream.write(fs % msg)
>                         except UnicodeEncodeError:
>                             #Printing to terminals sometimes fails.
> For example,
>                             #with an encoding of 'cp1251', the above
> write will
>                             #work if written to a stream opened or
> wrapped by
>                             #the codecs module, but fail when writing
> to a
>                             #terminal even when the codepage is set to
> cp1251.
>                             #An extra encoding step seems to be
> needed.
>                             stream.write((fs % msg).encode
> (stream.encoding))
>                     else:
>                         stream.write(fs % msg)
>                 except UnicodeError:
>                     stream.write(fs % msg.encode("UTF-8"))
>
> And behavior of sys.stdout in Windows::>>> import sys
> >>> sys.stdout.encoding
> 'cp932'
> >>> u = u"???"
> >>> u
>
> u'\u3042\u3044\u3046'>>> print >>sys.stdout, u
> ???
> >>> sys.stderr.write(u)
>
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> UnicodeEncodeError: 'ascii' codec can't encode characters in position
> 0-2: ordinal not in range(128)
>
> What is file.encoding convention?
> If I want to write a unicode string to a file(-like) that have
> encoding attribute, I should do
> (1) try: file.write(unicode_str),
> (2) except UnicodeEncodeError: file.write(unicode_str.encode
> (file.encoding))
> likelogging?
> It seems agly.

Further to my earlier mail, please have a look at the following
screenshot:

http://imgur.com/FtAi0.png

As you can see, the codepage is set to 1251 (Cyrillic) at the
beginning. A Unicode string is initialised with Cyrillic code points.
Then sys.stdout.encoding shows 'cp1251', but writing the string to it
gives a UnicodeEncodeError. Explicitly encoding the string and writing
it works. Next, we get a wrapper from the codecs module for the same
encoding and use it to wrap sys.stdout. Writing the Unicode string to
the wrapped string works, too.

So the problem is essentially this: if a stream has an encoding
attribute, sometimes it is a wrapped stream which encodes Unicode
(e.g. a stream obtained via the codecs module) and sometimes it is not
(e.g. sys.stdout, sys.stderr).

Regards,

Vinay


From clp2 at rebertia.com  Thu Jul 23 15:52:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 23 Jul 2009 12:52:48 -0700
Subject: effbot.org broken (WAS: Problems in commands.getoutput(cmd) with sox)
Message-ID: <50697b2c0907231252w4715c94di7876b8580cddf170@mail.gmail.com>

On Thu, Jul 23, 2009 at 12:42 PM, Chris Rebert<clp2 at rebertia.com> wrote:
> You can use tabnanny to help diagnose the problem:
> http://74.125.155.132/search?q=cache:QtxvZm3QDLsJ:effbot.org/librarybook/tabnanny.htm+tabnanny&cd=3&hl=en&ct=clnk&gl=us&client=firefox-a

Anyone know what's the deal with effbot.org? It seems to be broken at
present, forcing me to use Google's cached version.
It's a real shame since it has lots of handy Python info.

Cheers,
Chris
-- 
http://blog.rebertia.com


From stef.mientki at gmail.com  Thu Jul 23 15:58:30 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 21:58:30 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <m28wifjm65.fsf@cs.uu.nl>
References: <4A684B56.3020906@gmail.com>
	<4A685A12.4080800@tim.thechases.com>	<mailman.3586.1248354168.8015.python-list@python.org>
	<m28wifjm65.fsf@cs.uu.nl>
Message-ID: <4A68C0E6.90905@gmail.com>

Piet van Oostrum wrote:
>>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:
>>>>>>             
>
>   
>> SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>> SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>> SM>  from OPNAMEN
>> SM>    inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>> SM>    inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>> SM>    inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>> SM>    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>> SM>    inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>> SM> POID_SSID_SCID.POID ) and
>> SM>                                     ( SUBSCHAAL_GEGEVENS.SSID =
>> SM> POID_SSID_SCID.SSID )
>> SM>    inner join SCORES             on SCORES.SCID             =
>> SM> POID_SSID_SCID.SCID
>> SM>    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>> SM>    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>> SM>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>> SM>    and lower ( NAME_ ) = 'fatigue'
>> SM>    and TEST_COUNT in (3,4)
>> SM>    and DATETIME > 39814.0
>> SM>    and SCORE < 30
>>     
>
> 1) Do you have indices on the join fields?
>   
well I'm happily surprised, you came up with this suggestion
- I thought that sqlite created indexes on all primairy key and unique 
fields
- but after explicitly creating the indices, a gained a speed of about a 
factor 10
After checking the database creation, it seemed I forgot to make these 
fields the primary key
so thanks very much.

I gained another factor of 10 speed by updating to version 2.5.5 of 
pysqlite.

cheers,
Stef
> 2) Look at the ANALYZE command
> 3) Look at the EXPLAIN command
>   



From stef.mientki at gmail.com  Thu Jul 23 16:01:16 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 22:01:16 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <de32cc030907230909u35979708seb76c7193b31105@mail.gmail.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>	
	<4A685F75.10701@gmail.com>
	<de32cc030907230909u35979708seb76c7193b31105@mail.gmail.com>
Message-ID: <4A68C18C.3090605@gmail.com>

David Stanek wrote:
> On Thu, Jul 23, 2009 at 9:02 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
>   
>> btw, I don't know if it's of any importance, the SQL-statement I perform is
>> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>>  from OPNAMEN
>>   inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>>   inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>>   inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>>   inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>>   inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>> POID_SSID_SCID.POID ) and
>>                                    ( SUBSCHAAL_GEGEVENS.SSID =
>> POID_SSID_SCID.SSID )
>>   inner join SCORES             on SCORES.SCID             =
>> POID_SSID_SCID.SCID
>>   inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>>   inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>>   and lower ( NAME_ ) = 'fatigue'
>>   and TEST_COUNT in (3,4)
>>   and DATETIME > 39814.0
>>   and SCORE < 30
>>     
>
> Warning: I suck at SQL and hate it with a passion...
>   
+1,
but I couldn't find anything better.
I guess you have some better suggestions ?
(I looked at Dee, but from my first view, it looks a bit premature)

thanks,
Stef



From nick at craig-wood.com  Thu Jul 23 16:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 15:29:57 -0500
Subject: sqlite3 performance problems only in python
References: <4A684B56.3020906@gmail.com>
	<4A685A12.4080800@tim.thechases.com> <4A685F75.10701@gmail.com>
	<mailman.3602.1248365399.8015.python-list@python.org>
Message-ID: <slrnh6heht.dgi.nick@irishsea.home.craig-wood.com>

David Stanek <dstanek at dstanek.com> wrote:
>  On Thu, Jul 23, 2009 at 9:02 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
> >
> > btw, I don't know if it's of any importance, the SQL-statement I perform is
> > select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
> > ?from OPNAMEN
> > ? inner join POID_VLID ? ? ? ? ?on OPNAMEN.POID ? ? ? ? ? ?= POID_VLID.POID
> > ? inner join VRAAGLST ? ? ? ? ? on VRAAGLST.VLID ? ? ? ? ? = POID_VLID.VLID
> > ? inner join VLID_SSID ? ? ? ? ?on VRAAGLST.VLID ? ? ? ? ? = VLID_SSID.VLID
> > ? inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
> > ? inner join POID_SSID_SCID ? ? on ( OPNAMEN.POID ? ? ? ? ? ?=
> > POID_SSID_SCID.POID ) and
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?( SUBSCHAAL_GEGEVENS.SSID =
> > POID_SSID_SCID.SSID )
> > ? inner join SCORES ? ? ? ? ? ? on SCORES.SCID ? ? ? ? ? ? =
> > POID_SSID_SCID.SCID
> > ? inner join PID_POID ? ? ? ? ? on OPNAMEN.POID ? ? ? ? ? ?= PID_POID.POID
> > ? inner join PATIENT ? ? ? ? ? ?on PATIENT.PID ? ? ? ? ? ? = PID_POID.PID
> > ?where substr ( lower( NAME) , 1, 6) ?= 'cis20r'
> > ? and lower ( NAME_ ) = 'fatigue'
> > ? and TEST_COUNT in (3,4)
> > ? and DATETIME > 39814.0
> > ? and SCORE < 30
> 
>  Warning: I suck at SQL and hate it with a passion...
> 
>  By using lower() on the left side of the where expressions I believe
>  that you are table scanning. So it is not the size of the data
>  returned, but the size of the data that needs to be scanned.

In all the databases I've used, the like operator has been case
insensitive, so if that is the problem you could use

  NAME like '%cis20r%'  -- not quite the same, but close!
  and NAME_ like 'fatigue'

instead which might be quicker.  Or not ;-)

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From nick at craig-wood.com  Thu Jul 23 16:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 15:29:57 -0500
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system()
	that  doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <slrnh6hfrp.dgi.nick@irishsea.home.craig-wood.com>

Ville Vainio <vivainio at gmail.com> wrote:
>  Has anyone implementing something like what the subject line
>  indicates?
> 
>  The idea:
> 
>  To run functions that execute a series of system commands without
>  blocking the ui, *and* without adding state machine logic.
> 
>  The syntax would be something like:
> 
>  def work():
> 
>    showstatus("building")
>    r = yield runshell("make")
>    showstatus("installing")
>    r = yield runshell("make install")
>    showstatus("Success")
> 
>  mygui.startwork(work)
>  # returns immediately, runs work() gradually in the background.
> 
>  The catch is that showstatus() would need to be run in the mainloop,
>  so running the whole thing in a thread is a no-go.
> 
>  I imagine runshell() would be implemented in terms of QProcess, or
>  subprocess.Popen/os.system and a worker thread.
> 
>  Anyone done this already, or do I have to roll my own?

You might want to look at twisted, in particular

  http://twistedmatrix.com/trac/wiki/DeferredGenerator

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From nick at craig-wood.com  Thu Jul 23 16:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 15:29:57 -0500
Subject: Looking for os.listdir() generator
References: <mailman.3584.1248352640.8015.python-list@python.org>
Message-ID: <slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>

Christian Heimes <lists at cheimes.de> wrote:
>  I'm looking for a generator version of os.listdir() for Python 2.5 and
>  newer. I know somebody has worked on it because I've seen a generator
>  version in a posting on some list or blog a while ago. I can't find it
>  anymore. It seems my Google fu is lacking today. All I can find is a
>  very old version of xlistdir. A Cython based solution is appreciated but
>  please no ctypes version.

I posted exactly that yesterday I think ;-)

Note that this has a python part as well as a ctypes part because the
version of ctypes I used doesn't support generators.  I think the
development version does though.

Here is it

--setup.py----------------------------------------------------------

from distutils.core import setup
from distutils.extension import Extension
from Cython.Distutils import build_ext

setup(
    cmdclass = {'build_ext': build_ext},
    ext_modules = [Extension("directory", ["directory.pyx"])]
)

--directory.pyx----------------------------------------------------------

# Cython interface for listdir
# python setup.py build_ext --inplace

import cython

cdef extern from "dirent.h":
    struct dirent:
        char d_name[0]
    ctypedef struct DIR
    DIR *opendir(char *name)
    int closedir(DIR *dirp)
    dirent *readdir(DIR *dirp)

cdef extern from "errno.h":
    int errno

cdef extern from "string.h":
    char *strerror(int errnum)

cdef class Directory:
    """Represents an open directory"""
    
    cdef DIR *handle

    def __init__(self, path):
        self.handle = opendir(path)
        if self.handle is NULL:
            raise OSError(errno, "Failed to open directory: %s" % strerror(errno))

    def readdir(self):
        """Read the next name in the directory"""
        cdef dirent *p
        p = readdir(self.handle)
        if p is NULL:
            return None
        return p.d_name

    def close(self):
        """Close the directory"""
        if self.handle is not NULL:
            closedir(self.handle)
            self.handle = NULL

    def __dealloc__(self):
        self.close()

--listdir.py----------------------------------------------------------

from directory import Directory

def listdir(path):
    """
    A generator to return the names of files in the directory passed in
    """
    d = Directory(path)
    while True:
        name = d.readdir()
        if not name:
            break
        if name not in (".", ".."):
            yield name
    d.close()
    del d

if __name__ == "__main__":
    import sys
    paths = sys.argv[1:]
    if not paths:
        paths = ["."]
    for path in paths:
        print "*** %s ***" % path
        for name in listdir(path):
            print name

------------------------------------------------------------

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From jaime.frio at gmail.com  Thu Jul 23 16:34:21 2009
From: jaime.frio at gmail.com (Jaime Fernandez del Rio)
Date: Thu, 23 Jul 2009 22:34:21 +0200
Subject: installing 2.6 on vista64
In-Reply-To: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
References: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
Message-ID: <97a8f1a70907231334y1fd64890g9c8cee11b1e41f8f@mail.gmail.com>

I have installed the 32 bit 2.6 and the 64 bit 3.1 on my machine
running Vista 64 without any issues.

Which of course has nothing to do with your problem....

On Thu, Jul 23, 2009 at 7:06 PM, DwBear75<dwbear75 at gmail.com> wrote:
> I just downloaded and attempted to install python 2.6.2. ?The
> installer proceeds to do its work then dies, leaving an entry in the
> eventlog:
>
> Windows Installer installed the product. Product Name: Python 2.6.2.
> Product Version: 2.6.2150. Product Language: 1033. Installation
> success or error status: 1602.
>
> Googling for this I wasn't able to narrow the results down to
> something usable. Anyone know of issues and how to fix them installing
> on vista 64 (yes, I have 8 gigs of ram)
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
(\__/)
( O.o)
( > <) Este es Conejo. Copia a Conejo en tu firma y ay?dale en sus
planes de dominaci?n mundial.


From malaclypse2 at gmail.com  Thu Jul 23 16:50:56 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Thu, 23 Jul 2009 16:50:56 -0400
Subject: sqlite3 performance problems only in python
In-Reply-To: <slrnh6heht.dgi.nick@irishsea.home.craig-wood.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<4A685F75.10701@gmail.com>
	<mailman.3602.1248365399.8015.python-list@python.org>
	<slrnh6heht.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <16651e80907231350t554f8603i7e6bb82172169b52@mail.gmail.com>

On Thu, Jul 23, 2009 at 4:29 PM, Nick Craig-Wood<nick at craig-wood.com> wrote:
> In all the databases I've used, the like operator has been case
> insensitive, so if that is the problem you could use

This is not true in all databases! ?Many times, this is something that
is configurable when setting up the database server. ?I'm not sure
what the defaults are, but here at work we have DB/2 and Oracle
servers that are case sensitive, and at least one MSSQL server that is
not.

-- 
Jerry


From laran.evans at gmail.com  Thu Jul 23 16:53:19 2009
From: laran.evans at gmail.com (Laran Evans)
Date: Thu, 23 Jul 2009 13:53:19 -0700 (PDT)
Subject: 2.3 missing on OSX
Message-ID: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>

I just tried to run MacVim on OSX 10.5. It crashed with this:

Dyld Error Message:
  Library not loaded: /System/Library/Frameworks/Python.framework/
Versions/2.3/Python
  Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
MacVim.app/Contents/MacOS/Vim
  Reason: image not found

I posted to the MacVim mailing list and was told that that version of
2.3 should always be available because it comes with the OS.

I don't remember if I removed it for whatever reason at some point or
something. In any case, I have python installed now via MacPorts. I
have version 2.3 and 2.5 both installed.

So my question is, is there a way for me to fix the issue by re-
instating the default 2.3 location or something?

I'm not much of a Python person. So I don't really know where to start
with this one.

Thanks.


From deets at nospam.web.de  Thu Jul 23 17:01:21 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 23:01:21 +0200
Subject: 2.3 missing on OSX
In-Reply-To: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
Message-ID: <7cs1d1F1tbs10U1@mid.uni-berlin.de>

Laran Evans schrieb:
> I just tried to run MacVim on OSX 10.5. It crashed with this:
> 
> Dyld Error Message:
>   Library not loaded: /System/Library/Frameworks/Python.framework/
> Versions/2.3/Python
>   Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
> MacVim.app/Contents/MacOS/Vim
>   Reason: image not found
> 
> I posted to the MacVim mailing list and was told that that version of
> 2.3 should always be available because it comes with the OS.

On my 10.5 machine, it is under the above given path.

> 
> I don't remember if I removed it for whatever reason at some point or
> something. In any case, I have python installed now via MacPorts. I
> have version 2.3 and 2.5 both installed.
> 
> So my question is, is there a way for me to fix the issue by re-
> instating the default 2.3 location or something?

Most probably yes, but not using MacPorts. Those aren't 
framework-builds, and not in the proper location anyway.

I suggest you try & get hold of a copy from another OSX-machine (match 
teh architecture), and just copy it into the needed location.

Diez


From philip at semanchuk.com  Thu Jul 23 17:03:41 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 17:03:41 -0400
Subject: 2.3 missing on OSX
In-Reply-To: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
Message-ID: <FDCC09F2-8423-47F4-A3A0-370CF6249C76@semanchuk.com>


On Jul 23, 2009, at 4:53 PM, Laran Evans wrote:

> I just tried to run MacVim on OSX 10.5. It crashed with this:
>
> Dyld Error Message:
>  Library not loaded: /System/Library/Frameworks/Python.framework/
> Versions/2.3/Python
>  Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
> MacVim.app/Contents/MacOS/Vim
>  Reason: image not found
>
> I posted to the MacVim mailing list and was told that that version of
> 2.3 should always be available because it comes with the OS.

OS X 10.4 shipped with Python 2.3 as the system Python.

OS X 10.5 ships with Python 2.5 as the system Python. 2.3 is not  
available unless you install it yourself. And if you install it  
yourself, I wouldn't put it where MacVim is looking for it because the  
System folder is OS X stuff. If MacVim (or any app) contains a  
hardcoded reference to /System/.../2.3/Python, then it will break on  
OS X 10.5.




From philip at semanchuk.com  Thu Jul 23 17:14:37 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 17:14:37 -0400
Subject: 2.3 missing on OSX
In-Reply-To: <7cs1d1F1tbs10U1@mid.uni-berlin.de>
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
	<7cs1d1F1tbs10U1@mid.uni-berlin.de>
Message-ID: <D36FE426-E50F-4452-BACB-0C0100109F58@semanchuk.com>


On Jul 23, 2009, at 5:01 PM, Diez B. Roggisch wrote:

> Laran Evans schrieb:
>> I just tried to run MacVim on OSX 10.5. It crashed with this:
>> Dyld Error Message:
>>  Library not loaded: /System/Library/Frameworks/Python.framework/
>> Versions/2.3/Python
>>  Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
>> MacVim.app/Contents/MacOS/Vim
>>  Reason: image not found
>> I posted to the MacVim mailing list and was told that that version of
>> 2.3 should always be available because it comes with the OS.
>
> On my 10.5 machine, it is under the above given path.

Diez is correct, please ignore my earlier post on this topic. I have  
2.3 on my machine in that location as well; I didn't look closely  
enough. Apologies for the misinformation.

I'm not answering any more Mac Python questions as I seem to get them  
wrong every time. :-/





From nad at acm.org  Thu Jul 23 17:14:50 2009
From: nad at acm.org (Ned Deily)
Date: Thu, 23 Jul 2009 14:14:50 -0700
Subject: 2.3 missing on OSX
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
Message-ID: <nad-D059A6.14145023072009@news.gmane.org>

In article 
<ce6d734d-620e-46c2-acea-8e48a71a93b6 at n11g2000yqb.googlegroups.com>,
 Laran Evans <laran.evans at gmail.com> wrote:
> I just tried to run MacVim on OSX 10.5. It crashed with this:
> 
> Dyld Error Message:
>   Library not loaded: /System/Library/Frameworks/Python.framework/
> Versions/2.3/Python
>   Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
> MacVim.app/Contents/MacOS/Vim
>   Reason: image not found
> 
> I posted to the MacVim mailing list and was told that that version of
> 2.3 should always be available because it comes with the OS.
> 
> I don't remember if I removed it for whatever reason at some point or
> something. In any case, I have python installed now via MacPorts. I
> have version 2.3 and 2.5 both installed.
> 
> So my question is, is there a way for me to fix the issue by re-
> instating the default 2.3 location or something?

If, in fact, /System/Library/Frameworks/Python.framework/Versions/2.3 is 
empty or missing, you should restore it.   Rule of thumb: everything 
under /System is installed and managed by Apple.  Don't remove things 
from there!  I don't know of a particularly easy way to restore it, 
short of hacking a Leopard installer image or re-installing OS X.  If 
you have an unused external drive or partition, it might be easiest to 
do a vanilla install of Leopard and all software updates, then, from the 
terminal, do a ditto of that directory subtree back to your regular /.

-- 
 Ned Deily,
 nad at acm.org



From __peter__ at web.de  Thu Jul 23 17:20:42 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 23:20:42 +0200
Subject: Problems in commands.getoutput(cmd) with sox
References: <mailman.3618.1248377576.8015.python-list@python.org>
Message-ID: <h4ak72$8vc$02$1@news.t-online.com>

bbarbero at inescporto.pt wrote:

> Hello to all!
> 
> I am a new researcher, new to Python as well, and I have a problem,
> when I try to get commands from sox in a python script. I am going
> crazy, because this code has been working before.. so I dont really
> know whats going on..
> 
> Ive already seen some solutions that match with what I have. I am
> running this:
> 
> 
> 
>          if os.path.splitext(file_au)[1] == ".au":
>            resampled_file_path = os.path.join(resampled_path, file_au)
>             cmd = "sox " + dir_file + " -r 44100 " + resampled_file_path
>             print cmd
> output = commands.getoutput(cmd)
> print output
> 
> What i do, is just to resample a song from dir_file to
> resampled_file_path. As a result of "cmd" I get:
> 
> ....
> sox /Volumes/HAL/Datasets/Audio/gtzan_genres/rock/rock.00097.au -r
> 44100
> 
/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resampled/rock/rock.00097.au
> .....
> 
> If I run this on the command line, it will work perfectly!
> 
> But The program stops at
> 
>   File
> "/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resamplingto44.py",
> line 35
>      output = commands.getoutput(cmd)
>      ^
> IndentationError: unexpected indent
> 
> I dont have any idea, whats going on, I am trying lot of things, but I
> can understand where is the error as it has been running perfectly
> before.
> 
> Any suggestions will be more than welcome! Thanks in advance for your
> help!

You are probably mixing tabs and spaces and have set your editor to display 
a tabsize != 8 spaces.

When you change the tabsize to 8 you will see the inconsistent indentation.

In the future you can avoid such problems by configuring your editor to 
replace one tab with four spaces. Recommended reading:

http://www.python.org/dev/peps/pep-0008/

Peter




From python at mrabarnett.plus.com  Thu Jul 23 17:25:39 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 22:25:39 +0100
Subject: Problems in commands.getoutput(cmd) with sox
In-Reply-To: <20090723212354.5378695qs4beje8a@horde.inescporto.pt>
References: <20090723212354.5378695qs4beje8a@horde.inescporto.pt>
Message-ID: <4A68D553.6090203@mrabarnett.plus.com>

bbarbero at inescporto.pt wrote:
> Hello to all!
> 
> I am a new researcher, new to Python as well, and I have a problem, when 
> I try to get commands from sox in a python script. I am going crazy, 
> because this code has been working before.. so I dont really know whats 
> going on..
> 
> Ive already seen some solutions that match with what I have. I am 
> running this:
> 
> 
> 
>         if os.path.splitext(file_au)[1] == ".au":
>               resampled_file_path = os.path.join(resampled_path, file_au)
>                cmd = "sox " + dir_file + " -r 44100 " + resampled_file_path
>                print cmd
                 ^ extra indent
>         output = commands.getoutput(cmd)
>         print output
> 
> What i do, is just to resample a song from dir_file to 
> resampled_file_path. As a result of "cmd" I get:
> 
> ....
> sox /Volumes/HAL/Datasets/Audio/gtzan_genres/rock/rock.00097.au -r 44100 
> /Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resampled/rock/rock.00097.au 
> 
> .....
> 
> If I run this on the command line, it will work perfectly!
> 
> But The program stops at
> 
>  File 
> "/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resamplingto44.py", 
> line 35
>     output = commands.getoutput(cmd)
>     ^
> IndentationError: unexpected indent
> 
> I dont have any idea, whats going on, I am trying lot of things, but I 
> can understand where is the error as it has been running perfectly before.
> 
> Any suggestions will be more than welcome! Thanks in advance for your help!
> 
You need to double-check the indentation.


From gh at ghaering.de  Thu Jul 23 17:27:08 2009
From: gh at ghaering.de (=?ISO-8859-1?Q?Gerhard_H=E4ring?=)
Date: Thu, 23 Jul 2009 23:27:08 +0200
Subject: Creating xml
In-Reply-To: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
References: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
Message-ID: <h4akjd$6sn$1@ger.gmane.org>

Greg Lindstrom wrote:
> It's been a while since I've played with XML using Python but I've been
> asked to create XML using data from our postgres database.  Currently we
> are generating XML directly from the database using a set of stored
> procedures but it is too slow (yes, I have numbers).  I have been asked
> to create a routine to generate the XML to see if it will be faster that
> the sprocs (which I think it will be, based on other routines we have
> running).  But I digress...

I write to a cStringIO.StringIO instance to create XML. Like this
(pseudo-code):

class Foo:
    def toxml(self, stream):
        print >> stream, "<foo ... />"

If you're concerned about producing valid XML, you can write tests ;-)

> Using my favorite search engine I see that there is a lot of material on
> Python and XML.  At the risk of starting something (which is not my
> intention), what are my options if I want to create xml?  Ceratinly
> writing my own routine is an option, but I bet there are better ones :-)
> 
> How about if I need/want to parse or process an XML file?

Use lxml. It's blazingly fast and its XPath support makes parsing XML a
snap. If you don't want to depend on anything not in the standard
library, use the etree module. Code will be slightly longer because you
don't have XPath support and performance will be only "ok". Not
"super-fast", like with lxml.

HTH

-- Gerhard



From suruti94 at gmail.com  Thu Jul 23 17:45:41 2009
From: suruti94 at gmail.com (Mohan Parthasarathy)
Date: Thu, 23 Jul 2009 14:45:41 -0700
Subject: Bridging Python and C
Message-ID: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>

Hi,
I am a newbie. It looks like there are quite a few ways to bridge Python and
C. I have a bunch of C code and I just need Python wrappers for it. If i
google for this I get SWIG, Boost etc. And I also see

http://www.python.org/doc/2.5.2/ext/intro.html

What is the recommended way for doing this ?

thanks
mohan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/dcb4da17/attachment.html>

From jon at ffconsultancy.com  Thu Jul 23 17:49:13 2009
From: jon at ffconsultancy.com (Jon Harrop)
Date: Thu, 23 Jul 2009 22:49:13 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
	<h4a7kg$q36$1@news.eternal-september.org>
Message-ID: <npmdnbBIr_YeV_XXnZ2dnUVZ8tpi4p2d@brightview.co.uk>

Raffael Cavallaro wrote:
> Yes, you are missing the joke. The point is that if python is 60x
> slower than C, even if there were not a GIL, it would require running
> the python program on a 60 core machine just reach parity with C. The
> existence of the GIL means that in reality you'd probably need a
> several hundred core machine...

No, OCaml is in the same boat as Python. Spawning a parallel work item takes
20,000x longer in OCaml than in F#. Gathering the results is asymptotically
slower in general. Consequently, for most problems, Python or OCaml running
on an infinite number of cores cannot beat F# running on 2 or more (and I
already have 8) because the overheads are far too high for parallelism to
pay off.

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
http://www.ffconsultancy.com/?u


From lists at cheimes.de  Thu Jul 23 17:53:22 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 23:53:22 +0200
Subject: Bridging Python and C
In-Reply-To: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
References: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
Message-ID: <h4am4i$b7n$1@ger.gmane.org>

Mohan Parthasarathy wrote:
> Hi,
> I am a newbie. It looks like there are quite a few ways to bridge Python and
> C. I have a bunch of C code and I just need Python wrappers for it. If i
> google for this I get SWIG, Boost etc. And I also see
> 
> http://www.python.org/doc/2.5.2/ext/intro.html
> 
> What is the recommended way for doing this ?

I recommend Cython (http://cython.org/). I'm using it on a daily bases
to wrap C libraries.

Christian



From philip at semanchuk.com  Thu Jul 23 17:54:33 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 17:54:33 -0400
Subject: Bridging Python and C
In-Reply-To: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
References: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
Message-ID: <12D9D99B-6730-4534-BA61-631A4B9B27FE@semanchuk.com>


On Jul 23, 2009, at 5:45 PM, Mohan Parthasarathy wrote:

> Hi,
> I am a newbie. It looks like there are quite a few ways to bridge  
> Python and
> C. I have a bunch of C code and I just need Python wrappers for it.  
> If i
> google for this I get SWIG, Boost etc. And I also see
>
> http://www.python.org/doc/2.5.2/ext/intro.html
>
> What is the recommended way for doing this ?

"Recommended" depends on what you want to accomplish. SWIG, Boost,  
etc. all have pros and cons.

One option you didn't mention is ctypes which is part of the Python  
standard library. It allows you to pass params to C functions. Works  
great for me!


HTH
Philip



From cmpython at gmail.com  Thu Jul 23 17:54:34 2009
From: cmpython at gmail.com (Che M)
Date: Thu, 23 Jul 2009 14:54:34 -0700 (PDT)
Subject: sqlite3 performance problems only in python
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com> 
	<mailman.3586.1248354168.8015.python-list@python.org>
	<m28wifjm65.fsf@cs.uu.nl> 
	<mailman.3621.1248379117.8015.python-list@python.org>
Message-ID: <a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>

On Jul 23, 3:58?pm, Stef Mientki <stef.mien... at gmail.com> wrote:
> Piet van Oostrum wrote:
> >>>>>> Stef Mientki <stef.mien... at gmail.com> (SM) wrote:
>
> >> SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
> >> SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
> >> SM> ?from OPNAMEN
> >> SM> ? ?inner join POID_VLID ? ? ? ? ?on OPNAMEN.POID ? ? ? ? ? ?= POID_VLID.POID
> >> SM> ? ?inner join VRAAGLST ? ? ? ? ? on VRAAGLST.VLID ? ? ? ? ? = POID_VLID.VLID
> >> SM> ? ?inner join VLID_SSID ? ? ? ? ?on VRAAGLST.VLID ? ? ? ? ? = VLID_SSID.VLID
> >> SM> ? ?inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
> >> SM> ? ?inner join POID_SSID_SCID ? ? on ( OPNAMEN.POID ? ? ? ? ? ?=
> >> SM> POID_SSID_SCID.POID ) and
> >> SM> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ( SUBSCHAAL_GEGEVENS.SSID =
> >> SM> POID_SSID_SCID.SSID )
> >> SM> ? ?inner join SCORES ? ? ? ? ? ? on SCORES.SCID ? ? ? ? ? ? =
> >> SM> POID_SSID_SCID.SCID
> >> SM> ? ?inner join PID_POID ? ? ? ? ? on OPNAMEN.POID ? ? ? ? ? ?= PID_POID.POID
> >> SM> ? ?inner join PATIENT ? ? ? ? ? ?on PATIENT.PID ? ? ? ? ? ? = PID_POID.PID
> >> SM> ?where substr ( lower( NAME) , 1, 6) ?= 'cis20r'
> >> SM> ? ?and lower ( NAME_ ) = 'fatigue'
> >> SM> ? ?and TEST_COUNT in (3,4)
> >> SM> ? ?and DATETIME > 39814.0
> >> SM> ? ?and SCORE < 30
>
> > 1) Do you have indices on the join fields?
>
> well I'm happily surprised, you came up with this suggestion
> - I thought that sqlite created indexes on all primairy key and unique
> fields
> - but after explicitly creating the indices, a gained a speed of about a
> factor 10
> After checking the database creation, it seemed I forgot to make these
> fields the primary key
> so thanks very much.
>
> I gained another factor of 10 speed by updating to version 2.5.5 of
> pysqlite.
>
> cheers,
> Stef
>
> > 2) Look at the ANALYZE command
> > 3) Look at the EXPLAIN command
>
>

You might want to consult the SQLite list for questions like this.

Why do you use pysqlite?  I just import sqlite3 in Python 2.5.
What is the advantage of pysqlite?

Che


From longbotham at gmail.com  Thu Jul 23 18:05:34 2009
From: longbotham at gmail.com (Nathan)
Date: Thu, 23 Jul 2009 15:05:34 -0700 (PDT)
Subject: netCDF4 usage issues
Message-ID: <7c26c9b2-4560-4c16-a01a-68db6c206177@i6g2000yqj.googlegroups.com>

I am having issues correctly implementing the multi-file read
functionality in the Python module netCDF4 (whitaker -
http://code.google.com/p/netcdf4-python/).  I am a relative beginner
to Python, so I may be missing something simple.  I've done my best to
follow the example in the documentation at the website referenced
above (reprinted):

>>> from netCDF4 import MFDataset
>>> f = MFDataset('mftest*nc')
>>> print f.variables['x'][:]
[ 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22
23 24
 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
48 49
 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
73 74
 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99]
>>>

Where I attempt to follow the same flow, I don't get the full data set
returned.  I only get a data set for the first file in my list (see
notes in the code below).

>from netCDF4 import MFDataset
>f = MFDataset('E*nc')   # All files I want to read are .nc files in a single directory, each file starting with E
>temp = f.variables['TEMP'][:]
>temp.shape
Out[17]: (8940, 150)  #This is the exact shape of the TEMP variables
array in the first file I need to read verified by an external netCDF
reader application
>f.file_format #There are two files I am trying to read in this example
Out[33]: ['NETCDF3_CLASSIC', 'NETCDF3_CLASSIC']

Does the module only support netcdf4 files? If so, why is it getting
data out of one of the files?  I'm unsure how to trouble shoot this.

Any suggestions would be appreciated.  If this should be posted
elsewhere, please direct me to another list/forum as I didn't find any
directly related to netCDF or this specific netCDF module.  Thank you!


From http  Thu Jul 23 18:06:22 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 15:06:22 -0700
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>
	<pan.2009.07.23.09.37.54.891000@nowhere.com>
Message-ID: <7xk51zm4v5.fsf@ruckus.brouhaha.com>

Nobody <nobody at nowhere.com> writes:
> They also have the advantage that one thread can run while another is
> waiting on disk I/O, which isn't something which can be done with a
> select/poll interface (even if select/poll worked for files, it doesn't
> help for mapped files).

AIO can help with this, but I don't know any language runtimes that
use it right now.  Really, this (and the similar issue of ram cache
misses) is basically why hardware hyperthreading exists too.  To get
processor parallelism you do have to use OS threads, but green threads
are lighter weight and switch faster, so you want to use a combination
of both.  Basically, use about as many OS threads as you have hardware
threads (i.e. CPU cores or hyperthreads), and then assign green
threads to OS threads in your application runtime.


From lists at cheimes.de  Thu Jul 23 18:08:56 2009
From: lists at cheimes.de (Christian Heimes)
Date: Fri, 24 Jul 2009 00:08:56 +0200
Subject: Looking for os.listdir() generator
In-Reply-To: <slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>
References: <mailman.3584.1248352640.8015.python-list@python.org>
	<slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <h4an1o$di6$1@ger.gmane.org>

Nick Craig-Wood wrote:
> Christian Heimes <lists at cheimes.de> wrote:
>>  I'm looking for a generator version of os.listdir() for Python 2.5 and
>>  newer. I know somebody has worked on it because I've seen a generator
>>  version in a posting on some list or blog a while ago. I can't find it
>>  anymore. It seems my Google fu is lacking today. All I can find is a
>>  very old version of xlistdir. A Cython based solution is appreciated but
>>  please no ctypes version.
> 
> I posted exactly that yesterday I think ;-)
> 
> Note that this has a python part as well as a ctypes part because the
> version of ctypes I used doesn't support generators.  I think the
> development version does though.

Thanks Nick!

ctypes? I'm sure you wanted to say Cython :)

If you don't mind I'm going to wrap it up into a nice package and
release it on PyPI.

Christian



From myzoku at gmail.com  Thu Jul 23 18:14:19 2009
From: myzoku at gmail.com (Gordon)
Date: Thu, 23 Jul 2009 15:14:19 -0700 (PDT)
Subject: Gedcom and Genealogy
Message-ID: <5222a601-a128-4892-9a8d-e1942ac9ce4d@e27g2000yqm.googlegroups.com>

We have many small libraries in JAVA or Ruby that need to be ported to
Python.  Actually it's so simple a rewrite is possible too.


From dr.mtarver at ukonline.co.uk  Thu Jul 23 18:20:04 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Thu, 23 Jul 2009 15:20:04 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3609.1248368502.8015.python-list@python.org>
Message-ID: <f3f73975-384b-4860-96f2-10589aa7a6b0@h11g2000yqb.googlegroups.com>

On 23 July, 18:01, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
> On Thu, 23 Jul 2009 08:48:46 -0700 (PDT), Mark Tarver
> <dr.mtar... at ukonline.co.uk> declaimed the following in
> gmane.comp.python.general:
>
> > I have a very strange error. ?I have two test python files test.py and
> > python.py which contain the following code
>
> ? ? ? ? <snip>
>
> > The other fails with a server configuration error. ?Both are running
>
> ? ? ? ? Way out from left field... Have you tried renaming "python.py" to
> some other name?
>
> ? ? ? ? If the server is configured to treat .py as executable files, it
> might be getting confused over "python.py" trying to invoke "python".
> --
> ? ? ? ? Wulfraed ? ? ? ?Dennis Lee Bieber ? ? ? ? ? ? ? KD6MOG
> ? ? ? ? wlfr... at ix.netcom.com ? ? ? ? ? ? wulfr... at bestiaria.com
> ? ? ? ? ? ? ? ? HTTP://wlfraed.home.netcom.com/
> ? ? ? ? (Bestiaria Support Staff: ? ? ? ? ? ? ? web-a... at bestiaria.com)
> ? ? ? ? ? ? ? ? HTTP://www.bestiaria.com/

Yes; tried pyth.py - still failed.

Mark


From dr.mtarver at ukonline.co.uk  Thu Jul 23 18:27:51 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Thu, 23 Jul 2009 15:27:51 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3614.1248369008.8015.python-list@python.org>
Message-ID: <99dbbe65-adcd-4f06-aa8c-2d7fc25bf94c@s15g2000yqs.googlegroups.com>

On 23 July, 18:01, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
> On Thu, 23 Jul 2009 08:48:46 -0700 (PDT), Mark Tarver
> <dr.mtar... at ukonline.co.uk> declaimed the following in
> gmane.comp.python.general:
>
> > The only hint at a difference I can see is that my ftp program says
> > the files are of unequal lengths. ?test.py is 129 bytes long.
> > python.py 134 bytes long.
>
> ? ? ? ? Just a guess...
>
> ? ? ? ? Line endings... <lf> vs <cr><lf>
>
> --
> ? ? ? ? Wulfraed ? ? ? ?Dennis Lee Bieber ? ? ? ? ? ? ? KD6MOG
> ? ? ? ? wlfr... at ix.netcom.com ? ? ? ? ? ? wulfr... at bestiaria.com
> ? ? ? ? ? ? ? ? HTTP://wlfraed.home.netcom.com/
> ? ? ? ? (Bestiaria Support Staff: ? ? ? ? ? ? ? web-a... at bestiaria.com)
> ? ? ? ? ? ? ? ? HTTP://www.bestiaria.com/

Is that linefeed + ctrl or what?  I can't pick up any difference
reading the files char by char in Lisp.  How do you find the
difference?

Mark


From stef.mientki at gmail.com  Thu Jul 23 18:29:40 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Fri, 24 Jul 2009 00:29:40 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<mailman.3586.1248354168.8015.python-list@python.org>	<m28wifjm65.fsf@cs.uu.nl>
	<mailman.3621.1248379117.8015.python-list@python.org>
	<a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>
Message-ID: <4A68E454.8040909@gmail.com>

Che M wrote:
> On Jul 23, 3:58 pm, Stef Mientki <stef.mien... at gmail.com> wrote:
>   
>> Piet van Oostrum wrote:
>>     
>>>>>>>> Stef Mientki <stef.mien... at gmail.com> (SM) wrote:
>>>>>>>>                 
>>>> SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>>>> SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>>>> SM>  from OPNAMEN
>>>> SM>    inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>>>> SM>    inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>>>> SM>    inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>>>> SM>    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>>>> SM>    inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>>>> SM> POID_SSID_SCID.POID ) and
>>>> SM>                                     ( SUBSCHAAL_GEGEVENS.SSID =
>>>> SM> POID_SSID_SCID.SSID )
>>>> SM>    inner join SCORES             on SCORES.SCID             =
>>>> SM> POID_SSID_SCID.SCID
>>>> SM>    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>>>> SM>    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>>>> SM>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>>>> SM>    and lower ( NAME_ ) = 'fatigue'
>>>> SM>    and TEST_COUNT in (3,4)
>>>> SM>    and DATETIME > 39814.0
>>>> SM>    and SCORE < 30
>>>>         
>>> 1) Do you have indices on the join fields?
>>>       
>> well I'm happily surprised, you came up with this suggestion
>> - I thought that sqlite created indexes on all primairy key and unique
>> fields
>> - but after explicitly creating the indices, a gained a speed of about a
>> factor 10
>> After checking the database creation, it seemed I forgot to make these
>> fields the primary key
>> so thanks very much.
>>
>> I gained another factor of 10 speed by updating to version 2.5.5 of
>> pysqlite.
>>
>> cheers,
>> Stef
>>
>>     
>>> 2) Look at the ANALYZE command
>>> 3) Look at the EXPLAIN command
>>>       
>>     
>
> You might want to consult the SQLite list for questions like this.
>   
thanks,
but because the same SQL-statement in Delphi performed well,
I thought it was a problem with the Python implementation.
> Why do you use pysqlite?  I just import sqlite3 in Python 2.5.
> What is the advantage of pysqlite?
>   
it's 10 .. 15 times faster then sqlite3 delivered with pyton 2.5.
AFAIK it's nothing different, just a newer version.

cheers,
Stef
> Che
>   



From pavlovevidence at gmail.com  Thu Jul 23 18:39:35 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 15:39:35 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org> 
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com> 
	<pan.2009.07.23.09.37.54.891000@nowhere.com>
Message-ID: <36db2930-b4c9-4308-a267-a41703160580@h21g2000yqa.googlegroups.com>

On Jul 23, 2:37?am, Nobody <nob... at nowhere.com> wrote:
> On Wed, 22 Jul 2009 15:17:52 -0700, Carl Banks wrote:
> > So do all these OSes have some kind of __mega_unifying_poll system
> > call that works for anything that might possibly block, that you can
> > exploit from a user process?
>
> Threads ;)

Yeah, well that was kind of my point, you'd need native threads to do
some of this.

Jean-Paul Calderone seemed to be suggesting that it was possible to
wait for events on sockets, pipes, and IPC semaphores at the same.  I
pointed out that it isn't possible with well-known I/O polling calls
(like select), so there must be some other way, and I was wondering
what it was.

He's a proponent of Twisted, which is a major async framework, and I'd
have to figure that once or twice they've encounted issues like "how
to poll both a semaphore and a socket at the same time", so maybe
they've found a good solution to it.


Carl Banks


From __peter__ at web.de  Thu Jul 23 18:49:47 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 00:49:47 +0200
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3614.1248369008.8015.python-list@python.org>
	<99dbbe65-adcd-4f06-aa8c-2d7fc25bf94c@s15g2000yqs.googlegroups.com>
Message-ID: <h4ape3$n4b$01$1@news.t-online.com>

Mark Tarver wrote:

> On 23 July, 18:01, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
>> On Thu, 23 Jul 2009 08:48:46 -0700 (PDT), Mark Tarver
>> <dr.mtar... at ukonline.co.uk> declaimed the following in
>> gmane.comp.python.general:
>>
>> > The only hint at a difference I can see is that my ftp program says
>> > the files are of unequal lengths.  test.py is 129 bytes long.
>> > python.py 134 bytes long.
>>
>> Just a guess...
>>
>> Line endings... <lf> vs <cr><lf>
>>
>> --
>> Wulfraed        Dennis Lee Bieber               KD6MOG
>> wlfr... at ix.netcom.com             wulfr... at bestiaria.com
>> HTTP://wlfraed.home.netcom.com/
>> (Bestiaria Support Staff:               web-a... at bestiaria.com)
>> HTTP://www.bestiaria.com/
> 
> Is that linefeed + ctrl or what?  I can't pick up any difference
> reading the files char by char in Lisp.  How do you find the
> difference?

carriage-return + linefeed

That's the Windows convention for end-of-line markers. Unix uses linefeed 
only.

If you are on Windows you have to open the file in binary mode to see the 
difference:

>>> open("python.py", "rb").read()
'#!/usr/bin/python\r\nprint "Content-type: 
text/html"\r\nprint\r\nprint"<html>"\r\nprint "<center>Hello, 
Linux.com!</center>"\r\nprint "</html>"'
>>> open("test.py", "rb").read()
'#!/usr/bin/python\nprint "Content-type: text/html"\nprint\nprint 
"<html>"\nprint "<center>Hello, Linux.com!</center>"\nprint "</html>"'
>>>

\n denotes a newline (chr(10))
\r denotes a cr (chr(13))

You can fix the line endings with

open(outfile, "wb").writelines(open(infile, "rU"))

Here "U" denotes "universal newline" mode which recognizes "\r", "\n", and 
"\r\n" as line endings and translates all of these into "\n". "wb" means 
"write binary" which does no conversion. Therefore you'll end up with 
outfile following the Unix convention.

Peter



From lists at cheimes.de  Thu Jul 23 18:54:40 2009
From: lists at cheimes.de (Christian Heimes)
Date: Fri, 24 Jul 2009 00:54:40 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A684B56.3020906@gmail.com>
References: <4A684B56.3020906@gmail.com>
Message-ID: <4A68EA30.5060006@cheimes.de>

Stef Mientki schrieb:
> hello,
> 
> until now I used only small / simple databases in Python with sqlite3.
> Now I've a large and rather complex database.
> 
> The most simple query (with just a result of 100 rows),
> takes about 70 seconds.
> And all that time is consumed in "cursor.fetchall"
> 
> Using the same database in Delphi,
> using the same query,
> takes less than 5 seconds (including displaying the full table in a grid).

Side note:

Since you are coming from Delphi you are probably glad to hear that
Firebird (formally known as Borland InterBase) is well supported. The
kinterbasdb DBA provides a DBA 2.0 compatible interface plus lots of
additional Firebird specific features. You might be better of using
Firebird if you need large and complex databases.

With Firebird you can then create a lower case index:

  CREATE INDEX idx_lower_name ON table COMPUTED BY (LOWER(name));

and use it to query the table for lower case names with:

  SELECT ... FROM table t WHERE LOWER(t.name) STARTING WITH LOWER(:query)

or maybe:

  SELECT ... FROM table t WHERE t.name STARTING WITH LOWER(:query) PLAN
JOIN (t INDEX(idx_lower_name));

Firebird 2.1 supports even more useful features to join on columns
without falling back to a full table scan like UNICODE_CI.

Christian


From david at boddie.org.uk  Thu Jul 23 18:58:19 2009
From: david at boddie.org.uk (David Boddie)
Date: Fri, 24 Jul 2009 00:58:19 +0200
Subject: Pyserial and pyQt
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
	<h45inh$ofk$1@get-news01.get.basefarm.net>
	<70e4ebae-908f-4f3a-a96a-6fa0a7a7887a@y19g2000yqy.googlegroups.com>
	<mailman.3572.1248336905.8015.python-list@python.org>
Message-ID: <h4apub$gov$1@get-news01.get.basefarm.net>

On Thursday 23 July 2009 10:13, Dennis Lee Bieber wrote:

> On Wed, 22 Jul 2009 10:32:51 -0700 (PDT), Seth <king.seth at gmail.com>
> declaimed the following in gmane.comp.python.general:
> 
>> Thanks for the response.  I have gone through a lot of the tutorials.
>> All of them(that I saw) seem to just deal will event-based
>> applications ie calculator, image viewer, etc.  How do I run pyserial
>> in the background and pass the information to PyQT and refresh the
>> screen?  Is there a way to have pyserial run in another thread and
>> pass the information to the UI?
>>
> So far as I've experienced (which isn't all that much), most all GUI
> frameworks support some method of defining either: 1) a work routine
> which will be called whenever the input event queue is empty -- work
> routines should be coded to do a very short, fast, bit of processing and
> return, so the event dispatcher can continue (collect one character at a
> time, or one line using a non-blocking I/O operation; or use a thread to
> collect and post via a Queue) (wx.EVT_IDLE [bind to your idle handler] &
> wx.WakeUpIdle() [call from thread after posting to queue]);

I think I can say that idle processing isn't a common idiom in PyQt
applications. After all, you can't guarantee that your application will be
idle or be able to use up idle time in a way that you can rely on, and
perhaps it isn't a good situation to be in if your framework is using up
CPU time by idling.

> 2) a timed-event which the dispatcher can call at periodic intervals (use
> a thread to collect lines from the serial port, post the lines via a
> Queue, and have the timed event check for queued data) (wx.Timer() );

In PyQt, the easiest way to do this is with a timer, connecting its
timeout() signal to a slot (method) to perform some processing. A widget
class might be adapted to do this in the following way:

  class MyWindow(QWidget):
    def __init__(self):
      QWidget.__init__(self)
      # ... other initialisation ...
      
      timer = QTimer(self)
      timer.timeout.connect(self.processData) # PyQt 4.5 signal notation
      timer.start(100)                        # every 100 milliseconds
    
    def processData(self):
      # Do your processing here.

There are various ways to use timers with PyQt, but this is a fairly simple
pattern to use.

> 3) a callback interface to the GUI event dispatcher which can be invoked
> from a separate thread (wx.CallAfter() )

I think at this point I would recommend using a separate thread. The idiom
for using threads with PyQt is quite simple, though it helps to go with the
framework and use QThread instead of Python's thread class.

> You'll have to track down the equivalent QT functions (I have to
> confess, I found the above from "wxPython in Action"; my last real GUI
> coding that needed such was nearly 20 years ago, using xt and DECWindows
> for the interface, and GKS on X for the data drawing, emulating an
> archaic Ramtek graphics engine command set. The idle/work routine
> collected commands sent via VMS mailbox to the "display" and generated
> GKS operations for them).

The people demand screenshots! ;-)

David


From timro21 at gmail.com  Thu Jul 23 19:02:23 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 16:02:23 -0700 (PDT)
Subject: integer square roots
Message-ID: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>

I wish to process billions of 100-digit numbers and test if each has
an integer square root.  What's the most efficient way to do this?


From davea at ieee.org  Thu Jul 23 19:03:14 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 23 Jul 2009 19:03:14 -0400
Subject: strange python scripting error
In-Reply-To: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
Message-ID: <4A68EC32.4090907@ieee.org>

Mark Tarver wrote:
> I have a very strange error.  I have two test python files test.py and
> python.py which contain the following code
>
> #!/usr/bin/python
> print "Content-type: text/html"
> print
> print "<html>"
> print "<center>Hello, Linux.com!</center>"
> print "</html>"
>
> One file (test.py) works; you call it up and it shows a web page with
>
> Hello, Linux.com
>
> The other fails with a server configuration error.  Both are running
> under Linux, same server, same permissions.  Running a character scan
> shows that both files contain the same printable characters and are
> therefore typographically identical.   They are absolutely the same.
>
> The only hint at a difference I can see is that my ftp program says
> the files are of unequal lengths.  test.py is 129 bytes long.
> python.py 134 bytes long.
>
> A zipped folder containing both files is at
>
> www.lambdassociates.org/weird.zip
>
> Any ideas welcome.
>
> Mark
>
>   
Easiest explanation is that python.py has Windows-style newlines.  In 
other words, each line ends with 0d0a, rather than the Unix convention 
of 0a.

If your server is Unix-based, it can't handle that first line, since it 
has an illegal character (0d) following the

#!/usr/bin/python

line.  Convert it to Unix line-endings.

DaveA


From gagsl-py2 at yahoo.com.ar  Thu Jul 23 19:14:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 23 Jul 2009 20:14:07 -0300
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst>
	<mailman.3560.1248307583.8015.python-list@python.org>
	<74cd3059-cd88-418b-8444-766a125d93c3@y4g2000prf.googlegroups.com>
Message-ID: <op.uxjmtteix6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 10:19:33 -0300, DG <dangets at gmail.com> escribi?:
> On Jul 22, 6:05?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>> En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James ?
>> <rho... at wildebst.demon.co.uk> escribi?:
>>
>> > On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina ?
>> > <gagsl-... at yahoo.com.ar> wrote:
>>
>> >> class X(object):
>> >> ? ?foo = descriptor()
>>
>> >> x = X()
>> >> x.foo = "value"
>>
> You might've already thought of this (and it is annoying), but you
> could pass the name through the descriptor's init method.  I believe
> this is the only way besides assigning a metaclass that will look for
> that type of descriptor upon class creation and set the descriptor's
> name at that time.
>
> class A(object):
>     def __init__(self, attr_name):
>         self._name = attr_name
>     def __set__(self, instance, value):
>         self.instance.__dict__[self._name] = value
>         # or something like that...
>
> class B(object):
>     foo = A('foo')

Thanks, this seems to be the less "magical" solution. I don't like having  
to repeat the attribute name, but nothing is perfect...
And thanks to Rainer Mansfeld too; looking up the matching attribute may  
be useful in other cases.

-- 
Gabriel Genellina



From pavlovevidence at gmail.com  Thu Jul 23 19:30:54 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 16:30:54 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
	<7xws60p7kk.fsf@ruckus.brouhaha.com>
Message-ID: <6a3f1211-b551-4012-904c-0ed0a2c9f6f8@o32g2000yqm.googlegroups.com>

On Jul 22, 5:27?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > I don't think your fantasy async-only all-green-thread langauge
> > implementation is possible anyway.
>
> Erlang and GHC both work like that, quite successfully:
>
> ?http://shootout.alioth.debian.org/gp4/benchmark.php?test=threadring&l...

I am not suggesting that you can't do a lot of things with async I/O.
But can you do *everything* that native threads can do?  I don't think
so.

So when you asked:

"Why is that [native threading] such an advantage?  Green threads work
fine if you just
organize the i/o system to never block."

Well, the answer is they don't always work fine.  Just organizing the
I/O system never to block won't cut it, since things other than I/O
block.  For green threads to work fine all the time you have to be
able organize your entire system never to block, and I don't think
it's possible on the common OSes in use today.  Until that happens,
there will always be advantages to being able to use native threads on
a single core.


> > How would you wait on a pipe in one thread, a socket in another, a
> > semaphore in a third? ?
>
> You can select on pipes and sockets, I think. ?Not sure about
> semaphores. ?

So you made a claim that "green threads work fine", and rhetorically
suggested that native threads had no advantages, yet you're not even
100% sure you can select on both pipes and sockets (both common forms
of I/O), let alone semaphores?

[You can select on sockets and pipes in Unix, not in Windows, although
on Windows I think there are other ways to do it besides the select
call.]


> > (Are there any popular OSes that offer a unified polling interface to
> > all possible synchronizations?) ?And what do you do about drivers or
> > libraries that make underlying blocking calls? ?What if you have a
> > busy calculation going on in the background?
>
> I don't think the concept of "drivers" applies to user-mode programs.
> For FFI calls you would use an OS thread.

That's contrary to the hypothesis, isn't it?

>?The language runtime
> switches between busy computation threads on a timer tick.

This would seem to result in a tradeoff between performance and low-
latency.  Well that happens at the OS-level too but the OS can respond
to interrupts and task switch between timer ticks at finer intervals.
Back in my DOS days I wrote user programs that responded to I/O
interrupts, but it doesn't seem to be common practice in modern OSes
to easily allow this.


And Paul, if I'm being a little hard on you here, it's not that I'm
taking issue with your own claim so much as with your dismissal of
mine.


Carl Banks


From scriptlearner at gmail.com  Thu Jul 23 19:39:29 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Thu, 23 Jul 2009 16:39:29 -0700 (PDT)
Subject: passing data to a liburl2 opener object
Message-ID: <89de6563-1016-461b-87b6-090754ca224b@r2g2000yqm.googlegroups.com>

I have prepared my headers and data for a HTTP POST message; however,
I am not sure how to pass the data to the opener.  Can you guys
provide some suggestions?  Thanks.


proxy_handler = urllib2.ProxyHandler({'http': 'http://my.proxy.com:
3128/'})
opener = urllib2.build_opener(proxy_handler)

url = "http://sample.company.com:9999/service?"

headers['Content-Type'] = 'multipart/form-data; boundary=%s' %
myBoundar
headers['Cookie'] = 'somevalidcookiecontents'
#there is an opener.addheaders method for adding headers
data = multipart_encode(myDict)
#how to pass data to the opener???


With the codes above, I need to send out a HTTP POST like the
following one:

POST http://sample.company.com:9999/service?
Content-Type: multipart/form-data;
boundary=---------------------------1234

---------------------------1234
Content-Disposition: form-data; name="picture"

PICTURE contents here
---------------------------1234
Content-Disposition: form-data; name="id"

whateverid
---------------------------1234--


From shai at platonix.com  Thu Jul 23 19:51:43 2009
From: shai at platonix.com (Shai)
Date: Thu, 23 Jul 2009 16:51:43 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
	<87ljmogglz.fsf@benfinney.id.au>
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <056f629b-aa63-458a-ae16-ac40a759e446@h11g2000yqb.googlegroups.com>

On Jul 17, 10:52?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
>
> When the decorator is called, the function object is just a function
> object, not a method, so there is no concept of "what class it is
> destined for".
>

... which points to the better solution: use a descriptor. With the
doc_inherit decorator defined below, one may write

class Foo(object):
    def foo(self):
        "Frobber"
        pass

class Bar(Foo):
    @doc_inherit
    def foo(self):
        pass

and it appears to work. The code below is a little longish because we
need to do slightly different things when called for a class and for
an instance. But there's no need to repeat the parent name, no need
to look into namespaces (which, as you said, is probably messy and
fragile), and it seems pretty readable, too.

from functools import wraps

class DocInherit(object):
    """
    Docstring inheriting method descriptor

    The class itself is also used as a decorator
    """

    def __init__(self, mthd):
        self.mthd = mthd
        self.name = mthd.__name__

    def __get__(self, obj, cls):
        if obj:
            return self.get_with_inst(obj, cls)
        else:
            return self.get_no_inst(cls)

    def get_with_inst(self, obj, cls):

        overridden = getattr(super(cls, obj), self.name, None)

        @wraps(self.mthd, assigned=('__name__','__module__'))
        def f(*args, **kwargs):
            return self.mthd(obj, *args, **kwargs)

        return self.use_parent_doc(f, overridden)

    def get_no_inst(self, cls):

        for parent in cls.__mro__[1:]:
            overridden = getattr(parent, self.name, None)
            if overridden: break

        @wraps(self.mthd, assigned=('__name__','__module__'))
        def f(*args, **kwargs):
            return self.mthd(*args, **kwargs)

        return self.use_parent_doc(f, overridden)

    def use_parent_doc(self, func, source):
        if source is None:
            raise NameError, ("Can't find '%s' in parents"%self.name)
        func.__doc__ = source.__doc__
        return func

doc_inherit = DocInherit

Combining docstrings (as suggested by Jean-Paul Calderone), and
taking proper care of classmethods and staticmethods, are left
as an exercise to the reader.

Have fun,
Shai.


From davea at ieee.org  Thu Jul 23 19:52:22 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 23 Jul 2009 19:52:22 -0400
Subject: Bridging Python and C
In-Reply-To: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
References: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
Message-ID: <4A68F7B6.2020101@ieee.org>

Mohan Parthasarathy wrote:
> Hi,
> I am a newbie. It looks like there are quite a few ways to bridge Python and
> C. I have a bunch of C code and I just need Python wrappers for it. If i
> google for this I get SWIG, Boost etc. And I also see
>
> http://www.python.org/doc/2.5.2/ext/intro.html
>
> What is the recommended way for doing this ?
>
> thanks
> mohan
>
>   
I think the real question to ask is what form is your C code in.  If 
you're in Windows, and it's compiled into DLL's with documented exports, 
then I'd start by using ctypes to access a few of the exports.  If that 
seems too hard, you might try SWIG or another automated tool, to parse 
the headers and generate wrappers.  But if you haven't done it first by 
hand, you might find the automated tools very hard to figure out.

DaveA


From http  Thu Jul 23 19:57:10 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 16:57:10 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
	<7xws60p7kk.fsf@ruckus.brouhaha.com>
	<6a3f1211-b551-4012-904c-0ed0a2c9f6f8@o32g2000yqm.googlegroups.com>
Message-ID: <7x8wifymuh.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> > I don't think the concept of "drivers" applies to user-mode programs.
> > For FFI calls you would use an OS thread.
> That's contrary to the hypothesis, isn't it?

Yeah, it would have been better to say, green threads are ok for most
typical forms of i/o concurrency, but OS threads are still necessary
for some things.  An FFI call in particular isn't exactly under the
control of your language's runtime system; it has to be treated
more like an external program.

OS thread?switching is much more expensive than green thread
switching, so it's still preferable to use green threads when
possible.

> >?The language runtime switches between busy computation threads on
> >?a timer tick.
> This would seem to result in a tradeoff between performance and low-
> latency. 

GHC appears to use a 100 hz timer, which I'd expect to be fast enough
for interactive applications while still not causing too much cpu
load.  I don't know if it has a way to assign priorities to
microthreads (e.g. if you have one running your program's GUI) though.

I don't think either Python or GHC can implement hard-real-time
latency because they both use stop-the-world garbage collection.
E.g. in Python, releasing the last reference to a large list or dict
can take a long time.

> And Paul, if I'm being a little hard on you here, it's not that I'm
> taking issue with your own claim so much as with your dismissal of
> mine.

Well, the issue was why Python uses native threads pervasively.  As
far as I can tell, it's just an implementation artifact that has no
really compelling justification.


From mensanator at aol.com  Thu Jul 23 20:11:54 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 23 Jul 2009 17:11:54 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
Message-ID: <73b8529d-23f4-41b4-a6cd-9f191f74bcd4@y19g2000yqy.googlegroups.com>

On Jul 23, 6:02?pm, timro21 <timr... at gmail.com> wrote:
> I wish to process billions of 100-digit numbers and test if each has
> an integer square root. ?What's the most efficient way to do this?

Use gmpy.

>>> import gmpy
>>> help(gmpy.sqrt)

Help on built-in function sqrt in module gmpy:

sqrt(...)
    sqrt(x): returns the integer, truncated square root of x, i.e. the
    largest y such that x>=y*y. x must be an mpz, or else gets coerced
    to one; further, x must be >= 0.

>>> p = 10**100

>>> p1 = gmpy.next_prime(p)

>>> p1
mpz
(10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000267)

>>> gmpy.sqrt(p1)
mpz(100000000000000000000000000000000000000000000000000)




From mensanator at aol.com  Thu Jul 23 20:17:53 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 23 Jul 2009 17:17:53 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<73b8529d-23f4-41b4-a6cd-9f191f74bcd4@y19g2000yqy.googlegroups.com>
Message-ID: <ad3518c1-655c-428b-81b1-e1d8b23384c1@o6g2000yqj.googlegroups.com>

On Jul 23, 7:11?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 23, 6:02?pm, timro21 <timr... at gmail.com> wrote:
>
> > I wish to process billions of 100-digit numbers and test if each has
> > an integer square root. ?What's the most efficient way to do this?
>
> Use gmpy.
>
> >>> import gmpy
> >>> help(gmpy.sqrt)
>
> Help on built-in function sqrt in module gmpy:
>
> sqrt(...)
> ? ? sqrt(x): returns the integer, truncated square root of x, i.e. the
> ? ? largest y such that x>=y*y. x must be an mpz, or else gets coerced
> ? ? to one; further, x must be >= 0.
>
> >>> p = 10**100
> >>> p1 = gmpy.next_prime(p)
> >>> p1
>
> mpz
> (10000000000000000000000000000000000000000000000000000000000000000000000000?000000000000000000000000267)
>
> >>> gmpy.sqrt(p1)
>
> mpz(100000000000000000000000000000000000000000000000000)

Duh. I completely misread this. I thought you wanted the square root,
not IF it had a square root that's an integer.

Sorry about that.

Try this, instead:

>>> gmpy.sqrtrem(p1)
(mpz(100000000000000000000000000000000000000000000000000), mpz(267))

It has a non-zero remainder, so it's not an integer square root.


From aahz at pythoncraft.com  Thu Jul 23 20:25:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 23 Jul 2009 17:25:16 -0700
Subject: Help understanding the decisions *behind* python?
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
	<mailman.3616.1248369685.8015.python-list@python.org>
Message-ID: <h4av1c$6eh$1@panix3.panix.com>

In article <mailman.3616.1248369685.8015.python-list at python.org>,
Mark Lawrence  <breamoreboy at yahoo.co.uk> wrote:
>
>Sorry if this has been discussed and I've missed it, but how about 
>memory allocation.  An immutable tuple has a fixed memory allocation 
>whereas that for the mutable list must be liable to change.  You might 
>like to look at the recent thread on this ng 'List insertion cost' and 
>follow the links to Raymond Hettinger's power point presentation.

Not only that, but lists use more memory, period, for any given number of
elements because the overallocation permits amortized constant time for
appends.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From aahz at pythoncraft.com  Thu Jul 23 20:27:35 2009
From: aahz at pythoncraft.com (Aahz)
Date: 23 Jul 2009 17:27:35 -0700
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
	<EgE9m.507$646.499@nwrddc01.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
Message-ID: <h4av5n$p1l$1@panix3.panix.com>

In article <mailman.3561.1248307942.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>
>NLMPI

What?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From mensanator at aol.com  Thu Jul 23 20:30:34 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 23 Jul 2009 17:30:34 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<73b8529d-23f4-41b4-a6cd-9f191f74bcd4@y19g2000yqy.googlegroups.com> 
	<ad3518c1-655c-428b-81b1-e1d8b23384c1@o6g2000yqj.googlegroups.com>
Message-ID: <e8394cb1-9630-4e4e-8770-6cf70766ea1e@b15g2000yqd.googlegroups.com>

On Jul 23, 7:17?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 23, 7:11?pm, Mensanator <mensana... at aol.com> wrote:
>
>
>
>
>
> > On Jul 23, 6:02?pm, timro21 <timr... at gmail.com> wrote:
>
> > > I wish to process billions of 100-digit numbers and test if each has
> > > an integer square root. ?What's the most efficient way to do this?
>
> > Use gmpy.
>
> > >>> import gmpy
> > >>> help(gmpy.sqrt)
>
> > Help on built-in function sqrt in module gmpy:
>
> > sqrt(...)
> > ? ? sqrt(x): returns the integer, truncated square root of x, i.e. the
> > ? ? largest y such that x>=y*y. x must be an mpz, or else gets coerced
> > ? ? to one; further, x must be >= 0.
>
> > >>> p = 10**100
> > >>> p1 = gmpy.next_prime(p)
> > >>> p1
>
> > mpz
> > (10000000000000000000000000000000000000000000000000000000000000000000000000??000000000000000000000000267)
>
> > >>> gmpy.sqrt(p1)
>
> > mpz(100000000000000000000000000000000000000000000000000)
>
> Duh. I completely misread this. I thought you wanted the square root,
> not IF it had a square root that's an integer.
>
> Sorry about that.
>
> Try this, instead:
>
> >>> gmpy.sqrtrem(p1)
>
> (mpz(100000000000000000000000000000000000000000000000000), mpz(267))
>
> It has a non-zero remainder, so it's not an integer square root.

There's also

   is_square(...)
        is_square(x): returns 1 if x is a perfect square, else 0.
        x must be an mpz, or else gets coerced to one.



From http  Thu Jul 23 20:35:27 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 17:35:27 -0700
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
Message-ID: <7x4ot2zzn4.fsf@ruckus.brouhaha.com>

timro21 <timro21 at gmail.com> writes:
> I wish to process billions of 100-digit numbers and test if each has
> an integer square root.  What's the most efficient way to do this?

Is this a homework problem?  If not, may I ask what the application is?

I think the basic answer is 1) use the law of quadratic reciprocity to
eliminate a lot of the inputs quickly (for example, just looking at
the low 8 bits of an input number should eliminate about 5/6th of
them); 2) use GMP and Newton's method to check the rest.
http://cr.yp.to/papers/powers.pdf has some advice about how to do
that.

sci.crypt might be another good place to ask this question.


From songofacandy at gmail.com  Thu Jul 23 20:49:26 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Thu, 23 Jul 2009 17:49:26 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>
Message-ID: <784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>

>  What is the encoding of sys.stderr in your example?
Sorry, I missed. It is cp932

> So the problem is essentially this: if a stream has an encoding
> attribute, sometimes it is a wrapped stream which encodes Unicode
> (e.g. a stream obtained via the codecs module) and sometimes it is not
> (e.g. sys.stdout, sys.stderr).

Yes! I confused by it.

>> The encoding that this file uses. When Unicode strings are written to a file,
>>  they will be converted to byte strings using this encoding. In addition,
>> when the file is connected to a terminal, the attribute gives the encoding
>> that the terminal is likely to use

I feel this doc means "file object with encoding attribute encodes
unicode
regardless it is tty or not" and sys.stdout/stderr defies convention.

If this doc means "file object encodes unicode if it isn't tty.", I
should write
like below::

if not afile.isatty():
    if getattr(afile, "encoding") is not None:
        afile.write(unicode_str)
elif getattr(afile, "encoding") is not None:
    afile.write(unicode_str.encode(afile.encoding))
else:
    afile.write(unicode_str.encode(fallback_encoding)) # utf8,
defaultencoding, preferedencoding, ...


"Writing unicode to a file(-like)" is a simple requirement.
Does python have any simple resolution for it?


From rui.maciel at gmail.com  Thu Jul 23 20:52:00 2009
From: rui.maciel at gmail.com (Rui Maciel)
Date: Fri, 24 Jul 2009 01:52 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <4a6905b0$0$27110$a729d347@news.telepac.pt>

fft1976 wrote:

> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

Probably due to similar reasons that lead php to become remotely relevant.


Rui Maciel


From timro21 at gmail.com  Thu Jul 23 21:00:20 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 18:00:20 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
Message-ID: <fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>

On Jul 24, 10:35?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> timro21 <timr... at gmail.com> writes:
> > I wish to process billions of 100-digit numbers and test if each has
> > an integer square root. ?What's the most efficient way to do this?
>
> Is this a homework problem? ?If not, may I ask what the application is?
>
> I think the basic answer is 1) use the law of quadratic reciprocity to
> eliminate a lot of the inputs quickly (for example, just looking at
> the low 8 bits of an input number should eliminate about 5/6th of
> them); 2) use GMP and Newton's method to check the rest.http://cr.yp.to/papers/powers.pdfhas some advice about how to do
> that.
>
> sci.crypt might be another good place to ask this question.

Homework?  Gosh no.  I have several number theory applications which
need to know (quickly) whether particular very large numbers are
perfect squares.  Since I asked this in this newsgroup I guess I
assumed that responses wuld relate specifically to how to do this
efficiently *and accurately* in Python.  Sorry if I wasn't clear.


From dstanek at dstanek.com  Thu Jul 23 21:23:06 2009
From: dstanek at dstanek.com (David Stanek)
Date: Thu, 23 Jul 2009 21:23:06 -0400
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A68E454.8040909@gmail.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<mailman.3586.1248354168.8015.python-list@python.org>
	<m28wifjm65.fsf@cs.uu.nl>
	<mailman.3621.1248379117.8015.python-list@python.org>
	<a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>
	<4A68E454.8040909@gmail.com>
Message-ID: <de32cc030907231823n29ab86c8n7cdba1832be059dd@mail.gmail.com>

On Thu, Jul 23, 2009 at 6:29 PM, Stef Mientki<stef.mientki at gmail.com> wrote:
>
> but because the same SQL-statement in Delphi performed well,
> I thought it was a problem with the Python implementation.

Same SQL, but were you also using Sqlite in Delphi?

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From http  Thu Jul 23 21:51:01 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 18:51:01 -0700
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
Message-ID: <7xzlaudf22.fsf@ruckus.brouhaha.com>

timro21 <timro21 at gmail.com> writes:
> Homework?  Gosh no.  I have several number theory applications which
> need to know (quickly) whether particular very large numbers are
> perfect squares.  Since I asked this in this newsgroup I guess I
> assumed that responses wuld relate specifically to how to do this
> efficiently *and accurately* in Python.  Sorry if I wasn't clear.

comp.lang.python is a good place to get answers about Python.  It's
probably not such a good source of answers about computational number
theory.  Also, Python is more about productivity than speed, so
answers involving Python may not be the most efficient possible
answers.  One obvious point though is that GMP/gmpy is pretty simple
to use from Python and will be several times faster than Python's
built in longs.  Also, as Mensanator pointed out, GMP has built-in
functions that will help you with precise checks (I'd forgotten or not
known about them).  I still think you'd get a speedup from first
filtering out obviously non-square candidates before resorting to
multi-precision arithmetic.  Some other fairly simple optimization may
be possible too.

I asked about the application mainly because I wondered if you had
realtime requirements, whether you were going to have to keep doing
this problem with new numbers, etc.  If you just have a 1-off task of
checking a few billion numbers, you could probably do it in a few days
with Python on a workstation using some fairly simple code.  If you
want to check billions of numbers per minute, or if what you really
want is to check trillions of numbers rather than billions, then it's
worth pursuing fancier methods.  Another issue is the source of the
numbers.  E.g. maybe there is a way to program a graphics accelerator
to turn a number into a list of residues mod a bunch of small primes
in parallel and get a fast, near-certain test if the inputs are
random, but that approach could be fooled if the numbers were
concocted by a possible adversary.


From casevh at gmail.com  Thu Jul 23 22:04:50 2009
From: casevh at gmail.com (casevh)
Date: Thu, 23 Jul 2009 19:04:50 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
Message-ID: <aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>

> comp.lang.python is a good place to get answers about Python. ?It's
> probably not such a good source of answers about computational number
> theory. ?Also, Python is more about productivity than speed, so
> answers involving Python may not be the most efficient possible
> answers. ?One obvious point though is that GMP/gmpy is pretty simple
> to use from Python and will be several times faster than Python's
> built in longs. ?Also, as Mensanator pointed out, GMP has built-in
> functions that will help you with precise checks (I'd forgotten or not
> known about them). ?I still think you'd get a speedup from first
> filtering out obviously non-square candidates before resorting to
> multi-precision arithmetic. ?Some other fairly simple optimization may
> be possible too.
>
gmpy.is_square() is quite fast. On a older 32-bit Linux box, it can
test approximately 400,000 100-digits numbers per second. The time
includes conversion from a string. If the numbers are already Python
longs, it can check 800,000 per second. Checking a billion is not
unreasonable.

casevh


From http  Thu Jul 23 22:48:12 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 19:48:12 -0700
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
Message-ID: <7xocra7q4z.fsf@ruckus.brouhaha.com>

casevh <casevh at gmail.com> writes:
> gmpy.is_square() is quite fast. On a older 32-bit Linux box, it can
> test approximately 400,000 100-digits numbers per second. The time
> includes conversion from a string. If the numbers are already Python
> longs, it can check 800,000 per second. Checking a billion is not
> unreasonable.

Wow, that is pretty impressive.  A look at the code shows it uses
quite a few optimizations:

http://sage.math.washington.edu/home/novoselt/gmp-4.2.4/mpn/perfsqr.c


From songofacandy at gmail.com  Thu Jul 23 23:10:10 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Thu, 23 Jul 2009 20:10:10 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com> 
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>
Message-ID: <ebe8014b-5323-4cb6-99ec-5612b390130a@d9g2000prh.googlegroups.com>

>
> Yes! I confused by it.

s/I confused/I am confused/

> "Writing unicode to a file(-like)" is a simple requirement.
> Does python have any simple resolution for it?

s/resolution/solution/

Sorry about my poor English.


From pavlovevidence at gmail.com  Thu Jul 23 23:11:23 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 20:11:23 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com> 
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
	<7xws60p7kk.fsf@ruckus.brouhaha.com>
	<6a3f1211-b551-4012-904c-0ed0a2c9f6f8@o32g2000yqm.googlegroups.com>
	<7x8wifymuh.fsf@ruckus.brouhaha.com>
Message-ID: <d154c2d9-82c2-4897-815b-2c675b9684f6@q11g2000yqi.googlegroups.com>

On Jul 23, 4:57?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > > I don't think the concept of "drivers" applies to user-mode programs.
> > > For FFI calls you would use an OS thread.
> > That's contrary to the hypothesis, isn't it?
>
> Yeah, it would have been better to say, green threads are ok for most
> typical forms of i/o concurrency, but OS threads are still necessary
> for some things. ?An FFI call in particular isn't exactly under the
> control of your language's runtime system; it has to be treated
> more like an external program.
>
> OS thread?switching is much more expensive than green thread
> switching, so it's still preferable to use green threads when
> possible.

That is reasonable.  Thank you.


> > And Paul, if I'm being a little hard on you here, it's not that I'm
> > taking issue with your own claim so much as with your dismissal of
> > mine.
>
> Well, the issue was why Python uses native threads pervasively. ?As
> far as I can tell, it's just an implementation artifact that has no
> really compelling justification.

Probably for this reason: "Because then they didn't have to arrange
for the I/O to never block."


Carl Banks


From timro21 at gmail.com  Thu Jul 23 23:30:25 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 20:30:25 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
Message-ID: <2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>


Thanks to all!

Tim


From pavlovevidence at gmail.com  Thu Jul 23 23:51:02 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 20:51:02 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
Message-ID: <a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>

On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
> fft1976 wrote:
> > How do you explain that something as inferior as Python beat Lisp in
> > the market place despite starting 40 years later.
>
> Probably due to similar reasons that lead php to become remotely relevant.

Well, the only reason PHP became relevant because it was an easy to
deploy solution in a single application domain, the web, that happened
to explode.

The same thing happened to Python.

Oh, wait, no it didn't.


Carl Banks


From tundra at tundraware.com  Thu Jul 23 23:51:26 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Thu, 23 Jul 2009 22:51:26 -0500
Subject: integer square roots
In-Reply-To: <2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
Message-ID: <rmnnj6-f922.ln1@ozzie.tundraware.com>

timro21 wrote:
> Thanks to all!
> 
> Tim

While we're at it, would you mind saying more about what exactly you're
doing - Inquiring Math Dorks (tm) want to know ...

-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From icebergwtf at gmail.com  Thu Jul 23 23:58:04 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Fri, 24 Jul 2009 11:58:04 +0800
Subject: extract c/cpp include file with regular expression
In-Reply-To: <slrnh6he16.dgi.nick@irishsea.home.craig-wood.com>
References: <mailman.3597.1248363967.8015.python-list@python.org>
	<slrnh6he16.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <4314c1f70907232058t4d295a25t86ba11d90e15001d@mail.gmail.com>

Thanks, Philip Semanchuk and Nick Craig-Wood!
My goal is gather informations from cpp sources and generate cross
referenced html files (as more detail as fine)
So I think " missing some unusual cases" might be acceptable, but
informations you introduced make me more interests to dig things out
:)
I know some programs like doxygen do such things, but I can learn much
by doing this than simply write configuration files.

cheers!

tiefeng wu
2009-07-24


From rurpy at yahoo.com  Fri Jul 24 00:19:52 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Thu, 23 Jul 2009 21:19:52 -0700 (PDT)
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
	<zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com>
Message-ID: <e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com>

Nick Dumas wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Agreed. Two string.split()s, first at the semi-colon and then at the
> equal sign, will yield you your value, without having to fool around
> with regexes.
>
> On 7/23/2009 9:23 AM, Mark Lawrence wrote:
>> scriptlearner at gmail.com wrote:
>>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>>> will like to take out the values (valuea, valueb, and valuec).  How do
>>> I do that in Python?  The group method will only return the matched
>>> part.  Thanks.
>>>
>>> p = re.compile('#a=*;b=*;c=*;')
>>> m = p.match(line)
>>>         if m:
>>>              print m.group(),
>>
>> IMHO a regex for this is overkill, a combination of string methods such
>> as split and find should suffice.

You're saying that something like the following
is better than the simple regex used by the OP?

[untested]
values = []
parts = line.split(';')
if len(parts) != 4: raise SomeError()
for p, expected in zip (parts[-1], ('#a','b','c')):
    name, x, value = p.partition ('=')
    if name != expected or x != '=':
        raise SomeError()
    values.append (value)
print values[0], values[1], values[2]

Blech, not in my book.  The regex checks the
format of the string, extracts the values, and
does so very clearly.  Further, it is easily
adapted to other similar formats, or evolutionary
changes in format.  It is also (once one is
familiar with regexes -- a useful skill outside
of Python too) easier to get right (at least in
a simple case like this.)

The only reason I can think of to prefer
a split-based solution is if this code were
performance-critical in that I would expect
the split code to be faster (although I don't
know that for sure.)

This is a perfectly fine use of a regex.


From d at vidr.cc  Fri Jul 24 00:27:10 2009
From: d at vidr.cc (David Roberts)
Date: Fri, 24 Jul 2009 14:27:10 +1000
Subject: OverflowError in RLock.acquire()
Message-ID: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>

Hi,

I'm trying to port a Python application to Windows, and I'm getting
the following error (which did not occur when running on Linux):

Exception in thread Thread-4:
Traceback (most recent call last):
  File "C:\Python26\lib\threading.py", line 525, in __bootstrap_inner
    self.run()
  File "C:\Documents and Settings\David\My
Documents\pyzui\pyzui\tileprovider.py", line 97, in run
    self.__tilecache[tile_id] = Tile(tile)
  File "C:\Documents and Settings\David\My
Documents\pyzui\pyzui\tilecache.py", line 165, in __setitem__
    with self.__lock:
  File "C:\Python26\lib\threading.py", line 115, in acquire
    me = current_thread()
  File "C:\Python26\lib\threading.py", line 803, in currentThread
    return _active[_get_ident()]
OverflowError: can't convert negative value to unsigned long

Where __lock is an RLock object.

The error only occurs for a single class (which is derived from the
TileProvider class in tileprovider.py, which in turn is derived from
threading.Thread), which would lead me to believe that there's an
error in my code, but the traceback doesn't help much, and I haven't
been able to find any similar problems with google.

Any help would be appreciated.

--
David Roberts
http://da.vidr.cc/


From d at vidr.cc  Fri Jul 24 00:41:01 2009
From: d at vidr.cc (David Roberts)
Date: Fri, 24 Jul 2009 14:41:01 +1000
Subject: OverflowError in RLock.acquire()
In-Reply-To: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>
References: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>
Message-ID: <fe0877110907232141k58f14160r17a23d82fd852714@mail.gmail.com>

I forgot to mention, Python version is 2.6.2.

--
David Roberts
http://da.vidr.cc/



On Fri, Jul 24, 2009 at 14:27, David Roberts<d at vidr.cc> wrote:
> Hi,
>
> I'm trying to port a Python application to Windows, and I'm getting
> the following error (which did not occur when running on Linux):
>
> Exception in thread Thread-4:
> Traceback (most recent call last):
> ?File "C:\Python26\lib\threading.py", line 525, in __bootstrap_inner
> ? ?self.run()
> ?File "C:\Documents and Settings\David\My
> Documents\pyzui\pyzui\tileprovider.py", line 97, in run
> ? ?self.__tilecache[tile_id] = Tile(tile)
> ?File "C:\Documents and Settings\David\My
> Documents\pyzui\pyzui\tilecache.py", line 165, in __setitem__
> ? ?with self.__lock:
> ?File "C:\Python26\lib\threading.py", line 115, in acquire
> ? ?me = current_thread()
> ?File "C:\Python26\lib\threading.py", line 803, in currentThread
> ? ?return _active[_get_ident()]
> OverflowError: can't convert negative value to unsigned long
>
> Where __lock is an RLock object.
>
> The error only occurs for a single class (which is derived from the
> TileProvider class in tileprovider.py, which in turn is derived from
> threading.Thread), which would lead me to believe that there's an
> error in my code, but the traceback doesn't help much, and I haven't
> been able to find any similar problems with google.
>
> Any help would be appreciated.
>
> --
> David Roberts
> http://da.vidr.cc/
>


From timro21 at gmail.com  Fri Jul 24 00:43:48 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 21:43:48 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
	<rmnnj6-f922.ln1@ozzie.tundraware.com>
Message-ID: <b3eb02ce-90a6-4479-a127-c737eabc1c4d@q40g2000prh.googlegroups.com>

Hi Tim, sure, I'm looking at the perfect cuboid problem.

I've just spent a couple of very frustrating hours.  Given that I'm in
my 50's but have the brain of a retarded 3-year-old, can someone
please explain what I have to do to download gmpy to use with
ActivePython 2.6 on a Windows system?  I downloaded (or so I thought)
GMPY 1.04 from http://code.google.com/p/gmpy/ but all the files look
way too small...and then how do I import it into a Python
program...I'm sure I could do this if it wasn't for my extreme
stupidity...


From casevh at gmail.com  Fri Jul 24 01:12:23 2009
From: casevh at gmail.com (casevh)
Date: Thu, 23 Jul 2009 22:12:23 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
	<rmnnj6-f922.ln1@ozzie.tundraware.com>
	<b3eb02ce-90a6-4479-a127-c737eabc1c4d@q40g2000prh.googlegroups.com>
Message-ID: <0fc47aab-eb53-4e0a-be6d-9736883db888@i8g2000pro.googlegroups.com>

On Jul 23, 9:43?pm, timro21 <timr... at gmail.com> wrote:
> Hi Tim, sure, I'm looking at the perfect cuboid problem.
>
> I've just spent a couple of very frustrating hours. ?Given that I'm in
> my 50's but have the brain of a retarded 3-year-old, can someone
> please explain what I have to do to download gmpy to use with
> ActivePython 2.6 on a Windows system? ?I downloaded (or so I thought)
> GMPY 1.04 fromhttp://code.google.com/p/gmpy/but all the files look
> way too small...and then how do I import it into a Python
> program...I'm sure I could do this if it wasn't for my extreme
> stupidity...

You should just download the Windows installer from the Downloads tab.
I would recommend version 1.10 since it should be faster and fixes
some bugs in 1.04. The direct link is

http://gmpy.googlecode.com/files/gmpy-1.10-beta.win32-py2.6.exe

Just run the installer and it should automatically detect your
existing Python installation. The executable is small. ;-)

casevh

p.s. If you're using a 64-bit Windows system, let me know and I'll
step you through the manual process.


From Scott.Daniels at Acm.Org  Fri Jul 24 01:20:27 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Thu, 23 Jul 2009 22:20:27 -0700
Subject: Issue combining gzip and subprocess
In-Reply-To: <m2fxcol75g.fsf@cs.uu.nl>
References: <mailman.3472.1248192725.8015.python-list@python.org>
	<m2eisam153.fsf@cs.uu.nl>
	<2YednUGQxvntgfrXnZ2dnUVZ_hWdnZ2d@pdx.net>
	<m2fxcol75g.fsf@cs.uu.nl>
Message-ID: <XrednR3Zov9Y3_TXnZ2dnUVZ_vGdnZ2d@pdx.net>

Piet van Oostrum wrote:
>>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) schreef:
> ...
>> SDD> Or even:
>> SDD>     proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
>> SDD>     with gzip.open(filename, 'w') as dest:
>> SDD>         for line in iter(proc.stdout, ''):
>> SDD>             f.write(line)
> 
> If it would work.
> 
> 1) with gzip... is not supported in Python < 3.1
> 2) for line in iter(proc.stdout), i.e. no second argument.
> 3) dest <==> f should be the same identifier.
> 
> Lesson: if you post code either: 
> - test it and copy verbatim from your test, or
> - write a disclaimer

Totally chagrined and embarassed.
Chastisement absorbed and acknowledged.

--Scott David Daniels
Scott.Daniels at Acm.Org



From timro21 at gmail.com  Fri Jul 24 01:36:42 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 22:36:42 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
	<rmnnj6-f922.ln1@ozzie.tundraware.com>
	<b3eb02ce-90a6-4479-a127-c737eabc1c4d@q40g2000prh.googlegroups.com>
	<0fc47aab-eb53-4e0a-be6d-9736883db888@i8g2000pro.googlegroups.com>
Message-ID: <4132e60e-f586-42d1-b0fc-460aecf6a474@d9g2000prh.googlegroups.com>


Bloody 'ell - thanks.   :-)




From girish.cfc at gmail.com  Fri Jul 24 02:11:11 2009
From: girish.cfc at gmail.com (Girish)
Date: Thu, 23 Jul 2009 23:11:11 -0700 (PDT)
Subject: Registering DLL
Message-ID: <071d3f78-a14b-4ea1-96fd-0f10d9dc2b80@d36g2000prb.googlegroups.com>

Hello,

I am facing a problem while registering DLL(Dspace.dll).. I am getting
an error saying: "DLLRegisterServer inDspace.dll Failed. Return Code:
0x80040201"

I am using following piece of code to generate DLL:

########################################################

# This setup script builds a single-file Python inprocess COM server.
from distutils.core import setup
import py2exe
import sys

# If run without args, build executables, in quiet mode.
if len(sys.argv) == 1:
    sys.argv.append("py2exe")
    sys.argv.append("-q")

class Target:
    def __init__(self, **kw):
        self.__dict__.update(kw)
        # for the versioninfo resources
        self.version = "1.0"
        self.company_name = "None"
        self.copyright = "None"
        self.name = "API"

interp = Target(
    description = "COM server module",
    # what to build.  For COM servers, the module name (not the
    # filename) must be specified!
    modules = ["Dspace"],
    #script = ["Dspace"],
    # we only want the inproc server.
    create_exe = True,
    )

excludes = ["pywin", "pywin.debugger", "pywin.debugger.dbgcon",
            "pywin.dialogs", "pywin.dialogs.list", 'email.Generator',
'email.Iterators', 'email.Utils']

options = {
    "bundle_files": 1,
    "ascii": 1, # to make a smaller executable, don't include the
encodings
    "compressed": 1, # compress the library archive
    "excludes": excludes, # COM stuff we don't want
    }

setup(
    options = {"py2exe": options},
    zipfile = None, # append zip-archive to the executable.
    com_server = [interp],
    )
################################################################

I am trying to generate a DLL from Python COM server module. I am able
to register the module by running the python code, but when I generate
a DLL and then try to register it using Regsvr32 command, I am getting
above mentioned error

Please help me resolve this issue.

-Girish


From pfeldman at verizon.net  Fri Jul 24 02:35:43 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Thu, 23 Jul 2009 23:35:43 -0700 (PDT)
Subject: len() should always return something
Message-ID: <24639361.post@talk.nabble.com>


Some aspects of the Python design are remarkably clever, while others leave
me perplexed. Here's an example of the latter: Why does len() give an error
when applied to an int or float? len() should always return something; in
particular, when applied to a scalar, it should return a value of 1. Of
course, I can define my own function like this:

def mylen(x):
   if isinstance(x,int) or isinstance(x,float): return 1
   return len(x)

But, this shouldn't be necessary.
-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24639361.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From deets at nospam.web.de  Fri Jul 24 02:57:44 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 08:57:44 +0200
Subject: len() should always return something
In-Reply-To: <mailman.3644.1248417347.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <7ct4b8F29mednU1@mid.uni-berlin.de>

Dr. Phillip M. Feldman schrieb:
> Some aspects of the Python design are remarkably clever, while others leave
> me perplexed. Here's an example of the latter: Why does len() give an error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1. Of
> course, I can define my own function like this:
> 
> def mylen(x):
>    if isinstance(x,int) or isinstance(x,float): return 1
>    return len(x)
> 
> But, this shouldn't be necessary.

Can you show some example of where that is actually making a piece of 
code more elegant?

Diez


From clp2 at rebertia.com  Fri Jul 24 03:02:28 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 00:02:28 -0700
Subject: len() should always return something
In-Reply-To: <24639361.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com>
Message-ID: <50697b2c0907240002i1721d7a4y54d618782ca1a071@mail.gmail.com>

On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Some aspects of the Python design are remarkably clever, while others leave
> me perplexed. Here's an example of the latter: Why does len() give an error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1. Of
> course, I can define my own function like this:
>
> def mylen(x):
> ? if isinstance(x,int) or isinstance(x,float): return 1
> ? return len(x)
>
> But, this shouldn't be necessary.

The problem is that redefining len()/length/size that way would
violate several principles of Python's design (The "Zen" of Python -
http://www.python.org/dev/peps/pep-0020/).

Specifically:
- Explicit is better than implicit.
- Special cases aren't special enough to break the rules.
- Errors should never pass silently.
- In the face of ambiguity, refuse the temptation to guess.

If you'd explain the situation that prompts you to find this
redefinition necessary, I'm sure someone can suggest a better
approach.

Cheers,
Chris
-- 
http://blog.rebertia.com


From __peter__ at web.de  Fri Jul 24 03:07:03 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 09:07:03 +0200
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <h4bmif$cfg$02$1@news.t-online.com>

Dr. Phillip M. Feldman wrote:

> Some aspects of the Python design are remarkably clever, while others
> leave me perplexed. Here's an example of the latter: Why does len() give
> an error when applied to an int or float? len() should always return
> something; in particular, when applied to a scalar, it should return a
> value of 1. Of course, I can define my own function like this:
> 
> def mylen(x):
>    if isinstance(x,int) or isinstance(x,float): return 1
>    return len(x)
> 
> But, this shouldn't be necessary.

Python should not blur the distinction between vectors an scalars like that. 
Instead of trying to be clever you should pass a vector with a single item 
and send mylen() to /dev/null.

On a general note, I think one of Python's strengths is that it consistently 
/avoids/ this kind of cleverness.

A prominent example is the handling of "1" + 1.

Peter



From nick at craig-wood.com  Fri Jul 24 03:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Fri, 24 Jul 2009 02:29:57 -0500
Subject: Looking for os.listdir() generator
References: <mailman.3584.1248352640.8015.python-list@python.org>
	<slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>
	<mailman.3633.1248386949.8015.python-list@python.org>
Message-ID: <slrnh6ini2.m6i.nick@irishsea.home.craig-wood.com>

Christian Heimes <lists at cheimes.de> wrote:
>  Nick Craig-Wood wrote:
> > Christian Heimes <lists at cheimes.de> wrote:
> >>  I'm looking for a generator version of os.listdir() for Python 2.5 and
> >>  newer. I know somebody has worked on it because I've seen a generator
> >>  version in a posting on some list or blog a while ago. I can't find it
> >>  anymore. It seems my Google fu is lacking today. All I can find is a
> >>  very old version of xlistdir. A Cython based solution is appreciated but
> >>  please no ctypes version.
> > 
> > I posted exactly that yesterday I think ;-)
> > 
> > Note that this has a python part as well as a ctypes part because the
> > version of ctypes I used doesn't support generators.  I think the
> > development version does though.
> 
>  Thanks Nick!
> 
>  ctypes? I'm sure you wanted to say Cython :)

Er, yes!

>  If you don't mind I'm going to wrap it up into a nice package and
>  release it on PyPI.

Yes thats fine with me!

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From wilk at flibuste.net  Fri Jul 24 04:04:03 2009
From: wilk at flibuste.net (William Dode)
Date: 24 Jul 2009 08:04:03 GMT
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
	<mailman.3613.1248368814.8015.python-list@python.org>
Message-ID: <4a696af3$0$442$426a74cc@news.free.fr>

On 23-07-2009, Christian Tismer wrote:
> On 7/17/09 4:11 AM, Bearophile wrote:
>> Very good, thank you. I'll try it when I can.
>>
>> Is Psyco3 going to borrow/steal some ideas/code from Unladen Swallow?
>
> Psyco3: nice typo! :-)
>
> Well, I haven't so far found a new idea there that I'd want
> to borrow and did not know from PyPy, before.
> Wasn't the project plan saying the opposite, borrowing
> some ideas from psyco? :-)
> http://code.google.com/p/unladen-swallow/wiki/ProjectPlan

How do you see the futur of psyco when unladen-swallow will grab the 
best of psyco (if they can !) ?

Wait and see ?

Anyway, thanks a lot for your work that we can use NOW !


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From hendrik at microcorp.co.za  Fri Jul 24 04:13:02 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 24 Jul 2009 10:13:02 +0200
Subject: Gedcom and Genealogy
In-Reply-To: <5222a601-a128-4892-9a8d-e1942ac9ce4d@e27g2000yqm.googlegroups.com>
References: <5222a601-a128-4892-9a8d-e1942ac9ce4d@e27g2000yqm.googlegroups.com>
Message-ID: <200907241013.02795.hendrik@microcorp.co.za>

On Friday 24 July 2009 00:14:19 Gordon wrote:
> We have many small libraries in JAVA or Ruby that need to be ported to
> Python.  Actually it's so simple a rewrite is possible too.

Is this:

1 - A question?
2 - A job offer?
3 - A piece of random news?

- Hendrik


From mwawrzyczek at gmail.com  Fri Jul 24 04:35:52 2009
From: mwawrzyczek at gmail.com (marekw2143)
Date: Fri, 24 Jul 2009 01:35:52 -0700 (PDT)
Subject: Adding method from one class to another class or to instance of 
	another class
Message-ID: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>

Hi,

I have one class (A) that has defined method createVars. I would like
to add that method to class B
The code looks like this:


class A(object):
   def createVars(self):
      self.v1 = 1
      self.v2 = 3
      pass

class B(object):
   pass


I don't want to use inheritance (because class A has many methods
defined that class B doesn't need).
When I try the folloowing:


B.createVars = C.createVars
B().createVars()


then the following error occurs:
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unbound method createVars() must be called with A instance
as first argument (got nothing instead)

When I try to add the createVars method to instance of B:

>>> b=B()
>>> b.createVars = new.instancemethod(A.createVars, b, B)
>>> b.createVars
<bound method B.createVars of <__main__.B object at 0x7f6330cc4a90>>
>>> b.createVars()



Then the following error raises:


Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unbound method createVars() must be called with A instance
as first argument (got B instance instead)



How can I solve this problem?

Regards,
Marek


From Slaunger at gmail.com  Fri Jul 24 04:38:37 2009
From: Slaunger at gmail.com (Slaunger)
Date: Fri, 24 Jul 2009 01:38:37 -0700 (PDT)
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
Message-ID: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>

OS: Win XP SP3, 32 bit
Python 2.5.4

Hi I have run into some problems with allocating numpy.memmaps
exceeding and accumulated size of about 2 GB. I have found out that
the real problem relates to numpy.memmap using mmap.mmap

I've written a small test program to illustrate it:

import itertools
import mmap
import os

files = []
mmaps = []
file_names= []
mmap_cap=0
bytes_per_mmap = 100 * 1024 ** 2
try:
    for i in itertools.count(1):
        file_name = "d:/%d.tst" % i
        file_names.append(file_name)
        f = open(file_name, "w+b")
        files.append(f)
        mm = mmap.mmap(f.fileno(), bytes_per_mmap)
        mmaps.append(mm)
        mmap_cap += bytes_per_mmap
        print "Created %d writeable mmaps containing %d MB" % (i,
mmap_cap/(1024**2))

#Clean up
finally:
    print "Removing mmaps..."
    for mm, f, file_name in zip(mmaps, files, file_names):
        mm.close()
        f.close()
        os.remove(file_name)
    print "Done..."


which creates this output

Created 1 writeable mmaps containing 100 MB
Created 2 writeable mmaps containing 200 MB
....
Created 17 writeable mmaps containing 1700 MB
Created 18 writeable mmaps containing 1800 MB
Removing mmaps...
Done...
Traceback (most recent call last):
  File "C:\svn-sandbox\research\scipy\scipy\src\com\terma\kha
\mmaptest.py", line 16, in <module>
    mm = mmap.mmap(f.fileno(), bytes_per_mmap)
WindowsError: [Error 8] Not enough storage is available to process
this command

There is more than 25 GB of free space on drive d: at this stage.

Is it a bug or a "feature" of the 32 bit OS?

I am surprised about it as I have not found any notes about these
kinds of limitations in the documentation.

I am in dire need of these large memmaps for my task, and it is not an
option to change OS due to other constraints in the system.

Is there anything I can do about it?

Best wishes,
Kim


From manu3d at gmail.com  Fri Jul 24 04:55:03 2009
From: manu3d at gmail.com (Emanuele D'Arrigo)
Date: Fri, 24 Jul 2009 01:55:03 -0700 (PDT)
Subject: import vs imp and friends.
References: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
Message-ID: <e5c53078-6878-424a-9996-335ff2fc4427@k19g2000yqn.googlegroups.com>

Christian, Robert, thank you both for the replies, much appreciated.

Manu


From vinay_sajip at yahoo.co.uk  Fri Jul 24 05:14:13 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Fri, 24 Jul 2009 02:14:13 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com> 
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com> 
	<ebe8014b-5323-4cb6-99ec-5612b390130a@d9g2000prh.googlegroups.com>
Message-ID: <61b029e2-494f-4c87-871f-2469a88aaf91@o6g2000yqj.googlegroups.com>

On Jul 24, 4:10?am, Naoki INADA <songofaca... at gmail.com> wrote:
> > Yes! I confused by it.
>
> s/I confused/I am confused/
>
> > "Writing unicode to a file(-like)" is a simple requirement.
> > Does python have any simple resolution for it?
>
> s/resolution/solution/
>

Of course, Python 3 has much better Unicode support:
---------------------------------------------------------------------
C:\Users\Vinay>chcp 1251
Active code page: 1251

C:\Users\Vinay>\python31\python
ActivePython 3.1.0.1 (ActiveState Software Inc.) based on
Python 3.1 (r31:73572, Jun 28 2009, 19:55:39) [MSC v.1500 32 bit
(Intel)] on win
32
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.stdout.encoding
'cp1251'
>>> u = '\u0434\u043e \u0441\u0432\u0438\u0434\u0430\u043d\u0438\u044f'
>>> print(u)
?? ????????
>>> n = sys.stdout.write(u)
?? ????????>>> ^Z
---------------------------------------------------------------------

Regards,


Vinay Sajip


From piet at cs.uu.nl  Fri Jul 24 05:37:21 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 11:37:21 +0200
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>
Message-ID: <m2prbqifqm.fsf@cs.uu.nl>

>>>>> Naoki INADA <songofacandy at gmail.com> (NI) wrote:

>NI> "Writing unicode to a file(-like)" is a simple requirement.
>NI> Does python have any simple resolution for it?

Yes, Python 3 will do this. For Python < 3.0 you will have to use a
codecs wrapper or explicitely do the encoding.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From deets at nospam.web.de  Fri Jul 24 05:38:05 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 11:38:05 +0200
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
In-Reply-To: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
Message-ID: <7ctdo0F28litnU1@mid.uni-berlin.de>

Slaunger schrieb:
> OS: Win XP SP3, 32 bit
> Python 2.5.4
> 
> Hi I have run into some problems with allocating numpy.memmaps
> exceeding and accumulated size of about 2 GB. I have found out that
> the real problem relates to numpy.memmap using mmap.mmap
> 
> I've written a small test program to illustrate it:
> 
> import itertools
> import mmap
> import os
> 
> files = []
> mmaps = []
> file_names= []
> mmap_cap=0
> bytes_per_mmap = 100 * 1024 ** 2
> try:
>     for i in itertools.count(1):
>         file_name = "d:/%d.tst" % i
>         file_names.append(file_name)
>         f = open(file_name, "w+b")
>         files.append(f)
>         mm = mmap.mmap(f.fileno(), bytes_per_mmap)
>         mmaps.append(mm)
>         mmap_cap += bytes_per_mmap
>         print "Created %d writeable mmaps containing %d MB" % (i,
> mmap_cap/(1024**2))
> 
> #Clean up
> finally:
>     print "Removing mmaps..."
>     for mm, f, file_name in zip(mmaps, files, file_names):
>         mm.close()
>         f.close()
>         os.remove(file_name)
>     print "Done..."
> 
> 
> which creates this output
> 
> Created 1 writeable mmaps containing 100 MB
> Created 2 writeable mmaps containing 200 MB
> ....
> Created 17 writeable mmaps containing 1700 MB
> Created 18 writeable mmaps containing 1800 MB
> Removing mmaps...
> Done...
> Traceback (most recent call last):
>   File "C:\svn-sandbox\research\scipy\scipy\src\com\terma\kha
> \mmaptest.py", line 16, in <module>
>     mm = mmap.mmap(f.fileno(), bytes_per_mmap)
> WindowsError: [Error 8] Not enough storage is available to process
> this command
> 
> There is more than 25 GB of free space on drive d: at this stage.
> 
> Is it a bug or a "feature" of the 32 bit OS?

It's a limitation, yes. That's what 64-bit-OSes are for.

> I am surprised about it as I have not found any notes about these
> kinds of limitations in the documentation.
> 
> I am in dire need of these large memmaps for my task, and it is not an
> option to change OS due to other constraints in the system.
> 
> Is there anything I can do about it?

Only by partitioning data yourself, and accessing these partitions. Like 
in the good old days of DOS-programming.

Diez


From piet at cs.uu.nl  Fri Jul 24 05:38:51 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 11:38:51 +0200
Subject: effbot.org broken (WAS: Problems in commands.getoutput(cmd) with
	sox)
References: <mailman.3620.1248378772.8015.python-list@python.org>
Message-ID: <m2ljmeifo4.fsf@cs.uu.nl>

>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:

>CR> On Thu, Jul 23, 2009 at 12:42 PM, Chris Rebert<clp2 at rebertia.com> wrote:
>>> You can use tabnanny to help diagnose the problem:
>>> http://74.125.155.132/search?q=cache:QtxvZm3QDLsJ:effbot.org/librarybook/tabnanny.htm+tabnanny&cd=3&hl=en&ct=clnk&gl=us&client=firefox-a

>CR> Anyone know what's the deal with effbot.org? It seems to be broken at
>CR> present, forcing me to use Google's cached version.
>CR> It's a real shame since it has lots of handy Python info.

Just try again.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From __peter__ at web.de  Fri Jul 24 05:38:57 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 11:38:57 +0200
Subject: Adding method from one class to another class or to instance of
	another class
References: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
Message-ID: <h4bvf7$kj9$00$1@news.t-online.com>

marekw2143 wrote:

> Hi,
> 
> I have one class (A) that has defined method createVars. I would like
> to add that method to class B
> The code looks like this:
> 
> 
> class A(object):
>    def createVars(self):
>       self.v1 = 1
>       self.v2 = 3
>       pass
> 
> class B(object):
>    pass
> 
> 
> I don't want to use inheritance (because class A has many methods
> defined that class B doesn't need).

You can move createVars() into a mixin or common base class:

class M(object):
    def createVars(self): ...

class A(M):
    ...

class B(M)
    ...

> When I try the folloowing:
> 
> 
> B.createVars = C.createVars
> B().createVars()
> 
> 
> then the following error occurs:
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unbound method createVars() must be called with A instance
> as first argument (got nothing instead)
> 
> When I try to add the createVars method to instance of B:
> 
>>>> b=B()
>>>> b.createVars = new.instancemethod(A.createVars, b, B)
>>>> b.createVars
> <bound method B.createVars of <__main__.B object at 0x7f6330cc4a90>>
>>>> b.createVars()
> 
> 
> 
> Then the following error raises:
> 
> 
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unbound method createVars() must be called with A instance
> as first argument (got B instance instead)
> 
> 
> 
> How can I solve this problem?

>>> class A(object):
...     def create_vars(self):
...             self.x = 42
...
>>> class B(object): pass
...
>>> B.create_vars = A.create_vars.im_func
>>> b = B()
>>> b.create_vars()
>>> b.x
42

An alternative I find a bit cleaner:

>>> def create_vars(self): self.x = 42
...
>>> class A(object):
...     create_vars = create_vars
...
>>> class B(object):
...     create_vars = create_vars
...
>>> b = B()
>>> b.create_vars()
>>> b.x
42

Peter




From gagsl-py2 at yahoo.com.ar  Fri Jul 24 05:47:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 24 Jul 2009 06:47:37 -0300
Subject: available formats and params for Image.save()
References: <4a6833dd$0$22599$426a34cc@news.free.fr>
Message-ID: <op.uxkf5nv7x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 06:56:45 -0300, News123 <news123 at free.fr> escribi?:

> Somehow I have difficulties reading the documentation for PIL (Image)
>
> Is there an easy way to know which formats are supported and what their
> names are?

py> import PIL
py> from PIL import Image
py> Image.ID
[]
py> Image.init()
py> Image.ID
['PNG', 'ARG', 'BMP', 'BUFR', 'CUR', 'PCX', 'DCX', 'EPS', 'FITS', 'FLI',  
'FPX',
'GBR', 'GIF', 'GRIB', 'HDF5', 'ICNS', 'ICO', 'IM', 'IMT', 'IPTC', 'JPEG',  
'MCIDA
S', 'TIFF', 'MIC', 'MPEG', 'MSP', 'PCD', 'PIXAR', 'PPM', 'PSD', 'SGI',  
'SPIDER',
  'SUN', 'TGA', 'WBMP', 'WMF', 'XBM', 'XPM', 'XVTHUMB']
py> Image.OPEN.keys()
['PCX', 'ICNS', 'HDF5', 'SUN', 'MIC', 'EPS', 'MSP', 'FLI', 'FITS', 'GBR',  
'WBMP'
, 'PCD', 'PIXAR', 'BUFR', 'PPM', 'WMF', 'SGI', 'BMP', 'TGA', 'DCX', 'ICO',  
'CUR'
, 'XPM', 'TIFF', 'JPEG', 'SPIDER', 'GIF', 'GRIB', 'IM', 'IMT', 'IPTC',  
'FPX', 'X
BM', 'MPEG', 'PSD', 'ARG', 'XVTHUMB', 'PNG', 'MCIDAS']
py> Image.SAVE.keys()
['XBM', 'PCX', 'SPIDER', 'HDF5', 'TIFF', 'BUFR', 'EPS', 'JPEG', 'MSP',  
'GRIB', '
GIF', 'BMP', 'IM', 'PPM', 'PDF', 'FITS', 'PALM', 'WBMP', 'WMF', 'PNG']

> Is there an easy way to know which parameters are supported by
> Image.save(). How can I list them where are they documented?

That depends on the format being used. The PIL handbook lists the standard  
formats used and their parameters:
http://www.pythonware.com/library/pil/handbook/index.htm

> I'm at a complete loss at finding out what parameters the save function
> accepts for saving a JPG file or a PNG file

http://www.pythonware.com/library/pil/handbook/format-jpeg.htm

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 24 06:06:29 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 24 Jul 2009 07:06:29 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
	<EgE9m.507$646.499@nwrddc01.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
	<h4av5n$p1l$1@panix3.panix.com>
Message-ID: <op.uxkg03exx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 21:27:35 -0300, Aahz <aahz at pythoncraft.com> escribi?:
> In article <mailman.3561.1248307942.8015.python-list at python.org>,
> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>>
>> NLMPI
>
> What?

IHNFI

-- 
Gabriel Genellina



From amrita at iisermohali.ac.in  Fri Jul 24 06:20:11 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Fri, 24 Jul 2009 15:50:11 +0530 (IST)
Subject: how to get no value
Message-ID: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>


Hi,

I have a file having lines:-

48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
85 ALA H = 8.60 N =  CA =  HA = 4.65 C =

Now i want to make two another file in which i want to put those lines for
which C is missing and another one for which N,CA and C all are missing,

I tried in this way:
import re
f = open('chem.txt')
for line in f:
     if re.search('C = ',''):
        print line

but i am not getting the desired output.




Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From lpmelo at ualg.pt  Fri Jul 24 06:21:30 2009
From: lpmelo at ualg.pt (Luis Pedro Almeida)
Date: Fri, 24 Jul 2009 11:21:30 +0100
Subject: Convert points to polygon shapefile
Message-ID: <20090724101638.E93B414B2A@smtp3.ualg.pt>

Dear all,



I would like to know how to convert a list of points into a polygon 
shapefile (esri).



Thanks!



Best regards,



Luis Pedro Almeida



From gagsl-py2 at yahoo.com.ar  Fri Jul 24 06:24:52 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 24 Jul 2009 07:24:52 -0300
Subject: OverflowError in RLock.acquire()
References: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>
Message-ID: <op.uxkhvqxgx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 24 Jul 2009 01:27:10 -0300, David Roberts <d at vidr.cc> escribi?:

> I'm trying to port a Python application to Windows, and I'm getting
> the following error (which did not occur when running on Linux):
>
> Exception in thread Thread-4:
>   File "C:\Python26\lib\threading.py", line 803, in currentThread
>     return _active[_get_ident()]
> OverflowError: can't convert negative value to unsigned long

Looks like a bug in the thread module - you should report it at  
http://bugs.python.org

-- 
Gabriel Genellina



From piet at cs.uu.nl  Fri Jul 24 06:46:14 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 12:46:14 +0200
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
Message-ID: <m2hbx2icjt.fsf@cs.uu.nl>

>>>>> Slaunger <Slaunger at gmail.com> (S) wrote:

>S> OS: Win XP SP3, 32 bit
>S> Python 2.5.4

>S> Hi I have run into some problems with allocating numpy.memmaps
>S> exceeding and accumulated size of about 2 GB. I have found out that
>S> the real problem relates to numpy.memmap using mmap.mmap

On Windows XP the virtual address space of a process is limited to 2 GB
unless the /3GB switch is used in the Boot.ini file.
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From darcy at druid.net  Fri Jul 24 06:56:03 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Fri, 24 Jul 2009 06:56:03 -0400
Subject: how to get no value
In-Reply-To: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
References: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
Message-ID: <20090724065603.cd758a39.darcy@druid.net>

On Fri, 24 Jul 2009 15:50:11 +0530 (IST)
amrita at iisermohali.ac.in wrote:
> but i am not getting the desired output.

Show us what output you got and what you desired.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From deets at nospam.web.de  Fri Jul 24 06:56:16 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 12:56:16 +0200
Subject: how to get no value
In-Reply-To: <mailman.3649.1248430821.8015.python-list@python.org>
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <7ctiaiF1vrcvpU1@mid.uni-berlin.de>

amrita at iisermohali.ac.in schrieb:
> Hi,
> 
> I have a file having lines:-
> 
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
> 
> Now i want to make two another file in which i want to put those lines for
> which C is missing and another one for which N,CA and C all are missing,
> 
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
> 
> but i am not getting the desired output.


Gosh. Must be groundhog-day. Again.

And there is me thinking that my job could be endangered by cheap & 
qualified indian soft-workers - can't be to many of them around if the 
OP doesn't get a hold of one for the better part of a month now. Must be 
one of those management myths they tell you to scare you into a less 
well paid contract...

Diez


From beni.cherniavsky at gmail.com  Fri Jul 24 07:13:09 2009
From: beni.cherniavsky at gmail.com (Beni Cherniavsky)
Date: Fri, 24 Jul 2009 04:13:09 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com> 
	<mailman.3511.1248244497.8015.python-list@python.org>
Message-ID: <9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>

On Jul 22, 9:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>
> > My guess is that it was probably for optimization reasons long ago.
> > I've never heard a *good* reason why Python needs both.
>
> The good reason is the immutability, which lets you use
> a tuple as a dict key. ?
>
On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>
> > My guess is that it was probably for optimization reasons long ago.
> > I've never heard a *good* reason why Python needs both.
>
> The good reason is the immutability, which lets you use
> a tuple as a dict key.
>
The *technical* reason is immutability for dict keys.
Dict could allow mutable objects as keys by comparing *by value*,
making a copy on insertion and hashing the current value on lookup.
Prior art: the 2.3 sets module allows mutable Sets as elements in
Sets, by making ImmutableSet copies on insertion, and hashing Sets as
if they are temporarily immutable on lookup.

This inspired PEP 351 and ambitious proposals to expand the approach
to all Python with a copy-on-write scheme.  But these ideas were
rejected, and the 2.4 builtin sets only allow frozenset elements.
Half the reason is technical: copy-on-write and harder than it sounds,
and without it you pay a performance price.

But the deeper reason is style: immutable types are convenient!
The allow a pure-functional style of code, which can be simpler.
Of course, sometimes an imperative style is simpler.  Depends on the
problem.

My rule of thumb:
- Use mutable lists when you are likely to modify individual elements.
- Use immutable tuples when you are likely to replace the whole thing.

(In practice, this boils down to similar usage to the "official" rule
of thumb that lists are for homogenous data, and tuples for
heterogenous records.)


From d at vidr.cc  Fri Jul 24 07:29:44 2009
From: d at vidr.cc (David Roberts)
Date: Fri, 24 Jul 2009 21:29:44 +1000
Subject: OverflowError in RLock.acquire()
In-Reply-To: <op.uxkhvqxgx6zn5v@lepton.softlabbsas.com.ar>
References: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com> 
	<op.uxkhvqxgx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <fe0877110907240429w66aa63dhf40e887d23c373a9@mail.gmail.com>

Done: http://bugs.python.org/issue6562

--
David Roberts
http://da.vidr.cc/



On Fri, Jul 24, 2009 at 20:24, Gabriel Genellina<gagsl-py2 at yahoo.com.ar> wrote:
> En Fri, 24 Jul 2009 01:27:10 -0300, David Roberts <d at vidr.cc> escribi?:
>
>> I'm trying to port a Python application to Windows, and I'm getting
>> the following error (which did not occur when running on Linux):
>>
>> Exception in thread Thread-4:
>> ?File "C:\Python26\lib\threading.py", line 803, in currentThread
>> ? ?return _active[_get_ident()]
>> OverflowError: can't convert negative value to unsigned long
>
> Looks like a bug in the thread module - you should report it at
> http://bugs.python.org
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From piet at cs.uu.nl  Fri Jul 24 07:48:09 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 13:48:09 +0200
Subject: how to get no value
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <m2d47qi9om.fsf@cs.uu.nl>

>>>>> amrita at iisermohali.ac.in (a) a ?crit:

>a> Hi,

>a> I have a file having lines:-

>a> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
>a> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
>a> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =

>a> Now i want to make two another file in which i want to put those lines for
>a> which C is missing and another one for which N,CA and C all are missing,

>a> I tried in this way:
>a> import re
>a> f = open('chem.txt')
>a> for line in f:
>a>      if re.search('C = ',''):
>a>         print line

>a> but i am not getting the desired output.

You never look in the lines you read. 
    if re.search('C = ',''): should be
    if re.search('C = ', line):

Do you really think before you write your code? Or look at it after you
have written it? 

Sorry if I offend you but you give the impression of just trying some
more or less random stuff and then asking here if it doesn't give the
required result.

That's not the attitude of a researcher, unless your definition of
research is 'asking on Usenet'.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From pdpinheiro at gmail.com  Fri Jul 24 08:08:21 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Fri, 24 Jul 2009 05:08:21 -0700 (PDT)
Subject: Convert points to polygon shapefile
References: <mailman.3651.1248432554.8015.python-list@python.org>
Message-ID: <dd1e7139-0011-4e7c-8d9e-6471d8348564@o32g2000yqm.googlegroups.com>

On Jul 24, 11:21?am, Luis Pedro Almeida <lpm... at ualg.pt> wrote:
> Dear all,
>
> I would like to know how to convert a list of points into a polygon
> shapefile (esri).
>
> Thanks!
>
> Best regards,
>
> Luis Pedro Almeida

I think you'd be better served by asking this question in a newsgroup
dedicated to GIS software (I'm guessing that's the ESRI you meant).
Still, what you want is to find the file format specification, and
implement it.


From piet at cs.uu.nl  Fri Jul 24 08:14:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 14:14:27 +0200
Subject: Convert points to polygon shapefile
References: <mailman.3651.1248432554.8015.python-list@python.org>
Message-ID: <m28wiei8gs.fsf@cs.uu.nl>

>>>>> Luis Pedro Almeida <lpmelo at ualg.pt> (LPA) wrote:

>LPA> Dear all,
>LPA> I would like to know how to convert a list of points into a
>LPA> polygon shapefile (esri).

http://lmgtfy.com/?q=esri+shapefile+Python
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From davea at ieee.org  Fri Jul 24 08:25:17 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 24 Jul 2009 08:25:17 -0400
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
In-Reply-To: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
Message-ID: <4A69A82D.8090301@ieee.org>

Slaunger wrote:
> OS: Win XP SP3, 32 bit
> Python 2.5.4
>
> Hi I have run into some problems with allocating numpy.memmaps
> exceeding and accumulated size of about 2 GB. I have found out that
> the real problem relates to numpy.memmap using mmap.mmap
>
> I've written a small test program to illustrate it:
>
> import itertools
> import mmap
> import os
>
> files = []
> mmaps = []
> file_names= []
> mmap_cap=0
> bytes_per_mmap = 100 * 1024 ** 2
> try:
>     for i in itertools.count(1):
>         file_name = "d:/%d.tst" % i
>         file_names.append(file_name)
>         f = open(file_name, "w+b")
>         files.append(f)
>         mm = mmap.mmap(f.fileno(), bytes_per_mmap)
>         mmaps.append(mm)
>         mmap_cap += bytes_per_mmap
>         print "Created %d writeable mmaps containing %d MB" % (i,
> mmap_cap/(1024**2))
>
> #Clean up
> finally:
>     print "Removing mmaps..."
>     for mm, f, file_name in zip(mmaps, files, file_names):
>         mm.close()
>         f.close()
>         os.remove(file_name)
>     print "Done..."
>
>
> which creates this output
>
> Created 1 writeable mmaps containing 100 MB
> Created 2 writeable mmaps containing 200 MB
> ....
> Created 17 writeable mmaps containing 1700 MB
> Created 18 writeable mmaps containing 1800 MB
> Removing mmaps...
> Done...
> Traceback (most recent call last):
>   File "C:\svn-sandbox\research\scipy\scipy\src\com\terma\kha
> \mmaptest.py", line 16, in <module>
>     mm = mmap.mmap(f.fileno(), bytes_per_mmap)
> WindowsError: [Error 8] Not enough storage is available to process
> this command
>
> There is more than 25 GB of free space on drive d: at this stage.
>
> Is it a bug or a "feature" of the 32 bit OS?
>
> I am surprised about it as I have not found any notes about these
> kinds of limitations in the documentation.
>
> I am in dire need of these large memmaps for my task, and it is not an
> option to change OS due to other constraints in the system.
>
> Is there anything I can do about it?
>
> Best wishes,
> Kim
>
>   
It's not a question of how much disk space there is, but how much 
virtual space 32 bits can address.  2**32 is about 4 gig, and Windows XP 
reserves about half of that for system use.  Presumably a 64 bit OS 
would have a much larger limit.

Years ago I worked on Sun Sparc system which had much more limited 
shared memory access, due to hardware limitations.  So 2gig seems pretty 
good to me.

There is supposed to be a way to tell the Windows OS to only use 1 gb of 
virtual space, leaving 3gb for application use.  But there are some 
limitations, and I don't recall what they are.  I believe it has to be 
done globally (probably in Boot.ini), rather than per process.  And some 
things didn't work in that configuration.

DaveA



From jeanmichel at sequans.com  Fri Jul 24 08:34:23 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 24 Jul 2009 14:34:23 +0200
Subject: doted filenames in import statements
In-Reply-To: <h47fko$tqp$1@ger.gmane.org>
References: <mailman.3488.1248212574.8015.python-list@python.org>	<m2prbtllen.fsf@cs.uu.nl>	<4A670313.8040204@sequans.com>
	<h47fko$tqp$1@ger.gmane.org>
Message-ID: <4A69AA4F.9060707@sequans.com>

Terry Reedy wrote:
> Jean-Michel Pichavant wrote:
>> Piet van Oostrum wrote:
>>>
>>> [snip]
>>>
>>>> JP> file = "/home/dsp/4.6.0.0/test.py"
>>>> JP> test = __import__(file)
>>>> JP> => no module name blalalal found.
>>>
>>>
>>>> JP> Any suggestion ? I tried multiple escape technics without any 
>>>> success.
>>>
>>> Rightly so.
>>>
>>> I think the best would be to add the directory to sys.path 
>>> sys.path.add('/home/dsp/4.6.0.0')
>>> and then
>>> __import__('test', ... ) 
>>
>> I see. My problem is that a have to import 2 different files having 
>> de same name. In the same name space I have 2 objects from 2 
>> different software branches, let's say 4.6.0 and 4.6.1.
>> The first object shall import 4.6.0/orb.py and the second one 
>> 4.6.1/orb.py.
>>
>> If I add 4.6.1 to sys.path, the import statement will look like:
>> self._orb = __import__('orb')
>> The problem is, python wil assume orb is already imported and will 
>> assign the module from the 4.6.0 branch to my 4.6.1 object.
>>
>> Do I have to mess up with sys.modules keys to make python import the 
>> correct file ? Is there a standard/proper way to do that ?
>
> If you make the directory names into proper identifiers like v460 and 
> v461 and add __init__.py to each to make them packages and have both 
> on search path, then
>
> import v460.orb #or import v460.orb as orb460
> import v461.orb #or import v460.orb as orb461
>
> will get you both. One way or another, they have to get different 
> names within Python.
>
> Terry Jan Reedy
>

I finally had to write my own import statement as I prefered to 
manipulate the python objects instead of manipulating third party files. 
Basically when importing 'file.py' it records it in sys.modules as 
sys.modules['__magic_word_file''] and then I remove the standard 
reference. This allows me to import file.py again, but with a totally 
different path. (path is temporarily added to sys.path)

JM


From sanne at kortec.nl  Fri Jul 24 08:34:53 2009
From: sanne at kortec.nl (Sanne Korzec)
Date: Fri, 24 Jul 2009 14:34:53 +0200
Subject: trouble with wrapping a c program
Message-ID: <20090724123458.TOWM14607.viefep17-int.chello.at@edge02.upc.biz>

Hi Mailing,

 

I am using a c program, which first initializes for some seconds and then
waits for user input (keyboard) to type something. When enter is pressed the
c program continues. 

 

I have wrapped this program in a python script, which starts the c program.
To start the c program, there are many options in python e.g.

 

Os.system os.popen or subprocess.popen 

To me there does not seem to be a difference for starting the program. They
all work well.

 

However the problem occurs when I want to input data during this c program. 

 

Using the keyboard and then enter in the c program prompt works, but I wish
to do this from the python script by sending the string from the python
script.

 

I am able to print the string from python with a print command or with a
stdout.write command. But this simply prints it to the prompt, the c program
does nothing with this printed string.

 

Is there a way to pipe, stream, or send this string to the running c
program?

 

All tutorials about piping I have read, seem to have to wait for the process
to finish. Or need the stdin string before starting the program.

Note that the c program is not finished when the input is needed, so I
cannot use subprocess.call or wait.

It is possible to give the user input in advance, but I do not want this,
because this makes everything much slower!

I really would like to do this during/while the c program is running.

 

I have created a thread and a small xmlrpc server for this and this works
fine. However I cannot seem to pass the string.

 

Here is a small fragment of my code:

 

#initialization

cmd = [a list of my program and arguments]

subprocess.Popen(cmd)   #starts the c program

 

 

#somewhere along the way

Send_string(str):

            

#Sys.stdin = str

            #subprocess.stdin = str

 

 

I have spent the entire night trying to get this to work, but I can't seem
to get it right. Any help is much appreciated. Also, if anybody could
explain me where the fuck-up in my brain is, I would be very happy..

 

Sanne              

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090724/46e39bd6/attachment.html>

From doetoe at gmail.com  Fri Jul 24 08:38:00 2009
From: doetoe at gmail.com (Utpal Sarkar)
Date: Fri, 24 Jul 2009 05:38:00 -0700 (PDT)
Subject: non-owning references?
Message-ID: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>

Hi,

I'm not sure the subject describes what I'm looking for, but the
question is the following:
Is there a way I can tell a variable that the object it is pointing
too is not owned by it, in the sense that if it is the only reference
to the object it can be garbage collected?
I want this for what is essentially a singleton class, so that on
first instantiation the object is created and a reference is kept in
the class, that is used to return the same object in subsequent
instantiations. When all instances go out of scope, the reference in
the class is still there, preventing it from being garbage collected,
but since the instance can be huge, I would like it to be.

Thanks,

Utpal


From __peter__ at web.de  Fri Jul 24 08:52:07 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 14:52:07 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
Message-ID: <h4capd$sn3$01$1@news.t-online.com>

Utpal Sarkar wrote:

> Is there a way I can tell a variable that the object it is pointing
> too is not owned by it, in the sense that if it is the only reference
> to the object it can be garbage collected?

http://docs.python.org/library/weakref.html




From gh at ghaering.de  Fri Jul 24 09:00:43 2009
From: gh at ghaering.de (=?ISO-8859-1?Q?Gerhard_H=E4ring?=)
Date: Fri, 24 Jul 2009 15:00:43 +0200
Subject: non-owning references?
In-Reply-To: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
Message-ID: <h4cb9r$b52$1@ger.gmane.org>

Utpal Sarkar wrote:
> Hi,
> [...]

You're looking for the weakref module.

What you're describing there sounds like a nice exercise, but I cannot
imagine why you'd really need to clean it up, if it really is a singleton.

-- Gerhard



From ben+python at benfinney.id.au  Fri Jul 24 09:06:34 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 24 Jul 2009 23:06:34 +1000
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
Message-ID: <87d47q5ixx.fsf@benfinney.id.au>

Utpal Sarkar <doetoe at gmail.com> writes:

> Is there a way I can tell a variable that the object it is pointing
> too is not owned by it, in the sense that if it is the only reference
> to the object it can be garbage collected?

Python doesn't have ?pointers?, and doesn't really have ?variables?
either, at least not how many other languages use that term.

What it does have is references to objects
<URL:http://effbot.org/zone/python-objects.htm>.

> on first instantiation the object is created and a reference is kept
> in the class, that is used to return the same object in subsequent
> instantiations. When all instances go out of scope, the reference in
> the class is still there, preventing it from being garbage collected,
> but since the instance can be huge, I would like it to be.

What you are asking for is called a ?weak reference? and is provided
by the ?weakref? module <URL:http://docs.python.org/library/weakref>.

-- 
 \      ?Patience, n. A minor form of despair, disguised as a virtue.? |
  `\                   ?Ambrose Bierce, _The Devil's Dictionary_, 1906 |
_o__)                                                                  |
Ben Finney


From doetoex at gmail.com  Fri Jul 24 09:18:48 2009
From: doetoex at gmail.com (Doetoe)
Date: Fri, 24 Jul 2009 06:18:48 -0700 (PDT)
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
Message-ID: <14f1729b-9035-417f-a725-3deaa9408a69@c2g2000yqi.googlegroups.com>

On Jul 24, 3:06?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Utpal Sarkar <doe... at gmail.com> writes:
> > Is there a way I can tell a variable that the object it is pointing
> > too is not owned by it, in the sense that if it is the only reference
> > to the object it can be garbage collected?
>
> Python doesn't have ?pointers?, and doesn't really have ?variables?
> either, at least not how many other languages use that term.
>
> What it does have is references to objects
> <URL:http://effbot.org/zone/python-objects.htm>.
>
> > on first instantiation the object is created and a reference is kept
> > in the class, that is used to return the same object in subsequent
> > instantiations. When all instances go out of scope, the reference in
> > the class is still there, preventing it from being garbage collected,
> > but since the instance can be huge, I would like it to be.
>
> What you are asking for is called a ?weak reference? and is provided
> by the ?weakref? module <URL:http://docs.python.org/library/weakref>.
>
> --
> ?\ ? ? ??Patience, n. A minor form of despair, disguised as a virtue.? |
> ? `\ ? ? ? ? ? ? ? ? ? ?Ambrose Bierce, _The Devil's Dictionary_, 1906 |
> _o__) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?|
> Ben Finney

Thanks to the three of you. This is precisely what I needed!
Gerhard, the reason I need to clean it up is that it is a lazy data
structure that can grow to arbitrary size. When it is not needed
anymore it would still remain in memory.

Utpal


From breamoreboy at yahoo.co.uk  Fri Jul 24 09:50:33 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 24 Jul 2009 14:50:33 +0100
Subject: how to get no value
In-Reply-To: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
References: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
Message-ID: <h4ce4v$kfe$1@ger.gmane.org>

amrita at iisermohali.ac.in wrote:
> Hi,
> 
> I have a file having lines:-
> 
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
> 
> Now i want to make two another file in which i want to put those lines for
> which C is missing and another one for which N,CA and C all are missing,
> 
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
> 
> but i am not getting the desired output.
> 
> 
> 
> 
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
> 
Try writing correct rather than incorrect code.  Or as has been 
repeatedly stated get somone from your CS department to help.


-- 

Kindest regards.

Mark Lawrence.



From hniksic at xemacs.org  Fri Jul 24 09:55:45 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Fri, 24 Jul 2009 15:55:45 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
Message-ID: <87fxcm5gny.fsf@busola.homelinux.net>

Ben Finney <ben+python at benfinney.id.au> writes:

> Utpal Sarkar <doetoe at gmail.com> writes:
>
>> Is there a way I can tell a variable that the object it is pointing
>> too is not owned by it, in the sense that if it is the only reference
>> to the object it can be garbage collected?
>
> Python doesn't have ?pointers?, and doesn't really have ?variables?
> either, at least not how many other languages use that term.

The OP didn't use the term "pointer", but the word "pointing", which
makes sense in the context.  The term "variable" is used in the Python
language reference and elsewhere, and is quite compatible with how other
popular languages (Java, PHP, Lisp, ...) use it.  Please stop
complaining about valid terminology; it is not helpful.


From invalid at invalid  Fri Jul 24 09:57:02 2009
From: invalid at invalid (Grant Edwards)
Date: Fri, 24 Jul 2009 08:57:02 -0500
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>

On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>
> Some aspects of the Python design are remarkably clever, while
> others leave me perplexed. Here's an example of the latter:
> Why does len() give an error when applied to an int or float?
> len() should always return something; in particular, when
> applied to a scalar, it should return a value of 1.

If len(7) returned a value of 1, then wouldn't one expect 7[0]
to be valid?  It isn't, so you'd then have to redefine all
types so that they are sequences that can be indexed.  Sounds
like a big mess to me...

[Are there types for which len() returns a value that can't be
indexed?]

-- 
Grant Edwards                   grante             Yow! It's the RINSE CYCLE!!
                                  at               They've ALL IGNORED the
                               visi.com            RINSE CYCLE!!


From timlee126 at yahoo.com  Fri Jul 24 10:03:22 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 24 Jul 2009 07:03:22 -0700 (PDT)
Subject: Popen
Message-ID: <896055.35192.qm@web63101.mail.re1.yahoo.com>


Hi,
I wonder if I use Popen, the parent process will wait for the child process to finish or continue without waiting?
Thanks and regards!


      


From invalid at invalid  Fri Jul 24 10:10:29 2009
From: invalid at invalid (Grant Edwards)
Date: Fri, 24 Jul 2009 09:10:29 -0500
Subject: how to get no value
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <MOKdne1B6L9IXfTXnZ2dnUVZ_qqdnZ2d@posted.visi>

On 2009-07-24, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:
>
> Hi,
>
> I have a file having lines:-
>
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
>
> Now i want to make two another file in which i want to put
> those lines for which C is missing and another one for which
> N,CA and C all are missing,
>
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
>
> but i am not getting the desired output.

I've told you before: don't use regular expressions (e.g. the
"re" module).  Stop using regular expressions now.  Regular
expressions are way beyond your capabilities.  

Use simple operations like split() and "in":

  f = open('chem.txt')
  for line in f:
    if "C = " in line:
      print line
      
You really need to work through a Python tutorial or two:

  http://docs.python.org/tutorial/
  http://www.greenteapress.com/thinkpython/thinkpython.html

Better yet, take an couple introductory programming courses.

I'm a bit surprised that one could become a "Research Fellow"
in a scientific field without taking any programming courses.

-- 
Grant Edwards                   grante             Yow! I'm also against
                                  at               BODY-SURFING!!
                               visi.com            


From rhodri at wildebst.demon.co.uk  Fri Jul 24 10:11:40 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 15:11:40 +0100
Subject: len() should always return something
In-Reply-To: <4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
Message-ID: <op.uxksdqn1a8ncjz@gnudebst>

On Fri, 24 Jul 2009 14:57:02 +0100, Grant Edwards <invalid at invalid> wrote:

> On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>>
>> Some aspects of the Python design are remarkably clever, while
>> others leave me perplexed. Here's an example of the latter:
>> Why does len() give an error when applied to an int or float?
>> len() should always return something; in particular, when
>> applied to a scalar, it should return a value of 1.
>
> If len(7) returned a value of 1, then wouldn't one expect 7[0]
> to be valid?  It isn't, so you'd then have to redefine all
> types so that they are sequences that can be indexed.  Sounds
> like a big mess to me...
>
> [Are there types for which len() returns a value that can't be
> indexed?]
>

Dictionaries.

Which doesn't make your point less valid.  In fact I'd go so
far as to argue that what len() gives you is the number of
items in a container, so len(7) should return 0.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Fri Jul 24 10:21:36 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 15:21:36 +0100
Subject: non-owning references?
In-Reply-To: <87fxcm5gny.fsf@busola.homelinux.net>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
Message-ID: <op.uxksuaifa8ncjz@gnudebst>

On Fri, 24 Jul 2009 14:55:45 +0100, Hrvoje Niksic <hniksic at xemacs.org>  
wrote:

> Ben Finney <ben+python at benfinney.id.au> writes:
>
>> Utpal Sarkar <doetoe at gmail.com> writes:
>>
>>> Is there a way I can tell a variable that the object it is pointing
>>> too is not owned by it, in the sense that if it is the only reference
>>> to the object it can be garbage collected?
>>
>> Python doesn't have ?pointers?, and doesn't really have ?variables?
>> either, at least not how many other languages use that term.
>
> The OP didn't use the term "pointer", but the word "pointing", which
> makes sense in the context.  The term "variable" is used in the Python
> language reference and elsewhere, and is quite compatible with how other
> popular languages (Java, PHP, Lisp, ...) use it.

Only superficially.  Treating Python variables the same as C variables
(say) is one of the classic ways that newbies come unstuck when mutable
objects appear on the scene.  While the OP appears to have the right idea,
your "correction" here could be quite misleading.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From pruebauno at latinmail.com  Fri Jul 24 10:45:21 2009
From: pruebauno at latinmail.com (nn)
Date: Fri, 24 Jul 2009 07:45:21 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3636.1248390216.8015.python-list@python.org>
Message-ID: <c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>

On Jul 23, 7:03?pm, Dave Angel <da... at ieee.org> wrote:
> Mark Tarver wrote:
> > I have a very strange error. ?I have two test python files test.py and
> > python.py which contain the following code
>
> > #!/usr/bin/python
> > print "Content-type: text/html"
> > print
> > print "<html>"
> > print "<center>Hello, Linux.com!</center>"
> > print "</html>"
>
> > One file (test.py) works; you call it up and it shows a web page with
>
> > Hello, Linux.com
>
> > The other fails with a server configuration error. ?Both are running
> > under Linux, same server, same permissions. ?Running a character scan
> > shows that both files contain the same printable characters and are
> > therefore typographically identical. ? They are absolutely the same.
>
> > The only hint at a difference I can see is that my ftp program says
> > the files are of unequal lengths. ?test.py is 129 bytes long.
> > python.py 134 bytes long.
>
> > A zipped folder containing both files is at
>
> >www.lambdassociates.org/weird.zip
>
> > Any ideas welcome.
>
> > Mark
>
> Easiest explanation is that python.py has Windows-style newlines. ?In
> other words, each line ends with 0d0a, rather than the Unix convention
> of 0a.
>
> If your server is Unix-based, it can't handle that first line, since it
> has an illegal character (0d) following the
>
> #!/usr/bin/python
>
> line. ?Convert it to Unix line-endings.
>
> DaveA

Use dos2unix for conversion of the longer file and try again:

http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm


From dickinsm at gmail.com  Fri Jul 24 10:45:40 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Fri, 24 Jul 2009 07:45:40 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org> 
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
Message-ID: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>

On Jul 24, 3:11?pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
wrote:
> Which doesn't make your point less valid. ?In fact I'd go so
> far as to argue that what len() gives you is the number of
> items in a container, so len(7) should return 0.

Nah.  7 contains three bits, so len(7) should *clearly* return 3.

Mark


From user at example.net  Fri Jul 24 10:50:03 2009
From: user at example.net (superpollo)
Date: Fri, 24 Jul 2009 16:50:03 +0200
Subject: len() should always return something
In-Reply-To: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
Message-ID: <4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>

Mark Dickinson wrote:
> On Jul 24, 3:11 pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
> wrote:
> 
>>Which doesn't make your point less valid.  In fact I'd go so
>>far as to argue that what len() gives you is the number of
>>items in a container, so len(7) should return 0.
> 
> 
> Nah.  7 contains three bits, so len(7) should *clearly* return 3.

and len("7") must return 8, by the same token... but wait!

 >>> len("7")
1
 >>>

my python installation must me outdated ;-)

bye



From deets at nospam.web.de  Fri Jul 24 10:51:12 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 16:51:12 +0200
Subject: len() should always return something
In-Reply-To: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
Message-ID: <7cu030F295totU1@mid.uni-berlin.de>

Mark Dickinson schrieb:
> On Jul 24, 3:11 pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
> wrote:
>> Which doesn't make your point less valid.  In fact I'd go so
>> far as to argue that what len() gives you is the number of
>> items in a container, so len(7) should return 0.
> 
> Nah.  7 contains three bits, so len(7) should *clearly* return 3.

But it contains a minimum of 32 bits! And why are you treating ones as 
special over zeros? I thought the times of BitRacism were finally over...

Diez


From kushal.kumaran+python at gmail.com  Fri Jul 24 10:58:49 2009
From: kushal.kumaran+python at gmail.com (Kushal Kumaran)
Date: Fri, 24 Jul 2009 20:28:49 +0530
Subject: Popen
In-Reply-To: <896055.35192.qm@web63101.mail.re1.yahoo.com>
References: <896055.35192.qm@web63101.mail.re1.yahoo.com>
Message-ID: <1e364c4e0907240758k753f8653o225ac97e92fd2eea@mail.gmail.com>

On Fri, Jul 24, 2009 at 7:33 PM, Tim<timlee126 at yahoo.com> wrote:
>
> Hi,
> I wonder if I use Popen, the parent process will wait for the child process to finish or continue without waiting?
> Thanks and regards!
>

Assuming you mean subprocess.Popen, the child is executed
asynchronously.  You can use the wait() method on the Popen object if
you want the parent to wait for the child to finish.

-- 
kushal


From piet at cs.uu.nl  Fri Jul 24 11:03:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:03:58 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<mailman.3662.1248445305.8015.python-list@python.org>
Message-ID: <m23a8mi0m9.fsf@cs.uu.nl>

>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:

>RJ> On Fri, 24 Jul 2009 14:55:45 +0100, Hrvoje Niksic <hniksic at xemacs.org>  wrote:
>>> Ben Finney <ben+python at benfinney.id.au> writes:
>>> 
>>>> Utpal Sarkar <doetoe at gmail.com> writes:
>>>> 
>>>>> Is there a way I can tell a variable that the object it is pointing
>>>>> too is not owned by it, in the sense that if it is the only reference
>>>>> to the object it can be garbage collected?
>>>> 
>>>> Python doesn't have ?pointers?, and doesn't really have ?variables?
>>>> either, at least not how many other languages use that term.
>>> 
>>> The OP didn't use the term "pointer", but the word "pointing", which
>>> makes sense in the context.  The term "variable" is used in the Python
>>> language reference and elsewhere, and is quite compatible with how other
>>> popular languages (Java, PHP, Lisp, ...) use it.

>RJ> Only superficially.  Treating Python variables the same as C variables
>RJ> (say) is one of the classic ways that newbies come unstuck when mutable
>RJ> objects appear on the scene.  While the OP appears to have the right idea,
>RJ> your "correction" here could be quite misleading.

If you read the OP, it is clear that he talked about a class variable,
which is a perfectly legal notion in Python, and is mentioned as such in
the language reference manual:
`Variables defined in the class definition are class variables'

And who was talking about C variables?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Fri Jul 24 11:06:23 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:06:23 +0200
Subject: how to get no value
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <m2vdliglxs.fsf@cs.uu.nl>

Well actually your subject is `how to get no value'. Your code does that
perfectly. :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From inky788 at gmail.com  Fri Jul 24 11:07:30 2009
From: inky788 at gmail.com (Inky 788)
Date: Fri, 24 Jul 2009 08:07:30 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
	<mailman.3570.1248335976.8015.python-list@python.org>
Message-ID: <f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>

On Jul 23, 3:42?am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Wednesday 22 July 2009 16:36:51 Inky 788 wrote:
>
> > On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
>
> > wrote:
> > > The good reason is the immutability, which lets you use
> > > a tuple as a dict key. ?
>
> > Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> > just not sophisticated enough, but I've never wanted to use a list/
> > tuple as a dict key. This sounds like obscure usage, and a bit
> > contrived as a reason for having *both* lists and tuples.
>
> Steven showed why you cannot have a mutable thing
> as a key in a dict.
>
> if you think it is contrived, then please consider how you would
> keep track of say the colour of a pixel on a screen at position
> (x,y) - this is about the simplest "natural" tuple format and
> example.

My guess is that this is probably the way most people do it:

~~~~
#!/usr/bin/env python

import sys
import random

if len( sys.argv ) != 3:
    print "Please pass exactly 2 ints. Exiting."
    sys.exit(1)

NUM_COLUMNS = int( sys.argv[1] )
NUM_ROWS    = int( sys.argv[2] )

print "Making array of %s columns by %s rows." % (NUM_COLUMNS,
NUM_ROWS)

def rand():
    return int( 255 * random.random())

def make_a_pixel():
    #       red     green   blue
    return [rand(), rand(), rand()]

def make_a_row(num_columns):
    temp_row = []
    for i in range(num_columns):
        temp_row.append( make_a_pixel() )
    return temp_row

def make_array_of_pixels(num_columns, num_rows):
    rows = []
    for i in range(num_rows):
        rows.append( make_a_row(num_columns) )
    return rows

def show_pixels(pixel_array):
    for row in pixel_array:
        for pixel in row:
            print pixel, '  ',
        print


rows_of_pixels = make_array_of_pixels(NUM_COLUMNS, NUM_ROWS)

show_pixels(rows_of_pixels)
~~~~


From piet at cs.uu.nl  Fri Jul 24 11:10:07 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:10:07 +0200
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
Message-ID: <m2r5w6glrk.fsf@cs.uu.nl>

>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:

>RJ> On Fri, 24 Jul 2009 14:57:02 +0100, Grant Edwards <invalid at invalid> wrote:
>>> On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>>>> 
>>>> Some aspects of the Python design are remarkably clever, while
>>>> others leave me perplexed. Here's an example of the latter:
>>>> Why does len() give an error when applied to an int or float?
>>>> len() should always return something; in particular, when
>>>> applied to a scalar, it should return a value of 1.
>>> 
>>> If len(7) returned a value of 1, then wouldn't one expect 7[0]
>>> to be valid?  It isn't, so you'd then have to redefine all
>>> types so that they are sequences that can be indexed.  Sounds
>>> like a big mess to me...
>>> 
>>> [Are there types for which len() returns a value that can't be
>>> indexed?]
>>> 

>RJ> Dictionaries.

>RJ> Which doesn't make your point less valid.  In fact I'd go so
>RJ> far as to argue that what len() gives you is the number of
>RJ> items in a container, so len(7) should return 0.

But len(7) could as well be defined as 3, 1, 32, or 64 (depending on the
implementation). Therefore it doesn't make much sense.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From ben+python at benfinney.id.au  Fri Jul 24 11:14:06 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 25 Jul 2009 01:14:06 +1000
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
Message-ID: <8763di5d1d.fsf@benfinney.id.au>

Hrvoje Niksic <hniksic at xemacs.org> writes:

> The term "variable" is used in the Python language reference and
> elsewhere

Yes. It should also be abundantly clear from the constant stream of
confused newbies on this point that its usage of that term is different
to what many expect from usage elsewhere.

> and is quite compatible with how other popular languages (Java, PHP,
> Lisp, ...) use it. Please stop complaining about valid terminology; it
> is not helpful.

I disagree with your assertions.

Rather than yet another round of this tedious debate, I merely point
interested readers to <URL:http://effbot.org/zone/python-objects.htm>
and ask them to draw their own conclusion on how compatible their
pre-existing ?variable? concept is with Python's object reference
model.

-- 
 \     ?Too many pieces of music finish too long after the end.? ?Igor |
  `\                                                       Stravinskey |
_o__)                                                                  |
Ben Finney


From piet at cs.uu.nl  Fri Jul 24 11:17:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:17:56 +0200
Subject: Popen
References: <mailman.3660.1248444211.8015.python-list@python.org>
Message-ID: <m2my6uglej.fsf@cs.uu.nl>

>>>>> Tim <timlee126 at yahoo.com> (T) wrote:

>T> Hi,
>T> I wonder if I use Popen, the parent process will wait for the child process to finish or continue without waiting?
>T> Thanks and regards!

Only if you use Popen.wait(),  Popen.communicate() or something similar
like os.waitpid(), subprocess.call()
      

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rylesny at gmail.com  Fri Jul 24 11:22:55 2009
From: rylesny at gmail.com (ryles)
Date: Fri, 24 Jul 2009 08:22:55 -0700 (PDT)
Subject: difference in printing to screen Mac / Windows
References: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com> 
	<mailman.3354.1247914997.8015.python-list@python.org>
Message-ID: <eeccc6b5-f4aa-49b9-93e6-803a6c77c8ab@d4g2000vbm.googlegroups.com>

On Jul 18, 7:03?am, Tim Chase <python.l... at tim.thechases.com> wrote:
> Lastly, you can force all standard-output in your program to be
> unbuffered without the "-u" parameter:

And if you're using -u a lot, the PYTHONUNBUFFERED environment
variable can also be set (but not empty), so that python adds the
option automatically.


From Scott.Daniels at Acm.Org  Fri Jul 24 11:54:32 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 24 Jul 2009 08:54:32 -0700
Subject: regex: multiple matching for one string
In-Reply-To: <e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
	<zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com>
	<e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com>
Message-ID: <o7Kdncbpm-78SvTXnZ2dnUVZ_vmdnZ2d@pdx.net>

rurpy at yahoo.com wrote:
> Nick Dumas wrote:
>> On 7/23/2009 9:23 AM, Mark Lawrence wrote:
>>> scriptlearner at gmail.com wrote:
>>>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>>>> will like to take out the values (valuea, valueb, and valuec).  How do
>>>> I do that in Python?  The group method will only return the matched
>>>> part.  Thanks.
>>>>
>>>> p = re.compile('#a=*;b=*;c=*;')
>>>> m = p.match(line)
>>>>         if m:
>>>>              print m.group(),
>>> IMHO a regex for this is overkill, a combination of string methods such
>>> as split and find should suffice.
> 
> You're saying that something like the following
> is better than the simple regex used by the OP?
> [untested]
> values = []
> parts = line.split(';')
> if len(parts) != 4: raise SomeError()
> for p, expected in zip (parts[-1], ('#a','b','c')):
>     name, x, value = p.partition ('=')
>     if name != expected or x != '=':
>         raise SomeError()
>     values.append (value)
> print values[0], values[1], values[2]
I call straw man: [tested]
     line = "#a=valuea;b=valueb;c=valuec;"
     d = dict(single.split('=', 1)
              for single in line.split(';') if single)
     d['#a'], d['b'], d['c']
If you want checking code, add:
     if len(d) != 3:
         raise ValueError('Too many keys: %s in %r)' % (
                              sorted(d), line))

> Blech, not in my book.  The regex checks the
> format of the string, extracts the values, and
> does so very clearly.  Further, it is easily
> adapted to other similar formats, or evolutionary
> changes in format.  It is also (once one is
> familiar with regexes -- a useful skill outside
> of Python too) easier to get right (at least in
> a simple case like this.)
The posted regex doesn't work; this might be homework, so
I'll not fix the two problems.  The fact that you did not
see the failure weakens your claim of "does so very clearly."

--Scott David Daniels
Scott.Daniels at Acm.Org


From pfeldman at verizon.net  Fri Jul 24 11:58:36 2009
From: pfeldman at verizon.net (Phillip M. Feldman)
Date: Fri, 24 Jul 2009 10:58:36 -0500 (CDT)
Subject: len() should always return something
Message-ID: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090724/6d9321db/attachment.html>

From Scott.Daniels at Acm.Org  Fri Jul 24 12:06:54 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 24 Jul 2009 09:06:54 -0700
Subject: Predefined Variables
In-Reply-To: <h49m7d$mch$1@foggy.unx.sas.com>
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
	<h49m7d$mch$1@foggy.unx.sas.com>
Message-ID: <iuKdnQ7T36jaR_TXnZ2dnUVZ_uSdnZ2d@pdx.net>

Stephen Cuppett (should have written in this order):
> "Fred Atkinson" <fatkinson at mishmash.com> wrote ...
>> Is there a pre-defined variable that returns the GET line
>>
>> (http://www.php.net/index.php?everythingafterthequestionmark) as a
>> single variable (rather than individual variables)?

 > os.environment('QUERY_STRING')

Maybe you mean:
     os.environ['USER']

--Scott David Daniels
Scott.Daniels at Acm.Org


From timlee126 at yahoo.com  Fri Jul 24 12:24:44 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 24 Jul 2009 09:24:44 -0700 (PDT)
Subject: Popen
Message-ID: <987525.41038.qm@web63102.mail.re1.yahoo.com>


Thanks! 
Yes I mean subprocess.Popen.

I was wondering the meaning of "asynchronously"
Here is some code I am reading recently:
"
result = Popen(cmdline,shell=True,stdout=PIPE).stdout 
for line in result.readlines():
    if find(line,"Cross") != -1:
        return float(split(line)[-1][0:-1]) 
"
The computation in the program "cmdline" takes a long time, at the end of which the results will be output to stdout.

"asynchronous" seems to mean Popen returns to the parent process immediately and the parent and child processes continue to be executed.
However, if Popen returns immediately to the parent process, then there will be nothing in "result", not to mention extracting information from the output. Thus it seems to me the parent process has to wait till the child process finish.

So how to understand the meaning of "asynchronous"?

Thanks and regards!


--- On Fri, 7/24/09, Kushal Kumaran <kushal.kumaran+python at gmail.com> wrote:

> From: Kushal Kumaran <kushal.kumaran+python at gmail.com>
> Subject: Re: Popen
> To: "Tim" <timlee126 at yahoo.com>
> Cc: python-list at python.org
> Date: Friday, July 24, 2009, 10:58 AM
> On Fri, Jul 24, 2009 at 7:33 PM,
> Tim<timlee126 at yahoo.com>
> wrote:
> >
> > Hi,
> > I wonder if I use Popen, the parent process will wait
> for the child process to finish or continue without
> waiting?
> > Thanks and regards!
> >
> 
> Assuming you mean subprocess.Popen, the child is executed
> asynchronously.? You can use the wait() method on the
> Popen object if
> you want the parent to wait for the child to finish.
> 
> -- 
> kushal
> 


      


From deets at nospam.web.de  Fri Jul 24 12:35:56 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 18:35:56 +0200
Subject: Popen
In-Reply-To: <mailman.3664.1248452692.8015.python-list@python.org>
References: <mailman.3664.1248452692.8015.python-list@python.org>
Message-ID: <7cu67cF29g680U1@mid.uni-berlin.de>

Tim schrieb:
> Thanks! 
> Yes I mean subprocess.Popen.
> 
> I was wondering the meaning of "asynchronously"
> Here is some code I am reading recently:
> "
> result = Popen(cmdline,shell=True,stdout=PIPE).stdout 
> for line in result.readlines():
>     if find(line,"Cross") != -1:
>         return float(split(line)[-1][0:-1]) 
> "
> The computation in the program "cmdline" takes a long time, at the end of which the results will be output to stdout.
> 
> "asynchronous" seems to mean Popen returns to the parent process immediately and the parent and child processes continue to be executed.
> However, if Popen returns immediately to the parent process, then there will be nothing in "result", not to mention extracting information from the output. Thus it seems to me the parent process has to wait till the child process finish.
> 
> So how to understand the meaning of "asynchronous"?

"Asynchronous" means asynchronous - the parent is *not* waiting.

Which is the reason that there is (amongst other things) the 
"wait"-method you can call to wait for the child to be terminated.

Diez


From bieffe62 at gmail.com  Fri Jul 24 12:40:22 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Fri, 24 Jul 2009 09:40:22 -0700 (PDT)
Subject: Popen
References: <mailman.3664.1248452692.8015.python-list@python.org>
Message-ID: <7df4ca4e-476a-4b3c-99d4-e710c75ab80b@o15g2000yqm.googlegroups.com>

On Jul 24, 6:24?pm, Tim <timlee... at yahoo.com> wrote:
> Thanks!
> Yes I mean subprocess.Popen.
>
> I was wondering the meaning of "asynchronously"
> Here is some code I am reading recently:
> "
> result = Popen(cmdline,shell=True,stdout=PIPE).stdout
> for line in result.readlines():
> ? ? if find(line,"Cross") != -1:
> ? ? ? ? return float(split(line)[-1][0:-1])
> "
> The computation in the program "cmdline" takes a long time, at the end of which the results will be output to stdout.
>
> "asynchronous" seems to mean Popen returns to the parent process immediately and the parent and child processes continue to be executed.

This is correct

> However, if Popen returns immediately to the parent process, then there will be nothing in "result", not to mention extracting information from the output. Thus it seems to me the parent process has to wait till the child process finish.
>

Calling result.readlines() the parent process attempts to read from
stdout until end of file. For a pipe, end of file means that
the other end is closing its connection, which - unless the child
process closes stdout  explicitely - means that the child
process is terminated.
So the end effect is the almost like  using 'communicate' on the
result of Popen, except that communicates returns both standard output
and standard error contents at the same time.



> So how to understand the meaning of "asynchronous"?
>
> Thanks and regards!

HTH

Ciao
-----
FB


From mathieu.malaterre at gmail.com  Fri Jul 24 12:48:22 2009
From: mathieu.malaterre at gmail.com (mathieu)
Date: Fri, 24 Jul 2009 09:48:22 -0700 (PDT)
Subject: SONAME for python modules is bad? (aka multiple module version)
Message-ID: <2a2a36ca-72a0-470f-907c-2be43104617a@h18g2000yqj.googlegroups.com>

As far as I know there has not been any consensus on how to install
multiple version of a same module in python ? What are the recommended
mechanism ?

I could not find any documentation on the subject. Does anyone sees
any issue with using standard SONAME mechanism when installing a
python module ?

Thanks,

ref:
http://mail.python.org/pipermail/pythonmac-sig/2009-January/020936.html


From timlee126 at yahoo.com  Fri Jul 24 12:52:01 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 24 Jul 2009 09:52:01 -0700 (PDT)
Subject: Popen
Message-ID: <414673.50429.qm@web63108.mail.re1.yahoo.com>


Thanks! If that is the case, i.e. the parent doesn't wait, is the code in my last post wrong? "result" could be nothing.

--- On Fri, 7/24/09, Diez B. Roggisch <deets at nospam.web.de> wrote:

> From: Diez B. Roggisch <deets at nospam.web.de>
> Subject: Re: Popen
> To: python-list at python.org
> Date: Friday, July 24, 2009, 12:35 PM
> Tim schrieb:
> > Thanks! Yes I mean subprocess.Popen.
> > 
> > I was wondering the meaning of "asynchronously"
> > Here is some code I am reading recently:
> > "
> > result = Popen(cmdline,shell=True,stdout=PIPE).stdout
> for line in result.readlines():
> >? ???if find(line,"Cross") != -1:
> >? ? ? ???return
> float(split(line)[-1][0:-1]) "
> > The computation in the program "cmdline" takes a long
> time, at the end of which the results will be output to
> stdout.
> > 
> > "asynchronous" seems to mean Popen returns to the
> parent process immediately and the parent and child
> processes continue to be executed.
> > However, if Popen returns immediately to the parent
> process, then there will be nothing in "result", not to
> mention extracting information from the output. Thus it
> seems to me the parent process has to wait till the child
> process finish.
> > 
> > So how to understand the meaning of "asynchronous"?
> 
> "Asynchronous" means asynchronous - the parent is *not*
> waiting.
> 
> Which is the reason that there is (amongst other things)
> the "wait"-method you can call to wait for the child to be
> terminated.
> 
> Diez
> -- http://mail.python.org/mailman/listinfo/python-list
> 


      


From marcusw at cox.net  Fri Jul 24 12:57:57 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 24 Jul 2009 12:57:57 -0400
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <mailman.3473.1248192801.8015.python-list@python.org>
References: <mailman.3406.1248034495.8015.python-list@python.org>	<h40adj$bv6$1@adenine.netfront.net>	<mailman.3419.1248082444.8015.python-list@python.org>	<h428fp$8ja$2@adenine.netfront.net>
	<mailman.3473.1248192801.8015.python-list@python.org>
Message-ID: <h4cp6l$2khu$1@adenine.netfront.net>

On 7/21/2009 12:13 PM, Stef Mientki wrote:
> hi Marcus,
>>>> That sounds like a very specialized type of thing, 
>>> Well from an application point of view,
>>> with the current netbooks,
>>> this looks like a perfect tool for any conversation or meeting.
>>>> which only the few people with experience with wxPython, PyAudio, 
>>>> and Scintilla could help you with...
>>>>
>>> I was afraid of that too, so I dropped the question in several places,
>>> and the writer of Scintilla himself came with the perfect answer.
>>>
>>> cheers,Stef
>>>> But you might try having a dictionary with notes and associated 
>>>> times, or just give each note a four-digit ID number at the 
>>>> beginning of it when it's entered and use that in the dictionary (to 
>>>> keep keys shorter). Or you could just do a little hack and increase 
>>>> the number of bookmarks allowed (seeing as source is available) :p
>>>>
>>>> Marcus
>>>
>> Glad you got a good answer from somebody. Sounds like an interesting 
>> project. About when would this be headed for a release? Could you post 
>> a link to a googlecode or sourceforge project or something so I can 
>> follow and/or help with development?
>>
> For the moment it's just an idea, so no line of code yet.
> I first like to tackle all the problems,
> at least to the level I think I can handle them.
> So first solve the next problem,
> before I start coding:
> automatic synchronization (file uploading and deleting) between EEE-pc 
> and desktop PC over bluetooth.
> And another problem, as my customers are physicians,
> both the text and audio need to be stored encrypted.
> 
> cheers,
> Stef
>> Marcus
> 
I would recommend pybluez and 
http://www.google.com/search?q=python+aes+encryption

Marcus


From kyrie at uh.cu  Fri Jul 24 13:00:38 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Fri, 24 Jul 2009 13:00:38 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<mailman.3570.1248335976.8015.python-list@python.org>
	<f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
Message-ID: <200907241300.38738.kyrie@uh.cu>

On Friday 24 July 2009 11:07:30 am Inky 788 wrote:
> On Jul 23, 3:42?am, Hendrik van Rooyen <hend... at microcorp.co.za>
> > if you think it is contrived, then please consider how you would
> > keep track of say the colour of a pixel on a screen at position
> > (x,y) - this is about the simplest "natural" tuple format and
> > example.
>
> My guess is that this is probably the way most people do it:
[...]
> def make_array_of_pixels(num_columns, num_rows):
[...]

If you need to hold /every/ pixel on the screen, it makes sense to have a 
bidimentional array of points and colors. But if you need to hold a 
non-rectangular subset, or even a subset that doesn't need to be rectangular, 
you can either use dicts, or ... do what you did. Most people will use the 
less contrived version of:

screen = {}
screen[1,2] = (rand(), rand(), rand())

(btw, in your make_a_pixel function, unless you want to make the pixels 
updatable in place, you should also be using a tuple).

Sparse datasets are extremely common, and dicts are a good way to 
[temporarily] store them.

As someone mentioned before, dictionaries are essential to python. Don't go 
out of your way to avoid them, unless you have a /reason/ to do it.

Btw,

def get_color(point):
    return screen[point]

is way more readable (and less obscure) than

def get_color(point):
    return rows_of_pixels[point[0]][point[1]]

Regards,
-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From clp2 at rebertia.com  Fri Jul 24 13:02:30 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 10:02:30 -0700
Subject: effbot.org broken (WAS: Problems in commands.getoutput(cmd) with 
	sox)
In-Reply-To: <m2ljmeifo4.fsf@cs.uu.nl>
References: <mailman.3620.1248378772.8015.python-list@python.org>
	<m2ljmeifo4.fsf@cs.uu.nl>
Message-ID: <50697b2c0907241002o1cd9f262h853c2abe2ce534f6@mail.gmail.com>

On Fri, Jul 24, 2009 at 2:38 AM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:
>
>>CR> On Thu, Jul 23, 2009 at 12:42 PM, Chris Rebert<clp2 at rebertia.com> wrote:
>>>> You can use tabnanny to help diagnose the problem:
>>>> http://74.125.155.132/search?q=cache:QtxvZm3QDLsJ:effbot.org/librarybook/tabnanny.htm+tabnanny&cd=3&hl=en&ct=clnk&gl=us&client=firefox-a
>
>>CR> Anyone know what's the deal with effbot.org? It seems to be broken at
>>CR> present, forcing me to use Google's cached version.
>>CR> It's a real shame since it has lots of handy Python info.
>
> Just try again.

Yup, whatever the problem was, seems to be fixed now. Interesting.

- Chris


From roastie57 at gmail.com  Fri Jul 24 13:14:31 2009
From: roastie57 at gmail.com (Uncle Roastie)
Date: Fri, 24 Jul 2009 10:14:31 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <0505d29f-edeb-40a4-b513-6117ecf4de33@m18g2000vbi.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> My colleagues and I have been working with python for around 6 months
> now, and while we love a lot of what python has done for us and what
> it enables us to do some of the decisions behind such certain
> data-types and their related methods baffle us slightly (when compared
> to the decisions made in other, similarly powerful languages).
>
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
>
> Consider the following:
>
> >>> x = [2,1,3]
> >>> x.sort()
> >>> print x
>
> [1, 2, 3]
>
> Now, if the sort operations were unable to affect the original
> structure of the list (as in JavaScript) you'd effectively have a
> tuple which you could add/remove from, and the example above would
> look more like:
>
> >>> x = [2,1,3]
> >>> print x.sort()
> [1, 2, 3]
> >>> print x
>
> [2,1,3]
>
> This make a lot more sense to us, and follows the convention from
> other languages. It would also mean chaining methods to manipulate
> lists would be easier:
>
> >>> x = [2,1,3]
> >>> print x.sort()[0]
> 3
> >>> print x
>
> [2,1,3]
>
> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.
>
> We're not looking to start any arguments or religious wars and we're
> not asking that python be changed into something its not. We'd simply
> like to understand the decision behind the lists and tuple structures.
> We feel that in not "getting" the difference between the two types we
> may be missing out on using these data structures to their full
> potential.

A tuple can be used like a struct in C - the number of fields is meant
to
be fixed and should not be dynamically changed.


From gert.cuykens at gmail.com  Fri Jul 24 13:22:36 2009
From: gert.cuykens at gmail.com (gert)
Date: Fri, 24 Jul 2009 10:22:36 -0700 (PDT)
Subject: cgi.fieldstorage()
Message-ID: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>

this is a non standard way to store multi part post data on disk

def application(environ, response):
    with open('/usr/httpd/var/wsgiTemp','w') as f:
        while True:
            chunk = environ['wsgi.input'].read(8192).decode('latin1')
            if not chunk: break
            f.write(chunk)
    response('200 OK',[])
    return ['complete']

my question is how do i handle the file, so i can shuffle it into a db
using small chunks of memorie ?


From deets at nospam.web.de  Fri Jul 24 13:27:16 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 19:27:16 +0200
Subject: SONAME for python modules is bad? (aka multiple module version)
In-Reply-To: <2a2a36ca-72a0-470f-907c-2be43104617a@h18g2000yqj.googlegroups.com>
References: <2a2a36ca-72a0-470f-907c-2be43104617a@h18g2000yqj.googlegroups.com>
Message-ID: <7cu97kF29dnlbU1@mid.uni-berlin.de>

mathieu schrieb:
> As far as I know there has not been any consensus on how to install
> multiple version of a same module in python ? What are the recommended
> mechanism ?


I use virtualenvs for everything. Especially on unixish OSes this 
usually works without problems. On windows, things are a bit different, 
as sometimes you only get binary installers that insist on installing 
into the base-installation.

> I could not find any documentation on the subject. Does anyone sees
> any issue with using standard SONAME mechanism when installing a
> python module ?


I don't understand that. You mean the .so.X.Y.Z-thingy under *ix? That 
would essentially be the pkg_resources.require-road, yes. But as it's 
not widely adopted, it will cause you troubles because some packages 
won't declare their dependencies properly.

Diez


From clp2 at rebertia.com  Fri Jul 24 13:28:10 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 10:28:10 -0700
Subject: Popen
In-Reply-To: <414673.50429.qm@web63108.mail.re1.yahoo.com>
References: <414673.50429.qm@web63108.mail.re1.yahoo.com>
Message-ID: <50697b2c0907241028s4f3ff1e6ma4f78ae2b61b2341@mail.gmail.com>

> --- On Fri, 7/24/09, Diez B. Roggisch <deets at nospam.web.de> wrote:
>
>> From: Diez B. Roggisch <deets at nospam.web.de>
>> Subject: Re: Popen
>> To: python-list at python.org
>> Date: Friday, July 24, 2009, 12:35 PM
>> Tim schrieb:
>> > Thanks! Yes I mean subprocess.Popen.
>> >
>> > I was wondering the meaning of "asynchronously"
>> > Here is some code I am reading recently:
>> > "
>> > result = Popen(cmdline,shell=True,stdout=PIPE).stdout
>> for line in result.readlines():
>> >? ???if find(line,"Cross") != -1:
>> >? ? ? ???return
>> float(split(line)[-1][0:-1]) "
>> > The computation in the program "cmdline" takes a long
>> time, at the end of which the results will be output to
>> stdout.
>> >
>> > "asynchronous" seems to mean Popen returns to the
>> parent process immediately and the parent and child
>> processes continue to be executed.
>> > However, if Popen returns immediately to the parent
>> process, then there will be nothing in "result", not to
>> mention extracting information from the output. Thus it
>> seems to me the parent process has to wait till the child
>> process finish.
>> >
>> > So how to understand the meaning of "asynchronous"?
>>
>> "Asynchronous" means asynchronous - the parent is *not*
>> waiting.
>>
>> Which is the reason that there is (amongst other things)
>> the "wait"-method you can call to wait for the child to be
>> terminated.

On Fri, Jul 24, 2009 at 9:52 AM, Tim<timlee126 at yahoo.com> wrote:
>
> Thanks! If that is the case, i.e. the parent doesn't wait, is the code in my last post wrong? "result" could be nothing.

No, it will be a subprocess.Popen object representing the spawned
process. Both the child process and the parent Python process will
then be running simultaneously.This allows the Python program to
interact with the subprocess via the Popen object while the subprocess
is executing in parallel with Python.
The asynchronicity means that the call to the Popen constructor does
not wait for the spawned subprocess to terminate before returning the
new Popen object to the parent Python program.

Cheers,
Chris
-- 
http://blog.rebertia.com


From deets at nospam.web.de  Fri Jul 24 13:32:31 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 19:32:31 +0200
Subject: cgi.fieldstorage()
In-Reply-To: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
Message-ID: <7cu9hhF29gt65U1@mid.uni-berlin.de>

gert schrieb:
> this is a non standard way to store multi part post data on disk
> 
> def application(environ, response):
>     with open('/usr/httpd/var/wsgiTemp','w') as f:
>         while True:
>             chunk = environ['wsgi.input'].read(8192).decode('latin1')
>             if not chunk: break
>             f.write(chunk)
>     response('200 OK',[])
>     return ['complete']
> 
> my question is how do i handle the file, so i can shuffle it into a db
> using small chunks of memorie ?

I don't think that's possible with the current DB-API. There is no 
stream-based BLOB-interface (as e.g. JDBC offers).

So the answer certainly depends on your used RDBMS. For oracle, you 
would be lucky:

http://cx-oracle.sourceforge.net/html/lob.html


Other adapters I don't know about.

Diez


From clp2 at rebertia.com  Fri Jul 24 13:41:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 10:41:13 -0700
Subject: trouble with wrapping a c program
In-Reply-To: <20090724123458.TOWM14607.viefep17-int.chello.at@edge02.upc.biz>
References: <20090724123458.TOWM14607.viefep17-int.chello.at@edge02.upc.biz>
Message-ID: <50697b2c0907241041l10d13f09pa01abb505461e737@mail.gmail.com>

On Fri, Jul 24, 2009 at 5:34 AM, Sanne Korzec<sanne at kortec.nl> wrote:
> Hi Mailing,
>
> I am using a c program, which first initializes for some seconds and then
> waits for user input (keyboard) to type something. When enter is pressed the
> c program continues.
<snip>
> Using the keyboard and then enter in the c program prompt works, but I wish
> to do this from the python script by sending the string from the python
> script.
>
> I am able to print the string from python with a print command or with a
> stdout.write command. But this simply prints it to the prompt, the c program
> does nothing with this printed string.
>
> Is there a way to pipe, stream, or send this string to the running c
> program?
<snip>
> Here is a small fragment of my code:
>
> #initialization
>
> cmd = [a list of my program and arguments]
>
> subprocess.Popen(cmd)?? #starts the c program

import subprocess
cmd = [a list of my program and arguments]
process = subprocess.Popen(cmd, stdin=subprocess.PIPE)   #starts the c program
line = raw_input("Please enter a line of input for the C program:")
process.stdin.write(line)
process.stdin.write("\n")

You might want to study the docs for the subprocess module:
http://docs.python.org/library/subprocess.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From kyrie at uh.cu  Fri Jul 24 13:46:10 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Fri, 24 Jul 2009 13:46:10 -0400
Subject: len() should always return something
In-Reply-To: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
Message-ID: <200907241346.10966.kyrie@uh.cu>

On Friday 24 July 2009 11:58:36 am Phillip M. Feldman wrote:
> I've been converting Matlab codes to Python.? In Matlab, a scalar is just a
> one-by-one matrix and has a length of 1.? This convention seems no less
> arbitrary to me than Python's convention that the concept of length is not
> applicable to ints and floats.

Are you sure it isn't? (as opposed to being tainted by matlab?).

Almost everywhere, a scalar and a tuple are different things. How many 
elements are "inside" the number 7? If you assume that 7 is a matrix, why 
should it be a two-dimensional matrix? Why not a vector, or a three 
dimensional matrix instead? (I don't use matlab, but in octave, size(7) 
returns [1,1], not [1] or [1,1,1,1]).

That seems even more arbitrary to me. Of course, in a language like Matlab, 
that assumes that everything is a matrix, it makes sense for scalars to be 
mapped to a useful matrices. But that assumption is not natural.

Even pure math makes a difference between scalars and vectors. Matrix x Matrix 
multiplication is not always defined (even when the second matrix contains 
exactly one element), while Matrix x Scalar always is. (Octave, btw, will 
demote a two-dimensional 1x1 matrix to a scalar for Matrix multiplication, 
which may hide errors)

If you are converting from matlab, I'd say you have biggest things to worry 
about. As you said, you can just replace the len function (even safer may be 
to do [1]). Assignment, for instance, is /very/ different.

> If there is only a single measurement, it is reasonable to allow the calling 
> program to pass a scalar without wrapping it up into a list or array.

I try to avoid those automatic conversions, on the long run, I believe that 
most of them make the code more confusing for the caller. If you feel that 
you must allow that, my suggestion would be to create a method that will 
ensure that what you receive is a list (or whatever) and coerce its argument 
if not, and call that one at the beginning of your methods.

Regards,

[1] this will define len for any object, not only int and floats.
===
def size(x):
    try:
        return len(x)
    except TypeError:
        return 1,1
===

-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From rhodri at wildebst.demon.co.uk  Fri Jul 24 13:52:41 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 18:52:41 +0100
Subject: len() should always return something
In-Reply-To: <m2r5w6glrk.fsf@cs.uu.nl>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<m2r5w6glrk.fsf@cs.uu.nl>
Message-ID: <op.uxk2l3tta8ncjz@gnudebst>

On Fri, 24 Jul 2009 16:10:07 +0100, Piet van Oostrum <piet at cs.uu.nl> wrote:

>>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:
>
>> RJ> On Fri, 24 Jul 2009 14:57:02 +0100, Grant Edwards <invalid at invalid>  
>> wrote:
>>>> On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>>>>>
>>>>> Some aspects of the Python design are remarkably clever, while
>>>>> others leave me perplexed. Here's an example of the latter:
>>>>> Why does len() give an error when applied to an int or float?
>>>>> len() should always return something; in particular, when
>>>>> applied to a scalar, it should return a value of 1.
>>>>
>>>> If len(7) returned a value of 1, then wouldn't one expect 7[0]
>>>> to be valid?  It isn't, so you'd then have to redefine all
>>>> types so that they are sequences that can be indexed.  Sounds
>>>> like a big mess to me...
>>>>
>>>> [Are there types for which len() returns a value that can't be
>>>> indexed?]
>>>>
>
>> RJ> Dictionaries.
>
>> RJ> Which doesn't make your point less valid.  In fact I'd go so
>> RJ> far as to argue that what len() gives you is the number of
>> RJ> items in a container, so len(7) should return 0.
>
> But len(7) could as well be defined as 3, 1, 32, or 64 (depending on the
> implementation). Therefore it doesn't make much sense.

Quite.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From andre.roberge at gmail.com  Fri Jul 24 13:54:21 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Fri, 24 Jul 2009 10:54:21 -0700 (PDT)
Subject: ElementTree's Element substitution in Python 3
Message-ID: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>

I have a function to replace the content of an ElementTree Element by
that of another one which works using Python 2 but not with Python 3.
I get an assertion error.  The function is as follows:

def replace_element(elem, replacement):
    '''replace the content of an ElementTree Element by that of
another
       one.
    '''
    elem.clear()
    elem.text = replacement.text
    elem.tail = replacement.tail
    elem.tag = replacement.tag
    elem.attrib = replacement.attrib
    elem[:] = replacement[:]

The last line is problematic.  For example, if I do the following
program with Python2.5
###
from xml.etree import ElementTree as et

a = et.Element('a')
b = et.SubElement(a, 'b')
c = et.Element('c')

a[:] = c[:]
###
nothing of note happens - however, doing the same with Python 3.1, I
get the following traceback:

Traceback (most recent call last):
  File "test.py", line 7, in <module>
    a[:] = c[:]
  File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
210, in __setitem__
    assert iselement(element)
AssertionError

======
I would gladly welcome any suggestion for writing a replace_element()
function that works with Python 3.1

Andr?


From ronn.ross at gmail.com  Fri Jul 24 13:56:29 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Fri, 24 Jul 2009 12:56:29 -0500
Subject: trouble with minidom
In-Reply-To: <op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
	<op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <9c8c445f0907241056x11ec5316s2ea6310872cd342@mail.gmail.com>

On Tue, Jul 21, 2009 at 7:32 PM, Gabriel Genellina
<gagsl-py2 at yahoo.com.ar>wrote:

> En Tue, 21 Jul 2009 21:08:57 -0300, Ronn Ross <ronn.ross at gmail.com>
> escribi?:
>
>
>  Hello I'm trying to read an xml file using minidome. The xml looks like:
>> <rootNode>
>>   <project>
>>      <name>myProj</name>
>>      <path>/here/</path>
>>   </project>
>> </rootNode>
>>
>> My code looks like so:
>> from xml.dom.minidom import parse
>>
>> dom = parse("myfile.xml")
>>
>> for node in dom.getElementsByTagName("project'):
>>   print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,
>> node.childNodes[1])
>>
>> Unfortunately, it returns 'nodeValue as none. I'm trying to read the value
>> out of the node fir example name: myProj. I haven't found much help in the
>> documentation. Can someone point me in the right direction?
>>
>
> Unless you have a specific reason to use the DOM interface (like having a
> masochistic mind), working with ElementTree usually is a lot easier:
>
> py> import xml.etree.ElementTree as ET
> py> xml = """<rootNode>
> ... <project>
> ...        <name>myProj</name>
> ...        <path>/here/</path>
> ... </project>
> ... </rootNode>"""
> py> doc = ET.fromstring(xml)
> py> for project in doc.findall('project'):
> ...   for child in project.getchildren():
> ...     print child.tag, child.text
> ...
> name myProj
> path /here/
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


I have used the loop below and it works great, but I need get both child
elements or 'project' per iteration. I want to build a dictionary that
resemble this:
my_dict = {'myProj':'/here/', 'anothername':'anotherpath'}

I couldn't find how to do with in the element tree docs. Can you point me in
the right direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090724/043fd697/attachment.html>

From clp2 at rebertia.com  Fri Jul 24 14:03:59 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 11:03:59 -0700
Subject: len() should always return something
In-Reply-To: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
Message-ID: <50697b2c0907241103v5ad12d48re1857532c58903e8@mail.gmail.com>

> Jul 24, 2009 07:02:29 AM, clp2 at rebertia.com wrote:
>
> On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
> Feldman<pfeldman at verizon.net> wrote:
>>
>> Some aspects of the Python design are remarkably clever, while others
>> leave
>> me perplexed. Here's an example of the latter: Why does len() give an
>> error
>> when applied to an int or float? len() should always return something; in
>> particular, when applied to a scalar, it should return a value of 1. Of
>> course, I can define my own function like this:
>>
>> def mylen(x):
>> ? if isinstance(x,int) or isinstance(x,float): return 1
>> ? return len(x)
>>
>> But, this shouldn't be necessary.
>
> The problem is that redefining len()/length/size that way would
> violate several principles of Python's design (The "Zen" of Python -
> http://www.python.org/dev/peps/pep-0020/).
>
> Specifically:
> - Explicit is better than implicit.
> - Special cases aren't special enough to break the rules.
> - Errors should never pass silently.
> - In the face of ambiguity, refuse the temptation to guess.
>
> If you'd explain the situation that prompts you to find this
> redefinition necessary, I'm sure someone can suggest a better
> approach.

On Fri, Jul 24, 2009 at 8:58 AM, Phillip M. Feldman<pfeldman at verizon.net> wrote:
> I've read the "Zen of Python", but most of these aphorisms are vague and
> could be understood differently by different readers.  In particular, I
> don't understand the statement that "explicit is better than implicit".
> Some examples of this would be helpful.
>
> I've been converting Matlab codes to Python.  In Matlab, a scalar is just a
> one-by-one matrix and has a length of 1.  This convention seems no less
> arbitrary to me than Python's convention that the concept of length is not
> applicable to ints and floats.  My workaround was to write the following
> function:
>
> def is_scalar(x):
>    """Return True if x is an instance of int, float, or complex.
>    Otherwise, return False.  Note: If x is a length-1 list or array
>    containing an int, float, or complex value, False is returned."""
>    if isinstance(x,int) or isinstance(x,float) or isinstance(x,complex):
>       return True
>    return False
>
> The application is the following: In various types of scientific
> applications, one operates on a list of measurements.  If there is only a
> single measurement, it is reasonable to allow the calling program to pass a
> scalar without wrapping it up into a list or array.

You could use Python's extended call syntax when defining your function:

def average(*args):
    return sum(args) / len(args)

average(7) #==> 7
average(2,3,4,5,6) #==> 4
average(*[2,3,4,5,6]) #==> 4
average([2,3,4,5,6]) #==> error

Cheers,
Chris
-- 
http://blog.rebertia.com


From rhodri at wildebst.demon.co.uk  Fri Jul 24 14:05:58 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 19:05:58 +0100
Subject: non-owning references?
In-Reply-To: <m23a8mi0m9.fsf@cs.uu.nl>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
	<mailman.3662.1248445305.8015.python-list@python.org>
	<m23a8mi0m9.fsf@cs.uu.nl>
Message-ID: <op.uxk278dca8ncjz@gnudebst>

On Fri, 24 Jul 2009 16:03:58 +0100, Piet van Oostrum <piet at cs.uu.nl> wrote:

>>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:
>
>> RJ> On Fri, 24 Jul 2009 14:55:45 +0100, Hrvoje Niksic  
>> <hniksic at xemacs.org>  wrote:
>>>> Ben Finney <ben+python at benfinney.id.au> writes:
>>>>
>>>>> Utpal Sarkar <doetoe at gmail.com> writes:
>>>>>
>>>>>> Is there a way I can tell a variable that the object it is pointing
>>>>>> too is not owned by it, in the sense that if it is the only  
>>>>>> reference
>>>>>> to the object it can be garbage collected?
>>>>>
>>>>> Python doesn't have ?pointers?, and doesn't really have ?variables?
>>>>> either, at least not how many other languages use that term.
>>>>
>>>> The OP didn't use the term "pointer", but the word "pointing", which
>>>> makes sense in the context.  The term "variable" is used in the Python
>>>> language reference and elsewhere, and is quite compatible with how  
>>>> other
>>>> popular languages (Java, PHP, Lisp, ...) use it.
>
>> RJ> Only superficially.  Treating Python variables the same as C  
>> variables
>> RJ> (say) is one of the classic ways that newbies come unstuck when  
>> mutable
>> RJ> objects appear on the scene.  While the OP appears to have the  
>> right idea,
>> RJ> your "correction" here could be quite misleading.
>
> If you read the OP, it is clear that he talked about a class variable,
> which is a perfectly legal notion in Python, and is mentioned as such in
> the language reference manual:
> `Variables defined in the class definition are class variables'

Yes.  I didn't think I needed to say that explicitly.

> And who was talking about C variables?

Hrvoje, implicitly.  'The term "variable" is used in the Python
language reference and elsewhere, and is quite compatible with how
other popular languages (Java, PHP, Lisp, ...) use it.'  I listed
C as another example of a popular language because I am very familiar
with how C's variables work; I don't know Java, I've never programmed
PHP in anger and it's twenty years since I last touched Lisp.

The point was, and remains, that this newsgroup gets regular traffic
 from people who expect Python's variables to act like C's variables,
demonstrating that describing them as "quite compatible" is somewhat
misleading.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Fri Jul 24 14:06:32 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Fri, 24 Jul 2009 14:06:32 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
Message-ID: <h4ctjv$bhj$1@news.eternal-september.org>

On 2009-07-23 23:51:02 -0400, Carl Banks <pavlovevidence at gmail.com> said:

> On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
>> fft1976 wrote:
>>> How do you explain that something as inferior as Python beat Lisp in
>>> the market place despite starting 40 years later.
>> 
>> Probably due to similar reasons that lead php to become remotely relevant
> .
> 
> Well, the only reason PHP became relevant because it was an


> easy

^^^^^^^^
^^^^^^^^ (emphasis added)

> to
> deploy solution in a single application domain, the web, that happened
> to explode.


i.e., Python "beat" lisp because it is ~70% of lisp in a form that is 
much more palatable to the average programmer, just as php became 
popular because it is powerful enough to do websites and, most 
importantly, apprehensible to mediocre programmers and even some 
non-programmers.

-- 
Raffael Cavallaro



From gert.cuykens at gmail.com  Fri Jul 24 14:10:17 2009
From: gert.cuykens at gmail.com (gert)
Date: Fri, 24 Jul 2009 11:10:17 -0700 (PDT)
Subject: cgi.fieldstorage()
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
Message-ID: <f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>

On Jul 24, 7:32?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> gert schrieb:
>
> > this is a non standard way to store multi part post data on disk
>
> > def application(environ, response):
> > ? ? with open('/usr/httpd/var/wsgiTemp','w') as f:
> > ? ? ? ? while True:
> > ? ? ? ? ? ? chunk = environ['wsgi.input'].read(8192).decode('latin1')
> > ? ? ? ? ? ? if not chunk: break
> > ? ? ? ? ? ? f.write(chunk)
> > ? ? response('200 OK',[])
> > ? ? return ['complete']
>
> > my question is how do i handle the file, so i can shuffle it into a db
> > using small chunks of memorie ?
>
> I don't think that's possible with the current DB-API. There is no
> stream-based BLOB-interface (as e.g. JDBC offers).
>
> So the answer certainly depends on your used RDBMS. For oracle, you
> would be lucky:
>
> http://cx-oracle.sourceforge.net/html/lob.html
>
> Other adapters I don't know about.

sqlite :) ok let say for now it would be impossible on a db level, but
before i reach the impossible, i still need to parse the file to
prepare the chunks. How do i do that ? How do i get the chunks without
loading the hole file into memorie ?

    b = environ['CONTENT_TYPE'].split('boundary=')[1]
    data = search(b+r'.*?Content-Type: application/octet-stream\r\n\r
\n
(.*?)\r\n--'+b,t,DOTALL).group(1)
    data = data.encode('latin1')


From jakecjacobson at gmail.com  Fri Jul 24 14:24:58 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Fri, 24 Jul 2009 11:24:58 -0700 (PDT)
Subject: exceptions.TypeError an integer is required
Message-ID: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>

I am trying to do a post to a REST API over HTTPS and requires the
script to pass a cert to the server.  I am getting
"exceptions.TypeError an integer is required" error and can't find the
reason.  I commenting out the lines of code, it is happening on the
connection.request() line.  Here is the problem code.  Would love some
help if possible.

	head = {"Content-Type" : "application/x-www-form-urlencoded",
"Accept" : "text/plain"}
	parameters = urlencode({"collection" : collection, "entryxml" : open
(file,'r').read()})
	try:
		connection = httplib.HTTPSConnection(host, port, key_file,
cert_file)
		connection.request('POST', path, parameters, head)
		response = connection.getresponse()
		print response.status, response.reason
	except:
		print sys.exc_type, sys.exc_value

	connection.close()


From piet at cs.uu.nl  Fri Jul 24 14:39:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 20:39:46 +0200
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
	<h49m7d$mch$1@foggy.unx.sas.com>
	<iuKdnQ7T36jaR_TXnZ2dnUVZ_uSdnZ2d@pdx.net>
Message-ID: <m2hbx2gc25.fsf@cs.uu.nl>

>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) wrote:

>SDD> Stephen Cuppett (should have written in this order):
>>> "Fred Atkinson" <fatkinson at mishmash.com> wrote ...
>>>> Is there a pre-defined variable that returns the GET line
>>>> 
>>>> (http://www.php.net/index.php?everythingafterthequestionmark) as a
>>>> single variable (rather than individual variables)?

>>> os.environment('QUERY_STRING')

>SDD> Maybe you mean:
>SDD>     os.environ['USER']

Let's take the best of both:

os.environ['QUERY_STRING']
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From maymunbeyin at gmail.com  Fri Jul 24 14:51:54 2009
From: maymunbeyin at gmail.com (kk)
Date: Fri, 24 Jul 2009 11:51:54 -0700 (PDT)
Subject: How can I get the line number ?
Message-ID: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>

Hello

I am writing some Python code that runs in another application(has
wrapper functions). Due to lack of debugging I am printing out alot of
outputs and manual messages. I want to be able to create a function
that would let me print the current line number that is called from.
This is not for debugging exceptions it is rather to simplify my debug
messages, at least I can trace my debug messages.

thanks




From tjreedy at udel.edu  Fri Jul 24 14:52:38 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 14:52:38 -0400
Subject: len() should always return something
In-Reply-To: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
Message-ID: <h4cvtm$grr$1@ger.gmane.org>

Phillip M. Feldman wrote:

> I've been converting Matlab codes to Python.  In Matlab, a scalar is 
> just a one-by-one matrix and has a length of 1.  This convention seems 
> no less arbitrary to me than Python's convention that the concept of 
> length is not applicable to ints and floats.

Multiplication of a vector/matrix by a scalar always defined and 
commutative. Multiplication of a vector/matrix by a 1x1 matrix is not 
always even defined. So not having scalars in a matrix package strikes 
me as a bit odd.

 > My workaround was to write
> the following function:
> 
> def is_scalar(x):
>    """Return True if x is an instance of int, float, or complex.
>    Otherwise, return False.  Note: If x is a length-1 list or array
>    containing an int, float, or complex value, False is returned."""
>    if isinstance(x,int) or isinstance(x,float) or isinstance(x,complex):

Better:    if isinstance(x, (int, float, complex)):

but you forgot decimals and fractions and any other possible number modules.

In 3.1,
 >>> from numbers import Number
 >>> from decimal import Decimal
 >>> from fractions import Fraction
 >>> for x in 1, 1.0, (1+0j), Decimal(1), Fraction(1,1):
	isinstance(x, Number)

	
True
True
True
True
True

and the same for any other module that registers a class as a Number

>       return True
>    return False
> 
> The application is the following: In various types of scientific 
> applications, one operates on a list of measurements.  If there is only 
> a single measurement, it is reasonable to allow the calling program to 
> pass a scalar without wrapping it up into a list or array.

If you want to do that, start with

def f(x):
   try: len(x)
   except TypeError: x = x,

or in 3.1 use Number test above.

Terry Jan Reedy



From mkhitrov at gmail.com  Fri Jul 24 14:59:04 2009
From: mkhitrov at gmail.com (Maxim Khitrov)
Date: Fri, 24 Jul 2009 14:59:04 -0400
Subject: How can I get the line number ?
In-Reply-To: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>
References: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>
Message-ID: <26ddd1750907241159q3799e4c7k5a883d3b45feb4a5@mail.gmail.com>

On Fri, Jul 24, 2009 at 2:51 PM, kk<maymunbeyin at gmail.com> wrote:
> Hello
>
> I am writing some Python code that runs in another application(has
> wrapper functions). Due to lack of debugging I am printing out alot of
> outputs and manual messages. I want to be able to create a function
> that would let me print the current line number that is called from.
> This is not for debugging exceptions it is rather to simplify my debug
> messages, at least I can trace my debug messages.
>
> thanks

Modify the following as needed:

from inspect import currentframe, getframeinfo

def caller_info(depth=0):
	"""
	Get file, line number, and name of the calling function.
	"""
	if depth < 0:
		raise ValueError('invalid stack depth')

	caller = frame = currentframe()
	try:
		for i in xrange(-1, depth):
			caller = caller.f_back
			if caller is None:
				return (None, None, None)

		return getframeinfo(caller, 0)[:3]
	finally:
		del caller, frame

- Max


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 14:59:40 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 18:59:40 GMT
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <0279f596$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:

>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
> 
> and len("7") must return 8, by the same token... but wait!
> 
>  >>> len("7")
> 1
>  >>>
>  >>>
> my python installation must me outdated ;-)

No no no, you're obviously using an awesome version of Python that can 
compress single-character strings to a single bit!



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:00:14 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:00:14 GMT
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
Message-ID: <0279f5b9$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 15:55:45 +0200, Hrvoje Niksic wrote:

> The term "variable" is used in the Python
> language reference and elsewhere, and is quite compatible with how other
> popular languages (Java, PHP, Lisp, ...) use it.  Please stop
> complaining about valid terminology; it is not helpful.

No, the use of the single term "variable" to describe two distinct 
program models is not helpful. Whether other languages muddy the water 
between memory-location based variables and name-binding is irrelevant to 
whether we should do so. And quite a few of us are disappointed that the 
Python language reference should confuse the issue by using misleading 
terminology.

Unfortunately, the use of "variable" is so ingrained, and so simple 
compared to name binding terminology, that I fear we'll never eradicate 
it. I know sometimes I use it myself, but always with a little shiver of 
shame that I'm misusing terminology.



-- 
Steven


From robert.kern at gmail.com  Fri Jul 24 15:01:47 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 24 Jul 2009 14:01:47 -0500
Subject: Convert points to polygon shapefile
In-Reply-To: <20090724101638.E93B414B2A@smtp3.ualg.pt>
References: <20090724101638.E93B414B2A@smtp3.ualg.pt>
Message-ID: <h4d0er$hkh$1@ger.gmane.org>

On 2009-07-24 05:21, Luis Pedro Almeida wrote:
> Dear all,
>
> I would like to know how to convert a list of points into a polygon
> shapefile (esri).

shapelib has Python bindings.

   http://shapelib.maptools.org/

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From roy at panix.com  Fri Jul 24 15:03:29 2009
From: roy at panix.com (Roy Smith)
Date: Fri, 24 Jul 2009 15:03:29 -0400
Subject: list vs. tuple [Re: len() should always return something]
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<mailman.3674.1248461573.8015.python-list@python.org>
Message-ID: <roy-89AEB3.15032824072009@news.panix.com>

In article <mailman.3674.1248461573.8015.python-list at python.org>,
 Terry Reedy <tjreedy at udel.edu> wrote:

> Better:    if isinstance(x, (int, float, complex)):

I never noticed this before, but it seems odd that the second argument to 
isinstance() should be a tuple.  Using the normal arguments made about 
tuples vs. lists, it seems like a list would be the right data structure 
here.  I suppose a set would be even more right, but (I'm pretty sure) 
isinstance() predates sets.

I'm curious why a tuple was chosen.


From roy at panix.com  Fri Jul 24 15:04:55 2009
From: roy at panix.com (Roy Smith)
Date: Fri, 24 Jul 2009 15:04:55 -0400
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <roy-B8E460.15045524072009@news.panix.com>

In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
 Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:

> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
> 
> >> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
> > 
> > and len("7") must return 8, by the same token... but wait!
> > 
> >  >>> len("7")
> > 1
> >  >>>
> >  >>>
> > my python installation must me outdated ;-)
> 
> No no no, you're obviously using an awesome version of Python that can 
> compress single-character strings to a single bit!

Compressing strings to a single bit is easy.  It's the uncompressing that's 
tricky.


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:05:11 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:05:11 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
Message-ID: <0279f6df$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 00:02:28 -0700, Chris Rebert wrote:

> On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
> Feldman<pfeldman at verizon.net> wrote:
>>
>> Some aspects of the Python design are remarkably clever, while others
>> leave me perplexed. Here's an example of the latter: Why does len()
>> give an error when applied to an int or float? len() should always
>> return something; in particular, when applied to a scalar, it should
>> return a value of 1. Of course, I can define my own function like this:
>>
>> def mylen(x):
>> ? if isinstance(x,int) or isinstance(x,float): return 1 return len(x)
>>
>> But, this shouldn't be necessary.
> 
> The problem is that redefining len()/length/size that way would violate
> several principles of Python's design (The "Zen" of Python -
> http://www.python.org/dev/peps/pep-0020/).
> 
> Specifically:
> - Explicit is better than implicit.
> - Special cases aren't special enough to break the rules. 
> - Errors should never pass silently.
> - In the face of ambiguity, refuse the temptation to guess.


Chris, I'm curious why you think that these Zen are relevant to the OP's 
complaint.

Re explicit vs implicit, len(42) is just as explicit as len([42, 23]).

Arguably (I wouldn't argue this, but some people might) ints aren't 
"special enough" to break the rule that len(obj) should always return 
something.

(I don't actually agree, but some people might be able to produce a 
coherent argument why len() should apply equally to all objects.)

Re errors passing silently, the OP doesn't believe that len(42) should be 
an error, so that's not relevant.

And there's nothing ambiguous about len(42).

I agree with the current Python behaviour, but I don't think there's 
anything in the Zen to support it. As far as I know, there is no 
programming language which treats scalars like ints as if they were 
vectors of length 1, which makes Python's choice to make ints unlengthed 
a no-brainer.



-- 
Steven


From andre.roberge at gmail.com  Fri Jul 24 15:07:32 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Fri, 24 Jul 2009 12:07:32 -0700 (PDT)
Subject: ElementTree's Element substitution in Python 3
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
Message-ID: <9923e1c2-aabe-40d3-9c55-830991ad2dc9@q11g2000yqi.googlegroups.com>

Sorry for replying to myself ...  the following seems to be a working
solution to my original problem.
On Jul 24, 2:54?pm, Andr? <andre.robe... at gmail.com> wrote:
> I have a function to replace the content of an ElementTree Element by
> that of another one which works using Python 2 but not with Python 3.
> I get an assertion error. ?The function is as follows:
>
> def replace_element(elem, replacement):
> ? ? '''replace the content of an ElementTree Element by that of
> another
> ? ? ? ?one.
> ? ? '''
> ? ? elem.clear()
> ? ? elem.text = replacement.text
> ? ? elem.tail = replacement.tail
> ? ? elem.tag = replacement.tag
> ? ? elem.attrib = replacement.attrib
> ? ? elem[:] = replacement[:]
>

Use instead:

def replace_element(elem, replacement):
    '''replace the content of an ElementTree Element by that of
another
       one.
    '''
    elem.clear()
    elem.text = replacement.text
    elem.tail = replacement.tail
    elem.tag = replacement.tag
    elem.attrib = replacement.attrib
    try:
        elem[:] = replacement[:]  # works with Python 2.x (fast) but
not 3.x
    except AssertionError:
        del elem[:]
        for child in replacement:
            elem.append(child)


Andr?


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:11:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:11:33 GMT
Subject: exceptions.TypeError an integer is required
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
Message-ID: <0279f85d$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 11:24:58 -0700, jakecjacobson wrote:

> I am trying to do a post to a REST API over HTTPS and requires the
> script to pass a cert to the server.  I am getting "exceptions.TypeError
> an integer is required" error and can't find the reason.  I commenting
> out the lines of code, it is happening on the connection.request() line.
>  Here is the problem code.  Would love some help if possible.

Please post the traceback that you get.

My guess is that you are passing a string instead of an integer, probably 
for the port.


[...]
> 	except:
> 		print sys.exc_type, sys.exc_value

As a general rule, a bare except of that fashion is bad practice. Unless 
you can explain why it is normally bad practice, *and* why your case is 
an exception (no pun intended) to the rule "never use bare except 
clauses", I suggest you either:

* replace "except:" with "except Exception:" instead.

* better still, re-write the entire try block as:


    try:
        [code goes here]
    finally:
        connection.close()

and use the Python error-reporting mechanism instead of defeating it.



-- 
Steven


From piet at cs.uu.nl  Fri Jul 24 15:17:10 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 21:17:10 +0200
Subject: ElementTree's Element substitution in Python 3
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
Message-ID: <m2d47phow9.fsf@cs.uu.nl>

>>>>> Andr? <andre.roberge at gmail.com> (A) a ?crit:

>A> I have a function to replace the content of an ElementTree Element by
>A> that of another one which works using Python 2 but not with Python 3.
>A> I get an assertion error.  The function is as follows:

>A> def replace_element(elem, replacement):
>A>     '''replace the content of an ElementTree Element by that of
>A> another
>A>        one.
>A>     '''
>A>     elem.clear()
>A>     elem.text = replacement.text
>A>     elem.tail = replacement.tail
>A>     elem.tag = replacement.tag
>A>     elem.attrib = replacement.attrib
>A>     elem[:] = replacement[:]

>A> The last line is problematic.  For example, if I do the following
>A> program with Python2.5
>A> ###
>A> from xml.etree import ElementTree as et

>A> a = et.Element('a')
>A> b = et.SubElement(a, 'b')
>A> c = et.Element('c')

>A> a[:] = c[:]
>A> ###
>A> nothing of note happens - however, doing the same with Python 3.1, I
>A> get the following traceback:

>A> Traceback (most recent call last):
>A>   File "test.py", line 7, in <module>
>A>     a[:] = c[:]
>A>   File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
>A> 210, in __setitem__
>A>     assert iselement(element)
>A> AssertionError

This is a Python bug. Please report it. The problem is that in Python 3
slice assignments are done with __setitem__ rather than __setslice__ but
ElementTree has not been adapted to that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From tjreedy at udel.edu  Fri Jul 24 15:17:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 15:17:15 -0400
Subject: Adding method from one class to another class or to instance
	of    another class
In-Reply-To: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
References: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
Message-ID: <h4d1br$ldd$1@ger.gmane.org>

marekw2143 wrote:
> Hi,
> 
> I have one class (A) that has defined method createVars. I would like
> to add that method to class B
> The code looks like this:
> 
> 
> class A(object):
>    def createVars(self):
>       self.v1 = 1
>       self.v2 = 3
>       pass
> 
> class B(object):
>    pass
> 
> 
> I don't want to use inheritance (because class A has many methods
> defined that class B doesn't need).
> When I try the folloowing:
> 
> 
> B.createVars = C.createVars

  you meant A.createVars

> B().createVars()
> 
> 
> then the following error occurs:
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unbound method createVars() must be called with A instance
> as first argument (got nothing instead)

In 3.1, your example works fine. The difference is that in 2.x, 
B.createVars is a method wrapperthat wraps the function, whereas in 3.1, 
it is the function itself. For 2.x, you need to extract the function 
from the wrapper. It is im_func or something like that. Use 
dir(B.createVars) to check for sure.

> How can I solve this problem?

Terry Jan Reedy



From linuxguy123 at gmail.com  Fri Jul 24 15:17:24 2009
From: linuxguy123 at gmail.com (Linuxguy123)
Date: Fri, 24 Jul 2009 13:17:24 -0600
Subject: Eclipse Pydev update error ?
Message-ID: <1248463044.8697.50.camel@localhost.localdomain>

Does anyone know why this error is occurring in my Eclipse Pydev
update ?

An error occurred while collecting items to be installed
  No repository found containing:
org.python.pydev/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.ast/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.core/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.debug/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.feature/org.eclipse.update.feature/1.4.7.2843
  No repository found containing:
org.python.pydev.help/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.jython/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.parser/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.refactoring/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.templates/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.customizations/osgi.bundle/1.4.7.2843

Thanks




From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:18:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:18:09 GMT
Subject: list vs. tuple [Re: len() should always return something]
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<mailman.3674.1248461573.8015.python-list@python.org>
	<roy-89AEB3.15032824072009@news.panix.com>
Message-ID: <0279f9e9$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 15:03:29 -0400, Roy Smith wrote:

> In article <mailman.3674.1248461573.8015.python-list at python.org>,
>  Terry Reedy <tjreedy at udel.edu> wrote:
> 
>> Better:    if isinstance(x, (int, float, complex)):
> 
> I never noticed this before, but it seems odd that the second argument
> to isinstance() should be a tuple.  Using the normal arguments made
> about tuples vs. lists, it seems like a list would be the right data
> structure here.

What would be the point of using a list? You're never going to sort it, 
or append items to it, or otherwise mutate it. You build it, pass it to a 
function which doesn't modify it in any fashion, then it gets garbage 
collected.


> I suppose a set would be even more right, but (I'm
> pretty sure) isinstance() predates sets.

Yes.

[steve at sylar ~]$ python1.5
Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
4.1.2-27)] on linux2
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>> isinstance
<built-in function isinstance>
>>> set
Traceback (innermost last):
  File "<stdin>", line 1, in ?
NameError: set



> I'm curious why a tuple was chosen.

Tuples are smaller and faster to build than lists -- they're the most 
lightweight sequence type in Python. You don't need all the extra 
functionality of lists, so why go to the time and effort of building a 
list?




-- 
Steven


From maymunbeyin at gmail.com  Fri Jul 24 15:23:58 2009
From: maymunbeyin at gmail.com (kk)
Date: Fri, 24 Jul 2009 12:23:58 -0700 (PDT)
Subject: How can I get the line number ?
References: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>
	<mailman.3675.1248461967.8015.python-list@python.org>
Message-ID: <3ce2fe1a-c769-4f92-b4b0-559229158297@33g2000vbe.googlegroups.com>

Maxim,

Thank you so much. I will try right now.


From fabiofz at gmail.com  Fri Jul 24 15:43:36 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Fri, 24 Jul 2009 16:43:36 -0300
Subject: Eclipse Pydev update error ?
In-Reply-To: <1248463044.8697.50.camel@localhost.localdomain>
References: <1248463044.8697.50.camel@localhost.localdomain>
Message-ID: <cfb578b20907241243ld649df0gc19342c241810ec4@mail.gmail.com>

On Fri, Jul 24, 2009 at 4:17 PM, Linuxguy123<linuxguy123 at gmail.com> wrote:
> Does anyone know why this error is occurring in my Eclipse Pydev
> update ?
>
> An error occurred while collecting items to be installed
> ?No repository found containing:
> org.python.pydev/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.ast/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.core/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.debug/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.feature/org.eclipse.update.feature/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.help/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.jython/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.parser/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.refactoring/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.templates/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.customizations/osgi.bundle/1.4.7.2843
>

This usually happens if there was some connection error during the
update. You can try other mirrors (see:
http://pydev.blogspot.com/2009/07/pydev-147-released.html for the new
added mirrors).

Cheers,

Fabio


From tjreedy at udel.edu  Fri Jul 24 15:45:36 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 15:45:36 -0400
Subject: ElementTree's Element substitution in Python 3
In-Reply-To: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
Message-ID: <h4d311$qkd$1@ger.gmane.org>

Andr? wrote:
> I have a function to replace the content of an ElementTree Element by
> that of another one which works using Python 2 but not with Python 3.
> I get an assertion error.  The function is as follows:
> 
> def replace_element(elem, replacement):
>     '''replace the content of an ElementTree Element by that of
> another
>        one.
>     '''
>     elem.clear()
>     elem.text = replacement.text
>     elem.tail = replacement.tail
>     elem.tag = replacement.tag
>     elem.attrib = replacement.attrib
>     elem[:] = replacement[:]
> 
> The last line is problematic.  For example, if I do the following
> program with Python2.5
> ###
> from xml.etree import ElementTree as et
> 
> a = et.Element('a')
> b = et.SubElement(a, 'b')
> c = et.Element('c')
> 
> a[:] = c[:]
> ###
> nothing of note happens - however, doing the same with Python 3.1, I
> get the following traceback:
> 
> Traceback (most recent call last):
>   File "test.py", line 7, in <module>
>     a[:] = c[:]
>   File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
> 210, in __setitem__
>     assert iselement(element)
> AssertionError
> 
> ======
> I would gladly welcome any suggestion for writing a replace_element()
> function that works with Python 3.1

My guess is that you found a subtle bug in the 3.1 version of 
ElementTree, perhap a result of conversion. I would take a look at the 
noted line 210 to see whether it is 'a' or 'c' that is not passing as an 
element. Assuming that it is 'c', I would look at __getitem__ to see why 
not. Is [:] special-cased? Compare the codes for 2.5 and 3.1. Assuming 
it still looks like a bug, report it on the tracker using your minimal 
example, leaving out your function.

tjr



From tjreedy at udel.edu  Fri Jul 24 15:47:36 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 15:47:36 -0400
Subject: exceptions.TypeError an integer is required
In-Reply-To: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
Message-ID: <h4d34n$qkd$2@ger.gmane.org>

jakecjacobson wrote:
> I am trying to do a post to a REST API over HTTPS and requires the
> script to pass a cert to the server.  I am getting
> "exceptions.TypeError an integer is required" error and can't find the
> reason.  I commenting out the lines of code, it is happening on the
> connection.request() line.  Here is the problem code.  Would love some
> help if possible.
> 
> 	head = {"Content-Type" : "application/x-www-form-urlencoded",
> "Accept" : "text/plain"}
> 	parameters = urlencode({"collection" : collection, "entryxml" : open
> (file,'r').read()})
> 	try:
> 		connection = httplib.HTTPSConnection(host, port, key_file,
> cert_file)
> 		connection.request('POST', path, parameters, head)
> 		response = connection.getresponse()
> 		print response.status, response.reason
> 	except:
> 		print sys.exc_type, sys.exc_value
> 
> 	connection.close()

Help us help you by posting the full actual traceback.



From andre.roberge at gmail.com  Fri Jul 24 15:48:02 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Fri, 24 Jul 2009 12:48:02 -0700 (PDT)
Subject: ElementTree's Element substitution in Python 3
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
	<m2d47phow9.fsf@cs.uu.nl>
Message-ID: <7ea510e0-ceb8-4425-9af2-b30154ad6e6d@b14g2000yqd.googlegroups.com>

On Jul 24, 4:17?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Andr? <andre.robe... at gmail.com> (A) a ?crit:
> >A> I have a function to replace the content of an ElementTree Element by
> >A> that of another one which works using Python 2 but not with Python 3.
> >A> I get an assertion error.

[SNIP]

> >A> Traceback (most recent call last):
> >A> ? File "test.py", line 7, in <module>
> >A> ? ? a[:] = c[:]
> >A> ? File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
> >A> 210, in __setitem__
> >A> ? ? assert iselement(element)
> >A> AssertionError
>
> This is a Python bug. Please report it.

Done.

> The problem is that in Python 3
> slice assignments are done with __setitem__ rather than __setslice__ but
> ElementTree has not been adapted to that.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org



From linuxguy123 at gmail.com  Fri Jul 24 15:57:40 2009
From: linuxguy123 at gmail.com (Linuxguy123)
Date: Fri, 24 Jul 2009 13:57:40 -0600
Subject: Eclipse Pydev update error ?
In-Reply-To: <cfb578b20907241243ld649df0gc19342c241810ec4@mail.gmail.com>
References: <1248463044.8697.50.camel@localhost.localdomain>
	<cfb578b20907241243ld649df0gc19342c241810ec4@mail.gmail.com>
Message-ID: <1248465460.8697.51.camel@localhost.localdomain>

On Fri, 2009-07-24 at 16:43 -0300, Fabio Zadrozny wrote:
> On Fri, Jul 24, 2009 at 4:17 PM, Linuxguy123<linuxguy123 at gmail.com> wrote:
> > Does anyone know why this error is occurring in my Eclipse Pydev
> > update ?
> >
> > An error occurred while collecting items to be installed
> >  No repository found containing:
> > org.python.pydev/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.ast/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.core/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.debug/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.feature/org.eclipse.update.feature/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.help/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.jython/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.parser/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.refactoring/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.templates/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.customizations/osgi.bundle/1.4.7.2843
> >
> 
> This usually happens if there was some connection error during the
> update. You can try other mirrors (see:
> http://pydev.blogspot.com/2009/07/pydev-147-released.html for the new
> added mirrors).

Excellent reply.  Thanks.

I added http://fabioz.com/pydev/updates to my site list and the update
completed immediately.

I'll bookmark the blog as well.

Thanks again.




From clp2 at rebertia.com  Fri Jul 24 16:02:24 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 13:02:24 -0700
Subject: len() should always return something
In-Reply-To: <0279f6df$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <50697b2c0907241302m166d0c61y4912a29aaa4caaf1@mail.gmail.com>

On Fri, Jul 24, 2009 at 12:05 PM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Fri, 24 Jul 2009 00:02:28 -0700, Chris Rebert wrote:
>
>> On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
>> Feldman<pfeldman at verizon.net> wrote:
>>>
>>> Some aspects of the Python design are remarkably clever, while others
>>> leave me perplexed. Here's an example of the latter: Why does len()
>>> give an error when applied to an int or float? len() should always
>>> return something; in particular, when applied to a scalar, it should
>>> return a value of 1. Of course, I can define my own function like this:
>>>
>>> def mylen(x):
>>> ? if isinstance(x,int) or isinstance(x,float): return 1 return len(x)
>>>
>>> But, this shouldn't be necessary.
>>
>> The problem is that redefining len()/length/size that way would violate
>> several principles of Python's design (The "Zen" of Python -
>> http://www.python.org/dev/peps/pep-0020/).
>>
>> Specifically:
>> - Explicit is better than implicit.
>> - Special cases aren't special enough to break the rules.
>> - Errors should never pass silently.
>> - In the face of ambiguity, refuse the temptation to guess.
>
>
> Chris, I'm curious why you think that these Zen are relevant to the OP's
> complaint.

To explain in more detail:

> Re explicit vs implicit, len(42) is just as explicit as len([42, 23]).

If you want a collection (something that has length), then one should
explicitly create one, not implicitly have a singleton value act like
it's a pseudo-collection.
I admit I'm somewhat conflating this principle with the anti-ambiguity
principle, but the two are related, imho.

> Arguably (I wouldn't argue this, but some people might) ints aren't
> "special enough" to break the rule that len(obj) should always return
> something.

Except that's not the current rule. The current rule is that it's
defined only for collections.
One would instead have to argue why ints are special enough to have
len() defined despite not being collections.
I think the point made by Grant Edwards is instructive. len(x) = 1
typically implies list(x)[0] and similar should be valid. Altering the
behavior would invalidate that theorem and cause quite a bit of code
upheaval, all just to save the OP from typing one pair of []s.

> (I don't actually agree, but some people might be able to produce a
> coherent argument why len() should apply equally to all objects.)

Well, yes, this /whole/ "argument" is entirely academic; the behavior
is extremely unlikely to change, we're just trying to give ex post
facto rationales for pedagogical purposes. :)

> Re errors passing silently, the OP doesn't believe that len(42) should be
> an error, so that's not relevant.

True, it would not directly silence an error, but defining len() on
scalars would tend towards obscuring errors in code that incorrectly
treats scalars as collections.

> And there's nothing ambiguous about len(42).

Really? What is its value then? I think arguments of varying quality
can be made for:
1 - as the OP and those from array programming languages would suggest
2 - the number of decimal digits in 42, if one was feeling Perlish
6 - the minimum number of bits necessary to represent 42 in binary
32 (or 64, depending on your CPU) - the number of bits necessary to
represent an int (obviously breaks down a bit with arbitrary-magnitude
ints)
undefined - i.e. it causes an error, the current behavior; asking for
the length of a non-collection is "nonsensical" or "absurd"

> I agree with the current Python behaviour, but I don't think there's
> anything in the Zen to support it. As far as I know, there is no

The problem and strength of the Zen is that it's all about how you
interpret it. :-)

Cheers,
Chris
-- 
http://blog.rebertia.com


From marcusw at cox.net  Fri Jul 24 16:09:15 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 24 Jul 2009 16:09:15 -0400
Subject: len() should always return something
In-Reply-To: <roy-B8E460.15045524072009@news.panix.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
	<roy-B8E460.15045524072009@news.panix.com>
Message-ID: <h4d4dc$jav$1@adenine.netfront.net>

On 7/24/2009 3:04 PM, Roy Smith wrote:
> In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
>  Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
> 
>> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
>>
>>>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
>>> and len("7") must return 8, by the same token... but wait!
>>>
>>>  >>> len("7")
>>> 1
>>>  >>>
>>>  >>>
>>> my python installation must me outdated ;-)
>> No no no, you're obviously using an awesome version of Python that can 
>> compress single-character strings to a single bit!
> 
> Compressing strings to a single bit is easy.  It's the uncompressing that's 
> tricky.
I assume you mean ord("7")%2?

First one to correctly decompress the value 0 into an ASCII character 
wins the title of the world's most capable hacker :p

Marcus


From breamoreboy at yahoo.co.uk  Fri Jul 24 16:18:26 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 24 Jul 2009 21:18:26 +0100
Subject: len() should always return something
In-Reply-To: <h4d4dc$jav$1@adenine.netfront.net>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>	<mailman.3661.1248444714.8015.python-list@python.org>	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>	<0279f596$0$5185$c3e8da3@news.astraweb.com>	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
Message-ID: <h4d4ti$ug$1@ger.gmane.org>

Marcus Wanner wrote:
> On 7/24/2009 3:04 PM, Roy Smith wrote:
>> In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
>>  Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
>>
>>> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
>>>
>>>>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
>>>> and len("7") must return 8, by the same token... but wait!
>>>>
>>>>  >>> len("7")
>>>> 1
>>>>  >>>
>>>>  >>>
>>>> my python installation must me outdated ;-)
>>> No no no, you're obviously using an awesome version of Python that 
>>> can compress single-character strings to a single bit!
>>
>> Compressing strings to a single bit is easy.  It's the uncompressing 
>> that's tricky.
> I assume you mean ord("7")%2?
> 
> First one to correctly decompress the value 0 into an ASCII character 
> wins the title of the world's most capable hacker :p
> 
> Marcus
asciichar = chr(len(0)) if the OP's wishes come true?

-- 
Kindest regards.

Mark Lawrence.



From marcusw at cox.net  Fri Jul 24 16:25:57 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 24 Jul 2009 16:25:57 -0400
Subject: len() should always return something
In-Reply-To: <mailman.3684.1248466691.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>	<mailman.3661.1248444714.8015.python-list@python.org>	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>	<0279f596$0$5185$c3e8da3@news.astraweb.com>	<roy-B8E460.15045524072009@news.panix.com>	<h4d4dc$jav$1@adenine.netfront.net>
	<mailman.3684.1248466691.8015.python-list@python.org>
Message-ID: <h4d5cm$jav$2@adenine.netfront.net>

On 7/24/2009 4:18 PM, Mark Lawrence wrote:
> Marcus Wanner wrote:
>> On 7/24/2009 3:04 PM, Roy Smith wrote:
>>> In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
>>>  Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
>>>
>>>> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
>>>>
>>>>>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
>>>>> and len("7") must return 8, by the same token... but wait!
>>>>>
>>>>>  >>> len("7")
>>>>> 1
>>>>>  >>>
>>>>>  >>>
>>>>> my python installation must me outdated ;-)
>>>> No no no, you're obviously using an awesome version of Python that 
>>>> can compress single-character strings to a single bit!
>>>
>>> Compressing strings to a single bit is easy.  It's the uncompressing 
>>> that's tricky.
>> I assume you mean ord("7")%2?
>>
>> First one to correctly decompress the value 0 into an ASCII character 
>> wins the title of the world's most capable hacker :p
>>
>> Marcus
> asciichar = chr(len(0)) if the OP's wishes come true?
> 
Nope, wasn't "?"...

Marcus


From python.list at tim.thechases.com  Fri Jul 24 16:30:10 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 24 Jul 2009 15:30:10 -0500
Subject: len() should always return something
In-Reply-To: <h4d4dc$jav$1@adenine.netfront.net>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>	<mailman.3661.1248444714.8015.python-list@python.org>	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>	<0279f596$0$5185$c3e8da3@news.astraweb.com>	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
Message-ID: <4A6A19D2.2020204@tim.thechases.com>

Marcus Wanner wrote:
> First one to correctly decompress the value 0 into an ASCII
> character wins the title of the world's most capable hacker :p

Bah...uncompressing the value 0 into *an* ASCII character is 
easy.  Uncompressing it into the *original* ASCII character from 
which it was compressed (with the aforementioned compression 
method) becomes a bit trickier ;-)

-tkc





From clp2 at rebertia.com  Fri Jul 24 16:34:11 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 13:34:11 -0700
Subject: len() should always return something
In-Reply-To: <4A6A19D2.2020204@tim.thechases.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
	<4A6A19D2.2020204@tim.thechases.com>
Message-ID: <50697b2c0907241334t660fce21l3ae20e7772561cef@mail.gmail.com>

On Fri, Jul 24, 2009 at 1:30 PM, Tim Chase<python.list at tim.thechases.com> wrote:
> Marcus Wanner wrote:
>>
>> First one to correctly decompress the value 0 into an ASCII
>> character wins the title of the world's most capable hacker :p
>
> Bah...uncompressing the value 0 into *an* ASCII character is easy.
> ?Uncompressing it into the *original* ASCII character from which it was
> compressed (with the aforementioned compression method) becomes a bit
> trickier ;-)

Deja vu: http://www.hackles.org/cgi-bin/archives.pl?request=310

- Chris
-- 
http://blog.rebertia.com


From tismer at stackless.com  Fri Jul 24 16:39:36 2009
From: tismer at stackless.com (Christian Tismer)
Date: Fri, 24 Jul 2009 13:39:36 -0700
Subject: ANN: psyco V2
In-Reply-To: <4a696af3$0$442$426a74cc@news.free.fr>
References: <mailman.3252.1247798900.8015.python-list@python.org>	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>	<mailman.3613.1248368814.8015.python-list@python.org>
	<4a696af3$0$442$426a74cc@news.free.fr>
Message-ID: <4A6A1C08.6000202@stackless.com>

On 7/24/09 1:04 AM, William Dode wrote:
> On 23-07-2009, Christian Tismer wrote:
...

>> Wasn't the project plan saying the opposite, borrowing
>> some ideas from psyco? :-)
>> http://code.google.com/p/unladen-swallow/wiki/ProjectPlan
>
> How do you see the future of psyco when unladen-swallow will grab the
> best of psyco (if they can !) ?

I have no objections, but also no idea so far how that could work.
Sounded like an unreflected idea to me, without seriously
checking the possibilities and/or implications. The same
kind of research apparently did not happen concerning PyPy,
which IMHO is much more suitable to take advantage from.

This is for the current status of psyco, of course.
It will change dramatically in the next months, slowly
adopting some of PyPy's ideas. Then it might start to
make more sense.

> Wait and see ?

Wait and see, not holding breath, I'd say.

> Anyway, thanks a lot for your work that we can use NOW !

Thanks for so much encouraging reactions!

cheers - chris
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From tjreedy at udel.edu  Fri Jul 24 16:43:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 16:43:17 -0400
Subject: list vs. tuple [Re: len() should always return something]
In-Reply-To: <0279f9e9$0$5185$c3e8da3@news.astraweb.com>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>	<mailman.3674.1248461573.8015.python-list@python.org>	<roy-89AEB3.15032824072009@news.panix.com>
	<0279f9e9$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4d6d5$5gs$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 24 Jul 2009 15:03:29 -0400, Roy Smith wrote:
> 
>> In article <mailman.3674.1248461573.8015.python-list at python.org>,
>>  Terry Reedy <tjreedy at udel.edu> wrote:
>>
>>> Better:    if isinstance(x, (int, float, complex)):
>> I never noticed this before, but it seems odd that the second argument
>> to isinstance() should be a tuple.  Using the normal arguments made
>> about tuples vs. lists, it seems like a list would be the right data
>> structure here.

I ignore the 'normal arguments' and it seems that Guido or the designer 
of isinstance did so here too.  Fortunately.  Practicality beats 
'purity', especially misguided purity.

> What would be the point of using a list? You're never going to sort it, 
> or append items to it, or otherwise mutate it. You build it, pass it to a 
> function which doesn't modify it in any fashion, then it gets garbage 
> collected.
> 
> 
>> I suppose a set would be even more right, but (I'm
>> pretty sure) isinstance() predates sets.
> 
> Yes.
> 
> [steve at sylar ~]$ python1.5
> Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
> 4.1.2-27)] on linux2
> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>> isinstance
> <built-in function isinstance>
>>>> set
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
> NameError: set
> 
> 
> 
>> I'm curious why a tuple was chosen.
> 
> Tuples are smaller and faster to build than lists -- they're the most 
> lightweight sequence type in Python. You don't need all the extra 
> functionality of lists, so why go to the time and effort of building a 
> list?

In fact, constant tuples can be and now are compiled as constants:

 >>> dis(compile('(1,2,3)','','eval'))
   1           0 LOAD_CONST               3 ((1, 2, 3))
               3 RETURN_VALUE
 >>> dis(compile('[1,2,3]','','eval'))
   1           0 LOAD_CONST               0 (1)
               3 LOAD_CONST               1 (2)
               6 LOAD_CONST               2 (3)
               9 BUILD_LIST               3
              12 RETURN_VALUE

Internally, even a frozenset is more complicated than a tuple since it 
still needs a hash table, which is overkill for something that will be 
linearly scanned exactly once.

tjr



From qauzzix at gmail.com  Fri Jul 24 16:52:47 2009
From: qauzzix at gmail.com (Qauzzix)
Date: Fri, 24 Jul 2009 13:52:47 -0700 (PDT)
Subject: How do I generate dia diagrams from python source code?
Message-ID: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>

Greetings.

Since I have been using dia to make my UML diagrams. I also found an
util named dia2code that generates python code from dia diagram. Now
that I have that option I really want to find a way to generate dia
diagram from existing code and/or maintain my diagrams.

I have been googling  like crazy trying to find a way but with no
luck. Anyone here know how to do this?

Peace,
 - Jakob Sv. Bjarnason


From tjreedy at udel.edu  Fri Jul 24 16:52:53 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 16:52:53 -0400
Subject: len() should always return something
In-Reply-To: <50697b2c0907241302m166d0c61y4912a29aaa4caaf1@mail.gmail.com>
References: <24639361.post@talk.nabble.com>	<mailman.3645.1248418956.8015.python-list@python.org>	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<50697b2c0907241302m166d0c61y4912a29aaa4caaf1@mail.gmail.com>
Message-ID: <h4d6v5$75q$1@ger.gmane.org>

Chris Rebert wrote:

> I think the point made by Grant Edwards is instructive. len(x) = 1
> typically implies list(x)[0] and similar should be valid. 

At least, one should be able to iterate with x and get len(x) items.
See below.

>> And there's nothing ambiguous about len(42).
> 
> Really? What is its value then? I think arguments of varying quality
> can be made for:
> 1 - as the OP and those from array programming languages would suggest
> 2 - the number of decimal digits in 42, if one was feeling Perlish
> 6 - the minimum number of bits necessary to represent 42 in binary
> 32 (or 64, depending on your CPU) - the number of bits necessary to
> represent an int (obviously breaks down a bit with arbitrary-magnitude
> ints)
> undefined - i.e. it causes an error, the current behavior; asking for
> the length of a non-collection is "nonsensical" or "absurd"

In set theory, one can define counts recursively as follows
0 = {} (set, not dict)
n+1 = n | {n}
so len(n) = n, and in particular, len(42) = 42.

On the same basis, it has been proposed (and rejected) that iter(n) == 
range(n), do that we could write 'for i in 10' for instance. Guido 
thought this too esoteric.

Terry Jan Reedy



From tjreedy at udel.edu  Fri Jul 24 16:57:13 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 16:57:13 -0400
Subject: non-owning references?
In-Reply-To: <0279f5b9$0$5185$c3e8da3@news.astraweb.com>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<0279f5b9$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4d779$7u4$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 24 Jul 2009 15:55:45 +0200, Hrvoje Niksic wrote:
> 
>> The term "variable" is used in the Python
>> language reference and elsewhere, and is quite compatible with how other
>> popular languages (Java, PHP, Lisp, ...) use it.  Please stop
>> complaining about valid terminology; it is not helpful.
> 
> No, the use of the single term "variable" to describe two distinct 
> program models is not helpful. Whether other languages muddy the water 
> between memory-location based variables and name-binding is irrelevant to 
> whether we should do so. And quite a few of us are disappointed that the 
> Python language reference should confuse the issue by using misleading 
> terminology.
> 
> Unfortunately, the use of "variable" is so ingrained, and so simple 
> compared to name binding terminology, that I fear we'll never eradicate 
> it. I know sometimes I use it myself, but always with a little shiver of 
> shame that I'm misusing terminology.

Some years ago, I read a claim that 'variable' has about 15 shades of 
meaning in math (some referring to non-variable constants), making it 
probably the most overloaded term in math. I am trying to mostly avoid 
it in the book I am writing.

tjr




From bryanvick at gmail.com  Fri Jul 24 17:11:02 2009
From: bryanvick at gmail.com (Bryan)
Date: Fri, 24 Jul 2009 14:11:02 -0700 (PDT)
Subject: Script runs manually, but cron fails
Message-ID: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>

I have a backup script that runs fine when I run it manually from the
command line.  When I run it with cron, the script stops running at
random points in the source code.

The script calls rsync with the subprocess module, which in turn uses
ssh to backup files from a box on my lan.  It also uses the atexit
module to always run a certain piece of cleanup code when the script
exits.  However, this piece of code is never called when I use cron to
run the script, but a ps -A command also does not show the python
process so I know the script is dead.  The log files generated by the
script all show rsync as completing, but then the logging gets cutoff
at random places when the script dies after that point.  I am not
getting any email from cron complaining of an error either.

The script runs fine in my bash shell, what could cron be doing to
interfere?





From duncan.booth at invalid.invalid  Fri Jul 24 17:14:06 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 24 Jul 2009 21:14:06 GMT
Subject: list vs. tuple [Re: len() should always return something]
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<mailman.3674.1248461573.8015.python-list@python.org>
	<roy-89AEB3.15032824072009@news.panix.com>
Message-ID: <Xns9C52E231DF188duncanbooth@127.0.0.1>

Roy Smith <roy at panix.com> wrote:

> In article <mailman.3674.1248461573.8015.python-list at python.org>,
>  Terry Reedy <tjreedy at udel.edu> wrote:
> 
>> Better:    if isinstance(x, (int, float, complex)):
> 
> I never noticed this before, but it seems odd that the second argument
> to isinstance() should be a tuple.  Using the normal arguments made
> about tuples vs. lists, it seems like a list would be the right data
> structure here.  I suppose a set would be even more right, but (I'm
> pretty sure) isinstance() predates sets.
> 
> I'm curious why a tuple was chosen.

There's a very good reason[*]. The second argument to isinstance() is a 
classinfo where a classinfo is a type or a tuple of classinfo.

That means you can have an arbitrarily complex set of nested tuples e.g. 
(int, (float, complex)), but the immutable nature of tuples means the 
implementation of isinstance can walk the tuple tree without ever having to 
worry about infinite loops.

If classinfo could be a list of types then someone somewhere would feed it 
a recursive list and then complain that the interpreter crashed.

Exception specifications are tuples for the same reason.

[*] For some definition of 'very good'. Would Python be significantly 
impaired if you couldn't combine classinfos into a tree structure? Probably 
not.


From anonymous.c.lisper at gmail.com  Fri Jul 24 17:58:57 2009
From: anonymous.c.lisper at gmail.com (ACL)
Date: Fri, 24 Jul 2009 14:58:57 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
Message-ID: <12ce2d31-5028-4b60-a5b1-5d5bf1fc06d7@f20g2000prn.googlegroups.com>

On Jul 24, 2:06?pm, Raffael Cavallaro
<raffaelcavall... at pas.espam.s.il.vous.plait.mac.com> wrote:
> On 2009-07-23 23:51:02 -0400, Carl Banks <pavlovevide... at gmail.com> said:
>
> > On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
> >> fft1976 wrote:
> >>> How do you explain that something as inferior as Python beat Lisp in
> >>> the market place despite starting 40 years later.
>
> >> Probably due to similar reasons that lead php to become remotely relevant
> > .
>
> > Well, the only reason PHP became relevant because it was an
> > easy
>
> ^^^^^^^^
> ^^^^^^^^ (emphasis added)
>
> > to
> > deploy solution in a single application domain, the web, that happened
> > to explode.
>
> i.e., Python "beat" lisp because it is ~70% of lisp in a form that is
> much more palatable to the average programmer, just as php became
> popular because it is powerful enough to do websites and, most
> importantly, apprehensible to mediocre programmers and even some
> non-programmers.
>
> --
> Raffael Cavallaro

I actually think that the thing holding lisp back is 'bus factor'.

Lets assume I have a java project and a lisp project:

Java project:
I have maybe 10 or 12 people on my team working on various subsystems
of my project. There are probably one or two 'technical leader' types
in the group, and a bunch of others who are sort of 'serfs', banging
out java classes. Lets say one of my important guys gets totally
splattered by a bus... I've still got another one left! I can rely on
the other guy to keep things afloat while I train up a new leader
type.

Lisp project:
I don't need as many people. I have 3 or 4 people, and one person is
my technical leader and lisp guru. Guru is probably in charge of more
difficult macros and (because of that), also in charge of the overall
design (macros are design patterns embodied in code). Lets say he gets
totally annihilated by the bus. What do I do now? I had all my eggs in
one basket and my project is now stalled.

I think that (for example) when people are saying that lisp macros
make projects difficult to understand, or that lisp hackers are much
harder to find than other programmers, what they are really showing is
that because of the nature of the language, lisp projects get
organized in a different way. This different way of organization is
especially hard on corporate projects, because managers are expected
to plan for when some important guy drops dead.

The problem with lisp is that if you hire too many extra hackers, you
end up with a bunch of people sitting around twiddling their thumbs.

This may also explain why it gets touted as an academic language. In
academia if a professor who is leading some important research drops
dead, who cares? Most likely no one had interest as to whether the
university would make a profit on this particular research endeavor
(except maybe the deceased, as he would like to get grant funding).

So I guess then we can give some tips for making lisp more acceptable
for 'paying gigs'.
1.) If you are a lisp hacker, it is your duty to be lazier and write
less code. We need to make it so that these projects need sizable
teams of people to complete.

2.) Write down everything that you do, everything you are going to do.
Maybe draw some object diagrams of your important/fancy macros, make
sure these are stored with the source. (You'll note that an iterative
approach to programming isn't really conducive to making a lot of
diagrams of stuff...)

I don't know what this has to do with python or scheme or people
dumping scheme for python.
Honestly, I seriously doubt that any undergraduate programming course
will give you enough actual programming experience to make you
seriously proficient in the language (research projects not counted).
The language used to teach the material is a cursory detail.


From user at example.net  Fri Jul 24 18:28:09 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 00:28:09 +0200
Subject: pack an integer into a string
Message-ID: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>

is there a pythonic and synthetic way (maybe some standard module) to 
"pack" an integer (maybe a *VERY* big one) into a string? like this:

  >>> number = 252509952
  >>> hex(number)
  '0xf0cff00'
  >>>

so i would like a string like '\xf0\xcf\xf0\x00'

i wrote some code to do it, so ugly i am ashamed to post :-(

i tried xdrlib, but does not quite do what i mean...

bye


From martin at v.loewis.de  Fri Jul 24 18:28:24 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sat, 25 Jul 2009 00:28:24 +0200
Subject: installing 2.6 on vista64
In-Reply-To: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
References: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
Message-ID: <4a6a3588$0$11346$9b622d9e@news.freenet.de>

> I just downloaded and attempted to install python 2.6.2.  The
> installer proceeds to do its work then dies, leaving an entry in the
> eventlog:
> 
> Windows Installer installed the product. Product Name: Python 2.6.2.
> Product Version: 2.6.2150. Product Language: 1033. Installation
> success or error status: 1602.

Are you using subst'ed drives by any chance?

> Googling for this I wasn't able to narrow the results down to
> something usable. Anyone know of issues and how to fix them installing
> on vista 64 (yes, I have 8 gigs of ram)

Run "msiexec /i <pythonxy.msi> /l*v python.log", and search the log file
for 1602. This should give a clue.

Regards,
Martin


From emile at fenx.com  Fri Jul 24 18:41:59 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 24 Jul 2009 15:41:59 -0700
Subject: Script runs manually, but cron fails
In-Reply-To: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
References: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
Message-ID: <h4ddfr$o4h$1@ger.gmane.org>

On 7/24/2009 2:11 PM Bryan said...
> The script runs fine in my bash shell, what could cron be doing to
> interfere?

It's likely environmental -- make sure you're starting with the same 
path, etc.  Sometimes I'll create a sell script by env'ing to a bash 
script file and append the actual command to execute, chmod a+x the 
script and put that in the cron file.  Then strip out variables until 
you find the missing culprit.

HTH,

Emile





From sbassi at clubdelarazon.org  Fri Jul 24 18:43:58 2009
From: sbassi at clubdelarazon.org (Sebastian Bassi)
Date: Fri, 24 Jul 2009 19:43:58 -0300
Subject: pack an integer into a string
In-Reply-To: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <9e2f512b0907241543o5b4606agf80a87af74b4116@mail.gmail.com>

On Fri, Jul 24, 2009 at 7:28 PM, superpollo<user at example.net> wrote:
> is there a pythonic and synthetic way (maybe some standard module) to "pack"
> an integer (maybe a *VERY* big one) into a string? like this:

What do you mean to pack? Maybe Pickle is what you want.

import cPickle
variable = 124348654333577698
cPickle.dump(variable,open('filename', 'w'))

To load it:

import cPickle
vaariable = cPickle.load(open('filename'))

It is not "into a string", but instead of a filename, use a string with stringio


From 9372966370 at sms.mycricket.com  Fri Jul 24 18:51:49 2009
From: 9372966370 at sms.mycricket.com (9372966370 at sms.mycricket.com)
Date: 24 Jul 09 16:51:49 -0600
Subject: No subject
Message-ID: <200907242251.n6OLv34O026362@mta2-den.mycricket.com>

(Re: urllib2.URLError: <urlopen error unknown url type: 'http> error using
	twill with python)  how can i change url/http://...
 ---------------------------------------------
Sent by a Cricket mobile device
 ---------------------------------------------


From 9372966370 at sms.mycricket.com  Fri Jul 24 18:53:15 2009
From: 9372966370 at sms.mycricket.com (9372966370 at sms.mycricket.com)
Date: 24 Jul 09 16:53:15 -0600
Subject: No subject
Message-ID: <200907242253.n6OLv34f026362@mta2-den.mycricket.com>

(Re: urllib2.URLError: <urlopen error unknown url type: 'http> error using
	twill with python)
 ---------------------------------------------
Sent by a Cricket mobile device
 ---------------------------------------------


From user at example.net  Fri Jul 24 18:58:07 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 00:58:07 +0200
Subject: pack an integer into a string
In-Reply-To: <mailman.3691.1248475441.8015.python-list@python.org>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
	<mailman.3691.1248475441.8015.python-list@python.org>
Message-ID: <4a6a3c82$0$6157$4fafbaef@reader5.news.tin.it>

Sebastian Bassi wrote:
> On Fri, Jul 24, 2009 at 7:28 PM, superpollo<user at example.net> wrote:
> 
>>is there a pythonic and synthetic way (maybe some standard module) to "pack"
>>an integer (maybe a *VERY* big one) into a string? like this:
> 
> 
> What do you mean to pack? Maybe Pickle is what you want.
> 
> import cPickle
> variable = 124348654333577698
> cPickle.dump(variable,open('filename', 'w'))
> 
> To load it:
> 
> import cPickle
> vaariable = cPickle.load(open('filename'))
> 
> It is not "into a string", but instead of a filename, use a string with stringio


  >>> number
  252509952
  >>> f = cStringIO.StringIO()
  >>> cPickle.dump(number , f)
  >>> f.getvalue()
  'I252509952\n.'
  >>>

as you can see, the pickled representation is not what i wanted...

thanks anyway

bye


From piet at cs.uu.nl  Fri Jul 24 19:03:25 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 01:03:25 +0200
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <m23a8lhef6.fsf@cs.uu.nl>

>>>>> superpollo <user at example.net> (s) wrote:

>s> is there a pythonic and synthetic way (maybe some standard module) to
>s> "pack" an integer (maybe a *VERY* big one) into a string? like this:

>>>>> number = 252509952
>>>>> hex(number)
>s>  '0xf0cff00'
>>>>> 

>s> so i would like a string like '\xf0\xcf\xf0\x00'

You have the string wrong.
But the correct one you get with:

In [67]: import struct

In [68]: number = 252509952

In [69]: struct.pack('>I', number)
Out[69]: '\x0f\x0c\xff\x00'

(Please note that this is big endian)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From user at example.net  Fri Jul 24 19:11:08 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 01:11:08 +0200
Subject: pack an integer into a string
In-Reply-To: <4a6a3c82$0$6157$4fafbaef@reader5.news.tin.it>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
	<mailman.3691.1248475441.8015.python-list@python.org>
	<4a6a3c82$0$6157$4fafbaef@reader5.news.tin.it>
Message-ID: <4a6a3f8f$0$6157$4fafbaef@reader5.news.tin.it>

superpollo wrote:
> Sebastian Bassi wrote:
> 
>> On Fri, Jul 24, 2009 at 7:28 PM, superpollo<user at example.net> wrote:
>>
>>> is there a pythonic and synthetic way (maybe some standard module) to 
>>> "pack"
>>> an integer (maybe a *VERY* big one) into a string? like this:
>>
>>
>>
>> What do you mean to pack? Maybe Pickle is what you want.
>>
>> import cPickle
>> variable = 124348654333577698
>> cPickle.dump(variable,open('filename', 'w'))
>>
>> To load it:
>>
>> import cPickle
>> vaariable = cPickle.load(open('filename'))
>>
>> It is not "into a string", but instead of a filename, use a string 
>> with stringio
> 
> 
> 
>  >>> number
>  252509952
>  >>> f = cStringIO.StringIO()
>  >>> cPickle.dump(number , f)
>  >>> f.getvalue()
>  'I252509952\n.'
>  >>>
> 
> as you can see, the pickled representation is not what i wanted...
> 

OTOH, using a higher protocol:

  >>> cPickle.dump(number , f , 1)
  >>> f.getvalue()
  'J\x00\xff\x0c\x0f.'

which is very close to '\xf0\xcf\xf0\x00', that i meant originally... so 
i i change my spec as; '\x0f\x0c\xff\x00' (i.e. left- intead of right- 
zeropadding) i am almost there...

bye


From bartc at freeuk.com  Fri Jul 24 19:15:32 2009
From: bartc at freeuk.com (bartc)
Date: Fri, 24 Jul 2009 23:15:32 GMT
Subject: len() should always return something
In-Reply-To: <mailman.3644.1248417347.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <ogram.60449$OO7.20862@text.news.virginmedia.com>

"Dr. Phillip M. Feldman" <pfeldman at verizon.net> wrote in message 
news:mailman.3644.1248417347.8015.python-list at python.org...
>
> Some aspects of the Python design are remarkably clever, while others 
> leave
> me perplexed. Here's an example of the latter: Why does len() give an 
> error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1.

So you want len() to treat 123 as though it could potentially be a list 
containing a single element?

In that case there could be an ambiguity here:

print len([10,20,30])

Should it print 3 (the elements in [10,20,30]), or 1 (treating [10,20,30] as 
a potential list containing the single element [10,20,30])?

-- 
bartc 



From user at example.net  Fri Jul 24 19:16:07 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 01:16:07 +0200
Subject: pack an integer into a string
In-Reply-To: <m23a8lhef6.fsf@cs.uu.nl>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
	<m23a8lhef6.fsf@cs.uu.nl>
Message-ID: <4a6a40ba$0$6157$4fafbaef@reader5.news.tin.it>

Piet van Oostrum wrote:
...
> You have the string wrong.

oops yea.

> But the correct one you get with:
> 
> In [67]: import struct
> 
> In [68]: number = 252509952
> 
> In [69]: struct.pack('>I', number)
> Out[69]: '\x0f\x0c\xff\x00'
>
> (Please note that this is big endian)

thanks a lot, but it does not work for large integers:

  >>> number
  283691163101781L
  >>> struct.pack('>I', number)
  Traceback (most recent call last):
    File "<stdin>", line 1, in ?
  OverflowError: long int too large to convert
  >>>

bye


From scriptlearner at gmail.com  Fri Jul 24 19:20:00 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Fri, 24 Jul 2009 16:20:00 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
Message-ID: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>

My parent thread keeps a counter for the number of free child workers
(say 100) and initializes some child threads and call child.start().
Once the number of free child workers reach 0, the parent thread will
wait until some at least one child thread finishes and then it will
initialize another child thread.
My question is, how can a child thread notify the parent that it's
done so that the parent can call join() on it?  I am not sure how a
child thread can send a signal to its parent while it may not even
know anything about it's parent.  Can you guys please provide some
suggestions?  Some code samples will be nice.  Thanks.


From greg at cosc.canterbury.ac.nz  Fri Jul 24 19:24:13 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sat, 25 Jul 2009 11:24:13 +1200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
	<861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
Message-ID: <7cuu3eF29jmmuU2@mid.individual.net>

Bearophile wrote:

> Was this link, shown by William, not enough?
> http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1

Yes, sorry, I posted too soon.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Fri Jul 24 19:26:44 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sat, 25 Jul 2009 11:26:44 +1200
Subject: clean way prepend an element to a numpy array
In-Reply-To: <mailman.3554.1248291958.8015.python-list@python.org>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>	<7cnr5tF28183hU1@mid.individual.net>
	<mailman.3554.1248291958.8015.python-list@python.org>
Message-ID: <7cuu86F2945qmU1@mid.individual.net>

Robert Kern wrote:

>> a[:0] = array('i', [0])
> 
> Not when 'a' is a numpy array rather than an array.array.

That's true, but I got the impression that the OP was
talking about array.array, not numpy.array.

It's very confusing having two widely-used types
both called 'array'. :-(

-- 
Greg


From robert.kern at gmail.com  Fri Jul 24 19:35:01 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 24 Jul 2009 18:35:01 -0500
Subject: clean way prepend an element to a numpy array
In-Reply-To: <7cuu86F2945qmU1@mid.individual.net>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>	<7cnr5tF28183hU1@mid.individual.net>	<mailman.3554.1248291958.8015.python-list@python.org>
	<7cuu86F2945qmU1@mid.individual.net>
Message-ID: <h4dgf6$uhe$1@ger.gmane.org>

On 2009-07-24 18:26, greg wrote:
> Robert Kern wrote:
>
>>> a[:0] = array('i', [0])
>>
>> Not when 'a' is a numpy array rather than an array.array.
>
> That's true, but I got the impression that the OP was
> talking about array.array, not numpy.array.

Did you read the Subject: line? :-)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python at mrabarnett.plus.com  Fri Jul 24 19:44:36 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 25 Jul 2009 00:44:36 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
Message-ID: <4A6A4764.1080206@mrabarnett.plus.com>

scriptlearner at gmail.com wrote:
> My parent thread keeps a counter for the number of free child workers
> (say 100) and initializes some child threads and call child.start().
> Once the number of free child workers reach 0, the parent thread will
> wait until some at least one child thread finishes and then it will
> initialize another child thread.
> My question is, how can a child thread notify the parent that it's
> done so that the parent can call join() on it?  I am not sure how a
> child thread can send a signal to its parent while it may not even
> know anything about it's parent.  Can you guys please provide some
> suggestions?  Some code samples will be nice.  Thanks.

I would create a queue ("Queue" module) and pass it to each child; the 
child would put something (eg a reference to itself) in the queue when
it had finished.


From lists at cheimes.de  Fri Jul 24 19:53:19 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sat, 25 Jul 2009 01:53:19 +0200
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
Message-ID: <h4dhhf$1g5$1@ger.gmane.org>

scriptlearner at gmail.com wrote:
> My parent thread keeps a counter for the number of free child workers
> (say 100) and initializes some child threads and call child.start().
> Once the number of free child workers reach 0, the parent thread will
> wait until some at least one child thread finishes and then it will
> initialize another child thread.
> My question is, how can a child thread notify the parent that it's
> done so that the parent can call join() on it?  I am not sure how a
> child thread can send a signal to its parent while it may not even
> know anything about it's parent.  Can you guys please provide some
> suggestions?  Some code samples will be nice.  Thanks.

You are using the wrong approach here. There is a much easier solution
to your problem although it's not obvious in the first place. In this
approach the worker threads don't have to notify the parent thread that
they are ready.

The main thread creates a queue and a bunch of worker threads that are
pulling tasks from the queue. As long as the queue is empty all worker
threads block and do nothing. When a task is put into the queue a random
worker thread acquires the task, does it job and sleeps as soon as its
ready. That way you can reuse a thread over and over again without
creating a new worker threads.

When you need to stop the threads you put a kill object into the queue
that tells the thread to shut down instead of blocking on the queue.

Christian



From python at mrabarnett.plus.com  Fri Jul 24 20:05:22 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 25 Jul 2009 01:05:22 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <h4dhhf$1g5$1@ger.gmane.org>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<h4dhhf$1g5$1@ger.gmane.org>
Message-ID: <4A6A4C42.40004@mrabarnett.plus.com>

Christian Heimes wrote:
> scriptlearner at gmail.com wrote:
>> My parent thread keeps a counter for the number of free child workers
>> (say 100) and initializes some child threads and call child.start().
>> Once the number of free child workers reach 0, the parent thread will
>> wait until some at least one child thread finishes and then it will
>> initialize another child thread.
>> My question is, how can a child thread notify the parent that it's
>> done so that the parent can call join() on it?  I am not sure how a
>> child thread can send a signal to its parent while it may not even
>> know anything about it's parent.  Can you guys please provide some
>> suggestions?  Some code samples will be nice.  Thanks.
> 
> You are using the wrong approach here. There is a much easier solution
> to your problem although it's not obvious in the first place. In this
> approach the worker threads don't have to notify the parent thread that
> they are ready.
> 
> The main thread creates a queue and a bunch of worker threads that are
> pulling tasks from the queue. As long as the queue is empty all worker
> threads block and do nothing. When a task is put into the queue a random
> worker thread acquires the task, does it job and sleeps as soon as its
> ready. That way you can reuse a thread over and over again without
> creating a new worker threads.
> 
> When you need to stop the threads you put a kill object into the queue
> that tells the thread to shut down instead of blocking on the queue.
> 
The extra trick is that when a thread gets the kill object it puts it
back before terminating so that another thread will also get it.


From googler.1.webmaster at spamgourmet.com  Fri Jul 24 20:12:13 2009
From: googler.1.webmaster at spamgourmet.com (moerchendiser2k3)
Date: Fri, 24 Jul 2009 17:12:13 -0700 (PDT)
Subject: Freetype2 in PIL
Message-ID: <95f321b4-d7e8-4515-8743-dad86298024d@a26g2000yqn.googlegroups.com>

Hi,

I have a problem with Freetype2 in the Python Image Library. I
compiled it as 64bit and I got a file named freetype239.lib. So I
added this file to a folder called lib. I added the parent folder of
the lib folder to the setup.py settings (like all the others: libjpeg,
zlib). LIbjpeg and Zlib works fine on Windows 64 bit and the installer
can find them.

But I just get a "Freetype2 not found". Even renaming it to
freetype.lib and freetype2.lib doesnt work.


Any suggestions why PIL cant find the library?

Bye and thanks in advance :)


From googler.1.webmaster at spamgourmet.com  Fri Jul 24 20:12:13 2009
From: googler.1.webmaster at spamgourmet.com (moerchendiser2k3)
Date: Fri, 24 Jul 2009 17:12:13 -0700 (PDT)
Subject: Freetype2 in PIL
Message-ID: <dff064ef-e6e9-46a0-9256-ef887336c246@y19g2000yqy.googlegroups.com>

Hi,

I have a problem with Freetype2 in the Python Image Library. I
compiled it as 64bit and I got a file named freetype239.lib. So I
added this file to a folder called lib. I added the parent folder of
the lib folder to the setup.py settings (like all the others: libjpeg,
zlib). LIbjpeg and Zlib works fine on Windows 64 bit and the installer
can find them.

But I just get a "Freetype2 not found". Even renaming it to
freetype.lib and freetype2.lib doesnt work.


Any suggestions why PIL cant find the library?

Bye and thanks in advance :)


From gallium.arsenide at gmail.com  Fri Jul 24 20:14:59 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Fri, 24 Jul 2009 17:14:59 -0700 (PDT)
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it> 
	<m23a8lhef6.fsf@cs.uu.nl>
	<4a6a40ba$0$6157$4fafbaef@reader5.news.tin.it>
Message-ID: <669833bd-7d70-4cec-a9a3-9de50d77d8e7@c14g2000yqm.googlegroups.com>

On Jul 24, 7:16?pm, superpollo <u... at example.net> wrote:
> thanks a lot, but [struct] does not work for large integers:

Since the struct module is designed specifically for C-style structs,
it's definitely not going to handle arbitrary-length integers on its
own.  You could chop up your Python (long) integer into C-sized pieces
and then pack the pieces; but if you need to do that, the advantage of
using struct at all may be minimal or even completely gone.

> OTOH, using a higher [pickle] protocol:

If you are sure you are going to keep using the same version of
Python, then this could work.  I would personally not depend on this
to keep working in future versions.

I'm not aware of any existing package that does what you want.  Maybe
someone else does.  How I personally would tackle your problem is to
write the whole thing from scratch (as you've done).

John


From deets at nospam.web.de  Fri Jul 24 20:33:11 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 25 Jul 2009 02:33:11 +0200
Subject: cgi.fieldstorage()
In-Reply-To: <f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
	<f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
Message-ID: <7cv268F29q0j5U1@mid.uni-berlin.de>

gert schrieb:
> On Jul 24, 7:32 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> gert schrieb:
>>
>>> this is a non standard way to store multi part post data on disk
>>> def application(environ, response):
>>>     with open('/usr/httpd/var/wsgiTemp','w') as f:
>>>         while True:
>>>             chunk = environ['wsgi.input'].read(8192).decode('latin1')
>>>             if not chunk: break
>>>             f.write(chunk)
>>>     response('200 OK',[])
>>>     return ['complete']
>>> my question is how do i handle the file, so i can shuffle it into a db
>>> using small chunks of memorie ?
>> I don't think that's possible with the current DB-API. There is no
>> stream-based BLOB-interface (as e.g. JDBC offers).
>>
>> So the answer certainly depends on your used RDBMS. For oracle, you
>> would be lucky:
>>
>> http://cx-oracle.sourceforge.net/html/lob.html
>>
>> Other adapters I don't know about.
> 
> sqlite :) ok let say for now it would be impossible on a db level, but
> before i reach the impossible, i still need to parse the file to
> prepare the chunks. How do i do that ? How do i get the chunks without
> loading the hole file into memorie ?

It's memory - memorie might be some nice dutch girl you know :)

Apart from that, your code above does exactly that - reads the data 
chunkwise. If the WSGI-implementation works proper, this will be the 
socket's input stream, so there is no memory overhead involved.

Now of course if you want to have a multi-pass processing of the file 
without putting it into memory, then you need to save it to the harddisk 
befor.

But honestly - we are talking about a web-application here. My 
DSL-connection has 1 MBit upstream, the average server has at least 2GB 
of memory available - so we are talking 20000 seconds uploading time to 
fill that memory. Which is about 5 hours. And you are decoding the data 
to a certain decoding, so we are not talking about binary data here - 
are you really sure memory is an issue?

Diez

Diez


From casevh at gmail.com  Fri Jul 24 20:35:59 2009
From: casevh at gmail.com (casevh)
Date: Fri, 24 Jul 2009 17:35:59 -0700 (PDT)
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <7728c70f-4d1d-4e5c-ae8b-175491fc1d31@f18g2000prf.googlegroups.com>

On Jul 24, 3:28?pm, superpollo <u... at example.net> wrote:
> is there a pythonic and synthetic way (maybe some standard module) to
> "pack" an integer (maybe a *VERY* big one) into a string? like this:
>
> ? >>> number = 252509952
> ? >>> hex(number)
> ? '0xf0cff00'
> ? >>>
>
> so i would like a string like '\xf0\xcf\xf0\x00'
>
> i wrote some code to do it, so ugly i am ashamed to post :-(
>
> i tried xdrlib, but does not quite do what i mean...
>
> bye

This works, I think.

>>> def hex_string(n):
...     a = hex(n)
...     ch_list = []
...     if a.startswith('0x'): a = a[2:]
...     if a.endswith('L'): a = a[:-1]
...     for i in range(0, len(a)):
...         ch_list.append(chr(int(a[i:i+2],16)))
...     return ''.join(ch_list)
...
>>> hex_string(252509952)
'\xf0\x0c\xcf\xff\xf0\x00\x00'
>>> hex_string(283691163101781L)
'\x10\x02 \x03?\xff\xf0\x00\n\xaa\xa5U\x05'
>>>


From deets at nospam.web.de  Fri Jul 24 20:38:28 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 25 Jul 2009 02:38:28 +0200
Subject: Computation/E-mail Expert opinions?
In-Reply-To: <9e520bf6-bc15-4942-a668-d18c2dbaf80f@o32g2000yqm.googlegroups.com>
References: <9e520bf6-bc15-4942-a668-d18c2dbaf80f@o32g2000yqm.googlegroups.com>
Message-ID: <7cv2g5F29q0j5U2@mid.uni-berlin.de>

scribio_vide schrieb:
> MAIL From: <tommyo2 at centrum.sk>
> From: "tommy02" <tommy02 at centrum.sk>
> To: "MeAmI" <MeAmI at vzw.blackberry.net>
> Subject: I AM LOOKING FORWARD TO YOUR ANSWER ON THIS ISSUE
> Date: Fri, 24 Jul 09 11:52:27 Pacific Daylight Time
> MIME-Version: 1.0
> Content-Type: multipart/mixed;boundary= "----
> =_NextPart_000_008C_8F228C8E.684AAFEA"
> X-Priority: 3
> X-MSMail-Priority: Normal
> X-Mailer: Microsoft Outlook Express 6.00.2462.0000
> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2462.0000
> 
> ------=_NextPart_000_008C_8F228C8E.684AAFEA
> Content-Type: text/plain
> Content-Transfer-Encoding: base64
> 

<snip/>

> ZXRtYWlsLmNvbQ0KICAgIA==
> ------=_NextPart_000_008C_8F228C8E.684AAFEA--
> 
> Any ides why I this came to be in my inbox?

It is either an extremely dangerous virus - or an utterly harmless, but 
annoying base64-encoded spam-mail, given the subject.

None of the possibilities justifies a post to *three* newsgroups.

Diez


From scriptlearner at gmail.com  Fri Jul 24 20:39:04 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Fri, 24 Jul 2009 17:39:04 -0700 (PDT)
Subject: time in milliseconds by calling time.time()
Message-ID: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>

I am trying to measure some system response time by using the time.time
() or time.clock() in my script.  However, the numbers I get are in
10s of milliseconds.
For example,
1248481670.34   #from time.time()
0.08                   #from time.clock()

That won't work for me, since the response time may be only a few
milliseconds.
My environment is Solaris 10 with Python 2.4.4 (#7, Feb  9 2007,
22:10:21).

SunOS 5.10 Generic_137112-07 i86pc i386 i86pc


The tricky thing is, if I run the python interpreter and import the
time module, I can get a time floating number in better precision by
calling time.time().  Do you guys have any suggestion on debugging
this problem?  Or, is there any other module I can try?  Thanks.

$ python
Python 2.4.4 (#7, Feb  9 2007, 22:10:21)
[GCC 3.4.6] on sunos5
Type "help", "copyright", "credits" or "license" for more information.
>>> import time
>>> time.time()
1248481930.8023829  <--I like this!
>>> time.clock()
0.0
>>>


From aahz at pythoncraft.com  Fri Jul 24 21:09:08 2009
From: aahz at pythoncraft.com (Aahz)
Date: 24 Jul 2009 18:09:08 -0700
Subject: Python ctypes on win64
References: <f415d834-b2ac-4036-afb1-a12c79480eb4@i6g2000yqj.googlegroups.com>
Message-ID: <h4dlvk$2is$1@panix3.panix.com>

In article <f415d834-b2ac-4036-afb1-a12c79480eb4 at i6g2000yqj.googlegroups.com>,
ulf  <wfluro at gmail.com> wrote:
>
>Does anybody know if python includes a win64 version of ctypes?
>
>According to the documentation it should be included - at least
>there's no special remarks for win64, and I haven't found any recent
>notes saying that it shouldn't work on win64. Yet it looks like both
>the installer from Python.org and from ActiveState.com have disabled
>it.

Nobody seems to have followed up to this, you may have better luck on
the capi-sig mailing list.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From rylesny at gmail.com  Fri Jul 24 21:11:29 2009
From: rylesny at gmail.com (ryles)
Date: Fri, 24 Jul 2009 18:11:29 -0700 (PDT)
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
Message-ID: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>

According to http://www.python.org/doc/essays/packages.html:

"The import statement first tests whether the item is defined in the
package; if not, it assumes it is a module and attempts to load it."

However, I've noticed that once a module is imported using the
`from pkg import mod' syntax, if its name is deleted from the
package namespace then subsequent imports with `from' will fail.

Here is an example of this type of scenario:

$ ls -l pkg
total 8.0K
-rw-rw-r-- 1 ? general   0 Jul 24 20:21 _impl.py
-rw-rw-r-- 1 ? general 147 Jul 24 20:28 __init__.py
-rw-rw-r-- 1 ? general   0 Jul 24 20:33 public2.py
-rw-rw-r-- 1 ? general 208 Jul 24 20:32 public.py

$ cat pkg/__init__.py
from pkg import _impl

# Add functions which refer to objects in _impl
# ...

# Don't "currently" require this in the namespace anymore.
del _impl

$ cat pkg/public.py
# Implement something with the aid of _impl.

from pkg import public2  # OK, fine.
from pkg import _impl    # The module exists, but this will fail.
# Could do import pkg._impl (or a relative import)

$ python
Python 2.6.2 (r262:71600, Jul 16 2009, 14:04:28)
[GCC 4.1.2 20071124 (Red Hat 4.1.2-42)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg import public
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pkg/public.py", line 4, in <module>
    from pkg import _impl    # The module exists, but this will fail.
ImportError: cannot import name _impl
>>> import sys
>>> sys.modules["pkg._impl"]
<module 'pkg._impl' from 'pkg/_impl.py'>
>>> from pkg import _impl
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: cannot import name _impl
>>> import pkg._impl  # Giving up!
>>>

I had previously noted that once a module is imported from a package
it is automatically added to the package namespace:

>>> import pkg
>>> dir(pkg)
['__builtins__', '__doc__', '__file__', '__name__', '__package__',
'__path__']
>>> from pkg import public2
>>> dir(pkg)
['__builtins__', '__doc__', '__file__', '__name__', '__package__',
'__path__', 'public2']
>>>

However, I didn't expect python to give up on importing those names
again
once removed.

Can anyone provide more details on what's occurring here?

Is this behavior intentional (a feature), or, is it in your opinion, a
defect?


From roy at panix.com  Fri Jul 24 21:27:10 2009
From: roy at panix.com (Roy Smith)
Date: Fri, 24 Jul 2009 21:27:10 -0400
Subject: time in milliseconds by calling time.time()
References: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>
Message-ID: <roy-7CF120.21271024072009@news.panix.com>

In article 
<9c600f0c-f4a0-4e8c-bbb9-27f128aecc50 at m7g2000prd.googlegroups.com>,
 "scriptlearner at gmail.com" <scriptlearner at gmail.com> wrote:

> I am trying to measure some system response time by using the time.time
> () or time.clock() in my script.  However, the numbers I get are in
> 10s of milliseconds.
> [...]
> The tricky thing is, if I run the python interpreter and import the
> time module, I can get a time floating number in better precision by
> calling time.time().
> [...]
> >>> time.time()
> 1248481930.8023829  <--I like this!

time.time() is returning a float in either case.  The difference you are 
seeing is purely related to how you are printing it; executing a "print" 
statement as opposed to the interactive interpreter printing a value.

Notice:

Roy-Smiths-MacBook-Pro:play$ python
Python 2.5.1 (r251:54863, Feb  6 2009, 19:02:12) 
[GCC 4.0.1 (Apple Inc. build 5465)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import time
>>> print time.time()
1248484949.75
>>> time.time()
1248484957.151274

and further notice:

>>> x = time.time()
>>> str(x)
'1248485028.58'
>>> repr(x)
'1248485028.5814769'

Keep in mind that while a float may have a large apparent precision, 
there's no promise that the actual value returned by the OS has that much 
precision.  You should be fine if all you're looking for is ms, but I 
wouldn't count on much more than that.


From http  Fri Jul 24 21:30:46 2009
From: http (Paul Rubin)
Date: 24 Jul 2009 18:30:46 -0700
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <7xvdlh8s6x.fsf@ruckus.brouhaha.com>

superpollo <user at example.net> writes:
>   >>> number = 252509952
>   >>> hex(number)
>   '0xf0cff00'
>   >>>
> 
> so i would like a string like '\xf0\xcf\xf0\x00'

def encode(number):
   h = '%x' % number
   if len(h) % 2 == 1:
     h = '0' + h 
   return h.decode('hex')


From pfeldman at verizon.net  Fri Jul 24 22:30:12 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 24 Jul 2009 19:30:12 -0700 (PDT)
Subject: list vs. tuple [Re: len() should always return something]
In-Reply-To: <Xns9C52E231DF188duncanbooth@127.0.0.1>
References: <24639361.post@talk.nabble.com>
	<1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<roy-89AEB3.15032824072009@news.panix.com>
	<Xns9C52E231DF188duncanbooth@127.0.0.1>
Message-ID: <24654347.post@talk.nabble.com>


isinstance(x, (int, float, complex))

is certainly very compact, and does what I want.  Thanks!
-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24654347.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From pfeldman at verizon.net  Fri Jul 24 22:33:30 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 24 Jul 2009 19:33:30 -0700 (PDT)
Subject: len() should always return something
In-Reply-To: <0279f6df$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <24654358.post@talk.nabble.com>


"As far as I know, there is no programming language which treats scalars like
ints as if they were 
vectors of length 1"

Actually, Matlab does:

>> length(5)
ans =
     1
>> 
-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24654358.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From rurpy at yahoo.com  Fri Jul 24 22:41:50 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Fri, 24 Jul 2009 19:41:50 -0700 (PDT)
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
	<zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com> 
	<e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com> 
	<o7Kdncbpm-78SvTXnZ2dnUVZ_vmdnZ2d@pdx.net>
Message-ID: <d273d586-bd4e-4bcc-b6f3-dca969e3bcd7@i6g2000yqj.googlegroups.com>

Scott David Daniels wrote:
> rurpy at yahoo.com wrote:
>> Nick Dumas wrote:
>>> On 7/23/2009 9:23 AM, Mark Lawrence wrote:
>>>> scriptlearner at gmail.com wrote:
>>>>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>>>>> will like to take out the values (valuea, valueb, and valuec).  How do
>>>>> I do that in Python?  The group method will only return the matched
>>>>> part.  Thanks.
>>>>>
>>>>> p = re.compile('#a=*;b=*;c=*;')
>>>>> m = p.match(line)
>>>>>         if m:
>>>>>              print m.group(),
>>>> IMHO a regex for this is overkill, a combination of string methods such
>>>> as split and find should suffice.
>>
>> You're saying that something like the following
>> is better than the simple regex used by the OP?
>> [untested]
>> values = []
>> parts = line.split(';')
>> if len(parts) != 4: raise SomeError()
>> for p, expected in zip (parts[-1], ('#a','b','c')):
>>     name, x, value = p.partition ('=')
>>     if name != expected or x != '=':
>>         raise SomeError()
>>     values.append (value)
>> print values[0], values[1], values[2]
>
> I call straw man: [tested]
>      line = "#a=valuea;b=valueb;c=valuec;"
>      d = dict(single.split('=', 1)
>               for single in line.split(';') if single)
>      d['#a'], d['b'], d['c']
> If you want checking code, add:
>      if len(d) != 3:
>          raise ValueError('Too many keys: %s in %r)' % (
>                               sorted(d), line))

OK, that seems like a good solution.  It certainly
wasn't an obvious solution to me.  I still have no
problem maintaining that

      [tested]
      line = "#a=valuea;b=valueb;c=valuec;"
      m = re.match ('#a=(.*);b=(.*);c=(.*);', line)
      m.groups((1,2,3))
(If you want checking code, nothing else required.)

is still simpler and clearer (with the obvious
caveat that one is familiar with regexes.)

>> Blech, not in my book.  The regex checks the
>> format of the string, extracts the values, and
>> does so very clearly.  Further, it is easily
>> adapted to other similar formats, or evolutionary
>> changes in format.  It is also (once one is
>> familiar with regexes -- a useful skill outside
>> of Python too) easier to get right (at least in
>> a simple case like this.)
> The posted regex doesn't work; this might be homework, so
> I'll not fix the two problems.  The fact that you did not
> see the failure weakens your claim of "does so very clearly."

Fact? Maybe you should have read the whole thread before
spewing claims that I did not see the regex problem.
The fact that you did not bother to weakens any claims
you make in this thread.
(Of course this line of argumentation is stupid anyway --
even had I not noticed the problem, it would say nothing
about the general case.  My advice to you is not to try
to extrapolate when the sample size is one.)


From pfeldman at verizon.net  Fri Jul 24 22:50:54 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 24 Jul 2009 19:50:54 -0700 (PDT)
Subject: len() should always return something
In-Reply-To: <7ct4b8F29mednU1@mid.uni-berlin.de>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
Message-ID: <24654439.post@talk.nabble.com>


Here's a simple-minded example:

def dumbfunc(xs):
   for x in xs:
      print x

This function works fine if xs is a list of floats, but not if it is single
float.  It can be made to work as follows:

def dumbfunc(xs):
   if isinstance(xs,(int,float,complex)): xs= [xs]
   for x in xs:
      print x

Having to put such extra logic into practically every function is one of the
annoying things about Python.

Phillip


Diez B. Roggisch-2 wrote:
> 
> Dr. Phillip M. Feldman schrieb:
>> Some aspects of the Python design are remarkably clever, while others
>> leave
>> me perplexed. Here's an example of the latter: Why does len() give an
>> error
>> when applied to an int or float? len() should always return something; in
>> particular, when applied to a scalar, it should return a value of 1. Of
>> course, I can define my own function like this:
>> 
>> def mylen(x):
>>    if isinstance(x,int) or isinstance(x,float): return 1
>>    return len(x)
>> 
>> But, this shouldn't be necessary.
> 
> Can you show some example of where that is actually making a piece of 
> code more elegant?
> 
> Diez
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24654439.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From clp2 at rebertia.com  Fri Jul 24 23:02:40 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 20:02:40 -0700
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<24654439.post@talk.nabble.com>
Message-ID: <50697b2c0907242002s1772783jed0a4a68177616cf@mail.gmail.com>

On Fri, Jul 24, 2009 at 7:50 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Here's a simple-minded example:
>
> def dumbfunc(xs):
> ? for x in xs:
> ? ? ?print x
>
> This function works fine if xs is a list of floats, but not if it is single
> float. ?It can be made to work as follows:
>
> def dumbfunc(xs):
> ? if isinstance(xs,(int,float,complex)): xs= [xs]
> ? for x in xs:
> ? ? ?print x
>
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

You can easily fix that using decorators:

(disclaimer: untested, except mentally)

#bit of setup; pays off later
def list_or_single(func):
    def wrapper(arg):
        try: iter(arg)
        except TypeError: arg = [arg]
        return func(arg)
    return wrapper

#now just prefix functions with @list_or_single

@list_or_single
def dumbfunc(xs):
    for x in xs:
        print x

Using the extended call syntax as I explained earlier is another option.

Cheers,
Chris
-- 
http://blog.rebertia.com


From davidj411 at gmail.com  Sat Jul 25 00:21:48 2009
From: davidj411 at gmail.com (davidj411)
Date: Fri, 24 Jul 2009 21:21:48 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<h4dhhf$1g5$1@ger.gmane.org>
	<mailman.3696.1248480299.8015.python-list@python.org>
Message-ID: <b2d13375-f653-417d-ae51-dee6f3e3ebad@j32g2000yqh.googlegroups.com>

could i see an example of this maybe?


From pavlovevidence at gmail.com  Sat Jul 25 00:55:26 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 24 Jul 2009 21:55:26 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
Message-ID: <aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>

On Jul 24, 11:06?am, Raffael Cavallaro
<raffaelcavall... at pas.espam.s.il.vous.plait.mac.com> wrote:
> On 2009-07-23 23:51:02 -0400, Carl Banks <pavlovevide... at gmail.com> said:
>
> > On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
> >> fft1976 wrote:
> >>> How do you explain that something as inferior as Python beat Lisp in
> >>> the market place despite starting 40 years later.
>
> >> Probably due to similar reasons that lead php to become remotely relevant
> > .
>
> > Well, the only reason PHP became relevant because it was an
> > easy
>
> ^^^^^^^^
> ^^^^^^^^ (emphasis added)
>
> > to
> > deploy solution in a single application domain, the web, that happened
> > to explode.
>
> i.e., Python "beat" lisp because it is ~70% of lisp in a form that is
> much more palatable to the average programmer, just as php became
> popular because it is powerful enough to do websites and, most
> importantly, apprehensible to mediocre programmers and even some
> non-programmers.

That the two languages made something easier is the beginning and end
of the similarities between them.

PHP made hacking together a security-hole-ridden website easier.
Python made actual programming easier.

PHP became what it is because it rode on the coattails of a technology
that grew in spite of it (kind of like everything Microsoft has
shipped since Windows 3.1).  Python became what it is because it
earned the respect of programmers, who contributed to it and spread
the word about it.  That it is easy to use is only a part of why it
earned that respect.  Two languages could not have come to prominence
by more different means.

I can handle Python being called inferior to Lisp or a language for
stupid people or a single-core-using dinosaur of a language or worse
than Perl.

But please don't put it on the same level as PHP.  Their situations
have almost nothing in common.


Carl Banks


From pavlovevidence at gmail.com  Sat Jul 25 01:44:04 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 24 Jul 2009 22:44:04 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org> 
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
Message-ID: <e7c3b968-f492-46fb-a80a-e118aea9e3f9@v23g2000pro.googlegroups.com>

On Jul 24, 6:57?am, Grant Edwards <invalid at invalid> wrote:
> On 2009-07-24, Dr. Phillip M. Feldman <pfeld... at verizon.net> wrote:
>
>
>
> > Some aspects of the Python design are remarkably clever, while
> > others leave me perplexed. Here's an example of the latter:
> > Why does len() give an error when applied to an int or float?
> > len() should always return something; in particular, when
> > applied to a scalar, it should return a value of 1.
>
> If len(7) returned a value of 1, then wouldn't one expect 7[0]
> to be valid? ?It isn't, so you'd then have to redefine all
> types so that they are sequences that can be indexed. ?Sounds
> like a big mess to me...

You can call the big mess "Matlab".


Carl Banks


From andreengels at gmail.com  Sat Jul 25 01:47:14 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sat, 25 Jul 2009 07:47:14 +0200
Subject: time in milliseconds by calling time.time()
In-Reply-To: <roy-7CF120.21271024072009@news.panix.com>
References: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>
	<roy-7CF120.21271024072009@news.panix.com>
Message-ID: <6faf39c90907242247o4e6d50b6m5871faa7f08b447f@mail.gmail.com>

On Sat, Jul 25, 2009 at 3:27 AM, Roy Smith<roy at panix.com> wrote:

> Keep in mind that while a float may have a large apparent precision,
> there's no promise that the actual value returned by the OS has that much
> precision. ?You should be fine if all you're looking for is ms, but I
> wouldn't count on much more than that.

Even stronger: I wouldn't count on _anything_ more than that. On my
machine, time.time() changes value once per millisecond. I tested this
by looking at a loop that recorded time.time() 100000 times. The total
time in the loop was 61 ms; out of the 100000 numbers, 61 were higher
than the previous one, with the highest difference being 1.00017 ms,
the lowest 0.999928 ms.

-- 
Andr? Engels, andreengels at gmail.com


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 02:18:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 06:18:23 GMT
Subject: time in milliseconds by calling time.time()
References: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>
	<roy-7CF120.21271024072009@news.panix.com>
	<mailman.3701.1248501160.8015.python-list@python.org>
Message-ID: <027a94a5$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 07:47:14 +0200, Andre Engels wrote:

> On Sat, Jul 25, 2009 at 3:27 AM, Roy Smith<roy at panix.com> wrote:
> 
>> Keep in mind that while a float may have a large apparent precision,
>> there's no promise that the actual value returned by the OS has that
>> much precision. ?You should be fine if all you're looking for is ms,
>> but I wouldn't count on much more than that.
> 
> Even stronger: I wouldn't count on _anything_ more than that. On my
> machine, time.time() changes value once per millisecond. I tested this
> by looking at a loop that recorded time.time() 100000 times. The total
> time in the loop was 61 ms; out of the 100000 numbers, 61 were higher
> than the previous one, with the highest difference being 1.00017 ms, the
> lowest 0.999928 ms.



I'm guessing you're running Windows, because for Windows time.time() has 
a low resolution and time.clock() is the higher resolution timer.

I'm running Linux, which is the opposite:


>>> from time import time, clock
>>> def diffs(alist):
...     deltas = []
...     for i in xrange(1, len(alist)):
...             deltas.append( alist[i] - alist[i-1] )
...     return deltas
...
>>> d = [time() for i in xrange(10000)]  # grab raw times
>>> dt = diffs(d)  # calculate the difference between each call
>>> max(dt), min(dt)
(0.00060892105102539062, 1.9073486328125e-06)
>>>
>>> d = [clock() for i in xrange(10000)]  # and again using clock()
>>> dc = diffs(d)
>>> max(dc), min(dc)
(0.010000000000000009, 0.0)

More important than the maximum and minimum time deltas is the resolution 
of ticks in each timer. Under Linux, clock() hardly ever gets updated:

>>> len(dc)  # how many time deltas?
9999
>>> len(filter(None, dc))  # how many non-zero deltas?
2

while time() gets updated frequently:

>>> len(dt)
9999
>>> len(filter(None, dt))
9999



See also the comments in the timeit module.



-- 
Steven


From gagsl-py2 at yahoo.com.ar  Sat Jul 25 02:44:14 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 25 Jul 2009 03:44:14 -0300
Subject: trouble with minidom
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
	<op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>
	<9c8c445f0907241056x11ec5316s2ea6310872cd342@mail.gmail.com>
Message-ID: <op.uxl2b0r0x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 24 Jul 2009 14:56:29 -0300, Ronn Ross <ronn.ross at gmail.com>  
escribi?:
> On Tue, Jul 21, 2009 at 7:32 PM, Gabriel Genellina
> <gagsl-py2 at yahoo.com.ar>wrote:
>> En Tue, 21 Jul 2009 21:08:57 -0300, Ronn Ross <ronn.ross at gmail.com>
>> escribi?:
>>
>>  Hello I'm trying to read an xml file using minidome. The xml looks  
>> like:
>>> <rootNode>
>>>   <project>
>>>      <name>myProj</name>
>>>      <path>/here/</path>
>>>   </project>
>>> </rootNode>
>
> I have used the loop below and it works great, but I need get both child
> elements or 'project' per iteration. I want to build a dictionary that
> resemble this:
> my_dict = {'myProj':'/here/', 'anothername':'anotherpath'}
>
> I couldn't find how to do with in the element tree docs. Can you point  
> me in
> the right direction?

py> import xml.etree.ElementTree as ET
py> xml = """<rootNode>
... <project>
...   <name>myProj</name>
...   <path>/here/</path>
... </project>
... <project>
...   <name>anothername</name>
...   <path>anotherpath</path>
... </project>
... </rootNode>"""
py> doc = ET.fromstring(xml)
py> result = {}
py> for project in doc.findall('project'):
...   name = project.find("name").text
...   path = project.find("path").text
...   result[name] = path
...
py> result
{'anothername': 'anotherpath', 'myProj': '/here/'}

The Element interface is documented here:
http://docs.python.org/library/xml.etree.elementtree.html#the-element-interface
More info in the author's site:
http://www.effbot.org/zone/element-index.htm

(Perhaps you're using Python 2.5? That part of the documentation was  
omited in the 2.5 doc set by mistake. Read the 2.6 docs instead, there was  
no changes)

-- 
Gabriel Genellina



From xahlee at gmail.com  Sat Jul 25 02:54:22 2009
From: xahlee at gmail.com (Xah Lee)
Date: Fri, 24 Jul 2009 23:54:22 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
Message-ID: <aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>

PHP is popular because it is geared for the server-side web scripting
lang, and simpler and easy to use, than popular free alternatives at
the time (such as Perl and Java's JSP).

Python became popular primarily because its ease-to-read syntax.

Btween the two, PHP is much easier to use, and much a pleasure to
program in. Python is a pain in the ass.

PHP is functional. The language is not elegant, lots of
inconsistancies. However, it's a joy to use for any practical task in
its web scripting field. PHP has one of the best documentation among
open source computer languages, i'd say top 5.

Python is a twist, with half-assed lambda, a culty community thinking
"computer science R us", and it has this OOP obsession. The Guido guy
do not understand functional programing, but has the pleasure to
actitively badmouth it.

References:

? Language, Purity, Cult, and Deception
  http://xahlee.org/UnixResource_dir/writ/lang_purity_cult_deception.html

? What Languages to Hate
  http://xahlee.org/UnixResource_dir/writ/language_to_hate.html

? Lambda in Python 3000
  http://xahlee.org/perl-python/python_3000.html

? Python Documentation Problems
  http://xahlee.org/perl-python/python_doc_index.html

? Examples Of Quality Documentation In The Computing Industry
  http://xahlee.org/perl-python/quality_docs.html

? Xah's Perl and Python Tutorial
  http://xahlee.org/perl-python/index.html

? Xah's PHP Tutorial
  http://xahlee.org/php/index.html

  Xah
? http://xahlee.org/

?


From andreengels at gmail.com  Sat Jul 25 02:55:40 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sat, 25 Jul 2009 08:55:40 +0200
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<24654439.post@talk.nabble.com>
Message-ID: <6faf39c90907242355m1de6d4e2s6a575a6c7469b67f@mail.gmail.com>

On Sat, Jul 25, 2009 at 4:50 AM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Here's a simple-minded example:
>
> def dumbfunc(xs):
> ? for x in xs:
> ? ? ?print x
>
> This function works fine if xs is a list of floats, but not if it is single
> float. ?It can be made to work as follows:
>
> def dumbfunc(xs):
> ? if isinstance(xs,(int,float,complex)): xs= [xs]
> ? for x in xs:
> ? ? ?print x
>
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

I don't have this problem - when I have a list of one element, that's
what I use - a list with one element. I think things would get much
simpler if you do such a conversion right at the Matlab-Python
interface, rather than changing all kind of things in Python so that
its types are more matlab-like. Just like you shouldn't program Python
by simply translating Java or C into Python idiom, you also shouldn't
program Python by trying to mimic Matlab. Each language has its own
strengths and weaknesses, and moving things over too much in a
simplistic fashion will usually mean that you get the weaknesses of
both and the strengths of neither.

-- 
Andr? Engels, andreengels at gmail.com


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 03:03:02 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 07:03:02 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
Message-ID: <027a9f1a$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 19:50:54 -0700, Dr. Phillip M. Feldman wrote:

> Here's a simple-minded example:
> 
> def dumbfunc(xs):
>    for x in xs:
>       print x
> 
> This function works fine if xs is a list of floats, but not if it is
> single float.  It can be made to work as follows:
> 
> def dumbfunc(xs):
>    if isinstance(xs,(int,float,complex)):
>       xs= [xs]
>    for x in xs:
>       print x
> 
> Having to put such extra logic into practically every function is one of
> the annoying things about Python.


But it's not "practically every function". It's hardly any function at 
all -- in my code, I don't think I've ever wanted this behavior. I would 
consider it an error for function(42) and function([42]) to behave the 
same way. One is a scalar, and the other is a vector -- they're different 
things, it's poor programming practice to treat them identically.

(If Matlab does this, so much the worse for Matlab, in my opinion.)

However, if you want this behaviour, it's easy enough to get it with a 
decorator:

from functools import wraps
def matlab(func):
    """Decorate func so that it behaves like Matlab, that is, 
    it considers a single scalar argument to be the same as a 
    vector of length one."""
    @wraps(func)
    def inner(arg, **kwargs):
        # If arg is already a vector, don't touch it.
        try:
            # If this succeeds, it's a vector of some type.
            iter(arg)
        except TypeError:
            # It's a scalar.
            arg = [arg]
        # Now call the decorated function (the original).
        return func(arg, **kwargs)
    return inner

With this decorator in hand, you can now easily get the behaviour you 
want with a single extra line per function:

>>> @matlab
... def mean(numbers):
...     return sum(numbers)/len(numbers)
...
>>> mean([4.5])
4.5
>>> mean(4.5)
4.5
>>> mean([4.5, 3.6])
4.0499999999999998


Decorators are extremely powerful constructs, and well worth learning. As 
an example, here's a similar decorator that will accept multiple 
arguments, like the built-in functions min() and max():

def one_or_many(func):
    """Decorate func so that it behaves like the built-ins
    min() and max()."""
    @wraps(func)
    def inner(*args, **kwargs):
        # If we're given a single argument, and it's a vector, 
        # use it as args.
        if len(args) == 1:
            try:
                iter(args[0])
            except TypeError:
                pass
            else:
                # No exception was raised, so it's a vector.
                args = args[0]
        # Now call the decorated function (the original).
        return func(args, **kwargs)
    return inner


And then use it:

>>> @one_or_many
... def minmax(numbers):
...     """Return the minimum and maximum element of numbers, 
...     making a single pass."""
...     # the following will fail if given no arguments
...     smallest = biggest = numbers[0]  
...     for x in numbers[1:]:
...             if x < smallest:
...                     smallest = x
...             elif x > biggest:
...                     biggest = x
...     return (smallest, biggest)
...
>>>
>>> minmax([2, 4, 6, 8, 1, 3, 5, 7])
(1, 8)
>>> minmax(2, 4, 6, 8, 1, 3, 5, 7)
(1, 8)




-- 
Steven


From tayssir.john at googlemail.com  Sat Jul 25 03:23:45 2009
From: tayssir.john at googlemail.com (Tayssir John Gabbour)
Date: Sat, 25 Jul 2009 00:23:45 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<12ce2d31-5028-4b60-a5b1-5d5bf1fc06d7@f20g2000prn.googlegroups.com>
Message-ID: <b85f35ca-f983-4cc3-8763-ee34f825407b@p36g2000prn.googlegroups.com>

On Jul 24, 11:58 pm, ACL <anonymous.c.lis... at gmail.com> wrote:
> I actually think that the thing holding lisp back is 'bus factor'.
>
> Lets assume I have a java project and a lisp project:
>
> Java project:
> I have maybe 10 or 12 people on my team working on various subsystems
> of my project. There are probably one or two 'technical leader' types
> in the group, and a bunch of others who are sort of 'serfs', banging
> out java classes. Lets say one of my important guys gets totally
> splattered by a bus... I've still got another one left! I can rely on
> the other guy to keep things afloat while I train up a new leader
> type.
>
> Lisp project:
> I don't need as many people. I have 3 or 4 people, and one person is
> my technical leader and lisp guru. Guru is probably in charge of more
> difficult macros and (because of that), also in charge of the overall
> design (macros are design patterns embodied in code). Lets say he gets
> totally annihilated by the bus. What do I do now? I had all my eggs in
> one basket and my project is now stalled.

A Clojure programmer mentioned interesting solutions to this used by
his company, such as partnerships with similarly Agile companies.
http://programmingtour.blogspot.com/2009/07/conversation-with-stuart-halloway.html

I agree that the bus factor -- as well as some other problems -- works
against Lisp's acceptance.


All the best,
Tayssir


From pavlovevidence at gmail.com  Sat Jul 25 03:49:12 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 25 Jul 2009 00:49:12 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <e82da500-2015-4a75-b77b-32fc4e731567@a39g2000pre.googlegroups.com>

On Jul 23, 11:35?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> Some aspects of the Python design are remarkably clever, while others leave
> me perplexed. Here's an example of the latter: Why does len() give an error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1. Of
> course, I can define my own function like this:
>
> def mylen(x):
> ? ?if isinstance(x,int) or isinstance(x,float): return 1
> ? ?return len(x)
>
> But, this shouldn't be necessary.

I knew that you were coming from Matlab as soon as I saw the subject
line.

I use both Matlab and Python very often, and I understand the design
decisions behind both (insofar as Matlab can be considered a
"design").

The thing to keep in mind about Python is that it's a general purpose
language, not just for mathematical computation, and there are some
things in Python that are a bit suboptimal for math calculations.
This is one of them: when the types of objects you are dealing with
most often are numbers, then there's not much chance for ambiguity
when treating a scalar as a 1x1 matrix.

However, when doing general purpose programming, you often use lots of
types besides numbers, some of which are containers themselves.  This
creates the possibility of ambiguity and inconsistent behavior.  Let's
consider your example function.

def dumbfunc(xs):
   for x in xs:
      print x

You can use it on an list, like this, and there is no ambiguity:

dumbfunc([1,2,3])

Now suppose Python allowed numbers to be treated as degenerate
sequences of length 1.  Then you could pass a number, and it would
work as you expect:

dumbfunc(1)

However, because Python is general purpose, you might also want to
pass other types around, such as strings.  Say you wanted to print a
list of string, you would do this, and it would work as expected:

dumbfunc(["abc","def","ghi"])

Now, the problem.  In the numbers example, you were able to treat a
single number as a degenerate list, and by our supposition, it
worked.  By analogy, you would expect to be able to do the same with a
list of strings, like this:

dumbfunc("abc")

Whoops: doesn't work.  Instead of printing one string "abc" it prints
three strings, "a", "b", and "c".

By allowing scalar numbers to act as degenerate lists, you've
introduced a very bad inconsistency into the language, you've made it
difficult to learn the language by analogy.

For a general purpose language there is really no second-guessing this
design decision.  It would be unequivocally bad to have atomic types
act like sequences.  The reason it isn't so bad in Matlab is that you
can rely on the elements of an array to be scalar.

Matlab, for its part, does contain some types (cell arrays and
structures) that can contain non-scalars for cases when you want to do
that.  However, you will notice that no scalar will ever be treated as
a degenerate cell array or structure.  Even a poorly designed, ad hoc
language like Matlab won't try to treat scalar numbers as cell arrays,
because ambiguity like I described above will appear.  Nope, it takes
an abomination like Perl to do that.

As for how I would recommend you translate the Matlab function that
rely on this: you need to decide whether that scalar number you are
passing in is REALLY a scalar, or a degenerate vector.  If it's the
latter, just get over it and pass in a single-item list.  I have done
these kinds of conversions myself before, and that's the way to do
it.  Trying to be cute and writing functions that can work with both
types will lead to trouble and inconsistency, especially if you are a
Python newbie.  Just pass in a list if your function expects a list.


Carl Banks


From hendrik at microcorp.co.za  Sat Jul 25 03:50:30 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 09:50:30 +0200
Subject: len() should always return something
In-Reply-To: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
Message-ID: <200907250950.30999.hendrik@microcorp.co.za>


On Friday 24 July 2009 16:45:40 Mark Dickinson wrote:

> On Jul 24, 3:11?pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
>
> wrote:
> > Which doesn't make your point less valid. ?In fact I'd go so
> > far as to argue that what len() gives you is the number of
> > items in a container, so len(7) should return 0.
>
> Nah.  7 contains three bits, so len(7) should *clearly* return 3.

Almost right - however the first seven that you typed was a string
seven and not an int - so the hex is 37 and that takes at least
six bits...

:-)

Now if only someone can figure out a reason why it should
return seven, then it would be perfect!

- Hendrik


From deets at nospam.web.de  Sat Jul 25 03:55:26 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 25 Jul 2009 09:55:26 +0200
Subject: len() should always return something
In-Reply-To: <mailman.3699.1248490256.8015.python-list@python.org>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
Message-ID: <7cvs3fF24hjh7U1@mid.uni-berlin.de>

Dr. Phillip M. Feldman schrieb:
> Here's a simple-minded example:
> 
> def dumbfunc(xs):
>    for x in xs:
>       print x
> 
> This function works fine if xs is a list of floats, but not if it is single
> float.  It can be made to work as follows:
> 
> def dumbfunc(xs):
>    if isinstance(xs,(int,float,complex)): xs= [xs]
>    for x in xs:
>       print x
> 
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

And where comes "len(xs)" into play here? What you want is iteration 
over scalars.

I do think that if you frequently have to write code like that, you are 
writing errorneous code.

But might that as it is, a simple


def iterable(i):
     if isinstance(i, (int, float, complex)):
        return [i]
     return i


is all you need. So you can write


for x in iterable(xs):


wherever you expect values to be either scalar or iterable.

Diez


From piet at cs.uu.nl  Sat Jul 25 04:03:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 10:03:58 +0200
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <m2tz11fatt.fsf@cs.uu.nl>

>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (S) wrote:

>S> Chris, I'm curious why you think that these Zen are relevant to the OP's 
>S> complaint.

>S> Re explicit vs implicit, len(42) is just as explicit as len([42, 23]).

>S> Arguably (I wouldn't argue this, but some people might) ints aren't 
>S> "special enough" to break the rule that len(obj) should always return 
>S> something.

>S> (I don't actually agree, but some people might be able to produce a 
>S> coherent argument why len() should apply equally to all objects.)

>S> Re errors passing silently, the OP doesn't believe that len(42) should be 
>S> an error, so that's not relevant.

>S> And there's nothing ambiguous about len(42).

len(42) should be 7.5 million.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From hendrik at microcorp.co.za  Sat Jul 25 04:10:32 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 10:10:32 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<mailman.3570.1248335976.8015.python-list@python.org>
	<f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
Message-ID: <200907251010.32720.hendrik@microcorp.co.za>

On Friday 24 July 2009 17:07:30 Inky 788 wrote:
> On Jul 23, 3:42?am, Hendrik van Rooyen <hend... at microcorp.co.za>
>
> wrote:
8<------------------------
> > Steven showed why you cannot have a mutable thing
> > as a key in a dict.
> >
> > if you think it is contrived, then please consider how you would
> > keep track of say the colour of a pixel on a screen at position
> > (x,y) - this is about the simplest "natural" tuple format and
> > example.
>
> My guess is that this is probably the way most people do it:
>
> ~~~~
> #!/usr/bin/env python
>
> import sys
> import random
>
> if len( sys.argv ) != 3:
>     print "Please pass exactly 2 ints. Exiting."
>     sys.exit(1)
>
> NUM_COLUMNS = int( sys.argv[1] )
> NUM_ROWS    = int( sys.argv[2] )
>
> print "Making array of %s columns by %s rows." % (NUM_COLUMNS,
> NUM_ROWS)
>
> def rand():
>     return int( 255 * random.random())
>
> def make_a_pixel():
>     #       red     green   blue
>     return [rand(), rand(), rand()]
>
> def make_a_row(num_columns):
>     temp_row = []
>     for i in range(num_columns):
>         temp_row.append( make_a_pixel() )
>     return temp_row
>
> def make_array_of_pixels(num_columns, num_rows):
>     rows = []
>     for i in range(num_rows):
>         rows.append( make_a_row(num_columns) )
>     return rows
>
> def show_pixels(pixel_array):
>     for row in pixel_array:
>         for pixel in row:
>             print pixel, '  ',
>         print
>
>
> rows_of_pixels = make_array_of_pixels(NUM_COLUMNS, NUM_ROWS)
>
> show_pixels(rows_of_pixels)
> ~~~~

Good grief! - Not a dictionary in sight!

I had something in mind where point was an (x,y) tuple,
and point_colours was a dict of possibly named points 
with a list of RGB values. 
(The colour can change, the point is fixed)

If I were doing it your way, I would use the Array module's Array.
But then, strictly speaking it would not be your way any more,
would it?

- Hendrik



From gagsl-py2 at yahoo.com.ar  Sat Jul 25 04:31:20 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 25 Jul 2009 05:31:20 -0300
Subject: How do I generate dia diagrams from python source code?
References: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
Message-ID: <op.uxl7aiixx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 24 Jul 2009 17:52:47 -0300, Qauzzix <qauzzix at gmail.com> escribi?:

> Since I have been using dia to make my UML diagrams. I also found an
> util named dia2code that generates python code from dia diagram. Now
> that I have that option I really want to find a way to generate dia
> diagram from existing code and/or maintain my diagrams.
>
> I have been googling  like crazy trying to find a way but with no
> luck. Anyone here know how to do this?

SPE does that: http://pythonide.stani.be/

-- 
Gabriel Genellina



From hendrik at microcorp.co.za  Sat Jul 25 05:01:46 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 11:01:46 +0200
Subject: len() should always return something
In-Reply-To: <roy-B8E460.15045524072009@news.panix.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
	<roy-B8E460.15045524072009@news.panix.com>
Message-ID: <200907251101.46672.hendrik@microcorp.co.za>

On Friday 24 July 2009 21:04:55 Roy Smith wrote:


> Compressing strings to a single bit is easy.  It's the uncompressing that's
> tricky.

Not really - all you have to do is to apply the EXACT same sequence
of operations that compressed it, in reverse.

The unfortunate part is that this information is in almost all cases
larger than the original, uncompressed string, so that it kind of defeats
the object of compression.

So yes - tricky!

:-)

- Hendrik




From dr.mtarver at ukonline.co.uk  Sat Jul 25 05:30:16 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Sat, 25 Jul 2009 02:30:16 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3636.1248390216.8015.python-list@python.org>
	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>
Message-ID: <948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>

On 24 July, 15:45, nn <prueba... at latinmail.com> wrote:
> On Jul 23, 7:03?pm, Dave Angel <da... at ieee.org> wrote:
>
>
>
>
>
> > Mark Tarver wrote:
> > > I have a very strange error. ?I have two test python files test.py and
> > > python.py which contain the following code
>
> > > #!/usr/bin/python
> > > print "Content-type: text/html"
> > > print
> > > print "<html>"
> > > print "<center>Hello, Linux.com!</center>"
> > > print "</html>"
>
> > > One file (test.py) works; you call it up and it shows a web page with
>
> > > Hello, Linux.com
>
> > > The other fails with a server configuration error. ?Both are running
> > > under Linux, same server, same permissions. ?Running a character scan
> > > shows that both files contain the same printable characters and are
> > > therefore typographically identical. ? They are absolutely the same.
>
> > > The only hint at a difference I can see is that my ftp program says
> > > the files are of unequal lengths. ?test.py is 129 bytes long.
> > > python.py 134 bytes long.
>
> > > A zipped folder containing both files is at
>
> > >www.lambdassociates.org/weird.zip
>
> > > Any ideas welcome.
>
> > > Mark
>
> > Easiest explanation is that python.py has Windows-style newlines. ?In
> > other words, each line ends with 0d0a, rather than the Unix convention
> > of 0a.
>
> > If your server is Unix-based, it can't handle that first line, since it
> > has an illegal character (0d) following the
>
> > #!/usr/bin/python
>
> > line. ?Convert it to Unix line-endings.
>
> > DaveA
>
> Use dos2unix for conversion of the longer file and try again:
>
> http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm- Hide quoted text -
>
> - Show quoted text -

That sounds the ticket - but is there anything that runs under Windows
to do the trick?

Mark


From hendrik at microcorp.co.za  Sat Jul 25 05:34:13 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 11:34:13 +0200
Subject: len() should always return something
In-Reply-To: <h4d4dc$jav$1@adenine.netfront.net>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
Message-ID: <200907251134.13221.hendrik@microcorp.co.za>

On Friday 24 July 2009 22:09:15 Marcus Wanner wrote:

> First one to correctly decompress the value 0 into an ASCII character
> wins the title of the world's most capable hacker :p

that is easy.

the xor of 0 and 1 is 1, which is ASCII soh, if I remember right.

soh is start of header.

Burroughs poll select, anyone?

- Hendrik



From dr.mtarver at ukonline.co.uk  Sat Jul 25 05:46:14 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Sat, 25 Jul 2009 02:46:14 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3636.1248390216.8015.python-list@python.org>
	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>
	<948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>
Message-ID: <0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>

On 25 July, 10:30, Mark Tarver <dr.mtar... at ukonline.co.uk> wrote:
> On 24 July, 15:45, nn <prueba... at latinmail.com> wrote:
>
>
>
>
>
> > On Jul 23, 7:03?pm, Dave Angel <da... at ieee.org> wrote:
>
> > > Mark Tarver wrote:
> > > > I have a very strange error. ?I have two test python files test.py and
> > > > python.py which contain the following code
>
> > > > #!/usr/bin/python
> > > > print "Content-type: text/html"
> > > > print
> > > > print "<html>"
> > > > print "<center>Hello, Linux.com!</center>"
> > > > print "</html>"
>
> > > > One file (test.py) works; you call it up and it shows a web page with
>
> > > > Hello, Linux.com
>
> > > > The other fails with a server configuration error. ?Both are running
> > > > under Linux, same server, same permissions. ?Running a character scan
> > > > shows that both files contain the same printable characters and are
> > > > therefore typographically identical. ? They are absolutely the same.
>
> > > > The only hint at a difference I can see is that my ftp program says
> > > > the files are of unequal lengths. ?test.py is 129 bytes long.
> > > > python.py 134 bytes long.
>
> > > > A zipped folder containing both files is at
>
> > > >www.lambdassociates.org/weird.zip
>
> > > > Any ideas welcome.
>
> > > > Mark
>
> > > Easiest explanation is that python.py has Windows-style newlines. ?In
> > > other words, each line ends with 0d0a, rather than the Unix convention
> > > of 0a.
>
> > > If your server is Unix-based, it can't handle that first line, since it
> > > has an illegal character (0d) following the
>
> > > #!/usr/bin/python
>
> > > line. ?Convert it to Unix line-endings.
>
> > > DaveA
>
> > Use dos2unix for conversion of the longer file and try again:
>
> >http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm-Hide quoted text -
>
> > - Show quoted text -
>
> That sounds the ticket - but is there anything that runs under Windows
> to do the trick?
>
> Mark- Hide quoted text -
>
> - Show quoted text -

OK, got a version

http://www.bastet.com/

has dos2unix.exe for Windows.  And it solves the problem.

Many thanks all for help on this baffling error

Mark


From piet at cs.uu.nl  Sat Jul 25 06:20:37 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 12:20:37 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<mailman.3662.1248445305.8015.python-list@python.org>
	<m23a8mi0m9.fsf@cs.uu.nl>
	<mailman.3673.1248458763.8015.python-list@python.org>
Message-ID: <m2zlatdpxm.fsf@cs.uu.nl>

>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:

>RJ> The point was, and remains, that this newsgroup gets regular traffic
>RJ> from people who expect Python's variables to act like C's variables,
>RJ> demonstrating that describing them as "quite compatible" is somewhat
>RJ> misleading.

So let' study these postings carefully to see what the actual confusion
is. I myself think that the confusion is not so much the variable
concept but the vale vs. reference semantics of objects. As such the
same thing plays a role in Java. Although the binding mechanisms in Java
and Python are different I don't think the actual semantics are so much
difference as to cause much confusion (with C it could be more). But
such a study could reveal that.

BTW. Which postings from (say) the last month did you have in mind?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jon at ffconsultancy.com  Sat Jul 25 07:02:08 2009
From: jon at ffconsultancy.com (Jon Harrop)
Date: Sat, 25 Jul 2009 12:02:08 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<12ce2d31-5028-4b60-a5b1-5d5bf1fc06d7@f20g2000prn.googlegroups.com>
Message-ID: <q8GdnQhErZpFSPfXnZ2dnUVZ8gVi4p2d@brightview.co.uk>

ACL wrote:
> Lisp project:
> I don't need as many people...

Is there any actual evidence of that?

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
http://www.ffconsultancy.com/?u


From piet at cs.uu.nl  Sat Jul 25 07:14:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 13:14:08 +0200
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<h4dhhf$1g5$1@ger.gmane.org>
	<mailman.3696.1248480299.8015.python-list@python.org>
	<b2d13375-f653-417d-ae51-dee6f3e3ebad@j32g2000yqh.googlegroups.com>
Message-ID: <m2vdlhdngf.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:

>d> could i see an example of this maybe?

queue is a shared Queue instance.

The parent puts the work in the queue with queue.put(work_object).
After all work has been put in the queue it puts a sentinel

	queue.put(None)

Each child thread (consumer) has a loop getting things out of the queue:

while True:
	work = queue.get()
	if work is None: break
	#do real stuff using work

queue.put(None) #put back the sentinel for other worker threads.

#finish

(Thanks to Dennis Lee Bieber)

Instead of None you can also create a special sentinel object and use that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From davea at ieee.org  Sat Jul 25 07:18:58 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 25 Jul 2009 07:18:58 -0400
Subject: strange python scripting error
In-Reply-To: <0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>	<mailman.3636.1248390216.8015.python-list@python.org>	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>	<948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>
	<0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>
Message-ID: <4A6AEA22.1030207@ieee.org>

Mark Tarver wrote:
> <snip>
>   
>>
>>> Use dos2unix for conversion of the longer file and try again:
>>>       
>>> http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm-Hide quoted text -
>>>       
>>> - Show quoted text -
>>>       
>> That sounds the ticket - but is there anything that runs under Windows
>> to do the trick?
>>
>> Mark- Hide quoted text -
>>
>> - Show quoted text -
>>     
>
> OK, got a version
>
> http://www.bastet.com/
>
> has dos2unix.exe for Windows.  And it solves the problem.
>
> Many thanks all for help on this baffling error
>
> Mark
>
>   
I use metapad for simple text editing, see    
http://en.wikipedia.org/wiki/Metapad

It's free, loads very quickly, and has a number of features I like.  One 
of its trivial features is to read/write files in four different 
formats.  In the file menu, you just choose what file-format you need now.

Another thing I'd point out is that some ftp programs will do this 
conversion as the file is being sent between a local DOS machine and a 
Unix machine on the internet.


DaveA



From gert.cuykens at gmail.com  Sat Jul 25 07:45:31 2009
From: gert.cuykens at gmail.com (gert)
Date: Sat, 25 Jul 2009 04:45:31 -0700 (PDT)
Subject: cgi.fieldstorage()
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
	<f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
	<7cv268F29q0j5U1@mid.uni-berlin.de>
Message-ID: <13ed9818-aacd-4260-800b-a04177e13681@n11g2000yqb.googlegroups.com>

On Jul 25, 2:33?am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> gert schrieb:
>
> > On Jul 24, 7:32 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> >> gert schrieb:
>
> >>> this is a non standard way to store multi part post data on disk
> >>> def application(environ, response):
> >>> ? ? with open('/usr/httpd/var/wsgiTemp','w') as f:
> >>> ? ? ? ? while True:
> >>> ? ? ? ? ? ? chunk = environ['wsgi.input'].read(8192).decode('latin1')
> >>> ? ? ? ? ? ? if not chunk: break
> >>> ? ? ? ? ? ? f.write(chunk)
> >>> ? ? response('200 OK',[])
> >>> ? ? return ['complete']
> >>> my question is how do i handle the file, so i can shuffle it into a db
> >>> using small chunks of memorie ?
> >> I don't think that's possible with the current DB-API. There is no
> >> stream-based BLOB-interface (as e.g. JDBC offers).
>
> >> So the answer certainly depends on your used RDBMS. For oracle, you
> >> would be lucky:
>
> >>http://cx-oracle.sourceforge.net/html/lob.html
>
> >> Other adapters I don't know about.
>
> > sqlite :) ok let say for now it would be impossible on a db level, but
> > before i reach the impossible, i still need to parse the file to
> > prepare the chunks. How do i do that ? How do i get the chunks without
> > loading the hole file into memorie ?
>
> It's memory - memorie might be some nice dutch girl you know :)
>
> Apart from that, your code above does exactly that - reads the data
> chunkwise. If the WSGI-implementation works proper, this will be the
> socket's input stream, so there is no memory overhead involved.
>
> Now of course if you want to have a multi-pass processing of the file
> without putting it into memory, then you need to save it to the harddisk
> befor.
>
> But honestly - we are talking about a web-application here. My
> DSL-connection has 1 MBit upstream, the average server has at least 2GB
> of memory available - so we are talking 20000 seconds uploading time to
> fill that memory. Which is about 5 hours. And you are decoding the data
> to a certain decoding, so we are not talking about binary data here -
> are you really sure memory is an issue?
>

What about some http upload resume features ?


From pavlovevidence at gmail.com  Sat Jul 25 07:45:48 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 25 Jul 2009 04:45:48 -0700 (PDT)
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net> 
	<8763di5d1d.fsf@benfinney.id.au>
Message-ID: <2977b59f-6843-4c2e-86c2-c0fa5dfdcf72@u38g2000pro.googlegroups.com>

On Jul 24, 8:14?am, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Hrvoje Niksic <hnik... at xemacs.org> writes:
> > The term "variable" is used in the Python language reference and
> > elsewhere
>
> Yes. It should also be abundantly clear from the constant stream of
> confused newbies on this point that its usage of that term is different
> to what many expect from usage elsewhere.

Personally, I haven't noticed a constant stream, just a few here and
there.

I expect that someone used to C variables will expect Python variables
to behave the same way even if you call them something different, so
what really is the point?


Carl Banks


From pavlovevidence at gmail.com  Sat Jul 25 07:49:09 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 25 Jul 2009 04:49:09 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>
Message-ID: <7fa7aa37-fd9e-4702-85f8-1f9b9a05c54d@i18g2000pro.googlegroups.com>

On Jul 24, 11:54?pm, Xah Lee <xah... at gmail.com> wrote:
[snip]
> References:
>
> ? Language, Purity, Cult, and Deception
> ?http://xahlee.org/UnixResource_dir/writ/lang_purity_cult_deception.html
>
> ? What Languages to Hate
> ?http://xahlee.org/UnixResource_dir/writ/language_to_hate.html
>
> ? Lambda in Python 3000
> ?http://xahlee.org/perl-python/python_3000.html
>
> ? Python Documentation Problems
> ?http://xahlee.org/perl-python/python_doc_index.html
>
> ? Examples Of Quality Documentation In The Computing Industry
> ?http://xahlee.org/perl-python/quality_docs.html
>
> ? Xah's Perl and Python Tutorial
> ?http://xahlee.org/perl-python/index.html
>
> ? Xah's PHP Tutorial
> ?http://xahlee.org/php/index.html
>
> ? Xah
> ?http://xahlee.org/

Wow, you leave no stone unturned.


> "computer science R us"

I'm stealing this.


Carl BAnks


From marcusw at cox.net  Sat Jul 25 08:55:47 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 25 Jul 2009 08:55:47 -0400
Subject: len() should always return something
In-Reply-To: <mailman.3708.1248514333.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<roy-B8E460.15045524072009@news.panix.com>	<h4d4dc$jav$1@adenine.netfront.net>
	<mailman.3708.1248514333.8015.python-list@python.org>
Message-ID: <h4evck$r63$1@adenine.netfront.net>

On 7/25/2009 5:34 AM, Hendrik van Rooyen wrote:
> On Friday 24 July 2009 22:09:15 Marcus Wanner wrote:
> 
>> First one to correctly decompress the value 0 into an ASCII character
>> wins the title of the world's most capable hacker :p
> 
> that is easy.
> 
> the xor of 0 and 1 is 1, which is ASCII soh, if I remember right.
> 
> soh is start of header.
> 
> Burroughs poll select, anyone?
> 
> - Hendrik
> 
nope, not soh.

Marcus


From piet at cs.uu.nl  Sat Jul 25 08:57:19 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 14:57:19 +0200
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
References: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>
Message-ID: <m2iqhgex8w.fsf@cs.uu.nl>

>>>>> ryles <rylesny at gmail.com> (r) wrote:

>r> According to http://www.python.org/doc/essays/packages.html:
>r> "The import statement first tests whether the item is defined in the
>r> package; if not, it assumes it is a module and attempts to load it."

>r> However, I've noticed that once a module is imported using the
>r> `from pkg import mod' syntax, if its name is deleted from the
>r> package namespace then subsequent imports with `from' will fail.

This is incorrectly stated. Also on the initial import it will fail, not
just on subsequent imports.

piet$ python
Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39) 
[GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg import _impl
_impl # this is from a print statement in _impl to show that it did import
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: cannot import name _impl
>>> 

According to the documentation
<http://docs.python.org/library/functions.html#__import__> the statement
from pkg import _impl

_temp = __import__('pkg', globals(), locals(), ['_impl'], -1)
_impl = _temp._impl

This fails because _temp (the imported module) doesn't have a binding
for _impl because you deleted it. By the way, if you have a `normal'
package that doesn't do anything with the name _impl, after the import
the pkg module namespace will have got a binding for _impl although it is not
in your code. It will have been put there by the import code.
In the following example pkg2/__init__.py just contains the line 
A = 2

piet$ python
Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39) 
[GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg2 import _impl
_impl
>>> import sys
>>> dir(sys.modules['pkg2'])
['A', '__builtins__', '__doc__', '__file__', '__name__', '__package__', '__path__', '_impl']
>>> 

It is not clear to me, however what the order is of the statements in
__init__.py and the insertion of _impl in the module namespace.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 08:59:43 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 12:59:43 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com> <m2tz11fatt.fsf@cs.uu.nl>
Message-ID: <027af2b3$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 10:03:58 +0200, Piet van Oostrum wrote:

>>S> And there's nothing ambiguous about len(42).
> 
> len(42) should be 7.5 million.

And "I don't understand your reasoning".upper() should be "Millennium 
Hand and Shrimp!".

Every function would be ambiguous if we treat it as returning an 
arbitrary result. But we don't -- semantics do matter. We expect that 
string.upper() should return the string converted to uppercase, and 
that's not ambiguous because we already know what uppercase means. Even 
if somebody didn't know what uppercase meant, they would expect that it 
had a meaning, and it was just a matter of learning what it meant: for 
example, one might take string.upper() as any of:

* convert every letter a..z to A..Z

* convert the first letter of each word to A..Z

* throw away the argument and return the literal "upper"

* count how many characters are in A..Z

and so forth.

These are some of the infinite number of *possible* meanings to 
string.upper(), but only one of them is the *actual* meaning. The method 
isn't ambiguous, because the language designers have chosen one meaning, 
and having learned what that meaning is, it's the *only* meaning you can 
legitimately use. If you (generic you) are uncertain what that meaning 
is, that's uncertainty, not ambiguity.

Similarly, we might be uncertain about the meaning of len(42) -- 
reasonable values it might return are 0, 1, 2, the number of bits in 42, 
and possibly even 7.5 million as you suggest. But that's our ignorance, 
due to the fact that we haven't yet agreed on a meaning to len(42), and 
not ambiguity: having made up our mind what len(42) should mean, it could 
only mean one thing.

However, mixed string/integer addition is a good example of ambiguity. We 
can add strings:

"1" + "2" => "12"

and we can add integers:

1 + 2 => 3

but it is ambiguous as to what "1" + 2 should return. Guido might have 
made Python behave like Perl, and define addition of a string and an int, 
but there would still be ambiguity in the expression, because we can't 
tell if the coder intended "1"+"2" and forgot to quote the two, or 
intended 1+2 and forgot to convert the string "1" to an int.

Ambiguity essentially boils down to being unable to reasonably predict 
the expectation of the coder. I say "reasonably", because if you allow 
unreasonable situations, everything is "ambiguous":

I typed:

    x = 42 + y

but maybe I intended to import the math module, therefore the + operator 
is ambiguous. Reasonable? No, because we're allowed to assume the coder 
is rational, and mistakes are small.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 09:37:51 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 13:37:51 GMT
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
	<8763di5d1d.fsf@benfinney.id.au>
	<2977b59f-6843-4c2e-86c2-c0fa5dfdcf72@u38g2000pro.googlegroups.com>
Message-ID: <027afba2$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 04:45:48 -0700, Carl Banks wrote:

> On Jul 24, 8:14?am, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
>> Hrvoje Niksic <hnik... at xemacs.org> writes:
>> > The term "variable" is used in the Python language reference and
>> > elsewhere
>>
>> Yes. It should also be abundantly clear from the constant stream of
>> confused newbies on this point that its usage of that term is different
>> to what many expect from usage elsewhere.
> 
> Personally, I haven't noticed a constant stream, just a few here and
> there.
> 
> I expect that someone used to C variables will expect Python variables
> to behave the same way even if you call them something different, so
> what really is the point?

>From time to time we get newbies to Python assuming that len(list) is 
O(N), because the lists they learned about in Comp Sci 101 (or Lisp) are 
linked lists and traversing a linked list to count the items is O(N). Do 
you believe that if Python lists were called "arrays", or "waskilators", 
they would make the same mistake?

[Generalisation] 
C programmers have a mental model for how "variables" behave. They have 
no such mental model for how "objects bound to names" behave, and so they 
are less likely to jump to conclusions about the behaviour of name-
bindings. So I think you are mostly wrong.

However, only mostly -- human beings are generalisers par excellence, or 
rather, *over*-generalisers par excellence. Experienced coders are likely 
to rapidly realise that name-binding is very similar to the C variable 
model, and some percentage of them will over-generalise to assume that 
name-binding is the same as the C model. But if they do, at least that 
will be their fault for jumping to conclusions, not our fault for 
misleading them.


-- 
Steven


From piet at cs.uu.nl  Sat Jul 25 10:08:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 16:08:27 +0200
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<m2tz11fatt.fsf@cs.uu.nl>
	<027af2b3$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <m2eis4etyb.fsf@cs.uu.nl>

>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:

>SD> Ambiguity essentially boils down to being unable to reasonably predict 
>SD> the expectation of the coder. I say "reasonably", because if you allow 
>SD> unreasonable situations, everything is "ambiguous":

That's for me the reason that len(42) is ambiguous. The OP apparently
had 1 as expectation, whereas my first thought was the minimal number of
bits to represent the number and 7.5 million came later :=). The number
of bits I certainly find reasonable, and I would find the number of
decimal digits equally reasonable. More so than 1, actually. 1 as the
length of an int doesn't give any information.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Sat Jul 25 10:33:52 2009
From: aahz at pythoncraft.com (Aahz)
Date: 25 Jul 2009 07:33:52 -0700
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com>
	<h48lvm$qau$1@panix3.panix.com>
	<20efdb6a-c1a5-47dc-8546-7c4ae548e22d@g1g2000pra.googlegroups.com>
Message-ID: <h4f54g$2j9$1@panix3.panix.com>

In article <20efdb6a-c1a5-47dc-8546-7c4ae548e22d at g1g2000pra.googlegroups.com>,
Carl Banks  <pavlovevidence at gmail.com> wrote:
>On Jul 22, 8:38=A0pm, a... at pythoncraft.com (Aahz) wrote:
>> In article <f3d88edf-b5d3-43e4-89a3-b05ef0f55... at p28g2000vbn.googlegroups=
>.com>,
>> Carl Banks =A0<pavlovevide... at gmail.com> wrote:
>>>
>>>You have to be REALLY REALLY careful not to pass any user-supplied
>>>data to it if this is a server running on your computer, of course.
>>
>> Unless, of course, your users are paying for this service.
>
>Well, yes, but I assume that by the time you're deliberately letting
>users pay to run their programs on your server, you will already have
>deployed a full-blown, multi-tiered security strategy that includes
>validation by the server process.  That was sort of beyond the scope
>of the OP's question.

That's not necessarily a good assumption.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From aahz at pythoncraft.com  Sat Jul 25 11:20:51 2009
From: aahz at pythoncraft.com (Aahz)
Date: 25 Jul 2009 08:20:51 -0700
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
Message-ID: <h4f7sj$s6$1@panix3.panix.com>

In article <37da38d2-09a8-4fd2-94b4-5feae9675dcd at k1g2000yqf.googlegroups.com>,
Filip  <pinkeen at gmail.com> wrote:
>
>I tried to fix that with BeautifulSoup + regexp filtering of some
>particular cases I encountered. That was slow and after running my
>data scraper for some time a lot of new problems (exceptions from
>xpath parser) were showing up. Not to mention that BeautifulSoup
>stripped almost all of the content from some heavily broken pages
>(50+KiB page stripped down to some few hundred bytes). Character
>encoding conversion was a hell too - even UTF-8 pages had some non-
>standard characters causing issues.

Have you tried lxml?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From aahz at pythoncraft.com  Sat Jul 25 12:12:49 2009
From: aahz at pythoncraft.com (Aahz)
Date: 25 Jul 2009 09:12:49 -0700
Subject: strange error when trying to log something
References: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>
	<h49ah5$hv3$02$1@news.t-online.com>
Message-ID: <h4fau1$gvn$1@panix3.panix.com>

In article <h49ah5$hv3$02$1 at news.t-online.com>,
Peter Otten  <__peter__ at web.de> wrote:
>
>I have a hunch that you are triggering a reload() somewhere. Example:
>
>Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
>[GCC 4.3.3] on linux2
>Type "help", "copyright", "credits" or "license" for more information.
>>>> import weakref
>>>> weakref.WeakValueDictionary()
><WeakValueDictionary at 140598938447312>
>>>> import UserDict
>>>> reload(UserDict)
><module 'UserDict' from '/usr/lib/python2.6/UserDict.pyc'>
>>>> weakref.WeakValueDictionary()
>Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "/usr/lib/python2.6/weakref.py", line 51, in __init__
>    UserDict.UserDict.__init__(self, *args, **kw)
>TypeError: unbound method __init__() must be called with UserDict instance 
>as first argument (got WeakValueDictionary instance instead)

Nice sleuthing!  How did you figure that out?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From hendrik at microcorp.co.za  Sat Jul 25 12:15:37 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 18:15:37 +0200
Subject: len() should always return something
In-Reply-To: <027af2b3$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com> <m2tz11fatt.fsf@cs.uu.nl>
	<027af2b3$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <200907251815.37762.hendrik@microcorp.co.za>

On Saturday 25 July 2009 14:59:43 Steven D'Aprano wrote:
> On Sat, 25 Jul 2009 10:03:58 +0200, Piet van Oostrum wrote:
> >>S> And there's nothing ambiguous about len(42).
> >
> > len(42) should be 7.5 million.
>
> And "I don't understand your reasoning".upper() should be "Millennium
> Hand and Shrimp!".

That does it.
I will be kinder to you in future.
Anybody who quotes foul old Ron cannot be all bad.

- Hendrik



From albert at spenarnc.xs4all.nl  Sat Jul 25 13:27:52 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 25 Jul 2009 17:27:52 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
Message-ID: <knclug.j10@spenarnc.xs4all.nl>

In article <mailman.3164.1247670958.8015.python-list at python.org>,
Jean-Michel Pichavant  <jeanmichel at sequans.com> wrote:
>Christian Heimes wrote:
>> Chris Rebert wrote:
>>
>>> Using the xor bitwise operator is also an option:
>>> bool(x) ^ bool(y)
>>>
>>
>> I prefer something like:
>>
>>     bool(a) + bool(b) == 1
>>
>> It works even for multiple tests (super xor):
>>
>>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>>       raise ValueError("Exactly one of a, b, c and d must be true")
>>
>> Christian
>>
>>
>While everyone's trying to tell the OP how to workaround the missing xor
>operator, nobody answered the question "why is there no xor operator ?".
>
>If the question was "Why is there no 'or' operator ?", would "because A
>or B <=> not(not A and not B)" be a proper answer ?

No. I think it is because and/or can be extended to be sensible
in a context where objects can be used. (What others have expressed
as having short-circuit evaluation. So sce indeed is the underlying
reason that and/or can be extended sensibly to objects.)

Remains whether we need an xor that only works and requires that
both operands are booleans. That one we have already!
It is called != .

(a!=b)!=c
and
a!=(b!=c)

are the same for booleans, so can indeed be expressed
a!=b!=c   (associativy of xor)

>
>JM
>
Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From tjreedy at udel.edu  Sat Jul 25 13:30:54 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 25 Jul 2009 13:30:54 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <knclug.j10@spenarnc.xs4all.nl>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>
	<knclug.j10@spenarnc.xs4all.nl>
Message-ID: <h4ffge$44n$1@ger.gmane.org>

Albert van der Horst wrote:

> Remains whether we need an xor that only works and requires that
> both operands are booleans. That one we have already!
> It is called != .
> 
> (a!=b)!=c
> and
> a!=(b!=c)
> 
> are the same for booleans, so can indeed be expressed
> a!=b!=c   (associativy of xor)

Not in Python

 >>> a,b,c = True, False, True
 >>> (a!=b)!=c
False
 >>> a!=(b!=c)
False
 >>> a!=b!=c
True
 >>> (a!=b) and (b!=c)
True

In Math and Python, a<b<c means a<b and b<c, not (a<b)<c or a<(b<c).
!= is a comparison operator like <, not an arithmetic operator like + 
(or logical xor). If one has 0/1 or True/False values, we have 
arithmetic xor already, ^, which works as expected.

 >>> (a^b)^c
False
 >>> a^b^c
False

Terry Jan Reedy



From scriptlearner at gmail.com  Sat Jul 25 13:32:06 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Sat, 25 Jul 2009 10:32:06 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
Message-ID: <923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>

First of all, let me say thank you to all of you.  I have asked many
questions (some of them are dump questions), and you have kindly
helped me.  I am not going to reply every message to say thank-you
since that would be annoying for such group with such high daily
traffics.  Thank you very much.

Let's get back to topic of this message.
Here's how I have implemented it so far, and I am taking the queue of
work load items approach.
In my child thread, I will keep checking for available work load item
until a duration is reached.
#inside the child#
        while endTime > time.time():
            try:
                 item = self.q.get(True, 3)
            except Queue.Empty:  #what's wrong?  AttributeError: class
Queue has no attribute 'Empty'
                 print 'cant find any work load item, so lets wait and
try again later'
                 time.sleep(1) #wait and then check again
                 continue
            except:
                 print "Unexpected error:", sys.exc_info()[0]
                 raise
            #do the real work with load item

In my parent thread, I will initialize X (depending on a cfg file)
child threads and keep adding load items to a shared q until the
duration is reached.
#inside the parent#
        callCounter = 0
        workers = [] #a list of child threads
        totalWorkers = 250
        endTime = time.time() + duration
        for i in range(totalWorkers):
            w = Worker(q, duration, i)
            w.start() #worker, do your job now!
            workers.append(w)

        while endTime > time.time():
            time.sleep(1)
                q.put(getWorkloadItem()) #add workload itmes
                callCounter += 1 #actually can we guarantee that the
call will be sent??
                                 #should we ask each child to report
the number of calls they make?

        for i in range(totalWorkers):
            workers[i].join()    # Wait for the child threads to
finish


Overall, it seems to be working now.  Though, I still have a couple of
problems to resolve.
1. I got the following error for the codes that attempt to catch Empty
Queue exception.  What's the right way to use it?
    except Queue.Empty:
AttributeError: class Queue has no attribute 'Empty'

2. What's the best way to have each child thread to report the number
of requests they send when they are done?  To add the numbers to
another queue?

3. I will need to do some logging for response time as well as some
response contents.  I have two choices, one big log file for all
threads (both child and parent), and one log file for each thread.
Given the fact that I may have to log tons of data, I think opening
and maintaining a bunch of smaller logs may be better than dealing
with a big one (it may grow very fast).  Is there any best prastice
for logging in Python?  If I change my mind and go with one big log
file (pass it to each thread), is there anything I should be aware of
for multi-thread access (writting) to the same log file?

Again, thank you.


From albert at spenarnc.xs4all.nl  Sat Jul 25 14:01:33 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 25 Jul 2009 18:01:33 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
	<02746997$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3457.1248158525.8015.python-list@python.org>
Message-ID: <kncnel.g2y@spenarnc.xs4all.nl>

In article <mailman.3457.1248158525.8015.python-list at python.org>,
Jack Diederich  <jackdied at gmail.com> wrote:
>On Mon, Jul 20, 2009 at 10:00 AM, Steven
>D'Aprano<steve at remove-this-cybersource.com.au> wrote:
>> On Mon, 20 Jul 2009 09:34:24 +0000, Sion Arrowsmith wrote:
>>
>>> Terry Reedy =A0<tjreedy at udel.edu> wrote:
>>>>Sion Arrowsmith wrote:
>>>>> Jack Diederich =A0<jackdied at gmail.com> wrote:
>>>>>> It isn't an OrderedDict thing, it is a comparison thing. =A0Two regul=
>ar
>>>>>> dicts also raise an error if you try to LT them.
>>>>> Python 2.5.2
>>>>>>>> d1 =3D dict((str(i), i) for i in range (10)) d2 =3D dict((str(i), i=
>)
>>>>>>>> for i in range (20)) d1 < d2
>>>>> True
>>>>Try reversing the definitions of d1 and d2. The dicts are probably being
>>>>compared by id (address), which is the 2.x CPython default.
>>>
>>> Like this?
>>>
>>>>>> d1 =3D dict((str(i), i) for i in range (20))
>>>>>> d2 =3D dict((str(i), i) for i in range (10))
>>>>>> d1 < d2
>>> False
>>>>>> id(d1) < id(d2)
>>> True
>>>
>>> I didn't know that comparison for anything other than equality defaulted
>>> to using id. That really is rather broken, and I'm glad 3.0 fixed it.
>>
>>
>> I don't think comparisons other than equality use id. That would be
>> rather insane. If anyone can demonstrate such comparisons in a built-in
>> or standard library class, I'd like to see it.
>>
>>
>> For the record, dicts have been comparable with < and > since at least
>> Python 1.5:
>>
>> $ python1.5
>> Python 1.5.2 (#1, Apr =A01 2009, 22:55:54) =A0[GCC 4.1.2 20070925 (Red Ha=
>t
>> 4.1.2-27)] on linux2
>> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>>>
>>>>> {1: 'a', 2: 'b'} < {2: 'b', 3: 'a'}
>> 1
>>
>>
>> Reading the docs:
>>
>> http://docs.python.org/library/stdtypes.html#comparisons
>> http://docs.python.org/library/stdtypes.html#mapping-types-dict
>>
>> I can only suggest that dicts compare in an arbitrary but consistent
>> fashion.
>
>I should have specified 3.x but since we were talking about
>OrderedDicts (only in 3.1) I didn't say it explicitly.   Earlier
>versions of python were very permissive with comparisons -- it was
>rare that any cmp() raised an error and the ultimate fallback was on
>the object's id.  This is one of the non-backwards compatible changes
>in 3k.  Now comparing two of the same thing that don't have an obvious
>ordering is an error.  Is a dict "greater than" if it has a larger
>size?  if its max key is larger?  what does "max key" mean when the
>keys aren't even comparable?.  Comparing things that aren't extremely
>similar is an error now also.

With regard to < and > you are right.
But I think there is a sensible == w.r.t. dict's.
It is to mean that for each key   dict1(key) == dict2(key)
(implying that their key set must be the same)

[I could have used that for one of the euler problems.
You have a 4 by 4 field containing a red or blue square.
That is naturally a mapping of (1,1) ..(4,4) tuples to one
of the objects `blue' `red'. After moving a square you
want to know whether this is a map you already have encountered.]

>
>-Jack


--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From kawenks at gmail.com  Sat Jul 25 14:04:45 2009
From: kawenks at gmail.com (allan)
Date: Sat, 25 Jul 2009 11:04:45 -0700 (PDT)
Subject: Form/Template Fill-in the blanks
Message-ID: <4b77a992-370d-4879-88a0-fdd6a23f7c5d@p10g2000prm.googlegroups.com>

I'm attempting to create a generic python script that will take an EDI
document specification and a database of transactions and be able to
generate a raw EDI file (ansi X12).

I'm looking for ideas on how best to use the strengths of Python to
implement this. I've initially tackled the EDI 812 specifications and
narrowed this down to a specific implementation by a company. This
narrowed down version is what I want to achieve for output. But I want
the script to be generic enough such that I can plug-in another EDI
specification + a database transaction set and it will output the
proper raw file accordingly.

My initial thought was to use:
1. .ini files to declare the EDI configuration
2. Use SQLAlchemy as ORB to simplify access to database objects.

INI file configuration:
* A "root" INI file indicates other INI files that define each segment
of the EDI document.
* Each segment INI defines the data elements of each segment and the
behavior of the segment (one instance or multiple-instance as in a
loop, sequence order, segment code, etc.)
* Specify data elements as either constant, system function (like
datetime), database field or object method (object being the
segment's)
* Load all the ini configuration into a "template" object. Each
segment ini maps to its own segment object.

DB using SQLAlchemy
Gather a Trading Partner data and Credit Transaction (EDI 812
remember?) into one dictionary object
Gather Credit Transaction details into another dictionary object where
it can generate the multiple instance segments

The heart of the matter is how to fuse together the template and the
data from the dictionary objects efficiently. It should be generic
enough to take another set of data dictionary and another template to
generate a completely new EDI document.

I'm stuck at this fusing together thing. Is this a good approach? Is
there an easier to implement approach?

Comments, suggestions, questions please.

Allan


From piet at cs.uu.nl  Sat Jul 25 14:18:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 20:18:46 +0200
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
	<02746997$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3457.1248158525.8015.python-list@python.org>
	<kncnel.g2y@spenarnc.xs4all.nl>
Message-ID: <m2y6qcd3sp.fsf@cs.uu.nl>

>>>>> Albert van der Horst <albert at spenarnc.xs4all.nl> (AvdH) wrote:

>AvdH> With regard to < and > you are right.
>AvdH> But I think there is a sensible == w.r.t. dict's.
>AvdH> It is to mean that for each key   dict1(key) == dict2(key)
>AvdH> (implying that their key set must be the same)

>AvdH> [I could have used that for one of the euler problems.
>AvdH> You have a 4 by 4 field containing a red or blue square.
>AvdH> That is naturally a mapping of (1,1) ..(4,4) tuples to one
>AvdH> of the objects `blue' `red'. After moving a square you
>AvdH> want to know whether this is a map you already have encountered.]

So what's the problem?

piet$ python3
Python 3.1 (r31:73578, Jun 27 2009, 21:49:46) 
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from collections import OrderedDict
>>> a = OrderedDict()
>>> b = OrderedDict()
>>> a[1]=2
>>> b[1]=2
>>> a[3]=4
>>> b[3]=4
>>> a==b
True
>>> b[5]=6
>>> a==b
False
>>> d1 = dict((str(i), i) for i in range (10))
>>> d2 = dict((str(i), i) for i in range (10))
>>> d1 == d2
True

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From constant.beta at gmail.com  Sat Jul 25 14:30:54 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Sat, 25 Jul 2009 11:30:54 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
Message-ID: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>

Hi,

Is there a way to tell if a generator has been exhausted using pure
Python code? I've looked at CPython sources and it seems that
something like "active"/"exhausted" attribute on genobject is missing
from the API. For the time being I am using a simple C extension to
look at f_stacktop pointer of the generator frame, which seems to
differentiate active generators from exhausted ones. See
http://bazaar.launchpad.net/~ruby/pythoscope/support-python2.3/annotate/286/pythoscope/_util.c#L16
for complete source code.

I may be missing something obvious here. Is there a better way to tell
if a given generator object is still active or not?

Cheers,
mk


From python at mrabarnett.plus.com  Sat Jul 25 14:39:24 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 25 Jul 2009 19:39:24 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
Message-ID: <4A6B515C.9040803@mrabarnett.plus.com>

scriptlearner at gmail.com wrote:
> First of all, let me say thank you to all of you.  I have asked many
> questions (some of them are dump questions), and you have kindly
> helped me.  I am not going to reply every message to say thank-you
> since that would be annoying for such group with such high daily
> traffics.  Thank you very much.
> 
> Let's get back to topic of this message.
> Here's how I have implemented it so far, and I am taking the queue of
> work load items approach.
> In my child thread, I will keep checking for available work load item
> until a duration is reached.
> #inside the child#
>         while endTime > time.time():
>             try:
>                  item = self.q.get(True, 3)
>             except Queue.Empty:  #what's wrong?  AttributeError: class
> Queue has no attribute 'Empty'
>                  print 'cant find any work load item, so lets wait and
> try again later'
>                  time.sleep(1) #wait and then check again
>                  continue
>             except:
>                  print "Unexpected error:", sys.exc_info()[0]
>                  raise
>             #do the real work with load item
> 
> In my parent thread, I will initialize X (depending on a cfg file)
> child threads and keep adding load items to a shared q until the
> duration is reached.
> #inside the parent#
>         callCounter = 0
>         workers = [] #a list of child threads
>         totalWorkers = 250
>         endTime = time.time() + duration
>         for i in range(totalWorkers):
>             w = Worker(q, duration, i)
>             w.start() #worker, do your job now!
>             workers.append(w)
> 
>         while endTime > time.time():
>             time.sleep(1)
>                 q.put(getWorkloadItem()) #add workload itmes
>                 callCounter += 1 #actually can we guarantee that the
> call will be sent??
>                                  #should we ask each child to report
> the number of calls they make?
> 
>         for i in range(totalWorkers):
>             workers[i].join()    # Wait for the child threads to
> finish
> 
> 
> Overall, it seems to be working now.  Though, I still have a couple of
> problems to resolve.
> 1. I got the following error for the codes that attempt to catch Empty
> Queue exception.  What's the right way to use it?
>     except Queue.Empty:
> AttributeError: class Queue has no attribute 'Empty'
> 

The exception 'Empty' belongs to the module, not the class. Try
importing as:

     from Queue import Queue, Empty

> 2. What's the best way to have each child thread to report the number
> of requests they send when they are done?  To add the numbers to
> another queue?
> 
Why not? :-)

> 3. I will need to do some logging for response time as well as some
> response contents.  I have two choices, one big log file for all
> threads (both child and parent), and one log file for each thread.
> Given the fact that I may have to log tons of data, I think opening
> and maintaining a bunch of smaller logs may be better than dealing
> with a big one (it may grow very fast).  Is there any best prastice
> for logging in Python?  If I change my mind and go with one big log
> file (pass it to each thread), is there anything I should be aware of
> for multi-thread access (writting) to the same log file?
> 
> Again, thank you.

If you like threads then you could put the log items into a queue and
have another thread writing them to the logfile. :-)

BTW, do you really need 250 threads? Seems like a lot.

I notice that you stop putting items into the queue when endTime is
reached and also the threads terminate when endTime is reached. If items
are put into the queue faster than they're taken out (or an item is put
in just before endTime) then there might still be unprocessed items in
the queue at endTime.


From rknop at pobox.com  Sat Jul 25 14:57:55 2009
From: rknop at pobox.com (Rob Knop)
Date: Sat, 25 Jul 2009 13:57:55 -0500
Subject: RSA cryptography between Python and Java
Message-ID: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>


I've created an RSA key in Java.  I have exported the public key by
making it into a X509EncodedKeySpec and spitting out the result of
getEncoded().

I want to use this public key to encode something in python that I will
send to Java, and then decode in Java with the corresponding private
key.

Are there any python libraries that will take a public key in this
format and do RSA encoding on it?

-- 
--Rob Knop
  E-mail:    rknop at pobox.com
  Home Page: http://www.pobox.com/~rknop/
  Blog:      http://www.sonic.net/~rknop/blog/


From http  Sat Jul 25 15:01:07 2009
From: http (Paul Rubin)
Date: 25 Jul 2009 12:01:07 -0700
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
Message-ID: <7xocr8si30.fsf@ruckus.brouhaha.com>

Rob Knop <rknop at pobox.com> writes:
> Are there any python libraries that will take a public key in this
> format and do RSA encoding on it?

Try www.trevp.com/tlslite


From rylesny at gmail.com  Sat Jul 25 15:11:23 2009
From: rylesny at gmail.com (ryles)
Date: Sat, 25 Jul 2009 12:11:23 -0700 (PDT)
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
References: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>
	<m2iqhgex8w.fsf@cs.uu.nl>
Message-ID: <ef5b3dbe-92ab-45cb-a150-f8a921b68c71@r24g2000vbn.googlegroups.com>

On Jul 25, 8:57?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> ryles <ryle... at gmail.com> (r) wrote:
> >r> According tohttp://www.python.org/doc/essays/packages.html:
> >r> "The import statement first tests whether the item is defined in the
> >r> package; if not, it assumes it is a module and attempts to load it."
> >r> However, I've noticed that once a module is imported using the
> >r> `from pkg import mod' syntax, if its name is deleted from the
> >r> package namespace then subsequent imports with `from' will fail.
>
> This is incorrectly stated. Also on the initial import it will fail, not
> just on subsequent imports.
>
> piet$ python
> Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39)
> [GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
> Type "help", "copyright", "credits" or "license" for more information.>>> from pkg import _impl
>
> _impl # this is from a print statement in _impl to show that it did import
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> ImportError: cannot import name _impl
>

Well, since __init__.py is executed first, I would regard it as
causing the initial (successful) import, and yours being the
subsequent one, so that the "initial" import does not fail, the
subsequent one does. Wording aside, though, I think we are on the same
page here.

>
> According to the documentation
> <http://docs.python.org/library/functions.html#__import__> the statement
> from pkg import _impl
>
> _temp = __import__('pkg', globals(), locals(), ['_impl'], -1)
> _impl = _temp._impl
>
> This fails because _temp (the imported module) doesn't have a binding
> for _impl because you deleted it.

But supposing we hadn't deleted it, and __init__.py didn't import
_impl, there would still be no binding. Yet the importer would still
import and make the module available (presumably it "knows" to do this
since it was not already in sys.modules). The question really is that
since in our example pkg._impl is still in sys.modules, why won't the
importer add it to the pkg namespace again as it previous had? I would
imagine this is either by design, or is a case that was never
considered.

> for _impl because you deleted it. By the way, if you have a `normal'
> package that doesn't do anything with the name _impl, after the import
> the pkg module namespace will have got a binding for _impl although it is not
> in your code. It will have been put there by the import code.

Yes, this was noted further down in the original post with an example.


From tom.sully at gmx.com  Sat Jul 25 15:27:37 2009
From: tom.sully at gmx.com (Tom)
Date: Sat, 25 Jul 2009 20:27:37 +0100
Subject: Removing newlines from string on windows (without replacing)
Message-ID: <1248550057.5509.86.camel@ubuntu.ubuntu-domain>

This is my first post to this mailing list, so hi :)

I have an annoying problem. While I mainly use Linux when I distribute
this program to friends and on the internet, it'll get used on Windows.
So, I tested my python program on my Windows Vista dual boot, running
the same version of python (2.6) as my Linux, and got an error at the
following code.

s = sauce.replace("\n", "")

Sauce is a string, read from a file, that I need to remove newlines
from. This code works fine in Linux, but not in Windows. rstrip("\n")
won't work for me, so anybody know how to get this working on Windows?

Thanks! :D

--print "Tom"



From rhodri at wildebst.demon.co.uk  Sat Jul 25 15:53:51 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sat, 25 Jul 2009 20:53:51 +0100
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com>
	<7ct4b8F29mednU1@mid.uni-berlin.de> <24654439.post@talk.nabble.com>
Message-ID: <op.uxm2v1t6a8ncjz@gnudebst>

On Sat, 25 Jul 2009 03:50:54 +0100, Dr. Phillip M. Feldman  
<pfeldman at verizon.net> wrote:

>
> Here's a simple-minded example:
>
> def dumbfunc(xs):
>    for x in xs:
>       print x
>
> This function works fine if xs is a list of floats, but not if it is  
> single
> float.  It can be made to work as follows:
>
> def dumbfunc(xs):
>    if isinstance(xs,(int,float,complex)): xs= [xs]
>    for x in xs:
>       print x
>
> Having to put such extra logic into practically every function is one of  
> the
> annoying things about Python.

If you persist in treating <language 1> as if it was <language 2>, then
your code will always be ugly, and often buggy.  Unless we're talking
natural languages, in which case Yoda-like you will sound.

Fundamentally, your problem is your assertion that it is reasonable to
allow users to treat a single object as if it were wrapped in a list.
In Python, it is not reasonable, for the reasons that you are spending
so much time complaining about.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From tack at urandom.ca  Sat Jul 25 16:00:02 2009
From: tack at urandom.ca (Jason Tackaberry)
Date: Sat, 25 Jul 2009 16:00:02 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
Message-ID: <1248552002.4390.2.camel@willow>

On Sat, 2009-07-25 at 11:30 -0700, Michal Kwiatkowski wrote:
> Is there a way to tell if a generator has been exhausted using pure
> Python code? I've looked at CPython sources and it seems that

Upon a cursory look, after a generator 'gen' is exhausted (meaning
gen.next() has raised StopIteration), it seems that gen.gi_frame will be
None.

Cheers,
Jason.	



From rknop at pobox.com  Sat Jul 25 16:08:17 2009
From: rknop at pobox.com (Rob Knop)
Date: Sat, 25 Jul 2009 15:08:17 -0500
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com>
Message-ID: <q3z63dgv83y.fsf@antonio.tmnwh.net>

Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

> www.trevp.com/tlslite

Thanks, but that looks like a library for setting up a secure connection
between two ends.  What I need is the ability to encrypt with a public
key in Python, where that public key was generated in Java as described,
and where the cipertext can later be decrypted with the corresponding
secret key in Java.

-- 
--Rob Knop
  E-mail:    rknop at pobox.com
  Home Page: http://www.pobox.com/~rknop/
  Blog:      http://www.sonic.net/~rknop/blog/


From rhodri at wildebst.demon.co.uk  Sat Jul 25 16:08:54 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sat, 25 Jul 2009 21:08:54 +0100
Subject: Removing newlines from string on windows (without replacing)
In-Reply-To: <1248550057.5509.86.camel@ubuntu.ubuntu-domain>
References: <1248550057.5509.86.camel@ubuntu.ubuntu-domain>
Message-ID: <op.uxm3k4z1a8ncjz@gnudebst>

On Sat, 25 Jul 2009 20:27:37 +0100, Tom <tom.sully at gmx.com> wrote:

> This is my first post to this mailing list, so hi :)
>
> I have an annoying problem. While I mainly use Linux when I distribute
> this program to friends and on the internet, it'll get used on Windows.
> So, I tested my python program on my Windows Vista dual boot, running
> the same version of python (2.6) as my Linux, and got an error at the
> following code.
>
> s = sauce.replace("\n", "")

What error?  (I don't let Vista in the house.)

> Sauce is a string, read from a file, that I need to remove newlines
> from. This code works fine in Linux, but not in Windows. rstrip("\n")
> won't work for me, so anybody know how to get this working on Windows?

Why won't rstrip("\n") work?  Is rstrip() OK instead, or does trailing
whitespace matter to you?

To provide a partial answer, your problem probably lies in the different
ways Windows and Linux treat ends of lines.  Under Linux, "\n" is the
line terminator.  Under Windows, it's "\r\n".  If you opened your file
in "byte mode" with open("myfile.txt", "rb"), you will be given all the
bytes in the file, including those extra "\r" characters on Windows.  If
you open your file in text mode with open("myfile.txt, "r") instead, the
line endings are converted to "\n" on both Windows and Linux.

If my crystal ball has proved faulty, giving us more details will help
get a more sensible answer.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From http  Sat Jul 25 16:10:43 2009
From: http (Paul Rubin)
Date: 25 Jul 2009 13:10:43 -0700
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com>
	<q3z63dgv83y.fsf@antonio.tmnwh.net>
Message-ID: <7xiqhgmsl8.fsf@ruckus.brouhaha.com>

Rob Knop <rknop at pobox.com> writes:
> > www.trevp.com/tlslite
> 
> Thanks, but that looks like a library for setting up a secure connection
> between two ends.  What I need is the ability to encrypt with a public
> key in Python, where that public key was generated in Java as described,
> and where the cipertext can later be decrypted with the corresponding
> secret key in Java.

Yes, I think that library has the function that you want.  It's just
X509 DER encoding.


From constant.beta at gmail.com  Sat Jul 25 16:20:11 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Sat, 25 Jul 2009 13:20:11 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<mailman.3715.1248552511.8015.python-list@python.org>
Message-ID: <2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>

On Jul 25, 10:00?pm, Jason Tackaberry <t... at urandom.ca> wrote:
> On Sat, 2009-07-25 at 11:30 -0700, Michal Kwiatkowski wrote:
> > Is there a way to tell if a generator has been exhausted using pure
> > Python code? I've looked at CPython sources and it seems that
>
> Upon a cursory look, after a generator 'gen' is exhausted (meaning
> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
> None.

Only in Python 2.5 or higher though. I need to support Python 2.3 and
2.4 as well, sorry for not making that clear in the original post.

Cheers,
mk


From news123 at free.fr  Sat Jul 25 16:29:29 2009
From: news123 at free.fr (News123)
Date: Sat, 25 Jul 2009 22:29:29 +0200
Subject: available formats and params for Image.save()
In-Reply-To: <mailman.3647.1248428867.8015.python-list@python.org>
References: <4a6833dd$0$22599$426a34cc@news.free.fr>
	<mailman.3647.1248428867.8015.python-list@python.org>
Message-ID: <4a6b6b29$0$435$426a74cc@news.free.fr>

Thanks a lot Gabriel,

Your answer is perfect.

I was only looking in part II of the PIL manual and overlooked the
Appendix :-(.

I also apreciate
Image.ID , Image.SAVE , Image.OPEN

I saw them when typing
dir Image
but I never had the idea of calling Image.init() first

bye

N




Gabriel Genellina wrote:
> En Thu, 23 Jul 2009 06:56:45 -0300, News123 <news123 at free.fr> escribi?:
> 
>> Somehow I have difficulties reading the documentation for PIL (Image)
>>
>> Is there an easy way to know which formats are supported and what their
>> names are?
> 
> py> import PIL
> py> from PIL import Image
> py> Image.ID
> []
> py> Image.init()
> py> Image.ID
> ['PNG', 'ARG', 'BMP', 'BUFR', 'CUR', 'PCX', 'DCX', 'EPS', 'FITS', 'FLI',
> 'FPX',
> 'GBR', 'GIF', 'GRIB', 'HDF5', 'ICNS', 'ICO', 'IM', 'IMT', 'IPTC',
> 'JPEG', 'MCIDA
> S', 'TIFF', 'MIC', 'MPEG', 'MSP', 'PCD', 'PIXAR', 'PPM', 'PSD', 'SGI',
> 'SPIDER',
>  'SUN', 'TGA', 'WBMP', 'WMF', 'XBM', 'XPM', 'XVTHUMB']
> py> Image.OPEN.keys()
> ['PCX', 'ICNS', 'HDF5', 'SUN', 'MIC', 'EPS', 'MSP', 'FLI', 'FITS',
> 'GBR', 'WBMP'
> , 'PCD', 'PIXAR', 'BUFR', 'PPM', 'WMF', 'SGI', 'BMP', 'TGA', 'DCX',
> 'ICO', 'CUR'
> , 'XPM', 'TIFF', 'JPEG', 'SPIDER', 'GIF', 'GRIB', 'IM', 'IMT', 'IPTC',
> 'FPX', 'X
> BM', 'MPEG', 'PSD', 'ARG', 'XVTHUMB', 'PNG', 'MCIDAS']
> py> Image.SAVE.keys()
> ['XBM', 'PCX', 'SPIDER', 'HDF5', 'TIFF', 'BUFR', 'EPS', 'JPEG', 'MSP',
> 'GRIB', '
> GIF', 'BMP', 'IM', 'PPM', 'PDF', 'FITS', 'PALM', 'WBMP', 'WMF', 'PNG']
> 
>> Is there an easy way to know which parameters are supported by
>> Image.save(). How can I list them where are they documented?
> 
> That depends on the format being used. The PIL handbook lists the
> standard formats used and their parameters:
> http://www.pythonware.com/library/pil/handbook/index.htm
> 
>> I'm at a complete loss at finding out what parameters the save function
>> accepts for saving a JPG file or a PNG file
> 
> http://www.pythonware.com/library/pil/handbook/format-jpeg.htm
> 


From mwawrzyczek at gmail.com  Sat Jul 25 16:33:01 2009
From: mwawrzyczek at gmail.com (marekw2143)
Date: Sat, 25 Jul 2009 13:33:01 -0700 (PDT)
Subject: Adding method from one class to another class or to instance of 
	another class
References: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
	<mailman.3678.1248463055.8015.python-list@python.org>
Message-ID: <953308c3-671f-4604-9562-d37767e600a4@g6g2000vbr.googlegroups.com>

Thanks for your responses. im_func is all I need. I considered
subclassing, wchih is more easy to extend, but I needed some quick way
to add a method to another class.

Regards,
Marek


From robert.kern at gmail.com  Sat Jul 25 16:57:23 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sat, 25 Jul 2009 15:57:23 -0500
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<24654439.post@talk.nabble.com>
Message-ID: <h4frjl$2vm$1@ger.gmane.org>

On 2009-07-24 21:50, Dr. Phillip M. Feldman wrote:
> Here's a simple-minded example:
>
> def dumbfunc(xs):
>     for x in xs:
>        print x
>
> This function works fine if xs is a list of floats, but not if it is single
> float.  It can be made to work as follows:
>
> def dumbfunc(xs):
>     if isinstance(xs,(int,float,complex)): xs= [xs]
>     for x in xs:
>        print x
>
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

I have spent the last ten years writing scientific code in Python (i.e. that 
which otherwise might be written in Matlab), and I can guarantee you that you do 
not need to put such extra logic in practically every function. Even when 
naively translating code from Matlab, it's not often necessary.

By the way, are you familiar with numpy? If you are converting code from Matlab, 
you will almost certainly need it. We have a number of functions that make these 
kinds of operations easy when they are in fact necessary. For example, we have 
isscalar() and atleast_1d().

   def dumbfunc(xs):
     xs = numpy.atleast_1d(xs)
     for x in xs:
       print x

http://numpy.scipy.org/

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From robert.kern at gmail.com  Sat Jul 25 16:59:30 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sat, 25 Jul 2009 15:59:30 -0500
Subject: len() should always return something
In-Reply-To: <7cvs3fF24hjh7U1@mid.uni-berlin.de>
References: <24639361.post@talk.nabble.com>
	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>
	<7cvs3fF24hjh7U1@mid.uni-berlin.de>
Message-ID: <h4frnj$2vm$2@ger.gmane.org>

On 2009-07-25 02:55, Diez B. Roggisch wrote:
> Dr. Phillip M. Feldman schrieb:
>> Here's a simple-minded example:
>>
>> def dumbfunc(xs):
>> for x in xs:
>> print x
>>
>> This function works fine if xs is a list of floats, but not if it is
>> single
>> float. It can be made to work as follows:
>>
>> def dumbfunc(xs):
>> if isinstance(xs,(int,float,complex)): xs= [xs]
>> for x in xs:
>> print x
>>
>> Having to put such extra logic into practically every function is one
>> of the
>> annoying things about Python.
>
> And where comes "len(xs)" into play here? What you want is iteration
> over scalars.

He explained in another post that iteration is another feature along the same 
lines that he would want for scalars.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From lie.1296 at gmail.com  Sat Jul 25 18:30:30 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 26 Jul 2009 08:30:30 +1000
Subject: Failed Regression Test: What socket.gethostname() is supposed to
	return?
Message-ID: <h4g127$gai$1@ger.gmane.org>

In my laptop, socket.gethostname() returned my username, and causing one
of python's "make test" regression test to error (test_socket):

======================================================================
ERROR: testSockName (test.test_socket.GeneralModuleTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File
"/var/tmp/portage/dev-lang/python-2.5.4-r3/work/Python-2.5.4/Lib/test/test_socket.py",
line 456, in testSockName
    my_ip_addr = socket.gethostbyname(socket.gethostname())
gaierror: (-2, 'Name or service not known')

----------

since on my system socket.gethostname() returns 'lieryan', and since
socket.gethostbyname('lieryan') does not resolve to anything; the test
becomes an error.

My system is Gentoo, but I think this also happened on Ubuntu (still on
this laptop). The trunk failed in similar manner.

Do I have a misconfigured system or is the test faulty?

For convenience, the relevant test code (taken from trunk):

=======================
def testSockName(self):
    # Testing getsockname()
    port = self._get_unused_port()
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.bind(("0.0.0.0", port))
    name = sock.getsockname()
    # XXX(nnorwitz): http://tinyurl.com/os5jz seems to indicate
    # it reasonable to get the host's addr in addition to 0.0.0.0.
    # At least for eCos.  This is required for the S/390 to pass.
    my_ip_addr = socket.gethostbyname(socket.gethostname())
    self.assertTrue(name[0] in ("0.0.0.0", my_ip_addr), '%s invalid' %
name[0])
    self.assertEqual(name[1], port)
=======================


lieryan at lieryan ~/Desktop/pythontrunk/trunk $ ./python -m test.regrtest
test_socket
Could not find '/home/lieryan/Desktop/pythontrunk/trunk/Lib/test' in
sys.path to remove it
test_socket
test test_socket failed -- Traceback (most recent call last):
  File
"/home/lieryan/Desktop/pythontrunk/trunk/Lib/test/test_socket.py", line
493, in testSockName
    my_ip_addr = socket.gethostbyname(socket.gethostname())
gaierror: [Errno -2] Name or service not known

1 test failed:
    test_socket

I tracked the code for socket.gethostname() and socket.gethostbyname()
and found that they are simply a wrapper for gethostname() from #import
<unistd.h> (http://linux.die.net/man/2/gethostname) and gethostbyname()
from #import <netdb.h> (http://linux.die.net/man/3/gethostbyname). A
simple test in C found that the C's equivalent to
gethostbyname(gethostname()) returns a null pointer (used to indicate
error, per documentation).

So, the question is: what is socket.gethostname() is supposed to return
that will be a valid argument for socket.gethostbyname()?

PS: I found an MSDN article by Microsoft stating that
gethostbyname(gethostname) is guaranteed to always succeed
(http://msdn.microsoft.com/en-us/library/ms738527(VS.85).aspx); is this
guarantee also true in linux?



From marcusw at cox.net  Sat Jul 25 18:42:26 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 25 Jul 2009 18:42:26 -0400
Subject: len() should always return something
In-Reply-To: <m2eis4etyb.fsf@cs.uu.nl>
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<m2tz11fatt.fsf@cs.uu.nl>
	<027af2b3$0$5185$c3e8da3@news.astraweb.com>
	<m2eis4etyb.fsf@cs.uu.nl>
Message-ID: <h4g1ok$2tj2$1@adenine.netfront.net>

On 7/25/2009 10:08 AM, Piet van Oostrum wrote:
>>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:
> 
>> SD> Ambiguity essentially boils down to being unable to reasonably predict 
>> SD> the expectation of the coder. I say "reasonably", because if you allow 
>> SD> unreasonable situations, everything is "ambiguous":
> 
> That's for me the reason that len(42) is ambiguous. The OP apparently
> had 1 as expectation, whereas my first thought was the minimal number of
> bits to represent the number and 7.5 million came later :=). The number
> of bits I certainly find reasonable, and I would find the number of
> decimal digits equally reasonable. More so than 1, actually. 1 as the
> length of an int doesn't give any information.
Well, for my two cents, I will say that the number of binary bits or 
decimal digits is certainly the most sensible return value, and that the 
former is the most useful, because the latter can be got with 
len(str(42)). However, the former can also be (/slightly/ less)easily 
got with len(bin(42))-2...

I also think that "Explicit is better than implicit." says that there 
should be no return value in this case, as any return value would be 
implicit.

Marcus


From ben+python at benfinney.id.au  Sat Jul 25 19:10:40 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 26 Jul 2009 09:10:40 +1000
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
Message-ID: <877hxw4avj.fsf@benfinney.id.au>

Michal Kwiatkowski <constant.beta at gmail.com> writes:

> I may be missing something obvious here. Is there a better way to tell
> if a given generator object is still active or not?

    foo = the_generator_object
    try:
        do_interesting_thing_that_needs(foo.next())
    except StopIteration:
        generator_is_exhausted()

In other words, don't LBYL, because it's EAFP. Whatever you need to do
that requires the next item from the generator, do that; you'll get a
specific exception if the generator is exhausted.

-- 
 \      ?Courteous and efficient self-service.? ?caf?, southern France |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From max at alcyone.com  Sat Jul 25 19:21:39 2009
From: max at alcyone.com (Erik Max Francis)
Date: Sat, 25 Jul 2009 16:21:39 -0700
Subject: len() should always return something
In-Reply-To: <027a9f1a$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>

Steven D'Aprano wrote:
> But it's not "practically every function". It's hardly any function at 
> all -- in my code, I don't think I've ever wanted this behavior. I would 
> consider it an error for function(42) and function([42]) to behave the 
> same way. One is a scalar, and the other is a vector -- they're different 
> things, it's poor programming practice to treat them identically.
> 
> (If Matlab does this, so much the worse for Matlab, in my opinion.)

There's actually good reason to do this in heavily matrix-oriented 
specialized languages; there are numerous applications where scalars and 
1x1 matrices are mathematically equivalent.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   Gods are born and die, but the atom endures.
    -- Alexander Chase


From clp2 at rebertia.com  Sat Jul 25 19:30:44 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 25 Jul 2009 16:30:44 -0700
Subject: len() should always return something
In-Reply-To: <04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
Message-ID: <50697b2c0907251630s6e4f7e0en6876b3609eb4fa5@mail.gmail.com>

On Sat, Jul 25, 2009 at 4:21 PM, Erik Max Francis<max at alcyone.com> wrote:
> Steven D'Aprano wrote:
>>
>> But it's not "practically every function". It's hardly any function at all
>> -- in my code, I don't think I've ever wanted this behavior. I would
>> consider it an error for function(42) and function([42]) to behave the same
>> way. One is a scalar, and the other is a vector -- they're different things,
>> it's poor programming practice to treat them identically.
>>
>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
>
> There's actually good reason to do this in heavily matrix-oriented
> specialized languages; there are numerous applications where scalars and 1x1
> matrices are mathematically equivalent.

The pertinent issue here being that Python, as a language, is neither
matrix-oriented nor special-purpose. :)

Cheers,
Chris
-- 
http://blog.rebertia.com


From davea at ieee.org  Sat Jul 25 20:35:05 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 25 Jul 2009 20:35:05 -0400
Subject: strange python scripting error
In-Reply-To: <h4fu50$9pe$1@ger.gmane.org>
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>	<mailman.3636.1248390216.8015.python-list@python.org>	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>	<948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>	<0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>	<4A6AEA22.1030207@ieee.org>
	<h4fu50$9pe$1@ger.gmane.org>
Message-ID: <4A6BA4B9.5090800@ieee.org>



Dennis Lee Bieber wrote:
> On Sat, 25 Jul 2009 07:18:58 -0400, Dave Angel <davea at ieee.org>
> declaimed the following in gmane.comp.python.general:
>
>   
>> Another thing I'd point out is that some ftp programs will do this 
>> conversion as the file is being sent between a local DOS machine and a 
>> Unix machine on the internet.
>>
>>     
> 	"some ftp programs"?
>
> 	Line end conversion is the whole reason, to my knowledge, for text
> mode transfer, vs binary mode transfer.
>
> <snip>
>
>   
Perhaps I should have said "most ftp programs," or even "all ftp 
programs," but I don't feel qualified to make such a generalization.  In 
any case, I don't currently use such automatic conversion when I'm doing 
transfers because I like to be able to see exactly what's there, and I 
don't have another way to directly examine the remote end.

The FTP I use is an add-on for Firefox (FireFTP), and although it has 
text and "auto" modes, it's buried in the Tools->options menu, and the 
main panel just does a transfer using whichever mode was selected.  
Rather than risking corrupting the (mostly binary) files, I choose to 
use binary mode all the time.

DaveA



From scriptlearner at gmail.com  Sat Jul 25 21:03:37 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Sat, 25 Jul 2009 18:03:37 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com> 
	<mailman.3720.1248558305.8015.python-list@python.org>
Message-ID: <96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>

I decided to go with one big log file, which will be shared by all
threads (child and parent).  A log message Queue is used to store all
log entries, and a customized logger thread will get log entries from
the Queue.

#from the logger thread#
    def run(self):
        while self.flag == 1: #if the flag is set to 0, the logger
thread should exit
            try:
                 entry = self.q.get()
            except Empty:
                 self.logger.debug('cant find any log entry')
                 continue
            except:
                 self.logger.error("Unexpected error:", sys.exc_info()
[0])
                 raise
            #do whatever that should be done
        self.logger.info("logger thread done") #should see this
message in log file as well
    def off(self):
        self.logger.info('turning off flag')
        self.flag = 0


#in parent thread#
        logItemQ.put('We are done, lets stop the logger now.')
        time.sleep(1) #it seems that the logger thread cannot exit if
I put a sleep here
        myLog.off() #off is called successfully
        myLog.join()


I put an off method to turn off a flag so the logger thread knows it
should exit.  However, the last log message (the one 'We are done,
lets stop the logger now.') won't be logged if I call myLog.off() and
myLog.join() immediately.  So, I put a time.sleep(1) to make sure the
logger thread has enough time to finish it's job.  Unfortunately, now
the logger thread simply won't exit, and I don't see the message
'logger thread done'.  I can't figure out at which point it hangs,
since I don't any new log entry but the thread simply won't exit.
Am I taking a right approach by using a flag?  Should I lock the flag?


From python at mrabarnett.plus.com  Sat Jul 25 21:30:00 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 26 Jul 2009 02:30:00 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
	<mailman.3720.1248558305.8015.python-list@python.org>
	<96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>
Message-ID: <4A6BB198.4040209@mrabarnett.plus.com>

scriptlearner at gmail.com wrote:
> I decided to go with one big log file, which will be shared by all
> threads (child and parent).  A log message Queue is used to store all
> log entries, and a customized logger thread will get log entries from
> the Queue.
> 
> #from the logger thread#
>     def run(self):
>         while self.flag == 1: #if the flag is set to 0, the logger
> thread should exit
>             try:
>                  entry = self.q.get()
>             except Empty:
>                  self.logger.debug('cant find any log entry')
>                  continue
>             except:
>                  self.logger.error("Unexpected error:", sys.exc_info()
> [0])
>                  raise
>             #do whatever that should be done
>         self.logger.info("logger thread done") #should see this
> message in log file as well
>     def off(self):
>         self.logger.info('turning off flag')
>         self.flag = 0
> 
> 
> #in parent thread#
>         logItemQ.put('We are done, lets stop the logger now.')
>         time.sleep(1) #it seems that the logger thread cannot exit if
> I put a sleep here
>         myLog.off() #off is called successfully
>         myLog.join()
> 
> 
> I put an off method to turn off a flag so the logger thread knows it
> should exit.  However, the last log message (the one 'We are done,
> lets stop the logger now.') won't be logged if I call myLog.off() and
> myLog.join() immediately.  So, I put a time.sleep(1) to make sure the
> logger thread has enough time to finish it's job.  Unfortunately, now
> the logger thread simply won't exit, and I don't see the message
> 'logger thread done'.  I can't figure out at which point it hangs,
> since I don't any new log entry but the thread simply won't exit.
> Am I taking a right approach by using a flag?  Should I lock the flag?

self.q.get() will block if the queue is empty, so the Empty exception is
never raised.

What's happening is that the parent thread puts the final message into
the queue, sleeps, and then clears the flag; meanwhile, the logging
thread gets the message, writes it out, checks the flag, which is still
set, and then tries to get the next message. The queue is empty, so the
.get() blocks.

The simplest solution is not to use a flag, but the sentinel trick. The
parent thread can put, say, None into the queue after the last message;
when the logging thread gets None, it knows it should terminate.



From max at alcyone.com  Sat Jul 25 21:47:07 2009
From: max at alcyone.com (Erik Max Francis)
Date: Sat, 25 Jul 2009 18:47:07 -0700
Subject: len() should always return something
In-Reply-To: <mailman.3723.1248564649.8015.python-list@python.org>
References: <24639361.post@talk.nabble.com>
	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
	<mailman.3723.1248564649.8015.python-list@python.org>
Message-ID: <O_idnfu_uNcGKPbXnZ2dnUVZ_tidnZ2d@giganews.com>

Chris Rebert wrote:
> On Sat, Jul 25, 2009 at 4:21 PM, Erik Max Francis<max at alcyone.com> wrote:
>> Steven D'Aprano wrote:
>>> But it's not "practically every function". It's hardly any function at all
>>> -- in my code, I don't think I've ever wanted this behavior. I would
>>> consider it an error for function(42) and function([42]) to behave the same
>>> way. One is a scalar, and the other is a vector -- they're different things,
>>> it's poor programming practice to treat them identically.
>>>
>>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
>> There's actually good reason to do this in heavily matrix-oriented
>> specialized languages; there are numerous applications where scalars and 1x1
>> matrices are mathematically equivalent.
> 
> The pertinent issue here being that Python, as a language, is neither
> matrix-oriented nor special-purpose. :)

Yes.  And I was responding to the comment that such a feature of a 
language would a priori be poor design.  It _isn't_ poor design for 
special purpose languages.  Python isn't one of them, but Matlab _is_.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   More fodder for the new lost generation
    -- Nik Kershaw


From clp2 at rebertia.com  Sat Jul 25 22:39:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 25 Jul 2009 19:39:13 -0700
Subject: len() should always return something
In-Reply-To: <O_idnfu_uNcGKPbXnZ2dnUVZ_tidnZ2d@giganews.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
	<mailman.3723.1248564649.8015.python-list@python.org>
	<O_idnfu_uNcGKPbXnZ2dnUVZ_tidnZ2d@giganews.com>
Message-ID: <50697b2c0907251939u4c159290qf700640721e88e3a@mail.gmail.com>

On Sat, Jul 25, 2009 at 6:47 PM, Erik Max Francis<max at alcyone.com> wrote:
> Chris Rebert wrote:
>>
>> On Sat, Jul 25, 2009 at 4:21 PM, Erik Max Francis<max at alcyone.com> wrote:
>>>
>>> Steven D'Aprano wrote:
>>>>
>>>> But it's not "practically every function". It's hardly any function at
>>>> all
>>>> -- in my code, I don't think I've ever wanted this behavior. I would
>>>> consider it an error for function(42) and function([42]) to behave the
>>>> same
>>>> way. One is a scalar, and the other is a vector -- they're different
>>>> things,
>>>> it's poor programming practice to treat them identically.
>>>>
>>>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
>>>
>>> There's actually good reason to do this in heavily matrix-oriented
>>> specialized languages; there are numerous applications where scalars and
>>> 1x1
>>> matrices are mathematically equivalent.
>>
>> The pertinent issue here being that Python, as a language, is neither
>> matrix-oriented nor special-purpose. :)
>
> Yes. ?And I was responding to the comment that such a feature of a language
> would a priori be poor design. ?It _isn't_ poor design for special purpose
> languages. ?Python isn't one of them, but Matlab _is_.

I was agreeing with your point actually. That was what I was trying to
convey in my post. Apparently I wasn't as successful in that regard as
I'd hoped.

- Chris
-- 
http://blog.rebertia.com


From martin at v.loewis.de  Sun Jul 26 00:07:21 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 06:07:21 +0200
Subject: uniicode and executing a process with subprocess.call,
	or os.system
In-Reply-To: <mailman.3381.1247956757.8015.python-list@python.org>
References: <mailman.3381.1247956757.8015.python-list@python.org>
Message-ID: <4a6bd67a$0$7423$9b622d9e@news.freenet.de>

> I am very confused about unicode. Can someone point me in the right
> direction?

Try Python 3.1. This should accept Unicode strings directly for sp.call,
so you wouldn't need to encode first.

Regards,
Martin


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Sun Jul 26 00:56:59 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Sun, 26 Jul 2009 00:56:59 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
Message-ID: <h4gnmr$8cl$1@news.eternal-september.org>

On 2009-07-25 00:55:26 -0400, Carl Banks <pavlovevidence at gmail.com> said:

> But please don't put it on the same level as PHP.  Their situations
> have almost nothing in common.

Their situations have much in common; Python attracted programmers away 
from (for example) C++, becuse python is easier to master; Then php 
came along and attracted programmers away from (for example) python, 
because php is easier to master.

This doesn't mean they're on the same level - in fact, if you read 
carefully you'll see my original post said as much: python attracted 
average programmers; php attracted mediocre programmers and even some 
non-programmers, which means that php is clearly a lesser language than 
python.
-- 
Raffael Cavallaro



From nagle at animats.com  Sun Jul 26 01:47:37 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 25 Jul 2009 22:47:37 -0700
Subject: MySQLdb for Python 3.1 getting close?
In-Reply-To: <4a67e912$0$1603$742ec2ed@news.sonic.net>
References: <4a67e912$0$1603$742ec2ed@news.sonic.net>
Message-ID: <4a6bed48$0$1648$742ec2ed@news.sonic.net>

(This is actually a repost; outgoing netnews server was down for a while.)
John Nagle wrote:
>   Is MySQLdb available for Python 3.1 yet?
> 
>   http://sourceforge.net/projects/mysql-python/
> 
> says the last supported Python version is 2.5.  Any progress in sight?
> 
>                 John Nagle   


From nagle at animats.com  Sun Jul 26 01:52:18 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 25 Jul 2009 22:52:18 -0700
Subject: non-owning references?
In-Reply-To: <h4capd$sn3$01$1@news.t-online.com>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<h4capd$sn3$01$1@news.t-online.com>
Message-ID: <4a6bee61$0$1648$742ec2ed@news.sonic.net>

Peter Otten wrote:
> Utpal Sarkar wrote:
> 
>> Is there a way I can tell a variable that the object it is pointing
>> too is not owned by it, in the sense that if it is the only reference
>> to the object it can be garbage collected?
> 
> http://docs.python.org/library/weakref.html

    Yes.  Weak references can be quite useful.  I have a version of
BeautifulSoup in which all the "upward" and "backwards" links are
weak references, but the "downward" and "forwards" links are strong
references.  This breaks the loops in the data structure, and thus
trees and subtrees will go away when no longer required, without
requiring a GC cycle.

				John Nagle


From israel.unterman at gmail.com  Sun Jul 26 01:52:36 2009
From: israel.unterman at gmail.com (is un)
Date: Sat, 25 Jul 2009 22:52:36 -0700 (PDT)
Subject: multiprocessing and __main__
Message-ID: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>

Hi,

Trying the multiprocessing module for the first time, I spent quite a
bit on making this code run:

from multiprocessing import Process
import time

def my_process():
    i = 0
    while 1:
        print i
        i += 1
        time.sleep(0.5)


p = Process(target=my_process, args=())
p.start()

print 'Process started'

The result was not what I expected, it seems like the process restarts
all the time, and the message 'Process started' keeps getting
printed...

Going back to the documentation, I realized that the doc was really
serious about the line:
if __name__ == '__main__' .. which I always ignore, and by changing
the code to

if __name__ == '__main__':
    p = Process(target=my_process, args=())
    p.start()

    print 'Process started'

the problem was solved.
So my question is what actually happens when I call p.start()? Is the
entry file reloaded under a different module name?

Thanks
iu2


From israel.unterman at gmail.com  Sun Jul 26 01:55:24 2009
From: israel.unterman at gmail.com (is un)
Date: Sat, 25 Jul 2009 22:55:24 -0700 (PDT)
Subject: multiprocessing and __main__
References: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>
Message-ID: <88e64585-e719-4a1a-ade9-7d54b3884503@r2g2000yqm.googlegroups.com>

Me again, fix a type in my question:
 So my question is what actually happens when I call p.start()? Is the
 *entire* file reloaded under a different module name?
>
> Thanks
> iu2



From bhardwajjayesh7 at gmail.com  Sun Jul 26 02:23:11 2009
From: bhardwajjayesh7 at gmail.com (golu)
Date: Sat, 25 Jul 2009 23:23:11 -0700 (PDT)
Subject: code debugging
Message-ID: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>

here is a code which crawls links sent to it. theres some problem with
the retrieve_url function ,plz help me out in debugging the fuction
retrive_url. This function retrives pages and saves them in file
#TODO:Visited dict grows in size it needs to be handled smartly
#Moreover server program needs to be in sync with the client eg.
Myrobot
#Take care of tag - 'if modified since',repeated links,hash links
#This is the client side of the distributed crawling framework
#It gets the list of urls to be crawled
#Then crawls the urls and stores the pages in a temporary archive
#which is then transferred to the server or grey_matter
import httplib
import os
import sys
import urlparse
import urllib2
import urllib
import zipfile
import threading

from socket import *
PAGE_DIR="C:/users/jayesh/
pages/"                                          # directory where the
web pages are stored temporarily
 
# before transfer to the grey_matter
visited=
{}                                                                 # a
dict to remember visited urls
ROBOT_COUNT=4


def fget():
    """ This function retrieves the zipped file
     containing the list of urls from the grey_matter and
     saves them in a local file 'list.txt'. """

    httplib.HTTPConnection.debuglevel=1
    request=urllib2.Request('http://192.168.153.57/list.zip')
#Requesting the zipped file
    request.add_header('Accept-encoding','gzip')           #containing
the list of urls
    opener=urllib2.build_opener()
    flag=1
    s='Waiting for server'
    while flag==1:
     try:
      op=opener.open(request)
      flag=0
     except:
         s=s+'*'
         print s
    f=open('list.zip',"wb")
    f.write(op.read())
    f.close()
    z=zipfile.ZipFile('list.zip')
    p=z.namelist()
    g=open('list.txt',"wb")
    g.write(z.read(p[0]))
    g.close()
    print 'got zipped file'

def compress():
    """ This function compresses the crawled pages and stores them in
        a single compressed file ready to be sent to the
grey_matter."""

    zfile=zipfile.ZipFile('C:/xampp/htdocs/pages.zip',mode='w')
    for fil in os.listdir(PAGE_DIR):
        full=os.path.join(PAGE_DIR,fil)
        zfile.write(full,fil)
        os.remove(full)
    os.rmdir(PAGE_DIR)             #Removing the directory after
transfer to grey_matter


x=0
class robot(threading.Thread):
    """ The main robot class which does the crawling of listed
    urls it recieves from the grey matter. It uses 3 threads which
    crawl the listed urls synchronously."""

    def __init__(self,urllist,urllistlock,dblock):
        threading.Thread.__init__(self)
        self.urllist=urllist
        self.urllistlock=urllistlock
        self.dblock=dblock

    def popurl(self):
        """ This method pops out urls from the urls file one by one
        and sends them for retrieval."""

        self.urllistlock.acquire(1)
        if(len(self.urllist)<1):
            Nexturl=None
        else:
            Nexturl=self.urllist[0]
            if Nexturl[-1]=='\n':Nexturl=Nexturl[:-1]
            del self.urllist[0]
        self.urllistlock.release()
        return Nexturl

    def retrieve_url(self,url):
        """ The main method of the robot class and is called
        run method to retrieve the given urls from the web."""
        global x
        if url is not None:

         try:
            if visited.has_key(url): return
            pieces=urlparse.urlparse(url)
            filepath=pieces[2]
            if filepath != '':
             filepath=filepath[1:]
             filename=filepath.split("/")[-1]
            else:
              filename=x+'.htm'
              x+=1

            path=os.path.join(PAGE_DIR,filename)
            url=urlparse.urlunparse(pieces)
            p=url.rfind('#')                   #temporary
            if p!=-1:
                url=url[:p]

            visited[url]=1
            m=urllib2.urlopen(url)

            fopen=open(path,'wb')

            fopen.seek(0)
            fopen.write(url+'|')

            fopen.write(m.read())
            fopen.close()
            print url ,'retrieved'

         except IOError:
            print url
            print "ERROR:OOPS! THE URL CAN'T BE RETRIEVED"

        return

    def run(self):
        while(1):
            url=self.popurl()
            if url is None:
                break
            try:
             self.retrieve_url(url)
            except:sys.exit()

if __name__=='__main__':

  s=socket(AF_INET,SOCK_STREAM)
  s.bind(('',444))
  s.listen(5)
  q,v=s.accept()
  count=1
  print 'Connecting...'
  while 1:
    print 'Phase: %s' %(count)
    message=q.recv(3)

    if(message!='yes'):continue
    print 'Connected'
    count=count+1
    fget()             # Calling the fget method to get the url list
from
                       # grey_matter(server).
    try:
     os.mkdir(PAGE_DIR)
    except: print 'Cant make dir'
    try:
     f=open('list.txt','r')
     urllist=f.readlines()
     f.close()
    except:
        print 'Error opening urls file'
        sys.exit()
    print 'startting threads'
    urllistlock=threading.Lock()
    dblock=threading.Lock()
    botlist=[]
    for X in range(0,ROBOT_COUNT):
         newbot=robot(urllist,urllistlock,dblock)
         newbot.setName('X')
         botlist.append(newbot)
         newbot.start()

    for X in range(0,ROBOT_COUNT):
         botlist[X].join()

    compress()
    try:
     q.send('yes')
    except:
        print 'socket disconnected'
        print sys.exit()




From clp2 at rebertia.com  Sun Jul 26 02:28:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 25 Jul 2009 23:28:48 -0700
Subject: code debugging
In-Reply-To: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
References: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
Message-ID: <50697b2c0907252328t70ecd0ddp20898ddf497b5190@mail.gmail.com>

On Sat, Jul 25, 2009 at 11:23 PM, golu<bhardwajjayesh7 at gmail.com> wrote:
> here is a code which crawls links sent to it. theres some problem with
> the retrieve_url function ,plz help me out in debugging the fuction
> retrive_url. This function retrives pages and saves them in file

Please specify exactly what the problem is that you are experiencing.
If you are getting an error, please provide the error message and full
traceback.

Cheers,
Chris
-- 
http://blog.rebertia.com


From bhardwajjayesh7 at gmail.com  Sun Jul 26 02:33:27 2009
From: bhardwajjayesh7 at gmail.com (golu)
Date: Sat, 25 Jul 2009 23:33:27 -0700 (PDT)
Subject: code debugging
References: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
	<mailman.3727.1248589730.8015.python-list@python.org>
Message-ID: <c7dd7062-fcf8-49e9-aae0-cd3c88f6b204@d4g2000prc.googlegroups.com>

On Jul 26, 11:28?am, Chris Rebert <c... at rebertia.com> wrote:
> On Sat, Jul 25, 2009 at 11:23 PM, golu<bhardwajjaye... at gmail.com> wrote:
> > here is a code which crawls links sent to it. theres some problem with
> > the retrieve_url function ,plz help me out in debugging the fuction
> > retrive_url. This function retrives pages and saves them in file
>
> Please specify exactly what the problem is that you are experiencing.
> If you are getting an error, please provide the error message and full
> traceback.
>
> Cheers,
> Chris
> --http://blog.rebertia.com

i want to save pages in a directory and i m using the urls to get
filenames. The program gets stuck in the saving step.can u suggest me
a way to save a page e.g google.com as a file google.html


From bhardwajjayesh7 at gmail.com  Sun Jul 26 02:57:35 2009
From: bhardwajjayesh7 at gmail.com (golu)
Date: Sat, 25 Jul 2009 23:57:35 -0700 (PDT)
Subject: web page retrieve problems
Message-ID: <16343e3d-1be4-422b-8bff-c07fa4aa4c54@j9g2000prh.googlegroups.com>

the following function retrieves pages from the web and saves them in
a specified dir. i want to extract the respective filenames from the
urls e.g the page code.google.com shud be saved as code-google.htm  or
something similar. can u suggest me a way to do it
def retrieve_url(self,url):
        """ The main method of the robot class and is called
        run method to retrieve the given urls from the web."""

        if url is not None:

         try:
            if visited.has_key(url): return
            pieces=urlparse.urlparse(url)
            filepath=pieces[2]
            if filepath != '':
             filepath=filepath[1:]
             filename=filepath.split("/")[-1]
            else:
              filename='home.htm'


            path=os.path.join(PAGE_DIR,filename)
            url=urlparse.urlunparse(pieces)
            p=url.rfind('#')                   #temporary
            if p!=-1:
                url=url[:p]

            visited[url]=1
            m=urllib2.urlopen(url)

            fopen=open(path,'wb')

            fopen.seek(0)
            fopen.write(url+'|')

            fopen.write(m.read())
            fopen.close()
            print url ,'retrieved'

         except IOError:
            print url
            print "ERROR:OOPS! THE URL CAN'T BE RETRIEVED"

        return


From emmanuel.surleau at gmail.com  Sun Jul 26 03:42:33 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Sun, 26 Jul 2009 09:42:33 +0200
Subject: len() should always return something
In-Reply-To: <h4g1ok$2tj2$1@adenine.netfront.net>
References: <24639361.post@talk.nabble.com> <m2eis4etyb.fsf@cs.uu.nl>
	<h4g1ok$2tj2$1@adenine.netfront.net>
Message-ID: <200907260942.33841.emmanuel.surleau@gmail.com>

On Sunday 26 July 2009 00:42:26 Marcus Wanner wrote:
> On 7/25/2009 10:08 AM, Piet van Oostrum wrote:
> >>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:
> >>
> >> SD> Ambiguity essentially boils down to being unable to reasonably
> >> predict SD> the expectation of the coder. I say "reasonably", because if
> >> you allow SD> unreasonable situations, everything is "ambiguous":
> >
> > That's for me the reason that len(42) is ambiguous. The OP apparently
> > had 1 as expectation, whereas my first thought was the minimal number of
> > bits to represent the number and 7.5 million came later :=). The number
> > of bits I certainly find reasonable, and I would find the number of
> > decimal digits equally reasonable. More so than 1, actually. 1 as the
> > length of an int doesn't give any information.
>
> Well, for my two cents, I will say that the number of binary bits or
> decimal digits is certainly the most sensible return value, and that the
> former is the most useful, because the latter can be got with
> len(str(42)). However, the former can also be (/slightly/ less)easily
> got with len(bin(42))-2...


For my two eurocents, I'd expect such an operator to be called "sizeof" and 
when applied to a collection, to also return the number of bits it uses. I 
don't think a 'len' function has meaning when applied to something else than a 
collection, really...

> I also think that "Explicit is better than implicit." says that there
> should be no return value in this case, as any return value would be
> implicit.

Agreed.

Cheers,

Emm


From hendrik at microcorp.co.za  Sun Jul 26 03:48:49 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 26 Jul 2009 09:48:49 +0200
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
Message-ID: <200907260948.49293.hendrik@microcorp.co.za>

On Saturday 25 July 2009 20:30:54 Michal Kwiatkowski wrote:
> Hi,
>
> Is there a way to tell if a generator has been exhausted using pure
> Python code? I've looked at CPython sources and it seems that
> something like "active"/"exhausted" attribute on genobject is missing
> from the API. For the time being I am using a simple C extension to
> look at f_stacktop pointer of the generator frame, which seems to
> differentiate active generators from exhausted ones. See
> http://bazaar.launchpad.net/~ruby/pythoscope/support-python2.3/annotate/286
>/pythoscope/_util.c#L16 for complete source code.
>
> I may be missing something obvious here. Is there a better way to tell
> if a given generator object is still active or not?

Is there a reason why you cannot just call the next method and handle
the StopIteration when it happens?

- Hendrik


From emmanuel.surleau at gmail.com  Sun Jul 26 03:50:42 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Sun, 26 Jul 2009 09:50:42 +0200
Subject: non-owning references?
In-Reply-To: <8763di5d1d.fsf@benfinney.id.au>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<8763di5d1d.fsf@benfinney.id.au>
Message-ID: <200907260950.42765.emmanuel.surleau@gmail.com>

On Friday 24 July 2009 17:14:06 you wrote:
> Hrvoje Niksic <hniksic at xemacs.org> writes:
> > The term "variable" is used in the Python language reference and
> > elsewhere
>
> Yes. It should also be abundantly clear from the constant stream of
> confused newbies on this point that its usage of that term is different
> to what many expect from usage elsewhere.
>
> > and is quite compatible with how other popular languages (Java, PHP,
> > Lisp, ...) use it. Please stop complaining about valid terminology; it
> > is not helpful.
>
> I disagree with your assertions.
>
> Rather than yet another round of this tedious debate, I merely point
> interested readers to <URL:http://effbot.org/zone/python-objects.htm>
> and ask them to draw their own conclusion on how compatible their
> pre-existing ?variable? concept is with Python's object reference
> model.

Then I must be one of these "confused newbies". After a cursory look at your 
article, I don't see a difference with Java variables (as long as we speak 
about non-primitive types).

Cheers,

Emm


From martin at v.loewis.de  Sun Jul 26 04:04:12 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 10:04:12 +0200
Subject: C-API, tp_dictoffset vs tp_members
In-Reply-To: <7cl194F28ojoqU1@mid.uni-berlin.de>
References: <7cl194F28ojoqU1@mid.uni-berlin.de>
Message-ID: <4A6C0DFC.4030702@v.loewis.de>

> When would I use PyObject_SetAttrString/tp_dictoffset instead of tp_members? 

When I have a variable list of attributes, and cannot statically know
what those attributes might be.

> I have a predefined set of members, some of which are optional.

Having optional fields is also a good reason.

> The problem 
> I had with an embedded dictionary was that I can't see its elements using 
> "dir()".

How so? That should work fine.

> Now I just converted to using tp_members, and it still seems to 
> work correctly for the cases I tested.

So how do you do optional fields now? In particular, how would you do
optional integers?

> Even better, I can declare the fields 
> as read-only then and add doc-strings. So, I wonder, what made the original 
> author[2] use tp_dictoffset instead? 

Most likely, it was the simplest approach. This code only wants to set
the attributes, and never read them. It's easier to maintain: if you
want to add a field with tp_members, you have to change multiple places,
and you have to consider garbage collection (assuming you have embedded
objects). With tp_dictoffset, adding another attribute is easy.

Regards,
Martin


From jessica.1980.smith at gmail.com  Sun Jul 26 04:12:47 2009
From: jessica.1980.smith at gmail.com (Jessica R Smith)
Date: Sun, 26 Jul 2009 01:12:47 -0700 (PDT)
Subject: I am trying to compile python 2.6.2 on my Mac
Message-ID: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>

Hello,
I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7

I downloaded python 2.6.2 from here:
  - http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2

I unpacked it.

I ran these shell commands:
  - ./configure --prefix=/pt/p
  - make

Near the end of the make output I see this message:

. Failed to find the necessary bits to build these modules:
. _bsddb             gdbm               linuxaudiodev
. ossaudiodev        readline           spwd
. sunaudiodev
. To find the necessary bits, look in setup.py in detect_modules() for
the module's name.

I looked in setup.py in detect_modules()

It is not clear to me how to proceed.

I think that I want the module: "readline"

I doubt I need the other modules like linuxaudiodev, etc.

If you have any clues or opinions on how I can build the module
"readline",
please feel free to share.

Thanks,
JRS


From nobody at nowhere.com  Sun Jul 26 04:13:30 2009
From: nobody at nowhere.com (Nobody)
Date: Sun, 26 Jul 2009 09:13:30 +0100
Subject: Failed Regression Test: What socket.gethostname() is supposed
	to	return?
References: <mailman.3722.1248561042.8015.python-list@python.org>
Message-ID: <pan.2009.07.26.08.13.29.766000@nowhere.com>

On Sun, 26 Jul 2009 08:30:30 +1000, Lie Ryan wrote:

> since on my system socket.gethostname() returns 'lieryan', and since
> socket.gethostbyname('lieryan') does not resolve to anything; the test
> becomes an error.
> 
> My system is Gentoo, but I think this also happened on Ubuntu (still on
> this laptop). The trunk failed in similar manner.
> 
> Do I have a misconfigured system or is the test faulty?

Misconfigured system.

> I tracked the code for socket.gethostname() and socket.gethostbyname()
> and found that they are simply a wrapper for gethostname() from #import
> <unistd.h> (http://linux.die.net/man/2/gethostname) and gethostbyname()
> from #import <netdb.h> (http://linux.die.net/man/3/gethostbyname). A
> simple test in C found that the C's equivalent to
> gethostbyname(gethostname()) returns a null pointer (used to indicate
> error, per documentation).
> 
> So, the question is: what is socket.gethostname() is supposed to return
> that will be a valid argument for socket.gethostbyname()?

gethostname() returns the hostname.

gethostbyname() returns some information about the host (specifically,
aliases and IP addresses) obtained by platform-specific means (which
normally includes /etc/hosts and DNS, and may also include NIS, LDAP, and
others; see the nsswitch.conf manpage for more details).

Python's socket.gethostname() simply returns the first IP address;
socket.gethostbyname_ex() returns all of the information which libc's
gethostbyname() provides.

In order for gethostbyname() to work, the host must be listed in one of
the databases which it uses. The simplest way to achieve this is to add an
entry to /etc/hosts, e.g.:

	192.168.0.2 lieryan.yourdomain.com lieryan

or just:

	192.168.0.2 lieryan

> PS: I found an MSDN article by Microsoft stating that
> gethostbyname(gethostname) is guaranteed to always succeed
> (http://msdn.microsoft.com/en-us/library/ms738527(VS.85).aspx); is this
> guarantee also true in linux?

No.



From gagsl-py2 at yahoo.com.ar  Sun Jul 26 04:14:34 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 26 Jul 2009 05:14:34 -0300
Subject: multiprocessing and __main__
References: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>
Message-ID: <op.uxn06klpx6zn5v@gabriel.sleipnir-bsas>

En Sun, 26 Jul 2009 02:52:36 -0300, is un <israel.unterman at gmail.com>  
escribi?:

> Trying the multiprocessing module for the first time, I spent quite a
> bit on making this code run:
> [...]
> The result was not what I expected, it seems like the process restarts
> all the time, and the message 'Process started' keeps getting
> printed...
>
> Going back to the documentation, I realized that the doc was really
> serious about the line:
> if __name__ == '__main__' .. which I always ignore, and by changing
> the code to
>
> if __name__ == '__main__':
>     p = Process(target=my_process, args=())
>     p.start()
>
>     print 'Process started'
>
> the problem was solved.
> So my question is what actually happens when I call p.start()? Is the
> entry file reloaded under a different module name?

The multiprocessing module handles multiple (separate) processes. On  
Windows, a new Python interpreter is launched; on other OSs a different  
approach is used. In any case, you get distinct and separate processes,  
each one with its own set of loaded modules, etc.

-- 
Gabriel Genellina



From clp2 at rebertia.com  Sun Jul 26 04:37:43 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 26 Jul 2009 01:37:43 -0700
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
Message-ID: <50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>

On Sun, Jul 26, 2009 at 1:12 AM, Jessica R
Smith<jessica.1980.smith at gmail.com> wrote:
> Hello,
> I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7
>
> I downloaded python 2.6.2 from here:
> ?- http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2
>
> I unpacked it.
>
> I ran these shell commands:
> ?- ./configure --prefix=/pt/p
> ?- make
>
> Near the end of the make output I see this message:
>
> . Failed to find the necessary bits to build these modules:
> . _bsddb ? ? ? ? ? ? gdbm ? ? ? ? ? ? ? linuxaudiodev
> . ossaudiodev ? ? ? ?readline ? ? ? ? ? spwd
> . sunaudiodev
> . To find the necessary bits, look in setup.py in detect_modules() for
> the module's name.
>
> I looked in setup.py in detect_modules()
>
> It is not clear to me how to proceed.
>
> I think that I want the module: "readline"
>
> I doubt I need the other modules like linuxaudiodev, etc.
>
> If you have any clues or opinions on how I can build the module
> "readline",
> please feel free to share.

You need to install the GNU Readline library
(http://tiswww.case.edu/php/chet/readline/rltop.html), which the
module depends on.

You might consider installing Python through MacPorts or Fink instead,
as they automate the compilation and installation process and take
care of dependencies (such as GNU Readline) for you:
http://www.macports.org/
http://www.finkproject.org/

Cheers,
Chris
-- 
http://blog.rebertia.com


From constant.beta at gmail.com  Sun Jul 26 04:45:21 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Sun, 26 Jul 2009 01:45:21 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
Message-ID: <2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>

On Jul 26, 1:10?am, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Michal Kwiatkowski <constant.b... at gmail.com> writes:
> > I may be missing something obvious here. Is there a better way to tell
> > if a given generator object is still active or not?
>
> ? ? foo = the_generator_object
> ? ? try:
> ? ? ? ? do_interesting_thing_that_needs(foo.next())
> ? ? except StopIteration:
> ? ? ? ? generator_is_exhausted()
>
> In other words, don't LBYL, because it's EAFP. Whatever you need to do
> that requires the next item from the generator, do that; you'll get a
> specific exception if the generator is exhausted.

The thing is I don't need the next item. I need to know if the
generator has stopped without invoking it. Why - you may ask. Well,
the answer needs some explaining.

I'm working on the Pythoscope project (http://pythoscope.org) and I
use tracing mechanisms of CPython (sys.settrace) to capture function
calls and values passed to and from them. Now, the problem with
generators is that when they are ending (i.e. returning instead of
yielding) they return a None, which is in fact indistinguishable from
"yield None". That means I can't tell if the last captured None was in
fact yielded or is a bogus value which should be rejected. Let me show
you on an example.

import sys

def trace(frame, event, arg):
    if event != 'line':
        print frame, event, arg
    return trace

def gen1():
    yield 1
    yield None

def gen2():
    yield 1

sys.settrace(trace)
print "gen1"
g1 = gen1()
g1.next()
g1.next()
print "gen2"
g2 = gen2()
[x for x in g2]
sys.settrace(None)

The first generator isn't finished, it yielded 1 and None. Second one
is exhausted after yielding a single value (1). The problem is that,
under Python 2.4 or 2.3 both invocations will generate the same trace
output. So, to know whether the last None was actually a yielded value
I need to know if a generator is active or not.

Your solution, while gives me an answer, is not acceptable because
generators can cause side effects (imagine call to launch_rockets()
before the next yield statement ;).

Cheers,
mk


From jessica.1980.smith at gmail.com  Sun Jul 26 05:01:31 2009
From: jessica.1980.smith at gmail.com (Jessica Smith)
Date: Sun, 26 Jul 2009 02:01:31 -0700
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
	<50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
Message-ID: <ac1384480907260201l53d49d44h33e2e884d3bf31e8@mail.gmail.com>

Chris thanks!!

other members:

I read this:
  - http://chrismiles.livejournal.com/25648.html

I did this:
  - install mac ports
  - port install readline
  - vi  setup.py

    def detect_modules(self):
        # Ensure that /usr/local is always used
        add_dir_to_list(self.compiler.library_dirs, '/opt/local/lib')
        add_dir_to_list(self.compiler.include_dirs, '/opt/local/include')

  - configure --prefix=/pt/p
  - make
  - make install

I'm happy now!

JRS


On 7/26/09, Chris Rebert <clp2 at rebertia.com> wrote:
> On Sun, Jul 26, 2009 at 1:12 AM, Jessica R
> Smith<jessica.1980.smith at gmail.com> wrote:
>> Hello,
>> I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7
>>
>> I downloaded python 2.6.2 from here:
>> ?- http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2
>>
>> I unpacked it.
>>
>> I ran these shell commands:
>> ?- ./configure --prefix=/pt/p
>> ?- make
>>
>> Near the end of the make output I see this message:
>>
>> . Failed to find the necessary bits to build these modules:
>> . _bsddb ? ? ? ? ? ? gdbm ? ? ? ? ? ? ? linuxaudiodev
>> . ossaudiodev ? ? ? ?readline ? ? ? ? ? spwd
>> . sunaudiodev
>> . To find the necessary bits, look in setup.py in detect_modules() for
>> the module's name.
>>
>> I looked in setup.py in detect_modules()
>>
>> It is not clear to me how to proceed.
>>
>> I think that I want the module: "readline"
>>
>> I doubt I need the other modules like linuxaudiodev, etc.
>>
>> If you have any clues or opinions on how I can build the module
>> "readline",
>> please feel free to share.
>
> You need to install the GNU Readline library
> (http://tiswww.case.edu/php/chet/readline/rltop.html), which the
> module depends on.
>
> You might consider installing Python through MacPorts or Fink instead,
> as they automate the compilation and installation process and take
> care of dependencies (such as GNU Readline) for you:
> http://www.macports.org/
> http://www.finkproject.org/
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>


From __peter__ at web.de  Sun Jul 26 05:08:10 2009
From: __peter__ at web.de (Peter Otten)
Date: Sun, 26 Jul 2009 11:08:10 +0200
Subject: strange error when trying to log something
References: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>
	<h49ah5$hv3$02$1@news.t-online.com> <h4fau1$gvn$1@panix3.panix.com>
Message-ID: <h4h6d7$bbu$00$1@news.t-online.com>

Aahz wrote:

> In article <h49ah5$hv3$02$1 at news.t-online.com>,
> Peter Otten  <__peter__ at web.de> wrote:
>>
>>I have a hunch that you are triggering a reload() somewhere. Example:
>>
>>Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
>>[GCC 4.3.3] on linux2
>>Type "help", "copyright", "credits" or "license" for more information.
>>>>> import weakref
>>>>> weakref.WeakValueDictionary()
>><WeakValueDictionary at 140598938447312>
>>>>> import UserDict
>>>>> reload(UserDict)
>><module 'UserDict' from '/usr/lib/python2.6/UserDict.pyc'>
>>>>> weakref.WeakValueDictionary()
>>Traceback (most recent call last):
>>  File "<stdin>", line 1, in <module>
>>  File "/usr/lib/python2.6/weakref.py", line 51, in __init__
>>    UserDict.UserDict.__init__(self, *args, **kw)
>>TypeError: unbound method __init__() must be called with UserDict instance
>>as first argument (got WeakValueDictionary instance instead)
> 
> Nice sleuthing!  How did you figure that out?

Roughly: 

- The poster's description/remedy makes no sense (to me); have a look at the 
traceback.
- Nothing suspicious except the actual error message. Isn't 
WeakValueDictionary a UserDict? Verify.
- There must be two different UserDict classes. This can happen to an 
unsuspecting user by importing the main script or by doing a reload().
UserDict is unlikely to be the main script, and web frameworks (django was 
mentioned) often use a reload mechanism to avoid frequent server restarts.
- Reproduce the error.

Peter



From gagsl-py2 at yahoo.com.ar  Sun Jul 26 05:19:52 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 26 Jul 2009 06:19:52 -0300
Subject: code debugging
References: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
	<mailman.3727.1248589730.8015.python-list@python.org>
	<c7dd7062-fcf8-49e9-aae0-cd3c88f6b204@d4g2000prc.googlegroups.com>
Message-ID: <op.uxn37exfx6zn5v@gabriel.sleipnir-bsas>

En Sun, 26 Jul 2009 03:33:27 -0300, golu <bhardwajjayesh7 at gmail.com>  
escribi?:

> i want to save pages in a directory and i m using the urls to get
> filenames. The program gets stuck in the saving step.can u suggest me
> a way to save a page e.g google.com as a file google.html

You may use str.translate to replace/remove all undesired characters:

py> import string
py> valid = string.ascii_letters+string.digits+'.'
py> invalid = ''.join(chr(x) for x in range(256) if chr(x) not in valid)
py> table = string.maketrans(invalid, '_'*len(invalid))
py> x = 'http://docs.python.org/library/string.html'
py> x.translate(table)
'http___docs.python.org_library_string.html'

See http://docs.python.org/library/stdtypes.html#str.translate

-- 
Gabriel Genellina



From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 05:45:03 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 09:45:03 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
Message-ID: <027c168c$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 16:21:39 -0700, Erik Max Francis wrote:

> Steven D'Aprano wrote:
>> But it's not "practically every function". It's hardly any function at
>> all -- in my code, I don't think I've ever wanted this behavior. I
>> would consider it an error for function(42) and function([42]) to
>> behave the same way. One is a scalar, and the other is a vector --
>> they're different things, it's poor programming practice to treat them
>> identically.
>> 
>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
> 
> There's actually good reason to do this in heavily matrix-oriented
> specialized languages; there are numerous applications where scalars and
> 1x1 matrices are mathematically equivalent.


I'm curious what those applications are, because regular multiplication 
behaves differently depending on whether you have a 1x1 matrix or a 
scalar:

[[2]]*[[1, 2, 3], [2, 3, 4]] is not defined

2*[[1, 2, 3], [2, 3, 4]] = [[2, 4, 6], [2, 6, 8]]


I'm curious as to what these applications are, and what they're actually 
doing. Kronecker multiplication perhaps? Do you have some examples of 
those applications?



-- 
Steven


From doomster at knuut.de  Sun Jul 26 05:45:37 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Sun, 26 Jul 2009 11:45:37 +0200
Subject: C-API, tp_dictoffset vs tp_members
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
Message-ID: <7d2mu7F27a9tbU1@mid.uni-berlin.de>

"Martin v. L?wis" wrote:
>> I have a predefined set of members, some of which are optional.
> 
> Having optional fields is also a good reason.

What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then? I would
 have though that the former describes an optional field, because the
 behaviour of accessing it when it is NULL is the same as accessing a
 nonexistent field. However, I see that it still appears in the dir()
 output even if it is NULL, so it seems I'm misunderstanding this.

>> The problem
>> I had with an embedded dictionary was that I can't see its elements using
>> "dir()".
> 
> How so? That should work fine.

>>> import example
>>> x = example.Example()
>>> dir(x)
['__class__', '__delattr__', '__doc__', '__getattribute__',
'__hash__', '__init__', '__new__', '__reduce__', '__reduce_ex__',
'__repr__', '__setattr__', '__str__']
>>> x.example_attribute
'example value'

The 'example_attribute' can be accessed, but it is not visible in the
dir() output. The code for this is below.


>> Now I just converted to using tp_members, and it still seems to
>> work correctly for the cases I tested.
> 
> So how do you do optional fields now? In particular, how would you do
> optional integers?

See above, I would expect T_OBJECT_EX to do that.

Thanks!

Uli



/* example.c

 gcc -Wall example.c -shared -I /usr/include/python2.5 -o example.so
*/

#include <Python.h>
#include <structmember.h>

typedef struct {
    PyObject_HEAD
    PyObject* dict;
} Example;

static void
Example_dealloc(PyObject* self)
{
    Example* ex = (Example*)self;
    Py_XDECREF(ex->dict);
    self->ob_type->tp_free(self);
}

static PyObject *
Example_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
    Example* self;
    PyObject* attr;

    self = (Example*)type->tp_alloc(type, 0);
    if(self==NULL)
        return NULL;

    self->dict = PyDict_New();
    if(self->dict==NULL) {
        Py_DECREF(self);
        return NULL;
    }

    attr = PyString_FromString("example value");
    if(PyObject_SetAttrString((PyObject*)self, "example_attribute", attr)<0) {
        Py_DECREF(self);
        return NULL;
    }

    return (PyObject*)self;
}

static PyTypeObject ExampleType = {
    PyObject_HEAD_INIT(NULL)
    0,                         /*ob_size*/
    "example.Example",         /*tp_name*/
    sizeof(Example),           /*tp_basicsize*/
    0,                         /*tp_itemsize*/
    Example_dealloc,           /*tp_dealloc*/
    0,                         /*tp_print*/
    0,                         /*tp_getattr*/
    0,                         /*tp_setattr*/
    0,                         /*tp_compare*/
    0,                         /*tp_repr*/
    0,                         /*tp_as_number*/
    0,                         /*tp_as_sequence*/
    0,                         /*tp_as_mapping*/
    0,                         /*tp_hash */
    0,                         /*tp_call*/
    0,                         /*tp_str*/
    0,                         /*tp_getattro*/
    0,                         /*tp_setattro*/
    0,                         /*tp_as_buffer*/
    Py_TPFLAGS_DEFAULT,        /*tp_flags*/
    0,                         /* tp_doc */
    0,                         /* tp_traverse */
    0,                         /* tp_clear */
    0,                         /* tp_richcompare */
    0,                         /* tp_weaklistoffset */
    0,                         /* tp_iter */
    0,                         /* tp_iternext */
    0,                         /* tp_methods */
    0,                         /* tp_members */
    0,                         /* tp_getset */
    0,                         /* tp_base */
    0,                         /* tp_dict */
    0,                         /* tp_descr_get */
    0,                         /* tp_descr_set */
    offsetof(Example, dict),   /* tp_dictoffset */
    0,                         /* tp_init */
    0,                         /* tp_alloc */
    Example_new,               /* tp_new */
};

void
initexample(void) 
{
    PyObject* m;

    if (PyType_Ready(&ExampleType) < 0)
        return;

    m = Py_InitModule3("example", 0,
                       "Example module that creates an extension type.");

    if (m == NULL)
      return;

    Py_INCREF(&ExampleType);
    PyModule_AddObject(m, "Example", (PyObject*)&ExampleType);
}



From israelu at elbit.co.il  Sun Jul 26 05:50:15 2009
From: israelu at elbit.co.il (iu2)
Date: Sun, 26 Jul 2009 02:50:15 -0700 (PDT)
Subject: multiprocessing and __main__
References: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>
Message-ID: <fa60d2c6-1016-4c1a-8a6c-00e3e5fa8e23@r2g2000yqm.googlegroups.com>

On Jul 26, 8:52?am, is un <israel.unter... at gmail.com> wrote:
> Hi,
>
> Trying the multiprocessing module for the first time, I spent quite a
> bit on making this code run:
>
> from multiprocessing import Process
> import time
>
> def my_process():
> ? ? i = 0
> ? ? while 1:
> ? ? ? ? print i
> ? ? ? ? i += 1
> ? ? ? ? time.sleep(0.5)
>
> p = Process(target=my_process, args=())
> p.start()
>
> print 'Process started'
>
> The result was not what I expected, it seems like the process restarts
> all the time, and the message 'Process started' keeps getting
> printed...
>
> Going back to the documentation, I realized that the doc was really
> serious about the line:
> if __name__ == '__main__' .. which I always ignore, and by changing
> the code to
>
> if __name__ == '__main__':
> ? ? p = Process(target=my_process, args=())
> ? ? p.start()
>
> ? ? print 'Process started'
>
> the problem was solved.
> So my question is what actually happens when I call p.start()? Is the
> entry file reloaded under a different module name?
>
> Thanks
> iu2

Ok, I found it, it is nicely documented, I missed it before. Case
closed.


From doomster at knuut.de  Sun Jul 26 05:54:55 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Sun, 26 Jul 2009 11:54:55 +0200
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org>
Message-ID: <7d2nfnF29tk6fU1@mid.uni-berlin.de>

Tom wrote:
> s = sauce.replace("\n", "")
> 
> Sauce is a string, read from a file, that I need to remove newlines
> from. This code works fine in Linux, but not in Windows. rstrip("\n")
> won't work for me, so anybody know how to get this working on Windows?

I'm pretty sure this works regardless of the system. What might change is 
the way that a line is terminated: MS Windows by default uses a CR/LF 
('\r\n') pair, while most other systems just an LF ('\n').

I'd adapt the code to accept either line ending on either system.

If that's not what you want, you should improve your "doesn't work" 
description. ;)

Uli




From max at alcyone.com  Sun Jul 26 06:11:02 2009
From: max at alcyone.com (Erik Max Francis)
Date: Sun, 26 Jul 2009 03:11:02 -0700
Subject: len() should always return something
In-Reply-To: <027c168c$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
	<027c168c$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <ZIOdnSQ36v4ltvHXnZ2dnUVZ_u6dnZ2d@giganews.com>

Steven D'Aprano wrote:
> I'm curious what those applications are, because regular multiplication 
> behaves differently depending on whether you have a 1x1 matrix or a 
> scalar:
> 
> [[2]]*[[1, 2, 3], [2, 3, 4]] is not defined
> 
> 2*[[1, 2, 3], [2, 3, 4]] = [[2, 4, 6], [2, 6, 8]]
> 
> I'm curious as to what these applications are, and what they're actually 
> doing. Kronecker multiplication perhaps? Do you have some examples of 
> those applications?

The most obvious example would be the matrix algebra equivalent of the 
calculation of the dot product, the equivalent of a dot product in 
normal vector algebra.  If you have two 3-vectors (say), u = (u_1, u_2, 
u_3) and v = (v_1, v_2, v_3), then the dot product is the sum of the 
pairwise products of these terms, u dot v = sum_i u_i v_i = u_1 v_1 + 
u_2 v_2 + u_3 v_3.

Nothing revolutionary there.  The matrix way of writing this wouldn't 
obviously work, since multiplying two nx1 or (1xn) matrixes by each 
other is invalid.  But you _can_ multiply a nx1 matrix by an 1xn matrix, 
and you get the equivalent of the dot product:

	u v^T = ( u dot v ),

where the right hand side of the equation is formally a 1x1 matrix 
(intended to be indicated by the parentheses), but you can see how it is 
useful to think of it as just a scalar, because it's really just a 
matrix version of the same thing as a dot product.

This stretches out to other kinds of applications, where, say, in tensor 
calculus, you can think of a contravariant vector as being transformed 
into a covariant vector by the application of the matrix tensor, which 
is written as lowering an index.  The components of the contravariant 
vector can be thought of as a column vector, while the components of a 
covariant vector can be represented with a row vector.  The application 
  of the metric tensor to a contravariant vector turns it into a row 
vector, and then contracting over the two vectors gives you the inner 
product as above.  The applications and contractions can all be 
visualized as matrix multiplications.  (Contrary to a popularization, 
tensors _aren't_ generalizations of matrices, but their components can be.)

It's a bunch of other examples like that where you end up with a 1x1 
matrix that really represents a scalar, and since that was intended 
there really isn't a lot of efficacy to treat it as a separate entity. 
Especially if you're dealing with a special-purpose language where 
everything is really a form of an generalized array representation of 
something _anyway_.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   Scars are like memories. We do not have them removed.
    -- Chmeee


From wilk at flibuste.net  Sun Jul 26 06:22:34 2009
From: wilk at flibuste.net (William Dode)
Date: 26 Jul 2009 10:22:34 GMT
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
	<mailman.3613.1248368814.8015.python-list@python.org>
	<4a696af3$0$442$426a74cc@news.free.fr>
	<mailman.3687.1248467986.8015.python-list@python.org>
Message-ID: <4a6c2e6a$0$424$426a34cc@news.free.fr>

On 24-07-2009, Christian Tismer wrote:
> On 7/24/09 1:04 AM, William Dode wrote:
>> On 23-07-2009, Christian Tismer wrote:
> ...
>
>>> Wasn't the project plan saying the opposite, borrowing
>>> some ideas from psyco? :-)
>>> http://code.google.com/p/unladen-swallow/wiki/ProjectPlan
>>
>> How do you see the future of psyco when unladen-swallow will grab the
>> best of psyco (if they can !) ?
>
> I have no objections, but also no idea so far how that could work.
> Sounded like an unreflected idea to me, without seriously
> checking the possibilities and/or implications. The same
> kind of research apparently did not happen concerning PyPy,
> which IMHO is much more suitable to take advantage from.
>
> This is for the current status of psyco, of course.
> It will change dramatically in the next months, slowly
> adopting some of PyPy's ideas. Then it might start to
> make more sense.

I didn't understand how psyco could use somes PyPy's ideas, i thought 
it's only the opposite... So i was going to read the PyPy's 
documentation : it's fascinating !!!

But how to test it ? The doc says : "When PyPy is translated into an 
executable like pypy-c, the executable contains a full virtual machine 
that can optionally include a Just-In-Time compiler."

Where is this 'option', is there somethings to activate it ?

thx

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From deets at nospam.web.de  Sun Jul 26 06:51:31 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sun, 26 Jul 2009 12:51:31 +0200
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <mailman.3733.1248598894.8015.python-list@python.org>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>	<50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
	<mailman.3733.1248598894.8015.python-list@python.org>
Message-ID: <7d2qpkF29u2uiU1@mid.uni-berlin.de>

Jessica Smith schrieb:
> Chris thanks!!
> 
> other members:
> 
> I read this:
>   - http://chrismiles.livejournal.com/25648.html
> 
> I did this:
>   - install mac ports
>   - port install readline
>   - vi  setup.py
> 
>     def detect_modules(self):
>         # Ensure that /usr/local is always used
>         add_dir_to_list(self.compiler.library_dirs, '/opt/local/lib')
>         add_dir_to_list(self.compiler.include_dirs, '/opt/local/include')
> 
>   - configure --prefix=/pt/p
>   - make
>   - make install
> 
> I'm happy now!

You are aware that under OSX one usually wants a so-called 
framework-build? It's an configure-option.

You don't need the --prefix then (unless you have another python2.6 
installed), and without the FW-build no UI-packages are useable.

Diez


From piet at cs.uu.nl  Sun Jul 26 07:50:57 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 26 Jul 2009 13:50:57 +0200
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
	<mailman.3720.1248558305.8015.python-list@python.org>
	<96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>
	<mailman.3725.1248571777.8015.python-list@python.org>
Message-ID: <m2tz0zd5ni.fsf@cs.uu.nl>

>>>>> MRAB <python at mrabarnett.plus.com> (M) wrote:

>M> scriptlearner at gmail.com wrote:
>>> I decided to go with one big log file, which will be shared by all
>>> threads (child and parent).  A log message Queue is used to store all
>>> log entries, and a customized logger thread will get log entries from
>>> the Queue.
>>> 
>>> #from the logger thread#
>>> def run(self):
>>> while self.flag == 1: #if the flag is set to 0, the logger
>>> thread should exit
>>> try:
>>> entry = self.q.get()
>>> except Empty:
>>> self.logger.debug('cant find any log entry')
>>> continue
>>> except:
>>> self.logger.error("Unexpected error:", sys.exc_info()
>>> [0])
>>> raise
>>> #do whatever that should be done
>>> self.logger.info("logger thread done") #should see this
>>> message in log file as well
>>> def off(self):
>>> self.logger.info('turning off flag')
>>> self.flag = 0
>>> 
>>> 
>>> #in parent thread#
>>> logItemQ.put('We are done, lets stop the logger now.')
>>> time.sleep(1) #it seems that the logger thread cannot exit if
>>> I put a sleep here
>>> myLog.off() #off is called successfully
>>> myLog.join()
>>> 
>>> 
>>> I put an off method to turn off a flag so the logger thread knows it
>>> should exit.  However, the last log message (the one 'We are done,
>>> lets stop the logger now.') won't be logged if I call myLog.off() and
>>> myLog.join() immediately.  So, I put a time.sleep(1) to make sure the
>>> logger thread has enough time to finish it's job.  Unfortunately, now
>>> the logger thread simply won't exit, and I don't see the message
>>> 'logger thread done'.  I can't figure out at which point it hangs,
>>> since I don't any new log entry but the thread simply won't exit.
>>> Am I taking a right approach by using a flag?  Should I lock the flag?

>M> self.q.get() will block if the queue is empty, so the Empty exception is
>M> never raised.

>M> What's happening is that the parent thread puts the final message into
>M> the queue, sleeps, and then clears the flag; meanwhile, the logging
>M> thread gets the message, writes it out, checks the flag, which is still
>M> set, and then tries to get the next message. The queue is empty, so the
>M> .get() blocks.

>M> The simplest solution is not to use a flag, but the sentinel trick. The
>M> parent thread can put, say, None into the queue after the last message;
>M> when the logging thread gets None, it knows it should terminate.

To the OP: a sleep will never do it because you can't be sure how long
the logging thread will lag behind. Most multithreaded `solutions' which
depend on timings are buggy.

If you have more than one thread writing to the log queue one sentinel
won't solve the problem. You would need as many sentinels as there are
threads, and the logger should count the sentinels which can have normal
messages between them. It may be a bit fragile to depend on the number
of threads especially when this number is dynamic. One solution would be
to have special StartLogging and StopLogging objects that are put in the
queue when a thread starts and finishes respectively. The logger can stop
then when the number of StopLogging objects equals the number of
StartLogging objects received and that number is greater than 0. This
presupposes that no new thread will be started after all the others have
finished. The StartLogging objects can also be put in the queue by the
parent when it starts up the threads, which may be more robust because
it has fewer timing dependencies.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From breamoreboy at yahoo.co.uk  Sun Jul 26 07:53:20 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Sun, 26 Jul 2009 12:53:20 +0100
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>
Message-ID: <h4hg2l$kb7$1@ger.gmane.org>

Neil Hodgson wrote:
> casebash:
> 
>> I have searched this list and found out that Python doesn't have a
>> mutable string class (it had an inefficient one, but this was removed
>> in 3.0). Are there any libraries outside the core that offer this?
> 
>    I wrote a gap buffer implementation for Python 2.5 allowing
> character, unicode character and integer elements.
> 
> http://code.google.com/p/gapbuffer/
> 
>    Its not seen much use or any maintenance so is unlikely to work with
> Python 3.x.
> 
>    Neil

I tried this as a learning exercise and found slicing doesn't work 
correctly.

import gapbuffer
print gapbuffer.GapBuffer(range(10))[:]
GapBuffer('i')]

If my sleuthing is correct the problem is with these lines

ilow *= self->itemSize;
ihigh *= self->itemSize;

in GapBuffer_slice being computed before ilow and ihigh are compared to 
anything.

Python 2.6.2 32 bit Windows.

-- 
Kindest regards.

Mark Lawrence.



From helvinlui at gmail.com  Sun Jul 26 08:04:11 2009
From: helvinlui at gmail.com (Helvin)
Date: Sun, 26 Jul 2009 05:04:11 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
	<mailman.2902.1247154895.8015.python-list@python.org>
	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>
	<16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com> 
	<mailman.3611.1248368602.8015.python-list@python.org>
Message-ID: <4ee78bf1-476d-4e41-b9da-c20297aad861@13g2000prl.googlegroups.com>

On Jul 24, 5:03?am, Robert Kern <robert.k... at gmail.com> wrote:
> On 2009-07-23 03:55, Helvin wrote:
>
> > I believe I now have vtkpython.exe. However, my 'import vtk' statement
> > in my python code is not working. The error says something like "no
> > module named vtk".
> > Where do I find modules for vtk inpyqt? Do they exist?
>
> There are no VTK modules inPyQtitself. ThePyQtsupport is in the vtk package
> which can be built with VTK itself. You will need to install VTK and the vtk
> package correctly in order to achieve this. vtkpython.exe is not going to help
> you. Ignore it. After you have built VTK, you need to do an extra step to
> install the vtk package to where your Python interpreter will be able to find it.
>
> Let's say that your build directory is c:\vtkbuild.
>
> ? ?cd \vtkbuild\Wrapping\Python
> ? ?python setup.py install
> ? ?cd \
>
> Now you should be able to import vtk from your normal Python interpreter. If you
> are still having problems, you will need to copy-and-paste exactly what you did
> and what error messages you got. Do not paraphrase error messages.
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
> ? that is made terrible by our own mad attempt to interpret it as though it had
> ? an underlying truth."
> ? ?-- Umberto Eco

Hi Robert,

I realised that vtkpython.exe works, if I drag and drop my .py file on
it. Ie, running my .py file using vtkpython.exe
But my python interpreter does not work with the python file. I have
tried what you suggested.
Below is what I typed in command line, as well as the error that it
produces.

C:\Qt\VTKbin7\Wrapping\Python>python setup.py install
Traceback (most recent call last):
  File "setup.py", line 138, in <module>
    raise "ERROR: Must specify BUILD_TYPE=<config-name> on command
line."
TypeError: exceptions must be classes or instances, not str

Is it just a small error with input format or something?

Thanks so much!
Helvin


From aahz at pythoncraft.com  Sun Jul 26 09:16:39 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 06:16:39 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
Message-ID: <h4hkvn$ef6$1@panix3.panix.com>

In article <h4gnmr$8cl$1 at news.eternal-september.org>,
Raffael Cavallaro  <raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com> wrote:
>On 2009-07-25 00:55:26 -0400, Carl Banks <pavlovevidence at gmail.com> said:
>>
>> But please don't put it on the same level as PHP.  Their situations
>> have almost nothing in common.
>
>Their situations have much in common; Python attracted programmers away 
>from (for example) C++, becuse python is easier to master; Then php 
>came along and attracted programmers away from (for example) python, 
>because php is easier to master.

No, Python attracted programmers away from C++ because it's easier to
write good programs in it, in less time.  There are plenty of expert C++
programmers who switched to Python; your thesis only applies to the
legions of people who found it difficult to learn C++ in the first place.

Moreover, AFAIK PHP never attracted people away from Python; Python was
not particularly popular when PHP was in its heyday.  PHP attracted
people away from Perl and Java and C++.

I'm curious, do you actually know Python at all?  Have you used it for a
serious project?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Sun Jul 26 09:31:06 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Sun, 26 Jul 2009 09:31:06 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<h4hkvn$ef6$1@panix3.panix.com>
Message-ID: <h4hm7q$6g2$1@news.eternal-september.org>

On 2009-07-26 09:16:39 -0400, aahz at pythoncraft.com (Aahz) said:

> There are plenty of expert C++
> programmers who switched to Python;

"plenty" is an absolute term, not a relative term. I sincerely doubt 
that the majority of python users were formerly *expert* C++ 
programmers.

> your thesis only applies to the
> legions of people who found it difficult to learn C++ in the first place.

No, my thesis applies to the overwhelming majority of programmers who 
found it more difficult to *master* (i.e., not merely use) C++ as 
opposed to mastering python. BTW, this is a *complement* not a dis; 
python is a better language than C++ precisely because it is more 
sensibly and elegantly designed than C++ and therefore easier to master.

php represents the same process but farther down the ladder, as it 
were. There's often a tradeoff between ease of mastery and power. 
python hits a sweet spot for many tasks and many programmers, 
especially as compared to C++ (or even lisp, which though more powerful 
than python is more difficult to master. lisp beats C++ on both counts 
imho - more powerful *and* easier to master). php hits a sweet spot 
only in a very restricted domain. Beyond that, it is clearly inferior 
to python which has greater power, but is more difficult to master.


-- 
Raffael Cavallaro



From pauljbarry3 at gmail.com  Sun Jul 26 10:29:44 2009
From: pauljbarry3 at gmail.com (Paul Barry)
Date: Sun, 26 Jul 2009 07:29:44 -0700 (PDT)
Subject: Can't get UDP example to work
Message-ID: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>

I'm trying to get one of the examples from Foundation of Python
Network Programming to work.  Specifically this is the UDP example
from Ch 3.  First there is the server:

#!/usr/bin/env python
# UDP Echo Server - Chapter 3 - udpechoserver.py
import socket, traceback, time

host = '127.0.0.1'                               # Bind to all
interfaces
port = 51423

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host, port))

while 1:
    try:
        message, address = s.recvfrom(8192)
        print "Got message '%s' from %s" % (message, address)

        # Echo it back
        s.sendto(message, address)
        print "Sent response to '%s'" % (address,)

    except (KeyboardInterrupt, SystemExit):
        raise
    except:
        traceback.print_exc()

Next I have a client written in Ruby, which works.  I am posting thing
not to start a Ruby/Python flame war, but to simply prove that the
server works and there are no weird networking issues that would
prevent the Python client from working.  The Ruby code is:

#!/usr/bin/env ruby
require 'socket'

socket = UDPSocket.new
socket.connect ARGV[0], ARGV[1]

puts "Enter data to transmit: "
data = STDIN.gets.chomp

socket.send data, 0
puts "Looking for replies; press Ctrl-C or Ctrl-Break to stop."

loop do
  buf = socket.recvfrom(2048)
  puts buf.first
end

When I start the server and run that, the output looks like this:

$ ch02/udp.rb 127.0.0.1 51423
Enter data to transmit:
foobar
Looking for replies; press Ctrl-C or Ctrl-Break to stop.
foobar

Now, when I try the python example:

#!/usr/bin/env python
# UDP Example - Chapter 2 - udp.py

import socket, sys

host = sys.argv[1]
textport = sys.argv[2]

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
try:
    port = int(textport)
except ValueError:
    # That didn't work.  Look it up instead.
    port = socket.getservbyname(textport, 'udp')

s.connect((host, port))
print "Enter data to transmit: "
data = sys.stdin.readline().strip()
s.sendall(data)

print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
while 1:
    buf = s.recvfrom(2048)
    sys.stdout.write(buf[0])

I don't ever get a response:

$ ch02/udp.py 127.0.0.1 51423
Enter data to transmit:
foobar
Looking for replies; press Ctrl-C or Ctrl-Break to stop.

The server sees the message and says it has sent a reply:

Got message 'foobar' from ('127.0.0.1', 49623)
Sent response to '('127.0.0.1', 49623)'

Any ideas as to why this doesn't work?




From michael at stroeder.com  Sun Jul 26 10:59:42 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Sun, 26 Jul 2009 16:59:42 +0200
Subject: ANN: python-ldap-2.3.9
Message-ID: <mailman.3769.1248697213.8015.python-announce-list@python.org>

Find a new release of python-ldap:

  http://www.python-ldap.org/

python-ldap provides an object-oriented API to access LDAP directory
servers from Python programs. It mainly wraps the OpenLDAP 2.x libs for
that purpose. Additionally it contains modules for other LDAP-related
stuff (e.g. processing LDIF, LDAPURLs and LDAPv3 schema).

Ciao, Michael.

-- 
Michael Str?der
E-Mail: michael at stroeder.com
http://www.stroeder.com

----------------------------------------------------------------

Released 2.3.9 2009-07-26

Changes since 2.3.8:

Lib/
* All modules (ldap, ldif, dsml and ldapurl) have common version number now
* Non-exported function ldif.needs_base64() was abandoned and is now
  implemented as method LDIFWriter._needs_base64_encoding().
  This allows sub-classes of LDIFWriter to implement determining whether
  attribute values have to be base64-encoded in a different manner and is
  the same approach like in class dsml.DSMLWriter.
* LDAPUrlExtension._parse() now gracefully handles LDAP URL extensions
  without explicit exvalue as being set with implicit value None.

Modules/
* New LDAP option constant ldap.OPT_X_SASL_NOCANON supported
  in LDAPObject.get/set_option()


From python at mrabarnett.plus.com  Sun Jul 26 11:07:40 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 26 Jul 2009 16:07:40 +0100
Subject: Can't get UDP example to work
In-Reply-To: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
Message-ID: <4A6C713C.8050806@mrabarnett.plus.com>

Paul Barry wrote:
> I'm trying to get one of the examples from Foundation of Python
> Network Programming to work.  Specifically this is the UDP example
> from Ch 3.  First there is the server:
> 
> #!/usr/bin/env python
> # UDP Echo Server - Chapter 3 - udpechoserver.py
> import socket, traceback, time
> 
> host = '127.0.0.1'                               # Bind to all
> interfaces
> port = 51423
> 
> s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
> s.bind((host, port))
> 
> while 1:
>     try:
>         message, address = s.recvfrom(8192)
>         print "Got message '%s' from %s" % (message, address)
> 
>         # Echo it back
>         s.sendto(message, address)
>         print "Sent response to '%s'" % (address,)
> 
>     except (KeyboardInterrupt, SystemExit):
>         raise
>     except:
>         traceback.print_exc()
> 
> Next I have a client written in Ruby, which works.  I am posting thing
> not to start a Ruby/Python flame war, but to simply prove that the
> server works and there are no weird networking issues that would
> prevent the Python client from working.  The Ruby code is:
> 
> #!/usr/bin/env ruby
> require 'socket'
> 
> socket = UDPSocket.new
> socket.connect ARGV[0], ARGV[1]
> 
> puts "Enter data to transmit: "
> data = STDIN.gets.chomp
> 
> socket.send data, 0
> puts "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> 
> loop do
>   buf = socket.recvfrom(2048)
>   puts buf.first
> end
> 
> When I start the server and run that, the output looks like this:
> 
> $ ch02/udp.rb 127.0.0.1 51423
> Enter data to transmit:
> foobar
> Looking for replies; press Ctrl-C or Ctrl-Break to stop.
> foobar
> 
> Now, when I try the python example:
> 
> #!/usr/bin/env python
> # UDP Example - Chapter 2 - udp.py
> 
> import socket, sys
> 
> host = sys.argv[1]
> textport = sys.argv[2]
> 
> s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> try:
>     port = int(textport)
> except ValueError:
>     # That didn't work.  Look it up instead.
>     port = socket.getservbyname(textport, 'udp')
> 
> s.connect((host, port))
> print "Enter data to transmit: "
> data = sys.stdin.readline().strip()
> s.sendall(data)
> 
> print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> while 1:
>     buf = s.recvfrom(2048)
>     sys.stdout.write(buf[0])
> 
> I don't ever get a response:
> 
> $ ch02/udp.py 127.0.0.1 51423
> Enter data to transmit:
> foobar
> Looking for replies; press Ctrl-C or Ctrl-Break to stop.
> 
> The server sees the message and says it has sent a reply:
> 
> Got message 'foobar' from ('127.0.0.1', 49623)
> Sent response to '('127.0.0.1', 49623)'
> 
> Any ideas as to why this doesn't work?
> 
It works on my PC (Python 2.6.2, Windows XP Pro, service pack 3).


From robert.avery at gmail.com  Sun Jul 26 11:09:02 2009
From: robert.avery at gmail.com (Robert Avery)
Date: Sun, 26 Jul 2009 08:09:02 -0700 (PDT)
Subject: 'Registry' or 'Preference' settings in Mac Python
Message-ID: <35258dc9-941d-42ec-9c35-9361d0c70da7@n11g2000yqb.googlegroups.com>

Is there any way for me to save some sort of global preference for
python that I can read/write at runtime that doesn't involve me
explicitly creating a file?  It may create a file underneath, but I
don't want some path hard coded to my routine.

In Windows, the Registry serves this purpose.  Is there something
similar for Mac?


From deets at nospam.web.de  Sun Jul 26 11:09:26 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sun, 26 Jul 2009 17:09:26 +0200
Subject: cgi.fieldstorage()
In-Reply-To: <13ed9818-aacd-4260-800b-a04177e13681@n11g2000yqb.googlegroups.com>
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
	<f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
	<7cv268F29q0j5U1@mid.uni-berlin.de>
	<13ed9818-aacd-4260-800b-a04177e13681@n11g2000yqb.googlegroups.com>
Message-ID: <7d39t9F2963rqU1@mid.uni-berlin.de>

gert schrieb:
> On Jul 25, 2:33 am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> gert schrieb:
>>
>>> On Jul 24, 7:32 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>>>> gert schrieb:
>>>>> this is a non standard way to store multi part post data on disk
>>>>> def application(environ, response):
>>>>>     with open('/usr/httpd/var/wsgiTemp','w') as f:
>>>>>         while True:
>>>>>             chunk = environ['wsgi.input'].read(8192).decode('latin1')
>>>>>             if not chunk: break
>>>>>             f.write(chunk)
>>>>>     response('200 OK',[])
>>>>>     return ['complete']
>>>>> my question is how do i handle the file, so i can shuffle it into a db
>>>>> using small chunks of memorie ?
>>>> I don't think that's possible with the current DB-API. There is no
>>>> stream-based BLOB-interface (as e.g. JDBC offers).
>>>> So the answer certainly depends on your used RDBMS. For oracle, you
>>>> would be lucky:
>>>> http://cx-oracle.sourceforge.net/html/lob.html
>>>> Other adapters I don't know about.
>>> sqlite :) ok let say for now it would be impossible on a db level, but
>>> before i reach the impossible, i still need to parse the file to
>>> prepare the chunks. How do i do that ? How do i get the chunks without
>>> loading the hole file into memorie ?
>> It's memory - memorie might be some nice dutch girl you know :)
>>
>> Apart from that, your code above does exactly that - reads the data
>> chunkwise. If the WSGI-implementation works proper, this will be the
>> socket's input stream, so there is no memory overhead involved.
>>
>> Now of course if you want to have a multi-pass processing of the file
>> without putting it into memory, then you need to save it to the harddisk
>> befor.
>>
>> But honestly - we are talking about a web-application here. My
>> DSL-connection has 1 MBit upstream, the average server has at least 2GB
>> of memory available - so we are talking 20000 seconds uploading time to
>> fill that memory. Which is about 5 hours. And you are decoding the data
>> to a certain decoding, so we are not talking about binary data here -
>> are you really sure memory is an issue?
>>
> 
> What about some http upload resume features ?

What has that todo with reading data into memory or not? Of course you 
can create continous uploads with HTTP, but a single HTTP-request is a 
single HTTP-request. You can store the requests into individual blobs, 
and then when the overall file upload is finished, concatenate these. If 
you like. Or not, if you don't care, as you can as easily serve them 
even as one stream from those various chunks.

But all of this has nothing todo with the need to not load POST-data 
into memory. This only becomes a problem if you are expecting uploads in 
the hundreds of megabytes.

Diez


From petite.abeille at gmail.com  Sun Jul 26 11:18:17 2009
From: petite.abeille at gmail.com (Petite Abeille)
Date: Sun, 26 Jul 2009 17:18:17 +0200
Subject: 'Registry' or 'Preference' settings in Mac Python
In-Reply-To: <35258dc9-941d-42ec-9c35-9361d0c70da7@n11g2000yqb.googlegroups.com>
References: <35258dc9-941d-42ec-9c35-9361d0c70da7@n11g2000yqb.googlegroups.com>
Message-ID: <68879AA8-CC01-4CA1-815F-88C0DC0F0181@gmail.com>


On Jul 26, 2009, at 5:09 PM, Robert Avery wrote:

> In Windows, the Registry serves this purpose.  Is there something
> similar for Mac?

http://developer.apple.com/documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/Reference/Reference.html

http://developer.apple.com/documentation/CoreFoundation/Reference/CFPreferencesUtils/Reference/reference.html

http://developer.apple.com/documentation/CoreFoundation/Conceptual/CFPreferences/CFPreferences.html

--
PA.
http://alt.textdrive.com/nanoki/



From aahz at pythoncraft.com  Sun Jul 26 11:44:02 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 08:44:02 -0700
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
	<h4av5n$p1l$1@panix3.panix.com>
	<mailman.3648.1248429993.8015.python-list@python.org>
Message-ID: <h4htk2$fmb$1@panix3.panix.com>

In article <mailman.3648.1248429993.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>En Thu, 23 Jul 2009 21:27:35 -0300, Aahz <aahz at pythoncraft.com> escribi?:
>> In article <mailman.3561.1248307942.8015.python-list at python.org>,
>> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>>>
>>> NLMPI
>>
>> What?
>
>IHNFI

What?  Abbreviations are fine, but if someone asks you about one, it
would be nice to just expand it instead of replying with another
abbreviation.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From victorsubervi at gmail.com  Sun Jul 26 11:48:29 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 26 Jul 2009 12:48:29 -0300
Subject: Cannot Get Form To Work
In-Reply-To: <h4a513$dus$1@ger.gmane.org>
References: <4dc0cfea0907230846g4f593219t308c64eec4943f93@mail.gmail.com>
	<h4a513$dus$1@ger.gmane.org>
Message-ID: <4dc0cfea0907260848n1c59793bwd9f2dc1be46e66f1@mail.gmail.com>

Oops. My bad. I did in fact have this line of code before calls to form:

form = cgi.FieldStorage()

I changed the except command from "pass" to "print sys.exc_info()" as per
your suggestion. Still, however, the form just renews itself without
offering any information whatsoever. You can see this here, if you like:
http://13gems.com/test-Calculators_frame.py
TIA,
beno

On Thu, Jul 23, 2009 at 2:01 PM, Dennis Lee Bieber <wlfraed at ix.netcom.com>wrote:

> On Thu, 23 Jul 2009 12:46:16 -0300, Victor Subervi
> <victorsubervi at gmail.com> declaimed the following in
> gmane.comp.python.general:
>
> > sent. Here again is the code:
> >
> > from primeNumbers import primeNumbers
> >
> > try:
> >  lang = form.getfirst('lang', 'en')
>
>         This code is incomplete -- where is "form" created? I see no
> "import"s that might define such...
>
> >  browser = form.getfirst('browser', 'all')
> >  site = form.getfirst('site', 'bridge')
> >  num = form.getfirst('num','')
> > except:
> >  pass
>
>         Since there is no such thing as "form" in the code you posted, the
> first "form.getfirst()" operation will raise an exception. That
> exception is then being ignored by this "pass".
>
>        I'd suggest moving the code that outputs the HTTP response header
> and the HTML prelude material to the top, then replace "pass" with
> something that prints actual exception information (the stuff from
> sys.exc_info() )
> --
>        Wulfraed        Dennis Lee Bieber               KD6MOG
>        wlfraed at ix.netcom.com           wulfraed at bestiaria.com
>                HTTP://wlfraed.home.netcom.com/
>        (Bestiaria Support Staff:               web-asst at bestiaria.com)
>                HTTP://www.bestiaria.com/
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090726/0b190933/attachment.html>

From sjmachin at lexicon.net  Sun Jul 26 11:51:39 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 26 Jul 2009 08:51:39 -0700 (PDT)
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
	<88e8ea19-7106-406a-a531-88c2b6893987@y7g2000yqa.googlegroups.com>
Message-ID: <c7231b06-e619-4ac5-9342-66c164c31595@p10g2000prm.googlegroups.com>

On Jul 23, 11:53?am, Paul McGuire <pt... at austin.rr.com> wrote:
> On Jul 22, 5:43?pm, Filip <pink... at gmail.com> wrote:

>
> # Needs re.IGNORECASE, and can have tag attributes, such as <BR
> CLEAR="ALL">
> line_break_re = re.compile('<br\/?>', re.UNICODE)

Just in case somebody actually uses valid XHTML :-) it might be a good
idea to allow for <br />

> # what about HTML entities defined using hex syntax, such as &#xxxx;
> amp_re = re.compile('\&(?![a-z]+?\;)', re.UNICODE | re.IGNORECASE)

What about the decimal syntax ones? E.g. not only &nbsp; and &#xa0;
but also &#160;

Also, entity names can contain digits e.g. &sup1; &frac34;


From aahz at pythoncraft.com  Sun Jul 26 11:55:18 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 08:55:18 -0700
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au> <87ljmogglz.fsf@benfinney.id.au>
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
	<056f629b-aa63-458a-ae16-ac40a759e446@h11g2000yqb.googlegroups.com>
Message-ID: <h4hu96$8hs$1@panix3.panix.com>

In article <056f629b-aa63-458a-ae16-ac40a759e446 at h11g2000yqb.googlegroups.com>,
Shai  <shai at platonix.com> wrote:
>
>class DocInherit(object):
>    """
>    Docstring inheriting method descriptor
>
>    The class itself is also used as a decorator
>    """

Nice!  Maybe stick this on the Cookbook?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From piet at cs.uu.nl  Sun Jul 26 12:13:22 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 26 Jul 2009 18:13:22 +0200
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
References: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>
	<m2iqhgex8w.fsf@cs.uu.nl>
	<ef5b3dbe-92ab-45cb-a150-f8a921b68c71@r24g2000vbn.googlegroups.com>
Message-ID: <m2ab2rcti5.fsf@cs.uu.nl>

>>>>> ryles <rylesny at gmail.com> (r) wrote:

>r> On Jul 25, 8:57?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>>> >>>>> ryles <ryle... at gmail.com> (r) wrote:
>>> >r> According tohttp://www.python.org/doc/essays/packages.html:
>>> >r> "The import statement first tests whether the item is defined in the
>>> >r> package; if not, it assumes it is a module and attempts to load it."
>>> >r> However, I've noticed that once a module is imported using the
>>> >r> `from pkg import mod' syntax, if its name is deleted from the
>>> >r> package namespace then subsequent imports with `from' will fail.
>>> 
>>> This is incorrectly stated. Also on the initial import it will fail, not
>>> just on subsequent imports.
>>> 
>>> piet$ python
>>> Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39)
>>> [GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
>>> Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg import _impl
>>> 
>>> _impl # this is from a print statement in _impl to show that it did import
>>> Traceback (most recent call last):
>>> ? File "<stdin>", line 1, in <module>
>>> ImportError: cannot import name _impl
>>> 

>r> Well, since __init__.py is executed first, I would regard it as
>r> causing the initial (successful) import, and yours being the
>r> subsequent one, so that the "initial" import does not fail, the
>r> subsequent one does. Wording aside, though, I think we are on the same
>r> page here.

I was talking about the 'from pkg import _impl' statements because I
thought that's what we were talking about. Of course this does an
implicit 'import pkg' first, but that doesn't fail. In your OP you were
also talking about `from pkg import mod' imports and said that the
subsequent ones of these fails. I noticed that also the first one of
these would fail.

>>> 
>>> According to the documentation
>>> <http://docs.python.org/library/functions.html#__import__> the statement
>>> from pkg import _impl
>>> 
>>> _temp = __import__('pkg', globals(), locals(), ['_impl'], -1)
>>> _impl = _temp._impl
>>> 
>>> This fails because _temp (the imported module) doesn't have a binding
>>> for _impl because you deleted it.

>r> But supposing we hadn't deleted it, and __init__.py didn't import
>r> _impl, there would still be no binding. Yet the importer would still
>r> import and make the module available (presumably it "knows" to do this
>r> since it was not already in sys.modules). The question really is that
>r> since in our example pkg._impl is still in sys.modules, why won't the
>r> importer add it to the pkg namespace again as it previous had? I would
>r> imagine this is either by design, or is a case that was never
>r> considered.

Yes, that is also something I don't understand.

>>> for _impl because you deleted it. By the way, if you have a `normal'
>>> package that doesn't do anything with the name _impl, after the import
>>> the pkg module namespace will have got a binding for _impl although it is not
>>> in your code. It will have been put there by the import code.

>r> Yes, this was noted further down in the original post with an example.

Sorry, I missed that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From bazwal at ftml.net  Sun Jul 26 12:22:53 2009
From: bazwal at ftml.net (Baz Walter)
Date: Sun, 26 Jul 2009 17:22:53 +0100
Subject: pyc files not automatically compiled on import
Message-ID: <4A6C82DD.8020005@ftml.net>

hello

i thought that python automatically compiled pyc files after a module is 
successfully imported. what could prevent this happening?


Python 2.6.1 (r261:67515, Apr 12 2009, 03:51:25)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
 >>> import os
 >>> os.mkdir('/home/baz/tmp/foo')
 >>> os.chdir('/home/baz/tmp/foo')
 >>> f = open('foo.py', 'w')
 >>> f.write('print "hello world"\n')
 >>> f.close()
 >>> os.listdir('.')
['foo.py']
 >>> import foo
hello world
 >>> os.listdir('.') # why no pyc file?
['foo.py']
 >>> import py_compile
 >>> py_compile.compile('foo.py')
 >>> os.listdir('.')
['foo.py', 'foo.pyc']



From fuzzyman at gmail.com  Sun Jul 26 12:44:14 2009
From: fuzzyman at gmail.com (Fuzzyman)
Date: Sun, 26 Jul 2009 09:44:14 -0700 (PDT)
Subject: pyc files not automatically compiled on import
References: <mailman.3739.1248625343.8015.python-list@python.org>
Message-ID: <d6c8d04c-ceef-48ad-a7fb-8be52e0a8a4b@s15g2000yqs.googlegroups.com>

On Jul 26, 5:22?pm, Baz Walter <baz... at ftml.net> wrote:
> hello
>
> i thought that python automatically compiled pyc files after a module is
> successfully imported. what could prevent this happening?
>
> Python 2.6.1 (r261:67515, Apr 12 2009, 03:51:25)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> ?>>> import os
> ?>>> os.mkdir('/home/baz/tmp/foo')
> ?>>> os.chdir('/home/baz/tmp/foo')
> ?>>> f = open('foo.py', 'w')
> ?>>> f.write('print "hello world"\n')
> ?>>> f.close()
> ?>>> os.listdir('.')
> ['foo.py']
> ?>>> import foo
> hello world
> ?>>> os.listdir('.') # why no pyc file?
> ['foo.py']
> ?>>> import py_compile
> ?>>> py_compile.compile('foo.py')
> ?>>> os.listdir('.')
> ['foo.py', 'foo.pyc']

Works for me I'm afraid (Mac OS X and Python 2.6).

Michael Foord
--
http://www.ironpythoninaction.com/


From roy at panix.com  Sun Jul 26 12:53:59 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 26 Jul 2009 12:53:59 -0400
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
Message-ID: <roy-51AEF5.12535926072009@news.panix.com>

In article 
<148abf0f-c9e4-4156-8f16-e4e5615d350b at s6g2000vbp.googlegroups.com>,
 Paul Barry <pauljbarry3 at gmail.com> wrote:

> host = '127.0.0.1'           # Bind to all interfaces

This threw me off the track for a little while.  The comment is wrong!  
You're not binding to all interfaces, you're binding specifically to the 
loopback interface.  For what you're doing, it's fine, but the comment is 
still wrong.

It's also a little weird that the example uses connect() and sendall().  
Those are TCP-ish type constructs.  They work with UDP sockets, but using 
them sort of obscures the fundamental datagram nature of UDP.

Well, enough of that.  The real problem seems to be right here:

> print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> while 1:
>     buf = s.recvfrom(2048)
>     sys.stdout.write(buf[0])

Try adding sys.stdout.flush(), and it should work.  Or change it to print.

I've never seen this book, but if this code really is verbatim from the 
book, I'm not very impressed.


From __peter__ at web.de  Sun Jul 26 13:07:30 2009
From: __peter__ at web.de (Peter Otten)
Date: Sun, 26 Jul 2009 19:07:30 +0200
Subject: pyc files not automatically compiled on import
References: <mailman.3739.1248625343.8015.python-list@python.org>
Message-ID: <h4i2fu$4p7$00$1@news.t-online.com>

Baz Walter wrote:

> i thought that python automatically compiled pyc files after a module is
> successfully imported. what could prevent this happening?
> 
> 
> Python 2.6.1 (r261:67515, Apr 12 2009, 03:51:25)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>  >>> import os
>  >>> os.mkdir('/home/baz/tmp/foo')
>  >>> os.chdir('/home/baz/tmp/foo')
>  >>> f = open('foo.py', 'w')
>  >>> f.write('print "hello world"\n')
>  >>> f.close()
>  >>> os.listdir('.')
> ['foo.py']
>  >>> import foo
> hello world
>  >>> os.listdir('.') # why no pyc file?
> ['foo.py']
>  >>> import py_compile
>  >>> py_compile.compile('foo.py')
>  >>> os.listdir('.')
> ['foo.py', 'foo.pyc']

You did not set the PYTHONDONTWRITEBYTECODE environment variable in a former 
life, or did you?



From Tom.sully at gmx.com  Sun Jul 26 13:13:44 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 10:13:44 -0700 (PDT)
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org> 
	<7d2nfnF29tk6fU1@mid.uni-berlin.de>
Message-ID: <cfa3dd46-8938-49dd-acb9-8ba6c9a6420b@o6g2000yqj.googlegroups.com>

Sorry for not providing enough information - and Rhodri, for sending
my second message I used the GMX webmail client rather than my usual
Linux client as I was testing it on windows. That must have screwed it
up, I need to download Thunderbird on Mozzila.

The thing that was messing it up was that the endlines are handled
differently on each each OS, so I changed the code to strip the
endlines to be:

    if os.name == "nt":
        s = sauce.rstrip("\r\n")
    else:
        s = sauce.replace("\n", "")

This works fine now, (os.name returns nt on windows and posix on
linux)
Thanks for the help, and sorry for slow response and lack of detail,
I'm still trying to get used to this usenet thing :P

--
print "Tom"


From qauzzix at gmail.com  Sun Jul 26 13:48:27 2009
From: qauzzix at gmail.com (Qauzzix)
Date: Sun, 26 Jul 2009 10:48:27 -0700 (PDT)
Subject: How do I generate dia diagrams from python source code?
References: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
	<mailman.3705.1248510681.8015.python-list@python.org>
Message-ID: <b0b7be72-7003-45d5-b8a5-1e74658b4901@32g2000yqj.googlegroups.com>

On Jul 25, 8:31?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Fri, 24 Jul 2009 17:52:47 -0300, Qauzzix <qauz... at gmail.com> escribi?:
>
> > Since I have been usingdiato make my UML diagrams. I also found an
> > util named dia2code that generates python code fromdiadiagram. Now
> > that I have that option I really want to find a way to generatedia
> > diagram from existing code and/or maintain my diagrams.
>
> > I have been googling ?like crazy trying to find a way but with no
> > luck. Anyone here know how to do this?
>
> SPE does that:http://pythonide.stani.be/
>
> --
> Gabriel Genellina

I think You are misunderstanding my question. I downloaded SPE and I
have been trying it out. It has an UML featus but in no way I can see
can I export it to be used by DIA the diagram editor. I could export
it as an image, nothing more. There exists many apps for extracting
UML diagrams from Python source but I need it to conform with DIA.


From gallium.arsenide at gmail.com  Sun Jul 26 13:54:52 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Sun, 26 Jul 2009 10:54:52 -0700 (PDT)
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org> 
	<7d2nfnF29tk6fU1@mid.uni-berlin.de>
	<cfa3dd46-8938-49dd-acb9-8ba6c9a6420b@o6g2000yqj.googlegroups.com>
Message-ID: <2abd5ecb-6fed-4763-9563-2caf63ca3c15@r25g2000vbn.googlegroups.com>

On Jul 26, 1:13?pm, Tom <Tom.su... at gmx.com> wrote:
> The thing that was messing it up was that the endlines are handled
> differently on each each OS, so I changed the code to strip the
> endlines to be:
>
> ? ? if os.name == "nt":
> ? ? ? ? s = sauce.rstrip("\r\n")
> ? ? else:
> ? ? ? ? s = sauce.replace("\n", "")

Well, this is doing two different things.  When os.name is 'nt', you
are getting rid of all *trailing* CRLFs.  Otherwise, you are getting
rid of all LFs *anywhere in the string*.  (Even if it so happens sauce
will only ever have LFs at the end, it's still better to use the
method that is closest to your intended meaning.)

Personally, I prefer using sauce.rstrip() with no parameters (one of
the suggestions Rhodri mentioned) if it's not important to preserve
trailing spaces, since this will work regardless of end-of-line style
(and typically, trailing spaces, tabs, etc. are undesirable anyway).

John


From aahz at pythoncraft.com  Sun Jul 26 13:56:54 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 10:56:54 -0700
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org>
Message-ID: <h4i5d6$mql$1@panix3.panix.com>

In article <mailman.3714.1248551656.8015.python-list at python.org>,
Tom  <tom.sully at gmx.com> wrote:
>
>I have an annoying problem. While I mainly use Linux when I distribute
>this program to friends and on the internet, it'll get used on Windows.
>So, I tested my python program on my Windows Vista dual boot, running
>the same version of python (2.6) as my Linux, and got an error at the
>following code.
>
>s = sauce.replace("\n", "")
>
>Sauce is a string, read from a file, that I need to remove newlines
>from. This code works fine in Linux, but not in Windows. rstrip("\n")
>won't work for me, so anybody know how to get this working on Windows?

Use open(fname, 'U')
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From martin at v.loewis.de  Sun Jul 26 14:03:39 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 20:03:39 +0200
Subject: C-API, tp_dictoffset vs tp_members
In-Reply-To: <7d2mu7F27a9tbU1@mid.uni-berlin.de>
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
	<7d2mu7F27a9tbU1@mid.uni-berlin.de>
Message-ID: <4a6c9a7c$0$12532$9b622d9e@news.freenet.de>

>>> I have a predefined set of members, some of which are optional.
>> Having optional fields is also a good reason.
> 
> What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then?

Right - this works for optional objects. However, it can't possibly
work for any of the other fields.

>  I would
>  have though that the former describes an optional field, because the
>  behaviour of accessing it when it is NULL is the same as accessing a
>  nonexistent field. However, I see that it still appears in the dir()
>  output even if it is NULL, so it seems I'm misunderstanding this.

I suppose that's because there will still be a descriptor for the field
in the class.

> The 'example_attribute' can be accessed, but it is not visible in the
> dir() output. The code for this is below.

I see. So you do need a tp_members list:

static PyMemberDef example_members[] = {
     {"__dict__", T_OBJECT, offsetof(Example, dict), READONLY},
     {0}
};

Perhaps dir() should know about tp_dictoffset, but alas, it doesn't.

Regards,
Martin


From vivainio at gmail.com  Sun Jul 26 14:20:59 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Sun, 26 Jul 2009 11:20:59 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
	<slrnh6hfrp.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <69c8f3be-cc84-48e5-9969-ef9e87836094@e27g2000yqm.googlegroups.com>

On Jul 23, 11:29?pm, Nick Craig-Wood <n... at craig-wood.com> wrote:

> > ?The syntax would be something like:
>
> > ?def work():
>
> > ? ?showstatus("building")
> > ? ?r = yield runshell("make")
> > ? ?showstatus("installing")
> > ? ?r = yield runshell("make install")
> > ? ?showstatus("Success")
>
> > ?mygui.startwork(work)
> > ?# returns immediately, runs work() gradually in the background.
>
> > ?The catch is that showstatus() would need to be run in the mainloop,
> > ?so running the whole thing in a thread is a no-go.
>
> > ?I imagine runshell() would be implemented in terms of QProcess, or
> > ?subprocess.Popen/os.system and a worker thread.
>
> > ?Anyone done this already, or do I have to roll my own?
>
> You might want to look at twisted, in particular
>
> ?http://twistedmatrix.com/trac/wiki/DeferredGenerator

Indeed, DeferredGenerator looks pretty much what I'm interested in,
thanks for the pointer. Unfortunately, it has the big Twisted
dependency. That's probably not a showstopper, but Twisted requires a
degree of buy-in when something smaller would do.


From santhosh.vkumar at gmail.com  Sun Jul 26 14:22:42 2009
From: santhosh.vkumar at gmail.com (Santhosh Kumar)
Date: Sun, 26 Jul 2009 23:52:42 +0530
Subject: Itext for Python
Message-ID: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com>

Hi all,           One of my cousin  suggested me to do a IText
PDF converter for python. Actually I heard that there is
no separate IText converter either we have to go for jython or GCJ with
wrapper. Instead of wrapping, my plan is to create a separate module with
Python and I am thinking of doing this in as my final year project also.
Kindly give me your suggestion.

        With anticipation,

SanthoshVKumar.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090726/f2162d8f/attachment.html>

From nagle at animats.com  Sun Jul 26 14:24:48 2009
From: nagle at animats.com (John Nagle)
Date: Sun, 26 Jul 2009 11:24:48 -0700
Subject: Help understanding the decisions *behind* python? - immutable
	objects
In-Reply-To: <9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
Message-ID: <4a6c9ec0$0$1636$742ec2ed@news.sonic.net>

Beni Cherniavsky wrote:
> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
> wrote:
>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>
>>> My guess is that it was probably for optimization reasons long ago.
>>> I've never heard a *good* reason why Python needs both.
>> The good reason is the immutability, which lets you use
>> a tuple as a dict key.  
>>
> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
> wrote:
>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>
>>> My guess is that it was probably for optimization reasons long ago.
>>> I've never heard a *good* reason why Python needs both.
>> The good reason is the immutability, which lets you use
>> a tuple as a dict key.
>>
> The *technical* reason is immutability for dict keys.
> Dict could allow mutable objects as keys by comparing *by value*,
> making a copy on insertion and hashing the current value on lookup.
> Prior art: the 2.3 sets module allows mutable Sets as elements in
> Sets, by making ImmutableSet copies on insertion, and hashing Sets as
> if they are temporarily immutable on lookup.
> 
> This inspired PEP 351 and ambitious proposals to expand the approach
> to all Python with a copy-on-write scheme.  But these ideas were
> rejected, and the 2.4 builtin sets only allow frozenset elements.
> Half the reason is technical: copy-on-write and harder than it sounds,
> and without it you pay a performance price.
> 
> But the deeper reason is style: immutable types are convenient!
> The allow a pure-functional style of code, which can be simpler.
> Of course, sometimes an imperative style is simpler.  Depends on the
> problem.

     An interesting issue is Python objects, which are always mutable.
A "dict" of Python objects is allowed, but doesn't consider
the contents of the objects, just their identity (address). Only
built-in types are immutable; one cannot create a class of immutable objects.
So things like "frozenset" had to be built into the language.
A tuple is really a frozen list.  Arguably, frozen objects
should have been a general concept.  Conceptually, they're
simple - once "__init__" has run, there can be no more changes
to fields of the object.

     Compare the C++ approach, where you can have a "map" of
any object that defines the "<" operator.  Python has
"__cmp__" for objects, but built-in dictionaries don't use it.
Of course, one could create a "map" class in Python that
uses "__cmp__", which would allow dictionary-type operations
on arbitrary objects.

     There are some interesting uses for immutable objects in
multithreaded programs.  They can be shared between threads
without locking.  If it weren't for the infamous Global
Interpreter Lock, which basically limits Python programs to using
one CPU at a time, Python would have to deal with locking
in a more advanced way.  A system where immutable objects
can be shared and passed between threads, and mutable objects
must be "synchronized" (in the Java sense) to be shared would
be useful.

				John Nagle


From vivainio at gmail.com  Sun Jul 26 14:32:11 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Sun, 26 Jul 2009 11:32:11 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
	<4a65f0d8$0$1599$742ec2ed@news.sonic.net>
Message-ID: <ed3da964-c58e-498a-b301-e54980e54101@a26g2000yqn.googlegroups.com>

Apologies for the long subject line, here it is again:

"Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() that
doesn't block gui event loops"

On Jul 21, 7:48?pm, John Nagle <na... at animats.com> wrote:

> > The idea:
>
> > To run functions that execute a series of system commands without
> > blocking the ui, *and* without adding state machine logic.
>
> ? ? At some level, there's going to be state machine logic.
> You need interlocking so that the user can't initiate
> simultaneous conflicting background operations from the GUI.

This belongs to the "I don't care" category, as you'd expect to have
only one operation like this on the flight at one time. The idea is to
allow making simple scripts that you execute from the gui, that *may*
need to access the gui objects at one point or another (so execution
has to happen in the main thread most of the time - apart from
blocking, long operations).


> ? ? The usual solution is to run the background operations
> in another thread, and have them put events on a queue
> read by the GUI task.

Yeah, and the receiving end of the "queue" here would be the same
block of statements that launched the request - that is, I want to
avoid having to create handler functions, and keep the program from
linear.


> ? ? You also have to work out how to cancel background operations,
> if they're going to be as big as a "make".

I think that is easy to accomplish with generators, provided that you
can let the long-lasting operation run to completion - just close()
the generator. If the long lasting computation was in a subprocess,
rather than a thread, it could be interrupted in a cleaner fashion
even.


From drobinow at gmail.com  Sun Jul 26 15:26:46 2009
From: drobinow at gmail.com (David Robinow)
Date: Sun, 26 Jul 2009 14:26:46 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4gnmr$8cl$1@news.eternal-september.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
Message-ID: <4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>

> This doesn't mean they're on the same level - in fact, if you read carefully
> you'll see my original post said as much: python attracted average
> programmers; php attracted mediocre programmers and even some
> non-programmers, which means that php is clearly a lesser language than
> python.
 I'm a mediocre programmer. Does this mean I should switch to PHP?


From bazwal at ftml.net  Sun Jul 26 15:30:12 2009
From: bazwal at ftml.net (Baz Walter)
Date: Sun, 26 Jul 2009 20:30:12 +0100
Subject: pyc files not automatically compiled on import
In-Reply-To: <h4i2fu$4p7$00$1@news.t-online.com>
References: <mailman.3739.1248625343.8015.python-list@python.org>
	<h4i2fu$4p7$00$1@news.t-online.com>
Message-ID: <4A6CAEC4.7020300@ftml.net>

Peter Otten wrote:
> You did not set the PYTHONDONTWRITEBYTECODE environment variable in a former 
> life, or did you?

thanks peter

no i didn't, but i've just discovered a script in /etc/profile.d that 
did. now i'll have to try to find out how that script got in there :-|



From dotancohen at gmail.com  Sun Jul 26 15:34:52 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Sun, 26 Jul 2009 22:34:52 +0300
Subject: Looking for a dream language: sounds like Python to me.
Message-ID: <880dece00907261234x684547f4g5272b211379a7ba1@mail.gmail.com>

Referring to this article:
http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/

The author, who is specifically looking for math-related functions, writes:
"""
The dream algorithm R&D tool would be similar to Matlab or Mathematica
but could be compiled to fast, efficient binaries similar to ANSI C
and would be available for all platforms. An integrated GUI builder
similar to Visual Basic and integrated network support would be
helpful.
"""

It looks to me like he is looking for Python.

-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From doomster at knuut.de  Sun Jul 26 15:39:17 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Sun, 26 Jul 2009 21:39:17 +0200
Subject: C-API, tp_dictoffset vs tp_members
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
	<7d2mu7F27a9tbU1@mid.uni-berlin.de>
	<4a6c9a7c$0$12532$9b622d9e@news.freenet.de>
Message-ID: <7d3pnaF29o57gU1@mid.uni-berlin.de>

"Martin v. L?wis" wrote:
>>>> I have a predefined set of members, some of which are optional.
>>> Having optional fields is also a good reason.
>> 
>> What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then?
> 
> Right - this works for optional objects. However, it can't possibly
> work for any of the other fields.

I have two members, one T_OBJECT and one T_OBJECT_EX. Both are NULL and both 
still appear in the dir() output. For one, accessing it returns 'None', for 
the other it raises an exception. I would have expected an element that is 
not accessible, not even 'None', to also not be visible in dir().

>>  I would have thought that the former describes an optional field,
>>  because the behaviour of accessing it when it is NULL is the same
>>  as accessing a nonexistent field. However, I see that it still
>>  appears in the dir() output even if it is NULL, so it seems I'm
>>  misunderstanding this.
> 
> I suppose that's because there will still be a descriptor for the
> field in the class.

So is that intentional or is it dir() that could be improved there? Should I 
file a bugreport?


Thanks for the tip with __dict__ in tp_members, that does the job!

Uli




From pauljbarry3 at gmail.com  Sun Jul 26 15:40:39 2009
From: pauljbarry3 at gmail.com (Paul Barry)
Date: Sun, 26 Jul 2009 12:40:39 -0700 (PDT)
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<roy-51AEF5.12535926072009@news.panix.com>
Message-ID: <2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a@p23g2000vbl.googlegroups.com>

On Jul 26, 12:53?pm, Roy Smith <r... at panix.com> wrote:
> In article
> <148abf0f-c9e4-4156-8f16-e4e5615d3... at s6g2000vbp.googlegroups.com>,
> ?Paul Barry <pauljbar... at gmail.com> wrote:
>
> > host = '127.0.0.1' ? ? ? ? ? # Bind to all interfaces
>
> This threw me off the track for a little while. ?The comment is wrong! ?
> You're not binding to all interfaces, you're binding specifically to the
> loopback interface. ?For what you're doing, it's fine, but the comment is
> still wrong.

You are right.  The example in the book actually has

host = ''

So the comment is correct.  In trying to debug what was going on, I
put 127.0.0.1 to see if that had something to do with it, which it
didn't.

>
> It's also a little weird that the example uses connect() and sendall(). ?
> Those are TCP-ish type constructs. ?They work with UDP sockets, but using
> them sort of obscures the fundamental datagram nature of UDP.
>
> Well, enough of that. ?The real problem seems to be right here:
>
> > print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> > while 1:
> > ? ? buf = s.recvfrom(2048)
> > ? ? sys.stdout.write(buf[0])
>
> Try adding sys.stdout.flush(), and it should work. ?Or change it to print.
>

Yes, that did the trick, thanks.  I should have thought of that, if I
would have just printed something after the recvfrom line I would have
realized it was no longer blocking and the problem was with getting
the client to print the data to stdout, not with getting a response
from the server.

> I've never seen this book, but if this code really is verbatim from the
> book, I'm not very impressed.

I like the book so far.  It's a little verbose, but I think that's
because he's trying to teach the concepts, rather than the write it
how you actually would in production.  In this case, I think he's
trying to illustrate how the UDP example compares to the TCP example
from the previous section, which is why he choose to keep the methods
the same.

But why not use

    print buf[0]

instead of

    sys.stdin.write(buf[0])

that much, I don't know.



From pauljbarry3 at gmail.com  Sun Jul 26 15:42:32 2009
From: pauljbarry3 at gmail.com (Paul Barry)
Date: Sun, 26 Jul 2009 12:42:32 -0700 (PDT)
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<mailman.3736.1248620831.8015.python-list@python.org>
Message-ID: <87ff9f36-30cb-4982-9730-7dcee491c0de@l2g2000vba.googlegroups.com>

On Jul 26, 11:07?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Paul Barry wrote:
> > I'm trying to get one of the examples from Foundation of Python
> > Network Programming to work. ?Specifically this is the UDP example
> > from Ch 3. ?First there is the server:
>
> > #!/usr/bin/env python
> > # UDP Echo Server - Chapter 3 - udpechoserver.py
> > import socket, traceback, time
>
> > host = '127.0.0.1' ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? # Bind to all
> > interfaces
> > port = 51423
>
> > s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> > s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
> > s.bind((host, port))
>
> > while 1:
> > ? ? try:
> > ? ? ? ? message, address = s.recvfrom(8192)
> > ? ? ? ? print "Got message '%s' from %s" % (message, address)
>
> > ? ? ? ? # Echo it back
> > ? ? ? ? s.sendto(message, address)
> > ? ? ? ? print "Sent response to '%s'" % (address,)
>
> > ? ? except (KeyboardInterrupt, SystemExit):
> > ? ? ? ? raise
> > ? ? except:
> > ? ? ? ? traceback.print_exc()
>
> > Next I have a client written in Ruby, which works. ?I am posting thing
> > not to start a Ruby/Python flame war, but to simply prove that the
> > server works and there are no weird networking issues that would
> > prevent the Python client from working. ?The Ruby code is:
>
> > #!/usr/bin/env ruby
> > require 'socket'
>
> > socket = UDPSocket.new
> > socket.connect ARGV[0], ARGV[1]
>
> > puts "Enter data to transmit: "
> > data = STDIN.gets.chomp
>
> > socket.send data, 0
> > puts "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
>
> > loop do
> > ? buf = socket.recvfrom(2048)
> > ? puts buf.first
> > end
>
> > When I start the server and run that, the output looks like this:
>
> > $ ch02/udp.rb 127.0.0.1 51423
> > Enter data to transmit:
> > foobar
> > Looking for replies; press Ctrl-C or Ctrl-Break to stop.
> > foobar
>
> > Now, when I try the python example:
>
> > #!/usr/bin/env python
> > # UDP Example - Chapter 2 - udp.py
>
> > import socket, sys
>
> > host = sys.argv[1]
> > textport = sys.argv[2]
>
> > s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> > try:
> > ? ? port = int(textport)
> > except ValueError:
> > ? ? # That didn't work. ?Look it up instead.
> > ? ? port = socket.getservbyname(textport, 'udp')
>
> > s.connect((host, port))
> > print "Enter data to transmit: "
> > data = sys.stdin.readline().strip()
> > s.sendall(data)
>
> > print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> > while 1:
> > ? ? buf = s.recvfrom(2048)
> > ? ? sys.stdout.write(buf[0])
>
> > I don't ever get a response:
>
> > $ ch02/udp.py 127.0.0.1 51423
> > Enter data to transmit:
> > foobar
> > Looking for replies; press Ctrl-C or Ctrl-Break to stop.
>
> > The server sees the message and says it has sent a reply:
>
> > Got message 'foobar' from ('127.0.0.1', 49623)
> > Sent response to '('127.0.0.1', 49623)'
>
> > Any ideas as to why this doesn't work?
>
> It works on my PC (Python 2.6.2, Windows XP Pro, service pack 3).

Doesn't work on a Mac with Python 2.5.1 or 2.6.2 unless you flush
stdout or change it to print.  Not sure why it would work on one
platform and not the other.


From Tom.sully at gmx.com  Sun Jul 26 15:45:10 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 12:45:10 -0700 (PDT)
Subject: Globalize all variables in function without knowing names.
Message-ID: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>

Does anyknow know how to do this? The reason I'm asking is because I'm
trying to make a mini-programming language for fun, and need to work
with variables.

The user types 'set NAME "DATA" ' or whatever else the variable is
going to be called/contain.

I have:
def variablework(varname, varset):
    exec("global "+varname) #DEFUNCT
    vars()[varname] = varset
    exec("print "+varname)   #Debug purposes only

This sets the variable (varname is the name of the variable, and
varset is the data for it to contain) all fine and dandy, but it is
local, and after some googling I realised that you can't globalised
variables using exec. So I think the next best thing would be to find
a way to globalize every variable in the function, but I don't know
how to do this. If there isn't a way of doing this, can someone
suggest another way of globalizing variable without knowing their
names?


From roy at panix.com  Sun Jul 26 16:31:43 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 26 Jul 2009 16:31:43 -0400
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<roy-51AEF5.12535926072009@news.panix.com>
	<2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a@p23g2000vbl.googlegroups.com>
Message-ID: <roy-21371D.16314326072009@news.panix.com>

In article 
<2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a at p23g2000vbl.googlegroups.com>,
 Paul Barry <pauljbarry3 at gmail.com> wrote:

> In this case, I think he's trying to illustrate how the UDP example 
> compares to the TCP example from the previous section, which is why he 
> choose to keep the methods the same.


I suppose, but I still think that's a confusing way to teach the 
differences between UDP and TCP.  The fundamental differences are:

1) TCP makes sure what you send gets there (for reasonably large values of 
"makes sure").  UDP just tosses stuff out onto the network and hopes for 
the best.

2) TCP is connection-oriented.  Connections must be explicitly set up 
before any data can flow, and once two sockets are connected, they can 
never be disconnected (short of tearing down the connection and starting 
again with two new sockets).  With UPD, every time you send data, you have 
to specify where it's going, and a given socket can be talking to many 
different remote endpoints on a packet-by-packet basis.

3) TCP is a stream protocol, which hides record boundaries; it is free to 
combine and/or split up your data into whatever packet boundaries it wants, 
and there is no way for the receiving end to discover where the boundaries 
are.  UDP, on the other hand, honors record boundaries; there is a 
one-to-one correspondence between each write (send, sendto) call at one and 
each read (recv, recvfrom) call at the other.

It's difficult to demonstrate #1 in a simple example, so I'll skip that.  
But, #2 and #3 are easy.

The example you gave uses connect() on a UDP socket.  That's not pointing 
out the differences between UDP and TCP, that's hiding them behind a 
strange corner of the API.  There really is no connection set up when you 
do connect() on a UDP socket; it's just a way of saying, "From now on, I'm 
going to skip telling you the destination of each individual datagram.  
Just use this destination from now on".  It saves moving a bit of data 
around, but it's not fundamentally a connection.

As for the stream/datagram distinction, sendall() is very much a stream 
creature.  It says, "Just keep banging out packets until you've managed to 
transmit the whole buffer".  That only makes sense in an environment where 
packet boundaries are meaningless.  Using it with UDP is sort of like 
saying, "Use as many packets as it takes, as long as that number is one".  
It's not not a concept that makes sense in a datagram world.  That it works 
at all on UDP is (IHMO) a mis-guided attempt at interface uniformity.

If I were writing an example on how to use UDP, I would leave out the 
connect() call, and use sendto() instead of sendall().  Once the student 
has those down, that's the time to talk about weird corner cases like how 
connect() and sendall() can be twisted to work with UDP sockets.  Or maybe 
not even bother.


From Tom.sully at gmx.com  Sun Jul 26 16:57:02 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 13:57:02 -0700 (PDT)
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org> 
	<7d2nfnF29tk6fU1@mid.uni-berlin.de>
	<cfa3dd46-8938-49dd-acb9-8ba6c9a6420b@o6g2000yqj.googlegroups.com>
	<2abd5ecb-6fed-4763-9563-2caf63ca3c15@r25g2000vbn.googlegroups.com>
Message-ID: <d8b0cd0b-f96f-4a17-8240-50f8fb76a592@m11g2000yqh.googlegroups.com>

> (Even if it so happens sauce
> will only ever have LFs at the end, it's still better to use the
> method that is closest to your intended meaning.)

Oh, you're right. I'll change that now. I suppose removing all
endlines will be better, incase, somehow, endlines in the middle of
the line arrises.

> if it's not important to preserve trailing spaces

The way I parse the file currently splits away all whitespace later
on. While I could change this, I have a nice system worked out and my
code is working, so it's not top priority.


From python at mrabarnett.plus.com  Sun Jul 26 16:59:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 26 Jul 2009 21:59:42 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<4a6905b0$0$27110$a729d347@news.telepac.pt>	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>	<h4ctjv$bhj$1@news.eternal-september.org>	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
Message-ID: <4A6CC3BE.6060806@mrabarnett.plus.com>

David Robinow wrote:
>> This doesn't mean they're on the same level - in fact, if you read carefully
>> you'll see my original post said as much: python attracted average
>> programmers; php attracted mediocre programmers and even some
>> non-programmers, which means that php is clearly a lesser language than
>> python.
>  I'm a mediocre programmer. Does this mean I should switch to PHP?

If you're a mediocre programmer who knows you're mediocre, but wants to
improve and is willing to learn, then stick with Python. You'll get
better. :-)


From roy at panix.com  Sun Jul 26 17:04:23 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 26 Jul 2009 17:04:23 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
Message-ID: <roy-F3FA5C.17042326072009@news.panix.com>

In article <h4gnmr$8cl$1 at news.eternal-september.org>,
 Raffael Cavallaro <raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com> 
 wrote:

> php is clearly a lesser language than python.

I'm as much of a Python bigot as anybody.  Likewise, I put down php for all 
the sorts of theoretical reasons people have been putting it down.  Not to 
mention that it looks like Perl, which is enough to make anybody go 
screaming in the other direction.

However, it's hard to argue with success.  A ton of very useful software 
has been written in php (including MediaWiki, which drives Wikipedia).  One 
needs to have a very highly developed sense of theoretical purity to look 
down their noses at the language that drives one of the highest volume web 
sites on the planet.


From gagsl-py2 at yahoo.com.ar  Sun Jul 26 17:06:48 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 26 Jul 2009 18:06:48 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
	<h4av5n$p1l$1@panix3.panix.com>
	<mailman.3648.1248429993.8015.python-list@python.org>
	<h4htk2$fmb$1@panix3.panix.com>
Message-ID: <op.uxo0xmydx6zn5v@gabriel.sleipnir-bsas>

En Sun, 26 Jul 2009 12:44:02 -0300, Aahz <aahz at pythoncraft.com> escribi?:
> In article <mailman.3648.1248429993.8015.python-list at python.org>,
> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>> En Thu, 23 Jul 2009 21:27:35 -0300, Aahz <aahz at pythoncraft.com>  
>> escribi?:
>>> In article <mailman.3561.1248307942.8015.python-list at python.org>,
>>> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>>>>
>>>> NLMPI
>>>
>>> What?
>>
>> IHNFI
>
> What?  Abbreviations are fine, but if someone asks you about one, it
> would be nice to just expand it instead of replying with another
> abbreviation.

Ok, if you insist...

NLMPI = Ni La M?s Puta Idea.
IHNFI = I Have No Fucking Idea.

-- 
Gabriel Genellina



From martin at v.loewis.de  Sun Jul 26 17:24:43 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 23:24:43 +0200
Subject: C-API, tp_dictoffset vs tp_members
In-Reply-To: <7d3pnaF29o57gU1@mid.uni-berlin.de>
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
	<7d2mu7F27a9tbU1@mid.uni-berlin.de>
	<4a6c9a7c$0$12532$9b622d9e@news.freenet.de>
	<7d3pnaF29o57gU1@mid.uni-berlin.de>
Message-ID: <4A6CC99B.4070406@v.loewis.de>

>>>>> I have a predefined set of members, some of which are optional.
>>>> Having optional fields is also a good reason.
>>> What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then?
>> Right - this works for optional objects. However, it can't possibly
>> work for any of the other fields.
> 
> I have two members, one T_OBJECT and one T_OBJECT_EX. Both are NULL and both 
> still appear in the dir() output. For one, accessing it returns 'None', for 
> the other it raises an exception. I would have expected an element that is 
> not accessible, not even 'None', to also not be visible in dir().

I understood your expectation already. I maintain my theory that it
shows up because there is a descriptor on the class.

>> I suppose that's because there will still be a descriptor for the
>> field in the class.
> 
> So is that intentional or is it dir() that could be improved there? 

It's probably both.

> Should I file a bugreport?

Only if you can provide a patch also. My guess is that when you have
the patch completed, you might realize that it is not an improvement,
despite achieving what you wanted to achieve.

Regards,
Martin


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Sun Jul 26 17:41:31 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Sun, 26 Jul 2009 17:41:31 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<roy-F3FA5C.17042326072009@news.panix.com>
Message-ID: <h4iivd$o3q$1@news.eternal-september.org>

On 2009-07-26 17:04:23 -0400, Roy Smith <roy at panix.com> said:

> One
> needs to have a very highly developed sense of theoretical purity to look
> down their noses at the language that drives one of the highest volume web
> sites on the planet.

It's nothing to do with theoretical purity and everything to do with 
practicality. php has a limited range of utility. Within that range, 
it's clearly quite useful. Python is useful for a greater range of 
tasks which makes it a more generally useful (and in this sense, 
better) language.


-- 
Raffael Cavallaro



From devent at deventm.org  Sun Jul 26 17:49:58 2009
From: devent at deventm.org (Erwin Mueller)
Date: Mon, 27 Jul 2009 07:49:58 +1000
Subject: How to comment constant values?
Message-ID: <200907270749.58845.devent@deventm.org>

Hello, I'm new to Python (using it for two months) and I wonder how can I 
comment the const. values with the doc-strings. I.e. if I have code:

>FRACTION_MIN = 1
>FRACTION_MAX = 10
>
>class Fraction(collections.MutableSequence):
>    '''Model a fraction with denominators.
>
>    It contains one ore more denomintors in a list for quick access.
>    The class is thread save, it uses a lock for all operations.
>    '''
>
>    def __init__(self):
>		# ...

The class and the methods can have doc-strings, but what about the const. 
values, FRACTION_MIN and FRACTION_MAX?

Thank you, Erwin.


From clp2 at rebertia.com  Sun Jul 26 18:06:29 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 26 Jul 2009 15:06:29 -0700
Subject: How to comment constant values?
In-Reply-To: <200907270749.58845.devent@deventm.org>
References: <200907270749.58845.devent@deventm.org>
Message-ID: <50697b2c0907261506o4c7b0a04t2e5155833f62be7e@mail.gmail.com>

On Sun, Jul 26, 2009 at 2:49 PM, Erwin Mueller<devent at deventm.org> wrote:
> Hello, I'm new to Python (using it for two months) and I wonder how can I
> comment the const. values with the doc-strings. I.e. if I have code:
>
>>FRACTION_MIN = 1
>>FRACTION_MAX = 10
>>
>>class Fraction(collections.MutableSequence):
>> ? ?'''Model a fraction with denominators.
>>
>> ? ?It contains one ore more denomintors in a list for quick access.
>> ? ?The class is thread save, it uses a lock for all operations.
>> ? ?'''
>>
>> ? ?def __init__(self):
>> ? ? ? ? ? ? ? # ...
>
> The class and the methods can have doc-strings, but what about the const.
> values, FRACTION_MIN and FRACTION_MAX?

Only modules, classes, and functions/methods can have docstrings
associated with them.
For anything else, you have to use comments; or you can mention them
in the docstrings of related things.

Cheers,
Chris
-- 
http://blog.rebertia.com


From Tom.sully at gmx.com  Sun Jul 26 18:07:08 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 15:07:08 -0700 (PDT)
Subject: Globalize all variables in function without knowing names.
References: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>
	<mailman.3748.1248642820.8015.python-list@python.org>
Message-ID: <5649dfb8-01a6-490d-bf30-b4a5206e644e@j21g2000yqe.googlegroups.com>

Ah, thanks for that Dennis. I have a system already figured out where
the user manually pre-enters all the variables into a .py file, which
obviously isn't very efficient. The language isn't going to be used
much except by me, so I suppose I'll just work with that until I look
more into dictionaries, but I'm still beginning Python, and before
that the only coding I did was a little bit of C++, so I'll wait up
for that :P


From hekevintran at gmail.com  Sun Jul 26 18:24:25 2009
From: hekevintran at gmail.com (Kevin)
Date: Sun, 26 Jul 2009 15:24:25 -0700 (PDT)
Subject: Error in compiling Python on OS X
Message-ID: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>

I am trying to compile Python 2.6.2 on Mac OS X 10.5.7.  I have Xcode
3.1.3 installed.

The error I got is below.

$ ./configure --prefix=/Users/me/python
checking for --with-universal-archs... 32-bit
checking MACHDEP... darwin
checking EXTRAPLATDIR... $(PLATMACDIRS)
checking machine type as reported by uname -m... i386
checking for --without-gcc... no
checking for gcc... gcc
checking for C compiler default output file name...
configure: error: C compiler cannot create executables
See `config.log' for more details.

Please send any ideas.


From rhodri at wildebst.demon.co.uk  Sun Jul 26 18:32:30 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 26 Jul 2009 23:32:30 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4hm7q$6g2$1@news.eternal-september.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<h4hkvn$ef6$1@panix3.panix.com>
	<h4hm7q$6g2$1@news.eternal-september.org>
Message-ID: <op.uxo4wgana8ncjz@gnudebst>

On Sun, 26 Jul 2009 14:31:06 +0100, Raffael Cavallaro  
<raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com> wrote:

> On 2009-07-26 09:16:39 -0400, aahz at pythoncraft.com (Aahz) said:
>
>> There are plenty of expert C++
>> programmers who switched to Python;
>
> "plenty" is an absolute term, not a relative term. I sincerely doubt  
> that the majority of python users were formerly *expert* C++ programmers.

Nitpicking like this doesn't help your case.

>> your thesis only applies to the
>> legions of people who found it difficult to learn C++ in the first  
>> place.
>
> No, my thesis applies to the overwhelming majority of programmers who  
> found it more difficult to *master* (i.e., not merely use) C++ as  
> opposed to mastering python. BTW, this is a *complement* not a dis;  
> python is a better language than C++ precisely because it is more  
> sensibly and elegantly designed than C++ and therefore easier to master.

It is perhaps more accurate to say that Python was designed where C++
aggregated.  C was fundamentally the wrong place to have started from,
making C++ (as distinct from the subset of C++ that is really C) harder
to learn, never mind master, than it really needed to be.

> php represents the same process but farther down the ladder, as it were.  
> There's often a tradeoff between ease of mastery and power. python hits  
> a sweet spot for many tasks and many programmers, especially as compared  
> to C++ (or even lisp, which though more powerful than python is more  
> difficult to master. lisp beats C++ on both counts imho - more powerful  
> *and* easier to master). php hits a sweet spot only in a very restricted  
> domain. Beyond that, it is clearly inferior to python which has greater  
> power, but is more difficult to master.

Fundamentally incorrect.  PHP attracted many people because of where it
lives in the web application structure -- the part of the language that
was thought about very hard.  Beyond that there's nothing much to master,
so the whole ease vs power debate is rather pointless.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From bearophileHUGS at lycos.com  Sun Jul 26 18:42:22 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Sun, 26 Jul 2009 15:42:22 -0700 (PDT)
Subject: How to comment constant values?
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
Message-ID: <5c1b5c1e-7677-4786-a026-b4825568cf5b@j32g2000yqh.googlegroups.com>

Chris Rebert:
> Only modules, classes, and functions/methods can have docstrings
> associated with them.
> For anything else, you have to use comments; or you can mention them
> in the docstrings of related things.

What about adding docstrings to other Python things, especially to
variables?

Bye,
bearophile


From deets at nospam.web.de  Sun Jul 26 18:46:01 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 00:46:01 +0200
Subject: Error in compiling Python on OS X
In-Reply-To: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>
References: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>
Message-ID: <7d44lbF29p3p7U1@mid.uni-berlin.de>

Kevin schrieb:
> I am trying to compile Python 2.6.2 on Mac OS X 10.5.7.  I have Xcode
> 3.1.3 installed.
> 
> The error I got is below.
> 
> $ ./configure --prefix=/Users/me/python

Use a framework-build.

> checking for --with-universal-archs... 32-bit
> checking MACHDEP... darwin
> checking EXTRAPLATDIR... $(PLATMACDIRS)
> checking machine type as reported by uname -m... i386
> checking for --without-gcc... no
> checking for gcc... gcc
> checking for C compiler default output file name...
> configure: error: C compiler cannot create executables
> See `config.log' for more details.
> 
> Please send any ideas.

What happens if you write a simple test.c like this:


int main() {
    return 0;
}


and compile it with gcc on the commandline? There must be a file called 
"a.out" afterwards.

diez


From deets at nospam.web.de  Sun Jul 26 18:47:08 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 00:47:08 +0200
Subject: How to comment constant values?
In-Reply-To: <mailman.3750.1248645992.8015.python-list@python.org>
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
Message-ID: <7d44ndF29p3p7U2@mid.uni-berlin.de>

Chris Rebert schrieb:
> On Sun, Jul 26, 2009 at 2:49 PM, Erwin Mueller<devent at deventm.org> wrote:
>> Hello, I'm new to Python (using it for two months) and I wonder how can I
>> comment the const. values with the doc-strings. I.e. if I have code:
>>
>>> FRACTION_MIN = 1
>>> FRACTION_MAX = 10
>>>
>>> class Fraction(collections.MutableSequence):
>>>    '''Model a fraction with denominators.
>>>
>>>    It contains one ore more denomintors in a list for quick access.
>>>    The class is thread save, it uses a lock for all operations.
>>>    '''
>>>
>>>    def __init__(self):
>>>               # ...
>> The class and the methods can have doc-strings, but what about the const.
>> values, FRACTION_MIN and FRACTION_MAX?
> 
> Only modules, classes, and functions/methods can have docstrings
> associated with them.
> For anything else, you have to use comments; or you can mention them
> in the docstrings of related things.

While this is technically true, writing docstrings to constants (module 
or classlevel) works when one uses tools such as epydoc to generate 
documentation.

Diez


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 18:49:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 22:49:33 GMT
Subject: Globalize all variables in function without knowing names.
References: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>
	<mailman.3748.1248642820.8015.python-list@python.org>
	<5649dfb8-01a6-490d-bf30-b4a5206e644e@j21g2000yqe.googlegroups.com>
Message-ID: <027cce66$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 15:07:08 -0700, Tom wrote:

> Ah, thanks for that Dennis. I have a system already figured out where
> the user manually pre-enters all the variables into a .py file, which
> obviously isn't very efficient. The language isn't going to be used much
> except by me, so I suppose I'll just work with that until I look more
> into dictionaries, but I'm still beginning Python, and before that the
> only coding I did was a little bit of C++, so I'll wait up for that :P

Dictionaries are fundamental to Python and very useful. Not learning 
about them before starting to write code is like not learning about the 
accelerator pedal before starting to drive a car. You might be able to 
get somewhere by getting out and pushing, but it will be slow and 
exhausting.

Have you done the tutorial?

http://www.python.org/doc/current/tutorial/



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 18:49:47 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 22:49:47 GMT
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<roy-51AEF5.12535926072009@news.panix.com>
	<2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a@p23g2000vbl.googlegroups.com>
Message-ID: <027cce74$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 12:40:39 -0700, Paul Barry wrote:

> On Jul 26, 12:53?pm, Roy Smith <r... at panix.com> wrote:
>> In article
>> <148abf0f-c9e4-4156-8f16-e4e5615d3... at s6g2000vbp.googlegroups.com>,
>> ?Paul Barry <pauljbar... at gmail.com> wrote:
>>
>> > host = '127.0.0.1' ? ? ? ? ? # Bind to all interfaces
>>
>> This threw me off the track for a little while. ?The comment is wrong!
>> You're not binding to all interfaces, you're binding specifically to
>> the loopback interface. ?For what you're doing, it's fine, but the
>> comment is still wrong.
> 
> You are right.  The example in the book actually has
> 
> host = ''
> 
> So the comment is correct.  In trying to debug what was going on, I put
> 127.0.0.1 to see if that had something to do with it, which it didn't.

Now I have to quote Aahz's email sig:

"At Resolver we've found it useful to short-circuit any doubt and just 
refer to comments in code as 'lies'. "
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


> But why not use
> 
>     print buf[0]
> 
> instead of
> 
>     sys.stdin.write(buf[0])
> 
> that much, I don't know.

print adds a trailing newline to the output, so the two lines aren't 
quite equivalent.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 18:58:34 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 22:58:34 GMT
Subject: Help understanding the decisions *behind* python? - immutable
	objects
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
Message-ID: <027cd083$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 11:24:48 -0700, John Nagle wrote:

>      An interesting issue is Python objects, which are always mutable.
> A "dict" of Python objects is allowed, but doesn't consider the contents
> of the objects, just their identity (address). Only built-in types are
> immutable; one cannot create a class of immutable objects.

Yes you can, for some definition of "can":

http://northernplanets.blogspot.com/2007/01/immutable-instances-in-python.html


Admittedly pure Python objects are only "cooperatively immutable". The 
immutability relies on the caller not going out of its way to break the 
instance, so you can mutate it if you work at it. One could, I suppose, 
try putting in complicated tricks to prevent that, but anything written 
in Python can ultimately be modified in Python.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 19:20:58 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 23:20:58 GMT
Subject: How to comment constant values?
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
	<5c1b5c1e-7677-4786-a026-b4825568cf5b@j32g2000yqh.googlegroups.com>
Message-ID: <027cd5c2$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 15:42:22 -0700, Bearophile wrote:

> Chris Rebert:
>> Only modules, classes, and functions/methods can have docstrings
>> associated with them.
>> For anything else, you have to use comments; or you can mention them in
>> the docstrings of related things.
> 
> What about adding docstrings to other Python things, especially to
> variables?

Python doesn't have variables, it has objects bound to names. Because 
__doc__ is looked up on the class, not the instance, there's not much 
point in adding a docstring to the instance (even for instances which 
allow attributes to be added). And because names are internally stored as 
strings, you can't add a docstring to the name. So what you ask for is 
impossible.

But of course that could be changed, if there was consensus that what you 
ask for would be useful. But consider the consequences:

# A thought-experiment
>>> margin = 3  # allow a little bit of whitespace
>>> margin.__doc__ = "Extra space in pixels."
>>> help(x)
=> displays "Extra space in pixels."

So far so good. But now consider two equally unacceptable situations:

(1) If the docstring sticks to the object, then you get the docstring 
inappropriately showing up in places where it should:

>>> number_of_widgets = len( [a, b, c] )
>>> help(number_of_widgets)
=> displays "Extra space in pixels."


(2) If the docstring sticks to the name, then you get the docstring 
hanging around when you recycle the name to mean something else:

>>> margin = 15/100.0  # our profit margin is 15%
>>> help(margin)
=> displays "Extra space in pixels."

Now, in a large program, one shouldn't recycle names like that, but in a 
large program, you're unlikely to programmatically look up docstrings. 
Docstrings, and the help() function, are particularly useful in an 
interactive session, which is precisely the time that you're likely to 
recycle names.


In other words, it's currently impossible to bind docstrings to 
"variables" in Python, but even more fundamentally, the request is 
semantically incompatible with the Python name/object binding model.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 19:23:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 23:23:30 GMT
Subject: How to comment constant values?
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
	<7d44ndF29p3p7U2@mid.uni-berlin.de>
Message-ID: <027cd65b$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 00:47:08 +0200, Diez B. Roggisch wrote:

>> Only modules, classes, and functions/methods can have docstrings
>> associated with them.
>> For anything else, you have to use comments; or you can mention them in
>> the docstrings of related things.
> 
> While this is technically true, writing docstrings to constants (module
> or classlevel) works when one uses tools such as epydoc to generate
> documentation.

I've never used epydoc, so I'm not sure what you mean. Presumably it uses 
source code analysis to detect:

CONSTANT = 42
"""This is a constant."""

even though the string is ignored by the compiler.

Is that correct?



-- 
Steven


From andrew-newspost at areilly.bpc-users.org  Sun Jul 26 19:28:53 2009
From: andrew-newspost at areilly.bpc-users.org (Andrew Reilly)
Date: 26 Jul 2009 23:28:53 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<h4hkvn$ef6$1@panix3.panix.com>
	<h4hm7q$6g2$1@news.eternal-september.org>
Message-ID: <7d475kF29aga9U1@mid.individual.net>

On Sun, 26 Jul 2009 09:31:06 -0400, Raffael Cavallaro wrote:

> On 2009-07-26 09:16:39 -0400, aahz at pythoncraft.com (Aahz) said:
> 
>> There are plenty of expert C++
>> programmers who switched to Python;
> 
> "plenty" is an absolute term, not a relative term. I sincerely doubt
> that the majority of python users were formerly *expert* C++
> programmers.
> 
>> your thesis only applies to the
>> legions of people who found it difficult to learn C++ in the first
>> place.
> 
> No, my thesis applies to the overwhelming majority of programmers who
> found it more difficult to *master* (i.e., not merely use) C++ as
> opposed to mastering python. BTW, this is a *complement* not a dis;
> python is a better language than C++ precisely because it is more
> sensibly and elegantly designed than C++ and therefore easier to master.

Isn't it widely accepted that the number of people who have mastered C++ 
is about five?  All of the rest of us just struggle...

[I know enough of C++ to avoid it whenever I can, and to not use it for 
my own projects.  I'm happy with a mix of C, python and lisp(or scheme).]

-- 
Andrew


From pinkeen at gmail.com  Sun Jul 26 19:44:54 2009
From: pinkeen at gmail.com (Filip)
Date: Sun, 26 Jul 2009 16:44:54 -0700 (PDT)
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
	<88e8ea19-7106-406a-a531-88c2b6893987@y7g2000yqa.googlegroups.com>
Message-ID: <0643e7ab-3136-4352-a849-a19882c3f9b2@c2g2000yqi.googlegroups.com>

On Jul 23, 3:53?am, Paul McGuire <pt... at austin.rr.com> wrote:
> # You should use raw string literals throughout, as in:
> # blah_re = re.compile(r'sljdflsflds')
> # (note the leading r before the string literal). ?raw string
> literals
> # really help keep your re expressions clean, so that you don't ever
> # have to double up any '\' characters.

Thanks, I didn't know about that, updated my code.

> # Attributes might be enclosed in single quotes, or not enclosed in
> any quotes at all.
> attr_re = re.compile('([\da-z]+?)\s*=\s*\"(.*?)\"', re.DOTALL |
> re.UNICODE | re.IGNORECASE)

Of course, you mean attribute's *value* can be enclosed in single/
double quotes?
To be true, I haven't seen single quote variant in HTML lately but I
checked it and it seems to be in the specs and it can be even quite
useful (man learns something every day).
Thank you for pointing that one out, I updated the code accordingly
(just realized that condition check REs need an update too :/).

As far as the lack of value quoting is concerned, I am not so sure I
need this - It would significanly obfuscate my REs and this practice
is rather deprecated, considered unsafe
and I've seen it only in very old websites.

> How would you extract data from a table? ?For instance, how would you
> extract the data entries from the table at this URL:http://tf.nist.gov/tf-cgi/servers.cgi? ?This would be a good example
> snippet for your module documentation.

This really seems like a nice example. I'll surely explain it in my
docs (examples are surely needed there ;)).

> Try extracting all of the <a href=...>sldjlsfjd</a> links from
> yahoo.com, and see how much of what you expect actually gets matched.

The library was used in my humble production environment, processing a
few hundred thousand+ of pages and spitting out about 10000 SQL
records so it does work quite good with a simple task like extracting
all links. However, I can't really say that the task introduced enough
diversity (there were only 9 different page templates) to say that the
library is 'tested'...

On Jul 26, 5:51 pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 23, 11:53 am, Paul McGuire <pt... at austin.rr.com> wrote:
>
> > On Jul 22, 5:43 pm, Filip <pink... at gmail.com> wrote:
>
> > # Needs re.IGNORECASE, and can have tag attributes, such as <BR
> > CLEAR="ALL">
> > line_break_re = re.compile('<br\/?>', re.UNICODE)
>
> Just in case somebody actually uses valid XHTML :-) it might be a good
> idea to allow for <br />
>
> > # what about HTML entities defined using hex syntax, such as &#xxxx;
> > amp_re = re.compile('\&(?![a-z]+?\;)', re.UNICODE | re.IGNORECASE)
>
> What about the decimal syntax ones? E.g. not only &nbsp; and &#xa0;
> but also &#160;
>
> Also, entity names can contain digits e.g. &sup1; &frac34;

Thanks for pointing this out, I fixed that. Although it has very
little impact on how the library performs its main task (I'd like to
see some comments on that ;)).


From aahz at pythoncraft.com  Sun Jul 26 19:56:59 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 16:56:59 -0700
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<mailman.3715.1248552511.8015.python-list@python.org>
	<2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>
Message-ID: <h4iqgb$ss5$1@panix3.panix.com>

In article <2a408da6-af57-45d0-a75f-4cbe384bb7f9 at s15g2000yqs.googlegroups.com>,
Michal Kwiatkowski  <constant.beta at gmail.com> wrote:
>On Jul 25, 10:00=A0pm, Jason Tackaberry <t... at urandom.ca> wrote:
>> On Sat, 2009-07-25 at 11:30 -0700, Michal Kwiatkowski wrote:
>>>
>>> Is there a way to tell if a generator has been exhausted using pure
>>> Python code? I've looked at CPython sources and it seems that
>>
>> Upon a cursory look, after a generator 'gen' is exhausted (meaning
>> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
>> None.
>
>Only in Python 2.5 or higher though. I need to support Python 2.3 and
>2.4 as well, sorry for not making that clear in the original post.

Are you sure?  It appears to work in Python 2.4; I don't have time to
check 2.3.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From tjreedy at udel.edu  Sun Jul 26 20:10:00 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 26 Jul 2009 20:10:00 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
Message-ID: <h4ir8n$eq$1@ger.gmane.org>

Michal Kwiatkowski wrote:

> The thing is I don't need the next item. I need to know if the
> generator has stopped without invoking it.

Write a one-ahead iterator class, which I have posted before, that sets 
.exhausted to True when next fails.

tjr



From nyamatongwe+thunder at gmail.com  Sun Jul 26 20:25:46 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Mon, 27 Jul 2009 00:25:46 GMT
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <mailman.3735.1248609191.8015.python-list@python.org>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>	<NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>
	<mailman.3735.1248609191.8015.python-list@python.org>
Message-ID: <eu6bm.7529$ze1.5514@news-server.bigpond.net.au>

Mark Lawrence:

> If my sleuthing is correct the problem is with these lines
> 
> ilow *= self->itemSize;
> ihigh *= self->itemSize;
> 
> in GapBuffer_slice being computed before ilow and ihigh are compared to
> anything.

   This particular bug was because ihigh is the maximum 32 bit integer
2147483647 so multiplying it by the integer item size (4) caused
overflow. Adding an extra check fixes this:
    if (ihigh > self->lengthBody / self->itemSize)
        ihigh = self->lengthBody / self->itemSize;

   Committed a new version 1.02 and new downloads are available from
Google code.
http://code.google.com/p/gapbuffer/downloads/list

   Neil


From jackdied at gmail.com  Sun Jul 26 20:36:17 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Sun, 26 Jul 2009 20:36:17 -0400
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <b8e622740907261736s3b340e42m83d65f1e292f7ebc@mail.gmail.com>

On Mon, Jul 20, 2009 at 5:57 AM, casebash<walkraft at gmail.com> wrote:
> Hi,
>
> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

It depends on how mutable you want your strings.  There have been
several patches proposed on python-dev over the years that do things
like lazy concatenation and ropes.  They were always shot down because
the implementation or the semantics were very complicated.

-Jack


From tdelaney at avaya.com  Sun Jul 26 20:53:33 2009
From: tdelaney at avaya.com (Delaney, Timothy (Tim))
Date: Mon, 27 Jul 2009 08:53:33 +0800
Subject: missing 'xor' Boolean operator
In-Reply-To: <8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>
Message-ID: <E4C7BCAB1872014F81CEAACD25699B8C014E60E1@301081ANEX2.global.avaya.com>

Mark Dickinson wrote:

>> Since the 'and' and 'or' already return objects (and objects
>> evaluate to true or false), then 'xor' should behave likewise, IMO.
>> I expect that would be the case if it were ever added to the
>> language. 
> 
> I'm not so sure.  Did you ever wonder why the any() and all()
> functions introduced in 2.5 return a boolean rather than returning
> one of their arguments?  (I did, and I'm still not sure what the
> answer is.)

Consider the case of any() and all() operating on an empty iterable.
What type should they return?

It is impossible in the case of any() and all() to always return one of
the elements due to this edge case. Similarly, it is impossible in all
cases for a boolean xor to return one of the arguments - if both
arguments evaluate to a true (Something) value, xor must return a false
(Nothing) result.

Tim Delaney


From bearophileHUGS at lycos.com  Sun Jul 26 21:09:47 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Sun, 26 Jul 2009 18:09:47 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
Message-ID: <b0afe5f7-0cd9-43af-ba1e-0e405d5ceb5f@h21g2000yqa.googlegroups.com>

William Dode':
> I updated the script (python, c and java) with your unrolled version
> + somes litle thinks.
[...]
> c 1.85s
> gcj 2.15s
> java 2.8s
> python2.5 + psyco 3.1s
> unladen-2009Q2 145s (2m45)
> python2.5 254s (4m14s)
> python3.1 300s (5m)
> ironpython1.1.1 680s (11m20)

Sorry for being late, I was away.

In your last C version this code is useless because the C compiler is
able to perform such simple optimization by itself (but probably
Python isn't able, so if you want the code to be the similar in all
versions it may be better to keep it):

shift_0=shift[0];
shift_1=shift[1];
shift_2=shift[2];
shift_3=shift[3];
shift_4=shift[4];
shift_5=shift[5];
shift_6=shift[6];
shift_7=shift[7];


This part in the Python code is useless:

shift_0 = shift[0]
shift_1 = shift[1]
shift_2 = shift[2]
shift_3 = shift[3]
shift_4 = shift[4]
shift_5 = shift[5]
shift_6 = shift[6]
shift_7 = shift[7]

Because later you copy values locally anyway:

def solve(nb, x, y,
        SIDE=SIDE, SQR_SIDE=SQR_SIDE, circuit=circuit,
        shift_0=shift_0,
        shift_1=shift_1,
        shift_2=shift_2,
        shift_3=shift_3,
        shift_4=shift_4,
        shift_5=shift_5,
        shift_6=shift_6,
        shift_7=shift_7,
        ):

So doing something like this is probably enough:

def solve(nb, x, y,
        SIDE=SIDE, SQR_SIDE=SQR_SIDE, circuit=circuit,
        shift_0=shift[0],
        shift_1=shift[1],
        shift_2=shift[2],
        shift_3=shift[3],
        shift_4=shift[4],
        shift_5=shift[5],
        shift_6=shift[6],
        shift_7=shift[7],
        ):

In low-level languages like C unrolling has to be done with care, to
avoid slowing down the code.

I have tried your latest C version using your compiler options, my
MinGW based on GCC 4.3.2 produces a crash at runtime. Using LLVM-GCC
it runs in 1.31 seconds. The D version is a bit less optimized than
your last C versions, yet using DMD it runs in 1.08-1.10 seconds.
Let's see if someone is able to write a C version faster than that D
code :-)

Have you have compiled/read my D version? In the D version you may
have missed that I did use an extra trick: unsigned integers, so it
needs just two tests to see if a number is in the 0-5, 0-5 square :-)
Note that Pyd, the Python-D bridge, may work with the latest DMD
version still (and it works if you use a bit older DMD compiler):
http://pyd.dsource.org/

Bye,
bearophile


From greg at cosc.canterbury.ac.nz  Sun Jul 26 21:12:26 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Mon, 27 Jul 2009 13:12:26 +1200
Subject: missing 'xor' Boolean operator
In-Reply-To: <mailman.3711.1248543076.8015.python-list@python.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<knclug.j10@spenarnc.xs4all.nl>
	<mailman.3711.1248543076.8015.python-list@python.org>
Message-ID: <7d4d6gF28qk7kU1@mid.individual.net>

Terry Reedy wrote:

> In Math and Python, a<b<c means a<b and b<c, not (a<b)<c or a<(b<c).
> != is a comparison operator like <,

Although Python extends the chaining principle to
!=, this is somewhat questionable, because
a < b and b < c implies a < c, but a != b and
b != c does not imply a != c.

I'm not sure I've ever seen a mathematician
write a != b != c, but if I did, I would tend
to think he meant to say that none of a, b,
c are equal to any other. That's not what it
means in Python, though.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Sun Jul 26 21:30:41 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Mon, 27 Jul 2009 13:30:41 +1200
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
Message-ID: <7d4e8nF2a9i83U1@mid.individual.net>

Michal Kwiatkowski wrote:

> The first generator isn't finished, it yielded 1 and None. Second one
> is exhausted after yielding a single value (1). The problem is that,
> under Python 2.4 or 2.3 both invocations will generate the same trace
> output.

This seems to be a deficiency in the trace mechanism.
There really ought to be a 'yield' event to distinguish
yields from returns.

You could put in a feature request on python-dev
concerning this.

-- 
Greg


From aahz at pythoncraft.com  Sun Jul 26 22:44:24 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 19:44:24 -0700
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3648.1248429993.8015.python-list@python.org>
	<h4htk2$fmb$1@panix3.panix.com>
	<mailman.3747.1248642434.8015.python-list@python.org>
Message-ID: <h4j4a8$ghf$1@panix3.panix.com>

In article <mailman.3747.1248642434.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>
>Ok, if you insist...
>
>NLMPI = Ni La M?s Puta Idea.
>IHNFI = I Have No Fucking Idea.

Thanks!
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From nidlobm at hotmail.com  Sun Jul 26 23:14:52 2009
From: nidlobm at hotmail.com (Michael Boldin)
Date: Sun, 26 Jul 2009 23:14:52 -0400
Subject: SEC doc parsing
Message-ID: <BLU134-W25E50A7805FABCBFD1985CA0140@phx.gbl>


I am looking for any parsing routines (written in python), for Security Exchange Commision (SEC) documents. These documents are on the SEC's EDGAR system  (at  ftp://ftp.sec.gov ) and I am especially interested in insider trading files known as Forms 3,4 and 5.

 

_________________________________________________________________
NEW mobile Hotmail. Optimized for YOUR phone.  Click here.
http://windowslive.com/Mobile?ocid=TXT_TAGLM_WL_CS_MB_new_hotmail_072009
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090726/56bb1768/attachment.html>

From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 23:18:53 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 27 Jul 2009 03:18:53 GMT
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
	<mailman.3752.1248653417.8015.python-list@python.org>
Message-ID: <027d0d84$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:

> Michal Kwiatkowski wrote:
> 
>> The thing is I don't need the next item. I need to know if the
>> generator has stopped without invoking it.
> 
> Write a one-ahead iterator class, which I have posted before, that sets
> .exhausted to True when next fails.


And hope that the generator doesn't have side-effects...


-- 
Steven


From robert.kern at gmail.com  Mon Jul 27 00:11:12 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sun, 26 Jul 2009 23:11:12 -0500
Subject: PyQt GUI
In-Reply-To: <4ee78bf1-476d-4e41-b9da-c20297aad861@13g2000prl.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
	<mailman.2864.1247095779.8015.python-list@python.org>	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>	<mailman.2902.1247154895.8015.python-list@python.org>	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>	<16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>
	<mailman.3611.1248368602.8015.python-list@python.org>
	<4ee78bf1-476d-4e41-b9da-c20297aad861@13g2000prl.googlegroups.com>
Message-ID: <h4j9d1$p96$1@ger.gmane.org>

On 2009-07-26 07:04, Helvin wrote:

> C:\Qt\VTKbin7\Wrapping\Python>python setup.py install
> Traceback (most recent call last):
>    File "setup.py", line 138, in<module>
>      raise "ERROR: Must specify BUILD_TYPE=<config-name>  on command
> line."
> TypeError: exceptions must be classes or instances, not str
>
> Is it just a small error with input format or something?

Read the source, please:

# The build type ('Release', 'Debug' etc.).  If vtk_has_configuration_types
# is true this must be set.  It may be set on the command line by something
# like 'BUILD_TYPE=Release'.  For example::
#   python setup.py install --prefix=D:\\Python23 BUILD_TYPE=Release

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From robert.kern at gmail.com  Mon Jul 27 00:16:24 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sun, 26 Jul 2009 23:16:24 -0500
Subject: How to comment constant values?
In-Reply-To: <027cd65b$0$5185$c3e8da3@news.astraweb.com>
References: <200907270749.58845.devent@deventm.org>	<mailman.3750.1248645992.8015.python-list@python.org>	<7d44ndF29p3p7U2@mid.uni-berlin.de>
	<027cd65b$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4j9mo$p96$2@ger.gmane.org>

On 2009-07-26 18:23, Steven D'Aprano wrote:
> On Mon, 27 Jul 2009 00:47:08 +0200, Diez B. Roggisch wrote:
>
>>> Only modules, classes, and functions/methods can have docstrings
>>> associated with them.
>>> For anything else, you have to use comments; or you can mention them in
>>> the docstrings of related things.
>> While this is technically true, writing docstrings to constants (module
>> or classlevel) works when one uses tools such as epydoc to generate
>> documentation.
>
> I've never used epydoc, so I'm not sure what you mean. Presumably it uses
> source code analysis to detect:
>
> CONSTANT = 42
> """This is a constant."""
>
> even though the string is ignored by the compiler.
>
> Is that correct?

epydoc 3 can actually parse the file to grab comments with a "#:" marker:

#: This is a constant.
CONSTANT = 42

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dpresley at midiowa.net  Mon Jul 27 00:20:51 2009
From: dpresley at midiowa.net (drednot57)
Date: Sun, 26 Jul 2009 21:20:51 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <6ac8501e-b3ca-403b-8edb-c055b65bbff1@e11g2000yqo.googlegroups.com>

To the best of my recollection, the len() function only applies to
container objects; i. e. tuples, lists, strings, etc.  an integer
object is not a container, thus one receives an error when sending an
int as an argument for len().


From tjreedy at udel.edu  Mon Jul 27 02:02:19 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 27 Jul 2009 02:02:19 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <027d0d84$0$5185$c3e8da3@news.astraweb.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>	<877hxw4avj.fsf@benfinney.id.au>	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>	<mailman.3752.1248653417.8015.python-list@python.org>
	<027d0d84$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4jfta$6b1$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:
> 
>> Michal Kwiatkowski wrote:
>>
>>> The thing is I don't need the next item. I need to know if the
>>> generator has stopped without invoking it.
>> Write a one-ahead iterator class, which I have posted before, that sets
>> .exhausted to True when next fails.
> 
> 
> And hope that the generator doesn't have side-effects...

If run to exhastion, the same number of side-effects happen.
The only difference is that they each happen once step happpen sooner. 
For reading a file that is irrelevant. Much else, and the iterator is 
not just an iterator.

tjr




From tjreedy at udel.edu  Mon Jul 27 02:05:55 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 27 Jul 2009 02:05:55 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <7d4d6gF28qk7kU1@mid.individual.net>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<knclug.j10@spenarnc.xs4all.nl>	<mailman.3711.1248543076.8015.python-list@python.org>
	<7d4d6gF28qk7kU1@mid.individual.net>
Message-ID: <h4jg42$6b1$2@ger.gmane.org>

greg wrote:
> Terry Reedy wrote:
> 
>> In Math and Python, a<b<c means a<b and b<c, not (a<b)<c or a<(b<c).
>> != is a comparison operator like <,
> 
> Although Python extends the chaining principle to
> !=, this is somewhat questionable, because
> a < b and b < c implies a < c, but a != b and
> b != c does not imply a != c.
> 
> I'm not sure I've ever seen a mathematician
> write a != b != c, but if I did, I would tend
> to think he meant to say that none of a, b,
> c are equal to any other. That's not what it
> means in Python, though.

However, == is transitive, and a == b == c is quite common.
It would hardly do to have different rules for !=.

Either we have a uniform rule for a compare_op b compare_ob c, as we do, 
or we have several fussy rules that would be hard to remember.



From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 27 02:22:54 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 27 Jul 2009 06:22:54 GMT
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
	<mailman.3752.1248653417.8015.python-list@python.org>
	<027d0d84$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3757.1248674553.8015.python-list@python.org>
Message-ID: <027d38a5$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 02:02:19 -0400, Terry Reedy wrote:

> Steven D'Aprano wrote:
>> On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:
>> 
>>> Michal Kwiatkowski wrote:
>>>
>>>> The thing is I don't need the next item. I need to know if the
>>>> generator has stopped without invoking it.
>>> Write a one-ahead iterator class, which I have posted before, that
>>> sets .exhausted to True when next fails.
>> 
>> 
>> And hope that the generator doesn't have side-effects...
> 
> If run to exhastion, the same number of side-effects happen. The only
> difference is that they each happen once step happpen sooner. For
> reading a file that is irrelevant. Much else, and the iterator is not
> just an iterator.

I believe the OP specifically said he needs to detect whether or not an 
iterator is exhausted, without running it to exhaustion, so you shouldn't 
assume that the generator has been exhausted.

When it comes to side-effects, timing matters. For example, a generator 
which cleans up after it has run (deleting temporary files, closing 
sockets, etc.) will leave the environment in a different state if run to 
exhaustion than just before exhaustion. Even if you store the final 
result in a one-ahead class, you haven't saved the environment, and that 
may be significant.

(Of course, it's possible that it isn't significant. Not all differences 
make a difference.)

The best advice is, try to avoid side-effects, especially in generators.


-- 
Steven


From jayshree06comp at gmail.com  Mon Jul 27 02:47:00 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Sun, 26 Jul 2009 23:47:00 -0700 (PDT)
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
	<b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>
	<m2ocrbk1k2.fsf@cs.uu.nl>
Message-ID: <e004759b-4fd5-49b4-b3a6-1e2063a9aed9@v36g2000yqv.googlegroups.com>

On Jul 23, 5:48?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> jayshree <jayshree06c... at gmail.com> (j) wrote:
> >j> On Jul 21, 8:59?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>> The recipient_public_key.pem file is the public key of the recipient
> >>> which means the person that is going to receive the encrypted message.
> >>> You should get it from the recipient him/herself or from some key store
> >>> where s/he has deposited it.
>
> [...]
>
> >j> error coming like - IOError: [Errno 2] No such file or directory:
> >j> 'recipient_public_key.pem'
> >j> Is this not the inbuilt file.
> >j> How should i create such type of file.
>
> You don't create it. See above. If you understand what is is you know
> why it can't be builtin. If you don't understand it is better if you
> first learn about OpenSSL, otherwise you run the risk to make serious
> errors.
>
> If you are just experimenting to create a message for yourself then you
> have to create the public key because you are then the recipient
> yourself. That has been answered onhttp://stackoverflow.com/questions/1169798/m2crypto-package
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

import M2Crypto
from M2Crypto import RSA,SSL
def encrypt():
    pk = open('my_key.public.pem', 'rb').read()
    rsa = M2Crypto.RSA.load_pub_key(pk) #return a M2Crypto.RSA.RSA_pub
object.
    plaintext = 4545479545655576767767686688782344
    msg = rsa.public_encrypt(plaintext,RSA.pkcs1_padding)
    print msg;
    encrypt()

This is code i am refering.
The Problem is coming with .pem file.
I also asked this questions at  http://stackoverflow.com/questions/1176864/problem-with-the-pem-file-closed
which has not been answered .
please help me out....

thanks


From nagle at animats.com  Mon Jul 27 03:06:36 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 00:06:36 -0700
Subject: Help understanding the decisions *behind* python? - immutable
	objects
In-Reply-To: <027cd083$0$5185$c3e8da3@news.astraweb.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>	<mailman.3511.1248244497.8015.python-list@python.org>	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
	<027cd083$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4a6d514d$0$1641$742ec2ed@news.sonic.net>

Steven D'Aprano wrote:
> On Sun, 26 Jul 2009 11:24:48 -0700, John Nagle wrote:
> 
>>      An interesting issue is Python objects, which are always mutable.
>> A "dict" of Python objects is allowed, but doesn't consider the contents
>> of the objects, just their identity (address). Only built-in types are
>> immutable; one cannot create a class of immutable objects.
> 
> Yes you can, for some definition of "can":
> 
> http://northernplanets.blogspot.com/2007/01/immutable-instances-in-python.html
> 
> 
> Admittedly pure Python objects are only "cooperatively immutable". 

    Right.  I've been thinking about this as a way of improving
concurrency handling.  The general idea is that objects shared
across threads would have to be either be immutable or synchronized.
Regular objects would be limited to a single thread.  It's a path
to multithread programs without a global lock.  Needs more work
to become a serious proposal.  (It may not be worth the trouble;
a few years ago we were hearing about how 64-core CPUs were going
to become mainstream, but instead, the industry is going in the
direction of the same compute power for less money and with
less power consumption.)

				John Nagle


From abhigyan_agrawal at in.ibm.com  Mon Jul 27 03:11:42 2009
From: abhigyan_agrawal at in.ibm.com (abhi)
Date: Mon, 27 Jul 2009 00:11:42 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
Message-ID: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>

Hi,
    I am facing a problem using PyArg_ParseTuple() in my C-API
extension. Here is a small repro of the function:

static PyObject *parsetuple_test(PyObject *self, PyObject *args)
{
	SQLUSMALLINT param_no = 0;
	PyObject *py_obj = NULL;

	if (!PyArg_ParseTuple(args, "Oi", &py_obj, &param_no)){

		return NULL;
	}
	printf("%d\n", param_no);
	return NULL;
}

This function works fine and prints the correct value passed
(param_no) when I test it on Linux or Windows. However, it always
prints 0 (initial value defined in function) when I run it on AIX.

I think the problem is with "Oi" argument, if I replace that with "OO"
and specifically convert it integer/sqlsmallint. It works fine on AIX,
but I want to use "i" and not "O".

Any ideas on what is the reason behind the problem and how to fix
this?

Thanks,
Abhigyan


From jayshree06comp at gmail.com  Mon Jul 27 03:28:50 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Mon, 27 Jul 2009 00:28:50 -0700 (PDT)
Subject: open a file in python
Message-ID: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>

pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()

Please tell me how to open a file placed in any directory or in same
directory.

After opening this file i want to use the contain (public key ) for
encryption





thanks


From metallourlante at gmail.com  Mon Jul 27 03:40:09 2009
From: metallourlante at gmail.com (Alex)
Date: Mon, 27 Jul 2009 00:40:09 -0700 (PDT)
Subject: web page retrieve problems
References: <16343e3d-1be4-422b-8bff-c07fa4aa4c54@j9g2000prh.googlegroups.com>
Message-ID: <7dd16ce7-8442-4e67-a949-442b287e00dd@j21g2000yqe.googlegroups.com>

On Jul 26, 8:57?am, golu <bhardwajjaye... at gmail.com> wrote:
> the following function retrieves pages from the web and saves them in
> a specified dir. i want to extract the respective filenames from the
> urls e.g the page code.google.com shud be saved as code-google.htm ?or
> something similar. can u suggest me a way to do it

Try with urllib.urlretrieve from standard lib:

urllib.urlretrieve(url[, filename[, reporthook[, data]]])?
Copy a network object denoted by a URL to a local file, if necessary.
If the URL points to a local file, or a valid cached copy of the
object exists, the object is not copied. Return a tuple (filename,
headers) where filename is the local file name under which the object
can be found, and headers is whatever the info() method of the object
returned by urlopen() returned (for a remote object, possibly cached).
Exceptions are the same as for urlopen().


From kushal.kumaran+python at gmail.com  Mon Jul 27 04:09:26 2009
From: kushal.kumaran+python at gmail.com (Kushal Kumaran)
Date: Mon, 27 Jul 2009 13:39:26 +0530
Subject: open a file in python
In-Reply-To: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
Message-ID: <1e364c4e0907270109u2aa8e702oa3ebaaab065f5e90@mail.gmail.com>

On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06comp at gmail.com> wrote:
> pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>
> Please tell me how to open a file placed in any directory or in same
> directory.
>
> After opening this file i want to use the contain (public key ) for
> encryption
>

Does the code you've put into your message not read that file?  If you
get an exception, copy-paste in the traceback message you get into
your mail.

-- 
kushal


From piet at cs.uu.nl  Mon Jul 27 04:18:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 10:18:20 +0200
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org>
Message-ID: <m21vo2czeb.fsf@cs.uu.nl>

>>>>> Dotan Cohen <dotancohen at gmail.com> (DC) wrote:

>DC> Referring to this article:
>DC> http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/

>DC> The author, who is specifically looking for math-related functions, writes:
>DC> """
>DC> The dream algorithm R&D tool would be similar to Matlab or Mathematica
>DC> but could be compiled to fast, efficient binaries similar to ANSI C
>DC> and would be available for all platforms. An integrated GUI builder
>DC> similar to Visual Basic and integrated network support would be
>DC> helpful.
>DC> """

>DC> It looks to me like he is looking for Python.

No fast, efficient binaries yet, and no integrated GUI builder.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From vesa.koppa at gmail.com  Mon Jul 27 04:51:51 2009
From: vesa.koppa at gmail.com (=?ISO-8859-1?Q?Vesa_K=F6pp=E4?=)
Date: Mon, 27 Jul 2009 11:51:51 +0300
Subject: How do I generate dia diagrams from python source code?
In-Reply-To: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
References: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
Message-ID: <4a6d6aa6$0$24756$4f793bc4@news.tdc.fi>

Qauzzix wrote:
> Greetings.
> 
> Since I have been using dia to make my UML diagrams. I also found an
> util named dia2code that generates python code from dia diagram. Now
> that I have that option I really want to find a way to generate dia
> diagram from existing code and/or maintain my diagrams.
> 
> I have been googling  like crazy trying to find a way but with no
> luck. Anyone here know how to do this?
> 
> Peace,
>  - Jakob Sv. Bjarnason

Hi.

There is this utility called autodia.
http://www.aarontrevena.co.uk/opensource/autodia/
I think it does what you want. It is written in perl.
It can read several languages and outputs dia diagrams.

BTW, I found it by going to dia2code homepage and then to
its links page. It is listed in there.

-- 
Vesa


From s.selvamsiva at gmail.com  Mon Jul 27 04:53:33 2009
From: s.selvamsiva at gmail.com (S.Selvam)
Date: Mon, 27 Jul 2009 14:23:33 +0530
Subject: Itext for Python
In-Reply-To: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com>
References: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com>
Message-ID: <b423b9550907270153v5b21cb35wc3741c8d5775e574@mail.gmail.com>

On Sun, Jul 26, 2009 at 11:52 PM, Santhosh Kumar
<santhosh.vkumar at gmail.com>wrote:

> Hi all,           One of my cousin  suggested me to do a IText
> PDF converter for python. Actually I heard that there is
> no separate IText converter either we have to go for jython or GCJ with
> wrapper. Instead of wrapping, my plan is to create a separate module with
> Python and I am thinking of doing this in as my final year project also.
> Kindly give me your suggestion.
>


As for as i know, no pure python module exists for iText PDF generator,
where iText seems to be a standard one for PDF related works.There are some
other modules for pdf work but might not be as standard as iText.Surely some
senior programmers  will suggest you better way to proceed further.


>         With anticipation,
>
> SanthoshVKumar.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>


-- 
Yours,
S.Selvam
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090727/bcaf8383/attachment.html>

From Tom.sully at gmx.com  Mon Jul 27 04:58:48 2009
From: Tom.sully at gmx.com (Tom)
Date: Mon, 27 Jul 2009 01:58:48 -0700 (PDT)
Subject: Globalize all variables in function without knowing names.
References: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>
	<mailman.3748.1248642820.8015.python-list@python.org>
	<5649dfb8-01a6-490d-bf30-b4a5206e644e@j21g2000yqe.googlegroups.com>
	<027cce66$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <50a401f0-b203-4dcd-baa9-22895a068f3b@r27g2000vbn.googlegroups.com>

> Dictionaries are fundamental to Python and very useful. Not learning
> about them before starting to write code is like not learning about the
> accelerator pedal before starting to drive a car.

Heh, I just looked at the actual tutorial for Dictionaries and I have
to say they are very useful. Basically just arrays with strings(or any
other data type, except lists) instead of numbers. I'll work on trying
to integrate them into my language code as, like you said, user
data... Then when a user requests a variable it just accessess the
dictionary, that should work. Thanks!
This is easier than I thought.

> Have you done the tutorial?

I did the first few sections, and then flipped back to it later on to
find out what I needed to know as I coded applications. A bad idea, in
retrospect, particilary as it slowed down my coding time alot.


From hendrik at microcorp.co.za  Mon Jul 27 05:05:06 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Mon, 27 Jul 2009 11:05:06 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
Message-ID: <200907271105.06692.hendrik@microcorp.co.za>

On Sunday 26 July 2009 21:26:46 David Robinow wrote:

>
>  I'm a mediocre programmer. Does this mean I should switch to PHP?

I have searched, but I can find nothing about this mediocre language.

Could you tell us more?

- Hendrik


From dickinsm at gmail.com  Mon Jul 27 05:12:16 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Mon, 27 Jul 2009 02:12:16 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3754.1248656735.8015.python-list@python.org>
Message-ID: <668280c4-6c52-4c2e-ab6f-9b3701399134@s15g2000yqs.googlegroups.com>

On Jul 27, 1:53?am, "Delaney, Timothy (Tim)" <tdela... at avaya.com>
wrote:
> Mark Dickinson wrote:
> >> Since the 'and' and 'or' already return objects (and objects
> >> evaluate to true or false), then 'xor' should behave likewise, IMO.
> >> I expect that would be the case if it were ever added to the
> >> language.
>
> > I'm not so sure. ?Did you ever wonder why the any() and all()
> > functions introduced in 2.5 return a boolean rather than returning
> > one of their arguments? ?(I did, and I'm still not sure what the
> > answer is.)
>
> Consider the case of any() and all() operating on an empty iterable.
> What type should they return?
>
> It is impossible in the case of any() and all() to always return one of
> the elements due to this edge case.

Yes, of course; the alternative implementation I was thinking of
was the one that I implemented eons ago for my own pre-2.5 code,
where I defined any and all roughly as:

any([x1, x2, x3, ...]) <-> False or x1 or x2 or x3 or ...
all([x1, x2, x3, ...]) <-> True and x1 and x2 and x3 and ...

At the time this seemed like the obvious choice, so I was a bit
surprised when it was chosen to always return a bool instead in
the official versions.

Now that I'm older and wise^H^H^H^H, well, maybe just older, the
pure bool version seems cleaner and less error-prone, even if
it's mildly inconsistent with the behaviour of and and or.

Mark


From sjmachin at lexicon.net  Mon Jul 27 05:25:19 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 27 Jul 2009 02:25:19 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
References: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>
Message-ID: <635a7311-62e1-4da5-98ad-b62cfa150287@k30g2000yqf.googlegroups.com>

On Jul 27, 5:11?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
> Hi,
> ? ? I am facing a problem using PyArg_ParseTuple() in my C-API
> extension. Here is a small repro of the function:
>
> static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> {
> ? ? ? ? SQLUSMALLINT param_no = 0;

Sorry, my crystal ball is on the fritz. What is SQLUSMALLINT on
Windows/Linux/AIX?
What does
    printf("%d %d %d\n", sizeof(SQLUSMALLINT), sizeof(int), sizeof
(long));
give you on each platform?

> ? ? ? ? PyObject *py_obj = NULL;
>
> ? ? ? ? if (!PyArg_ParseTuple(args, "Oi", &py_obj, &param_no)){
>
> ? ? ? ? ? ? ? ? return NULL;
> ? ? ? ? }
> ? ? ? ? printf("%d\n", param_no);
> ? ? ? ? return NULL;
>
> }
>
> This function works fine and prints the correct value passed
> (param_no) when I test it on Linux or Windows. However, it always
> prints 0 (initial value defined in function) when I run it on AIX.

Consider that 0 could have been plucked out of the air and has nothing
to do with the initial value of param_no. Try initialising it to
something distinctive, like 0xfedcba98. Use %08x format in the printf
rather than %d.


>
> I think the problem is with "Oi" argument, if I replace that with "OO"
> and specifically convert it integer/sqlsmallint. It works fine on AIX,
> but I want to use "i" and not "O".
>
> Any ideas on what is the reason behind the problem and how to fix
> this?

I jump-started the crystal ball from the over-head tram wire and saw
this: """SQLSMALLINT is 16 bits on all platforms, int/long is 32 bits
on all platforms, first 2 are little-endian, AIX is bigendian, the "i"
format expects SIGNED int /long, so param_no is getting (win:x,
linux:x, aix:0) and the next 16 bits in memory are getting trashed
with (win:0, linux:0, aix:x) (when x is your input smallish integer)
and luckily this trashing didn't cause a crash. You can receive the
result from the function in an int/long then have code to reject it if
it won't fit into a SQLUSMALLINT, and cast it otherwise. If you don't
care about overflow (NOT recommended), just use "H" format instead if
"i" format"""

Could be wrong, really shouldn't subject precision instruments to 415V
DC, only OPs :-)

N.B. to detect endianness : use print sys.byteorder

HTH,
John


From jayshree06comp at gmail.com  Mon Jul 27 05:37:47 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Mon, 27 Jul 2009 02:37:47 -0700 (PDT)
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
Message-ID: <cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>

On Jul 27, 1:09?pm, Kushal Kumaran <kushal.kumaran+pyt... at gmail.com>
wrote:
> On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06c... at gmail.com> wrote:
> > pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>
> > Please tell me how to open a file placed in any directory or in same
> > directory.
>
> > After opening this file i want to use the contain (public key ) for
> > encryption
>
> Does the code you've put into your message not read that file? ?If you
> get an exception, copy-paste in the traceback message you get into
> your mail.
>
> --
> kushal


    try:
        pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
    except IOError:
        print "Error: can\'t find file or read data"
    else:
        print "reading from file successfully"

>Still no error it gives .what to do?


From m_tayseer82 at yahoo.com  Mon Jul 27 05:39:30 2009
From: m_tayseer82 at yahoo.com (Mohammad Tayseer)
Date: Mon, 27 Jul 2009 02:39:30 -0700 (PDT)
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <m21vo2czeb.fsf@cs.uu.nl>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
Message-ID: <468250.83203.qm@web31106.mail.mud.yahoo.com>

You can generate binaries using py2exe, and you can create UI using Tkinter (which is very easy) or wxPython (which have GUI builders)

 Mohammad Tayseer
http://spellcoder.com/blogs/tayseer





________________________________
From: Piet van Oostrum <piet at cs.uu.nl>
To: python-list at python.org
Sent: Monday, July 27, 2009 11:18:20 AM
Subject: Re: Looking for a dream language: sounds like Python to me.

>>>>> Dotan Cohen <dotancohen at gmail.com> (DC) wrote:

>DC> Referring to this article:
>DC> http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/

>DC> The author, who is specifically looking for math-related functions, writes:
>DC> """
>DC> The dream algorithm R&D tool would be similar to Matlab or Mathematica
>DC> but could be compiled to fast, efficient binaries similar to ANSI C
>DC> and would be available for all platforms. An integrated GUI builder
>DC> similar to Visual Basic and integrated network support would be
>DC> helpful.
>DC> """

>DC> It looks to me like he is looking for Python.

No fast, efficient binaries yet, and no integrated GUI builder.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org
-- 
http://mail.python.org/mailman/listinfo/python-list



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090727/2839d885/attachment.html>

From deets at nospam.web.de  Mon Jul 27 05:55:02 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 11:55:02 +0200
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
	<cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>
Message-ID: <7d5brmF2a1alcU1@mid.uni-berlin.de>

jayshree wrote:

> On Jul 27, 1:09?pm, Kushal Kumaran <kushal.kumaran+pyt... at gmail.com>
> wrote:
>> On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06c... at gmail.com>
>> wrote:
>> > pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>>
>> > Please tell me how to open a file placed in any directory or in same
>> > directory.
>>
>> > After opening this file i want to use the contain (public key ) for
>> > encryption
>>
>> Does the code you've put into your message not read that file? ?If you
>> get an exception, copy-paste in the traceback message you get into
>> your mail.
>>
>> --
>> kushal
> 
> 
>     try:
>         pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>     except IOError:
>         print "Error: can\'t find file or read data"
>     else:
>         print "reading from file successfully"
> 
>>Still no error it gives .what to do?

Erm - so it doesn't give an error - which means you have successfully opened
a file, and read it's contents.

So what exactly is your problem?

Diez


From nogetfx at gmail.com  Mon Jul 27 06:18:55 2009
From: nogetfx at gmail.com (Lars)
Date: Mon, 27 Jul 2009 03:18:55 -0700 (PDT)
Subject: Call function from another class
Message-ID: <4b6b0e4b-b85b-43cf-a695-e3a722de01cc@e11g2000yqo.googlegroups.com>

Hi
I'm trying to make an simple image viewer in wxPython and rotate an
image with a slider. The code at Pastebin is striped down at bit. The
class Frame(wx.Frame) is the main window, the function "def
CreateMenuBar" (l. 39) creates a menu, where the function "def onRotate
(self,event):" (l. 43) is called. The slider appear in at 2nd window,
class rotationSlider(wx.Frame).
My problem is what to do, when the Okay button is pressed in the
"rotationSlider" frame. How to get the slider value to my main window
and how to call a function to do the rotation. I tried something with
a global variable, but it would make no difference regarding the
function problem. Amongst the other things I've tried is to bind the
event of the 2nd/slider window closing (l. 46), but no.
Python code at Pastebin: http://pastebin.com/m7c24ec34

So some help on Classes and etc., would be appreciated.

/Lars


From himanshu.garg at gmail.com  Mon Jul 27 06:38:04 2009
From: himanshu.garg at gmail.com (++imanshu)
Date: Mon, 27 Jul 2009 03:38:04 -0700 (PDT)
Subject: _msi.Record object has no attribute 'GetString'
Message-ID: <32e0b242-8635-40b5-a366-2c9967e64e1c@d4g2000yqa.googlegroups.com>

The documentation (http://docs.python.org/library/msilib.html#record-
objects) for msilib mentions the GetString() method on Record objects.
However, the following snippet :-

db = msilib.OpenDatabase(os.path.join(root, file),
msilib.MSIDBOPEN_READONLY)
view = db.OpenView('SELECT * FROM Property')
view.Execute(None)
r = view.Fetch()
print dir(r)
print r.GetString(0)

gives me this error :-

c:\>python msi.py
['ClearData', 'GetFieldCount', 'SetInteger', 'SetStream', 'SetString',
__class__', '__delattr__', '__doc__', '__getattribute__', '__hash__',
'__init__', '__new__', __reduce__', '__reduce_ex__', '__repr__',
'__setattr__', '__str__']
Traceback (most recent call last):
  File "msi.py", line 18, in <module>
    print r.GetString(0)
AttributeError: '_msi.Record' object has no attribute 'GetString'

Am I missing something?

Thank You,
Himanshu


From deets at nospam.web.de  Mon Jul 27 06:43:14 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 12:43:14 +0200
Subject: Call function from another class
References: <4b6b0e4b-b85b-43cf-a695-e3a722de01cc@e11g2000yqo.googlegroups.com>
Message-ID: <7d5em2F2anm94U1@mid.uni-berlin.de>

Lars wrote:

> Hi
> I'm trying to make an simple image viewer in wxPython and rotate an
> image with a slider. The code at Pastebin is striped down at bit. The
> class Frame(wx.Frame) is the main window, the function "def
> CreateMenuBar" (l. 39) creates a menu, where the function "def onRotate
> (self,event):" (l. 43) is called. The slider appear in at 2nd window,
> class rotationSlider(wx.Frame).
> My problem is what to do, when the Okay button is pressed in the
> "rotationSlider" frame. How to get the slider value to my main window
> and how to call a function to do the rotation. I tried something with
> a global variable, but it would make no difference regarding the
> function problem. Amongst the other things I've tried is to bind the
> event of the 2nd/slider window closing (l. 46), but no.
> Python code at Pastebin: http://pastebin.com/m7c24ec34
> 
> So some help on Classes and etc., would be appreciated.

If I'm not mistaken, in "doRotate" you should be able to refer to the
to-be-closed dialog via

self.frameRotate

Now if you change the "sliderUpdate"-code to store that angle instead of
just letting it fall out of scope, you could access that value through
frameRotate:

def sliderUpdate(self, event):
        angle=self.slider.GetValue()
        ROTATION_ANGLE=angle
        self.angle = angle 
        self.Destroy()



def doRotate(self,event):
    """Rotating image"""
    print self.frameRotate.angle


Diez
 


From abhigyan_agrawal at in.ibm.com  Mon Jul 27 06:49:04 2009
From: abhigyan_agrawal at in.ibm.com (abhi)
Date: Mon, 27 Jul 2009 03:49:04 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
References: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>
	<635a7311-62e1-4da5-98ad-b62cfa150287@k30g2000yqf.googlegroups.com>
Message-ID: <43b1acda-b518-40ef-acde-145e28379775@r25g2000vbn.googlegroups.com>

On Jul 27, 2:25?pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 27, 5:11?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
>
> > Hi,
> > ? ? I am facing a problem using PyArg_ParseTuple() in my C-API
> > extension. Here is a small repro of the function:
>
> > static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> > {
> > ? ? ? ? SQLUSMALLINT param_no = 0;
>
> Sorry, my crystal ball is on the fritz. What is SQLUSMALLINT on
> Windows/Linux/AIX?
> What does
> ? ? printf("%d %d %d\n", sizeof(SQLUSMALLINT), sizeof(int), sizeof
> (long));
> give you on each platform?
>
> > ? ? ? ? PyObject *py_obj = NULL;
>
> > ? ? ? ? if (!PyArg_ParseTuple(args, "Oi", &py_obj, &param_no)){
>
> > ? ? ? ? ? ? ? ? return NULL;
> > ? ? ? ? }
> > ? ? ? ? printf("%d\n", param_no);
> > ? ? ? ? return NULL;
>
> > }
>
> > This function works fine and prints the correct value passed
> > (param_no) when I test it on Linux or Windows. However, it always
> > prints 0 (initial value defined in function) when I run it on AIX.
>
> Consider that 0 could have been plucked out of the air and has nothing
> to do with the initial value of param_no. Try initialising it to
> something distinctive, like 0xfedcba98. Use %08x format in the printf
> rather than %d.
>
>
>
> > I think the problem is with "Oi" argument, if I replace that with "OO"
> > and specifically convert it integer/sqlsmallint. It works fine on AIX,
> > but I want to use "i" and not "O".
>
> > Any ideas on what is the reason behind the problem and how to fix
> > this?
>
> I jump-started the crystal ball from the over-head tram wire and saw
> this: """SQLSMALLINT is 16 bits on all platforms, int/long is 32 bits
> on all platforms, first 2 are little-endian, AIX is bigendian, the "i"
> format expects SIGNED int /long, so param_no is getting (win:x,
> linux:x, aix:0) and the next 16 bits in memory are getting trashed
> with (win:0, linux:0, aix:x) (when x is your input smallish integer)
> and luckily this trashing didn't cause a crash. You can receive the
> result from the function in an int/long then have code to reject it if
> it won't fit into a SQLUSMALLINT, and cast it otherwise. If you don't
> care about overflow (NOT recommended), just use "H" format instead if
> "i" format"""
>
> Could be wrong, really shouldn't subject precision instruments to 415V
> DC, only OPs :-)
>
> N.B. to detect endianness : use print sys.byteorder
>
> HTH,
> John

Hi,
    Thanks for the response. If I don't use SQLUSMALLINT and use int
instead, then also I see the same problem.
static PyObject *parsetuple_test(PyObject *self, PyObject *args)
 {
        int param_no = 0;
....
....
}
This also prints out 0 for AIX and actual value passed in other
platforms. If I initialize param_no with some other value (e.g. 90),
it prints out that value.

-
Abhigyan


From piet at cs.uu.nl  Mon Jul 27 07:08:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 13:08:27 +0200
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com>
Message-ID: <m2skgibcyc.fsf@cs.uu.nl>

>>>>> Paul Rubin <http://phr.cx at NOSPAM.invalid> (PR) wrote:

>PR> Rob Knop <rknop at pobox.com> writes:
>>> Are there any python libraries that will take a public key in this
>>> format and do RSA encoding on it?

>PR> Try www.trevp.com/tlslite

I have looked into tlslite and found no easy way to do this. Maybe I
overlooked it. On the other hand with M2Crypto it isn't that hard.

However, M2Crypto wants to load keys in PEM format rather than the DER
format that the Java getEncoded() produces. It is not hard to convert
this to PEM format: just Base64 encode it and put a header and trailer
line around it. The conversion can be done with openssl or just on the
fly in the Python code.
Please note that the text to be encrypted must be smaller than the key
size (at least 11 bytes smaller). You shouldn't encrypt large data with
RSA anyway: it is too slow. Normally you would encrypt a session key
with RSA and encrypt the data with the session key using a symmetric
algorithms like AES.

Here is an example script:
If your OS doesn't have /dev/urandom you should probably seed OpenSSL's
PRNG to be more secure.
------------------------------------------------------------------------
from M2Crypto import BIO, RSA

pubkey = open("pubkey.der", 'rb').read()

import base64
pubkey = base64.encodestring(pubkey)
pubkey = '-----BEGIN PUBLIC KEY-----\n' + pubkey + '-----END PUBLIC KEY-----'

bio = BIO.MemoryBuffer(pubkey)
rsa = RSA.load_pub_key_bio(bio)

plaintext = "This is my secret text."

codetext = rsa.public_encrypt(plaintext, RSA.pkcs1_padding)

with open("codetext", 'wb') as out:
    out.write(codetext)
------------------------------------------------------------------------
The following Java program decodes this with the corresponding private
key:
------------------------------------------------------------------------
import java.security.*;
import javax.crypto.*;
import java.security.spec.*;
import java.security.interfaces.*;
import java.io.*;

class Decrypt {

    public static void main(String[] args) {      

        byte[] key = null;
        try {
            File file = new File("privkey.der");
            FileInputStream keyfile = new FileInputStream(file);
            key = new byte[(int)file.length()];
            DataInputStream dis= new DataInputStream(keyfile);
            dis.readFully(key);
            dis.close();
        }
        catch(FileNotFoundException e)
        {
            System.out.println("Key file not found" + e);
        }
        catch (IOException e) {
            System.out.println("Can't read key file" + e);
        }

        byte[] codetext = null;
        try {
            File file = new File("codetext");
            FileInputStream codefile = new FileInputStream(file);
            codetext = new byte[(int)file.length()];

            DataInputStream dis = new DataInputStream(codefile);
            dis.readFully(codetext);
            dis.close();
        }
        catch(FileNotFoundException e)
        {
            System.out.println("Code file not found" + e);
        }
        catch (IOException e) {
            System.out.println("Can't read code file" + e);
        }

        try {

            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            
            PKCS8EncodedKeySpec privSpec = new PKCS8EncodedKeySpec(key);
            RSAPrivateKey rsakey = (RSAPrivateKey) keyFactory.generatePrivate(privSpec);

            Cipher c = Cipher.getInstance("RSA/ECB/PKCS1Padding");

            c.init(Cipher.DECRYPT_MODE, rsakey);
            byte[] decrypted = c.doFinal(codetext);
            System.out.println("Decrypted text:");
            System.out.println(new String(decrypted));

        }
        catch (NoSuchAlgorithmException e) {
            System.out.println("Wrong Algorithm " + e);
        }   
        catch (InvalidKeyException e) {
            System.out.println("Invalid key " + e);
        }   
        catch (IllegalBlockSizeException e) {
            System.out.println("Illegal block size" + e);
        }   
        catch (NoSuchPaddingException e) {
            System.out.println("Illegal padding " + e);
        }   
        catch (BadPaddingException e) {
            System.out.println("Bad padding " + e);
        }   
        catch (InvalidKeySpecException e) {
            System.out.println("Invalid keyspec " + e);
        }   
    }
}
------------------------------------------------------------------------
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From sean.kemplay at gmail.com  Mon Jul 27 07:14:10 2009
From: sean.kemplay at gmail.com (Sean Kemplay)
Date: Mon, 27 Jul 2009 04:14:10 -0700 (PDT)
Subject: Free hosting for open source Python projects
Message-ID: <97378723-7e67-415b-84bb-06d1675f2e2b@n11g2000yqb.googlegroups.com>

Hi All,

If anyone is looking for somewhere to host their Python project /
modules etc. for free,  please get in touch with me.  There of course
are some restraints on disk space and bandwidth but they should be
sufficient for most projects.  Your project must be open source.

You will have access to both Django or Plone/Zope(shared).  No PHP etc
- this is a Python only host.

Unfortunately I can't host everyone but if I can't host your
particular project now, I may be able to at a later stage.

Please contact me at "postmaster (at) pythonicity.co.uk".  Our website
is located at www.pythonicity.co.uk if you want to see what we do.

Best Regards,
Sean Kemplay



From wilk at flibuste.net  Mon Jul 27 07:16:15 2009
From: wilk at flibuste.net (William Dode)
Date: 27 Jul 2009 11:16:15 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<b0afe5f7-0cd9-43af-ba1e-0e405d5ceb5f@h21g2000yqa.googlegroups.com>
Message-ID: <4a6d8c7f$0$19614$426a74cc@news.free.fr>

On 27-07-2009, Bearophile wrote:
> William Dode':
>> I updated the script (python, c and java) with your unrolled version
>> + somes litle thinks.
> [...]
>> c 1.85s
>> gcj 2.15s
>> java 2.8s
>> python2.5 + psyco 3.1s
>> unladen-2009Q2 145s (2m45)
>> python2.5 254s (4m14s)
>> python3.1 300s (5m)
>> ironpython1.1.1 680s (11m20)
>
> Sorry for being late, I was away.
>
> In your last C version this code is useless because the C compiler is
> able to perform such simple optimization by itself (but probably
> Python isn't able, so if you want the code to be the similar in all
> versions it may be better to keep it):

I wanted so, specialy if it doesn't change a lot of the result (the 
difference is so small that i cannot see it)...

...

> I have tried your latest C version using your compiler options, my
> MinGW based on GCC 4.3.2 produces a crash at runtime.

Maybe because of -msse2 ?

> Using LLVM-GCC
> it runs in 1.31 seconds. The D version is a bit less optimized than
> your last C versions, yet using DMD it runs in 1.08-1.10 seconds.
> Let's see if someone is able to write a C version faster than that D
> code :-)
>
> Have you have compiled/read my D version? In the D version you may
> have missed that I did use an extra trick: unsigned integers, so it
> needs just two tests to see if a number is in the 0-5, 0-5 square :-)

I didn't see, fine ! But the difference is also too small to see...

> Note that Pyd, the Python-D bridge, may work with the latest DMD
> version still (and it works if you use a bit older DMD compiler):
> http://pyd.dsource.org/

I completly don't know anything about D... When i see the result of 
psyco or shedskin, i'm affraid i'll not look somewhere else soon !

However, i'd like to see a lisp implementation of this...

bye

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From davea at ieee.org  Mon Jul 27 07:21:44 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 07:21:44 -0400
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
In-Reply-To: <f2e7a4240907270033g277018a0oe687025ffdd2c083@mail.gmail.com>
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>	
	<4A69A82D.8090301@ieee.org>
	<f2e7a4240907270033g277018a0oe687025ffdd2c083@mail.gmail.com>
Message-ID: <4A6D8DC8.40304@ieee.org>

(forwarding this message, as the reply was off-list)
Kim Hansen wrote:
> 2009/7/24 Dave Angel <davea at ieee.org>:
>   
>> It's not a question of how much disk space there is, but how much virtual
>> space 32 bits can address.  2**32 is about 4 gig, and Windows XP reserves
>> about half of that for system use.  Presumably a 64 bit OS would have a much
>> larger limit.
>>
>> Years ago I worked on Sun Sparc system which had much more limited shared
>> memory access, due to hardware limitations.  So 2gig seems pretty good to
>> me.
>>
>> There is supposed to be a way to tell the Windows OS to only use 1 gb of
>> virtual space, leaving 3gb for application use.  But there are some
>> limitations, and I don't recall what they are.  I believe it has to be done
>> globally (probably in Boot.ini), rather than per process.  And some things
>> didn't work in that configuration.
>>
>> DaveA
>>
>>
>>     
> Hi Dave,
>
> In the related post I did on the numpy discussions:
>
> http://article.gmane.org/gmane.comp.python.numeric.general/31748
>
> another user was kind enough to run my test program on both 32 bit and
> 64 bit machines. On the 64 bit machine, there was no such limit, very
> much in line with what you wrote. Adding the /3GB option in boot.ini
> did not increase the available memory as well. Apparently, Python
> needs to have been compiled in a way, which makes it possible to take
> advantage of that switch and that is either not the case or I did
> something else wrong as well.
>
> I acknowledge the explanation concerning the address space available.
> Being an ignorant of the inner details of the implementation of mmap,
> it seems like somewhat an "implementation detail" to me that such an
> address wall is hit. There may be some good arguments from a
> programming point of view and it may be a relative high limit as
> compared to other systems but it is certainly at the low side for my
> application: I work with data files typically 200 GB in size
> consisting of datapackets each having a fixed size frame and a
> variable size payload. To handle these large files, I generate an
> "index" file consisting of just the frames (which has all the metadata
> I need for finding the payloads I am interested in) and "pointers" to
> where in the large data file each payload begins. This index file can
> be up to 1 GB in size and at times I need to have access to two of
> those at the same time (and then i hit the address wall). I would
> really really like to be able to access these index files in a
> read-only manner as an array of records on a file for which I use
> numpy.memmap (which wraps mmap.mmap) such that I can pick a single
> element, extract, e.g., every thousand value of a specific field in
> the record using the convenient indexing available in Python/numpy.
> Now it seems like I have to resort to making my own encapsulation
> layer, which seeks to the relevant place in the file, reads sections
> as bytestrings into recarrays, etc. Well, I must just get on with
> it...
>
> I think it would be worthwhile specifying this 32 bit OS limitation in
> the documentation of mmap.mmap, as I doubt I am the only one being
> surprised about this address space limitation.
>
> Cheers,
> Kim
>
>   
I agree that some description of system limitations should be included 
in a system-specific document.  There probably is one, I haven't looked 
recently.  But I don't think it belongs in mmap documentation.

Perhaps you still don't recognize what the limit is.  32 bits can only 
address 4 gigabytes of things as first-class addresses.  So roughly the 
same limit that's on mmap is also on list, dict, bytearray, or anything 
else.  If you had 20 lists taking 100 meg each, you would fill up 
memory.  If you had 10 of them, you might have enough room for a 1gb 
mmap area.  And your code takes up some of that space, as well as the 
Python interpreter, the standard library, and all the data structures 
that are normally ignored by the application developer.

BTW,  there is one difference between mmap and most of the other 
allocations.  Most data is allocated out of the swapfile, while mmap is 
allocated from the specified file (unless you use -1 for fileno).  
Consequently, if the swapfile is already clogged with all the other 
running applications, you can still take your 1.8gb or whatever of your 
virtual space, when much less than that might be available for other 
kinds of allocations.

Executables and dlls are also (mostly) mapped into memory just the same 
as mmap.  So they tend not to take up much space from the swapfile.  In 
fact, with planning, a DLL needn't take up any swapfile space (well, a 
few K is always needed, realistically)..  But that's a linking issue for 
compiled languages.

DaveA



From mdekauwe at gmail.com  Mon Jul 27 07:24:31 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 04:24:31 -0700 (PDT)
Subject: quickly looping over a 2D array?
Message-ID: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>

Hi,

I am new to python and I was wondering if there was a way to speed up
the way I index 2D arrays when I need to check two arrays
simultaneously? My current implementations is (using numpy) something
like the following...

for i in range(numrows):
    for j in range(numcols):

        if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
j] * some_other_value
            array_1[i, j] = some_new_value

Many Thanks,

Martin


From michael at stroeder.com  Mon Jul 27 07:35:15 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Mon, 27 Jul 2009 13:35:15 +0200
Subject: RSA cryptography between Python and Java
In-Reply-To: <m2skgibcyc.fsf@cs.uu.nl>
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com> <m2skgibcyc.fsf@cs.uu.nl>
Message-ID: <j0g0k6-i65.ln1@nb2.stroeder.com>

Piet van Oostrum wrote:
> Please note that the text to be encrypted must be smaller than the key
> size (at least 11 bytes smaller). You shouldn't encrypt large data with
> RSA anyway: it is too slow. Normally you would encrypt a session key
> with RSA and encrypt the data with the session key using a symmetric
> algorithms like AES.

I'd use CMS (AKA PKCS#7) for encrypted/signed data with X.509 certs. One
should not invent another message format.

Ciao, Michael.

-- 
Michael Str?der
E-Mail: michael at stroeder.com
http://www.stroeder.com


From __peter__ at web.de  Mon Jul 27 07:42:48 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 13:42:48 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
Message-ID: <h4k3ro$719$00$1@news.t-online.com>

Martin wrote:

> I am new to python and I was wondering if there was a way to speed up
> the way I index 2D arrays when I need to check two arrays
> simultaneously? My current implementations is (using numpy) something
> like the following...
> 
> for i in range(numrows):
>     for j in range(numcols):
> 
>         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
> j] * some_other_value
>             array_1[i, j] = some_new_value

array_1[(array_1 == some_value) | (array_2 >= array_1 * some_other_value)] = 
some_new_value

maybe?



From nogetfx at gmail.com  Mon Jul 27 07:48:30 2009
From: nogetfx at gmail.com (Lars)
Date: Mon, 27 Jul 2009 04:48:30 -0700 (PDT)
Subject: Call function from another class
References: <4b6b0e4b-b85b-43cf-a695-e3a722de01cc@e11g2000yqo.googlegroups.com>
	<7d5em2F2anm94U1@mid.uni-berlin.de>
Message-ID: <f8fd35e5-1307-4957-8f28-002068d42637@t13g2000yqt.googlegroups.com>

> If I'm not mistaken, in "doRotate" you should be able to refer to the
> to-be-closed dialog via
> self.frameRotate
>
> Now if you change the "sliderUpdate"-code to store that angle instead of
> just letting it fall out of scope, you could access that value through
> frameRotate:
>
> def sliderUpdate(self, event):
> ? ? ? ? angle=self.slider.GetValue()
> ? ? ? ? ROTATION_ANGLE=angle
> ? ? ? ? self.angle = angle
> ? ? ? ? self.Destroy()
>
> def doRotate(self,event):
> ? ? """Rotating image"""
> ? ? print self.frameRotate.angle

Thanks for replying. If Bind is used in "onRotate":
def onRotate(self,event):
       """Rotate image"""
       self.frameRotate = rotationSlider(parent=None, id=-1)
       self.Bind(wx.EVT_CLOSE,self.doRotate, self.frameRotate.Destroy)
       self.frameRotate.Show()

Then i get:
Traceback (most recent call last):
  File "viewer_sep.py", line 136, in onRotate
    self.Bind(wx.EVT_CLOSE,self.doRotate, self.frameRotate.Destroy)
  File "/usr/lib/python2.5/site-packages/wx-2.6-gtk2-unicode/wx/
_core.py", line 3629, in Bind
    id  = source.GetId()
AttributeError: 'function' object has no attribute 'GetId'

My experience with ID is setting it to "-1".  So I'm not sure if it is
a wrong use of Bind or an wxPython error.
/Lars


From Slaunger at gmail.com  Mon Jul 27 07:50:52 2009
From: Slaunger at gmail.com (Slaunger)
Date: Mon, 27 Jul 2009 04:50:52 -0700 (PDT)
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
	<4A69A82D.8090301@ieee.org>
	<f2e7a4240907270033g277018a0oe687025ffdd2c083@mail.gmail.com> 
	<mailman.3767.1248693717.8015.python-list@python.org>
Message-ID: <ca1180e7-1f20-492d-9edb-ba9e04bcecc3@h11g2000yqb.googlegroups.com>

On 27 Jul., 13:21, Dave Angel <da... at ieee.org> wrote:
> (forwarding this message, as the reply was off-list)
>
>
>
> Kim Hansen wrote:
> > 2009/7/24 Dave Angel <da... at ieee.org>:
>
> >> It's not a question of how much disk space there is, but how much virtual
> >> space 32 bits can address. ?2**32 is about 4 gig, and Windows XP reserves
> >> about half of that for system use. ?Presumably a 64 bit OS would have a much
> >> larger limit.
>
> >> Years ago I worked on Sun Sparc system which had much more limited shared
> >> memory access, due to hardware limitations. ?So 2gig seems pretty good to
> >> me.
>
> >> There is supposed to be a way to tell the Windows OS to only use 1 gb of
> >> virtual space, leaving 3gb for application use. ?But there are some
> >> limitations, and I don't recall what they are. ?I believe it has to be done
> >> globally (probably in Boot.ini), rather than per process. ?And some things
> >> didn't work in that configuration.
>
> >> DaveA
>
> > Hi Dave,
>
> > In the related post I did on the numpy discussions:
>
> >http://article.gmane.org/gmane.comp.python.numeric.general/31748
>
> > another user was kind enough to run my test program on both 32 bit and
> > 64 bit machines. On the 64 bit machine, there was no such limit, very
> > much in line with what you wrote. Adding the /3GB option in boot.ini
> > did not increase the available memory as well. Apparently, Python
> > needs to have been compiled in a way, which makes it possible to take
> > advantage of that switch and that is either not the case or I did
> > something else wrong as well.
>
> > I acknowledge the explanation concerning the address space available.
> > Being an ignorant of the inner details of the implementation of mmap,
> > it seems like somewhat an "implementation detail" to me that such an
> > address wall is hit. There may be some good arguments from a
> > programming point of view and it may be a relative high limit as
> > compared to other systems but it is certainly at the low side for my
> > application: I work with data files typically 200 GB in size
> > consisting of datapackets each having a fixed size frame and a
> > variable size payload. To handle these large files, I generate an
> > "index" file consisting of just the frames (which has all the metadata
> > I need for finding the payloads I am interested in) and "pointers" to
> > where in the large data file each payload begins. This index file can
> > be up to 1 GB in size and at times I need to have access to two of
> > those at the same time (and then i hit the address wall). I would
> > really really like to be able to access these index files in a
> > read-only manner as an array of records on a file for which I use
> > numpy.memmap (which wraps mmap.mmap) such that I can pick a single
> > element, extract, e.g., every thousand value of a specific field in
> > the record using the convenient indexing available in Python/numpy.
> > Now it seems like I have to resort to making my own encapsulation
> > layer, which seeks to the relevant place in the file, reads sections
> > as bytestrings into recarrays, etc. Well, I must just get on with
> > it...
>
> > I think it would be worthwhile specifying this 32 bit OS limitation in
> > the documentation of mmap.mmap, as I doubt I am the only one being
> > surprised about this address space limitation.
>
> > Cheers,
> > Kim
>
> I agree that some description of system limitations should be included
> in a system-specific document. ?There probably is one, I haven't looked
> recently. ?But I don't think it belongs in mmap documentation.
>
> Perhaps you still don't recognize what the limit is. ?32 bits can only
> address 4 gigabytes of things as first-class addresses. ?So roughly the
> same limit that's on mmap is also on list, dict, bytearray, or anything
> else. ?If you had 20 lists taking 100 meg each, you would fill up
> memory. ?If you had 10 of them, you might have enough room for a 1gb
> mmap area. ?And your code takes up some of that space, as well as the
> Python interpreter, the standard library, and all the data structures
> that are normally ignored by the application developer.
>
> BTW, ?there is one difference between mmap and most of the other
> allocations. ?Most data is allocated out of the swapfile, while mmap is
> allocated from the specified file (unless you use -1 for fileno). ?
> Consequently, if the swapfile is already clogged with all the other
> running applications, you can still take your 1.8gb or whatever of your
> virtual space, when much less than that might be available for other
> kinds of allocations.
>
> Executables and dlls are also (mostly) mapped into memory just the same
> as mmap. ?So they tend not to take up much space from the swapfile. ?In
> fact, with planning, a DLL needn't take up any swapfile space (well, a
> few K is always needed, realistically).. ?But that's a linking issue for
> compiled languages.
>
> DaveA- Skjul tekst i anf?rselstegn -
>
> - Vis tekst i anf?rselstegn -

I do understand the 2 GB address space limitation. However, I think I
have found a solution to my original numpy.memmap problem (which spun
off to this problem), and that is PyTables, where I can address 2^64
data on a 32 bit machine using hd5 files and thus circumventing the
"implementation detail" of the intermedia 2^32 memory address problem
in the numpy.memmap/mmap.mmap implementation.

http://www.pytables.org/moin

I just watched the first tutorial video, and that seems like just what
I am after (if it works as well in practise at it appears to do).

http://showmedo.com/videos/video?name=1780000&fromSeriesID=178

Cheers,
Kim


From piet at cs.uu.nl  Mon Jul 27 07:51:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 13:51:34 +0200
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
Message-ID: <m2ocr6bayh.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()

By the way, a PEM file is a text file, no reason to open it in binary
mode. Just replace the 'rb' with 'r' or leave it out.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 27 08:19:49 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 14:19:49 +0200
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com> <m2skgibcyc.fsf@cs.uu.nl>
	<j0g0k6-i65.ln1@nb2.stroeder.com>
Message-ID: <m2fxcib9ne.fsf@cs.uu.nl>

>>>>> Michael Str?der <michael at stroeder.com> (MS) wrote:

>MS> Piet van Oostrum wrote:
>>> Please note that the text to be encrypted must be smaller than the key
>>> size (at least 11 bytes smaller). You shouldn't encrypt large data with
>>> RSA anyway: it is too slow. Normally you would encrypt a session key
>>> with RSA and encrypt the data with the session key using a symmetric
>>> algorithms like AES.

>MS> I'd use CMS (AKA PKCS#7) for encrypted/signed data with X.509 certs. One
>MS> should not invent another message format.

Yes but the original question was not about X.509 certs. Just the RSA
public key. I don't know what the OP wants to do with it.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From drobinow at gmail.com  Mon Jul 27 08:20:48 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 27 Jul 2009 07:20:48 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4A6CC3BE.6060806@mrabarnett.plus.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<4A6CC3BE.6060806@mrabarnett.plus.com>
Message-ID: <4eb0089f0907270520n782503b1ndc34bcb1cf14a47e@mail.gmail.com>

On 7/26/09, MRAB <python at mrabarnett.plus.com> wrote:
> David Robinow wrote:
> > > This doesn't mean they're on the same level - in fact, if you read
> carefully
> > > you'll see my original post said as much: python attracted average
> > > programmers; php attracted mediocre programmers and even some
> > > non-programmers, which means that php is clearly a lesser language than
> > > python.
> >  I'm a mediocre programmer. Does this mean I should switch to PHP?
> If you're a mediocre programmer who knows you're mediocre, but wants to
> improve and is willing to learn, then stick with Python. You'll get
> better. :-)
I doubt it. I remember when Guido moved to the U.S. and I've even used
stdwin. I've actually gotten worse over the years. Old age does that.
Nevertheless, I question the idea that a language that is easy to use
(I don't know if PHP qualifies) is somehow inferior.


From mdekauwe at gmail.com  Mon Jul 27 08:27:11 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 05:27:11 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
Message-ID: <503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>

On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > I am new to python and I was wondering if there was a way to speed up
> > the way I index 2D arrays when I need to check two arrays
> > simultaneously? My current implementations is (using numpy) something
> > like the following...
>
> > for i in range(numrows):
> >     for j in range(numcols):
>
> >         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
> > j] * some_other_value
> >             array_1[i, j] = some_new_value
>
> array_1[(array_1 == some_value) | (array_2 >= array_1 * some_other_value)] =
> some_new_value
>
> maybe?

So I tried...

band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0

which led to

ValueError: The truth value of an array with more than one element is
ambiguous. Use a.any() or a.all()

so not sure that works?


From rlichlighter at gmail.com  Mon Jul 27 08:29:23 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 05:29:23 -0700 (PDT)
Subject: Convert raw binary file to ascii
Message-ID: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>

I have a memory dump from a machine I am trying to analyze. I can view
the file in a hex editor to see text strings in the binary code. I
don't see a way to save these ascii representations of the binary, so
I went digging into Python to see if there were any modules to help.

I found one I think might do what I want it to do - the binascii
module. Can anyone describe to me how to convert a raw binary file to
an ascii file using this module. I've tried? Boy, I've tried.

Am I correct in assuming I can get the converted binary to ascii text
I see in a hex editor using this module? I'm new to this forensics
thing and it's quite possible I am mixing technical terms. I am not
new to Python, however. Thanks for your help.


From electriclightheads at gmail.com  Mon Jul 27 08:29:58 2009
From: electriclightheads at gmail.com ('2+)
Date: Mon, 27 Jul 2009 21:29:58 +0900
Subject: wave.setparams((2, 2, 44100, 44100 * 2 * 10, "NONE", "not 
	compressed")) became more than 30secs
Message-ID: <1078018b0907270529l676fdb75k4c1f42ef0a2e7d0a@mail.gmail.com>

thanx to rob .. who gave me an example of how to use the WAVE lib
now am on my way to use it as simple as i can

i wrote an oil.py the instance of which will behave like an oscillator
which constantly generates 7 different wave forms (non fixed)
i thought this code might produce 10secs of wave file but the result
was longer than 30secs
was testing if i could use the WAVE lib withount taking advantage of
StringIO
nor
struct
but maybe am doing totally wrong?

--8<---

import oil
import wave

a = oil.Sa()

w = wave.open("current.wav", "w")
w.setparams((2, 2, 44100, 44100 * 2 * 10, "NONE", "not compressed"))

for gas in range(44100 * 10):
    a.breath()
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    w.writeframes(hex(r))
    w.writeframes(hex(l))
w.close()



-- 
SaRiGaMa's Oil Vending Orchestra
is podcasting:
http://sarigama.namaste.jp/podcast/rss.xml
and supplying oil.py for free:
http://oilpy.blogspot.com/


From benjamin.kaplan at case.edu  Mon Jul 27 08:41:23 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Mon, 27 Jul 2009 08:41:23 -0400
Subject: Help understanding the decisions *behind* python? - immutable 
	objects
In-Reply-To: <4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
Message-ID: <ec96e1390907270541p7846d649r7d8fd6e429c64a56@mail.gmail.com>

On Sun, Jul 26, 2009 at 2:24 PM, John Nagle<nagle at animats.com> wrote:
> Beni Cherniavsky wrote:
>>
>> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
>> wrote:
>>>
>>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>>
>>>> My guess is that it was probably for optimization reasons long ago.
>>>> I've never heard a *good* reason why Python needs both.
>>>
>>> The good reason is the immutability, which lets you use
>>> a tuple as a dict key.
>>
>> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
>> wrote:
>>>
>>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>>
>>>> My guess is that it was probably for optimization reasons long ago.
>>>> I've never heard a *good* reason why Python needs both.
>>>
>>> The good reason is the immutability, which lets you use
>>> a tuple as a dict key.
>>>
>> The *technical* reason is immutability for dict keys.
>> Dict could allow mutable objects as keys by comparing *by value*,
>> making a copy on insertion and hashing the current value on lookup.
>> Prior art: the 2.3 sets module allows mutable Sets as elements in
>> Sets, by making ImmutableSet copies on insertion, and hashing Sets as
>> if they are temporarily immutable on lookup.
>>
>> This inspired PEP 351 and ambitious proposals to expand the approach
>> to all Python with a copy-on-write scheme. ?But these ideas were
>> rejected, and the 2.4 builtin sets only allow frozenset elements.
>> Half the reason is technical: copy-on-write and harder than it sounds,
>> and without it you pay a performance price.
>>
>> But the deeper reason is style: immutable types are convenient!
>> The allow a pure-functional style of code, which can be simpler.
>> Of course, sometimes an imperative style is simpler. ?Depends on the
>> problem.
>
> ? ?An interesting issue is Python objects, which are always mutable.
> A "dict" of Python objects is allowed, but doesn't consider
> the contents of the objects, just their identity (address). Only
> built-in types are immutable; one cannot create a class of immutable
> objects.
> So things like "frozenset" had to be built into the language.
> A tuple is really a frozen list. ?Arguably, frozen objects
> should have been a general concept. ?Conceptually, they're
> simple - once "__init__" has run, there can be no more changes
> to fields of the object.
>
> ? ?Compare the C++ approach, where you can have a "map" of
> any object that defines the "<" operator. ?Python has
> "__cmp__" for objects, but built-in dictionaries don't use it.
> Of course, one could create a "map" class in Python that
> uses "__cmp__", which would allow dictionary-type operations
> on arbitrary objects.


Python dictionaries are hash maps so they use hashes, not comparisons,
to store objects. By default the hash is equal to the object's
identity but all you need to do to change it is define your own
__hash__ method. If you were to make a C++ hash map, it wouldn't use
comparisons either.


>
> ? ?There are some interesting uses for immutable objects in
> multithreaded programs. ?They can be shared between threads
> without locking. ?If it weren't for the infamous Global
> Interpreter Lock, which basically limits Python programs to using
> one CPU at a time, Python would have to deal with locking
> in a more advanced way. ?A system where immutable objects
> can be shared and passed between threads, and mutable objects
> must be "synchronized" (in the Java sense) to be shared would
> be useful.
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?John Nagle
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From rashidsdpk at gmail.com  Mon Jul 27 08:45:33 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Mon, 27 Jul 2009 05:45:33 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <d6433b12-1c85-4cca-a1ec-6abcab8c0d62@s31g2000yqs.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.more http://0nanotechnology0.blogspot.com/


From __peter__ at web.de  Mon Jul 27 08:46:54 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 14:46:54 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
Message-ID: <h4k7jt$ec1$00$1@news.t-online.com>

Martin wrote:

> On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
>> Martin wrote:
>> > I am new to python and I was wondering if there was a way to speed up
>> > the way I index 2D arrays when I need to check two arrays
>> > simultaneously? My current implementations is (using numpy) something
>> > like the following...
>>
>> > for i in range(numrows):
>> >     for j in range(numcols):
>>
>> >         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
>> > j] * some_other_value
>> >             array_1[i, j] = some_new_value
>>
>> array_1[(array_1 == some_value) | (array_2 >= array_1 *
>> some_other_value)] = some_new_value
>>
>> maybe?
> 
> So I tried...
> 
> band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
> 
> which led to
> 
> ValueError: The truth value of an array with more than one element is
> ambiguous. Use a.any() or a.all()
> 
> so not sure that works?

Copy and paste -- or replace "or" with "|".



From mdekauwe at gmail.com  Mon Jul 27 08:55:15 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 05:55:15 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
Message-ID: <266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>

On Jul 27, 1:46 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
> >> Martin wrote:
> >> > I am new to python and I was wondering if there was a way to speed up
> >> > the way I index 2D arrays when I need to check two arrays
> >> > simultaneously? My current implementations is (using numpy) something
> >> > like the following...
>
> >> > for i in range(numrows):
> >> >     for j in range(numcols):
>
> >> >         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
> >> > j] * some_other_value
> >> >             array_1[i, j] = some_new_value
>
> >> array_1[(array_1 == some_value) | (array_2 >= array_1 *
> >> some_other_value)] = some_new_value
>
> >> maybe?
>
> > So I tried...
>
> > band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
>
> > which led to
>
> > ValueError: The truth value of an array with more than one element is
> > ambiguous. Use a.any() or a.all()
>
> > so not sure that works?
>
> Copy and paste -- or replace "or" with "|".

apologies - I mistook that for a type for "or"

I now get the following error...

ValueError: shape mismatch: objects cannot be broadcast to a single
shape


From __peter__ at web.de  Mon Jul 27 09:06:17 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 15:06:17 +0200
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
Message-ID: <h4k8o8$ght$00$1@news.t-online.com>

r2 wrote:

> I have a memory dump from a machine I am trying to analyze. I can view
> the file in a hex editor to see text strings in the binary code. I
> don't see a way to save these ascii representations of the binary, so
> I went digging into Python to see if there were any modules to help.
> 
> I found one I think might do what I want it to do - the binascii
> module. Can anyone describe to me how to convert a raw binary file to
> an ascii file using this module. I've tried? Boy, I've tried.

That won't work because a text editor doesn't need any help to convert the 
bytes into characters. If it expects ascii it just will be puzzled by bytes 
that are not valid ascii. Also, it will happily display byte sequences that 
are valid ascii, but that you as a user will see as gibberish because they 
were meant to be binary data by the program that wrote them.

> Am I correct in assuming I can get the converted binary to ascii text
> I see in a hex editor using this module? I'm new to this forensics
> thing and it's quite possible I am mixing technical terms. I am not
> new to Python, however. Thanks for your help.

Unix has the "strings" commandline tool to extract text from a binary.
Get hold of a copy of the MinGW tools if you are on windows.

Peter



From nemelis at gmail.com  Mon Jul 27 09:12:39 2009
From: nemelis at gmail.com (Harry Ebbers)
Date: Mon, 27 Jul 2009 06:12:39 -0700 (PDT)
Subject: Testoob: How do you use testoob.collector_from_globals / 
	collector_from_modules?
Message-ID: <1a8582cc-a7fc-4b1e-b1b2-d23e20ad6022@18g2000yqa.googlegroups.com>

Hi,

For a project I'm creating unittests using testoob. When all tests are
in a single file there is no problem

if __name__ == '__main__':
    testoob.main()
 does the trick as usual.

But for a number of python-applications they have asked me to group
unittests in different files, based on common functionality (e.g. GUI,
main-application, etcetera).

Ican get it to work by importing all unittestclasses in the following
way and than use the normal if __name__ == '__main__' construction

(from GUI import GUItests
from APP import APPtests

if __name__ == '__main__':
    testoob.main())

But looking at the future I would like to use testsuites.

On the internet I found the functions testoob.collector_from_globals
and collector_from_modules which one can use to 'easily' create
testsuites which can be used with testoob. But no examples on how to
use them can be found.

Can anybody supply me with a working example?

TIA

Harry Ebbers


From __peter__ at web.de  Mon Jul 27 09:17:58 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 15:17:58 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
Message-ID: <h4k9e6$tf9$02$1@news.t-online.com>

Martin wrote:

> On Jul 27, 1:46 pm, Peter Otten <__pete... at web.de> wrote:
>> Martin wrote:
>> > On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
>> >> Martin wrote:
>> >> > I am new to python and I was wondering if there was a way to speed
>> >> > up the way I index 2D arrays when I need to check two arrays
>> >> > simultaneously? My current implementations is (using numpy)
>> >> > something like the following...
>>
>> >> > for i in range(numrows):
>> >> >     for j in range(numcols):
>>
>> >> >         if array_1[i, j] == some_value or array_2[i, j] >=
>> >> >         array_1[i,
>> >> > j] * some_other_value
>> >> >             array_1[i, j] = some_new_value
>>
>> >> array_1[(array_1 == some_value) | (array_2 >= array_1 *
>> >> some_other_value)] = some_new_value
>>
>> >> maybe?
>>
>> > So I tried...
>>
>> > band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
>>
>> > which led to
>>
>> > ValueError: The truth value of an array with more than one element is
>> > ambiguous. Use a.any() or a.all()
>>
>> > so not sure that works?
>>
>> Copy and paste -- or replace "or" with "|".
> 
> apologies - I mistook that for a type for "or"
> 
> I now get the following error...
> 
> ValueError: shape mismatch: objects cannot be broadcast to a single
> shape

It seems array_1 and array_2 have a -- dada! -- different shape.
Assuming array_1 is the smaller one:

numrows, numcols = array_1.shape
array_1[(array_1 == some_value) | (array_2[:numrows,:numcols] >= array_1 * 
some_other_value)] = some_new_value

There may be other options, but I'm not a numpy expert.

Peter



From constant.beta at gmail.com  Mon Jul 27 09:46:01 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Mon, 27 Jul 2009 06:46:01 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<mailman.3715.1248552511.8015.python-list@python.org>
	<2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>
	<h4iqgb$ss5$1@panix3.panix.com>
Message-ID: <1c8ae01e-2e9c-497c-9f8d-408f56f9c0bd@g31g2000yqc.googlegroups.com>

On Jul 27, 1:56 am, a... at pythoncraft.com (Aahz) wrote:
> >> Upon a cursory look, after a generator 'gen' is exhausted (meaning
> >> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
> >> None.
>
> >Only in Python 2.5 or higher though. I need to support Python 2.3 and
> >2.4 as well, sorry for not making that clear in the original post.
>
> Are you sure?  It appears to work in Python 2.4; I don't have time to
> check 2.3.

No, it does not work in Python 2.4. gi_frame can be None only in
Python 2.5 and higher.

Via "What?s New in Python 2.5" (http://docs.python.org/whatsnew/
2.5.html):

"""
Another even more esoteric effect of this change: previously, the
gi_frame attribute of a generator was always a frame object. It?s now
possible for gi_frame to be None once the generator has been
exhausted.
"""

Cheers,
mk


From sjmachin at lexicon.net  Mon Jul 27 09:57:26 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 27 Jul 2009 06:57:26 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
References: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>
	<635a7311-62e1-4da5-98ad-b62cfa150287@k30g2000yqf.googlegroups.com> 
	<43b1acda-b518-40ef-acde-145e28379775@r25g2000vbn.googlegroups.com>
Message-ID: <281196a8-c392-4818-b2fb-6b60c84aba2a@j21g2000vbn.googlegroups.com>

On Jul 27, 8:49?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
> On Jul 27, 2:25?pm, John Machin <sjmac... at lexicon.net> wrote:
>
>
>
> > On Jul 27, 5:11?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
>
> > > Hi,
> > > ? ? I am facing a problem using PyArg_ParseTuple() in my C-API
> > > extension. Here is a small repro of the function:
>
> > > static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> > > {
> > > ? ? ? ? SQLUSMALLINT param_no = 0;
>
> > Sorry, my crystal ball is on the fritz. What is SQLUSMALLINT on
> > Windows/Linux/AIX?
> > What does
> > ? ? printf("%d %d %d\n", sizeof(SQLUSMALLINT), sizeof(int), sizeof
> > (long));
> > give you on each platform?

And the answer was: what?

> ? ? Thanks for the response. If I don't use SQLUSMALLINT and use int
> instead, then also I see the same problem.
> static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> ?{
> ? ? ? ? int param_no = 0;
> ....
> ....}
>
> This also prints out 0 for AIX and actual value passed in other
> platforms. If I initialize param_no with some other value (e.g. 90),
> it prints out that value.

Please run the following on AIX with Python 2.5:
   import sys
   print sys.byteorder, sys.maxint
   print sys.version
and tell us the output.

Does the C compiler that you are using for the extension correspond
with whatever is mentioned in sys.version about the C compiler used to
compile Python 2.5?

C code: Please add/change as follows:
   int dummy1 = 0xaaaabbbb;
   int param_no = 0xccccdddd;
   int dummy2 = 0xeeeeffff;
...
   printf("%08x %08x %08x\n", dummy1, param_no, dummy2);
   printf("%d %d\n", sizeof(int), sizeof(long));

Try this on AIX (a) with no optimisation (b) whatever O level you have
been using.

Try it with (i) small positive input (i) integer > 65535

Take a copy of your extension and cut out everything that is not part
of executing this function i.e. apart from this function (with the
dummies and printfs) you should have only a few includes, a table
defining just 1 callable function, and the minimal module
initialisation code. Check that this cut down version works on Windows
and Linux and still fails on AIX. Then try it without the first ("O")
arg. If it still fails on AIX, lose the first arg. Publish the minimal
failing code, the instructions to build the .so, and a transcript of
the Python interactive session showing calling the function and the
results.

Cheers,
John


From mdekauwe at gmail.com  Mon Jul 27 10:01:18 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 07:01:18 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
	<h4k9e6$tf9$02$1@news.t-online.com>
Message-ID: <8b78b47f-799e-4d37-bc28-d1ed349362c9@k6g2000yqn.googlegroups.com>

On Jul 27, 2:17 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > On Jul 27, 1:46 pm, Peter Otten <__pete... at web.de> wrote:
> >> Martin wrote:
> >> > On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
> >> >> Martin wrote:
> >> >> > I am new to python and I was wondering if there was a way to speed
> >> >> > up the way I index 2D arrays when I need to check two arrays
> >> >> > simultaneously? My current implementations is (using numpy)
> >> >> > something like the following...
>
> >> >> > for i in range(numrows):
> >> >> >     for j in range(numcols):
>
> >> >> >         if array_1[i, j] == some_value or array_2[i, j] >=
> >> >> >         array_1[i,
> >> >> > j] * some_other_value
> >> >> >             array_1[i, j] = some_new_value
>
> >> >> array_1[(array_1 == some_value) | (array_2 >= array_1 *
> >> >> some_other_value)] = some_new_value
>
> >> >> maybe?
>
> >> > So I tried...
>
> >> > band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
>
> >> > which led to
>
> >> > ValueError: The truth value of an array with more than one element is
> >> > ambiguous. Use a.any() or a.all()
>
> >> > so not sure that works?
>
> >> Copy and paste -- or replace "or" with "|".
>
> > apologies - I mistook that for a type for "or"
>
> > I now get the following error...
>
> > ValueError: shape mismatch: objects cannot be broadcast to a single
> > shape
>
> It seems array_1 and array_2 have a -- dada! -- different shape.
> Assuming array_1 is the smaller one:
>
> numrows, numcols = array_1.shape
> array_1[(array_1 == some_value) | (array_2[:numrows,:numcols] >= array_1 *
> some_other_value)] = some_new_value
>
> There may be other options, but I'm not a numpy expert.
>
> Peter

My mistake - the incorrect size in the arrays was my error.

The statement works now, but it doesn't give the same results as my
original logic, strangely!?

in my logic:

data = np.zeros((numrows, numcols), dtype = np.uint8, order ='C')

for i in range(numrows):
    for j in range(numcols):
        if band3[i,j] == 255 or band3[i,j] >= band6[i,j] * factor:
            data[i,j] = 0
        else:
            data[i,j] = 1

to do the same with what you suggested...

data = np.ones((numrows, numcols), dtype = np.uint8, order ='C')
data[(band3 == 255) | (band6 >= band3 * factor)] = 0

Thanks


From santhosh.vkumar at gmail.com  Mon Jul 27 10:04:48 2009
From: santhosh.vkumar at gmail.com (santhoshvkumar)
Date: Mon, 27 Jul 2009 07:04:48 -0700 (PDT)
Subject: iText for Python
Message-ID: <505f2bc1-cbfb-49a1-a7ef-0b6c357750a7@q35g2000vbi.googlegroups.com>

Hi all,
           One of my cousin  suggested me to do a IText PDF converter
for python. Actually I heard that there is no separate IText converter
either we have to go for jython or GCJ with wrapper. Instead of
wrapping, my plan is to create a separate module with Python and I am
thinking of doing this in as my final year project also. Kindly give
me your suggestion.

        With anticipation,

SanthoshVKumar.


From jeanmichel at sequans.com  Mon Jul 27 10:05:11 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 27 Jul 2009 16:05:11 +0200
Subject: Override a method but inherit the docstring
In-Reply-To: <87r5wggm0y.fsf@benfinney.id.au>
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <4A6DB417.5080601@sequans.com>

Ben Finney wrote:
> Howdy all,
>
> The following is a common idiom::
>
>     class FooGonk(object):
>         def frobnicate(self):
>             """ Frobnicate this gonk. """
>             basic_implementation(self.wobble)
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
>
> Ideally there would be a way to specify that the docstring should be
> inherited. The best I can come up with is::
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>         frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>
> but that violates DRY (the association between BarGonk and FooGonk is
> being repeated), puts the docstring assignment awkwardly after the end
> of the method instead of at the beginning where docstrings normally go,
> and reads poorly besides.
>
> What is the most Pythonic, DRY-adherent, and preferably least-ugly
> approach to override a method, but have the same docstring on both
> methods?
>
>   
I am using epydoc and if the docstring is present only in the baseclass 
method, it will repeat the docstring for the child methods. So 
basically, there's nothing to do.
I've also tried within the python interpreter, and it can perfectly 
solve docstring inheritance. So why would you explicitly assign 
docstring to child methods ?

JM


From invalid at invalid  Mon Jul 27 10:11:21 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 27 Jul 2009 09:11:21 -0500
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
Message-ID: <PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>

On 2009-07-27, r2 <rlichlighter at gmail.com> wrote:

> I have a memory dump from a machine I am trying to analyze. I can view
> the file in a hex editor to see text strings in the binary code. I
> don't see a way to save these ascii representations of the binary,

$ strings memdump.binary >memdump.strings

$ hexdump -C memdump.binary >memdump.hex+ascii

-- 
Grant Edwards                   grante             Yow! I'm ZIPPY the PINHEAD
                                  at               and I'm totally committed
                               visi.com            to the festive mode.


From jeanmichel at sequans.com  Mon Jul 27 10:17:13 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 27 Jul 2009 16:17:13 +0200
Subject: How to comment constant values?
In-Reply-To: <027cd65b$0$5185$c3e8da3@news.astraweb.com>
References: <200907270749.58845.devent@deventm.org>	<mailman.3750.1248645992.8015.python-list@python.org>	<7d44ndF29p3p7U2@mid.uni-berlin.de>
	<027cd65b$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A6DB6E9.3020308@sequans.com>

Steven D'Aprano wrote:
> On Mon, 27 Jul 2009 00:47:08 +0200, Diez B. Roggisch wrote:
>
>   
>>> Only modules, classes, and functions/methods can have docstrings
>>> associated with them.
>>> For anything else, you have to use comments; or you can mention them in
>>> the docstrings of related things.
>>>       
>> While this is technically true, writing docstrings to constants (module
>> or classlevel) works when one uses tools such as epydoc to generate
>> documentation.
>>     
>
> I've never used epydoc, so I'm not sure what you mean. Presumably it uses 
> source code analysis to detect:
>
> CONSTANT = 42
> """This is a constant."""
>
> even though the string is ignored by the compiler.
>
> Is that correct?
>
>
>   
Yes, and because it is perfectly ignored by the compiler there's no harm 
using this feature. I would add that even if you're not using epydoc, 
having a way top discriminate comments from documentation is 
recommended, their purpose are definitely not the same.

JM


From piet at cs.uu.nl  Mon Jul 27 10:23:04 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 16:23:04 +0200
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
	<b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>
	<m2ocrbk1k2.fsf@cs.uu.nl>
	<e004759b-4fd5-49b4-b3a6-1e2063a9aed9@v36g2000yqv.googlegroups.com>
Message-ID: <m23a8ib3xz.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> import M2Crypto
>j> from M2Crypto import RSA,SSL
>j> def encrypt():
>j>     pk = open('my_key.public.pem', 'rb').read()
>j>     rsa = M2Crypto.RSA.load_pub_key(pk) #return a M2Crypto.RSA.RSA_pub
>j> object.
>j>     plaintext = 4545479545655576767767686688782344
>j>     msg = rsa.public_encrypt(plaintext,RSA.pkcs1_padding)
>j>     print msg;
>j>     encrypt()

>j> This is code i am refering.
>j> The Problem is coming with .pem file.

You never tell what the problem is. Which error message do you get? Why
can't you just copy the error messages in your post instead of letting
us guess what is happening?

There are indeed problems with the code above. One warning: If you are
going to write cryptographic code while you really don't understand the
subject enough there is a big chance that your programs will have
security problems.

One more question: Do you have now a valid my_key.public.pem file? And
is it in the same directory where you run this program?

Here are the problems in your code (and there may be more!)

  import M2Crypto
  from M2Crypto import RSA,SSL

You never use the imports from the line above so you can leave it out.
SSL isn't used at all, and RSA is used as M2Crypto.RSA so it uses the
first import. Cleanliness is next to godliness.

  def encrypt():
      pk = open('my_key.public.pem', 'rb').read()
      rsa = M2Crypto.RSA.load_pub_key(pk) #return a M2Crypto.RSA.RSA_pub object.

load_pub_key requires a file name, not the contents of the file.
So use rsa = M2Crypto.RSA.load_pub_key('my_key.public.pem') and leave
the open line out.

      plaintext = 4545479545655576767767686688782344

That's not text, it is a number. rsa.public_encrypt will not accept a
number. So you would have to use 
      plaintext = "4545479545655576767767686688782344"
or convert the number to a byte array.

      msg = rsa.public_encrypt(plaintext,RSA.pkcs1_padding)
      print msg;
      encrypt()

The above line should be shifted to the left. It is not part of the
function otherwise you get an endless recursion.
And to answer another question from stackoverflow.com: RSA.pkcs1_padding
is a good parameter, if the decryption side will also use it.

See also my posting on the subject `RSA cryptography between Python and Java'.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From skip at pobox.com  Mon Jul 27 10:26:42 2009
From: skip at pobox.com (skip at pobox.com)
Date: Mon, 27 Jul 2009 09:26:42 -0500 (CDT)
Subject: Wrapping prstat on Solaris
Message-ID: <20090727142642.947081188353@montanaro.dyndns.org>

At work we currently use top to monitor ongoing system utilization on our
Solaris systems.  As time has moved on though, use of top has become
problematic.  Our admins want us to switch to prstat, Sun's top-like
command.  It works fine however doesn't emit a timestamp at each display
interval, so it's essentially impossible looking at a prstat output
file to determine when the particular "screen" was emitted.

If figured, "No problem.  I'll just write a little wrapper."  Alas, that is
proving harder than I thought.  I can run prstat directing output to a file
and it seems to blast out a block of lines every N seconds, but when run
from inside a Python script I can't seem to make the damn thing not
massively buffer its output.  Accordingly, my script doesn't really see the
output as its emitted, so the timestamp line it prepends to a block of
output is off.

I'm currently using subprocess.Popen like so:

    os.environ["TERM"] = "dumb"
    cmd = "prstat -c %s" % " ".join(sys.argv[1:])
    pipe = Popen(cmd, shell=True, bufsize=1, stdout=PIPE).stdout

I've tried these other variants as well:

  * prefacing the prstat command with unbuffer (the tcl/expect thingamabob)

  * explicitly redirect the prstat output to /dev/stdout

  * setting bufsize to 0

  * used os.popen instead of Subprocess.Popen

Nothing seems to help.  I always seem to see about 30 seconds of data at
once (I'm currently using a 5-second interval and 10 lines of output).  I
would have expected that prstat would simply flush stdout after each block
of output.

Any ideas about how to get prstat to cooperate better?

Thanks,

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    That's more than a dress. That's an Audrey Hepburn movie. -- Jerry Maguire


From simon at brunningonline.net  Mon Jul 27 10:31:11 2009
From: simon at brunningonline.net (Simon Brunning)
Date: Mon, 27 Jul 2009 15:31:11 +0100
Subject: iText for Python
In-Reply-To: <505f2bc1-cbfb-49a1-a7ef-0b6c357750a7@q35g2000vbi.googlegroups.com>
References: <505f2bc1-cbfb-49a1-a7ef-0b6c357750a7@q35g2000vbi.googlegroups.com>
Message-ID: <8c7f10c60907270731x1d416e64vde1907d8c4dd42d1@mail.gmail.com>

2009/7/27 santhoshvkumar <santhosh.vkumar at gmail.com>:
> ? ? ? ? ? One of my cousin ?suggested me to do a IText PDF converter
> for python. Actually I heard that there is no separate IText converter
> either we have to go for jython or GCJ with wrapper. Instead of
> wrapping, my plan is to create a separate module with Python and I am
> thinking of doing this in as my final year project also. Kindly give
> me your suggestion.

What would this give us that ReportLab does not? I wouldn't want to
see you spend a lot of time reinventing the wheel...

-- 
Cheers,
Simon B.


From aahz at pythoncraft.com  Mon Jul 27 10:32:53 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:32:53 -0700
Subject: Form/Template Fill-in the blanks
References: <4b77a992-370d-4879-88a0-fdd6a23f7c5d@p10g2000prm.googlegroups.com>
Message-ID: <h4kdql$b4a$1@panix3.panix.com>

In article <4b77a992-370d-4879-88a0-fdd6a23f7c5d at p10g2000prm.googlegroups.com>,
allan  <kawenks at gmail.com> wrote:
>
>My initial thought was to use:
>1. .ini files to declare the EDI configuration
>
>INI file configuration:
>* A "root" INI file indicates other INI files that define each segment
>of the EDI document.
>* Each segment INI defines the data elements of each segment and the
>behavior of the segment (one instance or multiple-instance as in a
>loop, sequence order, segment code, etc.)
>* Specify data elements as either constant, system function (like
>datetime), database field or object method (object being the
>segment's)
>* Load all the ini configuration into a "template" object. Each
>segment ini maps to its own segment object.

This sounds like something you want to use XML for.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From bryanvick at gmail.com  Mon Jul 27 10:37:53 2009
From: bryanvick at gmail.com (Bryan)
Date: Mon, 27 Jul 2009 07:37:53 -0700 (PDT)
Subject: Script runs manually, but cron fails
References: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
Message-ID: <ffa9d698-f620-4db1-aebc-eff7c930b983@e27g2000yqm.googlegroups.com>

On Jul 24, 2:11?pm, Bryan <bryanv... at gmail.com> wrote:
> I have a backup script that runs fine when I run it manually from the
> command line. ?When I run it with cron, the script stops running at
> random points in the source code.
>
> The script calls rsync with the subprocess module, which in turn uses
> ssh to backup files from a box on my lan. ?It also uses the atexit
> module to always run a certain piece of cleanup code when the script
> exits. ?However, this piece of code is never called when I use cron to
> run the script, but a ps -A command also does not show the python
> process so I know the script is dead. ?The log files generated by the
> script all show rsync as completing, but then the logging gets cutoff
> at random places when the script dies after that point. ?I am not
> getting any email from cron complaining of an error either.
>
> The script runs fine in my bash shell, what could cron be doing to
> interfere?

This script works when I run it at home, and I think it is because I
don't use rsync's ability to backup over ssh.  The working script at
home simply backs up the local machine to a mounted external hard
drive.  So when I run a python script that calls rsync to work over
ssh, cron is screwing things up.  Can anyone recommend where I should
report this behavior?  Should I email the author of cron directly, I
don't see a group/address specifically for cron bugs.


From kushal.kumaran+python at gmail.com  Mon Jul 27 10:40:40 2009
From: kushal.kumaran+python at gmail.com (Kushal Kumaran)
Date: Mon, 27 Jul 2009 20:10:40 +0530
Subject: Itext for Python
In-Reply-To: <b423b9550907270153v5b21cb35wc3741c8d5775e574@mail.gmail.com>
References: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com> 
	<b423b9550907270153v5b21cb35wc3741c8d5775e574@mail.gmail.com>
Message-ID: <1e364c4e0907270740sdc0e6ceye49f78b342820096@mail.gmail.com>

On Mon, Jul 27, 2009 at 2:23 PM, S.Selvam<s.selvamsiva at gmail.com> wrote:
>
>
> On Sun, Jul 26, 2009 at 11:52 PM, Santhosh Kumar <santhosh.vkumar at gmail.com>
> wrote:
>>
>> Hi all,
>> ?? ? ? ? ??One of my cousin ?suggested me to do a IText PDF?converter?for
>> python. Actually I heard that there is no?separate?IText?converter?either we
>> have to go for jython or GCJ with wrapper. Instead of wrapping, my plan is
>> to?create a separate module with Python and I am thinking of doing this in
>> as my final year project also. Kindly give me your?suggestion.
>
> As for as i know, no pure python module exists for iText PDF generator,
> where iText seems to be a standard one for PDF related works.There are some
> other modules for pdf work but might not be as standard as iText.Surely some
> senior programmers? will suggest you better way to proceed further.
>

AFAIK, iText is just a java library for generating PDF files.  You
could have a look at http://www.reportlab.org/rl_toolkit.html

-- 
kushal


From james at agentultra.com  Mon Jul 27 10:40:53 2009
From: james at agentultra.com (J Kenneth King)
Date: Mon, 27 Jul 2009 10:40:53 -0400
Subject: Script runs manually, but cron fails
References: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
Message-ID: <858wia6vey.fsf@agentultra.com>

Bryan <bryanvick at gmail.com> writes:

> I have a backup script that runs fine when I run it manually from the
> command line.  When I run it with cron, the script stops running at
> random points in the source code.
>
> The script calls rsync with the subprocess module, which in turn uses
> ssh to backup files from a box on my lan.  It also uses the atexit
> module to always run a certain piece of cleanup code when the script
> exits.  However, this piece of code is never called when I use cron to
> run the script, but a ps -A command also does not show the python
> process so I know the script is dead.  The log files generated by the
> script all show rsync as completing, but then the logging gets cutoff
> at random places when the script dies after that point.  I am not
> getting any email from cron complaining of an error either.
>
> The script runs fine in my bash shell, what could cron be doing to
> interfere?

Double check nothing is writing to stdout/stdin

Some cron's don't mind, but I always squelch output because some do.


From aahz at pythoncraft.com  Mon Jul 27 10:41:45 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:41:45 -0700
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>
	<h4iqgb$ss5$1@panix3.panix.com>
	<1c8ae01e-2e9c-497c-9f8d-408f56f9c0bd@g31g2000yqc.googlegroups.com>
Message-ID: <h4keb9$ita$1@panix3.panix.com>

In article <1c8ae01e-2e9c-497c-9f8d-408f56f9c0bd at g31g2000yqc.googlegroups.com>,
Michal Kwiatkowski  <constant.beta at gmail.com> wrote:
>On Jul 27, 1:56 am, a... at pythoncraft.com (Aahz) wrote:
>>>> Upon a cursory look, after a generator 'gen' is exhausted (meaning
>>>> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
>>>> None.
>>>
>>>Only in Python 2.5 or higher though. I need to support Python 2.3 and
>>>2.4 as well, sorry for not making that clear in the original post.
>>
>> Are you sure?  It appears to work in Python 2.4; I don't have time to
>> check 2.3.
>
>No, it does not work in Python 2.4. gi_frame can be None only in
>Python 2.5 and higher.

You're right, I guess I must have made a boo-boo when I was switching
versions.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From aahz at pythoncraft.com  Mon Jul 27 10:45:50 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:45:50 -0700
Subject: pyc files not automatically compiled on import
References: <mailman.3739.1248625343.8015.python-list@python.org>
Message-ID: <h4keiu$au1$1@panix3.panix.com>

In article <mailman.3739.1248625343.8015.python-list at python.org>,
Baz Walter  <bazwal at ftml.net> wrote:
>
>i thought that python automatically compiled pyc files after a module is 
>successfully imported. what could prevent this happening?

Looks like you got your problem fixed, but for the record, not having
write permission on a directory also causes this.  It's even uglier when
the .pyc already exists but does not have write perms.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From aahz at pythoncraft.com  Mon Jul 27 10:49:25 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:49:25 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
Message-ID: <h4kepl$qhf$1@panix3.panix.com>

In article <mailman.3765.1248685391.8015.python-list at python.org>,
Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>
>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>
>I have searched, but I can find nothing about this mediocre language.
>
>Could you tell us more?

:-P

(For anyone who is confused by Hendrik's humor, he is saying that David
was referring to a programming language named "mediocre".  English
grammar is confusing!)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From ethan at stoneleaf.us  Mon Jul 27 11:00:12 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Mon, 27 Jul 2009 08:00:12 -0700
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <468250.83203.qm@web31106.mail.mud.yahoo.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
Message-ID: <4A6DC0FC.90704@stoneleaf.us>

[corrected top posting]

Mohammad Tayseer wrote:
>> *From:* Piet van Oostrum <piet at cs.uu.nl>
>> *To:* python-list at python.org
>> *Sent:* Monday, July 27, 2009 11:18:20 AM
>> *Subject:* Re: Looking for a dream language: sounds like Python to me.
>> 
>>  >>>>> Dotan Cohen <dotancohen at gmail.com <mailto:dotancohen at gmail.com>> 
>> (DC) wrote:
>> 
>>  >DC> Referring to this article:
>>>DC> 
>> http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/
>> 
>>  >DC> The author, who is specifically looking for math-related 
>> functions, writes:
>>  >DC> """
>>  >DC> The dream algorithm R&D tool would be similar to Matlab or Mathematica
>>  >DC> but could be compiled to fast, efficient binaries similar to ANSI C
>>  >DC> and would be available for all platforms. An integrated GUI builder
>>  >DC> similar to Visual Basic and integrated network support would be
>>  >DC> helpful.
>>  >DC> """
>> 
>>  >DC> It looks to me like he is looking for Python.
>> 
>> No fast, efficient binaries yet, and no integrated GUI builder.
>> -- 
>> Piet van Oostrum <piet at cs.uu.nl <mailto:piet at cs.uu.nl>>
>> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
>> Private email: piet at vanoostrum.org <mailto:piet at vanoostrum.org>
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
 > You can generate binaries using py2exe, and you can create UI using
 > Tkinter (which is very easy) or wxPython (which have GUI builders)
 >
 > Mohammad Tayseer
 > http://spellcoder.com/blogs/tayseer

Creating binaries is not the same as creating /fast, efficient/ 
binaries.  Py2Exe bundles it all together, but does not make it any faster.

~Ethan~


From __peter__ at web.de  Mon Jul 27 11:12:02 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 17:12:02 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
	<h4k9e6$tf9$02$1@news.t-online.com>
	<8b78b47f-799e-4d37-bc28-d1ed349362c9@k6g2000yqn.googlegroups.com>
Message-ID: <h4kg42$fit$01$1@news.t-online.com>

Martin wrote:

> The statement works now, but it doesn't give the same results as my
> original logic, strangely!?
> 
> in my logic:
> 
> data = np.zeros((numrows, numcols), dtype = np.uint8, order ='C')
> 
> for i in range(numrows):
>     for j in range(numcols):
>         if band3[i,j] == 255 or band3[i,j] >= band6[i,j] * factor:
>             data[i,j] = 0
>         else:
>             data[i,j] = 1
> 
> to do the same with what you suggested...
> 
> data = np.ones((numrows, numcols), dtype = np.uint8, order ='C')
> data[(band3 == 255) | (band6 >= band3 * factor)] = 0

Did you swap band3 and band6? If that's the case, it is an error you should 
be able to find yourself.

Please be a bit more careful.

Also, it is good practice to write a few test cases where you have 
precalculated the result. How would you otherwise know which version is 
correct? Writing a third one to break the tie?

Peter




From dotancohen at gmail.com  Mon Jul 27 11:12:09 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Mon, 27 Jul 2009 18:12:09 +0300
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <4A6DC0FC.90704@stoneleaf.us>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
Message-ID: <880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>

> Creating binaries is not the same as creating /fast, efficient/ binaries.
> ?Py2Exe bundles it all together, but does not make it any faster.
>

How inefficient is py2exe. I was under the impression that it's really
not that bad.

-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From dns4 at cornell.edu  Mon Jul 27 11:14:15 2009
From: dns4 at cornell.edu (David Smith)
Date: Mon, 27 Jul 2009 11:14:15 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4kepl$qhf$1@panix3.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
Message-ID: <h4kg88$6s6$1@ruby.cit.cornell.edu>

Aahz wrote:
> In article <mailman.3765.1248685391.8015.python-list at python.org>,
> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>> I have searched, but I can find nothing about this mediocre language.
>>
>> Could you tell us more?
> 
> :-P
> 
> (For anyone who is confused by Hendrik's humor, he is saying that David
> was referring to a programming language named "mediocre".  English
> grammar is confusing!)

LOL ... I'm an American and that wasn't all that clear :-)


From exarkun at divmod.com  Mon Jul 27 11:18:41 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Mon, 27 Jul 2009 11:18:41 -0400
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
Message-ID: <20090727151841.388.143506053.divmod.quotient.793@henry.divmod.com>

On Mon, 27 Jul 2009 18:12:09 +0300, Dotan Cohen <dotancohen at gmail.com> wrote:
>> Creating binaries is not the same as creating /fast, efficient/ binaries.
>> ?Py2Exe bundles it all together, but does not make it any faster.
>>
>
>How inefficient is py2exe. I was under the impression that it's really
>not that bad.
>

py2exe doesn't really change the performance characteristics of a Python
application at all - for better or for worse.

Jean-Paul


From gmweezel at gmail.com  Mon Jul 27 11:21:29 2009
From: gmweezel at gmail.com (Eric)
Date: Mon, 27 Jul 2009 08:21:29 -0700 (PDT)
Subject: CRLF Newlines and libc
Message-ID: <6bcb4820-11be-4053-8e3b-849b00aba55a@c2g2000yqi.googlegroups.com>

I am working on the subprocess.Popen module for Google Summer of Code.
Right now, I am having difficulty trying to work out how to deal with
my '\n' newlines being converted to '\r\n' newlines when reading from
a pipe on windows; see this blog post (http://subdev.blogspot.com/
2009/07/stdout.html) and this chain on Python-Dev (http://
mail.python.org/pipermail/python-dev/2009-July/090720.html).

Right now, unless there is way to disable the newline conversions, I
am thinking I will just have to document the caveat and call it a day.
Is there a better way to handle this?

Eric


From cournape at gmail.com  Mon Jul 27 11:22:16 2009
From: cournape at gmail.com (David Cournapeau)
Date: Tue, 28 Jul 2009 00:22:16 +0900
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
Message-ID: <5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>

On Tue, Jul 28, 2009 at 12:12 AM, Dotan Cohen<dotancohen at gmail.com> wrote:
>> Creating binaries is not the same as creating /fast, efficient/ binaries.
>> ?Py2Exe bundles it all together, but does not make it any faster.
>>
>
> How inefficient is py2exe.

It is neither efficient or inefficient: it is just a distribution
tool, to deploy python software in a form familiar to most windows
users. It does not make it any faster than running the software under
a python prompt.

As much as I like python for scientific programming, I would say
python is pretty far from the stated requirements in the posted blog
post. It is difficult to deploy software written with python (much
better than the alternatives, though), and it is slow if you can't
leverage numpy/scipy (where vectorization does not apply).

It remains to be seen whether it will be true in practice, but
something like F#, with its integration in VS 2010, seems much closer
IMHO. It is compiled, high level language, and backed by the biggest
software vendor in the world.

David


From invalid at invalid  Mon Jul 27 11:24:27 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 27 Jul 2009 10:24:27 -0500
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl> <468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<mailman.3780.1248707531.8015.python-list@python.org>
Message-ID: <KtadnYzrE7w2W_DXnZ2dnUVZ_jhi4p2d@posted.visi>

On 2009-07-27, Dotan Cohen <dotancohen at gmail.com> wrote:
>> Creating binaries is not the same as creating /fast, efficient/ binaries.
>> ??Py2Exe bundles it all together, but does not make it any faster.
>
> How inefficient is py2exe.

[Assuming that was a question.]

py2exe just bundles up the files needed to run the program.
The result runs pretty much the same as it did when it was
"unbundled".  By default, py2exe combines some stuff in a zip
file, so that might slow down startup by a tiny amount. If
you don't like that, you can tell py2exe not to "zip" things
up, and then the program runs pretty much identically as did
the unbundled version.

> I was under the impression that it's really not that bad.

py2exe doesn't really have any impact on the program's
perfromance.  It's still the same Python VM running the same
bytecode using the same library files.

-- 
Grant Edwards                   grante             Yow! I'm totally DESPONDENT
                                  at               over the LIBYAN situation
                               visi.com            and the price of CHICKEN
                                                   ...


From dotancohen at gmail.com  Mon Jul 27 11:28:47 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Mon, 27 Jul 2009 18:28:47 +0300
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
Message-ID: <880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>

> It is neither efficient or inefficient: it is just a distribution
> tool, to deploy python software in a form familiar to most windows
> users. It does not make it any faster than running the software under
> a python prompt.
>
> As much as I like python for scientific programming, I would say
> python is pretty far from the stated requirements in the posted blog
> post. It is difficult to deploy software written with python (much
> better than the alternatives, though), and it is slow if you can't
> leverage numpy/scipy (where vectorization does not apply).
>
> It remains to be seen whether it will be true in practice, but
> something like F#, with its integration in VS 2010, seems much closer
> IMHO. It is compiled, high level language, and backed by the biggest
> software vendor in the world.
>

The blog post is not looking to distribute his code, but he would like
it to be cross platform for his own reasons. VB is not cross platform.


-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From cournape at gmail.com  Mon Jul 27 11:39:14 2009
From: cournape at gmail.com (David Cournapeau)
Date: Tue, 28 Jul 2009 00:39:14 +0900
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>
Message-ID: <5b8d13220907270839p3f65e1f8k7c1bb022bc922d6e@mail.gmail.com>

On Tue, Jul 28, 2009 at 12:28 AM, Dotan Cohen<dotancohen at gmail.com> wrote:
>> It is neither efficient or inefficient: it is just a distribution
>> tool, to deploy python software in a form familiar to most windows
>> users. It does not make it any faster than running the software under
>> a python prompt.
>>
>> As much as I like python for scientific programming, I would say
>> python is pretty far from the stated requirements in the posted blog
>> post. It is difficult to deploy software written with python (much
>> better than the alternatives, though), and it is slow if you can't
>> leverage numpy/scipy (where vectorization does not apply).
>>
>> It remains to be seen whether it will be true in practice, but
>> something like F#, with its integration in VS 2010, seems much closer
>> IMHO. It is compiled, high level language, and backed by the biggest
>> software vendor in the world.
>>
>
> The blog post is not looking to distribute his code, but he would like
> it to be cross platform for his own reasons. VB is not cross platform.

I understand his "efficient binary as Ansi C" partially as a
deployment requirement, and independent of cross-platform issues. As a
scientist, being able to share my software with colleagues is a non
trivial matter. Python does not make this easy today.

F# has nothing to do with VB: F# is a ML-language inspired from OCAML,
and run on top of the CLR. It can thus leverage the huge .net
framework (lack of non numerical API is one of the biggest matlab
hindrance, and comparatively big advantage of python + numpy/scipy),
and benefits from the much more efficient implementation compared to
python (under the currently CPython implementation at least).

Some recent F# versions are compatible with mono, making it compatible
on most platforms that matter today for research (but of course, you
lose the IDE integration outside windows).

David


From jakecjacobson at gmail.com  Mon Jul 27 11:44:40 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Mon, 27 Jul 2009 08:44:40 -0700 (PDT)
Subject: exceptions.TypeError an integer is required
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
	<0279f85d$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <8d03a739-7e45-49e1-b93d-6a396beed877@a37g2000prf.googlegroups.com>

On Jul 24, 3:11?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Fri, 24 Jul 2009 11:24:58 -0700, jakecjacobson wrote:
> > I am trying to do a post to a REST API over HTTPS and requires the
> > script to pass a cert to the server. ?I am getting "exceptions.TypeError
> > an integer is required" error and can't find the reason. ?I commenting
> > out the lines of code, it is happening on the connection.request() line.
> > ?Here is the problem code. ?Would love some help if possible.
>
> Please post the traceback that you get.
>
> My guess is that you are passing a string instead of an integer, probably
> for the port.
>
> [...]
>
> > ? ?except:
> > ? ? ? ? ? ?print sys.exc_type, sys.exc_value
>
> As a general rule, a bare except of that fashion is bad practice. Unless
> you can explain why it is normally bad practice, *and* why your case is
> an exception (no pun intended) to the rule "never use bare except
> clauses", I suggest you either:
>
> * replace "except:" with "except Exception:" instead.
>
> * better still, re-write the entire try block as:
>
> ? ? try:
> ? ? ? ? [code goes here]
> ? ? finally:
> ? ? ? ? connection.close()
>
> and use the Python error-reporting mechanism instead of defeating it.
>
> --
> Steven

Steven,

You are quite correct in your statements.  My goal was not to make
great code but something that I could quickly test.  My assumption was
that the httplib.HTTPSConnection() would do the cast to int for me.
As soon as I cast it to an int, I was able to get past that issue.

Still not able to post because I am getting a bad cert error.

Jake Jacobson


From jakecjacobson at gmail.com  Mon Jul 27 11:57:40 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Mon, 27 Jul 2009 08:57:40 -0700 (PDT)
Subject: bad certificate error
Message-ID: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>

Hi,

I am getting the following error when doing a post to REST API,

Enter PEM pass phrase:
Traceback (most recent call last):
  File "./ices_catalog_feeder.py", line 193, in ?
    main(sys.argv[1])
  File "./ices_catalog_feeder.py", line 60, in main
    post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
(input_dir, file), collection_name, key_file, cert_file)
  File "./ices_catalog_feeder.py", line 125, in post2Catalog
    connection.request('POST', path, parameters, head)
  File "/usr/lib/python2.4/httplib.py", line 810, in request
    self._send_request(method, url, body, headers)
  File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
    self.endheaders()
  File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
    self._send_output()
  File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
    self.send(msg)
  File "/usr/lib/python2.4/httplib.py", line 652, in send
    self.connect()
  File "/usr/lib/python2.4/httplib.py", line 1079, in connect
    ssl = socket.ssl(sock, self.key_file, self.cert_file)
  File "/usr/lib/python2.4/socket.py", line 74, in ssl
    return _realssl(sock, keyfile, certfile)
socket.sslerror: (1, 'error:14094412:SSL
routines:SSL3_READ_BYTES:sslv3 alert bad certificate')


My code where this error occurs is:

head = {"Content-Type" : "application/x-www-form-urlencoded",
"Accept" : "text/plain"}
parameters = urlencode({"collection" : collection, "entryxml" : open
(file,'r').read()})
print "Sending the file to: " + host

try:
	try:
		# Default port is 443.
		# key_file is the name of a PEM formatted file that contains your
private key.
		# cert_file is a PEM formatted certificate chain file.
		connection = httplib.HTTPSConnection(host, int(port), key_file,
cert_file)
		connection.request('POST', path, parameters, head)
		response = connection.getresponse()
		print response.status, response.reason
	except httplib.error, (value,message):
		print value + ':' + message
finally:
	connection.close()

I was wondering if this is due to the server having a invalid server
cert?  If I go to this server in my browser, I get a "This server
tried to identify itself with invalid information".  Is there a way to
ignore this issue with Python?  Can I setup a trust store and add this
server to the trust store?


From mdekauwe at gmail.com  Mon Jul 27 12:00:41 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 09:00:41 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
	<h4k9e6$tf9$02$1@news.t-online.com>
	<8b78b47f-799e-4d37-bc28-d1ed349362c9@k6g2000yqn.googlegroups.com>
	<h4kg42$fit$01$1@news.t-online.com>
Message-ID: <f0ead2ff-c7a3-4271-8311-049db3d203e9@c29g2000yqd.googlegroups.com>

On Jul 27, 4:12 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > The statement works now, but it doesn't give the same results as my
> > original logic, strangely!?
>
> > in my logic:
>
> > data = np.zeros((numrows, numcols), dtype = np.uint8, order ='C')
>
> > for i in range(numrows):
> >     for j in range(numcols):
> >         if band3[i,j] == 255 or band3[i,j] >= band6[i,j] * factor:
> >             data[i,j] = 0
> >         else:
> >             data[i,j] = 1
>
> > to do the same with what you suggested...
>
> > data = np.ones((numrows, numcols), dtype = np.uint8, order ='C')
> > data[(band3 == 255) | (band6 >= band3 * factor)] = 0
>
> Did you swap band3 and band6? If that's the case, it is an error you should
> be able to find yourself.
>
> Please be a bit more careful.
>
> Also, it is good practice to write a few test cases where you have
> precalculated the result. How would you otherwise know which version is
> correct? Writing a third one to break the tie?
>
> Peter

apologies... it was the way I typed it up, I wasn't copying and
pasting from my text editor!
Thanks Peter.


From davea at ieee.org  Mon Jul 27 12:09:38 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 12:09:38 -0400
Subject: [python-win32] subprocess and stdout
In-Reply-To: <BAY112-W553A4383329E89926BF75F7140@phx.gbl>
References: <BAY112-DS5EA522027B7C10D4AC9C8F7170@phx.gbl>
	<4A6D9D83.6050505@ieee.org>
	<BAY112-W553A4383329E89926BF75F7140@phx.gbl>
Message-ID: <4A6DD142.7040809@ieee.org>

(This message was top-posted, and sent off-list.  So I'm copying it back 
to the list, with my response at the end)

Chris Chapman wrote:
> Thanks Dave.  You know after trying your suggestion on the command prompt it doesn't as a matter of fact.  Not sure why I didn't just try that in windows to begin with.  Guess I got stuck more on the python issue then it being the other program.
>
> There is an option for it to create an HTML log file, but it's formatted sort of strangely.  I'm really not looking to parse through it just for a summary like that presented on the terminal.  I'm not sure if you know but I'm guessing parsing the HTML would be a lot easier the trying to capture the console output from the buffer, huh?  Thanks again for the help.
>
> Chris
>
>   
>> Date: Mon, 27 Jul 2009 08:28:51 -0400
>> From: davea at ieee.org
>> To: oxydol010 at hotmail.com
>> CC: python-win32 at python.org
>> Subject: Re: [python-win32] subprocess and stdout
>>
>> Christopher Chapman wrote:
>>     
>>> I'm trying to write a "module" to a larger program.  This module eventually
>>> needs to reference a config file with setup information in it, but I'm not
>>> there yet.  I'm using the subprocess module to run an external antivirus
>>> program and trying to get the output written to a log file, but I keep
>>> getting a weird return.  My code is listed below.  I'm a noob to Python so
>>> I'm not sure if this is a windows specific issue or not, but I'm programming
>>> on windows and more then likely what I'm working on won't be on anything
>>> other then a windows machine.  I'm also writing my code for 3.1 if that
>>> makes any difference.
>>>
>>> # Pass target path to scanners command line and write output to a file
>>> # Currently "scan" only targets the McAfee Command Line Scanner
>>> print() 
>>> print ("Begining scan of " + target)
>>> print()
>>> scan = "scan /all " + target
>>> s = subprocess.Popen(scan,
>>>                      stdout=subprocess.PIPE)
>>> out = s.communicate()[0]
>>> chgout = str(out)
>>> s.wait()
>>> scanlog.write(chgout)
>>> scanlog.close
>>> "
>>> If I change my stdout in s subprocess to None then everything gets written
>>> to the terminal as if I had just run the program straight from the command
>>> line, but when I try piping it to my file "scanlog" then literally the only
>>> return I get in the file is '' or two single quotes.  I've even tried piping
>>> the output and then printing it instead of writing it to a file and I get
>>> the same result.  I've experimented with standard windows command line
>>> commands and using the same syntax was able to pipe directory listings and
>>> other things to my file.  Any ideas what I'm missing here?  Thanks in
>>> advance
>>>
>>> Chris Chapman
>>>
>>>
>>>   
>>>       
>> I suspect it's because of the way the antivirus program is written.  I 
>> can't be sure what you tried at the command prompt, but have you tried this:
>>
>> c:\>scan /all > scanlog.txt
>>
>>
>> If this does not capture to the file, then scan.exe isn't written in the 
>> way you're expecting.  There are several ways to write directly to a 
>> console that do not redirect or pipe.
>>
>> You might also look to see whether scan has any other commandline 
>> options.  One of them might be to create a log file.
>>
>> DaveA
>>     
>
>   

I wouldn't know where to begin trying to capture output that another 
process sends to its console window.  While I'm sure it's possible, I do 
suspect that parsing the html would be easier.  Remember that even if it 
looks ugly, it is generated by program, and it's quite possible that you 
could throw away the fluff and end up with a simple summary.  There are 
libraries to make this easier, but I've never used them.  If it's valid 
xhtml, which is by definition valid xml, you might find it useful to use 
elementree.  But most html is buggy, and parsing that takes a more 
tolerant parser.

DaveA



From robert.kern at gmail.com  Mon Jul 27 12:11:02 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Mon, 27 Jul 2009 11:11:02 -0500
Subject: quickly looping over a 2D array?
In-Reply-To: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
Message-ID: <h4kjim$mgj$1@ger.gmane.org>

On 2009-07-27 06:24, Martin wrote:
> Hi,
>
> I am new to python and I was wondering if there was a way to speed up
> the way I index 2D arrays when I need to check two arrays
> simultaneously? My current implementations is (using numpy) something
> like the following...
>
> for i in range(numrows):
>      for j in range(numcols):
>
>          if array_1[i, j] == some_value or array_2[i, j]>= array_1[i,
> j] * some_other_value
>              array_1[i, j] = some_new_value

Peter has given you good answers, but you will probably want to ask future numpy 
questions on the numpy mailing list.

   http://www.scipy.org/Mailing_Lists

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python at mrabarnett.plus.com  Mon Jul 27 12:34:03 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 27 Jul 2009 17:34:03 +0100
Subject: New implementation of re module
Message-ID: <4A6DD6FB.8040609@mrabarnett.plus.com>

Hi all,

I've been working on a new implementation of the re module. The details
are at http://bugs.python.org/issue2636, specifically from
http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
Python 2.6 on Windows if you want to try it out.

I'm interested in how fast it is generally, compared with the current re
module, but especially when faced with those 'pathological' regular
expressions which seem to take a long time to finish, for example:

     re.search(r"^(.+|D)*A$", "x" * 25 + "B")

which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs 
with this new implementation.

TIA


From Ray.Joseph at CDICorp.com  Mon Jul 27 12:42:06 2009
From: Ray.Joseph at CDICorp.com (ray)
Date: Mon, 27 Jul 2009 09:42:06 -0700 (PDT)
Subject: Using easy_install, reduncant?
Message-ID: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>

I am working on a Trac installation.  I am new to Python.  To install
packages, it is suggested to use setuptools.  I have not understood
the directions.

I execute ez_install.py.

Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
There response that setuptools is already the active version in easy-
install.pth.  Then:
Installing easy_install.exe script to C:\Python26\Scripts error:  C:
\Python26\Scripts\Easy_install.exe: Permission denied.

I have compared the file entries before and after this attempt and
there are no new files.  Is there any problems here?  What did I miss?

Regards,
Ray


From nagle at animats.com  Mon Jul 27 12:58:57 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 09:58:57 -0700
Subject: Using easy_install, reduncant?
In-Reply-To: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
References: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
Message-ID: <4a6ddc22$0$1667$742ec2ed@news.sonic.net>

ray wrote:
> I am working on a Trac installation.  I am new to Python.  To install
> packages, it is suggested to use setuptools.  I have not understood
> the directions.
> 
> I execute ez_install.py.
> 
> Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
> There response that setuptools is already the active version in easy-
> install.pth.  Then:
> Installing easy_install.exe script to C:\Python26\Scripts error:  C:
> \Python26\Scripts\Easy_install.exe: Permission denied.

    "Easy Install" usually isn't "easy".  If it works, it's great.
Most of the time, it doesn't.  It's not very good at finding all the
files it needs to update.  Hence problems like the above.

				John Nagle


From deets at nospam.web.de  Mon Jul 27 13:00:52 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 19:00:52 +0200
Subject: Using easy_install, reduncant?
References: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
	<4a6ddc22$0$1667$742ec2ed@news.sonic.net>
Message-ID: <7d64q4F2an2drU1@mid.uni-berlin.de>

John Nagle wrote:

> ray wrote:
>> I am working on a Trac installation.  I am new to Python.  To install
>> packages, it is suggested to use setuptools.  I have not understood
>> the directions.
>> 
>> I execute ez_install.py.
>> 
>> Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
>> There response that setuptools is already the active version in easy-
>> install.pth.  Then:
>> Installing easy_install.exe script to C:\Python26\Scripts error:  C:
>> \Python26\Scripts\Easy_install.exe: Permission denied.
> 
>     "Easy Install" usually isn't "easy".  If it works, it's great.
> Most of the time, it doesn't.  It's not very good at finding all the
> files it needs to update.  Hence problems like the above.

Which is the usual BS from you. It works most of the times as advertised,
and in the concrete case the OP misunderstood what ez_setup.py does
(already installing setuptools), and thus the complaint about "already
active version". Which btw is just a warning, and setuptools would
continue, but as the OP works on Windows which prohibits a running
executable to be replaced, it fails. Again, not setuptools fault.

Diez


From nagle at animats.com  Mon Jul 27 13:23:43 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 10:23:43 -0700
Subject: M2Crypto hangs on this URL
Message-ID: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>

There's something strange about this URL:

"https://sagar310.pontins.com/sraep/"

It hangs Firefox 2; there's no short timeout, the web page just gets
stuck in initial load for about ten minutes.  Then
"The connection to sagar310.pontins.com was interrupted while the page was loading."

It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.

What does the new SSL implementation do?  (Haven't tried that yet;
waiting for MySQL support for Python 3.x before converting web apps.)

				John Nagle


From rlichlighter at gmail.com  Mon Jul 27 13:25:18 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 10:25:18 -0700 (PDT)
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<h4k8o8$ght$00$1@news.t-online.com>
Message-ID: <bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>

On Jul 27, 9:06?am, Peter Otten <__pete... at web.de> wrote:
> r2 wrote:
> > I have a memory dump from a machine I am trying to analyze. I can view
> > the file in a hex editor to see text strings in the binary code. I
> > don't see a way to save these ascii representations of the binary, so
> > I went digging into Python to see if there were any modules to help.
>
> > I found one I think might do what I want it to do - the binascii
> > module. Can anyone describe to me how to convert a raw binary file to
> > an ascii file using this module. I've tried? Boy, I've tried.
>
> That won't work because a text editor doesn't need any help to convert the
> bytes into characters. If it expects ascii it just will be puzzled by bytes
> that are not valid ascii. Also, it will happily display byte sequences that
> are valid ascii, but that you as a user will see as gibberish because they
> were meant to be binary data by the program that wrote them.
>
> > Am I correct in assuming I can get the converted binary to ascii text
> > I see in a hex editor using this module? I'm new to this forensics
> > thing and it's quite possible I am mixing technical terms. I am not
> > new to Python, however. Thanks for your help.
>
> Unix has the "strings" commandline tool to extract text from a binary.
> Get hold of a copy of the MinGW tools if you are on windows.
>
> Peter

Okay. Thanks for the guidance. I have a machine with Linux, so I
should be able to do what you describe above. Could Python extract the
strings from the binary as well? Just wondering.


From rlichlighter at gmail.com  Mon Jul 27 13:25:44 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 10:25:44 -0700 (PDT)
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>
Message-ID: <fb63e796-f92f-4436-b6bd-da91ca7989ce@n11g2000yqb.googlegroups.com>

On Jul 27, 10:11?am, Grant Edwards <invalid at invalid> wrote:
> On 2009-07-27, r2 <rlichligh... at gmail.com> wrote:
>
> > I have a memory dump from a machine I am trying to analyze. I can view
> > the file in a hex editor to see text strings in the binary code. I
> > don't see a way to save these ascii representations of the binary,
>
> $ strings memdump.binary >memdump.strings
>
> $ hexdump -C memdump.binary >memdump.hex+ascii
>
> --
> Grant Edwards ? ? ? ? ? ? ? ? ? grante ? ? ? ? ? ? Yow! I'm ZIPPY the PINHEAD
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? at ? ? ? ? ? ? ? and I'm totally committed
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?visi.com ? ? ? ? ? ?to the festive mode.

Grant,

Thanks for the commands!


From reckoner at gmail.com  Mon Jul 27 13:40:03 2009
From: reckoner at gmail.com (Reckoner)
Date: Mon, 27 Jul 2009 10:40:03 -0700 (PDT)
Subject: initializing with empty list as default causes freaky problems
Message-ID: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>

Hi,

Observe the following:

In [202]: class Foo():
   .....:     def __init__(self,h=[]):
   .....:         self.h=h
   .....:
   .....:

In [203]: f=Foo()

In [204]: g=Foo()

In [205]: g.h
Out[205]: []

In [206]: f.h
Out[206]: []

In [207]: f.h.append(10)

In [208]: f.h
Out[208]: [10]

In [209]: g.h
Out[209]: [10]

The question is: why is g.h updated when I append to f.h?  Shouldn't
g.h stay []?

What am I missing here?

I'm using Python 2.5.1.

Thanks in advance.


From python at mrabarnett.plus.com  Mon Jul 27 13:55:57 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 27 Jul 2009 18:55:57 +0100
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <4A6DEA2D.6000408@mrabarnett.plus.com>

Reckoner wrote:
> Hi,
> X-Antispam: NO; Spamcatcher 5.2.1. Score 50
> 
> Observe the following:
> 
> In [202]: class Foo():
>    .....:     def __init__(self,h=[]):
>    .....:         self.h=h
>    .....:
>    .....:
> 
> In [203]: f=Foo()
> 
> In [204]: g=Foo()
> 
> In [205]: g.h
> Out[205]: []
> 
> In [206]: f.h
> Out[206]: []
> 
> In [207]: f.h.append(10)
> 
> In [208]: f.h
> Out[208]: [10]
> 
> In [209]: g.h
> Out[209]: [10]
> 
> The question is: why is g.h updated when I append to f.h?  Shouldn't
> g.h stay []?
> 
> What am I missing here?
> 
> I'm using Python 2.5.1.
> 
Default arguments are evaluated once and then shared, so don't use them
with mutable objects like lists. Do this instead:

     class Foo():
         def __init__(self, h=None):
             if h is None:
                 self.h = []
             else:
                 self.h = h


From __peter__ at web.de  Mon Jul 27 14:07:37 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 20:07:37 +0200
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<h4k8o8$ght$00$1@news.t-online.com>
	<bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
Message-ID: <h4kqd9$5h2$01$1@news.t-online.com>

r2 wrote:

> On Jul 27, 9:06 am, Peter Otten <__pete... at web.de> wrote:
>> r2 wrote:
>> > I have a memory dump from a machine I am trying to analyze. I can view
>> > the file in a hex editor to see text strings in the binary code. I
>> > don't see a way to save these ascii representations of the binary, so
>> > I went digging into Python to see if there were any modules to help.
>>
>> > I found one I think might do what I want it to do - the binascii
>> > module. Can anyone describe to me how to convert a raw binary file to
>> > an ascii file using this module. I've tried? Boy, I've tried.
>>
>> That won't work because a text editor doesn't need any help to convert
>> the bytes into characters. If it expects ascii it just will be puzzled by
>> bytes that are not valid ascii. Also, it will happily display byte
>> sequences that are valid ascii, but that you as a user will see as
>> gibberish because they were meant to be binary data by the program that
>> wrote them.
>>
>> > Am I correct in assuming I can get the converted binary to ascii text
>> > I see in a hex editor using this module? I'm new to this forensics
>> > thing and it's quite possible I am mixing technical terms. I am not
>> > new to Python, however. Thanks for your help.
>>
>> Unix has the "strings" commandline tool to extract text from a binary.
>> Get hold of a copy of the MinGW tools if you are on windows.
>>
>> Peter
> 
> Okay. Thanks for the guidance. I have a machine with Linux, so I
> should be able to do what you describe above. Could Python extract the
> strings from the binary as well? Just wondering.

As a special service for you here is a naive implementation to build upon:

#!/usr/bin/env python
import sys

wanted_chars = ["\0"]*256
for i in range(32, 127):
    wanted_chars[i] = chr(i)
wanted_chars[ord("\t")] = "\t"
wanted_chars = "".join(wanted_chars)

THRESHOLD = 4

for s in sys.stdin.read().translate(wanted_chars).split("\0"):
    if len(s) >= THRESHOLD:
        print s

Peter



From nagle at animats.com  Mon Jul 27 14:13:40 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 11:13:40 -0700
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
Message-ID: <4a6deda5$0$1639$742ec2ed@news.sonic.net>

John Nagle wrote:
> There's something strange about this URL:
> 
> "https://sagar310.pontins.com/sraep/"
> 
> It hangs Firefox 2; there's no short timeout, the web page just gets
> stuck in initial load for about ten minutes.  Then
> "The connection to sagar310.pontins.com was interrupted while the page 
> was loading."
> 
> It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.

     Correction: Linux is still hung at 5 hours, but Windows timed out
after about 15 minutes.

				John Nagle


From gagsl-py2 at yahoo.com.ar  Mon Jul 27 14:14:38 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 15:14:38 -0300
Subject: CRLF Newlines and libc
References: <6bcb4820-11be-4053-8e3b-849b00aba55a@c2g2000yqi.googlegroups.com>
Message-ID: <op.uxqnmoa2x6zn5v@gabriel.sleipnir-bsas>

En Mon, 27 Jul 2009 12:21:29 -0300, Eric <gmweezel at gmail.com> escribi?:

> I am working on the subprocess.Popen module for Google Summer of Code.
> Right now, I am having difficulty trying to work out how to deal with
> my '\n' newlines being converted to '\r\n' newlines when reading from
> a pipe on windows; see this blog post (http://subdev.blogspot.com/
> 2009/07/stdout.html) and this chain on Python-Dev (http://
> mail.python.org/pipermail/python-dev/2009-July/090720.html).
>
> Right now, unless there is way to disable the newline conversions, I
> am thinking I will just have to document the caveat and call it a day.
> Is there a better way to handle this?

It isn't clear to me what exactly your problem is. What are you reading,  
using which functions, how did you open the file? On the writing side, how  
did you open the file, which functions are used to write?

The Windows API functions like CreateFile, ReadFile, WriteFile... don't  
perform any kind of '\n' conversion, neither reading nor writing. On the  
other hand, the C library does differentiate between files opened in text  
mode or binary mode (this comes from the ANSI C standard, it's not Windows  
specific). The default is "text" mode (unless you add "b" to the fopen  
call, or O_BINARY to the open call). In that mode, '\n' is translated to  
'\r\n' on writing, and '\r\n' is translated to '\n' on reading.
Python files are implemented on top of the C library (on 2.x) so they  
inherit that behaviour.
Console programs written in C and using printf/fwrite/write to stdout  
share that behaviour too (standard handles are opened in text mode by  
default).

Note that """'\n' newlines being converted to '\r\n' newlines when  
reading""" cannot happen -- if you see '\r\n' when reading, it's because
a) you're reading the file in binary mode, and
b) the file was written in text mode.

b) is true for process output redirected to a pipe, so you'll have to fix  
a). How to do that, depends on what exactly you're doing.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 14:23:41 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 15:23:41 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
Message-ID: <op.uxqn1rxcx6zn5v@gabriel.sleipnir-bsas>

En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson  
<jakecjacobson at gmail.com> escribi?:

> I was wondering if this is due to the server having a invalid server
> cert?  If I go to this server in my browser, I get a "This server
> tried to identify itself with invalid information".  Is there a way to
> ignore this issue with Python?  Can I setup a trust store and add this
> server to the trust store?

I don't see the point in trusting someone that you know is telling lies  
about itself.

-- 
Gabriel Genellina



From kyrie at uh.cu  Mon Jul 27 14:25:47 2009
From: kyrie at uh.cu (Luis Alberto Zarrabeitia Gomez)
Date: Mon, 27 Jul 2009 14:25:47 -0400
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <1248719147.4a6df12b61835@mail.uh.cu>



Quoting Reckoner <reckoner at gmail.com>:

> Hi,
> 
> Observe the following:
> 
> In [202]: class Foo():
>    .....:     def __init__(self,h=[]):
>    .....:         self.h=h
[...]
> In [207]: f.h.append(10)
> 
> In [208]: f.h
> Out[208]: [10]
> 
> In [209]: g.h
> Out[209]: [10]
> 
> The question is: why is g.h updated when I append to f.h?  Shouldn't
> g.h stay []?

What you are seeing is basically the same that happens here: 

===
In [1]: def f(l=[]):
   ...:     l.append(1)
   ...:     print l
   ...: 

In [2]: f()
[1]

In [3]: f()
[1, 1]

In [4]: f()
[1, 1, 1]
===

The problem is that the default value "[]" is evaluated only once, at function
creation time, and not at invocation. Thus, every call to the function shares
the same default object. That is consistent with python's function type: the
"def" construct just creates a function object and initializes it with the code,
argument list and default values. That means that the default value are part of
the function object itself, regardless of when/if it is called:

===
In [5]: f.func_defaults
Out[5]: ([1, 1, 1],)
===

The recommended way of dealing with this case (mutable default arguments) is:

def f(l = None):
    if l is None:
        l = []
    # the code goes here.

(in your case, your g.__init__ and f.__init__ methods share the same
Foo.__init__ function, and thus, share the same default value [])

That is a very common python gotcha, and I think it is well documented in the
standard doc (but I can't find it right now, sorry). Unfortunately, it doesn't
become intuitive until you've spent a while understanding python's execution
model (and then you suddenly realize that it just makes sense).

[And now I wonder... how other languages do it? I've spent so much time with
python that reevaluating the default argument on invocation feels clumsy, but
I'm obviously tainted now...]

Regards,

-- 
Luis Zarrabeitia
Facultad de Matem?tica y Computaci?n, UH
http://profesores.matcom.uh.cu/~kyrie



-- 
Participe en Universidad 2010, del 8 al 12 de febrero de 2010
La Habana, Cuba 
http://www.universidad2010.cu



From niedziala at gazeta.pl  Mon Jul 27 14:43:36 2009
From: niedziala at gazeta.pl (Piotrek)
Date: Mon, 27 Jul 2009 20:43:36 +0200
Subject: where do I put resources (images,
	audio files) when I wrote Python program?
Message-ID: <h4ksgo$qa9$1@inews.gazeta.pl>

Hello,

I write a Python program. It will contain some images (in .png format), some
audio files (as .ogg) etc. Now I think where should my installer put these
files and how should I access them. What is the normal Python way of doing
that? I think about puting these files in /usr/share/myprogram and then
reading it the normal way (so the path "/usr/share/myprogram" would be just
hardwired in my program). Is it the way one usually does it in Python
program or is there any more sofisticated way?



From jakecjacobson at gmail.com  Mon Jul 27 14:52:08 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Mon, 27 Jul 2009 11:52:08 -0700 (PDT)
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
Message-ID: <157f16f9-2172-4fd5-8ec8-8d9569a3f186@f20g2000prn.googlegroups.com>

On Jul 27, 2:23?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson ?
> <jakecjacob... at gmail.com> escribi?:
>
> > I was wondering if this is due to the server having a invalid server
> > cert? ?If I go to this server in my browser, I get a "This server
> > tried to identify itself with invalid information". ?Is there a way to
> > ignore this issue with Python? ?Can I setup a trust store and add this
> > server to the trust store?
>
> I don't see the point in trusting someone that you know is telling lies ?
> about itself.
>
> --
> Gabriel Genellina

It is a test box that the team I am on runs.  That is why I would
trust it.


From mhearne808 at gmail.com  Mon Jul 27 14:57:28 2009
From: mhearne808 at gmail.com (mhearne808)
Date: Mon, 27 Jul 2009 11:57:28 -0700 (PDT)
Subject: where do I put resources (images, audio files) when I wrote 
	Python program?
References: <h4ksgo$qa9$1@inews.gazeta.pl>
Message-ID: <f5db92ff-f54f-47ea-bab8-f86883aa2eb3@d32g2000yqh.googlegroups.com>

On Jul 27, 12:43?pm, Piotrek <niedzi... at gazeta.pl> wrote:
> Hello,
>
> I write a Python program. It will contain some images (in .png format), some
> audio files (as .ogg) etc. Now I think where should my installer put these
> files and how should I access them. What is the normal Python way of doing
> that? I think about puting these files in /usr/share/myprogram and then
> reading it the normal way (so the path "/usr/share/myprogram" would be just
> hardwired in my program). Is it the way one usually does it in Python
> program or is there any more sofisticated way?

Usually the preferred method is either distutils (http://
docs.python.org/library/distutils.html#module-distutils) or setuptools
(http://peak.telecommunity.com/DevCenter/setuptools).  Either of these
will allow you to create source (".tar.gz") or binary distributions
that can be installed relatively easily on a target machine.

Good luck,
Mike


From wilk at flibuste.net  Mon Jul 27 15:04:59 2009
From: wilk at flibuste.net (William Dode)
Date: 27 Jul 2009 19:04:59 GMT
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <4a6dfa5b$0$10245$426a74cc@news.free.fr>

On 27-07-2009, MRAB wrote:
> Hi all,
>
> I've been working on a new implementation of the re module. The details
> are at http://bugs.python.org/issue2636, specifically from
> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
> Python 2.6 on Windows if you want to try it out.
>

Someone can remember me how to compile it (on debian lenny), if possible 
with python2.5. I've also python3.1 that i build alone...

I could test it with pytextile, i've a bunch of texts to bench and 
compare.

Did you announce it on the unladen-swallow list ? They wanted to hack on 
RE also...


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From joshua at joshuakugler.com  Mon Jul 27 15:09:47 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Mon, 27 Jul 2009 11:09:47 -0800
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<24654358.post@talk.nabble.com>
Message-ID: <h4ku1s$u8h$1@ger.gmane.org>

Dr. Phillip M. Feldman wrote:

> 
> "As far as I know, there is no programming language which treats scalars
> like ints as if they were
> vectors of length 1"
> 
> Actually, Matlab does:
> 
>>> length(5)
> ans =
>      1
>>> 

Oddly enough, so does Perl:

$ print length(44)
2

(that's in the Zoidberg shell)

j




From deets at nospam.web.de  Mon Jul 27 15:26:46 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 21:26:46 +0200
Subject: Wrapping prstat on Solaris
In-Reply-To: <mailman.3776.1248704814.8015.python-list@python.org>
References: <mailman.3776.1248704814.8015.python-list@python.org>
Message-ID: <7d6dbmF2ahp61U1@mid.uni-berlin.de>

skip at pobox.com schrieb:
> At work we currently use top to monitor ongoing system utilization on our
> Solaris systems.  As time has moved on though, use of top has become
> problematic.  Our admins want us to switch to prstat, Sun's top-like
> command.  It works fine however doesn't emit a timestamp at each display
> interval, so it's essentially impossible looking at a prstat output
> file to determine when the particular "screen" was emitted.
> 
> If figured, "No problem.  I'll just write a little wrapper."  Alas, that is
> proving harder than I thought.  I can run prstat directing output to a file
> and it seems to blast out a block of lines every N seconds, but when run
> from inside a Python script I can't seem to make the damn thing not
> massively buffer its output.  Accordingly, my script doesn't really see the
> output as its emitted, so the timestamp line it prepends to a block of
> output is off.
> 
> I'm currently using subprocess.Popen like so:
> 
>     os.environ["TERM"] = "dumb"
>     cmd = "prstat -c %s" % " ".join(sys.argv[1:])
>     pipe = Popen(cmd, shell=True, bufsize=1, stdout=PIPE).stdout
> 
> I've tried these other variants as well:
> 
>   * prefacing the prstat command with unbuffer (the tcl/expect thingamabob)
> 
>   * explicitly redirect the prstat output to /dev/stdout
> 
>   * setting bufsize to 0
> 
>   * used os.popen instead of Subprocess.Popen
> 
> Nothing seems to help.  I always seem to see about 30 seconds of data at
> once (I'm currently using a 5-second interval and 10 lines of output).  I
> would have expected that prstat would simply flush stdout after each block
> of output.
> 
> Any ideas about how to get prstat to cooperate better?

Use pexpect, which will make the program believe it runs in a terminal, 
and not buffer the output.

Diez


From invalid at invalid  Mon Jul 27 15:27:47 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 27 Jul 2009 14:27:47 -0500
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<24654358.post@talk.nabble.com>
	<mailman.3791.1248721801.8015.python-list@python.org>
Message-ID: <qtOdna1pcdIuYvDXnZ2dnUVZ_t6dnZ2d@posted.visi>

On 2009-07-27, Joshua Kugler <joshua at joshuakugler.com> wrote:
> Dr. Phillip M. Feldman wrote:
>
>> "As far as I know, there is no programming language which
>> treats scalars like ints as if they were vectors of length 1"
>> 
>> Actually, Matlab does:
>> 
>>>> length(5)
>> ans =
>>      1
>>>> 
>
> Oddly enough, so does Perl:
>
> $ print length(44)
> 2

No, that's not really treating scalars as vectors of length 1.
Were it doing so, length(44) would be 1 rather than 2.  What
Perl does is treat everything as a string.

-- 
Grant Edwards                   grante             Yow! I was making donuts
                                  at               and now I'm on a bus!
                               visi.com            


From wolfgang at rohdewald.de  Mon Jul 27 15:27:55 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Mon, 27 Jul 2009 21:27:55 +0200
Subject: New implementation of re module
In-Reply-To: <4A6DD6FB.8040609@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
Message-ID: <200907272127.55328.wolfgang@rohdewald.de>

On Monday 27 July 2009, MRAB wrote:
> I've been working on a new implementation of the re module. The
> details are at http://bugs.python.org/issue2636, specifically from
> http://bugs.python.org/issue2636#msg90954. I've included a .pyd
> file for Python 2.6 on Windows if you want to try it out.

how do I compile _regex.c on Linux?

-- 
Wolfgang


From benjamin.kaplan at case.edu  Mon Jul 27 15:30:31 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Mon, 27 Jul 2009 15:30:31 -0400
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <ec96e1390907271230o491ae706v1ddc6717b9dcb363@mail.gmail.com>

On Mon, Jul 27, 2009 at 1:40 PM, Reckoner<reckoner at gmail.com> wrote:
> Hi,
>
> Observe the following:
>
> In [202]: class Foo():
> ? .....: ? ? def __init__(self,h=[]):
> ? .....: ? ? ? ? self.h=h
> ? .....:
> ? .....:
>
> In [203]: f=Foo()
>
> In [204]: g=Foo()
>
> In [205]: g.h
> Out[205]: []
>
> In [206]: f.h
> Out[206]: []
>
> In [207]: f.h.append(10)
>
> In [208]: f.h
> Out[208]: [10]
>
> In [209]: g.h
> Out[209]: [10]
>
> The question is: why is g.h updated when I append to f.h? ?Shouldn't
> g.h stay []?
>
> What am I missing here?
>
> I'm using Python 2.5.1.
>
> Thanks in advance.


. It has to do with the way Python handles functions and class
methods. Basically, when the parser creates the class Foo, it also
creates all of Foo's class variables and functions. It's at this
point, and only at this point, that the default parameter is
evaluated.

When you make an instance of Foo, just wraps the function __init__ by
filling in the initial parameter. Because both f and g are really
using the Foo.__init__ function (as opposed to separate f.__init__ and
g.__init__ methods), they share the same default parameter, a list
that was created at the very beginning.

Since f.h and g.h both refer to the same list, updating f.h will also
update g.h (and the default parameter). That's why it's a bad idea to
use mutable default parameters- use either None

class Foo(object) :
   def __init__(self, h=None) :
      if h is None:
         h = []

or, if None is an acceptable value, make a sentinel value

sentinel = object()
class Foo(object) :
   def __init__(self, h = sentinel) :
      if h is sentinel:
         h = []
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From rlichlighter at gmail.com  Mon Jul 27 15:33:21 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 12:33:21 -0700 (PDT)
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<h4k8o8$ght$00$1@news.t-online.com>
	<bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
	<h4kqd9$5h2$01$1@news.t-online.com>
Message-ID: <f1006be7-bad7-41ec-a187-792194fbcd51@y19g2000yqy.googlegroups.com>

On Jul 27, 2:07?pm, Peter Otten <__pete... at web.de> wrote:
> r2 wrote:
> > On Jul 27, 9:06 am, Peter Otten <__pete... at web.de> wrote:
> >> r2 wrote:
> >> > I have a memory dump from a machine I am trying to analyze. I can view
> >> > the file in a hex editor to see text strings in the binary code. I
> >> > don't see a way to save these ascii representations of the binary, so
> >> > I went digging into Python to see if there were any modules to help.
>
> >> > I found one I think might do what I want it to do - the binascii
> >> > module. Can anyone describe to me how to convert a raw binary file to
> >> > an ascii file using this module. I've tried? Boy, I've tried.
>
> >> That won't work because a text editor doesn't need any help to convert
> >> the bytes into characters. If it expects ascii it just will be puzzled by
> >> bytes that are not valid ascii. Also, it will happily display byte
> >> sequences that are valid ascii, but that you as a user will see as
> >> gibberish because they were meant to be binary data by the program that
> >> wrote them.
>
> >> > Am I correct in assuming I can get the converted binary to ascii text
> >> > I see in a hex editor using this module? I'm new to this forensics
> >> > thing and it's quite possible I am mixing technical terms. I am not
> >> > new to Python, however. Thanks for your help.
>
> >> Unix has the "strings" commandline tool to extract text from a binary.
> >> Get hold of a copy of the MinGW tools if you are on windows.
>
> >> Peter
>
> > Okay. Thanks for the guidance. I have a machine with Linux, so I
> > should be able to do what you describe above. Could Python extract the
> > strings from the binary as well? Just wondering.
>
> As a special service for you here is a naive implementation to build upon:
>
> #!/usr/bin/env python
> import sys
>
> wanted_chars = ["\0"]*256
> for i in range(32, 127):
> ? ? wanted_chars[i] = chr(i)
> wanted_chars[ord("\t")] = "\t"
> wanted_chars = "".join(wanted_chars)
>
> THRESHOLD = 4
>
> for s in sys.stdin.read().translate(wanted_chars).split("\0"):
> ? ? if len(s) >= THRESHOLD:
> ? ? ? ? print s
>
> Peter- Hide quoted text -
>
> - Show quoted text -

Perfect! Thanks.


From mondi at cs.unibo.it  Mon Jul 27 15:35:51 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Mon, 27 Jul 2009 19:35:51 +0000
Subject: ioctl on socket
Message-ID: <h4knsn$u76$1@lec.cs.unibo.it>

Is there a reason why there is no ioctl interface for socket either then
for windows platform? It's technical issues or what else??

thank in advance
	jacopo


From python at mrabarnett.plus.com  Mon Jul 27 16:00:48 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 27 Jul 2009 21:00:48 +0100
Subject: New implementation of re module
In-Reply-To: <4a6dfa5b$0$10245$426a74cc@news.free.fr>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<4a6dfa5b$0$10245$426a74cc@news.free.fr>
Message-ID: <4A6E0770.4000908@mrabarnett.plus.com>

William Dode wrote:
> On 27-07-2009, MRAB wrote:
>> Hi all,
>>
>> I've been working on a new implementation of the re module. The details
>> are at http://bugs.python.org/issue2636, specifically from
>> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>> Python 2.6 on Windows if you want to try it out.
>>
> 
> Someone can remember me how to compile it (on debian lenny), if possible 
> with python2.5. I've also python3.1 that i build alone...
> 
> I could test it with pytextile, i've a bunch of texts to bench and 
> compare.
> 
All I can do is point you to 
http://docs.python.org/extending/extending.html.

For Linux (which I don't have) you'll need to use _regex.h and _regex.c
to compile to _regex.so instead of _regex.pyd.

> Did you announce it on the unladen-swallow list ? They wanted to hack on 
> RE also...
> 
No. I haven't subscribed to it.


From davea at ieee.org  Mon Jul 27 16:07:16 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 16:07:16 -0400
Subject: Convert raw binary file to ascii
In-Reply-To: <bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>	<h4k8o8$ght$00$1@news.t-online.com>
	<bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
Message-ID: <4A6E08F4.8080203@ieee.org>

r2 wrote:
> On Jul 27, 9:06 am, Peter Otten <__pete... at web.de> wrote:
>   
>> r2 wrote:
>>     
>>> I have a memory dump from a machine I am trying to analyze. I can view
>>> the file in a hex editor to see text strings in the binary code. I
>>> don't see a way to save these ascii representations of the binary, so
>>> I went digging into Python to see if there were any modules to help.
>>>       
>>> I found one I think might do what I want it to do - the binascii
>>> module. Can anyone describe to me how to convert a raw binary file to
>>> an ascii file using this module. I've tried? Boy, I've tried.
>>>       
>> That won't work because a text editor doesn't need any help to convert the
>> bytes into characters. If it expects ascii it just will be puzzled by bytes
>> that are not valid ascii. Also, it will happily display byte sequences that
>> are valid ascii, but that you as a user will see as gibberish because they
>> were meant to be binary data by the program that wrote them.
>>
>>     
>>> Am I correct in assuming I can get the converted binary to ascii text
>>> I see in a hex editor using this module? I'm new to this forensics
>>> thing and it's quite possible I am mixing technical terms. I am not
>>> new to Python, however. Thanks for your help.
>>>       
>> Unix has the "strings" commandline tool to extract text from a binary.
>> Get hold of a copy of the MinGW tools if you are on windows.
>>
>> Peter
>>     
>
> Okay. Thanks for the guidance. I have a machine with Linux, so I
> should be able to do what you describe above. Could Python extract the
> strings from the binary as well? Just wondering.
>
>   
Yes, you could do the same thing in Python easily enough.  And with the 
advantage that you could define your own meanings for "characters."

The memory dump could be storing characters that are strictly ASCII.  Or 
it could have EBCDIC, or UTF-8.  And it could be Unicode, 16 bit or 32 
bits, and big-endian or little-endian.  Or the characters could be in 
some other format specific to a particular program.

However, it's probably very useful to see what a "strings" program might 
look like, because you can quickly code variations on it, to suit your 
particular data.
Something like the following (totally untested)

def isprintable(char):
    return 0x20 <= char <= 0x7f

def string(filename):
    data = open(filename, "rb").read()
    count = 0
    line = ""
    for ch in data:
        if isprintable(ch):
             count += 1
             line = line + ch
        else:
             if count > 4 :     #cutoff, don't print strings smaller 
than this because they're probably just coincidence
                 print line
                 count = 0
                 line= ""
    print line


Now you can change the definition of what's "printable", you can change 
the min-length that you care about.  And of course you can fine-tune 
things like max-length lines and such.

DaveA



From davea at dejaviewphoto.com  Mon Jul 27 16:14:14 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Mon, 27 Jul 2009 16:14:14 -0400
Subject: Help understanding the decisions *behind* python? - immutable
	objects
In-Reply-To: <ec96e1390907270541p7846d649r7d8fd6e429c64a56@mail.gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>	<mailman.3511.1248244497.8015.python-list@python.org>	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
	<ec96e1390907270541p7846d649r7d8fd6e429c64a56@mail.gmail.com>
Message-ID: <4A6E0A96.60001@dejaviewphoto.com>

Benjamin Kaplan wrote:
> On Sun, Jul 26, 2009 at 2:24 PM, John Nagle<nagle at animats.com> wrote:
>   
>> Beni Cherniavsky wrote:
>>     
>>> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
>>> wrote:
>>>       
>>>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>>> <snip>
>>> problem.
>>>       
>>    An interesting issue is Python objects, which are always mutable.
>> A "dict" of Python objects is allowed, but doesn't consider
>> the contents of the objects, just their identity (address). Only
>> built-in types are immutable; one cannot create a class of immutable
>> objects.
>> So things like "frozenset" had to be built into the language.
>> A tuple is really a frozen list.  Arguably, frozen objects
>> should have been a general concept.  Conceptually, they're
>> simple - once "__init__" has run, there can be no more changes
>> to fields of the object.
>>
>>    Compare the C++ approach, where you can have a "map" of
>> any object that defines the "<" operator.  Python has
>> "__cmp__" for objects, but built-in dictionaries don't use it.
>> Of course, one could create a "map" class in Python that
>> uses "__cmp__", which would allow dictionary-type operations
>> on arbitrary objects.
>>     
>
>
> Python dictionaries are hash maps so they use hashes, not comparisons,
> to store objects. By default the hash is equal to the object's
> identity but all you need to do to change it is define your own
> __hash__ method. If you were to make a C++ hash map, it wouldn't use
> comparisons either.
>
> <snip>
>   
>
I think you'll find that to make a proper dict of user-objects, you need 
to define not only __hash__(), but also __eq__() methods.   A hash is 
only a starting place.  In case of collision, the dict class calls 
another method to make sure.

And of course, for the dict to function reasonably, you have to make 
sure that the hash and eq functions return consistent results, at least 
pretending that the objects involved are immutable.

DaveA



From ccurvey at gmail.com  Mon Jul 27 16:16:28 2009
From: ccurvey at gmail.com (Chris Curvey)
Date: Mon, 27 Jul 2009 13:16:28 -0700 (PDT)
Subject: PyPDF and print restrictions
Message-ID: <90034475-cf07-4a57-b8cf-ec2949e0e544@d23g2000vbm.googlegroups.com>

Has anyone out there been able to enforce print restrictions on a PDF
document by using PyPDF? The documentation for "encrypt" states:

 # @param user_pwd The "user password", which allows for opening and
reading
 # the PDF file with the restrictions provided.

But there is no parameter for providing a restriction, and I can't
find a reference to any kind of restriction besides this comment in
the docs.

Thanks in advance!



From nagle at animats.com  Mon Jul 27 16:24:34 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 13:24:34 -0700
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6deda5$0$1639$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
Message-ID: <4a6e0c53$0$1644$742ec2ed@news.sonic.net>

John Nagle wrote:
> John Nagle wrote:
>> There's something strange about this URL:
>>
>> "https://sagar310.pontins.com/sraep/"
>>
>> It hangs Firefox 2; there's no short timeout, the web page just gets
>> stuck in initial load for about ten minutes.  Then
>> "The connection to sagar310.pontins.com was interrupted while the page 
>> was loading."
>>
>> It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.
> 
>     Correction: Linux is still hung at 5 hours, but Windows timed out
> after about 15 minutes.
> 
Further update: M2Crypto on Windows now hung on that URL for hours.  Last time,
the connection apparently failed and the program got unstuck.

It's waiting for something to happen inside SSL connection setup.

				John Nagle


From djames.suhanko at gmail.com  Mon Jul 27 16:25:32 2009
From: djames.suhanko at gmail.com (Djames Suhanko)
Date: Mon, 27 Jul 2009 17:25:32 -0300
Subject: Discovery IP in connection
Message-ID: <fd9e6bba0907271325i5b32060ah6930fe5db336f6ee@mail.gmail.com>

Hello,all!
 I wrote a little programa that listening UDP packets. A can receive
the messages, but I can't see the the origin IP.
 How can I to  get the remote IP address in connection?

My source:

#!/usr/bin/env python
import socket
mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
mySocket.bind ( ( '', 514 ) )

data, addr = mySocket.recvfrom(100)
print data

-- 
Djames Suhanko
LinuxUser 158.760


From 71david at libero.it  Mon Jul 27 16:35:01 2009
From: 71david at libero.it (David)
Date: Mon, 27 Jul 2009 22:35:01 +0200
Subject: Gracefully exiting CLI application
Message-ID: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>

Greetings,

I am writing a command line application, and I need to perform some cleaning
on exit even if the process is killed.
How can I do that with python?

Thank you.
David.


From erikwickstrom at gmail.com  Mon Jul 27 16:38:25 2009
From: erikwickstrom at gmail.com (erikcw)
Date: Mon, 27 Jul 2009 13:38:25 -0700 (PDT)
Subject: Download the "head" of a large file?
Message-ID: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>

I'm trying to figure out how to download just the first few lines of a
large (50mb) text file form a server to save bandwidth.  Can Python do
this?

Something like the Python equivalent of curl http://url.com/file.xml |
head -c 2048

Thanks!
Erik


From tjreedy at udel.edu  Mon Jul 27 16:47:34 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 27 Jul 2009 16:47:34 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <027d38a5$0$5185$c3e8da3@news.astraweb.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>	<877hxw4avj.fsf@benfinney.id.au>	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>	<mailman.3752.1248653417.8015.python-list@python.org>	<027d0d84$0$5185$c3e8da3@news.astraweb.com>	<mailman.3757.1248674553.8015.python-list@python.org>
	<027d38a5$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4l3p6$jgj$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Mon, 27 Jul 2009 02:02:19 -0400, Terry Reedy wrote:
> 
>> Steven D'Aprano wrote:
>>> On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:
>>>
>>>> Michal Kwiatkowski wrote:
>>>>
>>>>> The thing is I don't need the next item. I need to know if the
>>>>> generator has stopped without invoking it.
>>>> Write a one-ahead iterator class, which I have posted before, that
>>>> sets .exhausted to True when next fails.
>>>
>>> And hope that the generator doesn't have side-effects...
>> If run to exhastion, the same number of side-effects happen. The only
>> difference is that they each happen once step happpen sooner. For
>> reading a file that is irrelevant. Much else, and the iterator is not
>> just an iterator.
> 
> I believe the OP specifically said he needs to detect whether or not an 
> iterator is exhausted, without running it to exhaustion, so you shouldn't 
> assume that the generator has been exhausted.

I believe the OP said he needs to determine whether or not an iterator 
(specifically generator) is exhausted without consuming an item when it 
is not. That is slightly different. The wrapper I suggested makes that 
easy. I am obviously not assuming exhaustion when there is a .exhausted 
True/False flag to check.

There are two possible definition of 'exhausted': 1) will raise 
StopIteration on the next next() call; 2) has raised StopIteration at 
least once. The wrapper converts 2) to 1), which is to say, it obeys 
definition 1 once the underlying iteration has obeyed definition 2.

Since it is trivial to set 'exhausted=True' in the generator user code 
once StopIteration has been raised (meaning 2), I presume the OP wants 
the predictive meaning 1).

Without a iterator class wrapper, I see no way to predict what a 
generator will do (expecially, raise StopIteration the first time) 
without analyzing its code and local variable state.

I said in response to YOU that once exhaustion has occurred, then the 
same number of side effects would have occurred.

> When it comes to side-effects, timing matters.

Sometimes. And I admitted that possibility (slight garbled).

  For example, a generator
> which cleans up after it has run (deleting temporary files, closing 
> sockets, etc.) will leave the environment in a different state if run to 
> exhaustion than just before exhaustion. Even if you store the final 
> result in a one-ahead class, you haven't saved the environment, and that 
> may be significant.

Of course, an eager-beaver generator written to be a good citizen might 
well close resources as soon as it knows *they* are exhausted, long 
before *it* yields the last items from the in-memory last block read. 
For all I know, file.readlines could do such.

Assuming that is not the case, the cleanup will not happen until the 
what turns out to be the final item is requested from the wrapper. Once 
cleanup has happened, .exhausted will be set to True. If proper 
processing of even the last item requires that cleanup not have 
happened, then that and prediction of exhaustion are incompatible. One 
who wants both should write an iterator class instead of generator function.

> (Of course, it's possible that it isn't significant. Not all differences 
> make a difference.)
> 
> The best advice is, try to avoid side-effects, especially in generators.

Agreed.

Terry Jan Reedy





From davea at ieee.org  Mon Jul 27 16:53:12 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 16:53:12 -0400
Subject: where do I put resources (images, audio files) when I wrote Python
	program?
In-Reply-To: <h4ksgo$qa9$1@inews.gazeta.pl>
References: <h4ksgo$qa9$1@inews.gazeta.pl>
Message-ID: <4A6E13B8.4080806@ieee.org>

Piotrek wrote:
> Hello,
>
> I write a Python program. It will contain some images (in .png format), some
> audio files (as .ogg) etc. Now I think where should my installer put these
> files and how should I access them. What is the normal Python way of doing
> that? I think about puting these files in /usr/share/myprogram and then
> reading it the normal way (so the path "/usr/share/myprogram" would be just
> hardwired in my program). Is it the way one usually does it in Python
> program or is there any more sofisticated way?
>
>
>   
I think this question is mostly independent of the issue of what's used 
to actually install the files.

My answer is to put read-only files right with the py* files, and 
writable files in the user's space.  In the former case, you can find 
the files by parsing __file__ for one of your modules.  In the latter 
case, it's system dependent.  But I'd start with a single file which is 
put in a conventional place (for your target OS).  That will be a 
configuration file ("preferences files"), which specifies, among other 
things, where everything else will be written.  Somebody else will have 
to tell you what the Unix convention would be.

In the case of Windows, the first "file" would just be a registry 
entry.  And I wouldn't write any of the actual files till the user had 
configured things, either during installation or during the first run 
(with a File->Preferences menu setup).




From zapwireDASHgroups at yahoo.com  Mon Jul 27 17:04:20 2009
From: zapwireDASHgroups at yahoo.com (Joel Koltner)
Date: Mon, 27 Jul 2009 14:04:20 -0700
Subject: len() should always return something
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
Message-ID: <pDobm.484275$6p1.246121@en-nntp-02.dc1.easynews.com>

"Dr. Phillip M. Feldman" <pfeldman at verizon.net> wrote in message 
news:mailman.3699.1248490256.8015.python-list at python.org...
> Here's a simple-minded example:
...
> This function works fine if xs is a list of floats, but not if it is single
> float.  It can be made to work as follows:

Wow, you could substitute "Matlab" for "Python" in your post and it'd still be 
just as good. :-)




From zuo at chopin.edu.pl  Mon Jul 27 17:09:14 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Mon, 27 Jul 2009 23:09:14 +0200
Subject: Convert raw binary file to ascii
In-Reply-To: <PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>
Message-ID: <op.uxqvpolpfvx12t@jerzozwiesz.home.aster.pl>

Hello Friends,

It's my first post to python-list, so first let me introduce myself...
* my name is Jan Kaliszewski,
* country -- Poland,
* occupation -- composer (studied in F. Chopin Academy of Music @Warsaw)
                 and programmer (currently in Record System company,
                                 working on Anakonda -- ERP system for
                                 big companies [developed in Python + WX
                                 + Postgres]).

Now, to the matter...

27-07-2009 Grant Edwards <invalid at invalid.chopin.edu.pl> wrote:

> On 2009-07-27, r2 <rlichlighter at gmail.com> wrote:
>
>> I have a memory dump from a machine I am trying to analyze. I can view
>> the file in a hex editor to see text strings in the binary code. I
>> don't see a way to save these ascii representations of the binary,
>
> $ strings memdump.binary >memdump.strings
>
> $ hexdump -C memdump.binary >memdump.hex+as

Do You (r2) want to do get ASCII substrings (i.e. extract only those
pieces of file that consist of ASCII codes -- i.e. 7-bit values -- i.e in
range 0...127), or rather "possibly readable ascii representation" of
the whole file, with printable ascii characters preserved 'as is' and
not-printable/non-ascii characters being replaced with their codes
(e.g. with '\x...' notation).

If the latter, you probably want something like this:

import codecs
with open('memdump.binary', 'rb') as source:
     with open('memdump.txt', 'w') as target:
         for quasiline in codecs.iterencode(source, 'string_escape'):
             target.write(quasiline)

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From martin.hellwig at dcuktec.org  Mon Jul 27 17:12:23 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Mon, 27 Jul 2009 22:12:23 +0100
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6e0c53$0$1644$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
	<4a6e0c53$0$1644$742ec2ed@news.sonic.net>
Message-ID: <fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>

John Nagle wrote:
> John Nagle wrote:
>> John Nagle wrote:
>>> There's something strange about this URL:
>>>
>>> "https://sagar310.pontins.com/sraep/"
>>>
>>> It hangs Firefox 2; there's no short timeout, the web page just gets
>>> stuck in initial load for about ten minutes.  Then
>>> "The connection to sagar310.pontins.com was interrupted while the 
>>> page was loading."
>>>
>>> It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.
>>
>>     Correction: Linux is still hung at 5 hours, but Windows timed out
>> after about 15 minutes.
>>
> Further update: M2Crypto on Windows now hung on that URL for hours.  
> Last time,
> the connection apparently failed and the program got unstuck.
> 
> It's waiting for something to happen inside SSL connection setup.
> 
>                 John Nagle

It looks to me like the SSL handshake is not done properly from the 
server side.

Compare the output of:
openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts -msg

With (for example):
openssl s_client -host www.google.com -port 443 -debug -showcerts -msg

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From shai at platonix.com  Mon Jul 27 17:15:00 2009
From: shai at platonix.com (Shai)
Date: Mon, 27 Jul 2009 14:15:00 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<mailman.3774.1248703529.8015.python-list@python.org>
Message-ID: <c93175a3-e8fa-4e18-a10c-1516b72dcdb9@33g2000vbe.googlegroups.com>

On Jul 27, 5:05?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> Ben Finney wrote:
> >
> > The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> > applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> > the method, the original docstring is not associated with it.
>
> I've also tried within the python interpreter, and it can perfectly
> solve docstring inheritance. So why would you explicitly assign
> docstring to child methods ?
>

What do you mean by "can perfectly solve docstring inheritance" ?

After the following,

class Foo(object):
    def foo(self):
        "Frobber"
        pass

class Bar(Foo):
    def foo(self):
        pass

help(Bar.foo) does not display "Frobber" on my interpreter.



From zuo at chopin.edu.pl  Mon Jul 27 17:35:23 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Mon, 27 Jul 2009 23:35:23 +0200
Subject: Gracefully exiting CLI application
In-Reply-To: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
Message-ID: <op.uxqww9e7fvx12t@jerzozwiesz.home.aster.pl>

27-07-2009 o 22:35:01 David <71david at libero.it> wrote:

> I am writing a command line application, and I need to perform some  
> cleaning
> on exit even if the process is killed.
> How can I do that with python?

See: http://docs.python.org/library/signal.html

Cheers,
*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From constant.beta at gmail.com  Mon Jul 27 17:37:57 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Mon, 27 Jul 2009 14:37:57 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
	<mailman.3752.1248653417.8015.python-list@python.org>
	<027d0d84$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3757.1248674553.8015.python-list@python.org>
	<027d38a5$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3798.1248727674.8015.python-list@python.org>
Message-ID: <47bfd80f-2f61-462e-8789-811a2c836b5e@n2g2000vba.googlegroups.com>

On Jul 27, 10:47?pm, Terry Reedy <tjre... at udel.edu> wrote:
> There are two possible definition of 'exhausted': 1) will raise
> StopIteration on the next next() call; 2) has raised StopIteration at
> least once. The wrapper converts 2) to 1), which is to say, it obeys
> definition 1 once the underlying iteration has obeyed definition 2.
>
> Since it is trivial to set 'exhausted=True' in the generator user code
> once StopIteration has been raised (meaning 2), I presume the OP wants
> the predictive meaning 1).

No, I meant the second meaning (i.e. generator is exhausted when it
has returned instead of yielding).

While, as you showed, it is trivial to create a generator that will
have the "exhausted" flag, in my specific case I have no control over
the user code. I have to use what the Python genobject API gives me
plus the context of the trace function.

Cheers,
mk


From ben+python at benfinney.id.au  Mon Jul 27 17:40:32 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 28 Jul 2009 07:40:32 +1000
Subject: Gracefully exiting CLI application
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
Message-ID: <873a8h4xf3.fsf@benfinney.id.au>

David <71david at libero.it> writes:

> I am writing a command line application, and I need to perform some
> cleaning on exit even if the process is killed. How can I do that with
> python?

Write an ?exit handler? function, then use ?atexit.register?
<URL:http://docs.python.org/library/atexit> to register yours for
processing whenever the program exits.

-- 
 \        ?Pinky, are you pondering what I'm pondering?? ?Wuh, I think |
  `\    so, Brain, but will they let the Cranberry Duchess stay in the |
_o__)                         Lincoln Bedroom?? ?_Pinky and The Brain_ |
Ben Finney


From zuo at chopin.edu.pl  Mon Jul 27 17:52:27 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Mon, 27 Jul 2009 23:52:27 +0200
Subject: Gracefully exiting CLI application
In-Reply-To: <873a8h4xf3.fsf@benfinney.id.au>
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
	<873a8h4xf3.fsf@benfinney.id.au>
Message-ID: <op.uxqxppj9fvx12t@jerzozwiesz.home.aster.pl>

27-07-2009 Ben Finney <ben+python at benfinney.id.au> wrote:

> David <71david at libero.it> writes:
>
>> I am writing a command line application, and I need to perform some
>> cleaning on exit even if the process is killed. How can I do that with
>> python?
>
> Write an ?exit handler? function, then use ?atexit.register?
> <URL:http://docs.python.org/library/atexit> to register yours for
> processing whenever the program exits.

Unfortunately neither sys.exitfunc nor function registered with
atexit.register() are called when process is killed with signal.

As I wrote, you must use signals. Though sometimes it's a good idea
to combine these two techniques (i.e. signal handlers call sys.exit(),
then sys.exitfunc/or function registered with atexit does the actual
cleaning actions).

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From bcharrow at csail.mit.edu  Mon Jul 27 18:33:51 2009
From: bcharrow at csail.mit.edu (Ben Charrow)
Date: Mon, 27 Jul 2009 18:33:51 -0400
Subject: Download the "head" of a large file?
In-Reply-To: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
Message-ID: <4A6E2B4F.70102@csail.mit.edu>

erikcw wrote:
> ...download just the first few lines of a large (50mb) text file form a
> server to save bandwidth..... Something like the Python equivalent of curl
> http://url.com/file.xml | head -c 2048

If you're OK calling curl and head from within python:

from subprocess import Popen, PIPE
url = "http://docs.python.org/"
p1 = Popen(["curl", url], stdout = PIPE, stderr = PIPE)
p2 = Popen(["head", "-c", "1024"], stdin = p1.stdout, stdout = PIPE)
p2.communicate()[0]

If you want a pure python approach:

import urllib2
url = "http://docs.python.org/"
req = urllib2.Request(url)
f = urllib2.urlopen(req)
f.read(1024)

HTH,
Ben


From gallium.arsenide at gmail.com  Mon Jul 27 18:40:25 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Mon, 27 Jul 2009 15:40:25 -0700 (PDT)
Subject: Download the "head" of a large file?
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
Message-ID: <5579245f-b8cb-44cc-9b5f-1e7009422a58@g19g2000vbi.googlegroups.com>

On Jul 27, 4:38?pm, erikcw <erikwickst... at gmail.com> wrote:
> I'm trying to figure out how to download just the first few lines of a
> large (50mb) text file form a server to save bandwidth. ?Can Python do
> this?
>
> Something like the Python equivalent of curlhttp://url.com/file.xml|
> head -c 2048

urllib.urlopen gives you a file-like object, which you can then read
line by line or in fixed-size chunks.  For example:

import urllib
chunk = urllib.urlopen('http://url.com/file.xml').read(2048)

At that point, chunk is just bytes, which you can write to a local
file, print, or whatever it is you want.

John


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 27 19:00:27 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 27 Jul 2009 23:00:27 GMT
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
Message-ID: <027e226c$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 15:23:41 -0300, Gabriel Genellina wrote:

> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson
> <jakecjacobson at gmail.com> escribi?:
> 
>> I was wondering if this is due to the server having a invalid server
>> cert?  If I go to this server in my browser, I get a "This server tried
>> to identify itself with invalid information".  Is there a way to ignore
>> this issue with Python?  Can I setup a trust store and add this server
>> to the trust store?
> 
> I don't see the point in trusting someone that you know is telling lies
> about itself.

Don't you? It's just commonsense risk assessment.

It's far more likely that the server has an incorrectly setup certificate 
managed by an incompetent sys admin than it is that somebody is eaves-
dropping on my connection to https://somerandom.site.com/something-trivial

Particularly when the connection is on my own intranet and I know the sys 
admin in question has made a mistake and the new certificate is scheduled 
to be installed "some time next week". *wink*

Of course, if there was sensitive information involved, or money, then 
I'd be more concerned.


-- 
Steven


From gherron at islandtraining.com  Mon Jul 27 19:06:36 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Mon, 27 Jul 2009 16:06:36 -0700
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <4A6E32FC.4080202@islandtraining.com>

Reckoner wrote:
> Hi,
>
> Observe the following:
>
> In [202]: class Foo():
>    .....:     def __init__(self,h=[]):
>    .....:         self.h=h
>    .....:
>    .....:
>
> In [203]: f=Foo()
>
> In [204]: g=Foo()
>
> In [205]: g.h
> Out[205]: []
>
> In [206]: f.h
> Out[206]: []
>
> In [207]: f.h.append(10)
>
> In [208]: f.h
> Out[208]: [10]
>
> In [209]: g.h
> Out[209]: [10]
>
> The question is: why is g.h updated when I append to f.h?  Shouldn't
> g.h stay []?
>
> What am I missing here?
>
> I'm using Python 2.5.1.
>
> Thanks in advance.
>   

This is a FAQ (and *very* common newbie trap)!  See:

  
http://www.python.org/doc/faq/general/#why-are-default-values-shared-between-objects

Gary Herron



From drobinow at gmail.com  Mon Jul 27 19:07:06 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 27 Jul 2009 18:07:06 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4kepl$qhf$1@panix3.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
Message-ID: <4eb0089f0907271607m1dd34f39qaec04a650afdd31f@mail.gmail.com>

On Mon, Jul 27, 2009 at 9:49 AM, Aahz<aahz at pythoncraft.com> wrote:
> In article <mailman.3765.1248685391.8015.python-list at python.org>,
> Hendrik van Rooyen ?<hendrik at microcorp.co.za> wrote:
>>On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>
>>> ?I'm a mediocre programmer. Does this mean I should switch to PHP?
>>
>>I have searched, but I can find nothing about this mediocre language.
>>
>>Could you tell us more?
>
> (For anyone who is confused by Hendrik's humor, he is saying that David
> was referring to a programming language named "mediocre". ?English
> grammar is confusing!)
 Well, Aahz, I think it rather rude to spoil the fun with your explanation.
Just for that, I'm not going to post any mediocre code. You'll have to
figure it out yourself.
(Q:   should the name of my favorite language be capitalized?)


From roy at panix.com  Mon Jul 27 19:21:43 2009
From: roy at panix.com (Roy Smith)
Date: Mon, 27 Jul 2009 19:21:43 -0400
Subject: Discovery IP in connection
References: <mailman.3797.1248726749.8015.python-list@python.org>
Message-ID: <roy-8412BB.19214327072009@news.panix.com>

In article <mailman.3797.1248726749.8015.python-list at python.org>,
 Djames Suhanko <djames.suhanko at gmail.com> wrote:

> Hello,all!
>  I wrote a little programa that listening UDP packets. A can receive
> the messages, but I can't see the the origin IP.
>  How can I to  get the remote IP address in connection?
> 
> My source:
> 
> #!/usr/bin/env python
> import socket
> mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
> mySocket.bind ( ( '', 514 ) )
> 
> data, addr = mySocket.recvfrom(100)
> print data

What happens when you print addr?


From piet at cs.uu.nl  Mon Jul 27 19:23:13 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 01:23:13 +0200
Subject: Discovery IP in connection
References: <mailman.3797.1248726749.8015.python-list@python.org>
Message-ID: <m2ws5taexq.fsf@cs.uu.nl>

>>>>> Djames Suhanko <djames.suhanko at gmail.com> (DS) wrote:

>DS> Hello,all!
>DS>  I wrote a little programa that listening UDP packets. A can receive
>DS> the messages, but I can't see the the origin IP.
>DS>  How can I to  get the remote IP address in connection?

What do you think the addr is for in 
data, addr = mySocket.recvfrom(100)?

>DS> My source:

>DS> #!/usr/bin/env python
>DS> import socket
>DS> mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
>DS> mySocket.bind ( ( '', 514 ) )

>DS> data, addr = mySocket.recvfrom(100)
>DS> print data

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From david.lyon at preisshare.net  Mon Jul 27 19:53:00 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Mon, 27 Jul 2009 19:53:00 -0400
Subject: Using =?UTF-8?Q?easy=5Finstall=2C=20reduncant=3F?=
In-Reply-To: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
References: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
Message-ID: <8ae7c63db1dfcc3bbc1619b67939a5d5@preisshare.net>

On Mon, 27 Jul 2009 09:42:06 -0700 (PDT), ray <Ray.Joseph at CDICorp.com>
wrote:
> I am working on a Trac installation.  I am new to Python.  To install
> packages, it is suggested to use setuptools.  I have not understood
> the directions.
> 
> I execute ez_install.py.
> 
> Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
> There response that setuptools is already the active version in easy-
> install.pth.  Then:
> Installing easy_install.exe script to C:\Python26\Scripts error:  C:
> \Python26\Scripts\Easy_install.exe: Permission denied.
> 
> I have compared the file entries before and after this attempt and
> there are no new files.  Is there any problems here?  What did I miss?

Try using python package manager :
http://sourceforge.net/projects/pythonpkgmgr/

You might find it a lot simpler. It will download and install setuptools
for you if you are still having problems.

David


From r1chardj0n3s at gmail.com  Mon Jul 27 20:34:52 2009
From: r1chardj0n3s at gmail.com (Richard Jones)
Date: Tue, 28 Jul 2009 10:34:52 +1000
Subject: Next meeting: Tuesday 11th August
Message-ID: <1680A969-5DD9-4A2C-BACB-9B342C44123C@gmail.com>

The next meeting of the Melbourne Python Users Group will be on  
Tuesday the 11th of August starting at 6:30pm. We'll be meeting at  
Horse Bazaar again but this time we'll have use of their projector.  
We'll have time for several short presentations or lightning talks.

Meeting details, location and talks list are at:

   http://wiki.python.org/moin/MelbournePUG

If you've seen something cool or are doing something cool then we'd  
like you to tell everyone about it! Presentations could be 5 minutes  
or up to 15 minutes if you'd like to ramble for a bit longer. I'll be  
getting up to talk a bit about my experiences playing with IronPython  
- what's cool and what's downright odd :)

If you've got an idea for a talk just add it to the wiki page.


     Richard



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 20:46:51 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 21:46:51 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<157f16f9-2172-4fd5-8ec8-8d9569a3f186@f20g2000prn.googlegroups.com>
Message-ID: <op.uxq5sdfcx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 15:52:08 -0300, jakecjacobson  
<jakecjacobson at gmail.com> escribi?:

> On Jul 27, 2:23?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson ?
>> <jakecjacob... at gmail.com> escribi?:
>>
>> > I was wondering if this is due to the server having a invalid server
>> > cert? ?If I go to this server in my browser, I get a "This server
>> > tried to identify itself with invalid information". ?Is there a way to
>> > ignore this issue with Python? ?Can I setup a trust store and add this
>> > server to the trust store?
>>
>> I don't see the point in trusting someone that you know is telling lies  
>> about itself.
>
> It is a test box that the team I am on runs.  That is why I would
> trust it.

I'd fix the certificate issue on the server. Or use plain HTTP if it's  
just for testing.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:16:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:16:39 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <op.uxq6brfjx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 20:00:27 -0300, Steven D'Aprano
<steve at remove-this-cybersource.com.au> escribi?:
> On Mon, 27 Jul 2009 15:23:41 -0300, Gabriel Genellina wrote:
>> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson
>> <jakecjacobson at gmail.com> escribi?:
>>
>>> I was wondering if this is due to the server having a invalid server
>>> cert?  If I go to this server in my browser, I get a "This server tried
>>> to identify itself with invalid information".  Is there a way to ignore
>>> this issue with Python?  Can I setup a trust store and add this server
>>> to the trust store?
>>
>> I don't see the point in trusting someone that you know is telling lies
>> about itself.
>
> Don't you? It's just commonsense risk assessment.
>
> It's far more likely that the server has an incorrectly setup certificate
> managed by an incompetent sys admin than it is that somebody is eaves-
> dropping on my connection to  
> https://somerandom.site.com/something-trivial

Fire the sys admin then :)
I don't see the point on "fixing" either the Python script or httplib to
accomodate for an invalid server certificate... If it's just for internal
testing, I'd use HTTP instead (at least until the certificate is fixed).

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:16:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:16:42 -0300
Subject: Download the "head" of a large file?
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
	<5579245f-b8cb-44cc-9b5f-1e7009422a58@g19g2000vbi.googlegroups.com>
Message-ID: <op.uxq7lqixx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 19:40:25 -0300, John Yeung
<gallium.arsenide at gmail.com> escribi?:

> On Jul 27, 4:38?pm, erikcw <erikwickst... at gmail.com> wrote:
>> I'm trying to figure out how to download just the first few lines of a
>> large (50mb) text file form a server to save bandwidth. ?Can Python do
>> this?
>>
>> Something like the Python equivalent of curlhttp://url.com/file.xml|
>> head -c 2048
>
> urllib.urlopen gives you a file-like object, which you can then read
> line by line or in fixed-size chunks.  For example:
>
> import urllib
> chunk = urllib.urlopen('http://url.com/file.xml').read(2048)
>
> At that point, chunk is just bytes, which you can write to a local
> file, print, or whatever it is you want.

As the OP wants to save bandwidth, it's better to ask exactly the amount
of data to read. That is, add a Range header field [1] to the request, and
inspect the response for a corresponding Content-Range header [2].

py> import urllib2
py> url = "http://www.python.org/"
py> req = urllib2.Request(url)
py> req.add_header('Range', 'bytes=0-10239')  # first 10K
py> f = urllib2.urlopen(req)
py> data = f.read()
py> print repr(data[-30:]), len(data)
'\t    <a href="http://www.zope.' 10240
py> f.headers['Content-Range']
'bytes 0-10239/18196'
py> f.getcode()
206            # 206=Partial Content
py> f.close()

[1] http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35

[2] http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.16

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:16:48 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:16:48 -0300
Subject: ioctl on socket
References: <h4knsn$u76$1@lec.cs.unibo.it>
Message-ID: <op.uxq8xesrx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 16:35:51 -0300, jacopo mondi <mondi at cs.unibo.it>
escribi?:

> Is there a reason why there is no ioctl interface for socket either then
> for windows platform? It's technical issues or what else??

I don't completely understand your question. On Windows, you can use
socket.ioctl with sockets, and DeviceIoControl (from the pywin32 package)
with other files. On Linux, you have fcntl.ioctl that works with any kind
of file.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:17:18 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:17:18 -0300
Subject: where do I put resources (images, audio files) when I wrote
	Python program?
References: <h4ksgo$qa9$1@inews.gazeta.pl> <4A6E13B8.4080806@ieee.org>
Message-ID: <op.uxq8a1g6x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 17:53:12 -0300, Dave Angel <davea at ieee.org> escribi?:
> Piotrek wrote:
>>
>> I write a Python program. It will contain some images (in .png format),  
>> some
>> audio files (as .ogg) etc. Now I think where should my installer put  
>> these
>> files and how should I access them. What is the normal Python way of  
>> doing
>> that? I think about puting these files in /usr/share/myprogram and then
>> reading it the normal way (so the path "/usr/share/myprogram" would be  
>> just
>> hardwired in my program). Is it the way one usually does it in Python
>> program or is there any more sofisticated way?
>>
>>
> My answer is to put read-only files right with the py* files, and  
> writable files in the user's space.  In the former case, you can find  
> the files by parsing __file__ for one of your modules.  In the latter  
> case, it's system dependent.

For those read-only resources I'd use pkgutil.get_data (instead of
manually parsing __file__):

http://docs.python.org/library/pkgutil.html#pkgutil.get_data

It's easier to manage when someone later decide to install the package as
an egg file, or distribute it using py2exe. Quoting the documentation:

"""The function returns a binary string that is the contents of the
specified resource.

For packages located in the filesystem, which have already been imported,
this is the rough equivalent of:

d = os.path.dirname(sys.modules[package].__file__)
data = open(os.path.join(d, resource), 'rb').read()
return data
"""

-- 
Gabriel Genellina



From doug.farrell at gmail.com  Mon Jul 27 22:52:01 2009
From: doug.farrell at gmail.com (writeson)
Date: Mon, 27 Jul 2009 19:52:01 -0700 (PDT)
Subject: Extract images from PDF files
Message-ID: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>

Hi all,

I've looked around with Google quite a bit, but haven't found anything
like what I'm looking for. Is there a Python library that will extract
images from PDF files? My ultimate goal is to pull the images out, use
the PIL library to reduce the size of the images and rebuild another
PDF file that's an essentially "thumbnail" version of the original PDF
file, smaller in size.

We've been using imagick to extract the images, but it's difficult to
script and slow to process the input PDF. Can someone suggest
something better?

Thanks in advance,
Doug


From aahz at pythoncraft.com  Mon Jul 27 22:52:26 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 19:52:26 -0700
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <h4lp5a$ehd$1@panix3.panix.com>

In article <mailman.3787.1248712420.8015.python-list at python.org>,
MRAB  <python at mrabarnett.plus.com> wrote:
>
>I've been working on a new implementation of the re module. The details
>are at http://bugs.python.org/issue2636, specifically from
>http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>Python 2.6 on Windows if you want to try it out.

How does it handle the re module's unit tests?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From dmw at coder.cl  Mon Jul 27 23:02:47 2009
From: dmw at coder.cl (Daniel Molina Wegener)
Date: Mon, 27 Jul 2009 23:02:47 -0400
Subject: [ANN] pyxser-1.1r --- python xml serialization
Message-ID: <u5KdnZcPYu0_9_PXnZ2dnUVZ_hydnZ2d@giganews.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

Hello,

I'm pleased to announce pyxser-1.1r, a Python-Object to XML
serializer and deserializer. This package it's completly
written in C and licensed under LGPLv3.

The tested Python versions are 2.5.X and 2.7.X.

* home page:
  http://coder.cl/software/pyxser

* hosted at:
  http://sourceforge.net/projects/pyxser/

The current ChangeLog is as follows:

- -----8<----------8<----------8<----------8<-----
1.1r (2009.05.09):

        Daniel Molina Wegener <dmw at coder.cl>
        * Removed bugs concerning XML schema declaration for output
        documents.
        * Removed bugs concerning XML schema design for C14N
        serialization.
        * Removed exc argument from C14N serialization functions,
        because they have no sense.
        * Code cleanup with function arguments (C code).
        * All changes seems to be transparent for previous versions.
- -----8<----------8<----------8<----------8<-----

Also, I need a little bit of feedback. I want it to be able to
serialize files and buffers: I've planned to allow the user
to have three options: ignore files, serialize them in base64
encoding and just put the file name as string. But my question
concerns how the files and buffers are deserialized: I must
allow the user to dump the files on a directory, put the complete
file on a buffer object, or just extract the base64 encoded
block?

Best regards and thanks in advance...
- -- 
 .O. | Daniel Molina Wegener   | FreeBSD & Linux
 ..O | dmw [at] coder [dot] cl | Open Standards
 OOO | http://coder.cl/        | FOSS Developer

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (FreeBSD)
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=7sXN
-----END PGP SIGNATURE-----


From huzaigang at cn.panasonic.com  Mon Jul 27 23:06:06 2009
From: huzaigang at cn.panasonic.com (jammy)
Date: Tue, 28 Jul 2009 11:06:06 +0800
Subject: How to get the output struct parameter by extending C function?
Message-ID: <006a01ca0f30$59849b30$af97c20a@psdcd.local>

Hello,

I an just starting to use the ctypes module.
Now I want to expentd C in python.
In the function of C, I want to get the  output struct parameter which 
is chaged in the function.
following is my code:

----------- 1.Header file of C?information.h?-----------
typedef struct {
 char  name[20];
 int   height;
 int   weight;
} Infor;
int getInfor( char* name, int height, int weight, Infor* infor);


----------- 2.Source file of C?information.c?-----------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "Extest.h"
int getInfor( char* name, int height, int weight, Infor* infor)
{
    if(name == NULL || infor == NULL)
        return (-1);

    printf("  [%s] get params: name[%s] height[%d] weight[%d]\n", 
__FUNCTION__, name, height, weight);
    strcpy(infor->name, name);
    infor->height = height;
    infor->weight = weight;
    return (1);
}


----------- 3.information.c's warp file for Python calling?information_wrap.c?----------- 

#include "Python.h"
#include "ceval.h"
#include "Extest.h"

static PyObject * Extest_getInfor(PyObject *self, PyObject *args)
{
    char* name;
    int height;
    int weight;
    Infor* infor;
    int res;

    if(!PyArg_ParseTuple(args, "siiO:infor", &name, &height, &weight, 
&infor)){
         return NULL;
    }

    printf(" ***** Before Call: infor.name[%s] infor.height[%d] 
infor.weight[%d] *****\n",infor->name, infor->height, 
infor->weight);//[1]initial value
    res = getInfor(name, height, weight, infor);
    printf(" ***** After Call: infor.name[%s] infor.height[%d] 
infor.weight[%d] *****\n", infor->name, infor->height, 
infor->weight);//[2]changed value

    return (PyObject*)Py_BuildValue("i", res);
}

static PyMethodDef ExtestMethods[] = {
    { "getInfor", Extest_getInfor, METH_VARARGS },
    { NULL, NULL },
};

void initExtest(void)
{
    PyObject *m;
    m = Py_InitModule("Extest", ExtestMethods);
}


----------- 4.Makefile-----------
# Makefile of Extend C for Python
OBJS          = Extest.o ExtestWrappers.o
TARGET      = Extest.so
INCLUDES   = -I /usr/local/include/python2.6/
MAKEFILE   = Makefile
CC             = gcc
CFLAGS      = -fPIC -Wall -Wstrict-prototypes -Winline \
                    ${INCLUDES} -O2
all : ${TARGET}
${TARGET} : ${OBJS} ${LIBS}
    ${CC} -shared -o ${TARGET} ${OBJS}
    rm -f ${OBJS}
clean :
    rm -f *.o *.Z* *~ ${TARGET}


----------- 5.test file of Python?test.py?-----------
#!/usr/bin/env python2.6
#coding=utf8

import Extest
from ctypes import *

class Infor(Structure):
    _fields_= [('name', c_char*20),
    ('height', c_int),
    ('weight', c_int)]

def main():
    infor = Infor()
    infor.name = 'NoName'
    infor.height = -1
    infor.weight = -1

    name = 'TestName'
    height = 175
    weight = 160

    print 'Before call getInfor(), Infor.name=%s  Infor.height=%d 
Infor.weight=%d' % (infor.name, infor.height, infor.weight)
    Extest.getInfor(name, height, weight, byref(infor))
    print 'After call getInfor(), Infor.name=%s  Infor.height=%d 
Infor.weight=%d' % (infor.name, infor.height, infor.weight) [3]want to 
get value of infor changed
    print ' ----- all DONE -----'

if __name__ == '__main__':
    main()

----------- 6.result of running test.py -----------
[root at localhost obj_struct_test]# ./test.py
Before call getInfor(), Infor.name=NoName  Infor.height=-1 
Infor.weight=-1
sizeof(*infor)=28, sizeof(Infor)=28
        ***** [Extest_getInfor] Before Call: infor.name[] 
infor.height[0] infor.weight[0] *****
                [getInfor] get params: name[TestName] height[175] 
weight[160]
        ***** [Extest_getInfor] After Call: infor.name[TestName] 
infor.height[175] infor.weight[160] *****
After call getInfor(), Infor.name=NoName  Infor.height=-1 
Infor.weight=-1
 ----- all DONE -----

Looking for the printed information, in the file of 
information_wrap.c(setp 3), In the comment 's tag[2], printed value is 
changed valuse.
Why  is the printed Information initial value atfer calling getInfor() 
in test.py?
Thanks for your help!

                                                                       
                       yours: jammy 



From mobiledreamers at gmail.com  Mon Jul 27 23:31:25 2009
From: mobiledreamers at gmail.com (mobiledreamers at gmail.com)
Date: Mon, 27 Jul 2009 20:31:25 -0700
Subject: [Baypiggies] Egnyte: hiring
In-Reply-To: <20090728024611.GA4649@panix.com>
References: <20090728024611.GA4649@panix.com>
Message-ID: <c1870d60907272031i2413f84bu2b00cb52ba2a8cac@mail.gmail.com>

Seems interesting
http://fotoroll.com/searchvideo?q=vineet%20jain,%20ceo%20of%20egnyte&id=0&type=video

<http://fotoroll.com/searchvideo?q=vineet%20jain,%20ceo%20of%20egnyte&id=0&type=video>

On Mon, Jul 27, 2009 at 7:46 PM, Aahz <aahz at pythoncraft.com> wrote:

> My new company (I just started today) closed a big venture capital round
> (also today) and is looking to hire more people, preferably with Python
> experience:
>
> Senior Linux Engineer:
> http://sfbay.craigslist.org/pen/sof/1292008176.html
>
> Senior Platforms Engineer:
> http://sfbay.craigslist.org/pen/sof/1291776907.html
>
> Venture announcement:
> http://blogs.zdnet.com/BTL/?p=21777
>
> I can't say a lot about the company myself yet, but I've gotten a good
> impression of the team and the business plan.  Find out more here:
> http://www.egnyte.com/
> --
> Aahz (aahz at pythoncraft.com)           <*>
> http://www.pythoncraft.com/
>
> "Many customs in this life persist because they ease friction and promote
> productivity as a result of universal agreement, and whether they are
> precisely the optimal choices is much less important." --Henry Spencer
> _______________________________________________
> Baypiggies mailing list
> Baypiggies at python.org
> To change your subscription options or unsubscribe:
> http://mail.python.org/mailman/listinfo/baypiggies
>



-- 
Bidegg worlds best auction site
http://bidegg.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090727/04e3e280/attachment.html>

From david.lyon at preisshare.net  Mon Jul 27 23:37:39 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Mon, 27 Jul 2009 23:37:39 -0400
Subject: Extract images from PDF files
In-Reply-To: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
Message-ID: <e55aa5912cc63888ddc2f52c8404bbe2@preisshare.net>


pdftohtml on sourceforge may help...

On Mon, 27 Jul 2009 19:52:01 -0700 (PDT), writeson <doug.farrell at gmail.com>
wrote:
> Hi all,
> 
> I've looked around with Google quite a bit, but haven't found anything
> like what I'm looking for. Is there a Python library that will extract
> images from PDF files? My ultimate goal is to pull the images out, use
> the PIL library to reduce the size of the images and rebuild another
> PDF file that's an essentially "thumbnail" version of the original PDF
> file, smaller in size.
> 
> We've been using imagick to extract the images, but it's difficult to
> script and slow to process the input PDF. Can someone suggest
> something better?
> 
> Thanks in advance,
> Doug


From himanshu.garg at gmail.com  Tue Jul 28 00:22:29 2009
From: himanshu.garg at gmail.com (++imanshu)
Date: Mon, 27 Jul 2009 21:22:29 -0700 (PDT)
Subject: _msi.Record object has no attribute 'GetString'
References: <32e0b242-8635-40b5-a366-2c9967e64e1c@d4g2000yqa.googlegroups.com>
Message-ID: <2392afa6-59fe-4c98-8c12-403222a8ee24@a37g2000prf.googlegroups.com>

On Jul 27, 4:38?pm, "++imanshu" <himanshu.g... at gmail.com> wrote:
> The documentation (http://docs.python.org/library/msilib.html#record-
> objects) for msilib mentions the GetString() method on Record objects.
> However, the following snippet :-
>
> db = msilib.OpenDatabase(os.path.join(root, file),
> msilib.MSIDBOPEN_READONLY)
> view = db.OpenView('SELECT * FROM Property')
> view.Execute(None)
> r = view.Fetch()
> print dir(r)
> print r.GetString(0)
>
> gives me this error :-
>
> c:\>python msi.py
> ['ClearData', 'GetFieldCount', 'SetInteger', 'SetStream', 'SetString',
> __class__', '__delattr__', '__doc__', '__getattribute__', '__hash__',
> '__init__', '__new__', __reduce__', '__reduce_ex__', '__repr__',
> '__setattr__', '__str__']
> Traceback (most recent call last):
> ? File "msi.py", line 18, in <module>
> ? ? print r.GetString(0)
> AttributeError: '_msi.Record' object has no attribute 'GetString'
>
> Am I missing something?

Known Issue. Already fixed here http://mail.python.org/pipermail/python-bugs-list/2008-February/047136.html



From gagsl-py2 at yahoo.com.ar  Tue Jul 28 00:34:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 01:34:42 -0300
Subject: How to get the output struct parameter by extending C function?
References: <006a01ca0f30$59849b30$af97c20a@psdcd.local>
Message-ID: <op.uxrgb4fax6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 00:06:06 -0300, jammy <huzaigang at cn.panasonic.com>  
escribi?:

> I an just starting to use the ctypes module.
> Now I want to expentd C in python.
> In the function of C, I want to get the  output struct parameter which  
> is chaged in the function.

You're mixing a C extension with a ctypes call - why is that?
ctypes is mainly used when you *don't* want to actually write a C  
extension - if you actually write one, you don't need ctypes at all.

> ----------- 1.Header file of C(information.h)-----------
> typedef struct {
>  char  name[20];
>  int   height;
>  int   weight;
> } Infor;
> int getInfor( char* name, int height, int weight, Infor* infor);

> ----------- 5.test file of Python(test.py)-----------
>     Extest.getInfor(name, height, weight, byref(infor))

All arguments for a function intended to be called from Python must be  
PyObject*; byref is used to call a ctypes-wrapped function, not a function  
 from an extension module. (You're lucky you didn't crash the interpreter  
process)

Either use ctypes to directly call the getInfor function in information.c  
(and drop the extension module), or write a complete wrapper in the  
extension module and forget ctypes. Don't mix both ways.

-- 
Gabriel Genellina



From doron.tal.list at gmail.com  Tue Jul 28 00:37:35 2009
From: doron.tal.list at gmail.com (Doron Tal)
Date: Tue, 28 Jul 2009 07:37:35 +0300
Subject: Gracefully exiting CLI application
In-Reply-To: <op.uxqxppj9fvx12t@jerzozwiesz.home.aster.pl>
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
	<873a8h4xf3.fsf@benfinney.id.au>
	<op.uxqxppj9fvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <2a8674c60907272137u6df107b7v25c73d0e4a8a9821@mail.gmail.com>

On Tue, Jul 28, 2009 at 12:52 AM, Jan Kaliszewski <zuo at chopin.edu.pl> wrote:

> As I wrote, you must use signals. Though sometimes it's a good idea
> to combine these two techniques (i.e. signal handlers call sys.exit(),
> then sys.exitfunc/or function registered with atexit does the actual
> cleaning actions).


Another way of combining signals and atexit functions is to write a signal
handlers which update some QUIT_APP flag, which the application polls on
occasionally. This way you'll avoid deadlocks which may happen if you have a
multi-threaded application, and your main thread had just acquired a lock.

--doron
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/1dd4b317/attachment.html>

From brenNOSPAMbarn at NObrenSPAMbarn.net  Tue Jul 28 00:41:34 2009
From: brenNOSPAMbarn at NObrenSPAMbarn.net (OKB (not okblacke))
Date: Tue, 28 Jul 2009 04:41:34 GMT
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <Xns9C55DCA902C61OKB@199.45.49.11>

MRAB wrote:

> http://bugs.python.org/issue2636#msg90954

    	Variable-length lookbehind!  My hero!

-- 
--OKB (not okblacke)
Brendan Barnwell
"Do not follow where the path may lead.  Go, instead, where there is
no path, and leave a trail."
	--author unknown


From janssen at parc.com  Tue Jul 28 01:45:23 2009
From: janssen at parc.com (Bill Janssen)
Date: Mon, 27 Jul 2009 22:45:23 PDT
Subject: new version of SSL module on PyPI
Message-ID: <2029.1248759923@parc.com>

I've uploaded ssl-1.15.tgz, the backport of the 2.6/3.x SSL module to
Python 2.3-2.5.  It provides an option for not using SSLv2, and also
fixes a bug with write retries.

Bill


From hekevintran at gmail.com  Tue Jul 28 02:02:30 2009
From: hekevintran at gmail.com (Kevin)
Date: Mon, 27 Jul 2009 23:02:30 -0700 (PDT)
Subject: Error in compiling Python on OS X
References: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>
	<7d44lbF29p3p7U1@mid.uni-berlin.de>
Message-ID: <5535080f-30ba-473c-8710-8752bf745e70@p36g2000prn.googlegroups.com>

On Jul 26, 3:46?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Kevin schrieb:
>
> > I am trying to compile Python 2.6.2 on Mac OS X 10.5.7. ?I have Xcode
> > 3.1.3 installed.
>
> > The error I got is below.
>
> > $ ./configure --prefix=/Users/me/python
>
> Use a framework-build.
>
> > checking for --with-universal-archs... 32-bit
> > checking MACHDEP... darwin
> > checking EXTRAPLATDIR... $(PLATMACDIRS)
> > checking machine type as reported by uname -m... i386
> > checking for --without-gcc... no
> > checking for gcc... gcc
> > checking for C compiler default output file name...
> > configure: error: C compiler cannot create executables
> > See `config.log' for more details.
>
> > Please send any ideas.
>
> What happens if you write a simple test.c like this:
>
> int main() {
> ? ? return 0;
>
> }
>
> and compile it with gcc on the commandline? There must be a file called
> "a.out" afterwards.
>
> diez

I have solved my problem.  I think something was wrong with my
compiler.  After I installed Xcode again, I was able to compile with
no problems.


From bcharrow at csail.mit.edu  Tue Jul 28 02:18:37 2009
From: bcharrow at csail.mit.edu (Ben Charrow)
Date: Tue, 28 Jul 2009 02:18:37 -0400
Subject: Download the "head" of a large file?
In-Reply-To: <h4m3pc$q7m$1@ger.gmane.org>
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
	<h4m3pc$q7m$1@ger.gmane.org>
Message-ID: <4A6E983D.20707@csail.mit.edu>

Dennis Lee Bieber wrote:
> On Mon, 27 Jul 2009 13:38:25 -0700 (PDT), erikcw
> <erikwickstrom at gmail.com> declaimed the following in
> gmane.comp.python.general:
>> Something like the Python equivalent of curl http://url.com/file.xml |
>> head -c 2048
>>
> 	Presuming that | is a shell pipe operation, then doesn't that
> command line use "curl" to download the entire file, and "head" to
> display just the first 2k?

No, the entire file is not downloaded.  My understanding of why this is (which 
could be wrong) is that the output of curl is piped to head, and once head gets 
the first 2k it closes the pipe.  Then, when curl tries to write to the pipe 
again, it gets sent the SIGPIPE signal at which point it exits.

Cheers,
Ben


From paul.paj at gmail.com  Tue Jul 28 02:21:10 2009
From: paul.paj at gmail.com (Paul Johnston)
Date: Mon, 27 Jul 2009 23:21:10 -0700 (PDT)
Subject: Determining __name__ from the code that called a function
Message-ID: <edf221e9-3538-4d84-8a6f-28074b567fdb@x5g2000prf.googlegroups.com>

Hi,

In ToscaWidgets 2 experimental, when defining resources you often do
something like this:
CSSLink(modname=__name__, filename='static/mycss.css')

Now, what I'd like to do is make the "modname=__name__" optional, to
make code more concise. I figure there must be some way (using inspect
or something) to determine what __name__ would be in the code that
just called my function. Couldn't immediately see how to do this - any
suggestions? Thanks,

Paul


From gagsl-py2 at yahoo.com.ar  Tue Jul 28 02:45:52 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 03:45:52 -0300
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>
Message-ID: <op.uxrmeqdox6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 21:49:26 -0300, Naoki INADA <songofacandy at gmail.com>  
escribi?:


>>> The encoding that this file uses. When Unicode strings are written to  
>>> a file,
>>>  they will be converted to byte strings using this encoding. In  
>>> addition,
>>> when the file is connected to a terminal, the attribute gives the  
>>> encoding
>>> that the terminal is likely to use
>
> I feel this doc means "file object with encoding attribute encodes
> unicode
> regardless it is tty or not" and sys.stdout/stderr defies convention.

The 'encoding' file attribute is very confusing and mostly unsupported (or  
there is a bug in the documentation, at least in Python 2.x). See  
http://bugs.python.org/issue4947

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Tue Jul 28 02:46:00 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 03:46:00 -0300
Subject: exceptions.TypeError an integer is required
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
	<0279f85d$0$5185$c3e8da3@news.astraweb.com>
	<8d03a739-7e45-49e1-b93d-6a396beed877@a37g2000prf.googlegroups.com>
Message-ID: <op.uxrmeyayx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 12:44:40 -0300, jakecjacobson  
<jakecjacobson at gmail.com> escribi?:
>
> You are quite correct in your statements.  My goal was not to make
> great code but something that I could quickly test.  My assumption was
> that the httplib.HTTPSConnection() would do the cast to int for me.
> As soon as I cast it to an int, I was able to get past that issue.

A few remarks that may help learning the language:

Note that Python is a strongly typed (and dynamic) language. All objects  
have a defined type: "443" is not the same thing as 443, and "2" + 2  
raises a TypeError.

If a function expects an integer, you must provide an integer (or  
something that at least "acts" as an integer; a string isn't  
"integer-alike" at all from Python's POV)

Also, you don't "cast" an object into another: the expression int("443")  
is a constructor, and it returns a new object (an integer) based upon its  
argument. (so it's quite different from, say, casting "short" to "unsigned  
short" in C, that only changes the way the compiler treats the same bytes  
in memory).

-- 
Gabriel Genellina



From guitarzero at gmail.com  Tue Jul 28 03:18:43 2009
From: guitarzero at gmail.com (guitarzero)
Date: Tue, 28 Jul 2009 00:18:43 -0700 (PDT)
Subject: WSDL and XML generation
Message-ID: <3be39c48-6a89-4542-b08a-eaf00933b184@c1g2000yqi.googlegroups.com>

Hi all
Newbie in Python, i am looking for some pointers (or better existing
modules) to do the followings:

- generate (correct) XML messages from a WSDL file
- make some modifications inside XML messages *before* sending them to
the server hosting the Web services (described by previously
mentionned WSDL file)
- parse the answer.

Some ideas ?
Thanks in advance
Stephane


From oripel at gmail.com  Tue Jul 28 03:23:10 2009
From: oripel at gmail.com (orip)
Date: Tue, 28 Jul 2009 00:23:10 -0700 (PDT)
Subject: Testoob: How do you use testoob.collector_from_globals / 
	collector_from_modules?
References: <1a8582cc-a7fc-4b1e-b1b2-d23e20ad6022@18g2000yqa.googlegroups.com>
Message-ID: <0972bcba-a18c-4e33-9605-8955f723bd51@d32g2000yqh.googlegroups.com>

Hi Harry,

I forwarded this to the Testoob list at http://groups.google.com/group/testoob

Ori.

On Jul 27, 4:12?pm, Harry Ebbers <neme... at gmail.com> wrote:
> Hi,
>
> For a project I'm creating unittests using testoob. When all tests are
> in a single file there is no problem
>
> if __name__ == '__main__':
> ? ? testoob.main()
> ?does the trick as usual.
>
> But for a number of python-applications they have asked me to group
> unittests in different files, based on common functionality (e.g. GUI,
> main-application, etcetera).
>
> Ican get it to work by importing all unittestclasses in the following
> way and than use the normal if __name__ == '__main__' construction
>
> (from GUI import GUItests
> from APP import APPtests
>
> if __name__ == '__main__':
> ? ? testoob.main())
>
> But looking at the future I would like to use testsuites.
>
> On the internet I found the functions testoob.collector_from_globals
> and collector_from_modules which one can use to 'easily' create
> testsuites which can be used with testoob. But no examples on how to
> use them can be found.
>
> Can anybody supply me with a working example?
>
> TIA
>
> Harry Ebbers



From nick at craig-wood.com  Tue Jul 28 03:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Tue, 28 Jul 2009 02:29:56 -0500
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
Message-ID: <slrnh6t7lt.o4a.nick@irishsea.home.craig-wood.com>

jakecjacobson <jakecjacobson at gmail.com> wrote:
>  I am getting the following error when doing a post to REST API,
> 
>  Enter PEM pass phrase:
>  Traceback (most recent call last):
>    File "./ices_catalog_feeder.py", line 193, in ?
>      main(sys.argv[1])
>    File "./ices_catalog_feeder.py", line 60, in main
>      post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
>  (input_dir, file), collection_name, key_file, cert_file)
>    File "./ices_catalog_feeder.py", line 125, in post2Catalog
>      connection.request('POST', path, parameters, head)
>    File "/usr/lib/python2.4/httplib.py", line 810, in request
>      self._send_request(method, url, body, headers)
>    File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
>      self.endheaders()
>    File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
>      self._send_output()
>    File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
>      self.send(msg)
>    File "/usr/lib/python2.4/httplib.py", line 652, in send
>      self.connect()
>    File "/usr/lib/python2.4/httplib.py", line 1079, in connect
>      ssl = socket.ssl(sock, self.key_file, self.cert_file)
>    File "/usr/lib/python2.4/socket.py", line 74, in ssl
>      return _realssl(sock, keyfile, certfile)
>  socket.sslerror: (1, 'error:14094412:SSL
>  routines:SSL3_READ_BYTES:sslv3 alert bad certificate')
> 
> 
>  My code where this error occurs is:
> 
>  head = {"Content-Type" : "application/x-www-form-urlencoded",
>  "Accept" : "text/plain"}
>  parameters = urlencode({"collection" : collection, "entryxml" : open
>  (file,'r').read()})
>  print "Sending the file to: " + host
> 
>  try:
>  	try:
>  		# Default port is 443.
>  		# key_file is the name of a PEM formatted file that contains your
>  private key.
>  		# cert_file is a PEM formatted certificate chain file.
>  		connection = httplib.HTTPSConnection(host, int(port), key_file,
>  cert_file)
>  		connection.request('POST', path, parameters, head)
>  		response = connection.getresponse()
>  		print response.status, response.reason
>  	except httplib.error, (value,message):
>  		print value + ':' + message
>  finally:
>  	connection.close()
> 
>  I was wondering if this is due to the server having a invalid server
>  cert?

I'd say judging from the traceback you messed up key_file or cert_file
somehow.

Try using the openssl binary on them (read the man page to see how!)
to check them out.

>  If I go to this server in my browser, I get a "This server tried to
>  identify itself with invalid information".  Is there a way to
>  ignore this issue with Python?  Can I setup a trust store and add
>  this server to the trust store?

Invalid how?  Self signed certificate? Domain mismatch? Expired certificate?

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From mal at egenix.com  Tue Jul 28 03:30:23 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Tue, 28 Jul 2009 09:30:23 +0200
Subject: RSA cryptography between Python and Java
In-Reply-To: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
Message-ID: <4A6EA90F.1030000@egenix.com>

Rob Knop wrote:
> I've created an RSA key in Java.  I have exported the public key by
> making it into a X509EncodedKeySpec and spitting out the result of
> getEncoded().
> 
> I want to use this public key to encode something in python that I will
> send to Java, and then decode in Java with the corresponding private
> key.
> 
> Are there any python libraries that will take a public key in this
> format and do RSA encoding on it?

M2Crypto will let you do this:

    http://chandlerproject.org/bin/view/Projects/MeTooCrypto

If you have access to the raw key data (instead of having it
encoded in a X509 certificate), then you can also use PyCrypto,
which does require setting up OpenSSL first:

    http://www.dlitz.net/software/pycrypto/

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 28 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From gagsl-py2 at yahoo.com.ar  Tue Jul 28 03:40:03 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 04:40:03 -0300
Subject: Determining __name__ from the code that called a function
References: <edf221e9-3538-4d84-8a6f-28074b567fdb@x5g2000prf.googlegroups.com>
Message-ID: <op.uxrow1sbx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 03:21:10 -0300, Paul Johnston <paul.paj at gmail.com>  
escribi?:

> In ToscaWidgets 2 experimental, when defining resources you often do
> something like this:
> CSSLink(modname=__name__, filename='static/mycss.css')
>
> Now, what I'd like to do is make the "modname=__name__" optional, to
> make code more concise. I figure there must be some way (using inspect
> or something) to determine what __name__ would be in the code that
> just called my function. Couldn't immediately see how to do this - any
> suggestions?

In CPython, you may use sys._getframe(1).f_globals['__name__'] but I don't  
know how portable is that across Python implementations.

-- 
Gabriel Genellina



From marco at sferacarta.com  Tue Jul 28 04:18:57 2009
From: marco at sferacarta.com (Marco Mariani)
Date: Tue, 28 Jul 2009 10:18:57 +0200
Subject: where do I put resources (images, audio files) when I wrote Python
	program?
In-Reply-To: <h4ksgo$qa9$1@inews.gazeta.pl>
References: <h4ksgo$qa9$1@inews.gazeta.pl>
Message-ID: <Svybm.564$I16.98@tornado.fastwebnet.it>

Piotrek wrote:

> that? I think about puting these files in /usr/share/myprogram and then
> reading it the normal way (so the path "/usr/share/myprogram" would be just
> hardwired in my program). Is it the way one usually does it in Python
> program or is there any more sofisticated way?

Just keep them in your sources, and create an empty __init__.py file in 
the images directory.
Then install setuptools and use the pkg_resources module. It will work 
even if your application is installed as an egg through easy_install, 
possibly zipped.


To open a resource file:

f = pkg_resources.resource_stream('path.to.package', 'resource.png')
f.read()


"""
     Return a readable file-like object for the specified resource; it 
may be an actual file, a StringIO, or some similar object. The stream is 
in "binary mode", in the sense that whatever bytes are in the resource 
will be read as-is.
"""


From niklasro at gmail.com  Tue Jul 28 04:26:57 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 01:26:57 -0700 (PDT)
Subject: The longest word
Message-ID: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>

Newbie hello onwards to the .py manual asks meantime how the longest
word gets determined?
First word, ok
 'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
'a'
rfind is another subset
>>> 'a aa aaa aa'[:'a aa aaa aa'.rfind(' ',1,10)]
'a aa aaa'
One row should be able. It's a direct word 'a aa aaa...' and can be a
variable, it's no big deal it occurs twice still naturally easier if
also occured just once.
Sincere thanks & regards
Niklas


From hendrik at microcorp.co.za  Tue Jul 28 04:35:48 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Tue, 28 Jul 2009 10:35:48 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4kepl$qhf$1@panix3.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
Message-ID: <200907281035.48713.hendrik@microcorp.co.za>

On Monday 27 July 2009 16:49:25 Aahz wrote:
> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>
> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
> >On Sunday 26 July 2009 21:26:46 David Robinow wrote:
> >>  I'm a mediocre programmer. Does this mean I should switch to PHP?
> >
> >I have searched, but I can find nothing about this mediocre language.
> >
> >Could you tell us more?
> >
> :-P
>
> (For anyone who is confused by Hendrik's humor, he is saying that David
> was referring to a programming language named "mediocre".  English
> grammar is confusing!)

This is true - I intended, when I started the post, to make a crack about
how he knew that he was mediocre - If there were some exam or test
that you have to pass or fail to be able to make the claim to mediocrity.
I was imagining a sort of devil's rating scale for programmers, that
could cause one to say things like:  "I am studying hard so that I can
get my mediocre certificate, and one day I hope to reach hacker rank".

And then the similarity to "I am a COBOL programmer" struck me, 
and I abandoned the ratings.

- Hendrik



From bearophileHUGS at lycos.com  Tue Jul 28 05:02:23 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 28 Jul 2009 02:02:23 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
Message-ID: <99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>

On Jul 28, 10:26?am, NiklasRTZ <nikla... at gmail.com> wrote:
> Newbie hello onwards to the .py manual asks meantime how the longest
> word gets determined?
> First word, ok
> ?'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]

Your language is not easy to understand, but I think you want to find
the longest word in a string.
If this is the input string:
txt = "a aa aaa aa"

There are several ways to do it, I'll show a simple one.

You can split it into its parts (not having Python a built-in lazy
split yet, you can split it all at once). You can do it with the
string split method. It produces a list of the words, more or less
(but you may have words like "gone,", you may have to take care of
them too, this requires some code.

Once you have a list of words, you have to take the longest. A simple
way is to replace each word with a tuple that contains the length of
the word and the word itself, then pick the tuple with the highest
length value. But Python allows you to do such operation in a faster
way: you can use the max() function, it has a "key" function that
allows you to remap on the fly what you mean by "max". So you just
have to give it a function (reference) that given the word spits its
length, such function is "len" itself.

If you instead want to find the position of the longest word the
program gets a little longer. Ask if you need something different.

Bye,
bearophile


From niklasro at gmail.com  Tue Jul 28 05:22:53 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 02:22:53 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
Message-ID: <aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>

On Jul 28, 5:02?am, Bearophile <bearophileH... at lycos.com> wrote:
> On Jul 28, 10:26?am, NiklasRTZ <nikla... at gmail.com> wrote:
>
> > Newbie hello onwards to the .py manual asks meantime how the longest
> > word gets determined?
> > First word, ok
> > ?'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
>
> Your language is not easy to understand, but I think you want to find
> the longest word in a string.
> If this is the input string:
> txt = "a aa aaa aa"
>
> There are several ways to do it, I'll show a simple one.
>
> You can split it into its parts (not having Python a built-in lazy
> split yet, you can split it all at once). You can do it with the
> string split method. It produces a list of the words, more or less
> (but you may have words like "gone,", you may have to take care of
> them too, this requires some code.
>
> Once you have a list of words, you have to take the longest. A simple
> way is to replace each word with a tuple that contains the length of
> the word and the word itself, then pick the tuple with the highest
> length value. But Python allows you to do such operation in a faster
> way: you can use the max() function, it has a "key" function that
> allows you to remap on the fly what you mean by "max". So you just
> have to give it a function (reference) that given the word spits its
> length, such function is "len" itself.
>
> If you instead want to find the position of the longest word the
> program gets a little longer. Ask if you need something different.
>
> Bye,
> bearophile

Thank you. This seems to work:
sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
len(b))[-1]
'sdfsdfsdfsdf'


From piet at cs.uu.nl  Tue Jul 28 05:24:37 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 11:24:37 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
Message-ID: <m2r5w19n3e.fsf@cs.uu.nl>

>>>>> NiklasRTZ <niklasro at gmail.com> (N) wrote:

>N> Newbie hello onwards to the .py manual asks meantime how the longest
>N> word gets determined?
>N> First word, ok
>N>  'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
>N> 'a'
>N> rfind is another subset
>>>>> 'a aa aaa aa'[:'a aa aaa aa'.rfind(' ',1,10)]
>N> 'a aa aaa'
>N> One row should be able. It's a direct word 'a aa aaa...' and can be a
>N> variable, it's no big deal it occurs twice still naturally easier if
>N> also occured just once.
>N> Sincere thanks & regards
>N> Niklas

1. Is this homework?
2. It sounds very confusing. Are you trying to find the longest word in
   a series of words seperated by spaces? find and rfind will not help
   you much. You should start with var.split() if var contains the text.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jeanmichel at sequans.com  Tue Jul 28 05:33:43 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 28 Jul 2009 11:33:43 +0200
Subject: Override a method but inherit the docstring
In-Reply-To: <c93175a3-e8fa-4e18-a10c-1516b72dcdb9@33g2000vbe.googlegroups.com>
References: <87r5wggm0y.fsf@benfinney.id.au>	<mailman.3774.1248703529.8015.python-list@python.org>
	<c93175a3-e8fa-4e18-a10c-1516b72dcdb9@33g2000vbe.googlegroups.com>
Message-ID: <4A6EC5F7.9090402@sequans.com>

Shai wrote:
> On Jul 27, 5:05 pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
> wrote:
>   
>> Ben Finney wrote:
>>     
>>> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>>> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>>> the method, the original docstring is not associated with it.
>>>       
>> I've also tried within the python interpreter, and it can perfectly
>> solve docstring inheritance. So why would you explicitly assign
>> docstring to child methods ?
>>
>>     
>
> What do you mean by "can perfectly solve docstring inheritance" ?
>
> After the following,
>
> class Foo(object):
>     def foo(self):
>         "Frobber"
>         pass
>
> class Bar(Foo):
>     def foo(self):
>         pass
>
> help(Bar.foo) does not display "Frobber" on my interpreter.
>
>   
You're right. I must have made some dumb mistake. So interpreters do not 
solve docstring inheritance, Epydoc does.

JM


From piet at cs.uu.nl  Tue Jul 28 05:36:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 11:36:46 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>
Message-ID: <m2my6p9mj5.fsf@cs.uu.nl>

>>>>> NiklasRTZ <niklasro at gmail.com> (N) wrote:

>N> Thank you. This seems to work:
>N> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
>N> len(b))[-1]
>N> 'sdfsdfsdfsdf'

simpler:

sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '), key=len)[-1]
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mondi at cs.unibo.it  Tue Jul 28 06:05:43 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Tue, 28 Jul 2009 10:05:43 +0000
Subject: ioctl on socket
In-Reply-To: <mailman.3811.1248747906.8015.python-list@python.org>
References: <h4knsn$u76$1@lec.cs.unibo.it>
	<mailman.3811.1248747906.8015.python-list@python.org>
Message-ID: <h4marm$4j5$1@lec.cs.unibo.it>

Gabriel Genellina wrote:
> En Mon, 27 Jul 2009 16:35:51 -0300, jacopo mondi <mondi at cs.unibo.it>
> escribi?:
> 
>> Is there a reason why there is no ioctl interface for socket either then
>> for windows platform? It's technical issues or what else??
> 
> I don't completely understand your question. On Windows, you can use
> socket.ioctl with sockets, and DeviceIoControl (from the pywin32 package)
> with other files. On Linux, you have fcntl.ioctl that works with any kind
> of file.
> 
Ok, thanks a lot, my question was because I didn't know about
fcntl.ioct, I thought that ioctl wrapping was implemented inside
socketmodule.c as 'bind', 'connect', 'accept' etc. are, and I was
disoriented because no documentation for socket usage on Linux nor the
code have references about ioctl, except for windows.

I hope the reason why you didn't completely understood my question is
not my english, if it be so I'm sorry and I ask anyone to correct me,
it's the only way to improve ;)

thanks a lot
	jacopo


From user at example.net  Tue Jul 28 06:07:46 2009
From: user at example.net (superpollo)
Date: Tue, 28 Jul 2009 12:07:46 +0200
Subject: Extract images from PDF files
In-Reply-To: <mailman.3815.1248752499.8015.python-list@python.org>
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
	<mailman.3815.1248752499.8015.python-list@python.org>
Message-ID: <4a6ecdf3$0$40015$4fafbaef@reader3.news.tin.it>

David Lyon wrote:
> pdftohtml on sourceforge may help...
> 

also see: http://linuxcommand.org/man_pages/pdfimages1.html

bye


From __peter__ at web.de  Tue Jul 28 06:14:34 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 28 Jul 2009 12:14:34 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>
Message-ID: <h4mj25$6g5$00$2@news.t-online.com>

NiklasRTZ wrote:

> On Jul 28, 5:02 am, Bearophile <bearophileH... at lycos.com> wrote:
>> On Jul 28, 10:26 am, NiklasRTZ <nikla... at gmail.com> wrote:
>>
>> > Newbie hello onwards to the .py manual asks meantime how the longest
>> > word gets determined?
>> > First word, ok
>> > 'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
>>
>> Your language is not easy to understand, but I think you want to find
>> the longest word in a string.
>> If this is the input string:
>> txt = "a aa aaa aa"
>>
>> There are several ways to do it, I'll show a simple one.
>>
>> You can split it into its parts (not having Python a built-in lazy
>> split yet, you can split it all at once). You can do it with the
>> string split method. It produces a list of the words, more or less
>> (but you may have words like "gone,", you may have to take care of
>> them too, this requires some code.
>>
>> Once you have a list of words, you have to take the longest. A simple
>> way is to replace each word with a tuple that contains the length of
>> the word and the word itself, then pick the tuple with the highest
>> length value. But Python allows you to do such operation in a faster
>> way: you can use the max() function, it has a "key" function that
>> allows you to remap on the fly what you mean by "max". So you just
>> have to give it a function (reference) that given the word spits its
>> length, such function is "len" itself.
>>
>> If you instead want to find the position of the longest word the
>> program gets a little longer. Ask if you need something different.
>>
>> Bye,
>> bearophile
> 
> Thank you. This seems to work:
> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
> len(b))[-1]
> 'sdfsdfsdfsdf'

To spell out bearophile's more efficient suggestion:

>>> max("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(), key=len)
'sdfsdfsdfsdf'





From niklasro at gmail.com  Tue Jul 28 06:23:58 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 03:23:58 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com> 
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com> 
	<h4mj16$6g5$00$1@news.t-online.com>
Message-ID: <8a6313a3-5575-4195-a318-b823af0682fc@e11g2000yqo.googlegroups.com>

There were 3 solutions. Everybody's homework is someone's "what's
this?"
max('asdasfd faop29v8 asejrhjhw  awg5w35g   aw3g5aw3g
kajhsdkfhlskjdhfakljsdhf awg3   aw3'.split(), key=len)
sorted("a AAA aa aaaaa sdfsdfsdfsdf vv".split(' '),key=len)[-1]
sorted("a AAA aa aaaaa vv".split(' '),lambda a,b: len(a)-len(b))[-1]


From jakecjacobson at gmail.com  Tue Jul 28 06:35:55 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Tue, 28 Jul 2009 03:35:55 -0700 (PDT)
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<slrnh6t7lt.o4a.nick@irishsea.home.craig-wood.com>
Message-ID: <c2d97820-1168-4a1d-9abc-958f073d607f@o15g2000yqm.googlegroups.com>

On Jul 28, 3:29?am, Nick Craig-Wood <n... at craig-wood.com> wrote:
> jakecjacobson <jakecjacob... at gmail.com> wrote:
> > ?I am getting the following error when doing a post to REST API,
>
> > ?Enter PEM pass phrase:
> > ?Traceback (most recent call last):
> > ? ?File "./ices_catalog_feeder.py", line 193, in ?
> > ? ? ?main(sys.argv[1])
> > ? ?File "./ices_catalog_feeder.py", line 60, in main
> > ? ? ?post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
> > ?(input_dir, file), collection_name, key_file, cert_file)
> > ? ?File "./ices_catalog_feeder.py", line 125, in post2Catalog
> > ? ? ?connection.request('POST', path, parameters, head)
> > ? ?File "/usr/lib/python2.4/httplib.py", line 810, in request
> > ? ? ?self._send_request(method, url, body, headers)
> > ? ?File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
> > ? ? ?self.endheaders()
> > ? ?File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
> > ? ? ?self._send_output()
> > ? ?File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
> > ? ? ?self.send(msg)
> > ? ?File "/usr/lib/python2.4/httplib.py", line 652, in send
> > ? ? ?self.connect()
> > ? ?File "/usr/lib/python2.4/httplib.py", line 1079, in connect
> > ? ? ?ssl = socket.ssl(sock, self.key_file, self.cert_file)
> > ? ?File "/usr/lib/python2.4/socket.py", line 74, in ssl
> > ? ? ?return _realssl(sock, keyfile, certfile)
> > ?socket.sslerror: (1, 'error:14094412:SSL
> > ?routines:SSL3_READ_BYTES:sslv3 alert bad certificate')
>
> > ?My code where this error occurs is:
>
> > ?head = {"Content-Type" : "application/x-www-form-urlencoded",
> > ?"Accept" : "text/plain"}
> > ?parameters = urlencode({"collection" : collection, "entryxml" : open
> > ?(file,'r').read()})
> > ?print "Sending the file to: " + host
>
> > ?try:
> > ? ?try:
> > ? ? ? ? ? ?# Default port is 443.
> > ? ? ? ? ? ?# key_file is the name of a PEM formatted file that contains your
> > ?private key.
> > ? ? ? ? ? ?# cert_file is a PEM formatted certificate chain file.
> > ? ? ? ? ? ?connection = httplib.HTTPSConnection(host, int(port), key_file,
> > ?cert_file)
> > ? ? ? ? ? ?connection.request('POST', path, parameters, head)
> > ? ? ? ? ? ?response = connection.getresponse()
> > ? ? ? ? ? ?print response.status, response.reason
> > ? ?except httplib.error, (value,message):
> > ? ? ? ? ? ?print value + ':' + message
> > ?finally:
> > ? ?connection.close()
>
> > ?I was wondering if this is due to the server having a invalid server
> > ?cert?
>
> I'd say judging from the traceback you messed up key_file or cert_file
> somehow.
>
> Try using the openssl binary on them (read the man page to see how!)
> to check them out.
>
> > ?If I go to this server in my browser, I get a "This server tried to
> > ?identify itself with invalid information". ?Is there a way to
> > ?ignore this issue with Python? ?Can I setup a trust store and add
> > ?this server to the trust store?
>
> Invalid how? ?Self signed certificate? Domain mismatch? Expired certificate?
>
> --
> Nick Craig-Wood <n... at craig-wood.com> --http://www.craig-wood.com/nick

Nick,

Thanks for the help on this.  I will check my steps on openssl again
and see if I messed up.  What I tried to do was:
1.  Save my PKI cert to disk.  It was saved as a P12 file
2.  Use openssl to convert it to the needed .pem file type
3.  Saved the CA that my cert was signed by as a .crt file

These are the 2 files that I was using for key_file and
 * cert_file -> CA
 * key_file -> my PKI cert converted to a .pem file

"Invalid how?  Self signed certificate? Domain mismatch? Expired
certificate?"  It is a server name mismatch.

For everyone that wants to discuss why we shouldn't do this, great but
I can't change the fact that I need to do this.  I can't use http or
even get a correct cert at this time.  This is a quick a dirty project
to demonstrate capability.  I need something more than slide show
briefs.


From davea at ieee.org  Tue Jul 28 06:43:16 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 28 Jul 2009 06:43:16 -0400
Subject: where do I put resources (images, audio files) when I wrote
	Python program?
In-Reply-To: <op.uxq8a1g6x6zn5v@lepton.softlabbsas.com.ar>
References: <h4ksgo$qa9$1@inews.gazeta.pl> <4A6E13B8.4080806@ieee.org>
	<op.uxq8a1g6x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A6ED644.7000805@ieee.org>

Gabriel Genellina wrote:
> For those read-only resources I'd use pkgutil.get_data (instead of
> manually parsing __file__):
>
> http://docs.python.org/library/pkgutil.html#pkgutil.get_data
>
> It's easier to manage when someone later decide to install the package as
> an egg file, or distribute it using py2exe. Quoting the documentation:
>
> """The function returns a binary string that is the contents of the
> specified resource.
>
> For packages located in the filesystem, which have already been imported,
> this is the rough equivalent of:
>
> d = os.path.dirname(sys.modules[package].__file__)
> data = open(os.path.join(d, resource), 'rb').read()
> return data
> """
>
Thanks Gabriel, I hadn't come across get_data() yet.

DaveA


From gagsl-py2 at yahoo.com.ar  Tue Jul 28 06:56:27 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 07:56:27 -0300
Subject: ioctl on socket
References: <h4knsn$u76$1@lec.cs.unibo.it>
	<mailman.3811.1248747906.8015.python-list@python.org>
	<h4marm$4j5$1@lec.cs.unibo.it>
Message-ID: <op.uxrx0dhtx6zn5v@gabriel.sleipnir-bsas>

En Tue, 28 Jul 2009 07:05:43 -0300, jacopo mondi <mondi at cs.unibo.it>  
escribi?:
> Gabriel Genellina wrote:
>> En Mon, 27 Jul 2009 16:35:51 -0300, jacopo mondi <mondi at cs.unibo.it>
>> escribi?:
>>
>>> Is there a reason why there is no ioctl interface for socket either  
>>> then
>>> for windows platform? It's technical issues or what else??
>>
>> I don't completely understand your question. On Windows, you can use
>> socket.ioctl with sockets, and DeviceIoControl (from the pywin32  
>> package)
>> with other files. On Linux, you have fcntl.ioctl that works with any  
>> kind
>> of file.
>>
> Ok, thanks a lot, my question was because I didn't know about
> fcntl.ioct, I thought that ioctl wrapping was implemented inside
> socketmodule.c as 'bind', 'connect', 'accept' etc. are, and I was
> disoriented because no documentation for socket usage on Linux nor the
> code have references about ioctl, except for windows.

I see; socket.ioctl should menction fcntl.ioctl; I'll submit a  
documentation patch.

-- 
Gabriel Genellina



From hniksic at xemacs.org  Tue Jul 28 07:03:54 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 28 Jul 2009 13:03:54 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>
	<m2my6p9mj5.fsf@cs.uu.nl>
Message-ID: <87prblul0l.fsf@busola.homelinux.net>

Piet van Oostrum <piet at cs.uu.nl> writes:

>>>>>> NiklasRTZ <niklasro at gmail.com> (N) wrote:
>
>>N> Thank you. This seems to work:
>>N> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
>>N> len(b))[-1]
>>N> 'sdfsdfsdfsdf'
>
> simpler:
>
> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '), key=len)[-1]

There is no need to sort the sequence to obtain the largest element.
The max function is designed to do exactly that, and also supports the
key argument:

>>> max("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '), key=len)
'sdfsdfsdfsdf'


From Ray.Joseph at CDICorp.com  Tue Jul 28 07:54:00 2009
From: Ray.Joseph at CDICorp.com (ray)
Date: Tue, 28 Jul 2009 04:54:00 -0700 (PDT)
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org> 
	<m21vo2czeb.fsf@cs.uu.nl> <468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com> 
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com> 
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com> 
	<mailman.3784.1248709156.8015.python-list@python.org>
Message-ID: <b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>

On Jul 27, 10:39?am, David Cournapeau <courn... at gmail.com> wrote:
> On Tue, Jul 28, 2009 at 12:28 AM, Dotan Cohen<dotanco... at gmail.com> wrote:
> >> It is neither efficient or inefficient: it is just a distribution
> >> tool, to deploy python software in a form familiar to most windows
> >> users. It does not make it any faster than running the software under
> >> a python prompt.
>
> >> As much as I like python for scientific programming, I would say
> >> python is pretty far from the stated requirements in the posted blog
> >> post. It is difficult to deploy software written with python (much
> >> better than the alternatives, though), and it is slow if you can't
> >> leverage numpy/scipy (where vectorization does not apply).
>
> >> It remains to be seen whether it will be true in practice, but
> >> something like F#, with its integration in VS 2010, seems much closer
> >> IMHO. It is compiled, high level language, and backed by the biggest
> >> software vendor in the world.
>
> > The blog post is not looking to distribute his code, but he would like
> > it to be cross platform for his own reasons. VB is not cross platform.
>
> I understand his "efficient binary as Ansi C" partially as a
> deployment requirement, and independent of cross-platform issues. As a
> scientist, being able to share my software with colleagues is a non
> trivial matter. Python does not make this easy today.
>
> F# has nothing to do with VB: F# is a ML-language inspired from OCAML,
> and run on top of the CLR. It can thus leverage the huge .net
> framework (lack of non numerical API is one of the biggest matlab
> hindrance, and comparatively big advantage of python + numpy/scipy),
> and benefits from the much more efficient implementation compared to
> python (under the currently CPython implementation at least).
>
> Some recent F# versions are compatible with mono, making it compatible
> on most platforms that matter today for research (but of course, you
> lose the IDE integration outside windows).
>
> David- Hide quoted text -
>
> - Show quoted text -
I wish . . .

For comparisons, Mathcad has the symbolic notation appropriate for
mathematical communications.  I like features of Mathematica and Maple
but Mathcad provides for the user to 'stay' with mathematical
symbolism longer.  I prefer Matlab execution environment.  So I
develop concepts in Mathcad, prove them in Matlab and then compile to
through C where direct performance is required.  Maple and Matlab have
this type of relation.

Matlab, from The Mathworks, has a companion product called Simulink.
This allows the user to graphically build ?algorithms? in block form.
There is a similar Python function.

Each of these components would best be served if allowed to exist
independently but supported with transparent integration.  I would
like to develop in a stable user environment - a stable GUI.  And then
allow efficient algorithms behind the scenes.

By separating the functionality of the workspace, the user can be
given (or create at will) a GUI that suites her desires and provides
for the creativity and productivity she chooses.  The functionality
under the GUI should then be pluggable.  Developers can provide
solutions from many directions, compete for varying performance
requirements, enhance functional features technology changes, and
still not disturb the fragile user interface.

Allow the user the comfort of home.  Let them keep whatever GUI suits
them and provide for their deployment (if any) needs behind the
scenes.

Ray






From niklasro at gmail.com  Tue Jul 28 07:55:26 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 04:55:26 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com> 
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com> 
	<m2my6p9mj5.fsf@cs.uu.nl> <87prblul0l.fsf@busola.homelinux.net>
Message-ID: <c8ff2ba2-b62b-40e8-ae7e-b78cac491812@s31g2000yqs.googlegroups.com>

On Jul 28, 7:03?am, Hrvoje Niksic <hnik... at xemacs.org> wrote:
> Piet van Oostrum <p... at cs.uu.nl> writes:
>
> >>>>>> NiklasRTZ <nikla... at gmail.com> (N) wrote:
>
> >>N> Thank you. This seems to work:
> >>N> sorted("a AAA aa aaaaa ?sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
> >>N> len(b))[-1]
> >>N> 'sdfsdfsdfsdf'
>
> > simpler:
>
> > sorted("a AAA aa aaaaa ?sdfsdfsdfsdf vv".split(' '), key=len)[-1]
>
> There is no need to sort the sequence to obtain the largest element.
> The max function is designed to do exactly that, and also supports the
> key argument:
>
> >>> max("a AAA aa aaaaa ?sdfsdfsdfsdf vv".split(' '), key=len)
>
> 'sdfsdfsdfsdf'

Sincere thanks for strengthening python's superior flexibility. Same
function also works around an exploding index problem returning
results for longest word where otherwise a word with whitespace
crashes the index:
all().search(max(q.split(), key=len)).filter("modified >",
timeline).filter("published =", True).filter("modified <=",
bookmark ).order("-modified").fetch(PAGESIZE+1)
Line below crashes the index for words with whitespace (unknown
researchable, only occurs live, works with development)
all().search(q).filter("modified >", timeline).filter("published =",
True).filter("modified <=", bookmark ).order("-modified").fetch
(PAGESIZE+1)
best regards,
Niklas


From tommy.nordgren at comhem.se  Tue Jul 28 07:58:32 2009
From: tommy.nordgren at comhem.se (Tommy Nordgren)
Date: Tue, 28 Jul 2009 13:58:32 +0200
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
	<50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
Message-ID: <E982B034-D069-4878-BAE6-51F467E7407B@comhem.se>


On Jul 26, 2009, at 10:37 AM, Chris Rebert wrote:

> On Sun, Jul 26, 2009 at 1:12 AM, Jessica R
> Smith<jessica.1980.smith at gmail.com> wrote:
>> Hello,
>> I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7
>>
>> I downloaded python 2.6.2 from here:
>>  - http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2
>>
>> I unpacked it.
>>
>> I ran these shell commands:
>>  - ./configure --prefix=/pt/p
>>  - make
>>
>> Near the end of the make output I see this message:
>>
>> . Failed to find the necessary bits to build these modules:
>> . _bsddb             gdbm               linuxaudiodev
>> . ossaudiodev        readline           spwd
>> . sunaudiodev
>> . To find the necessary bits, look in setup.py in detect_modules()  
>> for
>> the module's name.
>>
>> I looked in setup.py in detect_modules()
>>
>> It is not clear to me how to proceed.
>>
>> I think that I want the module: "readline"
>>
>> I doubt I need the other modules like linuxaudiodev, etc.
>>
>> If you have any clues or opinions on how I can build the module
>> "readline",
>> please feel free to share.
>
> You need to install the GNU Readline library
> (http://tiswww.case.edu/php/chet/readline/rltop.html), which the
> module depends on.
>
	A better solution would be to configure the modules in question to use
the libreadline.dylib library already installed on every Mac OS X  
computer.
> You might consider installing Python through MacPorts or Fink instead,
> as they automate the compilation and installation process and take
> care of dependencies (such as GNU Readline) for you:
> http://www.macports.org/
> http://www.finkproject.org/
>
> Cheers,
> Chris
> -- 
> http://blog.rebertia.com
> -- 
> http://mail.python.org/mailman/listinfo/python-list

-----------------------------------
See the amazing new SF reel: Invasion of the man eating cucumbers from  
outer space.
On congratulations for a fantastic parody, the producer replies :  
"What parody?"

Tommy Nordgren
tommy.nordgren at comhem.se






From steve at REMOVE-THIS-cybersource.com.au  Tue Jul 28 08:02:40 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 28 Jul 2009 12:02:40 GMT
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3812.1248748204.8015.python-list@python.org>
Message-ID: <027ed9be$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 23:16:39 -0300, Gabriel Genellina wrote:

> I don't see the point on "fixing" either the Python script or httplib to
> accomodate for an invalid server certificate... If it's just for
> internal testing, I'd use HTTP instead (at least until the certificate
> is fixed).

In real life, sometimes you need to drive with bad brakes on your car, 
walk down dark alleys in the bad part of town, climb a tree without a 
safety line, and use a hammer without wearing goggles. We can do all 
these things.

The OP has said that, for whatever reason, he needs to ignore a bad 
server certificate when connecting to HTTPS. Python is a language where 
developers are allowed to shoot themselves in the foot, so long as they 
do so in full knowledge of what they're doing.

So, putting aside all the millions of reasons why the OP shouldn't accept 
an invalid certificate, how can he accept an invalid certificate?



-- 
Steven


From nick at craig-wood.com  Tue Jul 28 08:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Tue, 28 Jul 2009 07:29:56 -0500
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<slrnh6t7lt.o4a.nick@irishsea.home.craig-wood.com>
	<c2d97820-1168-4a1d-9abc-958f073d607f@o15g2000yqm.googlegroups.com>
Message-ID: <slrnh6tpga.rn2.nick@irishsea.home.craig-wood.com>

jakecjacobson <jakecjacobson at gmail.com> wrote:
> > > ?If I go to this server in my browser, I get a "This server tried to
> > > ?identify itself with invalid information". ?Is there a way to
> > > ?ignore this issue with Python? ?Can I setup a trust store and add
> > > ?this server to the trust store?
> >
> > Invalid how? ?Self signed certificate? Domain mismatch? Expired
> > certificate?
>
>  For everyone that wants to discuss why we shouldn't do this, great but
>  I can't change the fact that I need to do this.  I can't use http or
>  even get a correct cert at this time.  This is a quick a dirty project
>  to demonstrate capability.  I need something more than slide show
>  briefs.

I wasn't making a value judgement - I was trying to help!  If you can
get a bit more information out of the browser as to why the
certificate is invalid it may help your python code.

Real certificates cost real money.  Usually a correctly set up
self-signed certificate is fine for dev stuff.  I'm certainly too
cheap to by real certificates for dev or internal stuff!

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From magobin at gmail.com  Tue Jul 28 08:50:35 2009
From: magobin at gmail.com (Alex)
Date: Tue, 28 Jul 2009 05:50:35 -0700 (PDT)
Subject: index nested lists
Message-ID: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>

hi at all,
 If I have this list:

>>> lista
['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]

if I want enumerate elements...I can see:

>>> for parola in lista:
	print lista[i]
	i = i + 1

ciao
1
['mela', 'pera', 'banana']
[1, 2, 3]
>>>

but, if I want to enumerate elements about nested lists ??, something
like:

ciao
1
mela
pera
banana
1
2
3

...How can I do ??

Alex


From dudekksoft at gmail.com  Tue Jul 28 08:54:26 2009
From: dudekksoft at gmail.com (redhot)
Date: Tue, 28 Jul 2009 05:54:26 -0700 (PDT)
Subject: File and TagPy
Message-ID: <11a3ce55-6ba5-4438-9b05-490686e258e6@k1g2000yqf.googlegroups.com>

Hello,
I have question, is it possible to read tag in tagpy module from file
stream?
For example I have earlier read file:
file = open('some.mp3', 'rb')

and next get tags from it?

Regards,
Konrad


From bakes at ymail.com  Tue Jul 28 08:59:02 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 05:59:02 -0700 (PDT)
Subject: FTP Offset larger than file.
Message-ID: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>

I am writing a python script that performs an identical function to
the 'tail' unix utility, except that it connects to its files over
FTP, rather than the local hard disk.

I am currently using this python script to generate an increasing
'logfile' of garbage.

> import time
> for i in range(1, 20000):
>	time.sleep(0.2)
>	print i
>	f = open("data1.log","a")
>	f.write('%s: This logfile is being automatically generated to help Bakes test his python ftptail. \n' % i)
>	f.close()

and use this script to actually download it.

>import time
>import os.path
>from ftplib import FTP
>
>#Empty the file
>filename = 'data1.log'
>file = open(filename, 'w')
>file.write('')
>file.close()
>
>def handleDownload(block):
>    file.write(block)
>    print ".",
>
># Create an instance of the FTP object
># Optionally, you could specify username and password:
>ftp=FTP(host, user, pass)
>
>directory = '/temp'
>ftp.cwd(directory)
>
>file = open(filename, 'a')
>
>for i in range(1,20000):
>  size=os.path.getsize('data1.log')
>  ftp.retrbinary('RETR ' + filename, handleDownload, rest=size)
>
>file.close()
>
>print ftp.close()

Now, my problem is that I get a very strange error. What should be
happening is the script gets the size of the local file before
downloading all of the external file after that offset.

The error I get is:
ftplib.error_temp: 451-Restart offset 24576 is too large for file size
22852.
451 Restart offset reset to 0
which tells me that the local file is larger than the external file,
by about a kilobyte. Certainly, the local file is indeed that size, so
my local script is doing the right things. I do wonder what is going
wrong, can anyone enlighten me?


From npuloski at gmail.com  Tue Jul 28 09:09:18 2009
From: npuloski at gmail.com (Nanime Puloski)
Date: Tue, 28 Jul 2009 09:09:18 -0400
Subject: Internal Math Library of Numpy
Message-ID: <d785f9cc0907280609w2e8d7cddgbf8b3850518e28bc@mail.gmail.com>

Does Numpy use Python's standard math library when calculating
elementary functions such as exp(x) and acos(x)? Also, what is the
internal library of Numpy and Python's standard math library? Is it
platform independent?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/13797243/attachment.html>

From andreas.tawn at ubisoft.com  Tue Jul 28 09:12:41 2009
From: andreas.tawn at ubisoft.com (Andreas Tawn)
Date: Tue, 28 Jul 2009 15:12:41 +0200
Subject: index nested lists
In-Reply-To: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>
References: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>
Message-ID: <8AEDA5E3386EA742B8C24C95FF0C758007B66A65@PDC-MAIL3.ubisoft.org>

> hi at all,
>  If I have this list:
> 
> >>> lista
> ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
> 
> if I want enumerate elements...I can see:
> 
> >>> for parola in lista:
> 	print lista[i]
> 	i = i + 1
> 
> ciao
> 1
> ['mela', 'pera', 'banana']
> [1, 2, 3]
> >>>
> 
> but, if I want to enumerate elements about nested lists ??, something
> like:
> 
> ciao
> 1
> mela
> pera
> banana
> 1
> 2
> 3
> 
> ...How can I do ??
> 
> Alex
> --
> http://mail.python.org/mailman/listinfo/python-list

You could do something like this.

def printNestedList(lst):
    if isinstance(lst, list):
        for element in lst:
            printNestedList(element)
    else:
        print lst

myList = ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
printNestedList(myList)

>>>
ciao
1
mela
pera
banana
1
2
3

Cheers, Drea


From magobin at gmail.com  Tue Jul 28 09:19:03 2009
From: magobin at gmail.com (Alex)
Date: Tue, 28 Jul 2009 06:19:03 -0700 (PDT)
Subject: index nested lists
References: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>
	<mailman.3833.1248786776.8015.python-list@python.org>
Message-ID: <ce51e8e6-bfc7-4b1c-a171-59468eb6ce9b@g31g2000yqc.googlegroups.com>

On 28 Lug, 15:12, "Andreas Tawn" <andreas.t... at ubisoft.com> wrote:
> > hi at all,
> > ?If I have this list:
>
> > >>> lista
> > ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
>
> > if I want enumerate elements...I can see:
>
> > >>> for parola in lista:
> > ? ?print lista[i]
> > ? ?i = i + 1
>
> > ciao
> > 1
> > ['mela', 'pera', 'banana']
> > [1, 2, 3]
>
> > but, if I want to enumerate elements about nested lists ??, something
> > like:
>
> > ciao
> > 1
> > mela
> > pera
> > banana
> > 1
> > 2
> > 3
>
> > ...How can I do ??
>
> > Alex
> > --
> >http://mail.python.org/mailman/listinfo/python-list
>
> You could do something like this.
>
> def printNestedList(lst):
> ? ? if isinstance(lst, list):
> ? ? ? ? for element in lst:
> ? ? ? ? ? ? printNestedList(element)
> ? ? else:
> ? ? ? ? print lst
>
> myList = ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
> printNestedList(myList)
>


thanks a lot !

Alex


From michele.petrazzo at REMOVE_me_unipex.it  Tue Jul 28 09:30:49 2009
From: michele.petrazzo at REMOVE_me_unipex.it (Michele Petrazzo)
Date: Tue, 28 Jul 2009 15:30:49 +0200
Subject: python 3 and stringio.seek
Message-ID: <h4mui9$q1o$1@nnrp-beta.newsland.it>

Hi list,
I'm trying to port a my library to python 3, but I have a problem with a
the stringio.seek:
the method not accept anymore a value like pos=-6 mode=1, but the "old"
(2.X) version yes...

The error:
   File "/home/devel/Py3/lib/python3.0/io.py", line 2031, in seek
     return self._seek(pos, whence)
IOError: Can't do nonzero cur-relative seeks


How solve this?

Thanks,
MIchele


From nobody at nowhere.com  Tue Jul 28 09:31:56 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 28 Jul 2009 14:31:56 +0100
Subject: Gracefully exiting CLI application
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
Message-ID: <pan.2009.07.28.13.31.56.265000@nowhere.com>

On Mon, 27 Jul 2009 22:35:01 +0200, David wrote:

> I am writing a command line application, and I need to perform some
> cleaning on exit even if the process is killed. How can I do that with
> python?

Killed by what means?

Ctrl-C sends SIGINT which is converted to a KeyboardInterrupt exception.
This can be caught, or if it's allowed to terminate the process, any exit
handlers registered via atexit.register() will be used.

For other signals, you can install a handler with signal.signal(). This
can call sys.exit() or raise an exception (e.g. KeyboardInterrupt).

OTOH, if the process is terminated by SIGKILL, there's nothing you can do
about it. And although it's possible to trap SIGSEGV, you shouldn't assume
that the Python interpreter is still functional at this point.



From jeanmichel at sequans.com  Tue Jul 28 09:39:56 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 28 Jul 2009 15:39:56 +0200
Subject: index nested lists
In-Reply-To: <ce51e8e6-bfc7-4b1c-a171-59468eb6ce9b@g31g2000yqc.googlegroups.com>
References: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>	<mailman.3833.1248786776.8015.python-list@python.org>
	<ce51e8e6-bfc7-4b1c-a171-59468eb6ce9b@g31g2000yqc.googlegroups.com>
Message-ID: <4A6EFFAC.30106@sequans.com>

Alex wrote:
> On 28 Lug, 15:12, "Andreas Tawn" <andreas.t... at ubisoft.com> wrote:
>   
>>> hi at all,
>>>  If I have this list:
>>>       
>>>>>> lista
>>>>>>             
>>> ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
>>>       
>>> if I want enumerate elements...I can see:
>>>       
>>>>>> for parola in lista:
>>>>>>             
>>>    print lista[i]
>>>    i = i + 1
>>>       
>>> ciao
>>> 1
>>> ['mela', 'pera', 'banana']
>>> [1, 2, 3]
>>>       
>>> but, if I want to enumerate elements about nested lists ??, something
>>> like:
>>>       
>>> ciao
>>> 1
>>> mela
>>> pera
>>> banana
>>> 1
>>> 2
>>> 3
>>>       
>>> ...How can I do ??
>>>       
>>> Alex
>>> --
>>> http://mail.python.org/mailman/listinfo/python-list
>>>       
>> You could do something like this.
>>
>> def printNestedList(lst):
>>     if isinstance(lst, list):
>>         for element in lst:
>>             printNestedList(element)
>>     else:
>>         print lst
>>
>> myList = ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
>> printNestedList(myList)
>>
>>     
>
>
> thanks a lot !
>
> Alex
>   
One hidden suggestion in Andreas answer is to write your code in 
english, if you can :o)

JM


From exarkun at divmod.com  Tue Jul 28 09:48:02 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Tue, 28 Jul 2009 09:48:02 -0400
Subject: bad certificate error
In-Reply-To: <c2d97820-1168-4a1d-9abc-958f073d607f@o15g2000yqm.googlegroups.com>
Message-ID: <20090728134802.11822.1316828413.divmod.quotient.0@henry.divmod.com>

On Tue, 28 Jul 2009 03:35:55 -0700 (PDT), jakecjacobson <jakecjacobson at gmail.com> wrote:
> [snip]
>
>"Invalid how?  Self signed certificate? Domain mismatch? Expired
>certificate?"  It is a server name mismatch.

Python 2.4 is not capable of allowing you to customize this verification
behavior.  It is hard coded to let OpenSSL make the decision about whether
to accept the certificate or not.

Either M2Crypto or pyOpenSSL will let you ignore verification errors.  The
new ssl module in Python 2.6 may also as well.

Jean-Paul


From jakecjacobson at gmail.com  Tue Jul 28 09:52:37 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Tue, 28 Jul 2009 06:52:37 -0700 (PDT)
Subject: bad certificate error
References: <mailman.3835.1248788885.8015.python-list@python.org>
Message-ID: <332a5bba-48d5-4c8b-9c1e-288790d85dbb@o32g2000yqm.googlegroups.com>

On Jul 28, 9:48?am, Jean-Paul Calderone <exar... at divmod.com> wrote:
> On Tue, 28 Jul 2009 03:35:55 -0700 (PDT), jakecjacobson <jakecjacob... at gmail.com> wrote:
> > [snip]
>
> >"Invalid how? ?Self signed certificate? Domain mismatch? Expired
> >certificate?" ?It is a server name mismatch.
>
> Python 2.4 is not capable of allowing you to customize this verification
> behavior. ?It is hard coded to let OpenSSL make the decision about whether
> to accept the certificate or not.
>
> Either M2Crypto or pyOpenSSL will let you ignore verification errors. ?The
> new ssl module in Python 2.6 may also as well.
>
> Jean-Paul

Thanks, I will look into these suggestions.


From li.weidong at gmail.com  Tue Jul 28 09:54:21 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 06:54:21 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
Message-ID: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>

I am trying to build python 2.6.2 from the source by following the
instructions in README that comes with the source.  The configure and
make steps are fine, but there is an error in "make install" step.
This "make install" attempts to build a lot of lib, and it complains
about the lack of "unicodedata" shared object,

I looked at the source tree and the build result, unicodedata.so does
not exist.  I further notice that in Modules/Setup.dist, the line for
unicodedata.c is commented out by default.  So I uncomment it, and
experiment with rebuilding everything.

This time, with or without re-configure, the "make" step failed with a
link-time error when linking for libpython2.6.a due to "undefined
reference to 'initunicodedata'.  This symbol is defined in
unicodedata.c, but unicodedata.o is not used in linking for
libpython2.6.a, hence the error.  So this is a problem in the
generated Makefile.

Does anyone know what special things I have to do to avoid such
error?  Is there any known problems in the configure/make files in the
python 2.6.2 source code that require special patch?

Is unicodedata.c really needed in python 2.6.2?  If it is needed, why
it is commented out by default in Modules/Setup.dist?  If it is not
needed, why "make install" attempts to use it in compiling the
libraries?  Why those libraries are not designed to be compiled in the
make step, but in the install step?

Thanks for your help!

- Weidong




From li.weidong at gmail.com  Tue Jul 28 09:56:15 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 06:56:15 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
Message-ID: <01581b5a-3ddc-4ed8-abf4-ad41a542812c@l35g2000vba.googlegroups.com>

On Jul 28, 9:54?am, Weidong <li.weid... at gmail.com> wrote:
> I am trying to build python 2.6.2 from the source by following the
> instructions in README that comes with the source. ?The configure and
> make steps are fine, but there is an error in "make install" step.
> This "make install" attempts to build a lot of lib, and it complains
> about the lack of "unicodedata" shared object,
>
> I looked at the source tree and the build result, unicodedata.so does
> not exist. ?I further notice that in Modules/Setup.dist, the line for
> unicodedata.c is commented out by default. ?So I uncomment it, and
> experiment with rebuilding everything.
>
> This time, with or without re-configure, the "make" step failed with a
> link-time error when linking for libpython2.6.a due to "undefined
> reference to 'initunicodedata'. ?This symbol is defined in
> unicodedata.c, but unicodedata.o is not used in linking for
> libpython2.6.a, hence the error. ?So this is a problem in the
> generated Makefile.
>
> Does anyone know what special things I have to do to avoid such
> error? ?Is there any known problems in the configure/make files in the
> python 2.6.2 source code that require special patch?
>
> Is unicodedata.c really needed in python 2.6.2? ?If it is needed, why
> it is commented out by default in Modules/Setup.dist? ?If it is not
> needed, why "make install" attempts to use it in compiling the
> libraries? ?Why those libraries are not designed to be compiled in the
> make step, but in the install step?
>
> Thanks for your help!
>
> - Weidong

To add some info: This experiment was done on Linux, Ubuntu 8.x.


From hniksic at xemacs.org  Tue Jul 28 10:01:52 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 28 Jul 2009 16:01:52 +0200
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
Message-ID: <87ljm8vrcf.fsf@busola.homelinux.net>

Bakes <bakes at ymail.com> writes:

> The error I get is:
> ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> 22852.
> 451 Restart offset reset to 0
> which tells me that the local file is larger than the external file,
> by about a kilobyte. Certainly, the local file is indeed that size, so
> my local script is doing the right things. I do wonder what is going
> wrong, can anyone enlighten me?

I'd say you failed to take buffering into account.  You write into a
buffered file, yet you use os.path.getsize() to find out the current
file size.  If the data is not yet flushed, you keep re-reading the same
stuff from the remote file, and writing it out.  Once the buffer is
flushed, your file will contain more data than was retrieved from the
remote side, and eventually this will result in the error you see.

As a quick fix, you can add a file.flush() line after the
file.write(...) line, and the problem should go away.


From python-url at phaseit.net  Tue Jul 28 10:07:28 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Tue, 28 Jul 2009 14:07:28 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul 28)
Message-ID: <h4n0n0$7ob$1@lairds.us>

QOTW:  "But there's another principle at work here that's less well known, and
that was first articulated to me by Robert Dewar: You can remove linear
factors by profiling, but it's much harder to undo bad algorithmic decisions. 
In particular, whether a program runs in O(n) or O(n^2) sometimes depends on
decisions that have to be frozen fairly early in the design." - Andrew Koenig

    
    Comparing the performance of the same algorithm using many compilers:
    CPython, psyco, Cython, ShedSkin, Unladen Swallow, Java, C and D:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8d793c46903cc0b6/
    
    MRAB has written a new implementation of re module with many new
    features, and he's looking for feedback:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/16c139b0a52ab023/
    
    Importing two modules with the same name from different directories:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3cb83a30e1b2c202/
    
    Cleanly exiting an application, even if it gets killed by a signal:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/d60b8e0d93aeaaf9/
    
    How can a child thread notify a parent thread of its status?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/d1d7f55716aacedc/
    
    How to attach a docstring to global constants/variables?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/ac54186ad873036a/
    
    In Python -unlike other languages- it does not make sense to treat
    numbers (scalars) as vectors of length 1:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3ef498c906bd7e2d/
    
    isinstance may take a tuple of types as its second argument: why a
    tuple, and not a list, or a set?
        http://mail.python.org/pipermail/python-list/2009-July/721205.html
    
    How to overcome the normal 2GB allocation limit of Windows XP, 32bits:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/59851df6e54f9ef0/
    
    Distinguishing active generators from exhausted ones:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/9ff179e8cb5e9bc/
    
    Peter Otten must be, undoubtedly, Sherlock Holmes reincarnated:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/838177c8a37d2b7c/
    
    And Piet van Oostrum is not much behind him:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/d1f8627413cd3c4e/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From lists at cheimes.de  Tue Jul 28 10:17:20 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 28 Jul 2009 16:17:20 +0200
Subject: Questions about unicodedata in python 2.6.2
In-Reply-To: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
Message-ID: <h4n19g$l3p$1@ger.gmane.org>

Weidong schrieb:
> I am trying to build python 2.6.2 from the source by following the
> instructions in README that comes with the source.  The configure and
> make steps are fine, but there is an error in "make install" step.
> This "make install" attempts to build a lot of lib, and it complains
> about the lack of "unicodedata" shared object,

unicodedata is usually build as a shared library and not linked into the
Python core. How did you configure Python? The usual prodecure is:

   ./configure
   make
   sudo make install

On Unix the preferred option for ./configure is "--enable-unicode=ucs4".

Christian



From gdamjan at gmail.com  Tue Jul 28 10:17:45 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Tue, 28 Jul 2009 16:17:45 +0200
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>
Message-ID: <9td3k6-eid.ln1@archaeopteryx.softver.org.mk>

> So do all these OSes have some kind of __mega_unifying_poll system
> call that works for anything that might possibly block, that you can
> exploit from a user process?

On Linux at least, the select/poll/epoll is that system, the trick is to 
use eventfd, timerfd and signalfd which are Linux specific system calls.

I think that covers everything needed. (eventfd is used for semaphores)


-- 
?????? ( http://softver.org.mk/damjan/ )

Give me the knowledge to change the code I do not accept, 
the wisdom not to accept the code I cannot change, 
and the freedom to choose my preference.



From bakes at ymail.com  Tue Jul 28 10:18:48 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 07:18:48 -0700 (PDT)
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
Message-ID: <bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>

On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
> Bakes <ba... at ymail.com> writes:
> > The error I get is:
> > ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> > 22852.
> > 451 Restart offset reset to 0
> > which tells me that the local file is larger than the external file,
> > by about a kilobyte. Certainly, the local file is indeed that size, so
> > my local script is doing the right things. I do wonder what is going
> > wrong, can anyone enlighten me?
>
> I'd say you failed to take buffering into account. ?You write into a
> buffered file, yet you use os.path.getsize() to find out the current
> file size. ?If the data is not yet flushed, you keep re-reading the same
> stuff from the remote file, and writing it out. ?Once the buffer is
> flushed, your file will contain more data than was retrieved from the
> remote side, and eventually this will result in the error you see.
>
> As a quick fix, you can add a file.flush() line after the
> file.write(...) line, and the problem should go away.

Thank you very much, that worked perfectly.


From bakes at ymail.com  Tue Jul 28 10:33:05 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 07:33:05 -0700 (PDT)
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
Message-ID: <fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>

On 28 July, 15:18, Bakes <ba... at ymail.com> wrote:
> On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
>
>
>
> > Bakes <ba... at ymail.com> writes:
> > > The error I get is:
> > > ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> > > 22852.
> > > 451 Restart offset reset to 0
> > > which tells me that the local file is larger than the external file,
> > > by about a kilobyte. Certainly, the local file is indeed that size, so
> > > my local script is doing the right things. I do wonder what is going
> > > wrong, can anyone enlighten me?
>
> > I'd say you failed to take buffering into account. ?You write into a
> > buffered file, yet you use os.path.getsize() to find out the current
> > file size. ?If the data is not yet flushed, you keep re-reading the same
> > stuff from the remote file, and writing it out. ?Once the buffer is
> > flushed, your file will contain more data than was retrieved from the
> > remote side, and eventually this will result in the error you see.
>
> > As a quick fix, you can add a file.flush() line after the
> > file.write(...) line, and the problem should go away.
>
> Thank you very much, that worked perfectly.

Actually, no it didn't. That fix works seamlessly in Linux, but gave
the same error in a Windows environment. Is that expected?


From stef.mientki at gmail.com  Tue Jul 28 10:35:39 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Tue, 28 Jul 2009 16:35:39 +0200
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>	<4A6DC0FC.90704@stoneleaf.us>	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>
	<mailman.3784.1248709156.8015.python-list@python.org>
	<b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>
Message-ID: <4A6F0CBB.8050609@gmail.com>


> Matlab, from The Mathworks, has a companion product called Simulink.
> This allows the user to graphically build ?algorithms? in block form.
> There is a similar Python function.
>   
Where can I find a Python functionality like simulink  ?

thanks,
Stef Mientki





From cournape at gmail.com  Tue Jul 28 10:37:22 2009
From: cournape at gmail.com (David Cournapeau)
Date: Tue, 28 Jul 2009 23:37:22 +0900
Subject: Internal Math Library of Numpy
In-Reply-To: <d785f9cc0907280609w2e8d7cddgbf8b3850518e28bc@mail.gmail.com>
References: <d785f9cc0907280609w2e8d7cddgbf8b3850518e28bc@mail.gmail.com>
Message-ID: <5b8d13220907280737k43d2fad1k479f597e062176d2@mail.gmail.com>

On Tue, Jul 28, 2009 at 10:09 PM, Nanime Puloski<npuloski at gmail.com> wrote:
> Does Numpy use Python's standard math library when calculating
> elementary functions such as exp(x) and acos(x)?

It depends on the dtype: for fundamental types (float, int, etc...),
the underlying implementation is whatever the (C) math library
provides. If the functionality is not there, we have our own custom
implementation (but exp and acos happen to be mandatory - if they are
not detected, the build fail).

> Also, what is the
> internal library of Numpy and Python's standard math library? Is it
> platform independent?

I don't know for python, but for numpy, we have our own math library
on top of whatever the platform provides (which is not much on
windows, for example). There is an ongoing effort in numpy to provides
a portable, pure C (independent of the python runtime) math library.
The goal is to have a portable C99 math library, and more later
hopefully.

cheers,

David


From woakas at gfc.edu.co  Tue Jul 28 10:50:27 2009
From: woakas at gfc.edu.co (Gustavo =?iso-8859-1?Q?Andr=E9s?= Angulo)
Date: Tue, 28 Jul 2009 09:50:27 -0500
Subject: WSDL and XML generation
In-Reply-To: <3be39c48-6a89-4542-b08a-eaf00933b184@c1g2000yqi.googlegroups.com>
References: <3be39c48-6a89-4542-b08a-eaf00933b184@c1g2000yqi.googlegroups.com>
Message-ID: <20090728145027.GA11013@gfc.edu.co>

Hi you can generate the WSDl with soaplib [1], and you can view web.py or django
for this: 

for web.py -> http://webpy.org/cookbook/webservice

for django -> http://www.djangosnippets.org/snippets/979/


[1]=> http://trac.optio.webfactional.com/

> Hi all
> Newbie in Python, i am looking for some pointers (or better existing
> modules) to do the followings:
> 
> - generate (correct) XML messages from a WSDL file
> - make some modifications inside XML messages *before* sending them to
> the server hosting the Web services (described by previously
> mentionned WSDL file)
> - parse the answer.
> 
> Some ideas ?
> Thanks in advance
> Stephane
> -- 
> http://mail.python.org/mailman/listinfo/python-list
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/8205e2fb/attachment.sig>

From python at mrabarnett.plus.com  Tue Jul 28 10:59:06 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 15:59:06 +0100
Subject: New implementation of re module
In-Reply-To: <h4lp5a$ehd$1@panix3.panix.com>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<h4lp5a$ehd$1@panix3.panix.com>
Message-ID: <4A6F123A.7030002@mrabarnett.plus.com>

Aahz wrote:
> In article <mailman.3787.1248712420.8015.python-list at python.org>,
> MRAB  <python at mrabarnett.plus.com> wrote:
>> I've been working on a new implementation of the re module. The details
>> are at http://bugs.python.org/issue2636, specifically from
>> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>> Python 2.6 on Windows if you want to try it out.
> 
> How does it handle the re module's unit tests?

Basically, it passes all those tests I expect it to pass. :-)

It fails those where the intended behaviour has changed, such as re.sub
treating unmatched groups as empty strings, as requested in
http://bugs.python.org/issue1519638.


From python at mrabarnett.plus.com  Tue Jul 28 11:11:02 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 16:11:02 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <200907281035.48713.hendrik@microcorp.co.za>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<mailman.3765.1248685391.8015.python-list@python.org>	<h4kepl$qhf$1@panix3.panix.com>
	<200907281035.48713.hendrik@microcorp.co.za>
Message-ID: <4A6F1506.9030207@mrabarnett.plus.com>

Hendrik van Rooyen wrote:
> On Monday 27 July 2009 16:49:25 Aahz wrote:
>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>
>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>> I have searched, but I can find nothing about this mediocre language.
>>>
>>> Could you tell us more?
>>>
>> :-P
>>
>> (For anyone who is confused by Hendrik's humor, he is saying that David
>> was referring to a programming language named "mediocre".  English
>> grammar is confusing!)
> 
> This is true - I intended, when I started the post, to make a crack about
> how he knew that he was mediocre - If there were some exam or test
> that you have to pass or fail to be able to make the claim to mediocrity.
> I was imagining a sort of devil's rating scale for programmers, that
> could cause one to say things like:  "I am studying hard so that I can
> get my mediocre certificate, and one day I hope to reach hacker rank".
> 
> And then the similarity to "I am a COBOL programmer" struck me, 
> and I abandoned the ratings.
> 
If you were a "COBOL" programmer, would you want to shout about it? :-)


From phillip.oldham at gmail.com  Tue Jul 28 11:15:49 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Tue, 28 Jul 2009 08:15:49 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com> 
	<123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com> 
	<7xws60u06g.fsf@ruckus.brouhaha.com>
	<83889f6f-1e40-435e-b947-af17964e90af@d32g2000yqh.googlegroups.com>
Message-ID: <62d0b6e4-5356-4b53-b08b-9c99933d2c0f@s31g2000yqs.googlegroups.com>

In answer to my own question, I came across Octo.py[1] today. Not
tested/played-with/used it yet, however, though it seems simple
enough.

Still welcoming any suggestions for other/similar tools.

[1] http://code.google.com/p/octopy/


From dearmanzur at gmail.com  Tue Jul 28 11:17:25 2009
From: dearmanzur at gmail.com (Manzur Ahmed)
Date: Tue, 28 Jul 2009 11:17:25 -0400
Subject: need help using Tkinter
Message-ID: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>

i wanted to ask you if one of you could help me to use Tkinter. i'm trying
to just create a simple GUI for which I have provided the code for below.

# Simple GUI
# Demonstrates creating a window

from Tkinter import *

# create the root window
root = Tk ()

# modify the window
root.title("Simple GUI")
root.geometry("200x100")

# kick off the window's event loop
root.mainloop()

i saved the file as both simple_gui.py and simple_gui.pyw. when i try to run
simple_gui.pyw i don't get anything and when i try to run simple_gui.py i
get the following:
Traceback (most recent call last):
File "C:\Python-Study\Chapter10\simple_gui.py", line 4, in <module>
ImportError: No module named Tkinter

i tried to google search this and there were some threads that were saying
to install tcl but that does not work. I did check the Lib directory under
the Python directory and I did not see a Tkinter module anywhere which I
think is the problem. Do you know how I would go about with getting this
module and if that is not the problem or if you think it might be caused by
something else, can you please give me some guidance? i even reinstalled
python 3.1 which i got from www.python.org.  i still do not see the Tkinter
module in the lib directory.  thank you for all your help.

manzur
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/f14cc879/attachment.html>

From hniksic at xemacs.org  Tue Jul 28 11:22:38 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 28 Jul 2009 17:22:38 +0200
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
	<fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>
Message-ID: <873a8gg7cx.fsf@busola.homelinux.net>

Bakes <bakes at ymail.com> writes:

>> > As a quick fix, you can add a file.flush() line after the
>> > file.write(...) line, and the problem should go away.
>>
>> Thank you very much, that worked perfectly.
>
> Actually, no it didn't. That fix works seamlessly in Linux, but gave
> the same error in a Windows environment. Is that expected?

Consider opening the file in binary mode, by passing the 'wb' and 'ab'
modes to open instead of 'w' and 'a' respectively.  On Windows, python
(and other languages) will convert '\n' to '\r\n' on write.


From python at mrabarnett.plus.com  Tue Jul 28 11:32:45 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 16:32:45 +0100
Subject: need help using Tkinter
In-Reply-To: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
Message-ID: <4A6F1A1D.7090604@mrabarnett.plus.com>

Manzur Ahmed wrote:
> i wanted to ask you if one of you could help me to use Tkinter. i'm 
> trying to just create a simple GUI for which I have provided the code 
> for below.
> 
> # Simple GUI
> # Demonstrates creating a window
> 
> from Tkinter import *
> 
> # create the root window
> root = Tk ()
> 
> # modify the window
> root.title("Simple GUI")
> root.geometry("200x100")
> 
> # kick off the window's event loop
> root.mainloop()
> 
> i saved the file as both simple_gui.py and simple_gui.pyw. when i try to 
> run simple_gui.pyw i don't get anything and when i try to run 
> simple_gui.py i get the following:
> Traceback (most recent call last):
> File "C:\Python-Study\Chapter10\simple_gui.py", line 4, in <module>
> ImportError: No module named Tkinter
> 
> i tried to google search this and there were some threads that were 
> saying to install tcl but that does not work. I did check the Lib 
> directory under the Python directory and I did not see a Tkinter module 
> anywhere which I think is the problem. Do you know how I would go about 
> with getting this module and if that is not the problem or if you think 
> it might be caused by something else, can you please give me some 
> guidance? i even reinstalled python 3.1 which i got from www.python.org 
> <http://www.python.org/>.  i still do not see the Tkinter module in the 
> lib directory.  thank you for all your help.
> 
There are some differences between Python 3.x and Python 2.x. In Python
3.1 the module is called "tkinter", not "Tkinter" (names are
case-sensitive).


From nagle at animats.com  Tue Jul 28 12:02:29 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 28 Jul 2009 09:02:29 -0700
Subject: M2Crypto hangs on this URL
In-Reply-To: <fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
	<4a6e0c53$0$1644$742ec2ed@news.sonic.net>
	<fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>
Message-ID: <4a6f2067$0$1649$742ec2ed@news.sonic.net>

Martin P. Hellwig wrote:
> John Nagle wrote:
>> John Nagle wrote:
>>> John Nagle wrote:
>>>> There's something strange about this URL:
>>>>
>>>> "https://sagar310.pontins.com/sraep/"
...
> It looks to me like the SSL handshake is not done properly from the 
> server side.
> 
> Compare the output of:
> openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts 
> -msg
> 
> With (for example):
> openssl s_client -host www.google.com -port 443 -debug -showcerts -msg

   OpenSSL is clearly not happy with that site.  But it doesn't hang.

openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts  -msg

eventually prints

"Verify return code: 19 (self signed certificate in certificate chain)"
That's weird, because there's a Verisign certificate in the chain.
That site is somehow mishandling its certs.

My problem, though, is that M2Crypto 0.17 is hanging for hours to days
on those connections.

					John Nagle


From li.weidong at gmail.com  Tue Jul 28 12:16:57 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 09:16:57 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
	<mailman.3837.1248790649.8015.python-list@python.org>
Message-ID: <1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>

On Jul 28, 10:17?am, Christian Heimes <li... at cheimes.de> wrote:
> unicodedatais usually build as a shared library and not linked into the
> Python core. How did you configure Python? The usual prodecure is:
>
> ? ?./configure
> ? ?make
> ? ?sudo make install
>
> On Unix the preferred option for ./configure is "--enable-unicode=ucs4".
>
> Christian

Thanks for your response!  I configured it in the same way as you
said, but without "--enable-unicode=ucs4".  The ocnfig.log shows that
checking for UCS-4 was failed.  So I assume that by default UCS-2 was
used.  There was no other problme in the "make" step.

The problem was in the "sudo make install" step, where there were
errors in building libraries / test libraries that need unicodedata.so
which did not exist.

I also tried to use "make -i" to let it complete the building to
ignore that error.  In the end, I still did not see unicodedata.so in
the build result.  It seems that the Makefile did not even try to
build unicodedata.so.

Maybe something went wrong in my configuration?

- Weidong


From rylesny at gmail.com  Tue Jul 28 12:21:39 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 28 Jul 2009 09:21:39 -0700 (PDT)
Subject: Wrapping prstat on Solaris
References: <mailman.3776.1248704814.8015.python-list@python.org>
Message-ID: <1bce2ffd-85cb-4860-8b3e-92d8e1619a46@k19g2000yqn.googlegroups.com>

On Jul 27, 10:26?am, s... at pobox.com wrote:
> At work we currently use top to monitor ongoing system utilization on our
> Solaris systems. ?As time has moved on though, use of top has become
> problematic. ?Our admins want us to switch to prstat, Sun's top-like
> command. ?It works fine however doesn't emit a timestamp at each display
> interval, so it's essentially impossible looking at a prstat output
> file to determine when the particular "screen" was emitted.
>
> If figured, "No problem. ?I'll just write a little wrapper." ?Alas, that is
> proving harder than I thought. ?I can run prstat directing output to a file
> and it seems to blast out a block of lines every N seconds, but when run
> from inside a Python script I can't seem to make the damn thing not
> massively buffer its output. ?Accordingly, my script doesn't really see the
> output as its emitted, so the timestamp line it prepends to a block of
> output is off.
>
> I'm currently using subprocess.Popen like so:
>
> ? ? os.environ["TERM"] = "dumb"
> ? ? cmd = "prstat -c %s" % " ".join(sys.argv[1:])
> ? ? pipe = Popen(cmd, shell=True, bufsize=1, stdout=PIPE).stdout
>
> I've tried these other variants as well:
>
> ? * prefacing the prstat command with unbuffer (the tcl/expect thingamabob)
>
> ? * explicitly redirect the prstat output to /dev/stdout
>
> ? * setting bufsize to 0
>
> ? * used os.popen instead of Subprocess.Popen
>
> Nothing seems to help. ?I always seem to see about 30 seconds of data at
> once (I'm currently using a 5-second interval and 10 lines of output). ?I
> would have expected that prstat would simply flush stdout after each block
> of output.
>
> Any ideas about how to get prstat to cooperate better?
>
> Thanks,
>
> --
> Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> ? ? That's more than a dress. That's an Audrey Hepburn movie. -- Jerry Maguire

Hey Skip,

You haven't told us how you are actually reading from prstat's output
pipe, which may be the cause. For instance, if you are doing

for line in pipe:
  print line
  ...

then this could cause your buffering issue.

Instead try using readline():

while True:
  line = pipe.readline()
  ...


From daniel.harjanto at gmail.com  Tue Jul 28 12:30:26 2009
From: daniel.harjanto at gmail.com (misterdi)
Date: Tue, 28 Jul 2009 09:30:26 -0700 (PDT)
Subject: Python as active script <script language=python>
Message-ID: <862eed23-2aea-4e9f-977a-6afd0bfa24a3@x25g2000prf.googlegroups.com>

I'm using Activestate python,
For older version of python, I know that we can register python as
active script by registering it through win32comext.axscript.client
pyscript.py
And to do that I need to change something in this pyscript.py before
running pyscript_rexec.py(http://fastq.com/~sckitching/Python/
win32_activeX_pyscript.htm),
but I can't find similar thing with python 2.6.2

I can't find the line that need to be changed.

Can someone kindly show me how to enable python26 as an active script
for IE?

Thanks,


From rylesny at gmail.com  Tue Jul 28 12:31:28 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 28 Jul 2009 09:31:28 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com> 
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com> 
	<m2my6p9mj5.fsf@cs.uu.nl> <87prblul0l.fsf@busola.homelinux.net> 
	<c8ff2ba2-b62b-40e8-ae7e-b78cac491812@s31g2000yqs.googlegroups.com>
Message-ID: <feb4e6af-39a3-42a2-9b12-63e986408559@d4g2000yqa.googlegroups.com>

On Jul 28, 7:55?am, NiklasRTZ <nikla... at gmail.com> wrote:

> Sincere thanks for strengthening python's superior flexibility. Same
> function also works around an exploding index problem returning
> results for longest word where otherwise a word with whitespace
> crashes the index:

Babelfish?



From davea at ieee.org  Tue Jul 28 12:36:56 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 28 Jul 2009 12:36:56 -0400
Subject: FTP Offset larger than file.
In-Reply-To: <fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>	<87ljm8vrcf.fsf@busola.homelinux.net>	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
	<fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>
Message-ID: <4A6F2928.5000800@ieee.org>

Bakes wrote:
> On 28 July, 15:18, Bakes <ba... at ymail.com> wrote:
>   
>> On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
>>
>>
>>
>>     
>>> Bakes <ba... at ymail.com> writes:
>>>       
>>>> The error I get is:
>>>> ftplib.error_temp: 451-Restart offset 24576 is too large for file size
>>>> 22852.
>>>> 451 Restart offset reset to 0
>>>> which tells me that the local file is larger than the external file,
>>>> by about a kilobyte. Certainly, the local file is indeed that size, so
>>>> my local script is doing the right things. I do wonder what is going
>>>> wrong, can anyone enlighten me?
>>>>         
>>> I'd say you failed to take buffering into account.  You write into a
>>> buffered file, yet you use os.path.getsize() to find out the current
>>> file size.  If the data is not yet flushed, you keep re-reading the same
>>> stuff from the remote file, and writing it out.  Once the buffer is
>>> flushed, your file will contain more data than was retrieved from the
>>> remote side, and eventually this will result in the error you see.
>>>       
>>> As a quick fix, you can add a file.flush() line after the
>>> file.write(...) line, and the problem should go away.
>>>       
>> Thank you very much, that worked perfectly.
>>     
>
> Actually, no it didn't. That fix works seamlessly in Linux, but gave
> the same error in a Windows environment. Is that expected?
>
>   
This is a text file you're transferring.  And you didn't specify "wb".  
So the Windows size will be larger than the Unix size, since you're 
expanding the newline characters.

getsize() is looking at the size after newlines are expanded to 0d0a, 
while The remote file, presumably a Unix system likely has just has 0a.

I think you'd do best just keeping track of the bytes you've written.


DaveA


From lists at cheimes.de  Tue Jul 28 12:37:36 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 28 Jul 2009 18:37:36 +0200
Subject: Questions about unicodedata in python 2.6.2
In-Reply-To: <1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>	<mailman.3837.1248790649.8015.python-list@python.org>
	<1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>
Message-ID: <h4n9gh$jrt$1@ger.gmane.org>

Weidong wrote:
> Thanks for your response!  I configured it in the same way as you
> said, but without "--enable-unicode=ucs4".  The ocnfig.log shows that
> checking for UCS-4 was failed.  So I assume that by default UCS-2 was
> used.  There was no other problme in the "make" step.

Correct

> The problem was in the "sudo make install" step, where there were
> errors in building libraries / test libraries that need unicodedata.so
> which did not exist.

'make install' shouldn't compile any libraries if you run 'make' prior
to 'make install'. I suggest you start again with a clean build tree of
Python 2.6.2.

Christian



From chris.arndt at web.de  Tue Jul 28 13:07:26 2009
From: chris.arndt at web.de (Christopher Arndt)
Date: Tue, 28 Jul 2009 10:07:26 -0700 (PDT)
Subject: New implementation of re module
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<mailman.3792.1248722883.8015.python-list@python.org>
Message-ID: <a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>

On 27 Jul., 21:27, Wolfgang Rohdewald <wolfg... at rohdewald.de> wrote:
> how do I compile _regex.c on Linux?

This simple setup.py file should do the trick:

from distutils.core import setup, Extension

setup(name='regex',
    version='1.0',
    py_modules = ['regex'],
    ext_modules=[Extension('_regex', ['_regex.c'])],
)

Also, you need to copy "unicodedata_db.h" from the "Modules" directory
of the Python source tree to your working directory, since this file
apparently is not installed into the include directory of a Python
installation.

I get an error for Python 2.5 on Mac OS X 10.4 and Linux though. Seems
that the module is not compatible with Python 2.5.

_regex.c: In function 'getstring':
_regex.c:2425: error: invalid type argument of '->'
_regex.c: In function 'getstring':
_regex.c:2425: error: invalid type argument of '->'
lipo: can't figure out the architecture type of: /var/tmp//
ccT3oDXD.out
error: command 'gcc' failed with exit status 1

resp. on Linux:

_regex.c: In function 'getstring':
_regex.c:2425: warning: implicit declaration of function 'Py_TYPE'
_regex.c:2425: error: invalid type argument of '->'
_regex.c: In function 'get_match_replacement':
_regex.c:2900: warning: implicit declaration of function
'PyLong_AsSsize_t'
error: command 'gcc' failed with exit status 1

With the official Python 2.6 distribution for Mac OS X it works.

Chris


From python at mrabarnett.plus.com  Tue Jul 28 13:25:43 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 18:25:43 +0100
Subject: New implementation of re module
In-Reply-To: <a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<mailman.3792.1248722883.8015.python-list@python.org>
	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
Message-ID: <4A6F3497.3010602@mrabarnett.plus.com>

Christopher Arndt wrote:
> On 27 Jul., 21:27, Wolfgang Rohdewald <wolfg... at rohdewald.de> wrote:
>> how do I compile _regex.c on Linux?
> 
> This simple setup.py file should do the trick:
> 
> from distutils.core import setup, Extension
> 
> setup(name='regex',
>     version='1.0',
>     py_modules = ['regex'],
>     ext_modules=[Extension('_regex', ['_regex.c'])],
> )
> 
> Also, you need to copy "unicodedata_db.h" from the "Modules" directory
> of the Python source tree to your working directory, since this file
> apparently is not installed into the include directory of a Python
> installation.
> 
> I get an error for Python 2.5 on Mac OS X 10.4 and Linux though. Seems
> that the module is not compatible with Python 2.5.
> 
> _regex.c: In function 'getstring':
> _regex.c:2425: error: invalid type argument of '->'
> _regex.c: In function 'getstring':
> _regex.c:2425: error: invalid type argument of '->'
> lipo: can't figure out the architecture type of: /var/tmp//
> ccT3oDXD.out
> error: command 'gcc' failed with exit status 1
> 
> resp. on Linux:
> 
> _regex.c: In function 'getstring':
> _regex.c:2425: warning: implicit declaration of function 'Py_TYPE'
> _regex.c:2425: error: invalid type argument of '->'
> _regex.c: In function 'get_match_replacement':
> _regex.c:2900: warning: implicit declaration of function
> 'PyLong_AsSsize_t'
> error: command 'gcc' failed with exit status 1
> 
> With the official Python 2.6 distribution for Mac OS X it works.
> 
The source code is intended to replace the current 're' module in Python
2.7 (and I'll be porting it to Python 3.2), so I'm not that worried
about Python versions earlier than 2.6 for testing, although if there's
sufficient need then I could tweak the sources for 2.5.


From lemmath at gmail.com  Tue Jul 28 14:02:16 2009
From: lemmath at gmail.com (Vincent Vega)
Date: Tue, 28 Jul 2009 11:02:16 -0700 (PDT)
Subject: Print value CLOB via cx_Oracle
Message-ID: <6de8842b-f1c6-460e-a705-4f6dbd81492c@a26g2000yqn.googlegroups.com>

Hi,

I call function in Oracle database use cx_Oracle.
In standard I define:

db       = cx_Oracle.connect(username, password, tnsentry)
cursor  = db.cursor()

I create variable 'y' (result function 'fun_name') and call function
'fun_name':

y   = cursor.var(cx_Oracle.CLOB)
cursor.callfunc(fun_name, cx_Oracle.CLOB, y)

When I print variable 'y' I receive:
<cx_Oracle.CLOB with value <cx_Oracle.LOB object at 0x00999999>>

How can I get value variable 'y'???
How read <cx_Oracle.LOB object at 0x00999999>???


Vincent Vega




Note:
Off course y.read() does not work, cause 'y'is CLOB not LOB.
(see datatypes table in site: http://www.oracle.com/technology/pub/articles/prez-python-queries.html)





From martin.hellwig at dcuktec.org  Tue Jul 28 14:21:32 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 28 Jul 2009 19:21:32 +0100
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6f2067$0$1649$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
	<4a6e0c53$0$1644$742ec2ed@news.sonic.net>
	<fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>
	<4a6f2067$0$1649$742ec2ed@news.sonic.net>
Message-ID: <eu-dnRYQS6Qx3PLXnZ2dnUVZ8tRi4p2d@bt.com>

John Nagle wrote:
> Martin P. Hellwig wrote:
>> John Nagle wrote:
>>> John Nagle wrote:
>>>> John Nagle wrote:
>>>>> There's something strange about this URL:
>>>>>
>>>>> "https://sagar310.pontins.com/sraep/"
> ...
>> It looks to me like the SSL handshake is not done properly from the 
>> server side.
>>
>> Compare the output of:
>> openssl s_client -host sagar310.pontins.com -port 443 -debug 
>> -showcerts -msg
>>
>> With (for example):
>> openssl s_client -host www.google.com -port 443 -debug -showcerts -msg
> 
>   OpenSSL is clearly not happy with that site.  But it doesn't hang.
> 
> openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts  
> -msg
> 
> eventually prints
> 
> "Verify return code: 19 (self signed certificate in certificate chain)"
> That's weird, because there's a Verisign certificate in the chain.
> That site is somehow mishandling its certs.
> 
> My problem, though, is that M2Crypto 0.17 is hanging for hours to days
> on those connections.
> 
>                     John Nagle

Well it hanged when I tried it, however the site now does return 
something when using Firefox, so I assume somebody is doing some work 
there or the server decided to do something else.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From varun.cent at gmail.com  Tue Jul 28 14:22:00 2009
From: varun.cent at gmail.com (varun)
Date: Tue, 28 Jul 2009 23:52:00 +0530
Subject: Language detector for Python using en-gram.
Message-ID: <1c7eb5470907281122v4c080c6bm2357173bb3f7e1fd@mail.gmail.com>

One of my friend suggested me to do a language detector for python.At
present the language detector in python is in uni-gram mode and i have
planned to do it in en-gram mode.Kindly give me your suggestion as i am
doing this as my final year project.


With Anticipation,

Varun V. Kumar
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/150df3f9/attachment.html>

From fengmang_python at sina.com  Tue Jul 28 14:41:57 2009
From: fengmang_python at sina.com (fengmang_python at sina.com)
Date: Wed, 29 Jul 2009 02:41:57 +0800 
Subject: C function taking double pointer to a structure variable as OUTPUT
	parameter
Message-ID: <20090728184157.B0F5010C1D53@mail3-11.sinamail.sina.com.cn>

Hi, Everyone,
I am a newbie to both Swig and Python. I am trying to export a set of C APIs to Python. 
My C function is 
int getInfor( char* name, int height, int weight, Infor** infor) //where infor is an OUTPUT parameter
{
......
*infor = (Infor*)malloc(sizeof(Infor));
......
}
&nbsp;
The declare of structure Infor is :
&nbsp;typedef struct {
&nbsp;char&nbsp;&nbsp;name[20];
&nbsp;int&nbsp;&nbsp;&nbsp;height;
&nbsp;int&nbsp;&nbsp;&nbsp;weight;
} Infor
&nbsp;
When wrote the below lines in the interface file named Extest.i
%module Extest
%{
#include "Extest.h"
%}
%typemap(out) Infor **OUTPUT {Infor **c}
%apply int *OUTPUT {int *c}
%include "Extest.h"
&nbsp;
And then, How to write testing python file to call the function named getInfor()?
such as in test.py
&nbsp;
infor = Extest.Infor()
res = Extest.getInfor("Test Name", 175, 80, infor)
&nbsp;
when run upper's test.py, Error occured. The message is 
TypeError: in method 'getInfor', argument 4 of type 'Infor **'
&nbsp;
How to write the test.py to transfer the&nbsp; 'Infor **' type's parameter?
After putting lot of trail and errors, I am writing this mail.
Could you please help me to write the test.py or swig interface file for the above function?
Thank you,
jemmy
Awaiting you
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/11c88104/attachment.html>

From 71david at libero.it  Tue Jul 28 14:44:32 2009
From: 71david at libero.it (David)
Date: Tue, 28 Jul 2009 20:44:32 +0200
Subject: Gracefully exiting CLI application
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
	<pan.2009.07.28.13.31.56.265000@nowhere.com>
Message-ID: <t36oxhy765vj.dpzs2pnx155b.dlg@40tude.net>

Il Tue, 28 Jul 2009 14:31:56 +0100, Nobody ha scritto:

> Killed by what means?
> 
> Ctrl-C sends SIGINT which is converted to a KeyboardInterrupt exception.
> This can be caught, or if it's allowed to terminate the process, any exit
> handlers registered via atexit.register() will be used.
> 
> For other signals, you can install a handler with signal.signal(). This
> can call sys.exit() or raise an exception (e.g. KeyboardInterrupt).
> 
> OTOH, if the process is terminated by SIGKILL, there's nothing you can do
> about it. And although it's possible to trap SIGSEGV, you shouldn't assume
> that the Python interpreter is still functional at this point.

I'm really sorry guys, I forgot to mention that the platform is win32, where
there is minimal support to signals.

Anyway I've found a solution with win32api.SetConsoleCtrlHandler that
installs a event handler which traps all windows events, CTRL_CLOSE_EVENT,
CTRL_LOGOFF_EVENT, and CTRL_SHUTDOWN_EVENT included.

David.


From malkia at mac.com  Tue Jul 28 14:46:38 2009
From: malkia at mac.com (Dimiter "malkia" Stanev)
Date: Tue, 28 Jul 2009 11:46:38 -0700
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>
Message-ID: <h4nh2f$bl5$2@malkia.motzarella.org>

Xah Lee wrote:

> PHP is functional.

PHP is functional, as in "it functions!". PHP is not functional, as in 
"it ain't functions!"


From djames.suhanko at gmail.com  Tue Jul 28 15:27:24 2009
From: djames.suhanko at gmail.com (Djames Suhanko)
Date: Tue, 28 Jul 2009 16:27:24 -0300
Subject: Discovery IP in connection
In-Reply-To: <m2ws5taexq.fsf@cs.uu.nl>
References: <mailman.3797.1248726749.8015.python-list@python.org>
	<m2ws5taexq.fsf@cs.uu.nl>
Message-ID: <fd9e6bba0907281227l604201afx97d79bca5bd91385@mail.gmail.com>

Thanks, all!
 I didn't tried to print addr. :-(
 sorry all. I'm learning python yet.
Thanks again !

On Mon, Jul 27, 2009 at 8:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Djames Suhanko <djames.suhanko at gmail.com> (DS) wrote:
>
>>DS> Hello,all!
>>DS> ?I wrote a little programa that listening UDP packets. A can receive
>>DS> the messages, but I can't see the the origin IP.
>>DS> ?How can I to ?get the remote IP address in connection?
>
> What do you think the addr is for in
> data, addr = mySocket.recvfrom(100)?
>
>>DS> My source:
>
>>DS> #!/usr/bin/env python
>>DS> import socket
>>DS> mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
>>DS> mySocket.bind ( ( '', 514 ) )
>
>>DS> data, addr = mySocket.recvfrom(100)
>>DS> print data
>
> --
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Djames Suhanko
LinuxUser 158.760


From piet at cs.uu.nl  Tue Jul 28 15:44:05 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 21:44:05 +0200
Subject: bad certificate error
References: <mailman.3835.1248788885.8015.python-list@python.org>
	<332a5bba-48d5-4c8b-9c1e-288790d85dbb@o32g2000yqm.googlegroups.com>
Message-ID: <m263dca8ze.fsf@cs.uu.nl>

>>>>> jakecjacobson <jakecjacobson at gmail.com> (j) wrote:

>j> On Jul 28, 9:48?am, Jean-Paul Calderone <exar... at divmod.com> wrote:
>>> On Tue, 28 Jul 2009 03:35:55 -0700 (PDT), jakecjacobson <jakecjacob... at gmail.com> wrote:
>>> > [snip]
>>> 
>>> >"Invalid how? ?Self signed certificate? Domain mismatch? Expired
>>> >certificate?" ?It is a server name mismatch.
>>> 
>>> Python 2.4 is not capable of allowing you to customize this verification
>>> behavior. ?It is hard coded to let OpenSSL make the decision about whether
>>> to accept the certificate or not.
>>> 
>>> Either M2Crypto or pyOpenSSL will let you ignore verification errors. ?The
>>> new ssl module in Python 2.6 may also as well.
>>> 
>>> Jean-Paul

>j> Thanks, I will look into these suggestions.


>j> 		# cert_file is a PEM formatted certificate chain file.
>j> 		connection = httplib.HTTPSConnection(host, int(port), key_file,
>j> cert_file)

What happens if you set cert_file to None? This would indicate that you
are not interested in the server's certificate.

By the way, is the cert_file you supply the certificate of the CA that
signed the server's cert (in contrast to yours)?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From lkcl at lkcl.net  Tue Jul 28 15:56:29 2009
From: lkcl at lkcl.net (Luke Kenneth Casson Leighton)
Date: Tue, 28 Jul 2009 19:56:29 +0000
Subject: [ANN] Pyjamas 0.6pre2 Python Web Widget Set and Javascript Compiler
Message-ID: <ced5f0f60907281256m19ac88c9n8231991593352116@mail.gmail.com>

http://pyjs.org

this is a pre-release announcement, 0.6pre2, of the pyjamas widget set
and python-to-javascript compiler.  there are over 110 entries in the
CHANGELOG since the last stable release, 0.5p1, and so it was deemed
sensible to invite people to test this version before its next stable
release, 0.6.

pyjamas, being a port of GWT to python, comprises four main components:
* a stand-alone python-to-javascript compiler
* a desktop-based wrapper around python-xpcom or pywebkitgtk
* a browser "DOM" model wrapper interface
* a widget set similar to pygtk2 / pyqt4, based on DOM manipulation

significantly in the 0.6 series, pyjamas-desktop has been incorporated
into the build: "python Hello.py" will start a stand-alone app (just
as you would with pygtk2 or pyqt4) and "pyjsbuild Hello" will compile
the javascript version(s).

the combination means that pyjamas can run python applications -
unmodified - in all major web browsers, or on the desktop (using gecko
or webkit) in a similar fashion to adobe AIR.

in the javascript version: somewhere along the line, a massive
performance hit was introduced by accident. this has now been fixed.
however, random desperate attempts to improve performance, before the
mistake was corrected, mean that the pyjamas 0.6pre2
python-to-javascript compiler produces code that is stunningly quick.

also in the 0.6pre2 release, "strict" python options have now been
introduced, so that developers can expect much more support for the
standard python 2.5 / 2.6 language semantics.  the "-O" option
disables many of these features, bringing a quite significant speed
increase, by sacrificing python compatibility.  that's just the way it
has to be.

downloads can be found by following the links from http://pyjs.org -
sourceforge, code.google.com, pypi, all the usual places.

lastly - thank you to everyone who's helped with pyjamas: bernd,
bernd, jurgen, christian, kees, ondrej and many more, and especially
thank you to the people who helped out by pointing out bugs in the
0.6pre1 release, please keep it up!

l.


From electriclightheads at gmail.com  Tue Jul 28 15:59:37 2009
From: electriclightheads at gmail.com ('2+)
Date: Wed, 29 Jul 2009 04:59:37 +0900
Subject: instead of depending on data = array('h') .. write samples 1 by 1 to 
	w = wave.open("wav.wav", "w")
Message-ID: <1078018b0907281259m63d9cbeeyb6f908f240afa6a2@mail.gmail.com>

it says
Wave_write.writeframes(data)
will that mean
"from array import array"
is a must?

this does the job:

import oil
import wave
from array import array

a = oil.Sa()

w = wave.open("current.wav", "w")
w.setnchannels(2)
w.setsampwidth(2)
w.setframerate(44100)

data = array('h')

for gas in range(44100 * 5):
    a.breath()
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    data.append(r)
    data.append(l)

w.writeframes(data.tostring())
w.close()

don't like array becoming so huge so tested this and it was also okay:

for gas in range(44100 * 5):
    a.breath()
    data = array('h')
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    data.append(r)
    data.append(l)
    w.writeframes(data.tostring())

but without array .. it becomes 15secs(3 times longer than was
intended to be) of wav file:

for gas in range(44100 * 5):
    a.breath()
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    w.writeframes(hex(r))
    w.writeframes(hex(l))

should i just be happy with depennding on using array?
or is there a solution to make the last one work properly?

tia

-- 
SaRiGaMa's Oil Vending Orchestra
is podcasting:
http://sarigama.namaste.jp/podcast/rss.xml
and supplying oil.py for free:
http://oilpy.blogspot.com/


From leerisq at gmail.com  Tue Jul 28 16:05:16 2009
From: leerisq at gmail.com (LeeRisq)
Date: Tue, 28 Jul 2009 13:05:16 -0700 (PDT)
Subject: xlrd - insert column?
Message-ID: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>

Does xlrd have the capability to insert a column?


From wilk at flibuste.net  Tue Jul 28 16:05:35 2009
From: wilk at flibuste.net (William Dode)
Date: 28 Jul 2009 20:05:35 GMT
Subject: New implementation of re module
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<mailman.3792.1248722883.8015.python-list@python.org>
	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
	<mailman.3850.1248801945.8015.python-list@python.org>
Message-ID: <4a6f5a0f$0$25500$426a74cc@news.free.fr>

On 28-07-2009, MRAB wrote:

> With the official Python 2.6 distribution for Mac OS X it works.
>> 
> The source code is intended to replace the current 're' module in Python
> 2.7 (and I'll be porting it to Python 3.2), so I'm not that worried
> about Python versions earlier than 2.6 for testing, although if there's
> sufficient need then I could tweak the sources for 2.5.

I understand now why i could'nt compile it !

So, i would like if it's not too much work for you.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From bsagert at gmail.com  Tue Jul 28 16:16:30 2009
From: bsagert at gmail.com (Bill)
Date: Tue, 28 Jul 2009 13:16:30 -0700 (PDT)
Subject: Need help in passing a "-c command" argument to the interactive 
	shell.
Message-ID: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>

On my windows box I type => c:\x>python -c "import re"

The result is => c:\x>

In other words, the Python interactive shell doesn't even open. What
am I doing wrong?

I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
argument passing, but to no avail.


From doug.farrell at gmail.com  Tue Jul 28 16:21:47 2009
From: doug.farrell at gmail.com (writeson)
Date: Tue, 28 Jul 2009 13:21:47 -0700 (PDT)
Subject: Extract images from PDF files
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
	<mailman.3815.1248752499.8015.python-list@python.org>
Message-ID: <bb3c4944-596f-478f-8c34-0478fbbbe9dd@q35g2000vbi.googlegroups.com>

David,

Thanks for your reply, I'll take a look at pdftohtml and see if it
suits my needs.

Thanks!
Doug


From insyte at gmail.com  Tue Jul 28 16:24:15 2009
From: insyte at gmail.com (Ben)
Date: Tue, 28 Jul 2009 13:24:15 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com> 
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com> 
	<16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com> 
	<524a57a9-ba45-459b-b62d-81f527888a4e@j19g2000vbp.googlegroups.com>
Message-ID: <8d2e92fd-a7a1-40fb-8586-808c29dee31c@d32g2000yqh.googlegroups.com>

On Jul 22, 1:04?pm, davidj411 <davidj... at gmail.com> wrote:

> i think "Piet van Oostrum" has resolved my issue.
> good eyes!

Well, he *is* Dutch...

-Ben


From vs at it.uu.se  Tue Jul 28 16:28:09 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Tue, 28 Jul 2009 22:28:09 +0200
Subject: "Deprecated sets module" with Python 2.6
Message-ID: <4A6F5F59.4080507@it.uu.se>

I would appreciate help on correcting a problem when trying to create an 
*.exe file using py2exe via GUI2exe with Python 2.6.2.

When using GUI2exe to create an *.exe I always get the following warning 
during the compile process:

 C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
 DeprecationWarning: the sets module is deprecated
 import sets

and this results in the creation of an *.exe file that can not be executed.

On the other hand, if I use the same procedure (on the same Python code) 
with
Python 2.5, there are no warnings and the *.exe works fine.

The procedure used is that given in the example "Less simpler one" at
 
  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin

Any suggestions, help, ... would be greatly appreciated.

Thanks,
--V.



From tino at wildenhain.de  Tue Jul 28 16:36:57 2009
From: tino at wildenhain.de (Tino Wildenhain)
Date: Tue, 28 Jul 2009 22:36:57 +0200
Subject: xlrd - insert column?
In-Reply-To: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>
References: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>
Message-ID: <4A6F6169.6030409@wildenhain.de>

LeeRisq wrote:
> Does xlrd have the capability to insert a column?

rd means ReaD, so there is nothing it could insert
something to. Of course once you have read the data
you can manipulate its structure how you like it.

The counterpart is xlwt and it can write excel files
however you like it.

Regards
Tino


From philip at semanchuk.com  Tue Jul 28 16:45:08 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Tue, 28 Jul 2009 16:45:08 -0400
Subject: Need help in passing a "-c command" argument to the interactive
	shell.
In-Reply-To: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
References: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
Message-ID: <8ACF1BB9-CC8B-4D3C-88D3-6A81C56F99A9@semanchuk.com>


On Jul 28, 2009, at 4:16 PM, Bill wrote:

> On my windows box I type => c:\x>python -c "import re"
>
> The result is => c:\x>
>
> In other words, the Python interactive shell doesn't even open. What
> am I doing wrong?

Nothing! =) The -c option tells Python to execute the commands in the  
quotes as a Python program. It's as if you wrote a Python program that  
contained only "import re" and then executed that program.

If you want to run the Python interpreter interactively, just type  
"python" (no quotes) at the command prompt and hit enter.


> I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
> argument passing, but to no avail.

Yikes, that's the documentation for Python 1.5.2 which is nine years  
old! If that's the version you're running, then it's appropriate to  
read that documentation, but that's probably not the case.

"python --version" (again, no quotes) should tell you what version  
you're running.

HTH
Philip



From mark at markroseman.com  Tue Jul 28 16:47:14 2009
From: mark at markroseman.com (Mark Roseman)
Date: Tue, 28 Jul 2009 14:47:14 -0600
Subject: need help using Tkinter
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
	<mailman.3847.1248795167.8015.python-list@python.org>
Message-ID: <mark-906AAB.14471428072009@nothing.attdns.com>

 MRAB <python at mrabarnett.plus.com> wrote:
> Manzur Ahmed wrote:
> > i wanted to ask you if one of you could help me to use Tkinter. i'm 
> > trying to just create a simple GUI for which I have provided the code 
> > for below.
> There are some differences between Python 3.x and Python 2.x. In Python
> 3.1 the module is called "tkinter", not "Tkinter" (names are
> case-sensitive).


Further to the above, you can find my Tkinter tutorial (which uses 
Python 3.x) at http://www.tkdocs.com -- I hope this will provide some 
help in getting up to speed.

Mark


From python at mrabarnett.plus.com  Tue Jul 28 16:47:45 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 21:47:45 +0100
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <4A6F5F59.4080507@it.uu.se>
References: <4A6F5F59.4080507@it.uu.se>
Message-ID: <4A6F63F1.4080502@mrabarnett.plus.com>

Virgil Stokes wrote:
> I would appreciate help on correcting a problem when trying to create an 
> *.exe file using py2exe via GUI2exe with Python 2.6.2.
> 
> When using GUI2exe to create an *.exe I always get the following warning 
> during the compile process:
> 
> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
> DeprecationWarning: the sets module is deprecated
> import sets
> 
> and this results in the creation of an *.exe file that can not be executed.
> 
> On the other hand, if I use the same procedure (on the same Python code) 
> with
> Python 2.5, there are no warnings and the *.exe works fine.
> 
> The procedure used is that given in the example "Less simpler one" at
> 
>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
> 
> Any suggestions, help, ... would be greatly appreciated.
> 
The 'sets' module is deprecated in Python 2.6 because 'set' was added as
a new builtin class. I don't know why that would result in a .exe file
that can't be executed.


From breamoreboy at yahoo.co.uk  Tue Jul 28 16:49:53 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Tue, 28 Jul 2009 21:49:53 +0100
Subject: Need help in passing a "-c command" argument to the interactive
	shell.
In-Reply-To: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
References: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
Message-ID: <h4no8c$5rm$1@ger.gmane.org>

Bill wrote:
> On my windows box I type => c:\x>python -c "import re"
> 
> The result is => c:\x>
> 
> In other words, the Python interactive shell doesn't even open. What
> am I doing wrong?
> 
> I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
> argument passing, but to no avail.
You've told python to run the command "import re" which it's happily 
done before exiting.  Simply type python, then at the prompt (default 
 >>>) type whatever commands you wish, e.g.

c:\Users\Mark\python\regex>python
Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit 
(Intel)] on
win32
Type "help", "copyright", "credits" or "license" for more information.
 >>> import re
 >>> help(re.compile)
Help on function compile in module re:

compile(pattern, flags=0)
     Compile a regular expression pattern, returning a pattern object.

 >>>

-- 
Kindest regards.

Mark Lawrence.



From shai at platonix.com  Tue Jul 28 16:49:57 2009
From: shai at platonix.com (Shai)
Date: Tue, 28 Jul 2009 13:49:57 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au> <87ljmogglz.fsf@benfinney.id.au> 
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
	<056f629b-aa63-458a-ae16-ac40a759e446@h11g2000yqb.googlegroups.com>
	<h4hu96$8hs$1@panix3.panix.com>
Message-ID: <db31afcb-0ff5-4a1d-a295-1b0830256913@a26g2000yqn.googlegroups.com>

On Jul 26, 6:55?pm, a... at pythoncraft.com (Aahz) wrote:
>
> Nice! ?Maybe stick this on the Cookbook?

http://code.activestate.com/recipes/576862/

Thanks for the suggestion,

Shai.


From aahz at pythoncraft.com  Tue Jul 28 16:57:37 2009
From: aahz at pythoncraft.com (Aahz)
Date: 28 Jul 2009 13:57:37 -0700
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<h4lp5a$ehd$1@panix3.panix.com>
	<mailman.3843.1248793153.8015.python-list@python.org>
Message-ID: <h4noo1$kr6$1@panix3.panix.com>

In article <mailman.3843.1248793153.8015.python-list at python.org>,
MRAB  <python at mrabarnett.plus.com> wrote:
>Aahz wrote:
>> In article <mailman.3787.1248712420.8015.python-list at python.org>,
>> MRAB  <python at mrabarnett.plus.com> wrote:
>>> I've been working on a new implementation of the re module. The details
>>> are at http://bugs.python.org/issue2636, specifically from
>>> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>>> Python 2.6 on Windows if you want to try it out.
>> 
>> How does it handle the re module's unit tests?
>
>Basically, it passes all those tests I expect it to pass. :-)
>
>It fails those where the intended behaviour has changed, such as re.sub
>treating unmatched groups as empty strings, as requested in
>http://bugs.python.org/issue1519638.

Then you should definitely publish to PyPI and post a message to
c.l.py.announce to get more users.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From REMOVEmagicus23THIS at gmail.com  Tue Jul 28 17:25:09 2009
From: REMOVEmagicus23THIS at gmail.com (magicus)
Date: Tue, 28 Jul 2009 21:25:09 +0000 (UTC)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
	<200907281035.48713.hendrik@microcorp.co.za>
	<mailman.3844.1248793868.8015.python-list@python.org>
Message-ID: <h4nqbk$r8h$1@news.eternal-september.org>

On Tue, 28 Jul 2009 16:11:02 +0100, MRAB <python at mrabarnett.plus.com>
wrote:

> Hendrik van Rooyen wrote:
>> On Monday 27 July 2009 16:49:25 Aahz wrote:
>>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>>
>>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>>> I have searched, but I can find nothing about this mediocre language.
>>>>
>>>> Could you tell us more?
>>>>
>>> :-P
>>>
>>> (For anyone who is confused by Hendrik's humor, he is saying that
>>> David was referring to a programming language named "mediocre". 
>>> English grammar is confusing!)
>> 
>> This is true - I intended, when I started the post, to make a crack
>> about how he knew that he was mediocre - If there were some exam or
>> test that you have to pass or fail to be able to make the claim to
>> mediocrity. I was imagining a sort of devil's rating scale for
>> programmers, that could cause one to say things like:  "I am studying
>> hard so that I can get my mediocre certificate, and one day I hope to
>> reach hacker rank".
>> 
>> And then the similarity to "I am a COBOL programmer" struck me, and I
>> abandoned the ratings.
>> 
> If you were a "COBOL" programmer, would you want to shout about it? :-)

The last time I wrote anything in COBOL was sometime in the early 80s.
Somehow that makes me feel good, heh.

ciao,
f

-- 
?Using words to describe magic is like using a screwdriver to cut roast 
beef.?
-- Tom Robbins


From deets at nospam.web.de  Tue Jul 28 17:36:19 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 28 Jul 2009 23:36:19 +0200
Subject: C function taking double pointer to a structure variable as OUTPUT
	parameter
In-Reply-To: <mailman.3852.1248806955.8015.python-list@python.org>
References: <mailman.3852.1248806955.8015.python-list@python.org>
Message-ID: <7d99akF2at9g3U1@mid.uni-berlin.de>

fengmang_python at sina.com schrieb:
> Hi, Everyone,
> 
> I am a newbie to both Swig and Python. I am trying to export a set of C 
> APIs to Python.

If you are really dealing with a plain C-api, don't bother using SWIG - 
use ctypes. It comes with python >=2.5, is availabe as extra module for 
earlier versions, and makes wrapping C-libs a breeze.

Diez


From li.weidong at gmail.com  Tue Jul 28 17:41:30 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 14:41:30 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
	<mailman.3837.1248790649.8015.python-list@python.org>
	<1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>
	<mailman.3849.1248799068.8015.python-list@python.org>
Message-ID: <bd945ca4-f62a-47fa-92d5-d4a7047d4411@r24g2000vbn.googlegroups.com>

On Jul 28, 12:37?pm, Christian Heimes <li... at cheimes.de> wrote:
> 'make install' shouldn't compile any libraries if you run 'make' prior
> to 'make install'. I suggest you start again with a clean build tree of
> Python 2.6.2.
>
> Christian

You are perfectly right.  I started everything again after a "make
distclean".  This time I configured it as follows:

./configure --enable-unicode=ucs2 --enable-shared

to make things explicit, although I guess that the defaults would be
the same even when "--enable-unicode=ucs2 --enable-shared" are not
specified (in my case where ucs4 is not available).  The Makefile
generated then contains meaningful flags in RUNSHARED which was absent
before.

With this configuration, "make" was fine, except it "only" has the
following problems:

Failed to find the necessary bits to build these modules:
bsddb185           gdbm               sunaudiodev
To find the necessary bits, look in setup.py in detect_modules() for
the module's name.

That was not surprised because I did not have those available on my
machine.

The unicodedata.so was also created in the "make" process, and "make
install" showed no problem.

"make test" showed the following problems:

test_aepack
test_aepack skipped -- No module named aepack
test_al
test_al skipped -- No module named al
test_anydbm
Exception bsddb.db.DBRunRecoveryError: DBRunRecoveryError(-30974,
'DB_RUNRECOVERY: Fatal error, run database recovery -- PANIC: fatal
region error detected; run recovery') in  ignored

I guess this is caused by the missing bsddb185.  However, the problem
is, "make test" seemed to be hanging at that fatal error.

Do you know how critical are those failed tests?

Thanks for your help!

- Weidong


From deets at nospam.web.de  Tue Jul 28 17:45:45 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 28 Jul 2009 23:45:45 +0200
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <mailman.3856.1248812897.8015.python-list@python.org>
References: <mailman.3856.1248812897.8015.python-list@python.org>
Message-ID: <7d99s9F28m0aaU1@mid.uni-berlin.de>

Virgil Stokes schrieb:
> I would appreciate help on correcting a problem when trying to create an 
> *.exe file using py2exe via GUI2exe with Python 2.6.2.
> 
> When using GUI2exe to create an *.exe I always get the following warning 
> during the compile process:
> 
> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
> DeprecationWarning: the sets module is deprecated
> import sets
> 
> and this results in the creation of an *.exe file that can not be executed.
> 
> On the other hand, if I use the same procedure (on the same Python code) 
> with
> Python 2.5, there are no warnings and the *.exe works fine.
> 
> The procedure used is that given in the example "Less simpler one" at
> 
>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
> 
> Any suggestions, help, ... would be greatly appreciated.

If you don't need your app running on python2.3 and earlier, just remove 
the sets-module and replace it with the builtin "set".

Diez


From bakes at ymail.com  Tue Jul 28 17:59:26 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 14:59:26 -0700 (PDT)
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
	<fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com> 
	<mailman.3848.1248799038.8015.python-list@python.org>
Message-ID: <6bf6294f-eb85-48b8-9b15-64fd20eb5989@32g2000yqj.googlegroups.com>

On Jul 28, 5:36?pm, Dave Angel <da... at ieee.org> wrote:
> Bakes wrote:
> > On 28 July, 15:18, Bakes <ba... at ymail.com> wrote:
>
> >> On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
>
> >>> Bakes <ba... at ymail.com> writes:
>
> >>>> The error I get is:
> >>>> ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> >>>> 22852.
> >>>> 451 Restart offset reset to 0
> >>>> which tells me that the local file is larger than the external file,
> >>>> by about a kilobyte. Certainly, the local file is indeed that size, so
> >>>> my local script is doing the right things. I do wonder what is going
> >>>> wrong, can anyone enlighten me?
>
> >>> I'd say you failed to take buffering into account. ?You write into a
> >>> buffered file, yet you use os.path.getsize() to find out the current
> >>> file size. ?If the data is not yet flushed, you keep re-reading the same
> >>> stuff from the remote file, and writing it out. ?Once the buffer is
> >>> flushed, your file will contain more data than was retrieved from the
> >>> remote side, and eventually this will result in the error you see.
>
> >>> As a quick fix, you can add a file.flush() line after the
> >>> file.write(...) line, and the problem should go away.
>
> >> Thank you very much, that worked perfectly.
>
> > Actually, no it didn't. That fix works seamlessly in Linux, but gave
> > the same error in a Windows environment. Is that expected?
>
> This is a text file you're transferring. ?And you didn't specify "wb". ?
> So the Windows size will be larger than the Unix size, since you're
> expanding the newline characters.
>
> getsize() is looking at the size after newlines are expanded to 0d0a,
> while The remote file, presumably a Unix system likely has just has 0a.
>
> I think you'd do best just keeping track of the bytes you've written.
>
> DaveA

Thank you very much, that worked perfectly.


From jdgiotta at gmail.com  Tue Jul 28 18:15:35 2009
From: jdgiotta at gmail.com (John D Giotta)
Date: Tue, 28 Jul 2009 15:15:35 -0700 (PDT)
Subject: Semaphore Techniques
Message-ID: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>

I'm looking to run a process with a limit of 3 instances, but each
execution is over a crontab interval. I've been investigating the
threading module and using daemons to limit active thread objects, but
I'm not very successful at grasping the documentation.

Is it possible to do what I'm trying to do and if so anyone know of a
useful example to get started?


From python at mrabarnett.plus.com  Tue Jul 28 18:22:29 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 23:22:29 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4nqbk$r8h$1@news.eternal-september.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<mailman.3765.1248685391.8015.python-list@python.org>	<h4kepl$qhf$1@panix3.panix.com>	<200907281035.48713.hendrik@microcorp.co.za>	<mailman.3844.1248793868.8015.python-list@python.org>
	<h4nqbk$r8h$1@news.eternal-september.org>
Message-ID: <4A6F7A25.3010004@mrabarnett.plus.com>

magicus wrote:
> On Tue, 28 Jul 2009 16:11:02 +0100, MRAB <python at mrabarnett.plus.com>
> wrote:
> 
>> Hendrik van Rooyen wrote:
>>> On Monday 27 July 2009 16:49:25 Aahz wrote:
>>>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>>>
>>>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>>>> I have searched, but I can find nothing about this mediocre language.
>>>>>
>>>>> Could you tell us more?
>>>>>
>>>> :-P
>>>>
>>>> (For anyone who is confused by Hendrik's humor, he is saying that
>>>> David was referring to a programming language named "mediocre". 
>>>> English grammar is confusing!)
>>> This is true - I intended, when I started the post, to make a crack
>>> about how he knew that he was mediocre - If there were some exam or
>>> test that you have to pass or fail to be able to make the claim to
>>> mediocrity. I was imagining a sort of devil's rating scale for
>>> programmers, that could cause one to say things like:  "I am studying
>>> hard so that I can get my mediocre certificate, and one day I hope to
>>> reach hacker rank".
>>>
>>> And then the similarity to "I am a COBOL programmer" struck me, and I
>>> abandoned the ratings.
>>>
>> If you were a "COBOL" programmer, would you want to shout about it? :-)
> 
> The last time I wrote anything in COBOL was sometime in the early 80s.
> Somehow that makes me feel good, heh.
> 
COBOL: it feels good when you stop. :-)

(I was actually referring to the convention of all capitals representing
shouting.)


From REMOVEmagicus23THIS at gmail.com  Tue Jul 28 18:26:28 2009
From: REMOVEmagicus23THIS at gmail.com (magicus)
Date: Tue, 28 Jul 2009 22:26:28 +0000 (UTC)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
	<200907281035.48713.hendrik@microcorp.co.za>
	<mailman.3844.1248793868.8015.python-list@python.org>
	<h4nqbk$r8h$1@news.eternal-september.org>
	<mailman.3861.1248819752.8015.python-list@python.org>
Message-ID: <h4ntuk$s00$1@news.eternal-september.org>

On Tue, 28 Jul 2009 23:22:29 +0100, MRAB <python at mrabarnett.plus.com>
wrote:

> magicus wrote:
>> On Tue, 28 Jul 2009 16:11:02 +0100, MRAB <python at mrabarnett.plus.com>
>> wrote:
>> 
>>> Hendrik van Rooyen wrote:
>>>> On Monday 27 July 2009 16:49:25 Aahz wrote:
>>>>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>>>>
>>>>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>>>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>>>>> I have searched, but I can find nothing about this mediocre
>>>>>> language.
>>>>>>
>>>>>> Could you tell us more?
>>>>>>
>>>>> :-P
>>>>>
>>>>> (For anyone who is confused by Hendrik's humor, he is saying that
>>>>> David was referring to a programming language named "mediocre".
>>>>> English grammar is confusing!)
>>>> This is true - I intended, when I started the post, to make a crack
>>>> about how he knew that he was mediocre - If there were some exam or
>>>> test that you have to pass or fail to be able to make the claim to
>>>> mediocrity. I was imagining a sort of devil's rating scale for
>>>> programmers, that could cause one to say things like:  "I am studying
>>>> hard so that I can get my mediocre certificate, and one day I hope to
>>>> reach hacker rank".
>>>>
>>>> And then the similarity to "I am a COBOL programmer" struck me, and I
>>>> abandoned the ratings.
>>>>
>>> If you were a "COBOL" programmer, would you want to shout about it?
>>> :-)
>> 
>> The last time I wrote anything in COBOL was sometime in the early 80s.
>> Somehow that makes me feel good, heh.
>> 
> COBOL: it feels good when you stop. :-)
> 

It certainly does!

> (I was actually referring to the convention of all capitals representing
> shouting.)

I rarely shout and I thought that to this day it was still referred to as 
COBOL. I am still glad that I never pursued a career in dealing w/ such a 
language.

ciao,
f

-- 
"What you resist, persists."


From li.weidong at gmail.com  Tue Jul 28 18:31:05 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 15:31:05 -0700 (PDT)
Subject: Questions on python 2.6.2 installed files
Message-ID: <42bdecab-7b61-49d4-9d3b-52c14024c20f@r34g2000vba.googlegroups.com>

I would like to build a python 2.6.2 for Linux that runs on arm-based
embeded devices.  After some experiment of building from the python
2.6.2 source, I notice that the installed files from "make install"
are much too big for an embedded system.  For example, the files it
installs to /usr/local/lib/python2.6/ dir is over 350MB.

>From the following installed files,

/usr/local/bin/python
/usr/local/lib/libpython2.6.so.1.0

I do not see they have any "direct" dependency on the files installed
in /usr/local/lib/python2.6 dir.  What are the use of those files in /
usr/local/lib/python2.6?  What is the consequence if I do not put them
on the embedded system?

Is there a good way to directly make an installation "package" (or
tarball) of python 2.6.2 from the build result?

Any advice on configuration to make the results smaller will be
greatly appreciated!

- Weidong


From breamoreboy at yahoo.co.uk  Tue Jul 28 18:40:02 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Tue, 28 Jul 2009 23:40:02 +0100
Subject: New implementation of re module
In-Reply-To: <4A6DD6FB.8040609@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
Message-ID: <h4nuli$orm$1@ger.gmane.org>

MRAB wrote:
> Hi all,
> 
> I've been working on a new implementation of the re module. The details
> are at http://bugs.python.org/issue2636, specifically from
> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
> Python 2.6 on Windows if you want to try it out.
> 
> I'm interested in how fast it is generally, compared with the current re
> module, but especially when faced with those 'pathological' regular
> expressions which seem to take a long time to finish, for example:
> 
>     re.search(r"^(.+|D)*A$", "x" * 25 + "B")
> 
> which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs 
> with this new implementation.
I tried this on my 3GHz PC timings pretty much the same.

 From here http://bugs.python.org/issue1721518 I knocked up this.

import time
import re
import regex

s = "Add.1, 2020 and Add.1, 2021-2023, 2025, 2028 and 2029 and Add.1) R"
r = "(?:\s|,|and|Add\S*?|Parts?|\([^\)]*\)|[IV\-\d]+)*$"
t0 = time.clock()
print regex.search(r, s)
t1 = time.clock()
print "time", t1 - t0

print "It's going to crash"
t0 = time.clock()
print re.search(r, s)
t1 = time.clock()
print "It hasn't crashed time", t1 - t0

Output shows a slight change in timing:).

<_regex.RE_Match object at 0x0243A1A0>
time 0.00279001940191
It's going to crash
<_sre.SRE_Match object at 0x024396B0>
It hasn't crashed time 98.4238155967

> 
> TIA

I also got the files bm_regex_effbot.py and bm_regex_v8.py from
http://code.google.com/p/unladen-swallow/source/browse/#svn/tests/performance 
and ran them, then reran them having substituted regex for re.  Output 
timings were roughly effbot re 0.14secs, effbot regex 1.16secs, v8 re 
0.17secs and v8 regex 0.67secs.

HTH.

-- 
Kindest regards.

Mark Lawrence.



From steve at REMOVE-THIS-cybersource.com.au  Tue Jul 28 18:49:00 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 28 Jul 2009 22:49:00 GMT
Subject: "Deprecated sets module" with Python 2.6
References: <mailman.3856.1248812897.8015.python-list@python.org>
Message-ID: <027f7136$0$5185$c3e8da3@news.astraweb.com>

On Tue, 28 Jul 2009 22:28:09 +0200, Virgil Stokes wrote:

> When using GUI2exe to create an *.exe I always get the following warning
> during the compile process:
> 
>  C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>  DeprecationWarning: the sets module is deprecated 
>  import sets

The best solution would be to change every call to sets.Set() to set(), 
and change the line:

import sets

to this:

try:
    set
except NameError:
    from sets import Set as set


If you use sets.ImmutableSet, you will need to change that to frozenset 
in the same way.

This assumes you don't need to support older versions of Python, before 
set() became a built-in.



-- 
Steven



From thebiggestbangtheory at gmail.com  Tue Jul 28 19:12:19 2009
From: thebiggestbangtheory at gmail.com (nickname)
Date: Tue, 28 Jul 2009 16:12:19 -0700 (PDT)
Subject: Regular expression solution
Message-ID: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>

Hello all,
            I'm a newbie with python. I am looking to write a regex
program which can take in a piece of text and remove some parts of it
and supply the remaining parts back.

The input can be something like:
<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
" is  "+"21c";)</script>

The output should be something like
<script>document.write("hellooooo my name is  21c";)</script>

I have tried and failed. I am reading http://www.amk.ca/python/howto/regex/
and hope to get somewhere with this soon. If this is something simple,
can someone please help me out.

Thanks in advance for any help.




From contact at xavierho.com  Tue Jul 28 19:15:34 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 09:15:34 +1000
Subject: Extract images from PDF files
In-Reply-To: <bb3c4944-596f-478f-8c34-0478fbbbe9dd@q35g2000vbi.googlegroups.com>
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
	<mailman.3815.1248752499.8015.python-list@python.org>
	<bb3c4944-596f-478f-8c34-0478fbbbe9dd@q35g2000vbi.googlegroups.com>
Message-ID: <2d56febf0907281615g798087dcrb98b3b283befee71@mail.gmail.com>

I've got a non-Python solution if you have Acrobat 6 or up.

>From the menu, Advanced -> Document Processing -> Extract All Images...

If you need multiple PDFs done, Batch Processing would be a great start.

Then you can run another script to make the thumbnails, or use Photoshop.
Either way works!

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Wed, Jul 29, 2009 at 6:21 AM, writeson <doug.farrell at gmail.com> wrote:

> David,
>
> Thanks for your reply, I'll take a look at pdftohtml and see if it
> suits my needs.
>
> Thanks!
> Doug
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/3efb6e59/attachment.html>

From lists at cheimes.de  Tue Jul 28 19:19:41 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 29 Jul 2009 01:19:41 +0200
Subject: Semaphore Techniques
In-Reply-To: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <4A6F878D.6010403@cheimes.de>

John D Giotta schrieb:
> I'm looking to run a process with a limit of 3 instances, but each
> execution is over a crontab interval. I've been investigating the
> threading module and using daemons to limit active thread objects, but
> I'm not very successful at grasping the documentation.
> 
> Is it possible to do what I'm trying to do and if so anyone know of a
> useful example to get started?

Since you are talking about crontab I assume that you are on an os that
supports pthreads. You problem can easily be solved with a named
semaphore (see sem_open(3) and sem_overview(7)). Unfortunately Python
doesn't expose named semaphores. The multiprocessing library uses named
semaphores but you can't set the name yourself.

You have to write your own C wrapper or search on pypi and through
Google. If you are going to write your own semaphore I highly recommend
Cython.

Christian


From philip at semanchuk.com  Tue Jul 28 19:26:53 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Tue, 28 Jul 2009 19:26:53 -0400
Subject: Semaphore Techniques
In-Reply-To: <4A6F878D.6010403@cheimes.de>
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<4A6F878D.6010403@cheimes.de>
Message-ID: <D52D9110-35B7-4404-B1D4-BB6DE2E16A53@semanchuk.com>


On Jul 28, 2009, at 7:19 PM, Christian Heimes wrote:

> John D Giotta schrieb:
>> I'm looking to run a process with a limit of 3 instances, but each
>> execution is over a crontab interval. I've been investigating the
>> threading module and using daemons to limit active thread objects,  
>> but
>> I'm not very successful at grasping the documentation.
>>
>> Is it possible to do what I'm trying to do and if so anyone know of a
>> useful example to get started?
>
> Since you are talking about crontab I assume that you are on an os  
> that
> supports pthreads. You problem can easily be solved with a named
> semaphore (see sem_open(3) and sem_overview(7)). Unfortunately Python
> doesn't expose named semaphores. The multiprocessing library uses  
> named
> semaphores but you can't set the name yourself.
>
> You have to write your own C wrapper or search on pypi and through
> Google. If you are going to write your own semaphore I highly  
> recommend
> Cython.

My POSIX IPC extension permits manipulation of interprocess semaphores:
http://semanchuk.com/philip/posix_ipc/

There's also one for SysV IPC:
http://semanchuk.com/philip/sysv_ipc/

Enjoy
P



From db3l.net at gmail.com  Tue Jul 28 19:30:21 2009
From: db3l.net at gmail.com (David Bolen)
Date: Tue, 28 Jul 2009 19:30:21 -0400
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <m2bpn44c8i.fsf@valheru.db3l.homeip.net>

John D Giotta <jdgiotta at gmail.com> writes:

> I'm looking to run a process with a limit of 3 instances, but each
> execution is over a crontab interval. I've been investigating the
> threading module and using daemons to limit active thread objects, but
> I'm not very successful at grasping the documentation.
>
> Is it possible to do what I'm trying to do and if so anyone know of a
> useful example to get started?

Does it have to be built into the tool, or are you open to handling the
restriction right in the crontab entry?

For example, a crontab entry like:

  * * * * * test `pidof -x script.py | wc -w` -ge 4 || <path>/script.py

should attempt to run script.py every minute (adjust period as
required) unless there are already four of them running.  And if pidof
isn't precise enough you can put anything in there that would
accurately check your processes (grep a ps listing or whatever).

This works because if the test expression is true it returns 0 which
terminates the logical or (||) expression.

There may be some variations based on cron implementation (the above
was tested against Vixie cron), but some similar mechanism should be
available.

If you wanted to build it into the tool, it can be tricky in terms of
managing shared state (the count) amongst purely sibling/cooperative
processes.  It's much easier to ensure no overlap (1 instance), but
once you want 'n' instances you need an accurate process-wide counter.
I'm not positive, but don't think Python's built-in semaphores or
shared memory objects are cross-process.  (Maybe something in
multiprocessing in recent Python versions would work, though they may
need the sharing processes to all have been executed from a parent
script)

I do believe there are some third party interfaces (posix_ipc,
shm/shm_wrapper) that would provide access to posix shared-process
objects.  A semaphore may still not work as I'm not sure you can
obtain the current count.  But you could probably do something with
a shared memory counter in conjunction with a mutex of some sort, as
long as you were careful to clean it up on exit.

Or, you could stick PIDs into the shared memory and count PIDs on
a new startup (double checking against running processes to help
protect against process failures without cleanup).

You could also use the filesystem - have a shared directory where each
process dumps its PID, after first counting how many other PIDs are in
the directory and exiting if too many.

Of course all of these (even with a PID check) are risky in the
presence of unexpected failures.  It would be worse with something
like C code, but it should be reasonably easy to ensure that your
script has cleanup code even on an unexpected termination, and it's
not that likely the Python interpreter itself would crash.  Then
again, something external could kill the process.  Ensuring accuracy
and cleanup of shared state can be non-trivial.

You don't mention if you can support a single master daemon, but if
you could, then it can get a little easier as it can maintain and
protect access to the state - you could have each worker process
maintain a socket connection of some sort with the master daemon so it
could detect when they terminate for the count, and it could just
reject such connections from new processes if too many are running
already.  Of course, if the master daemon goes away then nobody would
run, which may or may not be an acceptable failure mode.

All in all, unless you need the scripts to enforce this behavior even
in the presence of arbitrary use, I'd just use an appropriate crontab
entry and move on to other problems :-)

-- David


From pavlovevidence at gmail.com  Tue Jul 28 19:36:49 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 28 Jul 2009 16:36:49 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>

On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
> I'm looking to run a process with a limit of 3 instances, but each
> execution is over a crontab interval. I've been investigating the
> threading module and using daemons to limit active thread objects, but
> I'm not very successful at grasping the documentation.
>
> Is it possible to do what I'm trying to do and if so anyone know of a
> useful example to get started?

It seems like you want to limit the number of processes to three; the
threading module won't help you there because it deals with threads
within a single process.

What I'd do is to simply run the system ps to see how many processes
are running (ps is pretty versatile on most systems and can find
specifically targeted processes like you program), and exit if there
are already three.

If you really are talking about multiple threads on a single server
process, then you want to use a thread pool (create three threads, and
give them tasks as necessary).  But you'll have to have a way for the
process started by crontab to communicate with the server.


Carl Banks


From zuo at chopin.edu.pl  Tue Jul 28 20:06:32 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Wed, 29 Jul 2009 02:06:32 +0200
Subject: need help using Tkinter
In-Reply-To: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
Message-ID: <op.uxsyk5owfvx12t@jerzozwiesz.home.aster.pl>

28-07-2009 o 17:17 Manzur Ahmed <dearmanzur at gmail.com> wrote:

> i wanted to ask you if one of you could help me to use Tkinter. i'm  
> trying
> to just create a simple GUI for which I have provided the code for below.
[snip]
> i tried to google search this and there were some threads that were  
> saying
> to install tcl but that does not work. I did check the Lib directory  
> under
> the Python directory and I did not see a Tkinter module anywhere which I
> think is the problem. Do you know how I would go about with getting this
> module and if that is not the problem or if you think it might be caused  
> by
> something else, can you please give me some guidance?

What operating system do you use?

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From sjmachin at lexicon.net  Tue Jul 28 20:26:40 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 28 Jul 2009 17:26:40 -0700 (PDT)
Subject: xlrd - insert column?
References: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>
Message-ID: <c6be7377-cfe4-4a93-b602-d448d0bfe5a7@g1g2000pra.googlegroups.com>

On Jul 29, 6:05?am, LeeRisq <leer... at gmail.com> wrote:
> Does xlrd have the capability to insert a column?

No. If there was anything in the PyPI description, the README, or the
docs that gave you the faintest hope that xlrd does anything other
than read Excel files, please raise a documentation bug-fix request.

Start here: http://www.python-excel.org and read the tutorial.

Cheers,

John


From nobody at nowhere.com  Tue Jul 28 20:45:08 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 01:45:08 +0100
Subject: bad certificate error
References: <mailman.3835.1248788885.8015.python-list@python.org>
	<332a5bba-48d5-4c8b-9c1e-288790d85dbb@o32g2000yqm.googlegroups.com>
	<m263dca8ze.fsf@cs.uu.nl>
Message-ID: <pan.2009.07.29.00.45.07.953000@nowhere.com>

On Tue, 28 Jul 2009 21:44:05 +0200, Piet van Oostrum wrote:

>>j> 		# cert_file is a PEM formatted certificate chain file.
>>j> 		connection = httplib.HTTPSConnection(host, int(port), key_file,
>>j> cert_file)
> 
> What happens if you set cert_file to None? This would indicate that you
> are not interested in the server's certificate.
> 
> By the way, is the cert_file you supply the certificate of the CA that
> signed the server's cert (in contrast to yours)?

The cert_file parameter is the client certificate. You must provide
either both key_file and cert_file, or neither.



From nobody at nowhere.com  Tue Jul 28 20:54:23 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 01:54:23 +0100
Subject: Regular expression solution
References: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>
Message-ID: <pan.2009.07.29.00.54.23.125000@nowhere.com>

On Tue, 28 Jul 2009 16:12:19 -0700, nickname wrote:

>             I'm a newbie with python. I am looking to write a regex
> program which can take in a piece of text and remove some parts of it
> and supply the remaining parts back.
> 
> The input can be something like:
> <script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
> " is  "+"21c";)</script>
> 
> The output should be something like
> <script>document.write("hellooooo my name is  21c";)</script>

import re
r = re.compile(r'"\s*\+\s*"')
s = r'''<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
" is  "+"21c";)</script>'''
r.sub('', s)



From python at mrabarnett.plus.com  Tue Jul 28 20:58:50 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 01:58:50 +0100
Subject: New implementation of re module
In-Reply-To: <4a6f5a0f$0$25500$426a74cc@news.free.fr>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<mailman.3792.1248722883.8015.python-list@python.org>	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>	<mailman.3850.1248801945.8015.python-list@python.org>
	<4a6f5a0f$0$25500$426a74cc@news.free.fr>
Message-ID: <4A6F9ECA.3010205@mrabarnett.plus.com>

William Dode wrote:
> On 28-07-2009, MRAB wrote:
> 
>> With the official Python 2.6 distribution for Mac OS X it works.
>> The source code is intended to replace the current 're' module in Python
>> 2.7 (and I'll be porting it to Python 3.2), so I'm not that worried
>> about Python versions earlier than 2.6 for testing, although if there's
>> sufficient need then I could tweak the sources for 2.5.
> 
> I understand now why i could'nt compile it !
> 
> So, i would like if it's not too much work for you.
> 
There's a new version which should compile with Python 2.5 now.


From cocobear.cn at gmail.com  Tue Jul 28 21:20:29 2009
From: cocobear.cn at gmail.com (cocobear)
Date: Tue, 28 Jul 2009 18:20:29 -0700 (PDT)
Subject: merge two png pic
Message-ID: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>

This two png file has their own palette

>>> im1.mode
'P'
>>> im.mode
'P'
>>> im.getpalette == im1.getpalette
False

I can use this code to merge two png pic together:

Map = Image.new("RGB", (x,y))
Map.paste(im, box)
Map.paste(im1,box)

Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)

But if the two png pic is too big , or if I have to merge more pic
together, I will get MemoryError:

>>> Image.new("RGB",(44544,38656))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
new
    return Image()._new(core.fill(mode, size, color))
MemoryError

How can I directly merge two pic to a ?P' mode png with palette.



From contact at xavierho.com  Tue Jul 28 21:29:15 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 11:29:15 +1000
Subject: merge two png pic
In-Reply-To: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
Message-ID: <2d56febf0907281829x4d43a1abse2c271ad857174c1@mail.gmail.com>

On Wed, Jul 29, 2009 at 11:20 AM, cocobear <cocobear.cn at gmail.com> wrote:

>
> >>> Image.new("RGB",(44544,38656))
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
> new
>    return Image()._new(core.fill(mode, size, color))
> MemoryError


a 44544x38656 pixel PNG file? I don't mean to be nosy, but what is this for,
if you could share?


> How can I directly merge two pic to a ?P' mode png with palette.


Save to disk incrementally is one way I can think of. It's a lot slower, but
definitely more space than your RAM.

Good luck,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/4519095d/attachment.html>

From icebergwtf at gmail.com  Tue Jul 28 23:11:28 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Wed, 29 Jul 2009 11:11:28 +0800
Subject: Regular expression solution
In-Reply-To: <pan.2009.07.29.00.54.23.125000@nowhere.com>
References: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>
	<pan.2009.07.29.00.54.23.125000@nowhere.com>
Message-ID: <4314c1f70907282011g799ccbf2tf44a4d4dd95dc8a7@mail.gmail.com>

2009/7/29 Nobody <nobody at nowhere.com>:
>> The output should be something like
>> <script>document.write("hellooooo my name is ?21c";)</script>
>
> import re
> r = re.compile(r'"\s*\+\s*"')
> s = r'''<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
> " is ?"+"21c";)</script>'''
> r.sub('', s)
>

Nobody's solution is good.
here is more complicated solution, just for regex practice :-)

>>> s = '<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+" is  "+"21c";)</script>'
>>> new_s = re.sub(r'(?<=")(.+)(?=")', ''.join(re.findall(r'"([^"]+)"', s)), s)
>>> new_s
'<script>document.write("hellooooo my name is  21c";)</script>'


From Brian.Mingus at colorado.edu  Tue Jul 28 23:42:31 2009
From: Brian.Mingus at colorado.edu (Brian)
Date: Tue, 28 Jul 2009 21:42:31 -0600
Subject: Regular expression solution
In-Reply-To: <4314c1f70907282011g799ccbf2tf44a4d4dd95dc8a7@mail.gmail.com>
References: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>
	<pan.2009.07.29.00.54.23.125000@nowhere.com>
	<4314c1f70907282011g799ccbf2tf44a4d4dd95dc8a7@mail.gmail.com>
Message-ID: <9839a05c0907282042w778caa87je53b3d34e4b00049@mail.gmail.com>

On Tue, Jul 28, 2009 at 9:11 PM, tiefeng wu <icebergwtf at gmail.com> wrote:

> 2009/7/29 Nobody <nobody at nowhere.com>:
> >> The output should be something like
> >> <script>document.write("hellooooo my name is  21c";)</script>
> >
> > import re
> > r = re.compile(r'"\s*\+\s*"')
> > s = r'''<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+"
> n"+"ame"+
> > " is  "+"21c";)</script>'''
> > r.sub('', s)
> >
>
> Nobody's solution is good.
> here is more complicated solution, just for regex practice :-)
>
> >>> s = '<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+"
> n"+"ame"+" is  "+"21c";)</script>'
> >>> new_s = re.sub(r'(?<=")(.+)(?=")', ''.join(re.findall(r'"([^"]+)"',
> s)), s)
> >>> new_s
> '<script>document.write("hellooooo my name is  21c";)</script>'
> --
> http://mail.python.org/mailman/listinfo/python-list
>

 >>> from time import time>>> import re>>>
s='<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+"
n"+"ame"+" is  "+"21c";)</script>'>>> *# my version*>>>
start=time();null=s.replace(' +','+').replace('+
','+').replace('+','').replace('"','').replace('(','("').replace(';)','";)');*print*
time()-start2.8133392334e-05>>> *# nobody's version*>>> r =
re.compile(r'"\s*\+\s*"')>>> start = time();r.sub('',s);*print*
time()-start3.40938568115e-05>>> *# tiefeng's version*>>>
start=time();re.sub(r'(?<=")(.+)(?=")',
''.join(re.findall(r'"([^"]+)"', s)), s);*print*
time()-start0.000455141067505>>>
3.40938568115e-05/2.8133392334e-051.2118644067781548>>>
0.000455141067505/2.8133392334e-0516.177966101690096>>>
0.000455141067505/3.40938568115e-0513.349650349662966
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/6e464d39/attachment.html>

From darkneter at gmail.com  Tue Jul 28 23:58:53 2009
From: darkneter at gmail.com (NighterNet)
Date: Tue, 28 Jul 2009 20:58:53 -0700 (PDT)
Subject: simple splash screen?
Message-ID: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>

I am trying to make a simple splash screen from python 3.1.Not sure
where to start looking for it. Can any one help?


From hjtoi-better-remove-before-reply at comcast.net  Wed Jul 29 00:16:38 2009
From: hjtoi-better-remove-before-reply at comcast.net (Heikki Toivonen)
Date: Tue, 28 Jul 2009 21:16:38 -0700
Subject: M2Crypto hangs on this URL
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
Message-ID: <h4oif8$5ck$1@aioe.org>

John Nagle wrote:
> There's something strange about this URL:
> 
> "https://sagar310.pontins.com/sraep/"

The following program finishes fine for me using M2Crypto 0.20beta1 +
openssl 0.9.8g. Like Martin mentioned in another message, maybe someone
fixed the site.

from M2Crypto import SSL
ctx = SSL.Context()
# If you comment out the next 2 lines, the connection won't be secure
#ctx.set_verify(SSL.verify_peer | SSL.verify_fail_if_no_peer_cert, depth=9)
#if ctx.load_verify_locations('ca.pem') != 1: raise Exception('No CA certs')
c = SSL.Connection(ctx)
c.connect(('sagar310.pontins.com', 443))
c.send('GET /sraep/ \n')
c.close()

-- 
  Heikki Toivonen - http://heikkitoivonen.net


From dearmanzur at gmail.com  Wed Jul 29 00:35:44 2009
From: dearmanzur at gmail.com (Manzur Ahmed)
Date: Wed, 29 Jul 2009 00:35:44 -0400
Subject: need help using Tkinter
In-Reply-To: <op.uxsyk5owfvx12t@jerzozwiesz.home.aster.pl>
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
	<op.uxsyk5owfvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <60972b200907282135s7fd125b4h5dc118a60027ff64@mail.gmail.com>

i figured it out.  its actually because i'm using python 3.1.  for python
3.0+, many of the packages are lowercased, tkinter being one of them and so
thats why i wan getting a module not found error . . .  thanks for getting
back to me.

manzur

On Tue, Jul 28, 2009 at 8:06 PM, Jan Kaliszewski <zuo at chopin.edu.pl> wrote:

> 28-07-2009 o 17:17 Manzur Ahmed <dearmanzur at gmail.com> wrote:
>
> i wanted to ask you if one of you could help me to use Tkinter. i'm trying
>> to just create a simple GUI for which I have provided the code for below.
>>
> [snip]
>
>> i tried to google search this and there were some threads that were saying
>> to install tcl but that does not work. I did check the Lib directory under
>> the Python directory and I did not see a Tkinter module anywhere which I
>> think is the problem. Do you know how I would go about with getting this
>> module and if that is not the problem or if you think it might be caused
>> by
>> something else, can you please give me some guidance?
>>
>
> What operating system do you use?
>
> *j
>
> --
> Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/36b5a563/attachment.html>

From gagsl-py2 at yahoo.com.ar  Wed Jul 29 02:08:19 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 29 Jul 2009 03:08:19 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3812.1248748204.8015.python-list@python.org>
	<027ed9be$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <op.uxtfb500x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 09:02:40 -0300, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> escribi?:
> On Mon, 27 Jul 2009 23:16:39 -0300, Gabriel Genellina wrote:
>
>> I don't see the point on "fixing" either the Python script or httplib to
>> accomodate for an invalid server certificate... If it's just for
>> internal testing, I'd use HTTP instead (at least until the certificate
>> is fixed).
>
> In real life, sometimes you need to drive with bad brakes on your car,
> walk down dark alleys in the bad part of town, climb a tree without a
> safety line, and use a hammer without wearing goggles. We can do all
> these things.
>
> The OP has said that, for whatever reason, he needs to ignore a bad
> server certificate when connecting to HTTPS. Python is a language where
> developers are allowed to shoot themselves in the foot, so long as they
> do so in full knowledge of what they're doing.
>
> So, putting aside all the millions of reasons why the OP shouldn't accept
> an invalid certificate, how can he accept an invalid certificate?

Yes, I understand the situation, but I'm afraid there is no way (that I  
know of). At least not without patching _ssl.c; all the SSL negotiation is  
handled by the OpenSSL library itself.

I vaguely remember a pure Python SSL implementation somewhere that perhaps  
could be hacked to bypass all controls. But making it work properly will  
probably require a lot more effort than installing a self signed  
certificate in the server...

-- 
Gabriel Genellina



From jayshree06comp at gmail.com  Wed Jul 29 02:58:36 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Tue, 28 Jul 2009 23:58:36 -0700 (PDT)
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
	<cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>
	<7d5brmF2a1alcU1@mid.uni-berlin.de>
Message-ID: <2b5b00b8-f9ba-4d16-b950-681aa6fa010a@24g2000yqm.googlegroups.com>

On Jul 27, 2:55?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> jayshree wrote:
> > On Jul 27, 1:09?pm, Kushal Kumaran <kushal.kumaran+pyt... at gmail.com>
> > wrote:
> >> On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06c... at gmail.com>
> >> wrote:
> >> > pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>
> >> > Please tell me how to open a file placed in any directory or in same
> >> > directory.
>
> >> > After opening this file i want to use the contain (public key ) for
> >> > encryption
>
> >> Does the code you've put into your message not read that file? ?If you
> >> get an exception, copy-paste in the traceback message you get into
> >> your mail.
>
> >> --
> >> kushal
>
> > ? ? try:
> > ? ? ? ? pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
> > ? ? except IOError:
> > ? ? ? ? print "Error: can\'t find file or read data"
> > ? ? else:
> > ? ? ? ? print "reading from file successfully"
>
> >>Still no error it gives .what to do?
>
> Erm - so it doesn't give an error - which means you have successfully opened
> a file, and read it's contents.
>
> So what exactly is your problem?
>
> Diez- Hide quoted text -
>
> - Show quoted text -

> The Exact Problem is how to use the key containing by .pem file for 'encryption' .
>can i print the contents of the .pem file

see http://stackoverflow.com/questions/1176864/problem-with-the-pem-file


From gagsl-py2 at yahoo.com.ar  Wed Jul 29 02:58:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 29 Jul 2009 03:58:39 -0300
Subject: "Deprecated sets module" with Python 2.6
References: <4A6F5F59.4080507@it.uu.se>
Message-ID: <op.uxthn1wdx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 17:28:09 -0300, Virgil Stokes <vs at it.uu.se> escribi?:

> I would appreciate help on correcting a problem when trying to create an  
> *.exe file using py2exe via GUI2exe with Python 2.6.2.
>
> When using GUI2exe to create an *.exe I always get the following warning  
> during the compile process:
>
>  C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>  DeprecationWarning: the sets module is deprecated
>  import sets

Note that build_exe.py is part of the py2exe package - the warning says  
that py2exe itself is importing a deprecated module, it's not in your code.

> and this results in the creation of an *.exe file that can not be  
> executed.

I don't think the warning above is related to your problem. Are you using  
the latest py2exe version?
You may get more help in the py2exe mailing list; see  
http://www.py2exe.org/

-- 
Gabriel Genellina



From huangchonggnu at gmail.com  Wed Jul 29 03:29:35 2009
From: huangchonggnu at gmail.com (hch)
Date: Wed, 29 Jul 2009 15:29:35 +0800
Subject: No subject
Message-ID: <cb49ae490907290029l4cfa5365o35e038aff9f79cfd@mail.gmail.com>

Hi, everyone

Is there a python script can get a list of how much stack space each
function in your program uses? ( the program is compiled by gcc)

Any advice will be appreciate.


From vs at it.uu.se  Wed Jul 29 03:46:50 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Wed, 29 Jul 2009 09:46:50 +0200
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <7d99s9F28m0aaU1@mid.uni-berlin.de>
References: <mailman.3856.1248812897.8015.python-list@python.org>
	<7d99s9F28m0aaU1@mid.uni-berlin.de>
Message-ID: <4A6FFE6A.8060503@it.uu.se>

Diez B. Roggisch wrote:
> Virgil Stokes schrieb:
>> I would appreciate help on correcting a problem when trying to create 
>> an *.exe file using py2exe via GUI2exe with Python 2.6.2.
>>
>> When using GUI2exe to create an *.exe I always get the following 
>> warning during the compile process:
>>
>> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>> DeprecationWarning: the sets module is deprecated
>> import sets
>>
>> and this results in the creation of an *.exe file that can not be 
>> executed.
>>
>> On the other hand, if I use the same procedure (on the same Python 
>> code) with
>> Python 2.5, there are no warnings and the *.exe works fine.
>>
>> The procedure used is that given in the example "Less simpler one" at
>>
>>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
>>
>> Any suggestions, help, ... would be greatly appreciated.
>
> If you don't need your app running on python2.3 and earlier, just 
> remove the sets-module and replace it with the builtin "set".
Of course Diez, this is a good suggestion. However, in this case the 
Python code that I am trying to convert into an *.exe file does not 
refer to sets directly; i.e, the use of this module is buried within a 
package that is imported (wxPython) which is not under my control.

--V
>
> Diez




From huangchonggnu at gmail.com  Wed Jul 29 03:51:26 2009
From: huangchonggnu at gmail.com (hch)
Date: Wed, 29 Jul 2009 15:51:26 +0800
Subject: about analyze object's stack usage
Message-ID: <cb49ae490907290051gd1678a7yc8d82dd29c53a367@mail.gmail.com>

Hi, everyone

Is there a python script can get a list of how much stack space each
function in your program uses? ( the program is compiled by gcc)

Any advice will be appreciate.


From vs at it.uu.se  Wed Jul 29 03:52:57 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Wed, 29 Jul 2009 09:52:57 +0200
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <4A6FFE6A.8060503@it.uu.se>
References: <mailman.3856.1248812897.8015.python-list@python.org>	<7d99s9F28m0aaU1@mid.uni-berlin.de>
	<4A6FFE6A.8060503@it.uu.se>
Message-ID: <4A6FFFD9.4050508@it.uu.se>

Virgil Stokes wrote:
> Diez B. Roggisch wrote:
>> Virgil Stokes schrieb:
>>> I would appreciate help on correcting a problem when trying to 
>>> create an *.exe file using py2exe via GUI2exe with Python 2.6.2.
>>>
>>> When using GUI2exe to create an *.exe I always get the following 
>>> warning during the compile process:
>>>
>>> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>>> DeprecationWarning: the sets module is deprecated
>>> import sets
>>>
>>> and this results in the creation of an *.exe file that can not be 
>>> executed.
>>>
>>> On the other hand, if I use the same procedure (on the same Python 
>>> code) with
>>> Python 2.5, there are no warnings and the *.exe works fine.
>>>
>>> The procedure used is that given in the example "Less simpler one" at
>>>
>>>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
>>>
>>> Any suggestions, help, ... would be greatly appreciated.
>>
>> If you don't need your app running on python2.3 and earlier, just 
>> remove the sets-module and replace it with the builtin "set".
> Of course Diez, this is a good suggestion. However, in this case the 
> Python code that I am trying to convert into an *.exe file does not 
> refer to sets directly; i.e, the use of this module is buried within a 
> package that is imported (wxPython) which is not under my control.
>
> --V
>>
>> Diez
>
>
Whoops, the reference to the module sets is in py2exe not wxPython.

--V



From hendrik at microcorp.co.za  Wed Jul 29 04:08:24 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 29 Jul 2009 10:08:24 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4A6F1506.9030207@mrabarnett.plus.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<200907281035.48713.hendrik@microcorp.co.za>
	<4A6F1506.9030207@mrabarnett.plus.com>
Message-ID: <200907291008.24572.hendrik@microcorp.co.za>

On Tuesday 28 July 2009 17:11:02 MRAB wrote:

> If you were a "COBOL" programmer, would you want to shout about it? :-)

Hey don't knock it! - at the time, it was either COBOL or FORTRAN
or some assembler or coding in hex or octal.

And if code is data, where is Pythons ALTER statement?

*Ducks*

:-)    Hendrik






From milesck at umich.edu  Wed Jul 29 04:14:03 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 29 Jul 2009 01:14:03 -0700
Subject: python 3 and stringio.seek
In-Reply-To: <h4mui9$q1o$1@nnrp-beta.newsland.it>
References: <h4mui9$q1o$1@nnrp-beta.newsland.it>
Message-ID: <ECDBC5EB-B60D-4F54-81A8-9989C33AA70C@umich.edu>


On Jul 28, 2009, at 6:30 AM, Michele Petrazzo wrote:

> Hi list,
> I'm trying to port a my library to python 3, but I have a problem  
> with a
> the stringio.seek:
> the method not accept anymore a value like pos=-6 mode=1, but the  
> "old"
> (2.X) version yes...
>
> The error:
>  File "/home/devel/Py3/lib/python3.0/io.py", line 2031, in seek
>    return self._seek(pos, whence)
> IOError: Can't do nonzero cur-relative seeks
>
>
> How solve this?

In Python 2, StringIO is a stream of bytes (non-Unicode characters).   
In Python 3, StringIO is a stream of text (Unicode characters).  In  
the early development of Python 3 (and 3.1's _pyio), it was  
implemented as a TextIOWrapper over a BytesIO buffer.  TextIOWrapper  
does not support relative seeks because it is difficult to map the  
concept of a "current position" between bytes and the text that it  
encodes, especially with variable-width encodings and other  
considerations.  Furthermore, the value returned from  
TextIOWrapper.tell isn't just a file position but a "cookie" that  
contains other data necessary to restore the decoding mechanism to the  
same state.  However, for the default encoding (utf-8), the current  
position is equivalent to that of the underlying bytes buffer.

In Python 3, StringIO is implemented using an internal buffer of  
Unicode characters.  There is no technical reason why it can't support  
relative seeks; I assume it does not for compatibility with the  
original Python TextIOWrapper implementation (which is present in  
3.1's _pyio, but not in 3.0).

Note that because of the different implementations, StringIO.tell()  
(and seek) behaves differently for the C and Python implementations:

$ python3.1
 >>> import io, _pyio
 >>> s = io.StringIO('\u263A'); s.read(1), s.tell()
('?', 1)
 >>> s = _pyio.StringIO('\u263A'); s.read(1), s.tell()
('?', 3)

The end result seems to be that, for text streams (including  
StreamIO), you *should* treat the value returned by tell() as an  
opaque magic cookie, and *only* pass values to seek() that you have  
obtained from a previous tell() call.  However, in practice, it  
appears that you *may* seek StringIO objects relatively by characters  
using s.seek(s.tell() + n), so long as you do not use the  
_pyio.StringIO implementation.

If what you actually want is a stream of bytes, use BytesIO, which may  
be seeked (sought?) however you please.

I'm basing this all on my reading of the Python source (and svn  
history), since it doesn't seem to be documented, so take it with a  
grain of salt.

-Miles



From gregor.thalhammer at gmail.com  Wed Jul 29 04:14:31 2009
From: gregor.thalhammer at gmail.com (gregorth)
Date: Wed, 29 Jul 2009 01:14:31 -0700 (PDT)
Subject: fast video encoding
Message-ID: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>

Hi all,

for a scientific application I need to save a video stream to disc for
further post processing. My cam can deliver 8bit grayscale images with
resolution 640x480 with a framerate up to 100Hz, this is a data rate
of 30MB/s. Writing the data uncompressed to disc hits the data
transfer limits of my current system and creates huge files. Therefore
I would like to use video compression, preferably fast and high
quality to lossless encoding. Final file size is not that important.
Because of the hardware I am bound to WinXP.

I already tried pymedia for encoding to mpeg2, however I only managed
to get a framerate of about 30-40fps (on a 1.8GHz dual core). There is
still room for improvements in my code, but before trying hard I want
to ask for advices or other possibilities. I also found gstreamer with
pygst python bindings, which seems to be more modern (and performant?)
package than pymedia. I did not yet try it, especially since I didn't
find a simple code example of how to use it for my use case. Can
somebody give me a hint?

I also found huffyuv or lagarith which is provided as a directshow
codec for Windows. Can somebody give me a hint how to use a directshow
codec with python?

I am a novice with video encoding. I found that few codecs support
gray scale images. Any hints to take advantage of the fact that I only
have gray scale images?

Thanks for any help

Gregor



From __peter__ at web.de  Wed Jul 29 04:21:05 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 29 Jul 2009 10:21:05 +0200
Subject: instead of depending on data = array('h') .. write samples 1 by 1
	to w = wave.open("wav.wav", "w")
References: <mailman.3855.1248811181.8015.python-list@python.org>
Message-ID: <h4p0p8$l9k$01$1@news.t-online.com>

'2+ wrote:

> it says
> Wave_write.writeframes(data)
> will that mean
> "from array import array"
> is a must?
> 
> this does the job:
> 
> import oil
> import wave
> from array import array
> 
> a = oil.Sa()
> 
> w = wave.open("current.wav", "w")
> w.setnchannels(2)
> w.setsampwidth(2)
> w.setframerate(44100)
> 
> data = array('h')
> 
> for gas in range(44100 * 5):
>     a.breath()
>     r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>     l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>     data.append(r)
>     data.append(l)
> 
> w.writeframes(data.tostring())
> w.close()
> 
> don't like array becoming so huge so tested this and it was also okay:
> 
> for gas in range(44100 * 5):
>     a.breath()
>     data = array('h')
>     r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>     l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>     data.append(r)
>     data.append(l)
>     w.writeframes(data.tostring())
> 
> but without array .. it becomes 15secs(3 times longer than was
> intended to be) of wav file:
> 
> for gas in range(44100 * 5):
>     a.breath()
>     r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>     l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>     w.writeframes(hex(r))
>     w.writeframes(hex(l))

Doesn't it sound strange, too? You are writing bogus bytes to the file. 
Compare:
 
>>> import array
>>> array.array("h", [42]).tostring()
'*\x00'
>>> hex(42)
'0x2a'

Not only do they differ in length, the contents are different, too. If 
you're unfamiliar with string escape codes, here's a way to see the bytes:

>>> map(ord, array.array("h", [42]).tostring())
[42, 0]
>>> map(ord, hex(42))
[48, 120, 50, 97]

> should i just be happy with depennding on using array?
> or is there a solution to make the last one work properly?

There is a way to make the last one work: use struct.pack("h", r) instead of 
hex(r). I'm of course assuming that the first version does give you the 
desired result. You should not continue before you have verified that.

I still recommend array for performance reasons. If memory usage is an issue 
you can adopt a hybrid approach:

# untested
from itertools import islice
from array import array

def gen_data():
    for gas in xrange(44100 * 5): # range --> xrange
        a.breath()
        r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
        l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
        yield r
        yield l

data = gen_data()
N = 2**20
while True:
    chunk = array('h')
    chunk.extend(islice(data, N))
    if not chunk:
        break
    w.writeframes(chunk.tostring())

This will limit the array size to 4N bytes.

Peter



From michael at stroeder.com  Wed Jul 29 04:45:05 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Wed, 29 Jul 2009 10:45:05 +0200
Subject: 64-bit issues with dictionaries in Python 2.6
Message-ID: <hpe5k6-ed5.ln1@nb2.stroeder.com>

HI!

Are there any known issues with dictionaries in Python 2.6 (not 2.6.2)
when running on a 64-bit platform?

A friend of mine experiences various strange problems with my web2ldap
running with Python 2.6 shipped with openSUSE 11.1 x64. For me it seems
some dictionary-based internal registries of web2ldap are not working.
Yes, the next test would be to compile Python 2.6.2 from source...

Any hint is appreciated.

Ciao, Michael.


From user at example.net  Wed Jul 29 05:02:25 2009
From: user at example.net (superpollo)
Date: Wed, 29 Jul 2009 11:02:25 +0200
Subject: idiom for list looping
Message-ID: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>

hi clp.

i want to get from here:

nomi = ["one", "two", "three"]

to here:

0 - one
1 - two
2 - three

i found two ways:

first way:

for i in range(len(nomi)):
     print i, "-", nomi[i]

or second way:

for (i, e) in enumerate(nomi):
     print i, "-", e

which one is "better"? is there a more pythonic way to do it?

bye

ps:

max2 at 192.168.1.102:~/test$ python -V
Python 2.3.4
max2 at 192.168.1.102:~/test$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
max2 at 192.168.1.102:~/test$


From d at vidr.cc  Wed Jul 29 05:31:47 2009
From: d at vidr.cc (David Roberts)
Date: Wed, 29 Jul 2009 19:31:47 +1000
Subject: idiom for list looping
In-Reply-To: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
Message-ID: <fe0877110907290231u33c567c9kf13210a544af1282@mail.gmail.com>

To the best of my knowledge the second way is more pythonic - the
first is a little too reminiscent of C. A couple of notes:
- you don't need the parentheses around "i, e"
- if you were going to use the first way it's better to use xrange
instead of range for iteration

--
David Roberts
http://da.vidr.cc/



On Wed, Jul 29, 2009 at 19:02, superpollo<user at example.net> wrote:
> hi clp.
>
> i want to get from here:
>
> nomi = ["one", "two", "three"]
>
> to here:
>
> 0 - one
> 1 - two
> 2 - three
>
> i found two ways:
>
> first way:
>
> for i in range(len(nomi)):
> ? ?print i, "-", nomi[i]
>
> or second way:
>
> for (i, e) in enumerate(nomi):
> ? ?print i, "-", e
>
> which one is "better"? is there a more pythonic way to do it?
>
> bye
>
> ps:
>
> max2 at 192.168.1.102:~/test$ python -V
> Python 2.3.4
> max2 at 192.168.1.102:~/test$ uname -a
> Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
> max2 at 192.168.1.102:~/test$
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From python at mrabarnett.plus.com  Wed Jul 29 05:38:29 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 10:38:29 +0100
Subject: idiom for list looping
In-Reply-To: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
Message-ID: <4A701895.5000003@mrabarnett.plus.com>

superpollo wrote:
> hi clp.
> 
> i want to get from here:
> 
> nomi = ["one", "two", "three"]
> 
> to here:
> 
> 0 - one
> 1 - two
> 2 - three
> 
> i found two ways:
> 
> first way:
> 
> for i in range(len(nomi)):
>     print i, "-", nomi[i]
> 
> or second way:
> 
> for (i, e) in enumerate(nomi):
>     print i, "-", e
> 
> which one is "better"? is there a more pythonic way to do it?
> 
'enumerate' is the Pythonic solution.


From gnewsg at gmail.com  Wed Jul 29 06:25:19 2009
From: gnewsg at gmail.com (Giampaolo Rodola')
Date: Wed, 29 Jul 2009 03:25:19 -0700 (PDT)
Subject: "Deprecated sets module" with Python 2.6
References: <4A6F5F59.4080507@it.uu.se>
	<mailman.3874.1248850703.8015.python-list@python.org>
Message-ID: <d16dc2eb-e18e-4906-833a-e42806bc28f4@c1g2000yqi.googlegroups.com>

What about this?

import warnings
warnings.simplefilter('ignore', DeprecationWarning)
import the_module_causing_the_warning
warnings.resetwarnings()


--- Giampaolo
http://code.google.com/p/pyftpdlib
http://code.google.com/p/psutil


From contact at xavierho.com  Wed Jul 29 06:37:44 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 20:37:44 +1000
Subject: idiom for list looping
In-Reply-To: <4A701895.5000003@mrabarnett.plus.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
Message-ID: <2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>

>
> superpollo wrote:
>
>>
>> for (i, e) in enumerate(nomi):
>>    print i, "-", e
>>
>> Just to be random:

print '\n'.join(["%s - %s" % (i, e) for i, e in enumerate(nomi)])

This has one advantage: only print once. So it's slightly faster if you have
a list of a large amount.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/aa3e26bb/attachment.html>

From python at mrabarnett.plus.com  Wed Jul 29 06:52:08 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 11:52:08 +0100
Subject: idiom for list looping
In-Reply-To: <2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
Message-ID: <4A7029D8.3010700@mrabarnett.plus.com>

Xavier Ho wrote:
>     superpollo wrote:
> 
> 
>         for (i, e) in enumerate(nomi):
>            print i, "-", e
> 
> Just to be random:
> 
> print '\n'.join(["%s - %s" % (i, e) for i, e in enumerate(nomi)])
> 
> This has one advantage: only print once. So it's slightly faster if you 
> have a list of a large amount.
> 
Slightly shorter:

print '\n'.join("%s - %s" % p for p in enumerate(nomi))

:-)


From contact at xavierho.com  Wed Jul 29 07:00:37 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 21:00:37 +1000
Subject: idiom for list looping
In-Reply-To: <4A7029D8.3010700@mrabarnett.plus.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<4A7029D8.3010700@mrabarnett.plus.com>
Message-ID: <2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>

On Wed, Jul 29, 2009 at 8:52 PM, MRAB <python at mrabarnett.plus.com> wrote:

> Slightly shorter:
>
> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
>
> :-)
>
That's cool. Does that make the "list" a tuple? (not that it matters, I'm
just curious!)

I just tested for a list of 1000 elements (number in letters from 1 to 1000
code I wrote for doing project euler problem 17), and the join method is 0.1
seconds faster than the for loop! Woo!? ;p
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/41513f45/attachment.html>

From user at example.net  Wed Jul 29 07:02:14 2009
From: user at example.net (superpollo)
Date: Wed, 29 Jul 2009 13:02:14 +0200
Subject: idiom for list looping
In-Reply-To: <mailman.3884.1248864728.8015.python-list@python.org>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>	<4A701895.5000003@mrabarnett.plus.com>	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<mailman.3884.1248864728.8015.python-list@python.org>
Message-ID: <4a702c37$0$34617$4fafbaef@reader4.news.tin.it>

MRAB wrote:
> Xavier Ho wrote:
> 
>>     superpollo wrote:
>>
>>
>>         for (i, e) in enumerate(nomi):
>>            print i, "-", e
>>
>> Just to be random:
>>
>> print '\n'.join(["%s - %s" % (i, e) for i, e in enumerate(nomi)])
>>
>> This has one advantage: only print once. So it's slightly faster if 
>> you have a list of a large amount.
>>
> Slightly shorter:
> 
> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
> 
> :-)

 >>> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
   File "<stdin>", line 1
     print '\n'.join("%s - %s" % p for p in enumerate(nomi))
                                     ^
SyntaxError: invalid syntax
 >>> print '\n'.join(["%s - %s" % p for p in enumerate(nomi)])
0 - one
1 - two
2 - three
 >>> help()

Welcome to Python 2.3!  This is the online help utility.
...
 >>>

;-)

bye


From contact at xavierho.com  Wed Jul 29 07:16:41 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 21:16:41 +1000
Subject: idiom for list looping
In-Reply-To: <2d56febf0907290416x75d2edb3i88ad452ba18894f1@mail.gmail.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<mailman.3884.1248864728.8015.python-list@python.org>
	<4a702c37$0$34617$4fafbaef@reader4.news.tin.it>
	<2d56febf0907290416x75d2edb3i88ad452ba18894f1@mail.gmail.com>
Message-ID: <2d56febf0907290416x389a1b72w64f583d1d229bbf9@mail.gmail.com>

Ack, sent to the wrong email again.

On Wed, Jul 29, 2009 at 9:02 PM, superpollo <user at example.net> wrote:

>
> >>> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
>  File "<stdin>", line 1
>    print '\n'.join("%s - %s" % p for p in enumerate(nomi))
>                                    ^
> SyntaxError: invalid syntax


lol, I knew I shouldn't have trusted untested code!


> >>> print '\n'.join(["%s - %s" % p for p in enumerate(nomi)])
> 0 - one
> 1 - two
> 2 - three
>

Yup.. but using a variable for the tuple itself was a good move though =P.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/d828df45/attachment.html>

From python at mrabarnett.plus.com  Wed Jul 29 07:17:14 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 12:17:14 +0100
Subject: idiom for list looping
In-Reply-To: <2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>	<4A701895.5000003@mrabarnett.plus.com>	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>	<4A7029D8.3010700@mrabarnett.plus.com>
	<2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>
Message-ID: <4A702FBA.8060303@mrabarnett.plus.com>

Xavier Ho wrote:
> On Wed, Jul 29, 2009 at 8:52 PM, MRAB <python at mrabarnett.plus.com 
> <mailto:python at mrabarnett.plus.com>> wrote:
> 
>     Slightly shorter:
> 
>     print '\n'.join("%s - %s" % p for p in enumerate(nomi))
> 
>     :-)
> 
> That's cool. Does that make the "list" a tuple? (not that it matters, 
> I'm just curious!)
> 
I've just replaced the list comprehension with a generator expression.



From contact at xavierho.com  Wed Jul 29 07:20:50 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 21:20:50 +1000
Subject: idiom for list looping
In-Reply-To: <4A702FBA.8060303@mrabarnett.plus.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<4A7029D8.3010700@mrabarnett.plus.com>
	<2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>
	<4A702FBA.8060303@mrabarnett.plus.com>
Message-ID: <2d56febf0907290420m7543ee8bs3c6ad9914fb51d39@mail.gmail.com>

On Wed, Jul 29, 2009 at 9:17 PM, MRAB <python at mrabarnett.plus.com> wrote:


> I've just replaced the list comprehension with a generator expression.
>
>
Oh, and that isn't in Python 2.3.... I see. Generators are slightly newer,
eh.

Thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/59b37fb2/attachment.html>

From nick at craig-wood.com  Wed Jul 29 07:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Wed, 29 Jul 2009 06:29:56 -0500
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <slrnh70a5q.d1m.nick@irishsea.home.craig-wood.com>

John D Giotta <jdgiotta at gmail.com> wrote:
>  I'm looking to run a process with a limit of 3 instances, but each
>  execution is over a crontab interval. I've been investigating the
>  threading module and using daemons to limit active thread objects, but
>  I'm not very successful at grasping the documentation.
> 
>  Is it possible to do what I'm trying to do and if so anyone know of a
>  useful example to get started?

If you want a simple, cross platform way of doing it, then bind each
process to a different local tcp port.

Make a list of 3 ports, and try binding to each port in turn.  If you
can't find a port to bind to then there are already 3 instances
running.

Something like this

import socket
PORTS = range(10000,10003)
lock_sock = None

def lock_process(_locks = []):
    for port in PORTS:
        sock = socket.socket()
        try:
            sock.bind(("localhost", port))
        except socket.error, e:
            sock = None
        else:
            _locks.append(sock)
            break
    else:
        raise Exception("Too many instances of me running")

for i in range(5):
    print "Trying",i+1
    lock_process()


Which prints

Trying 1
Trying 2
Trying 3
Trying 4
Traceback (most recent call last):
  File "<stdin>", line 20, in <module>
  File "<stdin>", line 16, in lock_process
Exception: Too many instances of me running

You could do the same thing with lock files also very easily...


-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From spookyk at gmail.com  Wed Jul 29 07:35:42 2009
From: spookyk at gmail.com (Rincewind)
Date: Wed, 29 Jul 2009 04:35:42 -0700 (PDT)
Subject: QFileDialog setFileMode blues
Message-ID: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>

Heya,

I am fairly new to Python and even newer to Qt.
The problem is opening a Qt file dialog to select folders only.
QFileDialog has a nice and dandy setFileMode() function just for that.
The only trouble is that I cannot make it work.
Last thing I've tried was something like this:

        self.fd = QtGui.QFileDialog()
        self.fd.setFileMode(self.fd.FileMode(4))
        filename = self.fd.getOpenFileName()

..but it was fruitless.

Any help? Tons of internets in return!


From Ron.Barak at lsi.com  Wed Jul 29 07:36:05 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Wed, 29 Jul 2009 12:36:05 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <mailman.44.1248861603.12188.python-list@python.org>
References: <mailman.44.1248861603.12188.python-list@python.org>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>


Hi,

I wanted to make a python byte-code file executable, expecting to be able to run it without specifying "python" on the (Linux bash) command line.

So, I wrote the following:

[root at VMLinux1 python]# cat test_pyc.py
#!/usr/bin/env python

print "hello"
[root at VMLinux1 python]#

and made its pyc file executable:

[root at VMLinux1 python]# ls -ls test_pyc.pyc
4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
[root at VMLinux1 python]#

So, I see:

[root at VMLinux1 python]# file test_pyc.py*
test_pyc.py:  a python script text executable
test_pyc.pyc: python 2.3 byte-compiled
[root at VMLinux1 python]#

If I try to do the following, no problem:

[root at VMLinux1 python]# python test_pyc.pyc
hello
[root at VMLinux1 python]#

However, the following fails:

[root at VMLinux1 python]# ./test_pyc.pyc
-bash: ./test_pyc.pyc: cannot execute binary file
[root at VMLinux1 python]#

Is there a way to run a pyc file without specifying the python path ?

Bye,
Ron.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/a6d3b02a/attachment.html>

From phil at riverbankcomputing.com  Wed Jul 29 07:45:03 2009
From: phil at riverbankcomputing.com (Phil Thompson)
Date: Wed, 29 Jul 2009 12:45:03 +0100
Subject: QFileDialog setFileMode blues
In-Reply-To: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>
References: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>
Message-ID: <8477fc1d11b68f7e3e11237d957890b1@localhost>

On Wed, 29 Jul 2009 04:35:42 -0700 (PDT), Rincewind <spookyk at gmail.com>
wrote:
> Heya,
> 
> I am fairly new to Python and even newer to Qt.
> The problem is opening a Qt file dialog to select folders only.
> QFileDialog has a nice and dandy setFileMode() function just for that.
> The only trouble is that I cannot make it work.
> Last thing I've tried was something like this:
> 
>         self.fd = QtGui.QFileDialog()
>         self.fd.setFileMode(self.fd.FileMode(4))
>         filename = self.fd.getOpenFileName()
> 
> ..but it was fruitless.
> 
> Any help? Tons of internets in return!

QFileDialog.getOpenFileName() is a static method that creates its own
QFileDialog internally. It's not using the one you have created and
configured.

Phil


From marcusw at cox.net  Wed Jul 29 08:23:14 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 08:23:14 -0400
Subject: fast video encoding
In-Reply-To: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
References: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
Message-ID: <h4pevi$1bqt$1@adenine.netfront.net>

On 7/29/2009 4:14 AM, gregorth wrote:
> Hi all,
> 
> for a scientific application I need to save a video stream to disc for
> further post processing. My cam can deliver 8bit grayscale images with
> resolution 640x480 with a framerate up to 100Hz, this is a data rate
> of 30MB/s. Writing the data uncompressed to disc hits the data
> transfer limits of my current system and creates huge files. Therefore
> I would like to use video compression, preferably fast and high
> quality to lossless encoding. Final file size is not that important.
Try googling realtime greyscale video codec...
> Because of the hardware I am bound to WinXP.
There's always a way to run linux :p
> 
> I already tried pymedia for encoding to mpeg2, however I only managed
> to get a framerate of about 30-40fps (on a 1.8GHz dual core). There is
> still room for improvements in my code, but before trying hard I want
> to ask for advices or other possibilities. I also found gstreamer with
> pygst python bindings, which seems to be more modern (and performant?)
> package than pymedia. I did not yet try it, especially since I didn't
> find a simple code example of how to use it for my use case. Can
> somebody give me a hint?
Video encoding is not my specialty, but my recommendation here is to 
drop python because of its slow speed and work in c as much as possible.
> 
> I also found huffyuv or lagarith which is provided as a directshow
> codec for Windows. Can somebody give me a hint how to use a directshow
> codec with python?
Not me, sorry :(
Never worked directly with directshow (no pun intended).
> 
> I am a novice with video encoding. I found that few codecs support
> gray scale images. Any hints to take advantage of the fact that I only
> have gray scale images?
Greyscale PNG or BMP compression.
> 
> Thanks for any help
Don't know if this counts as help, but you're welcome!
> 
> Gregor
> 
Marcus


From marcusw at cox.net  Wed Jul 29 08:24:33 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 08:24:33 -0400
Subject: simple splash screen?
In-Reply-To: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
Message-ID: <h4pf23$1bqt$2@adenine.netfront.net>

On 7/28/2009 11:58 PM, NighterNet wrote:
> I am trying to make a simple splash screen from python 3.1.Not sure
> where to start looking for it. Can any one help?
Trying to make a splash screen for python?
Or trying to do image processing in python?

Marcus


From sibtey.mehndi at genpact.com  Wed Jul 29 08:25:22 2009
From: sibtey.mehndi at genpact.com (Mehndi, Sibtey)
Date: Wed, 29 Jul 2009 05:25:22 -0700
Subject: how to embed the python interpreter into web App
Message-ID: <1A343A98C8DAE44A8D9D1BF310F90D5E023D54C3@GCPWINGGN2EVS11.IND.CORP.AD>

Hi All
I am trying to embed the python interpreter in to a web app but could not get the way, any one can suggest me how to do this.

Thanks,
Sibtey Mehdi


This e-mail (and any attachments), is confidential and may be privileged. It may be read, copied and used only
by intended recipients. Unauthorized access to this e-mail (or attachments) and disclosure or copying of its 
contents or any action taken in reliance on it is unlawful. Unintended recipients must notify the sender immediately 
by e-mail/phone & delete it from their system without making any copies or disclosing it to a third person.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/ed6d98b5/attachment.html>

From duncan.booth at invalid.invalid  Wed Jul 29 08:26:11 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 29 Jul 2009 12:26:11 GMT
Subject: Need help in passing a "-c command" argument to the interactive
	shell.
References: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
Message-ID: <Xns9C5788AE7C466duncanbooth@127.0.0.1>

Bill <bsagert at gmail.com> wrote:

> On my windows box I type => c:\x>python -c "import re"
> 
> The result is => c:\x>
> 
> In other words, the Python interactive shell doesn't even open. What
> am I doing wrong?
> 
> I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
> argument passing, but to no avail.

Why are you reading documentation for Python 1.5? There have been just a 
few releases since then.

Try reading http://docs.python.org/using/cmdline.html instead, specifically 
the part about the -i command line option. Or you could just try "python 
-?" at a command prompt.

-- 
Duncan Booth http://kupuguy.blogspot.com


From marcusw at cox.net  Wed Jul 29 08:34:09 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 08:34:09 -0400
Subject: about analyze object's stack usage
In-Reply-To: <mailman.3877.1248853887.8015.python-list@python.org>
References: <mailman.3877.1248853887.8015.python-list@python.org>
Message-ID: <h4pfke$1bqt$3@adenine.netfront.net>

On 7/29/2009 3:51 AM, hch wrote:
> Is there a python script can get a list of how much stack space each
> function in your program uses?
I don't think so.
You could try raw reading of the memory from another thread using ctypes
and pointers, but that would be madness.
> ( the program is compiled by gcc)
If you're talking about a c program, almost certainly not. What you 
should do is just use gdb and disas each function and look at what it 
subtracts off of %esp at the third instruction in the function.
I can explain it to you if you are not very experienced in gdb and 
assembly...

Marcus


From rashidsdpk at gmail.com  Wed Jul 29 08:54:24 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Wed, 29 Jul 2009 05:54:24 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <ff376d57-0e81-40cc-866f-ef1b74b10f31@o15g2000yqm.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.more http://0nanotechnology0.blogspot.com/


From catalinfest at gmail.com  Wed Jul 29 09:03:06 2009
From: catalinfest at gmail.com (catalinfest at gmail.com)
Date: Wed, 29 Jul 2009 06:03:06 -0700 (PDT)
Subject: Help with sql and python
Message-ID: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>

Hello !

I have accont on myphpadmin on my server.
I want to create one script in python.
This script manage sql task from my sql server .
How i make this in a simple way ?

Thank you !


From contact at xavierho.com  Wed Jul 29 09:08:12 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 23:08:12 +1000
Subject: Particle research opens door for new technology
In-Reply-To: <ff376d57-0e81-40cc-866f-ef1b74b10f31@o15g2000yqm.googlegroups.com>
References: <ff376d57-0e81-40cc-866f-ef1b74b10f31@o15g2000yqm.googlegroups.com>
Message-ID: <2d56febf0907290608v4fe62d32n804e43008713572b@mail.gmail.com>

Is this a spam? Why did you have to send it 4 times, and it's already in the
past (July 9 and 10) ?

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/53e3e5e3/attachment.html>

From v1d4l0k4 at gmail.com  Wed Jul 29 09:10:47 2009
From: v1d4l0k4 at gmail.com (v1d4l0k4)
Date: Wed, 29 Jul 2009 13:10:47 +0000
Subject: Working with platform.system()
Message-ID: <9a5b5be90907290610t1868ef07p20a5c2bdc3404ab8@mail.gmail.com>

Hi!

I want to know how I can get different expected return values by
platform.system() method. I want to sniff some systems (Linux, Windows, Mac,
BSD, Solaris) and I don't know how I can check them correctly. Could you
give me some expected return values that you know?

Thanks in advance,
Paulo Ricardo
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/5616da8c/attachment.html>

From james at agentultra.com  Wed Jul 29 09:29:55 2009
From: james at agentultra.com (J Kenneth King)
Date: Wed, 29 Jul 2009 09:29:55 -0400
Subject: escaping characters in filenames
Message-ID: <854osv7h2k.fsf@agentultra.com>


I wrote a script to process some files using another program.  One thing
I noticed was that both os.listdir() and os.path.walk() will return
unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
module or recipe that escapes file names and was wondering if anyone
could point me in the right direction.

As an aside, the script is using subprocess.call() with the "shell=True"
parameter.  There isn't really a reason for doing it this way (was just
the fastest way to write it and get a prototype working).  I was
wondering if Popen objects were sensitive to unescaped names like the
shell.  I intend to refactor the function to use Popen objects at some
point and thought perhaps escaping file names may not be entirely
necessary.

Cheers


From nospam at nospam.com  Wed Jul 29 09:55:32 2009
From: nospam at nospam.com (Gilles Ganault)
Date: Wed, 29 Jul 2009 15:55:32 +0200
Subject: Compiling Python for uCLinux appliance?
Message-ID: <7sk075l5p7eq8mek9ooqj5kr0ds10hrvfq@4ax.com>

Hello

I just got a small appliance based on a Blackfin CPU with 64MB RAM and
258MB NAND flash. Using the stock software, there's about 30MB of RAM
left.

Besides C/C++ and shel scripts, I was wondering if it were realistic
to upload a few Python scripts in such a small appliance?

Thank you.


From piet at cs.uu.nl  Wed Jul 29 10:14:45 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 29 Jul 2009 16:14:45 +0200
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
Message-ID: <m2fxcfefu2.fsf@cs.uu.nl>

>>>>> Carl Banks <pavlovevidence at gmail.com> (CB) wrote:

>CB> On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
>>> I'm looking to run a process with a limit of 3 instances, but each
>>> execution is over a crontab interval. I've been investigating the
>>> threading module and using daemons to limit active thread objects, but
>>> I'm not very successful at grasping the documentation.
>>> 
>>> Is it possible to do what I'm trying to do and if so anyone know of a
>>> useful example to get started?

>CB> It seems like you want to limit the number of processes to three; the
>CB> threading module won't help you there because it deals with threads
>CB> within a single process.

>CB> What I'd do is to simply run the system ps to see how many processes
>CB> are running (ps is pretty versatile on most systems and can find
>CB> specifically targeted processes like you program), and exit if there
>CB> are already three.

That will surely run into some race conditions. If the limit of 3
processes is soft then that wouldn't be a big deal, however.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From spookyk at gmail.com  Wed Jul 29 10:15:53 2009
From: spookyk at gmail.com (Rincewind)
Date: Wed, 29 Jul 2009 07:15:53 -0700 (PDT)
Subject: QFileDialog setFileMode blues
References: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>
	<mailman.3889.1248867908.8015.python-list@python.org>
Message-ID: <cce08084-37db-4099-bac1-f76f2a7e6e3b@k1g2000yqf.googlegroups.com>

On Jul 29, 12:45 pm, Phil Thompson <p... at riverbankcomputing.com>
wrote:
> On Wed, 29 Jul 2009 04:35:42 -0700 (PDT), Rincewind <spoo... at gmail.com>
> wrote:
>
> > Heya,
>
> > I am fairly new to Python and even newer to Qt.
> > The problem is opening a Qt file dialog to select folders only.
> > QFileDialog has a nice and dandy setFileMode() function just for that.
> > The only trouble is that I cannot make it work.
> > Last thing I've tried was something like this:
>
> >         self.fd = QtGui.QFileDialog()
> >         self.fd.setFileMode(self.fd.FileMode(4))
> >         filename = self.fd.getOpenFileName()
>
> > ..but it was fruitless.
>
> > Any help? Tons of internets in return!
>
> QFileDialog.getOpenFileName() is a static method that creates its own
> QFileDialog internally. It's not using the one you have created and
> configured.
>
> Phil

You are awesome, thanks!


From python at mrabarnett.plus.com  Wed Jul 29 10:22:34 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 15:22:34 +0100
Subject: escaping characters in filenames
In-Reply-To: <854osv7h2k.fsf@agentultra.com>
References: <854osv7h2k.fsf@agentultra.com>
Message-ID: <4A705B2A.2050807@mrabarnett.plus.com>

J Kenneth King wrote:
> I wrote a script to process some files using another program.  One thing
> I noticed was that both os.listdir() and os.path.walk() will return
> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
> module or recipe that escapes file names and was wondering if anyone
> could point me in the right direction.
> 
That's only necessary if you're building a command line and passing it
as a string.

> As an aside, the script is using subprocess.call() with the "shell=True"
> parameter.  There isn't really a reason for doing it this way (was just
> the fastest way to write it and get a prototype working).  I was
> wondering if Popen objects were sensitive to unescaped names like the
> shell.  I intend to refactor the function to use Popen objects at some
> point and thought perhaps escaping file names may not be entirely
> necessary.
> 
Pass the command line to Popen as a list of strings.


From deets at nospam.web.de  Wed Jul 29 10:46:47 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 29 Jul 2009 16:46:47 +0200
Subject: Compiling Python for uCLinux appliance?
References: <7sk075l5p7eq8mek9ooqj5kr0ds10hrvfq@4ax.com>
Message-ID: <7db5mnF2bf9i2U1@mid.uni-berlin.de>

Gilles Ganault wrote:

> Hello
> 
> I just got a small appliance based on a Blackfin CPU with 64MB RAM and
> 258MB NAND flash. Using the stock software, there's about 30MB of RAM
> left.
> 
> Besides C/C++ and shel scripts, I was wondering if it were realistic
> to upload a few Python scripts in such a small appliance?

Try & check out the gumstix software repo. It comes with python, and thus
some crosscompiling/build-instructions should be in there.

Diez


From jakecjacobson at gmail.com  Wed Jul 29 11:07:34 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Wed, 29 Jul 2009 08:07:34 -0700 (PDT)
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3812.1248748204.8015.python-list@python.org>
	<027ed9be$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3873.1248847683.8015.python-list@python.org>
Message-ID: <fdefad35-b9fe-46c8-8e48-51275e0d9236@h11g2000yqb.googlegroups.com>

On Jul 29, 2:08?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Tue, 28 Jul 2009 09:02:40 -0300, Steven D'Aprano ?
> <st... at remove-this-cybersource.com.au> escribi?:
>
>
>
> > On Mon, 27 Jul 2009 23:16:39 -0300, Gabriel Genellina wrote:
>
> >> I don't see the point on "fixing" either the Python script or httplib to
> >> accomodate for an invalid server certificate... If it's just for
> >> internal testing, I'd use HTTP instead (at least until the certificate
> >> is fixed).
>
> > In real life, sometimes you need to drive with bad brakes on your car,
> > walk down dark alleys in the bad part of town, climb a tree without a
> > safety line, and use a hammer without wearing goggles. We can do all
> > these things.
>
> > The OP has said that, for whatever reason, he needs to ignore a bad
> > server certificate when connecting to HTTPS. Python is a language where
> > developers are allowed to shoot themselves in the foot, so long as they
> > do so in full knowledge of what they're doing.
>
> > So, putting aside all the millions of reasons why the OP shouldn't accept
> > an invalid certificate, how can he accept an invalid certificate?
>
> Yes, I understand the situation, but I'm afraid there is no way (that I ?
> know of). At least not without patching _ssl.c; all the SSL negotiation is ?
> handled by the OpenSSL library itself.
>
> I vaguely remember a pure Python SSL implementation somewhere that perhaps ?
> could be hacked to bypass all controls. But making it work properly will ?
> probably require a lot more effort than installing a self signed ?
> certificate in the server...
>
> --
> Gabriel Genellina

I have it working and I want to thank everyone for their efforts and
very helpful hints.  The error was with me and not understanding the
documentation about the cert_file & key_file.  After using openssl to
divide up my p12 file into a cert file and a key file using the
instructions http://security.ncsa.uiuc.edu/research/grid-howtos/usefulopenssl.php.
I got everything working.

Again, much thanks.

Jake


From darkneter at gmail.com  Wed Jul 29 11:20:45 2009
From: darkneter at gmail.com (NighterNet)
Date: Wed, 29 Jul 2009 08:20:45 -0700 (PDT)
Subject: simple splash screen?
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
	<h4pf23$1bqt$2@adenine.netfront.net>
Message-ID: <68539c2a-e2f6-4956-b779-17d21ca422b1@2g2000prl.googlegroups.com>

On Jul 29, 5:24?am, Marcus Wanner <marc... at cox.net> wrote:
> On 7/28/2009 11:58 PM, NighterNet wrote:> I am trying to make a simple splash screen from python 3.1.Not sure
> > where to start looking for it. Can any one help?
>
> Trying to make a splash screen for python?
> Or trying to do image processing in python?
>
> Marcus

trying to use jpg,gif,png for the splash screen


From wwn1 at sfu.ca  Wed Jul 29 11:24:25 2009
From: wwn1 at sfu.ca (WilsonOfCanada)
Date: Wed, 29 Jul 2009 08:24:25 -0700 (PDT)
Subject: Clearing an array
Message-ID: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>

Hellos,

I was wondering if there is any built-in function that clears the
array.  I was also wondering if this works:

arrMoo = ['33', '342', .... '342']
arrMoo = []


From tutufan at gmail.com  Wed Jul 29 11:24:52 2009
From: tutufan at gmail.com (Mike)
Date: Wed, 29 Jul 2009 08:24:52 -0700 (PDT)
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com>

On Jul 27, 11:34?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> I've been working on a new implementation of the re module.

Fabulous!

If you're extending/changing the interface, there are a couple of sore
points in the current implementation I'd love to see addressed:

- findall/finditer doesn't find overlapping matches.  Sometimes you
really *do* want to know all possible matches, even if they overlap.
This comes up in bioinformatics, for example.

- split won't split on empty patterns, e.g. empty lookahead patterns.
This means that it can't be used for a whole class of interesting
cases.  This has been discussed previously:

    http://bugs.python.org/issue3262
    http://bugs.python.org/issue852532
    http://bugs.python.org/issue988761

- It'd be nice to have a version of split that generates the parts
(one by one) rather than returning the whole list.

- Repeated subgroup match information is not available.  That is, for
a match like this

    re.match('(.){3}', 'xyz')

there's no way to discover that the subgroup first matched 'x', then
matched 'y', and finally matched 'z'.  Here is one past proposal
(mine), perhaps over-complex, to address this problem:

    http://mail.python.org/pipermail/python-dev/2004-August/047238.html

Mike



From Omer.Khalid at cern.ch  Wed Jul 29 11:26:55 2009
From: Omer.Khalid at cern.ch (Omer Khalid)
Date: Wed, 29 Jul 2009 17:26:55 +0200
Subject: Very Strange Problem
Message-ID: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>

Hi,

I am having a very strange problem with modifying a variable in a list in my
program. Here is the code:

# a list that contains dictionary objects
jobs = []

index=5
for each in range(index):
         jobs.append({'v':0})

some_function(index):
       if jobs[index]['v'] == 0:
                   # set it to 1
                   jobs[index]['v'] = 1
                   print "Set to 1"
      else:
                   print "Already set to 1"

loop():
        index=0
        for each in range(len(jobs)):
                 some_function(index)
                 index +=1


Apparently, the jobs[index]['v'] never get updated in the some_function but
the print statement afterwards get printed...

What's really surprising is that there are no errors or exceptions and my my
program runs in a single thread...so i have been unable to explain this
behavior.

Any insight would be much appreciated!

Cheers
Omer
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/56133f08/attachment.html>

From deets at nospam.web.de  Wed Jul 29 11:32:36 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 29 Jul 2009 17:32:36 +0200
Subject: Clearing an array
References: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>
Message-ID: <7db8ckF28m03sU1@mid.uni-berlin.de>

WilsonOfCanada wrote:

> Hellos,
> 
> I was wondering if there is any built-in function that clears the
> array.  I was also wondering if this works:
> 
> arrMoo = ['33', '342', .... '342']
> arrMoo = []

Most of the time, yes. Unless you have something like this, then it won't
work:


foo = [10]

bar = foo # an alias

foo = []

assert foo == bar

Then what you need to to is this:

foo[:] = []


Diez


From tack at urandom.ca  Wed Jul 29 11:39:00 2009
From: tack at urandom.ca (Jason Tackaberry)
Date: Wed, 29 Jul 2009 11:39:00 -0400
Subject: Clearing an array
In-Reply-To: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>
References: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>
Message-ID: <1248881940.7696.28.camel@willow>

On Wed, 2009-07-29 at 08:24 -0700, WilsonOfCanada wrote:
> I was wondering if there is any built-in function that clears the
> array.

The proper python term would be "list."  You can remove all elements of
a list 'l' like so:

   del l[:]


>   I was also wondering if this works:
> 
> arrMoo = ['33', '342', .... '342']
> arrMoo = []

That doesn't clear the list as such, but rather creates a new list, and
reassigns the new list to the 'arrMoo' name in the local scope.
Consider:

        >>> l1 = [1,2,3]
        >>> l2 = l1
        >>> l1 = []
        >>> print l2
        [1, 2, 3]

So the original list 'l1' lives on.  However:

        >>> l1 = [1,2,3]
        >>> l2 = l1
        >>> del l1[:]
        >>> print l1, l2
        [] []

Cheers,
Jason.



From tjreedy at udel.edu  Wed Jul 29 11:43:12 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 29 Jul 2009 11:43:12 -0400
Subject: python 3 and stringio.seek
In-Reply-To: <ECDBC5EB-B60D-4F54-81A8-9989C33AA70C@umich.edu>
References: <h4mui9$q1o$1@nnrp-beta.newsland.it>
	<ECDBC5EB-B60D-4F54-81A8-9989C33AA70C@umich.edu>
Message-ID: <h4pqmf$pjc$1@ger.gmane.org>

Miles Kaufmann wrote:
> 
> On Jul 28, 2009, at 6:30 AM, Michele Petrazzo wrote:
> 
>> Hi list,
>> I'm trying to port a my library to python 3, but I have a problem with a
>> the stringio.seek:
>> the method not accept anymore a value like pos=-6 mode=1, but the "old"
>> (2.X) version yes...
>>
>> The error:
>>  File "/home/devel/Py3/lib/python3.0/io.py", line 2031, in seek
>>    return self._seek(pos, whence)
>> IOError: Can't do nonzero cur-relative seeks
>>
>>
>> How solve this?
> 
> In Python 2, StringIO is a stream of bytes (non-Unicode characters).  In 
> Python 3, StringIO is a stream of text (Unicode characters).  In the 
> early development of Python 3 (and 3.1's _pyio), it was implemented as a 
> TextIOWrapper over a BytesIO buffer.  TextIOWrapper does not support 
> relative seeks because it is difficult to map the concept of a "current 
> position" between bytes and the text that it encodes, especially with 
> variable-width encodings and other considerations.  Furthermore, the 
> value returned from TextIOWrapper.tell isn't just a file position but a 
> "cookie" that contains other data necessary to restore the decoding 
> mechanism to the same state.  However, for the default encoding (utf-8), 
> the current position is equivalent to that of the underlying bytes buffer.
> 
> In Python 3, StringIO is implemented using an internal buffer of Unicode 
> characters.  There is no technical reason why it can't support relative 
> seeks; I assume it does not for compatibility with the original Python 
> TextIOWrapper implementation (which is present in 3.1's _pyio, but not 
> in 3.0).
> 
> Note that because of the different implementations, StringIO.tell() (and 
> seek) behaves differently for the C and Python implementations:
> 
> $ python3.1
>  >>> import io, _pyio
>  >>> s = io.StringIO('\u263A'); s.read(1), s.tell()
> ('?', 1)
>  >>> s = _pyio.StringIO('\u263A'); s.read(1), s.tell()
> ('?', 3)

It seems to me that this discrepancy might be worth a tracker item.
I wonder why the second implementation is even there if not used.
Two different commiters?

> The end result seems to be that, for text streams (including StreamIO), 
> you *should* treat the value returned by tell() as an opaque magic 
> cookie, and *only* pass values to seek() that you have obtained from a 
> previous tell() call.  However, in practice, it appears that you *may* 
> seek StringIO objects relatively by characters using s.seek(s.tell() + 
> n), so long as you do not use the _pyio.StringIO implementation.

A tracker item could include a request that relative seek be restored if 
possible.

tjr



From python at mrabarnett.plus.com  Wed Jul 29 11:45:55 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 16:45:55 +0100
Subject: New implementation of re module
In-Reply-To: <215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com>
Message-ID: <4A706EB3.1040501@mrabarnett.plus.com>

Mike wrote:
> On Jul 27, 11:34 am, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> I've been working on a new implementation of the re module.
> 
> Fabulous!
> 
> If you're extending/changing the interface, there are a couple of sore
> points in the current implementation I'd love to see addressed:
> 
> - findall/finditer doesn't find overlapping matches.  Sometimes you
> really *do* want to know all possible matches, even if they overlap.
> This comes up in bioinformatics, for example.
> 
Perhaps by adding "overlapped=True"?

> - split won't split on empty patterns, e.g. empty lookahead patterns.
> This means that it can't be used for a whole class of interesting
> cases.  This has been discussed previously:
> 
>     http://bugs.python.org/issue3262
>     http://bugs.python.org/issue852532
>     http://bugs.python.org/issue988761
> 
Already addressed (see issue2636 for the full details).

> - It'd be nice to have a version of split that generates the parts
> (one by one) rather than returning the whole list.
> 
Hmm, re.splititer() perhaps.

> - Repeated subgroup match information is not available.  That is, for
> a match like this
> 
>     re.match('(.){3}', 'xyz')
> 
> there's no way to discover that the subgroup first matched 'x', then
> matched 'y', and finally matched 'z'.  Here is one past proposal
> (mine), perhaps over-complex, to address this problem:
> 
>     http://mail.python.org/pipermail/python-dev/2004-August/047238.html
> 
Yikes! I think I'll let you code that... :-)


From mdboldin at gmail.com  Wed Jul 29 11:49:49 2009
From: mdboldin at gmail.com (mpython)
Date: Wed, 29 Jul 2009 08:49:49 -0700 (PDT)
Subject: SEC forms parsing
Message-ID: <ffa37df5-3eb9-40d6-929d-397fa80b4fbc@h30g2000vbr.googlegroups.com>

I am looking for any python examples that have written to parse SEC
filings (Security Exchange Commission's EDGAR system),or just a
pointer to best modules to use.


From python at mrabarnett.plus.com  Wed Jul 29 11:53:47 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 16:53:47 +0100
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
Message-ID: <4A70708B.4030402@mrabarnett.plus.com>

Omer Khalid wrote:
> Hi,
> 
> I am having a very strange problem with modifying a variable in a list 
> in my program. Here is the code:
> 
> # a list that contains dictionary objects
> jobs = []
> 
> index=5
> for each in range(index):
>          jobs.append({'v':0})
> 
> some_function(index):
>        if jobs[index]['v'] == 0:
>                    # set it to 1
>                    jobs[index]['v'] = 1
>                    print "Set to 1"
>       else:
>                    print "Already set to 1"
> 
> loop():
>         index=0
>         for each in range(len(jobs)):
>                  some_function(index)
>                  index +=1
> 
> 
> Apparently, the jobs[index]['v'] never get updated in the some_function 
> but the print statement afterwards get printed...
> 
> What's really surprising is that there are no errors or exceptions and 
> my my program runs in a single thread...so i have been unable to explain 
> this behavior.
> 
> Any insight would be much appreciated!
> 
Well, when I insert the missing 'def's in the function definitions, it
works for me.


From ronn.ross at gmail.com  Wed Jul 29 11:57:18 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Wed, 29 Jul 2009 10:57:18 -0500
Subject: Can you easy_install from your localhost?
Message-ID: <9c8c445f0907290857x27930acbvc5067a242e18ed17@mail.gmail.com>

I have a package i would like to store locally. If it is stored locally can
I do something like ' easy_install http://localhost/package ' ? Thanks
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/ecf1262c/attachment.html>

From invalid at invalid  Wed Jul 29 12:02:53 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 29 Jul 2009 11:02:53 -0500
Subject: Compiling Python for uCLinux appliance?
References: <7sk075l5p7eq8mek9ooqj5kr0ds10hrvfq@4ax.com>
	<7db5mnF2bf9i2U1@mid.uni-berlin.de>
Message-ID: <N-SdnVnsn7Yw7-3XnZ2dnUVZ_hGdnZ2d@posted.visi>

On 2009-07-29, Diez B. Roggisch <deets at nospam.web.de> wrote:
> Gilles Ganault wrote:
>
>> Hello
>> 
>> I just got a small appliance based on a Blackfin CPU with 64MB RAM and
>> 258MB NAND flash. Using the stock software, there's about 30MB of RAM
>> left.
>> 
>> Besides C/C++ and shel scripts, I was wondering if it were realistic
>> to upload a few Python scripts in such a small appliance?

The standard uclinux-dist comes with python, so it's pretty
much just a question of memory.  Asking on the uclinux mailing
list will probably be more useful, but I would guess that 64MB
would be plenty -- especially if use JFFS to put your root
filesystem in flash instead of in RAM.  Of course it depends
entirely on what else you want to do with that RAM at the same
time...

> Try & check out the gumstix software repo. It comes with
> python, and thus some crosscompiling/build-instructions should
> be in there.

IIRC, all you have to do is "make menuconfig", go to the user
apps page and check the "Python" box, and then "make".  It
should "just work".

-- 
Grant Edwards                   grante             Yow! I haven't been married
                                  at               in over six years, but we
                               visi.com            had sexual counseling every
                                                   day from Oral Roberts!!


From ryniek90 at gmail.com  Wed Jul 29 12:11:32 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 29 Jul 2009 18:11:32 +0200
Subject: how to embed the python interpreter into web App (Mehndi, Sibtey)
In-Reply-To: <mailman.14496.1248881699.8014.python-list@python.org>
References: <mailman.14496.1248881699.8014.python-list@python.org>
Message-ID: <4A7074B4.2070204@gmail.com>

>
>
> Hi All
>
> I am trying to embed the python interpreter in to a web app but could 
> not get the way, any one can suggest me how to do this.
>
>  
>
> Thanks,
>
> Sibtey Mehdi
>
>  
>
> This e-mail (and any attachments), is confidential and may be privileged. It may be read, copied and used only
> by intended recipients. Unauthorized access to this e-mail (or attachments) and disclosure or copying of its 
> contents or any action taken in reliance on it is unlawful. Unintended recipients must notify the sender immediately 
> by e-mail/phone & delete it from their system without making any copies or disclosing it to a third person.
>
>
>   

Here's example: http://try-python.mired.org/

Contact with author of that website/webapp.

Good luck.


From python at mrabarnett.plus.com  Wed Jul 29 12:53:33 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 17:53:33 +0100
Subject: Very Strange Problem
In-Reply-To: <4A7074E6.9030100@gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
	<4A70708B.4030402@mrabarnett.plus.com> <4A7074E6.9030100@gmail.com>
Message-ID: <4A707E8D.4020306@mrabarnett.plus.com>

Ricardo Ar?oz wrote:
> MRAB wrote:
>> Omer Khalid wrote:
>>> Hi,
>>>
>>> I am having a very strange problem with modifying a variable in a 
>>> list in my program. Here is the code:
>>>
>>> # a list that contains dictionary objects
>>> jobs = []
>>>
>>> index=5
>>> for each in range(index):
>>>          jobs.append({'v':0})
>>>
>>> some_function(index):
>>>        if jobs[index]['v'] == 0:
>>>                    # set it to 1
>>>                    jobs[index]['v'] = 1
>>>                    print "Set to 1"
>>>       else:
>>>                    print "Already set to 1"
>>>
>>> loop():
>>>         index=0
>>>         for each in range(len(jobs)):
>>>                  some_function(index)
>>>                  index +=1
>>>
>>>
>>> Apparently, the jobs[index]['v'] never get updated in the 
>>> some_function but the print statement afterwards get printed...
>>>
>>> What's really surprising is that there are no errors or exceptions 
>>> and my my program runs in a single thread...so i have been unable to 
>>> explain this behavior.
>>>
>>> Any insight would be much appreciated!
>>>
>> Well, when I insert the missing 'def's in the function definitions, it
>> works for me.
> Hi Omer, what he is trying to convey in his rude manner is that you are 
> missing "def" in your function definitions. It is probably a beginners 
> mistake.
> 
> That is :
> from "some_function(index): "
> to "def some_function(index): "
> 
> from "loop(): "
> to "def loop(): "
> 
> I have not tried your code so you should believe him when he states he 
> has actually run the code.
> HTH
> 
Omer says "the print statement afterwards get printed", but the code
provided would have raised a SyntaxError, so omitting the 'def's can't
be the cause of the actual problem reported.


From nagle at animats.com  Wed Jul 29 13:10:15 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 29 Jul 2009 10:10:15 -0700
Subject: bad certificate error
In-Reply-To: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
Message-ID: <4a7081c9$0$1600$742ec2ed@news.sonic.net>

jakecjacobson wrote:
> Hi,
> 
> I am getting the following error when doing a post to REST API,
> 
> Enter PEM pass phrase:
> Traceback (most recent call last):
>   File "./ices_catalog_feeder.py", line 193, in ?
>     main(sys.argv[1])
>   File "./ices_catalog_feeder.py", line 60, in main
>     post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
> (input_dir, file), collection_name, key_file, cert_file)
>   File "./ices_catalog_feeder.py", line 125, in post2Catalog
>     connection.request('POST', path, parameters, head)
>   File "/usr/lib/python2.4/httplib.py", line 810, in request
>     self._send_request(method, url, body, headers)
>   File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
>     self.endheaders()
>   File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
>     self._send_output()
>   File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
>     self.send(msg)
>   File "/usr/lib/python2.4/httplib.py", line 652, in send
>     self.connect()
>   File "/usr/lib/python2.4/httplib.py", line 1079, in connect
>     ssl = socket.ssl(sock, self.key_file, self.cert_file)
>   File "/usr/lib/python2.4/socket.py", line 74, in ssl
>     return _realssl(sock, keyfile, certfile)
> socket.sslerror: (1, 'error:14094412:SSL
> routines:SSL3_READ_BYTES:sslv3 alert bad certificate')

    What SSL implementation are you using?  The old one from Python 2.4
doesn't even check the certificate chain.  M2Crypto does, and the new
SSL module does, but in each case you have to provide a root certificate
file.  (The one from Mozilla is available.)

					John Nagle


From nagle at animats.com  Wed Jul 29 13:12:27 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 29 Jul 2009 10:12:27 -0700
Subject: SEC forms parsing
In-Reply-To: <ffa37df5-3eb9-40d6-929d-397fa80b4fbc@h30g2000vbr.googlegroups.com>
References: <ffa37df5-3eb9-40d6-929d-397fa80b4fbc@h30g2000vbr.googlegroups.com>
Message-ID: <4a70824d$0$1600$742ec2ed@news.sonic.net>

mpython wrote:
> I am looking for any python examples that have written to parse SEC
> filings (Security Exchange Commission's EDGAR system),or just a
> pointer to best modules to use.

    I've been doing that in Perl for years.  See "www.downside.com".

    Actually extracting financial statements is possible, but you
run into a patent problem with a Price-Waterhouse patent if you try
to do a good job.

    What are you trying to do?

				John Nagle


From piet at cs.uu.nl  Wed Jul 29 13:17:51 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 29 Jul 2009 19:17:51 +0200
Subject: Help with sql and python
References: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>
Message-ID: <m2bpn3e7cw.fsf@cs.uu.nl>

>>>>> "catalinfest at gmail.com" <catalinfest at gmail.com> (cc) wrote:

>cc> Hello !
>cc> I have accont on myphpadmin on my server.
>cc> I want to create one script in python.
>cc> This script manage sql task from my sql server .
>cc> How i make this in a simple way ?

See http://mysql-python.sourceforge.net/MySQLdb.html

This really has nothing to do with myphpadmin (you probably mean
phpMyAdmin but even then it has nothing to do with it except that both
acess a MySQL database).

And if you give yourself a name than we might have an idea if we are
talking to a human being or a robot.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From tutufan at gmail.com  Wed Jul 29 13:21:39 2009
From: tutufan at gmail.com (Mike)
Date: Wed, 29 Jul 2009 10:21:39 -0700 (PDT)
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org> 
	<215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com> 
	<mailman.3899.1248882356.8015.python-list@python.org>
Message-ID: <19a1cbfa-6594-4956-bc3c-f1fd3108091a@c29g2000yqd.googlegroups.com>

On Jul 29, 10:45?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Mike wrote:
> > - findall/finditer doesn't find overlapping matches. ?Sometimes you
> > really *do* want to know all possible matches, even if they overlap.
>
> Perhaps by adding "overlapped=True"?

Something like that would be great, yes.


> > - split won't split on empty patterns, e.g. empty lookahead patterns.

> Already addressed (see issue2636 for the full details).

Glad to hear it.


> > - Repeated subgroup match information is not available. ?That is, for
> > a match like this
>
> > ? ? re.match('(.){3}', 'xyz')
>
> > there's no way to discover that the subgroup first matched 'x', then
> > matched 'y', and finally matched 'z'. ?Here is one past proposal
> > (mine), perhaps over-complex, to address this problem:
>
> > ? ?http://mail.python.org/pipermail/python-dev/2004-August/047238.html
>
> Yikes! I think I'll let you code that... :-)

I agree that that document looks a little scary--maybe I was trying to
bite off too much at once.

My intuition, though, is that the basic idea should be fairly simple
to implement, at least for a depth-first matcher.  The repeated match
subgroups are already being discovered, it's just that they're not
being saved, so there's no way to report them out once a complete
match is found.  If some trail of breadcrumbs were pushed onto a stack
during the DFS, it could be traced at the end.  And the whole thing
might not even been that expensive to do.

The hardest parts about this, in my mind, are figuring out how to
report the repeated matches out in a useful form (hence all that
detail in the proposal), and getting users to understand that using
this feature *could* suck up a lot of memory, if they're not careful.

As always, it's possible that my intuition is totally wrong.  Plus I'm
not sure how this would work out in the breadth-first case.

Details aside, I would really, really, really like to have a way to
get at the repeated subgroup matches.  I write a lot of code that
would be one-liners if this capability existed.  Plus, it just plain
burns me that Python is discovering this information but impudently
refuses to tell me what it's found!  ;-)




From piet at cs.uu.nl  Wed Jul 29 13:26:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 29 Jul 2009 19:26:26 +0200
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
	<cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>
	<7d5brmF2a1alcU1@mid.uni-berlin.de>
	<2b5b00b8-f9ba-4d16-b950-681aa6fa010a@24g2000yqm.googlegroups.com>
Message-ID: <m27hxre6yl.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>>> The Exact Problem is how to use the key containing by .pem file for
>>> 'encryption' . can i print the contents of the .pem file

I have already answered this question in a previous thread. It is not
very helpful if you repeat asking the same or similar questions in
different threads, especially if you don't take notice of the answers
given. I will repeat it once here:

load_pub_key requires a file name, not the contents of the file.
So use rsa = M2Crypto.RSA.load_pub_key('my_key.public.pem') and leave
the open line out.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From dandi.kain at gmail.com  Wed Jul 29 13:59:55 2009
From: dandi.kain at gmail.com (dandi kain)
Date: Wed, 29 Jul 2009 10:59:55 -0700 (PDT)
Subject: Does underscore has any special built-in meaningin Python ?
Message-ID: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>

Hello everybody,
I have just started learning Python.I heard its simple so I pick a
presentation [1] and tried to work on it.But when it comes to
underscores leading and trailing an object I dont understand any.I
look through the python manual also but that was not helping .I
searched some forums and I still dont have a clear picture.

What is the functionality of __ or _ , leading or trailing an object ,
class ot function ? Is it just a naming convention to note special
functions and objects , or it really mean someting to Python ?

Thanks ahead ,

[1] http://www.aleax.it/goo_py4prog.pdf


From lemmath at gmail.com  Wed Jul 29 14:04:49 2009
From: lemmath at gmail.com (Vincent Vega)
Date: Wed, 29 Jul 2009 11:04:49 -0700 (PDT)
Subject: Print value CLOB via cx_Oracle
References: <6de8842b-f1c6-460e-a705-4f6dbd81492c@a26g2000yqn.googlegroups.com>
Message-ID: <372c160b-eee2-46f3-913c-f75d84f45e11@c14g2000yqm.googlegroups.com>

On 28 Lip, 20:02, Vincent Vega <lemm... at gmail.com> wrote:
> Hi,
>
> I call function in Oracle database use cx_Oracle.
> In standard I define:
>
> db ? ? ? = cx_Oracle.connect(username, password, tnsentry)
> cursor ?= db.cursor()
>
> I create variable 'y' (result function 'fun_name') and call function
> 'fun_name':
>
> y ? = cursor.var(cx_Oracle.CLOB)
> cursor.callfunc(fun_name, cx_Oracle.CLOB, y)
>
> When I print variable 'y' I receive:
> <cx_Oracle.CLOB with value <cx_Oracle.LOB object at 0x00999999>>
>
> How can I get value variable 'y'???
> How read <cx_Oracle.LOB object at 0x00999999>???
>
> Vincent Vega
>
> Note:
> Off course y.read() does not work, cause 'y'is CLOB not LOB.
> (see datatypes table in site:http://www.oracle.com/technology/pub/articles/prez-python-queries.html)

The solution is simple:

print y.getvalue()

(see: http://cx-oracle.sourceforge.net/html/variable.html)

Thanks! :)

Vincent Vega


From davea at ieee.org  Wed Jul 29 14:05:28 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:05:28 -0400
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
Message-ID: <4A708F68.1010505@ieee.org>

Barak, Ron wrote:
> Hi,
>
> I wanted to make a python byte-code file executable, expecting to be able to run it without specifying "python" on the (Linux bash) command line.
>
> So, I wrote the following:
>
> [root at VMLinux1 python]# cat test_pyc.py
> #!/usr/bin/env python
>
> print "hello"
> [root at VMLinux1 python]#
>
> and made its pyc file executable:
>
> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> [root at VMLinux1 python]#
>
> So, I see:
>
> [root at VMLinux1 python]# file test_pyc.py*
> test_pyc.py:  a python script text executable
> test_pyc.pyc: python 2.3 byte-compiled
> [root at VMLinux1 python]#
>
> If I try to do the following, no problem:
>
> [root at VMLinux1 python]# python test_pyc.pyc
> hello
> [root at VMLinux1 python]#
>
> However, the following fails:
>
> [root at VMLinux1 python]# ./test_pyc.pyc
> -bash: ./test_pyc.pyc: cannot execute binary file
> [root at VMLinux1 python]#
>
> Is there a way to run a pyc file without specifying the python path ?
>
> Bye,
> Ron.
>
>   
I don't currently run Unix, but I think I know the problem.

In a text file, the shell examines the first line, and if it begins #! 
it's assumed to point to the executable of an interpreter for that text 
file.  Presumably the same trick doesn't work for a .pyc file.

Why not write a trivial wrapper.py file, don't compile it, and let that 
invoke the main code in the .pyc file?

Then make wrapper.py executable, and you're ready to go.

DaveA



From benjamin.kaplan at case.edu  Wed Jul 29 14:08:07 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Wed, 29 Jul 2009 14:08:07 -0400
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>

On Wed, Jul 29, 2009 at 1:59 PM, dandi kain <dandi.kain at gmail.com> wrote:
>
> Hello everybody,
> I have just started learning Python.I heard its simple so I pick a
> presentation [1] and tried to work on it.But when it comes to
> underscores leading and trailing an object I dont understand any.I
> look through the python manual also but that was not helping .I
> searched some forums and I still dont have a clear picture.
>
> What is the functionality of __ or _ , leading or trailing an object ,
> class ot function ? Is it just a naming convention to note special
> functions and objects , or it really mean someting to Python ?

It's just a convention for the most part. A single leading underscore
is used for "private" attributes. Two leading underscores will affect
the code- it mangles the variable name so that you don't have to worry
about the value being overwritten by a subclass. For instance
"""
class Foo(object) :
   def __init__(self) :
       self.__bar = ''

foo = Foo()
""
will store the attribute as foo._Foo__bar.

Also, the "magic methods"- the ones that are used for operations and
built-in stuff, all have two leading and two trailing underscores.
These are things like __add__ (+), __eq__ (=), __cmp__ (old way for
comparisons), __len__ (len), __str__ (str), and so on.


>
> Thanks ahead ,
>
> [1] http://www.aleax.it/goo_py4prog.pdf
> --
> http://mail.python.org/mailman/listinfo/python-list


From martin.hellwig at dcuktec.org  Wed Jul 29 14:16:31 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Wed, 29 Jul 2009 19:16:31 +0100
Subject: simple splash screen?
In-Reply-To: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
Message-ID: <LYudnbbBM-OdD-3XnZ2dnUVZ8opi4p2d@bt.com>

NighterNet wrote:
> I am trying to make a simple splash screen from python 3.1.Not sure
> where to start looking for it. Can any one help?

Sure, almost the same as with Python 2 :-)
But to be a bit more specific:
++++
"""Only works if you got Python 3 installed with tkinter"""
import tkinter

IMAGE_PATH = "/path/to/image"

class Splash(object):
     "Splash Screen GUI"
     def __init__(self, root):
         self.root = root
         # No window borders and decoration
         self.root.overrideredirect(True)
         # Get the size of the screen
         screen_width = self.root.winfo_screenwidth()
         screen_height = self.root.winfo_screenheight()
         # Full screen
         geometry_text = "%dx%d+0+0" % (screen_width, screen_height)
         self.root.geometry(geometry_text)
         # Display an image
         self.label = tkinter.Label(self.root)
         # Only GIF and PGM/PPM supported, for more information see:
         self.label._image = tkinter.PhotoImage(file=IMAGE_PATH)
         # http://effbot.org/tkinterbook/photoimage.htm
         self.label.configure(image = self.label._image)
         self.label.pack()
         # This will quit the screen after about 5 seconds
         self.root.after(5000, self.root.quit)

if __name__ == '__main__':
     ROOT = tkinter.Tk()
     APPL = Splash(ROOT)
     ROOT.mainloop()
++++

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From davea at ieee.org  Wed Jul 29 14:19:32 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:19:32 -0400
Subject: Help with sql and python
In-Reply-To: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>
References: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>
Message-ID: <4A7092B4.8090609@ieee.org>

catalinfest at gmail.com wrote:
> Hello !
>
> I have accont on myphpadmin on my server.
> I want to create one script in python.
> This script manage sql task from my sql server .
> How i make this in a simple way ?
>
> Thank you !
>
>   
It's seldom simple.

I'm guessing it's not your server, but is actually a webserver, located 
remotely, and to which you have only ftp access.

Next questions are do you have access to the admins of the machine, what 
kind of machine is it, what OS is it running, does it have Python 
installed, what version(s)?

Next questions are dependent on the answers to those questions.  For 
example, on Unix systems you'll generally need to be able to chmod the file.

But before you ask your admins those questions, you need to ask how you 
*want* to run the script.  Creating it isn't enough, if you don't run 
it.  You might be running it over the web, via URL, perhaps using CGI.  
You might be activating it via some remote console, or rsh.  Or it might 
be a cron job.  It might need various privileges to do what you expect.  
And if it's going to run continuously, or if it uses lots of resources, 
the admins may refuse it entirely.

DaveA



From electriclightheads at gmail.com  Wed Jul 29 14:26:47 2009
From: electriclightheads at gmail.com ('2+)
Date: Thu, 30 Jul 2009 03:26:47 +0900
Subject: instead of depending on data = array('h') .. write samples 1 by 1
	to w = wave.open("wav.wav", "w")
In-Reply-To: <h4p0p8$l9k$01$1@news.t-online.com>
References: <mailman.3855.1248811181.8015.python-list@python.org>
	<h4p0p8$l9k$01$1@news.t-online.com>
Message-ID: <1078018b0907291126t32c453a7h1f2a86fc270d3701@mail.gmail.com>

o wow .. there's still a lot to learn ..
okay .. if i get stucked with the memory usage issue
will try this hybrid .. thanx for the example!!

it took about 40 min to render 1min of wav
so i'll just keep this project like 15 sec oriented
and maybe that'll keep me away from the mem trouble

and my oil.py is still so cheap..
sad thing is that "the result sound strange" is true to
all versions :s

thanx again anyway!


On Wed, Jul 29, 2009 at 5:21 PM, Peter Otten<__peter__ at web.de> wrote:
> '2+ wrote:
>
>> it says
>> Wave_write.writeframes(data)
>> will that mean
>> "from array import array"
>> is a must?
>>
>> this does the job:
>>
>> import oil
>> import wave
>> from array import array
>>
>> a = oil.Sa()
>>
>> w = wave.open("current.wav", "w")
>> w.setnchannels(2)
>> w.setsampwidth(2)
>> w.setframerate(44100)
>>
>> data = array('h')
>>
>> for gas in range(44100 * 5):
>> ? ? a.breath()
>> ? ? r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>> ? ? l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>> ? ? data.append(r)
>> ? ? data.append(l)
>>
>> w.writeframes(data.tostring())
>> w.close()
>>
>> don't like array becoming so huge so tested this and it was also okay:
>>
>> for gas in range(44100 * 5):
>> ? ? a.breath()
>> ? ? data = array('h')
>> ? ? r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>> ? ? l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>> ? ? data.append(r)
>> ? ? data.append(l)
>> ? ? w.writeframes(data.tostring())
>>
>> but without array .. it becomes 15secs(3 times longer than was
>> intended to be) of wav file:
>>
>> for gas in range(44100 * 5):
>> ? ? a.breath()
>> ? ? r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>> ? ? l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>> ? ? w.writeframes(hex(r))
>> ? ? w.writeframes(hex(l))
>
> Doesn't it sound strange, too? You are writing bogus bytes to the file.
> Compare:
>
>>>> import array
>>>> array.array("h", [42]).tostring()
> '*\x00'
>>>> hex(42)
> '0x2a'
>
> Not only do they differ in length, the contents are different, too. If
> you're unfamiliar with string escape codes, here's a way to see the bytes:
>
>>>> map(ord, array.array("h", [42]).tostring())
> [42, 0]
>>>> map(ord, hex(42))
> [48, 120, 50, 97]
>
>> should i just be happy with depennding on using array?
>> or is there a solution to make the last one work properly?
>
> There is a way to make the last one work: use struct.pack("h", r) instead of
> hex(r). I'm of course assuming that the first version does give you the
> desired result. You should not continue before you have verified that.
>
> I still recommend array for performance reasons. If memory usage is an issue
> you can adopt a hybrid approach:
>
> # untested
> from itertools import islice
> from array import array
>
> def gen_data():
> ? ?for gas in xrange(44100 * 5): # range --> xrange
> ? ? ? ?a.breath()
> ? ? ? ?r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
> ? ? ? ?l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
> ? ? ? ?yield r
> ? ? ? ?yield l
>
> data = gen_data()
> N = 2**20
> while True:
> ? ?chunk = array('h')
> ? ?chunk.extend(islice(data, N))
> ? ?if not chunk:
> ? ? ? ?break
> ? ?w.writeframes(chunk.tostring())
>
> This will limit the array size to 4N bytes.
>
> Peter
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
SaRiGaMa's Oil Vending Orchestra
is podcasting:
http://sarigama.namaste.jp/podcast/rss.xml
and supplying oil.py for free:
http://oilpy.blogspot.com/


From davea at ieee.org  Wed Jul 29 14:33:25 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:33:25 -0400
Subject: escaping characters in filenames
In-Reply-To: <854osv7h2k.fsf@agentultra.com>
References: <854osv7h2k.fsf@agentultra.com>
Message-ID: <4A7095F5.6090100@ieee.org>

J Kenneth King wrote:
> I wrote a script to process some files using another program.  One thing
> I noticed was that both os.listdir() and os.path.walk() will return
> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
> module or recipe that escapes file names and was wondering if anyone
> could point me in the right direction.
>
> As an aside, the script is using subprocess.call() with the "shell=True"
> parameter.  There isn't really a reason for doing it this way (was just
> the fastest way to write it and get a prototype working).  I was
> wondering if Popen objects were sensitive to unescaped names like the
> shell.  I intend to refactor the function to use Popen objects at some
> point and thought perhaps escaping file names may not be entirely
> necessary.
>
> Cheers
>
>   
There are dozens of meanings for escaping characters in strings.  
Without some context, we're wasting our time.

For example, if the filename is to be interpreted as part of a URL, then 
spaces are escaped by using %20.   Exactly who is going to be using this 
string you think you have to modify?  I don't know of any environment 
which expects spaces to be escaped with backslashes.

Be very specific.  For example, if a Windows application is parsing its 
own command line, you need to know what that particular application is 
expecting -- Windows passes the entire command line as a single string.  
But of course you may be invoking that application using 
subprocess.Popen(), in which case some transformations happen to your 
arguments before the single string is built.  Then some more 
transformations may happen in the shell.  Then some more in the C 
runtime library of the new process (if it happens to be in C, and if it 
happens to use those libraries).

I'm probably not the one with the answer.  But until you narrow down 
your case, you probably won't attract the attention of whichever person 
has the particular combination of experience that you're hoping for.

DaveA



From jdgiotta at gmail.com  Wed Jul 29 14:39:55 2009
From: jdgiotta at gmail.com (John D Giotta)
Date: Wed, 29 Jul 2009 11:39:55 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
Message-ID: <cbfcfb6e-ca37-4631-b25c-e0162a53d426@32g2000yqj.googlegroups.com>

I'm working with up to 3 process "session" per server, each process
running three threads.
I was wishing to tie back the 3 "session"/server to a semaphore, but
everything (and everyone) say semaphores are only good per process.


From jdgiotta at gmail.com  Wed Jul 29 14:43:07 2009
From: jdgiotta at gmail.com (John D Giotta)
Date: Wed, 29 Jul 2009 11:43:07 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<m2bpn44c8i.fsf@valheru.db3l.homeip.net>
Message-ID: <171f69c0-44ae-4624-bd03-a47032e82c21@n11g2000yqb.googlegroups.com>

That was my original idea. Restricting each process by pid:

#bash
procs=`ps aux | grep script.pl | grep -v grep | wc -l`

if [ $procs -lt 3 ]; then
        python2.4 script.py config.xml
else
        exit 0
fi


From lists at cheimes.de  Wed Jul 29 14:53:49 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 29 Jul 2009 20:53:49 +0200
Subject: Semaphore Techniques
In-Reply-To: <cbfcfb6e-ca37-4631-b25c-e0162a53d426@32g2000yqj.googlegroups.com>
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
	<cbfcfb6e-ca37-4631-b25c-e0162a53d426@32g2000yqj.googlegroups.com>
Message-ID: <h4q5rt$us8$1@ger.gmane.org>

John D Giotta schrieb:
> I'm working with up to 3 process "session" per server, each process
> running three threads.
> I was wishing to tie back the 3 "session"/server to a semaphore, but
> everything (and everyone) say semaphores are only good per process.

That's not true. Named semaphores are the best solution for your problem
and I said so yesterday.

Christian



From nobody at nowhere.com  Wed Jul 29 14:55:16 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 19:55:16 +0100
Subject: escaping characters in filenames
References: <854osv7h2k.fsf@agentultra.com>
Message-ID: <pan.2009.07.29.18.55.16.468000@nowhere.com>

On Wed, 29 Jul 2009 09:29:55 -0400, J Kenneth King wrote:

> I wrote a script to process some files using another program.  One thing
> I noticed was that both os.listdir() and os.path.walk() will return
> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
> module or recipe that escapes file names and was wondering if anyone
> could point me in the right direction.
> 
> As an aside, the script is using subprocess.call() with the "shell=True"
> parameter.  There isn't really a reason for doing it this way (was just
> the fastest way to write it and get a prototype working).  I was
> wondering if Popen objects were sensitive to unescaped names like the
> shell.  I intend to refactor the function to use Popen objects at some
> point and thought perhaps escaping file names may not be entirely
> necessary.

Note that subprocess.call() is nothing more than:

	def call(*popenargs, **kwargs):
	    return Popen(*popenargs, **kwargs).wait()

plus a docstring. It accepts exactly the same arguments as Popen(), with
the same semantics.

If you want to run a command given a program and arguments, you
should pass the command and arguments as a list, rather than trying to
construct a string.

On Windows the value of shell= is unrelated to whether the command is
a list or a string; a list is always converted to string using the
list2cmdline() function. Using shell=True simply prepends "cmd.exe /c " to
the string (this allows you to omit the .exe/.bat/etc extension for
extensions which are in %PATHEXT%).

On Unix, a string is first converted to a single-element list, so if you
use a string with shell=False, it will be treated as the name of an
executable to be run without arguments, even if contains spaces, shell
metacharacters etc.

The most portable approach seems to be to always pass the command as a
list, and to set shell=True on Windows and shell=False on Unix.

The only reason to pass a command as a string is if you're getting a
string from the user and you want it to be interpreted using the
platform's standard shell (i.e. cmd.exe or /bin/sh). If you want it to be
interpreted the same way regardless of platform, parse it into a
list using shlex.split().



From mdekauwe at gmail.com  Wed Jul 29 14:56:28 2009
From: mdekauwe at gmail.com (Martin)
Date: Wed, 29 Jul 2009 11:56:28 -0700 (PDT)
Subject: set variable to looping index?
Message-ID: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>

Hi,

I am trying to set the return value from a function to a name which I
grab from the for loop. I can't work out how I can do this without
using an if statement...

for f in var1_fn, var2_fn, var3_fn:
    if f.split('.')[0] == 'var1':
        var1 = call_some_function(f)
	.
        .
        .
      etc

 Really I would like to remove the need for this if loop and I am sure
there is a simple way I am missing?

Many thanks

Martin



From davea at ieee.org  Wed Jul 29 14:56:55 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:56:55 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
Message-ID: <4A709B77.9080209@ieee.org>

Omer Khalid wrote:
> Hi,
>
> I am having a very strange problem with modifying a variable in a list in my
> program. Here is the code:
>
> # a list that contains dictionary objects
> jobs = []
>
> index=5
> for each in range(index):
>          jobs.append({'v':0})
>
> some_function(index):
>        if jobs[index]['v'] == 0:
>                    # set it to 1
>                    jobs[index]['v'] = 1
>                    print "Set to 1"
>       else:
>                    print "Already set to 1"
>
> loop():
>         index=0
>         for each in range(len(jobs)):
>                  some_function(index)
>                  index +=1
>
>
> Apparently, the jobs[index]['v'] never get updated in the some_function but
> the print statement afterwards get printed...
>
> What's really surprising is that there are no errors or exceptions and my my
> program runs in a single thread...so i have been unable to explain this
> behavior.
>
> Any insight would be much appreciated!
>
> Cheers
> Omer
>
>   
There are four things to fix before the program does anything much at 
all.  Two places you're missing the def, indentation is inconsistent, 
and you never actually call either of the functions.   The first three 
are syntax errors, so presumably your cut/paste in your computer is broken.

Once I make those four corrections, I get the following output:

Set to 1
Set to 1
Set to 1
Set to 1
Set to 1

But you never said what you got, nor what you expected.  That's 
certainly what I'd expect.  And if you make a second call to loop() in 
your outer code, you get five copies of "Already set to 1"

BTW, there are a number of things that could be done better.  The main 
one I'll point out is that you shouldn't re-use a global variable 
'index' as a local with different meaning.  As someone else pointed out, 
since the global is a constant, making it all uppercase is the convention.

DaveA



From martin at v.loewis.de  Wed Jul 29 15:06:31 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Wed, 29 Jul 2009 21:06:31 +0200
Subject: 64-bit issues with dictionaries in Python 2.6
In-Reply-To: <hpe5k6-ed5.ln1@nb2.stroeder.com>
References: <hpe5k6-ed5.ln1@nb2.stroeder.com>
Message-ID: <4a709db7$0$15886$9b622d9e@news.freenet.de>

> Are there any known issues with dictionaries in Python 2.6 (not 2.6.2)
> when running on a 64-bit platform?

No, none.

Regards,
Martin


From Omer.Khalid at cern.ch  Wed Jul 29 15:10:44 2009
From: Omer.Khalid at cern.ch (Omer Khalid)
Date: Wed, 29 Jul 2009 21:10:44 +0200
Subject: Very Strange Problem
In-Reply-To: <4A709B77.9080209@ieee.org>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com> 
	<4A709B77.9080209@ieee.org>
Message-ID: <77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>

Hi Dave,

Thanks for your reply. I actually didn't cut and paste my code as it was
dispersed in different places, i typed the logic behind my code in the email
(and obiviously made some typos, indentations is some thing else) but my
real code does not have these problems as my application runs fine with out
errors...

Except that the line where i want to update the value doesn't get updated
and no exception is thrown. What's surprising for me is that i am doing the
same thing in hundreds of places in my 3k+ line code but by some reason this
part doesn't work...

As far as the global variables are concerned, i am using them in other
places too and didn't see any problems.

I think some thing else is going on here as the statement above and below my
modified lines get executed.

Is there a way in Python to debug memory address or to see where in memory
this object is stored, and is there a lock on it or else?

Thanks,
Omer


**************************************


On Wed, Jul 29, 2009 at 8:56 PM, Dave Angel <davea at ieee.org> wrote:

> Omer Khalid wrote:
>
>> Hi,
>>
>> I am having a very strange problem with modifying a variable in a list in
>> my
>> program. Here is the code:
>>
>> # a list that contains dictionary objects
>> jobs = []
>>
>> index=5
>> for each in range(index):
>>         jobs.append({'v':0})
>>
>> some_function(index):
>>       if jobs[index]['v'] == 0:
>>                   # set it to 1
>>                   jobs[index]['v'] = 1
>>                   print "Set to 1"
>>      else:
>>                   print "Already set to 1"
>>
>> loop():
>>        index=0
>>        for each in range(len(jobs)):
>>                 some_function(index)
>>                 index +=1
>>
>>
>> Apparently, the jobs[index]['v'] never get updated in the some_function
>> but
>> the print statement afterwards get printed...
>>
>> What's really surprising is that there are no errors or exceptions and my
>> my
>> program runs in a single thread...so i have been unable to explain this
>> behavior.
>>
>> Any insight would be much appreciated!
>>
>> Cheers
>> Omer
>>
>>
>>
> There are four things to fix before the program does anything much at all.
>  Two places you're missing the def, indentation is inconsistent, and you
> never actually call either of the functions.   The first three are syntax
> errors, so presumably your cut/paste in your computer is broken.
>
> Once I make those four corrections, I get the following output:
>
> Set to 1
> Set to 1
> Set to 1
> Set to 1
> Set to 1
>
> But you never said what you got, nor what you expected.  That's certainly
> what I'd expect.  And if you make a second call to loop() in your outer
> code, you get five copies of "Already set to 1"
>
> BTW, there are a number of things that could be done better.  The main one
> I'll point out is that you shouldn't re-use a global variable 'index' as a
> local with different meaning.  As someone else pointed out, since the global
> is a constant, making it all uppercase is the convention.
>
> DaveA
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/11d04716/attachment.html>

From darkneter at gmail.com  Wed Jul 29 15:32:10 2009
From: darkneter at gmail.com (NighterNet)
Date: Wed, 29 Jul 2009 12:32:10 -0700 (PDT)
Subject: simple splash screen?
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
	<LYudnbbBM-OdD-3XnZ2dnUVZ8opi4p2d@bt.com>
Message-ID: <79954da5-a437-48a1-985b-88abe601d021@a37g2000prf.googlegroups.com>

On Jul 29, 11:16?am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
wrote:
> NighterNet wrote:
> > I am trying to make a simple splash screen from python 3.1.Not sure
> > where to start looking for it. Can any one help?
>
> Sure, almost the same as with Python 2 :-)
> But to be a bit more specific:
> ++++
> """Only works if you got Python 3 installed with tkinter"""
> import tkinter
>
> IMAGE_PATH = "/path/to/image"
>
> class Splash(object):
> ? ? ?"Splash Screen GUI"
> ? ? ?def __init__(self, root):
> ? ? ? ? ?self.root = root
> ? ? ? ? ?# No window borders and decoration
> ? ? ? ? ?self.root.overrideredirect(True)
> ? ? ? ? ?# Get the size of the screen
> ? ? ? ? ?screen_width = self.root.winfo_screenwidth()
> ? ? ? ? ?screen_height = self.root.winfo_screenheight()
> ? ? ? ? ?# Full screen
> ? ? ? ? ?geometry_text = "%dx%d+0+0" % (screen_width, screen_height)
> ? ? ? ? ?self.root.geometry(geometry_text)
> ? ? ? ? ?# Display an image
> ? ? ? ? ?self.label = tkinter.Label(self.root)
> ? ? ? ? ?# Only GIF and PGM/PPM supported, for more information see:
> ? ? ? ? ?self.label._image = tkinter.PhotoImage(file=IMAGE_PATH)
> ? ? ? ? ?#http://effbot.org/tkinterbook/photoimage.htm
> ? ? ? ? ?self.label.configure(image = self.label._image)
> ? ? ? ? ?self.label.pack()
> ? ? ? ? ?# This will quit the screen after about 5 seconds
> ? ? ? ? ?self.root.after(5000, self.root.quit)
>
> if __name__ == '__main__':
> ? ? ?ROOT = tkinter.Tk()
> ? ? ?APPL = Splash(ROOT)
> ? ? ?ROOT.mainloop()
> ++++
>
> --
> MPHhttp://blog.dcuktec.com
> 'If consumed, best digested with added seasoning to own preference.'

Thanks it help. Sorry about that, I was just wander what kind of
answer and if there are other methods to learn it.

Is there a way to position image to the center screen?


From tjreedy at udel.edu  Wed Jul 29 15:41:34 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 29 Jul 2009 15:41:34 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
Message-ID: <h4q8ld$8hc$1@ger.gmane.org>

Omer Khalid wrote:
> Hi,
> 
> I am having a very strange problem with modifying a variable in a list 
> in my program. Here is the code:

To me, this sentence clearly implies that the code that follows is the 
code that had the problem. Since the posted code cannot run, it clearly 
is not. People should test code to be posted before posting unless they 
clearly label it as 'untested'. Original posters, of course, should run 
the code first.

tjr



From davea at ieee.org  Wed Jul 29 15:42:39 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 15:42:39 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
	<4A709B77.9080209@ieee.org>
	<77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
Message-ID: <4A70A62F.6080403@ieee.org>

Omer Khalid wrote:
> Hi Dave,
>
> Thanks for your reply. I actually didn't cut and paste my code as it was
> dispersed in different places, i typed the logic behind my code in the email
> (and obiviously made some typos, indentations is some thing else) but my
> real code does not have these problems as my application runs fine with out
> errors...
>
> Except that the line where i want to update the value doesn't get updated
> and no exception is thrown. What's surprising for me is that i am doing the
> same thing in hundreds of places in my 3k+ line code but by some reason this
> part doesn't work...
>
> As far as the global variables are concerned, i am using them in other
> places too and didn't see any problems.
>
> I think some thing else is going on here as the statement above and below my
> modified lines get executed.
>
> Is there a way in Python to debug memory address or to see where in memory
> this object is stored, and is there a lock on it or else?
>
> Thanks,
> Omer
>
>
> **************************************
>
>
> On Wed, Jul 29, 2009 at 8:56 PM, Dave Angel <davea at ieee.org> wrote:
>
>   
>> Omer Khalid wrote:
>>
>>     
>>> Hi,
>>>
>>> I am having a very strange problem with modifying a variable in a list in
>>> my
>>> program. Here is the code:
>>>
>>> # a list that contains dictionary objects
>>> jobs = []
>>>
>>> index=5
>>> for each in range(index):
>>>         jobs.append({'v':0})
>>>
>>> some_function(index):
>>>       if jobs[index]['v'] == 0:
>>>                   # set it to 1
>>>                   jobs[index]['v'] = 1
>>>                   print "Set to 1"
>>>      else:
>>>                   print "Already set to 1"
>>>
>>> loop():
>>>        index=0
>>>        for each in range(len(jobs)):
>>>                 some_function(index)
>>>                 index +=1
>>>
>>>
>>> Apparently, the jobs[index]['v'] never get updated in the some_function
>>> but
>>> the print statement afterwards get printed...
>>>
>>> What's really surprising is that there are no errors or exceptions and my
>>> my
>>> program runs in a single thread...so i have been unable to explain this
>>> behavior.
>>>
>>> Any insight would be much appreciated!
>>>
>>> Cheers
>>> Omer
>>>
>>>
>>>
>>>       
>> There are four things to fix before the program does anything much at all.
>>  Two places you're missing the def, indentation is inconsistent, and you
>> never actually call either of the functions.   The first three are syntax
>> errors, so presumably your cut/paste in your computer is broken.
>>
>> Once I make those four corrections, I get the following output:
>>
>> Set to 1
>> Set to 1
>> Set to 1
>> Set to 1
>> Set to 1
>>
>> But you never said what you got, nor what you expected.  That's certainly
>> what I'd expect.  And if you make a second call to loop() in your outer
>> code, you get five copies of "Already set to 1"
>>
>> BTW, there are a number of things that could be done better.  The main one
>> I'll point out is that you shouldn't re-use a global variable 'index' as a
>> local with different meaning.  As someone else pointed out, since the global
>> is a constant, making it all uppercase is the convention.
>>
>> DaveA
>>
>>     
(You top-posted, so your ,message is out of sequence.  More and more 
people are doing that in this list.)


++++  ...Except that the line where i want to update the value doesn't 
get updated...

And what makes you think that?  You never answered my question.  What did you expect for output, and what did you get?  I got exactly what I expected, when I ran it.

++++ ...  Is there a way in Python to debug memory address or
++++      to see where in memory this object is stored, and
++++      is there a lock on it or else?

If there really were a bug in the language, you might need such a tool.  
I use Komodo IDE as a debugger, but there was no need in this case.  
Adding a few print statements might clear up your confusion, but since 
you haven't spelled out what it is, I can't suggest where.  How about if 
you just add a    print jobs    at the beginning of some_function() ?  
Then you could see things getting updated perfectly.

DaveA



From zuo at chopin.edu.pl  Wed Jul 29 15:54:51 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Wed, 29 Jul 2009 21:54:51 +0200
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
Message-ID: <op.uxuhlpetfvx12t@jerzozwiesz.home.aster.pl>

29-07-2009 Benjamin Kaplan <benjamin.kaplan at case.edu> wrote:

> On Wed, Jul 29, 2009 at 1:59 PM, dandi kain <dandi.kain at gmail.com> wrote:
[snip
>> What is the functionality of __ or _ , leading or trailing an object ,
>> class ot function ? Is it just a naming convention to note special
>> functions and objects , or it really mean someting to Python ?
>
> It's just a convention for the most part. A single leading underscore
> is used for "private" attributes. Two leading underscores will affect
> the code-

Single leading underscore in some situations also affect the code...

See:

*  
http://docs.python.org/reference/lexical_analysis.html#reserved-classes-of-identifiers

* http://docs.python.org/reference/datamodel.html#object.__del__
   (in the the red "Warning" frame)

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From tjreedy at udel.edu  Wed Jul 29 15:57:25 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 29 Jul 2009 15:57:25 -0400
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
Message-ID: <h4q9j5$bjf$1@ger.gmane.org>

Benjamin Kaplan wrote:
> On Wed, Jul 29, 2009 at 1:59 PM, dandi kain <dandi.kain at gmail.com> wrote:
>> Hello everybody,
>> I have just started learning Python.I heard its simple so I pick a
>> presentation [1] and tried to work on it.But when it comes to
>> underscores leading and trailing an object I dont understand any.I
>> look through the python manual also but that was not helping .I
>> searched some forums and I still dont have a clear picture.
>>
>> What is the functionality of __ or _ , leading or trailing an object ,
>> class ot function ? Is it just a naming convention to note special
>> functions and objects , or it really mean someting to Python ?
> 
> It's just a convention for the most part. A single leading underscore
> is used for "private" attributes. Two leading underscores will affect
> the code- it mangles the variable name so that you don't have to worry
> about the value being overwritten by a subclass. For instance
> """
> class Foo(object) :
>    def __init__(self) :
>        self.__bar = ''
> 
> foo = Foo()
> ""
> will store the attribute as foo._Foo__bar.
> 
> Also, the "magic methods"- the ones that are used for operations and
> built-in stuff, all have two leading and two trailing underscores.
> These are things like __add__ (+), __eq__ (=), __cmp__ (old way for
> comparisons), __len__ (len), __str__ (str), and so on.

For this last, see
http://docs.python.org/dev/py3k/reference/datamodel.html#special-method-names



From no.email at please.post  Wed Jul 29 16:05:36 2009
From: no.email at please.post (kj)
Date: Wed, 29 Jul 2009 20:05:36 +0000 (UTC)
Subject: How to "gunzip-iterate" over a file?
Message-ID: <h4qa2g$i5v$1@reader1.panix.com>




I need to iterate over the lines of *very* large (>1 GB) gzipped
files.  I would like to do this without having to read the full
compressed contents into memory so that I can apply zlib.decompress
to these contents.  I also would like to avoid having to gunzip
the file (i.e. creating an uncompressed version of the file in the
filesystem) prior to iterating over it.

Basically I'm looking for something that will give me the same
functionality as Perl's gzip IO layer, which looks like this (from
the documentation):

         use PerlIO::gzip;
         open FOO, "<:gzip", "file.gz" or die $!;
         print while <FOO>; # And it will be uncompressed...

What's the best way to achieve the same functionality in Python?

TIA!

kynn


From malc0de.encrypt at gmail.com  Wed Jul 29 16:21:56 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Wed, 29 Jul 2009 13:21:56 -0700 (PDT)
Subject: Does python have the capability for driver development ?
Message-ID: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>

hello there, I've a question :
I want to know does python have any capability for using Ring0 and
kernel functions for driver and device development stuff .
if there's such a feature it is very good, and if there something for
this kind that you know please refer me to some reference and show me
some snippet .

thanks

- Malc0de


From robert.kern at gmail.com  Wed Jul 29 16:22:43 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 29 Jul 2009 15:22:43 -0500
Subject: How to "gunzip-iterate" over a file?
In-Reply-To: <h4qa2g$i5v$1@reader1.panix.com>
References: <h4qa2g$i5v$1@reader1.panix.com>
Message-ID: <h4qb2j$fck$1@ger.gmane.org>

On 2009-07-29 15:05, kj wrote:
>
>
> I need to iterate over the lines of *very* large (>1 GB) gzipped
> files.  I would like to do this without having to read the full
> compressed contents into memory so that I can apply zlib.decompress
> to these contents.  I also would like to avoid having to gunzip
> the file (i.e. creating an uncompressed version of the file in the
> filesystem) prior to iterating over it.
>
> Basically I'm looking for something that will give me the same
> functionality as Perl's gzip IO layer, which looks like this (from
> the documentation):
>
>           use PerlIO::gzip;
>           open FOO, "<:gzip", "file.gz" or die $!;
>           print while<FOO>; # And it will be uncompressed...
>
> What's the best way to achieve the same functionality in Python?

http://docs.python.org/library/gzip

import gzip

f = gzip.open('filename.gz')
for line in f:
     print line
f.close()

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From npuloski at gmail.com  Wed Jul 29 16:23:33 2009
From: npuloski at gmail.com (Nanime Puloski)
Date: Wed, 29 Jul 2009 16:23:33 -0400
Subject: Differences Between Arrays and Matrices in Numpy
Message-ID: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>

What are some differences between arrays and matrices using the Numpy
library? When would I want to use arrays instead of matrices and vice
versa?


From pfeldman at verizon.net  Wed Jul 29 16:26:23 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Wed, 29 Jul 2009 13:26:23 -0700 (PDT)
Subject: delayed sys.exit?
Message-ID: <24726902.post@talk.nabble.com>


In the attached  http://www.nabble.com/file/p24726902/test.py test.py code,
it appears that additional statements execute after the call to sys.exit(0). 
I'll be grateful if anyone can shed light on why this is happening.  Below
is a copy of some sample I/O.  Note that in the last case I get additional
output after what should be the final error message.

In [126]: run test
Input a string: 1,2
[1, 2]

In [127]: run test
Input a string: 1-3
[1, 2, 3]

In [128]: run test
Input a string: 1,4,5-12
[1, 4, 5, 6, 7, 8, 9, 10, 11, 12]

In [129]: run test
Input a string: 0
ERROR: 0 is invalid; run numbers must be positive.
ERROR: '0' is not a valid run number.


-- 
View this message in context: http://www.nabble.com/delayed-sys.exit--tp24726902p24726902.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From james at agentultra.com  Wed Jul 29 16:33:11 2009
From: james at agentultra.com (J Kenneth King)
Date: Wed, 29 Jul 2009 16:33:11 -0400
Subject: escaping characters in filenames
References: <854osv7h2k.fsf@agentultra.com>
	<pan.2009.07.29.18.55.16.468000@nowhere.com>
Message-ID: <85ws5r5iwo.fsf@agentultra.com>

Nobody <nobody at nowhere.com> writes:

> On Wed, 29 Jul 2009 09:29:55 -0400, J Kenneth King wrote:
>
>> I wrote a script to process some files using another program.  One thing
>> I noticed was that both os.listdir() and os.path.walk() will return
>> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
>> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
>> module or recipe that escapes file names and was wondering if anyone
>> could point me in the right direction.
>> 
>> As an aside, the script is using subprocess.call() with the "shell=True"
>> parameter.  There isn't really a reason for doing it this way (was just
>> the fastest way to write it and get a prototype working).  I was
>> wondering if Popen objects were sensitive to unescaped names like the
>> shell.  I intend to refactor the function to use Popen objects at some
>> point and thought perhaps escaping file names may not be entirely
>> necessary.
>
> Note that subprocess.call() is nothing more than:
>
> 	def call(*popenargs, **kwargs):
> 	    return Popen(*popenargs, **kwargs).wait()
>
> plus a docstring. It accepts exactly the same arguments as Popen(), with
> the same semantics.
>
> If you want to run a command given a program and arguments, you
> should pass the command and arguments as a list, rather than trying to
> construct a string.
>
> On Windows the value of shell= is unrelated to whether the command is
> a list or a string; a list is always converted to string using the
> list2cmdline() function. Using shell=True simply prepends "cmd.exe /c " to
> the string (this allows you to omit the .exe/.bat/etc extension for
> extensions which are in %PATHEXT%).
>
> On Unix, a string is first converted to a single-element list, so if you
> use a string with shell=False, it will be treated as the name of an
> executable to be run without arguments, even if contains spaces, shell
> metacharacters etc.
>
> The most portable approach seems to be to always pass the command as a
> list, and to set shell=True on Windows and shell=False on Unix.
>
> The only reason to pass a command as a string is if you're getting a
> string from the user and you want it to be interpreted using the
> platform's standard shell (i.e. cmd.exe or /bin/sh). If you want it to be
> interpreted the same way regardless of platform, parse it into a
> list using shlex.split().

I understand; I think I was headed towards subprocess.Popen() either
way.  It seems to handle the problem I posted about.  And I got to learn
a little something on the way.  Thanks!

Only now there's a new problem in that the output of the program is
different if I run it from Popen than if I run it from the command line.
The program in question is 'pdftotext'.  More investigation to ensue.

Thanks again for the helpful post.


From robert.kern at gmail.com  Wed Jul 29 16:36:03 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 29 Jul 2009 15:36:03 -0500
Subject: Differences Between Arrays and Matrices in Numpy
In-Reply-To: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>
References: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>
Message-ID: <h4qbro$jl2$1@ger.gmane.org>

On 2009-07-29 15:23, Nanime Puloski wrote:
> What are some differences between arrays and matrices using the Numpy
> library? When would I want to use arrays instead of matrices and vice
> versa?

You will want to ask numpy questions on the numpy mailing list:

   http://www.scipy.org/Mailing_Lists

An overview of how the matrix subclass differs from ndarray, see the documentation:

   http://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects

Basically, I suggest that you just use regular arrays always. There is a 
syntactical convenience to matrix objects, but it does cause incompatibilities 
with the majority of code that is written for regular arrays. The convenience is 
usually not worth the cost.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From apt.shansen at gmail.com  Wed Jul 29 16:36:32 2009
From: apt.shansen at gmail.com (Stephen Hansen)
Date: Wed, 29 Jul 2009 13:36:32 -0700
Subject: delayed sys.exit?
In-Reply-To: <24726902.post@talk.nabble.com>
References: <24726902.post@talk.nabble.com>
Message-ID: <7a9c25c20907291336k5b4686c9sb410710967307907@mail.gmail.com>

>
> In the attached  http://www.nabble.com/file/p24726902/test.py test.py
> code,
> it appears that additional statements execute after the call to
> sys.exit(0).
> I'll be grateful if anyone can shed light on why this is happening.  Below
> is a copy of some sample I/O.  Note that in the last case I get additional
> output after what should be the final error message.
>

A bare "except:" catches ALL exceptions; including SystemExit which is
generated by
sys.exit. And KeyboardInterrupt, too. That's why its basically a bad
idea to use bare excepts unless you really, really, really need to.
Try 'except Exception' instead. SystemExit and such do not inherit
from Exception.

--S
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/89114fbe/attachment.html>

From __peter__ at web.de  Wed Jul 29 16:40:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 29 Jul 2009 22:40:13 +0200
Subject: delayed sys.exit?
References: <mailman.3918.1248899186.8015.python-list@python.org>
Message-ID: <h4qc32$as8$02$1@news.t-online.com>

Dr. Phillip M. Feldman wrote:

> In the attached  http://www.nabble.com/file/p24726902/test.py test.py
> code, it appears that additional statements execute after the call to
> sys.exit(0).

>    try:
>       # If the conversion to int fails, nothing is appended to the list:
>       Runs.append(int(strs[i]))
>       if Runs[-1] <= 0:
>          print 'ERROR: ' + str(Runs[-i]) + \
>            ' is invalid; run numbers must be positive.'
>          sys.exit(0)
>    except:

sys.exit() works by raising a SystemExit exception which is caught by the 
bare except.

http://docs.python.org/library/sys.html#sys.exit
http://docs.python.org/library/exceptions.html#exceptions.SystemExit

As a general rule try to be as specific as possible when catching 
exceptions.

Peter



From python at mrabarnett.plus.com  Wed Jul 29 16:41:37 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 21:41:37 +0100
Subject: delayed sys.exit?
In-Reply-To: <24726902.post@talk.nabble.com>
References: <24726902.post@talk.nabble.com>
Message-ID: <4A70B401.9040700@mrabarnett.plus.com>

Dr. Phillip M. Feldman wrote:
> In the attached  http://www.nabble.com/file/p24726902/test.py test.py code,
> it appears that additional statements execute after the call to sys.exit(0). 
> I'll be grateful if anyone can shed light on why this is happening.  Below
> is a copy of some sample I/O.  Note that in the last case I get additional
> output after what should be the final error message.
> 
> In [126]: run test
> Input a string: 1,2
> [1, 2]
> 
> In [127]: run test
> Input a string: 1-3
> [1, 2, 3]
> 
> In [128]: run test
> Input a string: 1,4,5-12
> [1, 4, 5, 6, 7, 8, 9, 10, 11, 12]
> 
> In [129]: run test
> Input a string: 0
> ERROR: 0 is invalid; run numbers must be positive.
> ERROR: '0' is not a valid run number.
> 
sys.exit raises an SystemExit exception, which then gets caught by the
bare 'except' of the enclosing try...except... statement.

A lot of things can raise an exception, which is why bare 'except's are
a bad idea; catch only those you expect.


From Russ.Davis at njpines.state.nj.us  Wed Jul 29 16:55:27 2009
From: Russ.Davis at njpines.state.nj.us (Russ Davis)
Date: Wed, 29 Jul 2009 16:55:27 -0400
Subject: IDLE Config Problems
Message-ID: <4A70801E.DEDA.009D.0@njpines.state.nj.us>

I am just getting started with Python and have installed v. 2.5.4  Idle version 1.2.4  I can't seem to get the idle to display text.  It seems as if the install went fine.  I start up the idle and the screen is blank.  No text.  It seems as if I can type on the screen but I just can't see the characters.   I go to the config menu and it bombs and brings up the Visual Studio debugger.  The computer that I am trying to install it on is a windows xp laptop serv pack 2.   I have a workstation here that I am using also with the same os and the idle works fine.  Any hints as to what might be interfering with the idle config.

Thanks

Russ

Russell Davis PP, AICP, GISP
GIS Administrator
State of New Jersey Pinelands Commission
Office of Land Use and Technology
GIS Laboratory
Po Box 7
New Lisbon, NJ 08064
Phone 609-894-7300
Fax 609-894-7330
russ.davis at njpines.state.nj.us



From __peter__ at web.de  Wed Jul 29 17:06:30 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 29 Jul 2009 23:06:30 +0200
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <h4qdkb$2pm$00$1@news.t-online.com>

Martin wrote:

> I am trying to set the return value from a function to a name which I
> grab from the for loop. I can't work out how I can do this without
> using an if statement...
> 
> for f in var1_fn, var2_fn, var3_fn:
>     if f.split('.')[0] == 'var1':
>         var1 = call_some_function(f)
> .
>         .
>         .
>       etc
> 
>  Really I would like to remove the need for this if loop and I am sure
> there is a simple way I am missing?

Use dictionaries:

functions = {"var1": some_function, "var2": some_other_function, ...} 
return_values = {}

for arg in var1_fn, var2_fn, var3_fn:
    key = arg.split(".")[0]
    return_values[key] = functions[key](arg)

Peter



From martin.hellwig at dcuktec.org  Wed Jul 29 17:08:23 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Wed, 29 Jul 2009 22:08:23 +0100
Subject: simple splash screen?
In-Reply-To: <79954da5-a437-48a1-985b-88abe601d021@a37g2000prf.googlegroups.com>
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
	<LYudnbbBM-OdD-3XnZ2dnUVZ8opi4p2d@bt.com>
	<79954da5-a437-48a1-985b-88abe601d021@a37g2000prf.googlegroups.com>
Message-ID: <se-dndtmZ63UJ-3XnZ2dnUVZ8n1i4p2d@bt.com>

NighterNet wrote:
<cut>
> Thanks it help. Sorry about that, I was just wander what kind of
> answer and if there are other methods to learn it.
> 
> Is there a way to position image to the center screen?

Yes there is, just start reading from here:
http://effbot.org/tkinterbook/

Though because Python 3 has done some module reorganisation/renaming, 
Tkinter is now called tkinter.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From deets at nospam.web.de  Wed Jul 29 17:11:49 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 29 Jul 2009 23:11:49 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
Message-ID: <7dbs8nF2br07nU1@mid.uni-berlin.de>

MalC0de schrieb:
> hello there, I've a question :
> I want to know does python have any capability for using Ring0 and
> kernel functions for driver and device development stuff .
> if there's such a feature it is very good, and if there something for
> this kind that you know please refer me to some reference and show me
> some snippet .

No, it can't do such things. At least it isn't embedded in the kernel - 
in theory that might be possible, but given the timing-constraints and 
concurrency-requirements, it's not really feasible.

Diez


From bearophileHUGS at lycos.com  Wed Jul 29 17:12:34 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Wed, 29 Jul 2009 14:12:34 -0700 (PDT)
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <eefa9f4d-b763-41da-9be5-9caedc11ba63@d4g2000yqa.googlegroups.com>

Martin:
> for f in var1_fn, var2_fn, var3_fn:
> ? ? if f.split('.')[0] == 'var1':
> ? ? ? ? var1 = call_some_function(f)
> ? ? ? ? .
> ? ? ? ? .
> ? ? ? ? .
> ? ? ? etc

As usual I have big problems in understanding what you want to do.

Please, show an example of the contents of var1_fn, var2_fn, etc.

Generally you can create a dict:
results = {}

And then fill it with name-result pairs:
name = value.split('_')[0]
results[name] = some_function(value)

Bye,
bearophile


From andre.roberge at gmail.com  Wed Jul 29 17:18:52 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Wed, 29 Jul 2009 14:18:52 -0700 (PDT)
Subject: how to embed the python interpreter into web App (Mehndi, Sibtey)
References: <mailman.14496.1248881699.8014.python-list@python.org> 
	<mailman.3901.1248885631.8015.python-list@python.org>
Message-ID: <4c2f2ee0-1009-4dc7-8cd7-b38db43d83c7@o32g2000yqm.googlegroups.com>

On Jul 29, 1:11?pm, Ryniek90 <rynie... at gmail.com> wrote:
> > Hi All
>
> > I am trying to embed the python interpreter in to a web app but could
> > not get the way, any one can suggest me how to do this.
>
> > Thanks,
>
> > Sibtey Mehdi
>
> > This e-mail (and any attachments), is confidential and may be privileged. It may be read, copied and used only
> > by intended recipients. Unauthorized access to this e-mail (or attachments) and disclosure or copying of its
> > contents or any action taken in reliance on it is unlawful. Unintended recipients must notify the sender immediately
> > by e-mail/phone & delete it from their system without making any copies or disclosing it to a third person.
>
> Here's example:http://try-python.mired.org/
>
> Contact with author of that website/webapp.
>
> Good luck.

Or you can look at the code for Crunchy: http://code.google.com/p/crunchy

Note however that this will result in something that is not secure...
To quote the try-python site:

"My ISP (idiom.com) provides a sandbox inside a FreeBSD Jail..."

Andr?


From davea at ieee.org  Wed Jul 29 17:47:43 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 17:47:43 -0400
Subject: set variable to looping index?
In-Reply-To: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <4A70C37F.2030709@ieee.org>

Martin wrote:
> Hi,
>
> I am trying to set the return value from a function to a name which I
> grab from the for loop. I can't work out how I can do this without
> using an if statement...
>
> for f in var1_fn, var2_fn, var3_fn:
>     if f.split('.')[0] == 'var1':
>         var1 = call_some_function(f)
> 	.
>         .
>         .
>       etc
>
>  Really I would like to remove the need for this if loop and I am sure
> there is a simple way I am missing?
>
> Many thanks
>
> Martin
>
>   

Is this a real problem, or is it a "programming puzzle"?   If it's the 
latter, maybe someone else can help.

But if it's a real problem, give us some context, and maybe we can 
figure out how to help.

If I took this fragment at face value, I'd simply replace it by:

var1 = call_some_function(var1_fn)
var2 = call_some_function(var2_fn)
var3 = call_some_function(var3_fn)


Is this fragment part of a function definition, or is it top-level?  Are 
there really exactly three var*_fn objects, or might there be an 
arbitrary number of them?   Do you want to tell us the types of these 
three objects?  Is there content really tied directly to their name?  
Did they get their values from literals, or were they computed at some 
other point?


DaveA


From rhodri at wildebst.demon.co.uk  Wed Jul 29 18:02:00 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 29 Jul 2009 23:02:00 +0100
Subject: set variable to looping index?
In-Reply-To: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <op.uxunhmr1a8ncjz@gnudebst>

On Wed, 29 Jul 2009 19:56:28 +0100, Martin <mdekauwe at gmail.com> wrote:

> Hi,
>
> I am trying to set the return value from a function to a name which I
> grab from the for loop. I can't work out how I can do this without
> using an if statement...
>
> for f in var1_fn, var2_fn, var3_fn:
>     if f.split('.')[0] == 'var1':
>         var1 = call_some_function(f)
> 	.
>         .
>         .
>       etc
>
>  Really I would like to remove the need for this if loop and I am sure
> there is a simple way I am missing?

It's a little hard to tell what you actually want from your description,
but it looks like you're fighting the language unnecessarily here.  If
you have a sequence of functions that you want a sequence of results
out of, you should be thinking in terms of a sequence type.  A list,
in other words.

results = []
for f in fn1, fn2, fn3:
     results.append(f())


-- 
Rhodri James *-* Wildebeest Herder to the Masses


From nobody at nowhere.com  Wed Jul 29 18:21:27 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 23:21:27 +0100
Subject: Differences Between Arrays and Matrices in Numpy
References: <mailman.3917.1248899015.8015.python-list@python.org>
Message-ID: <pan.2009.07.29.22.21.27.546000@nowhere.com>

On Wed, 29 Jul 2009 16:23:33 -0400, Nanime Puloski wrote:

> What are some differences between arrays and matrices using the Numpy
> library?

Matrices are always two-dimensional, as are slices of them. Matrices
override mulitplication and exponentiation to use matrix multiplication
rather than element-wise multiplication.

> When would I want to use arrays instead of matrices and vice
> versa?

Use a matrix if you want a matrix, i.e. a linear transformation.
Otherwise, use an array.



From mdekauwe at gmail.com  Wed Jul 29 18:29:30 2009
From: mdekauwe at gmail.com (Martin)
Date: Wed, 29 Jul 2009 15:29:30 -0700 (PDT)
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
Message-ID: <0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>

On Jul 29, 11:02?pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
wrote:
> On Wed, 29 Jul 2009 19:56:28 +0100, Martin <mdeka... at gmail.com> wrote:
> > Hi,
>
> > I am trying to set the return value from a function to a name which I
> > grab from the for loop. I can't work out how I can do this without
> > using an if statement...
>
> > for f in var1_fn, var2_fn, var3_fn:
> > ? ? if f.split('.')[0] == 'var1':
> > ? ? ? ? var1 = call_some_function(f)
> > ? ?.
> > ? ? ? ? .
> > ? ? ? ? .
> > ? ? ? etc
>
> > ?Really I would like to remove the need for this if loop and I am sure
> > there is a simple way I am missing?
>
> It's a little hard to tell what you actually want from your description,
> but it looks like you're fighting the language unnecessarily here. ?If
> you have a sequence of functions that you want a sequence of results
> out of, you should be thinking in terms of a sequence type. ?A list,
> in other words.
>
> results = []
> for f in fn1, fn2, fn3:
> ? ? ?results.append(f())
>
> --
> Rhodri James *-* Wildebeest Herder to the Masses

Hi all,

Thanks and apologises I wasn't trying to be cryptic, like all things
when I wrote it I thought it was quite transparent.

All I was trying to do was call a function and return the result to an
a variable. I could admittedly of just done...

var1 = some_function(var1_fn)
var2 = some_function(var2_fn)
var3 = some_function(var3_fn)

where var1_fn, var2_fn, var3_fn are just filenames, e.g. var1_fn =
'x.txt'. But I figured I would try and make it slightly more generic
whilst I was at it, hence my attempt to use the filenames to create
the variable names (hence the loop). I will as suggested try the
dictionary option. I appreciate all the suggestions.

Thanks

Martin


From nick at craig-wood.com  Wed Jul 29 18:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Wed, 29 Jul 2009 17:29:56 -0500
Subject: Does python have the capability for driver development ?
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<7dbs8nF2br07nU1@mid.uni-berlin.de>
Message-ID: <slrnh71g6g.djc.nick@irishsea.home.craig-wood.com>

Diez B. Roggisch <deets at nospam.web.de> wrote:
>  MalC0de schrieb:
> > hello there, I've a question :
> > I want to know does python have any capability for using Ring0 and
> > kernel functions for driver and device development stuff .
> > if there's such a feature it is very good, and if there something for
> > this kind that you know please refer me to some reference and show me
> > some snippet .
> 
>  No, it can't do such things. At least it isn't embedded in the kernel - 
>  in theory that might be possible, but given the timing-constraints and 
>  concurrency-requirements, it's not really feasible.

You can write FUSE (file systems in userspace) drivers in python I believe.
Not the same as running in ring0 but in most senses a kernel driver...

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From pavlovevidence at gmail.com  Wed Jul 29 18:55:26 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 29 Jul 2009 15:55:26 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com> 
	<m2fxcfefu2.fsf@cs.uu.nl>
Message-ID: <8cb1ba65-be71-49b7-8955-54c17f351a40@w6g2000yqw.googlegroups.com>

On Jul 29, 7:14?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Carl Banks <pavlovevide... at gmail.com> (CB) wrote:
> >CB> On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
> >>> I'm looking to run a process with a limit of 3 instances, but each
> >>> execution is over a crontab interval. I've been investigating the
> >>> threading module and using daemons to limit active thread objects, but
> >>> I'm not very successful at grasping the documentation.
>
> >>> Is it possible to do what I'm trying to do and if so anyone know of a
> >>> useful example to get started?
> >CB> It seems like you want to limit the number of processes to three; the
> >CB> threading module won't help you there because it deals with threads
> >CB> within a single process.
> >CB> What I'd do is to simply run the system ps to see how many processes
> >CB> are running (ps is pretty versatile on most systems and can find
> >CB> specifically targeted processes like you program), and exit if there
> >CB> are already three.
>
> That will surely run into some race conditions.

What, the OS might not have gotten around to update the process table
to include a process started minutes ago?  (He said he was starting
the processes over crontab intervals, not that he communicated what he
wanted well.)


Carl Banks


From zuo at chopin.edu.pl  Wed Jul 29 18:57:02 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 00:57:02 +0200
Subject: set variable to looping index?
In-Reply-To: <0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
	<0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
Message-ID: <op.uxup1cxjfvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 <mdekauwe at gmail.com> wrote:

> All I was trying to do was call a function and return the result to an
> a variable. I could admittedly of just done...
>
> var1 = some_function(var1_fn)
> var2 = some_function(var2_fn)
> var3 = some_function(var3_fn)
>
> where var1_fn, var2_fn, var3_fn are just filenames, e.g. var1_fn =
> 'x.txt'. But I figured I would try and make it slightly more generic
> whilst I was at it, hence my attempt to use the filenames to create
> the variable names (hence the loop).

Hi,

Then you could also consider using simply lists:

filenames = p'foo', 'bar', baz']
results = []
for name in filenames:
     results.append(some_function(name))

If filenames were generated according to a particular pattern, you can
mimic that pattern and generate filenames list using
list-comprehension, e.g.:

filenames = ['file{nr}.txt'.format(nr=nr) for nr in range(13)]

Chreers,

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From zuo at chopin.edu.pl  Wed Jul 29 19:03:33 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 01:03:33 +0200
Subject: set variable to looping index?
In-Reply-To: <op.uxup1cxjfvx12t@jerzozwiesz.home.aster.pl>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
	<0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
	<op.uxup1cxjfvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <op.uxuqb7a6fvx12t@jerzozwiesz.home.aster.pl>

Me wrote:

> filenames = p'foo', 'bar', baz']

Sorry, should be of course:

filenames = ['foo', 'bar', baz']

*j
-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From mdekauwe at gmail.com  Wed Jul 29 19:04:59 2009
From: mdekauwe at gmail.com (Martin)
Date: Wed, 29 Jul 2009 16:04:59 -0700 (PDT)
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
	<0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
	<mailman.3925.1248908229.8015.python-list@python.org>
Message-ID: <a0c47f56-6259-4c32-8c25-7efb93dddb08@32g2000yqj.googlegroups.com>

On Jul 29, 11:57?pm, "Jan Kaliszewski" <z... at chopin.edu.pl> wrote:
> 30-07-2009 <mdeka... at gmail.com> wrote:
> > All I was trying to do was call a function and return the result to an
> > a variable. I could admittedly of just done...
>
> > var1 = some_function(var1_fn)
> > var2 = some_function(var2_fn)
> > var3 = some_function(var3_fn)
>
> > where var1_fn, var2_fn, var3_fn are just filenames, e.g. var1_fn =
> > 'x.txt'. But I figured I would try and make it slightly more generic
> > whilst I was at it, hence my attempt to use the filenames to create
> > the variable names (hence the loop).
>
> Hi,
>
> Then you could also consider using simply lists:
>
> filenames = p'foo', 'bar', baz']
> results = []
> for name in filenames:
> ? ? ?results.append(some_function(name))
>
> If filenames were generated according to a particular pattern, you can
> mimic that pattern and generate filenames list using
> list-comprehension, e.g.:
>
> filenames = ['file{nr}.txt'.format(nr=nr) for nr in range(13)]
>
> Chreers,
>
> *j
>
> --
> Jan Kaliszewski (zuo) <z... at chopin.edu.pl>

I guess I wanted to keep the function returns in separate arrays in
this case, hence my attempt to make variable names based on the
filenames.

Thanks

Martin


From martin.hellwig at dcuktec.org  Wed Jul 29 19:05:04 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 00:05:04 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
Message-ID: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>

MalC0de wrote:
> hello there, I've a question :
> I want to know does python have any capability for using Ring0 and
> kernel functions for driver and device development stuff .
> if there's such a feature it is very good, and if there something for
> this kind that you know please refer me to some reference and show me
> some snippet .
> 
> thanks
> 
> - Malc0de

Python is interpreted, so the first requirement would be that the 
interpreter (the python VM to be more precise) would run in the kernel 
or that there is a way for the interpreter to delegate operations to 
kernel restricted operations. Most notably access to the memory location 
of the hardware you want to write a driver for and possibly also a way 
to pass through a callback function for triggered  interrupt coming from 
the hardware.

So technically speaking it shouldn't be impossible. And there is perhaps 
something to say for being able to write drivers in a readable/easy 
programming language however I am afraid that if such a beast would be 
made that it would remain an academical exercise only due to performance 
constraints.

Though I would love to play around with a system where the kernel is 
essentially only a python interpreter, with full raw access to the hardware.

But creating such a thing requires more talent and understanding than 
currently (and probably ever) in my possession.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From cjw at ncf.ca  Wed Jul 29 19:27:41 2009
From: cjw at ncf.ca (Colin J. Williams)
Date: Wed, 29 Jul 2009 19:27:41 -0400
Subject: Differences Between Arrays and Matrices in Numpy
In-Reply-To: <mailman.3919.1248899788.8015.python-list@python.org>
References: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>
	<mailman.3919.1248899788.8015.python-list@python.org>
Message-ID: <h4qltf$9i3$1@theodyn.ncf.ca>

Robert Kern wrote:
> On 2009-07-29 15:23, Nanime Puloski wrote:
>> What are some differences between arrays and matrices using the Numpy
>> library? When would I want to use arrays instead of matrices and vice
>> versa?
> 
> You will want to ask numpy questions on the numpy mailing list:
> 
>   http://www.scipy.org/Mailing_Lists
> 
> An overview of how the matrix subclass differs from ndarray, see the 
> documentation:
> 
>   
> http://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects 
> 
> 
> Basically, I suggest that you just use regular arrays always. There is a 
> syntactical convenience to matrix objects, but it does cause 
> incompatibilities with the majority of code that is written for regular 
> arrays. The convenience is usually not worth the cost.
> 

Numpy's arrays can have any dimensionality, whereas 
matrices[http://en.wikipedia.org/wiki/Matrix_%28mathematics%29], typically 
have two.  A single column can represent a vector or a single row can 
represent a transposed vector.

Does the additional cost arise because the commonly used procedures are 
accessed through numpy's array?

Colin W.



From rwanderley at rsw.digi.com.br  Wed Jul 29 19:30:21 2009
From: rwanderley at rsw.digi.com.br (Rodrigo S Wanderley)
Date: Wed, 29 Jul 2009 20:30:21 -0300
Subject: Does python have the capability for driver development ?
In-Reply-To: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com> (Martin P. Hellwig's
	message of "Thu, 30 Jul 2009 00:05:04 +0100")
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
Message-ID: <87skgf83ua.fsf@rsw.digi.com.br>

"Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:

> Python is interpreted, so the first requirement would be that the
> interpreter (the python VM to be more precise) would run in the kernel
> or that there is a way for the interpreter to delegate operations to
> kernel restricted operations. Most notably access to the memory
> location of the hardware you want to write a driver for and possibly
> also a way to pass through a callback function for triggered
> interrupt coming from the hardware.
>
> So technically speaking it shouldn't be impossible. And there is
> perhaps something to say for being able to write drivers in a
> readable/easy programming language however I am afraid that if such a
> beast would be made that it would remain an academical exercise only
> due to performance constraints.

What about user level device drivers? Think the Python VM could
communicate with the driver through the user space API.  Is there a
Python module for that?

-- 
Rodrigo S. Wanderley <rwanderley at rsw.digi.com.br>
  -- Blog: http://rsw.digi.com.br


From david.lyon at preisshare.net  Wed Jul 29 19:33:01 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Wed, 29 Jul 2009 19:33:01 -0400
Subject: Does python have the capability for driver development
	=?UTF-8?Q?=3F?=
In-Reply-To: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
Message-ID: <bbda6d96cb07cc681061ed765c96b13c@preisshare.net>

 MalC0de wrote:
> hello there, I've a question :
> I want to know does python have any capability for using Ring0 and
> kernel functions for driver and device development stuff .
> if there's such a feature it is very good, and if there something for
> this kind that you know please refer me to some reference and show me
> some snippet .

What operating system are you talking about?

Most device drivers run at ring 3 (or lower) and not zero. This way if
there
is a driver crash the whole operating system doesn't freeze.

Python is generally considered a high-level language. If you want
to play around with drivers.. usb serial.. etc do it at a python
level through the existing device drivers.

imho the performance of interpreted python isn't compatible with
writing block-mode device drivers (hard-disks) and so forth.

What hardware do you have that you need to write a device driver
for ? Isn't there a device driver available already? or do you
mean just a device controller?

David





From robert.kern at gmail.com  Wed Jul 29 19:42:05 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 29 Jul 2009 18:42:05 -0500
Subject: Differences Between Arrays and Matrices in Numpy
In-Reply-To: <h4qltf$9i3$1@theodyn.ncf.ca>
References: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>	<mailman.3919.1248899788.8015.python-list@python.org>
	<h4qltf$9i3$1@theodyn.ncf.ca>
Message-ID: <h4qmof$j58$1@ger.gmane.org>

On 2009-07-29 18:27, Colin J. Williams wrote:
> Robert Kern wrote:
>> On 2009-07-29 15:23, Nanime Puloski wrote:
>>> What are some differences between arrays and matrices using the Numpy
>>> library? When would I want to use arrays instead of matrices and vice
>>> versa?
>>
>> You will want to ask numpy questions on the numpy mailing list:
>>
>> http://www.scipy.org/Mailing_Lists
>>
>> An overview of how the matrix subclass differs from ndarray, see the
>> documentation:
>>
>> http://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects
>>
>>
>> Basically, I suggest that you just use regular arrays always. There is
>> a syntactical convenience to matrix objects, but it does cause
>> incompatibilities with the majority of code that is written for
>> regular arrays. The convenience is usually not worth the cost.
>
> Numpy's arrays can have any dimensionality, whereas
> matrices[http://en.wikipedia.org/wiki/Matrix_%28mathematics%29],
> typically have two. A single column can represent a vector or a single
> row can represent a transposed vector.
>
> Does the additional cost arise because the commonly used procedures are
> accessed through numpy's array?

Most functions are written to expect that its inputs behave like ndarrays; e.g. 
a*b is elementwise multiplication rather than matrix multiplication. When you 
use the matrix subclass, you are basically confining yourself to a smallish 
ghetto of functions that knows how to deal with matrix semantics. That's a huge 
cost compared to the relatively small syntactic cost of having to write dot(a,b) 
instead of (a*b).

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From ben+python at benfinney.id.au  Wed Jul 29 19:42:35 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 30 Jul 2009 09:42:35 +1000
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <87ljm72h04.fsf@benfinney.id.au>

dandi kain <dandi.kain at gmail.com> writes:

> What is the functionality of __ or _ , leading or trailing an object ,
> class ot function ?

There is no change in functionality. It has some slight effects on
import, but as a beginner you shouldn't need to worry about that.

> Is it just a naming convention to note special functions and objects ,
> or it really mean someting to Python ?

Both. It's a strongly-adhered-to naming convention, as an indicator to
the reader how that name should be used.

    foo      Ordinary name, part of public interface
    _foo     Ordinary name, part of internal-only interface
    __foo    Ordinary name, but will be mangled (this style used rarely)
    __foo__  Name which is used in a special way by Python

There's no change in the objects themselves; the underscores rather
indicate how those names are expected to be accessed.

-- 
 \         ?Pinky, are you pondering what I'm pondering?? ?I think so, |
  `\   Brain, but Tuesday Weld isn't a complete sentence.? ?_Pinky and |
_o__)                                                       The Brain_ |
Ben Finney



From martin.hellwig at dcuktec.org  Wed Jul 29 19:44:41 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 00:44:41 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <87skgf83ua.fsf@rsw.digi.com.br>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<87skgf83ua.fsf@rsw.digi.com.br>
Message-ID: <4A70DEE9.1060105@dcuktec.org>

Rodrigo S Wanderley wrote:
> <cut>
> What about user level device drivers? Think the Python VM could
> communicate with the driver through the user space API.  Is there a
> Python module for that?
>
>   
Sure why not?
Look for example to libusb, which provides a userspace environment and 
pyusb which uses that and provides an interface to Python.

-- 
MPH



From nyamatongwe+thunder at gmail.com  Wed Jul 29 19:55:34 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Wed, 29 Jul 2009 23:55:34 GMT
Subject: No PyPI search for 3.x compatible packages
Message-ID: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>

   There appears to be no way to search PyPI for packages that are
compatible with Python 3.x. There are classifiers for 'Programming
Language' including 'Programming Language :: Python :: 3' but that seems
to be for implementation language since there are so many packages that
specify C. There are a total of 109 packages classified with Python ::
[3, 3.0, 3.1] out of a total of 4829 packages.
http://pypi.python.org/pypi?:action=browse&show=all&c=214&c=533

   The search box appears to search for any word entered so a search
like "xml 3.0" or "xml AND 3.0" does not help.

   Some packages include version information in the Py Version column of
their download lists or embedded in the download file names. Projects
are often constrained to a particular set of Python versions so need to
choose packages that will work with those versions. It would be helpful
if PyPI made this information more visible and searchable.

   Neil


From malc0de.encrypt at gmail.com  Wed Jul 29 20:19:42 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Wed, 29 Jul 2009 17:19:42 -0700 (PDT)
Subject: Does python have the capability for driver development ?
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<87skgf83ua.fsf@rsw.digi.com.br> 
	<mailman.3929.1248911448.8015.python-list@python.org>
Message-ID: <94abbddc-dac7-4215-84d1-d4eb3f82724d@h21g2000yqa.googlegroups.com>

actually I mean driver programming under Windows operating system, if
you know, there's A kit name DDK available at microsoft's website for
developing device drivers under C / C++ environment, now i'm working
with this kind of toolkit, but when I started programming with Python,
I saw this is very good and easy to develop application in all aspects
of a programmer or customer .
I love python cuze I can write every application i want, it's easy and
it's very robust, But i thought if there's any available toolkit like
Microsoft DDK which can program driver under windows but based on
python it's very good and well, I don't know it's the lack of python
or interpreter concept but cuze of the extensibility of python if such
a good feature can be added to python it will be good enough.
actually I want to write device drivers in Ring0 mode or kernel
mode ...
please introduce me some resource for system programming, I know that
python is very well at system programming level.
thanks

- Malc0de


From wuwei23 at gmail.com  Wed Jul 29 20:24:03 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 29 Jul 2009 17:24:03 -0700 (PDT)
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <11942b01-07b4-44d9-9be5-92868493b706@g1g2000pra.googlegroups.com>

On Jul 30, 3:59?am, dandi kain <dandi.k... at gmail.com> wrote:
> What is the functionality of __ or _ , leading or trailing an object ,
> class ot function ? Is it just a naming convention to note special
> functions and objects , or it really mean someting to Python ?

I think everyone else has covered what you need to know, but there's
still one remaining pseudo-convention you might see in Python code,
and that's using _ as a label to indicate that you don't care about
the value it holds.

Overly simplistic example:

data_set = [('gold','junk'),('gold','junk'),...]

for keep, _ in data_set:
    ...

It's a convenient way of not having to come up with a label for
something you're not going to use, although arguably you get the same
effect with names like 'dummy', 'ignore' etc. Not everyone agrees with
this usage but you _will_ see it in use in other people's code, so it
helps to have a heads up.


From marcusw at cox.net  Wed Jul 29 20:24:16 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 20:24:16 -0400
Subject: Does python have the capability for driver development ?
In-Reply-To: <mailman.3929.1248911448.8015.python-list@python.org>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<87skgf83ua.fsf@rsw.digi.com.br>
	<mailman.3929.1248911448.8015.python-list@python.org>
Message-ID: <h4qp7u$15od$1@adenine.netfront.net>

On 7/29/2009 7:44 PM, Martin P. Hellwig wrote:
> Rodrigo S Wanderley wrote:
>> <cut>
>> What about user level device drivers? Think the Python VM could
>> communicate with the driver through the user space API.  Is there a
>> Python module for that?
>>
>>   
> Sure why not?
> Look for example to libusb, which provides a userspace environment and 
> pyusb which uses that and provides an interface to Python.
> 
iicr pyusb uses a c interface to libusb, not python...

Marcus


From http  Wed Jul 29 21:04:47 2009
From: http (Paul Rubin)
Date: 29 Jul 2009 18:04:47 -0700
Subject: How to "gunzip-iterate" over a file?
References: <h4qa2g$i5v$1@reader1.panix.com>
	<mailman.3916.1248898979.8015.python-list@python.org>
Message-ID: <7x8wi7j80g.fsf@ruckus.brouhaha.com>

Robert Kern <robert.kern at gmail.com> writes:
> f = gzip.open('filename.gz')
> for line in f:
>      print line

or use f.read(nbytes) to read n uncompressed bytes from f.  Note that
the standard iterator (which iterates over lines) can potentially
consume an unbounded amount of memory if the file contains no newlines.


From greg at cosc.canterbury.ac.nz  Wed Jul 29 21:09:14 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Thu, 30 Jul 2009 13:09:14 +1200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <mailman.3879.1248854780.8015.python-list@python.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<200907281035.48713.hendrik@microcorp.co.za>	<4A6F1506.9030207@mrabarnett.plus.com>
	<mailman.3879.1248854780.8015.python-list@python.org>
Message-ID: <7dca4iF2bgbn5U1@mid.individual.net>

Hendrik van Rooyen wrote:

> And if code is data, where is Pythons ALTER statement?

class Duck:

   def quack(self):
     print "Quack!"

def moo():
   print "Moo!"

def ALTER(obj, name, TO_PROCEED_TO):
   setattr(obj, name, TO_PROCEED_TO)

d = Duck()
ALTER(d, 'quack', TO_PROCEED_TO = moo)
d.quack()

-- 
Greg


From clp2 at rebertia.com  Wed Jul 29 21:21:32 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 18:21:32 -0700
Subject: Working with platform.system()
In-Reply-To: <9a5b5be90907290610t1868ef07p20a5c2bdc3404ab8@mail.gmail.com>
References: <9a5b5be90907290610t1868ef07p20a5c2bdc3404ab8@mail.gmail.com>
Message-ID: <50697b2c0907291821l54f30d99q44df2a9188a917f0@mail.gmail.com>

On Wed, Jul 29, 2009 at 6:10 AM, v1d4l0k4<v1d4l0k4 at gmail.com> wrote:
> Hi!
>
> I want to know how I can get different expected return values by
> platform.system() method. I want to sniff some systems (Linux, Windows, Mac,
> BSD, Solaris) and I don't know how I can check them correctly. Could you
> give me some expected return values that you know?

On my Mac, I get "Darwin".

You should file a bug in the docs after compiling the results, to help
future users.

Cheers,
Chris
-- 
http://blog.rebertia.com


From draghuram at gmail.com  Wed Jul 29 23:00:57 2009
From: draghuram at gmail.com (Raghuram Devarakonda)
Date: Wed, 29 Jul 2009 20:00:57 -0700 (PDT)
Subject: Connecting multiple test cases in a sort of pipe
Message-ID: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>


Hi,

I have three functions - create(), list(), and delete(). create()
creates a new name in the file system hierarchy while list() displays
all such created names and delete() removes them. I would like to
write test cases for each of these functions, say, test_create() ,
test_list(), and test_delete() using the unittest module. It easily
follows that test_list() and test_delete() will need to know the exact
name that was created in test_create() in order to properly validate
list() and delete(). One option is for test_create() to always use a
hard coded name but unfortunately this is not feasible.

Another way would be for test_create() to pass the new name down to
the next test case test_list() which would do the same and pass the
name down to test_delete(). In other words, the requirement is to
connect all three test cases in a kind of pipe. This facility is
obviously not currently present in the unittest module and nor does it
seem to be available in other frameworks (such as py.test and nose, I
only skimmed the feature list).

I am thinking of implementing this feature on top of unittest.TestCase
and would like to know what others think of the idea. Is there a
framework that has similar feature? Or perhaps, given my requirement
as stated above, is there some alternate way of implementing it? I
greatly appreciate any feed back.

Thanks,
Raghu




From rt8396 at gmail.com  Wed Jul 29 23:06:33 2009
From: rt8396 at gmail.com (r)
Date: Wed, 29 Jul 2009 20:06:33 -0700 (PDT)
Subject: Confessions of a Python fanboy
Message-ID: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>


Hello fellow Pythonista's it's nice to be back after such a long
hiatus. I have recently realized my  blind love affair with Python was
just that. I must admit there are better ways to program. Like your
first lay, your first programing language can leave an indelible mark
on you, but like all young chaps, the passion for programming has
sweep me away into vast new orgies of programming bliss. (ig ,little
head guides the big one.)

My adventures in Ruby.
an autobyography by rt8396

After breaking free from the wild love affair i had with Python, a new
day had dawned. I dried my eyes and soon discovered the Ruby language
(not by choice however) --now don't worry fellow Pythonistas, i am
still on your side (mostly)  -- but i now realize Ruby has some good
things going for it. For instance...

1.) No need to use "()" to call a function with no arguments.
Python --> "obj.m2().m3()" --ugly
  Ruby --> "obj.m1.m2.m3"  -- sweeet!
Man, i must admit i really like this, and your code will look so much
cleaner.

2.) the .each method
container.each{|localVar| block}
This method can really cleanup some ugly for loops, although i really
like the readability of for loops.

3.) true OOP
Now before you go and get all "huffy" over this statement, hear me
out. Python is the best language in the world. But it damn sure has
some warts! "len(this)" instead of "obj.length" max(that) instead of
[1,2,3,4,5].max(). You know what i am talking about here people. We
all get complacent and It seems easier to just cope with these
problems instead of fighting for change. But look at the French,  WHAT
THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!

As for the rest of Ruby, i am not impressed. The redundant usage of
"end" over indention perplexes me. The Perlish feel of "require" and
the horrifically cryptic idioms of Ruby regular expressions. The
"puts" and "gets" seem childish and the math class does not even have
a degrees or radians function!

Anyway, i thought i would get this off my chest and catch up with old
friends in the meantime. We can all make Python the perfect language
it needs to be, but it ain't gonna be easy!
Thank you all

PS stay tuned for more from this series....




From rt8396 at gmail.com  Wed Jul 29 23:43:58 2009
From: rt8396 at gmail.com (r)
Date: Wed, 29 Jul 2009 20:43:58 -0700 (PDT)
Subject: IDLE Config Problems
References: <mailman.3922.1248902818.8015.python-list@python.org>
Message-ID: <37c1f7fa-8008-41b0-b2c4-d9c1e5288e2e@v20g2000yqm.googlegroups.com>

On Jul 29, 3:55?pm, "Russ Davis" <Russ.Da... at njpines.state.nj.us>
wrote:
> I am just getting started with Python and have installed v. 2.5.4 ?Idle version 1.2.4 ?I can't seem to get the idle to display text. ?It seems as if the install went fine. ?I start up the idle and the screen is blank. ?No text. ?It seems as if I can type on the screen but I just can't see the characters. ? I go to the config menu and it bombs and brings up the Visual Studio debugger. ?The computer that I am trying to install it on is a windows xp laptop serv pack 2. ? I have a workstation here that I am using also with the same os and the idle works fine. ?Any hints as to what might be interfering with the idle config.
>

just spit balling here, but have you tried a un-install, re-install

""" Bad things can happen to good installers """


From darkneter at gmail.com  Wed Jul 29 23:52:06 2009
From: darkneter at gmail.com (NighterNet)
Date: Wed, 29 Jul 2009 20:52:06 -0700 (PDT)
Subject: socket send
Message-ID: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>

I am trying to figure out how to send text or byte in python 3.1. I am
trying to send data to flash socket to get there. I am not sure how to
work it.

buff= 'id=' , self.id , ':balive=False\n'
clientSock.send(buff);


From wuwei23 at gmail.com  Thu Jul 30 00:04:27 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 29 Jul 2009 21:04:27 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>

On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.

How do you distinguish between calling a method with no arguments, and
getting access to the method object itself (because it _is_ an object,
y'know, it's OO all the way down...)?

> 2.) the .each method
> container.each{|localVar| block}
> This method can really cleanup some ugly for loops, although i really
> like the readability of for loops.

map(lambda localVar: <block>, sequence)

or:

def usefully_named_func(var):
    <block>
    return var

transformed = [usefully_named_func(v) for v in sequence]

> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max().

As the Zen says: '[P]racticality beats purity'. Personally, I'm not
sure how a handful of convenient built-in functions make a language in
which _everything is an object_ somehow "false" OO.

If you're really that concerned with writing "true" OO (for some
wildly variable value of "true"), there's nothing stopping you from
doing so now:

    obj.__len__()

With max(), this is a built-in that takes _any_ iterable and an
optional key function, and returns the highest value as per the key.
This means that _every_ iterable object - as _well_ as every object
that supports enough of the iterator protocol - can be handed to max()
and a result obtained. So at best, I just need to make sure my new
sequence-type provides the iterator protocol and viola, it works with
max() without me having to hand-code a .max() that's specialised for
my new type, and without Python forcing me to have a complex
inheritance chain just to make sure I include the right
MaxableSequence ancestor to inherit the right .max().

> PS stay tuned for more from this series....

Is this going to be more of you telling us - without any apparent
irony whatsoever - how Ruby has some valid points after all your
vilification last year when we said the same to you?  If so, where can
I sign up?!

(You should consider trading guest spot posts with Xah Lee on your
respective blogs. You both have a very similar approach to programming
& programming languages and I think the synergy would be amazing to
see.)


From pdlemper at earthlink.net  Thu Jul 30 00:24:11 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Wed, 29 Jul 2009 23:24:11 -0500
Subject: gamma approximation : what is module cmath and where is it located ?
Message-ID: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>

The following numerical approximation for Euler's Gamma function
is found in http://en.wikipedia.org/wiki/Lanczos_approximation

from cmath import *
 
# Coefficients used by the GNU Scientific Library
g = 7
p = [0.99999999999980993, 676.5203681218851, -1259.1392167224028,
     771.32342877765313, -176.61502916214059, 12.507343278686905,
     -0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7]
 
def gamma(z):
    z = complex(z)
    # Reflection formula
    if z.real < 0.5:
        return pi / (sin(pi*z)*gamma(1-z))
    else:
        z -= 1
        x = p[0]
        for i in range(1, g+2):
            x += p[i]/(z+i)
        t = z + g + 0.5
        return sqrt(2*pi) * t**(z+0.5) * exp(-t) * x


This works in Python 3.0    
  
But I can't figure out where it gets "cmath".    Searching the Python 
directory reveals no more than a test_cmath.  The only cmath I can find
is a header file in another directory  turboc++\Borland\include\

dir(cmath) reveals 23 functions overlapping the 37 functions of
the math module.

What is cmath, where did it come from and how does it differ from
the standard math module  ?

Dave WB3DWE
                                   I saw the number 4 in silver,  Guido
                                     (apologies to Wm Carlos Williams)


From clp2 at rebertia.com  Thu Jul 30 00:27:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 21:27:20 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <50697b2c0907292127l98ff61aief7f7205b5b5ca9@mail.gmail.com>

On Wed, Jul 29, 2009 at 9:04 PM, alex23<wuwei23 at gmail.com> wrote:
> On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
>> 1.) No need to use "()" to call a function with no arguments.
>> Python --> "obj.m2().m3()" --ugly
>> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
>> Man, i must admit i really like this, and your code will look so much
>> cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?

IIRC from the Pickaxe, to get at a method object, you call a method on
the object whose specific job it is to return method objects.
Unsurprisingly, this method is itself named "method". So:

foo.bar #calls the "bar" method on foo
foo.method(:bar) #returns the method "bar" of foo, as an object

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Thu Jul 30 00:34:07 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 21:34:07 -0700
Subject: gamma approximation : what is module cmath and where is it 
	located ?
In-Reply-To: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <50697b2c0907292134p594105fag2bf99e0b5e14e35c@mail.gmail.com>

On Wed, Jul 29, 2009 at 9:24 PM, <pdlemper at earthlink.net> wrote:
<snip>
> But I can't figure out where it gets "cmath". ? ?Searching the Python
> directory reveals no more than a test_cmath. ?The only cmath I can find
> is a header file in another directory ?turboc++\Borland\include\
>
> dir(cmath) reveals 23 functions overlapping the 37 functions of
> the math module.
>
> What is cmath, where did it come from and how does it differ from
> the standard math module ??

It's a module in the standard library:
http://docs.python.org/library/cmath.html

The difference is that it handles complex numbers, whereas the plain
"math" module doesn't.
I would guess the reason there are separate modules is for
performance, so as to avoid having to dispatch on type at runtime. But
this is only a guess.

Cheers,
Chris
-- 
http://blog.rebertia.com


From pavlovevidence at gmail.com  Thu Jul 30 00:36:31 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 29 Jul 2009 21:36:31 -0700 (PDT)
Subject: gamma approximation : what is module cmath and where is it 
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>

On Jul 29, 9:24?pm, pdlem... at earthlink.net wrote:
> What is cmath, where did it come from and how does it differ from
> the standard math module ??

What happened when you did a keyword search for "cmath" in the Python
library documentation?

What happened when you entered "python cmath" in Google?


Carl Banks


From pavlovevidence at gmail.com  Thu Jul 30 00:43:47 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 29 Jul 2009 21:43:47 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <ab5cb173-7069-4bab-b693-70cfd145c3f4@h11g2000yqb.googlegroups.com>

On Jul 29, 9:04?pm, alex23 <wuwe... at gmail.com> wrote:
> On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
>
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?
>
> > 2.) the .each method
> > container.each{|localVar| block}
> > This method can really cleanup some ugly for loops, although i really
> > like the readability of for loops.
>
> map(lambda localVar: <block>, sequence)
>
> or:
>
> def usefully_named_func(var):
> ? ? <block>
> ? ? return var
>
> transformed = [usefully_named_func(v) for v in sequence]
>
> > 3.) true OOP
> > Now before you go and get all "huffy" over this statement, hear me
> > out. Python is the best language in the world. But it damn sure has
> > some warts! "len(this)" instead of "obj.length" max(that) instead of
> > [1,2,3,4,5].max().
>
> As the Zen says: '[P]racticality beats purity'. Personally, I'm not
> sure how a handful of convenient built-in functions make a language in
> which _everything is an object_ somehow "false" OO.
>
> If you're really that concerned with writing "true" OO (for some
> wildly variable value of "true"), there's nothing stopping you from
> doing so now:
>
> ? ? obj.__len__()
>
> With max(), this is a built-in that takes _any_ iterable and an
> optional key function, and returns the highest value as per the key.
> This means that _every_ iterable object - as _well_ as every object
> that supports enough of the iterator protocol - can be handed to max()
> and a result obtained. So at best, I just need to make sure my new
> sequence-type provides the iterator protocol and viola, it works with
> max() without me having to hand-code a .max() that's specialised for
> my new type, and without Python forcing me to have a complex
> inheritance chain just to make sure I include the right
> MaxableSequence ancestor to inherit the right .max().
>
> > PS stay tuned for more from this series....
>
> Is this going to be more of you telling us - without any apparent
> irony whatsoever - how Ruby has some valid points after all your
> vilification last year when we said the same to you? ?If so, where can
> I sign up?!
>
> (You should consider trading guest spot posts with Xah Lee on your
> respective blogs. You both have a very similar approach to programming
> & programming languages and I think the synergy would be amazing to
> see.)

Here is some wisdom from Guido van Rossum on the matter:

http://mail.python.org/pipermail/python-dev/2006-May/064841.html


Carl Banks


From pdlemper at earthlink.net  Thu Jul 30 01:25:11 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Thu, 30 Jul 2009 00:25:11 -0500
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
Message-ID: <72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>

On Wed, 29 Jul 2009 21:36:31 -0700 (PDT), Carl Banks
<pavlovevidence at gmail.com> wrote:

>On Jul 29, 9:24?pm, pdlem... at earthlink.net wrote:
>> What is cmath, where did it come from and how does it differ from
>> the standard math module ??
>
>What happened when you did a keyword search for "cmath" in the Python
>library documentation?
>
>What happened when you entered "python cmath" in Google?
>
>
>Carl Banks

Thanks Carl & Chris.  I've read the Python doc 10.3 and now understand
its for complex arithmetic. 
I've used python a few months and expected to find cmath seperately
sort of as a " header file".  A text search failed.  I now understand
its in the Python Standard Library, which I assume is that big file
Python30\LIBS\libpython30.a        And this is not readable as text.
Dave


From wuwei23 at gmail.com  Thu Jul 30 01:28:06 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 29 Jul 2009 22:28:06 -0700 (PDT)
Subject: IDLE Config Problems
References: <mailman.3922.1248902818.8015.python-list@python.org>
Message-ID: <89553ecc-a30e-4280-8a42-17a18af50ba9@v37g2000prg.googlegroups.com>

On Jul 30, 6:55?am, "Russ Davis" <Russ.Da... at njpines.state.nj.us>
wrote:
> I am just getting started with Python and have installed v. 2.5.4 ?
> Idle version 1.2.4 ?I can't seem to get the idle to display text. ?It
> seems as if the install went fine. ?I start up the idle and the screen
> is blank. ?No text. ?It seems as if I can type on the screen but I just
> can't see the characters.

Is this the official python.org distribution you're trying? I can't
speak from experience, but I'm wondering if it doesn't include the
pyreadline module by default, which you'll require under Windows
(although I would've expected to hear more problems like your's if
this is the case). You can easily check this by going to C:
\Python25\Lib\site-packages and looking for a folder or a file called
pyreadline. If it's not, you'll have to install it separately.

If you're not already familiar with it, I do recommend checking out
the ActiveState ActivePython distribution instead, especially if
you're working under Windows. It includes a lot of Windows-specific
3rd party modules, such as the win32all modules, and it definitely
includes pyreadline.

Is there any particular reason why you're opting for Python 2.5.x? 2.6
should be pretty compatible with most things in the 2.x stream and
it's a handy stepping stone towards using 3.x (which, admittedly, is
probably the last of your concerns when you're first setting up...)


From tjreedy at udel.edu  Thu Jul 30 01:35:19 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 01:35:19 -0400
Subject: gamma approximation : what is module cmath and where is it located
	?
In-Reply-To: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <h4rben$qc1$1@ger.gmane.org>

pdlemper at earthlink.net wrote:
> The following numerical approximation for Euler's Gamma function
> is found in http://en.wikipedia.org/wiki/Lanczos_approximation
> 
> from cmath import *

> But I can't figure out where it gets "cmath".

The Python documentation set has a module index. Really handy. I use it 
all the time. cmath is under 'c'.

To answer some of your question:

 >>> math.sqrt(-1)
Traceback (most recent call last):
   File "<pyshell#3>", line 1, in <module>
     math.sqrt(-1)
ValueError: math domain error
 >>> cmath.sqrt(-1)
1j

Which to use depends on the behavior you want.

tjr



From Ron.Barak at lsi.com  Thu Jul 30 02:01:28 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 07:01:28 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <4A708F68.1010505@ieee.org>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>


> -----Original Message-----
> From: Dave Angel [mailto:davea at ieee.org] 
> Sent: Wednesday, July 29, 2009 21:05
> To: Barak, Ron
> Cc: 'python-list at python.org'
> Subject: Re: Run pyc file without specifying python path ?
> 
> Barak, Ron wrote:
> > Hi,
> >
> > I wanted to make a python byte-code file executable, 
> expecting to be able to run it without specifying "python" on 
> the (Linux bash) command line.
> >
> > So, I wrote the following:
> >
> > [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
> >
> > print "hello"
> > [root at VMLinux1 python]#
> >
> > and made its pyc file executable:
> >
> > [root at VMLinux1 python]# ls -ls test_pyc.pyc
> > 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> > [root at VMLinux1 python]#
> >
> > So, I see:
> >
> > [root at VMLinux1 python]# file test_pyc.py*
> > test_pyc.py:  a python script text executable
> > test_pyc.pyc: python 2.3 byte-compiled
> > [root at VMLinux1 python]#
> >
> > If I try to do the following, no problem:
> >
> > [root at VMLinux1 python]# python test_pyc.pyc hello
> > [root at VMLinux1 python]#
> >
> > However, the following fails:
> >
> > [root at VMLinux1 python]# ./test_pyc.pyc
> > -bash: ./test_pyc.pyc: cannot execute binary file
> > [root at VMLinux1 python]#
> >
> > Is there a way to run a pyc file without specifying the 
> python path ?
> >
> > Bye,
> > Ron.
> >
> >   
> I don't currently run Unix, but I think I know the problem.
> 
> In a text file, the shell examines the first line, and if it 
> begins #! 
> it's assumed to point to the executable of an interpreter for 
> that text file.  Presumably the same trick doesn't work for a 
> .pyc file.
> 
> Why not write a trivial wrapper.py file, don't compile it, 
> and let that invoke the main code in the .pyc file?
> 
> Then make wrapper.py executable, and you're ready to go.
> 
> DaveA
> 
> 

Hi Dave,
Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.
Bye,
Ron. 

From deets at nospam.web.de  Thu Jul 30 02:33:54 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 08:33:54 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <slrnh71g6g.djc.nick@irishsea.home.craig-wood.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<7dbs8nF2br07nU1@mid.uni-berlin.de>
	<slrnh71g6g.djc.nick@irishsea.home.craig-wood.com>
Message-ID: <7dct6iF2bhhshU1@mid.uni-berlin.de>

Nick Craig-Wood schrieb:
> Diez B. Roggisch <deets at nospam.web.de> wrote:
>>  MalC0de schrieb:
>>> hello there, I've a question :
>>> I want to know does python have any capability for using Ring0 and
>>> kernel functions for driver and device development stuff .
>>> if there's such a feature it is very good, and if there something for
>>> this kind that you know please refer me to some reference and show me
>>> some snippet .
>>  No, it can't do such things. At least it isn't embedded in the kernel - 
>>  in theory that might be possible, but given the timing-constraints and 
>>  concurrency-requirements, it's not really feasible.
> 
> You can write FUSE (file systems in userspace) drivers in python I believe.
> Not the same as running in ring0 but in most senses a kernel driver...

No. That's why it is called "userspace". The kernel just hooks into a 
running program.

Diez



From __peter__ at web.de  Thu Jul 30 02:41:00 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 30 Jul 2009 08:41 +0200
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
	<72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>
Message-ID: <h4rf9f$jmq$01$1@news.t-online.com>

pdlemper at earthlink.net wrote:

> I've used python a few months and expected to find cmath seperately
> sort of as a " header file".  A text search failed.  I now understand
> its in the Python Standard Library, which I assume is that big file
> Python30\LIBS\libpython30.a        

Python 3.1 is no longer maintained. I recommend that you upgrade to Python 3.1.

> And this is not readable as text.

The module is written in C. The source code for the 3.1 version is here:

http://svn.python.org/view/python/branches/release31-maint/Modules/cmathmodule.c?view=markup

If you want the source for all parts of python written in C you can download the sourcecode at

http://www.python.org/download/releases/3.1/

Peter




From deets at nospam.web.de  Thu Jul 30 02:43:27 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 08:43:27 +0200
Subject: Connecting multiple test cases in a sort of pipe
In-Reply-To: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>
References: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>
Message-ID: <7dctogF29q4c6U1@mid.uni-berlin.de>

Raghuram Devarakonda schrieb:
> Hi,
> 
> I have three functions - create(), list(), and delete(). create()
> creates a new name in the file system hierarchy while list() displays
> all such created names and delete() removes them. I would like to
> write test cases for each of these functions, say, test_create() ,
> test_list(), and test_delete() using the unittest module. It easily
> follows that test_list() and test_delete() will need to know the exact
> name that was created in test_create() in order to properly validate
> list() and delete(). One option is for test_create() to always use a
> hard coded name but unfortunately this is not feasible.
> 
> Another way would be for test_create() to pass the new name down to
> the next test case test_list() which would do the same and pass the
> name down to test_delete(). In other words, the requirement is to
> connect all three test cases in a kind of pipe. This facility is
> obviously not currently present in the unittest module and nor does it
> seem to be available in other frameworks (such as py.test and nose, I
> only skimmed the feature list).
> 
> I am thinking of implementing this feature on top of unittest.TestCase
> and would like to know what others think of the idea. Is there a
> framework that has similar feature? Or perhaps, given my requirement
> as stated above, is there some alternate way of implementing it? I
> greatly appreciate any feed back.

Write a TestCase-subclass that simply works like this:


class FileTests(TestCase):


    def test_create(self):
        self.created_file = create()
        assert something


    def test_list(self):
        self.test_create()
        delete(self.created_file)


Passing state around is one of the reasons objects have been invented :) 
And nobody ever said that you can't invoke a test-method from somewhere 
else.

Diez


From clp2 at rebertia.com  Thu Jul 30 02:53:36 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 23:53:36 -0700
Subject: gamma approximation : what is module cmath and where is it 
	located ?
In-Reply-To: <h4rf9f$jmq$01$1@news.t-online.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
	<72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>
	<h4rf9f$jmq$01$1@news.t-online.com>
Message-ID: <50697b2c0907292353i479f5d70ke59a91c330b6d8f7@mail.gmail.com>

On Wed, Jul 29, 2009 at 11:41 PM, Peter Otten<__peter__ at web.de> wrote:
> pdlemper at earthlink.net wrote:
>
>> I've used python a few months and expected to find cmath seperately
>> sort of as a " header file". ?A text search failed. ?I now understand
>> its in the Python Standard Library, which I assume is that big file
>> Python30\LIBS\libpython30.a
>
> Python 3.1 is no longer maintained. I recommend that you upgrade to Python 3.1.

(He meant to say 3.0.x is no longer maintained.)

- Chris
-- 
http://blog.rebertia.com


From __peter__ at web.de  Thu Jul 30 03:06:31 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 30 Jul 2009 09:06:31 +0200
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
	<72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>
	<h4rf9f$jmq$01$1@news.t-online.com>
	<mailman.3936.1248936819.8015.python-list@python.org>
Message-ID: <h4rgp9$6vv$00$1@news.t-online.com>

Chris Rebert wrote:

> On Wed, Jul 29, 2009 at 11:41 PM, Peter Otten<__peter__ at web.de> wrote:
>> pdlemper at earthlink.net wrote:
>>
>>> I've used python a few months and expected to find cmath seperately
>>> sort of as a " header file".  A text search failed.  I now understand
>>> its in the Python Standard Library, which I assume is that big file
>>> Python30\LIBS\libpython30.a
>>
>> Python 3.1 is no longer maintained. I recommend that you upgrade to
>> Python 3.1.
> 
> (He meant to say 3.0.x is no longer maintained.)

Ouch. Thanks for the correction.



From xubin.cz at gmail.com  Thu Jul 30 03:12:33 2009
From: xubin.cz at gmail.com (xubin.cz)
Date: Thu, 30 Jul 2009 00:12:33 -0700 (PDT)
Subject: beautiful soup
Message-ID: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>

hi, everyone

Is there any pakage or module handling html document like beautiful
soup?

thanks a lot


From deets at nospam.web.de  Thu Jul 30 03:30:48 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 09:30:48 +0200
Subject: beautiful soup
In-Reply-To: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
References: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
Message-ID: <7dd0h8F2a2he0U1@mid.uni-berlin.de>

xubin.cz schrieb:
> hi, everyone
> 
> Is there any pakage or module handling html document like beautiful
> soup?

why don't you *use* beautiful soup? It is a module...

Diez


From enleverLesX_XXmcX at XmclavXeauX.com  Thu Jul 30 03:54:21 2009
From: enleverLesX_XXmcX at XmclavXeauX.com (Michel Claveau - MVP)
Date: Thu, 30 Jul 2009 09:54:21 +0200
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
Message-ID: <4a7151b2$0$17782$ba4acef3@news.orange.fr>

Hi!

> Python is interpreted

No. Python is compiled (--> .pyc)
But the term "to compile" is not always unambiguous...
And the notion of "compiler" is not attached to Python (the language), but is attached to the implementation.

@+

MCI


From massi_srb at msn.com  Thu Jul 30 03:54:31 2009
From: massi_srb at msn.com (Massi)
Date: Thu, 30 Jul 2009 00:54:31 -0700 (PDT)
Subject: Bug in IEHtmlWindow?
Message-ID: <8a5ed753-d437-45a6-8fee-300eea1207ca@c2g2000yqi.googlegroups.com>

Hi everyone, I'm trying to use IEHtmlWindow in my application (python
2.5, wxpython 2.8 on win xp). Everything is ok, but I encountered a
problem which also affects the demo. If I make a research on google a
strange message appears, saying (I'll try to translate from italian):

Error during execution.
Do you want to run the debug?

line 29:
error: 'r' is NULL or it is not an object

Did anybody have the same problem? is it a bug?
Thanks in advance for your help.


From masklinn at masklinn.net  Thu Jul 30 03:55:24 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 09:55:24 +0200
Subject: beautiful soup
In-Reply-To: <7dd0h8F2a2he0U1@mid.uni-berlin.de>
References: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
	<7dd0h8F2a2he0U1@mid.uni-berlin.de>
Message-ID: <A62D275B-D411-4DDD-B315-03073102082D@masklinn.net>

On 30 Jul 2009, at 09:30 , Diez B. Roggisch wrote:
> xubin.cz schrieb:
>> hi, everyone
>> Is there any pakage or module handling html document like beautiful
>> soup?
>
> why don't you *use* beautiful soup? It is a module...
Or lxml, which works a bit better than BF 3.1 (post parser change)  
nowadays.


From martin.hellwig at dcuktec.org  Thu Jul 30 04:03:26 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 09:03:26 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <h4qp7u$15od$1@adenine.netfront.net>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<87skgf83ua.fsf@rsw.digi.com.br>
	<mailman.3929.1248911448.8015.python-list@python.org>
	<h4qp7u$15od$1@adenine.netfront.net>
Message-ID: <sOydnT-s_a9SzuzXnZ2dnUVZ8imdnZ2d@bt.com>

Marcus Wanner wrote:
<cut>
>> Look for example to libusb, which provides a userspace environment and 
>> pyusb which uses that and provides an interface to Python.
>>
> iicr pyusb uses a c interface to libusb, not python...
> 

According to them they use ctypes indeed. Sorry if I was misleading in 
my explanation.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From martin.hellwig at dcuktec.org  Thu Jul 30 04:05:48 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 09:05:48 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <4a7151b2$0$17782$ba4acef3@news.orange.fr>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
Message-ID: <sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>

Michel Claveau - MVP wrote:
> Hi!
> 
>> Python is interpreted
> 
> No. Python is compiled (--> .pyc)
> But the term "to compile" is not always unambiguous...
> And the notion of "compiler" is not attached to Python (the language), but is attached to the implementation.
> 
> @+
> 
> MCI

Well the pyc, which I thought was the Python bytecode, is then 
interpreted by the VM.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From javier.collado at gmail.com  Thu Jul 30 04:17:24 2009
From: javier.collado at gmail.com (Javier Collado)
Date: Thu, 30 Jul 2009 10:17:24 +0200
Subject: string.Template issue
Message-ID: <c83cde5a0907300117l7ca2f415jbd1c714918bf2d28@mail.gmail.com>

Hello,

In the string.Template documentation
(http://docs.python.org/library/string.html) it's explained that if a
custom regular expression for pattern substitution is needed, it's
possible to override idpattern class attribute (whose default value is
[_a-z][_a-z0-9]*).

However, if the custom pattern that is needed is just uppercase
letters something like [A-Z]+ won't work because of the following line
in the _TemplateMetaclass class __init__ method:
cls.pattern = _re.compile(pattern, _re.IGNORECASE | _re.VERBOSE)

I would say that this is an error (IGNORECASE just shouldn't be there)
and that the line above should be:
cls.pattern = _re.compile(pattern, _re.VERBOSE)
and the default value for idpattern:
[_a-zA-Z][_a-zA-Z0-9]*

Do you agree on this? Is there any reason for the IGNORECASE option to
be passed to re.compile?

Best regards,
    Javier


From kunguz at gmail.com  Thu Jul 30 05:02:04 2009
From: kunguz at gmail.com (=?ISO-8859-9?Q?Kaan_AK=DE=DDT?=)
Date: Thu, 30 Jul 2009 11:02:04 +0200
Subject: Pyplot
Message-ID: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>

I am a newbee in Python. I have some problem with usage of Pyplot. I have a
loop that creates plot in every end of it. Problem starts here: The first
plot is fine but the second one is plotted onto the first plot. I use:

plt.cla()
plt.draw()
plt.hold(False)
plt.close()
plt.clf()

but nothing works. Perhaps I am having a problem with basics, please help me
if you know something about it.

Kaan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/bfea180c/attachment.html>

From lists at cheimes.de  Thu Jul 30 05:10:32 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 30 Jul 2009 11:10:32 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
Message-ID: <h4ro29$rgo$1@ger.gmane.org>

Martin P. Hellwig wrote:
> Well the pyc, which I thought was the Python bytecode, is then
> interpreted by the VM.

Python is often referred as byte-code interpreted language. Most modern
languages are interpreted languages. The list [1] is rather long.
Technically speaking even native code is interpreted by the micro code
of most CPUs.

[1] http://en.wikipedia.org/wiki/Interpreted_language
[2] http://en.wikipedia.org/wiki/Microcode



From ben+python at benfinney.id.au  Thu Jul 30 05:14:54 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 30 Jul 2009 19:14:54 +1000
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
Message-ID: <878wi6v8fl.fsf@benfinney.id.au>

"Michel Claveau - MVP"<enleverLesX_XXmcX at XmclavXeauX.com> writes:

> Hi!
> 
> > Python is interpreted
> 
> No.

Yes. The same Python code is both interpreted and compiled so as to run
it.

> Python is compiled (--> .pyc)

The Python bytecode (the contents of the compiled ?foo.pyc? file) is
then interpreted by the run-time Python interpreter, to actually run the
program.

-- 
 \           ?Value your freedom or you will lose it, teaches history. |
  `\     ?Don't bother us with politics,? respond those who don't want |
_o__)                               to learn.? ?Richard Stallman, 2002 |
Ben Finney



From python at rgbaz.eu  Thu Jul 30 05:17:51 2009
From: python at rgbaz.eu (PythonAB)
Date: Thu, 30 Jul 2009 11:17:51 +0200
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
Message-ID: <157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>

>>
> Hi Dave,
> Your solution sort of defeats my intended purpose (sorry for not  
> divulging my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python  
> script, and look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want  
> a cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?)  
> version of the application, because it'll grow the resulting file  
> significantly, and I don't have the experience to know how it will  
> run on different Linuxes.
> Bye,
> Ron.

Hey Ron,

What i usually do to accomplish this is compile the script to a .pyc  
just like you
did and then call that pyc from another script that's not compiled.
so in your case the not compiled script looks like:

#!/usr/bin/env python

import test_pyc.pyc



then run that script...

hope this helps...



alternatively you might have a look at:
http://www.pyinstaller.org/



gr
Arno
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/f303bad5/attachment.html>

From lists at cheimes.de  Thu Jul 30 05:27:51 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 30 Jul 2009 11:27:51 +0200
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
Message-ID: <h4rp2n$u0o$1@ger.gmane.org>

Barak, Ron wrote:
> Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.

Ask Google for binfmt-support. Hint: Each Python version has its own
magic header.

Christian



From kunguz at gmail.com  Thu Jul 30 05:29:28 2009
From: kunguz at gmail.com (=?ISO-8859-9?Q?Kaan_AK=DE=DDT?=)
Date: Thu, 30 Jul 2009 11:29:28 +0200
Subject: Pyplot
In-Reply-To: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
References: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
Message-ID: <8fa7fe790907300229i496f7886w3c92676e51e0d9fa@mail.gmail.com>

Please help me I have been dealing with this little piece of code for 2
days. I am stuck and loosing time with it.

plt.figure(count)
            plt.xlabel("Time steps")
            plt.ylabel("Values")
            plt.title("Output of ADCs")
            plt.plot(timing,adc0)
            plt.plot(timing,adc1)
            plt.plot(timing,adc3)
            plt.show()
            plt.clf()
            plt.cla()
            plt.close()

30 Temmuz 2009 11:02 tarihinde Kaan AK??T <kunguz at gmail.com> yazd?:

> I am a newbee in Python. I have some problem with usage of Pyplot. I have a
> loop that creates plot in every end of it. Problem starts here: The first
> plot is fine but the second one is plotted onto the first plot. I use:
>
> plt.cla()
> plt.draw()
> plt.hold(False)
> plt.close()
> plt.clf()
>
> but nothing works. Perhaps I am having a problem with basics, please help
> me if you know something about it.
>
> Kaan
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/6a93fb69/attachment.html>

From lists at cheimes.de  Thu Jul 30 05:53:03 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 30 Jul 2009 11:53:03 +0200
Subject: Can you easy_install from your localhost?
In-Reply-To: <9c8c445f0907290857x27930acbvc5067a242e18ed17@mail.gmail.com>
References: <9c8c445f0907290857x27930acbvc5067a242e18ed17@mail.gmail.com>
Message-ID: <h4rqi0$2ss$1@ger.gmane.org>

Ronn Ross schrieb:
> I have a package i would like to store locally. If it is stored locally can
> I do something like ' easy_install http://localhost/package ' ? Thanks

You can do:

  easy_install /path/to/package-0.1.tar.gz

or you can put your packages into
/some/directory/simple/packagename/package-0.1.tar.gz and do:

  easy_install -i file:///some/directory packagename

Christian



From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 30 06:10:36 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 30 Jul 2009 10:10:36 GMT
Subject: gamma approximation : what is module cmath and where is it 
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<mailman.3932.1248928456.8015.python-list@python.org>
Message-ID: <pan.2009.07.30.10.10.36@REMOVE.THIS.cybersource.com.au>

On Wed, 29 Jul 2009 21:34:07 -0700, Chris Rebert wrote:

> The difference is that it handles complex numbers, whereas the plain
> "math" module doesn't.
> I would guess the reason there are separate modules is for performance,
> so as to avoid having to dispatch on type at runtime. But this is only a
> guess.


My understanding is that it is to avoid people who don't care about 
complex numbers being confused when math.sqrt(-1) returns 1j instead of 
raising an error.



-- 
Steven


From egcalso at gmail.com  Thu Jul 30 06:13:52 2009
From: egcalso at gmail.com (eman)
Date: Thu, 30 Jul 2009 03:13:52 -0700 (PDT)
Subject: Help on Reading Attached Image on Excel
Message-ID: <7a651be8-e653-448e-91a2-84af71c5f64d@p36g2000prn.googlegroups.com>

Anyone know how to read included images in Excel using Python?

I've tried xlrd and pyexcelerator, but i couldn't figure out how to do
it.

If anyone has experience in this, please help.

Thanks.


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 30 06:20:24 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 30 Jul 2009 10:20:24 GMT
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<mailman.3935.1248933706.8015.python-list@python.org>
Message-ID: <pan.2009.07.30.10.20.25@REMOVE.THIS.cybersource.com.au>

On Thu, 30 Jul 2009 07:01:28 +0100, Barak, Ron wrote:

> I wanted my application to "hide" the fact that it's a python script,
> and look as much as possible like it's a compiled program.

What do you think the "c" in .pyc stands for?

What it's not is a compiled to machine-code stand alone executable.


> The reason I don't just give my user a py file, is that I don't want 
> a cleaver user to change the innards of the script.

It's not the clever users you need to worry about, because they'll fix 
your bugs. It's the not-as-clever-as-they-think-they-are users you have 
to worry about. But frankly, the best way to deal with them is to make it 
absolutely clear that you don't provide free support for modified 
versions of the script, and as soon as they report a problem, you diff 
their version with the official version. If they vary, then you start 
charging them.

Before you go spending vast amounts of time and energy creating a fragile 
solution, it's worth you working out what it actually is you're trying to 
prevent. If it's just "I don't want anybody touching my precious, 
precious code!" then I have no sympathy and have no interest in helping 
you. If it's "The damn users have mucked up the script AGAIN and now they 
expect me to fix it for free!!!", then that's a social problem, not a 
technical one, and a social solution might save you a lot of wasted 
effort.




-- 
Steven


From clp2 at rebertia.com  Thu Jul 30 06:20:41 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 30 Jul 2009 03:20:41 -0700
Subject: gamma approximation : what is module cmath and where is it 
	located ?
In-Reply-To: <pan.2009.07.30.10.10.36@REMOVE.THIS.cybersource.com.au>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<mailman.3932.1248928456.8015.python-list@python.org>
	<pan.2009.07.30.10.10.36@REMOVE.THIS.cybersource.com.au>
Message-ID: <50697b2c0907300320s35658775tfacc182f16ce9711@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:10 AM, Steven
D'Aprano<steven at remove.this.cybersource.com.au> wrote:
> On Wed, 29 Jul 2009 21:34:07 -0700, Chris Rebert wrote:
>
>> The difference is that it handles complex numbers, whereas the plain
>> "math" module doesn't.
>> I would guess the reason there are separate modules is for performance,
>> so as to avoid having to dispatch on type at runtime. But this is only a
>> guess.
>
> My understanding is that it is to avoid people who don't care about
> complex numbers being confused when math.sqrt(-1) returns 1j instead of
> raising an error.

That seems a better and more plausible rationale than my guess. Kudos.

- Chris
-- 
http://blog.rebertia.com


From bieffe62 at gmail.com  Thu Jul 30 06:29:24 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 03:29:24 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
Message-ID: <41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com>

On Jul 30, 5:52?am, NighterNet <darkne... at gmail.com> wrote:
> I am trying to figure out how to send text or byte in python 3.1. I am
> trying to send data to flash socket to get there. I am not sure how to
> work it.
>
> buff= 'id=' , self.id , ':balive=False\n'
> clientSock.send(buff);

Try putting a 'b' before the constant string that you want to send:

>>> type(b'123')
<class 'bytes'>

or use something like this to convert non constant strings (with only
ASCII characters) into bytes:

>>> s = "A non-constant string : %d " % n
>>> s
'A non-constant string : 12 '
>>> type(s)
<class 'str'>
>>> b = bytes ( ord(c) for c in s )
>>> b
b'A non-constant string : 12 '

You could also use struct.pack , that in python 3.x returns bytes and
not strings. In this case you need to specify the size of the string
(extra
bytes are zero-filled):

import struct

>>> struct.pack( "30s", "A non-constant string : %d " % n )
b'A non-constant string : 12 \x00\x00\x00'



Ciao
-----
FB


From marco at sferacarta.com  Thu Jul 30 06:29:50 2009
From: marco at sferacarta.com (Marco Mariani)
Date: Thu, 30 Jul 2009 12:29:50 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <yCecm.2708$I16.503@tornado.fastwebnet.it>

r wrote:

> My adventures in Ruby.

Oh, it's you.
Good boy.
Now, why don't you have a look at javascript and come back in six months?
Or better yet, haskell and twelve months.

thanks



From wolfgang at rohdewald.de  Thu Jul 30 06:35:22 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 12:35:22 +0200
Subject: New implementation of re module
In-Reply-To: <a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<mailman.3792.1248722883.8015.python-list@python.org>
	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
Message-ID: <200907301235.22563.wolfgang@rohdewald.de>

On Tuesday 28 July 2009, Christopher Arndt wrote:
> setup(name='regex',
>     version='1.0',
>     py_modules = ['regex'],
>     ext_modules=[Extension('_regex', ['_regex.c'])],
> )
>
> Also, you need to copy "unicodedata_db.h" from the "Modules"
> directory of the Python source tree to your working directory,
> since this file apparently is not installed into the include
> directory of a Python installation.

using issue2636-20090729.zip

I have Python 2.6.2 on ubuntu 9.04

with ggc-4.3:
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
build/temp.linux-i686-2.6/_regex.o
_regex.c: In Funktion ?bmatch_context?:
_regex.c:1462: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
_regex.c:1470: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
_regex.c:1478: Fehler: Als Verringerungsoperand wird L-Wert erfordert

with gcc-4.4:
gcc-4.4 -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-
prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
build/temp.linux-i686-2.6/_regex.o
_regex.c: In function ?bmatch_context?:
_regex.c:1462: error: lvalue required as increment operand
_regex.c:1470: error: lvalue required as increment operand
_regex.c:1478: error: lvalue required as decrement operand


-- 
Wolfgang


From Ron.Barak at lsi.com  Thu Jul 30 06:42:52 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 11:42:52 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>



________________________________
From: PythonAB [mailto:python at rgbaz.eu]
Sent: Thursday, July 30, 2009 12:18
To: Barak, Ron
Cc: 'Dave Angel'; 'python-list at python.org'
Subject: Re: Run pyc file without specifying python path ?


Hi Dave,
Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.
Bye,
Ron.

Hey Ron,

What i usually do to accomplish this is compile the script to a .pyc just like you
did and then call that pyc from another script that's not compiled.
so in your case the not compiled script looks like:

#!/usr/bin/env python

import test_pyc.pyc



then run that script...

hope this helps...



alternatively you might have a look at:
http://www.pyinstaller.org/



gr
Arno
[BR] Thanks for the answer Arno. But, I wonder -

How is your suggestion, which to the user would look like:
python wrapper.py

different (from the user's point-of-view) than the following:
python test_pyc.pyc ?

I'm trying to avoide having to write python on the command line.
Of course, I could write the wrapper is bourne shell, but that interoduces other problems (especially when considering that my real application needs to parse many command line options).
.
Bye,
Ron.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/24be79c0/attachment.html>

From bieffe62 at gmail.com  Thu Jul 30 06:49:36 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 03:49:36 -0700 (PDT)
Subject: Python processors? : WAS Re: Does python have the capability for 
	driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr> 
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3939.1248945048.8015.python-list@python.org>
Message-ID: <2d8298b9-b857-4b3d-ae63-2056d80cdf7f@d4g2000yqa.googlegroups.com>

On Jul 30, 11:10?am, Christian Heimes <li... at cheimes.de> wrote:
> Martin P. Hellwig wrote:
> > Well the pyc, which I thought was the Python bytecode, is then
> > interpreted by the VM.
>
> Python is often referred as byte-code interpreted language. Most modern
> languages are interpreted languages. The list [1] is rather long.
> Technically speaking even native code is interpreted by the micro code
> of most CPUs.
>
> [1]http://en.wikipedia.org/wiki/Interpreted_language
> [2]http://en.wikipedia.org/wiki/Microcode

Once upon a time there where lisp machines, whith processors designed
to fastly execute lisp code  ... I worked with one of them for 2
years.
I wonder: has anybody thought of making a python-machine, or at least
a processor able to directly execute high-level bytecode (LLVM-like?).
I think the main feature of such a machine should be hyper-fast hash
lookup. Then dynamic memory management hardware ...

Ciao
-----
FB


From clp2 at rebertia.com  Thu Jul 30 06:57:40 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 30 Jul 2009 03:57:40 -0700
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
Message-ID: <50697b2c0907300357ld78846ch257547666a453829@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:42 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
>
>
> ________________________________
> From: PythonAB [mailto:python at rgbaz.eu]
> Sent: Thursday, July 30, 2009 12:18
> To: Barak, Ron
> Cc: 'Dave Angel'; 'python-list at python.org'
> Subject: Re: Run pyc file without specifying python path ?
>
>
> Hi Dave,
> Your solution sort of defeats my intended purpose (sorry for not divulging
> my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python script, and
> look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want a
> cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?) version of the
> application, because it'll grow the resulting file significantly, and I
> don't have the experience to know how it will run on different Linuxes.
> Bye,
> Ron.
>
> Hey Ron,
> What i usually do to accomplish this is compile the script to a .pyc just
> like you
> did and then call that pyc from another script that's not compiled.
> so in your case the not compiled script looks like:
> #!/usr/bin/env python
> import test_pyc.pyc
>
>
> then run that script...
> hope this helps...
>
>
> alternatively you might have a look at:
> http://www.pyinstaller.org/
>
>
> gr
> Arno
> [BR]?Thanks for the answer Arno. But, I wonder?-
>
> How is your suggestion, which to the user would look like:
> python wrapper.py

No, with the shebang line (and assuming execute permissions on the
file), it would look like:

./wrapper.py

(or just `wrapper.py` depending on whether the file is placed in the $PATH)

Cheers,
Chris
-- 
http://blog.rebertia.com


From python at mrabarnett.plus.com  Thu Jul 30 07:05:58 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 12:05:58 +0100
Subject: New implementation of re module
In-Reply-To: <200907301235.22563.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<mailman.3792.1248722883.8015.python-list@python.org>	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
	<200907301235.22563.wolfgang@rohdewald.de>
Message-ID: <4A717E96.3020900@mrabarnett.plus.com>

Wolfgang Rohdewald wrote:
> On Tuesday 28 July 2009, Christopher Arndt wrote:
>> setup(name='regex',
>>     version='1.0',
>>     py_modules = ['regex'],
>>     ext_modules=[Extension('_regex', ['_regex.c'])],
>> )
>>
>> Also, you need to copy "unicodedata_db.h" from the "Modules"
>> directory of the Python source tree to your working directory,
>> since this file apparently is not installed into the include
>> directory of a Python installation.
> 
> using issue2636-20090729.zip
> 
> I have Python 2.6.2 on ubuntu 9.04
> 
> with ggc-4.3:
> gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
> Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
> build/temp.linux-i686-2.6/_regex.o
> _regex.c: In Funktion ?bmatch_context?:
> _regex.c:1462: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
> _regex.c:1470: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
> _regex.c:1478: Fehler: Als Verringerungsoperand wird L-Wert erfordert
> 
> with gcc-4.4:
> gcc-4.4 -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-
> prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
> build/temp.linux-i686-2.6/_regex.o
> _regex.c: In function ?bmatch_context?:
> _regex.c:1462: error: lvalue required as increment operand
> _regex.c:1470: error: lvalue required as increment operand
> _regex.c:1478: error: lvalue required as decrement operand
> 
There are other lines which are similar, eg line 1487. Do they all give
the same/similar error with your compiler?


From masklinn at masklinn.net  Thu Jul 30 07:36:49 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 13:36:49 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>

On 30 Jul 2009, at 06:04 , alex23 wrote:
> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>> 1.) No need to use "()" to call a function with no arguments.
>> Python --> "obj.m2().m3()" --ugly
>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>> Man, i must admit i really like this, and your code will look so much
>> cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?
>
As chris pointed out, there's a method for that, to which a symbol is  
provided: `Object#method(methodname)`, which is basically equivalent  
to `getattr(object, methodname)` in Python.

>> 2.) the .each method
>> container.each{|localVar| block}
>> This method can really cleanup some ugly for loops, although i really
>> like the readability of for loops.
>
> map(lambda localVar: <block>, sequence)
>
> or:
>
> def usefully_named_func(var):
>    <block>
>    return var
>
> transformed = [usefully_named_func(v) for v in sequence]
>
The issue here is of course that `map` and comprehensions are  
transformations. `#each` exists for effectful iterations (Ruby has  
`#map` for the map operation). So the intent expressed by `#each` and  
`map` isn't the same. Furthermore and this is the most problematic  
limitation of Python here, `lambda` doesn't allow complex  
transformations due to its restrictions, so one has to switch to named  
functions which works but isn't sexy (and tends to lower readability  
imo).

>> 3.) true OOP
>> Now before you go and get all "huffy" over this statement, hear me
>> out. Python is the best language in the world. But it damn sure has
>> some warts! "len(this)" instead of "obj.length" max(that) instead of
>> [1,2,3,4,5].max().
>
> As the Zen says: '[P]racticality beats purity'. Personally, I'm not
> sure how a handful of convenient built-in functions make a language in
> which _everything is an object_ somehow "false" OO.
>
That's an interesting point, but not relevant at the end of the day:  
`foo.length` and `length(foo)` have the same "practicality". On the  
other hand Ruby can be praised for the coherence: everything's a  
method period end of the story; while Python does have a dichotomy  
between methods and functions/generic methods (whether or not that  
dichotomy bothers users is another issue).

> With max(), this is a built-in that takes _any_ iterable and an
> optional key function, and returns the highest value as per the key.
> This means that _every_ iterable object - as _well_ as every object
> that supports enough of the iterator protocol - can be handed to max()
> and a result obtained. So at best, I just need to make sure my new
> sequence-type provides the iterator protocol and viola, it works with
> max() without me having to hand-code a .max() that's specialised for
> my new type, and without Python forcing me to have a complex
> inheritance chain just to make sure I include the right
> MaxableSequence ancestor to inherit the right .max().
>
Well interestingly, Ruby works pretty much the same way. Where Python  
asks that you implement the iterator protocol to have `max` work, Ruby  
asks that you implement the `each` method (also called the Enumerable  
protocol) and mixin `Enumerable` (http://ruby-doc.org/core/classes/Enumerable.html 
). Then you get max (and min, map, etc?) "for free". Of course you're  
free to re-implement all of them manually if you wish to do so (or if  
you need those operations to return your custom collection rather than  
arrays). Enumerable is merely a convenience mixin. So there's no big  
difference here (and note that mixins aren't necessarily part of the  
inheritance chain, though they're implemented that way in Ruby).

Also, it's "voil?" not "viola" (a viola is a bowed string instrument,  
slightly bigger than a violin, whereas voil? is a french interjection  
used to call attention or suggest the appearance of something, as if  
by magic).

>> PS stay tuned for more from this series....
>
> Is this going to be more of you telling us - without any apparent
> irony whatsoever - how Ruby has some valid points after all your
> vilification last year when we said the same to you?  If so, where can
> I sign up?!
I fear I'll have to agree with that sentiment.

From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul 30 07:40:05 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 30 Jul 2009 13:40:05 +0200
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <87ljm72h04.fsf@benfinney.id.au>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<87ljm72h04.fsf@benfinney.id.au>
Message-ID: <4a718695$0$2760$426a34cc@news.free.fr>

Ben Finney a ?crit :
> dandi kain <dandi.kain at gmail.com> writes:
> 
>> What is the functionality of __ or _ , leading or trailing an object ,
>> class ot function ?

<OP>
Please note that in Python, classes and functions are objects too. But 
anyway, these underscores are part of *identifiers*, not objects 
themselves !-)
</OP>

>     foo      Ordinary name, part of public interface
>     _foo     Ordinary name, part of internal-only interface
>     __foo    Ordinary name, but will be mangled (this style used rarely)
>     __foo__  Name which is used in a special way by Python

And FWIW:

      foo_     When you want to use a reserved name for identifier (ie: 
'class_' , 'or_', 'and_' etc)


From no.email at please.post  Thu Jul 30 08:02:06 2009
From: no.email at please.post (kj)
Date: Thu, 30 Jul 2009 12:02:06 +0000 (UTC)
Subject: How to "gunzip-iterate" over a file?
References: <h4qa2g$i5v$1@reader1.panix.com>
	<mailman.3916.1248898979.8015.python-list@python.org>
	<7x8wi7j80g.fsf@ruckus.brouhaha.com>
Message-ID: <h4s23u$h6g$1@reader1.panix.com>



Robert, Paul, thanks.  That was just what I was looking for.

kynn


From user at example.net  Thu Jul 30 08:03:38 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 14:03:38 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.3951.1248953823.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<mailman.3951.1248953823.8015.python-list@python.org>
Message-ID: <4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>

Masklinn wrote:
...
> That's an interesting point, but not relevant at the end of the day:  
> `foo.length` and `length(foo)` have the same "practicality". On the  
> other hand Ruby can be praised for the coherence: everything's a  method 
> period end of the story; while Python does have a dichotomy  between 
> methods and functions/generic methods (whether or not that  dichotomy 
> bothers users is another issue).
...
how would you correct a newbie (like me) who says:

"well, the main difference between a function and a method (from the 
caller's pow) is a syntactic one:

fun(obj, arguments)

as opposed to:

obj.met(arguments)

but the effect is just about the same."

?

bye


From Ray.Joseph at CDICorp.com  Thu Jul 30 08:17:05 2009
From: Ray.Joseph at CDICorp.com (ray)
Date: Thu, 30 Jul 2009 05:17:05 -0700 (PDT)
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org> 
	<m21vo2czeb.fsf@cs.uu.nl> <468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com> 
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com> 
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com> 
	<mailman.3784.1248709156.8015.python-list@python.org>
	<b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>
	<mailman.3840.1248791727.8015.python-list@python.org>
Message-ID: <976e1fea-4f40-49be-81e1-493456fcf52d@o36g2000vbl.googlegroups.com>

> Where can I find a Python functionality like simulink ??

Stef,

I saw this at:
http://showmedo.com/videotutorials/video?name=7430000&fromSeriesID=743

Ray


From jeanmichel at sequans.com  Thu Jul 30 08:24:39 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 30 Jul 2009 14:24:39 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<mailman.3951.1248953823.8015.python-list@python.org>
	<4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
Message-ID: <4A719107.9020500@sequans.com>

superpollo wrote:
> Masklinn wrote:
> ...
>> That's an interesting point, but not relevant at the end of the day:  
>> `foo.length` and `length(foo)` have the same "practicality". On the  
>> other hand Ruby can be praised for the coherence: everything's a  
>> method period end of the story; while Python does have a dichotomy  
>> between methods and functions/generic methods (whether or not that  
>> dichotomy bothers users is another issue).
> ...
> how would you correct a newbie (like me) who says:
>
> "well, the main difference between a function and a method (from the 
> caller's pow) is a syntactic one:
>
> fun(obj, arguments)
>
> as opposed to:
>
> obj.met(arguments)
>
> but the effect is just about the same."
>
> ?
>
> bye

My suggestion

- OO programming:
length(foo) calls the foo instance(or class for some language) length method
length(bar) calls the bar instance length method, it is **not** the same 
than the foo method

- non OO programming:
length(foo) calls the length function with foo as parameter
length(bar) calls the **same** length function with the bar parameter 
(so you better make sure length is handling both foo and bar)

So the difference is definitely **not** a syntactic one, but it is true 
that the syntax obj.method() better illustrates the bind mechanism of 
the OO programming.

JM



From clp2 at rebertia.com  Thu Jul 30 08:27:12 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 30 Jul 2009 05:27:12 -0700
Subject: Python processors? : WAS Re: Does python have the capability for 
	driver development ?
In-Reply-To: <2d8298b9-b857-4b3d-ae63-2056d80cdf7f@d4g2000yqa.googlegroups.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3939.1248945048.8015.python-list@python.org>
	<2d8298b9-b857-4b3d-ae63-2056d80cdf7f@d4g2000yqa.googlegroups.com>
Message-ID: <50697b2c0907300527o37e2353vb2fa7d62e2f9ebdd@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:49 AM, Francesco Bochicchio<bieffe62 at gmail.com> wrote:
> On Jul 30, 11:10?am, Christian Heimes <li... at cheimes.de> wrote:
>> Martin P. Hellwig wrote:
>> > Well the pyc, which I thought was the Python bytecode, is then
>> > interpreted by the VM.
>>
>> Python is often referred as byte-code interpreted language. Most modern
>> languages are interpreted languages. The list [1] is rather long.
>> Technically speaking even native code is interpreted by the micro code
>> of most CPUs.
>>
>> [1]http://en.wikipedia.org/wiki/Interpreted_language
>> [2]http://en.wikipedia.org/wiki/Microcode
>
> Once upon a time there where lisp machines, whith processors designed
> to fastly execute lisp code ?... I worked with one of them for 2
> years.
> I wonder: has anybody thought of making a python-machine, or at least
> a processor able to directly execute high-level bytecode (LLVM-like?).
> I think the main feature of such a machine should be hyper-fast hash
> lookup. Then dynamic memory management hardware ...

Yes, it was considered a decade ago:
http://mail.python.org/pipermail/python-list/1999-June/004451.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From wolfgang at rohdewald.de  Thu Jul 30 08:29:07 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 14:29:07 +0200
Subject: New implementation of re module
In-Reply-To: <4A717E96.3020900@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<200907301235.22563.wolfgang@rohdewald.de>
	<4A717E96.3020900@mrabarnett.plus.com>
Message-ID: <200907301429.07850.wolfgang@rohdewald.de>

On Thursday 30 July 2009, MRAB wrote:
> There are other lines which are similar, eg line 1487. Do they all
> give the same/similar error with your compiler?

yes. The full output with gcc-4.3:


notebook:~/kmj/src$ LANG=C python setup.py  build
running build
running build_py
running build_ext
building '_regex' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
build/temp.linux-i686-2.6/_regex.o
_regex.c: In function 'bmatch_context':
_regex.c:1462: error: lvalue required as increment operand
_regex.c:1470: error: lvalue required as increment operand
_regex.c:1478: error: lvalue required as decrement operand
_regex.c:1487: error: lvalue required as decrement operand
_regex.c:1593: error: lvalue required as increment operand
_regex.c:1606: error: lvalue required as decrement operand
_regex.c:1616: error: lvalue required as increment operand
_regex.c:1625: error: lvalue required as increment operand
_regex.c:1634: error: lvalue required as decrement operand
_regex.c:1643: error: lvalue required as decrement operand
_regex.c:2036: error: lvalue required as increment operand
_regex.c:2047: error: lvalue required as increment operand
_regex.c:2059: error: lvalue required as decrement operand
_regex.c:2070: error: lvalue required as decrement operand
_regex.c:2316: error: lvalue required as increment operand
In file included from _regex.c:2431:
_regex.c: In function 'umatch_context':
_regex.c:1462: error: lvalue required as increment operand
_regex.c:1470: error: lvalue required as increment operand
_regex.c:1478: error: lvalue required as decrement operand
_regex.c:1487: error: lvalue required as decrement operand
_regex.c:1593: error: lvalue required as increment operand
_regex.c:1606: error: lvalue required as decrement operand
_regex.c:1616: error: lvalue required as increment operand
_regex.c:1625: error: lvalue required as increment operand
_regex.c:1634: error: lvalue required as decrement operand
_regex.c:1643: error: lvalue required as decrement operand
_regex.c:2036: error: lvalue required as increment operand
_regex.c:2047: error: lvalue required as increment operand
_regex.c:2059: error: lvalue required as decrement operand
_regex.c:2070: error: lvalue required as decrement operand
_regex.c:2316: error: lvalue required as increment operand
error: command 'gcc' failed with exit status 1

-- 
Wolfgang


From masklinn at masklinn.net  Thu Jul 30 08:30:48 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 14:30:48 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<mailman.3951.1248953823.8015.python-list@python.org>
	<4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
Message-ID: <AAEFAD09-9104-4B1B-A111-367BCD255752@masklinn.net>

On 30 Jul 2009, at 14:03 , superpollo wrote:
> Masklinn wrote:
> ...
>> That's an interesting point, but not relevant at the end of the  
>> day:  `foo.length` and `length(foo)` have the same "practicality".  
>> On the other hand Ruby can be praised for the coherence:  
>> everything's a  method period end of the story; while Python does  
>> have a dichotomy  between methods and functions/generic methods  
>> (whether or not that  dichotomy bothers users is another issue).
> ...
> how would you correct a newbie (like me) who says:
>
> "well, the main difference between a function and a method (from the  
> caller's pow) is a syntactic one:
>
> fun(obj, arguments)
>
> as opposed to:
>
> obj.met(arguments)
>
> but the effect is just about the same."
>
> ?
Depending on the way things are implemented, it can be very similar  
(see CLOS' generic functions, which have the same look as functions  
but dispatch based on parameter types).

In Python, the difference would be that functions don't automatically  
dispatch (you have a function for everybody, and any dispatch you  
perform based on argument types or other qualifiers has to be done  
manually) whereas methods do dispatch on the first [implied] argument  
(you execute a precise method corresponding to the object it's being  
called on).

So fun(obj, *arguments) will call the same `fun` whether `obj` is an  
int, a string or an HTTPFactory whereas obj.met(*arguments) will call  
a different `met` each time (they all have the same "unqualified" name  
[and signature if it's part of a protocol], but might very well be  
implemented completely differently). Therefore -- in python -- the  
effect isn't anywhere "just about the same".



From beldar.cat at gmail.com  Thu Jul 30 08:40:41 2009
From: beldar.cat at gmail.com (Beldar)
Date: Thu, 30 Jul 2009 05:40:41 -0700 (PDT)
Subject: Regexp problem
Message-ID: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>

Hi there!

I have a problem and i'm not very good at regular expressions.
I have a text like "lalala lalala tiruri beldar-is-listening tiruri
lalala" I need a regexp to get the 'beldar' part, the format is
'something-is-listening', i need to get the something part, use it in
my code, and then replace the whole 'something-is-listening' for
another string.

Someone can help me please? Thank you!


From nobody at nowhere.com  Thu Jul 30 08:43:29 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 30 Jul 2009 13:43:29 +0100
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <pan.2009.07.30.12.43.29.62000@nowhere.com>

On Wed, 29 Jul 2009 23:24:11 -0500, pdlemper wrote:

> The following numerical approximation for Euler's Gamma function
> is found in http://en.wikipedia.org/wiki/Lanczos_approximation
> 
> from cmath import *

> This works in Python 3.0    
>   
> But I can't figure out where it gets "cmath".    Searching the Python 
> directory reveals no more than a test_cmath.  The only cmath I can find
> is a header file in another directory  turboc++\Borland\include\
> 
> dir(cmath) reveals 23 functions overlapping the 37 functions of
> the math module.
> 
> What is cmath, where did it come from and how does it differ from
> the standard math module  ?

If you're looking for the file, it's written in C, so it's typically a
dynamic library, e.g.:

	/usr/lib/python2.5/lib-dynload/cmath.so

You won't find a cmath.py file.



From nytrokiss at gmail.com  Thu Jul 30 08:45:09 2009
From: nytrokiss at gmail.com (James Matthews)
Date: Thu, 30 Jul 2009 15:45:09 +0300
Subject: Image merging
Message-ID: <8a6b8e350907300545i48de1284h82e3c4d9d249ff8@mail.gmail.com>

Hi,

I need to create an app that takes to images and mergers them. After
googling around I have found 4 graphic library's that I can use. However
since I am new to "image programming" can you please tell me which one you
think would be the best.

The ones I found were

cairographics
PIL
Imagemagick
GraphicsMagick

Any tips?

Thanks
James

-- 
http://www.goldwatches.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/922dcff8/attachment.html>

From python at rgbaz.eu  Thu Jul 30 08:54:21 2009
From: python at rgbaz.eu (PythonAB)
Date: Thu, 30 Jul 2009 14:54:21 +0200
Subject: Run pyc file without specifying python path ?
In-Reply-To: <50697b2c0907300357ld78846ch257547666a453829@mail.gmail.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
	<50697b2c0907300357ld78846ch257547666a453829@mail.gmail.com>
Message-ID: <736F147B-47A0-4559-8FC3-4134068B5F09@rgbaz.eu>


On 30 jul 2009, at 12:57, Chris Rebert wrote:

> On Thu, Jul 30, 2009 at 3:42 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
>>
>>
>> ________________________________
>> From: PythonAB [mailto:python at rgbaz.eu]
>> Sent: Thursday, July 30, 2009 12:18
>> To: Barak, Ron
>> Cc: 'Dave Angel'; 'python-list at python.org'
>> Subject: Re: Run pyc file without specifying python path ?
>>
>>
>> Hi Dave,
>> Your solution sort of defeats my intended purpose (sorry for not  
>> divulging
>> my 'hidden agenda').
>> I wanted my application to "hide" the fact that it's a python  
>> script, and
>> look as much as possible like it's a compiled program.
>> The reason I don't just give my user a py file, is that I don't  
>> want a
>> cleaver user to change the innards of the script.
>> On the other hand, I don't want to make a compiled (freezed?)  
>> version of the
>> application, because it'll grow the resulting file significantly,  
>> and I
>> don't have the experience to know how it will run on different  
>> Linuxes.
>> Bye,
>> Ron.
>>
>> Hey Ron,
>> What i usually do to accomplish this is compile the script to  
>> a .pyc just
>> like you
>> did and then call that pyc from another script that's not compiled.
>> so in your case the not compiled script looks like:
>> #!/usr/bin/env python
>> import test_pyc.pyc
>>
>>
>> then run that script...
>> hope this helps...
>>
>>
>> alternatively you might have a look at:
>> http://www.pyinstaller.org/
>>
>>
>> gr
>> Arno
>> [BR] Thanks for the answer Arno. But, I wonder -
>>
>> How is your suggestion, which to the user would look like:
>> python wrapper.py
>
> No, with the shebang line (and assuming execute permissions on the
> file), it would look like:
>
> ./wrapper.py
>
> (or just `wrapper.py` depending on whether the file is placed in the  
> $PATH)
>
> Cheers,
> Chris
>

yes exactly, chris

you can distribute a pyc containing your program, and have the  
wrapper.py execute it

gr
Arno 


From python at mrabarnett.plus.com  Thu Jul 30 08:56:32 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 13:56:32 +0100
Subject: New implementation of re module
In-Reply-To: <200907301429.07850.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<200907301235.22563.wolfgang@rohdewald.de>	<4A717E96.3020900@mrabarnett.plus.com>
	<200907301429.07850.wolfgang@rohdewald.de>
Message-ID: <4A719880.3070300@mrabarnett.plus.com>

Wolfgang Rohdewald wrote:
> On Thursday 30 July 2009, MRAB wrote:
>> There are other lines which are similar, eg line 1487. Do they all
>> give the same/similar error with your compiler?
> 
> yes. The full output with gcc-4.3:
> 
> 
> notebook:~/kmj/src$ LANG=C python setup.py  build
> running build
> running build_py
> running build_ext
> building '_regex' extension
> gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
> Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
> build/temp.linux-i686-2.6/_regex.o
> _regex.c: In function 'bmatch_context':
> _regex.c:1462: error: lvalue required as increment operand
[snip]
> error: command 'gcc' failed with exit status 1
> 
So it complains about:

     ++(RE_CHAR*)context->text_ptr

but not about:

     ++info->repeat.count

Does this mean that the gcc compiler thinks that the cast makes it an
rvalue? I'm using Visual C++ 2008 Express Edition, which doesn't
complain. What does the C standard say?


From davea at dejaviewphoto.com  Thu Jul 30 09:02:55 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Thu, 30 Jul 2009 09:02:55 -0400
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
Message-ID: <4A7199FF.8010202@dejaviewphoto.com>

Barak, Ron wrote:
>> -----Original Message-----
>> From: Dave Angel [mailto:davea at ieee.org] 
>> Sent: Wednesday, July 29, 2009 21:05
>> To: Barak, Ron
>> Cc: 'python-list at python.org'
>> Subject: Re: Run pyc file without specifying python path ?
>>
>> Barak, Ron wrote:
>>     
>>> Hi,
>>>
>>> I wanted to make a python byte-code file executable, 
>>>       
>> expecting to be able to run it without specifying "python" on 
>> the (Linux bash) command line.
>>     
>>> So, I wrote the following:
>>>
>>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
>>>
>>> print "hello"
>>> [root at VMLinux1 python]#
>>>
>>> and made its pyc file executable:
>>>
>>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
>>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
>>> [root at VMLinux1 python]#
>>>
>>> So, I see:
>>>
>>> [root at VMLinux1 python]# file test_pyc.py*
>>> test_pyc.py:  a python script text executable
>>> test_pyc.pyc: python 2.3 byte-compiled
>>> [root at VMLinux1 python]#
>>>
>>> If I try to do the following, no problem:
>>>
>>> [root at VMLinux1 python]# python test_pyc.pyc hello
>>> [root at VMLinux1 python]#
>>>
>>> However, the following fails:
>>>
>>> [root at VMLinux1 python]# ./test_pyc.pyc
>>> -bash: ./test_pyc.pyc: cannot execute binary file
>>> [root at VMLinux1 python]#
>>>
>>> Is there a way to run a pyc file without specifying the 
>>>       
>> python path ?
>>     
>>> Bye,
>>> Ron.
>>>
>>>   
>>>       
>> I don't currently run Unix, but I think I know the problem.
>>
>> In a text file, the shell examines the first line, and if it 
>> begins #! 
>> it's assumed to point to the executable of an interpreter for 
>> that text file.  Presumably the same trick doesn't work for a 
>> .pyc file.
>>
>> Why not write a trivial wrapper.py file, don't compile it, 
>> and let that invoke the main code in the .pyc file?
>>
>> Then make wrapper.py executable, and you're ready to go.
>>
>> DaveA
>>
>>
>>     
>
> Hi Dave,
> Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.
> Bye,
> Ron. 
>   
Most of the other answers basically paraphrased my suggestion of making 
a wrapper file, not compiling it, and making it executable.  With that 
approach, the user just types   "wrapper.py" on his command line.

And wrapper.py only needs two lines, a shebang, and an import, no big 
deal if the user modifies it.  The rest of your code can be .pyc files.

Steven makes some good points.  You have to define what level of clever 
you're protecting from.  A determined hacker will get in no matter what 
you do, unless you want to ship the program in a proprietary embedded 
system, encased in epoxy.  Further, if you have an extension of .py or 
.pyc, a knowledgeable hacker will know it's probably python.

You imply you want it to run unmodifed on multiple unknown Linux 
versions.  I think that lets out binfmt solutions.  That means you need 
to test and support not only multiple Linux implementations, but 
multiple Python versions, because who knows what the user may have 
installed.  I think you need to rethink your support strategy.  And 
maybe concentrate on being able to detect change, rather than prevent it.

DaveA




From python.list at tim.thechases.com  Thu Jul 30 09:04:24 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 30 Jul 2009 08:04:24 -0500
Subject: Regexp problem
In-Reply-To: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
Message-ID: <4A719A58.4020509@tim.thechases.com>

> I have a problem and i'm not very good at regular expressions.
> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
> lalala" I need a regexp to get the 'beldar' part, the format is
> 'something-is-listening', i need to get the something part, use it in
> my code, and then replace the whole 'something-is-listening' for
> another string.


Pretty easy:

   >>> import re
   >>> s = "lalala lalala tiruri beldar-is-listening tiruri lalala"
   >>> r = re.compile(r'(\w+)-is-listening')
   >>> r.search(s).group(1)
   'beldar'
   >>> r.sub('this is a replacement', s)
   'lalala lalala tiruri this is a replacement tiruri lalala'

-tkc




From python at mrabarnett.plus.com  Thu Jul 30 09:07:51 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 14:07:51 +0100
Subject: Regexp problem
In-Reply-To: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
Message-ID: <4A719B27.8000404@mrabarnett.plus.com>

Beldar wrote:
> Hi there!
> 
> I have a problem and i'm not very good at regular expressions.
> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
> lalala" I need a regexp to get the 'beldar' part, the format is
> 'something-is-listening', i need to get the something part, use it in
> my code, and then replace the whole 'something-is-listening' for
> another string.
> 
\w+ will match a word and enclosing it in (...) will capture what was
matched:

     m = re.search(r"(\w+)-is-listening", text)
     print "Captured '%s'" % m.group(1)
     print "Matched from %d to %d" % (m.start(), m.end())


From wolfgang at rohdewald.de  Thu Jul 30 09:18:27 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 15:18:27 +0200
Subject: New implementation of re module
In-Reply-To: <4A719880.3070300@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<200907301429.07850.wolfgang@rohdewald.de>
	<4A719880.3070300@mrabarnett.plus.com>
Message-ID: <200907301518.28122.wolfgang@rohdewald.de>

On Thursday 30 July 2009, MRAB wrote:
> So it complains about:
>
>      ++(RE_CHAR*)context->text_ptr
>
> but not about:
>
>      ++info->repeat.count
>
> Does this mean that the gcc compiler thinks that the cast makes it
> an rvalue? I'm using Visual C++ 2008 Express Edition, which doesn't
> complain. What does the C standard say?

I am not really a C expert but I found some links. Most helpful:
http://developer.apple.com/DOCUMENTATION/DeveloperTools/gcc-4.0.1/gcc/C-Dialect-Options.html

(search -fnon-lvalue-assign)

so I did the conversion mentioned there. This works: 

--- _regex.c    2009-07-29 11:34:00.000000000 +0200
+++ n   2009-07-30 15:15:22.000000000 +0200
@@ -1459,7 +1459,7 @@
             if (text_ptr < (RE_CHAR*)context->slice_end && text_ptr[0] != '\n')
               {
                 context->node = node->next_1;
-                ++(RE_CHAR*)context->text_ptr;
+                ++*(RE_CHAR**)&context->text_ptr;
             } else
                 context = reject_context(state, context);
             break;


-- 
Wolfgang


From wfluro at gmail.com  Thu Jul 30 09:19:29 2009
From: wfluro at gmail.com (ulf)
Date: Thu, 30 Jul 2009 06:19:29 -0700 (PDT)
Subject: Python ctypes on win64
References: <f415d834-b2ac-4036-afb1-a12c79480eb4@i6g2000yqj.googlegroups.com>
	<h4dlvk$2is$1@panix3.panix.com>
Message-ID: <433d4958-81e4-4d5f-be51-9d1b2170d1eb@c2g2000yqi.googlegroups.com>

On Jul 25, 3:09?am, a... at pythoncraft.com (Aahz) wrote:
> In article <f415d834-b2ac-4036-afb1-a12c79480... at i6g2000yqj.googlegroups.com>,
Thanks, I'll try there.

>
> ulf ?<wfl... at gmail.com> wrote:
>
> >Does anybody know if python includes a win64 version ofctypes?
>
> >According to the documentation it should be included - at least
> >there's no special remarks for win64, and I haven't found any recent
> >notes saying that it shouldn't work on win64. Yet it looks like both
> >the installer from Python.org and from ActiveState.com have disabled
> >it.
>
> Nobody seems to have followed up to this, you may have better luck on
> the capi-sig mailing list.
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "At Resolver we've found it useful to short-circuit any doubt and just ? ? ? ?
> refer to comments in code as 'lies'. :-)"
> --Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22



From davea at ieee.org  Thu Jul 30 09:20:45 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 09:20:45 -0400
Subject: Does python have the capability for driver development ?
In-Reply-To: <sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
Message-ID: <4A719E2D.708@ieee.org>

Martin P. Hellwig wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Michel 
> Claveau - MVP wrote:
>> Hi!
>>
>>> Python is interpreted
>>
>> No. Python is compiled (--> .pyc)
>> But the term "to compile" is not always unambiguous...
>> And the notion of "compiler" is not attached to Python (the 
>> language), but is attached to the implementation.
>>
>> @+
>>
>> MCI
>
> Well the pyc, which I thought was the Python bytecode, is then 
> interpreted by the VM.
>
As Michel says, "to compile" is not always unambiguous.  My definition 
includes a one-way transformation from human-readable source text into 
something that can be more efficiently interpreted by other code, or by 
hardware.  The compiler really doesn't care whether the machine it's 
targeting is real or virtual.

The CPython implementation of Python compiles the source text into a 
bytecode file, with extension .pyc.    That certainly is a compilation 
step.  Followed (much) later by an interpreted one.

To pick a specific implementation of C++,  Microsoft C++ compiles C++ 
source text into an "executable file,"  with extension .exe  (I'm 
ignoring little details, like the linker).  That's a compilation step.  
Then the exe file is (later) interpreted by the microcode on the Pentium 
chip.

As far as I know, nobody has yet built a microcode implementation of a 
Python VM (Virtual Machine).  Nor have I seen one for the Java VM.  
However, in the early 80's there was a microcode implementation of the 
P-system VM.  It was never a commercial success, but it existed.  And 
there have been at least three Forth machines, where the hardware itself 
was designed to support the language's VM.  No microcode at all.

DaveA


From wolfgang at rohdewald.de  Thu Jul 30 09:24:28 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 15:24:28 +0200
Subject: New implementation of re module
In-Reply-To: <200907301518.28122.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<4A719880.3070300@mrabarnett.plus.com>
	<200907301518.28122.wolfgang@rohdewald.de>
Message-ID: <200907301524.28703.wolfgang@rohdewald.de>

On Thursday 30 July 2009, Wolfgang Rohdewald wrote:
> so I did the conversion mentioned there. This works:

I actually do not know if it works - but it compiles.

-- 
Wolfgang


From beldar.cat at gmail.com  Thu Jul 30 09:32:59 2009
From: beldar.cat at gmail.com (Beldar)
Date: Thu, 30 Jul 2009 06:32:59 -0700 (PDT)
Subject: Regexp problem
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
	<mailman.3961.1248959276.8015.python-list@python.org>
Message-ID: <30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>

On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Beldar wrote:
> > Hi there!
>
> > I have a problem and i'm not very good at regular expressions.
> > I have a text like "lalala lalala tiruri beldar-is-listening tiruri
> > lalala" I need a regexp to get the 'beldar' part, the format is
> > 'something-is-listening', i need to get the something part, use it in
> > my code, and then replace the whole 'something-is-listening' for
> > another string.
>
> \w+ will match a word and enclosing it in (...) will capture what was
> matched:
>
> ? ? ?m = re.search(r"(\w+)-is-listening", text)
> ? ? ?print "Captured '%s'" % m.group(1)
> ? ? ?print "Matched from %d to %d" % (m.start(), m.end())

Ok, thank you all, it was very helpful!


From ccurvey at gmail.com  Thu Jul 30 09:35:46 2009
From: ccurvey at gmail.com (Chris Curvey)
Date: Thu, 30 Jul 2009 06:35:46 -0700 (PDT)
Subject: PyPDF and print restrictions
References: <90034475-cf07-4a57-b8cf-ec2949e0e544@d23g2000vbm.googlegroups.com>
Message-ID: <13cc96b6-7c1b-4835-b711-eabedb4d6442@f10g2000vbf.googlegroups.com>

On Jul 27, 4:16?pm, Chris Curvey <ccur... at gmail.com> wrote:
> Has anyone out there been able to enforce print restrictions on a PDF
> document by usingPyPDF? The documentation for "encrypt" states:
>
> ?# @param user_pwd The "user password", which allows for opening and
> reading
> ?# the PDF file with the restrictions provided.
>
> But there is no parameter for providing a restriction, and I can't
> find a reference to any kind of restriction besides this comment in
> the docs.
>
> Thanks in advance!

I found some (I think old-ish) documentation on encryption and
permissions (of course, I've lost the link).  I think there are
additional permissions that have been implemented since the doc that I
found, but this patch works for me.

Index: C:/Documents and Settings/ccurvey/PyPDF/pyPdf/pdf.py
===================================================================
--- C:/Documents and Settings/ccurvey/PyPDF/pyPdf/pdf.py	(revision 1)
+++ C:/Documents and Settings/ccurvey/PyPDF/pyPdf/pdf.py	(revision 2)
@@ -118,7 +118,10 @@
     # @param use_128bit Boolean argument as to whether to use 128bit
     # encryption.  When false, 40bit encryption will be used.  By
default, this
     # flag is on.
-    def encrypt(self, user_pwd, owner_pwd = None, use_128bit = True):
+    # @param perm_mask bitmask of the permissions that should be
granted.
+    # Defaults to -1, which is "everything permitted"
+    def encrypt(self, user_pwd, owner_pwd = None, use_128bit = True,
+                perm_mask=-1):
         import md5, time, random
         if owner_pwd == None:
             owner_pwd = user_pwd
@@ -130,8 +133,8 @@
             V = 1
             rev = 2
             keylen = 40 / 8
-        # permit everything:
-        P = -1
+
+        P = perm_mask
         O = ByteStringObject(_alg33(owner_pwd, user_pwd, rev,
keylen))
         ID_1 = md5.new(repr(time.time())).digest()
         ID_2 = md5.new(repr(random.random())).digest()
Index: C:/Documents and Settings/ccurvey/PyPDF/pyPdf/__init__.py
===================================================================
--- C:/Documents and Settings/ccurvey/PyPDF/pyPdf/__init__.py
(revision 1)
+++ C:/Documents and Settings/ccurvey/PyPDF/pyPdf/__init__.py
(revision 2)
@@ -1,2 +1,11 @@
 from pdf import PdfFileReader, PdfFileWriter
+
+PERM_NONE = 0
+PERM_PRINT = 2
+PERM_MODIFY = 4
+PERM_COPY_TEXT = 8
+PERM_ANNOTATE = 16
+
+PERM_ALL = PERM_PRINT | PERM_MODIFY | PERM_COPY_TEXT | PERM_ANNOTATE
+
 __all__ = ["pdf"]


From marcusw at cox.net  Thu Jul 30 09:38:49 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Thu, 30 Jul 2009 09:38:49 -0400
Subject: Regexp problem
In-Reply-To: <30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
	<mailman.3961.1248959276.8015.python-list@python.org>
	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
Message-ID: <h4s7pm$rgr$1@adenine.netfront.net>

On 7/30/2009 9:32 AM, Beldar wrote:
> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> Beldar wrote:
>>> Hi there!
>>> I have a problem and i'm not very good at regular expressions.
>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>> 'something-is-listening', i need to get the something part, use it in
>>> my code, and then replace the whole 'something-is-listening' for
>>> another string.
>> \w+ will match a word and enclosing it in (...) will capture what was
>> matched:
>>
>>      m = re.search(r"(\w+)-is-listening", text)
>>      print "Captured '%s'" % m.group(1)
>>      print "Matched from %d to %d" % (m.start(), m.end())
> 
> Ok, thank you all, it was very helpful!
Wow, I really need to learn more about regexp...
Any tutorials you guys can recommend?

Marcus


From piet at cs.uu.nl  Thu Jul 30 09:39:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 30 Jul 2009 15:39:35 +0200
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <m21vnye1d4.fsf@cs.uu.nl>

>>>>> MRAB <python at mrabarnett.plus.com> (M) wrote:

>M> Hi all,
>M> I've been working on a new implementation of the re module. The details
>M> are at http://bugs.python.org/issue2636, specifically from
>M> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>M> Python 2.6 on Windows if you want to try it out.

>M> I'm interested in how fast it is generally, compared with the current re
>M> module, but especially when faced with those 'pathological' regular
>M> expressions which seem to take a long time to finish, for example:

>M>     re.search(r"^(.+|D)*A$", "x" * 25 + "B")

>M> which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs
>M> with this new implementation.

Is this version also going to use the Thompson approach?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From martin.hellwig at dcuktec.org  Thu Jul 30 09:43:26 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 14:43:26 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <mailman.3963.1248960056.8015.python-list@python.org>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
Message-ID: <uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>

Dave Angel wrote:
<cut definition/interpretation of compiling>
Ah yes, we thread on the territory of word definition and difference in 
interpretation. Any argument is doomed to fail if not agreed or at least 
taken in perspective of the terminology used by users.

I could be (well it is quite likely) wrong in my interpretation of the 
terminology, but here goes it anyway:

Machine Code:
Whatever the machine executes, it could be that the CPU uses an 
abstraction of microcode to do this but from the perspective of the 
user, this is all done in the same 'black box'

Compiling:
Translate words/symbols/mnemonics to machine code, which than can be 
either loaded, linked and executed by an OS or read and executed by the 
BIOS.

Interpreted:
Instructions which can be fed to a previous compiled program that is 
able to dynamically change its execution and flow without the need to 
recompile itself.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From piet at cs.uu.nl  Thu Jul 30 09:45:44 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 30 Jul 2009 15:45:44 +0200
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
	<m2fxcfefu2.fsf@cs.uu.nl>
	<8cb1ba65-be71-49b7-8955-54c17f351a40@w6g2000yqw.googlegroups.com>
Message-ID: <m2ws5qcmif.fsf@cs.uu.nl>

>>>>> Carl Banks <pavlovevidence at gmail.com> (CB) wrote:

>CB> On Jul 29, 7:14?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>>> >>>>> Carl Banks <pavlovevide... at gmail.com> (CB) wrote:
>>> >CB> On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
>>> >>> I'm looking to run a process with a limit of 3 instances, but each
>>> >>> execution is over a crontab interval. I've been investigating the
>>> >>> threading module and using daemons to limit active thread objects, but
>>> >>> I'm not very successful at grasping the documentation.
>>> 
>>> >>> Is it possible to do what I'm trying to do and if so anyone know of a
>>> >>> useful example to get started?
>>> >CB> It seems like you want to limit the number of processes to three; the
>>> >CB> threading module won't help you there because it deals with threads
>>> >CB> within a single process.
>>> >CB> What I'd do is to simply run the system ps to see how many processes
>>> >CB> are running (ps is pretty versatile on most systems and can find
>>> >CB> specifically targeted processes like you program), and exit if there
>>> >CB> are already three.
>>> 
>>> That will surely run into some race conditions.

>CB> What, the OS might not have gotten around to update the process table
>CB> to include a process started minutes ago?  (He said he was starting
>CB> the processes over crontab intervals, not that he communicated what he
>CB> wanted well.)

No but between the time you get the ps output and decide not to start a
new process one of the processes might have exited. As I said it
probably is not a big deal, but you (he) should be aware of it I think.

The other possible race condition: two processes starting at
approximately the same time and both not detecting the other will
probably not occur because of the time distance between starting the
processes by cron. Unless the system is so busy that ps takes a loooong
time. 

The problem is similar to the sleeping barber problem (3 sleeping
barbers actually).
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From davea at ieee.org  Thu Jul 30 09:53:31 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 09:53:31 -0400
Subject: gamma approximation : what is module cmath and where is it located
	?
In-Reply-To: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <4A71A5DB.60409@ieee.org>

pdlemper at earthlink.net wrote:
> from cmath import *
>  
> <snip>
> What is cmath, where did it come from and how does it differ from
> the standard math module  ?
>
> Dave WB3DWE
>                                    I saw the number 4 in silver,  Guido
>                                      (apologies to Wm Carlos Williams)
>
>   

I'm surprised that with all the responses, nobody has pointed out the 
dangers involved in using
     from cmath import *

In general, this form of import is discouraged.   I presume there's no 
problem if you're not also importing 'math' and all your calls are 
intending to be for the complex versions.  But if you're mixing things 
up, consider using the more conventional
     import  cmath

and using cmath.   as a prefix before the function calls.

DaveA



From metolone+gmane at gmail.com  Thu Jul 30 09:56:07 2009
From: metolone+gmane at gmail.com (Mark Tolonen)
Date: Thu, 30 Jul 2009 06:56:07 -0700
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
Message-ID: <h4s8pm$g3g$1@ger.gmane.org>


"NighterNet" <darkneter at gmail.com> wrote in message 
news:55aba832-df6d-455f-bf34-04d37eb061cd at i4g2000prm.googlegroups.com...
>I am trying to figure out how to send text or byte in python 3.1. I am
> trying to send data to flash socket to get there. I am not sure how to
> work it.
>
> buff= 'id=' , self.id , ':balive=False\n'
> clientSock.send(buff);
> -- 
> http://mail.python.org/mailman/listinfo/python-list
>

Python 3.1 strings are Unicode (think characters not bytes).  When writing 
to files, sockets, etc. bytes must be used.  Unicode strings have an 
encode() method, where you can specify an appropriate encoding (ascii, 
latin-1, windows-1252, utf-8, etc.):

    clientSock.send(buff.encode('ascii'))

When reading from the socket, you can decode() the byte strings back into 
Unicode strings.

    data = clientSock.recv(1024).decode('ascii')

-Mark




From bieffe62 at gmail.com  Thu Jul 30 10:11:24 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 07:11:24 -0700 (PDT)
Subject: No PyPI search for 3.x compatible packages
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
Message-ID: <d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>

On 30 Lug, 01:55, Neil Hodgson <nyamatongwe+thun... at gmail.com> wrote:
> ? ?There appears to be no way to search PyPI for packages that are
> compatible with Python 3.x. There are classifiers for 'Programming
> Language' including 'Programming Language :: Python :: 3' but that seems
> to be for implementation language since there are so many packages that
> specify C. There are a total of 109 packages classified with Python ::
> [3, 3.0, 3.1] out of a total of 4829 packages.http://pypi.python.org/pypi?:action=browse&show=all&c=214&c=533
>
> ? ?The search box appears to search for any word entered so a search
> like "xml 3.0" or "xml AND 3.0" does not help.
>
> ? ?Some packages include version information in the Py Version column of
> their download lists or embedded in the download file names. Projects
> are often constrained to a particular set of Python versions so need to
> choose packages that will work with those versions. It would be helpful
> if PyPI made this information more visible and searchable.
>
> ? ?Neil

Are you sure? I note that for example pygtk has as language tags both
C and python. So maybe a C extension
for python3 would have both C and python 3 as language tags.

I suspect that the 109 packages you found are the only ones obf the
4829 which works with python3 (but I hope
to be wrong ).

Ciao
-----
FB



From peter at peter-b.co.uk  Thu Jul 30 10:17:52 2009
From: peter at peter-b.co.uk (Peter Brett)
Date: Thu, 30 Jul 2009 15:17:52 +0100
Subject: Regexp problem
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
	<mailman.3961.1248959276.8015.python-list@python.org>
	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
	<h4s7pm$rgr$1@adenine.netfront.net>
Message-ID: <we1mprbidzlb.fsf@ssclt003.ee.surrey.ac.uk>

Marcus Wanner <marcusw at cox.net> writes:

> On 7/30/2009 9:32 AM, Beldar wrote:
>> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>>> Beldar wrote:
>>>> Hi there!
>>>> I have a problem and i'm not very good at regular expressions.
>>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>>> 'something-is-listening', i need to get the something part, use it in
>>>> my code, and then replace the whole 'something-is-listening' for
>>>> another string.
>>> \w+ will match a word and enclosing it in (...) will capture what was
>>> matched:
>>>
>>>      m = re.search(r"(\w+)-is-listening", text)
>>>      print "Captured '%s'" % m.group(1)
>>>      print "Matched from %d to %d" % (m.start(), m.end())
>>
>> Ok, thank you all, it was very helpful!
> Wow, I really need to learn more about regexp...
> Any tutorials you guys can recommend?

I have to confess that after fiddling with regexps for quite a while
with no great success, I learnt the hard (and best) way, i.e. using
them to write something vile and horrible. [*] I commend this path to
you also. ;-)

Cheers,

                              Peter

[*] http://git.gpleda.org/?p=gaf.git;a=blob;f=libgeda/desktop-i18n;h=6fab9b85b

-- 
Peter Brett <peter at peter-b.co.uk>
Remote Sensing Research Group
Surrey Space Centre


From p.f.moore at gmail.com  Thu Jul 30 10:20:10 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Thu, 30 Jul 2009 15:20:10 +0100
Subject: No PyPI search for 3.x compatible packages
In-Reply-To: <d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
	<d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
Message-ID: <79990c6b0907300720s3a2ad4a8lf49bc265b653f55f@mail.gmail.com>

2009/7/30 Francesco Bochicchio <bieffe62 at gmail.com>:
> On 30 Lug, 01:55, Neil Hodgson <nyamatongwe+thun... at gmail.com> wrote:
>> ? ?There appears to be no way to search PyPI for packages that are
>> compatible with Python 3.x. There are classifiers for 'Programming
>> Language' including 'Programming Language :: Python :: 3' but that seems
>> to be for implementation language since there are so many packages that
>> specify C. There are a total of 109 packages classified with Python ::
>> [3, 3.0, 3.1] out of a total of 4829 packages.http://pypi.python.org/pypi?:action=browse&show=all&c=214&c=533
>>
>> ? ?The search box appears to search for any word entered so a search
>> like "xml 3.0" or "xml AND 3.0" does not help.
>>
>> ? ?Some packages include version information in the Py Version column of
>> their download lists or embedded in the download file names. Projects
>> are often constrained to a particular set of Python versions so need to
>> choose packages that will work with those versions. It would be helpful
>> if PyPI made this information more visible and searchable.
>>
>> ? ?Neil
>
> Are you sure? I note that for example pygtk has as language tags both
> C and python. So maybe a C extension
> for python3 would have both C and python 3 as language tags.
>
> I suspect that the 109 packages you found are the only ones obf the
> 4829 which works with python3 (but I hope
> to be wrong ).

Also, of course, they may not be the only ones that work, but merely
the only ones where the author has checked they work and tagged the
entry. It's quite possible that some packages will work unmodified...

Paul.


From kwatch at gmail.com  Thu Jul 30 10:30:25 2009
From: kwatch at gmail.com (kwatch)
Date: Thu, 30 Jul 2009 07:30:25 -0700 (PDT)
Subject: [ANN] pyKook 0.0.2 - a simple build tool similar to Make or Ant
Message-ID: <c0c0453c-c4ca-47a3-bf76-d2b7e2fad7ff@b25g2000prb.googlegroups.com>


Hi,

I have released pyKook 0.0.2.
http://pypi.python.org/pypi/Kook/0.0.2
http://www.kuwata-lab.com/kook/
http://www.kuwata-lab.com/kook/pykook-users-guide.html


Overview
--------

pyKook is a simple build tool similar to Make, Ant, Rake, or SCons.
pyKook regards software project as cooking.
Terms used in pyKook are cooking terms.
For example:

    cookbook    -  Makefile
    product     -  target file
    ingredient  -  source file
    recipe      -  how to create target from source
    spices      -  command-line options for recipe


Cookbook (= Makefile) is written in pure Python.
You can write any statements or expressions in cookbook.

NOTICE: pyKook is under alpha release. Spec and features may be
changed
in the future without previous announcement.


Example
-------

Example of cookbook (Kookbook.py):

    --------------------------------------------------
    ##
    ## properties
    ##
    cc     = prop('cc',     'gcc')
    cflags = prop('cflags', '-g -Wall')


    ##
    ## recipes
    ##
    @ingreds("hello")
    def task_all(c):
        pass

    @product("hello")
    @ingreds("hello.o")
    def file_command(c):
        """generates hello command"""
        system(c%"$(cc) $(cflags) -o $(product) $(ingred)")

    @product("*.o")
    @ingreds("$(1).c", if_exists("$(1).h"))
    def file_ext_o(c):
        """compile '*.c' and '*.h'"""
        system(c%"$(cc) $(cflags) -c $(1).c")

    def task_clean(c):
        rm_f("*.o")
    --------------------------------------------------


Exampe of result:

    ==================================================
    bash> ls
    Kookbook.py   hello.c    hello.h

    bash> pykook -l
    Properties:
      cc                  : 'gcc'
      cflags              : '-g -Wall'

    Task recipes:
      all                 : cook all products
      clean               : remove by-products

    File recipes:
      hello               : generates hello command
      *.o                 : compile '*.c' and '*.h'

    (Tips: you can set 'kook_default_product' variable in your
kookbook.)

    bash> pykook all           # or, pykook --cc=gcc4 all
    ### *** hello.o (func=file_ext_o)
    $ gcc -g -Wall -c hello.c
    ### ** hello (func=file_command)
    $ gcc -g -Wall -o hello hello.o
    ### * all (func=task_all)
    ==================================================


See users-guide for more details.
http://www.kuwata-lab.com/kook/pykook-users-guide.html


Enhancements, Changes, Bug fixes sice 0.0.1
-------------------------------------------


Enhancements:

- Python 3 support.

- Add 'kk' script which is shortcat for kk command.


Changes:

- Decorator '@cmdopts()' is renamed to '@spices()', and
  there is no need to call parse_cmdopts().

      ### prev version
      @cmdopts('-v: verbose', '-f file: filename')
      def task_example(c, *args):
          opts, rests = c.parse_cmdopts(args)
          verbose = opts.get('v', False):
          fileame = opts.get('f', None)

      ### since this release (0.0.2)
      @spices('-v: verbose', '-f file: filename')
      def task_example(c, *args, *kwargs):
          opts, rests = kwarts, args
          verbose = opts.get('v', False):
          fileame = opts.get('f', None)

- Remove 'pyk' script

- Testing library is changed from Python's unittest library
  into 'test/oktest.py'.


Bugfixes:

- glob2() now recognizes files on current directory.



Have fun!

--
regards,
makoto kuwata


From davea at ieee.org  Thu Jul 30 10:30:55 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 10:30:55 -0400
Subject: Does python have the capability for driver development ?
In-Reply-To: <uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>	<mailman.3963.1248960056.8015.python-list@python.org>
	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
Message-ID: <4A71AE9F.2000900@ieee.org>

Martin P. Hellwig wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
> <cut definition/interpretation of compiling>
> Ah yes, we thread on the territory of word definition and difference 
> in interpretation. Any argument is doomed to fail if not agreed or at 
> least taken in perspective of the terminology used by users.
>
> I could be (well it is quite likely) wrong in my interpretation of the 
> terminology, but here goes it anyway:
>
> Machine Code:
> Whatever the machine executes, it could be that the CPU uses an 
> abstraction of microcode to do this but from the perspective of the 
> user, this is all done in the same 'black box'
>
> Compiling:
> Translate words/symbols/mnemonics to machine code, which than can be 
> either loaded, linked and executed by an OS or read and executed by 
> the BIOS.
>
> Interpreted:
> Instructions which can be fed to a previous compiled program that is 
> able to dynamically change its execution and flow without the need to 
> recompile itself.
>
Depending on the level of understanding of the user, plus his history 
and his biases, he will include more or less in his "black box."  In the 
old days, microcode was not "on-chip" but stored separately in control 
memory.  And on many machines, it was changeable at will.

To many users these days, the entire system including software is a 
black box, which gradually breaks down (gets slow, runs out of space, 
crashes a lot) and must be replaced.  They don't distinguish operating 
system from application, real memory from virtual, or viruses from 
bugs.  But of course those users wouldn't be participating in this 
discussion.

My background includes specifying hardware instruction sets and 
architecture.  And writing microcode for multiple machines.  And writing 
parts of compilers, interpreters, assemblers, and so on.  And 
microcoding interpreters.  And hooking into compilers to modify how they 
would generate code.   And hooking into runtimes to test running code in 
realtime.

So I tend to have very flexible definition of compiler and interpreter.  
Probably the only reason I jumped in here was the unmentioned bias that 
somehow a compiler is superior to an interpreter.

I think I'd better extend my definition of compilation.  It's a step 
that's statically taken over a series of instructions (not necessarily 
text source), that transforms it into a form closer to the targeted 
enviromment, real or virtual. Most C++ compilers have two compilers 
operating serially, the first to turn the source code into an 
intermediate form (like byte code), and the second to generate what is 
commonly called "machine code."  The second part of course is duplicated 
for each different target processor.

So Java is compiled into byte code, and the typical java VM then 
compiles that piecewise into machine code (so called JIT compiling, for 
just in time).

BTW, interpreters don't have to be written in a compiled language.


Anyway, I don't object to your definitions.  We all have different 
perspectives.

DaveA



From Ron.Barak at lsi.com  Thu Jul 30 10:47:37 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 15:47:37 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <4A7199FF.8010202@dejaviewphoto.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26D1@enbmail01.lsi.com>

 

> -----Original Message-----
> From: Dave Angel [mailto:davea at dejaviewphoto.com] 
> Sent: Thursday, July 30, 2009 16:03
> To: Barak, Ron
> Cc: 'Dave Angel'; 'python-list at python.org'
> Subject: RE: Run pyc file without specifying python path ?
> 
> Barak, Ron wrote:
> >> -----Original Message-----
> >> From: Dave Angel [mailto:davea at ieee.org]
> >> Sent: Wednesday, July 29, 2009 21:05
> >> To: Barak, Ron
> >> Cc: 'python-list at python.org'
> >> Subject: Re: Run pyc file without specifying python path ?
> >>
> >> Barak, Ron wrote:
> >>     
> >>> Hi,
> >>>
> >>> I wanted to make a python byte-code file executable,
> >>>       
> >> expecting to be able to run it without specifying "python" on the 
> >> (Linux bash) command line.
> >>     
> >>> So, I wrote the following:
> >>>
> >>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
> >>>
> >>> print "hello"
> >>> [root at VMLinux1 python]#
> >>>
> >>> and made its pyc file executable:
> >>>
> >>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> >>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> >>> [root at VMLinux1 python]#
> >>>
> >>> So, I see:
> >>>
> >>> [root at VMLinux1 python]# file test_pyc.py*
> >>> test_pyc.py:  a python script text executable
> >>> test_pyc.pyc: python 2.3 byte-compiled
> >>> [root at VMLinux1 python]#
> >>>
> >>> If I try to do the following, no problem:
> >>>
> >>> [root at VMLinux1 python]# python test_pyc.pyc hello
> >>> [root at VMLinux1 python]#
> >>>
> >>> However, the following fails:
> >>>
> >>> [root at VMLinux1 python]# ./test_pyc.pyc
> >>> -bash: ./test_pyc.pyc: cannot execute binary file
> >>> [root at VMLinux1 python]#
> >>>
> >>> Is there a way to run a pyc file without specifying the
> >>>       
> >> python path ?
> >>     
> >>> Bye,
> >>> Ron.
> >>>
> >>>   
> >>>       
> >> I don't currently run Unix, but I think I know the problem.
> >>
> >> In a text file, the shell examines the first line, and if 
> it begins 
> >> #!
> >> it's assumed to point to the executable of an interpreter for that 
> >> text file.  Presumably the same trick doesn't work for a .pyc file.
> >>
> >> Why not write a trivial wrapper.py file, don't compile it, and let 
> >> that invoke the main code in the .pyc file?
> >>
> >> Then make wrapper.py executable, and you're ready to go.
> >>
> >> DaveA
> >>
> >>
> >>     
> >
> > Hi Dave,
> > Your solution sort of defeats my intended purpose (sorry 
> for not divulging my 'hidden agenda').
> > I wanted my application to "hide" the fact that it's a 
> python script, and look as much as possible like it's a 
> compiled program.
> > The reason I don't just give my user a py file, is that I 
> don't want a cleaver user to change the innards of the script.
> > On the other hand, I don't want to make a compiled 
> (freezed?) version of the application, because it'll grow the 
> resulting file significantly, and I don't have the experience 
> to know how it will run on different Linuxes.
> > Bye,
> > Ron. 
> >   

Hi Dave,

> Most of the other answers basically paraphrased my suggestion 
> of making a wrapper file, not compiling it, and making it 
> executable.  With that 
> approach, the user just types   "wrapper.py" on his command line.
> 
> And wrapper.py only needs two lines, a shebang, and an 
> import, no big deal if the user modifies it.  The rest of 
> your code can be .pyc files.
> 
> Steven makes some good points.  You have to define what level 
> of clever you're protecting from.  A determined hacker will 

The clever I try to guard against is not at hacker level, just the curios worker.

> get in no matter what you do, unless you want to ship the 
> program in a proprietary embedded system, encased in epoxy.  
> Further, if you have an extension of .py or .pyc, a 
> knowledgeable hacker will know it's probably python.

Granted, but the user will know that from the user manual anyway :-)

> 
> You imply you want it to run unmodifed on multiple unknown 
> Linux versions.  I think that lets out binfmt solutions.  

Actually, no: I know the set of Linuxes my users are likely to have.

> That means you need to test and support not only multiple 
> Linux implementations, but multiple Python versions, because 
> who knows what the user may have installed.  I think you need 
> to rethink your support strategy.  And maybe concentrate on 
> being able to detect change, rather than prevent it.
> 
> DaveA
> 
> 

Thanks for the helpful suggestions.
Ron.
 

From invalid at invalid  Thu Jul 30 10:50:47 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 09:50:47 -0500
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<mailman.3959.1248959035.8015.python-list@python.org>
Message-ID: <tJWdnXjaWJnaLuzXnZ2dnUVZ_jdi4p2d@posted.visi>

On 2009-07-30, Dave Angel <davea at dejaviewphoto.com> wrote:

> Steven makes some good points.  You have to define what level
> of clever you're protecting from.  A determined hacker will
> get in no matter what you do, unless you want to ship the
> program in a proprietary embedded system, encased in epoxy.

That won't stop a dedicated reverse-engineering effort.  It
might take an X-ray machine, machine tools, various nasty
chemicals, and quite a bit of skill and patience -- but it can
be done.

> Further, if you have an extension of .py or .pyc, a
> knowledgeable hacker will know it's probably python.
>
> You imply you want it to run unmodifed on multiple unknown
> Linux versions.  I think that lets out binfmt solutions.  That
> means you need to test and support not only multiple Linux
> implementations, but multiple Python versions, because who
> knows what the user may have installed.  I think you need to
> rethink your support strategy.  And maybe concentrate on being
> able to detect change, rather than prevent it.

Or even being able to benefit from change. :)

-- 
Grant Edwards                   grante             Yow! FROZEN ENTREES may
                                  at               be flung by members of
                               visi.com            opposing SWANSON SECTS ...


From sajmikins at gmail.com  Thu Jul 30 10:52:46 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 30 Jul 2009 10:52:46 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
	<4A709B77.9080209@ieee.org>
	<77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
Message-ID: <50f98a4c0907300752mbabd920ma208ca6a0b8f69f2@mail.gmail.com>

On Wed, Jul 29, 2009 at 3:10 PM, Omer Khalid<Omer.Khalid at cern.ch> wrote:
> Hi Dave,
>
> Thanks for your reply. I actually didn't cut and paste my code as it was
> dispersed in different places, i typed the logic behind my code in the email
> (and obiviously made some typos, indentations is some thing else) but my

Please, do not do  that.  It's very difficult to debug code that
hasn't been seen.  The code you posted has numerous problems (that
likely have nothing to do with your actual problem.)

If you're going to post code, try to recreate the issue with a small
runnable script.  If you can't do that, as it sounds like it would be
difficult in this case as your code is dispersed in different places,
at least post the relevant portions of the actual code.  Don't
re-type.

> real code does not have these problems as my application runs fine with out
> errors...
>
> Except that the line where i want to update the value doesn't get updated
> and no exception is thrown. What's surprising for me is that i am doing the
> same thing in hundreds of places in my 3k+ line code but by some reason this
> part doesn't work...
>
> As far as the global variables are concerned, i am using them in other
> places too and didn't see any problems.
>
> I think some thing else is going on here as the statement above and below my
> modified lines get executed.

If the statements above and below that line(s) are executed, then that
line is certainly being executed as well.

Try introducing some additional print statements to verify your mental
model of what's happening:

    # set it to 1
    print jobs
    print jobs[index]
    print jobs[index]['v']
    jobs[index]['v'] = 1
    print jobs
    print jobs[index]
    print jobs[index]['v']
    print "Set to 1"

> Is there a way in Python to debug memory address or to see where in memory
> this object is stored, and is there a lock on it or else?

You are barking up the wrong tree.  Somewhere in your code you're
doing something silly that's causing your issue.


From ben+python at benfinney.id.au  Thu Jul 30 10:53:35 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 31 Jul 2009 00:53:35 +1000
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
Message-ID: <87vdlate6o.fsf@benfinney.id.au>

"Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:

> Machine Code:
> Whatever the machine executes, it could be that the CPU uses an
> abstraction of microcode to do this but from the perspective of the
> user, this is all done in the same 'black box'

This requires, of course, defining what is the machine. Python bytecode
targets a virtual machine that is implemented differently for each
hardware platform.

> Compiling:
> Translate words/symbols/mnemonics to machine code, which than can be
> either loaded, linked and executed by an OS or read and executed by
> the BIOS.

Related to the above point, the ?machine code? can just as easily be
codes for a virtual machine specification. This is the case for the
bytecode instructions Python gets compiled to.

> Interpreted:
> Instructions which can be fed to a previous compiled program that is
> able to dynamically change its execution and flow without the need to
> recompile itself.

This doesn't make much sense to me, I must say.

I'd say, instead, that a program is interpreted if its instruction are
dynamically translated to underlying platform instructions at execution
time. This is the case for the bytecode instructions interpreted by the
Python virtual machine.

-- 
 \      ?Often, the surest way to convey misinformation is to tell the |
  `\               strict truth.? ?Mark Twain, _Following the Equator_ |
_o__)                                                                  |
Ben Finney


From invalid at invalid  Thu Jul 30 10:55:26 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 09:55:26 -0500
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
Message-ID: <tJWdnXvaWJnDKezXnZ2dnUVZ_jdi4p2d@posted.visi>

On 2009-07-30, Martin P. Hellwig <martin.hellwig at dcuktec.org> wrote:
> Michel Claveau - MVP wrote:
>
>>> Python is interpreted
>> 
>> No. Python is compiled (--> .pyc)
>> But the term "to compile" is not always unambiguous...
>> And the notion of "compiler" is not attached to Python (the
>> language), but is attached to the implementation.
>
> Well the pyc, which I thought was the Python bytecode,

It is, but that's just one particular implementation you're
talking about (though by far the most widely used one).

> is then interpreted by the VM.

Yup.  Just like .exe files are interpreted by the microcode in
the processor that implements the IA32 VM.  It would be quite
possible to put a Python VM into hardware.  Alternatevly, you
can compiler Python into Java bytecode and run that "directly"
on hardware.

-- 
Grant Edwards                   grante             Yow! It don't mean a
                                  at               THING if you ain't got
                               visi.com            that SWING!!


From draghuram at gmail.com  Thu Jul 30 10:59:40 2009
From: draghuram at gmail.com (Raghuram Devarakonda)
Date: Thu, 30 Jul 2009 07:59:40 -0700 (PDT)
Subject: Connecting multiple test cases in a sort of pipe
References: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>
	<7dctogF29q4c6U1@mid.uni-berlin.de>
Message-ID: <63715814-ff14-4b95-9160-d98325640a8b@v20g2000yqm.googlegroups.com>

On Jul 30, 2:43 am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Write a TestCase-subclass that simply works like this:
>
> class FileTests(TestCase):
>
>     def test_create(self):
>         self.created_file = create()
>         assert something
>
>     def test_list(self):
>         self.test_create()
>         delete(self.created_file)
>
> Passing state around is one of the reasons objects have been invented :)
> And nobody ever said that you can't invoke a test-method from somewhere
> else.

Just to be clear, are you suggesting that these tests be run by a
custom runnner rather than by the default runner from unittest?

Thanks,
Raghu


From invalid at invalid  Thu Jul 30 11:03:56 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 10:03:56 -0500
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
Message-ID: <arCdnYGeC-LBK-zXnZ2dnUVZ_qidnZ2d@posted.visi>

On 2009-07-30, Dave Angel <davea at ieee.org> wrote:

> As far as I know, nobody has yet built a microcode implementation of a 
> Python VM (Virtual Machine).  Nor have I seen one for the Java VM.  

Didn't Sun or somebody do one 10-12 years ago?  Or did I
misinterpret some press release or something?  Off to google...

> However, in the early 80's there was a microcode implementation of the
> P-system VM.

Ah yes.  I remember sitting at an Intel MDS-80 "blue box" CP/M
system entering assembly language by hand for a simple Pascal
-> P-code compiler.  IIRC, I typed it from a listing in the
"Byte Big Book of Pascal".  That machine was pretty high-tech,
since I could save my work on an 8" floppy rather than a spool
of paper tape.  The floppy disks didn't leave big oil stains in
your backpack!

I got the compiler working, but I don't remember ever having a
VM and run-time system.

> It was never a commercial success, but it existed.  And there
> have been at least three Forth machines, where the hardware
> itself was designed to support the language's VM.  No
> microcode at all.

-- 
Grant Edwards                   grante             Yow! When you get your
                                  at               PH.D. will you get able to
                               visi.com            work at BURGER KING?


From keith at nekotaku.com  Thu Jul 30 11:09:20 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 08:09:20 -0700 (PDT)
Subject: Use existing IE cookie
Message-ID: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>

Hi there,

Relevant versions: Python 2.5, Vista Home, IE7

I am trying to scrape a website I have browsed manually in the past,
and also manually selected my options, and now want python to use my
existing cookie from the manual browse when downloading data.

Using: http://code.activestate.com/recipes/80443/ I have found the
"name" of the relevant cookie, just after reading urllib2 docs, I
can't see how to "send" or have my python instance use "MY" existing
cookie.

Using the following:

***
import re
import urllib2, cookielib

# set things up for cookies

opener = urllib2.build_opener(urllib2.HTTPCookieProcessor())
urllib2.install_opener(opener)

reply = urllib2.urlopen('foo.html').read()

print reply

***

This does return data, just default data, not the data from the
options I set up when manually browsing.

My sense is that I need "something" in the () part of
HTTPCookieProcessor() but I have no idea as to what... the docs say
"cookiejar" but the only code examples I have found are to create a
cookiejar for the existing Python session, not to use the cookies from
my prior manual meanderings.

Any help greatly appreciated.


From Ron.Barak at lsi.com  Thu Jul 30 11:10:17 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 16:10:17 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <4A7199FF.8010202@dejaviewphoto.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26D2@enbmail01.lsi.com>

Hi Dave,

On second thoughts, I may have a problem implementing the wrapper solution, because my actual test_pyc.pyc, needs to parse its command line.
Namely, the actual call to test_pyc.pyc looks something like this:

$ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t tvn -p pool1 -l -c

And I don't know of a way to add these parameters to the "import  test_pyc" in wrapper

Is there a way to pass information to an imported module ? (Sorry if there's an obvious answer, I just cannot figure it out).

Bye,
Ron.

> -----Original Message-----
> From: Dave Angel [mailto:davea at dejaviewphoto.com] 
> Sent: Thursday, July 30, 2009 16:03
> To: Barak, Ron
> Cc: 'Dave Angel'; 'python-list at python.org'
> Subject: RE: Run pyc file without specifying python path ?
> 
> Barak, Ron wrote:
> >> -----Original Message-----
> >> From: Dave Angel [mailto:davea at ieee.org]
> >> Sent: Wednesday, July 29, 2009 21:05
> >> To: Barak, Ron
> >> Cc: 'python-list at python.org'
> >> Subject: Re: Run pyc file without specifying python path ?
> >>
> >> Barak, Ron wrote:
> >>     
> >>> Hi,
> >>>
> >>> I wanted to make a python byte-code file executable,
> >>>       
> >> expecting to be able to run it without specifying "python" on the 
> >> (Linux bash) command line.
> >>     
> >>> So, I wrote the following:
> >>>
> >>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
> >>>
> >>> print "hello"
> >>> [root at VMLinux1 python]#
> >>>
> >>> and made its pyc file executable:
> >>>
> >>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> >>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> >>> [root at VMLinux1 python]#
> >>>
> >>> So, I see:
> >>>
> >>> [root at VMLinux1 python]# file test_pyc.py*
> >>> test_pyc.py:  a python script text executable
> >>> test_pyc.pyc: python 2.3 byte-compiled
> >>> [root at VMLinux1 python]#
> >>>
> >>> If I try to do the following, no problem:
> >>>
> >>> [root at VMLinux1 python]# python test_pyc.pyc hello
> >>> [root at VMLinux1 python]#
> >>>
> >>> However, the following fails:
> >>>
> >>> [root at VMLinux1 python]# ./test_pyc.pyc
> >>> -bash: ./test_pyc.pyc: cannot execute binary file
> >>> [root at VMLinux1 python]#
> >>>
> >>> Is there a way to run a pyc file without specifying the
> >>>       
> >> python path ?
> >>     
> >>> Bye,
> >>> Ron.
> >>>
> >>>   
> >>>       
> >> I don't currently run Unix, but I think I know the problem.
> >>
> >> In a text file, the shell examines the first line, and if 
> it begins 
> >> #!
> >> it's assumed to point to the executable of an interpreter for that 
> >> text file.  Presumably the same trick doesn't work for a .pyc file.
> >>
> >> Why not write a trivial wrapper.py file, don't compile it, and let 
> >> that invoke the main code in the .pyc file?
> >>
> >> Then make wrapper.py executable, and you're ready to go.
> >>
> >> DaveA
> >>
> >>
> >>     
> >
> > Hi Dave,
> > Your solution sort of defeats my intended purpose (sorry 
> for not divulging my 'hidden agenda').
> > I wanted my application to "hide" the fact that it's a 
> python script, and look as much as possible like it's a 
> compiled program.
> > The reason I don't just give my user a py file, is that I 
> don't want a cleaver user to change the innards of the script.
> > On the other hand, I don't want to make a compiled 
> (freezed?) version of the application, because it'll grow the 
> resulting file significantly, and I don't have the experience 
> to know how it will run on different Linuxes.
> > Bye,
> > Ron. 
> >   
> Most of the other answers basically paraphrased my suggestion 
> of making a wrapper file, not compiling it, and making it 
> executable.  With that 
> approach, the user just types   "wrapper.py" on his command line.
> 
> And wrapper.py only needs two lines, a shebang, and an 
> import, no big deal if the user modifies it.  The rest of 
> your code can be .pyc files.
> 
> Steven makes some good points.  You have to define what level 
> of clever you're protecting from.  A determined hacker will 
> get in no matter what you do, unless you want to ship the 
> program in a proprietary embedded system, encased in epoxy.  
> Further, if you have an extension of .py or .pyc, a 
> knowledgeable hacker will know it's probably python.
> 
> You imply you want it to run unmodifed on multiple unknown 
> Linux versions.  I think that lets out binfmt solutions.  
> That means you need to test and support not only multiple 
> Linux implementations, but multiple Python versions, because 
> who knows what the user may have installed.  I think you need 
> to rethink your support strategy.  And maybe concentrate on 
> being able to detect change, rather than prevent it.
> 
> DaveA
> 
> 
> 

From deets at nospam.web.de  Thu Jul 30 11:16:44 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 17:16:44 +0200
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
Message-ID: <7ddrqsF2b5mblU1@mid.uni-berlin.de>

KB wrote:

> Hi there,
> 
> Relevant versions: Python 2.5, Vista Home, IE7
> 
> I am trying to scrape a website I have browsed manually in the past,
> and also manually selected my options, and now want python to use my
> existing cookie from the manual browse when downloading data.
> 
> Using: http://code.activestate.com/recipes/80443/ I have found the
> "name" of the relevant cookie, just after reading urllib2 docs, I
> can't see how to "send" or have my python instance use "MY" existing
> cookie.
> 
> Using the following:
> 
> ***
> import re
> import urllib2, cookielib
> 
> # set things up for cookies
> 
> opener = urllib2.build_opener(urllib2.HTTPCookieProcessor())
> urllib2.install_opener(opener)
> 
> reply = urllib2.urlopen('foo.html').read()
> 
> print reply
> 
> ***
> 
> This does return data, just default data, not the data from the
> options I set up when manually browsing.
> 
> My sense is that I need "something" in the () part of
> HTTPCookieProcessor() but I have no idea as to what... the docs say
> "cookiejar" but the only code examples I have found are to create a
> cookiejar for the existing Python session, not to use the cookies from
> my prior manual meanderings.

Because this is a completely different beast. You need to find out if and
how to access IE-cookies from python - I guess some win32-road is to be
walked down for that.

Once you get a hold on them, you can build up whatever cookiejar urllib2
needs.

Diez


From invalid at invalid  Thu Jul 30 11:16:46 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 10:16:46 -0500
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
	<mailman.3970.1248966648.8015.python-list@python.org>
Message-ID: <27mdnb-NxM3DJOzXnZ2dnUVZ_hxi4p2d@posted.visi>

On 2009-07-30, Barak, Ron <Ron.Barak at lsi.com> wrote:
> Hi Dave,
>
> On second thoughts, I may have a problem implementing the
> wrapper solution, because my actual test_pyc.pyc, needs to
> parse its command line. Namely, the actual call to
> test_pyc.pyc looks something like this:
>
> $ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t tvn -p pool1 -l -c
>
> And I don't know of a way to add these parameters to the
> "import test_pyc" in wrapper
>
> Is there a way to pass information to an imported module ?
> (Sorry if there's an obvious answer, I just cannot figure it
> out).

I don't understand your problem.  The module would parse
sys.argv just like always.

If you don't like that for some reason, you could define an
entry point in the module and call it:

#!/usr/bin/python
import sys,test_pyc
test_pyc.main(*sys.argv)

-- 
Grant Edwards                   grante             Yow! We just joined the
                                  at               civil hair patrol!
                               visi.com            


From keith at nekotaku.com  Thu Jul 30 11:19:08 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 08:19:08 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
Message-ID: <3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>


> > Using:http://code.activestate.com/recipes/80443/
>

Thanks for the prompt reply, Diez! Using the above I have found the
name of the cookie (I did google how to use IE cookies in python and
that was the best match) but it only tells me the name of the cookie,
not how to use it.

Any clues?

TIA!


From dkatkowski at gmail.com  Thu Jul 30 11:25:58 2009
From: dkatkowski at gmail.com (Feyo)
Date: Thu, 30 Jul 2009 08:25:58 -0700 (PDT)
Subject: Help with Regex for domain names
Message-ID: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>

I'm trying to figure out how to write efficiently write a regex for
domain names with a particular top level domain. Let's say, I want to
grab all domain names with country codes .us, .au, and .de.

I could create three different regexs that would work:
regex = re.compile(r'[\w\-\.]+\.us)
regex = re.compile(r'[\w\-\.]+\.au)
regex = re.compile(r'[\w\-\.]+\.de)

How would I write one to accommodate all three, or, better yet, to
accommodate a list of them that I can pass into a method call? Thanks!


From martin.hellwig at dcuktec.org  Thu Jul 30 11:41:56 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 16:41:56 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <87vdlate6o.fsf@benfinney.id.au>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
	<87vdlate6o.fsf@benfinney.id.au>
Message-ID: <M-udnUIs853YIuzXnZ2dnUVZ8radnZ2d@bt.com>

Ben Finney wrote:
> "Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:
> 
>> Machine Code:
>> Whatever the machine executes, it could be that the CPU uses an
>> abstraction of microcode to do this but from the perspective of the
>> user, this is all done in the same 'black box'
> 
> This requires, of course, defining what is the machine. Python bytecode
> targets a virtual machine that is implemented differently for each
> hardware platform.
> 

I would further define 'black box' as the hardware a kernel programmer 
writes to.

<cut>

>> Interpreted:
>> Instructions which can be fed to a previous compiled program that is
>> able to dynamically change its execution and flow without the need to
>> recompile itself.
> 
> This doesn't make much sense to me, I must say.
> 
> I'd say, instead, that a program is interpreted if its instruction are
> dynamically translated to underlying platform instructions at execution
> time. This is the case for the bytecode instructions interpreted by the
> Python virtual machine.
> 

Yes that is indeed a much better description, I'll steal that from you :-)

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From deets at nospam.web.de  Thu Jul 30 11:43:31 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 17:43:31 +0200
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
Message-ID: <7ddtd3F297bafU1@mid.uni-berlin.de>

KB wrote:

> 
>> > Using:http://code.activestate.com/recipes/80443/
>>
> 
> Thanks for the prompt reply, Diez! Using the above I have found the
> name of the cookie (I did google how to use IE cookies in python and
> that was the best match) but it only tells me the name of the cookie,
> not how to use it.

Ah, sorry, should have read the recipe also. 

For me it looks as if findIECookie from that recipe is to be called with the
name. Then it should return the value, or None

What does you full example look like, including the
cookie-acquisition-stuff?

Diez


From tundra at tundraware.com  Thu Jul 30 11:47:06 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Thu, 30 Jul 2009 10:47:06 -0500
Subject: Help with Regex for domain names
In-Reply-To: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
Message-ID: <msr8k6-dai1.ln1@ozzie.tundraware.com>

Feyo wrote:
> I'm trying to figure out how to write efficiently write a regex for
> domain names with a particular top level domain. Let's say, I want to
> grab all domain names with country codes .us, .au, and .de.
> 
> I could create three different regexs that would work:
> regex = re.compile(r'[\w\-\.]+\.us)
> regex = re.compile(r'[\w\-\.]+\.au)
> regex = re.compile(r'[\w\-\.]+\.de)
> 
> How would I write one to accommodate all three, or, better yet, to
> accommodate a list of them that I can pass into a method call? Thanks!

Just a point of interest:  A correctly formed domain name may have a
trailing period at the end of the TLD [1].  Example:

       foo.bar.com.

Though you do not often see this, it's worth accommodating "just in
case"...


[1] http://homepages.tesco.net/J.deBoynePollard/FGA/web-fully-qualified-domain-name.html



-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From python at mrabarnett.plus.com  Thu Jul 30 11:50:37 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 16:50:37 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <4A719E2D.708@ieee.org>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<4A719E2D.708@ieee.org>
Message-ID: <4A71C14D.7030805@mrabarnett.plus.com>

Dave Angel wrote:
[snip]
> As far as I know, nobody has yet built a microcode implementation of a 
> Python VM (Virtual Machine).  Nor have I seen one for the Java VM.  
> However, in the early 80's there was a microcode implementation of the 
> P-system VM.  It was never a commercial success, but it existed.  And 
> there have been at least three Forth machines, where the hardware itself 
> was designed to support the language's VM.  No microcode at all.
> 
There's Jazelle: http://en.wikipedia.org/wiki/Jazelle.


From python at mrabarnett.plus.com  Thu Jul 30 11:53:35 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 16:53:35 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <87vdlate6o.fsf@benfinney.id.au>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>	<mailman.3963.1248960056.8015.python-list@python.org>	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
	<87vdlate6o.fsf@benfinney.id.au>
Message-ID: <4A71C1FF.2070702@mrabarnett.plus.com>

Ben Finney wrote:
> "Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:
> 
>> Machine Code:
>> Whatever the machine executes, it could be that the CPU uses an
>> abstraction of microcode to do this but from the perspective of the
>> user, this is all done in the same 'black box'
> 
> This requires, of course, defining what is the machine. Python bytecode
> targets a virtual machine that is implemented differently for each
> hardware platform.
> 
>> Compiling:
>> Translate words/symbols/mnemonics to machine code, which than can be
>> either loaded, linked and executed by an OS or read and executed by
>> the BIOS.
> 
> Related to the above point, the ?machine code? can just as easily be
> codes for a virtual machine specification. This is the case for the
> bytecode instructions Python gets compiled to.
> 
>> Interpreted:
>> Instructions which can be fed to a previous compiled program that is
>> able to dynamically change its execution and flow without the need to
>> recompile itself.
> 
> This doesn't make much sense to me, I must say.
> 
> I'd say, instead, that a program is interpreted if its instruction are
> dynamically translated to underlying platform instructions at execution
> time. This is the case for the bytecode instructions interpreted by the
> Python virtual machine.
> 
Interpretation doesn't necessarily mean translating to machine code at
execution time. What you're describing is more like JIT.


From python at mrabarnett.plus.com  Thu Jul 30 11:56:23 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 16:56:23 +0100
Subject: Help with Regex for domain names
In-Reply-To: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
Message-ID: <4A71C2A7.90900@mrabarnett.plus.com>

Feyo wrote:
> I'm trying to figure out how to write efficiently write a regex for
> domain names with a particular top level domain. Let's say, I want to
> grab all domain names with country codes .us, .au, and .de.
> 
> I could create three different regexs that would work:
> regex = re.compile(r'[\w\-\.]+\.us)
> regex = re.compile(r'[\w\-\.]+\.au)
> regex = re.compile(r'[\w\-\.]+\.de)
> 
> How would I write one to accommodate all three, or, better yet, to
> accommodate a list of them that I can pass into a method call? Thanks!
 >
regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')

If you have a list of country codes ["us", "au", "de"] then you can
build the regular expression from it:

regex = re.compile(r'[\w\-\.]+\.(?:%s)' % '|'.join(domains))


From keith at nekotaku.com  Thu Jul 30 11:58:56 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 08:58:56 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
Message-ID: <22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>


> What does you full example look like, including the
> cookie-acquisition-stuff?
>
> Diez

I ran them seperately, hoping for a clue as to what my "cookiejar"
was.

The cookie-acquisition stuff returns "screener.ashx?v=151" when I
search with my domain I am interested in. I have tried
urllib2.HTTPCookieProcessor('screener.ashx?v=151') but that failed
with attr has no cookie header.

>From the HTTPCookieProcessor doco, it appears that non-IE browsers
have a cookie file (and example code) but from what I can tell IE uses
a hidden folder. (you can set your location in IE but it appends a
folder "\Temporary Internet Files"  -

From: http://docs.python.org/dev/library/cookielib.html

***
This example illustrates how to open a URL using your Netscape,
Mozilla, or Lynx cookies (assumes Unix/Netscape convention for
location of the cookies file):

import os, cookielib, urllib2
cj = cookielib.MozillaCookieJar()
cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
r = opener.open("http://example.com/")
***

Not sure how to adapt this for IE.


From darkneter at gmail.com  Thu Jul 30 12:06:11 2009
From: darkneter at gmail.com (NighterNet)
Date: Thu, 30 Jul 2009 09:06:11 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<mailman.3966.1248962186.8015.python-list@python.org>
Message-ID: <15017646-6e20-40ff-af70-5717598f26bb@a39g2000pre.googlegroups.com>

On Jul 30, 6:56?am, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
> "NighterNet" <darkne... at gmail.com> wrote in message
>
> news:55aba832-df6d-455f-bf34-04d37eb061cd at i4g2000prm.googlegroups.com...
>
> >I am trying to figure out how to send text or byte in python3.1. I am
> > trying to send data to flashsocketto get there. I am not sure how to
> > work it.
>
> > buff= 'id=' , self.id , ':balive=False\n'
> > clientSock.send(buff);
> > --
> >http://mail.python.org/mailman/listinfo/python-list
>
> Python3.1strings are Unicode (think characters not bytes). ?When writing
> to files, sockets, etc. bytes must be used. ?Unicode strings have an
> encode() method, where you can specify an appropriate encoding (ascii,
> latin-1, windows-1252, utf-8, etc.):
>
> ? ? clientSock.send(buff.encode('ascii'))
>
> When reading from thesocket, you can decode() the byte strings back into
> Unicode strings.
>
> ? ? data = clientSock.recv(1024).decode('ascii')
>
> -Mark

I am not sure how to use struct package.
Here an example for the input:
{id:1,playername:guest,x:100,y:50}
{id:2,playername:tester,x:100,y:50}

struct.pack(? )


From cjw at ncf.ca  Thu Jul 30 12:18:07 2009
From: cjw at ncf.ca (Colin J. Williams)
Date: Thu, 30 Jul 2009 12:18:07 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <h4sh41$fu7$1@theodyn.ncf.ca>

Some have treated this as a troll.  I don't.
r wrote:
[snip]

> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.
> 
+1
> 2.) the .each method
> container.each{|localVar| block}
> This method can really cleanup some ugly for loops, although i really
> like the readability of for loops.
> 
Not clear.
> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max(). You know what i am talking about here people. We
> all get complacent and It seems easier to just cope with these
> problems instead of fighting for change. But look at the French,  WHAT
> THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!
> 
+0.6
or better [1, 2, 3, 4, 5].len or [1, 2, 3, 4, 5].max

What has this got to do with "true OOP"?

[snip]


From deets at nospam.web.de  Thu Jul 30 12:23:59 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 18:23:59 +0200
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
Message-ID: <7ddvp0F2brmgrU1@mid.uni-berlin.de>

KB wrote:

> 
>> What does you full example look like, including the
>> cookie-acquisition-stuff?
>>
>> Diez
> 
> I ran them seperately, hoping for a clue as to what my "cookiejar"
> was.
> 
> The cookie-acquisition stuff returns "screener.ashx?v=151" when I
> search with my domain I am interested in. I have tried
> urllib2.HTTPCookieProcessor('screener.ashx?v=151') but that failed
> with attr has no cookie header.
> 
> From the HTTPCookieProcessor doco, it appears that non-IE browsers
> have a cookie file (and example code) but from what I can tell IE uses
> a hidden folder. (you can set your location in IE but it appends a
> folder "\Temporary Internet Files"  -
> 
> From: http://docs.python.org/dev/library/cookielib.html
> 
> ***
> This example illustrates how to open a URL using your Netscape,
> Mozilla, or Lynx cookies (assumes Unix/Netscape convention for
> location of the cookies file):
> 
> import os, cookielib, urllib2
> cj = cookielib.MozillaCookieJar()
> cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
> opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
> r = opener.open("http://example.com/")
> ***
> 
> Not sure how to adapt this for IE.

You could create a file that resembles the cookies.txt - no idea how that
looks, but I guess it's pretty simple. 

Diez


From ethan at stoneleaf.us  Thu Jul 30 12:27:32 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 30 Jul 2009 09:27:32 -0700
Subject: Does python have the capability for driver development ?
In-Reply-To: <87vdlate6o.fsf@benfinney.id.au>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>	<mailman.3963.1248960056.8015.python-list@python.org>	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
	<87vdlate6o.fsf@benfinney.id.au>
Message-ID: <4A71C9F4.8040006@stoneleaf.us>

Ben Finney wrote:
> "Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:
> 
> 
>>Machine Code:
>>Whatever the machine executes, it could be that the CPU uses an
>>abstraction of microcode to do this but from the perspective of the
>>user, this is all done in the same 'black box'
> 
> 
> This requires, of course, defining what is the machine. Python bytecode
> targets a virtual machine that is implemented differently for each
> hardware platform.
> 
> 
>>Compiling:
>>Translate words/symbols/mnemonics to machine code, which than can be
>>either loaded, linked and executed by an OS or read and executed by
>>the BIOS.
> 
> 
> Related to the above point, the ?machine code? can just as easily be
> codes for a virtual machine specification. This is the case for the
> bytecode instructions Python gets compiled to.
> 
> 
>>Interpreted:
>>Instructions which can be fed to a previous compiled program that is
>>able to dynamically change its execution and flow without the need to
>>recompile itself.
> 
> 
> This doesn't make much sense to me, I must say.
> 
> I'd say, instead, that a program is interpreted if its instruction are
> dynamically translated to underlying platform instructions at execution
> time. This is the case for the bytecode instructions interpreted by the
> Python virtual machine.
> 

I would have said compiled is executed by hardware, interpreted is 
executed by software -- but I like your definition better.  :)

~Ethan~


From garrickp at gmail.com  Thu Jul 30 12:31:22 2009
From: garrickp at gmail.com (Falcolas)
Date: Thu, 30 Jul 2009 09:31:22 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>

On Jul 29, 9:06?pm, r <rt8... at gmail.com> wrote:

> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.

I personally would not prefer this, and would likely continue to use
(), precisely for code clarity - let me explain:

foo.nextval
foo.val
foo.previousval

Which of the calls above referenced instance variables, and which ones
called functions which changed the internal state of foo? I would have
trouble saying, just based on the calls above. I would have to go back
to the definition or documentation of foo to identify which is doing
what. On the other hand, the following gives a better clue as to what
is happening (granted not perfect, but better):

foo.nextval()
foo.val
foo.previousval()

~G


From keith at nekotaku.com  Thu Jul 30 12:31:33 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 09:31:33 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
	<7ddvp0F2brmgrU1@mid.uni-berlin.de>
Message-ID: <33b7685b-054a-442c-8e97-46a5b77f7900@z4g2000prh.googlegroups.com>

On Jul 30, 9:23?am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> KB wrote:
>
> >> What does you full example look like, including the
> >> cookie-acquisition-stuff?
>
> >> Diez
>
> > I ran them seperately, hoping for a clue as to what my "cookiejar"
> > was.
>
> > The cookie-acquisition stuff returns "screener.ashx?v=151" when I
> > search with my domain I am interested in. I have tried
> > urllib2.HTTPCookieProcessor('screener.ashx?v=151') but that failed
> > with attr has no cookie header.
>
> > From the HTTPCookieProcessor doco, it appears that non-IE browsers
> > have a cookie file (and example code) but from what I can tell IE uses
> > a hidden folder. (you can set your location in IE but it appends a
> > folder "\Temporary Internet Files" ?-
>
> > From:http://docs.python.org/dev/library/cookielib.html
>
> > ***
> > This example illustrates how to open a URL using your Netscape,
> > Mozilla, or Lynx cookies (assumes Unix/Netscape convention for
> > location of the cookies file):
>
> > import os, cookielib, urllib2
> > cj = cookielib.MozillaCookieJar()
> > cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
> > opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
> > r = opener.open("http://example.com/")
> > ***
>
> > Not sure how to adapt this for IE.
>
> You could create a file that resembles the cookies.txt - no idea how that
> looks, but I guess it's pretty simple.
>
> Diez- Hide quoted text -
>
> - Show quoted text -

Yeah unfortunately I just tried Firefox and it uses cookies.sqlite
now... more dead ends :)


From edreamleo at charter.net  Thu Jul 30 12:45:32 2009
From: edreamleo at charter.net (Edward K Ream)
Date: Thu, 30 Jul 2009 11:45:32 -0500
Subject: ANN: Leo 4.6.1 final released
Message-ID: <e8kcm.21745$yP1.19646@newsfe01.iad>

Leo 4.6.1 final is now available at:
http://sourceforge.net/project/showfiles.php?group_id=3458&package_id=29106

Leo is a text editor, data organizer, project manager and much more. See:
http://webpages.charter.net/edreamleo/intro.html

Leo 4.6.1 fixes several minor bugs in Leo 4.6.

The highlights of Leo 4.6
--------------------------
- Cached external files *greatly* reduces the time to load .leo files.
- Leo now features a modern Qt interface by default.
  Leo's legacy Tk interface can also be used.
- New --config, --file and --gui command-line options.
- Leo tests syntax of .py files when saving them.
- Leo can now open any kind of file into @edit nodes.
- @auto-rst nodes allow easy editing of reStructuredText files.
- Properties of commanders, positions and nodes simplify programming.
- Improved Leo's unit testing framework.
- Leo now requires Python 2.5 or later.
- Dozens of small improvements and bug fixes.

Links:
------
Leo:      http://webpages.charter.net/edreamleo/front.html
Forum:    http://groups.google.com/group/leo-editor
Download: http://sourceforge.net/project/showfiles.php?group_id=3458
Bzr:      http://code.launchpad.net/leo-editor/
Quotes:   http://webpages.charter.net/edreamleo/testimonials.html
--------------------------------------------------------------------
Edward K. Ream   email:  edreamleo at yahoo.com
Leo: http://webpages.charter.net/edreamleo/front.html
--------------------------------------------------------------------




From inky788 at gmail.com  Thu Jul 30 13:01:40 2009
From: inky788 at gmail.com (Inky 788)
Date: Thu, 30 Jul 2009 10:01:40 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>

On Jul 30, 12:04?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
>
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?

I agree with alex here. Will take the explicit syntax over the extra
cognitive load of figuring out exactly what's going on with
`obj.m1.m2.m3`.

Python has its warts, but requiring ()'s on function calls isn't one
of them. :)


From bieffe62 at gmail.com  Thu Jul 30 13:03:42 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 10:03:42 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<mailman.3966.1248962186.8015.python-list@python.org>
	<15017646-6e20-40ff-af70-5717598f26bb@a39g2000pre.googlegroups.com>
Message-ID: <3b14ad80-2e0e-4d4f-92e7-684dc75a7a05@w41g2000yqb.googlegroups.com>

On 30 Lug, 18:06, NighterNet <darkne... at gmail.com> wrote:
> On Jul 30, 6:56?am, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
>
>
>
>
>
> > "NighterNet" <darkne... at gmail.com> wrote in message
>
> >news:55aba832-df6d-455f-bf34-04d37eb061cd at i4g2000prm.googlegroups.com...
>
> > >I am trying to figure out how to send text or byte in python3.1. I am
> > > trying to send data to flashsocketto get there. I am not sure how to
> > > work it.
>
> > > buff= 'id=' , self.id , ':balive=False\n'
> > > clientSock.send(buff);
> > > --
> > >http://mail.python.org/mailman/listinfo/python-list
>
> > Python3.1strings are Unicode (think characters not bytes). ?When writing
> > to files, sockets, etc. bytes must be used. ?Unicode strings have an
> > encode() method, where you can specify an appropriate encoding (ascii,
> > latin-1, windows-1252, utf-8, etc.):
>
> > ? ? clientSock.send(buff.encode('ascii'))
>
> > When reading from thesocket, you can decode() the byte strings back into
> > Unicode strings.
>
> > ? ? data = clientSock.recv(1024).decode('ascii')
>
> > -Mark
>
> I am not sure how to use struct package.
> Here an example for the input:
> {id:1,playername:guest,x:100,y:50}
> {id:2,playername:tester,x:100,y:50}
>
> struct.pack(? )

If your messages are ASCII, like it seems, forget about struct, which
is for 'binary' message format.
Format the string as you would in 2.6 ( using % or string.format for
instance ) and then use encode
as instructed.




From davea at dejaviewphoto.com  Thu Jul 30 13:07:43 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Thu, 30 Jul 2009 13:07:43 -0400
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26D2@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26D2@enbmail01.lsi.com>
Message-ID: <4A71D35F.3090800@dejaviewphoto.com>

Barak, Ron wrote:
> Hi Dave,
>
> On second thoughts, I may have a problem implementing the wrapper solution, because my actual test_pyc.pyc, needs to parse its command line.
> Namely, the actual call to test_pyc.pyc looks something like this:
>
> $ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t tvn -p pool1 -l -c
>
> And I don't know of a way to add these parameters to the "import  test_pyc" in wrapper
>
> Is there a way to pass information to an imported module ? (Sorry if there's an obvious answer, I just cannot figure it out).
>
> Bye,
> Ron.
>
>   
>> -----Original Message-----
>> From: Dave Angel [mailto:davea at dejaviewphoto.com] 
>> Sent: Thursday, July 30, 2009 16:03
>> To: Barak, Ron
>> Cc: 'Dave Angel'; 'python-list at python.org'
>> Subject: RE: Run pyc file without specifying python path ?
>>
>> Barak, Ron wrote:
>>     
>>>> -----Original Message-----
>>>> From: Dave Angel [mailto:davea at ieee.org]
>>>> Sent: Wednesday, July 29, 2009 21:05
>>>> To: Barak, Ron
>>>> Cc: 'python-list at python.org'
>>>> Subject: Re: Run pyc file without specifying python path ?
>>>>
>>>> Barak, Ron wrote:
>>>>     
>>>>         
>>>>> Hi,
>>>>>
>>>>> I wanted to make a python byte-code file executable,
>>>>>       
>>>>>           
>>>> expecting to be able to run it without specifying "python" on the 
>>>> (Linux bash) command line.
>>>>     
>>>>         
>>>>> So, I wrote the following:
>>>>>
>>>>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
>>>>>
>>>>> print "hello"
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> and made its pyc file executable:
>>>>>
>>>>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
>>>>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> So, I see:
>>>>>
>>>>> [root at VMLinux1 python]# file test_pyc.py*
>>>>> test_pyc.py:  a python script text executable
>>>>> test_pyc.pyc: python 2.3 byte-compiled
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> If I try to do the following, no problem:
>>>>>
>>>>> [root at VMLinux1 python]# python test_pyc.pyc hello
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> However, the following fails:
>>>>>
>>>>> [root at VMLinux1 python]# ./test_pyc.pyc
>>>>> -bash: ./test_pyc.pyc: cannot execute binary file
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> Is there a way to run a pyc file without specifying the
>>>>>       
>>>>>           
>>>> python path ?
>>>>     
>>>>         
>>>>> Bye,
>>>>> Ron.
>>>>>
>>>>>   
>>>>>       
>>>>>           
>>>> I don't currently run Unix, but I think I know the problem.
>>>>
>>>> In a text file, the shell examines the first line, and if 
>>>>         
>> it begins 
>>     
>>>> #!
>>>> it's assumed to point to the executable of an interpreter for that 
>>>> text file.  Presumably the same trick doesn't work for a .pyc file.
>>>>
>>>> Why not write a trivial wrapper.py file, don't compile it, and let 
>>>> that invoke the main code in the .pyc file?
>>>>
>>>> Then make wrapper.py executable, and you're ready to go.
>>>>
>>>> DaveA
>>>>
>>>>
>>>>     
>>>>         
>>> Hi Dave,
>>> Your solution sort of defeats my intended purpose (sorry 
>>>       
>> for not divulging my 'hidden agenda').
>>     
>>> I wanted my application to "hide" the fact that it's a 
>>>       
>> python script, and look as much as possible like it's a 
>> compiled program.
>>     
>>> The reason I don't just give my user a py file, is that I 
>>>       
>> don't want a cleaver user to change the innards of the script.
>>     
>>> On the other hand, I don't want to make a compiled 
>>>       
>> (freezed?) version of the application, because it'll grow the 
>> resulting file significantly, and I don't have the experience 
>> to know how it will run on different Linuxes.
>>     
>>> Bye,
>>> Ron. 
>>>   
>>>       
>> Most of the other answers basically paraphrased my suggestion 
>> of making a wrapper file, not compiling it, and making it 
>> executable.  With that 
>> approach, the user just types   "wrapper.py" on his command line.
>>
>> And wrapper.py only needs two lines, a shebang, and an 
>> import, no big deal if the user modifies it.  The rest of 
>> your code can be .pyc files.
>>
>> Steven makes some good points.  You have to define what level 
>> of clever you're protecting from.  A determined hacker will 
>> get in no matter what you do, unless you want to ship the 
>> program in a proprietary embedded system, encased in epoxy.  
>> Further, if you have an extension of .py or .pyc, a 
>> knowledgeable hacker will know it's probably python.
>>
>> You imply you want it to run unmodifed on multiple unknown 
>> Linux versions.  I think that lets out binfmt solutions.  
>> That means you need to test and support not only multiple 
>> Linux implementations, but multiple Python versions, because 
>> who knows what the user may have installed.  I think you need 
>> to rethink your support strategy.  And maybe concentrate on 
>> being able to detect change, rather than prevent it.
>>
>> DaveA
>>
>>
>>
>>     
(Please don't top-post.  It puts responses out of order)

You don't have to do anything special.  Any module can import sys, and 
parse sys.argv, as long as it wasn't yet modified.

DaveA


From rt8396 at gmail.com  Thu Jul 30 13:09:02 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:09:02 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
Message-ID: <a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>

On Jul 30, 11:31?am, Falcolas <garri... at gmail.com> wrote:
> On Jul 29, 9:06?pm, r <rt8... at gmail.com> wrote:
>
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> I personally would not prefer this, and would likely continue to use
> (), precisely for code clarity - let me explain:
>
> foo.nextval
> foo.val
> foo.previousval
>
> Which of the calls above referenced instance variables, and which ones
> called functions which changed the internal state of foo? I would have
> trouble saying, just based on the calls above. I would have to go back
> to the definition or documentation of foo to identify which is doing
> what. On the other hand, the following gives a better clue as to what
> is happening (granted not perfect, but better):
>
> foo.nextval()
> foo.val
> foo.previousval()
>
> ~G

I held your exact same view before i learned the Ruby language. And
your veiw makes some good points, however, naming conventions with
eliminate this problem all together. All "method names" should use the
underscore to separate words, "variable names" should use camelCase,
"constants" in all caps, and "class defs" in titlecase.

def go_and_do_this_for_me_now(self, *args)
self.variableNameHere
MyClassNameHere
THISISACONSTANT -or- THIS_IS_A_CONSTANT


in your example i would have used the following

foo.next_value
foo.value
foo.prev_value

good naming conventions will make your life (and everybody else's)
much easier when debugging code.





From masklinn at masklinn.net  Thu Jul 30 13:10:35 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:10:35 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
Message-ID: <AAAD5E08-8E8E-460E-9703-F6C720DBA38B@masklinn.net>

On 30 Jul 2009, at 18:31 , Falcolas wrote:
> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>
>> 1.) No need to use "()" to call a function with no arguments.
>> Python --> "obj.m2().m3()" --ugly
>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>> Man, i must admit i really like this, and your code will look so much
>> cleaner.
>
> I personally would not prefer this, and would likely continue to use
> (), precisely for code clarity - let me explain:
>
> foo.nextval
> foo.val
> foo.previousval
>
> Which of the calls above referenced instance variables
Well, that's very simple: none of them. In Ruby (as in Smalltalk),  
public instance variables simply don't exist.

> and which ones called functions which changed the internal state of  
> foo?
That you can't say, but neither can you say in Python as they could  
all be properties. And of course just because it's a method doesn't  
mean it mutates the object.

> I would have
> trouble saying, just based on the calls above. I would have to go back
> to the definition or documentation of foo to identify which is doing
> what. On the other hand, the following gives a better clue as to what
> is happening (granted not perfect, but better):
Well... it doesn't give much of a clue no really.


From masklinn at masklinn.net  Thu Jul 30 13:15:14 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:15:14 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
Message-ID: <F3EE917F-FF02-429C-828A-977623E23C60@masklinn.net>

On 30 Jul 2009, at 19:01 , Inky 788 wrote:
> On Jul 30, 12:04 am, alex23 <wuwe... at gmail.com> wrote:
>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>
>>> 1.) No need to use "()" to call a function with no arguments.
>>> Python --> "obj.m2().m3()" --ugly
>>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>>> Man, i must admit i really like this, and your code will look so  
>>> much
>>> cleaner.
>>
>> How do you distinguish between calling a method with no arguments,  
>> and
>> getting access to the method object itself (because it _is_ an  
>> object,
>> y'know, it's OO all the way down...)?
>
> I agree with alex here. Will take the explicit syntax over the extra
> cognitive load of figuring out exactly what's going on with
> `obj.m1.m2.m3`.
There's no cognitive load whatsoever: it's calling methods. Always.  
Ruby simply gives you no other option. Now it could be very simple  
methods to instance attributes, akin to a java getter, but it's still  
only methods.

Furthermore Ruby has a pretty nice convention (sadly not used enough I  
think) taken from Scheme where it's possible to postfix a method name  
with "!" (note: the "!" is part of the name, there's no magic) to  
indicate that this method modifies the object it's called on rather  
than simply returning stuff.



From keith at nekotaku.com  Thu Jul 30 13:16:45 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 10:16:45 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
	<7ddvp0F2brmgrU1@mid.uni-berlin.de>
	<33b7685b-054a-442c-8e97-46a5b77f7900@z4g2000prh.googlegroups.com>
Message-ID: <f2d69d68-66be-4e35-ae04-afe8f5ab625c@l5g2000pra.googlegroups.com>

Winner, winner, chicken dinner... resolved.

http://wwwsearch.sourceforge.net/mechanize/doc.html

import mechanize
cj = mechanize.MSIECookieJar(delayload=True)
cj.load_from_registry()  # finds cookie index file from registry

Thanks Mr Lee!


From mhanbali at teksystems.com  Thu Jul 30 13:22:20 2009
From: mhanbali at teksystems.com (Mehdi H)
Date: Thu, 30 Jul 2009 10:22:20 -0700 (PDT)
Subject: NASA using Python / Django for NEBULA (cloud comp.)
Message-ID: <57859e1d-ff69-49fc-b758-1331912b4d0e@v36g2000yqv.googlegroups.com>

Hello Python devs!

I'm supporting NASA on their NEBULA project and they're looking for
Python / Django experts to join their team here in Mountain View, CA.

If you're interested, let me know and we can talk more on how they're
using Django in their environment!


Thanks,
Mehdi




From robert.kern at gmail.com  Thu Jul 30 13:24:52 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 30 Jul 2009 12:24:52 -0500
Subject: Pyplot
In-Reply-To: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
References: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
Message-ID: <h4sl14$q20$1@ger.gmane.org>

On 2009-07-30 04:02, Kaan AK??T wrote:
> I am a newbee in Python. I have some problem with usage of Pyplot. I
> have a loop that creates plot in every end of it. Problem starts here:
> The first plot is fine but the second one is plotted onto the first
> plot. I use:
>
> plt.cla()
> plt.draw()
> plt.hold(False)
> plt.close()
> plt.clf()
>
> but nothing works. Perhaps I am having a problem with basics, please
> help me if you know something about it.

Create a new window by using figure().

You will want to ask matplotlib questions on the matplotlib mailing list:

   https://lists.sourceforge.net/lists/listinfo/matplotlib-users

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dkatkowski at gmail.com  Thu Jul 30 13:25:58 2009
From: dkatkowski at gmail.com (Feyo)
Date: Thu, 30 Jul 2009 10:25:58 -0700 (PDT)
Subject: Help with Regex for domain names
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
	<mailman.3973.1248969388.8015.python-list@python.org>
Message-ID: <78504224-b114-45f3-a302-95fbd8393443@o6g2000yqj.googlegroups.com>

On Jul 30, 11:56?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Feyo wrote:
> > I'm trying to figure out how to write efficiently write a regex for
> > domain names with a particular top level domain. Let's say, I want to
> > grab all domain names with country codes .us, .au, and .de.
>
> > I could create three different regexs that would work:
> > regex = re.compile(r'[\w\-\.]+\.us)
> > regex = re.compile(r'[\w\-\.]+\.au)
> > regex = re.compile(r'[\w\-\.]+\.de)
>
> > How would I write one to accommodate all three, or, better yet, to
> > accommodate a list of them that I can pass into a method call? Thanks!
>
> ?>
> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')
>
> If you have a list of country codes ["us", "au", "de"] then you can
> build the regular expression from it:
>
> regex = re.compile(r'[\w\-\.]+\.(?:%s)' % '|'.join(domains))

Perfect! Thanks.


From rt8396 at gmail.com  Thu Jul 30 13:28:44 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:28:44 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com> 
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com> 
	<mailman.3976.1248974120.8015.python-list@python.org>
Message-ID: <19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>

On Jul 30, 12:15?pm, Masklinn <maskl... at masklinn.net> wrote:
[snip]
> Furthermore Ruby has a pretty nice convention (sadly not used enough I ?
> think) taken from Scheme where it's possible to postfix a method name ?
> with "!" (note: the "!" is part of the name, there's no magic) to ?
> indicate that this method modifies the object it's called on rather ?
> than simply returning stuff.

Another oddity i did not like at first but must admit is growing on me
  vector.reverse --> returns a new reversed vector
  vector.reverse! --> modifies the instance vector in-place

Of course in python you would do...
  vector.reverse --> in-place
  vector.reversed --> in-place

The above example works pretty good, but this doesn't always "sound"
good. Take for example this...
  point3d.offset --> return a new pt
  point3d.offseted --> What did you say!?!?!

Now try Ruby's way
  point3d.offset!
  point3d.offset

a symbol works better for these things


From rurpy at yahoo.com  Thu Jul 30 13:29:09 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Thu, 30 Jul 2009 10:29:09 -0700 (PDT)
Subject: Help with Regex for domain names
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
	<mailman.3973.1248969388.8015.python-list@python.org>
Message-ID: <0422bf8f-ce59-4de2-a1a4-b16a32e5f152@o15g2000yqm.googlegroups.com>

On Jul 30, 9:56 am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Feyo wrote:
> > I'm trying to figure out how to write efficiently write a regex for
> > domain names with a particular top level domain. Let's say, I want to
> > grab all domain names with country codes .us, .au, and .de.
>
> > I could create three different regexs that would work:
> > regex = re.compile(r'[\w\-\.]+\.us)
> > regex = re.compile(r'[\w\-\.]+\.au)
> > regex = re.compile(r'[\w\-\.]+\.de)
>
> > How would I write one to accommodate all three, or, better yet, to
> > accommodate a list of them that I can pass into a method call? Thanks!
>
>  >
> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')

You might also want to consider that some country
codes such as "co" for Columbia might match more than
you want, for example:

  re.match(r'[\w\-\.]+\.(?:us|au|de|co)', 'foo.boo.com')

will match.


From torriem at gmail.com  Thu Jul 30 13:30:03 2009
From: torriem at gmail.com (Michael Torrie)
Date: Thu, 30 Jul 2009 11:30:03 -0600
Subject: Does python have the capability for driver development ?
In-Reply-To: <94abbddc-dac7-4215-84d1-d4eb3f82724d@h21g2000yqa.googlegroups.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<87skgf83ua.fsf@rsw.digi.com.br>
	<mailman.3929.1248911448.8015.python-list@python.org>
	<94abbddc-dac7-4215-84d1-d4eb3f82724d@h21g2000yqa.googlegroups.com>
Message-ID: <4A71D89B.6030301@gmail.com>

MalC0de wrote:
> please introduce me some resource for system programming, I know that
> python is very well at system programming level.
> thanks

Although it is possible (as others have said) to embed Python the
interpreter into a driver, no one has done that that I know of.  You'd
have to write the driver in C or C++, though, and then provide embed a
python interpreter and then provide a python interface (wrapper code
written in C++) that would expose binary primitives and structures to
python that the OS and driver use.  Sounds like quite an undertaking.  I
embedded a python interpreter in a gina dll once (to write login code in
python).  That's a form of system programming, but not what you're
asking about.

Someone years ago someone embedded the perl interpreter into a Linux
driver allowing some kinds of device drivers to be written in perl.  It
was made more as a curiosity though.

Python is not well-suited to system programming.  It takes extra work
(via the ctypes library or other wrappers) to interface with C structs,
plus calls all have to be marshalled to and from the native C APIs.
Might be cool, though.

System programming in Win32 is very complicated and messy.  What little
system programming I've done in Linux was a dream compared.  Definitely
you'll have to master win32 system programming in C and C++ before you
try to embed python in anything.  I'm sure there are a number of books
on the subject.  That's where I'd start.


From rt8396 at gmail.com  Thu Jul 30 13:33:38 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:33:38 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com> 
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com> 
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
Message-ID: <c87549b5-59d2-4136-988a-7c448750e505@d32g2000yqh.googlegroups.com>

Traceback (most recent post last):
  File "<Confessions of a Python Fanboy>", lines (13,14), in <post>
    vector.reverse --> in-place
    vector.reversed --> in-place
DumbMistakeError:

Of course in python you would do...
  vector.reverse --> in-place
  vector.reversed --> new vector


From jeanmichel at sequans.com  Thu Jul 30 13:37:00 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 30 Jul 2009 19:37:00 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
Message-ID: <4A71DA3C.7060502@sequans.com>

r wrote:
> On Jul 30, 11:31 am, Falcolas <garri... at gmail.com> wrote:
>   
>> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>>
>>     
>>> 1.) No need to use "()" to call a function with no arguments.
>>> Python --> "obj.m2().m3()" --ugly
>>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>>> Man, i must admit i really like this, and your code will look so much
>>> cleaner.
>>>       
>> I personally would not prefer this, and would likely continue to use
>> (), precisely for code clarity - let me explain:
>>
>> foo.nextval
>> foo.val
>> foo.previousval
>>
>> Which of the calls above referenced instance variables, and which ones
>> called functions which changed the internal state of foo? I would have
>> trouble saying, just based on the calls above. I would have to go back
>> to the definition or documentation of foo to identify which is doing
>> what. On the other hand, the following gives a better clue as to what
>> is happening (granted not perfect, but better):
>>
>> foo.nextval()
>> foo.val
>> foo.previousval()
>>
>> ~G
>>     
>
> I held your exact same view before i learned the Ruby language. And
> your veiw makes some good points, however, naming conventions with
> eliminate this problem all together. All "method names" should use the
> underscore to separate words, "variable names" should use camelCase,
> "constants" in all caps, and "class defs" in titlecase.
>
> def go_and_do_this_for_me_now(self, *args)
> self.variableNameHere
> MyClassNameHere
> THISISACONSTANT -or- THIS_IS_A_CONSTANT
>
>
> in your example i would have used the following
>
> foo.next_value
> foo.value
> foo.prev_value
>
> good naming conventions will make your life (and everybody else's)
> much easier when debugging code.
>
>
>
>   
How do I know if foo.value is an attribute or if it is a method that 
returns the foo value ? It seems you can make the difference only when 
tokens are composed of more than one word, not very handy don't you think ?

Just feeding the troll.

JM



From carsten.haese at gmail.com  Thu Jul 30 13:42:30 2009
From: carsten.haese at gmail.com (Carsten Haese)
Date: Thu, 30 Jul 2009 13:42:30 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
Message-ID: <h4sm27$u5j$1@ger.gmane.org>

r wrote:
> Of course in python you would do...
>   vector.reverse --> in-place
>   vector.reversed --> in-place

You do know that only one of those works in-place, right?

> The above example works pretty good, but this doesn't always "sound"
> good. Take for example this...
>   point3d.offset --> return a new pt
>   point3d.offseted --> What did you say!?!?!
> 
> Now try Ruby's way
>   point3d.offset!
>   point3d.offset
> 
> a symbol works better for these things

Or you could use a better verb:

point3d.move -> modifies in place
point3d.moved -> returns a new point

-Carsten



From rt8396 at gmail.com  Thu Jul 30 13:45:49 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:45:49 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com> 
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com> 
	<mailman.3979.1248975429.8015.python-list@python.org>
Message-ID: <91508ea6-a9dd-4d80-81e6-c056c26aae5c@b15g2000yqd.googlegroups.com>

On Jul 30, 12:37?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> r wrote:
> > On Jul 30, 11:31 am, Falcolas <garri... at gmail.com> wrote:
>
> >> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>
> >>> 1.) No need to use "()" to call a function with no arguments.
> >>> Python --> "obj.m2().m3()" --ugly
> >>> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> >>> Man, i must admit i really like this, and your code will look so much
> >>> cleaner.
>
> >> I personally would not prefer this, and would likely continue to use
> >> (), precisely for code clarity - let me explain:
>
> >> foo.nextval
> >> foo.val
> >> foo.previousval
>
> >> Which of the calls above referenced instance variables, and which ones
> >> called functions which changed the internal state of foo? I would have
> >> trouble saying, just based on the calls above. I would have to go back
> >> to the definition or documentation of foo to identify which is doing
> >> what. On the other hand, the following gives a better clue as to what
> >> is happening (granted not perfect, but better):
>
> >> foo.nextval()
> >> foo.val
> >> foo.previousval()
>
> >> ~G
>
> > I held your exact same view before i learned the Ruby language. And
> > your veiw makes some good points, however, naming conventions with
> > eliminate this problem all together. All "method names" should use the
> > underscore to separate words, "variable names" should use camelCase,
> > "constants" in all caps, and "class defs" in titlecase.
>
> > def go_and_do_this_for_me_now(self, *args)
> > self.variableNameHere
> > MyClassNameHere
> > THISISACONSTANT -or- THIS_IS_A_CONSTANT
>
> > in your example i would have used the following
>
> > foo.next_value
> > foo.value
> > foo.prev_value
>
> > good naming conventions will make your life (and everybody else's)
> > much easier when debugging code.
>
> How do I know if foo.value is an attribute or if it is a method that
> returns the foo value ? It seems you can make the difference only when
> tokens are composed of more than one word, not very handy don't you think ?
>
> Just feeding the troll.
>
> JM

You can still use empty parenthesis in Ruby if that floats your boat.

obj.method() <-- note the empty parenthesis

I am just saying don't make them mandatory, thats all. In any case
where ambiguity abounds, by all means use the damn parenthisis.

Now Ruby will even let you call a method *that has arguments* with no
parenthisis -- however, i do not think this is a good idea. Consider
the following

  Geom::Transformation.rotation pt, vec, ang
  bad coder!, bad!
  ...and leads to worn out eyeball parsers in a hurry

  Geom::Transformation.rotation(pt, vec, ang)
  yes, good boy!




From kyosohma at gmail.com  Thu Jul 30 13:45:57 2009
From: kyosohma at gmail.com (Mike Driscoll)
Date: Thu, 30 Jul 2009 10:45:57 -0700 (PDT)
Subject: Bug in IEHtmlWindow?
References: <8a5ed753-d437-45a6-8fee-300eea1207ca@c2g2000yqi.googlegroups.com>
Message-ID: <b48c3835-490b-4434-b74a-8c4449f8cd4a@n11g2000yqb.googlegroups.com>

On Jul 30, 2:54?am, Massi <massi_... at msn.com> wrote:
> Hi everyone, I'm trying to use IEHtmlWindow in my application (python
> 2.5, wxpython 2.8 on win xp). Everything is ok, but I encountered a
> problem which also affects the demo. If I make a research on google a
> strange message appears, saying (I'll try to translate from italian):
>
> Error during execution.
> Do you want to run the debug?
>
> line 29:
> error: 'r' is NULL or it is not an object
>
> Did anybody have the same problem? is it a bug?
> Thanks in advance for your help.

I've never seen that error. Could you re-post to the wxPython user's
list? They can probably help you there: http://groups.google.com/group/wxPython

Mike


From digitig at gmail.com  Thu Jul 30 13:47:04 2009
From: digitig at gmail.com (Tim Rowe)
Date: Thu, 30 Jul 2009 18:47:04 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <aee48b3c0907301047s7a69080epe2228477e9f51610@mail.gmail.com>

2009/7/30 r <rt8396 at gmail.com>:
>
> Like your
> first lay, your first programing language can leave an indelible mark
> on you

That's true. FOCAL scarred me for life.

> but i now realize Ruby has some good
> things going for it.

Any language that gets any sort of real use has to have. For instance,
I love Ada's numeric types (you can specify either the minimum number
of significant figures or the maximum delta for a real type, and it
will give you a type that satisfies that -- or a compilation error if
it can't.  That matches genuine problem domains far better than having
to remember how many bits in a double on this particular system, and
reduces portability bugs).

> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max(). You know what i am talking about here people. We
> all get complacent and It seems easier to just cope with these
> problems instead of fighting for change. But look at the French, ?WHAT
> THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!

I seem to recall recent studies showing that the French were on
average happier than Brits or Americans. Don't knock it!

> As for the rest of Ruby, i am not impressed. The redundant usage of
> "end" over indention perplexes me. The Perlish feel of "require" and
> the horrifically cryptic idioms of Ruby regular expressions. The
> "puts" and "gets" seem childish and the math class does not even have
> a degrees or radians function!

The operating system dependency built into the language did it for me.
That and the fact that I couldn't stop laughing for long enough to
learn any more when I read in the Pragmatic Programmer's Guide that
"Ruby, unlike less flexible languages, lets you alter the value of a
constant." Yep, as they say "Bug" = "Undocumented feature"!

-- 
Tim Rowe


From masklinn at masklinn.net  Thu Jul 30 13:56:07 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:56:07 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4A71DA3C.7060502@sequans.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
	<4A71DA3C.7060502@sequans.com>
Message-ID: <EFEC96C0-CA5C-49CA-803B-A2F1CF251CAB@masklinn.net>

On 30 Jul 2009, at 19:37 , Jean-Michel Pichavant wrote:
> r wrote:
>> On Jul 30, 11:31 am, Falcolas <garri... at gmail.com> wrote:
>>
>>> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>>>
>>>
>>>> 1.) No need to use "()" to call a function with no arguments.
>>>> Python --> "obj.m2().m3()" --ugly
>>>>  Ruby --> "obj.m1.m2.m3"  -- sweeet!
>>>> Man, i must admit i really like this, and your code will look so  
>>>> much
>>>> cleaner.
>>>>
>>> I personally would not prefer this, and would likely continue to use
>>> (), precisely for code clarity - let me explain:
>>>
>>> foo.nextval
>>> foo.val
>>> foo.previousval
>>>
>>> Which of the calls above referenced instance variables, and which  
>>> ones
>>> called functions which changed the internal state of foo? I would  
>>> have
>>> trouble saying, just based on the calls above. I would have to go  
>>> back
>>> to the definition or documentation of foo to identify which is doing
>>> what. On the other hand, the following gives a better clue as to  
>>> what
>>> is happening (granted not perfect, but better):
>>>
>>> foo.nextval()
>>> foo.val
>>> foo.previousval()
>>>
>>> ~G
>>>
>>
>> I held your exact same view before i learned the Ruby language. And
>> your veiw makes some good points, however, naming conventions with
>> eliminate this problem all together. All "method names" should use  
>> the
>> underscore to separate words, "variable names" should use camelCase,
>> "constants" in all caps, and "class defs" in titlecase.
>>
>> def go_and_do_this_for_me_now(self, *args)
>> self.variableNameHere
>> MyClassNameHere
>> THISISACONSTANT -or- THIS_IS_A_CONSTANT
>>
>>
>> in your example i would have used the following
>>
>> foo.next_value
>> foo.value
>> foo.prev_value
>>
>> good naming conventions will make your life (and everybody else's)
>> much easier when debugging code.
>>
> How do I know if foo.value is an attribute or if it is a method that  
> returns the foo value ?
It cannot be an attribute. Ruby doesn't give access to attributes,  
they're always solely private (as in Smalltalk). Also you shouldn't  
reply to r, he has no idea about what he's talking about.



From masklinn at masklinn.net  Thu Jul 30 13:57:54 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:57:54 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <h4sm27$u5j$1@ger.gmane.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<h4sm27$u5j$1@ger.gmane.org>
Message-ID: <92229A0F-EC80-43C7-97B8-8C3636581EDE@masklinn.net>

On 30 Jul 2009, at 19:42 , Carsten Haese wrote:
> r wrote:
>> Of course in python you would do...
>>  vector.reverse --> in-place
>>  vector.reversed --> in-place
>
> You do know that only one of those works in-place, right?
>
Well mostly because the other one doesn't exist (as python has  
`lst.reverse()` but `reversed(lst)`) but he was probably talking  
hypothetically. Or something.


From user at example.net  Thu Jul 30 14:05:53 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 20:05:53 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
Message-ID: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>

r wrote:
> On Jul 30, 12:15 pm, Masklinn <maskl... at masklinn.net> wrote:
> [snip]
> 
>>Furthermore Ruby has a pretty nice convention (sadly not used enough I  
>>think) taken from Scheme where it's possible to postfix a method name  
>>with "!" (note: the "!" is part of the name, there's no magic) to  
>>indicate that this method modifies the object it's called on rather  
>>than simply returning stuff.
> 
> 
> Another oddity i did not like at first but must admit is growing on me
>   vector.reverse --> returns a new reversed vector
>   vector.reverse! --> modifies the instance vector in-place
> 
> Of course in python you would do...
>   vector.reverse --> in-place
>   vector.reversed --> in-place
> 

how to reverse a string in python? must i usa a temp? like:

 >>> s = "ciccio"
 >>> l = list(s)
 >>> l.reverse()
 >>> s = "".join(l)
 >>> s
'oiccic'
 >>>

???

bye



From garrickp at gmail.com  Thu Jul 30 14:06:33 2009
From: garrickp at gmail.com (Falcolas)
Date: Thu, 30 Jul 2009 11:06:33 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com> 
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com> 
	<4A71DA3C.7060502@sequans.com>
	<mailman.3982.1248976579.8015.python-list@python.org>
Message-ID: <776cafad-cfe8-442d-8d40-cab4e5c71d9b@c14g2000yqm.googlegroups.com>

On Jul 30, 11:56?am, Masklinn <maskl... at masklinn.net> wrote:
> On 30 Jul 2009, at 19:37 , Jean-Michel Pichavant wrote:
>
> > r wrote:

> > How do I know if foo.value is an attribute or if it is a method that ?
> > returns the foo value ?
>
> It cannot be an attribute. Ruby doesn't give access to attributes, ?
> they're always solely private (as in Smalltalk). Also you shouldn't ?
> reply to r, he has no idea about what he's talking about.

That doesn't sound like a feature I would appreciate much, though I am
a big fan of "we're all adults here" programming. Though if they are
all functions, then adding parentheses wouldn't make much difference,
so offering the option of getting rid of them makes sense.

>> I would have
>> trouble saying, just based on the calls above. I would have to go back
>> to the definition or documentation of foo to identify which is doing
>> what. On the other hand, the following gives a better clue as to what
>> is happening (granted not perfect, but better):

> Well... it doesn't give much of a clue no really.

It, with few exceptions, tells me that fetching the value foo.val will
not modify the state of foo. Important stuff, at least to me.


From user at example.net  Thu Jul 30 14:08:36 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 20:08:36 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.3981.1248976469.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
Message-ID: <4a71e1a5$0$40016$4fafbaef@reader3.news.tin.it>

Tim Rowe wrote:
> 2009/7/30 r <rt8396 at gmail.com>:
> 
>>Like your
>>first lay, your first programing language can leave an indelible mark
>>on you
> 
> 
> That's true. FOCAL scarred me for life.
> 
> 
>>but i now realize Ruby has some good
>>things going for it.
> 
> 
> Any language that gets any sort of real use has to have. For instance,
> I love Ada's numeric types (you can specify either the minimum number
> of significant figures or the maximum delta for a real type, and it
> will give you a type that satisfies that -- or a compilation error if
> it can't.  That matches genuine problem domains far better

doesn't the decimal module do some of that too?

bye


From darkneter at gmail.com  Thu Jul 30 14:13:44 2009
From: darkneter at gmail.com (NighterNet)
Date: Thu, 30 Jul 2009 11:13:44 -0700 (PDT)
Subject: class or thread id count
Message-ID: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>

Need some help on doing some bit simple id count. It like every time
it create a class or thread there is id++. Python 3.1

example:
class ClientThread (threading.Thread):
   def __init__(self,clientSocket):
      threading.Thread.__init__(self)
         self.id += 1;

Not sure it how it works.


From python at mrabarnett.plus.com  Thu Jul 30 14:20:11 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 19:20:11 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <4A71E45B.3070009@mrabarnett.plus.com>

superpollo wrote:
> r wrote:
>> On Jul 30, 12:15 pm, Masklinn <maskl... at masklinn.net> wrote:
>> [snip]
>>
>>> Furthermore Ruby has a pretty nice convention (sadly not used enough 
>>> I  think) taken from Scheme where it's possible to postfix a method 
>>> name  with "!" (note: the "!" is part of the name, there's no magic) 
>>> to  indicate that this method modifies the object it's called on 
>>> rather  than simply returning stuff.
>>
>>
>> Another oddity i did not like at first but must admit is growing on me
>>   vector.reverse --> returns a new reversed vector
>>   vector.reverse! --> modifies the instance vector in-place
>>
>> Of course in python you would do...
>>   vector.reverse --> in-place
>>   vector.reversed --> in-place
>>
> 
> how to reverse a string in python? must i usa a temp? like:
> 
>  >>> s = "ciccio"
>  >>> l = list(s)
>  >>> l.reverse()
>  >>> s = "".join(l)
>  >>> s
> 'oiccic'
>  >>>
> 
> ???
> 
Use slicing with a step of -1:

 >>> s = "ciccio"
 >>> s[::-1]
'oiccic'



From masklinn at masklinn.net  Thu Jul 30 14:22:21 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 20:22:21 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <772E43D2-61B0-4C26-AAA3-C1E9785176AF@masklinn.net>

On 30 Jul 2009, at 20:05 , superpollo wrote:
> r wrote:
>> On Jul 30, 12:15 pm, Masklinn <maskl... at masklinn.net> wrote:
>> [snip]
>>> Furthermore Ruby has a pretty nice convention (sadly not used  
>>> enough I  think) taken from Scheme where it's possible to postfix  
>>> a method name  with "!" (note: the "!" is part of the name,  
>>> there's no magic) to  indicate that this method modifies the  
>>> object it's called on rather  than simply returning stuff.
>> Another oddity i did not like at first but must admit is growing on  
>> me
>>  vector.reverse --> returns a new reversed vector
>>  vector.reverse! --> modifies the instance vector in-place
>> Of course in python you would do...
>>  vector.reverse --> in-place
>>  vector.reversed --> in-place
>
> how to reverse a string in python? must i usa a temp? like:
>
> >>> s = "ciccio"
> >>> l = list(s)
> >>> l.reverse()
> >>> s = "".join(l)
> >>> s
> 'oiccic'
> >>>
>
> ???
>
> bye

s = s[::-1]


From masklinn at masklinn.net  Thu Jul 30 14:24:23 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 20:24:23 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <776cafad-cfe8-442d-8d40-cab4e5c71d9b@c14g2000yqm.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
	<4A71DA3C.7060502@sequans.com>
	<mailman.3982.1248976579.8015.python-list@python.org>
	<776cafad-cfe8-442d-8d40-cab4e5c71d9b@c14g2000yqm.googlegroups.com>
Message-ID: <EB4CC38B-C038-45F2-BC37-CC87B712C0A2@masklinn.net>

On 30 Jul 2009, at 20:06 , Falcolas wrote:
> On Jul 30, 11:56 am, Masklinn <maskl... at masklinn.net> wrote:
>> On 30 Jul 2009, at 19:37 , Jean-Michel Pichavant wrote:
>>
>>> r wrote:
>
>>> How do I know if foo.value is an attribute or if it is a method that
>>> returns the foo value ?
>>
>> It cannot be an attribute. Ruby doesn't give access to attributes,
>> they're always solely private (as in Smalltalk). Also you shouldn't
>> reply to r, he has no idea about what he's talking about.
>
> That doesn't sound like a feature I would appreciate much, though I am
> a big fan of "we're all adults here" programming. Though if they are
> all functions, then adding parentheses wouldn't make much difference,
> so offering the option of getting rid of them makes sense.
>
That's pretty much it.

>>> I would have
>>> trouble saying, just based on the calls above. I would have to go  
>>> back
>>> to the definition or documentation of foo to identify which is doing
>>> what. On the other hand, the following gives a better clue as to  
>>> what
>>> is happening (granted not perfect, but better):
>
>> Well... it doesn't give much of a clue no really.
>
> It, with few exceptions, tells me that fetching the value foo.val will
> not modify the state of foo. Important stuff, at least to me.
But because of those few exceptions, it really tells you that foo.val  
*probably* doesn't modify the state of foo. Unless you go source- 
diving, you can't know for sure. Only Haskell gives you that kind of  
guarantees (and even then, the code you call could have an unsafe*  
somewhere)


From davea at ieee.org  Thu Jul 30 14:28:11 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 14:28:11 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <4A71E63B.6080200@ieee.org>

superpollo wrote:
>> <snip>
>
> how to reverse a string in python? must i usa a temp? like:
>
> >>> s = "ciccio"
> >>> l = list(s)
> >>> l.reverse()
> >>> s = "".join(l)
> >>> s
> 'oiccic'
> >>>
>
> ???
>
> bye
>
>
> </div>
>
simply     s = s[::-1]

DaveA



From user at example.net  Thu Jul 30 14:30:45 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 20:30:45 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.3985.1248978012.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
	<mailman.3985.1248978012.8015.python-list@python.org>
Message-ID: <4a71e6d6$0$40004$4fafbaef@reader3.news.tin.it>

MRAB wrote:
> superpollo wrote:
...
>> how to reverse a string in python? must i usa a temp? like:
>>
>>  >>> s = "ciccio"
>>  >>> l = list(s)
>>  >>> l.reverse()
>>  >>> s = "".join(l)
>>  >>> s
>> 'oiccic'
>>  >>>
>>
>> ???
>>
> Use slicing with a step of -1:
> 
>  >>> s = "ciccio"
>  >>> s[::-1]
> 'oiccic'

lol

bye


From hniksic at xemacs.org  Thu Jul 30 14:32:10 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Thu, 30 Jul 2009 20:32:10 +0200
Subject: New implementation of re module
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<200907301235.22563.wolfgang@rohdewald.de>
	<4A717E96.3020900@mrabarnett.plus.com>
	<200907301429.07850.wolfgang@rohdewald.de>
	<mailman.3958.1248958592.8015.python-list@python.org>
Message-ID: <87y6q6dnth.fsf@busola.homelinux.net>

MRAB <python at mrabarnett.plus.com> writes:

> So it complains about:
>
>     ++(RE_CHAR*)context->text_ptr
>
> but not about:
>
>     ++info->repeat.count
>
> Does this mean that the gcc compiler thinks that the cast makes it an
> rvalue?

The cast operator does return an rvalue, treating it otherwise used to
be an extension to popular compilers, including ironically gcc.  The
standard-compliant way of writing the above would be:

++ *(RE_CHAR **) &context->text_ptr


From wells at submute.net  Thu Jul 30 14:45:53 2009
From: wells at submute.net (Wells Oliver)
Date: Thu, 30 Jul 2009 13:45:53 -0500
Subject: Sorting dict by value w/ operator.itemgetter- using key name?
Message-ID: <3f1a902d0907301145t2aa559b7ifcb3dc45d9b7a363@mail.gmail.com>

Bit of code:

print sorted(results.items(), key=operator.itemgetter(1))

Would rather use 'H9', which is the name of the key in position 1 like:

print sorted(results.items(), key=operator.itemgetter('H9'))

Obviously that ain't work else I wouldn't be sending this email. Any tips?

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/7236657b/attachment.html>

From nobody at nowhere.com  Thu Jul 30 14:51:23 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 30 Jul 2009 19:51:23 +0100
Subject: Help with Regex for domain names
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
	<mailman.3973.1248969388.8015.python-list@python.org>
	<0422bf8f-ce59-4de2-a1a4-b16a32e5f152@o15g2000yqm.googlegroups.com>
Message-ID: <pan.2009.07.30.18.51.22.890000@nowhere.com>

On Thu, 30 Jul 2009 10:29:09 -0700, rurpy wrote:

>> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')
> 
> You might also want to consider that some country
> codes such as "co" for Columbia might match more than
> you want, for example:
> 
>   re.match(r'[\w\-\.]+\.(?:us|au|de|co)', 'foo.boo.com')
> 
> will match.

... so put \b at the end, i.e.:

regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)\b')



From sri_annauni at yahoo.co.in  Thu Jul 30 15:04:09 2009
From: sri_annauni at yahoo.co.in (srinivasan srinivas)
Date: Fri, 31 Jul 2009 00:34:09 +0530 (IST)
Subject: calling obect method
Message-ID: <960855.56660.qm@web7906.mail.in.yahoo.com>

Hi,
I would like to know if i have an object and one of its methods as a string. How to call the method using this string?
For ex
If object is x and string y has one of its method names. 
x.value(y)() ---. Is there a way to do this?

Thanks,
Srini


      See the Web&#39;s breaking stories, chosen by people like you. Check out Yahoo! Buzz. http://in.buzz.yahoo.com/


From rt8396 at gmail.com  Thu Jul 30 15:08:25 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 12:08:25 -0700 (PDT)
Subject: calling obect method
References: <mailman.3990.1248980658.8015.python-list@python.org>
Message-ID: <2e8c5c91-be27-430b-9cad-46a5bff3ee37@26g2000yqk.googlegroups.com>

>>> import math
>>> getattr(math, 'hypot')(3,4)
5.0


From rt8396 at gmail.com  Thu Jul 30 15:14:12 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 12:14:12 -0700 (PDT)
Subject: class or thread id count
References: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>
Message-ID: <f0446213-638e-41de-b2e8-6c35a1f90004@c2g2000yqi.googlegroups.com>

On Jul 30, 1:13?pm, NighterNet <darkne... at gmail.com> wrote:
> Need some help on doing some bit simple id count. It like every time
> it create a class or thread there is id++. Python 3.1
>
> example:
> class ClientThread (threading.Thread):
> ? ?def __init__(self,clientSocket):
> ? ? ? threading.Thread.__init__(self)
> ? ? ? ? ?self.id += 1;
>
> Not sure it how it works.

use a class atrribute

>>> class Person():
	count = 0
	def __init__(self, name, info):
		self.name = name
		self.info = info
		Person.count+=1


>>> p1 = Person('alex23', 'very annoying')
>>> p2 = Person('Guido', 'very intelligent')
>>> p2.count
2
>>> p1.count
2
>>> Person.count
2


From zuo at chopin.edu.pl  Thu Jul 30 15:20:21 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 21:20:21 +0200
Subject: socket send
In-Reply-To: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
Message-ID: <op.uxwan7s3fvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 o 05:52:06 NighterNet <darkneter at gmail.com> wrote:

> I am trying to figure out how to send text or byte in python 3.1. I am
> trying to send data to flash socket to get there. I am not sure how to
> work it.
>
> buff= 'id=' , self.id , ':balive=False\n'
> clientSock.send(buff);

And what is the problem?

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From bdezonia at wisc.edu  Thu Jul 30 15:36:18 2009
From: bdezonia at wisc.edu (BDZ)
Date: Thu, 30 Jul 2009 12:36:18 -0700 (PDT)
Subject: os.path.exists() and Samba shares
Message-ID: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>

Hello. I have written a Python 3.1 script running on Windows that uses
os.path.exists() to connect to network shares. If the various network
shares require different user account and password combos than the
account the script is running under the routine returns false. I need
something like os.samba.path.exists(username,password,path). Does
anyone have a suggestion on how I can accomplish what I need to do in
Python?


From martin at v.loewis.de  Thu Jul 30 15:56:24 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Thu, 30 Jul 2009 21:56:24 +0200
Subject: No PyPI search for 3.x compatible packages
In-Reply-To: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
Message-ID: <4a71fae9$0$10471$9b622d9e@news.freenet.de>

Neil Hodgson wrote:
>    There appears to be no way to search PyPI for packages that are
> compatible with Python 3.x. There are classifiers for 'Programming
> Language' including 'Programming Language :: Python :: 3' but that seems
> to be for implementation language since there are so many packages that
> specify C. 

Not at all. The Trove classifiers *always* mean what the package author
wants them to mean. In the specific case of Python :: 3, they should
mean what makes most sense. For an application, it might make most sense
to specify the language it is written in. For a Python library, it
surely would make most sense to specify the Python version it supports -
notice, however, that this is *also* the Python version the library is
written in.

Regards,
Martin


From darkneter at gmail.com  Thu Jul 30 16:09:36 2009
From: darkneter at gmail.com (NighterNet)
Date: Thu, 30 Jul 2009 13:09:36 -0700 (PDT)
Subject: class or thread id count
References: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>
	<f0446213-638e-41de-b2e8-6c35a1f90004@c2g2000yqi.googlegroups.com>
Message-ID: <68b09353-7e30-4df2-8e05-32159b03414a@f20g2000prn.googlegroups.com>

On Jul 30, 12:14?pm, r <rt8... at gmail.com> wrote:
> On Jul 30, 1:13?pm, NighterNet <darkne... at gmail.com> wrote:
>
> > Need some help on doing some bit simple id count. It like every time
> > it create a class orthreadthere is id++. Python 3.1
>
> > example:
> > class ClientThread (threading.Thread):
> > ? ?def __init__(self,clientSocket):
> > ? ? ? threading.Thread.__init__(self)
> > ? ? ? ? ?self.id += 1;
>
> > Not sure it how it works.
>
> use a class atrribute
>
> >>> class Person():
>
> ? ? ? ? count = 0
> ? ? ? ? def __init__(self, name, info):
> ? ? ? ? ? ? ? ? self.name = name
> ? ? ? ? ? ? ? ? self.info = info
> ? ? ? ? ? ? ? ? Person.count+=1
>
> >>> p1 = Person('alex23', 'very annoying')
> >>> p2 = Person('Guido', 'very intelligent')
> >>> p2.count
> 2
> >>> p1.count
> 2
> >>> Person.count
>
> 2

Thanks it work.

class Person():
  count = 0
  def __init__(self, name, info):
      self.name = name
      self.info = info
      Person.count+=1
      self.count = Person.count


From zuo at chopin.edu.pl  Thu Jul 30 16:16:13 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 22:16:13 +0200
Subject: socket send
In-Reply-To: <41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com>
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com>
Message-ID: <op.uxwc9be4fvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 o 12:29:24 Francesco Bochicchio <bieffe62 at gmail.com> wrote:

> On Jul 30, 5:52?am, NighterNet <darkne... at gmail.com> wrote:
>> I am trying to figure out how to send text or byte in python 3.1. I am
>> trying to send data to flash socket to get there. I am not sure how to
>> work it.
>>
>> buff= 'id=' , self.id , ':balive=False\n'
>> clientSock.send(buff);
>
> Try putting a 'b' before the constant string that you want to send:
>
> >>> type(b'123')
> <class 'bytes'>

It's true. In python '...' literals are for strings ('str' type) and
b'...' literals are for binary data (bytes type).

Sockets' send() and recv() need binary data ('bytes' objects).

> or use something like this to convert non constant strings (with only
> ASCII characters) into bytes:

> >>> s = "A non-constant string : %d " % n
> >>> s
> 'A non-constant string : 12 '
> >>> type(s)
> <class 'str'>

What???

'str' type in Python 3.x IS NOT a type of "non-constant" strings and
IS NOT a type of strings "with only ASCII characters"!

'str' type in Python 3.x *is* the type of immutable ('constant') and
Unicode character (Unicode, not only ASCII) strings. It's the same what
'unicode' type in Python 2.x.

'bytes' type objects in Python 3.x are also immutable. They are good
for binary data (also text data encoded to binary data; see below).

'bytearray' type objects are like 'bytes', but mutable (like e. g.
lists).

>>>> b = bytes ( ord(c) for c in s )
>>>> b
> b'A non-constant string : 12 '
>
> You could also use struct.pack , that in python 3.x returns bytes and
> not strings. In this case you need to specify the size of the string
> (extra bytes are zero-filled):
>
> import struct

What for all that weird actions???

* Simply do:

bytes_object = str_object.encode(<encoding>)
or
bytes_object = bytes(str_object, <encoding>)

-- where <encoding> could be e.g. 'ascii', 'utf-8', 'iso-8859-1' etc.;
using the former method, you can omit this argument -> then default
encoding will be used (usualy 'utf-8').

* As easily as that, you can convert bytes to str:

str_object = bytes_object.decode(<encoding>)
or
str_object = str(bytes_object, <encoding>)

* Some examples:

  >>> 'What makes you think she is a witch?'  # it's str
  'What makes you think she is a witch?'
  >>> 'What makes you think she is a witch?'.encode()  # to bytes
  b'What makes you think she is a witch?'
  >>> 'What makes you think she is a witch?'.encode('utf-8')  # to bytes
  b'What makes you think she is a witch?'
  >>> bytes('What makes you think she is a witch?')  # to bytes???
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  TypeError: string argument without an encoding
  >>> bytes('What makes you think she is a witch?', 'ascii')  # to bytes
  b'What makes you think she is a witch?'

  >>> b'What makes you think she is a witch?'.decode()  # to str
  'What makes you think she is a witch?'
  >>> b'What makes you think she is a witch?'.decode('utf-8')  # to str
  'What makes you think she is a witch?'
  >>> str(b'What makes you think she is a witch?', 'utf-8')  # to str
  'What makes you think she is a witch?'
  >>> str(b'What makes you think she is a witch?')  # but not this way
  "b'What makes you think she is a witch?'"
  [^ note this]

Cheers,

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From zuo at chopin.edu.pl  Thu Jul 30 16:23:32 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 22:23:32 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
Message-ID: <op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:

> On 30 Jul 2009, at 06:04 , alex23 wrote:
>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>> 2.) the .each method
>>> container.each{|localVar| block}
>>> This method can really cleanup some ugly for loops, although i really
>>> like the readability of for loops.
>>
>> map(lambda localVar: <block>, sequence)
>>
>> or:
>>
>> def usefully_named_func(var):
>>    <block>
>>    return var
>>
>> transformed = [usefully_named_func(v) for v in sequence]
>>
> The issue here is of course that `map` and comprehensions are  
> transformations. `#each` exists for effectful iterations (Ruby has  
> `#map` for the map operation). So the intent expressed by `#each` and  
> `map` isn't the same. Furthermore and this is the most problematic  
> limitation of Python here, `lambda` doesn't allow complex  
> transformations due to its restrictions, so one has to switch to named  
> functions which works but isn't sexy (and tends to lower readability  
> imo).

I don't see any real limitation. What's wrong in:

for localVar in container:
     block

And ruby's container.each is very similar to Python's iter()

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From masklinn at masklinn.net  Thu Jul 30 16:41:57 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 22:41:57 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>

On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
> 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
>
>> On 30 Jul 2009, at 06:04 , alex23 wrote:
>>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>>> 2.) the .each method
>>>> container.each{|localVar| block}
>>>> This method can really cleanup some ugly for loops, although i  
>>>> really
>>>> like the readability of for loops.
>>>
>>> map(lambda localVar: <block>, sequence)
>>>
>>> or:
>>>
>>> def usefully_named_func(var):
>>>   <block>
>>>   return var
>>>
>>> transformed = [usefully_named_func(v) for v in sequence]
>>>
>> The issue here is of course that `map` and comprehensions are  
>> transformations. `#each` exists for effectful iterations (Ruby has  
>> `#map` for the map operation). So the intent expressed by `#each`  
>> and `map` isn't the same. Furthermore and this is the most  
>> problematic limitation of Python here, `lambda` doesn't allow  
>> complex transformations due to its restrictions, so one has to  
>> switch to named functions which works but isn't sexy (and tends to  
>> lower readability imo).
>
> I don't see any real limitation. What's wrong in:
>
> for localVar in container:
>    block
>
Well what's wrong with using that rather than `map`, `filter` or a  
list comprehension? (and if you don't see what the limitations of  
`lambda` are, you probably very rarely use it)

> And ruby's container.each is very similar to Python's iter()
>
Uh? not at all?



From tjreedy at udel.edu  Thu Jul 30 16:55:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 16:55:17 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <h4t1bj$4ut$1@ger.gmane.org>

superpollo wrote:
> r wrote:

> how to reverse a string in python? must i usa a temp? like:
> 
>  >>> s = "ciccio"
>  >>> l = list(s)
>  >>> l.reverse()
>  >>> s = "".join(l)
>  >>> s
> 'oiccic'
>  >>>
> 
> ???

No.
 >>> ''.join(list(reversed('abc')))
'cba'
 >>> 'abc'[2::-1]
'cba'
 >>> 'abc'[1000000000::-1]
'cba'

Any int >= len(string)-1 will do, so the call to len will usually not be 
necessary.

Needing strings reversed is not common.  More common might be

for char in reversed(somestring): process(char)

Terry Jan Reedy



From rt8396 at gmail.com  Thu Jul 30 17:02:03 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 14:02:03 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com> 
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com> 
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
	<mailman.3995.1248987328.8015.python-list@python.org>
Message-ID: <39013d06-e281-4459-bdb2-19831c9526ea@k1g2000yqf.googlegroups.com>

On Jul 30, 3:55?pm, Terry Reedy <tjre... at udel.edu> wrote:
> superpollo wrote:
> > r wrote:
> > how to reverse a string in python? must i usa a temp? like:
[snip]
> Terry Jan Reedy

No "r" never wrote anything like that. reversing a string is RTFM
material, this is basic stuff here! Stop quoting me as saying things i
did not say! I never asked how to reverse a string, "superpollo"
did.


From tjreedy at udel.edu  Thu Jul 30 17:02:20 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 17:02:20 -0400
Subject: Sorting dict by value w/ operator.itemgetter- using key name?
In-Reply-To: <3f1a902d0907301145t2aa559b7ifcb3dc45d9b7a363@mail.gmail.com>
References: <3f1a902d0907301145t2aa559b7ifcb3dc45d9b7a363@mail.gmail.com>
Message-ID: <h4t1oq$4ut$2@ger.gmane.org>

Wells Oliver wrote:
> Bit of code:
> 
> print sorted(results.items(), key=operator.itemgetter(1))
> 
> Would rather use 'H9', which is the name of the key in position 1 like:
> 
> print sorted(results.items(), key=operator.itemgetter('H9'))
> 
> Obviously that ain't work else I wouldn't be sending this email. Any tips?

Suppose namepos=['H9':1,} etc, then itemgetter(namepos['H9'])



From ethan at stoneleaf.us  Thu Jul 30 17:04:21 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 30 Jul 2009 14:04:21 -0700
Subject: Regexp problem
In-Reply-To: <h4s7pm$rgr$1@adenine.netfront.net>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>	<mailman.3961.1248959276.8015.python-list@python.org>	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
	<h4s7pm$rgr$1@adenine.netfront.net>
Message-ID: <4A720AD5.1030202@stoneleaf.us>

Marcus Wanner wrote:
> On 7/30/2009 9:32 AM, Beldar wrote:
> 
>> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>>
>>> Beldar wrote:
>>>
>>>> Hi there!
>>>> I have a problem and i'm not very good at regular expressions.
>>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>>> 'something-is-listening', i need to get the something part, use it in
>>>> my code, and then replace the whole 'something-is-listening' for
>>>> another string.
>>>
>>> \w+ will match a word and enclosing it in (...) will capture what was
>>> matched:
>>>
>>>      m = re.search(r"(\w+)-is-listening", text)
>>>      print "Captured '%s'" % m.group(1)
>>>      print "Matched from %d to %d" % (m.start(), m.end())
>>
>>
>> Ok, thank you all, it was very helpful!
> 
> Wow, I really need to learn more about regexp...
> Any tutorials you guys can recommend?
> 
> Marcus

Mastering Regular Expressions
Powerful Techniques for Perl and Other Tools
By Jeffrey E. F. Friedl

Great book!

~Ethan~


From python at mrabarnett.plus.com  Thu Jul 30 17:28:55 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 22:28:55 +0100
Subject: Help with Regex for domain names
In-Reply-To: <pan.2009.07.30.18.51.22.890000@nowhere.com>
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>	<mailman.3973.1248969388.8015.python-list@python.org>	<0422bf8f-ce59-4de2-a1a4-b16a32e5f152@o15g2000yqm.googlegroups.com>
	<pan.2009.07.30.18.51.22.890000@nowhere.com>
Message-ID: <4A721097.50201@mrabarnett.plus.com>

Nobody wrote:
> On Thu, 30 Jul 2009 10:29:09 -0700, rurpy wrote:
> 
>>> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')
>> You might also want to consider that some country
>> codes such as "co" for Columbia might match more than
>> you want, for example:
>>
>>   re.match(r'[\w\-\.]+\.(?:us|au|de|co)', 'foo.boo.com')
>>
>> will match.
> 
> ... so put \b at the end, i.e.:
> 
> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)\b')
> 
It would still match "www.bbc.co.uk", so you might need:

regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)\b(?!\.\b)')


From emmanuel.surleau at gmail.com  Thu Jul 30 17:29:21 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Thu, 30 Jul 2009 23:29:21 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <200907302329.21286.emmanuel.surleau@gmail.com>

> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.

It has benefits - code does look better. It has also significant cons - it is 
ambiguous.
For instance:

a = b

Is b a variable or a method called without parameter?

> 2.) the .each method
> container.each{|localVar| block}
> This method can really cleanup some ugly for loops, although i really
> like the readability of for loops.

It's not only the 'each' method. It's "anonymous callbacks everywhere", which 
is pretty cool. Certainly one of my favourite features of Ruby.

> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max(). You know what i am talking about here people. We
> all get complacent and It seems easier to just cope with these
> problems instead of fighting for change.

While ob.length() is more clear to read, it follows the same "operator" logic 
as __iter__. Which is OK, I suppose.

> But look at the French,  WHAT
> THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!

I assume this was supposed to be funny?

> As for the rest of Ruby, i am not impressed. The redundant usage of
> "end" over indention perplexes me.

You have the choice to use {}. If you are confused over languages which do not 
use indentation to delimit code blocks, you should probably try out a few 
languages outside Python.

> The Perlish feel of "require" and
> the horrifically cryptic idioms of Ruby regular expressions.

Cryptic idioms of Ruby regular expressions? They are Perl-like regular 
expressions, not exactly a far cry from what re does. Also, you can chain 
them, which is extremely nice.

> The "puts" and "gets" seem childish

Well, they're short and easy. Writing "gets" is more intuitive than using 
raw_input()

> and the math class does not even have
> a degrees or radians function!
>
> Anyway, i thought i would get this off my chest and catch up with old
> friends in the meantime. We can all make Python the perfect language
> it needs to be, but it ain't gonna be easy!
> Thank you all
>
> PS stay tuned for more from this series....

Cheers,

Emm


From python at mrabarnett.plus.com  Thu Jul 30 17:40:46 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 22:40:46 +0100
Subject: Regexp problem
In-Reply-To: <4A720AD5.1030202@stoneleaf.us>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>	<mailman.3961.1248959276.8015.python-list@python.org>	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>	<h4s7pm$rgr$1@adenine.netfront.net>
	<4A720AD5.1030202@stoneleaf.us>
Message-ID: <4A72135E.7060205@mrabarnett.plus.com>

Ethan Furman wrote:
> Marcus Wanner wrote:
>> On 7/30/2009 9:32 AM, Beldar wrote:
>>
>>> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>>>
>>>> Beldar wrote:
>>>>
>>>>> Hi there!
>>>>> I have a problem and i'm not very good at regular expressions.
>>>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>>>> 'something-is-listening', i need to get the something part, use it in
>>>>> my code, and then replace the whole 'something-is-listening' for
>>>>> another string.
>>>>
>>>> \w+ will match a word and enclosing it in (...) will capture what was
>>>> matched:
>>>>
>>>>      m = re.search(r"(\w+)-is-listening", text)
>>>>      print "Captured '%s'" % m.group(1)
>>>>      print "Matched from %d to %d" % (m.start(), m.end())
>>>
>>>
>>> Ok, thank you all, it was very helpful!
>>
>> Wow, I really need to learn more about regexp...
>> Any tutorials you guys can recommend?
>>
>> Marcus
> 
> Mastering Regular Expressions
> Powerful Techniques for Perl and Other Tools
> By Jeffrey E. F. Friedl
> 
> Great book!
> 
+1

I have the first edition, seventh printing (December 1998). It refers to
the 'regex' module of Python 1.4b1, which was subsequently replaced by
the current 're' module and then removed from the standard library. I
hope it's been updated since then. :-)


From loic.domaigne at googlemail.com  Thu Jul 30 17:41:50 2009
From: loic.domaigne at googlemail.com (=?ISO-8859-1?Q?Lo=EFc_Domaign=E9?=)
Date: Thu, 30 Jul 2009 14:41:50 -0700 (PDT)
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
Message-ID: <3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>

Hi,

> Hello. I have written a Python 3.1 script running on Windows that uses
> os.path.exists() to connect to network shares. If the various network
> shares require different user account and password combos than the
> account the script is running under the routine returns false. I need
> something like os.samba.path.exists(username,password,path). Does
> anyone have a suggestion on how I can accomplish what I need to do in
> Python?

Could the Python Samba module PySamba be interesting for you?
http://sourceforge.net/projects/pysamba/

HTH,
Lo?c
--
My blog: http://www.domaigne.com/blog


From python at mrabarnett.plus.com  Thu Jul 30 17:44:31 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 22:44:31 +0100
Subject: New implementation of re module
In-Reply-To: <200907301524.28703.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<4A719880.3070300@mrabarnett.plus.com>	<200907301518.28122.wolfgang@rohdewald.de>
	<200907301524.28703.wolfgang@rohdewald.de>
Message-ID: <4A72143F.6070506@mrabarnett.plus.com>

Wolfgang Rohdewald wrote:
> On Thursday 30 July 2009, Wolfgang Rohdewald wrote:
>> so I did the conversion mentioned there. This works:
> 
> I actually do not know if it works - but it compiles.
> 
Yes, it works. I've updated my code accordingly and it'll be in the next
release.


From rt8396 at gmail.com  Thu Jul 30 17:44:34 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 14:44:34 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
Message-ID: <23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>

On Jul 30, 4:29?pm, Emmanuel Surleau <emmanuel.surl... at gmail.com>
wrote:
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> It has benefits - code does look better. It has also significant cons - it is
> ambiguous.
> For instance:
>
> a = b
>
> Is b a variable or a method called without parameter?

Hello Emanuel,
Again, who so ever names a method with such a non-descriptive name
will get whats coming to him. And if you did for some reason use such
a cryptic name as "b", do yourself (and everyone else) a favor and
follow it with "()" to denote the method call. Remember when something
is optional that means you have an option to use it OR not use it.

optional (http://definr.com/optional)
  adj: possible but not necessary; left to personal choice [ant:
obligatory]


simple solutions for simple problems.


From zuo at chopin.edu.pl  Thu Jul 30 17:52:45 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 23:52:45 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
Message-ID: <op.uxwhp7jufvx12t@jerzozwiesz.home.aster.pl>

Dnia 30-07-2009 o 22:41:57 Masklinn <masklinn at masklinn.net> napisa?(a):

> On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
>> 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
>>
>>> On 30 Jul 2009, at 06:04 , alex23 wrote:
>>>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>>>> 2.) the .each method
>>>>> container.each{|localVar| block}
>>>>> This method can really cleanup some ugly for loops, although i really
>>>>> like the readability of for loops.
>>>>
>>>> map(lambda localVar: <block>, sequence)
>>>>
>>>> or:
>>>>
>>>> def usefully_named_func(var):
>>>>   <block>
>>>>   return var
>>>>
>>>> transformed = [usefully_named_func(v) for v in sequence]
>>>>
>>> The issue here is of course that `map` and comprehensions are  
>>> transformations. `#each` exists for effectful iterations (Ruby has  
>>> `#map` for the map operation). So the intent expressed by `#each` and  
>>> `map` isn't the same. Furthermore and this is the most problematic  
>>> limitation of Python here, `lambda` doesn't allow complex  
>>> transformations due to its restrictions, so one has to switch to named  
>>> functions which works but isn't sexy (and tends to lower readability  
>>> imo).
>>
>> I don't see any real limitation. What's wrong in:
>>
>> for localVar in container:
>>    block
>>
> Well what's wrong with using that rather than `map`, `filter` or a list  
> comprehension? (and if you don't see what the limitations of `lambda`  
> are, you probably very rarely use it)

I know well about the expression-only-limitation of lambda, fortnately
there is the 'for' loop construct (or, alternatively, you can define
a named function).

And then, what's wrong with using 'for' rather than 'map', 'filter' etc.?
Agree, that 'anonymous block syntax' would be nice in some cases, but
I don't see any real limitation caused by lack of it i.e. something you
can't (all you can only with unreasonable effort).

>> And ruby's container.each is very similar to Python's iter()

> Uh? not at all?

OK, .each is like Python's iter() + some form of iterating over it
('for' loop or '[i]map'...).

Still, in this matter there is no real functionality in Ruby that you
can't reach in Python.

All that confessions of a (former?) Python fanboy are about sintactic
sugars, which importance is incomparable which such issues as e.g.
particular mechanism of classes, their inheritance etc. or even such
small helpers like function annotations.

Cheers,

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From kyrie at uh.cu  Thu Jul 30 17:57:48 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Thu, 30 Jul 2009 17:57:48 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
Message-ID: <200907301757.48761.kyrie@uh.cu>

On Thursday 30 July 2009 04:41:57 pm Masklinn wrote:
> On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
> > 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
> >
> > I don't see any real limitation. What's wrong in:
> >
> > for localVar in container:
> >    block
>
> Well what's wrong with using that rather than `map`, `filter` or a
> list comprehension?

As I understood the question, it was "was wrong in 'for var in container' in 
comparison with ruby's container.each?"

What's the (semantic) difference between

for localVar in container:
    block

and

container.each{|localVar| block}

?

(the sintactic difference is quite clear... if there is no semantic 
difference, I'd rather use the first version!)

Map, filter and comprehensions have little to do with that (syntactic sugar 
that may allow some optimizations, but that could otherwise be replaced by 
the for loop).

> (and if you don't see what the limitations of 
> `lambda` are, you probably very rarely use it)

I'm not the poster, but: 
* I use lambdas, a lot.
* I "know" python lambdas are limited, compared with theoretical lambdas.
* I don't [usually] see that as a "limitation".

Most of the time, the limitation is the lack of multiline/multiexpression 
lambdas. But I've never seen a case where I would /prefer/ to have a 
multiline function definition inside a comprehension or method invocation, 
instead of a named function defined two lines before it.

(The second famous limitation is the inability to use statements inside 
lambdas... luckily, now that we have a ternary operator and a print function, 
it is less limiting)

> > And ruby's container.each is very similar to Python's iter()
>
> Uh? not at all?

I agree with this. It should have said that they are equivalent in the sense 
that they represent the iterator protocols of both languages, and nothing 
more.

I'd like to ask, what "container.each" is, exactly? It looks like a function 
call (as I've learned a few posts ago), but, what are its arguments? How the 
looping "works"? Does it receive a "code" object that it has to execute? 
Is .each some kind of magic keyword? (This has little to do with python or 
the current thread, so feel free to reply off-list if you want to...)

Regards,

Luis.

-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From python at mrabarnett.plus.com  Thu Jul 30 18:06:05 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 23:06:05 +0100
Subject: New implementation of re module
In-Reply-To: <m21vnye1d4.fsf@cs.uu.nl>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<m21vnye1d4.fsf@cs.uu.nl>
Message-ID: <4A72194D.4050604@mrabarnett.plus.com>

Piet van Oostrum wrote:
>>>>>> MRAB <python at mrabarnett.plus.com> (M) wrote:
> 
>> M> Hi all,
>> M> I've been working on a new implementation of the re module. The details
>> M> are at http://bugs.python.org/issue2636, specifically from
>> M> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>> M> Python 2.6 on Windows if you want to try it out.
> 
>> M> I'm interested in how fast it is generally, compared with the current re
>> M> module, but especially when faced with those 'pathological' regular
>> M> expressions which seem to take a long time to finish, for example:
> 
>> M>     re.search(r"^(.+|D)*A$", "x" * 25 + "B")
> 
>> M> which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs
>> M> with this new implementation.
> 
> Is this version also going to use the Thompson approach?

That approach is what inspired the method in the new implementation, but
its speed comes from asking _whether_ there's a match, not _where_
there's a match, so it can ignore the route taken to get the match.

"grep", for example, selects those lines which match a pattern, whereas
the typical Python (and Perl) usage is to extract part of a string or
which part of the string matches.

Trying to support lazy and possessive quantifiers in Thompson's approach
is tricky (at least, I haven't been able to figure it out), and
back-references are right out! :-)

There's always the chance that I could come up with some sort of hybrid
scheme, applying different approaches depending on certain conditions.
It already switches from depth-first to breadth-first when it's taken
too many iterations without advancing and merges similar states, which
is why it's so much better with 'pathological' patterns; I just have to
get the depth-first phase to be as fast as the current 're' module.


From benjamin.kaplan at case.edu  Thu Jul 30 18:08:21 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Thu, 30 Jul 2009 18:08:21 -0400
Subject: calling obect method
In-Reply-To: <960855.56660.qm@web7906.mail.in.yahoo.com>
References: <960855.56660.qm@web7906.mail.in.yahoo.com>
Message-ID: <ec96e1390907301508m4b98a60bm3af3b2bee234e79e@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:04 PM, srinivasan srinivas <
sri_annauni at yahoo.co.in> wrote:

> Hi,
> I would like to know if i have an object and one of its methods as a
> string. How to call the method using this string?
> For ex
> If object is x and string y has one of its method names.
> x.value(y)() ---. Is there a way to do this?
>
> Thanks,
> Srini



getattr(x,y)()

>
>
>
>      See the Web's breaking stories, chosen by people like you. Check out
> Yahoo! Buzz. http://in.buzz.yahoo.com/
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/fa5a0b18/attachment.html>

From rt8396 at gmail.com  Thu Jul 30 18:13:41 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 15:13:41 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net> 
	<mailman.4003.1248991082.8015.python-list@python.org>
Message-ID: <80839e72-9df4-4590-b22d-4c5c829e37b6@h11g2000yqb.googlegroups.com>

On Jul 30, 4:57?pm, Luis Zarrabeitia <ky... at uh.cu> wrote:
[snip]
> I'd like to ask, what "container.each" is, exactly? It looks like a function
> call (as I've learned a few posts ago), but, what are its arguments? How the
> looping "works"? Does it receive a "code" object that it has to execute?
> Is .each some kind of magic keyword? (This has little to do with python or
> the current thread, so feel free to reply off-list if you want to...)
>
> Regards,
>
> Luis.

Hello Luis,

I think your question is completely valid within the context of this
thread. The purpose of his thread was to get feedback on how Python
and Ruby ideas could be cumulated into the best high level language.
And being that i am the BDFL of the "Confessions of a Python Fanboy"
thread, you have my personal permission to continue on with this
subject matter...,



From rcdailey at gmail.com  Thu Jul 30 18:40:37 2009
From: rcdailey at gmail.com (Robert Dailey)
Date: Thu, 30 Jul 2009 15:40:37 -0700 (PDT)
Subject: Printing with colors in a portable way
Message-ID: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>

Anyone know of a way to print text in Python 3.1 with colors in a
portable way? In other words, I should be able to do something like
this:

print_color( "This is my text", COLOR_BLUE )

And this should be portable (i.e. it should work on Linux, Mac,
Windows).


From nyamatongwe+thunder at gmail.com  Thu Jul 30 18:47:35 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Thu, 30 Jul 2009 22:47:35 GMT
Subject: No PyPI search for 3.x compatible packages
In-Reply-To: <d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
	<d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
Message-ID: <bqpcm.8332$ze1.7277@news-server.bigpond.net.au>

Francesco Bochicchio :

> Are you sure? I note that for example pygtk has as language tags both
> C and python. So maybe a C extension
> for python3 would have both C and python 3 as language tags.
> 
> I suspect that the 109 packages you found are the only ones obf the
> 4829 which works with python3 (but I hope
> to be wrong ).

   There are 523 packages marked with Python :: [2, 2.1, ...] and I hope
more than that work with Python 2.x.

   What I would like to encourages is adding Python :: 3 or a more
specific minimum supported version classifier to packages that support
Python 3. I wouldn't want to go to the level of adding a classifier for
each version of Python supported since a package will often stay valid
when a new Python is released.

   Neil


From gdamjan at gmail.com  Thu Jul 30 18:59:31 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Fri, 31 Jul 2009 00:59:31 +0200
Subject: [ANN] pyKook 0.0.2 - a simple build tool similar to Make or Ant
References: <c0c0453c-c4ca-47a3-bf76-d2b7e2fad7ff@b25g2000prb.googlegroups.com>
Message-ID: <l7l9k6-st.ln1@archaeopteryx.softver.org.mk>

> I have released pyKook 0.0.2.
> http://pypi.python.org/pypi/Kook/0.0.2
> http://www.kuwata-lab.com/kook/
> http://www.kuwata-lab.com/kook/pykook-users-guide.html

How does it compare to http://code.google.com/p/fabricate/

and why is this problem (solution) reoccurring all the time


-- 
?????? ( http://softver.org.mk/damjan/ )

Teaching a pig to sing wastes your time & annoys the pig.



From robert.kern at gmail.com  Thu Jul 30 19:06:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 30 Jul 2009 18:06:31 -0500
Subject: Confessions of a Python fanboy
In-Reply-To: <23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
Message-ID: <h4t91n$obg$1@ger.gmane.org>

On 2009-07-30 16:44, r wrote:
> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com>
> wrote:
>>> 1.) No need to use "()" to call a function with no arguments.
>>> Python -->  "obj.m2().m3()" --ugly
>>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
>>> Man, i must admit i really like this, and your code will look so much
>>> cleaner.
>> It has benefits - code does look better. It has also significant cons - it is
>> ambiguous.
>> For instance:
>>
>> a = b
>>
>> Is b a variable or a method called without parameter?
>
> Hello Emanuel,
> Again, who so ever names a method with such a non-descriptive name
> will get whats coming to him. And if you did for some reason use such
> a cryptic name as "b", do yourself (and everyone else) a favor and
> follow it with "()" to denote the method call. Remember when something
> is optional that means you have an option to use it OR not use it.

I believe his point is that it is ambiguous to the compiler, not humans reading 
the code. Python functions and methods are first class objects. They can be 
passed around. If they were auto-called, then you could not do this.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From rhodri at wildebst.demon.co.uk  Thu Jul 30 19:29:50 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 31 Jul 2009 00:29:50 +0100
Subject: Printing with colors in a portable way
In-Reply-To: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
Message-ID: <op.uxwl70c1a8ncjz@gnudebst>

On Thu, 30 Jul 2009 23:40:37 +0100, Robert Dailey <rcdailey at gmail.com>  
wrote:

> Anyone know of a way to print text in Python 3.1 with colors in a
> portable way? In other words, I should be able to do something like
> this:
>
> print_color( "This is my text", COLOR_BLUE )
>
> And this should be portable (i.e. it should work on Linux, Mac,
> Windows).

...in an xterm, over a telnet connection, via VNC...

There's no portable way of doing this in any language, since it's
up to the terminal emulator exactly what it does with what incoming
bytes.  Some respect the ANSI colour codes, some don't; that's about
all that you can say.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From zuo at chopin.edu.pl  Thu Jul 30 19:54:20 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Fri, 31 Jul 2009 01:54:20 +0200
Subject: Printing with colors in a portable way
In-Reply-To: <op.uxwl70c1a8ncjz@gnudebst>
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
	<op.uxwl70c1a8ncjz@gnudebst>
Message-ID: <op.uxwncuztfvx12t@jerzozwiesz.home.aster.pl>

31-07-2009 o 01:29:50 Rhodri James <rhodri at wildebst.demon.co.uk> wrote:

> On Thu, 30 Jul 2009 23:40:37 +0100, Robert Dailey <rcdailey at gmail.com>  
> wrote:
>
>> Anyone know of a way to print text in Python 3.1 with colors in a
>> portable way? In other words, I should be able to do something like
>> this:
>>
>> print_color( "This is my text", COLOR_BLUE )
>>
>> And this should be portable (i.e. it should work on Linux, Mac,
>> Windows).
>
> ...in an xterm, over a telnet connection, via VNC...
>
> There's no portable way of doing this in any language, since it's
> up to the terminal emulator exactly what it does with what incoming
> bytes.  Some respect the ANSI colour codes, some don't; that's about
> all that you can say.

Yeah. Although you could try to provide "term-sensitive" mapping
of colour names -> codes, e.g.:

# color_codes.py

class NoColors:
     blue = ''
     red = ''

class XtermColors:
     blue = '<a code here>'
     red = '<a code here>'

class FooBarColors:
     blue = '<a code here>'
     red = '<a code here>'

COLORS = {
     'nocolors': NoColors,
     'xterm': XtermColors,
     'another term': FooBarColors,
}


# a_program.py

import color_codes

# e.g. with used_term == 'xterm'...
colors = color_codes.COLORS[used_term]

print('Some text, {colors.blue}Something in blue, '
       '{colors.red}And now in red.').format(colors=colors)


Regards,
*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From gagsl-py2 at yahoo.com.ar  Thu Jul 30 20:04:01 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 30 Jul 2009 21:04:01 -0300
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
	<mailman.3970.1248966648.8015.python-list@python.org>
	<27mdnb-NxM3DJOzXnZ2dnUVZ_hxi4p2d@posted.visi>
Message-ID: <op.uxwnszkpx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 30 Jul 2009 12:16:46 -0300, Unknown <unknown at unknown.invalid>  
escribi?:
> On 2009-07-30, Barak, Ron <Ron.Barak at lsi.com> wrote:

>> On second thoughts, I may have a problem implementing the
>> wrapper solution, because my actual test_pyc.pyc, needs to
>> parse its command line. Namely, the actual call to
>> test_pyc.pyc looks something like this:
>>
>> $ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume  
>> --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t  
>> tvn -p pool1 -l -c
>>
>> And I don't know of a way to add these parameters to the
>> "import test_pyc" in wrapper
>>
>> Is there a way to pass information to an imported module ?
>> (Sorry if there's an obvious answer, I just cannot figure it
>> out).
>
> I don't understand your problem.  The module would parse
> sys.argv just like always.
>
> If you don't like that for some reason, you could define an
> entry point in the module and call it:
>
> #!/usr/bin/python
> import sys,test_pyc
> test_pyc.main(*sys.argv)

And you *should* do it that way, instead of just importing the other  
module and executing ALL the program as a side-effect of the import  
statement. In the first case, the import lock will prevent other threads  
to run.

-- 
Gabriel Genellina



From digitig at gmail.com  Thu Jul 30 20:05:29 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 31 Jul 2009 01:05:29 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e1a5$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<4a71e1a5$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <aee48b3c0907301705p3b34e561rb77752297eec7125@mail.gmail.com>

2009/7/30 superpollo <user at example.net>:
> Tim Rowe wrote:

>> Any language that gets any sort of real use has to have. For instance,
>> I love Ada's numeric types (you can specify either the minimum number
>> of significant figures or the maximum delta for a real type, and it
>> will give you a type that satisfies that -- or a compilation error if
>> it can't. ?That matches genuine problem domains far better
>
> doesn't the decimal module do some of that too?

Not as far as I can tell, no.

-- 
Tim Rowe


From j.sundo at cs.ucl.ac.uk  Thu Jul 30 20:17:04 2009
From: j.sundo at cs.ucl.ac.uk (=?ISO-8859-1?Q?Jannik_Sund=F8?=)
Date: Fri, 31 Jul 2009 01:17:04 +0100
Subject: Confused About Python Loggin
Message-ID: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>

Dear all, I am quite confused about the Python logging. I have read  
and re-read the Python documentation for the Python logging module and  
googled, but to no avail. I simply want one logger to log to a file  
and another logger to log to the console. Neither should log the  
other's messages. The code below causes fileLogger to log to BOTH a  
file and the console, how come? It seems to me that a call such as  
"consoleHandler = logging.StreamHandler()" affects other loggers,  
which I do not want. Also, if I do not do  
logging.basicConfig(level=logging.INFO) in one of the classes of my  
application, the logging does not work. Any ideas how come?

Thanks a lot for any help! :)

fileHandler = logging.FileHandler('../../logs/log.txt')
fileLogger = logging.getLogger('TESTHARNESSFILE')
fileLogger.addHandler(fileHandler)
fileLogger.setLevel(logging.INFO)
consoleHandler = logging.StreamHandler()
logger = logging.getLogger('TESTHARNESS')
logger.addHandler(consoleHandler)
logger.setLevel(logging.INFO)


From dhaneshpai at gmail.com  Thu Jul 30 20:24:10 2009
From: dhaneshpai at gmail.com (Dhanesh)
Date: Thu, 30 Jul 2009 17:24:10 -0700 (PDT)
Subject: Non-blocking read with popen subprocess
Message-ID: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>

Hi ,

I am trying to use subprocess popen on a windows command line
executable with spits messages on STDOUT as well as STDIN. Code
snippet is as below :-
##########################################################################
sOut=""
    sErr=""
    javaLoaderPath = os.path.join("c:\\","Program Files","Research In
Motion","BlackBerry JDE 4.7.0","bin","Javaloader.exe")
    cmd = [javaLoaderPath,'-u','load','helloworld.jad']
    popen = subprocess.Popen
(cmd,bufsize=256,shell=False,stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
    while True:
        sErr = sErr + popen.stderr.read(64)
        sOut = sOut + popen.stdout.read(64)------------------> Blocks
here
        if None != popen.poll():
            break;
##########################################################################

I observed that python scripts blocks at stdout read on the other hand
when I do not create a child stdout PIPE  say  " stdout=None" , things
seems to be working fine.

how can I we have a non blocking read ?
And why does stdout block even where data is available to be read
( which seem to be apparent when stdout=None, and logs appear on
parents STDOUT) ?



From tjreedy at udel.edu  Thu Jul 30 20:38:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 20:38:15 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <39013d06-e281-4459-bdb2-19831c9526ea@k1g2000yqf.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>	<mailman.3995.1248987328.8015.python-list@python.org>
	<39013d06-e281-4459-bdb2-19831c9526ea@k1g2000yqf.googlegroups.com>
Message-ID: <h4tedl$4c4$1@ger.gmane.org>

r wrote:
> On Jul 30, 3:55 pm, Terry Reedy <tjre... at udel.edu> wrote:
>> superpollo wrote:
>>> r wrote:
>>> how to reverse a string in python? must i usa a temp? like:
> [snip]
>> Terry Jan Reedy
> 
> No "r" never wrote anything like that. reversing a string is RTFM
> material, this is basic stuff here! Stop quoting me as saying things i
> did not say! I never asked how to reverse a string, "superpollo"
> did.

Nor did what I posted say that you did. The above says that superpollo 
wrote "how to reverse..., as he did. Quotes are indented once more than 
the author. The above says 'r wrote' with no indent and then "No...", 
which you did write, indented once.

I agree that since I did not quote anything that you wrote, I should 
also have snipped your name. But I least I do attempt to snip material 
irrelavant to my comments.

Terry Jan Reedy



From brochu121 at gmail.com  Thu Jul 30 20:57:56 2009
From: brochu121 at gmail.com (David Brochu)
Date: Thu, 30 Jul 2009 20:57:56 -0400
Subject: httplib headers
Message-ID: <9583ed900907301757q50e85b42o830820980386ff57@mail.gmail.com>

Using the following code I am trying to pass a header to my POST request.
(Note: urls masked)

file = sys.argv[0]
url = sys.argv[1]
conn = httplib.HTTPConnection("XX.XXX.XX.XXX",XXXX)
headers = {'content-type':'application/xml'}
conn.request("POST",url,file,headers)
response = conn.getresponse()
head = response.getheaders()
status = response.status
response = response.read()
print response, status, head

When I run this script and view the headers that get printed the following
displays:

[('content-length', '691'), ('proxy-connection', 'Keep-Alive'),
('connection', 'Keep-Alive'), ('pragma', 'no-cache'), ('cache-control',
'no-cache'), ('content-type', 'text/html; charset=utf-8')]
Why isn't my content-type header using the value I pass in from headers?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/99e547a7/attachment.html>

From aahz at pythoncraft.com  Thu Jul 30 21:13:53 2009
From: aahz at pythoncraft.com (Aahz)
Date: 30 Jul 2009 18:13:53 -0700
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
	<mailman.3949.1248951463.8015.python-list@python.org>
Message-ID: <h4tggh$6rt$1@panix3.panix.com>

In article <mailman.3949.1248951463.8015.python-list at python.org>,
Chris Rebert  <clp2 at rebertia.com> wrote:
>
>No, with the shebang line (and assuming execute permissions on the
>file), it would look like:
>
>./wrapper.py

There's no reason to name it ".py"; you can have a perfectly useful
"shell script" that just happens to list python on the shebang line
instead of the usual /bin/sh.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From python at mrabarnett.plus.com  Thu Jul 30 21:20:40 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 02:20:40 +0100
Subject: httplib headers
In-Reply-To: <9583ed900907301757q50e85b42o830820980386ff57@mail.gmail.com>
References: <9583ed900907301757q50e85b42o830820980386ff57@mail.gmail.com>
Message-ID: <4A7246E8.3010400@mrabarnett.plus.com>

David Brochu wrote:
> Using the following code I am trying to pass a header to my POST 
> request. (Note: urls masked)
>  
> file = sys.argv[0]
> url = sys.argv[1]
> conn = httplib.HTTPConnection("XX.XXX.XX.XXX",XXXX)
> headers = {'content-type':'application/xml'}
> conn.request("POST",url,file,headers)
> response = conn.getresponse()
> head = response.getheaders()
> status = response.status
> response = response.read()
> print response, status, head
>  
> When I run this script and view the headers that get printed the 
> following displays:
>  
> [('content-length', '691'), ('proxy-connection', 'Keep-Alive'), 
> ('connection', 'Keep-Alive'), ('pragma', 'no-cache'), ('cache-control', 
> 'no-cache'), ('content-type', 'text/html; charset=utf-8')]
> Why isn't my content-type header using the value I pass in from headers?
> 
Aren't you just setting the headers for the "POST" you're sending
(you're posting a file whose content type is 'application/xml'), but
printing the headers of the response you receive (the content type of
the response is 'text/html; charset=utf-8')?


From jgardner at jonathangardner.net  Thu Jul 30 22:30:46 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Thu, 30 Jul 2009 19:30:46 -0700 (PDT)
Subject: Non-blocking read with popen subprocess
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
Message-ID: <824f8092-55b1-4df2-a6b5-74a4b1b1d9ea@i18g2000pro.googlegroups.com>

On Jul 30, 5:24?pm, Dhanesh <dhanesh... at gmail.com> wrote:
>
> how can I we have a non blocking read ?

See http://docs.python.org/library/popen2.html#flow-control-issues

Note well: In the non-blocking world, you have to use select() or poll
() to get your job done.

You may want to look at "communicate" (http://docs.python.org/library/
subprocess.html#popen-objects) which may be what you need.


From lukepadawan at gmail.com  Thu Jul 30 22:55:40 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Thu, 30 Jul 2009 23:55:40 -0300
Subject: Generators through the C API
Message-ID: <4A725D2C.4030705@gmail.com>

Hello, I'm a total noob about the C API. Is there any way to create a 
generator function using the C API? I couldn't find anything like the 
'yield' keyword in it.

Thanks in advance.


From grante at visi.com  Thu Jul 30 23:02:17 2009
From: grante at visi.com (Grant Edwards)
Date: Thu, 30 Jul 2009 22:02:17 -0500
Subject: Printing with colors in a portable way
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
Message-ID: <cfydnSlcPuYkw-_XnZ2dnUVZ_rCdnZ2d@posted.usinternet>

On 2009-07-30, Robert Dailey <rcdailey at gmail.com> wrote:
> Anyone know of a way to print text in Python 3.1 with colors in a
> portable way? In other words, I should be able to do something like
> this:
>
> print_color( "This is my text", COLOR_BLUE )
>
> And this should be portable (i.e. it should work on Linux, Mac,
> Windows).

Generating postscript or PDF is the only remotely portable way
to print anything.

-- 
Grant



From cocobear.cn at gmail.com  Fri Jul 31 00:18:25 2009
From: cocobear.cn at gmail.com (cocobear)
Date: Thu, 30 Jul 2009 21:18:25 -0700 (PDT)
Subject: merge two png pic
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
Message-ID: <b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>

On Jul 29, 9:20?am, cocobear <cocobear... at gmail.com> wrote:
> Thistwopngfile has their own palette
>
> >>> im1.mode
> 'P'
> >>> im.mode
> 'P'
> >>> im.getpalette == im1.getpalette
>
> False
>
> I can use this code tomergetwopngpictogether:
>
> Map = Image.new("RGB", (x,y))
> Map.paste(im, box)
> Map.paste(im1,box)
>
> Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)
>
> But if thetwopngpicis too big , or if I have tomergemorepic
> together, I will get MemoryError:
>
> >>> Image.new("RGB",(44544,38656))
>
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> ? File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
> new
> ? ? return Image()._new(core.fill(mode, size, color))
> MemoryError
>
> How can I directlymergetwopicto a ?P' modepngwith palette.


Nobody replied.


From ivlenin at gmail.com  Fri Jul 31 01:27:22 2009
From: ivlenin at gmail.com (I V)
Date: 31 Jul 2009 07:27:22 +0200
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<mailman.4003.1248991082.8015.python-list@python.org>
Message-ID: <4a7280ba$1@news.x-privat.org>

On Thu, 30 Jul 2009 17:57:48 -0400, Luis Zarrabeitia wrote:
> As I understood the question, it was "was wrong in 'for var in
> container' in comparison with ruby's container.each?"
> 
> What's the (semantic) difference between
> 
> for localVar in container:
>     block
> 
> and
> 
> container.each{|localVar| block}

I don't think "each" is a particularly compelling example of Ruby's 
blocks - as you say, it's easily replaceable with a Python for-loop. The 
advantage of Ruby's syntax is that it allows you to define further 
functions that are sort-of like new control structures. So you have 
things like:

File.open('myfile', 'r') do |file|
	while line = file.gets
		puts line
	end
end

Which is like a python's:

with open('myfile', 'r) as f:
	for line in f:
		print f

However, with Ruby, this kind of scoping construct can be added without 
adding new syntax. Another interesting example is the Sinatra web 
framework, which allows you to write a web app with something like:

get '/' do
	"Index page"
end

post '/:name' do 
	"Posted to " + params[:name]
end

Which looks something like a DSL for web apps, but is accomplished solely 
with normal ruby functions. More: http://www.sinatrarb.com/intro.html

Ruby blocks are, fundamentally, syntactic sugar, but they are kind of 
neat.


From emmanuel.surleau at gmail.com  Fri Jul 31 01:46:49 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 07:46:49 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <h4t91n$obg$1@ger.gmane.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<h4t91n$obg$1@ger.gmane.org>
Message-ID: <200907310746.49392.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 01:06:31 Robert Kern wrote:
> On 2009-07-30 16:44, r wrote:
> > On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com>
> >
> > wrote:
> >>> 1.) No need to use "()" to call a function with no arguments.
> >>> Python -->  "obj.m2().m3()" --ugly
> >>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
> >>> Man, i must admit i really like this, and your code will look so much
> >>> cleaner.
> >>
> >> It has benefits - code does look better. It has also significant cons -
> >> it is ambiguous.
> >> For instance:
> >>
> >> a = b
> >>
> >> Is b a variable or a method called without parameter?
> >
> > Hello Emanuel,
> > Again, who so ever names a method with such a non-descriptive name
> > will get whats coming to him. And if you did for some reason use such
> > a cryptic name as "b", do yourself (and everyone else) a favor and
> > follow it with "()" to denote the method call. Remember when something
> > is optional that means you have an option to use it OR not use it.
>
> I believe his point is that it is ambiguous to the compiler, not humans
> reading the code.

Actually, both. Use a variable you didn't initialize? This is what you get:

NameError: undefined local variable or method `b' for main:Object
        from (irb):1

The compiler has no idea if b is a variable or a method. It also makes it very 
easy to shadow an existing method by declaring a variable of the same name, 
which is problematic. I suppose it is a side-effect of Ruby's Perl 
philosophical inheritance - except that Perl uses sigils to prefix its 
variables, negating this issue.

Cheers,

Emm


From steve at nospam.au  Fri Jul 31 02:09:48 2009
From: steve at nospam.au (steve)
Date: Fri, 31 Jul 2009 16:09:48 +1000
Subject: Test for Pythonwin?
Message-ID: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>

Is there a good way to check if a script is running inside Pythonwin?
Perhaps a property or method that is exposed by that environment?

or, alternatively, is there a better place to ask :-)

Steven 




From __peter__ at web.de  Fri Jul 31 02:52:01 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 08:52:01 +0200
Subject: merge two png pic
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
	<b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>
Message-ID: <h4u4al$qtm$02$1@news.t-online.com>

cocobear wrote:

> On Jul 29, 9:20 am, cocobear <cocobear... at gmail.com> wrote:
>> Thistwopngfile has their own palette
>>
>> >>> im1.mode
>> 'P'
>> >>> im.mode
>> 'P'
>> >>> im.getpalette == im1.getpalette
>>
>> False
>>
>> I can use this code tomergetwopngpictogether:
>>
>> Map = Image.new("RGB", (x,y))
>> Map.paste(im, box)
>> Map.paste(im1,box)
>>
>> Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)
>>
>> But if thetwopngpicis too big , or if I have tomergemorepic
>> together, I will get MemoryError:
>>
>> >>> Image.new("RGB",(44544,38656))

As a workaround you could split the image into tiles that fit into your 
machine's RAM. Or you could try to do the rendering on a 64-bit system. 
You'll need at least

>>> 3*44544*38656./(2**30)
4.8109130859375

5 gigabytes for the target image plus memory for the biggest source image. 
Alternatively there are probably tools that can keep parts of the image on 
disk (imagemagick, maybe? you'll have to check yourself or ask in a 
specialized forum). As a last resort you should be able to write such a tool 
yourself. I don't know how hard it would be to generate the PNG, but the RGB 
pasting should be trivial.

>> Traceback (most recent call last):
>> File "<stdin>", line 1, in <module>
>> File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
>> new
>> return Image()._new(core.fill(mode, size, color))
>> MemoryError
>>
>> How can I directlymergetwopicto a ?P' modepngwith palette.
> 
> 
> Nobody replied.

What do you want to do with such a big image? You will run into the same 
limitation when you are trying to display it.

Peter



From tjreedy at udel.edu  Fri Jul 31 02:52:56 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 02:52:56 -0400
Subject: merge two png pic
In-Reply-To: <b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
	<b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>
Message-ID: <h4u4c5$dsp$1@ger.gmane.org>

cocobear wrote:
> On Jul 29, 9:20 am, cocobear <cocobear... at gmail.com> wrote:
>> Thistwopngfile has their own palette
>>
>>>>> im1.mode
>> 'P'
>>>>> im.mode
>> 'P'
>>>>> im.getpalette == im1.getpalette
>> False
>>
>> I can use this code tomergetwopngpictogether:
>>
>> Map = Image.new("RGB", (x,y))
>> Map.paste(im, box)
>> Map.paste(im1,box)
>>
>> Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)
>>
>> But if thetwopngpicis too big , or if I have tomergemorepic
>> together, I will get MemoryError:
>>
>>>>> Image.new("RGB",(44544,38656))
>> Traceback (most recent call last):
>>   File "<stdin>", line 1, in <module>
>>   File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
>> new
>>     return Image()._new(core.fill(mode, size, color))
>> MemoryError
>>
>> How can I directlymergetwopicto a ?P' modepngwith palette.
> 
> 
> Nobody replied.

A. Leavingoutspacesmakesyourposthardtoread.

B. Nobody knows how to avoid mem error.

tjr




From shearichard at gmail.com  Fri Jul 31 03:09:48 2009
From: shearichard at gmail.com (northof40)
Date: Fri, 31 Jul 2009 00:09:48 -0700 (PDT)
Subject: Python 2.6 in shared/VPS environment
Message-ID: <6babf860-0161-4c1a-82f8-69e03dc53da0@p36g2000prn.googlegroups.com>

Hi - I'd really like to have access to Python 2.6 to try something
out. It needs to be on Linux/Unix machine. I don't mind paying but
whichever way I turn I find Python 2.4 is the standard installation.

Anyone know of anyone who offers this out of the box ? Or got any
smart way of achieving it ?

thanks

R.





From __peter__ at web.de  Fri Jul 31 03:14:59 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 09:14:59 +0200
Subject: Confused About Python Loggin
References: <mailman.4011.1249000497.8015.python-list@python.org>
Message-ID: <h4u5lf$24c$01$1@news.t-online.com>

Jannik Sund? wrote:

> Dear all, I am quite confused about the Python logging. I have read
> and re-read the Python documentation for the Python logging module and
> googled, but to no avail. I simply want one logger to log to a file
> and another logger to log to the console. Neither should log the
> other's messages. The code below causes fileLogger to log to BOTH a
> file and the console, how come? It seems to me that a call such as
> "consoleHandler = logging.StreamHandler()" affects other loggers,
> which I do not want. Also, if I do not do
> logging.basicConfig(level=logging.INFO) in one of the classes of my
> application, the logging does not work. Any ideas how come?
> 
> Thanks a lot for any help! :)
> 
> fileHandler = logging.FileHandler('../../logs/log.txt')
> fileLogger = logging.getLogger('TESTHARNESSFILE')
> fileLogger.addHandler(fileHandler)
> fileLogger.setLevel(logging.INFO)
> consoleHandler = logging.StreamHandler()
> logger = logging.getLogger('TESTHARNESS')
> logger.addHandler(consoleHandler)
> logger.setLevel(logging.INFO)

The code you present should work as you expect:

$ cat tmp.py
import logging

fileHandler = logging.FileHandler('tmp.txt')
fileLogger = logging.getLogger('TESTHARNESSFILE')
fileLogger.addHandler(fileHandler)
fileLogger.setLevel(logging.INFO)

consoleHandler = logging.StreamHandler()
logger = logging.getLogger('TESTHARNESS')
logger.addHandler(consoleHandler)
logger.setLevel(logging.INFO)


logger.info("to console")
fileLogger.info("to file")
$ python tmp.py
to console
$ cat tmp.txt
to file

What problems exactly are you running into if you omit the basicConfig() 
call?

Peter



From malc0de.encrypt at gmail.com  Fri Jul 31 03:25:09 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 00:25:09 -0700 (PDT)
Subject: problem on socket programming
Message-ID: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>

hello there, I'm using Learning Python 3rd edition as my core
reference, the book is great.
here's some snippet for demonstrating echo-server program, but I can't
interpret it in both windows / Gnu linux ...

#!/usr/bin/env python
from socket import *
myHost = ''
myPort = 50007
sockobj = socket(AF_INET,SOCK_STREAM)
sockobj.bind((myHost,myPort))
sockobj.listen(5)
while true :
    connection,address = sockobj.accept()
    print 'server connected by :',address
    while True:
        data = connection.recv(1024)
        if not data: break
        connection.send('echo : '+ data)
    connection.close()

where's the problem,
beforehand appreciate ...


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 03:28:29 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 07:28:29 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<mailman.4006.1248995212.8015.python-list@python.org>
Message-ID: <008e7846$0$9756$c3e8da3@news.astraweb.com>

On Thu, 30 Jul 2009 18:06:31 -0500, Robert Kern wrote:

> On 2009-07-30 16:44, r wrote:
>> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com> wrote:
>>>> 1.) No need to use "()" to call a function with no arguments. Python
>>>> -->  "obj.m2().m3()" --ugly
>>>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
>>>> Man, i must admit i really like this, and your code will look so much
>>>> cleaner.
>>> It has benefits - code does look better. It has also significant cons
>>> - it is ambiguous.
>>> For instance:
>>>
>>> a = b
>>>
>>> Is b a variable or a method called without parameter?
>>
>> Hello Emanuel,
>> Again, who so ever names a method with such a non-descriptive name will
>> get whats coming to him. And if you did for some reason use such a
>> cryptic name as "b", do yourself (and everyone else) a favor and follow
>> it with "()" to denote the method call. Remember when something is
>> optional that means you have an option to use it OR not use it.
> 
> I believe his point is that it is ambiguous to the compiler, not humans
> reading the code. Python functions and methods are first class objects.
> They can be passed around. If they were auto-called, then you could not
> do this.

Oh my, "r" is still around is he??? And now he's singing the praises of 
Ruby, the language which he treated as the Devil's Spawn when he first 
arrived. That's hilarious.

But back on topic... "r" has missed the point. It's not that a=b is hard 
to understand because b is a poor name. The example could have been:

def factory_function():
    magic = time.time()  # or whatever
    def inner():
        return magic
    return inner

my_function = factory_function

It's still ambiguous. Does the programmer intend my_function to become 
factory_function itself, or the output of factory_function?

In Python, it's not ambiguous at all -- my_function is set to 
factory_function, and *not* the output of factory_function, because you 
haven't called the function.

Python's model is consistent and simple: given a function "func", you 
*always* refer to the function object itself as func and you *always* 
call it with func(). This applies no matter how many arguments the 
function takes, or what it returns, or where it is defined.

I think it's telling that "r" the fanboy has rejected Python's advantages 
(simplicity, consistency, unambiguity) in favour of lazily saving two 
keystrokes.



-- 
Steven


From lkrzysiak at gmail.com  Fri Jul 31 03:28:54 2009
From: lkrzysiak at gmail.com (=?UTF-8?Q?=C5=81ukasz?=)
Date: Fri, 31 Jul 2009 00:28:54 -0700 (PDT)
Subject: How to force SAX parser to ignore encoding problems
Message-ID: <89c214a4-e846-4101-b0b3-8078eec15114@w41g2000yqb.googlegroups.com>

Hi,
I have a problem with my XML parser (created with libraries from
xml.sax package). When parser finds a invalid character (in CDATA
section) for example ?, throws an exception SAXParseException.

Is there any way to just ignore this kind of problem. Maybe there is a
way to set up parser in less strict mode?

I know that I can catch this exception and determine if this is this
kind of problem and then ignore this, but I am asking about any global
setting.



From contact at xavierho.com  Fri Jul 31 03:34:32 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 17:34:32 +1000
Subject: problem on socket programming
In-Reply-To: <2d56febf0907310033n66afa69ch3a43bcbe078396c5@mail.gmail.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<2d56febf0907310033n66afa69ch3a43bcbe078396c5@mail.gmail.com>
Message-ID: <2d56febf0907310034kf012f4br2b8ef56688e2883c@mail.gmail.com>

Whoops, posted to the wrong address.... yet again.

I deserve some punishment.

On Fri, Jul 31, 2009 at 5:33 PM, Xavier Ho <contact at xavierho.com> wrote:

> On Fri, Jul 31, 2009 at 5:25 PM, MalC0de <malc0de.encrypt at gmail.com>wrote:
>
>>
>> while true :
>>
>> where's the problem,
>
>
> There. =]
>

(Btw, it's True, not true.)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/169f94fb/attachment.html>

From efotinis at oohay.com  Fri Jul 31 03:38:41 2009
From: efotinis at oohay.com (eliasf)
Date: Fri, 31 Jul 2009 10:38:41 +0300
Subject: Test for Pythonwin?
In-Reply-To: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>
References: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>
Message-ID: <1249025993.67838@athprx04>

"steve" wrote:
> Is there a good way to check if a script is running inside Pythonwin?
> Perhaps a property or method that is exposed by that environment?

I don't know how foolproof it is, but this works:

    'pywin' in sys.modules



From piet at cs.uu.nl  Fri Jul 31 03:47:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 31 Jul 2009 09:47:34 +0200
Subject: Non-blocking read with popen subprocess
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
	<824f8092-55b1-4df2-a6b5-74a4b1b1d9ea@i18g2000pro.googlegroups.com>
Message-ID: <m2vdl9uwdl.fsf@cs.uu.nl>

>>>>> Jonathan Gardner <jgardner at jonathangardner.net> (JG) wrote:

>JG> On Jul 30, 5:24?pm, Dhanesh <dhanesh... at gmail.com> wrote:
>>> 
>>> how can I we have a non blocking read ?

>JG> See http://docs.python.org/library/popen2.html#flow-control-issues

>JG> Note well: In the non-blocking world, you have to use select() or poll
>JG> () to get your job done.

AFAIK, on Windows these work only on sockets, not on files. I think
pipes are in the files camp.

Alternatively you can read one of the two in a different thread.

>JG> You may want to look at "communicate" (http://docs.python.org/library/
>JG> subprocess.html#popen-objects) which may be what you need.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From masklinn at masklinn.net  Fri Jul 31 03:48:24 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 09:48:24 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <op.uxwhp7jufvx12t@jerzozwiesz.home.aster.pl>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<op.uxwhp7jufvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <27BA9FDF-8295-41F5-A4E7-170B0D755159@masklinn.net>

On 30 Jul 2009, at 23:52 , Jan Kaliszewski wrote:
> Dnia 30-07-2009 o 22:41:57 Masklinn <masklinn at masklinn.net>  
> napisa?(a):
> On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
>>> 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
>>>> On 30 Jul 2009, at 06:04 , alex23 wrote:
>>>>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>>>>> 2.) the .each method
>>>>>> container.each{|localVar| block}
>>>>>> This method can really cleanup some ugly for loops, although i  
>>>>>> really
>>>>>> like the readability of for loops.
>>>>>
>>>>> map(lambda localVar: <block>, sequence)
>>>>>
>>>>> or:
>>>>>
>>>>> def usefully_named_func(var):
>>>>>  <block>
>>>>>  return var
>>>>>
>>>>> transformed = [usefully_named_func(v) for v in sequence]
>>>>>
>>>> The issue here is of course that `map` and comprehensions are  
>>>> transformations. `#each` exists for effectful iterations (Ruby  
>>>> has `#map` for the map operation). So the intent expressed by  
>>>> `#each` and `map` isn't the same. Furthermore and this is the  
>>>> most problematic limitation of Python here, `lambda` doesn't  
>>>> allow complex transformations due to its restrictions, so one has  
>>>> to switch to named functions which works but isn't sexy (and  
>>>> tends to lower readability imo).
>>>
>>> I don't see any real limitation. What's wrong in:
>>>
>>> for localVar in container:
>>>   block
>>>
>> Well what's wrong with using that rather than `map`, `filter` or a  
>> list comprehension? (and if you don't see what the limitations of  
>> `lambda` are, you probably very rarely use it)
>
> I know well about the expression-only-limitation of lambda, fortnately
> there is the 'for' loop construct (or, alternatively, you can define
> a named function).
>
> And then, what's wrong with using 'for' rather than 'map', 'filter'  
> etc.?
Nothing, but then again nothing's wrong using C's for either.

But I do think that using higher-order functions:
* tends to be terser while not going overly terse, it only removes  
boilerplate
* is more composable (it's pretty easy to tack another transformer in  
your chain, the same way defining iterator/generator transformers and  
chaining them is simpler than doing the same thing using explicit  
`for?in`)
* it clearly spells the intent of the programmer, while `for` can be  
anything and everything, and one has to dive into the code to know  
even the high-level operations performed (is it a basic  
transformation? A filtering or partitioning? A reduction? An  
application of side effects?)
> Agree, that 'anonymous block syntax' would be nice in some cases, but
> I don't see any real limitation caused by lack of it i.e. something  
> you
> can't (all you can only with unreasonable effort).
>
There are no limitations, but once again there never are. There are no  
actual limitations to using conditional jumps over iterators either.

>>> And ruby's container.each is very similar to Python's iter()
>
>> Uh? not at all?
>
> OK, .each is like Python's iter() + some form of iterating over it
> ('for' loop or '[i]map'...).
Well of course Enumerable#each is similar to map/imap, it's the same  
core principle.

From malc0de.encrypt at gmail.com  Fri Jul 31 03:50:19 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 00:50:19 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
Message-ID: <3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>

problem with this code solved in win32, but I didn't test it after
solved problem on gnu/linux .


From bieffe62 at gmail.com  Fri Jul 31 03:51:45 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Fri, 31 Jul 2009 00:51:45 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com> 
	<mailman.3992.1248984980.8015.python-list@python.org>
Message-ID: <45056c13-9ff6-4a0f-b357-1893d7d03144@s15g2000yqs.googlegroups.com>

On Jul 30, 10:16?pm, "Jan Kaliszewski" <z... at chopin.edu.pl> wrote:
> 30-07-2009 o 12:29:24 Francesco Bochicchio <bieff... at gmail.com> wrote:
>
> > On Jul 30, 5:52?am, NighterNet <darkne... at gmail.com> wrote:
> >> I am trying to figure out how to send text or byte in python 3.1. I am
> >> trying to send data to flash socket to get there. I am not sure how to
> >> work it.
>
> >> buff= 'id=' , self.id , ':balive=False\n'
> >> clientSock.send(buff);
>
> > Try putting a 'b' before the constant string that you want to send:
>
> > >>> type(b'123')
> > <class 'bytes'>
>
> It's true. In python '...' literals are for strings ('str' type) and
> b'...' literals are for binary data (bytes type).
>
> Sockets' send() and recv() need binary data ('bytes' objects).
>
> > or use something like this to convert non constant strings (with only
> > ASCII characters) into bytes:
> > >>> s = "A non-constant string : %d " % n
> > >>> s
> > 'A non-constant string : 12 '
> > >>> type(s)
> > <class 'str'>
>
> What???
>
> 'str' type in Python 3.x IS NOT a type of "non-constant" strings and
> IS NOT a type of strings "with only ASCII characters"!
>
> 'str' type in Python 3.x *is* the type of immutable ('constant') and
> Unicode character (Unicode, not only ASCII) strings. It's the same what
> 'unicode' type in Python 2.x.
>

... unfortunate choice of words and not enough research on my part
here. WHat I meant was: if you want
to send via socket a constant string, use b"..."; if you want to send
via socket  a string that you
made out of variables (the "non-constant string" ) then you have to
convert it in bytes. Since I did not
now of the encode method, I tried other solutions, like the one-liner
using ord or using the struct
module. Obviously, encode is better.

My bad :-)

Ciao
-------
FB


From malc0de.encrypt at gmail.com  Fri Jul 31 04:02:33 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 01:02:33 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
Message-ID: <e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>

now I've been encountered to some errors with this snippet :

import sys
from socket import *
serverHost = 'localhost'
serverPort = 50007
message = ['Hello network world']
if len(sys.argv) > 1:
    serverHost = sys.argv[1]
    if len(sys.argv) > 2:
        message = sys.argv[2:]
sockobj = socket(AF_INET,SOCK_STREAM)
sockobj.connect((serverHost,serverPort))
for line in message:
    sockobj.send(line)
    data = sockobj.recv(1024)
    print 'Client recieved :',repr(data)
sockobj.close()


thanks if someone can solve my problem .

- malc0de.


From matt.urry at googlemail.com  Fri Jul 31 04:04:08 2009
From: matt.urry at googlemail.com (ma3mju)
Date: Fri, 31 Jul 2009 01:04:08 -0700 (PDT)
Subject: Processes not exiting
Message-ID: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>

Hi all,

I'm having trouble with multiprocessing I'm using it to speed up some
simulations, I find for large queues when the process reaches the
poison pill it does not exit whereas for smaller queues it works
without any problems. Has anyone else had this trouble? Can anyone
tell me a way around it? The code is in two files below.

Thanks

Matt

parallel.py
===================================================
import GaussianProcessRegression as GP
import numpy as np
import networkx as nx
import pickle
import multiprocessing
############################################################################################
# Things You Can Change
############################################################################################
#savefiles
savefile = "wattsdata2"
graphfile = "wattsgraphs2"
#sample sizes
num_graphs = 5
num_sets_of_data = 10
#other things...
intervals = np.ceil(np.logspace(-2,1,50)*500)
noise = [np.sqrt(0.1),np.sqrt(0.01),np.sqrt(0.001),np.sqrt(0.0001)]

############################################################################################
#generate graphs
graphs  = []
for i in range(0,num_graphs):
    graphs.append(nx.watts_strogatz_graph(500,5,0.01))
#save them for later reference
filehandler = open(graphfile,'w')
pickle.dump(graphs,filehandler,-1)
filehandler.close()

#queues
easy_work_queue = multiprocessing.Queue()
hard_work_queue = multiprocessing.Queue()
result_queue = multiprocessing.Queue()
#construct the items in the hard queue
l=0
for j in range(0,len(intervals)):
    for i in range(0,len(noise)):
        for k in range(0,num_graphs):
            if int(intervals[j]) <=4000:
                easy_work_queue.put({'datapt': l,'graph': graphs
[k],'noise': noise[i],'number_of_sets_of_data':
num_sets_of_data,'number_of_data_points':int(intervals[j])})
            else:
                hard_work_queue.put({'datapt': l,'graph': graphs
[k],'noise': noise[i],'number_of_sets_of_data':
num_sets_of_data,'number_of_data_points':int(intervals[j])})
            l+=1

#get number of cores and set the number on concurrent processes
num_hard_workers = 2
num_workers = multiprocessing.cpu_count()*1.5
easy_workers = []
hard_workers = []
#add poison pill for each worker and create the worker
for i in range(0,num_workers-num_hard_workers):
    easy_work_queue.put(None)
    easy_workers.append(multiprocessing.Process
(target=GP.RandomWalkGeneralizationErrorParallel,args=
(easy_work_queue,result_queue,)))
for i in range(0,num_hard_workers):
    hard_work_queue.put(None)
    hard_workers.append(multiprocessing.Process
(target=GP.RandomWalkGeneralizationErrorParallel,args=
(hard_work_queue,result_queue,)))

#run all workers
for worker in hard_workers:
    worker.start()
for worker in easy_workers:
    worker.start()
#wait for easy workers to finish
for worker in easy_workers:
    worker.join()
    print('worker joined')

#set off some of the easy workers on the hard work (maybe double
number of hard)
for i in range(0,num_hard_workers):
    hard_work_queue.put(None)
    hard_workers.append(multiprocessing.Process
(target=GP.RandomWalkGeneralizationErrorParallel,args=
(hard_work_queue,result_queue,)))
#wait for all hard workers to finish
for worker in hard_workers:
    worker.join()

#construct data from the mess in the result queue

tempdata = np.zeros(l)
while not result_queue.empty():
    data = result_queue.get()
    tempdata[data[0]] = data[1]

finaldata = tempdata.reshape((len(intervals),len(noise),num_graphs))

np.save(savefile,finaldata)

=======================================================
GaussianProcessRegression.py
=======================================================
import CovarianceFunction as CF
import networkx as nx
import numpy as np
import scipy.linalg as sp
#fortran code from lapack-blas (hopefully when scipy updated this wont
be needed)
import dtrsv
#to use more than one core
import multiprocessing

#Currently we assume Gaussian noise TODO change to general noise
#Assume 0 mean TODO change to general mean Gaussian Process
class GaussianProcessRegression:
    def __init__(self,covariance_function,sigma):
        #a covariance function object defined in CovarianceFunction
class
        #note this uses the parent class but any children can be used
        self.C = covariance_function
        #a list of pts that are known and their values
        self.pts = []
        self.vals = []
        #the inverse of K as defined in
        #@book{coolen05:theoryofneural,
	    #ISBN = {0-19-853024-2},
	    #publisher = {Oxford University Press, USA},
	    #author = {Coolen, A. C. C. and K{\"{u}}hn, R. and Sollich, P.},
	    #title = {Theory of neural information processing systems},
	    #year = {2005},
        #}
        self.K = np.array([])
        #gaussian noise variable
        self.sigma = float(sigma)
        self.cholL = np.array([])


    def add_data_points(self,points,vals):
       #add all points to list
       self.pts += points
       self.vals += vals
       arraysize = len(self.pts)
       #construct K
       K = np.zeros((arraysize,arraysize))
       #for speed
       pts = self.pts
       between_points = self.C.between_points
       if len(self.K):
            K[:-1,:-1] = self.K
       for i in xrange(0,arraysize):
           for j in xrange(arraysize-len(points),arraysize):
                 K[i,j] = between_points(pts[i],pts[j])
                 K[j,i] = K[i,j]
       K[arraysize-len(points):arraysize,arraysize-len
(points):arraysize] =  K[arraysize-len(points):arraysize,arraysize-len
(points):arraysize] + self.sigma**2 * np.eye(len(points))
       self.K = K

    #calculate the prediction of a point based on data previously
given
    def point_prediction(self,points):
        mean = []
        variance =[]
        arraysize = len(self.pts)
        #cholesky
        #if self.cholL.shape[0] < arraysize:
        L=np.linalg.cholesky(self.K)
        #    self.cholL = L
        #else:
        #    L = self.cholL

        alpha = sp.cho_solve((L,1),self.vals)
        #create L in banded form
        k=np.zeros((arraysize,len(points)))
 
##################################################################
        #for speed get ref to functions im going to use and save them
        between_points = self.C.between_points
        pts = self.pts
        dot = np.dot
 
##################################################################
        for j in xrange(0,len(points)):
            #create k
            for i in xrange(0,arraysize):
                k[i,j] = between_points(pts[i],points[j])

        #calculate mean and variance
        #call the command for forward substitution
        ###############fortran
call#######################################
        v = dtrsv.dtrsv('L','N',arraysize,L,k)
 
##################################################################

        #result
        mean=dot(alpha,k)
        for i in xrange(0,len(points)):
            variance.append(between_points(points[i],points[i]) - dot(v
[:,i],v[:,i]))
        #return it in dictionary form
        return {'mean':mean,'variance':variance}


    # calculate the error for data given, where function is a vector
    # of the function evaluated at a sufficiently large number of
points
    # that the GPregression has been trying to learn
    def error(self,function):
        total = 0
        #sum up variances
        result = self.point_prediction(function[::2])
        total = np.sum(result['variance'])
        total = (1/float(len(function)/2))*total
        return total

    #clear what has been learnt so far
    def clear(self):
        self.pts = []
        self.vals = []
        self.K = np.array([])

    #calculate the average error for a function defined in function
when give
    #number_of_examples examples
    def average_error_over_samples(self,function, sample_size,
number_of_examples):
        avg = 0
        numberofpoints = len(function)/2
        for i in range(0,sample_size):
            self.clear()
            #generate points of the function
            permpts = np.random.randint
(0,numberofpoints,number_of_examples)
            #create the vectors
            pts = []
            vals = []
            for j in range(0,number_of_examples):
                pts.append(function[permpts[j]*2])
                vals.append(function[permpts[j]*2+1])

            #learn these points
            self.add_data_points(pts,vals)
            #print("points added")
            avg = avg + self.error(function)
        avg = avg/sample_size
        return avg

    #calculate the average error over functions over data of size
number_of_data_points for MOST cases this is
    #also the generalization error a summary of which and
approximations to can be found in:
    #@inproceedings{Sollich99learningcurves,
	#booktitle = {Neural Computation},
	#author = {Sollich, P.},
	#title = {Learning curves for Gaussian process regression:
Approximations and bounds},
	#pages = {200-2},
	#year = {1999},
    #}

    def emprical_average_error_over_functions
(self,number_of_functions,number_of_sets_of_data,number_of_data_points,function_detail
=0,progress=0):
        avg = 0
        step = float(100)/number_of_functions
        for i in range(0,number_of_functions):
            if progress:
                print step*float(i),"%"
            if function_detail:
                fx = self.C.generate_function
(self.sigma,function_detail)
            else:
                fx = self.C.generate_function(self.sigma)
            avg = self.average_error_over_samples
(fx,number_of_sets_of_data,number_of_data_points)+avg
        avg = avg / number_of_functions
        return avg

    def average_error_over_functions
(self,number_of_sets_of_data,number_of_data_points,function_detail=0):
            if function_detail:
                fx = self.C.generate_function
(self.sigma,function_detail)
            else:
                fx = self.C.generate_function(self.sigma)
            avg = self.average_error_over_samples
(fx,number_of_sets_of_data,number_of_data_points)
            return(avg)



    def function_prediction(self,pts):
        temp = self.point_prediction(pts)
        return {'func':temp['mean'],'varpos':temp
['variance'],'varneg':-temp['variance']}


#########################################################################################################################################################
#Functions not contained in a class
#########################################################################################################################################################

#function to calculate the generalization error for a RandomWalk
kernel averaging over graphs graphs
def RandomWalkGeneralizationError
(noise,graphs,number_of_sets_of_data,number_of_data_points,a=2,p=10):
    graph_specific = np.zeros(len(graphs))
    avg = 0
    for i in range(0,len(graphs)):
        rw = CF.RandomWalk(a,p,graphs[i])
        GP = GaussianProcessRegression(rw,noise)
        graph_specific[i] = GP.average_error_over_functions
(number_of_sets_of_data,number_of_data_points)
    avg = np.sum(graph_specific)/len(graphs)
    return avg, graph_specific

#as above but using queues to create parallel architechture
def RandomWalkGeneralizationErrorParallel
(work_queue,result_queue,a=2,p=10):
    while True:
        input = work_queue.get()
        if input is None:
            print "poison"
            break
            print 'this should not appear'
        print input['datapt'], ' ', input['number_of_data_points']
        rw=CF.RandomWalk(a,p,input['graph'])
        GP = GaussianProcessRegression(rw,input['noise'])
        err = GP.average_error_over_functions(input
['number_of_sets_of_data'],input['number_of_data_points'])
        result_queue.put([input['datapt'],err])
    print 'here'
    return


From matt.urry at googlemail.com  Fri Jul 31 04:06:25 2009
From: matt.urry at googlemail.com (ma3mju)
Date: Fri, 31 Jul 2009 01:06:25 -0700 (PDT)
Subject: Processes not exiting
References: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
Message-ID: <28791ddd-5270-4a74-9c86-8fe719b34069@d4g2000yqa.googlegroups.com>

Sorry

###############fortran
call#######################################

 is meant to be

###############fortran call#######################################

Matt


From clp2 at rebertia.com  Fri Jul 31 04:07:41 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 01:07:41 -0700
Subject: problem on socket programming
In-Reply-To: <e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
Message-ID: <50697b2c0907310107v40f20d51ic5852303e545cd77@mail.gmail.com>

On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encrypt at gmail.com> wrote:
> now I've been encountered to some errors with this snippet :

And these errors are? Provide error messages and full tracebacks.

Cheers,
Chris
-- 
http://blog.rebertia.com


From masklinn at masklinn.net  Fri Jul 31 04:08:33 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 10:08:33 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <200907301757.48761.kyrie@uh.cu>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
Message-ID: <FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>

On 30 Jul 2009, at 23:57 , Luis Zarrabeitia wrote:
> I'd like to ask, what "container.each" is, exactly? It looks like a  
> function
> call (as I've learned a few posts ago), but, what are its arguments?  
> How the
> looping "works"? Does it receive a "code" object that it has to  
> execute?
> Is .each some kind of magic keyword? (This has little to do with  
> python or
> the current thread, so feel free to reply off-list if you want to...)

#each is simply a method that takes a function (called blocks in  
ruby). One could call it a higher-order method I guess.

It's an implementation of the concept of internal iteration: instead  
of collections yielding iterator objects, and programmers using those  
through specially-built iteration constructs (e.g. `for?in`),  
collections control iteration over themselves (the iteration is  
performed "inside" the collection, thus the "internal" part) and the  
programmer provides the operations to perform at each iterative step  
through (usually) a function.

In Python (assuming we had anonymous defs and an each method on  
lists), the following loop:

     for item in some_list:
         do_something(item)
         do_something_else(item)

     some_list.each((def (item):
         do_something(item)
         do_something_else(item)
     ))

There's absolutely nothing magic there, it's simply using anonymous  
functions and method calls (SmallTalk initiated this approach in the  
70s, and actually went much, much further than Ruby as it did away not  
only with `for?in` but also with `if?else` and `while` and a bunch of  
other stuff).

Now as IV pointed out, #each isn't the most interesting usage of  
blocks/anonymous functions (though I do like it, because it gets rid  
of no less than two keywords? even if Ruby reintroduced them as  
syntactic sugar), higher-order functions (functions which act on other  
functions) are (among other things) ways to create new control  
structures without having to extend the core language (so are lisp- 
style macros, by the way).

Of course Python does have higher-order functions (functions are first- 
class objects, so it's possible and frequent to have functions act on  
other functions), but since Python doesn't have anonymous functions  
that usage tends to be a bit too verbose beyond simple cases (also, of  
course, this kind of usages is neither in the "genes" nor in the  
stdlib).

In closing, IV has an example of how blocks make `with` unnecessary in  
Ruby (the functionality can be implemented at the library level rather  
than the language one). Generally, anonymous functions in OO languages  
are a way to inject behavior into third-party methods/objects. Kind-of  
a first-class Visitor support.

-m

PS: there's actually a bit of syntactic magic in Ruby's blocks, and  
it's one of the things I hate in the language, but it's not relevant  
to the role of blocks, and unnecessary to it: SmallTalk has no magical  
syntax).

From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 04:13:50 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 08:13:50 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
Message-ID: <008e82e8$0$9756$c3e8da3@news.astraweb.com>

On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:

> That and the fact that I couldn't stop laughing for long enough to learn
> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
> unlike less flexible languages, lets you alter the value of a constant."
> Yep, as they say "Bug" = "Undocumented feature"!

That's no different from Python's "constant by convention". We don't even 
get a compiler warning!

On the other hand, we don't have to prefix names with @ and @@, and we 
don't have the compiler trying to *guess* whether we're calling a 
function or referring to a variable.

Somebody who knows more Ruby than me should try writing the Zen of Ruby. 
Something like:

Line noise is beautiful.
Simplicity is for the simple.
Complicated just proves we're smart.
Readability only matters to the schmuck who has to maintain our code.
Special cases require breaking the rules.
In the face of ambiguity, try to guess. Go on, what could go wrong?
The more ways to do it, the better.

Although I'm sure Ruby has its good points. I'm not convinced anonymous 
code blocks are one of them though.


-- 
Steven


From hendrik at microcorp.co.za  Fri Jul 31 04:18:15 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 31 Jul 2009 10:18:15 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <7dca4iF2bgbn5U1@mid.individual.net>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3879.1248854780.8015.python-list@python.org>
	<7dca4iF2bgbn5U1@mid.individual.net>
Message-ID: <200907311018.15784.hendrik@microcorp.co.za>

On Thursday 30 July 2009 03:09:14 greg wrote:
> Hendrik van Rooyen wrote:
> > And if code is data, where is Pythons ALTER statement?
>
> class Duck:
>
>    def quack(self):
>      print "Quack!"
>
> def moo():
>    print "Moo!"
>
> def ALTER(obj, name, TO_PROCEED_TO):
>    setattr(obj, name, TO_PROCEED_TO)
>
> d = Duck()
> ALTER(d, 'quack', TO_PROCEED_TO = moo)
> d.quack()

Nice, and I really appreciate the Duck, 
but (there is always a but):

1) That is a function, not a statement.

2) The original changed a jump target address from
one address to another, and did not need the
heavy machinery of object oriented code.

So what you are doing is not quite the same.

It is actually not really needed in python, as
one can pass functions around, so that you can
call different things instead of jumping to them:

thing_to_call = moo
thing_to_call()

Does the equivalent without user level OO.

The original ALTER statement found use in building
fast state machines, where the next thing to do was
set up by the current state.  In python one simply returns
the next state.

The equivalent python code is easier to read as it is 
obvious what is happening - The COBOL source was
more obscure, as any jump could have been altered,
and you could not see that until you have read further
on in the program, where the ALTER statement was.

- Hendrik


From contact at xavierho.com  Fri Jul 31 04:21:45 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 18:21:45 +1000
Subject: Confessions of a Python fanboy
In-Reply-To: <FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
Message-ID: <2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <masklinn at masklinn.net> wrote:

> <snip>... but since Python doesn't have anonymous functions that usage
> tends to be a bit too verbose ... <snip>
>

Sorry to interrupt, but wouldn't lambda in Python be considered as
'anonymous functions'?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/f8e80b3e/attachment.html>

From clp2 at rebertia.com  Fri Jul 31 04:25:37 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 01:25:37 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
Message-ID: <50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>

On Fri, Jul 31, 2009 at 1:21 AM, Xavier Ho<contact at xavierho.com> wrote:
> On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <masklinn at masklinn.net> wrote:
>>
>> <snip>... but since Python doesn't have anonymous functions that usage
>> tends to be a bit too verbose ... <snip>
>
> Sorry to interrupt, but wouldn't lambda in Python be considered as
> 'anonymous functions'?

I believe "full" anonymous functions was intended by the author.
lambdas are limited to a single expression. "Full" anonymous functions
would be allowed to contain multiple statements.

Cheers,
Chris
-- 
http://blog.rebertia.com


From javier.collado at gmail.com  Fri Jul 31 04:27:01 2009
From: javier.collado at gmail.com (Javier Collado)
Date: Fri, 31 Jul 2009 10:27:01 +0200
Subject: Non-blocking read with popen subprocess
In-Reply-To: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
Message-ID: <c83cde5a0907310127x744e08e2rdefa402a1834c4a4@mail.gmail.com>

Hello,

According to my experience and from what I've read in other threads,
subprocess isn't easy to use for interactive tasks. I don't really
know, but maybe it wasn't even designed for that at all.

On the other hand, pexpect seems to work fine for interactive use and
even provides a method for nonblocking reads, so I think that you
should consider to take a look at it:
http://pexpect.sourceforge.net/pexpect.html#spawn-read_nonblocking

Best regards,
    Javier

2009/7/31 Dhanesh <dhaneshpai at gmail.com>:
> Hi ,
>
> I am trying to use subprocess popen on a windows command line
> executable with spits messages on STDOUT as well as STDIN. Code
> snippet is as below :-
> ##########################################################################
> sOut=""
> ? ?sErr=""
> ? ?javaLoaderPath = os.path.join("c:\\","Program Files","Research In
> Motion","BlackBerry JDE 4.7.0","bin","Javaloader.exe")
> ? ?cmd = [javaLoaderPath,'-u','load','helloworld.jad']
> ? ?popen = subprocess.Popen
> (cmd,bufsize=256,shell=False,stdout=subprocess.PIPE,
> stderr=subprocess.PIPE)
> ? ?while True:
> ? ? ? ?sErr = sErr + popen.stderr.read(64)
> ? ? ? ?sOut = sOut + popen.stdout.read(64)------------------> Blocks
> here
> ? ? ? ?if None != popen.poll():
> ? ? ? ? ? ?break;
> ##########################################################################
>
> I observed that python scripts blocks at stdout read on the other hand
> when I do not create a child stdout PIPE ?say ?" stdout=None" , things
> seems to be working fine.
>
> how can I we have a non blocking read ?
> And why does stdout block even where data is available to be read
> ( which seem to be apparent when stdout=None, and logs appear on
> parents STDOUT) ?
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From contact at xavierho.com  Fri Jul 31 04:31:43 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 18:31:43 +1000
Subject: Confessions of a Python fanboy
In-Reply-To: <50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
Message-ID: <2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:25 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> I believe "full" anonymous functions was intended by the author.
> lambdas are limited to a single expression. "Full" anonymous functions
> would be allowed to contain multiple statements.
>
> Cheers, but what about this:

 def goBig(x):
    while True:
        x = x ** 2
        yield x

for result in goBig(10):
    if result > 10 ** 100:
        break
    print result

It's a silly example, but wouldn't goBig(10) in this example be a "full
anonymous function"?

Just being curious.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/df0d8a3a/attachment.html>

From clp2 at rebertia.com  Fri Jul 31 04:38:16 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 01:38:16 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
	<2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>
Message-ID: <50697b2c0907310138u1ea485f9yf9bac0095e09927d@mail.gmail.com>

On Fri, Jul 31, 2009 at 1:31 AM, Xavier Ho<contact at xavierho.com> wrote:
> On Fri, Jul 31, 2009 at 6:25 PM, Chris Rebert <clp2 at rebertia.com> wrote:
>>
>> I believe "full" anonymous functions was intended by the author.
>> lambdas are limited to a single expression. "Full" anonymous functions
>> would be allowed to contain multiple statements.
>>
> Cheers, but what about this:
>
> ?def goBig(x):
> ??? while True:
> ??????? x = x ** 2
> ??????? yield x
>
> for result in goBig(10):
> ??? if result > 10 ** 100:
> ??????? break
> ??? print result
>
> It's a silly example, but wouldn't goBig(10) in this example be a "full
> anonymous function"?

No, because it has a name, namely "goBig"; this obviously prevents it
from being "anonymous".

For comparison, note how the function in the following example is
never given a name, and is thus anonymous:
>>> (lambda x: x+5)(6)
11

Cheers,
Chris
-- 
http://blog.rebertia.com


From malc0de.encrypt at gmail.com  Fri Jul 31 04:38:21 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 01:38:21 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
Message-ID: <67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>

On Jul 31, 12:07?pm, Chris Rebert <c... at rebertia.com> wrote:
> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
> > now I've been encountered to some errors with this snippet :
>
> And these errors are? Provide error messages and full tracebacks.
>
> Cheers,
> Chris
> --http://blog.rebertia.com

these are errors :

Traceback (most recent call last):
  File "echo-client.py", line 11, in <module
    sockobj.connect((serverHost,serverPort))
  File "<string>", line 1, in connect
socket.error: (10061, 'Connection refused')


From contact at xavierho.com  Fri Jul 31 04:41:17 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 18:41:17 +1000
Subject: Confessions of a Python fanboy
In-Reply-To: <50697b2c0907310138u1ea485f9yf9bac0095e09927d@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
	<2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>
	<50697b2c0907310138u1ea485f9yf9bac0095e09927d@mail.gmail.com>
Message-ID: <2d56febf0907310141m15bfc526i3c916f5a2b48f544@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:38 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> No, because it has a name, namely "goBig"; this obviously prevents it
> from being "anonymous".
>
> For comparison, note how the function in the following example is
> never given a name, and is thus anonymous:
> >>> (lambda x: x+5)(6)
> 11
>

Oh, I see. I was thinking in terms of using a variable to "give the function
a name". In that case, I understand. Thanks again for bearing me with my
random thoughts.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/9c3f4d35/attachment.html>

From hendrik at microcorp.co.za  Fri Jul 31 04:47:24 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 31 Jul 2009 10:47:24 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <4A719E2D.708@ieee.org>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com> <4A719E2D.708@ieee.org>
Message-ID: <200907311047.25029.hendrik@microcorp.co.za>

On Thursday 30 July 2009 15:20:45 Dave Angel wrote:

> As far as I know, nobody has yet built a microcode implementation of a
> Python VM (Virtual Machine).  Nor have I seen one for the Java VM.

Atmel has made an ARM that has support for Java Bytecode.

AT91SAM9X512 and friends (smaller versions)

- Hendrik


From greg at cosc.canterbury.ac.nz  Fri Jul 31 05:02:08 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Fri, 31 Jul 2009 21:02:08 +1200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <mailman.4022.1249028151.8015.python-list@python.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<mailman.3879.1248854780.8015.python-list@python.org>	<7dca4iF2bgbn5U1@mid.individual.net>
	<mailman.4022.1249028151.8015.python-list@python.org>
Message-ID: <7dfq78F2c8bolU1@mid.individual.net>

Hendrik van Rooyen wrote:
> The COBOL source was
> more obscure, as any jump could have been altered,
> and you could not see that until you have read further
> on in the program, where the ALTER statement was.

Well, in Python you can pretty much replace any
function with any other function, so you can
obfuscate things just as much if you really want!

-- 
Greg


From jeanmichel at sequans.com  Fri Jul 31 05:20:47 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 31 Jul 2009 11:20:47 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <80839e72-9df4-4590-b22d-4c5c829e37b6@h11g2000yqb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<mailman.4003.1248991082.8015.python-list@python.org>
	<80839e72-9df4-4590-b22d-4c5c829e37b6@h11g2000yqb.googlegroups.com>
Message-ID: <4A72B76F.4020805@sequans.com>

r wrote:
> The purpose of his thread was to get feedback on how Python
> and Ruby ideas could be cumulated into the best high level language.
> And being that i am the BDFL of the "Confessions of a Python Fanboy"
> thread, you have my personal permission to continue on with this
> subject matter...,
>
>   
Challenging even the most accepted mechanisms of a language is a proof 
of intelligence.

Descartes's doubt method :
"The basic strategy of /Descartes/ 
<http://www.philosophypages.com/ph/desc.htm>'s method of doubt 
<http://www.philosophypages.com/dy/d9.htm#doubt> is to defeat skepticism 
<http://www.philosophypages.com/dy/s5.htm#skep> on its own ground. Begin 
by doubting the truth of everything?not only the evidence 
<http://www.philosophypages.com/dy/e9.htm#evid> of the senses and the 
more extravagant cultural presuppositions, but even the fundamental 
process of reasoning itself. If any particular truth about the world can 
survive this extreme skeptical challenge, then it must be truly 
indubitable and therefore a perfectly certain foundation for knowledge"

So let's make the method call parenthesis a "truly indubitable and 
therefore a perfectly certain foundation".

Those who want to remove the parenthesis on python method calls raise 
the hand !

JM


From pyvault2.6 at gmail.com  Fri Jul 31 05:25:17 2009
From: pyvault2.6 at gmail.com (learner learner)
Date: Fri, 31 Jul 2009 14:55:17 +0530
Subject: file comparison
Message-ID: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>

Hi all,

I want to compare two text files line by line and eliminate the
matching/repeated line and store the unmatched/leftout lines into a third
file or overwrite into one of them.

regards
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/d9f3d5c1/attachment.html>

From lkrzysiak at gmail.com  Fri Jul 31 05:29:57 2009
From: lkrzysiak at gmail.com (=?UTF-8?Q?=C5=81ukasz?=)
Date: Fri, 31 Jul 2009 02:29:57 -0700 (PDT)
Subject: How to force SAX parser to ignore encoding problems
References: <89c214a4-e846-4101-b0b3-8078eec15114@w41g2000yqb.googlegroups.com>
Message-ID: <5587c712-1a15-4666-a5d9-5c99ace648f6@a13g2000yqc.googlegroups.com>

On 31 Lip, 09:28, ?ukasz <lkrzys... at gmail.com> wrote:
> Hi,
> I have a problem with my XML parser (created with libraries from
> xml.sax package). When parser finds a invalid character (in CDATA
> section) for example ,

After sending this message I noticed that example invalid characters
are not displaying on some platforms :)



From shearichard at gmail.com  Fri Jul 31 05:30:36 2009
From: shearichard at gmail.com (northof40)
Date: Fri, 31 Jul 2009 02:30:36 -0700 (PDT)
Subject: Python 2.6 in shared/VPS environment
References: <6babf860-0161-4c1a-82f8-69e03dc53da0@p36g2000prn.googlegroups.com>
Message-ID: <923e59f8-638c-4c2e-8b6a-b6e13d415424@j9g2000prh.googlegroups.com>

Ignore this question. Managed to get Amazon Web Services going and
have installed Python 2.6 on there. Thanks for your eyeballs time.

On Jul 31, 7:09?pm, northof40 <shearich... at gmail.com> wrote:
> Hi - I'd really like to have access to Python 2.6 to try something
> out. It needs to be on Linux/Unix machine. I don't mind paying but
> whichever way I turn I find Python 2.4 is the standard installation.
>
> Anyone know of anyone who offers this out of the box ? Or got any
> smart way of achieving it ?
>
> thanks
>
> R.



From contact at xavierho.com  Fri Jul 31 05:34:58 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 19:34:58 +1000
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <2d56febf0907310234h5bda3a66m66f71201efb92fe8@mail.gmail.com>

On Fri, Jul 31, 2009 at 7:25 PM, learner learner <pyvault2.6 at gmail.com>wrote:

> Hi all,
>
> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a third
> file or overwrite into one of them.
>

Sounds like homework to me. Why not look into:

- the file() function and its methods.

It's in the documentation.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/ab6e2777/attachment.html>

From gh at ghaering.de  Fri Jul 31 05:35:03 2009
From: gh at ghaering.de (=?ISO-8859-1?Q?Gerhard_H=E4ring?=)
Date: Fri, 31 Jul 2009 11:35:03 +0200
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <h4uds7$8p2$1@ger.gmane.org>

learner learner wrote:
> Hi all,
>  
> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a
> third file or overwrite into one of them.

gl & hf!



From clp2 at rebertia.com  Fri Jul 31 05:37:25 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 02:37:25 -0700
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <50697b2c0907310237y2c79e938g70952e966b74ce87@mail.gmail.com>

On Fri, Jul 31, 2009 at 2:25 AM, learner learner<pyvault2.6 at gmail.com> wrote:
> Hi all,
>
> I?want to compare two text files line by line and eliminate the
> matching/repeated?line and store the unmatched/leftout lines into?a third
> file or overwrite into one of them.

See the `difflib` module:
http://docs.python.org/library/difflib.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From duncan.booth at invalid.invalid  Fri Jul 31 05:41:34 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 31 Jul 2009 09:41:34 GMT
Subject: Generators through the C API
References: <mailman.4015.1249008960.8015.python-list@python.org>
Message-ID: <Xns9C596B31CD31Bduncanbooth@127.0.0.1>

Lucas P Melo <lukepadawan at gmail.com> wrote:

> Hello, I'm a total noob about the C API. Is there any way to create a 
> generator function using the C API? I couldn't find anything like the 
> 'yield' keyword in it.
> 
> Thanks in advance.

You define a new type with tp_flags including Py_TPFLAGS_HAVE_ITER. 
Anything that would be a local variable in your generator needs to become 
an attribute in the type.

The tp_init initialization function should contain all the code up to the 
first yield, tp_iter should return self and tp_iternext should execute code 
up to the next yield.

-- 
Duncan Booth http://kupuguy.blogspot.com


From masklinn at masklinn.net  Fri Jul 31 05:49:31 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 11:49:31 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
Message-ID: <C497400A-9853-4344-91D4-0A82ABF717DF@masklinn.net>

On 31 Jul 2009, at 10:25 , Chris Rebert wrote:
> On Fri, Jul 31, 2009 at 1:21 AM, Xavier Ho<contact at xavierho.com>  
> wrote:
>> On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <masklinn at masklinn.net>  
>> wrote:
>>>
>>> <snip>... but since Python doesn't have anonymous functions that  
>>> usage
>>> tends to be a bit too verbose ... <snip>
>>
>> Sorry to interrupt, but wouldn't lambda in Python be considered as
>> 'anonymous functions'?
>
> I believe "full" anonymous functions was intended by the author.
> lambdas are limited to a single expression.
Yes, and they're limited to a single *expression*, so before Python 3,  
lambda: print "foo" is out. Likewise, it isn't possible to have an if/ 
else statement within a lambda (though a ternary is ok), or a with, ?  
since Python statements aren't expressions.

From iainking at gmail.com  Fri Jul 31 05:54:50 2009
From: iainking at gmail.com (Iain King)
Date: Fri, 31 Jul 2009 02:54:50 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<mailman.4006.1248995212.8015.python-list@python.org>
	<008e7846$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <a46c8c91-a45d-43fe-aa16-f6e4df2201bb@d4g2000yqa.googlegroups.com>

On Jul 31, 8:28?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Thu, 30 Jul 2009 18:06:31 -0500, Robert Kern wrote:
> > On 2009-07-30 16:44, r wrote:
> >> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com> wrote:
> >>>> 1.) No need to use "()" to call a function with no arguments. Python
> >>>> --> ?"obj.m2().m3()" --ugly
> >>>> ? ?Ruby --> ?"obj.m1.m2.m3" ?-- sweeet!
> >>>> Man, i must admit i really like this, and your code will look so much
> >>>> cleaner.
> >>> It has benefits - code does look better. It has also significant cons
> >>> - it is ambiguous.
> >>> For instance:
>
> >>> a = b
>
> >>> Is b a variable or a method called without parameter?
>
> >> Hello Emanuel,
> >> Again, who so ever names a method with such a non-descriptive name will
> >> get whats coming to him. And if you did for some reason use such a
> >> cryptic name as "b", do yourself (and everyone else) a favor and follow
> >> it with "()" to denote the method call. Remember when something is
> >> optional that means you have an option to use it OR not use it.
>
> > I believe his point is that it is ambiguous to the compiler, not humans
> > reading the code. Python functions and methods are first class objects.
> > They can be passed around. If they were auto-called, then you could not
> > do this.
>
> Oh my, "r" is still around is he??? And now he's singing the praises of
> Ruby, the language which he treated as the Devil's Spawn when he first
> arrived. That's hilarious.
>
> But back on topic... "r" has missed the point. It's not that a=b is hard
> to understand because b is a poor name. The example could have been:
>
> def factory_function():
> ? ? magic = time.time() ?# or whatever
> ? ? def inner():
> ? ? ? ? return magic
> ? ? return inner
>
> my_function = factory_function
>
> It's still ambiguous. Does the programmer intend my_function to become
> factory_function itself, or the output of factory_function?

Not only that - does 'return inner' return the function inner or the
result of function inner?

How does ruby pass a function as an object?

Iain


From piet at cs.uu.nl  Fri Jul 31 06:01:09 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 31 Jul 2009 12:01:09 +0200
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
Message-ID: <m2r5vxuq6y.fsf@cs.uu.nl>

>>>>> MalC0de <malc0de.encrypt at gmail.com> (M) wrote:

>M> On Jul 31, 12:07?pm, Chris Rebert <c... at rebertia.com> wrote:
>>> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
>>> > now I've been encountered to some errors with this snippet :
>>> 
>>> And these errors are? Provide error messages and full tracebacks.
>>> 
>>> Cheers,
>>> Chris
>>> --http://blog.rebertia.com

>M> these are errors :

>M> Traceback (most recent call last):
>M>   File "echo-client.py", line 11, in <module
>M>     sockobj.connect((serverHost,serverPort))
>M>   File "<string>", line 1, in connect
>M> socket.error: (10061, 'Connection refused')

Is your server running?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Fri Jul 31 06:27:31 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 31 Jul 2009 12:27:31 +0200
Subject: Processes not exiting
References: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
Message-ID: <m2my6luoz0.fsf@cs.uu.nl>

>>>>> ma3mju <matt.urry at googlemail.com> (m) wrote:

>m> Hi all,
>m> I'm having trouble with multiprocessing I'm using it to speed up some
>m> simulations, I find for large queues when the process reaches the
>m> poison pill it does not exit whereas for smaller queues it works
>m> without any problems. Has anyone else had this trouble? Can anyone
>m> tell me a way around it? The code is in two files below.

How do you know it doesn't exit. You haven't shown any of your output.

I did discover a problem in your code, but it should cause an exception:

>m> #set off some of the easy workers on the hard work (maybe double
>m> number of hard)
>m> for i in range(0,num_hard_workers):
>m>     hard_work_queue.put(None)
>m>     hard_workers.append(multiprocessing.Process
>m> (target=GP.RandomWalkGeneralizationErrorParallel,args=
>m> (hard_work_queue,result_queue,)))
>m> #wait for all hard workers to finish
>m> for worker in hard_workers:
>m>     worker.join()

Here you create new hard workers, but you never start them. The join
should then give an exception when it reaches these.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From masklinn at masklinn.net  Fri Jul 31 06:32:56 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 12:32:56 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <a46c8c91-a45d-43fe-aa16-f6e4df2201bb@d4g2000yqa.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<mailman.4006.1248995212.8015.python-list@python.org>
	<008e7846$0$9756$c3e8da3@news.astraweb.com>
	<a46c8c91-a45d-43fe-aa16-f6e4df2201bb@d4g2000yqa.googlegroups.com>
Message-ID: <1AD26B34-17FA-4315-8A4F-B3F3D09F7D29@masklinn.net>

On 31 Jul 2009, at 11:54 , Iain King wrote:
> On Jul 31, 8:28 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>> On Thu, 30 Jul 2009 18:06:31 -0500, Robert Kern wrote:
>>> On 2009-07-30 16:44, r wrote:
>>>> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com>  
>>>> wrote:
>>>>>> 1.) No need to use "()" to call a function with no arguments.  
>>>>>> Python
>>>>>> -->  "obj.m2().m3()" --ugly
>>>>>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
>>>>>> Man, i must admit i really like this, and your code will look  
>>>>>> so much
>>>>>> cleaner.
>>>>> It has benefits - code does look better. It has also significant  
>>>>> cons
>>>>> - it is ambiguous.
>>>>> For instance:
>>
>>>>> a = b
>>
>>>>> Is b a variable or a method called without parameter?
>>
>>>> Hello Emanuel,
>>>> Again, who so ever names a method with such a non-descriptive  
>>>> name will
>>>> get whats coming to him. And if you did for some reason use such a
>>>> cryptic name as "b", do yourself (and everyone else) a favor and  
>>>> follow
>>>> it with "()" to denote the method call. Remember when something is
>>>> optional that means you have an option to use it OR not use it.
>>
>>> I believe his point is that it is ambiguous to the compiler, not  
>>> humans
>>> reading the code. Python functions and methods are first class  
>>> objects.
>>> They can be passed around. If they were auto-called, then you  
>>> could not
>>> do this.
>>
>> Oh my, "r" is still around is he??? And now he's singing the  
>> praises of
>> Ruby, the language which he treated as the Devil's Spawn when he  
>> first
>> arrived. That's hilarious.
>>
>> But back on topic... "r" has missed the point. It's not that a=b is  
>> hard
>> to understand because b is a poor name. The example could have been:
>>
>> def factory_function():
>>     magic = time.time()  # or whatever
>>     def inner():
>>         return magic
>>     return inner
>>
>> my_function = factory_function
>>
>> It's still ambiguous. Does the programmer intend my_function to  
>> become
>> factory_function itself, or the output of factory_function?
>
> Not only that - does 'return inner' return the function inner or the
> result of function inner?
>
> How does ruby pass a function as an object?
Ruby doesn't have functions as such. It has methods and blocks (which  
would be anonymous functions). `def` always creates methods.

To get a (bound) method object, you simply call `method` on an  
instance e.g. `foo.method(:bar)` is equivalent to `foo.bar` in Python  
(it returns a bound method object without calling it).

Blocks are usually created as part of the calls: `foo.bar  
{do_something}` the part between braces (braces included) is a block,  
which will be passed to the method `bar`. Sadly, Ruby's blocks are  
magical syntax (doesn't mean they have to be, in Smalltalk there's  
nothing magical about blocks for instance) so you can't just do `foo =  
{do_something}`, you have to turn them into `Proc` objects with the  
`proc` constructor (or `lambda`, it's equivalent and looks better so  
I'll use that): `foo = lambda {do_something}`. If you use the magical  
syntax previously shown, Ruby handles the turning of a block into an  
actual `Proc` instance.

And since Ruby doesn't have a `()` operator, it uses a method instead  
(`#call`), so you simply do `foo.call` to execute the proc and get its  
value.

All in all, much like Smalltalk, Ruby tends not to favor raw functions  
the way Python does, so a direct translation of the Python code  
doesn't make much sense.


From python at mrabarnett.plus.com  Fri Jul 31 06:34:29 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 11:34:29 +0100
Subject: Processes not exiting
In-Reply-To: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
References: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
Message-ID: <4A72C8B5.1030309@mrabarnett.plus.com>

ma3mju wrote:
> Hi all,
> 
> I'm having trouble with multiprocessing I'm using it to speed up some
> simulations, I find for large queues when the process reaches the
> poison pill it does not exit whereas for smaller queues it works
> without any problems. Has anyone else had this trouble? Can anyone
> tell me a way around it? The code is in two files below.
> 
[snip]
> 
> #get number of cores and set the number on concurrent processes
> num_hard_workers = 2
> num_workers = multiprocessing.cpu_count()*1.5
> easy_workers = []
> hard_workers = []
> #add poison pill for each worker and create the worker
> for i in range(0,num_workers-num_hard_workers):
>     easy_work_queue.put(None)
>     easy_workers.append(multiprocessing.Process
> (target=GP.RandomWalkGeneralizationErrorParallel,args=
> (easy_work_queue,result_queue,)))
> for i in range(0,num_hard_workers):
>     hard_work_queue.put(None)
>     hard_workers.append(multiprocessing.Process
> (target=GP.RandomWalkGeneralizationErrorParallel,args=
> (hard_work_queue,result_queue,)))
> 
You have 2 hard workers and ceil(CPU_count * 1.5) - 2 easy workers.
What if the number of CPUs was 1? That would give 2 hard and 0 easy!

Also, I recommend that you put only 1 'poison pill' in each queue and
have the workers put it back when they see it.



From hendrik at microcorp.co.za  Fri Jul 31 06:47:30 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 31 Jul 2009 12:47:30 +0200
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <200907311247.30793.hendrik@microcorp.co.za>

On Friday 31 July 2009 11:25:17 learner learner wrote:
> Hi all,
>
> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a third
> file or overwrite into one of them.

This is not as simple as it seems.

You will probably be better off using diff, or,
if it is a learning exercise, studying its source.

- Hendrik



From deets at nospam.web.de  Fri Jul 31 07:26:06 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 31 Jul 2009 13:26:06 +0200
Subject: problem on socket programming
In-Reply-To: <67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
Message-ID: <4A72D4CE.6030501@nospam.web.de>

MalC0de schrieb:
> On Jul 31, 12:07 pm, Chris Rebert <c... at rebertia.com> wrote:
>> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
>>> now I've been encountered to some errors with this snippet :
>> And these errors are? Provide error messages and full tracebacks.
>>
>> Cheers,
>> Chris
>> --http://blog.rebertia.com
> 
> these are errors :
> 
> Traceback (most recent call last):
>   File "echo-client.py", line 11, in <module
>     sockobj.connect((serverHost,serverPort))
>   File "<string>", line 1, in connect
> socket.error: (10061, 'Connection refused')

Can you ping and telnet to the port on the desired server? Firewalls can 
be an issue here.

Diez


From deets at nospam.web.de  Fri Jul 31 07:26:41 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 31 Jul 2009 13:26:41 +0200
Subject: problem on socket programming
In-Reply-To: <67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
Message-ID: <7dg2niF2bue0tU2@mid.uni-berlin.de>

MalC0de schrieb:
> On Jul 31, 12:07 pm, Chris Rebert <c... at rebertia.com> wrote:
>> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
>>> now I've been encountered to some errors with this snippet :
>> And these errors are? Provide error messages and full tracebacks.
>>
>> Cheers,
>> Chris
>> --http://blog.rebertia.com
> 
> these are errors :
> 
> Traceback (most recent call last):
>   File "echo-client.py", line 11, in <module
>     sockobj.connect((serverHost,serverPort))
>   File "<string>", line 1, in connect
> socket.error: (10061, 'Connection refused')

Can you ping and telnet to the port on the desired server? Firewalls can 
be an issue here.

Diez


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 31 07:38:56 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 31 Jul 2009 13:38:56 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <008e82e8$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <4a72d7cf$0$25239$426a34cc@news.free.fr>

Steven D'Aprano a ?crit :
> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
> 
>> That and the fact that I couldn't stop laughing for long enough to learn
>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>> unlike less flexible languages, lets you alter the value of a constant."
>> Yep, as they say "Bug" = "Undocumented feature"!
> 
> That's no different from Python's "constant by convention".

Well, at least Python doesn't pretend to have real symbolic constants - 
we all know it's only a convention !-)

> We don't even 
> get a compiler warning!

Of course - from the compiler's POV, it's only usual rebinding.

> On the other hand, we don't have to prefix names with @ and @@,

Nope, we have to prefix them with 'self' or 'cls' (or even 
'self.__class__').

> and we 
> don't have the compiler trying to *guess* whether we're calling a 
> function or referring to a variable.

Please re-read a bit more carefully - it's *all* method call. Python is 
'uniform' in obj.name is always an attribute lookup (methods being 
attributes), Ruby is uniform in that 'obj.name' is always a method call.

> Somebody who knows more Ruby than me should try writing the Zen of Ruby. 
> Something like:

(snip childish parody of Python Zen)

Steven, is that any useful ?

> 
> Although I'm sure Ruby has its good points. I'm not convinced anonymous 
> code blocks are one of them though.

Ruby's code blocks come from Smalltalk, where they are an absolute 
necessity since message passing (which code blocks are part of) is the 
*only* builtin control flow in Smalltalk - so you just *need* this 
construction to provide branching and iterations.

Wether it makes sense to have code blocks in Ruby is another question 
since Ruby does provide traditional control flow features, but then one 
could question Python's "lambda" (hem...) too.


From j.sundo at cs.ucl.ac.uk  Fri Jul 31 07:41:49 2009
From: j.sundo at cs.ucl.ac.uk (=?ISO-8859-1?Q?Jannik_Sund=F8?=)
Date: Fri, 31 Jul 2009 12:41:49 +0100
Subject: Confused About Python Loggin
In-Reply-To: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>
References: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>
Message-ID: <14CCA71D-F575-4B8A-8C99-67BDAAC2C6E0@cs.ucl.ac.uk>

Hi all. I think I fixed this problem by setting fileLogger.propagate =  
0. Otherwise it will propagate up to the root logger, which outputs to  
stdout, as far as I can understand.


On 31 Jul 2009, at 01:17, Jannik Sund? wrote:

> Dear all, I am quite confused about the Python logging. I have read  
> and re-read the Python documentation for the Python logging module  
> and googled, but to no avail. I simply want one logger to log to a  
> file and another logger to log to the console. Neither should log  
> the other's messages. The code below causes fileLogger to log to  
> BOTH a file and the console, how come? It seems to me that a call  
> such as "consoleHandler = logging.StreamHandler()" affects other  
> loggers, which I do not want. Also, if I do not do  
> logging.basicConfig(level=logging.INFO) in one of the classes of my  
> application, the logging does not work. Any ideas how come?
>
> Thanks a lot for any help! :)
>
> fileHandler = logging.FileHandler('../../logs/log.txt')
> fileLogger = logging.getLogger('TESTHARNESSFILE')
> fileLogger.addHandler(fileHandler)
> fileLogger.setLevel(logging.INFO)
> consoleHandler = logging.StreamHandler()
> logger = logging.getLogger('TESTHARNESS')
> logger.addHandler(consoleHandler)
> logger.setLevel(logging.INFO)



From malc0de.encrypt at gmail.com  Fri Jul 31 07:49:09 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 04:49:09 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
Message-ID: <5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>


you want to say shall i  disable the firewall, there's no specific
firewall or IPS/IDS system out there, this is just windows xp firewall


From deets at nospam.web.de  Fri Jul 31 08:08:25 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 31 Jul 2009 14:08:25 +0200
Subject: problem on socket programming
In-Reply-To: <5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
Message-ID: <7dg55pF2bfubpU1@mid.uni-berlin.de>

MalC0de schrieb:
> you want to say shall i  disable the firewall, there's no specific
> firewall or IPS/IDS system out there, this is just windows xp firewall

Which is a firewall, don't you agree? So it could well be the reason for 
the problems you see.

Diez


From masklinn at masklinn.net  Fri Jul 31 08:18:56 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 14:18:56 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a72d7cf$0$25239$426a34cc@news.free.fr>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
Message-ID: <23AB2CC9-71D1-4498-8D23-D3648C00DD4C@masklinn.net>

On 31 Jul 2009, at 13:38 , Bruno Desthuilliers wrote:
> Steven D'Aprano a ?crit :
>> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>> That and the fact that I couldn't stop laughing for long enough to  
>>> learn
>>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>>> unlike less flexible languages, lets you alter the value of a  
>>> constant."
>>> Yep, as they say "Bug" = "Undocumented feature"!
>> That's no different from Python's "constant by convention".
> Ruby's code blocks come from Smalltalk, where they are an absolute  
> necessity since message passing (which code blocks are part of) is  
> the *only* builtin control flow in Smalltalk - so you just *need*  
> this construction to provide branching and iterations.
>
I'm not so sure about the way you say it. I'm pretty sure  
"traditional" flow control structures preceded Smalltalk by a pair of  
decades so it's not that Smalltalk's designers found it necessary to  
use blocks & messages, but that they understood blocks & messages  
could trivially replace most control structures (making *those*  
unnecessary), making the core language simpler and more flexible.

In other words, I see it the other way around.

> Wether it makes sense to have code blocks in Ruby is another  
> question since Ruby does provide traditional control flow features
Well it does at least allow for the creation of new flow control  
structures in library land when the existing ones aren't enough (e.g.  
allows Ruby not to require the introduction of a `with` statement).  
Though Ruby's blocks are nowhere near as flexible as Smalltalk's.

From vinay_sajip at yahoo.co.uk  Fri Jul 31 08:24:58 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Fri, 31 Jul 2009 05:24:58 -0700 (PDT)
Subject: Confused About Python Loggin
References: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk> 
	<mailman.4040.1249040521.8015.python-list@python.org>
Message-ID: <21effe68-2202-4f58-a2d9-f1ea3968149a@d32g2000yqh.googlegroups.com>

On Jul 31, 12:41?pm, Jannik Sund? <j.su... at cs.ucl.ac.uk> wrote:
> Hi all. I think I fixed this problem by setting fileLogger.propagate = ?
> 0. Otherwise it will propagate up to the root logger, which outputs to ?
> stdout, as far as I can understand.
>

Only if you specifically configure it to do so - for example, calling
basicConfig() configures the root logger (if it has no handlers) by
adding a StreamHandler which outputs to sys.stderr.

You shouldn't need to set propagate - the script in Peter's reply
appears to do what you need.

Regards,

Vinay Sajip


From malc0de.encrypt at gmail.com  Fri Jul 31 08:37:21 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 05:37:21 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
	<7dg55pF2bfubpU1@mid.uni-berlin.de>
Message-ID: <f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>

no, I disabled my firewall, no problem with even enabled firewall ...
no one can help !?


From davea at ieee.org  Fri Jul 31 08:55:27 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 31 Jul 2009 08:55:27 -0400
Subject: file comparison
In-Reply-To: <200907311247.30793.hendrik@microcorp.co.za>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
	<200907311247.30793.hendrik@microcorp.co.za>
Message-ID: <4A72E9BF.3080808@ieee.org>

Hendrik van Rooyen wrote:
> On Friday 31 July 2009 11:25:17 learner learner wrote:
>   
>> Hi all,
>>
>> I want to compare two text files line by line and eliminate the
>> matching/repeated line and store the unmatched/leftout lines into a third
>> file or overwrite into one of them.
>>     
>
> This is not as simple as it seems.
>
> You will probably be better off using diff, or,
> if it is a learning exercise, studying its source.
>
> - Hendrik
>
>
>   

It is not only "not simple," it's totally underspecified.


Learner:

If this is a homework assignment, you should read the whole assignment, 
and see what it says.  Without knowing something about the text files, I 
couldn't even guess what the real goal is.

For example, if the text files are really text (e.g. a letter to 
grandma), then we want a context-sensitive comparison, the kind that 
Windiff, RCSDiff, DiffMerge, and others can do.

If the text files are each a list of items, with order and duplication 
irrelevant, then your best bet is probably to build a set from each, and 
difference the sets.

DaveA


From jeanmichel at sequans.com  Fri Jul 31 09:04:59 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 31 Jul 2009 15:04:59 +0200
Subject: Confused About Python Loggin
In-Reply-To: <14CCA71D-F575-4B8A-8C99-67BDAAC2C6E0@cs.ucl.ac.uk>
References: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>
	<14CCA71D-F575-4B8A-8C99-67BDAAC2C6E0@cs.ucl.ac.uk>
Message-ID: <4A72EBFB.4080306@sequans.com>

Jannik Sund? wrote:
> Hi all. I think I fixed this problem by setting fileLogger.propagate = 
> 0. Otherwise it will propagate up to the root logger, which outputs to 
> stdout, as far as I can understand.
>
>
> On 31 Jul 2009, at 01:17, Jannik Sund? wrote:
>
>> Dear all, I am quite confused about the Python logging. I have read 
>> and re-read the Python documentation for the Python logging module 
>> and googled, but to no avail. I simply want one logger to log to a 
>> file and another logger to log to the console. Neither should log the 
>> other's messages. The code below causes fileLogger to log to BOTH a 
>> file and the console, how come? It seems to me that a call such as 
>> "consoleHandler = logging.StreamHandler()" affects other loggers, 
>> which I do not want. Also, if I do not do 
>> logging.basicConfig(level=logging.INFO) in one of the classes of my 
>> application, the logging does not work. Any ideas how come?
>>
>> Thanks a lot for any help! :)
>>
>> fileHandler = logging.FileHandler('../../logs/log.txt')
>> fileLogger = logging.getLogger('TESTHARNESSFILE')
>> fileLogger.addHandler(fileHandler)
>> fileLogger.setLevel(logging.INFO)
>> consoleHandler = logging.StreamHandler()
>> logger = logging.getLogger('TESTHARNESS')
>> logger.addHandler(consoleHandler)
>> logger.setLevel(logging.INFO)
>
> --http://mail.python.org/mailman/listinfo/python-list
>
Please do not top post :o)

Are sure you have used the code provided above ?
Loggers only propagate events to its parent.

fileLogger = logging.getLogger('TESTHARNESSFILE"
logger = logging.getLogger('TESTHARNESS')
Those one have no parent relationship.

However these one have parent relationship:
fileLogger = logging.getLogger('TESTHARNESS.FILE") # note the dotted name
logger = logging.getLogger('TESTHARNESS')


Or maybe you have added a handler to the root logger...

Using the propagate attribute is correct only between 2 loggers that are 
meant to be parents.

JM


From python at mrabarnett.plus.com  Fri Jul 31 09:05:35 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 14:05:35 +0100
Subject: problem on socket programming
In-Reply-To: <f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>	<7dg2niF2bue0tU2@mid.uni-berlin.de>	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>	<7dg55pF2bfubpU1@mid.uni-berlin.de>
	<f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
Message-ID: <4A72EC1F.7040709@mrabarnett.plus.com>

MalC0de wrote:
> no, I disabled my firewall, no problem with even enabled firewall ...
> no one can help !?

I hope you disconnected your computer from the internet before disabling
the firewall...



From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 31 09:12:42 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 31 Jul 2009 15:12:42 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.4041.1249042752.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>	<008e82e8$0$9756$c3e8da3@news.astraweb.com>	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<mailman.4041.1249042752.8015.python-list@python.org>
Message-ID: <4a72edca$0$32755$426a74cc@news.free.fr>

Masklinn a ?crit :
> On 31 Jul 2009, at 13:38 , Bruno Desthuilliers wrote:
>> Steven D'Aprano a ?crit :
>>> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>>> That and the fact that I couldn't stop laughing for long enough to 
>>>> learn
>>>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>>>> unlike less flexible languages, lets you alter the value of a 
>>>> constant."
>>>> Yep, as they say "Bug" = "Undocumented feature"!
>>> That's no different from Python's "constant by convention".
>> Ruby's code blocks come from Smalltalk, where they are an absolute 
>> necessity since message passing (which code blocks are part of) is the 
>> *only* builtin control flow in Smalltalk - so you just *need* this 
>> construction to provide branching and iterations.
>>
> I'm not so sure about the way you say it.

I'm not sure about the way you understand it !-)

> I'm pretty sure "traditional" 
> flow control structures preceded Smalltalk by a pair of decades

Yes, of course - and that's not the point. What's important is that:


> so it's 
> not that Smalltalk's designers found it necessary to use blocks & 
> messages, but that they understood blocks & messages could trivially 
> replace most control structures (making *those* unnecessary), making the 
> core language simpler and more flexible.

Exactly.

> In other words, I see it the other way around.

My wording may have been a bit confusing, indeed. It was implied (but 
perhaps a bit unclear) that restricting control structures to messages 
and blocks was a design choice.

>> Wether it makes sense to have code blocks in Ruby is another question 
>> since Ruby does provide traditional control flow features
 >
> Well it does at least allow for the creation of new flow control 
> structures in library land when the existing ones aren't enough (e.g. 
> allows Ruby not to require the introduction of a `with` statement). 

Yeps. But then other "traditionnal" control flow features become redundant.

> Though Ruby's blocks are nowhere near as flexible as Smalltalk's.


From processor.dev1l at gmail.com  Fri Jul 31 09:15:00 2009
From: processor.dev1l at gmail.com (Processor-Dev1l)
Date: Fri, 31 Jul 2009 06:15:00 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
	<7dg55pF2bfubpU1@mid.uni-berlin.de>
	<f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
Message-ID: <72f851f9-a2d4-4448-900d-3fe20e4ebeb0@w41g2000yqb.googlegroups.com>

On Jul 31, 2:37?pm, MalC0de <malc0de.encr... at gmail.com> wrote:
> no, I disabled my firewall, no problem with even enabled firewall ...
> no one can help !?

Connection refused... connection was refused by the listening socket,
it could also be due to the settings of your service, if it accepts
only from localhost to localhost (127.0.0.1 to 127.0.0.1) then other
connections will not be granted. Try to find some socket samples on
python.org (there are plenty of tip and tricks for using sockets)


From processor.dev1l at gmail.com  Fri Jul 31 09:21:14 2009
From: processor.dev1l at gmail.com (Processor-Dev1l)
Date: Fri, 31 Jul 2009 06:21:14 -0700 (PDT)
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org> 
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com> 
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com> 
	<4A7199FF.8010202@dejaviewphoto.com>
	<mailman.4030.1249031631.8015.python-list@python.org>
Message-ID: <52bdb49f-935f-459c-bc64-76e5ccb16f36@k6g2000yqn.googlegroups.com>

On Jul 30, 4:47?pm, "Barak, Ron" <Ron.Ba... at lsi.com> wrote:
> > -----Original Message-----
> > From: Dave Angel [mailto:da... at dejaviewphoto.com]
> > Sent: Thursday, July 30, 2009 16:03
> > To: Barak, Ron
> > Cc: 'Dave Angel'; 'python-l... at python.org'
> > Subject: RE: Run pyc file without specifying python path ?
>
> > Barak, Ron wrote:
> > >> -----Original Message-----
> > >> From: Dave Angel [mailto:da... at ieee.org]
> > >> Sent: Wednesday, July 29, 2009 21:05
> > >> To: Barak, Ron
> > >> Cc: 'python-l... at python.org'
> > >> Subject: Re: Run pyc file without specifying python path ?
>
> > >> Barak, Ron wrote:
>
> > >>> Hi,
>
> > >>> I wanted to make a python byte-code file executable,
>
> > >> expecting to be able to run it without specifying "python" on the
> > >> (Linux bash) command line.
>
> > >>> So, I wrote the following:
>
> > >>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
>
> > >>> print "hello"
> > >>> [root at VMLinux1 python]#
>
> > >>> and made its pyc file executable:
>
> > >>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> > >>> 4 -rwxr-xr-x ?1 root root 106 Jul 29 14:22 test_pyc.pyc
> > >>> [root at VMLinux1 python]#
>
> > >>> So, I see:
>
> > >>> [root at VMLinux1 python]# file test_pyc.py*
> > >>> test_pyc.py: ?a python script text executable
> > >>> test_pyc.pyc: python 2.3 byte-compiled
> > >>> [root at VMLinux1 python]#
>
> > >>> If I try to do the following, no problem:
>
> > >>> [root at VMLinux1 python]# python test_pyc.pyc hello
> > >>> [root at VMLinux1 python]#
>
> > >>> However, the following fails:
>
> > >>> [root at VMLinux1 python]# ./test_pyc.pyc
> > >>> -bash: ./test_pyc.pyc: cannot execute binary file
> > >>> [root at VMLinux1 python]#
>
> > >>> Is there a way to run a pyc file without specifying the
>
> > >> python path ?
>
> > >>> Bye,
> > >>> Ron.
>
> > >> I don't currently run Unix, but I think I know the problem.
>
> > >> In a text file, the shell examines the first line, and if
> > it begins
> > >> #!
> > >> it's assumed to point to the executable of an interpreter for that
> > >> text file. ?Presumably the same trick doesn't work for a .pyc file.
>
> > >> Why not write a trivial wrapper.py file, don't compile it, and let
> > >> that invoke the main code in the .pyc file?
>
> > >> Then make wrapper.py executable, and you're ready to go.
>
> > >> DaveA
>
> > > Hi Dave,
> > > Your solution sort of defeats my intended purpose (sorry
> > for not divulging my 'hidden agenda').
> > > I wanted my application to "hide" the fact that it's a
> > python script, and look as much as possible like it's a
> > compiled program.
> > > The reason I don't just give my user a py file, is that I
> > don't want a cleaver user to change the innards of the script.
> > > On the other hand, I don't want to make a compiled
> > (freezed?) version of the application, because it'll grow the
> > resulting file significantly, and I don't have the experience
> > to know how it will run on different Linuxes.
> > > Bye,
> > > Ron.
>
> Hi Dave,
>
> > Most of the other answers basically paraphrased my suggestion
> > of making a wrapper file, not compiling it, and making it
> > executable. ?With that
> > approach, the user just types ? "wrapper.py" on his command line.
>
> > And wrapper.py only needs two lines, a shebang, and an
> > import, no big deal if the user modifies it. ?The rest of
> > your code can be .pyc files.
>
> > Steven makes some good points. ?You have to define what level
> > of clever you're protecting from. ?A determined hacker will
>
> The clever I try to guard against is not at hacker level, just the curios worker.
>
> > get in no matter what you do, unless you want to ship the
> > program in a proprietary embedded system, encased in epoxy. ?
> > Further, if you have an extension of .py or .pyc, a
> > knowledgeable hacker will know it's probably python.
>
> Granted, but the user will know that from the user manual anyway :-)
>
>
>
> > You imply you want it to run unmodifed on multiple unknown
> > Linux versions. ?I think that lets out binfmt solutions. ?
>
> Actually, no: I know the set of Linuxes my users are likely to have.
>
> > That means you need to test and support not only multiple
> > Linux implementations, but multiple Python versions, because
> > who knows what the user may have installed. ?I think you need
> > to rethink your support strategy. ?And maybe concentrate on
> > being able to detect change, rather than prevent it.
>
> > DaveA
>
> Thanks for the helpful suggestions.
> Ron.

how can a compiled python file (pyc) can defend your code against
clever-user? Try command cat "yourcode.pyc" and you will is how
"hardly" it can be read or modified :).
The most easy way how to distribute such file is with some shell batch
containing
#!/usr/bin/sh
python ./lib/myscript.pyc

the topology of the app would be a shell script called simply run, or
name of your app and something like that and a folder called lib where
your pyc file is stored, just make the script executable (chmod a+x
shellfile or chmod 755 shellfile) and force ppl to use it instead of
the pyc file in the lib folder :)


From masklinn at masklinn.net  Fri Jul 31 09:39:47 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 15:39:47 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a72edca$0$32755$426a74cc@news.free.fr>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>	<008e82e8$0$9756$c3e8da3@news.astraweb.com>	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<mailman.4041.1249042752.8015.python-list@python.org>
	<4a72edca$0$32755$426a74cc@news.free.fr>
Message-ID: <CBC838D8-3977-4DA4-8CBF-506F2E9A3B8E@masklinn.net>

On 31 Jul 2009, at 15:12 , Bruno Desthuilliers wrote:
> Masklinn a ?crit :
>> On 31 Jul 2009, at 13:38 , Bruno Desthuilliers wrote:
>>> Steven D'Aprano a ?crit :
>>>> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>>>> That and the fact that I couldn't stop laughing for long enough  
>>>>> to learn
>>>>> any more when I read in the Pragmatic Programmer's Guide that  
>>>>> "Ruby,
>>>>> unlike less flexible languages, lets you alter the value of a  
>>>>> constant."
>>>>> Yep, as they say "Bug" = "Undocumented feature"!
>>>> That's no different from Python's "constant by convention".
>>> Ruby's code blocks come from Smalltalk, where they are an absolute  
>>> necessity since message passing (which code blocks are part of) is  
>>> the *only* builtin control flow in Smalltalk - so you just *need*  
>>> this construction to provide branching and iterations.
>
[misunderstandings on my part/clarifications on yours]
>> Well it does at least allow for the creation of new flow control  
>> structures in library land when the existing ones aren't enough  
>> (e.g. allows Ruby not to require the introduction of a `with`  
>> statement).
>
> Yeps. But then other "traditionnal" control flow features become  
> redundant.
They can be anyway: Ruby doesn't deprecate most control flows as the  
actual usages of blocks are a bit restricted (cannot be used for  
`while` as it would require the serialization to a Proc, and Ruby's  
syntax doesn't allow sending multiple blocks to a method so `if?else`  
is out as well). And I assume they reintroduced the for?in sugar to  
ease the transition from more traditional languages (using #each and  
others seems the suggested collection iterators across the community).

From malc0de.encrypt at gmail.com  Fri Jul 31 09:43:49 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 06:43:49 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
	<7dg55pF2bfubpU1@mid.uni-berlin.de>
	<f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
	<72f851f9-a2d4-4448-900d-3fe20e4ebeb0@w41g2000yqb.googlegroups.com>
Message-ID: <c3afedd5-fb5b-43f3-99e9-fee23f8564d8@w41g2000yqb.googlegroups.com>

none of you can't interpret it ? do you have errors like me !?


From gary.wilson at gmail.com  Fri Jul 31 09:51:05 2009
From: gary.wilson at gmail.com (Gary Wilson)
Date: Fri, 31 Jul 2009 06:51:05 -0700 (PDT)
Subject: supported versions policy?
Message-ID: <07526890-6264-43c0-bd01-29ffdb3eedc2@d9g2000prh.googlegroups.com>

Does Python have a formal policy on the support lifetime (bug fixes,
security fixes, etc.) for major and minor versions?  I did a bit of
searching on the Python web site and this group, but didn't find
anything.  If there is a policy posted somewhere (and I just didn't
dig deep enough), would someone please point me in the right
direction.  If there is no posted policy, would someone be kind enough
to describe the practiced policy here.

I'm looking for is something like this:
http://docs.djangoproject.com/en/dev/internals/release-process/#supported-versions

Thanks,
Gary


From Scott.Daniels at Acm.Org  Fri Jul 31 09:51:17 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 31 Jul 2009 06:51:17 -0700
Subject: fast video encoding
In-Reply-To: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
References: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
Message-ID: <i8OdncfuALBtae_XnZ2dnUVZ_uSdnZ2d@pdx.net>

gregorth wrote:
> for a scientific application I need to save a video stream to disc for
> further post processing. My cam can deliver 8bit grayscale images with
> resolution 640x480 with a framerate up to 100Hz, this is a data rate
> of 30MB/s. Writing the data uncompressed to disc hits the data
> transfer limits of my current system and creates huge files. Therefore
> I would like to use video compression, preferably fast and high
> quality to lossless encoding. Final file size is not that important.
Well, it sounds like it better be enough to affect bandwidth.

> I am a novice with video encoding. I found that few codecs support
> gray scale images. Any hints to take advantage of the fact that I only
> have gray scale images?

You might try to see if there is a primitive .MNG encoder around.
That could give you lossless with perhaps enough compression to make
you happy, and I'm sure it will handle the grayscale.

.MNG is pictures only, but that doesn't hurt you in the least.

--Scott David Daniels
Scott.Daniels at Acm.Org


From roger.miller at nova-sol.com  Fri Jul 31 10:22:56 2009
From: roger.miller at nova-sol.com (Roger Miller)
Date: Fri, 31 Jul 2009 07:22:56 -0700 (PDT)
Subject: Test for Pythonwin?
References: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>
Message-ID: <7be1b318-851d-4197-afd4-48de38c878e6@d34g2000vbm.googlegroups.com>

On Jul 31, 2:09?am, "steve" <st... at nospam.au> wrote:
> Is there a good way to check if a script is running inside Pythonwin?
> Perhaps a property or method that is exposed by that environment?

I've used
  if sys.stdin.fileno() < 0:
This is not precisely a test for pythonwin, but indicates whether
standard streams are available, which is usually what I really
want to know.


From ethan at stoneleaf.us  Fri Jul 31 11:08:29 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 31 Jul 2009 08:08:29 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <008e82e8$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <4A7308ED.7040108@stoneleaf.us>

Steven D'Aprano wrote:
> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
> 
> 
>>That and the fact that I couldn't stop laughing for long enough to learn
>>any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>>unlike less flexible languages, lets you alter the value of a constant."
>>Yep, as they say "Bug" = "Undocumented feature"!
> 
> 
> That's no different from Python's "constant by convention". We don't even 
> get a compiler warning!
> 

That's quite different, actually.  Python doesn't claim to have 
constants!  Can't misinterpret what you can't have, can you?

[Holds breath while awaiting counter-example... :]

~Ethan~


From ethan at stoneleaf.us  Fri Jul 31 11:15:14 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 31 Jul 2009 08:15:14 -0700
Subject: Regexp problem
In-Reply-To: <4A72135E.7060205@mrabarnett.plus.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>	<mailman.3961.1248959276.8015.python-list@python.org>	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>	<h4s7pm$rgr$1@adenine.netfront.net>	<4A720AD5.1030202@stoneleaf.us>
	<4A72135E.7060205@mrabarnett.plus.com>
Message-ID: <4A730A82.3050502@stoneleaf.us>

MRAB wrote:
> Ethan Furman wrote:
> 
>> Marcus Wanner wrote:
>>> Wow, I really need to learn more about regexp...
>>> Any tutorials you guys can recommend?
>>>
>>> Marcus
>>
>>
>> Mastering Regular Expressions
>> Powerful Techniques for Perl and Other Tools
>> By Jeffrey E. F. Friedl
>>
>> Great book!
>>
> +1
> 
> I have the first edition, seventh printing (December 1998). It refers to
> the 'regex' module of Python 1.4b1, which was subsequently replaced by
> the current 're' module and then removed from the standard library. I
> hope it's been updated since then. :-)

I have the second edition (no idea which printing ;), and according to 
his preface it has indeed been much updated.  Most examples are in perl, 
the few in python are decent.  The knowledge embodied seems very 
thorough.  Since I've had the book (two weeks now?)  I've been able to 
solve two otherwise thorny issues using regular expressions.  Yay!

~Ethan~


From iainking at gmail.com  Fri Jul 31 11:35:45 2009
From: iainking at gmail.com (Iain King)
Date: Fri, 31 Jul 2009 08:35:45 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com> 
	<mailman.4048.1249052760.8015.python-list@python.org>
Message-ID: <c30eb377-49e0-4c1c-b9be-151704626b9d@b14g2000yqd.googlegroups.com>

On Jul 31, 4:08?pm, Ethan Furman <et... at stoneleaf.us> wrote:
> Steven D'Aprano wrote:
> > On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>
> >>That and the fact that I couldn't stop laughing for long enough to learn
> >>any more when I read in the Pragmatic Programmer's Guide that "Ruby,
> >>unlike less flexible languages, lets you alter the value of a constant."
> >>Yep, as they say "Bug" = "Undocumented feature"!
>
> > That's no different from Python's "constant by convention". We don't even
> > get a compiler warning!
>
> That's quite different, actually. ?Python doesn't claim to have
> constants! ?Can't misinterpret what you can't have, can you?
>
> [Holds breath while awaiting counter-example... :]
>
> ~Ethan~

The convention being detailed in PEP8: http://www.python.org/dev/peps/pep-0008/
basically, anything in ALL_CAPS is a constant, assuming you follow
those style guidelines.

Iain


From benjamin.kaplan at case.edu  Fri Jul 31 11:52:37 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Fri, 31 Jul 2009 11:52:37 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <c30eb377-49e0-4c1c-b9be-151704626b9d@b14g2000yqd.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<mailman.4048.1249052760.8015.python-list@python.org>
	<c30eb377-49e0-4c1c-b9be-151704626b9d@b14g2000yqd.googlegroups.com>
Message-ID: <ec96e1390907310852u4b905e1dld764d6579528cc23@mail.gmail.com>

On Fri, Jul 31, 2009 at 11:35 AM, Iain King<iainking at gmail.com> wrote:
> On Jul 31, 4:08?pm, Ethan Furman <et... at stoneleaf.us> wrote:
>> Steven D'Aprano wrote:
>> > On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>
>> >>That and the fact that I couldn't stop laughing for long enough to learn
>> >>any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>> >>unlike less flexible languages, lets you alter the value of a constant."
>> >>Yep, as they say "Bug" = "Undocumented feature"!
>>
>> > That's no different from Python's "constant by convention". We don't even
>> > get a compiler warning!
>>
>> That's quite different, actually. ?Python doesn't claim to have
>> constants! ?Can't misinterpret what you can't have, can you?
>>
>> [Holds breath while awaiting counter-example... :]
>>
>> ~Ethan~
>
> The convention being detailed in PEP8: http://www.python.org/dev/peps/pep-0008/
> basically, anything in ALL_CAPS is a constant, assuming you follow
> those style guidelines.
>

Right, but that's a style guide and not a language definition. Nobody
claims that anything in there is a part of the language.

> Iain
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 11:55:43 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 15:55:43 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
Message-ID: <008eef29$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 13:38:56 +0200, Bruno Desthuilliers wrote:

>> On the other hand, we don't have to prefix names with @ and @@,
> 
> Nope, we have to prefix them with 'self' or 'cls' (or even
> 'self.__class__').

Incorrect.

>>> class K:
...     class_attribute = 'No @@ required.'
...
>>> K().class_attribute
'No @@ required.'


No 'self' or 'cls' in sight.


I can see a vague advantage to using @ to create instance attributes and 
@@ to creating class attributes -- it makes it easy to create class 
attributes inside a method without needing to do a double lookup. In 
Python terms:

def K:
    def method(self):
        self.__class__.attr = "Class attribute"

would be:

def K:
    def method(self):
        @@attr = "Class attribute"

Advantages: you save a few characters and (possibly!) a couple of runtime 
lookups.

Disadvantages: your code is filled with line noise. It's an arbitrary 
choice between @@ meaning instance attribute and @@ meaning class 
attribute -- there's no logical reason for choosing one over the other, 
so you have to memorise which is which. It's easy to get it wrong.

'self' and 'cls' at least are words, even if 'cls' is badly misspelled :)



>> and we
>> don't have the compiler trying to *guess* whether we're calling a
>> function or referring to a variable.
> 
> Please re-read a bit more carefully - it's *all* method call. 

What did I misread from here?

[quote]
When Ruby sees a name such as ``a'' in an expression, it needs to 
determine if it is a local variable reference or a call to a method with 
no parameters. To decide which is the case, Ruby uses a heuristic. As 
Ruby reads a source file, it keeps track of symbols that have been 
assigned to. It assumes that these symbols are variables. When it 
subsequently comes across a symbol that might be either a variable or a 
method call, it checks to see if it has seen a prior assignment to that 
symbol. If so, it treats the symbol as a variable; otherwise it treats it 
as a method call.
[end quote]

And see the example "pathological case" comparing a function call (not 
method) and a variable.

http://ruby-doc.org/docs/ProgrammingRuby/html/language.html


> Python is
> 'uniform' in obj.name is always an attribute lookup (methods being
> attributes), Ruby is uniform in that 'obj.name' is always a method call.

Which would be relevant if I was talking about method calls, but I wasn't.



>> Somebody who knows more Ruby than me should try writing the Zen of
>> Ruby. Something like:
> 
> (snip childish parody of Python Zen)
> 
> Steven, is that any useful ?

It made me feel good.

But seriously, while I admit that I have very little Ruby experience, and 
so aren't in a great position to judge, it seems to me that Ruby doesn't 
have anything like Python's over-riding design principles (the Zen). If 
there is a design principle to Ruby, I can't see what it is.

I'm the first to admit that I'm far too inexperienced with the language 
to make this a fair judgement. Unfair it might be, but it doesn't 
necessarily mean I'm wrong! *wink*

Ruby just seems to be far more complicated than Python: things which 
Python does at runtime, with a function call, Ruby has special syntax for:

"a bunch of words".split()
%w(a bunch of words)

ord('a')
?a

That makes the barrier to entry far higher: it's easier to leverage 
existing knowledge to interpret unfamiliar Python code than unfamiliar 
Ruby code. Or so it seems to me.

Oh, and I admit that Python decorators are a conspicuous counter-example. 
I wouldn't do without them, but neither would I expect somebody to intuit 
what they do.


>> Although I'm sure Ruby has its good points. I'm not convinced anonymous
>> code blocks are one of them though.
> 
> Ruby's code blocks come from Smalltalk, where they are an absolute
> necessity since message passing (which code blocks are part of) is the
> *only* builtin control flow in Smalltalk - so you just *need* this
> construction to provide branching and iterations.

Just because Smalltalk had a particular (mis?)feature doesn't mean that 
other languages should copy it. I know, I know, Ruby people swear by 
anonymous code blocks, and I've read Paul Graham too. But I'm really not 
so sure that the benefits of anonymous code blocks are great enough to 
overcome the disadvantages of anonymous code blocks.


> Wether it makes sense to have code blocks in Ruby is another question
> since Ruby does provide traditional control flow features, but then one
> could question Python's "lambda" (hem...) too.

lambda, by allowing the function to be only a single expression, doesn't 
suffer the disadvantages of anonymous code blocks. lambda, by allowing 
the function to be only a single expression, also has fewer advantages 
than anonymous code blocks. I think lambda ends up on the "more 
advantages than disadvantages" side. I'm keeping my mind open regarding 
Ruby code blocks.



-- 
Steven


From masklinn at masklinn.net  Fri Jul 31 12:15:15 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 18:15:15 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <008eef29$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<008eef29$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <11938EF7-4FC3-4F1A-A665-D9360442456F@masklinn.net>

On 31 Jul 2009, at 17:55 , Steven D'Aprano wrote:
> But seriously, while I admit that I have very little Ruby  
> experience, and
> so aren't in a great position to judge, it seems to me that Ruby  
> doesn't
> have anything like Python's over-riding design principles (the Zen).  
> If
> there is a design principle to Ruby, I can't see what it is.
>
As far as I know, Ruby doesn't have anything like the Zen no. But then  
again, I don't know any language other than Python with such a document.

> Ruby just seems to be far more complicated than Python: things which
> Python does at runtime, with a function call, Ruby has special  
> syntax for:
>
> "a bunch of words".split()
> %w(a bunch of words)
>
> ord('a')
> ?a
>
That's the Perl heritage. And since it inherits from Perl, TIMTOWTDI:
     >> "a bunch of words".split
     => ["a", "bunch", "of", "words"]
     >> "a"[0]
     => 97
(yes, the indexing operator returns a character code if provided a  
single index. With two, it returns as string slice)

Oh and %w() isn't really equivalent to split(): you don't use it to  
split a string but to create a list of strings, so the equivalent  
expression in Python would be `["a", "bunch", "of", "words"]`.

> That makes the barrier to entry far higher: it's easier to leverage
> existing knowledge to interpret unfamiliar Python code than unfamiliar
> Ruby code. Or so it seems to me.
>
That's probable.

>>> Although I'm sure Ruby has its good points. I'm not convinced  
>>> anonymous
>>> code blocks are one of them though.
>>
>> Ruby's code blocks come from Smalltalk, where they are an absolute
>> necessity since message passing (which code blocks are part of) is  
>> the
>> *only* builtin control flow in Smalltalk - so you just *need* this
>> construction to provide branching and iterations.
>
> Just because Smalltalk had a particular (mis?)feature doesn't mean  
> that
> other languages should copy it. I know, I know, Ruby people swear by
> anonymous code blocks, and I've read Paul Graham too. But I'm really  
> not
> so sure that the benefits of anonymous code blocks are great enough to
> overcome the disadvantages of anonymous code blocks.
>
What are the disadvantages of anonymous functions?



From tjreedy at udel.edu  Fri Jul 31 12:24:28 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 12:24:28 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
Message-ID: <h4v5rr$hrn$1@ger.gmane.org>

Masklinn wrote:

> #each is simply a method that takes a function (called blocks in ruby). 
> One could call it a higher-order method I guess.
> 
> It's an implementation of the concept of internal iteration: instead of 
> collections yielding iterator objects, and programmers using those 
> through specially-built iteration constructs (e.g. `for?in`), 
> collections control iteration over themselves (the iteration is 
> performed "inside" the collection, thus the "internal" part) and the 
> programmer provides the operations to perform at each iterative step 
> through (usually) a function.

Python's iterator protocol was developed in part to avoid the 
(inside-out) callback style of programming. Writing virtual collections 
as generator functions instead of iterator or iterable classes saves a 
lot of boilerplate code. The itertools modules shows how nicely 
iterators can be composed in a way that is much more awkward with callbacks.

> In Python (assuming we had anonymous defs and an each method on lists), 
> the following loop:
> 
>     for item in some_list:
>         do_something(item)
>         do_something_else(item)
> 
>     some_list.each((def (item):
>         do_something(item)
>         do_something_else(item)
>     ))

And how does Ruby do the equivalent of

def double(it):
   for i in it:
     yield 2*i

for i,j in zip(double(some_list), some_gen_func(args)):
   print(do_something(i+j,i-j))

Terry Jan Reedy



From bdezonia at wisc.edu  Fri Jul 31 12:33:45 2009
From: bdezonia at wisc.edu (BDZ)
Date: Fri, 31 Jul 2009 09:33:45 -0700 (PDT)
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
	<3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>
Message-ID: <337482f9-8ad9-4600-9cf4-39911f5368ac@h31g2000yqd.googlegroups.com>

On Jul 30, 4:41?pm, Lo?c Domaign? <loic.domai... at googlemail.com>
wrote:
> Hi,
>
> > Hello. I have written a Python 3.1 script running on Windows that uses
> > os.path.exists() to connect to network shares. If the various network
> > shares require different user account and password combos than the
> > account the script is running under the routine returns false. I need
> > something like os.samba.path.exists(username,password,path). Does
> > anyone have a suggestion on how I can accomplish what I need to do in
> > Python?
>
> Could the Python Samba module PySamba be interesting for you?http://sourceforge.net/projects/pysamba/
>
> HTH,
> Lo?c
> --
> My blog:http://www.domaigne.com/blog

Unfortunately, although it has the calls I'd want, pysamba appears to
be *nix only. I need something that will work under Windows. Is there
a set of Python Windows functions (official or contributed) that might
do what I need? (I'm new to Python)


From darkneter at gmail.com  Fri Jul 31 12:35:10 2009
From: darkneter at gmail.com (NighterNet)
Date: Fri, 31 Jul 2009 09:35:10 -0700 (PDT)
Subject: threads check socket
Message-ID: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>

I been trying to find a way to check the socket is open or not. The
thread are in a group and loop if the sockets are open. If they are
not open delete the thread and remove the group. I need on this.


From tjreedy at udel.edu  Fri Jul 31 12:39:21 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 12:39:21 -0400
Subject: supported versions policy?
In-Reply-To: <07526890-6264-43c0-bd01-29ffdb3eedc2@d9g2000prh.googlegroups.com>
References: <07526890-6264-43c0-bd01-29ffdb3eedc2@d9g2000prh.googlegroups.com>
Message-ID: <h4v6no$kd6$1@ger.gmane.org>

Gary Wilson wrote:
> Does Python have a formal policy on the support lifetime (bug fixes,
> security fixes, etc.) for major and minor versions?  I did a bit of
> searching on the Python web site and this group, but didn't find
> anything.  If there is a policy posted somewhere (and I just didn't
> dig deep enough), would someone please point me in the right
> direction.  If there is no posted policy, would someone be kind enough
> to describe the practiced policy here.

Defining Pyx.y.z as Pymajor.minor.bugfix, the last normal bugfix comes 
out about the same time as the next minor. True security fixes (very 
rare) come out for a couple of years thereafter. (Exception, 3.0 support 
ended with 3.0.1 -- it should be replaced with 3.1.) Currently Py2 and 
Py3 are running in parallel. The future 2.7.z's will probably be the end 
of the Py2 series. Everything is contingent on voluteer time to do the 
above.

tjr



From db3l.net at gmail.com  Fri Jul 31 12:40:34 2009
From: db3l.net at gmail.com (David Bolen)
Date: Fri, 31 Jul 2009 12:40:34 -0400
Subject: fast video encoding
References: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
Message-ID: <m2y6q43iwt.fsf@valheru.db3l.homeip.net>

gregorth <gregor.thalhammer at gmail.com> writes:

> I am a novice with video encoding. I found that few codecs support
> gray scale images. Any hints to take advantage of the fact that I only
> have gray scale images?

I don't know that there's any good way around the fact that video
encoding is simply one of the heavier CPU-bound activities you're
likely to encounter.  So I suspect that codec choice (barring letting
quality drop a bit) is going to move the bar less than picking the
beefiest CPU you can.

If I were looking to do this, I'd probably include investigating
pumping the raw camera images into an ffmpeg encoding subprocess and
let it handle all the encoding.  There's about a gazillion options and
a variety of codec options to play with for performance.  You could
grab and store a short video sample from the camera and use it as a
benchmark to compare encoding options.

ffmpeg does have a -pix_fmt option that can be used to indicate the
input pixel type - "gray" would be 8-bit, and result in a 4:0:0 image
with a YUV-based encoder, for example.  Not sure how much, if any,
impact it would have on encoding speed though.

To be honest, with your data rate, I might even consider getting
Python out of the pure encoding path once it starts - depending on the
raw network format delivered by the camera you might be able to have
ffmpeg read directly from it.  Might not be worth it, since the data
transfer is probably I/O bound, but a 640x480x1 stream at 100Hz is
still nothing to sniff at, and even managing the raw data flow in
Python might eat up some CPU that you could better allocate to the
encoding process, or require extra data copies along the way that
would be best to avoid.

-- David


From garrickp at gmail.com  Fri Jul 31 12:53:44 2009
From: garrickp at gmail.com (Falcolas)
Date: Fri, 31 Jul 2009 09:53:44 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net> 
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net> 
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com> 
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com> 
	<mailman.4036.1249033777.8015.python-list@python.org>
Message-ID: <5028a8b0-21b6-4052-8483-7236b9142bd9@h21g2000yqa.googlegroups.com>

On Jul 31, 3:49?am, Masklinn <maskl... at masklinn.net> wrote:
> On 31 Jul 2009, at 10:25 , Chris Rebert wrote:> On Fri, Jul 31, 2009 at 1:21 AM, Xavier Ho<cont... at xavierho.com> ?
> > wrote:
> >> On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <maskl... at masklinn.net> ?
> >> wrote:
>
> >>> <snip>... but since Python doesn't have anonymous functions that ?
> >>> usage
> >>> tends to be a bit too verbose ... <snip>
>
> >> Sorry to interrupt, but wouldn't lambda in Python be considered as
> >> 'anonymous functions'?
>
> > I believe "full" anonymous functions was intended by the author.
> > lambdas are limited to a single expression.
>
> Yes, and they're limited to a single *expression*, so before Python 3, ?
> lambda: print "foo" is out. Likewise, it isn't possible to have an if/
> else statement within a lambda (though a ternary is ok), or a with, ? ?
> since Python statements aren't expressions.

Perhaps you can't do lambda foo: print foo, but you *can* do lambda x:
sys.stdout.write(x).

Combined with the ternary if, it seem sufficient if you want to stick
to the ideal "Simple is better than Complex". Sure, with statements
allowed in anonymous functions, you can save on a line of typing (def
blargh(x):), but I don't feel the obfuscation is worth the cost.

~G


From digitig at gmail.com  Fri Jul 31 12:54:23 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 31 Jul 2009 17:54:23 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <008e82e8$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>

2009/7/31 Steven D'Aprano <steve at remove-this-cybersource.com.au>:
> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>
>> That and the fact that I couldn't stop laughing for long enough to learn
>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>> unlike less flexible languages, lets you alter the value of a constant."
>> Yep, as they say "Bug" = "Undocumented feature"!
>
> That's no different from Python's "constant by convention". We don't even
> get a compiler warning!

We don't actually *declare* that something is constant and then have
that declaration ignored. Python doesn't lie to us, although (as in
any language) a programmer might.

-- 
Tim Rowe


From jabronson at gmail.com  Fri Jul 31 13:02:55 2009
From: jabronson at gmail.com (Joshua Bronson)
Date: Fri, 31 Jul 2009 10:02:55 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<86skgr0yjn.fsf@gmail.com>
	<pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au> 
	<Xns9C5082EB1B123duncanbooth@127.0.0.1>
Message-ID: <ec98fc01-4a2e-4c7b-9155-9e37e1b91151@g25g2000vbr.googlegroups.com>

On Jul 22, 7:55?am, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> I find it interesting that the heapq functions tell you in the
> documentation that they aren't suitable for use where n==1 or where n is
> near the total size of the sequence whereas random.sample() chooses what it
> thinks is the best algorithm based on the input. At the very least I would
> have thought the heapq functions could check for n==1 and call min/max when
> it is.

I've had the same thought myself a number of times, so I filed a bug:
http://bugs.python.org/issue6614


From marcusw at cox.net  Fri Jul 31 13:22:24 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 31 Jul 2009 13:22:24 -0400
Subject: threads check socket
In-Reply-To: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
Message-ID: <h4v98g$25dt$1@adenine.netfront.net>

On 7/31/2009 12:35 PM, NighterNet wrote:
> I been trying to find a way to check the socket is open or not. The
> thread are in a group and loop if the sockets are open. If they are
> not open delete the thread and remove the group. I need on this.
Being a bit more specific would help.

Are you using tcp or udp? Is it a local socket or a remote one? What is 
controlling the socket? Define "open".

Marcus


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 13:23:02 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 14:23:02 -0300
Subject: threads check socket
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
Message-ID: <op.uxxzworex6zn5v@gabriel.sleipnir-bsas>

En Fri, 31 Jul 2009 13:35:10 -0300, NighterNet <darkneter at gmail.com>  
escribi?:

> I been trying to find a way to check the socket is open or not. The
> thread are in a group and loop if the sockets are open. If they are
> not open delete the thread and remove the group. I need on this.

What means an "open socket"? Do you want to detect whether the other side  
closed the connection? In that case reading from the socket returns an  
empty string.

Regarding the "threads in a group", I don't understand what you mean. But  
in general, you don't delete a thread, you just return from its run()  
method and the thread finishes execution.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 13:32:13 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 14:32:13 -0300
Subject: file comparison
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <op.uxx0bzg2x6zn5v@gabriel.sleipnir-bsas>

En Fri, 31 Jul 2009 06:25:17 -0300, learner learner <pyvault2.6 at gmail.com>  
escribi?:

> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a third
> file or overwrite into one of them.

Look at the difflib module: http://docs.python.org/library/difflib.html

If that's not what you want, you have to provide much more details.

-- 
Gabriel Genellina



From python at rcn.com  Fri Jul 31 13:32:46 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 10:32:46 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<86skgr0yjn.fsf@gmail.com>
	<pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au> 
	<Xns9C5082EB1B123duncanbooth@127.0.0.1>
Message-ID: <b8857b9d-fbd6-48b3-b33b-d824829368fc@k13g2000prh.googlegroups.com>

On Jul 22, 4:55?am, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> Steven D'Aprano <ste... at REMOVE.THIS.cybersource.com.au> wrote:
> > But that's the wrong solution to the problem. The OP wants the largest
> > (or smallest) item, which he expects to get by sorting, then grabbing
> > the first element:
>
> > sorted(alist)[0]
>
> > That requires sorting the entire list, only to throw away everything
> > except the first item. A better solution is to use min() and max(),
> > neither of which sort the list, so they are much faster.
>
> And if they want the n smallest or largest items (where n is significantly
> less than the length of the list[*]) they might consider using
> heapq.nsmallest() and heapq.nlargest()
>
> I find it interesting that the heapq functions tell you in the
> documentation that they aren't suitable for use where n==1 or where n is
> near the total size of the sequence whereas random.sample() chooses what it
> thinks is the best algorithm based on the input. At the very least I would
> have thought the heapq functions could check for n==1 and call min/max when
> it is.

The heapq.py code in Py2.7 and Py3.1 already does some automatic
algorithm selection:
http://svn.python.org/view/python/branches/release31-maint/Lib/heapq.py?revision=73579&view=markup

The automatic seletion of alternatives only occurs in clear-cut cases
(such as n==1
or where n==len(iterable) when the iterable has a known length).   For
the
remaining cases, the switchover point from heapq to sorted needs a
programmer's judgment based on whether the input iterable has a known
length, the cost of comparison function, and whether input is already
partially ordered.

The advice in the docs helps the reader understand the
relationships between min, max, nsmallest, nlargest, and sorted.


Raymond


From ethan at stoneleaf.us  Fri Jul 31 13:41:15 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 31 Jul 2009 10:41:15 -0700
Subject: .dbf tables and Null
Message-ID: <4A732CBB.9090400@stoneleaf.us>

Mornin'!  and a good one, too, I hope.

Question for you...

First part of the question:  What is the general value in having Null 
capability for fields?

Second part:  Is there a tangible difference between Null, and the 
nothing of 0, '', False, etc, in python?

Third part:  If there is a tangible difference, do those of us who use 
python and these old, refuse-to-die, .dbf files actually have need of, 
or have tables including, Null values?

P.S. part (for John Machin, if he sees this  ;)
Will the dbf package you are working on support Null values?

Any and all information appreciated!

~Ethan~


From darkneter at gmail.com  Fri Jul 31 13:42:29 2009
From: darkneter at gmail.com (NighterNet)
Date: Fri, 31 Jul 2009 10:42:29 -0700 (PDT)
Subject: threads check socket
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
	<mailman.4055.1249061007.8015.python-list@python.org>
Message-ID: <7b3247b0-4c85-4290-9de2-41fc45348d3d@z4g2000prh.googlegroups.com>

On Jul 31, 10:23?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Fri, 31 Jul 2009 13:35:10 -0300, NighterNet <darkne... at gmail.com> ?
> escribi?:
>
> > I been trying to find a way to check the socket is open or not. The
> > thread are in a group and loop if the sockets are open. If they are
> > not open delete the thread and remove the group. I need on this.
>
> What means an "open socket"? Do you want to detect whether the other side ?
> closed the connection? In that case reading from the socket returns an ?
> empty string.
>
> Regarding the "threads in a group", I don't understand what you mean. But ?
> in general, you don't delete a thread, you just return from its run() ?
> method and the thread finishes execution.
>
> --
> Gabriel Genellina

Thread added into the array. Well this thread when user leave the
server want to make sure it not in used so that I can reuse it some
how or move into another array.

Need to know the thread speed that need for game server timer to
control it. Don't want it too fast or slow for the game server.
fps = 30
	def run(self):
		while True:
			self.gametime += 1
			if self.gametime > 10000000/fps:
				self.gametime = 0;


From jabronson at gmail.com  Fri Jul 31 13:44:33 2009
From: jabronson at gmail.com (Joshua Bronson)
Date: Fri, 31 Jul 2009 10:44:33 -0700 (PDT)
Subject: heapq "key" arguments
Message-ID: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>

According to http://docs.python.org/library/heapq.html, Python 2.5
added an optional "key" argument to heapq.nsmallest and
heapq.nlargest. I could never understand why they didn't also add a
"key" argument to the other relevant functions (heapify, heappush,
etc). Say I want to maintain a heap of (x, y) pairs sorted only by
first coordinate. Without being able to pass key=itemgetter(0), won't
heapifying a list of such pairs unnecessarily compare both
coordinates? And worse, if the second coordinate is actually an object
with no ordering defined for it, heapifying will cause an error even
though all I care about is sorting by the first coordinate, which does
have an ordering. Am I missing something?


From python at rcn.com  Fri Jul 31 13:49:04 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 10:49:04 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>

On Jul 20, 9:27?am, Phillip B Oldham <phillip.old... at gmail.com> wrote:
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.

The underlying C code for the two is substantially the same.  In terms
of code, tuples are in effect just immutable lists that have the
added
feature of being hashable (and therefore usable as dictionary keys or
elements of sets).

Beyond the mutable/hashable distinction, there is an important
philosophical distinction articulated by Guido.  He deems tuples
to be useful for struct like groupings of non-homogenous fields
and lists to be useful for sequences of homogenous data suitable
for looping.

While nothing in the list/tuple code requires you to make that
distinction,
it is important because that philosophy pervades the language.  If you
follow Guido's direction, you'll find that the various parts of the
language fit together better.  Do otherwise and you'll be going
against
the grain.


Raymond

P.S.  The C code for lists and tuples have a slightly difference
internal
structure that makes tuples a little more space efficient (since their
size is known at the outset and doesn't change during use).


From jgardner at jonathangardner.net  Fri Jul 31 14:02:48 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Fri, 31 Jul 2009 11:02:48 -0700 (PDT)
Subject: heapq "key" arguments
References: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>
Message-ID: <1582f82e-34aa-4b66-b989-c9f8351a5f1c@o9g2000prg.googlegroups.com>

On Jul 31, 10:44?am, Joshua Bronson <jabron... at gmail.com> wrote:
> Say I want to maintain a heap of (x, y) pairs sorted only by
> first coordinate. Without being able to pass key=itemgetter(0), won't
> heapifying a list of such pairs unnecessarily compare both
> coordinates?

It will compare the second value only if the first values are equal.


From bfrederi at library.unt.edu  Fri Jul 31 14:08:44 2009
From: bfrederi at library.unt.edu (Brandon Fredericks)
Date: Fri, 31 Jul 2009 11:08:44 -0700 (PDT)
Subject: base64 Incorrect Padding
Message-ID: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>

I did a search within this group, but couldn't find any information on
this.

I am sending base64 encoded data as the content over http using
urllib2 urlopen. When I receive the data and attempt to decode it, I
get an "Incorrect Padding" error. Is there a simple way to fix this? A
better way to send and receive the data possibly (using base64 of
course)?


From masklinn at masklinn.net  Fri Jul 31 14:15:09 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 20:15:09 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <h4v5rr$hrn$1@ger.gmane.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<h4v5rr$hrn$1@ger.gmane.org>
Message-ID: <003A7A2F-0FF1-42D4-96ED-1EBBA605B475@masklinn.net>

On 31 Jul 2009, at 18:24 , Terry Reedy wrote:
> Masklinn wrote:
>
>> #each is simply a method that takes a function (called blocks in  
>> ruby). One could call it a higher-order method I guess.
>> It's an implementation of the concept of internal iteration:  
>> instead of collections yielding iterator objects, and programmers  
>> using those through specially-built iteration constructs (e.g. `for? 
>> in`), collections control iteration over themselves (the iteration  
>> is performed "inside" the collection, thus the "internal" part) and  
>> the programmer provides the operations to perform at each iterative  
>> step through (usually) a function.
>
> Python's iterator protocol was developed in part to avoid the  
> (inside-out) callback style of programming. Writing virtual  
> collections as generator functions instead of iterator or iterable  
> classes saves a lot of boilerplate code. The itertools modules shows  
> how nicely iterators can be composed in a way that is much more  
> awkward with callbacks.
>
>> In Python (assuming we had anonymous defs and an each method on  
>> lists), the following loop:
>>    for item in some_list:
>>        do_something(item)
>>        do_something_else(item)
>>    some_list.each((def (item):
>>        do_something(item)
>>        do_something_else(item)
>>    ))
>
> And how does Ruby do the equivalent of
>
> def double(it):
>  for i in it:
>    yield 2*i
>
> for i,j in zip(double(some_list), some_gen_func(args)):
>  print(do_something(i+j,i-j))


Somethign along the lines of

     some_list.map{|e| 2*e}.zip(some_gen_func(args)).each {|i, j|
         puts(do_something(i+j, i-j))
     }

The `#each` call after `#zip` is not actually necessary, but I find it  
clearer. Oh, and some_gen_func and do_something probably wouldn't work  
that way (as I said above, Ruby isn't big on named functions and  
doesn't actually have them)

From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 14:17:05 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 18:17:05 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<008eef29$0$9756$c3e8da3@news.astraweb.com>
	<mailman.4051.1249056929.8015.python-list@python.org>
Message-ID: <008f104b$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 18:15:15 +0200, Masklinn wrote:

> > I know, I know, Ruby people swear by
> > anonymous code blocks, and I've read Paul Graham too. But I'm really
> > not so sure that the benefits of anonymous code blocks are great
> > enough to overcome the disadvantages of anonymous code blocks.
> >
> What are the disadvantages of anonymous functions?

In no particular order, and not necessarily exhaustive:

* The risk of obfuscation in your code. That's fairly minimal for 
lambdas, because they're just a single expression, but for a large 
anonymous code block (ACB) defined inside a named function, it may be 
difficult for the reader to easily distinguish which bits are the outer 
function and which are the ACB.


* Loss of useful debugging information. Take this example from Python:

>>> def main(f):
...     return f(3)
...
>>> main(lambda n: 2/(n-3))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in main
  File "<stdin>", line 1, in <lambda>
ZeroDivisionError: integer division or modulo by zero
>>>
>>> def my_special_function(n):
...     return 2/(n-3)
...
>>> main(my_special_function)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in main
  File "<stdin>", line 2, in my_special_function
ZeroDivisionError: integer division or modulo by zero

If your code has only one anonymous function (whether a lambda or a full 
multi-line block), then it's easy to identify which lambda raised the 
exception: there is only one it could be. But if your code uses lots of 
lambdas, the lack of a function name makes it hard to distinguish one 
<lambda> from another <lambda>. Anonymity makes identification harder.


* Risk of code-duplication and breaking the principle of Once And Only 
Once. Anonymous functions are generally created, used, then immediately 
thrown away -- or at least made more-or-less inaccessible for reuse. An 
anonymous function stored in a callback still exists, but the coder isn't 
able to easily re-use it for another callback somewhere else in the code. 
Consequently, there's a temptation for the coder to write the same 
function multiple times:

add_button("Parrot", colour=blue, callback=lambda x: x.stuff('a'))
add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
add_button("Canary", colour=yellow, callback=lambda x: x.stuff('a'))

instead of:

def bird_callback(x):
    return x.stuff('a')

add_button("Parrot", colour=blue, callback=bird_callback)
add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
add_button("Canary", colour=yellow, callback=bird_callback)

* Recursion is more or less impossible without fragile tricks.

(At least for Python. I don't know how recursion operates in Ruby.)





-- 
Steven


From dciphercomputing at gmail.com  Fri Jul 31 14:22:26 2009
From: dciphercomputing at gmail.com (Simon)
Date: Fri, 31 Jul 2009 11:22:26 -0700 (PDT)
Subject: Newbie Question regarding __init__()
Message-ID: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>

Hi

I want to create an instance of dcCursor which inherits from
dcObject.  When I run the following code it gives the error shown.
Can some explain to me what is wrong? I have included the dcObject.py
and dcCursor.py below.

>>>import dcObject
>>> import dcCursor
>>> x = dcCursor.dcCursor()
Traceback (most recent call last):
  File "<interactive input>", line 1, in <module>
TypeError: __init__() takes no arguments (1 given)

# -*- coding: utf-8 -*-
# dcCursor.py - The base Cursor Class

from dcObject import dcObject

class dcCursor(dcObject):
    """The base Cursor Class"""
    def OpenCursor(tcTemp,tcTable):
        """Opens the specified cursor
        Parameters: tcTemp,tcTable"""
        pass

    def CreateCursor(tcTable):
        """Creates the specified cursor
        Parameters: tcTable"""
        pass

    def init_Exec():
        print("init_Exec called")



# -*- coding: utf-8 -*-
# dcObject.py - Base Object
class dcObject(object):
    """Base Object"""
    def __init__():
        """default init method has the form
        of init_Pre() and init_Exec
        init_Post()"""
        self.init_Pre() and self.init_Exec()
        self.init_Post()

    def init_Pre():
        """Always called before init_Exec()
        if it returns false init_Exec is
        not executed"""
        return True

    def init_Exec():
        """Base __init__ code goes here and this is
        only executed if init_Pre() returns true"""
        return True

    def init_Post():
        """Always called after the init_Pre() and
        init_Exec()"""
        return True



From nobody at nowhere.com  Fri Jul 31 14:22:33 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 31 Jul 2009 19:22:33 +0100
Subject: Printing with colors in a portable way
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
Message-ID: <pan.2009.07.31.18.22.32.640000@nowhere.com>

On Thu, 30 Jul 2009 15:40:37 -0700, Robert Dailey wrote:

> Anyone know of a way to print text in Python 3.1 with colors in a
> portable way? In other words, I should be able to do something like
> this:
> 
> print_color( "This is my text", COLOR_BLUE )
> 
> And this should be portable (i.e. it should work on Linux, Mac,
> Windows).

The way that terminals (and emulators) handle colour is fundamentally
different from the DOS/Windows console. If you want something which will
work on both, you will have write separate implementations for terminals
and the DOS/Windows console.

For terminals, you can use the "curses" package, e.g.:

import curses

curses.setupterm()
setaf = curses.tigetstr('setaf')
setab = curses.tigetstr('setab')

def foreground(num):
    if setaf:
        sys.stdout.write(curses.tparm(setaf, num))

def background(num):
    if setab:
        sys.stdout.write(curses.tparm(setab, num))

For the Windows console, you'll need to use ctypes to interface to the
SetConsoleTextAttribute() function from Kernel32.dll.



From python at mrabarnett.plus.com  Fri Jul 31 14:33:57 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 19:33:57 +0100
Subject: Newbie Question regarding __init__()
In-Reply-To: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
Message-ID: <4A733915.9020203@mrabarnett.plus.com>

Simon wrote:
> Hi
> 
> I want to create an instance of dcCursor which inherits from
> dcObject.  When I run the following code it gives the error shown.
> Can some explain to me what is wrong? I have included the dcObject.py
> and dcCursor.py below.
> 
>>>> import dcObject
>>>> import dcCursor
>>>> x = dcCursor.dcCursor()
> Traceback (most recent call last):
>   File "<interactive input>", line 1, in <module>
> TypeError: __init__() takes no arguments (1 given)
> 
All instance methods must have the instance as the first argument, by
convention called 'self':

> # -*- coding: utf-8 -*-
> # dcCursor.py - The base Cursor Class
> 
> from dcObject import dcObject
> 
> class dcCursor(dcObject):
>     """The base Cursor Class"""
>     def OpenCursor(tcTemp,tcTable):
     def OpenCursor(self, tcTemp, tcTable):

>         """Opens the specified cursor
>         Parameters: tcTemp,tcTable"""
>         pass
> 
>     def CreateCursor(tcTable):
     def CreateCursor(self, tcTable):
...

and so on, including the '__init__' method.


From emmanuel.surleau at gmail.com  Fri Jul 31 14:41:12 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 20:41:12 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>
Message-ID: <200907312041.12241.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 18:54:23 Tim Rowe wrote:
> 2009/7/31 Steven D'Aprano <steve at remove-this-cybersource.com.au>:
> > On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
> >> That and the fact that I couldn't stop laughing for long enough to learn
> >> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
> >> unlike less flexible languages, lets you alter the value of a constant."
> >> Yep, as they say "Bug" = "Undocumented feature"!
> >
> > That's no different from Python's "constant by convention". We don't even
> > get a compiler warning!
>
> We don't actually *declare* that something is constant and then have
> that declaration ignored. Python doesn't lie to us, although (as in
> any language) a programmer might.

You could say that Ruby doesn't either, you just need to read the 
documentation. Ruby's unwritten motto is "flexibility ?ber alles". In this 
regard, it is consistent (1). Not much is really bolted down in Ruby. You get 
encapsulation, but it's so easy to break that it's mostly symbolic. It's a 
language which gives great power to the programmer. Whether Ruby programmers 
handle this power responsibly is another debate.

Cheers,

Emm

(1) I find Ruby to be pretty consistent in general, which is not always the 
case of Python.


From emmanuel.surleau at gmail.com  Fri Jul 31 14:48:03 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 20:48:03 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
Message-ID: <200907312048.03922.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 19:49:04 Raymond Hettinger wrote:
> On Jul 20, 9:27 am, Phillip B Oldham <phillip.old... at gmail.com> wrote:
> > Specifically the "differences" between lists and tuples have us
> > confused and have caused many "discussions" in the office. We
> > understand that lists are mutable and tuples are not, but we're a
> > little lost as to why the two were kept separate from the start. They
> > both perform a very similar job as far as we can tell.
>
> The underlying C code for the two is substantially the same.  In terms
> of code, tuples are in effect just immutable lists that have the
> added
> feature of being hashable (and therefore usable as dictionary keys or
> elements of sets).
>
> Beyond the mutable/hashable distinction, there is an important
> philosophical distinction articulated by Guido.  He deems tuples
> to be useful for struct like groupings of non-homogenous fields
> and lists to be useful for sequences of homogenous data suitable
> for looping.
>
> While nothing in the list/tuple code requires you to make that
> distinction,
> it is important because that philosophy pervades the language.  If you
> follow Guido's direction, you'll find that the various parts of the
> language fit together better.  Do otherwise and you'll be going
> against
> the grain.

I might be wrong, but I get the impression that many people don't indeed "get 
it" and use tuples as static arrays and lists when the array needs to be 
dynamically resized. This is certainly how I use them as well.

This would tend to show that Guido's notion here was not particularly 
intuitive.

Cheers,

Emm


From __peter__ at web.de  Fri Jul 31 14:56:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 20:56:15 +0200
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
Message-ID: <h4veod$n9l$01$1@news.t-online.com>

Brandon Fredericks wrote:

> I did a search within this group, but couldn't find any information on
> this.
> 
> I am sending base64 encoded data as the content over http using
> urllib2 urlopen. When I receive the data and attempt to decode it, I
> get an "Incorrect Padding" error. Is there a simple way to fix this? A
> better way to send and receive the data possibly (using base64 of
> course)?

Have the server send some known data. Read it with urllib2.urlopen(). 
Compare with that same data that you encoded locally. What are the 
differences?

Peter




From masklinn at masklinn.net  Fri Jul 31 15:24:33 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 21:24:33 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <008f104b$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<008eef29$0$9756$c3e8da3@news.astraweb.com>
	<mailman.4051.1249056929.8015.python-list@python.org>
	<008f104b$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <A07CE303-587E-400E-9BBC-267CD0C5FB0E@masklinn.net>

On 31 Jul 2009, at 20:17 , Steven D'Aprano wrote:
> On Fri, 31 Jul 2009 18:15:15 +0200, Masklinn wrote:
>
>>> I know, I know, Ruby people swear by
>>> anonymous code blocks, and I've read Paul Graham too. But I'm really
>>> not so sure that the benefits of anonymous code blocks are great
>>> enough to overcome the disadvantages of anonymous code blocks.
>>>
>> What are the disadvantages of anonymous functions?
>
> In no particular order, and not necessarily exhaustive:
>
> * The risk of obfuscation in your code. That's fairly minimal for
> lambdas, because they're just a single expression, but for a large
> anonymous code block (ACB) defined inside a named function, it may be
> difficult for the reader to easily distinguish which bits are the  
> outer
> function and which are the ACB.
>
I believe that one's unadulterated BS.

> * Loss of useful debugging information. Take this example from Python:
>
>>>> def main(f):
> ...     return f(3)
> ...
>>>> main(lambda n: 2/(n-3))
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "<stdin>", line 2, in main
>  File "<stdin>", line 1, in <lambda>
> ZeroDivisionError: integer division or modulo by zero
>>>>
>>>> def my_special_function(n):
> ...     return 2/(n-3)
> ...
>>>> main(my_special_function)
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "<stdin>", line 2, in main
>  File "<stdin>", line 2, in my_special_function
> ZeroDivisionError: integer division or modulo by zero
>
> If your code has only one anonymous function (whether a lambda or a  
> full
> multi-line block), then it's easy to identify which lambda raised the
> exception: there is only one it could be. But if your code uses lots  
> of
> lambdas, the lack of a function name makes it hard to distinguish one
> <lambda> from another <lambda>. Anonymity makes identification harder.
>
The traceback gives you the line of the anonymous function (even in  
python) so unless you have several anonymous functions on the same  
line, there's no reason why that would be much of an issue.  
Furthermore, Python doesn't provide any more information when the  
error happens out of a function (in a `for` or a `with`), so it's not  
like there's much of a difference here between Ruby's block-based  
approach and Python's statements-based approach.

> * Risk of code-duplication and breaking the principle of Once And Only
> Once. Anonymous functions are generally created, used, then  
> immediately
> thrown away -- or at least made more-or-less inaccessible for reuse.  
> An
> anonymous function stored in a callback still exists, but the coder  
> isn't
> able to easily re-use it for another callback somewhere else in the  
> code.
> Consequently, there's a temptation for the coder to write the same
> function multiple times:
>
> add_button("Parrot", colour=blue, callback=lambda x: x.stuff('a'))
> add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
> add_button("Canary", colour=yellow, callback=lambda x: x.stuff('a'))
>
> instead of:
>
> def bird_callback(x):
>    return x.stuff('a')
>
> add_button("Parrot", colour=blue, callback=bird_callback)
> add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
> add_button("Canary", colour=yellow, callback=bird_callback)
>
Yes, that one I can give you though I don't think that's a big issue.  
And it's not like it's hard to extract the anonymous function into a  
named one and then use that on the third strike, so I really don't  
believe that point holds much water.

> * Recursion is more or less impossible without fragile tricks.
>
> (At least for Python. I don't know how recursion operates in Ruby.)
Code blocks are rarely if ever used recursively. If an operation is  
using anonymous functions recursively, then there's often something  
very wrong with the idea leading to that code. So I find this  
objection irrelevant.


From masklinn at masklinn.net  Fri Jul 31 15:31:21 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 21:31:21 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <200907312048.03922.emmanuel.surleau@gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
	<200907312048.03922.emmanuel.surleau@gmail.com>
Message-ID: <3F279D7F-68C2-4523-B01D-7576F3DFAF3C@masklinn.net>

On 31 Jul 2009, at 20:48 , Emmanuel Surleau wrote:
> On Friday 31 July 2009 19:49:04 Raymond Hettinger wrote:
>> On Jul 20, 9:27 am, Phillip B Oldham <phillip.old... at gmail.com>  
>> wrote:
>>> Specifically the "differences" between lists and tuples have us
>>> confused and have caused many "discussions" in the office. We
>>> understand that lists are mutable and tuples are not, but we're a
>>> little lost as to why the two were kept separate from the start.  
>>> They
>>> both perform a very similar job as far as we can tell.
>>
>> The underlying C code for the two is substantially the same.  In  
>> terms
>> of code, tuples are in effect just immutable lists that have the
>> added
>> feature of being hashable (and therefore usable as dictionary keys or
>> elements of sets).
>>
>> Beyond the mutable/hashable distinction, there is an important
>> philosophical distinction articulated by Guido.  He deems tuples
>> to be useful for struct like groupings of non-homogenous fields
>> and lists to be useful for sequences of homogenous data suitable
>> for looping.
>>
>> While nothing in the list/tuple code requires you to make that
>> distinction,
>> it is important because that philosophy pervades the language.  If  
>> you
>> follow Guido's direction, you'll find that the various parts of the
>> language fit together better.  Do otherwise and you'll be going
>> against
>> the grain.
>
> I might be wrong, but I get the impression that many people don't  
> indeed "get
> it" and use tuples as static arrays and lists when the array needs  
> to be
> dynamically resized. This is certainly how I use them as well.
>
> This would tend to show that Guido's notion here was not particularly
> intuitive.
It's intuitive if you come to Python knowing other languages with  
tuples (which are mostly functional, and in which tuples are *never*  
sequences/iterables). At the end of the day, and if Guido's intention  
truly was what Raymond says, implementing tuples as immutable sequence  
was a mistake. And the documentation is to blame as well: in it,  
tuples are clearly described as a *sequence* type, not a *structure*  
type. 


From jabronson at gmail.com  Fri Jul 31 15:38:01 2009
From: jabronson at gmail.com (Joshua Bronson)
Date: Fri, 31 Jul 2009 12:38:01 -0700 (PDT)
Subject: heapq "key" arguments
References: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>
	<1582f82e-34aa-4b66-b989-c9f8351a5f1c@o9g2000prg.googlegroups.com>
Message-ID: <4f096546-36a1-4633-9a24-1265ce0929ce@q14g2000vbi.googlegroups.com>

On Jul 31, 2:02?pm, Jonathan Gardner <jgard... at jonathangardner.net>
wrote:
> On Jul 31, 10:44?am, Joshua Bronson <jabron... at gmail.com> wrote:
>
> > Say I want to maintain a heap of (x, y) pairs sorted only by
> > first coordinate. Without being able to pass key=itemgetter(0), won't
> > heapifying a list of such pairs unnecessarily compare both
> > coordinates?
>
> It will compare the second value only if the first values are equal.

I don't see how that helps. That's not at all the same thing as being
able to pass key=itemgetter(0).


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 15:45:53 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 16:45:53 -0300
Subject: class or thread id count
References: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>
	<f0446213-638e-41de-b2e8-6c35a1f90004@c2g2000yqi.googlegroups.com>
	<68b09353-7e30-4df2-8e05-32159b03414a@f20g2000prn.googlegroups.com>
Message-ID: <op.uxwszy0ax6zn5v@lepton.softlabbsas.com.ar>

En Thu, 30 Jul 2009 17:09:36 -0300, NighterNet <darkneter at gmail.com>
escribi?:
> On Jul 30, 12:14?pm, r <rt8... at gmail.com> wrote:
>> On Jul 30, 1:13?pm, NighterNet <darkne... at gmail.com> wrote:
>>
>> > Need some help on doing some bit simple id count. It like every time
>> > it create a class orthreadthere is id++. Python 3.1
>>
>> use a class atrribute
>
> class Person():
>   count = 0
>   def __init__(self, name, info):
>       self.name = name
>       self.info = info
>       Person.count+=1
>       self.count = Person.count

Since you menctioned "thread" in the subject, note that the above isn't
thread-safe. You'll need a lock around the last two statements.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 15:46:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 16:46:45 -0300
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
	<7ddvp0F2brmgrU1@mid.uni-berlin.de>
	<33b7685b-054a-442c-8e97-46a5b77f7900@z4g2000prh.googlegroups.com>
Message-ID: <op.uxwr5eyux6zn5v@lepton.softlabbsas.com.ar>

En Thu, 30 Jul 2009 13:31:33 -0300, KB <keith at nekotaku.com> escribi?:
> On Jul 30, 9:23?am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> KB wrote:
>>
>> > From the HTTPCookieProcessor doco, it appears that non-IE browsers
>> > have a cookie file (and example code) but from what I can tell IE uses
>> > a hidden folder. (you can set your location in IE but it appends a
>> > folder "\Temporary Internet Files" ?-
>>
>> > Not sure how to adapt this for IE.

For IE you may use the pywin32 package:

py> import win32inet
py> win32inet.InternetGetCookie("http://sldm/", None)
'__ac_name="softlab"'

Or use ctypes to call the function of the same name in wininet.dll; see
http://msdn.microsoft.com/en-us/library/aa384710(VS.85).aspx

-- 
Gabriel Genellina



From tjreedy at udel.edu  Fri Jul 31 15:55:11 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 15:55:11 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <200907312048.03922.emmanuel.surleau@gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
	<200907312048.03922.emmanuel.surleau@gmail.com>
Message-ID: <h4vi6u$ms8$1@ger.gmane.org>

Emmanuel Surleau wrote:
> 
>> Beyond the mutable/hashable distinction, there is an important 
>> philosophical distinction articulated by Guido.  He deems tuples to
>> be useful for struct like groupings of non-homogenous fields and
>> lists to be useful for sequences of homogenous data suitable for
>> looping.

I think the use of the with 'homegeneous' in this context is wrong
because 1) it is ambiguous or even sometimes not the case, and 2) it
misleads. Everything is an object, so all collections are in that sense
homogeneous. If the meaning is restricted to type(ob), than a list
'mixing' ints and floats would be non-homogeneous and not 'legitimate',
but Guido does not really mean that.

The word tuple comes from relational databases as a generalization of
single, double, triple, quadruple, quintuple, sextuple, sestuple,
octuple, etc. A tuple is a data record with a fixed number of fields
with individual meaning. There is nothing about homogeneity of data type
in that definition. A triple of floats is legitimately a tuple when each
is a coordinate (the individual meanings). In other contexts, the same
triple might properly be a list (such as of heights of people
arbitrarily ordered).

>> While nothing in the list/tuple code requires you to make that 
>> distinction,

which needs to be properly articulated...

>> it is important because that philosophy pervades the language.  If
>> you follow Guido's direction, you'll find that the various parts of
>> the language fit together better.  Do otherwise and you'll be going
>>  against the grain.

Understanding the idea certainly helps understanding the design.
For instance, it explains why no tuple comprehensions.

> I might be wrong, but I get the impression that many people don't
> indeed "get it" and use tuples as static arrays and lists when the
> array needs to be dynamically resized. This is certainly how I use
> them as well.

You also *need* lists if you want to dynamically re-arrange or replace. 
If you *must not* re-arrange or edit, then a tuple will prevent that.

I would also refer back to the idea of tuple as database record.
But a list is needed to edit without copying, so lists can be used for 
writable database records.

I believe tuple(iterable) for indefinite-length iterables is somewhat 
equivalent to tuple(list(iterable)), so there is usually no point to 
constructing a  tuple that way from such an input.

For collections defined by constants, there is a real advantage to using
tuples, since tuple constants are compiled when the bytecode is 
compiled, rather than being dynamically constructed. Inside an inner 
loop, this might make enough time difference that "Practicality beats 
purity" would apply.

> This would tend to show that Guido's notion here was not particularly
>  intuitive.

The problem is that it *is* intuitive, on his part, and usually not well
explained rationally.

Terry Jan Reedy



From python at mrabarnett.plus.com  Fri Jul 31 16:03:53 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 21:03:53 +0100
Subject: base64 Incorrect Padding
In-Reply-To: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
Message-ID: <4A734E29.9080708@mrabarnett.plus.com>

Brandon Fredericks wrote:
> I did a search within this group, but couldn't find any information on
> this.
> 
> I am sending base64 encoded data as the content over http using
> urllib2 urlopen. When I receive the data and attempt to decode it, I
> get an "Incorrect Padding" error. Is there a simple way to fix this? A
> better way to send and receive the data possibly (using base64 of
> course)?

Base-64 encodes 3 bytes (echo in the range 0-255) to 4 bytes (each in a
more restricted range). The length of the output is _always_ a multiple
of 4 (ignoring whitespace); the method adds extra padding bytes (ASCII
'=') to ensure that this is the case if the length of the input isn't a
multiple of 3.

So, if decoding raises an "Incorrect Padding" error then strip out any
whitespace and append extra ASCII '=' to make its length a multiple of
3, then try decoding again. (Or you could just repeatedly add one pad
character and retry, up to 3 times.)


From no.email at please.post  Fri Jul 31 16:10:45 2009
From: no.email at please.post (kj)
Date: Fri, 31 Jul 2009 20:10:45 +0000 (UTC)
Subject: Python docs disappointing
Message-ID: <h4vj45$5hl$1@reader1.panix.com>




I'm pretty new to Python, and I like a lot overall, but I find the
documentation for Python rather poor, overall.

I'm sure that Python experts don't have this problem: they have
internalized some good ways to access the documentation, are
productive with it, and therefore have lost the ability to see why
the Python documentations is deficient for beginners.  This explains
why a suboptimal situation can persist like this: those who are
most able fix it are also the least able to perceive it.

I've heard similar complaints from other experienced programmers
who are trying out Python for the first time: poor documentation.

Here is an *entirely typical* example: on some Unix, try

% pydoc urllib

The displayed documentation mention the optional parameter "data"
in practically every function listed (a few dozen of them).  This
parameter is not documented *anywhere* on that page.  All that we
are told is that its default value is always None.

I'm sure that I can find a full description of this parameter if
I fire up Google, and search online.  In fact, more likely than
not, I'll find far more documentation than I want.  But my point
is that a programmer should not need to do this.  The full
documentation should be readily accessible directly through a few
keystrokes.

I would love to know how experienced Python programmers quickly
zero in on the Python documentation they need.

TIA!

kynn


From jstroud at mbi.ucla.edu  Fri Jul 31 16:11:49 2009
From: jstroud at mbi.ucla.edu (James Stroud)
Date: Fri, 31 Jul 2009 13:11:49 -0700
Subject: Python quirk in evaluation order
Message-ID: <h4vj65$40k$1@zinnia.noc.ucla.edu>

Python 2.5:

mbi136-176 211% python
*** Pasting of code with ">>>" or "..." has been enabled.
########################################################################
  ##                             ipython                              ##
########################################################################
py> b = 4 if True else b
py> b
4


Isn't the right side supposed to be evaluated first?


From emmanuel.surleau at gmail.com  Fri Jul 31 16:26:58 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 22:26:58 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <h4vi6u$ms8$1@ger.gmane.org>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<200907312048.03922.emmanuel.surleau@gmail.com>
	<h4vi6u$ms8$1@ger.gmane.org>
Message-ID: <200907312226.59027.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 21:55:11 Terry Reedy wrote:
> Emmanuel Surleau wrote:
> >> Beyond the mutable/hashable distinction, there is an important
> >> philosophical distinction articulated by Guido.  He deems tuples to
> >> be useful for struct like groupings of non-homogenous fields and
> >> lists to be useful for sequences of homogenous data suitable for
> >> looping.
>
> I think the use of the with 'homegeneous' in this context is wrong
> because 1) it is ambiguous or even sometimes not the case, and 2) it
> misleads. Everything is an object, so all collections are in that sense
> homogeneous. If the meaning is restricted to type(ob), than a list
> 'mixing' ints and floats would be non-homogeneous and not 'legitimate',
> but Guido does not really mean that.
>
> The word tuple comes from relational databases as a generalization of
> single, double, triple, quadruple, quintuple, sextuple, sestuple,
> octuple, etc. A tuple is a data record with a fixed number of fields
> with individual meaning. There is nothing about homogeneity of data type
> in that definition. A triple of floats is legitimately a tuple when each
> is a coordinate (the individual meanings). In other contexts, the same
> triple might properly be a list (such as of heights of people
> arbitrarily ordered).

My understanding is that, in this context, it's not so much data types which 
are heterogeneous, but the semantic meaning of the data. For instance, a tuple 
containing (first_name, last_name, address) would be a "legitimate" tuple, but 
not a tuple containing (address, address, address), which, if we follow 
Guido's philosophy, ought to be represented as a list.

Whether including the distinction in the language offers any practical benefit 
is questionable.

[snip]

> > This would tend to show that Guido's notion here was not particularly
> >  intuitive.
>
> The problem is that it *is* intuitive, on his part, and usually not well
> explained rationally.

Excellent point.

Cheers,

Emm


From robert.kern at gmail.com  Fri Jul 31 16:28:01 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 31 Jul 2009 15:28:01 -0500
Subject: Python docs disappointing
In-Reply-To: <h4vj45$5hl$1@reader1.panix.com>
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <h4vk4h$ruk$1@ger.gmane.org>

On 2009-07-31 15:10, kj wrote:

> I would love to know how experienced Python programmers quickly
> zero in on the Python documentation they need.

http://docs.python.org/library/urllib

I use Firefox's "Quick Searches" feature to make getting this URL as fast as 
possible:

   "m urllib"

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From rt8396 at gmail.com  Fri Jul 31 16:29:36 2009
From: rt8396 at gmail.com (r)
Date: Fri, 31 Jul 2009 13:29:36 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>

On Jul 31, 3:10?pm, kj <no.em... at please.post> wrote:
> I'm pretty new to Python, and I like a lot overall, but I find the
> documentation for Python rather poor, overall.
[snip]

If you mean the built-in docs i *highly agree* with you. if you mean
docs/tutorials available across the WWW i *highly disagree* with you,
and if you mean the command line "help" i also *highly disagree*, of
which python has the-best-in the-world!

I am using 2.6.2 and the help docs are a joke. trying to find even the
simplest thing (built-in functions, etc...) is like pulling teeth. I
do not look at them anymore, or do i plan to in the future. Luckily i
know python pretty well, but i can't image the horrors a new Python
Programmer must face now...

Kj, you could not be more right. Doc maintainers need to get some
feedback from Python noobies when writing this stuff. Does anybody
remember CP4E? I know Guido put a lot of effort into this project and
very much believed in this philosophy(circa 1999~2005), although it
never really went very far, i still believe in Guido's heart the CP4E
exists -- if only barley clinging to life(...maybe?)

any thoughts on this Pythonistas?


From robert.kern at gmail.com  Fri Jul 31 16:31:21 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 31 Jul 2009 15:31:21 -0500
Subject: Python quirk in evaluation order
In-Reply-To: <h4vj65$40k$1@zinnia.noc.ucla.edu>
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <h4vkaq$t30$1@ger.gmane.org>

On 2009-07-31 15:11, James Stroud wrote:
> Python 2.5:
>
> mbi136-176 211% python
> *** Pasting of code with ">>>" or "..." has been enabled.
> ########################################################################
> ## ipython ##
> ########################################################################
> py> b = 4 if True else b
> py> b
> 4
>
>
> Isn't the right side supposed to be evaluated first?

The right side of the assignment or the if-else expression? The "expr1 if 
condition else expr2" expression evaluates condition, then either expr1 or expr2 
depending on the result. The other expression is unevaluated.

 >>> a
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
NameError: name 'a' is not defined
 >>> b
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
NameError: name 'b' is not defined
 >>> 5 if True else b
5
 >>> a if False else 5
5

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From marduk at letterboxes.org  Fri Jul 31 16:33:00 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Fri, 31 Jul 2009 16:33:00 -0400
Subject: Python quirk in evaluation order
In-Reply-To: <h4vj65$40k$1@zinnia.noc.ucla.edu>
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <1249072381.24514.4.camel@centar>

On Fri, 2009-07-31 at 13:11 -0700, James Stroud wrote:
> Python 2.5:
> 
> mbi136-176 211% python
> *** Pasting of code with ">>>" or "..." has been enabled.
> ########################################################################
>   ##                             ipython                              ##
> ########################################################################
> py> b = 4 if True else b
> py> b
> 4
> 
> 
> Isn't the right side supposed to be evaluated first?

Yes, the right hand side of the '=', which is evaluated from LtoR.

>From the Language Reference:

        Python evaluates expressions from left to right. Notice that
        while evaluating an assignment, the right-hand side is evaluated
        before the left-hand side.

So the right-hand side of the '=' is evaluated first:

    4 if True else b

And that's evaluated from left to right:

   4

Therefore:

b = 4





From emmanuel.surleau at gmail.com  Fri Jul 31 16:34:06 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 22:34:06 +0200
Subject: Python docs disappointing
In-Reply-To: <h4vj45$5hl$1@reader1.panix.com>
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <200907312234.06374.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 22:10:45 kj wrote:
> I'm pretty new to Python, and I like a lot overall, but I find the
> documentation for Python rather poor, overall.
>
> I'm sure that Python experts don't have this problem: they have
> internalized some good ways to access the documentation, are
> productive with it, and therefore have lost the ability to see why
> the Python documentations is deficient for beginners.  This explains
> why a suboptimal situation can persist like this: those who are
> most able fix it are also the least able to perceive it.
>
> I've heard similar complaints from other experienced programmers
> who are trying out Python for the first time: poor documentation.

The documentation on python.org is quite extensive. In particular, you may 
want to look at the PEPs, which offer fascinating insights for the reasoning 
behind particular features of Python.

> Here is an *entirely typical* example: on some Unix, try
>
> % pydoc urllib
>
> The displayed documentation mention the optional parameter "data"
> in practically every function listed (a few dozen of them).  This
> parameter is not documented *anywhere* on that page.  All that we
> are told is that its default value is always None.
>
> I'm sure that I can find a full description of this parameter if
> I fire up Google, and search online.  In fact, more likely than
> not, I'll find far more documentation than I want.  But my point
> is that a programmer should not need to do this.  The full
> documentation should be readily accessible directly through a few
> keystrokes.

You have first-grade documentation on the Python website: 
http://docs.python.org/library/urllib.html
I'm not really using pydoc, but I'd wager it's more used as a quick lookup 
than anything else.

> I would love to know how experienced Python programmers quickly
> zero in on the Python documentation they need.

I wouldn't count myself as an 'experienced' Python programmer, but I rely on 
docs.python.org for most things with regards to the standard library.

Cheers,

Emm


From __peter__ at web.de  Fri Jul 31 16:39:25 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 22:39:25 +0200
Subject: Python quirk in evaluation order
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <h4vkpr$3r5$01$1@news.t-online.com>

James Stroud wrote:

> py> b = 4 if True else b
> py> b
> 4

> Isn't the right side supposed to be evaluated first?

Perhaps it becomes clearer if you change it a bit:


>>> b = 4 if True else whatever
>>> whatever
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'whatever' is not defined

I. e. the else clause is never evaluated at all.

Peter



From breamoreboy at yahoo.co.uk  Fri Jul 31 16:55:35 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 31 Jul 2009 21:55:35 +0100
Subject: Python docs disappointing
In-Reply-To: <a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>
Message-ID: <h4vlnq$sh$1@ger.gmane.org>

r wrote:
> On Jul 31, 3:10 pm, kj <no.em... at please.post> wrote:
>> I'm pretty new to Python, and I like a lot overall, but I find the
>> documentation for Python rather poor, overall.
> [snip]
> 
> If you mean the built-in docs i *highly agree* with you. if you mean
> docs/tutorials available across the WWW i *highly disagree* with you,
> and if you mean the command line "help" i also *highly disagree*, of
> which python has the-best-in the-world!
> 
> I am using 2.6.2 and the help docs are a joke. trying to find even the
> simplest thing (built-in functions, etc...) is like pulling teeth. I
> do not look at them anymore, or do i plan to in the future. Luckily i
> know python pretty well, but i can't image the horrors a new Python
> Programmer must face now...
> 
> Kj, you could not be more right. Doc maintainers need to get some
> feedback from Python noobies when writing this stuff. Does anybody
> remember CP4E? I know Guido put a lot of effort into this project and
> very much believed in this philosophy(circa 1999~2005), although it
> never really went very far, i still believe in Guido's heart the CP4E
> exists -- if only barley clinging to life(...maybe?)
> 
> any thoughts on this Pythonistas?

I entirely agree with these comments.  Looking at home on the compiled 
help file on windows for python 2.6.2 I can't see anything except for 
some icons at the top, the Contents, Index, Search and Favorites tabs on 
the left and the following on the right.

What's new in Python 2.6? or all "What's new" documents since 2.0
Tutorial start here
Using Python how to use Python on different platforms
Language Reference describes syntax and language elements
Library Reference keep this under your pillow
Python HOWTOs in-depth documents on specific topics
Extending and Embedding tutorial for C/C++ programmers
Python/C API reference for C/C++ programmers
Installing Python Modules information for installers & sys-admins
Distributing Python Modules sharing modules with others
Documenting Python guide for documentation authors
Indices and tables:
Global Module Index quick access to all modules
General Index all functions, classes, terms
Glossary the most important terms explained
Search page search this documentation
Complete Table of Contents lists all sections and subsections
Meta information:
Reporting bugs
About the documentation  History and License of Python
Copyright

Apart from that what have the Pythonistas ever done for us? Nothing!:)

-- 
Kindest regards.

Mark Lawrence.



From nagle at animats.com  Fri Jul 31 16:56:25 2009
From: nagle at animats.com (John Nagle)
Date: Fri, 31 Jul 2009 13:56:25 -0700
Subject: beautiful soup
In-Reply-To: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
References: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
Message-ID: <4a7359ce$0$1629$742ec2ed@news.sonic.net>

xubin.cz wrote:
> hi, everyone
> 
> Is there any pakage or module handling html document like beautiful
> soup?

    Try "http://code.google.com/p/html5lib/".

That's supposed to be a parser which complies with the HTML 5 specification,
including its rules for handling bad HTML.

					John Nagle


From maxerickson at gmail.com  Fri Jul 31 17:04:10 2009
From: maxerickson at gmail.com (Max Erickson)
Date: Fri, 31 Jul 2009 21:04:10 +0000 (UTC)
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
	<4A734E29.9080708@mrabarnett.plus.com>
Message-ID: <Xns9C59AD9F315DDmaxericksongmailcom@80.91.229.13>

MRAB <python at mrabarnett.plus.com> wrote:

> Brandon Fredericks wrote:
>> I did a search within this group, but couldn't find any
>> information on this.
>> 
>> I am sending base64 encoded data as the content over http using
>> urllib2 urlopen. When I receive the data and attempt to decode
>> it, I get an "Incorrect Padding" error. Is there a simple way to
>> fix this? A better way to send and receive the data possibly
>> (using base64 of course)?
> 
> Base-64 encodes 3 bytes (echo in the range 0-255) to 4 bytes
> (each in a more restricted range). The length of the output is
> _always_ a multiple of 4 (ignoring whitespace); the method adds
> extra padding bytes (ASCII '=') to ensure that this is the case
> if the length of the input isn't a multiple of 3.
> 
> So, if decoding raises an "Incorrect Padding" error then strip
> out any whitespace and append extra ASCII '=' to make its length
> a multiple of 3, then try decoding again. (Or you could just
> repeatedly add one pad character and retry, up to 3 times.)

The length of the encoded string should be a multiple of 4 (as you 
state in the second sentence of your post), not a multiple of 3.


max



From davea at ieee.org  Fri Jul 31 17:07:01 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 31 Jul 2009 17:07:01 -0400
Subject: Python quirk in evaluation order
In-Reply-To: <h4vj65$40k$1@zinnia.noc.ucla.edu>
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <4A735CF5.1070304@ieee.org>

James Stroud wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Python 2.5:
>
> mbi136-176 211% python
> *** Pasting of code with ">>>" or "..." has been enabled.
> ########################################################################
>  ##                             ipython                              ##
> ########################################################################
> py> b = 4 if True else b
> py> b
> 4
>
>
> Isn't the right side supposed to be evaluated first?
>

I don't have a clue what value you expected b to have.  The if/else 
ternary expression is roughly equivalent to:
              if True:
                    b = 4
              else
                    b = b
The first part to be evaluated is the if expression, which is hard-coded 
to True.  Then the part to the left will be used for the expression 
result, and the part on the right ignored.  This is because of 
short-circuit rules.

Try this one for size:
b = 22 if True else  I.am.Not.Being.Evaluated(4.4)

The else clause does need to be a syntactically valid expression, but 
it's not evaluated unless the if-expression is false.

DaveA




From pavlovevidence at gmail.com  Fri Jul 31 17:16:48 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 14:16:48 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>

On Jul 31, 1:10?pm, kj <no.em... at please.post> wrote:
> I'm pretty new to Python, and I like a lot overall, but I find the
> documentation for Python rather poor, overall.
>
> I'm sure that Python experts don't have this problem: they have
> internalized some good ways to access the documentation, are
> productive with it, and therefore have lost the ability to see why
> the Python documentations is deficient for beginners.

That may be so, but I do remember when I was a beginner myself and I
had no issue with the documentation.


[snip]
> I'm sure that I can find a full description of this parameter if
> I fire up Google, and search online.

Are you aware that Python ships with a full set of documentation,
where (for instance) the meaning of "data" in urllib is defined?  You
don't need Google.


> In fact, more likely than
> not, I'll find far more documentation than I want. ?But my point
> is that a programmer should not need to do this. ?The full
> documentation should be readily accessible directly through a few
> keystrokes.

Well, no one volunteered to do that.  Oh well.


> I would love to know how experienced Python programmers quickly
> zero in on the Python documentation they need.

Choose bookmark in web browser for Python documentation -> keyword
search for correct module (easy with firefox) -> scroll.

This might not be the smoothest method ever (omg you have to use a
*mouse*) but it should be usable enough.


Carl Banks


From python at mrabarnett.plus.com  Fri Jul 31 17:17:30 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 22:17:30 +0100
Subject: base64 Incorrect Padding
In-Reply-To: <Xns9C59AD9F315DDmaxericksongmailcom@80.91.229.13>
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>	<4A734E29.9080708@mrabarnett.plus.com>
	<Xns9C59AD9F315DDmaxericksongmailcom@80.91.229.13>
Message-ID: <4A735F6A.1010405@mrabarnett.plus.com>

Max Erickson wrote:
> MRAB <python at mrabarnett.plus.com> wrote:
> 
>> Brandon Fredericks wrote:
>>> I did a search within this group, but couldn't find any
>>> information on this.
>>>
>>> I am sending base64 encoded data as the content over http using
>>> urllib2 urlopen. When I receive the data and attempt to decode
>>> it, I get an "Incorrect Padding" error. Is there a simple way to
>>> fix this? A better way to send and receive the data possibly
>>> (using base64 of course)?
>> Base-64 encodes 3 bytes (echo in the range 0-255) to 4 bytes
>> (each in a more restricted range). The length of the output is
>> _always_ a multiple of 4 (ignoring whitespace); the method adds
>> extra padding bytes (ASCII '=') to ensure that this is the case
>> if the length of the input isn't a multiple of 3.
>>
>> So, if decoding raises an "Incorrect Padding" error then strip
>> out any whitespace and append extra ASCII '=' to make its length
>> a multiple of 3, then try decoding again. (Or you could just
>> repeatedly add one pad character and retry, up to 3 times.)
> 
> The length of the encoded string should be a multiple of 4 (as you 
> state in the second sentence of your post), not a multiple of 3.
> 
Oops, correct! :-)


From masklinn at masklinn.net  Fri Jul 31 17:19:07 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 23:19:07 +0200
Subject: Python docs disappointing
In-Reply-To: <200907312234.06374.emmanuel.surleau@gmail.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<200907312234.06374.emmanuel.surleau@gmail.com>
Message-ID: <E8ADB0D7-6DD2-4378-A74E-05A9383137A0@masklinn.net>

On 31 Jul 2009, at 22:34 , Emmanuel Surleau wrote:
> You have first-grade documentation on the Python website:
> http://docs.python.org/library/urllib.html
> I'm not really using pydoc, but I'd wager it's more used as a quick  
> lookup
> than anything else.
Another important documentary resource for the stdlib is Doug  
Hellmann's awesome Python Module of the Day series (http://www.doughellmann.com/PyMOTW/ 
)


From pavlovevidence at gmail.com  Fri Jul 31 17:23:02 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 14:23:02 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>
	<mailman.4073.1249073738.8015.python-list@python.org>
Message-ID: <7bb4df03-f09a-40b0-83f8-1c6d0c9800a8@j21g2000vbn.googlegroups.com>

On Jul 31, 1:55?pm, Mark Lawrence <breamore... at yahoo.co.uk> wrote:
> Apart from that what have the Pythonistas ever done for us? Nothing!:)


Please don't feed the trolls.

And if you do feed the trolls don't smile at them.


Carl Banks


From no.email at please.post  Fri Jul 31 17:28:36 2009
From: no.email at please.post (kj)
Date: Fri, 31 Jul 2009 21:28:36 +0000 (UTC)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
Message-ID: <h4vnm4$jvi$1@reader1.panix.com>

In <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4 at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevidence at gmail.com> writes:

>(omg you have to use a
>*mouse*)

That's precisely the point.  There's a huge number of programmers
out there who, like me, *hate* to use the mouse while they're
coding.  It is truly disappointing to us that the developers of
Python chose to completely disregard this constituency.

This is one area in which Perl still whips Python...

kynn 


From rt8396 at gmail.com  Fri Jul 31 17:30:47 2009
From: rt8396 at gmail.com (r)
Date: Fri, 31 Jul 2009 14:30:47 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
Message-ID: <4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>

On Jul 31, 4:16?pm, Carl Banks <pavlovevide... at gmail.com> wrote:
> On Jul 31, 1:10?pm, kj <no.em... at please.post> wrote:
>
> > I'm pretty new to Python, and I like a lot overall, but I find the
> > documentation for Python rather poor, overall.
>
> > I'm sure that Python experts don't have this problem: they have
> > internalized some good ways to access the documentation, are
> > productive with it, and therefore have lost the ability to see why
> > the Python documentations is deficient for beginners.
>
> That may be so, but I do remember when I was a beginner myself and I
> had no issue with the documentation.

have you tried the new docs (>= 2.6) The interface has changed
drastically as to render itself completely useless. The old docs (<=
2.5) --the ones i learned from-- where flawless.


@ Mark Lawrence
Have you clicked any of those links? try the "Tutorial start here" and
then try to find a menu of sorts. It seems you have to click "next" to
navigate. Thats pretty counter intuitive if you need to get to page
589!! Upon clicking the tutorial link in the OLD DOCS, you where
presented with a nice menu for concise navigation.


From python at rcn.com  Fri Jul 31 17:43:17 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 14:43:17 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com> 
	<mailman.4061.1249066087.8015.python-list@python.org>
Message-ID: <4677d753-364f-4d29-9091-e55008daec83@12g2000pri.googlegroups.com>

> > While nothing in the list/tuple code requires you to make that
> > distinction,
> > it is important because that philosophy pervades the language. ?If you
> > follow Guido's direction, you'll find that the various parts of the
> > language fit together better. ?Do otherwise and you'll be going
> > against
> > the grain.
>
> I might be wrong, but I get the impression that many people don't indeed "get
> it" and use tuples as static arrays and lists when the array needs to be
> dynamically resized. This is certainly how I use them as well.
>
> This would tend to show that Guido's notion here was not particularly
> intuitive.

No, it just shows that they are not Dutch ;-)

IIRC, Aahz once made an eloquent statement about how languages aren't
intuitive because different people have different intuitions.  The
fact
is that every language has its own set of ways.  People usually pick-
up
on what is Pythonic in a short order.  The problem comes when people
decide-in-advance how the language ought to be -- it takes them longer
to pick-up the culture and idioms.  More than one person here has
observed that the time to learn to program Pythonically is inversely
proportional to their experience in Java.

It is perfectly okay for you to use tuples for statically sized
arrays.
That isn't wrong.  It is against then grain though.  Guido articulated
his concept early and many of his minions (me included) have designed
the APIs and optimizations to flow nicely with his preferred way of
doing things.


Raymond


From breamoreboy at yahoo.co.uk  Fri Jul 31 17:53:02 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 31 Jul 2009 22:53:02 +0100
Subject: Python docs disappointing
In-Reply-To: <4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>
Message-ID: <h4vp3d$9kr$1@ger.gmane.org>

r wrote:
> On Jul 31, 4:16 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
>> On Jul 31, 1:10 pm, kj <no.em... at please.post> wrote:
>>
>>> I'm pretty new to Python, and I like a lot overall, but I find the
>>> documentation for Python rather poor, overall.
>>> I'm sure that Python experts don't have this problem: they have
>>> internalized some good ways to access the documentation, are
>>> productive with it, and therefore have lost the ability to see why
>>> the Python documentations is deficient for beginners.
>> That may be so, but I do remember when I was a beginner myself and I
>> had no issue with the documentation.
> 
> have you tried the new docs (>= 2.6) The interface has changed
> drastically as to render itself completely useless. The old docs (<=
> 2.5) --the ones i learned from-- where flawless.
> 
> 
> @ Mark Lawrence
> Have you clicked any of those links? try the "Tutorial start here" and
> then try to find a menu of sorts. It seems you have to click "next" to
> navigate. Thats pretty counter intuitive if you need to get to page
> 589!! Upon clicking the tutorial link in the OLD DOCS, you where
> presented with a nice menu for concise navigation.

Yes.  Works perfectly as evidenced by the fact that this evening I've 
checked data on the cProfile, pstats and array modules.

-- 
Kindest regards.

Mark Lawrence.



From python at rcn.com  Fri Jul 31 17:55:16 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 14:55:16 -0700 (PDT)
Subject: Help understanding the decisions *behind* python? - immutable 
	objects
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com> 
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
Message-ID: <6b343b95-27d0-4167-bef2-d3e0a5fd87dc@u38g2000pro.googlegroups.com>

On Jul 26, 11:24?am, John Nagle <na... at animats.com> wrote:
> A tuple is really a frozen list. ?Arguably, frozen objects
> should have been a general concept. ?Conceptually, they're
> simple - once "__init__" has run, there can be no more changes
> to fields of the object.

I would argue that freezing and thawing (making the container
statefull)
is the proverbial road to hell paved with good intentions.  It is
roughly in the same category as dynamic scoping -- programs become
harder to analyze for correctness -- code that used to work can
break because something froze it along the way (perhaps to use it
as a key for dict or set in a caching function) or because something
unfroze it (so it could mutate a value).


Raymond



From brfredericks at gmail.com  Fri Jul 31 17:58:43 2009
From: brfredericks at gmail.com (bfrederi)
Date: Fri, 31 Jul 2009 14:58:43 -0700 (PDT)
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
	<mailman.4067.1249070631.8015.python-list@python.org>
Message-ID: <b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>

So what if I used a different encoding that isn't ASCII? Like UTF-8?
Would that give me lengths that are multiples of 4 based on how the
characters are represented? Or would I still need to pad with '='?


From pavlovevidence at gmail.com  Fri Jul 31 18:03:25 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 15:03:25 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
Message-ID: <09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>

On Jul 31, 2:28?pm, kj <no.em... at please.post> wrote:
> In <e22013d0-fbad-44e0-919b-ad5bb5f2d... at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevide... at gmail.com> writes:
>
> >(omg you have to use a
> >*mouse*)
>
> That's precisely the point. ?There's a huge number of programmers
> out there who, like me, *hate* to use the mouse while they're
> coding.

You would have figured one of them would have written a script or
something if there were so many.  Maybe check the Python Cookbook for
someone's pet trick, I bet there is one or two there.  Or figure out a
way to use elinks, the text mode web browser.  You know, text mode
browsers have come a long way since the lynx days.


>?It is truly disappointing to us that the developers of
> Python chose to completely disregard this constituency.

Python is a volunteer effort, chief.

If all these programmers have this itch, as you claim, they've all
disregarded themselves by failing to contribute something.


> This is one area in which Perl still whips Python...

No way.  Perl's man pages are organized so poorly there is no
ergonomic pit deep enough to offset them.  Quick, what man page is the
"do" statement documented in?


Carl Banks


From no.email at please.post  Fri Jul 31 18:09:42 2009
From: no.email at please.post (kj)
Date: Fri, 31 Jul 2009 22:09:42 +0000 (UTC)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
Message-ID: <h4vq36$4ik$1@reader1.panix.com>

In <09bf4f17-40a5-4bad-81d3-1950545b7570 at g6g2000vbr.googlegroups.com>
Carl Banks <pavlovevidence at gmail.com> writes:

<snip>

Thanks.  Your remarks at least confirm that my impression was not
simply due to my noob ignorance: the keyboard-accessible docs are
indeed as poor as they look.

kynn


From pfeldman at verizon.net  Fri Jul 31 18:17:56 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 31 Jul 2009 15:17:56 -0700 (PDT)
Subject: possible to round number and convert to string?
Message-ID: <24763821.post@talk.nabble.com>


I'd like to be able to convert a float to a string representation in which
the number is rounded to a specified number of digits.  If num2str is a
hypothetical function that does this, then num2str(pi,3) would be '3.142'
(not '3.141').  I've been told that there is no such function in Python.  I
tried to write this myself, but wasn't successful.  Any suggestions will be
appreciated.
-- 
View this message in context: http://www.nabble.com/possible-to-round-number-and-convert-to-string--tp24763821p24763821.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From python at mrabarnett.plus.com  Fri Jul 31 18:24:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 23:24:09 +0100
Subject: base64 Incorrect Padding
In-Reply-To: <b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>	<mailman.4067.1249070631.8015.python-list@python.org>
	<b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>
Message-ID: <4A736F09.6090505@mrabarnett.plus.com>

bfrederi wrote:
> So what if I used a different encoding that isn't ASCII? Like UTF-8?
> Would that give me lengths that are multiples of 4 based on how the
> characters are represented? Or would I still need to pad with '='?

I think that when it says Base-64 it's talking about the byte values
used for the encoding.


From david.birdsong at gmail.com  Fri Jul 31 18:27:19 2009
From: david.birdsong at gmail.com (birdsong)
Date: Fri, 31 Jul 2009 15:27:19 -0700 (PDT)
Subject: Non-blocking read with popen subprocess
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
	<824f8092-55b1-4df2-a6b5-74a4b1b1d9ea@i18g2000pro.googlegroups.com>
Message-ID: <fa7a8d57-57eb-4ec3-984d-b10cd5c10348@i18g2000pro.googlegroups.com>

On Jul 30, 7:30?pm, Jonathan Gardner <jgard... at jonathangardner.net>
wrote:
> On Jul 30, 5:24?pm, Dhanesh <dhanesh... at gmail.com> wrote:
>
>
>
> > how can I we have a non blocking read ?
>
> Seehttp://docs.python.org/library/popen2.html#flow-control-issues
>
> Note well: In the non-blocking world, you have to use select() or poll
> () to get your job done.

I solved a problem just yesterday regarding select on a Popen.stdout
file descriptor that was created with a 100Mb buffer.  I'd love it if
anybody could critique my solution and my understanding of my
findings.

In my case, select would return with my Popen object ready for read,
I'd go off and try to read and then my read would block.  After a few
strace's I found that Popen.stdout.read(), which I am assuming is the
same as the read builtin, would make multiple read system calls, in
many cases blocking until it returned my default buffer size.

Sure enough, it's in the docs: http://docs.python.org/library/stdtypes.html?highlight=fread
"""
Note that this method may call the underlying C function fread() more
than once in an effort to acquire as close to size bytes as possible.
Also note that when in non-blocking mode, less data than was requested
may be returned, even if no size parameter was given.
"""

I couldn't find a way to tell subprocess to return my stdout fd in non-
blocking mode, but then I thought about it not being a problem with
the fd and how it was opened as much as a problem with the read
call.

  A non-blocking fd will have a read call throw EWOULDBLOCK when asked
for more bytes than is in buffer, a blocking fd would have read just
return fewer bytes  ...do I have this this right?

I can handle assembling the data fine, I just don't want to block.

I wrote a little test program to spit out random stdout to test a
Popen object's stdout in os.read.  The len() of the result of os.read
was all over the place depending on how quickly i re-ran read() on the
fd.  There were slight delays from time to time, but I attributed that
to the interpreter being context switched in, ssh delays ...or the
weather...in general the return was pretty fast.

I switched my program to use os.read and now it's snappy and spends
most of it's time blocking on select exactly where I want it to.

(this is on linux btw, I guess os.read is different everywhere)

> You may want to look at "communicate" (http://docs.python.org/library/subprocess.html#popen-objects) which may be what you need.



From Nikolaus at rath.org  Fri Jul 31 18:38:25 2009
From: Nikolaus at rath.org (Nikolaus Rath)
Date: Fri, 31 Jul 2009 18:38:25 -0400
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
Message-ID: <87prbgscke.fsf@vostro.rath.org>

Carl Banks <pavlovevidence at gmail.com> writes:
>> This is one area in which Perl still whips Python...
>
> No way.  Perl's man pages are organized so poorly there is no
> ergonomic pit deep enough to offset them.  Quick, what man page is the
> "do" statement documented in?

Of course there is:

$ perldoc -f do | head
       do BLOCK
               Not really a function.  Returns the value of the last command
               in the sequence of commands indicated by BLOCK.  When modified
               by the "while" or "until" loop modifier, executes the BLOCK
               once before testing the loop condition. (On other statements
               the loop modifiers test the conditional first.)

               "do BLOCK" does not count as a loop, so the loop control
               statements "next", "last", or "redo" cannot be used to leave or
               restart the block.  See perlsyn for alternative strategies.
$ 


Best,

   -Nikolaus

-- 
 ?Time flies like an arrow, fruit flies like a Banana.?

  PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6  02CF A9AD B7F8 AE4E 425C


From malaclypse2 at gmail.com  Fri Jul 31 18:42:03 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Fri, 31 Jul 2009 18:42:03 -0400
Subject: possible to round number and convert to string?
In-Reply-To: <24763821.post@talk.nabble.com>
References: <24763821.post@talk.nabble.com>
Message-ID: <16651e80907311542w1a94168egd173641cdfb002ce@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:17 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> I'd like to be able to convert a float to a string representation in which
> the number is rounded to a specified number of digits. ?If num2str is a
> hypothetical function that does this, then num2str(pi,3) would be '3.142'
> (not '3.141'). ?I've been told that there is no such function in Python. ?I
> tried to write this myself, but wasn't successful. ?Any suggestions will be
> appreciated.

You should be able to do this with standard string formatting.  (
http://docs.python.org/library/stdtypes.html#string-formatting )

For example:
>>> from math import pi
>>> pi
3.1415926535897931
>>> "%0.3f" % pi
'3.142'

If you need it as a function, you could do something like this:
>>> def num2str(num, precision):
	return "%0.*f" % (precision, num)

>>> num2str(pi, 4)
'3.1416'

Does that do what you need?

-- 
Jerry


From user at example.net  Fri Jul 31 18:42:21 2009
From: user at example.net (superpollo)
Date: Sat, 01 Aug 2009 00:42:21 +0200
Subject: possible to round number and convert to string?
In-Reply-To: <mailman.4079.1249078685.8015.python-list@python.org>
References: <mailman.4079.1249078685.8015.python-list@python.org>
Message-ID: <4a737350$0$28514$4fafbaef@reader2.news.tin.it>

Dr. Phillip M. Feldman wrote:
> I'd like to be able to convert a float to a string representation in which
> the number is rounded to a specified number of digits.  If num2str is a
> hypothetical function that does this, then num2str(pi,3) would be '3.142'
> (not '3.141').  I've been told that there is no such function in Python.  I
> tried to write this myself, but wasn't successful.  Any suggestions will be
> appreciated.

 >>> import math
 >>> s = str(round(math.pi, 3))
 >>> s
'3.142'
 >>>


From gallium.arsenide at gmail.com  Fri Jul 31 18:46:22 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Fri, 31 Jul 2009 15:46:22 -0700 (PDT)
Subject: possible to round number and convert to string?
References: <mailman.4079.1249078685.8015.python-list@python.org>
Message-ID: <3b719e5e-0cce-4059-86e1-623a0ad7777a@f33g2000vbm.googlegroups.com>

On Jul 31, 6:17?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> I'd like to be able to convert a float to a
> string representation in which the number is
> rounded to a specified number of digits. ?If
> num2str is a hypothetical function that does
> this, then num2str(pi,3) would be '3.142'
> (not '3.141'). ?I've been told that there is
> no such function in Python. ?I tried to write
> this myself, but wasn't successful. ?Any
> suggestions will be appreciated.

This is what I get in Python 2.6.1 on Windows:

>>> from math import pi
>>> pi
3.1415926535897931
>>> round(pi, 3)
3.1419999999999999
>>> str(round(pi, 3))
'3.142'

John


From cjns1989 at gmail.com  Fri Jul 31 18:54:52 2009
From: cjns1989 at gmail.com (Chris Jones)
Date: Fri, 31 Jul 2009 18:54:52 -0400
Subject: Python docs disappointing
In-Reply-To: <09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
Message-ID: <20090731225452.GK25977@turki.gavron.org>

On Fri, Jul 31, 2009 at 06:03:25PM EDT, Carl Banks wrote:
> On Jul 31, 2:28?pm, kj <no.em... at please.post> wrote:
> > In <e22013d0-fbad-44e0-919b-ad5bb5f2d... at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevide... at gmail.com> writes:
> >
> > >(omg you have to use a
> > >*mouse*)
> >
> > That's precisely the point. ?There's a huge number of programmers
> > out there who, like me, *hate* to use the mouse while they're
> > coding.
> 
> You would have figured one of them would have written a script or
> something if there were so many.  Maybe check the Python Cookbook for
> someone's pet trick, I bet there is one or two there.  Or figure out a
> way to use elinks, the text mode web browser.  You know, text mode
> browsers have come a long way since the lynx days.

So true.. I would add that one of the unplanned merits of a well-thought
out text mode browser such as ELinks is to remove all the fluff and
leave you, the reader, face to face with the site's content - or lack
thereof.

CJ


From pavlovevidence at gmail.com  Fri Jul 31 18:55:19 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 15:55:19 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
	<h4vq36$4ik$1@reader1.panix.com>
Message-ID: <109f1ff7-8fa9-40d3-80b4-1e90b5fc669c@d34g2000vbm.googlegroups.com>

On Jul 31, 3:09?pm, kj <no.em... at please.post> wrote:
> In <09bf4f17-40a5-4bad-81d3-1950545b7... at g6g2000vbr.googlegroups.com>
>
> Carl Banks <pavlovevide... at gmail.com> writes:
>
> <snip>
>
> Thanks. ?Your remarks at least confirm that my impression was not
> simply due to my noob ignorance: the keyboard-accessible docs are
> indeed as poor as they look.


In the standard library, docstrings (which is what pydoc prints) are
intended to be a brief explanation/reminder of usage, not an
exhaustive description.  Where docstrings are present, they are more
or less adequate for their intended use (although the quality of
docstrings does vary highly throughout the library).

If you are trying to use pydoc in a way not intended, then yes you
would likely find that they are poor when used in that unintended way.

Docstrings take up memory in a running process, so they are not ever
likely to be converted to an exhaustive description.  Your best bet is
to figure out a way to automate lookup in the html documentation.


Carl Banks


From aahz at pythoncraft.com  Fri Jul 31 19:09:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 31 Jul 2009 16:09:16 -0700
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <h4vtis$n3e$1@panix3.panix.com>

In article <062813eb-7eec-4504-b32c-abadf02c3e38 at 12g2000pri.googlegroups.com>,
dandi kain  <dandi.kain at gmail.com> wrote:
>
>What is the functionality of __ or _ , leading or trailing an object ,
>class ot function ? Is it just a naming convention to note special
>functions and objects , or it really mean someting to Python ?

One more thing: if you have global module names with a single leading
underscore (e.g. "_foo"), they will not be loaded when you use

from <module> import *

However, "import *" is strongly discouraged for the most part.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From jeremy.cowles at gmail.com  Fri Jul 31 19:57:23 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Fri, 31 Jul 2009 16:57:23 -0700
Subject: Bug with Python, Cygwin and /dev/urandom?
Message-ID: <373cf0740907311657j3e65d94mbbb2eda9e0f94fb7@mail.gmail.com>

urllib2.py is crashes when calling randombytes(n). I run the following under
Cygwin (mimicking how randombytes works):

$ python
Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
[GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys,os
>>> os.path.exists("/dev/urandom")
True
>>> f = open("/dev/urandom")
>>> s = f.read(2)
>>> f.close()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IOError: [Errno 0] Error


Errno 0 is supposed to be impossible according to the following thread.
Apparently this same issue also causes Mercurial to crash:
http://www.nabble.com/hg-1.0-exits-with-abort:-Error-td19021833.html


Is this a bug?


--
Jeremy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/5b636dfe/attachment.html>

From rt8396 at gmail.com  Fri Jul 31 20:00:28 2009
From: rt8396 at gmail.com (r)
Date: Fri, 31 Jul 2009 17:00:28 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com> 
	<mailman.4078.1249077182.8015.python-list@python.org>
Message-ID: <dcf9e911-9935-48c9-b8bb-48d80ffcacd4@d32g2000yqh.googlegroups.com>

On Jul 31, 4:53?pm, Mark Lawrence <breamore... at yahoo.co.uk> wrote:
> r wrote:
> > On Jul 31, 4:16 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
> >> On Jul 31, 1:10 pm, kj <no.em... at please.post> wrote:
>
> >>> I'm pretty new to Python, and I like a lot overall, but I find the
> >>> documentation for Python rather poor, overall.
> >>> I'm sure that Python experts don't have this problem: they have
> >>> internalized some good ways to access the documentation, are
> >>> productive with it, and therefore have lost the ability to see why
> >>> the Python documentations is deficient for beginners.
> >> That may be so, but I do remember when I was a beginner myself and I
> >> had no issue with the documentation.
>
> > have you tried the new docs (>= 2.6) The interface has changed
> > drastically as to render itself completely useless. The old docs (<=
> > 2.5) --the ones i learned from-- where flawless.
>
> > @ Mark Lawrence
> > Have you clicked any of those links? try the "Tutorial start here" and
> > then try to find a menu of sorts. It seems you have to click "next" to
> > navigate. Thats pretty counter intuitive if you need to get to page
> > 589!! Upon clicking the tutorial link in the OLD DOCS, you where
> > presented with a nice menu for concise navigation.
>
> Yes. ?Works perfectly as evidenced by the fact that this evening I've
> checked data on the cProfile, pstats and array modules.
>
> --
> Kindest regards.
>
> Mark Lawrence.

Hold the phone... You checked data on modules using the "Tutorial
Start Here" link? Would not the "Global Module Index" be more, shall
we say, "informative"?


From kee at kagi.com  Fri Jul 31 20:12:43 2009
From: kee at kagi.com (Kee Nethery)
Date: Fri, 31 Jul 2009 17:12:43 -0700
Subject: Python docs disappointing - group effort to hire writers?
In-Reply-To: <109f1ff7-8fa9-40d3-80b4-1e90b5fc669c@d34g2000vbm.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
	<h4vq36$4ik$1@reader1.panix.com>
	<109f1ff7-8fa9-40d3-80b4-1e90b5fc669c@d34g2000vbm.googlegroups.com>
Message-ID: <756580E3-CFFA-404C-B66A-9F4281760C8E@kagi.com>

I too find the Python docs not very useful and it really slows down my  
learning curve.

I wonder if it would make sense to find good tech writers, get a  
quotes, and get some professionally written documentation WITH LOTS OF  
EXAMPLES added to the standard Python documentation tree.

I'd chip in money for that task. I've certainly spent enough buying  
Python books to where it would be very reasonable to chip in the cost  
of one book towards this project. Get enough people ... could be a  
great thing.

Even though it is not the version I use, I would suggest that the  
really detailed docs with lots of examples be written against the  
latest python version.

Just a thought.

Kee Nethery


From martin.hellwig at dcuktec.org  Fri Jul 31 20:14:33 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Sat, 01 Aug 2009 01:14:33 +0100
Subject: Python docs disappointing
In-Reply-To: <h4vj45$5hl$1@reader1.panix.com>
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>

kj wrote:
<cut python has poor documentation explanation>

Well to a level I agree with you.

If you are totally new to programming
_and_
you won't/can't invest in educational material
_and_
have an adversity for looking up resources using a web browser
_and_ don't have the patience for trial and error
*then*
getting proficient with the language is almost impossible.

Sometimes some modules are completely incomprehensible for me and that 
is after I have looked at the docstrings, the python doc and examples 
found using Google. However usually after combining all three with a 
fair bit of experimenting I figure it out, to me that is fun I like that 
kind of puzzles but I am aware that this isn't the best possible situation.

Overall I would say a better situation would be if the standard python 
documentation would have an *extensive* 'pattern' section for each 
module much like, for example, Frederik Lundh did this with his tkinter 
documentation. Incorporating these patterns in the standard 
documentation would save you some jumping around sites and it is perhaps 
more 'trustworthy' coming from the source (pun intended).

I believe that the documentation is all ReST format, so there should be 
a way (if there isn't already) to display the extensive documentation 
from the interpreter directly for the module you are working with. As 
you probably noticed, I actually never bothered to look if this isn't 
already the case. Which is a good indication to how much it has actually 
bothered me.

Furthermore I like to add to my reply, which is already longer then I 
anticipated at first, the thing I don't agree with you is the following 
(and comparative in nature): Compared to all other 'popular' languages I 
find Python actually very, very good documented and if you can't learn 
Python using the available documentation and on-line resources I think 
it is unlikely you can learn any other language, whether this is a 
programming language or a natural language. Actually, I should have 
replaced 'any' with 'anything' followed by a full stop.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From breamoreboy at yahoo.co.uk  Fri Jul 31 20:20:32 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Sat, 01 Aug 2009 01:20:32 +0100
Subject: Python docs disappointing
In-Reply-To: <dcf9e911-9935-48c9-b8bb-48d80ffcacd4@d32g2000yqh.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>	<4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>
	<mailman.4078.1249077182.8015.python-list@python.org>
	<dcf9e911-9935-48c9-b8bb-48d80ffcacd4@d32g2000yqh.googlegroups.com>
Message-ID: <h501nq$s2k$1@ger.gmane.org>

r wrote:
> On Jul 31, 4:53 pm, Mark Lawrence <breamore... at yahoo.co.uk> wrote:
>> r wrote:
>>> On Jul 31, 4:16 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
>>>> On Jul 31, 1:10 pm, kj <no.em... at please.post> wrote:
>>>>> I'm pretty new to Python, and I like a lot overall, but I find the
>>>>> documentation for Python rather poor, overall.
>>>>> I'm sure that Python experts don't have this problem: they have
>>>>> internalized some good ways to access the documentation, are
>>>>> productive with it, and therefore have lost the ability to see why
>>>>> the Python documentations is deficient for beginners.
>>>> That may be so, but I do remember when I was a beginner myself and I
>>>> had no issue with the documentation.
>>> have you tried the new docs (>= 2.6) The interface has changed
>>> drastically as to render itself completely useless. The old docs (<=
>>> 2.5) --the ones i learned from-- where flawless.
>>> @ Mark Lawrence
>>> Have you clicked any of those links? try the "Tutorial start here" and
>>> then try to find a menu of sorts. It seems you have to click "next" to
>>> navigate. Thats pretty counter intuitive if you need to get to page
>>> 589!! Upon clicking the tutorial link in the OLD DOCS, you where
>>> presented with a nice menu for concise navigation.
>> Yes.  Works perfectly as evidenced by the fact that this evening I've
>> checked data on the cProfile, pstats and array modules.
>>
>> --
>> Kindest regards.
>>
>> Mark Lawrence.
> 
> Hold the phone... You checked data on modules using the "Tutorial
> Start Here" link? Would not the "Global Module Index" be more, shall
> we say, "informative"?

You asked "Have you clicked any of those links?".  I answered yes since 
they all work.  I usually navigate to module data via the index tab as I 
find this the easiest way.  I'm sure other people prefer the global 
module index.  Six of one, half a dozen of the other?

-- 
Kindest regards.

Mark Lawrence.



From aahz at pythoncraft.com  Fri Jul 31 20:39:20 2009
From: aahz at pythoncraft.com (Aahz)
Date: 31 Jul 2009 17:39:20 -0700
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
Message-ID: <h502ro$3n2$1@panix3.panix.com>

In article <h4vnm4$jvi$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>In <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4 at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevidence at gmail.com> writes:
>>
>>(omg you have to use a *mouse*)
>
>That's precisely the point.  There's a huge number of programmers out
>there who, like me, *hate* to use the mouse while they're coding.  It
>is truly disappointing to us that the developers of Python chose to
>completely disregard this constituency.

That's why I use Lynx on a local copy of the Python docs.  Next question?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From pfeldman at verizon.net  Fri Jul 31 20:42:57 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 31 Jul 2009 17:42:57 -0700 (PDT)
Subject: possible to round number and convert to string?
In-Reply-To: <4a737350$0$28514$4fafbaef@reader2.news.tin.it>
References: <24763821.post@talk.nabble.com>
	<4a737350$0$28514$4fafbaef@reader2.news.tin.it>
Message-ID: <24764948.post@talk.nabble.com>


This was very close to what I wanted.  Thanks!  My final code looks like
this:

def num2str(x,f=4):
   """Convert x (int or float) to a string with f digits to right of
   the decimal point.  f may be zero or negative, in which case the decimal
   point is suppressed."""
   s= str(round(x,f))
   if f<=0:
      # Delete decimal point:
      i= s.find('.')
      if i>0: s= s[:i]
   return s
-- 
View this message in context: http://www.nabble.com/possible-to-round-number-and-convert-to-string--tp24763821p24764948.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 20:46:22 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 21:46:22 -0300
Subject: threads check socket
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
	<mailman.4055.1249061007.8015.python-list@python.org>
	<7b3247b0-4c85-4290-9de2-41fc45348d3d@z4g2000prh.googlegroups.com>
Message-ID: <op.uxykfkitx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 14:42:29 -0300, NighterNet <darkneter at gmail.com>  
escribi?:
> On Jul 31, 10:23?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>> En Fri, 31 Jul 2009 13:35:10 -0300, NighterNet <darkne... at gmail.com>  
>> escribi?:

>> > I been trying to find a way to check the socket is open or not. The
>> > thread are in a group and loop if the sockets are open. If they are
>> > not open delete the thread and remove the group. I need on this.
>>
>> What means an "open socket"? Do you want to detect whether the other  
>> side ?
>> closed the connection? In that case reading from the socket returns an ?
>> empty string.
>>
>> Regarding the "threads in a group", I don't understand what you mean.  
>> But ?
>> in general, you don't delete a thread, you just return from its run() ?
>> method and the thread finishes execution.
>
> Thread added into the array.

Which array?

> Well this thread when user leave the
> server want to make sure it not in used so that I can reuse it some
> how or move into another array.

Sorry but it's hard to help if you don't provide enough background. Looks  
like you're developing a game server; maybe this story is relevant to you:
http://comments.gmane.org/gmane.comp.python.general/627319

Assuming you're talking about TCP: when the client closes the connection  
gracefully, you get an empty string '' when reading from the socket. If  
the client loses the connection abruptly (the power goes down, the network  
is broken, the process is killed...) you get no indication of that. You  
may need to implement some mechanism (a PING? query/response, or perhaps  
the client must send an "I'm alive!" message once each N minutes; no  
answer means it's down and the server closes the connection).

> Need to know the thread speed that need for game server timer to
> control it. Don't want it too fast or slow for the game server.
> fps = 30
> 	def run(self):
> 		while True:
> 			self.gametime += 1
> 			if self.gametime > 10000000/fps:
> 				self.gametime = 0;

What's this code used for, apart from sucking lots of CPU power?

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 21:02:56 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 22:02:56 -0300
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
	<mailman.4067.1249070631.8015.python-list@python.org>
	<b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>
Message-ID: <op.uxyk66p8x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 18:58:43 -0300, bfrederi <brfredericks at gmail.com>  
escribi?:

> So what if I used a different encoding that isn't ASCII? Like UTF-8?
> Would that give me lengths that are multiples of 4 based on how the
> characters are represented? Or would I still need to pad with '='?

It doesn't matter, a base64-encoded string contains only ASCII characters.
How are you encoding the text? base64.b64encode does the padding for you,  
so you don't have to worry about that. Do as P. Otten suggests, try to  
send some known text and see what you actually get on the server. Most  
likely you'll find another problem (like trying to decode the complete  
HTTP response instead of just the entity body, or some other stupid  
mistake :) ).

-- 
Gabriel Genellina



From nagle at animats.com  Fri Jul 31 21:32:49 2009
From: nagle at animats.com (John Nagle)
Date: Fri, 31 Jul 2009 18:32:49 -0700
Subject: Module updating plans for Python 3.1: feedparser, MySQLdb
Message-ID: <4a739a96$0$1615$742ec2ed@news.sonic.net>

    Any progress on updating feedparser and MySQLdb for Python 3.x in the
foreseeable future?

    Feedparser shouldn't be that hard; it's just that nobody is working on it.
MySQLdb is known to be hard, and that may be a while.

				John Nagle


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 21:46:12 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 01 Aug 2009 01:46:12 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>
	<mailman.4060.1249065676.8015.python-list@python.org>
Message-ID: <008f7990$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 20:41:12 +0200, Emmanuel Surleau wrote:

>> We don't actually *declare* that something is constant and then have
>> that declaration ignored. Python doesn't lie to us, although (as in any
>> language) a programmer might.
> 
> You could say that Ruby doesn't either, 

Well you could say a lot of things. Admittedly you don't need a separate 
"constant" declaration, but creating a variable name with an initial 
uppercase letter is sufficient to make it a (supposed) constant:

irb(main):049:0* Thing = 5
=> 5
irb(main):050:0> Thing = 7
(irb):50: warning: already initialized constant Thing
=> 7

As you can see, Ruby (well, irb at least) considers that Thing is a 
constant, and then goes ahead and changes it anyway.

Apart from the use of an arbitrary naming convention instead of an 
explicit "make this constant" declaration, and the feeble way Ruby 
capitulates when you change it, I think having actual write-once 
constants is actually a plus.


> you just need to read the
> documentation. Ruby's unwritten motto is "flexibility ?ber alles". In
> this regard, it is consistent (1). 

"It's consistent in its inconsistency" sort of thing perhaps?


> Not much is really bolted down in
> Ruby. You get encapsulation, but it's so easy to break that it's mostly
> symbolic. 

Out of curiosity, can you read/write class and instance attributes from 
outside the class without using a getter/setter?



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 21:48:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 01 Aug 2009 01:48:09 GMT
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
Message-ID: <008f7a05$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 21:28:36 +0000, kj wrote:

> In <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4 at g19g2000vbi.googlegroups.com>
> Carl Banks <pavlovevidence at gmail.com> writes:
> 
>>(omg you have to use a
>>*mouse*)
> 
> That's precisely the point.  There's a huge number of programmers out
> there who, like me, *hate* to use the mouse while they're coding.


Complain to the developers of your web browser then. Or use a different 
web browser.


> It is
> truly disappointing to us that the developers of Python chose to
> completely disregard this constituency.

Python is open source software developed by a community of volunteers, so 
*you* are one of the developers of Python. You have an itch that needs 
scratching. Solve it yourself, and release it to the wider community, 
don't expect somebody else to do so.

Nobody is entitled to any functionality in Python. You can ask for it 
nicely, and if somebody thinks it's a good idea, and have nothing better 
to do, they may code it out of the goodness of their heart. Or you can do 
it yourself, or you can pay somebody to do it if you don't have the 
technical skill yourself. Or you can do without.


> This is one area in which Perl still whips Python...

If so, it's because Perl has more people who understand that the way to 
get something done is to do it, rather than whining about it.



-- 
Steven


From dciphercomputing at gmail.com  Fri Jul 31 21:53:47 2009
From: dciphercomputing at gmail.com (Simon)
Date: Fri, 31 Jul 2009 18:53:47 -0700 (PDT)
Subject: Newbie Question regarding __init__()
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
	<mailman.4058.1249065239.8015.python-list@python.org>
Message-ID: <ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>

Hi

So should the dcObject class include the "self" as well since I have
not defined an __init__ method in dcCursor?

Simon



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 22:06:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 23:06:39 -0300
Subject: Bug with Python, Cygwin and /dev/urandom?
References: <373cf0740907311657j3e65d94mbbb2eda9e0f94fb7@mail.gmail.com>
Message-ID: <op.uxyn5dr8x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 20:57:23 -0300, Jeremy Cowles  
<jeremy.cowles at gmail.com> escribi?:

> urllib2.py is crashes when calling randombytes(n). I run the following  
> under
> Cygwin (mimicking how randombytes works):
>
> $ python
> Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
> [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import sys,os
>>>> os.path.exists("/dev/urandom")
> True
>>>> f = open("/dev/urandom")
>>>> s = f.read(2)
>>>> f.close()
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> IOError: [Errno 0] Error
>
>
> Errno 0 is supposed to be impossible according to the following thread.
> Apparently this same issue also causes Mercurial to crash:
> http://www.nabble.com/hg-1.0-exits-with-abort:-Error-td19021833.html
>
>
> Is this a bug?

It seems so, but not necesarily a Python one; it might be a bug in cygwin  
instead.
If not already reported, file a bug at http://bugs.python.org/

-- 
Gabriel Genellina



From python.list at tim.thechases.com  Fri Jul 31 22:39:31 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 31 Jul 2009 21:39:31 -0500
Subject: Python docs disappointing
In-Reply-To: <oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>
Message-ID: <4A73AAE3.1050209@tim.thechases.com>

Martin P. Hellwig wrote:
> kj wrote:
[excerpt of previously snipped content restored]
>> I'm sure that I can find a full description of this parameter if
>> I fire up Google, and search online.  In fact, more likely than
>> not, I'll find far more documentation than I want.  But my point
>> is that a programmer should not need to do this.  The full
>> documentation should be readily accessible directly through a few
>> keystrokes.
> 
> Well to a level I agree with you.
[snip]
> have an adversity for looking up resources using a web browser

It may not be an adversity for looking things up using a 
web-browser, but rather the need to access documentation offline. 
  Whether on an airplane or simply away from a wifi/landline 
connection, there are plenty of times I'm coding offline (another 
reason I'm happy to have DVCS tools).

This thread prompted me to go digging a little further, and all 
the online docs are available in downloadable format, but you 
have to start by going to the base docs and chasing down the 
"downloads" rabbit-hole.  Perhaps it would be easier if there 
were some sort of back-link from individual pages, referencing 
the downloadable format package.

Combined with the downloaded HTML version of the docs (there are 
PDFs too if you prefer), using a lightweight browser like 
lynx/links/dillo, and optionally adding htdig for local 
search/indexing, you can access (and search) the full docs offline.

-tkc







From sjmachin at lexicon.net  Fri Jul 31 22:41:30 2009
From: sjmachin at lexicon.net (John Machin)
Date: Fri, 31 Jul 2009 19:41:30 -0700 (PDT)
Subject: .dbf tables and Null
References: <mailman.4059.1249065525.8015.python-list@python.org>
Message-ID: <2f4d5719-6ca8-4ef2-8734-420b3044b1dc@l35g2000pra.googlegroups.com>

On Aug 1, 3:41?am, Ethan Furman <et... at stoneleaf.us> wrote:
> Mornin'! ?and a good one, too, I hope.
>
> Question for you...
>
> First part of the question: ?What is the general value in having Null
> capability for fields?

In general, in any database system, so that one can distinguish
between "the customer has no 'middle name'" ('') and "the customer's
'middle name' is unknown" (NULL).

>
> Second part: ?Is there a tangible difference between Null, and the
> nothing of 0, '', False, etc, in python?

0 is the zero thing, it is not nothing. False is not nothing.


>
> Third part: ?If there is a tangible difference, do those of us who use
> python and these old, refuse-to-die, .dbf files actually have need of,
> or have tables including, Null values?
>
> P.S. part (for John Machin, if he sees this ?;)
> Will the dbf package you are working on support Null values?

My philosophy when digging stuff out of arcane storages is to expose
what is found and leave any kludging/sanitising to the next layer.

For example, None is returned for an N (Number) field that's all
spaces; it's up to the caller to decide whether to treat None as zero,
raise an exception, pop up a data-collection dialogue box, ...

If you mean specifically the Visual Foxpro v3 _NullFlags hack, yes, it
already supports that, as well as the VFP9 abuse of that hack for
Varchar and Varbinary fields :-)


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 22:58:40 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 23:58:40 -0300
Subject: heapq "key" arguments
References: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>
	<1582f82e-34aa-4b66-b989-c9f8351a5f1c@o9g2000prg.googlegroups.com>
	<4f096546-36a1-4633-9a24-1265ce0929ce@q14g2000vbi.googlegroups.com>
Message-ID: <op.uxyqj2wwx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 16:38:01 -0300, Joshua Bronson <jabronson at gmail.com>  
escribi?:
> On Jul 31, 2:02?pm, Jonathan Gardner <jgard... at jonathangardner.net>  
> wrote:
>> On Jul 31, 10:44?am, Joshua Bronson <jabron... at gmail.com> wrote:

>> > Say I want to maintain a heap of (x, y) pairs sorted only by
>> > first coordinate. Without being able to pass key=itemgetter(0), won't
>> > heapifying a list of such pairs unnecessarily compare both
>> > coordinates?
>>
>> It will compare the second value only if the first values are equal.
>
> I don't see how that helps. That's not at all the same thing as being
> able to pass key=itemgetter(0).

Ok, it's not strictly the same, but usually it doesn't hurt. The heaqp  
module doesn't promise anything about equal elements: it may keep the  
original order, rearrange them at will, reverse them, whatever. So the  
element-wise comparison of tuples is as good as comparing only the first  
element - *except* when comparing the second element isn't cheap or has  
side effects or something like that. In that case, use a custom class to  
redefine comparison operators:

 from heapq import heapify, heappop

class tuplebyfirst(tuple):
     "tuple that sorts only on first element"
     def __lt__(self, other):
         return self[0]<other[0]

heap = [tuplebyfirst(x) for x in [(2, 3, 'A'), (1, 4, 'B'),
         (2, 5, 'C'), (2, 5, 'D'), (3, 0, 'E')]]
print heap
heapify(heap)
while heap:
     print heappop(heap)

Output:

[(2, 3, 'A'), (1, 4, 'B'), (2, 5, 'C'), (2, 5, 'D'), (3, 0, 'E')]
(1, 4, 'B')
(2, 5, 'C')
(2, 5, 'D')
(2, 3, 'A')
(3, 0, 'E')

The letters are just to recognize the original ordering.
(I've used an undocumented property: all heapq functions compare elements  
ONLY by using "<", in 2.6.2 at least. Defining all the other rich  
comparison methods doesn't change anything)

-- 
Gabriel Genellina



From ben+python at benfinney.id.au  Fri Jul 31 23:02:03 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 01 Aug 2009 13:02:03 +1000
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
	<3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>
	<337482f9-8ad9-4600-9cf4-39911f5368ac@h31g2000yqd.googlegroups.com>
Message-ID: <87ab2ktexg.fsf@benfinney.id.au>

BDZ <bdezonia at wisc.edu> writes:

> Unfortunately, although it has the calls I'd want, pysamba appears to
> be *nix only.

That's because Samba is *nix-only. If you want to use something knowing
that it's Samba, you are by definition working on *nix.

> I need something that will work under Windows.

In that case, forget the term ?samba?. What you want is the ability to
connect, *over a network*, to shares served via the SMB protocol suite.

Those shares might be implemented via Samba, MS Windows, or aything else
that can speak the SMB protocol suite. Your program, running on Windows,
should not need to care about Samba, only about the various SMB
protocols.

A search for ?site:pypi.python.org smb client? gets me directly to
<URL:http://pypi.python.org/pypi/PySmbClient/>. That's totally useless
to you though, unfortunately, since it depends on Samba installed ?
which you can't, by definition, on MS Windows.

> Is there a set of Python Windows functions (official or contributed)
> that might do what I need? (I'm new to Python)

Not that I know of. It would probably involve a Python wrapper around
the native MS Windows networking API, something which I'm not sure has
been done.

-- 
 \       ?Whenever you read a good book, it's like the author is right |
  `\   there, in the room talking to you, which is why I don't like to |
_o__)                                   read good books.? ?Jack Handey |
Ben Finney


From nat.williams at gmail.com  Fri Jul 31 23:13:05 2009
From: nat.williams at gmail.com (Nat Williams)
Date: Fri, 31 Jul 2009 22:13:05 -0500
Subject: Newbie Question regarding __init__()
In-Reply-To: <ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
	<mailman.4058.1249065239.8015.python-list@python.org>
	<ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>
Message-ID: <eb280f6e0907312013w165f5240w9bd5c7fbad8645e3@mail.gmail.com>

As MRAB described, ALL instance methods need to accept 'self' as a first
parameter, as that will be passed to them implicitly when they are called.
This includes __init__.  The name 'self' is just a commonly accepted
convention for the name of the instance object passed to methods.  You don't
have to call it that, but you really should.

Take a look at http://docs.python.org/tutorial/classes.html#class-objects
It might help shed some light on how methods and instances work.

One other thing.  I'm a little confused by the first line of
dcObject.__init__:

self.init_Pre() and self.init_Exec()

I suspect this does not do what you think it does.  init_Pre and init_Exec
will both be called by this expression (unless init_Pre throws an exception,
of course).  You're not getting anything here that you wouldn't by just
calling each method on a separate line, except just making it harder to
read.

Nat


On Fri, Jul 31, 2009 at 8:53 PM, Simon <dciphercomputing at gmail.com> wrote:

> Hi
>
> So should the dcObject class include the "self" as well since I have
> not defined an __init__ method in dcCursor?
>
> Simon
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/3f9a41d4/attachment.html>

From darkneter at gmail.com  Fri Jul 31 23:14:13 2009
From: darkneter at gmail.com (NighterNet)
Date: Fri, 31 Jul 2009 20:14:13 -0700 (PDT)
Subject: socket policy flash help
Message-ID: <04e26f53-5f51-476d-823e-47bfeed9b2a8@m7g2000prd.googlegroups.com>

I need help on the policy to able to let access to user to the server
once the policy access is finish. I been trying to find a good
example, but I got no luck. Using python version 3.1.

Here the code I tested but it not working.

if str(buff) == str("b\'<policy-file-request/>\\x00\'"):
				print ('policy FOUND >>> sending...')
				rawinput = str('<?xml version=\"1.0\"?><cross-domain-policy><allow-
access-from domain=\"*\" to-ports=\"*\" /></cross-domain-policy>')
				print (rawinput)
				b = bytes ( ord(c) for c in rawinput)
				self.sockfd.send(b);


From tjreedy at udel.edu  Fri Jul 31 23:18:35 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 23:18:35 -0400
Subject: Python docs disappointing
In-Reply-To: <4A73AAE3.1050209@tim.thechases.com>
References: <h4vj45$5hl$1@reader1.panix.com>	<oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>
	<4A73AAE3.1050209@tim.thechases.com>
Message-ID: <h50c6a$dgf$1@ger.gmane.org>

Tim Chase wrote:

> It may not be an adversity for looking things up using a web-browser, 
> but rather the need to access documentation offline.  Whether on an 
> airplane or simply away from a wifi/landline connection, there are 
> plenty of times I'm coding offline (another reason I'm happy to have 
> DVCS tools).

This is one area where Windows users seems to have an advantage. The 
standard installer includes the doc set as a Windows help file. I often 
keep that open in one window while programming in others. I only later 
discovered that this was a copy of the online docs ;-), which I only use 
to check the in-development version before submitting a doc bug.



From ben+python at benfinney.id.au  Fri Jul 31 23:21:05 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 01 Aug 2009 13:21:05 +1000
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<h4vtis$n3e$1@panix3.panix.com>
Message-ID: <873a8cte1q.fsf@benfinney.id.au>

aahz at pythoncraft.com (Aahz) writes:

> One more thing: if you have global module names with a single leading
> underscore (e.g. "_foo"), they will not be loaded when you use
> 
> from <module> import *
> 
> However, "import *" is strongly discouraged for the most part.

Dude, that's exactly the ?underscore has an effect on import but as a
beginner don't worry about it? that I avoided drawing attention to. The
explanation was just fine without that. But no, you have to find a way
to *contribute*, don't you?

Things were different before all these new-fangled changes, I say. Get
off my lawn.

-- 
 \       ?I love and treasure individuals as I meet them, I loathe and |
  `\     despise the groups they identify with and belong to.? ?George |
_o__)                                                     Carlin, 2007 |
Ben Finney


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 23:22:35 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 01 Aug 2009 00:22:35 -0300
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<200907312048.03922.emmanuel.surleau@gmail.com>
	<h4vi6u$ms8$1@ger.gmane.org>
	<200907312226.59027.emmanuel.surleau@gmail.com>
Message-ID: <op.uxyrnxfcx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 17:26:58 -0300, Emmanuel Surleau  
<emmanuel.surleau at gmail.com> escribi?:
> On Friday 31 July 2009 21:55:11 Terry Reedy wrote:

>> The word tuple comes from relational databases as a generalization of
>> single, double, triple, quadruple, quintuple, sextuple, sestuple,
>> octuple, etc. A tuple is a data record with a fixed number of fields
>> with individual meaning. There is nothing about homogeneity of data type
>> in that definition. A triple of floats is legitimately a tuple when each
>> is a coordinate (the individual meanings). In other contexts, the same
>> triple might properly be a list (such as of heights of people
>> arbitrarily ordered).
>
> My understanding is that, in this context, it's not so much data types  
> which
> are heterogeneous, but the semantic meaning of the data. For instance, a  
> tuple
> containing (first_name, last_name, address) would be a "legitimate"  
> tuple, but
> not a tuple containing (address, address, address), which, if we follow
> Guido's philosophy, ought to be represented as a list.

Note that years ago the distinction was much stronger: tuples had NO  
methods at all. All you could do with a tuple was: len(t), t[i], t1+t2,  
t*n, e in t, for e in t
Being so "crippled", thinking of tuples just as immutable lists probably  
wasn't so natural.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 23:31:25 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 01 Aug 2009 00:31:25 -0300
Subject: Newbie Question regarding __init__()
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
	<mailman.4058.1249065239.8015.python-list@python.org>
	<ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>
Message-ID: <op.uxyr2nemx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 22:53:47 -0300, Simon <dciphercomputing at gmail.com>  
escribi?:

> So should the dcObject class include the "self" as well since I have
> not defined an __init__ method in dcCursor?

Every method that you define takes "self" as its first argument.
Every method that you want to call on the current instance must be  
qualified by self.methodname(argu, ments) -- it is not different from  
anotherobject.methodname(...)
Every attribute that you want to access from the current instance must be  
qualified too: self.attributename
There is no implicit self/this in Python as in other languages.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 23:56:43 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 01 Aug 2009 00:56:43 -0300
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
	<3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>
	<337482f9-8ad9-4600-9cf4-39911f5368ac@h31g2000yqd.googlegroups.com>
Message-ID: <op.uxys2nykx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 13:33:45 -0300, BDZ <bdezonia at wisc.edu> escribi?:
> On Jul 30, 4:41?pm, Lo?c Domaign? <loic.domai... at googlemail.com>
> wrote:

>> > Hello. I have written a Python 3.1 script running on Windows that uses
>> > os.path.exists() to connect to network shares. If the various network
>> > shares require different user account and password combos than the
>> > account the script is running under the routine returns false. I need
>> > something like os.samba.path.exists(username,password,path). Does
>> > anyone have a suggestion on how I can accomplish what I need to do in
>> > Python?
>>
>> Could the Python Samba module PySamba be interesting for  
>> you?http://sourceforge.net/projects/pysamba/
>
> Unfortunately, although it has the calls I'd want, pysamba appears to
> be *nix only. I need something that will work under Windows. Is there
> a set of Python Windows functions (official or contributed) that might
> do what I need? (I'm new to Python)

SAMBA is a Linux implementation of the SMB protocol, natively supported on
Windows. You may use the pywin32 package (available on sourceforge.net) to
call the WNetAddConnection2 Windows function:
http://msdn.microsoft.com/en-us/library/aa385413(VS.85).aspx

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Wed Jul  1 00:15:06 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 01 Jul 2009 01:15:06 -0300
Subject: invoking a method from two superclasses
References: <mailman.8861.1246401585.8014.python-list@python.org>
	<p06240807c6705db3787d@[10.0.1.221]>
Message-ID: <op.uwdffgffx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 30 Jun 2009 21:34:02 -0300, Mitchell L Model  
<MLMLists at comcast.net> escribi?:

> Allow me to add to my previous question that certainly the superclass
> methods can be called explicitly without resorting to super(), e.g.:
>
>     class C(A, B):
>         def __init__(self):
>             A.__init__(self)
>             B.__init__(self)
>
> My question is really whether there is any way of getting around the
> explicit class names by using super() and if not, shouldn't the  
> documentation
> of super point out that if more than one class on the mro defines a  
> method
> only the first will get called?

super returns [a proxy to] the *next* class in the MRO chain; it may or  
may not be a superclass of C (it may be a sibling class instead). If you  
know that only A B and C are involved and no other subclass ever exists,  
yes, you can explicitely invoke A.__init__ and B.__init__. If not (and  
this covers the vast majority of cases) using super in all places is the  
only way to get correct results (for details, see the "Harmful" article by  
James Knight [1] that someone has already referenced)

Note that doing it right with __init__ is tricky: usually, cooperative  
methods share the same signature so the super() call just passes the same  
arguments to the next class in the chain. But isn't uncommon for __init__  
to have different signatures for different subclasses; the article [1]  
contains a recipe for this case.

> What's strange is that it specifically mentions diamond patterns, which  
> is an important caseto get right, but it doesn't show how.

The "typical superclass call" in the 2.6 docs is, uhm, typical :) - in  
principle you use it everywhere you have cooperative classes. For the sake  
of completeness I'll copy it here:

class C(A, B):
     def method(self, arg):
         super(C, self).method(arg)

(you may simply use super().method(arg) in Python 3). Every implementation  
of method() in the class hierarchy should contain a super call like above  
(well, it gets somewhat more complex due to error handling, but you get  
the idea...)

In addition to the "Harmful" document, consider reading the three-article  
series by M. Simionato [2] which explains the problem from a different  
point of view.

[1] Python's Super Considered Harmful
http://fuhm.net/super-harmful/

[2] http://www.artima.com/weblogs/viewpost.jsp?thread=236275

-- 
Gabriel Genellina



From nmartelaro at gmail.com  Wed Jul  1 00:51:37 2009
From: nmartelaro at gmail.com (Nik Martelaro)
Date: Wed, 1 Jul 2009 00:51:37 -0400
Subject: Streaming Webcam over network
Message-ID: <885d14c40906302151u57d7005n5532093d68d2c786@mail.gmail.com>

Hi eveyone,
I am working on a project that requires streaming video from a webcam over
LAN and displaying the live video on the remote computer. Basically, I am
creating a specialized video chat client. I can get really nice video
locally using VideoCapture and Pygame, however have only been able to send
pixel data and recreate a single image at the other end. Does anyone know of
a good video streaming module or any other way of doing this in Python?

Thanks for any help!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/c8a878ff/attachment-0001.html>

From rylesny at gmail.com  Wed Jul  1 00:52:52 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 30 Jun 2009 21:52:52 -0700 (PDT)
Subject: Making code run in both source tree and installation path
References: <mailman.2310.1246292443.8015.python-list@python.org>
Message-ID: <ca05a251-3fd3-4026-9f25-cf310844928c@j14g2000vbp.googlegroups.com>

On Jun 29, 12:20?pm, Javier Collado <javier.coll... at gmail.com> wrote:
> Hello,
>
> I would like to be able to run the main script in a python project
> from both the source tree and the path in which it's installed on
> Ubuntu. The script, among other things, imports a package which in
> turns makes use of some data files that contains some metadata that is
> needed in xml format.
>
> The source tree has an structure such as this one:
> setup.py
> debian/ (packaging files)
> src/ (source code)
> src/lib (package files)
> src/data (data files)
> src/bin (main script)
>
> However, when the project is installed using setup.py install, the
> directory structure is approximately this way:
> /usr/local/bin (main script)
> /usr/local/share/<project_name> (data files)
> /usr/local/lib/python2.x/dist-packages/<project_name> (library files)
>
> And when installing the code through a package, the structure is the
> same one, but removing "local".
>
> Hence, the data files aren't always in the same relative directories
> depending on we're executing code from the source tree or from the
> installation. To make it possible to run the code from both places,
> I've seen different approaches:
> - distutils trick in setup.py to modify the installed script (i.e.
> changing a global variable value) so that it has a reference to the
> data files location.
> - Heuristic in the package code to detect when it's being executed
> from the source tree and when it has been the installed
> - Just using an environment variable that the user must set according
> to his needs
>
> I guess that there are other options, for example, maybe using
> buildout. What would you say it's the best/more elegant option to
> solve this problem?
>
> Best regards,
> ? ?Javier

It's kludgey, but one option may be to try and use __file__ to figure
out where the script is installed. Something like os.path.dirname
(os.path.abspath(__file__)) could tell you if it's in src/ or in the
bin/ directory, and then data files could be found in the appropriate
place.

I like the distutils/variable option better. Your script is more
likely to still behave correctly when copied to another directory.
Plus its code definitely remains cleaner.


From gagsl-py2 at yahoo.com.ar  Wed Jul  1 00:54:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 01 Jul 2009 01:54:45 -0300
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
Message-ID: <op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 30 Jun 2009 22:52:18 -0300, Mag Gam <magawake at gmail.com> escribi?:

> I am very new to python and I am in the process of loading a very
> large compressed csv file into another format.  I was wondering if I
> can do this in a multi thread approach.

Does the format conversion involve a significant processing time? If not,  
the total time is dominated by the I/O time (reading and writing the file)  
so it's doubtful you gain anything from multiple threads.

> Here is the pseudo code I was thinking about:
>
> Let T  = Total number of lines in a file, Example 1000000 (1 million  
> files)
> Let B = Total number of lines in a buffer, for example 10000 lines
>
>
> Create a thread to read until buffer
> Create another thread to read buffer+buffer  ( So we have 2 threads
> now. But since the file is zipped I have to wait until the first
> thread is completed. Unless someone knows of a clever technique.
> Write the content of thread 1 into a numpy array
> Write the content of thread 2 into a numpy array

Can you process each line independently? Is the record order important? If  
not (or at least, some local dis-ordering is acceptable) you may use a few  
worker threads (doing the conversion), feed them thru a Queue object, put  
the converted lines into another Queue, and let another thread write the  
results onto the destination file.

import Queue, threading, csv

def convert(in_queue, out_queue):
   while True:
     row = in_queue.get()
     if row is None: break
     # ... convert row
     out_queue.put(converted_line)

def write_output(out_queue):
   while True:
     line = out_queue.get()
     if line is None: break
     # ... write line to output file

in_queue = Queue.Queue()
out_queue = Queue.Queue()
tlist = []
for i in range(4):
   t = threading.Thread(target=convert, args=(in_queue, out_queue))
   t.start()
   tlist.append(t)
output_thread = threading.Thread(target=write_output, args=(out_queue,))
output_thread.start()

with open("...") as csvfile:
   reader = csv.reader(csvfile, ...)
   for row in reader:
     in_queue.put(row)

for t in tlist: in_queue.put(None) # indicate end-of-work
for t in tlist: t.join() # wait until finished
out_queue.put(None)
output_thread.join() # wait until finished

-- 
Gabriel Genellina



From MLMLists at Comcast.net  Wed Jul  1 00:57:13 2009
From: MLMLists at Comcast.net (Mitchell L Model)
Date: Wed, 1 Jul 2009 00:57:13 -0400
Subject: invoking a method from two superclasses
Message-ID: <p0624080cc670986339c1@[10.0.1.221]>

[Continuing the discussion about super() and __init__]

The documentation of super points out that good design of diamond patterns require the methods to have the same signature throughout the diamond. That's fine for non-mixin classes where the diamond captures different ways of handling the same data. The classical example is 

	BufferedStram
	     / \
	  /       \
	/           \
     BufInputStrm    BufOutputStrm		both have buffers, but use them differentlyu
	\            /
 	  \        /
	    \    /
	RandomAccessStream		or something like that

The idea of the diamond is to have just one buffer, rather than the two buffers that would result in C++ without making the base classes virtual.  All four classes could define __init__ with the argument
filename, or whatever, and everything works fine.

The problems start with the use of mixins. In essence, mixins intentionally do NOT want to be part of diamond patterns. They are orthogonal to the "true" or "main" class hierarchy and just poke their heads in hear and there in that hierarchy. Moreover, a class could inherit from multiple mixins. Typical simple orthogonal mixins would be NamedObject, TrackedObject, LoggedObject, ColoredWidget, and other such 
names compounded from an adjective, participle, or gerund and a completely meaningless name such as Object or Thing and which classes typically manage one action or piece of state to factor it out from the many other classes that need it where the pattern of which classes need them does not follow the regular class hierarchy.  Suppose I have a class User that includes NamedObject, TrackedObject, and LoggedObject as base classes. (By Tracked I mean instances are automatically registered in a list or dictionary for use by class methods that search, count, or do other operations on them.)

The problem is that each mixin's __init__ is likely to have a different signature. User.__init__
would have arguments (self, name, log), but it would need to call each mixin class's __init__ with different arguments. Mixins are different than what the document refers to as cooperative multiple inheritance -- does that make them uncooperative multiple inheritance classes :-)? I think I'd be back to having to call each mixin class's __init__ explicitly:

	class User(NamedObject, TrackedObject, LoggedObject)
		def __init__(self, name, log):
			NamedObject.__init__(self, name)
			TrackedObject.__init__(self)
			LoggedObject.__init__(self, log)

This is not terrible. It seems somehow appropriate that because mixin use is "orthogonal" to the "real" inheritance hierarchy, they shouldn't have the right to use super() and the full mro (after all, who knows where the mro will take these calls anyway). And in many cases, two mixins will join into another (a NamedTrackedObject) for convenience, and then classes inheriting from that have one less init to worry about.

I suspect this problem is largely with __init__. All the other __special__ fns have defined argument lists and so can be used with diamond patterns, mixins, etc.

Does this all sound accurate?  (Again, not looking for design advice, just trying to ferret out the subtleties and implications of multiple inheritance and super().)


From rylesny at gmail.com  Wed Jul  1 01:00:10 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 30 Jun 2009 22:00:10 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org> 
	<Xf-dnUHy7ad9rtTXnZ2dnUVZ_rSdnZ2d@pdx.net>
Message-ID: <b1d86eff-c1a6-45b7-9784-9137f5e1c2a2@f33g2000vbm.googlegroups.com>

On Jun 29, 5:43?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>?and I personally wouldn't have it any other way.  Simulating a shell
> with hooks on its I/O should be so complicated that a "script kiddie"
> has trouble writing a Trojan.

+1 QOTW


From ldo at geek-central.gen.new_zealand  Wed Jul  1 01:07:47 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 17:07:47 +1200
Subject: Multi thread reading a file
References: <mailman.2420.1246413152.8015.python-list@python.org>
Message-ID: <h2eqv3$gpt$4@lust.ihug.co.nz>

In message <mailman.2420.1246413152.8015.python-list at python.org>, Mag Gam 
wrote:

> I am very new to python and I am in the process of loading a very
> large compressed csv file into another format.  I was wondering if I
> can do this in a multi thread approach.

Why bother?



From ldo at geek-central.gen.new_zealand  Wed Jul  1 01:19:30 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 17:19:30 +1200
Subject: Idioms and Anti-Idioms Question
References: <mailman.1932.1245644100.8015.python-list@python.org>
	<H0F%l.20231$y61.5030@news-server.bigpond.net.au>
	<slrnh402pc.deb.peter@box8.pjb.com.au>
	<mailman.2018.1245772229.8015.python-list@python.org>
Message-ID: <h2erl2$h7l$1@lust.ihug.co.nz>

In message <mailman.2018.1245772229.8015.python-list at python.org>, J. Cliff 
Dyer wrote:

> If the lines got separated, a leading + could disappear into its line
> without any errors showing up.  A trailing + would raise a syntax error.

Unless, of course, it was moved onto the previous line as part of whatever 
caused the separation of the lines. How would you guard against that?



From stefan_ml at behnel.de  Wed Jul  1 01:30:13 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Wed, 01 Jul 2009 07:30:13 +0200
Subject: Multi thread reading a file
In-Reply-To: <mailman.2426.1246424006.8015.python-list@python.org>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
Message-ID: <4a4af466$0$31328$9b4e6d93@newsspool4.arcor-online.net>

Gabriel Genellina wrote:
> En Tue, 30 Jun 2009 22:52:18 -0300, Mag Gam <magawake at gmail.com> escribi?:
> 
>> I am very new to python and I am in the process of loading a very
>> large compressed csv file into another format.  I was wondering if I
>> can do this in a multi thread approach.
> 
> Does the format conversion involve a significant processing time? If
> not, the total time is dominated by the I/O time (reading and writing
> the file) so it's doubtful you gain anything from multiple threads.

Well, the OP didn't say anything about multiple processors, so multiple
threads may not help wrt. processing time. However, if the file is large
and the OS can schedule the I/O in a way that a seek disaster is avoided
(although that's hard to assure with today's hard disk storage density, but
SSDs may benefit), multiple threads reading multiple partial streams may
still reduce the overall runtime due to increased I/O throughput.

That said, the OP was mentioning that the data was compressed, so I doubt
that the I/O bandwidth is a problem here. As another poster put it: why
bother? Run a few benchmarks first to see where (and if!) things really get
slow, and then check what to do about the real problem.

Stefan


From pavlovevidence at gmail.com  Wed Jul  1 01:37:19 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 30 Jun 2009 22:37:19 -0700 (PDT)
Subject: invoking a method from two superclasses
References: <mailman.8861.1246401585.8014.python-list@python.org> 
	<p06240807c6705db3787d@[10.0.1.221]>
	<mailman.2424.1246421638.8015.python-list@python.org>
Message-ID: <65fa395e-0ac1-4b64-9792-74323ecbecc8@a36g2000yqc.googlegroups.com>

On Jun 30, 9:15?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Tue, 30 Jun 2009 21:34:02 -0300, Mitchell L Model ?
> <MLMLi... at comcast.net> escribi :
>
> > Allow me to add to my previous question that certainly the superclass
> > methods can be called explicitly without resorting to super(), e.g.:
>
> > ? ? class C(A, B):
> > ? ? ? ? def __init__(self):
> > ? ? ? ? ? ? A.__init__(self)
> > ? ? ? ? ? ? B.__init__(self)
>
> > My question is really whether there is any way of getting around the
> > explicit class names by using super() and if not, shouldn't the ?
> > documentation
> > of super point out that if more than one class on the mro defines a ?
> > method
> > only the first will get called?
>
> super returns [a proxy to] the *next* class in the MRO chain; it may or ?
> may not be a superclass of C (it may be a sibling class instead).

It could be even a niece class.


Carl Banks


From sato.photo at gmail.com  Wed Jul  1 01:38:04 2009
From: sato.photo at gmail.com (sato.photo at gmail.com)
Date: Tue, 30 Jun 2009 22:38:04 -0700 (PDT)
Subject: Basic question from pure beginner
Message-ID: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>

I have been going through some Python Programming exercises while
following the MIT OpenCourseWare Intro to CS syllabus and am having
some trouble with the first "If" exercise listed on this page:

http://en.wikibooks.org/wiki/Python_Programming/Conditional_Statements#If_Exercises

I have been able to make the module quit after entering a password
three times, but can't get it to quit right away after the correct one
is entered.  I know this is really basic, please forgive me.  I have
no programming experience and have just started going through these
tutorials.

My code is here:

http://python.pastebin.com/m6036b52e

-daniel


From pavlovevidence at gmail.com  Wed Jul  1 02:04:15 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 30 Jun 2009 23:04:15 -0700 (PDT)
Subject: Making code run in both source tree and installation path
References: <mailman.2310.1246292443.8015.python-list@python.org>
Message-ID: <5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>

On Jun 29, 9:20?am, Javier Collado <javier.coll... at gmail.com> wrote:
> I've seen different approaches:
> - distutils trick in setup.py to modify the installed script (i.e.
> changing a global variable value) so that it has a reference to the
> data files location.


One of my biggest complaints about distutils is that it doesn't do
this, a limitation made worse by the fact that distutils allows you to
specify an alternate data file directory, but your scripts have no way
to know what that alternate directory is installed.  Which really
limits the usefulness of that functionality.

The most common way I've seen people work around this issue is to
throw their data files into the package directories.  Yuck.

At one point I hacked up a setup.py file to look in the distutils data
structure and pull out the data install location, and wrote out a
trivial python file listing that location.  (The distutils build data
structure is helpfully returned by setup function.)  I never felt good
about it, and it wouldn't work if the install was done in steps (such
as build as user, install as superuser).

If you care to navigate the murky internals of distutils to do this in
a more elegant way, more power to you, and if so I'd recommend doing
it that way.


> - Heuristic in the package code to detect when it's being executed
> from the source tree and when it has been the installed
> - Just using an environment variable that the user must set according
> to his needs

I guess I'd combine these two.  Make a sensible guess about where the
data files are by checking out the environment, but if the data files
aren't there (such as if the user installs to a different data
location) then they are responsible for setting an env variable or
config option.



> I guess that there are other options, for example, maybe using
> buildout. What would you say it's the best/more elegant option to
> solve this problem?

Another option is not to use distutils at all.  If you are writing an
application, I think that would be a good idea.  I don't think
applications really need to be located in site-packages.

If you have any C-extensions it might complicate this.


Carl Banks


From __peter__ at web.de  Wed Jul  1 03:01:44 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 01 Jul 2009 09:01:44 +0200
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
Message-ID: <h2f1kk$e9m$03$1@news.t-online.com>

sato.photo at gmail.com wrote:

> I have been going through some Python Programming exercises while
> following the MIT OpenCourseWare Intro to CS syllabus and am having
> some trouble with the first "If" exercise listed on this page:
> 
> 
http://en.wikibooks.org/wiki/Python_Programming/Conditional_Statements#If_Exercises
> 
> I have been able to make the module quit after entering a password
> three times, but can't get it to quit right away after the correct one
> is entered.  I know this is really basic, please forgive me.  I have
> no programming experience and have just started going through these
> tutorials.
> 
> My code is here:
> 
> http://python.pastebin.com/m6036b52e
> 
> -daniel

Some hints: 

(1) Have the while loop check for both the correct password and the number 
of tries. Pseudocode:

while <more tries allowed> and <password not entered correctly>:
   ...

(2) After the loop has terminated you can check whether the password was 
entered correctly and print the appropriate message.

Aside: you can't mix if...else with other statements

correct:

if cond:
   print "sunny"
else:
   print "cloudy"
print "weather"

wrong: 

if cond:
   print "norwegian"
print "blue" 
else: # syntax error, else must immediately follow the indented if-block:
   print "moon"

you could fix it like so:

if cond:
   print "norwegian"
print "blue"
if not cond:
    print "moon"

Peter



From wuwei23 at gmail.com  Wed Jul  1 03:06:38 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 00:06:38 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
Message-ID: <b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>

On Jul 1, 3:38?pm, "sato.ph... at gmail.com" <sato.ph... at gmail.com>
wrote:
> I have been able to make the module quit after entering a password
> three times, but can't get it to quit right away after the correct one
> is entered. ?

Not with the code you pasted, you haven't. There's a missing colon on
line 7 & line 9 isn't indented properly. It's always best if we're
referring to the same source when trying to help with a problem.

The problem you're having, though, has to do with the while loop and
the fact that it's only checking one condition: has the 'count'
counter been incremented to 3. What you need to do is _also_ check for
the success condition:

is_confirmed = False
while count != 3 or is_confirmed:
  guess = raw_input("Enter your password: ")
  guess = str(guess)
  if guess != password:
    print "Access Denied"
    count = count + 1
  else:
    print "Password Confirmed"
    is_confirmed = True

This also provides you with a nice boolean that shows whether or not
the password was confirmed, which may be useful for latter code.

However, whenever you want to loop a set number of times, it's usually
better to use a 'for' loop instead:

PASSWORD = 'qwerty'
MAXRETRY = 3
for attempt in xrange(MAXRETRY):
  guess = str(raw_input('Enter your password: '))
  is_complete = guess == PASSWORD
  if is_complete:
    print 'Password confirmed'
    break # this exits the for loop
  else:
    print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)

This saves you from the burden of creating, incrementing & testing
your own counter.

If there's anything here that isn't clear, please don't hesitate to
ask.


From sato.photo at gmail.com  Wed Jul  1 03:58:27 2009
From: sato.photo at gmail.com (sato.photo at gmail.com)
Date: Wed, 1 Jul 2009 00:58:27 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>
Message-ID: <49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>

Thank you for all of the help.  With your assistance and help from the
Python Tutor mailing list I was able to come up with the following
code:

password = "qwerty"
correct_password_given = False
guess = "0"
count = 0
while count != 3 and not correct_password_given :
   guess = raw_input("Enter your password: ")
   guess = str(guess)
   if guess != password:
       print "Access Denied"
       count = count + 1
   else:
       print "Password Confirmed"
       correct_password_given = True


If I understand it correctly, the function will continue to loop until
either the count == 3 or until correct_password_give = True,
satisfying the two conditions of the assignment, which were to lock a
user out after three failed password attempts and to print "Access
Granted" and end the module if the correct password is given.  Am I
understanding this correctly?

Thanks!

On Jul 1, 12:06?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 1, 3:38?pm, "sato.ph... at gmail.com" <sato.ph... at gmail.com>
> wrote:
>
> > I have been able to make the module quit after entering a password
> > three times, but can't get it to quit right away after the correct one
> > is entered. ?
>
> Not with the code you pasted, you haven't. There's a missing colon on
> line 7 & line 9 isn't indented properly. It's always best if we're
> referring to the same source when trying to help with a problem.
>
> The problem you're having, though, has to do with the while loop and
> the fact that it's only checking one condition: has the 'count'
> counter been incremented to 3. What you need to do is _also_ check for
> the success condition:
>
> is_confirmed = False
> while count != 3 or is_confirmed:
> ? guess = raw_input("Enter your password: ")
> ? guess = str(guess)
> ? if guess != password:
> ? ? print "Access Denied"
> ? ? count = count + 1
> ? else:
> ? ? print "Password Confirmed"
> ? ? is_confirmed = True
>
> This also provides you with a nice boolean that shows whether or not
> the password was confirmed, which may be useful for latter code.
>
> However, whenever you want to loop a set number of times, it's usually
> better to use a 'for' loop instead:
>
> PASSWORD = 'qwerty'
> MAXRETRY = 3
> for attempt in xrange(MAXRETRY):
> ? guess = str(raw_input('Enter your password: '))
> ? is_complete = guess == PASSWORD
> ? if is_complete:
> ? ? print 'Password confirmed'
> ? ? break # this exits the for loop
> ? else:
> ? ? print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
>
> This saves you from the burden of creating, incrementing & testing
> your own counter.
>
> If there's anything here that isn't clear, please don't hesitate to
> ask.



From bruno.42.desthuilliers at websiteburo.invalid  Wed Jul  1 04:06:21 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 10:06:21 +0200
Subject: Learning to use decorators with classes
In-Reply-To: <mailman.2389.1246374159.8015.python-list@python.org>
References: <mailman.2389.1246374159.8015.python-list@python.org>
Message-ID: <4a4b18f2$0$15174$426a74cc@news.free.fr>

sk8in_zombi at yahoo.com.au a ?crit :
> --- On Tue, 30/6/09, Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> wrote:
> 
(snip)
>>
>> This can't work, and it's a FAQ FWIW - but since there's no
>> official c.l.py FAQ, we won't hold it against you !-)
>>
> 
> Can you please point me to the FAQ related to this snippet. I would be grateful.

Well, as I said, there's *no* c.l.py FAQ (I mean, any half-official text 
document listing frequently asked questions and their canonical 
answers), so I just can't provide any pointer here :-/

I guess we all here love talking about Python (and showing out our 
science, knowledge and wisdom) too much to maintain a FAQ !-)

(snip)



From bruno.42.desthuilliers at websiteburo.invalid  Wed Jul  1 04:26:16 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 10:26:16 +0200
Subject: Basic question from pure beginner
In-Reply-To: <49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
Message-ID: <4a4b1d9d$0$1525$426a74cc@news.free.fr>

sato.photo at gmail.com a ?crit :
> Thank you for all of the help.  With your assistance and help from the
> Python Tutor mailing list I was able to come up with the following
> code:
> 
> password = "qwerty"
> correct_password_given = False
> guess = "0"

You could just use None here:

   guess=None


> count = 0
> while count != 3 and not correct_password_given :
>    guess = raw_input("Enter your password: ")
>    guess = str(guess)

IIRC, raw_input() already returns a string !-)

>    if guess != password:
>        print "Access Denied"
>        count = count + 1

Or:
          count += 1

>    else:
>        print "Password Confirmed"
>        correct_password_given = True
> 
> 
> If I understand it correctly, the function will continue to loop until
> either the count == 3 or until correct_password_give =  True,

There are many ways to write a same boolean test, and some are easier to 
understand. Your test could be written:

   while not (count == 3 or correct_password_given) :
      # proceed

Does it answer your question ?-)

As a general rule:

* not A and not B <=> not (A or B)
* not A or not B  <=> not (A and B)


> satisfying the two conditions of the assignment, which were to lock a
> user out after three failed password attempts and to print "Access
> Granted" and end the module if the correct password is given.

Well, given your snippet, execution indeed terminates after either 
successful 'login' or 3 failed attempts, but that's mostly because 
there's no code to execute after the while loop...



From mr.spoon21 at gmail.com  Wed Jul  1 04:33:28 2009
From: mr.spoon21 at gmail.com (Mr.SpOOn)
Date: Wed, 1 Jul 2009 10:33:28 +0200
Subject: Getting input the scanf way
Message-ID: <8f67b6f80907010133t7f6e2d9eg9ffa3b927d540728@mail.gmail.com>

Hi,
I need to do some kind of interactive command line program.

I mean: I run the program, it asks me for input, I type something and
then I get the output or other questions.
I'm not sure what is the right way to achieve this.

Thanks,
Carlo


From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:33:45 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:33:45 +1200
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org>
	<Xf-dnUHy7ad9rtTXnZ2dnUVZ_rSdnZ2d@pdx.net>
	<b1d86eff-c1a6-45b7-9784-9137f5e1c2a2@f33g2000vbm.googlegroups.com>
Message-ID: <h2f719$njc$4@lust.ihug.co.nz>

In message <b1d86eff-
c1a6-45b7-9784-9137f5e1c2a2 at f33g2000vbm.googlegroups.com>, ryles wrote:

> On Jun 29, 5:43 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>
>>and I personally wouldn't have it any other way.  Simulating a shell
>> with hooks on its I/O should be so complicated that a "script kiddie"
>> has trouble writing a Trojan.
> 
> +1 QOTW

Trouble is, script kiddies, by definition, don't need to write anything. 
They just need to download something somebody else has already written.

-- 
Lawrence "I counter your +1 with my -1" D'Oliveiro



From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:39:06 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:39:06 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
Message-ID: <h2f7ba$njc$5@lust.ihug.co.nz>

In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o 
Valverde wrote:

> Simple example usage case: Insert string into data structure in sorted
> order if it doesn't exist, else retrieve it.

    the_set = set( ... )

    if str in the_set :
        ... "retrieval" case ...
    else :
        the_set.add(str)
    #end if

Want sorted order?

    sorted(tuple(the_set))

What could be simpler?



From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:40:19 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:40:19 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com> <4A4462E6.7080700@netcabo.pt>
	<50697b2c0906252323y60c237d0i44725e841ad29ed5@mail.gmail.com>
	<mailman.2144.1245999295.8015.python-list@python.org>
Message-ID: <h2f7dj$njc$6@lust.ihug.co.nz>

In message <mailman.2144.1245999295.8015.python-list at python.org>, Miles 
Kaufmann wrote:

> On Jun 26, 2009, at 2:23 AM, Chris Rebert wrote:
> 
>> That's pretty much the bisect module in a nutshell. It manipulates a
>> sorted list using binary search.
> 
> With O(n) insertions and removals, though.  A decent self-balancing
> binary tree will generally do those in O(log n).

For values of n below, say, a million, would you even notice the difference 
on modern hardware?



From http  Wed Jul  1 04:42:42 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 01:42:42 -0700
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
Message-ID: <7xeit0iykd.fsf@ruckus.brouhaha.com>

Joachim Str?mbergson <Joachim at Strombergson.com> writes:
> http://docs.python.org/library/hashlib.html
> I would suggest to use the SHA-256 in the library.

I agree with this.  We should even move towards supporting x509 and/or
gpg signatures in eggs, similar to signed .jar files.


From ldo at geek-central.gen.new_zealand  Wed Jul  1 04:43:10 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 01 Jul 2009 20:43:10 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<11eb0a6e-4e21-4a61-bf46-4221fd75dc8d@v15g2000prn.googlegroups.com>
	<mailman.2146.1246002542.8015.python-list@python.org>
Message-ID: <h2f7iv$njc$7@lust.ihug.co.nz>

In message <mailman.2146.1246002542.8015.python-list at python.org>, Jo?o Valverde wrote:

> But a dict can't be used to implement a (sorted) table ADT.

for key in sorted(the_dict.keys(), cmp = ... whatever ordering criteria you like ...) :
    ... do something with the_dict[key] ...
#end for




From R.Brodie at rl.ac.uk  Wed Jul  1 04:43:40 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Wed, 1 Jul 2009 09:43:40 +0100
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
Message-ID: <h2f7jt$j33$1@south.jnrs.ja.net>


"Joachim Str?mbergson" <Joachim at Strombergson.com> wrote in message 
news:mailman.2422.1246418400.8015.python-list at python.org...

> Even so, choosing md5 in 2009 for something that (hopefully) will be
> used in years is a bad design decision. It creates a dependency for to
> an algorithm that all sensible recommendations point you to move away
> from.

Why not write the field as algorithm:value?

e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4

Installers can fallback to using hashlib.new(), so you can plug in a new
algorithm without changing the PEP or the installer code. 




From http  Wed Jul  1 04:43:49 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 01:43:49 -0700
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com> <4A4462E6.7080700@netcabo.pt>
	<50697b2c0906252323y60c237d0i44725e841ad29ed5@mail.gmail.com>
	<mailman.2144.1245999295.8015.python-list@python.org>
	<h2f7dj$njc$6@lust.ihug.co.nz>
Message-ID: <7xab3oiyii.fsf@ruckus.brouhaha.com>

Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> writes:
> > With O(n) insertions and removals, though.  A decent self-balancing
> > binary tree will generally do those in O(log n).
> 
> For values of n below, say, a million, would you even notice the difference 
> on modern hardware?

Huh?  Yes, of course you'd notice, unless you were doing the operation
just once or something like that.


From http  Wed Jul  1 04:47:34 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 01:47:34 -0700
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
Message-ID: <7x3a9gdc2h.fsf@ruckus.brouhaha.com>

"Richard Brodie" <R.Brodie at rl.ac.uk> writes:
> Why not write the field as algorithm:value?
> e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4

This is reasonable, though I would deprecate md5 and sha1 already, and
start with sha256.


From iainking at gmail.com  Wed Jul  1 05:52:24 2009
From: iainking at gmail.com (Iain King)
Date: Wed, 1 Jul 2009 02:52:24 -0700 (PDT)
Subject: string character count
References: <58ceecd5-6d2c-44a9-8ef9-01feac5792f4@b9g2000yqm.googlegroups.com>
Message-ID: <b3f73ed0-b9cc-4052-a509-082398ffe8b2@i6g2000yqj.googlegroups.com>

On Jun 30, 6:27?pm, noydb <jenn.du... at gmail.com> wrote:
> If I have a string for a file name such that I want to find the number
> of characters to the left of the dot, how can that be done?
>
> I did it this way:
> x = "text12345.txt"
> dot = x.find('.')
> print dot
>
> Was curious to see what method others would use - helps me learn. ?I
> guess I was most curious to see if it could be done in one line.
>
> And, how would a char count be done with no dot -- like if the string
> were "textstringwithoutdot" or "no dot in text string"?

import os
root, ext = os.path.splitext(x)
print len(root)

or in one line (assuming you've imported os):
print len(os.path.splitext(x)[0])


Iain


From pm567426 at gmail.com  Wed Jul  1 06:00:32 2009
From: pm567426 at gmail.com (Pedram)
Date: Wed, 1 Jul 2009 03:00:32 -0700 (PDT)
Subject: A question about fill_free_list(void) function
Message-ID: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>

Hello community,
I'm reading the CPython interpreter source code,
first, if you have something that I should know for better reading
this source code, I would much appreciate that :)
second, in intobject.c file, I read the following code in
fill_free_list function that I couldn't understand:
<code>while (--q > p)
    Py_TYPE(q) = (struct _typeobject *)(q-1);
Py_TYPE(q) = NULL;
</code>
What does it mean?

Thanks.


From jerome.fuselier at gmail.com  Wed Jul  1 06:14:20 2009
From: jerome.fuselier at gmail.com (=?ISO-8859-1?Q?J=E9r=F4me_Fuselier?=)
Date: Wed, 1 Jul 2009 03:14:20 -0700 (PDT)
Subject: Problem with uuid package when embedding a python interpreter
References: <7d5cfbf0-38d5-4505-a93a-f321d0da74b8@c36g2000yqn.googlegroups.com>
	<mailman.2404.1246384974.8015.python-list@python.org>
Message-ID: <becd98c7-c486-4e29-aa75-88767c30e27c@l5g2000vbp.googlegroups.com>

On Jun 30, 7:02?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Tue, 30 Jun 2009 13:05:42 -0300, J?r?me Fuselier
> <jerome.fusel... at gmail.com> escribi?:
>
>
>
> > ? I've tried to import a script in an embedded python intrepreter but
> > this script fails when it imports the uuid module. I have a
> > segmentation fault in Py_Finalize().
>
> > #include "Python.h"
>
> > void test() {
> > ? ? Py_Initialize();
> > ? ? PyImport_Import(PyString_FromString("uuid"));
> > ? ? Py_Finalize();
> > }
>
> > main(int argc, char **argv)
> > {
> > ? ? for (i=0 ; i < 10; i++)
> > ? ? ? ? test();
> > }
>
> > For my application, I have to call Py_initialize and Py_Finalize
> > several times so factorizing them in the main function is not an easy
> > solution for me.
>
> Are you sure you can't do that? Not even using Py_IsInitialized? Try to
> avoid repeatedly calling Py_Initialize - won't work.
>
> Python 2.x does not have a way to "un-initialize" an extension module
> (that's a big flaw in Python design). Modules that contain global state
> are likely to crash the interpreter when used by the second time. (Python
> 3 attempts to fix that)
>
> --
> Gabriel Genellina

Hi Gabriel,
  Thanks for your response. I can modify my code to call
Py_IsInitialized which I didn't know before and this works well. The
problem is that I did not own the process which calls Py_Initialize
and Py_Finalize. I'm able to call Py_Initialize correctly but I can't
call Py_Finalize so this is not perfect.

At least I have a temporary solution which is not too bad.
Thanks,
Jerome


From jeanmichel at sequans.com  Wed Jul  1 06:33:43 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 01 Jul 2009 12:33:43 +0200
Subject: string character count
In-Reply-To: <4A4A51D7.6040602@mrabarnett.plus.com>
References: <58ceecd5-6d2c-44a9-8ef9-01feac5792f4@b9g2000yqm.googlegroups.com>
	<4A4A51D7.6040602@mrabarnett.plus.com>
Message-ID: <4A4B3B87.5040703@sequans.com>

MRAB wrote:
> noydb wrote:
>> If I have a string for a file name such that I want to find the number
>> of characters to the left of the dot, how can that be done?
>>
>> I did it this way:
>> x = "text12345.txt"
>> dot = x.find('.')
>> print dot
>>
>> Was curious to see what method others would use - helps me learn.  I
>> guess I was most curious to see if it could be done in one line.
>>
> >>> print "text12345.txt".find('.')
> 9
>
>> And, how would a char count be done with no dot -- like if the string
>> were "textstringwithoutdot" or "no dot in text string"?
>
> If there's no dot then find() returns -1.
>
> If you wanted to know the number of characters before the dot, if
> present, or in total otherwise, then you could use split():
>
> >>> len("text12345.txt".split(".", 1)[0])
> 9
> >>> len("textstringwithoutdot".split(".", 1)[0])
> 20
>

You may have problems with files containing multiple dots.
the os module provide nice & safe methods to parse a file path (on any 
system, mac os windows, linux).

 >>>f = "/dir1/dir2/test.log"
 >>>os.path.splitext(f)
('/dir1/dir2/test', '.log')

 >>>os.path.splitext(os.path.basename(f))
('test', '.log')

 >>>f2 = 'test.log'
 >>>os.path.splitext(os.path.basename(f2))
('test', '.log')



one safe way would be then
 >>> import os
 >>> x = "text12345.txt"
 >>> base , ext = os.path.splitext(os.path.basename(x))
 >>> print len(base)
9

Jean-Michel


From icanbob at gmail.com  Wed Jul  1 06:40:22 2009
From: icanbob at gmail.com (bobicanprogram)
Date: Wed, 1 Jul 2009 03:40:22 -0700 (PDT)
Subject: Passing parameters for a C program in Linux.
References: <7fa13d0c-d031-4576-8fee-a1c84af3e265@y7g2000yqa.googlegroups.com>
Message-ID: <eee0d931-fc6f-46fa-bb1f-1fd86242f126@b9g2000yqm.googlegroups.com>

On Jun 30, 6:46 am, "venutaurus... at gmail.com"
<venutaurus... at gmail.com> wrote:
> Hi all,
>        I have to write an automted script which will test my c
> program. That program when run will ask for the commands. For example:
>
> local-host# ./cli
> Enter 1 for add
> Enter 2 for sub
> Enter 3 for mul
> 1            -------Our option
> Enter two numbers
> 44 33  -------- Our option
> Result is 77
>
> As shown in the above example it lists all the options and waits for
> user input and once given, it does some operations and waits for some
> more. This has to be automated.
>
> Can someone give suggestions how to do this in Python (Linux Platform
> in particular).
>
> Thank you,
> Venu.


Take a look at the examples here:

http://www.icanprogram.com/06py/main.html

You can probably do what you want using the SIMPL toolkit quite
easily.

bob


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  1 07:41:07 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 01 Jul 2009 11:41:07 GMT
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <025b3cfd$0$20654$c3e8da3@news.astraweb.com>

On Wed, 01 Jul 2009 20:39:06 +1200, Lawrence D'Oliveiro wrote:

> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o
> Valverde wrote:
> 
>> Simple example usage case: Insert string into data structure in sorted
>> order if it doesn't exist, else retrieve it.
> 
>     the_set = set( ... )
> 
>     if str in the_set :
>         ... "retrieval" case ...

Not terribly useful, because there's no way of attaching any data to 
retrieve to the key. Apart from the case of interning strings (or other 
keys), you'd probably want a dict rather than a set:

if str in the_dict:
    return the_dict[str]
else:
    the_dict[str] = something_or_other


>     else :
>         the_set.add(str)
>     #end if


> Want sorted order?
> 
>     sorted(tuple(the_set))
> 
> What could be simpler?

Dropping the entirely superfluous creation of a tuple:

sorted(the_set)

That's a reasonable approach for small sets of data, but it isn't very 
useful if the_set contains 4GB of keys, because you have to duplicate the 
keys, then sort them. More effective would be a data structure that was 
always sorted. This has the further advantage that it's even simpler than 
sorted(the_set):

the_set



-- 
Steven


From magawake at gmail.com  Wed Jul  1 07:41:29 2009
From: magawake at gmail.com (Mag Gam)
Date: Wed, 1 Jul 2009 07:41:29 -0400
Subject: Multi thread reading a file
In-Reply-To: <op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <1cbd6f830907010441l3f953d13r6dd4e1a55dedc806@mail.gmail.com>

Thanks for the response Gabriel.



On Wed, Jul 1, 2009 at 12:54 AM, Gabriel
Genellina<gagsl-py2 at yahoo.com.ar> wrote:
> En Tue, 30 Jun 2009 22:52:18 -0300, Mag Gam <magawake at gmail.com> escribi?:
>
>> I am very new to python and I am in the process of loading a very
>> large compressed csv file into another format. ?I was wondering if I
>> can do this in a multi thread approach.
>
> Does the format conversion involve a significant processing time? If not,
> the total time is dominated by the I/O time (reading and writing the file)
> so it's doubtful you gain anything from multiple threads.

The format does inolve significant time processing each line.
>
>> Here is the pseudo code I was thinking about:
>>
>> Let T ?= Total number of lines in a file, Example 1000000 (1 million
>> files)
>> Let B = Total number of lines in a buffer, for example 10000 lines
>>
>>
>> Create a thread to read until buffer
>> Create another thread to read buffer+buffer ?( So we have 2 threads
>> now. But since the file is zipped I have to wait until the first
>> thread is completed. Unless someone knows of a clever technique.
>> Write the content of thread 1 into a numpy array
>> Write the content of thread 2 into a numpy array
>
> Can you process each line independently? Is the record order important? If
> not (or at least, some local dis-ordering is acceptable) you may use a few
> worker threads (doing the conversion), feed them thru a Queue object, put
> the converted lines into another Queue, and let another thread write the
> results onto the destination file.

Yes, each line can be independent. The original file is a time series
file which I am placing it into a Numpy array therefore I don't think
the record order is important.  The writing is actually done when I
place a value into a "dset" object.


Let me show you what I mean.
reader=csv.reader(open("100000.csv"))
for s,row in enumerate(reader):
 if s!=0 and s%bufsize==0:
      dset[s-bufsize:s] = t  #here is where I am writing the data to
the data structure. Using a range or broadcasting.

  #15 columns
 if len(row) != 15:
   break

 t[s%bufsize] = tuple(row)

#Do this all the way at the end for flushing.
if (s%bufsize != 0):
   dset[(s//bufsize)*bufsize:s]=t[0:s%bufsize]












>
> import Queue, threading, csv
>
> def convert(in_queue, out_queue):
> ?while True:
> ? ?row = in_queue.get()
> ? ?if row is None: break
> ? ?# ... convert row
> ? ?out_queue.put(converted_line)
>
> def write_output(out_queue):
> ?while True:
> ? ?line = out_queue.get()
> ? ?if line is None: break
> ? ?# ... write line to output file
>
> in_queue = Queue.Queue()
> out_queue = Queue.Queue()
> tlist = []
> for i in range(4):
> ?t = threading.Thread(target=convert, args=(in_queue, out_queue))
> ?t.start()
> ?tlist.append(t)
> output_thread = threading.Thread(target=write_output, args=(out_queue,))
> output_thread.start()
>
> with open("...") as csvfile:
> ?reader = csv.reader(csvfile, ...)
> ?for row in reader:
> ? ?in_queue.put(row)
>
> for t in tlist: in_queue.put(None) # indicate end-of-work
> for t in tlist: t.join() # wait until finished
> out_queue.put(None)
> output_thread.join() # wait until finished
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From ganesh.gbg at gmail.com  Wed Jul  1 07:48:11 2009
From: ganesh.gbg at gmail.com (gganesh)
Date: Wed, 1 Jul 2009 04:48:11 -0700 (PDT)
Subject: what will be best framework to select to develop Multi-Level 
	Marketing (network marketing) application in python?
Message-ID: <2f8c1642-6cad-4cd1-bc97-60c16aea31fd@g6g2000vbr.googlegroups.com>

hi group,
I have to build a software for Multi-Level Marketing (network
marketing),There are several Frameworks available in python ,i could
like to know the best Framework suitable to develop an application on
Multi-Level Marketing .
Thanks


From Ron.Barak at lsi.com  Wed Jul  1 07:48:40 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Wed, 1 Jul 2009 12:48:40 +0100
Subject: What are the limitations of cStringIO.StringIO() ?
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>

Hi,

I think I'm up against a limitation in cStringIO.StringIO(), but could not find any clues on the web, especially not in http://docs.python.org/library/stringio.html.

What I have is the following function:

    def concatenate_files(self,filename_array):
        import types

        f = cStringIO.StringIO()
        for filename in filename_array:
            log_stream = LogStream(filename)
            if not isinstance(log_stream, types.NoneType):
                try:
                    string_ = log_stream.input_file.read()
                except AttributeError, e:
                        sys.stderr.write("AttributeError: "+str(e)+"\n")
                        sys.stderr.write("log_stream: "+str(log_stream)+"\n")
            else:
                return(None)

            f.write(string_)
        return (f)

And, when the list of files - in filename_array - is pointing to long/large enough files, I get the exception:

Traceback (most recent call last):
  File "svm_ts_tool_in_progress.py", line 244, in OnSelectCell
    self.InspectorViewController(row,col)
  File "svm_ts_tool_in_progress.py", line 1216, in InspectorViewController
    self.InspectorePaneGetRecords(self.req_table, rec)
  File "svm_ts_tool_in_progress.py", line 1315, in InspectorePaneGetRecords
    log_stream = ConcatenatedLogStream(self.events_dict[req_table]["db_dict"].keys())
  File "c:\Documents and Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 31, in __init__
    self.input_file = self.concatenate_files(filename_array)
  File "c:\Documents and Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 47, in concatenate_files
    string_ = log_stream.input_file.read()
MemoryError

 1.  Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
 2.  Could you suggest a better way to create a string that contains the concatenation of several big files ?

Thanks,
Ron.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/7a56bd37/attachment-0001.html>

From thomas.bugzilla at gmx.net  Wed Jul  1 08:38:36 2009
From: thomas.bugzilla at gmx.net (Thomas)
Date: Wed, 01 Jul 2009 14:38:36 +0200
Subject: infinite recursion in pickle.load()
Message-ID: <h2fld6$2n4$1@news.web.de>

we regularly pickle and unpickle data from the same script (mostly 
dictionaries).

sometimes, a file written this way cannot be unpickled with 
pickle.load(), due to an infinite recursion with __getattr__ in 
codecs.py. here is a python2.5 stack trace excerpt:

/usr/local/lib/python2.5/pickle.py in load(file)
    1403
    1404 def load(file):
-> 1405     return Unpickler(file).load()
    1406
    1407 def loads(str):

/usr/local/lib/python2.5/pickle.py in load(self)
     891             while 1:
     892                 key = read(1)
--> 893                 dispatch[key](self)
     894         except _Stop, stopinst:
     895             return stopinst.value

/usr/local/lib/python2.5/pickle.py in load_build(self)
    1248         state = stack.pop()
    1249         inst = stack[-1]
-> 1250         setstate = getattr(inst, "__setstate__", None)
    1251         if setstate:
    1252             setstate(state)

/usr/local/lib/python2.5/codecs.py in __getattr__(self, name, getattr)
     328         """ Inherit all other methods from the underlying stream.
     329         """
--> 330         return getattr(self.stream, name)
     331
     332     def __enter__(self):

/usr/local/lib/python2.5/codecs.py in __getattr__(self, name, getattr)
     328         """ Inherit all other methods from the underlying stream.
     329         """
--> 330         return getattr(self.stream, name)
     331
     332     def __enter__(self):

     ...

The last frame repeats ad infinitum.

'inst' in the third frame is a <StreamWriter instance at 839b62c>

The problem is the same with cPickle.

This looks somewhat related to this Python issue, which is only about 
the exception reporting:
http://bugs.python.org/issue5508
(The title of the issue is the error you get when running our code in 
python2.6).

Any idea how to go about that?

T.


From gil.shinar at gmail.com  Wed Jul  1 08:56:12 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Wed, 1 Jul 2009 05:56:12 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
Message-ID: <794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>

On Jun 30, 7:48?pm, s... at pobox.com wrote:
> ? ? Gil> I have looked for a timeout parameter to limit the 4 minutes to
> ? ? Gil> something more reasonable but couldn't find one. ?Can anyone please
> ? ? Gil> help?
>
> ? ? Gil> BTW, I'm using Sybase.connect(<DBS name>, <Username>, <Password>,
> ? ? Gil> datetime='auto')
>
> We use the Sybase module where I work, but I've never encountered this
> problem (or a timeout parameter of any kind). ?At any rate, you'll probably
> have more luck asking on the python-sybase mailing list:
>
> ? ? python-sybase-m... at lists.sourceforge.net
>
> --
> Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> ? ? when i wake up with a heart rate below 40, i head right for the espresso
> ? ? machine. -- chaos @ forums.usms.org

Are you saying, that when you trying to connect to a sybase DBS server
and the DBS or the server is down, you get an error after a few
seconds and not after a few minutes? Which python version are you
using?

I'll try to ask in the python-sybase mailing list

Thanks


From gil.shinar at gmail.com  Wed Jul  1 09:08:01 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Wed, 1 Jul 2009 06:08:01 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
Message-ID: <5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com>

On Jul 1, 3:56?pm, eranlevi <gil.shi... at gmail.com> wrote:
> On Jun 30, 7:48?pm, s... at pobox.com wrote:
>
>
>
> > ? ? Gil> I have looked for a timeout parameter to limit the 4 minutes to
> > ? ? Gil> something more reasonable but couldn't find one. ?Can anyone please
> > ? ? Gil> help?
>
> > ? ? Gil> BTW, I'm using Sybase.connect(<DBS name>, <Username>, <Password>,
> > ? ? Gil> datetime='auto')
>
> > We use the Sybase module where I work, but I've never encountered this
> > problem (or a timeout parameter of any kind). ?At any rate, you'll probably
> > have more luck asking on the python-sybase mailing list:
>
> > ? ? python-sybase-m... at lists.sourceforge.net
>
> > --
> > Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> > ? ? when i wake up with a heart rate below 40, i head right for the espresso
> > ? ? machine. -- chaos @ forums.usms.org
>
> Are you saying, that when you trying to connect to a sybase DBS server
> and the DBS or the server is down, you get an error after a few
> seconds and not after a few minutes? Which python version are you
> using?
>
> I'll try to ask in the python-sybase mailing list
>
> Thanks

There's no such group as python-sybase :-(

Thanks


From pm567426 at gmail.com  Wed Jul  1 09:50:31 2009
From: pm567426 at gmail.com (Pedram)
Date: Wed, 1 Jul 2009 06:50:31 -0700 (PDT)
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
Message-ID: <dba78c8e-320e-4e19-a33b-f1d830de09d5@f10g2000vbf.googlegroups.com>

Oh... I got it! :)
I found this line in ctypes.h:
#define Py_TYPE(q) = ((PyObject *)(q))->ob_next;
So those lines are trying to set the blocks type from rear to front.

But I still don't know why after the while (when q is equal to p), the
Py_TYPE(q) set to NULL!


From sebastian.schabe at gmx.de  Wed Jul  1 10:51:47 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Wed, 01 Jul 2009 16:51:47 +0200
Subject: deleting certain entries in numpy array
Message-ID: <4a4b7763$1@news.fhg.de>

Hello everybody,

I'm new to python and numpy and have a little/special problem:

I have an numpy array which is in fact a gray scale image mask, e.g.:

mask =
array([[  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0, 255, 255, 255,   0,   0, 255,   0],
        [  0,   0, 255, 255, 255,   0,   0, 255,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0],
        [  0,   0,   0,   0,   0,   0,   0,   0,   0]], dtype=uint8)

and I have another array of (y, x) positions in that mask (first two 
values of each row):

pos =
array([[  3.,   2.,   0.,   0.],
        [  3.,   4.,   0.,   0.],
        [  5.,   2.,   0.,   0.],
        [  5.,   4.,   0.,   0.],
        [  6.,   2.,   0.,   0.],
        [  6.,   7.,   0.,   0.],
        [  0.,   0.,   0.,   0.],
        [  8.,   8.,   0.,   0.]])

and now I only want to keep all lines from 2nd array pos with those 
indices that are nonzero in the mask, i.e. line 3-6 (pos[2]-pos[5]).

F.e. line 4 in pos has the values (5, 4) and mask[5][4] is nonzero, so I 
want to keep it. While line 2 (pos[1]) has the values (4, 6) and 
mask[4][6] is zero, so shall be discarded.

I want to avoid a for loop (if possible!!!) cause I think (but don't 
know) numpy array are handled in another way. I think numpy.delete is 
the right function for discarding the values, but I don't know how to 
build the indices.



Maybe someone can help me with that or suggest which way to do this

Sebastian


From Frank.Aune at broadpark.no  Wed Jul  1 11:02:20 2009
From: Frank.Aune at broadpark.no (Frank Aune)
Date: Wed, 1 Jul 2009 17:02:20 +0200
Subject: logging module and binary strings
Message-ID: <200907011702.21450.Frank.Aune@broadpark.no>

Hello,

---- snip ----
>>> import logging
>>> logging.basicConfig(level=logging.DEBUG)
>>> x='\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>> x
'\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>> print x
?????
>>> logging.info(x)
Traceback (most recent call last):
  File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
    stream.write(fs % msg.encode("UTF-8"))
UnicodeDecodeError: 'ascii' codec can't decode byte 0xfe in position 10: 
ordinal not in range(128)
>>> logging.info(x, extra={'encoding':'utf-8'})
Traceback (most recent call last):
  File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
    stream.write(fs % msg.encode("UTF-8"))
UnicodeDecodeError: 'utf8' codec can't decode byte 0xfe in position 10: 
unexpected code byte

---- snip ----

Is there any way to log the above value of x "properly" using the python 
logging module? By properly I mean logging the value displayed when entering 
just x in the python shell and pressing enter. 

Regards,
Frank




From eric.pruitt at gmail.com  Wed Jul  1 11:17:31 2009
From: eric.pruitt at gmail.com (Eric Pruitt)
Date: Wed, 1 Jul 2009 10:17:31 -0500
Subject: Bytes, Strings, Encoding
Message-ID: <171e8a410907010817j715f1d5ye638ea4b2469afd9@mail.gmail.com>

Hello,

I am working on the subprocess.Popen module for Python 2.7 and am now moving
my changes over to Python 3.1 however I am having trouble with the whole
byte situation and I can't quite seem to understand how to go back and forth
between bytes and strings. I am also looking for the Python 3k equivalent
for the Python 2.X built-in buffer class.

One version of the file with my modifications can be found here  <
http://code.google.com/p/subprocdev/source/browse/subprocess.py?spec=svn5b570f8cbfcaae859091eb01b21b183aa5221af9&r=5b570f8cbfcaae859091eb01b21b183aa5221af9>.
Lines 1 - 15 are me attempting to get around certain changes between
Python 3.0 and Python 2.7. Further down on line 916, we have the function
"send" and "recv" in which I am having the most trouble with bytes and
strings.

Any help is appreciated. Feel free to comment on my blog
http://subdev.blogspot.com/ or reply to the last.

Thanks in advance,
Eric
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/fa346a3a/attachment-0001.html>

From Scott.Daniels at Acm.Org  Wed Jul  1 11:38:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 01 Jul 2009 08:38:58 -0700
Subject: invoking a method from two superclasses
In-Reply-To: <mailman.2423.1246419562.8015.python-list@python.org>
References: <mailman.8917.1246409702.8014.python-list@python.org>
	<mailman.2423.1246419562.8015.python-list@python.org>
Message-ID: <r6qdnZX9Do_xHNbXnZ2dnUVZ_hednZ2d@pdx.net>

 > Mitchell L Model wrote:

Sorry, after looking over some other responses, I went back and re-read
your reply.  I'm just making sure here, but:

 > Scott David Daniels wrote:
Below compressed for readability in comparison:
>>    class A:
>>        def __init__(self): super().__init__(); print('A')
>>    class B:
>>        def __init__(self): super().__init__(); print('B')
>>    class C(A, B):
>>        def __init__(self): super().__init__(); print('C')
>>    C()
>> And, if you are doing it with a message not available in object:

Renamed to disambiguate later discussion
>>    class root:
>>        def prints(self): print('root') # or pass if you prefer
>>    class D(root):
>>        def prints(self): super().prints(); print('D')
>>    class E(root):
>>        def prints(self): super().prints(); print('E')
>>    class F(D, E):
>>        def prints(self): super().prints(); print('F')
>>    F().prints()

> What I was missing is that each path up to and including the top of the diamond
> must include a definition of the method, along with super() calls to move the method
> calling on its way up.

Actually, not really true.  In the F through root example, any of the
"prints" methods except that on root may be deleted and the whole thing
works fine.  The rootward (closer to object) end must contain the method
in question, possibly only doing a pass as the action, and _not_ calling
super.  The other methods (those in D, E, and F above are all optional
(you can freely comment out those methods where you like), but each
should call super() in their bodies.

Note that you can also add a class:
     class G(E, D):
         def prints(self): super().prints(); print('G')
     G().prints()
Also note that the inheritances above can be "eventually inherits from"
as well as direct inheritance.

> Is this what the documentation means by "cooperative multiple inheritance"?

Yes, the phrase is meant to convey "No magic (other than super itelf) is
involved in causing the other methods to be invoked.  If you want "all"
prints methods called, make sure all but the last method do super calls.
Of course, any method that doesn't do the super call will be the last by
definition (no flow control then), but by putting the non-forwarding
version at or below the lower point of the diamond, the mro order
guarantees that you will have a "good" place to stop.

Think of the mro order as a solution to the partial order constraints
that a class must appear before any of its direct superclasses, and (by
implication) after any of its subclasses.

> If your correction of my example, if you remove super().__init__ from B.__init__
> the results aren't affected, because object.__init__ doesn't do anything and
> B comes after A in C's mro. However, if you remove super().__init__ from
> A.__init__, it stops the "supering" process dead in its tracks.

Removing the super from B.__init__ means that you don't execute
object.__init__.  It turns out that object does nothing in its __init__,
but without knowing that, removing the super from B.__init__ is also a
mistake.

So, you may well already have it all right, but as long as I'm putting
in the effort to get the "operational rules about using super" out, I
thought I'd fill in this last little bit.

--Scott David Daniels
Scott.Daniels at Acm.Org


From jenn.duerr at gmail.com  Wed Jul  1 11:45:40 2009
From: jenn.duerr at gmail.com (noydb)
Date: Wed, 1 Jul 2009 08:45:40 -0700 (PDT)
Subject: string character count
References: <58ceecd5-6d2c-44a9-8ef9-01feac5792f4@b9g2000yqm.googlegroups.com>
	<b3f73ed0-b9cc-4052-a509-082398ffe8b2@i6g2000yqj.googlegroups.com>
Message-ID: <54b554d3-c03e-40de-a02d-a176d0583cea@z28g2000vbl.googlegroups.com>

thanks everyone for all the ideas -- simple stuff, I know for you all,
but very helpful for me.


From jcd at sdf.lonestar.org  Wed Jul  1 11:48:23 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Wed, 01 Jul 2009 11:48:23 -0400
Subject: It's ...
In-Reply-To: <df0dea3d-691f-4f24-9a63-09fd59fbf229@b15g2000yqd.googlegroups.com>
References: <qjt4451snn47mr8qj3md1coi9a19tvt1v5@4ax.com>
	<mailman.2074.1245876142.8015.python-list@python.org>
	<df0dea3d-691f-4f24-9a63-09fd59fbf229@b15g2000yqd.googlegroups.com>
Message-ID: <1246463303.11768.0.camel@aalcdl07>

On Tue, 2009-06-30 at 13:24 -0700, Beni Cherniavsky wrote:
> On Jun 24, 11:40 pm, "J. Cliff Dyer" <j... at sdf.lonestar.org> wrote:
> > Also note that you can iterate over a file several times:
> >
> > f = open('foo.txt')
> > for line in f:
> >     print line[0]  # prints the first character of every line
> > for line in f:
> >     print line[1]  #prints the second character of every line
> >
> No, you can't.  The second loop prints nothing!
> A file by default advances forward.  Once you reach the end, you stay
> there.

You are, of course, absolutely right.  Sorry for the misinformation.

:(



From Scott.Daniels at Acm.Org  Wed Jul  1 11:49:31 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 01 Jul 2009 08:49:31 -0700
Subject: Multi thread reading a file
In-Reply-To: <mailman.2426.1246424006.8015.python-list@python.org>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
Message-ID: <dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>

Gabriel Genellina wrote:
> ...
> def convert(in_queue, out_queue):
>   while True:
>     row = in_queue.get()
>     if row is None: break
>     # ... convert row
>     out_queue.put(converted_line)

These loops work well with the two-argument version of iter,
which is easy to forget, but quite useful to have in your bag
of tricks:

     def convert(in_queue, out_queue):
         for row in iter(in_queue.get, None):
             # ... convert row
             out_queue.put(converted_line)

--Scott David Daniels
Scott.Daniels at Acm.Org


From petshmidt at googlemail.com  Wed Jul  1 12:05:37 2009
From: petshmidt at googlemail.com (someone)
Date: Wed, 1 Jul 2009 09:05:37 -0700 (PDT)
Subject: =?windows-1252?Q?getting_rid_of__=97?=
Message-ID: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>

Hello,

how can I replace '?' sign from string? Or do split at that character?
Getting unicode error if I try to do it:

UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
1: ordinal not in range(128)


Thanks, Pet

script is # -*- coding: UTF-8 -*-


From michele.simionato at gmail.com  Wed Jul  1 12:08:55 2009
From: michele.simionato at gmail.com (Michele Simionato)
Date: Wed, 1 Jul 2009 09:08:55 -0700 (PDT)
Subject: invoking a method from two superclasses
References: <mailman.8861.1246401585.8014.python-list@python.org> 
	<mailman.2416.1246408453.8015.python-list@python.org>
Message-ID: <8bc6afc1-21fc-40dd-ba7d-f0d549a7de93@24g2000yqm.googlegroups.com>

On Jul 1, 2:34?am, Mitchell L Model <MLMLi... at Comcast.net> wrote:
> I suspect we should have a Multiple Inheritance HOWTO, though details and
> recommendations would be controversial. I've accumulated lots of abstract
> examples along the lines of my question, using multiple inheritance both to
> create combination classes (the kinds that are probably best done with
> composition instead of inheritance) and mixins. I like mixins, and I like abstract
> classes. And yes I understand the horrors of working with a large component
> library that uses mixins heavily, because I've experienced many of them, going
> all the way back to Lisp-Machine Lisp's window system with very many combo
> classes such as FancyFontScrollingTitledMinimizableWindow, or whatever.
> Also, I understand that properties might be better instead of multiple inheritance
> for some situations. What I'm trying to do is puzzle out what the reasonable uses
> of multiple inheritance are in Python 3 and how classes and methods that follow
> them should be written.

You may be interest in my "Things to know about super":

http://www.artima.com/weblogs/viewpost.jsp?thread=236275
http://www.artima.com/weblogs/viewpost.jsp?thread=236278
http://www.artima.com/weblogs/viewpost.jsp?thread=237121


From robert.kern at gmail.com  Wed Jul  1 12:17:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 01 Jul 2009 11:17:31 -0500
Subject: Making code run in both source tree and installation path
In-Reply-To: <5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>
References: <mailman.2310.1246292443.8015.python-list@python.org>
	<5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>
Message-ID: <h2g26r$8lv$1@ger.gmane.org>

On 2009-07-01 01:04, Carl Banks wrote:
> On Jun 29, 9:20 am, Javier Collado<javier.coll... at gmail.com>  wrote:
>> I've seen different approaches:
>> - distutils trick in setup.py to modify the installed script (i.e.
>> changing a global variable value) so that it has a reference to the
>> data files location.
>
>
> One of my biggest complaints about distutils is that it doesn't do
> this, a limitation made worse by the fact that distutils allows you to
> specify an alternate data file directory, but your scripts have no way
> to know what that alternate directory is installed.  Which really
> limits the usefulness of that functionality.
>
> The most common way I've seen people work around this issue is to
> throw their data files into the package directories.  Yuck.

Huh. I always found that to be a more elegant solution than hardcoding the data 
location into the program at install-time.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python at mrabarnett.plus.com  Wed Jul  1 12:18:24 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 01 Jul 2009 17:18:24 +0100
Subject: Basic question from pure beginner
In-Reply-To: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
Message-ID: <4A4B8C50.4010202@mrabarnett.plus.com>

sato.photo at gmail.com wrote:
> I have been going through some Python Programming exercises while
> following the MIT OpenCourseWare Intro to CS syllabus and am having
> some trouble with the first "If" exercise listed on this page:
> 
> http://en.wikibooks.org/wiki/Python_Programming/Conditional_Statements#If_Exercises
> 
> I have been able to make the module quit after entering a password
> three times, but can't get it to quit right away after the correct one
> is entered.  I know this is really basic, please forgive me.  I have
> no programming experience and have just started going through these
> tutorials.
> 
> My code is here:
> 
> http://python.pastebin.com/m6036b52e
> 
raw_input() returns a string, so you don't need "guess = str(guess)".

The 'if' line should end with a colon.

Incrementing the count should probably be after the 'if' statement.

You can leave a loop prematurely with the 'break' statement.


From mail at timgolden.me.uk  Wed Jul  1 12:20:38 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 01 Jul 2009 17:20:38 +0100
Subject: No trees in the stdlib?
In-Reply-To: <h2f7ba$njc$5@lust.ihug.co.nz>
References: <mailman.2139.1245994218.8015.python-list@python.org>	<h21mgt$oav$1@panix3.panix.com>	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <4A4B8CD6.6050606@timgolden.me.uk>

Lawrence D'Oliveiro wrote:
> Want sorted order?
> 
>     sorted(tuple(the_set))

Not sure why you want the tuple () there, but
you probably knew that...

TJG


From python at mrabarnett.plus.com  Wed Jul  1 12:21:54 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 01 Jul 2009 17:21:54 +0100
Subject: No trees in the stdlib?
In-Reply-To: <h2f7ba$njc$5@lust.ihug.co.nz>
References: <mailman.2139.1245994218.8015.python-list@python.org>	<h21mgt$oav$1@panix3.panix.com>	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <4A4B8D22.3060308@mrabarnett.plus.com>

Lawrence D'Oliveiro wrote:
> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o 
> Valverde wrote:
> 
>> Simple example usage case: Insert string into data structure in sorted
>> order if it doesn't exist, else retrieve it.
> 
>     the_set = set( ... )
> 
>     if str in the_set :
>         ... "retrieval" case ...
>     else :
>         the_set.add(str)
>     #end if
> 
> Want sorted order?
> 
>     sorted(tuple(the_set))
> 
> What could be simpler?
> 
Why not just "sorted(the_set)"?


From charles at declareSub.com  Wed Jul  1 12:26:41 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Wed, 1 Jul 2009 12:26:41 -0400
Subject: Basic question from pure beginner
In-Reply-To: <49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
Message-ID: <1A63D369-87EF-4429-8C05-C1579C9BE71C@declareSub.com>

Let me offer a bit of editing.

First, using the condition count != 3 is perhaps risky.  A mistake or  
a change in logic in the loop body might result in an infinite loop.   
So instead I suggest

while count < 3...

Second, I'd suggest storing the value 3 in a variable with a name that  
describes it.

MaxAttempts = 3
while count < MaxAttempts

This suggests that you change the name 'count' to 'attemptcount'.

The variable 'guess' is used only inside the loop, so I suggest  
removing the assignment outside the loop.

Finally, I'd remove correct_password_given from the loop test, and  
replace it with a break statement when the correct password is entered.

password = "qwerty"
correct_password_given = False
attemptcount = 0
MaxAttempts = 3
while attemptcount < MaxAttempts:
   guess = raw_input("Enter your password: ")
   guess = str(guess)
   if guess != password:
       print "Access Denied"
       attemptcount = attemptcount + 1
   else:
       print "Password Confirmed"
       correct_password_given = True
       break


Charles Yeomans

On Jul 1, 2009, at 3:58 AM, sato.photo at gmail.com wrote:

> Thank you for all of the help.  With your assistance and help from the
> Python Tutor mailing list I was able to come up with the following
> code:
>
> password = "qwerty"
> correct_password_given = False
> guess = "0"
> count = 0
> while count != 3 and not correct_password_given :
>   guess = raw_input("Enter your password: ")
>   guess = str(guess)
>   if guess != password:
>       print "Access Denied"
>       count = count + 1
>   else:
>       print "Password Confirmed"
>       correct_password_given = True
>
>
> If I understand it correctly, the function will continue to loop until
> either the count == 3 or until correct_password_give = True,
> satisfying the two conditions of the assignment, which were to lock a
> user out after three failed password attempts and to print "Access
> Granted" and end the module if the correct password is given.  Am I
> understanding this correctly?
>
> Thanks!
>
> On Jul 1, 12:06 am, alex23 <wuwe... at gmail.com> wrote:
>> On Jul 1, 3:38 pm, "sato.ph... at gmail.com" <sato.ph... at gmail.com>
>> wrote:
>>
>>> I have been able to make the module quit after entering a password
>>> three times, but can't get it to quit right away after the correct  
>>> one
>>> is entered.
>>
>> Not with the code you pasted, you haven't. There's a missing colon on
>> line 7 & line 9 isn't indented properly. It's always best if we're
>> referring to the same source when trying to help with a problem.
>>
>> The problem you're having, though, has to do with the while loop and
>> the fact that it's only checking one condition: has the 'count'
>> counter been incremented to 3. What you need to do is _also_ check  
>> for
>> the success condition:
>>
>> is_confirmed = False
>> while count != 3 or is_confirmed:
>>   guess = raw_input("Enter your password: ")
>>   guess = str(guess)
>>   if guess != password:
>>     print "Access Denied"
>>     count = count + 1
>>   else:
>>     print "Password Confirmed"
>>     is_confirmed = True
>>
>> This also provides you with a nice boolean that shows whether or not
>> the password was confirmed, which may be useful for latter code.
>>
>> However, whenever you want to loop a set number of times, it's  
>> usually
>> better to use a 'for' loop instead:
>>
>> PASSWORD = 'qwerty'
>> MAXRETRY = 3
>> for attempt in xrange(MAXRETRY):
>>   guess = str(raw_input('Enter your password: '))
>>   is_complete = guess == PASSWORD
>>   if is_complete:
>>     print 'Password confirmed'
>>     break # this exits the for loop
>>   else:
>>     print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
>>
>> This saves you from the burden of creating, incrementing & testing
>> your own counter.
>>
>> If there's anything here that isn't clear, please don't hesitate to
>> ask.
>
> -- 
>



From bdesth.quelquechose at free.quelquepart.fr  Wed Jul  1 12:39:18 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 18:39:18 +0200
Subject: Getting input the scanf way
In-Reply-To: <mailman.2438.1246467374.8015.python-list@python.org>
References: <mailman.2438.1246467374.8015.python-list@python.org>
Message-ID: <4a4bacd3$0$296$426a74cc@news.free.fr>

Mr.SpOOn a ?crit :
> Hi,
> I need to do some kind of interactive command line program.
> 
> I mean: I run the program, it asks me for input, I type something and
> then I get the output or other questions.
> I'm not sure what is the right way to achieve this.

Simplest : use raw_input()
Friendlier (at least on *n*x platforms) : use readline.

HTH


From bdesth.quelquechose at free.quelquepart.fr  Wed Jul  1 12:43:44 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 18:43:44 +0200
Subject: Basic question from pure beginner
In-Reply-To: <mailman.2434.1246465610.8015.python-list@python.org>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
	<mailman.2434.1246465610.8015.python-list@python.org>
Message-ID: <4a4badde$0$10226$426a74cc@news.free.fr>

Charles Yeomans a ?crit :

<ot>Please don't top-post (not corrected)</ot>

> Let me offer a bit of editing.
> 
> First, using the condition count != 3 is perhaps risky.  A mistake or a 
> change in logic in the loop body might result in an infinite loop.  So 
> instead I suggest
> 
> while count < 3...
> 
> Second, I'd suggest storing the value 3 in a variable with a name that 
> describes it.

Pretty sensible suggestion, but then:

> MaxAttempts = 3

follow conventions instead :

MAX_ATTEMPS = 3


(snip)

> Finally, I'd remove correct_password_given from the loop test, and 
> replace it with a break statement when the correct password is entered.

Then using a while loop and manually incrementing a counter is a waste 
of time - using a for loop would be simplier and less error-prone.




From bdesth.quelquechose at free.quelquepart.fr  Wed Jul  1 12:45:26 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Wed, 01 Jul 2009 18:45:26 +0200
Subject: Basic question from pure beginner
In-Reply-To: <npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
	<mailman.2434.1246465610.8015.python-list@python.org>
	<npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>
Message-ID: <4a4bae44$0$10226$426a74cc@news.free.fr>

Scott David Daniels a ?crit :
(snip)

> And even simpler:
>     PASSWORD = "qwerty"
>     MAXRETRY = 3
>     for attempt in range(MAXRETRY):
>         if raw_input('Enter your password: ') == PASSWORD:
>             print 'Password confirmed'
>             break # this exits the for loop
>         print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
>     else:
>         # The else for a for statement is not executed for breaks,
>         # So indicates the end of testing without a match
>         raise SystemExit # Or whatever you'd rather do.

Which is probably the most pythonic implementation.


From cmpython at gmail.com  Wed Jul  1 13:24:27 2009
From: cmpython at gmail.com (Che M)
Date: Wed, 1 Jul 2009 10:24:27 -0700 (PDT)
Subject: Ubigraph vs Matplotlib (dynamic plotting, event handling)
References: <300620092320590209%shaibani@ymail.com>
Message-ID: <307b4075-ec5b-4d06-a638-c62f38307e7e@q11g2000yqi.googlegroups.com>

On Jun 30, 6:20?pm, Ala <shaib... at ymail.com> wrote:
> Hello everyone,
>
> I intend to use python for some network graph plotting, with event
> handling (clicking on network nodes, zooming in/out etc..) and so far I
> have come across two good candidates which are Matplotlib and Ubigraph.
>
> Did anyone have any experience with either of them for dynamic plotting
> (a slider bar on a Qt interface causing the graph to be replotted for
> each value for example), as well as event handling? (it seems on first
> notice that Ubigraph will have an upperhand on that), as well as event
> handling such as mouse clicks? (on this one Matplotlib has good
> documentation showing it does achieve that while I find ubigraph's
> documentation lacking, but I'd preffere to have the opinion of those
> who have used them before).
>
> Thank you.

I have used Matplotlib for both uses.  It has a built-in toolbar that
allows for changing the plot (zoom, pan, etc), and has good support
for point picking (clicking on a datapoint to do send an event).  You
could probably connect the QT slider to the zoom function without much
trouble, and Matplotlib is embeddable in QT GUIs.


From andrew at acooke.org  Wed Jul  1 13:42:06 2009
From: andrew at acooke.org (andrew cooke)
Date: Wed, 1 Jul 2009 13:42:06 -0400 (CLT)
Subject: Suppressing Implicit Chained Exceptions (Python 3.0)
Message-ID: <59a8ef2bf270d290bc5ef5ee98ceb717.squirrel@acooke.dyndns.org>


I have some (library) code where an exception is caught and, since the
underlying cause is rather obscure, a different exception is raised that
more clearly explains the issue to the caller.

However, when printed via format_exc(), this new exception still has the
old exception attached via the mechanism described at
http://www.python.org/dev/peps/pep-3134/ (this is Python 3.0).

Is there any simple way to stop this?  It's rather annoying and
misleading, as it exposes a lot of internal detail that the caller does
not understand or want.  This is marked as an "open issue" in the PEP
described above.

Thanks,
Andrew





From __peter__ at web.de  Wed Jul  1 13:44:56 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 01 Jul 2009 19:44:56 +0200
Subject: logging module and binary strings
References: <mailman.2429.1246465077.8015.python-list@python.org>
Message-ID: <h2g7ah$ngv$00$1@news.t-online.com>

Frank Aune wrote:

>>>> import logging
>>>> logging.basicConfig(level=logging.DEBUG)
>>>> x='\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>>> x
> '\xfe\x9f\xce\xc3\xa1\x00\xff\x01'

>>>> logging.info(x)
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>     stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xfe in position 10:
> ordinal not in range(128)
>>>> logging.info(x, extra={'encoding':'utf-8'})
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>     stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'utf8' codec can't decode byte 0xfe in position 10:
> unexpected code byte

> Is there any way to log the above value of x "properly" using the python
> logging module? By properly I mean logging the value displayed when
> entering just x in the python shell and pressing enter.

How about logging.info(repr(x))?

Peter




From Scott.Daniels at Acm.Org  Wed Jul  1 13:47:47 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 01 Jul 2009 10:47:47 -0700
Subject: Basic question from pure beginner
In-Reply-To: <mailman.2434.1246465610.8015.python-list@python.org>
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com>	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com>
	<mailman.2434.1246465610.8015.python-list@python.org>
Message-ID: <npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>

Charles Yeomans wrote:
> Let me offer a bit of editing....
> Finally, I'd remove correct_password_given from the loop test, and 
> replace it with a break statement when the correct password is entered.
> 
> password = "qwerty"
> correct_password_given = False
> attemptcount = 0
> MaxAttempts = 3
> while attemptcount < MaxAttempts:
>   guess = raw_input("Enter your password: ")
>   guess = str(guess)
>   if guess != password:
>       print "Access Denied"
>       attemptcount = attemptcount + 1
>   else:
>       print "Password Confirmed"
>       correct_password_given = True
>       break


And even simpler:
     PASSWORD = "qwerty"
     MAXRETRY = 3
     for attempt in range(MAXRETRY):
         if raw_input('Enter your password: ') == PASSWORD:
             print 'Password confirmed'
             break # this exits the for loop
         print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
     else:
         # The else for a for statement is not executed for breaks,
         # So indicates the end of testing without a match
         raise SystemExit # Or whatever you'd rather do.

--Scott David Daniels
Scott.Daniels at Acm.Org


From no.email at please.post  Wed Jul  1 13:56:55 2009
From: no.email at please.post (kj)
Date: Wed, 1 Jul 2009 17:56:55 +0000 (UTC)
Subject: Why re.match()?
Message-ID: <h2g817$mjo$1@reader1.panix.com>



For a recovering Perl-head like me it is difficult to understand
why Python's re module offers both match and search.  Why not just
use search with a beginning-of-string anchor?  I find it particularly
puzzling because I have this (possibly mistaken) idea that the
Python design philosophy tends towards minimalism, a sort of Occam's
razor, when it comes to language entities; i.e. having re.match
along with re.search seems to me like an "unnecessary multiplication
of entities".  What am I missing?

TIA!

kj


From timmyt at smarttypes.org  Wed Jul  1 13:58:33 2009
From: timmyt at smarttypes.org (timmyt)
Date: Wed, 1 Jul 2009 10:58:33 -0700 (PDT)
Subject: a little wsgi framework
Message-ID: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>

i'm interested in getting opinions on a small wsgi framework i
assembled from webob, sqlalchemy, genshi, and various code fragments i
found on the inter-tubes

here is the interesting glue - any comments / suggestions would be
much appreciated

------------------
the wsgi app
------------------
def application(environ, start_response):
    path = environ.get('PATH_INFO', '').lstrip('/')

    for regex, callback in urls:
        match = re.search(regex, path)

        if match:
            environ['myapp.url_args'] = match.groups()
            request = webob.Request(environ)

            try:
                return callback(request, start_response)
            except Exception, ex:
                start_response('500 Internal Server Error', [('Content-
Type', 'text/plain')])
                return [traceback.format_exc()]

    start_response('404 Not Found', [('Content-Type', 'text/plain')])
    return ["Couldn't find the URL specified."]


----------------------------------
the controller decorator
----------------------------------
def web_decorator(filename, method='html'):

    def decorator(target):

        def wrapper(request, start_response):

            #genshi TemplateLoader
            template = loader.load(filename)

            global config

            try:
                return_dict = target(request, start_response)
                return_string = template.generate(**return_dict).render
(method)
                config['database.Session'].commit()
            except:
                config['database.Session'].rollback()
                raise
            finally:
                config['database.Session'].remove()

            #TODO: alter 'Content-Type' per method being passed
            start_response('200 OK', [('Content-Type', 'text/html')])
            return [return_string]

        return wrapper

    return decorator


From lists at cheimes.de  Wed Jul  1 14:01:55 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 01 Jul 2009 20:01:55 +0200
Subject: A question about fill_free_list(void) function
In-Reply-To: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
Message-ID: <h2g8aj$tnb$1@ger.gmane.org>

Pedram schrieb:
> Hello community,
> I'm reading the CPython interpreter source code,
> first, if you have something that I should know for better reading
> this source code, I would much appreciate that :)
> second, in intobject.c file, I read the following code in
> fill_free_list function that I couldn't understand:
> <code>while (--q > p)
>     Py_TYPE(q) = (struct _typeobject *)(q-1);
> Py_TYPE(q) = NULL;
> </code>
> What does it mean?

The code is abusing the ob_type member to store a single linked, NULL
terminated list of free integer objects. It's a tricky optimization you
don't have to understand in order to understand the rest of the code.

And no, the code in ctypes.h is totally unrelated to the free list in
intobject.c.

Christian



From robert.kern at gmail.com  Wed Jul  1 14:33:53 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 01 Jul 2009 13:33:53 -0500
Subject: deleting certain entries in numpy array
In-Reply-To: <4a4b7763$1@news.fhg.de>
References: <4a4b7763$1@news.fhg.de>
Message-ID: <h2ga6h$3dt$1@ger.gmane.org>

On 2009-07-01 09:51, Sebastian Schabe wrote:
> Hello everybody,
>
> I'm new to python and numpy and have a little/special problem:

You will want to ask numpy questions on the numpy mailing list.

   http://www.scipy.org/Mailing_Lists

> I have an numpy array which is in fact a gray scale image mask, e.g.:
>
> mask =
> array([[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 255, 255, 255, 0, 0, 255, 0],
> [ 0, 0, 255, 255, 255, 0, 0, 255, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0],
> [ 0, 0, 0, 0, 0, 0, 0, 0, 0]], dtype=uint8)
>
> and I have another array of (y, x) positions in that mask (first two
> values of each row):
>
> pos =
> array([[ 3., 2., 0., 0.],
> [ 3., 4., 0., 0.],
> [ 5., 2., 0., 0.],
> [ 5., 4., 0., 0.],
> [ 6., 2., 0., 0.],
> [ 6., 7., 0., 0.],
> [ 0., 0., 0., 0.],
> [ 8., 8., 0., 0.]])
>
> and now I only want to keep all lines from 2nd array pos with those
> indices that are nonzero in the mask, i.e. line 3-6 (pos[2]-pos[5]).
>
> F.e. line 4 in pos has the values (5, 4) and mask[5][4] is nonzero, so I
> want to keep it. While line 2 (pos[1]) has the values (4, 6) and
> mask[4][6] is zero, so shall be discarded.
>
> I want to avoid a for loop (if possible!!!) cause I think (but don't
> know) numpy array are handled in another way. I think numpy.delete is
> the right function for discarding the values, but I don't know how to
> build the indices.

First, convert the pos array to integers, and just the columns with indices in them:

   ipos = pos[:,:2].astype(int)

Now check the values in the mask corresponding to these positions:

   mask_values = mask[ipos[:,0], ipos[:,1]]

Now extract the rows from the original pos array where mask_values is nonzero:

   result = pos[mask_values != 0]

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From backup95 at netcabo.pt  Wed Jul  1 14:45:26 2009
From: backup95 at netcabo.pt (=?UTF-8?B?Sm/Do28gVmFsdmVyZGU=?=)
Date: Wed, 01 Jul 2009 19:45:26 +0100
Subject: No trees in the stdlib?
In-Reply-To: <h2f7ba$njc$5@lust.ihug.co.nz>
References: <mailman.2139.1245994218.8015.python-list@python.org>	<h21mgt$oav$1@panix3.panix.com>	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
Message-ID: <4A4BAEC6.1060109@netcabo.pt>

Lawrence D'Oliveiro wrote:
> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o 
> Valverde wrote:
>
>   
>> Simple example usage case: Insert string into data structure in sorted
>> order if it doesn't exist, else retrieve it.
>>     
>
>     the_set = set( ... )
>
>     if str in the_set :
>         ... "retrieval" case ...
>     else :
>         the_set.add(str)
>     #end if
>
> Want sorted order?
>
>     sorted(tuple(the_set))
>
> What could be simpler?
>
>   

Try putting that inside a loop with thousands of iterations and you'll 
see what the problem is.


From duncan.booth at invalid.invalid  Wed Jul  1 14:52:34 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 1 Jul 2009 18:52:34 GMT
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
Message-ID: <Xns9C3BCA27ABC36duncanbooth@127.0.0.1>

kj <no.email at please.post> wrote:

> 
> 
> For a recovering Perl-head like me it is difficult to understand
> why Python's re module offers both match and search.  Why not just
> use search with a beginning-of-string anchor?  I find it particularly
> puzzling because I have this (possibly mistaken) idea that the
> Python design philosophy tends towards minimalism, a sort of Occam's
> razor, when it comes to language entities; i.e. having re.match
> along with re.search seems to me like an "unnecessary multiplication
> of entities".  What am I missing?
> 
RTFM?

http://docs.python.org/library/re.html#matching-vs-searching says:

> Note that match may differ from search even when using a regular
> expression beginning with '^': '^' matches only at the start of the
> string, or in MULTILINE mode also immediately following a newline. The
> ?match? operation succeeds only if the pattern matches at the start of
> the string regardless of mode, or at the starting position given by
> the optional pos argument regardless of whether a newline precedes
> it. 

So, for example:

>>> re.compile("c").match("abcdef", 2)
<_sre.SRE_Match object at 0x0000000002C09B90>
>>> re.compile("^c").search("abcdef", 2)
>>>

The ^ anchors you to the start of the string (or start of line in multiline 
mode) even if you specify a non-zero position. The match method just tells 
you if the pattern matches at the specified starting position regardless of 
whether it is the start of the string.



From damienlmoore at gmail.com  Wed Jul  1 15:30:51 2009
From: damienlmoore at gmail.com (spillz)
Date: Wed, 1 Jul 2009 12:30:51 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org>
Message-ID: <e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com>

On Jun 29, 3:15?pm, Pascal Chambon <chambon.pas... at gmail.com> wrote:
> Hello everyone
>
> I've had real issues with subprocesses recently : from a python script,
> on windows, I wanted to "give control" to a command line utility, i.e
> forward user in put to it and display its output on console. It seems
> simple, but I ran into walls :


If you are willing to have a wxPython dependency, wx.Execute handles
non-blocking i/o with processes on all supported platforms

more discussion of python's blocking i/o issues here:
http://groups.google.com/group/comp.lang.python/browse_thread/thread/a037349e18f99630/60886b8beb55cfbc?q=#60886b8beb55cfbc


From melissa at corsairsolutions.com  Wed Jul  1 15:57:35 2009
From: melissa at corsairsolutions.com (Melissa Powers)
Date: Wed, 1 Jul 2009 15:57:35 -0400
Subject: Python 2.5 incompatible with Fedora Core 6 - packaging problems
	again
Message-ID: <51BDF10DBC00564DBBBE62B537CF53922B9ADD@csi-svr1.csi.local>

Hi,

 

This may be a stretch but I came across this blog while searching for a
SW Packaging Engineer.  Do you know anyone in the Boston, MA area who
may be interested in this position?  The company is a start up with a
lot of funding and this is an opportunity to define the environment and
grow with a promising company.  Please4= forward to anyone you may know
of...

 

SW Packaging Engineer

*         Python developer

*         Red Hat Applications expert (Fedora 10) 

*         They want a real Red Hat Linux expert

*         Custom Build Distribution 

*         Custom RPM's 

*         Some Linux Server administration duties 

*         Virtualization experience a big plus

 

 

Melissa Frechette Powers

Account Manager

Corsair Solutions, Inc.

2 New Pasture Rd Unit 1

Newburyport, MA 01950

978-465-0085 x 206 Phone

978-465-0068 Fax

 

http://www.corsairsolutions.com <http://www.corsairsolutions.com> 

Please visit our NEW website: www.corsairsolutions.com
<http://www.corsairsolutions.com> 

 

The documents included with this electronic mail transmission contain
information from the staffing firm of Corsair Solutions, Inc which is
confidential and/or privileged. This information is intended to be for
the use of the addressee only. Note that any disclosure, printing,
photocopying, distribution or use of the contents of this e-mailed
information by persons other than the addressee or an agent of the
addressee, is unauthorized and prohibited. If you have received this
electronic mail in error, please notify us via electronic mail reply to
the sender or by telephone (collect 877-626-7724) immediately.

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/6e5070b4/attachment-0001.html>

From stef.mientki at gmail.com  Wed Jul  1 16:08:13 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Wed, 01 Jul 2009 22:08:13 +0200
Subject: Adding an object to the global namespace through " f_globals"  is
	that allowed ?
Message-ID: <4A4BC22D.70502@gmail.com>

hello,

I need to add an object's name to the global namespace.
The reason for this is to create an environment,
where you can add some kind of math environment,
where no need for Python knowledge is needed.

The next statement works,
but I'm not sure if it will have any dramatical side effects,
other than overruling a possible object with the name A

def some_function ( ...) :
      A = object ( ...)
      sys._getframe(1).f_globals [ Name ] = A


thanks,
Stef Mientki


From ben+python at benfinney.id.au  Wed Jul  1 16:16:43 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 02 Jul 2009 06:16:43 +1000
Subject: deleting certain entries in numpy array
References: <4a4b7763$1@news.fhg.de>
Message-ID: <87fxdgtaz8.fsf@benfinney.id.au>

Sebastian Schabe <sebastian.schabe at gmx.de> writes:

> I want to avoid a for loop (if possible!!!) cause I think (but don't
> know) numpy array are handled in another way.

Yes, Numpy arrays can be indexed logically by a boolean array.

> I think numpy.delete is the right function for discarding the values,
> but I don't know how to build the indices.

You don't need to discard the values. You can get a new array which is a
filtered version of an existing array, by using an array of bool values
as the index to the old array::

    >>> import numpy
    >>> mask = numpy.array([
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0, 255, 255, 255,   0,   0, 255,   0],
    ...     [  0,   0, 255, 255, 255,   0,   0, 255,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     [  0,   0,   0,   0,   0,   0,   0,   0,   0],
    ...     ], dtype=numpy.uint8)
    >>> mask > 0
    array([[False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False,  True,  True,  True, False, False,  True, False],
           [False, False,  True,  True,  True, False, False,  True, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False],
           [False, False, False, False, False, False, False, False, False]],
           dtype=bool)
    >>> mask[mask > 0]
    array([255, 255, 255, 255, 255, 255, 255, 255], dtype=uint8)

However, your case is somewhat more tricky: you need to construct the
boolean array based on coordinates from a separate array. That doesn't
require a for loop statement, but AFAICT it does require manually
generating the array of bools. I've done it with a list comprehension::

    >>> pos = numpy.array([
    ...     [  3.,   2.,   0.,   0.],
    ...     [  3.,   4.,   0.,   0.],
    ...     [  5.,   2.,   0.,   0.],
    ...     [  5.,   4.,   0.,   0.],
    ...     [  6.,   2.,   0.,   0.],
    ...     [  6.,   7.,   0.,   0.],
    ...     [  0.,   0.,   0.,   0.],
    ...     [  8.,   8.,   0.,   0.],
    ...     ])
    >>> pos[numpy.array(
    ...     [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]])]
    array([[ 5.,  2.,  0.,  0.],
           [ 5.,  4.,  0.,  0.],
           [ 6.,  2.,  0.,  0.],
           [ 6.,  7.,  0.,  0.]])

Here it is again, showing my working steps::

    >>> pos[:, 0:2]
    array([[ 3.,  2.],
           [ 3.,  4.],
           [ 5.,  2.],
           [ 5.,  4.],
           [ 6.,  2.],
           [ 6.,  7.],
           [ 0.,  0.],
           [ 8.,  8.]])
    >>> [(int(x), int(y)) for (x, y) in pos[:, 0:2]]
    [(3, 2), (3, 4), (5, 2), (5, 4), (6, 2), (6, 7), (0, 0), (8, 8)]
    >>> [mask[int(x), int(y)] for (x, y) in pos[:, 0:2]]
    [0, 0, 255, 255, 255, 255, 0, 0]
    >>> [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]]
    [False, False, True, True, True, True, False, False]
    >>> numpy.array(
    ...     [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]])
    array([False, False,  True,  True,  True,  True, False, False],
    dtype=bool)
    >>> pos[numpy.array(
    ...     [mask[int(x), int(y)] > 0 for (x, y) in pos[:, 0:2]])]
    array([[ 5.,  2.,  0.,  0.],
           [ 5.,  4.,  0.,  0.],
           [ 6.,  2.,  0.,  0.],
           [ 6.,  7.,  0.,  0.]])

-- 
 \                            ?Holy knit one purl two, Batman!? ?Robin |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From Digvijoy.C at gmail.com  Wed Jul  1 16:20:03 2009
From: Digvijoy.C at gmail.com (digz)
Date: Wed, 1 Jul 2009 13:20:03 -0700 (PDT)
Subject: problems displaying results in ibm_db
Message-ID: <c59882af-be7e-4212-8020-8a3984e5fa5f@k8g2000yqn.googlegroups.com>

This simple db connectivity and select test program works in the
interactive mode

>>> import ibm_db
>>> conn = ibm_db.connect( 'DATABASE', 'user', 'passwd')
>>> result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST 1 ROWS ONLY')
>>> row = ibm_db.fetch_tuple( result )
>>> for r in row:
...    print r
...
13
ABC
4
2009-05-11

The same executed from a script using python testdb.py does not yield
anything , What am I doing wrong ?

import ibm_db
conn = ibm_db.connect( 'DATABASE', 'user', 'pwd')
result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST
1 ROWS ONLY')
row = ibm_db.fetch_tuple( result )
for r in row:
      print r

==
>python testdb.py
database value after unicode conversion is : N
database value sent to CLI is : N
>
==


From psimon at sonic.net  Wed Jul  1 17:16:18 2009
From: psimon at sonic.net (Paul Simon)
Date: Wed, 1 Jul 2009 14:16:18 -0700
Subject: problem installing python 2.6.2 from tarball
Message-ID: <4a4bd226$0$95520$742ec2ed@news.sonic.net>

I have just finished going through the usual ./configure, make, etc. and now 
have a load of stuff in my home directory that I think doesn't belong there. 
Apparently I did the installation from my home directory (linux) and have a 
directory  in my home directory "Python2.6.2" with subdirectories like 
"build", "Demo", "Doc", "Include", "Lib", etc.  There are many files under 
/usr/bin/local/  which appear to be duplicates.

This looks like a mess to me and would like some help to sort this out.

Paul Simon 




From Mariosky at gmail.com  Wed Jul  1 17:34:51 2009
From: Mariosky at gmail.com (Mario Garcia)
Date: Wed, 1 Jul 2009 14:34:51 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method returns 
	items in order
Message-ID: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>

Im trying to use sets for doing statistics from a data set.
I want to select, 70% random records from a List. I thougth set where
a good idea so I
tested this way:

c = set(range(1000))
for d in range(1000):
     print c.pop()

I was hoping to see a print out of random selected numbers from 1 to
1000
but I got an ordered count from 1 to 1000.
I also tried using a dictionary, with keys from 1 to 10, and also got
the keys in order.

Im using:
 Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug  4 2008, 13:45:20)
 [GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin

Examples in the documentation seem to work. But I cant make it.
Can some one, give me a hint on whats going on?




From lance.ellinghaus at hp.com  Wed Jul  1 18:02:49 2009
From: lance.ellinghaus at hp.com (ELLINGHAUS, LANCE)
Date: Wed, 1 Jul 2009 22:02:49 +0000
Subject: Using Python to set desktop background image under Windows XP
In-Reply-To: <h2f7jt$j33$1@south.jnrs.ja.net>
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
Message-ID: <197A4D1DF629F64A9260E3B454A218D13403C48D2E@GVW1158EXB.americas.hpqcorp.net>

Does anyone have any code that would allow setting the desktop background image under Windows XP?

Thank you,
lance


Lance Ellinghaus
mailto:lance.ellinghaus at hp.com


From skip at pobox.com  Wed Jul  1 18:07:16 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 1 Jul 2009 17:07:16 -0500
Subject: Timeout when connecting to sybase DBS
In-Reply-To: <794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
Message-ID: <19019.56852.751152.510037@montanaro.dyndns.org>

    Gil> Are you saying, that when you trying to connect to a sybase DBS
    Gil> server and the DBS or the server is down, you get an error after a
    Gil> few seconds and not after a few minutes?

Yes, though thankfully our server tends to almost always be up.

    Gil> Which python version are you using?

We're still running 2.4.5 at work and have a slightly hacked very old
version of the python-sybase package (0.36).

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    when i wake up with a heart rate below 40, i head right for the espresso
    machine. -- chaos @ forums.usms.org


From rhodri at wildebst.demon.co.uk  Wed Jul  1 18:08:33 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 01 Jul 2009 23:08:33 +0100
Subject: Python/Pygame question
In-Reply-To: <cab5c962-5833-4d4f-89dc-c1475c8076bf@j32g2000yqh.googlegroups.com>
References: <cab5c962-5833-4d4f-89dc-c1475c8076bf@j32g2000yqh.googlegroups.com>
Message-ID: <op.uwes4jnja8ncjz@gnudebst>

On Tue, 30 Jun 2009 19:15:24 +0100, Crip <cripplemeal at gmail.com> wrote:

> I have been experimenting with pygame. I would like to know how to go
> about placing an image of my creation as the background of the
> generated window. To where should I save the image, and what should it
> be saved as?

Wherever will be most useful to you (the same directory as where you
are developing your game is often good).  You can use most of the common
formats, so pick whatever's most appropriate for your image.

The documentation is at http://www.pygame.org/docs/ref/image.html
In particular, you use pygame.image.load() to load your file into a
surface, then blit it into your display.  Some resizing may be
necessary!


-- 
Rhodri James *-* Wildebeest Herder to the Masses


From skip at pobox.com  Wed Jul  1 18:08:57 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 1 Jul 2009 17:08:57 -0500
Subject: Timeout when connecting to sybase DBS
In-Reply-To: <5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com>
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
	<5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com>
Message-ID: <19019.56953.762133.210100@montanaro.dyndns.org>

    Gil> There's no such group as python-sybase :-(

http://sourceforge.net/mailarchive/forum.php?forum_name=python-sybase-misc

S


From clp2 at rebertia.com  Wed Jul  1 18:11:45 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 1 Jul 2009 15:11:45 -0700
Subject: Noob
In-Reply-To: <d152d3690906301102j63d1bd74uc90cd0a56144d2fe@mail.gmail.com>
References: <d152d3690906301102j63d1bd74uc90cd0a56144d2fe@mail.gmail.com>
Message-ID: <50697b2c0907011511r6aac78d9m3f190c19b79ed832@mail.gmail.com>

On Tue, Jun 30, 2009 at 11:02 AM, kaffeen<kaffeen at gmail.com> wrote:
> Hello all, just joined this list and am just beginning to learn Python.
> Thanks to everyone for making this a great place to learn and their
> contributions.
>
> As mentioned, I'm new to Python (but have experience with other programming
> languages/scripting). I have a couple of questions...
<snip>
> 2) What are the differences between IPython and IDLE, is one better than the
> other, why?

IDLE is a GUI interactive interpreter and IDE that uses the Tk GUI toolkit.
IPython is a command-line interactive interpreter with tab-completion,
advanced command history functions, and other handy extras.

I would say they have completely different purposes. IPython is a
souped-up version of the command-line Python REPL, but doesn't include
a text editor for writing a file of code. It is very good for
experimenting and exploring with though. IDLE is a quite servicable
free IDE.

Cheers,
Chris
-- 
http://blog.rebertia.com


From pavlovevidence at gmail.com  Wed Jul  1 18:28:10 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 15:28:10 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>

On Jul 1, 2:34?pm, Mario Garcia <Mario... at gmail.com> wrote:
> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I
> tested this way:
>
> c = set(range(1000))
> for d in range(1000):
> ? ? ?print c.pop()
>
> I was hoping to see a print out of random selected numbers from 1 to
> 1000
> but I got an ordered count from 1 to 1000.
> I also tried using a dictionary, with keys from 1 to 10, and also got
> the keys in order.
>
> Im using:
> ?Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug ?4 2008, 13:45:20)
> ?[GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin
>
> Examples in the documentation seem to work. But I cant make it.
> Can some one, give me a hint on whats going on?

The keys in a dict or set are not in random order, but (more or less)
they are in hash key order modulo the size of the hash.  This neglects
the effect of hash collisions.  The hash code of an integer happens to
the integer itself, so oftentimes a dict or set storing a sequence of
integers will end up with keys in order, although it's not guaranteed
to be so.

Point it, it's unsafe to rely on *any* ordering behavior in a dict or
set, even relatively random order.

Instead, call random.shuffle() on the list, and iterate through that
to get the elements in random order.


Carl Banks


From mensanator at aol.com  Wed Jul  1 18:29:19 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 1 Jul 2009 15:29:19 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <51a36108-d3dc-4a03-9a85-84a5da9b541a@l31g2000yqb.googlegroups.com>

On Jul 1, 4:34?pm, Mario Garcia <Mario... at gmail.com> wrote:
> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I
> tested this way:
>
> c = set(range(1000))
> for d in range(1000):
> ? ? ?print c.pop()
>
> I was hoping to see a print out of random selected numbers from 1 to
> 1000
> but I got an ordered count from 1 to 1000.
> I also tried using a dictionary, with keys from 1 to 10, and also got
> the keys in order.
>
> Im using:
> ?Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug ?4 2008, 13:45:20)
> ?[GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin
>
> Examples in the documentation seem to work. But I cant make it.
> Can some one, give me a hint on whats going on?

Sets don't help. Try this:

>>> import random

>>> c = range(100)
>>> c
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

>>> random.shuffle(c)
>>> c
[78, 62, 38, 54, 12, 48, 24, 20, 8, 14, 1, 69, 49, 92, 41, 64, 17, 35,
88, 40, 73, 45, 5, 84, 96, 90, 98, 57, 51, 75, 99, 13, 29, 4, 97, 77,
74, 56, 91, 95, 59, 79, 89, 19, 9, 42, 31, 85, 86, 23, 27, 50, 6, 21,
15, 80, 3, 30, 87, 82, 16, 63, 2, 55, 37, 33, 10, 61, 93, 72, 60, 67,
44, 65, 11, 70, 52, 58, 47, 18, 36, 66, 94, 28, 22, 68, 32, 76, 53,
25, 83, 34, 26, 71, 39, 43, 7, 46, 0, 81]

>>> for d in c:
	print c.pop(),

81 0 46 7 43 39 71 26 34 83 25 53 76 32 68 22 28 94 66 36 18 47 58 52
70 11 65 44 67 60 72 93 61 10 33 37 55 2 63 16 82 87 30 3 80 15 21 6
50 27

Notice that the numbers are coming out in the exact reverse order
of the list, because you used .pop() without an index number.
But it's ok in _THIS_ example, because the list was randomly
shuffled before popping.


From pavlovevidence at gmail.com  Wed Jul  1 18:33:01 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 15:33:01 -0700 (PDT)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
Message-ID: <86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>

On Jul 1, 10:56?am, kj <no.em... at please.post> wrote:
> For a recovering Perl-head like me it is difficult to understand
> why Python's re module offers both match and search. ?Why not just
> use search with a beginning-of-string anchor? ?I find it particularly
> puzzling because I have this (possibly mistaken) idea that the
> Python design philosophy tends towards minimalism, a sort of Occam's
> razor, when it comes to language entities; i.e. having re.match
> along with re.search seems to me like an "unnecessary multiplication
> of entities". ?What am I missing?

It always seemed redundant to me also (notwithstanding Duncan Booth's
explanation of slight semantic differences).  However, I find myself
using re.match much more often than re.search, so perhaps in this case
a "second obvious way" is justified.


Carl Banks


From aahz at pythoncraft.com  Wed Jul  1 18:39:55 2009
From: aahz at pythoncraft.com (Aahz)
Date: 1 Jul 2009 15:39:55 -0700
Subject: Problem with uuid package when embedding a python interpreter
References: <7d5cfbf0-38d5-4505-a93a-f321d0da74b8@c36g2000yqn.googlegroups.com>
Message-ID: <h2gojr$e1u$1@panix3.panix.com>

In article <7d5cfbf0-38d5-4505-a93a-f321d0da74b8 at c36g2000yqn.googlegroups.com>,
=?ISO-8859-1?Q?J=E9r=F4me_Fuselier?=  <jerome.fuselier at gmail.com> wrote:
>
>I've tried to import a script in an embedded python intrepreter but
>this script fails when it imports the uuid module. I have a
>segmentation fault in Py_Finalize().

You may want to also ask on the capi-sig mailing list.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From mensanator at aol.com  Wed Jul  1 18:47:08 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 1 Jul 2009 15:47:08 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<51a36108-d3dc-4a03-9a85-84a5da9b541a@l31g2000yqb.googlegroups.com>
Message-ID: <6891d82f-9dc3-4f43-8490-c339edf85ad8@p23g2000vbl.googlegroups.com>

On Jul 1, 5:29?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 1, 4:34?pm, Mario Garcia <Mario... at gmail.com> wrote:
>
>
>
>
>
> > Im trying to use sets for doing statistics from a data set.
> > I want to select, 70% random records from a List. I thougth set where
> > a good idea so I
> > tested this way:
>
> > c = set(range(1000))
> > for d in range(1000):
> > ? ? ?print c.pop()
>
> > I was hoping to see a print out of random selected numbers from 1 to
> > 1000
> > but I got an ordered count from 1 to 1000.
> > I also tried using a dictionary, with keys from 1 to 10, and also got
> > the keys in order.
>
> > Im using:
> > ?Python 2.5.2 |EPD 2.5.2001| (r252:60911, Aug ?4 2008, 13:45:20)
> > ?[GCC 4.0.1 (Apple Computer, Inc. build 5370)] on darwin
>
> > Examples in the documentation seem to work. But I cant make it.
> > Can some one, give me a hint on whats going on?
>
> Sets don't help. Try this:
>
> >>> import random
> >>> c = range(100)
> >>> c
>
> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
> 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
> 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
> 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
> 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
> 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]
>
> >>> random.shuffle(c)
> >>> c
>
> [78, 62, 38, 54, 12, 48, 24, 20, 8, 14, 1, 69, 49, 92, 41, 64, 17, 35,
> 88, 40, 73, 45, 5, 84, 96, 90, 98, 57, 51, 75, 99, 13, 29, 4, 97, 77,
> 74, 56, 91, 95, 59, 79, 89, 19, 9, 42, 31, 85, 86, 23, 27, 50, 6, 21,
> 15, 80, 3, 30, 87, 82, 16, 63, 2, 55, 37, 33, 10, 61, 93, 72, 60, 67,
> 44, 65, 11, 70, 52, 58, 47, 18, 36, 66, 94, 28, 22, 68, 32, 76, 53,
> 25, 83, 34, 26, 71, 39, 43, 7, 46, 0, 81]
>
> >>> for d in c:

Oops! You don't want to iterate through c while popping it.
Your original for statement is what to use.

>
> ? ? ? ? print c.pop(),
>
> 81 0 46 7 43 39 71 26 34 83 25 53 76 32 68 22 28 94 66 36 18 47 58 52
> 70 11 65 44 67 60 72 93 61 10 33 37 55 2 63 16 82 87 30 3 80 15 21 6
> 50 27
>
> Notice that the numbers are coming out in the exact reverse order
> of the list, because you used .pop() without an index number.
> But it's ok in _THIS_ example, because the list was randomly
> shuffled before popping.


From ben+python at benfinney.id.au  Wed Jul  1 19:01:10 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 02 Jul 2009 09:01:10 +1000
Subject: Trying to use sets for random selection,
	but the pop() method returns  items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <87bpo4t3d5.fsf@benfinney.id.au>

Mario Garcia <Mariosky at gmail.com> writes:

> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I
> tested this way:
> 
> c = set(range(1000))
> for d in range(1000):
>      print c.pop()
> 
> I was hoping to see a print out of random selected numbers from 1 to
> 1000

The ?set? and ?dict? types are unordered collections, but that doesn't
have any implication of randomness. Rather, it means that the order of
retrieval is not guaranteed to be predictable.

You can't even predict that it'll be a random order; you can't predict
(based on the Python code) *anything* about the order. Any appearance of
predictable ordering is an unreliable artefact of the implementation and
may change at any time, since the language explicitly disclaims any
specific ordering to the items.

For a random sequence, you want the ?random? module
<URL:http://docs.python.org/library/random>::

    >>> import random
    >>> for n in (random.randint(0, 999) for _ in range(10)):
    ...     print n
    ...
    381
    4
    471
    624
    70
    979
    110
    932
    105
    262 

-- 
 \        ?When in doubt tell the truth. It will confound your enemies |
  `\   and astound your friends.? ?Mark Twain, _Following the Equator_ |
_o__)                                                                  |
Ben Finney


From alex.lavoro.propio at gmail.com  Wed Jul  1 19:18:13 2009
From: alex.lavoro.propio at gmail.com (Alex)
Date: Wed, 1 Jul 2009 16:18:13 -0700 (PDT)
Subject: Open Source RSS Reader in Python?
Message-ID: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>

I am looking for an open source RSS reader (desktop, not online)
written in Python but in vain. I am not looking for a package but a
fully functional software.

Google: python "open source" (rss OR feeds) reader

Any clue ?


From tn.pablo at gmail.com  Wed Jul  1 19:26:36 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Wed, 1 Jul 2009 18:26:36 -0500
Subject: problem installing python 2.6.2 from tarball
In-Reply-To: <4a4bd226$0$95520$742ec2ed@news.sonic.net>
References: <4a4bd226$0$95520$742ec2ed@news.sonic.net>
Message-ID: <fdd00b510907011626u3bb9e652nc116843560d573ee@mail.gmail.com>

On Wed, Jul 1, 2009 at 16:16, Paul Simon<psimon at sonic.net> wrote:
> I have just finished going through the usual ./configure, make, etc. and now
> have a load of stuff in my home directory that I think doesn't belong there.
> Apparently I did the installation from my home directory (linux) and have a
> directory ?in my home directory "Python2.6.2" with subdirectories like
> "build", "Demo", "Doc", "Include", "Lib", etc. ?There are many files under
> /usr/bin/local/ ?which appear to be duplicates.
>
> This looks like a mess to me and would like some help to sort this out.
>
> Paul Simon

Sounds like you untarred directly into your home dir.  You're OK if
you delete those, they are the sources, although you should do so only
after uninstalling, just in case.
To unistall, follow this thread from the list from a while ago:
http://mail.python.org/pipermail/python-list/2004-December/296269.html
I have followed it and it worked.

Pablo Torres N.


From tn.pablo at gmail.com  Wed Jul  1 19:34:18 2009
From: tn.pablo at gmail.com (ptn)
Date: Wed, 1 Jul 2009 16:34:18 -0700 (PDT)
Subject: problems displaying results in ibm_db
References: <c59882af-be7e-4212-8020-8a3984e5fa5f@k8g2000yqn.googlegroups.com>
Message-ID: <052ecdf2-6253-4885-9f16-2f24062f1f07@g6g2000vbr.googlegroups.com>

On Jul 1, 3:20?pm, digz <Digvijo... at gmail.com> wrote:
> result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST
> 1 ROWS ONLY')

You have the same string split into two lines, which means that what
you actually have is this:

result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH
FIRST<NEWLINE CHARACTER HERE>
1 ROWS ONLY')

You need to escape that little '\n' with a backslash:

result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST\
1 ROWS ONLY')

Better yet, use implicit string concatenation:

result = ibm_db.exec_immediate( conn, 'SELECT * FROM TEST FETCH FIRST'
'1 ROWS ONLY')

Note that now you have two strings: 'SELECT * FROM TEST FETCH FIRST'
and  '1 ROWS ONLY'


Pablo Torres N.


From tn.pablo at gmail.com  Wed Jul  1 19:36:38 2009
From: tn.pablo at gmail.com (ptn)
Date: Wed, 1 Jul 2009 16:36:38 -0700 (PDT)
Subject: problem installing python 2.6.2 from tarball
References: <4a4bd226$0$95520$742ec2ed@news.sonic.net>
Message-ID: <9286d6b5-91bf-4a74-99ba-c7c90329d4aa@f33g2000vbm.googlegroups.com>

Sounds like you untarred directly into your home dir.  You're OK if
you delete those, they are the sources, although you should do so only
after uninstalling, just in case.

To unistall, follow this thread from the list from a while ago:
http://mail.python.org/pipermail/python-list/2004-December/296269.html

I have followed it and it worked.


From sajmikins at gmail.com  Wed Jul  1 19:39:31 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Wed, 1 Jul 2009 16:39:31 -0700 (PDT)
Subject: Open Source RSS Reader in Python?
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <cca5f130-2e9a-40d7-a6ad-c580f7daffb8@z28g2000vbl.googlegroups.com>

On Jul 1, 7:18?pm, Alex <alex.lavoro.pro... at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?

There's Canto: http://codezen.org/canto/


From python at mrabarnett.plus.com  Wed Jul  1 19:50:16 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 00:50:16 +0100
Subject: Why re.match()?
In-Reply-To: <86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>
Message-ID: <4A4BF638.5060500@mrabarnett.plus.com>

Carl Banks wrote:
> On Jul 1, 10:56 am, kj <no.em... at please.post> wrote:
>> For a recovering Perl-head like me it is difficult to understand
>> why Python's re module offers both match and search.  Why not just
>> use search with a beginning-of-string anchor?  I find it particularly
>> puzzling because I have this (possibly mistaken) idea that the
>> Python design philosophy tends towards minimalism, a sort of Occam's
>> razor, when it comes to language entities; i.e. having re.match
>> along with re.search seems to me like an "unnecessary multiplication
>> of entities".  What am I missing?
> 
> It always seemed redundant to me also (notwithstanding Duncan Booth's
> explanation of slight semantic differences).  However, I find myself
> using re.match much more often than re.search, so perhaps in this case
> a "second obvious way" is justified.
> 
re.match is anchored at a certain position, whereas re.search isn't. The
re module doesn't support Perl's \G anchor.


From robert.kern at gmail.com  Wed Jul  1 19:51:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 01 Jul 2009 18:51:31 -0500
Subject: logging module and binary strings
In-Reply-To: <200907011702.21450.Frank.Aune@broadpark.no>
References: <200907011702.21450.Frank.Aune@broadpark.no>
Message-ID: <h2gsq3$o8c$1@ger.gmane.org>

On 2009-07-01 10:02, Frank Aune wrote:
> Hello,
>
> ---- snip ----
>>>> import logging
>>>> logging.basicConfig(level=logging.DEBUG)
>>>> x='\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>>> x
> '\xfe\x9f\xce\xc3\xa1\x00\xff\x01'
>>>> print x
> ?????
>>>> logging.info(x)
> Traceback (most recent call last):
>    File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>      stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xfe in position 10:
> ordinal not in range(128)
>>>> logging.info(x, extra={'encoding':'utf-8'})
> Traceback (most recent call last):
>    File "/usr/lib/python2.6/logging/__init__.py", line 773, in emit
>      stream.write(fs % msg.encode("UTF-8"))
> UnicodeDecodeError: 'utf8' codec can't decode byte 0xfe in position 10:
> unexpected code byte
>
> ---- snip ----
>
> Is there any way to log the above value of x "properly" using the python
> logging module? By properly I mean logging the value displayed when entering
> just x in the python shell and pressing enter.

logging.info(repr(x))

Or, to be more descriptive in your logging message:

logging.info("Got a binary value: %r", x)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From benjamin at python.org  Wed Jul  1 19:55:23 2009
From: benjamin at python.org (Benjamin Peterson)
Date: Wed, 1 Jul 2009 23:55:23 +0000 (UTC)
Subject: getting rid of  =?utf-8?b?4oCU?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
Message-ID: <loom.20090701T235446-25@post.gmane.org>

someone <petshmidt <at> googlemail.com> writes:

> 
> Hello,
> 
> how can I replace '?' sign from string? Or do split at that character?
> Getting unicode error if I try to do it:
> 
> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> 1: ordinal not in range(128)


Please paste your code. I suspect that you are mixing unicode and normal strings.






From python at mrabarnett.plus.com  Wed Jul  1 19:56:22 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 00:56:22 +0100
Subject: getting rid of  =?windows-1252?Q?=97?=
In-Reply-To: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
Message-ID: <4A4BF7A6.9010500@mrabarnett.plus.com>

someone wrote:
> Hello,
> 
> how can I replace '?' sign from string? Or do split at that character?
> Getting unicode error if I try to do it:
> 
> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> 1: ordinal not in range(128)
> 
> 
> Thanks, Pet
> 
> script is # -*- coding: UTF-8 -*-

It sounds like you're mixing bytestrings with Unicode strings. I can't
be any more helpful because you haven't shown the code.


From python at mrabarnett.plus.com  Wed Jul  1 20:26:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 01:26:09 +0100
Subject: Getting input the scanf way
In-Reply-To: <8f67b6f80907010133t7f6e2d9eg9ffa3b927d540728@mail.gmail.com>
References: <8f67b6f80907010133t7f6e2d9eg9ffa3b927d540728@mail.gmail.com>
Message-ID: <4A4BFEA1.6020301@mrabarnett.plus.com>

Mr.SpOOn wrote:
> Hi,
> I need to do some kind of interactive command line program.
> 
> I mean: I run the program, it asks me for input, I type something and
> then I get the output or other questions.
> I'm not sure what is the right way to achieve this.
> 
Use raw_input() and print.


From benjamin.kaplan at case.edu  Wed Jul  1 20:27:33 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Wed, 1 Jul 2009 20:27:33 -0400
Subject: What are the limitations of cStringIO.StringIO() ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
Message-ID: <ec96e1390907011727p4cf7ca12y2d4739d6b46c3d4@mail.gmail.com>

On Wed, Jul 1, 2009 at 7:48 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
> Hi,
>
> I think I'm up against a limitation in cStringIO.StringIO(), but could not
> find any clues on the web, especially not in
> http://docs.python.org/library/stringio.html.
>
> What I have is the following function:
>
> ??? def concatenate_files(self,filename_array):
> ??????? import types
>
> ??????? f = cStringIO.StringIO()
> ??????? for filename in filename_array:
> ??????????? log_stream = LogStream(filename)
> ??????????? if not isinstance(log_stream, types.NoneType):
> ??????????????? try:
> ??????????????????? string_ = log_stream.input_file.read()
> ??????????????? except AttributeError, e:
> ??????????????????????? sys.stderr.write("AttributeError: "+str(e)+"\n")
> ??????????????????????? sys.stderr.write("log_stream:
> "+str(log_stream)+"\n")
> ??????????? else:
> ??????????????? return(None)
>
> ??????????? f.write(string_)
> ??????? return (f)
>
> And, when the list of files?- in filename_array - is pointing to long/large
> enough files, I get the exception:
>
> Traceback (most recent call last):
> ? File "svm_ts_tool_in_progress.py", line 244, in OnSelectCell
> ??? self.InspectorViewController(row,col)
> ? File "svm_ts_tool_in_progress.py", line 1216, in InspectorViewController
> ??? self.InspectorePaneGetRecords(self.req_table, rec)
> ? File "svm_ts_tool_in_progress.py", line 1315, in InspectorePaneGetRecords
> ??? log_stream =
> ConcatenatedLogStream(self.events_dict[req_table]["db_dict"].keys())
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 31, in
> __init__
> ??? self.input_file = self.concatenate_files(filename_array)
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 47, in
> concatenate_files
> ??? string_ = log_stream.input_file.read()
> MemoryError
>
> Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
> Could you suggest a better way to create a string that contains the
> concatenation of several big files ?
>

MemoryErrors are caused because, for whatever reason, the OS won't
allocate any more memory for the process. For a 32-bit Windows
process, that maximum is 2 GB. No matter what programming language or
library you use, you can't bypass that limit. There is a way to up the
limit to 3GB but I don't know how to do it. The link below has all the
information about Windows memory limits. If you need lots of really
big strings in memory simultaneously, you'll have to get a 64-bit
system with a ton of RAM.

http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx

> Thanks,
> Ron.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>


From missive at hotmail.com  Wed Jul  1 20:37:40 2009
From: missive at hotmail.com (Lee Harr)
Date: Thu, 2 Jul 2009 05:07:40 +0430
Subject: [ANNC] acromania-0.4
Message-ID: <SNT106-W41BF4D34D308A35248291CB12F0@phx.gbl>


Acromania is a word game of acronyms.

This program is a computer moderator for networked
games of acromania. It can connect to a channel on
IRC, or start a standalone server which can be
accessed much like a MUD.

http://acromania.googlecode.com/


Acromania uses Twisted and SQLite. Optionally, it can
use NLTK to generate computer opponents.

Acromania is released under GPLv3.


Changes in acromania-0.4:
    - autocreate conf.py on first start
    - initialize database on first start
    - add contact information
    - various bug fixes


Notes:
    I have only played the game using the standalone
    server on a secure network. If you have experience
    with programming IRC bots securely, please take
    a look and contact me if you see any problems.

    If you decide to connect it to IRC, please let me
    know, because I'd like to play :o)


_________________________________________________________________
Drag n? drop?Get easy photo sharing with Windows Live? Photos.

http://www.microsoft.com/windows/windowslive/products/photos.aspx


From http  Wed Jul  1 20:48:46 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 17:48:46 -0700
Subject: Trying to use sets for random selection,
	but the pop() method returns  items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <7xhbxvgb9t.fsf@ruckus.brouhaha.com>

Mario Garcia <Mariosky at gmail.com> writes:
> Im trying to use sets for doing statistics from a data set.
> I want to select, 70% random records from a List. I thougth set where
> a good idea so I

No that's not a good idea.  When the set/dict documentation says you
get the keys in an undetermined order, it doesn't mean the ordering is
random.  It means there is a fixed ordering controlled by the
implementation and not by you.

If you want a random sample, use random.sample().  See the docs for
the random module.


From http  Wed Jul  1 20:49:21 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 17:49:21 -0700
Subject: Trying to use sets for random selection,
	but the pop() method  returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
Message-ID: <7xd48jgb8u.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> Instead, call random.shuffle() on the list, and iterate through that
> to get the elements in random order.

It's better to use random.sample() than random.shuffle().


From sjmachin at lexicon.net  Wed Jul  1 21:20:29 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 1 Jul 2009 18:20:29 -0700 (PDT)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<86cabd92-f41f-4666-a6e6-3bfc4fda41ea@g19g2000yql.googlegroups.com>
	<mailman.2448.1246492219.8015.python-list@python.org>
Message-ID: <f4f1e9c1-c658-4ade-b80f-ec2bad1f2143@r33g2000yqn.googlegroups.com>

On Jul 2, 9:50?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Carl Banks wrote:
> > On Jul 1, 10:56 am, kj <no.em... at please.post> wrote:
> >> For a recovering Perl-head like me it is difficult to understand
> >> why Python's re module offers both match and search. ?Why not just
> >> use search with a beginning-of-string anchor? ?I find it particularly
> >> puzzling because I have this (possibly mistaken) idea that the
> >> Python design philosophy tends towards minimalism, a sort of Occam's
> >> razor, when it comes to language entities; i.e. having re.match
> >> along with re.search seems to me like an "unnecessary multiplication
> >> of entities". ?What am I missing?
>
> > It always seemed redundant to me also (notwithstanding Duncan Booth's
> > explanation of slight semantic differences). ?However, I find myself
> > using re.match much more often than re.search, so perhaps in this case
> > a "second obvious way" is justified.
>
> re.match is anchored at a certain position, whereas re.search isn't. The
> re module doesn't support Perl's \G anchor.

re.search is obstinately determined when it comes to flogging dead
horses:

C:\junk>\python26\python -mtimeit -s"import re" "re.match('xxx',
'y'*100)"
100000 loops, best of 3: 3.37 usec per loop

C:\junk>\python26\python -mtimeit -s"import re" "re.search('^xxx',
'y'*100)"
100000 loops, best of 3: 7.01 usec per loop

C:\junk>\python26\python -mtimeit -s"import re" "re.match('xxx',
'y'*1000)"
100000 loops, best of 3: 3.85 usec per loop

C:\junk>\python26\python -mtimeit -s"import re" "re.search('^xxx',
'y'*1000)"
10000 loops, best of 3: 37.9 usec per loop

C:\junk>


From magawake at gmail.com  Wed Jul  1 21:28:12 2009
From: magawake at gmail.com (Mag Gam)
Date: Wed, 1 Jul 2009 21:28:12 -0400
Subject: Multi thread reading a file
In-Reply-To: <h2eqv3$gpt$4@lust.ihug.co.nz>
References: <mailman.2420.1246413152.8015.python-list@python.org>
	<h2eqv3$gpt$4@lust.ihug.co.nz>
Message-ID: <1cbd6f830907011828i789e1f6fk18ce71da7290f6ee@mail.gmail.com>

LOL! :-)

Why not. I think I will take just do it single thread for now and if
performance is really that bad I can re investigate.

Either way, thanks everyone for your feedback! I think I like python a
lot because of the great user community and wiliness to help!



On Wed, Jul 1, 2009 at 1:07 AM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> In message <mailman.2420.1246413152.8015.python-list at python.org>, Mag Gam
> wrote:
>
>> I am very new to python and I am in the process of loading a very
>> large compressed csv file into another format. ?I was wondering if I
>> can do this in a multi thread approach.
>
> Why bother?
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul  1 21:28:19 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 02 Jul 2009 01:28:19 GMT
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
Message-ID: <pan.2009.07.02.01.28.18@REMOVE.THIS.cybersource.com.au>

On Wed, 01 Jul 2009 17:49:21 -0700, Paul Rubin wrote:

> Carl Banks <pavlovevidence at gmail.com> writes:
>> Instead, call random.shuffle() on the list, and iterate through that to
>> get the elements in random order.
> 
> It's better to use random.sample() than random.shuffle().

Why?


-- 
Steven


From pavlovevidence at gmail.com  Wed Jul  1 21:29:21 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 18:29:21 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com> 
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
Message-ID: <00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>

On Jul 1, 5:49?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > Instead, call random.shuffle() on the list, and iterate through that
> > to get the elements in random order.
>
> It's better to use random.sample() than random.shuffle().

If you're iterating through the whole list and don't need to preserve
the original order (as was the case here) random.shuffle() is better.


Aren't-absolutist-opinions-cool?-ly yr's,

Carl Banks


From http  Wed Jul  1 21:37:38 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 18:37:38 -0700
Subject: Trying to use sets for random selection,
	but the pop() method  returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
Message-ID: <7xr5wzzwyl.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> If you're iterating through the whole list and don't need to preserve
> the original order (as was the case here) random.shuffle() is better.

1. Random.sample avoids iterating through the whole list when it can.

2. Say you want to choose 10 random numbers between 1 and 1000000.

   random.sample(xrange(1000000), 10)

works nicely.  Doing the same with shuffle is painful.


From pavlovevidence at gmail.com  Wed Jul  1 21:46:10 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 18:46:10 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com> 
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
	<7xr5wzzwyl.fsf@ruckus.brouhaha.com>
Message-ID: <5572daf2-7149-41a7-97e5-91c4bc1e908f@n16g2000yqm.googlegroups.com>

On Jul 1, 6:37?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > If you're iterating through the whole list and don't need to preserve
> > the original order (as was the case here) random.shuffle() is better.
>
> 1. Random.sample avoids iterating through the whole list when it can.
>
> 2. Say you want to choose 10 random numbers between 1 and 1000000.
>
> ? ?random.sample(xrange(1000000), 10)
>
> works nicely. ?Doing the same with shuffle is painful.

random.shuffle() is still better when you're iterating through the
whole list as the OP was doing.

Carl Banks


From http  Wed Jul  1 22:02:46 2009
From: http (Paul Rubin)
Date: 01 Jul 2009 19:02:46 -0700
Subject: Trying to use sets for random selection,
	but the pop() method  returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com>
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
	<7xr5wzzwyl.fsf@ruckus.brouhaha.com>
	<5572daf2-7149-41a7-97e5-91c4bc1e908f@n16g2000yqm.googlegroups.com>
Message-ID: <7xtz1vu9ix.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> random.shuffle() is still better when you're iterating through the
> whole list as the OP was doing.

The OP wrote:

    I want to select, 70% random records from a List. I thougth set
    where a good idea so I tested this way: ...

That sounds like 70% of the list, not the whole list.  Note that
in addition to using time proportional to the size of the entire
lsit rather than the size of the sample, shuffle() also messes up
the order of the list.  

Why would shuffle ever be better?  It is designed for a different
purpose.  Using a function called "sample" when you want to sample
should be a no-brainer, and if using shuffle instead is ever
preferable, that should be treated as a misfeature in the "sample"
implementation, and fixed.


From pavlovevidence at gmail.com  Wed Jul  1 22:17:56 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 19:17:56 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<12eaea3c-b0f1-4109-a6ef-dc24f2bc7925@n11g2000yqb.googlegroups.com> 
	<7xd48jgb8u.fsf@ruckus.brouhaha.com>
	<00378c8a-0920-4f2a-9ec0-7abc360d857b@l2g2000vba.googlegroups.com>
	<7xr5wzzwyl.fsf@ruckus.brouhaha.com>
	<5572daf2-7149-41a7-97e5-91c4bc1e908f@n16g2000yqm.googlegroups.com>
	<7xtz1vu9ix.fsf@ruckus.brouhaha.com>
Message-ID: <263f472b-3555-4d62-b37d-fb134da5a683@r25g2000vbn.googlegroups.com>

On Jul 1, 7:02?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > random.shuffle() is still better when you're iterating through the
> > whole list as the OP was doing.
> The OP wrote:
>
> ? ? I want to select, 70% random records from a List. I thougth set
> ? ? where a good idea so I tested this way: ...

I was going by his example which went through all the items in the
list.


> That sounds like 70% of the list, not the whole list. ?Note that
> in addition to using time proportional to the size of the entire
> lsit rather than the size of the sample, shuffle() also messes up
> the order of the list. ?
>
> Why would shuffle ever be better?

Because we were talking about different things.


Carl Banks


From rtm74 at yahoo.com  Wed Jul  1 22:38:14 2009
From: rtm74 at yahoo.com (rtm74 at yahoo.com)
Date: Wed, 1 Jul 2009 19:38:14 -0700 (PDT)
Subject: Newby Windows User
Message-ID: <447092.99927.qm@web110201.mail.gq1.yahoo.com>

I am new to Python and use Windows XP. I would like to know how to run a python program file?



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/a5e04ed0/attachment-0001.html>

From bpytlik at Sun.COM  Wed Jul  1 22:48:04 2009
From: bpytlik at Sun.COM (Brock Pytlik)
Date: Wed, 01 Jul 2009 19:48:04 -0700
Subject: System default sys.path
Message-ID: <4A4C1FE4.1070901@sun.com>

Hi, I'm trying to find a way to get the value sys.path would have on a 
particular system if python was started with an empty python path. I do 
want it to include the site specific additional paths. I know I can hack 
this information myself, but I'd rather be able to get this on demand so 
that if things change in the future, I don't have grovel around looking 
for which directory string to change.

If nothing else, I think the following would satisfy my needs:
1) a variable containing the directories to use as a prefix (I think 
sys.exec_prefix and sys.prefix are what I want here)
2) a variable containing the list of suffixes that are applies to the 
prefixes, like lib/python<version>/site-packages
3) a way of handing the *.pth files

Thanks in advance for the help,
Brock


From pavlovevidence at gmail.com  Wed Jul  1 23:18:22 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 1 Jul 2009 20:18:22 -0700 (PDT)
Subject: invoking a method from two superclasses
References: <mailman.2460.1246502951.8015.python-list@python.org>
Message-ID: <24ebfdef-0832-4b78-983a-d886e56160b7@f10g2000vbf.googlegroups.com>

On Jun 30, 9:57?pm, Mitchell L Model <MLMLi... at Comcast.net> wrote:
> [Continuing the discussion about super() and __init__]
>
> The documentation of super points out that good design of
> diamond patterns require the methods to have the same
> signature throughout the diamond. That's fine for non-mixin
> classes where the diamond captures different ways of handling
> the same data.

[snip]

> The problem is that each mixin's __init__ is likely to have a
> different signature.

[snip]


Here are my recommendations for mixin classes.

1. Try to write mixins so that they don't need initializer arguments.
There's several approaches to this.  I prefer to burden the subclass
to set any attributes the mixin needs before calling super().__init__
().

class A(SomeMixin,SomeBaseClass):
    def __init__(self,arg1,arg2):
        self.some_attribute_needed_by_mixin = 10
        super().__init__(arg1,arg2)

That might seem a little weird to some (possibly because it is
impossible in C++ or Java to do that), but I find it to be a far more
versatile way for a subclass to send data to its parent.  I use it for
regular single inheritance, even.

Another possibility is to have a separate mixin initializer that is
called separately.

2. The __init__ of a mixin, if it has one, should always take *args
and **kwargs arguments, and only those arguments, and pass them as-is
to the superclass.

class SomeMixin:
    def __init__(self,*args,**kwargs):
        super().__init__(*args,**kwargs)
        self.use_somehow(self.some_attribute_needed_by_mixin)

If your mixin must have its own initializer argument, make it a
keyword-only argument, and have __init__ pop it off kwargs.

3. List mixin bases first among base classes.


I don't think Python provides an ideal way to do MI, BTW.  I believe
that's by design: MI is somewhat troublesome specifically to
discourage overuse.  As a power MI user, I am fine with this.


> I think I'd be back to having to call each mixin class's
> __init__ explicitly:

I'd say never mix super() and direct calls, for any reason.  Pick one
and go with it.


Carl Banks


From contact at xavierho.com  Wed Jul  1 23:18:42 2009
From: contact at xavierho.com (Xavier Ho)
Date: Thu, 2 Jul 2009 13:18:42 +1000
Subject: Newby Windows User
In-Reply-To: <447092.99927.qm@web110201.mail.gq1.yahoo.com>
References: <447092.99927.qm@web110201.mail.gq1.yahoo.com>
Message-ID: <2d56febf0907012018h79a6ca5bt97d3a900a4b409bf@mail.gmail.com>

Double click should work.

If it flashes up and goes away really quickly, then you need to run it under
IDLE or some kind of python shell.

Once you have Python installed, go to Start -> Run, and type in cmd to bring
up the windows command line or whatever you wanna call it.

Go to the folder where your python script is. Command is the same like macs
or linux, with cd being change directory, and such. Type e: to switch to the
e drive and so on. Note that dir lists the directory and its contents, not
ls like in mac terminals.

When you're in the same folder as your script, type the command like this:

python <file name>.py

That should do the trick. Alternatively, you can type in python and start
the python shell in the same folder.

Then you can just do import and whatever you like. :]

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Thu, Jul 2, 2009 at 12:38 PM, <rtm74 at yahoo.com> wrote:

> I am new to Python and use Windows XP. I would like to know how to run a
> python program file?
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/83fd59df/attachment-0001.html>

From wuwei23 at gmail.com  Wed Jul  1 23:41:19 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:41:19 -0700 (PDT)
Subject: Using Python to set desktop background image under Windows XP
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net> 
	<mailman.2456.1246494790.8015.python-list@python.org>
Message-ID: <ef3c772d-d935-4241-8809-c306eae21747@g19g2000yql.googlegroups.com>

On Jul 2, 8:02?am, "ELLINGHAUS, LANCE" <lance.ellingh... at hp.com>
wrote:
> Does anyone have any code that would allow setting the desktop background image under Windows XP?

It's amazing what typing "python windows desktop" into Google will
find you:

http://snippets.dzone.com/posts/show/3348

Any other searches you'd like us to do?

(Also: please post a new message instead of replying to an existing
one and changing the subject, it screws up threading)



From wuwei23 at gmail.com  Wed Jul  1 23:47:46 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:47:46 -0700 (PDT)
Subject: Getting input the scanf way
References: <mailman.2438.1246467374.8015.python-list@python.org>
Message-ID: <fcc576d0-46d7-4522-bfae-c60d53fb55fa@g1g2000yqh.googlegroups.com>

On Jul 1, 6:33?pm, "Mr.SpOOn" <mr.spoo... at gmail.com> wrote:
> I need to do some kind of interactive command line program.
>
> I mean: I run the program, it asks me for input, I type something and
> then I get the output or other questions.
> I'm not sure what is the right way to achieve this.

While the simplest way would be raw_input & print, as suggested,
there's also the cmd[1] module in the stdlib, which is what the
standard CPython interpreter uses, I believe.

[1]: http://docs.python.org/library/cmd.html


From no.email at please.post  Wed Jul  1 23:49:57 2009
From: no.email at please.post (kj)
Date: Thu, 2 Jul 2009 03:49:57 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
Message-ID: <h2hap5$qv8$2@reader1.panix.com>

In <Xns9C3BCA27ABC36duncanbooth at 127.0.0.1> Duncan Booth <duncan.booth at invalid.invalid> writes:
>So, for example:

>>>> re.compile("c").match("abcdef", 2)
><_sre.SRE_Match object at 0x0000000002C09B90>
>>>> re.compile("^c").search("abcdef", 2)
>>>>

I find this unconvincing; with re.search alone one could simply
do:

>>> re.compile("^c").search("abcdef"[2:])
<_sre.SRE_Match object at 0x75918>

No need for re.match(), at least as far as your example shows.

Maybe there are times when re.match() is more "convenient" in some
way, but it is awfully Perlish to "multiply language elements" for
the sake of this trifling convenience.

kynn


From wuwei23 at gmail.com  Wed Jul  1 23:53:37 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:53:37 -0700 (PDT)
Subject: Open Source RSS Reader in Python?
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <425d611e-ee56-4def-875e-899b2753eeb4@a7g2000yqk.googlegroups.com>

On Jul 2, 9:18?am, Alex <alex.lavoro.pro... at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?

It's always worth taking a look at PyPI. Some packages work perfectly
well as stand alone applications.

http://pypi.python.org/pypi?%3Aaction=search&term=rss&submit=search

These two look promising:
+ NewsFeed (Tk-based): http://home.arcor.de/mdoege/newsfeed/
+ urssus (QT-based): http://code.google.com/p/urssus/


From wuwei23 at gmail.com  Wed Jul  1 23:56:28 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 20:56:28 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com> 
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com> 
	<mailman.2434.1246465610.8015.python-list@python.org>
	<npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net>
Message-ID: <1e79b6bf-f33e-4267-bc61-dde6093a95e1@r33g2000yqn.googlegroups.com>

On Jul 2, 3:47?am, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> And even simpler:
> ? ? ?PASSWORD = "qwerty"
> ? ? ?MAXRETRY = 3
> ? ? ?for attempt in range(MAXRETRY):
> ? ? ? ? ?if raw_input('Enter your password: ') == PASSWORD:
> ? ? ? ? ? ? ?print 'Password confirmed'
> ? ? ? ? ? ? ?break # this exits the for loop
> ? ? ? ? ?print 'Access denied: attempt %s of %s' % (attempt+1, MAXRETRY)
> ? ? ?else:
> ? ? ? ? ?# The else for a for statement is not executed for breaks,
> ? ? ? ? ?# So indicates the end of testing without a match
> ? ? ? ? ?raise SystemExit # Or whatever you'd rather do.

Nice one, I always forget about for-else :)


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  2 00:14:36 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 02 Jul 2009 04:14:36 GMT
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
Message-ID: <pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>

On Thu, 02 Jul 2009 03:49:57 +0000, kj wrote:

> In <Xns9C3BCA27ABC36duncanbooth at 127.0.0.1> Duncan Booth
> <duncan.booth at invalid.invalid> writes:
>>So, for example:
> 
>>>>> re.compile("c").match("abcdef", 2)
>><_sre.SRE_Match object at 0x0000000002C09B90>
>>>>> re.compile("^c").search("abcdef", 2)
>>>>>
>>>>>
> I find this unconvincing; with re.search alone one could simply do:
> 
>>>> re.compile("^c").search("abcdef"[2:])
> <_sre.SRE_Match object at 0x75918>
> 
> No need for re.match(), at least as far as your example shows.

Your source string "abcdef" is tiny. Consider the case where the source 
string is 4GB of data. You want to duplicate the whole lot, minus two 
characters. Not so easy now.


> Maybe there are times when re.match() is more "convenient" in some way,
> but it is awfully Perlish to "multiply language elements" for the sake
> of this trifling convenience.

No, it's absolutely Pythonic. 


>>> import this
...
Although practicality beats purity.



-- 
Steven


From rajat.dudeja at gmail.com  Thu Jul  2 00:33:55 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Wed, 1 Jul 2009 21:33:55 -0700 (PDT)
Subject: Access NtQueryInformationProces() from Python
References: <408014003A0DA34BA5287D7A07EC089A1F94F4@EVS1.aeroflex.corp> 
	<mailman.2365.1246353019.8015.python-list@python.org>
Message-ID: <5e107810-2378-41fc-8fb5-329a943ab3bd@t13g2000yqt.googlegroups.com>

On Jun 30, 2:10?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Dudeja, Rajat wrote:
> > Hi,
>
> > I'm looking for a way to call the NtQueryInformationProces() and ReadProcessMemory() of WindowsXP from Python.
>
> > Can anyone direct me to some examples where they have been successfully called through Python?
>
> You want to look at ctypes:
>
> http://docs.python.org/library/ctypes.html?highlight=ctypes#module-ct...
>
> TJG

Thanks Tim


From david.lyon at preisshare.net  Thu Jul  2 00:40:25 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Thu, 02 Jul 2009 00:40:25 -0400
Subject: System default sys.path
In-Reply-To: <4A4C1FE4.1070901@sun.com>
References: <4A4C1FE4.1070901@sun.com>
Message-ID: <81a8195ca5ecf44f3bf9ddbfaae37bdc@preisshare.net>

On Wed, 01 Jul 2009 19:48:04 -0700, Brock Pytlik <bpytlik at Sun.COM> wrote:
> Hi, I'm trying to find a way to get the value sys.path would have on a 
> particular system if python was started with an empty python path. I do 
> want it to include the site specific additional paths. I know I can hack 
> this information myself, 

Copy the code out from site.py...


> but I'd rather be able to get this on demand so 
> that if things change in the future, I don't have grovel around looking 
> for which directory string to change.

            for index in range(len(sys.path)):
                del sys.path[0]
            site.addsitedir(self.p.python_sitepackages_path)

> If nothing else, I think the following would satisfy my needs:
> 1) a variable containing the directories to use as a prefix (I think 
> sys.exec_prefix and sys.prefix are what I want here)
> 2) a variable containing the list of suffixes that are applies to the 
> prefixes, like lib/python<version>/site-packages
> 3) a way of handing the *.pth files

What way do you want to handle them?




From stefan_ml at behnel.de  Thu Jul  2 00:50:54 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Thu, 02 Jul 2009 06:50:54 +0200
Subject: Multi thread reading a file
In-Reply-To: <mailman.2433.1246465455.8015.python-list@python.org>
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>	<op.uwdg9jthx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2433.1246465455.8015.python-list@python.org>
Message-ID: <4a4c3cae$0$31873$9b4e6d93@newsspool3.arcor-online.net>

Mag Gam wrote:
> On Wed, Jul 1, 2009 at 12:54 AM, Gabriel Genellina wrote:
>> Does the format conversion involve a significant processing time? If not,
>> the total time is dominated by the I/O time (reading and writing the file)
>> so it's doubtful you gain anything from multiple threads.
> 
> The format does inolve significant time processing each line.
>
>>> Here is the pseudo code I was thinking about:
>>>
>>> Let T  = Total number of lines in a file, Example 1000000 (1 million
>>> files)
>>> Let B = Total number of lines in a buffer, for example 10000 lines
>>>
>>>
>>> Create a thread to read until buffer
>>> Create another thread to read buffer+buffer  ( So we have 2 threads
>>> now. But since the file is zipped I have to wait until the first
>>> thread is completed. Unless someone knows of a clever technique.
>>> Write the content of thread 1 into a numpy array
>>> Write the content of thread 2 into a numpy array
>> Can you process each line independently? Is the record order important? If
>> not (or at least, some local dis-ordering is acceptable) you may use a few
>> worker threads (doing the conversion), feed them thru a Queue object, put
>> the converted lines into another Queue, and let another thread write the
>> results onto the destination file.
> 
> Yes, each line can be independent. The original file is a time series
> file which I am placing it into a Numpy array therefore I don't think
> the record order is important.  The writing is actually done when I
> place a value into a "dset" object.
> 
> Let me show you what I mean.
> reader=csv.reader(open("100000.csv"))

Have you tried if using the csv reader here is actually fast enough for
you? Maybe you can just .split(',') each line or something (no idea what
else the csv reader may do, but anyway...)


> for s,row in enumerate(reader):
>  if s!=0 and s%bufsize==0:
>       dset[s-bufsize:s] = t  #here is where I am writing the data to
> the data structure. Using a range or broadcasting.

Erm, what's "t"? And where do you think the "significant" processing time
comes from in your example? From your code, that's totally non-obvious to me.


>   #15 columns
>  if len(row) != 15:
>    break
> 
>  t[s%bufsize] = tuple(row)
> 
> #Do this all the way at the end for flushing.
> if (s%bufsize != 0):
>    dset[(s//bufsize)*bufsize:s]=t[0:s%bufsize]

If you *really* think your code is not I/O bound, but that the code for
writing the data into the NumPy array is the slow part (which I actually
doubt, but anyway), you can try writing your code in Cython, which has
direct support for writing to NumPy arrays through their buffer interface.

http://docs.cython.org/docs/numpy_tutorial.html

Stefan


From apt.shansen at gmail.com  Thu Jul  2 01:11:10 2009
From: apt.shansen at gmail.com (Stephen Hansen)
Date: Wed, 1 Jul 2009 22:11:10 -0700
Subject: What are the limitations of cStringIO.StringIO() ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
Message-ID: <7a9c25c20907012211m610dac7dr3c18c33ea33f0ed6@mail.gmail.com>

>
>
>    1. Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
>    2. Could you suggest a better way to create a string that contains the
>    concatenation of several big files ?
>
>
This isn't a limit in cStringIO.StringIO, but a limit on the amount of
memory a process is able to allocate from the OS. There's no real way
around it-- but you can take a different approach.

You have to get the memory somewhere, but if what you're combining
can't fit into memory (generally, 2 GB, but it depends on OS and
platform), you can use memory from a different source-- the hard-drive
for instance.

I would suggest you create a temporary file somewhere, and instead of
reading the contents into memory, read it in chunks and write it to
this temporary file, then go on and do the rest. That way you'll never
have so much in memory that you hit the limits. When this is done, you
can move this temporary file to where you want it, or read from it and
pass its output somewhere.

--S
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/36980e11/attachment-0001.html>

From tjreedy at udel.edu  Thu Jul  2 01:25:05 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 02 Jul 2009 01:25:05 -0400
Subject: Adding an object to the global namespace through " f_globals"
	is   that allowed ?
In-Reply-To: <4A4BC22D.70502@gmail.com>
References: <4A4BC22D.70502@gmail.com>
Message-ID: <h2hgbj$sp5$1@ger.gmane.org>

Stef Mientki wrote:
> hello,
> 
> I need to add an object's name to the global namespace.
> The reason for this is to create an environment,
> where you can add some kind of math environment,
> where no need for Python knowledge is needed.
> 
> The next statement works,
> but I'm not sure if it will have any dramatical side effects,
> other than overruling a possible object with the name A
> 
> def some_function ( ...) :
>      A = object ( ...)
>      sys._getframe(1).f_globals [ Name ] = A

global name
name = A

or is name is a string var
globals()[name] = A



From esj at harvee.org  Thu Jul  2 01:30:16 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Thu, 02 Jul 2009 01:30:16 -0400
Subject: pep 8 constants
In-Reply-To: <4A4A3FC1.5000108@tim.thechases.com>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>
	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>
	<4A48E307.50804@harvee.org> <4A49E232.6090101@tim.thechases.com>
	<4A4A2EE5.8040301@harvee.org> <4A4A3FC1.5000108@tim.thechases.com>
Message-ID: <4A4C45E8.9070309@harvee.org>

Tim Chase wrote:
>> I've tried it least two dozen editors and they all fail miserably
>> because they're focused on keyboard use (but understandable)
> [...snip...]
>> I've tried a whole bunch, like I said at least a dozen. They
>> all fail for first reasons such as inability to access all
>> functionality through keystrokes (easiest interface method
>> from speech recognition)
> 
> I'm not sure I follow which you want...you kvetch that
> they're too focused on keyboard use, but then that you can't
> access all functionality through the keyboard.

sorry. I've been living in this world for so long that I sometimes forget to
explain what's obvious inside my head. I apologize for the confusion.

The apparent conflict arises because the same term (keyboard access) is used to
describe two different problems. In the first case, the user interface model
(how you access taxes, manipulate light which (language) constructs are designed
to be efficient for your hands.  speech recognition users need an editor that
supports constructs that are efficient for the voice. One such construct is the
ability to navigate or operate on language elements by name. I've used some of
them before such as predicate, index, first method etc.

The second problem is that editors are designed to be driven by keystroke. If I
had a cross  process boundary APIPaula I can simply call the editor function to
perform to give operation. Unfortunately, today my speech recognition
environment needs to generate keystrokes to access functionality. for example,
in Emacs, when I say "delete word", the macro and marmot emits M-d

> 
> [warning, blatant vim fanaticism follows]
> 
> I use vim and can't remember the last time I used the mouse
> with it (save for occasionally lazily scrolling with the
> mouse-wheel, but you can scroll with the keyboard too), so
> it meets your "must be fully accessible through the
> keyboard" constraint.  It also has single keystroke commands
> for indenting/exdenting the current line as you mention:

you are forgiven. :-) try this experiment. Bring up the buffer full Python code
code you value them, starting in command mode, close your eyes and type a random
word. While your eyes are closed, undo that word. Every time I've tried it the
results have been mildly disastrous. If you been paying attention, I've tried to
leave speech recognition errors in place whatever didn't impede understanding
(too much) but, remember I'm getting one error in 20 errors is on average. That
means, I'll be correcting the IE errors, potentially much more dangerous errors
are regular basis. Any energy use by speech recognition must be able to cope
with a random dictation errors and let the user recover gracefully. Again, until
I started using speech recognition, I would never would've thought of this as a
failure case.

> 
>   > I know this is also counter to the Python way but having
>   > something marking and outdent would be really useful so
>   > that a vocal driven command to indent or outdent a block
>   > would be practical.
> 
> which can be done in insert-mode with control+D, control+T,
> and if you want to clear all indentation (all the way back
> to the first column), you can use "0" followed by control+D.
> Vim also allows for fairly detailed control over
> auto-indentation settings so you can match them to your
> preferences.  I suspect Emacs may be configurable to offer
> similar functionality but I'd have to defer to the emacsen
> on the list.

Yes, Emacs will, a single tab key, tab view to the indentation level specified
by the previous line unless it's already there and then it will start inventing
further. This really sucks. Sometimes, you just weary and then to  (you just
want to) go to the right place and stay there
> 
> That said, I'll be the first to admit that the vi/vim
> learning curve is more like a brick wall than a curve.
> However, I find the efficiency gains abundantly than repaid
> the time I invested to learn it well.

Yeah, I first encountered the eye in 1985. Or maybe I should say VI (Roman
numeral six).
> 
>>> Dasher[1]
>>
>> I've tried it, it's quite promising but my hands term are sufficiently
>> that I can't target accurately.
> 
> Last I tried it, it scaled the target sizes based on
> probability.  You might also try unconventional pointing
> devices for better precision.  I've seen web-cam
> eye-tracking tools which might make it a bit easier.  Or try
> a tablet input (where the motion corresponds linearly, as
> opposed to accelerated mouse motion).  Such input options
> are listed on the Dasher website, at least for those they
> tested.
> 

I like tablets. I need to buy a new one. We only problem is that most pens for
tablets are a little bit too small and hard for my hands (although they are much
better than mice). The major downfall is the buttons on the pen shaft. Damn
that's awkward to reach. I think it would need a separate tab of three buttons
that I can click and double-click independent of the pen controls.

>> Oh, another failure point. Have you ever tried to selected beach and
>> by voice. I mean I should say have you ever tried to
>> select a region by voice.
> 
> yes, not a pleasant experience.  Again, vim's modal
> interface allows for using text-objects so you can issue
> short-hand commands like
> 
>   ci"
> 
> to "[c]hange the contents [i]nside the double-quotes I'm
> currently on/withing".  The operator+motion and
> operator+textobject command syntax obviates a lot selection.
> While vim does offer a "visual" mode (akin to selection in
> other editors), I use it much less because of the power
> provided by the operator+[motion/textobject].

that's getting close to what I want to do with voice command except instead of
cryptic sequence of characters, I would say something like

string_edit = edit [<which>] string
which = first | second | third | fourth | fifth | sixth


> as you're an emacs user, my vim suggestions may sound like
> heresy. ;-)  But I suspect a skilled emacs user (or perhaps
> asking on an emacs-users list) could mimic much of the vim
> functionality.  I just can't be of much assistance there.

I really don't care what editor I use as long as it gets the job done. I have
strong preferences for always insert mode but, if I had an editor I had no
keystroke commands and everything I type went into the buffer but I committed a
complete of my speech, that would be kind of cool.
> 
> You're welcome to move it off-list...it's kinda drifted from python to
> general accessibility issues.  CC'ing c.p.l for this one in case any
> emacsen care to chime in on their suggested tweaks.

well, that you are really joined. For example, if we look at the string edit
command above, that implies he had or has the ability to properly distinguish a
string in a line of code. Think of how many ways you can express a string
triple or single quotes into different forms sometimes with  quotes nested
inside.  then take the whole object instance and know method is possible with
its type signature. This is editor work.


From Mariosky at gmail.com  Thu Jul  2 01:33:25 2009
From: Mariosky at gmail.com (Mario Garcia)
Date: Wed, 1 Jul 2009 22:33:25 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
Message-ID: <05dde563-a8f1-45d1-8f59-7740c58787ba@e21g2000yqb.googlegroups.com>


Thank you all for your input, Yes random is what I need!!
I checked the docs, and follow your comments, I will use both
random.sample and random.shuffle,and random.choice etc. !!

For this particular problem I think ramdom.shuffle() is what I need.

I was not very clear or complete in my explanation, and  I didn't
expect such a
discussion on my needs, now I'm embarrassed :) .

The list is a data set for training a machine learning algorithm. I
want to
use 70% of the records (random) for training, but then the remaining
30% are used for
validation. This is repeated a few times choose again 70% at random
for training and
the rest for validation.

With random.shuffle() I just iterate for the first 70% of the records
for training and
I just continue with the remaining 30%. This last 30% we dont care if
its random anymore,
so shuffle is doing some extra work as it was pointed out.
Conceptually something like this:

population = range(100)
training = random.sample(population,70)
validation = set(population).difference(set(training))

But I think this is more costly

Thanks Again
Mario


From rajat.dudeja at gmail.com  Thu Jul  2 01:42:43 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Wed, 1 Jul 2009 22:42:43 -0700 (PDT)
Subject: Accessing windows structures through ctypes.
Message-ID: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>

Hi,

Using ctypes can I access the windows structures like:

PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
PEB_LDR_DATA, etc?


Regards,
Rajat



From esj at harvee.org  Thu Jul  2 01:47:28 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Thu, 02 Jul 2009 01:47:28 -0400
Subject: pep 8 constants
In-Reply-To: <op.uwbx3lwla8ncjz@gnudebst>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<mailman.2273.1246252100.8015.python-list@python.org>	<a5a4183c-1dd0-40b2-bdf4-5895488c165c@t21g2000yqi.googlegroups.com>	<mailman.2306.1246290580.8015.python-list@python.org>	<025949cb$0$20671$c3e8da3@news.astraweb.com>	<4A497A5B.4040503@harvee.org>
	<op.uwbxt1wfa8ncjz@gnudebst> <op.uwbx3lwla8ncjz@gnudebst>
Message-ID: <4A4C49F0.5060306@harvee.org>

Rhodri James wrote:
> 
> Gah.  Ignore me.  I hit 'send' instead of 'cancel', after my musings 
> concluded that yes, an editor could be smart enough, but it would have to
> embed a hell of a lot of semantic knowledge of Python and it still wouldn't
> eliminate the need to speak the keyboard at times.

imagine having the same problem except that happens at random while you're
speaking and watching something else other than a screen. :-)

Yeah, it would take a lot of semantic knowledge about Python. Is it possible to
leverage compiler internals? Is it possible to gather as much information as you
can and when the system says "I don't know" you tell what you know it remembers
that for future reference?

And you're right, they're always corner cases where you'll need to speak the
keyboard or type. I've mostly resigned to accept on days when I have an absolute
hissy hissy fit because my hands hurt so bad I can't get enough painkillers
drop the pain and let me function.

In the real short term what I really want. More than anything right now is to
get back to the point where I can  pick away at writing Python again. I'm in
this really weird confluence of virtual machine hell,  the evolution of
naturally speaking under wine and the problems of telling an editor how to do
the right thing.

There's a gap between the fragile crappy way I and others operate today and the
really ideal completely voice driven  environment that exists between my ears. I
would like to move into that gap but it's sufficiently far away from what my
hands can do that I'm dependent on others and that makes me  really crazy sometimes.

>From my perspective, what I consider a reasonable intermediate step would be an
editor that has the following features:

The ability to select regions either by NaturallySpeaking Select-and-Say and
Emacs mark and point semantics.
Very deterministic indentation control. (I.e. indent x tabs or indent to "right"
level.)
ability to navigate/operate on generic language features
it would be nice if one could edit language features in a separate window again,
using Select-and-Say type interface.
another it would be nice would be the ability to look up type signatures
(classes, methods etc. and inject the appropriate template when using a
particular method. (Doesn't have to be by voice)


this level of functionality, would also make it possible to comply with PEP-8
:-) given proper easy and automatic name generation and dumpling.


From ldo at geek-central.gen.new_zealand  Thu Jul  2 01:53:09 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Thu, 02 Jul 2009 17:53:09 +1200
Subject: Making code run in both source tree and installation path
References: <mailman.2310.1246292443.8015.python-list@python.org>
	<5db6ce60-0645-40e1-b8fd-415beca46a47@l2g2000vba.googlegroups.com>
	<mailman.2428.1246465065.8015.python-list@python.org>
Message-ID: <h2hi05$3ec$2@lust.ihug.co.nz>

In message <mailman.2428.1246465065.8015.python-list at python.org>, Robert 
Kern wrote:

> On 2009-07-01 01:04, Carl Banks wrote:
>>
>> The most common way I've seen people work around this issue is to
>> throw their data files into the package directories.  Yuck.
> 
> Huh. I always found that to be a more elegant solution than hardcoding the
> data location into the program at install-time.

Think in terms of a portable OS, written to run on multiple architectures. 
Read-only data is architecture-dependent, that's why it pays to separate it 
from the code.

Otherwise you end up with a system that needs a reinstall every time the 
hardware changes.




From wuwei23 at gmail.com  Thu Jul  2 02:09:13 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 23:09:13 -0700 (PDT)
Subject: Basic question from pure beginner
References: <815232c0-e3ac-4b42-bcef-8f9881429048@c36g2000yqn.googlegroups.com>
	<b2fd9c13-47ab-45c2-8000-43085e46e0d0@a7g2000yqk.googlegroups.com> 
	<49a531ad-f6c8-4875-869f-6a694905fc72@k8g2000yqn.googlegroups.com> 
	<mailman.2434.1246465610.8015.python-list@python.org>
	<npSdnZfWM7AAAtbXnZ2dnUVZ_vGdnZ2d@pdx.net> 
	<1e79b6bf-f33e-4267-bc61-dde6093a95e1@r33g2000yqn.googlegroups.com> 
	<mailman.2466.1246512006.8015.python-list@python.org>
Message-ID: <19cbe70f-d9a0-4c77-b02a-98b943b063b7@o6g2000yqj.googlegroups.com>

Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
> ? ? ? ? There is also the getpass module to play with!

I don't think I've ever seen getpass, so thanks for pointing that out.
Unfortunately, it wouldn't have helped the OP understand why his
original code wasn't working ;)


From tkjthingone at gmail.com  Thu Jul  2 02:10:43 2009
From: tkjthingone at gmail.com (Horace Blegg)
Date: Wed, 1 Jul 2009 23:10:43 -0700
Subject: Accessing windows structures through ctypes.
In-Reply-To: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
Message-ID: <b78ad4bc0907012310w31e50429k10ac80dfa928e8b7@mail.gmail.com>

http://www.codeproject.com/KB/threads/GetNtProcessInfo.aspx

Looks rather to be pretty simple: Acquire the PED base pointer (article
explains how) and then just read that information into a struct using
ReadProcessMemory().

On Wed, Jul 1, 2009 at 10:42 PM, Rajat <rajat.dudeja at gmail.com> wrote:

> Hi,
>
> Using ctypes can I access the windows structures like:
>
> PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> PEB_LDR_DATA, etc?
>
>
> Regards,
> Rajat
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090701/30df6b5b/attachment-0001.html>

From shenyute at gmail.com  Thu Jul  2 02:11:54 2009
From: shenyute at gmail.com (Shen, Yu-Teh)
Date: Wed, 1 Jul 2009 23:11:54 -0700 (PDT)
Subject: dealloc function in python extend c module
Message-ID: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>

I create my extend type something like http://www.python.org/doc/current/extending/newtypes.html.
And my type has a member which is a pointer point to my allocate
memory ( no ref count).
ex:
---------------------------------------------------
typedef struct {
    PyObject_HEAD
    /* Type-specific fields go here. */
    mytype *p;
} noddy_NoddyObject;

And i write dealloc function like this:
---------------------------------------------------
static void
Noddy_dealloc(Noddy* self)
{
    delete p;
    self->ob_type->tp_free((PyObject*)self);
}

And I found it's strange that it didn't call dealloc when there is no
reference.

ex:
a = Noddy()
b = a
del a
del b
# i think there is no ref to the object, and it should call dealloc
but it didn't call!!!

could anyone tell me what happened?

Thanks a lot!!



From pm567426 at gmail.com  Thu Jul  2 02:13:52 2009
From: pm567426 at gmail.com (Pedram)
Date: Wed, 1 Jul 2009 23:13:52 -0700 (PDT)
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
Message-ID: <9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>

On Jul 1, 10:01?pm, Christian Heimes <li... at cheimes.de> wrote:
> Pedram schrieb:
>
> > Hello community,
> > I'm reading the CPython interpreter source code,
> > first, if you have something that I should know for better reading
> > this source code, I would much appreciate that :)
> > second, in intobject.c file, I read the following code in
> > fill_free_list function that I couldn't understand:
> > <code>while (--q > p)
> > ? ? Py_TYPE(q) = (struct _typeobject *)(q-1);
> > Py_TYPE(q) = NULL;
> > </code>
> > What does it mean?
>
> The code is abusing the ob_type member to store a single linked, NULL
> terminated list of free integer objects. It's a tricky optimization you
> don't have to understand in order to understand the rest of the code.
>
> And no, the code in ctypes.h is totally unrelated to the free list in
> intobject.c.
>
> Christian

Thanks for reply.
I totally understood the fill_free_list() function. Thanks.
But I have problems in understanding the PyInt_FromLong(). Here's the
code:

PyObject *
PyInt_FromLong(long ival)
{
	register PyIntObject *v;
#if NSMALLNEGINTS + NSMALLPOSINTS > 0
	if (-NSMALLNEGINTS <= ival && ival < NSMALLPOSINTS) {
		v = small_ints[ival + NSMALLNEGINTS];
		Py_INCREF(v);
#ifdef COUNT_ALLOCS
		if (ival >= 0)
			quick_int_allocs++;
		else
			quick_neg_int_allocs++;
#endif
		return (PyObject *) v;
	}
#endif
	if (free_list == NULL) {
		if ((free_list = fill_free_list()) == NULL)
			return NULL;
	}

	v = free_list; // <-- No problem till here :)
	free_list = (PyIntObject *)Py_TYPE(v);
	PyObject_INIT(v, &PyInt_Type);
	v->ob_ival = ival;
	return (PyObject *) v;
}

I understood that small numbers (between -5 and 256) are referenced to
small_ints list. Others have to store in PyIntBlock, am I right? OK,
no problem till 'v = free_list;' but can't understand the line
'free_list = (PyIntObject *)Py_TYPE(v);' :(. Where free_list
referenced to? Don't this correct that free_list have to be referenced
to another free block so next time the function called v store in this
location?
Sorry for my bad English. I hope you could understand me :)


From israelu at elbit.co.il  Thu Jul  2 02:17:00 2009
From: israelu at elbit.co.il (iu2)
Date: Wed, 1 Jul 2009 23:17:00 -0700 (PDT)
Subject: wxPython: Plaing widgets in status bar
Message-ID: <335b69b5-eabe-443e-842d-fb6ec95a3bd3@x3g2000yqa.googlegroups.com>

Hi all,

I try to placs widgets (button, static text labels) in a status bar,
wxPython.
>From the examples I could place them using exact positioning by the
status bar methof GetFieldRect.
In this case I need to add an EVT_SIZER handler to keep the widgets in
their propotional places
within the status bar.

I try to do it without exact positioning, that is using a sizer.
I tried adding a sizer directly to the status bar, but it didn't work,
it layed out the widgets
at the upper left corner of the status bar, atop of each other.
I tried adding a panel to the status bar and then adding the widgets
to it., but then the widgets partially
cover the status bar. They also don't keep their propotional
positions, although I used it in the sizer.Add method.

How can I position widgets within the status bar like positioning them
in a frame?

thanks


From wuwei23 at gmail.com  Thu Jul  2 02:25:38 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 1 Jul 2009 23:25:38 -0700 (PDT)
Subject: Accessing windows structures through ctypes.
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
Message-ID: <eac94481-c76b-46f8-bac6-48794fc264af@d4g2000yqa.googlegroups.com>

On Jul 2, 3:42?pm, Rajat <rajat.dud... at gmail.com> wrote:
> Using ctypes can I access the windows structures like:
>
> PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> PEB_LDR_DATA, etc?

ctypes.wintypes lists all of the Windows structures included with the
module.

You should be able to use ctypes.Structure class to roll your own:

http://docs.python.org/library/ctypes.html#structured-data-types
http://code.activestate.com/recipes/208699/
http://msdn.microsoft.com/en-us/library/ms684855(VS.85).aspx



From esj at harvee.org  Thu Jul  2 02:33:10 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Thu, 02 Jul 2009 02:33:10 -0400
Subject: pep 8 constants
In-Reply-To: <pan.2009.06.30.05.45.18@REMOVE.THIS.cybersource.com.au>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<mailman.2273.1246252100.8015.python-list@python.org>	<a5a4183c-1dd0-40b2-bdf4-5895488c165c@t21g2000yqi.googlegroups.com>	<mailman.2306.1246290580.8015.python-list@python.org>	<025949cb$0$20671$c3e8da3@news.astraweb.com>	<mailman.2352.1246329493.8015.python-list@python.org>
	<pan.2009.06.30.05.45.18@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A4C54A6.9030707@harvee.org>

Steven D'Aprano wrote:
> That assumes that every word is all caps. In practice, for real-life 
> Python code, I've tripled the vocal load of perhaps one percent of your 
> utterances, which cuts your productivity by 2%.
> 
> If you have 10000 words in you per day, and one percent get wrapped with 
> a leading and trailing "capslock", you have:
> 
> 9900 regular words plus 100 constants
> 
> versus
> 
> 9700 regular words plus 100 constants plus 200 by capslock.
> 
> Your productivity goes down by 200 words out of 10,000, or two percent.

oh I wish it was so simple. I would absolutely you if it was that simple the
real world. Somehow, I fear that you wouldn't understand unless you sat next to
me and watch me try to write code to  a variety of standards.

In practice, my experience says that with a really good  speech driven
environment for programming, IT, vocal load probably by a quarter to a half and
be more compliant with current fashion for naming.
> 
> 
>>>> Heck, have you ever noticed how most Python smart editors can't even
>>>> indent properly according to local contexts. Emacs is the only one and
>>>> even that one sometimes fails
>>> I use kwrite for editing, and I can't say I've ever noticed a failure.
>> okay, it fails from a speech recognition user perspective. Put the
>> cursor on the line and hit the tab key. Insert spaces/tabs in the line
>> of text. Not good for speech recognition. If  mess of indentation and
>> hit the tab key, it doesn't automatically indent to the right location.
>> I'll be damned if I'm in the sit there speaking
>> "tabkeytabkeytabkeytabkeytabkey" because the error should take care of
>> it for me and save my voice. Like I said, Emacs does it correctly and
>> nobody else does as far as I can tell.
> 
> I don't understand what you're describing.
> 
> If you set kwrite to use "Python style" indent mode, then starting a new 
> line will automatically indent to either the current indent level, or one 
> extra indent level if the line ends with a colon. You shouldn't need to 
> indent forward more than one level at a time when writing Python code, 
> although you will need to dedent multiple levels on occasion.

I recognize your confusion. It's very common when describing this problem. If I
had some way of making a movie of what  and describing, obviously be more clear.
I'll see if I can make a movie with my camera that demonstrates the problem.  It
probably won't happen fast but, what I tried your editor, it failed   with a
trivial effort.  I think I just hit the tab key multiple times in different
places on the line. In all cases it did the wrong thing. For me, the right thing
is to force the line to the right indentation based on the previous line to
matter how may times you get the tab key or where you are on that line when you
hit the tab key. I could be in the middle of the line, the end of line, start a
line, the start of the string and if I hit a tab key, that line should go to
exactly the right place stayed there no matter how me more times I typed a tab key.

But this might be what you're getting confused. What I'm really asking for is
the ability to say "force indent" and have the line indent exactly correctly
based on context. It doesn't have to be the tab key. The tab key is the method
of convenience.

> 
>> You're looking at it from the classical anti-accommodation perspective.
>> Don't change the convention, give us the tools so we can comply with
>> what the rest of you do. 
> 
> Just a minute. You're the one who started this discussion rejecting the 
> convention. Your first post started off:
> 
> "I reject this convention..."
> 
> and then finished with
> 
> "so I reject pep 8 because I have no voice safe alternative"
> 
> Do you blame us for reading this as a protest against uppercase 
> identifiers?

it's a protest against  identifiers that increase vocal or hand load.  It's also
protest against decisions people make without awareness of the implications, in
this case, increasing the barriers against disabled programmers.

> 
> Now you're saying you're happy for us to keep the all-uppercase 
> convention and just want better tools. Okay, you want better tools. 
> Great. If you're attempting to raise the profile of disabled programmers, 
> you've done so, but what exactly are you expecting?

I waffle back and forth on that. I recognize my opinion  matters as much as a
piss hole in the snow. But the unintentional discrimination really gets to me.
In case you're wondering, I feel this way about many forms of bad
design/exclusionary practices. Some I can even do something about.

my expectations are evolving. I wanted to raise awareness, like you said, I've
done that. But now, I'd like to turn it into action. As I said in another post,
the editor that would let me get back to writing Python relatively easily again
doesn't exist. It's not the flashy wonderful no keystrokes whatsoever condition
but it's significantly better than the current Emacs/VI/Python editor du jour.
it would be able to operate open loop with relation to speech recognition but I
also have an idea of how to add closed loop capability to make it more efficient
as that capability becomes available.

> I've already said it's your right to reject the convention for your own 
> code. Go right ahead. This is only a problem if you're editing other 
> people's code which is using uppercase constants.

exactly. If I'm unable to comply with local conventions, I cannot work within an
organization and be an active member of the team. This is one example of what I
mean by unintentional discriminatory effects of a given decision.  rhetorical
devices aside, I think the right way to deal with accessibility issues and
decisions leading to discrimination is to make the appropriate tools if possible
for the individual. But I'm sure that would be a very long discussion we would
have over a couple of beers.

> 
> You've rejected capslock red capslock because it takes three utterances, 
> but said you use constant_red instead. That's two utterances, saving you 
> only one. If you actually have to say the underscore, your convention 
> takes six syllables versus five for my idea.

 my opinion comes out of  experience. Strictly numerically speaking, you are
correct. But if you look at recognition accuracy, pacing of speech, and flow of
words through the vocal track, my solution is  gentler on the vocal tract, body
stress (tension anticipating this recognition errors), and cognition (don't need
a spare any mental cycles on  anticipation of failure and how to correct). I can
just say focused on what I'm dictating. Additionally, making corrections of my
style is easier (i.e. you can make the correction) but the form you propose with
Locks (see, this is one of those "I'm going to bust a In your ass" type errors)
cannot be corrected. He can only be deleted and restated.

I apologize for being a "I'm the expert know it all" on this but, I really do
have 15 years experience with these kind of failures and I like to think I know
something about the topic.

>>> Especially when these coding conventions are entirely optional.
>> these conventions are religion for some special if you want to
>> contribute code.
> 
> Does your editor have search and replace? Before you contribute code, do 
> a global replacement of constant_red for RED.

Yes it does and, it you know as well as I do that global search replace blindly
leads to disastrous errors and, increased testing, and the problem doesn't go
away because you always modify your code later.
> 
> 
>> But look at the bigger issue.
> 
> Yes, we get it. It sucks to have a physical disability. The universe 
> isn't arranged to make it easy for those who do, and even systems built 
> by people are only indifferently suitable.

fine. I'll put down that particular baseball bat stop hitting you over the head
with it.  I still think you should try living with naturally speaking for a week
or two.

> 
> So, let's get down to practical matters:
> 
> Do you wish to register a protest against all-caps constants in PEP 8?

only if I had a rational, reasonable alternative. Let me chew on that.
> 
> Do you wish to ask the Python Dev team to rethink their decision?

only when I have rational, reasonable alternatives.
> 
> Do you wish to raise the profile of disabled programmers?

yes. Not exactly sure of the best way but I would like to do that through
providing tools enabling them to participate on equal footing with not yet
disabled programmers.  I really don't like saying "take pity on the poor
programmers with broken hands." I'd rather say "you need talent? Here's a pool
you have previously thrown away but they can now generate code faster than the
keyboard users.

> Do you wish to start a project developing a better, smarter editor, and 
> are looking for volunteers?

yes. This also opens up a great big giant hairball. Specifically, how do you
edit on one machine but do all of your testing and debugging on the second (i.e.
edit on Windows, do everything else on Linux. Unfortunately, I have quite a bit
of scar tissue with this as well and can tell you all about how the different
network file systems fail in special and wonderful ways.

but let's deal with the editor first.

yes, I would like to start a smarter editor project and the only way I could do
it is with volunteers. I would not be able to write code for it until it had
progressed significantly.  What I can do is provide the knowledge of a
first-generation system should look like, evolutionary corrections thereafter. I
can also help with interfacing Python two to speech recognition and creation of
grammars and their code.

I'm a strong believer in recycling existing systems. We might get lucky and make
it better for them to.

if you're willing to help me find volunteers, get this started (I only need some
nudges in the right direction), I gladly accept your help and your knowledge.


From rajat.dudeja at gmail.com  Thu Jul  2 02:50:43 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Wed, 1 Jul 2009 23:50:43 -0700 (PDT)
Subject: Accessing windows structures through ctypes.
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
	<eac94481-c76b-46f8-bac6-48794fc264af@d4g2000yqa.googlegroups.com>
Message-ID: <8c8b5cf2-bc77-4633-96ca-e3b908430492@z14g2000yqa.googlegroups.com>


> > Using ctypes can I access the windows structures like:
>
> > PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> > PEB_LDR_DATA, etc?
>
> ctypes.wintypes lists all of the Windows structures included with the
> module.
>
> You should be able to use ctypes.Structure class to roll your own:

Thanks Alex. As you suggested, I'm trying to implemenet the below
structure, windows PEB, in Python:

typedef struct _PEB {
    BYTE Reserved1[2];
    BYTE BeingDebugged;
    BYTE Reserved2[21];
    PPEB_LDR_DATA LoaderData;
    PRTL_USER_PROCESS_PARAMETERS ProcessParameters;
    BYTE Reserved3[520];
    PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine;
    BYTE Reserved4[136];
    ULONG SessionId;
} PEB;

My equivalent Python structure is:
class PEB(Structure):
    _fields_ = [("Reserved1", wintypes.BYTE * 2),
                ("BeingDebugged", wintypes.BYTE),
                ("Reserved2", wintypes.BYTE * 2),
                ("Reserved3", c_void_p),
                ("Ldr", pointer(PEB_LDR_DATA)),
                ("ProcessParameters", pointer
(RTL_USER_PROCESS_PARAMETERS)),
                ("Reserved4", wintypes.BYTE * 104),
                ("Reserved5", c_void_p),
                (),
                ("Reserved6", wintypes.BYTE),
                ("Reserved7", c_void_p),
                ("SessionId", c_ulong)]

I'm not sure what needs to go in the above empty tuple for
"PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine" (in Original
PEB).

Please suggest.


From sgm at objexx.com  Thu Jul  2 02:54:25 2009
From: sgm at objexx.com (SK)
Date: Wed, 1 Jul 2009 23:54:25 -0700 (PDT)
Subject: multiprocessing and freezing on Windows
Message-ID: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>

Is there a method for freezing a Python 2.6 app using multiprocessing
on Windows using PyInstaller or py2exe that works? It is trying to
call my executable instead of python.exe when the process starts and
passes it --multiprocessing-fork . Adding a freeze_support() to my
main doesn't help. Do I have to bundle all of Python and use
set_executable() to point to the bundled python.exe? I can't find any
workable information on the canonical way to do this.

Thanks!


From clp2 at rebertia.com  Thu Jul  2 03:02:41 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 2 Jul 2009 00:02:41 -0700
Subject: Open Source RSS Reader in Python?
In-Reply-To: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <50697b2c0907020002o16536566h948856375ea3289e@mail.gmail.com>

On Wed, Jul 1, 2009 at 4:18 PM, Alex<alex.lavoro.propio at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?

Straw for GTK/GNOME is written in Python, though it's somewhat inactive.
http://projects.gnome.org/straw/
http://strawreader.wordpress.com/

Cheers,
Chris
-- 
http://blog.rebertia.com


From eckhardt at satorlaser.com  Thu Jul  2 03:11:48 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Thu, 02 Jul 2009 09:11:48 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
Message-ID: <k63uh6-861.ln1@satorlaser.homedns.org>

Hi!

I'm currently converting my bioware to handle Python code and I have
stumbled across a problem...

Simple scenario: I have a handle to a resource. This handle allows me to
manipulate the resource in various ways and it also represents ownership.
Now, when I put this into a class, instances to that class can be shared,
using Python's reference counting. What I'm missing is a way to
automatically release the resource, something which I would do in the
destructor in C++.

Any ideas how to solve this?

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From 4564 at 755189.45  Thu Jul  2 03:42:09 2009
From: 4564 at 755189.45 (Enrico)
Date: Thu, 2 Jul 2009 09:42:09 +0200
Subject: Accessing windows structures through ctypes.
References: <26f1eb49-f972-40c7-aa9e-d4d6e3079d40@i6g2000yqj.googlegroups.com>
	<eac94481-c76b-46f8-bac6-48794fc264af@d4g2000yqa.googlegroups.com>
	<8c8b5cf2-bc77-4633-96ca-e3b908430492@z14g2000yqa.googlegroups.com>
Message-ID: <4a4c650c$0$1115$4fafbaef@reader3.news.tin.it>

"Rajat" <rajat.dudeja at gmail.com> ha scritto nel messaggio
news:8c8b5cf2-bc77-4633-96ca-e3b908430492 at z14g2000yqa.googlegroups.com...
>
> > > Using ctypes can I access the windows structures like:
> >
> > > PROCESS_INFORMATION_BLOCK, Process Environment Block(PEB),
> > > PEB_LDR_DATA, etc?
> >
> > ctypes.wintypes lists all of the Windows structures included with the
> > module.
> >
> > You should be able to use ctypes.Structure class to roll your own:
>
> Thanks Alex. As you suggested, I'm trying to implemenet the below
> structure, windows PEB, in Python:
>
> typedef struct _PEB {
>     BYTE Reserved1[2];
>     BYTE BeingDebugged;
>     BYTE Reserved2[21];
>     PPEB_LDR_DATA LoaderData;
>     PRTL_USER_PROCESS_PARAMETERS ProcessParameters;
>     BYTE Reserved3[520];
>     PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine;
>     BYTE Reserved4[136];
>     ULONG SessionId;
> } PEB;
>
> My equivalent Python structure is:
> class PEB(Structure):
>     _fields_ = [("Reserved1", wintypes.BYTE * 2),
>                 ("BeingDebugged", wintypes.BYTE),
>                 ("Reserved2", wintypes.BYTE * 2),
>                 ("Reserved3", c_void_p),
>                 ("Ldr", pointer(PEB_LDR_DATA)),
>                 ("ProcessParameters", pointer
> (RTL_USER_PROCESS_PARAMETERS)),
>                 ("Reserved4", wintypes.BYTE * 104),
>                 ("Reserved5", c_void_p),
>                 (),
>                 ("Reserved6", wintypes.BYTE),
>                 ("Reserved7", c_void_p),
>                 ("SessionId", c_ulong)]
>
> I'm not sure what needs to go in the above empty tuple for
> "PPS_POST_PROCESS_INIT_ROUTINE PostProcessInitRoutine" (in Original
> PEB).
>
> Please suggest.

PostProcessInitRoutine should be a callback function or something similar.
It should be enough to define a type

PostProcessInitRoutine = WINFUNCTYPE(...parameters...)

and use this.

Regards,
Enrico




From Joachim at Strombergson.com  Thu Jul  2 03:57:14 2009
From: Joachim at Strombergson.com (=?UTF-8?B?Sm9hY2hpbSBTdHLDtm1iZXJnc29u?=)
Date: Thu, 02 Jul 2009 09:57:14 +0200
Subject: PEP 376
In-Reply-To: <h2f7jt$j33$1@south.jnrs.ja.net>
References: <mailman.2410.1246390911.8015.python-list@python.org><h2ec5l$820$1@lust.ihug.co.nz><73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
Message-ID: <4A4C685A.8020300@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

Richard Brodie wrote:
> "Joachim Str?mbergson" <Joachim at Strombergson.com> wrote in message 
> news:mailman.2422.1246418400.8015.python-list at python.org...
> 
>> Even so, choosing md5 in 2009 for something that (hopefully) will be
>> used in years is a bad design decision. It creates a dependency for to
>> an algorithm that all sensible recommendations point you to move away
>> from.
> 
> Why not write the field as algorithm:value?
> 
> e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4
> 
> Installers can fallback to using hashlib.new(), so you can plug in a new
> algorithm without changing the PEP or the installer code. 

+1

Good idea and future proof as well as being simple.

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMaFoACgkQZoPr8HT30QHVxQCfWqKprUaAQxaxTfYJVfIp8+FC
5UIAn2cWNoMe+sdNO4BSZG7e+19qkqvl
=Id7s
-----END PGP SIGNATURE-----


From petshmidt at googlemail.com  Thu Jul  2 04:25:29 2009
From: petshmidt at googlemail.com (Tep)
Date: Thu, 2 Jul 2009 01:25:29 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
Message-ID: <02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>

On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
> someone wrote:
> > Hello,
>
> > how can I replace '?' sign from string? Or do split at that character?
> > Getting unicode error if I try to do it:
>
> > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > 1: ordinal not in range(128)
>
> > Thanks, Pet
>
> > script is # -*- coding: UTF-8 -*-
>
> It sounds like you're mixing bytestrings with Unicode strings. I can't
> be any more helpful because you haven't shown the code.

Oh, I'm sorry. Here it is

def cleanInput(input)
    return input.replace('?', '')


From petshmidt at googlemail.com  Thu Jul  2 04:31:46 2009
From: petshmidt at googlemail.com (Tep)
Date: Thu, 2 Jul 2009 01:31:46 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
	<02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>
Message-ID: <9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>

On 2 Jul., 10:25, Tep <petshm... at googlemail.com> wrote:
> On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > someone wrote:
> > > Hello,
>
> > > how can I replace '?' sign from string? Or do split at that character?
> > > Getting unicode error if I try to do it:
>
> > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > > 1: ordinal not in range(128)
>
> > > Thanks, Pet
>
> > > script is # -*- coding: UTF-8 -*-
>
> > It sounds like you're mixing bytestrings with Unicode strings. I can't
> > be any more helpful because you haven't shown the code.
>
> Oh, I'm sorry. Here it is
>
> def cleanInput(input)
> ? ? return input.replace('?', '')

I also need:

#input is html source code, I have problem with only this character
#input = 'foo ? bar'
#return should be foo
def splitInput(input)
    parts = input.split(' ? ')
    return parts[0]


Thanks!


From Joachim at Strombergson.com  Thu Jul  2 04:32:04 2009
From: Joachim at Strombergson.com (=?UTF-8?B?Sm9hY2hpbSBTdHLDtm1iZXJnc29u?=)
Date: Thu, 02 Jul 2009 10:32:04 +0200
Subject: PEP368 and pixeliterators
Message-ID: <4A4C7084.60000@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

I just read the PEP368 and really liked the proposed idea, sound like a
great battery addition to include in the std lib:

http://www.python.org/dev/peps/pep-0368/

One question/idea though: The proposed iterator will iterate over all
pixels in a line, but only one line. The example code looks like this:

# iterate over an image
for line in rgb_image:
    for pixel in line:
        # swap red and blue, and set green to 0
        pixel.value = pixel.b, 0, pixel.r


But, wouldn't it be more Pythonic and simpler to have an iterator that
iterates over all pixels in an image? Starting with upper left corner
and moving left-right and (line by line) to lower right. This would
change the code above to:

for pixel in rgb_image:
    # swap red and blue, and set green to 0
    pixel.value = pixel.b, 0, pixel.r


The idea I'm having is that fundamentally the image is made up of a 2D
array of pixels, not rows of pixels. And having the iterator focus on
pixels instead make then more sense, no?

Or if possible have two iterators.


Otherwise, big thumbs up for PEP 368 as well as having PEP:s for driving
the language development process in an orderly and well documented way.

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMcIQACgkQZoPr8HT30QFkcgCgzxb9JS2l87B/nkpf05FLDjY5
RPQAni2yPxKjCd4lM/qMBNhjp8HHg/PZ
=9gB/
-----END PGP SIGNATURE-----


From jeremiah.dodds at gmail.com  Thu Jul  2 04:44:44 2009
From: jeremiah.dodds at gmail.com (Jeremiah Dodds)
Date: Thu, 2 Jul 2009 09:44:44 +0100
Subject: Determining if a function is a method of a class within a 
	decorator
In-Reply-To: <4A4AB863.1020205@ilm.com>
References: <mailman.2346.1246323698.8015.python-list@python.org>
	<ac046931-02d7-4067-a9a3-2f2cd9bc3bca@c9g2000yqm.googlegroups.com>
	<4A4AB863.1020205@ilm.com>
Message-ID: <12cbbbfc0907020144s6d7848aci65bab54a726a9f22@mail.gmail.com>

On Wed, Jul 1, 2009 at 2:14 AM, David Hirschfield <davidh at ilm.com> wrote:

>  Unfortunately that still requires two separate decorators, when I was
> hoping there was a way to determine if I was handed a function or method
> from within the same decorator.
>
> Seems like there really isn't, so two decorators is the way to go.
> Thanks,
> -David
>
>
This is a really horrible idea, but it may work:

If you can rely on your code using the word "self", you could use the
inspect module to look at the arguments of the function being decorated, and
dispatch based on that. The idea itself feels extremely dirty though.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/cc45876a/attachment-0001.html>

From __peter__ at web.de  Thu Jul  2 05:11:34 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 11:11:34 +0200
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
	<9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>
Message-ID: <h2htjt$t6e$00$1@news.t-online.com>

Pedram wrote:

> On Jul 1, 10:01 pm, Christian Heimes <li... at cheimes.de> wrote:
>> Pedram schrieb:
>>
>> > Hello community,
>> > I'm reading the CPython interpreter source code,
>> > first, if you have something that I should know for better reading
>> > this source code, I would much appreciate that :)
>> > second, in intobject.c file, I read the following code in
>> > fill_free_list function that I couldn't understand:
>> > <code>while (--q > p)
>> > Py_TYPE(q) = (struct _typeobject *)(q-1);
>> > Py_TYPE(q) = NULL;
>> > </code>
>> > What does it mean?
>>
>> The code is abusing the ob_type member to store a single linked, NULL
>> terminated list of free integer objects. It's a tricky optimization you
>> don't have to understand in order to understand the rest of the code.
>>
>> And no, the code in ctypes.h is totally unrelated to the free list in
>> intobject.c.
>>
>> Christian
> 
> Thanks for reply.
> I totally understood the fill_free_list() function. Thanks.
> But I have problems in understanding the PyInt_FromLong(). Here's the
> code:
> 
> PyObject *
> PyInt_FromLong(long ival)
> {
> register PyIntObject *v;
> #if NSMALLNEGINTS + NSMALLPOSINTS > 0
> if (-NSMALLNEGINTS <= ival && ival < NSMALLPOSINTS) {
> v = small_ints[ival + NSMALLNEGINTS];
> Py_INCREF(v);
> #ifdef COUNT_ALLOCS
> if (ival >= 0)
> quick_int_allocs++;
> else
> quick_neg_int_allocs++;
> #endif
> return (PyObject *) v;
> }
> #endif
> if (free_list == NULL) {
> if ((free_list = fill_free_list()) == NULL)
> return NULL;
> }
> 
> v = free_list; // <-- No problem till here :)
> free_list = (PyIntObject *)Py_TYPE(v);
> PyObject_INIT(v, &PyInt_Type);
> v->ob_ival = ival;
> return (PyObject *) v;
> }
> 
> I understood that small numbers (between -5 and 256) are referenced to
> small_ints list. Others have to store in PyIntBlock, am I right? OK,
> no problem till 'v = free_list;' but can't understand the line
> 'free_list = (PyIntObject *)Py_TYPE(v);' :(. Where free_list
> referenced to? Don't this correct that free_list have to be referenced
> to another free block so next time the function called v store in this
> location?
> Sorry for my bad English. I hope you could understand me :)

Well, if I understand fill_free_list() correctly, you haven't ;) It only 
makes sense together with the allocation code in PyInt_FromLong().

Py_TYPE(v) translates to v->ob_type, and in fill_free_list() that field was 
abused(*) to hold a pointer to the previous item in the array of free 
integers, thereby temporarily turning it into a linked list.

Assuming that free_list pointed to block->objects[10] in the current 
PyIntBlock it will now point to block->objects[9].

When block->objects[0] is reached free_list will be set to NULL as block-
>objects[0]->ob_type was initialized with NULL by the line

Py_TYPE(q) = NULL; /* in fill_free_list() */

The next call of PyInt_FromLong() will then trigger the allocation of a new 
block.

Peter

(*) It may help if you think of the objects array as a

union linked {
    linked *next;
    PyInt_Object obj;
};




From davitadze.tengiz at gmail.com  Thu Jul  2 05:23:00 2009
From: davitadze.tengiz at gmail.com (Tengiz Davitadze)
Date: Thu, 2 Jul 2009 13:23:00 +0400
Subject: Need Help
Message-ID: <2f0bc6280907020223kf2701au81da279a5f8fabaf@mail.gmail.com>

Hello. I can't find a wright mail address. If you can help me I need to get
an information about UNICODE. I am georgian and I need to write programs on
georgian language . If you can transfer this mail or send me a wright mail
about encoding or unicode information.

-- 
Tengiz Davitadze
{
programing Future
}
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/8e46519f/attachment-0001.html>

From sebastian.schabe at gmx.de  Thu Jul  2 05:40:12 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Thu, 02 Jul 2009 11:40:12 +0200
Subject: deleting certain entries in numpy array
In-Reply-To: <mailman.2440.1246489510.8015.python-list@python.org>
References: <4a4b7763$1@news.fhg.de>
	<mailman.2440.1246489510.8015.python-list@python.org>
Message-ID: <4a4c7fd9$1@news.fhg.de>

Robert Kern schrieb:
> First, convert the pos array to integers, and just the columns with 
> indices in them:
> 
>   ipos = pos[:,:2].astype(int)
> 
> Now check the values in the mask corresponding to these positions:
> 
>   mask_values = mask[ipos[:,0], ipos[:,1]]
> 
> Now extract the rows from the original pos array where mask_values is 
> nonzero:
> 
>   result = pos[mask_values != 0]
> 

Great!!! That's the way I wanted.

After reading the numpy reference guide I supposed the delete function 
was not the right way, but that it's all about cerrect indexing. But I 
didn't really know how.

So thanks a lot, also to Ben.

 >
 > You will want to ask numpy questions on the numpy mailing list.
 >
 >   http://www.scipy.org/Mailing_Lists
 >

I ever thought news-groups are the right way for questions like this. 
And the mailing list page just confuses me, but I'm trying to get used 
to it.


Sebastian


From bearophileHUGS at lycos.com  Thu Jul  2 05:50:17 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 2 Jul 2009 02:50:17 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
Message-ID: <6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>

Ulrich Eckhardt:
> a way to automatically release the resource, something
> which I would do in the destructor in C++.

Is this helpful?
http://effbot.org/pyref/with.htm

Bye,
bearophile


From gagsl-py2 at yahoo.com.ar  Thu Jul  2 06:10:17 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 07:10:17 -0300
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
Message-ID: <op.uwfqjfgfx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 01 Jul 2009 12:49:31 -0300, Scott David Daniels  
<Scott.Daniels at acm.org> escribi?:

> Gabriel Genellina wrote:
>> ...
>> def convert(in_queue, out_queue):
>>   while True:
>>     row = in_queue.get()
>>     if row is None: break
>>     # ... convert row
>>     out_queue.put(converted_line)
>
> These loops work well with the two-argument version of iter,
> which is easy to forget, but quite useful to have in your bag
> of tricks:
>
>      def convert(in_queue, out_queue):
>          for row in iter(in_queue.get, None):
>              # ... convert row
>              out_queue.put(converted_line)

Yep, I always forget about that variant of iter() -- very handy!

-- 
Gabriel Genellina



From eckhardt at satorlaser.com  Thu Jul  2 06:12:19 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Thu, 02 Jul 2009 12:12:19 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
Message-ID: <3pduh6-g52.ln1@satorlaser.homedns.org>

Bearophile wrote:
> Ulrich Eckhardt:
>> a way to automatically release the resource, something
>> which I would do in the destructor in C++.
> 
> Is this helpful?
> http://effbot.org/pyref/with.htm

Yes, it aims in the same direction. However, I'm not sure this applies to my
case. The point is that the resource handle is not just used locally in a
restricted scope but it is allocated and stored. The 'with' is something
that makes sense in the context of mutex locking, where you have a
well-defined critical section. What I need is something similar to open(),
which returs a file. When the last reference to that object goes out of
scope, the underlying file object is closed.

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From __peter__ at web.de  Thu Jul  2 06:46:27 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 12:46:27 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
Message-ID: <h2i35q$mp4$01$1@news.t-online.com>

Ulrich Eckhardt wrote:

> Bearophile wrote:
>> Ulrich Eckhardt:
>>> a way to automatically release the resource, something
>>> which I would do in the destructor in C++.
>> 
>> Is this helpful?
>> http://effbot.org/pyref/with.htm
> 
> Yes, it aims in the same direction. However, I'm not sure this applies to
> my case. The point is that the resource handle is not just used locally in
> a restricted scope but it is allocated and stored. The 'with' is something
> that makes sense in the context of mutex locking, where you have a
> well-defined critical section. 

Isn't that exactly what RAII does?

> What I need is something similar to open(),
> which returs a file. When the last reference to that object goes out of
> scope, the underlying file object is closed.

You can go ahead and implement a __del__() method. It will often work in 
CPython, but you get no guarantees, especially when you have reference 
cycles and with other Python implementations that don't use refcounting.

Peter



From pm567426 at gmail.com  Thu Jul  2 06:55:42 2009
From: pm567426 at gmail.com (Pedram)
Date: Thu, 2 Jul 2009 03:55:42 -0700 (PDT)
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
	<9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>
	<h2htjt$t6e$00$1@news.t-online.com>
Message-ID: <7c8e96a1-cbb2-4036-9aa1-1ecdfd84cca8@j32g2000yqh.googlegroups.com>

On Jul 2, 1:11?pm, Peter Otten <__pete... at web.de> wrote:
> Pedram wrote:
> > On Jul 1, 10:01 pm, Christian Heimes <li... at cheimes.de> wrote:
> >> Pedram schrieb:
>
> >> > Hello community,
> >> > I'm reading the CPython interpreter source code,
> >> > first, if you have something that I should know for better reading
> >> > this source code, I would much appreciate that :)
> >> > second, in intobject.c file, I read the following code in
> >> > fill_free_list function that I couldn't understand:
> >> > <code>while (--q > p)
> >> > Py_TYPE(q) = (struct _typeobject *)(q-1);
> >> > Py_TYPE(q) = NULL;
> >> > </code>
> >> > What does it mean?
>
> >> The code is abusing the ob_type member to store a single linked, NULL
> >> terminated list of free integer objects. It's a tricky optimization you
> >> don't have to understand in order to understand the rest of the code.
>
> >> And no, the code in ctypes.h is totally unrelated to the free list in
> >> intobject.c.
>
> >> Christian
>
> > Thanks for reply.
> > I totally understood the fill_free_list() function. Thanks.
> > But I have problems in understanding the PyInt_FromLong(). Here's the
> > code:
>
> > PyObject *
> > PyInt_FromLong(long ival)
> > {
> > register PyIntObject *v;
> > #if NSMALLNEGINTS + NSMALLPOSINTS > 0
> > if (-NSMALLNEGINTS <= ival && ival < NSMALLPOSINTS) {
> > v = small_ints[ival + NSMALLNEGINTS];
> > Py_INCREF(v);
> > #ifdef COUNT_ALLOCS
> > if (ival >= 0)
> > quick_int_allocs++;
> > else
> > quick_neg_int_allocs++;
> > #endif
> > return (PyObject *) v;
> > }
> > #endif
> > if (free_list == NULL) {
> > if ((free_list = fill_free_list()) == NULL)
> > return NULL;
> > }
>
> > v = free_list; // <-- No problem till here :)
> > free_list = (PyIntObject *)Py_TYPE(v);
> > PyObject_INIT(v, &PyInt_Type);
> > v->ob_ival = ival;
> > return (PyObject *) v;
> > }
>
> > I understood that small numbers (between -5 and 256) are referenced to
> > small_ints list. Others have to store in PyIntBlock, am I right? OK,
> > no problem till 'v = free_list;' but can't understand the line
> > 'free_list = (PyIntObject *)Py_TYPE(v);' :(. Where free_list
> > referenced to? Don't this correct that free_list have to be referenced
> > to another free block so next time the function called v store in this
> > location?
> > Sorry for my bad English. I hope you could understand me :)
>
> Well, if I understand fill_free_list() correctly, you haven't ;) It only
> makes sense together with the allocation code in PyInt_FromLong().
>
> Py_TYPE(v) translates to v->ob_type, and in fill_free_list() that field was
> abused(*) to hold a pointer to the previous item in the array of free
> integers, thereby temporarily turning it into a linked list.
>
> Assuming that free_list pointed to block->objects[10] in the current
> PyIntBlock it will now point to block->objects[9].
>
> When block->objects[0] is reached free_list will be set to NULL as block-
>
> >objects[0]->ob_type was initialized with NULL by the line
>
> Py_TYPE(q) = NULL; /* in fill_free_list() */
>
> The next call of PyInt_FromLong() will then trigger the allocation of a new
> block.
>
> Peter
>
> (*) It may help if you think of the objects array as a
>
> union linked {
> ? ? linked *next;
> ? ? PyInt_Object obj;
>
>
>
>
>
> };
>
>

Oh, I got it! What a wonderful implementation! :o
Thanks so much Peter. You made my day :) I didn't read the code
carefully.

>
> ;)
>


From no.email at please.post  Thu Jul  2 07:19:40 2009
From: no.email at please.post (kj)
Date: Thu, 2 Jul 2009 11:19:40 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
Message-ID: <h2i54b$eg3$1@reader1.panix.com>

In <pan.2009.07.02.04.14.35 at REMOVE.THIS.cybersource.com.au> Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:

>On Thu, 02 Jul 2009 03:49:57 +0000, kj wrote:

>> In <Xns9C3BCA27ABC36duncanbooth at 127.0.0.1> Duncan Booth
>> <duncan.booth at invalid.invalid> writes:
>>>So, for example:
>> 
>>>>>> re.compile("c").match("abcdef", 2)
>>><_sre.SRE_Match object at 0x0000000002C09B90>
>>>>>> re.compile("^c").search("abcdef", 2)
>>>>>>
>>>>>>
>> I find this unconvincing; with re.search alone one could simply do:
>> 
>>>>> re.compile("^c").search("abcdef"[2:])
>> <_sre.SRE_Match object at 0x75918>
>> 
>> No need for re.match(), at least as far as your example shows.

>Your source string "abcdef" is tiny. Consider the case where the source 
>string is 4GB of data. You want to duplicate the whole lot, minus two 
>characters. Not so easy now.

I'm sure that it is possible to find cases in which the *current*
implementation of re.search() would be inefficient, but that's
because this implementation is perverse, which, I guess, is ultimately
the point of my original post.  Why privilege the special case of
a start-of-string anchor?  What if you wanted to apply an end-anchored
pattern to some prefix of your 4GB string?  Why not have a special
re method for that?  And another for every possible special case?

If the concern is efficiency for such cases, then simply implement
optional offset and length parameters for re.search(), to specify
any arbitrary substring to apply the search to.  To have a special-case
re.match() method in addition to a general re.search() method is
antithetical to language minimalism, and plain-old bizarre.  Maybe
there's a really good reason for it, but it has not been mentioned
yet.

kj


From nils at ccsg.de  Thu Jul  2 07:30:44 2009
From: nils at ccsg.de (=?ISO-8859-1?Q?Nils_R=FCttershoff?=)
Date: Thu, 02 Jul 2009 13:30:44 +0200
Subject: performance problem with time.strptime()
Message-ID: <4A4C9A64.9030507@ccsg.de>

Hi everyone,

In my free time I translate scripts from open source projects or write
my own, to train my python skills. ATM I convert the aplogmerge.pl from
awstats. It merges multiple apache logfiles and sort the output by the
timestamps of each line.  My first version of this script hasn't a good
performance, so I started profiling. It turned out that the script spend
much time for converting the timestamps of the line into a struct_time
object. Here a code example (Python 2.6.2 on Ubuntu 7.10):

Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

def strptime():
    m = Rec.match(Line)
    if m:
        date_string = m.group(1)
	# date_string example: '02/Jul/2009:01:50:26'
        return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")

with timeit this functions takes approximate 125 sec and 29.004.081
function calls (I've configured timeit with 1.000.000 runs). A look at
the output of cProfile told me that more than the half time is spent in
locale.py:

  1000002   11.712    0.000   19.592    0.000 locale.py:316(normalize)

  1000002    3.639    0.000   23.231    0.000 locale.py:382(_parse_localename)

  1000002    5.162    0.000   30.271    0.000 locale.py:481(getlocale)



I studied the time documentation and thought that I had to set TZ in os
environ:

os.environ['TZ'] = 'Europe/Berlin'

time.set()


but that had no effect. I don't know why time.strptime() looks every
time for my locale. Maybe it's a problem with my OS locale... However.
I've introduced a work around, which works perfectly for my problem. For
time comparison I could use any sort of time representation and so I
convert to epoch:

# needed to translate month str to dig repr

Shortmonth = {'Jan' : '01',

              'Feb' : '02',

              'Mar' : '03',

              'Apr' : '04',

              'May' : '05',

              'Jun' : '06',

              'Jul' : '07',

              'Aug' : '08',

              'Sep' : '09',

              'Oct' : '10',

              'Nov' : '11',

              'Dec' : '12'}

Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")

Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

def epoch():

    m = Rec.match(Line)

    if m:

        result = m.groupdict()

        date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)

        date_tuple = map(int,date_tuple)

        return time.mktime(date_tuple)


with this workaround I had a speed up to 4 times; it tooks only 31 sec
with only 5.000.009 function calls. Maybe this helps some of you, who
had the similar problems with time conversion....

...But one big question remains: Why time.strptime() checks everytime
the locale? had I missed something or could I have a problem with my OS
locale?

With python 3.1 there is no difference, unless that time.strptime() took
approx 12 sec longer... :(

regards, Nils



Here a complete test script:

#!/opt/python/2.6.2/bin/python

import time

import timeit

import cProfile

import re

# needed to tranlate month str to dig repr

Shortmonth = {'Jan' : '01',

              'Feb' : '02',

              'Mar' : '03',

              'Apr' : '04',

              'May' : '05',

              'Jun' : '06',

              'Jul' : '07',

              'Aug' : '08',

              'Sep' : '09',

              'Oct' : '10',

              'Nov' : '11',

              'Dec' : '12'}

Rec1 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")

Rec2 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")

Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

def epoch():

    m = Rec1.match(Line)

    if m:

        result = m.groupdict()

        date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)

        date_tuple = map(int,date_tuple)

        return time.mktime(date_tuple)

def strptime():

    m = Rec2.match(Line)

    if m:

        date_string = m.group(1)

        return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")

if __name__ == "__main__":

    t1 = timeit.Timer("epoch()","from __main__ import epoch")

    t2 = timeit.Timer("strptime()", "from __main__ import strptime")

    cProfile.run("t1.timeit();print")

    print ""

    cProfile.run("t2.timeit();print")




From simon at brunningonline.net  Thu Jul  2 07:34:10 2009
From: simon at brunningonline.net (Simon Brunning)
Date: Thu, 2 Jul 2009 12:34:10 +0100
Subject: Need Help
In-Reply-To: <2f0bc6280907020223kf2701au81da279a5f8fabaf@mail.gmail.com>
References: <2f0bc6280907020223kf2701au81da279a5f8fabaf@mail.gmail.com>
Message-ID: <8c7f10c60907020434u26e0518el6045d23cd89c4bcf@mail.gmail.com>

2009/7/2 Tengiz Davitadze <davitadze.tengiz at gmail.com>:
> Hello. I can't find a wright mail address. If you can help me I need to get
> an information about UNICODE. I am georgian and I need to write programs on
> georgian language . If you can transfer this mail or send me a wright mail
> about encoding or unicode information.

Our chief link is
<http://www.joelonsoftware.com/articles/Unicode.html>.
<http://www.joelonsoftware.com/articles/Unicode.html> and
<http://effbot.org/zone/unicode-objects.htm>. Our two links are
<http://effbot.org/zone/unicode-objects.htm> and
<http://www.joelonsoftware.com/articles/Unicode.html>. And
<http://www.amk.ca/python/howto/unicode>. Our *three* links are
<http://effbot.org/zone/unicode-objects.htm>,
<http://www.joelonsoftware.com/articles/Unicode.html>, and
<http://www.amk.ca/python/howto/unicode>. And
<http://catb.org/esr/faqs/smart-questions.html>. Our *four*...no...
*Amongst* our links.... Amongst our linkry are such elements as
<http://effbot.org/zone/unicode-objects.htm>,
<http://www.joelonsoftware.com/articles/Unicode.html>.... I'll come in
again.

-- 
Cheers,
Simon B.


From Caseyweb at gmail.com  Thu Jul  2 07:45:22 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Thu, 2 Jul 2009 04:45:22 -0700 (PDT)
Subject: performance problem with time.strptime()
References: <mailman.2479.1246534276.8015.python-list@python.org>
Message-ID: <6a2cc3a6-0e5c-4a43-bcf7-416a77253f97@h2g2000yqg.googlegroups.com>

On Jul 2, 7:30?am, Nils R?ttershoff <n... at ccsg.de> wrote:

> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'

I'm not sure how much it will help but if you are only using the regex
to get the date/time group element, it might be faster to replace the
regex with:

>>> date_string = Line.split()[3][1:-1]


From ziade.tarek at gmail.com  Thu Jul  2 07:55:30 2009
From: ziade.tarek at gmail.com (=?ISO-8859-1?Q?Tarek_Ziad=E9?=)
Date: Thu, 2 Jul 2009 13:55:30 +0200
Subject: PEP 376
In-Reply-To: <4A4C685A.8020300@Strombergson.com>
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net> <4A4C685A.8020300@Strombergson.com>
Message-ID: <94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>

2009/7/2 Joachim Str?mbergson <Joachim at strombergson.com>:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Aloha!
>
> Richard Brodie wrote:
>> "Joachim Str?mbergson" <Joachim at Strombergson.com> wrote in message
>> news:mailman.2422.1246418400.8015.python-list at python.org...
>>
>>> Even so, choosing md5 in 2009 for something that (hopefully) will be
>>> used in years is a bad design decision. It creates a dependency for to
>>> an algorithm that all sensible recommendations point you to move away
>>> from.
>>
>> Why not write the field as algorithm:value?
>>
>> e.g. sha1:8590b685654367e3eba70dc00df7e45e88c21da4
>>
>> Installers can fallback to using hashlib.new(), so you can plug in a new
>> algorithm without changing the PEP or the installer code.
>
> +1
>
> Good idea and future proof as well as being simple.

The prefix is a good idea but since it's just a checksum to control
that the file hasn't changed
what's wrong with using a weak hash algorithm like md5 or now sha1 ?

If someone wants to modify a file of a distribution he can recreate
the checksum as well,
the only secured way to prevent that would be to use gpg keys but
isn't that overkill for what we need ?

e.g. making sure a file wasn't modified when distutils uninstalls a
distribution.

Tarek


From hniksic at xemacs.org  Thu Jul  2 07:55:39 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Thu, 02 Jul 2009 13:55:39 +0200
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
Message-ID: <87k52rwb7o.fsf@busola.homelinux.net>

kj <no.email at please.post> writes:

> For a recovering Perl-head like me it is difficult to understand
> why Python's re module offers both match and search.  Why not just
> use search with a beginning-of-string anchor?

I need re.match when parsing the whole string.  In that case I never
want to search through the string, but process the whole string with
some regulat expression, for example when tokenizing.  For example:

    pos = 0
    while pos != len(s):
        match = TOKEN_RE.match(s, pos)
        if match:
            process_token(match)
            pos = match.end()
        else:
            raise ParseError('invalid syntax at position %d' % pos)


From davea at ieee.org  Thu Jul  2 08:05:12 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 02 Jul 2009 08:05:12 -0400
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <k63uh6-861.ln1@satorlaser.homedns.org>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
Message-ID: <4A4CA278.4050604@ieee.org>

Ulrich Eckhardt wrote:
> Hi!
>
> I'm currently converting my bioware to handle Python code and I have
> stumbled across a problem...
>
> Simple scenario: I have a handle to a resource. This handle allows me to
> manipulate the resource in various ways and it also represents ownership.
> Now, when I put this into a class, instances to that class can be shared,
> using Python's reference counting. What I'm missing is a way to
> automatically release the resource, something which I would do in the
> destructor in C++.
>
> Any ideas how to solve this?
>
> Uli
>
>   
As someone else pointed out, 'with' is the first line of defense.  It 
makes the stuff you could already do with try/except/finally much easier 
to get right.

Look also at 'del' a command in the language which explicitly deletes an 
object.

But I'm guessing you want something that automatically deletes objects 
whenever the last reference disappears.  That's an implementation 
detail, not a language guarantee.  In particular CPython does what you 
want, by using reference counting.  That's the only Python I've used, so 
it's only hearsay when I say that other implementations, (maybe Cython 
or Jython) do not all work the same way.

In CPython, any object whose *last* reference goes away, will get 
immediately deleted.  So if you avoid circular references, it should do 
just what you want.  Orphaned circular references are caught by the 
garbage collector, which runs periodically, but is non-deterministic.

Two more caveats.  Exceptions tend to hang onto stuff in their near 
vicinity, and I can't tell you the algorithm for what happens.  But an 
explicit del in the except clause can probably handle that.

Finally, closures can hang onto stuff.  So if you have nested functions, 
or lambda functions, it's possible they're going to keep things longer 
than you realize.





From lists at cheimes.de  Thu Jul  2 08:10:55 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 02 Jul 2009 14:10:55 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <4A4CA278.4050604@ieee.org>
References: <k63uh6-861.ln1@satorlaser.homedns.org> <4A4CA278.4050604@ieee.org>
Message-ID: <h2i84f$v2t$1@ger.gmane.org>

Dave Angel wrote:
> Look also at 'del' a command in the language which explicitly deletes an
> object.

No, you are either explaining it the wrong way or you have been fallen
for a common misinterpretation of the del statement. The del statement
only removes the object from the current scope. This means it decreases
the reference count by one. It does *not* remove the object.

Christian



From Caseyweb at gmail.com  Thu Jul  2 08:17:28 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Thu, 2 Jul 2009 05:17:28 -0700 (PDT)
Subject: PEP368 and pixeliterators
References: <mailman.2475.1246523526.8015.python-list@python.org>
Message-ID: <2aeeb8de-c8f3-4e9d-98f7-d1fa71e1f3a3@d4g2000yqa.googlegroups.com>

On Jul 2, 4:32?am, Joachim Str?mbergson <Joac... at Strombergson.com>
wrote:
> But, wouldn't it be more Pythonic and simpler to have an iterator that
> iterates over all pixels in an image? Starting with upper left corner
> and moving left-right and (line by line) to lower right. This would
> change the code above to:

Unless I'm totally misreading the PEP, the author does provide both
iterators.  Quoting the PEP:

Non-planar images offer the following additional methods:

pixels() -> iterator[pixel]

  Returns an iterator that iterates over all the pixels in the image,
  starting from the top line and scanning each line from left to
right.
  See below for a description of the pixel objects.

__iter__() -> iterator[line]

  Returns an iterator that iterates over all the lines in the image,
  from top to bottom. See below for a description of the line objects.


From __peter__ at web.de  Thu Jul  2 08:54:50 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 14:54:50 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<mailman.2482.1246536325.8015.python-list@python.org>
Message-ID: <h2iamg$qk$02$1@news.t-online.com>

Dave Angel wrote:

> But I'm guessing you want something that automatically deletes objects
> whenever the last reference disappears.  That's an implementation
> detail, not a language guarantee.  In particular CPython does what you
> want, by using reference counting.  That's the only Python I've used, so
> it's only hearsay when I say that other implementations, (maybe Cython
> or Jython) do not all work the same way.

Here are some examples from Kubuntu 9.04's zoo of python implementations:

$ cat del.py
import sys
print sys.version

class A(object):
    def __init__(self, x):
        self.x = x
    def __del__(self):
        print "releasing A(%r)" % self.x

def f():
    a = A("local in function")
f()

a = A("global (one ref)")

c = A("global (cycle)")
c.a = c
del c

b = A("global (no refs)")
del b

print "about to quit"

$ python del.py
2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
[GCC 4.3.3]
releasing A('local in function')
releasing A('global (no refs)')
about to quit
releasing A('global (one ref)')

$ jython del.py
2.2.1
about to quit

$ ipy del.py
2.4.0 (IronPython 1.1.1 (1.1.1) on .NET 2.0.50727.42)
about to quit
releasing A('global (no refs)')
releasing A('global (cycle)')
releasing A('local in function')

Unhandled Exception: System.ArgumentException: I/O operation on closed file
  at IronPython.Runtime.PythonFile.ThrowIfClosed () [0x00000]
  at IronPython.Runtime.PythonFile.Write (System.String s) [0x00000]
$

IronPython sometimes segfaulted.

Peter



From nils at ccsg.de  Thu Jul  2 09:00:11 2009
From: nils at ccsg.de (=?ISO-8859-1?Q?Nils_R=FCttershoff?=)
Date: Thu, 02 Jul 2009 15:00:11 +0200
Subject: performance problem with time.strptime()
In-Reply-To: <6a2cc3a6-0e5c-4a43-bcf7-416a77253f97@h2g2000yqg.googlegroups.com>
References: <mailman.2479.1246534276.8015.python-list@python.org>
	<6a2cc3a6-0e5c-4a43-bcf7-416a77253f97@h2g2000yqg.googlegroups.com>
Message-ID: <4A4CAF5B.2040502@ccsg.de>

Hi Casey
Casey Webster wrote:
> On Jul 2, 7:30 am, Nils R?ttershoff <n... at ccsg.de> wrote:
>
>   
>> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
>> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>>     
>
> I'm not sure how much it will help but if you are only using the regex
> to get the date/time group element, it might be faster to replace the
> regex with:
>
>   
>>>> date_string = Line.split()[3][1:-1]
>>>>         

Indeed this would give a little speed up (by 1000000 iteration approx
3-4 sec). But this would be only a small piece of the cake. Although thx :)

The problem is that time.strptime() consult locale.py for each
iteration. Here the hole cProfile trace:

first with epoch and second with strptime (condensed):

         5000009 function calls in 33.084 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000   33.084   33.084 <string>:1(<module>)
        1    2.417    2.417   33.084   33.084 <timeit-src>:2(inner)
  1000000    9.648    0.000   30.667    0.000 time_test.py:30(epoch)
        1    0.000    0.000   33.084   33.084 timeit.py:177(timeit)
  1000000    3.711    0.000    3.711    0.000 {built-in method groupdict}
  1000000    4.318    0.000    4.318    0.000 {built-in method match}
        1    0.000    0.000    0.000    0.000 {gc.disable}
        1    0.000    0.000    0.000    0.000 {gc.enable}
        1    0.000    0.000    0.000    0.000 {gc.isenabled}
  1000000    7.764    0.000    7.764    0.000 {map}
        1    0.000    0.000    0.000    0.000 {method 'disable' of
'_lsprof.Profiler' objects}
  1000000    5.225    0.000    5.225    0.000 {time.mktime}
        2    0.000    0.000    0.000    0.000 {time.time}

################################################################

         29000009 function calls in 124.449 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000  124.449  124.449 <string>:1(<module>)
        1    2.244    2.244  124.449  124.449 <timeit-src>:2(inner)
  1000000    3.500    0.000   33.559    0.000 _strptime.py:27(_getlang)
  1000000   41.814    0.000  100.754    0.000 _strptime.py:295(_strptime)
  1000000    4.010    0.000  104.764    0.000
_strptime.py:453(_strptime_time)
  1000000   11.647    0.000   19.529    0.000 locale.py:316(normalize)
  1000000    3.638    0.000   23.167    0.000
locale.py:382(_parse_localename)
  1000000    5.120    0.000   30.059    0.000 locale.py:481(getlocale)
  1000000    7.242    0.000  122.205    0.000 time_test.py:37(strptime)
        1    0.000    0.000  124.449  124.449 timeit.py:177(timeit)
  1000000    1.771    0.000    1.771    0.000 {_locale.setlocale}
  1000000    1.735    0.000    1.735    0.000 {built-in method __enter__}
  1000000    1.626    0.000    1.626    0.000 {built-in method end}
  1000000    3.854    0.000    3.854    0.000 {built-in method groupdict}
  1000000    1.646    0.000    1.646    0.000 {built-in method group}
  2000000    8.409    0.000    8.409    0.000 {built-in method match}
        1    0.000    0.000    0.000    0.000 {gc.disable}
        1    0.000    0.000    0.000    0.000 {gc.enable}
        1    0.000    0.000    0.000    0.000 {gc.isenabled}
  2000000    2.942    0.000    2.942    0.000 {len}
        1    0.000    0.000    0.000    0.000 {method 'disable' of
'_lsprof.Profiler' objects}
  3000000    4.552    0.000    4.552    0.000 {method 'get' of 'dict'
objects}
  1000000    2.072    0.000    2.072    0.000 {method 'index' of 'list'
objects}
  1000000    1.517    0.000    1.517    0.000 {method 'iterkeys' of
'dict' objects}
  2000000    3.113    0.000    3.113    0.000 {method 'lower' of 'str'
objects}
  2000000    3.233    0.000    3.233    0.000 {method 'replace' of 'str'
objects}
  2000000    2.953    0.000    2.953    0.000 {method 'toordinal' of
'datetime.date' objects}
  1000000    1.476    0.000    1.476    0.000 {method 'weekday' of
'datetime.date' objects}
  1000000    4.332    0.000  109.097    0.000 {time.strptime}
        2    0.000    0.000    0.000    0.000 {time.time}

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/9b9cdd1f/attachment-0001.html>

From davea at ieee.org  Thu Jul  2 09:00:44 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 02 Jul 2009 09:00:44 -0400
Subject: performance problem with time.strptime()
In-Reply-To: <4A4C9A64.9030507@ccsg.de>
References: <4A4C9A64.9030507@ccsg.de>
Message-ID: <4A4CAF7C.9040800@ieee.org>

Nils R?ttershoff wrote:
> Hi everyone,
>
> In my free time I translate scripts from open source projects or write
> my own, to train my python skills. ATM I convert the aplogmerge.pl from
> awstats. It merges multiple apache logfiles and sort the output by the
> timestamps of each line.  My first version of this script hasn't a good
> performance, so I started profiling. It turned out that the script spend
> much time for converting the timestamps of the line into a struct_time
> object. Here a code example (Python 2.6.2 on Ubuntu 7.10):
>
> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>
> def strptime():
>     m = Rec.match(Line)
>     if m:
>         date_string = m.group(1)
> 	# date_string example: '02/Jul/2009:01:50:26'
>         return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")
>
> with timeit this functions takes approximate 125 sec and 29.004.081
> function calls (I've configured timeit with 1.000.000 runs). A look at
> the output of cProfile told me that more than the half time is spent in
> locale.py:
>
>   1000002   11.712    0.000   19.592    0.000 locale.py:316(normalize)
>
>   1000002    3.639    0.000   23.231    0.000 locale.py:382(_parse_localename)
>
>   1000002    5.162    0.000   30.271    0.000 locale.py:481(getlocale)
>
>
>
> I studied the time documentation and thought that I had to set TZ in os
> environ:
>
> os.environ['TZ'] = 'Europe/Berlin'
>
> time.set()
>
>
> but that had no effect. I don't know why time.strptime() looks every
> time for my locale. Maybe it's a problem with my OS locale... However.
> I've introduced a work around, which works perfectly for my problem. For
> time comparison I could use any sort of time representation and so I
> convert to epoch:
>
> # needed to translate month str to dig repr
>
> Shortmonth = {'Jan' : '01',
>
>               'Feb' : '02',
>
>               'Mar' : '03',
>
>               'Apr' : '04',
>
>               'May' : '05',
>
>               'Jun' : '06',
>
>               'Jul' : '07',
>
>               'Aug' : '08',
>
>               'Sep' : '09',
>
>               'Oct' : '10',
>
>               'Nov' : '11',
>
>               'Dec' : '12'}
>
> Rec = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")
>
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>
> def epoch():
>
>     m = Rec.match(Line)
>
>     if m:
>
>         result = m.groupdict()
>
>         date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)
>
>         date_tuple = map(int,date_tuple)
>
>         return time.mktime(date_tuple)
>
>
> with this workaround I had a speed up to 4 times; it tooks only 31 sec
> with only 5.000.009 function calls. Maybe this helps some of you, who
> had the similar problems with time conversion....
>
> ...But one big question remains: Why time.strptime() checks everytime
> the locale? had I missed something or could I have a problem with my OS
> locale?
>
> With python 3.1 there is no difference, unless that time.strptime() took
> approx 12 sec longer... :(
>
> regards, Nils
>
>
>
> Here a complete test script:
>
> #!/opt/python/2.6.2/bin/python
>
> import time
>
> import timeit
>
> import cProfile
>
> import re
>
> # needed to tranlate month str to dig repr
>
> Shortmonth = {'Jan' : '01',
>
>               'Feb' : '02',
>
>               'Mar' : '03',
>
>               'Apr' : '04',
>
>               'May' : '05',
>
>               'Jun' : '06',
>
>               'Jul' : '07',
>
>               'Aug' : '08',
>
>               'Sep' : '09',
>
>               'Oct' : '10',
>
>               'Nov' : '11',
>
>               'Dec' : '12'}
>
> Rec1 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(?P<day>\d{2})/(?P<month>\w+)/(?P<year>\d{4}):(?P<hour>\d{2}):(?P<min>\d{2}):(?P<sec>\d{2})\s\+\d{4}\].*")
>
> Rec2 = re.compile(r"^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\s-\s\d+\s\[(\d{2}/\w+/\d{4}:\d{2}:\d{2}:\d{2})\s\+\d{4}\].*")
>
> Line = '1.2.3.4 - 4459 [02/Jul/2009:01:50:26 +0200] "GET /foo HTTP/1.0" 200 - "-" "www.example.org" "-" "-" "-"'
>
> def epoch():
>
>     m = Rec1.match(Line)
>
>     if m:
>
>         result = m.groupdict()
>
>         date_tuple = (result["year"], Shortmonth[result["month"]], result["day"], result["hour"], result["min"], result["sec"], -1, -1, -1)
>
>         date_tuple = map(int,date_tuple)
>
>         return time.mktime(date_tuple)
>
> def strptime():
>
>     m = Rec2.match(Line)
>
>     if m:
>
>         date_string = m.group(1)
>
>         return time.strptime(date_string, "%d/%b/%Y:%H:%M:%S")
>
> if __name__ == "__main__":
>
>     t1 = timeit.Timer("epoch()","from __main__ import epoch")
>
>     t2 = timeit.Timer("strptime()", "from __main__ import strptime")
>
>     cProfile.run("t1.timeit();print")
>
>     print ""
>
>     cProfile.run("t2.timeit();print")
>
>
>
>   
As you say, if you don't actually need the datetime fields, why waste 
time generating them.  You gained a lot more than the time spent in 
locale(), so your algorithm must be faster than the one in strptime().  
That frequently happens when you write a special case for code which is 
otherwise general.

Notice that only a quarter of the time is spent in locale logic (30.271 
secs).  You can't add up the three terms since they're measuring the 
same thing.  Every call to getlocale() results in a call to

_parse_localename(), so the cumulative times of the latter are already included in the cumulative times in getlocale().

Why does it need to call locale() ?  How else is it going to know how to spell the 11th month?





From Joachim at Strombergson.com  Thu Jul  2 09:15:18 2009
From: Joachim at Strombergson.com (=?UTF-8?B?Sm9hY2hpbSBTdHLDtm1iZXJnc29u?=)
Date: Thu, 02 Jul 2009 15:15:18 +0200
Subject: PEP 376
In-Reply-To: <94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
References: <mailman.2410.1246390911.8015.python-list@python.org>	
	<h2ec5l$820$1@lust.ihug.co.nz>	
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>	
	<mailman.2422.1246418400.8015.python-list@python.org>	
	<h2f7jt$j33$1@south.jnrs.ja.net>
	<4A4C685A.8020300@Strombergson.com>
	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
Message-ID: <4A4CB2E6.8010607@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

Tarek Ziad? wrote:
> The prefix is a good idea but since it's just a checksum to control
> that the file hasn't changed
> what's wrong with using a weak hash algorithm like md5 or now sha1 ?

Because it creates a dependency to an old algorithm that should be
deprecated. Also using MD5, even for a thing like this might make people
belive that it is an ok algorithm to use - "Hey, it is used by the
default install in Python, so it must be ok, right?"

If we flip the argument around: Why would you want to use MD5 instead of
SHA-256? For the specific use case the performance will not (should not)
be an issue.

As I wrote a few mails ago, it is time to move forward from MD5 and
designing something in 2009 that will be around for many years that uses
MD5 is (IMHO) a bad design decision.

> If someone wants to modify a file of a distribution he can recreate
> the checksum as well,
> the only secured way to prevent that would be to use gpg keys but
> isn't that overkill for what we need ?

Actually, adding this type of security would IMHO be a good idea.

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMsuYACgkQZoPr8HT30QELagCghfYyHyK5jnkS8DlaQ2ZX4KR8
W+YAniWSvWRvm47/xGu0thTaYioETY94
=2x3X
-----END PGP SIGNATURE-----


From Joachim at Strombergson.com  Thu Jul  2 09:16:36 2009
From: Joachim at Strombergson.com (=?ISO-8859-1?Q?Joachim_Str=F6mbergson?=)
Date: Thu, 02 Jul 2009 15:16:36 +0200
Subject: PEP368 and pixeliterators
In-Reply-To: <2aeeb8de-c8f3-4e9d-98f7-d1fa71e1f3a3@d4g2000yqa.googlegroups.com>
References: <mailman.2475.1246523526.8015.python-list@python.org>
	<2aeeb8de-c8f3-4e9d-98f7-d1fa71e1f3a3@d4g2000yqa.googlegroups.com>
Message-ID: <4A4CB334.9080505@Strombergson.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Aloha!

Casey Webster wrote:
> Unless I'm totally misreading the PEP, the author does provide both
> iterators.  Quoting the PEP:
> 
> Non-planar images offer the following additional methods:
> 
> pixels() -> iterator[pixel]
> 
>   Returns an iterator that iterates over all the pixels in the image,
>   starting from the top line and scanning each line from left to
> right.
>   See below for a description of the pixel objects.

Ah! I knew there was a reason for me wearing glasses. ;-)

Go PEP368!

- --
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning.
========================================================================
Kryptoblog - IT-s?kerhet p? svenska
http://www.strombergson.com/kryptoblog
========================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkpMszQACgkQZoPr8HT30QGmVACfezmlZ+K93exuIEoUDJyzNzgM
3dcAn1x4Ghu9AlMKEme2og4sK4TwhXaR
=bNbl
-----END PGP SIGNATURE-----


From davea at dejaviewphoto.com  Thu Jul  2 09:21:40 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Thu, 02 Jul 2009 09:21:40 -0400
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <h2i84f$v2t$1@ger.gmane.org>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<4A4CA278.4050604@ieee.org> <h2i84f$v2t$1@ger.gmane.org>
Message-ID: <4A4CB464.80607@dejaviewphoto.com>

Christian Heimes wrote:
> Dave Angel wrote:
>   
>> Look also at 'del' a command in the language which explicitly deletes an
>> object.
>>     
>
> No, you are either explaining it the wrong way or you have been fallen
> for a common misinterpretation of the del statement. The del statement
> only removes the object from the current scope. This means it decreases
> the reference count by one. It does *not* remove the object.
>
> Christian
>
>
>   
You're right of course.  What I was trying to say was it deletes the 
reference to the object.  Unlike obj = None, del obj removes the 
reference (attribute) entirely. Although I don't know what it should be 
called if it's a local variable.  Perhaps it "unbinds" the name.

DaveA



From Mariosky at gmail.com  Thu Jul  2 09:27:36 2009
From: Mariosky at gmail.com (Mario Garcia)
Date: Thu, 2 Jul 2009 06:27:36 -0700 (PDT)
Subject: Trying to use sets for random selection, but the pop() method 
	returns items in order
References: <c64d1ee4-7316-45f6-9737-e561f8841b40@24g2000yqm.googlegroups.com>
	<05dde563-a8f1-45d1-8f59-7740c58787ba@e21g2000yqb.googlegroups.com>
Message-ID: <32f177b3-f305-4ff7-be64-ed161eb7c38d@h11g2000yqb.googlegroups.com>



This could be better:

>>> import random
>>> population = range(10)
>>> choice = random.choice(population)
>>> population.remove(choice)
>>> print population
>>> print population
[0, 1, 2, 3, 4, 5, 6, 8, 9]

That was my idea with the previous pop(), remove from the population a
certain number of elements at random.
In the docs pop is defined as:
 Remove and return an arbitrary element from the set.
My mistake: arbitrary is not the same as random :(

Mario




From lie.1296 at gmail.com  Thu Jul  2 09:33:38 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 13:33:38 GMT
Subject: pep 8 constants
In-Reply-To: <mailman.2471.1246516416.8015.python-list@python.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<mailman.2273.1246252100.8015.python-list@python.org>	<a5a4183c-1dd0-40b2-bdf4-5895488c165c@t21g2000yqi.googlegroups.com>	<mailman.2306.1246290580.8015.python-list@python.org>	<025949cb$0$20671$c3e8da3@news.astraweb.com>	<mailman.2352.1246329493.8015.python-list@python.org>	<pan.2009.06.30.05.45.18@REMOVE.THIS.cybersource.com.au>
	<mailman.2471.1246516416.8015.python-list@python.org>
Message-ID: <SG23m.2218$ze1.1019@news-server.bigpond.net.au>

Eric S. Johansson wrote:
> Steven D'Aprano wrote:
>> That assumes that every word is all caps. In practice, for real-life 
>> Python code, I've tripled the vocal load of perhaps one percent of your 
>> utterances, which cuts your productivity by 2%.
>>
>> If you have 10000 words in you per day, and one percent get wrapped with 
>> a leading and trailing "capslock", you have:
>>
>> 9900 regular words plus 100 constants
>>
>> versus
>>
>> 9700 regular words plus 100 constants plus 200 by capslock.
>>
>> Your productivity goes down by 200 words out of 10,000, or two percent.
> 
> oh I wish it was so simple. I would absolutely you if it was that simple the
> real world. Somehow, I fear that you wouldn't understand unless you sat next to
> me and watch me try to write code to  a variety of standards.
> 
> In practice, my experience says that with a really good  speech driven
> environment for programming, IT, vocal load probably by a quarter to a half and
> be more compliant with current fashion for naming.

I've tried (Windows') speech recognition some time before, and I know
it's one heck of a mess trying to type anything with it. I have a fully
working hand, so I don't actually need a voice recognition, but I
remember trying to write a single (not code) paragraph solely by
recognition. It took me over an hour correcting all those mistakes and
it really starts to gets into the nerves after the first sentence. I did
a little victory dance, after doing the first paragraph.

I know they gets better with time as they learn our speech pattern and
we learn how to pronounce the way the voice recognition expects. But one
thing I can't imagine is using voice recognition for writing code
(heck... that'll be a nightmare inside a nightmare)

>>>>> Heck, have you ever noticed how most Python smart editors can't even
>>>>> indent properly according to local contexts. Emacs is the only one and
>>>>> even that one sometimes fails
>>>> I use kwrite for editing, and I can't say I've ever noticed a failure.
>>> okay, it fails from a speech recognition user perspective. Put the
>>> cursor on the line and hit the tab key. Insert spaces/tabs in the line
>>> of text. Not good for speech recognition. If  mess of indentation and
>>> hit the tab key, it doesn't automatically indent to the right location.
>>> I'll be damned if I'm in the sit there speaking
>>> "tabkeytabkeytabkeytabkeytabkey" because the error should take care of
>>> it for me and save my voice. Like I said, Emacs does it correctly and
>>> nobody else does as far as I can tell.
>> I don't understand what you're describing.
>>
>> If you set kwrite to use "Python style" indent mode, then starting a new 
>> line will automatically indent to either the current indent level, or one 
>> extra indent level if the line ends with a colon. You shouldn't need to 
>> indent forward more than one level at a time when writing Python code, 
>> although you will need to dedent multiple levels on occasion.
> 
> I recognize your confusion. It's very common when describing this problem. If I
> had some way of making a movie of what  and describing, obviously be more clear.
> I'll see if I can make a movie with my camera that demonstrates the problem.  It
> probably won't happen fast but, what I tried your editor, it failed   with a
> trivial effort.  I think I just hit the tab key multiple times in different
> places on the line. In all cases it did the wrong thing. For me, the right thing
> is to force the line to the right indentation based on the previous line to
> matter how may times you get the tab key or where you are on that line when you
> hit the tab key. I could be in the middle of the line, the end of line, start a
> line, the start of the string and if I hit a tab key, that line should go to
> exactly the right place stayed there no matter how me more times I typed a tab key.
> 
> But this might be what you're getting confused. What I'm really asking for is
> the ability to say "force indent" and have the line indent exactly correctly
> based on context. It doesn't have to be the tab key. The tab key is the method
> of convenience.

Maybe we need an editor that could sort of understand something like:
"constant red"
and apply the appropriate code-sensitive convention transformation (in
python it'll be RED)
"class foo inheriting object"
and typed "class Foo(object):\n\t"
"indent", "dedent"
put a tab or delete a tab (or softtab)

but for all those, we're going to need a specialized text editor or
perhaps a context-sensitive voice recognition software. The simplest
solution would be a vim plugin or emacs mode that is specially tailored
to recognize these commands and apply the appropriate transformations
depending on the contexts.

>> I've already said it's your right to reject the convention for your own 
>> code. Go right ahead. This is only a problem if you're editing other 
>> people's code which is using uppercase constants.
> 
> exactly. If I'm unable to comply with local conventions, I cannot work within an
> organization and be an active member of the team. This is one example of what I
> mean by unintentional discriminatory effects of a given decision.  rhetorical
> devices aside, I think the right way to deal with accessibility issues and
> decisions leading to discrimination is to make the appropriate tools if possible
> for the individual. But I'm sure that would be a very long discussion we would
> have over a couple of beers.

Personally, I think it'd be very difficult to try to change conventions
that were made for a job that requires so much typing. In programming,
typing is almost a requirement. I'm aware people will still try to
insist on doing things they love the most no matter what happens, but I
still think if the disabled want to program, they're the one that need
to adjust their work flow and definitely with the current voice
recognition technology, they really need better tools.

>> Do you wish to raise the profile of disabled programmers?
> 
> yes. Not exactly sure of the best way but I would like to do that through
> providing tools enabling them to participate on equal footing with not yet
> disabled programmers.  I really don't like saying "take pity on the poor
> programmers with broken hands." I'd rather say "you need talent? Here's a pool
> you have previously thrown away but they can now generate code faster than the
> keyboard users.

Stephen Hawking didn't stop with his experiments when his whole body
can't move. I agree that disabilities shouldn't stop people from
programming, which is mostly the head's job. I think if we can make
voice recognition faster and easier than typing (like in those sci-fi
movies), disabled or not we will all benefit from it. Maybe some day, we
all, disabled or not, might code with voice recognition and keyboard
will be considered obsolete.


From lie.1296 at gmail.com  Thu Jul  2 09:40:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 13:40:49 GMT
Subject: pep 8 constants
In-Reply-To: <mailman.2392.1246375713.8015.python-list@python.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>	<4A48E307.50804@harvee.org>
	<4A49E232.6090101@tim.thechases.com>
	<mailman.2392.1246375713.8015.python-list@python.org>
Message-ID: <BN23m.2219$ze1.1708@news-server.bigpond.net.au>

Eric S. Johansson wrote:

> I've been working with speech recognition for 15 years. I've written something
> on the order of 10,000 lines of Python code both as open source and private
> projects. I've tried it least two dozen editors and they all fail miserably
> because they're focused on keyboard use (but understandable) I get good
> recognition accuracy because I train the system and then I let it train me.
>> For coding, you might want to investigate a tool like Dasher[1] which
>> offers an alternate form of input.  It allows for custom
>> vocabularies/keymaps if you need, as well as more precise specification
>> of a full keyboard (caps vs. mixed-case, specific punctuation
>> characters, etc).  The predictive entry should be smart enough to pick
>> up previously entered constants/terms saving you entry speed.  It can
>> also be driven by a wide variety of pointing devices (mouse, trackball,
>> touchpad, head-tracker, gyro-input, etc).
> 
> I've tried it, it's quite promising but my hands term are sufficiently that I
> can't target accurately. This is a problem for me with mice as well. Maybe these
> tiny little spit dot icons and webpages drive me insane because it takes me two
> or three tries to put the right spot.

You might want to try eye-ball tracking device. Dashers are designed for
that as well. You won't need to use your hand to type with it.


From nils at ccsg.de  Thu Jul  2 09:51:25 2009
From: nils at ccsg.de (=?ISO-8859-1?Q?Nils_R=FCttershoff?=)
Date: Thu, 02 Jul 2009 15:51:25 +0200
Subject: Spam? Re: whizBase vs. Python
In-Reply-To: <0bc58d9a-37cf-4e09-a28f-5edb0489ea30@h8g2000yqm.googlegroups.com>
References: <620ad7d3-6c1a-4869-b844-1951095bb92c@g19g2000yql.googlegroups.com>	<Ms%1m.1712$8r.1372@nlpi064.nbdc.sbc.com>
	<0bc58d9a-37cf-4e09-a28f-5edb0489ea30@h8g2000yqm.googlegroups.com>
Message-ID: <4A4CBB5D.9070104@ccsg.de>

NurAzije wrote:
> On Jun 29, 11:04 am, Tim Harig <user... at ilthio.net> wrote:
>   
>> On 2009-06-29, NurAzije <nuraz... at gmail.com> wrote:
>>
>>     
>>> Hi,
>>> I am working on a study and I need expert opinion, I did not work with
>>> Python before, can anyone help me with a comparison betweenWhizBase
>>> (www.whizbase.com) and Python please.
>>>       
>> Given posts like:http://groups.google.com/group/Server-side-programing/browse_thread/t...
>> is this just thinly veiled spam?  The domain and the posting IP address are
>> both out of Sarajevo, Bosnia.
>>
>> Obviously you alreadly know your product is nothing but a database
>> macro processor.  Python is a dynamic programming language and therefore
>> far more capable.
>>
>> Your product is proprietary with less capability while Python is free and
>> powerful.
>>     
>
> Hi Tim,
> I am not a spammer, WhizBase is from Sarajevo and I am from Sarajevo,
> for that it is interesting for me.
>
> regards,
> Ashraf Gheith
>   
Hi Ashraf,

hm... but it seems you know WhizBase very well, here a blog
(http://whizbase-scripting-language.blogspot.com/) of you with very
detailed information about WhizBase. Why you are asking nearly any
programming list/group about the difference?:

http://www.highdots.com/forums/javascript-discussion-multi-lingual/whizbase-vs-javascript-281242.html
http://groups.google.com/group/alt.comp.lang.learn.c-c++/browse_thread/thread/a7a47adb904319ad
http://groups.google.com/group/comp.lang.lisp/browse_thread/thread/9dfa76ad94d75168/01a999b7b8638621?lnk=raot
http://www.mail-archive.com/dotnetdevelopment at googlegroups.com/msg07381.html

Hm here the main blog:
http://whizbase.blogspot.com/

There is a second contributer Faik Djikic and Whizbase is from a company
called "Djikic Software Development"......

What's the Topic of your study? Whizbase compared to other languages?
Why Whizbase? Is your study public and if so were we could read it? ;)

Regards, Nils
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/6312fbdc/attachment-0001.html>

From jcd at sdf.lonestar.org  Thu Jul  2 10:15:49 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Thu, 02 Jul 2009 10:15:49 -0400
Subject: Idioms and Anti-Idioms Question
In-Reply-To: <h2erl2$h7l$1@lust.ihug.co.nz>
References: <mailman.1932.1245644100.8015.python-list@python.org>
	<H0F%l.20231$y61.5030@news-server.bigpond.net.au>
	<slrnh402pc.deb.peter@box8.pjb.com.au>
	<mailman.2018.1245772229.8015.python-list@python.org>
	<h2erl2$h7l$1@lust.ihug.co.nz>
Message-ID: <1246544149.5775.0.camel@aalcdl07>

On Wed, 2009-07-01 at 17:19 +1200, Lawrence D'Oliveiro wrote:
> In message <mailman.2018.1245772229.8015.python-list at python.org>, J. Cliff 
> Dyer wrote:
> 
> > If the lines got separated, a leading + could disappear into its line
> > without any errors showing up.  A trailing + would raise a syntax error.
> 
> Unless, of course, it was moved onto the previous line as part of whatever 
> caused the separation of the lines. How would you guard against that?
> 

Can you give an example of what you mean?



From gil.shinar at gmail.com  Thu Jul  2 10:17:58 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Thu, 2 Jul 2009 07:17:58 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
	<5efbbfef-6dde-4244-ab6c-6d30be5ac0cc@x17g2000yqd.googlegroups.com> 
	<mailman.2442.1246489542.8015.python-list@python.org>
Message-ID: <20e625ef-8fa2-4ed5-9ae4-a5b3fa2b1019@o6g2000yqj.googlegroups.com>

On Jul 2, 1:08?am, s... at pobox.com wrote:
> ? ? Gil> There's no such group as python-sybase :-(
>
> http://sourceforge.net/mailarchive/forum.php?forum_name=python-sybase...
>
> S

Thanks :-)


From gil.shinar at gmail.com  Thu Jul  2 10:19:36 2009
From: gil.shinar at gmail.com (eranlevi)
Date: Thu, 2 Jul 2009 07:19:36 -0700 (PDT)
Subject: Timeout when connecting to sybase DBS
References: <2dc9f53f-acc0-44cd-9b5b-7062ab401030@a38g2000yqc.googlegroups.com>
	<mailman.2400.1246380530.8015.python-list@python.org>
	<794c83d9-9a53-4e03-89d0-1c369cdc70ec@c36g2000yqn.googlegroups.com>
	<mailman.2441.1246489542.8015.python-list@python.org>
Message-ID: <c05cc9db-36de-422b-b639-fff9050075a3@h18g2000yqj.googlegroups.com>

On Jul 2, 1:07?am, s... at pobox.com wrote:
> ? ? Gil> Are you saying, that when you trying to connect to a sybase DBS
> ? ? Gil> server and the DBS or the server is down, you get an error after a
> ? ? Gil> few seconds and not after a few minutes?
>
> Yes, though thankfully our server tends to almost always be up.
>
> ? ? Gil> Which python version are you using?
>
> We're still running 2.4.5 at work and have a slightly hacked very old
> version of the python-sybase package (0.36).
>
> --
> Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> ? ? when i wake up with a heart rate below 40, i head right for the espresso
> ? ? machine. -- chaos @ forums.usms.org

That is really strange :-(
I'll ask in the python-sybase group

Thanks


From nobody at nowhere.com  Thu Jul  2 10:23:51 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 02 Jul 2009 15:23:51 +0100
Subject: PEP368 and pixeliterators
References: <mailman.2475.1246523526.8015.python-list@python.org>
Message-ID: <pan.2009.07.02.14.23.50.656000@nowhere.com>

On Thu, 02 Jul 2009 10:32:04 +0200, Joachim Str?mbergson wrote:

> I just read the PEP368 and really liked the proposed idea, sound like a
> great battery addition to include in the std lib:
> 
> http://www.python.org/dev/peps/pep-0368/

Unfortunately, it's too simplistic, meaning that most of the existing
image formats used by the various GUI toolkits (and OpenGL) will need to
be retained.

Obvious omissions include support for arbitrary numbers of bits per
component (e.g. R5G5B5A1), component, pixel and row strides (padding),
mixing packed and planar components (e.g. packed RGB with a separate alpha
plane), and storage orientation (top-to-bottom or bottom-to-top).

Ideally, an Image should be able to use any sane storage format, so that
you don't have to keep converting the Image to an application-specific
format.

NumPy's arrays would probably be a good model here. Essentially, each
component would have a base pointer plus horizontal and vertical strides
measured in bits.

The strides wouldn't necessarily be the same for all components (allowing
for an R8G8B8 plane with a 3-byte stride plus a distinct A8 plane with a
1-byte stride), vertical stride wouldn't necessarily be greater than
horizontal stride (allowing transposition), strides could be negative
(allowing mirroring), and could be less than a byte (allowing e.g. a 1-bpp
alpha channel, planar 4-bpp data, 12-bpp greyscale, etc).

AFAICT, this would allow all common image storage formats to be
represented. The most common exception is 8-bit RGB data using a 6x6x6
colour cube, but that's not common enough to be worth the added complexity.

The interface should also be flexible enough to allow an Image to be a
"proxy" for a non-local image (e.g. one held in video RAM or in the X
server). You wouldn't be able to get a buffer for the image data, but you
should at least be able to obtain the dimensions and format of such
images, and ideally copy the data (or rectangular subregions) to/from a
local image.



From hv at tbz-pariv.de  Thu Jul  2 10:50:34 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Thu, 02 Jul 2009 16:50:34 +0200
Subject: logging of strings with broken encoding
Message-ID: <7b3vpqF20nct6U1@mid.individual.net>

Hi,

I have bug in my code, which results in the same error has this one:

https://bugs.launchpad.net/bzr/+bug/295653
{{{
Traceback (most recent call last):
  File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
    self.stream.write(fs % msg.encode("UTF-8"))
  ..
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8: ordinal not in range(128)
}}}

I run Python 2.6. In SVN the code is the same (StreamHandler ... def emit...):
http://svn.python.org/view/python/branches/release26-maint/Lib/logging/__init__.py?revision=72507&view=markup

I think msg.encode("UTF-8", 'backslashreplace') would be better here.

What do you think?

Should I fill a bugreport?

  Thomas


-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From vertespain at gmail.com  Thu Jul  2 11:09:43 2009
From: vertespain at gmail.com (masher)
Date: Thu, 2 Jul 2009 08:09:43 -0700 (PDT)
Subject: multiprocessing: pool with blocking queue
Message-ID: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>

Hi,

I am trying to implement a multiprocessing pool that assigns tasks
from a blocking queue. My situation is a pretty classic producer/
consumer conundrum, where the producer can produce much faster than
the consumers can consume. The wrinkle in the story is that the
producer produces objects that consume large amounts of memory, so I
would like the queue to block when it reaches, say, twice the number
of tasks as there are processes in the pool, so that I don't devour my
RAM. I have been able to implement this one way, but I am somewhat
displeased with the result. Code speaks louder than words, so here is
a brief example of the technique I am using, followed by an
explanation of why I am unhappy with it:

===
#!/usr/bin/env python3

import time
import random
from multiprocessing import Pool, Queue, M

def procfunc(queue):
    time.sleep(random.random() * 2)
    return queue.get()*2

def printrange(n):
    for i in range(n):
        print("generated " + str(i))
        yield i

if __name__ == "__main__":
    sm = Manager()
    pool = Pool()
    queuelen = len(pool._pool) * 2
    queue = sm.Queue(queuelen)
    for i in printrange(100):
        queue.put(i)
        pool.apply_async(procfunc, (queue,), callback=print)
    pool.close()
    pool.join()
===

The reason I am unhappy with this trick is that if you examine the
source code of pool.py, you will note that the class Pool already uses
an internal queue, "_taskqueue" from which the tasks are assigned to
processes in the pool.

Particularly:
def __init__(self, processes=None, initializer=None, initargs=()):
    self._setup_queues()
    self._taskqueue = queue.Queue()
...snip

It seems to me that if I could only subclass and do
  queuelen = len(pool._pool) * 2
  self._taskqueue = queue.Queue(queuelen)

later in the constructor, once the pool length has been established, I
would have a much more elegant, transparent solution to the problem.

Unfortunately, the design of the Pool class is such that actually
implementing this solution would be very hackish and inelegant. If
only, say, _setup_queues() were called after the _taskqueue
assignment, then I could override it.

My questions, then, is: Is there a more elegant/pythonic way of doing
what I am trying to do with the current Pool class?

If the verdict is no, I'll be happy to file a bug report.


From dns4 at cornell.edu  Thu Jul  2 11:09:58 2009
From: dns4 at cornell.edu (David Smith)
Date: Thu, 02 Jul 2009 11:09:58 -0400
Subject: logging of strings with broken encoding
In-Reply-To: <7b3vpqF20nct6U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <h2iik4$ltq$1@ruby.cit.cornell.edu>

Thomas Guettler wrote:
> Hi,
> 
> I have bug in my code, which results in the same error has this one:
> 
> https://bugs.launchpad.net/bzr/+bug/295653
> {{{
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
>     self.stream.write(fs % msg.encode("UTF-8"))
>   ..
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8: ordinal not in range(128)
> }}}
> 
> I run Python 2.6. In SVN the code is the same (StreamHandler ... def emit...):
> http://svn.python.org/view/python/branches/release26-maint/Lib/logging/__init__.py?revision=72507&view=markup
> 
> I think msg.encode("UTF-8", 'backslashreplace') would be better here.
> 
> What do you think?
> 
> Should I fill a bugreport?
> 
>   Thomas
> 
> 

I think you have to decode it first using the strings original encoding
whether that be cp1252 or mac-roman or any of the other 8-bit encodings.
 Once that's done, you can encode in UTF-8

--David


From __peter__ at web.de  Thu Jul  2 11:16:29 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 02 Jul 2009 17:16:29 +0200
Subject: logging of strings with broken encoding
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <h2ij02$kor$01$1@news.t-online.com>

Thomas Guettler wrote:

> I have bug in my code, which results in the same error has this one:
> 
> https://bugs.launchpad.net/bzr/+bug/295653
> {{{
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
>     self.stream.write(fs % msg.encode("UTF-8"))
>   ..
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8:
> ordinal not in range(128) }}}
> 
> I run Python 2.6. In SVN the code is the same (StreamHandler ... def
> emit...):
> http://svn.python.org/view/python/branches/release26-
maint/Lib/logging/__init__.py?revision=72507&view=markup
> 
> I think msg.encode("UTF-8", 'backslashreplace') would be better here.
> 
> What do you think?

That won't help. It's a *decoding* error. You are feeding it a non-ascii 
byte string.

Peter



From wells at submute.net  Thu Jul  2 11:32:40 2009
From: wells at submute.net (Wells Oliver)
Date: Thu, 2 Jul 2009 10:32:40 -0500
Subject: MySQLdb and ordering of column names in list returned by keys() w/ a 
	DictCursor
Message-ID: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>

Is there some kind of mysterious logic to how the the columns are ordered
when executing the following:

sql = "SELECT player_id, SUM(K) AS K, SUM(IP) AS IP, SUM(ER) AS ER, SUM(HR)
AS HR, SUM(H) AS H, SUM(BB) AS BB, Teams.league FROM Pitching INNER JOIN
Teams ON Pitching.team = Teams.team_id WHERE Date BETWEEN '%s' AND '%s'
GROUP BY player_id" % (start, date)
cursor.execute(sql)

for row in cursor.fetchall():
    print row.keys()

What I get is:

['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']

Neither alphabetical nor the order in which they were specified in the query
nor... any seeming order I can suss out. Any ideas? Thanks!

(cursor being a MySQLdb.cursors.DictCursor object.)

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/4fab3fa9/attachment-0001.html>

From python.list at tim.thechases.com  Thu Jul  2 11:48:18 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 02 Jul 2009 10:48:18 -0500
Subject: MySQLdb and ordering of column names in list returned by keys()
	w/ a    DictCursor
In-Reply-To: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
Message-ID: <4A4CD6C2.2030103@tim.thechases.com>

> sql = "SELECT player_id, SUM(K) AS K, SUM(IP) AS IP, SUM(ER) AS ER, SUM(HR)
> AS HR, SUM(H) AS H, SUM(BB) AS BB, Teams.league FROM Pitching INNER JOIN
> Teams ON Pitching.team = Teams.team_id WHERE Date BETWEEN '%s' AND '%s'
> GROUP BY player_id" % (start, date)
> cursor.execute(sql)
> 
> for row in cursor.fetchall():
>     print row.keys()
> 
> What I get is:
> 
> ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
> 
> Neither alphabetical nor the order in which they were specified in the query
> nor... any seeming order I can suss out. Any ideas? Thanks!
> 
> (cursor being a MySQLdb.cursors.DictCursor object.)

My guess is you're experiencing the fact that dicts are unordered 
by nature which allows it to return in any order it likes 
(usually per the internal representation/storage).

-tkc





From lie.1296 at gmail.com  Thu Jul  2 11:49:46 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 15:49:46 GMT
Subject: logging of strings with broken encoding
In-Reply-To: <7b3vpqF20nct6U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <uG43m.2224$ze1.2217@news-server.bigpond.net.au>

Thomas Guettler wrote:
> Hi,
> 
> I have bug in my code, which results in the same error has this one:
> 
> https://bugs.launchpad.net/bzr/+bug/295653
> {{{
> Traceback (most recent call last):
>   File "/usr/lib/python2.6/logging/__init__.py", line 765, in emit
>     self.stream.write(fs % msg.encode("UTF-8"))
>   ..
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 8: ordinal not in range(128)
> }}}

What's the encoding of self.stream? Is it sys.stdout/sys.stderr or a
file object?


From hv at tbz-pariv.de  Thu Jul  2 11:53:14 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Thu, 02 Jul 2009 17:53:14 +0200
Subject: logging of strings with broken encoding
In-Reply-To: <7b3vpqF20nct6U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
Message-ID: <7b43faF21l89hU1@mid.individual.net>

My quick fix is this:

class MyFormatter(logging.Formatter):
    def format(self, record):
        msg=logging.Formatter.format(self, record)
        if isinstance(msg, str):
            msg=msg.decode('utf8', 'replace')
        return msg

But I still think handling of non-ascii byte strings should be better.
A broken logging message is better than none.

And, if there is a UnicodeError, handleError() should not send the message
to sys.stderr, but it should use emit() of the current handler.

In my case sys.stderr gets discarded. Its very hard to debug, if you don't
see any logging messages.

  Thomas

Thomas Guettler schrieb:
> Hi,
> 
> I have bug in my code, which results in the same error has this one:
>  ...

-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From wells at submute.net  Thu Jul  2 11:57:05 2009
From: wells at submute.net (Wells Oliver)
Date: Thu, 2 Jul 2009 10:57:05 -0500
Subject: MySQLdb and ordering of column names in list returned by keys() 
	w/ a DictCursor
In-Reply-To: <4A4CD6C2.2030103@tim.thechases.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
	<4A4CD6C2.2030103@tim.thechases.com>
Message-ID: <3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com>

Will this order at least be the same for that same query every time the
script is executed?

On Thu, Jul 2, 2009 at 10:48 AM, Tim Chase <python.list at tim.thechases.com>wrote:

> sql = "SELECT player_id, SUM(K) AS K, SUM(IP) AS IP, SUM(ER) AS ER, SUM(HR)
>> AS HR, SUM(H) AS H, SUM(BB) AS BB, Teams.league FROM Pitching INNER JOIN
>> Teams ON Pitching.team = Teams.team_id WHERE Date BETWEEN '%s' AND '%s'
>> GROUP BY player_id" % (start, date)
>> cursor.execute(sql)
>>
>> for row in cursor.fetchall():
>>    print row.keys()
>>
>> What I get is:
>>
>> ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
>>
>> Neither alphabetical nor the order in which they were specified in the
>> query
>> nor... any seeming order I can suss out. Any ideas? Thanks!
>>
>> (cursor being a MySQLdb.cursors.DictCursor object.)
>>
>
> My guess is you're experiencing the fact that dicts are unordered by nature
> which allows it to return in any order it likes (usually per the internal
> representation/storage).
>
> -tkc
>
>
>
>


-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/44e67377/attachment-0001.html>

From james at agentultra.com  Thu Jul  2 12:06:58 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 02 Jul 2009 12:06:58 -0400
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
Message-ID: <851vozf4rh.fsf@agentultra.com>

masher <vertespain at gmail.com> writes:

> My questions, then, is: Is there a more elegant/pythonic way of doing
> what I am trying to do with the current Pool class?

Forgive me, I may not fully understand what you are trying to do here
(I've never really used multiprocessing all that much)...

But couldn't you just assign your own Queue object to the Pool instance?


From robert.kern at gmail.com  Thu Jul  2 12:23:40 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 02 Jul 2009 11:23:40 -0500
Subject: deleting certain entries in numpy array
In-Reply-To: <4a4c7fd9$1@news.fhg.de>
References: <4a4b7763$1@news.fhg.de>	<mailman.2440.1246489510.8015.python-list@python.org>
	<4a4c7fd9$1@news.fhg.de>
Message-ID: <h2imud$gf8$1@ger.gmane.org>

On 2009-07-02 04:40, Sebastian Schabe wrote:
> Robert Kern schrieb:

>  > You will want to ask numpy questions on the numpy mailing list.
>  >
>  > http://www.scipy.org/Mailing_Lists
>  >
>
> I ever thought news-groups are the right way for questions like this.
> And the mailing list page just confuses me, but I'm trying to get used
> to it.

You may want to try GMane, then:

   http://dir.gmane.org/gmane.comp.python.numeric.general

It's how I read this list, for instance.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From vertespain at gmail.com  Thu Jul  2 12:25:54 2009
From: vertespain at gmail.com (masher)
Date: Thu, 2 Jul 2009 09:25:54 -0700 (PDT)
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
	<851vozf4rh.fsf@agentultra.com>
Message-ID: <cd3362ac-e189-4dea-93d5-06db3aaafd29@c36g2000yqn.googlegroups.com>

On Jul 2, 12:06?pm, J Kenneth King <ja... at agentultra.com> wrote:
> masher <vertesp... at gmail.com> writes:
> > My questions, then, is: Is there a more elegant/pythonic way of doing
> > what I am trying to do with the current Pool class?
>
> Forgive me, I may not fully understand what you are trying to do here
> (I've never really used multiprocessing all that much)...
>
> But couldn't you just assign your own Queue object to the Pool instance?

That's basically my question. It does not appear as though there is
any straightforward way of doing this because of the design of Pool's
__init__ method, which passes _taskqueue to several functions. Hence,
even if I were to reassign _taskqueue after __init__, that wouldn't
change anything.


From ethan at stoneleaf.us  Thu Jul  2 12:38:56 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 02 Jul 2009 09:38:56 -0700
Subject: regex question on .findall and \b
Message-ID: <4A4CE2A0.5040407@stoneleaf.us>

Greetings!

My closest to successfull attempt:

Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel)]
Type "copyright", "credits" or "license" for more information.

IPython 0.9.1 -- An enhanced Interactive Python.

   In [161]: re.findall('\d+','this is test a3 attempt 79')
   Out[161]: ['3', '79']

What I really want in just the 79, as a3 is not a decimal number, but 
when I add the \b word boundaries I get:

   In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
   Out[162]: []

What am I missing?

~Ethan~


From tim.wintle at teamrubber.com  Thu Jul  2 12:49:48 2009
From: tim.wintle at teamrubber.com (Tim Wintle)
Date: Thu, 02 Jul 2009 17:49:48 +0100
Subject: Dict ordering [was: Re: MySQLdb and ordering of column names in
	list returned by keys() w/ a  DictCursor]
In-Reply-To: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>
Message-ID: <1246553388.18497.5.camel@tim-laptop>

On Thu, 2009-07-02 at 10:32 -0500, Wells Oliver wrote:
> for row in cursor.fetchall():
>     print row.keys()
> 
> What I get is:
> 
> ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
> 
> Neither alphabetical nor the order in which they were specified in the
> query nor... any seeming order I can suss out. Any ideas? Thanks!

keys in a dict are not guaranteed to be in any specific order. It's not
specific to the MySQLdb cursor.

IIRC it's related to the hashes of the keys (but obviously not in
strictly increasing order). You definitely shouldn't rely on the
ordering (hence the need for an OrderedDict.

e.g. 

>>> a = ['league', 'BB', 'HR', 'IP', 'K', 'H', 'player_id', 'ER']
>>> for s in a:
...   print hash(s)
... 
-3369365635700083487
8448050754076166
9216055368083080
9344056137084361
9600028874
9216027721
1844482854915224472
8832053061079775



From python.list at tim.thechases.com  Thu Jul  2 12:50:09 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 02 Jul 2009 11:50:09 -0500
Subject: MySQLdb and ordering of column names in list returned by keys()
	w/ a DictCursor
In-Reply-To: <3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com>	
	<4A4CD6C2.2030103@tim.thechases.com>
	<3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com>
Message-ID: <4A4CE541.9030308@tim.thechases.com>

> Will this order at least be the same for that same query every time the
> script is executed?

I wouldn't count on it.  The order is only defined for the one 
iteration (result of the keys() call).  If the order matters, I'd 
suggest a double-dispatch with a non-dict (regular/default) query 
result, something like

   header_map = dict(
     (desc[0], i)
     for i,desc in enumerate(cursor.description)
     )
   for row in cursor.fetchall():
     print row[header_map['league']]

If you have a lot of fields, I often use a closure to simplify 
the coding:

   for row in cursor.fetchall():
     item = lambda s: row[headermap[s]]
     print item('league')
     print item('BB')
     print item('player_id')

That way, the row stays in order, if you need it that way:

   league, bb, hr, ip, k, h, id, er = row

-tkc





From stefan_ml at behnel.de  Thu Jul  2 13:01:37 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Thu, 02 Jul 2009 19:01:37 +0200
Subject: logging of strings with broken encoding
In-Reply-To: <7b43faF21l89hU1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
Message-ID: <4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>

Thomas Guettler wrote:
> My quick fix is this:
> 
> class MyFormatter(logging.Formatter):
>     def format(self, record):
>         msg=logging.Formatter.format(self, record)
>         if isinstance(msg, str):
>             msg=msg.decode('utf8', 'replace')
>         return msg
> 
> But I still think handling of non-ascii byte strings should be better.
> A broken logging message is better than none.

Erm, may I note that this is not a problem in the logging library but in
the code that uses it? How should the logging library know what you meant
by passing that byte string in the first place? And where is the difference
between accidentally passing a byte string and accidentally passing another
non-printable object? Handling this "better" may simply hide the bugs in
your code, I don't find that's any "better" at all.

Anyway, this has been fixed in Py3.

Stefan


From ethan at stoneleaf.us  Thu Jul  2 13:12:32 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 02 Jul 2009 10:12:32 -0700
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A4CEA80.4050803@stoneleaf.us>

Ethan Furman wrote:
> Greetings!
> 
> My closest to successfull attempt:
> 
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit 
> (Intel)]
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.9.1 -- An enhanced Interactive Python.
> 
>   In [161]: re.findall('\d+','this is test a3 attempt 79')
>   Out[161]: ['3', '79']
> 
> What I really want in just the 79, as a3 is not a decimal number, but 
> when I add the \b word boundaries I get:
> 
>   In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
>   Out[162]: []
> 
> What am I missing?
> 
> ~Ethan~


ARGH!!

Okay, I need two \\ so I'm not trying to match a backspace.  I knew 
(okay, hoped ;) I would figure it out once I posted the question and 
moved on.

*sheepish grin*



From lie.1296 at gmail.com  Thu Jul  2 13:14:34 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 17:14:34 GMT
Subject: logging of strings with broken encoding
In-Reply-To: <7b43faF21l89hU1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
Message-ID: <_V53m.2227$ze1.167@news-server.bigpond.net.au>

Thomas Guettler wrote:
> My quick fix is this:
> 
> class MyFormatter(logging.Formatter):
>     def format(self, record):
>         msg=logging.Formatter.format(self, record)
>         if isinstance(msg, str):
>             msg=msg.decode('utf8', 'replace')
>         return msg
> 
> But I still think handling of non-ascii byte strings should be better.
> A broken logging message is better than none.
> 

The problem is, python 2.x assumed the default encoding of `ascii`
whenever you don't explicitly mention the encoding, and your code
apparently broke with that assumption. I haven't looked at your code,
but others have suggested that you've fed the logging module with
non-ascii byte strings. The logging module can only work with 1) unicode
string, 2) ascii-encoded byte string

If you want a quick fix, you may be able to get away with repr()-ing
your log texts. A proper fix, however, is to pass a unicode string to
the logging module instead.

>>> logging.warn('?') # or logging.warn('\xd1\x8b')
Traceback (most recent call last):
  File "/usr/lib64/python2.6/logging/__init__.py", line 773, in emit
    stream.write(fs % msg.encode("UTF-8"))
UnicodeDecodeError: 'ascii' codec can't decode byte 0xd1 in position 13:
ordinal not in range(128)
>>> logging.warn(repr('?'))
WARNING:root:'\xd1\x8b'
>>> logging.warn(u'?')
WARNING:root:?


From python.list at tim.thechases.com  Thu Jul  2 13:17:22 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 02 Jul 2009 12:17:22 -0500
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A4CEBA2.9040303@tim.thechases.com>

Ethan Furman wrote:
> Greetings!
> 
> My closest to successfull attempt:
> 
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel)]
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.9.1 -- An enhanced Interactive Python.
> 
>    In [161]: re.findall('\d+','this is test a3 attempt 79')
>    Out[161]: ['3', '79']
> 
> What I really want in just the 79, as a3 is not a decimal number, but 
> when I add the \b word boundaries I get:
> 
>    In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
>    Out[162]: []
> 
> What am I missing?

The sneaky detail that the regexp should be in a raw string 
(always a good practice), not a cooked string:

   r'\b\d+\b'

The "\d" isn't a valid character-expansion, so python leaves it 
alone.  However, I believe the "\b" is a control character, so 
your actual string ends up something like:

   >>> print repr('\b\d+\b')
   '\x08\\d+\x08'
   >>> print repr(r'\b\d+\b')
   '\\b\\d+\\b'

the first of which doesn't match your target string, as you might 
imagine.

-tkc





From lie.1296 at gmail.com  Thu Jul  2 13:18:00 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 17:18:00 GMT
Subject: invoking a method from two superclasses
In-Reply-To: <f656c6a7-46ff-45c4-b7eb-98e1378c7f30@b15g2000yqd.googlegroups.com>
References: <mailman.8861.1246401585.8014.python-list@python.org>
	<mailman.2416.1246408453.8015.python-list@python.org>
	<31fe4bef-6738-4de5-b9bb-c0dc42c695a7@o6g2000yqj.googlegroups.com>
	<f656c6a7-46ff-45c4-b7eb-98e1378c7f30@b15g2000yqd.googlegroups.com>
Message-ID: <cZ53m.2228$ze1.66@news-server.bigpond.net.au>

Carl Banks wrote:
> On Jun 30, 6:23 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
>> On Jun 30, 5:34 pm, Mitchell L Model <MLMLi... at Comcast.net> wrote:
>>
>>> Allow me to add to my previous question that certainly the superclass
>>> methods can be called explicitly without resorting to super(), e.g.:
>>>     class C(A, B):
>>>         def __init__(self):
>>>             A.__init__(self)
>>>             B.__init__(self)
>>> My question is really whether there is any way of getting around the
>>> explicit class names by using super()
>> Yes there is: just make sure that all subclasses also call super.
> 
> And by subclasses I mean base classes, of course.  ugh
> 
> 
> Carl Banks

super() is short for two things:
1) superharmful
2) superuseful


From sjoerd at acm.org  Thu Jul  2 13:18:07 2009
From: sjoerd at acm.org (Sjoerd Mullender)
Date: Thu, 02 Jul 2009 19:18:07 +0200
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A4CEBCF.9010203@acm.org>

On 2009-07-02 18:38, Ethan Furman wrote:
> Greetings!
>
> My closest to successfull attempt:
>
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit
> (Intel)]
> Type "copyright", "credits" or "license" for more information.
>
> IPython 0.9.1 -- An enhanced Interactive Python.
>
> In [161]: re.findall('\d+','this is test a3 attempt 79')
> Out[161]: ['3', '79']
>
> What I really want in just the 79, as a3 is not a decimal number, but
> when I add the \b word boundaries I get:
>
> In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
> Out[162]: []
>
> What am I missing?
>
> ~Ethan~

Try this:
 >>> re.findall(r'\b\d+\b','this is test a3 attempt 79')
['79']

The \b is a backspace, by using raw strings you get an actual backslash 
and b.

-- 
Sjoerd Mullender


From philip at semanchuk.com  Thu Jul  2 13:22:53 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 2 Jul 2009 13:22:53 -0400
Subject: dealloc function in python extend c module
In-Reply-To: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
References: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
Message-ID: <8599A253-D2C9-4EE4-AF4F-AEF658BA2033@semanchuk.com>


On Jul 2, 2009, at 2:11 AM, Shen, Yu-Teh wrote:

> I create my extend type something like http://www.python.org/doc/current/extending/newtypes.html 
> .
> And my type has a member which is a pointer point to my allocate
> memory ( no ref count).
> ex:
> ---------------------------------------------------
> typedef struct {
>    PyObject_HEAD
>    /* Type-specific fields go here. */
>    mytype *p;
> } noddy_NoddyObject;
>
> And i write dealloc function like this:
> ---------------------------------------------------
> static void
> Noddy_dealloc(Noddy* self)
> {
>    delete p;
>    self->ob_type->tp_free((PyObject*)self);
> }
>
> And I found it's strange that it didn't call dealloc when there is no
> reference.
>
> ex:
> a = Noddy()
> b = a
> del a
> del b
> # i think there is no ref to the object, and it should call dealloc
> but it didn't call!!!
>
> could anyone tell me what happened?


Hi Shen,
I'm no expert on Python memory management, but since no once else has  
answered your question I'll tell you what I *think* is happening.

Python doesn't delete objects as soon as they're dereferenced. It  
merely marks them as safe for garbage collection (GC). If GC never  
happens (and it might not in a small test program), your dealloc  
function won't run.

Now some more knowledgeable person will probably correct me. =)

You can control the garbage collector manually with Python's gc  
module. You will probably never want to control the garbage collector  
manually in ordinary programs, but it can be useful for testing.


Hope this helps
Philip



From sajmikins at gmail.com  Thu Jul  2 13:23:55 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 10:23:55 -0700 (PDT)
Subject: question of style
Message-ID: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>

Hey I was hoping to get your opinions on a sort of minor stylistic
point.
These two snippets of code are functionally identical. Which would you
use and why?
The first one is easier [for me anyway] to read and understand, but
slightly less efficient, while the second is [marginally] harder to
follow but more efficient.

## First snippet

if self.higher is self.lower is None: return
if self.lower is None: return self.higher
if self.higher is None: return self.lower

## Second snippet

if self.higher is None:
    if self.lower is None:
        return
    return self.lower
if self.lower is None:
    return self.higher

What do you think?

(One minor point: in the first snippet, the "is None" in the first
line is superfluous in the context in which it will be used, the only
time "self.lower is self.higher" will be true is when they are both
None.)


From chambon.pascal at gmail.com  Thu Jul  2 13:34:00 2009
From: chambon.pascal at gmail.com (Pascal Chambon)
Date: Thu, 02 Jul 2009 19:34:00 +0200
Subject: Direct interaction with subprocess - the curse of blocking I/O
In-Reply-To: <pan.2009.06.29.20.45.06.312000@nowhere.com>
References: <mailman.2320.1246302955.8015.python-list@python.org>
	<pan.2009.06.29.20.45.06.312000@nowhere.com>
Message-ID: <4A4CEF88.80201@gmail.com>

Thank you all for the comments

>you might want something like Expect.

Yes "Expect" deals with such things, unfortunately it's posix only (due to the PTY module requirement...); whereas I'd like to find generic ways (i.e at least windows/linux/mac recipes)

> The latter is inherently tricky (which is why C's popen() lets you connect
> to stdin or stdout but not both). You have to use either multiple threads,
> select/poll, or non-blocking I/O.
>
> If the child's output is to the console, it should presumably be the
> former, i.e. piping stdin but allowing the child to inherit stdout, in
> which case, where's the problem? Or are you piping its stdout via Python
> for the hell of it
It's well a too-way piping that I'd like to get ; but actually, even  a 
single-way piping is error-prone : if I try to send data to the child's 
stdin, and this child never wants to receive that data (for whatever 
reason), the parent thread will be forever stuck.
I can use multiple threads, but it doesn't fully solve the problem, 
because having even a single thread stuck might prevent the process from 
terminating, on some operating systems... I'd need a way to deblock I/O 
blocking threads (but even closing the pipe isn't sure to do it properly 
- the closing might be delayed by the I/O operations wating).


 >I would guess the architectural differences are so great that an attempt
 >to "do something simple" is going to involve architecture-specific code.
 >and I personally wouldn't have it any other way.  Simulating a shell
 >with hooks on its I/O should be so complicated that a "script kiddie"
 >has trouble writing a Trojan.

I'm not sure I understand the security hole there - if a script kiddie 
manages to make you execute his program, he doesn't need complex I/O 
redirections to harm you, simply destroying files randomly on your hard 
drive should fit his needs shouldn't it. :?


> > I met the issue : select() works only on windows ...
>   

>No it doesn't. It works only on sockets on Windows, on Unix/Linux it works 
>with all file descriptors <http://docs.python.org/library/select.html>.


Indeed, I mixed up my words there... >_<


 >If you are willing to have a wxPython dependency, wx.Execute handles 
non-blocking i/o with processes on all supported platforms more 
discussion of python's blocking i/o issues here:
 >  
http://groups.google.com/group/comp.lang.python/browse_thread/thread/a037349e18f99630/60886b8beb55cfbc?q=#60886b8beb55cfbc

Very interesting link, that's exactly the problem... and it seems no 
obvious solution comes out of it, except, of course, going down to the 
OS' internals...
File support is really weak in python I feel (stdio is a little 
outdated...), it'd need a complete blocking/non-blocking, 
locking/non-locking stream API straight in the stdlib...
I'm already working on locking classes, I'll explore the opportunity for 
a higher level "file" object too whenever possible (a new filesystem api 
is in progress here at europython2009, it might be the occasion).


regards,
Pascal



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/7d97340c/attachment-0001.html>

From lie.1296 at gmail.com  Thu Jul  2 13:37:01 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 02 Jul 2009 17:37:01 GMT
Subject: PEP 376
In-Reply-To: <mailman.2489.1246540523.8015.python-list@python.org>
References: <mailman.2410.1246390911.8015.python-list@python.org>		<h2ec5l$820$1@lust.ihug.co.nz>		<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>		<mailman.2422.1246418400.8015.python-list@python.org>		<h2f7jt$j33$1@south.jnrs.ja.net>	<4A4C685A.8020300@Strombergson.com>	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
Message-ID: <1f63m.2229$ze1.1410@news-server.bigpond.net.au>

Joachim Str?mbergson wrote:
> Aloha!
> 
> Tarek Ziad? wrote:
>> The prefix is a good idea but since it's just a checksum to control
>> that the file hasn't changed
>> what's wrong with using a weak hash algorithm like md5 or now sha1 ?
> 
> Because it creates a dependency to an old algorithm that should be
> deprecated. Also using MD5, even for a thing like this might make people
> belive that it is an ok algorithm to use - "Hey, it is used by the
> default install in Python, so it must be ok, right?"
> 
> If we flip the argument around: Why would you want to use MD5 instead of
> SHA-256? For the specific use case the performance will not (should not)
> be an issue.
> 
> As I wrote a few mails ago, it is time to move forward from MD5 and
> designing something in 2009 that will be around for many years that uses
> MD5 is (IMHO) a bad design decision.
> 
>> If someone wants to modify a file of a distribution he can recreate
>> the checksum as well,
>> the only secured way to prevent that would be to use gpg keys but
>> isn't that overkill for what we need ?
> 
> Actually, adding this type of security would IMHO be a good idea.
> 

Now, are we actually talking about security or checksum?

It has been known for years that MD5 is weak, weak, weak. Not just in
the recent years. But it doesn't matter since MD5 was never designed for
security, MD5 was designed to protect against random bits corruption. If
you want security, look at least to GPG. For data protection against
intentional, malicious forging, definitely MD5 is the wrong choice. But
when you just want a simple checksum to ensure that a faulty router
somewhere in the internet backbone doesn't destroying your data, MD5 is
a fine algorithm.


From duncan.booth at invalid.invalid  Thu Jul  2 13:44:34 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 2 Jul 2009 17:44:34 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <Xns9C3CBEAA880F8duncanbooth@127.0.0.1>

Simon Forman <sajmikins at gmail.com> wrote:

> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
> 
> ## First snippet
> 
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
> 
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
> 
> What do you think?
> 
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)
> 

I'd write the first one as:

    	if self.lower is None:
    	    	return self.higher
    	if self.higher is None:
    	    return self.lower

because the entire first 'if' statement is redundant.

As a matter of style however I wouldn't use the shorthand to run two 'is' 
comparisons together, I'd write that out in full if it was actually needed 
here.

Likewise in the second one:

    if self.lower is None:
        return
    return self.lower

is obviously the same as:

    	return self.lower

so apart from reversing the order of the comparisons once you've dropped 
the redundant test it is the same as the first one.


From petr.messner at gmail.com  Thu Jul  2 13:48:28 2009
From: petr.messner at gmail.com (Petr Messner)
Date: Thu, 2 Jul 2009 19:48:28 +0200
Subject: MySQLdb and ordering of column names in list returned by keys() 
	w/ a DictCursor
In-Reply-To: <4A4CE541.9030308@tim.thechases.com>
References: <3f1a902d0907020832v99c0d82o860df02cf47be4fc@mail.gmail.com> 
	<4A4CD6C2.2030103@tim.thechases.com>
	<3f1a902d0907020857m6c8790a9la329758bf1265dfc@mail.gmail.com> 
	<4A4CE541.9030308@tim.thechases.com>
Message-ID: <67c97cd90907021048u650ae97dhb6da2f34fabd971b@mail.gmail.com>

2009/7/2 Tim Chase <python.list at tim.thechases.com>:
>> Will this order at least be the same for that same query every time the
>> script is executed?
>
> I wouldn't count on it.  The order is only defined for the one iteration
> (result of the keys() call).  If the order matters, I'd suggest a
> double-dispatch with a non-dict (regular/default) query result, something
...

Dictionaries are usually designed to have the best performance when
accessing certain key, so it is not expected that dictionary items
will be in any particular order; this applies not only for Python. But
(for Python dict) you can be sure that results of items(), keys(),
values(), iteritems(), iterkeys(), and itervalues() will correspond if
called with no intervening modifications to the dictionary.

If such a functionality is needed, there is a collections.OrderedDict
that was introduced in Python 3.1; there is also an implementation for
Python 2.4 or later: http://code.activestate.com/recipes/576693/ (this
links is from "What?s New In Python 3.1")

PM


From cbc at unc.edu  Thu Jul  2 13:52:48 2009
From: cbc at unc.edu (Chris Calloway)
Date: Thu, 02 Jul 2009 13:52:48 -0400
Subject: Deadline for Toronto PyCamp Registraiton Appoaching
Message-ID: <4A4CF3F0.4020304@unc.edu>

Tomorrow (July 3) by midnight will be the last opportunity for Toronto 
PyCamp registration before the late registration period ending July 10.

PyCamp is the original Python BootCamp developed by a user group for
user groups. This year PyCamp is July 13-17 at the University of
Toronto, sponsored by the Department of Physics and Scryent. For
beginners, PyCamp makes you productive so you can get your work done
quickly. PyCamp emphasizes the features which make Python a simpler and
more efficient language. Following along by example speeds your learning
process in a modern high-tech classroom. Become a self-sufficient Python
developer in just five days at PyCamp!

http://pycamp.org

-- 
Sincerely,

Chris Calloway
http://www.secoora.org
office: 332 Chapman Hall   phone: (919) 599-3530
mail: Campus Box #3300, UNC-CH, Chapel Hill, NC 27599





From cbc at unc.edu  Thu Jul  2 13:52:48 2009
From: cbc at unc.edu (Chris Calloway)
Date: Thu, 02 Jul 2009 13:52:48 -0400
Subject: Deadline for Toronto PyCamp Registraiton Appoaching
Message-ID: <4A4CF3F0.4020304@unc.edu>

Tomorrow (July 3) by midnight will be the last opportunity for Toronto 
PyCamp registration before the late registration period ending July 10.

PyCamp is the original Python BootCamp developed by a user group for
user groups. This year PyCamp is July 13-17 at the University of
Toronto, sponsored by the Department of Physics and Scryent. For
beginners, PyCamp makes you productive so you can get your work done
quickly. PyCamp emphasizes the features which make Python a simpler and
more efficient language. Following along by example speeds your learning
process in a modern high-tech classroom. Become a self-sufficient Python
developer in just five days at PyCamp!

http://pycamp.org

-- 
Sincerely,

Chris Calloway
http://www.secoora.org
office: 332 Chapman Hall   phone: (919) 599-3530
mail: Campus Box #3300, UNC-CH, Chapel Hill, NC 27599



-- 
http://mail.python.org/mailman/listinfo/python-announce-list

        Support the Python Software Foundation:
        http://www.python.org/psf/donations/
.


From hobesh at gmail.com  Thu Jul  2 13:56:10 2009
From: hobesh at gmail.com (Zach Hobesh)
Date: Thu, 2 Jul 2009 10:56:10 -0700
Subject: Config files with different types
Message-ID: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>

Hi all,

I've written a function that reads a specifically formatted text file
and spits out a dictionary. ?Here's an example:

config.txt:

Destination = C:/Destination
Overwrite = True


Here's my function that takes 1 argument (text file)

the_file = open(textfile,'r')
linelist = the_file.read().split('\n')
the_file.close()
configs = {}
for line in linelist:
       try:
              key,value = line.split('=')
              key.strip()
              value.strip()
              key.lower()
              value.lower()
              configs[key] = value

       except ValueError:
              break

so I call this on my config file, and then I can refer back to any
config in my script like this:

shutil.move(your_file,configs['destination'])

which I like because it's very clear and readable.

So this works great for simple text config files.  Here's how I want
to improve it:

I want to be able to look at the value and determine what type it
SHOULD be.  Right now, configs['overwrite'] = 'true' (a string) when
it might be more useful as a boolean.  Is there a quick way to do
this?  I'd also like to able to read '1' as an in, '1.0' as a float,
etc...

I remember once I saw a script that took a string and tried int(),
float() wrapped in a try except, but I was wondering if there was a
more direct way.

Thanks in advance,

Zach


From db3l.net at gmail.com  Thu Jul  2 13:58:24 2009
From: db3l.net at gmail.com (David Bolen)
Date: Thu, 02 Jul 2009 13:58:24 -0400
Subject: Suppressing Implicit Chained Exceptions (Python 3.0)
References: <mailman.2447.1246492174.8015.python-list@python.org>
Message-ID: <m23a9fezlr.fsf@valheru.db3l.homeip.net>

"andrew cooke" <andrew at acooke.org> writes:

> However, when printed via format_exc(), this new exception still has the
> old exception attached via the mechanism described at
> http://www.python.org/dev/peps/pep-3134/ (this is Python 3.0).

If you're in control of the format_exc() call, I think the new chain
keyword parameter can disable this and restore the old behavior.

If you're not in control of the traceback display, I'm not sure there's
an easy way to prevent it, given that displaying chained exceptions is
the default mode.

-- David


From sajmikins at gmail.com  Thu Jul  2 13:58:56 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 10:58:56 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
Message-ID: <e3e2df13-d0f5-4e79-a55c-cfd52b2997f8@h2g2000yqg.googlegroups.com>

On Jul 2, 1:44?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> wrote:
> > Hey I was hoping to get your opinions on a sort of minor stylistic
> > point.
> > These two snippets of code are functionally identical. Which would you
> > use and why?
> > The first one is easier [for me anyway] to read and understand, but
> > slightly less efficient, while the second is [marginally] harder to
> > follow but more efficient.
>
> > ## First snippet
>
> > if self.higher is self.lower is None: return
> > if self.lower is None: return self.higher
> > if self.higher is None: return self.lower
>
> > ## Second snippet
>
> > if self.higher is None:
> > ? ? if self.lower is None:
> > ? ? ? ? return
> > ? ? return self.lower
> > if self.lower is None:
> > ? ? return self.higher
>
> > What do you think?
>
> > (One minor point: in the first snippet, the "is None" in the first
> > line is superfluous in the context in which it will be used, the only
> > time "self.lower is self.higher" will be true is when they are both
> > None.)
>
> I'd write the first one as:
>
> ? ? ? ? if self.lower is None:
> ? ? ? ? ? ? ? ? return self.higher
> ? ? ? ? if self.higher is None:
> ? ? ? ? ? ? return self.lower
>
> because the entire first 'if' statement is redundant.
>
> As a matter of style however I wouldn't use the shorthand to run two 'is'
> comparisons together, I'd write that out in full if it was actually needed
> here.
>
> Likewise in the second one:
>
> ? ? if self.lower is None:
> ? ? ? ? return
> ? ? return self.lower
>
> is obviously the same as:
>
> ? ? ? ? return self.lower
>
> so apart from reversing the order of the comparisons once you've dropped
> the redundant test it is the same as the first one.

Wow. The equivalence in the second bit is obvious enough-- in
hindsight :] but I totally missed the redundancy in the first bit. I
must be getting old.

Thank you very much.


From charles at declareSub.com  Thu Jul  2 14:00:51 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Thu, 2 Jul 2009 14:00:51 -0400
Subject: PEP 376
In-Reply-To: <1f63m.2229$ze1.1410@news-server.bigpond.net.au>
References: <mailman.2410.1246390911.8015.python-list@python.org>		<h2ec5l$820$1@lust.ihug.co.nz>		<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>		<mailman.2422.1246418400.8015.python-list@python.org>		<h2f7jt$j33$1@south.jnrs.ja.net>	<4A4C685A.8020300@Strombergson.com>	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
	<1f63m.2229$ze1.1410@news-server.bigpond.net.au>
Message-ID: <EF743CC8-5AFE-47F5-97A9-AF993BD4B6C7@declareSub.com>


On Jul 2, 2009, at 1:37 PM, Lie Ryan wrote:

> Joachim Str?mbergson wrote:
>> Aloha!
>>
>> Tarek Ziad? wrote:
>>> The prefix is a good idea but since it's just a checksum to control
>>> that the file hasn't changed
>>> what's wrong with using a weak hash algorithm like md5 or now sha1 ?
>>
>> Because it creates a dependency to an old algorithm that should be
>> deprecated. Also using MD5, even for a thing like this might make  
>> people
>> belive that it is an ok algorithm to use - "Hey, it is used by the
>> default install in Python, so it must be ok, right?"
>>
>> If we flip the argument around: Why would you want to use MD5  
>> instead of
>> SHA-256? For the specific use case the performance will not (should  
>> not)
>> be an issue.
>>
>> As I wrote a few mails ago, it is time to move forward from MD5 and
>> designing something in 2009 that will be around for many years that  
>> uses
>> MD5 is (IMHO) a bad design decision.
>>
>>> If someone wants to modify a file of a distribution he can recreate
>>> the checksum as well,
>>> the only secured way to prevent that would be to use gpg keys but
>>> isn't that overkill for what we need ?
>>
>> Actually, adding this type of security would IMHO be a good idea.
>>
>
> Now, are we actually talking about security or checksum?
>
> It has been known for years that MD5 is weak, weak, weak. Not just in
> the recent years. But it doesn't matter since MD5 was never designed  
> for
> security, MD5 was designed to protect against random bits  
> corruption. If
> you want security, look at least to GPG. For data protection against
> intentional, malicious forging, definitely MD5 is the wrong choice.  
> But
> when you just want a simple checksum to ensure that a faulty router
> somewhere in the internet backbone doesn't destroying your data, MD5  
> is
> a fine algorithm.
> -- 

On the contrary, MD5 was intended to be a cryptographic hash function,  
not a checksum.

Charles Yeomans





From python at mrabarnett.plus.com  Thu Jul  2 14:12:07 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 02 Jul 2009 19:12:07 +0100
Subject: Config files with different types
In-Reply-To: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
References: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
Message-ID: <4A4CF877.6030906@mrabarnett.plus.com>

Zach Hobesh wrote:
> Hi all,
> 
> I've written a function that reads a specifically formatted text file
> and spits out a dictionary.  Here's an example:
> 
> config.txt:
> 
> Destination = C:/Destination
> Overwrite = True
> 
> 
> Here's my function that takes 1 argument (text file)
> 
> the_file = open(textfile,'r')
> linelist = the_file.read().split('\n')

You could use .splitlines() or iterate over the file itself.

> the_file.close()
> configs = {}
> for line in linelist:
>        try:
>               key,value = line.split('=')
>               key.strip()
>               value.strip()
>               key.lower()
>               value.lower()

Strings are immutable. These methods don't modify the strings, but
_return_ the result.

>               configs[key] = value
> 
>        except ValueError:
>               break
> 
'break' will leave the loop. Is this intentional?

> so I call this on my config file, and then I can refer back to any
> config in my script like this:
> 
> shutil.move(your_file,configs['destination'])
> 
> which I like because it's very clear and readable.
> 
> So this works great for simple text config files.  Here's how I want
> to improve it:
> 
> I want to be able to look at the value and determine what type it
> SHOULD be.  Right now, configs['overwrite'] = 'true' (a string) when
> it might be more useful as a boolean.  Is there a quick way to do
> this?  I'd also like to able to read '1' as an in, '1.0' as a float,
> etc...
> 
> I remember once I saw a script that took a string and tried int(),
> float() wrapped in a try except, but I was wondering if there was a
> more direct way.
> 
The way you saw was the safe, and recommended, way.

When checking for Boolean you might want to ignore the case; something
like:

bool_dict = {"false": False, "true": True}
...
try:
     value = bool_dict[value.strip().lower()]
except ValueError:
     # Not a Boolean.
     ...


From kee at kagi.com  Thu Jul  2 14:12:29 2009
From: kee at kagi.com (Kee Nethery)
Date: Thu, 2 Jul 2009 11:12:29 -0700
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <A229B59E-2428-449C-A182-C93E7EB732BB@kagi.com>

the fact that you felt compelled to explain the "one minor point" in  
the first snippet tells me that the second snippet does not need that  
explanation and will be easier for someone (like you for example) to  
maintain in the future.
Second snippet would be my choice.
Kee Nethery

On Jul 2, 2009, at 10:23 AM, Simon Forman wrote:

> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
>
> ## First snippet
>
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
>
> ## Second snippet
>
> if self.higher is None:
>    if self.lower is None:
>        return
>    return self.lower
> if self.lower is None:
>    return self.higher
>
> What do you think?
>
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)
> -- 
> http://mail.python.org/mailman/listinfo/python-list




-------------------------------------------------
I check email roughly 2 to 3 times per business day.
Kagi main office: +1 (510) 550-1336




From pavlovevidence at gmail.com  Thu Jul  2 14:36:38 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 2 Jul 2009 11:36:38 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
Message-ID: <6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>

On Jul 2, 3:12?am, Ulrich Eckhardt <eckha... at satorlaser.com> wrote:
> Bearophile wrote:
> > Ulrich Eckhardt:
> >> a way to automatically release the resource, something
> >> which I would do in the destructor in C++.
>
> > Is this helpful?
> >http://effbot.org/pyref/with.htm
>
> Yes, it aims in the same direction. However, I'm not sure this applies to my
> case. The point is that the resource handle is not just used locally in a
> restricted scope but it is allocated and stored. The 'with' is something
> that makes sense in the context of mutex locking, where you have a
> well-defined critical section. What I need is something similar to open(),
> which returs a file. When the last reference to that object goes out of
> scope, the underlying file object is closed.

On CPython you can do it with a __del__ attribute.

Warning: objects with a __del__ attribute prevent reference cycle
detection, which can potentially lead to memory (and resource) leaks.
So you must be careful to avoid creating reference loops with that
object.

Note that file objects have a close method; you can explicitly close
it at any time.  Your object should follow that example, and define a
close (or release, or whatever) method.  I'd recommend making an
effort to call it and to rely on __del__ as little as possible.


Carl Banks


From nobody at nowhere.com  Thu Jul  2 14:41:54 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 02 Jul 2009 19:41:54 +0100
Subject: regex question on .findall and \b
References: <mailman.2500.1246554153.8015.python-list@python.org>
Message-ID: <pan.2009.07.02.18.41.54.281000@nowhere.com>

On Thu, 02 Jul 2009 09:38:56 -0700, Ethan Furman wrote:

> Greetings!
> 
> My closest to successfull attempt:
> 
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel)]
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.9.1 -- An enhanced Interactive Python.
> 
>    In [161]: re.findall('\d+','this is test a3 attempt 79')
>    Out[161]: ['3', '79']
> 
> What I really want in just the 79, as a3 is not a decimal number, but 
> when I add the \b word boundaries I get:
> 
>    In [162]: re.findall('\b\d+\b','this is test a3 attempt 79')
>    Out[162]: []
> 
> What am I missing?

You need to use a raw string (r'...') to prevent \b from being interpreted
as a backspace:

	re.findall(r'\b\d+\b','this is test a3 attempt 79')

\d isn't a recognised escape sequence, so it doesn't get interpreted:

	> print '\b'
	^H
	> print '\d'
	\d
	> print r'\b'
	\b

Try to get into the habit of using raw strings for regexps.



From tjreedy at udel.edu  Thu Jul  2 14:53:43 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 02 Jul 2009 14:53:43 -0400
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <h2ivno$cl8$1@ger.gmane.org>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
> 
> ## First snippet
> 
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
> 
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher

What happen is neither is None?



From james at agentultra.com  Thu Jul  2 14:54:49 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 02 Jul 2009 14:54:49 -0400
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
	<851vozf4rh.fsf@agentultra.com>
	<cd3362ac-e189-4dea-93d5-06db3aaafd29@c36g2000yqn.googlegroups.com>
Message-ID: <85ws6qewzq.fsf@agentultra.com>

masher <vertespain at gmail.com> writes:

> On Jul 2, 12:06?pm, J Kenneth King <ja... at agentultra.com> wrote:
>> masher <vertesp... at gmail.com> writes:
>> > My questions, then, is: Is there a more elegant/pythonic way of doing
>> > what I am trying to do with the current Pool class?
>>
>> Forgive me, I may not fully understand what you are trying to do here
>> (I've never really used multiprocessing all that much)...
>>
>> But couldn't you just assign your own Queue object to the Pool instance?
>
> That's basically my question. It does not appear as though there is
> any straightforward way of doing this because of the design of Pool's
> __init__ method, which passes _taskqueue to several functions. Hence,
> even if I were to reassign _taskqueue after __init__, that wouldn't
> change anything.

I think I understand.

There are ways to modify the class before instantiating it, but even the
most clever or elegant solution will still smell funny.  I suppose this
might be worth submitting as a feature suggestion to the multiprocessing
project.

Best of luck.


From rdrehoff at technotraining.net  Thu Jul  2 14:57:40 2009
From: rdrehoff at technotraining.net (Rich Drehoff)
Date: Thu, 2 Jul 2009 14:57:40 -0400
Subject: Intro to Python class, 7/21-23, Ft Worth TX
Message-ID: <000901c9fb46$faa21ae0$efe650a0$@net>

We are looking for someone that can help with the subject class, Intro to
Python class, 7/21-23, Ft Worth TX.  Please let me know if you can help.
Would need your resume and best possible daily rate.

 

Best regards,

 

Rich Drehoff

TechnoTraining, Inc.

328 Office Square Lane, Ste. 202, Virginia Beach, VA 23462-3648

(757) 425-0728 x15 / (757) 425-7323 Fax

Email: RDrehoff at TechnoTraining.net

Website: www.TechnoTraining.net <http://www.technotraining.net/> 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/643498d7/attachment-0001.html>

From andrew at acooke.org  Thu Jul  2 15:07:20 2009
From: andrew at acooke.org (andrew cooke)
Date: Thu, 2 Jul 2009 15:07:20 -0400 (CLT)
Subject: Suppressing Implicit Chained Exceptions (Python 3.0)
Message-ID: <7915bc3d5213848b805f461940e3cbec.squirrel@localhost>

David Bolen wrote:
> "andrew cooke" <andrew at acooke.org> writes:
>
>> However, when printed via format_exc(), this new exception still has
the old exception attached via the mechanism described at
>> http://www.python.org/dev/peps/pep-3134/ (this is Python 3.0).
>
> If you're in control of the format_exc() call, I think the new chain
keyword parameter can disable this and restore the old behavior.
>
> If you're not in control of the traceback display, I'm not sure there's
an easy way to prevent it, given that displaying chained exceptions is
the default mode.

Yeah, that's the impression I got too.

Just in case it wasn't clear, I'd like the chaining not to exist at all in
this case), so that it doesn't appear in format_exc outside my control.

Thanks,
Andrew






From thudfoo at opensuse.us  Thu Jul  2 15:10:41 2009
From: thudfoo at opensuse.us (member thudfoo)
Date: Thu, 2 Jul 2009 12:10:41 -0700
Subject: Open Source RSS Reader in Python?
In-Reply-To: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
References: <50675e1c-91e4-4774-83bd-9e9e8fc1679a@z34g2000vbl.googlegroups.com>
Message-ID: <3d881a310907021210haabc998x9e4f678299716462@mail.gmail.com>

On Wed, Jul 1, 2009 at 4:18 PM, Alex<alex.lavoro.propio at gmail.com> wrote:
> I am looking for an open source RSS reader (desktop, not online)
> written in Python but in vain. I am not looking for a package but a
> fully functional software.
>
> Google: python "open source" (rss OR feeds) reader
>
> Any clue ?
> --
> http://mail.python.org/mailman/listinfo/python-list
>

rawdog is an RSS Aggregator Without Delusions Of Grandeur. It is a
"river of news"-style aggregator: it uses feedparser to download feeds
in RSS, Atom and a variety of other formats, and (by default) produces
static HTML pages containing the newest articles in date order. For
example, rawdog's default configuration produces output that looks
like this:

http://offog.org/code/rawdog.html


From http  Thu Jul  2 15:13:48 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 12:13:48 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <7x63eahp8z.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> These two snippets of code are functionally identical. Which would you
> use and why?

Both are terrible.  I can't tell what you're really trying to do.  As
Terry Reedy points out, the case where self.higher and self.lower are
both not None is not handled.  If you want to explicitly return None,
use "return None" rather than "return".  Generally, having a special
value like None to denote a missing datum was considered standard
practice a few decades ago, but these days in some circles it's
treated as something of a code smell.  You may want to look for
some other representation instead.

Most importantly, whatever code you write, put in an explanatory
comment saying what the real goal is.


From usernet at ilthio.net  Thu Jul  2 15:16:25 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 19:16:25 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
Message-ID: <dI73m.3603$Jb1.569@flpi144.ffdc.sbc.com>

On 2009-07-02, Duncan Booth <duncan.booth at invalid.invalid> wrote:
> so apart from reversing the order of the comparisons once you've dropped 
> the redundant test it is the same as the first one.

I try to evaluate what you have given regardless of what Booth pointed out.
So, I will only evaluate the first line as it contains most of what I want
to illistrate.

> Simon Forman <sajmikins at gmail.com> wrote:
>> if self.higher is self.lower is None: return

I *really* don't like the fact that you don't specify a return value here
when you have specified a return value for the other conditions.  Obviously
it is possible that something will be looking at the return value for this
function (ie, it would not be a void function() in C).  I had to lookup to
make sure what Python would return in such a case.  If you want the
condition to return something then you should specify what you are
returning.  Specifing 'return None' is much clearer then relying on default
behavior.

I always prefer to see a:
	
	condition:
		operation

structure to my code.  It is the way it is almost always see in Python and
in other languages.  Putting it on one line doesn't save you anything and
it makes it easier to miss something.

I have no particular problem with running the is statements together as an
extended if statement together when it makes it clearer to do so.  The fact
that you want all of them to be the same object is clear.  I do have some
wroblem in this instance because you are referencing "is" against an
instance of a builtin object.

The fact that you used is instead of == for this particular instance
throws me a little because of the use of None.  I wouldn't think second
about it if it was a user defined object.  I have to wonder whether all
objects that are assigned the value of None are actually re-referenced
to the origional None object?  Could deep copy style operations create
two equivilant but different copys of none?  The same problems may be
encounted from any builtin objects such as number literals.

Had None not been specified I would be fine with stringing the comparison
together:

# if all three objects are the same instance, return None
if object1 is object2 is object3:
	return None:

Because of this pecularity, I think that it would be clearer to break the
ifs for simularity and equality:

if object1 is object2:
	if object1 == None:
		return None
	else:
		return object1
else:
	if object1 == None:
		return Object2
	elif object2 == None::
		return Object1
	else:
		# what do we do if neither object == None?
		raise houstonWeHaveAProblemException


From Scott.Daniels at Acm.Org  Thu Jul  2 15:57:57 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Thu, 02 Jul 2009 12:57:57 -0700
Subject: question of style
In-Reply-To: <Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
Message-ID: <gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>

Duncan Booth wrote:
> Simon Forman <sajmikins at gmail.com> wrote:
>> ...
>> if self.higher is self.lower is None: return
>> ...

> As a matter of style however I wouldn't use the shorthand to run two 'is' 
> comparisons together, I'd write that out in full if it was actually needed 
> here.

Speaking only to the style issue, when I've wanted to do something like
that, I find:

       if self.higher is None is self.lower:
           ...

more readable, by making clear they are both being compared to a
constant, rather than compared to each other.

More often, I've used code like:

       if <expr1> is not None is not <expr2>:
           ...

since I am usually working on non-defaulting cases in the body.
I find the form above simpler to read than:

       if <expr1> is not None and <expr2> is not None:
           ...

I do draw the line at two, though, and with three or more I'll
paren-up a list of parallel comparisons:

       if (<expr1> is not None
         and <expr2> is not None
         and <expr3> is not None):
           ...

--Scott David Daniels
Scott.Daniels at Acm.Org


From http  Thu Jul  2 16:02:58 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 13:02:58 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <7xws6qrgy5.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
> 
> What do you think?

I'm not sure, but my guess is that what you are really trying to write
is something like this:

   # self.higher and self.lower are each either "available" (i.e.  are
   # not None), or unavailable (are None).  Return the highest of the
   # available values.  If no value is available, return None.

   if self.higher is not None: 
       return self.higher
   elif self.lower is not None: 
       return self.lower
   else: 
       return None


From sanket.s.patel at gmail.com  Thu Jul  2 16:07:54 2009
From: sanket.s.patel at gmail.com (sanket)
Date: Thu, 2 Jul 2009 13:07:54 -0700 (PDT)
Subject: how to spawn a process under different user
Message-ID: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>

Hello All,

I am trying to use python's subprocess module to launch a process.
but in order to do that I have to change the user.

I am not getting any clue how to do that?
so can anyone please tell me How can I spawn a process under different
user than currently I am logging in as.

Thank you,
sanket


From max at alcyone.com  Thu Jul  2 16:08:57 2009
From: max at alcyone.com (Erik Max Francis)
Date: Thu, 02 Jul 2009 13:08:57 -0700
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
> 
> ## First snippet
> 
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
> 
> ## Second snippet
> 
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
> 
> What do you think?

Explicit is always better, `return None` when that is your intent. 
`return` shouts to the reader, "I want to get out of this function now, 
and no one cares about the return result."

Personally, I only use the one-liner if/else clauses if it's an 
extremely trivial condition, and even then, usually not there.  (The 
only place I use it consistently is `if __name__ == '__main__': 
main()`.)  If it's part of something more important that needs 
inspection -- as this obviously does given the questions you've had 
about it, doesn't skip space.  Newlines are free.

Even when expanding about the first test, there's no reason to do 
chained `if`s.  One `if` with an `and` works just fine.

Paul Rubin's looked to be the best overall replacement, as the logic 
here looks strangely turned inside out.  You're obviously looking for 
which one _isn't_ `None`, so write the tests that way.  It's much easier 
for everyone else (including your potential future self) to follow.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   They are ill discoverers that think there is no land when they can
    see nothing but sea. -- Francis Bacon


From usernet at ilthio.net  Thu Jul  2 16:27:33 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 20:27:33 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
Message-ID: <VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>

On 2009-07-02, Scott David Daniels <Scott.Daniels at Acm.Org> wrote:
> Duncan Booth wrote:
>> Simon Forman <sajmikins at gmail.com> wrote:
>> As a matter of style however I wouldn't use the shorthand to run two 'is' 
>> comparisons together, I'd write that out in full if it was actually needed 
>> here.

That part I don't really have a problem with.  The chained is statements
can actually be much clearer burying the tests into nested ifs.  Nested ifs
get the same result but they also give an immediate impression that the
control structure might be looking for more then a single test result.  I
have to walk through the ifs to see all of the potential results one is
looking for before I know what the entire control struture is doing.
Multiple is operators makes it clear that I just want everything to be the
same.  The same would not be true if the operators where not all equilance
operators ( is and == are clear as long as they are not mixed; but <, >=,
!= would be more confusing).

> Speaking only to the style issue, when I've wanted to do something like
> that, I find:
>        if self.higher is None is self.lower:
> more readable, by making clear they are both being compared to a
> constant, rather than compared to each other.

By comparing them to *any* constant with 'is' you end up with the same
potential problems as to whether something with a value of None is actually
None?  Is something with the value of 3 actually the same object as 3?
What about if I make a deep copy?  Can I have several objects with the
value of three, all the same 3 object, or maybe even a combination of 1
separate 3 object with two other objects of the same 3.

Is
	if self.higher == None == self.lower:
any more clear then:
	if self.higher == self.lower == None:
I don't personally have a problem with either.

> More often, I've used code like:
>        if <expr1> is not None is not <expr2>:
> since I am usually working on non-defaulting cases in the body.
> I find the form above simpler to read than:
>        if <expr1> is not None and <expr2> is not None:

This is a much more compicated expression.  With equality operators
everything is either the same or it isn't.   I can start from the first
variable and compare it to the second then to the third then ...  In the
case of the inequality, I have to start with the first and compare it to
all of the rest to make sure that none are the same.  Then I have to do the
same for each with the remaining.  This is much more difficult to do in my
head.  I requires much more thought, better left to a computer, when
evaluating the expression for myself.  Therefore, equalites are quick and
easy to keep straight whereas any inequalites are more error prone when
trying to evaluate how a section of code will react under different
circumstances.

> I do draw the line at two, though, and with three or more I'll
> paren-up a list of parallel comparisons:

As long as everything is an equality, then I don't mind comparing to the
end of an 70 column line.  Mixed types of equalities or inequalities
require too many operations mentally evaluate safely.


From bpytlik at sun.com  Thu Jul  2 16:31:35 2009
From: bpytlik at sun.com (Brock Pytlik)
Date: Thu, 02 Jul 2009 13:31:35 -0700
Subject: System default sys.path
In-Reply-To: <81a8195ca5ecf44f3bf9ddbfaae37bdc@preisshare.net>
References: <4A4C1FE4.1070901@sun.com>
	<81a8195ca5ecf44f3bf9ddbfaae37bdc@preisshare.net>
Message-ID: <4A4D1927.5070305@sun.com>

David Lyon wrote:
> On Wed, 01 Jul 2009 19:48:04 -0700, Brock Pytlik <bpytlik at Sun.COM> wrote:
>   
>> Hi, I'm trying to find a way to get the value sys.path would have on a 
>> particular system if python was started with an empty python path. I do 
>> want it to include the site specific additional paths. I know I can hack 
>> this information myself, 
>>     
>
> Copy the code out from site.py...
>
>   
Well, as far as I can tell, site does several things. It calls 
abs__file__ which, afaict, doesn't effect sys.path. Then it calls 
removeduppaths, which walks over sys.path. That means that sys.path has 
already been set by something at that point. So, how/where did sys.path 
get set then? Or is sys.path always empty there at startup and this code 
is just to handle other situations?

[snip]

Brock


From usernet at ilthio.net  Thu Jul  2 16:37:13 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 20:37:13 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
Message-ID: <ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>

On 2009-07-02, Paul Rubin <http> wrote:
[reformated with emphasis added]
>    #self.higher and self.lower are each either "available" (i.e.  are not
>    #None), or unavailable (are None).  [EMPHASIS] Return the highest of the
>    #available values. [/EMPHASIS]  If no value is available, return None.

Your code doesn't do what your comment says (notice EMPHASIS tags):

>    if self.higher is not None: 
>        return self.higher
>    elif self.lower is not None: 
>        return self.lower
>    else: 
>        return None

If lower is 5 and higher is 3, then it returns 3 because 3 != None in the
first if.


From dfstrauss at gmail.com  Thu Jul  2 16:49:00 2009
From: dfstrauss at gmail.com (Dawie Strauss)
Date: Thu, 2 Jul 2009 13:49:00 -0700 (PDT)
Subject: PyTextMagicSMS text messaging library released
Message-ID: <2b583f41-78d7-4a7e-a925-04934efe5458@m7g2000prd.googlegroups.com>

TextMagic (http://www.textmagic.com) offers a convenient way to send
text messages programmatically. This package provides a simple Python
API on top of the TextMagic HTTPS API.

Project documentation and source code is hosted at
http://code.google.com/p/textmagic-sms-api-python/

The package can be dowloaded from http://pypi.python.org/pypi/PyTextMagicSMS/



From user at example.net  Thu Jul  2 16:57:49 2009
From: user at example.net (superpollo)
Date: Thu, 02 Jul 2009 22:57:49 +0200
Subject: stringio+tarfile
Message-ID: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>

why the following does not work? can you help me correct (if possible)?

       1 import tarfile
       2 import StringIO
       3 sf1 = StringIO.StringIO("one\n")
       4 sf2 = StringIO.StringIO("two\n")
       5 tf = StringIO.StringIO()
       6 tar = tarfile.open(tf , "w")
       7 for name in [sf1 , sf2]:
       8     tar.add(name)
       9 print tf
      10 sf1.close()
      11 sf2.close()
      12 tf.close()
      13 tar.close()

tia


From mail at timgolden.me.uk  Thu Jul  2 16:58:03 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 02 Jul 2009 21:58:03 +0100
Subject: how to spawn a process under different user
In-Reply-To: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
Message-ID: <4A4D1F5B.6070605@timgolden.me.uk>

sanket wrote:
> Hello All,
> 
> I am trying to use python's subprocess module to launch a process.
> but in order to do that I have to change the user.
> 
> I am not getting any clue how to do that?
> so can anyone please tell me How can I spawn a process under different
> user than currently I am logging in as.

What platform are you on? If you are on Windows,
there was a thread on this subject some time in
the last month. (Short answer: switching user before
launching subprocess won't work; switching within
the subprocess will...)

TJG


From rschroev_nospam_ml at fastmail.fm  Thu Jul  2 17:28:19 2009
From: rschroev_nospam_ml at fastmail.fm (Roel Schroeven)
Date: Thu, 02 Jul 2009 23:28:19 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <h2i35q$mp4$01$1@news.t-online.com>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<h2i35q$mp4$01$1@news.t-online.com>
Message-ID: <UD93m.9416$IA6.7106@newsfe01.ams2>

Peter Otten schreef:
> Ulrich Eckhardt wrote:
> 
>> Bearophile wrote:
>>> Ulrich Eckhardt:
>>>> a way to automatically release the resource, something
>>>> which I would do in the destructor in C++.
>>> Is this helpful?
>>> http://effbot.org/pyref/with.htm
>> Yes, it aims in the same direction. However, I'm not sure this applies to
>> my case. The point is that the resource handle is not just used locally in
>> a restricted scope but it is allocated and stored. The 'with' is something
>> that makes sense in the context of mutex locking, where you have a
>> well-defined critical section. 
> 
> Isn't that exactly what RAII does?

RAII also works if the resource handle is stored, for example, in a data
member of an object. If that object is destroyed (because it goes out of
scope, or because it is deleted), the resource is automatically
destroyed too.

The way RAII works is actually the one thing from C++ that I miss in Python.

-- 
The saddest aspect of life right now is that science gathers knowledge
faster than society gathers wisdom.
  -- Isaac Asimov

Roel Schroeven


From http  Thu Jul  2 17:43:38 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 14:43:38 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
Message-ID: <7xocs2222d.fsf@ruckus.brouhaha.com>

Tim Harig <usernet at ilthio.net> writes:
> If lower is 5 and higher is 3, then it returns 3 because 3 != None in the
> first if.

Sorry, the presumption was that lower <= higher, i.e. the comparison
had already been made and the invariant was enforced by the class
constructor.  The comment should have been more explicit, I guess.


From sanket.s.patel at gmail.com  Thu Jul  2 17:56:30 2009
From: sanket.s.patel at gmail.com (sanket)
Date: Thu, 2 Jul 2009 14:56:30 -0700 (PDT)
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
Message-ID: <25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>

On Jul 2, 1:58?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> sanket wrote:
> > Hello All,
>
> > I am trying to use python's subprocess module to launch a process.
> > but in order to do that I have to change the user.
>
> > I am not getting any clue how to do that?
> > so can anyone please tell me How can I spawn a process under different
> > user than currently I am logging in as.
>
> What platform are you on? If you are on Windows,
> there was a thread on this subject some time in
> the last month. (Short answer: switching user before
> launching subprocess won't work; switching within
> the subprocess will...)
>
> TJG

Hi TJG,
Thanks for the reply.

I am using python 2.4 on centos.

Thanks,
sanket


From hannarosie at gmail.com  Thu Jul  2 18:05:46 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Thu, 2 Jul 2009 15:05:46 -0700
Subject: String to List Question
Message-ID: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>

Hi,

I am brand new to python and I love it, but I've been having some trouble
with a file parser that I've been working on. It contains lines that start
with a name and then continue with names, nicknames and phone numbers of
people associated with that name. I need to create a list of the names of
people associated with each singular person (the first name in each line).
Each name/phone number is separated by a tab but if someone doesn't have a
nickname there are two tabs between their name and number.

I've been trying to figure out how to test for two tabs, skip over these
people and move onto the next name but I just can't figure out how that will
work in python.

Any help would be greatly appreciated!

Thanks,
Hanna
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/84d46e24/attachment-0001.html>

From allen.fowler at yahoo.com  Thu Jul  2 18:06:17 2009
From: allen.fowler at yahoo.com (Allen Fowler)
Date: Thu, 2 Jul 2009 15:06:17 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP:  How to define API?
Message-ID: <115250.26948.qm@web45607.mail.sp1.yahoo.com>


I have an (in-development) python system that needs to shuttle events / requests around over the network to other parts of itself.   It will also need to cooperate with a .net application running on yet a different machine.

So, naturally I figured some sort of HTTP event / RPC type of would be a good idea?

Are there any modules I should know about, or guidelines I could read, that could aid me in the design of the API?    


Thank you,
:)


      



From usernet at ilthio.net  Thu Jul  2 18:14:18 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:14:18 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
Message-ID: <_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>

On 2009-07-02, Paul Rubin <http> wrote:
> Tim Harig <usernet at ilthio.net> writes:
>> If lower is 5 and higher is 3, then it returns 3 because 3 != None in the
>> first if.
> Sorry, the presumption was that lower <= higher, i.e. the comparison
> had already been made and the invariant was enforced by the class
> constructor.  The comment should have been more explicit, I guess.

That being the case, it might be a good idea either to handle the situation
and raise an exception or add:

assert self.lower <= self.higher

That way an exception will be raised if there is an error somewhere else
in the code rather then silently passing a possibly incorrect value.


From philip at semanchuk.com  Thu Jul  2 18:15:03 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 2 Jul 2009 18:15:03 -0400
Subject: String to List Question
In-Reply-To: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
References: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
Message-ID: <76DF2C44-9A40-4FC9-AA20-CEDC3ED37806@semanchuk.com>


On Jul 2, 2009, at 6:05 PM, Hanna Michelsen wrote:

> Hi,
>
> I am brand new to python and I love it, but I've been having some  
> trouble
> with a file parser that I've been working on. It contains lines that  
> start
> with a name and then continue with names, nicknames and phone  
> numbers of
> people associated with that name. I need to create a list of the  
> names of
> people associated with each singular person (the first name in each  
> line).
> Each name/phone number is separated by a tab but if someone doesn't  
> have a
> nickname there are two tabs between their name and number.
>
> I've been trying to figure out how to test for two tabs, skip over  
> these
> people and move onto the next name but I just can't figure out how  
> that will
> work in python.
>
> Any help would be greatly appreciated!

Hi Hanna,
Are you familiar with a string's split() function? It sounds like just  
what you need.

http://docs.python.org/library/stdtypes.html#str.split

HTH
Philip



From allen.fowler at yahoo.com  Thu Jul  2 18:17:56 2009
From: allen.fowler at yahoo.com (Allen Fowler)
Date: Thu, 2 Jul 2009 15:17:56 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP:  How to define API?
Message-ID: <219972.64445.qm@web45607.mail.sp1.yahoo.com>





> I have an (in-development) python system that needs to shuttle events / requests 
> around over the network to other parts of itself.   It will also need to 
> cooperate with a .net application running on yet a different machine.
> 
> So, naturally I figured some sort of HTTP event / RPC type of would be a good 
> idea?
> 
> Are there any modules I should know about, or guidelines I could read, that 
> could aid me in the design of the API?    
> 
> 


To clarify:

Each message would be <1KB of data total, and consist of some structured object containing strings, numbers, dates, etc.

For instance there would be an "add user" request that would contain one or more User objects each having a number of properties like:

- Full Name
- Username
- Password
- Email addresses (a variable length array)
- Street Address line1
- Street Address line1
- Street Address line1
- City
- State
- Zip
- Sign Up Date

.... and so on.


Since I need to work with other platforms, pickle is out...  what are the alternatives?  XML? JSON?

How should I formally define each of the valid messages and objects?

Thank you,
:)



      



From mccdo at iastate.edu  Thu Jul  2 18:22:07 2009
From: mccdo at iastate.edu (Doug McCorkle)
Date: Thu, 2 Jul 2009 17:22:07 -0500
Subject: Detecting platform architecture with Parallels and Win XP x64
Message-ID: <8B80C75F-1F27-4E65-8BAE-C77441235943@iastate.edu>

Hello,

I am using Python 2.5.4 on Windows XP x64 with Parallels. When I try  
to use:

distutils.util.get_platform
sys.platform

I always get win32 but if I use:

platform.architecture()

with the amd64 installer I get 64bit for the first argument. Is there  
a way to detect win64 without having to use the python executable to  
see if the application is on a 64bit architecture? Thanks.

Doug




From usernet at ilthio.net  Thu Jul  2 18:27:05 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:27:05 GMT
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
	<25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>
Message-ID: <Zua3m.3615$Jb1.1092@flpi144.ffdc.sbc.com>

On 2009-07-02, sanket <sanket.s.patel at gmail.com> wrote:
>> sanket wrote:
>> > I am trying to use python's subprocess module to launch a process.
>> > but in order to do that I have to change the user.
> I am using python 2.4 on centos.

I have never done this in python; but, using the normal system calls in C
the process is basically:
	
	1. fork() a  new process
	2. the child process changes its user id with setreuid() and
		possibly its group id with setregid()
	3. then the child exec()s new process which replaces itself

All of the necessary functions should be under the os module on POSIX
operating systems.


From clp2 at rebertia.com  Thu Jul  2 18:27:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 2 Jul 2009 15:27:23 -0700
Subject: XML(JSON?)-over-HTTP: How to define API?
In-Reply-To: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
References: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
Message-ID: <50697b2c0907021527j6cd6cfb6o734c989b71da77b1@mail.gmail.com>

On Thu, Jul 2, 2009 at 3:06 PM, Allen Fowler<allen.fowler at yahoo.com> wrote:
>
> I have an (in-development) python system that needs to shuttle events / requests around over the network to other parts of itself. ? It will also need to cooperate with a .net application running on yet a different machine.
>
> So, naturally I figured some sort of HTTP event / RPC type of would be a good idea?
>
> Are there any modules I should know about, or guidelines I could read, that could aid me in the design of the API?

http://en.wikipedia.org/wiki/Representational_State_Transfer
(aka REST)

O'Reilly also has a book on the subject.

Cheers,
Chris
-- 
http://blog.rebertia.com


From http  Thu Jul  2 18:29:49 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 15:29:49 -0700
Subject: XML(JSON?)-over-HTTP:  How to define API?
References: <mailman.2520.1246573083.8015.python-list@python.org>
Message-ID: <7xprcipvky.fsf@ruckus.brouhaha.com>

Allen Fowler <allen.fowler at yahoo.com> writes:
> Since I need to work with other platforms, pickle is out...  what
> are the alternatives?  XML? JSON?

json is the easiest to prototype with and is less bureaucratic.  xml
has more serious tools for schema specification and validation etc.
You could start with json and switch later.  As for the rpc mechanism,
using urllib and one of the HTTP server modules is probably simplest.


From charles at declareSub.com  Thu Jul  2 18:30:43 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Thu, 2 Jul 2009 18:30:43 -0400
Subject: XML(JSON?)-over-HTTP:  How to define API?
In-Reply-To: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
References: <115250.26948.qm@web45607.mail.sp1.yahoo.com>
Message-ID: <35DA358F-DFDC-425D-BD68-AFEF2024F537@declareSub.com>


On Jul 2, 2009, at 6:06 PM, Allen Fowler wrote:

>
> I have an (in-development) python system that needs to shuttle  
> events / requests around over the network to other parts of  
> itself.   It will also need to cooperate with a .net application  
> running on yet a different machine.
>
> So, naturally I figured some sort of HTTP event / RPC type of would  
> be a good idea?
>
> Are there any modules I should know about, or guidelines I could  
> read, that could aid me in the design of the API?
>
>
> Thank you,
> :)

I'd suggest the O'Reilly book "RESTful Web Services".

Charles Yeomans


From http  Thu Jul  2 18:32:27 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 15:32:27 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
Message-ID: <7xljn6pvgk.fsf@ruckus.brouhaha.com>

Tim Harig <usernet at ilthio.net> writes:
> That being the case, it might be a good idea either to handle the situation
> and raise an exception or add:
> 
> assert self.lower <= self.higher
> 
> That way an exception will be raised if there is an error somewhere else
> in the code rather then silently passing a possibly incorrect value.

Well, that assert is not right because you have to handle the case
where one of the values is None.  The general sentiment is reasonable
though, if you're concerned that the precondition may not be valid.


From rhodri at wildebst.demon.co.uk  Thu Jul  2 18:38:49 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 02 Jul 2009 23:38:49 +0100
Subject: String to List Question
In-Reply-To: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
References: <564970db0907021505i74a6599dlc9582143343c0701@mail.gmail.com>
Message-ID: <op.uwgo6zj7a8ncjz@gnudebst>

On Thu, 02 Jul 2009 23:05:46 +0100, Hanna Michelsen <hannarosie at gmail.com>  
wrote:

> Hi,
>
> I am brand new to python and I love it, but I've been having some trouble
> with a file parser that I've been working on. It contains lines that  
> start
> with a name and then continue with names, nicknames and phone numbers of
> people associated with that name. I need to create a list of the names of
> people associated with each singular person (the first name in each  
> line).
> Each name/phone number is separated by a tab but if someone doesn't have  
> a
> nickname there are two tabs between their name and number.
>
> I've been trying to figure out how to test for two tabs, skip over these
> people and move onto the next name but I just can't figure out how that  
> will
> work in python.

You might find the csv module in the standard library does a lot of the
hard work for you: http://docs.python.org/library/csv.html

You can define yourself a reader that splits the input on tabs, and
then see how long the rows it returns are.  Something like this
(untested):

import csv

for row in csv.reader(open("phone_numbers.txt", "rb"), delimiter='\t'):
     if len(row) > 1:
         # Do your stuff

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From Russ.Paielli at gmail.com  Thu Jul  2 18:41:56 2009
From: Russ.Paielli at gmail.com (Russ P.)
Date: Thu, 2 Jul 2009 15:41:56 -0700 (PDT)
Subject: Is Psyco good for Python 2.6.1?
Message-ID: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>

I need to speed up some Python code, and I discovered Psyco. However,
the Psyco web page has not been updated since December 2007. Before I
go to the trouble of installing it, does anyone know if it is still
good for Python 2.6.1? Thanks.


From usernet at ilthio.net  Thu Jul  2 18:49:52 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:49:52 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
Message-ID: <kQa3m.3616$Jb1.1642@flpi144.ffdc.sbc.com>

On 2009-07-02, Paul Rubin <http> wrote:
> Tim Harig <usernet at ilthio.net> writes:
>> That being the case, it might be a good idea either to handle the situation
>> and raise an exception or add:
>> assert self.lower <= self.higher
>> That way an exception will be raised if there is an error somewhere else
>> in the code rather then silently passing a possibly incorrect value.
> Well, that assert is not right because you have to handle the case
> where one of the values is None.  The general sentiment is reasonable
> though, if you're concerned that the precondition may not be valid.

Sorry, it worked under 2.5:

2.5	>>> lower = None
2.5	>>> higher = 10
2.5	>>> assert lower <= higher
2.5	>>> assert higher < lower
2.5	Traceback (most recent call last):
2.5	  File "<stdin>", line 1, in <module>
2.5	AssertionError
2.5	>>> higher = -10
2.5	>>> assert lower <= higher
2.5	>>> assert higher < lower
2.5	Traceback (most recent call last):
2.5	  File "<stdin>", line 1, in <module>
2.5	AssertionError

None seems to have been evaluated less then any integer.  The same isn't
true under 3.0:

3.0	>>> lower = None
3.0	>>> higher = 10
3.0	>>> assert lower <= higher
3.0	Traceback (most recent call last):
3.0	  File "<stdin>", line 1, in <module>
3.0	TypeError: unorderable types: NoneType() <= int()

Then it is probably easier to just handle it in the conditionals and raise
an exception manually.


From usernet at ilthio.net  Thu Jul  2 18:56:49 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 02 Jul 2009 22:56:49 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
	<kQa3m.3616$Jb1.1642@flpi144.ffdc.sbc.com>
Message-ID: <RWa3m.3617$Jb1.2835@flpi144.ffdc.sbc.com>

On 2009-07-02, Tim Harig <usernet at ilthio.net> wrote:
> Sorry, it worked under 2.5:
[SNIP]
> None seems to have been evaluated less then any integer.  The same isn't
> true under 3.0:

None seem to have been evaluated less then any non-negative integer
including 0.


From sajmikins at gmail.com  Thu Jul  2 19:04:31 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 16:04:31 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
Message-ID: <f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>

On Jul 2, 4:08?pm, Erik Max Francis <m... at alcyone.com> wrote:
> Simon Forman wrote:
> > Hey I was hoping to get your opinions on a sort of minor stylistic
> > point.
> > These two snippets of code are functionally identical. Which would you
> > use and why?
> > The first one is easier [for me anyway] to read and understand, but
> > slightly less efficient, while the second is [marginally] harder to
> > follow but more efficient.
>
> > ## First snippet
>
> > if self.higher is self.lower is None: return
> > if self.lower is None: return self.higher
> > if self.higher is None: return self.lower
>
> > ## Second snippet
>
> > if self.higher is None:
> > ? ? if self.lower is None:
> > ? ? ? ? return
> > ? ? return self.lower
> > if self.lower is None:
> > ? ? return self.higher
>
> > What do you think?
>
> Explicit is always better, `return None` when that is your intent.
> `return` shouts to the reader, "I want to get out of this function now,
> and no one cares about the return result."
>
> Personally, I only use the one-liner if/else clauses if it's an
> extremely trivial condition, and even then, usually not there. ?(The
> only place I use it consistently is `if __name__ == '__main__':
> main()`.) ?If it's part of something more important that needs
> inspection -- as this obviously does given the questions you've had
> about it, doesn't skip space. ?Newlines are free.
>
> Even when expanding about the first test, there's no reason to do
> chained `if`s. ?One `if` with an `and` works just fine.
>
> Paul Rubin's looked to be the best overall replacement, as the logic
> here looks strangely turned inside out. ?You're obviously looking for
> which one _isn't_ `None`, so write the tests that way. ?It's much easier
> for everyone else (including your potential future self) to follow.
>


Thanks for all the great feedback!

Some notes:

This code is part of a delete() method for a binary tree
implementation. "None" is used to simulate a NULL pointer. In the case
where both children are non-None the code goes on to handle that.

None is a "unitary" or "singleton" value, so "is" is the right
comparison operator to use with it, at least in this "imitation
pointer" usage.

The bare return was used both to preclude executing the rest of the
function and to return None. (I sometimes use "return # None" with
None in a comment to note that the return value is used. Also, I will
put "# return" or "# return None" at the end of a function if the
returning-of-None is important to the implementation of whatever.
I've never used dis.dis() to check the bytecodes, but I wouldn't be
surprised to find that the compiler generated the same bytecode
whether you explicitly state the return or comment it out.)

In any event, as Duncan Booth pointed out, the entire line was
redundant so the issue is somewhat moot in this particular case.

As for one-line control flow statements in python, I usually refrain
but this code wasn't originally meant for public viewing.

Last but not least, the logic may seem backwards but it's actually
correct. If you check for non-None (NULL) -ness and return the thing
you checked, rather than checking for None-ness and returning the
other, the case where both are non-None is not handled correctly.

Thanks again,
~Simon

FWIW, here's the BinaryTree class, the code is in the _delete_me()
method.

from random import random


class BinaryTree:
    '''
    A Binary Tree implementation. Provides:

        get(key) - Return item for key or None.

        insert(key, value) - Insert value under key, replacing old
ones.

        delete(key) - Delete value under key if any.

        keys() - Iterate through the keys in sort order.
        values() - Iterate through the values in sort order.
        items() - Iterate through (key, value) pairs in sort order.

    '''
    def __init__(self, key, value):
        self.key = key
        self.value = value
        self.higher = self.lower = None

    def get(self, key):
        '''
        Return item for key or None.
        '''
        if key == self.key:
            return self.value
        if key < self.key and self.lower is not None:
            return self.lower.get(key)
        if self.higher is not None:
            assert key > self.key
            return self.higher.get(key)

    def insert(self, key, value):
        '''
        Insert value under key, replacing old ones.
        '''
        if key == self.key:
            self.value = value
        elif key < self.key:
            if self.lower is None:
                self.lower = BinaryTree(key, value)
            else:
                self.lower.insert(key, value)
        else:
            assert key > self.key
            if self.higher is None:
                self.higher = BinaryTree(key, value)
            else:
                self.higher.insert(key, value)

    def delete(self, key):
        '''
        Delete value under key if any.
        '''
        if key < self.key and self.lower is not None:
            self.lower = self.lower.delete(key)
        elif key > self.key and self.higher is not None:
            self.higher = self.higher.delete(key)
        elif key == self.key:
            return self._delete_me()
        return self

    def _delete_me(self):
        if self.lower is None: return self.higher
        if self.higher is None: return self.lower

        # Two children...
        try:
            side = self._which_side
        except AttributeError:
            side = bool(int(random() * 2))

        # Alternate sides, should help keep tree balanced.
        self._which_side = not side

        method = self._delete_lower if side else self._delete_higher
        return method()

    def _delete_lower(self):
        next = self.lower
        while next.higher is not None: next = next.higher
        self.key = next.key
        self.value = next.value
        self.lower = self.lower.delete(self.key)
        return self

    def _delete_higher(self):
        next = self.higher
        while next.lower is not None: next = next.lower
        self.key = next.key
        self.value = next.value
        self.higher = self.higher.delete(self.key)
        return self

    def keys(self):
        '''
        Iterate through the keys in sort order.
        '''
        for key, value in self.items():
            yield key

    def values(self):
        '''
        Iterate through the values in sort order.
        '''
        for key, value in self.items():
            yield value

    def items(self):
        '''
        Iterate through (key, value) pairs in sort order.
        '''
        if self.lower is not None:
            for kv in self.lower.items():
                yield kv
        yield self.key, self.value
        if self.higher is not None:
            for kv in self.higher.items():
                yield kv




From barry at python.org  Thu Jul  2 19:10:39 2009
From: barry at python.org (Barry Warsaw)
Date: Thu, 2 Jul 2009 19:10:39 -0400
Subject: Python 3.0 (pinin' for the fjords)
Message-ID: <A94443C0-1CBB-4E54-82C9-CAD8425F822D@python.org>

Now that Python 3.1 is out, it seems there's been some confusion as to  
whether there will be one last Python 3.0 release, i.e. Python 3.0.2.

At the PyCon 2009 language summit it was decided that there will be  
*no* Python 3.0.2.  Python 3.0 is different than all other releases.   
There will be no last maintenance release and no ongoing security  
releases.  Python 3.1 is the replacement for Python 3.0, and it's  
release schedule was accelerated specifically so that production users  
would be able to switch immediately.

If you're using Python 3, you are strongly urged to update to Python  
3.1.  Python 3.1 will be a 'normal' release in that we're making all  
the guarantees that we make for other releases.  It is likely that  
Python 3.2 is 18-24 months away, there will be Python 3.1.x  
maintenance releases, and there will be one last Python 3.1.x release  
after the final release of Python 3.2.

Cheers,
-Barry

-------------- next part --------------
A non-text attachment was scrubbed...
Name: PGP.sig
Type: application/pgp-signature
Size: 849 bytes
Desc: This is a digitally signed message part
URL: <http://mail.python.org/pipermail/python-list/attachments/20090702/a07c4c0c/attachment-0001.sig>

From sajmikins at gmail.com  Thu Jul  2 19:13:47 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 16:13:47 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
Message-ID: <529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com>

On Jul 2, 3:57?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> Duncan Booth wrote:
> > Simon Forman <sajmik... at gmail.com> wrote:
> >> ...
> >> if self.higher is self.lower is None: return
> >> ...
> > As a matter of style however I wouldn't use the shorthand to run two 'is'
> > comparisons together, I'd write that out in full if it was actually needed
> > here.
>
> Speaking only to the style issue, when I've wanted to do something like
> that, I find:
>
> ? ? ? ?if self.higher is None is self.lower:
> ? ? ? ? ? ?...
>
> more readable, by making clear they are both being compared to a
> constant, rather than compared to each other.

I was going to do it that way for aesthetics if nothing else, but in
this particular code "self.higher is self.lower" could only have been
True if they were both None, so the final "is None" was redundant and
I only included it as a "just-in-case" check in case someone someday
used the code in such a way as to assign the same object (not None) to
both self.higher and self.lower...  Totally pointless, I'm sorry to
say.  I'm glad the whole line was redundant really.

> More often, I've used code like:
>
> ? ? ? ?if <expr1> is not None is not <expr2>:
> ? ? ? ? ? ?...
>
> since I am usually working on non-defaulting cases in the body.
> I find the form above simpler to read than:
>
> ? ? ? ?if <expr1> is not None and <expr2> is not None:
> ? ? ? ? ? ?...
>
> I do draw the line at two, though, and with three or more I'll
> paren-up a list of parallel comparisons:
>
> ? ? ? ?if (<expr1> is not None
> ? ? ? ? ?and <expr2> is not None
> ? ? ? ? ?and <expr3> is not None):
> ? ? ? ? ? ?...
>
> --Scott David Daniels
> Scott.Dani... at Acm.Org



From mensanator at aol.com  Thu Jul  2 20:34:31 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 2 Jul 2009 17:34:31 -0700 (PDT)
Subject: Is Psyco good for Python 2.6.1?
References: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
Message-ID: <e4fe73ac-fa53-4614-b5b5-6ce489b3062a@c36g2000yqn.googlegroups.com>

On Jul 2, 5:41?pm, "Russ P." <Russ.Paie... at gmail.com> wrote:
> I need to speed up some Python code, and I discovered Psyco. However,
> the Psyco web page has not been updated since December 2007. Before I
> go to the trouble of installing it, does anyone know if it is still
> good for Python 2.6.1? Thanks.

Go back to the web site and look at the download page.

Usually, the download page will list various versions
to use with various Python versions. If it lists a
2.4 version, a 2.5 version, but no 2.6 version, most likely
the authors haven't yet made a 2.6 version so you're SOL.

Even that isn't guaranteed to always work. For instance,
the authors of the smpy module didn't think they needed
a seperate 2.6 version (and didn't make any effort to
actually try it 2.6). Turned out to be dead wrong on that
and had to scramble to release a fix.


From http  Thu Jul  2 20:57:15 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 17:57:15 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
	<kQa3m.3616$Jb1.1642@flpi144.ffdc.sbc.com>
Message-ID: <7x8wj61t3o.fsf@ruckus.brouhaha.com>

Tim Harig <usernet at ilthio.net> writes:
> > Well, that assert is not right because you have to handle the case
> > where one of the values is None...  
> Sorry, it worked under 2.5:

Well, it didn't crash under 2.5.  Whether the result was correct
is a different question.  

> None seems to have been evaluated less then any integer.  The same isn't
> true under 3.0:

But the original code didn't specify the non-None values to be
integers.  Really, it's unwise to rely on an ordering relation between
None and values of arbitrary other types, unless supportable by a
clear specification, but even then, it's a code smell.

> 3.0	TypeError: unorderable types: NoneType() <= int()

That is far preferable to what 2.x does.


From rylesny at gmail.com  Thu Jul  2 21:03:59 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 18:03:59 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<h2i35q$mp4$01$1@news.t-online.com>
Message-ID: <5a6891ba-bb93-41ab-8ba5-acb23bde3ae9@a7g2000yqk.googlegroups.com>

> You can go ahead and implement a __del__() method. It will often work in
> CPython, but you get no guarantees, especially when you have reference
> cycles and with other Python implementations that don't use refcounting.

And for resources whose lifetime is greater than your process (e.g. a
file), you can also use the atexit module to help ensure they are
cleaned/reclaimed at shutdown. One way to do this is to maintain a
weak dictionary (from the weakref module) to your objects and install
a handler which iterates this. This is useful for not only dealing
with reference cycles, but for objects which may exist at the time the
interpreter exits. These may not be deleted.

http://docs.python.org/reference/datamodel.html#object.__del__


From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:37 -0300
Subject: stringio+tarfile
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <op.uwgt4tlux6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 17:57:49 -0300, superpollo <user at example.net> escribi?:

> why the following does not work? can you help me correct (if possible)?

Explain "does not work" please. Does it raise an exception? Which one?
Please post the complete traceback. You don't get the expected result?
Tell us what did you expect and what you actually get. If you provide this
information, it's a lot easier for people to look at your problem and
eventually find a solution.

Fortunately my crystall ball is back from the repair shop and I can guess
that you want to create a tar file in memory, and add some content from a
memory buffer too, right?
I didn't run your code but I can see two problems:

>        5 tf = StringIO.StringIO()
>        6 tar = tarfile.open(tf , "w")

The first argument to tarfile.open is the *name* of the file to
open/create. In this case you don't have a real file, but a StringIO
object; use the fileobj argument instead: tarfile.open(fileobj=tf,
mode="w")
See http://docs.python.org/library/tarfile.html#tarfile.open

>        7 for name in [sf1 , sf2]:
>        8     tar.add(name)

The add method takes the *name* of a file to add to the archive. Again,
you don't have a real file to add; try the addfile method instead.
See http://docs.python.org/library/tarfile.html#tarfile.TarFile.add


-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:42 -0300
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
	<25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>
	<Zua3m.3615$Jb1.1092@flpi144.ffdc.sbc.com>
Message-ID: <op.uwguqbqjx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 19:27:05 -0300, Tim Harig <usernet at ilthio.net>
escribi?:
> On 2009-07-02, sanket <sanket.s.patel at gmail.com> wrote:
>>> sanket wrote:

>>> > I am trying to use python's subprocess module to launch a process.
>>> > but in order to do that I have to change the user.
>> I am using python 2.4 on centos.
>
> I have never done this in python; but, using the normal system calls in C
> the process is basically:
> 	
> 	1. fork() a  new process
> 	2. the child process changes its user id with setreuid() and
> 		possibly its group id with setregid()
> 	3. then the child exec()s new process which replaces itself
>
> All of the necessary functions should be under the os module on POSIX
> operating systems.

How to do that using the subprocess module: write a function for item (2)
above and pass it as the preexec_fn argument to Popen. preexec_fn is
executed after fork() and before exec()

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:45 -0300
Subject: dealloc function in python extend c module
References: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
	<8599A253-D2C9-4EE4-AF4F-AEF658BA2033@semanchuk.com>
Message-ID: <op.uwgv3ywwx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 14:22:53 -0300, Philip Semanchuk
<philip at semanchuk.com> escribi?:
> On Jul 2, 2009, at 2:11 AM, Shen, Yu-Teh wrote:
>
>> I create my extend type something like  
>> http://www.python.org/doc/current/extending/newtypes.html.
>> And my type has a member which is a pointer point to my allocate
>> memory ( no ref count).
>> ex:
>> ---------------------------------------------------
>> typedef struct {
>>    PyObject_HEAD
>>    /* Type-specific fields go here. */
>>    mytype *p;
>> } noddy_NoddyObject;
>>
>> And i write dealloc function like this:
>> ---------------------------------------------------
>> static void
>> Noddy_dealloc(Noddy* self)
>> {
>>    delete p;
>>    self->ob_type->tp_free((PyObject*)self);
>> }
>>
>> And I found it's strange that it didn't call dealloc when there is no
>> reference.

And you set the tp_dealloc field in the type structure to Noddy_dealloc,
did you?

>> ex:
>> a = Noddy()
>> b = a
>> del a
>> del b
>> # i think there is no ref to the object, and it should call dealloc
>> but it didn't call!!!

You can use sys.getrefcount(a) to check how many references it has.
Remember that it returns one more than the value you expect (because the
function itself holds a temporary reference to its argument)

> Hi Shen,
> I'm no expert on Python memory management, but since no once else has  
> answered your question I'll tell you what I *think* is happening.
>
> Python doesn't delete objects as soon as they're dereferenced.

Nope. CPython *does* destroy objects as soon as their reference count
reaches zero. It does not rely on garbage collection for that.

> It merely marks them as safe for garbage collection (GC). If GC never  
> happens (and it might not in a small test program), your dealloc  
> function won't run.

The garbage collector is only used to recover memory from object cycles
(in the CPython implementation; Jython *does* use garbage collection for
"normal" object destruction too)

> Now some more knowledgeable person will probably correct me. =)

And now some more knowledgeable person will probably correct me. =)

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul  2 21:28:48 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 02 Jul 2009 22:28:48 -0300
Subject: A question about fill_free_list(void) function
References: <169b5d83-696b-44d4-8816-0522844d3fe4@h8g2000yqm.googlegroups.com>
	<mailman.2439.1246489507.8015.python-list@python.org>
	<9829f925-0091-4bc3-8f12-de83f7aba8e6@j32g2000yqh.googlegroups.com>
	<h2htjt$t6e$00$1@news.t-online.com>
	<7c8e96a1-cbb2-4036-9aa1-1ecdfd84cca8@j32g2000yqh.googlegroups.com>
Message-ID: <op.uwgwwsx8x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 02 Jul 2009 07:55:42 -0300, Pedram <pm567426 at gmail.com> escribi?:
> On Jul 2, 1:11?pm, Peter Otten <__pete... at web.de> wrote:

>> [snip explanation of strange pointer manipulations in the C code of the  
>> integer type]

> Oh, I got it! What a wonderful implementation! :o

Well, I would not say it's "wonderful"...
The wonderful part is that all those nasty tricks are only there, hidden
  from us poor mortals, so we can focus on writing nice and elegant Python
code instead :)

-- 
Gabriel Genellina



From http  Thu Jul  2 21:30:07 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 18:30:07 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
Message-ID: <7x4otu1rkw.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> This code is part of a delete() method for a binary tree
> implementation. "None" is used to simulate a NULL pointer. In the case
> where both children are non-None the code goes on to handle that.
> 
> None is a "unitary" or "singleton" value, so "is" is the right
> comparison operator to use with it, at least in this "imitation
> pointer" usage.

Yes, but the concept of null pointers is considered kludgy these days.
One alternative is to represent an empty node as an empty list [], and
a node with value x as the 1-element list [x].  That incurs some
storage overhead, but all the case by case checking in your comparison
function goes away:

   return (self.higher + self.lower)[:1]

> I've never used dis.dis() to check the bytecodes, but I wouldn't be
> surprised to find that the compiler generated the same bytecode
> whether you explicitly state the return or comment it out.)

I really wouldn't worry about this.  Python is so slow no matter what
you do, that 1 more no-op bytecode won't matter.

> Last but not least, the logic may seem backwards but it's actually
> correct. If you check for non-None (NULL) -ness and return the thing
> you checked, rather than checking for None-ness and returning the
> other, the case where both are non-None is not handled correctly.

The code you posted didn't return anything if both values were non-None.

As for checking for None-ness vs. non-None-ness, sure, the two are
logically equivalent, but I think checking for non-None expresses the
algorithm more clearly.

> FWIW, here's the BinaryTree class, ...
>     A Binary Tree implementation. Provides:
>         get(key) - Return item for key or None.

I'm sorry but I find that class rather ugly.  The code would be a lot
smaller and have fewer corner cases with a different data
representation.


From rylesny at gmail.com  Thu Jul  2 22:10:18 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 19:10:18 -0700 (PDT)
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com> 
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net> 
	<mailman.2478.1246529340.8015.python-list@python.org>
Message-ID: <1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>

On Jul 2, 6:10?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> En Wed, 01 Jul 2009 12:49:31 -0300, Scott David Daniels ?
> <Scott.Dani... at acm.org> escribi?:
> > These loops work well with the two-argument version of iter,
> > which is easy to forget, but quite useful to have in your bag
> > of tricks:
>
> > ? ? ?def convert(in_queue, out_queue):
> > ? ? ? ? ?for row in iter(in_queue.get, None):
> > ? ? ? ? ? ? ?# ... convert row
> > ? ? ? ? ? ? ?out_queue.put(converted_line)
>
> Yep, I always forget about that variant of iter() -- very handy!

Yes, at first glance using iter() here seems quite elegant and clever.
You might even pat yourself on the back, or treat yourself to an ice
cream cone, as I once did. There is one subtle distinction, however.
Please allow me to demonstrate.

>>> import Queue
>>>
>>> queue = Queue.Queue()
>>>
>>> queue.put(1)
>>> queue.put("la la la")
>>> queue.put(None)
>>>
>>> list(iter(queue.get, None))
[1, 'la la la']
>>>
>>> # Cool, it really works! I'm going to change all my old code to use this... new and *improved*
...
>>> # And then one day your user inevitably does something like this.
...
>>> class A(object):
...     def __init__(self, value):
...         self.value = value
...
...     def __eq__(self, other):
...         return self.value == other.value
...
>>> queue.put(A(1))
>>> queue.put(None)
>>>
>>> # And then this happens inside your 'generic' code (which probably even passed your unit tests).
...
>>> list(iter(queue.get, None))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 5, in __eq__
AttributeError: 'NoneType' object has no attribute 'value'
>>>
>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which iter() will do. Sorry guys!

Please don't let this happen to you too ;)


From http  Thu Jul  2 22:20:03 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 19:20:03 -0700
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
Message-ID: <7xfxdev770.fsf@ruckus.brouhaha.com>

ryles <rylesny at gmail.com> writes:
> >>> # Oh... yeah. I really *did* want 'is None' and not '== None'
> >>> which iter() will do. Sorry guys!
> 
> Please don't let this happen to you too ;)

None is a perfectly good value to put onto a queue.  I prefer
using a unique sentinel to mark the end of the stream:

   sentinel = object()


From rylesny at gmail.com  Thu Jul  2 22:23:54 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 19:23:54 -0700 (PDT)
Subject: What are the limitations of cStringIO.StringIO() ?
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com> 
	<mailman.2455.1246494464.8015.python-list@python.org>
Message-ID: <5354b682-1f7e-4274-96e6-b51a3556e931@h11g2000yqb.googlegroups.com>

This reminds me. Would anyone object to adding a sentence to
http://docs.python.org/library/stringio.html#module-cStringIO just to
mention that attributes cannot be added to a cStringIO, like such:

% import cStringIO, StringIO
% StringIO.StringIO().value = 1
% cStringIO.StringIO().value = 1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'cStringIO.StringO' object has no attribute 'value'


From bearophileHUGS at lycos.com  Thu Jul  2 22:34:50 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 2 Jul 2009 19:34:50 -0700 (PDT)
Subject: Is Psyco good for Python 2.6.1?
References: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
Message-ID: <c8b3d84a-5975-4912-a757-b613c2973a63@j32g2000yqh.googlegroups.com>

Russ P.:

Python works well to me on Python 2.6+, on Windows. You can find a
compiled version too, around.

Bye,
bearophile



From davea at ieee.org  Thu Jul  2 22:35:59 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 02 Jul 2009 22:35:59 -0400
Subject: stringio+tarfile
In-Reply-To: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <4A4D6E8F.1000506@ieee.org>

superpollo wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">why the 
> following does not work? can you help me correct (if possible)?
>
>       1 import tarfile
>       2 import StringIO
>       3 sf1 = StringIO.StringIO("one\n")
>       4 sf2 = StringIO.StringIO("two\n")
>       5 tf = StringIO.StringIO()
>       6 tar = tarfile.open(tf , "w")
>       7 for name in [sf1 , sf2]:
>       8     tar.add(name)
>       9 print tf
>      10 sf1.close()
>      11 sf2.close()
>      12 tf.close()
>      13 tar.close()
>
> tia
>
> </div>
>
Couldn't you have given a clue as to what doesn't work?   What version 
of Python are you using, and on what platform?  Do you get an error 
message, or are the results unreasonable? Details please.

First problem I see is all those numbers before the lines.  That's not 
valid python.

Assuming that was a transcription error, we get to some other problems.

tarfile.open() first argument is a filename, and you're passing it a 
Stringio object.  Not the same at all.  Fortunately, the Stringio should 
work as the third parameter, so you can change this line to
   tarfile.open(None, "w", tf)


Similarly tar.add() takes a filename as a parameter, and you're trying 
to pass another Stringio.  That's not a possible argument to the add() 
method at all.  Try tar.addfile()

I stopped at this point.  Maybe somebody else can help, after you fill 
in a few details.



From sajmikins at gmail.com  Thu Jul  2 22:52:10 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 22:52:10 -0400
Subject: What are the limitations of cStringIO.StringIO() ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
Message-ID: <50f98a4c0907021952y50bea866heb69ed4cff52d590@mail.gmail.com>

On Wed, Jul 1, 2009 at 7:48 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
> Hi,
>
> I think I'm up against a limitation in cStringIO.StringIO(), but could not
> find any clues on the web, especially not in
> http://docs.python.org/library/stringio.html.
>
> What I have is the following function:
>
> ??? def concatenate_files(self,filename_array):
> ??????? import types
>
> ??????? f = cStringIO.StringIO()
> ??????? for filename in filename_array:
> ??????????? log_stream = LogStream(filename)
> ??????????? if not isinstance(log_stream, types.NoneType):
> ??????????????? try:
> ??????????????????? string_ = log_stream.input_file.read()
> ??????????????? except AttributeError, e:
> ??????????????????????? sys.stderr.write("AttributeError: "+str(e)+"\n")
> ??????????????????????? sys.stderr.write("log_stream:
> "+str(log_stream)+"\n")
> ??????????? else:
> ??????????????? return(None)
>
> ??????????? f.write(string_)
> ??????? return (f)
>
> And, when the list of files?- in filename_array - is pointing to long/large
> enough files, I get the exception:
>
> Traceback (most recent call last):
> ? File "svm_ts_tool_in_progress.py", line 244, in OnSelectCell
> ??? self.InspectorViewController(row,col)
> ? File "svm_ts_tool_in_progress.py", line 1216, in InspectorViewController
> ??? self.InspectorePaneGetRecords(self.req_table, rec)
> ? File "svm_ts_tool_in_progress.py", line 1315, in InspectorePaneGetRecords
> ??? log_stream =
> ConcatenatedLogStream(self.events_dict[req_table]["db_dict"].keys())
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 31, in
> __init__
> ??? self.input_file = self.concatenate_files(filename_array)
> ? File "c:\Documents and
> Settings\rbarak\rbarak_devel\dpm16\ConcatenatedLogStream.py", line 47, in
> concatenate_files
> ??? string_ = log_stream.input_file.read()
> MemoryError
>
> Anyone knows whet's the limitation on cStringIO.StringIO() objects ?
> Could you suggest a better way to create a string that contains the
> concatenation of several big files ?
>
> Thanks,
> Ron.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>

MemoryError means you're out of memory.  Try using the operating
system commands for file concatenation, i.e. "cat" on *nix, dunno how
on windows.  Or just do whatever it is you're doing in a different way
that doesn't require having all the data in memory at once.

Also, this:

not isinstance(log_stream, types.NoneType)

should just be this:

log_stream is not None

and return is not a function, leave out the ()'s around the expression
you're returning, and if you're returning None, you can leave out the
None as it is the default return value anyway.

Generally speaking don't do module imports in functions.


From benjamin at python.org  Thu Jul  2 22:54:31 2009
From: benjamin at python.org (Benjamin Peterson)
Date: Fri, 3 Jul 2009 02:54:31 +0000 (UTC)
Subject: What are the limitations of cStringIO.StringIO() ?
References: <7F0503CD69378F49BE0DC30661C6CCF6701A2600@enbmail01.lsi.com>
	<mailman.2455.1246494464.8015.python-list@python.org>
	<5354b682-1f7e-4274-96e6-b51a3556e931@h11g2000yqb.googlegroups.com>
Message-ID: <loom.20090703T025406-577@post.gmane.org>

ryles <rylesny <at> gmail.com> writes:

> 
> This reminds me. Would anyone object to adding a sentence to
> http://docs.python.org/library/stringio.html#module-cStringIO just to
> mention that attributes cannot be added to a cStringIO, like such:

That's true of almost all types that are implemented in C.






From rylesny at gmail.com  Thu Jul  2 22:55:19 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 19:55:19 -0700 (PDT)
Subject: Adding an object to the global namespace through " f_globals" is 
	that allowed ?
References: <4A4BC22D.70502@gmail.com>
	<mailman.2467.1246512323.8015.python-list@python.org>
Message-ID: <4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>

On Jul 2, 1:25 am, Terry Reedy <tjre... at udel.edu> wrote:
> > The next statement works,
> > but I'm not sure if it will have any dramatical side effects,
> > other than overruling a possible object with the name A
>
> > def some_function ( ...) :
> >      A = object ( ...)
> >      sys._getframe(1).f_globals [ Name ] = A
>
> global name
> name = A
>
> or is name is a string var
> globals()[name] = A

It wasn't explicit, but I think Stef meant that the global should be
added to the caller's environment, which was the reason for
sys._getframe().

Is this environment only intended for interactive use? I wonder if you
might just set things up
in a PYTHONSTARTUP script instead.


From schickb at gmail.com  Thu Jul  2 22:56:50 2009
From: schickb at gmail.com (schickb)
Date: Thu, 2 Jul 2009 19:56:50 -0700 (PDT)
Subject: Sequence splitting
Message-ID: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>

I have fairly often found the need to split a sequence into two groups
based on a function result. Much like the existing filter function,
but returning a tuple of true, false sequences. In Python, something
like:

def split(seq, func=None):
    if func is None:
        func = bool
    t, f = [], []
    for item in seq:
        if func(item):
            t.append(item)
        else:
            f.append(item)
    return (t, f)

The discussion linked to below has various approaches for doing this
now, but most traverse the sequence twice and many don't apply a
function to spit the sequence.
http://stackoverflow.com/questions/949098/python-split-a-list-based-on-a-condition

Is there any interest in a C implementation of this? Seems too trivial
to write a PEP, so I'm just trying to measure interest before diving
in. This wouldn't really belong in intertool. Would it be best
implemented as a top level built-in?

-Brad


From alan.isaac at gmail.com  Thu Jul  2 22:59:51 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 02:59:51 GMT
Subject: Python 3.0 (pinin' for the fjords)
In-Reply-To: <mailman.2526.1246576243.8015.python-list@python.org>
References: <mailman.2526.1246576243.8015.python-list@python.org>
Message-ID: <Hue3m.534$P5.391@nwrddc02.gnilink.net>

Using the 3.1 Windows installer, I chose that I did not
want the extensions registered, and the installer
unregistered the .py and .pyw extensions (which I had wanted
to keep associated with Python 2.6).

Is this intentional?

Alan Isaac

PS I already fixed the problem.  My question
is about intent.


From rylesny at gmail.com  Thu Jul  2 23:09:25 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 20:09:25 -0700 (PDT)
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com> 
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net> 
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
Message-ID: <c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>

On Jul 2, 10:20?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> ryles <ryle... at gmail.com> writes:
> > >>> # Oh... yeah. I really *did* want 'is None' and not '== None'
> > >>> which iter() will do. Sorry guys!
>
> > Please don't let this happen to you too ;)
>
> None is a perfectly good value to put onto a queue. ?I prefer
> using a unique sentinel to mark the end of the stream:
>
> ? ?sentinel = object()

I agree, this is cleaner than None. We're still in the same boat,
though, regarding iter(). Either it's 'item == None' or 'item == object
()', and depending on the type, __eq__ can introduce some avoidable
risk.

FWIW, even object() has its disadvantages. Namely, it doesn't work for
multiprocessing.Queue which pickles and unpickles, thus giving you a
new object. One way to deal with this is to define a "Stopper" class
and type check objects taken from the queue. This is not news to
anyone who's worked with multiprocessing.Queue, though.


From tn.pablo at gmail.com  Thu Jul  2 23:10:14 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 2 Jul 2009 22:10:14 -0500
Subject: Sequence splitting
In-Reply-To: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
Message-ID: <fdd00b510907022010g34958774p77f68c4cc35b19c9@mail.gmail.com>

On Thu, Jul 2, 2009 at 21:56, schickb<schickb at gmail.com> wrote:
> I have fairly often found the need to split a sequence into two groups
> based on a function result. Much like the existing filter function,
> but returning a tuple of true, false sequences. In Python, something
> like:
>
> def split(seq, func=None):
> ? ?if func is None:
> ? ? ? ?func = bool
> ? ?t, f = [], []
> ? ?for item in seq:
> ? ? ? ?if func(item):
> ? ? ? ? ? ?t.append(item)
> ? ? ? ?else:
> ? ? ? ? ? ?f.append(item)
> ? ?return (t, f)
>
> The discussion linked to below has various approaches for doing this
> now, but most traverse the sequence twice and many don't apply a
> function to spit the sequence.
> http://stackoverflow.com/questions/949098/python-split-a-list-based-on-a-condition
>
> Is there any interest in a C implementation of this? Seems too trivial
> to write a PEP, so I'm just trying to measure interest before diving
> in. This wouldn't really belong in intertool. Would it be best
> implemented as a top level built-in?
>
> -Brad
> --
> http://mail.python.org/mailman/listinfo/python-list
>

This sounds like it belongs to the python-ideas list.  I suggest
posting there for better feedback, since the core developers check
that list more often than this one.


-- 
Pablo Torres N.


From http  Thu Jul  2 23:14:24 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 20:14:24 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
Message-ID: <7xzlbm5ugf.fsf@ruckus.brouhaha.com>

schickb <schickb at gmail.com> writes:
> def split(seq, func=None):
>     if func is None:
>         func = bool
>     t, f = [], []
>     for item in seq:
>         if func(item):
>             t.append(item)
>         else:
>             f.append(item)
>     return (t, f)

untested:

   def split(seq, func=bool):
      xs = zip(seq, itertools.imap(func, seq))
      t = list(x for (x,y) in xs if y)
      f = list(x for (x,y) in xs if not y)
      return (t, f)


From http  Thu Jul  2 23:15:40 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 20:15:40 -0700
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
Message-ID: <7xvdma5ueb.fsf@ruckus.brouhaha.com>

ryles <rylesny at gmail.com> writes:
> > ? ?sentinel = object()
> 
> I agree, this is cleaner than None. We're still in the same boat,
> though, regarding iter(). Either it's 'item == None' or 'item == object ()'

Use "item is sentinel".  


From tn.pablo at gmail.com  Thu Jul  2 23:17:32 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 2 Jul 2009 20:17:32 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
Message-ID: <3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>

On Jul 2, 9:56?pm, schickb <schi... at gmail.com> wrote:
> I have fairly often found the need to split a sequence into two groups
> based on a function result. Much like the existing filter function,
> but returning a tuple of true, false sequences. In Python, something
> like:
>
> def split(seq, func=None):
> ? ? if func is None:
> ? ? ? ? func = bool
> ? ? t, f = [], []
> ? ? for item in seq:
> ? ? ? ? if func(item):
> ? ? ? ? ? ? t.append(item)
> ? ? ? ? else:
> ? ? ? ? ? ? f.append(item)
> ? ? return (t, f)
>
> The discussion linked to below has various approaches for doing this
> now, but most traverse the sequence twice and many don't apply a
> function to spit the sequence.http://stackoverflow.com/questions/949098/python-split-a-list-based-o...
>
> Is there any interest in a C implementation of this? Seems too trivial
> to write a PEP, so I'm just trying to measure interest before diving
> in. This wouldn't really belong in intertool. Would it be best
> implemented as a top level built-in?
>
> -Brad

This sounds like it belongs to the python-ideas list.  I suggest
posting there for better feedback, since the core developers check
that list more often than this one.



From philip at semanchuk.com  Thu Jul  2 23:17:35 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 2 Jul 2009 23:17:35 -0400
Subject: dealloc function in python extend c module
In-Reply-To: <op.uwgv3ywwx6zn5v@lepton.softlabbsas.com.ar>
References: <291af939-28c0-441f-ab4e-7b3cf5867a83@d32g2000yqh.googlegroups.com>
	<8599A253-D2C9-4EE4-AF4F-AEF658BA2033@semanchuk.com>
	<op.uwgv3ywwx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <AE97376F-ED7D-48D8-9543-4EB109C673AC@semanchuk.com>


On Jul 2, 2009, at 9:28 PM, Gabriel Genellina wrote:

> En Thu, 02 Jul 2009 14:22:53 -0300, Philip Semanchuk
> <philip at semanchuk.com> escribi?:
>>
>> Hi Shen,
>> I'm no expert on Python memory management, but since no once else  
>> has answered your question I'll tell you what I *think* is happening.
>>
>> Python doesn't delete objects as soon as they're dereferenced.
>
> Nope. CPython *does* destroy objects as soon as their reference count
> reaches zero. It does not rely on garbage collection for that.
>
>> It merely marks them as safe for garbage collection (GC). If GC  
>> never happens (and it might not in a small test program), your  
>> dealloc function won't run.
>
> The garbage collector is only used to recover memory from object  
> cycles
> (in the CPython implementation; Jython *does* use garbage collection  
> for
> "normal" object destruction too)
>
>> Now some more knowledgeable person will probably correct me. =)

Wow, that last part was the only part I got right. =) Thanks for  
straightening me out, Gabriel.





From gagsl-py2 at yahoo.com.ar  Thu Jul  2 23:47:54 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 03 Jul 2009 00:47:54 -0300
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
	<7xvdma5ueb.fsf@ruckus.brouhaha.com>
Message-ID: <op.uwg3h4pdx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 00:15:40 -0300, <//phr.cx at nospam.invalid>> escribi?:

> ryles <rylesny at gmail.com> writes:
>> > ? ?sentinel = object()
>>
>> I agree, this is cleaner than None. We're still in the same boat,
>> though, regarding iter(). Either it's 'item == None' or 'item == object  
>> ()'
>
> Use "item is sentinel".

We're talking about the iter() builtin behavior, and that uses ==  
internally.

It could have used an identity test, and that would be better for this  
specific case. But then iter(somefile.read, '') wouldn't work. A  
compromise solution is required; since one can customize the equality test  
but not an identity test, the former has a small advantage. (I don't know  
if this was the actual reason, or even if this really was a concious  
decision, but that's why *I* would choose == to test against the sentinel  
value).

-- 
Gabriel Genellina



From sajmikins at gmail.com  Thu Jul  2 23:54:18 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 20:54:18 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
Message-ID: <a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>

On Jul 2, 9:30?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> writes:
> > This code is part of a delete() method for a binary tree
> > implementation. "None" is used to simulate a NULL pointer. In the case
> > where both children are non-None the code goes on to handle that.
>
> > None is a "unitary" or "singleton" value, so "is" is the right
> > comparison operator to use with it, at least in this "imitation
> > pointer" usage.
>
> Yes, but the concept of null pointers is considered kludgy these days.

Seriously? "kludgy"?  (I really AM getting old.)

Well I wouldn't know, I've been fortunate enough to program mostly in
python for over half a decade now and None and 0 are as close as I've
gotten to NULL in a long time.

> One alternative is to represent an empty node as an empty list [], and
> a node with value x as the 1-element list [x]. ?That incurs some
> storage overhead, but all the case by case checking in your comparison
> function goes away:
>
> ? ?return (self.higher + self.lower)[:1]

Heh, program LISP much? :]

That sounds very interesting, but I'm only writing a BTree to then use
it to play with "persistent data structures" and the models I'm using
are based on pointer code.  I wouldn't want to try to re-implement
them on top of a different "architecture", at least not at first.

> > I've never used dis.dis() to check the bytecodes, but I wouldn't be
> > surprised to find that the compiler generated the same bytecode
> > whether you explicitly state the return or comment it out.)
>
> I really wouldn't worry about this. ?Python is so slow no matter what
> you do, that 1 more no-op bytecode won't matter.

I'm not worried about it at all. In fact, I'm pretty sure the compiler
handles it for me as well as I could want or expect it to.

"A Computer's Perspective on Moore's Law: Humans are getting more
expensive at an exponential rate." - Mark Miller
http://www.caplet.com/adages.html

Python may be slow to execute but it's fast to write. (And write
well.)  ;]

> > Last but not least, the logic may seem backwards but it's actually
> > correct. If you check for non-None (NULL) -ness and return the thing
> > you checked, rather than checking for None-ness and returning the
> > other, the case where both are non-None is not handled correctly.
>
> The code you posted didn't return anything if both values were non-None.

Yep, it was just a snippet, just the part I wanted feedback on.

> As for checking for None-ness vs. non-None-ness, sure, the two are
> logically equivalent, but I think checking for non-None expresses the
> algorithm more clearly.

In this particular case it's somewhat more elegant (IMO) to check "is
None".

> > FWIW, here's the BinaryTree class, ...
> > ? ? A Binary Tree implementation. Provides:
> > ? ? ? ? get(key) - Return item for key or None.
>
> I'm sorry but I find that class rather ugly. ?The code would be a lot
> smaller and have fewer corner cases with a different data
> representation.

Um, thanks?  Seriously though, care to put your money where your mouth
is? I'd be interested to see a BTree implemented as you indicated
above.

Pointer code in python is silly in general, since you're only
imitating real pointers with attributes (i.e. instance dicts) anyway.
As I said above, I'm faking it with python to explore persistent data
structures and the models I've found so far are pointer-based.  I'm
sure there are better (i.e. faster) ways to get the same (or
sufficiently similar) behavior in a more "pythonic" fashion. (for
example, to maintain a sorted sequence under insertion I'd use a list
and the bisect module, and so on.)

Reminds me, a few years back I implemented Knuth's "Dancing Links"
algorithm in python for a Sudoku solver.  It uses a kind of grid of
doubly-linked lists to store information about the search space and to
traverse that space to resolve an answer.  The algorithm takes
advantage of the fact that allocated nodes persisted in memory even
when completely unlinked from the "surrounding" lists.  You unlinked
and re-linked the nodes/lists in a certain pattern to search and
backtrack the search space.  It's more than I can explain here. Really
elegant algorithm.

The point is in python you had to put ALL the nodes into a storage
structure just to prevent them disappearing while unlinked from the
"head" of the grid.

Regards,
~Simon


From schickb at gmail.com  Thu Jul  2 23:55:12 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 20:55:12 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
Message-ID: <08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>

On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> schickb <schi... at gmail.com> writes:
> > def split(seq, func=None):
> > ? ? if func is None:
> > ? ? ? ? func = bool
> > ? ? t, f = [], []
> > ? ? for item in seq:
> > ? ? ? ? if func(item):
> > ? ? ? ? ? ? t.append(item)
> > ? ? ? ? else:
> > ? ? ? ? ? ? f.append(item)
> > ? ? return (t, f)
>
> untested:
>
> ? ?def split(seq, func=bool):
> ? ? ? xs = zip(seq, itertools.imap(func, seq))
> ? ? ? t = list(x for (x,y) in xs if y)
> ? ? ? f = list(x for (x,y) in xs if not y)
> ? ? ? return (t, f)

In my testing that is 3.5x slower than the original solution (and less
clear imo). I fixed my version to take a bool default. Either way, I'm
not really looking for additional ways to do this in Python unless
I've totally missed something. What I am considering is writing it in
C, much like filter.

-Brad


From http  Thu Jul  2 23:55:12 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 20:55:12 -0700
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
	<7xvdma5ueb.fsf@ruckus.brouhaha.com>
	<mailman.2538.1246592805.8015.python-list@python.org>
Message-ID: <7xhbxu4dzz.fsf@ruckus.brouhaha.com>

"Gabriel Genellina" <gagsl-py2 at yahoo.com.ar> writes:
> We're talking about the iter() builtin behavior, and that uses ==
> internally.

Oh, I see.  Drat.

> It could have used an identity test, and that would be better for this
> specific case. But then iter(somefile.read, '') wouldn't work.

Yeah, it should allow supplying a predicate instead of using == on
a value.  How about (untested):

   from itertools import *
   ...
   for row in takewhile(lambda x: x is sentinel,
                         starmap(in_queue.get, repeat(()))): 
      ...


From schickb at gmail.com  Thu Jul  2 23:56:03 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 20:56:03 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
Message-ID: <d72a0e75-5dc4-4c08-8ae2-5b5dce11d531@m7g2000prd.googlegroups.com>

On Jul 2, 8:17?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
> On Jul 2, 9:56?pm, schickb <schi... at gmail.com> wrote:
>
> > I have fairly often found the need to split a sequence into two groups
> > based on a function result.
>
> This sounds like it belongs to the python-ideas list. ?I suggest
> posting there for better feedback, since the core developers check
> that list more often than this one.

Thanks, I didn't know about that list.


From rylesny at gmail.com  Thu Jul  2 23:56:52 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 20:56:52 -0700 (PDT)
Subject: multiprocessing: pool with blocking queue
References: <80eaa77f-c78a-4549-8e95-29292b77b280@n21g2000vba.googlegroups.com>
Message-ID: <c9e58a82-d371-43bb-b6d5-334e8aa54041@s9g2000yqd.googlegroups.com>

On Jul 2, 11:09?am, masher <vertesp... at gmail.com> wrote:
> My questions, then, is: Is there a more elegant/pythonic way of doing
> what I am trying to do with the current Pool class?

Another thing you might try is to subclass Pool and add an apply_async
() wrapper which would wait for _taskqueue.qsize() to reach the
desired size. You would probably do this wait in a loop with a small
sleep. This approach would avoid needing a second Queue, but you would
also add some delay to your producer due to the sleep (something
you're not currently worried about). The minimum sleep may be
something like 1 ms (it's really system dependent), but the time it
takes for a thread blocked on a mutex to wake up is often more on the
order of microseconds, which you have with your blocking queue.

I doubt this offers you much satisfaction, though.

> If the verdict is no, I'll be happy to file a bug report.

Yeah, I think it's a worth a try.


From http  Fri Jul  3 00:08:02 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 21:08:02 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
Message-ID: <7xhbxu4del.fsf@ruckus.brouhaha.com>

Brad <schickb at gmail.com> writes:

> On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> > schickb <schi... at gmail.com> writes:
> > > def split(seq, func=None):
> > > ? ? if func is None:
> > > ? ? ? ? func = bool
> > > ? ? t, f = [], []
> > > ? ? for item in seq:
> > > ? ? ? ? if func(item):
> > > ? ? ? ? ? ? t.append(item)
> > > ? ? ? ? else:
> > > ? ? ? ? ? ? f.append(item)
> > > ? ? return (t, f)
> >
> > untested:
> >
> > ? ?def split(seq, func=bool):
> > ? ? ? xs = zip(seq, itertools.imap(func, seq))
> > ? ? ? t = list(x for (x,y) in xs if y)
> > ? ? ? f = list(x for (x,y) in xs if not y)
> > ? ? ? return (t, f)
> 
> In my testing that is 3.5x slower than the original solution (and less
> clear imo). I fixed my version to take a bool default. Either way, I'm
> not really looking for additional ways to do this in Python unless
> I've totally missed something. What I am considering is writing it in
> C, much like filter.

I'm a little skeptical that the C version will help much, if it's
evaluating a python function at every list element.  Here's a variant
of your version:

 def split(seq, func=bool):
 ? ? t, f = [], []
     ta, fa = t.append, f.append
 ? ? for item in seq:
         (ta if func(item) else fa)(item)
 ? ? return (t, f)

This avoids some dict lookups and copying.  I wonder if that helps
significantly.


From rylesny at gmail.com  Fri Jul  3 00:13:19 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 2 Jul 2009 21:13:19 -0700 (PDT)
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com> 
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net> 
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<7xfxdev770.fsf@ruckus.brouhaha.com>
	<c74a9109-0d40-46ab-bbf1-79e09e0ddabd@x5g2000yqk.googlegroups.com>
	<7xvdma5ueb.fsf@ruckus.brouhaha.com>
	<mailman.2538.1246592805.8015.python-list@python.org> 
	<7xhbxu4dzz.fsf@ruckus.brouhaha.com>
Message-ID: <34271171-ba63-43bb-b79c-83c036453007@c9g2000yqm.googlegroups.com>

On Jul 2, 11:55?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Yeah, it should allow supplying a predicate instead of using == on
> a value. ?How about (untested):
>
> ? ?from itertools import *
> ? ?...
> ? ?for row in takewhile(lambda x: x is sentinel,
> ? ? ? ? ? ? ? ? ? ? ? ? ?starmap(in_queue.get, repeat(()))):
> ? ? ? ...

Yeah, it's a small recipe I'm sure a lot of others have written as
well. My old version:

def iterwhile(callable_, predicate):
    """ Like iter() but with a predicate instead of a sentinel. """
    return itertools.takewhile(predicate, repeatfunc(callable_))

where repeatfunc is as defined here:

http://docs.python.org/library/itertools.html#recipes

I wish all of these little recipes made their way into itertools or a
like module; itertools seems a bit tightly guarded.


From schickb at gmail.com  Fri Jul  3 00:34:21 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 21:34:21 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
Message-ID: <c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>

On Jul 2, 9:08?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Brad <schi... at gmail.com> writes:
> > On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> > > schickb <schi... at gmail.com> writes:
> > > > def split(seq, func=None):
> > > > ? ? if func is None:
> > > > ? ? ? ? func = bool
> > > > ? ? t, f = [], []
> > > > ? ? for item in seq:
> > > > ? ? ? ? if func(item):
> > > > ? ? ? ? ? ? t.append(item)
> > > > ? ? ? ? else:
> > > > ? ? ? ? ? ? f.append(item)
> > > > ? ? return (t, f)
>
> > > untested:
>
> > > ? ?def split(seq, func=bool):
> > > ? ? ? xs = zip(seq, itertools.imap(func, seq))
> > > ? ? ? t = list(x for (x,y) in xs if y)
> > > ? ? ? f = list(x for (x,y) in xs if not y)
> > > ? ? ? return (t, f)
>
> > In my testing that is 3.5x slower than the original solution (and less
> > clear imo). I fixed my version to take a bool default. Either way, I'm
> > not really looking for additional ways to do this in Python unless
> > I've totally missed something. What I am considering is writing it in
> > C, much like filter.
>
> I'm a little skeptical that the C version will help much, if it's
> evaluating a python function at every list element. ?

Perhaps true, but it would be a nice convenience (for me) as a built-
in written in either Python or C. Although the default case of a bool
function would surely be faster.

> Here's a variant of your version:
>
> ?def split(seq, func=bool):
> ?? ? t, f = [], []
> ? ? ?ta, fa = t.append, f.append
> ?? ? for item in seq:
> ? ? ? ? ?(ta if func(item) else fa)(item)
> ?? ? return (t, f)
>
> This avoids some dict lookups and copying. ?I wonder if that helps
> significantly.

Faster, but in tests of a few short sequences only 1% so.

-Brad


From ldo at geek-central.gen.new_zealand  Fri Jul  3 00:39:46 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Fri, 03 Jul 2009 16:39:46 +1200
Subject: Config files with different types
References: <mailman.2506.1246557392.8015.python-list@python.org>
Message-ID: <h2k22j$i70$1@lust.ihug.co.nz>

In message <mailman.2506.1246557392.8015.python-list at python.org>, Zach 
Hobesh wrote:

> I want to be able to look at the value and determine what type it
> SHOULD be.  Right now, configs['overwrite'] = 'true' (a string) when
> it might be more useful as a boolean.

Typically the type should be what you expect, not what is given. For 
example, it doesn't make sense for your configs["overwrite"] setting to be 
"red", does it?

A reasonable solution might be to have a table of expected types for each 
config item keyword, e.g.

    configs_types = \
        {
           ...
           "overwrite" : lambda x : x[0] not in set("nNfF"),
           ...
        }

Then you can just do something like

    configs[keyword] = configs_types[keyword](configs[keyword])

with appropriate trapping of ValueError exceptions.



From tn.pablo at gmail.com  Fri Jul  3 00:40:13 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 2 Jul 2009 23:40:13 -0500
Subject: Sequence splitting
In-Reply-To: <c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
Message-ID: <fdd00b510907022140g299b4616p64133a2e49716866@mail.gmail.com>

On Thu, Jul 2, 2009 at 23:34, Brad<schickb at gmail.com> wrote:
> On Jul 2, 9:08?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>> Brad <schi... at gmail.com> writes:
>> > On Jul 2, 8:14?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>> > > schickb <schi... at gmail.com> writes:
>> > > > def split(seq, func=None):
>> > > > ? ? if func is None:
>> > > > ? ? ? ? func = bool
>> > > > ? ? t, f = [], []
>> > > > ? ? for item in seq:
>> > > > ? ? ? ? if func(item):
>> > > > ? ? ? ? ? ? t.append(item)
>> > > > ? ? ? ? else:
>> > > > ? ? ? ? ? ? f.append(item)
>> > > > ? ? return (t, f)
>>
>> > > untested:
>>
>> > > ? ?def split(seq, func=bool):
>> > > ? ? ? xs = zip(seq, itertools.imap(func, seq))
>> > > ? ? ? t = list(x for (x,y) in xs if y)
>> > > ? ? ? f = list(x for (x,y) in xs if not y)
>> > > ? ? ? return (t, f)
>>
>> > In my testing that is 3.5x slower than the original solution (and less
>> > clear imo). I fixed my version to take a bool default. Either way, I'm
>> > not really looking for additional ways to do this in Python unless
>> > I've totally missed something. What I am considering is writing it in
>> > C, much like filter.
>>
>> I'm a little skeptical that the C version will help much, if it's
>> evaluating a python function at every list element.
>
> Perhaps true, but it would be a nice convenience (for me) as a built-
> in written in either Python or C. Although the default case of a bool
> function would surely be faster.
>
>> Here's a variant of your version:
>>
>> ?def split(seq, func=bool):
>> ?? ? t, f = [], []
>> ? ? ?ta, fa = t.append, f.append
>> ?? ? for item in seq:
>> ? ? ? ? ?(ta if func(item) else fa)(item)
>> ?? ? return (t, f)
>>
>> This avoids some dict lookups and copying. ?I wonder if that helps
>> significantly.
>
> Faster, but in tests of a few short sequences only 1% so.
>
> -Brad
> --
> http://mail.python.org/mailman/listinfo/python-list
>

If it is speed that we are after, it's my understanding that map and
filter are faster than iterating with the for statement (and also
faster than list comprehensions).  So here is a rewrite:

def split(seq, func=bool):
 	t = filter(func, seq)
 	f = filter(lambda x: not func(x), seq)
 	return list(t), list(f)

The lambda thing is kinda ugly, but I can't think of anything else.
Also, is it ok to return lists?  Py3k saw a lot of APIs changed to
return iterables instead of lists, so maybe my function should have
'return t, f' as it's last statement.


-- 
Pablo Torres N.


From sajmikins at gmail.com  Fri Jul  3 00:40:42 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 2 Jul 2009 21:40:42 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
	<02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>
	<9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
Message-ID: <4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>

On Jul 2, 4:31?am, Tep <petshm... at googlemail.com> wrote:
> On 2 Jul., 10:25, Tep <petshm... at googlemail.com> wrote:
>
>
>
> > On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > someone wrote:
> > > > Hello,
>
> > > > how can I replace '?' sign from string? Or do split at that character?
> > > > Getting unicode error if I try to do it:
>
> > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > > > 1: ordinal not in range(128)
>
> > > > Thanks, Pet
>
> > > > script is # -*- coding: UTF-8 -*-
>
> > > It sounds like you're mixing bytestrings with Unicode strings. I can't
> > > be any more helpful because you haven't shown the code.
>
> > Oh, I'm sorry. Here it is
>
> > def cleanInput(input)
> > ? ? return input.replace('?', '')
>
> I also need:
>
> #input is html source code, I have problem with only this character
> #input = 'foo ? bar'
> #return should be foo
> def splitInput(input)
> ? ? parts = input.split(' ? ')
> ? ? return parts[0]
>
> Thanks!

Okay people want to help you but you must make it easy for us.

Post again with a small piece of code that is runnable as-is and that
causes the traceback you're talking about, AND post the complete
traceback too, as-is.

I just tried a bit of your code above in my interpreter here and it
worked fine:

|>>> data = 'foo ? bar'
|>>> data.split('?')
|['foo ', ' bar']
|>>> data = u'foo ? bar'
|>>> data.split(u'?')
|[u'foo ', u' bar']

Figure out the smallest piece of "html source code" that causes the
problem and include that with your next post.

HTH,
~Simon

You might also read this: http://catb.org/esr/faqs/smart-questions.html


From zookog at gmail.com  Fri Jul  3 00:48:10 2009
From: zookog at gmail.com (zooko)
Date: Thu, 2 Jul 2009 21:48:10 -0700 (PDT)
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org> 
	<h21mgt$oav$1@panix3.panix.com>
	<11eb0a6e-4e21-4a61-bf46-4221fd75dc8d@v15g2000prn.googlegroups.com>
	<006078f0$0$9721$c3e8da3@news.astraweb.com>
	<h22voe$b3k$1@panix3.panix.com> 
	<mailman.2170.1246042676.8015.python-list@python.org>
Message-ID: <f823bca6-e64c-47ea-97e6-a26b50732cb7@x6g2000prc.googlegroups.com>

Try PyJudy:

http://www.dalkescientific.com/Python/PyJudy.html


From http  Fri Jul  3 00:56:40 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 21:56:40 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
Message-ID: <7x3a9egy9j.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> > Yes, but the concept of null pointers is considered kludgy these days.
> Seriously? "kludgy"?  (I really AM getting old.)

  http://math.andrej.com/2009/04/11/on-programming-language-design/

discusses the issue (scroll down to "Undefined values" section).

> Well I wouldn't know, I've been fortunate enough to program mostly in
> python for over half a decade now and None and 0 are as close as I've
> gotten to NULL in a long time.

Right, and how many times have you had to debug

   AttributeError: 'NoneType' object has no attribute 'foo'

or the equivalent null pointer exceptions in Java, C, or whatever?
They are very common.  And the basic idea is that if you avoid using
null pointers in the first place, you'll get fewer accidental null
pointer exceptions.

> That sounds very interesting, but I'm only writing a BTree to then use
> it to play with "persistent data structures" 

But you have implemented a mutable tree.  If you want to write a
persistent one, then write a persistent one!  You also use a wishful
heuristic in the hope of keeping the tree balanced--if you want a
balanced tree, why not use one that's guaranteed to stay in balance?
AVL trees are pretty easy to implement; maybe you could try writing a
persistent one:

  http://en.wikipedia.org/wiki/AVL_tree

> In this particular case it's somewhat more elegant (IMO) to check "is
> None".

Well, I can't understand why that might be, but it's surely
subjective, so ok.

> > I'm sorry but I find that class rather ugly. ?The code would be a lot
> > smaller and have fewer corner cases with a different data representation.
> 
> Um, thanks?  Seriously though, care to put your money where your mouth
> is? I'd be interested to see a BTree implemented as you indicated above.

Er, I'm not trying to argue with you.  You asked for people's advice
and impressions, so I gave you some.  I don't feel like rewriting that
whole class, but I'll do a method or two, using [] to represent an
empty node.  (Hmm, actually changing the empty node representation did
less to shorten the code than just getting rid of a bunch of
duplication.  Really, I'd tend to look for a slightly different tree
structure which tried to avoid these issues).

Untested:

class BinaryTree:
    def __init__(self, key, value):
        self.key = key
        self.value = value
        self.higher = self.lower = []

    def get(self, key):
        if key == self.key:
            return self.value
        branch = self.lower if key < self.key else self.higher
        return branch.get(key) if branch else []

    def insert(self, key, value):
        def xinsert(xtree):  # xtree is either a tree or []
           if not xtree: xtree = BinaryTree(key, value)
           else: xtree.insert(key, value)
           return xtree

        if key == self.key:
            self.value = value
        elif key < self.key:
            self.lower = xinsert(self.lower)
        else:
            self.higher = xinsert(self.higher)

and so forth.


From http  Fri Jul  3 00:58:22 2009
From: http (Paul Rubin)
Date: 02 Jul 2009 21:58:22 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
Message-ID: <7xy6r6fjm9.fsf@ruckus.brouhaha.com>

"Pablo Torres N." <tn.pablo at gmail.com> writes:
> def split(seq, func=bool):
>  	t = filter(func, seq)
>  	f = filter(lambda x: not func(x), seq)
>  	return list(t), list(f)

That is icky--you're calling func (which might be slow) twice instead
of once on every element of the seq.


From lie.1296 at gmail.com  Fri Jul  3 02:05:06 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:05:06 GMT
Subject: question of style
In-Reply-To: <VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
	<VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>
Message-ID: <mch3m.2328$ze1.1288@news-server.bigpond.net.au>

Tim Harig wrote:
>> Speaking only to the style issue, when I've wanted to do something like
>> that, I find:
>>        if self.higher is None is self.lower:
>> more readable, by making clear they are both being compared to a
>> constant, rather than compared to each other.
> 
> By comparing them to *any* constant with 'is' you end up with the same
> potential problems as to whether something with a value of None is actually
> None?  

Oh really? None is a Singleton and all None always point to the same
None object. And the fact that it is impossible to override `is`
operator is the reason for the "is None" idiom.

This does not happen with other objects though (except if you make them
as Singletons as well), and in case of immutable, you may get bugs due
to python's optimizing small integers.

> With equality operators
> everything is either the same or it isn't.   

How about:
class Fake(object):
    def __eq__(self, other):
        return True

we uses `is` when we want to make sure an object is really the same
object as another, not just an equivalent object.

I can start from the first
> variable and compare it to the second then to the third then ...  In the
> case of the inequality, I have to start with the first and compare it to
> all of the rest to make sure that none are the same.  Then I have to do the
> same for each with the remaining.  This is much more difficult to do in my
> head.  I requires much more thought, better left to a computer, when
> evaluating the expression for myself.  Therefore, equalites are quick and
> easy to keep straight whereas any inequalites are more error prone when
> trying to evaluate how a section of code will react under different
> circumstances.
> 
>> I do draw the line at two, though, and with three or more I'll
>> paren-up a list of parallel comparisons:
> 
> As long as everything is an equality, then I don't mind comparing to the
> end of an 70 column line.  Mixed types of equalities or inequalities
> require too many operations mentally evaluate safely.

Personally, I'd only chain inequality for something like this:
if 0 < x < 10:


From lie.1296 at gmail.com  Fri Jul  3 02:09:31 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:09:31 GMT
Subject: question of style
In-Reply-To: <529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
	<529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com>
Message-ID: <vgh3m.2329$ze1.1542@news-server.bigpond.net.au>

Simon Forman wrote:
> On Jul 2, 3:57 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>> Duncan Booth wrote:
>>> Simon Forman <sajmik... at gmail.com> wrote:
>>>> ...
>>>> if self.higher is self.lower is None: return
>>>> ...
>>> As a matter of style however I wouldn't use the shorthand to run two 'is'
>>> comparisons together, I'd write that out in full if it was actually needed
>>> here.
>> Speaking only to the style issue, when I've wanted to do something like
>> that, I find:
>>
>>        if self.higher is None is self.lower:
>>            ...
>>
>> more readable, by making clear they are both being compared to a
>> constant, rather than compared to each other.
> 
> I was going to do it that way for aesthetics if nothing else, but in
> this particular code "self.higher is self.lower" could only have been
> True if they were both None, so the final "is None" was redundant and
> I only included it as a "just-in-case" check in case someone someday
> used the code in such a way as to assign the same object (not None) to
> both self.higher and self.lower...  Totally pointless, I'm sorry to
> say.  I'm glad the whole line was redundant really.
> 

I say, you should keep the `is None` for readability and to safe guard
against immutable optimization and/or Singleton objects. Due to an
implementation detail, python does not guarantee that two immutable
object will return different objects; you have:

>>> a = 1
>>> b = 1
>>> a is b
True


From schickb at gmail.com  Fri Jul  3 02:31:18 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 23:31:18 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
Message-ID: <890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>

On Jul 2, 9:40?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>
> If it is speed that we are after, it's my understanding that map and
> filter are faster than iterating with the for statement (and also
> faster than list comprehensions). ?So here is a rewrite:
>
> def split(seq, func=bool):
> ? ? ? ? t = filter(func, seq)
> ? ? ? ? f = filter(lambda x: not func(x), seq)
> ? ? ? ? return list(t), list(f)
>

In my simple tests, that takes 1.8x as long as the original solution.
Better than the itertools solution, when "func" is short and fast. I
think the solution here would worse if func was more complex.

Either way, what I am still wondering is if people would find a built-
in implementation useful?

-Brad


From gagsl-py2 at yahoo.com.ar  Fri Jul  3 02:31:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 03 Jul 2009 03:31:42 -0300
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<7xy6r6fjm9.fsf@ruckus.brouhaha.com>
Message-ID: <op.uwha24x9x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 01:58:22 -0300, <//phr.cx at nospam.invalid>> escribi?:

> "Pablo Torres N." <tn.pablo at gmail.com> writes:
>> def split(seq, func=bool):
>>  	t = filter(func, seq)
>>  	f = filter(lambda x: not func(x), seq)
>>  	return list(t), list(f)
>
> That is icky--you're calling func (which might be slow) twice instead
> of once on every element of the seq.

In addition, this doesn't work if seq is an iterator instead of a sequence.

-- 
Gabriel Genellina



From lie.1296 at gmail.com  Fri Jul  3 02:33:03 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:33:03 GMT
Subject: question of style
In-Reply-To: <7x63eahp8z.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x63eahp8z.fsf@ruckus.brouhaha.com>
Message-ID: <zCh3m.2331$ze1.2286@news-server.bigpond.net.au>

Paul Rubin wrote:
> Generally, having a special
> value like None to denote a missing datum was considered standard
> practice a few decades ago, 

I guess in python, None as the missing datum idiom is still quite prevalent:

def cat_list(a=None, b=None):
    # poor man's list concatenation
    if a is None and b is None: return []
    if a is None: return b
    if b is None: return a
    return a + b


From schickb at gmail.com  Fri Jul  3 02:34:21 2009
From: schickb at gmail.com (Brad)
Date: Thu, 2 Jul 2009 23:34:21 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
Message-ID: <e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>

On Jul 2, 8:17?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>
> This sounds like it belongs to the python-ideas list. ?I suggest
> posting there for better feedback, since the core developers check
> that list more often than this one.

I tried posting on python-ideas and received a "You are not allowed to
post to this mailing list" reply. Perhaps because I am posting through
Google groups? Or maybe one must be an approved member to post?

-Brad


From lie.1296 at gmail.com  Fri Jul  3 02:37:32 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:37:32 GMT
Subject: question of style
In-Reply-To: <mch3m.2328$ze1.1288@news-server.bigpond.net.au>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net>
	<VK83m.1773$cl4.136@flpi150.ffdc.sbc.com>
	<mch3m.2328$ze1.1288@news-server.bigpond.net.au>
Message-ID: <MGh3m.2332$ze1.684@news-server.bigpond.net.au>

Lie Ryan wrote:
> Tim Harig wrote:
>>> Speaking only to the style issue, when I've wanted to do something like
>>> that, I find:
>>>        if self.higher is None is self.lower:
>>> more readable, by making clear they are both being compared to a
>>> constant, rather than compared to each other.
>> By comparing them to *any* constant with 'is' you end up with the same
>> potential problems as to whether something with a value of None is actually
>> None?  
> 
> Oh really? None is a Singleton and all None always point to the same
> None object. And the fact that it is impossible to override `is`
> operator is the reason for the "is None" idiom.
> 

http://docs.python.org/c-api/none.html


From aotto1968 at users.sourceforge.net  Fri Jul  3 02:39:17 2009
From: aotto1968 at users.sourceforge.net (Andreas Otto)
Date: Fri, 03 Jul 2009 08:39:17 +0200
Subject: ANNOUNCE: libmsgque 3.4
Message-ID: <h2k93v$m68$02$1@news.t-online.com>


Dear Users,

  I would like to provide a new !! Major Feature Release !! of 	

	>>> LibMsgque (3.4) <<<

  This Release Introduce a new technology called

	>>> Master / Slave - Link <<<

  and is used to create, mange and configure a MESH of
  node's (process or thread) distributed over multiple hosts.

  But a picture says more then all the words, read more at:

      -> http://libmsgque.sourceforge.net/master_versa_slave.htm

  To get the Details and the Downloads read more at:

      -> http://libmsgque.sourceforge.net/  

  P.S. sourceforge introduce a new interface yesterday ....
         and this has still some bugs ...
         to get the release 3.4 files you have to use the files link.


mfg

  Andreas Otto





From lie.1296 at gmail.com  Fri Jul  3 02:40:19 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:40:19 GMT
Subject: question of style
In-Reply-To: <7xljn6pvgk.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<7xljn6pvgk.fsf@ruckus.brouhaha.com>
Message-ID: <nJh3m.2333$ze1.1924@news-server.bigpond.net.au>

Paul Rubin wrote:
> Tim Harig <usernet at ilthio.net> writes:
>> That being the case, it might be a good idea either to handle the situation
>> and raise an exception or add:
>>
>> assert self.lower <= self.higher
>>
>> That way an exception will be raised if there is an error somewhere else
>> in the code rather then silently passing a possibly incorrect value.
> 
> Well, that assert is not right because you have to handle the case
> where one of the values is None.  The general sentiment is reasonable
> though, if you're concerned that the precondition may not be valid.

Well, it depends on where you put the assert statement. If your code is
like this:

if self.higher is self.lower is None: return
if self.lower is None: return self.higher
if self.higher is None: return self.lower
assert self.lower <= self.higher

then the assert statement is correct.

Some people might prefer to keep all asserts at the top of function though.


From ricli85 at gmail.com  Fri Jul  3 02:46:46 2009
From: ricli85 at gmail.com (Rickard Lindberg)
Date: Fri, 3 Jul 2009 08:46:46 +0200
Subject: Sequence splitting
In-Reply-To: <e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
	<e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
Message-ID: <890d8ab70907022346r635b00dfr5001e65838a1b994@mail.gmail.com>

> I tried posting on python-ideas and received a "You are not allowed to
> post to this mailing list" reply. Perhaps because I am posting through
> Google groups? Or maybe one must be an approved member to post?

If you got an "awaiting moderator approval" message you post might appear on
the list soon. The reason for getting those can be that it is a member only
list and you posted from another address. I am not sure if that was the message
you got.

-- 
Rickard Lindberg


From lie.1296 at gmail.com  Fri Jul  3 02:47:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 06:47:49 GMT
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <pQh3m.2334$ze1.180@news-server.bigpond.net.au>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?

If self is an object (and it must have been), it would be preferrable to
set self.higher and self.lower to a known value inside self.__init__ and
avoid having the comparison.

I'm guessing you have something like this in your __init__:

def __init__(self, lower=None, higher=None):
    self.lower = lower
    self.higher = higher


that should be changed to:

def __init__(self, lower=None, higher=None):
    self.lower = lower if lower is not None else higher
    self.higher = higher if lower is not None else lower

or whatever else-value you see is appropriate for the context.


From javier.collado at gmail.com  Fri Jul  3 02:55:28 2009
From: javier.collado at gmail.com (Javier Collado)
Date: Fri, 3 Jul 2009 08:55:28 +0200
Subject: Config files with different types
In-Reply-To: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
References: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com>
Message-ID: <c83cde5a0907022355y706ea932w78649a17ed756809@mail.gmail.com>

Hello,

Have you considered using something that is already developed?

You could take a look at this presentation for an overview of what's available:
http://us.pycon.org/2009/conference/schedule/event/5/

Anyway, let me explain that, since I "discovered" it, my favourite
format for configuration files is yaml (http://yaml.org/,
http://pyyaml.org/). It's easy to read, easy to write, available in
different programming languagues, etc. In addition to this, type
conversion is already in place so I think it covers your requirement.
For example:

IIn [1]: import yaml

In [2]: yaml.load("""name: person name
   ...: age: 25
   ...: is_programmer: true""")
Out[2]: {'age': 25, 'is_programmer': True, 'name': 'person name'}

Best regards,
    Javier

2009/7/2 Zach Hobesh <hobesh at gmail.com>:
> Hi all,
>
> I've written a function that reads a specifically formatted text file
> and spits out a dictionary. ?Here's an example:
>
> config.txt:
>
> Destination = C:/Destination
> Overwrite = True
>
>
> Here's my function that takes 1 argument (text file)
>
> the_file = open(textfile,'r')
> linelist = the_file.read().split('\n')
> the_file.close()
> configs = {}
> for line in linelist:
> ? ? ? try:
> ? ? ? ? ? ? ?key,value = line.split('=')
> ? ? ? ? ? ? ?key.strip()
> ? ? ? ? ? ? ?value.strip()
> ? ? ? ? ? ? ?key.lower()
> ? ? ? ? ? ? ?value.lower()
> ? ? ? ? ? ? ?configs[key] = value
>
> ? ? ? except ValueError:
> ? ? ? ? ? ? ?break
>
> so I call this on my config file, and then I can refer back to any
> config in my script like this:
>
> shutil.move(your_file,configs['destination'])
>
> which I like because it's very clear and readable.
>
> So this works great for simple text config files. ?Here's how I want
> to improve it:
>
> I want to be able to look at the value and determine what type it
> SHOULD be. ?Right now, configs['overwrite'] = 'true' (a string) when
> it might be more useful as a boolean. ?Is there a quick way to do
> this? ?I'd also like to able to read '1' as an in, '1.0' as a float,
> etc...
>
> I remember once I saw a script that took a string and tried int(),
> float() wrapped in a try except, but I was wondering if there was a
> more direct way.
>
> Thanks in advance,
>
> Zach
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From hv at tbz-pariv.de  Fri Jul  3 03:02:06 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Fri, 03 Jul 2009 09:02:06 +0200
Subject: logging of strings with broken encoding
In-Reply-To: <4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
	<4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>
Message-ID: <7b5oneF223712U1@mid.individual.net>

Stefan Behnel schrieb:
> Thomas Guettler wrote:
>> My quick fix is this:
>>
>> class MyFormatter(logging.Formatter):
>>     def format(self, record):
>>         msg=logging.Formatter.format(self, record)
>>         if isinstance(msg, str):
>>             msg=msg.decode('utf8', 'replace')
>>         return msg
>>
>> But I still think handling of non-ascii byte strings should be better.
>> A broken logging message is better than none.
> 
> Erm, may I note that this is not a problem in the logging library but in
> the code that uses it?

I know that my code passes the broken string to the logging module. But maybe
I get the non-ascii byte string from a third party (psycopg2 sometime passes
latin1 byte strings from postgres in error messages).

I like Python very much because "it refused to guess". But in this case, "best effort"
is a better approach.

It worked in 2.5 and will in py3k. I think it is a bug, that it does not in 2.6.

 Thomas



-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From lie.1296 at gmail.com  Fri Jul  3 03:16:35 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 07:16:35 GMT
Subject: Sequence splitting
In-Reply-To: <890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
Message-ID: <nfi3m.2341$ze1.1151@news-server.bigpond.net.au>

Brad wrote:
> On Jul 2, 9:40 pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>> If it is speed that we are after, it's my understanding that map and
>> filter are faster than iterating with the for statement (and also
>> faster than list comprehensions).  So here is a rewrite:
>>
>> def split(seq, func=bool):
>>         t = filter(func, seq)
>>         f = filter(lambda x: not func(x), seq)
>>         return list(t), list(f)
>>
> 
> In my simple tests, that takes 1.8x as long as the original solution.
> Better than the itertools solution, when "func" is short and fast. I
> think the solution here would worse if func was more complex.
> 
> Either way, what I am still wondering is if people would find a built-
> in implementation useful?
> 
> -Brad

A built-in/itertools should always try to provide the general solution
to be as useful as possible, something like this:

def group(seq, func=bool):
    ret = {}
    for item in seq:
        fitem = func(item)
        try:
            ret[fitem].append(item)
        except KeyError:
            ret[fitem] = [item]
    return ret

definitely won't be faster, but it is a much more general solution.
Basically, the function allows you to group sequences based on the
result of func(item). It is similar to itertools.groupby() except that
this also group non-contiguous items.


From lie.1296 at gmail.com  Fri Jul  3 03:25:28 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 07:25:28 GMT
Subject: logging of strings with broken encoding
In-Reply-To: <7b5oneF223712U1@mid.individual.net>
References: <7b3vpqF20nct6U1@mid.individual.net>
	<7b43faF21l89hU1@mid.individual.net>
	<4a4ce7f1$0$32669$9b4e6d93@newsspool2.arcor-online.net>
	<7b5oneF223712U1@mid.individual.net>
Message-ID: <Ini3m.2342$ze1.1804@news-server.bigpond.net.au>

Thomas Guettler wrote:
> Stefan Behnel schrieb:
>> Thomas Guettler wrote:
>>> My quick fix is this:
>>>
>>> class MyFormatter(logging.Formatter):
>>>     def format(self, record):
>>>         msg=logging.Formatter.format(self, record)
>>>         if isinstance(msg, str):
>>>             msg=msg.decode('utf8', 'replace')
>>>         return msg
>>>
>>> But I still think handling of non-ascii byte strings should be better.
>>> A broken logging message is better than none.
>> Erm, may I note that this is not a problem in the logging library but in
>> the code that uses it?
> 
> I know that my code passes the broken string to the logging module. But maybe
> I get the non-ascii byte string from a third party (psycopg2 sometime passes
> latin1 byte strings from postgres in error messages).

If the database contains non-ascii byte string, then you could repr()
them before logging (repr also adds some niceties such as quotes). I
think that's the best solution, unless you want to decode the byte
string (which might be an overkill, depending on the situation).

> I like Python very much because "it refused to guess". But in this case, "best effort"
> is a better approach.

One time it refused to guess, then the next time it tries best effort. I
don't think Guido liked such inconsistency.

> It worked in 2.5 and will in py3k. I think it is a bug, that it does not in 2.6.

In python 3.x, the default string is unicode string. If it works in
python 2.5, then it is a bug in 2.5


From http  Fri Jul  3 03:27:54 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 00:27:54 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x63eahp8z.fsf@ruckus.brouhaha.com>
	<zCh3m.2331$ze1.2286@news-server.bigpond.net.au>
Message-ID: <7x8wj6usxx.fsf@ruckus.brouhaha.com>

Lie Ryan <lie.1296 at gmail.com> writes:
> I guess in python, None as the missing datum idiom is still quite prevalent:

Well, sometimes there is no way around it, but:

> def cat_list(a=None, b=None):
>     # poor man's list concatenation
>     if a is None and b is None: return []
>     if a is None: return b
>     if b is None: return a
>     return a + b

def cat_list(a=[], b=[]):
    return a + b


From nillgump at gmail.com  Fri Jul  3 03:31:27 2009
From: nillgump at gmail.com (nillgump)
Date: Fri, 3 Jul 2009 00:31:27 -0700 (PDT)
Subject: use python to edit pdf document
Message-ID: <7094d63e-21a6-4b1a-995a-280b0b1b26c4@q40g2000prh.googlegroups.com>

hi all.
I  are looking for some packages which use python to edit pdf format
docutment.
when I searched the internet,I found  the
paper  " Using Python as PDF Editing and Processing Framework"  which
is at:
*********http://www.python.org/workshops/2002-02/papers/17/
index.htm*********
this paper is posted at  2002.it  had a  long  years.But I cann't
find  the impletation.
Does anyone know what  happened  about
this?And  I  have seen the Reportlab  which can generate the pdf .But
what I  want is not only this,but also can edit the pdf.
So does  everyone know there  are some
exsiting python packages about this?
With using the exsiting  things,I can save
much work.
Any advice is  appropriated!

--nillgump
--2009/7/3
--China


From lie.1296 at gmail.com  Fri Jul  3 03:31:45 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 07:31:45 GMT
Subject: Sequence splitting
In-Reply-To: <mailman.2541.1246603608.8015.python-list@python.org>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>	<e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
	<mailman.2541.1246603608.8015.python-list@python.org>
Message-ID: <Bti3m.2343$ze1.992@news-server.bigpond.net.au>

Rickard Lindberg wrote:
>> I tried posting on python-ideas and received a "You are not allowed to
>> post to this mailing list" reply. Perhaps because I am posting through
>> Google groups? Or maybe one must be an approved member to post?
> 
> If you got an "awaiting moderator approval" message you post might appear on
> the list soon. The reason for getting those can be that it is a member only
> list and you posted from another address. I am not sure if that was the message
> you got.
> 

AFAIK, python-ideas is not moderated (I followed python-ideas). I've
never used Google Groups to access it though. Try subscribing to the
mailing list directly (instead of using Google Group's web-gateway)
here: http://mail.python.org/mailman/listinfo/python-ideas


From clp2 at rebertia.com  Fri Jul  3 03:44:43 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 00:44:43 -0700
Subject: use python to edit pdf document
In-Reply-To: <7094d63e-21a6-4b1a-995a-280b0b1b26c4@q40g2000prh.googlegroups.com>
References: <7094d63e-21a6-4b1a-995a-280b0b1b26c4@q40g2000prh.googlegroups.com>
Message-ID: <50697b2c0907030044p740e0e96h3f1ac9a81b578d57@mail.gmail.com>

On Fri, Jul 3, 2009 at 12:31 AM, nillgump<nillgump at gmail.com> wrote:
> hi all.
> I ?are looking for some packages which use python to edit pdf format
> docutment.
> when I searched the internet,I found ?the
> paper ?" Using Python as PDF Editing and Processing Framework" ?which
> is at:
> *********http://www.python.org/workshops/2002-02/papers/17/
> index.htm*********
> this paper is posted at ?2002.it ?had a ?long ?years.But I cann't
> find ?the impletation.
> Does anyone know what ?happened ?about
> this?And ?I ?have seen the Reportlab ?which can generate the pdf .But
> what I ?want is not only this,but also can edit the pdf.

See ReportLab's proprietary+commercial PageCatcher library
(http://developer.reportlab.com/).

Cheers,
Chris
-- 
http://blog.rebertia.com


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 03:50:53 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 07:50:53 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
Message-ID: <025da9f8$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 21:56:40 -0700, Paul Rubin wrote:

>> Well I wouldn't know, I've been fortunate enough to program mostly in
>> python for over half a decade now and None and 0 are as close as I've
>> gotten to NULL in a long time.
> 
> Right, and how many times have you had to debug
> 
>    AttributeError: 'NoneType' object has no attribute 'foo'

Hardly ever, and mostly when I do something silly like:

another_list = alist.sort()

Of course, YMMV.



> or the equivalent null pointer exceptions in Java, C, or whatever? They
> are very common.  And the basic idea is that if you avoid using null
> pointers in the first place, you'll get fewer accidental null pointer
> exceptions.

And some other error instead, due to the bugs in your more complicated 
code *wink*



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 03:57:02 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 07:57:02 GMT
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
Message-ID: <025dab69$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 22:10:14 -0500, Pablo Torres N. wrote:

> This sounds like it belongs to the python-ideas list.  I suggest posting
> there for better feedback, since the core developers check that list
> more often than this one.

If you post to python-ideas, you'll probably be told to gather feedback 
here first. The core-developers aren't hugely interested in arbitrary new 
features unless they have significant community support.

I've never needed such a split function, and I don't like the name, and 
the functionality isn't general enough. I'd prefer something which splits 
the input sequence into as many sublists as necessary, according to the 
output of the key function. Something like itertools.groupby(), except it 
runs through the entire sequence and collates all the elements with 
identical keys.

E.g.:

splitby(range(10), lambda n: n%3)
=> [ (0, [0, 3, 6, 9]),
     (1, [1, 4, 7]), 
     (2, [2, 5, 8]) ]

Your split() would be nearly equivalent to this with a key function that 
returns a Boolean.



-- 
Steven




From http  Fri Jul  3 04:02:56 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 01:02:56 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7x1voy5h3j.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> I've never needed such a split function, and I don't like the name, and 
> the functionality isn't general enough. I'd prefer something which splits 
> the input sequence into as many sublists as necessary, according to the 
> output of the key function. Something like itertools.groupby(), except it 
> runs through the entire sequence and collates all the elements with 
> identical keys.

No really, groupby makes iterators, not lists, and it you have to
develop quite a delicate sense of when you can use it without having
bugs caused by the different iterators it makes getting advanced at
the wrong times.  The concept of a split function that actually works
on lists is useful.  I'm neutral about whether it's worth having a C
version in the stdlib.


From lie.1296 at gmail.com  Fri Jul  3 04:06:18 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 08:06:18 GMT
Subject: question of style
In-Reply-To: <7x8wj6usxx.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x63eahp8z.fsf@ruckus.brouhaha.com>
	<zCh3m.2331$ze1.2286@news-server.bigpond.net.au>
	<7x8wj6usxx.fsf@ruckus.brouhaha.com>
Message-ID: <_Zi3m.2347$ze1.458@news-server.bigpond.net.au>

Paul Rubin wrote:
> Lie Ryan <lie.1296 at gmail.com> writes:
>> I guess in python, None as the missing datum idiom is still quite prevalent:
> 
> Well, sometimes there is no way around it, but:
> 
>> def cat_list(a=None, b=None):
>>     # poor man's list concatenation
>>     if a is None and b is None: return []
>>     if a is None: return b
>>     if b is None: return a
>>     return a + b
> 
> def cat_list(a=[], b=[]):
>     return a + b

Being super contrived is why I tagged it as poor man's concat.
Generally, there will be a processing:

...
    if b is None: return a
    # processing here
    return retlist
...

and it will not be about concatenating two lists, but something more
complex. But I thought that was unnecessary since I just want to mention
about the None argument idiom.


From stef.mientki at gmail.com  Fri Jul  3 04:07:50 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Fri, 03 Jul 2009 10:07:50 +0200
Subject: Adding an object to the global namespace through " f_globals"
	is that allowed ?
In-Reply-To: <4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>
References: <4A4BC22D.70502@gmail.com>	<mailman.2467.1246512323.8015.python-list@python.org>
	<4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>
Message-ID: <4A4DBC56.9020202@gmail.com>

ryles wrote:
> On Jul 2, 1:25 am, Terry Reedy <tjre... at udel.edu> wrote:
>   
>>> The next statement works,
>>> but I'm not sure if it will have any dramatical side effects,
>>> other than overruling a possible object with the name A
>>>       
>>> def some_function ( ...) :
>>>      A = object ( ...)
>>>      sys._getframe(1).f_globals [ Name ] = A
>>>       
>> global name
>> name = A
>>
>> or is name is a string var
>> globals()[name] = A
>>     
>
> It wasn't explicit, but I think Stef meant that the global should be
> added to the caller's environment, which was the reason for
> sys._getframe().
>
> Is this environment only intended for interactive use? I wonder if you
> might just set things up
> in a PYTHONSTARTUP script instead.
>   
the idea is to get a simple environment where you can do interactive 3D 
geometry,
without knowing anything about Python.
So to create a triangle e.g., the whole program will look like this:

Point ( 'A', (1,1,0) )
Point ( 'B', (5,5,0) )
Point ( 'C', (1,5,0) )
Line_Segment ( 'AB' )
Line_Segment ( 'BC' ) 
Line_Segment ( 'AC' )

   

And now the points A,B,C and the line segments AB,BC,AC also exists as 
variables in the namespace of the above environment.
So now you can add a point "D" in the middle of the line-segment AB, by 
giving the formula of that point:

Point ( 'D',  ' ( A + B ) / 2 ' )

Or display the properties of point A, with :

Print A

which (for the moment) will result in:

Point Instance: A
  Childs : AB(Line-Segment), AC(Line-Segment),
  Parents:

The graphics above is done in VPython, which gives you an easy way to 
make all objects dragable,
and if objects are defined by formulas, the will stick together 
according to that formula.

And now it's obvious I can't use the solution of Terry,
because I don't know what names will to become global.

thanks,
Stef


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/f1a53503/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: moz-screenshot-3.jpg
Type: image/jpeg
Size: 3333 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/f1a53503/attachment-0001.jpg>

From ldo at geek-central.gen.new_zealand  Fri Jul  3 04:08:20 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Fri, 03 Jul 2009 20:08:20 +1200
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
	<mailman.2446.1246491262.8015.python-list@python.org>
Message-ID: <h2ke9k$os8$3@lust.ihug.co.nz>

In message <mailman.2446.1246491262.8015.python-list at python.org>, Jo?o 
Valverde wrote:

> Lawrence D'Oliveiro wrote:
>
>> In message <mailman.2140.1245996088.8015.python-list at python.org>, Jo?o
>> Valverde wrote:
>>   
>>> Simple example usage case: Insert string into data structure in sorted
>>> order if it doesn't exist, else retrieve it.
>>
>>     the_set = set( ... )
>>
>>     if str in the_set :
>>         ... "retrieval" case ...
>>     else :
>>         the_set.add(str)
>>     #end if
>>
>> Want sorted order?
>>
>>     sorted(tuple(the_set))
>>
>> What could be simpler?
> 
> Try putting that inside a loop with thousands of iterations and you'll
> see what the problem is.

You could apply the same argument to anything. E.g. why create a tree 
structure with a million elements? Try putting that inside a loop with 
thousands of iterations and you'll see what the problem is.



From deets at nospam.web.de  Fri Jul  3 04:11:02 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 03 Jul 2009 10:11:02 +0200
Subject: XML(JSON?)-over-HTTP:  How to define API?
In-Reply-To: <mailman.2520.1246573083.8015.python-list@python.org>
References: <mailman.2520.1246573083.8015.python-list@python.org>
Message-ID: <7b5somF21peceU1@mid.uni-berlin.de>

Allen Fowler schrieb:
> 
> 
> 
>> I have an (in-development) python system that needs to shuttle events / requests 
>> around over the network to other parts of itself.   It will also need to 
>> cooperate with a .net application running on yet a different machine.
>>
>> So, naturally I figured some sort of HTTP event / RPC type of would be a good 
>> idea?
>>
>> Are there any modules I should know about, or guidelines I could read, that 
>> could aid me in the design of the API?    
>>
>>
> 
> 
> To clarify:
> 
> Each message would be <1KB of data total, and consist of some structured object containing strings, numbers, dates, etc.
> 
> For instance there would be an "add user" request that would contain one or more User objects each having a number of properties like:
> 
> - Full Name
> - Username
> - Password
> - Email addresses (a variable length array)
> - Street Address line1
> - Street Address line1
> - Street Address line1
> - City
> - State
> - Zip
> - Sign Up Date
> 
> .... and so on.
> 
> 
> Since I need to work with other platforms, pickle is out...  what are the alternatives?  XML? JSON?
> 
> How should I formally define each of the valid messages and objects?
> 
> Thank you,

Use XMLRPC. Implementations for both languages are available. There is 
no need for formal spec - which is a good thing. You just call the 
server, and it works.

Diez


From clp2 at rebertia.com  Fri Jul  3 04:12:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 01:12:20 -0700
Subject: Sequence splitting
In-Reply-To: <890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
Message-ID: <50697b2c0907030112g38a3c992tb07eea45acc58312@mail.gmail.com>

On Thu, Jul 2, 2009 at 11:31 PM, Brad<schickb at gmail.com> wrote:
> On Jul 2, 9:40?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>>
>> If it is speed that we are after, it's my understanding that map and
>> filter are faster than iterating with the for statement (and also
>> faster than list comprehensions). ?So here is a rewrite:
>>
>> def split(seq, func=bool):
>> ? ? ? ? t = filter(func, seq)
>> ? ? ? ? f = filter(lambda x: not func(x), seq)
>> ? ? ? ? return list(t), list(f)
>>
>
> In my simple tests, that takes 1.8x as long as the original solution.
> Better than the itertools solution, when "func" is short and fast. I
> think the solution here would worse if func was more complex.
>
> Either way, what I am still wondering is if people would find a built-
> in implementation useful?

FWIW, Ruby has Enumerable#partition, which does the same thing as
split() and has a better name IMHO.
http://www.ruby-doc.org/core/classes/Enumerable.html#M003130

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Fri Jul  3 04:15:35 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 01:15:35 -0700
Subject: Adding an object to the global namespace through " f_globals" is 
	that allowed ?
In-Reply-To: <4A4DBC56.9020202@gmail.com>
References: <4A4BC22D.70502@gmail.com>
	<mailman.2467.1246512323.8015.python-list@python.org>
	<4eab6e76-833a-4cc7-a21d-c3d8ed344f8e@a7g2000yqk.googlegroups.com>
	<4A4DBC56.9020202@gmail.com>
Message-ID: <50697b2c0907030115l5aab4816i159eb22d39785f0f@mail.gmail.com>

On Fri, Jul 3, 2009 at 1:07 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
> ryles wrote:
>
> On Jul 2, 1:25 am, Terry Reedy <tjre... at udel.edu> wrote:
>
>
> The next statement works,
> but I'm not sure if it will have any dramatical side effects,
> other than overruling a possible object with the name A
>
>
> def some_function ( ...) :
>      A = object ( ...)
>      sys._getframe(1).f_globals [ Name ] = A
>
>
> global name
> name = A
>
> or is name is a string var
> globals()[name] = A
>
>
> It wasn't explicit, but I think Stef meant that the global should be
> added to the caller's environment, which was the reason for
> sys._getframe().
>
> Is this environment only intended for interactive use? I wonder if you
> might just set things up
> in a PYTHONSTARTUP script instead.
>
>
> the idea is to get a simple environment where you can do interactive 3D
> geometry,
> without knowing anything about Python.
> So to create a triangle e.g., the whole program will look like this:
>
> Point ( 'A', (1,1,0) )
> Point ( 'B', (5,5,0) )
> Point ( 'C', (1,5,0) )
> Line_Segment ( 'AB' )
> Line_Segment ( 'BC' )
> Line_Segment ( 'AC' )
>
>
>
> And now the points A,B,C and the line segments AB,BC,AC also exists as
> variables in the namespace of the above environment.
> So now you can add a point "D" in the middle of the line-segment AB, by
> giving the formula of that point:
>
> Point ( 'D',? ' ( A + B ) / 2 ' )
>
> Or display the properties of point A, with :
>
> Print A
>
> which (for the moment) will result in:
>
> Point Instance: A
> ? Childs : AB(Line-Segment), AC(Line-Segment),
> ? Parents:
>
> The graphics above is done in VPython, which gives you an easy way to make
> all objects dragable,
> and if objects are defined by formulas, the will stick together according to
> that formula.
>
> And now it's obvious I can't use the solution of Terry,
> because I don't know what names will to become global.

Have you considered just using imports instead? Requiring a single opaque:

from graphicslibthingy import *

at the start of a file using the environment isn't so bad, IMHO.

Cheers,
Chris
-- 
http://blog.rebertia.com


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:18:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:18:19 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
Message-ID: <025db066$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 22:14:18 +0000, Tim Harig wrote:

> On 2009-07-02, Paul Rubin <http> wrote:
>> Tim Harig <usernet at ilthio.net> writes:
>>> If lower is 5 and higher is 3, then it returns 3 because 3 != None in
>>> the first if.
>> Sorry, the presumption was that lower <= higher, i.e. the comparison
>> had already been made and the invariant was enforced by the class
>> constructor.  The comment should have been more explicit, I guess.
> 
> That being the case, it might be a good idea either to handle the
> situation and raise an exception or add:
> 
> assert self.lower <= self.higher

Only if you want strange and mysterious bugs whenever somebody runs your 
code with the -O flag.

 
> That way an exception will be raised if there is an error somewhere else
> in the code rather then silently passing a possibly incorrect value.

asserts are disabled when the -O flag is given.

You should never use asserts for testing data. That's not what they're 
for. They're for testing program logic (and unit-testing).

This is wrong, because it will sometimes fail when running under -O:

def parrot(colour):
    assert colour.lower() in ('red', 'green', 'blue')
    return "Norwegian %s" % colour.title()

That should be written as test followed by an explicit raise:

def parrot(colour):
    if colour.lower() not in ('red', 'green', 'blue'):
        raise ValueError
    return "Norwegian %s" % colour.title()


An acceptable use for assert is to verify your program logic by testing 
something which should never fail. If it does fail, then you know 
something bizarre and unexpected has happened, and you have a program bug 
rather than bad data. Here's a silly example:


def cheese_available(kind):
    """Return True if the kind of cheese specified is in stock
    in the cheeseshop run by Michael Palin.

    This function always returns False.
    """
    return False


def get_cheese():
    exchange_amusing_banter()
    for kind in ('Cheddar', 'Gouda', 'Swiss', 'Camembert'):
        ask_proprietor("Do you have any %s?" % kind)
        flag = cheese_available(kind)
        assert not flag
        if flag:
            buy_cheese(kind)
            return None
        else:
            express_disappointment()
    # We only get here if no cheese is bought.
    print "Cleese: Does this cheeseshop actually have ANY cheese?"
    print "Palin: No sir, I'm afraid I've been wasting your time."
    print "Cleese: Well then, I'm going to have to shoot you."



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:19:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:19:23 GMT
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
Message-ID: <025db0a6$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:

> I'm sure that it is possible to find cases in which the *current*
> implementation of re.search() would be inefficient, but that's because
> this implementation is perverse, which, I guess, is ultimately the point
> of my original post.  Why privilege the special case of a
> start-of-string anchor?  

Because wanting to see if a string matches from the beginning is a very 
important and common special case.


> What if you wanted to apply an end-anchored
> pattern to some prefix of your 4GB string?  Why not have a special re
> method for that?  And another for every possible special case?

Because they're not common special cases. They're rare and not special 
enough to justify special code.


> If the concern is efficiency for such cases, then simply implement
> optional offset and length parameters for re.search(), to specify any
> arbitrary substring to apply the search to.  To have a special-case
> re.match() method in addition to a general re.search() method is
> antithetical to language minimalism, and plain-old bizarre.  Maybe
> there's a really good reason for it, but it has not been mentioned yet.

There is, and it has. You're welcome to keep your own opinion, but I 
don't think you'll find many experienced Python coders will agree with it.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:21:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:21:09 GMT
Subject: PEP368 and pixeliterators
References: <mailman.2475.1246523526.8015.python-list@python.org>
Message-ID: <025db110$0$20657$c3e8da3@news.astraweb.com>

On Thu, 02 Jul 2009 10:32:04 +0200, Joachim Str?mbergson wrote:

> for pixel in rgb_image:
>     # swap red and blue, and set green to 0 pixel.value = pixel.b, 0,
>     pixel.r
> 
> 
> The idea I'm having is that fundamentally the image is made up of a 2D
> array of pixels, not rows of pixels.

A 2D array implies rows (and columns) of pixels.




-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:26:59 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:26:59 GMT
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
Message-ID: <025db26e$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 01:02:56 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> I've never needed such a split function, and I don't like the name, and
>> the functionality isn't general enough. I'd prefer something which
>> splits the input sequence into as many sublists as necessary, according
>> to the output of the key function. Something like itertools.groupby(),
>> except it runs through the entire sequence and collates all the
>> elements with identical keys.
> 
> No really, groupby makes iterators, not lists, and it you have to
> develop quite a delicate sense of when you can use it without having
> bugs caused by the different iterators it makes getting advanced at the
> wrong times.  The concept of a split function that actually works on
> lists is useful.  I'm neutral about whether it's worth having a C
> version in the stdlib.

groupby() works on lists.

The difference between what I'm suggesting and what groupby() does is 
that my suggestion would collate *all* the elements with the same key, 
not just runs of them. This (as far as I can tell) requires returning 
lists rather than iterators.

The most important difference between my suggestion and that of the OP is 
that he limited the key function to something which returns a truth 
value, while I'm looking for something more general which can split the 
input into an arbitrary number of collated sublists.



-- 
Steven


From nick at craig-wood.com  Fri Jul  3 04:30:02 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Fri, 03 Jul 2009 03:30:02 -0500
Subject: how to spawn a process under different user
References: <b7e0d3b0-b36d-4da7-b728-445c887738d3@v37g2000prg.googlegroups.com>
	<mailman.2516.1246568293.8015.python-list@python.org>
	<25765da2-7d27-48c8-b7c8-125fdc6c1c71@g1g2000pra.googlegroups.com>
	<Zua3m.3615$Jb1.1092@flpi144.ffdc.sbc.com>
	<mailman.2529.1246584451.8015.python-list@python.org>
Message-ID: <slrnh4refh.vpl.nick@irishsea.home.craig-wood.com>

Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>  En Thu, 02 Jul 2009 19:27:05 -0300, Tim Harig <usernet at ilthio.net>
>  escribi?:
> > On 2009-07-02, sanket <sanket.s.patel at gmail.com> wrote:
> >>> sanket wrote:
> >>> > I am trying to use python's subprocess module to launch a process.
> >>> > but in order to do that I have to change the user.
> >> I am using python 2.4 on centos.
> >
> > I have never done this in python; but, using the normal system calls in C
> > the process is basically:
> > 	
> > 	1. fork() a  new process
> > 	2. the child process changes its user id with setreuid() and
> > 		possibly its group id with setregid()
> > 	3. then the child exec()s new process which replaces itself
> >
> > All of the necessary functions should be under the os module on POSIX
> > operating systems.
> 
>  How to do that using the subprocess module: write a function for item (2)
>  above and pass it as the preexec_fn argument to Popen. preexec_fn is
>  executed after fork() and before exec()

If you are forking 100s of processes a second you want to use the
method above, however I think it is easier to use su (assuming you
start off as root),

so instead of passing

  ['mycommand', 'my_arg1', 'my_arg2']

to Popen, pass

  ['su', '-', 'username', '-c', 'mycommand my_arg1 my_arg2']

There is some opportunity for quoting problems there, but it is easy!

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From http  Fri Jul  3 04:33:27 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 01:33:27 -0700
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
	<mailman.2446.1246491262.8015.python-list@python.org>
	<h2ke9k$os8$3@lust.ihug.co.nz>
Message-ID: <7xocs2go88.fsf@ruckus.brouhaha.com>

Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> writes:
> >> Want sorted order?
> >>     sorted(tuple(the_set))
> >> What could be simpler?
> > 
> > Try putting that inside a loop with thousands of iterations and you'll
> > see what the problem is.
> 
> You could apply the same argument to anything. E.g. why create a tree 
> structure with a million elements? Try putting that inside a loop with 
> thousands of iterations and you'll see what the problem is.

The idea is you're going to insert or delete something in the tree
structure at each iteration, an O(log n) operation, making the whole
loop O(n log n).  If you sort a set (which is O(n log n)) inside the
loop then you end up with O(n**2 log n) which is impractical.  A
reason you might sort inside the loop might be to find the nearby
neighbors of the new element or traverse some elements in the middle.
This is trivial with a tree structure but messy with something like
sets.


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 04:39:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 08:39:19 GMT
Subject: No trees in the stdlib?
References: <mailman.2139.1245994218.8015.python-list@python.org>
	<h21mgt$oav$1@panix3.panix.com>
	<mailman.2140.1245996088.8015.python-list@python.org>
	<h2f7ba$njc$5@lust.ihug.co.nz>
	<mailman.2446.1246491262.8015.python-list@python.org>
	<h2ke9k$os8$3@lust.ihug.co.nz>
Message-ID: <025db552$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 20:08:20 +1200, Lawrence D'Oliveiro wrote:

> In message <mailman.2446.1246491262.8015.python-list at python.org>, Jo?o
> Valverde wrote:
> 
>> Lawrence D'Oliveiro wrote:
[...]
>>> Want sorted order?
>>>
>>>     sorted(tuple(the_set))
>>>
>>> What could be simpler?
>> 
>> Try putting that inside a loop with thousands of iterations and you'll
>> see what the problem is.
> 
> You could apply the same argument to anything. E.g. why create a tree
> structure with a million elements? Try putting that inside a loop with
> thousands of iterations and you'll see what the problem is.

The difference is, it's vanishingly rare to want to build a tree with 
millions of elements thousands of times over and over again, but it is 
not unreasonable to want to access sorted data thousands of times. 
Needing to re-sort it over and over and over again is wasteful, slow and 
stupid. Binary trees were invented, in part, specifically to solve this 
use-case.



-- 
Steven


From http  Fri Jul  3 04:39:27 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 01:39:27 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
	<025db26e$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xk52qgny8.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> groupby() works on lists.

>>> a = [1,3,4,6,7]
>>> from itertools import groupby
>>> b = groupby(a, lambda x: x%2==1)  # split into even and odd
>>> c = list(b)
>>> print len(c)
3
>>> d = list(c[1][1])    # should be [4,6]
>>> print d  # oops.
[]

> The difference between what I'm suggesting and what groupby() does is 
> that my suggestion would collate *all* the elements with the same key, 
> not just runs of them. This (as far as I can tell) requires returning 
> lists rather than iterators.

I guess that is reasonable.

> The most important difference between my suggestion and that of the OP is 
> that he limited the key function to something which returns a truth 
> value, while I'm looking for something more general which can split the 
> input into an arbitrary number of collated sublists.

Also ok.


From pyklass at gmail.com  Fri Jul  3 04:55:04 2009
From: pyklass at gmail.com (Goksie Aruna)
Date: Fri, 03 Jul 2009 09:55:04 +0100
Subject: is it possible to write USSD / SMS /SS7 apps in python
Message-ID: <4A4DC768.40604@gmail.com>

Can someone give me an insight into these?

    developing ss7 or USSD or SMS apps in python.

is there any existing ones in this manner?

Thanks





From tsangpo.newsgroup at gmail.com  Fri Jul  3 05:03:51 2009
From: tsangpo.newsgroup at gmail.com (tsangpo)
Date: Fri, 3 Jul 2009 17:03:51 +0800
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
	<nfi3m.2341$ze1.1151@news-server.bigpond.net.au>
Message-ID: <h2khkq$159j$1@adenine.netfront.net>

Just a shorter implementation:

from itertools import groupby
def split(lst, func):
    gs = groupby(lst, func)
    return list(gs[True]), list(gs[False])


"Lie Ryan" <lie.1296 at gmail.com> ????????????:nfi3m.2341$ze1.1151 at news-server.bigpond.net.au...
> Brad wrote:
>> On Jul 2, 9:40 pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>>> If it is speed that we are after, it's my understanding that map and
>>> filter are faster than iterating with the for statement (and also
>>> faster than list comprehensions).  So here is a rewrite:
>>>
>>> def split(seq, func=bool):
>>>         t = filter(func, seq)
>>>         f = filter(lambda x: not func(x), seq)
>>>         return list(t), list(f)
>>>
>>
>> In my simple tests, that takes 1.8x as long as the original solution.
>> Better than the itertools solution, when "func" is short and fast. I
>> think the solution here would worse if func was more complex.
>>
>> Either way, what I am still wondering is if people would find a built-
>> in implementation useful?
>>
>> -Brad
>
> A built-in/itertools should always try to provide the general solution
> to be as useful as possible, something like this:
>
> def group(seq, func=bool):
>    ret = {}
>    for item in seq:
>        fitem = func(item)
>        try:
>            ret[fitem].append(item)
>        except KeyError:
>            ret[fitem] = [item]
>    return ret
>
> definitely won't be faster, but it is a much more general solution.
> Basically, the function allows you to group sequences based on the
> result of func(item). It is similar to itertools.groupby() except that
> this also group non-contiguous items. 




From usernet at ilthio.net  Fri Jul  3 05:07:30 2009
From: usernet at ilthio.net (Tim Harig)
Date: Fri, 03 Jul 2009 09:07:30 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xws6qrgy5.fsf@ruckus.brouhaha.com>
	<ZT83m.1774$cl4.0@flpi150.ffdc.sbc.com>
	<7xocs2222d.fsf@ruckus.brouhaha.com>
	<_ia3m.3614$Jb1.3478@flpi144.ffdc.sbc.com>
	<025db066$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <mTj3m.2213$Wj7.1361@nlpi065.nbdc.sbc.com>

On 2009-07-03, Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
> On Thu, 02 Jul 2009 22:14:18 +0000, Tim Harig wrote:
>> On 2009-07-02, Paul Rubin <http> wrote:
>>> Tim Harig <usernet at ilthio.net> writes:
>>>> If lower is 5 and higher is 3, then it returns 3 because 3 != None in
>>>> the first if.
>>> Sorry, the presumption was that lower <= higher, i.e. the comparison
>>> had already been made and the invariant was enforced by the class
>>> constructor.  The comment should have been more explicit, I guess.
>> That being the case, it might be a good idea either to handle the
>> situation and raise an exception or add:
>> assert self.lower <= self.higher
> Only if you want strange and mysterious bugs whenever somebody runs your 
> code with the -O flag.

The point here is that Rubin presumed that the condition where lower >
higher should never exist.  Therefore, because the program given segment of
program doesn't test it elswhere, it is possible that a bug in the code
that sets lower > higher could go unoticed while silently passing the wrong
data.

Therefore, It is better to test that assumption in a way that *will* crash
if something is wrong, for instance, if another method accidently changes
one of the values.  That would tend to make errors in another method of the
class (or even higher up in this method), more likely to be found.

> asserts are disabled when the -O flag is given.

Right, like defining NDEBUG in C.  In _Writing Solid Code_ by Steve
Maguire, he likens it to having two pieces of code: one for testing where
any errors should cause crashes as early as possible and one for shipping
where it may be better to handle errors if possible from within the code.

> You should never use asserts for testing data. That's not what they're 
> for. They're for testing program logic (and unit-testing).

What I am suggesting here is exactly that.  If lower is always defined such
that it should always be equal to or lower then higher, then there is an
error in the code somewhere if lower is higher by the time this code is
called.  Either the constructor didn't didn't reject input properly or
another method within the class has inadvertantly changed higher or lower
in an uncorrect way.

In any event, whether I am using it 100% correctly, I want to find any
errors in my code.  If there is an error, I want the program to crash
during testing rather then silently passing bad data.  assert will help
here.

Unfortunatly, Rubin is right.  I did make the mistake that the assert will
fail with higher or lower values of None, which is allowed here.  The same
basic premise is correct but will require more complex assertions to allow
that through.


From mjohnson at cfi.co.ug  Fri Jul  3 05:18:04 2009
From: mjohnson at cfi.co.ug (Johnson Mpeirwe)
Date: Fri, 03 Jul 2009 12:18:04 +0300
Subject: PSP Caching
Message-ID: <4A4DCCCC.6040605@cfi.co.ug>

Hello All,

How do I stop caching of Python Server Pages (or whatever causes changes 
in a page not to be noticed in a web browser)? I am new to developing 
web applications in Python and after looking at implementations of PSP 
like Spyce (which I believed introduces new unnecessary non-PSP syntax), 
I decided to write my own PSP applications from scratch. When I modify a 
file, I keep getting the old results until I intentionally introduce an 
error (e.g parse error) and correct it after to have the changes 
noticed. There's no proxy (I am working on a windows machine unplugged 
from the network). I have Googled and no documents seem to talk about 
this. Is there any particular mod_python directive I must set in my 
Apache configuration to fix this?

Any help will be highly appreciated.

Johnson


From clp2 at rebertia.com  Fri Jul  3 05:21:33 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 3 Jul 2009 02:21:33 -0700
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <4A4DC768.40604@gmail.com>
References: <4A4DC768.40604@gmail.com>
Message-ID: <50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>

On Fri, Jul 3, 2009 at 1:55 AM, Goksie Aruna<pyklass at gmail.com> wrote:
> Can someone give me an insight into these?
>
> ? developing ss7 or USSD or SMS apps in python.
>
> is there any existing ones in this manner?

Advice for the future: STFW.

http://pypi.python.org/pypi?%3Aaction=search&term=sms&submit=search

Cheers,
Chris
-- 
http://blog.rebertia.com


From pyklass at gmail.com  Fri Jul  3 05:31:38 2009
From: pyklass at gmail.com (Goke Aruna)
Date: Fri, 3 Jul 2009 10:31:38 +0100
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
Message-ID: <30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>

On Fri, Jul 3, 2009 at 10:21 AM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Fri, Jul 3, 2009 at 1:55 AM, Goksie Aruna<pyklass at gmail.com> wrote:
> > Can someone give me an insight into these?
> >
> >   developing ss7 or USSD or SMS apps in python.
> >
> > is there any existing ones in this manner?
>
> Advice for the future: STFW.
>
> http://pypi.python.org/pypi?%3Aaction=search&term=sms&submit=search
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>


thanks Chris,

however, i have checked all the packages there are specifics for a
particular company or device.

what am saying is reading the ITU info on USSD, is it possible to use python
to write the application SS7 with support for TCAP/MAP talking to E1 card to
do the ss7 signalling.

Thanks.

goksie
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/09ad06f7/attachment-0001.html>

From kurt.alfred.mueller at gmail.com  Fri Jul  3 05:38:48 2009
From: kurt.alfred.mueller at gmail.com (yam850)
Date: Fri, 3 Jul 2009 02:38:48 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org> 
	<e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com>
Message-ID: <58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com>

On 1 Jul., 21:30, spillz <damienlmo... at gmail.com> wrote:
> On Jun 29, 3:15 pm, Pascal Chambon <chambon.pas... at gmail.com> wrote:
> > I've had real issues with subprocesses recently : from a python script,
> > on windows, I wanted to "give control" to a command line utility, i.e
> > forward user in put to it and display its output on console. It seems
> > simple, but I ran into walls :
> If you are willing to have a wxPython dependency, wx.Execute handles
> non-blockingi/o with processes on all supported platforms

I made a python method/function for non blocking read from a file
object.
I use it in one of my python programs.
When looking at the code bear in mind that I am not an expert and I am
happy to see comments.

#------------------------------------------------------------------
def non_blocking_readline(f_read=sys.stdin, timeout_select=0.0):
    """to readline non blocking from the file object 'f_read'
       for 'timeout_select' see module 'select'"""
    import select
    text_lines = ''                       # empty string
    while True:                           # as long as there are bytes
to read
        try:                              # try select
            rlist, wlist, xlist = select.select([f_read], [], [],
timeout_select)
        except:                           # select ERROR
            print >>sys.stderr, ("non_blocking_read select ERROR")
            break
        if DEBUG: print("rlist=%s, wlist=%s, xlist=%s" % (repr(rlist),
repr(wlist), repr(xlist)))
        if  len(rlist) > 0:
            text_read = f_read.readline() # get a line
            if DEBUG: print("after read/readline text_read:'%s', len=
%s" % (text_read, repr(len(text_read))))
            if  len(text_read) > 0:       # there were some bytes
                text_lines = "".join([text_lines, text_read])
                if DEBUG: print("text_lines:'%s'" % (text_lines))
            else:
                break                     # there was no byte in a
line
        else:
            break                         # there was no byte in the
f_read
    if  text_lines  ==  '':
        return None
    else:
        return text_lines


--
Kurt


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 05:50:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 09:50:09 GMT
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
	<025db26e$0$20657$c3e8da3@news.astraweb.com>
	<7xk52qgny8.fsf@ruckus.brouhaha.com>
Message-ID: <025dc5ec$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 01:39:27 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> groupby() works on lists.
> 
>>>> a = [1,3,4,6,7]
>>>> from itertools import groupby
>>>> b = groupby(a, lambda x: x%2==1)  # split into even and odd 
>>>> c = list(b)
>>>> print len(c)
> 3
>>>> d = list(c[1][1])    # should be [4,6] print d  # oops.
> []

I didn't say it worked properly *wink*

Seriously, this behaviour caught me out too. The problem isn't that the 
input data is a list, the same problem occurs for arbitrary iterators. 
>From the docs:

[quote]
The operation of groupby() is similar to the uniq filter in Unix. It 
generates a break or new group every time the value of the key function 
changes (which is why it is usually necessary to have sorted the data 
using the same key function). That behavior differs from SQL?s GROUP BY 
which aggregates common elements regardless of their input order.

The returned group is itself an iterator that shares the underlying 
iterable with groupby(). Because the source is shared, when the groupby() 
object is advanced, the previous group is no longer visible. So, if that 
data is needed later, it should be stored as a list
[end quote]

http://www.python.org/doc/2.6/library/itertools.html#itertools.groupby




-- 
Steven


From petshmidt at googlemail.com  Fri Jul  3 06:28:25 2009
From: petshmidt at googlemail.com (Tep)
Date: Fri, 3 Jul 2009 03:28:25 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com>
	<mailman.2451.1246492584.8015.python-list@python.org>
	<02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com>
	<9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com> 
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>
Message-ID: <46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com>

On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> On Jul 2, 4:31?am, Tep <petshm... at googlemail.com> wrote:
>
>
>
>
>
> > On 2 Jul., 10:25, Tep <petshm... at googlemail.com> wrote:
>
> > > On 2 Jul., 01:56, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > > someone wrote:
> > > > > Hello,
>
> > > > > how can I replace '?' sign from string? Or do split at that character?
> > > > > Getting unicode error if I try to do it:
>
> > > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position
> > > > > 1: ordinal not in range(128)
>
> > > > > Thanks, Pet
>
> > > > > script is # -*- coding: UTF-8 -*-
>
> > > > It sounds like you're mixing bytestrings with Unicode strings. I can't
> > > > be any more helpful because you haven't shown the code.
>
> > > Oh, I'm sorry. Here it is
>
> > > def cleanInput(input)
> > > ? ? return input.replace('?', '')
>
> > I also need:
>
> > #input is html source code, I have problem with only this character
> > #input = 'foo ? bar'
> > #return should be foo
> > def splitInput(input)
> > ? ? parts = input.split(' ? ')
> > ? ? return parts[0]
>
> > Thanks!
>
> Okay people want to help you but you must make it easy for us.
>
> Post again with a small piece of code that is runnable as-is and that
> causes the traceback you're talking about, AND post the complete
> traceback too, as-is.
>
> I just tried a bit of your code above in my interpreter here and it
> worked fine:
>
> |>>> data = 'foo ? bar'
> |>>> data.split('?')
> |['foo ', ' bar']
> |>>> data = u'foo ? bar'
> |>>> data.split(u'?')
> |[u'foo ', u' bar']
>
> Figure out the smallest piece of "html source code" that causes the
> problem and include that with your next post.

The problem was, I've converted "html source code" to unicode object
and didn't encoded to utf-8 back, before using split...
Thanks for help and sorry for not so smart question
Pet

>
> HTH,
> ~Simon
>
> You might also read this:http://catb.org/esr/faqs/smart-questions.html



From jeanmichel at sequans.com  Fri Jul  3 06:33:45 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 03 Jul 2009 12:33:45 +0200
Subject: question of style
In-Reply-To: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <4A4DDE89.1080003@sequans.com>

Simon Forman wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
>   
Easier for you but not for those who are familiar with the standard way 
of python coding. (by standard I don't mean the "only Godly way of 
coding", there's room for custom rules)
But I think most of the people will write:
if self.higher is None:
    return self.lower
if self.lower is None:
    return self.higher
# here neither are None

> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
>
> ## First snippet
>
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
>
> ## Second snippet
>
> if self.higher is None:
>     if self.lower is None:
>         return
>     return self.lower
> if self.lower is None:
>     return self.higher
>
> What do you think?
>
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)
>   



From hkmshb at gmail.com  Fri Jul  3 06:46:32 2009
From: hkmshb at gmail.com (Klone)
Date: Fri, 3 Jul 2009 03:46:32 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
Message-ID: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>

Hi all. I believe in programming there is a common consensus to avoid
code duplication, I suppose such terms like 'DRY' are meant to back
this idea. Anyways, I'm working on a little project and I'm using TDD
(still trying to get a hang of the process) and am trying to test the
functionality within a method. Whoever it so happens to verify the
output from the method I have to employ the same algorithm within the
method to do the verification since there is no way I can determine
the output before hand.

So in this scenario is it OK to duplicate the algorithm to be tested
within the test codes or refactor the method such that it can be used
within test codes to verify itself(??).


From bthate at gmail.com  Fri Jul  3 06:50:36 2009
From: bthate at gmail.com (Bart Thate)
Date: Fri, 3 Jul 2009 03:50:36 -0700 (PDT)
Subject: GOZERBOT 0.9.1 BETA2 released
Message-ID: <67b84335-211d-4f7f-b417-71faeb70fbf5@o6g2000yqj.googlegroups.com>

GOZERBOT has a new website !! check it out at http://gozerbot.org.
This is all in preparation for the 0.9.1 release and the latest
GOZERBOT beta has been released as well. Please try this version and
let me know how goes.

Install is as simple as .. easy_install gozerbot gozerplugs, see
README.

This release will be used to move GOZERBOT 0.9 into the debian
repositories and freebsd ports.

we can be contacted on #dunkbots EFNET/IRCNET or use http://dev.gozerbot.org
for any bugs you might find.

NEW IN THIS RELEASE:

* GOZERBOT is now truely free as it no longer depends on GPL licensed
xmpppy, a own xmpp package has been implemented for this.

* GOZERBOT now depends on setuptools to install the proper packages

* gozerbot-nest script can be used to install all dependacies and bot
code in 1 directory that can be run by the user (no root required)

* morphs are added that allow for encryption of input and output
streams (not used yet)

ABOUT GOZERBOT:

GOZERBOT is a channel bot that aids with conversation in irc channels
and jabber conference rooms. its mainly used to serve rss feeds and to
have custom commands made for the channel. More then just a channel
bot GOZERBOT aims to provide a platform for the user to program his
own bot and make it into something thats usefull. This is done with a
plugin structure that makes it easy to program your own. But GOZERBOT
comes with some batteries included, there are now over 100 plugins
already written and ready for use.

groet,

Bart


From p.f.moore at gmail.com  Fri Jul  3 07:01:04 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Fri, 3 Jul 2009 12:01:04 +0100
Subject: Sequence splitting
In-Reply-To: <c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
Message-ID: <79990c6b0907030401w2e668ac3qd315c751d9e3e924@mail.gmail.com>

2009/7/3 Brad <schickb at gmail.com>:
> Perhaps true, but it would be a nice convenience (for me) as a built-
> in written in either Python or C. Although the default case of a bool
> function would surely be faster.

The chance of getting this accepted as a builtin is essentially zero.
To be a builtin, as opposed to being in the standard library,
something has to have a very strong justification.

This suggestion may find a home in the standard library, although it's
not entirely clear where (maybe itertools, although it's not entirely
obvious that it's a fit there).

You'd have to justify this against the argument "not every 2-3 line
function needs to be built in". Personally, I'm not sure it passes
that test - sure, it's a useful function, but it's not that hard to
write when you need it. It may be better as a recipe in the cookbook.
Or if it's close enough to the spirit of the itertools, it may be
suitable as a sample in the itertools documentation (the "recipes"
section).

Paul.


From user at example.net  Fri Jul  3 07:21:12 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 13:21:12 +0200
Subject: stringio+tarfile
In-Reply-To: <mailman.2533.1246588607.8015.python-list@python.org>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<mailman.2533.1246588607.8015.python-list@python.org>
Message-ID: <4a4de9a8$0$1105$4fafbaef@reader3.news.tin.it>

> First problem I see is all those numbers before the lines.  That's not 
> valid python.
> 
> Assuming that was a transcription error

not so. i intentionally add linenumbers to facilitare reference to the 
code, but if it is a nuisance i will not include them anymore.

thanks


From tkjthingone at gmail.com  Fri Jul  3 07:28:47 2009
From: tkjthingone at gmail.com (Horace Blegg)
Date: Fri, 3 Jul 2009 04:28:47 -0700
Subject: pep 8 constants
In-Reply-To: <BN23m.2219$ze1.1708@news-server.bigpond.net.au>
References: <mailman.7174.1231915778.3487.python-list@python.org>
	<49a50517$0$3567$426a74cc@news.free.fr> <4A477991.4050109@harvee.org>
	<op.uv89h1xqa8ncjz@gnudebst> <4A484C07.9050800@harvee.org>
	<4A48A495.7040504@tim.thechases.com> <4A48E307.50804@harvee.org>
	<4A49E232.6090101@tim.thechases.com>
	<mailman.2392.1246375713.8015.python-list@python.org>
	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>
Message-ID: <b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>

I've been kinda following this. I have a cousin who is permanently wheel
chair bound and doesn't have perfect control of her hands, but still manages
to use a computer and interact with society. However, the idea/thought of
disabled programmers was new to me/hadn't ever occurred to me.

You say that using your hands is painful, but what about your feet? Wouldn't
it be possible to rig up some kind of foot peddle for shift/caps lock? Kinda
like the power peddle used with sowing machines, so the hands are free to
hold fabric.

I don't mean this in a condescending manor, and I apologize if you take it
as such. I'm genuinely curious if you think something like this could work.

The way I was envisioning it working last night (and I haven't the faintest
clue how SR works, nor have I ever used SR) was that you would hit the foot
peddle, which would tell the SR program to capitalize the first letter of
the next word (a smart shift, basically, so you don't end up doing something
like ... WONderland -or- "stocks are up 1,0))% TOday".)

Possible? Stupid?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/d558cf34/attachment-0001.html>

From ricli85 at gmail.com  Fri Jul  3 07:29:44 2009
From: ricli85 at gmail.com (Rickard Lindberg)
Date: Fri, 3 Jul 2009 13:29:44 +0200
Subject: Is code duplication allowed in this instance?
In-Reply-To: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <890d8ab70907030429i615c4bdat2263ac9555bd8c4e@mail.gmail.com>

> Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine
> the output before hand.

Can you clarify this scenario a bit?

If you are performing black-box testing I don't see why you need to
use the same algorithm in the test code. But maybe your case is
special. On the other hand you can not perform black-box testing if
the output is not known for a given input.

-- 
Rickard Lindberg


From user at example.net  Fri Jul  3 07:29:52 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 13:29:52 +0200
Subject: stringio+tarfile
In-Reply-To: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <4a4debb1$0$1106$4fafbaef@reader3.news.tin.it>

thanks to the guys who bothered to answer me even using their chrystal 
ball ;-)

i'll try to be more specific.

yes: i want to create a tar file in memory, and add some content from a
memory buffer...

my platform:

$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
$ python -V
Python 2.3.4

following some suggestions i modified the code:

$ cat tar001.py
import tarfile
import StringIO
sfo1 = StringIO.StringIO("one\n")
sfo2 = StringIO.StringIO("two\n")
tfo = StringIO.StringIO()
tar = tarfile.open(fileobj=tfo , mode="w")
ti = tar.gettarinfo(fileobj=tfo)
for sfo in [sfo1 , sfo2]:
     tar.addfile(fileobj=sfo , tarinfo=ti)
print tfo

and that's what i get:

$ python tar001.py > tar001.out
Traceback (most recent call last):
   File "tar001.py", line 7, in ?
     ti = tar.gettarinfo(fileobj=tfo)
   File "/usr/lib/python2.3/tarfile.py", line 1060, in gettarinfo
     name = fileobj.name
AttributeError: StringIO instance has no attribute 'name'

can you help?

TIA

ps: i'd also like that the tar file has names for the buffers, so than 
once output the file can be untarred with /bin/tar into regular files...


From eckhardt at satorlaser.com  Fri Jul  3 07:58:44 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Fri, 03 Jul 2009 13:58:44 +0200
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
Message-ID: <kc81i6-l85.ln1@satorlaser.homedns.org>

Thanks to all that answered, in particular I wasn't aware of the existence
of the __del__ function.

For completeness' sake, I think I have found another way to not really solve
but at least circumvent the problem: weak references. If I understand
correctly, those would allow me to pass out handles to the resources and,
if some code decides it is time, release the resources and render all the
weak references invalid. At least I don't suffer resource leaks but rather
get meaningful errors that way, which is enough for my case.

cheers!

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From __peter__ at web.de  Fri Jul  3 08:12:38 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 03 Jul 2009 14:12:38 +0200
Subject: stringio+tarfile
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<4a4debb1$0$1106$4fafbaef@reader3.news.tin.it>
Message-ID: <h2ksj9$g38$00$1@news.t-online.com>

superpollo wrote:

> thanks to the guys who bothered to answer me even using their chrystal
> ball ;-)
> 
> i'll try to be more specific.
> 
> yes: i want to create a tar file in memory, and add some content from a
> memory buffer...
> 
> my platform:
> 
> $ uname -a
> Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
> $ python -V
> Python 2.3.4
> 
> following some suggestions i modified the code:
> 
> $ cat tar001.py
> import tarfile
> import StringIO
> sfo1 = StringIO.StringIO("one\n")
> sfo2 = StringIO.StringIO("two\n")
> tfo = StringIO.StringIO()
> tar = tarfile.open(fileobj=tfo , mode="w")
> ti = tar.gettarinfo(fileobj=tfo)

gettarinfo() expects a real file, not a file-like object.
You have to create your TarInfo manually.

> for sfo in [sfo1 , sfo2]:
>      tar.addfile(fileobj=sfo , tarinfo=ti)
> print tfo
> 
> and that's what i get:
> 
> $ python tar001.py > tar001.out
> Traceback (most recent call last):
>    File "tar001.py", line 7, in ?
>      ti = tar.gettarinfo(fileobj=tfo)
>    File "/usr/lib/python2.3/tarfile.py", line 1060, in gettarinfo
>      name = fileobj.name
> AttributeError: StringIO instance has no attribute 'name'
> 
> can you help?

I recommend that you have a look into the tarfile module's source code.

The following seems to work:

import sys
import time
import tarfile
import StringIO

sf1 = "first.txt", StringIO.StringIO("one one\n")
sf2 = "second.txt", StringIO.StringIO("two\n")
tf = StringIO.StringIO()

tar = tarfile.open(fileobj=tf , mode="w")

mtime = time.time()
for name, f in [sf1 , sf2]:
    ti = tarfile.TarInfo(name)
    ti.size = f.len
    ti.mtime = mtime
    # add more attributes as needed 
    tar.addfile(ti, f)

sys.stdout.write(tf.getvalue())

Peter



From sri_annauni at yahoo.co.in  Fri Jul  3 08:15:47 2009
From: sri_annauni at yahoo.co.in (srinivasan srinivas)
Date: Fri, 3 Jul 2009 17:45:47 +0530 (IST)
Subject: Python debugger
Message-ID: <740981.83964.qm@web7901.mail.in.yahoo.com>


Hi,
Could you suggest some python debuggers?

Thanks,
Srini


      Love Cricket? Check out live scores, photos, video highlights and more. Click here http://cricket.yahoo.com


From jackdied at gmail.com  Fri Jul  3 08:34:01 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Fri, 3 Jul 2009 08:34:01 -0400
Subject: Searching equivalent to C++ RAII or deterministic destructors
In-Reply-To: <6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>
Message-ID: <b8e622740907030534s7f57d686g9f4eb956962bef00@mail.gmail.com>

On Thu, Jul 2, 2009 at 2:36 PM, Carl Banks<pavlovevidence at gmail.com> wrote:
> On Jul 2, 3:12?am, Ulrich Eckhardt <eckha... at satorlaser.com> wrote:
>> Bearophile wrote:
>> > Ulrich Eckhardt:
>> >> a way to automatically release the resource, something
>> >> which I would do in the destructor in C++.
>>
>> > Is this helpful?
>> >http://effbot.org/pyref/with.htm
>>
>> Yes, it aims in the same direction. However, I'm not sure this applies to my
>> case. The point is that the resource handle is not just used locally in a
>> restricted scope but it is allocated and stored. The 'with' is something
>> that makes sense in the context of mutex locking, where you have a
>> well-defined critical section. What I need is something similar to open(),
>> which returs a file. When the last reference to that object goes out of
>> scope, the underlying file object is closed.
>
> On CPython you can do it with a __del__ attribute.
>
> Warning: objects with a __del__ attribute prevent reference cycle
> detection, which can potentially lead to memory (and resource) leaks.
> So you must be careful to avoid creating reference loops with that
> object.

WARNING-er: As Carl points out, adding a __del__ method actually makes
it /less/ likely that your object will be cleaned up.  __del__ is only
useful if you have a complicated tear-down procedure.  Since you come
from C++ RAII land (my old haunt) your objects probably only allocate
one resource each, or worse: a bunch of objects that allocate one
resource each.  In that case __del__ will always hurt you.

The C++ temptation is to match every __init__ with a __del__.  A
better rule of thumb is to only add a __del__ method after confirming
with someone else that it would be useful.  Better still is to ask
them by postal courier.  For best results that someone should be your
grandmother.

> Note that file objects have a close method; you can explicitly close
> it at any time. ?Your object should follow that example, and define a
> close (or release, or whatever) method. ?I'd recommend making an
> effort to call it and to rely on __del__ as little as possible.

This.  If you care enough about a resource to write a __del__ method
you care enough to clean it up explicitly.  'with' blocks are very
nice for that.


-jack


From tn.pablo at gmail.com  Fri Jul  3 08:34:20 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Fri, 3 Jul 2009 07:34:20 -0500
Subject: Sequence splitting
In-Reply-To: <79990c6b0907030401w2e668ac3qd315c751d9e3e924@mail.gmail.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<79990c6b0907030401w2e668ac3qd315c751d9e3e924@mail.gmail.com>
Message-ID: <fdd00b510907030534j1cbfb11dx72b52c6265452dbe@mail.gmail.com>

On Fri, Jul 3, 2009 at 06:01, Paul Moore<p.f.moore at gmail.com> wrote:
> 2009/7/3 Brad <schickb at gmail.com>:
>> Perhaps true, but it would be a nice convenience (for me) as a built-
>> in written in either Python or C. Although the default case of a bool
>> function would surely be faster.
>
> The chance of getting this accepted as a builtin is essentially zero.
> To be a builtin, as opposed to being in the standard library,
> something has to have a very strong justification.

That's right.  Mr. schickb, I think what you need is a few concrete
examples as to where this function would be beneficial, so it can be
judged objectively.

-- 
Pablo Torres N.


From bieffe62 at gmail.com  Fri Jul  3 08:34:27 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Fri, 3 Jul 2009 05:34:27 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <b0b2ff61-9023-474c-b114-863107781971@y7g2000yqa.googlegroups.com>

On Jul 3, 12:46?pm, Klone <hkm... at gmail.com> wrote:
> Hi all. I believe in programming there is a common consensus to avoid
> code duplication, I suppose such terms like 'DRY' are meant to back
> this idea. Anyways, I'm working on a little project and I'm using TDD
> (still trying to get a hang of the process) and am trying to test the
> functionality within a method. Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine
> the output before hand.
>
> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

If the purpose of the test is to verify the algorithm, you obviously
should not use the algorithm
to verify itself ... you should use a  set of pairs (input data,
exoected output data) data that you know is
well representative of the data your algorithm will process. Possibly
to prepare the test data set
you might need a  different - and already proven - implementation of
the algorithm.

Another thing I sometime do when testing mathematics function is use
counter-proof: for instance, if my function
computes the roots of a quadratic equation, the test verifies that the
roots applied to the equation
actually give (almost) zero as result. This kind of test might not be
as rigorous as preparing the data set with the known
answers, but it is easier to setup and could give you a first idea if
your code is "correct enough" to stand
more formal proof.

Ciao
----
FB


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 08:46:08 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 14:46:08 +0200
Subject: Python debugger
In-Reply-To: <mailman.2555.1246623750.8015.python-list@python.org>
References: <mailman.2555.1246623750.8015.python-list@python.org>
Message-ID: <4a4dfd78$0$404$426a74cc@news.free.fr>

srinivasan srinivas a ?crit :
> Hi,
> Could you suggest some python debuggers?

http://docs.python.org/library/pdb.html#module-pdb

HTH


From lie.1296 at gmail.com  Fri Jul  3 08:49:21 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 12:49:21 GMT
Subject: Is code duplication allowed in this instance?
In-Reply-To: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <l7n3m.2388$ze1.2120@news-server.bigpond.net.au>

Klone wrote:
> Hi all. I believe in programming there is a common consensus to avoid
> code duplication, I suppose such terms like 'DRY' are meant to back
> this idea. Anyways, I'm working on a little project and I'm using TDD
> (still trying to get a hang of the process) and am trying to test the
> functionality within a method. Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine
> the output before hand.
> 
> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

When unittesting a complex output, usually the first generation code
would generate the output and then you (manually) verify this output and
copy the output to the test code. The testing code should be as dumb as
possible to avoid bugs in the testing code itself. The most important
thing is not to use a possibly buggy algorithm implementation to check
the algorithm itself. If your test code looks like this:

# this the function to be tested
def func(a, b):
    return a + b

class TC(unittest.TestCase):
    def test_foo(self):
        a, b = 10, 20 # worse: use random module
        result = a + b
        self.assertEqual(func(a, b), result)

then something is definitely wrong. Instead the testing code should be
simple and stupid like:

class TC(unittest.TestCase):
    def test_foo(self):
        self.assertEqual(func(10, 20), 30)

There are exceptions though, such as if you're 100% sure your
first-generation program is correct and you simply want to replicate the
same function with different algorithm, or probably optimizing the
function. For that case, you could do something like this:

def func(a, b):
    # some fancy new algo
    pass
class TC(unittest.TestCase):
    def original_func(self, a, b):
        return a + b
    def test_foo(self):
        self.assertEquals(func(a, b), self.original_func(a, b))


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 08:50:10 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 14:50:10 +0200
Subject: Adding an object to the global namespace through " f_globals"
	is that allowed ?
In-Reply-To: <mailman.2452.1246493871.8015.python-list@python.org>
References: <mailman.2452.1246493871.8015.python-list@python.org>
Message-ID: <4a4dfe6a$0$404$426a74cc@news.free.fr>

Stef Mientki a ?crit :
> hello,
> 
> I need to add an object's name to the global namespace.
> The reason for this is to create an environment,
> where you can add some kind of math environment,
> where no need for Python knowledge is needed.
> 
> The next statement works,
> but I'm not sure if it will have any dramatical side effects,
> other than overruling a possible object with the name A
> 
> def some_function ( ...) :
>      A = object ( ...)
>      sys._getframe(1).f_globals [ Name ] = A
> 
> 

Anything wrong with the 'global' statement ?

Python 2.5.2 (r252:60911, Oct  5 2008, 19:24:49)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
pythonrc start
pythonrc done
 >>> def foo():
...     global a
...     a = 42
...
 >>> a
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
NameError: name 'a' is not defined
 >>> foo()
 >>> a
42
 >>>




From ziade.tarek at gmail.com  Fri Jul  3 08:57:19 2009
From: ziade.tarek at gmail.com (=?ISO-8859-1?Q?Tarek_Ziad=E9?=)
Date: Fri, 3 Jul 2009 14:57:19 +0200
Subject: PEP 376
In-Reply-To: <EF743CC8-5AFE-47F5-97A9-AF993BD4B6C7@declareSub.com>
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net> <4A4C685A.8020300@Strombergson.com>
	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
	<1f63m.2229$ze1.1410@news-server.bigpond.net.au>
	<EF743CC8-5AFE-47F5-97A9-AF993BD4B6C7@declareSub.com>
Message-ID: <94bdd2610907030557q79cf7018t77c39beb6f45437b@mail.gmail.com>

Ok here's my proposal for the checksum :

- I'll add the "hash_type:" suffix in the record file

- install will get a new option to define what hash should be used
when writing the RECORD file
  it will default to SHA1 for 2.7/3.2

- pkgutil, that reads the RECORD files, will pick the right hash
function by looking at the suffix

now for the security it's another story that goes beyond the scope of this PEP
notice though, that the PEP provides a place-holder for distributions metadata,
so it could host a key later on.


On Thu, Jul 2, 2009 at 8:00 PM, Charles Yeomans<charles at declaresub.com> wrote:
>
> On Jul 2, 2009, at 1:37 PM, Lie Ryan wrote:
>
>> Joachim Str?mbergson wrote:
>>>
>>> Aloha!
>>>
>>> Tarek Ziad? wrote:
>>>>
>>>> The prefix is a good idea but since it's just a checksum to control
>>>> that the file hasn't changed
>>>> what's wrong with using a weak hash algorithm like md5 or now sha1 ?
>>>
>>> Because it creates a dependency to an old algorithm that should be
>>> deprecated. Also using MD5, even for a thing like this might make people
>>> belive that it is an ok algorithm to use - "Hey, it is used by the
>>> default install in Python, so it must be ok, right?"
>>>
>>> If we flip the argument around: Why would you want to use MD5 instead of
>>> SHA-256? For the specific use case the performance will not (should not)
>>> be an issue.
>>>
>>> As I wrote a few mails ago, it is time to move forward from MD5 and
>>> designing something in 2009 that will be around for many years that uses
>>> MD5 is (IMHO) a bad design decision.
>>>
>>>> If someone wants to modify a file of a distribution he can recreate
>>>> the checksum as well,
>>>> the only secured way to prevent that would be to use gpg keys but
>>>> isn't that overkill for what we need ?
>>>
>>> Actually, adding this type of security would IMHO be a good idea.
>>>
>>
>> Now, are we actually talking about security or checksum?
>>
>> It has been known for years that MD5 is weak, weak, weak. Not just in
>> the recent years. But it doesn't matter since MD5 was never designed for
>> security, MD5 was designed to protect against random bits corruption. If
>> you want security, look at least to GPG. For data protection against
>> intentional, malicious forging, definitely MD5 is the wrong choice. But
>> when you just want a simple checksum to ensure that a faulty router
>> somewhere in the internet backbone doesn't destroying your data, MD5 is
>> a fine algorithm.
>> --
>
> On the contrary, MD5 was intended to be a cryptographic hash function, not a
> checksum.
>
> Charles Yeomans
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Tarek Ziad? | http://ziade.org


From nosklo at gmail.com  Fri Jul  3 08:57:35 2009
From: nosklo at gmail.com (Clovis Fabricio)
Date: Fri, 3 Jul 2009 09:57:35 -0300
Subject: Python debugger
In-Reply-To: <740981.83964.qm@web7901.mail.in.yahoo.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
Message-ID: <9187a60d0907030557q69a2429cn509e3792ed7708be@mail.gmail.com>

2009/7/3 srinivasan srinivas <sri_annauni at yahoo.co.in>:
> Could you suggest some python debuggers?

Two graphical debugger frontends:

http://www.gnu.org/software/emacs/
http://winpdb.org/


From lie.1296 at gmail.com  Fri Jul  3 09:10:34 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 13:10:34 GMT
Subject: Sequence splitting
In-Reply-To: <h2khkq$159j$1@adenine.netfront.net>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<7xzlbm5ugf.fsf@ruckus.brouhaha.com>
	<08034bd0-14e5-4d67-aacf-f10988b3be43@z4g2000prh.googlegroups.com>
	<7xhbxu4del.fsf@ruckus.brouhaha.com>
	<c38e9f7a-9504-4eea-b701-279c35aa897a@l5g2000pra.googlegroups.com>
	<mailman.2539.1246596034.8015.python-list@python.org>
	<890bd597-0662-4586-979e-982de0c6f705@v23g2000pro.googlegroups.com>
	<nfi3m.2341$ze1.1151@news-server.bigpond.net.au>
	<h2khkq$159j$1@adenine.netfront.net>
Message-ID: <ern3m.2390$ze1.651@news-server.bigpond.net.au>

tsangpo wrote:
> Just a shorter implementation:
> 
> from itertools import groupby
> def split(lst, func):
>     gs = groupby(lst, func)
>     return list(gs[True]), list(gs[False])
> 

As you're replying to my post, I assume you meant a shorter
implementation my function. But it doesn't do the same thing. The idea
with my group() is similar to what Steven D'Aprano is describing in
another branch of this thread (i.e. splitting not only based on True and
False, but arbitrary groupings, e.g. 'tru', 'flash' or perhaps -1, 0, 1).

For example:
>>> def group(seq, func=bool):
...     ret = {}
...     for item in seq:
...         fitem = func(item)
...         try:
...             ret[fitem].append(item)
...         except KeyError:
...             ret[fitem] = [item]
...     return ret
...
>>> group(range(10), lambda x: x%3)
{0: [0, 3, 6, 9], 1: [1, 4, 7], 2: [2, 5, 8]}
>>> # the next one is the OP's split
>>> group(['true', '', [], [''], 'false'], bool)
{False: ['', []], True: ['true', [''], 'false']}


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 09:11:00 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 13:11:00 GMT
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <025df4fd$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 03:46:32 -0700, Klone wrote:

> Hi all. I believe in programming there is a common consensus to avoid
> code duplication, I suppose such terms like 'DRY' are meant to back this
> idea. Anyways, I'm working on a little project and I'm using TDD (still
> trying to get a hang of the process) and am trying to test the
> functionality within a method. Whoever it so happens to verify the
> output from the method I have to employ the same algorithm within the
> method to do the verification since there is no way I can determine the
> output before hand.
> 
> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

Neither -- that's essentially a pointless test. The only way to 
*correctly* test a function is to compare the result of that function to 
an *independent* test. If you test a function against itself, of course 
it will always pass:

def plus_one(x):
    """Return x plus 1."""
    return x-1  # Oops, a bug.

# Test it is correct:
assert plus_one(5) == plus_one(5)


The only general advice I can give is:

(1) Think very hard about finding an alternative algorithm to calculate 
the same result. There usually will be one.

(2) If there's not, at least come up with an alternative implementation. 
It doesn't need to be particularly efficient, because it will only be 
called for testing. A rather silly example:

def plus_one_testing(x):
    """Return x plus 1 using a different algorithm for testing."""
    if type(x) in (int, long):
        temp = 1
        for i in range(x-1):
            temp += 1
        return temp
    else:
        floating_part = x - int(x)
        return floating_part + plus_one_testing(int(x))

(The only problem is, if a test fails, you may not be sure whether it's 
because your test function is wrong or your production function.)

(3) Often you can check a few results by hand. Even if it takes you 
fifteen minutes, at least that gives you one good test. If need be, get a 
colleague to check your results.

(4) Test failure modes. It might be really hard to calculate func(arg) 
independently for all possible arguments, but if you know that func(obj) 
should fail, at least you can test that. E.g. it's hard to test whether 
or not you've downloaded the contents of a URL correctly without actually 
downloading it, but you know that http://example.com/ should fail because 
that domain doesn't exist.

(5) Test the consequences of your function rather than the exact results. 
E.g. if it's too difficult to calculate plus_one(x) independently:

assert plus_one(x) > x  # except for x = inf or -inf
assert plus_one( -plus_one(x) ) == x  # -(x+1)+1 = x

(6) While complete test coverage is the ideal you aspire to, any tests 
are better than no tests. But they have to be good tests to be useful. 
Even *one* test is better than no tests.



Hope this helps.



-- 
Steven


From lie.1296 at gmail.com  Fri Jul  3 09:16:00 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 13:16:00 GMT
Subject: stringio+tarfile
In-Reply-To: <4a4de9a8$0$1105$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<mailman.2533.1246588607.8015.python-list@python.org>
	<4a4de9a8$0$1105$4fafbaef@reader3.news.tin.it>
Message-ID: <kwn3m.2391$ze1.2254@news-server.bigpond.net.au>

superpollo wrote:
>> First problem I see is all those numbers before the lines.  That's not
>> valid python.
>>
>> Assuming that was a transcription error
> 
> not so. i intentionally add linenumbers to facilitare reference to the
> code, but if it is a nuisance i will not include them anymore.

The line numbering makes it impossible for others to copy and paste to
the interactive interpreter to see the problem code running, and makes
it hard to copy and paste into a script file. For code reference,
quoting the problematic code is usually much easier.


From ronn.ross at gmail.com  Fri Jul  3 09:26:52 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Fri, 3 Jul 2009 09:26:52 -0400
Subject: VirtualEnv
Message-ID: <9c8c445f0907030626i62d912e6k6d92247a428145e0@mail.gmail.com>

I'm attempting to write a bootstrap script for virtualenv. I just want to do
a couple of easy_install's after the environment is created. It was fairly
easy to create the script, but I can't figure out how to implement it. The
documentation was not of much help. Can someone please point me in the right
direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/08a6bbe0/attachment-0001.html>

From no.email at please.post  Fri Jul  3 09:38:20 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 13:38:20 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2l1kc$2tj$1@reader1.panix.com>

In <025db0a6$0$20657$c3e8da3 at news.astraweb.com> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:

>On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:

>> If the concern is efficiency for such cases, then simply implement
>> optional offset and length parameters for re.search(), to specify any
>> arbitrary substring to apply the search to.  To have a special-case
>> re.match() method in addition to a general re.search() method is
>> antithetical to language minimalism, and plain-old bizarre.  Maybe
>> there's a really good reason for it, but it has not been mentioned yet.

>There is, and it has.

I "misspoke" earlier.  I should have written "I'm *sure* there's
a really good reason for it."  And I think no one in this thread
(myself included, of course) has a clue of what it is.  I miss the
days when Guido still posted to comp.lang.python.  He'd know. 

Regarding the "practicality beats purity" line, it's hard to think
of a better motto for *Perl*, with all its practicality-oriented
special doodads.  (And yes, I know where the "practicality beats
purity" line comes from.)  Even *Perl* does not have a special
syntax for the task that re.match is supposedly tailor-made for,
according to the replies I've received.  Given that it is so trivial
to implement all of re.match's functionality with only one additional
optional parameter for re.search (i.e. pos), it is absurd to claim
that re.match is necessary for the sake of this special functionality.
The justification for re.match must be elsewhere.

But thanks for letting me know that I'm entitled to my opinion.
That's a huge relief.

kj



From python at mrabarnett.plus.com  Fri Jul  3 09:53:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 14:53:42 +0100
Subject: Why re.match()?
In-Reply-To: <h2l1kc$2tj$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
	<h2l1kc$2tj$1@reader1.panix.com>
Message-ID: <4A4E0D66.6070704@mrabarnett.plus.com>

kj wrote:
> In <025db0a6$0$20657$c3e8da3 at news.astraweb.com> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> 
>> On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:
> 
>>> If the concern is efficiency for such cases, then simply implement
>>> optional offset and length parameters for re.search(), to specify any
>>> arbitrary substring to apply the search to.  To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism, and plain-old bizarre.  Maybe
>>> there's a really good reason for it, but it has not been mentioned yet.
> 
>> There is, and it has.
> 
> I "misspoke" earlier.  I should have written "I'm *sure* there's
> a really good reason for it."  And I think no one in this thread
> (myself included, of course) has a clue of what it is.  I miss the
> days when Guido still posted to comp.lang.python.  He'd know. 
> 
> Regarding the "practicality beats purity" line, it's hard to think
> of a better motto for *Perl*, with all its practicality-oriented
> special doodads.  (And yes, I know where the "practicality beats
> purity" line comes from.)  Even *Perl* does not have a special
> syntax for the task that re.match is supposedly tailor-made for,
> according to the replies I've received.  Given that it is so trivial
> to implement all of re.match's functionality with only one additional
> optional parameter for re.search (i.e. pos), it is absurd to claim
> that re.match is necessary for the sake of this special functionality.
> The justification for re.match must be elsewhere.
> 
> But thanks for letting me know that I'm entitled to my opinion.
> That's a huge relief.
> 
As I wrote, re.match anchors the match whereas re.search doesn't. An
alternative would have been to implement Perl's \G anchor, but I believe
that that was invented after the re module was written.


From no.email at please.post  Fri Jul  3 10:05:08 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 14:05:08 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
Message-ID: <h2l36k$q5l$1@reader1.panix.com>



I'm will be teaching a programming class to novices, and I've run
into a clear conflict between two of the principles I'd like to
teach: code clarity vs. code reuse.  I'd love your opinion about
it.

The context is the concept of a binary search.  In one of their
homeworks, my students will have two occasions to use a binary
search.  This seemed like a perfect opportunity to illustrate the
idea of abstracting commonalities of code into a re-usable function.
So I thought that I'd code a helper function, called _binary_search,
that took five parameters: a lower limit, an upper limit, a
one-parameter function, a target value, and a tolerance (epsilon).
It returns the value of the parameter for which the value of the
passed function is within the tolerance of the target value.

This seemed straightforward enough, until I realized that, to be
useful to my students in their homework, this _binary_search function
had to handle the case in which the passed function was monotonically
decreasing in the specified interval...

The implementation is still very simple, but maybe not very clear,
particularly to programming novices (docstring omitted):

def _binary_search(lo, hi, func, target, epsilon):
    assert lo < hi
    assert epsilon > 0
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    target_plus = sense * target + epsilon
    target_minus = sense * target - epsilon
    while True:
        param = (lo + hi) * 0.5
        value = sense * func(param)
        if value > target_plus:
            hi = param
        elif value < target_minus:
            lo = param
        else:
            return param

	if lo == hi:
	    return None

My question is: is the business with sense and cmp too "clever"?

Here's the rub: the code above is more general (hence more reusable)
by virtue of this trick with the sense parameter, but it is also
a bit harder to understand.

This not an unusual situation.  I find that the processing of
abstracting out common logic often results in code that is harder
to read, at least for the uninitiated...

I'd love to know your opinions on this.

TIA!

kj



From esj at harvee.org  Fri Jul  3 10:19:10 2009
From: esj at harvee.org (Eric S. Johansson)
Date: Fri, 03 Jul 2009 10:19:10 -0400
Subject: pep 8 constants
In-Reply-To: <b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>
	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>
	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>
	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
Message-ID: <4A4E135E.5090400@harvee.org>

Horace Blegg wrote:
> I've been kinda following this. I have a cousin who is permanently wheel
> chair bound and doesn't have perfect control of her hands, but still
> manages to use a computer and interact with society. However, the
> idea/thought of disabled programmers was new to me/hadn't ever occurred
> to me.
> 
> You say that using your hands is painful, but what about your feet?
> Wouldn't it be possible to rig up some kind of foot peddle for
> shift/caps lock? Kinda like the power peddle used with sowing machines,
> so the hands are free to hold fabric.
> 
> I don't mean this in a condescending manor, and I apologize if you take
> it as such. I'm genuinely curious if you think something like this could
> work.
> 
> The way I was envisioning it working last night (and I haven't the
> faintest clue how SR works, nor have I ever used SR) was that you would
> hit the foot peddle, which would tell the SR program to capitalize the
> first letter of the next word (a smart shift, basically, so you don't
> end up doing something like ... WONderland -or- "stocks are up 1,0))%
> TOday".)
> 
> Possible? Stupid?
> 
it's not stupid.

People have used foot pedals for decades for a variety of controls. I don't
think foot pedals would work for me because when I am dictating, I pace.
Standing, sitting, I pace. With a cord headset, I'm forced to stay within about
4 feet of the computer. But what I'm using a Bluetooth headset, I will sometimes
ramble as far as 10 or 15 feet from the computer. It helps if I make the font
larger so I can glance over and see what kind of errors I've gotten.

I really love a Bluetooth headset with speech recognition. It's so liberating.

Your question about foot pedals makes me think of alternative. would it make
sense to have a handheld keyboard which would be used for command-and-control
functionality or as an adjunct to speech recognition use? It would have to be
designed in such a way that it doesn't aggravate a hand injury which may not be
possible. Anyway, just thinking out loud.



From aahz at pythoncraft.com  Fri Jul  3 10:31:36 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 07:31:36 -0700
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com> <h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
	<h2l1kc$2tj$1@reader1.panix.com>
Message-ID: <h2l4o8$sn3$1@panix3.panix.com>

In article <h2l1kc$2tj$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>In <025db0a6$0$20657$c3e8da3 at news.astraweb.com> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>>On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:
>>>
>>> If the concern is efficiency for such cases, then simply implement
>>> optional offset and length parameters for re.search(), to specify any
>>> arbitrary substring to apply the search to.  To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism, and plain-old bizarre.  Maybe
>>> there's a really good reason for it, but it has not been mentioned yet.
>>
>>There is, and it has.
>
>I "misspoke" earlier.  I should have written "I'm *sure* there's
>a really good reason for it."  And I think no one in this thread
>(myself included, of course) has a clue of what it is.  I miss the
>days when Guido still posted to comp.lang.python.  He'd know. 

You may find this enlightening:

http://www.python.org/doc/1.4/lib/node52.html
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 10:33:12 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 14:33:12 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <025e0841$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 14:05:08 +0000, kj wrote:

> ... I find that the processing of
> abstracting out common logic often results in code that is harder to
> read ...

Yes. There is often a conflict between increasing abstraction and ease of 
understanding.



[...]
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
> 
> def _binary_search(lo, hi, func, target, epsilon):
>     assert lo < hi
>     assert epsilon > 0

You're using assert for data sanitation. That is a very bad habit for you 
to be teaching novices. Your code will fail to behave as expected 
whenever the caller runs Python with the -O switch.


[...]
> My question is: is the business with sense and cmp too "clever"?

For production code? Maybe -- you would need to profile the code, and 
compare it to a less general, more simple-minded function, and see which 
performs better. If there is an excessive performance penalty, that's a 
good sign that perhaps you're being too clever, too general, or too 
abstract -- or all three.

Too clever for novices? That depends on how inexperienced they are -- are 
they new to Python or new to programming in general? Are they children or 
adults? Do they have a PhD degree or are they still at primary school? It 
depends on their experience and their intelligence -- dare I say it, some 
people will *never* get programming, let alone code-reuse. It also 
depends on how you lead up to it -- are you dropping them straight into 
the abstract code, or giving them two pieces of nearly the same code and 
showing them how to pull out the common functionality?


-- 
Steven


From bearophileHUGS at lycos.com  Fri Jul  3 10:34:23 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 3 Jul 2009 07:34:23 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
	<b0b2ff61-9023-474c-b114-863107781971@y7g2000yqa.googlegroups.com>
Message-ID: <4d99b710-45f1-42dc-b80c-1894af26db42@p29g2000yqh.googlegroups.com>

Francesco Bochicchio:
> Possibly to prepare the test data set you might need a
> different - and already proven - implementation of
> the algorithm.

Usually a brute force or slow but short algorithm is OK (beside some
hard-coded input-output pairs).

Sometimes you may use the first implementation of your code that's
usually simpler, before becoming complex because of successive
optimizations. But you have to be careful, because the first
implementation too may be buggy.

Some other times there are simpler algorithms to test if the output of
another algorithm is correct (think of exponential algorithms with a
polinomial test of the correct result), for example to test a fancy
Introsort implementation you can use a very small and simple O(n^2)
sorter, or better a simple linear loop that tests the result to be
sorted.

Here, beside unit tests, are also useful languages (or tools) that
allow to add pre- and post-conditions, class invariants, etc.

Bye,
bearophile


From alan.isaac at gmail.com  Fri Jul  3 10:34:58 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 14:34:58 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <mGo3m.591$P5.76@nwrddc02.gnilink.net>

On 7/3/2009 10:05 AM kj apparently wrote:
> The context is the concept of a binary search.  In one of their
> homeworks, my students will have two occasions to use a binary
> search.  This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.
> 
> This seemed straightforward enough, until I realized that, to be
> useful to my students in their homework, this _binary_search function
> had to handle the case in which the passed function was monotonically
> decreasing in the specified interval...
> 
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
> 
> def _binary_search(lo, hi, func, target, epsilon):
>     assert lo < hi
>     assert epsilon > 0
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
>     target_plus = sense * target + epsilon
>     target_minus = sense * target - epsilon
>     while True:
>         param = (lo + hi) * 0.5
>         value = sense * func(param)
>         if value > target_plus:
>             hi = param
>         elif value < target_minus:
>             lo = param
>         else:
>             return param
> 
> 	if lo == hi:
> 	    return None



1. Don't use assertions to test argument values!

2.
from scipy.optimize import bisect
def _binary_search(lo, hi, func, target, epsilon):
    def f(x): return func(x) - target
    return bisect(f, lo, high, xtol=epsilon)

3. If you don't want to use SciPy (why?), have them
implement http://en.wikipedia.org/wiki/Bisection_method#Pseudo-code
to produce their own `bisect` function.

hth,
Alan Isaac


From aahz at pythoncraft.com  Fri Jul  3 10:36:38 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 07:36:38 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <h2l51m$jps$1@panix3.panix.com>

In article <h2l36k$q5l$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>This seemed straightforward enough, until I realized that, to be
>useful to my students in their homework, this _binary_search function
>had to handle the case in which the passed function was monotonically
>decreasing in the specified interval...
>
>def _binary_search(lo, hi, func, target, epsilon):
>    assert lo < hi
>    assert epsilon > 0
>    sense = cmp(func(hi), func(lo))
>    if sense == 0:
>        return None
>    target_plus = sense * target + epsilon
>    target_minus = sense * target - epsilon
>    while True:
>        param = (lo + hi) * 0.5
>        value = sense * func(param)
>        if value > target_plus:
>            hi = param
>        elif value < target_minus:
>            lo = param
>        else:
>            return param
>
>	if lo == hi:
>	    return None
>
>My question is: is the business with sense and cmp too "clever"?

First of all, cmp() is gone in Python 3, unfortunately, so I'd avoid
using it.  Second, assuming I understand your code correctly, I'd change
"sense" to "direction" or "order".
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From timinganalyzer at gmail.com  Fri Jul  3 10:42:12 2009
From: timinganalyzer at gmail.com (chewie)
Date: Fri, 3 Jul 2009 07:42:12 -0700 (PDT)
Subject: The TimingAnalyzer  -- project to convert from Java to Python
Message-ID: <368b6501-5f01-4a96-9e31-274601878464@c36g2000yqn.googlegroups.com>

?Hello,

This a project related to the development of an EDA CAD tool program
called the TimingAnalyzer.  Digital engineers could use this kind of
program to analyze and document inteface timing diagrams  for IC,
ASIC, FPGA, and board level hardware projects.

The TimingAnalyzer is licensed as freeware.   I don't have the time
needed to make a high quality commercial product but I do want to keep
the development moving forward and continue to fix problems and add
new features as time permits.

www.timing-diagrams.com

Recently, I have become very interested in Python and using it to
develop similar type cad programs.  My plan is to convert the
TimingAnalyzer Java to Python with mostly a scripting interface for
building complex timing diagrams, doing timing analysis,  creating
testbenches and testvectors from waveform diagrams,
and creating timing diagrams from simulation VCD files.  Most all of
this is text based work anyway.

Developing professional GUIs is very time consuming for me.  This has
been my bottleneck with the program all along.  With a command line
interface,  you will execute a script and in one window,  and view and
edit and print the timing diagram shown in another window.   Like the
Matlab interface.

For example:

micro = m68000()
micro.write(add, data, wait_states)
micro.read(add, wait_states).

or

add_clock(......)
add_signal(.....)
add_delay(......)
add_constraint(.....)
add_or_gate(....)
add_and_gate(....)
add_counter(....)
add_clock_jitter(.....)

analyze_clock_domains(.....)
analyze_worst_case_timings(....)
analyze_best_case_timings.

read_vcd(....)
vcd_2_timing_diagram(.....)
create_testvectors(.....)
create_testbench(....)

A lot of these functions are built into the program now so its a
matter of converting them java to python.  I won't have to spend most
of the time getting the user interface to look good and be friendly.
If this is made an open source project,  I would hope that others
would help with the development and new features and bug fixes will so
progress will be made quickly.

If anyone is interested in helping with the development,  I will make
this an open source project.   Just let me know if your interested.

Thank you,
Dan Fabrizio


From bearophileHUGS at lycos.com  Fri Jul  3 10:48:57 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 3 Jul 2009 07:48:57 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <5461f308-3b3b-4baf-9ef0-c1a94d059119@y17g2000yqn.googlegroups.com>

On 3 Lug, 16:05, kj <no.em... at please.post> wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.

They are both important principles, but clarity is usually more
important because short code that can't be read can't be fixed and
modified, while long code that can be read is alive still.


> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).

Five arguments are a bit too much, even for non-novices. 2-3 arguments
are more than enough for novices.

Where are doctests'? Novices have to learn to think of tests as part
of the normal code :-)

I think the main problem in all this discussion is that generally to
learn to program you have to write code yourself, so your students
have to invent and write their own binary search. Reading your code
they are going to learn much less. Creating a binary search from
almost scratch can turn out to be too much hard for them, it means you
have to ask them to invent something simpler :-)

Programming is (among other things) problem solving, so they have to
learn to solve not easy problems from the beginning. Showing them
famous algorithms (and very good code to copy from) can be useful, but
it's less important than learning basic problem solving skills, and
much less important than learning why solving problems has to became
their purpose and pleasure :-)

Bye,
bearophile


From python at mrabarnett.plus.com  Fri Jul  3 10:52:31 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 15:52:31 +0100
Subject: pep 8 constants
In-Reply-To: <4A4E135E.5090400@harvee.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
	<4A4E135E.5090400@harvee.org>
Message-ID: <4A4E1B2F.2000700@mrabarnett.plus.com>

Eric S. Johansson wrote:
> Horace Blegg wrote:
>> I've been kinda following this. I have a cousin who is permanently wheel
>> chair bound and doesn't have perfect control of her hands, but still
>> manages to use a computer and interact with society. However, the
>> idea/thought of disabled programmers was new to me/hadn't ever occurred
>> to me.
>>
>> You say that using your hands is painful, but what about your feet?
>> Wouldn't it be possible to rig up some kind of foot peddle for
>> shift/caps lock? Kinda like the power peddle used with sowing machines,
>> so the hands are free to hold fabric.
>>
>> I don't mean this in a condescending manor, and I apologize if you take
>> it as such. I'm genuinely curious if you think something like this could
>> work.
>>
>> The way I was envisioning it working last night (and I haven't the
>> faintest clue how SR works, nor have I ever used SR) was that you would
>> hit the foot peddle, which would tell the SR program to capitalize the
>> first letter of the next word (a smart shift, basically, so you don't
>> end up doing something like ... WONderland -or- "stocks are up 1,0))%
>> TOday".)
>>
>> Possible? Stupid?
>>
> it's not stupid.
> 
> People have used foot pedals for decades for a variety of controls. I don't
> think foot pedals would work for me because when I am dictating, I pace.
> Standing, sitting, I pace. With a cord headset, I'm forced to stay within about
> 4 feet of the computer. But what I'm using a Bluetooth headset, I will sometimes
> ramble as far as 10 or 15 feet from the computer. It helps if I make the font
> larger so I can glance over and see what kind of errors I've gotten.
> 
> I really love a Bluetooth headset with speech recognition. It's so liberating.
> 
> Your question about foot pedals makes me think of alternative. would it make
> sense to have a handheld keyboard which would be used for command-and-control
> functionality or as an adjunct to speech recognition use? It would have to be
> designed in such a way that it doesn't aggravate a hand injury which may not be
> possible. Anyway, just thinking out loud.
> 
You can get giant piano keyboards that you step on, so how about a giant
computer keyboard? "I wrote 5 miles of code before lunch!" :-)


From pdmef at gmx.net  Fri Jul  3 10:54:26 2009
From: pdmef at gmx.net (Rocco Rutte)
Date: Fri, 3 Jul 2009 16:54:26 +0200
Subject: Custom CFLAGS with distutils
Message-ID: <20090703145426.GJ316@andreas.daprodeges.fqdn.th-h.de>

Hi,

I've been trying to make distutils build mercurial with custom cflags.
The only way this works is to change Makefile because I don't want to
put my changed CFLAGS into the environment and I tend to forget to run
"make" with a CFLAGS=... option.

Google brings up a special "Setup" file which should solve my problem,
but it somehow doesn't. I've tried:

    mercurial mercurial/base85.c -Xcompiler -arch x86_64
    mercurial.base85 mercurial/base85.c -Xcompiler -arch x86_64

for base85.c in the mercurial/ subdirectory. Hacking Makefile does the
trick, but having a Setup file working would never produce merge
conflicts.

What am I doing wrong?

Rocco


From metolone+gmane at gmail.com  Fri Jul  3 10:58:35 2009
From: metolone+gmane at gmail.com (Mark Tolonen)
Date: Fri, 3 Jul 2009 07:58:35 -0700
Subject: =?utf-8?Q?Re:_getting_rid_of_=E2=80=94?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com>
Message-ID: <h2l6aq$t01$1@ger.gmane.org>


"Tep" <petshmidt at googlemail.com> wrote in message 
news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
> On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> > On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
[snip]
> > > > > > how can I replace '?' sign from string? Or do split at that 
> > > > > > character?
> > > > > > Getting unicode error if I try to do it:
> >
> > > > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in 
> > > > > > position
> > > > > > 1: ordinal not in range(128)
> >
> > > > > > Thanks, Pet
> >
> > > > > > script is # -*- coding: UTF-8 -*-
[snip]
> > I just tried a bit of your code above in my interpreter here and it
> > worked fine:
> >
> > |>>> data = 'foo ? bar'
> > |>>> data.split('?')
> > |['foo ', ' bar']
> > |>>> data = u'foo ? bar'
> |>>> data.split(u'?')
> > |[u'foo ', u' bar']
> >
> > Figure out the smallest piece of "html source code" that causes the
> > problem and include that with your next post.
>
> The problem was, I've converted "html source code" to unicode object
> and didn't encoded to utf-8 back, before using split...
> Thanks for help and sorry for not so smart question
> Pet

You'd still benefit from posting some code.  You shouldn't be converting 
back to utf-8 to do a split, you should be using a Unicode string with split 
on the Unicode version of the "html source code".  Also make sure your file 
is actually saved in the encoding you declare.  I print the encoding of your 
symbol in two encodings to illustrate why I suspect this.

Below, assume "data" is your "html source code" as a Unicode string:

# -*- coding: UTF-8 -*-
data = u'foo ? bar'
print repr(u'?'.encode('utf-8'))
print repr(u'?'.encode('windows-1252'))
print data.split(u'?')
print data.split('?')


OUTPUT:

'\xe2\x80\x94'
'\x97'
[u'foo ', u' bar']
Traceback (most recent call last):
  File 
"C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", 
line 427, in ImportFile
    exec codeObj in __main__.__dict__
  File "<auto import>", line 1, in <module>
  File "x.py", line 6, in <module>
    print data.split('?')
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0: 
ordinal not in range(128)

Note that using the Unicode string in split() works.  Also note the decode 
byte in the error message when using a non-Unicode string to split the 
Unicode data.  In your original error message the decode byte that caused an 
error was 0x97, which is 'EM DASH' in Windows-1252 encoding.  Make sure to 
save your source code in the encoding you declare.  If I save the above 
script in windows-1252 encoding and change the coding line to windows-1252 I 
get the same results, but the decode byte is 0x97.

# coding: windows-1252
data = u'foo ? bar'
print repr(u'?'.encode('utf-8'))
print repr(u'?'.encode('windows-1252'))
print data.split(u'?')
print data.split('?')

'\xe2\x80\x94'
'\x97'
[u'foo ', u' bar']
Traceback (most recent call last):
  File 
"C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", 
line 427, in ImportFile
    exec codeObj in __main__.__dict__
  File "<auto import>", line 1, in <module>
  File "x.py", line 6, in <module>
    print data.split('?)
UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0: 
ordinal not in range(128)

-Mark




From nhuthuy.huynh at gmail.com  Fri Jul  3 11:18:58 2009
From: nhuthuy.huynh at gmail.com (Huynh Nhu Thuy)
Date: Fri, 3 Jul 2009 08:18:58 -0700 (PDT)
Subject: Video shows vigorous Jackson before death???
Message-ID: <333e0920-4dd9-4ab3-8e92-8dcfb207fc65@x5g2000prf.googlegroups.com>

Video shows vigorous Jackson before death???

http://hd-family.blogspot.com/2009/07/video-shows-vigorous-jackson-before.html


LOS ANGELES (AFP) ? A video released Thursday showed Michael Jackson
vigorously practicing a song-and-dance routine days before his death,
supporting accounts he had been in good health.

In footage obtained by AFP, the pop legend performed at the Staples
Center in Los Angeles on June 23, two days before he died, as he
prepared for a 50-date set in London starting in July.


http://hd-family.blogspot.com/2009/07/video-shows-vigorous-jackson-before.html


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 11:19:34 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 17:19:34 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <4a4e216e$0$7801$426a74cc@news.free.fr>

kj a ?crit :
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.  I'd love your opinion about
> it.

(snip - others already commented on this code)

> Here's the rub: the code above is more general (hence more reusable)
> by virtue of this trick with the sense parameter, but it is also
> a bit harder to understand.

Perhaps better naming (s/sense/direction/g ?) and a small comment could 
help ?

> This not an unusual situation.  I find that the processing of
> abstracting out common logic often results in code that is harder
> to read, at least for the uninitiated...

IOW : the notion of "clarity" depends on the context (including the 
reader). Anyway, there are algorithms (or implementations of...) that 
are definitly and inherently on the 'hard to read' side - well, 
complexity is something you have to learn to live with, period. The key 
is to try and make it as simple and readable *as possible*.

Also, factoring out common code - or even slightly complex code - often 
makes _client_ code (much) more readable.



From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul  3 11:22:40 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 03 Jul 2009 17:22:40 +0200
Subject: Why re.match()?
In-Reply-To: <h2i54b$eg3$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
Message-ID: <4a4e2227$0$7801$426a74cc@news.free.fr>

kj a ?crit :
(snipo
> To have a special-case
> re.match() method in addition to a general re.search() method is
> antithetical to language minimalism,

FWIW, Python has no pretention to minimalism.


From Scott.Daniels at Acm.Org  Fri Jul  3 11:43:47 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 03 Jul 2009 08:43:47 -0700
Subject: Direct interaction with subprocess - the curse of blocking I/O
In-Reply-To: <58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com>
References: <mailman.2320.1246302955.8015.python-list@python.org>
	<e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com>
	<58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com>
Message-ID: <Z-6dnZ8p8IgUuNPXnZ2dnUVZ_t-dnZ2d@pdx.net>

yam850 wrote:
> I made a python method/function for non blocking read from a file
> object....   I am happy to see comments.

OK, here's a fairly careful set of comments with a few caveats:
Does this work on windows?  The top comment should say where you
know it works.  Does this code correctly read a single line?
perhaps you need to check for a final '\n' whenever you actually
get characters, and break out there.  The rest below simply is
style-changing suggestions; take what you like and leave the rest.

> 
> def non_blocking_readline(f_read=sys.stdin, timeout_select=0.0):
>     """to readline non blocking from the file object 'f_read'
>        for 'timeout_select' see module 'select'"""
>     import select
Typically put imports at the top of the source
XXX   text_lines = ''   # empty string
Either no comment here or say _why_ it is empty.
(A)   text_lines = []  # for result accumulation
if collecting pieces (see below)
(B)   text_lines = ''  # for result accumulation
if collecting a single string

>     while True:       # as long as there are bytes to read
>         try:                              # try select
>             rlist, wlist, xlist = select.select([f_read],                                     [], [],
>                                                timeout_select)
XXX       except:                           # select ERROR
XXX           print >>sys.stderr, ("non_blocking_read select ERROR")
I'd not hide the details of the exception like that.  Don't do empty
excepts. Either don't catch it at all here, (I prefer that) or do
something like the following to capture the error:
           except Exception, why:
               print >>sys.stderr, "non_blocking_read select: %s" % why
>             break
XXX       if DEBUG: print("rlist=%s, wlist=%s, xlist=%s" % (repr(rlist),
XXX  repr(wlist), repr(xlist)))
Don't be scared of vertical space; if you must, define a function DPRINT
to ignore args; use %r to get repr
So, either:
           if DEBUG:
               print("rlist=%r, wlist=%r, xlist=%r" % (
                       rlist, wlist, xlist))
or:
elsewhere:
     def DPRINT(format_str, *args, **kwargs):
         '''Conditionally print formatted output based on DEBUG'''
         if DEBUG:
             print(format_str % (args or kwargs))
and then here:
           DPRINT("rlist=%r, wlist=%r, xlist=%r", rlist, wlist, xlist)

XXX       if  len(rlist) > 0:
Idiomatic Python: use the fact that empty containers evaluate false:
           if  rlist:
>             text_read = f_read.readline() # get a line
XXX            if DEBUG: print("after read/readline text_read:'%s', len=
> %s" % (text_read, repr(len(text_read))))
Similar comment to above:
                if DEBUG:
                    print("after read/readline text_read:%r, len=%s" % (
                                       text_read, len(text_read))
or:
                DPRINT("after read/readline text_read:%r, len=%s",
                       text_read, len(text_read))

XXX           if  len(text_read) > 0:       # there were some bytes
               if text_read:       # there were some bytes
XXX               text_lines = "".join([text_lines, text_read])
Note the join is a good idea only if you have several elements.
For a single concatenation, "=" is just fine.  The (A) case combines
at the end, the (B) case if you expect multiple concatenates are rare.
(A)               text_lines.append(text_read)
(B)               text_lines += text_read

XXX               if DEBUG: print("text_lines:'%s'" % (text_lines))
Similar to above
                if DEBUG:
                    print("text_lines:%r" % text_lines)
or:
                DPRINT("text_lines:%r", text_lines)

XXX           else:
XXX               break       # there was no byte in a line
XXX       else:
XXX           break           # there was no byte in the f_read
To make the flow of control above more clear (one case continues, others
get out), I'd also replace the above with:
                   continue # In one case we keep going
           break  # No new chars found, let's get out.

XXX   if  text_lines  ==  '':
XXX       return None
XXX   else:
XXX       return text_lines
Simplify using 'or's semantics:
(A)   return ''.join(text_lines) or None
(B)   return text_lines or None


So, with everything applied:

     import select

     def DPRINT(format_str, *args, **kwargs):
         '''Conditionally print formatted output based on DEBUG'''
         if DEBUG:
             print(format_str % (args or kwargs))

     def non_blocking_readline(f_read=sys.stdin, timeout_select=0.0):
         """to readline non blocking from the file object 'f_read'

         for 'timeout_select' see module 'select'
         """
         text_lines = ''  # for result accumulation
         while True: # as long as there are bytes to read
             rlist, wlist, xlist = select.select([f_read],   [], [], 

                                                 timeout_select)
             DPRINT("rlist=%r, wlist=%r, xlist=%r",
                       rlist, wlist, xlist)
             if rlist:
                 text_read = f_read.readline() # get a line
                 DPRINT("after read/readline text_read:%r, len=%s",
                           text_read, len(text_read))
                 if text_read:       # there were some bytes
                     text_lines += text_read
                     DPRINT("text_lines:%r", text_lines)
                     continue # Got some chars, keep going.
             break  # Nothing new found, let's get out.
        return text_lines or None


--Scott David Daniels
Scott.Daniels at Acm.Org


From jeanmichel at sequans.com  Fri Jul  3 11:58:48 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 03 Jul 2009 17:58:48 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <4A4E2AB8.6060808@sequans.com>

kj wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.  I'd love your opinion about
> it.
>   
[...]
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
My suggestion on how to improve this part for python novices:
# assuming func is monotonous
if func(high) > func(low):
    direction = 1 # aka sign of the func derivative
elif func(low) > func(high):
    direction = -1
else:
    return None

Avoid using cmp, this will prevent the "what the hell is cmp doing ?" , 
unless you want to teach your students  how to search for inline python 
documentation.
Some other list members have suggested to improve the variable naming. I 
couldn't agree more, in your case, I think clarity can be achieved as 
well with the abstraction (these notions does not necessarily collide).

Here's a link on my how-to-name bible :
http://tottinge.blogsome.com/meaningfulnames/

Jean-Michel



From kurt.alfred.mueller at gmail.com  Fri Jul  3 11:59:24 2009
From: kurt.alfred.mueller at gmail.com (yam850)
Date: Fri, 3 Jul 2009 08:59:24 -0700 (PDT)
Subject: Direct interaction with subprocess - the curse of blocking I/O
References: <mailman.2320.1246302955.8015.python-list@python.org> 
	<e7b23112-d129-4a24-aca7-43509f9712d2@d32g2000yqh.googlegroups.com> 
	<58d4c4c9-9873-499b-a9cc-1692de67893d@d32g2000yqh.googlegroups.com> 
	<Z-6dnZ8p8IgUuNPXnZ2dnUVZ_t-dnZ2d@pdx.net>
Message-ID: <8a974010-e0c8-470d-b6a8-9934cf61a377@18g2000yqa.googlegroups.com>

On 3 Jul., 17:43, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> yam850 wrote:
> > I made a python method/function for nonblockingread from a file
> > object....   I am happy to see comments.
> OK, here's a fairly careful set of comments with a few caveats:
[snip] valuable comments
> --Scott David Daniels
> Scott.Dani... at Acm.Org


Wow, thats a GREAT answer!!!
Thanks!!!
I will learn a lot while "digesting" this mail.


G
--
yam850


From lie.1296 at gmail.com  Fri Jul  3 12:10:42 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 16:10:42 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <64q3m.2408$ze1.1228@news-server.bigpond.net.au>

kj wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse.  I'd love your opinion about
> it.

Sometimes when the decision between clarity and generality becomes too
hard; you might fare better to save the code, go out for a walk to
forget the code, and start a blank text editor. Being in a fresh mind,
you may found an alternative approach, e.g.:

from __future__ import division
def binary_search(lo, hi, func, target, epsilon):
    # reverses hi and lo if monotonically decreasing
    lo, hi = (lo, hi) if func(hi) > func(lo) else (hi, lo)

    param = (lo + hi) / 2

    # loop while not precise enough
    while abs(func(param) - target) > epsilon:
        param = (lo + hi) / 2

        if target < func(param):
            hi = param
        else:
            lo = param
    return param

> The context is the concept of a binary search.  In one of their
> homeworks, my students will have two occasions to use a binary
> search.  This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.
> 
> This seemed straightforward enough, until I realized that, to be
> useful to my students in their homework, this _binary_search function
> had to handle the case in which the passed function was monotonically
> decreasing in the specified interval...
> 
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
> 
> def _binary_search(lo, hi, func, target, epsilon):
>     assert lo < hi
>     assert epsilon > 0
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
>     target_plus = sense * target + epsilon
>     target_minus = sense * target - epsilon
>     while True:
>         param = (lo + hi) * 0.5
>         value = sense * func(param)
>         if value > target_plus:
>             hi = param
>         elif value < target_minus:
>             lo = param
>         else:
>             return param
> 
> 	if lo == hi:
> 	    return None
> 
> My question is: is the business with sense and cmp too "clever"?
> 
> Here's the rub: the code above is more general (hence more reusable)
> by virtue of this trick with the sense parameter, but it is also
> a bit harder to understand.
> 
> This not an unusual situation.  I find that the processing of
> abstracting out common logic often results in code that is harder
> to read, at least for the uninitiated...
> 
> I'd love to know your opinions on this.
> 
> TIA!
> 
> kj
> 


From no.email at please.post  Fri Jul  3 12:19:22 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 16:19:22 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
Message-ID: <h2lb2a$9pt$1@reader1.panix.com>

In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:

>1. Don't use assertions to test argument values!

Out of curiosity, where does this come from? 

Thanks,

kj


From no.email at please.post  Fri Jul  3 12:20:33 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 16:20:33 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2l51m$jps$1@panix3.panix.com>
Message-ID: <h2lb4h$9pt$2@reader1.panix.com>

In <h2l51m$jps$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>First of all, cmp() is gone in Python 3, unfortunately, so I'd avoid
>using it.

Good to know.

>Second, assuming I understand your code correctly, I'd change
>"sense" to "direction" or "order".

Thanks,

kj



From petshmidt at googlemail.com  Fri Jul  3 12:24:43 2009
From: petshmidt at googlemail.com (Tep)
Date: Fri, 3 Jul 2009 09:24:43 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com> 
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com> 
	<mailman.2566.1246633128.8015.python-list@python.org>
Message-ID: <9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>

On 3 Jul., 16:58, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
> "Tep" <petshm... at googlemail.com> wrote in message
>
> news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
>
>
>
>
>
> > On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> > > On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
> [snip]
> > > > > > > how can I replace '?' sign from string? Or do split at that
> > > > > > > character?
> > > > > > > Getting unicode error if I try to do it:
>
> > > > > > > UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in
> > > > > > > position
> > > > > > > 1: ordinal not in range(128)
>
> > > > > > > Thanks, Pet
>
> > > > > > > script is # -*- coding: UTF-8 -*-
> [snip]
> > > I just tried a bit of your code above in my interpreter here and it
> > > worked fine:
>
> > > |>>> data = 'foo ? bar'
> > > |>>> data.split('?')
> > > |['foo ', ' bar']
> > > |>>> data = u'foo ? bar'
> > |>>> data.split(u'?')
> > > |[u'foo ', u' bar']
>
> > > Figure out the smallest piece of "html source code" that causes the
> > > problem and include that with your next post.
>
> > The problem was, I've converted "html source code" to unicode object
> > and didn't encoded to utf-8 back, before using split...
> > Thanks for help and sorry for not so smart question
> > Pet
>
> You'd still benefit from posting some code. ?You shouldn't be converting

I've posted code below

> back to utf-8 to do a split, you should be using a Unicode string with split
> on the Unicode version of the "html source code". ?Also make sure your file
> is actually saved in the encoding you declare. ?I print the encoding of your
> symbol in two encodings to illustrate why I suspect this.

File was indeed in windows-1252, I've changed this. For errors see
below

>
> Below, assume "data" is your "html source code" as a Unicode string:
>
> # -*- coding: UTF-8 -*-
> data = u'foo ? bar'
> print repr(u'?'.encode('utf-8'))
> print repr(u'?'.encode('windows-1252'))
> print data.split(u'?')
> print data.split('?')
>
> OUTPUT:
>
> '\xe2\x80\x94'
> '\x97'
> [u'foo ', u' bar']
> Traceback (most recent call last):
> ? File
> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> line 427, in ImportFile
> ? ? exec codeObj in __main__.__dict__
> ? File "<auto import>", line 1, in <module>
> ? File "x.py", line 6, in <module>
> ? ? print data.split('?')
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
> ordinal not in range(128)
>
> Note that using the Unicode string in split() works. ?Also note the decode
> byte in the error message when using a non-Unicode string to split the
> Unicode data. ?In your original error message the decode byte that caused an
> error was 0x97, which is 'EM DASH' in Windows-1252 encoding. ?Make sure to
> save your source code in the encoding you declare. ?If I save the above
> script in windows-1252 encoding and change the coding line to windows-1252 I
> get the same results, but the decode byte is 0x97.
>
> # coding: windows-1252
> data = u'foo ? bar'
> print repr(u'?'.encode('utf-8'))
> print repr(u'?'.encode('windows-1252'))
> print data.split(u'?')
> print data.split('?')
>
> '\xe2\x80\x94'
> '\x97'
> [u'foo ', u' bar']
> Traceback (most recent call last):
> ? File
> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> line 427, in ImportFile
> ? ? exec codeObj in __main__.__dict__
> ? File "<auto import>", line 1, in <module>
> ? File "x.py", line 6, in <module>
> ? ? print data.split('?)
> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0:
> ordinal not in range(128)
>
> -Mark

#! /usr/bin/python
# -*- coding: UTF-8 -*-
import urllib2
import re
def getTitle(input):
    title = re.search('<title>(.*?)</title>', input)
    title = title.group(1)
    print "FULL TITLE", title.encode('UTF-8')
    parts = title.split(' ? ')
    return parts[0]


def getWebPage(url):
    user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
    headers = { 'User-Agent' : user_agent }
    req = urllib2.Request(url, '', headers)
    response = urllib2.urlopen(req)
    the_page = unicode(response.read(), 'UTF-8')
    return the_page


def main():
    url = "http://bg.wikipedia.org/wiki/
%D0%91%D0%B0%D1%85%D1%80%D0%B5%D0%B9%D0%BD"
    title = getTitle(getWebPage(url))
    print title[0]


if __name__ == "__main__":
    main()


Traceback (most recent call last):
  File "C:\user\Projects\test\src\new_main.py", line 29, in <module>
    main()
  File "C:\user\Projects\test\src\new_main.py", line 24, in main
    title = getTitle(getWebPage(url))
FULL TITLE ?????????????? ??? ??????????????????
  File "C:\user\Projects\test\src\new_main.py", line 9, in getTitle
    parts = title.split(' ??? ')
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position
1: ordinal not in range(128)


From keflavich at gmail.com  Fri Jul  3 12:30:21 2009
From: keflavich at gmail.com (Keflavich)
Date: Fri, 3 Jul 2009 09:30:21 -0700 (PDT)
Subject: Compiling 64 bit python on a mac - cannot compute sizeof (int)
Message-ID: <b118d0f7-c997-4182-b734-8d39d84016d3@g7g2000prg.googlegroups.com>

I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X
10.5.7), and am running into a problem during the configure stage.

I configure with:
./configure --enable-framework=/Library/Frameworks --enable-
universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all -
with-readline-dir=/usr/local

because I want 64 and 32 bit, and I needed to install a 64 bit
readline as a prerequisite.

configure fails at:
checking size of int... configure: error: cannot compute sizeof (int)

I'm not reporting this as a bug because I know it's a problem with my
path somewhere (a friend with an identical computer but slightly
different setup was able to compile without a problem), but I don't
know what paths to change.  Any tips?

Thanks,
Adam


From no.email at please.post  Fri Jul  3 12:30:33 2009
From: no.email at please.post (kj)
Date: Fri, 3 Jul 2009 16:30:33 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com> <h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
	<h2l1kc$2tj$1@reader1.panix.com> <h2l4o8$sn3$1@panix3.panix.com>
Message-ID: <h2lbn9$9pt$3@reader1.panix.com>

In <h2l4o8$sn3$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>In article <h2l1kc$2tj$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:

>You may find this enlightening:

>http://www.python.org/doc/1.4/lib/node52.html

Indeed.  Thank you.

kj


From http  Fri Jul  3 12:33:35 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 09:33:35 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <7xk52p4tgg.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
>     sense = cmp(func(hi), func(lo))
>     if sense == 0:
>         return None
>     target_plus = sense * target + epsilon
>     target_minus = sense * target - epsilon
>     ...

The code looks confusing to me and in some sense incorrect.  Suppose
func(hi)==func(lo)==target.  In this case the solver gives up
and returns None even though it already has found a root.

Also, the stuff with the sense parameter, and target_minus and
target_plus looks messy.  I do like to use cmp.  I'd just write
something like (untested):

 def _binary_search(lo, hi, func, target, epsilon):
     y_hi, y_lo = func(hi), func(lo)
     
     while True:
         x_new = (lo + hi) * 0.5
         y_new = func(x_new)
         if abs(y_new - target) < epsilon: 
            return x_new
         elif cmp(y_new, target) == cmp(y_hi, target):
            hi = x_new
         else:
            lo = x_new
         if lo == hi:
            return None 

This uses an extra couple function calls in that trivial case, of
course.


From lie.1296 at gmail.com  Fri Jul  3 12:34:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 16:34:49 GMT
Subject: Why re.match()?
In-Reply-To: <025db0a6$0$20657$c3e8da3@news.astraweb.com>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>
	<025db0a6$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <Jqq3m.2411$ze1.1142@news-server.bigpond.net.au>

Steven D'Aprano wrote:
> On Thu, 02 Jul 2009 11:19:40 +0000, kj wrote:
> 
>> I'm sure that it is possible to find cases in which the *current*
>> implementation of re.search() would be inefficient, but that's because
>> this implementation is perverse, which, I guess, is ultimately the point
>> of my original post.  Why privilege the special case of a
>> start-of-string anchor?  
> 
> Because wanting to see if a string matches from the beginning is a very 
> important and common special case.
> 

I find the most oddest thing about re.match is that it have an implicit
beginning anchor, but not implicit end anchor. I thought it was much
more common to ensure that a string matches a certain pattern, than just
matching the beginning. But everyone's mileages vary.


From buzzard at urubu.freeserve.co.uk  Fri Jul  3 12:35:45 2009
From: buzzard at urubu.freeserve.co.uk (duncan smith)
Date: Fri, 03 Jul 2009 17:35:45 +0100
Subject: Is Psyco good for Python 2.6.1?
In-Reply-To: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
References: <30535cef-28ee-4674-999b-9d0013e72796@x3g2000yqa.googlegroups.com>
Message-ID: <h2lc13$1aeh$1@energise.enta.net>

Russ P. wrote:
> I need to speed up some Python code, and I discovered Psyco. However,
> the Psyco web page has not been updated since December 2007. Before I
> go to the trouble of installing it, does anyone know if it is still
> good for Python 2.6.1? Thanks.

If you look at http://psyco.sourceforge.net/ it would seem so (a Windows
binary for 2.6 is available).  You might want to wait a little while
because Psyco 2 is likely to be released very soon (tomorrow, the last I
heard).

Duncan


From hobesh at gmail.com  Fri Jul  3 12:53:19 2009
From: hobesh at gmail.com (Zach Hobesh)
Date: Fri, 3 Jul 2009 09:53:19 -0700
Subject: Config files with different types
In-Reply-To: <c83cde5a0907022355y706ea932w78649a17ed756809@mail.gmail.com>
References: <d4ea8a900907021056q6ec58516x3f0fddf688fd52e2@mail.gmail.com> 
	<c83cde5a0907022355y706ea932w78649a17ed756809@mail.gmail.com>
Message-ID: <d4ea8a900907030953x3a8d91d4q505337921d7d9b5e@mail.gmail.com>

yaml looks pretty interesting.  Also, I wouldn't have to change much,
I would still use the same function, and still output a dict.

Thanks!

-Zach

On Thu, Jul 2, 2009 at 11:55 PM, Javier Collado<javier.collado at gmail.com> wrote:
> Hello,
>
> Have you considered using something that is already developed?
>
> You could take a look at this presentation for an overview of what's available:
> http://us.pycon.org/2009/conference/schedule/event/5/
>
> Anyway, let me explain that, since I "discovered" it, my favourite
> format for configuration files is yaml (http://yaml.org/,
> http://pyyaml.org/). It's easy to read, easy to write, available in
> different programming languagues, etc. In addition to this, type
> conversion is already in place so I think it covers your requirement.
> For example:
>
> IIn [1]: import yaml
>
> In [2]: yaml.load("""name: person name
> ? ...: age: 25
> ? ...: is_programmer: true""")
> Out[2]: {'age': 25, 'is_programmer': True, 'name': 'person name'}
>
> Best regards,
> ? ?Javier
>
> 2009/7/2 Zach Hobesh <hobesh at gmail.com>:
>> Hi all,
>>
>> I've written a function that reads a specifically formatted text file
>> and spits out a dictionary. ?Here's an example:
>>
>> config.txt:
>>
>> Destination = C:/Destination
>> Overwrite = True
>>
>>
>> Here's my function that takes 1 argument (text file)
>>
>> the_file = open(textfile,'r')
>> linelist = the_file.read().split('\n')
>> the_file.close()
>> configs = {}
>> for line in linelist:
>> ? ? ? try:
>> ? ? ? ? ? ? ?key,value = line.split('=')
>> ? ? ? ? ? ? ?key.strip()
>> ? ? ? ? ? ? ?value.strip()
>> ? ? ? ? ? ? ?key.lower()
>> ? ? ? ? ? ? ?value.lower()
>> ? ? ? ? ? ? ?configs[key] = value
>>
>> ? ? ? except ValueError:
>> ? ? ? ? ? ? ?break
>>
>> so I call this on my config file, and then I can refer back to any
>> config in my script like this:
>>
>> shutil.move(your_file,configs['destination'])
>>
>> which I like because it's very clear and readable.
>>
>> So this works great for simple text config files. ?Here's how I want
>> to improve it:
>>
>> I want to be able to look at the value and determine what type it
>> SHOULD be. ?Right now, configs['overwrite'] = 'true' (a string) when
>> it might be more useful as a boolean. ?Is there a quick way to do
>> this? ?I'd also like to able to read '1' as an in, '1.0' as a float,
>> etc...
>>
>> I remember once I saw a script that took a string and tried int(),
>> float() wrapped in a try except, but I was wondering if there was a
>> more direct way.
>>
>> Thanks in advance,
>>
>> Zach
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>
>


From python at mrabarnett.plus.com  Fri Jul  3 12:54:10 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 17:54:10 +0100
Subject: getting rid of =?UTF-8?B?4oCU?=
In-Reply-To: <9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com>
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com>
	<mailman.2566.1246633128.8015.python-list@python.org>
	<9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>
Message-ID: <4A4E37B2.10300@mrabarnett.plus.com>

Tep wrote:
> On 3 Jul., 16:58, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
>> "Tep" <petshm... at googlemail.com> wrote in message
>>
>> news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
>>
>>
>>
>>
>>
>>> On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
>>>> On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
>> [snip]
>>>>>>>> how can I replace '?' sign from string? Or do split at that
>>>>>>>> character?
>>>>>>>> Getting unicode error if I try to do it:
>>>>>>>> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in
>>>>>>>> position
>>>>>>>> 1: ordinal not in range(128)
>>>>>>>> Thanks, Pet
>>>>>>>> script is # -*- coding: UTF-8 -*-
>> [snip]
>>>> I just tried a bit of your code above in my interpreter here and it
>>>> worked fine:
>>>> |>>> data = 'foo ? bar'
>>>> |>>> data.split('?')
>>>> |['foo ', ' bar']
>>>> |>>> data = u'foo ? bar'
>>> |>>> data.split(u'?')
>>>> |[u'foo ', u' bar']
>>>> Figure out the smallest piece of "html source code" that causes the
>>>> problem and include that with your next post.
>>> The problem was, I've converted "html source code" to unicode object
>>> and didn't encoded to utf-8 back, before using split...
>>> Thanks for help and sorry for not so smart question
>>> Pet
>> You'd still benefit from posting some code.  You shouldn't be converting
> 
> I've posted code below
> 
>> back to utf-8 to do a split, you should be using a Unicode string with split
>> on the Unicode version of the "html source code".  Also make sure your file
>> is actually saved in the encoding you declare.  I print the encoding of your
>> symbol in two encodings to illustrate why I suspect this.
> 
> File was indeed in windows-1252, I've changed this. For errors see
> below
> 
>> Below, assume "data" is your "html source code" as a Unicode string:
>>
>> # -*- coding: UTF-8 -*-
>> data = u'foo ? bar'
>> print repr(u'?'.encode('utf-8'))
>> print repr(u'?'.encode('windows-1252'))
>> print data.split(u'?')
>> print data.split('?')
>>
>> OUTPUT:
>>
>> '\xe2\x80\x94'
>> '\x97'
>> [u'foo ', u' bar']
>> Traceback (most recent call last):
>>   File
>> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
>> line 427, in ImportFile
>>     exec codeObj in __main__.__dict__
>>   File "<auto import>", line 1, in <module>
>>   File "x.py", line 6, in <module>
>>     print data.split('?')
>> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
>> ordinal not in range(128)
>>
>> Note that using the Unicode string in split() works.  Also note the decode
>> byte in the error message when using a non-Unicode string to split the
>> Unicode data.  In your original error message the decode byte that caused an
>> error was 0x97, which is 'EM DASH' in Windows-1252 encoding.  Make sure to
>> save your source code in the encoding you declare.  If I save the above
>> script in windows-1252 encoding and change the coding line to windows-1252 I
>> get the same results, but the decode byte is 0x97.
>>
>> # coding: windows-1252
>> data = u'foo ? bar'
>> print repr(u'?'.encode('utf-8'))
>> print repr(u'?'.encode('windows-1252'))
>> print data.split(u'?')
>> print data.split('?')
>>
>> '\xe2\x80\x94'
>> '\x97'
>> [u'foo ', u' bar']
>> Traceback (most recent call last):
>>   File
>> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
>> line 427, in ImportFile
>>     exec codeObj in __main__.__dict__
>>   File "<auto import>", line 1, in <module>
>>   File "x.py", line 6, in <module>
>>     print data.split('?)
>> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0:
>> ordinal not in range(128)
>>
>> -Mark
> 
> #! /usr/bin/python
> # -*- coding: UTF-8 -*-
> import urllib2
> import re
> def getTitle(input):
>     title = re.search('<title>(.*?)</title>', input)

The input is Unicode, so it's probably better for the regular expression
to also be Unicode:

     title = re.search(u'<title>(.*?)</title>', input)

(In the current implementation it actually doesn't matter.)

>     title = title.group(1)
>     print "FULL TITLE", title.encode('UTF-8')
>     parts = title.split(' ? ')

The title is Unicode, so the string with which you're splitting should
also be Unicode:

     parts = title.split(u' ? ')

>     return parts[0]
> 
> 
> def getWebPage(url):
>     user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
>     headers = { 'User-Agent' : user_agent }
>     req = urllib2.Request(url, '', headers)
>     response = urllib2.urlopen(req)
>     the_page = unicode(response.read(), 'UTF-8')
>     return the_page
> 
> 
> def main():
>     url = "http://bg.wikipedia.org/wiki/
> %D0%91%D0%B0%D1%85%D1%80%D0%B5%D0%B9%D0%BD"
>     title = getTitle(getWebPage(url))
>     print title[0]
> 
> 
> if __name__ == "__main__":
>     main()
> 
> 
> Traceback (most recent call last):
>   File "C:\user\Projects\test\src\new_main.py", line 29, in <module>
>     main()
>   File "C:\user\Projects\test\src\new_main.py", line 24, in main
>     title = getTitle(getWebPage(url))
> FULL TITLE ?????????????? ??? ??????????????????
>   File "C:\user\Projects\test\src\new_main.py", line 9, in getTitle
>     parts = title.split(' ??? ')
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position
> 1: ordinal not in range(128)


From kd at kendyck.com  Fri Jul  3 13:00:31 2009
From: kd at kendyck.com (Ken Dyck)
Date: Fri, 3 Jul 2009 10:00:31 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP: How to define API?
References: <mailman.2520.1246573083.8015.python-list@python.org>
Message-ID: <08bb0349-4bc7-448c-9ae5-49eca6d7f3ae@g7g2000prg.googlegroups.com>

On Jul 2, 6:17?pm, Allen Fowler <allen.fow... at yahoo.com> wrote:
> Since I need to work with other platforms, pickle is out... ?what are the alternatives? ?XML? JSON?

Don't forget YAML (http://yaml.org). Libraries available for Python
and .NET, among others.

-Ken


From schickb at gmail.com  Fri Jul  3 13:03:32 2009
From: schickb at gmail.com (Brad)
Date: Fri, 3 Jul 2009 10:03:32 -0700 (PDT)
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>

On Jul 3, 12:57?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> I've never needed such a split function, and I don't like the name, and
> the functionality isn't general enough. I'd prefer something which splits
> the input sequence into as many sublists as necessary, according to the
> output of the key function.

That's not a bad idea, I'll have to experiment with the alternatives.
My thought process for this, however, was that filter itself already
splits the sequence and it would have been more useful had it not
thrown away "half" of what it discovers. It could have been written to
returned two sequences with very litter perf hit for all but very
large input sequences, and been useful in more situations. What I
*really* wanted was a way to make filter itself more useful, since it
seems a bit silly to have two very similar functions.

Maybe this would be difficult to get into the core, but how about this
idea: Rename the current filter function to something like "split" or
"partition" (which I agree may be a better name) and modify it to
return the desired true and false sequences. Then recreate the
existing "filter" function with a wrapper that throws away the false
sequence.

Here are two simplified re-creations of situations where I could have
used partition (aka split):

words = ['this', 'is', 'a', 'bunch', 'of', 'words']
short, long = partition(words, lambda w: len(w) < 3)

d = {1 : 'w', 2 : 'x' ,3 : 'y' ,4 : 'z'}
keys = [1, 3, 4, 9]
found, missing = partition(keys, d.has_key)


There are probably a dozen other approaches, but the existing "filter"
is fast, clear, and *almost* good enough. So when is this useful in
general: Whenever filter itself is useful, but you want to use both
sides of the partitioning work it already does.


-Brad


From http  Fri Jul  3 13:14:00 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 10:14:00 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
Message-ID: <7xr5wx8zaf.fsf@ruckus.brouhaha.com>

Brad <schickb at gmail.com> writes:
> Maybe this would be difficult to get into the core, but how about this
> idea: Rename the current filter function to something like "split" or
> "partition" (which I agree may be a better name) and modify it to
> return the desired true and false sequences. Then recreate the
> existing "filter" function with a wrapper that throws away the false
> sequence.

This isn't so attractive, since filter takes a sequence input but
returns a list.  So if I have an iterator that produces a billion
elements of which I expect three to satisfy some predicate, then
   xs = filter(func, seq)
as currently implemented will build a 3-element list and return it.  
Under your suggestion, it would also build and throw away an (almost)
billion element list.


From lie.1296 at gmail.com  Fri Jul  3 13:27:59 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 03 Jul 2009 17:27:59 GMT
Subject: Sequence splitting
In-Reply-To: <e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
Message-ID: <zcr3m.2414$ze1.1263@news-server.bigpond.net.au>

Brad wrote:
> On Jul 3, 12:57 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>> I've never needed such a split function, and I don't like the name, and
>> the functionality isn't general enough. I'd prefer something which splits
>> the input sequence into as many sublists as necessary, according to the
>> output of the key function.
> 
> That's not a bad idea, I'll have to experiment with the alternatives.
> My thought process for this, however, was that filter itself already
> splits the sequence and it would have been more useful had it not
> thrown away "half" of what it discovers. It could have been written to
> returned two sequences with very litter perf hit for all but very
> large input sequences, and been useful in more situations. What I
> *really* wanted was a way to make filter itself more useful, since it
> seems a bit silly to have two very similar functions.

It's not that easy. filter is nearly by definition a lazy function. The
various split/group functions is impossible to be made an efficient
iterator, since they must traverse the whole list before being sure that
they have finished the group/part of the split (or even to be sure that
they have all the group keys).

> Maybe this would be difficult to get into the core, but how about this
> idea: Rename the current filter function to something like "split" or
> "partition" (which I agree may be a better name) and modify it to
> return the desired true and false sequences. Then recreate the
> existing "filter" function with a wrapper that throws away the false
> sequence.

filter has a very deep root in functional programming, I doubt it will
change any time soon. Also, consider infinite iterators. With the
"filter as wrapper to partition" scheme, it is impossible for
split/group/partition to use infinite iterator.


From fiafulli at hotmail.it  Fri Jul  3 13:39:27 2009
From: fiafulli at hotmail.it (fiafulli)
Date: Fri, 3 Jul 2009 19:39:27 +0200
Subject: PyGtkSourceView / PyScintilla
Message-ID: <4a4e41d5$0$836$4fafbaef@reader5.news.tin.it>

Hello to all.
I would have need of the recent version (possibly most recent) than one of 
the two controls in subject.
I think that wrapper for scintilla it would be better but creed that the 
development for pygtk is stopped.

therefore I'm more inclined for GtkSourceView (than today it is to the 
version 2.6.0 http://projects.gnome.org/gtksourceview/).

In the specific I need the version for windows (for that for linux I have 
not still tried but I must not have problems) of which a setup exists for 
python 2.5 but it is stop to version 2.2 
http://ftp.gnome.org/pub/gnome/binaries/win32/pygtksourceview/2.2/).

Someone would be to post the compiled in issue (if it were last version 
would be fantastic!)? or to explain step to me step as to compile it to me 
alone on windows (I have tried installing mingw, msys, autoconf, automake, 
libtools, and all the other ones of time in time, I have begun to compile 
but they are stopped to me on reference lacking pygobject 2.15 or something 
of the sort. I lost all morning!)?

The version of python that I use is the 2.5.4. on windows xp sp3 (and ubuntu 
9.04)

Thanks in advance,
Francesco

p.s.: sorry for my bad english 




From user at example.net  Fri Jul  3 13:42:39 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 19:42:39 +0200
Subject: stringio+tarfile
In-Reply-To: <h2ksj9$g38$00$1@news.t-online.com>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<4a4debb1$0$1106$4fafbaef@reader3.news.tin.it>
	<h2ksj9$g38$00$1@news.t-online.com>
Message-ID: <4a4e4311$0$47538$4fafbaef@reader1.news.tin.it>

Peter Otten wrote:

> gettarinfo() expects a real file, not a file-like object.
> You have to create your TarInfo manually.

ok... which attributes are mandatory, and which optional?


> I recommend that you have a look into the tarfile module's source code.
>

i will try... but:


$ cat /usr/lib/python2.3/tarfile.py | wc -l
1938

wow! it'll take some time ;-)


> The following seems to work:
> 
> import sys
> import time
> import tarfile
> import StringIO
> 
> sf1 = "first.txt", StringIO.StringIO("one one\n")
> sf2 = "second.txt", StringIO.StringIO("two\n")
> tf = StringIO.StringIO()
> 
> tar = tarfile.open(fileobj=tf , mode="w")
> 
> mtime = time.time()
> for name, f in [sf1 , sf2]:
>     ti = tarfile.TarInfo(name)
>     ti.size = f.len
>     ti.mtime = mtime
>     # add more attributes as needed 
>     tar.addfile(ti, f)
> 
> sys.stdout.write(tf.getvalue())
> 
> Peter
> 

much obliged mr otten

bye


From sajmikins at gmail.com  Fri Jul  3 13:44:52 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 10:44:52 -0700 (PDT)
Subject: PSP Caching
References: <mailman.2548.1246612730.8015.python-list@python.org>
Message-ID: <3e1c0979-fb6b-4d6e-80e5-a4af8d5fd96a@a36g2000yqc.googlegroups.com>

On Jul 3, 5:18?am, Johnson Mpeirwe <mjohn... at cfi.co.ug> wrote:
> Hello All,
>
> How do I stop caching of Python Server Pages (or whatever causes changes
> in a page not to be noticed in a web browser)? I am new to developing
> web applications in Python and after looking at implementations of PSP
> like Spyce (which I believed introduces new unnecessary non-PSP syntax),
> I decided to write my own PSP applications from scratch. When I modify a
> file, I keep getting the old results until I intentionally introduce an
> error (e.g parse error) and correct it after to have the changes
> noticed. There's no proxy (I am working on a windows machine unplugged
> from the network). I have Googled and no documents seem to talk about
> this. Is there any particular mod_python directive I must set in my
> Apache configuration to fix this?
>
> Any help will be highly appreciated.
>
> Johnson

I don't know much about caching with apache, but the answer mght be on
this page: http://httpd.apache.org/docs/2.2/caching.html

Meanwhile, couldn't you just send apache a restart signal when you
modify your code?

HTH,
~Simon


From Scott.Daniels at Acm.Org  Fri Jul  3 13:47:15 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 03 Jul 2009 10:47:15 -0700
Subject: Sequence splitting
In-Reply-To: <025dab69$0$20657$c3e8da3@news.astraweb.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <yM2dnX69Jo7k39PXnZ2dnUVZ_hCdnZ2d@pdx.net>

Steven D'Aprano wrote:
> I've never needed such a split function, and I don't like the name, and 
> the functionality isn't general enough. I'd prefer something which splits 
> the input sequence into as many sublists as necessary, according to the 
> output of the key function. Something like itertools.groupby(), except it 
> runs through the entire sequence and collates all the elements with 
> identical keys.
> 
> splitby(range(10), lambda n: n%3)
> => [ (0, [0, 3, 6, 9]),
>      (1, [1, 4, 7]), 
>      (2, [2, 5, 8]) ]
> 
> Your split() would be nearly equivalent to this with a key function that 
> returns a Boolean.

Well, here is my go at doing the original with iterators:

def splitter(source, test=bool):
     a, b = itertools.tee((x, test(x)) for x in source)
     return (data for data, decision in a if decision), (
	    data for data, decision in b if not decision)

This has the advantage that it can operate on infinite lists.  For
something like splitby for grouping, I seem to need to know the cases
up front:

def _make_gen(particular, src):
      return (x for x, c in src if c == particular)

def splitby(source, cases, case):
     '''Produce a dict of generators for case(el) for el in source'''
     decided = itertools.tee(((x, case(x)) for x in source), len(cases))
     return dict((c, _make_gen(c, src))
                 for c, src in zip(cases, decided))

example:

def classify(n):
     '''Least prime factor of a few'''
     for prime in [2, 3, 5, 7]:
         if n % prime == 0:
             return prime
     return 0

for k,g in splitby(range(50), (2, 3, 5, 7, 0), classify).items():
     print('%s: %s' % (k, list(g)))

0: [1, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47]
2: [0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24,
     26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48]
3: [3, 9, 15, 21, 27, 33, 39, 45]
5: [5, 25, 35]
7: [7, 49]

--Scott David Daniels
Scott.Daniels at Acm.Org


From alan.isaac at gmail.com  Fri Jul  3 13:50:23 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 17:50:23 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2lb2a$9pt$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
Message-ID: <zxr3m.613$P5.65@nwrddc02.gnilink.net>

> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:
>> 1. Don't use assertions to test argument values!


On 7/3/2009 12:19 PM kj apparently wrote:
> Out of curiosity, where does this come from? 


http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_stmt
"The current code generator emits no code for an assert statement when optimization is requested at compile time."

Alan Isaac


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 14:03:07 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 03 Jul 2009 18:03:07 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
Message-ID: <025e3974$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 16:19:22 +0000, kj wrote:

> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac
> <alan.isaac at gmail.com> writes:
> 
>>1. Don't use assertions to test argument values!
> 
> Out of curiosity, where does this come from?

Assertions are disabled when you run Python with the -O (optimise) flag. 
If you rely on assertions to verify data, then any time the user runs 
python with -O your code will be running without error checking.

assert should be used to verify program logic, not to sanitize data.


-- 
Steven


From kee at kagi.com  Fri Jul  3 14:08:19 2009
From: kee at kagi.com (Kee Nethery)
Date: Fri, 3 Jul 2009 11:08:19 -0700
Subject: Python debugger
In-Reply-To: <740981.83964.qm@web7901.mail.in.yahoo.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
Message-ID: <4A19FA5C-C135-480F-BFD1-82B7AF1500A8@kagi.com>

It's not free but I like the debugger in Komodo IDE.
Lets me simulate a web connection, lets me step through the code and  
examine the variables as it executes, can be run remotely (have not  
played with that aspect yet).
Does variable inspection of the variables so you can dive into the  
parts of arrays and dictionaries to see what the (for example) 5th  
item of the 4th item named "blah" is set to and what type of data  
element it is (int, unicode, etc). I find it tremendously useful as a  
newbie to Python.
Kee Nethery


From patrick.just4fun at gmail.com  Fri Jul  3 14:18:51 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Fri, 03 Jul 2009 20:18:51 +0200
Subject: Reversible Debugging
Message-ID: <4A4E4B8B.7090104@gmail.com>

Hello,

I am interested if there are any python modules, that supports 
reversible debugging aka stepping backwards. Any links or ideas would be 
helpful, because I am thinking of implementing something like that.

Thanks in advance,
Patrick


From petshmidt at googlemail.com  Fri Jul  3 14:34:21 2009
From: petshmidt at googlemail.com (Tep)
Date: Fri, 3 Jul 2009 11:34:21 -0700 (PDT)
Subject: =?windows-1252?Q?Re=3A_getting_rid_of_=97?=
References: <1bbf32ca-e5a0-4d03-8dbb-49d10dd0a89a@18g2000yqa.googlegroups.com><mailman.2451.1246492584.8015.python-list@python.org><02e939ad-7769-4272-80bd-bceb4b0a149d@r33g2000yqn.googlegroups.com><9594004c-7419-444d-9077-61e922468214@s9g2000yqd.googlegroups.com>
	<4416985a-b8e4-409a-b237-f0d638012524@d32g2000yqh.googlegroups.com> 
	<46d36544-1ea2-4391-8922-11b8127a2fef@o6g2000yqj.googlegroups.com> 
	<mailman.2566.1246633128.8015.python-list@python.org>
	<9f343cda-58fc-43c1-9619-4da00fa4dc57@d32g2000yqh.googlegroups.com>
	<mailman.2569.1246640050.8015.python-list@python.org>
Message-ID: <a2f5ccb7-bdb8-414d-94a0-f6eb36a328fc@26g2000yqk.googlegroups.com>

On 3 Jul., 18:54, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Tep wrote:
> > On 3 Jul., 16:58, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
> >> "Tep" <petshm... at googlemail.com> wrote in message
>
> >>news:46d36544-1ea2-4391-8922-11b8127a2fef at o6g2000yqj.googlegroups.com...
>
> >>> On 3 Jul., 06:40, Simon Forman <sajmik... at gmail.com> wrote:
> >>>> On Jul 2, 4:31 am, Tep <petshm... at googlemail.com> wrote:
> >> [snip]
> >>>>>>>> how can I replace '?' sign from string? Or do split at that
> >>>>>>>> character?
> >>>>>>>> Getting unicode error if I try to do it:
> >>>>>>>> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in
> >>>>>>>> position
> >>>>>>>> 1: ordinal not in range(128)
> >>>>>>>> Thanks, Pet
> >>>>>>>> script is # -*- coding: UTF-8 -*-
> >> [snip]
> >>>> I just tried a bit of your code above in my interpreter here and it
> >>>> worked fine:
> >>>> |>>> data = 'foo ? bar'
> >>>> |>>> data.split('?')
> >>>> |['foo ', ' bar']
> >>>> |>>> data = u'foo ? bar'
> >>> |>>> data.split(u'?')
> >>>> |[u'foo ', u' bar']
> >>>> Figure out the smallest piece of "html source code" that causes the
> >>>> problem and include that with your next post.
> >>> The problem was, I've converted "html source code" to unicode object
> >>> and didn't encoded to utf-8 back, before using split...
> >>> Thanks for help and sorry for not so smart question
> >>> Pet
> >> You'd still benefit from posting some code. ?You shouldn't be converting
>
> > I've posted code below
>
> >> back to utf-8 to do a split, you should be using a Unicode string with split
> >> on the Unicode version of the "html source code". ?Also make sure your file
> >> is actually saved in the encoding you declare. ?I print the encoding of your
> >> symbol in two encodings to illustrate why I suspect this.
>
> > File was indeed in windows-1252, I've changed this. For errors see
> > below
>
> >> Below, assume "data" is your "html source code" as a Unicode string:
>
> >> # -*- coding: UTF-8 -*-
> >> data = u'foo ? bar'
> >> print repr(u'?'.encode('utf-8'))
> >> print repr(u'?'.encode('windows-1252'))
> >> print data.split(u'?')
> >> print data.split('?')
>
> >> OUTPUT:
>
> >> '\xe2\x80\x94'
> >> '\x97'
> >> [u'foo ', u' bar']
> >> Traceback (most recent call last):
> >> ? File
> >> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> >> line 427, in ImportFile
> >> ? ? exec codeObj in __main__.__dict__
> >> ? File "<auto import>", line 1, in <module>
> >> ? File "x.py", line 6, in <module>
> >> ? ? print data.split('?')
> >> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
> >> ordinal not in range(128)
>
> >> Note that using the Unicode string in split() works. ?Also note the decode
> >> byte in the error message when using a non-Unicode string to split the
> >> Unicode data. ?In your original error message the decode byte that caused an
> >> error was 0x97, which is 'EM DASH' in Windows-1252 encoding. ?Make sure to
> >> save your source code in the encoding you declare. ?If I save the above
> >> script in windows-1252 encoding and change the coding line to windows-1252 I
> >> get the same results, but the decode byte is 0x97.
>
> >> # coding: windows-1252
> >> data = u'foo ? bar'
> >> print repr(u'?'.encode('utf-8'))
> >> print repr(u'?'.encode('windows-1252'))
> >> print data.split(u'?')
> >> print data.split('?')
>
> >> '\xe2\x80\x94'
> >> '\x97'
> >> [u'foo ', u' bar']
> >> Traceback (most recent call last):
> >> ? File
> >> "C:\dev\python\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
> >> line 427, in ImportFile
> >> ? ? exec codeObj in __main__.__dict__
> >> ? File "<auto import>", line 1, in <module>
> >> ? File "x.py", line 6, in <module>
> >> ? ? print data.split('?)
> >> UnicodeDecodeError: 'ascii' codec can't decode byte 0x97 in position 0:
> >> ordinal not in range(128)
>
> >> -Mark
>
> > #! /usr/bin/python
> > # -*- coding: UTF-8 -*-
> > import urllib2
> > import re
> > def getTitle(input):
> > ? ? title = re.search('<title>(.*?)</title>', input)
>
> The input is Unicode, so it's probably better for the regular expression
> to also be Unicode:
>
> ? ? ?title = re.search(u'<title>(.*?)</title>', input)
>
> (In the current implementation it actually doesn't matter.)
>
> > ? ? title = title.group(1)
> > ? ? print "FULL TITLE", title.encode('UTF-8')
> > ? ? parts = title.split(' ? ')
>
> The title is Unicode, so the string with which you're splitting should
> also be Unicode:
>
> ? ? ?parts = title.split(u' ? ')
>


Oh, so simple. I'm new to python and still feel uncomfortable with
unicode stuff.

Thanks to all for help!

>
>
> > ? ? return parts[0]
>
> > def getWebPage(url):
> > ? ? user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
> > ? ? headers = { 'User-Agent' : user_agent }
> > ? ? req = urllib2.Request(url, '', headers)
> > ? ? response = urllib2.urlopen(req)
> > ? ? the_page = unicode(response.read(), 'UTF-8')
> > ? ? return the_page
>
> > def main():
> > ? ? url = "http://bg.wikipedia.org/wiki/
> > %D0%91%D0%B0%D1%85%D1%80%D0%B5%D0%B9%D0%BD"
> > ? ? title = getTitle(getWebPage(url))
> > ? ? print title[0]
>
> > if __name__ == "__main__":
> > ? ? main()
>
> > Traceback (most recent call last):
> > ? File "C:\user\Projects\test\src\new_main.py", line 29, in <module>
> > ? ? main()
> > ? File "C:\user\Projects\test\src\new_main.py", line 24, in main
> > ? ? title = getTitle(getWebPage(url))
> > FULL TITLE ?????????????? ??? ?????????????????
> > ? File "C:\user\Projects\test\src\new_main.py", line 9, in getTitle
> > ? ? parts = title.split(' ??? ')
> > UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position
> > 1: ordinal not in range(128)



From charles at declareSub.com  Fri Jul  3 14:50:48 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Fri, 3 Jul 2009 14:50:48 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <025e3974$0$20657$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<025e3974$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <50230590-3F00-45ED-A1B2-DCA85366C416@declareSub.com>


On Jul 3, 2009, at 2:03 PM, Steven D'Aprano wrote:

> On Fri, 03 Jul 2009 16:19:22 +0000, kj wrote:
>
>> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac
>> <alan.isaac at gmail.com> writes:
>>
>>> 1. Don't use assertions to test argument values!
>>
>> Out of curiosity, where does this come from?
>
> Assertions are disabled when you run Python with the -O (optimise)  
> flag.
> If you rely on assertions to verify data, then any time the user runs
> python with -O your code will be running without error checking.
>
> assert should be used to verify program logic, not to sanitize data.


I wouldn't describe the use of an assert statement in the original  
code as data sanitizing, but rather as a precondition.  And with that  
description, the use of an assert statement that might be compiled  
away is not unreasonable; indeed, it certainly is so in the context of  
design by contract.

Charles Yeomans


From tjreedy at udel.edu  Fri Jul  3 14:57:20 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 14:57:20 -0400
Subject: Python 3.0 (pinin' for the fjords)
In-Reply-To: <Hue3m.534$P5.391@nwrddc02.gnilink.net>
References: <mailman.2526.1246576243.8015.python-list@python.org>
	<Hue3m.534$P5.391@nwrddc02.gnilink.net>
Message-ID: <h2lkah$4b8$1@ger.gmane.org>

Alan G Isaac wrote:
> Using the 3.1 Windows installer, I chose that I did not
> want the extensions registered, and the installer
> unregistered the .py and .pyw extensions (which I had wanted
> to keep associated with Python 2.6).
> 
> Is this intentional?

I suspect not, but Martin is the one to answer.
If you had started a new thread for this new topic
"3.1 Windows Installer trashes extension registrations"
this would have been seen more easily ;-)



From mwilson at the-wire.com  Fri Jul  3 15:08:35 2009
From: mwilson at the-wire.com (Mel)
Date: Fri, 03 Jul 2009 15:08:35 -0400
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<7x1voy5h3j.fsf@ruckus.brouhaha.com>
	<025db26e$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2lkc3$31c$1@services.telesweet.net>

Steven D'Aprano wrote:

> The most important difference between my suggestion and that of the OP is
> that he limited the key function to something which returns a truth
> value, while I'm looking for something more general which can split the
> input into an arbitrary number of collated sublists.

Generally along the lines of

def scatter (seq, criterion):
    lists = {}
    for s in seq:
        lists.setdefault (criterion (s), []).append (s)
    return lists

modulo a defaultdict or some such ?

	Mel.
> 
> 
> 




From dudeja.rajat at gmail.com  Fri Jul  3 15:10:06 2009
From: dudeja.rajat at gmail.com (dudeja.rajat at gmail.com)
Date: Sat, 4 Jul 2009 00:40:06 +0530
Subject: [Help] Python implmenentation of finding process's command line 
	parameters.
Message-ID: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>

I'm looking for some python implementation of finding the command line
parameters of a process on Windows XP SP3 machine. I found some links but
they all point me to the direction of c/c++ implememtations.

I've seen WMI, but this takes time to load. So I just though if some one has
done implementation and could pointing me in some right direction.

Regards,
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/c6b10247/attachment-0001.html>

From nosklo at gmail.com  Fri Jul  3 15:12:39 2009
From: nosklo at gmail.com (Clovis Fabricio)
Date: Fri, 3 Jul 2009 16:12:39 -0300
Subject: Python debugger
In-Reply-To: <4A19FA5C-C135-480F-BFD1-82B7AF1500A8@kagi.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
	<4A19FA5C-C135-480F-BFD1-82B7AF1500A8@kagi.com>
Message-ID: <9187a60d0907031212m7f91024m46b7d440e0815f29@mail.gmail.com>

2009/7/3 Kee Nethery <kee at kagi.com>:
> It's not free but I like the debugger in Komodo IDE.
> Lets me simulate a web connection, lets me step through the code and examine
> the variables as it executes, can be run remotely (have not played with that
> aspect yet).
> Does variable inspection of the variables so you can dive into the parts of
> arrays and dictionaries to see what the (for example) 5th item of the 4th
> item named "blah" is set to and what type of data element it is (int,
> unicode, etc). I find it tremendously useful as a newbie to Python.
> Kee Nethery

Winpdb is free and offers all those features.


From mail at timgolden.me.uk  Fri Jul  3 15:15:37 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 03 Jul 2009 20:15:37 +0100
Subject: [Help] Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
Message-ID: <4A4E58D9.6050806@timgolden.me.uk>

dudeja.rajat at gmail.com wrote:
> I'm looking for some python implementation of finding the command line
> parameters of a process on Windows XP SP3 machine. I found some links but
> they all point me to the direction of c/c++ implememtations.
> 
> I've seen WMI, but this takes time to load. So I just though if some one has
> done implementation and could pointing me in some right direction.

Someone recently posted an example using PSI [1] which seemed
quite fast.

TJG

[1] http://www.psychofx.com/psi/trac/wiki/


From mr.spoon21 at gmail.com  Fri Jul  3 15:23:20 2009
From: mr.spoon21 at gmail.com (Mr.SpOOn)
Date: Fri, 3 Jul 2009 21:23:20 +0200
Subject: Getting input the scanf way
In-Reply-To: <fcc576d0-46d7-4522-bfae-c60d53fb55fa@g1g2000yqh.googlegroups.com>
References: <mailman.2438.1246467374.8015.python-list@python.org>
	<fcc576d0-46d7-4522-bfae-c60d53fb55fa@g1g2000yqh.googlegroups.com>
Message-ID: <8f67b6f80907031223u767044ara169ddf137b5207a@mail.gmail.com>

Thanks, I think raw_input() will work just fine for my needs.


From tjreedy at udel.edu  Fri Jul  3 15:23:47 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 15:23:47 -0400
Subject: Sequence splitting
In-Reply-To: <e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<3e538aa0-e549-480d-b29b-51fa9f96b785@b15g2000yqd.googlegroups.com>
	<e83cfe0d-03ed-49c6-9f46-02a1ffc2bce8@x1g2000prh.googlegroups.com>
Message-ID: <h2lls4$aep$1@ger.gmane.org>

Brad wrote:
> On Jul 2, 8:17 pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
>> This sounds like it belongs to the python-ideas list.  I suggest
>> posting there for better feedback, since the core developers check
>> that list more often than this one.
> 
> I tried posting on python-ideas and received a "You are not allowed to
> post to this mailing list" reply. Perhaps because I am posting through
> Google groups? Or maybe one must be an approved member to post?

Spammers post thru Google groups

Either subscribe or access via news.gmane.org as gmane.comp.python.ideas.

As to your main question: this was discuss some years ago. There did not 
seem enough use cases for 'bifilter' or 'distributor' to warrent 
inclusion in the stdlib. Easy enough to do on one's own for those few 
cases. Just filter twice.

Usually, one wants to do one thing or another to each item with the 
original scan

for item in collection:
   if pred(item):
     proc_true(item)
   else:
     proc_false(item)

Having proc_true and proc_false both be append(item) is a special case.

Note that filter has been changed from returning a list to returning an 
iterator.  So a proposal for a function to return two lists would seem 
backwards. A function that returns two iterators would be possible. 
Something like itertools.tee except that each item would go on one tee 
or the other instead of both. It would have two queues (deques) instead 
of one. And it should be lazy -- items should only be pulled from the 
original iterator when an item is requested from an empty queue.

I am not sure it is worth it. In the worst case, all items are say 
'True' and you request 'False' items and all items get copied to the 
True queue before the False iterator raised StopIteration.

The way to avoid calling keyfunc(item) twice on each item is to make a 
new list first: newlist = list(map(keyfunc,iterable)). Then scan newlist 
twice.

If you write such a function, first in Python, then C, you can register 
code on PyPI and see how much interest it gets.

Terry Jan Reedy



From tjreedy at udel.edu  Fri Jul  3 15:27:25 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 15:27:25 -0400
Subject: Sequence splitting
In-Reply-To: <7xr5wx8zaf.fsf@ruckus.brouhaha.com>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<mailman.2537.1246591108.8015.python-list@python.org>	<025dab69$0$20657$c3e8da3@news.astraweb.com>	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
	<7xr5wx8zaf.fsf@ruckus.brouhaha.com>
Message-ID: <h2lm2t$aep$2@ger.gmane.org>

Paul Rubin wrote:
> Brad <schickb at gmail.com> writes:
>> Maybe this would be difficult to get into the core, but how about this
>> idea: Rename the current filter function to something like "split" or
>> "partition" (which I agree may be a better name) and modify it to
>> return the desired true and false sequences. Then recreate the
>> existing "filter" function with a wrapper that throws away the false
>> sequence.
> 
> This isn't so attractive, since filter takes a sequence input but
> returns a list. 

In modern Python (py3), it returns an iterator.



From gnewsg at gmail.com  Fri Jul  3 15:33:48 2009
From: gnewsg at gmail.com (Giampaolo Rodola')
Date: Fri, 3 Jul 2009 12:33:48 -0700 (PDT)
Subject: Python implmenentation of finding process's command line 
	parameters.
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com> 
	<mailman.2576.1246648542.8015.python-list@python.org>
Message-ID: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>

On 3 Lug, 21:15, Tim Golden <m... at timgolden.me.uk> wrote:
> dudeja.ra... at gmail.com wrote:
> > I'm looking for some python implementation of finding the command line
> > parameters of a process on Windows XP SP3 machine. I found some links but
> > they all point me to the direction of c/c++ implememtations.
>
> > I've seen WMI, but this takes time to load. So I just though if some one has
> > done implementation and could pointing me in some right direction.
>
> Someone recently posted an example using PSI [1] which seemed
> quite fast.
>
> TJG
>
> [1]http://www.psychofx.com/psi/trac/wiki/

If I'm not mistaken psi shouldn't support Windows.
You can use psutil:
http://code.google.com/p/psutil/

 >>> import psutil
 >>> p = psutil.Process(7055)
 >>> p.cmdline
 ['/usr/bin/python', '-O']
 >>>

--- Giampaolo
http://code.google.com/p/pyftpdlib
http://code.google.com/p/psutil/


From http  Fri Jul  3 15:41:20 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 12:41:20 -0700
Subject: Sequence splitting
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>
	<mailman.2537.1246591108.8015.python-list@python.org>
	<025dab69$0$20657$c3e8da3@news.astraweb.com>
	<e5836a03-629d-4b90-b23c-94773027c31c@m3g2000pri.googlegroups.com>
	<7xr5wx8zaf.fsf@ruckus.brouhaha.com>
	<mailman.2579.1246649405.8015.python-list@python.org>
Message-ID: <7xr5wximfz.fsf@ruckus.brouhaha.com>

Terry Reedy <tjreedy at udel.edu> writes:
> > This isn't so attractive, since filter takes a sequence input but
> > returns a list.
> 
> In modern Python (py3), it returns an iterator.

Still not much help in the proposed version that would return two
iterators.  


From dudeja.rajat at gmail.com  Fri Jul  3 15:41:30 2009
From: dudeja.rajat at gmail.com (dudeja.rajat at gmail.com)
Date: Sat, 4 Jul 2009 01:11:30 +0530
Subject: Python implmenentation of finding process's command line 
	parameters.
In-Reply-To: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
Message-ID: <e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com>

I have had a look at psutil, however, this only works with Python 2.6.x and
above. We are using Python 2.5.2 and updating python could pose certain
problems. So, I'm not keep on using psutils.

-- 
Regrads,
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/ab27f706/attachment-0001.html>

From mail at timgolden.me.uk  Fri Jul  3 15:48:20 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 03 Jul 2009 20:48:20 +0100
Subject: Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
Message-ID: <4A4E6084.6030001@timgolden.me.uk>

Giampaolo Rodola' wrote:
> On 3 Lug, 21:15, Tim Golden <m... at timgolden.me.uk> wrote:
>> dudeja.ra... at gmail.com wrote:
>>> I'm looking for some python implementation of finding the command line
>>> parameters of a process on Windows XP SP3 machine. I found some links but
>>> they all point me to the direction of c/c++ implememtations.
>>> I've seen WMI, but this takes time to load. So I just though if some one has
>>> done implementation and could pointing me in some right direction.
>> Someone recently posted an example using PSI [1] which seemed
>> quite fast.
>>
>> TJG
>>
>> [1]http://www.psychofx.com/psi/trac/wiki/
> 
> If I'm not mistaken psi shouldn't support Windows.
> You can use psutil:
> http://code.google.com/p/psutil/

Sorry. Exactly what I meant. (Should have checked for
the exact post rather than trusting to my memory).

TKG


From mail at timgolden.me.uk  Fri Jul  3 15:48:32 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 03 Jul 2009 20:48:32 +0100
Subject: Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
Message-ID: <4A4E6090.4060102@timgolden.me.uk>

Giampaolo Rodola' wrote:
> On 3 Lug, 21:15, Tim Golden <m... at timgolden.me.uk> wrote:
>> dudeja.ra... at gmail.com wrote:
>>> I'm looking for some python implementation of finding the command line
>>> parameters of a process on Windows XP SP3 machine. I found some links but
>>> they all point me to the direction of c/c++ implememtations.
>>> I've seen WMI, but this takes time to load. So I just though if some one has
>>> done implementation and could pointing me in some right direction.
>> Someone recently posted an example using PSI [1] which seemed
>> quite fast.
>>
>> TJG
>>
>> [1]http://www.psychofx.com/psi/trac/wiki/
> 
> If I'm not mistaken psi shouldn't support Windows.
> You can use psutil:
> http://code.google.com/p/psutil/

Sorry. Exactly what I meant. (Should have checked for
the exact post rather than trusting to my memory).

TJG


From tjgolden at gmail.com  Fri Jul  3 15:50:04 2009
From: tjgolden at gmail.com (Tim Golden)
Date: Fri, 03 Jul 2009 20:50:04 +0100
Subject: Python implmenentation of finding process's command line
	parameters.
In-Reply-To: <e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com>
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com>	<mailman.2576.1246648542.8015.python-list@python.org>	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
	<e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com>
Message-ID: <4A4E60EC.7030400@gmail.com>

dudeja.rajat at gmail.com wrote:
> I have had a look at psutil, however, this only works with Python 2.6.x and
> above. We are using Python 2.5.2 and updating python could pose certain
> problems. So, I'm not keep on using psutils.

Doesn't look as if there's anything 2.6-specific there.
Maybe the maintainer can comment, but I suspect you'd
just need to recompile and link against 2.5

TJG


From tjreedy at udel.edu  Fri Jul  3 15:51:56 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 15:51:56 -0400
Subject: pep 8 constants
In-Reply-To: <4A4E135E.5090400@harvee.org>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
	<4A4E135E.5090400@harvee.org>
Message-ID: <h2lngt$eub$1@ger.gmane.org>

Eric S. Johansson wrote:
> Horace Blegg wrote:
>> I've been kinda following this. I have a cousin who is permanently wheel
>> chair bound and doesn't have perfect control of her hands, but still
>> manages to use a computer and interact with society. However, the
>> idea/thought of disabled programmers was new to me/hadn't ever occurred
>> to me.
>>
>> You say that using your hands is painful, but what about your feet?
>> Wouldn't it be possible to rig up some kind of foot peddle for
>> shift/caps lock? Kinda like the power peddle used with sowing machines,
>> so the hands are free to hold fabric.
>>
>> I don't mean this in a condescending manor, and I apologize if you take
>> it as such. I'm genuinely curious if you think something like this could
>> work.
>>
>> The way I was envisioning it working last night (and I haven't the
>> faintest clue how SR works, nor have I ever used SR) was that you would
>> hit the foot peddle, which would tell the SR program to capitalize the
>> first letter of the next word (a smart shift, basically, so you don't
>> end up doing something like ... WONderland -or- "stocks are up 1,0))%
>> TOday".)
>>
>> Possible? Stupid?
>>
> it's not stupid.
> 
> People have used foot pedals for decades for a variety of controls. I don't
> think foot pedals would work for me because when I am dictating, I pace.
> Standing, sitting, I pace. With a cord headset, I'm forced to stay within about
> 4 feet of the computer. But what I'm using a Bluetooth headset, I will sometimes
> ramble as far as 10 or 15 feet from the computer. It helps if I make the font
> larger so I can glance over and see what kind of errors I've gotten.
> 
> I really love a Bluetooth headset with speech recognition. It's so liberating.
> 
> Your question about foot pedals makes me think of alternative. would it make
> sense to have a handheld keyboard which would be used for command-and-control
> functionality or as an adjunct to speech recognition use? It would have to be
> designed in such a way that it doesn't aggravate a hand injury which may not be
> possible. Anyway, just thinking out loud.

As long as we are thinking wildly, how about a pair of 
bluetooth-connected switches on a belt or chest band that you could 
press with your arms or elbows -- no hands involved. Sort of become a 
walking mouse ;-).

Terry




From gnewsg at gmail.com  Fri Jul  3 15:57:44 2009
From: gnewsg at gmail.com (Giampaolo Rodola')
Date: Fri, 3 Jul 2009 12:57:44 -0700 (PDT)
Subject: Python implmenentation of finding process's command line 
	parameters.
References: <e0b6c39a0907031210l3f3c4671l45c83107c519e709@mail.gmail.com> 
	<mailman.2576.1246648542.8015.python-list@python.org>
	<86554d61-9c84-4c1d-bf9f-2104d92d29ae@c36g2000yqn.googlegroups.com>
	<e0b6c39a0907031241u276800fdsa3ec24190a2cdf48@mail.gmail.com> 
	<mailman.2583.1246650608.8015.python-list@python.org>
Message-ID: <ee71ca3b-c79f-461e-9fcc-dc57ef71966a@n11g2000yqb.googlegroups.com>

On 3 Lug, 21:50, Tim Golden <tjgol... at gmail.com> wrote:

> Sorry. Exactly what I meant. (Should have checked for
> the exact post rather than trusting to my memory)

No prolem.

> dudeja.ra... at gmail.com wrote:
> > I have had a look at psutil, however, this only works with Python 2.6.x and
> > above. We are using Python 2.5.2 and updating python could pose certain
> > problems. So, I'm not keep on using psutils.
>
> Doesn't look as if there's anything 2.6-specific there.
> Maybe the maintainer can comment, but I suspect you'd
> just need to recompile and link against 2.5
>
> TJG

psutil works on Python 2.4, 2.5 and 2.6.
If you are on Windows, you can get the precompiled binary for Python
2.5 from here:
http://code.google.com/p/psutil/downloads/list


--- Giampaolo
http://code.google.com/p/pyftpdlib
http://code.google.com/p/psutil/


From sajmikins at gmail.com  Fri Jul  3 16:04:21 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 13:04:21 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<Xns9C3CBEAA880F8duncanbooth@127.0.0.1>
	<gY2dnYcC25IBktDXnZ2dnUVZ_hqdnZ2d@pdx.net> 
	<529c44a7-eb97-4d56-a376-1152cb9eaea2@37g2000yqp.googlegroups.com> 
	<vgh3m.2329$ze1.1542@news-server.bigpond.net.au>
Message-ID: <c6c65f65-3279-42b9-b349-340a15ad6e65@y7g2000yqa.googlegroups.com>

On Jul 3, 2:09?am, Lie Ryan <lie.1... at gmail.com> wrote:
> Simon Forman wrote:
> > On Jul 2, 3:57 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> >> Duncan Booth wrote:
> >>> Simon Forman <sajmik... at gmail.com> wrote:
> >>>> ...
> >>>> if self.higher is self.lower is None: return
> >>>> ...
> >>> As a matter of style however I wouldn't use the shorthand to run two 'is'
> >>> comparisons together, I'd write that out in full if it was actually needed
> >>> here.
> >> Speaking only to the style issue, when I've wanted to do something like
> >> that, I find:
>
> >> ? ? ? ?if self.higher is None is self.lower:
> >> ? ? ? ? ? ?...
>
> >> more readable, by making clear they are both being compared to a
> >> constant, rather than compared to each other.
>
> > I was going to do it that way for aesthetics if nothing else, but in
> > this particular code "self.higher is self.lower" could only have been
> > True if they were both None, so the final "is None" was redundant and
> > I only included it as a "just-in-case" check in case someone someday
> > used the code in such a way as to assign the same object (not None) to
> > both self.higher and self.lower... ?Totally pointless, I'm sorry to
> > say. ?I'm glad the whole line was redundant really.
>
> I say, you should keep the `is None` for readability and to safe guard
> against immutable optimization and/or Singleton objects. Due to an
> implementation detail, python does not guarantee that two immutable
> object will return different objects; you have:
>
> >>> a = 1
> >>> b = 1
> >>> a is b
>
> True

I probably would have kept the 'is None' for those reasons except that
this code was never meant to be used by anyone but me, and it turned
out the entire line was redundant anyway. :]


From python at mrabarnett.plus.com  Fri Jul  3 16:07:50 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 03 Jul 2009 21:07:50 +0100
Subject: Sequence splitting
In-Reply-To: <h2lkc3$31c$1@services.telesweet.net>
References: <6b9702ab-2eb6-4348-b298-5f53012682be@q40g2000prh.googlegroups.com>	<mailman.2537.1246591108.8015.python-list@python.org>	<025dab69$0$20657$c3e8da3@news.astraweb.com>	<7x1voy5h3j.fsf@ruckus.brouhaha.com>	<025db26e$0$20657$c3e8da3@news.astraweb.com>
	<h2lkc3$31c$1@services.telesweet.net>
Message-ID: <4A4E6516.8090207@mrabarnett.plus.com>

Mel wrote:
> Steven D'Aprano wrote:
> 
>> The most important difference between my suggestion and that of the OP is
>> that he limited the key function to something which returns a truth
>> value, while I'm looking for something more general which can split the
>> input into an arbitrary number of collated sublists.
> 
> Generally along the lines of
> 
> def scatter (seq, criterion):
>     lists = {}
>     for s in seq:
>         lists.setdefault (criterion (s), []).append (s)
>     return lists
> 
> modulo a defaultdict or some such ?
> 
Somehow this reminds me of the new Counter class, except that it's
making lists instead of counts.


From user at example.net  Fri Jul  3 16:14:22 2009
From: user at example.net (superpollo)
Date: Fri, 03 Jul 2009 22:14:22 +0200
Subject: stringio+tarfile (or better... zipfile)
In-Reply-To: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <4a4e66a0$0$1115$4fafbaef@reader4.news.tin.it>

following the excellent suggestions received, i tried to adapt the 
problem to zipfile, and i wrote this:

$ cat zip001.py
import sys
import zipfile
import StringIO

nb1 = "first.txt", StringIO.StringIO("one one\n")
nb2 = "second.txt", StringIO.StringIO("two\n")
zb = StringIO.StringIO()

zip = zipfile.ZipFile(zb , "w" , zipfile.ZIP_DEFLATED)

for name , buffer in [nb1 , nb2]:
     zip.writestr(name, buffer.getvalue()*1000)
zip.close()

sys.stdout.write(zb.getvalue())
$ python zip001.py > zip001.out
$ unzip -l zip001.out
Archive:  zip001.out
   Length     Date   Time    Name
  --------    ----   ----    ----
      8000  07-03-09 22:07   first.txt
      4000  07-03-09 22:07   second.txt
  --------                   -------
     12000                   2 files
$

it seems to me thaz zipfile has a simpler usability... any comments?

thanks again and bye bye


From sajmikins at gmail.com  Fri Jul  3 16:17:16 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 13:17:16 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
Message-ID: <2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>

On Jul 3, 12:56?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> writes:
> > > Yes, but the concept of null pointers is considered kludgy these days.
> > Seriously? "kludgy"? ?(I really AM getting old.)
>
> ?http://math.andrej.com/2009/04/11/on-programming-language-design/
>
> discusses the issue (scroll down to "Undefined values" section).

Hmm, I'm not convinced.  I read that post with interest, but his
argument against None et. al. was just this:

"...stick to the principle: NULL is wrong because it causes horrible
and tricky mistakes which appear even after the program was tested
thoroughly. You cannot introduce NULL into the language and tell the
programmer to be careful about it. The programmer is not capable of
being careful!"

To me that seems weak and too general, you could say /anything/
"...causes horrible and tricky mistakes which appear even after the
program was tested thoroughly."

He does go on to say, in a reply to a comment, "In my opinion, at the
end of the day the quality of the code depends more on the quality of
its author than on the quality of the language he uses. But this does
not mean that the quality of the programming language does not
matter."

Which I agree with wholeheartedly.  I just don't see that he made a
strong case that the inclusion of NULLs directly implies poor quality
of language.

(I like Haskell's Maybe, but saying A is better than B doesn't imply
that B is therefore terrible.)



> > Well I wouldn't know, I've been fortunate enough to program mostly in
> > python for over half a decade now and None and 0 are as close as I've
> > gotten to NULL in a long time.
>
> Right, and how many times have you had to debug
>
> ? ?AttributeError: 'NoneType' object has no attribute 'foo'
>
> or the equivalent null pointer exceptions in Java, C, or whatever?
> They are very common. ?And the basic idea is that if you avoid using
> null pointers in the first place, you'll get fewer accidental null
> pointer exceptions.

I have encountered exceptions like that, but usually as a result of
e.g. omitting a return statement (so the caller gets None instead of
whatever should have been returned.)

I don't usually write "pointer" style code in python. In fact, other
than this BTree and the Dancing Links algorithm I mentioned earlier I
can't recall ever having done it.  Indeed, python's omission of
pointers is one of the reasons I'm so fond of it.

In my experience with python exceptions like that one are indicators
of something bad wrong with my code, not of misuse of None (as NULL
pointer.)



> > That sounds very interesting, but I'm only writing a BTree to then use
> > it to play with "persistent data structures"
>
> But you have implemented a mutable tree. ?If you want to write a
> persistent one, then write a persistent one! ?You also use a wishful

The paper I'm working from is about general techniques for making
persistent data structures from mutable forms, thus I wanted a mutable
BTree to then "overwrite" with a persistent form.


> heuristic in the hope of keeping the tree balanced--if you want a
> balanced tree, why not use one that's guaranteed to stay in balance?
> AVL trees are pretty easy to implement; maybe you could try writing a
> persistent one:
>
> ?http://en.wikipedia.org/wiki/AVL_tree

The balance (or lack thereof) of the tree is not important (in this
use.) I threw in that heuristic in the delete function because it was
easy enough and it was mentioned in the wikipedia article on BTrees.
AVL trees are easy too, but still more complicated than I need.


> > In this particular case it's somewhat more elegant (IMO) to check "is
> > None".
>
> Well, I can't understand why that might be, but it's surely
> subjective, so ok.

It's a matter of this:

if a is None:
    return b
if b is None:
    return a
# handle both non-None here...

vs. this:

if a is not None:
    if b is not None:
        # handle both non-None here...
    else:
        return a
return b

Everything is subjective, but I think the first one is more elegant
IMO.



> > > I'm sorry but I find that class rather ugly. ?The code would be a lot
> > > smaller and have fewer corner cases with a different data representation.
>
> > Um, thanks? ?Seriously though, care to put your money where your mouth
> > is? I'd be interested to see a BTree implemented as you indicated above.
>
> Er, I'm not trying to argue with you. ?You asked for people's advice
> and impressions, so I gave you some. ?I don't feel like rewriting that

I know, I asked for it. :] But it still stings a little to hear
someone call my code "rather ugly".  No hard feelings. I'm not trying
to argue with you either. :]


> whole class, but I'll do a method or two, using [] to represent an
> empty node. ?(Hmm, actually changing the empty node representation did
> less to shorten the code than just getting rid of a bunch of
> duplication. ?Really, I'd tend to look for a slightly different tree
> structure which tried to avoid these issues).

Hmm, I really don't see that using an empty list rather than None as a
stand-in for NULL pointer bought you anything there.  In fact, this
code would work identically if you replaced [] with None.

I was hoping to see some clever code-fu involving list manipulation or
something.  When would you ever store a value in the empty list
"nodes" anyway?

> Untested:
>
> class BinaryTree:
> ? ? def __init__(self, key, value):
> ? ? ? ? self.key = key
> ? ? ? ? self.value = value
> ? ? ? ? self.higher = self.lower = []
>
> ? ? def get(self, key):
> ? ? ? ? if key == self.key:
> ? ? ? ? ? ? return self.value
> ? ? ? ? branch = self.lower if key < self.key else self.higher
> ? ? ? ? return branch.get(key) if branch else []
>
> ? ? def insert(self, key, value):
> ? ? ? ? def xinsert(xtree): ?# xtree is either a tree or []
> ? ? ? ? ? ?if not xtree: xtree = BinaryTree(key, value)
> ? ? ? ? ? ?else: xtree.insert(key, value)
> ? ? ? ? ? ?return xtree
>
> ? ? ? ? if key == self.key:
> ? ? ? ? ? ? self.value = value
> ? ? ? ? elif key < self.key:
> ? ? ? ? ? ? self.lower = xinsert(self.lower)
> ? ? ? ? else:
> ? ? ? ? ? ? self.higher = xinsert(self.higher)
>
> and so forth.



From dickinsm at gmail.com  Fri Jul  3 16:18:09 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Fri, 3 Jul 2009 13:18:09 -0700 (PDT)
Subject: Compiling 64 bit python on a mac - cannot compute sizeof (int)
References: <b118d0f7-c997-4182-b734-8d39d84016d3@g7g2000prg.googlegroups.com>
Message-ID: <6c0287d8-c9f5-44e2-8159-fe5c88494a62@g1g2000yqh.googlegroups.com>

On Jul 3, 5:30?pm, Keflavich <keflav... at gmail.com> wrote:
> I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X
> 10.5.7), and am running into a problem during the configure stage.
>
> I configure with:
> ./configure --enable-framework=/Library/Frameworks --enable-
> universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all -
> with-readline-dir=/usr/local
>
> because I want 64 and 32 bit, and I needed to install a 64 bit
> readline as a prerequisite.
>
> configure fails at:
> checking size of int... configure: error: cannot compute sizeof (int)

I confess that I don't fully understand the intricacies of the various
OS X autoconf options, but I think the problem is that the --enable-
universalsdk option takes a directory.  If that directory isn't
given, it appears to default to /Developer/SDKs/MacOSX10.4u.sdk (at
least on my OS X 10.5.7 machine), which would likely conflict with
your MACOSX_DEPLOYMENT_TARGET=10.5 setting.

Try either changing MACOSX_DEPLOYMENT_TARGET to 10.4, or using --
enable-universalsdk=/Developer/SDKs/MacOSX10.5.sdk  (or whatever the
appropriate directory is on your system).  For some reason, I think
using --enable-universalsdk=/ also works on my system.  If none of
that helps, you might try asking this question over on the pythonmac-
sig mailing list. (http://mail.python.org/mailman/listinfo/pythonmac-
sig)

Mark


From timr at probo.com  Fri Jul  3 16:20:18 2009
From: timr at probo.com (Tim Roberts)
Date: Fri, 03 Jul 2009 13:20:18 -0700
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<4A4CA278.4050604@ieee.org> <h2i84f$v2t$1@ger.gmane.org>
	<mailman.2491.1246540910.8015.python-list@python.org>
Message-ID: <ftps459nklqio3nghaaraniqo3fs9r8ck8@4ax.com>

Dave Angel <davea at dejaviewphoto.com> wrote:
>   
>You're right of course.  What I was trying to say was it deletes the 
>reference to the object.  Unlike obj = None, del obj removes the 
>reference (attribute) entirely. Although I don't know what it should be 
>called if it's a local variable.  Perhaps it "unbinds" the name.

Yes.  As far as the object is concerned, "obj = None" and "del obj" are
exactly identical.  In both cases, there is one less binding to the name.

The difference between the two is only whether the name lives on in the
namespace.

A local variable is (usually) just a name in the local() namespace.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From tjreedy at udel.edu  Fri Jul  3 16:36:50 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 03 Jul 2009 16:36:50 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <025e3974$0$20657$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<025e3974$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2lq52$lp0$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 03 Jul 2009 16:19:22 +0000, kj wrote:
> 
>> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac
>> <alan.isaac at gmail.com> writes:
>>
>>> 1. Don't use assertions to test argument values!
>> Out of curiosity, where does this come from?
> 
> Assertions are disabled when you run Python with the -O (optimise) flag. 
> If you rely on assertions to verify data, then any time the user runs 
> python with -O your code will be running without error checking.
> 
> assert should be used to verify program logic, not to sanitize data.

In other words, assertions should never happen, whereas your assertions 
could easily happen with 'bad' input. An example of program logic 
assertion would be 'assert <loop-invariant>' at the top of the loop. 
That would be useful for development, but would not be needed for 
production use of tested code.

tjr




From sajmikins at gmail.com  Fri Jul  3 16:46:28 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Fri, 3 Jul 2009 13:46:28 -0700 (PDT)
Subject: Python debugger
References: <mailman.2555.1246623750.8015.python-list@python.org>
Message-ID: <ae885a04-6626-46e9-9480-5d7a8ce47218@h11g2000yqb.googlegroups.com>

On Jul 3, 8:15?am, srinivasan srinivas <sri_anna... at yahoo.co.in>
wrote:
> Hi,
> Could you suggest some python debuggers?
>
> Thanks,
> Srini
>
> ? ? ? Love Cricket? Check out live scores, photos, video highlights and more. Click herehttp://cricket.yahoo.com

Ipython has good debugger integration.


From http  Fri Jul  3 16:50:12 2009
From: http (Paul Rubin)
Date: 03 Jul 2009 13:50:12 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
Message-ID: <7xhbxtjxtn.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> "...stick to the principle: NULL is wrong because it causes horrible
> and tricky mistakes which appear even after the program was tested
> thoroughly. You cannot introduce NULL into the language and tell the
> programmer to be careful about it. The programmer is not capable of
> being careful!"
> 
> To me that seems weak and too general, you could say /anything/
> "...causes horrible and tricky mistakes which appear even after the
> program was tested thoroughly."

On the contrary, general means powerful :).  For example, you can say
that malloc/free in C causes horrible and tricky mistakes etc.  Python
avoids the mistakes by having automatic storage management.

> Which I agree with wholeheartedly.  I just don't see that he made a
> strong case that the inclusion of NULLs directly implies poor quality
> of language.
> 
> (I like Haskell's Maybe, but saying A is better than B doesn't imply
> that B is therefore terrible.)

I wouldn't say Python's None is terrible, but the programming style in
which None is used as a marker for "absent value" is genuinely a
source of bugs, requiring care when used.  Often it's easy to just
avoid it and all the bugs that come with it.

Haskell's Maybe type, ML's Option type, and various similar constructs
in other recently designed languages all are responses to the
shortcomings of None-like constructs in older languages.  I'm not
going purely by that one guy's blog post, though I do think that post
was pretty good.

> Hmm, I really don't see that using an empty list rather than None as a
> stand-in for NULL pointer bought you anything there.  In fact, this
> code would work identically if you replaced [] with None.

Yes I noticed that too (and mentioned it) after writing the code.  I
think the real problem is that the class has unnatural semantics and
Python's OOP system (well, OOP in general) is also sort of kludgy.
I will think about a possible rewrite.


From keflavich at gmail.com  Fri Jul  3 19:01:42 2009
From: keflavich at gmail.com (Adam)
Date: Fri, 3 Jul 2009 16:01:42 -0700 (PDT)
Subject: Compiling 64 bit python on a mac - cannot compute sizeof (int)
References: <b118d0f7-c997-4182-b734-8d39d84016d3@g7g2000prg.googlegroups.com>
	<6c0287d8-c9f5-44e2-8159-fe5c88494a62@g1g2000yqh.googlegroups.com>
Message-ID: <73186719-e5a6-4661-a06c-cf6f2570996b@2g2000prl.googlegroups.com>

On Jul 3, 2:18?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 3, 5:30?pm, Keflavich <keflav... at gmail.com> wrote:
>
> > I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X
> > 10.5.7), and am running into a problem during the configure stage.
>
> > I configure with:
> > ./configure --enable-framework=/Library/Frameworks --enable-
> > universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all -
> > with-readline-dir=/usr/local
>
> > because I want 64 and 32 bit, and I needed to install a 64 bit
> > readline as a prerequisite.
>
> > configure fails at:
> > checking size of int... configure: error: cannot compute sizeof (int)
>
> I confess that I don't fully understand the intricacies of the various
> OS X autoconf options, but I think the problem is that the --enable-
> universalsdk option takes a directory. ?If that directory isn't
> given, it appears to default to /Developer/SDKs/MacOSX10.4u.sdk (at
> least on my OS X 10.5.7 machine), which would likely conflict with
> your MACOSX_DEPLOYMENT_TARGET=10.5 setting.
>
> Try either changing MACOSX_DEPLOYMENT_TARGET to 10.4, or using --
> enable-universalsdk=/Developer/SDKs/MacOSX10.5.sdk ?(or whatever the
> appropriate directory is on your system). ?For some reason, I think
> using --enable-universalsdk=/ also works on my system. ?If none of
> that helps, you might try asking this question over on the pythonmac-
> sig mailing list. (http://mail.python.org/mailman/listinfo/pythonmac-
> sig)
>
> Mark

Thanks.  I also determined after the fact that universalsdk was the
problem, but I didn't know how to fix it.  Unfortunately, it turns out
what you identified was a transcription error on my part - I had been
using --enable-universalsdk instead of --enable-universalsdk=/.
Thanks for the help, I appreciate it!

Adam


From alan.isaac at gmail.com  Fri Jul  3 19:18:15 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 03 Jul 2009 23:18:15 GMT
Subject: 3.1 Windows Installer trashes extension registrations
In-Reply-To: <mailman.2573.1246647459.8015.python-list@python.org>
References: <mailman.2526.1246576243.8015.python-list@python.org>	<Hue3m.534$P5.391@nwrddc02.gnilink.net>
	<mailman.2573.1246647459.8015.python-list@python.org>
Message-ID: <Xkw3m.688$P5.676@nwrddc02.gnilink.net>

> Alan G Isaac wrote:
>> Using the 3.1 Windows installer, I chose that I did not 
>> want the extensions registered, and the installer 
>> unregistered the .py and .pyw extensions (which I had 
>> wanted to keep associated with Python 2.6).
>> Is this intentional?


On 7/3/2009 2:57 PM Terry Reedy apparently wrote:
> I suspect not, but Martin is the one to answer. 
> If you had started a new thread for this new topic 
> "3.1 Windows Installer trashes extension registrations"
> this would have been seen more easily ;-)


Done.

Cheers,
Alan Isaac


From gallium.arsenide at gmail.com  Fri Jul  3 19:26:39 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Fri, 3 Jul 2009 16:26:39 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
Message-ID: <9d99c5ca-f497-473f-a22f-a5219597bcd7@h11g2000yqb.googlegroups.com>

On Jul 3, 4:50?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> I wouldn't say Python's None is terrible, but the
> programming style in which None is used as a marker
> for "absent value" is genuinely a source of bugs,
> requiring care when used. ?Often it's easy to just
> avoid it and all the bugs that come with it.

While other languages may make it easier to avoid these types of bugs,
I think it's pretty natural to use Python's None as a marker for
"absent value", if you're coding in Python.  Python seems to encourage
this by having functions return None when there is no explicit return
value, and by having the interactive command line print nothing at all
when the expression evaluates to None.

I won't argue with anyone who wants to call these design flaws, but it
seems to me that using None this way in one's own Python code is
reasonably Pythonic.

John


From tn.pablo at gmail.com  Fri Jul  3 19:40:03 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Fri, 3 Jul 2009 18:40:03 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <fdd00b510907031640y3b98604fo3c26dc8695ed8fef@mail.gmail.com>

On Fri, Jul 3, 2009 at 09:05, kj<no.email at please.post> wrote:
> The context is the concept of a binary search. ?In one of their
> homeworks, my students will have two occasions to use a binary
> search. ?This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.

Five params for a novice function is overkill.  I'd drop the epsilon
thing and, assuming you are searching in a list, tuple or something
similar, make the lower limit default to the first index and the upper
default to the last one.

In fact, I'd let them to realize that a function is convenient, and
base some of the grading in whether they wrote it or not.  Just a
thought.

-- 
Pablo Torres N.


From ldo at geek-central.gen.new_zealand  Fri Jul  3 20:08:17 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sat, 04 Jul 2009 12:08:17 +1200
Subject: Idioms and Anti-Idioms Question
References: <mailman.1932.1245644100.8015.python-list@python.org>
	<H0F%l.20231$y61.5030@news-server.bigpond.net.au>
	<slrnh402pc.deb.peter@box8.pjb.com.au>
	<mailman.2018.1245772229.8015.python-list@python.org>
	<h2erl2$h7l$1@lust.ihug.co.nz>
	<mailman.2493.1246544869.8015.python-list@python.org>
Message-ID: <h2m6hi$q81$1@lust.ihug.co.nz>

In message <mailman.2493.1246544869.8015.python-list at python.org>, J. Cliff 
Dyer wrote:

> On Wed, 2009-07-01 at 17:19 +1200, Lawrence D'Oliveiro wrote:
>>
>> In message <mailman.2018.1245772229.8015.python-list at python.org>, J.
>> Cliff Dyer wrote:
>> 
>> > If the lines got separated, a leading + could disappear into its line
>> > without any errors showing up.  A trailing + would raise a syntax
>> > error.
>> 
>> Unless, of course, it was moved onto the previous line as part of
>> whatever caused the separation of the lines. How would you guard against
>> that?
> 
> Can you give an example of what you mean?

Sure. Just start with an example of what you mean.



From asm198 at gmail.com  Fri Jul  3 21:14:23 2009
From: asm198 at gmail.com (Icarus)
Date: Fri, 3 Jul 2009 18:14:23 -0700 (PDT)
Subject: Problems with using queue in Tkinter application
Message-ID: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>

I'm working on a serial protocol analyzer in python.  We have an
application written by someone else in MFC but we need something that
is cross platform.  I intended to implement the GUI portion in Tkinter
but am having trouble.

The idea is that I will read messages from the serial port and output
them to a Tkinter Text object initially.  Eventually it will have
other functionality but that's it for the short term.  I've written
this little test app to experiment with putting things on the GUI via
a Queue which is polled by the Tkinter loop.

On some machines this code works fine and I get whatever I type in
displayed in the Text widget.  On others I get errors like this as
soon as I start it running.

error in background error handler:
out of stack space (infinite loop?)
    while executing
"::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
    while execu..."


I don't understand why on some machines it works exactly as expected
and on others it acts the same way Tkinter does when I call functions
directly from outside the Tkinter thread.  Does anyone have any
suggestions?  The full code as appended below.  Thanks in advance.

[code]

import Queue

class functionQueue:

    def __init__(self, root = None, timeout = 250):

        self.functionQueue = Queue.Queue()
        self.root = root
        self.timeout = timeout

        if(self.root):
            self.pop_function(root)


    def pop_function(self, root = None):

        try:
            funcArgList = self.functionQueue.get(block = False)
        except Queue.Empty:
            pass
        else:
            try:
                funcArgList[0](*funcArgList[1])
            except:
                try:
                    print "Failed to call function", funcArgList[0]
                except:
                    print "Failed to call function"

        if(root):
            root.after(self.timeout, lambda: self.pop_function
(self.root))

    def add_function(self, function, argList):

        try:
            self.functionQueue.put([function, argList])
        except:
            pass


if( __name__ == '__main__'):

    import Tkinter
    import thread

    text = Tkinter.Text()
    text.pack()

    myQueue = functionQueue(text, 50)

    def gui_loop():
        try:
            text.mainloop()
        except:
            import os
            os._exit(1)

    thread.start_new_thread(text.mainloop, ())

    while(True):
        usrInput = raw_input()

        if(usrInput == "-1"):
            import os
            os._exit(0)

        myQueue.add_function(text.insert, ['end', usrInput + "\n"])
        myQueue.add_function(text.see, ['end'])

[/code]



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul  3 22:04:42 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 02:04:42 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
Message-ID: <025eaa4f$0$20657$c3e8da3@news.astraweb.com>

On Fri, 03 Jul 2009 13:50:12 -0700, Paul Rubin wrote:

> I wouldn't say Python's None is terrible, but the programming style in
> which None is used as a marker for "absent value" is genuinely a source
> of bugs, requiring care when used.  Often it's easy to just avoid it and
> all the bugs that come with it.

So you keep saying, but I don't believe it. I've never found this to be a 
problem in my own code: a few silly mistakes where I accidentally assign 
the result of a function that operates by side-effect:

blist = alist.sort()

or similar, and I haven't done that for years now.

No, wait, I tell I lie... re.search() sometimes bites me, because 
sometimes it returns None and sometimes it returns a matchobject and I 
don't use re often enough to have good habits with it yet. But that's a 
good example of why removing NULL (None, nul, nil, whatever you want to 
call it) doesn't lower the number of bugs, it just changes their nature: 
if re.search didn't return None, I'd still have trouble with it.

There are three natural approaches to (say) re.search() for dealing with 
failure:

(1) return a sentinel value like None;

(2) return a matchobject which tests False;

(3) raise an exception.

Here's how you would use them correctly:


# 1 or 2 are handled identically
o = re.search(s)
if o:
    process_match(o)
else:
    print "Not found"


# 3 is different
try:
    process_match(re.search(s))
except Exception:
    print "Not found"


There's essentially little or no difference in the handling. In all three 
cases, if you assume search will always succeed or forget to handle the 
failure case, you will write incorrect code:

process_match(re.search(s))

and get an unexpected exception. The only difference is that the specific 
exception will differ between the cases. Remove None from the scenario 
doesn't reduce the number of bugs, it just changes their nature.



-- 
Steven


From gagsl-py2 at yahoo.com.ar  Fri Jul  3 23:50:12 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 04 Jul 2009 00:50:12 -0300
Subject: stringio+tarfile (or better... zipfile)
References: <4a4d1f4e$0$1116$4fafbaef@reader3.news.tin.it>
	<4a4e66a0$0$1115$4fafbaef@reader4.news.tin.it>
Message-ID: <op.uwix9ym4x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 17:14:22 -0300, superpollo <user at example.net> escribi?:

> following the excellent suggestions received, i tried to adapt the  
> problem to zipfile, and i wrote this:
>
> zip = zipfile.ZipFile(zb , "w" , zipfile.ZIP_DEFLATED)
> for name , buffer in [nb1 , nb2]:
>      zip.writestr(name, buffer.getvalue()*1000)
> zip.close()
>
> it seems to me thaz zipfile has a simpler usability... any comments?

Maybe - but a zip and a tar file are not the same thing.

Now, if you want to say that there should be a common interfase to handle  
all those file formats like tar,zip,bz2: Yes, I agree.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Sat Jul  4 00:04:29 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 04 Jul 2009 01:04:29 -0300
Subject: Reversible Debugging
References: <4A4E4B8B.7090104@gmail.com>
Message-ID: <op.uwiyxrjtx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 03 Jul 2009 15:18:51 -0300, Patrick Sabin  
<patrick.just4fun at gmail.com> escribi?:

> I am interested if there are any python modules, that supports  
> reversible debugging aka stepping backwards. Any links or ideas would be  
> helpful, because I am thinking of implementing something like that.

Do you want reverse execution, like an undo function? Undo all changes  
made by executing some piece of code?
There are many cases where that's hard to do, or impossible. How to undo  
object destruction? How to undo external effects, like writing to files?
You should think carefully what can and cannot be done - good luck!

-- 
Gabriel Genellina



From aahz at pythoncraft.com  Sat Jul  4 00:47:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 21:47:30 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
Message-ID: <h2mmt2$48p$1@panix3.panix.com>

In article <7xhbxtjxtn.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>Simon Forman <sajmikins at gmail.com> writes:
>> 
>> (I like Haskell's Maybe, but saying A is better than B doesn't imply
>> that B is therefore terrible.)
>
>I wouldn't say Python's None is terrible, but the programming style in
>which None is used as a marker for "absent value" is genuinely a
>source of bugs, requiring care when used.  Often it's easy to just
>avoid it and all the bugs that come with it.
>
>Haskell's Maybe type, ML's Option type, and various similar constructs
>in other recently designed languages all are responses to the
>shortcomings of None-like constructs in older languages.  I'm not
>going purely by that one guy's blog post, though I do think that post
>was pretty good.

AFAICT, in order for Maybe and Option to work, you need to have some
kind of static typing system.  Am I missing something?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From aahz at pythoncraft.com  Sat Jul  4 00:50:47 2009
From: aahz at pythoncraft.com (Aahz)
Date: 3 Jul 2009 21:50:47 -0700
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<h2i84f$v2t$1@ger.gmane.org>
	<mailman.2491.1246540910.8015.python-list@python.org>
	<ftps459nklqio3nghaaraniqo3fs9r8ck8@4ax.com>
Message-ID: <h2mn37$hqp$1@panix3.panix.com>

In article <ftps459nklqio3nghaaraniqo3fs9r8ck8 at 4ax.com>,
Tim Roberts  <timr at probo.com> wrote:
>Dave Angel <davea at dejaviewphoto.com> wrote:
>>   
>>You're right of course.  What I was trying to say was it deletes the 
>>reference to the object.  Unlike obj = None, del obj removes the 
>>reference (attribute) entirely. Although I don't know what it should be 
>>called if it's a local variable.  Perhaps it "unbinds" the name.
>
>Yes.  As far as the object is concerned, "obj = None" and "del obj" are
>exactly identical.  In both cases, there is one less binding to the name.
>
>The difference between the two is only whether the name lives on in the
>namespace.
>
>A local variable is (usually) just a name in the local() namespace.

OTOH, Python's ``del`` applies to targets generally, not just names:

>>> L = [1,2,3]
>>> del L[1]
>>> L
[1, 3]
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From upwestdon at gmail.com  Sat Jul  4 02:03:39 2009
From: upwestdon at gmail.com (upwestdon)
Date: Fri, 3 Jul 2009 23:03:39 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
Message-ID: <687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>

On Jul 2, 1:23?pm, Simon Forman <sajmik... at gmail.com> wrote:
> Hey I was hoping to get your opinions on a sort of minor stylistic
> point.
> These two snippets of code are functionally identical. Which would you
> use and why?
> The first one is easier [for me anyway] to read and understand, but
> slightly less efficient, while the second is [marginally] harder to
> follow but more efficient.
>
> ## First snippet
>
> if self.higher is self.lower is None: return
> if self.lower is None: return self.higher
> if self.higher is None: return self.lower
>
> ## Second snippet
>
> if self.higher is None:
> ? ? if self.lower is None:
> ? ? ? ? return
> ? ? return self.lower
> if self.lower is None:
> ? ? return self.higher
>
> What do you think?
>
> (One minor point: in the first snippet, the "is None" in the first
> line is superfluous in the context in which it will be used, the only
> time "self.lower is self.higher" will be true is when they are both
> None.)

How about just:

if not (self.higher and self.lower):
    return self.higher or self.lower


From tkjthingone at gmail.com  Sat Jul  4 02:46:13 2009
From: tkjthingone at gmail.com (Horace Blegg)
Date: Fri, 3 Jul 2009 23:46:13 -0700
Subject: Reversible Debugging
In-Reply-To: <4A4E4B8B.7090104@gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
Message-ID: <b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>

You might consider using a VM with 'save-points'. You run the program (in a
debugger/ida/what have you) to a certain point (logical point would be
if/ifelse/else statements, etc) and save the VM state. Once you've saved,
you continue. If you find the path you've taken isn't what you are after,
you can reload a previous save point and start over, trying a different path
the next time.

This is also somewhat useful if you're trying to debug an error that happens
deep inside of a program, so you can continually jump to the point right
before the error happens, instead of needing to run through the entire
program each time it crashes. Just beware of tunnel vision.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090703/6180961d/attachment-0001.html>

From hanooter at gmail.com  Sat Jul  4 03:33:52 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 00:33:52 -0700 (PDT)
Subject: finding most common elements between thousands of multiple arrays.
Message-ID: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>

Currently I need to find the most common elements in thousands of
arrays within one large array (arround 2 million instances with ~70k
unique elements)

so I set up a dictionary to handle the counting so when I am
iterating  I up the count on the corrosponding dictionary element. I
then iterate through the dictionary and find the 25 most common
elements.

the elements are initially held in a array within an array. so I am am
just trying to find the most common elements between all the arrays
contained in one large array.
my current code looks something like this:
d = {}
for arr in my_array:
-----for i in arr:
#elements are numpy integers and thus are not accepted as dictionary
keys
-----------d[int(i)]=d.get(int(i),0)+1

then I filter things down. but with my algorithm that only takes about
1 sec so I dont need to show it here since that isnt the problem.


But there has to be something better. I have to do this many many
times and it seems silly to iterate through 2 million things just to
get 25. The element IDs are integers and are currently being held in
numpy arrays in a larger array. this ID is what makes up the key to
the dictionary.

 It currently takes about 5 seconds to accomplish this with my current
algorithm.

So does anyone know the best solution or algorithm? I think the trick
lies in matrix intersections but I do not know.


From clp2 at rebertia.com  Sat Jul  4 03:45:32 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 00:45:32 -0700
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <50697b2c0907040045i5316c803ma199bfab10324735@mail.gmail.com>

On Sat, Jul 4, 2009 at 12:33 AM, mclovin<hanooter at gmail.com> wrote:
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
>
> so I set up a dictionary to handle the counting so when I am
> iterating ?I up the count on the corrosponding dictionary element. I
> then iterate through the dictionary and find the 25 most common
> elements.
>
> the elements are initially held in a array within an array. so I am am
> just trying to find the most common elements between all the arrays
> contained in one large array.
> my current code looks something like this:
> d = {}
> for arr in my_array:
> -----for i in arr:
> #elements are numpy integers and thus are not accepted as dictionary
> keys
> -----------d[int(i)]=d.get(int(i),0)+1
>
> then I filter things down. but with my algorithm that only takes about
> 1 sec so I dont need to show it here since that isnt the problem.
>
>
> But there has to be something better. I have to do this many many
> times and it seems silly to iterate through 2 million things just to
> get 25. The element IDs are integers and are currently being held in
> numpy arrays in a larger array. this ID is what makes up the key to
> the dictionary.
>
> ?It currently takes about 5 seconds to accomplish this with my current
> algorithm.
>
> So does anyone know the best solution or algorithm? I think the trick
> lies in matrix intersections but I do not know.

Using a defaultdict
(http://docs.python.org/library/collections.html#collections.defaultdict)
would speed it up (but only slightly) and make it clearer to read.

Cheers,
Chris
-- 
http://blog.rebertia.com


From patrick.just4fun at gmail.com  Sat Jul  4 04:04:08 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Sat, 04 Jul 2009 10:04:08 +0200
Subject: Reversible Debugging
In-Reply-To: <op.uwiyxrjtx6zn5v@lepton.softlabbsas.com.ar>
References: <4A4E4B8B.7090104@gmail.com>
	<op.uwiyxrjtx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A4F0CF8.5090101@gmail.com>

Gabriel Genellina schrieb:
> Do you want reverse execution, like an undo function? Undo all changes 
> made by executing some piece of code?
I am not completly sure, if I really want to make exact undo, i.e. 
undoing commands by reversing all their effects, or just restoring the
program state to an arbitrary state of its history, which would not 
effect things like files.
> There are many cases where that's hard to do, or impossible. How to 
> undo object destruction? How to undo external effects, like writing to 
> files?
Object destruction should not be a big problem to restore. But writing 
files or other resources is because it is not guaranted that it is even 
possible or wanted.
I considered either ignoring undoing external commands completly or 
adding some plugin system to do it.
> You should think carefully what can and cannot be done - good luck!
>


From andreengels at gmail.com  Sat Jul  4 04:04:42 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sat, 4 Jul 2009 10:04:42 +0200
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>

On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
>
> so I set up a dictionary to handle the counting so when I am
> iterating ?I up the count on the corrosponding dictionary element. I
> then iterate through the dictionary and find the 25 most common
> elements.
>
> the elements are initially held in a array within an array. so I am am
> just trying to find the most common elements between all the arrays
> contained in one large array.
> my current code looks something like this:
> d = {}
> for arr in my_array:
> -----for i in arr:
> #elements are numpy integers and thus are not accepted as dictionary
> keys
> -----------d[int(i)]=d.get(int(i),0)+1
>
> then I filter things down. but with my algorithm that only takes about
> 1 sec so I dont need to show it here since that isnt the problem.
>
>
> But there has to be something better. I have to do this many many
> times and it seems silly to iterate through 2 million things just to
> get 25. The element IDs are integers and are currently being held in
> numpy arrays in a larger array. this ID is what makes up the key to
> the dictionary.
>
> ?It currently takes about 5 seconds to accomplish this with my current
> algorithm.
>
> So does anyone know the best solution or algorithm? I think the trick
> lies in matrix intersections but I do not know.

There's no better algorithm for the general case. No method of
checking the matrices using less than 2000000-x look-ups will ensure
you that there's not a new value with x occurences lurking somewhere.

However, if you need this information more often, and if the number of
values that changes in between is small compared to the total size of
the matrices, you could make a gain in subsequent calculations by
remembering part results. Depending on the situation you could for
example keep the dictionary with the counts and update it each time,
or keep such a dictionary for each "big" matrix, and set a flag when
that dictionary is not up-to-date any more

.

-- 
Andr? Engels, andreengels at gmail.com


From Lacrima.Maxim at gmail.com  Sat Jul  4 04:12:10 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Sat, 4 Jul 2009 01:12:10 -0700 (PDT)
Subject: urllib with x509 certs
Message-ID: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>

Hello!

I am trying to use urllib to fetch some internet resources, using my
client x509 certificate.
I have divided my .p12 file into mykey.key and mycert.cer files.
Then I use following approach:
>>> import urllib
>>> url = 'https://example.com'
>>> xml = '''<request>
... <somexml>somexml</somexml>
</request>'''
>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
>>> f = opener.open(url, xml)

This works Ok! But every time I am asked to enter PEM pass phrase,
which I specified during dividing my .p12 file.
So my question... What should I do to make my code fetch any url
automatically (without asking me every time to enter pass phrase)?
As I understand there is impossible to specify pass phrase while
constructing URLopener.
So what should I do?

With regards, Max
(sorry if my English isn't very proper)


From __peter__ at web.de  Sat Jul  4 04:21:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 04 Jul 2009 10:21:13 +0200
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
Message-ID: <h2n3d8$kvq$00$1@news.t-online.com>

Icarus wrote:

> I'm working on a serial protocol analyzer in python.  We have an
> application written by someone else in MFC but we need something that
> is cross platform.  I intended to implement the GUI portion in Tkinter
> but am having trouble.
> 
> The idea is that I will read messages from the serial port and output
> them to a Tkinter Text object initially.  Eventually it will have
> other functionality but that's it for the short term.  I've written
> this little test app to experiment with putting things on the GUI via
> a Queue which is polled by the Tkinter loop.
> 
> On some machines this code works fine and I get whatever I type in
> displayed in the Text widget.  On others I get errors like this as
> soon as I start it running.
> 
> error in background error handler:
> out of stack space (infinite loop?)
>     while executing
> "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
>     while execu..."
> 
> 
> I don't understand why on some machines it works exactly as expected
> and on others it acts the same way Tkinter does when I call functions
> directly from outside the Tkinter thread.  Does anyone have any
> suggestions?  The full code as appended below.  Thanks in advance.
> 
> [code]
> 
> import Queue
> 
> class functionQueue:
> 
>     def __init__(self, root = None, timeout = 250):
> 
>         self.functionQueue = Queue.Queue()
>         self.root = root
>         self.timeout = timeout
> 
>         if(self.root):
>             self.pop_function(root)
> 
> 
>     def pop_function(self, root = None):
> 
>         try:
>             funcArgList = self.functionQueue.get(block = False)
>         except Queue.Empty:
>             pass
>         else:
>             try:
>                 funcArgList[0](*funcArgList[1])
>             except:
>                 try:
>                     print "Failed to call function", funcArgList[0]
>                 except:
>                     print "Failed to call function"
> 
>         if(root):
>             root.after(self.timeout, lambda: self.pop_function
> (self.root))
> 
>     def add_function(self, function, argList):
> 
>         try:
>             self.functionQueue.put([function, argList])
>         except:
>             pass
> 
> 
> if( __name__ == '__main__'):
> 
>     import Tkinter
>     import thread
> 
>     text = Tkinter.Text()
>     text.pack()
> 
>     myQueue = functionQueue(text, 50)
> 
>     def gui_loop():
>         try:
>             text.mainloop()
>         except:
>             import os
>             os._exit(1)
> 
>     thread.start_new_thread(text.mainloop, ())
> 
>     while(True):
>         usrInput = raw_input()
> 
>         if(usrInput == "-1"):
>             import os
>             os._exit(0)
> 
>         myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>         myQueue.add_function(text.see, ['end'])
> 
> [/code]

I can make it work over here by putting the UI into the main thread, as 
suggested by http://effbot.org/zone/tkinter-threads.htm:

import Queue
import Tkinter
import threading

class FunctionQueue:
    # unchanged

def input_loop():
    while True:
        try:
            usrInput = raw_input()
        except EOFError:
            break
        myQueue.add_function(text.insert, ['end', usrInput + "\n"])
        myQueue.add_function(text.see, ['end'])
    myQueue.add_function(text.quit, [])

if __name__ == '__main__':
    text = Tkinter.Text()
    text.pack()

    myQueue = FunctionQueue(text, 50)
    threading.Thread(target=input_loop).start()
    text.mainloop()

Peter




From clp2 at rebertia.com  Sat Jul  4 04:24:36 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 01:24:36 -0700
Subject: urllib with x509 certs
In-Reply-To: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
Message-ID: <50697b2c0907040124j4e309c25j77e01c8127711f80@mail.gmail.com>

On Sat, Jul 4, 2009 at 1:12 AM, Lacrima<Lacrima.Maxim at gmail.com> wrote:
> Hello!
>
> I am trying to use urllib to fetch some internet resources, using my
> client x509 certificate.
> I have divided my .p12 file into mykey.key and mycert.cer files.
> Then I use following approach:
>>>> import urllib
>>>> url = 'https://example.com'
>>>> xml = '''<request>
> ... <somexml>somexml</somexml>
> </request>'''
>>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
>>>> f = opener.open(url, xml)
>
> This works Ok! But every time I am asked to enter PEM pass phrase,
> which I specified during dividing my .p12 file.
> So my question... What should I do to make my code fetch any url
> automatically (without asking me every time to enter pass phrase)?
> As I understand there is impossible to specify pass phrase while
> constructing URLopener.
> So what should I do?

Subclass FancyURLopener
[http://docs.python.org/library/urllib.html#urllib.FancyURLopener],
overriding the prompt_user_passwd() method
[http://docs.python.org/library/urllib.html#urllib.FancyURLopener.prompt_user_passwd].
Then use an instance of your subclass instead of URLopener.

Cheers,
Chris
-- 
http://blog.rebertia.com


From patrick.just4fun at gmail.com  Sat Jul  4 04:33:03 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Sat, 04 Jul 2009 10:33:03 +0200
Subject: Reversible Debugging
In-Reply-To: <b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
Message-ID: <4A4F13BF.9050605@gmail.com>

Horace Blegg schrieb:
> You might consider using a VM with 'save-points'. You run the program 
> (in a debugger/ida/what have you) to a certain point (logical point 
> would be if/ifelse/else statements, etc) and save the VM state. Once 
> you've saved, you continue. If you find the path you've taken isn't 
> what you are after, you can reload a previous save point and start 
> over, trying a different path the next time.
That was my idea to implement it. I thought of taking snapshots of the 
current state every time a "unredoable instruction", e.g random number 
generation, is done.  For every other instruction I count the number of 
instructions done since the last snapshot. So I can go back one 
instruction by restoring to the previous state and go the number of 
instructions minus one forward.

> This is also somewhat useful if you're trying to debug an error that 
> happens deep inside of a program, so you can continually jump to the 
> point right before the error happens, instead of needing to run 
> through the entire program each time it crashes. Just beware of tunnel 
> vision.
I think of implementing some snapshot/restore mechanism first. That may 
help in many other situations.


From stef.mientki at gmail.com  Sat Jul  4 05:25:38 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sat, 04 Jul 2009 11:25:38 +0200
Subject: Reversible Debugging
In-Reply-To: <4A4E4B8B.7090104@gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
Message-ID: <4A4F2012.2020206@gmail.com>

Patrick Sabin wrote:
> Hello,
>
> I am interested if there are any python modules, that supports 
> reversible debugging aka stepping backwards. Any links or ideas would 
> be helpful, because I am thinking of implementing something like that.
>
In some cases it would be nice to have something like that,
specially in combination with a "normal" debugger,
which allows you to change values on the flight,
like winpdb.

cheers,
Stef
> Thanks in advance,
> Patrick



From martin at v.loewis.de  Sat Jul  4 05:38:15 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sat, 04 Jul 2009 11:38:15 +0200
Subject: urllib with x509 certs
In-Reply-To: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
Message-ID: <4a4f2307$0$8384$9b622d9e@news.freenet.de>

> This works Ok! But every time I am asked to enter PEM pass phrase,
> which I specified during dividing my .p12 file.
> So my question... What should I do to make my code fetch any url
> automatically (without asking me every time to enter pass phrase)?
> As I understand there is impossible to specify pass phrase while
> constructing URLopener.
> So what should I do?

You can remove the passphrase on the private key, e.g. with the
openssl rsa utility.

Regards,
Martin


From banibrata.dutta at gmail.com  Sat Jul  4 05:47:18 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Sat, 4 Jul 2009 15:17:18 +0530
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <h2lvta$3f9$1@ger.gmane.org>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
Message-ID: <3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>

QuoteGoke Aruna <pyklass at gmail.com>

what am saying is reading the ITU info on USSD, is it possible to use python

to write the application SS7 with support for TCAP/MAP talking to E1
card to do the ss7 signalling.

As Chris mentioned "possible, but probably not easy". AFAIK, not much of
what you might need exists in form of existing Python modules, if that's
what you were thinking -- and especially in the Open-source form. The only
open-source initiative in the SS7 domain that I am aware of, is the openss7
(http://www.openss7.org/), which has 'some' software available. No personal
experience though, API's are C/C++ AFAIR, and last I'd checked, the status
wasn't 'practically usable' in functionality terms. If they offer
functionality of the ITU-T SS7 stack upto the TCAP layer, exposing a C/C++
API to create dialogs, create components, populate and send them etc. (usual
TCAP Primitives), then as Chris mentions, you could have Python wrappers
(ctypes, swig...). Then, for the MAP layer, which is largely ASN.1 BER
encoding/decoding, you'd need such functionality in Python. There are some
ASN.1 BER codec implementations having Python API/bindings, but AFAIK, they
are largely domain/application specific (s.a. for SNMP), and not generic or
robust enough. Given the API's however, writing any application s.a. for
performing some "business-logic" on receiving or before sending USSD / SMS
message in Python, that's a no-brainer ! :-)
If however, you want to implement the whole SS7 stack in Python --
everything that Chris wrote is accurate, and that's potentially (and the
most obvious) way you'd have to implement it.

-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/8b1e6c9c/attachment-0001.html>

From clp2 at rebertia.com  Sat Jul  4 05:50:18 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 02:50:18 -0700
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
	<3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
Message-ID: <50697b2c0907040250o8e6d9baqc1b368c2d0c547ff@mail.gmail.com>

On Sat, Jul 4, 2009 at 2:47 AM, Banibrata
Dutta<banibrata.dutta at gmail.com> wrote:
> QuoteGoke Aruna <pyklass at gmail.com>
>>
>> what am saying is reading the ITU info on USSD, is it possible to use
>> python
>>
>> to write the application SS7 with support for TCAP/MAP talking to E1 card
>> to do the ss7 signalling.
>
> As Chris mentioned "possible, but probably not easy". AFAIK, not much of

s/Chris/Dennis/

Credit where credit is due. I merely gave a PyPI link.

Cheers,
Chris
-- 
http://blog.rebertia.com


From banibrata.dutta at gmail.com  Sat Jul  4 05:53:19 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Sat, 4 Jul 2009 15:23:19 +0530
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
	<3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
Message-ID: <3de8e1f70907040253r60211297o8dbea679d3f5273a@mail.gmail.com>

BTW, if you just want to be able to send/receive SMS's in a Python
application, there are several alternatives.
1. Most operators, or 3rd party bulk-SMS vendors (who resell SMS capacity
from operators at a premium but in smaller bundles than what an operator
would sell), offer --
  a. HTTP based mechanism to send/receive messages
  b. SMPP protocol. OpenSMPP has a C API, and you could create Python
wrappers for same.

2. For very low volume application, you could use the Serial (or Serial
emulation over USB/Bluetooth) way, i.e. using "AT" commandset of a tethered
GSM mobile (with inbuilt GSM modem), or a separate GSM-modem (PCMCIA,
USB,...) via Python, to send / receive SMS's.

On Sat, Jul 4, 2009 at 3:17 PM, Banibrata Dutta
<banibrata.dutta at gmail.com>wrote:

> QuoteGoke Aruna <pyklass at gmail.com>
>
> what am saying is reading the ITU info on USSD, is it possible to use python
>
> to write the application SS7 with support for TCAP/MAP talking to E1 card to do the ss7 signalling.
>
> As Chris mentioned "possible, but probably not easy". AFAIK, not much of
> what you might need exists in form of existing Python modules, if that's
> what you were thinking -- and especially in the Open-source form. The only
> open-source initiative in the SS7 domain that I am aware of, is the openss7
> (http://www.openss7.org/), which has 'some' software available. No
> personal experience though, API's are C/C++ AFAIR, and last I'd checked, the
> status wasn't 'practically usable' in functionality terms. If they offer
> functionality of the ITU-T SS7 stack upto the TCAP layer, exposing a C/C++
> API to create dialogs, create components, populate and send them etc. (usual
> TCAP Primitives), then as Chris mentions, you could have Python wrappers
> (ctypes, swig...). Then, for the MAP layer, which is largely ASN.1 BER
> encoding/decoding, you'd need such functionality in Python. There are some
> ASN.1 BER codec implementations having Python API/bindings, but AFAIK, they
> are largely domain/application specific (s.a. for SNMP), and not generic or
> robust enough. Given the API's however, writing any application s.a. for
> performing some "business-logic" on receiving or before sending USSD / SMS
> message in Python, that's a no-brainer ! :-)
> If however, you want to implement the whole SS7 stack in Python --
> everything that Chris wrote is accurate, and that's potentially (and the
> most obvious) way you'd have to implement it.
>
> --
> regards,
> Banibrata
> http://www.linkedin.com/in/bdutta
>



-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/9ad1cd32/attachment-0001.html>

From banibrata.dutta at gmail.com  Sat Jul  4 05:54:08 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Sat, 4 Jul 2009 15:24:08 +0530
Subject: is it possible to write USSD / SMS /SS7 apps in python
In-Reply-To: <50697b2c0907040250o8e6d9baqc1b368c2d0c547ff@mail.gmail.com>
References: <4A4DC768.40604@gmail.com>
	<50697b2c0907030221i5fa25134s6905ac9c2da39358@mail.gmail.com>
	<30ef32480907030231q3d02564dse0a5ecad3810805@mail.gmail.com>
	<h2lvta$3f9$1@ger.gmane.org>
	<3de8e1f70907040247t50e447feu6ed3ec5d5887e79b@mail.gmail.com>
	<50697b2c0907040250o8e6d9baqc1b368c2d0c547ff@mail.gmail.com>
Message-ID: <3de8e1f70907040254ucc68ff3l65e791b0457678aa@mail.gmail.com>

On Sat, Jul 4, 2009 at 3:20 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Sat, Jul 4, 2009 at 2:47 AM, Banibrata
> Dutta<banibrata.dutta at gmail.com> wrote:
> > QuoteGoke Aruna <pyklass at gmail.com>
> >>
> >> what am saying is reading the ITU info on USSD, is it possible to use
> >> python
> >>
> >> to write the application SS7 with support for TCAP/MAP talking to E1
> card
> >> to do the ss7 signalling.
> >
> > As Chris mentioned "possible, but probably not easy". AFAIK, not much of
>
> s/Chris/Dennis/
>
> Credit where credit is due. I merely gave a PyPI link.
>

Indeed. Thanks Chris, sorry Dennis.

-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/07f515b4/attachment-0001.html>

From vilya.harvey at gmail.com  Sat Jul  4 05:55:44 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sat, 4 Jul 2009 10:55:44 +0100
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
Message-ID: <6aef848f0907040255y296c5ea1n2fff44c859cf12ab@mail.gmail.com>

2009/7/4 Andre Engels <andreengels at gmail.com>:
> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>> Currently I need to find the most common elements in thousands of
>> arrays within one large array (arround 2 million instances with ~70k
>> unique elements)
>>
>> so I set up a dictionary to handle the counting so when I am
>> iterating ?I up the count on the corrosponding dictionary element. I
>> then iterate through the dictionary and find the 25 most common
>> elements.
>>
>> the elements are initially held in a array within an array. so I am am
>> just trying to find the most common elements between all the arrays
>> contained in one large array.
>> my current code looks something like this:
>> d = {}
>> for arr in my_array:
>> -----for i in arr:
>> #elements are numpy integers and thus are not accepted as dictionary
>> keys
>> -----------d[int(i)]=d.get(int(i),0)+1
>>
>> then I filter things down. but with my algorithm that only takes about
>> 1 sec so I dont need to show it here since that isnt the problem.
>>
>>
>> But there has to be something better. I have to do this many many
>> times and it seems silly to iterate through 2 million things just to
>> get 25. The element IDs are integers and are currently being held in
>> numpy arrays in a larger array. this ID is what makes up the key to
>> the dictionary.
>>
>> ?It currently takes about 5 seconds to accomplish this with my current
>> algorithm.
>>
>> So does anyone know the best solution or algorithm? I think the trick
>> lies in matrix intersections but I do not know.
>
> There's no better algorithm for the general case. No method of
> checking the matrices using less than 2000000-x look-ups will ensure
> you that there's not a new value with x occurences lurking somewhere.

Try flattening the arrays into a single large array & sorting it. Then
you can just iterate over the large array counting as you go; you only
ever have to insert into the dict once for each value and there's no
lookups in the dict. I don't know numpy, so there's probably a more
efficient way to write this, but this should show what I'm talking
about:

big_arr = sorted(reduce(list.__add__, my_array, []))
counts = {}
last_val = big_arr[0]
count = 0
for val in big_arr:
    if val == last_val:
        count += 1
    else:
        counts[last_val] = count
        count = 0
        last_val = val
counts[last_val] = count    # to get the count for the last value.

If flattening the arrays isn't practical, you may still get some
improvements by sorting them individually and applying the same
principle to each of them:

counts = {}
for arr in my_array:
    sorted_arr = sorted(arr)
    last_val = sorted_arr[0]
    count = 0
    for val in sorted_arr:
        if val == last_val:
            count += 1
        else:
            counts[last_val] = counts.get(last_val, 0) + count
            count = 0
            last_val = val
    counts[last_val] = counts.get(last_val, 0) + count

Hope that helps...

Vil.


From parikshatdubey at gmail.com  Sat Jul  4 06:06:11 2009
From: parikshatdubey at gmail.com (Parikshat Dubey)
Date: Sat, 4 Jul 2009 15:36:11 +0530
Subject: Calling C or C++ Functions inside Python script
Message-ID: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>

Hi,

Is this possible to call C functions(inbuilt or user defined) inside python
script.If yes, please illustrate how it can be done.
 Thanks,
Parikshat Dubey
-- 
-----Fear not the path of truth, for the lack of people walking on it.


----Practice yourself, for heaven's sake, in little things; and thence
proceed to
greater.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/ef503323/attachment-0001.html>

From Lacrima.Maxim at gmail.com  Sat Jul  4 06:08:40 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Sat, 4 Jul 2009 03:08:40 -0700 (PDT)
Subject: urllib with x509 certs
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<mailman.2595.1246695878.8015.python-list@python.org>
Message-ID: <df337b53-9194-4ace-bc45-e2b5fbc7c641@b9g2000yqm.googlegroups.com>

On Jul 4, 11:24?am, Chris Rebert <c... at rebertia.com> wrote:
> On Sat, Jul 4, 2009 at 1:12 AM, Lacrima<Lacrima.Ma... at gmail.com> wrote:
> > Hello!
>
> > I am trying to use urllib to fetch some internet resources, using my
> > client x509 certificate.
> > I have divided my .p12 file into mykey.key and mycert.cer files.
> > Then I use following approach:
> >>>> import urllib
> >>>> url = 'https://example.com'
> >>>> xml = '''<request>
> > ... <somexml>somexml</somexml>
> > </request>'''
> >>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
> >>>> f = opener.open(url, xml)
>
> > This works Ok! But every time I am asked to enter PEM pass phrase,
> > which I specified during dividing my .p12 file.
> > So my question... What should I do to make my code fetch any url
> > automatically (without asking me every time to enter pass phrase)?
> > As I understand there is impossible to specify pass phrase while
> > constructing URLopener.
> > So what should I do?
>
> Subclass FancyURLopener
> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener],
> overriding the prompt_user_passwd() method
> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener.prom...].
> Then use an instance of your subclass instead of URLopener.
>
> Cheers,
> Chris
> --http://blog.rebertia.com

Hi Chris,
Thanks for your quick reply.
According to docs the return value of prompt_user_passwd() method
should be a tuple (user, password), but there is no user when
authenticating with certificate. So how should I use this method? This
doesn't work:
>>> import urllib
>>> class MyOpener(urllib.FancyURLopener):
...      def prompt_user_passwd(self, host, realm):
...          return ('password')
...


With regards, Max


From Lacrima.Maxim at gmail.com  Sat Jul  4 06:14:17 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Sat, 4 Jul 2009 03:14:17 -0700 (PDT)
Subject: urllib with x509 certs
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<4a4f2307$0$8384$9b622d9e@news.freenet.de>
Message-ID: <a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>

On Jul 4, 12:38?pm, "Martin v. L?wis" <mar... at v.loewis.de> wrote:
> > This works Ok! But every time I am asked to enter PEM pass phrase,
> > which I specified during dividing my .p12 file.
> > So my question... What should I do to make my code fetch any url
> > automatically (without asking me every time to enter pass phrase)?
> > As I understand there is impossible to specify pass phrase while
> > constructing URLopener.
> > So what should I do?
>
> You can remove the passphrase on the private key, e.g. with the
> openssl rsa utility.
>
> Regards,
> Martin

Hi Martin!

Thanks for the reply. I want my key to be as secure as possible. So I
will remove pass phrase if only there is no other possibility to go
through authentication.

With regards, Max


From clp2 at rebertia.com  Sat Jul  4 06:27:46 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 03:27:46 -0700
Subject: urllib with x509 certs
In-Reply-To: <df337b53-9194-4ace-bc45-e2b5fbc7c641@b9g2000yqm.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<mailman.2595.1246695878.8015.python-list@python.org>
	<df337b53-9194-4ace-bc45-e2b5fbc7c641@b9g2000yqm.googlegroups.com>
Message-ID: <50697b2c0907040327w23b7f0eal13934bc8d33c7231@mail.gmail.com>

2009/7/4 Lacrima <Lacrima.Maxim at gmail.com>:
> On Jul 4, 11:24?am, Chris Rebert <c... at rebertia.com> wrote:
>> On Sat, Jul 4, 2009 at 1:12 AM, Lacrima<Lacrima.Ma... at gmail.com> wrote:
>> > Hello!
>>
>> > I am trying to use urllib to fetch some internet resources, using my
>> > client x509 certificate.
>> > I have divided my .p12 file into mykey.key and mycert.cer files.
>> > Then I use following approach:
>> >>>> import urllib
>> >>>> url = 'https://example.com'
>> >>>> xml = '''<request>
>> > ... <somexml>somexml</somexml>
>> > </request>'''
>> >>>> opener = urllib.URLopener(key_file = 'mykey.key', cert_file = 'mycert.cer')
>> >>>> f = opener.open(url, xml)
>>
>> > This works Ok! But every time I am asked to enter PEM pass phrase,
>> > which I specified during dividing my .p12 file.
>> > So my question... What should I do to make my code fetch any url
>> > automatically (without asking me every time to enter pass phrase)?
>> > As I understand there is impossible to specify pass phrase while
>> > constructing URLopener.
>> > So what should I do?
>>
>> Subclass FancyURLopener
>> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener],
>> overriding the prompt_user_passwd() method
>> [http://docs.python.org/library/urllib.html#urllib.FancyURLopener.prom...].
>> Then use an instance of your subclass instead of URLopener.
>>
>> Cheers,
>> Chris
>> --http://blog.rebertia.com
>
> Hi Chris,
> Thanks for your quick reply.
> According to docs the return value of prompt_user_passwd() method
> should be a tuple (user, password), but there is no user when
> authenticating with certificate. So how should I use this method? This
> doesn't work:
>>>> import urllib
>>>> class MyOpener(urllib.FancyURLopener):
> ... ? ? ?def prompt_user_passwd(self, host, realm):
> ... ? ? ? ? ?return ('password')

Only a guess:

def prompt_user_passwd(self, host, realm):
    return ('', 'password')

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Sat Jul  4 06:29:30 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 4 Jul 2009 03:29:30 -0700
Subject: Calling C or C++ Functions inside Python script
In-Reply-To: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
References: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
Message-ID: <50697b2c0907040329w5085b9c9xa8d6a2aaae9667de@mail.gmail.com>

On Sat, Jul 4, 2009 at 3:06 AM, Parikshat Dubey<parikshatdubey at gmail.com> wrote:
> Hi,
>
> Is this possible to call C functions(inbuilt or user defined) inside python
> script.If yes, please illustrate how it can be done.

The `ctypes` module:
http://docs.python.org/library/ctypes.html
Note: does not work w/ C++ directly.

Cheers,
Chris
-- 
http://blog.rebertia.com


From martin at v.loewis.de  Sat Jul  4 07:09:51 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sat, 04 Jul 2009 13:09:51 +0200
Subject: urllib with x509 certs
In-Reply-To: <a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<4a4f2307$0$8384$9b622d9e@news.freenet.de>
	<a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>
Message-ID: <4A4F387F.7050804@v.loewis.de>

> Thanks for the reply. I want my key to be as secure as possible. So I
> will remove pass phrase if only there is no other possibility to go
> through authentication.

And you put the passphrase into the source code instead? How does it
make that more secure?

Regards,
Martin


From larudwer at freenet.de  Sat Jul  4 08:26:27 2009
From: larudwer at freenet.de (larudwer)
Date: Sat, 4 Jul 2009 14:26:27 +0200
Subject: psyco V2 beta2  benchmark
Message-ID: <h2nhhs$g5m$00$1@news.t-online.com>

just out of curiosity i've downloaded the latest Version of Psyco V2 Beta 2 
and run the benchmarks against the old Version of psyco 1.6

Because it might be of common interest, i am posting the results here.

My machine is a Pentium D 3.2 Ghz running Windows XP SP 3 and Python 2.6.2.
Psyco V2 was built with 4.3.3-tdm-1 mingw32 with optimisation flags changed 
to -O3


Benchmark                                 | avg. Base time | psyco 1.6 time 
| psyco 2.0 time | ratio     | possible error +-
time_anyall all_bool_genexp               | 2.270          | 2.250 
| 2.420          | 0.930     | 8.3 %
time_anyall all_bool_listcomp             | 3.450          | 1.900 
| 1.910          | 0.995     | 0.0 %
time_anyall all_genexp                    | 1.970          | 1.940 
| 2.160          | 0.898     | 9.6 %
time_anyall all_listcomp                  | 3.485          | 1.660 
| 1.660          | 1.000     | 1.4 %
time_anyall all_loop                      | 0.665          | 0.090 
| 0.090          | 1.000     | 4.4 %
time_anyall any_bool_genexp               | 2.215          | 2.130 
| 2.340          | 0.910     | 10.0 %
time_anyall any_bool_listcomp             | 3.620          | 1.930 
| 1.940          | 0.995     | 9.0 %
time_anyall any_genexp                    | 1.985          | 1.920 
| 2.180          | 0.881     | 10.1 %
time_anyall any_listcomp                  | 3.360          | 1.680 
| 1.680          | 1.000     | 8.0 %
time_anyall any_loop                      | 0.660          | 0.090 
| 0.090          | 1.000     | 3.0 %
time_builtins chr(i)                      | 2.420          | 0.010 
| 0.010          | 1.000     | 0.0 %
time_builtins hash(i)                     | 1.280          | 0.370 
| 0.080          | 4.625     | 8.1 %
time_builtins int(round(f))               | 2.635          | 1.510 
| 1.120          | 1.348     | 0.4 %
time_builtins min                         | 0.535          | 0.520 
| 0.120          | 4.333     | 1.9 %
time_builtins min_kw                      | 4.430          | 4.400 
| 0.160          | 27.500    | 0.5 %
time_builtins ord(i)                      | 0.320          | 0.000 
| 0.000          | 1.000     | 6.5 %
time_builtins pow                         | 0.345          | 0.230 
| 0.150          | 1.533     | 2.9 %
time_builtins reduce                      | 0.735          | 0.710 
| 0.020          | 35.498    | 1.4 %
time_builtins round(f)                    | 1.720          | 0.890 
| 0.400          | 2.225     | 1.2 %
time_builtins sums                        | 0.180          | 0.180 
| 0.100          | 1.800     | 0.0 %
time_fib matrix                           | 0.425          | 0.360 
| 0.360          | 1.000     | 2.3 %
time_fib recursive                        | 0.000          | 0.000 
| 0.000          | 1.000     | 0.0 %
time_fib takahashi                        | 0.410          | 0.320 
| 0.330          | 0.970     | 0.0 %
time_generators call next just many times | 0.900          | 0.630 
| 0.970          | 0.649     | 4.3 %
time_generators iterate just many times   | 0.660          | 0.550 
| 0.950          | 0.579     | 3.1 %
time_generators send and loop 1000        | 2.805          | 2.540 
| 0.060          | 42.333    | 9.8 %
time_generators send call loop 1000       | 2.505          | 2.940 
| 0.060          | 48.999    | 10.9 %
time_generators send just many times      | 1.280          | 0.590 
| 0.980          | 0.602     | 3.1 %
time_iter iter                            | 1.490          | 0.590 
| 0.440          | 1.341     | 5.5 %
time_math floats                          | 2.910          | 1.500 
| 1.630          | 0.920     | 0.7 %
time_properties method_get                | 0.935          | 0.120 
| 0.130          | 0.923     | 1.1 %
time_properties method_set                | 1.005          | 0.170 
| 0.180          | 0.944     | 1.0 %
time_properties property_get              | 0.960          | 0.740 
| 0.100          | 7.400     | 2.1 %
time_properties property_set              | 1.020          | 0.920 
| 0.930          | 0.989     | 0.0 %
time_properties pyproperty_get            | 1.535          | 1.310 
| 0.140          | 9.357     | 0.7 %
time_properties pyproperty_set            | 1.030          | 0.920 
| 0.930          | 0.989     | 2.0 %
time_subdist subdist(i)                   | 3.665          | 1.640 
| 6.140          | 0.267     | 0.8 %
time_sums rounding                        | 0.800          | 0.790 
| 0.810          | 0.975     | 2.5 %


Running new timings with 
C:\Programme\GNU\python26\lib\site-packages\psyco\_psyco.pyd Sat Jul 04 
12:09:07 2009

time_anyall    : all_bool_genexp                plain:   2.36     psyco: 
2.42     ratio:  0.97
time_anyall    : all_bool_listcomp              plain:   3.45     psyco: 
1.91     ratio:  1.80
time_anyall    : all_genexp                     plain:   2.06     psyco: 
2.16     ratio:  0.95
time_anyall    : all_listcomp                   plain:   3.51     psyco: 
1.66     ratio:  2.11
time_anyall    : all_loop                       plain:   0.65     psyco: 
0.09     ratio:  7.03
time_anyall    : any_bool_genexp                plain:   2.32     psyco: 
2.34     ratio:  0.99
time_anyall    : any_bool_listcomp              plain:   3.45     psyco: 
1.94     ratio:  1.78
time_anyall    : any_genexp                     plain:   2.08     psyco: 
2.18     ratio:  0.96
time_anyall    : any_listcomp                   plain:   3.49     psyco: 
1.68     ratio:  2.08
time_anyall    : any_loop                       plain:   0.65     psyco: 
0.09     ratio:  7.05
time_builtins  : chr(i)                         plain:   2.42     psyco: 
0.01     ratio: 197.40
time_builtins  : hash(i)                        plain:   1.33     psyco: 
0.08     ratio: 17.69
time_builtins  : int(round(f))                  plain:   2.63     psyco: 
1.12     ratio:  2.36
time_builtins  : min                            plain:   0.53     psyco: 
0.12     ratio:  4.28
time_builtins  : min_kw                         plain:   4.44     psyco: 
0.16     ratio: 28.58
time_builtins  : ord(i)                         plain:   0.33     psyco: 
0.00     ratio: 123.57
time_builtins  : pow                            plain:   0.34     psyco: 
0.15     ratio:  2.24
time_builtins  : reduce                         plain:   0.74     psyco: 
0.02     ratio: 40.93
time_builtins  : round(f)                       plain:   1.73     psyco: 
0.40     ratio:  4.38
time_builtins  : sums                           plain:   0.18     psyco: 
0.10     ratio:  1.80
time_fib       : matrix                         plain:   0.42     psyco: 
0.36     ratio:  1.18
time_fib       : recursive                      plain:   0.00     psyco: 
0.00     ratio: 19.45
time_fib       : takahashi                      plain:   0.41     psyco: 
0.33     ratio:  1.25
time_generators: send call loop 1000            plain:   2.36     psyco: 
0.06     ratio: 41.30
time_generators: send and loop 1000             plain:   2.66     psyco: 
0.06     ratio: 46.69
time_generators: send just many times           plain:   1.26     psyco: 
0.98     ratio:  1.29
time_generators: iterate just many times        plain:   0.67     psyco: 
0.95     ratio:  0.70
time_generators: call next just many times      plain:   0.88     psyco: 
0.97     ratio:  0.91
time_iter      : iter                           plain:   1.53     psyco: 
0.44     ratio:  3.47
time_math      : floats                         plain:   2.90     psyco: 
1.63     ratio:  1.78
time_properties: method_get                     plain:   0.93     psyco: 
0.13     ratio:  7.22
time_properties: method_set                     plain:   1.00     psyco: 
0.18     ratio:  5.61
time_properties: property_get                   plain:   0.95     psyco: 
0.10     ratio:  9.26
time_properties: property_set                   plain:   1.02     psyco: 
0.93     ratio:  1.09
time_properties: pyproperty_get                 plain:   1.54     psyco: 
0.14     ratio: 10.80
time_properties: pyproperty_set                 plain:   1.04     psyco: 
0.93     ratio:  1.12
time_subdist   : subdist(i)                     plain:   3.68     psyco: 
6.14     ratio:  0.60
time_sums      : rounding                       plain:   0.79     psyco: 
0.81     ratio:  0.98


Running new timings with original psyco

time_anyall    : all_bool_genexp                plain:   2.18     psyco: 
2.25     ratio:  0.97
time_anyall    : all_bool_listcomp              plain:   3.45     psyco: 
1.90     ratio:  1.82
time_anyall    : all_genexp                     plain:   1.88     psyco: 
1.94     ratio:  0.97
time_anyall    : all_listcomp                   plain:   3.46     psyco: 
1.66     ratio:  2.09
time_anyall    : all_loop                       plain:   0.68     psyco: 
0.09     ratio:  7.34
time_anyall    : any_bool_genexp                plain:   2.11     psyco: 
2.13     ratio:  0.99
time_anyall    : any_bool_listcomp              plain:   3.79     psyco: 
1.93     ratio:  1.96
time_anyall    : any_genexp                     plain:   1.89     psyco: 
1.92     ratio:  0.98
time_anyall    : any_listcomp                   plain:   3.23     psyco: 
1.68     ratio:  1.92
time_anyall    : any_loop                       plain:   0.67     psyco: 
0.09     ratio:  7.26
time_builtins  : chr(i)                         plain:   2.42     psyco: 
0.01     ratio: 197.10
time_builtins  : hash(i)                        plain:   1.23     psyco: 
0.37     ratio:  3.30
time_builtins  : int(round(f))                  plain:   2.64     psyco: 
1.51     ratio:  1.75
time_builtins  : min                            plain:   0.54     psyco: 
0.52     ratio:  1.03
time_builtins  : min_kw                         plain:   4.42     psyco: 
4.40     ratio:  1.00
time_builtins  : ord(i)                         plain:   0.31     psyco: 
0.00     ratio: 116.56
time_builtins  : pow                            plain:   0.35     psyco: 
0.23     ratio:  1.50
time_builtins  : reduce                         plain:   0.73     psyco: 
0.71     ratio:  1.03
time_builtins  : round(f)                       plain:   1.71     psyco: 
0.89     ratio:  1.91
time_builtins  : sums                           plain:   0.18     psyco: 
0.18     ratio:  1.03
time_fib       : matrix                         plain:   0.43     psyco: 
0.36     ratio:  1.19
time_fib       : recursive                      plain:   0.00     psyco: 
0.00     ratio: 19.28
time_fib       : takahashi                      plain:   0.41     psyco: 
0.32     ratio:  1.27
time_generators: send call loop 1000            plain:   2.65     psyco: 
2.94     ratio:  0.90
time_generators: send and loop 1000             plain:   2.95     psyco: 
2.54     ratio:  1.16
time_generators: send just many times           plain:   1.30     psyco: 
0.59     ratio:  2.23
time_generators: iterate just many times        plain:   0.65     psyco: 
0.55     ratio:  1.17
time_generators: call next just many times      plain:   0.92     psyco: 
0.63     ratio:  1.45
time_iter      : iter                           plain:   1.45     psyco: 
0.59     ratio:  2.47
time_math      : floats                         plain:   2.92     psyco: 
1.50     ratio:  1.95
time_properties: method_get                     plain:   0.94     psyco: 
0.12     ratio:  7.88
time_properties: method_set                     plain:   1.01     psyco: 
0.17     ratio:  6.08
time_properties: property_get                   plain:   0.97     psyco: 
0.74     ratio:  1.31
time_properties: property_set                   plain:   1.02     psyco: 
0.92     ratio:  1.12
time_properties: pyproperty_get                 plain:   1.53     psyco: 
1.31     ratio:  1.17
time_properties: pyproperty_set                 plain:   1.02     psyco: 
0.92     ratio:  1.11
time_subdist   : subdist(i)                     plain:   3.65     psyco: 
1.64     ratio:  2.23
time_sums      : rounding                       plain:   0.81     psyco: 
0.79     ratio:  1.03





From Scott.Daniels at Acm.Org  Sat Jul  4 08:28:01 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 05:28:01 -0700
Subject: question of style
In-Reply-To: <687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
Message-ID: <rcCdnXfdkOC51NLXnZ2dnUVZ_s-dnZ2d@pdx.net>

upwestdon wrote:
> if not (self.higher and self.lower):
>     return self.higher or self.lower

     self.lower = 0
     self.higher = 123
     ???
More than just None is False


From Scott.Daniels at Acm.Org  Sat Jul  4 08:31:55 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 05:31:55 -0700
Subject: Reversible Debugging
In-Reply-To: <mailman.2596.1246696386.8015.python-list@python.org>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
	<mailman.2596.1246696386.8015.python-list@python.org>
Message-ID: <rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>

Patrick Sabin wrote:
> Horace Blegg schrieb:
>> You might consider using a VM with 'save-points'. You run the program 
>> (in a debugger/ida/what have you) to a certain point (logical point 
>> would be if/ifelse/else statements, etc) and save the VM state. Once 
>> you've saved, you continue. If you find the path you've taken isn't 
>> what you are after, you can reload a previous save point and start 
>> over, trying a different path the next time.
> That was my idea to implement it. I thought of taking snapshots of the 
> current state every time a "unredoable instruction", e.g random number 
> generation, is done. 
Remember, storing into a location is destruction.
Go over a list of VM instructions and see how many of them are undoable.


From tn.pablo at gmail.com  Sat Jul  4 09:25:39 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sat, 4 Jul 2009 08:25:39 -0500
Subject: Calling C or C++ Functions inside Python script
In-Reply-To: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
References: <a4bf56b0907040306k5770e548r9b4a05efc1ca427f@mail.gmail.com>
Message-ID: <fdd00b510907040625s67a58c42ndb03d7c014457dac@mail.gmail.com>

On Sat, Jul 4, 2009 at 05:06, Parikshat Dubey<parikshatdubey at gmail.com> wrote:
> Hi,
>
> Is this possible to call C functions(inbuilt or user defined) inside python
> script.If yes, please illustrate how it can be done.
> Thanks,
> Parikshat Dubey

>From http://www.swig.org  :

"SWIG is a software development tool that connects programs written in C
and C++ with a variety of high-level programming languages. SWIG is used
with different types of languages including common scripting languages
such as Perl, PHP, Python, Tcl and Ruby. "


---
Pablo Torres N.


From http  Sat Jul  4 09:29:09 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 06:29:09 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<h2mmt2$48p$1@panix3.panix.com>
Message-ID: <7xws6oa862.fsf@ruckus.brouhaha.com>

aahz at pythoncraft.com (Aahz) writes:
> AFAICT, in order for Maybe and Option to work, you need to have some
> kind of static typing system.  Am I missing something?

I'm not sure.  Maybe there could be some kind of syntactic support in
a dynamic language (not that I'm suggesting adding that to Python).
I've been meaning to look up how Erlang does it.  For the limited
purpose of regexps that might or might not match, Perl has some
special support.

A kludgy Python counterpart to Option might be to use a pair (present, x)
where present is a bool saying whether the value is available.  If
present is True, then x is the value.  That could make it harder to
forget to test the flag before using the value.

In the stuff I'm doing, I often find it best to just use a list value,
so instead of:

     y = f(x) if x is not None else None

I can just write

     y = map(f, x)

In many cases it later turns out that list really was the natural
representation and it ends up growing additional potential elements.
I saw some article about database design recently that claimed as a
program evolves, all relationships end up becoming many-to-many.  It
gave as an example, if your program deals with names and addresses, it
will eventually have to handle the case where someone has more than
one residence address.


From davea at ieee.org  Sat Jul  4 09:31:44 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 09:31:44 -0400
Subject: question of style
In-Reply-To: <687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
Message-ID: <4A4F59C0.8030201@ieee.org>

upwestdon wrote:
> On Jul 2, 1:23 pm, Simon Forman <sajmik... at gmail.com> wrote:
>   
>> Hey I was hoping to get your opinions on a sort of minor stylistic
>> point.
>> These two snippets of code are functionally identical. Which would you
>> use and why?
>> The first one is easier [for me anyway] to read and understand, but
>> slightly less efficient, while the second is [marginally] harder to
>> follow but more efficient.
>>
>> ## First snippet
>>
>> if self.higher is self.lower is None: return
>> if self.lower is None: return self.higher
>> if self.higher is None: return self.lower
>>
>> ## Second snippet
>>
>> if self.higher is None:
>>     if self.lower is None:
>>         return
>>     return self.lower
>> if self.lower is None:
>>     return self.higher
>>
>> What do you think?
>>
>> (One minor point: in the first snippet, the "is None" in the first
>> line is superfluous in the context in which it will be used, the only
>> time "self.lower is self.higher" will be true is when they are both
>> None.)
>>     
>
> How about just:
>
> if not (self.higher and self.lower):
>     return self.higher or self.lower
>
>   
But if self.higher is 0  and self.lower is None, this'll return None, 
which wasn't the original intent.

Without having some documented constraints on the self.higher and lower 
types and values, it's difficult to simplify further.



From neilcrighton at gmail.com  Sat Jul  4 09:39:41 2009
From: neilcrighton at gmail.com (Neil Crighton)
Date: Sat, 4 Jul 2009 13:39:41 +0000 (UTC)
Subject: finding most common elements between thousands of multiple arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <loom.20090704T132837-496@post.gmane.org>

You can join all your arrays into a single big array with concatenate.

>>> import numpy as np
>>> a = np.concatenate(array_of_arrays)

Then count the number of occurrances of each unique element using this trick
with searchsorted. This should be pretty fast.

>>> a.sort()
>>> unique_a = np.unique(a)
>>> count = []
>>> for val in unique_a:
...     count.append(a.searchsorted(val,side='right') - a.searchsorted(val,
side='left'))
>>> mostcommonvals = unique_a[np.argsort(count)[-25:]]


Neil



From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 09:42:06 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 13:42:06 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
Message-ID: <025f4dbf$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:

> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>> Currently I need to find the most common elements in thousands of
>>> arrays within one large array (arround 2 million instances with ~70k
>>> unique elements)
...
>> There's no better algorithm for the general case. No method of checking
>> the matrices using less than 2000000-x look-ups will ensure you that
>> there's not a new value with x occurences lurking somewhere.
> 
> Try flattening the arrays into a single large array & sorting it. Then
> you can just iterate over the large array counting as you go; you only
> ever have to insert into the dict once for each value and there's no
> lookups in the dict.

You're suggesting to do a whole bunch of work copying 2,000,000 pointers 
into a single array, then a whole bunch of more work sorting that second 
array (which is O(N*log N) on average), and then finally iterate over the 
second array. Sure, that last step will on average involve fewer than 
O(N) steps, but to get to that point you've already done more work than 
just iterating over the array-of-arrays in the first place.

Now, if you're really lucky, your strategy can be done in fast C code 
instead of slow Python code, and you might see a speed-up for values of N 
which aren't too big. But I wouldn't put money on it.

Another strategy might be to pre-count elements in each array, as you 
build or modify them. This will marginally slow down each modification 
you make to the array, but the payback will be that finding the frequency 
of any element will be almost instantaneous.


-- 
Steven


From davea at ieee.org  Sat Jul  4 09:58:39 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 09:58:39 -0400
Subject: Reversible Debugging
In-Reply-To: <rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>
	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
Message-ID: <4A4F600F.8040402@ieee.org>



Scott David Daniels wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Patrick 
> Sabin wrote:
>> Horace Blegg schrieb:
>>> You might consider using a VM with 'save-points'. You run the 
>>> program (in a debugger/ida/what have you) to a certain point 
>>> (logical point would be if/ifelse/else statements, etc) and save the 
>>> VM state. Once you've saved, you continue. If you find the path 
>>> you've taken isn't what you are after, you can reload a previous 
>>> save point and start over, trying a different path the next time.
>> That was my idea to implement it. I thought of taking snapshots of 
>> the current state every time a "unredoable instruction", e.g random 
>> number generation, is done. 
> Remember, storing into a location is destruction.
> Go over a list of VM instructions and see how many of them are undoable.
>
> </div>
>
>
Read his suggested approach more carefully.  He's not "undoing" 
anything.  He's rolling back to the save-point, and then stepping 
forward to the desired spot.  Except for influences outside his control 
(eg. file system operations), this approach has to work.  Even random 
will work the same, if the generator uses only data that was restored 
from the save-point.  A typical pseudo-random generator works from a 
seed, and if the seed is restored as part of rolling back, he's fine.  
If the snapshot is done via VMWare (for example), he's even okay for 
file operations, except for network and VM-shared files.

"I thought of taking snapshots of the current state every time a 
"unredoable instruction", e.g random number generation, is done.  For 
every other instruction I count the number of instructions done since 
the last snapshot. So I can go back one instruction by restoring to the 
previous state and go the number of instructions minus one forward."

DaveA



From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 10:10:01 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 14:10:01 GMT
Subject: Reversible Debugging
References: <4A4E4B8B.7090104@gmail.com>
	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
	<mailman.2596.1246696386.8015.python-list@python.org>
	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
	<mailman.2610.1246715935.8015.python-list@python.org>
Message-ID: <025f544a$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 09:58:39 -0400, Dave Angel wrote:

> Read his suggested approach more carefully.  He's not "undoing"
> anything.  He's rolling back to the save-point, and then stepping
> forward to the desired spot.  Except for influences outside his control
> (eg. file system operations), this approach has to work.

Is that anything like saying "Except for all the diseases this drug won't 
cure, it cures everything"?

*wink*


-- 
Steven


From Scott.Daniels at Acm.Org  Sat Jul  4 10:19:48 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 07:19:48 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <mailman.2602.1246701345.8015.python-list@python.org>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
Message-ID: <5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>

Vilya Harvey wrote:
> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>> Currently I need to find the most common elements in thousands of
>>> arrays within one large array (arround 2 million instances with ~70k
>>> unique elements)...
> Try flattening the arrays into a single large array & sorting it. Then
> you can just iterate over the large array counting as you go; you only
> ever have to insert into the dict once for each value and there's no
> lookups in the dict....

Actually the next step is to maintain a min-heap as you run down the
sorted array.  Something like:

import numpy as np
import heapq


def frequency(arr):
     '''Generate frequency-value pairs from a numpy array'''
     clustered = arr.flatten() # copy (so can safely sort)
     clustered.sort() # Bring identical values together
     scanner = iter(clustered)
     last = scanner.next()
     count = 1
     for el in scanner:
         if el == last:
             count += 1
         else:
             yield count, last
             last = el
             count = 1
     yield count, last


def most_frequent(arr, N):
     '''Return the top N (freq, val) elements in arr'''
     counted = frequency(arr) # get an iterator for freq-val pairs
     heap = []
     # First, just fill up the array with the first N distinct
     for i in range(N):
         try:
             heap.append(counted.next())
         except StopIteration:
             break # If we run out here, no need for a heap
     else:
         # more to go, switch to a min-heap, and replace the least
         # element every time we find something better
         heapq.heapify(heap)
         for pair in counted:
             if pair > heap[0]:
                 heapq.heapreplace(heap, pair)
     return sorted(heap, reverse=True) # put most frequent first.


--Scott David Daniels
Scott.Daniels at Acm.Org


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 10:38:52 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 04 Jul 2009 14:38:52 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <025f5b0d$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 13:42:06 +0000, Steven D'Aprano wrote:

> On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:
> 
>> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>>> Currently I need to find the most common elements in thousands of
>>>> arrays within one large array (arround 2 million instances with ~70k
>>>> unique elements)
> ...
>>> There's no better algorithm for the general case. No method of
>>> checking the matrices using less than 2000000-x look-ups will ensure
>>> you that there's not a new value with x occurences lurking somewhere.
>> 
>> Try flattening the arrays into a single large array & sorting it. Then
>> you can just iterate over the large array counting as you go; you only
>> ever have to insert into the dict once for each value and there's no
>> lookups in the dict.
> 
> You're suggesting to do a whole bunch of work copying 2,000,000 pointers
> into a single array, then a whole bunch of more work sorting that second
> array (which is O(N*log N) on average), and then finally iterate over
> the second array. Sure, that last step will on average involve fewer
> than O(N) steps, 

Er what?

Ignore that last comment -- I don't know what I was thinking. You still 
have to iterate over all N elements, sorted or not.

> but to get to that point you've already done more work
> than just iterating over the array-of-arrays in the first place.

What it does buy you though, as you pointed out, is reducing the number 
of explicit dict lookups and writes. However, dict lookups and writes are 
very fast, fast enough that they're used throughout Python. A line like:

count += 1

actually is a dict lookup and write.



-- 
Steven


From sajmikins at gmail.com  Sat Jul  4 10:54:38 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sat, 4 Jul 2009 07:54:38 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
Message-ID: <069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>

On Jul 4, 2:03?am, upwestdon <upwest... at gmail.com> wrote:
> On Jul 2, 1:23?pm, Simon Forman <sajmik... at gmail.com> wrote:
>
>
>
> > Hey I was hoping to get your opinions on a sort of minor stylistic
> > point.
> > These two snippets of code are functionally identical. Which would you
> > use and why?
> > The first one is easier [for me anyway] to read and understand, but
> > slightly less efficient, while the second is [marginally] harder to
> > follow but more efficient.
>
> > ## First snippet
>
> > if self.higher is self.lower is None: return
> > if self.lower is None: return self.higher
> > if self.higher is None: return self.lower
>
> > ## Second snippet
>
> > if self.higher is None:
> > ? ? if self.lower is None:
> > ? ? ? ? return
> > ? ? return self.lower
> > if self.lower is None:
> > ? ? return self.higher
>
> > What do you think?
>
> > (One minor point: in the first snippet, the "is None" in the first
> > line is superfluous in the context in which it will be used, the only
> > time "self.lower is self.higher" will be true is when they are both
> > None.)
>
> How about just:
>
> if not (self.higher and self.lower):
> ? ? return self.higher or self.lower

That would work too in this case, both higher and lower are expected
to be either None or an object (that doesn't override the default all-
objects-are-true rule.)

Thanks,
~Simon


From no.email at please.post  Sat Jul  4 11:00:00 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 15:00:00 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
Message-ID: <h2nqpf$d91$1@reader1.panix.com>

In <7xk52p4tgg.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

>kj <no.email at please.post> writes:
>>     sense = cmp(func(hi), func(lo))
>>     if sense == 0:
>>         return None
>>     target_plus = sense * target + epsilon
>>     target_minus = sense * target - epsilon
>>     ...

>The code looks confusing to me and in some sense incorrect.  Suppose
>func(hi)==func(lo)==target.

In hindsight, I too think that it is incorrect, but for a different
reason.  I've rewritten it like this:

    sense = cmp(func(hi), func(lo))
    assert sense != 0, "func is not strictly monotonic in [lo, hi]"

I regard the very special case of func(hi)==func(lo)==target as
pathological (analogous to the fact that a stopped watch is "exactly
right" twice a day), and not one I care to support.

Thanks for your feedback!

kj


From Scott.Daniels at Acm.Org  Sat Jul  4 11:03:39 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 08:03:39 -0700
Subject: Reversible Debugging
In-Reply-To: <mailman.2610.1246715935.8015.python-list@python.org>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
	<mailman.2610.1246715935.8015.python-list@python.org>
Message-ID: <AJ6dnQT3dIoC8NLXnZ2dnUVZ_radnZ2d@pdx.net>

Dave Angel wrote:
> Scott David Daniels wrote:
>> Patrick Sabin wrote:
>>> Horace Blegg schrieb:
>>>> You might consider using a VM with 'save-points'. You run the 
>>>> program (in a debugger/ida/what have you) to a certain point 
>>>> (logical point would be if/ifelse/else statements, etc) and save the 
>>>> VM state. Once you've saved, you continue. If you find the path 
>>>> you've taken isn't what you are after, you can reload a previous 
>>>> save point and start over, trying a different path the next time.
>>> That was my idea to implement it. I thought of taking snapshots of 
>>> the current state every time a "unredoable instruction", e.g random 
>>> number generation, is done. 
>> Remember, storing into a location is destruction.
>> Go over a list of VM instructions and see how many of them are undoable.
> Read his suggested approach more carefully.  He's not "undoing" 
> anything.  He's rolling back to the save-point, and then stepping 
> forward to the desired spot.  
Right, I did misread "unredoable" as "undoable."  However, I suspect a
surprising amount of stuff is "unredoable" -- iff the random number
generator counts as one of those things.  The random number seeder is
unredoable with empty args, but running the generator once seeded is
predictable (by design).  If you don't capture the random number state
as part of your "snapshot," _lots_ of C space storage will be in the
same class, and you are stuck finding the exceptional "safe to use"
cases, rather than the exceptional "unsafe to use."  Similarly, system
calls about time or _any_ callback (when and where executed) create
snapshot points, and I suspect roll forwards will be relatively short.
In fact, in some sense the _lack_ of a callback is unredoable.

--Scott David Daniels
Scott.Daniels at Acm.Org


From no.email at please.post  Sat Jul  4 11:05:48 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 15:05:48 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
Message-ID: <h2nr4c$d91$2@reader1.panix.com>

In <zxr3m.613$P5.65 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:

>> In <mGo3m.591$P5.76 at nwrddc02.gnilink.net> Alan G Isaac <alan.isaac at gmail.com> writes:
>>> 1. Don't use assertions to test argument values!


>On 7/3/2009 12:19 PM kj apparently wrote:
>> Out of curiosity, where does this come from? 


>http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_stmt
>"The current code generator emits no code for an assert statement when optimization is requested at compile time."

Sorry, this doesn't say anything like "don't use assertions to test
argument values".  I'm aware of the fact that assertions are silenced
under certain circumstances.  But where does the principle 1. in
your first reply come from?  I've never seen it before, and would
like to understand the reasoning behind it.

kj


From vinay_sajip at yahoo.co.uk  Sat Jul  4 11:12:36 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Sat, 4 Jul 2009 08:12:36 -0700 (PDT)
Subject: ANN: A new version of the Python module which wraps GnuPG has been 
	released.
Message-ID: <mailman.2635.1246798963.8015.python-announce-list@python.org>

A new version of the Python module which wraps GnuPG has been
released.

What Does It Do?
================
The gnupg module allows Python programs to make use of the
functionality provided by the Gnu Privacy Guard (abbreviated GPG or
GnuPG). Using this module, Python programs can encrypt and decrypt
data, digitally sign documents and verify digital signatures, manage
(generate, list and delete) encryption keys, using proven Public Key
Infrastructure (PKI) encryption technology based on OpenPGP.

This module is expected to be used with Python versions >= 2.4, as it
makes use of the subprocess module which appeared in that version of
Python. Development and testing has been carried out on Windows and
Ubuntu. This module is a newer version derived from earlier work by
Andrew Kuchling, Richard Jones and Steve Traugott.

A test suite using unittest is included with the source distribution.

Simple usage:

>>> import gnupg
>>> gpg = gnupg.GPG(gnupghome='/path/to/keyring/directory')
>>> gpg.list_keys()
[{
  ...
  'fingerprint': 'F819EE7705497D73E3CCEE65197D5DAC68F1AAB2',
  'keyid': '197D5DAC68F1AAB2',
  'length': '1024',
  'type': 'pub',
  'uids': ['', 'Gary Gross (A test user) <gary.gross at gamma.com>']},
 {
  ...
  'fingerprint': '37F24DD4B918CC264D4F31D60C5FEFA7A921FC4A',
  'keyid': '0C5FEFA7A921FC4A',
  'length': '1024',
  ...
  'uids': ['', 'Danny Davis (A test user) <danny.davis at delta.com>']}]
>>> encrypted = gpg.encrypt("Hello, world!", ['0C5FEFA7A921FC4A'])
>>> str(encrypted)
'-----BEGIN PGP MESSAGE-----\nVersion: GnuPG v1.4.9 (GNU/Linux)\n
\nhQIOA/6NHMDTXUwcEAf
...
-----END PGP MESSAGE-----\n'
>>> decrypted = gpg.decrypt(str(encrypted), passphrase='secret')
>>> str(decrypted)
'Hello, world!'
>>> signed = gpg.sign("Goodbye, world!", passphrase='secret')
>>> verified = verified = gpg.verify(str(signed))
>>> print "Verified" if verified else "Not verified"
'Verified'

For more information, visit http://code.google.com/p/python-gnupg/ -
as always, your feedback is most welcome (especially bug reports,
patches and suggestions for improvement). Enjoy!

Cheers

Vinay Sajip
Red Dove Consultants Ltd.


From asm198 at gmail.com  Sat Jul  4 11:23:33 2009
From: asm198 at gmail.com (Icarus)
Date: Sat, 4 Jul 2009 08:23:33 -0700 (PDT)
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
	<h2n3d8$kvq$00$1@news.t-online.com>
Message-ID: <c46b4e76-2c0d-49b5-bb97-c7e38934ac46@y7g2000yqa.googlegroups.com>

On Jul 4, 3:21?am, Peter Otten <__pete... at web.de> wrote:
> Icarus wrote:
> > I'm working on a serial protocol analyzer in python. ?We have an
> > application written by someone else in MFC but we need something that
> > is cross platform. ?I intended to implement the GUI portion in Tkinter
> > but am having trouble.
>
> > The idea is that I will read messages from the serial port and output
> > them to a Tkinter Text object initially. ?Eventually it will have
> > other functionality but that's it for the short term. ?I've written
> > this little test app to experiment with putting things on the GUI via
> > a Queue which is polled by the Tkinter loop.
>
> > On some machines this code works fine and I get whatever I type in
> > displayed in the Text widget. ?On others I get errors like this as
> > soon as I start it running.
>
> > error in background error handler:
> > out of stack space (infinite loop?)
> > ? ? while executing
> > "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> > 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
> > ? ? while execu..."
>
> > I don't understand why on some machines it works exactly as expected
> > and on others it acts the same way Tkinter does when I call functions
> > directly from outside the Tkinter thread. ?Does anyone have any
> > suggestions? ?The full code as appended below. ?Thanks in advance.
>
> > [code]
>
> > import Queue
>
> > class functionQueue:
>
> > ? ? def __init__(self, root = None, timeout = 250):
>
> > ? ? ? ? self.functionQueue = Queue.Queue()
> > ? ? ? ? self.root = root
> > ? ? ? ? self.timeout = timeout
>
> > ? ? ? ? if(self.root):
> > ? ? ? ? ? ? self.pop_function(root)
>
> > ? ? def pop_function(self, root = None):
>
> > ? ? ? ? try:
> > ? ? ? ? ? ? funcArgList = self.functionQueue.get(block = False)
> > ? ? ? ? except Queue.Empty:
> > ? ? ? ? ? ? pass
> > ? ? ? ? else:
> > ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? funcArgList[0](*funcArgList[1])
> > ? ? ? ? ? ? except:
> > ? ? ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? ? ? print "Failed to call function", funcArgList[0]
> > ? ? ? ? ? ? ? ? except:
> > ? ? ? ? ? ? ? ? ? ? print "Failed to call function"
>
> > ? ? ? ? if(root):
> > ? ? ? ? ? ? root.after(self.timeout, lambda: self.pop_function
> > (self.root))
>
> > ? ? def add_function(self, function, argList):
>
> > ? ? ? ? try:
> > ? ? ? ? ? ? self.functionQueue.put([function, argList])
> > ? ? ? ? except:
> > ? ? ? ? ? ? pass
>
> > if( __name__ == '__main__'):
>
> > ? ? import Tkinter
> > ? ? import thread
>
> > ? ? text = Tkinter.Text()
> > ? ? text.pack()
>
> > ? ? myQueue = functionQueue(text, 50)
>
> > ? ? def gui_loop():
> > ? ? ? ? try:
> > ? ? ? ? ? ? text.mainloop()
> > ? ? ? ? except:
> > ? ? ? ? ? ? import os
> > ? ? ? ? ? ? os._exit(1)
>
> > ? ? thread.start_new_thread(text.mainloop, ())
>
> > ? ? while(True):
> > ? ? ? ? usrInput = raw_input()
>
> > ? ? ? ? if(usrInput == "-1"):
> > ? ? ? ? ? ? import os
> > ? ? ? ? ? ? os._exit(0)
>
> > ? ? ? ? myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> > ? ? ? ? myQueue.add_function(text.see, ['end'])
>
> > [/code]
>
> I can make it work over here by putting the UI into the main thread, as
> suggested byhttp://effbot.org/zone/tkinter-threads.htm:
>
> import Queue
> import Tkinter
> import threading
>
> class FunctionQueue:
> ? ? # unchanged
>
> def input_loop():
> ? ? while True:
> ? ? ? ? try:
> ? ? ? ? ? ? usrInput = raw_input()
> ? ? ? ? except EOFError:
> ? ? ? ? ? ? break
> ? ? ? ? myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> ? ? ? ? myQueue.add_function(text.see, ['end'])
> ? ? myQueue.add_function(text.quit, [])
>
> if __name__ == '__main__':
> ? ? text = Tkinter.Text()
> ? ? text.pack()
>
> ? ? myQueue = FunctionQueue(text, 50)
> ? ? threading.Thread(target=input_loop).start()
> ? ? text.mainloop()
>
> Peter

Peter, thanks for the suggestion.  I tried your code exactly on my box
and I still get the same results.  As soon as I run the script and
every time I click on the Text box I get tcl::Bgerror ... just like I
mentioned above.  I'm fairly certain that I'm not calling Tkinter
functions from any other thread but it's acting as though I am as soon
as I create the input thread.
If I comment out the input loop thread everything is fine but of
course that's not terribly useful as a logging box.


From tn.pablo at gmail.com  Sat Jul  4 11:26:15 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sat, 4 Jul 2009 10:26:15 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2nr4c$d91$2@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
Message-ID: <fdd00b510907040826k18cd4ffena72a6c9ce7601a48@mail.gmail.com>

On Sat, Jul 4, 2009 at 10:05, kj<no.email at please.post> wrote:
>>http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_stmt
>>"The current code generator emits no code for an assert statement when optimization is requested at compile time."
>
> Sorry, this doesn't say anything like "don't use assertions to test
> argument values". ?I'm aware of the fact that assertions are silenced
> under certain circumstances. ?But where does the principle 1. in
> your first reply come from? ?I've never seen it before, and would
> like to understand the reasoning behind it.
>
> kj
> --
> http://mail.python.org/mailman/listinfo/python-list
>

But...if no code is generated for assertions on some occasions, then the
parameters would go unchecked, potentially breaking your code in said
occasions.

-- 
Pablo Torres N.


From aahz at pythoncraft.com  Sat Jul  4 11:48:21 2009
From: aahz at pythoncraft.com (Aahz)
Date: 4 Jul 2009 08:48:21 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<h2mmt2$48p$1@panix3.panix.com>
	<7xws6oa862.fsf@ruckus.brouhaha.com>
Message-ID: <h2ntk5$rgh$1@panix3.panix.com>

In article <7xws6oa862.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>
>In many cases it later turns out that list really was the natural
>representation and it ends up growing additional potential elements.
>I saw some article about database design recently that claimed as a
>program evolves, all relationships end up becoming many-to-many.  It
>gave as an example, if your program deals with names and addresses, it
>will eventually have to handle the case where someone has more than
>one residence address.

That's definitely a critical point, and I absolutely agree that this
should get rubbed into people's faces.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From dw at botanicus.net  Sat Jul  4 11:50:56 2009
From: dw at botanicus.net (David Wilson)
Date: Sat, 4 Jul 2009 08:50:56 -0700 (PDT)
Subject: Where does setuptools live?
Message-ID: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>

I'm trying to create a patch for a diabolical issue I keep running
into, but I can't seem to find the setuptools repository. Is it this
one?

    http://svn.python.org/view/sandbox/trunk/setuptools/

It's seen no changes in 9 months.

The issue in question is its (ab)use of .svn to directly read working
copy information rather than going via the well designed 'svn info --
xml' route, which if done, wouldn't result in setuptools busting every
few years, nor require me to downgrade my Subversion installation (OS
X packages don't support multiple versions installed at a time),
checkout a source tree, use setuptools, then re-upgrade so I can go
back to using my other trees.


David


From davea at ieee.org  Sat Jul  4 12:09:34 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 12:09:34 -0400
Subject: Reversible Debugging
In-Reply-To: <025f544a$0$20657$c3e8da3@news.astraweb.com>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>	<mailman.2610.1246715935.8015.python-list@python.org>
	<025f544a$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <4A4F7EBE.4030004@ieee.org>



Steven D'Aprano wrote:
> On Sat, 04 Jul 2009 09:58:39 -0400, Dave Angel wrote:
>
>   
>> Read his suggested approach more carefully.  He's not "undoing"
>> anything.  He's rolling back to the save-point, and then stepping
>> forward to the desired spot.  Except for influences outside his control
>> (eg. file system operations), this approach has to work.
>>     
>
> Is that anything like saying "Except for all the diseases this drug won't 
> cure, it cures everything"?
>
> *wink*
>
>
>   
<grin>
Yeah, pretty close.  That's the problem with speaking in concepts, 
rather than something concrete.

Somebody else brought up VM, but that has two meanings these days.  The 
sense I took it (with regard to save-point) was a program like VMWare, 
where it virtualizes the entire machine.  So any program that deals only 
with the local machine will fit that approach.  And yes, I know there 
are subtleties beyond networks and virtual networks, like time.  When 
you roll the VM back, the time magically stays current.  But for a 
program that deals only with its own process, that tends to just look 
like some other process suddenly hogged the CPU.

Now, if the snapshot is a feature of the Python VM, that's another 
matter entirely.



From amrita at iisermohali.ac.in  Sat Jul  4 12:21:12 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 4 Jul 2009 21:51:12 +0530 (IST)
Subject: mail
Message-ID: <22154.210.212.36.65.1246724472.squirrel@www.iisermohali.ac.in>

Hi,

I want to know that whether using python programming is it possible to
extract chemical shift information about some amino acids of some protein
from BMRB(BioMagResBank) or Ref-DB(referenced databank) or not.

Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From hanooter at gmail.com  Sat Jul  4 12:22:48 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 09:22:48 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com> 
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>

OK then. I will try some of the strategies here but I guess things
arent looking too good. I need to run this over a dataset that someone
pickled. I need to run this 480,000 times so you can see my
frustration. So it doesn't need to be "real time" but it would be nice
it was done sorting this month.

Is there a "bet guess" strategy where it is not 100% accurate but much
faster?

On Jul 4, 7:38?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Sat, 04 Jul 2009 13:42:06 +0000, Steven D'Aprano wrote:
> > On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:
>
> >> 2009/7/4 Andre Engels <andreeng... at gmail.com>:
> >>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanoo... at gmail.com> wrote:
> >>>> Currently I need to find the most common elements in thousands of
> >>>> arrays within one large array (arround 2 million instances with ~70k
> >>>> unique elements)
> > ...
> >>> There's no better algorithm for the general case. No method of
> >>> checking the matrices using less than 2000000-x look-ups will ensure
> >>> you that there's not a new value with x occurences lurking somewhere.
>
> >> Try flattening the arrays into a single large array & sorting it. Then
> >> you can just iterate over the large array counting as you go; you only
> >> ever have to insert into the dict once for each value and there's no
> >> lookups in the dict.
>
> > You're suggesting to do a whole bunch of work copying 2,000,000 pointers
> > into a single array, then a whole bunch of more work sorting that second
> > array (which is O(N*log N) on average), and then finally iterate over
> > the second array. Sure, that last step will on average involve fewer
> > than O(N) steps,
>
> Er what?
>
> Ignore that last comment -- I don't know what I was thinking. You still
> have to iterate over all N elements, sorted or not.
>
> > but to get to that point you've already done more work
> > than just iterating over the array-of-arrays in the first place.
>
> What it does buy you though, as you pointed out, is reducing the number
> of explicit dict lookups and writes. However, dict lookups and writes are
> very fast, fast enough that they're used throughout Python. A line like:
>
> count += 1
>
> actually is a dict lookup and write.
>
> --
> Steven



From __peter__ at web.de  Sat Jul  4 12:24:06 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 04 Jul 2009 18:24:06 +0200
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
	<h2n3d8$kvq$00$1@news.t-online.com>
	<c46b4e76-2c0d-49b5-bb97-c7e38934ac46@y7g2000yqa.googlegroups.com>
Message-ID: <h2nvmi$9oh$03$1@news.t-online.com>

Icarus wrote:

> On Jul 4, 3:21 am, Peter Otten <__pete... at web.de> wrote:
>> Icarus wrote:
>> > I'm working on a serial protocol analyzer in python.  We have an
>> > application written by someone else in MFC but we need something that
>> > is cross platform.  I intended to implement the GUI portion in Tkinter
>> > but am having trouble.
>>
>> > The idea is that I will read messages from the serial port and output
>> > them to a Tkinter Text object initially.  Eventually it will have
>> > other functionality but that's it for the short term.  I've written
>> > this little test app to experiment with putting things on the GUI via
>> > a Queue which is polled by the Tkinter loop.
>>
>> > On some machines this code works fine and I get whatever I type in
>> > displayed in the Text widget.  On others I get errors like this as
>> > soon as I start it running.
>>
>> > error in background error handler:
>> > out of stack space (infinite loop?)
>> > while executing
>> > "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
>> > 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
>> > while execu..."
>>
>> > I don't understand why on some machines it works exactly as expected
>> > and on others it acts the same way Tkinter does when I call functions
>> > directly from outside the Tkinter thread.  Does anyone have any
>> > suggestions?  The full code as appended below.  Thanks in advance.
>>
>> > [code]
>>
>> > import Queue
>>
>> > class functionQueue:
>>
>> > def __init__(self, root = None, timeout = 250):
>>
>> > self.functionQueue = Queue.Queue()
>> > self.root = root
>> > self.timeout = timeout
>>
>> > if(self.root):
>> > self.pop_function(root)
>>
>> > def pop_function(self, root = None):
>>
>> > try:
>> > funcArgList = self.functionQueue.get(block = False)
>> > except Queue.Empty:
>> > pass
>> > else:
>> > try:
>> > funcArgList[0](*funcArgList[1])
>> > except:
>> > try:
>> > print "Failed to call function", funcArgList[0]
>> > except:
>> > print "Failed to call function"
>>
>> > if(root):
>> > root.after(self.timeout, lambda: self.pop_function
>> > (self.root))
>>
>> > def add_function(self, function, argList):
>>
>> > try:
>> > self.functionQueue.put([function, argList])
>> > except:
>> > pass
>>
>> > if( __name__ == '__main__'):
>>
>> > import Tkinter
>> > import thread
>>
>> > text = Tkinter.Text()
>> > text.pack()
>>
>> > myQueue = functionQueue(text, 50)
>>
>> > def gui_loop():
>> > try:
>> > text.mainloop()
>> > except:
>> > import os
>> > os._exit(1)
>>
>> > thread.start_new_thread(text.mainloop, ())
>>
>> > while(True):
>> > usrInput = raw_input()
>>
>> > if(usrInput == "-1"):
>> > import os
>> > os._exit(0)
>>
>> > myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>> > myQueue.add_function(text.see, ['end'])
>>
>> > [/code]
>>
>> I can make it work over here by putting the UI into the main thread, as
>> suggested byhttp://effbot.org/zone/tkinter-threads.htm:
>>
>> import Queue
>> import Tkinter
>> import threading
>>
>> class FunctionQueue:
>> # unchanged
>>
>> def input_loop():
>> while True:
>> try:
>> usrInput = raw_input()
>> except EOFError:
>> break
>> myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>> myQueue.add_function(text.see, ['end'])
>> myQueue.add_function(text.quit, [])
>>
>> if __name__ == '__main__':
>> text = Tkinter.Text()
>> text.pack()
>>
>> myQueue = FunctionQueue(text, 50)
>> threading.Thread(target=input_loop).start()
>> text.mainloop()
>>
>> Peter
> 
> Peter, thanks for the suggestion.  I tried your code exactly on my box
> and I still get the same results.  As soon as I run the script and
> every time I click on the Text box I get tcl::Bgerror ... just like I
> mentioned above.  I'm fairly certain that I'm not calling Tkinter
> functions from any other thread but it's acting as though I am as soon
> as I create the input thread.
> If I comment out the input loop thread everything is fine but of
> course that's not terribly useful as a logging box.

http://bugs.python.org/issue3835

Could tcl have been built without thread support on the failing machines?

Peter



From no.email at please.post  Sat Jul  4 12:30:10 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 16:30:10 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
Message-ID: <h2o02i$3gs$1@reader1.panix.com>

In <mailman.2611.1246721197.8015.python-list at python.org> "Pablo Torres N." <tn.pablo at gmail.com> writes:

>On Sat, Jul 4, 2009 at 10:05, kj<no.email at please.post> wrote:
>>>http://docs.python.org/reference/simple_stmts.html#grammar-token-assert_s=
>tmt
>>>"The current code generator emits no code for an assert statement when op=
>timization is requested at compile time."
>>
>> Sorry, this doesn't say anything like "don't use assertions to test
>> argument values". =C2=A0I'm aware of the fact that assertions are silence=
>d
>> under certain circumstances. =C2=A0But where does the principle 1. in
>> your first reply come from? =C2=A0I've never seen it before, and would
>> like to understand the reasoning behind it.
>>
>> kj
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>

>But...if no code is generated for assertions on some occasions, then the
>parameters would go unchecked, potentially breaking your code in said
>occasions.

This implies that code that uses *any* assert statement (other than
perhaps the trivial and meaningless ones like "assert True") is
liable to break, because whatever it is that these assert statements
are checking "on some occasions, ... would go unchecked, potentially
breaking your code."

I'm beginning to think that the original "precept" was simply "cargo
cult," i.e. one of those rules that are parroted without being
fully understood.

As I wrote in my original post, the function I posted was an internal
("helper") function, not to be used outside of the file.  This fact
was further (ahem) underscored by the leading underscore in the
function's name.  Under these circumstances, the assert statements
seem to me perfectly in keeping with the intended use for them. 

kj



From floris.bruynooghe at gmail.com  Sat Jul  4 12:35:47 2009
From: floris.bruynooghe at gmail.com (Floris Bruynooghe)
Date: Sat, 4 Jul 2009 09:35:47 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
Message-ID: <3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>

On Jul 4, 4:50?pm, David Wilson <d... at botanicus.net> wrote:
> I'm trying to create a patch for a diabolical issue I keep running
> into, but I can't seem to find the setuptools repository. Is it this
> one?
>
> ? ?http://svn.python.org/view/sandbox/trunk/setuptools/

It is, see
http://mail.python.org/pipermail/distutils-sig/2009-July/012374.html


> It's seen no changes in 9 months.

It's setuptools...  I'm sure you can find many flamefests on distutils-
sig about this.


Regards
Floris


From python at mrabarnett.plus.com  Sat Jul  4 12:40:48 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 04 Jul 2009 17:40:48 +0100
Subject: Problems with using queue in Tkinter application
In-Reply-To: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
Message-ID: <4A4F8610.1080202@mrabarnett.plus.com>

Icarus wrote:
> I'm working on a serial protocol analyzer in python.  We have an
> application written by someone else in MFC but we need something that
> is cross platform.  I intended to implement the GUI portion in Tkinter
> but am having trouble.
> 
> The idea is that I will read messages from the serial port and output
> them to a Tkinter Text object initially.  Eventually it will have
> other functionality but that's it for the short term.  I've written
> this little test app to experiment with putting things on the GUI via
> a Queue which is polled by the Tkinter loop.
> 
> On some machines this code works fine and I get whatever I type in
> displayed in the Text widget.  On others I get errors like this as
> soon as I start it running.
> 
> error in background error handler:
> out of stack space (infinite loop?)
>     while executing
> "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
>     while execu..."
> 
> 
> I don't understand why on some machines it works exactly as expected
> and on others it acts the same way Tkinter does when I call functions
> directly from outside the Tkinter thread.  Does anyone have any
> suggestions?  The full code as appended below.  Thanks in advance.
> 
> [code]
> 
> import Queue
> 
> class functionQueue:
> 
>     def __init__(self, root = None, timeout = 250):
> 
>         self.functionQueue = Queue.Queue()
>         self.root = root
>         self.timeout = timeout
> 
>         if(self.root):
>             self.pop_function(root)
> 
> 
>     def pop_function(self, root = None):
> 
>         try:
>             funcArgList = self.functionQueue.get(block = False)
>         except Queue.Empty:
>             pass
>         else:
>             try:
>                 funcArgList[0](*funcArgList[1])
>             except:
>                 try:
>                     print "Failed to call function", funcArgList[0]
>                 except:
>                     print "Failed to call function"
> 
>         if(root):
>             root.after(self.timeout, lambda: self.pop_function
> (self.root))
> 
>     def add_function(self, function, argList):
> 
>         try:
>             self.functionQueue.put([function, argList])
>         except:
>             pass
> 
> 
> if( __name__ == '__main__'):
> 
>     import Tkinter
>     import thread
> 
>     text = Tkinter.Text()
>     text.pack()
> 
>     myQueue = functionQueue(text, 50)
> 
>     def gui_loop():
>         try:
>             text.mainloop()
>         except:
>             import os
>             os._exit(1)
> 
>     thread.start_new_thread(text.mainloop, ())
> 
>     while(True):
>         usrInput = raw_input()
> 
>         if(usrInput == "-1"):
>             import os
>             os._exit(0)
> 
>         myQueue.add_function(text.insert, ['end', usrInput + "\n"])
>         myQueue.add_function(text.see, ['end'])
> 
> [/code]
> 
Only an idea, but:

     myQueue = functionQueue(text, 50)

runs in the main thread, so the pop_function method is calling Tkinter
methods in the main thread every 50ms.

But:

     thread.start_new_thread(text.mainloop, ())

is running the Tkinter main loop in another thread.

You might be experiencing a race condition, so different timings on
different machines might cause a problem to appear sooner on one than
another.


From fabiofz at gmail.com  Sat Jul  4 13:17:31 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Sat, 4 Jul 2009 14:17:31 -0300
Subject: Python debugger
In-Reply-To: <740981.83964.qm@web7901.mail.in.yahoo.com>
References: <740981.83964.qm@web7901.mail.in.yahoo.com>
Message-ID: <cfb578b20907041017r4a9f0c9td8ead460955edea6@mail.gmail.com>

> Hi,
> Could you suggest some python debuggers?
>
> Thanks,
> Srini


Pydev has a debugger that supports the common debugger features
(watches, multiple threads, breakpoints, conditional breakpoints, step
in, out, etc -- http://fabioz.com/pydev/manual_adv_debugger.html ),
and pydev extensions adds to that a remote debugger (
http://fabioz.com/pydev/manual_adv_remote_debugger.html ) and a
console ( http://fabioz.com/pydev/manual_adv_debug_console.html ).

Cheers,

Fabio


From patrick.just4fun at gmail.com  Sat Jul  4 13:21:14 2009
From: patrick.just4fun at gmail.com (Patrick Sabin)
Date: Sat, 04 Jul 2009 19:21:14 +0200
Subject: Reversible Debugging
In-Reply-To: <4A4F7EBE.4030004@ieee.org>
References: <4A4E4B8B.7090104@gmail.com>	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>	<mailman.2596.1246696386.8015.python-list@python.org>	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>	<mailman.2610.1246715935.8015.python-list@python.org>	<025f544a$0$20657$c3e8da3@news.astraweb.com>
	<4A4F7EBE.4030004@ieee.org>
Message-ID: <4A4F8F8A.4080702@gmail.com>


> Now, if the snapshot is a feature of the Python VM, that's another 
> matter entirely.
I thought of taking a snapshot using fork, which creates a copy of the 
process. It may not be the
most performant, but it should be quite portable. Of course there are 
some issues with
multithreading/multiprocessing.

If someone has another idea of taking a snapshot let me know. Using 
VMWare is not a
very elegant way in my opinion.



From nagle at animats.com  Sat Jul  4 13:33:15 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 04 Jul 2009 10:33:15 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
Message-ID: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>

    As an example of code that really needs to run fast, but is
speed-limited by Python's limitations, see "tokenizer.py" in

	http://code.google.com/p/html5lib/

This is a parser for HTML 5, a piece of code that will be needed
in many places and will process large amounts of data. It's written
entirely in Python.  Take a look at how much work has to be performed
per character.

This is a good test for Python implementation bottlenecks.  Run
that tokenizer on HTML, and see where the time goes.

("It should be written in C" is not an acceptable answer.)

Python doesn't have a "switch" or "case" statement, and when
you need a state machine with many states, that makes for painful,
slow code.  There's a comment in the code that it would be useful
to run a few billion lines of HTML through an instrumented version
of the parser to decide in which order the IF statements should be
executed.  You shouldn't have to do that.

Yes, I've read PEP 3103.  The big problem is the difficulty of figuring
out what's a constant and what might change.  If all the cases are constants,
case statements are easy.  But in Python, the compiler can't tell.

Parsers have many named compile-time constants.  Python doesn't support
named compile-time constants, and this is one of the places where we
have to pay the bill for that limitation.

Something to think about when you need three more racks of servers
because the HTML parser is slow.

				John Nagle


From jeremy.cowles at gmail.com  Sat Jul  4 13:44:57 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Sat, 4 Jul 2009 10:44:57 -0700
Subject: Zipped Python?
Message-ID: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>

Hi all,

I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e. no
install). My intentions are to use it for a distributed computing project
(PyMW) where there is no guarantee that Python is installed on the worker
machines and an interactive install is out of the question.

I've been looking around, but I haven't been able to turn anything useful up
so far. Any help would be appreciated.

--
Jeremy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/b04f1041/attachment-0001.html>

From vilya.harvey at gmail.com  Sat Jul  4 13:53:58 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sat, 4 Jul 2009 18:53:58 +0100
Subject: Reversible Debugging
In-Reply-To: <4A4F8F8A.4080702@gmail.com>
References: <4A4E4B8B.7090104@gmail.com>
	<b78ad4bc0907032346l2fdd1617qc1b6453065d7ab2b@mail.gmail.com>
	<mailman.2596.1246696386.8015.python-list@python.org>
	<rcCdnXbdkOCS19LXnZ2dnUVZ_s-dnZ2d@pdx.net>
	<mailman.2610.1246715935.8015.python-list@python.org>
	<025f544a$0$20657$c3e8da3@news.astraweb.com>
	<4A4F7EBE.4030004@ieee.org> <4A4F8F8A.4080702@gmail.com>
Message-ID: <6aef848f0907041053j24d646a4rd6eca49e44a4b0d7@mail.gmail.com>

2009/7/4 Patrick Sabin <patrick.just4fun at gmail.com>:
> If someone has another idea of taking a snapshot let me know. Using VMWare
> is not a
> very elegant way in my opinion.

Someone implemented the same idea for Java a while ago. They called it
"omniscient debugging"; you can find details at
    http://www.lambdacs.com/debugger/
and a paper about it at
    http://www.lambdacs.com/debugger/AADEBUG_Mar_03.pdf

Another more recent paper on the topic is
    http://scg.unibe.ch/archive/papers/Lien08bBackInTimeDebugging.pdf

I haven't read either of these papers myself, but maybe they'll give
you some ideas.

Vil.


From vilya.harvey at gmail.com  Sat Jul  4 13:59:24 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sat, 4 Jul 2009 18:59:24 +0100
Subject: finding most common elements between thousands of multiple 
	arrays.
In-Reply-To: <025f5b0d$0$20657$c3e8da3@news.astraweb.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <6aef848f0907041059n27f88449v16d5fdb4af5c22d2@mail.gmail.com>

2009/7/4 Steven D'Aprano <steve at remove-this-cybersource.com.au>:
> On Sat, 04 Jul 2009 13:42:06 +0000, Steven D'Aprano wrote:
>
>> On Sat, 04 Jul 2009 10:55:44 +0100, Vilya Harvey wrote:
>>
>>> 2009/7/4 Andre Engels <andreengels at gmail.com>:
>>>> On Sat, Jul 4, 2009 at 9:33 AM, mclovin<hanooter at gmail.com> wrote:
>>>>> Currently I need to find the most common elements in thousands of
>>>>> arrays within one large array (arround 2 million instances with ~70k
>>>>> unique elements)
>> ...
>>>> There's no better algorithm for the general case. No method of
>>>> checking the matrices using less than 2000000-x look-ups will ensure
>>>> you that there's not a new value with x occurences lurking somewhere.
>>>
>>> Try flattening the arrays into a single large array & sorting it. Then
>>> you can just iterate over the large array counting as you go; you only
>>> ever have to insert into the dict once for each value and there's no
>>> lookups in the dict.
>>
>> You're suggesting to do a whole bunch of work copying 2,000,000 pointers
>> into a single array, then a whole bunch of more work sorting that second
>> array (which is O(N*log N) on average), and then finally iterate over
>> the second array. Sure, that last step will on average involve fewer
>> than O(N) steps,
>
> Er what?
>
> Ignore that last comment -- I don't know what I was thinking. You still
> have to iterate over all N elements, sorted or not.
>
>> but to get to that point you've already done more work
>> than just iterating over the array-of-arrays in the first place.
>
> What it does buy you though, as you pointed out, is reducing the number
> of explicit dict lookups and writes. However, dict lookups and writes are
> very fast, fast enough that they're used throughout Python. A line like:
>
> count += 1
>
> actually is a dict lookup and write.

I did some tests, just to be sure, and you're absolutely right: just
creating the flattened list took several hundred (!) times as long as
iterating through all the lists in place. Live and learn...

Vil.


From benjamin.kaplan at case.edu  Sat Jul  4 14:03:52 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Sat, 4 Jul 2009 14:03:52 -0400
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <ec96e1390907041103k6f29b21oe3141d2733de3aca@mail.gmail.com>

On Sat, Jul 4, 2009 at 1:33 PM, John Nagle<nagle at animats.com> wrote:
> ? As an example of code that really needs to run fast, but is
> speed-limited by Python's limitations, see "tokenizer.py" in
>
> ? ? ? ?http://code.google.com/p/html5lib/
>
> This is a parser for HTML 5, a piece of code that will be needed
> in many places and will process large amounts of data. It's written
> entirely in Python. ?Take a look at how much work has to be performed
> per character.
>
> This is a good test for Python implementation bottlenecks. ?Run
> that tokenizer on HTML, and see where the time goes.
>
> ("It should be written in C" is not an acceptable answer.)
>
> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code. ?There's a comment in the code that it would be useful
> to run a few billion lines of HTML through an instrumented version
> of the parser to decide in which order the IF statements should be
> executed. ?You shouldn't have to do that.
>

If you're cases are hashable, just use a dict instead of the if chain.
Then you get the constant time access to it.

def func_a() :
   ...
def func_b():
   ...
def func_c():
   ....

case = {"a":func_a, "b":func_b, "c":func_c}

case[value]()

> Yes, I've read PEP 3103. ?The big problem is the difficulty of figuring
> out what's a constant and what might change. ?If all the cases are
> constants,
> case statements are easy. ?But in Python, the compiler can't tell.
>
> Parsers have many named compile-time constants. ?Python doesn't support
> named compile-time constants, and this is one of the places where we
> have to pay the bill for that limitation.
>
> Something to think about when you need three more racks of servers
> because the HTML parser is slow.
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?John Nagle
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From http  Sat Jul  4 14:10:48 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:10:48 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
Message-ID: <7x8wj4uxnb.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> > if not (self.higher and self.lower):
> > ? ? return self.higher or self.lower
> 
> That would work too in this case, both higher and lower are expected
> to be either None or an object (that doesn't override the default all-
> objects-are-true rule.)

-1.

Objects can support methods like __bool__, __len__ (a tree might use
this to compute the number of nodes or something like that), and
__nonzero__.  If len(object)==0 then the object is treated as false.
So that test can fail if a __len__ method gets added to the tree class
sometime.  Or you might decide you want to support empty trees which
would test as false.

Anyway, Python's overloading of bool(...) is yet another misfeature
and although it's convenient, the "explicit is better than implicit"
principle indicates to avoid that sort of trick.  


From mwilson at the-wire.com  Sat Jul  4 14:20:09 2009
From: mwilson at the-wire.com (Mel)
Date: Sat, 04 Jul 2009 14:20:09 -0400
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <h2o5ml$27qv$1@services.telesweet.net>

John Nagle wrote:
[ ... ]
> Parsers have many named compile-time constants.  Python doesn't support
> named compile-time constants, and this is one of the places where we
> have to pay the bill for that limitation.
> 
> Something to think about when you need three more racks of servers
> because the HTML parser is slow.

One technique used in such a case is to dispatch different case-handling 
functions via a dictionary lookup.

	Mel.




From http  Sat Jul  4 14:20:20 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:20:20 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
Message-ID: <7x4otsux7f.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
>     sense = cmp(func(hi), func(lo))
>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"

bisection search usually just requires the function to be continuous
and to have its value cross the target somewhere between the endpoints,
not be monotonic.

> I regard the very special case of func(hi)==func(lo)==target as
> pathological (analogous to the fact that a stopped watch is "exactly
> right" twice a day), and not one I care to support.

I do think you should support that case, under the "do 'nothing'
gracefully" principle.  Having your equation solver crash if the
equation is already solved is like having your sorting function crash
if the input is already sorted.  E.g. the function should do something
reasonable if you end up calling it twice.


From http  Sat Jul  4 14:29:20 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:29:20 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
Message-ID: <7xzlbkti7z.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
> This implies that code that uses *any* assert statement (other than
> perhaps the trivial and meaningless ones like "assert True") is
> liable to break, because whatever it is that these assert statements
> are checking "on some occasions, ... would go unchecked, potentially
> breaking your code."

Yes, that implication is absolutely valid.  The purpose of assert
statements is to debug the code, by checking for conditions that are
supposed to be impossible.  Unless the program is broken (i.e.  the
impossible happened), no assert statement should ever trigger.

Invalid input data is not considered impossible and doesn't imply a
broken program, so assert statements are not the appropriate way to
check for it.  I like to use a function like

  def check(condition, msg="data error"):
     if not condition: raise ValueError, msg

  ... 
  check (x >= 0, "invalid x")  # raises ValueError if x is negative
  y = sqrt(x)

instead.


From lie.1296 at gmail.com  Sat Jul  4 14:36:38 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sat, 04 Jul 2009 18:36:38 GMT
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
Message-ID: <WiN3m.2614$ze1.857@news-server.bigpond.net.au>

mclovin wrote:
> OK then. I will try some of the strategies here but I guess things
> arent looking too good. I need to run this over a dataset that someone
> pickled. I need to run this 480,000 times so you can see my
> frustration. So it doesn't need to be "real time" but it would be nice
> it was done sorting this month.
> 
> Is there a "bet guess" strategy where it is not 100% accurate but much
> faster?

Heuristics?

If you don't need 100% accuraccy, you can simply sample 10000 or so
element and find the most common element in this small sample space. It
should be much faster, though you'll probably need to determine the best
cutoff number (too small and you're risking biases, too large and it
would be slower). random.sample() might be useful here.


From http  Sat Jul  4 14:40:19 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 11:40:19 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <7xvdm8thpo.fsf@ruckus.brouhaha.com>

John Nagle <nagle at animats.com> writes:
> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code.  ...
> There's a comment in the code that it would be useful
> to run a few billion lines of HTML through an instrumented version
> of the parser to decide in which order the IF statements should be
> executed.  You shouldn't have to do that.

In that particular program it would probably be better to change those
if/elif/elif/else constructs to dictionary lookups.  I see the program
already does that for some large tables.



From python at mrabarnett.plus.com  Sat Jul  4 14:43:24 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 04 Jul 2009 19:43:24 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <7xzlbkti7z.fsf@ruckus.brouhaha.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
Message-ID: <4A4FA2CC.1080105@mrabarnett.plus.com>

Paul Rubin wrote:
> kj <no.email at please.post> writes:
>> This implies that code that uses *any* assert statement (other than
>> perhaps the trivial and meaningless ones like "assert True") is
>> liable to break, because whatever it is that these assert statements
>> are checking "on some occasions, ... would go unchecked, potentially
>> breaking your code."
> 
> Yes, that implication is absolutely valid.  The purpose of assert
> statements is to debug the code, by checking for conditions that are
> supposed to be impossible.  Unless the program is broken (i.e.  the
> impossible happened), no assert statement should ever trigger.
> 
Technically these are known as "invariants". An assertion will always be
True if the program is bug-free, no matter what the user might throw at
it; it's not the same as validation.

> Invalid input data is not considered impossible and doesn't imply a
> broken program, so assert statements are not the appropriate way to
> check for it.  I like to use a function like
> 
>   def check(condition, msg="data error"):
>      if not condition: raise ValueError, msg
> 
>   ... 
>   check (x >= 0, "invalid x")  # raises ValueError if x is negative
>   y = sqrt(x)
> 
> instead.



From alan.isaac at gmail.com  Sat Jul  4 14:54:02 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sat, 04 Jul 2009 18:54:02 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2o02i$3gs$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
Message-ID: <ezN3m.828$P5.11@nwrddc02.gnilink.net>

On 7/4/2009 12:30 PM kj apparently wrote:
> I'm beginning to think that the original "precept" was simply "cargo
> cult," i.e. one of those rules that are parroted without being
> fully understood.


Adopting such a view is of course an alternative to
attempting to understand, but perhaps less useful.

Alan Isaac

PS For additional explanation:
http://java.sun.com/j2se/1.4.2/docs/guide/lang/assert.html


From grante at visi.com  Sat Jul  4 15:15:31 2009
From: grante at visi.com (Grant Edwards)
Date: Sat, 04 Jul 2009 14:15:31 -0500
Subject: mail
References: <mailman.2614.1246725781.8015.python-list@python.org>
Message-ID: <SIGdnTlPq_HON9LXnZ2dnUVZ_tadnZ2d@posted.usinternet>

On 2009-07-04, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:

> I want to know that whether using python programming is it
> possible to extract chemical shift information about some
> amino acids of some protein from BMRB(BioMagResBank) or
> Ref-DB(referenced databank) or not.

Yes.

I don't know how easy it would be, but I'm pretty confident it
is possible.

I'm assuming it is currently possible to do so using some sort
of software.  If it's currently impossible to do so using other
methods (e.g. such information doesn't exist or you don't have
access to the dabases), then using Python isn't going cause any
miracles to happen.

-- 
Grant



From Scott.Daniels at Acm.Org  Sat Jul  4 15:51:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 12:51:58 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
Message-ID: <tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>

mclovin wrote:
> OK then. I will try some of the strategies here but I guess things
> arent looking too good. I need to run this over a dataset that someone
> pickled. I need to run this 480,000 times so you can see my
> frustration. So it doesn't need to be "real time" but it would be nice
> it was done sorting this month.
> 
> Is there a "bet guess" strategy where it is not 100% accurate but much
> faster?

Well, I timed a run of a version of mine, and the scan is approx 5X
longer than the copy-and-sort.  Time arr_of_arr.flatten().sort() to
see how quickly the copy and sort happens.So you could try a variant
exploiting the following property:
     If you know the minimum length of a run that will be in the top 25,
then the value for each of the most-frequent run entries must show up at
positions n * stride and (n + 1) * stride (for some n).  That should
drastically reduce the scan cost, as long as stride is reasonably large.

For my uniformly distributed 0..1024 values in 5M x 5M array,
About 2.5 sec to flatten and sort.
About 15 sec to run one of my heapish thingies.
the least frequency encountered: 24716
so, with stride at

sum(flattened[:-stride:stride] == flattened[stride::stride]) == 1000
So there are only 1000 points to investigate.
With any distribution other than uniform, that should go _way_ down.
So just pull out those points, use bisect to get their frequencies, and 
feed those results into the heap accumulation.

--Scott David Daniels


From Scott.Daniels at Acm.Org  Sat Jul  4 16:01:00 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 13:01:00 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <7xzlbkti7z.fsf@ruckus.brouhaha.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
Message-ID: <zu-dnXX0eefNLtLXnZ2dnUVZ_uWdnZ2d@pdx.net>

Paul Rubin wrote:
> Invalid input data is not considered impossible and doesn't imply a
> broken program, so assert statements are not the appropriate way to
> check for it.  I like to use a function like
> 
>   def check(condition, msg="data error"):
>      if not condition: raise ValueError, msg
> 
>   ... 
>   check (x >= 0, "invalid x")  # raises ValueError if x is negative
>   y = sqrt(x)

And I curse such uses, since I don't get to see the troublesome value,
or why it is troublesome.  In the above case, y = sqrt(x) at least
raises ValueError('math domain error'), which is more information than
you are providing.

How about:

      ...
      if x >= 0: raise ValueError('x = %r not allowed (negative)?' % x)
      ...

--Scott David Daniels
Scott.Daniels at Acm.Org


From sajmikins at gmail.com  Sat Jul  4 16:05:36 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sat, 4 Jul 2009 13:05:36 -0700 (PDT)
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com> 
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com> 
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
Message-ID: <0a175b39-f084-4814-92e0-80b6cfce6130@c36g2000yqn.googlegroups.com>

On Jul 4, 2:10?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Simon Forman <sajmik... at gmail.com> writes:
> > > if not (self.higher and self.lower):
> > > ? ? return self.higher or self.lower
>
> > That would work too in this case, both higher and lower are expected
> > to be either None or an object (that doesn't override the default all-
> > objects-are-true rule.)
>
> -1.

Heh heh heh, I figured someone might call me on this, but I stopped
short of adding further elucidation to that parenthetical clause.

What I meant (of course, *wink*) was "...an instance of a user-defined
class that doesn't override the special double-underscore methods in a
way that causes it (the instance) to be considered False in a 'boolean
context', as they say in perl."

In [1]: class bar: pass
   ...:

In [2]: b = bar()

In [3]: bool(b)
Out[3]: True



> Objects can support methods like __bool__, __len__ (a tree might use
> this to compute the number of nodes or something like that), and
> __nonzero__. ?If len(object)==0 then the object is treated as false.
> So that test can fail if a __len__ method gets added to the tree class
> sometime. ?Or you might decide you want to support empty trees which
> would test as false.

Ya, that's exactly why I stuck to checking explicitly against None in
that tree code. :]


> Anyway, Python's overloading of bool(...) is yet another misfeature
> and although it's convenient, the "explicit is better than implicit"
> principle indicates to avoid that sort of trick. ?

I really like the "misfeature" myself.  Python (to me) seems to
relieve you of gory details that get in the way (compare equivalent C+
+ and Python code) but still exposes you to gory details that, with
care in coding, can make your code easier to grok and more elegant in
general.

BTW, Paul, kind of a tangent: I reimplemented the same algorithm but
using tuples instead of instances (and empty tuples for "NULL"
values.)  I was trying to mess around in the space you seemed to
indicate existed, i.e. a better implementation using other datatypes,
but I didn't have a clear idea what I was doing and, as I said, I
started by simply re-implementing with a different datatype.

Much to my surprise and delight, I discovered the tuple-based BTree
was /already/ a "persistent data type"!  It was both awesome and a bit
of an anti-climax. :]


From http  Sat Jul  4 16:55:04 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 13:55:04 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<zu-dnXX0eefNLtLXnZ2dnUVZ_uWdnZ2d@pdx.net>
Message-ID: <7xbpo0f9sn.fsf@ruckus.brouhaha.com>

Scott David Daniels <Scott.Daniels at Acm.Org> writes:
> And I curse such uses, since I don't get to see the troublesome value,
> or why it is troublesome.  In the above case, y = sqrt(x) at least
> raises ValueError('math domain error'), which is more information than
> you are providing.
>
> How about:
>       if x >= 0: raise ValueError('x = %r not allowed (negative)?' % x)

Better still in these situations is to throw to pdb.
But yes, you can put a formatted string in a check message.


From no.email at please.post  Sat Jul  4 17:10:44 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 21:10:44 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
	<7x4otsux7f.fsf@ruckus.brouhaha.com>
Message-ID: <h2oggj$n9p$1@reader1.panix.com>

In <7x4otsux7f.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

>kj <no.email at please.post> writes:
>>     sense = cmp(func(hi), func(lo))
>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"

>bisection search usually just requires the function to be continuous
>and to have its value cross the target somewhere between the endpoints,
>not be monotonic.

Try the algorithm I posted with lo = -pi/4, hi = 2*pi, func = cos,
target = -1, and see what you get...

>> I regard the very special case of func(hi)==func(lo)==target as
>> pathological (analogous to the fact that a stopped watch is "exactly
>> right" twice a day), and not one I care to support.

>I do think you should support that case, under the "do 'nothing'
>gracefully" principle.

You keep missing the point that this is an *internal* *helper*
*convenience* function, meant to abstract away common logic from
a handful of places and thus eliminate some code repetition within
a module.  It is *not* a library function intended to be called
from elsewhere.  So talk of "supporting" anything is besides the
point.  Any internal use of this function that applies it to a
non-strictly-monotonic function is, by assumption, an error.

kj


From no.email at please.post  Sat Jul  4 17:13:23 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 21:13:23 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
Message-ID: <h2ogli$n9p$2@reader1.panix.com>

In <7xzlbkti7z.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

>kj <no.email at please.post> writes:
>> This implies that code that uses *any* assert statement (other than
>> perhaps the trivial and meaningless ones like "assert True") is
>> liable to break, because whatever it is that these assert statements
>> are checking "on some occasions, ... would go unchecked, potentially
>> breaking your code."

>Yes, that implication is absolutely valid.  The purpose of assert
>statements is to debug the code, by checking for conditions that are
>supposed to be impossible.

Precisely.  As I've stated elsewhere, this is an internal helper
function, to be called only a few times under very well-specified
conditions.  The assert statements checks that these conditions
are as intended.  I.e. they are checks against the module writer's
programming errors.


From no.email at please.post  Sat Jul  4 17:14:45 2009
From: no.email at please.post (kj)
Date: Sat, 4 Jul 2009 21:14:45 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<mailman.2621.1246733010.8015.python-list@python.org>
Message-ID: <h2ogo5$n9p$3@reader1.panix.com>

In <mailman.2621.1246733010.8015.python-list at python.org> MRAB <python at mrabarnett.plus.com> writes:

>Paul Rubin wrote:
>> kj <no.email at please.post> writes:
>>> This implies that code that uses *any* assert statement (other than
>>> perhaps the trivial and meaningless ones like "assert True") is
>>> liable to break, because whatever it is that these assert statements
>>> are checking "on some occasions, ... would go unchecked, potentially
>>> breaking your code."
>> 
>> Yes, that implication is absolutely valid.  The purpose of assert
>> statements is to debug the code, by checking for conditions that are
>> supposed to be impossible.  Unless the program is broken (i.e.  the
>> impossible happened), no assert statement should ever trigger.
>> 
>Technically these are known as "invariants". An assertion will always be
>True if the program is bug-free, no matter what the user might throw at
>it; it's not the same as validation.

What *user* are you talking about???  I've stated a bazillion times
that this function is meant to be called only from within this
module.



From hanooter at gmail.com  Sat Jul  4 18:06:29 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 15:06:29 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com> 
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
Message-ID: <d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>

On Jul 4, 12:51?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> mclovin wrote:
> > OK then. I will try some of the strategies here but I guess things
> > arent looking too good. I need to run this over a dataset that someone
> > pickled. I need to run this 480,000 times so you can see my
> > frustration. So it doesn't need to be "real time" but it would be nice
> > it was done sorting this month.
>
> > Is there a "bet guess" strategy where it is not 100% accurate but much
> > faster?
>
> Well, I timed a run of a version of mine, and the scan is approx 5X
> longer than the copy-and-sort. ?Time arr_of_arr.flatten().sort() to
> see how quickly the copy and sort happens.So you could try a variant
> exploiting the following property:
> ? ? ?If you know the minimum length of a run that will be in the top 25,
> then the value for each of the most-frequent run entries must show up at
> positions n * stride and (n + 1) * stride (for some n). ?That should
> drastically reduce the scan cost, as long as stride is reasonably large.
>
> For my uniformly distributed 0..1024 values in 5M x 5M array,
> About 2.5 sec to flatten and sort.
> About 15 sec to run one of my heapish thingies.
> the least frequency encountered: 24716
> so, with stride at
>
> sum(flattened[:-stride:stride] == flattened[stride::stride]) == 1000
> So there are only 1000 points to investigate.
> With any distribution other than uniform, that should go _way_ down.
> So just pull out those points, use bisect to get their frequencies, and
> feed those results into the heap accumulation.
>
> --Scott David Daniels

I dont quite understand what you are saying but I know this: the times
the most common element appears varies greatly. Sometimes it appears
over 1000 times, and some times it appears less than 50. It all
depends on the density of the arrays I am analyzing.

like I said I need to do this 480,000 times so to get this done
realistically I need to analyse about 5 a second. It appears that the
average matrix size contains about 15 million elements.

I threaded my program using your code and I did about 1,000 in an hour
so it is still much too slow.

When I selected 1 million random elements to count, 8 out of the top
10 of those were in the top 25 of the precise way and 18 of the 25
were in the top 25 of the precise way. so I suppose that could be an
option.


From sajmikins at gmail.com  Sat Jul  4 18:22:47 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sat, 4 Jul 2009 15:22:47 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com>
Message-ID: <acee1a4b-275a-4343-8204-9812f3d90471@q11g2000yqi.googlegroups.com>

On Jul 4, 12:30?pm, kj <no.em... at please.post> wrote:
> In <mailman.2611.1246721197.8015.python-l... at python.org> "Pablo Torres N." <tn.pa... at gmail.com> writes:
>
>
>
> >On Sat, Jul 4, 2009 at 10:05, kj<no.em... at please.post> wrote:
> >>>http://docs.python.org/reference/simple_stmts.html#grammar-token-asse...
> >tmt
> >>>"The current code generator emits no code for an assert statement when op=
> >timization is requested at compile time."
>
> >> Sorry, this doesn't say anything like "don't use assertions to test
> >> argument values". =C2=A0I'm aware of the fact that assertions are silence=
> >d
> >> under certain circumstances. =C2=A0But where does the principle 1. in
> >> your first reply come from? =C2=A0I've never seen it before, and would
> >> like to understand the reasoning behind it.
>
> >> kj
> >> --
> >>http://mail.python.org/mailman/listinfo/python-list
>
> >But...if no code is generated for assertions on some occasions, then the
> >parameters would go unchecked, potentially breaking your code in said
> >occasions.
>
> This implies that code that uses *any* assert statement (other than
> perhaps the trivial and meaningless ones like "assert True") is
> liable to break, because whatever it is that these assert statements
> are checking "on some occasions, ... would go unchecked, potentially
> breaking your code."
>
> I'm beginning to think that the original "precept" was simply "cargo
> cult," i.e. one of those rules that are parroted without being
> fully understood.
>
> As I wrote in my original post, the function I posted was an internal
> ("helper") function, not to be used outside of the file. ?This fact
> was further (ahem) underscored by the leading underscore in the
> function's name. ?Under these circumstances, the assert statements
> seem to me perfectly in keeping with the intended use for them.
>
> kj

Assertions are for you, the programmer, to check that your
understanding of the code is correct (or not, i.e. if the assertion
fails.)

It's unfortunately not uncommon to see code where the assert statement
is used as an integral part of the processing, or, in other words,
where running the code with '-O' will cause changes in the way the it
runs.

In the code you posted, the assert statements seem to be checking that
other code/algorithms aren't (will never) pass that function "out of
bounds" arguments.  Perfectly valid IMO.  Since it's an internal
helper function you can (should) know that client code will /always/
call it with valid values, the asserts simply make your intuition or
knowledge explicit in a way that will show up dramatically if you're
wrong about that (i.e. if there's some problem elsewhere in the code
feeding that function.)

Assertions should never fail, which is why you can (or should be able
to without breaking your code) remove them entirely and know that your
program will run identically.  That's why folks are quick to jump on
cases where assertions are used as control-flow constructs.  (In your
function, however, they aren't.)

In a sense, assertions /are/ meaningless, except to the programmer.

FWIW, you can use "if __debug__:" and put anything you like in the
statement suite and the whole if statement goes away when run with '-
O'. Sort of a "super-assert".

Regards,
~Simon


From http  Sat Jul  4 18:24:01 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 15:24:01 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
	<7x4otsux7f.fsf@ruckus.brouhaha.com>
	<h2oggj$n9p$1@reader1.panix.com>
Message-ID: <7xljn484u6.fsf@ruckus.brouhaha.com>

kj <no.email at please.post> writes:
> >bisection search usually just requires the function to be continuous
> >and to have its value cross the target somewhere between the endpoints,
> >not be monotonic.
> 
> Try the algorithm I posted with lo = -pi/4, hi = 2*pi, func = cos,
> target = -1, and see what you get...

Sorry, my comment was poorly phrase.  Bisection search usually is
phrased in terms of solving f(x)=0 where f is continuous and if the
initial endpoints are a and b, then f(a) and f(b) have opposite sign.

> You keep missing the point that this is an *internal* *helper*
> *convenience* function, ...  Any internal use of this function that
> applies it to a non-strictly-monotonic function is, by assumption,
> an error.

In that case there are better algorithms you can use.  But didn't this
thread start out asking what version of the code was best suited for
presentation to students?  In that case, the function's preconditions
should be stated explicitly and not be narrower than necessary.


From python at mrabarnett.plus.com  Sat Jul  4 18:29:41 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 04 Jul 2009 23:29:41 +0100
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
Message-ID: <4A4FD7D5.6050201@mrabarnett.plus.com>

mclovin wrote:
[snip]
> like I said I need to do this 480,000 times so to get this done
> realistically I need to analyse about 5 a second. It appears that the
> average matrix size contains about 15 million elements.
> 
> I threaded my program using your code and I did about 1,000 in an hour
> so it is still much too slow.
> 
> When I selected 1 million random elements to count, 8 out of the top
> 10 of those were in the top 25 of the precise way and 18 of the 25
> were in the top 25 of the precise way. so I suppose that could be an
> option.

The values are integers, aren't they? What is the range of values?


From hanooter at gmail.com  Sat Jul  4 18:33:38 2009
From: hanooter at gmail.com (mclovin)
Date: Sat, 4 Jul 2009 15:33:38 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com> 
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<mailman.2623.1246746585.8015.python-list@python.org>
Message-ID: <e1536b4d-c9ca-4376-8b98-f2b7994d2d18@q11g2000yqi.googlegroups.com>

On Jul 4, 3:29?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> mclovin wrote:
>
> [snip]
>
> > like I said I need to do this 480,000 times so to get this done
> > realistically I need to analyse about 5 a second. It appears that the
> > average matrix size contains about 15 million elements.
>
> > I threaded my program using your code and I did about 1,000 in an hour
> > so it is still much too slow.
>
> > When I selected 1 million random elements to count, 8 out of the top
> > 10 of those were in the top 25 of the precise way and 18 of the 25
> > were in the top 25 of the precise way. so I suppose that could be an
> > option.
>
> The values are integers, aren't they? What is the range of values?

There are appox 550k unique values with a range of 0-2million with
gaps.


From pavlovevidence at gmail.com  Sat Jul  4 18:47:57 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 4 Jul 2009 15:47:57 -0700 (PDT)
Subject: Searching equivalent to C++ RAII or deterministic destructors
References: <k63uh6-861.ln1@satorlaser.homedns.org>
	<6b17de68-9a8e-4896-b0fe-99dd12471314@j32g2000yqh.googlegroups.com>
	<3pduh6-g52.ln1@satorlaser.homedns.org>
	<6c15c237-c3e6-4eb7-aae3-0548e9ab279f@d7g2000prl.googlegroups.com>
	<mailman.2556.1246624444.8015.python-list@python.org>
Message-ID: <94eaeb9d-fe90-45fb-99ee-8846eb8cb19e@r33g2000yqn.googlegroups.com>

On Jul 3, 5:34?am, Jack Diederich <jackd... at gmail.com> wrote:
> On Thu, Jul 2, 2009 at 2:36 PM, Carl Banks<pavlovevide... at gmail.com> wrote:
> > Warning: objects with a __del__ attribute prevent reference cycle
> > detection, which can potentially lead to memory (and resource) leaks.
> > So you must be careful to avoid creating reference loops with that
> > object.
>
> WARNING-er: As Carl points out, adding a __del__ method actually makes
> it /less/ likely that your object will be cleaned up.

No I wasn't pointing that out, and I don't really agree with it.  (You
can't really say it is "more likely" or "less likely" without
considering the skill and patience of the programmer, and there are
many programmers who are up to the task.)

__del__ can succeed with care, and if you are willing to give up a
certain amount of flexibility and portability

I don't recommend going that way.  For one thing RAII isn't quite so
wonderful in Python's dynamic environment as it is in C++'s static
universe, and people seem to expect more from it than they get.
Second, relying on implementation-dependent behavior is not a good
thing and can set you up for problems later, something few people
expect to happen to them but it does more often than they think.
(Search comp.lang.python for a thread started by Warren DeLano for an
example of someone who got bit hard by such a change he should have
seen coming.)  But still I leave that for them to risk for themselves.


[snip]
>?If you care enough about a resource to write a __del__ method
> you care enough to clean it up explicitly. ?'with' blocks are very
> nice for that.

The OP already said with blocks won't suffice since the resources are
long-lived objects that aren't limited to a single scope.


Carl Banks


From Scott.Daniels at Acm.Org  Sat Jul  4 18:50:23 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sat, 04 Jul 2009 15:50:23 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
Message-ID: <4A4FDCAF.8010209@Acm.Org>

mclovin wrote:
> On Jul 4, 12:51 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
>> mclovin wrote:
>>> OK then. I will try some of the strategies here but I guess things
>>> arent looking too good. I need to run this over a dataset that someone
>>> pickled. I need to run this 480,000 times so you can see my
>>> frustration. So it doesn't need to be "real time" but it would be nice
>>> it was done sorting this month.
>>> Is there a "bet guess" strategy where it is not 100% accurate but much
>>> faster?
>>
>> Well, I timed a run of a version of mine, and the scan is approx 5X
>> longer than the copy-and-sort.  Time arr_of_arr.flatten().sort() to
>> see how quickly the copy and sort happens.So you could try a variant
>> exploiting the following property:
>>      If you know the minimum length of a run that will be in the top 25,
>> then the value for each of the most-frequent run entries must show up at
>> positions n * stride and (n + 1) * stride (for some n).  That should
>> drastically reduce the scan cost, as long as stride is reasonably large....
>>
>> sum(flattened[:-stride:stride] == flattened[stride::stride]) == 1000
>> So there are only 1000 points to investigate.
>> With any distribution other than uniform, that should go _way_ down.
>> So just pull out those points, use bisect to get their frequencies, and
>> feed those results into the heap accumulation.
>>
>> --Scott David Daniels
> 
> I dont quite understand what you are saying but I know this: the times
> the most common element appears varies greatly. Sometimes it appears
> over 1000 times, and some times it appears less than 50. It all
> depends on the density of the arrays I am analyzing.

Here's a heuristic replacement for my previous frequency code:
I've tried to mark where you could fudge numbers if the run time
is at all close.

def frequency(arr_of_arr, N, stride=100)
     '''produce (freq, value) pairs for data in arr_of_arr.

     Tries to produce > N pairs.  stride is a guess at half
     the length of the shortest run in the top N runs.
     '''
     # if the next two lines are too slow, this whole approach is toast
     data = arr_of_arr.flatten()  # big allocation
     data.sort() # a couple of seconds for 25 million ints

     # stride is a length forcing examination of a run.
     sampled = data[::stride]
     # Note this is a view into data, and is still sorted.
     # We know that any run of length 2 * stride - 1 in data _must_ have
     # consecutive entries in sampled.  Compare them "in parallel"
     matches = sampled[:-1] == sampled[1:]
     # matches is True or False for stride-separated values from sampled
     candidates = sum(matches) # count identified matches

     # while candidates is huge, keep trying with a larger stride
     while candidates > N *10: # 10 -- heuristic
         stride *= 2 # # heuristic increase
         sampled = data[::stride]
         matches = sampled[:-1] == sampled[1:]
         candidates = sum(matches)

     # if we got too few, move stride down:
     while candidates < N * 3: # heuristic slop for long runs
         stride //= 2 # heuristic decrease
         sampled = data[::stride]
         matches = sampled[:-1] == sampled[1:]
         candidates = sum(matches)

     # Here we have a "nice" list of candidates that is likely
     # to include every run we actually want. sampled[matches] is
     # the sorted list of candidate values.  It may have duplicates
     former = None
     past = 0
     # In the loop here we only use sampled to the pick values we
     # then go find in data.  We avoid checking for same value twice
     for value in sampled[matches]:
         if value == former:
             continue # A long run: multiple matches in sampled
         former = value # Make sure we only try this one once
         # find the beginning of the run
         start = bisect.bisect_left(data, value, past)
         # find the end of the run (we know it is at least stride long)
         past = bisect.bisect_right(data, value, start + stride)
         yield past - start, value # produce frequency, value data

--Scott David Daniels
Scott.Daniels at Acm.Org


From python at mrabarnett.plus.com  Sat Jul  4 19:05:50 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 05 Jul 2009 00:05:50 +0100
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <e1536b4d-c9ca-4376-8b98-f2b7994d2d18@q11g2000yqi.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>	<mailman.2623.1246746585.8015.python-list@python.org>
	<e1536b4d-c9ca-4376-8b98-f2b7994d2d18@q11g2000yqi.googlegroups.com>
Message-ID: <4A4FE04E.1050202@mrabarnett.plus.com>

mclovin wrote:
> On Jul 4, 3:29 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> mclovin wrote:
>>
>> [snip]
>>
>>> like I said I need to do this 480,000 times so to get this done
>>> realistically I need to analyse about 5 a second. It appears that the
>>> average matrix size contains about 15 million elements.
>>> I threaded my program using your code and I did about 1,000 in an hour
>>> so it is still much too slow.
>>> When I selected 1 million random elements to count, 8 out of the top
>>> 10 of those were in the top 25 of the precise way and 18 of the 25
>>> were in the top 25 of the precise way. so I suppose that could be an
>>> option.
>> The values are integers, aren't they? What is the range of values?
> 
> There are appox 550k unique values with a range of 0-2million with
> gaps.

I've done a little experimentation with lists (no numpy involved) and
found that I got a x2 speed increase if I did the counting using a list,
something like this:

counts = [0] * 2000000
for x in values:
     counts[x] += 1
counts = dict(e for e in enumerate(values) if e[1] != 0)


From hkmshb at gmail.com  Sat Jul  4 19:18:50 2009
From: hkmshb at gmail.com (Klone)
Date: Sat, 4 Jul 2009 16:18:50 -0700 (PDT)
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
	<b0b2ff61-9023-474c-b114-863107781971@y7g2000yqa.googlegroups.com> 
	<4d99b710-45f1-42dc-b80c-1894af26db42@p29g2000yqh.googlegroups.com>
Message-ID: <46ce50ea-0272-4285-ab06-65c4e53a1e99@k8g2000yqn.googlegroups.com>

Thank you all. I think I get the gist and am about trying your
suggestions.


From nagle at animats.com  Sat Jul  4 19:35:08 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 04 Jul 2009 16:35:08 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xvdm8thpo.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
Message-ID: <4a4fe6cb$0$1591$742ec2ed@news.sonic.net>

Paul Rubin wrote:
> John Nagle <nagle at animats.com> writes:
>> Python doesn't have a "switch" or "case" statement, and when
>> you need a state machine with many states, that makes for painful,
>> slow code.  ...
>> There's a comment in the code that it would be useful
>> to run a few billion lines of HTML through an instrumented version
>> of the parser to decide in which order the IF statements should be
>> executed.  You shouldn't have to do that.
> 
> In that particular program it would probably be better to change those
> if/elif/elif/else constructs to dictionary lookups.  I see the program
> already does that for some large tables.

    A dictionary lookup (actually, several of them) for every
input character is rather expensive. Tokenizers usually index into
a table of character classes, then use the character class index in
a switch statement.

    This is an issue that comes up whenever you have to parse some formal
structure, from XML/HTML to Pickle to JPEG images to program source.

    If Python could figure out what's a constant and what isn't during
compilation, this sort of thing could be much more efficient.  In fact,
you don't even need a switch statement at the source level, if the
language is such that the compiler can figure out when "elif" clauses
are mutually exclusive.

    The temptation is to write tokenizers in C, but that's an admission
of language design failure.

    (A general problem with Python is "hidden dynamism".  That is,
changes to variables that can't be found by examining the source.
This is a killer for optimizations. One could take the position that any
module variable with exactly one visible assignment to it is, in fact,
only assigned in one place, and if the right hand side is a constant,
the variable is a constant.  This would break some programs doing funny
stuff with "eval", or using some of the backdoor ways to modify variables,
but that's very rare in practice.  In return, you get the ability to
hard-compile more of Python into fast code.  I'm thinking Shed Skin here,
not yet another attempt at a JIT system.)

    On the other hand, trying to do this in Perl, where you can't even index
strings, is far worse.
	
				John Nagle


From http  Sat Jul  4 19:48:19 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 16:48:19 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <7xfxdcqabg.fsf@ruckus.brouhaha.com>

John Nagle <nagle at animats.com> writes:
>     A dictionary lookup (actually, several of them) for every
> input character is rather expensive. Tokenizers usually index into
> a table of character classes, then use the character class index in
> a switch statement.

Maybe you could use a regexp (and then have -two- problems...) to
find the token boundaries, then a dict to identify the actual token.
Tables of character classes seem a bit less attractive in the Unicode
era than in the old days.


From davea at ieee.org  Sat Jul  4 19:53:48 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 04 Jul 2009 19:53:48 -0400
Subject: Zipped Python?
In-Reply-To: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
References: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
Message-ID: <4A4FEB8C.4040302@ieee.org>

Jeremy Cowles wrote:
> Hi all,
>
> I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e. no
> install). My intentions are to use it for a distributed computing project
> (PyMW) where there is no guarantee that Python is installed on the worker
> machines and an interactive install is out of the question.
>
> I've been looking around, but I haven't been able to turn anything useful up
> so far. Any help would be appreciated.
>
> --
> Jeremy
>
>
>   
How about portable python:
      http://www.portablepython.com/

or Movable Python:
       http://www.voidspace.org.uk/python/movpy/


No experience with either, but they bear looking at.



From matt at tplus1.com  Sat Jul  4 20:03:38 2009
From: matt at tplus1.com (Matthew Wilson)
Date: Sun, 05 Jul 2009 00:03:38 GMT
Subject: Does cProfile include IO wait time?
Message-ID: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>

I have a command-line script that loads about 100 yaml files.  It takes
2 or 3 seconds.  I profiled my code and I'm using pstats to find what is
the bottleneck.

Here's the top 10 functions, sorted by internal time:

    In [5]: _3.sort_stats('time').print_stats(10)
    Sat Jul  4 13:25:40 2009    pitz_prof

             756872 function calls (739759 primitive calls) in 8.621 CPU seconds

       Ordered by: internal time
       List reduced from 1700 to 10 due to restriction <10>

       ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        15153    0.446    0.000    0.503    0.000 build/bdist.linux-i686/egg/yaml/reader.py:134(forward)
        30530    0.424    0.000    0.842    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:142(need_more_tokens)
        98037    0.423    0.000    0.423    0.000 build/bdist.linux-i686/egg/yaml/reader.py:122(peek)
         1955    0.415    0.000    1.265    0.001 build/bdist.linux-i686/egg/yaml/scanner.py:1275(scan_plain)
        69935    0.381    0.000    0.381    0.000 {isinstance}
        18901    0.329    0.000    3.908    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:113(check_token)
         5414    0.277    0.000    0.794    0.000 /home/matt/projects/pitz/pitz/__init__.py:34(f)
        30935    0.258    0.000    0.364    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:276(stale_possible_simple_keys)
        18945    0.192    0.000    0.314    0.000 /usr/local/lib/python2.6/uuid.py:180(__cmp__)
         2368    0.172    0.000    1.345    0.001 build/bdist.linux-i686/egg/yaml/parser.py:268(parse_node)

I expected to see a bunch of my IO file-reading code in there, but I don't.  So
this makes me think that the profiler uses CPU time, not
clock-on-the-wall time.

I'm not an expert on python profiling, and the docs seem sparse.  Can I
rule out IO as the bottleneck here?  How do I see the IO consequences?

TIA

Matt


From jeremy.cowles at gmail.com  Sat Jul  4 20:03:44 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Sat, 4 Jul 2009 17:03:44 -0700
Subject: Zipped Python?
In-Reply-To: <4A4FEB8C.4040302@ieee.org>
References: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
	<4A4FEB8C.4040302@ieee.org>
Message-ID: <373cf0740907041703g5250fc9cg346c2c6f2b6d992c@mail.gmail.com>

>
> I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e. no
>> install). My intentions are to use it for a distributed computing project
>> (PyMW) where there is no guarantee that Python is installed on the worker
>> machines and an interactive install is out of the question.
>>
>> I've been looking around, but I haven't been able to turn anything useful
>> up
>> so far. Any help would be appreciated.
>>
>>
>>  How about portable python:
>     http://www.portablepython.com/
>
> or Movable Python:
>      http://www.voidspace.org.uk/python/movpy/
>

Sorry, forgot - I need something that will work for Windows, Linux and Mac.
It could be 3 different distros (zips), but I need something for all three.

Both portable python and movable Python are Windows only.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090704/9a682c62/attachment-0001.html>

From ldo at geek-central.gen.new_zealand  Sat Jul  4 20:12:22 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 05 Jul 2009 12:12:22 +1200
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
Message-ID: <h2or56$bko$1@lust.ihug.co.nz>

In message <1beffd94-cfe6-4cf6-
bd48-2ccac8637796 at j32g2000yqh.googlegroups.com>, ryles wrote:

>>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which
>>>> # iter() will do. Sorry guys!
> 
> Please don't let this happen to you too ;)

Strange. others have got told off for using "== None" instead of "is None" 
<http://groups.google.co.nz/group/comp.lang.python/msg/a1f3170fa202af57>, 
and yet it turns out Python itself does exactly the same thing.



From emile at fenx.com  Sat Jul  4 21:00:29 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sat, 04 Jul 2009 18:00:29 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <h2otvh$tpv$1@ger.gmane.org>

On 7/4/2009 12:33 AM mclovin said...
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
> 
> so I set up a dictionary to handle the counting so when I am
> iterating  I 

   ** up the count on the corrosponding dictionary element **

Right at this point, instead of or in addition to counting, why not save 
the large array index in a list?  Then when you've identified the 25 
most common elements you'll already have a list of pointer to the 
instances to work from.

Emile




From sgm at objexx.com  Sat Jul  4 21:15:43 2009
From: sgm at objexx.com (SK)
Date: Sat, 4 Jul 2009 18:15:43 -0700 (PDT)
Subject: multiprocessing and freezing on Windows
References: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>
Message-ID: <a205db1d-a801-4774-bfa1-124a723ea71b@p36g2000prn.googlegroups.com>

To add a bit more information, I found that I needed to patch
get_command_line in multiprocessing/forking.py replacing:

        if getattr(sys, 'frozen', False):
            return [sys.executable, '--multiprocessing-fork']
        else:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']

with:

        if WINEXE:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']
        elif getattr(sys, 'frozen', False):
            return [sys.executable, '--multiprocessing-fork']
        else:
            prog = 'from multiprocessing.forking import main; main()'
            return [_python_exe, '-c', prog, '--multiprocessing-fork']

and then using py2exe I can get a working "frozen" package if I
include pythonw.exe and a subset of Python's Lib directory in my
package and call multiprocessing.set_executable to point to that
pythonw.exe.

Does the above patch address a real bug?

Is packaging with multiprocessing supposed to be this hard? If so,
some documentation is needed.


From nobody at nowhere.com  Sat Jul  4 21:25:38 2009
From: nobody at nowhere.com (Nobody)
Date: Sun, 05 Jul 2009 02:25:38 +0100
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <pan.2009.07.05.01.25.37.813000@nowhere.com>

On Sat, 04 Jul 2009 16:35:08 -0700, John Nagle wrote:

>     The temptation is to write tokenizers in C, but that's an admission
> of language design failure.

The only part that really needs to be written in C is the DFA loop. The
code to construct the state table from regexps could be written
entirely in Python, but I don't see any advantage to doing so.



From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:27:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:27:30 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<mailman.2621.1246733010.8015.python-list@python.org>
	<h2ogo5$n9p$3@reader1.panix.com>
Message-ID: <025ff310$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 21:14:45 +0000, kj wrote:

>>Technically these are known as "invariants". An assertion will always be
>>True if the program is bug-free, no matter what the user might throw at
>>it; it's not the same as validation.
> 
> What *user* are you talking about???  I've stated a bazillion times that
> this function is meant to be called only from within this module.

In that case, you would be the user, and like any user, you might 
accidentally call the function with invalid data.

I believe this discussion started because you are presenting this as code 
for novices. In that case, it is absolutely important that you start off 
by teaching them the Right Way to do things. As a general rule, the Right 
Way is to do an explicit test and raise rather than use assert.

In production code, "internal use only" code is a grey area where assert 
is sometimes justified (although I'll point out that in practice, code 
written for internal use only has a habit of being called by others). But 
you're not writing production code, you're writing *teaching code*, where 
even more important than code correctness is user education.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:31:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:31:23 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
Message-ID: <025ff3f9$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 15:06:29 -0700, mclovin wrote:

> like I said I need to do this 480,000 times so to get this done
> realistically I need to analyse about 5 a second. It appears that the
> average matrix size contains about 15 million elements.

Have you considered recording the element counts as you construct the 
arrays? This will marginally increase the time it takes to build the 
array, but turn finding the most frequent elements into a very quick 
operation.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:35:31 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:35:31 GMT
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<h2or56$bko$1@lust.ihug.co.nz>
Message-ID: <025ff4f1$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 12:12:22 +1200, Lawrence D'Oliveiro wrote:

> In message <1beffd94-cfe6-4cf6-
> bd48-2ccac8637796 at j32g2000yqh.googlegroups.com>, ryles wrote:
> 
>>>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which
>>>>> # iter() will do. Sorry guys!
>> 
>> Please don't let this happen to you too ;)
> 
> Strange. others have got told off for using "== None" instead of "is
> None"
> <http://groups.google.co.nz/group/comp.lang.python/msg/
a1f3170fa202af57>,
> and yet it turns out Python itself does exactly the same thing.

That's not "strange", that's a bug. Did you report it to the tracker?



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:36:13 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:36:13 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
Message-ID: <025ff51b$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 11:10:48 -0700, Paul Rubin wrote:

> Anyway, Python's overloading of bool(...) is yet another misfeature and
> although it's convenient, the "explicit is better than implicit"
> principle indicates to avoid that sort of trick.

"Overloading of bool()"?

I don't understand what that means -- you mean you dislike the ability to 
overload __bool__ (__nonzero__ in older Pythons)? That seems strange. 
Python allows you to overload __int__ and __str__ and __float__, why is 
__bool__ a misfeature? If that's what you mean, then I'm perplexed.

Or do you mean that all Python objects are interpretable in a truth 
context? If that's what you mean, then I'm not perplexed, I'm sure you're 
utterly wrong. Certain people -- a tiny minority -- keep trying to argue 
that the ability to say "if obj" for arbitrary objects is somehow a bad 
thing, and their arguments seem to always boil down to:

"If you write code that assumes that only bools have a truth value, then 
surprising things will happen because all objects have a truth value."

Well duh.

If you think you have a better reason for calling the truth value of 
arbitrary objects a "misfeature", I'd like to hear it.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul  4 21:39:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 01:39:33 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
Message-ID: <025ff5e2$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 07:19:48 -0700, Scott David Daniels wrote:

> Actually the next step is to maintain a min-heap as you run down the
> sorted array.  Something like:

Not bad.

I did some tests on it, using the following sample data:

arr = np.array([xrange(i, i+7000) for i in xrange(143)] + 
      [[750]*7000] + [xrange(3*i, 3*i+7000) for i in xrange(142)])


and compared your code against the following simple function:


def count(arr, N):
    D = {}
    for v in arr:
        for x in v:
            D[x] = D.get(x, 0) + 1
    freq = []
    for el, f in D.iteritems():
        freq.append((f, el))
    return sorted(freq, reverse=True)[:N]


As a rough figure, your min-heap code is approximately twice as fast as 
mine.

To the OP: I think you should start profiling your code and find out 
exactly *where* it is slow and concentrate on that. I think that trying a 
heuristic to estimate the most frequent elements by taking a random 
sample is likely to be a mistake -- whatever you're trying to accomplish 
with the frequency counts, the use of such a heuristic will mean that 
you're only approximately accomplishing it.



-- 
Steven


From ben+python at benfinney.id.au  Sat Jul  4 22:09:12 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 05 Jul 2009 12:09:12 +1000
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <87tz1rrid3.fsf@benfinney.id.au>

John Nagle <nagle at animats.com> writes:

>    A dictionary lookup (actually, several of them) for every input
> character is rather expensive. Tokenizers usually index into a table
> of character classes, then use the character class index in a switch
> statement.
> 
>    This is an issue that comes up whenever you have to parse some
> formal structure, from XML/HTML to Pickle to JPEG images to program
> source.
> [?] 
>    The temptation is to write tokenizers in C, but that's an admission
> of language design failure.

This sounds like a job for <URL:http://pyparsing.wikispaces.com/>
Pyparsing.

-- 
 \          ?Better not take a dog on the space shuttle, because if he |
  `\   sticks his head out when you're coming home his face might burn |
_o__)                                                up.? ?Jack Handey |
Ben Finney


From benjamin.kaplan at case.edu  Sat Jul  4 22:28:23 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Sat, 4 Jul 2009 22:28:23 -0400
Subject: Zipped Python?
In-Reply-To: <373cf0740907041703g5250fc9cg346c2c6f2b6d992c@mail.gmail.com>
References: <373cf0740907041044q673b0e1u4341bdee84bef1d5@mail.gmail.com>
	<4A4FEB8C.4040302@ieee.org>
	<373cf0740907041703g5250fc9cg346c2c6f2b6d992c@mail.gmail.com>
Message-ID: <ec96e1390907041928j136c3296nfcdc478279bbabef@mail.gmail.com>

On Sat, Jul 4, 2009 at 8:03 PM, Jeremy Cowles<jeremy.cowles at gmail.com> wrote:
>>> I'm looking for a full 2.5 or 2.6 version of Python that is zipped (i.e.
>>> no
>>> install). My intentions are to use it for a distributed computing project
>>> (PyMW) where there is no guarantee that Python is installed on the worker
>>> machines and an interactive install is out of the question.
>>>
>>> I've been looking around, but I haven't been able to turn anything useful
>>> up
>>> so far. Any help would be appreciated.
>>>
>>>
>> How about portable python:
>> ? ? http://www.portablepython.com/
>>
>> or Movable Python:
>> ? ? ?http://www.voidspace.org.uk/python/movpy/
>
> Sorry, forgot - I need something that will work for Windows, Linux and Mac.
> It could be 3 different distros (zips), but I need something for all three.
> Both portable python and movable Python are Windows only.

OS X and most, if not all, Linux distributions come with Python
preinstalled (they use them for system features) so no one bothered to
make something like Portable Python for them.

> --
> http://mail.python.org/mailman/listinfo/python-list
>
>


From nagle at animats.com  Sat Jul  4 23:15:11 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 04 Jul 2009 20:15:11 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xfxdcqabg.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
Message-ID: <4a501a5e$0$1640$742ec2ed@news.sonic.net>

Paul Rubin wrote:
> John Nagle <nagle at animats.com> writes:
>>     A dictionary lookup (actually, several of them) for every
>> input character is rather expensive. Tokenizers usually index into
>> a table of character classes, then use the character class index in
>> a switch statement.
> 
> Maybe you could use a regexp (and then have -two- problems...) to
> find the token boundaries, then a dict to identify the actual token.
> Tables of character classes seem a bit less attractive in the Unicode
> era than in the old days.

    I want to see a regular expression that expresses the HTML 5 token
parsing rules, including all the explicitly specified error handling.

    Here's some actual code, from "tokenizer.py".  This is called once
for each character in an HTML document, when in "data" state (outside
a tag).  It's straightforward code, but look at all those
dictionary lookups.

     def dataState(self):
         data = self.stream.char()

         # Keep a charbuffer to handle the escapeFlag
         if self.contentModelFlag in\
           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
             if len(self.lastFourChars) == 4:
                 self.lastFourChars.pop(0)
             self.lastFourChars.append(data)

         # The rest of the logic
         if data == "&" and self.contentModelFlag in\
           (contentModelFlags["PCDATA"], contentModelFlags["RCDATA"]) and not\
           self.escapeFlag:
             self.state = self.states["entityData"]
         elif data == "-" and self.contentModelFlag in\
           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and not\
           self.escapeFlag and "".join(self.lastFourChars) == "<!--":
             self.escapeFlag = True
             self.tokenQueue.append({"type": "Characters", "data":data})
         elif (data == "<" and (self.contentModelFlag == contentModelFlags["PCDATA"]
                                or (self.contentModelFlag in
                                    (contentModelFlags["CDATA"],
                                     contentModelFlags["RCDATA"]) and
                                    self.escapeFlag == False))):
             self.state = self.states["tagOpen"]
         elif data == ">" and self.contentModelFlag in\
           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and\
           self.escapeFlag and "".join(self.lastFourChars)[1:] == "-->":
             self.escapeFlag = False
             self.tokenQueue.append({"type": "Characters", "data":data})
         elif data == EOF:
             # Tokenization ends.
             return False
         elif data in spaceCharacters:
             # Directly after emitting a token you switch back to the "data
             # state". At that point spaceCharacters are important so they are
             # emitted separately.
             self.tokenQueue.append({"type": "SpaceCharacters", "data":
               data + self.stream.charsUntil(spaceCharacters, True)})
             # No need to update lastFourChars here, since the first space will
             # have already broken any <!-- or --> sequences
         else:
             chars = self.stream.charsUntil(("&", "<", ">", "-"))
             self.tokenQueue.append({"type": "Characters", "data":
               data + chars})
             self.lastFourChars += chars[-4:]
             self.lastFourChars = self.lastFourChars[-4:]
         return True



					John Nagle


From kyosohma at gmail.com  Sat Jul  4 23:17:07 2009
From: kyosohma at gmail.com (Mike Driscoll)
Date: Sat, 4 Jul 2009 20:17:07 -0700 (PDT)
Subject: Pyowa is this Monday!
Message-ID: <7224400c-cadc-403f-b090-74cb49373dee@h11g2000yqb.googlegroups.com>

Hi,

The next Pyowa meeting is on Monday, July 6th from 7-9 p.m. We will be
at the Marshall County Sheriff's Office (directions on website).
Currently, the plan is to have a talk about Python at Fisher/Emerson
that will segue into a general discussion of what we do with our
favorite programming language. Be prepared to share!

We may have another presentation in our Standard Library series as
well or just something random. Let me know if you think you'll be
there. Pop & water will be provided. We hope to see you there!

--------------------------
Mike Driscoll

http://www.pyowa.org
http://pyowa.blip.tv/
http://twitter.com/pyowa
http://upcoming.yahoo.com/event/2853430/
Mailing list: http://pyowalist.pythonlibrary.org/listinfo.cgi/pyowa-pythonlibrary.org


From aahz at pythoncraft.com  Sat Jul  4 23:37:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 4 Jul 2009 20:37:16 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <h2p75c$65r$1@panix3.panix.com>

In article <4a501a5e$0$1640$742ec2ed at news.sonic.net>,
John Nagle  <nagle at animats.com> wrote:
>
>    Here's some actual code, from "tokenizer.py".  This is called once
>for each character in an HTML document, when in "data" state (outside
>a tag).  It's straightforward code, but look at all those
>dictionary lookups.
>
>     def dataState(self):
>         data = self.stream.char()
>
>         # Keep a charbuffer to handle the escapeFlag
>         if self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
>             if len(self.lastFourChars) == 4:
>                 self.lastFourChars.pop(0)
>             self.lastFourChars.append(data)
>
>         # The rest of the logic
>         if data == "&" and self.contentModelFlag in\
>           (contentModelFlags["PCDATA"], contentModelFlags["RCDATA"]) and not\
>           self.escapeFlag:
>             self.state = self.states["entityData"]
>         elif data == "-" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and not\
>           self.escapeFlag and "".join(self.lastFourChars) == "<!--":
>             self.escapeFlag = True
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif (data == "<" and (self.contentModelFlag == contentModelFlags["PCDATA"]
>                                or (self.contentModelFlag in
>                                    (contentModelFlags["CDATA"],
>                                     contentModelFlags["RCDATA"]) and
>                                    self.escapeFlag == False))):
>             self.state = self.states["tagOpen"]
>         elif data == ">" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and\
>           self.escapeFlag and "".join(self.lastFourChars)[1:] == "-->":
>             self.escapeFlag = False
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif data == EOF:
>             # Tokenization ends.
>             return False
>         elif data in spaceCharacters:
>             # Directly after emitting a token you switch back to the "data
>             # state". At that point spaceCharacters are important so they are
>             # emitted separately.
>             self.tokenQueue.append({"type": "SpaceCharacters", "data":
>               data + self.stream.charsUntil(spaceCharacters, True)})
>             # No need to update lastFourChars here, since the first space will
>             # have already broken any <!-- or --> sequences
>         else:
>             chars = self.stream.charsUntil(("&", "<", ">", "-"))
>             self.tokenQueue.append({"type": "Characters", "data":
>               data + chars})
>             self.lastFourChars += chars[-4:]
>             self.lastFourChars = self.lastFourChars[-4:]
>         return True

Every single "self." is a dictionary lookup.  Were you referring to
those?  If not, I don't see your point.  If yes, well, that's kind of the
whole point of using Python.  You do pay a performance penalty.  You can
optimize out some lookups, but you need to switch to C for some kinds of
computationally intensive algorithms.  In this case, you can probably get
a large boost out of Pysco or Cython or Pyrex.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From tn.pablo at gmail.com  Sun Jul  5 00:26:39 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sat, 4 Jul 2009 23:26:39 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2on0d$i57$1@ger.gmane.org>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com> <h2on0d$i57$1@ger.gmane.org>
Message-ID: <fdd00b510907042126n4d0ca869wbe892777bab00690@mail.gmail.com>

On Sat, Jul 4, 2009 at 18:01, Dennis Lee Bieber<wlfraed at ix.netcom.com> wrote:
> ? ? ? ?Do you really want to inflict novices with the subtleties of when
> "assert" is a proper structure to use?

I'll second that.  This very thread is proof that assertions are polemic, so
maybe you (kj) should just save your student's sanity and stick to good old
conditionals :-)

As for your initial question, I think, thirty four emails after, that yes, your
function is a bit too clever and you should sacrifice some generality in order
to make it more readable.


-- 
Pablo Torres N.


From pavlovevidence at gmail.com  Sun Jul  5 01:51:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 4 Jul 2009 22:51:52 -0700 (PDT)
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com> 
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <4c2c7b44-23cd-43b4-8086-1b7cf6a14954@n11g2000yqb.googlegroups.com>

On Jul 4, 4:35?pm, John Nagle <na... at animats.com> wrote:
> ? ? The temptation is to write tokenizers in C, but that's an admission
> of language design failure.

No it isn't.  It's only a failure of Python to be the language that
does everything *you* want.

Carl Banks


From http  Sun Jul  5 02:17:21 2009
From: http (Paul Rubin)
Date: 04 Jul 2009 23:17:21 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xfxdbk61a.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Certain people -- a tiny minority -- keep trying to argue 
> that the ability to say "if obj" for arbitrary objects is somehow a bad 
> thing, and their arguments seem to always boil down to:
> "If you write code that assumes that only bools have a truth value, then 
> surprising things will happen because all objects have a truth value."

I'd put it under the general rubric of "explicit is better than
implicit".  The language shouldn't do silly automatic typecasts all
over the place.  Yes, it saves a few keystrokes to say "if x:" instead
of "if len(x)==0:" or even "if bool(x):", but if I program in a style
where I like to think I know the type of something when I use it, I'd
like the interpreter to let me know when I'm wrong instead of
proceeding silently.


From nick at craig-wood.com  Sun Jul  5 03:30:04 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Sun, 05 Jul 2009 02:30:04 -0500
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <slrnh50ljc.1jp.nick@irishsea.home.craig-wood.com>

John Nagle <nagle at animats.com> wrote:
>      As an example of code that really needs to run fast, but is
>  speed-limited by Python's limitations, see "tokenizer.py" in
> 
>  	http://code.google.com/p/html5lib/
> 
>  This is a parser for HTML 5, a piece of code that will be needed
>  in many places and will process large amounts of data. It's written
>  entirely in Python.  Take a look at how much work has to be performed
>  per character.
> 
>  This is a good test for Python implementation bottlenecks.  Run
>  that tokenizer on HTML, and see where the time goes.
> 
>  ("It should be written in C" is not an acceptable answer.)

You could compile it with Cython though.  lxml took this route...

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From pm567426 at gmail.com  Sun Jul  5 03:38:30 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 00:38:30 -0700 (PDT)
Subject: How Python Implements "long integer"?
Message-ID: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>

Hello,
I'm reading about implementation of long ints in Python. I downloaded
the source code of CPython and will read the longobject.c, but from
where I should start reading this file? I mean which function is the
first?
Anyone can help?
Thanks

Pedram


From mail at microcorp.co.za  Sun Jul  5 04:12:54 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 5 Jul 2009 10:12:54 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <006201c9fd48$666d94e0$0d00a8c0@Hendrik>

"John Nagle" <nagle at ...ats.com> wrote:

> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code.  There's a comment in the code that it would be useful
> to run a few billion lines of HTML through an instrumented version
> of the parser to decide in which order the IF statements should be
> executed.  You shouldn't have to do that.

You do not have to implement a state machine in a case statement,
or in a series of if... elifs.

Python is not C.

Use a dispatch dict, and have each state return the next state.
Then you can use strings representing state names, and
everybody will be able to understand the code.

toy example, not tested, nor completed:

protocol = {"start":initialiser,"hunt":hunter,"classify":classifier,....other
states}

def state_machine():
    next_step = protocol["start"]()
    while True:
        next_step = protocol[next_step]()

Simple, and almost as fast as if you did the same thing
in assembler using pointers.

And each state will have a finite set of reasons to
either stay where its at, or move on.  Not a lot you
can do about that, but test for them one at a time.
But at least you will have split the problem up,
and you won't be doing irrelevant tests.

You can even do away with the dict, by having
each state return the actual next state routine:

next_state = protocol_initialiser()
while True:
    next_state = next_state()
    time.sleep(0.001)      # this prevents thrashing when monitoring real events

If you are using a gui, and you have access
to an after callback, then you can make a
ticking stutter thread to run some monitoring
machine in the background, using the same
"tell me what to do next" technique.

To take the timing thing further, you can do:

wait_time, next_state = protocol_initialiser()
while True:
    if wait_time:
        time.sleep(wait_time)
    wait_time, next_state = next_state()

This gives you control over busy-wait loops,
and lets you speed up when it is needed.

Python really is not C.

- Hendrik






From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 04:28:01 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 08:28:01 GMT
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <0260559c$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 20:15:11 -0700, John Nagle wrote:

> Paul Rubin wrote:
>> John Nagle <nagle at animats.com> writes:
>>>     A dictionary lookup (actually, several of them) for every
>>> input character is rather expensive. Tokenizers usually index into a
>>> table of character classes, then use the character class index in a
>>> switch statement.
>> 
>> Maybe you could use a regexp (and then have -two- problems...) to find
>> the token boundaries, then a dict to identify the actual token. Tables
>> of character classes seem a bit less attractive in the Unicode era than
>> in the old days.
> 
>     I want to see a regular expression that expresses the HTML 5 token
> parsing rules, including all the explicitly specified error handling.

Obviously the regex can't do the error handling. Nor should you expect a 
single regex to parse an entire HTML document. But you could (perhaps) 
use regexes to parse pieces of the document, as needed.

Have you investigated the pyparsing module? Unless you have some reason 
for avoiding it, for any complicated parsing job I'd turn to that before 
trying to roll your own.


>     Here's some actual code, from "tokenizer.py".  This is called once
> for each character in an HTML document, when in "data" state (outside a
> tag).  It's straightforward code, but look at all those dictionary
> lookups.

Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't 
see how a case statement would help you here: you're not dispatching on a 
value, but running through a series of tests until one passes. There are 
languages where you can write something like:

case:
    x > 0: process_positive(x)
    x < 0: process_negative(x)
    x == 0: process_zero(x)

but that's generally just syntactic sugar for the obvious if...elif... 
block. (Although clever compilers might recognise that it's the same x in 
each expression, and do something clever to optimize the code.)


Nor do I see why you were complaining about Python not having true 
constants. I don't see how that would help you... most of your explicit 
dict lookups are against string literals e.g. contentModelFlags["RCDATA"].

So while I feel your pain, I'm not sure I understand why you're blaming 
this on *Python*.


-- 
Steven


From stefan_ml at behnel.de  Sun Jul  5 04:41:58 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 10:41:58 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <4a506755$0$31333$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
> Python doesn't have a "switch" or "case" statement, and when
> you need a state machine with many states, that makes for painful,
> slow code.

Cython has a built-in optimisation that maps if-elif-else chains to C's
switch statement if they only test a single int/char variable, even when
you write things like "elif x in [1,5,9,12]". This works in Cython, because
we know that the comparison to a C int/char is side-effect free. It may not
always be side-effect free in Python, so this won't work in general. It
would be perfect for your case, though.

Stefan


From http  Sun Jul  5 04:58:13 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 01:58:13 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xws6nik0q.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't 
> see how a case statement would help you here: you're not dispatching on a 
> value, but running through a series of tests until one passes. 

A case statement switch(x):... into a bunch of constant case labels
would be able to use x as an index into a jump vector, and/or do an
unrolled logarithmic (bisection-like) search through the tests,
instead of a linear search.


From stefan_ml at behnel.de  Sun Jul  5 04:58:27 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 10:58:27 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a501a5e$0$1640$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
>    Here's some actual code, from "tokenizer.py".  This is called once
> for each character in an HTML document, when in "data" state (outside
> a tag).  It's straightforward code, but look at all those
> dictionary lookups.
> 
>     def dataState(self):
>         data = self.stream.char()
> 
>         # Keep a charbuffer to handle the escapeFlag
>         if self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):

Is the tuple

	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])

constant? If that is the case, I'd cut it out into a class member (or
module-local variable) first thing in the morning. And I'd definitely keep
the result of the "in" test in a local variable for reuse, seeing how many
times it's used in the rest of the code.

Writing inefficient code is not something to blame the language for.

Stefan


From stefan_ml at behnel.de  Sun Jul  5 05:04:33 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 11:04:33 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
Message-ID: <4a506ca1$0$31344$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
> Paul Rubin wrote:
>> John Nagle <nagle at animats.com> writes:
>>> Python doesn't have a "switch" or "case" statement, and when
>>> you need a state machine with many states, that makes for painful,
>>> slow code.  ...
>>> There's a comment in the code that it would be useful
>>> to run a few billion lines of HTML through an instrumented version
>>> of the parser to decide in which order the IF statements should be
>>> executed.  You shouldn't have to do that.
>>
>> In that particular program it would probably be better to change those
>> if/elif/elif/else constructs to dictionary lookups.  I see the program
>> already does that for some large tables.
> 
>    A dictionary lookup (actually, several of them) for every
> input character is rather expensive.

Did you implement this and prove your claim in benchmarks? Taking a look at
the current implementation, I'm pretty sure a dict-based implementation
would outrun it in your first try.

Stefan


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 05:04:58 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 09:04:58 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
Message-ID: <02605e46$0$20657$c3e8da3@news.astraweb.com>

On Sat, 04 Jul 2009 23:17:21 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> Certain people -- a tiny minority -- keep trying to argue that the
>> ability to say "if obj" for arbitrary objects is somehow a bad thing,
>> and their arguments seem to always boil down to: "If you write code
>> that assumes that only bools have a truth value, then surprising things
>> will happen because all objects have a truth value."
> 
> I'd put it under the general rubric of "explicit is better than
> implicit".  

"if x" is explicit. It's difficult to see how a branch could be anything 
other than explicit, but never mind.


> The language shouldn't do silly automatic typecasts all over
> the place.  

"if x" doesn't involve a typecast. Python doesn't have typecasts, except 
possibly for the special case of myobject.__class__ = Another_Class.

If you mean Python shouldn't do silly automatic type conversions all over 
the place, I absolutely agree with you! Fortunately, testing the truth 
value of an object isn't a silly automatic type conversion.


> Yes, it saves a few keystrokes to say "if x:" instead of "if
> len(x)==0:" or even "if bool(x):", 


It's not about saving keystrokes -- that's a furphy. It's about 
encapsulation. Objects are in a better position to recognise when they 
are "something" (true) or "nothing" (false) than you are.

Given an arbitrary object x, how do you know if it's something or 
nothing? In general, you can't tell -- but the object can, provided it's 
well written. (The conspicuous exception is iterators, but that's a 
special case.)

"if len(x) == 0" is wasteful. Perhaps I've passed you a list-like 
iterable instead of a list, and calculating the actual length is O(N). 
Why spend all that effort to find out the length of the object is 
59,872,819 only to throw that away? My object knows when it's empty, but 
instead you make foolish assumptions about the object and consequently 
write wastefully slow code.


> but if I program in a style where I
> like to think I know the type of something when I use it, I'd like the
> interpreter to let me know when I'm wrong instead of proceeding
> silently.

Oh come on now... that's a silly objection. If you want strongly-typed 
variables in Python, say so, don't pretend this is a failure of truth-
testing. If you write len(x)==0 Python doesn't complain if x is a dict 
instead of the list you were expecting. Why is it acceptable to duck-type 
len(x) but not truth-testing?


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 05:07:50 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 09:07:50 GMT
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<mailman.2631.1246781750.8015.python-list@python.org>
Message-ID: <02605ef2$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 10:12:54 +0200, Hendrik van Rooyen wrote:

> Python is not C.

John Nagle is an old hand at Python. He's perfectly aware of this, and 
I'm sure he's not trying to program C in Python.

I'm not entirely sure *what* he is doing, and hopefully he'll speak up 
and say, but whatever the problem is it's not going to be as simple as 
that.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 05:13:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 09:13:23 GMT
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
Message-ID: <0260603f$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 01:58:13 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't
>> see how a case statement would help you here: you're not dispatching on
>> a value, but running through a series of tests until one passes.
> 
> A case statement switch(x):... into a bunch of constant case labels
> would be able to use x as an index into a jump vector, and/or do an
> unrolled logarithmic (bisection-like) search through the tests, instead
> of a linear search.

Yes, I'm aware of that, but that's not what John's code is doing -- he's 
doing a series of if expr ... elif expr tests. I don't think a case 
statement can do much to optimize that.



-- 
Steven


From stef.mientki at gmail.com  Sun Jul  5 05:35:14 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 05 Jul 2009 11:35:14 +0200
Subject: Adding an object to the global namespace through " f_globals"
	is   that allowed ?
In-Reply-To: <h2hgbj$sp5$1@ger.gmane.org>
References: <4A4BC22D.70502@gmail.com> <h2hgbj$sp5$1@ger.gmane.org>
Message-ID: <4A5073D2.4010000@gmail.com>

Terry Reedy wrote:
> Stef Mientki wrote:
>> hello,
>>
>> I need to add an object's name to the global namespace.
>> The reason for this is to create an environment,
>> where you can add some kind of math environment,
>> where no need for Python knowledge is needed.
>>
>> The next statement works,
>> but I'm not sure if it will have any dramatical side effects,
>> other than overruling a possible object with the name A
>>
>> def some_function ( ...) :
>>      A = object ( ...)
>>      sys._getframe(1).f_globals [ Name ] = A
>
> global name
> name = A
>
> or is name is a string var
> globals()[name] = A
great, the last 2 lines works in most cases.
Now to get everything working correctly, I have to use both globals() 
and f_globals()
but everything seems to work perfect now.

thanks for all the hints.
cheers,
Stef



From http  Sun Jul  5 05:38:54 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 02:38:54 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xr5wvtqoh.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Yes, I'm aware of that, but that's not what John's code is doing -- he's 
> doing a series of if expr ... elif expr tests. I don't think a case 
> statement can do much to optimize that.

The series of tests is written that way because there is no case
statement available.  It is essentially switching on a bunch of
character constants and then doing some additional tests in each
branch.

It could be that using ord(c) as an index into a list of functions
might be faster than a dict lookup on c to get a function.  I think
John is hoping to avoid a function call and instead get an indexed
jump within the Python bytecode for the big function.


From stefan_ml at behnel.de  Sun Jul  5 05:41:18 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 11:41:18 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <4a50753e$0$31331$9b4e6d93@newsspool4.arcor-online.net>

Stefan Behnel wrote:
> John Nagle wrote:
>>    Here's some actual code, from "tokenizer.py".  This is called once
>> for each character in an HTML document, when in "data" state (outside
>> a tag).  It's straightforward code, but look at all those
>> dictionary lookups.
>>
>>     def dataState(self):
>>         data = self.stream.char()
>>
>>         # Keep a charbuffer to handle the escapeFlag
>>         if self.contentModelFlag in\
>>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
> 
> Is the tuple
> 
> 	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])
> 
> constant? If that is the case, I'd cut it out into a class member (or
> module-local variable) first thing in the morning.

Ah, and there's also this little trick to make it a (fast) local variable
in that method:

	def some_method(self, some_const=(1,2,3,4)):
	    ...

Stefan


From stefan_ml at behnel.de  Sun Jul  5 05:48:38 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 11:48:38 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xr5wvtqoh.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
Message-ID: <4a5076f8$0$31341$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Steven D'Aprano writes:
>> Yes, I'm aware of that, but that's not what John's code is doing -- he's 
>> doing a series of if expr ... elif expr tests. I don't think a case 
>> statement can do much to optimize that.
> 
> The series of tests is written that way because there is no case
> statement available.  It is essentially switching on a bunch of
> character constants and then doing some additional tests in each
> branch.

Although doing some of the tests first and then checking the input
conditionally might be faster here.

Another idea: You could exchange the methods whenever self.contentModelFlag
changes, i.e. you'd have a "dataState_CDATA", a "dataState_PCDATA" etc.


> It could be that using ord(c) as an index into a list of functions
> might be faster than a dict lookup on c to get a function.

Rather unlikely, given that calling "ord(c)" involves a dict lookup for
"ord". You might get away with the pre-initialised keywords trick, though.


> I think
> John is hoping to avoid a function call and instead get an indexed
> jump within the Python bytecode for the big function.

Hmm, yes, the actual code inside the conditionals is pretty short, so the
call overhead might hurt here.

Stefan


From http  Sun Jul  5 05:52:17 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 02:52:17 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7x7hyn5uem.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:
> >         # Keep a charbuffer to handle the escapeFlag
> >         if self.contentModelFlag in\
> >           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
> Is the tuple
> 	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])
> constant? If that is the case, I'd cut it out into a class member ...

I think the main issue for that function comes after that if statement.
There is a multi-way switch on a bunch of different possible character
values.  I do agree with you that the first "if" can also be optimized.


From ldo at geek-central.gen.new_zealand  Sun Jul  5 05:52:22 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 05 Jul 2009 21:52:22 +1200
Subject: Multi thread reading a file
References: <1cbd6f830906301852t4febbb02q99528f2d6ec94a82@mail.gmail.com>
	<mailman.2426.1246424006.8015.python-list@python.org>
	<dJidneWgY4R4HtbXnZ2dnUVZ_hadnZ2d@pdx.net>
	<mailman.2478.1246529340.8015.python-list@python.org>
	<1beffd94-cfe6-4cf6-bd48-2ccac8637796@j32g2000yqh.googlegroups.com>
	<h2or56$bko$1@lust.ihug.co.nz>
	<025ff4f1$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <h2pt4n$vs1$2@lust.ihug.co.nz>

In message <025ff4f1$0$20657$c3e8da3 at news.astraweb.com>, Steven D'Aprano wrote:

> On Sun, 05 Jul 2009 12:12:22 +1200, Lawrence D'Oliveiro wrote:
> 
>> In message <1beffd94-cfe6-4cf6-bd48-2ccac8637796 at j32g2000yqh.googlegroups.com>, ryles wrote:
>> 
>>>>>> # Oh... yeah. I really *did* want 'is None' and not '== None' which
>>>>>> # iter() will do. Sorry guys!
>>> 
>>> Please don't let this happen to you too ;)
>> 
>> Strange. others have got told off for using "== None" instead of "is
>> None" <http://groups.google.co.nz/group/comp.lang.python/msg/a1f3170fa202af57>,
>> and yet it turns out Python itself does exactly the same thing.
> 
> That's not "strange", that's a bug.

It's not a bug, as Gabriel Genellina has pointed out.



From http  Sun Jul  5 05:54:23 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 02:54:23 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<4a5076f8$0$31341$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7x3a9b5ub4.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:
> > The series of tests is written that way because there is no case
> > statement available.  It is essentially switching on a bunch of
> > character constants and then doing some additional tests in each
> > branch.
> Although doing some of the tests first and then checking the input
> conditionally might be faster here.

That is essentially what happens.  There are a bunch of tests of the
form
   if data=='<' and [some other stuff]: ...

Because of short-circuit evaluation of "and", the additional tests
only happen once the character has been matched.


From ldo at geek-central.gen.new_zealand  Sun Jul  5 05:54:37 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 05 Jul 2009 21:54:37 +1200
Subject: Is code duplication allowed in this instance?
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
Message-ID: <h2pt8u$vs1$3@lust.ihug.co.nz>

In message <ddb65af7-8820-4a83-bc92-
c1d1c62d69fb at y17g2000yqn.googlegroups.com>, Klone wrote:

> So in this scenario is it OK to duplicate the algorithm to be tested
> within the test codes or refactor the method such that it can be used
> within test codes to verify itself(??).

I think you should be put on the management fast-track.



From dickinsm at gmail.com  Sun Jul  5 05:57:02 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Sun, 5 Jul 2009 02:57:02 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
Message-ID: <ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>

On Jul 5, 8:38?am, Pedram <pm567... at gmail.com> wrote:
> Hello,
> I'm reading about implementation of long ints in Python. I downloaded
> the source code of CPython and will read the longobject.c, but from
> where I should start reading this file? I mean which function is the
> first?

I don't really understand the question:  what do you mean by 'first'?
It might help if you tell us what your aims are.

In any case, you probably also want to look at the Include/
longintrepr.h and Include/longobject.h files.

Mark


From stefan_ml at behnel.de  Sun Jul  5 06:04:43 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 12:04:43 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7x3a9b5ub4.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<4a5076f8$0$31341$9b4e6d93@newsspool4.arcor-online.net>
	<7x3a9b5ub4.fsf@ruckus.brouhaha.com>
Message-ID: <4a507abb$0$31327$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Stefan Behnel writes:
>>> The series of tests is written that way because there is no case
>>> statement available.  It is essentially switching on a bunch of
>>> character constants and then doing some additional tests in each
>>> branch.
>> Although doing some of the tests first and then checking the input
>> conditionally might be faster here.
> 
> That is essentially what happens.  There are a bunch of tests of the
> form
>    if data=='<' and [some other stuff]: ...

That's what I meant. Some of the "other stuff" is redundant enough to do it
once at the beginning of the function (or even before entering the
function, by writing specialised methods), i.e. I'd (partially) reverse the
order of the "and" operands.

Stefan


From stefan_ml at behnel.de  Sun Jul  5 06:06:49 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 12:06:49 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7x7hyn5uem.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
	<7x7hyn5uem.fsf@ruckus.brouhaha.com>
Message-ID: <4a507b39$0$31327$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Stefan Behnel writes:
>>>         # Keep a charbuffer to handle the escapeFlag
>>>         if self.contentModelFlag in\
>>>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
>> Is the tuple
>> 	(contentModelFlags["CDATA"], contentModelFlags["RCDATA"])
>> constant? If that is the case, I'd cut it out into a class member ...
> 
> I think the main issue for that function comes after that if statement.
> There is a multi-way switch on a bunch of different possible character
> values.  I do agree with you that the first "if" can also be optimized.

You may notice that the creation of this exact tuple appears in almost all
if the conditionals of this method. So it is part of the bottleneck.

Stefan


From http  Sun Jul  5 06:08:16 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 03:08:16 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7xy6r34f3j.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> > Yes, it saves a few keystrokes to say "if x:" instead of "if
> > len(x)==0:" or even "if bool(x):", 
> 
> It's not about saving keystrokes -- that's a furphy. It's about 
> encapsulation. Objects are in a better position to recognise when they 
> are "something" (true) or "nothing" (false) than you are.

I don't know what a furphy is, but I don't accept that "somethingness"
vs. "nothingness" is the same distinction as truth vs falsehood.  True
and False are values in a specific datatype (namely bool), not
abstract qualities of arbitrary data structures.  The idea that the
"if" statement selects between "somethingness" and "nothingness"
rather than between True and False is a bogus re-imagining of the
traditional function of an "if" statement and has been an endless
source of bugs in Python code.  Look how much confusion it causes here
in the newsgroup all the time.

> "if len(x) == 0" is wasteful. Perhaps I've passed you a list-like 
> iterable instead of a list, and calculating the actual length is O(N). 

That doesn't happen in any of Python's built-in container types.  I
could see some value to having a generic "is_empty" predicate on
containers though, to deal with this situation.  Your iterable could
support that predicate.  In fact maybe all iterables should support
that predicate.  They don't (and can't) all support "len".

> If you write len(x)==0 Python doesn't complain if x is a dict
> instead of the list you were expecting. Why is it acceptable to
> duck-type len(x) but not truth-testing?

I haven't seen the amount of bugs coming from generic "len" as from
something-vs-nothing confusion.


From http  Sun Jul  5 07:09:26 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 04:09:26 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
	<7x7hyn5uem.fsf@ruckus.brouhaha.com>
	<4a507b39$0$31327$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7xljn3bd3t.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:
> You may notice that the creation of this exact tuple appears in almost all
> if the conditionals of this method. So it is part of the bottleneck.

I don't think so.  The tuple is only created when the character has
already matched, and for the vast majority of the chars in the input
stream (ordinary text chars rather than html delimiters) none of them
match.


From stefan_ml at behnel.de  Sun Jul  5 07:23:23 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 13:23:23 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <7xljn3bd3t.fsf@ruckus.brouhaha.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<4a506b33$0$31344$9b4e6d93@newsspool4.arcor-online.net>
	<7x7hyn5uem.fsf@ruckus.brouhaha.com>
	<4a507b39$0$31327$9b4e6d93@newsspool4.arcor-online.net>
	<7xljn3bd3t.fsf@ruckus.brouhaha.com>
Message-ID: <4a508d2c$0$31332$9b4e6d93@newsspool4.arcor-online.net>

Paul Rubin wrote:
> Stefan Behnel writes:
>> You may notice that the creation of this exact tuple appears in almost all
>> if the conditionals of this method. So it is part of the bottleneck.
> 
> I don't think so.  The tuple is only created when the character has
> already matched, and for the vast majority of the chars in the input
> stream (ordinary text chars rather than html delimiters) none of them
> match.

Well, it's the second thing that happens when entering the method, it
happens several times later on when specific characters are matched, and it
also happens at the end when none of the special characters did match. So
it /is/ part of the bottleneck because the dict lookups, the tuple
creation, the "in" test and the tuple deallocation happen *twice* for
almost all characters in the stream.

Stefan


From 13139781969 at mymetropcs.com  Sun Jul  5 07:36:00 2009
From: 13139781969 at mymetropcs.com (13139781969 at mymetropcs.com)
Date: Sun, 5 Jul 2009 06:36:00 -0500
Subject: No subject
Message-ID: <1295065.145352441246808164305.JavaMail.mms@mms12.mms.metropcs.net>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090705/d84f24ad/attachment-0001.html>
-------------- next part --------------
(Homer & Marge having sex with Bart Simpson)

From lie.1296 at gmail.com  Sun Jul  5 07:37:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 05 Jul 2009 11:37:49 GMT
Subject: question of style
In-Reply-To: <7xy6r34f3j.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
Message-ID: <hg04m.2790$ze1.2441@news-server.bigpond.net.au>

Paul Rubin wrote:
> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> "if len(x) == 0" is wasteful. Perhaps I've passed you a list-like 
>> iterable instead of a list, and calculating the actual length is O(N). 
> 
> That doesn't happen in any of Python's built-in container types.  I
> could see some value to having a generic "is_empty" predicate on
> containers though, to deal with this situation.  Your iterable could
> support that predicate.  In fact maybe all iterables should support
> that predicate.  They don't (and can't) all support "len".

That doesn't happen because all python's built-in container keep track
of its own length and are able to quickly determine its own length. But
outside builtins, certain iterables cannot determine its own length
quickly, e.g. iterators, but may have alternative ways to determine
whether itself is empty (through a "private" attributes). If you peek
through this private attribute, you're breaking encapsulation. Although
python is a language of consenting adults and doesn't really have a real
private, codes that breaks encapsulation is prone to bugs.

>>> Yes, it saves a few keystrokes to say "if x:" instead of "if
>>> len(x)==0:" or even "if bool(x):",
>> It's not about saving keystrokes -- that's a furphy. It's about
>> encapsulation. Objects are in a better position to recognise when
>> they are "something" (true) or "nothing" (false) than you are.
>
> I don't know what a furphy is, but I don't accept that "somethingness"
> vs. "nothingness" is the same distinction as truth vs falsehood.  True
> and False are values in a specific datatype (namely bool), not
> abstract qualities of arbitrary data structures.  The idea that the
> "if" statement selects between "somethingness" and "nothingness"
> rather than between True and False is a bogus re-imagining of the
> traditional function of an "if" statement and has been an endless
> source of bugs in Python code.  Look how much confusion it causes here
> in the newsgroup all the time.

Neither python's `if` nor `if` in formal logic is about testing True vs.
False. `if` in python and formal logic receives a statement. The
statement must be evaluatable to True or False, but does not have to be
True or False themselves. It just happens that True evaluates to True
and False evaluates to False. For example, the statement:

P := `e = 2.7182818284590451`
Q := `e = m*c**2`
----------------------------------
P -> Q

P -> Q evaluates to:
`e = 2.7182818284590451` -> `e = m*c**2`

Note that `e = 2.7182818284590451` is a statement, not a boolean value.
The truth value of `e = 2.7182818284590451` is determined by "calling"
(note the double quotes) `e = 2.7182818284590451`.statement_is_true(),
which when written in python syntax becomes: (e ==
2.7182818284590451).__bool__()

>> If you write len(x)==0 Python doesn't complain if x is a dict
>> instead of the list you were expecting. Why is it acceptable to
>> duck-type len(x) but not truth-testing?
> 
> I haven't seen the amount of bugs coming from generic "len" as from
> something-vs-nothing confusion.


From ptmcg at austin.rr.com  Sun Jul  5 07:41:27 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Sun, 5 Jul 2009 04:41:27 -0700 (PDT)
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<mailman.2631.1246781750.8015.python-list@python.org>
Message-ID: <7061fac4-954d-49e2-a03b-3ed8653a99f3@o6g2000yqj.googlegroups.com>

On Jul 5, 3:12 am, "Hendrik van Rooyen" <m... at microcorp.co.za> wrote:
>
> Use a dispatch dict, and have each state return the next state.
> Then you can use strings representing state names, and
> everybody will be able to understand the code.
>
> toy example, not tested, nor completed:
>
> protocol = {"start":initialiser,"hunt":hunter,"classify":classifier,....other
> states}
>
> def state_machine():
>     next_step = protocol["start"]()
>     while True:
>         next_step = protocol[next_step]()
>

I've just spent about an hour looking over this code, with a few
comments to inject to the thread here:

- To all those suggesting the OP convert to a dispatch table, be
assured that this code is well aware of this idiom.  It is used
HEAVILY at a macro level, picking through the various HTML states
(starting a tag, reading attributes, reading body, etc.).  There still
are a number of cascading if-elif's within some of these states, and
some of them *may* be candidates for further optimization.

- There is an underlying HTMLInputStream that seems to be doing some
unnecessary position bookkeeping (positionLine and positionCol).
Commenting this out increases my test speed by about 13%.  In my
ignorance, I may be removing some important behavior, but this does
not seem to be critical as I tested against a few megs of HTML
source.  Before blaming the tokenizer for everything, there may be
more performance to be wrung from the input stream processor.  For
that matter, I would guess that about 90% of all HTML files that this
code would process would easily fit in memory - in that case, the
stream processing (and all of the attendant "if I'm not at the end of
the current chunk" code) could be skipped/removed entirely.

- The HTMLInputStream's charsUntil code is an already-identified
bottleneck, and some re enhancements have been applied here to help
out.

- Run-time construction of tuple literals where the tuple members are
constants can be lifted out.  emitCurrentToken rebuilds this tuple
every time it is called (which is a lot!):

    if (token["type"] in (tokenTypes["StartTag"], tokenTypes
["EndTag"], tokenTypes["EmptyTag"])):

Move this tuple literal into a class constant (or if you can tolerate
it, a default method argument to gain LOAD_FAST benefits - sometimes
optimization isn't pretty).

- These kinds of optimizations are pretty small, and only make sense
if they are called frequently.  Tallying which states are called in my
test gives the following list in decreasing frequency.  Such a list
would help guide your further tuning efforts:

tagNameState	194848
dataState	182179
attributeNameState	116507
attributeValueDoubleQuotedState	114931
tagOpenState	105556
beforeAttributeNameState	58612
beforeAttributeValueState	58216
afterAttributeValueState	58083
closeTagOpenState	50547
entityDataState	1673
attributeValueSingleQuotedState	1098
commentEndDashState	372
markupDeclarationOpenState	370
commentEndState	364
commentStartState	362
commentState	362
selfClosingStartTagState	359
doctypePublicIdentifierDoubleQuotedState	291
doctypeSystemIdentifierDoubleQuotedState	247
attributeValueUnQuotedState	191
doctypeNameState	32
beforeDoctypePublicIdentifierState	16
afterDoctypePublicIdentifierState	14
afterDoctypeNameState	9
doctypeState	8
beforeDoctypeNameState	8
afterDoctypeSystemIdentifierState	6
afterAttributeNameState	5
commentStartDashState	2
bogusCommentState	2

For instance, I wouldn't bother doing much tuning of the
bogusCommentState.  Anything called fewer than 50,000 times in this
test doesn't look like it would be worth the trouble.


-- Paul

(Thanks to those who suggested pyparsing as an alternative, but I
think this code is already beyond pyparsing in a few respects.  For
one thing, this code works with an input stream, in order to process
large HTML files; pyparsing *only* works with an in-memory string.
This code can also take advantage of some performance short cuts,
knowing that it is parsing HTML; pyparsing's generic classes can't do
that.)


From stefan_ml at behnel.de  Sun Jul  5 07:52:07 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Sun, 05 Jul 2009 13:52:07 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a501a5e$0$1640$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
Message-ID: <4a5093e7$0$31338$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
>    Here's some actual code, from "tokenizer.py".  This is called once
> for each character in an HTML document, when in "data" state (outside
> a tag).  It's straightforward code, but look at all those
> dictionary lookups.
> 
>     def dataState(self):
>         data = self.stream.char()
> 
>         # Keep a charbuffer to handle the escapeFlag
>         if self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]):
>             if len(self.lastFourChars) == 4:
>                 self.lastFourChars.pop(0)
>             self.lastFourChars.append(data)
> 
>         # The rest of the logic
>         if data == "&" and self.contentModelFlag in\
>           (contentModelFlags["PCDATA"], contentModelFlags["RCDATA"]) and
> not\
>           self.escapeFlag:
>             self.state = self.states["entityData"]
>         elif data == "-" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and
> not\
>           self.escapeFlag and "".join(self.lastFourChars) == "<!--":
>             self.escapeFlag = True
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif (data == "<" and (self.contentModelFlag ==
> contentModelFlags["PCDATA"]
>                                or (self.contentModelFlag in
>                                    (contentModelFlags["CDATA"],
>                                     contentModelFlags["RCDATA"]) and
>                                    self.escapeFlag == False))):
>             self.state = self.states["tagOpen"]
>         elif data == ">" and self.contentModelFlag in\
>           (contentModelFlags["CDATA"], contentModelFlags["RCDATA"]) and\
>           self.escapeFlag and "".join(self.lastFourChars)[1:] == "-->":
>             self.escapeFlag = False
>             self.tokenQueue.append({"type": "Characters", "data":data})
>         elif data == EOF:
>             # Tokenization ends.
>             return False
>         elif data in spaceCharacters:
>             # Directly after emitting a token you switch back to the "data
>             # state". At that point spaceCharacters are important so
> they are
>             # emitted separately.
>             self.tokenQueue.append({"type": "SpaceCharacters", "data":
>               data + self.stream.charsUntil(spaceCharacters, True)})
>             # No need to update lastFourChars here, since the first
> space will
>             # have already broken any <!-- or --> sequences
>         else:
>             chars = self.stream.charsUntil(("&", "<", ">", "-"))
>             self.tokenQueue.append({"type": "Characters", "data":
>               data + chars})
>             self.lastFourChars += chars[-4:]
>             self.lastFourChars = self.lastFourChars[-4:]
>         return True

Giving this some more thought, I'd also try is to split the huge
if-elif-else block like this:

        if data in string_with_all_special_characters:
            if data == '&' ...:
                ...
        else:
            ...

So there are three things to improve:

- eliminate common subexpressions which you know are constant
- split the large conditional sequence as shown above
- use separate dataState() methods when inside and outside of CDATA/RCDATA
  blocks and (maybe) escaped blocks

Stefan


From pm567426 at gmail.com  Sun Jul  5 08:09:49 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 05:09:49 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
Message-ID: <68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com>

On Jul 5, 1:57?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 5, 8:38?am, Pedram <pm567... at gmail.com> wrote:
>
> > Hello,
> > I'm reading about implementation of long ints in Python. I downloaded
> > the source code of CPython and will read the longobject.c, but from
> > where I should start reading this file? I mean which function is the
> > first?
>
> I don't really understand the question: ?what do you mean by 'first'?
> It might help if you tell us what your aims are.
>
> In any case, you probably also want to look at the Include/
> longintrepr.h and Include/longobject.h files.
>
> Mark

Thanks for reply,
Sorry I can't explain too clear! I'm not English ;)
But I want to understand the implementation of long int object in
Python. How Python allocates memory and how it implements operations
for this object?
Although, I'm reading the source code (longobject.c and as you said,
longintrepr.h and longobject.h) but if you can help me, I really
appreciate that.

Pedram


From drobinow at gmail.com  Sun Jul  5 08:21:33 2009
From: drobinow at gmail.com (David Robinow)
Date: Sun, 5 Jul 2009 08:21:33 -0400
Subject: Is code duplication allowed in this instance?
In-Reply-To: <h2pt8u$vs1$3@lust.ihug.co.nz>
References: <ddb65af7-8820-4a83-bc92-c1d1c62d69fb@y17g2000yqn.googlegroups.com>
	<h2pt8u$vs1$3@lust.ihug.co.nz>
Message-ID: <4eb0089f0907050521n8d0f6eo271ec18c10040290@mail.gmail.com>

On Sun, Jul 5, 2009 at 5:54 AM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> In message <ddb65af7-8820-4a83-bc92-
> c1d1c62d69fb at y17g2000yqn.googlegroups.com>, Klone wrote:
>
>> So in this scenario is it OK to duplicate the algorithm to be tested
>> within the test codes or refactor the method such that it can be used
>> within test codes to verify itself(??).
>
> I think you should be put on the management fast-track.
 Heavens, no. He's too valuable as a managee.


From mjohnson at cfi.co.ug  Sun Jul  5 08:27:12 2009
From: mjohnson at cfi.co.ug (Johnson Mpeirwe)
Date: Sun, 5 Jul 2009 16:27:12 +0400
Subject: PSP Caching
In-Reply-To: <3e1c0979-fb6b-4d6e-80e5-a4af8d5fd96a@a36g2000yqc.googlegroups.com>
References: <mailman.2548.1246612730.8015.python-list@python.org>
	<3e1c0979-fb6b-4d6e-80e5-a4af8d5fd96a@a36g2000yqc.googlegroups.com>
Message-ID: <20090705122217.M97570@cfi.co.ug>

Thanks Simon,

I got around this behavior by adding "MaxRequestsPerChild  1" (default value
of this is 0) to my httpd.conf to limit the number of requests a child server
process will handle before it dies but I think it is important to keep it 0 in
production environment.

Regards,
Johnson

On Fri, 3 Jul 2009 10:44:52 -0700 (PDT), Simon Forman wrote
> On Jul 3, 5:18?am, Johnson Mpeirwe <mjohn... at cfi.co.ug> wrote:
> > Hello All,
> >
> > How do I stop caching of Python Server Pages (or whatever causes changes
> > in a page not to be noticed in a web browser)? I am new to developing
> > web applications in Python and after looking at implementations of PSP
> > like Spyce (which I believed introduces new unnecessary non-PSP syntax),
> > I decided to write my own PSP applications from scratch. When I modify a
> > file, I keep getting the old results until I intentionally introduce an
> > error (e.g parse error) and correct it after to have the changes
> > noticed. There's no proxy (I am working on a windows machine unplugged
> > from the network). I have Googled and no documents seem to talk about
> > this. Is there any particular mod_python directive I must set in my
> > Apache configuration to fix this?
> >
> > Any help will be highly appreciated.
> >
> > Johnson
> 
> I don't know much about caching with apache, but the answer mght be 
> on this page: http://httpd.apache.org/docs/2.2/caching.html
> 
> Meanwhile, couldn't you just send apache a restart signal when you
> modify your code?
> 
> HTH,
> ~Simon
> -- 
> http://mail.python.org/mailman/listinfo/python-list



From dickinsm at gmail.com  Sun Jul  5 09:04:11 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Sun, 5 Jul 2009 06:04:11 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com> 
	<68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com>
Message-ID: <249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>

On Jul 5, 1:09?pm, Pedram <pm567... at gmail.com> wrote:
> Thanks for reply,
> Sorry I can't explain too clear! I'm not English ;)

That's shocking.  Everyone should be English. :-)

> But I want to understand the implementation of long int object in
> Python. How Python allocates memory and how it implements operations
> for this object?

I'd pick one operation (e.g., addition), and trace through the
relevant functions in longobject.c.  Look at the long_as_number
table to see where to get started.

In the case of addition, that table shows that the nb_add slot is
given by long_add.  long_add does any necessary type conversions
(CONVERT_BINOP) and then calls either x_sub or x_add to do the real
work.
x_add calls _PyLong_New to allocate space for a new PyLongObject, then
does the usual digit-by-digit-with-carry addition.  Finally, it
normalizes
the result (removes any unnecessary zeros) and returns.

As far as memory allocation goes: almost all operations call
_PyLong_New at some point.  (Except in py3k, where it's a bit more
complicated because small integers are cached.)

If you have more specific questions I'll have a go at answering them.

Mark


From http  Sun Jul  5 09:12:25 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 06:12:25 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<025eaa4f$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7x1vovxohy.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> > I wouldn't say Python's None is terrible,...
> No, wait, I tell I lie... re.search() sometimes bites me, because 
> sometimes it returns None and sometimes it returns a matchobject and I 
> don't use re often enough to have good habits with it yet.

re is a common source of this type of bug but there are others.
> There are three natural approaches to (say) re.search() for dealing with 
> failure:
> 
> (1) return a sentinel value like None;
> (2) return a matchobject which tests False;
> (3) raise an exception.

4. Have re.search return a bool and possible matchobject separately:

   put_match_here = []
   if re.search(pat, s, target=put_match_here):
      do_something_with(put_match_here[0])

or alternatively (cleaner), have a new type of object which supports
search operations while self-updating with the match object:

   mt = re.match_target()
   ...
   if mt.search(pat, s):
      do_something_with(mt.match)
   if mt.search(pat2, s):
      do_another_thing_with(mt.match)
   ...

This is sort of inspired by what Perl does.  I often do something like
this because it makes it cleaner to chain a series of matches.


From mail at microcorp.co.za  Sun Jul  5 09:45:45 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 5 Jul 2009 15:45:45 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net><mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <00f201c9fd76$e61565a0$0d00a8c0@Hendrik>

"Steven D'Aprano" <steve at REMOVE-THIS-cy..e.com.au> wrote:

>On Sun, 05 Jul 2009 10:12:54 +0200, Hendrik van Rooyen wrote:
>
>> Python is not C.
>
>John Nagle is an old hand at Python. He's perfectly aware of this, and 
>I'm sure he's not trying to program C in Python.
>
>I'm not entirely sure *what* he is doing, and hopefully he'll speak up 
>and say, but whatever the problem is it's not going to be as simple as 
>that.

I am well aware that John is not a newbie.
He was complaining about Python's lack of a case statement
in the context of a state machine.

The point I was trying to make is that, if any state machine
is examined, then, if you examine any one state, the reasons
for leaving it ("state transitions") is always a subset of the
choices that _can_ be made.

So that drawing a circle round each state in a state diagram, 
and making a routine to examine the arrows leaving that circle,
and returning the destination point of the chosen arrow,
is a way of splitting the job up, and results in making only 
the relevant decisions at the time of their relevance.

This is in contrast to the classic C way of making one big
case statement to implement a finite state machine, which
gets its efficiency (if any) out of compiler optimisations
such as replacing a skip chain with a jump table.

I understand that it leads to a lot of what looks like 
boilerplate code, but he was looking for speed...

- Hendrik





From mail at microcorp.co.za  Sun Jul  5 10:03:05 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 5 Jul 2009 16:03:05 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net><7xvdm8thpo.fsf@ruckus.brouhaha.com><4a4fe6cb$0$1591$742ec2ed@news.sonic.net><7xfxdcqabg.fsf@ruckus.brouhaha.com><4a501a5e$0$1640$742ec2ed@news.sonic.net><0260559c$0$20657$c3e8da3@news.astraweb.com><7xws6nik0q.fsf@ruckus.brouhaha.com><0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
Message-ID: <00f901c9fd79$51d12160$0d00a8c0@Hendrik>

"Paul Rubin" <http://phr.cx at NOSPAM.invalid> wrote:

> The series of tests is written that way because there is no case
> statement available.  It is essentially switching on a bunch of
> character constants and then doing some additional tests in each
> branch.
> 
> It could be that using ord(c) as an index into a list of functions
> might be faster than a dict lookup on c to get a function.  I think
> John is hoping to avoid a function call and instead get an indexed
> jump within the Python bytecode for the big function.

I agree about the ord(c). However, avoiding the function call
is, I think, right now, in the realms of wishful thinking.

I cannot see how you could avoid a python function call - even if he
bites the bullet and implements my laborious scheme, he would still 
have to fetch the next character to test against, inside the current state.

So if it is the function calls that is slowing him down, I cannot
imagine a solution using less than one per character, in which
case he is screwed no matter what he does.

But wait - maybe if he passes an iterator around - the equivalent of
for char in input_stream...
Still no good though, unless the next call to the iterator is faster
than an ordinary python call.

- Hendrik





From pm567426 at gmail.com  Sun Jul  5 10:15:11 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 07:15:11 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com> 
	<68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com> 
	<249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>
Message-ID: <e0c38d40-187b-4765-83f4-96dea8251f8c@d4g2000yqa.googlegroups.com>

On Jul 5, 5:04?pm, Mark Dickinson <dicki... at gmail.com> wrote:

> That's shocking. ?Everyone should be English. :-)

Yes, I'm trying :)

> I'd pick one operation (e.g., addition), and trace through the
> relevant functions in longobject.c. ?Look at the long_as_number
> table to see where to get started.
>
> In the case of addition, that table shows that the nb_add slot is
> given by long_add. ?long_add does any necessary type conversions
> (CONVERT_BINOP) and then calls either x_sub or x_add to do the real
> work.
> x_add calls _PyLong_New to allocate space for a new PyLongObject, then
> does the usual digit-by-digit-with-carry addition. ?Finally, it
> normalizes
> the result (removes any unnecessary zeros) and returns.
>
> As far as memory allocation goes: almost all operations call
> _PyLong_New at some point. ?(Except in py3k, where it's a bit more
> complicated because small integers are cached.)

Oh, I didn't see long_as_number before. I'm reading it. That was very
helpful, thanks.

> If you have more specific questions I'll have a go at answering them.
>
> Mark

Thank you a million.
I will write your name in my "Specially thanks to" section of my
article (In font size 72) ;)

Pedram


From l.mastrodomenico at gmail.com  Sun Jul  5 10:25:31 2009
From: l.mastrodomenico at gmail.com (Lino Mastrodomenico)
Date: Sun, 5 Jul 2009 16:25:31 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <00f901c9fd79$51d12160$0d00a8c0@Hendrik>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<7xvdm8thpo.fsf@ruckus.brouhaha.com>
	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>
	<7xfxdcqabg.fsf@ruckus.brouhaha.com>
	<4a501a5e$0$1640$742ec2ed@news.sonic.net>
	<0260559c$0$20657$c3e8da3@news.astraweb.com>
	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<00f901c9fd79$51d12160$0d00a8c0@Hendrik>
Message-ID: <cc93256f0907050725o24d7fda0i19bad5b6d69cc877@mail.gmail.com>

2009/7/5 Hendrik van Rooyen <mail at microcorp.co.za>:
> I cannot see how you could avoid a python function call - even if he
> bites the bullet and implements my laborious scheme, he would still
> have to fetch the next character to test against, inside the current state.
>
> So if it is the function calls that is slowing him down, I cannot
> imagine a solution using less than one per character, in which
> case he is screwed no matter what he does.

A simple solution may be to read the whole input HTML file in a
string. This potentially requires lots of memory but I suspect that
the use case by far most common for this parser is to build a DOM (or
DOM-like) tree of the whole document. This tree usually requires much
more memory that the HTML source itself.

So, if the code duplication is acceptable, I suggest keeping this
implementation for cases where the input is extremely big *AND* the
whole program will work on it in "streaming", not just the parser
itself.

Then write a simpler and faster parser for the more common case when
the data is not huge *OR* the user will keep the whole document in
memory anyway (e.g. on a tree).

Also: profile, profile a lot. HTML pages are very strange beasts and
the bottlenecks may be in innocent-looking places!

-- 
Lino Mastrodomenico


From tn.pablo at gmail.com  Sun Jul  5 10:30:47 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Sun, 5 Jul 2009 09:30:47 -0500
Subject: How Python Implements "long integer"?
In-Reply-To: <ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
Message-ID: <fdd00b510907050730r4390303eiaed973bd3408f03c@mail.gmail.com>

On Sun, Jul 5, 2009 at 04:57, Mark Dickinson<dickinsm at gmail.com> wrote:
> On Jul 5, 8:38?am, Pedram <pm567... at gmail.com> wrote:
>> Hello,
>> I'm reading about implementation of long ints in Python. I downloaded
>> the source code of CPython and will read the longobject.c, but from
>> where I should start reading this file? I mean which function is the
>> first?
>
> I don't really understand the question: ?what do you mean by 'first'?
> It might help if you tell us what your aims are.

I think he means the entry point, problem is that libraries have many.


-- 
Pablo Torres N.


From asm198 at gmail.com  Sun Jul  5 10:56:26 2009
From: asm198 at gmail.com (Icarus)
Date: Sun, 5 Jul 2009 07:56:26 -0700 (PDT)
Subject: Problems with using queue in Tkinter application
References: <0dae5496-622a-4fca-a2f5-6ba2ecac1284@r33g2000yqn.googlegroups.com>
	<h2n3d8$kvq$00$1@news.t-online.com>
	<c46b4e76-2c0d-49b5-bb97-c7e38934ac46@y7g2000yqa.googlegroups.com>
	<h2nvmi$9oh$03$1@news.t-online.com>
Message-ID: <39985616-d6b4-42f5-9db6-e7827f97c21d@24g2000yqm.googlegroups.com>

On Jul 4, 11:24?am, Peter Otten <__pete... at web.de> wrote:
> Icarus wrote:
> > On Jul 4, 3:21 am, Peter Otten <__pete... at web.de> wrote:
> >> Icarus wrote:
> >> > I'm working on a serial protocol analyzer in python. ?We have an
> >> > application written by someone else in MFC but we need something that
> >> > is cross platform. ?I intended to implement the GUI portion in Tkinter
> >> > but am having trouble.
>
> >> > The idea is that I will read messages from the serial port and output
> >> > them to a Tkinter Text object initially. ?Eventually it will have
> >> > other functionality but that's it for the short term. ?I've written
> >> > this little test app to experiment with putting things on the GUI via
> >> > a Queue which is polled by the Tkinter loop.
>
> >> > On some machines this code works fine and I get whatever I type in
> >> > displayed in the Text widget. ?On others I get errors like this as
> >> > soon as I start it running.
>
> >> > error in background error handler:
> >> > out of stack space (infinite loop?)
> >> > while executing
> >> > "::tcl::Bgerror {out of stack space (infinite loop?)} {-code 1 -level
> >> > 0 -errorcode NONE -errorinfo {out of stack space (infinite loop?)
> >> > while execu..."
>
> >> > I don't understand why on some machines it works exactly as expected
> >> > and on others it acts the same way Tkinter does when I call functions
> >> > directly from outside the Tkinter thread. ?Does anyone have any
> >> > suggestions? ?The full code as appended below. ?Thanks in advance.
>
> >> > [code]
>
> >> > import Queue
>
> >> > class functionQueue:
>
> >> > def __init__(self, root = None, timeout = 250):
>
> >> > self.functionQueue = Queue.Queue()
> >> > self.root = root
> >> > self.timeout = timeout
>
> >> > if(self.root):
> >> > self.pop_function(root)
>
> >> > def pop_function(self, root = None):
>
> >> > try:
> >> > funcArgList = self.functionQueue.get(block = False)
> >> > except Queue.Empty:
> >> > pass
> >> > else:
> >> > try:
> >> > funcArgList[0](*funcArgList[1])
> >> > except:
> >> > try:
> >> > print "Failed to call function", funcArgList[0]
> >> > except:
> >> > print "Failed to call function"
>
> >> > if(root):
> >> > root.after(self.timeout, lambda: self.pop_function
> >> > (self.root))
>
> >> > def add_function(self, function, argList):
>
> >> > try:
> >> > self.functionQueue.put([function, argList])
> >> > except:
> >> > pass
>
> >> > if( __name__ == '__main__'):
>
> >> > import Tkinter
> >> > import thread
>
> >> > text = Tkinter.Text()
> >> > text.pack()
>
> >> > myQueue = functionQueue(text, 50)
>
> >> > def gui_loop():
> >> > try:
> >> > text.mainloop()
> >> > except:
> >> > import os
> >> > os._exit(1)
>
> >> > thread.start_new_thread(text.mainloop, ())
>
> >> > while(True):
> >> > usrInput = raw_input()
>
> >> > if(usrInput == "-1"):
> >> > import os
> >> > os._exit(0)
>
> >> > myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> >> > myQueue.add_function(text.see, ['end'])
>
> >> > [/code]
>
> >> I can make it work over here by putting the UI into the main thread, as
> >> suggested byhttp://effbot.org/zone/tkinter-threads.htm:
>
> >> import Queue
> >> import Tkinter
> >> import threading
>
> >> class FunctionQueue:
> >> # unchanged
>
> >> def input_loop():
> >> while True:
> >> try:
> >> usrInput = raw_input()
> >> except EOFError:
> >> break
> >> myQueue.add_function(text.insert, ['end', usrInput + "\n"])
> >> myQueue.add_function(text.see, ['end'])
> >> myQueue.add_function(text.quit, [])
>
> >> if __name__ == '__main__':
> >> text = Tkinter.Text()
> >> text.pack()
>
> >> myQueue = FunctionQueue(text, 50)
> >> threading.Thread(target=input_loop).start()
> >> text.mainloop()
>
> >> Peter
>
> > Peter, thanks for the suggestion. ?I tried your code exactly on my box
> > and I still get the same results. ?As soon as I run the script and
> > every time I click on the Text box I get tcl::Bgerror ... just like I
> > mentioned above. ?I'm fairly certain that I'm not calling Tkinter
> > functions from any other thread but it's acting as though I am as soon
> > as I create the input thread.
> > If I comment out the input loop thread everything is fine but of
> > course that's not terribly useful as a logging box.
>
> http://bugs.python.org/issue3835
>
> Could tcl have been built without thread support on the failing machines?
>
> Peter

You had it Peter.  I tried the "import pydoc pydoc.gui()" in the bug
report you referenced and the same thing described there occurred.
After recompiling tcl/tk with --threads-enabled and replacing the
slackware default packages with those everything is working as I
expected.  Thanks for the help.


From aahz at pythoncraft.com  Sun Jul  5 11:08:23 2009
From: aahz at pythoncraft.com (Aahz)
Date: 5 Jul 2009 08:08:23 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<mailman.2639.1246802753.8015.python-list@python.org>
Message-ID: <h2qfl7$k87$1@panix3.panix.com>

In article <mailman.2639.1246802753.8015.python-list at python.org>,
Hendrik van Rooyen <mail at microcorp.co.za> wrote:
>
>But wait - maybe if he passes an iterator around - the equivalent of
>for char in input_stream...  Still no good though, unless the next call
>to the iterator is faster than an ordinary python call.

Calls to iterators created by generators are indeed faster than an
ordinary Python call, because the stack frame is already mostly set up.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From nomail at thank.you  Sun Jul  5 11:26:21 2009
From: nomail at thank.you (jack catcher (nick))
Date: Sun, 05 Jul 2009 18:26:21 +0300
Subject: Python and webcam capture delay?
Message-ID: <dC34m.20648$vi5.6555@uutiset.elisa.fi>

Hi,

I'm thinking of using Python for capturing and showing live webcam 
stream simultaneously between two computers via local area network. 
Operating system is Windows. I'm going to begin with VideoCapture 
extension, no ideas about other implementation yet. Do you have any 
suggestions on how short delay I should hope to achieve in showing the 
video? This would be part of a psychological experiment, so I would need 
to deliver the video stream with a reasonable delay (say, below 100ms).


From serverin2000 at yahoo.com  Sun Jul  5 11:56:12 2009
From: serverin2000 at yahoo.com (RAM)
Date: Sun, 5 Jul 2009 08:56:12 -0700 (PDT)
Subject: generation of keyboard events
Message-ID: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>

Hi,

I need to start an external program and pass the keyboard events like
F1,Right arrow key etc to the program..I am trying to use the
subprocess module to invoke the external program. I am able to invoke
but not able to generate the keyboard events and pass them on to the
external progam. Please help me in this because I am a beginner.

regards
Sreerama V


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 12:00:03 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 16:00:03 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
Message-ID: <0260bf8d$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 03:08:16 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> > Yes, it saves a few keystrokes to say "if x:" instead of "if
>> > len(x)==0:" or even "if bool(x):",
>> 
>> It's not about saving keystrokes -- that's a furphy. It's about
>> encapsulation. Objects are in a better position to recognise when they
>> are "something" (true) or "nothing" (false) than you are.
> 
> I don't know what a furphy is, 

Is your Google broken? *wink*

http://en.wikipedia.org/wiki/Furphy


> but I don't accept that "somethingness"
> vs. "nothingness" is the same distinction as truth vs falsehood.

It's the distinction used by Python since the dawn of time. Python only 
grew a bool type a few versions back.


> True
> and False are values in a specific datatype (namely bool), not abstract
> qualities of arbitrary data structures.  

I'm not talking about the constants True and False (nouns), but about 
true and false values (adjectives).


> The idea that the "if"
> statement selects between "somethingness" and "nothingness" rather than
> between True and False is a bogus re-imagining of the traditional
> function of an "if" statement 

There's nothing bogus about it.

Some languages such as Pascal and Java require a special Boolean type for 
if-branches. Other languages, like Forth, C, Lisp and Ruby do not.

http://en.wikipedia.org/wiki/Boolean_data_type


> and has been an endless source of bugs in Python code.


I wonder why these "endless" bugs weren't important enough to be 
mentioned in the rationale to PEP 285:

http://www.python.org/dev/peps/pep-0285/

You'd think something as vital as "if x Considered Harmful" would have 
made it into the PEP, but no. Instead Guido *explicitly* stated that he 
had no intention of forcing `if` to require a bool, describing `if x` as 
the "correct form" and calling scrapping such a feature as "crippling the 
language".

 
> Look how much confusion it causes here in the newsgroup all the time.

The only confusion is that you're causing me. Would you care to link to 
some?



>> "if len(x) == 0" is wasteful. Perhaps I've passed you a list-like
>> iterable instead of a list, and calculating the actual length is O(N).
> 
> That doesn't happen in any of Python's built-in container types.

And if they were the only types possible in Python, that might be 
relevant.


> I
> could see some value to having a generic "is_empty" predicate on
> containers though, to deal with this situation.

We have that already. It's spelled __bool__ or __nonzero__, and it 
applies to any object, not just containers.


> Your iterable could
> support that predicate.  In fact maybe all iterables should support that
> predicate.  They don't (and can't) all support "len".

Iterators are a special case, because in general they can't tell if 
they're exhausted until they try to yield a value.


>> If you write len(x)==0 Python doesn't complain if x is a dict instead
>> of the list you were expecting. Why is it acceptable to duck-type
>> len(x) but not truth-testing?
> 
> I haven't seen the amount of bugs coming from generic "len" as from
> something-vs-nothing confusion.

Again with these alleged bugs.



-- 
Steven


From pm567426 at gmail.com  Sun Jul  5 12:01:30 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 09:01:30 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
Message-ID: <6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com>

Hello again,
This time I have a simple C question!
As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
found PyObject_NEW_VAR in objimpl.h header file. But I can't
understand the last line :( Here's the code:

#define PyObject_NEW_VAR(type, typeobj, n) \
( (type *) PyObject_InitVar( \
      (PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
(n)) ),\
      (typeobj), (n)) )

I know this will replace the PyObject_New_VAR(type, typeobj, n)
everywhere in the code and but I can't understand the last line, which
is just 'typeobj' and 'n'! What do they do? Are they make any sense in
allocation process?


From aahz at pythoncraft.com  Sun Jul  5 12:12:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 5 Jul 2009 09:12:19 -0700
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com>
Message-ID: <h2qjd3$ji7$1@panix3.panix.com>

In article <6f6be2b9-49f4-4db0-9c21-52062d8ea3df at l31g2000yqb.googlegroups.com>,
Pedram  <pm567426 at gmail.com> wrote:
>
>This time I have a simple C question!
>As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
>found PyObject_NEW_VAR in objimpl.h header file. But I can't
>understand the last line :( Here's the code:
>
>#define PyObject_NEW_VAR(type, typeobj, n) \
>( (type *) PyObject_InitVar( \
>      (PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
>(n)) ),\
>      (typeobj), (n)) )
>
>I know this will replace the PyObject_New_VAR(type, typeobj, n)
>everywhere in the code and but I can't understand the last line, which
>is just 'typeobj' and 'n'! What do they do? Are they make any sense in
>allocation process?

Look in the code to find out what PyObject_InitVar() does -- and, more
importantly, what its signature is.  The clue you're missing is the
trailing backslash on the third line, but that should not be required if
you're using an editor that shows you matching parentheses.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From usernet at ilthio.net  Sun Jul  5 12:12:37 2009
From: usernet at ilthio.net (Tim Harig)
Date: Sun, 05 Jul 2009 16:12:37 GMT
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
Message-ID: <Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>

On 2009-07-05, RAM <serverin2000 at yahoo.com> wrote:
> I need to start an external program and pass the keyboard events like
> F1,Right arrow key etc to the program..I am trying to use the
> subprocess module to invoke the external program. I am able to invoke
> but not able to generate the keyboard events and pass them on to the

catb.org/esr/faqs/smart-questions.html

You have told us nothing about the environment where you are trying to
accomplish this.  GUI, CLI, Unix, Windows, etc? So I suggest that you
checkout the curses getch functions.  You can find them in the standard
library documentation at http://docs.python.org.  You should also reference
documentation for the C version in your systems man pages.


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 12:13:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 16:13:30 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
	<hg04m.2790$ze1.2441@news-server.bigpond.net.au>
Message-ID: <0260c2b4$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 11:37:49 +0000, Lie Ryan wrote:

> Neither python's `if` nor `if` in formal logic is about testing True vs.
> False. `if` in python and formal logic receives a statement. The
> statement must be evaluatable to True or False, but does not have to be
> True or False themselves. It just happens that True evaluates to True
> and False evaluates to False.

I think your explanation is a little confused, or at least confusing.

`if` implements a two-way branch. Some languages, like Pascal and Java, 
requires the switch value to take one of two specific enumerable values 
conventionally spelled TRUE and FALSE (modulo variations in case).

Other languages don't require specific enumerable values, and instead 
accept (e.g.) any integer, or any object, with rules for how to interpret 
such values in such a context. Forth, for example, branches according to 
whether the word on the stack is zero or non-zero: "nothing" or 
"something". Lisp branches according to empty list or non-empty list: 
"nothing" or "something" again.

Other languages, like Ruby, have less intuitive rules. That's their 
problem.



-- 
Steven


From emile at fenx.com  Sun Jul  5 12:19:48 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 05 Jul 2009 09:19:48 -0700
Subject: generation of keyboard events
In-Reply-To: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
Message-ID: <h2qjr9$6k3$1@ger.gmane.org>

On 7/5/2009 8:56 AM RAM said...
> Hi,
> 
> I need to start an external program and pass the keyboard events like
> F1,Right arrow key etc to the program..I am trying to use the
> subprocess module to invoke the external program. I am able to invoke
> but not able to generate the keyboard events and pass them on to the
> external progam.

If you're on *nix, search for python and expect and you'll find 
something based apps -- I'm not sure what you do for GUIs. On windows, 
I'm sure there are ways of doing this with the win32 extensions, but I 
commonly use msched from www.mjtnet.com.  I create msched scripts from 
within python and use subprocess to invoke msched and execute the python 
generated script.

HTH,

Emile


> Please help me in this because I am a beginner.
> 
> regards
> Sreerama V



From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 12:20:32 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 05 Jul 2009 16:20:32 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<pYKdne6TVpFHjtDXnZ2dnUVZ_sednZ2d@giganews.com>
	<f778eb7d-7ed3-43c9-aef6-56b12c575b2a@y7g2000yqa.googlegroups.com>
	<7x4otu1rkw.fsf@ruckus.brouhaha.com>
	<a83acc32-77ab-43e0-98a4-e52ca1c05bcb@j32g2000yqh.googlegroups.com>
	<7x3a9egy9j.fsf@ruckus.brouhaha.com>
	<2f0a035e-ad2e-4364-a224-d4e8c1e8110a@j32g2000yqh.googlegroups.com>
	<7xhbxtjxtn.fsf@ruckus.brouhaha.com>
	<025eaa4f$0$20657$c3e8da3@news.astraweb.com>
	<7x1vovxohy.fsf@ruckus.brouhaha.com>
Message-ID: <0260c45a$0$20657$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 06:12:25 -0700, Paul Rubin wrote:

>> There are three natural approaches to (say) re.search() for dealing
>> with failure:
>> 
>> (1) return a sentinel value like None; (2) return a matchobject which
>> tests False; (3) raise an exception.
> 
> 4. Have re.search return a bool and possible matchobject separately:
> 
>    put_match_here = []
>    if re.search(pat, s, target=put_match_here):
>       do_something_with(put_match_here[0])

Wow. I never for the life of me thought I'd see an experienced Python 
programmer re-implement Pascal's VAR parameters.

That is... hideous. Returning a (flag, matchobject) tuple is the height 
of beauty in comparison.



-- 
Steven


From pm567426 at gmail.com  Sun Jul  5 12:32:41 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 09:32:41 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com> 
	<h2qjd3$ji7$1@panix3.panix.com>
Message-ID: <179f64f8-6528-4953-88b1-4096d5907cbe@p29g2000yqh.googlegroups.com>

On Jul 5, 8:12?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <6f6be2b9-49f4-4db0-9c21-52062d8ea... at l31g2000yqb.googlegroups.com>,
>
>
>
> Pedram ?<pm567... at gmail.com> wrote:
>
> >This time I have a simple C question!
> >As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
> >found PyObject_NEW_VAR in objimpl.h header file. But I can't
> >understand the last line :( Here's the code:
>
> >#define PyObject_NEW_VAR(type, typeobj, n) \
> >( (type *) PyObject_InitVar( \
> > ? ? ?(PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
> >(n)) ),\
> > ? ? ?(typeobj), (n)) )
>
> >I know this will replace the PyObject_New_VAR(type, typeobj, n)
> >everywhere in the code and but I can't understand the last line, which
> >is just 'typeobj' and 'n'! What do they do? Are they make any sense in
> >allocation process?
>
> Look in the code to find out what PyObject_InitVar() does -- and, more
> importantly, what its signature is. ?The clue you're missing is the
> trailing backslash on the third line, but that should not be required if
> you're using an editor that shows you matching parentheses.
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "as long as we like the same operating system, things are cool." --piranha

No, they wrapped the 3rd line!

I'll show you the code in picture below:
http://lh3.ggpht.com/_35nHfALLgC4/SlDVMEl6oOI/AAAAAAAAAKg/vPWA1gttvHM/s640/Screenshot.png

As you can see the PyObject_MALLOC has nothing to do with typeobj and
n in line 4.


From pm567426 at gmail.com  Sun Jul  5 12:34:37 2009
From: pm567426 at gmail.com (Pedram)
Date: Sun, 5 Jul 2009 09:34:37 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<6f6be2b9-49f4-4db0-9c21-52062d8ea3df@l31g2000yqb.googlegroups.com> 
	<h2qjd3$ji7$1@panix3.panix.com>
	<179f64f8-6528-4953-88b1-4096d5907cbe@p29g2000yqh.googlegroups.com>
Message-ID: <5a0b1063-ae2b-4229-b040-4904b4d01077@b15g2000yqd.googlegroups.com>

On Jul 5, 8:32?pm, Pedram <pm567... at gmail.com> wrote:
> On Jul 5, 8:12?pm, a... at pythoncraft.com (Aahz) wrote:
>
>
>
> > In article <6f6be2b9-49f4-4db0-9c21-52062d8ea... at l31g2000yqb.googlegroups.com>,
>
> > Pedram ?<pm567... at gmail.com> wrote:
>
> > >This time I have a simple C question!
> > >As you know, _PyLong_New returns the result of PyObject_NEW_VAR. I
> > >found PyObject_NEW_VAR in objimpl.h header file. But I can't
> > >understand the last line :( Here's the code:
>
> > >#define PyObject_NEW_VAR(type, typeobj, n) \
> > >( (type *) PyObject_InitVar( \
> > > ? ? ?(PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),
> > >(n)) ),\
> > > ? ? ?(typeobj), (n)) )
>
> > >I know this will replace the PyObject_New_VAR(type, typeobj, n)
> > >everywhere in the code and but I can't understand the last line, which
> > >is just 'typeobj' and 'n'! What do they do? Are they make any sense in
> > >allocation process?
>
> > Look in the code to find out what PyObject_InitVar() does -- and, more
> > importantly, what its signature is. ?The clue you're missing is the
> > trailing backslash on the third line, but that should not be required if
> > you're using an editor that shows you matching parentheses.
> > --
> > Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> > "as long as we like the same operating system, things are cool." --piranha
>
> No, they wrapped the 3rd line!
>
> I'll show you the code in picture below:http://lh3.ggpht.com/_35nHfALLgC4/SlDVMEl6oOI/AAAAAAAAAKg/vPWA1gttvHM...
>
> As you can see the PyObject_MALLOC has nothing to do with typeobj and
> n in line 4.

Oooooh! What a mistake! I got it! they're Py_Object_InitVar
parameters.
Sorry and Thanks!


From lie.1296 at gmail.com  Sun Jul  5 12:43:35 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 05 Jul 2009 16:43:35 GMT
Subject: question of style
In-Reply-To: <0260c2b4$0$20657$c3e8da3@news.astraweb.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<025ff51b$0$20657$c3e8da3@news.astraweb.com>	<7xfxdbk61a.fsf@ruckus.brouhaha.com>	<02605e46$0$20657$c3e8da3@news.astraweb.com>	<7xy6r34f3j.fsf@ruckus.brouhaha.com>	<hg04m.2790$ze1.2441@news-server.bigpond.net.au>
	<0260c2b4$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <XK44m.2824$ze1.1582@news-server.bigpond.net.au>

Steven D'Aprano wrote:
> On Sun, 05 Jul 2009 11:37:49 +0000, Lie Ryan wrote:
> 
>> Neither python's `if` nor `if` in formal logic is about testing True vs.
>> False. `if` in python and formal logic receives a statement. The
>> statement must be evaluatable to True or False, but does not have to be
>> True or False themselves. It just happens that True evaluates to True
>> and False evaluates to False.
> 
> I think your explanation is a little confused, or at least confusing.

Indeed, partially because I said "statement" when I really meant
"expression".

> Other languages don't require specific enumerable values, and instead 
> accept (e.g.) any integer, or any object, with rules for how to interpret 
> such values in such a context. 

That was what I was wanting to say, except that I stretched that to
formal logic (mathematical logic). Even in formal logic `if` receives
any arbitrary expression that can be -- according to certain rules --
interpreted as True or False (i.e. the expressions themselves are not
required to be a boolean value).

The conclusion is python's `if` does not deviate from `if`'s semantic in
mathematical sense.


From piet at cs.uu.nl  Sun Jul  5 13:28:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 05 Jul 2009 19:28:35 +0200
Subject: Determining if a function is a method of a class within
	a	decorator
References: <4A4963E9.30202@ilm.com> <h2bpu2$ki$1@ger.gmane.org>
	<mailman.2349.1246327265.8015.python-list@python.org>
Message-ID: <m2y6r3doos.fsf@cs.uu.nl>

>>>>> David Hirschfield <davidh at ilm.com> (DH) wrote:

>DH> Yeah, it definitely seems like having two separate decorators is the
>DH> solution. But the strange thing is that I found this snippet after some
>DH> deep googling, that seems to do something *like* what I want, though I
>DH> don't understand the descriptor stuff nearly well enough to get what's
>DH> happening:

>DH> http://stackoverflow.com/questions/306130/python-decorator-makes-function-forget-that-it-belongs-to-a-class

>DH> answer number 3, by ianb. It seems to indicate there's a way to introspect
>DH> and determine the class that the function is going to be bound to...but I
>DH> don't get it, and I'm not sure it's applicable to my case.

>DH> I'd love an explanation of what is going on in that setup, and if it isn't
>DH> usable for my situation, why not?

What that example does is not getting the name of the class in the
decorator, but in the bound method that is the result of the decorator
when that method is called. This is just done by asking for the class of
the self parameter. Actually they even don't do that in that example but
it could have been done. Note also that there is an error in the code:
keyargs should be kw.

There is also something special in that code: it uses the descriptor
protocol. This is necessary for a method. The descriptor protocol for
methods defines a __get__ method that transforms the unbound method into
a bound method. That code uses this to decorate the generated bound method
object instead of decorating the unbound method.

A side effect of doing the class detection at call time is that you get
the name of the subclass if you use the method on an instance of the
subclass, not the name of the class that the method was defined in:

class D(C):
     pass

D().f(1, 2) will talk about class D, not class C.

So if you would like to do something special for bound methods the
__get__ might be the proper place to do it.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From a0046088 at airmail.net  Sun Jul  5 14:20:26 2009
From: a0046088 at airmail.net (wwwayne)
Date: Sun, 05 Jul 2009 12:20:26 -0600
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
Message-ID: <3in15557eu33n494hh3lvmcnssujl2ueds@4ax.com>

On Fri, 03 Jul 2009 14:34:58 GMT, Alan G Isaac <alan.isaac at gmail.com>
wrote:

>On 7/3/2009 10:05 AM kj apparently wrote:

=== 8< ===

>2.
>from scipy.optimize import bisect
>def _binary_search(lo, hi, func, target, epsilon):
>    def f(x): return func(x) - target
>    return bisect(f, lo, high, xtol=epsilon)
>
>3. If you don't want to use SciPy (why?), have them
>implement http://en.wikipedia.org/wiki/Bisection_method#Pseudo-code
>to produce their own `bisect` function.

Of course this isn't really pseudo-code, it's VB code with quite poor
comments: 

    'Bisection Method
 
   'Start loop
    Do While (abs(right - left) > 2*epsilon)
 
      'Calculate midpoint of domain
      midpoint = (right + left) / 2
 
      'Find f(midpoint)
      If ((f(left) * f(midpoint)) > 0) Then
        'Throw away left half
        left = midpoint
      Else
        'Throw away right half
        right = midpoint
      End If
    Loop
    Return (right + left) / 2

and even just throwing away the VB code and leaving the comments does
not give a good algorithm:

    'Bisection Method
 
    'Start loop
 
      'Calculate midpoint of domain
 
      'Find f(midpoint)

        'Throw away left half

        'Throw away right half

A much  better approach to teaching introductory programming in any
language at almost any level is to incorporate some "top down problem
solving", including writing a method of solution (algorithm) in some
reasonably well-defined pseudo-code that can be easily elaborated and
translated into one's target language (and, peferably, some
reasonable-sized subset of related languages). This pseudo-code should
then become comments (or equivalent) for the students to convert to
real code, as in:

Algorithm bisect (f, left, right, epsilon):

# Bisection Method to find a root of a real continuous function f(x):
#    Assume f(x) changes sign between f(left) and f(right) and
#       we want a value not further than epsilon from a real root.
#    Begin with the domain left...right.

# While the absolute value of (left - right) exceeds 2*epsilon:

	# Calculate the midpoint, mid,  of the domain.

	# If the product of f(left) and f(mid) is positive:

		# Set left to mid;

	# Otherwise:

		# Set right to mid.

# Return the midpoint of left...right.

===
And adapting this approach to kj's case is straightforward.

Of course, what consitutes a suitable vocabulary and syntax for an
algorithm pseudo-code language depends upon the target language(s),
the tastes of the instructor, and the point in the lesson or course.
My choice is for python+COBOL (as above) initially, soon incorporating
the usual arithmetic and relational operators (and how soon and how
many at once depends upon the level of the students: for an
introductory university/college course in Computer Science or
equivalent, where everyone should have a reasonable background in
mathemtics notation as a prerequisite, this should be very soon and
quite fast), arrays and subscripting, etc.

But if we were to write this algorithm or kj's in python-like
pseudo-code it would already *be* python codeor very close to
it--which is why we should teach intorductory programming in python.
Very soon students would be writing algorithms that required very
little elaboration to be programs.

But without including suitable problem solving and psudo-code
algorithm writing there will soon come a time or an example where
students are trying to think in code instead of in their natural
language and don't have the experience and repertoire to be able to do
that well.

I hope that's not too pedantic or AR?

wayne

>hth,
>Alan Isaac


From dotancohen at gmail.com  Sun Jul  5 14:32:56 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Sun, 5 Jul 2009 21:32:56 +0300
Subject: A C++ user's introduction to Python: a really good read
Message-ID: <880dece00907051132p117ca7e0sf5774d1eb5014c64@mail.gmail.com>

Here is a C++ KDE programer's take on Python:
http://majewsky.wordpress.com/2009/07/04/python-experiences-or-why-i-like-c-more/

Good read.

-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From nick.m.daly at gmail.com  Sun Jul  5 14:48:06 2009
From: nick.m.daly at gmail.com (Nick Daly)
Date: Sun, 5 Jul 2009 13:48:06 -0500
Subject: Method to separate unit-test methods and data?
In-Reply-To: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
References: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
Message-ID: <be8f57070907051148x52ee305ch905c79bb0d59d983@mail.gmail.com>

Hi,

I was wondering if it's possible / if there are any simple methods
known of storing unit-test functions and their data in separate files?

Perhaps this is a strange request, but it does an excellent job of
modularizing code. ?As far as revision control goes, it makes it
easier to discern between new or changed test cases, and changes in
the test data.

I've worked through this idea a bit and actually have a nearly working
model. ?For example, when testing a class, I have a test module, which
contains a class for testing each method of the class. ?This allows me
to generalize each method's parameters into each class, which can then
be overridden by the config file's data, something like as follows
(with a really arbitrary example, Python 2.5 code):


Demo code (midpoint.py):
=======================

class Midpoint(object):

? ?def __init__(self, a, b):
? ? ? ?self.a = a
? ? ? ?self.b = b

? ?def mid():
? ? ? ?return (self.a + self.b) / 2.0

? ?def sum()
? ? ? ?return (self.a + self.b)



Testing Code (test_Midpoint.py):
===============================

import unittest
import midpoint
import sys, ConfigParser as configparser


# set up the config file that overrides each class's data
config = configparser.SafeConfigParser()
config.read(sys.argv[0])


class test_Midpoint_mid(unittest.TestCase):
? ?def __init__(self):

? ? ? ?# default testing values
? ? ? ?self.none_values = ((None, 1),
? ? ? ? ? ? ? ? ? ? ? ? ? ?(0, None))

? ? ? ?# override the default values with the config file values
? ? ? ?for key, value in config.items(self.__class__.__name__):
? ? ? ? ? ?if value:
? ? ? ? ? ? ? ?setattr(self, key, value)


? ?# a few tests of the method
? ?def test_rejectNone(self):
? ? ? ?for tests in self.none_values:
? ? ? ? ? ?self.assertRaises(TypeError,
? ? ? ? ? ? ? ?midpoint.Midpoint(tests[0], tests[1]).mid)

# and repeat the concept for class test_Midpoint_sum



Config Code (test_Midpoint.cfg):
==============================

# override the default values of the test class's members

[test_Midpoint_mid]
none_values = ((-1, None),
? ? ? ? ? ? ? (None, -12.8))



What I haven't yet figured out how to do though, is properly override
the default class member values with values from the config file. ?The
config file's data is loaded as a string instead of as a list, as I'd
want. ?This causes all the tests to fail, as while none_values needs
to be interpreted as a list, it is instead understood as:

" ((-1, None),\n ? ? ? ? ? ? ? (None, -12.8))"

Does anyone have any solutions for these problems? ?First, is there a
known and simple way to separate unit-test data and methods into
separate files? ?Secondly, if not, is there a simple way to convert
strings into other base types, like lists, dictionaries, and so forth?
Or, am I going to have to write my own list-parsing methods? ?Would
pickling help? ?I haven't yet had a chance to look into if or how that
would work... ?If there's anything else I can clarify about this
request, feel free to let me know.

Thanks for any help you can provide,
Nick


From maymunbeyin at gmail.com  Sun Jul  5 14:59:01 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 11:59:01 -0700 (PDT)
Subject: Creating alot of class instances?
Message-ID: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>

Hi

I am new to Python classes and trying to figure out this particular
issue here. I will need to create instances of a class. But at the
moment I do not know how many instances I will end up having, in every
case it might be different. Most of the documents I read makes this
simpl class-student analogy to explain python classes which is fine.
But in those examples the number and the names of the instances were
known and limited.

I will be querying some data and create class instances based on the
data I gather. But the problem as I mentioned is that I do not know
the names and the number of the end class instances. They will be
based on the content of the data. So how can I create class instances
within a loop and when the loop is done how can I figure out the list
of instances via class membership?  I can track the names by
introducing another list but I want to understand the class side of
things.

The solution might be dead simple but I just cannot figure out at the
moment.

For example this is what I need in the simplest form

class myclass():
 def __init__(self,name):
 self.name=name

for count,data in enumerate(some list):
  instance_count=myclass()
  instance_count.name=data

print instances


thanks





From tjreedy at udel.edu  Sun Jul  5 15:09:33 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 05 Jul 2009 15:09:33 -0400
Subject: question of style
In-Reply-To: <7xy6r34f3j.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<025ff51b$0$20657$c3e8da3@news.astraweb.com>	<7xfxdbk61a.fsf@ruckus.brouhaha.com>	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
Message-ID: <h2qtpe$v2f$1@ger.gmane.org>

Paul Rubin wrote:

> I don't know what a furphy is, but I don't accept that "somethingness"
> vs. "nothingness" is the same distinction as truth vs falsehood.  True
> and False are values in a specific datatype (namely bool), not
> abstract qualities of arbitrary data structures.  The idea that the
> "if" statement selects between "somethingness" and "nothingness"
> rather than between True and False is a bogus re-imagining of the
> traditional function of an "if" statement and has been an endless
> source of bugs in Python code.  Look how much confusion it causes here
> in the newsgroup all the time.

You appear to be confusing a specific interpretation of an abstraction 
with the abstraction itself. Or perhaps better, you seem to be confusing 
a specific example of a general process with the general process.

A boolean variable is a variable that is in one of two states -- a 
binary variable -- a variable that carries one bit of information. The 
two states are the marked state and the unmarked or default state. Which 
is to say, when we draw a distinction to distinguish two states, we mark 
one of them to distinguish one from the other. The if statement tests 
whether an object is in the marked state (or not).

Truth and falsity of propositions are one possible interpretation of 
marked and unmarked, giving us propositional logic.  But they are only 
one of many. So are in and out of a particular class and member or not 
of a set or subclass or not of a set, giving us class and set logic. So 
are closed and open, said of gates or switches, or on and off, giving us 
switching logic. So are non-zero and zero, said of numbers. Or done and 
not done, said of an algorithmic process.

Counts 0 and 1, and their representations '0' and '1', taken in 
themselves, are as good as any distinct pair as a pair of labels for the 
two distinct states. They have some computational advantages, including 
making it easy to count the number of objects in a collection in the 
marked state (and, given the total number, the number in the unmarked 
state). They have one disadvantage, though. If I say 'x = 1', do I mean 
1 versus 0 or 1 versus all possible ints? Similarly, If 'print(x)' 
prints 1, does it mean 1 versus 0 or 1 versus all other ints? 
Recognizing this, Guido decided to subclass them and give them alternate 
names. He could have chosen 'Marked' and 'Unmarked', or any of several 
other pairs, but did choose the conventional 'True' and 'False', 
referring to the common propositional interpretation. However, he 
specifically disclaimed any intention to restrict 'if' to testing 
specific logic propositions, as opposed to the general proposition 
'object is in the marked state'.

Terry Jan Reedy



From andreengels at gmail.com  Sun Jul  5 15:20:38 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sun, 5 Jul 2009 21:20:38 +0200
Subject: Creating alot of class instances?
In-Reply-To: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
Message-ID: <6faf39c90907051220o5b2adebbnae1136d987209a5a@mail.gmail.com>

On 7/5/09, kk <maymunbeyin at gmail.com> wrote:

>  I am new to Python classes and trying to figure out this particular
>  issue here. I will need to create instances of a class. But at the
>  moment I do not know how many instances I will end up having, in every
>  case it might be different. Most of the documents I read makes this
>  simpl class-student analogy to explain python classes which is fine.
>  But in those examples the number and the names of the instances were
>  known and limited

That's no problem. The only limit to the number of instances of a
class you can create is your memory - and not even that if you don't
need to 'keep' the instances.

>  I will be querying some data and create class instances based on the
>  data I gather. But the problem as I mentioned is that I do not know
>  the names and the number of the end class instances. They will be
>  based on the content of the data. So how can I create class instances
>  within a loop and when the loop is done how can I figure out the list
>  of instances via class membership?  I can track the names by
>  introducing another list but I want to understand the class side of
>  things.
>
>  The solution might be dead simple but I just cannot figure out at the
>  moment.
>
>  For example this is what I need in the simplest form
>
>  class myclass():
>   def __init__(self,name):
>   self.name=name
>
>  for count,data in enumerate(some list):
>   instance_count=myclass()
>   instance_count.name=data
>
>  print instances

Okay, to solve your problem, we add a list containing all the instances:

class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for count,data in enumerate(some list):
    instance_count=myclass()
    instance_count.name=data
    instances.append(instance_count)

print instances

=============================================

However, that won't work because myclass has an __init__ with 2
attributes, so you will have to call it using an attribute:

class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for count,data in enumerate(some list):
    instance_count=myclass(data)
    instances.append(instance_count)

print instances

=============================================

This works, but it can be done better:

First we notice that count is not used at all, so why create it?


class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for data in some list:
    instance_count=myclass(data)
    instances.append(instance_count)

print instances

=============================================

Then, the variable instance_count is created once, then used in the
next line. We can do that at once:


class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for data in some list:
    instances.append(myclass(data))

print instances

====================

Finally, "print instances" does not give very nice looking
information, so I would change this to:

class myclass():
    def __init__(self,name):
        self.name=name

instances = []

for data in some list:
    instances.append(myclass(data))

print (instance.name for instance in instances)

-- 
Andr? Engels, andreengels at gmail.com


From python.list at tim.thechases.com  Sun Jul  5 15:21:35 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sun, 05 Jul 2009 14:21:35 -0500
Subject: Creating alot of class instances?
In-Reply-To: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
Message-ID: <4A50FD3F.7080105@tim.thechases.com>

> The solution might be dead simple but I just cannot figure out at the
> moment.
> 
> For example this is what I need in the simplest form
> 
> class myclass():
>  def __init__(self,name):
>  self.name=name
> 
> for count,data in enumerate(some list):
>   instance_count=myclass()
>   instance_count.name=data
> 
> print instances

Sounds like a use for a list:

   instances = []
   for count, data in enumerate(some_list):
     # 1) camel-case is preferred for classnames
     # 2) since your __init__() expects the name
     # pass it in, instead of setting it later
     instance = MyClass(data)
     instances.append(instance)

This can be written in a slightly more condensed-yet-readable 
list-comprehension form as:

   instances = [MyClass(data) for data in some_list]

You then have a list/array of instances you can print:

   print instances

or pick off certain items from it:

   print instances[42]

-tkc





From martin at v.loewis.de  Sun Jul  5 15:23:50 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 05 Jul 2009 21:23:50 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <4A50FDC6.1040604@v.loewis.de>

> This is a good test for Python implementation bottlenecks.  Run
> that tokenizer on HTML, and see where the time goes.

I looked at it with cProfile, and the top function that comes up
for a larger document (52k) is
...validator.HTMLConformanceChecker.__iter__.

This method dispatches various validation routines, and it computes
the method names from the input over and over again, doing lots
of redundant string concatenations. It also capitalizes the element
names, even though the spelling in the original document is probably
not capitalized (but either upper-case or lower case).

In my patch below, I create a dictionary of bound methods, indexed
by (syntax) type and name, following the logic of falling back to
just type-based validation if no type/name routine exists. However,
in order to reduce the number of dictionary lookups, it will also
cache type/name pairs (both in the original spelling, and the
capitalized spelling), so that subsequent occurrences of the same
element will hit the method cache.

With this simple optimization, I get a 20% speedup on my test
case. In my document, there are no attributes - the same changes
should be made to attribute validation routines.

I don't think this has anything to do with the case statement.

Regards,
Martin

-------------- next part --------------
A non-text attachment was scrubbed...
Name: methodlookup.diff
Type: text/x-patch
Size: 2837 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090705/1dcb8735/attachment-0001.bin>

From maymunbeyin at gmail.com  Sun Jul  5 15:54:58 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 12:54:58 -0700 (PDT)
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2648.1246821707.8015.python-list@python.org>
Message-ID: <0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>

Hi

Thank you soo much for speedy and in detailed help. Your replies
really cleared out most of the cloud for me. I have one last issue to
resolve which is something I did not articulate properly, I realize
now. The last issue is actually automatically naming the instances.
The reason I was using the "instance_count" is for enumerating the
actual name of an instance.

For example lets say I have

class MyMaterials:

and my instances might need to look like

material_01
material_02
or
light_01
light_02
or
Mesh_01
Mesh_02 etc

I will need to get the base names from the "some list" and create the
names accordingly from the list array.

Basically I also need to generate the instance names based on the some
list. For example some_list[2] might denote a name for the instance.

I will study the sampled codes in depth now. Maybe you have answered
the naming issue as well, if so please frgove the noise.

thanks






From vasudevram at gmail.com  Sun Jul  5 16:14:31 2009
From: vasudevram at gmail.com (vasudevram)
Date: Sun, 5 Jul 2009 13:14:31 -0700 (PDT)
Subject: XML(JSON?)-over-HTTP: How to define API?
References: <mailman.2520.1246573083.8015.python-list@python.org> 
	<7b5somF21peceU1@mid.uni-berlin.de>
Message-ID: <5328d134-5fb0-4a0f-b24b-86deeeaf97aa@i4g2000prm.googlegroups.com>

On Jul 3, 1:11?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Allen Fowler schrieb:
>
>
>
>
>
>
>
> >> I have an (in-development) python system that needs to shuttle events / requests
> >> around over the network to other parts of itself. ? It will also need to
> >> cooperate with a .net application running on yet a different machine.
>
> >> So, naturally I figured some sort of HTTP event / RPC type of would be a good
> >> idea?
>
> >> Are there any modules I should know about, or guidelines I could read, that
> >> could aid me in the design of the API? ? ?
>
> > To clarify:
>
> > Each message would be <1KB of data total, and consist of some structured object containing strings, numbers, dates, etc.
>
> > For instance there would be an "add user" request that would contain one or more User objects each having a number of properties like:
>
> > - Full Name
> > - Username
> > - Password
> > - Email addresses (a variable length array)
> > - Street Address line1
> > - Street Address line1
> > - Street Address line1
> > - City
> > - State
> > - Zip
> > - Sign Up Date
>
> > .... and so on.
>
> > Since I need to work with other platforms, pickle is out... ?what are the alternatives? ?XML? JSON?
>
> > How should I formally define each of the valid messages and objects?
>
> > Thank you,
>
> Use XMLRPC. Implementations for both languages are available. There is
> no need for formal spec - which is a good thing. You just call the
> server, and it works.
>
> Diez

I second the suggestion of Diez to use XML-RPC. Very simple to learn
and use. Supports structs (as method arguments and method return
values) which can consist of other data types bundled together, also
supports arrays. Just check whether .NET supports XML-RPC.



From ricli85 at gmail.com  Sun Jul  5 16:38:50 2009
From: ricli85 at gmail.com (Rickard Lindberg)
Date: Sun, 5 Jul 2009 22:38:50 +0200
Subject: Creating alot of class instances?
In-Reply-To: <0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2648.1246821707.8015.python-list@python.org>
	<0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>
Message-ID: <890d8ab70907051338p2eaac716qe96f3a1953d4696c@mail.gmail.com>

> Thank you soo much for speedy and in detailed help. Your replies
> really cleared out most of the cloud for me. I have one last issue to
> resolve which is something I did not articulate properly, I realize
> now. The last issue is actually automatically naming the instances.
> The reason I was using the "instance_count" is for enumerating the
> actual name of an instance.
>
> For example lets say I have
>
> class MyMaterials:
>
> and my instances might need to look like
>
> material_01
> material_02
> or
> light_01
> light_02
> or
> Mesh_01
> Mesh_02 etc

If you do not know how many instances you are going to create from the
beginning, there is no way for you to know which of the instances you mentioned
above will get created. So having names for all of the instances will not help
you since you will never know what names are "safe" to use.

On the other hand, if you have all instances in a list, you can refer to them
by index and you know exactly how many of them you have.

If you would like to get instances by some name you gave to them, maybe
something like this will work:

def get_instance(name):
    for instance in instance_list:
        if instance.name == name:
            return instance
    return None

Note that this might very well return None if no instance with that particular
name was found.

-- 
Rickard Lindberg


From no.email at please.post  Sun Jul  5 16:42:41 2009
From: no.email at please.post (kj)
Date: Sun, 5 Jul 2009 20:42:41 +0000 (UTC)
Subject: memoization module?
Message-ID: <h2r381$q5l$1@reader1.panix.com>



Is there a memoization module for Python?  I'm looking for something
like Mark Jason Dominus' handy Memoize module for Perl.

TIA!

kj



From l.mastrodomenico at gmail.com  Sun Jul  5 16:50:30 2009
From: l.mastrodomenico at gmail.com (Lino Mastrodomenico)
Date: Sun, 5 Jul 2009 22:50:30 +0200
Subject: memoization module?
In-Reply-To: <h2r381$q5l$1@reader1.panix.com>
References: <h2r381$q5l$1@reader1.panix.com>
Message-ID: <cc93256f0907051350i5ebbd9eew321e64ea19ebe489@mail.gmail.com>

2009/7/5 kj <no.email at please.post>:
> Is there a memoization module for Python? ?I'm looking for something
> like Mark Jason Dominus' handy Memoize module for Perl.

Check out the "memoized" class example here:

  <http://wiki.python.org/moin/PythonDecoratorLibrary#Memoize>

-- 
Lino Mastrodomenico


From python.list at tim.thechases.com  Sun Jul  5 17:07:45 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sun, 05 Jul 2009 16:07:45 -0500
Subject: Creating alot of class instances?
In-Reply-To: <890d8ab70907051338p2eaac716qe96f3a1953d4696c@mail.gmail.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>	<mailman.2648.1246821707.8015.python-list@python.org>	<0bbb2017-7ded-43cb-88cc-81703a2b02d3@y7g2000yqa.googlegroups.com>
	<890d8ab70907051338p2eaac716qe96f3a1953d4696c@mail.gmail.com>
Message-ID: <4A511621.9050101@tim.thechases.com>

>> For example lets say I have
>>
>> class MyMaterials:
>>
>> and my instances might need to look like
>>
>> material_01
>> material_02
>> or
>> light_01
>> light_02
>> or
>> Mesh_01
>> Mesh_02 etc
> 
> If you do not know how many instances you are going to create from the
> beginning, there is no way for you to know which of the instances you mentioned
> above will get created. So having names for all of the instances will not help
> you since you will never know what names are "safe" to use.
> 
> On the other hand, if you have all instances in a list, you can refer to them
> by index and you know exactly how many of them you have.
> 
> If you would like to get instances by some name you gave to them, maybe
> something like this will work:
> 
> def get_instance(name):
>     for instance in instance_list:
>         if instance.name == name:
>             return instance
>     return None

Another option might be to use a counter in the class that keeps 
track of the number of instances:

   class MyMaterial:
     instances = 0
     def __init__(self, name):
       self.name = name
       self.instance = MyMaterial.instances
       MyMaterial.instances += 1
     def __str__(self):
       return "%s_%02i" % (self.name, self.instance)

   m = MyMaterial("Brick")
   print m
   # "Brick_00"
   print repr([MyMaterial("Stone") for _ in range(5)])
   # "[Stone_01, Stone_02, Stone_03, Stone_04, Stone_05]"

It's not thread-safe, but it may do the trick.

-tkc





From lists at cheimes.de  Sun Jul  5 17:42:41 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sun, 05 Jul 2009 23:42:41 +0200
Subject: Creating alot of class instances?
In-Reply-To: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
Message-ID: <4A511E51.9030408@cheimes.de>

kk wrote:
> I will be querying some data and create class instances based on the
> data I gather. But the problem as I mentioned is that I do not know
> the names and the number of the end class instances. They will be
> based on the content of the data. So how can I create class instances
> within a loop and when the loop is done how can I figure out the list
> of instances via class membership?  I can track the names by
> introducing another list but I want to understand the class side of
> things.

Do you need an exact number or just a rough statistic? In order to
estimate the number of instances you can query the reference count of
the class. Since every instance usually increases the reference count by
one it provides a good overview. Note that lots of other things like
imports increase the reference count, too.

>>> import sys
>>> class Example(object):
...     pass
...
>>> sys.getrefcount(Example)
5
>>> examples = list(Example() for i in range(10))
>>> examples
[<__main__.Example object at 0x7f2e5cd61110>, <__main__.Example object
at 0x7f2e5cd61150>, <__main__.Example object at 0x7f2e5cd61190>,
<__main__.Example object at 0x7f2e5cd611d0>, <__main__.Example object at
0x7f2e5cd61210>, <__main__.Example object at 0x7f2e5cd61250>,
<__main__.Example object at 0x7f2e5cd61390>, <__main__.Example object at
0x7f2e5cd613d0>, <__main__.Example object at 0x7f2e5cd61410>,
<__main__.Example object at 0x7f2e5cd61450>]
>>> sys.getrefcount(Example)
15


From rhodri at wildebst.demon.co.uk  Sun Jul  5 17:47:25 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 05 Jul 2009 22:47:25 +0100
Subject: pep 8 constants
In-Reply-To: <4A4E1B2F.2000700@mrabarnett.plus.com>
References: <mailman.7174.1231915778.3487.python-list@python.org>
	<49a50517$0$3567$426a74cc@news.free.fr> <4A477991.4050109@harvee.org>
	<op.uv89h1xqa8ncjz@gnudebst> <4A484C07.9050800@harvee.org>
	<4A48A495.7040504@tim.thechases.com> <4A48E307.50804@harvee.org>
	<4A49E232.6090101@tim.thechases.com>
	<mailman.2392.1246375713.8015.python-list@python.org>
	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>
	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>
	<4A4E135E.5090400@harvee.org> <4A4E1B2F.2000700@mrabarnett.plus.com>
Message-ID: <op.uwl6tbzla8ncjz@gnudebst>

On Fri, 03 Jul 2009 15:52:31 +0100, MRAB <python at mrabarnett.plus.com>  
wrote:

> Eric S. Johansson wrote:
>> Horace Blegg wrote:
>>> I've been kinda following this. I have a cousin who is permanently  
>>> wheel
>>> chair bound and doesn't have perfect control of her hands, but still
>>> manages to use a computer and interact with society. However, the
>>> idea/thought of disabled programmers was new to me/hadn't ever occurred
>>> to me.
>>>
>>> You say that using your hands is painful, but what about your feet?
>>> Wouldn't it be possible to rig up some kind of foot peddle for
>>> shift/caps lock? Kinda like the power peddle used with sowing machines,
>>> so the hands are free to hold fabric.
>>>
>>> I don't mean this in a condescending manor, and I apologize if you take
>>> it as such. I'm genuinely curious if you think something like this  
>>> could
>>> work.
>>>
>>> The way I was envisioning it working last night (and I haven't the
>>> faintest clue how SR works, nor have I ever used SR) was that you would
>>> hit the foot peddle, which would tell the SR program to capitalize the
>>> first letter of the next word (a smart shift, basically, so you don't
>>> end up doing something like ... WONderland -or- "stocks are up 1,0))%
>>> TOday".)
>>>
>>> Possible? Stupid?
>>>
>> it's not stupid.
>>  People have used foot pedals for decades for a variety of controls. I  
>> don't
>> think foot pedals would work for me because when I am dictating, I pace.
>> Standing, sitting, I pace. With a cord headset, I'm forced to stay  
>> within about
>> 4 feet of the computer. But what I'm using a Bluetooth headset, I will  
>> sometimes
>> ramble as far as 10 or 15 feet from the computer. It helps if I make  
>> the font
>> larger so I can glance over and see what kind of errors I've gotten.
>>  I really love a Bluetooth headset with speech recognition. It's so  
>> liberating.
>>  Your question about foot pedals makes me think of alternative. would  
>> it make
>> sense to have a handheld keyboard which would be used for  
>> command-and-control
>> functionality or as an adjunct to speech recognition use? It would have  
>> to be
>> designed in such a way that it doesn't aggravate a hand injury which  
>> may not be
>> possible. Anyway, just thinking out loud.
>>
> You can get giant piano keyboards that you step on, so how about a giant
> computer keyboard? "I wrote 5 miles of code before lunch!" :-)

You can get/make MIDI organ pedal-boards (a friend of mine has two).  From
there it's just one small step...
:-)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From python.list at tim.thechases.com  Sun Jul  5 17:56:07 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sun, 05 Jul 2009 16:56:07 -0500
Subject: pep 8 constants
In-Reply-To: <op.uwl6tbzla8ncjz@gnudebst>
References: <mailman.7174.1231915778.3487.python-list@python.org>	<49a50517$0$3567$426a74cc@news.free.fr>
	<4A477991.4050109@harvee.org>	<op.uv89h1xqa8ncjz@gnudebst>
	<4A484C07.9050800@harvee.org>	<4A48A495.7040504@tim.thechases.com>
	<4A48E307.50804@harvee.org>	<4A49E232.6090101@tim.thechases.com>	<mailman.2392.1246375713.8015.python-list@python.org>	<BN23m.2219$ze1.1708@news-server.bigpond.net.au>	<b78ad4bc0907030428r7b1fb311ya03f2b2065939c25@mail.gmail.com>	<4A4E135E.5090400@harvee.org>
	<4A4E1B2F.2000700@mrabarnett.plus.com> <op.uwl6tbzla8ncjz@gnudebst>
Message-ID: <4A512177.8070106@tim.thechases.com>

>> You can get giant piano keyboards that you step on, so how about a giant
>> computer keyboard? "I wrote 5 miles of code before lunch!" :-)
> 
> You can get/make MIDI organ pedal-boards (a friend of mine has two).  From
> there it's just one small step...

Is that a two-step?  a box-step?  Count it off...slow, slow, 
quick, quick.  I think I just coded up Conway's Game of Life...

-tkc





From rhodri at wildebst.demon.co.uk  Sun Jul  5 18:03:13 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 05 Jul 2009 23:03:13 +0100
Subject: PEP368 and pixeliterators
In-Reply-To: <025db110$0$20657$c3e8da3@news.astraweb.com>
References: <mailman.2475.1246523526.8015.python-list@python.org>
	<025db110$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <op.uwl7jngya8ncjz@gnudebst>

On Fri, 03 Jul 2009 09:21:09 +0100, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> wrote:

> On Thu, 02 Jul 2009 10:32:04 +0200, Joachim Str?mbergson wrote:
>
>> for pixel in rgb_image:
>>     # swap red and blue, and set green to 0 pixel.value = pixel.b, 0,
>>     pixel.r
>>
>>
>> The idea I'm having is that fundamentally the image is made up of a 2D
>> array of pixels, not rows of pixels.
>
> A 2D array implies rows (and columns) of pixels.

But not necessarily an internal representation in which those rows or
columns are contiguous.  An efficient internal storage format might
well include margins to make transform edge cases easier, or store
the pixel components in separate arrays, or both.  I'd imagine that
quite frequently, the iterator across all pixels will in fact just
be hiding from the programmer the fact that it's really iterating
by row and then by pixel.  At Python's level of abstraction, that's
just fine, but the assumption that an image is made up of a 2D
array of pixels is not safe.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From torriem at gmail.com  Sun Jul  5 18:27:40 2009
From: torriem at gmail.com (Michael Torrie)
Date: Sun, 05 Jul 2009 16:27:40 -0600
Subject: Wrapping comments
In-Reply-To: <gubl1l$nov$4@lust.ihug.co.nz>
References: <towb-EA7906.14423909052009@news.individual.de>	<K8ydnaPzmfVQEpjXnZ2dnUVZ_gqdnZ2d@pdx.net>	<towb-445608.21342209052009@news.individual.de>	<m2bpq2ngup.fsf@googlemail.com>	<towb-63CE3D.09322210052009@news.individual.de>	<mailman.5400.1242000728.11746.python-list@python.org>	<slrnh0fqu4.qcl.nick@irishsea.home.craig-wood.com>
	<gubl1l$nov$4@lust.ihug.co.nz>
Message-ID: <4A5128DC.5060305@gmail.com>

Lawrence D'Oliveiro wrote:
> I tried using Emacs via SSH from a Mac once. Made me run screaming for the 
> nearest Windows box 
> <http://groups.google.co.nz/group/comp.sys.mac.advocacy/msg/dfad8bff6942e749>.

Interesting rant, but the problem is with the key bindings they chose to
use in Terminal.app program. Fortunately in leopard most of the problems
are now fixed, or can be configured to work in a non-broken fashion.
The rest of us, in the meantime, all switched to iTerm which, although
had some performance issues, behaved like we all expected terminals to
behave.

As far as terminal hell goes, I regularly find that when ssh-ing to
remote boxes that backspace doesn't work.  Or does in bash (because it's
 smart enough to play games) but not in vim.  Somehow sometimes over ssh
the key bindings for backspace get lost of messed up.




From http  Sun Jul  5 18:51:09 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 15:51:09 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<025ff51b$0$20657$c3e8da3@news.astraweb.com>
	<7xfxdbk61a.fsf@ruckus.brouhaha.com>
	<02605e46$0$20657$c3e8da3@news.astraweb.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
	<0260bf8d$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <7x8wj2agma.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> > but I don't accept that "somethingness"
> > vs. "nothingness" is the same distinction as truth vs falsehood.
> 
> It's the distinction used by Python since the dawn of time. Python only 
> grew a bool type a few versions back.

That's true, part of the situation we have now is an artifact of that
history.

> I'm not talking about the constants True and False (nouns), but about 
> true and false values (adjectives).

But, it seems to me, the constants True and False are the only values
to which the adjectives "true" and "false" should be applicable to.

> 
> > The idea that the "if"
> > statement selects between "somethingness" and "nothingness" rather than
> > between True and False is a bogus re-imagining of the traditional
> > function of an "if" statement 
> 
> There's nothing bogus about it.
> 
> > and has been an endless source of bugs in Python code.
> I wonder why these "endless" bugs weren't important enough to be 
> mentioned in the rationale to PEP 285:

Because adding the bool type doesn't really fix those bugs.

> describing `if x` as the "correct form" and calling scrapping such a
> feature as "crippling the language".

Certainly, changing "if" would have broken an immense amount of code
and been a completely unworkable approach.  We are using a fairly 
mature language by now; it has a culture and history that carries
certain baggage, as one should expect.

> > Look how much confusion it causes here in the newsgroup all the time.
> The only confusion is that you're causing me. Would you care to link to 
> some?

This current discussion (about bools) came from such confusion just a
few posts up in this very thread:

    From: upwestdon <upwestdon at gmail.com>
    Date: Fri, 3 Jul 2009 23:03:39 -0700 (PDT)
    How about just:

    if not (self.higher and self.lower):
        return self.higher or self.lower

That test was designed to treat None as a boolean False, without
noticing that numeric 0 is also treated as False and could make the
test do the wrong thing.  This is an extremely common type of error.

> > could see some value to having a generic "is_empty" predicate
> We have that already. It's spelled __bool__ or __nonzero__

That's fine, but under the "explicit is better than implicit"
principle, it's preferable to call that predicate explicitly: 
"if bool(x): ..." rather than "if x:".  Also, after many years of
fixing bugs caused by the mushing together of None and False, it seems
to me that we'd have been better off if bool(None) raised an exception
rather than returning false.  None is supposed to denote a nonexistent
value, not a false or empty value.  The only valid way to check
whether something is None should have been "if x is None".  However,
it is of course way too late to do this differently.

> Iterators are a special case, because in general they can't tell if 
> they're exhausted until they try to yield a value.

Right, it would be nice if they supported a lookahead slot, though
that would complicate a lot of __iter__ methods.  There's been various
kludgy attempts to wrap them in ways that support this, though.


From http  Sun Jul  5 18:53:34 2009
From: http (Paul Rubin)
Date: 05 Jul 2009 15:53:34 -0700
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<0a175b39-f084-4814-92e0-80b6cfce6130@c36g2000yqn.googlegroups.com>
Message-ID: <7x4otqagi9.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> BTW, Paul, kind of a tangent: I reimplemented the same algorithm but
> using tuples instead of instances (and empty tuples for "NULL"
> values.)  I was trying to mess around in the space you seemed to
> indicate existed, i.e. a better implementation using other datatypes,
> but I didn't have a clear idea what I was doing and, as I said, I
> started by simply re-implementing with a different datatype.
> 
> Much to my surprise and delight, I discovered the tuple-based BTree
> was /already/ a "persistent data type"!  It was both awesome and a bit
> of an anti-climax. :]

Cool ;-).  It also seems to me a bit irregular to require every tree
to have a node with optional children, rather than allowing trees to be
compleely empty.  I think the irregularity complicated the code somewhat.


From ldo at geek-central.gen.new_zealand  Sun Jul  5 18:54:43 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 10:54:43 +1200
Subject: Wrapping comments
References: <towb-EA7906.14423909052009@news.individual.de>
	<K8ydnaPzmfVQEpjXnZ2dnUVZ_gqdnZ2d@pdx.net>
	<towb-445608.21342209052009@news.individual.de>
	<m2bpq2ngup.fsf@googlemail.com>
	<towb-63CE3D.09322210052009@news.individual.de>
	<mailman.5400.1242000728.11746.python-list@python.org>
	<slrnh0fqu4.qcl.nick@irishsea.home.craig-wood.com>
	<gubl1l$nov$4@lust.ihug.co.nz>
	<mailman.2656.1246832876.8015.python-list@python.org>
Message-ID: <h2ravj$qto$1@lust.ihug.co.nz>

In message <mailman.2656.1246832876.8015.python-list at python.org>, Michael 
Torrie wrote:

> Lawrence D'Oliveiro wrote:
>
>> I tried using Emacs via SSH from a Mac once. Made me run screaming for
>> the nearest Windows box
>> 
<http://groups.google.co.nz/group/comp.sys.mac.advocacy/msg/dfad8bff6942e749>.
> 
> Interesting rant, but the problem is with the key bindings they chose to
> use in Terminal.app program.

Except for control-space, which was defined systemwide to bring up 
Spotlight. So you can't blame the Terminal app for that. The brain damage 
was more widespread than just one program.



From contact at xavierho.com  Sun Jul  5 20:20:39 2009
From: contact at xavierho.com (Xavier Ho)
Date: Mon, 6 Jul 2009 10:20:39 +1000
Subject: Why is my code faster with append() in a loop than with a large list?
Message-ID: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>

(Here's a short version of the long version below if you don't want to
read:)

Why is version B of the code faster than version A? (Only three lines
different)

Version A: http://pastebin.com/f14561243
Version B: http://pastebin.com/f1f657afc

------------------------------------------------

I was doing the problems on Project Euler for practice with Python last
night. Problem 12 was to find the value of the first triangular number that
has over 500 divisors.
=========================================================================================

The sequence of triangle numbers is generated by adding the natural numbers.
So the 7[image: ^(]th[image: )] triangle number would be 1 + 2 + 3 + 4 + 5 +
6 + 7 = 28. The first ten terms would be:

1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...

Let us list the factors of the first seven triangle numbers:

* 1*: 1
* 3*: 1,3
* 6*: 1,2,3,6
*10*: 1,2,5,10
*15*: 1,3,5,15
*21*: 1,3,7,21
*28*: 1,2,4,7,14,28

We can see that 28 is the first triangle number to have over five divisors.

What is the value of the first triangle number to have over five hundred
divisors?
=========================================================================================

My initial code was to loop through from 1 to half the number and see which
were divisors, and as I find them I store them in a list. That would have
taken days.

My second try was factorising the number each time, and count the divisors
using the powers of each factor, plus 1, and multiply together.
The code is here (Version A): http://pastebin.com/f14561243

This worked, but it took overnight to compute. Before I went to bed a friend
of mine caught me online, and apparently left me a working version under 8
seconds with only 3 line difference.
The code is here (Version B): http://pastebin.com/f1f657afc

That was amazing. But I have no idea why his edit makes it so much faster. I
did a test to see whether if append() was faster (which I doubted) than
defining a list with a large size to begin with, and I was right:
http://pastebin.com/f4b46d0db
Which shows that appending is 40x slower, and was expected. But I still
can't puzzle out why his use of appending in Version B was so much faster
than mine.

Any insights would be welcome. I'm going on a family trip, though, so my
replies may delay.

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/853296e4/attachment-0001.html>

From fetchinson at googlemail.com  Sun Jul  5 20:23:49 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Sun, 5 Jul 2009 17:23:49 -0700
Subject: memoization module?
In-Reply-To: <h2r381$q5l$1@reader1.panix.com>
References: <h2r381$q5l$1@reader1.panix.com>
Message-ID: <fbe2e2100907051723i6e40c8e5y468e34112a8070e@mail.gmail.com>

> Is there a memoization module for Python?  I'm looking for something
> like Mark Jason Dominus' handy Memoize module for Perl.

The Python Cookbook has several examples:

http://www.google.com/search?q=python+memoize&sitesearch=code.activestate.com

HTH,
Daniel




-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From ldo at geek-central.gen.new_zealand  Sun Jul  5 20:30:30 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 12:30:30 +1200
Subject: PEP 376
References: <mailman.2410.1246390911.8015.python-list@python.org>
	<h2ec5l$820$1@lust.ihug.co.nz>
	<73587ae3-4f4f-4243-a8af-cf4a6bfb598b@k26g2000vbp.googlegroups.com>
	<mailman.2422.1246418400.8015.python-list@python.org>
	<h2f7jt$j33$1@south.jnrs.ja.net>
	<4A4C685A.8020300@Strombergson.com>
	<94bdd2610907020455x35239f45jc35290f5c21d3229@mail.gmail.com>
	<mailman.2489.1246540523.8015.python-list@python.org>
	<1f63m.2229$ze1.1410@news-server.bigpond.net.au>
	<mailman.2507.1246557664.8015.python-list@python.org>
Message-ID: <h2rgj7$th1$9@lust.ihug.co.nz>

In message <mailman.2507.1246557664.8015.python-list at python.org>, Charles 
Yeomans wrote:

> On the contrary, MD5 was intended to be a cryptographic hash function,
> not a checksum.

Just like MD4 and MD2 before it. They have long since been considered 
worthless, and now MD5 has joined them.



From Scott.Daniels at Acm.Org  Sun Jul  5 20:30:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Sun, 05 Jul 2009 17:30:58 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <4A4FDCAF.8010209@Acm.Org>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org>
Message-ID: <UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>

Scott David Daniels wrote:
> ... Here's a heuristic replacement for my previous frequency code:
> I've tried to mark where you could fudge numbers if the run time
> is at all close.

Boy, I cannot let go.  I did a bit of a test checking for cost to
calculated number of discovered samples, and found after:
     import timeit
     import numpy
     original = numpy.random.random(0, 100, (1000, 1000)).astype(int)
     data = original.flatten()
     data.sort()
     part = data[::100]
     t = timeit.Timer('sum(part[:-1]==part[1:])',
                      'from __main__ import part')
     v = timeit.Timer('len(part[part[:-1]==part[1:]])',
                      'from __main__ import part')

I got:
 >>> t.repeat(3, 10)
[0.58319842326318394, 0.57617574300638807, 0.57831819407238072]
 >>> v.repeat(3, 1000)
[0.93933027801040225, 0.93704535073584339, 0.94096260837613954]

So, len(part[mask]) is almost 50X faster!  I checked:
 >>> sum(part[:-1]==part[1:])
9393
 >>> len(part[part[:-1]==part[1:]])
9393

That's an awful lot of matches, so I with high selectivity:
     data = original.flatten()  # no sorting, so runs missing
     part = data[::100]

 >>> t.repeat(3, 10)
[0.58641335700485797, 0.58458854407490435, 0.58872594142576418]
 >>> v.repeat(3, 1000)
[0.27352554584422251, 0.27375686015921019, 0.27433291102624935]

about 200X faster

 >>> len(part[part[:-1]==part[1:]])
39
 >>> sum(part[:-1]==part[1:])
39

So my new version of this (compressed) code:
>     ...
>     sampled = data[::stride]
>     matches = sampled[:-1] == sampled[1:]
>     candidates = sum(matches) # count identified matches
>     while candidates > N * 10: # 10 -- heuristic
>         stride *= 2 # # heuristic increase
>         sampled = data[::stride]
>         matches = sampled[:-1] == sampled[1:]
>         candidates = sum(matches)
>     while candidates < N * 3: # heuristic slop for long runs
>         stride //= 2 # heuristic decrease
>         sampled = data[::stride]
>         matches = sampled[:-1] == sampled[1:]
>         candidates = sum(matches)
>     former = None
>     past = 0
>     for value in sampled[matches]:
>         ...
is:
       ...
       sampled = data[::stride]
       candidates = sampled[sampled[:-1] == sampled[1:]]
       while len(candidates) > N * 10: # 10 -- heuristic
           stride *= 2 # # heuristic increase
           sampled = data[::stride]
           candidates = sampled[sampled[:-1] == sampled[1:]]
       while len(candidates) < N * 3: # heuristic slop for long runs
           stride //= 2 # heuristic decrease
           sampled = data[::stride]
           candidates = sampled[sampled[:-1] == sampled[1:]]
       former = None
       past = 0
       for value in candidates:
           ...
This change is important, for we try several strides before
settling on a choice, meaning the optimization can be valuable.
This also means we could be pickier at choosing strides (try
more values), since checking is cheaper than before.

Summary: when dealing with numpy, (or any bulk <-> individual values
transitions), try several ways that you think are equivalent and
_measure_.  In the OODB work I did we called this "impedance mismatch,"
and it is likely some boundary transitions are _much_ faster than
others.  The sum case is one of them; I am getting numpy booleans
back, rather than numpy booleans, so conversions aren't going fastpath.

--Scott David Daniels
Scott.Daniels at Acm.Org


From timr at probo.com  Sun Jul  5 20:36:11 2009
From: timr at probo.com (Tim Roberts)
Date: Sun, 05 Jul 2009 17:36:11 -0700
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
Message-ID: <lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>

"jack catcher (nick)" <nomail at thank.you> wrote:
>
>I'm thinking of using Python for capturing and showing live webcam 
>stream simultaneously between two computers via local area network. 
>Operating system is Windows. I'm going to begin with VideoCapture 
>extension, no ideas about other implementation yet. Do you have any 
>suggestions on how short delay I should hope to achieve in showing the 
>video? This would be part of a psychological experiment, so I would need 
>to deliver the video stream with a reasonable delay (say, below 100ms).

You need to do the math on this.  Remember that a full 640x480 RGB stream
at 30 frames per second runs 28 megabytes per second.  That's more than
twice what a 100 megabit network can pump.

You can probably use Python to oversee this, but you might want to consider
using lower-level code to control the actual hardware.  If you are
targeting Windows, for example, you could write a DirectShow graph to pump
into a renderer that transmits out to a network, then another graph to
receive from the network and display it.

You can manage the network latency by adding a delays in the local graph.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From david at pythontoo.com  Sun Jul  5 20:48:39 2009
From: david at pythontoo.com (David)
Date: Sun, 05 Jul 2009 20:48:39 -0400
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <4A5149E7.6030809@pythontoo.com>

Xavier Ho wrote:
> (Here's a short version of the long version below if you don't want to 
> read:)
> 
> Why is version B of the code faster than version A? (Only three lines 
> different)
> 
> Version A: http://pastebin.com/f14561243
> Version B: http://pastebin.com/f1f657afc
I don't know but here is the diff for someone that may;

1c1,2
< # This one only took 8 seconds on my machine. Wow?
---
 >
 > # This one took hours to compute, overnight.
28c29
<     powers = [0, 0]
---
 >     powers = [0] * (num + 1)
32c33
<             powers[factor-1] += 1
---
 >             powers[factor] += 1
35d35
<             powers.append(0)
55c55
<     n += 1
\ No newline at end of file
---
 >     n += 1


-- 
Powered by Gentoo GNU/Linux
http://linuxcrazy.com


From python at mrabarnett.plus.com  Sun Jul  5 20:54:39 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 01:54:39 +0100
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <4A514B4F.6010408@mrabarnett.plus.com>

Xavier Ho wrote:
> (Here's a short version of the long version below if you don't want to 
> read:)
> 
> Why is version B of the code faster than version A? (Only three lines 
> different)
> 
> Version A: http://pastebin.com/f14561243
> Version B: http://pastebin.com/f1f657afc
> 
> ------------------------------------------------
> 
> I was doing the problems on Project Euler for practice with Python last 
> night. Problem 12 was to find the value of the first triangular number 
> that has over 500 divisors.
> =========================================================================================
> 
> The sequence of triangle numbers is generated by adding the natural 
> numbers. So the 7^(^th ) triangle number would be 1 + 2 + 3 + 4 + 5 + 6 
> + 7 = 28. The first ten terms would be:
> 
> 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
> 
> Let us list the factors of the first seven triangle numbers:
> 
>     * 1*: 1
>     * 3*: 1,3
>     * 6*: 1,2,3,6
>     *10*: 1,2,5,10
>     *15*: 1,3,5,15
>     *21*: 1,3,7,21
>     *28*: 1,2,4,7,14,28
> 
> We can see that 28 is the first triangle number to have over five divisors.
> 
> What is the value of the first triangle number to have over five hundred 
> divisors?
> 
> =========================================================================================
> 
> My initial code was to loop through from 1 to half the number and see 
> which were divisors, and as I find them I store them in a list. That 
> would have taken days.
> 
> My second try was factorising the number each time, and count the 
> divisors using the powers of each factor, plus 1, and multiply together.
> The code is here (Version A): http://pastebin.com/f14561243
> 
> This worked, but it took overnight to compute. Before I went to bed a 
> friend of mine caught me online, and apparently left me a working 
> version under 8 seconds with only 3 line difference.
> The code is here (Version B): http://pastebin.com/f1f657afc
> 
> That was amazing. But I have no idea why his edit makes it so much 
> faster. I did a test to see whether if append() was faster (which I 
> doubted) than defining a list with a large size to begin with, and I was 
> right:
> http://pastebin.com/f4b46d0db
> Which shows that appending is 40x slower, and was expected. But I still 
> can't puzzle out why his use of appending in Version B was so much 
> faster than mine.
> 
> Any insights would be welcome. I'm going on a family trip, though, so my 
> replies may delay.
> 
In your version you're creating a list of (num + 1) elements, but in the
other version the list is only as long as the largest factor.

For example, for num=28, your version creates a list 29 elements long,
but the other version creates one only 7 elements long. Also, 'the time
needed to append an item to the list is "amortized constant"' (quoted
from http://effbot.org/zone/python-list.htm).

This means that your little speed test isn't representation of what's
actually happening.


From notvalid2 at sbcglobal.net  Sun Jul  5 21:48:46 2009
From: notvalid2 at sbcglobal.net (W. eWatson)
Date: Sun, 05 Jul 2009 18:48:46 -0700
Subject: Adding the Copy Property to a Simple Histogram
Message-ID: <WJc4m.2086$8r.1195@nlpi064.nbdc.sbc.com>

The code below produces a text window 60hx20w with a scroll bar. The 
contents are something of a histogram of values from 0 to 255. If one tries 
to copy the contents, Windows doesn't allow it. What needs to be done to 
allow a copy and paste?

     def ShowHistogram(self):
         if not self.current_image:
             return

         if self.histogram:
             self.histogram.destroy()

         t = Toplevel( self.master )
         t.title("Histogram")
         t.bind( '<Destroy>', self.DestroyHistogram )
         text = Text( t, height=60, width=20 )
         scroll = Scrollbar(t, command=text.yview)
         text.configure(yscrollcommand=scroll.set)
         text.pack(side=LEFT, fill='both', expand=1)
         scroll.pack(side=RIGHT, fill=Y)
         self.histogram = t

         hist = self.current_image.histogram()
         for i in range(len(hist)):
             msg = "%5d %6d\n" % (i,hist[i])
             text.insert( END, msg )
-- 
                                W. eWatson

              (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
               Obz Site:  39? 15' 7" N, 121? 2' 32" W, 2700 feet

                     Web Page: <www.speckledwithstars.net/>



From tanner989 at hotmail.com  Sun Jul  5 22:06:30 2009
From: tanner989 at hotmail.com (tanner barnes)
Date: Sun, 5 Jul 2009 21:06:30 -0500
Subject: Help with Sockets.
Message-ID: <BAY122-W4920057777399CD2F5C824F52B0@phx.gbl>


I am writing a program and in one section there is going to be a lobby with (for testing purposes) about 4 people in it. in the lobby there are two txtctrl's the first for entering your message and the second for displaying the message you and the other people in the lobby type. i am trying to figure out how to get all the text entrys from the users and display them in the second one. For clarification and example of what i want would be like yahoo or windows live messanger but for more than 2 people. 

Python version: 2.6
GUI toolkit: WxPython


_________________________________________________________________
Hotmail? has ever-growing storage! Don?t worry about storage limits. 
http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090705/9296433d/attachment-0001.html>

From maymunbeyin at gmail.com  Sun Jul  5 22:27:25 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 19:27:25 -0700 (PDT)
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
Message-ID: <22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>

Hi

Thank you so much for wonderful tips and suggestions.

I also found a solution to dynamic naming of the instances(I think).
It does not sound like a very secure method but since my application
will be just processing data one way I think it might be alright. I
will compare to the list and dictionary methods.

globals()["Some_Instance_Name"]



From ldo at geek-central.gen.new_zealand  Sun Jul  5 22:32:46 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 14:32:46 +1200
Subject: A Bug By Any Other Name ...
Message-ID: <h2rnoe$26s$5@lust.ihug.co.nz>

I wonder how many people have been tripped up by the fact that

    ++n

and

    --n

fail silently for numeric-valued n.



From clp2 at rebertia.com  Sun Jul  5 22:45:39 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 5 Jul 2009 19:45:39 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2rnoe$26s$5@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <50697b2c0907051945x67f97094s370449fa6d05b449@mail.gmail.com>

On Sun, Jul 5, 2009 at 7:32 PM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> I wonder how many people have been tripped up by the fact that
>
> ? ?++n
>
> and
>
> ? ?--n
>
> fail silently for numeric-valued n.

Given that C-style for-loops are relatively infrequent in Python and
are usually written using range() when they are needed, it's probably
not that prevalent a problem.
I suppose the lexer could be changed to make ++ and -- illegal...

Cheers,
Chris
-- 
http://blog.rebertia.com


From sajmikins at gmail.com  Sun Jul  5 23:11:51 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sun, 5 Jul 2009 20:11:51 -0700 (PDT)
Subject: Adding the Copy Property to a Simple Histogram
References: <WJc4m.2086$8r.1195@nlpi064.nbdc.sbc.com>
Message-ID: <a545e526-a6fe-4411-9603-a85722f526fa@d32g2000yqh.googlegroups.com>

On Jul 5, 9:48?pm, "W. eWatson" <notval... at sbcglobal.net> wrote:
> The code below produces a text window 60hx20w with a scroll bar. The
> contents are something of a histogram of values from 0 to 255. If one tries
> to copy the contents, Windows doesn't allow it. What needs to be done to
> allow a copy and paste?
>
> ? ? ?def ShowHistogram(self):
> ? ? ? ? ?if not self.current_image:
> ? ? ? ? ? ? ?return
>
> ? ? ? ? ?if self.histogram:
> ? ? ? ? ? ? ?self.histogram.destroy()
>
> ? ? ? ? ?t = Toplevel( self.master )
> ? ? ? ? ?t.title("Histogram")
> ? ? ? ? ?t.bind( '<Destroy>', self.DestroyHistogram )
> ? ? ? ? ?text = Text( t, height=60, width=20 )
> ? ? ? ? ?scroll = Scrollbar(t, command=text.yview)
> ? ? ? ? ?text.configure(yscrollcommand=scroll.set)
> ? ? ? ? ?text.pack(side=LEFT, fill='both', expand=1)
> ? ? ? ? ?scroll.pack(side=RIGHT, fill=Y)
> ? ? ? ? ?self.histogram = t
>
> ? ? ? ? ?hist = self.current_image.histogram()
> ? ? ? ? ?for i in range(len(hist)):
> ? ? ? ? ? ? ?msg = "%5d %6d\n" % (i,hist[i])
> ? ? ? ? ? ? ?text.insert( END, msg )
> --
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? W. eWatson
>
> ? ? ? ? ? ? ? (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
> ? ? ? ? ? ? ? ?Obz Site: ?39? 15' 7" N, 121? 2' 32" W, 2700 feet
>
> ? ? ? ? ? ? ? ? ? ? ?Web Page: <www.speckledwithstars.net/>

Do you mean that the Text widget doesn't let you copy-and-paste copy
its contents using selection and <Control-c>?  That shouldn't have
anything to do with the contents of the Text widget.


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 23:28:43 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 03:28:43 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <006d4a50$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:

> I wonder how many people have been tripped up by the fact that
> 
>     ++n
> 
> and
> 
>     --n
> 
> fail silently for numeric-valued n.

What do you mean, "fail silently"? They do exactly what you should expect:


>>> ++5  # positive of a positive number is positive
5
>>> --5  # negative of a negative number is positive
5
>>> -+5  # negative of a positive number is negative
-5

So does the bitwise-not unary operator:

>>> ~~5
5


I'm not sure what "bug" you're seeing. Perhaps it's your expectations 
that are buggy, not Python.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 23:28:55 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 03:28:55 GMT
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org> <UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>
Message-ID: <006d4a5c$0$9711$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 17:30:58 -0700, Scott David Daniels wrote:

> Summary: when dealing with numpy, (or any bulk <-> individual values
> transitions), try several ways that you think are equivalent and
> _measure_.

This advice is *much* more general than numpy -- it applies to any 
optimization exercise. People's intuitions about what's fast and what's 
slow are often very wrong.


-- 
Steven


From notvalid2 at sbcglobal.net  Sun Jul  5 23:33:48 2009
From: notvalid2 at sbcglobal.net (W. eWatson)
Date: Sun, 05 Jul 2009 20:33:48 -0700
Subject: Adding the Copy Property to a Simple Histogram
In-Reply-To: <a545e526-a6fe-4411-9603-a85722f526fa@d32g2000yqh.googlegroups.com>
References: <WJc4m.2086$8r.1195@nlpi064.nbdc.sbc.com>
	<a545e526-a6fe-4411-9603-a85722f526fa@d32g2000yqh.googlegroups.com>
Message-ID: <rge4m.2366$Wj7.1684@nlpi065.nbdc.sbc.com>

Simon Forman wrote:
> On Jul 5, 9:48 pm, "W. eWatson" <notval... at sbcglobal.net> wrote:
>> The code below produces a text window 60hx20w with a scroll bar. The
>> contents are something of a histogram of values from 0 to 255. If one tries
>> to copy the contents, Windows doesn't allow it. What needs to be done to
>> allow a copy and paste?
>>
>>      def ShowHistogram(self):
>>          if not self.current_image:
>>              return
>>
>>          if self.histogram:
>>              self.histogram.destroy()
>>
>>          t = Toplevel( self.master )
>>          t.title("Histogram")
>>          t.bind( '<Destroy>', self.DestroyHistogram )
>>          text = Text( t, height=60, width=20 )
>>          scroll = Scrollbar(t, command=text.yview)
>>          text.configure(yscrollcommand=scroll.set)
>>          text.pack(side=LEFT, fill='both', expand=1)
>>          scroll.pack(side=RIGHT, fill=Y)
>>          self.histogram = t
>>
>>          hist = self.current_image.histogram()
>>          for i in range(len(hist)):
>>              msg = "%5d %6d\n" % (i,hist[i])
>>              text.insert( END, msg )
>> --
>>                                 W. eWatson
>>
>>               (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
>>                Obz Site:  39? 15' 7" N, 121? 2' 32" W, 2700 feet
>>
>>                      Web Page: <www.speckledwithstars.net/>
> 
> Do you mean that the Text widget doesn't let you copy-and-paste copy
> its contents using selection and <Control-c>?  That shouldn't have
> anything to do with the contents of the Text widget.
Whoops, I missed it. I'm not quite sure what I did to make it seem like it 
doesn't copy, but it does. I fooled myself. All is well.

-- 
                                W. eWatson

              (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
               Obz Site:  39? 15' 7" N, 121? 2' 32" W, 2700 feet

                     Web Page: <www.speckledwithstars.net/>



From steve at REMOVE-THIS-cybersource.com.au  Sun Jul  5 23:46:41 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 03:46:41 GMT
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
Message-ID: <006d4e86$0$9711$c3e8da3@news.astraweb.com>

On Sun, 05 Jul 2009 19:27:25 -0700, kk wrote:

> Hi
> 
> Thank you so much for wonderful tips and suggestions.
> 
> I also found a solution to dynamic naming of the instances(I think). It
> does not sound like a very secure method but since my application will
> be just processing data one way I think it might be alright. I will
> compare to the list and dictionary methods.
> 
> globals()["Some_Instance_Name"]


You're fighting the computer instead of working with it. That's the Wrong 
Way to solve the problem -- you're doing more work than needed, for 
little or no benefit.

My bet is, you have code that looks something like this:


for i in range(N):  # N comes from somewhere else
    # Create a new variable
    globals()["Some_Instance_Name%s" % i] = instance()

# Do something with the variables
for i in range(N):
    # Look up the variable
    x = globals()["Some_Instance_Name%s" % i]
    process(x)


Am I close?

That's the Wrong Way to do it -- you're using a screwdriver to hammer a 
nail. The right way to work with an unknown number of data elements is to 
put them in a list, and process each element in the list, not to try 
giving them all unique names. The only reason for using named variables 
is so you can use the name in source code:

my_value = Some_Instance87 + Some_Instance126

But you can't do that, because you don't know how many instances there 
are, you don't know whether to write Some_Instance87 or Some_Instance125 
or Some_Instance19.


So instead, do something like this:


instances = []
for i in range(N):
    # Create a new instance and store it for later
    instances.append( instance() )

# Later on:
for x in instances():
    process(x)




-- 
Steven


From dns4 at cornell.edu  Sun Jul  5 23:53:56 2009
From: dns4 at cornell.edu (David Smith)
Date: Sun, 05 Jul 2009 23:53:56 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2oggj$n9p$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
	<7x4otsux7f.fsf@ruckus.brouhaha.com>
	<h2oggj$n9p$1@reader1.panix.com>
Message-ID: <h2rsgi$7s2$1@ruby.cit.cornell.edu>

kj wrote:
> In <7x4otsux7f.fsf at ruckus.brouhaha.com> Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:
> 
>> kj <no.email at please.post> writes:
>>>     sense = cmp(func(hi), func(lo))
>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
> 
>> bisection search usually just requires the function to be continuous
>> and to have its value cross the target somewhere between the endpoints,
>> not be monotonic.
> 
> Try the algorithm I posted with lo = -pi/4, hi = 2*pi, func = cos,
> target = -1, and see what you get...
> 
>>> I regard the very special case of func(hi)==func(lo)==target as
>>> pathological (analogous to the fact that a stopped watch is "exactly
>>> right" twice a day), and not one I care to support.
> 
>> I do think you should support that case, under the "do 'nothing'
>> gracefully" principle.
> 
> You keep missing the point that this is an *internal* *helper*
> *convenience* function, meant to abstract away common logic from
> a handful of places and thus eliminate some code repetition within
> a module.  It is *not* a library function intended to be called
> from elsewhere.  So talk of "supporting" anything is besides the
> point.  Any internal use of this function that applies it to a
> non-strictly-monotonic function is, by assumption, an error.
> 
> kj

First, let me say *I got the point*.  I use asserts, but only in unit
testing where I want to test the result of some action for correctness.
 In the course of programming product code, I personally don't think
they should ever be used exactly for the reasons everyone else is
pointing out.  They can be disabled with the -O option and that changes
the program's behavior in ways that could break in production.

If you insist on teaching the assert statement, teach it in the context
of writing unit testing code.  Its an extremely valuable skill.

--David


From casevh at gmail.com  Mon Jul  6 01:04:36 2009
From: casevh at gmail.com (casevh)
Date: Sun, 5 Jul 2009 22:04:36 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
Message-ID: <mailman.2695.1246892380.8015.python-announce-list@python.org>

An alpha release of GMPY that supports Python 2 and 3 is available.
GMPY is a wrapper for the GMP multiple-precision arithmetic
library. The MPIR multiple-precision arithmetic library is also
supported. GMPY is available for download from
http://code.google.com/p/gmpy/

Support for Python 3 required many changes to the logic used to
convert between different numerical types. The result type of some
combinations has changed. For example, 'mpz' + 'float' now returns
an 'mpf' instead of a 'float'. See the file "changes.txt" for more
information.

In addition to support for Python 3, there are several other
changes and bug fixes:

- Bug fixes in mpz.binary() and mpq.binary().

- Unicode strings are accepted as input on Python 2.
  (Known bug: works for mpz, fails for mpq and mpf)

- The overhead for calling GMPY routines has been reduced.
  If one operand in a small integer, it is not converted to mpz.

- 'mpf' and 'mpq' now support % and divmod.

Comments on provided binaries

The 32-bit Windows installers were compiled using MPIR 1.2.1 and
will automatically recognize the CPU type and use code optimized for
that CPU.

Please test with your applications and report any issues found!

casevh


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 01:19:51 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 02:19:51 -0300
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> escribi?:
> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>
>> I wonder how many people have been tripped up by the fact that
>>
>>     ++n
>>
>> and
>>
>>     --n
>>
>> fail silently for numeric-valued n.
>
> What do you mean, "fail silently"? They do exactly what you should  
> expect:
>>>> ++5  # positive of a positive number is positive
>
> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
> that are buggy, not Python.

Well, those expectations are taken seriously when new features are  
introduced into the language - and sometimes the feature is dismissed just  
because it would be confusing for some.
If a += 1 works, expecting ++a to have the same meaning is very reasonable  
(for those coming from languages with a ++ operator, like C or Java) -  
more when ++a is a perfectly valid expression.
If this issue isn't listed under the various "Python gotchas" articles, it  
should...

-- 
Gabriel Genellina



From banibrata.dutta at gmail.com  Mon Jul  6 01:37:19 2009
From: banibrata.dutta at gmail.com (Banibrata Dutta)
Date: Mon, 6 Jul 2009 11:07:19 +0530
Subject: mail
In-Reply-To: <22154.210.212.36.65.1246724472.squirrel@www.iisermohali.ac.in>
References: <22154.210.212.36.65.1246724472.squirrel@www.iisermohali.ac.in>
Message-ID: <3de8e1f70907052237m442e563bj4e040eec12d63f0d@mail.gmail.com>

On Sat, Jul 4, 2009 at 9:51 PM, <amrita at iisermohali.ac.in> wrote:

> Hi,
>
> I want to know that whether using python programming is it possible to
> extract chemical shift information about some amino acids of some protein
> from BMRB(BioMagResBank) or Ref-DB(referenced databank) or not.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
>

Without any real knowledge of the problem domain, but with keyword level
google search, here's one one finds --
http://www.ccpn.ac.uk/api-documentation/ccpnmr/ccpnmr2.0/python/doc/api.html
<http://www.ccpn.ac.uk/api-documentation/ccpnmr/ccpnmr2.0/python/doc/api.html>
http://biopython.org/wiki/Main_Page
<http://biopython.org/wiki/Main_Page>http://chempython.org/
<http://chempython.org/>http://www.sschwarzer.net/

Also as Grant says, if you can create a software program in any language,
you can potentially do it with Python as well. As Python is a "batteries
included" language, chances are, the included-batteries would make your life
easier. Of course mileage may vary. If you find existing modules that do
much of what you want, you have a very good starting point.
-- 
regards,
Banibrata
http://www.linkedin.com/in/bdutta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/8d72613c/attachment-0001.html>

From maymunbeyin at gmail.com  Mon Jul  6 01:50:36 2009
From: maymunbeyin at gmail.com (kk)
Date: Sun, 5 Jul 2009 22:50:36 -0700 (PDT)
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <b5040c01-ce88-4edb-8b9a-7bb3b58d4e2a@g19g2000yql.googlegroups.com>

Steven,

Before your post I was contemplating about the merits of using the
globals(). After reading your post I am totally convinced that your
suggestion that was also suggested by previous posters is the way to
go. At first I thought it would be limiting to not to have the
instance names properly setup, but now I understand it better.

thank you all again.


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 01:58:59 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 02:58:59 -0300
Subject: Does cProfile include IO wait time?
References: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>
Message-ID: <op.uwmtkllgx6zn5v@lepton.softlabbsas.com.ar>

En Sat, 04 Jul 2009 21:03:38 -0300, Matthew Wilson <matt at tplus1.com>  
escribi?:

> I expected to see a bunch of my IO file-reading code in there, but I  
> don't.  So
> this makes me think that the profiler uses CPU time, not
> clock-on-the-wall time.
> I'm not an expert on python profiling, and the docs seem sparse.  Can I
> rule out IO as the bottleneck here?  How do I see the IO consequences?

I don't know either - but it's easy to check.
Write a program that just reads a lot from /dev/zero, and look at its  
profile. You should be able to tell whether I/O time is included or not.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 02:10:25 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 03:10:25 -0300
Subject: Help with Sockets.
References: <BAY122-W4920057777399CD2F5C824F52B0@phx.gbl>
Message-ID: <op.uwmt3nbmx6zn5v@lepton.softlabbsas.com.ar>

En Sun, 05 Jul 2009 23:06:30 -0300, tanner barnes <tanner989 at hotmail.com>  
escribi?:

> I am writing a program and in one section there is going to be a lobby  
> with (for testing purposes) about 4 people in it. in the lobby there are  
> two txtctrl's the first for entering your message and the second for  
> displaying the message you and the other people in the lobby type. i am  
> trying to figure out how to get all the text entrys from the users and  
> display them in the second one. For clarification and example of what i  
> want would be like yahoo or windows live messanger but for more than 2  
> people.

Like a chat room, IRC?
It's easy to do using a client-server architecture.
Make all the clients connect to a central server. Any time someone writes  
some text, the client sends it to the server (but does not display it).  
The server just receives text from any client, and sends the received  
messages to all connected clients (including the one that sent it  
originally).
Any book on socket programming will help; there are a few specific for  
Python.
You may start with the "echo" example in the Python documentation. Make  
the networking part work first, then add the wx GUI if you want.

-- 
Gabriel Genellina



From nomail at thank.you  Mon Jul  6 02:10:38 2009
From: nomail at thank.you (jack catcher (nick))
Date: Mon, 06 Jul 2009 09:10:38 +0300
Subject: Python and webcam capture delay?
In-Reply-To: <lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
Message-ID: <czg4m.20786$vi5.9666@uutiset.elisa.fi>

Tim Roberts kirjoitti:
> "jack catcher (nick)" <nomail at thank.you> wrote:
>> I'm thinking of using Python for capturing and showing live webcam 
>> stream simultaneously between two computers via local area network. 
>> Operating system is Windows. I'm going to begin with VideoCapture 
>> extension, no ideas about other implementation yet. Do you have any 
>> suggestions on how short delay I should hope to achieve in showing the 
>> video? This would be part of a psychological experiment, so I would need 
>> to deliver the video stream with a reasonable delay (say, below 100ms).
> 
> You need to do the math on this.  Remember that a full 640x480 RGB stream
> at 30 frames per second runs 28 megabytes per second.  That's more than
> twice what a 100 megabit network can pump.
> 
> You can probably use Python to oversee this, but you might want to consider
> using lower-level code to control the actual hardware.  If you are
> targeting Windows, for example, you could write a DirectShow graph to pump
> into a renderer that transmits out to a network, then another graph to
> receive from the network and display it.
> 
> You can manage the network latency by adding a delays in the local graph.

Thanks Tim, you're correct about the math. What is your main point about 
DirectShow: that it is generally faster and more reliable than doing the 
job high-level, or that one could use coding/decoding in DirectShow to 
speed up the transmission? I think the latter would be a great idea if 
the latency were tolerable. On the other hand, I'd like to keep things 
simple and do all the programming in Python. I've got no experience with 
DirectShow, but I guess the filters need to be programmed in C++ and 
called from Python?

Another option might be to use resolution 320x240 at 15fps.


From gherron at islandtraining.com  Mon Jul  6 02:33:36 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Sun, 05 Jul 2009 23:33:36 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A519AC0.1050905@islandtraining.com>

Gabriel Genellina wrote:
> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano 
> <steve at remove-this-cybersource.com.au> escribi?:
>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>
>>> I wonder how many people have been tripped up by the fact that
>>>
>>>     ++n
>>>
>>> and
>>>
>>>     --n
>>>
>>> fail silently for numeric-valued n.
>>
>> What do you mean, "fail silently"? They do exactly what you should 
>> expect:
>>>>> ++5  # positive of a positive number is positive
>>
>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>> that are buggy, not Python.
>
> Well, those expectations are taken seriously when new features are 
> introduced into the language - and sometimes the feature is dismissed 
> just because it would be confusing for some.
> If a += 1 works, expecting ++a to have the same meaning is very 
> reasonable (for those coming from languages with a ++ operator, like C 
> or Java) - more when ++a is a perfectly valid expression.
> If this issue isn't listed under the various "Python gotchas" 
> articles, it should...

Well sure, it's not unreasonable to expect ++n and --n to behave as in 
other languages, and since they don't, perhaps they should be listed as 
a "Python gotcha". 

But even so, it's quite arrogant of the OP to flaunt his ignorance of 
the language by claiming this is a bug and a failure.  It shouldn't have 
been all that hard for him to figure out what was really happening.

Gary Herron



From __peter__ at web.de  Mon Jul  6 02:33:53 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 06 Jul 2009 08:33:53 +0200
Subject: finding most common elements between thousands of multiple arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org>
	<UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>
Message-ID: <h2s5rm$m95$01$1@news.t-online.com>

Scott David Daniels wrote:

> Scott David Daniels wrote:

>      t = timeit.Timer('sum(part[:-1]==part[1:])',
>                       'from __main__ import part')

What happens if you calculate the sum in numpy? Try

t = timeit.Timer('(part[:-1]==part[1:]).sum()',
                 'from __main__ import part')


Peter



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 02:46:33 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 03:46:33 -0300
Subject: Method to separate unit-test methods and data?
References: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
	<be8f57070907051148x52ee305ch905c79bb0d59d983@mail.gmail.com>
Message-ID: <op.uwmvrvesx6zn5v@lepton.softlabbsas.com.ar>

En Sun, 05 Jul 2009 15:48:06 -0300, Nick Daly <nick.m.daly at gmail.com>  
escribi?:

> [test_Midpoint_mid]
> none_values = ((-1, None),
> ? ? ? ? ? ? ? (None, -12.8))
>
> What I haven't yet figured out how to do though, is properly override
> the default class member values with values from the config file. ?The
> config file's data is loaded as a string instead of as a list, as I'd
> want. ?This causes all the tests to fail, as while none_values needs
> to be interpreted as a list, it is instead understood as:
>
> " ((-1, None),\n ? ? ? ? ? ? ? (None, -12.8))"
>
> Does anyone have any solutions for these problems? ?

You may use a .py file to configure it, instead of your .cfg

> First, is there a
> known and simple way to separate unit-test data and methods into
> separate files? ?

Just write them in separate files? I didn't quite understand the  
question...

> Secondly, if not, is there a simple way to convert
> strings into other base types, like lists, dictionaries, and so forth?

eval(), but I'd just use a .py file
People usually warns against using eval on arbitrary strings, or on  
user-supplied data, but in this case it is not worse than  
importing/executing the module.

> Or, am I going to have to write my own list-parsing methods? ?Would
> pickling help? ?I haven't yet had a chance to look into if or how that
> would work... ?If there's anything else I can clarify about this
> request, feel free to let me know.

Another alternative would be a .csv file; I use them when the test data  
comes from other parties, like a manufacturer's data sheet.

I've never used a pickle to store test data - how do you generate the  
pickle contents in the first place? Usually I'd just use *that* code  
directly, but I think pickling the resulting objects would be OK is the  
process to regenerate them takes a lot of time.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 02:53:57 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 03:53:57 -0300
Subject: multiprocessing and freezing on Windows
References: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>
	<a205db1d-a801-4774-bfa1-124a723ea71b@p36g2000prn.googlegroups.com>
Message-ID: <op.uwmv37hsx6zn5v@lepton.softlabbsas.com.ar>

En Sat, 04 Jul 2009 22:15:43 -0300, SK <sgm at objexx.com> escribi?:

> To add a bit more information, I found that I needed to patch
> get_command_line in multiprocessing/forking.py [...]
>
> Is packaging with multiprocessing supposed to be this hard? If so,
> some documentation is needed.

Shouldn't be so hard, I presume. You may want to post your comments and  
upload the patch to http://bugs.python.org

-- 
Gabriel Genellina



From martin at librador.com  Mon Jul  6 03:44:33 2009
From: martin at librador.com (Martin Vilcans)
Date: Mon, 6 Jul 2009 09:44:33 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2l36k$q5l$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>

On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse. ?I'd love your opinion about
> it.

In general, code clarity is more important than reusability.
Unfortunately, many novice programmers have the opposite impression. I
have seen too much convoluted code written by beginners who try to
make the code generic. Writing simple, clear, to-the-point code is
hard enough as it is, even when not aiming at making it reusable.

If in the future you see an opportunity to reuse the code, then and
only then is the time to make it generic.

YAGNI is a wonderful principle.

-- 
martin at librador.com
http://www.librador.com


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 03:49:28 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 04:49:28 -0300
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
Message-ID: <op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 03:33:36 -0300, Gary Herron  
<gherron at islandtraining.com> escribi?:
> Gabriel Genellina wrote:
>> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano  
>> <steve at remove-this-cybersource.com.au> escribi?:
>>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>>
>>>> I wonder how many people have been tripped up by the fact that
>>>>
>>>>     ++n
>>>>
>>>> and
>>>>
>>>>     --n
>>>>
>>>> fail silently for numeric-valued n.
>>>
>>> What do you mean, "fail silently"? They do exactly what you should  
>>> expect:
>>>>>> ++5  # positive of a positive number is positive
>>>
>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>> that are buggy, not Python.
>>
>> Well, those expectations are taken seriously when new features are  
>> introduced into the language - and sometimes the feature is dismissed  
>> just because it would be confusing for some.
>> If a += 1 works, expecting ++a to have the same meaning is very  
>> reasonable (for those coming from languages with a ++ operator, like C  
>> or Java) - more when ++a is a perfectly valid expression.
>> If this issue isn't listed under the various "Python gotchas" articles,  
>> it should...
>
> Well sure, it's not unreasonable to expect ++n and --n to behave as in  
> other languages, and since they don't, perhaps they should be listed as  
> a "Python gotcha". But even so, it's quite arrogant of the OP to flaunt  
> his ignorance of the language by claiming this is a bug and a failure.   
> It shouldn't have been all that hard for him to figure out what was  
> really happening.

That depends on what you call a "bug". In his classical book "The art of  
software testing", Myers says that a program has a bug when it doesn't  
perform as the user expects reasonably it to do (not an exact quote, I  
don't have the book at hand). That's a lot broader than developers like to  
accept.

In this case, a note in the documentation warning about the potential  
confusion would be fine.

-- 
Gabriel Genellina



From andreengels at gmail.com  Mon Jul  6 03:51:04 2009
From: andreengels at gmail.com (Andre Engels)
Date: Mon, 6 Jul 2009 09:51:04 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
Message-ID: <6faf39c90907060051n65089c88od45c75c80f3a7ccf@mail.gmail.com>

On Mon, Jul 6, 2009 at 9:44 AM, Martin Vilcans<martin at librador.com> wrote:
> On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
>> I'm will be teaching a programming class to novices, and I've run
>> into a clear conflict between two of the principles I'd like to
>> teach: code clarity vs. code reuse. ?I'd love your opinion about
>> it.
>
> In general, code clarity is more important than reusability.
> Unfortunately, many novice programmers have the opposite impression. I
> have seen too much convoluted code written by beginners who try to
> make the code generic. Writing simple, clear, to-the-point code is
> hard enough as it is, even when not aiming at making it reusable.
>
> If in the future you see an opportunity to reuse the code, then and
> only then is the time to make it generic.

Not just that, when you actually get to that point, making simple and
clear code generic is often easier than making
complicated-and-supposedly-generic code that little bit more generic
that you need.


-- 
Andr? Engels, andreengels at gmail.com


From mail at timgolden.me.uk  Mon Jul  6 03:56:20 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 06 Jul 2009 08:56:20 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A51AE24.9080608@timgolden.me.uk>

Gabriel Genellina wrote:

[... re confusion over ++n etc ...]

> In this case, a note in the documentation warning about the potential 
> confusion would be fine.

The difficulty here is knowing where to put such a warning.
You obviously can't put it against the "++" operator as such
because... there isn't one. You could put it against the unary
plus operator, but who's going to look there? :)

I've wondered for a while whether it wouldn't be a good move
to include the official (or any other) Python FAQ into the
standard docs set. If we did, that would be the obvious place
for this piece of documentation, seems to me.

TJG


From stef.mientki at gmail.com  Mon Jul  6 04:05:32 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Mon, 06 Jul 2009 10:05:32 +0200
Subject: Python and webcam capture delay?
In-Reply-To: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
Message-ID: <4A51B04C.2080207@gmail.com>

jack catcher (nick) wrote:
> Hi,
>
> I'm thinking of using Python for capturing and showing live webcam 
> stream simultaneously between two computers via local area network. 
> Operating system is Windows. I'm going to begin with VideoCapture 
> extension, no ideas about other implementation yet. Do you have any 
> suggestions on how short delay I should hope to achieve in showing the 
> video? This would be part of a psychological experiment, so I would 
> need to deliver the video stream with a reasonable delay (say, below 
> 100ms).
I would first check if video capture extension works anyway.
I couldn't get it working, ...
... it seems to start ok
... but moving the captured window,
... or sometimes even just moving the mouse hangs the program :-(

So I'm still looking for a good / open source workiing video capture in 
Python.
I can make a good working capture in delphi,
make a DLL or ActiveX from that and use it in Python,
but I'm not allowed to ditribute these.

cheers,
Stef


From serverin2000 at yahoo.com  Mon Jul  6 04:11:27 2009
From: serverin2000 at yahoo.com (RAM)
Date: Mon, 6 Jul 2009 01:11:27 -0700 (PDT)
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
Message-ID: <d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>

On 5 July, 17:12, Tim Harig <user... at ilthio.net> wrote:
> On 2009-07-05, RAM <serverin2... at yahoo.com> wrote:
>
> > I need to start an external program and pass the keyboard events like
> > F1,Right arrow key etc to the program..I am trying to use the
> > subprocess module to invoke the external program. I am able to invoke
> > but not able to generate the keyboard events and pass them on to the
>
> catb.org/esr/faqs/smart-questions.html
>
> You have told us nothing about the environment where you are trying to
> accomplish this. ?GUI, CLI, Unix, Windows, etc? So I suggest that you
> checkout the curses getch functions. ?You can find them in the standard
> library documentation athttp://docs.python.org. ?You should also reference
> documentation for the C version in your systems man pages.

Hi Tim,

I am trying to do this on windows. My program(executable) has been
written in VC++ and when I run this program, I need to click on one
button on the program GUI i,e just I am entering "Enter key" on the
key board. But this needs manual process. So i need to write a python
script which invokes my program and pass "Enter key" event to my
program so that it runs without manual intervention.

Thank in advance for the help.

regards
Sreerama V


From david.m.cooke at gmail.com  Mon Jul  6 04:16:44 2009
From: david.m.cooke at gmail.com (David M. Cooke)
Date: Mon, 6 Jul 2009 08:16:44 +0000 (UTC)
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<4A50FDC6.1040604@v.loewis.de>
Message-ID: <loom.20090706T073723-420@post.gmane.org>

Martin v. L?wis <martin <at> v.loewis.de> writes:

> > This is a good test for Python implementation bottlenecks.  Run
> > that tokenizer on HTML, and see where the time goes.
> 
> I looked at it with cProfile, and the top function that comes up
> for a larger document (52k) is
> ...validator.HTMLConformanceChecker.__iter__.
[...]
> With this simple optimization, I get a 20% speedup on my test
> case. In my document, there are no attributes - the same changes
> should be made to attribute validation routines.
> 
> I don't think this has anything to do with the case statement.

I agree. I ran cProfile over just the tokenizer step; essentially

tokenizer = html5lib.tokenizer.HTMLStream(htmldata)
for tok in tokenizer:
    pass

It mostly *isn't* tokenizer.py that's taking the most time, it's
inputstream.py. (There is one exception:
tokenizer.py:HTMLStream.__init__ constructs a dictionary of states
each time -- this is unnecessary, replace all expressions like
self.states["attributeName"] with self.attributeNameState.)

I've done several optimisations -- I'll upload the patch to the
html5lib issue tracker. In particular,

* The .position property of EncodingBytes is used a lot. Every
self.position +=1 calls getPosition() and setPosition(). Another
getPosition() call is done in the self.currentByte property. Most of
these can be optimised away by using methods that move the position
and return the current byte.

* In HTMLInputStream, the current line number and column are updated
every time a new character is read with .char(). The current position
is *only* used in error reporting, so I reworked it to only calculate
the position when .position() is called, by keeping track of the
number of lines in previous read chunks, and computing the number of
lines to the current offset in the current chunk.

These give me about a 20% speedup.

This just illustrates that the first step in optimisation is profiling :D

As other posters have said, slurping the whole document into memory
and using a regexp-based parser (such as pyparsing) would likely give
you the largest speedups. If you want to keep the chunk- based
approach, you can still use regexp's, but you'd have to think about
matching on chunk boundaries. One way would be to guarantee a minimum
number of characters available, say 10 or 50 (unless end-of-file, of
course) -- long enough such that any *constant* string you'd want to
match like <![CDATA[ would fit inside that guaranteed length. Any
arbitrary-length tokens (such as attribute names and values) would be
matched, not with regexps like [a-z]+, but with [a-z]{1,10} (match
[a-z] from 1 to 10 times), and joining the individual matches together
to make one token.

Since html5lib has several implementations for several languages, it
may actually be worth it to generate lexers for each language from one
specification file.

Take care,
David M. Cooke <david.m.cooke at gmail.com>



From ldo at geek-central.gen.new_zealand  Mon Jul  6 04:29:04 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 20:29:04 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
Message-ID: <h2sckg$eng$2@lust.ihug.co.nz>

In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim Golden 
wrote:

> The difficulty here is knowing where to put such a warning.
> You obviously can't put it against the "++" operator as such
> because... there isn't one.

This bug is an epiphenomenon. :)



From wuwei23 at gmail.com  Mon Jul  6 04:30:03 2009
From: wuwei23 at gmail.com (alex23)
Date: Mon, 6 Jul 2009 01:30:03 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com> 
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
Message-ID: <19f3d19d-c4bc-4f94-8387-febe624245a2@p18g2000pra.googlegroups.com>

On Jul 6, 5:56?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Gabriel Genellina wrote:
> > In this case, a note in the documentation warning about the potential
> > confusion would be fine.
>
> The difficulty here is knowing where to put such a warning.
> You obviously can't put it against the "++" operator as such
> because... there isn't one. You could put it against the unary
> plus operator, but who's going to look there? :)

The problem is: where do you stop? If you're going to add something to
the documentation to address every expectation someone might hold
coming from another language, the docs are going to get pretty big.

I think a language should be intuitive within itself, but not be
required to be intuitable based on _other_ languages (unless, of
course, that's an objective of the language). If I expect something in
language-A to operate the same way as completely-unrelated-language-B,
I'd see that as a failing on my behalf, especially if I hadn't read
language-A's documentation first. I'm not adverse to one language
being _explained_ in terms of another, but would much prefer to see
those relegated to "Python for <x> programmers" articles rather than
in the main docs themselves.


From ldo at geek-central.gen.new_zealand  Mon Jul  6 04:32:34 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 06 Jul 2009 20:32:34 +1200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
Message-ID: <h2scr3$eng$3@lust.ihug.co.nz>

In message <4a4f91f9$0$1587$742ec2ed at news.sonic.net>, John Nagle wrote:

> ("It should be written in C" is not an acceptable answer.)

I don't see why not. State machines that have to process input byte by byte 
are well known to be impossible to implement efficiently in high-level 
languages. That's why lex/flex isn't worth using. Even GCC has been moving 
to hand-coded parsers, first the lexical analyzer, and more recently even 
for the syntax parser (getting rid of yacc/bison), certainly for C.



From clp2 at rebertia.com  Mon Jul  6 04:32:51 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 01:32:51 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2sckg$eng$2@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
Message-ID: <50697b2c0907060132w592ce54dt3c9392b764639bb2@mail.gmail.com>

On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim Golden
> wrote:
>
>> The difficulty here is knowing where to put such a warning.
>> You obviously can't put it against the "++" operator as such
>> because... there isn't one.
>
> This bug is an epiphenomenon. :)

Well, like I suggested, it /could/ be made an operator (or rather, a
lexer token) which just causes a compile/parse error.

Cheers,
Chris
-- 
http://blog.rebertia.com


From simon at brunningonline.net  Mon Jul  6 05:02:08 2009
From: simon at brunningonline.net (Simon Brunning)
Date: Mon, 6 Jul 2009 10:02:08 +0100
Subject: generation of keyboard events
In-Reply-To: <d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
	<d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
Message-ID: <8c7f10c60907060202v60c7ea0ct51749bbaf0f81bb6@mail.gmail.com>

2009/7/6 RAM <serverin2000 at yahoo.com>:

> I am trying to do this on windows. My program(executable) has been
> written in VC++ and when I run this program, I need to click on one
> button on the program GUI i,e just I am entering "Enter key" on the
> key board. But this needs manual process. So i need to write a python
> script which invokes my program and pass "Enter key" event to my
> program so that it runs without manual intervention.

Try <http://pywinauto.openqa.org/>.

-- 
Cheers,
Simon B.


From sjmachin at lexicon.net  Mon Jul  6 05:15:57 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 6 Jul 2009 02:15:57 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <2e02da2c-28d5-4ce5-9aa0-2827ba7110d3@12g2000pri.googlegroups.com>

On Jul 6, 12:32?pm, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> I wonder how many people have been tripped up by the fact that
>
> ? ? ++n
>
> and
>
> ? ? --n
>
> fail silently for numeric-valued n.

What fail? In Python, ++n and --n are fatuous expressions which
SUCCEED silently except for rare circiumstances e.g. --n will cause an
overflow exception on older CPython versions if isinstance(n, int) and
n == -sys.maxint - 1.



From vilya.harvey at gmail.com  Mon Jul  6 05:21:07 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Mon, 6 Jul 2009 10:21:07 +0100
Subject: Why is my code faster with append() in a loop than with a large 
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <6aef848f0907060221t6a44e10bga5a7798855779b5@mail.gmail.com>

2009/7/6 Xavier Ho <contact at xavierho.com>:
> Why is version B of the code faster than version A? (Only three lines
> different)

Here's a guess:

As the number you're testing gets larger, version A is creating very
big list. I'm not sure exactly how much overhead each list entry has
in python, but I guess it's at least 8 bytes: a 32-bit reference for
each list entry, and 32 bits to hold the int value (assuming a 32-bit
version of python). The solution you're looking for is a large 8 digit
number; let's say 80,000,000, for the sake of easy calculation. That
means, as you get close to the solution, you'll be trying to allocate
almost 640 Mb of memory for every number you're checking. That's going
to make the garbage collector work extremely hard. Also, depending on
how much memory your computer has free, you'll probably start hitting
virtual memory too, which will slow you down even further. Finally,
the reduce step has to process all 80,000,000 elements which is
clearly going to take a while.

Version b creates a list which is only as long as the largest prime
factor, so at worst the list size will be approx. sqrt(80,000,000),
which is approx. 8900 elements or approx. 72 Kb or memory - a much
more manageable size.

Hope that helps,

Vil.


From tjreedy at udel.edu  Mon Jul  6 05:36:27 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 05:36:27 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <h2sgiq$6ud$1@ger.gmane.org>

Gabriel Genellina wrote:
>
> In this case, a note in the documentation warning about the potential 
> confusion would be fine.

How would that help someone who does not read the doc?




From mooniitk at gmail.com  Mon Jul  6 05:55:26 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Mon, 6 Jul 2009 11:55:26 +0200
Subject: Tree structure consuming lot of memory
Message-ID: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>

Hi,

I am creating a tree data-structure in python; with nodes of the tree
created by a simple class :

class Node :
       def __init__(self , .... other attributes):
              # initialise the attributes here!!

But the problem is I am working with a huge tree (millions of nodes); and
each node is consuming much more memory than it should. After a little
analysis, I found out that in general it uses about 1.4 kb of memory for
each node!!
I will be grateful if someone could help me optimize the memory usage.
Thanks.

Regards,
Mayank


-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/a066fe29/attachment-0001.html>

From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 05:58:21 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 06 Jul 2009 09:58:21 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
Message-ID: <006da5a2$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 02:19:51 -0300, Gabriel Genellina wrote:

> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
> <steve at remove-this-cybersource.com.au> escribi?:
>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>
>>> I wonder how many people have been tripped up by the fact that
>>>
>>>     ++n
>>>
>>> and
>>>
>>>     --n
>>>
>>> fail silently for numeric-valued n.
>>
>> What do you mean, "fail silently"? They do exactly what you should
>> expect:
>>>>> ++5  # positive of a positive number is positive
>>
>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>> that are buggy, not Python.
> 
> Well, those expectations are taken seriously when new features are
> introduced into the language - and sometimes the feature is dismissed
> just because it would be confusing for some. If a += 1 works, expecting
> ++a to have the same meaning is very reasonable (for those coming from
> languages with a ++ operator, like C or Java) - more when ++a is a
> perfectly valid expression. If this issue isn't listed under the various
> "Python gotchas" articles, it should...

The fact that it isn't suggests strongly to me that it isn't that common 
a surprise even for Java and C programmers. This is the first time I've 
seen anyone raise it as an issue.

There are plenty of other languages other than Java and C. If we start 
listing every feature of Python that's different from some other 
language, we'll never end.

For what it's worth, Ruby appears to behave the same as Python:

$ irb
irb(main):001:0> n = 5
=> 5
irb(main):002:0> ++n
=> 5
irb(main):003:0> --n
=> 5
irb(main):004:0> -+n
=> -5



-- 
Steven


From clp2 at rebertia.com  Mon Jul  6 06:03:00 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 03:03:00 -0700
Subject: Tree structure consuming lot of memory
In-Reply-To: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
Message-ID: <50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>

On Mon, Jul 6, 2009 at 2:55 AM, mayank gupta<mooniitk at gmail.com> wrote:
> Hi,
>
> I am creating a tree data-structure in python; with nodes of the tree
> created by a simple class :
>
> class Node :
> ?????? def __init__(self , .... other attributes):
> ????????????? # initialise the attributes here!!
>
> But the problem is I am working with a huge tree (millions of nodes); and
> each node is consuming much more memory than it should. After a little
> analysis, I found out that in general it uses about 1.4 kb of memory for
> each node!!
> I will be grateful if someone could help me optimize the memory usage.

(1) Use __slots__ (see http://docs.python.org/reference/datamodel.html#slots)
(2) Use some data structure other than a tree
(3) Rewrite your Node/Tree implementation in C

Cheers,
Chris
-- 
http://blog.rebertia.com


From davea at dejaviewphoto.com  Mon Jul  6 06:09:46 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Mon, 06 Jul 2009 06:09:46 -0400
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
Message-ID: <4A51CD6A.2010106@dejaviewphoto.com>

Xavier Ho wrote:
> (Here's a short version of the long version below if you don't want to
> read:)
>
> Why is version B of the code faster than version A? (Only three lines
> different)
>
> Version A: http://pastebin.com/f14561243
> Version B: http://pastebin.com/f1f657afc
>
> ------------------------------------------------
>
> I was doing the problems on Project Euler for practice with Python last
> night. Problem 12 was to find the value of the first triangular number that
> has over 500 divisors.
> =========================================================================================
>
> The sequence of triangle numbers is generated by adding the natural numbers.
> So the 7[image: ^(]th[image: )] triangle number would be 1 + 2 + 3 + 4 + 5 +
> 6 + 7 = 28. The first ten terms would be:
>
> 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
>
> Let us list the factors of the first seven triangle numbers:
>
> * 1*: 1
> * 3*: 1,3
> * 6*: 1,2,3,6
> *10*: 1,2,5,10
> *15*: 1,3,5,15
> *21*: 1,3,7,21
> *28*: 1,2,4,7,14,28
>
> We can see that 28 is the first triangle number to have over five divisors.
>
> What is the value of the first triangle number to have over five hundred
> divisors?
> =========================================================================================
>
> My initial code was to loop through from 1 to half the number and see which
> were divisors, and as I find them I store them in a list. That would have
> taken days.
>
> My second try was factorising the number each time, and count the divisors
> using the powers of each factor, plus 1, and multiply together.
> The code is here (Version A): http://pastebin.com/f14561243
>
> This worked, but it took overnight to compute. Before I went to bed a friend
> of mine caught me online, and apparently left me a working version under 8
> seconds with only 3 line difference.
> The code is here (Version B): http://pastebin.com/f1f657afc
>
> That was amazing. But I have no idea why his edit makes it so much faster. I
> did a test to see whether if append() was faster (which I doubted) than
> defining a list with a large size to begin with, and I was right:
> http://pastebin.com/f4b46d0db
> Which shows that appending is 40x slower, and was expected. But I still
> can't puzzle out why his use of appending in Version B was so much faster
> than mine.
>
> Any insights would be welcome. I'm going on a family trip, though, so my
> replies may delay.
>
> Best regards,
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
>   
Just by inspection, it would seem the bottleneck in your first version 
is that you return a huge list of nearly all zeroes, from factorize().  
This slows down countDivisors() a great deal.

It would probably save some time to not bother storing the zeroes in the 
list at all.  And it should help if you were to step through a list of 
primes, rather than trying every possible int.  Or at least constrain 
yourself to odd numbers (after the initial case of 2).

DaveA


From mooniitk at gmail.com  Mon Jul  6 06:12:06 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Mon, 6 Jul 2009 12:12:06 +0200
Subject: Tree structure consuming lot of memory
In-Reply-To: <50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>
Message-ID: <ff4d16090907060312n6df077capcce97ddd0786983@mail.gmail.com>

Thanks for the other possibilites. I would consider option (2) and (3) to
improve my code.

But out of curiosity, I would still like to know why does an object of a
Python-class consume "so" much of memory (1.4 kb), and this memory usage has
nothing to do with its attributes.

Thanks

Regards.

On Mon, Jul 6, 2009 at 12:03 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Mon, Jul 6, 2009 at 2:55 AM, mayank gupta<mooniitk at gmail.com> wrote:
> > Hi,
> >
> > I am creating a tree data-structure in python; with nodes of the tree
> > created by a simple class :
> >
> > class Node :
> >        def __init__(self , .... other attributes):
> >               # initialise the attributes here!!
> >
> > But the problem is I am working with a huge tree (millions of nodes); and
> > each node is consuming much more memory than it should. After a little
> > analysis, I found out that in general it uses about 1.4 kb of memory for
> > each node!!
> > I will be grateful if someone could help me optimize the memory usage.
>
> (1) Use __slots__ (see
> http://docs.python.org/reference/datamodel.html#slots)
> (2) Use some data structure other than a tree
> (3) Rewrite your Node/Tree implementation in C
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>



-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/a1061b4a/attachment-0001.html>

From p.f.moore at gmail.com  Mon Jul  6 08:05:02 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Mon, 6 Jul 2009 13:05:02 +0100
Subject: Opening a SQLite database in readonly mode
Message-ID: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>

The SQLite documentation mentions a flag, SQLITE_OPEN_READONLY, to
open a database read only. I can't find any equivalent documented in
the Python standard library documentation for the sqlite3 module (or,
for that matter, on the pysqlite library's website).

Is it possible to open a sqlite database in readonly mode, in Python?

Thanks,
Paul.


From mail at microcorp.co.za  Mon Jul  6 08:12:42 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Mon, 6 Jul 2009 14:12:42 +0200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com><op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<h2sgiq$6ud$1@ger.gmane.org>
Message-ID: <00df01c9fe33$10c36d80$0d00a8c0@Hendrik>

"Terry Reedy" <t...j at ..el.edu> wrote:

> Gabriel Genellina wrote:
> >
> > In this case, a note in the documentation warning about the potential 
> > confusion would be fine.
> 
> How would that help someone who does not read the doc?

It obviously won't.

All it will do, is that it will enable people on this group,
who may read the manual, to tell people who complain,
to RTFM.

 I agree that it would be a good idea to make it an 
error, or a warning - "this might not do what you
think it does", or an "are you sure?" exception.

  :-)

- Hendrik





From contact at xavierho.com  Mon Jul  6 08:12:58 2009
From: contact at xavierho.com (Xavier Ho)
Date: Mon, 6 Jul 2009 20:12:58 +0800
Subject: Why is my code faster with append() in a loop than with a large 
	list?
In-Reply-To: <4A51CD6A.2010106@dejaviewphoto.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<4A51CD6A.2010106@dejaviewphoto.com>
Message-ID: <2d56febf0907060512m794c2468sfa01cf332df3167a@mail.gmail.com>

Thanks for the response all, I finally got my 'net working on the mountains,
and I think your reasons are quite sound. I'll keep that in mind for the
future.

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Mon, Jul 6, 2009 at 6:09 PM, Dave Angel <davea at dejaviewphoto.com> wrote:

> Xavier Ho wrote:
>
>> (Here's a short version of the long version below if you don't want to
>> read:)
>>
>> Why is version B of the code faster than version A? (Only three lines
>> different)
>>
>> Version A: http://pastebin.com/f14561243
>> Version B: http://pastebin.com/f1f657afc
>>
>> ------------------------------------------------
>>
>> I was doing the problems on Project Euler for practice with Python last
>> night. Problem 12 was to find the value of the first triangular number
>> that
>> has over 500 divisors.
>>
>> =========================================================================================
>>
>> The sequence of triangle numbers is generated by adding the natural
>> numbers.
>> So the 7[image: ^(]th[image: )] triangle number would be 1 + 2 + 3 + 4 + 5
>> +
>>
>> 6 + 7 = 28. The first ten terms would be:
>>
>> 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
>>
>> Let us list the factors of the first seven triangle numbers:
>>
>> * 1*: 1
>> * 3*: 1,3
>> * 6*: 1,2,3,6
>> *10*: 1,2,5,10
>> *15*: 1,3,5,15
>> *21*: 1,3,7,21
>> *28*: 1,2,4,7,14,28
>>
>> We can see that 28 is the first triangle number to have over five
>> divisors.
>>
>> What is the value of the first triangle number to have over five hundred
>> divisors?
>>
>> =========================================================================================
>>
>> My initial code was to loop through from 1 to half the number and see
>> which
>> were divisors, and as I find them I store them in a list. That would have
>> taken days.
>>
>> My second try was factorising the number each time, and count the divisors
>> using the powers of each factor, plus 1, and multiply together.
>> The code is here (Version A): http://pastebin.com/f14561243
>>
>> This worked, but it took overnight to compute. Before I went to bed a
>> friend
>> of mine caught me online, and apparently left me a working version under 8
>> seconds with only 3 line difference.
>> The code is here (Version B): http://pastebin.com/f1f657afc
>>
>> That was amazing. But I have no idea why his edit makes it so much faster.
>> I
>> did a test to see whether if append() was faster (which I doubted) than
>> defining a list with a large size to begin with, and I was right:
>> http://pastebin.com/f4b46d0db
>> Which shows that appending is 40x slower, and was expected. But I still
>> can't puzzle out why his use of appending in Version B was so much faster
>> than mine.
>>
>> Any insights would be welcome. I'm going on a family trip, though, so my
>> replies may delay.
>>
>> Best regards,
>>
>> Ching-Yun "Xavier" Ho, Technical Artist
>>
>> Contact Information
>> Mobile: (+61) 04 3335 4748
>> Skype ID: SpaXe85
>> Email: contact at xavierho.com
>> Website: http://xavierho.com/
>>
>>
>>
> Just by inspection, it would seem the bottleneck in your first version is
> that you return a huge list of nearly all zeroes, from factorize().  This
> slows down countDivisors() a great deal.
>
> It would probably save some time to not bother storing the zeroes in the
> list at all.  And it should help if you were to step through a list of
> primes, rather than trying every possible int.  Or at least constrain
> yourself to odd numbers (after the initial case of 2).
>
> DaveA
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/2a336b8d/attachment-0001.html>

From pm567426 at gmail.com  Mon Jul  6 08:24:43 2009
From: pm567426 at gmail.com (Pedram)
Date: Mon, 6 Jul 2009 05:24:43 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
Message-ID: <b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com>

OK, fine, I read longobject.c at last! :)
I found that longobject is a structure like this:

struct _longobject {
    struct _object *_ob_next;
    struct _object *_ob_prev;
    Py_ssize_t ob_refcnt;
    struct _typeobject *ob_type;
    digit ob_digit[1];
}

And a digit is a 15-item array of C's unsigned short integers.
Am I right? Or I missed something! Is this structure is constant in
all environments (Linux, Windows, Mobiles, etc.)?


From jeanmichel at sequans.com  Mon Jul  6 08:32:10 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 06 Jul 2009 14:32:10 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2nqpf$d91$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<7xk52p4tgg.fsf@ruckus.brouhaha.com>
	<h2nqpf$d91$1@reader1.panix.com>
Message-ID: <4A51EECA.10509@sequans.com>

kj wrote:
>  I've rewritten it like this:
>
>     sense = cmp(func(hi), func(lo))
>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>
> Thanks for your feedback!
>
> kj
>   

As already said before, unlike other languages, sense in english does 
**not** mean direction. You should rewrite this part using a better 
name. Wrong informations are far worse than no information at all.

JM


From Scott.Daniels at Acm.Org  Mon Jul  6 08:33:02 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 05:33:02 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <mailman.2673.1246866666.8015.python-list@python.org>
References: <h2l36k$q5l$1@reader1.panix.com>	<f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
	<mailman.2673.1246866666.8015.python-list@python.org>
Message-ID: <fMKdnf0dlOXTcMzXnZ2dnUVZ_t2dnZ2d@pdx.net>

Andre Engels wrote:
> On Mon, Jul 6, 2009 at 9:44 AM, Martin Vilcans<martin at librador.com> wrote:
>> On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
>>> I'm will be teaching a programming class to novices, and I've run
>>> into a clear conflict between two of the principles I'd like to
>>> teach: code clarity vs. code reuse.  I'd love your opinion about
>>> it.
>> In general, code clarity is more important than reusability.
>> Unfortunately, many novice programmers have the opposite impression. I
>> have seen too much convoluted code written by beginners who try to
>> make the code generic. Writing simple, clear, to-the-point code is
>> hard enough as it is, even when not aiming at making it reusable.
>>
>> If in the future you see an opportunity to reuse the code, then and
>> only then is the time to make it generic.
> 
> Not just that, when you actually get to that point, making simple and
> clear code generic is often easier than making
> complicated-and-supposedly-generic code that little bit more generic
> that you need.

First, a quote which took me a bit to find:
     Thomas William K?rner paraphrasing Polya and Svego
     in A Companion to Analysis:
         Recalling that 'once is a trick, twice is a method,
         thrice is a theorem, and four times a theory,' we
         seek to codify this insight.

Let us apply this insight:
     Suppose in writing code, we pretty much go with that.
A method is something you notice, a theorem is a function, and
a theory is a generalized function.

Even though we like DRY ("don't repeat yourself") as a maxim, let
it go the first time and wait until you see the pattern (a possible
function).  I'd go with a function first, a pair of functions, and
only then look to abstracting the function.

--Scott David Daniels
Scott.Daniels at Acm.Org


From Scott.Daniels at Acm.Org  Mon Jul  6 08:47:18 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 05:47:18 -0700
Subject: Creating alot of class instances?
In-Reply-To: <006d4e86$0$9711$c3e8da3@news.astraweb.com>
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>	<mailman.2652.1246830168.8015.python-list@python.org>	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <comdnVhXl4M6bczXnZ2dnUVZ_g2dnZ2d@pdx.net>

Steven D'Aprano wrote:
> ... That's the Wrong Way to do it --
> you're using a screwdriver to hammer a nail....

Don't knock tool abuse (though I agree with you here).
Sometimes tool abuse can produce good results.  For
example, using hammers to drive screws for temporary
strong holds led to making better nails.

--Scott David Daniels
Scott.Daniels at Acm.Org


From ronn.ross at gmail.com  Mon Jul  6 08:47:30 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Mon, 6 Jul 2009 08:47:30 -0400
Subject: VirtualEnv
Message-ID: <9c8c445f0907060547g5a279821n4cd31efe9231887b@mail.gmail.com>

I'm attempting to write a bootstrap script for virtualenv. I just want to do
a couple of easy_install's after the environment is created. It was fairly
easy to create the script, but I can't figure out how to implement it. The
documentation was not of much help. Can someone please point me in the right
direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/e9494afe/attachment-0001.html>

From jeanmichel at sequans.com  Mon Jul  6 08:54:03 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 06 Jul 2009 14:54:03 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <006201c9fd48$666d94e0$0d00a8c0@Hendrik>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<006201c9fd48$666d94e0$0d00a8c0@Hendrik>
Message-ID: <4A51F3EB.1080509@sequans.com>


> protocol = {"start":initialiser,"hunt":hunter,"classify":classifier,....other
> states}
>
> def state_machine():
>     next_step = protocol["start"]()
>     while True:
>         next_step = protocol[next_step]()
>
>   
Woot ! I'll keep this one in my mind, while I may not be that concerned 
by speed unlike the OP, I still find this way of doing very simple and 
so intuitive (one will successfully argue how I was not figuring this 
out by myself if it was so intuitive).
Anyway I wanted to participated to this thread, as soon as I saw 'due to 
python limitations' in the title, I foretold a hell of a thread ! This 
is just provocation ! :-)

JM


From pdpinheiro at gmail.com  Mon Jul  6 09:38:13 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Mon, 6 Jul 2009 06:38:13 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com><op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<h2sgiq$6ud$1@ger.gmane.org>
	<mailman.2687.1246882531.8015.python-list@python.org>
Message-ID: <bdfa2d84-e4ed-4197-8bf7-83dc28d131e7@26g2000yqk.googlegroups.com>

On Jul 6, 1:12?pm, "Hendrik van Rooyen" <m... at microcorp.co.za> wrote:
> "Terry Reedy" <t...j at ..el.edu> wrote:
> > Gabriel Genellina wrote:
>
> > > In this case, a note in the documentation warning about the potential
> > > confusion would be fine.
>
> > How would that help someone who does not read the doc?
>
> It obviously won't.
>
> All it will do, is that it will enable people on this group,
> who may read the manual, to tell people who complain,
> to RTFM.
>
> ?I agree that it would be a good idea to make it an
> error, or a warning - "this might not do what you
> think it does", or an "are you sure?" exception.
>
> ? :-)
>
> - Hendrik

I dunno. Specifically recognizing (and emitting code code for) a token
that's not actually part of the language because people coming from
other languages think it exists seems like the start of a fustercluck.


From dickinsm at gmail.com  Mon Jul  6 09:46:05 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Mon, 6 Jul 2009 06:46:05 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com>
Message-ID: <088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com>

On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
> OK, fine, I read longobject.c at last! :)
> I found that longobject is a structure like this:
>
> struct _longobject {
> ? ? struct _object *_ob_next;
> ? ? struct _object *_ob_prev;

For current CPython, these two fields are only present in debug
builds;  for a normal build they won't exist.

> ? ? Py_ssize_t ob_refcnt;
> ? ? struct _typeobject *ob_type;

You're missing an important field here (see the definition of
PyObject_VAR_HEAD):

    Py_ssize_t ob_size; /* Number of items in variable part */

For the current implementation of Python longs, the absolute value of
this field gives the number of digits in the long;  the sign gives the
sign of the long (0L is represented with zero digits).

> ? ? digit ob_digit[1];

Right.  This is an example of the so-called 'struct hack' in C; it
looks as though there's just a single digit, but what's intended here
is that there's an array of digits tacked onto the end of the struct;
for any given PyLongObject, the size of this array is determined at
runtime.  (C99 allows you to write this as simply ob_digit[], but not
all compilers support this yet.)

> }

> And a digit is a 15-item array of C's unsigned short integers.

No: a digit is a single unsigned short, which is used to store 15 bits
of the Python long.  Python longs are stored in sign-magnitude format,
in base 2**15.  So each of the base 2**15 'digits' is an integer in
the range [0, 32767).  The unsigned short type is used to store those
digits.

Exception: for Python 2.7+ or Python 3.1+, on 64-bit machines, Python
longs are stored in base 2**30 instead of base 2**15, using a 32-bit
unsigned integer type in place of unsigned short.

> Is this structure is constant in
> all environments (Linux, Windows, Mobiles, etc.)?

I think it would be dangerous to rely on this struct staying constant,
even just for CPython.  It's entirely possible that the representation
of Python longs could change in Python 2.8 or 3.2.  You should use the
public, documented C-API whenever possible.

Mark


From philip at semanchuk.com  Mon Jul  6 09:51:58 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 09:51:58 -0400
Subject: How to map size_t using ctypes?
Message-ID: <A30412CC-0922-49EF-878F-D1CD344B37CB@semanchuk.com>

Hi all,
I can't figure out how to map a C variable of size_t via Python's  
ctypes module. Let's say I have a C function like this:

void populate_big_array(double *the_array, size_t element_count) {...}

How would I pass parameter 2? A long (or ulong) will (probably) work  
(on most platforms), but I like my code to be more robust than that.  
Furthermore, this is scientific code and it's entirely possible that  
someone will want to pass a huge array with more elements than can be  
described by a 32-bit long.


Suggestions appreciated.

Thanks
Philip


From Scott.Daniels at Acm.Org  Mon Jul  6 09:59:44 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 06:59:44 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <h2s5rm$m95$01$1@news.t-online.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<025f4dbf$0$20657$c3e8da3@news.astraweb.com>
	<025f5b0d$0$20657$c3e8da3@news.astraweb.com>
	<600d2270-2c02-4709-b636-6b18b36da913@l31g2000yqb.googlegroups.com>
	<tuednRA-t5avLNLXnZ2dnUVZ_gGdnZ2d@pdx.net>
	<d35b3e22-4e68-42b3-890d-d299b01ce987@18g2000yqa.googlegroups.com>
	<4A4FDCAF.8010209@Acm.Org>
	<UfidnTF_Z5KJ2czXnZ2dnUVZ_tKdnZ2d@pdx.net>
	<h2s5rm$m95$01$1@news.t-online.com>
Message-ID: <4A520350.9000806@Acm.Org>

Peter Otten wrote:
> Scott David Daniels wrote:
> 
>> Scott David Daniels wrote:
> 
>>      t = timeit.Timer('sum(part[:-1]==part[1:])',
>>                       'from __main__ import part')
> 
> What happens if you calculate the sum in numpy? Try
> 
> t = timeit.Timer('(part[:-1]==part[1:]).sum()',
>                  'from __main__ import part')

Good idea, I hadn't thought of adding numpy bools.
     (part[:-1]==part[1:]).sum()
is only a slight improvement over
     len(part[part[:-1]==part[1:]])
when there are few elements, but it is almost twice
as fast when there are a lot (reflecting the work
of allocating and copying).

 >>> import numpy
 >>> import timeit
 >>> original = numpy.random.normal(0, 100, (1000, 1000)).astype(int)
 >>> data = original.flatten()
 >>> data.sort()
 >>> t = timeit.Timer('sum(part[:-1]==part[1:])',
                      'from __main__ import part')
 >>> u = timeit.Timer('len(part[part[:-1]==part[1:]])',
                      'from __main__ import part')
 >>> v = timeit.Timer('(part[:-1]==part[1:]).sum()',
                      'from __main__ import part')

 >>> part = data[::100]
 >>> (part[:-1]==part[1:]).sum()
9390
 >>> t.repeat(3, 10)
[0.56368281443587875, 0.55615057220961717, 0.55465764503594528]
 >>> u.repeat(3, 1000)
[0.89576580263690175, 0.89276374511291579, 0.8937328626963108]
 >>> v.repeat(3, 1000)
[0.24798598704592223, 0.24715431709898894, 0.24498979618920202]
 >>>
 >>> part = original.flatten()[::100]
 >>> (part[:-1]==part[1:]).sum()
27
 >>> t.repeat(3, 10)
[0.57576898739921489, 0.56410158274297828, 0.56988248506445416]
 >>> u.repeat(3, 1000)
[0.27312186325366383, 0.27315007913011868, 0.27214492344683094]
 >>> v.repeat(3, 1000)
[0.28410342655297427, 0.28374053126867693, 0.28318990262732768]
 >>>

Net result: go back to former definition of candidates (a number,
not the actual entries), but calculate that number as matches.sum(),
not len(part[matches]).

Now the latest version of this (compressed) code:
 >     ...
 >     sampled = data[::stride]
 >     matches = sampled[:-1] == sampled[1:]
 >     candidates = sum(matches) # count identified matches
 >     while candidates > N * 10: # 10 -- heuristic
 >         stride *= 2 # # heuristic increase
 >         sampled = data[::stride]
 >         matches = sampled[:-1] == sampled[1:]
 >         candidates = sum(matches)
 >     while candidates < N * 3: # heuristic slop for long runs
 >         stride //= 2 # heuristic decrease
 >         sampled = data[::stride]
 >         matches = sampled[:-1] == sampled[1:]
 >         candidates = sum(matches)
 >     former = None
 >     past = 0
 >     for value in sampled[matches]:
 >         ...
is:
       ...
       sampled = data[::stride]
       matches = sampled[:-1] == sampled[1:]
       candidates = matches.sum() # count identified matches
       while candidates > N * 10: # 10 -- heuristic
           stride *= 2 # # heuristic increase
           sampled = data[::stride]
           matches = sampled[:-1] == sampled[1:]
           candidates = matches.sum()
       while candidates < N * 3: # heuristic slop for long runs
           stride //= 2 # heuristic decrease
           sampled = data[::stride]
           matches = sampled[:-1] == sampled[1:]
           candidates = matches.sum()
       former = None
       past = 0
       for value in sampled[matches]:
           ...

Now I think I can let this problem go, esp. since it was
mclovin's problem in the first place.

--Scott David Daniels
Scott.Daniels at Acm.Org


From dickinsm at gmail.com  Mon Jul  6 10:01:42 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Mon, 6 Jul 2009 07:01:42 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>

On Jul 6, 3:32?am, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> I wonder how many people have been tripped up by the fact that
>
> ? ? ++n
>
> and
>
> ? ? --n
>
> fail silently for numeric-valued n.

Recent python-ideas discussion on this subject:

http://mail.python.org/pipermail/python-ideas/2009-March/003741.html

Mark


From mail at microcorp.co.za  Mon Jul  6 10:04:30 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Mon, 6 Jul 2009 16:04:30 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<006201c9fd48$666d94e0$0d00a8c0@Hendrik>
	<4A51F3EB.1080509@sequans.com>
Message-ID: <000901c9fe42$b026cfc0$0d00a8c0@Hendrik>

"Jean-Michel Pichavant" <jeanmichel at s....ns.com> wrote:

> Woot ! I'll keep this one in my mind, while I may not be that concerned 
> by speed unlike the OP, I still find this way of doing very simple and 
> so intuitive (one will successfully argue how I was not figuring this 
> out by myself if it was so intuitive).
> Anyway I wanted to participated to this thread, as soon as I saw 'due to 
> python limitations' in the title, I foretold a hell of a thread ! This 
> is just provocation ! :-)

The OP was not being provocative - he has a real problem, and the
code he is complaining about already does more or less what my
snippet showed, as I rushed in where angels fear to tread...

The bit that was not clearly shown in what I proposed, is that you
should stay in the individual states, testing for the reasons for the
state transitions, until it is time to change - so there is a while loop
in each of the individual states too.  It becomes a terribly big structure
if you have a lot of states, it duplicates a lot of tests across the different
states, and it is very awkward if the states nest.

Have a look at the one without the dict too - it is even faster as it
avoids the dict lookup.

That, however, is a bit like assembler code, as it kind of "jumps" 
from state to state, and there is no central thing to show what does,
and what does not, belong together, as there is no dict.  Not an easy
beast to fix if it's big and it's wrong.

- Hendrik





From "sandrodll[remove]" at googlemail.com  Mon Jul  6 10:21:01 2009
From: "sandrodll[remove]" at googlemail.com (gialloporpora)
Date: Mon, 06 Jul 2009 16:21:01 +0200
Subject: Help to find a regular expression to parse po file
Message-ID: <4A52084D.1010900@googlemail.com>

Hi all,
I would like to extract string from a PO file. To do this I have created 
a little python function to parse po file and extract string:

import re
regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
m=r.findall(s)

where s is a po file like this:

msgctxt "write ubiquity commands.description"
msgid "Takes you to the Ubiquity <a 
href=\"chrome://ubiquity/content/editor.html\">command editor</a> page."
msgstr "Apre l'<a href=\"chrome://ubiquity/content/editor.html\">editor 
dei comandi</a> di Ubiquity."


#. list ubiquity commands command:
#. use | to separate multiple name values:
msgctxt "list ubiquity commands.names"
msgid "list ubiquity commands"
msgstr "elenco comandi disponibili"

msgctxt "list ubiquity commands.description"
msgid "Opens <a href=\"chrome://ubiquity/content/cmdlist.html\">the 
list</a>\n"
"      of all Ubiquity commands available and what they all do."
msgstr "Apre una <a 
href=\"chrome://ubiquity/content/cmdlist.html\">pagina</a>\n"
"      in cui sono elencati tutti i comandi disponibili e per ognuno 
viene spiegato in breve a cosa serve."



#. change ubiquity settings command:
#. use | to separate multiple name values:
msgctxt "change ubiquity settings.names"
msgid "change ubiquity settings|change ubiquity preferences|change 
ubiquity skin"
msgstr "modifica impostazioni di ubiquity|modifica preferenze di 
ubiquity|modifica tema di ubiquity"

msgctxt "change ubiquity settings.description"
msgid "Takes you to the <a 
href=\"chrome://ubiquity/content/settings.html\">settings</a> page,\n"
"      where you can change your skin, key combinations, etc."
msgstr "Apre la pagina  <a 
href=\"chrome://ubiquity/content/settings.html\">delle impostazioni</a> 
di Ubiquity,\n"
"     dalla quale ?? possibile modificare la combinazione da tastiera 
utilizzata per richiamare Ubiquity, il tema, ecc."



but, obviusly,  with the code above the  last string is not matched. If 
I use re.DOTALL to match also new line character it not works because it 
match the entire file, I would like to stop the matching when "msgstr" 
is found.

regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n\\n",re.DOTALL)

is it possible or not ?






From python at mrabarnett.plus.com  Mon Jul  6 10:22:23 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 15:22:23 +0100
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <4A51CD6A.2010106@dejaviewphoto.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<4A51CD6A.2010106@dejaviewphoto.com>
Message-ID: <4A52089F.7020301@mrabarnett.plus.com>

Dave Angel wrote:
[snip]
> It would probably save some time to not bother storing the zeroes in the 
> list at all.  And it should help if you were to step through a list of 
> primes, rather than trying every possible int.  Or at least constrain 
> yourself to odd numbers (after the initial case of 2).
> 
Or stop looking for more factors when you've passed the square root of
num. I don't know what effect there'll be on the time if you recalculate
the square root when num changes (expensive calculation vs smaller
search space).


From rhodri at wildebst.demon.co.uk  Mon Jul  6 11:00:59 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Mon, 06 Jul 2009 16:00:59 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <006da5a2$0$9711$c3e8da3@news.astraweb.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <op.uwninxtza8ncjz@gnudebst>

On Mon, 06 Jul 2009 10:58:21 +0100, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> wrote:

> On Mon, 06 Jul 2009 02:19:51 -0300, Gabriel Genellina wrote:
>
>> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
>> <steve at remove-this-cybersource.com.au> escribi?:
>>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>>
>>>> I wonder how many people have been tripped up by the fact that
>>>>
>>>>     ++n
>>>>
>>>> and
>>>>
>>>>     --n
>>>>
>>>> fail silently for numeric-valued n.
>>>
>>> What do you mean, "fail silently"? They do exactly what you should
>>> expect:
>>>>>> ++5  # positive of a positive number is positive
>>>
>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>> that are buggy, not Python.
>>
>> Well, those expectations are taken seriously when new features are
>> introduced into the language - and sometimes the feature is dismissed
>> just because it would be confusing for some. If a += 1 works, expecting
>> ++a to have the same meaning is very reasonable (for those coming from
>> languages with a ++ operator, like C or Java) - more when ++a is a
>> perfectly valid expression. If this issue isn't listed under the various
>> "Python gotchas" articles, it should...
>
> The fact that it isn't suggests strongly to me that it isn't that common
> a surprise even for Java and C programmers. This is the first time I've
> seen anyone raise it as an issue.

Indeed, arguably it's a bug for C compilers to fail to find the valid
parsing of "++5" as "+(+5)".  All I can say is that I've never even
accidentally typed that in twenty years of C programming.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From h.b.furuseth at usit.uio.no  Mon Jul  6 11:04:06 2009
From: h.b.furuseth at usit.uio.no (Hallvard B Furuseth)
Date: Mon, 06 Jul 2009 17:04:06 +0200
Subject: Help to find a regular expression to parse po file
References: <4A52084D.1010900@googlemail.com>
Message-ID: <hbf.20090706bevs@bombur.uio.no>

gialloporpora writes:
> I would like to extract string from a PO file. To do this I have created
> a little python function to parse po file and extract string:
>
> import re
> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
> m=r.findall(s)

I don't know the syntax of a po file, but this works for the
snippet you posted:

arg_re = r'"[^\\\"]*(?:\\.[^\\\"]*)*"'
arg_re = '%s(?:\s+%s)*' % (arg_re, arg_re)
find_re = re.compile(
    r'^msgid\s+(' + arg_re + ')\s*\nmsgstr\s+(' + arg_re + ')\s*\n', re.M)

However, can \ quote a newline? If so, replace \\. with \\[\s\S] or
something.
Can there be other keywords between msgid and msgstr?  If so,
add something like (?:\w+\s+<arg_re>\s*\n)*? between them.
Can msgstr come before msgid? If so, forget using a single regexp.
Anything else to the syntax to look out for?  Single quotes, maybe?

Is it a problem if the regexp isn't quite right and doesn't match all
cases, yet doesn't report an error when that happens?

All in all, it may be a bad idea to sqeeze this into a single regexp.
It gets ugly real fast.  Might be better to parse the file in a more
regular way, maybe using regexps just to extract each (keyword, "value")
pair.

-- 
Hallvard


From james at agentultra.com  Mon Jul  6 11:06:50 2009
From: james at agentultra.com (J Kenneth King)
Date: Mon, 06 Jul 2009 11:06:50 -0400
Subject: Code that ought to run fast, but can't due to Python limitations.
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
	<7xr5wvtqoh.fsf@ruckus.brouhaha.com>
	<mailman.2639.1246802753.8015.python-list@python.org>
	<h2qfl7$k87$1@panix3.panix.com>
Message-ID: <85prcdetpx.fsf@agentultra.com>

aahz at pythoncraft.com (Aahz) writes:

> In article <mailman.2639.1246802753.8015.python-list at python.org>,
> Hendrik van Rooyen <mail at microcorp.co.za> wrote:
>>
>>But wait - maybe if he passes an iterator around - the equivalent of
>>for char in input_stream...  Still no good though, unless the next call
>>to the iterator is faster than an ordinary python call.
>
> Calls to iterators created by generators are indeed faster than an
> ordinary Python call, because the stack frame is already mostly set up.

I think Beazely demonstrated this in his talk on using the python 2.5
co-routines to setup an xml parser.  I believe he benchmarked it roughly
and the initial results were rather impressive.

http://www.dabeaz.com/coroutines/


From python at mrabarnett.plus.com  Mon Jul  6 11:12:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 16:12:18 +0100
Subject: Help to find a regular expression to parse po file
In-Reply-To: <4A52084D.1010900@googlemail.com>
References: <4A52084D.1010900@googlemail.com>
Message-ID: <4A521452.4090405@mrabarnett.plus.com>

gialloporpora wrote:
> Hi all,
> I would like to extract string from a PO file. To do this I have created 
> a little python function to parse po file and extract string:
> 
> import re
> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
> m=r.findall(s)
> 
> where s is a po file like this:
> 
> msgctxt "write ubiquity commands.description"
> msgid "Takes you to the Ubiquity <a 
> href=\"chrome://ubiquity/content/editor.html\">command editor</a> page."
> msgstr "Apre l'<a href=\"chrome://ubiquity/content/editor.html\">editor 
> dei comandi</a> di Ubiquity."
> 
> 
> #. list ubiquity commands command:
> #. use | to separate multiple name values:
> msgctxt "list ubiquity commands.names"
> msgid "list ubiquity commands"
> msgstr "elenco comandi disponibili"
> 
> msgctxt "list ubiquity commands.description"
> msgid "Opens <a href=\"chrome://ubiquity/content/cmdlist.html\">the 
> list</a>\n"
> "      of all Ubiquity commands available and what they all do."
> msgstr "Apre una <a 
> href=\"chrome://ubiquity/content/cmdlist.html\">pagina</a>\n"
> "      in cui sono elencati tutti i comandi disponibili e per ognuno 
> viene spiegato in breve a cosa serve."
> 
> 
> 
> #. change ubiquity settings command:
> #. use | to separate multiple name values:
> msgctxt "change ubiquity settings.names"
> msgid "change ubiquity settings|change ubiquity preferences|change 
> ubiquity skin"
> msgstr "modifica impostazioni di ubiquity|modifica preferenze di 
> ubiquity|modifica tema di ubiquity"
> 
> msgctxt "change ubiquity settings.description"
> msgid "Takes you to the <a 
> href=\"chrome://ubiquity/content/settings.html\">settings</a> page,\n"
> "      where you can change your skin, key combinations, etc."
> msgstr "Apre la pagina  <a 
> href=\"chrome://ubiquity/content/settings.html\">delle impostazioni</a> 
> di Ubiquity,\n"
> "     dalla quale ?? possibile modificare la combinazione da tastiera 
> utilizzata per richiamare Ubiquity, il tema, ecc."
> 
> 
> 
> but, obviusly,  with the code above the  last string is not matched. If 
> I use re.DOTALL to match also new line character it not works because it 
> match the entire file, I would like to stop the matching when "msgstr" 
> is found.
> 
> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n\\n",re.DOTALL)
> 
> is it possible or not ?
> 
You could try:

regex = re.compile(r"msgid (.*(?:\n".*")*)\nmsgstr (.*(?:\n".*")*)$")

and then, if necessary, tidy what you get.


From pm567426 at gmail.com  Mon Jul  6 11:13:00 2009
From: pm567426 at gmail.com (Pedram)
Date: Mon, 6 Jul 2009 08:13:00 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com> 
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com>
Message-ID: <173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com>

Hello Mr. Dickinson. Glad to see you again :)

On Jul 6, 5:46?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
>
> > OK, fine, I read longobject.c at last! :)
> > I found that longobject is a structure like this:
>
> > struct _longobject {
> > ? ? struct _object *_ob_next;
> > ? ? struct _object *_ob_prev;
>
> For current CPython, these two fields are only present in debug
> builds; ?for a normal build they won't exist.

I couldn't understand the difference between them. What are debug
build and normal build themselves? And You mean in debug build
PyLongObject is a doubly-linked-list but in normal build it is just an
array (Or if not how it'll store in this mode)?

> > ? ? Py_ssize_t ob_refcnt;
> > ? ? struct _typeobject *ob_type;
>
> You're missing an important field here (see the definition of
> PyObject_VAR_HEAD):
>
> ? ? Py_ssize_t ob_size; /* Number of items in variable part */
>
> For the current implementation of Python longs, the absolute value of
> this field gives the number of digits in the long; ?the sign gives the
> sign of the long (0L is represented with zero digits).

Oh, you're right. I missed that. Thanks :)

> > ? ? digit ob_digit[1];
>
> Right. ?This is an example of the so-called 'struct hack' in C; it
> looks as though there's just a single digit, but what's intended here
> is that there's an array of digits tacked onto the end of the struct;
> for any given PyLongObject, the size of this array is determined at
> runtime. ?(C99 allows you to write this as simply ob_digit[], but not
> all compilers support this yet.)

WOW! I didn't know anything about 'struct hacks'! I read about them
and they were very wonderful. Thanks for your point. :)

> > }
> > And a digit is a 15-item array of C's unsigned short integers.
>
> No: a digit is a single unsigned short, which is used to store 15 bits
> of the Python long. ?Python longs are stored in sign-magnitude format,
> in base 2**15. ?So each of the base 2**15 'digits' is an integer in
> the range [0, 32767). ?The unsigned short type is used to store those
> digits.
>
> Exception: for Python 2.7+ or Python 3.1+, on 64-bit machines, Python
> longs are stored in base 2**30 instead of base 2**15, using a 32-bit
> unsigned integer type in place of unsigned short.
>
> > Is this structure is constant in
> > all environments (Linux, Windows, Mobiles, etc.)?
>
> I think it would be dangerous to rely on this struct staying constant,
> even just for CPython. ?It's entirely possible that the representation
> of Python longs could change in Python 2.8 or 3.2. ?You should use the
> public, documented C-API whenever possible.
>
> Mark

Thank you a lot Mark :)


From piet at cs.uu.nl  Mon Jul  6 11:15:47 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 06 Jul 2009 17:15:47 +0200
Subject: Why is my code faster with append() in a loop than with a large
	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
Message-ID: <m2r5wtetb0.fsf@cs.uu.nl>

>>>>> Dave Angel <davea at dejaviewphoto.com> (DA) wrote:

>DA> It would probably save some time to not bother storing the zeroes in the
>DA> list at all.  And it should help if you were to step through a list of
>DA> primes, rather than trying every possible int.  Or at least constrain
>DA> yourself to odd numbers (after the initial case of 2).

The first and the last save a constant factor (slightly less than 2):

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    factor = 2
    while num > 1:
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            powers.append(power+1)
        factor += 1
    return powers

...
    return reduce(mul, powers)

or to skip the odd factors:

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    factor = 2
    while num > 1:
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            powers.append(power+1)
        factor = 3 if factor == 2 else factor + 2
    return powers

This can be slightly optimised by taking factor 2 out of the loop.

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    power = 0
    while num % 2 == 0:
        power += 1
        num /= 2
    if power > 0:
        powers.append(power+1)
    factor = 3
    while num > 1:
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            powers.append(power+1)
        factor += 2
    return powers

To restrict the search to primes you would have to use a
sieve of Eratosthenes or something similar.
My first attempt (with a sieve from
http://code.activestate.com/recipes/117119/) only gave a speed decrease!!
But this had the sieve recreated for every triangle number. A global
sieve that is reused at each triangle number is better. But the speed
increase relative to the odd factors only is not dramatical.


# Based upon http://code.activestate.com/recipes/117119/

D = {9: 6} # contains composite numbers
Dlist = [2, 3] # list of already generated primes

def sieve():
    '''generator that yields all prime numbers'''
    global D
    global Dlist
    for p in Dlist:
        yield p
    q = Dlist[-1]+2
    while True:
        if q in D:
            p = D[q]
            x = q + p
            while x in D: x += p
            D[x] = p
        else:
            Dlist.append(q)
            yield q
            D[q*q] = 2*q
        q += 2

def factorise(num):
    """Returns a list of prime factor powers. For example:
        factorise(6) will return
        [2, 2] (the powers are returned one higher than the actual value)
        as in, 2^1 * 3^1 = 6."""
    powers = []
    power = 0
    for factor in sieve():
        power = 0
        while num % factor == 0:
            power += 1
            num /= factor
        if power > 0:
            # if you really want the factors then append((factor, power))
            powers.append(power+1)
        if num == 1:
            break
    return powers

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rhodri at wildebst.demon.co.uk  Mon Jul  6 11:22:43 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Mon, 06 Jul 2009 16:22:43 +0100
Subject: Python and webcam capture delay?
In-Reply-To: <czg4m.20786$vi5.9666@uutiset.elisa.fi>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
Message-ID: <op.uwnjn5ija8ncjz@gnudebst>

On Mon, 06 Jul 2009 07:10:38 +0100, jack catcher (nick) <nomail at thank.you>  
wrote:

> Tim Roberts kirjoitti:
>> "jack catcher (nick)" <nomail at thank.you> wrote:
>>> I'm thinking of using Python for capturing and showing live webcam  
>>> stream simultaneously between two computers via local area network.  
>>> Operating system is Windows. I'm going to begin with VideoCapture  
>>> extension, no ideas about other implementation yet. Do you have any  
>>> suggestions on how short delay I should hope to achieve in showing the  
>>> video? This would be part of a psychological experiment, so I would  
>>> need to deliver the video stream with a reasonable delay (say, below  
>>> 100ms).
>>  You need to do the math on this.  Remember that a full 640x480 RGB  
>> stream
>> at 30 frames per second runs 28 megabytes per second.  That's more than
>> twice what a 100 megabit network can pump.
>>  You can probably use Python to oversee this, but you might want to  
>> consider
>> using lower-level code to control the actual hardware.  If you are
>> targeting Windows, for example, you could write a DirectShow graph to  
>> pump
>> into a renderer that transmits out to a network, then another graph to
>> receive from the network and display it.
>>  You can manage the network latency by adding a delays in the local  
>> graph.
>
> Thanks Tim, you're correct about the math. What is your main point about  
> DirectShow: that it is generally faster and more reliable than doing the  
> job high-level, or that one could use coding/decoding in DirectShow to  
> speed up the transmission? I think the latter would be a great idea if  
> the latency were tolerable. On the other hand, I'd like to keep things  
> simple and do all the programming in Python. I've got no experience with  
> DirectShow, but I guess the filters need to be programmed in C++ and  
> called from Python?
>
> Another option might be to use resolution 320x240 at 15fps.

Does the webcam just deliver frames, or are you getting frames out of
a decoder layer?  If it's the latter, you want to distribute the encoded
video, which should be much lower bandwidth.  Exactly how you do that
depends a bit on what format the webcam claims to deliver.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From jeanmichel at sequans.com  Mon Jul  6 11:24:53 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 06 Jul 2009 17:24:53 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <000901c9fe42$b026cfc0$0d00a8c0@Hendrik>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>
	<006201c9fd48$666d94e0$0d00a8c0@Hendrik>
	<4A51F3EB.1080509@sequans.com>
	<000901c9fe42$b026cfc0$0d00a8c0@Hendrik>
Message-ID: <4A521745.8040307@sequans.com>

Hendrik van Rooyen wrote:
> "Jean-Michel Pichavant" <jeanmichel at s....ns.com> wrote:
>
>   
>> Woot ! I'll keep this one in my mind, while I may not be that concerned 
>> by speed unlike the OP, I still find this way of doing very simple and 
>> so intuitive (one will successfully argue how I was not figuring this 
>> out by myself if it was so intuitive).
>> Anyway I wanted to participated to this thread, as soon as I saw 'due to 
>> python limitations' in the title, I foretold a hell of a thread ! This 
>> is just provocation ! :-)
>>     
>
> The OP was not being provocative - he has a real problem, 

I was just kidding, asserting for python limitations in this list 
guarantees that the thread will last for several days, whether or not 
the assertion is right.

JM


From python-url at phaseit.net  Mon Jul  6 11:33:47 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Mon, 6 Jul 2009 15:33:47 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul  6)
Message-ID: <h2t5gr$9mt$1@lairds.us>

QOTW:  "Simulating a shell with hooks on its I/O should be so complicated that
a 'script kiddie' has trouble writing a Trojan." - Scott David Daniels
    http://groups.google.com/group/comp.lang.python/msg/1c0f70d5fc69b5aa
    
    
    Python 3.1 final was released last week - congratulations!
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b37a041ce01d4168/
    
    Clarity of code vs. reusability in an introductory course:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b1a6ca84d3bfc483/
    
    A piece of code analyzed, looking for ways to improve speed:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/a420417a1e215cf0/
    
    Beginner question: How to define an indeterminate number of variables?
    How to create objects, and later reference them, when one doesn't know
    how many of them will be needed?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/c40e3c0c843ce6fb/
    
    Simple things made simple: correct use of Unicode helps a lot in this case:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/9cbb01aacf23fa8f/
    
    super() and multiple inheritance: __init__ is hard to get right. Also,
    Carl Banks explains how mixin classes are best used:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/c934715ac83dfbd/
    
    iter(function, sentinel) is a handy way to iterate in some cases, but
    beware of the fine print:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b977c3b39abd98b0
    
    The testing code should not merely repeat the code being tested (this
    fact isn't obvious to everyone):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8978c54b83f80bd6/
    
    Organize code so it can be run both in the source tree and after being
    installed:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/62284434d2ca5e1f/
    
    Mark Dickinson explains the C implementation of long integers:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/aa1d06d371658135/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From digitig at gmail.com  Mon Jul  6 11:43:43 2009
From: digitig at gmail.com (Tim Rowe)
Date: Mon, 6 Jul 2009 16:43:43 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2ogli$n9p$2@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
Message-ID: <aee48b3c0907060843y2635c531ydd27403a5c032c4e@mail.gmail.com>

2009/7/4 kj <no.email at please.post>:

> Precisely. ?As I've stated elsewhere, this is an internal helper
> function, to be called only a few times under very well-specified
> conditions. ?The assert statements checks that these conditions
> are as intended. ?I.e. they are checks against the module writer's
> programming errors.

Good for you. I'm convinced that you have used the assertion
appropriately, and the fact that so many here are unable to see that
looks to me like a good case for teaching the right use of assertions.
For what it's worth, I read assertions at the beginning of a procedure
as part of the specification of the procedure, and I use them there in
order to document the procedure. An assertion in that position is for
me a statement to the user of the procedure "it's your responsibility
to make sure that you never call this procedure in such a way as to
violate these conditions". They're part of a contract, as somebody
(maybe you) pointed out.

As somebody who works in the safety-critical domain, it's refreshing
to see somebody teaching students to think about the circumstances in
which a procedure can legitimately be called. The hostility you've
received to that idea is saddening, and indicative of why there's so
much buggy software out there.
-- 
Tim Rowe


From dmhouse at gmail.com  Mon Jul  6 11:46:45 2009
From: dmhouse at gmail.com (David House)
Date: Mon, 6 Jul 2009 16:46:45 +0100
Subject: try -> except -> else -> except?
Message-ID: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>

Hi all,

I'm looking for some structure advice. I'm writing something that
currently looks like the following:

try:
    <short amount of code that may raise a KeyError>
except KeyError:
    <error handler>
else:
    <nontrivial amount of code>

This is working fine. However, I now want to add a call to a function
in the `else' part that may raise an exception, say a ValueError. So I
was hoping to do something like the following:

try:
    <short amount of code that may raise a KeyError>
except KeyError:
    <error handler>
else:
    <nontrivial amount of code>
except ValueError:
    <error handler>

However, this isn't allowed in Python.

An obvious way round this is to move the `else' clause into the `try', i.e.,

try:
    <short amount of code that may raise a KeyError>
    <nontrivial amount of code>
except KeyError:
    <error handler>
except ValueError:
    <error handler>

However, I am loath to do this, for two reasons:

(i) if I modify the <nontrivial amount of code> block at some point in
the future so that it may raise a KeyError, I have to somehow tell
this exception from the one that may be generated from the <short
amount of code that may raise a KeyError> line.
(ii) it moves the error handler for the <short amount of code that may
raise a KeyError> bit miles away from the line that might generate the
error, making it unclear which code the KeyError error handler is an
error handler for.

What would be the best way to structure this?

-- 
-David


From piet at cs.uu.nl  Mon Jul  6 11:51:02 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 06 Jul 2009 17:51:02 +0200
Subject: Why is my code faster with append() in a loop than with a large
	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
	<m2r5wtetb0.fsf@cs.uu.nl>
Message-ID: <m2my7hero9.fsf@cs.uu.nl>

Sorry, there was an error in the sieve in my last example. Here is a
corrected version:

D = {9: 6} # contains composite numbers
Dlist = [2, 3] # list of already generated primes
def sieve():
    '''generator that yields all prime numbers'''
    global D
    global Dlist
    for q in Dlist:
        yield q
    while True:
        q += 2
        p = D.pop(q, 0)
        if p:
            x = q + p
            while x in D: x += p
            D[x] = p
        else:
            Dlist.append(q)
            D[q*q] = 2*q
            yield q

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul  6 11:56:21 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 06 Jul 2009 17:56:21 +0200
Subject: try -> except -> else -> except?
References: <mailman.2701.1246895207.8015.python-list@python.org>
Message-ID: <m2iqi5erfe.fsf@cs.uu.nl>

>>>>> David House <dmhouse at gmail.com> (DH) wrote:

>DH> Hi all,
>DH> I'm looking for some structure advice. I'm writing something that
>DH> currently looks like the following:

>DH> try:
>DH>     <short amount of code that may raise a KeyError>
>DH> except KeyError:
>DH>     <error handler>
>DH> else:
>DH>     <nontrivial amount of code>

>DH> This is working fine. However, I now want to add a call to a function
>DH> in the `else' part that may raise an exception, say a ValueError. So I
>DH> was hoping to do something like the following:

>DH> try:
>DH>     <short amount of code that may raise a KeyError>
>DH> except KeyError:
>DH>     <error handler>
>DH> else:
>DH>     <nontrivial amount of code>
>DH> except ValueError:
>DH>     <error handler>

>DH> However, this isn't allowed in Python.

>DH> An obvious way round this is to move the `else' clause into the `try', i.e.,

>DH> try:
>DH>     <short amount of code that may raise a KeyError>
>DH>     <nontrivial amount of code>
>DH> except KeyError:
>DH>     <error handler>
>DH> except ValueError:
>DH>     <error handler>

>DH> However, I am loath to do this, for two reasons:

>DH> (i) if I modify the <nontrivial amount of code> block at some point in
>DH> the future so that it may raise a KeyError, I have to somehow tell
>DH> this exception from the one that may be generated from the <short
>DH> amount of code that may raise a KeyError> line.
>DH> (ii) it moves the error handler for the <short amount of code that may
>DH> raise a KeyError> bit miles away from the line that might generate the
>DH> error, making it unclear which code the KeyError error handler is an
>DH> error handler for.

>DH> What would be the best way to structure this?

try:
    <short amount of code that may raise a KeyError>
except KeyError:
    <error handler>
else:
    try:
        <nontrivial amount of code>
    except ValueError:
        <error handler>

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at rgbaz.eu  Mon Jul  6 12:02:18 2009
From: python at rgbaz.eu (Python)
Date: Mon, 6 Jul 2009 18:02:18 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
Message-ID: <DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>


On 6 jul 2009, at 17:46, David House wrote:

> Hi all,
>
> I'm looking for some structure advice. I'm writing something that
> currently looks like the following:
>
> try:
>    <short amount of code that may raise a KeyError>
> except KeyError:
>    <error handler>
> else:
>    <nontrivial amount of code>
>
> This is working fine. However, I now want to add a call to a function
> in the `else' part that may raise an exception, say a ValueError. So I
> was hoping to do something like the following:
>
> try:
>    <short amount of code that may raise a KeyError>
> except KeyError:
>    <error handler>
> else:
>    <nontrivial amount of code>
> except ValueError:
>    <error handler>
>
> However, this isn't allowed in Python.
>
> An obvious way round this is to move the `else' clause into the  
> `try', i.e.,
>
> try:
>    <short amount of code that may raise a KeyError>
>    <nontrivial amount of code>
> except KeyError:
>    <error handler>
> except ValueError:
>    <error handler>
>
> However, I am loath to do this, for two reasons:
>
> (i) if I modify the <nontrivial amount of code> block at some point in
> the future so that it may raise a KeyError, I have to somehow tell
> this exception from the one that may be generated from the <short
> amount of code that may raise a KeyError> line.
> (ii) it moves the error handler for the <short amount of code that may
> raise a KeyError> bit miles away from the line that might generate the
> error, making it unclear which code the KeyError error handler is an
> error handler for.
>
> What would be the best way to structure this?
>
> -- 
> -David
>

as far as I know try has no 'else'
it's 'finally'

try:
	a
except:
	b
except:
	c
finally:
	d

gr
Arno



From deets at nospam.web.de  Mon Jul  6 12:10:36 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 06 Jul 2009 18:10:36 +0200
Subject: How to map size_t using ctypes?
References: <mailman.2691.1246888326.8015.python-list@python.org>
Message-ID: <7belo1F21fs3vU1@mid.uni-berlin.de>

Philip Semanchuk wrote:

> Hi all,
> I can't figure out how to map a C variable of size_t via Python's
> ctypes module. Let's say I have a C function like this:
> 
> void populate_big_array(double *the_array, size_t element_count) {...}
> 
> How would I pass parameter 2? A long (or ulong) will (probably) work
> (on most platforms), but I like my code to be more robust than that.
> Furthermore, this is scientific code and it's entirely possible that
> someone will want to pass a huge array with more elements than can be
> described by a 32-bit long.

from ctypes import c_size_t

doesn't work for you? On my system, it's aliased to c_ulong, but I guess
that's depending on the platfrom of course.

Diez


From dmhouse at gmail.com  Mon Jul  6 12:14:23 2009
From: dmhouse at gmail.com (David House)
Date: Mon, 6 Jul 2009 17:14:23 +0100
Subject: try -> except -> else -> except?
In-Reply-To: <DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
	<DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>
Message-ID: <ebe43d680907060914o6e4d859qd90a768f4f52bc88@mail.gmail.com>

2009/7/6 Python <python at rgbaz.eu>:
> as far as I know try has no 'else'

It does:
http://docs.python.org/reference/compound_stmts.html#the-try-statement

> it's 'finally'

There is a `finally', too, but they are semantically different. See
the above link.

-- 
-David


From python at rgbaz.eu  Mon Jul  6 12:17:24 2009
From: python at rgbaz.eu (Python)
Date: Mon, 6 Jul 2009 18:17:24 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <ebe43d680907060914o6e4d859qd90a768f4f52bc88@mail.gmail.com>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
	<DA70CB42-5E42-4A7B-A042-1687D641AA57@rgbaz.eu>
	<ebe43d680907060914o6e4d859qd90a768f4f52bc88@mail.gmail.com>
Message-ID: <1661ED1F-8AC9-48A7-8C87-0090942664B1@rgbaz.eu>


On 6 jul 2009, at 18:14, David House wrote:

> 2009/7/6 Python <python at rgbaz.eu>:
>> as far as I know try has no 'else'
>
> It does:
> http://docs.python.org/reference/compound_stmts.html#the-try-statement
>
>> it's 'finally'
>
> There is a `finally', too, but they are semantically different. See
> the above link.
>
> -- 
> -David
>
>
ah yeah you;re right, sry

shouldn't the else statement come after the except ones maybe?


From usernet at ilthio.net  Mon Jul  6 12:25:33 2009
From: usernet at ilthio.net (Tim Harig)
Date: Mon, 06 Jul 2009 16:25:33 GMT
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
	<d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
Message-ID: <1Ap4m.2113$8r.633@nlpi064.nbdc.sbc.com>

On 2009-07-06, RAM <serverin2000 at yahoo.com> wrote:
> I am trying to do this on windows. My program(executable) has been
> written in VC++ and when I run this program, I need to click on one
> button on the program GUI i,e just I am entering "Enter key" on the
> key board. But this needs manual process. So i need to write a python
> script which invokes my program and pass "Enter key" event to my
> program so that it runs without manual intervention.

This can be done using the WScript.WshShell.SendKeys() method when running
Python with Windows Scripting Host by using the .pyw extension:

http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx


From philip at semanchuk.com  Mon Jul  6 12:29:21 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 12:29:21 -0400
Subject: How to map size_t using ctypes?
In-Reply-To: <7belo1F21fs3vU1@mid.uni-berlin.de>
References: <mailman.2691.1246888326.8015.python-list@python.org>
	<7belo1F21fs3vU1@mid.uni-berlin.de>
Message-ID: <DB4ED723-C8DD-492F-A7CC-B3CE14F8B723@semanchuk.com>


On Jul 6, 2009, at 12:10 PM, Diez B. Roggisch wrote:

> Philip Semanchuk wrote:
>
>> Hi all,
>> I can't figure out how to map a C variable of size_t via Python's
>> ctypes module. Let's say I have a C function like this:
>>
>> void populate_big_array(double *the_array, size_t element_count)  
>> {...}
>>
>> How would I pass parameter 2? A long (or ulong) will (probably) work
>> (on most platforms), but I like my code to be more robust than that.
>> Furthermore, this is scientific code and it's entirely possible that
>> someone will want to pass a huge array with more elements than can be
>> described by a 32-bit long.
>
> from ctypes import c_size_t
>
> doesn't work for you? On my system, it's aliased to c_ulong, but I  
> guess
> that's depending on the platfrom of course.

D'oh! [slaps forehead]

That will teach me to RTFM. In my 2.5 doc, it's not listed in the  
"Fundamental data types" section in the tutorial, but it is mentioned  
in "Fundamental data types" in the ctypes reference. You'd be  
surprised at the amount of Googling I did without learning this on my  
own.

Thanks
Philip


From "sandrodll[remove]" at googlemail.com  Mon Jul  6 12:32:47 2009
From: "sandrodll[remove]" at googlemail.com (gialloporpora)
Date: Mon, 06 Jul 2009 18:32:47 +0200
Subject: Help to find a regular expression to parse po file
In-Reply-To: <hbf.20090706bevs@bombur.uio.no>
References: <4A52084D.1010900@googlemail.com> <hbf.20090706bevs@bombur.uio.no>
Message-ID: <4A52272F.10209@googlemail.com>

Risposta al messaggio di Hallvard B Furuseth :


>
> I don't know the syntax of a po file, but this works for the
> snippet you posted:
>
> arg_re = r'"[^\\\"]*(?:\\.[^\\\"]*)*"'
> arg_re = '%s(?:\s+%s)*' % (arg_re, arg_re)
> find_re = re.compile(
>      r'^msgid\s+(' + arg_re + ')\s*\nmsgstr\s+(' + arg_re + ')\s*\n', re.M)
>
> However, can \ quote a newline? If so, replace \\. with \\[\s\S] or
> something.
> Can there be other keywords between msgid and msgstr?  If so,
> add something like (?:\w+\s+<arg_re>\s*\n)*? between them.
> Can msgstr come before msgid? If so, forget using a single regexp.
> Anything else to the syntax to look out for?  Single quotes, maybe?
>
> Is it a problem if the regexp isn't quite right and doesn't match all
> cases, yet doesn't report an error when that happens?
>
> All in all, it may be a bad idea to sqeeze this into a single regexp.
> It gets ugly real fast.  Might be better to parse the file in a more
> regular way, maybe using regexps just to extract each (keyword, "value")
> pair.
>
Thank you very much, Haldvard, it seem to works, there is a strange 
match in the file header but I could skip the first match.


The po files have this structure:
http://bit.ly/18qbVc

msgid "string to translate"
"   second string to match"
"   n string to match"
msgstr "translated sting"
"   second translated string"
"  n translated string"
One or more new line before the next group.

In past I have created a Python script to parse PO files  where msgid 
and msgstr are in two sequential lines, for example:

msgid "string to translate"
msgstr "translated string"

now the problem is how to match also (optional) string between msgid and 
msgstr.

Sandro







From davea at ieee.org  Mon Jul  6 12:49:49 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 12:49:49 -0400
Subject: Why is my code faster with append() in a loop than with a
	large	list?
In-Reply-To: <4A52089F.7020301@mrabarnett.plus.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<4A51CD6A.2010106@dejaviewphoto.com>
	<4A52089F.7020301@mrabarnett.plus.com>
Message-ID: <4A522B2D.60407@ieee.org>

MRAB wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
> [snip]
>> It would probably save some time to not bother storing the zeroes in 
>> the list at all.  And it should help if you were to step through a 
>> list of primes, rather than trying every possible int.  Or at least 
>> constrain yourself to odd numbers (after the initial case of 2).
>>
> Or stop looking for more factors when you've passed the square root of
> num. I don't know what effect there'll be on the time if you recalculate
> the square root when num changes (expensive calculation vs smaller
> search space).
>
> </div>
>
But if I remember the code, it stopped when the quotient is one, which 
is usually sooner than the square root.  And no need to precalculate the 
square root.



From Scott.Daniels at Acm.Org  Mon Jul  6 12:53:34 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 09:53:34 -0700
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <m2r5wtetb0.fsf@cs.uu.nl>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
	<m2r5wtetb0.fsf@cs.uu.nl>
Message-ID: <U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>

Piet van Oostrum wrote:
>>>>>> Dave Angel <davea at dejaviewphoto.com> (DA) wrote:
> 
>> DA> It would probably save some time to not bother storing the zeroes in the
>> DA> list at all.  And it should help if you were to step through a list of
>> DA> primes, rather than trying every possible int.  Or at least constrain
>> DA> yourself to odd numbers (after the initial case of 2).
> 
> ...
> # Based upon http://code.activestate.com/recipes/117119/
> 
> D = {9: 6} # contains composite numbers
XXX Dlist = [2, 3] # list of already generated primes
   Elist = [(2, 4), (3, 9)] # list of primes and their squares
> 
XXX def sieve():
XXX   '''generator that yields all prime numbers'''
XXX   global D
XXX   global Dlist
  def sieve2():
      '''generator that yields all primes and their squares'''
      # No need for global declarations, we alter, not replace
XXX   for p in Dlist:
XXX       yield p
XXX   q = Dlist[-1]+2

       for pair in Elist:
           yield pair
       q = pair[0] + 2

>     while True:
>         if q in D:
>             p = D[q]
>             x = q + p
>             while x in D: x += p
>             D[x] = p
>         else:
XXX           Dlist.append(q)
XXX           yield q
XXX           D[q*q] = 2*q
               square = q * q
               pair = q, square
               Elist.append(pair)
               yield pair
               D[square] = 2 * q
>         q += 2
> 
> def factorise(num):
>     """Returns a list of prime factor powers. For example:
>         factorise(6) will return
>         [2, 2] (the powers are returned one higher than the actual value)
>         as in, 2^1 * 3^1 = 6."""
>     powers = []
>     power = 0
XXX   for factor in sieve():
       for factor, limit in sieve2():
>         power = 0
>         while num % factor == 0:
>             power += 1
>             num /= factor
XXX       if power > 0:
           if power: # good enough here, and faster
>             # if you really want the factors then append((factor, power))
>             powers.append(power+1)
XXX       if num == 1:
XXX           break
XXX   return powers
           if num < limit:
               if num > 1:
                   # if you really want the factors then append((num, 1))
                   powers.append(2)
               return powers

OK, that's a straightforward speedup, _but_:
      factorize(6) == [2, 2] == factorize(10) ==  factorize(15)
So I am not sure exactly what you are calculating.


--Scott David Daniels
Scott.Daniels at Acm.Org


From davea at ieee.org  Mon Jul  6 12:54:35 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 12:54:35 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <op.uwninxtza8ncjz@gnudebst>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<op.uwninxtza8ncjz@gnudebst>
Message-ID: <4A522C4B.20102@ieee.org>

Rhodri James wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">On Mon, 
> 06 Jul 2009 10:58:21 +0100, Steven D'Aprano 
> <steve at remove-this-cybersource.com.au> wrote:
>
>> On Mon, 06 Jul 2009 02:19:51 -0300, Gabriel Genellina wrote:
>>
>>> En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
>>> <steve at remove-this-cybersource.com.au> escribi?:
>>>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>>>
>>>>> I wonder how many people have been tripped up by the fact that
>>>>>
>>>>>     ++n
>>>>>
>>>>> and
>>>>>
>>>>>     --n
>>>>>
>>>>> fail silently for numeric-valued n.
>>>>
>>>> What do you mean, "fail silently"? They do exactly what you should
>>>> expect:
>>>>>>> ++5  # positive of a positive number is positive
>>>>
>>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>>> that are buggy, not Python.
>>>
>>> Well, those expectations are taken seriously when new features are
>>> introduced into the language - and sometimes the feature is dismissed
>>> just because it would be confusing for some. If a += 1 works, expecting
>>> ++a to have the same meaning is very reasonable (for those coming from
>>> languages with a ++ operator, like C or Java) - more when ++a is a
>>> perfectly valid expression. If this issue isn't listed under the 
>>> various
>>> "Python gotchas" articles, it should...
>>
>> The fact that it isn't suggests strongly to me that it isn't that common
>> a surprise even for Java and C programmers. This is the first time I've
>> seen anyone raise it as an issue.
>
> Indeed, arguably it's a bug for C compilers to fail to find the valid
> parsing of "++5" as "+(+5)".  All I can say is that I've never even
> accidentally typed that in twenty years of C programming.
>
But the C language specifically defines the tokenizer as doing a 
max-match, finding the longest legal token at any point.  That's how 
many things that would otherwise be ambiguous are well-defined.  For 
example, if you want to divide two integers, given pointers to them, you 
need a space between the slash and the start.
         *p1/*p2    begins a comment,  while   *p1/ *p2   does a division




From davea at ieee.org  Mon Jul  6 13:13:48 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 13:13:48 -0400
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<mailman.2683.1246875006.8015.python-list@python.org>	<m2r5wtetb0.fsf@cs.uu.nl>
	<U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>
Message-ID: <4A5230CC.2020801@ieee.org>

Scott David Daniels wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Piet van 
> Oostrum wrote:
>>>>>>> Dave Angel <davea at dejaviewphoto.com> (DA) wrote:
>>
>>> DA> It would probably save some time to not bother storing the 
>>> zeroes in the
>>> DA> list at all.  And it should help if you were to step through a 
>>> list of
>>> DA> primes, rather than trying every possible int.  Or at least 
>>> constrain
>>> DA> yourself to odd numbers (after the initial case of 2).
>>
>> ...
>> # Based upon http://code.activestate.com/recipes/117119/
>>
>> D = {9: 6} # contains composite numbers
> XXX Dlist = [2, 3] # list of already generated primes
>   Elist = [(2, 4), (3, 9)] # list of primes and their squares
>>
> XXX def sieve():
> XXX   '''generator that yields all prime numbers'''
> XXX   global D
> XXX   global Dlist
>  def sieve2():
>      '''generator that yields all primes and their squares'''
>      # No need for global declarations, we alter, not replace
> XXX   for p in Dlist:
> XXX       yield p
> XXX   q = Dlist[-1]+2
>
>       for pair in Elist:
>           yield pair
>       q = pair[0] + 2
>
>>     while True:
>>         if q in D:
>>             p = D[q]
>>             x = q + p
>>             while x in D: x += p
>>             D[x] = p
>>         else:
> XXX           Dlist.append(q)
> XXX           yield q
> XXX           D[q*q] = 2*q
>               square = q * q
>               pair = q, square
>               Elist.append(pair)
>               yield pair
>               D[square] = 2 * q
>>         q += 2
>>
>> def factorise(num):
>>     """Returns a list of prime factor powers. For example:
>>         factorise(6) will return
>>         [2, 2] (the powers are returned one higher than the actual 
>> value)
>>         as in, 2^1 * 3^1 = 6."""
>>     powers = []
>>     power = 0
> XXX   for factor in sieve():
>       for factor, limit in sieve2():
>>         power = 0
>>         while num % factor == 0:
>>             power += 1
>>             num /= factor
> XXX       if power > 0:
>           if power: # good enough here, and faster
>>             # if you really want the factors then append((factor, 
>> power))
>>             powers.append(power+1)
> XXX       if num == 1:
> XXX           break
> XXX   return powers
>           if num < limit:
>               if num > 1:
>                   # if you really want the factors then append((num, 1))
>                   powers.append(2)
>               return powers
>
> OK, that's a straightforward speedup, _but_:
>      factorize(6) == [2, 2] == factorize(10) ==  factorize(15)
> So I am not sure exactly what you are calculating.
>
>
> --Scott David Daniels
> Scott.Daniels at Acm.Org
>
> </div>
>
The OP only needed the number of factors, not the actual factors.  So 
the zeroes in the list are unneeded.  6, 10, and 15 each have 4 factors.




From sajmikins at gmail.com  Mon Jul  6 13:15:22 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Mon, 6 Jul 2009 13:15:22 -0400
Subject: Tree structure consuming lot of memory
In-Reply-To: <ff4d16090907060312n6df077capcce97ddd0786983@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<50697b2c0907060303r6bad875dr1eb1ab2482f54e03@mail.gmail.com>
	<ff4d16090907060312n6df077capcce97ddd0786983@mail.gmail.com>
Message-ID: <50f98a4c0907061015n68191f9bj868b8e1b8908223c@mail.gmail.com>

On Mon, Jul 6, 2009 at 6:12 AM, mayank gupta<mooniitk at gmail.com> wrote:
> Thanks for the other possibilites. I would consider option (2) and (3) to
> improve my code.
>
> But out of curiosity, I would still like to know why does an object of a
> Python-class consume "so" much of memory (1.4 kb), and this memory usage has
> nothing to do with its attributes.
>
> Thanks
>
> Regards.
>
> On Mon, Jul 6, 2009 at 12:03 PM, Chris Rebert <clp2 at rebertia.com> wrote:
>>
>> On Mon, Jul 6, 2009 at 2:55 AM, mayank gupta<mooniitk at gmail.com> wrote:
>> > Hi,
>> >
>> > I am creating a tree data-structure in python; with nodes of the tree
>> > created by a simple class :
>> >
>> > class Node :
>> > ?????? def __init__(self , .... other attributes):
>> > ????????????? # initialise the attributes here!!
>> >
>> > But the problem is I am working with a huge tree (millions of nodes);
>> > and
>> > each node is consuming much more memory than it should. After a little
>> > analysis, I found out that in general it uses about 1.4 kb of memory for
>> > each node!!
>> > I will be grateful if someone could help me optimize the memory usage.
>>
>> (1) Use __slots__ (see
>> http://docs.python.org/reference/datamodel.html#slots)
>> (2) Use some data structure other than a tree
>> (3) Rewrite your Node/Tree implementation in C
>>
>> Cheers,
>> Chris
>> --
>> http://blog.rebertia.com
>

For option 2 you should try using the built in types, list tuple or
dict.  You might get better results.

I'm curious too as to why the class/instance code should take so much
memory, could you mention more about the code?


From python at mrabarnett.plus.com  Mon Jul  6 13:20:59 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 18:20:59 +0100
Subject: Why is my code faster with append() in a loop than with a large
	list?
In-Reply-To: <4A522B2D.60407@ieee.org>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<4A51CD6A.2010106@dejaviewphoto.com>
	<4A52089F.7020301@mrabarnett.plus.com> <4A522B2D.60407@ieee.org>
Message-ID: <4A52327B.3000403@mrabarnett.plus.com>

Dave Angel wrote:
> MRAB wrote:
>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
>> Angel wrote:
>> [snip]
>>> It would probably save some time to not bother storing the zeroes in 
>>> the list at all.  And it should help if you were to step through a 
>>> list of primes, rather than trying every possible int.  Or at least 
>>> constrain yourself to odd numbers (after the initial case of 2).
>>>
>> Or stop looking for more factors when you've passed the square root of
>> num. I don't know what effect there'll be on the time if you recalculate
>> the square root when num changes (expensive calculation vs smaller
>> search space).
>>
>> </div>
>>
> But if I remember the code, it stopped when the quotient is one, which 
> is usually sooner than the square root.  And no need to precalculate the 
> square root.
> 
If the number is a large prime then the code will try all the numbers up
to that, eg if num == 1000003 then it'll try 2..1000003 even though it
could've given up after 1000.


From pescadero10 at gmail.com  Mon Jul  6 13:30:41 2009
From: pescadero10 at gmail.com (pescadero10)
Date: Mon, 6 Jul 2009 10:30:41 -0700 (PDT)
Subject: updating, adding new pages to confluence remotely, using python
Message-ID: <c5ce5132-f4bd-46dc-938c-d4d6fd4dc5b6@x6g2000prc.googlegroups.com>

Hello,

I am new to python and have been trying to figure out how to remotely
add new pages to my confluence
wiki space. I'm running my python script from a linux rhel4 machine
and using confluence version 2.10. As a test I tried to read from
stdin and write a page but it fails- that is, the script runs without
errors but nothing is added.  Does anyone have an example of how this
is done?  Here is my script:

--- begin script -----------
#!/usr/local/bin/python
#
# Reads from standard input, dumps it onto a Confluence page
# You'll need to modify the URL/username/password/spacekey/page title
# below, because I'm too lazy to bother with argv.

import sys
from xmlrpclib import Server

# Read the text of the page from standard input
content = sys.stdin.read()

s = Server("http://confluence.slac.stanford.edu/display/GO/Home")
token = s.confluence1.login("chee", "******")
page = s.confluence1.getPage(token, "SPACEKEY", "TEST Python-2-
Confluence")
page["content"] = content
s.confluence1.storePage(token, page)

newpagedata = {"title":"New Page","content":"new
content","space":"spaceKey"}
newpage = s.confluence1.storePage(token, newpagedata);
------------ end script ------------------------

Any help would be greatly appreciated.

thanks, Pescadero10


From nomail at thank.you  Mon Jul  6 13:41:03 2009
From: nomail at thank.you (jack catcher (nick))
Date: Mon, 06 Jul 2009 20:41:03 +0300
Subject: Python and webcam capture delay?
In-Reply-To: <mailman.2698.1246893772.8015.python-list@python.org>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
Message-ID: <RGq4m.20945$vi5.15615@uutiset.elisa.fi>

Rhodri James kirjoitti:
> On Mon, 06 Jul 2009 07:10:38 +0100, jack catcher (nick) 
> <nomail at thank.you> wrote:
> 
>> Tim Roberts kirjoitti:
>>> "jack catcher (nick)" <nomail at thank.you> wrote:
>>>> I'm thinking of using Python for capturing and showing live webcam 
>>>> stream simultaneously between two computers via local area network. 
>>>> Operating system is Windows. I'm going to begin with VideoCapture 
>>>> extension, no ideas about other implementation yet. Do you have any 
>>>> suggestions on how short delay I should hope to achieve in showing 
>>>> the video? This would be part of a psychological experiment, so I 
>>>> would need to deliver the video stream with a reasonable delay (say, 
>>>> below 100ms).
>>>  You need to do the math on this.  Remember that a full 640x480 RGB 
>>> stream
>>> at 30 frames per second runs 28 megabytes per second.  That's more than
>>> twice what a 100 megabit network can pump.
>>>  You can probably use Python to oversee this, but you might want to 
>>> consider
>>> using lower-level code to control the actual hardware.  If you are
>>> targeting Windows, for example, you could write a DirectShow graph to 
>>> pump
>>> into a renderer that transmits out to a network, then another graph to
>>> receive from the network and display it.
>>>  You can manage the network latency by adding a delays in the local 
>>> graph.
>>
>> Thanks Tim, you're correct about the math. What is your main point 
>> about DirectShow: that it is generally faster and more reliable than 
>> doing the job high-level, or that one could use coding/decoding in 
>> DirectShow to speed up the transmission? I think the latter would be a 
>> great idea if the latency were tolerable. On the other hand, I'd like 
>> to keep things simple and do all the programming in Python. I've got 
>> no experience with DirectShow, but I guess the filters need to be 
>> programmed in C++ and called from Python?
>>
>> Another option might be to use resolution 320x240 at 15fps.
> 
> Does the webcam just deliver frames, or are you getting frames out of
> a decoder layer?  If it's the latter, you want to distribute the encoded
> video, which should be much lower bandwidth.  Exactly how you do that
> depends a bit on what format the webcam claims to deliver.

Well, getting already encoded video from the webcam sounds almost like a 
free lunch (which it probably is not). At least I wouldn't want to get 
too long a delay because of the encoding.

I haven't got the webcam(s) yet, and I guess I can basically purchase 
any ones I find suitable for getting the job done. Any recommendations?


From "sandrodll[remove]" at googlemail.com  Mon Jul  6 13:42:46 2009
From: "sandrodll[remove]" at googlemail.com (gialloporpora)
Date: Mon, 06 Jul 2009 19:42:46 +0200
Subject: Help to find a regular expression to parse po file
In-Reply-To: <mailman.2697.1246893138.8015.python-list@python.org>
References: <4A52084D.1010900@googlemail.com>
	<mailman.2697.1246893138.8015.python-list@python.org>
Message-ID: <4A523796.3050509@googlemail.com>

Risposta al messaggio di MRAB :

> gialloporpora wrote:
>> Hi all,
>> I would like to extract string from a PO file. To do this I have created
>> a little python function to parse po file and extract string:
>>
>> import re
>> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n")
>> m=r.findall(s)
>>
>> where s is a po file like this:
>>
>> msgctxt "write ubiquity commands.description"
>> msgid "Takes you to the Ubiquity<a
>> href=\"chrome://ubiquity/content/editor.html\">command editor</a>  page."
>> msgstr "Apre l'<a href=\"chrome://ubiquity/content/editor.html\">editor
>> dei comandi</a>  di Ubiquity."
>>
>>
>> #. list ubiquity commands command:
>> #. use | to separate multiple name values:
>> msgctxt "list ubiquity commands.names"
>> msgid "list ubiquity commands"
>> msgstr "elenco comandi disponibili"
>>
>> msgctxt "list ubiquity commands.description"
>> msgid "Opens<a href=\"chrome://ubiquity/content/cmdlist.html\">the
>> list</a>\n"
>> "      of all Ubiquity commands available and what they all do."
>> msgstr "Apre una<a
>> href=\"chrome://ubiquity/content/cmdlist.html\">pagina</a>\n"
>> "      in cui sono elencati tutti i comandi disponibili e per ognuno
>> viene spiegato in breve a cosa serve."
>>
>>
>>
>> #. change ubiquity settings command:
>> #. use | to separate multiple name values:
>> msgctxt "change ubiquity settings.names"
>> msgid "change ubiquity settings|change ubiquity preferences|change
>> ubiquity skin"
>> msgstr "modifica impostazioni di ubiquity|modifica preferenze di
>> ubiquity|modifica tema di ubiquity"
>>
>> msgctxt "change ubiquity settings.description"
>> msgid "Takes you to the<a
>> href=\"chrome://ubiquity/content/settings.html\">settings</a>  page,\n"
>> "      where you can change your skin, key combinations, etc."
>> msgstr "Apre la pagina<a
>> href=\"chrome://ubiquity/content/settings.html\">delle impostazioni</a>
>> di Ubiquity,\n"
>> "     dalla quale ?? possibile modificare la combinazione da tastiera
>> utilizzata per richiamare Ubiquity, il tema, ecc."
>>
>>
>>
>> but, obviusly,  with the code above the  last string is not matched. If
>> I use re.DOTALL to match also new line character it not works because it
>> match the entire file, I would like to stop the matching when "msgstr"
>> is found.
>>
>> regex=re.compile("msgid (.*)\\nmsgstr (.*)\\n\\n\\n",re.DOTALL)
>>
>> is it possible or not ?
>>
> You could try:
>
> regex = re.compile(r"msgid (.*(?:\n".*")*)\nmsgstr (.*(?:\n".*")*)$")
>
> and then, if necessary, tidy what you get.


MRAB, thank you for your help, I have tried the code posted by Hallvard 
because I have seen it before and it works. Now I'll check also your 
suggestions.
Sandro

-- 
*Pink Floyd ? The Great Gig in the Sky* - http://sn.im/kggo7
* FAQ* di /it-alt.comp.software.mozilla/: http://bit.ly/1MZ04d


From bdesth.quelquechose at free.quelquepart.fr  Mon Jul  6 13:48:29 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Mon, 06 Jul 2009 19:48:29 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <mailman.2701.1246895207.8015.python-list@python.org>
References: <mailman.2701.1246895207.8015.python-list@python.org>
Message-ID: <4a52548c$0$31414$426a74cc@news.free.fr>

David House a ?crit :
> Hi all,
> 
> I'm looking for some structure advice. I'm writing something that
> currently looks like the following:
> 
> try:
>     <short amount of code that may raise a KeyError>
> except KeyError:
>     <error handler>
> else:
>     <nontrivial amount of code>
> 
> This is working fine. However, I now want to add a call to a function
> in the `else' part that may raise an exception, say a ValueError.

If your error handler terminates the function (which is usually the case 
when using the else clause), you can just skip the else statement, ie:

try:
     <short amount of code that may raise a KeyError>
except KeyError:
     <error handler with early exit>
<nontrivial amount of code>

Then adding one or more try/except is just trivial.


> So I
> was hoping to do something like the following:
> 
> try:
>     <short amount of code that may raise a KeyError>
> except KeyError:
>     <error handler>
> else:
>     <nontrivial amount of code>
> except ValueError:
>     <error handler>
> 
> However, this isn't allowed in Python.

Nope. But this is legal:


try:
     <short amount of code that may raise a KeyError>
except KeyError:
     <error handler>
else:
     try:
         <nontrivial amount of code>
     except ValueError:
         <error handler>



> An obvious way round this is to move the `else' clause into the `try'

"obvious" but not necessarily the best thing to do.

(snip - cf above for simple answers)




From bdesth.quelquechose at free.quelquepart.fr  Mon Jul  6 13:49:49 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Mon, 06 Jul 2009 19:49:49 +0200
Subject: try -> except -> else -> except?
In-Reply-To: <mailman.2707.1246899334.8015.python-list@python.org>
References: <ebe43d680907060846i703f4895xb78536c3e1220d81@mail.gmail.com>
	<mailman.2707.1246899334.8015.python-list@python.org>
Message-ID: <4a5254db$0$31414$426a74cc@news.free.fr>

Python a ?crit :
(snip whole OP)


> as far as I know try has no 'else'

Then you may want to RTFM.



From ethan at stoneleaf.us  Mon Jul  6 13:53:31 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Mon, 06 Jul 2009 10:53:31 -0700
Subject: regex question on .findall and \b
In-Reply-To: <4A4CE2A0.5040407@stoneleaf.us>
References: <4A4CE2A0.5040407@stoneleaf.us>
Message-ID: <4A523A1B.70901@stoneleaf.us>

Many thanks to all who replied!  And, yes, I will *definitely* use raw 
strings from now on.  :)

~Ethan~


From bdesth.quelquechose at free.quelquepart.fr  Mon Jul  6 13:56:00 2009
From: bdesth.quelquechose at free.quelquepart.fr (Bruno Desthuilliers)
Date: Mon, 06 Jul 2009 19:56:00 +0200
Subject: How Python Implements "long integer"?
In-Reply-To: <249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<ce607873-5e20-44f1-b11a-c9f06584461d@g31g2000yqc.googlegroups.com>
	<68c143c9-10b2-4762-9214-f8bfb0b7a9de@37g2000yqp.googlegroups.com>
	<249d9248-ae81-4f51-b734-24e92795aadf@b15g2000yqd.googlegroups.com>
Message-ID: <4a52564e$0$31414$426a74cc@news.free.fr>

Mark Dickinson a ?crit :
> On Jul 5, 1:09 pm, Pedram <pm567... at gmail.com> wrote:
>> Thanks for reply,
>> Sorry I can't explain too clear! I'm not English ;)
> 
> That's shocking.  Everyone should be English. :-)
> 
Mark, tu sors !


From davea at ieee.org  Mon Jul  6 14:28:05 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 14:28:05 -0400
Subject: Why is my code faster with append() in a loop than with a
	large	list?
In-Reply-To: <4A52327B.3000403@mrabarnett.plus.com>
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>	<4A51CD6A.2010106@dejaviewphoto.com>	<4A52089F.7020301@mrabarnett.plus.com>
	<4A522B2D.60407@ieee.org> <4A52327B.3000403@mrabarnett.plus.com>
Message-ID: <4A524235.1010002@ieee.org>

MRAB wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
>> MRAB wrote:
>>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
>>> Angel wrote:
>>> [snip]
>>>> It would probably save some time to not bother storing the zeroes 
>>>> in the list at all.  And it should help if you were to step through 
>>>> a list of primes, rather than trying every possible int.  Or at 
>>>> least constrain yourself to odd numbers (after the initial case of 2).
>>>>
>>> Or stop looking for more factors when you've passed the square root of
>>> num. I don't know what effect there'll be on the time if you 
>>> recalculate
>>> the square root when num changes (expensive calculation vs smaller
>>> search space).
>>>
>>> </div>
>>>
>> But if I remember the code, it stopped when the quotient is one, 
>> which is usually sooner than the square root.  And no need to 
>> precalculate the square root.
>>
> If the number is a large prime then the code will try all the numbers up
> to that, eg if num == 1000003 then it'll try 2..1000003 even though it
> could've given up after 1000.
>
> </div>
>
That's one reason I suggested (and Piet implemented) a sieve.  You can 
stop dividing when the square of the next prime exceeds your quotient.



From tn.pablo at gmail.com  Mon Jul  6 14:49:56 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Mon, 6 Jul 2009 13:49:56 -0500
Subject: A Bug By Any Other Name ...
In-Reply-To: <00df01c9fe33$10c36d80$0d00a8c0@Hendrik>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com> 
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<h2sgiq$6ud$1@ger.gmane.org> 
	<00df01c9fe33$10c36d80$0d00a8c0@Hendrik>
Message-ID: <fdd00b510907061149v5145afa4kd002dce221181fba@mail.gmail.com>

On Mon, Jul 6, 2009 at 07:12, Hendrik van Rooyen<mail at microcorp.co.za> wrote:
> "Terry Reedy" <t...j at ..el.edu> wrote:
>
>> Gabriel Genellina wrote:
>> >
>> > In this case, a note in the documentation warning about the potential
>> > confusion would be fine.
>>
>> How would that help someone who does not read the doc?
>
> It obviously won't.
>
> All it will do, is that it will enable people on this group,
> who may read the manual, to tell people who complain,
> to RTFM.

Yes, it's their problem if they don't read the docs.

>
> ?I agree that it would be a good idea to make it an
> error, or a warning - "this might not do what you
> think it does", or an "are you sure?" exception.
>
> ?:-)
>
> - Hendrik

That would be even harder than adding a line to the docs.  Besides,
the problem that Mr. alex23 pointed: "where do you stop?" would really
get out of hand.

-- 
Pablo Torres N.


From jdnier at gmail.com  Mon Jul  6 14:52:26 2009
From: jdnier at gmail.com (David Niergarth)
Date: Mon, 6 Jul 2009 11:52:26 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <ee914a9f-c654-46b7-86f7-812024c1ea90@g19g2000yql.googlegroups.com>

I remember in college taking an intro programming class (C++) where
the professor started us off writing a program to factor polynomials;
he probably also incorporated binary search into an assignment. But
people don't generally use Python to implement binary search or factor
polynomials so maybe you should start with a problem more germane to
typical novice users (and less algorithm-y). Wouldn't starting them
off with string processing or simple calculations be a practical way
to get comfortable with the language?

--David

On Jul 3, 9:05?am, kj <no.em... at please.post> wrote:
> I'm will be teaching a programming class to novices, and I've run
> into a clear conflict between two of the principles I'd like to
> teach: code clarity vs. code reuse. ?I'd love your opinion about
> it.
>
> The context is the concept of a binary search. ?In one of their
> homeworks, my students will have two occasions to use a binary
> search. ?This seemed like a perfect opportunity to illustrate the
> idea of abstracting commonalities of code into a re-usable function.
> So I thought that I'd code a helper function, called _binary_search,
> that took five parameters: a lower limit, an upper limit, a
> one-parameter function, a target value, and a tolerance (epsilon).
> It returns the value of the parameter for which the value of the
> passed function is within the tolerance of the target value.
>
> This seemed straightforward enough, until I realized that, to be
> useful to my students in their homework, this _binary_search function
> had to handle the case in which the passed function was monotonically
> decreasing in the specified interval...
>
> The implementation is still very simple, but maybe not very clear,
> particularly to programming novices (docstring omitted):
>
> def _binary_search(lo, hi, func, target, epsilon):
> ? ? assert lo < hi
> ? ? assert epsilon > 0
> ? ? sense = cmp(func(hi), func(lo))
> ? ? if sense == 0:
> ? ? ? ? return None
> ? ? target_plus = sense * target + epsilon
> ? ? target_minus = sense * target - epsilon
> ? ? while True:
> ? ? ? ? param = (lo + hi) * 0.5
> ? ? ? ? value = sense * func(param)
> ? ? ? ? if value > target_plus:
> ? ? ? ? ? ? hi = param
> ? ? ? ? elif value < target_minus:
> ? ? ? ? ? ? lo = param
> ? ? ? ? else:
> ? ? ? ? ? ? return param
>
> ? ? ? ? if lo == hi:
> ? ? ? ? ? ? return None
>
> My question is: is the business with sense and cmp too "clever"?
>
> Here's the rub: the code above is more general (hence more reusable)
> by virtue of this trick with the sense parameter, but it is also
> a bit harder to understand.
>
> This not an unusual situation. ?I find that the processing of
> abstracting out common logic often results in code that is harder
> to read, at least for the uninitiated...
>
> I'd love to know your opinions on this.
>
> TIA!
>
> kj



From nobody at nowhere.com  Mon Jul  6 15:41:53 2009
From: nobody at nowhere.com (Nobody)
Date: Mon, 06 Jul 2009 20:41:53 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
Message-ID: <pan.2009.07.06.19.41.52.828000@nowhere.com>

On Mon, 06 Jul 2009 20:41:03 +0300, jack catcher (nick) wrote:

>> Does the webcam just deliver frames, or are you getting frames out of
>> a decoder layer?  If it's the latter, you want to distribute the encoded
>> video, which should be much lower bandwidth.  Exactly how you do that
>> depends a bit on what format the webcam claims to deliver.
> 
> Well, getting already encoded video from the webcam sounds almost like a 
> free lunch (which it probably is not). At least I wouldn't want to get 
> too long a delay because of the encoding.
> 
> I haven't got the webcam(s) yet, and I guess I can basically purchase 
> any ones I find suitable for getting the job done. Any recommendations?

The webcam is bound to do some encoding; most of them use USB "full speed"
(12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.

Chroma subsampling and JPEG compression will both reduce the bandwidth
without introducing noticable latency (the compression time will be no
more than one frame).

Temporal compression will reduce the bandwidth further. Using B-frames
(frames which contain the differences from a predicted frame which is
based upon both previous and subsequent frames) will provide more 
compression, but increases the latency significantly. For this reason, the
compression built into video cameras normally only uses P-frames (frames
which contain the differences from a predicted frame which is based only
upon previous frames).

The biggest issue is likely to be finding latency specifications, followed
by finding a camera which meets your latency requirement.

Also, any "read frame, write frame" loops will add an additional frame of
latency, as you can't start writing the first byte of the frame until
after you've read the last byte of the frame. Video APIs which let you get
rows as they're decoded are rare.



From sisibley at gmail.com  Mon Jul  6 15:43:40 2009
From: sisibley at gmail.com (Scott Sibley)
Date: Mon, 6 Jul 2009 14:43:40 -0500
Subject: Ctypes to wrap libusb-1.0
Message-ID: <cb4d391b0907061243pb47a240jf5288b6fef33cce5@mail.gmail.com>

I have been having issues trying to wrap libusb-1.0 with ctypes. Actually,
there's not much of an issue if I keep everything synchronous, but I need
this to be asynchronous and that is where my problem arises.

Please refer to the following link on Stackoverflow for a full overview of
the issue.

http://stackoverflow.com/questions/1060305/usb-sync-vs-async-vs-semi-async-partially-answered-now

As mentioned in the question on Stackoverflow, synchronous transfers work
great. I wrote an asynchronous C version that works fine. usbmon's output
suggests the transfers are making it through. libusb's debug output shows
nothing out of the ordinary.

I've also asked about this on the libusb mailing list. I've hesitated asking
on the Python mailing list up till now.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/3ef132cd/attachment-0001.html>

From tjreedy at udel.edu  Mon Jul  6 15:55:02 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 15:55:02 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>
Message-ID: <h2tkqm$tlr$1@ger.gmane.org>

Mark Dickinson wrote:
> On Jul 6, 3:32 am, Lawrence D'Oliveiro <l... at geek-
> central.gen.new_zealand> wrote:
>> I wonder how many people have been tripped up by the fact that
>>
>>     ++n
>>
>> and
>>
>>     --n
>>
>> fail silently for numeric-valued n.

Rather few, it seems.

> Recent python-ideas discussion on this subject:
> 
> http://mail.python.org/pipermail/python-ideas/2009-March/003741.html

To add to what I wrote in that thread: it is C, not Python, that is out 
of step with standard usage in math and most languages. --x = x; 1/1/x = 
x; non not a = a; inverse(inverse(f)) = f; etc. And ++x= +x = x 
corresponded to I(I(x)) = I(x) = x, where I is identity function.

In C as high-level assembler, the inc and dec functions are written as 
-- and ++ operators for some mix of the following reasons. 1) They 
correspond to machine language / assembler functions. 2) They need to be 
efficient since they are used in inner loops. Function calls have 
overhead. Original C did not allow inlining of function calls as best I 
remember. 3) They save keystrokes; 4) 2 versions that return pre and 
post change values are needed. My impression is that some opcode sets 
(and hence assemblers) have only one, and efficient code requires 
allowing direct access to whichever one a particular processor supports. 
Basic routines can usually be written either way.

These reasons do not apply to Python or do not fit Python's style.
Anyone who spends 15 minutes skimming the chapter on expressions could 
notice that 5.5. Unary arithmetic and bitwise operations has only +,-, 
and ~ or that the Summary operator table at the end has no -- or ++.

Terry Jan Reedy



From solipsis at pitrou.net  Mon Jul  6 15:58:26 2009
From: solipsis at pitrou.net (Antoine Pitrou)
Date: Mon, 6 Jul 2009 19:58:26 +0000 (UTC)
Subject: Tree structure consuming lot of memory
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
Message-ID: <loom.20090706T195009-310@post.gmane.org>

mayank gupta <mooniitk <at> gmail.com> writes:
> 
> After a little analysis, I found out that in general it uses about
> 1.4 kb of memory for each node!!

How did you measure memory use? Python objects are not very compact, but 1.4KB
per object seems a bit too much (I would expect more about 150-200 bytes/object
in 32-bit mode, or 300-400 bytes/object in 64-bit mode).

One of the solutions is to use __slots__ as already suggested. Another, which
will have similar benefits, is to use a namedtuple. Both suppress the instance
dictionnary (`instance`.__dict__), which is a major contributor to memory
consumption. Illustration (64-bit mode, by the way):

>>> import sys
>>> from collections import namedtuple

# First a normal class
>>> class Node(object): pass
... 
>>> o = Node()
>>> o.value = 1
>>> o.children = ()
>>> 
>>> sys.getsizeof(o)
64
>>> sys.getsizeof(o.__dict__)
280
# The object seems to take a mere 64 bytes, but the attribute dictionnary
# adds a whoppy 280 bytes and bumps actual size to 344 bytes!

# Now a namedtuple (a tuple subclass with property accessors for the various
# tuple items)
>>> Node = namedtuple("Node", "value children")
>>> 
>>> o = Node(value=1, children=())
>>> sys.getsizeof(o)
72
>>> sys.getsizeof(o.__dict__)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'Node' object has no attribute '__dict__'

# The object doesn't have a __dict__, so 72 bytes is its real total size.




From tjreedy at udel.edu  Mon Jul  6 16:27:25 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 16:27:25 -0400
Subject: updating, adding new pages to confluence remotely, using python
In-Reply-To: <c5ce5132-f4bd-46dc-938c-d4d6fd4dc5b6@x6g2000prc.googlegroups.com>
References: <c5ce5132-f4bd-46dc-938c-d4d6fd4dc5b6@x6g2000prc.googlegroups.com>
Message-ID: <h2tmnd$40c$1@ger.gmane.org>

pescadero10 wrote:
> 
> I am new to python and have been trying to figure out how to remotely
> add new pages to my confluence
> wiki space. I'm running my python script from a linux rhel4 machine
> and using confluence version 2.10. As a test I tried to read from
> stdin and write a page but it fails- that is, the script runs without
> errors but nothing is added.  Does anyone have an example of how this
> is done?  Here is my script:
> 
> --- begin script -----------
> #!/usr/local/bin/python
> #
> # Reads from standard input, dumps it onto a Confluence page
> # You'll need to modify the URL/username/password/spacekey/page title
> # below, because I'm too lazy to bother with argv.
> 
> import sys
> from xmlrpclib import Server
> 
> # Read the text of the page from standard input
> content = sys.stdin.read()
> 
> s = Server("http://confluence.slac.stanford.edu/display/GO/Home")
> token = s.confluence1.login("chee", "******")
> page = s.confluence1.getPage(token, "SPACEKEY", "TEST Python-2-
> Confluence")
> page["content"] = content
> s.confluence1.storePage(token, page)
> 
> newpagedata = {"title":"New Page","content":"new
> content","space":"spaceKey"}
> newpage = s.confluence1.storePage(token, newpagedata);
> ------------ end script ------------------------
> 
> Any help would be greatly appreciated.

You neglected to specify Python version.

As near as I can tell from 2.x docs, xmlrpclib has ServerProxy class but 
no Server class. Whoops, just saw "Server is retained as an alias for 
ServerProxy for backwards compatibility. New code should use 
ServerProxy". Good idea -- calling a client 'server' is confusing.

Do you have access to logs on remote machine to see what was received? 
Or to a sysadmin?

tjr



From mooniitk at gmail.com  Mon Jul  6 16:30:28 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Tue, 7 Jul 2009 02:00:28 +0530
Subject: Tree structure consuming lot of memory
In-Reply-To: <loom.20090706T195009-310@post.gmane.org>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<loom.20090706T195009-310@post.gmane.org>
Message-ID: <ff4d16090907061330g48dd9efbr29d2ae4c6622b73b@mail.gmail.com>

I worked out a small code which initializes about 1,000,000 nodes with some
attributes, and saw the memory usage on my linux machine (using 'top'
command). Then just later I averaged out the memory usage per node. I know
this is not the most accurate way but just for estimated value.

The kind of Node class I am working on in my original code is like :

class Node:
     def __init__(self, #attributes ):
             self.coordinates = coordinates
             self.index = index
             self.sibNum = sibNum
             self.branchNum - branchNum

#here 'coordinates' and 'index' are LISTS with length = "dimension", where
"dimension" is a user-input.

The most shocking part of it after the memory-analysis was that, the memory
usage was never dependent on the "dimension". Yeah it varied a bit, but
there wasnt any significant changes in the memory usage even when the
"dimension" was doubled

-- Any clues?

Thank you for all your suggestions till this point.

Regards.




On Tue, Jul 7, 2009 at 1:28 AM, Antoine Pitrou <solipsis at pitrou.net> wrote:

> mayank gupta <mooniitk <at> gmail.com> writes:
> >
> > After a little analysis, I found out that in general it uses about
> > 1.4 kb of memory for each node!!
>
> How did you measure memory use? Python objects are not very compact, but
> 1.4KB
> per object seems a bit too much (I would expect more about 150-200
> bytes/object
> in 32-bit mode, or 300-400 bytes/object in 64-bit mode).
>
> One of the solutions is to use __slots__ as already suggested. Another,
> which
> will have similar benefits, is to use a namedtuple. Both suppress the
> instance
> dictionnary (`instance`.__dict__), which is a major contributor to memory
> consumption. Illustration (64-bit mode, by the way):
>
> >>> import sys
> >>> from collections import namedtuple
>
> # First a normal class
> >>> class Node(object): pass
> ...
> >>> o = Node()
> >>> o.value = 1
> >>> o.children = ()
> >>>
> >>> sys.getsizeof(o)
> 64
> >>> sys.getsizeof(o.__dict__)
> 280
> # The object seems to take a mere 64 bytes, but the attribute dictionnary
> # adds a whoppy 280 bytes and bumps actual size to 344 bytes!
>
> # Now a namedtuple (a tuple subclass with property accessors for the
> various
> # tuple items)
> >>> Node = namedtuple("Node", "value children")
> >>>
> >>> o = Node(value=1, children=())
> >>> sys.getsizeof(o)
> 72
> >>> sys.getsizeof(o.__dict__)
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
> AttributeError: 'Node' object has no attribute '__dict__'
>
> # The object doesn't have a __dict__, so 72 bytes is its real total size.
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/e92881d3/attachment-0001.html>

From thebrasse at gmail.com  Mon Jul  6 16:36:59 2009
From: thebrasse at gmail.com (brasse)
Date: Mon, 6 Jul 2009 13:36:59 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
Message-ID: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>

Hello!

I have been thinking about how write exception safe constructors in
Python. By exception safe I mean a constructor that does not leak
resources when an exception is raised within it. The following is an
example of one possible way to do it:

class Foo(object):
    def __init__(self, name, fail=False):
        self.name = name
        if not fail:
            print '%s.__init__(%s)' % (self.__class__.__name__,
self.name)
        else:
            print '%s.__init__(%s), FAIL' % (self.__class__.__name__,
                                             self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)

class Bar(object):
    def __init__(self):
        try:
            self.a = Foo('a')
            self.b = Foo('b', fail=True)
        except:
            self.close()


    def close(self):
        if hasattr(self, 'a'):
            self.a.close()
        if hasattr(self, 'b'):
            self.b.close()

bar = Bar()

As you can see this is less than straight forward. Is there some kind
of best practice that I'm not aware of?

:.:: mattias


From no.email at please.post  Mon Jul  6 16:40:49 2009
From: no.email at please.post (kj)
Date: Mon, 6 Jul 2009 20:40:49 +0000 (UTC)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
Message-ID: <h2tngh$12s$1@reader1.panix.com>

In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:

>kj a ?crit :
>(snipo
>> To have a special-case
>> re.match() method in addition to a general re.search() method is
>> antithetical to language minimalism,

>FWIW, Python has no pretention to minimalism.

Assuming that you mean by this that Python's authors have no such
pretensions:

"There is real value in having a small language."

			Guido van Rossum, 2007.07.03
			http://mail.python.org/pipermail/python-3000/2007-July/008663.html

So there.

BTW, that's just one example.  I've seen similar sentiments expressed
by Guido over and over and over: any new proposed enhancement to
Python must be good enough in his mind to justify cluttering the
language.  That attitude counts as minimalism in my book.

The best explanation I have found so far for re.match is that it
is an unfortunate bit of legacy, something that would not be there
if the design of Python did not have to be mindful of keeping old
code chugging along...

kj


From joshua at joshuakugler.com  Mon Jul  6 16:45:45 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Mon, 06 Jul 2009 12:45:45 -0800
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
Message-ID: <h2tnpp$6if$1@ger.gmane.org>

Paul Moore wrote:
> The SQLite documentation mentions a flag, SQLITE_OPEN_READONLY, to
> open a database read only. I can't find any equivalent documented in
> the Python standard library documentation for the sqlite3 module (or,
> for that matter, on the pysqlite library's website).
> 
> Is it possible to open a sqlite database in readonly mode, in Python?

Yes, but most likely not with pysqlite.  The python sqlite3 module in the
standard library, and the pysqlite module are both DB-API compliant, which
means they probably do not have a method to open the DB read only (as that
is usually enforced at the user permission level).

If you want to use that flag, take a look at APSW. It is a very thin layer
on top of the SQLite C API, and thus supports everything that the C API
supports.  It is not, however, DB API compliant, but is very close so not
hard to pick up.

BTW, APSW is written by the same author as pysqlite.

j




From clp2 at rebertia.com  Mon Jul  6 17:03:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 14:03:48 -0700
Subject: Tree structure consuming lot of memory
In-Reply-To: <ff4d16090907061330g48dd9efbr29d2ae4c6622b73b@mail.gmail.com>
References: <ff4d16090907060255l7d286bfbu60c3d87109b9b753@mail.gmail.com>
	<loom.20090706T195009-310@post.gmane.org>
	<ff4d16090907061330g48dd9efbr29d2ae4c6622b73b@mail.gmail.com>
Message-ID: <50697b2c0907061403s16c0602cp5d3767772e6e8ba@mail.gmail.com>

> On Tue, Jul 7, 2009 at 1:28 AM, Antoine Pitrou <solipsis at pitrou.net> wrote:
>>
>> mayank gupta <mooniitk <at> gmail.com> writes:
>> >
>> > After a little analysis, I found out that in general it uses about
>> > 1.4 kb of memory for each node!!
>>
>> How did you measure memory use? Python objects are not very compact, but
>> 1.4KB
>> per object seems a bit too much (I would expect more about 150-200
>> bytes/object
>> in 32-bit mode, or 300-400 bytes/object in 64-bit mode).
>>
>> One of the solutions is to use __slots__ as already suggested. Another,
>> which
>> will have similar benefits, is to use a namedtuple. Both suppress the
>> instance
>> dictionnary (`instance`.__dict__), which is a major contributor to memory
>> consumption. Illustration (64-bit mode, by the way):
>>
>> >>> import sys
>> >>> from collections import namedtuple
>>
>> # First a normal class
>> >>> class Node(object): pass
>> ...
>> >>> o = Node()
>> >>> o.value = 1
>> >>> o.children = ()
>> >>>
>> >>> sys.getsizeof(o)
>> 64
>> >>> sys.getsizeof(o.__dict__)
>> 280
>> # The object seems to take a mere 64 bytes, but the attribute dictionnary
>> # adds a whoppy 280 bytes and bumps actual size to 344 bytes!
>>
>> # Now a namedtuple (a tuple subclass with property accessors for the
>> various
>> # tuple items)
>> >>> Node = namedtuple("Node", "value children")
>> >>>
>> >>> o = Node(value=1, children=())
>> >>> sys.getsizeof(o)
>> 72
>> >>> sys.getsizeof(o.__dict__)
>> Traceback (most recent call last):
>> ?File "<stdin>", line 1, in <module>
>> AttributeError: 'Node' object has no attribute '__dict__'
>>
>> # The object doesn't have a __dict__, so 72 bytes is its real total size.
On Mon, Jul 6, 2009 at 1:30 PM, mayank gupta<mooniitk at gmail.com> wrote:
> I worked out a small code which initializes about 1,000,000 nodes with some
> attributes, and saw the memory usage on my linux machine (using 'top'
> command). Then just later I averaged out the memory usage per node. I know
> this is not the most accurate way but just for estimated value.

You should try the more accurate sys.getsizeof() function:
http://docs.python.org/library/sys.html#sys.getsizeof

Cheers,
Chris

P.S. Please don't top-post in the future.
-- 
http://blog.rebertia.com


From deets at nospam.web.de  Mon Jul  6 17:10:28 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 06 Jul 2009 23:10:28 +0200
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <7bf7i4F2350o5U1@mid.uni-berlin.de>

kj schrieb:
> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
> 
>> kj a ?crit :
>> (snipo
>>> To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism,
> 
>> FWIW, Python has no pretention to minimalism.
> 
> Assuming that you mean by this that Python's authors have no such
> pretensions:
> 
> "There is real value in having a small language."
> 
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
> 
> So there.
> 
> BTW, that's just one example.  I've seen similar sentiments expressed
> by Guido over and over and over: any new proposed enhancement to
> Python must be good enough in his mind to justify cluttering the
> language.  That attitude counts as minimalism in my book.
> 
> The best explanation I have found so far for re.match is that it
> is an unfortunate bit of legacy, something that would not be there
> if the design of Python did not have to be mindful of keeping old
> code chugging along...

language != libraries.

Diez


From Scott.Daniels at Acm.Org  Mon Jul  6 17:15:44 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 06 Jul 2009 14:15:44 -0700
Subject: Cleaning up after failing to contructing objects
In-Reply-To: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
Message-ID: <MeqdnTn37r9N-s_XnZ2dnUVZ_jCdnZ2d@pdx.net>

brasse wrote:
> I have been thinking about how write exception safe constructors in
> Python. By exception safe I mean a constructor that does not leak
> resources when an exception is raised within it. 
...
 > As you can see this is less than straight forward. Is there some kind
 > of best practice that I'm not aware of?

Not so tough.  Something like this tweaked version of your example:

class Foo(object):
     def __init__(self, name, fail=False):
         self.name = name
         if not fail:
             print '%s.__init__(%s)' % (type(self).__name__, name)
         else:
             print '%s.__init__(%s), FAIL' % (type(self).__name__, name)
             raise ValueError('Asked to fail: %r' % fail)

     def close(self):
         print '%s.close(%s)' % (type(self).__name__, self.name)


class Bar(object):
     def __init__(self):
         unwind = []
         try:
             self.a = Foo('a')
             unwind.append(a)
             self.b = Foo('b', fail=True)
             unwind.append(b)
             ...
         except Exception, why:
             while unwind):
                 unwind.pop().close()
             raise

bar = Bar()

--Scott David Daniels
Scott.Daniels at Acm.Org


From macaodha at gmail.com  Mon Jul  6 17:36:37 2009
From: macaodha at gmail.com (Oisin)
Date: Mon, 6 Jul 2009 14:36:37 -0700 (PDT)
Subject: getting text from webpage that has embedded flash
Message-ID: <8aaca352-e115-4aa8-b76d-a37a0edf7a74@h31g2000yqd.googlegroups.com>

HI,

Im trying to parse a bands myspace page and get the total number of
plays for their songs. e.g. http://www.myspace.com/mybloodyvalentine

The problem is that I cannot use urllib2 as the "Total plays" string
does not appear in the page source.

Any idea of ways around this?

Thanks,
O


From michaelmossey at gmail.com  Mon Jul  6 17:37:53 2009
From: michaelmossey at gmail.com (Michael Mossey)
Date: Mon, 6 Jul 2009 14:37:53 -0700 (PDT)
Subject: Catching control-C
Message-ID: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>

What is required in a python program to make sure it catches a control-
c on the command-line? Do some i/o? The OS here is Linux.

Thanks,
Mike


From clp2 at rebertia.com  Mon Jul  6 17:44:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 14:44:20 -0700
Subject: Catching control-C
In-Reply-To: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
Message-ID: <50697b2c0907061444x1a361d47j7c3eeb610431a8ba@mail.gmail.com>

On Mon, Jul 6, 2009 at 2:37 PM, Michael Mossey<michaelmossey at gmail.com> wrote:
> What is required in a python program to make sure it catches a control-
> c on the command-line? Do some i/o? The OS here is Linux.

try:
    #code that reads input
except KeyboardInterrupt:
    #Ctrl-C was pressed

Cheers,
Chris
-- 
http://blog.rebertia.com


From philip at semanchuk.com  Mon Jul  6 17:47:57 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 17:47:57 -0400
Subject: Catching control-C
In-Reply-To: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
Message-ID: <928186A7-E76E-4BF3-8696-DC61ED025B99@semanchuk.com>


On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:

> What is required in a python program to make sure it catches a  
> control-
> c on the command-line? Do some i/o? The OS here is Linux.

You can use a try/except to catch a KeyboardInterrupt exception, or  
you can trap it using the signal module:
http://docs.python.org/library/signal.html

You want to trap SIGINT.


HTH
Philip


From michaelmossey at gmail.com  Mon Jul  6 18:02:26 2009
From: michaelmossey at gmail.com (Michael Mossey)
Date: Mon, 6 Jul 2009 15:02:26 -0700 (PDT)
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
Message-ID: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>

On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>
> > What is required in a python program to make sure it catches a ?
> > control-
> > c on the command-line? Do some i/o? The OS here is Linux.
>
> You can use a try/except to catch a KeyboardInterrupt exception, or ?
> you can trap it using the signal module:http://docs.python.org/library/signal.html
>
> You want to trap SIGINT.
>
> HTH
> Philip

Thanks to both of you. However, my question is also about whether I
need to be doing i/o or some similar operation for my program to
notice in any shape or form that Control-C has been pressed. In the
past, I've written Python programs that go about their business
ignoring Ctrl-C. Other programs respond to it immediately by exiting.
I think the difference is that the latter programs are doing i/o. But
I want to understand better what the "secret" is to responding to a
ctrl-C in any shape or form.

For example, does trapping SIGINT always work, regardless of what my
process is doing?

Thanks,
Mike


From nile_mcadams at yahoo.com  Mon Jul  6 18:02:45 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Mon, 6 Jul 2009 15:02:45 -0700 (PDT)
Subject: Semi-Newbie needs a little help
Message-ID: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>

I am trying to write a simple little program to do some elementary
stock market analysis.  I read lines, send each line to a function and
then the function returns a date which serves as a key to a
dictionary. Each time a date is returned I want to increment the value
associated with that date. The function seems to be working properly.
By means of a print statement I have inserted just before the return
value I can see there are three dates that are returned which is
correct.  The dictionary only seems to capture the last date. My test
data consists of five stocks, each stock with five days. The correct
answer would be a count of 5 for the second day, the third day, and
the last day -- 11/14/2008.

Here is the a code, followed by a portion of the output.  I know
enough to write simple little programs like this with no problems up
until now but I don't know enough to figure out what I am doing
wrong.

Code

    for x in range(len(file_list)):
    d = open(file_list[x] , "r")
    data = d.readlines()
    k = above_or_below(data)                                # This
function seems to work correctly
    print "here is the value that was returned " , k
    dict[k] = dict.get(k,0) + 1

    dict_list = dict.values()
    print "here is a list of the dictionary values ", dict_list
    print "the length of the dictionary is ", len(dict)

And here is some output
    Function will return k which = 11/11/2008   #  These 3 lines are
printed from the function just before the return
    Function will return k which = 11/12/2008   #   This sample shows
stocks 4 and 5 but 1,2,3 are the same.
    Function will return k which = 11/14/2008
    here is the value that was returned 11/14/2008     # printed from
code above  - only the last day seems to be
    Function will return k which = 11/11/2008             #
recognized.
    Function will return k which = 11/12/2008
    Function will return k which = 11/14/2008
    here is the value that was returned 11/14/2008
    here is a list of the dictionary values [5]             # dict has
counted only the last day for 5 stocks
    the length of the dictionary is 1
    >Exit code: 0





From philip at semanchuk.com  Mon Jul  6 18:16:06 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Mon, 6 Jul 2009 18:16:06 -0400
Subject: Catching control-C
In-Reply-To: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <A9CD4C3C-0617-48D8-BC29-2D2E2E1BF6D2@semanchuk.com>


On Jul 6, 2009, at 6:02 PM, Michael Mossey wrote:

> On Jul 6, 2:47 pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>>
>>> What is required in a python program to make sure it catches a
>>> control-
>>> c on the command-line? Do some i/o? The OS here is Linux.
>>
>> You can use a try/except to catch a KeyboardInterrupt exception, or
>> you can trap it using the signal module:http://docs.python.org/library/signal.html
>>
>> You want to trap SIGINT.
>>
>> HTH
>> Philip
>
> Thanks to both of you. However, my question is also about whether I
> need to be doing i/o or some similar operation for my program to
> notice in any shape or form that Control-C has been pressed. In the
> past, I've written Python programs that go about their business
> ignoring Ctrl-C. Other programs respond to it immediately by exiting.
> I think the difference is that the latter programs are doing i/o. But
> I want to understand better what the "secret" is to responding to a
> ctrl-C in any shape or form.
>
> For example, does trapping SIGINT always work, regardless of what my
> process is doing?

Hi Mike,
Sorry, I don't know the Python internals well enough to answer your  
question.

Good luck
Philip



From clp2 at rebertia.com  Mon Jul  6 18:22:54 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 15:22:54 -0700
Subject: Semi-Newbie needs a little help
In-Reply-To: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>

On Mon, Jul 6, 2009 at 3:02 PM, Nile<nile_mcadams at yahoo.com> wrote:
> I am trying to write a simple little program to do some elementary
> stock market analysis. ?I read lines, send each line to a function and
> then the function returns a date which serves as a key to a
> dictionary. Each time a date is returned I want to increment the value
> associated with that date. The function seems to be working properly.
> By means of a print statement I have inserted just before the return
> value I can see there are three dates that are returned which is
> correct. ?The dictionary only seems to capture the last date. My test
> data consists of five stocks, each stock with five days. The correct
> answer would be a count of 5 for the second day, the third day, and
> the last day -- 11/14/2008.
>
> Here is the a code, followed by a portion of the output. ?I know
> enough to write simple little programs like this with no problems up
> until now but I don't know enough to figure out what I am doing
> wrong.

> ? ?for x in range(len(file_list)):

for filename in file_list:
#I'm assuming the lack of indentation on the subsequent lines is a
mere transcription error...

> ? ?d = open(file_list[x] , "r")

    d = open(filename , "r")

> ? ?data = d.readlines()
> ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> function seems to work correctly
> ? ?print "here is the value that was returned " , k
> ? ?dict[k] = dict.get(k,0) + 1

`dict` is the name of a builtin type. Please rename this variable to
avoid shadowing the type.
Also, where is this variable even initialized? It's not in this code
snippet you gave.
Further, I would recommend using a defaultdict
(http://docs.python.org/dev/library/collections.html#collections.defaultdict)
rather than a regular dictionary; this would make the
count-incrementing part nicer.

Taking these changes into account, your code becomes:

from collections import defaultdict

counts = defaultdict(lambda: 0)

for filename in file_list:
    d = open(filename , "r")
    data = d.readlines()
    k = above_or_below(data) # This function seems to work correctly
    print "here is the value that was returned " , k
    counts[k] += 1

    values = counts.values()
    print "here is a list of the dictionary values ", values
    print "the length of the dictionary is ", len(counts)


I don't immediately see what's causing your problem, but guess that it
might've be related to the initialization of the `dict` variable.

Cheers,
Chris
-- 
http://blog.rebertia.com


From tn.pablo at gmail.com  Mon Jul  6 18:30:21 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Mon, 6 Jul 2009 17:30:21 -0500
Subject: Semi-Newbie needs a little help
In-Reply-To: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <fdd00b510907061530g42c6599er6f689c84ca59ca68@mail.gmail.com>

On Mon, Jul 6, 2009 at 17:02, Nile<nile_mcadams at yahoo.com> wrote:
> Code
>
> ? ?for x in range(len(file_list)):
> ? ?d = open(file_list[x] , "r")
> ? ?data = d.readlines()
> ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> function seems to work correctly
> ? ?print "here is the value that was returned " , k
> ? ?dict[k] = dict.get(k,0) + 1
>
> ? ?dict_list = dict.values()
> ? ?print "here is a list of the dictionary values ", dict_list
> ? ?print "the length of the dictionary is ", len(dict)

Correcting your indentation errors and moving your comments above the
line they reference will attract more help from others in this list
;-)

Also, I'd recommend limiting your line length to 80 chars, since lines
are wrapped anyway.


-- 
Pablo Torres N.


From bcharrow at csail.mit.edu  Mon Jul  6 18:38:12 2009
From: bcharrow at csail.mit.edu (Ben Charrow)
Date: Mon, 06 Jul 2009 18:38:12 -0400
Subject: Catching control-C
In-Reply-To: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <4A527CD4.3010406@csail.mit.edu>

Michael Mossey wrote:
> On Jul 6, 2:47 pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>> 
>>> What is required in a python program to make sure it catches a control- 
>>> c on the command-line? Do some i/o? The OS here is Linux.
>> You can use a try/except to catch a KeyboardInterrupt exception, or you 
>> can trap it using the signal 
>> module:http://docs.python.org/library/signal.html
>> 
>> You want to trap SIGINT.
>> 
>> HTH Philip
> 
> Thanks to both of you. However, my question is also about whether I need to 
> be doing i/o or some similar operation for my program to notice in any shape
>  or form that Control-C has been pressed.

You don't need to be doing I/O in order to raise a KeyboardIneterrupt.  For
example, the following program should use up a lot of your CPU until you
hit Ctrl-C.

>>> while True:
...     pass
...
^CTraceback (most recent call last):
  File "<stdin>", line 1, in <module>
KeyboardInterrupt

> In the past, I've written Python programs that go about their business 
> ignoring Ctrl-C.

Can you be more specific?  Can you share the relevant sections of these
programs?  Were these programs multi-threaded?

> But I want to understand better what the "secret" is to responding to a 
> ctrl-C in any shape or form.

Strictly speaking, I don't think you can always respond to a Ctrl-C in any
shape or form.  Quoting from the signal module:

Although Python signal handlers are called asynchronously as far as the Python
user is concerned, they can only occur between the "atomic" instructions of the
Python interpreter. This means that signals arriving during long calculations
implemented purely in C (such as regular expression matches on large bodies of
text) may be delayed for an arbitrary amount of time.

HTH,
Ben



From python at mrabarnett.plus.com  Mon Jul  6 18:49:41 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 06 Jul 2009 23:49:41 +0100
Subject: Semi-Newbie needs a little help
In-Reply-To: <50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>
Message-ID: <4A527F85.7030400@mrabarnett.plus.com>

Chris Rebert wrote:
> On Mon, Jul 6, 2009 at 3:02 PM, Nile<nile_mcadams at yahoo.com> wrote:
>> I am trying to write a simple little program to do some elementary
>> stock market analysis.  I read lines, send each line to a function and
>> then the function returns a date which serves as a key to a
>> dictionary. Each time a date is returned I want to increment the value
>> associated with that date. The function seems to be working properly.
>> By means of a print statement I have inserted just before the return
>> value I can see there are three dates that are returned which is
>> correct.  The dictionary only seems to capture the last date. My test
>> data consists of five stocks, each stock with five days. The correct
>> answer would be a count of 5 for the second day, the third day, and
>> the last day -- 11/14/2008.
>>
>> Here is the a code, followed by a portion of the output.  I know
>> enough to write simple little programs like this with no problems up
>> until now but I don't know enough to figure out what I am doing
>> wrong.
> 
>>    for x in range(len(file_list)):
> 
> for filename in file_list:
> #I'm assuming the lack of indentation on the subsequent lines is a
> mere transcription error...
> 
>>    d = open(file_list[x] , "r")
> 
>     d = open(filename , "r")
> 
>>    data = d.readlines()
>>    k = above_or_below(data)                                # This
>> function seems to work correctly
>>    print "here is the value that was returned " , k
>>    dict[k] = dict.get(k,0) + 1
> 
> `dict` is the name of a builtin type. Please rename this variable to
> avoid shadowing the type.
> Also, where is this variable even initialized? It's not in this code
> snippet you gave.
> Further, I would recommend using a defaultdict
> (http://docs.python.org/dev/library/collections.html#collections.defaultdict)
> rather than a regular dictionary; this would make the
> count-incrementing part nicer.
> 
> Taking these changes into account, your code becomes:
> 
> from collections import defaultdict
> 
> counts = defaultdict(lambda: 0)
> 
Better is:

counts = defaultdict(int)

> for filename in file_list:
>     d = open(filename , "r")
>     data = d.readlines()
>     k = above_or_below(data) # This function seems to work correctly
>     print "here is the value that was returned " , k
>     counts[k] += 1
> 
>     values = counts.values()
>     print "here is a list of the dictionary values ", values
>     print "the length of the dictionary is ", len(counts)
> 
> 
> I don't immediately see what's causing your problem, but guess that it
> might've be related to the initialization of the `dict` variable.
> 
It might be that the indentation was wrong where the count is
incremented, but I can't tell because none of the lines were shown
indented.


From p.f.moore at gmail.com  Mon Jul  6 18:50:08 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Mon, 6 Jul 2009 23:50:08 +0100
Subject: Opening a SQLite database in readonly mode
In-Reply-To: <h2tnpp$6if$1@ger.gmane.org>
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org>
Message-ID: <79990c6b0907061550o43df92c0qec1fe2c7e49b916@mail.gmail.com>

2009/7/6 Joshua Kugler <joshua at joshuakugler.com>:
> Paul Moore wrote:
>> The SQLite documentation mentions a flag, SQLITE_OPEN_READONLY, to
>> open a database read only. I can't find any equivalent documented in
>> the Python standard library documentation for the sqlite3 module (or,
>> for that matter, on the pysqlite library's website).
>>
>> Is it possible to open a sqlite database in readonly mode, in Python?
>
> Yes, but most likely not with pysqlite. ?The python sqlite3 module in the
> standard library, and the pysqlite module are both DB-API compliant, which
> means they probably do not have a method to open the DB read only (as that
> is usually enforced at the user permission level).
>
> If you want to use that flag, take a look at APSW. It is a very thin layer
> on top of the SQLite C API, and thus supports everything that the C API
> supports. ?It is not, however, DB API compliant, but is very close so not
> hard to pick up.
>
> BTW, APSW is written by the same author as pysqlite.

Excellent, thanks. I'll have to think whether I want the extra
dependency but at least I know it's possible now.

Thanks for the pointer.
Paul.


From nile_mcadams at yahoo.com  Mon Jul  6 18:50:59 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Mon, 6 Jul 2009 15:50:59 -0700 (PDT)
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2725.1246919443.8015.python-list@python.org>
Message-ID: <c251a5aa-aab2-48af-8583-9ff040a0a393@d4g2000yqa.googlegroups.com>

On Jul 6, 5:30?pm, "Pablo Torres N." <tn.pa... at gmail.com> wrote:
> On Mon, Jul 6, 2009 at 17:02, Nile<nile_mcad... at yahoo.com> wrote:
> > Code
>
> > ? ?for x in range(len(file_list)):
> > ? ?d = open(file_list[x] , "r")
> > ? ?data = d.readlines()
> > ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> > function seems to work correctly
> > ? ?print "here is the value that was returned " , k
> > ? ?dict[k] = dict.get(k,0) + 1
>
> > ? ?dict_list = dict.values()
> > ? ?print "here is a list of the dictionary values ", dict_list
> > ? ?print "the length of the dictionary is ", len(dict)
>
> Correcting your indentation errors and moving your comments above the
> line they reference will attract more help from others in this list
> ;-)
>
> Also, I'd recommend limiting your line length to 80 chars, since lines
> are wrapped anyway.
>
> --
> Pablo Torres N.

Yup - Sorry, first post ever - next ones will be better formatted


From piet at cs.uu.nl  Mon Jul  6 18:51:24 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 00:51:24 +0200
Subject: Why is my code faster with append() in a loop than with a large
	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<mailman.2683.1246875006.8015.python-list@python.org>
	<m2r5wtetb0.fsf@cs.uu.nl>
	<U6qdnQKfHa7Dt8_XnZ2dnUVZ_hmdnZ2d@pdx.net>
Message-ID: <m2d48de87n.fsf@cs.uu.nl>

>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) wrote:

>SDD>      # No need for global declarations, we alter, not replace

Yes, I know, but I find it neater to do the global declarations, if only
for documentation. And they don't affect the run time, only the compile
time. 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From matt0177 at GMAIL.COM  Mon Jul  6 18:56:40 2009
From: matt0177 at GMAIL.COM (matt0177)
Date: Mon, 6 Jul 2009 15:56:40 -0700 (PDT)
Subject: Python Error from Apress book
Message-ID: <24364269.post@talk.nabble.com>


http://www.nabble.com/file/p24364269/simple_markup2.py simple_markup2.py 
http://www.nabble.com/file/p24364269/util2.py util2.py 

The two above files are from chapter 20 of the Apress book "Beginning Python
>From Novice to Professional". When I try to run the command as outlined in
the book "simple_markup2.py < test_input.txt > test_output.html i get the
following error every time.

File "C:\Python25\Scripts\simple_markup2.py", line 7, in <module> for block
in blocks(sys.stdin):
File "C:\Python25\Scripts\util2.py", line 7, in blocks for line in
lines(file):
File "C:\Python25\Scripts\util2.py", line 2, in lines for line in file:
yield line
IOError: [Errno 9] Bad file descriptor

I've tried this code on two different computers (both winxp, python 2.5.1)
with the same results. when simple_markup2.py is run with only output, it
will correctly write the headers. When you try to add an input file, you get
the error every time, and I have tried every text file known to man,
including the downloadable sample. This has been frustrating me for several
days, any advice would be greatly appreciated. I'm just starting to learn
python so troubleshooting is a sorely lacked skill atm :)

Thanks,

Matt


-- 
View this message in context: http://www.nabble.com/Python-Error-from-Apress-book-tp24364269p24364269.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From hannarosie at gmail.com  Mon Jul  6 18:57:20 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Mon, 6 Jul 2009 15:57:20 -0700
Subject: Write matrix to text file
Message-ID: <564970db0907061557s2c559b3cxaf52859abd2050a3@mail.gmail.com>

Hi,

I'm working with both python and matlab at the moment and I was wondering if
there is an efficient way to take a 2-D array (of 1s and 0s) in python and
write it to a text file such that matlab will be able to create a sparse
matrix from it later.

Thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090706/64497bc8/attachment-0001.html>

From piet at cs.uu.nl  Mon Jul  6 18:58:00 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 00:58:00 +0200
Subject: Why is my code faster with append() in a loop than with a
	large	list?
References: <2d56febf0907051720y1958c08flc1e67ed55700bfd5@mail.gmail.com>
	<4A51CD6A.2010106@dejaviewphoto.com>
	<4A52089F.7020301@mrabarnett.plus.com>
	<mailman.2705.1246899107.8015.python-list@python.org>
Message-ID: <m28wj1e7wn.fsf@cs.uu.nl>

>>>>> Dave Angel <davea at ieee.org> (DA) wrote:

>DA> MRAB wrote:
>>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave Angel
>>> wrote:
>>> [snip]
>>>> It would probably save some time to not bother storing the zeroes in the
>>>> list at all.  And it should help if you were to step through a list of
>>>> primes, rather than trying every possible int.  Or at least constrain
>>>> yourself to odd numbers (after the initial case of 2).
>>>> 
>>> Or stop looking for more factors when you've passed the square root of
>>> num. I don't know what effect there'll be on the time if you recalculate
>>> the square root when num changes (expensive calculation vs smaller
>>> search space).
>>> 
>>> </div>
>>> 
>DA> But if I remember the code, it stopped when the quotient is one, which is
>DA> usually sooner than the square root.  And no need to precalculate the
>DA> square root.

That's right. I thought of doing the sqrt trick by testing for num <
factor, i.e."

        if num < factor:
            break
but found out that it is useless, as for each factor found, num is
divided by that factor as many times as possible. Therefore when the
largest prime factor of num has been found, num ends up being 1 and the
loop stops.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nacim_bravo at agilent.com  Mon Jul  6 19:00:39 2009
From: nacim_bravo at agilent.com (nacim_bravo at agilent.com)
Date: Mon, 6 Jul 2009 17:00:39 -0600
Subject: Newbie needs help
In-Reply-To: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>

Dear Python gurus,

If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?

Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment? 

Please let me know, 
nacim




From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:03:00 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:03:00 +0100
Subject: Python and webcam capture delay?
In-Reply-To: <RGq4m.20945$vi5.15615@uutiset.elisa.fi>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
Message-ID: <op.uwn4za1za8ncjz@gnudebst>

On Mon, 06 Jul 2009 18:41:03 +0100, jack catcher (nick) <nomail at thank.you>  
wrote:

> Rhodri James kirjoitti:
>>  Does the webcam just deliver frames, or are you getting frames out of
>> a decoder layer?  If it's the latter, you want to distribute the encoded
>> video, which should be much lower bandwidth.  Exactly how you do that
>> depends a bit on what format the webcam claims to deliver.
>
> Well, getting already encoded video from the webcam sounds almost like a  
> free lunch (which it probably is not). At least I wouldn't want to get  
> too long a delay because of the encoding.

Not so unlikely as you might think, since there are very basic M-JPEG and
MPEG-2 on-chip encoders available, and the webcam will have to do some
compression to get the video data into the computer.  USB is not as fast
as it would like to pretend.

> I haven't got the webcam(s) yet, and I guess I can basically purchase  
> any ones I find suitable for getting the job done. Any recommendations?

Sorry, no.  I'm used to getting my video feeds down fibre-optic cables :-)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Mon Jul  6 19:05:44 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 01:05:44 +0200
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
Message-ID: <m24otpe7jr.fsf@cs.uu.nl>

>>>>> Philip Semanchuk <philip at semanchuk.com> (PS) wrote:

>PS> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:

>>> What is required in a python program to make sure it catches a  control-
>>> c on the command-line? Do some i/o? The OS here is Linux.

>PS> You can use a try/except to catch a KeyboardInterrupt exception, or  you
>PS> can trap it using the signal module:
>PS> http://docs.python.org/library/signal.html

>PS> You want to trap SIGINT.

And make sure threads don't mess up the signal handling.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:16:00 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:16:00 +0100
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <op.uwn5kya6a8ncjz@gnudebst>

On Mon, 06 Jul 2009 21:40:49 +0100, kj <no.email at please.post> wrote:

> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers  
> <bruno.42.desthuilliers at websiteburo.invalid> writes:
>
>> kj a ?crit :
>> (snipo
>>> To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism,
>
>> FWIW, Python has no pretention to minimalism.
>
> Assuming that you mean by this that Python's authors have no such
> pretensions:
>
> "There is real value in having a small language."
>
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html

re.match() is part of the library, not the language.  The standard
library is in no sense of the word small.  It has a mild tendency
to avoid repeating itself, but presumably the stonkingly obvious
optimisation possibilities of re.match() over re.search() are
considered worth the (small) increase in size.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:20:48 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:20:48 +0100
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
Message-ID: <op.uwn5syxha8ncjz@gnudebst>

On Tue, 07 Jul 2009 00:00:39 +0100, <nacim_bravo at agilent.com> wrote:

> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it  
> possible to do such in Python environment? If yes, how to do or what  
> syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible  
> to get this value in Python environment?

Quite possibly, however you're going to have to give us a *lot* more
information before the answers you get will be worth anything at all.
How is "the certain material" represented?  What simulator are you
using?  Which Python environment?  Which Python version for that matter?

We may appear to be mind-readers, but we usually need a bit more
than this to work on.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Mon Jul  6 19:23:57 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 00:23:57 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <4A522C4B.20102@ieee.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<op.uwninxtza8ncjz@gnudebst> <4A522C4B.20102@ieee.org>
Message-ID: <op.uwn5x7dua8ncjz@gnudebst>

On Mon, 06 Jul 2009 17:54:35 +0100, Dave Angel <davea at ieee.org> wrote:

> Rhodri James wrote:
>> Indeed, arguably it's a bug for C compilers to fail to find the valid
>> parsing of "++5" as "+(+5)".  All I can say is that I've never even
>> accidentally typed that in twenty years of C programming.
>>
> But the C language specifically defines the tokenizer as doing a  
> max-match, finding the longest legal token at any point.  That's how  
> many things that would otherwise be ambiguous are well-defined.  For  
> example, if you want to divide two integers, given pointers to them, you  
> need a space between the slash and the start.
>          *p1/*p2    begins a comment,  while   *p1/ *p2   does a division

You know, I've never had that come up either!  My habit of sticking spaces
around binary operators purely for legibility probably helped, but I'm
still a bit boggled.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From nile_mcadams at yahoo.com  Mon Jul  6 19:29:36 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Mon, 6 Jul 2009 16:29:36 -0700 (PDT)
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2724.1246918979.8015.python-list@python.org>
Message-ID: <c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>

On Jul 6, 5:22?pm, Chris Rebert <c... at rebertia.com> wrote:
> On Mon, Jul 6, 2009 at 3:02 PM, Nile<nile_mcad... at yahoo.com> wrote:
> > I am trying to write a simple little program to do some elementary
> > stock market analysis. ?I read lines, send each line to a function and
> > then the function returns a date which serves as a key to a
> > dictionary. Each time a date is returned I want to increment the value
> > associated with that date. The function seems to be working properly.
> > By means of a print statement I have inserted just before the return
> > value I can see there are three dates that are returned which is
> > correct. ?The dictionary only seems to capture the last date. My test
> > data consists of five stocks, each stock with five days. The correct
> > answer would be a count of 5 for the second day, the third day, and
> > the last day -- 11/14/2008.
>
> > Here is the a code, followed by a portion of the output. ?I know
> > enough to write simple little programs like this with no problems up
> > until now but I don't know enough to figure out what I am doing
> > wrong.
> > ? ?for x in range(len(file_list)):
>
> for filename in file_list:
> #I'm assuming the lack of indentation on the subsequent lines is a
> mere transcription error...
>
> > ? ?d = open(file_list[x] , "r")
>
> ? ? d = open(filename , "r")
>
> > ? ?data = d.readlines()
> > ? ?k = above_or_below(data) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?# This
> > function seems to work correctly
> > ? ?print "here is the value that was returned " , k
> > ? ?dict[k] = dict.get(k,0) + 1
>
> `dict` is the name of a builtin type. Please rename this variable to
> avoid shadowing the type.
> Also, where is this variable even initialized? It's not in this code
> snippet you gave.
> Further, I would recommend using a defaultdict
> (http://docs.python.org/dev/library/collections.html#collections.defau...)
> rather than a regular dictionary; this would make the
> count-incrementing part nicer.
>
> Taking these changes into account, your code becomes:
>
> from collections import defaultdict
>
> counts = defaultdict(lambda: 0)
>
> for filename in file_list:
> ? ? d = open(filename , "r")
> ? ? data = d.readlines()
> ? ? k = above_or_below(data) # This function seems to work correctly
> ? ? print "here is the value that was returned " , k
> ? ? counts[k] += 1
>
> ? ? values = counts.values()
> ? ? print "here is a list of the dictionary values ", values
> ? ? print "the length of the dictionary is ", len(counts)
>
> I don't immediately see what's causing your problem, but guess that it
> might've be related to the initialization of the `dict` variable.
>
> Cheers,
> Chris
> --http://blog.rebertia.com- Hide quoted text -
>
> - Show quoted text -

I initialized the dictionary earlier in the program like this -

  hashtable = {}

I changed the "dict" to hashtable but I still get the same result
I will try to learn about the defaultdict but I'm just trying to keep
it as simple as I can for now

Revised code

for x in range(len(file_list)):
	d = open(file_list[x] , "r")
	data = d.readlines()
	k = 0
	k = above_or_below(data)
	print "here is the value that was returned ",k
	hashtable[k] = hashtable.get(k,0) + 1


hashtable_list = hashtable.values()
print "here is a list of the dictionary values ", hashtable_list
print "the length of the dictionary is ", len(hashtable)

Output
# The first 3 lines are printed from the function
# right before the return statement.  This output
# snippet shows the last two stocks.  The function
# SAYS it is returning the correct value but only
# the last date seems to make it to the hashtable
Function will return k which = 11/11/2008
Function will return k which = 11/12/2008
Function will return k which = 11/14/2008

# this line is printed from the code above
# I don't understand why all three dates don't
# seem to make it to the main program.  Only
# the last date seems to be recognized
here is the value that was returned 11/14/2008

Function will return k which = 11/11/2008
Function will return k which = 11/12/2008
Function will return k which = 11/14/2008
here is the value that was returned 11/14/2008
here is a list of the dictionary values [5]
the length of the dictionary is 1
>Exit code: 0


From python at mrabarnett.plus.com  Mon Jul  6 19:41:53 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 00:41:53 +0100
Subject: Semi-Newbie needs a little help
In-Reply-To: <c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>	<mailman.2724.1246918979.8015.python-list@python.org>
	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
Message-ID: <4A528BC1.4040400@mrabarnett.plus.com>

Nile wrote:
[snip]
> I initialized the dictionary earlier in the program like this -
> 
>   hashtable = {}
> 
> I changed the "dict" to hashtable but I still get the same result
> I will try to learn about the defaultdict but I'm just trying to keep
> it as simple as I can for now
> 
> Revised code
> 
> for x in range(len(file_list)):
> 	d = open(file_list[x] , "r")
> 	data = d.readlines()

What's the point of the following line?

> 	k = 0
> 	k = above_or_below(data)
> 	print "here is the value that was returned ",k
> 	hashtable[k] = hashtable.get(k,0) + 1
> 
> 
> hashtable_list = hashtable.values()
> print "here is a list of the dictionary values ", hashtable_list
> print "the length of the dictionary is ", len(hashtable)
> 
> Output
> # The first 3 lines are printed from the function
> # right before the return statement.  This output
> # snippet shows the last two stocks.  The function
> # SAYS it is returning the correct value but only
> # the last date seems to make it to the hashtable

> Function will return k which = 11/11/2008
> Function will return k which = 11/12/2008
> Function will return k which = 11/14/2008
> 
> # this line is printed from the code above
> # I don't understand why all three dates don't
> # seem to make it to the main program.  Only
> # the last date seems to be recognized
> here is the value that was returned 11/14/2008
> 
> Function will return k which = 11/11/2008
> Function will return k which = 11/12/2008
> Function will return k which = 11/14/2008
> here is the value that was returned 11/14/2008
> here is a list of the dictionary values [5]
> the length of the dictionary is 1
>> Exit code: 0

I think there's a bug in 'above_or_below' which you haven't noticed.


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 19:49:40 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 20:49:40 -0300
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<MeqdnTn37r9N-s_XnZ2dnUVZ_jCdnZ2d@pdx.net>
Message-ID: <op.uwn642w7x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 18:15:44 -0300, Scott David Daniels  
<Scott.Daniels at acm.org> escribi?:

> brasse wrote:
>> I have been thinking about how write exception safe constructors in
>> Python. By exception safe I mean a constructor that does not leak
>> resources when an exception is raised within it.
> ...
>  > As you can see this is less than straight forward. Is there some kind
>  > of best practice that I'm not aware of?
>
> Not so tough.  Something like this tweaked version of your example:

Another variant: Presumably, there is already a method in Bar responsible  
for "normal" cleanup; just make sure it gets called (and write it in a  
robust way):

> class Foo(object):
>      def __init__(self, name, fail=False):
>          self.name = name
>          if not fail:
>              print '%s.__init__(%s)' % (type(self).__name__, name)
>          else:
>              print '%s.__init__(%s), FAIL' % (type(self).__name__, name)
>              raise ValueError('Asked to fail: %r' % fail)
>
>      def close(self):
>          print '%s.close(%s)' % (type(self).__name__, self.name)

class Bar(object):
     a = None # default values
     b = None

     def __init__(self):
         try:
             self.a = Foo('a')
             self.b = Foo('b', fail=True)
         except Exception, why:
             self.cleanup()
             raise

     def cleanup(self):
         if self.a is not None:
             self.a.close()
         if self.b is not None:
             self.b.close()

bar = Bar()

-- 
Gabriel Genellina



From mh at pixar.com  Mon Jul  6 20:21:32 2009
From: mh at pixar.com (mh at pixar.com)
Date: Tue, 07 Jul 2009 00:21:32 GMT
Subject: parsing times like "5 minutes ago"?
Message-ID: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>

I'm looking for something like Tcl's [clock scan] command which parses
human-readable time strings such as:

    % clock scan "5 minutes ago"
    1246925569
    % clock scan "tomorrow 12:00"
    1246993200
    % clock scan "today + 1 fortnight"
    1248135628

Does any such package exist for Python?

Many TIA!
Mark

-- 
Mark Harrison
Pixar Animation Studios


From pavlovevidence at gmail.com  Mon Jul  6 20:43:09 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 6 Jul 2009 17:43:09 -0700 (PDT)
Subject: parsing times like "5 minutes ago"?
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
Message-ID: <d7fea6e2-8f29-4fef-b482-631e83606ec7@q11g2000yqi.googlegroups.com>

On Jul 6, 5:21?pm, m... at pixar.com wrote:
> I'm looking for something like Tcl's [clock scan] command which parses
> human-readable time strings such as:
>
> ? ? % clock scan "5 minutes ago"
> ? ? 1246925569
> ? ? % clock scan "tomorrow 12:00"
> ? ? 1246993200
> ? ? % clock scan "today + 1 fortnight"
> ? ? 1248135628
>
> Does any such package exist for Python?

If you're on a machine with GNU datethe simplest solution is to use it
to parse the string.

Q&D:

def clock_scan(datestring):
    stdout,stderr = subprocess.Popen(
        ['date','+%s','--date=%s' % datestring ],
        stdout=subprocess.PIPE).communicate()
    return float(stdout)


clock_scan('1 hour ago')
clock_scan('next week')


Carl Banks


From rhodri at wildebst.demon.co.uk  Mon Jul  6 20:58:07 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 01:58:07 +0100
Subject: Semi-Newbie needs a little help
In-Reply-To: <c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2724.1246918979.8015.python-list@python.org>
	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
Message-ID: <op.uwoaa5yja8ncjz@gnudebst>

On Tue, 07 Jul 2009 00:29:36 +0100, Nile <nile_mcadams at yahoo.com> wrote:

> Revised code
>
> for x in range(len(file_list)):
> 	d = open(file_list[x] , "r")
> 	data = d.readlines()
> 	k = 0
> 	k = above_or_below(data)
> 	print "here is the value that was returned ",k
> 	hashtable[k] = hashtable.get(k,0) + 1
>
>
> hashtable_list = hashtable.values()
> print "here is a list of the dictionary values ", hashtable_list
> print "the length of the dictionary is ", len(hashtable)
>
> Output
> # The first 3 lines are printed from the function
> # right before the return statement.  This output
> # snippet shows the last two stocks.  The function
> # SAYS it is returning the correct value but only
> # the last date seems to make it to the hashtable
> Function will return k which = 11/11/2008
> Function will return k which = 11/12/2008
> Function will return k which = 11/14/2008

Have you checked the indentation of the print statement
that produces this?  Is it perhaps inside a loop still?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:01:44 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:01:44 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xk52p4tgg.fsf@ruckus.brouhaha.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
Message-ID: <006e795f$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:

> kj wrote:
>>  I've rewritten it like this:
>>
>>     sense = cmp(func(hi), func(lo))
>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>
>> Thanks for your feedback!
>>
>> kj
>>   
>>   
> As already said before, unlike other languages, sense in english does
> **not** mean direction. You should rewrite this part using a better
> name. Wrong informations are far worse than no information at all.

Absolutely.

>From Webster's Dictionary:

      8. (Geom.) One of two opposite directions in which a line,
      surface, or volume, may be supposed to be described by the
      motion of a point, line, or surface.
      [1913 Webster]


And from WordNet:

     2: the meaning of a word or expression; the way in which a word
        or expression or situation can be interpreted

Both meanings are relevant to the way KJ is using the word. Please take 
your own advice and stop giving wrong information. As a native English 
speaker, I had no difficulty understanding the meaning of "sense" in the 
sense intended by KJ.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:04:02 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:04:02 GMT
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
	<comdnVhXl4M6bczXnZ2dnUVZ_g2dnZ2d@pdx.net>
Message-ID: <006e79e9$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 05:47:18 -0700, Scott David Daniels wrote:

> Steven D'Aprano wrote:
>> ... That's the Wrong Way to do it --
>> you're using a screwdriver to hammer a nail....
> 
> Don't knock tool abuse (though I agree with you here). Sometimes tool
> abuse can produce good results.  For example, using hammers to drive
> screws for temporary strong holds led to making better nails.

Historically, nails were invented a long time before screws. Screws as 
fasteners weren't invented until the 1400s, nails were used thousands of 
years ago.

And hammering screws makes temporary *weak* holds, not strong, because 
the screw only touches the sides of the hole lightly. Unless the screw 
has been specifically designed to be hammered, hammering screws is pretty 
much the definition of incompetence and/or laziness!


-- 
Steven


From chris at simplistix.co.uk  Mon Jul  6 21:09:41 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 02:09:41 +0100
Subject: Where does setuptools live?
In-Reply-To: <3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
Message-ID: <4A52A055.8080108@simplistix.co.uk>

Floris Bruynooghe wrote:
> It is, see
> http://mail.python.org/pipermail/distutils-sig/2009-July/012374.html
> 
> 
>> It's seen no changes in 9 months.
> 
> It's setuptools...  I'm sure you can find many flamefests on distutils-
> sig about this.

Yeah, distutils-sig is the right place to discuss.

I wonder how close setuptools is to being forked because of Phil Eby's 
unwillingness to apply patches and/or clean up the horrible setuptools code?

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:16:41 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:16:41 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
Message-ID: <006e7ce0$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 16:43:43 +0100, Tim Rowe wrote:

> 2009/7/4 kj <no.email at please.post>:
> 
>> Precisely. ?As I've stated elsewhere, this is an internal helper
>> function, to be called only a few times under very well-specified
>> conditions. ?The assert statements checks that these conditions are as
>> intended. ?I.e. they are checks against the module writer's programming
>> errors.
> 
> Good for you. I'm convinced that you have used the assertion
> appropriately, and the fact that so many here are unable to see that
> looks to me like a good case for teaching the right use of assertions.
> For what it's worth, I read assertions at the beginning of a procedure
> as part of the specification of the procedure, and I use them there in
> order to document the procedure. An assertion in that position is for me
> a statement to the user of the procedure "it's your responsibility to
> make sure that you never call this procedure in such a way as to violate
> these conditions". They're part of a contract, as somebody (maybe you)
> pointed out.
> 
> As somebody who works in the safety-critical domain, it's refreshing to
> see somebody teaching students to think about the circumstances in which
> a procedure can legitimately be called. The hostility you've received to
> that idea is saddening, and indicative of why there's so much buggy
> software out there.

LOL.

Maybe the reason for "so much buggy software" is that people 
inappropriately use assert, thus changing the behaviour of code depending 
on whether it is run with the -O flag or not.

I don't know what "hostility" you're seeing. The only hostility I'm 
seeing is from the OP, which is bizarre considering that he asked for 
advice and we gave it. What I see is a bunch of people concerned that the 
OP is teaching novices a bad habit, namely, using assert for error 
checking. He claims -- angrily and over and over again -- that in his 
code, the assertions should never fail. Great. Good for him for knowing 
when to use assert. But are the novices going to learn that lesson, or 
will they simply learn "use assert for error checking"?



-- 
Steven


From davea at ieee.org  Mon Jul  6 21:18:57 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 21:18:57 -0400
Subject: Semi-Newbie needs a little help
In-Reply-To: <4A528BC1.4040400@mrabarnett.plus.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>	<mailman.2724.1246918979.8015.python-list@python.org>	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
	<4A528BC1.4040400@mrabarnett.plus.com>
Message-ID: <4A52A281.3040101@ieee.org>

MRAB wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Nile wrote:
> [snip]
>> I initialized the dictionary earlier in the program like this -
>>
>>   hashtable = {}
>>
>> I changed the "dict" to hashtable but I still get the same result
>> I will try to learn about the defaultdict but I'm just trying to keep
>> it as simple as I can for now
>>
>> Revised code
>>
>> for x in range(len(file_list)):
>>     d = open(file_list[x] , "r")
>>     data = d.readlines()
>
> What's the point of the following line?
>
>>     k = 0
>>     k = above_or_below(data)
>>     print "here is the value that was returned ",k
>>     hashtable[k] = hashtable.get(k,0) + 1
>>
>>
>> hashtable_list = hashtable.values()
>> print "here is a list of the dictionary values ", hashtable_list
>> print "the length of the dictionary is ", len(hashtable)
>>
>> Output
>> # The first 3 lines are printed from the function
>> # right before the return statement.  This output
>> # snippet shows the last two stocks.  The function
>> # SAYS it is returning the correct value but only
>> # the last date seems to make it to the hashtable
>
>> Function will return k which = 11/11/2008
>> Function will return k which = 11/12/2008
>> Function will return k which = 11/14/2008
>>
>> # this line is printed from the code above
>> # I don't understand why all three dates don't
>> # seem to make it to the main program.  Only
>> # the last date seems to be recognized
>> here is the value that was returned 11/14/2008
>>
>> Function will return k which = 11/11/2008
>> Function will return k which = 11/12/2008
>> Function will return k which = 11/14/2008
>> here is the value that was returned 11/14/2008
>> here is a list of the dictionary values [5]
>> the length of the dictionary is 1
>>> Exit code: 0
>
> I think there's a bug in 'above_or_below' which you haven't noticed.
>
> </div>
>
The code supplied doesn't match the output supplied.  It'd probably help 
if the output was actually pasted from the command window, instead of 
retyped with more comments than data.  And of course it'd help if you 
actually showed us the function above_or_below(), which is probably 
where the bug is.  If it prints three values, but returns a string, then 
why would you be surprised?   Maybe you intended it to return a list?

Each time above_or_below() it's called, it prints three lines before 
returning, but only returns the final value.  How big is file_list?  I 
suspect it's of length 5.

And the output is shown as repeated twice, but it probably was actually 
five sets of data.

You do know you can print hashtable, don't you?  You're extracting and 
printing the values, but not bothering with the keys.

I suggest you add a print to the entry point of above_or_below(), to 
match the one you have for its return.  And all of these print lines 
should be indented.  That might make it easier to interpret the output, 
without lots of inserted comments.

DaveA


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul  6 21:20:04 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 01:20:04 GMT
Subject: Newbie needs help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2732.1246922109.8015.python-list@python.org>
Message-ID: <006e7dac$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 17:00:39 -0600, nacim_bravo wrote:

> Dear Python gurus,
> 
> If I'd like to set dielectric constant for the certain material, is it
> possible to do such in Python environment? If yes, how to do or what
> syntax can be used?

certain_material.dielectric_constant = 1.234


> Also, I'd like to get a simulation result, like voltage, is it possible
> to get this value in Python environment?

Yes.



-- 
Steven


From ben.welsh at gmail.com  Mon Jul  6 21:25:13 2009
From: ben.welsh at gmail.com (palewire)
Date: Mon, 6 Jul 2009 18:25:13 -0700 (PDT)
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
Message-ID: <24365710.post@talk.nabble.com>



In my application, I'd like to have a function that compares two values,
either of which may be null, and then classify the result depending on
whether one is higher or lower than the other.

I find myself writing something clunky like this, and I'm curious whether
anyone might know a more elegant way for parsing this out.

def compare(a, b):
    if not a and not b:
        return "No data"
    else:
        if a == 0 and b == 0:
            return "Never had"
        else:
            if a == b:
                return "Stayed the same"
            elif a < b:
                return "Gained"
            elif a > b and b > 0:
                return "Lost Some"
            elif a > b and b == 0:
                return "Lost All"

If there's some obvious way to search for this solution online, feel free to
slap me with that. I tried digging around on Google and couldn't come up
with much.

Thanks much.
-- 
View this message in context: http://www.nabble.com/Looking-for-a-slick-way-to-classify-relationship-between-two-numbers%2C-without-tons-of-if-else-tp24365710p24365710.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From gherron at islandtraining.com  Mon Jul  6 21:29:51 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Mon, 06 Jul 2009 18:29:51 -0700
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
Message-ID: <4A52A50F.1060208@islandtraining.com>

nacim_bravo at agilent.com wrote:
> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment? 
>
> Please let me know, 
> nacim
>   
This would be a good place for you to start:
  http://www.catb.org/~esr/faqs/smart-questions.html


From ldo at geek-central.gen.new_zealand  Mon Jul  6 21:33:18 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 07 Jul 2009 13:33:18 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<fed60b17-c49e-4f9c-bcee-fbf5ea0cc840@r33g2000yqn.googlegroups.com>
	<mailman.2714.1246910113.8015.python-list@python.org>
Message-ID: <h2u8kv$hdf$2@lust.ihug.co.nz>

In message <mailman.2714.1246910113.8015.python-list at python.org>, Terry 
Reedy wrote:

> ... it is C, not Python, that is out of step with standard usage in math
> and most languages ...

And it is C that introduced "==" for equality, versus "=" for assignment, 
which Python slavishly followed instead of keeping "=" with its mathematical 
meaning and using ":=" for assignment.



From david.lyon at preisshare.net  Mon Jul  6 21:55:03 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Mon, 06 Jul 2009 21:55:03 -0400
Subject: Where does setuptools =?UTF-8?Q?live=3F?=
In-Reply-To: <4A52A055.8080108@simplistix.co.uk>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
Message-ID: <d7a4b1f129accf47d72f18aec329aea8@preisshare.net>

On Tue, 07 Jul 2009 02:09:41 +0100, Chris Withers <chris at simplistix.co.uk>
wrote:
> I wonder how close setuptools is to being forked because of Phil Eby's 
> unwillingness to apply patches and/or clean up the horrible setuptools
> code?

setuptools... as far as I can see isn't actually installed until you
install easyinstall...

Pip (http://pypi.python.org/pypi/pip) and enstall 
(http://pypi.python.org/pypi/Enstaller/3.1.0) seem to be forks of 
setuptools already...

So it looks like it's already been forked to some degree..

What hasn't happened is enough testing of pypi packages and installing
with setuptools/pip/enstall from pypi.

If the xmlrpc links actually "worked" on pypi...

http://wiki.python.org/moin/PyPiXmlRpc?action=show&redirect=CheeseShopXmlRpc

ie.. that they would allow a developer to download a packages via rpc....

then this whole issue could probably be fixed more easily...

ok - the process isn't perfect... 

but there's room for improvement...

David



From rhodri at wildebst.demon.co.uk  Mon Jul  6 22:11:43 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 07 Jul 2009 03:11:43 +0100
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
In-Reply-To: <24365710.post@talk.nabble.com>
References: <24365710.post@talk.nabble.com>
Message-ID: <op.uwodptt9a8ncjz@gnudebst>

On Tue, 07 Jul 2009 02:25:13 +0100, palewire <ben.welsh at gmail.com> wrote:

> In my application, I'd like to have a function that compares two values,
> either of which may be null, and then classify the result depending on
> whether one is higher or lower than the other.
>
> I find myself writing something clunky like this, and I'm curious whether
> anyone might know a more elegant way for parsing this out.

It depends on what you want to do with the information.  If you're doing
different things on each case, you might as well do it with an if-chain,
though you could make it a bit tidier:

> def compare(a, b):
>     if not a and not b:

Did you mean "if a is None or b is None:" here?

>         return "No data"
>     else:
>         if a == 0 and b == 0:

This will never fire, because it will always be
caught by the test above.

>             return "Never had"
>         else:
>             if a == b:
>                 return "Stayed the same"
>             elif a < b:
>                 return "Gained"
>             elif a > b and b > 0:
>                 return "Lost Some"
>             elif a > b and b == 0:
>                 return "Lost All"

def compare(a, b):
     if a is not None and b is not None:
	return "No data"
     elif a == 0 and b == 0:
         return "Never had"
     elif a == b:
         return "Stayed the same"
     elif a < b:
         return "Gained"
     elif b > 0:
         return "Lost Some"
     return "Lost All"


Alternatively you can do something like the (deprecated) cmp and a
dispatch table:

CMP_TABLE = [ "Gained", "Stayed the same", "Lost Some", "Lost All"]

def compare(a, b):
     if a is not None or b is not None:
         return "No data"
     c = cmp(a, b) + 1
     if c == 2 and b == 0:
         c = 3
     return CMP_TABLE[c]

There's no cmp() in Python 3.x so you'd have to roll your own.  At
that point you might as well revert to the if-chain, since it'll be
a lot easier to understand when you come back to it in six months
time.


-- 
Rhodri James *-* Wildebeest Herder to the Masses


From gagsl-py2 at yahoo.com.ar  Mon Jul  6 22:18:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 06 Jul 2009 23:18:37 -0300
Subject: Python Error from Apress book
References: <24364269.post@talk.nabble.com>
Message-ID: <op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com> escribi?:

> When I try to run the command as outlined in
> the book "simple_markup2.py < test_input.txt > test_output.html i get the
> following error every time.
>
> IOError: [Errno 9] Bad file descriptor

That's a Windows problem. When you execute the script as itself (either as  
you do in the command line, or by double-clicking on it), it doesn't have  
valid standard handles.
You have to invoke Python explicitely:

python simple_markup2.py < test_input.txt > test_output.html

(you may need to specify the full path to python.exe, or add the directory  
where Python is installed to your system PATH).

-- 
Gabriel Genellina



From fetchinson at googlemail.com  Mon Jul  6 22:48:39 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Mon, 6 Jul 2009 19:48:39 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <006da5a2$0$9711$c3e8da3@news.astraweb.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>

>>>> I wonder how many people have been tripped up by the fact that
>>>>
>>>>     ++n
>>>>
>>>> and
>>>>
>>>>     --n
>>>>
>>>> fail silently for numeric-valued n.
>>>
>>> What do you mean, "fail silently"? They do exactly what you should
>>> expect:
>>>>>> ++5  # positive of a positive number is positive
>>>
>>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>>> that are buggy, not Python.
>>
>> Well, those expectations are taken seriously when new features are
>> introduced into the language - and sometimes the feature is dismissed
>> just because it would be confusing for some. If a += 1 works, expecting
>> ++a to have the same meaning is very reasonable (for those coming from
>> languages with a ++ operator, like C or Java) - more when ++a is a
>> perfectly valid expression. If this issue isn't listed under the various
>> "Python gotchas" articles, it should...
>
> The fact that it isn't suggests strongly to me that it isn't that common
> a surprise even for Java and C programmers. This is the first time I've
> seen anyone raise it as an issue.
>
> There are plenty of other languages other than Java and C. If we start
> listing every feature of Python that's different from some other
> language, we'll never end.

Yes, there are plenty of languages other than Java and C, but the
influence of C is admittedly huge in Python. Why do you think loops
are called "for", conditionals "if" or "while", functions return via
"return", loops terminate via "break" and keep going via "continue"
and why is comparison written as "==", etc, etc? All of these are
coming from C (or an even earlier language) and my point is that users
are most of time correct when they assume that something will work the
same way as in C.

So I'd think that putting a warning in a FAQ or a Python Gotchas list
about ++n would be very useful for many users. And it does not imply
that the differences from every other language should be documented in
a similar fashion. Only C :)

Cheers,
Daniel

> For what it's worth, Ruby appears to behave the same as Python:
>
> $ irb
> irb(main):001:0> n = 5
> => 5
> irb(main):002:0> ++n
> => 5
> irb(main):003:0> --n
> => 5
> irb(main):004:0> -+n
> => -5
>


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From astan.chee at al.com.au  Mon Jul  6 22:58:24 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 7 Jul 2009 12:58:24 +1000
Subject: copytree with timeout in windows
Message-ID: <4A52B9D0.9040608@al.com.au>

Hi,
I'm trying to modify the copytree function in shutil so that any file 
being copied does not take more than 5 minutes (if it does, skip to the 
next one). This is what I have so far:

import shutil
import signal, os

def handler(signum, frame):
    print 'Signal handler called with signal', signum
    raise IOError, "Couldn't open device!"

signal.signal(signal.SIGALRM, handler)

def copytree(src, dst):
    names = os.listdir(src)
    os.makedirs(dst)
    signal.alarm(0)
    for name in names:
        if name in ignored_names:
            continue
        srcname = os.path.join(src, name)
        dstname = os.path.join(dst, name)
        try:
            if os.path.isdir(srcname):
                copytree(srcname, dstname, symlinks, ignore)
            else:
                signal.alarm(300)
                shutil.copy2(srcname, dstname)
        except (IOError, os.error), why:
            print str(why)
        # catch the Error from the recursive copytree so that we can
        # continue with other files
        except Error, err:
            print str(err.args[0])

source = "c:\\testwa\\"
destination = "d:\\testwa\\"

copytree(source,destination)

Then I re-read the documentation which said that signal.SIGALRM is 
unix/linux only. How do I go about doing this in windows?
Thanks for any help.
Cheers
Astan




From rocky at gnu.org  Mon Jul  6 23:13:09 2009
From: rocky at gnu.org (rocky)
Date: Mon, 6 Jul 2009 20:13:09 -0700 (PDT)
Subject: module name versus function name resolution conflict.
Message-ID: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>

Someone recently reported a problem in pydb where a function defined
in his program was conflicting with a module name that pydb uses. I
think I understand what's wrong, but I don't have any elegant
solutions to the problem. Suggestions would be appreciated.

In a nutshell, here's the problem:

In file fns:

  def foo(): print "foo"

In file pdebug.py:

  import fns, sys

  def trace_dispatch(frame, event, arg):
      fns.foo()
      print frame, event, arg
      return trace_dispatch

  sys.settrace(trace_dispatch)
  execfile('myprogram.py')

Finally file myprogram.py:

  def fns(): print "This is the *other* fns"

When you run pdebug.py you get:

$ python pdebug.py
foo
<frame object at 0xdd9030> call None
foo
<frame object at 0xdd9030> line None
Traceback (most recent call last):
  File "pdebug.py", line 7, in <module>
    execfile('myprogram.py')
  File "myprogram.py", line 1, in <module>
    def fns(): print "This is the *other* fns"
  File "pdebug.py", line 3, in trace_dispatch
    fns.foo()
AttributeError: 'function' object has no attribute 'foo'


Basically inside the trace hook, local functions are visible and take
precedence over (global) module names. I could move "import fns"
inside trace_dispatch(), but I'd have to do that in all of the methods
that module "fns" is used.  Also note that using the form:
  from fns import foo

would eliminate the conflict on "fns", but I'd still have potential
conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
reduce the chance of a conflict but not eliminate it.

Suggestions?




From davea at ieee.org  Mon Jul  6 23:28:39 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 06 Jul 2009 23:28:39 -0400
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
In-Reply-To: <24365710.post@talk.nabble.com>
References: <24365710.post@talk.nabble.com>
Message-ID: <4A52C0E7.9060502@ieee.org>

palewire wrote:
> In my application, I'd like to have a function that compares two values,
> either of which may be null, and then classify the result depending on
> whether one is higher or lower than the other.
>
> I find myself writing something clunky like this, and I'm curious whether
> anyone might know a more elegant way for parsing this out.
>
> def compare(a, b):
>     if not a and not b:
>         return "No data"
>     else:
>         if a == 0 and b == 0:
>             return "Never had"
>         else:
>             if a == b:
>                 return "Stayed the same"
>             elif a < b:
>                 return "Gained"
>             elif a > b and b > 0:
>                 return "Lost Some"
>             elif a > b and b == 0:
>                 return "Lost All"
>
> If there's some obvious way to search for this solution online, feel free to
> slap me with that. I tried digging around on Google and couldn't come up
> with much.
>
> Thanks much.
>   
Before one can "optimize" a function, one needs to get the function 
correct.  Looks to me that if a and b are both zero, it'll say "No data" 
and never get to the "Never had" test.  And if a is positive and b is 
None, it'll return None, rather than any string.

Anyway, any "optimized" construct is going to be nearly as big as this.  
You'd have to define a list of strings, and then compute an index value 
that gave you the appropriate value.  While I could probably come up 
with such, I hardly think it's worthwhile.  The cases are confusing 
enough to me that I'd not want to make the code any less readable by 
some formula & lookup.

That brings us to the question of what is more elegant.  To me the 
elegant code is readable first, and efficient (space & time) second.  I 
suspect efficiency would be nearly optimal by careful ordering of the 
nested ifs.  Find the most likely cases, and test for them first.

If this is a programming puzzle, for entertainment purposes, here's the 
way I'd tackle making it "efficient" obfuscated code.  Start by checking 
if either value is None.  Something like:

table = ("Lost Some","Lost All","Gained","Gained","Stayed the 
same","Never had, never will")
def compare2(a,b):
    global table
    if a is None or b is None:
        return "Invalid data"
    return table[4*(a==b)+2*(a<b)+(b==0)]

davea


From lasleyse at gmail.com  Mon Jul  6 23:48:36 2009
From: lasleyse at gmail.com (selasley)
Date: Mon, 6 Jul 2009 20:48:36 -0700 (PDT)
Subject: parsing times like "5 minutes ago"?
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
	<d7fea6e2-8f29-4fef-b482-631e83606ec7@q11g2000yqi.googlegroups.com>
Message-ID: <c7bcb0bd-e09d-4aea-8633-249f1e36e183@i6g2000yqj.googlegroups.com>

On Jul 6, 8:43?pm, Carl Banks <pavlovevide... at gmail.com> wrote:
> On Jul 6, 5:21?pm, m... at pixar.com wrote:
>
> > I'm looking for something like Tcl's [clock scan] command which parses
> > human-readable time strings such as:
>
> > ? ? % clock scan "5 minutes ago"
> > ? ? 1246925569
> > ? ? % clock scan "tomorrow 12:00"
> > ? ? 1246993200
> > ? ? % clock scan "today + 1 fortnight"
> > ? ? 1248135628
>
> > Does any such package exist for Python?
>
> If you're on a machine with GNU datethe simplest solution is to use it
> to parse the string.
>
> Q&D:
>
> def clock_scan(datestring):
> ? ? stdout,stderr = subprocess.Popen(
> ? ? ? ? ['date','+%s','--date=%s' % datestring ],
> ? ? ? ? stdout=subprocess.PIPE).communicate()
> ? ? return float(stdout)
>
> clock_scan('1 hour ago')
> clock_scan('next week')
>
> Carl Banks

The timelib module might do what you want
http://pypi.python.org/pypi/timelib/0.2


From tjreedy at udel.edu  Mon Jul  6 23:50:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 06 Jul 2009 23:50:08 -0400
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <h2uglg$u9e$1@ger.gmane.org>

kj wrote:

> "There is real value in having a small language."
> 
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
> 
> So there.

small != minimal

> 
> BTW, that's just one example.  I've seen similar sentiments expressed
> by Guido over and over and over: any new proposed enhancement to
> Python must be good enough in his mind to justify cluttering the
> language.  That attitude counts as minimalism in my book.
> 
> The best explanation I have found so far for re.match is that it
> is an unfortunate bit of legacy, something that would not be there
> if the design of Python did not have to be mindful of keeping old
> code chugging along...

It is possible that someone proposed removing re.match for 3.0, but I do 
not remember any such discussion. Some things were dropped when that 
contraint was (teporarily) dropped.

tjr



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 23:51:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 00:51:07 -0300
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<50697b2c0907061522o59bf5333qec3722039e688426@mail.gmail.com>
	<4A527F85.7030400@mrabarnett.plus.com>
Message-ID: <op.uwn8nnvnx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 19:49:41 -0300, MRAB <python at mrabarnett.plus.com>
escribi?:
> Chris Rebert wrote:

>>  from collections import defaultdict
>>  counts = defaultdict(lambda: 0)
>>
> Better is:
> counts = defaultdict(int)

For speed? This is even faster:
zerogen = itertools.repeat(0).next
counts = defaultdict(zerogen)

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul  6 23:51:09 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 00:51:09 -0300
Subject: How to map size_t using ctypes?
References: <mailman.2691.1246888326.8015.python-list@python.org>
	<7belo1F21fs3vU1@mid.uni-berlin.de>
	<DB4ED723-C8DD-492F-A7CC-B3CE14F8B723@semanchuk.com>
Message-ID: <op.uwn9hrmpx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 06 Jul 2009 13:29:21 -0300, Philip Semanchuk
<philip at semanchuk.com> escribi?:
> On Jul 6, 2009, at 12:10 PM, Diez B. Roggisch wrote:
>> Philip Semanchuk wrote:
>>
>>> I can't figure out how to map a C variable of size_t via Python's
>>> ctypes module.
>>
>> from ctypes import c_size_t
>
> D'oh! [slaps forehead]
>
> That will teach me to RTFM. [...] You'd be surprised at the amount of  
> Googling I did without learning this on my own.

Yep, seems like these terms in particular are hard to find. Searching for
+ctypes +size_t, the first "good" result comes only at page 3. Bad luck...
:(

-- 
Gabriel Genellina



From aahz at pythoncraft.com  Tue Jul  7 00:02:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 6 Jul 2009 21:02:19 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <h2uhcb$blq$1@panix3.panix.com>

In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>,
Steven D'Aprano  <steve at REMOVE-THIS-cybersource.com.au> wrote:
>On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>> kj wrote:
>>>
>>>     sense = cmp(func(hi), func(lo))
>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>
>> As already said before, unlike other languages, sense in english does
>> **not** mean direction. You should rewrite this part using a better
>> name. Wrong informations are far worse than no information at all.
>
>Absolutely.
>
>From Webster's Dictionary:
>
>      8. (Geom.) One of two opposite directions in which a line,
>      surface, or volume, may be supposed to be described by the
>      motion of a point, line, or surface.
>      [1913 Webster]
>
>
>And from WordNet:
>
>     2: the meaning of a word or expression; the way in which a word
>        or expression or situation can be interpreted
>
>Both meanings are relevant to the way KJ is using the word. Please take 
>your own advice and stop giving wrong information. As a native English 
>speaker, I had no difficulty understanding the meaning of "sense" in the 
>sense intended by KJ.

As another native English speaker, I agree with Jean-Michel; this is the
first time I've seen "sense" used to mean direction.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From mail at timgolden.me.uk  Tue Jul  7 00:11:30 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Tue, 07 Jul 2009 05:11:30 +0100
Subject: copytree with timeout in windows
In-Reply-To: <4A52B9D0.9040608@al.com.au>
References: <4A52B9D0.9040608@al.com.au>
Message-ID: <4A52CAF2.7010707@timgolden.me.uk>

Astan Chee wrote:
> Hi,
> I'm trying to modify the copytree function in shutil so that any file 
> being copied does not take more than 5 minutes (if it does, skip to the 
> next one). 

One suggestion is to use the CopyFileEx API
exposed in the win32file module from pywin32. That
allows for a callback function which can abort
the copy (or issue a progress meter, etc.).

Obviously, you'd have to roll your own copytree, but
that's not beyond the wit of man.

TJG


From me at haolian.org  Tue Jul  7 00:38:10 2009
From: me at haolian.org (Hao Lian)
Date: Tue, 07 Jul 2009 00:38:10 -0400
Subject: a little wsgi framework
In-Reply-To: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
References: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
Message-ID: <6a368$4a52d120$a652c80b$16349@ALLTEL.NET>

timmyt wrote:
> i'm interested in getting opinions on a small wsgi framework i
> assembled from webob, sqlalchemy, genshi, and various code fragments i
> found on the inter-tubes
> 
> here is the interesting glue - any comments / suggestions would be
> much appreciated

Fun! Since you're already using WebOb, you should
give webob.Response a try, which will handle your
headers in a sexier way. (If you start using
paste.httpexceptions and the middleware, you can
avoid manually sending headers altogether.)

http://pythonpaste.org/webob/reference.html#response-as-a-wsgi-application
http://pythonpaste.org/modules/httpexceptions.html#paste.httpexceptions.HTTPExceptionHandler

timmyt wrote:
>             global config
> 
>             try:
>                 return_dict = target(request, start_response)
>                 return_string = template.generate(**return_dict).render
> (method)
>                 config['database.Session'].commit()
>             except:
>                 config['database.Session'].rollback()
>                 raise
>             finally:
>                 config['database.Session'].remove()

The config global probably isn't thread-safe
depending on what you're doing with the
application. A safer way to go would be use Paste
Registry like Pylons does with its globals or just
attach it to Request.

http://pythonpaste.org/webob/reference.html#ad-hoc-attributes



From lie.1296 at gmail.com  Tue Jul  7 00:51:51 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 04:51:51 GMT
Subject: A Bug By Any Other Name ...
In-Reply-To: <mailman.2677.1246869173.8015.python-list@python.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>	<4A519AC0.1050905@islandtraining.com>	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>	<mailman.2674.1246866966.8015.python-list@python.org>	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
Message-ID: <HvA4m.3141$ze1.109@news-server.bigpond.net.au>

Chris Rebert wrote:
> On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
> D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
>> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim Golden
>> wrote:
>>
>>> The difficulty here is knowing where to put such a warning.
>>> You obviously can't put it against the "++" operator as such
>>> because... there isn't one.
>> This bug is an epiphenomenon. :)
> 
> Well, like I suggested, it /could/ be made an operator (or rather, a
> lexer token) which just causes a compile/parse error.
> 
> Cheers,
> Chris

There are edge cases (level: very rare) where you legitimately want to
actually do that, e.g.:

class A(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return B(self)
    def __neg__(self):
        return D(self)

class B(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return C(self)
    def __neg__(self):
        return A(self)

class C(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return D(self)
    def __neg__(self):
        return B(self)

class D(object):
    def __init__(self, arg):
        self.value = arg.value
    def __pos__(self):
        return A(self)
    def __neg__(self):
        return C(self)

def cons(val):
    class E(object):
        value = val
    return E()

>>> a = A(cons(10))
>>> +a
<__main__.B object at 0x7fbf723c8690>
>>> ++a
<__main__.C object at 0x7fbf723c8710>
>>> +++a
<__main__.D object at 0x7fbf723c8710>
>>> --a
<__main__.C object at 0x7fbf723c8710>


From fetchinson at googlemail.com  Tue Jul  7 00:52:40 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Mon, 6 Jul 2009 21:52:40 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2ujrs$4c0$1@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
Message-ID: <fbe2e2100907062152u62d84480k63e6e41206df8fce@mail.gmail.com>

>> Yes, there are plenty of languages other than Java and C, but the
>> influence of C is admittedly huge in Python. Why do you think loops
>> are called "for", conditionals "if" or "while", functions return via
>> "return", loops terminate via "break" and keep going via "continue"
>> and why is comparison written as "==", etc, etc? All of these are
>> coming from C (or an even earlier language) and my point is that users
>
> 	for, if, and return were common keywords in FORTRAN.
>
> 	Not to mention BASIC
>
> 	Both of which predate C

Yes, hence my comment above, ".... coming from C (or an even earlier
language) ......".

Cheers,
Daniel


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:05:12 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:05:12 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
Message-ID: <006eb26f$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 21:02:19 -0700, Aahz wrote:

> In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>, Steven D'Aprano 
> <steve at REMOVE-THIS-cybersource.com.au> wrote:
>>On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>>> kj wrote:
>>>>
>>>>     sense = cmp(func(hi), func(lo))
>>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>>
>>> As already said before, unlike other languages, sense in english does
>>> **not** mean direction. You should rewrite this part using a better
>>> name. Wrong informations are far worse than no information at all.
>>
>>Absolutely.
>>
>>From Webster's Dictionary:
>>
>>      8. (Geom.) One of two opposite directions in which a line,
>>      surface, or volume, may be supposed to be described by the motion
>>      of a point, line, or surface.
>>      [1913 Webster]
>>
>>
>>And from WordNet:
>>
>>     2: the meaning of a word or expression; the way in which a word
>>        or expression or situation can be interpreted
>>
>>Both meanings are relevant to the way KJ is using the word. Please take
>>your own advice and stop giving wrong information. As a native English
>>speaker, I had no difficulty understanding the meaning of "sense" in the
>>sense intended by KJ.
> 
> As another native English speaker, I agree with Jean-Michel; this is the
> first time I've seen "sense" used to mean direction.


Just goes to show you learn something new all the time.

http://www.merriam-webster.com/dictionary/sense

    7: one of two opposite directions especially of motion (as 
    of a point, line, or surface)


http://dictionary.reference.com/browse/sense

    18.  Mathematics. one of two opposite directions in which 
    a vector may point.



Paraphrasing the Collins Dictionary of Mathematics:

The sense of a vector is the sign of the measure, contrasted with the 
magnitude. Thus the vectors AB and BA have the same direction but 
opposite sense. Sense is also used to distinguish clockwise and anti-
clockwise.

Sense is, if you like, a "signed direction". "Towards north" (say) as 
opposed to "along the north-south axis".



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:07:08 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:07:08 GMT
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <006eb2e3$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 15:02:26 -0700, Michael Mossey wrote:

> On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>>
>> > What is required in a python program to make sure it catches a
>> > control-
>> > c on the command-line? Do some i/o? The OS here is Linux.
>>
>> You can use a try/except to catch a KeyboardInterrupt exception, or you
>> can trap it using the signal
>> module:http://docs.python.org/library/signal.html
>>
>> You want to trap SIGINT.
>>
>> HTH
>> Philip
> 
> Thanks to both of you. However, my question is also about whether I need
> to be doing i/o or some similar operation for my program to notice in
> any shape or form that Control-C has been pressed. In the past, I've
> written Python programs that go about their business ignoring Ctrl-C.

I bet that somewhere in your code you have something like:


for x in really_big_list:
    try:
        long_running_process(x)
    except:
        continue


If that's what you're doing, stop! The correct way is:


for x in really_big_list:
    try:
        long_running_process(x)
    except Exception:
        # Let KeyboardInterrupt and SystemExit through.
        continue


or even:

for x in really_big_list:
    try:
        long_running_process(x)
    except (KeyboardInterrupt, SystemExit):
        print "User requested exit... shutting down now"
        cleanup()
        raise
    except Exception:
        continue



-- 
Steven


From lie.1296 at gmail.com  Tue Jul  7 01:13:28 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 05:13:28 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h2uhcb$blq$1@panix3.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
Message-ID: <YPA4m.3147$ze1.970@news-server.bigpond.net.au>

Aahz wrote:
> In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>,
> Steven D'Aprano  <steve at REMOVE-THIS-cybersource.com.au> wrote:
>> On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>>> kj wrote:
>>>>     sense = cmp(func(hi), func(lo))
>>>>     assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>> As already said before, unlike other languages, sense in english does
>>> **not** mean direction. You should rewrite this part using a better
>>> name. Wrong informations are far worse than no information at all.
>> Absolutely.
>>
>>From Webster's Dictionary:
>>      8. (Geom.) One of two opposite directions in which a line,
>>      surface, or volume, may be supposed to be described by the
>>      motion of a point, line, or surface.
>>      [1913 Webster]
>>
>>
>> And from WordNet:
>>
>>     2: the meaning of a word or expression; the way in which a word
>>        or expression or situation can be interpreted
>>
>> Both meanings are relevant to the way KJ is using the word. Please take 
>> your own advice and stop giving wrong information. As a native English 
>> speaker, I had no difficulty understanding the meaning of "sense" in the 
>> sense intended by KJ.
> 
> As another native English speaker, I agree with Jean-Michel; this is the
> first time I've seen "sense" used to mean direction.

When people are fighting over things like `sense`, although sense may
not be strictly wrong dictionary-wise, it smells of something burning...


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:13:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:13:30 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
Message-ID: <006eb461$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 04:51:51 +0000, Lie Ryan wrote:

> Chris Rebert wrote:
>> On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
>> D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
>>> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim
>>> Golden wrote:
>>>
>>>> The difficulty here is knowing where to put such a warning. You
>>>> obviously can't put it against the "++" operator as such because...
>>>> there isn't one.
>>> This bug is an epiphenomenon. :)
>> 
>> Well, like I suggested, it /could/ be made an operator (or rather, a
>> lexer token) which just causes a compile/parse error.
>> 
>> Cheers,
>> Chris
> 
> There are edge cases (level: very rare) where you legitimately want to
> actually do that, e.g.:

Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.


Help on method __pos__ in module decimal:

__pos__(self, context=None) unbound decimal.Decimal method
    Returns a copy, unless it is a sNaN.

    Rounds the number (if more then precision digits)



-- 
Steven


From casevh at gmail.com  Tue Jul  7 01:16:39 2009
From: casevh at gmail.com (casevh)
Date: Mon, 6 Jul 2009 22:16:39 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org>
Message-ID: <c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com>

I discovered a serious bug with comparisons and have posted alpha2
which fixes that bug and adds Unicode support for Python 2.x

casevh


From clp2 at rebertia.com  Tue Jul  7 01:18:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 6 Jul 2009 22:18:20 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <006eb461$0$9711$c3e8da3@news.astraweb.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
	<006eb461$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <50697b2c0907062218t34c011ecna831de8aa441d8e1@mail.gmail.com>

On Mon, Jul 6, 2009 at 10:13 PM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Tue, 07 Jul 2009 04:51:51 +0000, Lie Ryan wrote:
>
>> Chris Rebert wrote:
>>> On Mon, Jul 6, 2009 at 1:29 AM, Lawrence
>>> D'Oliveiro<ldo at geek-central.gen.new_zealand> wrote:
>>>> In message <mailman.2674.1246866966.8015.python-list at python.org>, Tim
>>>> Golden wrote:
>>>>
>>>>> The difficulty here is knowing where to put such a warning. You
>>>>> obviously can't put it against the "++" operator as such because...
>>>>> there isn't one.
>>>> This bug is an epiphenomenon. :)
>>>
>>> Well, like I suggested, it /could/ be made an operator (or rather, a
>>> lexer token) which just causes a compile/parse error.
>>>
>>> Cheers,
>>> Chris
>>
>> There are edge cases (level: very rare) where you legitimately want to
>> actually do that, e.g.:
>
> Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.
>
>
> Help on method __pos__ in module decimal:
>
> __pos__(self, context=None) unbound decimal.Decimal method
> ? ?Returns a copy, unless it is a sNaN.
>
> ? ?Rounds the number (if more then precision digits)

Well, yes, but when would you apply it twice in a row?

(Not that I strongly support the prohibition idea, just thought it
should be brought up)

Cheers,
Chris
-- 
http://blog.rebertia.com


From mensanator at aol.com  Tue Jul  7 01:47:21 2009
From: mensanator at aol.com (Mensanator)
Date: Mon, 6 Jul 2009 22:47:21 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com>
Message-ID: <fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com>

On Jul 7, 12:16?am, casevh <cas... at gmail.com> wrote:
> I discovered a serious bug with comparisons and have posted alpha2
> which fixes that bug and adds Unicode support for Python 2.x
>
> casevh

Damn! I was just congatulating myself for pulling off
a hat trick (there had been no point in downloading
3.x without gmpy so I have been putting it off):

- installing Python 3.1
- installing gmpy 1.10
- converting my Collatz Function library to 3.1 syntax

And it all worked smoothly, just had to add parentheses
to my print statements, change xrange to range and all
my / to // (the library is exclusively integer). I had
gmpy running in my library on 3.1 in about 10 minutes.

So I'll have to re-do the gmpy install. Shouldn't be
any big deal.

I started doing some real world tests. Generally, things
look good (nothing crashes, timing looks not bad) but
I'm getting some funny results on one of my tests, so
I'll report back when I have more information.


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 01:57:14 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 05:57:14 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
Message-ID: <006ebea2$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:

> When people are fighting over things like `sense`, although sense may
> not be strictly wrong dictionary-wise, it smells of something burning...

That would be my patience.

I can't believe the direction this discussion has taken. Anybody sensible 
would be saying "Oh wow, I've just learned a new meaning to the word, 
that's great, I'm now less ignorant than I was a minute ago". But oh no, 
we mustn't use a standard meaning to a word, heaven forbid we disturb 
people's ignorance by teaching them something new.

It's as simple as this: using `sense` as a variable name to record the 
sense of a function is not a code smell, any more than using `flag` to 
record a flag would be, or `sign` to record the sign of an object. If you 
don't know the appropriate meanings of the words sense, flag or sign, 
learn them, don't dumb down my language.


-- 
Steven


From nomail at thank.you  Tue Jul  7 02:01:39 2009
From: nomail at thank.you (jack catcher (nick))
Date: Tue, 07 Jul 2009 09:01:39 +0300
Subject: Python and webcam capture delay?
In-Reply-To: <pan.2009.07.06.19.41.52.828000@nowhere.com>
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
Message-ID: <6xB4m.21104$vi5.8567@uutiset.elisa.fi>

Nobody kirjoitti:
> On Mon, 06 Jul 2009 20:41:03 +0300, jack catcher (nick) wrote:
> 
>>> Does the webcam just deliver frames, or are you getting frames out of
>>> a decoder layer?  If it's the latter, you want to distribute the encoded
>>> video, which should be much lower bandwidth.  Exactly how you do that
>>> depends a bit on what format the webcam claims to deliver.
>> Well, getting already encoded video from the webcam sounds almost like a 
>> free lunch (which it probably is not). At least I wouldn't want to get 
>> too long a delay because of the encoding.
>>
>> I haven't got the webcam(s) yet, and I guess I can basically purchase 
>> any ones I find suitable for getting the job done. Any recommendations?
> 
> The webcam is bound to do some encoding; most of them use USB "full speed"
> (12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.
> 
> Chroma subsampling and JPEG compression will both reduce the bandwidth
> without introducing noticable latency (the compression time will be no
> more than one frame).
> 
> Temporal compression will reduce the bandwidth further. Using B-frames
> (frames which contain the differences from a predicted frame which is
> based upon both previous and subsequent frames) will provide more 
> compression, but increases the latency significantly. For this reason, the
> compression built into video cameras normally only uses P-frames (frames
> which contain the differences from a predicted frame which is based only
> upon previous frames).
> 
> The biggest issue is likely to be finding latency specifications, followed
> by finding a camera which meets your latency requirement.

Thanks for the comments. Unfortunately, such specifications aren't easy 
to find, even in reviews. Fortunately several newer webcams seem at 
least to use usb2.

Regarding Python, I'll have to check whether the ImageCapture extension 
works at all, as someone suggested earlier, and the possibility of using 
DirectShow. I'm still considering Matlab as an option for Python here.


From ptmcg at austin.rr.com  Tue Jul  7 02:02:44 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Mon, 6 Jul 2009 23:02:44 -0700 (PDT)
Subject: parsing times like "5 minutes ago"?
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
Message-ID: <90911ef7-ff17-4aa0-9816-4579a638db92@j32g2000yqh.googlegroups.com>

On Jul 6, 7:21?pm, m... at pixar.com wrote:
> I'm looking for something like Tcl's [clock scan] command which parses
> human-readable time strings such as:
>
> ? ? % clock scan "5 minutes ago"
> ? ? 1246925569
> ? ? % clock scan "tomorrow 12:00"
> ? ? 1246993200
> ? ? % clock scan "today + 1 fortnight"
> ? ? 1248135628
>
> Does any such package exist for Python?
>
> Many TIA!
> Mark
>
> --
> Mark Harrison
> Pixar Animation Studios

I've been dabbling with such a parser with pyparsing - here is my
progress so far: http://pyparsing.wikispaces.com/UnderDevelopment

It parses these test cases:

today
tomorrow
yesterday
in a couple of days
a couple of days from now
a couple of days from today
in a day
3 days ago
3 days from now
a day ago
now
10 minutes ago
10 minutes from now
in 10 minutes
in a minute
in a couple of minutes
20 seconds ago
in 30 seconds
20 seconds before noon
20 seconds before noon tomorrow
noon
midnight
noon tomorrow


-- Paul


From wsysdu at gmail.com  Tue Jul  7 02:06:13 2009
From: wsysdu at gmail.com (Eric Wong)
Date: Tue, 07 Jul 2009 14:06:13 +0800
Subject: why PyObject_VAR_HEAD?
References: <d9c79d1e-3c30-44c5-8c1b-2378b3239b53@t21g2000yqi.googlegroups.com>
Message-ID: <h2uol6$eep$1@aioe.org>

kio wrote:

> Hi,
> 
> I'm studying the CPython source code. I don?t quite understand why
> they?re using PyObject_VAR_HEAD to define struct like PyListObject. 
To
> define such kind of struct, could I use _PyObject_HEAD_EXTRA as a
> header and add "items" pointer and "allocated" count explicity? Is
> there any difference?
> 
> Thanks.
> 
> Eric

first, _PyObject_HEAD_EXTRA is only useful for debug and defined as:
#ifdef Py_TRACE_REFS
   #define _PyObject_HEAD_EXTRA 	\
      struct _object *_ob_next;   \
      struct _object *_ob_prev;
   #define _PyObject_EXTRA_INIT 0, 0,
#else 
   #define _PyObject_HEAD_EXTRA
   #define _PyObject_EXTRA_INIT
#endif

and PyObject_HEAD is defined as
#define PyObject_HEAD    \
   _PyObject_HEAD_EXTRA  \
   int ob_refcnt;        \
   struct _typeobject *ob_type;

PyObject_VAR_HEAD defined as
#define PyObject_VAR_HEAD   \
   PyObject_HEAD            \
   int ob_size;

so you can see the differences between them here.
PyListObject is defined as
typedef struct{
    PyObject_VAR_HEAD
    PyObject **ob_item;
    int allocated;
}PyListObject;

After unfolding these macros we can get
typedef struct{
    _PyObject_HEAD_EXTRA
    int ob_refcnt;
    struct _typeobject *ob_type;
    int ob_size;
    PyObject **ob_item;
    int allocated;
}PyListObject;

So, if we don't use macros, we have to specify not only the "item" and 
"allocated", but also the ref count and type information of the object 
and the size info for a variable object. These information is not only 
used by PyListObject, but also PyStringObject and PyDictObject, so 
macros make it convenient and consize. 




From rogerb at rogerbinns.com  Tue Jul  7 02:16:10 2009
From: rogerb at rogerbinns.com (Roger Binns)
Date: Mon, 06 Jul 2009 23:16:10 -0700
Subject: Opening a SQLite database in readonly mode
In-Reply-To: <h2tnpp$6if$1@ger.gmane.org>
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org>
Message-ID: <h2up7a$epu$1@ger.gmane.org>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Joshua Kugler wrote:
> BTW, APSW is written by the same author as pysqlite.

Not even remotely true :-)  pysqlite was written by various people, with
the maintainer of the last several years being Gerhard H?ring.  I am the
(sole) author of APSW and have not contributed any code to pysqlite
although ideas have flowed freely between the projects and we share a
mailing list.

I started APSW in late 2004 because I wanted to use SQLite from Python
rather than using a layer that pretended SQLite was like other
databases.  There were various quirks of pysqlite I also didn't like
(many since corrected) and so scratched my itch.

If you are just doing simple queries then there isn't much apparent
difference.  If you want to be a "power user" of SQLite then APSW is for
you.  SQLite has many cool features such as virtual tables (you provide
the underlying data for the SQL queries to work on) and VFS (you provide
the file access).  See this link for more details:

  http://apsw.googlecode.com/svn/publish/pysqlite.html

Roger
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkpS6CUACgkQmOOfHg372QS0/gCgiHD9ukUlQYJGCIMWb9hNMLCM
Y/cAnid4dAeFHIdLBmKzGsXrvANkvhR5
=U0wg
-----END PGP SIGNATURE-----



From nagle at animats.com  Tue Jul  7 02:21:02 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 06 Jul 2009 23:21:02 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <0260603f$0$20657$c3e8da3@news.astraweb.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<7xvdm8thpo.fsf@ruckus.brouhaha.com>	<4a4fe6cb$0$1591$742ec2ed@news.sonic.net>	<7xfxdcqabg.fsf@ruckus.brouhaha.com>	<4a501a5e$0$1640$742ec2ed@news.sonic.net>	<0260559c$0$20657$c3e8da3@news.astraweb.com>	<7xws6nik0q.fsf@ruckus.brouhaha.com>
	<0260603f$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <4a52e8ef$0$1633$742ec2ed@news.sonic.net>

Steven D'Aprano wrote:
> On Sun, 05 Jul 2009 01:58:13 -0700, Paul Rubin wrote:
> 
>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>>> Okay, we get it. Parsing HTML 5 is a bitch. What's your point? I don't
>>> see how a case statement would help you here: you're not dispatching on
>>> a value, but running through a series of tests until one passes.
>> A case statement switch(x):... into a bunch of constant case labels
>> would be able to use x as an index into a jump vector, and/or do an
>> unrolled logarithmic (bisection-like) search through the tests, instead
>> of a linear search.
> 
> Yes, I'm aware of that, but that's not what John's code is doing -- he's 
> doing a series of if expr ... elif expr tests. I don't think a case 
> statement can do much to optimize that.

    (I didn't write that code; it's from "http://code.google.com/p/html5lib/",
which is a general purpose HTML 5 parser written in Python.  It's compatible
with ElementTree and/or BeautifulSoup.  I currently use a modified
BeautifulSoup for parsing real-world HTML in a small-scale crawler, and
I'm looking at this as an HTML 5 compatible replacement.)

					John Nagle


From nagle at animats.com  Tue Jul  7 02:31:26 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 06 Jul 2009 23:31:26 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <02605ef2$0$20657$c3e8da3@news.astraweb.com>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
Message-ID: <4a52eb5f$0$1663$742ec2ed@news.sonic.net>

Steven D'Aprano wrote:
> On Sun, 05 Jul 2009 10:12:54 +0200, Hendrik van Rooyen wrote:
> 
>> Python is not C.
> 
> John Nagle is an old hand at Python. He's perfectly aware of this, and 
> I'm sure he's not trying to program C in Python.
> 
> I'm not entirely sure *what* he is doing, and hopefully he'll speak up 
> and say, but whatever the problem is it's not going to be as simple as 
> that.

     I didn't write this code; I'm just using it.  As I said in the
original posting, it's from "http://code.google.com/p/html5lib".
It's from an effort to write a clean HTML 5 parser in Python for
general-purpose use.  HTML 5 parsing is well-defined for the awful
cases that make older browsers incompatible, but quite complicated.
The Python implementation here is intended partly as a reference
implementation, so browser writers have something to compare with.

     I have a small web crawler robust enough to parse
real-world HTML, which can be appallingly bad.  I currently use
an extra-robust version of BeautifulSoup, and even that sometimes
blows up.  So I'm very interested in a new Python parser which supposedly
handles bad HTML in the same way browsers do.  But if it's slower
than BeautifulSoup, there's a problem.

					John Nagle


From __peter__ at web.de  Tue Jul  7 02:33:48 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 07 Jul 2009 08:33:48 +0200
Subject: module name versus function name resolution conflict.
References: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
Message-ID: <h2uq7c$lq0$01$1@news.t-online.com>

rocky wrote:

> Someone recently reported a problem in pydb where a function defined
> in his program was conflicting with a module name that pydb uses. I
> think I understand what's wrong, but I don't have any elegant
> solutions to the problem. Suggestions would be appreciated.
> 
> In a nutshell, here's the problem:
> 
> In file fns:
> 
>   def foo(): print "foo"
> 
> In file pdebug.py:
> 
>   import fns, sys
> 
>   def trace_dispatch(frame, event, arg):
>       fns.foo()
>       print frame, event, arg
>       return trace_dispatch
> 
>   sys.settrace(trace_dispatch)
>   execfile('myprogram.py')
> 
> Finally file myprogram.py:
> 
>   def fns(): print "This is the *other* fns"
> 
> When you run pdebug.py you get:
> 
> $ python pdebug.py
> foo
> <frame object at 0xdd9030> call None
> foo
> <frame object at 0xdd9030> line None
> Traceback (most recent call last):
>   File "pdebug.py", line 7, in <module>
>     execfile('myprogram.py')
>   File "myprogram.py", line 1, in <module>
>     def fns(): print "This is the *other* fns"
>   File "pdebug.py", line 3, in trace_dispatch
>     fns.foo()
> AttributeError: 'function' object has no attribute 'foo'
> 
> 
> Basically inside the trace hook, local functions are visible and take
> precedence over (global) module names. I could move "import fns"
> inside trace_dispatch(), but I'd have to do that in all of the methods
> that module "fns" is used.  Also note that using the form:
>   from fns import foo
> 
> would eliminate the conflict on "fns", but I'd still have potential
> conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> reduce the chance of a conflict but not eliminate it.
> 
> Suggestions?

Can you run the program in another namespace?

execfile("myprogram.py", {"__name__":"__main__"})

Alternatively move trace_dispatch into yet another module and import it into 
pdebug.

from elsewhere import trace_dispatch

Peter




From wsysdu at gmail.com  Tue Jul  7 02:56:40 2009
From: wsysdu at gmail.com (Eric Wong)
Date: Tue, 07 Jul 2009 14:56:40 +0800
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com>
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com>
	<173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com>
Message-ID: <h2urjo$h4d$1@aioe.org>

Pedram wrote:

> Hello Mr. Dickinson. Glad to see you again :)
> 
> On Jul 6, 5:46 pm, Mark Dickinson <dicki... at gmail.com> wrote:
>> On Jul 6, 1:24 pm, Pedram <pm567... at gmail.com> wrote:
>>
>> > OK, fine, I read longobject.c at last! :)
>> > I found that longobject is a structure like this:
>>
>> > struct _longobject {
>> > struct _object *_ob_next;
>> > struct _object *_ob_prev;
>>
>> For current CPython, these two fields are only present in debug
>> builds;  for a normal build they won't exist.
> 
> I couldn't understand the difference between them. What are debug
> build and normal build themselves? And You mean in debug build
> PyLongObject is a doubly-linked-list but in normal build it is just 
an
> array (Or if not how it'll store in this mode)?
> 
we use the macro Py_TRACE_REFS to differ the code for debug build and 
normal build, that's to say, in debug build and normal build the codes 
are actually *different*. In debug build, not only PyLongObject but 
all Objects are linked by a doubly-linked-list and it can make the 
debug process less painful. But in normal build, objects are 
seperated! After an object is created, it will never be moved, so we 
can and should refer to an object only by it's address(pointer). 
There's no one-big-container like a list or an array for objects.



From astan.chee at al.com.au  Tue Jul  7 02:56:55 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 7 Jul 2009 16:56:55 +1000
Subject: copytree with timeout in windows
In-Reply-To: <4A52CAF2.7010707@timgolden.me.uk>
References: <4A52B9D0.9040608@al.com.au> <4A52CAF2.7010707@timgolden.me.uk>
Message-ID: <4A52F1B7.2070507@al.com.au>

Tim Golden wrote:
> Astan Chee wrote:
>   
>> Hi,
>> I'm trying to modify the copytree function in shutil so that any file 
>> being copied does not take more than 5 minutes (if it does, skip to the 
>> next one). 
>>     
>
> One suggestion is to use the CopyFileEx API
> exposed in the win32file module from pywin32. That
> allows for a callback function which can abort
> the copy (or issue a progress meter, etc.).
>   
Thanks, but looking in the documentation there is no callback function. 
Did you mean */the Progress Routine?
Thanks again
/*
> Obviously, you'd have to roll your own copytree, but
> that's not beyond the wit of man.
>
> TJG
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/adb98be6/attachment-0001.html>

From http  Tue Jul  7 03:38:50 2009
From: http (Paul Rubin)
Date: 07 Jul 2009 00:38:50 -0700
Subject: Looking for a slick way to classify relationship between two
	numbers, without tons of if/else
References: <mailman.2741.1246929917.8015.python-list@python.org>
Message-ID: <7x3a99gcxh.fsf@ruckus.brouhaha.com>

palewire <ben.welsh at gmail.com> writes:
> In my application, I'd like to have a function that compares two values,
> either of which may be null, and then classify the result depending on
> whether one is higher or lower than the other.

Didn't we just have a huge thread about that?  Using a special null
value is often (not always) a code smell.  But anyway (untested):

    def compare(a,b):
       if a is None and b is None:  # I'm guessing you meant this
           return "No data"
       if a == b:
           return "Stayed the same" if a != 0 else "Never had"
       elif a < b:
           return "gained"
       else:
           # we know here that a > b
           return "Lost some" if b > 0 else "Lost all"

I don't know what you intended to do in the case where exactly one of
(a,b) is None, so I'll leave that to you.


From mail at timgolden.me.uk  Tue Jul  7 03:42:55 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Tue, 07 Jul 2009 08:42:55 +0100
Subject: copytree with timeout in windows
In-Reply-To: <4A52F1B7.2070507@al.com.au>
References: <4A52B9D0.9040608@al.com.au> <4A52CAF2.7010707@timgolden.me.uk>
	<4A52F1B7.2070507@al.com.au>
Message-ID: <4A52FC7F.8050308@timgolden.me.uk>

Astan Chee wrote:
> Tim Golden wrote:
>> Astan Chee wrote:
>>  
>>> Hi,
>>> I'm trying to modify the copytree function in shutil so that any file 
>>> being copied does not take more than 5 minutes (if it does, skip to 
>>> the next one).     
>>
>> One suggestion is to use the CopyFileEx API
>> exposed in the win32file module from pywin32. That
>> allows for a callback function which can abort
>> the copy (or issue a progress meter, etc.).
>>   
> Thanks, but looking in the documentation there is no callback function. 
> Did you mean */the Progress Routine?


Well, depending on which hairs you're splitting, I would
argue that the Progress Routine *is* a callback function:
it is a function which is called back. But, yes, I
did mean that. :)

TJG


From piet at cs.uu.nl  Tue Jul  7 04:01:40 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 10:01:40 +0200
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<mailman.2724.1246918979.8015.python-list@python.org>
	<c64c03fd-3a5c-4e17-aa61-39016e12c435@t21g2000yqi.googlegroups.com>
Message-ID: <m2y6r0diqj.fsf@cs.uu.nl>

>>>>> Nile <nile_mcadams at yahoo.com> (N) wrote:

>N> I initialized the dictionary earlier in the program like this -

>N>   hashtable = {}

>N> I changed the "dict" to hashtable but I still get the same result
>N> I will try to learn about the defaultdict but I'm just trying to keep
>N> it as simple as I can for now

>N> Revised code

>N> for x in range(len(file_list)):
>N> 	d = open(file_list[x] , "r")
>N> 	data = d.readlines()
>N> 	k = 0
>N> 	k = above_or_below(data)
>N> 	print "here is the value that was returned ",k
>N> 	hashtable[k] = hashtable.get(k,0) + 1


>N> hashtable_list = hashtable.values()
>N> print "here is a list of the dictionary values ", hashtable_list
>N> print "the length of the dictionary is ", len(hashtable)

>N> Output
>N> # The first 3 lines are printed from the function
>N> # right before the return statement.  This output
>N> # snippet shows the last two stocks.  The function
>N> # SAYS it is returning the correct value but only
>N> # the last date seems to make it to the hashtable
>N> Function will return k which = 11/11/2008
>N> Function will return k which = 11/12/2008
>N> Function will return k which = 11/14/2008

>N> # this line is printed from the code above
>N> # I don't understand why all three dates don't
>N> # seem to make it to the main program.  Only
>N> # the last date seems to be recognized
>N> here is the value that was returned 11/14/2008

>N> Function will return k which = 11/11/2008
>N> Function will return k which = 11/12/2008
>N> Function will return k which = 11/14/2008
>N> here is the value that was returned 11/14/2008
>N> here is a list of the dictionary values [5]
>N> the length of the dictionary is 1
>>> Exit code: 0

Now in your code there is a 1-1 relation between printing 
"here is the value that was returned" and incrementing the hashtable
entry. In your log there are only 2 prints of "here is the value that
was returned" so how can the count be 5? Are you hiding something from
us? 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From chris at simplistix.co.uk  Tue Jul  7 04:06:49 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 09:06:49 +0100
Subject: Where does setuptools live?
In-Reply-To: <d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
Message-ID: <4A530219.6040007@simplistix.co.uk>

David Lyon wrote:
> setuptools... as far as I can see isn't actually installed until you
> install easyinstall...

That depends... I exclusively use buildout to manage my python packages, 
and sadly that relies on setuptools...

> Pip (http://pypi.python.org/pypi/pip) and enstall 
> (http://pypi.python.org/pypi/Enstaller/3.1.0) seem to be forks of 
> setuptools already...
> 
> So it looks like it's already been forked to some degree..
> 
> What hasn't happened is enough testing of pypi packages and installing
> with setuptools/pip/enstall from pypi.

What needs testing?

More important for me is which of these has the most active development 
community. How do we judge that?

> If the xmlrpc links actually "worked" on pypi...

What about it doesn't work?

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From duncan.booth at invalid.invalid  Tue Jul  7 04:19:47 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 7 Jul 2009 08:19:47 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<mailman.2753.1246941897.8015.python-list@python.org>
Message-ID: <Xns9C4173416946Fduncanbooth@127.0.0.1>

Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:

> for, if, and return were common keywords in FORTRAN.

Really? What does 'for' do in FORTRAN?

P.S. Does FORTRAN actually have keywords these days? Back when I learned it 
there was no such thing as a reserved word though for all I know they may 
have since added them.

-- 
Duncan Booth http://kupuguy.blogspot.com


From afriere at yahoo.co.uk  Tue Jul  7 04:48:30 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Tue, 7 Jul 2009 01:48:30 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com> 
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com> 
	<h2uhcb$blq$1@panix3.panix.com>
	<006eb26f$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <e246b4fe-00bd-485c-a1bd-92df4762ad92@j9g2000prh.googlegroups.com>

On Jul 7, 3:05?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:

[snip]

> Sense is, if you like, a "signed direction".

Or to put it another way, in the graphical representation of a vector,
'direction' is the line, 'sense' is the arrowhead.


From stefan_ml at behnel.de  Tue Jul  7 05:09:59 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 11:09:59 +0200
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a52eb5f$0$1663$742ec2ed@news.sonic.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
	<4a52eb5f$0$1663$742ec2ed@news.sonic.net>
Message-ID: <4a5310e7$0$31327$9b4e6d93@newsspool4.arcor-online.net>

John Nagle wrote:
>     I have a small web crawler robust enough to parse
> real-world HTML, which can be appallingly bad.  I currently use
> an extra-robust version of BeautifulSoup, and even that sometimes
> blows up.  So I'm very interested in a new Python parser which supposedly
> handles bad HTML in the same way browsers do.  But if it's slower
> than BeautifulSoup, there's a problem.

Well, if performance matters in any way, you can always use lxml's
blazingly fast parser first, possibly trying a couple of different
configurations, and only if all fail, fall back to running html5lib over
the same input. That should give you a tremendous speed-up over your
current code in most cases, while keeping things robust in the hard cases.

Note the numbers that Ian Bicking has for HTML parser performance:

http://blog.ianbicking.org/2008/03/30/python-html-parser-performance/

You should be able to run lxml's parser ten times in different
configurations (e.g. different charset overrides) before it even reaches
the time that BeautifulSoup would need to parse a document once. Given that
undeclared character set detection is something where BS is a lot better
than lxml, you can also mix the best of both worlds and use BS's character
set detection to configure lxml's parser if you notice that the first
parsing attempts fail.

And yes, html5lib performs pretty badly in comparison (or did, at the
time). But the numbers seem to indicate that if you can drop the ratio of
documents that require a run of html5lib below 30% and use lxml's parser
for the rest, you will still be faster than with BeautifulSoup alone.

Stefan


From dickinsm at gmail.com  Tue Jul  7 05:10:31 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 7 Jul 2009 02:10:31 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com> 
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com> 
	<173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com>
Message-ID: <2169e268-3fa7-4320-bef0-2619b8d1d040@h8g2000yqm.googlegroups.com>

On Jul 6, 4:13?pm, Pedram <pm567... at gmail.com> wrote:
> On Jul 6, 5:46?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> > On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
>
> > > OK, fine, I read longobject.c at last! :)
> > > I found that longobject is a structure like this:
>
> > > struct _longobject {
> > > ? ? struct _object *_ob_next;
> > > ? ? struct _object *_ob_prev;
>
> > For current CPython, these two fields are only present in debug
> > builds; ?for a normal build they won't exist.
>
> I couldn't understand the difference between them. What are debug
> build and normal build themselves? And You mean in debug build
> PyLongObject is a doubly-linked-list but in normal build it is just an
> array (Or if not how it'll store in this mode)?

No:  a PyLongObject is stored the same way (ob_size giving sign and
number of digits, ob_digit giving the digits themselves) whether or
not a debug build is in use.

A debug build does various things (extra checks, extra information) to
make it easier to track down problems.  On Unix-like systems, you can
get a debug build by configuring with the --with-pydebug flag.

The _ob_next and _ob_prev fields have nothing particularly to do with
Python longs; for a debug build, these two fields are added to *all*
Python objects, and provide a doubly-linked list that links all 'live'
Python objects together.  I'm not really sure what, if anything, the
extra information is used for within Python---it might be used by some
external tools, I guess.

Have you looked at the C-API documentation?

http://docs.python.org/c-api/index.html

_ob_next and _ob_prev are described here:

http://docs.python.org/c-api/typeobj.html#_ob_next

(These docs are for Python 2.6;  I'm not sure what version you're
working with.)

Mark


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 05:19:46 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 11:19:46 +0200
Subject: a little wsgi framework
In-Reply-To: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
References: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
Message-ID: <4a53132c$0$10839$426a34cc@news.free.fr>

timmyt a ?crit :
> i'm interested in getting opinions on a small wsgi framework i
> assembled from webob, sqlalchemy, genshi, and various code fragments i
> found on the inter-tubes
> 
> here is the interesting glue - any comments / suggestions would be
> much appreciated

<meta>
Well... My first comment would be about the usefulness of yet another 
Python web framework, but let's not worry about this...
</meta>

> ------------------
> the wsgi app
> ------------------
> def application(environ, start_response):
>     path = environ.get('PATH_INFO', '').lstrip('/')
> 
>     for regex, callback in urls:
>         match = re.search(regex, path)


I don't know where these "urls" come from. But anyway : if they live in 
some sort of long-running process, you may want to precompile them.

>         if match:
>             environ['myapp.url_args'] = match.groups()
>             request = webob.Request(environ)
> 
>             try:
>                 return callback(request, start_response)
>             except Exception, ex:

How are redirect etc handled ?

>                 start_response('500 Internal Server Error', [('Content-
> Type', 'text/plain')])
>                 return [traceback.format_exc()]

A configuration option controlling the display of the traceback would be 
fine - I surely don't want the traceback being displayed to anyone when 
  the app goes into production.

Also, logging the error and traceback might be useful.


>     start_response('404 Not Found', [('Content-Type', 'text/plain')])
>     return ["Couldn't find the URL specified."]
> 

And in both cases, having the ability to use "custom" 500 and 404 pages 
might be nice too.


> ----------------------------------
> the controller decorator
> ----------------------------------
> def web_decorator(filename, method='html'):
 >
>     def decorator(target):

May I suggest some renaming here ?

filename => path (or 'template_path' ?)
method   => content_type
target   => controller or function or callback or....

>         def wrapper(request, start_response):
> 
>             #genshi TemplateLoader
>             template = loader.load(filename)
> 
>             global config

Probably not thread-safe....

>             try:
>                 return_dict = target(request, start_response)
>                 return_string = template.generate(**return_dict).render
> (method)


Renaming again:
return_dict => context
return_string => data or text or ???

>                 config['database.Session'].commit()
>             except:
>                 config['database.Session'].rollback()
>                 raise
>             finally:
>                 config['database.Session'].remove()

This doesn't leave much control on transactions... Sometimes you want to 
handle it manually one way or another.

>             #TODO: alter 'Content-Type' per method being passed
>             start_response('200 OK', [('Content-Type', 'text/html')])
>             return [return_string]

Ok, so here again, I don't understand how redirects can work. Also, if 
you do use start_response here, I don't get why you still pass it to the 
callback function.

>         return wrapper
> 
>     return decorator

slightly OT, but preserving infos on the decorated function might help 
too (introspection, debugging etc).


My 2 cents...


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 05:27:52 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 11:27:52 +0200
Subject: A Bug By Any Other Name ...
In-Reply-To: <mailman.2746.1246935242.8015.python-list@python.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
Message-ID: <4a531512$0$9355$426a74cc@news.free.fr>

Daniel Fetchinson a ?crit :
(snip)
> and my point is that users
> are most of time correct when they assume that something will work the
> same way as in C.

Oh, really ? They would surely be wrong if they'd expect the for loop to 
have any similarity with a C for loop, or - a *very* common error - if 
they'd expect assignment to work the same way as in C.

> So I'd think that putting a warning in a FAQ or a Python Gotchas list
> about ++n would be very useful for many users.

Might eventually be useful, but I can't hardly recall of more than a 
couple threads on this topic in 8+ years.



From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 05:29:10 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 11:29:10 +0200
Subject: A Bug By Any Other Name ...
In-Reply-To: <mailman.2754.1246945937.8015.python-list@python.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>	<h2ujrs$4c0$1@ger.gmane.org>
	<mailman.2754.1246945937.8015.python-list@python.org>
Message-ID: <4a531560$0$9355$426a74cc@news.free.fr>

Daniel Fetchinson a ?crit :
>>> Yes, there are plenty of languages other than Java and C, but the
>>> influence of C is admittedly huge in Python. Why do you think loops
>>> are called "for", conditionals "if" or "while", functions return via
>>> "return", loops terminate via "break" and keep going via "continue"
>>> and why is comparison written as "==", etc, etc? All of these are
>>> coming from C (or an even earlier language) and my point is that users
>> 	for, if, and return were common keywords in FORTRAN.
>>
>> 	Not to mention BASIC
>>
>> 	Both of which predate C
> 
> Yes, hence my comment above, ".... coming from C (or an even earlier
> language) ......".


Mmm... Should we then claim that "the influence of FORTRAN is admittedly 
huge in Python" ?-)



From rocky at gnu.org  Tue Jul  7 05:44:07 2009
From: rocky at gnu.org (rocky)
Date: Tue, 7 Jul 2009 02:44:07 -0700 (PDT)
Subject: module name versus function name resolution conflict.
References: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
	<h2uq7c$lq0$01$1@news.t-online.com>
Message-ID: <f22b8224-97fa-4296-b175-19bf19b21fd8@d32g2000yqh.googlegroups.com>

On Jul 7, 2:33?am, Peter Otten <__pete... at web.de> wrote:
> rocky wrote:
> > Someone recently reported a problem in pydb where a function defined
> > in his program was conflicting with amodulenamethat pydb uses. I
> > think I understand what's wrong, but I don't have any elegant
> > solutions to the problem. Suggestions would be appreciated.
>
> > In a nutshell, here's the problem:
>
> > In file fns:
>
> > ? def foo(): print "foo"
>
> > In file pdebug.py:
>
> > ? import fns, sys
>
> > ? def trace_dispatch(frame, event, arg):
> > ? ? ? fns.foo()
> > ? ? ? print frame, event, arg
> > ? ? ? return trace_dispatch
>
> > ? sys.settrace(trace_dispatch)
> > ? execfile('myprogram.py')
>
> > Finally file myprogram.py:
>
> > ? def fns(): print "This is the *other* fns"
>
> > When you run pdebug.py you get:
>
> > $ python pdebug.py
> > foo
> > <frame object at 0xdd9030> call None
> > foo
> > <frame object at 0xdd9030> line None
> > Traceback (most recent call last):
> > ? File "pdebug.py", line 7, in <module>
> > ? ? execfile('myprogram.py')
> > ? File "myprogram.py", line 1, in <module>
> > ? ? def fns(): print "This is the *other* fns"
> > ? File "pdebug.py", line 3, in trace_dispatch
> > ? ? fns.foo()
> > AttributeError: 'function' object has no attribute 'foo'
>
> > Basically inside the trace hook, local functions are visible and take
> > precedence over (global)modulenames.

I was sloppy here. The "local" is the wrong word as suggested by the
first remedy proposed.
"entry in the global namespace dictionary" is probably closer to the
truth.

> > I could move "import fns"
> > inside trace_dispatch(), but I'd have to do that in all of the methods
> > thatmodule"fns" is used. ?Also note that using the form:
> > ? from fns import foo
>
> > would eliminate the conflict on "fns", but I'd still have potential
> > conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> > reduce the chance of a conflict but not eliminate it.
>
> > Suggestions?
>
> Can you run the program in another namespace?
>
> execfile("myprogram.py", {"__name__":"__main__"})
>
> Alternatively move trace_dispatch into yet anothermoduleand import it into
> pdebug.
>
> from elsewhere import trace_dispatch
>
> Peter

Both of these work. Thanks! (I haven't figured out how to adapt it to
the messier context of the program yet). The second suggestion
interesting/weird:
by putting trace_dispatch in another module, compilation and name/
function resolution of fns.foo
is done before myprogram has a chance to redefine fns.



From lie.1296 at gmail.com  Tue Jul  7 06:08:14 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 10:08:14 GMT
Subject: Method to separate unit-test methods and data?
In-Reply-To: <mailman.2645.1246819693.8015.python-list@python.org>
References: <be8f57070907051146m5c944fd8vfb98282dbdcc3145@mail.gmail.com>
	<mailman.2645.1246819693.8015.python-list@python.org>
Message-ID: <i8F4m.3224$ze1.1839@news-server.bigpond.net.au>

Nick Daly wrote:
> Hi,
> 
> I was wondering if it's possible / if there are any simple methods
> known of storing unit-test functions and their data in separate files?
> 
> Perhaps this is a strange request, but it does an excellent job of
> modularizing code.  As far as revision control goes, it makes it
> easier to discern between new or changed test cases, and changes in
> the test data.
> 
<snip>
> Does anyone have any solutions for these problems?  First, is there a
> known and simple way to separate unit-test data and methods into
> separate files?  Secondly, if not, is there a simple way to convert
> strings into other base types, like lists, dictionaries, and so forth?
> Or, am I going to have to write my own list-parsing methods?  Would
> pickling help?  I haven't yet had a chance to look into if or how that
> would work...  If there's anything else I can clarify about this
> request, feel free to let me know.
> 

It is usually not a very good idea to complicate the testing framework
with configuration files (as then you will have two things to be
tested). Unless the testing data is very huge (so huge that it
interferes with reading and writing the testing code), and huge data is
necessary for the test, it is much simpler and better to just put the
data into the test code. In cases where you want to have fairly complex
object (list, etc) you can "import" the test data. Pickling is usually
unnecessary unless you want to store instance data (classes, etc).

-- code.py --
def add(a, b):
    return a + b

-- test.py --
import unittest

# import the file we're testing
import code

# imports the data from separate file
from testdata import data

class AddCase(unittest.TestCase):
    def test_add():
        for case in data:
            self.assertEqual(code.add(case[0], case[1]), case[2])

-- testdata.py --
data = [(0, 0, 0),
        (1, 0, 1),
        (0, 1, 1),
        (1, -1, 0),
       ]


From pm567426 at gmail.com  Tue Jul  7 07:06:07 2009
From: pm567426 at gmail.com (Pedram)
Date: Tue, 7 Jul 2009 04:06:07 -0700 (PDT)
Subject: How Python Implements "long integer"?
References: <53f6b9bf-9661-4baf-b5c7-57a6bfee370d@t13g2000yqt.googlegroups.com>
	<b6cf01d1-382c-40bc-85c3-9665214179dc@t21g2000yqi.googlegroups.com> 
	<088097b7-7a6b-4272-991e-60e6b410c68c@37g2000yqp.googlegroups.com> 
	<173653b0-3468-42c0-bb51-d53e7a520917@y17g2000yqn.googlegroups.com> 
	<2169e268-3fa7-4320-bef0-2619b8d1d040@h8g2000yqm.googlegroups.com>
Message-ID: <06ec69cc-2183-41b6-92ac-eafaa3b5cd02@n11g2000yqb.googlegroups.com>

On Jul 7, 1:10?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 6, 4:13?pm, Pedram <pm567... at gmail.com> wrote:
>
>
>
> > On Jul 6, 5:46?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> > > On Jul 6, 1:24?pm, Pedram <pm567... at gmail.com> wrote:
>
> > > > OK, fine, I read longobject.c at last! :)
> > > > I found that longobject is a structure like this:
>
> > > > struct _longobject {
> > > > ? ? struct _object *_ob_next;
> > > > ? ? struct _object *_ob_prev;
>
> > > For current CPython, these two fields are only present in debug
> > > builds; ?for a normal build they won't exist.
>
> > I couldn't understand the difference between them. What are debug
> > build and normal build themselves? And You mean in debug build
> > PyLongObject is a doubly-linked-list but in normal build it is just an
> > array (Or if not how it'll store in this mode)?
>
> No: ?a PyLongObject is stored the same way (ob_size giving sign and
> number of digits, ob_digit giving the digits themselves) whether or
> not a debug build is in use.
>
> A debug build does various things (extra checks, extra information) to
> make it easier to track down problems. ?On Unix-like systems, you can
> get a debug build by configuring with the --with-pydebug flag.
>
> The _ob_next and _ob_prev fields have nothing particularly to do with
> Python longs; for a debug build, these two fields are added to *all*
> Python objects, and provide a doubly-linked list that links all 'live'
> Python objects together. ?I'm not really sure what, if anything, the
> extra information is used for within Python---it might be used by some
> external tools, I guess.
>
> Have you looked at the C-API documentation?
>
> http://docs.python.org/c-api/index.html
>
> _ob_next and _ob_prev are described here:
>
> http://docs.python.org/c-api/typeobj.html#_ob_next
>
> (These docs are for Python 2.6; ?I'm not sure what version you're
> working with.)
>
> Mark

It seems there's an island named Python!
Thanks for links, I'm on reading them.


From serverin2000 at yahoo.com  Tue Jul  7 07:07:46 2009
From: serverin2000 at yahoo.com (RAM)
Date: Tue, 7 Jul 2009 04:07:46 -0700 (PDT)
Subject: generation of keyboard events
References: <cdc62209-b1b1-4e7d-9450-5d8d05688ed5@p29g2000yqh.googlegroups.com>
	<Vh44m.1902$cl4.90@flpi150.ffdc.sbc.com>
	<d41aaa27-5c02-411f-a279-85fee5726d4d@l5g2000pra.googlegroups.com>
	<mailman.2678.1246870949.8015.python-list@python.org>
Message-ID: <df23f0da-6b9c-4dd8-8b6b-b29a12bcc5cb@a39g2000pre.googlegroups.com>

On 6 July, 10:02, Simon Brunning <si... at brunningonline.net> wrote:
> 2009/7/6 RAM <serverin2... at yahoo.com>:
>
> > I am trying to do this on windows. My program(executable) has been
> > written in VC++ and when I run this program, I need to click on one
> > button on the program GUI i,e just I am entering "Enter key" on the
> > key board. But this needs manual process. So i need to write a python
> > script which invokes my program and pass "Enter key" event to my
> > program so that it runs without manual intervention.
>
> Try <http://pywinauto.openqa.org/>.
>
> --
> Cheers,
> Simon B.

Thank you all for the help the below url helped me in accomplishing my
task

http://www.rutherfurd.net/python/sendkeys/index.html

regards
Sreerama V


From no.email at please.post  Tue Jul  7 07:50:01 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 11:50:01 +0000 (UTC)
Subject: ISO library ref in printed form
Message-ID: <h2vcp9$66b$1@reader1.panix.com>



Does anyone know where I can buy the Python library reference in
printed form?  (I'd rather not print the whole 1200+-page tome
myself.)  I'm interested in both/either 2.6 and 3.0.

TIA!

kj


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 07:51:11 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 13:51:11 +0200
Subject: Why re.match()?
In-Reply-To: <h2tngh$12s$1@reader1.panix.com>
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
Message-ID: <4a5336a8$0$11315$426a74cc@news.free.fr>

kj a ?crit :
> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
> 
>> kj a ?crit :
>> (snipo
>>> To have a special-case
>>> re.match() method in addition to a general re.search() method is
>>> antithetical to language minimalism,
> 
>> FWIW, Python has no pretention to minimalism.
> 
> Assuming that you mean by this that Python's authors have no such
> pretensions:
> 
> "There is real value in having a small language."
> 
> 			Guido van Rossum, 2007.07.03
> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html

There are some differences between "small" and "minimal"...

> So there.
> 
> BTW, that's just one example.  I've seen similar sentiments expressed
> by Guido over and over and over: any new proposed enhancement to
> Python must be good enough in his mind to justify cluttering the
> language.  That attitude counts as minimalism in my book.

And in mine, it counts as "keeping the language's evolution under 
control" - which is still not the same thing as being "minimalist". If 
Python really was on the "minimalist" side, you wouldn't even have 
"class" or "def" statements - both being mostly syntactic sugar. And 
let's not even talk about @decorator syntax...



From dnhkng at googlemail.com  Tue Jul  7 08:00:09 2009
From: dnhkng at googlemail.com (Dr Mephesto)
Date: Tue, 7 Jul 2009 05:00:09 -0700 (PDT)
Subject: Python/pyobjC Apps on iPhone now a possibility?
Message-ID: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>

I have been following the discussion about python and pyobjc on the
iphone, and it seemed to me that the app-store rules prohibited
embedded interpreters; so, python apps are a no-no.

But now it seems that the Rubyists have the option that we don't. It
seems there is a company, http://rhomobile.com/home, that has an SDK
that allows ruby programs to be embedded together with an interpreter
in an app! More interesting is the fact that several of these hybrid
apps seem to have been accepted on the itunes app store.

Here's a quote from a representative, found on this blog:
http://www.rubyinside.com/rhodes-develop-full-iphone-rim-and-symbian-apps-using-ruby-1475.html

"...First of all, to clarify, we precompile all framework and app code
down to Ruby 1.9 VM bytecode. This yields great performance
advantages. We also disable eval and other dynamic execution aspects
of Ruby. In the end, on all platforms your app gets compiled with our
framework all into one single executable, indistinguishable from any
other executable.

But even if we were shipping a fullon Ruby interpreter without
compiling to bytecode and leaving dynamic evaluation enabled (as has
been well remarked in the blogosphere by now) App Store rule 3.3.2
does not disallow interpreters but only downloading code to be
executed by the interpreter."

So, the question is, can the same thing be done for Python apps?


From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 08:00:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 07 Jul 2009 12:00:33 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com>
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org>
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org>
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
	<006eb461$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2755.1246947020.8015.python-list@python.org>
Message-ID: <006f13c9$0$9711$c3e8da3@news.astraweb.com>

On Mon, 06 Jul 2009 22:18:20 -0700, Chris Rebert wrote:

>> Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.
[...]
> Well, yes, but when would you apply it twice in a row?

My point was that unary + isn't a no-op, and therefore neither is ++. For 
Decimal, I can't think why you'd want to apply ++x, but for other 
objects, who knows?

Here's a toy example:

>>> class Spam(str):
...     def __pos__(self):
...         return self.__class__("spam " + self)
...
>>> s = Spam("")
>>> ++++s
'spam spam spam spam '



-- 
Steven


From david.lyon at preisshare.net  Tue Jul  7 08:02:07 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 07 Jul 2009 08:02:07 -0400
Subject: Where does setuptools =?UTF-8?Q?live=3F?=
In-Reply-To: <4A530219.6040007@simplistix.co.uk>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
Message-ID: <eff5e178f7200eec6637807f209b8d2d@preisshare.net>

On Tue, 07 Jul 2009 09:06:49 +0100, Chris Withers <chris at simplistix.co.uk>
wrote:
>> What hasn't happened is enough testing of pypi packages and installing
>> with setuptools/pip/enstall from pypi.
> 
> What needs testing?

It's software... therefore it needs testing...

David




From paul.nospam at rudin.co.uk  Tue Jul  7 08:03:54 2009
From: paul.nospam at rudin.co.uk (Paul Rudin)
Date: Tue, 07 Jul 2009 13:03:54 +0100
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>
	<h2hap5$qv8$2@reader1.panix.com>
	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>
	<h2i54b$eg3$1@reader1.panix.com>
	<4a4e2227$0$7801$426a74cc@news.free.fr>
	<h2tngh$12s$1@reader1.panix.com>
	<4a5336a8$0$11315$426a74cc@news.free.fr>
Message-ID: <87prccsnrp.fsf@rudin.co.uk>

Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:

> kj a ?crit :
>> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
>>
>>> kj a ?crit :
>>> (snipo
>>>> To have a special-case
>>>> re.match() method in addition to a general re.search() method is
>>>> antithetical to language minimalism,
>>
>>> FWIW, Python has no pretention to minimalism.
>>
>> Assuming that you mean by this that Python's authors have no such
>> pretensions:
>>
>> "There is real value in having a small language."
>>
>> 			Guido van Rossum, 2007.07.03
>> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
>
> There are some differences between "small" and "minimal"...
>

There's also a difference between the language and its standard
library.


From chris at simplistix.co.uk  Tue Jul  7 08:07:48 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 13:07:48 +0100
Subject: Where does setuptools live?
In-Reply-To: <eff5e178f7200eec6637807f209b8d2d@preisshare.net>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
	<eff5e178f7200eec6637807f209b8d2d@preisshare.net>
Message-ID: <4A533A94.7030503@simplistix.co.uk>

David Lyon wrote:
> On Tue, 07 Jul 2009 09:06:49 +0100, Chris Withers <chris at simplistix.co.uk>
> wrote:
>>> What hasn't happened is enough testing of pypi packages and installing
>>> with setuptools/pip/enstall from pypi.
>> What needs testing?
> 
> It's software... therefore it needs testing...

Yes, which is why I asked WHAT needs testing? :-)

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From david.lyon at preisshare.net  Tue Jul  7 08:21:50 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 07 Jul 2009 08:21:50 -0400
Subject: Where does setuptools =?UTF-8?Q?live=3F?=
In-Reply-To: <4A533A94.7030503@simplistix.co.uk>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
	<eff5e178f7200eec6637807f209b8d2d@preisshare.net>
	<4A533A94.7030503@simplistix.co.uk>
Message-ID: <fc81c0a388e0f1788508dfdaaa58344e@preisshare.net>

On Tue, 07 Jul 2009 13:07:48 +0100, Chris Withers <chris at simplistix.co.uk>
wrote:
>>>> What hasn't happened is enough testing of pypi packages and installing
>>>> with setuptools/pip/enstall from pypi.
>>> What needs testing?
>> 
>> It's software... therefore it needs testing...
> 
> Yes, which is why I asked WHAT needs testing? :-)

I've written a package manager gui. I think it is
orderly to comprehensively ascertain which packages will 
and won't install from pypi with the tool.

I'll run the same install test for pip, easyinstall 
and enstall. And come up with a preferred installer.

Which I will then suggest as the preferred tool.

David




From chris at simplistix.co.uk  Tue Jul  7 08:28:14 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Tue, 07 Jul 2009 13:28:14 +0100
Subject: Where does setuptools live?
In-Reply-To: <fc81c0a388e0f1788508dfdaaa58344e@preisshare.net>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<4A530219.6040007@simplistix.co.uk>
	<eff5e178f7200eec6637807f209b8d2d@preisshare.net>
	<4A533A94.7030503@simplistix.co.uk>
	<fc81c0a388e0f1788508dfdaaa58344e@preisshare.net>
Message-ID: <4A533F5E.1080004@simplistix.co.uk>

David Lyon wrote:
> I've written a package manager gui. I think it is
> orderly to comprehensively ascertain which packages will 
> and won't install from pypi with the tool.
> 
> I'll run the same install test for pip, easyinstall 
> and enstall. And come up with a preferred installer.
> 
> Which I will then suggest as the preferred tool.

Cool :-)

If you can publish your results or make the raw data downloadable 
somewhere (especially which packages fail with which installers) I'm 
sure a lot of people would find that *very* interesting...

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From zdenekmaxa at yahoo.co.uk  Tue Jul  7 08:38:16 2009
From: zdenekmaxa at yahoo.co.uk (Zdenek Maxa)
Date: Tue, 07 Jul 2009 14:38:16 +0200
Subject: Tkinter.Canvas thread safety problem?
Message-ID: <4A5341B8.5000502@yahoo.co.uk>

Hello,

I have started a project using Tkinter. The application performs some
regular checks in a thread and updates Canvas components. I have
observed that sometimes the application hangs when it is about to call
canvas.itemconfig() when the thread is about to terminate in the next loop.

Experimenting with this problem for a while, I have compiled a little
example which always reproduces the problem. Commenting out the line 52
(before canvas.itemconfig()), the example always finishes all right,
having the delay there, it hangs.

I would like to ask if you could have a look at the snippet in the
attachment and tell me if that is actually me doing something wrong or
indeed Tkinter thread safety problem and what the workaround could be.

Could you please also comment on wxPython thread safety?

I am using:

Python 2.5.4 (r254:67916, Feb 17 2009, 20:16:45)
[GCC 4.3.3]

2.6.26-1-amd64 #1 SMP Fri Mar 13 19:34:38 UTC 2009 x86_64 GNU/Linux

Thanks in advance,
Zdenek
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tkinter_thread_safety.py
Type: text/x-python
Size: 2278 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/de3e4d7b/attachment-0001.py>

From lie.1296 at gmail.com  Tue Jul  7 08:48:34 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Tue, 07 Jul 2009 12:48:34 GMT
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006ebea2$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<h2nqpf$d91$1@reader1.panix.com>	<mailman.2688.1246883548.8015.python-list@python.org>	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <CuH4m.3259$ze1.429@news-server.bigpond.net.au>

Steven D'Aprano wrote:
> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
> 
>> When people are fighting over things like `sense`, although sense may
>> not be strictly wrong dictionary-wise, it smells of something burning...
> 
> That would be my patience.
> 
> I can't believe the direction this discussion has taken.

Me neither.

> Anybody sensible 
> would be saying "Oh wow, I've just learned a new meaning to the word, 
> that's great, I'm now less ignorant than I was a minute ago". But oh no, 
> we mustn't use a standard meaning to a word, heaven forbid we disturb 
> people's ignorance by teaching them something new.

A meaning of a word is meaningless if nobody apart the writer
understands it. The purpose of code is 1) to communicate with the
computer, 2) to communicate with fellow programmer. The second point is
especially important if the code are written for pedantic purpose.
Teaching is largely one-way communication and often students that does
not understand about a slight point could not or would not communicate
their feelings because they think it is too silly. If the use of word is
criticized on a two-way communication channel (e.g. newsgroup), it
should raise a question of whether the word should be described first or
whether a synonym would be more suitable for the purpose. Most of these
do not apply on practical, non-pedantic purpose though, since in
non-pedantic settings you are expected to know and use the jargons
however (in)sensible they may be at first sight.

> It's as simple as this: using `sense` as a variable name to record the 
> sense of a function is not a code smell, any more than using `flag` to 
> record a flag would be, or `sign` to record the sign of an object.

Nobody said code smell... linguistic smell is more appropriate.

> If you 
> don't know the appropriate meanings of the words sense, flag or sign, 
> learn them, don't dumb down my language.


From jeanmichel at sequans.com  Tue Jul  7 08:51:10 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 07 Jul 2009 14:51:10 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006ebea2$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<h2nqpf$d91$1@reader1.panix.com>	<mailman.2688.1246883548.8015.python-list@python.org>	<006e795f$0$9711$c3e8da3@news.astraweb.com>	<h2uhcb$blq$1@panix3.panix.com>	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <4A5344BE.2080006@sequans.com>

Steven D'Aprano wrote:
> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
>
>   
>> When people are fighting over things like `sense`, although sense may
>> not be strictly wrong dictionary-wise, it smells of something burning...
>>     
>
> That would be my patience.
>
> I can't believe the direction this discussion has taken. Anybody sensible 
> would be saying "Oh wow, I've just learned a new meaning to the word, 
> that's great, I'm now less ignorant than I was a minute ago". But oh no, 
> we mustn't use a standard meaning to a word, heaven forbid we disturb 
> people's ignorance by teaching them something new.
>
> It's as simple as this: using `sense` as a variable name to record the 
> sense of a function is not a code smell, any more than using `flag` to 
> record a flag would be, or `sign` to record the sign of an object. If you 
> don't know the appropriate meanings of the words sense, flag or sign, 
> learn them, don't dumb down my language.
>
>   

Can't we just calm down ? I'm really sorry my ignorance started this 
thread, and my apologies go to Kj who's obviously more fluent in english 
than me.
I've never used sense in that way before, nor I've seen used by others 
until now. However Kj is right, and my dictionary seems wrong 
(wordreference.com). I've searched through others dictionaries and find 
out this is actually applicable to functions. My bad.

JM


From davea at ieee.org  Tue Jul  7 08:55:13 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 08:55:13 -0400
Subject: Python Error from Apress book
In-Reply-To: <op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A5345B1.8050306@ieee.org>

Gabriel Genellina wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">En Mon, 
> 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com> escribi?:
>
>> When I try to run the command as outlined in
>> the book "simple_markup2.py < test_input.txt > test_output.html i get 
>> the
>> following error every time.
>>
>> IOError: [Errno 9] Bad file descriptor
>
> That's a Windows problem. When you execute the script as itself 
> (either as you do in the command line, or by double-clicking on it), 
> it doesn't have valid standard handles.
> You have to invoke Python explicitely:
>
> python simple_markup2.py < test_input.txt > test_output.html
>
> (you may need to specify the full path to python.exe, or add the 
> directory where Python is installed to your system PATH).
>
I use stdout this way all the time, with no problem (python 2.6, Windows 
XP).  But as you point out, stdin redirection doesn't seem to work using 
the file associations.  I do get a different error though. When I look 
at sys.stdin, it shows an open file, with handle of zero, as expected.  
But when I do a raw_input(), it gets:
     EOFError: EOF when reading a line




From stefan_ml at behnel.de  Tue Jul  7 09:01:07 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 15:01:07 +0200
Subject: parsing times like "5 minutes ago"?
In-Reply-To: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
References: <gyw4m.3568$bq1.553@nlpi066.nbdc.sbc.com>
Message-ID: <4a534713$0$31332$9b4e6d93@newsspool4.arcor-online.net>

mh at pixar.com wrote:
> I'm looking for something like Tcl's [clock scan] command which parses
> human-readable time strings such as:
> 
>     % clock scan "5 minutes ago"
>     1246925569
>     % clock scan "tomorrow 12:00"
>     1246993200
>     % clock scan "today + 1 fortnight"
>     1248135628
> 
> Does any such package exist for Python?

Is this only for English times or is I18N a concern?

Stefan


From python at mrabarnett.plus.com  Tue Jul  7 09:07:00 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 14:07:00 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2ujrs$4c0$1@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
Message-ID: <4A534874.8050503@mrabarnett.plus.com>

Dennis Lee Bieber wrote:
> On Mon, 6 Jul 2009 19:48:39 -0700, Daniel Fetchinson
> <fetchinson at googlemail.com> declaimed the following in
> gmane.comp.python.general:
> 
>> Yes, there are plenty of languages other than Java and C, but the
>> influence of C is admittedly huge in Python. Why do you think loops
>> are called "for", conditionals "if" or "while", functions return via
>> "return", loops terminate via "break" and keep going via "continue"
>> and why is comparison written as "==", etc, etc? All of these are
>> coming from C (or an even earlier language) and my point is that users
> 
> 	for, if, and return were common keywords in FORTRAN.
> 
> 	Not to mention BASIC
> 
> 	Both of which predate C
> 
FORTRAN also used "=" for assignment (and ".EQ." for comparison).

C was derived from BCPL which used ":=" for assignment and "=" for
comparison.


From james at agentultra.com  Tue Jul  7 09:07:58 2009
From: james at agentultra.com (J Kenneth King)
Date: Tue, 07 Jul 2009 09:07:58 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
Message-ID: <85ljn0ej4h.fsf@agentultra.com>

Dr Mephesto <dnhkng at googlemail.com> writes:

> I have been following the discussion about python and pyobjc on the
> iphone, and it seemed to me that the app-store rules prohibited
> embedded interpreters; so, python apps are a no-no.
>
> But now it seems that the Rubyists have the option that we don't. It
> seems there is a company, http://rhomobile.com/home, that has an SDK
> that allows ruby programs to be embedded together with an interpreter
> in an app! More interesting is the fact that several of these hybrid
> apps seem to have been accepted on the itunes app store.
>
> Here's a quote from a representative, found on this blog:
> http://www.rubyinside.com/rhodes-develop-full-iphone-rim-and-symbian-apps-using-ruby-1475.html
>
> "...First of all, to clarify, we precompile all framework and app code
> down to Ruby 1.9 VM bytecode. This yields great performance
> advantages. We also disable eval and other dynamic execution aspects
> of Ruby. In the end, on all platforms your app gets compiled with our
> framework all into one single executable, indistinguishable from any
> other executable.
>
> But even if we were shipping a fullon Ruby interpreter without
> compiling to bytecode and leaving dynamic evaluation enabled (as has
> been well remarked in the blogosphere by now) App Store rule 3.3.2
> does not disallow interpreters but only downloading code to be
> executed by the interpreter."
>
> So, the question is, can the same thing be done for Python apps?

I love Python and all, but it'd be apt to ask, what's the point?

The iPhone is running on what? A 400Mhz ARM processor? Resources on the
device are already limited; running your program on top of an embedded
Python interpreter would only be adding pressure to the constraints;
even if it was an optimized interpreter.

Might as well just suck it up and learn C/Objective-C .. it's really not
that hard. It took me about a day to pick up the language and another
two or three to finagle with the libraries.


From davea at ieee.org  Tue Jul  7 09:10:14 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 09:10:14 -0400
Subject: module name versus function name resolution conflict.
In-Reply-To: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
References: <30998c64-2c9c-4dd6-a495-90423267dd64@32g2000yqj.googlegroups.com>
Message-ID: <4A534936.7060300@ieee.org>

rocky wrote:
> Someone recently reported a problem in pydb where a function defined
> in his program was conflicting with a module name that pydb uses. I
> think I understand what's wrong, but I don't have any elegant
> solutions to the problem. Suggestions would be appreciated.
>
> In a nutshell, here's the problem:
>
> In file fns:
>
>   def foo(): print "foo"
>
> In file pdebug.py:
>
>   import fns, sys
>
>   def trace_dispatch(frame, event, arg):
>       fns.foo()
>       print frame, event, arg
>       return trace_dispatch
>
>   sys.settrace(trace_dispatch)
>   execfile('myprogram.py')
>
> Finally file myprogram.py:
>
>   def fns(): print "This is the *other* fns"
>
> When you run pdebug.py you get:
>
> $ python pdebug.py
> foo
> <frame object at 0xdd9030> call None
> foo
> <frame object at 0xdd9030> line None
> Traceback (most recent call last):
>   File "pdebug.py", line 7, in <module>
>     execfile('myprogram.py')
>   File "myprogram.py", line 1, in <module>
>     def fns(): print "This is the *other* fns"
>   File "pdebug.py", line 3, in trace_dispatch
>     fns.foo()
> AttributeError: 'function' object has no attribute 'foo'
>
>
> Basically inside the trace hook, local functions are visible and take
> precedence over (global) module names. I could move "import fns"
> inside trace_dispatch(), but I'd have to do that in all of the methods
> that module "fns" is used.  Also note that using the form:
>   from fns import foo
>
> would eliminate the conflict on "fns", but I'd still have potential
> conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> reduce the chance of a conflict but not eliminate it.
>
> Suggestions?
>
>
>   
Some context would be useful.  For example, you may be writing pdebug.py 
as a library to be used by other developers, and you want to minimize 
the likelihood that arbitrary code they write will conflict.  If you own 
all the code, I'd just say to rename one or the other.

My preference is also for using import of myprogram, as I've never 
needed execfile().  But if you need one of the features of execfile(), 
and really want myprogram in the same namespace, then you probably ought 
to obfuscate the other import.

Instead of   import fns,    try:
       import fns as _module_fns
And of course any references to the module will use the longer name.

The leading underscore is a clue that the name is not to be used outside 
of the module.  And the prefix 'module' helps to make it unlikely 
they'll make a data or function or class with that name.




From philip at semanchuk.com  Tue Jul  7 09:18:32 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Tue, 7 Jul 2009 09:18:32 -0400
Subject: How to map size_t using ctypes?
In-Reply-To: <op.uwn9hrmpx6zn5v@lepton.softlabbsas.com.ar>
References: <mailman.2691.1246888326.8015.python-list@python.org>
	<7belo1F21fs3vU1@mid.uni-berlin.de>
	<DB4ED723-C8DD-492F-A7CC-B3CE14F8B723@semanchuk.com>
	<op.uwn9hrmpx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <9DD9E3DD-1C6E-4B12-A9DD-9F768832DF60@semanchuk.com>


On Jul 6, 2009, at 11:51 PM, Gabriel Genellina wrote:

> En Mon, 06 Jul 2009 13:29:21 -0300, Philip Semanchuk
> <philip at semanchuk.com> escribi?:
>> On Jul 6, 2009, at 12:10 PM, Diez B. Roggisch wrote:
>>> Philip Semanchuk wrote:
>>>
>>>> I can't figure out how to map a C variable of size_t via Python's
>>>> ctypes module.
>>>
>>> from ctypes import c_size_t
>>
>> D'oh! [slaps forehead]
>>
>> That will teach me to RTFM. [...] You'd be surprised at the amount  
>> of Googling I did without learning this on my own.
>
> Yep, seems like these terms in particular are hard to find.  
> Searching for
> +ctypes +size_t, the first "good" result comes only at page 3. Bad  
> luck...
> :(

Fortunately, through my ignorance I may provide enlightenment...this  
conversation is now hit #3 on page 1 =)

If I paste the URL here, will I create an infinite loop?
http://www.google.com/search?q=%2Bctypes+%2Bsize_t




From dnhkng at googlemail.com  Tue Jul  7 09:23:25 2009
From: dnhkng at googlemail.com (Dr Mephesto)
Date: Tue, 7 Jul 2009 06:23:25 -0700 (PDT)
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
Message-ID: <fc6b4e6a-5e89-4fed-914b-232fc6b1cf0e@h18g2000yqj.googlegroups.com>

Sure, I am learning Objective C already, but the syntax is really
unfriendly after python.

I think it really depends on the type of app you want to write.
Anything held back by network delays or that sits around waiting for
user input are perfectly acceptable target apps. If you need speed for
something really intensive, falling back to C is still much nicer than
coding in Objective C. I agree that having a certain basic
understanding of objective C is a must, but having the option to use a
coder-friendly language like Ruby or Python can cut development time
dramatically.

If Ruby can do it (and it generally slower than python), why can
Python also get a legal iPhone interpreter?



From deets at nospam.web.de  Tue Jul  7 09:23:34 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 07 Jul 2009 15:23:34 +0200
Subject: Tkinter.Canvas thread safety problem?
References: <mailman.2764.1246970677.8015.python-list@python.org>
Message-ID: <7bh0anF22udtoU1@mid.uni-berlin.de>

Zdenek Maxa wrote:

> Hello,
> 
> I have started a project using Tkinter. The application performs some
> regular checks in a thread and updates Canvas components. I have
> observed that sometimes the application hangs when it is about to call
> canvas.itemconfig() when the thread is about to terminate in the next
> loop.
> 
> Experimenting with this problem for a while, I have compiled a little
> example which always reproduces the problem. Commenting out the line 52
> (before canvas.itemconfig()), the example always finishes all right,
> having the delay there, it hangs.
> 
> I would like to ask if you could have a look at the snippet in the
> attachment and tell me if that is actually me doing something wrong or
> indeed Tkinter thread safety problem and what the workaround could be.
> 
> Could you please also comment on wxPython thread safety?
> 

As a rule of thumb, GUI-toolkits aren't threadsafe. Qt being a notable
exception to this rule.

There are various ways to cope with this, mostly through injecting events
into the event-queue of the main gui thread, or using timers.

This is also true for wx (google wx python threading for a plethora of
information on this)

For Tx, I dimly remember an "after" function that can be used to invoke
timer-based code. Use that to update aggregated data from the events.

Diez


From bruno.42.desthuilliers at websiteburo.invalid  Tue Jul  7 09:23:49 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Tue, 07 Jul 2009 15:23:49 +0200
Subject: Why re.match()?
In-Reply-To: <87prccsnrp.fsf@rudin.co.uk>
References: <h2g817$mjo$1@reader1.panix.com>	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1>	<h2hap5$qv8$2@reader1.panix.com>	<pan.2009.07.02.04.14.35@REMOVE.THIS.cybersource.com.au>	<h2i54b$eg3$1@reader1.panix.com>	<4a4e2227$0$7801$426a74cc@news.free.fr>	<h2tngh$12s$1@reader1.panix.com>	<4a5336a8$0$11315$426a74cc@news.free.fr>
	<87prccsnrp.fsf@rudin.co.uk>
Message-ID: <4a534c5e$0$414$426a74cc@news.free.fr>

Paul Rudin a ?crit :
> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
> 
>> kj a ?crit :
>>> In <4a4e2227$0$7801$426a74cc at news.free.fr> Bruno Desthuilliers <bruno.42.desthuilliers at websiteburo.invalid> writes:
>>>
>>>> kj a ?crit :
>>>> (snipo
>>>>> To have a special-case
>>>>> re.match() method in addition to a general re.search() method is
>>>>> antithetical to language minimalism,
>>>> FWIW, Python has no pretention to minimalism.
>>> Assuming that you mean by this that Python's authors have no such
>>> pretensions:
>>>
>>> "There is real value in having a small language."
>>>
>>> 			Guido van Rossum, 2007.07.03
>>> 			http://mail.python.org/pipermail/python-3000/2007-July/008663.html
>> There are some differences between "small" and "minimal"...
>>
> 
> There's also a difference between the language and its standard
> library.

Indeed.


From pdpinheiro at gmail.com  Tue Jul  7 09:37:02 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 06:37:02 -0700 (PDT)
Subject: Why re.match()?
References: <h2g817$mjo$1@reader1.panix.com>
	<Xns9C3BCA27ABC36duncanbooth@127.0.0.1> 
	<h2hap5$qv8$2@reader1.panix.com>
Message-ID: <d6d77204-3c1c-4374-92d1-8383bf5bc890@a7g2000yqk.googlegroups.com>

On Jul 2, 4:49?am, kj <no.em... at please.post> wrote:
> In <Xns9C3BCA27ABC36duncanbo... at 127.0.0.1> Duncan Booth <duncan.bo... at invalid.invalid> writes:
>
> >So, for example:
> >>>> re.compile("c").match("abcdef", 2)
> ><_sre.SRE_Match object at 0x0000000002C09B90>
> >>>> re.compile("^c").search("abcdef", 2)
>
> I find this unconvincing; with re.search alone one could simply
> do:
>
> >>> re.compile("^c").search("abcdef"[2:])

given large enough values of "abcdef", you just allocated several megs
for no good reason, when re.compile("c").match("abcdef", 2) would
process "abcdef" in-place.


From davea at ieee.org  Tue Jul  7 09:38:37 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 09:38:37 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <Xns9C4173416946Fduncanbooth@127.0.0.1>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>	<mailman.2753.1246941897.8015.python-list@python.org>
	<Xns9C4173416946Fduncanbooth@127.0.0.1>
Message-ID: <4A534FDD.8030105@ieee.org>

Duncan Booth wrote:
> Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:
>
>   
>> for, if, and return were common keywords in FORTRAN.
>>     
>
> Really? What does 'for' do in FORTRAN?
>
> P.S. Does FORTRAN actually have keywords these days? Back when I learned it 
> there was no such thing as a reserved word though for all I know they may 
> have since added them.
>
>   
The way I remember it (last used Fortran in 1970), DO was the looping 
construct, not FOR.  Naturally it was uppercase, as keypunches of the 
time didn't have an easy way to do lowercase.  (It was possible, you 
just had to use multi-punch, and a good memory for the appropriate 
0-12-11 prefixes).




From piet at cs.uu.nl  Tue Jul  7 09:41:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 15:41:46 +0200
Subject: Creating alot of class instances?
References: <078efee7-c96f-4075-8074-7b651c23cd86@y7g2000yqa.googlegroups.com>
	<mailman.2652.1246830168.8015.python-list@python.org>
	<22e6e4a0-7140-488a-b802-bb94754ff53b@c1g2000yqi.googlegroups.com>
	<006d4e86$0$9711$c3e8da3@news.astraweb.com>
	<comdnVhXl4M6bczXnZ2dnUVZ_g2dnZ2d@pdx.net>
	<006e79e9$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <m2ljn0d2zp.fsf@cs.uu.nl>

>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:

>SD> On Mon, 06 Jul 2009 05:47:18 -0700, Scott David Daniels wrote:
>>> Steven D'Aprano wrote:
>>>> ... That's the Wrong Way to do it --
>>>> you're using a screwdriver to hammer a nail....
>>> 
>>> Don't knock tool abuse (though I agree with you here). Sometimes tool
>>> abuse can produce good results.  For example, using hammers to drive
>>> screws for temporary strong holds led to making better nails.

>SD> Historically, nails were invented a long time before screws. Screws as 
>SD> fasteners weren't invented until the 1400s, nails were used thousands of 
>SD> years ago.

>SD> And hammering screws makes temporary *weak* holds, not strong, because 
>SD> the screw only touches the sides of the hole lightly. Unless the screw 
>SD> has been specifically designed to be hammered, hammering screws is pretty 
>SD> much the definition of incompetence and/or laziness!

In our language (Dutch, i.e. Guido's mother tongue) `American
screwdriver' is an expression meaning `hammer' :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nile_mcadams at yahoo.com  Tue Jul  7 09:45:12 2009
From: nile_mcadams at yahoo.com (Nile)
Date: Tue, 7 Jul 2009 06:45:12 -0700 (PDT)
Subject: Semi-Newbie needs a little help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
Message-ID: <97697cdc-e6b3-4277-b26e-d859ee4cd499@h31g2000yqd.googlegroups.com>

Thanks all for your help. I appreciate it.  The problem was in the
function.  A simple bug which I should have caught but I had my mental
blinders on and was sure the problem was outside the function.  The
answers have given me a lot to learn so thanks for that as well.


From __peter__ at web.de  Tue Jul  7 09:50:35 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 07 Jul 2009 15:50:35 +0200
Subject: Tkinter.Canvas thread safety problem?
References: <mailman.2764.1246970677.8015.python-list@python.org>
Message-ID: <h2vjq9$lb5$03$1@news.t-online.com>

Zdenek Maxa wrote:

> I would like to ask if you could have a look at the snippet in the
> attachment and tell me if that is actually me doing something wrong or
> indeed Tkinter thread safety problem and what the workaround could be.

http://effbot.org/zone/tkinter-threads.htm



From CHausberger at gmx.de  Tue Jul  7 09:59:49 2009
From: CHausberger at gmx.de (Claus Hausberger)
Date: Tue, 07 Jul 2009 15:59:49 +0200
Subject: Problem reading file with umlauts
Message-ID: <20090707135949.100950@gmx.net>

Hello

I have a text file with is encoding in Latin1 (ISO-8859-1). I can't change that as I do not create those files myself.

I have to read those files and convert the umlauts like ? to stuff like &oumol; as the text files should become html files.

I have this code:


#!/usr/bin/python
# -*- coding: latin1 -*-

import codecs

f = codecs.open('abc.txt', encoding='latin1')

for line in f:
    print line
    for c in line: 
        if c == "?":
            print "oe"
        else:
            print c


and I get this error message:

$ ./read.py
Abc

./read.py:11: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
  if c == "?":
A
b
c



Traceback (most recent call last):
  File "./read.py", line 9, in <module>
    print line
UnicodeEncodeError: 'ascii' codec can't encode characters in position 0-3: ordinal not in range(128)




I checked the web and tried several approaches but I also get some strange encoding errors.
Has anyone ever done this before? 
I am currently using Python 2.5 and may be able to use 2.6 but I cannot yet move to 3.1 as many libs we use don't yet work with Python 3.

any help more than welcome.  This has been driving me crazy for two days now.

best wishes

Claus
-- 
Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
f?r nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


From stefan_ml at behnel.de  Tue Jul  7 10:04:09 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 16:04:09 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <mailman.2774.1246975200.8015.python-list@python.org>
References: <mailman.2774.1246975200.8015.python-list@python.org>
Message-ID: <4a5355d9$0$31339$9b4e6d93@newsspool4.arcor-online.net>

Claus Hausberger wrote:
> Hello
> 
> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't change that as I do not create those files myself.
> 
> I have to read those files and convert the umlauts like ? to stuff like &oumol; as the text files should become html files.
> 
> I have this code:
> 
> 
> #!/usr/bin/python
> # -*- coding: latin1 -*-
> 
> import codecs
> 
> f = codecs.open('abc.txt', encoding='latin1')
> 
> for line in f:
>     print line
>     for c in line: 
>         if c == "?":

You are reading Unicode strings, so you have to compare it to a unicode
string as in

	if c == u"?":

>             print "oe"
>         else:
>             print c

Note that printing non-ASCII characters may not always work, depending on
your terminal.

Stefan


From sajmikins at gmail.com  Tue Jul  7 10:18:30 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 10:18:30 -0400
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
Message-ID: <50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>

On Mon, Jul 6, 2009 at 7:00 PM, <nacim_bravo at agilent.com> wrote:
> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment?
>
> Please let me know,
> nacim
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>

The answers to your first and third questions are, "yes" and "yes". :]
 (Generally speaking if something can be done by a computer it can be
done with python.)

As for your second question check out the "magnitude" package:

http://pypi.python.org/pypi/magnitude/   and
http://juanreyero.com/magnitude/

(That second link also has links to three other packages that deal
with units of measurement.)

Ii has units for the SI measurements, including volts and coulombs, so
you should be able to accomplish your goals with it.

The tricky thing is, as far as I can tell from the wikipedia entry
(http://en.wikipedia.org/wiki/Relative_static_permittivity),
"dielectric constant" seems to be a dimensionless number, i.e. C/C...
 I could be totally daft though.

HTH,
~Simon


From sajmikins at gmail.com  Tue Jul  7 10:22:48 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 07:22:48 -0700 (PDT)
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <c32e8f23-7a33-494e-8a92-fdd86403d627@d32g2000yqh.googlegroups.com>

On Jul 6, 6:02?pm, Michael Mossey <michaelmos... at gmail.com> wrote:
> On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>
> > On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>
> > > What is required in a python program to make sure it catches a ?
> > > control-
> > > c on the command-line? Do some i/o? The OS here is Linux.
>
> > You can use a try/except to catch a KeyboardInterrupt exception, or ?
> > you can trap it using the signal module:http://docs.python.org/library/signal.html
>
> > You want to trap SIGINT.
>
> > HTH
> > Philip
>
> Thanks to both of you. However, my question is also about whether I
> need to be doing i/o or some similar operation for my program to
> notice in any shape or form that Control-C has been pressed. In the
> past, I've written Python programs that go about their business
> ignoring Ctrl-C. Other programs respond to it immediately by exiting.
> I think the difference is that the latter programs are doing i/o. But
> I want to understand better what the "secret" is to responding to a
> ctrl-C in any shape or form.
>
> For example, does trapping SIGINT always work, regardless of what my
> process is doing?
>
> Thanks,
> Mike

Try some experiments. ;]


From aahz at pythoncraft.com  Tue Jul  7 10:41:59 2009
From: aahz at pythoncraft.com (Aahz)
Date: 7 Jul 2009 07:41:59 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2765.1246971084.8015.python-list@python.org>
Message-ID: <h2vmrn$3oh$1@panix3.panix.com>

In article <mailman.2765.1246971084.8015.python-list at python.org>,
Jean-Michel Pichavant  <jeanmichel at sequans.com> wrote:
>
>Can't we just calm down ? I'm really sorry my ignorance started this 
>thread, and my apologies go to Kj who's obviously more fluent in english 
>than me.
>I've never used sense in that way before, nor I've seen used by others 
>until now. However Kj is right, and my dictionary seems wrong 
>(wordreference.com). I've searched through others dictionaries and find 
>out this is actually applicable to functions. My bad.

You were not the first person to point out that "sense" is a poor
variable name.  Unless KJ is specifically using this code in the context
of a math class, I still think that "sense" is completely inappropriate.
Your English fluency is just fine.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From hubaghdadi at gmail.com  Tue Jul  7 10:46:18 2009
From: hubaghdadi at gmail.com (Hussein B)
Date: Tue, 7 Jul 2009 07:46:18 -0700 (PDT)
Subject: Remoting over SSH
Message-ID: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>

Hey,
I want to perform commands on a remote server over SSH.
What do I need?
Thanks.


From aahz at pythoncraft.com  Tue Jul  7 10:47:49 2009
From: aahz at pythoncraft.com (Aahz)
Date: 7 Jul 2009 07:47:49 -0700
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
Message-ID: <h2vn6l$klq$1@panix3.panix.com>

In article <85ljn0ej4h.fsf at agentultra.com>,
J Kenneth King  <james at agentultra.com> wrote:
>
>The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>device are already limited; running your program on top of an embedded
>Python interpreter would only be adding pressure to the constraints;
>even if it was an optimized interpreter.

<raised eyebrow>  Ten years ago, a 400MHz ARM processor would have been
fast, and it would have been running Python 1.5.2.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From sajmikins at gmail.com  Tue Jul  7 10:48:16 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 10:48:16 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <4A5344BE.2080006@sequans.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<4A5344BE.2080006@sequans.com>
Message-ID: <50f98a4c0907070748w39481ad9sed8ffba64b299dbc@mail.gmail.com>

On Tue, Jul 7, 2009 at 8:51 AM, Jean-Michel
Pichavant<jeanmichel at sequans.com> wrote:
> Steven D'Aprano wrote:
>>
>> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
>>
>>
>>>
>>> When people are fighting over things like `sense`, although sense may
>>> not be strictly wrong dictionary-wise, it smells of something burning...
>>>
>>
>> That would be my patience.
>>
>> I can't believe the direction this discussion has taken. Anybody sensible
>> would be saying "Oh wow, I've just learned a new meaning to the word, that's
>> great, I'm now less ignorant than I was a minute ago". But oh no, we mustn't
>> use a standard meaning to a word, heaven forbid we disturb people's
>> ignorance by teaching them something new.
>>
>> It's as simple as this: using `sense` as a variable name to record the
>> sense of a function is not a code smell, any more than using `flag` to
>> record a flag would be, or `sign` to record the sign of an object. If you
>> don't know the appropriate meanings of the words sense, flag or sign, learn
>> them, don't dumb down my language.
>>
>>
>
> Can't we just calm down ? I'm really sorry my ignorance started this thread,
> and my apologies go to Kj who's obviously more fluent in english than me.
> I've never used sense in that way before, nor I've seen used by others until
> now. However Kj is right, and my dictionary seems wrong (wordreference.com).
> I've searched through others dictionaries and find out this is actually
> applicable to functions. My bad.
>
> JM

Well met, sir.


From wuwei23 at gmail.com  Tue Jul  7 10:52:56 2009
From: wuwei23 at gmail.com (alex23)
Date: Tue, 7 Jul 2009 07:52:56 -0700 (PDT)
Subject: Remoting over SSH
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <f4a3012b-f462-425e-a081-cbf1b5f2a1fe@i4g2000prm.googlegroups.com>

On Jul 8, 12:46?am, Hussein B <hubaghd... at gmail.com> wrote:
> I want to perform commands on a remote server over SSH.
> What do I need?

Take a look at pexpect: http://pexpect.sourceforge.net/pexpect.html


From usernet at ilthio.net  Tue Jul  7 10:58:34 2009
From: usernet at ilthio.net (Tim Harig)
Date: Tue, 07 Jul 2009 14:58:34 GMT
Subject: Remoting over SSH
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <uoJ4m.6967$iz2.1440@nlpi070.nbdc.sbc.com>

On 2009-07-07, Hussein B <hubaghdadi at gmail.com> wrote:
> I want to perform commands on a remote server over SSH.
> What do I need?

catb.org/esr/faqs/smart-questions.html

There are many ways to remote using ssh.  If we know what you are trying to
do, maybe we could give you a better answer.  If you just want to open the
python interpreter interactively on another host you can do something like:

ssh -t user at host python

That will allow you send "commands" to the python interpeter.  You could
write a script and pipe it into the interpreter:

cat script.py | ssh -t user at host python

Maybe you want to open an ssh connection and send shell commands from a
python script.  You can do that using one of the popen2 functions:

http://docs.python.org/library/popen2.html


From nacim_bravo at agilent.com  Tue Jul  7 11:02:05 2009
From: nacim_bravo at agilent.com (nacim_bravo at agilent.com)
Date: Tue, 7 Jul 2009 09:02:05 -0600
Subject: Newbie needs help
In-Reply-To: <50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com>
	<50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>
Message-ID: <527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>

Hello Gurus,

Thank you for trying to help to my initial and not well written questions.  I will compile more detailed information and ask again.  Btw, I am giving a glimpse to: "How To Ask Questions The Smart Way".

nacim


-----Original Message-----
From: Simon Forman [mailto:sajmikins at gmail.com] 
Sent: Tuesday, July 07, 2009 7:19 AM
To: BRAVO,NACIM (A-Sonoma,ex1)
Cc: python-list at python.org
Subject: Re: Newbie needs help

On Mon, Jul 6, 2009 at 7:00 PM, <nacim_bravo at agilent.com> wrote:
> Dear Python gurus,
>
> If I'd like to set dielectric constant for the certain material, is it possible to do such in Python environment? If yes, how to do or what syntax can be used?
>
> Also, I'd like to get a simulation result, like voltage, is it possible to get this value in Python environment?
>
> Please let me know,
> nacim
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>

The answers to your first and third questions are, "yes" and "yes". :]
 (Generally speaking if something can be done by a computer it can be
done with python.)

As for your second question check out the "magnitude" package:

http://pypi.python.org/pypi/magnitude/   and
http://juanreyero.com/magnitude/

(That second link also has links to three other packages that deal
with units of measurement.)

Ii has units for the SI measurements, including volts and coulombs, so
you should be able to accomplish your goals with it.

The tricky thing is, as far as I can tell from the wikipedia entry
(http://en.wikipedia.org/wiki/Relative_static_permittivity),
"dielectric constant" seems to be a dimensionless number, i.e. C/C...
 I could be totally daft though.

HTH,
~Simon




From matt0177 at GMAIL.COM  Tue Jul  7 11:02:22 2009
From: matt0177 at GMAIL.COM (matt0177)
Date: Tue, 7 Jul 2009 08:02:22 -0700 (PDT)
Subject: Python Error from Apress book
In-Reply-To: <24364269.post@talk.nabble.com>
References: <24364269.post@talk.nabble.com>
Message-ID: <24374988.post@talk.nabble.com>


Adding the python before the command line didn't work at first, but upon
moving the files to the c:\python25 it worked like a champ. Thank you both
for the help. Very frustrating to run into stuff like this when you're first
trying to learn a knew language, it really throws off your momentum!
-- 
View this message in context: http://www.nabble.com/Python-Error-from-Apress-book-tp24364269p24374988.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From motoom at xs4all.nl  Tue Jul  7 11:05:32 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Tue, 07 Jul 2009 17:05:32 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <20090707135949.100950@gmx.net>
References: <20090707135949.100950@gmx.net>
Message-ID: <4A53643C.4020905@xs4all.nl>

Claus Hausberger wrote:

> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
> change that as I do not create those files myself. I have to read
> those files and convert the umlauts like ? to stuff like &oumol; as
> the text files should become html files.

umlaut-in.txt:
----
This file is contains data in the unicode
character set and is encoded with utf-8.
Viele R?hre. Macht spa?!  Ts?sch!


umlaut-in.txt hexdump:
----
000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e unicode..chara
000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and is
000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with utf
000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele R..hr
000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht spa..!
000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00  Ts..sch!.......


umlaut.py:
----
# -*- coding: utf-8 -*-
import codecs
text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
text=text.replace(u"?",u"oe")
text=text.replace(u"?",u"ss")
text=text.replace(u"?",u"ue")
of=open("umlaut-out.txt","w")
of.write(text)
of.close()


umlaut-out.txt:
----
This file is contains data in the unicode
character set and is encoded with utf-8.
Viele Roehre. Macht spass!  Tsuesch!


umlaut-out.txt hexdump:
----
000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e unicode...char
000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and is
000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with ut
000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele Roe
000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht spass
000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 !  Tsuesch!.....





-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html



From chengsoon.ong at inf.ethz.ch  Tue Jul  7 11:08:20 2009
From: chengsoon.ong at inf.ethz.ch (Cheng Soon Ong)
Date: Tue, 07 Jul 2009 17:08:20 +0200
Subject: automatic multiprocessing
Message-ID: <4A5364E4.4040607@inf.ethz.ch>

Hi all,

I'm trying to automate the use of multiprocessing when it is available. The 
setting I have is quite simple, with a for loop where the operations inside are 
independent of each other. Here's a bit of code. function_inputs is a list of 
dictionaries, each of which match the signature of function_handle.

     if multiprocessing_present:
         # Passing keyword arguments to map still doesn't work
         cpus = multiprocessing.Pool()
         function_outputs = cpus.map(function_handle, function_inputs)
     else:
         function_outputs = []
         for kwargs in function_inputs:
             cur_out = function_handle(**kwargs)
             function_outputs.append(cur_out)

Am I missing something here? I cannot seem to get map to pass on keyword arguments.

Thanks in advance,
Cheng Soon


From Scott.Daniels at Acm.Org  Tue Jul  7 11:11:27 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 07 Jul 2009 08:11:27 -0700
Subject: ISO library ref in printed form
In-Reply-To: <h2vcp9$66b$1@reader1.panix.com>
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <YrCdnen05dNx_s7XnZ2dnUVZ_sudnZ2d@pdx.net>

kj wrote:
> Does anyone know where I can buy the Python library reference in
> printed form?  (I'd rather not print the whole 1200+-page tome
> myself.)  I'm interested in both/either 2.6 and 3.0.

Personally, I'd get the new Beazley's Python Essential Reference,
which is due out "real soon now," and then use the provided docs
as a addon.  Also consider grabbing Gruet's "Python Quick Reference"
page.  When I was working in a printer site I printed the color
version of Gruet's page two-sided; it was neither too bulky nor
too sketchy for my needs (and he uses color to distinguish
version-to-version changes).
     http://rgruet.free.fr/
Sadly, I no longer work there, so my copy is gone. :-(

--Scott David Daniels
Scott.Daniels at Acm.Org


From tn.pablo at gmail.com  Tue Jul  7 11:12:38 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Tue, 7 Jul 2009 10:12:38 -0500
Subject: Newbie needs help
In-Reply-To: <527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906B23@cos-us-mb01.cos.agilent.com> 
	<50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com> 
	<527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>
Message-ID: <fdd00b510907070812y26e63ba0l75aff6d739738da8@mail.gmail.com>

On Tue, Jul 7, 2009 at 10:02, <nacim_bravo at agilent.com> wrote:
> Hello Gurus,
>
> Thank you for trying to help to my initial and not well written questions. ?I will compile more detailed information and ask again. ?Btw, I am giving a glimpse to: "How To Ask Questions The Smart Way".
>
> nacim

Give this one a try too: http://www.mikeash.com/getting_answers.html
It doesn't talk down to you...as much :P


-- 
Pablo Torres N.


From aahz at pythoncraft.com  Tue Jul  7 11:29:28 2009
From: aahz at pythoncraft.com (Aahz)
Date: 7 Jul 2009 08:29:28 -0700
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <h2vpko$jpk$1@panix3.panix.com>

In article <h2vcp9$66b$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>Does anyone know where I can buy the Python library reference in
>printed form?  (I'd rather not print the whole 1200+-page tome
>myself.)  I'm interested in both/either 2.6 and 3.0.

There used to be one for Python 2.1, but I can't tell whether it's ever
been updated because the website isn't responding:

http://wiki.python.org/moin/ReferenceBooks
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From davea at ieee.org  Tue Jul  7 11:44:44 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 11:44:44 -0400
Subject: Python Error from Apress book
In-Reply-To: <24374988.post@talk.nabble.com>
References: <24364269.post@talk.nabble.com> <24374988.post@talk.nabble.com>
Message-ID: <4A536D6C.4010308@ieee.org>

matt0177 wrote:
> Adding the python before the command line didn't work at first, but upon
> moving the files to the c:\python25 it worked like a champ. Thank you both
> for the help. Very frustrating to run into stuff like this when you're first
> trying to learn a knew language, it really throws off your momentum!
>   
I'm glad you got things working.  But you really shouldn't need to add 
your own files to the installation directory.  What you need is 
straightforward, but the details are Windows specific

The following is all at the command prompt, not inside Python.

You have a PATH environment variable, with various directories on it.  
Type it out using the PATH command.  Pick a location on it, and add a 
batch file we'll write below.  It's also possible to add a new directory 
to the PATH, using the control panel.  Normally, the first thing I do on 
a new machine is add two directories to the PATH, perhaps  c:\bin  and 
c:\bat.  The former is for the simple one-file utilities you accumulate 
over the years, and the latter is for batch files.  If you want to 
pursue this, let me know, and I'll give details.

Now that you've picked a location for your batch file, let's create it, 
calling it   Python25.bat   You could just call it Python.bat, but this 
way, you can have more than one Python installed, and choose between them.

The contents of Python25.bat are a single line:

@c:\python25\python.exe  %*

The leading @ says we don't wan the line echoed to the screen.  If 
you're unsure of yourself, you can leave it off till everything works 
well, then add it in.  The %* says to copy all the arguments you pass 
the batch file into the executable.

Once this batch file is stored in your PATH, you can just type something 
like:

      python25  myscript.py   arg1 arg2

or, to run the interpreter itself,
     python25

DaveA



From fetchinson at googlemail.com  Tue Jul  7 12:14:48 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Tue, 7 Jul 2009 09:14:48 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <4a531512$0$9355$426a74cc@news.free.fr>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
	<4a531512$0$9355$426a74cc@news.free.fr>
Message-ID: <fbe2e2100907070914m3c1f81d6i9b5165787263d1d2@mail.gmail.com>

> (snip)
>> and my point is that users
>> are most of time correct when they assume that something will work the
>> same way as in C.
>
> Oh, really ? They would surely be wrong if they'd expect the for loop to
> have any similarity with a C for loop, or - a *very* common error - if
> they'd expect assignment to work the same way as in C.

Yes, really. I wrote ".... most of the time ....." and not "all the time".

>> So I'd think that putting a warning in a FAQ or a Python Gotchas list
>> about ++n would be very useful for many users.
>
> Might eventually be useful, but I can't hardly recall of more than a
> couple threads on this topic in 8+ years.

I'm happy we agree.

Cheers,
Daniel

-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From sajmikins at gmail.com  Tue Jul  7 12:16:18 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 09:16:18 -0700 (PDT)
Subject: automatic multiprocessing
References: mailman.2782.1246980030.8015.python-list@python.org
Message-ID: <f72b0ed4-406d-4f9f-b629-0914143f6673@r33g2000yqn.googlegroups.com>

On Jul 7, 11:08?am, Cheng Soon Ong <chengsoon.... at inf.ethz.ch> wrote:
> Hi all,
>
> I'm trying to automate the use of multiprocessing when it is available. The
> setting I have is quite simple, with a for loop where the operations inside are
> independent of each other. Here's a bit of code. function_inputs is a list of
> dictionaries, each of which match the signature of function_handle.
>
> ? ? ?if multiprocessing_present:
> ? ? ? ? ?# Passing keyword arguments to map still doesn't work
> ? ? ? ? ?cpus = multiprocessing.Pool()
> ? ? ? ? ?function_outputs = cpus.map(function_handle, function_inputs)
> ? ? ?else:
> ? ? ? ? ?function_outputs = []
> ? ? ? ? ?for kwargs in function_inputs:
> ? ? ? ? ? ? ?cur_out = function_handle(**kwargs)
> ? ? ? ? ? ? ?function_outputs.append(cur_out)
>
> Am I missing something here? I cannot seem to get map to pass on keyword arguments.
>
> Thanks in advance,
> Cheng Soon

Pool.map() doesn't handle "**dict" keyword argument notation
automatically.  You could use a wrapper function like so:

cpus = multiprocessing.Pool()
def f(kwargs):
    return function_handle(**kwargs)
function_outputs = cpus.map(f, function_inputs)

(Note that f() could be defined outside the if statement if you're
going to use it often.)

HTH,
~Simon


From fetchinson at googlemail.com  Tue Jul  7 12:23:30 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Tue, 7 Jul 2009 09:23:30 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <4a531560$0$9355$426a74cc@news.free.fr>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
	<mailman.2754.1246945937.8015.python-list@python.org>
	<4a531560$0$9355$426a74cc@news.free.fr>
Message-ID: <fbe2e2100907070923n3caee67am2823d3b92209d6e4@mail.gmail.com>

>>>> Yes, there are plenty of languages other than Java and C, but the
>>>> influence of C is admittedly huge in Python. Why do you think loops
>>>> are called "for", conditionals "if" or "while", functions return via
>>>> "return", loops terminate via "break" and keep going via "continue"
>>>> and why is comparison written as "==", etc, etc? All of these are
>>>> coming from C (or an even earlier language) and my point is that users
>>> 	for, if, and return were common keywords in FORTRAN.
>>>
>>> 	Not to mention BASIC
>>>
>>> 	Both of which predate C
>>
>> Yes, hence my comment above, ".... coming from C (or an even earlier
>> language) ......".
>
>
> Mmm... Should we then claim that "the influence of FORTRAN is admittedly
> huge in Python" ?-)

Hmmmm, your comments reached a level of pedanticism beyond which I can
not follow :)
Seriously, ask Guido about the influence of C vs. fortran. Somewhere
you can find him quoted as saying that python was originally intended
to "bridge the gap between the shell and C". I've never heard him talk
about fortran.

But this academic discussion is honestly a little pointless. The OP
was referring to a expectation, coming from C, that is not fulfilled
in python. What's wrong with mentioning it somewhere for the sake of
helping C programmers?

Cheers,
Daniel


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From fetchinson at googlemail.com  Tue Jul  7 12:29:51 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Tue, 7 Jul 2009 09:29:51 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <4a531512$0$9355$426a74cc@news.free.fr>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
	<4a531512$0$9355$426a74cc@news.free.fr>
Message-ID: <fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>

>> and my point is that users
>> are most of time correct when they assume that something will work the
>> same way as in C.
>
> Oh, really ? They would surely be wrong if they'd expect the for loop to
> have any similarity with a C for loop, or - a *very* common error - if
> they'd expect assignment to work the same way as in C.

By the way, assignments in conditionals. Guido explicitly referred to
C when he forbade assignment in conditionals, citing common
typos/errors in C code such as if( x = 5 ){ .... } instead of if( x ==
5 ){ ..... }. So even he realized that warning people about different
usage in python and C is a good thing. Expectations from C work
sometimes, and sometimes they don't. In latter case a little warning
is useful.

Cheers,
Daniel

>> So I'd think that putting a warning in a FAQ or a Python Gotchas list
>> about ++n would be very useful for many users.
>
> Might eventually be useful, but I can't hardly recall of more than a
> couple threads on this topic in 8+ years.



-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From nagle at animats.com  Tue Jul  7 12:40:15 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 07 Jul 2009 09:40:15 -0700
Subject: Code that ought to run fast, but can't due to Python limitations.
In-Reply-To: <4a5310e7$0$31327$9b4e6d93@newsspool4.arcor-online.net>
References: <4a4f91f9$0$1587$742ec2ed@news.sonic.net>	<mailman.2631.1246781750.8015.python-list@python.org>
	<02605ef2$0$20657$c3e8da3@news.astraweb.com>
	<4a52eb5f$0$1663$742ec2ed@news.sonic.net>
	<4a5310e7$0$31327$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <4a537a11$0$1672$742ec2ed@news.sonic.net>

Stefan Behnel wrote:
> John Nagle wrote:
>>     I have a small web crawler robust enough to parse
>> real-world HTML, which can be appallingly bad.  I currently use
>> an extra-robust version of BeautifulSoup, and even that sometimes
>> blows up.  So I'm very interested in a new Python parser which supposedly
>> handles bad HTML in the same way browsers do.  But if it's slower
>> than BeautifulSoup, there's a problem.
> 
> Well, if performance matters in any way, you can always use lxml's
> blazingly fast parser first, possibly trying a couple of different
> configurations, and only if all fail, fall back to running html5lib over
> the same input. 

    Detecting "fail" is difficult.  A common problem is badly terminated
comments which eat most of the document if you follow the spec.  The
document seems to parse correctly, but most of it is missing.  The
HTML 5 spec actually covers things like

	<!This is a bogus SGML directive>

and treats it as a bogus comment.  (That's because HTML 5 doesn't
include general SGML; the only directive recognized is DOCTYPE.
Anything else after "<!" is treated as a token-level error.)

    So using an agreed-upon parsing method, in the form of html5lib,
is desirable, in that it should mimic browser behavior.

					John Nagle


From stefan_ml at behnel.de  Tue Jul  7 12:50:48 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 18:50:48 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <mailman.2780.1246979137.8015.python-list@python.org>
References: <20090707135949.100950@gmx.net>
	<mailman.2780.1246979137.8015.python-list@python.org>
Message-ID: <4a537ce8$0$30220$9b4e6d93@newsspool1.arcor-online.net>

Michiel Overtoom schrob:
> Viele R?hre. Macht spa?!  Ts?sch!

LOL! :)

Stefan


From dana_at_work at yahoo.com  Tue Jul  7 13:05:07 2009
From: dana_at_work at yahoo.com (dana)
Date: Tue, 7 Jul 2009 10:05:07 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
Message-ID: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>

I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
modules together. Although I don't have Python 2.5, I've been informed
the DBI module has been deprecated at 2.5. A few questions:

1) Although deprecated, will it work at all in 2.5? Does the fact that
it is deprecrated mean it has been removed entirely, or does Python
2.5 simply issuing a warning?

2) What do I use in place of DBI for my Python 2.4. scripts that
import modules DBI and ODBC together. I don't use DBI directly. It was
simply a dependency for the ODBC module as best I knew.

Thanks.

Dana


From python at mrabarnett.plus.com  Tue Jul  7 13:10:27 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 18:10:27 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<006da5a2$0$9711$c3e8da3@news.astraweb.com>	<mailman.2746.1246935242.8015.python-list@python.org>	<4a531512$0$9355$426a74cc@news.free.fr>
	<fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>
Message-ID: <4A538183.9020009@mrabarnett.plus.com>

Daniel Fetchinson wrote:
>>> and my point is that users
>>> are most of time correct when they assume that something will work the
>>> same way as in C.
>> Oh, really ? They would surely be wrong if they'd expect the for loop to
>> have any similarity with a C for loop, or - a *very* common error - if
>> they'd expect assignment to work the same way as in C.
> 
> By the way, assignments in conditionals. Guido explicitly referred to
> C when he forbade assignment in conditionals, citing common
> typos/errors in C code such as if( x = 5 ){ .... } instead of if( x ==
> 5 ){ ..... }. So even he realized that warning people about different
> usage in python and C is a good thing. Expectations from C work
> sometimes, and sometimes they don't. In latter case a little warning
> is useful.
> 
I wonder whether the problem with assignment in conditionals in C is due
to the assignment operator being "=". If it was ":=", would the error
still occur?


From douglas.packard at gmail.com  Tue Jul  7 13:34:17 2009
From: douglas.packard at gmail.com (weforgottenuno)
Date: Tue, 7 Jul 2009 10:34:17 -0700 (PDT)
Subject: Unable to get Tkinter menubar to appear under OS X
References: <3737fd18-4973-4cc3-914d-fbdefdbbb8a7@t10g2000vbg.googlegroups.com>
Message-ID: <6a9b0831-ce2e-417b-ab4b-419629d0a25d@u16g2000pru.googlegroups.com>

I'm having the same problem, though I am just using the pre-installed
python and tkinter versions that are on my OS X 10.5 computer, I did
not install them on my own. Any advice?

-Doug

On Jun 24, 9:22?am, Eric Winter <elwin... at verizon.net> wrote:
> Hi all. I've googled this issue several times and come up dry. Here's
> the situation:
>
> I have a X-windows build of Tkinter for Python built on an OS X
> machine (10.4 or 10.5, same issue). This is not the Aqua version of
> Tk, but Tk built from source using X-Window support. I also use a from-
> source build of Python, not the system Python. I don't like this
> arrangement, but project requirements (allegedly) dictate this
> approach.
>
> When I run any application using that copy of Tkinter and that copy of
> Python, everything seems to work fine except menus - the code which
> creates the menus runs, but no menus appear, either in the window or
> at the top of the screen.
>
> Am I required to use the Aqua version of Tk on OS X? If not, do I need
> to do something special on OS X when I built Tk and/or Python? Any
> hints here would be greatly appreciated.
>
> Thanks,
> Eric Winter
> Fermi Science Support Center
> NASA Goddard Space Flight Center



From piet at cs.uu.nl  Tue Jul  7 13:38:59 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 19:38:59 +0200
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com> <h2vn6l$klq$1@panix3.panix.com>
Message-ID: <m2eisscs0c.fsf@cs.uu.nl>

>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:

>A> In article <85ljn0ej4h.fsf at agentultra.com>,
>A> J Kenneth King  <james at agentultra.com> wrote:
>>> 
>>> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>>> device are already limited; running your program on top of an embedded
>>> Python interpreter would only be adding pressure to the constraints;
>>> even if it was an optimized interpreter.

>A> <raised eyebrow>  Ten years ago, a 400MHz ARM processor would have been
>A> fast, and it would have been running Python 1.5.2.

My first Python experience at home was on a 40MHz 80486 (Python 1.5.2 I
think). It was a bit slow :=(
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From hannarosie at gmail.com  Tue Jul  7 13:46:47 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Tue, 7 Jul 2009 10:46:47 -0700
Subject: Write matrix to text file
Message-ID: <564970db0907071046o60e927dao21cc0557f1fa2903@mail.gmail.com>

Hi,

I'm working with both python and matlab at the moment and I was wondering if
there is an efficient way to take a 2-D array (of 1s and 0s) in python and
write it to a text file such that matlab will be able to create a sparse
matrix from it later.

Thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/f0c1c374/attachment-0001.html>

From stefan_ml at behnel.de  Tue Jul  7 13:48:32 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 07 Jul 2009 19:48:32 +0200
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2rnoe$26s$5@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <4a538a71$0$30236$9b4e6d93@newsspool1.arcor-online.net>

Lawrence D'Oliveiro wrote:
> I wonder how many people have been tripped up by the fact that
> 
>     ++n
> 
> and
> 
>     --n
> 
> fail silently for numeric-valued n.

I doubt that there are many. Plus, you misspelled them from the more obvious

	n++

and

	n--

which *do* fail with a SyntaxError. I think I faintly remember trying those
in my early Python days and immediately went for "+=" when I saw them fail
(as I had expected).

Stefan


From robert.oschler at gmail.com  Tue Jul  7 14:01:17 2009
From: robert.oschler at gmail.com (roschler)
Date: Tue, 7 Jul 2009 11:01:17 -0700 (PDT)
Subject: Embedded Python : Why does thread lock here?
Message-ID: <00e8b4e8-5386-4f3d-b900-ab1ba41294f2@q40g2000prh.googlegroups.com>

I have the Python Intepreter embedded in a Delphi (Object Pascal)
program.  In the Python script shown below, I have a module that
creates a thread object and starts it.  The thread's run() call calls
a function called deleteOutputVariables() declared at the module
level.  In my code's first incarnation the thread's run() call would
deadlock when trying to call the deleteOutputVariables() function
declared at Module level.  I would never see the statement
"(deleteOutputVariables) Top of Call" printed to the screen.  I now
know that I must periodically call join() with a very fast time-out to
keep Python threads happy, and that solved the problem.  However I am
curious as to why it deadlocked at the deleteOutputVariables() call?
Is it because deleteOutputVariables() is declared at the module level
or because that function deletes module level variables?  If so why?

The code with the relevant parts excerpted is shown below, hopefully
the indents hold up.

Thanks,
Robert

----------------------------

# MODULE: PythonThreadTest.py

# FUNCTION: Delete the variables given in the list.
def deleteOutputVariables(theModule, theOutputVariablesListOfNames):
    try:
        print "(deleteOutputVariables) Top of call."
        for theOutputVariableName in theOutputVariablesListOfNames:
            if theModule.__dict__.has_key(theOutputVariableName):
                print "(Python::deleteOutputVariables) Deleting the
Output Variable named " + theOutputVariableName
                del theModule.__dict__[theOutputVariableName]
    except:
        print "(deleteOutputVariables) Exception occurred."

# Import needed system modules
import sys, os
from threading import Thread

# ----------------- BEGIN: THREAD class to execute robodanceCommand()
class threadRun(Thread):
    def __init__ (self, theJobID = None):
        Thread.__init__(self)
        self.jobCompleted = False
    # def: __init__
    def run(self):
        try:
        	# NOTE ---> This is where the thread locks if I don't call
join(0.001) in
        	#  my DELPHI (not Python) loop that waits on the thread to
complete.  Once
        	#  theNewThread.join() is called, execution resumes in
        	#  deleteOutputVariables() and the thread completes.
            deleteOutputVariables(Test_PYTHON, ["PyOut1"])

            # Let others know we are done.
            self.jobCompleted = True
        except Exception, exc:
            self.exceptionCaught = exc
            # Let others know we are done.
            self.jobCompleted = True
            print("(Python::threadRun) Exception occurred.")
        # end: try
    # def: run()
# ----------------- END: THREAD to execute robodanceCommand()

theNewThread = None
theNewThread = threadRun("TestThread")
theNewThread.start()


From pdpinheiro at gmail.com  Tue Jul  7 14:01:33 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:01:33 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>

On Jul 7, 2:16?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Mon, 06 Jul 2009 16:43:43 +0100, Tim Rowe wrote:
> > 2009/7/4 kj <no.em... at please.post>:
>
> >> Precisely. ?As I've stated elsewhere, this is an internal helper
> >> function, to be called only a few times under very well-specified
> >> conditions. ?The assert statements checks that these conditions are as
> >> intended. ?I.e. they are checks against the module writer's programming
> >> errors.
>
> > Good for you. I'm convinced that you have used the assertion
> > appropriately, and the fact that so many here are unable to see that
> > looks to me like a good case for teaching the right use of assertions.
> > For what it's worth, I read assertions at the beginning of a procedure
> > as part of the specification of the procedure, and I use them there in
> > order to document the procedure. An assertion in that position is for me
> > a statement to the user of the procedure "it's your responsibility to
> > make sure that you never call this procedure in such a way as to violate
> > these conditions". They're part of a contract, as somebody (maybe you)
> > pointed out.
>
> > As somebody who works in the safety-critical domain, it's refreshing to
> > see somebody teaching students to think about the circumstances in which
> > a procedure can legitimately be called. The hostility you've received to
> > that idea is saddening, and indicative of why there's so much buggy
> > software out there.
>
> LOL.
>
> Maybe the reason for "so much buggy software" is that people
> inappropriately use assert, thus changing the behaviour of code depending
> on whether it is run with the -O flag or not.
>
> I don't know what "hostility" you're seeing. The only hostility I'm
> seeing is from the OP, which is bizarre considering that he asked for
> advice and we gave it. What I see is a bunch of people concerned that the
> OP is teaching novices a bad habit, namely, using assert for error
> checking. He claims -- angrily and over and over again -- that in his
> code, the assertions should never fail. Great. Good for him for knowing
> when to use assert. (...)

But he doesn't.

He asserts:
    assert lo < hi
but then compares:
    sense = cmp(func(hi), func(lo))

sense can't ever be anything other than 1. I actually find it amusing
that this threat got to 50 posts of raving discussion about assertions
without anyone spotting that.

Personally, I think the code is an unreadable mess, but that's mostly
because of all the micro optimizations, not the generality of it.
Here's my unoptimized, but still equally generic, version:

def _binary_search(lo, hi, func, target, epsilon):
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    guess = (lo + hi) / 2.
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if func(guess) > target:
            hi = guess
        elif func(guess) < target:
            lo = guess
        elif lo == hi:
            return None
    return guess

This is a newbie course, right? A while True loop might be faster, but
it's all sorts of wrong for teaching newbies. Likewise, calculating a
midpoint as mid = (hi + lo) * .5 is an aberration in a beginner
environment. You want your students asking why you're calculating an
average, not asking why you're multiplying by 0.5. In the same vein, I
have no words for your target_plus/target_minus cleverness.

The right way to go about it, IMO, is to give them my version, let
them digest it, make all the necessary changes to it to turn it into
your (faster) version. Present benchmarks for both, then let the
readability/performance trade-off sink in. What you achieve with this
exercise is that, instead of making your students think "I have to
read that crud!?", they'll respect that ugly code is often the result
of eking out every last drop of performance from a program as you
possibly can.


From inky788 at gmail.com  Tue Jul  7 14:01:45 2009
From: inky788 at gmail.com (Inky 788)
Date: Tue, 7 Jul 2009 11:01:45 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com> 
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net> 
	<mailman.2759.1246954003.8015.python-list@python.org>
Message-ID: <59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>

On Jul 7, 4:06?am, Chris Withers <ch... at simplistix.co.uk> wrote:
> David Lyon wrote:
>
> > What hasn't happened is enough testing of pypi packages and installing
> > with setuptools/pip/enstall from pypi.
>
> What needs testing?
>
> More important for me is which of these has the most active development
> community. How do we judge that?

Currently, distutils itself is being actively developed. More info
about this here: http://tarekziade.wordpress.com/

My (albeit anonymous) advice is: use distutils. Manually download
packages as-needed from PyPI and install manually using standard
distutils.

Read more about distutils here http://wiki.python.org/moin/Distutils
and of course in the Python docs.

If you want to contribute, my first guess would be that Tarek could
use help writing tests (but I don't know what distutils coverage looks
like at the moment).

When Tarek says, "For package installation that takes care of
dependencies, uninstall, etc., use $tool", then I'll start using
$tool. Until then, it's just straight distutils for me.


From http  Tue Jul  7 14:06:59 2009
From: http (Paul Rubin)
Date: 07 Jul 2009 11:06:59 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
Message-ID: <7xab3gz7ss.fsf@ruckus.brouhaha.com>

pdpi <pdpinheiro at gmail.com> writes:
> Personally, I think the code is an unreadable mess, but that's mostly
> because of all the micro optimizations, not the generality of it.
> Here's my unoptimized, but still equally generic, version:

That version doesn't use "sense" inside the binary search, i.e. it
relies on the function being monotonically increasing.


From andreengels at gmail.com  Tue Jul  7 14:26:45 2009
From: andreengels at gmail.com (Andre Engels)
Date: Tue, 7 Jul 2009 20:26:45 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
Message-ID: <6faf39c90907071126o5c774a79h4de2921fb3af205a@mail.gmail.com>

On Tue, Jul 7, 2009 at 8:01 PM, pdpi<pdpinheiro at gmail.com> wrote:

> He asserts:
> ? ?assert lo < hi
> but then compares:
> ? ?sense = cmp(func(hi), func(lo))
>
> sense can't ever be anything other than 1.

It can - there is no necessity that func is monotonically increasing.

-- 
Andr? Engels, andreengels at gmail.com


From pdpinheiro at gmail.com  Tue Jul  7 14:30:42 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:30:42 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> 
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<mailman.2789.1246991214.8015.python-list@python.org>
Message-ID: <bdcef469-2d7e-4a7f-bfe5-2a2bcf9a5b91@a36g2000yqc.googlegroups.com>

On Jul 7, 7:26?pm, Andre Engels <andreeng... at gmail.com> wrote:
> On Tue, Jul 7, 2009 at 8:01 PM, pdpi<pdpinhe... at gmail.com> wrote:
> > He asserts:
> > ? ?assert lo < hi
> > but then compares:
> > ? ?sense = cmp(func(hi), func(lo))
>
> > sense can't ever be anything other than 1.
>
> It can - there is no necessity that func is monotonically increasing.
>
> --
> Andr? Engels, andreeng... at gmail.com

Yes, I realized that as I was walking home.

In other news, some of you may be interested in my seminar in advanced
foot-in-mouth placement.


From pdpinheiro at gmail.com  Tue Jul  7 14:31:39 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:31:39 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
Message-ID: <1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>

On Jul 7, 7:06?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> pdpi <pdpinhe... at gmail.com> writes:
> > Personally, I think the code is an unreadable mess, but that's mostly
> > because of all the micro optimizations, not the generality of it.
> > Here's my unoptimized, but still equally generic, version:
>
> That version doesn't use "sense" inside the binary search, i.e. it
> relies on the function being monotonically increasing.

You're right, make that:

def _binary_search(lo, hi, func, target, epsilon):
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    guess = (lo + hi) / 2.
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if sense * func(guess) > target:
            hi = guess
        elif sense * func(guess) < target:
            lo = guess
        elif lo == hi:
            return None
    return guess

Seems I had a serious brain cramp while posting that...


From pdpinheiro at gmail.com  Tue Jul  7 14:51:59 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 11:51:59 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
	<1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>
Message-ID: <1f09e856-bd04-4d27-bf51-5d67953a7e13@y7g2000yqa.googlegroups.com>

On Jul 7, 7:31?pm, pdpi <pdpinhe... at gmail.com> wrote:
> On Jul 7, 7:06?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>
> > pdpi <pdpinhe... at gmail.com> writes:
> > > Personally, I think the code is an unreadable mess, but that's mostly
> > > because of all the micro optimizations, not the generality of it.
> > > Here's my unoptimized, but still equally generic, version:
>
> > That version doesn't use "sense" inside the binary search, i.e. it
> > relies on the function being monotonically increasing.
>
> You're right, make that:
>
> def _binary_search(lo, hi, func, target, epsilon):
> ? ? sense = cmp(func(hi), func(lo))
> ? ? if sense == 0:
> ? ? ? ? return None
> ? ? guess = (lo + hi) / 2.
> ? ? while abs(func(guess) - target) > epsilon:
> ? ? ? ? guess = (lo + hi) / 2.
> ? ? ? ? if sense * func(guess) > target:
> ? ? ? ? ? ? hi = guess
> ? ? ? ? elif sense * func(guess) < target:
> ? ? ? ? ? ? lo = guess
> ? ? ? ? elif lo == hi:
> ? ? ? ? ? ? return None
> ? ? return guess
>
> Seems I had a serious brain cramp while posting that...

Actually, scratch that.

def _binary_search(lo, hi, func, target, epsilon):
    sense = cmp(func(hi), func(lo))
    if sense == 0:
        return None
    guess = (lo + hi) / 2.
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if sense * func(guess) > sense * target:
            hi = guess
        elif sense * func(guess) < sense * target:
            lo = guess
        elif lo == hi:
            return None
    return guess


From CHausberger at gmx.de  Tue Jul  7 15:00:46 2009
From: CHausberger at gmx.de (Claus Hausberger)
Date: Tue, 07 Jul 2009 21:00:46 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <4A53643C.4020905@xs4all.nl>
References: <20090707135949.100950@gmx.net> <4A53643C.4020905@xs4all.nl>
Message-ID: <20090707190046.152740@gmx.net>

Thanks a lot. Now I am one step further but I get another strange error:

Traceback (most recent call last):
  File "./read.py", line 12, in <module>
    of.write(text)
UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in position 0: ordinal not in range(128)

according to google ufeff has something to do with byte order.

I use an Linux system, maybe this helps to find the error.

Claus

> Claus Hausberger wrote:
> 
> > I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
> > change that as I do not create those files myself. I have to read
> > those files and convert the umlauts like ? to stuff like &oumol; as
> > the text files should become html files.
> 
> umlaut-in.txt:
> ----
> This file is contains data in the unicode
> character set and is encoded with utf-8.
> Viele R?hre. Macht spa?!  Ts?sch!
> 
> 
> umlaut-in.txt hexdump:
> ----
> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e unicode..chara
> 000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and is
> 000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with utf
> 000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele R..hr
> 000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht spa..!
> 000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00  Ts..sch!.......
> 
> 
> umlaut.py:
> ----
> # -*- coding: utf-8 -*-
> import codecs
> text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
> text=text.replace(u"?",u"oe")
> text=text.replace(u"?",u"ss")
> text=text.replace(u"?",u"ue")
> of=open("umlaut-out.txt","w")
> of.write(text)
> of.close()
> 
> 
> umlaut-out.txt:
> ----
> This file is contains data in the unicode
> character set and is encoded with utf-8.
> Viele Roehre. Macht spass!  Tsuesch!
> 
> 
> umlaut-out.txt hexdump:
> ----
> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e unicode...char
> 000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and is
> 000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with ut
> 000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele Roe
> 000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht spass
> 000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 !  Tsuesch!.....
> 
> 
> 
> 
> 
> -- 
> "The ability of the OSS process to collect and harness
> the collective IQ of thousands of individuals across
> the Internet is simply amazing." - Vinod Valloppillil
> http://www.catb.org/~esr/halloween/halloween4.html

-- 
Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
f?r nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


From davea at ieee.org  Tue Jul  7 15:04:27 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 15:04:27 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
Message-ID: <4A539C3B.3040508@ieee.org>

pdpi wrote:
> On Jul 7, 2:16 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>   
>> On Mon, 06 Jul 2009 16:43:43 +0100, Tim Rowe wrote:
>>     
>>> 2009/7/4 kj <no.em... at please.post>:
>>>       
>>>> Precisely.  As I've stated elsewhere, this is an internal helper
>>>> function, to be called only a few times under very well-specified
>>>> conditions.  The assert statements checks that these conditions are as
>>>> intended.  I.e. they are checks against the module writer's programming
>>>> errors.
>>>>         
>>> Good for you. I'm convinced that you have used the assertion
>>> appropriately, and the fact that so many here are unable to see that
>>> looks to me like a good case for teaching the right use of assertions.
>>> For what it's worth, I read assertions at the beginning of a procedure
>>> as part of the specification of the procedure, and I use them there in
>>> order to document the procedure. An assertion in that position is for me
>>> a statement to the user of the procedure "it's your responsibility to
>>> make sure that you never call this procedure in such a way as to violate
>>> these conditions". They're part of a contract, as somebody (maybe you)
>>> pointed out.
>>>       
>>> As somebody who works in the safety-critical domain, it's refreshing to
>>> see somebody teaching students to think about the circumstances in which
>>> a procedure can legitimately be called. The hostility you've received to
>>> that idea is saddening, and indicative of why there's so much buggy
>>> software out there.
>>>       
>> LOL.
>>
>> Maybe the reason for "so much buggy software" is that people
>> inappropriately use assert, thus changing the behaviour of code depending
>> on whether it is run with the -O flag or not.
>>
>> I don't know what "hostility" you're seeing. The only hostility I'm
>> seeing is from the OP, which is bizarre considering that he asked for
>> advice and we gave it. What I see is a bunch of people concerned that the
>> OP is teaching novices a bad habit, namely, using assert for error
>> checking. He claims -- angrily and over and over again -- that in his
>> code, the assertions should never fail. Great. Good for him for knowing
>> when to use assert. (...)
>>     
>
> But he doesn't.
>
> He asserts:
>     assert lo < hi
> but then compares:
>     sense =mp(func(hi), func(lo))
>
> sense can't ever be anything other than 1. I actually find it amusing
> that this threat got to 50 posts of raving discussion about assertions
> without anyone spotting that.
>
>   
That's because the assert and the comparison are unrelated to each 
other.  If the function is monotonically decreasing, then by definition 
lo<hi would guarantee that  func(lo)>= func(hi), which would yield a 
sense of 0 or -1.

Trivial example of monotonically decreasing:
    def func(inp):
         return 53.0 - inp

> Personally, I think the code is an unreadable mess, but that's mostly
> because of all the micro optimizations, not the generality of it.
> Here's my unoptimized, but still equally generic, version:
>
> def _binary_search(lo, hi, func, target, epsilon):
>     sense =mp(func(hi), func(lo))
>     if sense =0:
>         return None
>     guess =lo + hi) / 2.
>     while abs(func(guess) - target) > epsilon:
>         guess =lo + hi) / 2.
>         if func(guess) > target:
>             hi =uess
>         elif func(guess) < target:
>             lo =uess
>         elif lo =hi:
>             return None
>     return guess
>
>   
And of course your clarified function will fail if the func is 
monotonically decreasing.

I still think that rather than using sense in the loop, one should 
simply swap lo and hi, and continue.
> This is a newbie course, right? A while True loop might be faster, but
> it's all sorts of wrong for teaching newbies. Likewise, calculating a
> midpoint as mid =hi + lo) * .5 is an aberration in a beginner
> environment. You want your students asking why you're calculating an
> average, not asking why you're multiplying by 0.5. In the same vein, I
> have no words for your target_plus/target_minus cleverness.
>
> The right way to go about it, IMO, is to give them my version, let
> them digest it, make all the necessary changes to it to turn it into
> your (faster) version. Present benchmarks for both, then let the
> readability/performance trade-off sink in. What you achieve with this
> exercise is that, instead of making your students think "I have to
> read that crud!?", they'll respect that ugly code is often the result
> of eking out every last drop of performance from a program as you
> possibly can.
>
>   
(untested)

def _binary_search(lo, hi, func, target, epsilon):
    """ lo, hi  are floats representing the desired range of input values to func()
        func() is a function that takes a float argument, and returns a float result
        target is the desired result value of func()
        epsilon is the allowable error compared to target.  If set too small, this function will fail by returning None
        precondition:  func is monotonic over the range of floating point inputs from lo to hi """
        return a float value between lo and hi (inclusive) which yields approximately target
    if func(lo) > func(hi):
        lo, hi = hi, lo
    if not (func(lo) <= target <= func(hi)):
        return None                     #function doesn't have target value within the input range
    guess = lo
    while abs(func(guess) - target) > epsilon:
        guess = (lo + hi) / 2.
        if func(guess) > target:
            hi = guess
        elif func(guess) < target:
            lo = guess
        elif lo == hi:
            return None            #function is too steep to have a value within epsilon
    return guess

The reason for the "too steep" condition is that with a finite 
resolution for 'guess'  epsilon could be enough smaller than target as 
to make a result impossible.  For example, if the slope is 45 degrees, 
this happens when epsilon is about 2**51 smaller.




From pdpinheiro at gmail.com  Tue Jul  7 15:10:59 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 7 Jul 2009 12:10:59 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<mailman.2791.1246993486.8015.python-list@python.org>
Message-ID: <51f115a9-3e03-49f8-a340-4969133488cf@t33g2000yqe.googlegroups.com>

On Jul 7, 8:04?pm, Dave Angel <da... at ieee.org> wrote:
> And of course your clarified function will fail if the func is
> monotonically decreasing.

yeah, I eventually realized that and corrected it... And the assert()/
cmp() confusion too. I blame lack of sleep.

The whole sign/sense thing left a really bad taste in my mouth,
though, and the swapping lo and hi suggestion of yours seems like the
neatest solution presented.


From davea at ieee.org  Tue Jul  7 15:17:42 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 07 Jul 2009 15:17:42 -0400
Subject: Python Error from Apress book
In-Reply-To: <8e2cbd660907071048p3a7c3bf9r22026712bf9bc3e4@mail.gmail.com>
References: <24364269.post@talk.nabble.com> <24374988.post@talk.nabble.com>	
	<4A536D6C.4010308@ieee.org>
	<8e2cbd660907071048p3a7c3bf9r22026712bf9bc3e4@mail.gmail.com>
Message-ID: <4A539F56.9070109@ieee.org>

Matthew Edmondson wrote:
> Thanks a ton for the help. At first adding the path didn't work, but after
> restarting my computer, ran like a champ :)
>
> Hopefully I can get decent with this language one day!
>
>   
All you needed was to restart the DOS-box (Command Prompt), after you 
did the control-panel thing.  Those changes don't affect currently 
running processes.

.
By the way, those "standalone executables" could very well be python 
scripts.  Except for input redirection, all my single-file scripts work 
fine stored there.  And if you add  .py and .pyw to the PATHEXT 
environment variable, you can run them without extension, so they're 
pretty much interchangeable with .exe files.

So I have a script called digest.py, and I run it from a directory I 
want to analyze, by just typing
    digest  .




From dudeja.rajat at gmail.com  Tue Jul  7 15:31:07 2009
From: dudeja.rajat at gmail.com (dudeja.rajat at gmail.com)
Date: Wed, 8 Jul 2009 01:01:07 +0530
Subject: Check file is locked?
Message-ID: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>

How to check if a particular file is locked by some application? (i.e. the
file is opened by some application)?

-- 
Regrads,
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/b78d6a0f/attachment-0001.html>

From no.email at please.post  Tue Jul  7 15:37:20 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 19:37:20 +0000 (UTC)
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com> <h2vpko$jpk$1@panix3.panix.com>
Message-ID: <h3085g$c0m$1@reader1.panix.com>

In <h2vpko$jpk$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>In article <h2vcp9$66b$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>
>>Does anyone know where I can buy the Python library reference in
>>printed form?  (I'd rather not print the whole 1200+-page tome
>>myself.)  I'm interested in both/either 2.6 and 3.0.

>There used to be one for Python 2.1, but I can't tell whether it's ever
>been updated because the website isn't responding:

>http://wiki.python.org/moin/ReferenceBooks

Hmmm.  That's a shame.  How is one supposed to keep it under one's
pillow???

kj



From no.email at please.post  Tue Jul  7 15:38:32 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 19:38:32 +0000 (UTC)
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com>
	<YrCdnen05dNx_s7XnZ2dnUVZ_sudnZ2d@pdx.net>
Message-ID: <h3087o$c0m$2@reader1.panix.com>

In <YrCdnen05dNx_s7XnZ2dnUVZ_sudnZ2d at pdx.net> Scott David Daniels <Scott.Daniels at Acm.Org> writes:

>Also consider grabbing Gruet's "Python Quick Reference" page.

Not quite what I had in mind, but handy all the same.  Thanks.

kj


From pruebauno at latinmail.com  Tue Jul  7 15:51:26 2009
From: pruebauno at latinmail.com (nn)
Date: Tue, 7 Jul 2009 12:51:26 -0700 (PDT)
Subject: library search path when compiling python
Message-ID: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>

I am trying to compile python with ssl support but the libraries are
not in /usr/lib but in /opt/freeware/lib. How do I add that folder to
the default library search path?

It looks like configure --libdir=DIR might do the job but I don't want
to replace the default lib search path, just add an additional folder
to it.


From no.email at please.post  Tue Jul  7 16:04:46 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 20:04:46 +0000 (UTC)
Subject: tough-to-explain Python
Message-ID: <h309ot$bii$1@reader1.panix.com>



I'm having a hard time coming up with a reasonable way to explain
certain things to programming novices.

Consider the following interaction sequence:

>>> def eggs(some_int, some_list, some_tuple):
...     some_int += 2
...     some_list += [2]
...     some_tuple += (2,)
...
>>> x = 42
>>> y = (42,) 
>>> z = [42] 
>>> eggs(x, y, z)
>>> x
42
>>> y
(42,)
>>> z
[42, 2] 
>>> 

How do I explain to rank beginners (no programming experience at
all) why x and y remain unchanged above, but not z?

Or consider this one:

>>> ham = [1, 2, 3, 4]
>>> spam = (ham,)
>>> spam
([1, 2, 3, 4],)
>>> spam[0] is ham
True
>>> spam[0] += [5]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'tuple' object does not support item assignment
>>> ham += [5]
>>> spam
([1, 2, 3, 4, 5, 5],)
>>> 

What do you say to that?

I can come up with much mumbling about pointers and stacks and
heaps and much hand-waving about the underlying this-and-that, but
nothing that sounds even remotely illuminating.

Your suggestions would be much appreciated!

TIA!

kj


From lists at cheimes.de  Tue Jul  7 16:06:01 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 07 Jul 2009 22:06:01 +0200
Subject: library search path when compiling python
In-Reply-To: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>
References: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>
Message-ID: <4A53AAA9.9060307@cheimes.de>

nn wrote:
> I am trying to compile python with ssl support but the libraries are
> not in /usr/lib but in /opt/freeware/lib. How do I add that folder to
> the default library search path?
> 
> It looks like configure --libdir=DIR might do the job but I don't want
> to replace the default lib search path, just add an additional folder
> to it.

You didn't mention your OS. On Linux you can set the environment
variable LD_RUN_PATH prior to compiling Python. The env var sets the
rpath for the linker. See man ld(1) for details.

Christian


From lists at cheimes.de  Tue Jul  7 16:07:32 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 07 Jul 2009 22:07:32 +0200
Subject: Check file is locked?
In-Reply-To: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
Message-ID: <h309u4$901$1@ger.gmane.org>

dudeja.rajat at gmail.com wrote:
> How to check if a particular file is locked by some application? (i.e. the
> file is opened by some application)?

It depends on your operating system. By the way most operating systems
don't lock a file when it's opened for reading or writing or even executed.

Christian



From clp2 at rebertia.com  Tue Jul  7 16:08:50 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 7 Jul 2009 13:08:50 -0700
Subject: tough-to-explain Python
In-Reply-To: <h309ot$bii$1@reader1.panix.com>
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <50697b2c0907071308u375c81edt49fd2d1a2f6c7c34@mail.gmail.com>

On Tue, Jul 7, 2009 at 1:04 PM, kj<no.email at please.post> wrote:
>
>
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
> Consider the following interaction sequence:
>
>>>> def eggs(some_int, some_list, some_tuple):
> ... ? ? some_int += 2
> ... ? ? some_list += [2]
> ... ? ? some_tuple += (2,)
> ...
>>>> x = 42
>>>> y = (42,)
>>>> z = [42]
>>>> eggs(x, y, z)
>>>> x
> 42
>>>> y
> (42,)
>>>> z
> [42, 2]
>>>>
>
> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?
>
> Or consider this one:
>
>>>> ham = [1, 2, 3, 4]
>>>> spam = (ham,)
>>>> spam
> ([1, 2, 3, 4],)
>>>> spam[0] is ham
> True
>>>> spam[0] += [5]
> Traceback (most recent call last):
> ?File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
>>>> ham += [5]
>>>> spam
> ([1, 2, 3, 4, 5, 5],)
>>>>
>
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!

You might find the following helpful (partially):
http://effbot.org/zone/call-by-object.htm

Cheers,
Chris
-- 
http://blog.rebertia.com


From kevin.p.dwyer at gmail.com  Tue Jul  7 16:11:17 2009
From: kevin.p.dwyer at gmail.com (Kevin Dwyer)
Date: Tue, 7 Jul 2009 20:11:17 +0000 (UTC)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
Message-ID: <h30a55$88n$1@ger.gmane.org>

Hello,

I think this is discussed PEP 249 - see the "major changes" section.

http://www.python.org/dev/peps/pep-0249/

Kev

On Tue, 07 Jul 2009 10:05:07 -0700, dana wrote:

> I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
> modules together. Although I don't have Python 2.5, I've been informed
> the DBI module has been deprecated at 2.5. A few questions:
> 
> 1) Although deprecated, will it work at all in 2.5? Does the fact that
> it is deprecrated mean it has been removed entirely, or does Python 2.5
> simply issuing a warning?
> 
> 2) What do I use in place of DBI for my Python 2.4. scripts that import
> modules DBI and ODBC together. I don't use DBI directly. It was simply a
> dependency for the ODBC module as best I knew.
> 
> Thanks.
> 
> Dana




From deets at nospam.web.de  Tue Jul  7 16:15:40 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 07 Jul 2009 22:15:40 +0200
Subject: ISO library ref in printed form
In-Reply-To: <h3085g$c0m$1@reader1.panix.com>
References: <h2vcp9$66b$1@reader1.panix.com> <h2vpko$jpk$1@panix3.panix.com>
	<h3085g$c0m$1@reader1.panix.com>
Message-ID: <7bhoncF23eocqU1@mid.uni-berlin.de>

kj schrieb:
> In <h2vpko$jpk$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:
> 
>> In article <h2vcp9$66b$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>> Does anyone know where I can buy the Python library reference in
>>> printed form?  (I'd rather not print the whole 1200+-page tome
>>> myself.)  I'm interested in both/either 2.6 and 3.0.
> 
>> There used to be one for Python 2.1, but I can't tell whether it's ever
>> been updated because the website isn't responding:
> 
>> http://wiki.python.org/moin/ReferenceBooks
> 
> Hmmm.  That's a shame.  How is one supposed to keep it under one's
> pillow???


That's what netbooks were created for...

Diez


From piet at cs.uu.nl  Tue Jul  7 16:37:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 22:37:56 +0200
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <m2r5wsb55n.fsf@cs.uu.nl>

>>>>> kj <no.email at please.post> (kj) wrote:

>kj> Does anyone know where I can buy the Python library reference in
>kj> printed form?  (I'd rather not print the whole 1200+-page tome
>kj> myself.)  I'm interested in both/either 2.6 and 3.0.

Maybe you can have a copy printed at lulu.com. It would even be nicer if
the PSF would offer them at lulu. They could even make some money from
it if enough copies would be sold..
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at mrabarnett.plus.com  Tue Jul  7 16:40:20 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 07 Jul 2009 21:40:20 +0100
Subject: Problem reading file with umlauts
In-Reply-To: <20090707190046.152740@gmx.net>
References: <20090707135949.100950@gmx.net> <4A53643C.4020905@xs4all.nl>
	<20090707190046.152740@gmx.net>
Message-ID: <4A53B2B4.9090409@mrabarnett.plus.com>

Claus Hausberger wrote:
> Thanks a lot. Now I am one step further but I get another strange error:
> 
> Traceback (most recent call last):
>   File "./read.py", line 12, in <module>
>     of.write(text)
> UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in position 0: ordinal not in range(128)
> 
> according to google ufeff has something to do with byte order.
> 
> I use an Linux system, maybe this helps to find the error.
> 
'text' contains Unicode, but you're writing it to a file that's not
opened for Unicode. Either open the output file for Unicode:

     of = codecs.open("umlaut-out.txt", "w", encoding="latin1")

or encode the text before writing:

     text = text.encode("latin1")

(I'm assuming you want the output file to be in Latin1.)

> 
>> Claus Hausberger wrote:
>>
>>> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
>>> change that as I do not create those files myself. I have to read
>>> those files and convert the umlauts like ? to stuff like &oumol; as
>>> the text files should become html files.
>> umlaut-in.txt:
>> ----
>> This file is contains data in the unicode
>> character set and is encoded with utf-8.
>> Viele R?hre. Macht spa?!  Ts?sch!
>>
>>
>> umlaut-in.txt hexdump:
>> ----
>> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
>> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
>> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e unicode..chara
>> 000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and is
>> 000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with utf
>> 000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele R..hr
>> 000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht spa..!
>> 000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00  Ts..sch!.......
>>
>>
>> umlaut.py:
>> ----
>> # -*- coding: utf-8 -*-
>> import codecs
>> text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
>> text=text.replace(u"?",u"oe")
>> text=text.replace(u"?",u"ss")
>> text=text.replace(u"?",u"ue")
>> of=open("umlaut-out.txt","w")
>> of.write(text)
>> of.close()
>>
>>
>> umlaut-out.txt:
>> ----
>> This file is contains data in the unicode
>> character set and is encoded with utf-8.
>> Viele Roehre. Macht spass!  Tsuesch!
>>
>>
>> umlaut-out.txt hexdump:
>> ----
>> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is con
>> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in th
>> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e unicode...char
>> 000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and is
>> 000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with ut
>> 000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele Roe
>> 000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht spass
>> 000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 !  Tsuesch!.....
>>
>>
>>
>>
>>
>> -- 
>> "The ability of the OSS process to collect and harness
>> the collective IQ of thousands of individuals across
>> the Internet is simply amazing." - Vinod Valloppillil
>> http://www.catb.org/~esr/halloween/halloween4.html
> 



From piet at cs.uu.nl  Tue Jul  7 16:53:13 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 07 Jul 2009 22:53:13 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <m2my7gb4g6.fsf@cs.uu.nl>

>>>>> kj <no.email at please.post> (k) wrote:

>k> I'm having a hard time coming up with a reasonable way to explain
>k> certain things to programming novices.

>k> Consider the following interaction sequence:

>>>>> def eggs(some_int, some_list, some_tuple):
>k> ...     some_int += 2
>k> ...     some_list += [2]
>k> ...     some_tuple += (2,)
>k> ...
>>>>> x = 42
>>>>> y = (42,) 
>>>>> z = [42] 
>>>>> eggs(x, y, z)
>>>>> x
>k> 42
>>>>> y
>k> (42,)
>>>>> z
>k> [42, 2] 
>>>>> 

>k> How do I explain to rank beginners (no programming experience at
>k> all) why x and y remain unchanged above, but not z?

You shouldn't. That's not for beginners. Leave it waiing until you get
to the advanced level.

>k> Or consider this one:

>>>>> ham = [1, 2, 3, 4]
>>>>> spam = (ham,)
>>>>> spam
>k> ([1, 2, 3, 4],)
>>>>> spam[0] is ham
>k> True
>>>>> spam[0] += [5]
>k> Traceback (most recent call last):
>k>   File "<stdin>", line 1, in <module>
>k> TypeError: 'tuple' object does not support item assignment
>>>>> ham += [5]
>>>>> spam
>k> ([1, 2, 3, 4, 5, 5],)
>>>>> 

>k> What do you say to that?

Mutable and immutable. But use different examples. Like

ham = [1, 2, 3, 4]
spam = (1, 2, 3, 4)

spam[0] += 1 will give the same error message. You can't change the
components of a tuple.

Your example above is similar. The spam[0] += [5] appends the 5 to the
list in spam[0] (so it appends to ham), and then tries to assign the
result of it to spam[0], which is not allowed. That the item it tries to
assign is the same as the item that was already there doesn't matter.

So dont't forget += is a real assignment, even when it is an in-place
modification.  Your example just proves that. The language ref manual
says:

    With the exception of assigning to tuples and multiple targets in a
    single statement, the assignment done by augmented assignment
    statements is handled the same way as normal assignments.

But I think that your example isn't for beginners either.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From joshua at joshuakugler.com  Tue Jul  7 17:07:55 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Tue, 07 Jul 2009 13:07:55 -0800
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org> <h2up7a$epu$1@ger.gmane.org>
Message-ID: <h30dfc$ke2$1@ger.gmane.org>

Roger Binns wrote:
> Joshua Kugler wrote:
>> BTW, APSW is written by the same author as pysqlite.
> Not even remotely true :-)

Sorry about that...since pysqlite and APSW are both discusses on the
pysqlite list, I had made an incorrect assumption. Oops.

j



From no.email at please.post  Tue Jul  7 17:11:29 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 21:11:29 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com> <m2my7gb4g6.fsf@cs.uu.nl>
Message-ID: <h30dm1$g56$1@reader1.panix.com>

In <m2my7gb4g6.fsf at cs.uu.nl> Piet van Oostrum <piet at cs.uu.nl> writes:

>>>>>> kj <no.email at please.post> (k) wrote:

>>k> I'm having a hard time coming up with a reasonable way to explain
>>k> certain things to programming novices.

>>k> Consider the following interaction sequence:

>>>>>> def eggs(some_int, some_list, some_tuple):
>>k> ...     some_int += 2
>>k> ...     some_list += [2]
>>k> ...     some_tuple += (2,)
>>k> ...
>>>>>> x = 42
>>>>>> y = (42,) 
>>>>>> z = [42] 
>>>>>> eggs(x, y, z)
>>>>>> x
>>k> 42
>>>>>> y
>>k> (42,)
>>>>>> z
>>k> [42, 2] 
>>>>>> 

>>k> How do I explain to rank beginners (no programming experience at
>>k> all) why x and y remain unchanged above, but not z?

>You shouldn't. That's not for beginners.

No, of course not.  And I don't plan to present these examples to
them.  But beginners have a way of bumping into such conundrums
all on their own, and, as a former beginner myself, I can tell you
that they find them, at best, extremely frustrating, and at worst,
extremely discouraging.  I doubt that an answer of the form "don't
worry your pretty little head over this now; wait until your second
course" will do the trick.

Thanks for your comments!

kj


From no.email at please.post  Tue Jul  7 17:18:53 2009
From: no.email at please.post (kj)
Date: Tue, 7 Jul 2009 21:18:53 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
Message-ID: <h30e3t$g56$2@reader1.panix.com>

In <mailman.2796.1246997332.8015.python-list at python.org> Chris Rebert <clp2 at rebertia.com> writes:

>You might find the following helpful (partially):
>http://effbot.org/zone/call-by-object.htm


Extremely helpful.  Thanks!  (I learned more from it than someone
who will teach the stuff would care to admit...)

I had not realized how *profoundly* different the meaning of the
"=" in Python's

  spam = ham

is from the "=" in its

  spam[3] = ham[3]

So much for "explicit is better than implicit"...


And it confirmed Paul Graham's often-made assertion that all of
programming language design is still catching up to Lisp...

kj


From james at agentultra.com  Tue Jul  7 17:21:26 2009
From: james at agentultra.com (J Kenneth King)
Date: Tue, 07 Jul 2009 17:21:26 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
	<fc6b4e6a-5e89-4fed-914b-232fc6b1cf0e@h18g2000yqj.googlegroups.com>
Message-ID: <85hbxodwa1.fsf@agentultra.com>

Dr Mephesto <dnhkng at googlemail.com> writes:

> Sure, I am learning Objective C already, but the syntax is really
> unfriendly after python.
>
> I think it really depends on the type of app you want to write.
> Anything held back by network delays or that sits around waiting for
> user input are perfectly acceptable target apps. If you need speed for
> something really intensive, falling back to C is still much nicer than
> coding in Objective C. I agree that having a certain basic
> understanding of objective C is a must, but having the option to use a
> coder-friendly language like Ruby or Python can cut development time
> dramatically.
>
> If Ruby can do it (and it generally slower than python), why can
> Python also get a legal iPhone interpreter?

It can if you want to write the interpreter.

I just don't see the point.

I can understand wanting a higher level language than assembler or maybe
even C, but that's precisely what Objective-C is.

Unfortunately, while the hardware for these mobile platforms is getting
better these days, it's still not where it needs to be to run programs
written in interpreted languages, IMO.  Users typically only interact
with an app for around two minutes at a time.  Your app needs to be as
fast as it can be.  It's one of the few areas of software development
today where optimizations can be justified (the other are games and
scientific computing).

Trust me, if there were an SMS app for the iPhone that loaded faster
than the one that ships with it, guaranteed it would sell like hot-cakes
(if Apple would let it in the store of course).

If you do write the interpreter, let me know.  I would certainly
experiment with it.


From bearophileHUGS at lycos.com  Tue Jul  7 17:46:01 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 7 Jul 2009 14:46:01 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>

kj, as Piet van Oostrum as said, that's the difference between mutable
an immutable. It comes from the procedural nature of Python, and
probably an explanation of such topic can't be avoided if you want to
learn/teach Python.

Lot of people think that a language where everything is immutable is
simpler for newbies to understand (even if they have to learn what
higher-order functions are). That's why some people think Scheme or
other languages (even Clojure, I guess) are better for novices (Scheme
has mutability, but you can avoid showing it to newbies).

Some people say that languages that mostly encourage the use of
immutable data structures (like F#, Clojure, Scala and many other less
modern ones) help avoid bugs, maybe for novices too.

On the other hand, it's hard or impossible to actually remove
complexity from a system, and you usually just move it elsewhere. So
other things will become harder to do for those novices. I have no
idea if for the average novice it's simpler to learn to use a
immutables-based language instead of a mutables-based one (it can also
be possible that some novices prefer the first group, and other
novices prefer the second group).

>From what I have seen lot of students seem able to learn Python, so
it's not a bad choice.

Python isn't perfect, and in *many* situations it is pragmatic, for
example to increase its performance. Generally for a novice programmer
running speed is not important, but it's important to have a really
coherent and clean language. I've personally seen that for such people
even Python looks very "dirty" (even if it's one of the less dirty
ones).

For example a novice wants to see 124 / 38 to return the 62/19
fraction and not 3 or 3.263157894736842 :-)

People may be able to invent a clean and orthogonal language that's
easy to use and has very few compromises, fit for newbies. But this
language may be very slow, not much useful in practice (who knows?
Maybe there's a practical niche even for such very high level
language), and it doesn't teach how to use lower level languages like
C :-)

Today I think there are no languages really fit for teaching. Python
is one of the few fit ones, but it's getting more and more complex as
time passes because it's getting used in more and more complex real
world situations (a language fit for newbies must not have abstract
base classes, decorators, etc). D language is too much complex for a
newbie. Java is not too much bad, but it's requires to write too much
code, it's too much fussy (semicolons at the end of lines? Newbies say
that the computer is an idiot when it refuses code just because
there's a missing useless semicolon!), and it misses some necessary
things (first class functions! Damn). A nice language like Boo running
on the Mono VM seems another option :-)

In the past Pascal was good enough, but I think it's not good enough
anymore. The problem is that teaching is a niche activity (even if a
very important one). PLT Scheme is one of the few environments (beside
Squeak, Python itself, and little more) that look refined and
implemented well enough for such purpose.

See you later,
bearophile


From andrew.henshaw at gtri.gatech.edu  Tue Jul  7 17:48:37 2009
From: andrew.henshaw at gtri.gatech.edu (Andrew Henshaw)
Date: Tue, 7 Jul 2009 17:48:37 -0400
Subject: finding most common elements between thousands of multiple arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
Message-ID: <h30ft1$f0f$1@news-int.gatech.edu>


"mclovin" <hanooter at gmail.com> wrote in message 
news:c5332c9b-2348-4194-bfa0-d70c7710765d at x3g2000yqa.googlegroups.com...
> Currently I need to find the most common elements in thousands of
> arrays within one large array (arround 2 million instances with ~70k
> unique elements)
>
> so I set up a dictionary to handle the counting so when I am
> iterating  I up the count on the corrosponding dictionary element. I
> then iterate through the dictionary and find the 25 most common
> elements.
>
> the elements are initially held in a array within an array. so I am am
> just trying to find the most common elements between all the arrays
> contained in one large array.
> my current code looks something like this:
> d = {}
> for arr in my_array:
> -----for i in arr:
> #elements are numpy integers and thus are not accepted as dictionary
> keys
> -----------d[int(i)]=d.get(int(i),0)+1
>
> then I filter things down. but with my algorithm that only takes about
> 1 sec so I dont need to show it here since that isnt the problem.
>
>
> But there has to be something better. I have to do this many many
> times and it seems silly to iterate through 2 million things just to
> get 25. The element IDs are integers and are currently being held in
> numpy arrays in a larger array. this ID is what makes up the key to
> the dictionary.
>
> It currently takes about 5 seconds to accomplish this with my current
> algorithm.
>
> So does anyone know the best solution or algorithm? I think the trick
> lies in matrix intersections but I do not know.

Would the following work for you, or am I missing something?  For a 5Kx5K 
array, this takes about a tenth of a second on my machine.  This code 
doesn't deal with the sub-array issue.

#####################
import numpy
import time

LOWER = 0
UPPER = 1024
SIZE = 5000
NUM_BEST = 4

# sample data
data = numpy.random.randint(LOWER, UPPER, (SIZE,SIZE)).astype(int)

time.clock()
count = numpy.bincount(data.flat)
best = sorted(zip(count, range(len(count))))[-NUM_BEST:]
print 'time=', time.clock()
print best





From python at bdurham.com  Tue Jul  7 17:54:14 2009
From: python at bdurham.com (python at bdurham.com)
Date: Tue, 07 Jul 2009 17:54:14 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
In-Reply-To: <85hbxodwa1.fsf@agentultra.com>
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
	<fc6b4e6a-5e89-4fed-914b-232fc6b1cf0e@h18g2000yqj.googlegroups.com>
	<85hbxodwa1.fsf@agentultra.com>
Message-ID: <1247003654.9346.1323970563@webmail.messagingengine.com>

> If you do write the interpreter, let me know. I would certainly experiment with it.

+2 over here!

Malcolm


From nobody at nowhere.com  Tue Jul  7 18:37:43 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 07 Jul 2009 23:37:43 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
	<6xB4m.21104$vi5.8567@uutiset.elisa.fi>
Message-ID: <pan.2009.07.07.22.37.43.422000@nowhere.com>

On Tue, 07 Jul 2009 09:01:39 +0300, jack catcher (nick) wrote:

> Thanks for the comments. Unfortunately, such specifications aren't easy 
> to find, even in reviews. Fortunately several newer webcams seem at 
> least to use usb2.

Supporting USB-2 doesn't mean that the camera necessarily uses high-speed
(480Mbit/sec).

AFAIK, the only real difference between "USB-1 conformant" and "USB-2
conformant" is that the latter actually passed a test of its ability to
say "no, I can't do high-speed", while the former didn't. The check for
high-speed capability was designed such that it shouldn't cause problems
for USB-1 devices, but individual USB-1 devices weren't actually tested
for this.



From gagsl-py2 at yahoo.com.ar  Tue Jul  7 18:50:57 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 19:50:57 -0300
Subject: Python Error from Apress book
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
	<4A5345B1.8050306@ieee.org>
Message-ID: <op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
> Gabriel Genellina wrote:
>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com>  
>> escribi?:

>>> When I try to run the command as outlined in
>>> the book "simple_markup2.py < test_input.txt > test_output.html i get  
>>> the
>>> following error every time.
>>>
>>> IOError: [Errno 9] Bad file descriptor
>>
>> That's a Windows problem. When you execute the script as itself (either  
>> as you do in the command line, or by double-clicking on it), it doesn't  
>> have valid standard handles.
>> You have to invoke Python explicitely:
>>
>> python simple_markup2.py < test_input.txt > test_output.html
>>
>> (you may need to specify the full path to python.exe, or add the  
>> directory where Python is installed to your system PATH).
>>
> I use stdout this way all the time, with no problem (python 2.6, Windows  
> XP).  But as you point out, stdin redirection doesn't seem to work using  
> the file associations.  I do get a different error though. When I look  
> at sys.stdin, it shows an open file, with handle of zero, as expected.   
> But when I do a raw_input(), it gets:
>      EOFError: EOF when reading a line

I think the error depends on the specific OS version/service pack. But at  
least on XP this appears to fix it:

http://support.microsoft.com/kb/321788/en-us

-- 
Gabriel Genellina



From philr at aspexconsulting.co.nz  Tue Jul  7 19:04:25 2009
From: philr at aspexconsulting.co.nz (Phil Runciman)
Date: Wed, 8 Jul 2009 11:04:25 +1200
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2ujrs$4c0$1@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
Message-ID: <F232DBBD675E6E43A3BAC15A4F6767E6338256C967@FP-SBS2K8.aspex.co.nz.local>


-----Original Message-----
From: Dennis Lee Bieber [mailto:wlfraed at ix.netcom.com] 
Sent: Tuesday, 7 July 2009 4:45 p.m.
To: python-list at python.org
Subject: Re: A Bug By Any Other Name ...

On Mon, 6 Jul 2009 19:48:39 -0700, Daniel Fetchinson
<fetchinson at googlemail.com> declaimed the following in
gmane.comp.python.general:

> Yes, there are plenty of languages other than Java and C, but the
> influence of C is admittedly huge in Python. Why do you think loops
> are called "for", conditionals "if" or "while", functions return via
> "return", loops terminate via "break" and keep going via "continue"
> and why is comparison written as "==", etc, etc? All of these are
> coming from C (or an even earlier language) and my point is that users

	for, if, and return were common keywords in FORTRAN.

	Not to mention BASIC

	Both of which predate C

-- 
__________________________________________________________________________

Guido was probably influenced by the ALGOL language stream, which used "for" and "if". ALGOL 60 was a joint American and European effort and was significant in the late 50s and 60's.

Guido's fellow countryman, Edsgar Dijkstra, took this publication language (the ALGOL60 version) and produced a compiler for it. (It was not the first, but was very early on). Then B. Randell and L.J. Russell visited him, learnt from his experiences and returned to the UK to produce the KDF9 Whetstone ALGOL60 Compiler. Their book "ALGOL 60 Implementation" was a very early and influential book in the field and occupies a significant place in the history of computing. Computer language designers, including Nicholas Wirth (Pascal, Modula, Oberon), have been influenced by ALGOL.

Sadly, "C" and its ilk, come from a totally different stream of language development beginning with the likes of "CPL", "BCPL", "B" and developing into "C" and "C++". This stream was originally focussed on language portability and performance. This stream was much closer to the assembler language end of the language spectrum, whereas the other stream was heavily biased towards publication and later teaching. 

I could say more but will restrain myself.

My 2c 

Phil

FWIW "++" reeks of assembler language notation.

The KDF9 Whetstone ALGOL60 Compiler was the one I used at Whetstone for 1-Dimensional Transient Heat-Flow calculations and Steam-Table generation. Our course on it was 2.5 days long. We had wonderful training by English Electric, Kidsgrove staff. I hate to think how long the same course would be now, a month? 



From norseman at hughes.net  Tue Jul  7 19:07:04 2009
From: norseman at hughes.net (norseman)
Date: Tue, 07 Jul 2009 16:07:04 -0700
Subject: tough-to-explain Python
In-Reply-To: <a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
Message-ID: <4A53D518.6080306@hughes.net>

Bearophile wrote:
> kj, as Piet van Oostrum as said, that's the difference between mutable
> an immutable. It comes from the procedural nature of Python, and
> probably an explanation of such topic can't be avoided if you want to
> learn/teach Python.
...(snip)
> 
> See you later,
> bearophile

==========================Perhaps because it is the way I learned or the 
way I "naturally" approach programming, or maybe the way one influences 
the other, but at any rate I think "newbies" to programming should first 
learn a few basic concepts (if/then, for, while, do and other loops and 
other control constructs) and then be forced to deal with the computer 
on it's own terms. Assembly. Once the student learns what the computer 
already knows, that the whole thing is just bits and the combination of 
them determines it's responses, it then becomes easier to present 
'idealistic' concepts and their implementations.  With the knowledge and 
'mental picture' of the computer's nature the rest of the ideas for 
programming have a tendency to drift in the direction of reality and the 
underlying needs to fulfill the 'better' and/or 'easier' languages. 
Having both the knowledge of the 'full capabilities' of a computer and 
the experience of a formalized language the student can, or should, 
learn/compare the trade offs of each.  By understanding the computer (I 
at least) grasp the basics of a new language quite quickly. No, I don't 
become a guru overnight, if at all, but I do have the advantage in 
deciding if a given language is appropriate for a given job with very 
little research.

The more I delve into OOP the more I liken an 'object' to a box. A box 
with a shipping manifest.

There are big boxes,
little boxes,
squat boxes and so on.

A box can contain corn flakes,
bullets, raisins, rice, burlap, silk, motorcycle(s), soap and more.

The manifest describes contents.
The manifest is there but the description(s) change with content (type).
The descriptions always use one or more of the basics like: color, 
count, dimension and so forth.

Just like an OOP object.

A box can contain things of all sorts, including references to the 
contents of other box(es). A box can even be a virtual of another (the 
global concept).  The return statement, in this context, means hauling 
the contents of the box (and/or its manifest) back to (wherever) and 
disposing of the current box (a local).

Just like an OOP object.


It is easier to visualize a box and it's use than a non described blob.
Abstracts are never precise -  hence the evolution of the word.


The one thing a teacher will always fail is the same as anyone else who 
tries to adequately describe a pretty sunset to a person born totally 
blind. No point(s) of reference.



Time for me to sign off.  To all those that helped me when I needed it -

I thank you very much.

Food for thought: your watch (clock) does not tell time.
The watch (clock) only mimics one movement of the earth.
ie... 3 dimensions are still static, the 4th is movement.


Steve


From stef.mientki at gmail.com  Tue Jul  7 19:12:08 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Wed, 08 Jul 2009 01:12:08 +0200
Subject: Python/pyobjC Apps on iPhone now a possibility?
In-Reply-To: <85ljn0ej4h.fsf@agentultra.com>
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
Message-ID: <4A53D648.60005@gmail.com>


>> So, the question is, can the same thing be done for Python apps?
>>     
>
> I love Python and all, but it'd be apt to ask, what's the point?
>
> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
> device are already limited; running your program on top of an embedded
> Python interpreter would only be adding pressure to the constraints;
> even if it was an optimized interpreter.
>   
I don't know iPhone,
but I've done some experiments with 400 MHz arm, running Windows Mobile,
and found PocketPyGUI running very very well on these devices.

cheers,
Stef Mientki


From james at agentultra.com  Tue Jul  7 19:29:25 2009
From: james at agentultra.com (J Kenneth King)
Date: Tue, 07 Jul 2009 19:29:25 -0400
Subject: Python/pyobjC Apps on iPhone now a possibility?
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>
	<85ljn0ej4h.fsf@agentultra.com>
	<mailman.2804.1247008319.8015.python-list@python.org>
Message-ID: <85d48cdqcq.fsf@agentultra.com>

Stef Mientki <stef.mientki at gmail.com> writes:

>>> So, the question is, can the same thing be done for Python apps?
>>>     
>>
>> I love Python and all, but it'd be apt to ask, what's the point?
>>
>> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>> device are already limited; running your program on top of an embedded
>> Python interpreter would only be adding pressure to the constraints;
>> even if it was an optimized interpreter.
>>   
> I don't know iPhone,
> but I've done some experiments with 400 MHz arm, running Windows Mobile,
> and found PocketPyGUI running very very well on these devices.
>
> cheers,
> Stef Mientki

Sure, but it's pretty relative in the sense that it might be fast enough
if I'm sitting around but too slow if I want to enter some information
in the app before the next train comes.

As a programmer, I don't really see the benefit of using an embedded
interpreter on the iPhone.  Objective-C isn't the greatest language, but
it's easy to learn and well supported.  It also compiles into some
pretty speedy executables.

If you can sacrifice a little run-time speed for your users in exchange
for ease of development on your part, all the more to you.

My original point was that I don't see the benefit in that decision.




From gagsl-py2 at yahoo.com.ar  Tue Jul  7 19:44:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 20:44:45 -0300
Subject: Embedded Python : Why does thread lock here?
References: <00e8b4e8-5386-4f3d-b900-ab1ba41294f2@q40g2000prh.googlegroups.com>
Message-ID: <op.uwp1kvndx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 15:01:17 -0300, roschler <robert.oschler at gmail.com>  
escribi?:

> I have the Python Intepreter embedded in a Delphi (Object Pascal)
> program.  In the Python script shown below, I have a module that
> creates a thread object and starts it.

Do you *execute* the module or do you *import* it?
Isn't a good idea to spawn a thread by side effect of importing a module.

> The thread's run() call calls
> a function called deleteOutputVariables() declared at the module
> level.  In my code's first incarnation the thread's run() call would
> deadlock when trying to call the deleteOutputVariables() function
> declared at Module level.  I would never see the statement
> "(deleteOutputVariables) Top of Call" printed to the screen.  I now
> know that I must periodically call join() with a very fast time-out to
> keep Python threads happy, and that solved the problem.

What does the Delphi code? Isn't a join with a long timeout enough?

> However I am
> curious as to why it deadlocked at the deleteOutputVariables() call?
> Is it because deleteOutputVariables() is declared at the module level
> or because that function deletes module level variables?  If so why?

I don't know, but you can make some experiments - move te  
deleteOutputVariables as a method, or don't delete module level variables  
at all, and see what happens. I'd say both factors are irrelevant.

> # FUNCTION: Delete the variables given in the list.
> def deleteOutputVariables(theModule, theOutputVariablesListOfNames):
>     try:
>         print "(deleteOutputVariables) Top of call."
>         for theOutputVariableName in theOutputVariablesListOfNames:
>             if theModule.__dict__.has_key(theOutputVariableName):
>                 print "(Python::deleteOutputVariables) Deleting the
> Output Variable named " + theOutputVariableName
>                 del theModule.__dict__[theOutputVariableName]
>     except:
>         print "(deleteOutputVariables) Exception occurred."

As a rule, avoid using __special__ names. There is almost never need of  
using them (__init__ is a notable exception) unless you want to change  
Python behaviour.
In this case:

for theOutputVariableName in theOutputVariablesListOfNames:
   if hasattr(theModule, theOutputVariableName):
     delattr(theModule, theOutputVariableName)

(a name like theOutputVariablesListOfNames is too long for my taste, but  
that's a matter of style...)

> theNewThread = None
> theNewThread = threadRun("TestThread")

That first line is useless...

-- 
Gabriel Genellina



From stef.mientki at gmail.com  Tue Jul  7 19:46:51 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Wed, 08 Jul 2009 01:46:51 +0200
Subject: Python/pyobjC Apps on iPhone now a possibility?
In-Reply-To: <85d48cdqcq.fsf@agentultra.com>
References: <eb0ce77c-e40b-4505-b20e-93c85aa892c6@i6g2000yqj.googlegroups.com>	<85ljn0ej4h.fsf@agentultra.com>	<mailman.2804.1247008319.8015.python-list@python.org>
	<85d48cdqcq.fsf@agentultra.com>
Message-ID: <4A53DE6B.8040706@gmail.com>

J Kenneth King wrote:
> Stef Mientki <stef.mientki at gmail.com> writes:
>
>   
>>>> So, the question is, can the same thing be done for Python apps?
>>>>     
>>>>         
>>> I love Python and all, but it'd be apt to ask, what's the point?
>>>
>>> The iPhone is running on what? A 400Mhz ARM processor? Resources on the
>>> device are already limited; running your program on top of an embedded
>>> Python interpreter would only be adding pressure to the constraints;
>>> even if it was an optimized interpreter.
>>>   
>>>       
>> I don't know iPhone,
>> but I've done some experiments with 400 MHz arm, running Windows Mobile,
>> and found PocketPyGUI running very very well on these devices.
>>
>> cheers,
>> Stef Mientki
>>     
>
> Sure, but it's pretty relative in the sense that it might be fast enough
> if I'm sitting around but too slow if I want to enter some information
> in the app before the next train comes.
>
> As a programmer, I don't really see the benefit of using an embedded
> interpreter on the iPhone.  Objective-C isn't the greatest language, but
> it's easy to learn and well supported.  It also compiles into some
> pretty speedy executables.
>
> If you can sacrifice a little run-time speed for your users in exchange
> for ease of development on your part, all the more to you.
>
> My original point was that I don't see the benefit in that decision.
>
>
>   
ok 20 years ago I might have agreed with you,
but now a days,
speed of development is a much more important decision maker than speed 
of execution ;-)

cheers,
Stef


From freelancer317 at gmail.com  Tue Jul  7 19:49:54 2009
From: freelancer317 at gmail.com (Bret Fledderjohn)
Date: Tue, 7 Jul 2009 19:49:54 -0400
Subject: tough-to-explain Python
In-Reply-To: <4A53D518.6080306@hughes.net>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<4A53D518.6080306@hughes.net>
Message-ID: <b1d973a70907071649x126ee890wc7722f8d44449c24@mail.gmail.com>

I really enjoyed your boxes analogy, from a guy with a trucking background,
it makes a lot of sense!
-Bret


> ... The more I delve into OOP the more I liken an 'object' to a box. A box
> with a shipping manifest.
>
> There are big boxes,
> little boxes,
> squat boxes and so on.
>
> A box can contain corn flakes,
> bullets, raisins, rice, burlap, silk, motorcycle(s), soap and more.
>
> The manifest describes contents.
> The manifest is there but the description(s) change with content (type).
> The descriptions always use one or more of the basics like: color, count,
> dimension and so forth.
>
> Just like an OOP object.
>
> A box can contain things of all sorts, including references to the contents
> of other box(es). A box can even be a virtual of another (the global
> concept).  The return statement, in this context, means hauling the contents
> of the box (and/or its manifest) back to (wherever) and disposing of the
> current box (a local).
>
> Just like an OOP object.
>
>
> It is easier to visualize a box and it's use than a non described blob.
> Abstracts are never precise -  hence the evolution of the word.
>
>
> The one thing a teacher will always fail is the same as anyone else who
> tries to adequately describe a pretty sunset to a person born totally blind.
> No point(s) of reference.
>
>
>
> Time for me to sign off.  To all those that helped me when I needed it -
>
> I thank you very much.
>
> Food for thought: your watch (clock) does not tell time.
> The watch (clock) only mimics one movement of the earth.
> ie... 3 dimensions are still static, the 4th is movement.
>
>
> Steve


-- 
- Bret
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/83155beb/attachment-0001.html>

From ldo at geek-central.gen.new_zealand  Tue Jul  7 19:57:35 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Wed, 08 Jul 2009 11:57:35 +1200
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
Message-ID: <h30ndf$vho$1@lust.ihug.co.nz>

In message <mailman.2795.1246997268.8015.python-list at python.org>, Christian 
Heimes wrote:

> By the way most operating systems don't lock a file when it's opened for
> reading or writing or even executed.

The general conclusion seems to be that mandatory locking is more trouble 
than it's worth.



From ben+python at benfinney.id.au  Tue Jul  7 20:06:07 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Wed, 08 Jul 2009 10:06:07 +1000
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
	<h30e3t$g56$2@reader1.panix.com>
Message-ID: <8763e4ox74.fsf@benfinney.id.au>

kj <no.email at please.post> writes:

> In <mailman.2796.1246997332.8015.python-list at python.org> Chris Rebert <clp2 at rebertia.com> writes:
> 
> >You might find the following helpful (partially):
> >http://effbot.org/zone/call-by-object.htm
> 
> Extremely helpful.  Thanks!  (I learned more from it than someone
> who will teach the stuff would care to admit...)

I have got very good results from teaching using the analogy of ?paper
tags tied to physical objects? to describe Python's references to
values.

The analogy allows illustration of many otherwise confusing facts:

  * an assignment is the act of putting a tag onto an object

  * a tag leads to exactly one object, and it can be re-tied to a
    different object

  * an object can have arbitrarily many tags on it

  * containers (e.g. lists, dicts, sets, etc.) don't contain objects,
    they contain tags leading to objects

  * passing arguments to a function always makes new tags leading to the
    objects passed in, and throws those new tags away once the function
    returns

  * etc.

The analogy can then be contrasted to how Python *doesn't* do it: named
boxes with one value per box. You can point out that many other
languages do use this model, so they should be aware of it, but Python
doesn't use it.

> I had not realized how *profoundly* different the meaning of the
> "=" in Python's
> 
>   spam = ham

Access the object referenced by ?ham?, and assigns the reference ?spam?
to that object.

> is from the "=" in its
> 
>   spam[3] = ham[3]

Access the object referenced by ?ham[3]?, and assigns the reference
?spam[3]? to that object.

No, they're exactly the same. The only thing that's different is the
references you use; the assignment operates *exactly* the same in both
cases.

-- 
 \     ?We are no more free to believe whatever we want about God than |
  `\         we are free to adopt unjustified beliefs about science or |
_o__)              history [?].? ?Sam Harris, _The End of Faith_, 2004 |
Ben Finney


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 20:45:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 21:45:15 -0300
Subject: Write matrix to text file
References: <564970db0907071046o60e927dao21cc0557f1fa2903@mail.gmail.com>
Message-ID: <op.uwp4dpwvx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 14:46:47 -0300, Hanna Michelsen <hannarosie at gmail.com>  
escribi?:

> I'm working with both python and matlab at the moment and I was  
> wondering if
> there is an efficient way to take a 2-D array (of 1s and 0s) in python  
> and
> write it to a text file such that matlab will be able to create a sparse
> matrix from it later.

Your yesterday post appeared on this list successfully.
Posting the very same text again isn't going to help - those that are  
reading it now are likely the same that read it before.
If nobody replied, assume that something is wrong with the question  
itself. Not the grammar, looks clear to me. Maybe the meaning: you say "a  
2-D array" but you don't say what that means (a list? an array.array  
object? a Numpy array?).

Consider *who* might be able to answer: someone that knows both Python and  
matlab, and knows how to use a sparse matrix, and knows how to read data  
 from files, and knows how to generate such files from Python. The last  
part is the easy part, because people here is supposed to know how to do  
things in Python; but not how matlab works. So, please help people help  
you: tell us what file format would be fine for matlab to read, and people  
here surely will suggest the best way to write that in Python.

Reading http://www.mikeash.com/getting_answers.html may help too.

-- 
Gabriel Genellina



From gallium.arsenide at gmail.com  Tue Jul  7 20:55:13 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Tue, 7 Jul 2009 17:55:13 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com> <m2my7gb4g6.fsf@cs.uu.nl> 
	<h30dm1$g56$1@reader1.panix.com>
Message-ID: <8fa4563b-9de7-44cb-a8a2-a6d7c87a0ce4@q11g2000yqi.googlegroups.com>

On Jul 7, 5:11?pm, kj <no.em... at please.post> wrote:
> I don't plan to present these examples to them.
> But beginners have a way of bumping into such
> conundrums all on their own [...]. ?I doubt that
> an answer of the form "don't worry your pretty
> little head over this now; wait until your second
> course" will do the trick.

I agree that beginners are bound to come across difficult issues on
their own, and when they do, you have to at least try to explain,
rather than dismiss them.  I believe that the beginners which are most
curious, and thus most likely to run into things you didn't plan for
them, are also most likely to be ready and able to receive your
explanation.

That said, I think it's worth planning a fairly controlled flow of
information.  For example, you can go a LONG way without touching
tuples or the augmented assignment operators.

For your function example, I suppose the key ideas to understand are
binding and containers (which may or may not be mutable).  The
oversimplified version I think I would attempt to explain is that, as
far as the "outside world" is concerned, a function cannot rebind the
arguments passed to it.  However, the contents of a mutable container
may be altered without rebinding.  That is, you can hold a bucket,
pass that bucket to a function, and the function can put stuff in the
bucket or take stuff out without you ever letting go of the bucket.
When the function returns, you are still holding the bucket.

Nested containers, especially with "outside" bindings to inner
containers, may be tougher to visualize with real-world objects.
Hopefully by then the students can grasp a more abstract (pointerlike)
notion of binding!  Good luck!

John


From usernet at ilthio.net  Tue Jul  7 20:59:05 2009
From: usernet at ilthio.net (Tim Harig)
Date: Wed, 08 Jul 2009 00:59:05 GMT
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
Message-ID: <tbS4m.2451$Wj7.1467@nlpi065.nbdc.sbc.com>

On 2009-07-08, Fred Atkinson <fatkinson at mishmash.com> wrote:
> 	Is there a Python function I can use to get the user's IP
> address so I can display it on his browser?  

If you are using CGI you can get it from the REMOTE_ADDR environmental
variable.


From clp2 at rebertia.com  Tue Jul  7 21:09:09 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 7 Jul 2009 18:09:09 -0700
Subject: IP Address Function
In-Reply-To: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
Message-ID: <50697b2c0907071809y57b78162odd06b94cfff54d01@mail.gmail.com>

On Tue, Jul 7, 2009 at 6:45 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
> ? ? ? ?Is there a Python function I can use to get the user's IP
> address so I can display it on his browser?

from socket import gethostname, gethostbyname
ip = gethostbyname(gethostname())

Cheers,
Chris
-- 
http://blog.rebertia.com


From http  Tue Jul  7 21:24:28 2009
From: http (Paul Rubin)
Date: 07 Jul 2009 18:24:28 -0700
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
	<1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>
	<1f09e856-bd04-4d27-bf51-5d67953a7e13@y7g2000yqa.googlegroups.com>
Message-ID: <7xskh83r1v.fsf@ruckus.brouhaha.com>

pdpi <pdpinheiro at gmail.com> writes:
>     while abs(func(guess) - target) > epsilon:
>         guess = (lo + hi) / 2.
>         if sense * func(guess) > sense * target:
>             hi = guess
>         elif sense * func(guess) < sense * target:
>             lo = guess
>         elif lo == hi:
>             return None
>     return guess

That is completely confusing.  I get the, er, impression that "sense"
is supposed to change during the loop, and it takes much head
scratching to tell whether what you have there is right or not.  Also,
it calls func 3 times on each loop, which could be extremely slow.
You don't know what func does, so eliminating 2/3 of the calls to it
is not a micro-optimization--it could be a major time saving.

Yet another version:

    def _binary_search(x0, x1, func, target, epsilon):
        y0,y1 = func(x0), func(x1)
        while abs(y1 - target) > epsilon:
            if x0 == x1 or cmp(y0,target) == cmp(y1,target):
                return None
            xn = (x0 + x1) / 2.
            yn = func(xn)
            if cmp(yn,target) == cmp(y0,target):
               x0,y0 = xn,yn
            else:
               x1,y1 = xn,yn
        return x1


From gallium.arsenide at gmail.com  Tue Jul  7 21:26:13 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Tue, 7 Jul 2009 18:26:13 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org> 
	<h30e3t$g56$2@reader1.panix.com> <8763e4ox74.fsf@benfinney.id.au>
Message-ID: <197bfc81-05a6-4328-acec-3ddd5b733655@d32g2000yqh.googlegroups.com>

On Jul 7, 8:06?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> I have got very good results from teaching using
> the analogy of ?paper tags tied to physical objects?
> to describe Python's references to values.

Ah, I like that!  I think it's better than what I used in my post
(which I composed and submitted before yours showed up in my reader).

I am not formally a teacher, but I do try to help "nonprogrammers"
learn Python from time to time, and this will be a good one to
remember.

John


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 21:30:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 22:30:07 -0300
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2nqpf$d91$1@reader1.panix.com>
	<mailman.2688.1246883548.8015.python-list@python.org>
	<006e795f$0$9711$c3e8da3@news.astraweb.com>
	<h2uhcb$blq$1@panix3.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<4A5344BE.2080006@sequans.com>
Message-ID: <op.uwp6ght7x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 09:51:10 -0300, Jean-Michel Pichavant  
<jeanmichel at sequans.com> escribi?:
> I've never used sense in that way before, nor I've seen used by others  
> until now. However Kj is right, and my dictionary seems wrong  
> (wordreference.com). I've searched through others dictionaries and find  
> out this is actually applicable to functions. My bad.

Using a common word with its common meaning is important too in order to  
understand the code. It's hard enough for students to grasp the algorithm  
itself, why make it artificially harder by using strange variable names.

Some years ago I had to endure using an in-house framework with names like  
bring_XXX and fix_XXX instead of the usual names get_XXX and set_XXX (that  
was C++, emulating properties; I'm not sure of the actual verbs used,  
perhaps "obtain" and "establish", but certainly not get/set/put). Add some  
undecipherable comments in spanglish, profuse usage of macros that alter  
the lexical appearance of the language, and even reading code was a  
torture.

-- 
Gabriel Genellina



From fatkinson at mishmash.com  Tue Jul  7 21:45:24 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Tue, 07 Jul 2009 18:45:24 -0700
Subject: IP Address Function
Message-ID: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>

	Is there a Python function I can use to get the user's IP
address so I can display it on his browser?  

	Regards, 




							Fred 


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 21:54:03 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 07 Jul 2009 22:54:03 -0300
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
Message-ID: <op.uwp7kdr9x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 22:45:24 -0300, Fred Atkinson <fatkinson at mishmash.com>  
escribi?:

> 	Is there a Python function I can use to get the user's IP
> address so I can display it on his browser?

There is a long distance between "Python" and "browser" - you'll have to  
tell us what is in between the two.
By example, do you have a server and the user connects to it? is it  
running Python? how do you run the Python application?
And why do you want to do that on the server side? Isn't easier to do that  
on the client side? What about proxies? NAT?

If using CGI, look at the REMOTE_ADDR environment variable.

-- 
Gabriel Genellina



From steve at REMOVE-THIS-cybersource.com.au  Tue Jul  7 22:03:16 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 02:03:16 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
	<h30e3t$g56$2@reader1.panix.com>
Message-ID: <006fd94e$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 21:18:53 +0000, kj wrote:

> I had not realized how *profoundly* different the meaning of the "=" in
> Python's
> 
>   spam = ham
> 
> is from the "=" in its
> 
>   spam[3] = ham[3]
> 
> So much for "explicit is better than implicit"...

I'm sorry, I don't get it. Can you explain please? I don't see why it's 
so "profoundly" different. Apart from spam[3] = x not being permitted if 
spam is an immutable type.

I suppose though they are *fundamentally* different, in that spam=ham is 
dealt with by the compiler while spam[3]=ham is handled by the object 
spam using the __setitem__ method. Is that the difference you're talking 
about?


-- 
Steven


From python at bdurham.com  Tue Jul  7 22:40:05 2009
From: python at bdurham.com (python at bdurham.com)
Date: Tue, 07 Jul 2009 22:40:05 -0400
Subject: tough-to-explain Python
In-Reply-To: <197bfc81-05a6-4328-acec-3ddd5b733655@d32g2000yqh.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org>
	<h30e3t$g56$2@reader1.panix.com> <8763e4ox74.fsf@benfinney.id.au>
	<197bfc81-05a6-4328-acec-3ddd5b733655@d32g2000yqh.googlegroups.com>
Message-ID: <1247020805.1725.1324003095@webmail.messagingengine.com>

Ben,

> I have got very good results from teaching using the analogy of "paper tags tied to physical objects" to describe Python's references to values.

Great analogy!! And an excellent analogy for newcomers to Python. (this
would have saved me some personal pain in my early days).

Regards,
Malcolm


From gagsl-py2 at yahoo.com.ar  Tue Jul  7 23:02:53 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 08 Jul 2009 00:02:53 -0300
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <op.uwp22gpmx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 07 Jul 2009 17:04:46 -0300, kj <no.email at please.post> escribi?:

> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
>>>> ham = [1, 2, 3, 4]
>>>> spam = (ham,)
>>>> spam
> ([1, 2, 3, 4],)
>>>> spam[0] is ham
> True
>>>> spam[0] += [5]
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
>>>> ham += [5]
>>>> spam
> ([1, 2, 3, 4, 5, 5],)

>
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.

This article is based on an old thread in this list that is very
enlightening:

How To Think Like A Pythonista
http://python.net/crew/mwh/hacks/objectthink.html

and I'll quote just a paragraph from Alex Martelli:

?There is [...] a huge difference
between changing an object, and changing (mutating) some
OTHER object to which the first refers.

In Bologna over 100 years ago we had a statue of a local hero
depicted pointing forwards with his finger -- presumably to
the future, but given where exactly it was placed, the locals
soon identified it as "the statue that points to Hotel
Belfiore".  Then one day some enterprising developer bought
the hotel's building and restructured it -- in particular,
where the hotel used to be was now a restaurant, Da Carlo.

So, "the statue that points to Hotel Belfiore" had suddenly
become "the statue that points to Da Carlo"...!  Amazing
isn't it?  Considering that marble isn't very fluid and the
statue had not been moved or disturbed in any way...?

This is a real anecdote, by the way (except that I'm not
sure of the names of the hotel and restaurant involved --
I could be wrong on those), but I think it can still help
here.  The dictionary, or statue, has not changed at all,
even though the objects it refers/points to may have been
mutated beyond recognition, and the name people know it
by (the dictionary's string-representation) may therefore
change.  That name or representation was and is referring
to a non-intrinsic, non-persistent, "happenstance"
characteristic of the statue, or dictionary...?

-- 
Gabriel Genellina



From peter.milliken at gmail.com  Tue Jul  7 23:18:20 2009
From: peter.milliken at gmail.com (Peter)
Date: Tue, 7 Jul 2009 20:18:20 -0700 (PDT)
Subject: How to use Python to interface with Web pages?
Message-ID: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>

Any help would be appreciated :-)

I want to write an auction sniping tool in Python. I know Python, but
I know absolutely nothing about web pages, javascript etc i.e. I want
the program to automatically log me into my eBay account, access the
appropriate item, locate how many mins/seconds until the bid time ends
and then automatically place a bid at the last possible moment.

I can see the web-page source - it looks to be javascript (to my
untutored eye :-)).

But how do I enter data and "simulated" mouse presses on a web-page
that I have accessed via a Python program?

So where can I start to learn how to do this? Any books available? web
resources that show examples or offer tutorials?

I have (in the past) written some python to scoop data off web-sites
but I have never written anything that interactively interacts with
the web-page contents and don't know where to even start on this one.

Thanks for any help/pointers

Peter


From ralf at schoenian-online.de  Wed Jul  8 00:05:53 2009
From: ralf at schoenian-online.de (Ralf Schoenian)
Date: Wed, 08 Jul 2009 06:05:53 +0200
Subject: How to use Python to interface with Web pages?
In-Reply-To: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
References: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
Message-ID: <4A541B21.3030203@schoenian-online.de>

Peter wrote:
> Any help would be appreciated :-)
> 
> I want to write an auction sniping tool in Python. I know Python, but
> I know absolutely nothing about web pages, javascript etc i.e. I want
> the program to automatically log me into my eBay account, access the
> appropriate item, locate how many mins/seconds until the bid time ends
> and then automatically place a bid at the last possible moment.
> 
> I can see the web-page source - it looks to be javascript (to my
> untutored eye :-)).
> 
> But how do I enter data and "simulated" mouse presses on a web-page
> that I have accessed via a Python program?
> 
> So where can I start to learn how to do this? Any books available? web
> resources that show examples or offer tutorials?
> 
> I have (in the past) written some python to scoop data off web-sites
> but I have never written anything that interactively interacts with
> the web-page contents and don't know where to even start on this one.
> 
> Thanks for any help/pointers
> 
> Peter

Hi,

a good starting point possibly is 
http://wwwsearch.sourceforge.net/mechanize/

Regards,
Ralf


From sajmikins at gmail.com  Wed Jul  8 00:10:38 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 7 Jul 2009 21:10:38 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>

On Jul 7, 4:04 pm, kj <no.em... at please.post> wrote:
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
> Consider the following interaction sequence:
>
> >>> def eggs(some_int, some_list, some_tuple):
>
> ...     some_int += 2
> ...     some_list += [2]
> ...     some_tuple += (2,)
> ...
>
> >>> x = 42
> >>> y = (42,)
> >>> z = [42]
> >>> eggs(x, y, z)
> >>> x
> 42
> >>> y
> (42,)
> >>> z
> [42, 2]

You have transposed some_list and some some_tuple. I.e. you should be
calling eggs(x, z, y).

> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?

You don't. Rank beginners don't have enough background knowledge to
grok that code.

Why would you even tell the poor bastards about "+=" before they were
comfortable with (python's style of) function calls, immutable
integers, mutable lists and immutable tuples?

Let them use "x = x + y" until they have enough knowledge to
understand "augmented" assignment.

Syntax matters (I mean general order of things, not linguistic
syntax.)  Making an omelette requires putting eggs in a pan and
cracking them, but not in that order.

> Or consider this one:
>
> >>> ham = [1, 2, 3, 4]
> >>> spam = (ham,)
> >>> spam
> ([1, 2, 3, 4],)
> >>> spam[0] is ham
> True
> >>> spam[0] += [5]
>
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
> >>> ham += [5]
> >>> spam
>
> ([1, 2, 3, 4, 5, 5],)
>
>
>
> What do you say to that?

I say, "Don't use augmented assignment with indexed tuples."

Seriously, python's augmented assignment is almost magical. I think
you're just making trouble for yourself and your students if you
introduce it too early.

I get python pretty well (if I say so myself) but I wouldn't know how
to explain:

In [1]: def foo(a_list):
   ...:     a_list = a_list + [5]
   ...:
   ...:

In [2]: n = []

In [3]: foo(n)

In [4]: n
Out[4]: []

In [5]: def bar(a_list):
   ...:     a_list += [5]
   ...:
   ...:

In [6]: bar(n)

In [7]: n
Out[7]: [5]


It's "Just The Way It Is". Freakin' magic, man.

> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!

Frankly, I'm of the impression that it's a mistake not to start
teaching programming with /the bit/ and work your way up from there.
I'm not kidding. I wrote a (draft) article about this: "Computer
Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4

I really think the only good way to teach computers and programming is
to start with a bit, and build up from there. "Ontology recapitulates
phylogeny"

I realize that doesn't help you teach python, but I wanted to put it
out there.


From sjmachin at lexicon.net  Wed Jul  8 00:30:26 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 7 Jul 2009 21:30:26 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
Message-ID: <bb395e02-fe33-441e-8c01-27db196ef8e7@d9g2000prh.googlegroups.com>

On Jul 8, 3:05?am, dana <dana_at_w... at yahoo.com> wrote:
> I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
> modules together. Although I don't have Python 2.5, I've been informed
> the DBI module has been deprecated at 2.5.
>
> A few questions:
>
> 1) Although deprecated, will it work at all in 2.5? Does the fact that
> it is deprecrated mean it has been removed entirely, or does Python
> 2.5 simply issuing a warning?

Deprecated certainly doesn't mean removed.

>
> 2) What do I use in place of DBI for my Python 2.4. scripts that
> import modules DBI and ODBC together. I don't use DBI directly. It was
> simply a dependency for the ODBC module as best I knew.

For a start, none of (DBI, ODBC, dbi, odbc) are standard Python-
supplied modules. Perhaps you are referring to the odbc (and dbi) from
the pywin32 package? Where did you get them from? If you can't
remember, try this:

|Python 2.4.4 (#71, Oct 18 2006, 08:34:43) [MSC v.1310 32 bit (Intel)]
on win32
| Type "help", "copyright", "credits" or "license" for more
information.
| >>> import odbc
| >>> odbc.__file__
| 'C:\\python24\\lib\\site-packages\\win32\\odbc.pyd'
| >>>

If this is what you're talking about, you should be asking on the
pywin32 dicussion list (http://mail.python.org/mailman/listinfo/python-
win32).

General advice: if you are thinking of upgrading your Python version,
go straight to 2.6. odbc is AFAIK stuck at version 1.0 of the Python
DB API; consider switching to pyodbc (http://code.google.com/p/
pyodbc/)

HTH,
John


From rajat.dudeja at gmail.com  Wed Jul  8 00:31:12 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Tue, 7 Jul 2009 21:31:12 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
Message-ID: <e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>

On Jul 8, 4:57?am, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>
> Heimes wrote:
> > By the way most operating systems don't lock a file when it's opened for
> > reading or writing or even executed.
>
> The general conclusion seems to be that mandatory locking is more trouble
> than it's worth.

My OS is a windows XP sp3. All I'm trying to achieve is to close an
application ( which could be a notepad, a wordpad or some other text
editor) that have opened my file. Once the file is closed I can easily
delete that file.

I guess, if file is opened by one of that application, the file must
be locked and so is the reason I cannot delete the file.

Please suggest if this is fine.



From timr at probo.com  Wed Jul  8 01:11:12 2009
From: timr at probo.com (Tim Roberts)
Date: Tue, 07 Jul 2009 22:11:12 -0700
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
Message-ID: <0ca855t29jklb0o0gi31ourfk3lstdiepf@4ax.com>

Nobody <nobody at nowhere.com> wrote:
>
>The webcam is bound to do some encoding; most of them use USB "full speed"
>(12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.

That's not true.  Most of the web cams made in the last 5 years or so run
at high speed, 480 Mbps.  Full speed only gets you 1 fps at 640x480
uncompressed, so it's really only useful for the most primitive video
conference cams.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 02:09:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 06:09:19 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <007012f9$0$9711$c3e8da3@news.astraweb.com>

On Tue, 07 Jul 2009 20:04:46 +0000, kj wrote:

> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.

[...]


> Or consider this one:
> 
>>>> ham = [1, 2, 3, 4]
>>>> spam = (ham,)
>>>> spam
> ([1, 2, 3, 4],)
>>>> spam[0] is ham
> True
>>>> spam[0] += [5]
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment
>>>> ham += [5]
>>>> spam
> ([1, 2, 3, 4, 5, 5],)
>>>> 
>>>> 
> What do you say to that?


That one surely is very straight forward. Just like the exception says, 
tuples don't support item assignment, so spam[0] += [5] is not allowed.

But just because you have put a list inside a tuple doesn't mean the list 
stops being a list -- you can still append to the list, which is what 
ham += [5] does. So spam is unchanged: it is still the one-item tuple 
containing a list. It is just that the list has now been modified.

This is only troublesome (in my opinion) if you imagine that tuples are 
somehow magical "frozen-lists", where the contents can't be modified once 
created. That's not the case -- the tuple itself can't be modified, but 
the objects inside it remain ordinary objects, and the mutable ones can 
be modified.

The thing to remember is that the tuple spam doesn't know anything about 
the *name* ham -- it knows the object referred to by the name ham. You 
can modify the name, and nothing happens to the tuple:

>>> spam
([1, 2, 3, 4, 5],)
>>> ham = [5]
>>> spam
([1, 2, 3, 4, 5],)

Or if you prefer:

>>> ham = spam[0]  # label the list inside spam as 'ham'
>>> ham += [6]  # modify the list labelled as 'ham'
>>> spam
([1, 2, 3, 4, 5, 6],)
>>> pork = ham  # create a new label, 'pork', and bind it to the same list
>>> del ham  # throw away the label 'ham'
>>> pork += [7]  # modify the list labelled as 'pork'
>>> spam
([1, 2, 3, 4, 5, 6, 7],)


It's all about the objects, not the names.



-- 
Steven


From dhananjay.c.joshi at gmail.com  Wed Jul  8 02:10:59 2009
From: dhananjay.c.joshi at gmail.com (Dhananjay)
Date: Wed, 8 Jul 2009 11:40:59 +0530
Subject: count
Message-ID: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>

Dear all,

I have file as follows,however, tab seperated (not shown in following file):

     6       3       4.309726
     7       65     93.377388
     8       47     50.111952
     9       270   253.045923
     10     184    182.684670
     11     76     121.853455
     12     85     136.283470
     13     114    145.910662
     14     45      80.703013
     15     44      47.154646
     16     41      66.461339
     17     16      33.819488
     18     127     136.105455
     19     70      88.798681
     20     29      61.297823


I wanted to sort column 2 in assending order  and I read whole file in array
"data" and did the following:

data.sort(key = lambda fields:(fields[2]))

I have sorted column 2, however I want to count the numbers in the column 2.
i.e. I want to know, for example, how many repeates of say '3' (first row,
2nd column in above data) are there in column 2.

I could write seperate programme to get the result.s.

However, is there any way to count the numbers there itself while sorting in
column 2 ?


Thanking you in advance,


-- Dhananjay
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/507f91f3/attachment-0001.html>

From romeoamp at gmail.com  Wed Jul  8 02:13:42 2009
From: romeoamp at gmail.com (romeoamp)
Date: Tue, 7 Jul 2009 23:13:42 -0700 (PDT)
Subject: SSH utility
In-Reply-To: <a47bf8f1-7889-4ad2-bc49-f04c8487e3e2@r15g2000prh.googlegroups.com>
References: <b41c8ad7-e286-4147-893c-c7b2adffe73a@b30g2000prf.googlegroups.com>
	<a47bf8f1-7889-4ad2-bc49-f04c8487e3e2@r15g2000prh.googlegroups.com>
Message-ID: <24385961.post@talk.nabble.com>


Please look at on :


http://www.lag.net/paramiko/ http://www.lag.net/paramiko/ 


Sample Code: Find Attachment


Thanks,
S.V.RAJKUMAR,
XOU Solutions India Private Limited
No. 37, PM Towers,
Greams Road,
Thousand Lights,
Chennai - 6 .
Mobile No : +91 - 9940632275. 





half.italian wrote:
> 
> On Aug 11, 5:17?am, Edwin.Mad... at VerizonWireless.com wrote:
>> for similar tasks, I use pexpecthttp://pypi.python.org/pypi/pexpect.
>>
>> spawning bash process and simulate an interactive session. Here sending
>> ls command, retrieving results and exiting. In the spawned process ssh or
>> any other command, is just another command.
>>
>> ------------actual session--------------------------
>> $ python
>> Python 2.5.1 (r251:54863, May 18 2007, 16:56:43)
>> [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
>> Type "help", "copyright", "credits" or "license" for more information.>>>
>> import pexpect
>> >>> c = pexpect.spawn('/bin/bash')
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('\x1b[?1034hmadared at NJWARHQD0IT696A:~\r\n', '$ ')>>> c.sendline('ls')
>> 3
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('ls\r\x.txt ?xx.txt ?xy.txt ?y.txt\r\nmadared at NJWARHQD0IT696A:~\r\n', '$
>> ')>>> c.sendline('exit')
>> 5
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 1
>> >>> c.before, c.after
>>
>> ('exit\r\nexit\r\n', )>>> exit()
>>
>> madared at NJWARHQD0IT696A:~
>> $
>> ---------------------------------------------------------------
>>
>> hope that helps.
>>
>> regards.
>> Edwin
>>
>> -----Original Message-----
>> From: python-list-bounces+edwin.madari=verizonwireless.... at python.org
>>
>> [mailto:python-list-bounces+edwin.madari=verizonwireless.... at python.org]
>> On Behalf Of James Brady
>> Sent: Monday, August 11, 2008 12:26 AM
>> To: python-l... at python.org
>> Subject: SSH utility
>>
>> Hi all,
>> I'm looking for a python library that lets me execute shell commands
>> on remote machines.
>>
>> I've tried a few SSH utilities so far: paramiko, PySSH and pssh;
>> unfortunately all been unreliable, and repeated questions on their
>> respective mailing lists haven't been answered...
>>
>> It seems like the sort of commodity task that there should be a pretty
>> robust library for. Are there any suggestions for alternative
>> libraries or approaches?
>>
>> Thanks!
>> James
>> --http://mail.python.org/mailman/listinfo/python-list
>>
>> The information contained in this message and any attachment may be
>> proprietary, confidential, and privileged or subject to the work
>> product doctrine and thus protected from disclosure. ?If the reader
>> of this message is not the intended recipient, or an employee or
>> agent responsible for delivering this message to the intended
>> recipient, you are hereby notified that any dissemination,
>> distribution or copying of this communication is strictly prohibited.
>> If you have received this communication in error, please notify me
>> immediately by replying to this message and deleting it and all
>> copies and backups thereof. ?Thank you.
> 
> I second pexpect and the nice little module that comes with it
> ssh_session.py.
> 
> Been using it for ages now!
> 
> ~Sean
> --
> http://mail.python.org/mailman/listinfo/python-list
> 
> 
http://www.nabble.com/file/p24385961/sshclient.py sshclient.py 
-- 
View this message in context: http://www.nabble.com/SSH-utility-tp18920030p24385961.html
Sent from the Python - python-list mailing list archive at Nabble.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090707/c8b70a94/attachment-0001.html>

From romeoamp at gmail.com  Wed Jul  8 02:15:08 2009
From: romeoamp at gmail.com (romeoamp)
Date: Tue, 7 Jul 2009 23:15:08 -0700 (PDT)
Subject: SSH utility
Message-ID: <24385961.post@talk.nabble.com>


Please look at on :


http://www.lag.net/paramiko/

Sample Code: Find Attachment


Thanks,
S.V.RAJKUMAR,
XOU Solutions India Private Limited
No. 37, PM Towers,
Greams Road,
Thousand Lights,
Chennai - 6 .
Mobile No : +91 - 9940632275. 



half.italian wrote:
> 
> On Aug 11, 5:17?am, Edwin.Mad... at VerizonWireless.com wrote:
>> for similar tasks, I use pexpecthttp://pypi.python.org/pypi/pexpect.
>>
>> spawning bash process and simulate an interactive session. Here sending
>> ls command, retrieving results and exiting. In the spawned process ssh or
>> any other command, is just another command.
>>
>> ------------actual session--------------------------
>> $ python
>> Python 2.5.1 (r251:54863, May 18 2007, 16:56:43)
>> [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
>> Type "help", "copyright", "credits" or "license" for more information.>>>
>> import pexpect
>> >>> c = pexpect.spawn('/bin/bash')
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('\x1b[?1034hmadared at NJWARHQD0IT696A:~\r\n', '$ ')>>> c.sendline('ls')
>> 3
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 2
>> >>> c.before, c.after
>>
>> ('ls\r\x.txt ?xx.txt ?xy.txt ?y.txt\r\nmadared at NJWARHQD0IT696A:~\r\n', '$
>> ')>>> c.sendline('exit')
>> 5
>> >>> c.expect([pexpect.TIMEOUT, pexpect.EOF, '\$ '])
>> 1
>> >>> c.before, c.after
>>
>> ('exit\r\nexit\r\n', <class 'pexpect.EOF'>)>>> exit()
>>
>> madared at NJWARHQD0IT696A:~
>> $
>> ---------------------------------------------------------------
>>
>> hope that helps.
>>
>> regards.
>> Edwin
>>
>> -----Original Message-----
>> From: python-list-bounces+edwin.madari=verizonwireless.... at python.org
>>
>> [mailto:python-list-bounces+edwin.madari=verizonwireless.... at python.org]
>> On Behalf Of James Brady
>> Sent: Monday, August 11, 2008 12:26 AM
>> To: python-l... at python.org
>> Subject: SSH utility
>>
>> Hi all,
>> I'm looking for a python library that lets me execute shell commands
>> on remote machines.
>>
>> I've tried a few SSH utilities so far: paramiko, PySSH and pssh;
>> unfortunately all been unreliable, and repeated questions on their
>> respective mailing lists haven't been answered...
>>
>> It seems like the sort of commodity task that there should be a pretty
>> robust library for. Are there any suggestions for alternative
>> libraries or approaches?
>>
>> Thanks!
>> James
>> --http://mail.python.org/mailman/listinfo/python-list
>>
>> The information contained in this message and any attachment may be
>> proprietary, confidential, and privileged or subject to the work
>> product doctrine and thus protected from disclosure. ?If the reader
>> of this message is not the intended recipient, or an employee or
>> agent responsible for delivering this message to the intended
>> recipient, you are hereby notified that any dissemination,
>> distribution or copying of this communication is strictly prohibited.
>> If you have received this communication in error, please notify me
>> immediately by replying to this message and deleting it and all
>> copies and backups thereof. ?Thank you.
> 
> I second pexpect and the nice little module that comes with it
> ssh_session.py.
> 
> Been using it for ages now!
> 
> ~Sean
> --
> http://mail.python.org/mailman/listinfo/python-list
> 
> 
http://www.nabble.com/file/p24385961/sshclient.py sshclient.py 
-- 
View this message in context: http://www.nabble.com/SSH-utility-tp18920030p24385961.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From python at rcn.com  Wed Jul  8 03:11:50 2009
From: python at rcn.com (Raymond Hettinger)
Date: Wed, 8 Jul 2009 00:11:50 -0700 (PDT)
Subject: finding most common elements between thousands of multiple 
	arrays.
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com> 
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
Message-ID: <0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>

[Scott David Daniels]
> def most_frequent(arr, N):
> ? ? ?'''Return the top N (freq, val) elements in arr'''
> ? ? ?counted = frequency(arr) # get an iterator for freq-val pairs
> ? ? ?heap = []
> ? ? ?# First, just fill up the array with the first N distinct
> ? ? ?for i in range(N):
> ? ? ? ? ?try:
> ? ? ? ? ? ? ?heap.append(counted.next())
> ? ? ? ? ?except StopIteration:
> ? ? ? ? ? ? ?break # If we run out here, no need for a heap
> ? ? ?else:
> ? ? ? ? ?# more to go, switch to a min-heap, and replace the least
> ? ? ? ? ?# element every time we find something better
> ? ? ? ? ?heapq.heapify(heap)
> ? ? ? ? ?for pair in counted:
> ? ? ? ? ? ? ?if pair > heap[0]:
> ? ? ? ? ? ? ? ? ?heapq.heapreplace(heap, pair)
> ? ? ?return sorted(heap, reverse=True) # put most frequent first.

In Py2.4 and later, see heapq.nlargest().
In Py3.1, see collections.Counter(data).most_common(n)


Raymond


From wuwei23 at gmail.com  Wed Jul  8 03:29:32 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 8 Jul 2009 00:29:32 -0700 (PDT)
Subject: How to use Python to interface with Web pages?
References: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
Message-ID: <127e0a78-89fc-4c09-bda7-95836c57ac58@v37g2000prg.googlegroups.com>

On Jul 8, 1:18?pm, Peter <peter.milli... at gmail.com> wrote:
> I can see the web-page source - it looks to be javascript (to my
> untutored eye :-)).
>
> But how do I enter data and "simulated" mouse presses on a web-page
> that I have accessed via a Python program?
> [...]
> I have (in the past) written some python to scoop data off web-sites
> but I have never written anything that interactively interacts with
> the web-page contents and don't know where to even start on this one.

I don't have much experience with it, but for interacting with
javascript-heavy pages you might want to take a look at Selenium:

http://seleniumhq.org/
http://pypi.python.org/pypi/selenium
http://jimmyg.org/blog/2009/getting-started-with-selenium-and-python.html
http://joker.linuxstuff.pl/documentation/make_selenium

It's primarily aimed at testing web app UIs, but if it allows for
values to be passed into tests then 'test' == 'action' in terms of
your requirements.

Hope this helps.

- alex23


From bieffe62 at gmail.com  Wed Jul  8 03:32:07 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Wed, 8 Jul 2009 00:32:07 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <70654e24-aa1b-4a78-87a3-d36873da6109@i6g2000yqj.googlegroups.com>

On Jul 7, 10:04?pm, kj <no.em... at please.post> wrote:
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>
> Consider the following interaction sequence:
>
> >>> def eggs(some_int, some_list, some_tuple):
>
> ... ? ? some_int += 2
> ... ? ? some_list += [2]
> ... ? ? some_tuple += (2,)
> ...
>
> >>> x = 42
> >>> y = (42,)
> >>> z = [42]
> >>> eggs(x, y, z)
> >>> x
> 42
> >>> y
> (42,)
> >>> z
> [42, 2]
>
> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?
>
> Or consider this one:
>
> >>> ham = [1, 2, 3, 4]
> >>> spam = (ham,)
> >>> spam
> ([1, 2, 3, 4],)
> >>> spam[0] is ham
> True
> >>> spam[0] += [5]
>
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> TypeError: 'tuple' object does not support item assignment>>> ham += [5]
> >>> spam
>
> ([1, 2, 3, 4, 5, 5],)
>
>
>
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!
>
> TIA!
>
> kj

I would go with something like this:

"""
In object oriented programming, the same function or operator can be
used to represent
different things. This is called overloading. To understand what the
operator/function do, we have to look at
the kind of object it is applied to.
In this case, the operator "+=" means two different things:
- for strings and numbers it means : "create a new object by merging
the two operands". This is why the original object is left the same.
- for lists, it means : "increase the left operand with the contents
of the right operand". This is why the original object is changed
"""

You couuld also add:
"""
You see, in python everithing is an object. Some object can be changed
(mutable objects), others cannot.
"""
but this is another story.


P:S : Sometime I think they should not have allowed += on immutables
and forced everybody to write s = s + "some more".

Ciao
----
FB


From mail at timgolden.me.uk  Wed Jul  8 03:45:58 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 08 Jul 2009 08:45:58 +0100
Subject: Check file is locked?
In-Reply-To: <e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
Message-ID: <4A544EB6.5090404@timgolden.me.uk>

Rajat wrote:
> On Jul 8, 4:57 am, Lawrence D'Oliveiro <l... at geek-
> central.gen.new_zealand> wrote:
>> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>>
>> Heimes wrote:
>>> By the way most operating systems don't lock a file when it's opened for
>>> reading or writing or even executed.
>> The general conclusion seems to be that mandatory locking is more trouble
>> than it's worth.
> 
> My OS is a windows XP sp3. All I'm trying to achieve is to close an
> application ( which could be a notepad, a wordpad or some other text
> editor) that have opened my file. Once the file is closed I can easily
> delete that file.
> 
> I guess, if file is opened by one of that application, the file must
> be locked and so is the reason I cannot delete the file.


I assume that your real requirement is: I can't open/close/delete
this file; it must be locked by something else; what is that
something else?

The simplest thing is probably to run sysinternals' handle util:

  http://technet.microsoft.com/en-us/sysinternals/bb896655.aspx

and use the subprocess module to parse the output.
That will give you the pid, and you can then use, eg, psutil:

  http://code.google.com/p/psutil/

to get the details of the process.

TJG


From piet at cs.uu.nl  Wed Jul  8 04:11:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 10:11:35 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
Message-ID: <m2hbxnbnm0.fsf@cs.uu.nl>

>>>>> Simon Forman <sajmikins at gmail.com> (SF) wrote:

>SF> Why would you even tell the poor bastards about "+=" before they were
>SF> comfortable with (python's style of) function calls, immutable
>SF> integers, mutable lists and immutable tuples?

>SF> Let them use "x = x + y" until they have enough knowledge to
>SF> understand "augmented" assignment.

And *then* you can tell them that "x += y" can be subtly different from 
"x = x + y", which is what happened in the example that the OP gave.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From gagsl-py2 at yahoo.com.ar  Wed Jul  8 04:13:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 08 Jul 2009 05:13:42 -0300
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<70654e24-aa1b-4a78-87a3-d36873da6109@i6g2000yqj.googlegroups.com>
Message-ID: <op.uwqo44t2x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 04:32:07 -0300, Francesco Bochicchio  
<bieffe62 at gmail.com> escribi?:

> I would go with something like this:
>
> """
> In object oriented programming, the same function or operator can be
> used to represent
> different things. This is called overloading. To understand what the
> operator/function do, we have to look at
> the kind of object it is applied to.
> In this case, the operator "+=" means two different things:
> - for strings and numbers it means : "create a new object by merging
> the two operands". This is why the original object is left the same.
> - for lists, it means : "increase the left operand with the contents
> of the right operand". This is why the original object is changed
> """

Mmm, but this isn't quite exact. += isn't an operator, but a statement  
(augmented assignment). a += b translates to: [*]

a = a.__iadd__(b) [*]

It's up to the __iadd__ implementation to return the same object or a new  
one, and the assignment occurs even if the same object is returned.

If you think of an assignments as binding names to objects (well, that's  
the documented behavior, btw) things become more clear.

> P:S : Sometime I think they should not have allowed += on immutables
> and forced everybody to write s = s + "some more".

I think not everyone agreed when += was introduced.
But now, having s += "some more" allows the operation to be optimized.

[*] except 'a' is evaluated only once

-- 
Gabriel Genellina



From helvinlui at gmail.com  Wed Jul  8 04:51:07 2009
From: helvinlui at gmail.com (Helvin)
Date: Wed, 8 Jul 2009 01:51:07 -0700 (PDT)
Subject: PyQt GUI
Message-ID: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>

Hi experts!

I'm developing a GUI for a software using PyQT, and need 3D
visualization. Should I use PyOpenGL or VTK?
I understand that the PyQt package comes with a opengl module. What
else would I need? I think I need to download opengl. but how? where?
I have VTK and pyVTK installed, but I don't know how to use it in my
code, as when I run it, an error says it can't find the vtk module.

Help would be sooooo appreciated!
Helvin


From fatkinson at mishmash.com  Wed Jul  8 04:55:29 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Wed, 08 Jul 2009 01:55:29 -0700
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
Message-ID: <jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>

On Tue, 07 Jul 2009 22:54:03 -0300, "Gabriel Genellina"
<gagsl-py2 at yahoo.com.ar> wrote:

>En Tue, 07 Jul 2009 22:45:24 -0300, Fred Atkinson <fatkinson at mishmash.com>  
>escribi?:
>
>> 	Is there a Python function I can use to get the user's IP
>> address so I can display it on his browser?
>
>There is a long distance between "Python" and "browser" - you'll have to  
>tell us what is in between the two.

	I want to have a Web page come up (written in Python, cgi)
that returns the IP address of the browser (user's PC's IP address).  

>By example, do you have a server and the user connects to it? is it  
>running Python? how do you run the Python application?
>And why do you want to do that on the server side? Isn't easier to do that  
>on the client side? What about proxies? NAT?

	Yes.  By CGI.  

>If using CGI, look at the REMOTE_ADDR environment variable.

	I did look at REMOTE_ADDR but I've been unable to figure out
the correct way to code it.  I've tried a number of ways but I've been
unsuccessful.  

	Ideally, I'd like to store the brower's IP address in a string
and then print the string on the Web page from a Python CGI script.  

	Regards, 



						Fred 


From vilya.harvey at gmail.com  Wed Jul  8 04:56:55 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Wed, 8 Jul 2009 09:56:55 +0100
Subject: count
In-Reply-To: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
Message-ID: <6aef848f0907080156k114b0bb0me13b26904683d411@mail.gmail.com>

2009/7/8 Dhananjay <dhananjay.c.joshi at gmail.com>:
> I wanted to sort column 2 in assending order? and I read whole file in array
> "data" and did the following:
>
> data.sort(key = lambda fields:(fields[2]))
>
> I have sorted column 2, however I want to count the numbers in the column 2.
> i.e. I want to know, for example, how many repeates of say '3' (first row,
> 2nd column in above data) are there in column 2.

One thing: indexes in Python start from 0, so the second column has an
index of 1 not 2. In other words, it should be data.sort(key = lambda
fields: fields[1]) instead.

With that out of the way, the following will print out a count of each
unique item in the second column:

from itertools import groupby
for x, g in groupby([fields[1] for fields in data]):
    print x, len(tuple(g))

Hope that helps,
Vil.


From deets at nospam.web.de  Wed Jul  8 05:11:51 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 08 Jul 2009 11:11:51 +0200
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
Message-ID: <7bj5ulF22b4ktU1@mid.uni-berlin.de>

Helvin wrote:

> Hi experts!
> 
> I'm developing a GUI for a software using PyQT, and need 3D
> visualization. Should I use PyOpenGL or VTK?
> I understand that the PyQt package comes with a opengl module. What
> else would I need? I think I need to download opengl. but how? where?
> I have VTK and pyVTK installed, but I don't know how to use it in my
> code, as when I run it, an error says it can't find the vtk module.

VTK won't mix with Qt. And I don't think you need to download opengl - it
either comes with your system (or gfx-drivers), or not. I'm not sure if Qt
actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
PyOpenGL I guess.

Diez


From phil at riverbankcomputing.com  Wed Jul  8 05:23:10 2009
From: phil at riverbankcomputing.com (Phil Thompson)
Date: Wed, 08 Jul 2009 10:23:10 +0100
Subject: PyQt GUI
In-Reply-To: <7bj5ulF22b4ktU1@mid.uni-berlin.de>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
Message-ID: <66fe05cfa1805aef3a0d4aadc4e7c9c1@localhost>

On Wed, 08 Jul 2009 11:11:51 +0200, "Diez B. Roggisch"
<deets at nospam.web.de>
wrote:
> Helvin wrote:
> 
>> Hi experts!
>> 
>> I'm developing a GUI for a software using PyQT, and need 3D
>> visualization. Should I use PyOpenGL or VTK?
>> I understand that the PyQt package comes with a opengl module. What
>> else would I need? I think I need to download opengl. but how? where?
>> I have VTK and pyVTK installed, but I don't know how to use it in my
>> code, as when I run it, an error says it can't find the vtk module.
> 
> VTK won't mix with Qt. And I don't think you need to download opengl - it
> either comes with your system (or gfx-drivers), or not. I'm not sure if
Qt
> actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
> PyOpenGL I guess.

VTK has explicit support for both Qt (ie. via C++) and PyQt.

Phil


From eckhardt at satorlaser.com  Wed Jul  8 05:24:28 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Wed, 08 Jul 2009 11:24:28 +0200
Subject: Fractions as result from divisions (was: Re: tough-to-explain Python)
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
Message-ID: <c75ei6-e0i.ln1@satorlaser.homedns.org>

Bearophile wrote:
> For example a novice wants to see 124 / 38 to return the 62/19
> fraction and not 3 or 3.263157894736842 :-)

Python has adopted the latter of the three for operator / and the the second
one for operator //. I wonder if it was considered to just return a
fraction from that operation.

 x = 3/5
 -> x = fraction(3, 5)
 x = x*7
 -> x = fraction(21, 5)
 x = x/2
 -> x = fraction(21, 10)
 range(x)
 -> error, x not an integer
 range(int(x))
 -> [0, 1,]
 y = float(x)
 -> y = 2.1

This would have allowed keeping the operator what people are used to. On the
other hand, implicit conversion to either of float or int would have been
avoided, which is usually the #1 cause for subtle problems.


Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From davea at ieee.org  Wed Jul  8 05:35:54 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 08 Jul 2009 05:35:54 -0400
Subject: Python Error from Apress book
In-Reply-To: <op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
References: <24364269.post@talk.nabble.com>	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>	<4A5345B1.8050306@ieee.org>
	<op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A54687A.6010004@ieee.org>



Gabriel Genellina wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">En Tue, 
> 07 Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
>> Gabriel Genellina wrote:
>>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com> 
>>> escribi?:
>
>>>> When I try to run the command as outlined in
>>>> the book "simple_markup2.py < test_input.txt > test_output.html i 
>>>> get the
>>>> following error every time.
>>>>
>>>> IOError: [Errno 9] Bad file descriptor
>>>
>>> That's a Windows problem. When you execute the script as itself 
>>> (either as you do in the command line, or by double-clicking on it), 
>>> it doesn't have valid standard handles.
>>> You have to invoke Python explicitely:
>>>
>>> python simple_markup2.py < test_input.txt > test_output.html
>>>
>>> (you may need to specify the full path to python.exe, or add the 
>>> directory where Python is installed to your system PATH).
>>>
>> I use stdout this way all the time, with no problem (python 2.6, 
>> Windows XP).  But as you point out, stdin redirection doesn't seem to 
>> work using the file associations.  I do get a different error though. 
>> When I look at sys.stdin, it shows an open file, with handle of zero, 
>> as expected.  But when I do a raw_input(), it gets:
>>      EOFError: EOF when reading a line
>
> I think the error depends on the specific OS version/service pack. But 
> at least on XP this appears to fix it:
>
> http://support.microsoft.com/kb/321788/en-us
>
Thanks for the link.  Looking at that one, it indicates that Windows 
2000 fixed it in SP4, and XP fixed it in Sp1.  But I'm already running 
XP SP3, so I wonder if it's something new.

Matt, what OS version are you running, and exactly what is happening 
when the error occurs?  (you should be able to figure that out from the 
stack trace)


DaveA


From deets at nospam.web.de  Wed Jul  8 05:44:15 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 08 Jul 2009 11:44:15 +0200
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org>
Message-ID: <7bj7reF23oparU1@mid.uni-berlin.de>

Phil Thompson wrote:

> On Wed, 08 Jul 2009 11:11:51 +0200, "Diez B. Roggisch"
> <deets at nospam.web.de>
> wrote:
>> Helvin wrote:
>> 
>>> Hi experts!
>>> 
>>> I'm developing a GUI for a software using PyQT, and need 3D
>>> visualization. Should I use PyOpenGL or VTK?
>>> I understand that the PyQt package comes with a opengl module. What
>>> else would I need? I think I need to download opengl. but how? where?
>>> I have VTK and pyVTK installed, but I don't know how to use it in my
>>> code, as when I run it, an error says it can't find the vtk module.
>> 
>> VTK won't mix with Qt. And I don't think you need to download opengl - it
>> either comes with your system (or gfx-drivers), or not. I'm not sure if
> Qt
>> actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
>> PyOpenGL I guess.
> 
> VTK has explicit support for both Qt (ie. via C++) and PyQt.

Oh, I'm sorry for the FUD - they talk about Tk on their homepage.

Diez


From python.list at tim.thechases.com  Wed Jul  8 05:53:02 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Wed, 08 Jul 2009 04:53:02 -0500
Subject: count
In-Reply-To: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
Message-ID: <4A546C7E.503@tim.thechases.com>

> I wanted to sort column 2 in assending order  and I read whole file in array
> "data" and did the following:
> 
> data.sort(key = lambda fields:(fields[2]))
> 
> I have sorted column 2, however I want to count the numbers in the column 2.
> i.e. I want to know, for example, how many repeates of say '3' (first row,
> 2nd column in above data) are there in column 2.

I think you're trying to count in the wrong step -- I'd do the 
counting while you read the file in; not while you're trying to 
sort.  Maybe something like this untested file-wrapper:

   class Histo:
     def __init__(self, data, column):
       self.data = data
       self.column = column
       self.stats = defaultdict(int)
       self.exhausted = False
     def __iter__(self):
       if self.exhausted:
         raise StopIteration("Input exhausted")
       for line in self.data:
         self.stats[line[self.column]] += 1
         yield line
       self.exhausted = True
     def stats_so_far(self):
       return self.stats

   with file('in.txt') as f:
     r = csv.reader(f, delimiter='\t')
     h = Histo(r, 2)
     data = list(h) # slurp up the elements
   print repr(h.stats_so_far())
   data.sort(key = lambda fields: (fields[2]))

-tkc






From davea at ieee.org  Wed Jul  8 06:18:47 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 08 Jul 2009 06:18:47 -0400
Subject: Check file is locked?
In-Reply-To: <e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
Message-ID: <4A547287.8020507@ieee.org>

Rajat wrote:
> On Jul 8, 4:57 am, Lawrence D'Oliveiro <l... at geek-
> central.gen.new_zealand> wrote:
>   
>> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>>
>> Heimes wrote:
>>     
>>> By the way most operating systems don't lock a file when it's opened for
>>> reading or writing or even executed.
>>>       
>> The general conclusion seems to be that mandatory locking is more trouble
>> than it's worth.
>>     
>
> My OS is a windows XP sp3. All I'm trying to achieve is to close an
> application ( which could be a notepad, a wordpad or some other text
> editor) that have opened my file. Once the file is closed I can easily
> delete that file.
>
> I guess, if file is opened by one of that application, the file must
> be locked and so is the reason I cannot delete the file.
>
> Please suggest if this is fine.
>
>
>   
Neither Wordpad nor Notepad lock the files they have open, at least in 
my experience.  Specifically, I just tried it in XP Sp3.   I created a 
file, opened the file in one of the apps, then deleted the file before 
closing the app.

Word for Windows, on the other hand, has locked files for me in the 
past.  When I tried that one just now (on a text file, because that was 
easy), results were rather confusing.  It let me delete the file, but 
then when I tried to "save" it, it gave me a permissions error.  My 
experience with Winword has been that it's in a world of its own, best 
not messed with.  And this latest version (Office 2007 or somesuch) is 
so modern that it has removed the Help->About menu to make sure I can't 
even tell what version it is.  Next time I rebuild my system, I think 
I'll go back to Office 97.


But perhaps your question is intended to cover the general case.  You 
can get a program from sysinternals called   handle, which will list all 
the files (and other handles) opened by all the processes in the 
system.  You may be able to run that (with subprocess, or just from the 
commandline), and filter its output for the information you want.


DaveA


From dana_at_work at yahoo.com  Wed Jul  8 06:25:33 2009
From: dana_at_work at yahoo.com (dana)
Date: Wed, 8 Jul 2009 03:25:33 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
	<bb395e02-fe33-441e-8c01-27db196ef8e7@d9g2000prh.googlegroups.com>
Message-ID: <084fac41-364f-431c-9b8f-b57c3279f91d@x3g2000yqa.googlegroups.com>

On Jul 8, 12:30?am, John Machin <sjmac... at lexicon.net> wrote:
> Deprecated certainly doesn't mean removed.
> For a start, none of (DBI, ODBC, dbi, odbc) are standard Python-
> supplied modules. Perhaps you are referring to the odbc (and dbi) from
> the pywin32 package? Where did you get them from? If you can't
> remember, try this:

Thanks John. I mean the lower-case dbi and odbc modules from pywin32.
Sorry for being vague. I assumed incorrectly they were part of the
standard library because they came with pywin32.

> If this is what you're talking about, you should be asking on the
> pywin32 dicussion list (http://mail.python.org/mailman/listinfo/python-
> win32).

Thanks again.

> General advice: if you are thinking of upgrading your Python version,
> go straight to 2.6. odbc is AFAIK stuck at version 1.0 of the Python
> DB API; consider switching to pyodbc (http://code.google.com/p/
> pyodbc/)

Thanks thrice.

We "have" to use the version of Python our software vendor supports.
Presently, that's pywin32 version 2.5.

Dana


From piet at cs.uu.nl  Wed Jul  8 06:29:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 12:29:54 +0200
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
Message-ID: <m2d48bbh7h.fsf@cs.uu.nl>

>>>>> Fred Atkinson <fatkinson at mishmash.com> (FA) wrote:

>FA> On Tue, 07 Jul 2009 22:54:03 -0300, "Gabriel Genellina"
>FA> <gagsl-py2 at yahoo.com.ar> wrote:

>>> En Tue, 07 Jul 2009 22:45:24 -0300, Fred Atkinson <fatkinson at mishmash.com>  
>>> escribi?:
>>> 
>>>> Is there a Python function I can use to get the user's IP
>>>> address so I can display it on his browser?
>>> 
>>> There is a long distance between "Python" and "browser" - you'll have to  
>>> tell us what is in between the two.

>FA> 	I want to have a Web page come up (written in Python, cgi)
>FA> that returns the IP address of the browser (user's PC's IP address).  

>>> By example, do you have a server and the user connects to it? is it  
>>> running Python? how do you run the Python application?
>>> And why do you want to do that on the server side? Isn't easier to do that  
>>> on the client side? What about proxies? NAT?

>FA> 	Yes.  By CGI.  

>>> If using CGI, look at the REMOTE_ADDR environment variable.

>FA> 	I did look at REMOTE_ADDR but I've been unable to figure out
>FA> the correct way to code it.  I've tried a number of ways but I've been
>FA> unsuccessful.  

>FA> 	Ideally, I'd like to store the brower's IP address in a string
>FA> and then print the string on the Web page from a Python CGI script.  

Something like:

#! /usr/bin/env python

import cgi
from os import getenv

print "Content-type: text/html"
print

ipaddr = (getenv("HTTP_CLIENT_IP") or
      getenv("HTTP_X_FORWARDED_FOR") or
      getenv("HTTP_X_FORWARDED_FOR") or
      getenv("REMOTE_ADDR") or
      "UNKNOWN")

print ipaddr


-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nick at craig-wood.com  Wed Jul  8 06:30:01 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Wed, 08 Jul 2009 05:30:01 -0500
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
	<006eb2e3$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <slrnh58qbj.mjl.nick@irishsea.home.craig-wood.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
>  On Mon, 06 Jul 2009 15:02:26 -0700, Michael Mossey wrote:
> 
> > On Jul 6, 2:47?pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
> >> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
> >>
> >> > What is required in a python program to make sure it catches a
> >> > control-
> >> > c on the command-line? Do some i/o? The OS here is Linux.
> >>
> >> You can use a try/except to catch a KeyboardInterrupt exception, or you
> >> can trap it using the signal
> >> module:http://docs.python.org/library/signal.html
> >>
> >> You want to trap SIGINT.
> >>
> >> HTH
> >> Philip
> > 
> > Thanks to both of you. However, my question is also about whether I need
> > to be doing i/o or some similar operation for my program to notice in
> > any shape or form that Control-C has been pressed. In the past, I've
> > written Python programs that go about their business ignoring Ctrl-C.
> 
>  I bet that somewhere in your code you have something like:
> 
> 
>  for x in really_big_list:
>      try:
>          long_running_process(x)
>      except:
>          continue
> 
> 
>  If that's what you're doing, stop! The correct way is:
> 
> 
>  for x in really_big_list:
>      try:
>          long_running_process(x)
>      except Exception:
>          # Let KeyboardInterrupt and SystemExit through.
>          continue

Note that it is a relatively recent change (in python 2.5) which made
KeyboardInterrupt not a child of Exception

ncw at dogger:~$ python2.4
Python 2.4.6 (#2, Feb 17 2009, 20:01:48)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
Loaded customisations from '/home/ncw/.pystartup'
>>> isinstance(KeyboardInterrupt(), Exception)
True
>>>

ncw at dogger:~$ python2.5
Python 2.5.4 (r254:67916, Feb 17 2009, 20:16:45)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
Loaded customisations from '/home/ncw/.pystartup'
>>> isinstance(KeyboardInterrupt(), Exception)
False
>>>

>  for x in really_big_list:
>      try:
>          long_running_process(x)
>      except (KeyboardInterrupt, SystemExit):
>          print "User requested exit... shutting down now"
>          cleanup()
>          raise
>      except Exception:
>          continue

That is the backwards compatible way

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From bearophileHUGS at lycos.com  Wed Jul  8 07:20:56 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Wed, 8 Jul 2009 04:20:56 -0700 (PDT)
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com> 
	<mailman.2829.1247043839.8015.python-list@python.org>
Message-ID: <050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>

Vilya Harvey:
> from itertools import groupby
> for x, g in groupby([fields[1] for fields in data]):
> ? ? print x, len(tuple(g))

Avoid that len(tuple(g)), use something like the following, it's lazy
and saves some memory.


def leniter(iterator):
    """leniter(iterator): return the length of a given
    iterator, consuming it, without creating a list.
    Never use it with infinite iterators.

    >>> leniter()
    Traceback (most recent call last):
      ...
    TypeError: leniter() takes exactly 1 argument (0 given)
    >>> leniter([])
    0
    >>> leniter([1])
    1
    >>> leniter(iter([1]))
    1
    >>> leniter(x for x in xrange(100) if x%2)
    50
    >>> from itertools import groupby
    >>> [(leniter(g), h) for h,g in groupby("aaaabccaadeeee")]
    [(4, 'a'), (1, 'b'), (2, 'c'), (2, 'a'), (1, 'd'), (4, 'e')]

    >>> def foo0():
    ...     if False: yield 1
    >>> leniter(foo0())
    0

    >>> def foo1(): yield 1
    >>> leniter(foo1())
    1
    """
    # This code is faster than:  sum(1 for _ in iterator)
    if hasattr(iterator, "__len__"):
        return len(iterator)
    nelements = 0
    for _ in iterator:
        nelements += 1
    return nelements

Bye,
bearophile


From no.email at please.post  Wed Jul  8 07:59:19 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 11:59:19 +0000 (UTC)
Subject: Fractions as result from divisions (was: Re: tough-to-explain
	Python)
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<c75ei6-e0i.ln1@satorlaser.homedns.org>
Message-ID: <h321mn$2bg$1@reader1.panix.com>

In <c75ei6-e0i.ln1 at satorlaser.homedns.org> Ulrich Eckhardt <eckhardt at satorlaser.com> writes:

>Bearophile wrote:
>> For example a novice wants to see 124 / 38 to return the 62/19
>> fraction and not 3 or 3.263157894736842 :-)

>Python has adopted the latter of the three for operator / and the the second
>one for operator //. I wonder if it was considered to just return a
>fraction from that operation.

http://www.python.org/dev/peps/pep-0239/

kj



From mail at microcorp.co.za  Wed Jul  8 08:15:08 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 8 Jul 2009 14:15:08 +0200
Subject: Remoting over SSH
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <007901c9ffc5$cef87780$0d00a8c0@Hendrik>

"Hussein B" <hubaghdadi at gmail.com> wrote:

> Hey,
> I want to perform commands on a remote server over SSH.
> What do I need?
> Thanks.

Access privileges for the remote machine.

- Hendrik





From no.email at please.post  Wed Jul  8 08:23:50 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 12:23:50 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
Message-ID: <h3234l$aod$1@reader1.panix.com>

In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com> Simon Forman <sajmikins at gmail.com> writes:

>Frankly, I'm of the impression that it's a mistake not to start
>teaching programming with /the bit/ and work your way up from there.
>I'm not kidding. I wrote a (draft) article about this: "Computer
>Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4

>I really think the only good way to teach computers and programming is
>to start with a bit, and build up from there. "Ontology recapitulates
>phylogeny"


I happen to be very receptive to this point of view.  I had the
benefit of that sort of training (one of the first computer courses
I took started, believe it or not, with Turing machines, through
coding in machine language, and compiler theory, and all the way
up to dabbling with Unix!), and I suspect that the reason it is
sometimes difficult for me to explain even relatively simple-looking
things to others is that I have this background that I unconsciously,
and incorrectly, take for granted in others...  There is this
persistent idea "out there" that programming is a very accessible
skill, like cooking or gardening, anyone can do it, and even profit
from it, monetarily or otherwise, etc., and to some extent I am
actively contributing to this perception by teaching this course
to non-programmers (experimental biologists to be more precise),
but maybe this idea is not entirely true...  Maybe, to get past
the most amateurish level, one has to, one way or another, come
face-to-face with bits, compilers, algorithms, and all the rest
that real computer scientists learn about in their formal training...

kj



From p.f.moore at gmail.com  Wed Jul  8 08:33:50 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Wed, 8 Jul 2009 13:33:50 +0100
Subject: DBI module deprecated at Python 2.5--what to use in its place?
In-Reply-To: <084fac41-364f-431c-9b8f-b57c3279f91d@x3g2000yqa.googlegroups.com>
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
	<bb395e02-fe33-441e-8c01-27db196ef8e7@d9g2000prh.googlegroups.com>
	<084fac41-364f-431c-9b8f-b57c3279f91d@x3g2000yqa.googlegroups.com>
Message-ID: <79990c6b0907080533v54f97099oabc77a8d146fe5e7@mail.gmail.com>

2009/7/8 dana <dana_at_work at yahoo.com>:
> On Jul 8, 12:30?am, John Machin <sjmac... at lexicon.net> wrote:
>> Deprecated certainly doesn't mean removed.
>> For a start, none of (DBI, ODBC, dbi, odbc) are standard Python-
>> supplied modules. Perhaps you are referring to the odbc (and dbi) from
>> the pywin32 package? Where did you get them from? If you can't
>> remember, try this:
>
> Thanks John. I mean the lower-case dbi and odbc modules from pywin32.
> Sorry for being vague. I assumed incorrectly they were part of the
> standard library because they came with pywin32.

pywin32 isn't part of the standard library, either - it just feels
like it if you're on Windows :-)

As you've already seen, the Python-Win32 list is probably of more use
to you: http://mail.python.org/mailman/listinfo/python-win32

Paul.


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 08:43:55 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 12:43:55 GMT
Subject: Fractions as result from divisions (was: Re: tough-to-explain
	Python)
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<c75ei6-e0i.ln1@satorlaser.homedns.org>
Message-ID: <00706f76$0$9711$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 11:24:28 +0200, Ulrich Eckhardt wrote:

> Bearophile wrote:
>> For example a novice wants to see 124 / 38 to return the 62/19 fraction
>> and not 3 or 3.263157894736842 :-)
> 
> Python has adopted the latter of the three for operator / and the the
> second one for operator //.

Up until a few years ago, / would return the integer division if both 
arguments where ints or longs, and // didn't even exist. Even in Python 
2.6, you still need to do

from __future__ import division 

to get the behaviour you describe.


> I wonder if it was considered to just return
> a fraction from that operation.

Because of his experience with ABC, Guido dislikes using fractions for 
standard arithmetic. He was resistant to even allowing the rational 
module be added to the standard library.

The problem with fractions is that, unless you're very careful, repeated 
arithmetic operations on numbers ends up giving you fractions like 

498655847957/569892397664

instead of the 7/8 you were expecting. Not only is that ugly, but it 
becomes slower and slower as the denominator and numerator become larger.

At least, that was Guido's experience.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 08:46:28 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 12:46:28 GMT
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2824.1247036789.8015.python-list@python.org>
Message-ID: <0070700f$0$9711$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 00:06:11 -0700, Dennis Lee Bieber wrote:

> 	Also, some applications may still have the file open, but Windows
> allows one to make copies of that file...


Not always though... some applications open files for exclusive read 
access.


-- 
Steven


From zephyrfalcon!NO_SPAM! at gmail.com  Wed Jul  8 08:51:30 2009
From: zephyrfalcon!NO_SPAM! at gmail.com (Hans Nowak)
Date: Wed, 08 Jul 2009 08:51:30 -0400
Subject: Fractions as result from divisions
In-Reply-To: <c75ei6-e0i.ln1@satorlaser.homedns.org>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
	<c75ei6-e0i.ln1@satorlaser.homedns.org>
Message-ID: <4A549652.9070408@gmail.com>

Ulrich Eckhardt wrote:
> Bearophile wrote:
>> For example a novice wants to see 124 / 38 to return the 62/19
>> fraction and not 3 or 3.263157894736842 :-)
> 
> Python has adopted the latter of the three for operator / and the the second
> one for operator //. I wonder if it was considered to just return a
> fraction from that operation.

http://python-history.blogspot.com/2009/03/problem-with-integer-division.html

"For example, in ABC, when you divided two integers, the result was an exact 
rational number representing the result. In Python however, integer division 
truncated the result to an integer.

In my experience, rational numbers didn't pan out as ABC's designers had hoped. 
A typical experience would be to write a simple program for some business 
application (say, doing one?s taxes), and find that it was running much slower 
than expected. After some debugging, the cause would be that internally the 
program was using rational numbers with thousands of digits of precision to 
represent values that would be truncated to two or three digits of precision 
upon printing. This could be easily fixed by starting an addition with an 
inexact zero, but this was often non-intuitive and hard to debug for beginners."

-- 
Hans Nowak (zephyrfalcon at gmail dot com)
http://4.flowsnake.org/


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul  8 09:10:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 08 Jul 2009 13:10:23 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
Message-ID: <007075aa$0$9711$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 12:23:50 +0000, kj wrote:

> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com>
> Simon Forman <sajmikins at gmail.com> writes:
> 
>>Frankly, I'm of the impression that it's a mistake not to start teaching
>>programming with /the bit/ and work your way up from there. I'm not
>>kidding. I wrote a (draft) article about this: "Computer Curriculum"
>>http://docs.google.com/View?id=dgwr777r_31g4572gp4
> 
>>I really think the only good way to teach computers and programming is
>>to start with a bit, and build up from there. "Ontology recapitulates
>>phylogeny"
> 
> 
> I happen to be very receptive to this point of view.
[...]
> There is this persistent idea "out there" that
> programming is a very accessible skill, like cooking or gardening,
> anyone can do it, and even profit from it, monetarily or otherwise,
> etc., and to some extent I am actively contributing to this perception
> by teaching this course to non-programmers (experimental biologists to
> be more precise), but maybe this idea is not entirely true...  

There is some evidence that 30-60% of people simply cannot learn to 
program, no matter how you teach them:

http://www.codinghorror.com/blog/archives/000635.html
http://www.cs.mdx.ac.uk/research/PhDArea/saeed/

I'm sympathetic to the idea, but not entirely convinced. Perhaps the 
problem isn't with the students, but with the teachers, and the 
languages: 

http://www.csse.monash.edu.au/~damian/papers/PDF/SevenDeadlySins.pdf

(My money is that it's a little of both.)


> Maybe, to
> get past the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest that
> real computer scientists learn about in their formal training...

The "No True Scotsman" fallacy.

There's nothing amateurish about building software applications that 
work, with well-designed interfaces and a minimum of bugs, even if you've 
never heard of Turing Machines.


-- 
Steven


From lucascarvalho at gmail.com  Wed Jul  8 09:11:35 2009
From: lucascarvalho at gmail.com (Lucas Carvalho)
Date: Wed, 08 Jul 2009 15:11:35 +0200
Subject: Remoting over SSH
In-Reply-To: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
Message-ID: <4A549B07.2090402@gmail.com>

Hussein B wrote:
> Hey,
> I want to perform commands on a remote server over SSH.
> What do I need?
> Thanks.
>   
Hi,
 If you want to use the SSH2 protocol into a python code, you should
take a look at this module: paramiko [1].

[1] http://www.lag.net/paramiko/

Regards,
 Lucas.


From pruebauno at latinmail.com  Wed Jul  8 09:23:57 2009
From: pruebauno at latinmail.com (nn)
Date: Wed, 8 Jul 2009 06:23:57 -0700 (PDT)
Subject: library search path when compiling python
References: <13d8e508-0f09-43c3-acfd-b260e41d9cd6@a36g2000yqc.googlegroups.com>
	<mailman.2794.1246997166.8015.python-list@python.org>
Message-ID: <11e4f2f2-a32f-4671-a457-7cdd928d29fb@a7g2000yqk.googlegroups.com>

On Jul 7, 4:06?pm, Christian Heimes <li... at cheimes.de> wrote:
> nn wrote:
> > I am trying to compile python with ssl support but the libraries are
> > not in /usr/lib but in /opt/freeware/lib. How do I add that folder to
> > the default library search path?
>
> > It looks like configure --libdir=DIR might do the job but I don't want
> > to replace the default lib search path, just add an additional folder
> > to it.
>
> You didn't mention your OS. On Linux you can set the environment
> variable LD_RUN_PATH prior to compiling Python. The env var sets the
> rpath for the linker. See man ld(1) for details.
>
> Christian

Sorry I didn't realize that was OS specific. I am on AIX 5.3.


From no.email at please.post  Wed Jul  8 09:27:34 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 13:27:34 +0000 (UTC)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
Message-ID: <h326s6$5sl$1@reader1.panix.com>

In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com> Simon Forman <sajmikins at gmail.com> writes:

>I'm not kidding. I wrote a (draft) article about this: "Computer
>Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4

Very cool.

kj


From aahz at pythoncraft.com  Wed Jul  8 09:40:34 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 06:40:34 -0700
Subject: Newbie needs help
References: <8694d66b-307f-4f35-9bad-dd78e553ac8c@q11g2000yqi.googlegroups.com>
	<50f98a4c0907070718v31331f63tf0bdae930b22d01e@mail.gmail.com>
	<527BE7864AF97047BD9F4DEA26124D2B04906DC3@cos-us-mb01.cos.agilent.com>
	<mailman.2781.1246979580.8015.python-list@python.org>
Message-ID: <h327ki$8s6$1@panix3.panix.com>

In article <mailman.2781.1246979580.8015.python-list at python.org>,
Pablo Torres N. <tn.pablo at gmail.com> wrote:
>
>Give this one a try too: http://www.mikeash.com/getting_answers.html
>It doesn't talk down to you...as much :P

Nice!  I'll try remembering that one.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From p.f.moore at gmail.com  Wed Jul  8 09:47:48 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Wed, 8 Jul 2009 14:47:48 +0100
Subject: tough-to-explain Python
In-Reply-To: <h3234l$aod$1@reader1.panix.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
Message-ID: <79990c6b0907080647l22dce38epf03709b1119b2529@mail.gmail.com>

2009/7/8 kj <no.email at please.post>:
> There is this
> persistent idea "out there" that programming is a very accessible
> skill, like cooking or gardening, anyone can do it, and even profit
> from it, monetarily or otherwise, etc., and to some extent I am
> actively contributing to this perception by teaching this course
> to non-programmers (experimental biologists to be more precise),
> but maybe this idea is not entirely true... ?Maybe, to get past
> the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest
> that real computer scientists learn about in their formal training...

Look at it another way. Experimental biologists don't want to program,
they want to use computers to do experimental biology. It's a tool,
and they (quite reasonably) don't *care* about robustness,
portability, etc. Or even about programming, to be honest.

In the context of the original question, it's entirely reasonable (in
my view) to tell this audience "if the code does something weird you
don't understand, either ignore it and find another way or dig into
the manuals and experiment if you care". They'd very quickly find a =
a + b as a less confusing alternative to a += b. (As has been pointed
out earlier, to some extent a += b is quite an advanced construct -
after all, it's essentially an optimisation of a = a + b).

Biologists don't expect me to understand their discipline before I can
plant seeds in my garden, after all. (And when I do plant seeds, I
usually get far more surprising results than I could get from a += b
:-))

Paul.


From pruebauno at latinmail.com  Wed Jul  8 09:55:18 2009
From: pruebauno at latinmail.com (nn)
Date: Wed, 8 Jul 2009 06:55:18 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<mailman.2796.1246997332.8015.python-list@python.org> 
	<h30e3t$g56$2@reader1.panix.com>
Message-ID: <d0f7d666-d4f4-4b30-bf18-d2d1d5d805ff@y19g2000yqy.googlegroups.com>

On Jul 7, 5:18?pm, kj <no.em... at please.post> wrote:
> In <mailman.2796.1246997332.8015.python-l... at python.org> Chris Rebert <c... at rebertia.com> writes:
>
> >You might find the following helpful (partially):
> >http://effbot.org/zone/call-by-object.htm
>
> Extremely helpful. ?Thanks! ?(I learned more from it than someone
> who will teach the stuff would care to admit...)
>
> And it confirmed Paul Graham's often-made assertion that all of
> programming language design is still catching up to Lisp...
>
> kj

One possibility is to avoid teaching mutable datatypes at the
beginning (i.e. no lists,dicts and sets), then you would have
something more lispish. You would have to use tuples instead of lists
for everything. That avoids the gotchas of mutable types at the cost
of efficiency.

Python is not a purist language but rather walks a fine line between
high flexible abstractions and simple fast implementation.


From no.email at please.post  Wed Jul  8 10:04:35 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 14:04:35 +0000 (UTC)
Subject: The meaning of "=" (Was: tough-to-explain Python)
Message-ID: <h3291j$mfu$1@reader1.panix.com>

In <h30e3t$g56$2 at reader1.panix.com> kj <no.email at please.post> writes:

>I had not realized how *profoundly* different the meaning of the
>"=" in Python's

>  spam = ham

>is from the "=" in its

>  spam[3] = ham[3]


To clarify, this comes from my reading of Fredrik Lundh's pages
"Python Objects" (http://effbot.org/zone/python-objects.htm) and
"Call By Object" (http://effbot.org/zone/call-by-object.htm).
(Thanks to Chris Rebert for the pointer!)

In the first one of these pages, Lundh writes:

[START OF LENGTHY QUOTE]

  Assignment statements modify namespaces, not objects.

  In other words,

  name = 10

  means that you're adding the name 'name' to your local namespace,
  and making it refer to an integer object containing the value
  10.

  If the name is already present, the assignment replaces the
  original name:

  name = 10
  name = 20

  means that you're first adding the name 'name' to the local
  namespace, and making it refer to an integer object containing
  the value 10. You're then replacing the name, making it point to
  an integer object containing the value 20. The original '10'
  object isn't affected by this operation, and it doesn't care.

  In contrast, if you do:

  name = []
  name.append(1)

  you're first adding the name 'name' to the local namespace, making
  it refer to an empty list object. This modifies the namespace.
  You're then calling a method on that object, telling it to append
  an integer object to itself. This modifies the content of the
  list object, but it doesn't touch the namespace, and it doesn't
  touch the integer object.

  Things like name.attr and name[index] are just syntactic sugar
  for method calls. The first corresponds to __setattr__/__getattr__,
  the second to __setitem__/__getitem__ (depending on which side
  of the assignment they appear).

[END OF LENGTHY QUOTE]

Therefore, extending just a bit beyond Lundh's explanation, if we
did:

name = []
name.append(1)
name[0] = 3

...the second assignment would amount to a method call on the object
called 'name', an operation of a very different nature (according
to Lundh) from the first assignment, which is a modification of a
namespace.

In the second one of these pages, Lundh makes a very similar point
(third post from the bottom).

But note that Lundh appears to be contradicting himself somewhat
when he writes "Assignment statements modify namespaces, not
objects."  If by "assignment statements" he means ones consisting
of a left operand, a "=", and a right operand, then according to
the rest of what he writes on this subject, this assertion applies
only to *some* assignment statements, namely those of the form

  <identifier> = <expression>

and not to those like, for example,

  <identifier>[<expression>] = <expression>

or

  <identifier>.<identifier> = <expression>

The former are syntatic sugar for certain namespace modifications
that leave objects unchanged.  The latter are syntactic sugar for
certain object-modifying method calls that leave namespaces unchanged.

At least this is how I interpret what Lundh writes.

kj



From pdpinheiro at gmail.com  Wed Jul  8 10:06:09 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Wed, 8 Jul 2009 07:06:09 -0700 (PDT)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> 
	<h2lb2a$9pt$1@reader1.panix.com> <zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org> 
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com> 
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org> 
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
	<91b1c921-52bf-4fd3-8361-4620fff93821@c9g2000yqm.googlegroups.com>
	<7xab3gz7ss.fsf@ruckus.brouhaha.com>
	<1695009b-12e9-426a-9aab-8073d4303d3b@t13g2000yqt.googlegroups.com>
	<1f09e856-bd04-4d27-bf51-5d67953a7e13@y7g2000yqa.googlegroups.com> 
	<7xskh83r1v.fsf@ruckus.brouhaha.com>
Message-ID: <9b819fa8-92f0-4b73-866f-95097d0a5b03@c1g2000yqi.googlegroups.com>

On Jul 8, 2:24?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> pdpi <pdpinhe... at gmail.com> writes:
> > ? ? while abs(func(guess) - target) > epsilon:
> > ? ? ? ? guess = (lo + hi) / 2.
> > ? ? ? ? if sense * func(guess) > sense * target:
> > ? ? ? ? ? ? hi = guess
> > ? ? ? ? elif sense * func(guess) < sense * target:
> > ? ? ? ? ? ? lo = guess
> > ? ? ? ? elif lo == hi:
> > ? ? ? ? ? ? return None
> > ? ? return guess
>
> That is completely confusing. ?I get the, er, impression that "sense"
> is supposed to change during the loop, and it takes much head
> scratching to tell whether what you have there is right or not. ?Also,
> it calls func 3 times on each loop, which could be extremely slow.
> You don't know what func does, so eliminating 2/3 of the calls to it
> is not a micro-optimization--it could be a major time saving.
>
> Yet another version:
>
> ? ? def _binary_search(x0, x1, func, target, epsilon):
> ? ? ? ? y0,y1 = func(x0), func(x1)
> ? ? ? ? while abs(y1 - target) > epsilon:
> ? ? ? ? ? ? if x0 == x1 or cmp(y0,target) == cmp(y1,target):
> ? ? ? ? ? ? ? ? return None
> ? ? ? ? ? ? xn = (x0 + x1) / 2.
> ? ? ? ? ? ? yn = func(xn)
> ? ? ? ? ? ? if cmp(yn,target) == cmp(y0,target):
> ? ? ? ? ? ? ? ?x0,y0 = xn,yn
> ? ? ? ? ? ? else:
> ? ? ? ? ? ? ? ?x1,y1 = xn,yn
> ? ? ? ? return x1

micro-optimization was perhaps too harsh, but it is an optimization
that's not obvious for the newbie, and one best learnt from experience
rather than having it spoon fed. I'll restate: you should start with
the cleanest code possible and mangle it for performance. Then again,
that implicitly assumes that f(x) is more readable than y, which is
really a matter of taste...


From futurebase at gmx.at  Wed Jul  8 10:44:37 2009
From: futurebase at gmx.at (Daniel Austria)
Date: Wed, 8 Jul 2009 07:44:37 -0700 (PDT)
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
Message-ID: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>

Hi python - hackers,

just one question. How can i remove all 0 values in a list? Sure - i
can loop over it, but that s not a neat style.  list.remove() will
only remove the first occurence. Doing that while no exception is
raised is also uncool, right?

Some suggestions?


Best,
Dan


From paul at boddie.org.uk  Wed Jul  8 10:53:44 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Wed, 8 Jul 2009 07:53:44 -0700 (PDT)
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
Message-ID: <0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>

On 8 Jul, 16:04, kj <no.em... at please.post> wrote:
>
> ? <identifier> = <expression>
>
> and not to those like, for example,
>
> ? <identifier>[<expression>] = <expression>
>
> or
>
> ? <identifier>.<identifier> = <expression>
>
> The former are syntatic sugar for certain namespace modifications
> that leave objects unchanged. ?The latter are syntactic sugar for
> certain object-modifying method calls that leave namespaces unchanged.

Almost. The latter can modify namespaces - the objects themselves -
but through properties or dynamic attribute access, they may choose
not to modify such a namespace. Really, we can phrase assignment (=)
as follows:

<thing> = <expression> # make <thing> refer to the result of
<expression>

Here, <thing> has to provide something that can be made to refer to
something else, such as a name within a namespace - the first and last
of your cases - or an item or slice within a sequence - the special
second case which is actually handled differently from the other
cases.

Meanwhile, the <expression> will always provide an object to refer to,
never anything of the nature of <thing> referring to something else.
In other words, if you have this...

x[1] = y[2]

...then the <expression> which is y[2] will yield an object which is
then assigned to x[1]. The concept of y[2] is not assignable - it must
be fully evaluated and produce the object at location #2 in the
sequence for assignment.

I suppose you could say that the left-hand side <thing> is like a sign
on a signpost which always points to a real place, not another sign on
a signpost. You could stretch this analogy by treating sequences as
signposts holding many signs, each adjustable to point to something
different. Since signposts (not the individual signs) are located in
real places, they would naturally be acceptable as targets of
assignments: where the signs are allowed to point to. Indeed, this
would be a world of signposts with the occasional primitive value
mixed in to keep weary travellers interested. ;-)

Paul


From mabdelkader at gmail.com  Wed Jul  8 10:54:09 2009
From: mabdelkader at gmail.com (ma)
Date: Wed, 8 Jul 2009 10:54:09 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>

filter(lambda x: x, your_list)

On Wed, Jul 8, 2009 at 10:44 AM, Daniel Austria <futurebase at gmx.at> wrote:

> Hi python - hackers,
>
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.  list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
>
> Some suggestions?
>
>
> Best,
> Dan
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/f2433031/attachment-0001.html>

From bruno.42.desthuilliers at websiteburo.invalid  Wed Jul  8 10:57:16 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Wed, 08 Jul 2009 16:57:16 +0200
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <4a54b3bf$0$405$426a74cc@news.free.fr>

Daniel Austria a ?crit :
> Hi python - hackers,
> 
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.  list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
> 
> Some suggestions?

the_list = [0, 0, 0, 1, 1, 1, 0]

# Simple solution
print [x for x in the_list if x != 0]

# if you want to mutate the list 'in place':
the_list[:] = [x for x in the_list if x != 0]
print the_list

HTH


From djames.suhanko at gmail.com  Wed Jul  8 10:59:38 2009
From: djames.suhanko at gmail.com (Djames Suhanko)
Date: Wed, 8 Jul 2009 11:59:38 -0300
Subject: Remoting over SSH
In-Reply-To: <007901c9ffc5$cef87780$0d00a8c0@Hendrik>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
	<007901c9ffc5$cef87780$0d00a8c0@Hendrik>
Message-ID: <fd9e6bba0907080759u344dd40bwb2cd11fbd4e6f95e@mail.gmail.com>

Hello!
 I wrote a litle program that send commands to many cluster nodes:

#!/usr/bin/env python
#By: Djames Suhanko

#servers list

sincroniza =["server1.domain","server2.domain", "server3.domain"]

import pexpect
import sys
from threading import Thread

#the user and pass can be in ini file.

#Test parameters list

try:
    if sys.argv[3]:
        pass
except:
    print  "Use: " + "script" + " <command> <user> <pass>"
    sys.exit()

#This function send  the command in argument
def executor(command,username,password,server):
    a = 'ssh ' + username + '@' + server
    foo = pexpect.spawn(a)
    foo.expect('.*ssword:')
    foo.sendline(password)
    foo.sendline('su')
    foo.expect('.*sword:')
    foo.sendline('root_password_here')
    foo.sendline(command + '&& exit')
    print "command to: " + server + "..........[OK]"
    foo.sendline('exit')
    foo.expect('.*osed.')
    foo.interact()

#make a list
tasks = []

#theading loop
for i in sincroniza:
    t = Thread(target=executor,args=(sys.argv[1],sys.argv[2],sys.argv[3],i))
    t.start()
    tasks.append(t)

#wait the end
for t in tasks:
    t.join()

it's all!
On Wed, Jul 8, 2009 at 9:15 AM, Hendrik van Rooyen<mail at microcorp.co.za> wrote:
> "Hussein B" <hubaghdadi at gmail.com> wrote:
>
>> Hey,
>> I want to perform commands on a remote server over SSH.
>> What do I need?
>> Thanks.
>
> Access privileges for the remote machine.
>
> - Hendrik
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Djames Suhanko
LinuxUser 158.760


From charles at declareSub.com  Wed Jul  8 11:02:16 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Wed, 8 Jul 2009 11:02:16 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
Message-ID: <A2C7533A-3BCF-493E-8FDA-900F82177757@declareSub.com>


On Jul 8, 2009, at 10:54 AM, ma wrote:

> filter(lambda x: x, your_list)
>
> On Wed, Jul 8, 2009 at 10:44 AM, Daniel Austria <futurebase at gmx.at>  
> wrote:
> Hi python - hackers,
>
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.  list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
>
> Some suggestions?
>


L = [0, 0, 0, 1, 1, 1, 0]
M = [x for x in L if x !=0]


Charles Yeomans
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/3e9ee60c/attachment-0001.html>

From darcy at druid.net  Wed Jul  8 11:03:15 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Wed, 8 Jul 2009 11:03:15 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
Message-ID: <20090708110315.634de5d2.darcy@druid.net>

On Wed, 8 Jul 2009 10:54:09 -0400
ma <mabdelkader at gmail.com> wrote:
> filter(lambda x: x, your_list)

Or...

 [x for x in your_list if x]

I'm not sure which one is more efficient but I like the syntax of the
latter.  A smart person could probably figure it out even without
knowing Python syntax.  Clarity is trump.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From fridrik at pyth.net  Wed Jul  8 11:03:56 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Wed, 8 Jul 2009 15:03:56 +0000
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
Message-ID: <D0104C46-E4DE-473D-9B15-8A189945D6F0@pyth.net>


ma wrote:
> filter(lambda x: x, your_list)

Good call! Equivalent but more efficient:

  filter(None, your_list)

Regards,
Fri?rik M?r

From deets at nospam.web.de  Wed Jul  8 11:06:23 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 08 Jul 2009 17:06:23 +0200
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <7bjqndF22l519U1@mid.uni-berlin.de>

Daniel Austria wrote:

> Hi python - hackers,
> 
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style.

Why not? If you need to potentially look at *all* elements of a list,
nothing but a loop will take you there.

OTOH, your proposed "remove until nothing is found"-thingy will become
quadratic in behavior, as remove also loops over the list - so if you have
list with say 10 ones followed by 10 zeros, you will loop ten times for 11
elements, which is in the order of (n/2)**2.

Diez


From nachogomez at gmail.com  Wed Jul  8 11:14:36 2009
From: nachogomez at gmail.com (=?UTF-8?B?UmHDumwgR8OzbWV6IEMu?=)
Date: Wed, 8 Jul 2009 10:44:36 -0430
Subject: Remoting over SSH
In-Reply-To: <fd9e6bba0907080759u344dd40bwb2cd11fbd4e6f95e@mail.gmail.com>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
	<007901c9ffc5$cef87780$0d00a8c0@Hendrik>
	<fd9e6bba0907080759u344dd40bwb2cd11fbd4e6f95e@mail.gmail.com>
Message-ID: <684b0a740907080814t4f4911e1u9b417aaaba76e44a@mail.gmail.com>

You also could use
TwistedConch<http://twistedmatrix.com/trac/wiki/TwistedConch>,
which is an implementation of the SSH2 protocol for Python. I've done
something with it, you can read my first questions on the TwistedConch list
here<http://twistedmatrix.com/pipermail/twisted-python/2007-October/016121.html>
.

Hope that helps...


-- 
Nacho
Linux Counter #156439
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/c2cde64f/attachment-0001.html>

From no.email at please.post  Wed Jul  8 11:42:09 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 15:42:09 +0000 (UTC)
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
Message-ID: <h32eoh$ql8$1@reader1.panix.com>

In <0778f257-d36c-4e13-93ea-bf8d448c82e2 at b15g2000yqd.googlegroups.com> Paul Boddie <paul at boddie.org.uk> writes:

>On 8 Jul, 16:04, kj <no.em... at please.post> wrote:
>>
>> =A0 <identifier> =3D <expression>
>>
>> and not to those like, for example,
>>
>> =A0 <identifier>[<expression>] =3D <expression>
>>
>> or
>>
>> =A0 <identifier>.<identifier> =3D <expression>
>>
>> The former are syntatic sugar for certain namespace modifications
>> that leave objects unchanged. =A0The latter are syntactic sugar for
>> certain object-modifying method calls that leave namespaces unchanged.

>Almost. The latter can modify namespaces - the objects themselves -
>but through properties or dynamic attribute access, they may choose
>not to modify such a namespace. Really, we can phrase assignment (=3D)
>as follows:

><thing> =3D <expression> # make <thing> refer to the result of
><expression>

>Here, <thing> has to provide something that can be made to refer to
>something else, such as a name within a namespace - the first and last
>of your cases - or an item or slice within a sequence - the special
>second case which is actually handled differently from the other
>cases.

Thanks for this correction.

OK, so, scratching from my original post the case

<identifier>.<identifier> = <expression>

(as being a special case of <identifier> = <expression>), still,
to the extent that I understand your post, the "=" in

  x = 1

means something fundamentally different (in terms of Python's
underlying implementation) from the "=" in

  y[0] = 1

No?

>You could stretch this analogy by treating sequences as
>signposts holding many signs, each adjustable to point to something
>different.

Notionally, yes, I can see that, but there's no counterpart of this
analogy at the level of Python's implementation.  The "x" above is
a sign, as you put it, i.e. an entry in a namespace, but "y[0]"
is, in essence, a method call.

kj


From aahz at pythoncraft.com  Wed Jul  8 11:44:32 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 08:44:32 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
Message-ID: <h32et0$ika$1@panix3.panix.com>

In article <0778f257-d36c-4e13-93ea-bf8d448c82e2 at b15g2000yqd.googlegroups.com>,
Paul Boddie  <paul at boddie.org.uk> wrote:
>
>Almost. The latter can modify namespaces - the objects themselves -
>but through properties or dynamic attribute access, they may choose
>not to modify such a namespace. Really, we can phrase assignment (=)
>as follows:
>
><thing> = <expression> # make <thing> refer to the result of <expression>

Right, except s/thing/target/

http://docs.python.org/reference/simple_stmts.html#assignment-statements
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From matt0177 at gmail.com  Wed Jul  8 11:54:36 2009
From: matt0177 at gmail.com (Matthew Edmondson)
Date: Wed, 8 Jul 2009 08:54:36 -0700
Subject: Python Error from Apress book
In-Reply-To: <4A54687A.6010004@ieee.org>
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
	<4A5345B1.8050306@ieee.org>
	<op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
	<4A54687A.6010004@ieee.org>
Message-ID: <8e2cbd660907080854p65bad365p54ccdad4771786a6@mail.gmail.com>

I'm running XP SP3. The program now works great from either of the
directories, as long as include 'python' before it. As far as looking at the
error with stack trace, I really don't know enough yet to know how to do
that. I'm running the file from command line, because I'm not sure how to
run it referencing other files from idle. Lot to learn.....

Once again, thanks a ton for all of the help.

Matt

On Wed, Jul 8, 2009 at 2:35 AM, Dave Angel <davea at ieee.org> wrote:

>
>
> Gabriel Genellina wrote:
>
>> <div class="moz-text-flowed" style="font-family: -moz-fixed">En Tue, 07
>> Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
>>
>>> Gabriel Genellina wrote:
>>>
>>>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com>
>>>> escribi?:
>>>>
>>>
>>  When I try to run the command as outlined in
>>>>> the book "simple_markup2.py < test_input.txt > test_output.html i get
>>>>> the
>>>>> following error every time.
>>>>>
>>>>> IOError: [Errno 9] Bad file descriptor
>>>>>
>>>>
>>>> That's a Windows problem. When you execute the script as itself (either
>>>> as you do in the command line, or by double-clicking on it), it doesn't have
>>>> valid standard handles.
>>>> You have to invoke Python explicitely:
>>>>
>>>> python simple_markup2.py < test_input.txt > test_output.html
>>>>
>>>> (you may need to specify the full path to python.exe, or add the
>>>> directory where Python is installed to your system PATH).
>>>>
>>>>  I use stdout this way all the time, with no problem (python 2.6,
>>> Windows XP).  But as you point out, stdin redirection doesn't seem to work
>>> using the file associations.  I do get a different error though. When I look
>>> at sys.stdin, it shows an open file, with handle of zero, as expected.  But
>>> when I do a raw_input(), it gets:
>>>     EOFError: EOF when reading a line
>>>
>>
>> I think the error depends on the specific OS version/service pack. But at
>> least on XP this appears to fix it:
>>
>> http://support.microsoft.com/kb/321788/en-us
>>
>>  Thanks for the link.  Looking at that one, it indicates that Windows 2000
> fixed it in SP4, and XP fixed it in Sp1.  But I'm already running XP SP3, so
> I wonder if it's something new.
>
> Matt, what OS version are you running, and exactly what is happening when
> the error occurs?  (you should be able to figure that out from the stack
> trace)
>
>
> DaveA
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/231ac350/attachment-0001.html>

From davea at ieee.org  Wed Jul  8 11:59:14 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 08 Jul 2009 11:59:14 -0400
Subject: tough-to-explain Python
In-Reply-To: <h3234l$aod$1@reader1.panix.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
Message-ID: <4A54C252.2090304@ieee.org>

kj wrote:
> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5f19 at q11g2000yqi.googlegroups.com> Simon Forman <sajmikins at gmail.com> writes:
>
>   
>> Frankly, I'm of the impression that it's a mistake not to start
>> teaching programming with /the bit/ and work your way up from there.
>> I'm not kidding. I wrote a (draft) article about this: "Computer
>> Curriculum" http://docs.google.com/View?id=dgwr777r_31g4572gp4
>>     
>
>   
>> I really think the only good way to teach computers and programming is
>> to start with a bit, and build up from there. "Ontology recapitulates
>> phylogeny"
>>     
>
>
> I happen to be very receptive to this point of view.  I had the
> benefit of that sort of training (one of the first computer courses
> I took started, believe it or not, with Turing machines, through
> coding in machine language, and compiler theory, and all the way
> up to dabbling with Unix!), and I suspect that the reason it is
> sometimes difficult for me to explain even relatively simple-looking
> things to others is that I have this background that I unconsciously,
> and incorrectly, take for granted in others...  There is this
> persistent idea "out there" that programming is a very accessible
> skill, like cooking or gardening, anyone can do it, and even profit
> from it, monetarily or otherwise, etc., and to some extent I am
> actively contributing to this perception by teaching this course
> to non-programmers (experimental biologists to be more precise),
> but maybe this idea is not entirely true...  Maybe, to get past
> the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest
> that real computer scientists learn about in their formal training...
>
> kj
>
>
>   
And I learned to program Analog Computers, along with APL, in an early 
course.  In my case assembly language came later, but by then we had 
covered the electronics behind transistors, and Karnough maps, logic 
diagrams, and so on.  By the time I graduated, I had five six-level 
languages and two assembly languages under my belt.

.DaveA


From aahz at pythoncraft.com  Wed Jul  8 11:59:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 08:59:19 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
	<h32eoh$ql8$1@reader1.panix.com>
Message-ID: <h32fon$264$1@panix3.panix.com>

In article <h32eoh$ql8$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>OK, so, scratching from my original post the case
>
><identifier>.<identifier> = <expression>
>
>(as being a special case of <identifier> = <expression>), still,
>to the extent that I understand your post, the "=" in
>
>  x = 1
>
>means something fundamentally different (in terms of Python's
>underlying implementation) from the "=" in
>
>  y[0] = 1
>
>No?

No.  ;-)  What's different is not the ``=`` but the construction of the
assignment target before ``=`` gets executed.  Consider also this:

x, y = y, x
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From xahlee at gmail.com  Wed Jul  8 12:19:23 2009
From: xahlee at gmail.com (Xah Lee)
Date: Wed, 8 Jul 2009 09:19:23 -0700 (PDT)
Subject: OT: unix to Windows technology
Message-ID: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>

Dear unixers & lispers,

i've been using Mac for the past 19 years, and been a professional sys
admin or web app developers on the unix platform, since 1998 (maily
Solaris, Apache, Perl, Java, SQL, PHP). In june, i bought a PC (not
for the first time though), and made a switch to Windows, for the
first time, in the sense as a developer instead of just a casual PC
user i've been.

In the past month, i've spend about 5 hours a day digging into MS
Windows tech, in particluar, read over 200 Wikipedia articles in
detail related to Windows technology. (192 of them linked)

Here's a write up of the whole story, my experiences, including some
tech introduction to MS Windows from a sys admin or programer point of
view.

? Switching from Mac/Unix To PC/Windows
  http://xahlee.org/mswin/switch_to_windows.html

Some slightly noteworthy subsections are:

? Removing HP/Compaq Software
  http://xahlee.org/mswin/hp_bundled_apps.html

? Installing Cygwin Tutorial
  http://xahlee.org/mswin/installing_cygwin.html

? Mac and Windows File Conversion
  http://xahlee.org/mswin/mac_windows_file_conv.html

? Unix And Windows File Permission Systems
  http://xahlee.org/mswin/file_perm_systems.html

? Introduction to Windows Scripting
  http://xahlee.org/mswin/windows_scripting.html

Some articles (not shown above) are still work in progress, such as
VBScript tutorial and PowerShell tutorial. Hoping to complete in the
coming months or years.

comment & feedback welcome, esp if you are a Windows expert and answer
some of my unanswered questions on the page.

  Xah
? http://xahlee.org/

?


From james at agentultra.com  Wed Jul  8 12:31:40 2009
From: james at agentultra.com (J Kenneth King)
Date: Wed, 08 Jul 2009 12:31:40 -0400
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
	<mailman.2844.1247065448.8015.python-list@python.org>
Message-ID: <858wizdtlf.fsf@agentultra.com>

Fri?rik M?r J?nsson <fridrik at pyth.net> writes:

> ma wrote:
>> filter(lambda x: x, your_list)
>
> Good call! Equivalent but more efficient:
>
>  filter(None, your_list)
>
> Regards,
> Fri?rik M?r

I was wondering when someone would mention filter()


From robert.kern at gmail.com  Wed Jul  8 12:38:33 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 08 Jul 2009 11:38:33 -0500
Subject: Does cProfile include IO wait time?
In-Reply-To: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>
References: <u5S3m.11107$aX1.5769@nlpi067.nbdc.sbc.com>
Message-ID: <h32i29$iut$1@ger.gmane.org>

On 2009-07-04 19:03, Matthew Wilson wrote:
> I have a command-line script that loads about 100 yaml files.  It takes
> 2 or 3 seconds.  I profiled my code and I'm using pstats to find what is
> the bottleneck.
>
> Here's the top 10 functions, sorted by internal time:
>
>      In [5]: _3.sort_stats('time').print_stats(10)
>      Sat Jul  4 13:25:40 2009    pitz_prof
>
>               756872 function calls (739759 primitive calls) in 8.621 CPU seconds
>
>         Ordered by: internal time
>         List reduced from 1700 to 10 due to restriction<10>
>
>         ncalls  tottime  percall  cumtime  percall filename:lineno(function)
>          15153    0.446    0.000    0.503    0.000 build/bdist.linux-i686/egg/yaml/reader.py:134(forward)
>          30530    0.424    0.000    0.842    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:142(need_more_tokens)
>          98037    0.423    0.000    0.423    0.000 build/bdist.linux-i686/egg/yaml/reader.py:122(peek)
>           1955    0.415    0.000    1.265    0.001 build/bdist.linux-i686/egg/yaml/scanner.py:1275(scan_plain)
>          69935    0.381    0.000    0.381    0.000 {isinstance}
>          18901    0.329    0.000    3.908    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:113(check_token)
>           5414    0.277    0.000    0.794    0.000 /home/matt/projects/pitz/pitz/__init__.py:34(f)
>          30935    0.258    0.000    0.364    0.000 build/bdist.linux-i686/egg/yaml/scanner.py:276(stale_possible_simple_keys)
>          18945    0.192    0.000    0.314    0.000 /usr/local/lib/python2.6/uuid.py:180(__cmp__)
>           2368    0.172    0.000    1.345    0.001 build/bdist.linux-i686/egg/yaml/parser.py:268(parse_node)
>
> I expected to see a bunch of my IO file-reading code in there, but I don't.  So
> this makes me think that the profiler uses CPU time, not
> clock-on-the-wall time.

It should be basically wall-clock time on Linux. The timer function underneath 
is gettimeofday(2). Look in Modules/_lsprof.c of the Python sources for the 
function hpTimer().

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From no.email at please.post  Wed Jul  8 12:38:48 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 16:38:48 +0000 (UTC)
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<0778f257-d36c-4e13-93ea-bf8d448c82e2@b15g2000yqd.googlegroups.com>
	<h32eoh$ql8$1@reader1.panix.com> <h32fon$264$1@panix3.panix.com>
Message-ID: <h32i2o$eop$1@reader1.panix.com>

In <h32fon$264$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:

>In article <h32eoh$ql8$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>
>>OK, so, scratching from my original post the case
>>
>><identifier>.<identifier> = <expression>
>>
>>(as being a special case of <identifier> = <expression>), still,
>>to the extent that I understand your post, the "=" in
>>
>>  x = 1
>>
>>means something fundamentally different (in terms of Python's
>>underlying implementation) from the "=" in
>>
>>  y[0] = 1
>>
>>No?

>No.  ;-)

No???  Just when I thought I finally understood all this!

>What's different is not the ``=`` but the construction of the
>assignment target before ``=`` gets executed.

Hmm.  OK, I went to the link you posted in your other message
(http://docs.python.org/reference/simple_stmts.html#assignment-statements)
and I find this (my emphasis):

    Assignment of an object to a single target is recursively defined as follows.

    * If the target is an identifier (name):

	  o If the name does not occur in a global statement in
	    the current code block: the name is bound to the object
                                    ^^^^^^^^^^^^^^^^^
	    in the current local namespace.

	  o Otherwise: the name is bound to the object in the
                       ^^^^^^^^^^^^^^^^^
	    current global namespace.

      The name is rebound if it was already bound. This may cause
      the reference count for the object previously bound to the
      name to reach zero, causing the object to be deallocated and
      its destructor (if it has one) to be called.

    * If the target is a target list enclosed in parentheses or in
      square brackets... (I'LL IGNORE THIS FOR NOW)

    * If the target is an attribute reference: The primary expression
      in the reference is evaluated. It should yield an object with
      assignable attributes; if this is not the case, TypeError is
      raised. That object is then asked to assign the assigned
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      object to the given attribute; if it cannot perform the
      ^^^^^^
      assignment, it raises an exception (usually but not necessarily
      AttributeError).

    * If the target is a subscription: The primary expression in
      the reference is evaluated. It should yield either a mutable
      sequence object (such as a list) or a mapping object (such
      as a dictionary). Next, the subscript expression is evaluated.

      If the primary is a mutable sequence object (such as a
      list),...  [CONDITIONS ON THE INDEX EXPRESSION OMITTED]...
      the sequence is asked to assign the assigned object to its
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      item with that index....

      If the primary is a mapping object (such as a dictionary),...
      [CONDITIONS ON THE SUBSCRIPT EXPRESSION OMITTED]... the
                                                          ^^^
      mapping is then asked to create a key/datum pair which maps
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      the subscript to the assigned object.
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    * If the target is a slicing: [INDEX STUFF OMITTED]... the
                                                           ^^^
      sequence object is asked to replace the slice with the items
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      of the assigned sequence...
      ^^^^^^^^^^^^^^^^^^^^^^^^

OK, I originally interpreted what Lundh wrote in his two articles
that the "binding" described at the very beginning (i.e. when the
target is an identifier), which I take to make an entry or modify
such an entry in a namespace, is a *categorically different*
operation from the remaining operations underlined above.

I interpreted Paul Boddie's correction in his response to me as
saying that the "assignment" mentioned for the case when the target
is an attribute reference is actually a special case of the
"assignment" to simple identifiers (i.e. it also means "binding").

But that still leaves all the other "assignments" (or the like)
underlined above.  I don't think that the full definitions of these
remaining cases are covered by the same rule, even though the rule
is described as "recursive."  I think that the writer has something
else in mind, and in particular, something *other* than binding,
but the author remains vague on exactly what this means.

Clearly, both Lundh and the documentation draw some distinction
between "binding" and some other forms of "assignment" (which remain
ill-defined throughout).  This distinction is what I was referring
to when I said that "=" means different things in different contexts.

kj


From fridrik at pyth.net  Wed Jul  8 12:44:47 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Wed, 8 Jul 2009 16:44:47 +0000
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <858wizdtlf.fsf@agentultra.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<148918f0907080754i31e8b2e5i4132a51f94d204e1@mail.gmail.com>
	<mailman.2844.1247065448.8015.python-list@python.org>
	<858wizdtlf.fsf@agentultra.com>
Message-ID: <7D21C328-8320-4DF8-9E8B-08093441D270@pyth.net>

J Kenneth King wrote:
> I was wondering when someone would mention filter()

I was happy to see that too.

It's clean, faster than list comprehension and in terms of clarity  
it's only to be expected that the developer is familiar with, or at  
least willing to look up, the available built-in methods.

Regards,
Fri?rik M?r

From kentilton at gmail.com  Wed Jul  8 12:51:57 2009
From: kentilton at gmail.com (Kenneth Tilton)
Date: Wed, 08 Jul 2009 12:51:57 -0400
Subject: OT: unix to Windows technology
In-Reply-To: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
References: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
Message-ID: <4a54ceb0$0$5898$607ed4bc@cv.net>

Xah Lee wrote:
> Dear unixers & lispers,
> 
> i've been using Mac for the past 19 years, and been a professional sys
> admin or web app developers on the unix platform, since 1998 (maily
> Solaris, Apache, Perl, Java, SQL, PHP). In june, i bought a PC (not
> for the first time though), and made a switch to Windows, for the
> first time, in the sense as a developer instead of just a casual PC
> user i've been.
> 
> In the past month, i've spend about 5 hours a day digging into MS
> Windows tech, in particluar, read over 200 Wikipedia articles in
> detail related to Windows technology. (192 of them linked)
> 
> Here's a write up of the whole story, my experiences, including some
> tech introduction to MS Windows from a sys admin or programer point of
> view.
> 
> ? Switching from Mac/Unix To PC/Windows
>   http://xahlee.org/mswin/switch_to_windows.html
> 
> Some slightly noteworthy subsections are:
> 
> ? Removing HP/Compaq Software
>   http://xahlee.org/mswin/hp_bundled_apps.html
> 
> ? Installing Cygwin Tutorial
>   http://xahlee.org/mswin/installing_cygwin.html
> 
> ? Mac and Windows File Conversion
>   http://xahlee.org/mswin/mac_windows_file_conv.html
> 
> ? Unix And Windows File Permission Systems
>   http://xahlee.org/mswin/file_perm_systems.html
> 
> ? Introduction to Windows Scripting
>   http://xahlee.org/mswin/windows_scripting.html
> 
> Some articles (not shown above) are still work in progress, such as
> VBScript tutorial and PowerShell tutorial. Hoping to complete in the
> coming months or years.
> 
> comment & feedback welcome, esp if you are a Windows expert and answer
> some of my unanswered questions on the page.
> 
>   Xah
> ? http://xahlee.org/
> 
> ?

You just discovered PCs are cheaper?

The funny thing is that that is Microsoft's answer to the Apple Mac-PC 
ads, they show people shopping for computers and just comparing hardware 
and price as if this is some kind of breakthrough. But I understand: 
they have no answer to Windows being such a nightmare and the Mac being 
such a joy.

kt


From tjreedy at udel.edu  Wed Jul  8 12:57:31 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 08 Jul 2009 12:57:31 -0400
Subject: The meaning of "=" (Was: tough-to-explain Python)
In-Reply-To: <h3291j$mfu$1@reader1.panix.com>
References: <h3291j$mfu$1@reader1.panix.com>
Message-ID: <h32j5r$mn7$1@ger.gmane.org>

kj wrote:

> To clarify, this comes from my reading of Fredrik Lundh's pages
> "Python Objects" (http://effbot.org/zone/python-objects.htm) and
> "Call By Object" (http://effbot.org/zone/call-by-object.htm).
[snip]
> [END OF LENGTHY QUOTE]
> 
> Therefore, extending just a bit beyond Lundh's explanation, if we
> did:
> 
> name = []
> name.append(1)
> name[0] = 3
> 
> ...the second assignment would amount to a method call on the object
> called 'name', an operation of a very different nature (according
> to Lundh) from the first assignment, which is a modification of a
> namespace.

I disagree. Assignment creates an association. Modification of a 
namespace, when implemented, amounts to a method call on the concrete 
object, whether a Python object or not, that implements the abstraction 
of a namespace. At module scope,
   name = ob
is the same as
   globals()['name']=ob
Within a class statement, substitute '<class-dict>' for 'globals'
Within functions, CPython uses an internal array, so
   name = ob
becomes
   <locals_array>[name-number] = ob

Or, to put it another way, Python dicts and lists are, considered 
abstractly, associations also, just like namespaces. Dicts are more 
general than namespaces, sequences are 'number-spaces' instead of 
name-spaces.

Terry Jan Reedy



From nobody at nowhere.com  Wed Jul  8 13:03:35 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 08 Jul 2009 18:03:35 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
	<6xB4m.21104$vi5.8567@uutiset.elisa.fi>
	<pan.2009.07.07.22.37.43.422000@nowhere.com>
	<mailman.2818.1247033106.8015.python-list@python.org>
Message-ID: <pan.2009.07.08.17.03.35.547000@nowhere.com>

On Tue, 07 Jul 2009 22:49:22 -0700, Dennis Lee Bieber wrote:

> On Tue, 07 Jul 2009 23:37:43 +0100, Nobody <nobody at nowhere.com>
> declaimed the following in gmane.comp.python.general:
> 
>> AFAIK, the only real difference between "USB-1 conformant" and "USB-2
>> conformant" is that the latter actually passed a test of its ability to
>> say "no, I can't do high-speed", while the former didn't. The check for
>> high-speed capability was designed such that it shouldn't cause problems
>> for USB-1 devices, but individual USB-1 devices weren't actually tested
>> for this.
> 
> 	USB-1 or USB-1.1? As I recall the latter is capable of 11Mbps
> whereas the original USB spec was much lower... (of course, USB 2 at top
> is 480Mbps)

USB 1.0 supports 1.5Mbps (low-speed) and 12MBps (full-speed). Hosts and
hubs must support both, functions (devices) can use either. USB 1.1 was
a bug-fix release which solved some interoperability issues arising from
ambiguities in the USB 1.0 standard.



From lucas_junqueira at yahoo.com  Wed Jul  8 13:07:33 2009
From: lucas_junqueira at yahoo.com (Lucas Junqueira)
Date: Wed, 8 Jul 2009 10:07:33 -0700 (PDT)
Subject: windows command-line
Message-ID: <376017.28322.qm@web30601.mail.mud.yahoo.com>

Hi, I'd like to run a simple windows command-line program from within my python script and agt all the returt it generates. Is this possible? How can I do it?

Thank you!



      ____________________________________________________________________________________
Veja quais s?o os assuntos do momento no Yahoo! +Buscados
http://br.maisbuscados.yahoo.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/823cbd83/attachment-0001.html>

From cameron.pulsford at gmail.com  Wed Jul  8 13:09:43 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Wed, 8 Jul 2009 13:09:43 -0400
Subject: Problem with list of dicts and copying
Message-ID: <5700df6b0907081009p5ec4167cqec36e915e0f6c4@mail.gmail.com>

Hello all, I'm redoing a sudoku solver of mine and I ran into an issue with
lists of dicts. Bear with me for a second before I get to the actual
problem... I'm representing the board as a dictionary, where the keys are
(x, y) positions, and the values are candidates. So my program goes along
picking numbers from the list of candidates and then propagating the
constraints. So it might place a 6, which would then remove 6 as a candidate
from that row column and grid. However, that might leave a spot with no
candidates, which means we placed a legal but not correct number. This is
where my problem arises. I keep a running list of the boards which is
updated every time I find a legal number that doesn't invalidate the boards.
I add onto this list by doing "boards.append(self.board.copy())". When I
place a legal but invalid number I do "self.board = boards[-1].copy()" to
return the board to the last known good state. And when I completely exhaust
the candidates for a spot and must backtrack to a different spot (instead of
simply trying a different candidate of the current spot) I do "self.board =
boards[-1].copy() and then del boards[-1]"
Basically my boards list should be copies of good boards, and when I need to
refresh the current board, I want to pull off a copy of the correct one.
Essentially (after watching the debugging output) it looks like this isn't
happening. I am always modifying the same board. The algo follows, and I can
post the rest of the code if necessary. So am I using the dict.copy() wrong?
Am I guessing I have a tricky problem with the "=" in "self.board =
boards[-1].copy()"

    def solve(self):
        previousValue = dict((blank, 0) for blank in self.blanks())
        self.fillInCandidates()
        continuing, boards, guesses = False, [self.board.copy()], 0
        while len(self.blanks()) > 0:
            if continuing == False:
                cp = self.mrv()
            continuing = False
            nl = self.nextLegal(cp, previousValue[cp])
            previousValue[cp] = nl
            if nl != 0:
                self.board[cp] = nl
                guesses += 1
                self.update(nl, cp[0], cp[1])
                if self.isNotLegal():
                    continuing = True
                    self.board = boards[-1].copy()
                else:
                    boards.append(self.board.copy())
            else:
                previousValue[cp] = 0
                self.board = boards[-1].copy()
                del boards[-1]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090708/18d7843a/attachment-0001.html>

From nobody at nowhere.com  Wed Jul  8 13:19:16 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 08 Jul 2009 18:19:16 +0100
Subject: Python and webcam capture delay?
References: <dC34m.20648$vi5.6555@uutiset.elisa.fi>
	<lfh25518jrbmpt9ccp1t7phgrig2lcfv3q@4ax.com>
	<czg4m.20786$vi5.9666@uutiset.elisa.fi>
	<mailman.2698.1246893772.8015.python-list@python.org>
	<RGq4m.20945$vi5.15615@uutiset.elisa.fi>
	<pan.2009.07.06.19.41.52.828000@nowhere.com>
	<0ca855t29jklb0o0gi31ourfk3lstdiepf@4ax.com>
Message-ID: <pan.2009.07.08.17.19.16.640000@nowhere.com>

On Tue, 07 Jul 2009 22:11:12 -0700, Tim Roberts wrote:

>>The webcam is bound to do some encoding; most of them use USB "full speed"
>>(12Mbit/sec), which isn't enough for raw 640x480x24bpp at 30fps data.
> 
> That's not true.  Most of the web cams made in the last 5 years or so run
> at high speed, 480 Mbps.  Full speed only gets you 1 fps at 640x480
> uncompressed, so it's really only useful for the most primitive video
> conference cams.

The very earliest models typically only did 320x200, while later USB-1
webcams used onboard compression to get a decent framerate.

For internet use, 12Mbps isn't that much of an obstacle; the internet
connection's upload speed is more likely to be the limiting factor. Faster
speeds are more useful for things like LAN-based CCTV systems.



From emile at fenx.com  Wed Jul  8 13:23:54 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 08 Jul 2009 10:23:54 -0700
Subject: windows command-line
In-Reply-To: <376017.28322.qm@web30601.mail.mud.yahoo.com>
References: <376017.28322.qm@web30601.mail.mud.yahoo.com>
Message-ID: <h32kne$s0l$1@ger.gmane.org>

On 7/8/2009 10:07 AM Lucas Junqueira said...
> Hi, I'd like to run a simple windows command-line program from within my 
> python script and agt all the returt it generates. Is this possible? How 
> can I do it?

Depending on python version, look into subprocess, commands or os.pipe 
and related.

Emile



From nobody at nowhere.com  Wed Jul  8 13:25:49 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 08 Jul 2009 18:25:49 +0100
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
Message-ID: <pan.2009.07.08.17.25.49.219000@nowhere.com>

On Tue, 07 Jul 2009 21:31:12 -0700, Rajat wrote:

>> > By the way most operating systems don't lock a file when it's opened for
>> > reading or writing or even executed.
>>
>> The general conclusion seems to be that mandatory locking is more trouble
>> than it's worth.
> 
> My OS is a windows XP sp3. All I'm trying to achieve is to close an
> application ( which could be a notepad, a wordpad or some other text
> editor) that have opened my file. Once the file is closed I can easily
> delete that file.
> 
> I guess, if file is opened by one of that application, the file must
> be locked and so is the reason I cannot delete the file.

Windows doesn't allow you to delete (or rename) open files. It's up to the
application as to whether it keeps the file open or closes it once it has
been read.

> Please suggest if this is fine.

If you can't delete the file, then you can't delete it. You shouldn't be
trying to kill off applications so that you can delete the file. Just do
what other Windows programs (including those which are part of Windows)
do: display a dialog telling the user to close the application then try
again.



From xahlee at gmail.com  Wed Jul  8 13:34:50 2009
From: xahlee at gmail.com (Xah Lee)
Date: Wed, 8 Jul 2009 10:34:50 -0700 (PDT)
Subject: OT: unix to Windows technology
References: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
	<4a54ceb0$0$5898$607ed4bc@cv.net>
Message-ID: <16430ee7-888e-42ef-9c84-14df4b78ee04@p36g2000prn.googlegroups.com>

Xah Lee wrote:
> ? Switching from Mac/Unix To PC/Windows
>  http://xahlee.org/mswin/switch_to_windows.html

Kenneth Tilton wrote:
> You just discovered PCs are cheaper?
>
> The funny thing is that that is Microsoft's answer to the Apple Mac-PC
> ads, they show people shopping for computers and just comparing hardware
> and price as if this is some kind of breakthrough. But I understand:
> they have no answer to Windows being such a nightmare and the Mac being
> such a joy.

well, i've been owning Macs for over the past 19 years. From a
dedicated fan thru-out the 1990s, to still fan in early of 2000s with
debut of OS X.

Mac prices in comparison to PC has gone up and downs. In the early
1990s for example, it is maybe 4 times more. Lowest is probably in the
mid 1990s, where 3rd party companies are licensed to producing clones,
and that happens to also be a period that Mac OS is the worst,
crashing few times per day, similar to Win 95 and 98. I think in the
early 2000s the price gap came closer, and since maybe 2005 it start
to increase again.

for someone like me, i've read all the pros and cons of Mac vs PC.
I've read, for instance, basically all MacWorld and MacUser mags in
the early 1990s until they become defunct. (and often MacWeek too) Not
to mention the huge amount of websites, especially in the late 1990s
where there are a number of high profile dedicated mac fan sites. I
also have often attended the yearly Mac World Expo, eagerly antipating
Steve Job's ?O, one more thing...?  etc... and etc and etc. As a
hyperbole, i've prob read more Mac vs PC argument from newsgroup users
combined. LOL

as to the price comparison... a better metric is value/price ratio. I
think, over the past 20 years, the value/price ratio of Mac compared
to PC, namely:

(MacValue/MacPrice)/(PC_value/PC_price)

is going down, starting with Windows NT 4, and going downhill quickly
with Windows XP, and Vista, .NET.

as far as SOFTWARE technology goes, Apple's falling lamer and lamer
from its 1990s mountain top of lisps and hypercards and desktop
publishing stuff. Microsoft Windows, starting from MS-DOS moronicity,
today, with its .NET, F#, PowerShell, is quite beyond Apple's
perpetual diddling with its prettification of OS X.

  Xah
? http://xahlee.org/

?


From paul.lafollette at gmail.com  Wed Jul  8 13:35:44 2009
From: paul.lafollette at gmail.com (Paul LaFollette)
Date: Wed, 8 Jul 2009 13:35:44 -0400
Subject: function local namespace question
Message-ID: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>

Kind people,

Using Python 3.1 under FreeBSD and WinXP.

I've been tearing my hair out trying to solve this myself, but I need
to ask for help.   I want (for obscure reasons) to be able to log
transactions in the namespace(s) of a script.  Specifically I would
like to log creation of identifiers, changes in the binding of
identifiers ("assignment") and lookups.  This turns out to be pretty
easy in the global and local namespaces... I simply subclass dict,
override the appropriate operations to include the logging operations
I want, and then exec the code using my dictionaries as the global and
local namespaces.  All  of this  works just dandy until I try to
extend it to functions.

I cannot figure out any way to get a hook into the local namespace of
a user defined function.  I have tried making a wrapper class that
grabs the function call and then uses exec to invoke
myfunction.__code__ with my own dictionaries.  This runs the (no
argument) function properly (losing the return value, but I can deal
with that) but never accesses the local logging dictionary that I
specify in the exec() call. Perhaps the local namespace of a function
is not a dict at all?

Anyway, is there any way (however clumsy) to do what I want to do?
Thank you for your help.
Paul

---------------------------
Paul LaFollette
CIS Department
Temple University
paul.lafollette(at)temple.edu
www.cis.temple.edu/~lafollet


From Lacrima.Maxim at gmail.com  Wed Jul  8 13:52:44 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Wed, 8 Jul 2009 10:52:44 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
Message-ID: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>

Hello!

I have just started using Emacs to write python scripts.
I installed python-mode.el

Then I just tried this code:

print 'hello world'

When I press C-c RET, new blank window is opened and emacs says:
(Shell command succeeded with no output)
So where is my 'hello world'?

When I do C-c C-c, it prints 'hello world' successfully.
Why in the first case I get no output?

Thanks in advance!

With regards, Max
(sorry if my English isn't very proper)


From sajmikins at gmail.com  Wed Jul  8 14:01:28 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Wed, 8 Jul 2009 11:01:28 -0700 (PDT)
Subject: ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <d9f7e0f1-3069-4d93-9839-1c7828a774b5@y17g2000yqn.googlegroups.com>

On Jul 8, 10:44?am, Daniel Austria <futureb... at gmx.at> wrote:
> Hi python - hackers,
>
> just one question. How can i remove all 0 values in a list? Sure - i
> can loop over it, but that s not a neat style. ?list.remove() will
> only remove the first occurence. Doing that while no exception is
> raised is also uncool, right?
>
> Some suggestions?
>
> Best,
> Dan

If you are doing something like this:

L = [0, 0, 0, 1, 1, 1, 0]
removeZeros(L)
number_of_ones = len(L)

you can just use sum() like so:

number_of_ones = sum(L)



HTH


From no.email at please.post  Wed Jul  8 14:10:08 2009
From: no.email at please.post (kj)
Date: Wed, 8 Jul 2009 18:10:08 +0000 (UTC)
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com> <m2r5wsb55n.fsf@cs.uu.nl>
Message-ID: <h32ne0$9l4$1@reader1.panix.com>

In <m2r5wsb55n.fsf at cs.uu.nl> Piet van Oostrum <piet at cs.uu.nl> writes:

>>>>>> kj <no.email at please.post> (kj) wrote:

>>kj> Does anyone know where I can buy the Python library reference in
>>kj> printed form?  (I'd rather not print the whole 1200+-page tome
>>kj> myself.)  I'm interested in both/either 2.6 and 3.0.

>Maybe you can have a copy printed at lulu.com.

Interesting idea...  Doesn't look like they offer such service.

>It would even be nicer if
>the PSF would offer them at lulu.

That would be great.

kj



From http  Wed Jul  8 14:43:19 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 11:43:19 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
Message-ID: <7xiqi3dni0.fsf@ruckus.brouhaha.com>

Bearophile <bearophileHUGS at lycos.com> writes:
> > ? ? print x, len(tuple(g))
> 
> Avoid that len(tuple(g)), use something like the following

print x, sum(1 for _ in g)


From http  Wed Jul  8 14:49:52 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 11:49:52 -0700
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
Message-ID: <7xd48bdn73.fsf@ruckus.brouhaha.com>

Daniel Austria <futurebase at gmx.at> writes:
> just one question. How can i remove all 0 values in a list? 

I prefer:

   newlist = list(x for x in oldlist if x != 0)

to the square bracket list comprehension that a few people have
suggested.  This is because in python 2.x, the listcomp "leaks" its
index variable into the surrounding scope, but the generator
expression above doesn't.  Usually not a big deal, but an extra bit of
hygiene never(?) hurts.


From fetchinson at googlemail.com  Wed Jul  8 14:56:39 2009
From: fetchinson at googlemail.com (Daniel Fetchinson)
Date: Wed, 8 Jul 2009 11:56:39 -0700
Subject: A Bug By Any Other Name ...
In-Reply-To: <h31c14$k6m$4@ger.gmane.org>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<fbe2e2100907061948g37c4ce0fwcdea79b91b3c342@mail.gmail.com>
	<h2ujrs$4c0$1@ger.gmane.org>
	<mailman.2754.1246945937.8015.python-list@python.org>
	<4a531560$0$9355$426a74cc@news.free.fr>
	<fbe2e2100907070923n3caee67am2823d3b92209d6e4@mail.gmail.com>
	<h31c14$k6m$4@ger.gmane.org>
Message-ID: <fbe2e2100907081156t140246eemed6c68de6ead140d@mail.gmail.com>

>> But this academic discussion is honestly a little pointless. The OP
>> was referring to a expectation, coming from C, that is not fulfilled
>> in python. What's wrong with mentioning it somewhere for the sake of
>> helping C programmers?
>>
> 	And where does one stop? After all, my primary work language at the
> time I first encountered Python was FORTRAN77; and my home system at the
> time was an Amiga with ARexx... (granted, I did have a C compiler on it
> -- which I do not have on this WinXP machine)... And programming, even
> in C, on the Amiga still inflicted BCPL concepts upon one ("AmigaDOS",
> the "user" view, was a port of Tripos user view on top of the Amiga
> executive libraries).
>
> 	Do we mention how Python differs from F77, F90, Ada, Rexx, LISP,
> RPG, APL, Pascal, BASIC, and COBOL (I've done all except RPG since
> graduating high school).
>
> 	In my mind... Anyone whose only experience with programming language
> concepts is C/C++ deserves the shock of finding that other languages ARE
> DIFFERENT! Even if they never use other languages they should at least
> have been exposed to language design options and rationales...
>
> 	Okay, I don't know what current curricula consist of, but in the
> late 70s, a CS degree at my college required two sessions of FORTRAN,
> two of COBOL, Assembly (numerically, it followed advanced FORTRAN),
> database (followed COBOL)... and then diverged into Business Programming
> vs Systems Programming (Business required lots of accounting/statistics
> courses [stat-II was SPSS], Systems was operating system and language
> design). Electives included BASIC, Pascal, APL (The professor for the
> data structures course made the mistake of once allowing an assignment
> -- hashed head multiple-linked list -- to be done in any language he
> could read <G>; I did it in a BASIC that only supported 4 open files at
> a time... I think someone did it in SNOBOL)
>
> 	C wasn't available on the XEROX Sigma-7; I did have a first edition
> K&R. By graduation I'd also been exposed to the initial Ada
> reference/rational (a working compiler -- Ada/Ed -- didn't come out
> until after I'd graduated).


Okay, so where does one stop? I'd say C deserves special treatment as
opposed to all the other languages you mentioned because Guido himself
admits to influences from C (and ABC but I hope you won't assume that
ABC is a widely used language).

Maybe you didn't read these messages from me in this thread:

By the way, assignments in conditionals. Guido explicitly referred to
C when he forbade assignment in conditionals, citing common
typos/errors in C code such as if( x = 5 ){ .... } instead of if( x ==
5 ){ ..... }. So even he realized that warning people about different
usage in python and C is a good thing. Expectations from C work
sometimes, and sometimes they don't. In latter case a little warning
is useful.

And also,

Seriously, ask Guido about the influence of C vs. fortran (or cobol,
ada, pascal, etc). Somewhere you can find him quoted as saying that
python was originally intended to "bridge the gap between the shell
and C". I've never heard him talk about fortran (or cobol, ada,
pascal, etc).

So don't get me wrong, I'm sufficiently impressed by your knowledge of
various computer languages, I admit to only knowing C and basic and
some fortran (and of course python :)), but if Guido himself thinks
the influence of C on python is more important than the others, then
let's not doubt him.

And yes, I shamelessly admit to arguing based on a higher authority
and not based on merit, but in this case it's appropriate, I think :)

Cheers,
Daniel


-- 
Psss, psss, put it down! - http://www.cafepress.com/putitdown


From backup95 at netcabo.pt  Wed Jul  8 15:32:36 2009
From: backup95 at netcabo.pt (=?ISO-8859-1?Q?Jo=E3o_Valverde?=)
Date: Wed, 08 Jul 2009 20:32:36 +0100
Subject: ISO library ref in printed form
In-Reply-To: <h2vcp9$66b$1@reader1.panix.com>
References: <h2vcp9$66b$1@reader1.panix.com>
Message-ID: <4A54F454.9060007@netcabo.pt>

kj wrote:
> Does anyone know where I can buy the Python library reference in
> printed form?  (I'd rather not print the whole 1200+-page tome
> myself.)  I'm interested in both/either 2.6 and 3.0.
>
> TIA!
>
> kj
>   
Why not download the documentation, take it to a local copy shop and 
have it printed and bound there?

http://docs.python.org/download.html
http://docs.python.org/3.1/download.html


From aahz at pythoncraft.com  Wed Jul  8 15:33:57 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 12:33:57 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
Message-ID: <h32sb5$eoq$1@panix3.panix.com>

In article <050094ea-faf4-4e03-875d-9c2c63090a89 at y17g2000yqn.googlegroups.com>,
Bearophile  <bearophileHUGS at lycos.com> wrote:
>Vilya Harvey:
>>
>> from itertools import groupby
>> for x, g in groupby([fields[1] for fields in data]):
>> =A0 =A0 print x, len(tuple(g))
>
>Avoid that len(tuple(g)), use something like the following, it's lazy
>and saves some memory.

The question is whether it saves time, have you tested it?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From piet at cs.uu.nl  Wed Jul  8 15:54:23 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 21:54:23 +0200
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
Message-ID: <m21vorar2o.fsf@cs.uu.nl>

>>>>> Lacrima <Lacrima.Maxim at gmail.com> (L) wrote:

>L> Hello!
>L> I have just started using Emacs to write python scripts.
>L> I installed python-mode.el

>L> Then I just tried this code:

>L> print 'hello world'

>L> When I press C-c RET, new blank window is opened and emacs says:
>L> (Shell command succeeded with no output)
>L> So where is my 'hello world'?

>L> When I do C-c C-c, it prints 'hello world' successfully.
>L> Why in the first case I get no output?

Can you check in the buffer where you have the python code what command
C-c RET is bound to?
With C-h k C-c RET

Shell command succeeded with no output suggests that is has a different
binding than the standard one in python-mode.

Did you happen to name your file 'test' or 'test.py?

C-c RET does an import and 'import test' imports a standard module test.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul  8 15:56:01 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 08 Jul 2009 21:56:01 +0200
Subject: ISO library ref in printed form
References: <h2vcp9$66b$1@reader1.panix.com> <m2r5wsb55n.fsf@cs.uu.nl>
	<h32ne0$9l4$1@reader1.panix.com>
Message-ID: <m2ws6j9cfi.fsf@cs.uu.nl>

>>>>> kj <no.email at please.post> (k) wrote:

>k> In <m2r5wsb55n.fsf at cs.uu.nl> Piet van Oostrum <piet at cs.uu.nl> writes:
>>>>>>>> kj <no.email at please.post> (kj) wrote:

>kj> Does anyone know where I can buy the Python library reference in
>kj> printed form?  (I'd rather not print the whole 1200+-page tome
>kj> myself.)  I'm interested in both/either 2.6 and 3.0.

>>> Maybe you can have a copy printed at lulu.com.

>k> Interesting idea...  Doesn't look like they offer such service.

You can upload your own PDF file and have them print a single copy. You
would have to split the file yourself in manageble pieces (< 600
something pages)

>>> It would even be nicer if
>>> the PSF would offer them at lulu.

>k> That would be great.

>k> kj


-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From milesck at umich.edu  Wed Jul  8 16:50:44 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 8 Jul 2009 16:50:44 -0400
Subject: function local namespace question
In-Reply-To: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
References: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
Message-ID: <BFCC62EC-32DF-4E0E-B9E9-DD99D2262F1C@umich.edu>

On Jul 8, 2009, at 1:35 PM, Paul LaFollette wrote:

> I cannot figure out any way to get a hook into the local namespace of
> a user defined function.  I have tried making a wrapper class that
> grabs the function call and then uses exec to invoke
> myfunction.__code__ with my own dictionaries.  This runs the (no
> argument) function properly (losing the return value, but I can deal
> with that) but never accesses the local logging dictionary that I
> specify in the exec() call. Perhaps the local namespace of a function
> is not a dict at all?

Right.  Within functions, local variable name accesses and assignments  
are compiled into bytecode instructions (LOAD_FAST, STORE_FAST) that  
manipulate pointers to objects by indexing directly into a C array in  
the frame.  The "locals" dictionary of a frame is generated on-demand  
from that array when accessed.  There is no way that I'm aware of to  
directly hook into function namespace access and manipulation.

-Miles



From http  Wed Jul  8 17:45:53 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 14:45:53 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>
Message-ID: <7xbpnuzw4u.fsf@ruckus.brouhaha.com>

aahz at pythoncraft.com (Aahz) writes:
> >Avoid that len(tuple(g)), use something like the following, it's lazy
> >and saves some memory.
> The question is whether it saves time, have you tested it?

len(tuple(xrange(100000000))) ... hmm.


From david.bramer at googlemail.com  Wed Jul  8 18:06:22 2009
From: david.bramer at googlemail.com (David)
Date: Wed, 8 Jul 2009 15:06:22 -0700 (PDT)
Subject: regex help
Message-ID: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>

Hi

I have a few regexs I need to do, but im struggling to come up with a
nice way of doing them, and more than anything am here to learn some
tricks and some neat code rather than getting an answer - although
thats obviously what i would like to get to.

Problem 1 -

<span class="chg"
                id="ref_678774_cp">(25.47%)</span><br>

I want to extract 25.47 from here - so far I've tried -

xPer = re.search('<span class="chg" id="ref_"'+str(xID.group(1))+'"_cp
\">(.*?)%', content)

and

xPer = re.search('<span class=\"chg\" id=\"ref_"+str(xID.group(1))+"_cp
\">\((\d*)%\)</span><br>', content)

neither of these seem to do what I want - am I not doing this
correctly? (obviously!)

Problem 2 -

<td>&nbsp;</td>

<td width="1%" class=key>Open:
</td>
<td width="1%" class=val>5.50
</td>
<td>&nbsp;</td>
<td width="1%" class=key>Mkt Cap:
</td>
<td width="1%" class=val>6.92M
</td>
<td>&nbsp;</td>
<td width="1%" class=key>P/E:
</td>
<td width="1%" class=val>21.99
</td>


I want to extract the open, mkt cap and P/E values - but apart from
doing loads of indivdual REs which I think would look messy, I can't
think of a better and neater looking way. Any ideas?

Cheers

David



From aahz at pythoncraft.com  Wed Jul  8 18:22:19 2009
From: aahz at pythoncraft.com (Aahz)
Date: 8 Jul 2009 15:22:19 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>
	<7xbpnuzw4u.fsf@ruckus.brouhaha.com>
Message-ID: <h3366r$du7$1@panix3.panix.com>

In article <7xbpnuzw4u.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>aahz at pythoncraft.com (Aahz) writes:
>>Paul Rubin deleted an attribution:
>>>
>>>Avoid that len(tuple(g)), use something like the following, it's lazy
>>>and saves some memory.
>>
>> The question is whether it saves time, have you tested it?
>
>len(tuple(xrange(100000000))) ... hmm.

When dealing with small N, O() can get easily swamped by the constant
factors.  How often do you deal with more than a hundred fields?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From digitig at gmail.com  Wed Jul  8 18:25:21 2009
From: digitig at gmail.com (Tim Rowe)
Date: Wed, 8 Jul 2009 23:25:21 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006e7ce0$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<006e7ce0$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <aee48b3c0907081525u72320104hd88af95036e545f1@mail.gmail.com>

2009/7/7 Steven D'Aprano <steve at remove-this-cybersource.com.au>:

> Maybe the reason for "so much buggy software" is that people
> inappropriately use assert, thus changing the behaviour of code depending
> on whether it is run with the -O flag or not.

I've done my share of code review and process audits, and assertions
seem *far* to rare for that distinction.

> I don't know what "hostility" you're seeing. The only hostility I'm
> seeing is from the OP, which is bizarre considering that he asked for
> advice and we gave it. What I see is a bunch of people concerned that the
> OP is teaching novices a bad habit, namely, using assert for error
> checking. He claims -- angrily and over and over again -- that in his
> code, the assertions should never fail. Great. Good for him for knowing
> when to use assert. But are the novices going to learn that lesson, or
> will they simply learn "use assert for error checking"?

They are rather more likely to learn if they are taught, aren't they?
Or do you think it's better to keep them in the dark? "There are these
things called assertions -- work them out for yourselves".

I am convinced that the time to teach programmers to consider under
what circumstances a routine can be called and who is responsible for
ensuring that those conditions are met is as soon as they hit the
concept of calling routines. And assertions provide an excellent way
of doing that, fostering good habits for the rest of their careers.
Any hostility from the OP seems to be a response to the persistent
refusal to accept his assurances that he is not using the assertions
for run-time error checking, nor teaching the students to do that,
-- 
Tim Rowe


From http  Wed Jul  8 18:28:17 2009
From: http (Paul Rubin)
Date: 08 Jul 2009 15:28:17 -0700
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>
	<7xbpnuzw4u.fsf@ruckus.brouhaha.com>
	<h3366r$du7$1@panix3.panix.com>
Message-ID: <7xvdm2n726.fsf@ruckus.brouhaha.com>

aahz at pythoncraft.com (Aahz) writes:
> When dealing with small N, O() can get easily swamped by the constant
> factors.  How often do you deal with more than a hundred fields?

The number of fields in the OP's post was not stated.  Expecting it to
be less than 100 seems like an ill-advised presumption.  If N is
unknown, speed-tuning the case where N is small at the expense of
consuming monstrous amounts of memory when N is large sounds 
somewhere between a premature optimization and a nasty bug.



From clp2 at rebertia.com  Wed Jul  8 18:37:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 8 Jul 2009 15:37:48 -0700
Subject: regex help
In-Reply-To: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
Message-ID: <50697b2c0907081537v44c45510kf8e9f143e2213a0@mail.gmail.com>

On Wed, Jul 8, 2009 at 3:06 PM, David<david.bramer at googlemail.com> wrote:
> Hi
>
> I have a few regexs I need to do, but im struggling to come up with a
> nice way of doing them, and more than anything am here to learn some
> tricks and some neat code rather than getting an answer - although
> thats obviously what i would like to get to.
>
> Problem 1 -
>
> <span class="chg"
> ? ? ? ? ? ? ? ?id="ref_678774_cp">(25.47%)</span><br>
>
> I want to extract 25.47 from here - so far I've tried -
>
> xPer = re.search('<span class="chg" id="ref_"'+str(xID.group(1))+'"_cp
> \">(.*?)%', content)
>
> and
>
> xPer = re.search('<span class=\"chg\" id=\"ref_"+str(xID.group(1))+"_cp
> \">\((\d*)%\)</span><br>', content)
>
> neither of these seem to do what I want - am I not doing this
> correctly? (obviously!)
>
> Problem 2 -
>
> <td>&nbsp;</td>
>
> <td width="1%" class=key>Open:
> </td>
> <td width="1%" class=val>5.50
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>Mkt Cap:
> </td>
> <td width="1%" class=val>6.92M
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>P/E:
> </td>
> <td width="1%" class=val>21.99
> </td>
>
>
> I want to extract the open, mkt cap and P/E values - but apart from
> doing loads of indivdual REs which I think would look messy, I can't
> think of a better and neater looking way. Any ideas?

Use an actual HTML parser? Like BeautifulSoup
(http://www.crummy.com/software/BeautifulSoup/), for instance.

I will never understand why so many people try to parse/scrape
HTML/XML with regexes...

Cheers,
Chris
-- 
http://blog.rebertia.com


From usernet at ilthio.net  Wed Jul  8 18:43:41 2009
From: usernet at ilthio.net (Tim Harig)
Date: Wed, 08 Jul 2009 22:43:41 GMT
Subject: regex help
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
	<mailman.2860.1247092671.8015.python-list@python.org>
Message-ID: <xi95m.3641$vO4.3538@flpi145.ffdc.sbc.com>

On 2009-07-08, Chris Rebert <clp2 at rebertia.com> wrote:
> On Wed, Jul 8, 2009 at 3:06 PM, David<david.bramer at googlemail.com> wrote:
>> I want to extract the open, mkt cap and P/E values - but apart from
>> doing loads of indivdual REs which I think would look messy, I can't
>> think of a better and neater looking way. Any ideas?

You are downloading market data?  Yahoo offers its stats in CSV format that
is easier to parse without a dedicated parser.

> Use an actual HTML parser? Like BeautifulSoup
> (http://www.crummy.com/software/BeautifulSoup/), for instance.

I agree with your sentiment exactly.  If the regex he is trying to get is
difficult enough that he has to ask; then, yes, he should be using a
parser.

> I will never understand why so many people try to parse/scrape
> HTML/XML with regexes...

Why?  Because some times it is good enough to get the job done easily.


From thebrasse at gmail.com  Wed Jul  8 18:43:59 2009
From: thebrasse at gmail.com (=?ISO-8859-1?Q?Mattias_Br=E4ndstr=F6m?=)
Date: Wed, 8 Jul 2009 15:43:59 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<MeqdnTn37r9N-s_XnZ2dnUVZ_jCdnZ2d@pdx.net>
Message-ID: <48bcf21c-4c40-4d49-9966-e0cedfdf206e@d4g2000yqa.googlegroups.com>

On Jul 6, 11:15?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> brasse wrote:
> > I have been thinking about how write exception safe constructors in
> > Python. By exception safe I mean a constructor that does not leak
> > resources when an exception is raised within it.
>
> ...
> ?> As you can see this is less than straight forward. Is there some kind
> ?> of best practice that I'm not aware of?
>
> Not so tough. ?Something like this tweaked version of your example:
>
> class Foo(object):
> ? ? ?def __init__(self, name, fail=False):
> ? ? ? ? ?self.name = name
> ? ? ? ? ?if not fail:
> ? ? ? ? ? ? ?print '%s.__init__(%s)' % (type(self).__name__, name)
> ? ? ? ? ?else:
> ? ? ? ? ? ? ?print '%s.__init__(%s), FAIL' % (type(self).__name__, name)
> ? ? ? ? ? ? ?raise ValueError('Asked to fail: %r' % fail)
>
> ? ? ?def close(self):
> ? ? ? ? ?print '%s.close(%s)' % (type(self).__name__, self.name)
>
> class Bar(object):
> ? ? ?def __init__(self):
> ? ? ? ? ?unwind = []
> ? ? ? ? ?try:
> ? ? ? ? ? ? ?self.a = Foo('a')
> ? ? ? ? ? ? ?unwind.append(a)
> ? ? ? ? ? ? ?self.b = Foo('b', fail=True)
> ? ? ? ? ? ? ?unwind.append(b)
> ? ? ? ? ? ? ?...
> ? ? ? ? ?except Exception, why:
> ? ? ? ? ? ? ?while unwind):
> ? ? ? ? ? ? ? ? ?unwind.pop().close()
> ? ? ? ? ? ? ?raise
>
> bar = Bar()
>

OK. That's another way. I have been thinking about this some more and
right now I am experimenting with a decorator that could help me do
these kinds of things. This is what I have right now:

import functools

class Foo(object):
    def __init__(self, name, fail=False):
        self.name = name
        self.closed = False
        if not fail:
            print '%s.__init__(%s)' % (self.__class__.__name__,
self.name)
        else:
            print '%s.__init__(%s), FAIL' % (self.__class__.__name__,
                                             self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)

def safe(f):
    @functools.wraps(f)
    def wrapper(self, *args, **kwargs):
        variables = []
        def recorder(self, name, value):
            if name != '__class__':
                variables.append(name)
            object.__setattr__(self, name, value)

        class Customized(object): pass
        setattr(Customized, '__setattr__', recorder)
        old_class = self.__class__
        self.__class__ = Customized

        try:
            f(self, *args, **kwargs)
            self.__class__ = old_class
        except:
            # clean up objects created in __init__ (i.e. the call to f
())
            for name in reversed(variables):
                o = getattr(self, name)
                if hasattr(o, 'close'):
                    o.close()
            raise
    return wrapper

class Bar(object):
    @safe
    def __init__(self):
        self.a = Foo('a')
        self.b = Foo('b')
        self.c = Foo('c', fail=True)

bar = Bar()

The safe decorator will record all attributes created on self. If an
exception is raised during the execution of the decorated constructor
it will call close on all the recorded objects. I realize that this
decorator still needs a lot of work before it is usable, but I think
it illustrates the concept. It might even be possible for the
decorator to create a close/cleanup method dynamically.

To have a decorator like this that actually worked would be great
since it would remove the need to write error prone cleanup code. Any
thoughts?

:.:: mattias

> --Scott David Daniels
> Scott.Dani... at Acm.Org



From fabiofz at gmail.com  Wed Jul  8 19:01:40 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Wed, 8 Jul 2009 20:01:40 -0300
Subject: Pydev 1.4.7 Released
Message-ID: <cfb578b20907081601o7e6acb7dq61672f3df43065be@mail.gmail.com>

Hi All,

Pydev and Pydev Extensions 1.4.7 have been released

Details on Pydev Extensions: http://www.fabioz.com/pydev
Details on Pydev: http://pydev.sf.net
Details on its development: http://pydev.blogspot.com

Release Highlights in Pydev Extensions:
-----------------------------------------------------------------

* The interactive console can be used on the remote debugger
* Remote debugger properly redirects contents from the server on multiple runs.
* Providing context-independent completions when other completions are
not available (until now, it only gave those completions for method
parameters)
* The number of chars required to show the context-insensitive
completion can now be customized.
* Fixed problem with Eclipse 3.5: "Invalid Thread Access" when trying
to rename a class


Release Highlights in Pydev:
----------------------------------------------

* Iron Python support
* Fixed issue when configuring interpreter on Eclipse 3.3 and 3.2 (was
using API only available in 3.4)
* Google App Engine
      o Popup menus for google app engine are now working with eclipse 3.2
      o Fixed issues when google app engine project has spaces in path
* Launching
      o Ctrl+F9 can be used to run as unit-test and select which tests
will be run
      o F9 will now run the current editor based on the project type
      o Changed run icons
      o Run configurations can be created for the project
      o Run as unit-test can have --filter and --tests as a parameter
set in the run configuration
* Shift left can now shift even when there are less chars than the
required indent string
* Top-level modules on .egg files are now properly recognized
* Auto-config fixed
* Fixed problem when .pydevproject was not a parseable xml file (the
pydev package explorer wouldn't work because of that)
* When a new interpreter is created, it's properly selected in the tree
* Code-completion better heuristic when analyzing function return
that's called on self.
* Code-completion in the interactive console now handles import
sections correctly
* Code formatter: Spaces after square and curly braces are no longer
changed when an unary operator is found afterwards
* Fixed problem when recognizing encodings (regexp was not correct)



What is PyDev?
---------------------------

PyDev is a plugin that enables users to use Eclipse for Python, Jython
and Iron Python development -- making Eclipse a first class Python IDE
-- It comes with many goodies such as code completion, syntax
highlighting, syntax analysis, refactor, debug and many others.


Cheers,

-- 
Fabio Zadrozny
------------------------------------------------------
Software Developer

Aptana
http://aptana.com/python

Pydev Extensions
http://www.fabioz.com/pydev

Pydev - Python Development Environment for Eclipse
http://pydev.sf.net
http://pydev.blogspot.com


From helvinlui at gmail.com  Wed Jul  8 19:10:37 2009
From: helvinlui at gmail.com (Helvin)
Date: Wed, 8 Jul 2009 16:10:37 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org>
Message-ID: <60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>

On Jul 8, 9:23?pm, Phil Thompson <p... at riverbankcomputing.com> wrote:
> On Wed, 08 Jul 2009 11:11:51 +0200, "Diez B. Roggisch"
> <de... at nospam.web.de>
> wrote:
>
>
>
>
>
> > Helvin wrote:
>
> >> Hi experts!
>
> >> I'm developing a GUI for a software using PyQT, and need 3D
> >> visualization. Should I use PyOpenGL or VTK?
> >> I understand that the PyQt package comes with a opengl module. What
> >> else would I need? I think I need to download opengl. but how? where?
> >> I have VTK and pyVTK installed, but I don't know how to use it in my
> >> code, as when I run it, an error says it can't find the vtk module.
>
> > VTK won't mix with Qt. And I don't think you need to download opengl - it
> > either comes with your system (or gfx-drivers), or not. I'm not sure if
> Qt
> > actually wraps the OpenGL api itself, AFAIK it doesn't, so you need
> > PyOpenGL I guess.
>
> VTK has explicit support for both Qt (ie. via C++) and PyQt.
>
> Phil

Thanks for the fast replies! I will look into how to use VTK now.
Where would I find VTK's explicit support for PyQt?

Because I have installed VTK (using its installer) and pyVTK (using
its setup.py file), but how do I actually use it in my code? According
to: http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521455.html,
I have tried 'import vtk', but python can't find the vtk module.

Thanks a million!
Helvin


From psimon at sonic.net  Wed Jul  8 19:18:02 2009
From: psimon at sonic.net (Paul Simon)
Date: Wed, 8 Jul 2009 16:18:02 -0700
Subject: tkinter problem
Message-ID: <4a55292f$0$95538$742ec2ed@news.sonic.net>

I have the "tkinter" problem and need some assistance to straighten it out.
>From the web page "http://wiki.python.org/moin/TkInter" I tested as in "step
1" and cannot import "_tkinter." I do not have that file on my computer, but
do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
This  python stuff is great, but the documentation frequently
feels like it is just a bit out of my grasp. I realize that all of this is
free but I understand the instructions on the web page to repair only to the
point of confusion. I'm not an expert. How do I modify my python
configuration? Is there a file that needs to be edited? Which setup.py file
do I use? Make? or python setup.py build and python setup.py install?
Thanks. I appreciate your help.
Paul Simon 




From rhodri at wildebst.demon.co.uk  Wed Jul  8 19:20:59 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 09 Jul 2009 00:20:59 +0100
Subject: regex help
In-Reply-To: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
Message-ID: <op.uwru49xna8ncjz@gnudebst>

On Wed, 08 Jul 2009 23:06:22 +0100, David <david.bramer at googlemail.com>  
wrote:

> Hi
>
> I have a few regexs I need to do, but im struggling to come up with a
> nice way of doing them, and more than anything am here to learn some
> tricks and some neat code rather than getting an answer - although
> thats obviously what i would like to get to.
>
> Problem 1 -
>
> <span class="chg"
>                 id="ref_678774_cp">(25.47%)</span><br>
>
> I want to extract 25.47 from here - so far I've tried -
>
> xPer = re.search('<span class="chg" id="ref_"'+str(xID.group(1))+'"_cp
> \">(.*?)%', content)

Supposing that str(xID.group(1)) == "678774", let's see how that string
concatenation turns out:

<span class="chg" id="ref_"678774"_cp">(.*?)%

The obvious problems here are the spurious double quotes, the spurious
(but harmless) escaping of a double quote, and the lack of (escaped)
backslash and (escaped) open parenthesis.  The latter you can always
strip off later, but the first sink the match rather thoroughly.

>
> and
>
> xPer = re.search('<span class=\"chg\" id=\"ref_"+str(xID.group(1))+"_cp
> \">\((\d*)%\)</span><br>', content)

With only two single quotes present, the biggest problem should be obvious.

Unfortunately if you just fix the obvious in either of the two regular
expressions, you're setting yourself up for a fall later on.  As The Fine
Manual says right at the top of the page on the re module
(http://docs.python.org/library/re.html), you want to be using raw string
literals when you're dealing with regular expressions, because you want
the backslashes getting through without being interpreted specially by
Python's own parser.  As it happens you get away with it in this case,
since neither '\d' nor '\(' have a special meaning to Python, so aren't
changed, and '\"' is interpreted as '"', which happens to be the right
thing anyway.


> Problem 2 -
>
> <td>&nbsp;</td>
>
> <td width="1%" class=key>Open:
> </td>
> <td width="1%" class=val>5.50
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>Mkt Cap:
> </td>
> <td width="1%" class=val>6.92M
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>P/E:
> </td>
> <td width="1%" class=val>21.99
> </td>
>
>
> I want to extract the open, mkt cap and P/E values - but apart from
> doing loads of indivdual REs which I think would look messy, I can't
> think of a better and neater looking way. Any ideas?

What you're trying to do is inherently messy.  You might want to use
something like BeautifulSoup to hide the mess, but never having had
cause to use it myself I couldn't say for sure.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From clp2 at rebertia.com  Wed Jul  8 19:22:14 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 8 Jul 2009 16:22:14 -0700
Subject: tkinter problem
In-Reply-To: <4a55292f$0$95538$742ec2ed@news.sonic.net>
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
Message-ID: <50697b2c0907081622w11ed9275mcce5c0377cafd273@mail.gmail.com>

On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
> I have the "tkinter" problem and need some assistance to straighten it out.
> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in "step
> 1" and cannot import "_tkinter." I do not have that file on my computer, but
> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
> This ?python stuff is great, but the documentation frequently
> feels like it is just a bit out of my grasp. I realize that all of this is
> free but I understand the instructions on the web page to repair only to the
> point of confusion. I'm not an expert. How do I modify my python
> configuration? Is there a file that needs to be edited? Which setup.py file
> do I use? Make? or python setup.py build and python setup.py install?
> Thanks. I appreciate your help.

- How did you install Python?
- What Linux distro are you using?

Cheers,
Chris
-- 
http://blog.rebertia.com


From robert.kern at gmail.com  Wed Jul  8 19:29:26 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 08 Jul 2009 18:29:26 -0500
Subject: PyQt GUI
In-Reply-To: <60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
Message-ID: <h33a4m$ic$1@ger.gmane.org>

On 2009-07-08 18:10, Helvin wrote:

> Thanks for the fast replies! I will look into how to use VTK now.
> Where would I find VTK's explicit support for PyQt?

Wrapping/Python/vtk/qt4/ in the VTK sources.

> Because I have installed VTK (using its installer) and pyVTK (using
> its setup.py file), but how do I actually use it in my code? According
> to: http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521455.html,
> I have tried 'import vtk', but python can't find the vtk module.

Then you have not installed VTK's Python bindings correctly. Note that pyVTK is 
just a library for manipulating VTK files. The VTK Python bindings are part of 
VTK's distribution itself. Exactly how did you install VTK? Did you compile it 
yourself?

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From ldo at geek-central.gen.new_zealand  Wed Jul  8 19:49:54 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Thu, 09 Jul 2009 11:49:54 +1200
Subject: walking a directory with very many files
References: <5f51bc62-16fb-4e24-ac6c-1e5ea3ee596c@d38g2000prn.googlegroups.com>
	<mailman.1560.1245011753.8015.python-list@python.org>
	<pan.2009.06.15.04.56.07@REMOVE.THIS.cybersource.com.au>
	<234b19ac-7baf-4356-9fe5-37d00146d982@z9g2000yqi.googlegroups.com>
	<h19lpc$omc$2@lust.ihug.co.nz>
	<20090617091858.432f89ca@malediction>
	<eCZZl.19176$y61.15588@news-server.bigpond.net.au>
	<20090617110705.7e7c423f@malediction>
	<%Zv_l.19493$y61.5958@news-server.bigpond.net.au>
	<h1f987$1fe$7@lust.ihug.co.nz>
	<J_Q_l.19655$y61.10309@news-server.bigpond.net.au>
	<h1i83b$ojg$3@lust.ihug.co.nz>
	<0058d36a$0$9759$c3e8da3@news.astraweb.com>
	<h1qos2$ta2$1@services.telesweet.net>
	<pan.2009.06.24.02.20.10@REMOVE.THIS.cybersource.com.au>
	<h1scda$mrl$5@lust.ihug.co.nz>
	<kCk0m.406$ze1.243@news-server.bigpond.net.au>
Message-ID: <h33bb2$ges$1@lust.ihug.co.nz>

In message <kCk0m.406$ze1.243 at news-server.bigpond.net.au>, Lie Ryan wrote:

> Lawrence D'Oliveiro wrote:
>
>> ... certainly it is characteristic of GUIs to show you all 400,000 files
>> in a directory, or at least try to do so, and either hang for half an
>> hour or run out of memory and crash, rather than give you some
>> intelligent way of prefiltering the file display up front.
> 
> In many debugging cases, you don't even know what to filter ...

So pick a random sample to start with. Do you know of a GUI tool that can do 
that?



From mensanator at aol.com  Wed Jul  8 20:03:42 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 8 Jul 2009 17:03:42 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com>
Message-ID: <4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com>

On Jul 7, 12:47?am, Mensanator <mensana... at aol.com> wrote:
> On Jul 7, 12:16 am, casevh <cas... at gmail.com> wrote:
>
> > I discovered a serious bug with comparisons and have posted alpha2
> > which fixes that bug and adds Unicode support for Python 2.x
>
> > casevh
>
> Damn! I was just congatulating myself for pulling off
> a hat trick (there had been no point in downloading
> 3.x without gmpy so I have been putting it off):
>
> - installing Python 3.1
> - installing gmpy 1.10
> - converting my Collatz Function library to 3.1 syntax
>
> And it all worked smoothly, just had to add parentheses
> to my print statements, change xrange to range and all
> my / to // (the library is exclusively integer). I had
> gmpy running in my library on 3.1 in about 10 minutes.
>
> So I'll have to re-do the gmpy install. Shouldn't be
> any big deal.
>
> I started doing some real world tests. Generally, things
> look good (nothing crashes, timing looks not bad) but
> I'm getting some funny results on one of my tests, so
> I'll report back when I have more information.

As I said, I was getting funny results from one of my tests.

It seemed to work ok, but timing varied from 2 to 88 seconds,
which seemed odd. The other tests were generally consistent
for a given environment (cpu speed, OS, Python version, gmpy
version).

At some point I watched the memory usage profile from Windows.
On the same machine I have both Python 2.6 and 3.1 installed,
with the appropriate gmpy 1.10 version loaded for each.

In Python 2.6, it looks like this:

memory usage profile Python 2.6 gmpy 1.1 Vista

      /--------------\  /-------\ .....RESTART SHELL
     /               .\/         \
____/                .            \________
   .                 .
   .                 .
   start of RUN      start of RUN

The first "start of RUN" is the first time the test is run
(from IDLE). That change in usage represents about 700 MB
(I'm testing really BIG numbers, up to 500 million digits).

The memory remains allocated after the program terminates
(the flat plateau). When I run a second time, we see the
allocation dip, then climb back up to the plateau, so it
appears that the allocation never climbs above 1.1 GB.

Finally, doing a RESTART SHELL seems to completely free
the allocated memory. I assume this is normal behaviour.

With Python 3.1, it get this profile:

memory usage profile Python 3.1 gmpy 1.1 Vista

                         /-
                        / |
      /----------------/   \------\ .....RESTART SHELL
     /                 .           \
____/                  .            \___________
   .                   .
   .                   .
   start of RUN        start of RUN

Here, at the start of the second RUN, it appears that new
memory is allocated BEFORE the previous is cleared. Is this
a quirk in the way 3.1 behaves? Here, the peak usage climbs
to 1.8 GB which I think causes VM thrashing accounting for
the increased execution times.

My guess is that gmpy is provoking, but not causing this
behaviour.

The actual test is:

t0 = time.time()
n=10
for k in range(1,n):
  for i in range(1,n-2):
    print((str(cf.gmpy.numdigits(cf.Type12MH(k,i))).zfill(n)),end=' ')
  print()
print()
t1 = time.time()


The library function Type12MH is:

def Type12MH(k,i):
    """Find ith, kth Generation Type [1,2] Mersenne Hailstone using
the closed form equation

    Type12MH(k,i)
    k: generation
    i: member of generation
    returns Hailstone (a)
    """
    ONE = gmpy.mpz(1)
    TWO = gmpy.mpz(2)
    SIX = gmpy.mpz(6)
    NIN = gmpy.mpz(9)

    if (k<1) or (i<1): return 0

    i = gmpy.mpz(i)
    k = gmpy.mpz(k)

    # a = (i-1)*9**(k-1) + (9**(k-1) - 1)//2 + 1
    # return 2**(6*a - 1) - 1

    a = (i-ONE)*NIN**(k-ONE) + (NIN**(k-ONE) - ONE)//TWO + ONE
    return TWO**(SIX*a - ONE) - ONE

##  Sample runs
##
##  Test 1 - create numbers up to 500 million digits
##
##  0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##  0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##  0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##  0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##  0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##  0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##  0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##  0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##  0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##  15.5460000038
##  >>> ================================ RESTART
================================
##  >>>
##  0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##  0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##  0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##  0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##  0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##  0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##  0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##  0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##  0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##  3.06299996376



From psimon at sonic.net  Wed Jul  8 20:16:15 2009
From: psimon at sonic.net (Paul Simon)
Date: Wed, 8 Jul 2009 17:16:15 -0700
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
Message-ID: <4a5536d4$0$95520$742ec2ed@news.sonic.net>


"Chris Rebert" <clp2 at rebertia.com> wrote in message 
news:mailman.2863.1247095339.8015.python-list at python.org...
On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
> I have the "tkinter" problem and need some assistance to straighten it 
> out.
> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in 
> >"step
> 1" and cannot import "_tkinter." I do not have that file on my computer, 
> but
> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
> This python stuff is great, but the documentation frequently
> feels like it is just a bit out of my grasp. I realize that all of this is
> free but I understand the instructions on the web page to repair only to 
> the
> point of confusion. I'm not an expert. How do I modify my python
> configuration? Is there a file that needs to be edited? Which setup.py 
> file
> do I use? Make? or python setup.py build and python setup.py install?
> Thanks. I appreciate your help.

- How did you install Python?
- What Linux distro are you using?

Cheers,
Chris
-- 
http://blog.rebertia.com
I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
exactly how I installed Python.  Originally I had installed 2.5 from RPM but
2.6 was not available for my distro (2008.1) in RPM.  I downloaded something
from python.org and installed.  Not sure if it was tarball or zip file.

Paul




From casevh at gmail.com  Wed Jul  8 20:38:06 2009
From: casevh at gmail.com (casevh)
Date: Wed, 8 Jul 2009 17:38:06 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com> 
	<4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com>
Message-ID: <4ae1e16f-124b-49c8-8364-36c59419be9b@d32g2000yqh.googlegroups.com>

On Jul 8, 5:03?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 7, 12:47?am, Mensanator <mensana... at aol.com> wrote:
>
>
>
> > On Jul 7, 12:16 am, casevh <cas... at gmail.com> wrote:
>
> > > I discovered a serious bug with comparisons and have posted alpha2
> > > which fixes that bug and adds Unicode support for Python 2.x
>
> > > casevh
>
> > Damn! I was just congatulating myself for pulling off
> > a hat trick (there had been no point in downloading
> > 3.x without gmpy so I have been putting it off):
>
> > - installing Python 3.1
> > - installing gmpy 1.10
> > - converting my Collatz Function library to 3.1 syntax
>
> > And it all worked smoothly, just had to add parentheses
> > to my print statements, change xrange to range and all
> > my / to // (the library is exclusively integer). I had
> > gmpy running in my library on 3.1 in about 10 minutes.
>
> > So I'll have to re-do the gmpy install. Shouldn't be
> > any big deal.
>
> > I started doing some real world tests. Generally, things
> > look good (nothing crashes, timing looks not bad) but
> > I'm getting some funny results on one of my tests, so
> > I'll report back when I have more information.
>
> As I said, I was getting funny results from one of my tests.
>
> It seemed to work ok, but timing varied from 2 to 88 seconds,
> which seemed odd. The other tests were generally consistent
> for a given environment (cpu speed, OS, Python version, gmpy
> version).
>
> At some point I watched the memory usage profile from Windows.
> On the same machine I have both Python 2.6 and 3.1 installed,
> with the appropriate gmpy 1.10 version loaded for each.
>
> In Python 2.6, it looks like this:
>
> memory usage profile Python 2.6 gmpy 1.1 Vista
>
> ? ? ? /--------------\ ?/-------\ .....RESTART SHELL
> ? ? ?/ ? ? ? ? ? ? ? .\/ ? ? ? ? \
> ____/ ? ? ? ? ? ? ? ?. ? ? ? ? ? ?\________
> ? ?. ? ? ? ? ? ? ? ? .
> ? ?. ? ? ? ? ? ? ? ? .
> ? ?start of RUN ? ? ?start of RUN
>
> The first "start of RUN" is the first time the test is run
> (from IDLE). That change in usage represents about 700 MB
> (I'm testing really BIG numbers, up to 500 million digits).
>
> The memory remains allocated after the program terminates
> (the flat plateau). When I run a second time, we see the
> allocation dip, then climb back up to the plateau, so it
> appears that the allocation never climbs above 1.1 GB.
>
> Finally, doing a RESTART SHELL seems to completely free
> the allocated memory. I assume this is normal behaviour.
>
> With Python 3.1, it get this profile:
>
> memory usage profile Python 3.1 gmpy 1.1 Vista
>
> ? ? ? ? ? ? ? ? ? ? ? ? ?/-
> ? ? ? ? ? ? ? ? ? ? ? ? / |
> ? ? ? /----------------/ ? \------\ .....RESTART SHELL
> ? ? ?/ ? ? ? ? ? ? ? ? . ? ? ? ? ? \
> ____/ ? ? ? ? ? ? ? ? ?. ? ? ? ? ? ?\___________
> ? ?. ? ? ? ? ? ? ? ? ? .
> ? ?. ? ? ? ? ? ? ? ? ? .
> ? ?start of RUN ? ? ? ?start of RUN
>
> Here, at the start of the second RUN, it appears that new
> memory is allocated BEFORE the previous is cleared. Is this
> a quirk in the way 3.1 behaves? Here, the peak usage climbs
> to 1.8 GB which I think causes VM thrashing accounting for
> the increased execution times.
>

Hmmm. It looks like memory is not being release properly. I don't see
that behavior under Linux. The running time is a very consistent 1.35
seconds. I'm traveling at the moment so it will be at least a week
before I can test under Windows.

Thanks for the report. I'll try to see if I can figure out what is
going on.

casevh
> My guess is that gmpy is provoking, but not causing this
> behaviour.
>
> The actual test is:
>
> t0 = time.time()
> n=10
> for k in range(1,n):
> ? for i in range(1,n-2):
> ? ? print((str(cf.gmpy.numdigits(cf.Type12MH(k,i))).zfill(n)),end=' ')
> ? print()
> print()
> t1 = time.time()
>
> The library function Type12MH is:
>
> def Type12MH(k,i):
> ? ? """Find ith, kth Generation Type [1,2] Mersenne Hailstone using
> the closed form equation
>
> ? ? Type12MH(k,i)
> ? ? k: generation
> ? ? i: member of generation
> ? ? returns Hailstone (a)
> ? ? """
> ? ? ONE = gmpy.mpz(1)
> ? ? TWO = gmpy.mpz(2)
> ? ? SIX = gmpy.mpz(6)
> ? ? NIN = gmpy.mpz(9)
>
> ? ? if (k<1) or (i<1): return 0
>
> ? ? i = gmpy.mpz(i)
> ? ? k = gmpy.mpz(k)
>
> ? ? # a = (i-1)*9**(k-1) + (9**(k-1) - 1)//2 + 1
> ? ? # return 2**(6*a - 1) - 1
>
> ? ? a = (i-ONE)*NIN**(k-ONE) + (NIN**(k-ONE) - ONE)//TWO + ONE
> ? ? return TWO**(SIX*a - ONE) - ONE
>
> ## ?Sample runs
> ##
> ## ?Test 1 - create numbers up to 500 million digits
> ##
> ## ?0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
> 0000000013
> ## ?0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
> 0000000107
> ## ?0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
> 0000000952
> ## ?0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
> 0000008560
> ## ?0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
> 0000077028
> ## ?0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
> 0000693246
> ## ?0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
> 0006239209
> ## ?0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
> 0056152869
> ## ?0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
> 0505375816
> ##
> ## ?15.5460000038
> ## ?>>> ================================ RESTART
> ================================
> ## ?>>>
> ## ?0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
> 0000000013
> ## ?0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
> 0000000107
> ## ?0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
> 0000000952
> ## ?0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
> 0000008560
> ## ?0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
> 0000077028
> ## ?0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
> 0000693246
> ## ?0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
> 0006239209
> ## ?0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
> 0056152869
> ## ?0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
> 0505375816
> ##
> ## ?3.06299996376



From no.email at please.post  Wed Jul  8 21:20:10 2009
From: no.email at please.post (kj)
Date: Thu, 9 Jul 2009 01:20:10 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mailman.2671.1246866295.8015.python-list@python.org>
Message-ID: <h33gka$19p$1@reader1.panix.com>

In <mailman.2671.1246866295.8015.python-list at python.org> Martin Vilcans <martin at librador.com> writes:

>On Fri, Jul 3, 2009 at 4:05 PM, kj<no.email at please.post> wrote:
>> I'm will be teaching a programming class to novices, and I've run
>> into a clear conflict between two of the principles I'd like to
>> teach: code clarity vs. code reuse. =A0I'd love your opinion about
>> it.

>In general, code clarity is more important than reusability.
>Unfortunately, many novice programmers have the opposite impression. I
>have seen too much convoluted code written by beginners who try to
>make the code generic. Writing simple, clear, to-the-point code is
>hard enough as it is, even when not aiming at making it reusable.

>If in the future you see an opportunity to reuse the code, then and
>only then is the time to make it generic.

>YAGNI is a wonderful principle.

Thanks!

kynn



From no.email at please.post  Wed Jul  8 21:21:22 2009
From: no.email at please.post (kj)
Date: Thu, 9 Jul 2009 01:21:22 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>	<f782707a0907060044o23dd9319q947ab5237846315a@mail.gmail.com>
	<mailman.2673.1246866666.8015.python-list@python.org>
	<fMKdnf0dlOXTcMzXnZ2dnUVZ_t2dnZ2d@pdx.net>
Message-ID: <h33gmi$19p$2@reader1.panix.com>

In <fMKdnf0dlOXTcMzXnZ2dnUVZ_t2dnZ2d at pdx.net> Scott David Daniels <Scott.Daniels at Acm.Org> writes:

>First, a quote which took me a bit to find:
>     Thomas William K??rner paraphrasing Polya and Svego
>     in A Companion to Analysis:
>         Recalling that 'once is a trick, twice is a method,
>         thrice is a theorem, and four times a theory,' we
>         seek to codify this insight.

Good stuff.

>Let us apply this insight:
>     Suppose in writing code, we pretty much go with that.
>A method is something you notice, a theorem is a function, and
>a theory is a generalized function.

>Even though we like DRY ("don't repeat yourself") as a maxim, let
>it go the first time and wait until you see the pattern (a possible
>function).  I'd go with a function first, a pair of functions, and
>only then look to abstracting the function.

Thanks!

kynn


From jcd at sdf.lonestar.org  Wed Jul  8 22:10:47 2009
From: jcd at sdf.lonestar.org (J. Clifford Dyer)
Date: Wed, 08 Jul 2009 22:10:47 -0400
Subject: count
In-Reply-To: <7xbpnuzw4u.fsf@ruckus.brouhaha.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com>  <7xbpnuzw4u.fsf@ruckus.brouhaha.com>
Message-ID: <1247105447.4532.8.camel@mctell>

On Wed, 2009-07-08 at 14:45 -0700, Paul Rubin wrote:
> aahz at pythoncraft.com (Aahz) writes:
> > >Avoid that len(tuple(g)), use something like the following, it's lazy
> > >and saves some memory.
> > The question is whether it saves time, have you tested it?
> 
> len(tuple(xrange(100000000))) ... hmm.

timer.py
--------
from datetime import datetime

def tupler(n):
    return len(tuple(xrange(n)))

def summer(n):
    return sum(1 for x in xrange(n))

def test_func(f, n):
    print f.__name__,
    start = datetime.now()
    print f(n)
    end = datetime.now()
    print "Start: %s" % start
    print "End: %s" % end
    print "Duration: %s" % (end - start,)

if __name__ == '__main__':
    test_func(summer, 10000000)
    test_func(tupler, 10000000)
    test_func(summer, 100000000)
    test_func(tupler, 100000000)

$ python timer.py
summer 10000000
Start: 2009-07-08 22:02:13.216689
End: 2009-07-08 22:02:15.855931
Duration: 0:00:02.639242
tupler 10000000
Start: 2009-07-08 22:02:15.856122
End: 2009-07-08 22:02:16.743153
Duration: 0:00:00.887031
summer 100000000
Start: 2009-07-08 22:02:16.743863
End: 2009-07-08 22:02:49.372756
Duration: 0:00:32.628893
Killed
$ 

Note that "Killed" did not come from anything I did.  The tupler just
bombed out when the tuple got too big for it to handle.  Tupler was
faster for as large an input as it could handle, as well as for small
inputs (test not shown).



From no.email at please.post  Wed Jul  8 22:19:25 2009
From: no.email at please.post (kj)
Date: Thu, 9 Jul 2009 02:19:25 +0000 (UTC)
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
Message-ID: <h33k3d$2uu$1@reader1.panix.com>

In <mailman.2700.1246895025.8015.python-list at python.org> Tim Rowe <digitig at gmail.com> writes:

>2009/7/4 kj <no.email at please.post>:

>> Precisely. =A0As I've stated elsewhere, this is an internal helper
>> function, to be called only a few times under very well-specified
>> conditions. =A0The assert statements checks that these conditions
>> are as intended. =A0I.e. they are checks against the module writer's
>> programming errors.

>Good for you. I'm convinced that you have used the assertion
>appropriately, and the fact that so many here are unable to see that
>looks to me like a good case for teaching the right use of assertions.
>For what it's worth, I read assertions at the beginning of a procedure
>as part of the specification of the procedure, and I use them there in
>order to document the procedure. An assertion in that position is for
>me a statement to the user of the procedure "it's your responsibility
>to make sure that you never call this procedure in such a way as to
>violate these conditions". They're part of a contract, as somebody
>(maybe you) pointed out.

>As somebody who works in the safety-critical domain, it's refreshing
>to see somebody teaching students to think about the circumstances in
>which a procedure can legitimately be called. The hostility you've
>received to that idea is saddening, and indicative of why there's so
>much buggy software out there.

Thanks for the encouragement.

When I teach programming, the students are scientists.  For the
stuff they do, correctness of the code trumps everything else.  I
teach them to view assertions as way of translating their assumptions
into code.  And by this I mean not only assumptions about the
correctness of their code (the typical scope of assertions), but
also, more broadly, assumptions about the data that they are dealing
with (which often comes from external sources with abysmal quality
control).

My scientific code is jam-packed with assertions.  I can't count
the number of times that one such lowly assertion saved me from a
silent but potentially disastrous bug.  And yes I find it distressing
that so so few programmers in my line of work use assertions at
all.

kynn


From vel.accel at gmail.com  Wed Jul  8 22:23:53 2009
From: vel.accel at gmail.com (dieter)
Date: Wed, 8 Jul 2009 19:23:53 -0700 (PDT)
Subject: PyGtk Depends on Numeric
Message-ID: <1ebe9314-9434-459a-bd3e-2b2386a35f1b@n11g2000yqb.googlegroups.com>

Get with the times people and port to numpy. :P
Don't you think its about time?

~Pete


From jpablo.romero at gmail.com  Wed Jul  8 22:55:53 2009
From: jpablo.romero at gmail.com (=?ISO-8859-1?Q?Juan_Pablo_Romero_M=E9ndez?=)
Date: Wed, 8 Jul 2009 21:55:53 -0500
Subject: PyQt GUI
In-Reply-To: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
Message-ID: <e6507ac70907081955s7d69c816gecf41aeb42502269@mail.gmail.com>

I use OpenInventor (Coin3d) which have a python binding called "pivy".
It works great.

http://pivy.coin3d.org/

Juan Pablo

2009/7/8 Helvin <helvinlui at gmail.com>:
> Hi experts!
>
> I'm developing a GUI for a software using PyQT, and need 3D
> visualization. Should I use PyOpenGL or VTK?
> I understand that the PyQt package comes with a opengl module. What
> else would I need? I think I need to download opengl. but how? where?
> I have VTK and pyVTK installed, but I don't know how to use it in my
> code, as when I run it, an error says it can't find the vtk module.
>
> Help would be sooooo appreciated!
> Helvin
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From fatkinson at mishmash.com  Wed Jul  8 23:53:12 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Wed, 08 Jul 2009 20:53:12 -0700
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
Message-ID: <cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>

On Wed, 08 Jul 2009 12:29:54 +0200, Piet van Oostrum <piet at cs.uu.nl>
wrote:

>Something like:
>
>#! /usr/bin/env python
>
>import cgi
>from os import getenv
>
>print "Content-type: text/html"
>print
>
>ipaddr = (getenv("HTTP_CLIENT_IP") or
>      getenv("HTTP_X_FORWARDED_FOR") or
>      getenv("HTTP_X_FORWARDED_FOR") or
>      getenv("REMOTE_ADDR") or
>      "UNKNOWN")
>
>print ipaddr

That did it.  

I wonder why they don't just have a function to return it instead of
putting you through all of that?  

At any rate, it works.  

Regards, 




                                                      Fred 


From nobody at nowhere.com  Thu Jul  9 00:38:32 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 09 Jul 2009 05:38:32 +0100
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
	<cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>
Message-ID: <pan.2009.07.09.04.38.32.94000@nowhere.com>

On Wed, 08 Jul 2009 20:53:12 -0700, Fred Atkinson wrote:

>>ipaddr = (getenv("HTTP_CLIENT_IP") or
>>      getenv("HTTP_X_FORWARDED_FOR") or
>>      getenv("HTTP_X_FORWARDED_FOR") or
>>      getenv("REMOTE_ADDR") or
>>      "UNKNOWN")
>>
>>print ipaddr
> 
> That did it.  
> 
> I wonder why they don't just have a function to return it instead of
> putting you through all of that?  

There's no unambiguous definition of "client IP", so you have to choose
which definition you want.

REMOTE_ADDR is set to the actual IP address from which the connection
originated (from getpeername()). If the connection was made via a proxy,
REMOTE_ADDR will contain the IP address of the proxy.

The others are set from HTTP headers. Proxies often add Client-IP
or X-Forwarded-For headers to indicate the originating IP address. OTOH,
there's no way to know if the headers are accurate; nuisance users may
add these headers to confuse poorly-conceived banning mechanisms.



From sajmikins at gmail.com  Thu Jul  9 01:05:57 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Wed, 8 Jul 2009 22:05:57 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
Message-ID: <b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>

(I wanted to reply to a few messages in one post so I quoted them all
below. Let me know if this is bad etiquette.)

On Jul 8, 8:23 am, kj <no.em... at please.post> wrote:
> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5... at q11g2000yqi.googlegroups.com> Simon Forman <sajmik... at gmail.com> writes:
>
> >Frankly, I'm of the impression that it's a mistake not to start
> >teaching programming with /the bit/ and work your way up from there.
> >I'm not kidding. I wrote a (draft) article about this: "Computer
> >Curriculum"http://docs.google.com/View?id=dgwr777r_31g4572gp4
> >I really think the only good way to teach computers and programming is
> >to start with a bit, and build up from there. "Ontology recapitulates
> >phylogeny"
>
> I happen to be very receptive to this point of view.  I had the
> benefit of that sort of training (one of the first computer courses
> I took started, believe it or not, with Turing machines, through
> coding in machine language, and compiler theory, and all the way
> up to dabbling with Unix!), and I suspect that the reason it is
> sometimes difficult for me to explain even relatively simple-looking
> things to others is that I have this background that I unconsciously,
> and incorrectly, take for granted in others...  There is this

Yes!  Once the concepts become so familiar that you call them
"intuitive" it seems to be very difficult to remember what they were
like before.

Something like "a = b" becomes "obvious" only after you've
internalized the preceding concepts.


> persistent idea "out there" that programming is a very accessible
> skill, like cooking or gardening, anyone can do it, and even profit
> from it, monetarily or otherwise, etc., and to some extent I am

Programming is not like any other human activity.  I've been reading
some of Prof. Dijkstra's EWDs in the last few days.  In one [1] he
says, "automatic computers embody not only one radical novelty but two
of them", to wit: First, the huge scales that must be understood,
"from a bit to a few hundred megabytes, from a microsecond to a half
an hour of computing"; and second, "that the automatic computer is our
first large-scale digital device" which our until-now overwhelmingly
analog experience does not prepare us to deal with well.

He talks about how "when all is said and done, the only thing
computers can do for us is to manipulate symbols and produce results
of such manipulations" and he emphasises the "uninterpreted" nature of
mechanical symbol manipulation, i.e. that the machine is doing it
mindlessly.

Dijkstra[1]: "It is true that the student that has never manipulated
uninterpreted formulae quickly realizes that he is confronted with
something totally unlike anything he has ever seen before. But
fortunately, the rules of manipulation are in this case so few and
simple that very soon thereafter he makes the exciting discovery that
he is beginning to master the use of a tool that, in all its
simplicity, gives him a power that far surpasses his wildest
dreams." [1]


> actively contributing to this perception by teaching this course
> to non-programmers (experimental biologists to be more precise),

Experimental biologists?  Well that's probably harmless.  Mostly
harmless.

> but maybe this idea is not entirely true...  Maybe, to get past
> the most amateurish level, one has to, one way or another, come
> face-to-face with bits, compilers, algorithms, and all the rest
> that real computer scientists learn about in their formal training...
>
> kj

If you're never exposed to that constellation of concepts that
underpins "mechanical symbol manipulation" you are adrift in a sea
("c", ha ha) of abstractions.

However, if you /are/ exposed to the "so few and simple" rules of
manipulation the gates (no pun intended) to the kingdom are thrown
wide.


On Jul 8, 9:10 am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Wed, 08 Jul 2009 12:23:50 +0000, kj wrote:
> > I happen to be very receptive to this point of view.
> [...]
> > There is this persistent idea "out there" that
> > programming is a very accessible skill, like cooking or gardening,
> > anyone can do it, and even profit from it, monetarily or otherwise,
> > etc., and to some extent I am actively contributing to this perception
> > by teaching this course to non-programmers (experimental biologists to
> > be more precise), but maybe this idea is not entirely true...
>
> There is some evidence that 30-60% of people simply cannot learn to
> program, no matter how you teach them:
>
> http://www.codinghorror.com/blog/archives/000635.html
> http://www.cs.mdx.ac.uk/research/PhDArea/saeed/

Thank you! That's exactly the paper that prompted me to write the
article I mentioned. (Now I don't have to go find the link myself.
Win!)

I don't buy it: I believe strongly that any normal person can learn to
program, to manipulate symbols to create formulae that guide the
machine in its uninterpreted symbol manipulation.

I find it significant that in the paper [2] they say, "Formal logical
proofs, and therefore programs ? formal logical proofs that particular
computations are possible, expressed in a formal system called a
programming language ? are utterly meaningless. To write a computer
program you have to come to terms with this, to accept that whatever
you might want the program to mean, the machine will blindly follow
its meaningless rules and come to some meaningless conclusion. In the
test the consistent group showed a pre-acceptance of this fact: they
are capable of seeing mathematical calculation problems in terms of
rules, and can follow those rules wheresoever they may lead. The
inconsistent group, on the other hand, looks for meaning where it is
not."

In other words the people who don't understand computers, don't
understand computers.

I think that "first hump" people can become "second hump" people but
that it requires teaching them the foundations first, not confronting
them with such incredible novelties as "a = b" and saying in effect,
"here you go buddy, sink or swim."

Quoting Dijkstra again [1]: "Before we part, I would like to invite
you to consider the following way of doing justice to computing's
radical novelty in an introductory programming course.

"On the one hand, we teach what looks like the predicate calculus, but
we do it very differently from the philosophers. In order to train the
novice programmer in the manipulation of uninterpreted formulae, we
teach it more as boolean algebra, familiarizing the student with all
algebraic properties of the logical connectives. To further sever the
links to intuition, we rename the values {true, false} of the boolean
domain as {black, white}.

"On the other hand, we teach a simple, clean, imperative programming
language, with a skip and a multiple assignment as basic statements,
with a block structure for local variables, the semicolon as operator
for statement composition, a nice alternative construct, a nice
repetition and, if so desired, a procedure call. To this we add a
minimum of data types, say booleans, integers, characters and strings.
The essential thing is that, for whatever we introduce, the
corresponding semantics is defined by the proof rules that go with
it."

Imagine my surprise: he's saying (with immensely greater brilliance
and eloquence) much what I said in my little article. The major
difference from what he's outlined is that I think the students should
implement the imperative programming language themselves in Forth, but
the gist is the same.


> I'm sympathetic to the idea, but not entirely convinced. Perhaps the
> problem isn't with the students, but with the teachers, and the
> languages:
>
> http://www.csse.monash.edu.au/~damian/papers/PDF/SevenDeadlySins.pdf
>
> (My money is that it's a little of both.)

Hmm, that paper contains some good insights IMO, but I think they're
still missing the big picture, so to speak.

Really I suspect it's a case of "Programming languages considered
harmful."

The core abstractions of [mechanical] computation are just not that
complicated.  You can teach them to anybody in about a half an hour,
drunk. I have.

After that, if they're interested, there is a smooth easy path to
"higher" abstractions: parsing, compiling, tree traversal and
transformation.  (It is said that possession is 9/10s of the law, in
the same vein I would claim parsing is 9/10s of computer programming.)

I am beginning to suspect that concrete static (in the sense of
"standard" language specifications) languages are part of the
problem.  Everyone gets so caught up in programming via languages that
you get, well, people trying to teach "Computer Programming" as if it
were only necessary to grok a language, rather than grokking /symbol
manipulation/ itself.

(Did you read that last paragraph and think, "Well how the heck else
are you supposed to program a computer if not in a computer
language?"?  If so, well, that is kind of my point.)


> > Maybe, to
> > get past the most amateurish level, one has to, one way or another, come
> > face-to-face with bits, compilers, algorithms, and all the rest that
> > real computer scientists learn about in their formal training...
>
> The "No True Scotsman" fallacy.
>
> There's nothing amateurish about building software applications that
> work, with well-designed interfaces and a minimum of bugs, even if you've
> never heard of Turing Machines.
>
> --
> Steven

I beg to differ. I recall a conversation with a co-worker who had
"learned" to program using PHP.  Another co-worker and I were trying
to convince him that there was a good reason to differentiate between
hash tables and arrays. He didn't even know that they were different
"things".

I remember telling him, "between the metal and the desktop there is
nothing but layers of abstraction.  We use different names precisely
because of different behaviours."

He made "well-designed interfaces", but "amateurish" is about the
nicest thing I would have called him.

As for "a minimum of bugs"... sigh. The "minimum of bugs" is zero, if
you derive your "uninterpreted formulae" /correctly/.  Deriving
provably correct "programs" should be what computer science and
computer education are all about (not "java vocational training" as
Alan Kay once decried.)

Again with Dijkstra[3]: "The prime paradigma of the pragmatic designer
is known as "poor man's induction", i.e. he believes in his design as
long as "it works", i.e. until faced with evidence to the contrary.
(He will then "fix the design".) The scientific designer, however,
believes in his design because he understands why it will work under
all circumstances. The transition from pragmatic to scientific design
would indeed be a drastic change within the computer industry."

"Obviously no errors" is the goal to strive for, and I am comfortable
calling anyone an amateur who prefers "no obvious errors."  (Actually
that's a little harsh on the amateurs, "ama" meaning love, "amateur"
is one who does something for love of it.)


On Jul 8, 9:27 am, kj <no.em... at please.post> wrote:
> In <5f0a2722-45eb-468c-b6b2-b7bb80ae5... at q11g2000yqi.googlegroups.com> Simon Forman <sajmik... at gmail.com> writes:
>
> >I'm not kidding. I wrote a (draft) article about this: "Computer
> >Curriculum"http://docs.google.com/View?id=dgwr777r_31g4572gp4
>
> Very cool.
>
> kj

Hey, thank you!


On Jul 8, 9:47 am, Paul Moore <p.f.mo... at gmail.com> wrote:
> 2009/7/8 kj <no.em... at please.post>:
>
> > There is this
> > persistent idea "out there" that programming is a very accessible
<snip>
> > that real computer scientists learn about in their formal training...
>
> Look at it another way. Experimental biologists don't want to program,
> they want to use computers to do experimental biology. It's a tool,
> and they (quite reasonably) don't *care* about robustness,
> portability, etc. Or even about programming, to be honest.

I'd say it's just the opposite: to "use computers to do experimental
biology" they want to instruct that machine to manipulate their
(meaningful to them but meaningless to it) symbols in useful ways.
This is nothing more or less than programming.

The fact that they need to learn all sorts of details of a programming
language to do that is NOT because they can't grok programming. It's
because computer scientists have put too many layers of abstraction on
top of the "pure" symbol manipulation and then forgotten what they
have done.

I have a very nice book "Introduction to Programming and Problem
Solving with Pascal" that I picked up for $0.50 at a used bookstore
not long ago.  It says, right on page 201, in the chapter on "Running,
Debugging, and Testing Programs":

"One of the nice features of programming in a high-level language like
Pascal is that it can be done with almost a total lack of
understanding of what a computer is and how it actually operates.
[...] There is no reason why someone who wants to write a computer
program should have to understand the electronic circuitry of a
computer, any more than someone learning to drive a car should have to
understand how the internal combustion engine works."

I think that's exactly wrong. What you're doing with computers doesn't
change from the bit to the high-level language.  It's all symbol
manipulation according to the same set of rules, all the way up.  The
elaboration becomes involved as you go up but the process does not
change qualitatively.


> In the context of the original question, it's entirely reasonable (in
> my view) to tell this audience "if the code does something weird you
> don't understand, either ignore it and find another way or dig into
> the manuals and experiment if you care". They'd very quickly find a =
> a + b as a less confusing alternative to a += b. (As has been pointed
> out earlier, to some extent a += b is quite an advanced construct -
> after all, it's essentially an optimisation of a = a + b).

On that point I completely agree. The language is getting in the way
of the programming.

> Biologists don't expect me to understand their discipline before I can
> plant seeds in my garden, after all. (And when I do plant seeds, I
> usually get far more surprising results than I could get from a += b
> :-))
>
> Paul.

The discipline of programming is different than biology. It's
incredibly simple yet profound if it's taught as what it is, i.e.
automatic symbol manipulation.

No scientist is a stranger to logic and reasoned argument.  They
shouldn't be strangers to telling their mechanical brains what to
"reason" about.  Learning to program should be /easy/ for someone who
basically already gets it.

Wow, long post.

(Oh, and, er, it's ONTOGENY not Ontology that recapitulates phylogeny.
Heh. My bad.)

[1] "On the cruelty of really teaching computing science"
http://www.cs.utexas.edu/~EWD/transcriptions/EWD10xx/EWD1036.html


[2] "The camel has two humps"
http://www.cs.mdx.ac.uk/research/PhDArea/saeed/paper1.pdf


[3] "Can computing science save the computer industry?"
http://www.cs.utexas.edu/users/EWD/transcriptions/EWD09xx/EWD920.html


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 02:14:18 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 03:14:18 -0300
Subject: Python Error from Apress book
References: <24364269.post@talk.nabble.com>
	<op.uwod1bnzx6zn5v@lepton.softlabbsas.com.ar>
	<4A5345B1.8050306@ieee.org>
	<op.uwpy27kjx6zn5v@lepton.softlabbsas.com.ar>
	<4A54687A.6010004@ieee.org>
Message-ID: <op.uwsd94ipx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 06:35:54 -0300, Dave Angel <davea at ieee.org> escribi?:
> Gabriel Genellina wrote:
>> Jul 2009 09:55:13 -0300, Dave Angel <davea at ieee.org> escribi?:
>>> Gabriel Genellina wrote:
>>>> En Mon, 06 Jul 2009 19:56:40 -0300, matt0177 <matt0177 at gmail.com>  
>>>> escribi?:
>>
>>>>> When I try to run the command as outlined in
>>>>> the book "simple_markup2.py < test_input.txt > test_output.html i  
>>>>> get the
>>>>> following error every time.
>>>>>
>>>>> IOError: [Errno 9] Bad file descriptor
>>
>> I think the error depends on the specific OS version/service pack. But  
>> at least on XP this appears to fix it:
>>
>> http://support.microsoft.com/kb/321788/en-us
>>
> Thanks for the link.  Looking at that one, it indicates that Windows  
> 2000 fixed it in SP4, and XP fixed it in Sp1.  But I'm already running  
> XP SP3, so I wonder if it's something new.

I'm using XP SP3 too. Before applying the registry fix, stdout and stderr  
were working fine, but not stdin. After making the registry change, stdin  
works too.
I didn't notice the issue with stdin until now (I don't use stdin very  
often)

-- 
Gabriel Genellina



From helvinlui at gmail.com  Thu Jul  9 02:27:53 2009
From: helvinlui at gmail.com (Helvin)
Date: Wed, 8 Jul 2009 23:27:53 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
Message-ID: <5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>

On Jul 9, 11:29?am, Robert Kern <robert.k... at gmail.com> wrote:
> On 2009-07-08 18:10, Helvin wrote:
>
> > Thanks for the fast replies! I will look into how to use VTK now.
> > Where would I find VTK's explicit support for PyQt?
>
> Wrapping/Python/vtk/qt4/ in the VTK sources.
>
> > Because I have installed VTK (using its installer) and pyVTK (using
> > its setup.py file), but how do I actually use it in my code? According
> > to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
> > I have tried 'import vtk', but python can't find the vtk module.
>
> Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
> just a library for manipulating VTK files. The VTK Python bindings are part of
> VTK's distribution itself. Exactly how did you install VTK? Did you compile it
> yourself?
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
> ? that is made terrible by our own mad attempt to interpret it as though it had
> ? an underlying truth."
> ? ?-- Umberto Eco

You mean, when I download VTK, the VTK Python bindings come with it?
I downloaded VTK from:http://vtk.org/files/release/5.4/

I downloaded pyVTK from: http://pypi.python.org/pypi/PyVTK/0.4.67
And then installed it by the command 'python setup.py install'
according to: http://cens.ioc.ee/projects/pyvtk/
I understand that this command runs the file called 'setup.py' that
came with the pyVTK download.

Thanks so much for your help! I am very desperate now...

Helvin


From greg at cosc.canterbury.ac.nz  Thu Jul  9 02:29:26 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Thu, 09 Jul 2009 18:29:26 +1200
Subject: tough-to-explain Python
In-Reply-To: <mailman.2847.1247068773.8015.python-list@python.org>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>
	<mailman.2847.1247068773.8015.python-list@python.org>
Message-ID: <7blh0eF23r79rU1@mid.individual.net>

Dave Angel wrote:
> By the time I graduated, I had five six-level languages
                                       ^^^

Are they languages that you have to edit using vi? :-)

-- 
Greg


From morten.aasnes at gmail.com  Thu Jul  9 02:32:56 2009
From: morten.aasnes at gmail.com (Morten Nygaard Aasnes)
Date: 9 Jul 2009 06:32:56 GMT
Subject: Pydev 1.4.7 Released
References: <mailman.2861.1247094510.8015.python-list@python.org>
Message-ID: <7blh8oF2367ioU2@mid.individual.net>

On 2009-07-08, Fabio Zadrozny <fabiofz at gmail.com> wrote:
> Hi All,
>
> Pydev and Pydev Extensions 1.4.7 have been released
>
> Details on Pydev Extensions: http://www.fabioz.com/pydev
> Details on Pydev: http://pydev.sf.net
> Details on its development: http://pydev.blogspot.com

Nice! Will this work in Eclipse 3.5 as well?

-- 
Morten Nygaard ?snes   http://twitter.com/mortenaa   http://identi.ca/mortenaa


From stefan_ml at behnel.de  Thu Jul  9 02:42:06 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Thu, 09 Jul 2009 08:42:06 +0200
Subject: [0, 0, 0, 1, 1, 1, 0] ... remove all 0 values
In-Reply-To: <7xd48bdn73.fsf@ruckus.brouhaha.com>
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<7xd48bdn73.fsf@ruckus.brouhaha.com>
Message-ID: <4a55913f$0$31874$9b4e6d93@newsspool3.arcor-online.net>

Paul Rubin wrote:
> Daniel Austria writes:
>> just one question. How can i remove all 0 values in a list? 
> 
> I prefer:
> 
>    newlist = list(x for x in oldlist if x != 0)
> 
> to the square bracket list comprehension that a few people have
> suggested.  This is because in python 2.x, the listcomp "leaks" its
> index variable into the surrounding scope, but the generator
> expression above doesn't.

As you indicated, that's been fixed in Py3, though. So if your code works
in Py3.x, you can be somewhat sure that the leak doesn't have side effects.
Plus, it's pretty easy to ignore those leaks as long as you use a suitable
name for the loop variable.

Also note that the performance characteristics may not be identical in both
cases, depending on where you run your code. Cython, for example, will
write a list comprehension out as a rather straight C loop, but when we
implement generator expressions in Cython, it may have to get turned into a
generator function instead of a loop, so that you'd get a much larger
overhead than for the plain list comprehension (although in the simple case
above it would likely get optimised away).

CPython shows a similar difference:

$ python3.1 -m timeit '[x for x in range(1000) if x]'
10000 loops, best of 3: 170 usec per loop
$ python3.1 -m timeit -s 'r=[i%2 for i in range(2000)]' \
				'[x for x in r if x]'
1000 loops, best of 3: 222 usec per loop

$ python3.1 -m timeit 'list(x for x in range(1000) if x)'
1000 loops, best of 3: 227 usec per loop
$ python3.1 -m timeit -s 'r=[i%2 for i in range(2000)]' \
				'list(x for x in r if x)'
1000 loops, best of 3: 280 usec per loop


Not that I'd consider those numbers worth bothering...

Stefan


From Lacrima.Maxim at gmail.com  Thu Jul  9 02:50:37 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Wed, 8 Jul 2009 23:50:37 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
Message-ID: <379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>

On Jul 8, 10:54?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Lacrima <Lacrima.Ma... at gmail.com> (L) wrote:
> >L> Hello!
> >L> I have just started using Emacs to write python scripts.
> >L> I installed python-mode.el
> >L> Then I just tried this code:
> >L> print 'hello world'
> >L> When I press C-c RET, new blank window is opened and emacs says:
> >L> (Shell command succeeded with no output)
> >L> So where is my 'hello world'?
> >L> When I do C-c C-c, it prints 'hello world' successfully.
> >L> Why in the first case I get no output?
>
> Can you check in the buffer where you have the python code what command
> C-c RET is bound to?
> With C-h k C-c RET
>
> Shell command succeeded with no output suggests that is has a different
> binding than the standard one in python-mode.
>
> Did you happen to name your file 'test' or 'test.py?
>
> C-c RET does an import and 'import test' imports a standard module test.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

Hi, Piet!

Thanks for your reply!
My file name is 'trains.py'.
When I do C-h k C-c RET, it shows me help from manual: "C-c RET runs
the command py-execute-import-or-reload
   which is an interactive Lisp function in `python-mode'..." and so
on.

And still when I do C-c RET, I receive "(Shell command succeeded with
no output)"

Any more help would be really appreciated, because I am newbie with
Emacs.

With regards, Max


From reddy.mrp at gmail.com  Thu Jul  9 03:17:52 2009
From: reddy.mrp at gmail.com (m.reddy prasad reddy)
Date: Thu, 9 Jul 2009 12:47:52 +0530
Subject: can i write a assemly language programs in python
Message-ID: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>

can any one tell me how to write assembly language programs in python...if
no is there any other way to write the programs in python

Reddi prasad reddy
ph.no:09958083797
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/ac092206/attachment-0001.html>

From futurebase at gmx.at  Thu Jul  9 03:22:43 2009
From: futurebase at gmx.at (Daniel Austria)
Date: Thu, 9 Jul 2009 00:22:43 -0700 (PDT)
Subject: ... remove all 0 values
References: <29df6e77-0d5b-4da1-8ded-89c5840b9680@c36g2000yqn.googlegroups.com>
	<7xd48bdn73.fsf@ruckus.brouhaha.com>
	<4a55913f$0$31874$9b4e6d93@newsspool3.arcor-online.net>
Message-ID: <4dcaab15-2d2d-4d7c-bd93-5e7f931cb369@j32g2000yqh.googlegroups.com>

Thanks a lot for your advices,

i decided to use the filter() method to sort out the 0.
i can ?t use the sum() function cause i need the list afterwards ....


best,
Dan


From reddy.mrp at gmail.com  Thu Jul  9 03:25:17 2009
From: reddy.mrp at gmail.com (m.reddy prasad reddy)
Date: Thu, 9 Jul 2009 12:55:17 +0530
Subject: i need immediate help from u
Message-ID: <a97ce0940907090025v7734dd5braa035ecbe92633f6@mail.gmail.com>

i m new this community .;
can any one send me the solution for writing the assembly language programs
in python
my mail ID:redd.mrp at gmail.com <ID%3Aredd.mrp at gmail.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/c440cdb1/attachment-0001.html>

From __peter__ at web.de  Thu Jul  9 03:29:04 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 09 Jul 2009 09:29:04 +0200
Subject: regex help
References: <c6c69644-5db1-47a5-acd3-854384a43dd7@h8g2000yqm.googlegroups.com>
Message-ID: <h34680$kme$02$1@news.t-online.com>

David wrote:

> <td>&nbsp;</td>
> 
> <td width="1%" class=key>Open:
> </td>
> <td width="1%" class=val>5.50
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>Mkt Cap:
> </td>
> <td width="1%" class=val>6.92M
> </td>
> <td>&nbsp;</td>
> <td width="1%" class=key>P/E:
> </td>
> <td width="1%" class=val>21.99
> </td>
> 
> 
> I want to extract the open, mkt cap and P/E values - but apart from
> doing loads of indivdual REs which I think would look messy, I can't
> think of a better and neater looking way. Any ideas?

>>> from BeautifulSoup import BeautifulSoup
>>> bs = BeautifulSoup("""<td>&nbsp;</td>
...
... <td width="1%" class=key>Open:
... </td>
... <td width="1%" class=val>5.50
... </td>
... <td>&nbsp;</td>
... <td width="1%" class=key>Mkt Cap:
... </td>
... <td width="1%" class=val>6.92M
... </td>
... <td>&nbsp;</td>
... <td width="1%" class=key>P/E:
... </td>
... <td width="1%" class=val>21.99
... </td>
... """)
>>> for key in bs.findAll(attrs={"class": "key"}):
...     value = key.findNext(attrs={"class": "val"})
...     print key.string.strip(), "-->", value.string.strip()
...
Open: --> 5.50
Mkt Cap: --> 6.92M
P/E: --> 21.99




From clp2 at rebertia.com  Thu Jul  9 03:29:33 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 00:29:33 -0700
Subject: i need immediate help from u
In-Reply-To: <a97ce0940907090025v7734dd5braa035ecbe92633f6@mail.gmail.com>
References: <a97ce0940907090025v7734dd5braa035ecbe92633f6@mail.gmail.com>
Message-ID: <50697b2c0907090029n66002f7cy68a5c51082c2b232@mail.gmail.com>

On Thu, Jul 9, 2009 at 12:25 AM, m.reddy prasad
reddy<reddy.mrp at gmail.com> wrote:
> i m new this community .;
> can any one send me the solution for writing the assembly language programs
> in python
> my mail ID:redd.mrp at gmail.com

Please read http://catb.org/esr/faqs/smart-questions.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From CHausberger at gmx.de  Thu Jul  9 03:41:20 2009
From: CHausberger at gmx.de (Claus Hausberger)
Date: Thu, 09 Jul 2009 09:41:20 +0200
Subject: Problem reading file with umlauts
In-Reply-To: <4A53B2B4.9090409@mrabarnett.plus.com>
References: <20090707135949.100950@gmx.net> <4A53643C.4020905@xs4all.nl>
	<20090707190046.152740@gmx.net> <4A53B2B4.9090409@mrabarnett.plus.com>
Message-ID: <20090709074120.198030@gmx.net>

Thanks a lot. I will try that on the weekend.

Claus

> Claus Hausberger wrote:
> > Thanks a lot. Now I am one step further but I get another strange error:
> > 
> > Traceback (most recent call last):
> >   File "./read.py", line 12, in <module>
> >     of.write(text)
> > UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in
> position 0: ordinal not in range(128)
> > 
> > according to google ufeff has something to do with byte order.
> > 
> > I use an Linux system, maybe this helps to find the error.
> > 
> 'text' contains Unicode, but you're writing it to a file that's not
> opened for Unicode. Either open the output file for Unicode:
> 
>      of = codecs.open("umlaut-out.txt", "w", encoding="latin1")
> 
> or encode the text before writing:
> 
>      text = text.encode("latin1")
> 
> (I'm assuming you want the output file to be in Latin1.)
> 
> > 
> >> Claus Hausberger wrote:
> >>
> >>> I have a text file with is encoding in Latin1 (ISO-8859-1). I can't
> >>> change that as I do not create those files myself. I have to read
> >>> those files and convert the umlauts like ? to stuff like &oumol; as
> >>> the text files should become html files.
> >> umlaut-in.txt:
> >> ----
> >> This file is contains data in the unicode
> >> character set and is encoded with utf-8.
> >> Viele R?hre. Macht spa?!  Ts?sch!
> >>
> >>
> >> umlaut-in.txt hexdump:
> >> ----
> >> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is
> con
> >> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in
> th
> >> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0A 63 68 61 72 61 e
> unicode..chara
> >> 000030: 63 74 65 72 20 73 65 74  20 61 6E 64 20 69 73 20 cter set and
> is
> >> 000040: 65 6E 63 6F 64 65 64 20  77 69 74 68 20 75 74 66 encoded with
> utf
> >> 000050: 2D 38 2E 0D 0A 56 69 65  6C 65 20 52 C3 B6 68 72 -8...Viele
> R..hr
> >> 000060: 65 2E 20 4D 61 63 68 74  20 73 70 61 C3 9F 21 20 e. Macht
> spa..!
> >> 000070: 20 54 73 C3 BC 73 63 68  21 0D 0A 00 00 00 00 00 
> Ts..sch!.......
> >>
> >>
> >> umlaut.py:
> >> ----
> >> # -*- coding: utf-8 -*-
> >> import codecs
> >> text=codecs.open("umlaut-in.txt",encoding="utf-8").read()
> >> text=text.replace(u"?",u"oe")
> >> text=text.replace(u"?",u"ss")
> >> text=text.replace(u"?",u"ue")
> >> of=open("umlaut-out.txt","w")
> >> of.write(text)
> >> of.close()
> >>
> >>
> >> umlaut-out.txt:
> >> ----
> >> This file is contains data in the unicode
> >> character set and is encoded with utf-8.
> >> Viele Roehre. Macht spass!  Tsuesch!
> >>
> >>
> >> umlaut-out.txt hexdump:
> >> ----
> >> 000000: 54 68 69 73 20 66 69 6C  65 20 69 73 20 63 6F 6E This file is
> con
> >> 000010: 74 61 69 6E 73 20 64 61  74 61 20 69 6E 20 74 68 tains data in
> th
> >> 000020: 65 20 75 6E 69 63 6F 64  65 0D 0D 0A 63 68 61 72 e
> unicode...char
> >> 000030: 61 63 74 65 72 20 73 65  74 20 61 6E 64 20 69 73 acter set and
> is
> >> 000040: 20 65 6E 63 6F 64 65 64  20 77 69 74 68 20 75 74  encoded with
> ut
> >> 000050: 66 2D 38 2E 0D 0D 0A 56  69 65 6C 65 20 52 6F 65 f-8....Viele
> Roe
> >> 000060: 68 72 65 2E 20 4D 61 63  68 74 20 73 70 61 73 73 hre. Macht
> spass
> >> 000070: 21 20 20 54 73 75 65 73  63 68 21 0D 0D 0A 00 00 ! 
> Tsuesch!.....
> >>
> >>
> >>
> >>
> >>
> >> -- 
> >> "The ability of the OSS process to collect and harness
> >> the collective IQ of thousands of individuals across
> >> the Internet is simply amazing." - Vinod Valloppillil
> >> http://www.catb.org/~esr/halloween/halloween4.html
> > 
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list

-- 
Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
f?r nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02


From rajat.dudeja at gmail.com  Thu Jul  9 03:55:37 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Thu, 9 Jul 2009 00:55:37 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz> 
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com> 
	<mailman.2827.1247039136.8015.python-list@python.org>
Message-ID: <a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>

On Jul 8, 12:45?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Rajat wrote:
> > On Jul 8, 4:57 am, Lawrence D'Oliveiro <l... at geek-
> > central.gen.new_zealand> wrote:
> >> In message <mailman.2795.1246997268.8015.python-l... at python.org>, Christian
>
> >> Heimes wrote:
> >>> By the way most operating systems don't lock a file when it's opened for
> >>> reading or writing or even executed.
> >> The general conclusion seems to be that mandatory locking is more trouble
> >> than it's worth.
>
> > My OS is a windows XP sp3. All I'm trying to achieve is to close an
> > application ( which could be a notepad, a wordpad or some other text
> > editor) that have opened my file. Once the file is closed I can easily
> > delete that file.
>
> > I guess, if file is opened by one of that application, the file must
> > be locked and so is the reason I cannot delete the file.
>
> I assume that your real requirement is: I can't open/close/delete
> this file; it must be locked by something else; what is that
> something else?
>
> The simplest thing is probably to run sysinternals' handle util:
>
> ?http://technet.microsoft.com/en-us/sysinternals/bb896655.aspx
>
> and use the subprocess module to parse the output.
> That will give you the pid, and you can then use, eg, psutil:
>
> ?http://code.google.com/p/psutil/
>
> to get the details of the process.
>
> TJG- Hide quoted text -
>
> - Show quoted text -

I've used the Handle.exe and got the following results:

------------------------------------------------------------------------------
notepad.exe pid: 3540 COMP\rajatd
    C: File  (RW-)   C:\Documents and Settings\rajatd\Desktop
   10: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   44: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   7C: Section       \BaseNamedObjects\ShimSharedMemory

------------------------------------------------------------------------------
wordpad.exe pid: 2212 COMP\rajatd
   1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   74: Section       \BaseNamedObjects\ShimSharedMemory
   F8: Section       \BaseNamedObjects
\CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
  170: Section       \BaseNamedObjects\RotHintTable
  184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents

I've also parsed this output for the PIDS. But no where in the result
I got to know what file has been associated with a PID.

Does for this I need to use pustil?


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 03:57:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 04:57:15 -0300
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
Message-ID: <op.uwsi1pv3x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 23:19:25 -0300, kj <no.email at please.post> escribi?:

> In <mailman.2700.1246895025.8015.python-list at python.org> Tim Rowe  
> <digitig at gmail.com> writes:
>
>> 2009/7/4 kj <no.email at please.post>:
>
>>> Precisely. =A0As I've stated elsewhere, this is an internal helper
>>> function, to be called only a few times under very well-specified
>>> conditions. =A0The assert statements checks that these conditions
>>> are as intended. =A0I.e. they are checks against the module writer's
>>> programming errors.
>
>> Good for you. I'm convinced that you have used the assertion
>> appropriately, and the fact that so many here are unable to see that
>> looks to me like a good case for teaching the right use of assertions.
>> For what it's worth, I read assertions at the beginning of a procedure
>> as part of the specification of the procedure, and I use them there in
>> order to document the procedure. An assertion in that position is for
>> me a statement to the user of the procedure "it's your responsibility
>> to make sure that you never call this procedure in such a way as to
>> violate these conditions". They're part of a contract, as somebody
>> (maybe you) pointed out.
>
>> As somebody who works in the safety-critical domain, it's refreshing
>> to see somebody teaching students to think about the circumstances in
>> which a procedure can legitimately be called. The hostility you've
>> received to that idea is saddening, and indicative of why there's so
>> much buggy software out there.
>
> Thanks for the encouragement.
>
> When I teach programming, the students are scientists.  For the
> stuff they do, correctness of the code trumps everything else.  I
> teach them to view assertions as way of translating their assumptions
> into code.  And by this I mean not only assumptions about the
> correctness of their code (the typical scope of assertions), but
> also, more broadly, assumptions about the data that they are dealing
> with (which often comes from external sources with abysmal quality
> control).

Nobody says you shouldn't check your data. Only that "assert" is not the  
right way to do that. Ok, it's easier to write:

   assert x>0 and y>0 and x<y

instead of:

   if not (x>0 and y>0 and x<y):
     raise ValueError, "x=%r y=%r" % (x,y)

but the assert statement is completely ignored if your script is run with  
the -O option, and then no check is done.
assert should be used only to verify internal correctness only - to detect  
wrong assumptions in the *code* itself. Once you're confident the code is  
OK, you may turn off assertions (and improve program speed). But you must  
*always* validate input data no matter what - so assert is not the right  
tool.

Even worse, never DO anything inside an assertion - it won't be done in  
the optimized version. This method becomes almost empty when assertions  
are removed (not the intended behavior!):

def process_all(self):
     for item in self.items:
       assert self.process(item)

> My scientific code is jam-packed with assertions.  I can't count
> the number of times that one such lowly assertion saved me from a
> silent but potentially disastrous bug.  And yes I find it distressing
> that so so few programmers in my line of work use assertions at
> all.

I'm just saying that some of those assertions probably should be real "if  
... raise" statements instead - not that you remove the checks. You may  
use this short function, if you prefer:

def fassert(condition, message='', exc_type=AssertionError):
   if not condition:
     raise exc_type(message)

-- 
Gabriel Genellina



From __peter__ at web.de  Thu Jul  9 03:59:54 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 09 Jul 2009 09:59:54 +0200
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
Message-ID: <h3481q$d95$00$1@news.t-online.com>

Paul Simon wrote:

> "Chris Rebert" <clp2 at rebertia.com> wrote in message
> news:mailman.2863.1247095339.8015.python-list at python.org...
> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>> I have the "tkinter" problem and need some assistance to straighten it
>> out.
>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>> >"step
>> 1" and cannot import "_tkinter." I do not have that file on my computer,
>> but
>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>> This python stuff is great, but the documentation frequently
>> feels like it is just a bit out of my grasp. I realize that all of this
>> is free but I understand the instructions on the web page to repair only
>> to the
>> point of confusion. I'm not an expert. How do I modify my python
>> configuration? Is there a file that needs to be edited? Which setup.py
>> file
>> do I use? Make? or python setup.py build and python setup.py install?
>> Thanks. I appreciate your help.
> 
> - How did you install Python?
> - What Linux distro are you using?
> 
> Cheers,
> Chris
> http://blog.rebertia.com
> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
> exactly how I installed Python.  Originally I had installed 2.5 from RPM
> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
> something from python.org and installed.  Not sure if it was tarball or
> zip file.

Zip or tar doesn't matter, you are installing "from source".

Python has to find the necessary include files for tcl/tk. These are in 
separate packages that you have to install before you invoke Python's 
configure script.

I don't know what they are called on your system -- look for tk-dev.rpm, 
tcl-dev.rpm or similar.

You may run into the same problem with other modules like readline.

Peter



From mukherjee.tanmoy at gmail.com  Thu Jul  9 04:18:30 2009
From: mukherjee.tanmoy at gmail.com (Tanmoy)
Date: Thu, 9 Jul 2009 13:48:30 +0530
Subject: Hello
Message-ID: <c140049d0907090118v1307828dmfbe42bd2bc113050@mail.gmail.com>

Hi ...
    I have been trying to set this 2-D array of this sort.

  0 10 20 ........... 1000
  1 11 21...............

   1000


Here is the code i tried ...

arr=[]
for i in range(0,1010,10):
    arr.append([])
    for j in range(0,1001,1):
          arr[i].append(i+j)

print arr

I am getting the following error
 list index out of range

Please let me know where am i getting wrong.

Sincerely
tank
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/ae1f5689/attachment-0001.html>

From gagsl-py2 at yahoo.com.ar  Thu Jul  9 04:19:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 05:19:37 -0300
Subject: Problem with list of dicts and copying
References: <5700df6b0907081009p5ec4167cqec36e915e0f6c4@mail.gmail.com>
Message-ID: <op.uwsj2zqex6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 14:09:43 -0300, Cameron Pulsford  
<cameron.pulsford at gmail.com> escribi?:

> I'm representing the board as a dictionary, where the keys are
> (x, y) positions, and the values are candidates. So my program goes along
> picking numbers from the list of candidates and then propagating the
> constraints. [...]Basically my boards list should be copies of good  
> boards, and when I need to
> refresh the current board, I want to pull off a copy of the correct one. 
> [...] this isn't happening. I am always modifying the same board.

You have a dictionary whose values are lists, ok? The copy() method  
doesn't make a copy of those lists - only of the dictionary itself. Try  
using the deepcopy function in the copy module:
http://docs.python.org/library/copy.html

-- 
Gabriel Genellina



From mail at timgolden.me.uk  Thu Jul  9 04:21:17 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 09 Jul 2009 09:21:17 +0100
Subject: Check file is locked?
In-Reply-To: <a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
Message-ID: <4A55A87D.6060802@timgolden.me.uk>

Rajat wrote:
> I've used the Handle.exe and got the following results:
> 
> ------------------------------------------------------------------------------
> notepad.exe pid: 3540 COMP\rajatd
>     C: File  (RW-)   C:\Documents and Settings\rajatd\Desktop
>    10: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    44: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    7C: Section       \BaseNamedObjects\ShimSharedMemory
> 
> ------------------------------------------------------------------------------
> wordpad.exe pid: 2212 COMP\rajatd
>    1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    74: Section       \BaseNamedObjects\ShimSharedMemory
>    F8: Section       \BaseNamedObjects
> \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
>   170: Section       \BaseNamedObjects\RotHintTable
>   184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
> 
> I've also parsed this output for the PIDS. But no where in the result
> I got to know what file has been associated with a PID.
> 
> Does for this I need to use pustil?


Well unless I'm missing your point considerably, the output tells
you all you need to know: notepad.exe (pid 3540) has some kind
of handle open on the desktop, the common controls DLL and an
area of shared memory. As has been pointed out elsewhere, notepad
doesn't hold the file open which it's editing: it opens it, reads
the contents, and closes it again. 

For demonstration purposes:

<code>
import os, sys
import subprocess

f = open (sys.executable)
subprocess.call (["handle", sys.executable])
f.close ()

</code>


TJG


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 04:23:51 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 05:23:51 -0300
Subject: windows command-line
References: <376017.28322.qm@web30601.mail.mud.yahoo.com>
	<h32kne$s0l$1@ger.gmane.org>
Message-ID: <op.uwsj91v2x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 08 Jul 2009 14:23:54 -0300, Emile van Sebille <emile at fenx.com>  
escribi?:
> On 7/8/2009 10:07 AM Lucas Junqueira said...

>> Hi, I'd like to run a simple windows command-line program from within  
>> my python script and agt all the returt it generates. Is this possible?  
>> How can I do it?
>
> Depending on python version, look into subprocess, commands or os.pipe  
> and related.

commands is Unix only, and os.pipe by itself doesn't solve the problem -  
so we are left with subprocess, and that would be my reccomendation too.

-- 
Gabriel Genellina



From dickinsm at gmail.com  Thu Jul  9 04:29:02 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Thu, 9 Jul 2009 01:29:02 -0700 (PDT)
Subject: python3 fail to start
References: <788ec223-9894-4168-b1f8-758cd51a47ad@r16g2000vbn.googlegroups.com>
Message-ID: <06650e06-5073-4420-972c-1add7c9bbbd6@h8g2000yqm.googlegroups.com>

On Jun 30, 3:43?pm, ts <thaisi... at gmail.com> wrote:
> i just install the python 3.1 dmg onto my mac. when i run python3, it
> fail with :
>
> Fatal Python error: Py_Initialize: can't initialize sys standard
> streamsLookupError: unknown encoding:
> Abort trap
>
> couldnt understand the problem. anyone can help?

Any chance you could give us some feedback about your system?  The
Python devs are working to fix the problem:

http://bugs.python.org/issue6393

but it would be really helpful to know:

- what version of OS X you're using
- what output you get when you type 'locale' at a Terminal prompt
- what the International settings are in your Terminal preferences
  (Terminal preferences -> Settings -> Advanced tab):  what's the
  setting for the character encoding, and do you have the 'Set LANG
  environment variable at startup' checkbox checked?

I managed to reproduce the crash by starting python3 (again
at a Terminal prompt) with:

LANG=UTF-8 python3

So I suspect that your locale settings are part of the problem.
As a temporary workaround, something like

LANG=en_US.UTF-8 python3

might work.  (Substitute whatever language setting is appropriate
for you in place of en_US.)

Thanks!

Mark


From python at mrabarnett.plus.com  Thu Jul  9 04:41:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 09 Jul 2009 09:41:42 +0100
Subject: Hello
In-Reply-To: <c140049d0907090118v1307828dmfbe42bd2bc113050@mail.gmail.com>
References: <c140049d0907090118v1307828dmfbe42bd2bc113050@mail.gmail.com>
Message-ID: <4A55AD46.8010407@mrabarnett.plus.com>

Tanmoy wrote:
T Hi ...
>     I have been trying to set this 2-D array of this sort.
> 
>   0 10 20 ........... 1000
>   1 11 21...............
>   
>    1000
> 
> 
> Here is the code i tried ...
> 
> arr=[]
> for i in range(0,1010,10):
>     arr.append([])
>     for j in range(0,1001,1):
>           arr[i].append(i+j)
>          
> print arr
> 
> I am getting the following error
>  list index out of range
> 
> Please let me know where am i getting wrong.
> 
The value of 'i' goes 0, 10, ..., etc.

When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
problem.

When i==10 you append another empty list to arr, so arr[i] is arr[10].
Index error because there's no arr[10], only arr[0] and arr[1].


From gagsl-py2 at yahoo.com.ar  Thu Jul  9 05:03:21 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 06:03:21 -0300
Subject: can i write a assemly language programs in python
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <op.uwsl3vobx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 09 Jul 2009 04:17:52 -0300, m.reddy prasad reddy  
<reddy.mrp at gmail.com> escribi?:

> can any one tell me how to write assembly language programs in  
> python...if
> no is there any other way to write the programs in python

You write Python programs using Python, not assembly.

Perhaps if you provide more info on what you want to do, someone can  
suggest a different way...

-- 
Gabriel Genellina



From andy2.0 at gmail.com  Thu Jul  9 05:26:10 2009
From: andy2.0 at gmail.com (Andy Clegg)
Date: Thu, 9 Jul 2009 02:26:10 -0700 (PDT)
Subject: subprocess + python-daemon - bug/problem?
Message-ID: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>

Hi all,

I'm trying to daemonize a python program, and occasionally have it run
subprocesses, however I'm running into a nasty error, as follows:

"File "/users/rsg/ancl/devcocast/devcocast-svn/scripts/DaemonSpawnTes
t.py", line 5, in <module>
    subprocess.Popen('echo 1').wait()
  File "/usr/lib64/python2.5/subprocess.py", line 594, in __init__
    errread, errwrite)
  File "/usr/lib64/python2.5/subprocess.py", line 1089, in _execute_ch
ild
    os.waitpid(self.pid, 0)
OSError: [Errno 10] No child processes"

The minimal testcase showing this problem is as follows:

"import daemon
import subprocess

daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
subprocess.Popen('echo 1').wait()"

So there is no threading going on (I've found some bugs relating to
subprocess and threading). I'm using Fedora 10, Python 2.5.2, and
python-daemon 1.4.6 from here http://pypi.python.org/pypi/python-daemon/
.

If anyone can shed some light on the situation, I'd be extremely
grateful!

Yours,

Andy


From user at example.net  Thu Jul  9 05:36:13 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 11:36:13 +0200
Subject: older pythons
Message-ID: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>

hi everybody.

i have a certain set of old python scripts and data used by said scripts 
which were written using python 2.3

in particular i used some features which were later modified or 
deprecated by the language newer versions (e.g.: cmp(), print as 
keyword, and such...)

for reasons i find hard to explain briefly, it is unfeasible at the 
moment to modify scripts and data to adapt to the changes

now: i ask if it is possible to have different versions of python 
installed on my system (linux debian) so that i can continue to use 
python 2.3 (as "python" from the shell) but i can also use - say - 
python 3.1 (maybe as "python3.1" from the shell)

if yes: is there a known recommended way to do so?

thanks a lot

bye


From andy2.0 at gmail.com  Thu Jul  9 05:42:54 2009
From: andy2.0 at gmail.com (Andy Clegg)
Date: Thu, 9 Jul 2009 02:42:54 -0700 (PDT)
Subject: subprocess + python-daemon - bug/problem?
References: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>
Message-ID: <828acd8d-a9bd-4506-b695-e537af4587d8@l31g2000yqb.googlegroups.com>

My apologies, the python code should have been:

"import daemon
import subprocess

daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
subprocess.Popen(['echo','1']).wait()"

However the error remains the same.

Yours,

Andy

On Jul 9, 10:26?am, Andy  Clegg <andy... at gmail.com> wrote:
> Hi all,
>
> I'm trying to daemonize a python program, and occasionally have it run
> subprocesses, however I'm running into a nasty error, as follows:
>
> "File "/users/rsg/ancl/devcocast/devcocast-svn/scripts/DaemonSpawnTes
> t.py", line 5, in <module>
> ? ? subprocess.Popen('echo 1').wait()
> ? File "/usr/lib64/python2.5/subprocess.py", line 594, in __init__
> ? ? errread, errwrite)
> ? File "/usr/lib64/python2.5/subprocess.py", line 1089, in _execute_ch
> ild
> ? ? os.waitpid(self.pid, 0)
> OSError: [Errno 10] No child processes"
>
> The minimal testcase showing this problem is as follows:
>
> "import daemon
> import subprocess
>
> daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
> subprocess.Popen('echo 1').wait()"
>
> So there is no threading going on (I've found some bugs relating to
> subprocess and threading). I'm using Fedora 10, Python 2.5.2, and
> python-daemon 1.4.6 from herehttp://pypi.python.org/pypi/python-daemon/
> .
>
> If anyone can shed some light on the situation, I'd be extremely
> grateful!
>
> Yours,
>
> Andy



From adrian.dziubek at gmail.com  Thu Jul  9 05:53:40 2009
From: adrian.dziubek at gmail.com (Adrian Dziubek)
Date: Thu, 9 Jul 2009 02:53:40 -0700 (PDT)
Subject: older pythons
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
Message-ID: <d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>

The recommended Debian way is update-alternatives. I find it a bit
unintuitive, so I have to read through the documentation every time I
use it, but it should be able link a chosen version of python to /usr/
bin/python. I don't know if it's set up by default, I have only one
version installed.
--
Adrian


From rajat.dudeja at gmail.com  Thu Jul  9 06:03:00 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Thu, 9 Jul 2009 03:03:00 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz> 
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com> 
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
Message-ID: <a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>

On Jul 9, 1:21?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Rajat wrote:
> > I've used the Handle.exe and got the following results:
>
> > ---------------------------------------------------------------------------?---
> > notepad.exe pid: 3540 COMP\rajatd
> > ? ? C: File ?(RW-) ? C:\Documents and Settings\rajatd\Desktop
> > ? ?10: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?44: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?7C: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
>
> > ---------------------------------------------------------------------------?---
> > wordpad.exe pid: 2212 COMP\rajatd
> > ? ?1C: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?40: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?74: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
> > ? ?F8: Section ? ? ? \BaseNamedObjects
> > \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
> > ? 170: Section ? ? ? \BaseNamedObjects\RotHintTable
> > ? 184: File ?(RW-) ? C:\Documents and Settings\rajatd\My Documents
>
> > I've also parsed this output for the PIDS. But no where in the result
> > I got to know what file has been associated with a PID.
>
> > Does for this I need to use pustil?
>
> Well unless I'm missing your point considerably, the output tells
> you all you need to know: notepad.exe (pid 3540) has some kind
> of handle open on the desktop, the common controls DLL and an
> area of shared memory. As has been pointed out elsewhere, notepad
> doesn't hold the file open which it's editing: it opens it, reads
> the contents, and closes it again.
>
> For demonstration purposes:
>
> <code>
> import os, sys
> import subprocess
>
> f = open (sys.executable)
> subprocess.call (["handle", sys.executable])
> f.close ()
>
> </code>
>
> TJG- Hide quoted text -
>
> - Show quoted text -

The Notepad process information is fine here. However, with wordpad
the results are not much differentiating:

------------------------------------------------------------------------------
wordpad.exe pid: 2832 COMP\rajatd
   1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   74: Section       \BaseNamedObjects\ShimSharedMemory
   F8: Section       \BaseNamedObjects
\CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
  170: Section       \BaseNamedObjects\RotHintTable
  184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
------------------------------------------------------------------------------
wordpad.exe pid: 844 COMP\rajatd
   1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
   74: Section       \BaseNamedObjects\ShimSharedMemory
   F8: Section       \BaseNamedObjects
\CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
  170: Section       \BaseNamedObjects\RotHintTable
  184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents

Both the wordpad applications opened 2 totally different files kept at
different locations on the system.

So, on the basis of above results one can not say out of these 2
wordpad apps which is the right one that could be closed. The only
different thing among the two is the PIDs.


From luislupeXXX at gmailXXX.com  Thu Jul  9 06:06:16 2009
From: luislupeXXX at gmailXXX.com (Luis P. Mendes)
Date: 09 Jul 2009 10:06:16 GMT
Subject: Psyco 64 bits
Message-ID: <4a55c118$0$48237$14726298@news.sunsite.dk>

Hi,

I used Psyco to speed up my Python code.
Due to the great amount of data I have to proccess, I moved my Linux 
system to a 64 bits version with more RAM.

It seems that Psyco cannot be used in such platforms.
Or is there another version of Psyco for 64 bits platform?

I googled and arrived to PyPy.  But I don't know how to use it.
With psyco, I used to include two statements roughly at the beginning of 
the script:
import psyco
psyco.full()

With PyPy, is there a similar way to try to speed up my script?


Luis


From tkermode at gmail.com  Thu Jul  9 06:13:43 2009
From: tkermode at gmail.com (Tom Kermode)
Date: Thu, 9 Jul 2009 11:13:43 +0100
Subject: can i write a assemly language programs in python
In-Reply-To: <op.uwsl3vobx6zn5v@lepton.softlabbsas.com.ar>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
	<op.uwsl3vobx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <da7092380907090313v10d72af9k5dbfbb9507129eb5@mail.gmail.com>

I wonder if the OP is trying to find out whether python programmes can
be compiled and run as stand alone executables.

(I know assembly and machine code are not the same, but it might be
what they're after.)

On windows you can use http://www.py2exe.org/ to bundle python
programs into stand alone executables. They're not compiled, but your
code and all the modules it relies on are brought together, meaning
you can deliver a single exe than can be run like any other windows
program.

Maybe that helps...

2009/7/9 Gabriel Genellina <gagsl-py2 at yahoo.com.ar>:
> En Thu, 09 Jul 2009 04:17:52 -0300, m.reddy prasad reddy
> <reddy.mrp at gmail.com> escribi?:
>
>> can any one tell me how to write assembly language programs in python...if
>> no is there any other way to write the programs in python
>
> You write Python programs using Python, not assembly.
>
> Perhaps if you provide more info on what you want to do, someone can suggest
> a different way...
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.kiloday.com
http://www.fourstopspast.com


From mail at timgolden.me.uk  Thu Jul  9 06:21:51 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 09 Jul 2009 11:21:51 +0100
Subject: Check file is locked?
In-Reply-To: <a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
Message-ID: <4A55C4BF.6080200@timgolden.me.uk>

Rajat wrote:
> The Notepad process information is fine here. However, with wordpad
> the results are not much differentiating:
> 
> ------------------------------------------------------------------------------
> wordpad.exe pid: 2832 COMP\rajatd
>    1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    74: Section       \BaseNamedObjects\ShimSharedMemory
>    F8: Section       \BaseNamedObjects
> \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
>   170: Section       \BaseNamedObjects\RotHintTable
>   184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
> ------------------------------------------------------------------------------
> wordpad.exe pid: 844 COMP\rajatd
>    1C: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    40: File  (RW-)   C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
>    74: Section       \BaseNamedObjects\ShimSharedMemory
>    F8: Section       \BaseNamedObjects
> \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
>   170: Section       \BaseNamedObjects\RotHintTable
>   184: File  (RW-)   C:\Documents and Settings\rajatd\My Documents
> 
> Both the wordpad applications opened 2 totally different files kept at
> different locations on the system.
> 
> So, on the basis of above results one can not say out of these 2
> wordpad apps which is the right one that could be closed. The only
> different thing among the two is the PIDs.


Rajat: are you trying to find out which app is holding a file open?

If so -- run handle.exe *for that filename*, as my code does:

handle.exe <filename>

This will only show which apps are holding that file. I suspect
you're running handle.exe on its own which will show everything
which is holding handles on anything.

1) Use wordpad.exe to open c:\temp\blah.txt

2) Run "handle.exe c:\temp\blah.txt"

3) Observe (at least on my Win XP Sp3 machine) that *no* process
has a handle open on c:\temp\blah.txt, including wordpad, which
presumably opens the file, reads it, and closes it again.


The items you're seeing above are system-level handles which
wordpad is holding for reasons of its own, but none of them
is a user filename.

TJG


From mukherjee.tanmoy at gmail.com  Thu Jul  9 06:31:56 2009
From: mukherjee.tanmoy at gmail.com (Tanmoy)
Date: Thu, 9 Jul 2009 16:01:56 +0530
Subject: Python-list Digest, Vol 70, Issue 123
In-Reply-To: <mailman.10425.1247132403.8014.python-list@python.org>
References: <mailman.10425.1247132403.8014.python-list@python.org>
Message-ID: <c140049d0907090331s3e15f277hfc701928ab2419e7@mail.gmail.com>

Hello ,
          When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
problem.

When i==10 you append another empty list to arr, so arr[i] is arr[10].
Index error because there's no arr[10], only arr[0] and arr[1].


Thanks for your prompt reply...

How can i pass this problem


Sincerely
Tanmoy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/e442d413/attachment-0001.html>

From python at mrabarnett.plus.com  Thu Jul  9 06:39:34 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 09 Jul 2009 11:39:34 +0100
Subject: Python-list Digest, Vol 70, Issue 123
In-Reply-To: <c140049d0907090331s3e15f277hfc701928ab2419e7@mail.gmail.com>
References: <mailman.10425.1247132403.8014.python-list@python.org>
	<c140049d0907090331s3e15f277hfc701928ab2419e7@mail.gmail.com>
Message-ID: <4A55C8E6.3040803@mrabarnett.plus.com>

Tanmoy wrote:
> Hello ,
>           When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
> problem.
> 
> When i==10 you append another empty list to arr, so arr[i] is arr[10].
> Index error because there's no arr[10], only arr[0] and arr[1].
>  
> 
> Thanks for your prompt reply...
> 
> How can i pass this problem
> 
You could try appending to arr[-1] instead.

Better still:

     ...
     row = []
     for j in range(0,1001,1):
           row.append(i+j)
     arr.append(row)
     ...


From piet at cs.uu.nl  Thu Jul  9 06:43:43 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 09 Jul 2009 12:43:43 +0200
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
	<cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>
Message-ID: <m2fxd69lwg.fsf@cs.uu.nl>

>>>>> Fred Atkinson <fatkinson at mishmash.com> (FA) wrote:

>FA> On Wed, 08 Jul 2009 12:29:54 +0200, Piet van Oostrum <piet at cs.uu.nl>
>FA> wrote:

>>> Something like:
>>> 
>>> #! /usr/bin/env python
>>> 
>>> import cgi
>>> from os import getenv
>>> 
>>> print "Content-type: text/html"
>>> print
>>> 
>>> ipaddr = (getenv("HTTP_CLIENT_IP") or
>>> getenv("HTTP_X_FORWARDED_FOR") or
>>> getenv("HTTP_X_FORWARDED_FOR") or
>>> getenv("REMOTE_ADDR") or
>>> "UNKNOWN")
>>> 
>>> print ipaddr

>FA> That did it.  

>FA> I wonder why they don't just have a function to return it instead of
>FA> putting you through all of that?  

I see now that I had       getenv("HTTP_X_FORWARDED_FOR") or
duplicated.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From user at example.net  Thu Jul  9 06:49:59 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 12:49:59 +0200
Subject: older pythons
In-Reply-To: <d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
Message-ID: <4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>

Adrian Dziubek wrote:
> The recommended Debian way is update-alternatives. I find it a bit
> unintuitive, so I have to read through the documentation every time I
> use it, but it should be able link a chosen version of python to /usr/
> bin/python. I don't know if it's set up by default, I have only one
> version installed.
> --
> Adrian

what i was asking for is about a way to *INSTALL* and mantain different 
python versions, a task i think is not unusal for developers.

thanks anyway for reply

bye


From reddy.mrp at gmail.com  Thu Jul  9 06:52:44 2009
From: reddy.mrp at gmail.com (m.reddy prasad reddy)
Date: Thu, 9 Jul 2009 16:22:44 +0530
Subject: need to write a assembly progrm
Message-ID: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>

my aim is to run the assembly programs in python.by that we can use that in
the any labs.because we can run the python in the mobiles also.if we write
assembly programs in the mobile ,the mobile act as a tool kit for the
lab.tell me any other solutions for this
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/18f4b7b3/attachment-0001.html>

From rajat.dudeja at gmail.com  Thu Jul  9 06:53:29 2009
From: rajat.dudeja at gmail.com (Rajat)
Date: Thu, 9 Jul 2009 03:53:29 -0700 (PDT)
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com> 
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz> 
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com> 
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
	<mailman.2880.1247134886.8015.python-list@python.org>
Message-ID: <652cca82-44a3-473f-b640-c2336a9cf929@v15g2000prn.googlegroups.com>

On Jul 9, 3:21?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> Rajat wrote:
> > The Notepad process information is fine here. However, with wordpad
> > the results are not much differentiating:
>
> > ---------------------------------------------------------------------------?---
> > wordpad.exe pid: 2832 COMP\rajatd
> > ? ?1C: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?40: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?74: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
> > ? ?F8: Section ? ? ? \BaseNamedObjects
> > \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
> > ? 170: Section ? ? ? \BaseNamedObjects\RotHintTable
> > ? 184: File ?(RW-) ? C:\Documents and Settings\rajatd\My Documents
> > ---------------------------------------------------------------------------?---
> > wordpad.exe pid: 844 COMP\rajatd
> > ? ?1C: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?40: File ?(RW-) ? C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-
> > Controls_6595b64144ccf1df_6.0.2600.5512_x-ww_35d4ce83
> > ? ?74: Section ? ? ? \BaseNamedObjects\ShimSharedMemory
> > ? ?F8: Section ? ? ? \BaseNamedObjects
> > \CiceroSharedMemDefaultS-1-5-21-57989841-1580818891-839522115-1653
> > ? 170: Section ? ? ? \BaseNamedObjects\RotHintTable
> > ? 184: File ?(RW-) ? C:\Documents and Settings\rajatd\My Documents
>
> > Both the wordpad applications opened 2 totally different files kept at
> > different locations on the system.
>
> > So, on the basis of above results one can not say out of these 2
> > wordpad apps which is the right one that could be closed. The only
> > different thing among the two is the PIDs.
>
> Rajat: are you trying to find out which app is holding a file open?
>
> If so -- run handle.exe *for that filename*, as my code does:
>
> handle.exe <filename>
>
> This will only show which apps are holding that file. I suspect
> you're running handle.exe on its own which will show everything
> which is holding handles on anything.
>
> 1) Use wordpad.exe to open c:\temp\blah.txt
>
> 2) Run "handle.exe c:\temp\blah.txt"
>
> 3) Observe (at least on my Win XP Sp3 machine) that *no* process
> has a handle open on c:\temp\blah.txt, including wordpad, which
> presumably opens the file, reads it, and closes it again.
>
> The items you're seeing above are system-level handles which
> wordpad is holding for reasons of its own, but none of them
> is a user filename.
>
> TJG- Hide quoted text -
>
> - Show quoted text -

Thanks Tim for the details. Just further on this, my whole idea is to
close the wordpad / notepad application so that I can delete the file
and the directory where this file resides.

With notepad it is no more a problem. But I'm concerned about the
wordpad now.


From manu3d at gmail.com  Thu Jul  9 06:59:45 2009
From: manu3d at gmail.com (Emanuele D'Arrigo)
Date: Thu, 9 Jul 2009 03:59:45 -0700 (PDT)
Subject: property using a classmethod
Message-ID: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>

Greetings,

today I did something like this:

class MyClass(object):

    @classmethod
    def myClassMethod(self):
         print "ham"

     myProperty = property(myClassMethod, None, None)

As many of you know this doesn't work and returns a TypeError: the
object passed to the property is not a callable function but a
classmethod object, which isn't callable at all. So, how do I do this?
Ultimately all I want is a non-callable class-level attribute
MyClass.myProperty that gives the result of MyClass.myClassMethod().

Can it be done?

Manu


From bearophileHUGS at lycos.com  Thu Jul  9 07:04:10 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 9 Jul 2009 04:04:10 -0700 (PDT)
Subject: count
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com> 
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com> <7xbpnuzw4u.fsf@ruckus.brouhaha.com> 
	<mailman.2865.1247105487.8015.python-list@python.org>
Message-ID: <e4a20167-4c63-4ab3-baf2-be1f41c81fd8@a36g2000yqc.googlegroups.com>

Paul Rubin:
> print x, sum(1 for _ in g)

Don't use that, use my function :-) If g has a __len__ you are wasting
time. And sum(1 ...) is (on my PC) slower.


J. Clifford Dyer:
> if __name__ == '__main__':
> ? ? test_func(summer, 10000000)
> ? ? test_func(tupler, 10000000)
> ? ? test_func(summer, 100000000)
> ? ? test_func(tupler, 100000000)

Have you forgotten my function?

Bye,
bearophile


From larrykavanagh at examiner.ie  Thu Jul  9 07:05:46 2009
From: larrykavanagh at examiner.ie (Larry kavanagh)
Date: Thu, 09 Jul 2009 12:05:46 +0100
Subject: python-ldap
Message-ID: <4A55CF0A.50707@examiner.ie>

Hi,
I need a PYTHON-LDAP package.

I'm trying to install ploneldap and it tells me I need python-ldap 
package first  .. but I can't find one to match my versions.

I'm using plone 3.2.2, Python 2.4.4 and Zope 2.10.7 on a Win32 environment.

Preferable I'd like an EXE as not too familiar with whole plone 
configuration.

The ones I've tried have all told me I need Python 2.4 installed and it 
can't find in the registry. My plone site tells me I'm python 2.4.4 so 
maybe I just need to configure some environment variables or PATHs or 
something prior to running an install ??

Can anyone help me
Thanks
Larry



Please consider the environment before printing this email.

Examiner Publications (Cork) Ltd
Directors:  G. A. Crosbie (Chairman), Thomas J. Murphy (Chief Executive), A.W. Dinan (Secretary), T.P. Crosbie. 
Registered In Dublin, Ireland. Registered number: 73385. Registered Office: City Quarter, Lapps Quay, Cork.





From bearophileHUGS at lycos.com  Thu Jul  9 07:10:53 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 9 Jul 2009 04:10:53 -0700 (PDT)
Subject: Psyco 64 bits
References: <4a55c118$0$48237$14726298@news.sunsite.dk>
Message-ID: <51ae217e-729d-4eac-957e-b01f054e4057@t13g2000yqt.googlegroups.com>

Luis P. Mendes:
> It seems that Psyco cannot be used in such platforms.
> Or is there another version of Psyco for 64 bits platform?
> I googled and arrived to PyPy. ?But I don't know how to use it.

Psyco will be updated, but probably not for 64 bit CPUs. At the moment
PyPy doesn't give you much speed up.
So you can try IronPython, but I don't think it will help. There's
also the Boo language, that's often fast enough.

If your code has few hot spots, then there are many solutions that can
be used. For example Cython, Weave, ShedSkin. Or writing external code
in C/C++/D/Fortran and interfacing with it with a plethora of means,
like ctypes, swig, PIL, Pyd, Boost.Python, Inline, and many other.
Running speed is a big problem in many Python programs, so they have
invented an army of possible solutions.

Bye,
bearophile


From lie.1296 at gmail.com  Thu Jul  9 07:15:45 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 11:15:45 GMT
Subject: older pythons
In-Reply-To: <4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
Message-ID: <Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>

superpollo wrote:
> Adrian Dziubek wrote:
>> The recommended Debian way is update-alternatives. I find it a bit
>> unintuitive, so I have to read through the documentation every time I
>> use it, but it should be able link a chosen version of python to /usr/
>> bin/python. I don't know if it's set up by default, I have only one
>> version installed.
>> -- 
>> Adrian
> 
> what i was asking for is about a way to *INSTALL* and mantain different
> python versions, a task i think is not unusal for developers.
> 
> thanks anyway for reply
> 
> bye

Installing several minor versions (e.g. 2.3, 2.4, 2.5, 3.0) in parallel
has always been supported. Just install them and it should work
"automagically".

However changing the system's default /usr/bin/python is NOT
recommended, especially in linux systems that rely heavily on python for
many of the system tools. If you install from source, you need to check
for some settings to ensure the installer does not install the
/usr/bin/python's symlink. If you install from a package manager, they
usually doesn't change the symlink and you'll need to run a separate
program to change the symlinks (e.g. python-updater in Gentoo, which
will also updates all installed python packages to the appropriate
version. Neat.).

The easiest way to make a specific script use a specific version of
python is by changing its hashbang (#!) line:

instead of:
#!/usr/bin/env python

use
#!/usr/bin/env python2.3

or whatever version it should run on.

AFAIK, no major linux distributions have officially ported to python
3.x. This means switching /usr/bin/python to python3.1 will definitely
break your system. As an alternative, you can always explicitly specify
the version number of python you want to use:

$ python2.5
Python 2.5.4 (r254:67916, Jul  5 2009, 04:12:16)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
$ python2.6
Python 2.6.2 (r262:71600, Jul  5 2009, 04:08:11)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
$ python3.0
Python 3.0.1 (r301:69556, Jul  5 2009, 04:03:20)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
$ python3.0 need3.py
happily running with python 3.0
$ python2 need3.py
SillyError: not running with python 3.0


From piet at cs.uu.nl  Thu Jul  9 07:31:44 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 09 Jul 2009 13:31:44 +0200
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
Message-ID: <m27hyi9jof.fsf@cs.uu.nl>

>>>>> Lacrima <Lacrima.Maxim at gmail.com> (L) wrote:

>L> Thanks for your reply!
>L> My file name is 'trains.py'.
>L> When I do C-h k C-c RET, it shows me help from manual: "C-c RET runs
>L> the command py-execute-import-or-reload
>L>    which is an interactive Lisp function in `python-mode'..." and so
>L> on.

>L> And still when I do C-c RET, I receive "(Shell command succeeded with
>L> no output)"

>L> Any more help would be really appreciated, because I am newbie with
>L> Emacs.

I tested it and I can get this message also. It happens when you have no
Python shell running (*Python* buffer). The python code is then executed
by calling the python shell command and catching the output. This output
is displayed in the *Python Output* buffer. It happens also with C-c C-c
and it will give the same message.

There is a difference, however between C-c C-x and C-c RET: The latter
will import your module, and most modules are written such that
importing them doesn't print anything. If you add something like 
print "test" and the end of file, then "test" will appear in the *Python
Output*  buffer.

If your file has the print "hello world" statement it should display in
the *Python Output* buffer. I checked that.

On the other hand, if you have a python shell running you must make sure
(e.g. with the cd command) that its working directory is the directory
where your python file is located, otherwise the import statement will
not find your file. Unless it is somewhere in the python path. Also the
*Python* buffer will not automatically pop up if it is not visible, in
contrast with the *Python Output* buffer.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From fabiofz at gmail.com  Thu Jul  9 07:35:32 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Thu, 9 Jul 2009 08:35:32 -0300
Subject: Pydev 1.4.7 Released
In-Reply-To: <7blh8oF2367ioU2@mid.individual.net>
References: <mailman.2861.1247094510.8015.python-list@python.org>
	<7blh8oF2367ioU2@mid.individual.net>
Message-ID: <cfb578b20907090435ob708c3ci38ed91e617506d58@mail.gmail.com>

Yes.

On Thu, Jul 9, 2009 at 3:32 AM, Morten Nygaard
Aasnes<morten.aasnes at gmail.com> wrote:
> On 2009-07-08, Fabio Zadrozny <fabiofz at gmail.com> wrote:
>> Hi All,
>>
>> Pydev and Pydev Extensions 1.4.7 have been released
>>
>> Details on Pydev Extensions: http://www.fabioz.com/pydev
>> Details on Pydev: http://pydev.sf.net
>> Details on its development: http://pydev.blogspot.com
>
> Nice! Will this work in Eclipse 3.5 as well?
>
> --
> Morten Nygaard ?snes ? http://twitter.com/mortenaa ? http://identi.ca/mortenaa
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From user at example.net  Thu Jul  9 07:39:37 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 13:39:37 +0200
Subject: older pythons
In-Reply-To: <Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
Message-ID: <4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>

Lie Ryan wrote:

> AFAIK, no major linux distributions have officially ported to python
> 3.x.

http://packages.debian.org/experimental/python3.1

thanks for help


From helvinlui at gmail.com  Thu Jul  9 07:42:37 2009
From: helvinlui at gmail.com (Helvin)
Date: Thu, 9 Jul 2009 04:42:37 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
Message-ID: <7a641820-7e7e-44a8-aae5-9cf9822aab6d@p36g2000prn.googlegroups.com>

On Jul 9, 6:27?pm, Helvin <helvin... at gmail.com> wrote:
> On Jul 9, 11:29?am, Robert Kern <robert.k... at gmail.com> wrote:
>
>
>
>
>
> > On 2009-07-08 18:10, Helvin wrote:
>
> > > Thanks for the fast replies! I will look into how to use VTK now.
> > > Where would I find VTK's explicit support for PyQt?
>
> > Wrapping/Python/vtk/qt4/ in the VTK sources.
>
> > > Because I have installed VTK (using its installer) and pyVTK (using
> > > its setup.py file), but how do I actually use it in my code? According
> > > to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
> > > I have tried 'import vtk', but python can't find the vtk module.
>
> > Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
> > just a library for manipulating VTK files. The VTK Python bindings are part of
> > VTK's distribution itself. Exactly how did you install VTK? Did you compile it
> > yourself?
>
> > --
> > Robert Kern
>
> > "I have come to believe that the whole world is an enigma, a harmless enigma
> > ? that is made terrible by our own mad attempt to interpret it as though it had
> > ? an underlying truth."
> > ? ?-- Umberto Eco
>
> You mean, when I download VTK, the VTK Python bindings come with it?
> I downloaded VTK from:http://vtk.org/files/release/5.4/
>
> I downloaded pyVTK from:http://pypi.python.org/pypi/PyVTK/0.4.67
> And then installed it by the command 'python setup.py install'
> according to:http://cens.ioc.ee/projects/pyvtk/
> I understand that this command runs the file called 'setup.py' that
> came with the pyVTK download.
>
> Thanks so much for your help! I am very desperate now...
>
> Helvin

I googled: vtk for beginners python.
>From there, I found this: http://www.nabble.com/pls-help-how-to-install-VTK-and-run-td14977428.html
And from there, this: http://www-viz.tamu.edu/courses/viza658/08spring/tutorials/WinVTKInstall.html

This last one has very detailed info about how to get started with
VTK. I am now redoing the installing VTK thing. Hope it will work.

Helvin


From mondi at cs.unibo.it  Thu Jul  9 07:50:20 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Thu, 09 Jul 2009 11:50:20 +0000
Subject: hoe to build a patched socketmodule.c
Message-ID: <h34dsu$a4j$1@lec.cs.unibo.it>

Hi all, I need to patch socketmodule.c (the _socket module) in order to
add support to an experimental socket family.

I'm guessing about the patched module build process: does a stand alone
build script using distutils makes sense, or have I to patch
sockmodule.c, eventualy rename it, modify setup.py inside python sources
to let it know about the new module, and then rebuild whole python?
I think the latter makes more sense, because I suppose socketmodule
could not be build stand alone, but need the whole python build system,
in order to have right definition specified by a Makefile generated by
autotools from inside python sources.
Or maybe distutils is able to retreive the whole build system? I don't
think so, because there are no requirement about having python source
tree installed.

If I have to go for the second way, then how could I distribuite the
patched _socket module? I could not use distutils, have I to distribuite
 the already built .so with only a script to install it, and the source
code in another directory?

Thanks a lot
	jacopo

PS correct my english please, is the only way I have to improve it!


From rashidsdpk at gmail.com  Thu Jul  9 07:59:28 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Thu, 9 Jul 2009 04:59:28 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <fc38a885-cf1a-4418-a82f-83f8d7c3c61e@37g2000yqp.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.
for more details on http://0nanotechnology0.blogspot.com


From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul  9 07:59:44 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 09 Jul 2009 13:59:44 +0200
Subject: property using a classmethod
In-Reply-To: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
Message-ID: <4a55db9e$0$10243$426a74cc@news.free.fr>

Emanuele D'Arrigo a ?crit :
> Greetings,
> 
> today I did something like this:
> 
> class MyClass(object):
> 
>     @classmethod
>     def myClassMethod(self):

<ot> Usually, the first argument of classmethods is named 'cls' </ot>

>          print "ham"
> 
>      myProperty = property(myClassMethod, None, None)
> 
> As many of you know this doesn't work and returns a TypeError: the
> object passed to the property is not a callable function but a
> classmethod object, which isn't callable at all.  So, how do I do this?
> Ultimately all I want is a non-callable class-level attribute
> MyClass.myProperty

properties *are* class attributes.

> that gives the result of MyClass.myClassMethod().
> 
> Can it be done?

You could write your own custom descriptor. Or just use an additional 
level of indirection, ie:

    myProperty = property(lambda self: self.myClassMethod())


but since you already have myClassMethod available, I don't see the 
point. What problem are you trying to solve exactly ?



From lie.1296 at gmail.com  Thu Jul  9 08:10:33 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 12:10:33 GMT
Subject: older pythons
In-Reply-To: <4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
Message-ID: <Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>

superpollo wrote:
> Lie Ryan wrote:
> 
>> AFAIK, no major linux distributions have officially ported to python
>> 3.x.
> 
> http://packages.debian.org/experimental/python3.1
> 
> thanks for help

Note the word "experimental"


From michael at stroeder.com  Thu Jul  9 08:17:49 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Thu, 09 Jul 2009 14:17:49 +0200
Subject: python-ldap
In-Reply-To: <mailman.2883.1247138347.8015.python-list@python.org>
References: <mailman.2883.1247138347.8015.python-list@python.org>
Message-ID: <eo3hi6-oa4.ln1@nb2.stroeder.com>

Larry kavanagh wrote:
> I need a PYTHON-LDAP package.
> 
> I'm trying to install ploneldap and it tells me I need python-ldap
> package first  .. but I can't find one to match my versions.
> 
> I'm using plone 3.2.2, Python 2.4.4 and Zope 2.10.7 on a Win32 environment.

Did you check all the links on this page?

  http://www.python-ldap.org/download.shtml

There's a MSI installer for Python 2.4 on Win32:

http://pypi.python.org/packages/2.4/p/python-ldap/python-ldap-2.3.8.win32-py2.4.exe#md5=35da547711280c18bd4ccd6e637cdf9b

There has been an update of the .egg files recently (also link on the
download page above).

Ciao, Michael.

-- 
Michael Str?der
E-Mail: michael at stroeder.com
http://www.stroeder.com


From xahlee at gmail.com  Thu Jul  9 08:19:29 2009
From: xahlee at gmail.com (Xah Lee)
Date: Thu, 9 Jul 2009 05:19:29 -0700 (PDT)
Subject: OT: unix to Windows technology
References: <db87562d-2c55-4f2f-8df0-5b3631235b93@i18g2000pro.googlegroups.com>
	<4a54ceb0$0$5898$607ed4bc@cv.net>
	<16430ee7-888e-42ef-9c84-14df4b78ee04@p36g2000prn.googlegroups.com>
Message-ID: <0de99585-6a35-498d-b5d1-6eb8724c41b3@m3g2000pri.googlegroups.com>

a fried showed me this today:

http://xahlee.org/funny/Microsoft_eula.html

not sure which site originally reported it.

  Xah
? http://xahlee.org/

?


From user at example.net  Thu Jul  9 08:26:37 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 14:26:37 +0200
Subject: older pythons
In-Reply-To: <Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
	<Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
Message-ID: <4a55e1fb$0$1116$4fafbaef@reader3.news.tin.it>

Lie Ryan wrote:
> superpollo wrote:
> 
>>Lie Ryan wrote:
>>
>>
>>>AFAIK, no major linux distributions have officially ported to python
>>>3.x.
>>
>>http://packages.debian.org/experimental/python3.1
>>
>>thanks for help
> 
> 
> Note the word "experimental"

i noticed. isn't experimental official? i thought it was...

thanks for your reply

bye and god bless you


From marco at sferacarta.com  Thu Jul  9 08:37:11 2009
From: marco at sferacarta.com (Marco Mariani)
Date: Thu, 09 Jul 2009 14:37:11 +0200
Subject: older pythons
In-Reply-To: <4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
Message-ID: <Xvl5m.4792$vG4.2383@tornado.fastwebnet.it>

superpollo wrote:

> what i was asking for is about a way to *INSTALL* and mantain different 
> python versions, a task i think is not unusal for developers.

Check out virtualenv, I ask myself how I could work without it.

http://pypi.python.org/pypi/virtualenv



From lie.1296 at gmail.com  Thu Jul  9 08:37:30 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 12:37:30 GMT
Subject: property using a classmethod
In-Reply-To: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
Message-ID: <ewl5m.3746$ze1.3371@news-server.bigpond.net.au>

Emanuele D'Arrigo wrote:
> Greetings,
> 
> today I did something like this:
> 
> class MyClass(object):
> 
>     @classmethod
>     def myClassMethod(self):
>          print "ham"
> 
>      myProperty = property(myClassMethod, None, None)
> 
> As many of you know this doesn't work and returns a TypeError: the
> object passed to the property is not a callable function but a
> classmethod object, which isn't callable at all.

That code runs fine for me. Although I doubt the behavior is what you
wanted to do.

> So, how do I do this?
> Ultimately all I want is a non-callable class-level attribute
> MyClass.myProperty that gives the result of MyClass.myClassMethod().

This works like what you seem to want (it's ugly):

class MyClass(object):
    class _MyClass(object):
        @classmethod
        def myClassMethod(cls):
            return 'ham'
        @property
        def myProperty(self):
            return MyClass._MyClass.myClassMethod()
    @classmethod
    def myClassMethod(cls):
        return MyClass._MyClass.myClassMethod()
    @property
    def myProperty(self):
        return MyClass._MyClass.myClassMethod()

    def __call__(self, *args, **kargs):
        # this is __init__
        return MyClass._MyClass(*args, **kargs)
# note this is NOT a real MyClass instantiation
MyClass = MyClass()

$ python -i ./strangeclass.py
>>> MyClass.myClassMethod()
'ham'
>>> MyClass.myProperty
'ham'
>>> mc = MyClass()
>>> mc.myProperty
'ham'
>>> mc.myClassMethod()
'ham'


From mukherjee.tanmoy at gmail.com  Thu Jul  9 08:43:57 2009
From: mukherjee.tanmoy at gmail.com (Tanmoy)
Date: Thu, 9 Jul 2009 18:13:57 +0530
Subject: Hello
Message-ID: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>

>
> Hello ,
>          When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
> problem.
>
> When i==10 you append another empty list to arr, so arr[i] is arr[10].
> Index error because there's no arr[10], only arr[0] and arr[1].
>
> Thanks for your prompt reply...
>
> How can i pass this problem
>
>  You could try appending to arr[-1] instead.

Better still:

   ...
   row = []
   for j in range(0,1001,1):
         row.append(i+j)
   arr.append(row)
   ...
I tried both the ways... the only thing is its not coming like 0 10
20.......1000 . Its coming like 0,1,2,........1000.....Any answer to the
problem.
Thanks
Tanmoy Mukherjee
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/b9ae7baf/attachment-0001.html>

From davea at ieee.org  Thu Jul  9 08:44:18 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 08:44:18 -0400
Subject: function local namespace question
In-Reply-To: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
References: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
Message-ID: <4A55E622.3050906@ieee.org>

Paul LaFollette wrote:
> Kind people,
>
> Using Python 3.1 under FreeBSD and WinXP.
>
> I've been tearing my hair out trying to solve this myself, but I need
> to ask for help.   I want (for obscure reasons) to be able to log
> transactions in the namespace(s) of a script.  Specifically I would
> like to log creation of identifiers, changes in the binding of
> identifiers ("assignment") and lookups.  This turns out to be pretty
> easy in the global and local namespaces... I simply subclass dict,
> override the appropriate operations to include the logging operations
> I want, and then exec the code using my dictionaries as the global and
> local namespaces.  All  of this  works just dandy until I try to
> extend it to functions.
>
> I cannot figure out any way to get a hook into the local namespace of
> a user defined function.  I have tried making a wrapper class that
> grabs the function call and then uses exec to invoke
> myfunction.__code__ with my own dictionaries.  This runs the (no
> argument) function properly (losing the return value, but I can deal
> with that) but never accesses the local logging dictionary that I
> specify in the exec() call. Perhaps the local namespace of a function
> is not a dict at all?
>
> Anyway, is there any way (however clumsy) to do what I want to do?
> Thank you for your help.
> Paul
>
> ---------------------------
> Paul LaFollette
> CIS Department
> Temple University
> paul.lafollette(at)temple.edu
> www.cis.temple.edu/~lafollet
>
>   
Is there a way?  Undoubtedly.

The simplest way that occurs to me is to have a pre-pass that rewrites 
the .pyc files, adding instrumentation to the byte-code.  You could also 
recompile the Python interpreter, with some extra hooks in it.  That 
could get tricky, as you don't want to instrument the code that's doing 
the tracking.  Fnally, you could hook into the byte-code loader, doing 
the changes at that time.

As always, if the code is for commercial use, beware of infringing on 
patents.  I have a few in the 3rd area (though the ownership is with 
other companies;  I was just the inventor.)

DaveA



From deets at nospam.web.de  Thu Jul  9 08:54:25 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 09 Jul 2009 14:54:25 +0200
Subject: function local namespace question
References: <65d199b50907081035l65ef8f2bn5a049aa3c1bd9b93@mail.gmail.com>
	<mailman.2887.1247143473.8015.python-list@python.org>
Message-ID: <7bm7bsF22aoa9U1@mid.uni-berlin.de>

Dave Angel wrote:

> Paul LaFollette wrote:
>> Kind people,
>>
>> Using Python 3.1 under FreeBSD and WinXP.
>>
>> I've been tearing my hair out trying to solve this myself, but I need
>> to ask for help.   I want (for obscure reasons) to be able to log
>> transactions in the namespace(s) of a script.  Specifically I would
>> like to log creation of identifiers, changes in the binding of
>> identifiers ("assignment") and lookups.  This turns out to be pretty
>> easy in the global and local namespaces... I simply subclass dict,
>> override the appropriate operations to include the logging operations
>> I want, and then exec the code using my dictionaries as the global and
>> local namespaces.  All  of this  works just dandy until I try to
>> extend it to functions.
>>
>> I cannot figure out any way to get a hook into the local namespace of
>> a user defined function.  I have tried making a wrapper class that
>> grabs the function call and then uses exec to invoke
>> myfunction.__code__ with my own dictionaries.  This runs the (no
>> argument) function properly (losing the return value, but I can deal
>> with that) but never accesses the local logging dictionary that I
>> specify in the exec() call. Perhaps the local namespace of a function
>> is not a dict at all?
>>
>> Anyway, is there any way (however clumsy) to do what I want to do?

You might consider using the trace-functionality of python, exposed throug

 sys.settrace

It's very expensive of course to do that.

Diez


From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul  9 08:56:18 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 09 Jul 2009 14:56:18 +0200
Subject: property using a classmethod
In-Reply-To: <ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
Message-ID: <4a55e8e0$0$8041$426a34cc@news.free.fr>

Lie Ryan a ?crit :
> Emanuele D'Arrigo wrote:
(snip)
>> Ultimately all I want is a non-callable class-level attribute
>> MyClass.myProperty that gives the result of MyClass.myClassMethod().
> 
> This works like what you seem to want (it's ugly):

Ugly, indeed. And an extreme case of arbitrary overcomplexification too :-/

(snip rube goldberg code)



From user at example.net  Thu Jul  9 09:04:30 2009
From: user at example.net (superpollo)
Date: Thu, 09 Jul 2009 15:04:30 +0200
Subject: older pythons
In-Reply-To: <Xvl5m.4792$vG4.2383@tornado.fastwebnet.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Xvl5m.4792$vG4.2383@tornado.fastwebnet.it>
Message-ID: <4a55eadd$0$1108$4fafbaef@reader3.news.tin.it>

Marco Mariani wrote:
> superpollo wrote:
> 
>> what i was asking for is about a way to *INSTALL* and mantain 
>> different python versions, a task i think is not unusal for developers.
> 
> 
> Check out virtualenv, I ask myself how I could work without it.
> 
> http://pypi.python.org/pypi/virtualenv
> 

much obliged!


From lie.1296 at gmail.com  Thu Jul  9 09:20:19 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 13:20:19 GMT
Subject: Catching control-C
In-Reply-To: <c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
Message-ID: <n8m5m.3759$ze1.2493@news-server.bigpond.net.au>

Michael Mossey wrote:
> On Jul 6, 2:47 pm, Philip Semanchuk <phi... at semanchuk.com> wrote:
>> On Jul 6, 2009, at 5:37 PM, Michael Mossey wrote:
>>
>>> What is required in a python program to make sure it catches a  
>>> control-
>>> c on the command-line? Do some i/o? The OS here is Linux.
>> You can use a try/except to catch a KeyboardInterrupt exception, or  
>> you can trap it using the signal module:http://docs.python.org/library/signal.html
>>
>> You want to trap SIGINT.
>>
>> HTH
>> Philip
> 
> Thanks to both of you. However, my question is also about whether I
> need to be doing i/o or some similar operation for my program to
> notice in any shape or form that Control-C has been pressed. In the
> past, I've written Python programs that go about their business
> ignoring Ctrl-C. Other programs respond to it immediately by exiting.
> I think the difference is that the latter programs are doing i/o. But
> I want to understand better what the "secret" is to responding to a
> ctrl-C in any shape or form.
> 
> For example, does trapping SIGINT always work, regardless of what my
> process is doing?
> 
> Thanks,
> Mike

Are you asking: "when would the python interpreter process
KeyboardInterrupt?"

In a multi threaded python program (where KeyboardInterrupt doesn't
always work), only the main thread can process KeyboardInterrupt; thus
the main thread must regain control before the interrupt is raised.
Normally, python will context switch (i.e. thread switch) every 100
interpreter "ticks", but when the interpreter received a SIGINT, the
interpreter will try to context switch as fast as it can (every tick) to
allow the main thread to regain control. So the answer is in
multithreaded python program: "when the main thread regains control"

In single threaded python program, the currently running thread is
always the main thread (which can handle KeyboardInterrupt). I believe
SIGINT is checked at every ticks. But SIGINT cannot interrupt atomic
operations (i.e. it cannot interrupt long operations that takes a single
tick).

An example, where python have difficulties processing KeyboardInterrupt:
>>> print 'foo'*10000000
...foofoofoo...
because printing a string is an atomic operation

I believe a tick in python is equivalent to a single bytecode, but
please correct me if I'm wrong.


From python at mrabarnett.plus.com  Thu Jul  9 09:25:36 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 09 Jul 2009 14:25:36 +0100
Subject: Hello
In-Reply-To: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
References: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
Message-ID: <4A55EFD0.7080408@mrabarnett.plus.com>

Tanmoy wrote:
>     Hello ,
>              When i==0 you append an empty list to arr, so arr[i] is
>     arr[0]. No
>     problem.
> 
>     When i==10 you append another empty list to arr, so arr[i] is arr[10].
>     Index error because there's no arr[10], only arr[0] and arr[1].
>      
>     Thanks for your prompt reply...
> 
>     How can i pass this problem
> 
> You could try appending to arr[-1] instead.
> 
> Better still:
> 
>    ...
>    row = []
>    for j in range(0,1001,1):
>          row.append(i+j)
>    arr.append(row)
>    ...
> I tried both the ways... the only thing is its not coming like 0 10 
> 20.......1000 . Its coming like 0,1,2,........1000.....Any answer to the 
> problem.
> 
Each row should be 1 more than the previous row and each column should
be 10 more than the previous column. Just swap your ranges.


From Lacrima.Maxim at gmail.com  Thu Jul  9 09:28:07 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Thu, 9 Jul 2009 06:28:07 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
	<m27hyi9jof.fsf@cs.uu.nl>
Message-ID: <cafc471d-e1c3-4024-8090-898408415d8f@t13g2000yqt.googlegroups.com>

On Jul 9, 2:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Lacrima <Lacrima.Ma... at gmail.com> (L) wrote:
> >L> Thanks for your reply!
> >L> My file name is 'trains.py'.
> >L> When I do C-h k C-c RET, it shows me help from manual: "C-c RET runs
> >L> the command py-execute-import-or-reload
> >L> ? ?which is an interactive Lisp function in `python-mode'..." and so
> >L> on.
> >L> And still when I do C-c RET, I receive "(Shell command succeeded with
> >L> no output)"
> >L> Any more help would be really appreciated, because I am newbie with
> >L> Emacs.
>
> I tested it and I can get this message also. It happens when you have no
> Python shell running (*Python* buffer). The python code is then executed
> by calling the python shell command and catching the output. This output
> is displayed in the *Python Output* buffer. It happens also with C-c C-c
> and it will give the same message.
>
> There is a difference, however between C-c C-x and C-c RET: The latter
> will import your module, and most modules are written such that
> importing them doesn't print anything. If you add something like
> print "test" and the end of file, then "test" will appear in the *Python
> Output* ?buffer.
>
> If your file has the print "hello world" statement it should display in
> the *Python Output* buffer. I checked that.
>
> On the other hand, if you have a python shell running you must make sure
> (e.g. with the cd command) that its working directory is the directory
> where your python file is located, otherwise the import statement will
> not find your file. Unless it is somewhere in the python path. Also the
> *Python* buffer will not automatically pop up if it is not visible, in
> contrast with the *Python Output* buffer.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

Thank you for really useful and detailed explanation. Now I can test
my code using Emacs.
But I think it works for me in a little bit different way.
My file contains only the print 'hello world'.
If I have no python shell running, then:
a) C-c RET opens *Python Output* buffer without any output and with
'Shell command succeeded with no output' message at the bottom
b) C-c C-c opens *Python Output* with appropriate 'hello world'
message.

Then I run python shell with C-c ! command. And:
a) C-c RET opens *Python* buffer and prints 'hello world' in the
python shell
b) C-c C-c gives the same result.

With regards, Max


From davea at ieee.org  Thu Jul  9 09:28:29 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 09:28:29 -0400
Subject: tough-to-explain Python
In-Reply-To: <7blh0eF23r79rU1@mid.individual.net>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2847.1247068773.8015.python-list@python.org>
	<7blh0eF23r79rU1@mid.individual.net>
Message-ID: <4A55F07D.7040400@ieee.org>

greg wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
>> By the time I graduated, I had five six-level languages
>                                       ^^^
>
> Are they languages that you have to edit using vi? :-)
>
Back then I didn't need glasses.  That was of course intended to be  
"six high-level languages"




From shinejose22 at gmail.com  Thu Jul  9 09:40:18 2009
From: shinejose22 at gmail.com (Shine Jose)
Date: Thu, 9 Jul 2009 08:40:18 -0500
Subject: Problem with two instances of PySerial
Message-ID: <a27b2f730907090640od5e09c1g17caf0cdc5b04894@mail.gmail.com>

Hello friends,I am developing an application to read data from serial port
and display it on the screen using GUI developed in pyQT. For this I have
instantiated the GUI as well as pySerial objects in the main thread. I have
provided a button 'Read' which when clicked by the user reads from the
serial port using read() method of pySerial. However, for debugging purposes
I also want to poll the serial port continuously for arrival of data and
display on screen. I achieve this by creating a separate worker thread to
poll the serial port for arrival of data and then updating the required
widget in main thread of program. For polling the serial port, I create a
separate instance of pySerial object. However, I am unable to read any data
in the worker thread. Can the reason for this be 2 instances of pySerial
objects being connected to serial port. The reason I had this doubt was
because Serial.Connect() in the worker thread did not throw any exception &
isOpen() method returns true.
I request you to help me in figuring out the problem.

-- 
Regards,
Shine Jose
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/fd28dc16/attachment-0001.html>

From davea at ieee.org  Thu Jul  9 09:41:38 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 09:41:38 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <4A55F392.3080404@ieee.org>

m.reddy prasad reddy wrote:
> can any one tell me how to write assembly language programs in python...if
> no is there any other way to write the programs in python
>
> Reddi prasad reddy
> ph.no:09958083797
>
>   
Assembly language is a different programming language than Python.  You 
can use both in the same process, much in the same way you can use C or 
C++ with Python.  In fact, some of the system DLL's are written (partly) 
in assembler, though mostly in C or C++.

You'll need to tell us what your real goal is.  Are you a python 
programmer trying to optimize some loop?  Are you taking a course in 
assembler, and hope that somehow Python will help?  Do you have Python 
installed on your system?  What system is it?

As far as I know, Python has no "inline assembler" mode, as C does.   So 
anything written in assembler would be in a separate DLL, not mixed in 
your .py files.  It's not hard to mix assembly files with C or C++ files 
(or Pascal, or dozens of other compiled languages), and link them into a 
single DLL.  But Python's access to that DLL will be done through a 
module like ctypes, or SWIG.


DaveA


From nleioatt at gmail.com  Thu Jul  9 09:42:06 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 9 Jul 2009 06:42:06 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
Message-ID: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>

I've seen a lot of posts on this problem, but none seems to help.
Here is the code:
/code

file = open(prefix1)
text = file.readlines()
len = len(text)
fields = text[1].split()
num_rows = int(fields[1])
num_cols = int(fields[2])

U1_matrix = []

print fields
print repr(fields)
print len(fields)

for line in text[2: num_rows+2]:
    fields = line.split()
#    print "fields", fields, line
    for i in range(len(fields)):
        fields[i] = float(fields[i])
    U1_matrix.append(fields)

/*code

prefix is a space/line delimited ascii file that represents a 2D
matrix.  i'm trying to read in 2 matrices from different files, strip
away the header stuff and then take the dot product of the 2
matrices.  any help is much appreciated.

thanks,
nick


From gabriel.rossetti at arimaz.com  Thu Jul  9 09:43:01 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Thu, 09 Jul 2009 15:43:01 +0200
Subject: Blocking XMPP API?
Message-ID: <4A55F3E5.8040800@arimaz.com>

Hello everyone,

I am looking for blocking XMPP API. I'm wanting to make a webservice 
that uses XMPP, but all the XMPP libs I find are non-blocking (i.e. w/ 
callbacks). I'd like to be able to do something like :

cl = Client("test at domain.com/res01", "password",)
msg = "<m....."
result = cl.send(msg)
print "I got '%s'" % str(result)

any ideas? Using Java I have Smack which can either get msgs sync or 
async, but I found nothing that can do this in Python.

Thanks,
Gabriel

-- 
Arimaz SA
Ing?nieur en Informatique
Av. du 24 Janvier 11
Ateliers de la Ville de Renens, Atelier 5
1020 Renens, Switzerland
www.arimaz.com
www.mydeskfriend.com
Mob: +41-(0)79-539-0069
Tel: +41-(0)21-566-7343



From benjamin.kaplan at case.edu  Thu Jul  9 09:47:53 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Thu, 9 Jul 2009 09:47:53 -0400
Subject: tough-to-explain Python
In-Reply-To: <b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
Message-ID: <ec96e1390907090647n572055dbq306b2cd48f78645d@mail.gmail.com>

On Thu, Jul 9, 2009 at 1:05 AM, Simon Forman<sajmikins at gmail.com> wrote:
> Everyone gets so caught up in programming via languages that
> you get, well, people trying to teach "Computer Programming" as if it
> were only necessary to grok a language, rather than grokking /symbol
> manipulation/ itself.
>
>

+1 QOTW.

I'm a CS major and this is exactly what I see happening in the intro
to CS courses. In class, the "Intro to Programming" students are
showed how to write Java code. Then they try their homework and are
completely lost because they were never taught how to think like a
programmer so they don't understand how to approach the question.


From lutz.horn at fastmail.fm  Thu Jul  9 09:50:02 2009
From: lutz.horn at fastmail.fm (Lutz Horn)
Date: Thu, 09 Jul 2009 15:50:02 +0200
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <4A55F58A.9060003@fastmail.fm>

Hi,

Nick schrieb:
> I've seen a lot of posts on this problem, but none seems to help.

Could you please post a sample input file and the exact error message?

Thanks
Lutz
-- 
Strike Out ? http://www.fourmilab.ch/documents/strikeout


From benjamin.kaplan at case.edu  Thu Jul  9 09:51:49 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Thu, 9 Jul 2009 09:51:49 -0400
Subject: older pythons
In-Reply-To: <Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
	<Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
Message-ID: <ec96e1390907090651y30184f42jb32fa76c99255849@mail.gmail.com>

On Thu, Jul 9, 2009 at 8:10 AM, Lie Ryan<lie.1296 at gmail.com> wrote:
> superpollo wrote:
>> Lie Ryan wrote:
>>
>>> AFAIK, no major linux distributions have officially ported to python
>>> 3.x.
>>
>> http://packages.debian.org/experimental/python3.1
>>
>> thanks for help
>
> Note the word "experimental"

Assuming that Debian does the same thing as Ubuntu (which is highly
likely), Python3.1 won't install itself as the default. Too many
system features depend on Python 2.x.
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From fridrik at pyth.net  Thu Jul  9 09:53:29 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 13:53:29 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <3A693537-927D-44B1-840A-D97FACFB6809@pyth.net>

Look at:

   len = len(text)

You're overriding `len` (a built-in method), with an integer  
(`len(text)`).  You then call:

   for i in range(len(fields)):

But `len` is no longer a callable, but merely an integer.

Regards,
Fri?rik M?r

P.S. While this is a fairly obvious problem it's usually a good idea  
to post working code and a traceback when requesting help.

From gagsl-py2 at yahoo.com.ar  Thu Jul  9 09:53:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 09 Jul 2009 10:53:42 -0300
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
	<mailman.2880.1247134886.8015.python-list@python.org>
	<652cca82-44a3-473f-b640-c2336a9cf929@v15g2000prn.googlegroups.com>
Message-ID: <op.uwszjsc2x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 09 Jul 2009 07:53:29 -0300, Rajat <rajat.dudeja at gmail.com>  
escribi?:

> Thanks Tim for the details. Just further on this, my whole idea is to
> close the wordpad / notepad application so that I can delete the file
> and the directory where this file resides.
>
> With notepad it is no more a problem. But I'm concerned about the
> wordpad now.

I don't see Wordpad keeping the file open either.
If you can't remove the file, use "handle.exe filename.txt" to discover  
which process is holding it open, as Tim already explained.

-- 
Gabriel Genellina



From R.Brodie at rl.ac.uk  Thu Jul  9 10:02:27 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Thu, 9 Jul 2009 15:02:27 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <h34t9k$kp8$1@south.jnrs.ja.net>


"Nick" <nleioatt at gmail.com> wrote in message 
news:e54c4461-c0b7-42fb-8542-cefd7bf5f89f at h18g2000yqj.googlegroups.com...

> file = open(prefix1)
> text = file.readlines()
> len = len(text)

You have redefined two built-in functions "file" and "len" in the first three lines.
This is usually considered poor practice. Stick to meaningless variable names,
it's safer (only joking).

TypeError: 'int' object is not callable". This means that something you thought
was a function is in fact an integer. It's helpful to post/look at the line number of
the error; "how is this line failing", is much easier to answer than
"how is my program failing".

print len(fields)

Here len is an integer, because you redefined it in line 3. I'm guessing this is the
problem. 




From davea at ieee.org  Thu Jul  9 10:04:23 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 10:04:23 -0400
Subject: Hello
In-Reply-To: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
References: <c140049d0907090543y5fda3309u1f0353bcaba6c0e7@mail.gmail.com>
Message-ID: <4A55F8E7.6090304@ieee.org>

You could pick a much better title.  And apparently you started a new 
thread with this one.  When responding to an existing message, you ought 
to reply-all to the existing message, rather than starting a new thread.

Tanmoy wrote:
>> Hello ,
>>          When i==0 you append an empty list to arr, so arr[i] is arr[0]. No
>> problem.
>>
>> When i==10 you append another empty list to arr, so arr[i] is arr[10].
>> Index error because there's no arr[10], only arr[0] and arr[1].
>>
>> Thanks for your prompt reply...
>>
>> How can i pass this problem
>>
>>  You could try appending to arr[-1] instead.
>>     
>
> Better still:
>
>    ...
>    row = []
>    for j in range(0,1001,1):
>          row.append(i+j)
>    arr.append(row)
>    ...
> I tried both the ways... the only thing is its not coming like 0 10
> 20.......1000 . Its coming like 0,1,2,........1000.....Any answer to the
> problem.
> Thanks
> Tanmoy Mukherjee
>
>   
If you want the row to count by 10's you have to build it that way.  You 
have the arguments to the ranges backwards.  Try:


arr=[]
for i in range(1001):
   row = []
   for j in range(0,1010,10):
         row.append(i+j)
   arr.append(row)

Coincidentally, once you reverse them, the original problem would go 
away.  But this is better anyway, as it makes it clear what's 
happening.  You are building 1001 rows, each containing non-contiguous 
numbers.

DaveA



From timmyt at smarttypes.org  Thu Jul  9 10:07:52 2009
From: timmyt at smarttypes.org (timmyt)
Date: Thu, 9 Jul 2009 07:07:52 -0700 (PDT)
Subject: a little wsgi framework
References: <baf31c46-62be-44ba-9ba9-698a2a292fe3@t21g2000yqi.googlegroups.com>
	<4a53132c$0$10839$426a34cc@news.free.fr>
Message-ID: <103cb80e-5a5a-4c41-ae7c-c0ae122cfebf@b25g2000prb.googlegroups.com>

On Jul 7, 5:19?am, Bruno Desthuilliers <bruno.
42.desthuilli... at websiteburo.invalid> wrote:
> timmyt a ?crit :
>
> > i'm interested in getting opinions on a smallwsgiframework i
> > assembled from webob, sqlalchemy, genshi, and various code fragments i
> > found on the inter-tubes
>
> > here is the interesting glue - any comments / suggestions would be
> > much appreciated
>
> <meta>
> Well... My first comment would be about the usefulness of yet another
> Python web framework, but let's not worry about this...
> </meta>
>
> > ------------------
> > thewsgiapp
> > ------------------
> > def application(environ, start_response):
> > ? ? path = environ.get('PATH_INFO', '').lstrip('/')
>
> > ? ? for regex, callback in urls:
> > ? ? ? ? match = re.search(regex, path)
>
> I don't know where these "urls" come from. But anyway : if they live in
> some sort of long-running process, you may want to precompile them.
>
> > ? ? ? ? if match:
> > ? ? ? ? ? ? environ['myapp.url_args'] = match.groups()
> > ? ? ? ? ? ? request = webob.Request(environ)
>
> > ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? return callback(request, start_response)
> > ? ? ? ? ? ? except Exception, ex:
>
> How are redirect etc handled ?
>
> > ? ? ? ? ? ? ? ? start_response('500 Internal Server Error', [('Content-
> > Type', 'text/plain')])
> > ? ? ? ? ? ? ? ? return [traceback.format_exc()]
>
> A configuration option controlling the display of the traceback would be
> fine - I surely don't want the traceback being displayed to anyone when
> ? the app goes into production.
>
> Also, logging the error and traceback might be useful.
>
> > ? ? start_response('404 Not Found', [('Content-Type', 'text/plain')])
> > ? ? return ["Couldn't find the URL specified."]
>
> And in both cases, having the ability to use "custom" 500 and 404 pages
> might be nice too.
>
>
>
> > ----------------------------------
> > the controller decorator
> > ----------------------------------
> > def web_decorator(filename, method='html'):
>
> > ? ? def decorator(target):
>
> May I suggest some renaming here ?
>
> filename => path (or 'template_path' ?)
> method ? => content_type
> target ? => controller or function or callback or....
>
> > ? ? ? ? def wrapper(request, start_response):
>
> > ? ? ? ? ? ? #genshi TemplateLoader
> > ? ? ? ? ? ? template = loader.load(filename)
>
> > ? ? ? ? ? ? global config
>
> Probably not thread-safe....
>
> > ? ? ? ? ? ? try:
> > ? ? ? ? ? ? ? ? return_dict = target(request, start_response)
> > ? ? ? ? ? ? ? ? return_string = template.generate(**return_dict).render
> > (method)
>
> Renaming again:
> return_dict => context
> return_string => data or text or ???
>
> > ? ? ? ? ? ? ? ? config['database.Session'].commit()
> > ? ? ? ? ? ? except:
> > ? ? ? ? ? ? ? ? config['database.Session'].rollback()
> > ? ? ? ? ? ? ? ? raise
> > ? ? ? ? ? ? finally:
> > ? ? ? ? ? ? ? ? config['database.Session'].remove()
>
> This doesn't leave much control on transactions... Sometimes you want to
> handle it manually one way or another.
>
> > ? ? ? ? ? ? #TODO: alter 'Content-Type' per method being passed
> > ? ? ? ? ? ? start_response('200 OK', [('Content-Type', 'text/html')])
> > ? ? ? ? ? ? return [return_string]
>
> Ok, so here again, I don't understand how redirects can work. Also, if
> you do use start_response here, I don't get why you still pass it to the
> callback function.
>
> > ? ? ? ? return wrapper
>
> > ? ? return decorator
>
> slightly OT, but preserving infos on the decorated function might help
> too (introspection, debugging etc).
>
> My 2 cents...

thank you gentlemen

i'm now looking for Redirect exceptions as well, and returning the
appropriate response code (stole this idea from turbogears)

i like doing the response codes and exceptions myself which is why i'm
not using the webob response - i think it's more explicit and
straightforward

the conditional display of errors goes without say - that will be
trivial to add

the 'global config' line was an error - config is a module level
variable set before the application definition

i assume as long as i don't write to the config variable within the
application it is thread-safe - is that correct

the underlying assumption is the wsgi application setup does not have
to be thread safe - this is only run once per process








From nleioatt at gmail.com  Thu Jul  9 10:08:05 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 9 Jul 2009 07:08:05 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
Message-ID: <75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>

On Jul 9, 10:02 am, "Richard Brodie" <R.Bro... at rl.ac.uk> wrote:
> "Nick" <nleio... at gmail.com> wrote in message
>
> news:e54c4461-c0b7-42fb-8542-cefd7bf5f89f at h18g2000yqj.googlegroups.com...
>
> > file = open(prefix1)
> > text = file.readlines()
> > len = len(text)
>
> You have redefined two built-in functions "file" and "len" in the first three lines.
> This is usually considered poor practice. Stick to meaningless variable names,
> it's safer (only joking).
>
> TypeError: 'int' object is not callable". This means that something you thought
> was a function is in fact an integer. It's helpful to post/look at the line number of
> the error; "how is this line failing", is much easier to answer than
> "how is my program failing".
>
> print len(fields)
>
> Here len is an integer, because you redefined it in line 3. I'm guessing this is the
> problem.

thanks for spotting the obvious errors, its my 2nd day programming
python in about 3 years.
fridrick, code should be workable with the exception of the
errors...thats the whole program

Thanks again for all the help problem fixed


From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul  9 10:24:19 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 09 Jul 2009 16:24:19 +0200
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <4a55fd80$0$9943$426a74cc@news.free.fr>

Nick a ?crit :
> I've seen a lot of posts on this problem, but none seems to help.
> Here is the code:
> /code
> 
> file = open(prefix1)

shadows the builtin 'file' type.


> text = file.readlines()
> len = len(text)

shadows the builtin 'len' function.

> fields = text[1].split()
> num_rows = int(fields[1])
> num_cols = int(fields[2])
> 
> U1_matrix = []
> 
> print fields
> print repr(fields)
> print len(fields)

And here's your problem - 'len' is now bound to the result of the 
previous call to len(text).

Hint : Python's functions, classes and modules are objects too, and 
don't live in a distinct namespace. So _don't_ use builtin's types / 
functions / etc names as identifiers.

HTH


From davea at ieee.org  Thu Jul  9 10:52:14 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 09 Jul 2009 10:52:14 -0400
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <4A56041E.6020206@ieee.org>

Nick wrote:
> I've seen a lot of posts on this problem, but none seems to help.
> Here is the code:
> /code
>
> file = open(prefix1)
> text = file.readlines()
> len = len(text)
> fields = text[1].split()
> num_rows = int(fields[1])
> num_cols = int(fields[2])
>
> U1_matrix = []
>
> print fields
> print repr(fields)
> print len(fields)
>
> for line in text[2: num_rows+2]:
>     fields = line.split()
> #    print "fields", fields, line
>     for i in range(len(fields)):
>         fields[i] = float(fields[i])
>     U1_matrix.append(fields)
>
> /*code
>
> prefix is a space/line delimited ascii file that represents a 2D
> matrix.  i'm trying to read in 2 matrices from different files, strip
> away the header stuff and then take the dot product of the 2
> matrices.  any help is much appreciated.
>
> thanks,
> nick
>
>   
You have at least two problems with that code, one of which is causing 
your symptom.

Both 'file' and 'len' are defined in the standard library, and shouldn't 
be redefined in your code.  And your problem is that after you redefined 
'len', you then tried to use it in its original meaning.


Rename those two and you'll get further.

And it would have saved lots of time for lots of people if you included 
sample data and the actual error message, marking where in your code it 
occurs.  Once you know it's complaining about the len() call, it's not 
too hard to figure out that the problem was you rebound the len 
attribute from a function to an integer.

Traceback (most recent call last):
  File "M:\Programming\Python\sources\dummy\echo2.py", line 21, in <module>
    print len(fields)
TypeError: 'int' object is not callable


DaveA


From jcd at sdf.lonestar.org  Thu Jul  9 11:15:41 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Thu, 09 Jul 2009 11:15:41 -0400
Subject: count
In-Reply-To: <e4a20167-4c63-4ab3-baf2-be1f41c81fd8@a36g2000yqc.googlegroups.com>
References: <de8b174b0907072310l2572026bq62bef453b853c795@mail.gmail.com>
	<mailman.2829.1247043839.8015.python-list@python.org>
	<050094ea-faf4-4e03-875d-9c2c63090a89@y17g2000yqn.googlegroups.com>
	<h32sb5$eoq$1@panix3.panix.com> <7xbpnuzw4u.fsf@ruckus.brouhaha.com>
	<mailman.2865.1247105487.8015.python-list@python.org>
	<e4a20167-4c63-4ab3-baf2-be1f41c81fd8@a36g2000yqc.googlegroups.com>
Message-ID: <1247152541.3694.45.camel@aalcdl07>

Bearophile wins!  (This only times the loop itself.  It doesn't check
for __len__)

summer:5
0:00:00.000051
bearophile:5
0:00:00.000009
summer:50
0:00:00.000030
bearophile:50
0:00:00.000013
summer:500
0:00:00.000077
bearophile:500
0:00:00.000053
summer:5000
0:00:00.000575
bearophile:5000
0:00:00.000473
summer:50000
0:00:00.005583
bearophile:50000
0:00:00.004625
summer:500000
0:00:00.055834
bearophile:500000
0:00:00.046137
summer:5000000
0:00:00.426734
bearophile:5000000
0:00:00.349573
summer:50000000
0:00:04.180920
bearophile:50000000
0:00:03.652311
summer:500000000
0:00:42.647885
bearophile: 500000000
0:00:35.190550

On Thu, 2009-07-09 at 04:04 -0700, Bearophile wrote:
> Paul Rubin:
> > print x, sum(1 for _ in g)
> 
> Don't use that, use my function :-) If g has a __len__ you are wasting
> time. And sum(1 ...) is (on my PC) slower.
> 
> 
> J. Clifford Dyer:
> > if __name__ == '__main__':
> >     test_func(summer, 10000000)
> >     test_func(tupler, 10000000)
> >     test_func(summer, 100000000)
> >     test_func(tupler, 100000000)
> 
> Have you forgotten my function?
> 
> Bye,
> bearophile



From ethan at stoneleaf.us  Thu Jul  9 11:16:30 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 09 Jul 2009 08:16:30 -0700
Subject: tough-to-explain Python
In-Reply-To: <007075aa$0$9711$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>
	<007075aa$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <4A5609CE.70807@stoneleaf.us>

Steven D'Aprano wrote:
> 
> There is some evidence that 30-60% of people simply cannot learn to 
> program, no matter how you teach them:
> 
> http://www.codinghorror.com/blog/archives/000635.html
> http://www.cs.mdx.ac.uk/research/PhDArea/saeed/
> 
> I'm sympathetic to the idea, but not entirely convinced. Perhaps the 
> problem isn't with the students, but with the teachers, and the 
> languages: 
> 
> http://www.csse.monash.edu.au/~damian/papers/PDF/SevenDeadlySins.pdf
> 
> (My money is that it's a little of both.)
> 
> 

Very interesting articles.  Not suprising (to me, at least) -- everybody 
has their strengths and weaknesses.  I will never be, and could never 
have been, any kind of sports person;  I don't have the right 
personality to be a good people person;  I don't have the knack for 
writing stories.  Not everyone can do anything, or even many things.

~Ethan~


From fridrik at pyth.net  Thu Jul  9 11:30:35 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 15:30:35 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>
Message-ID: <391EDF07-7FCE-4DD2-B510-1EBA7A70D36A@pyth.net>

Previously, I wrote:
>> P.S. While this is a fairly obvious problem it's usually a good  
>> idea to post working code and a traceback when requesting help.

Nick wrote:
> thanks for spotting the obvious errors, its my 2nd day programming
> python in about 3 years.

I'm sorry, my saying it was obvious may have come off a little  
arrogant. My clumsily delivered point was that because it was a small  
snippet of code it didn't take much time to run through for someone  
who codes daily with Python. What you did there was a perfectly  
ordinary thing to do until experience teaches you how Python does  
things. :)

> fridrick, code should be workable with the exception of the
> errors...thats the whole program

You're right, I failed to say it explicitely but I was referring to  
the input file.  In some cases, albeit not this one, problems can  
exist in parsing gotchas.

Regards,
Fri?rik M?r

From robert.kern at gmail.com  Thu Jul  9 11:54:37 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 09 Jul 2009 10:54:37 -0500
Subject: PyQt GUI
In-Reply-To: <5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
Message-ID: <h353rt$kjh$1@ger.gmane.org>

On 2009-07-09 01:27, Helvin wrote:
> On Jul 9, 11:29 am, Robert Kern<robert.k... at gmail.com>  wrote:
>> On 2009-07-08 18:10, Helvin wrote:
>>
>>> Thanks for the fast replies! I will look into how to use VTK now.
>>> Where would I find VTK's explicit support for PyQt?
>> Wrapping/Python/vtk/qt4/ in the VTK sources.
>>
>>> Because I have installed VTK (using its installer) and pyVTK (using
>>> its setup.py file), but how do I actually use it in my code? According
>>> to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
>>> I have tried 'import vtk', but python can't find the vtk module.
>> Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
>> just a library for manipulating VTK files. The VTK Python bindings are part of
>> VTK's distribution itself. Exactly how did you install VTK? Did you compile it
>> yourself?
>
> You mean, when I download VTK, the VTK Python bindings come with it?
> I downloaded VTK from:http://vtk.org/files/release/5.4/

Exactly which file did you download? I don't think the vtk-5.4.x-win32.exe 
installers have the Python bindings. You will need to build VTK from sources.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From psimon at sonic.net  Thu Jul  9 12:02:34 2009
From: psimon at sonic.net (Paul Simon)
Date: Thu, 9 Jul 2009 09:02:34 -0700
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
Message-ID: <4a5615ba$0$95523$742ec2ed@news.sonic.net>


"Peter Otten" <__peter__ at web.de> wrote in message 
news:h3481q$d95$00$1 at news.t-online.com...
> Paul Simon wrote:
>
>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>> news:mailman.2863.1247095339.8015.python-list at python.org...
>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>> I have the "tkinter" problem and need some assistance to straighten it
>>> out.
>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>>> >"step
>>> 1" and cannot import "_tkinter." I do not have that file on my computer,
>>> but
>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>> This python stuff is great, but the documentation frequently
>>> feels like it is just a bit out of my grasp. I realize that all of this
>>> is free but I understand the instructions on the web page to repair only
>>> to the
>>> point of confusion. I'm not an expert. How do I modify my python
>>> configuration? Is there a file that needs to be edited? Which setup.py
>>> file
>>> do I use? Make? or python setup.py build and python setup.py install?
>>> Thanks. I appreciate your help.
>>
>> - How did you install Python?
>> - What Linux distro are you using?
>>
>> Cheers,
>> Chris
>> http://blog.rebertia.com
>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>> something from python.org and installed.  Not sure if it was tarball or
>> zip file.
>
> Zip or tar doesn't matter, you are installing "from source".
>
> Python has to find the necessary include files for tcl/tk. These are in
> separate packages that you have to install before you invoke Python's
> configure script.
>
> I don't know what they are called on your system -- look for tk-dev.rpm,
> tcl-dev.rpm or similar.
>
> You may run into the same problem with other modules like readline.
>
> Peter
>

Thank you Peter.  I understand what you are saying but don't know how to do 
it.  Although I installed from source, I followed a "cookbook" recipe. 
Could you tell me what files to execute, where they might be, and file 
arguments?  I'm just ignorant, not stupid. ;-).

Paul 




From nleioatt at gmail.com  Thu Jul  9 12:04:58 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 9 Jul 2009 09:04:58 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<75c32082-81ac-46e8-9ec2-195e63e3d829@y7g2000yqa.googlegroups.com>
	<mailman.2901.1247153447.8015.python-list@python.org>
Message-ID: <ed761421-f881-434c-b5f8-6ab98fce2191@d4g2000yqa.googlegroups.com>

no problem, i understand, i haven't coded anything in literally 2
years, but it was a simple and pretty obvious mistake.  thanks for all
your help,

nick


On Jul 9, 11:30 am, Fri?rik M?r J?nsson <frid... at pyth.net> wrote:
> Previously, I wrote:
> >> P.S. While this is a fairly obvious problem it's usually a good
> >> idea to post working code and a traceback when requesting help.
> Nick wrote:
> > thanks for spotting the obvious errors, its my 2nd day programming
> > python in about 3 years.
>
> I'm sorry, my saying it was obvious may have come off a little
> arrogant. My clumsily delivered point was that because it was a small
> snippet of code it didn't take much time to run through for someone
> who codes daily with Python. What you did there was a perfectly
> ordinary thing to do until experience teaches you how Python does
> things. :)
>
> > fridrick, code should be workable with the exception of the
> > errors...thats the whole program
>
> You're right, I failed to say it explicitely but I was referring to
> the input file.  In some cases, albeit not this one, problems can
> exist in parsing gotchas.
>
> Regards,
> Fri?rik M?r



From tkermode at gmail.com  Thu Jul  9 12:06:45 2009
From: tkermode at gmail.com (Tom Kermode)
Date: Thu, 9 Jul 2009 17:06:45 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <h34t9k$kp8$1@south.jnrs.ja.net>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
Message-ID: <da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>

Hi,

   Do you know a good way to avoid running into this problem?  It
makes sense to suggest not calling variables the same names as
built-in functions, but that's hard for a new python programmer who
doesn't already know what all the built-in functions are. Over time a
programmer will learn which names to avoid, but it's a bit of a
pitfall early on.

Cheers,
Tom



2009/7/9 Richard Brodie <R.Brodie at rl.ac.uk>:
>
> "Nick" <nleioatt at gmail.com> wrote in message
> news:e54c4461-c0b7-42fb-8542-cefd7bf5f89f at h18g2000yqj.googlegroups.com...
>
>> file = open(prefix1)
>> text = file.readlines()
>> len = len(text)
>
> You have redefined two built-in functions "file" and "len" in the first three lines.
> This is usually considered poor practice. Stick to meaningless variable names,
> it's safer (only joking).
>
> TypeError: 'int' object is not callable". This means that something you thought
> was a function is in fact an integer. It's helpful to post/look at the line number of
> the error; "how is this line failing", is much easier to answer than
> "how is my program failing".
>
> print len(fields)
>
> Here len is an integer, because you redefined it in line 3. I'm guessing this is the
> problem.
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.kiloday.com
http://www.fourstopspast.com


From R.Brodie at rl.ac.uk  Thu Jul  9 12:30:42 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Thu, 9 Jul 2009 17:30:42 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com><h34t9k$kp8$1@south.jnrs.ja.net>
	<mailman.2903.1247155607.8015.python-list@python.org>
Message-ID: <h355vi$n7j$1@south.jnrs.ja.net>


"Tom Kermode" <tkermode at gmail.com> wrote in message 
news:mailman.2903.1247155607.8015.python-list at python.org...

> Do you know a good way to avoid running into this problem?  It
> makes sense to suggest not calling variables the same names as
> built-in functions, but that's hard for a new python programmer who
> doesn't already know what all the built-in functions are.

No, but not redefining the ones you actually use is a good start.
Learning to understand the traceback is the more important lesson,
IMHO. It takes a while to tune into what error messages are trying
to tell you; even when you stop making newbie mistakes, you're
going to have to deal with runtime errors from time to time. 




From m at n.d  Thu Jul  9 12:32:41 2009
From: m at n.d (Broken)
Date: Thu, 9 Jul 2009 18:32:41 +0200
Subject: send keys to focused window
Message-ID: <MPG.24c0392b71e8a0eb989680@news.bintube.com>

Hi,
I am new to Python, and I'm miserably failing to send specific keys to 
(say) notepad.

Here is the scenario:
I have notepad open.
My python script is running in the background.
When I press ALT+a I want to intercept the keys and send "?"(ASCII code: 
ALT+0228) instead.

OS: Windows 7
Libraries used: pyHook, SendKeys, pyWin32

Here is my code:

###############################
# -*- coding: cp1252 -*-
import pythoncom, pyHook
from SendKeys import SendKeys

def OnKeyboardEvent(event):
    if event.Alt == 32:         #alt pressed
        if event.Ascii == 97:   #a pressed
            SendKeys("?")
        return False #don't pass to other handlers

# return True to pass the event to other handlers
    return True

# create a hook manager
hm = pyHook.HookManager()
# watch for all mouse events
hm.KeyDown = OnKeyboardEvent
# set the hook
hm.HookKeyboard()
# wait forever
pythoncom.PumpMessages()

###############################

It's largely copied from the pyhook example.
My problem is, I need to somehow disable ALT while sonding the key.

Please help :)


From h at realh.co.uk  Thu Jul  9 12:33:43 2009
From: h at realh.co.uk (Tony Houghton)
Date: Thu, 9 Jul 2009 17:33:43 +0100
Subject: Running a script to build docs from setup.py
Message-ID: <20090709173343.1784710d@realh.co.uk>

I want to write a setup.py script, using distutils, for a python library
called ROX-Lib2 (package name "rox"). The library includes a script to
build HTML documentation from the pydoc strings. I'd like to run that
script from setup.py but I don't know the best way to do that. I've
looked through the manual but I can't find any hooks in distutils for
generating files at install time other than extension modules and .pyc
files. Should I just run the script from somewhere in my setup.py before
calling distutils' setup function?

-- 
TH * http://www.realh.co.uk



From fridrik at pyth.net  Thu Jul  9 12:40:47 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 16:40:47 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
Message-ID: <FE4B2224-3848-4F74-94F7-58196C109670@pyth.net>

Tom Kermode wrote:
> Do you know a good way to avoid running into this problem?  It
> makes sense to suggest not calling variables the same names as
> built-in functions, but that's hard for a new python programmer who
> doesn't already know what all the built-in functions are.

One way is using a code checker like PyChecker[1]. This neat software  
for finding bugs will check for lots of other pitfalls too, but you  
can filter it down to what you need if you're only interested in this  
one.

I don't use an IDE, but this would seem like something for an IDE[2]  
to support if you're into that kind of magic.

Regards,
Fri?rik M?r

[1] http://pychecker.sourceforge.net/
[2] http://wiki.python.org/moin/IntegratedDevelopmentEnvironments

From __peter__ at web.de  Thu Jul  9 13:00:37 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 09 Jul 2009 19:00:37 +0200
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
Message-ID: <h357nj$903$00$1@news.t-online.com>

Paul Simon wrote:

> 
> "Peter Otten" <__peter__ at web.de> wrote in message
> news:h3481q$d95$00$1 at news.t-online.com...
>> Paul Simon wrote:
>>
>>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>>> news:mailman.2863.1247095339.8015.python-list at python.org...
>>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>>> I have the "tkinter" problem and need some assistance to straighten it
>>>> out.
>>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>>>> >"step
>>>> 1" and cannot import "_tkinter." I do not have that file on my
>>>> computer, but
>>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>>> This python stuff is great, but the documentation frequently
>>>> feels like it is just a bit out of my grasp. I realize that all of this
>>>> is free but I understand the instructions on the web page to repair
>>>> only to the
>>>> point of confusion. I'm not an expert. How do I modify my python
>>>> configuration? Is there a file that needs to be edited? Which setup.py
>>>> file
>>>> do I use? Make? or python setup.py build and python setup.py install?
>>>> Thanks. I appreciate your help.
>>>
>>> - How did you install Python?
>>> - What Linux distro are you using?
>>>
>>> Cheers,
>>> Chris
>>> http://blog.rebertia.com
>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not
>>> sure
>>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>> something from python.org and installed.  Not sure if it was tarball or
>>> zip file.
>>
>> Zip or tar doesn't matter, you are installing "from source".
>>
>> Python has to find the necessary include files for tcl/tk. These are in
>> separate packages that you have to install before you invoke Python's
>> configure script.
>>
>> I don't know what they are called on your system -- look for tk-dev.rpm,
>> tcl-dev.rpm or similar.
>>
>> You may run into the same problem with other modules like readline.
>>
>> Peter
>>
> 
> Thank you Peter.  I understand what you are saying but don't know how to
> do
> it.  Although I installed from source, I followed a "cookbook" recipe.
> Could you tell me what files to execute, where they might be, and file
> arguments?  I'm just ignorant, not stupid. ;-).
> 
> Paul

Once you have the necessary development packages for tcl/tk just go into the 
directory where you unzipped the source and

./configure
make
sudo make altinstall

Unfortunately I don't know the names of these packages nor how to install 
them, and Google didn't turn up anything useful.

If you don't get any additional answers here you may try a Mandriva forum 
since this is not a question that requires python knowlegde.

Peter



From duane.kaufman at gmail.com  Thu Jul  9 13:14:29 2009
From: duane.kaufman at gmail.com (TheSeeker)
Date: Thu, 9 Jul 2009 10:14:29 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
Message-ID: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>

Hi,

I am embarking on teaching myself Microsoft UI Automation using Python
as the scripting language.

I have asked some questions in the IronPython users group, but have
yet to get a response, so I thought I would broaden the audience by
asking here.

Specifically, I have a WinForms application I will be wanting to
automate. Does anyone have some Python examples of driving Microsoft
UI Automation they could share with me to get me started? The
structure of the UI automation classes etc. seem quite convoluted, and
I am having difficulty getting my brain wrapped around it.

Alternatives to Microsoft's UI Automation are welcome too, but I have
tried using winguiauto and watsup (along with AutoIt), and there seems
to be severe limitations when using these tools with WinForm
applications.

Thanks in advance,
Duane


From joshua at joshuakugler.com  Thu Jul  9 13:17:25 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Thu, 09 Jul 2009 09:17:25 -0800
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2tnpp$6if$1@ger.gmane.org> <h2up7a$epu$1@ger.gmane.org>
	<h30dfc$ke2$1@ger.gmane.org>
Message-ID: <h358n5$bn6$1@ger.gmane.org>

Joshua Kugler wrote:
> Sorry about that...since pysqlite and APSW are both discusses on the
> pysqlite list, I had made an incorrect assumption. Oops.

"are both discusses?"  Yeef, I must have been out of it.  Discussed, thank
you. :)

j



From usernet at ilthio.net  Thu Jul  9 13:18:49 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 09 Jul 2009 17:18:49 GMT
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
Message-ID: <ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>

On 2009-07-09, TheSeeker <duane.kaufman at gmail.com> wrote:
> Specifically, I have a WinForms application I will be wanting to
> automate. Does anyone have some Python examples of driving Microsoft
> UI Automation they could share with me to get me started? The
> structure of the UI automation classes etc. seem quite convoluted, and
> I am having difficulty getting my brain wrapped around it.

If you find a way to work through the UI using the keyboard (tabs, etc);
then, you can send it keyboard commands using WScript.WshShell.SendKeys():

http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx


From steve at REMOVE-THIS-cybersource.com.au  Thu Jul  9 13:20:14 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 09 Jul 2009 17:20:14 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
Message-ID: <007201bc$0$9710$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:

> The core abstractions of [mechanical] computation are just not that
> complicated.  You can teach them to anybody in about a half an hour,
> drunk. I have.

That's *easy*. Anyone can teach the most complicated and abstract 
principles of any topic at all drunk. What's hard is doing it sober.

http://stackoverflow.com/questions/63668/confessions-of-your-worst-wtf-
moment-what-not-to-do/350267#350267

or http://tinyurl.com/lur784


You'll excuse my skepticism about all these claims about how anyone can 
program, how easy it is to teach the fundamentals of Turing Machines and 
functional programming to anybody at all. Prove it. Where are your peer-
reviewed studies demonstrating such successes on randomly chosen people, 
not self-selected motivated, higher-than-average intelligence students?

In the real world, human beings are prone to serious cognitive biases and 
errors. Our brains are buggy. Take any list of reasoning fallacies, and 
you'll find the majority of people have difficulty avoid them. The first 
struggle is to get them to even accept that they *are* fallacies, but 
even once they have intellectually accepted it, getting them to live up 
to that knowledge in practice is much, much harder.

In fact I'd go further and say that *every single person*, no matter how 
intelligent and well-educated, will fall for cognitive biases and 
fallacious reasoning on a regular basis.

http://en.wikipedia.org/wiki/Cognitive_bias
http://en.wikipedia.org/wiki/Fallacy




-- 
Steven


From lie.1296 at gmail.com  Thu Jul  9 13:30:02 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 17:30:02 GMT
Subject: Cleaning up after failing to contructing objects
In-Reply-To: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
Message-ID: <uOp5m.3783$ze1.731@news-server.bigpond.net.au>

brasse wrote:
> Hello!
> I have been thinking about how write exception safe constructors in
> Python. By exception safe I mean a constructor that does not leak
> resources when an exception is raised within it. The following is an
> example of one possible way to do it:

First, your automatic cleaning Bar() silently pass an unitialized Bar()
into the calling code. When a code fails, it should fail as loud as
possible. Bar() should raises an Exception and the calling code should
turn into something like:

try:
    bar = Bar()
except Exception, e:
    print 'bar failed to construct'

And about the cleaning up, how about:

class CleanWrap(object):
    def __init__(self, cls, cleanup):
        self.cls = cls
        self.cleanup = cleanup
    def __call__(self, *args, **kargs):
        try:
            return self.cls(*args, **kargs)
        except:
            self.cleanup()
            raise

class Bar(object):
    def __init__(self):
        CleanWrappedFoo = CleanWrap(Foo, self.close)
        self.a = CleanWrappedFoo('a')
        self.b = CleanWrappedFoo('b', fail=True)
    def close(self):
        if hasattr(self, 'a'):
            self.a.close()
        if hasattr(self, 'b'):
            self.b.close()

try:
    bar = Bar()
except Exception, e:
    print 'Bar() failed to construct'

==========
My next attempt is pretty neat, using a totally different approach, see
the docstring for details:

class Foo1(object):
    def __init__(self, name, fail=False):
        self.name = name
        cls_name = self.__class__.__name__
        if not fail:
            print '%s.__init__(%s)' % (cls_name, self.name)
        else:
            print '%s.__init__(%s), FAIL' % (cls_name, self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)

class Foo2(object):
    def __init__(self, name, fail=False):
        self.name = name
        cls_name = self.__class__.__name__
        if not fail:
            print '%s.__init__(%s)' % (cls_name, self.name)
        else:
            print '%s.__init__(%s), FAIL' % (cls_name, self.name)
            raise Exception()

    def close(self):
        print '%s.close(%s)' % (self.__class__.__name__, self.name)


class CleanList(object):
    ''' Each CleanList() instance is rigged so that if exceptions happen
        in the same CleanList() instance's wrapped class, all objects
        created from the wrapped classes in the same CleanList()
        instance will be cleaned (see "Usage" for much better
        explanation).

        Usage:
        >>> cleaner = CleanList()
        >>> othercleaner = CleanList()
        >>> F = cleaner(F, F.close)
        >>> G = cleaner(G, G.close)
        >>> H = othercleaner(H, H.close)
        >>> a = F()
        >>> b = F()
        >>> c = G()
        >>> d = H()
        >>> cleaner.cleanall()

        cleaner.cleanall() will clean a, b, and c but not d
        exceptions in (F|G|H).__init__ will trigger
        cleaner.cleanall()

        Can be subclassed if you want to override the conditions
        that determines the triggering of cleanups
    '''
    def wrap(self, cls):
        ''' Wrapper factory that customizes Wrapper's subclass
        '''
        class Wrapper(cls):
            ''' Wraps the class' __init__ with cleanup guard.
                Subclasses cls to simulate cls as close as possible
            '''

            # change __class__ to make printing prettier
            # e.g. Foo1.__init__ instead of Wrapper.__init__
            # probably should be removed
            # I'm not sure of the side effects of changing __class__
            __class__ = cls

            def __init__(self_in, *args, **kargs):
                try:
                    sup = super(Wrapper, self_in)
                    ret = sup.__init__(*args, **kargs)
                except:
                    self.cleanall()
                    raise
                else:
                    self.add_to_list(cls, self_in)
                    return ret
        return Wrapper

    def __init__(self):
        self.cleaners = {}

    def __call__(self, cls, cleanup):
        ''' wraps the class constructor '''
        # cleanup, []:
        # cleanup is the function called to clean
        # [] is the object list for that `cleanup` function
        # may not be the best data structure, but it works...
        self.cleaners[cls] = cleanup, []
        return self.wrap(cls)

    def cleanall(self):
        ''' clean all objects '''
        for cleaner, insts in self.cleaners.values():
            for inst in insts:
                cleaner(inst)

    def add_to_list(self, cls, inst):
        ''' add objects to the cleanup list '''
        self.cleaners[cls][1].append(inst)

class Bar(object):
    def __init__(self):
        clist = CleanList()
        otherclist = CleanList()
        CleanFoo1 = clist(Foo1, Foo1.close)
        CleanFoo2 = clist(Foo2, Foo2.close)
        OtherCleanFoo1 = otherclist(Foo1, Foo1.close)
        self.a = CleanFoo1('a')
        self.b = CleanFoo2('b')
        # self.c should not be close()ed
        self.c = OtherCleanFoo1('c')
        self.d = CleanFoo1('d', fail=True)
        self.e = CleanFoo2('e')

class Car(object):
    def __init__(self):
        Clean = CleanList()
        CleanFoo1 = Clean(Foo1, Foo1.close)
        CleanFoo2 = Clean(Foo2, Foo2.close)
        self.a = CleanFoo1('a')
        self.b = CleanFoo2('b')
        self.c = CleanFoo1('c')
        self.d = CleanFoo2('d')

try:
    bar = Car()
except Exception, e:
    print e
    print 'Car() failed to construct'
print
try:
    bar = Bar()
except Exception, e:
    print e
    print 'Bar() failed to construct'


From sebastian.schabe at gmx.de  Thu Jul  9 13:34:59 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Thu, 09 Jul 2009 19:34:59 +0200
Subject: Concatenating images (numpy arrays), but they look like HSV images
Message-ID: <4a5629ba$1@news.fhg.de>

Hello everybody,

I want to concatenate 2 numpy array which in fact are RGB images:

def concat_images(im1,im2):
   rows1 = im1.shape[0]
   rows2 = im2.shape[0]

   if rows1 < rows2:
     im1 = concatenate((im1,zeros((rows2-rows1,im1.shape[1],3), int)), 
axis=0)
   elif rows1 > rows2:
     im2 = concatenate((im2,zeros((rows1-rows2,im2.shape[1],3), int)), 
axis=0)

   return concatenate((im1,im2), axis=1)

It's all working fine, except that the images when showing with pylab 
are somewhat interpreted as HSV images as it looks. The function zeros() 
must be responsible for that circumstance, because when the arrays have 
the same shape and are concatenated they appear as horizontally 
concatenated images as I expected.

Can someone help me with that?

Thanks a lot,
Basti


From lie.1296 at gmail.com  Thu Jul  9 13:35:19 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 17:35:19 GMT
Subject: property using a classmethod
In-Reply-To: <4a55e8e0$0$8041$426a34cc@news.free.fr>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
	<4a55e8e0$0$8041$426a34cc@news.free.fr>
Message-ID: <rTp5m.3784$ze1.643@news-server.bigpond.net.au>

Bruno Desthuilliers wrote:
> Lie Ryan a ?crit :
>> Emanuele D'Arrigo wrote:
> (snip)
>>> Ultimately all I want is a non-callable class-level attribute
>>> MyClass.myProperty that gives the result of MyClass.myClassMethod().
>>
>> This works like what you seem to want (it's ugly):
> 
> Ugly, indeed. And an extreme case of arbitrary overcomplexification too :-/
> 
> (snip rube goldberg code)
> 

Can't think of anything simpler than that without meddling with
descriptor. I'm not even sure descriptor can help here as it seems
descriptor needs an instance? (I've just skimmed it, so I may be wrong)

The ugliness of the code hints to two possible reasons:
- there should be a better way
- if there isn't an easier way, then something is wrong the class' design


From duane.kaufman at gmail.com  Thu Jul  9 13:36:50 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 10:36:50 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
Message-ID: <558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>

On Jul 9, 12:18?pm, Tim Harig <user... at ilthio.net> wrote:
> On 2009-07-09, TheSeeker <duane.kauf... at gmail.com> wrote:
>
> > Specifically, I have a WinForms application I will be wanting to
> > automate. Does anyone have some Python examples of driving Microsoft
> > UI Automation they could share with me to get me started? The
> > structure of the UI automation classes etc. seem quite convoluted, and
> > I am having difficulty getting my brain wrapped around it.
>
> If you find a way to work through the UI using the keyboard (tabs, etc);
> then, you can send it keyboard commands using WScript.WshShell.SendKeys():
>
> http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx

Thanks for the link.

Unfortunately, I need to be able to find out the contents of a few
text-boxes as well,
so SendKeys isn't all I need.

Thanks again,
Duane


From tjreedy at udel.edu  Thu Jul  9 13:40:01 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 09 Jul 2009 13:40:01 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <4A55F392.3080404@ieee.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
	<4A55F392.3080404@ieee.org>
Message-ID: <h35a1h$gus$1@ger.gmane.org>

Dave Angel wrote:
> m.reddy prasad reddy wrote:
>> can any one tell me how to write assembly language programs in 
>> python...if
>> no is there any other way to write the programs in python
>>
>> Reddi prasad reddy
>> ph.no:09958083797
>>
>>   
> Assembly language is a different programming language than Python.  You 
> can use both in the same process, much in the same way you can use C or 
> C++ with Python.  In fact, some of the system DLL's are written (partly) 
> in assembler, though mostly in C or C++.

It is possible that he meant how to write assembly *with* python.
Or how to translate python to assembly.

As it turns out, CPython translates Python to byte code and has a dis 
(assembly) module that produces very nice assembly code ;-)
So that is one answer to his question.

> You'll need to tell us what your real goal is.

Definitely.

tjr



From lie.1296 at gmail.com  Thu Jul  9 13:40:28 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 09 Jul 2009 17:40:28 GMT
Subject: older pythons
In-Reply-To: <4a55e1fb$0$1116$4fafbaef@reader3.news.tin.it>
References: <4a55ba0c$0$1105$4fafbaef@reader4.news.tin.it>
	<d7149ec1-50ff-422c-8c7a-7d637db62aea@h18g2000yqj.googlegroups.com>
	<4a55cb55$0$1116$4fafbaef@reader4.news.tin.it>
	<Bjk5m.3725$ze1.1139@news-server.bigpond.net.au>
	<4a55d6f7$0$1118$4fafbaef@reader3.news.tin.it>
	<Z6l5m.3737$ze1.1754@news-server.bigpond.net.au>
	<4a55e1fb$0$1116$4fafbaef@reader3.news.tin.it>
Message-ID: <gYp5m.3785$ze1.1005@news-server.bigpond.net.au>

superpollo wrote:
> Lie Ryan wrote:
>> superpollo wrote:
>>
>>> Lie Ryan wrote:
>>>
>>>
>>>> AFAIK, no major linux distributions have officially ported to python
>>>> 3.x.
>>>
>>> http://packages.debian.org/experimental/python3.1
>>>
>> Note the word "experimental"
> 
> i noticed. isn't experimental official? i thought it was...

Official as in "official release"?


From Scott.Daniels at Acm.Org  Thu Jul  9 13:40:58 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Thu, 09 Jul 2009 10:40:58 -0700
Subject: property using a classmethod
In-Reply-To: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
Message-ID: <3dKdndiWOZRutMvXnZ2dnUVZ_gFi4p2d@pdx.net>

Emanuele D'Arrigo wrote:
> class MyClass(object):
>     @classmethod
>     def myClassMethod(self):
>          print "ham"
>      myProperty = property(myClassMethod, None, None)
> 
> ... doesn't work and returns a TypeError: .... So, how do I do this?
> Ultimately all I want is a non-callable class-level attribute
> MyClass.myProperty that gives the result of MyClass.myClassMethod().

properties affect instances, and classes are instances of types.
What you want is a new metaclass:

     class MyType(type):
         @property
         def demo(class_):
             return class_.a + 3

     class MyClass(object):
         __metaclass__ = MyType
         a = 5

     print MyClass.a, MyClass.demo

--Scott David Daniels
Scott.Daniels at Acm.Org


From rhodri at wildebst.demon.co.uk  Thu Jul  9 13:41:59 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 09 Jul 2009 18:41:59 +0100
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
Message-ID: <op.uws939iha8ncjz@gnudebst>

On Thu, 09 Jul 2009 17:06:45 +0100, Tom Kermode <tkermode at gmail.com> wrote:

> Hi,
>
>    Do you know a good way to avoid running into this problem?  It
> makes sense to suggest not calling variables the same names as
> built-in functions, but that's hard for a new python programmer who
> doesn't already know what all the built-in functions are. Over time a
> programmer will learn which names to avoid, but it's a bit of a
> pitfall early on.

It's only really a pitfall if you try to use the built-in after you've
redefined it.  That's the thing to keep an eye open for.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Thu Jul  9 13:42:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 09 Jul 2009 19:42:56 +0200
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
	<m27hyi9jof.fsf@cs.uu.nl>
	<cafc471d-e1c3-4024-8090-898408415d8f@t13g2000yqt.googlegroups.com>
Message-ID: <m23a95ah27.fsf@cs.uu.nl>

>>>>> Lacrima <Lacrima.Maxim at gmail.com> (L) wrote:

>L> Thank you for really useful and detailed explanation. Now I can test
>L> my code using Emacs.
>L> But I think it works for me in a little bit different way.
>L> My file contains only the print 'hello world'.
>L> If I have no python shell running, then:
>L> a) C-c RET opens *Python Output* buffer without any output and with
>L> 'Shell command succeeded with no output' message at the bottom
>L> b) C-c C-c opens *Python Output* with appropriate 'hello world'
>L> message.

>L> Then I run python shell with C-c ! command. And:
>L> a) C-c RET opens *Python* buffer and prints 'hello world' in the
>L> python shell
>L> b) C-c C-c gives the same result.

Which version of python-mode.el do you have? (Variable py-version)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From usernet at ilthio.net  Thu Jul  9 13:45:13 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 09 Jul 2009 17:45:13 GMT
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
Message-ID: <J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>

On 2009-07-09, DuaneKaufman <duane.kaufman at gmail.com> wrote:
> On Jul 9, 12:18?pm, Tim Harig <user... at ilthio.net> wrote:
>> On 2009-07-09, TheSeeker <duane.kauf... at gmail.com> wrote:
>> > Specifically, I have a WinForms application I will be wanting to
>> > automate. Does anyone have some Python examples of driving Microsoft
>> > UI Automation they could share with me to get me started? The
>> > structure of the UI automation classes etc. seem quite convoluted, and
>> > I am having difficulty getting my brain wrapped around it.
>> If you find a way to work through the UI using the keyboard (tabs, etc);
>> then, you can send it keyboard commands using WScript.WshShell.SendKeys():
>> http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx
> Unfortunately, I need to be able to find out the contents of a few
> text-boxes as well,
> so SendKeys isn't all I need.

Then you will need some way to import your application as an object so that
you can gain access to the methods and properties directly.  Using
IronPython you should be able to access anyting in the GAC.  If you
register your UI componets then you should be able to access them.  If not,
or using cpython, you might be able to do something like:

http://msdn.microsoft.com/en-us/library/fh1h056h(VS.71).aspx

to get a mashalled COM object.


From black.linen99 at gmail.com  Thu Jul  9 13:46:47 2009
From: black.linen99 at gmail.com (Alex Rosslyn)
Date: Thu, 9 Jul 2009 10:46:47 -0700 (PDT)
Subject: Colour of output text
Message-ID: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>

Hi,

I would like to learn a way of changing the colour of a particular
part of the output text. I've tried the following:

import os
os.system("color 17")
print "This should be white on blue"

But that command changes the colour of ALL the text and the whole
background. What i'm trying to do is simple: Change a single part (A
letter, a word, a phrase) of the output text.

Is there a way of doing this?

Thanks in advance,

~~A.Rosslyn


From tjreedy at udel.edu  Thu Jul  9 13:49:36 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 09 Jul 2009 13:49:36 -0400
Subject: tkinter problem
In-Reply-To: <4a5615ba$0$95523$742ec2ed@news.sonic.net>
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>	<mailman.2863.1247095339.8015.python-list@python.org>	<4a5536d4$0$95520$742ec2ed@news.sonic.net>	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
Message-ID: <h35ajf$i71$1@ger.gmane.org>

Paul Simon wrote:
> "Peter Otten" <__peter__ at web.de> wrote in message 
> news:h3481q$d95$00$1 at news.t-online.com...
>> Paul Simon wrote:
>>

>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
>>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>> something from python.org and installed.  Not sure if it was tarball or
>>> zip file.
>> Zip or tar doesn't matter, you are installing "from source".
>>
>> Python has to find the necessary include files for tcl/tk. These are in
>> separate packages that you have to install before you invoke Python's
>> configure script.
>>
>> I don't know what they are called on your system -- look for tk-dev.rpm,
>> tcl-dev.rpm or similar.
>>
>> You may run into the same problem with other modules like readline.
>>
>> Peter
>>
> 
> Thank you Peter.  I understand what you are saying but don't know how to do 
> it.  Although I installed from source, I followed a "cookbook" recipe. 
> Could you tell me what files to execute, where they might be, and file 
> arguments?  I'm just ignorant, not stupid. ;-).

Is there a Mandriva list where you can ask such distribution-specific 
questions?



From usernet at ilthio.net  Thu Jul  9 13:53:12 2009
From: usernet at ilthio.net (Tim Harig)
Date: Thu, 09 Jul 2009 17:53:12 GMT
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
Message-ID: <c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com>

On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
> I would like to learn a way of changing the colour of a particular
> part of the output text. I've tried the following

http://catb.org/esr/faqs/smart-questions.html

> import os
> os.system("color 17")
> print "This should be white on blue"

I assume that you are on Windows?

> But that command changes the colour of ALL the text and the whole
> background. What i'm trying to do is simple: Change a single part (A
> letter, a word, a phrase) of the output text.

If you are on Windows, then there is an API accessing the Windows Console:

http://msdn.microsoft.com/en-us/library/ms682010(VS.85).aspx

On Unix operating systems this would be done through the curses interface:

http://docs.python.org/library/curses.html


From robert.kern at gmail.com  Thu Jul  9 14:08:08 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 09 Jul 2009 13:08:08 -0500
Subject: Concatenating images (numpy arrays), but they look like HSV images
In-Reply-To: <4a5629ba$1@news.fhg.de>
References: <4a5629ba$1@news.fhg.de>
Message-ID: <h35bma$m93$1@ger.gmane.org>

On 2009-07-09 12:34, Sebastian Schabe wrote:
> Hello everybody,
>
> I want to concatenate 2 numpy array which in fact are RGB images:
>
> def concat_images(im1,im2):
> rows1 = im1.shape[0]
> rows2 = im2.shape[0]
>
> if rows1 < rows2:
> im1 = concatenate((im1,zeros((rows2-rows1,im1.shape[1],3), int)), axis=0)
> elif rows1 > rows2:
> im2 = concatenate((im2,zeros((rows1-rows2,im2.shape[1],3), int)), axis=0)
>
> return concatenate((im1,im2), axis=1)
>
> It's all working fine, except that the images when showing with pylab
> are somewhat interpreted as HSV images as it looks. The function zeros()
> must be responsible for that circumstance, because when the arrays have
> the same shape and are concatenated they appear as horizontally
> concatenated images as I expected.
>
> Can someone help me with that?

Ask on the matplotlib mailing list.

   https://lists.sourceforge.net/lists/listinfo/matplotlib-users

Probably, you need to use zeros(..., dtype=uint8). When you use dtype=int, that 
will result in dtype=int arrays. I suspect that matplotlib is then interpreting 
that to mean that you want it to treat the input as scalar data (which it will 
pass through a colormap) rather than an RGB image.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From duane.kaufman at gmail.com  Thu Jul  9 14:09:03 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 11:09:03 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
Message-ID: <e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>

On Jul 9, 12:45?pm, Tim Harig <user... at ilthio.net> wrote:
> On 2009-07-09, DuaneKaufman <duane.kauf... at gmail.com> wrote:
>
> > On Jul 9, 12:18?pm, Tim Harig <user... at ilthio.net> wrote:
> >> On 2009-07-09, TheSeeker <duane.kauf... at gmail.com> wrote:
> >> > Specifically, I have a WinForms application I will be wanting to
> >> > automate. Does anyone have some Python examples of driving Microsoft
> >> > UI Automation they could share with me to get me started? The
> >> > structure of the UI automation classes etc. seem quite convoluted, and
> >> > I am having difficulty getting my brain wrapped around it.
> >> If you find a way to work through the UI using the keyboard (tabs, etc);
> >> then, you can send it keyboard commands using WScript.WshShell.SendKeys():
> >>http://msdn.microsoft.com/en-us/library/8c6yea83(VS.85).aspx
> > Unfortunately, I need to be able to find out the contents of a few
> > text-boxes as well,
> > so SendKeys isn't all I need.
>
> Then you will need some way to import your application as an object so that
> you can gain access to the methods and properties directly. ?Using
> IronPython you should be able to access anyting in the GAC. ?If you
> register your UI componets then you should be able to access them. ?If not,
> or using cpython, you might be able to do something like:
>
> http://msdn.microsoft.com/en-us/library/fh1h056h(VS.71).aspx
>
> to get a mashalled COM object.

Thanks again Tim.

I believe I probably mis-communicated my requirements (or at least,
was not explicit enough)

The application I wish to interact with is not my own, but an ERP
system GUI front-end.

With MS utilities like UISpy and the like, I can 'see' the controls in
the application, but I
do not seem to be able to manipulate them programatically, and I
believe it us simply due
to my not understanding of the UI Automation API.

Hence, my request for example code to boot-strap myself.

Thanks,
Duane


From steve at REMOVE-THIS-cybersource.com.au  Thu Jul  9 14:10:16 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 09 Jul 2009 18:10:16 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
Message-ID: <00720d76$0$9710$c3e8da3@news.astraweb.com>

On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:

>> persistent idea "out there" that programming is a very accessible
>> skill, like cooking or gardening, anyone can do it, and even profit
>> from it, monetarily or otherwise, etc., and to some extent I am
> 
> Programming is not like any other human activity.

In practice? In principle? Programming in principle is not the same as it 
is performed in practice.

But in either case, programming requires both the logical reasoning of 
mathematics and the creativity of the arts. Funnily enough, 
mathematicians will tell you that mathematics requires the same, and so 
will the best artists. I think mathematicians, engineers, artists, even 
great chefs, will pour scorn on your claim that programming is not like 
any other human activity.


[...]
> He talks about how "when all is said and done, the only thing computers
> can do for us is to manipulate symbols and produce results of such
> manipulations" and he emphasises the "uninterpreted" nature of
> mechanical symbol manipulation, i.e. that the machine is doing it
> mindlessly.

"Manipulate symbols" is so abstract as to be pointless. By that 
reasoning, I can build a "computer" consisting of a box open at the top. 
I represent a symbol by an object (say, a helium-filled balloon, or a 
stone), instead of a pattern of bits. I manipulate the symbol by holding 
the object over the box and letting go. If it flies up into the sky, that 
represents the symbol "Love is War", if it falls into the box, it 
represents the symbol "Strength is Blue", and if it just floats there, it 
represents "Cheddar Cheese". This is a deterministic, analog computer 
which manipulates symbols. Great.

And utterly, utterly useless. So what is my computer lacking that real 
computers have? When you have answered that question, you'll see why 
Dijkstra's claim is under-specified.



> Dijkstra[1]: "It is true that the student that has never manipulated
> uninterpreted formulae quickly realizes that he is confronted with
> something totally unlike anything he has ever seen before. But
> fortunately, the rules of manipulation are in this case so few and
> simple that very soon thereafter he makes the exciting discovery that he
> is beginning to master the use of a tool that, in all its simplicity,
> gives him a power that far surpasses his wildest dreams." [1]

What is an uninterpreted formula? If you don't interpret it, how can you 
distinguish it from random noise?


>> but maybe this idea is not entirely true...  Maybe, to get past the
>> most amateurish level, one has to, one way or another, come
>> face-to-face with bits, compilers, algorithms, and all the rest that
>> real computer scientists learn about in their formal training...
>>
>> kj
> 
> If you're never exposed to that constellation of concepts that underpins
> "mechanical symbol manipulation" you are adrift in a sea ("c", ha ha) of
> abstractions.
> 
> However, if you /are/ exposed to the "so few and simple" rules of
> manipulation the gates (no pun intended) to the kingdom are thrown wide.


What nonsense. The keys to the kingdom are the abstractions.

Here's an exercise for you, if you dare. It's not that difficult to 
remove the abstraction from integer addition, to explain it in terms of 
bit manipulation. If you prefer, you can write a Turing Machine instead.

Now try doing the same thing for Quicksort. Don't worry, we'll wait.

Once you've done that, let's see you implement a practical, scalable, non-
toy webserver as a Turing Machine.

No, it's not the fundamental operations that open the doors to the 
kingdom. It's the abstractions. The history of computing is to gain more 
and more power by leveraging better and better abstractions.


 
> On Jul 8, 9:10 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:

>> There is some evidence that 30-60% of people simply cannot learn to
>> program, no matter how you teach them:
>>
>> http://www.codinghorror.com/blog/archives/000635.html
>> http://www.cs.mdx.ac.uk/research/PhDArea/saeed/
...
> I don't buy it:


I'm not entirely convinced myself. It's plausible -- not everyone has got 
what it takes to be musically talented, or a great athlete, or a skilled 
surgeon, or a charismatic leader. Why should programming be the one high-
level intellectual skill that everybody is good at? Seems mighty 
implausible to me.

But I'm not sure that the distribution of skill is *fundamentally* bi-
modal. Maybe it is, maybe it isn't.


> I believe strongly that any normal person can learn to
> program, to manipulate symbols to create formulae that guide the machine
> in its uninterpreted symbol manipulation.

Most people don't manipulate abstract symbols *at all* -- even something 
as simple as:

"if x is to z as half y is to twice z, then x is the same as ____ y"
(fill in the blank)

will perplex most people.


> I think that "first hump" people can become "second hump" people but
> that it requires teaching them the foundations first, not confronting
> them with such incredible novelties as "a = b" and saying in effect,
> "here you go buddy, sink or swim."

The weakness of the paper is not that "a=b" is a novelty, but that it's 
dangerously familiar. All their students will have already seen "a=b" in 
the context of many years of mathematics. But that's not what it means in 
this context. So the risk is, they will be interpreting the symbols "a=b" 
in terms of mathematical equality, and getting confused.


> Quoting Dijkstra again [1]: "Before we part, I would like to invite you
> to consider the following way of doing justice to computing's radical
> novelty in an introductory programming course.
> 
> "On the one hand, we teach what looks like the predicate calculus, but
> we do it very differently from the philosophers. In order to train the
> novice programmer in the manipulation of uninterpreted formulae, we
> teach it more as boolean algebra, familiarizing the student with all
> algebraic properties of the logical connectives. To further sever the
> links to intuition, we rename the values {true, false} of the boolean
> domain as {black, white}.

This is supposed to be a good thing?

Oh my. It must be nice in that ivory tower, never having to deal with 
anyone who hasn't already been winnowed by years of study and self-
selection before taking on a comp sci course.

I don't think Dijkstra would have taken that suggestion seriously if he 
had to teach school kids instead of college adults.


... 
> (Did you read that last paragraph and think, "Well how the heck else are
> you supposed to program a computer if not in a computer language?"?  If
> so, well, that is kind of my point.)

No. What I thought was, how the hell are you supposed to manipulate 
symbols without a language to describe what sort of manipulations you can 
do?


>> > Maybe, to
>> > get past the most amateurish level, one has to, one way or another,
>> > come face-to-face with bits, compilers, algorithms, and all the rest
>> > that real computer scientists learn about in their formal training...
>>
>> The "No True Scotsman" fallacy.
>>
>> There's nothing amateurish about building software applications that
>> work, with well-designed interfaces and a minimum of bugs, even if
>> you've never heard of Turing Machines.
>>
>> --
>> Steven
> 
> I beg to differ. I recall a conversation with a co-worker who had
> "learned" to program using PHP.  Another co-worker and I were trying to
> convince him that there was a good reason to differentiate between hash
> tables and arrays. He didn't even know that they were different
> "things".

I shall manfully resist the urge to make sarcastic comments about 
ignorant PHP developers, and instead refer you to my earlier reply to you 
about cognitive biases. For extra points, can you identify all the 
fallacious reasoning in that paragraph of yours?


> I remember telling him, "between the metal and the desktop there is
> nothing but layers of abstraction.  We use different names precisely
> because of different behaviours."

But those abstractions just get in the way, according to you. He should 
be programming in the bare metal, doing pure symbol manipulation without 
language.


> He made "well-designed interfaces", but "amateurish" is about the nicest
> thing I would have called him.

Well, perhaps this is a failure of his profession, in that there isn't 
enough specialisation. If he is skilled with making interfaces, and 
unskilled with programming the backend, then he should work where his 
strength lies, instead of being insulted by somebody who has an entirely 
unjustified opinion about what "real programming" is.

If programming is symbol manipulation, then you should remember that the 
user interface is also symbol manipulation, and it is a MUCH harder 
problem than databases, sorting, searching, and all the other problems 
you learn about in academia. The user interface has to communicate over a 
rich but noisy channel using multiple under-specified protocols to a 
couple of pounds of meat which processes information using buggy 
heuristics evolved over millions of years to find the ripe fruit, avoid 
being eaten, and have sex. If you think getting XML was hard, that's 
*nothing* compared to user interfaces.

The fact that even bad UIs work at all is a credit to the heuristics, 
bugs and all, in the meat.


> As for "a minimum of bugs"... sigh. The "minimum of bugs" is zero, if
> you derive your "uninterpreted formulae" /correctly/.

And the secret of getting rich on the stock market is to buy low, sell 
high. Very true, and very pointless. How do you derive the formula 
correctly?

Do you have an algorithm to do so? If so, how do you know that algorithm 
is correct?


> Deriving provably
> correct "programs" should be what computer science and computer
> education are all about

That's impossible. Not just impractical, or hard, or subject to hardware 
failures, but impossible.

I really shouldn't need to raise this to anyone with pretensions of being 
a Computer Scientist and not just a programmer, but... try proving an 
arbitrary program will *halt*.

If you can't do that, then what makes you think you can prove all useful, 
necessary programs are correct?



> Again with Dijkstra[3]: "The prime paradigma of the pragmatic designer
> is known as "poor man's induction", i.e. he believes in his design as
> long as "it works", i.e. until faced with evidence to the contrary. (He
> will then "fix the design".) 

Yes, that is the only way it can be.


> The scientific designer, however, believes
> in his design because he understands why it will work under all
> circumstances. 

Really? Under *all* circumstances?

Memory failures? Stray cosmic radiation flipping bits? Noise in the power 
supply?

What's that you say? "That's cheating, the software designer can't be 
expected to deal with the actual reality of computers!!! We work in an 
abstract realm where computers never run out of memory, swapping never 
occurs, and the floating point unit is always correct!"

Fail enough. I don't want to make it too hard for you.

Okay, so let's compare the mere "pragmatic designer" with his provisional 
expectation that his code is correct, and Dijkstra's "scientific 
designer". He understands his code is correct. Wonderful!

Er, *how exactly* does he reach that understanding?

He reasons about the logic of the program. Great! I can do that. See, 
here's a proof that binary search is correct. How easy this is.

Now try it for some non-trivial piece of code. Say, the Linux kernel. 
This may take a while...

What guarantee do we have that the scientific designer's reasoning was 
correct? I mean, sure he is convinced he has reasoned correctly, but he 
would, wouldn't he? If he was unsure, he'd keep reasoning (or ask for 
help), until he was sure. But being sure doesn't make him correct. It 
just makes him sure.

So how do you verify the verification?

And speaking of binary search:

[quote]
I was shocked to learn that the binary search program that Bentley PROVED 
CORRECT and SUBSEQUENTLY TESTED [emphasis added] in Chapter 5 of 
"Programming Pearls" contains a bug. Once I tell you what the it is, you 
will understand why it escaped detection for two decades.
[end quote]

http://northernplanets.blogspot.com/2006/07/nearly-all-binary-searches-
are-broken.html

or http://tinyurl.com/nco6yv

Perhaps the "scientific designer" should be a little less arrogant, and 
take note of the lesson of real science: all knowledge is provisional and 
subject to correction and falsification.

Which really makes the "scientific designer" just a slightly more clever 
and effective "pragmatic designer", doesn't it?


> The transition from pragmatic to scientific design would
> indeed be a drastic change within the computer industry."

Given Dijkstra's definition of "scientific design", it certainly would. 
It would be as drastic a change as the discovery of Immovable Objects and 
Irresistible Forces would be to engineering, or the invention of a 
Universal Solvent for chemistry, or any other impossibility. 


> "Obviously no errors" is the goal to strive for, and I am comfortable
> calling anyone an amateur who prefers "no obvious errors."

It's not a matter of preferring no obvious errors, as understanding the 
limitations of reality. You simply can't do better than no obvious errors 
(although of course you can do worse) -- the only question is what you 
call "obvious".



-- 
Steven


From Lacrima.Maxim at gmail.com  Thu Jul  9 14:22:46 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Thu, 9 Jul 2009 11:22:46 -0700 (PDT)
Subject: Emacs Python-mode. Newbie problem.
References: <5332c16d-7e78-4f82-9da9-84f6d704d3df@c9g2000yqm.googlegroups.com>
	<m21vorar2o.fsf@cs.uu.nl>
	<379be2bd-6d79-498e-a90f-009ff7002559@q11g2000yqi.googlegroups.com>
	<m27hyi9jof.fsf@cs.uu.nl>
	<cafc471d-e1c3-4024-8090-898408415d8f@t13g2000yqt.googlegroups.com>
	<m23a95ah27.fsf@cs.uu.nl>
Message-ID: <53aaa579-e69a-43c3-b297-10c6ea6ebf35@b15g2000yqd.googlegroups.com>

On Jul 9, 8:42?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Lacrima <Lacrima.Ma... at gmail.com> (L) wrote:
> >L> Thank you for really useful and detailed explanation. Now I can test
> >L> my code usingEmacs.
> >L> But I think it works for me in a little bit different way.
> >L> My file contains only the print 'hello world'.
> >L> If I have no python shell running, then:
> >L> a) C-c RET opens *Python Output* buffer without any output and with
> >L> 'Shell command succeeded with no output' message at the bottom
> >L> b) C-c C-c opens *Python Output* with appropriate 'hello world'
> >L> message.
> >L> Then I run python shell with C-c ! command. And:
> >L> a) C-c RET opens *Python* buffer and prints 'hello world' in the
> >L> python shell
> >L> b) C-c C-c gives the same result.
>
> Which version of python-mode.el do you have? (Variable py-version)
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

py-version's value is "5.1.0"

Also maybe the problem is because I use Emacs version 21.4.1. But I
can't change it to 22, because I access Emacs via SSH on some shared
hosting service.

With regards, Max.


From ptmcg at austin.rr.com  Thu Jul  9 14:29:12 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Thu, 9 Jul 2009 11:29:12 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
Message-ID: <d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com>

On Jul 9, 1:09?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
> The application I wish to interact with is not my own, but an ERP
> system GUI front-end.
>

I have used pywinauto to drive a Flash game running inside of an
Internet Explorer browser - that's pretty GUI!

-- Paul


From duane.kaufman at gmail.com  Thu Jul  9 14:50:45 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 11:50:45 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
	<d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com>
Message-ID: <ff67eeab-48d1-40a5-8870-666944c8c7f2@q11g2000yqi.googlegroups.com>

On Jul 9, 1:29?pm, Paul McGuire <pt... at austin.rr.com> wrote:
> On Jul 9, 1:09?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
>
> > The application I wish to interact with is not my own, but an ERP
> > system GUI front-end.
>
> I have used pywinauto to drive a Flash game running inside of an
> Internet Explorer browser - that's pretty GUI!
>
> -- Paul

Hi,

Could you share some code examples?

Thanks,
Duane (duanek (at) chorus (dot) net)


From fridrik at pyth.net  Thu Jul  9 14:57:47 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Thu, 9 Jul 2009 18:57:47 +0000
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <op.uws939iha8ncjz@gnudebst>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<h34t9k$kp8$1@south.jnrs.ja.net>
	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>
	<op.uws939iha8ncjz@gnudebst>
Message-ID: <9DBED98B-8B7A-45DC-9177-D3E97B878AAF@pyth.net>

Hi Rhodri,

> It's only really a pitfall if you try to use the built-in after you've
> redefined it.  That's the thing to keep an eye open for.

You're right, but in cases where you're editing a codebase which you  
didn't author entirely by yourself you may not be aware of that.

That said, if the codebase you're working on is structured (short,  
concise methods) you should be working with small, consumable scopes  
you can inhale in entirety before modifying.

Regards,
Fri?rik M?r

From dns4 at cornell.edu  Thu Jul  9 15:08:29 2009
From: dns4 at cornell.edu (David Smith)
Date: Thu, 09 Jul 2009 15:08:29 -0400
Subject: tkinter problem
In-Reply-To: <4a5615ba$0$95523$742ec2ed@news.sonic.net>
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
Message-ID: <h35f78$pts$1@ruby.cit.cornell.edu>

Paul Simon wrote:
> "Peter Otten" <__peter__ at web.de> wrote in message 
> news:h3481q$d95$00$1 at news.t-online.com...
>> Paul Simon wrote:
>>
>>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>>> news:mailman.2863.1247095339.8015.python-list at python.org...
>>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>>> I have the "tkinter" problem and need some assistance to straighten it
>>>> out.
>>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as in
>>>>> "step
>>>> 1" and cannot import "_tkinter." I do not have that file on my computer,
>>>> but
>>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>>> This python stuff is great, but the documentation frequently
>>>> feels like it is just a bit out of my grasp. I realize that all of this
>>>> is free but I understand the instructions on the web page to repair only
>>>> to the
>>>> point of confusion. I'm not an expert. How do I modify my python
>>>> configuration? Is there a file that needs to be edited? Which setup.py
>>>> file
>>>> do I use? Make? or python setup.py build and python setup.py install?
>>>> Thanks. I appreciate your help.
>>> - How did you install Python?
>>> - What Linux distro are you using?
>>>
>>> Cheers,
>>> Chris
>>> http://blog.rebertia.com
>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not sure
>>> exactly how I installed Python.  Originally I had installed 2.5 from RPM
>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>> something from python.org and installed.  Not sure if it was tarball or
>>> zip file.
>> Zip or tar doesn't matter, you are installing "from source".
>>
>> Python has to find the necessary include files for tcl/tk. These are in
>> separate packages that you have to install before you invoke Python's
>> configure script.
>>
>> I don't know what they are called on your system -- look for tk-dev.rpm,
>> tcl-dev.rpm or similar.
>>
>> You may run into the same problem with other modules like readline.
>>
>> Peter
>>
> 
> Thank you Peter.  I understand what you are saying but don't know how to do 
> it.  Although I installed from source, I followed a "cookbook" recipe. 
> Could you tell me what files to execute, where they might be, and file 
> arguments?  I'm just ignorant, not stupid. ;-).
> 
> Paul 
> 
> 

Just install the tkinter package from the Mandriva Linux Control
Center's Software Management system.  I just did it, doing a search for
tkinter brought it right up.  All done.

--David


From ethan at stoneleaf.us  Thu Jul  9 16:06:16 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 09 Jul 2009 13:06:16 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h33k3d$2uu$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
Message-ID: <4A564DB8.3050209@stoneleaf.us>

kj wrote:
> 
> My scientific code is jam-packed with assertions.  I can't count
> the number of times that one such lowly assertion saved me from a
> silent but potentially disastrous bug. 

Now imagine that asserts had been disabled for that run...

The issue is not "should you validate your inputs", the issue is "do you 
want your validation able to be turned off?"

~Ethan~


From sberry2a at gmail.com  Thu Jul  9 16:16:38 2009
From: sberry2a at gmail.com (Sean)
Date: Thu, 9 Jul 2009 13:16:38 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
Message-ID: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>

I have a huge list, 10,000,000+ items.  Each item is a dictionary with
fields used to sort the list.  When I have completed sorting I want to
grab a page of items, say 1,000 of them which I do easily by using
list_data[x:x+1000]

Now I want to add an additional key/value pair to each dictionary in
the list, incrementing them by 1 each time.  So, if I grabbed page 2
of the list I would get:

[{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
1002}, ...]

Any way to do that with list comprehension?  Any other good way to do
it besides iterating over the list?

Thanks


From sberry2a at gmail.com  Thu Jul  9 16:33:01 2009
From: sberry2a at gmail.com (Sean)
Date: Thu, 9 Jul 2009 13:33:01 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <a1dd02c8-ffee-4f3f-8788-9cabcb194a86@y10g2000prf.googlegroups.com>

On Jul 9, 1:16?pm, Sean <sberr... at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?
>
> Thanks

I was able to do this by doing the following:
page_data = [[start_position + 1 + n, x] for n, x in enumerate
(page_data)]

However, this creates a list of lists, each containing an int and a
dictionary.  I wanted to add it directly to the dictionary.  I can add
the key position to the dictionary when the data is created, but how
would I assign the value in a list comprehension?



From tn.pablo at gmail.com  Thu Jul  9 16:38:16 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 9 Jul 2009 15:38:16 -0500
Subject: Best way to add a "position" value to each item in a list
In-Reply-To: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <fdd00b510907091338y5838da5ap3edfa8545c357bc@mail.gmail.com>

Howdy,

On Thu, Jul 9, 2009 at 15:16, Sean<sberry2a at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>

I don't get it, what do you increment by one, the value of a given key
or the number of key/value pairs?  Also, if  the 'position' key is the
index of the item in the list, then I don't understand what you mean
by 'page'.  Could you tell us about the structure of these
dictionaries?

> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?
>
> Thanks
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Pablo Torres N.


From ptmcg at austin.rr.com  Thu Jul  9 16:41:17 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Thu, 9 Jul 2009 13:41:17 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
	<d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com> 
	<ff67eeab-48d1-40a5-8870-666944c8c7f2@q11g2000yqi.googlegroups.com>
Message-ID: <d6bc18b8-f74e-40cb-ba9f-1be8386f2fc6@s31g2000yqs.googlegroups.com>

On Jul 9, 1:50?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
> > I have used pywinauto to drive a Flash game running inside of an
> > Internet Explorer browser - that's pretty GUI!
>
> > -- Paul
>
> Hi,
>
> Could you share some code examples?
>
> Thanks,
> Duane (duanek (at) chorus (dot) net)

I just went on a brief fishing expedition through two disk backups,
and no luck.  I guess it's been a while since I worked on this.

The work I did was entirely graphical, which is to say, my script
interacted with the Flash program by using PIL to take image snapshots
of the window, and then sifting through the bitmap looking for the
status of a "time remaining" thermometer-style gauge in the game.
Then the script could click on X-Y coordinates within the window,
which would get picked up by the Flash game, and the script would
monitor the "time remaining" gauge some more, and so on.

I'm not sure how well pywinauto would work in allowing you to access
controls such as textboxes within a form.  I remember that I had to
access the IE window using a caption name, and then found the embedded
Flash program as an embedded control of some sort, again, I probably
needed to indicate that it was some sort of "Adobe.FlashWidget1"
object or something.

I may have another, older disk backup at home, I can look for it later
this evening.

-- Paul


From malaclypse2 at gmail.com  Thu Jul  9 16:49:22 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Thu, 9 Jul 2009 16:49:22 -0400
Subject: Best way to add a "position" value to each item in a list
In-Reply-To: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <16651e80907091349x409158b7sf62f7bbd0fb7c1a6@mail.gmail.com>

On Thu, Jul 9, 2009 at 4:16 PM, Sean<sberry2a at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?

Normally you wouldn't mutate the items in a list with a list
comprehension.  Instead, you would use a for loop, like this:

for idx,item in enumerate(my_list_of_dicts):
    item['position'] = idx

Is there a particular reason you want to do this with a list
comprehension?  Using a list comp means you're going to create an
extra copy of your 10 million item list, just so you can add a key to
each member, then (probably) throw away the original list.  It doesn't
seem like the right tool for the job here.

-- 
Jerry


From jcd at sdf.lonestar.org  Thu Jul  9 16:56:44 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Thu, 09 Jul 2009 16:56:44 -0400
Subject: tough-to-explain Python
In-Reply-To: <00720d76$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <1247173004.20204.0.camel@aalcdl07>

On Thu, 2009-07-09 at 18:10 +0000, Steven D'Aprano wrote:
> If programming is symbol manipulation, then you should remember that
> the 
> user interface is also symbol manipulation, and it is a MUCH harder 
> problem than databases, sorting, searching, and all the other
> problems 
> you learn about in academia. The user interface has to communicate
> over a 
> rich but noisy channel using multiple under-specified protocols to a 
> couple of pounds of meat which processes information using buggy 
> heuristics evolved over millions of years to find the ripe fruit,
> avoid 
> being eaten, and have sex. If you think getting XML was hard, that's 
> *nothing* compared to user interfaces.

+1 QOTW!  QOTM, even!






From sberry2a at gmail.com  Thu Jul  9 17:00:27 2009
From: sberry2a at gmail.com (Sean)
Date: Thu, 9 Jul 2009 14:00:27 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <58d94d82-3482-4429-9632-3255d2a85295@12g2000pri.googlegroups.com>

On Jul 9, 1:16?pm, Sean <sberr... at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?
>
> Thanks

I was able to do this by doing the following:
page_data = [[start_position + 1 + n, x] for n, x in enumerate
(page_data)]

However, this creates a list of lists, each containing an int and a
dictionary.  I wanted to add it directly to the dictionary.  I can add
the key position to the dictionary when the data is created, but how
would I assign the value in a list comprehension?



From pavlovevidence at gmail.com  Thu Jul  9 17:03:13 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 9 Jul 2009 14:03:13 -0700 (PDT)
Subject: Best way to add a "position" value to each item in a list
References: <929bf3f5-4413-4c46-8883-506322ce0b04@j9g2000prh.googlegroups.com>
Message-ID: <1bf2ab02-2a84-41a2-8156-9ec3ac7301c4@t13g2000yqt.googlegroups.com>

On Jul 9, 1:16?pm, Sean <sberr... at gmail.com> wrote:
> I have a huge list, 10,000,000+ items. ?Each item is a dictionary with
> fields used to sort the list. ?When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time. ?So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>
> Any way to do that with list comprehension? ?Any other good way to do
> it besides iterating over the list?


Not really, but if you want to avoid the delay in setting the
dictionary elements (I'm guessing that is why you don't want to
iterate over the list--and parenthetically it's not iterating over the
list but adding dictionary items that is driving the time, and that
cost is unavoidable), you should consider adding the position elements
on demand.  That is, instead of running a big loop once to add
position to all ten million elements, just run the loop on individual
pages.

def get_page(start,end):
    page = list_data[start:end]
    for i,item in enumerate(page):
        page['position'] = start+i
    return page


That might not work depending on what you are doing but you should
consider it.


Carl Banks


From torriem at gmail.com  Thu Jul  9 17:09:13 2009
From: torriem at gmail.com (Michael Torrie)
Date: Thu, 09 Jul 2009 15:09:13 -0600
Subject: Examples of Python driven Microsoft UI Automation wanted
In-Reply-To: <e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
Message-ID: <4A565C79.4020501@gmail.com>

DuaneKaufman wrote:
> With MS utilities like UISpy and the like, I can 'see' the controls in
> the application, but I
> do not seem to be able to manipulate them programatically, and I
> believe it us simply due
> to my not understanding of the UI Automation API.

You're probably better off using a free app like AutoIt3 rather than
roll your own.  AutoIt's scripting language isn't as nice as Python, but
it does the job and it turing-complete.

http://www.autoitscript.com/autoit3/


From thebrasse at gmail.com  Thu Jul  9 17:10:02 2009
From: thebrasse at gmail.com (=?ISO-8859-1?Q?Mattias_Br=E4ndstr=F6m?=)
Date: Thu, 9 Jul 2009 14:10:02 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<uOp5m.3783$ze1.731@news-server.bigpond.net.au>
Message-ID: <42fbcee1-61b2-4ba8-a50a-39c9c0d2fe9c@k19g2000yqn.googlegroups.com>

On Jul 9, 7:30?pm, Lie Ryan <lie.1... at gmail.com> wrote:
> brasse wrote:
> > Hello!
> > I have been thinking about how write exception safe constructors in
> > Python. By exception safe I mean a constructor that does not leak
> > resources when an exception is raised within it. The following is an
> > example of one possible way to do it:
>
> First, your automatic cleaning Bar() silently pass an unitialized Bar()
> into the calling code. When a code fails, it should fail as loud as
> possible. Bar() should raises an Exception and the calling code should
> turn into something like:
>
> try:
> ? ? bar = Bar()
> except Exception, e:
> ? ? print 'bar failed to construct'
>

I know, I missed that little detail. :-)

> And about the cleaning up, how about:
>
> class CleanWrap(object):
> ? ? def __init__(self, cls, cleanup):
> ? ? ? ? self.cls = cls
> ? ? ? ? self.cleanup = cleanup
> ? ? def __call__(self, *args, **kargs):
> ? ? ? ? try:
> ? ? ? ? ? ? return self.cls(*args, **kargs)
> ? ? ? ? except:
> ? ? ? ? ? ? self.cleanup()
> ? ? ? ? ? ? raise
>
> class Bar(object):
> ? ? def __init__(self):
> ? ? ? ? CleanWrappedFoo = CleanWrap(Foo, self.close)
> ? ? ? ? self.a = CleanWrappedFoo('a')
> ? ? ? ? self.b = CleanWrappedFoo('b', fail=True)
> ? ? def close(self):
> ? ? ? ? if hasattr(self, 'a'):
> ? ? ? ? ? ? self.a.close()
> ? ? ? ? if hasattr(self, 'b'):
> ? ? ? ? ? ? self.b.close()
>

I think this example adds about as much overhead as my original
example with the try block. Ideally I would like to be able to write
my classes in the most straight forward manner possible. In my mind
that would be something like a naive constructor and a close/dispose
method:

def __init__(self):
    self.a = Foo()
    self.b = Bar()

def close(self):
    self.a.close()
    self.b.close()

See my other post (the one with the decorator named safe) in this
thread for an experiment I thought was promising for a while. However
there are some some use cases it has to cover to be useful:

(1) References to objects owned by someone else
def __init__(self, some_resource):
    self.not_my_responsibility = some_resource
    self.a = Foo()
    # If Foo.__init__ raises an exception self.not_my responsibility
should not be closed.

(2) Local objects
def __init__(self):
    x = Bar()
    self.a = Foo(x)
    # If Foo.__init__ raises an exception x should also be closed.

So far I have not been able to find any good solutions for (at least)
case 1. I'll give it a few more days, but I'm not  that hopeful. I
think that I will end up writing my classes very much like Bar in my
original post. If someone has any ideas for how to solve my two use
cases above with my decorator based approach I would really like to
hear them!

:.:: mattias


From torriem at gmail.com  Thu Jul  9 17:12:40 2009
From: torriem at gmail.com (Michael Torrie)
Date: Thu, 09 Jul 2009 15:12:40 -0600
Subject: Examples of Python driven Microsoft UI Automation wanted
In-Reply-To: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
Message-ID: <4A565D48.2060608@gmail.com>

TheSeeker wrote:
> Alternatives to Microsoft's UI Automation are welcome too, but I have
> tried using winguiauto and watsup (along with AutoIt), and there seems
> to be severe limitations when using these tools with WinForm
> applications.

http://www.autoitscript.com/forum/index.php?showtopic=96752 -- looks
like recent betas have much better support for WinForms, at least from
the change list.




From helvinlui at gmail.com  Thu Jul  9 17:19:23 2009
From: helvinlui at gmail.com (Helvin)
Date: Thu, 9 Jul 2009 14:19:23 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
	<mailman.2902.1247154895.8015.python-list@python.org>
Message-ID: <88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>

On Jul 10, 3:54?am, Robert Kern <robert.k... at gmail.com> wrote:
> On 2009-07-09 01:27, Helvin wrote:
>
>
>
>
>
> > On Jul 9, 11:29 am, Robert Kern<robert.k... at gmail.com> ?wrote:
> >> On 2009-07-08 18:10, Helvin wrote:
>
> >>> Thanks for the fast replies! I will look into how to use VTK now.
> >>> Where would I find VTK's explicit support for PyQt?
> >> Wrapping/Python/vtk/qt4/ in the VTK sources.
>
> >>> Because I have installed VTK (using its installer) and pyVTK (using
> >>> its setup.py file), but how do I actually use it in my code? According
> >>> to:http://www.nabble.com/embedded-VTK-window-in-PyQt-application-td23521...,
> >>> I have tried 'import vtk', but python can't find the vtk module.
> >> Then you have not installed VTK's Python bindings correctly. Note that pyVTK is
> >> just a library for manipulating VTK files. The VTK Python bindings are part of
> >> VTK's distribution itself. Exactly how did you install VTK? Did you compile it
> >> yourself?
>
> > You mean, when I download VTK, the VTK Python bindings come with it?
> > I downloaded VTK from:http://vtk.org/files/release/5.4/
>
> Exactly which file did you download? I don't think the vtk-5.4.x-win32.exe
> installers have the Python bindings. You will need to build VTK from sources.
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
> ? that is made terrible by our own mad attempt to interpret it as though it had
> ? an underlying truth."
> ? ?-- Umberto Eco

Yes, I think you are right. I did initially use the windows installer.
I didn't know that it did't have python bindings. I thought that if I
had pyVTK, then it would work. But it didn't. I am now building VTK
with sources according to this EXCELLENT tutorial that I have somehow
come across, at:
http://www-viz.tamu.edu/courses/viza658/08spring/tutorials/WinVTKInstall.html

It's for Windows XP, and I am on Vista, but I hope it will work. I
have worked my way through most of it now.

Thanks Robert!
Helvin


From mail.to.daniel.platz at googlemail.com  Thu Jul  9 18:03:36 2009
From: mail.to.daniel.platz at googlemail.com (tt-industries)
Date: Thu, 9 Jul 2009 15:03:36 -0700 (PDT)
Subject: Package for fast plotting of many data points in Python?
Message-ID: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>

Hi,

I am programming a oscilloscope module in Python. For this reason, I
want to plot very many data points as fast as possible. This can be
more than 100 000 at once. So far I have been using the ploting module
of wxPython. However, it becomes unstable for more than 25000 points.
Can someone recommend me a faster plotting library? It would be really
cool if one could embed this in wxPython. If someone has an idea I
would be very glad about answer.

With kind regards,

Daniel


From duane.kaufman at gmail.com  Thu Jul  9 18:10:10 2009
From: duane.kaufman at gmail.com (DuaneKaufman)
Date: Thu, 9 Jul 2009 15:10:10 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<mailman.2916.1247173965.8015.python-list@python.org>
Message-ID: <4be34b72-0961-4031-b943-82c9e7c95577@24g2000yqm.googlegroups.com>

On Jul 9, 4:12?pm, Michael Torrie <torr... at gmail.com> wrote:
> TheSeeker wrote:
> > Alternatives to Microsoft's UI Automation are welcome too, but I have
> > tried using winguiauto and watsup (along with AutoIt), and there seems
> > to be severe limitations when using these tools with WinForm
> > applications.
>
> http://www.autoitscript.com/forum/index.php?showtopic=96752-- looks
> like recent betas have much better support for WinForms, at least from
> the change list.

Hi,

Thanks for the information. Boy, you are away from a utility for a
couple of
weeks, and it starts growing things one needs!

Unfortunately, while it looks like AutoIt is gaining the ability to
'see' WinForms controls,
this beta doesn't seem to be able to retrieve the text say, in a
TextBox. Darn.

Thanks,
Duane


From stef.mientki at gmail.com  Thu Jul  9 18:26:09 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Fri, 10 Jul 2009 00:26:09 +0200
Subject: Package for fast plotting of many data points in Python?
In-Reply-To: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <4A566E81.5040503@gmail.com>

tt-industries wrote:
> Hi,
>
> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once.
At once is impossible ;-)
>  So far I have been using the ploting module
> of wxPython.
which plotting module ?
>  However, it becomes unstable for more than 25000 points.
>   
again what do you mean: 25000 points per ?
25000 points on a 1600 pixel width screen ?

Please try to be somewhat more specific.
cheers,
Stef
> Can someone recommend me a faster plotting library? It would be really
> cool if one could embed this in wxPython. If someone has an idea I
> would be very glad about answer.
>
> With kind regards,
>
> Daniel
>   



From tn.pablo at gmail.com  Thu Jul  9 18:49:48 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 9 Jul 2009 17:49:48 -0500
Subject: can i write a assemly language programs in python
In-Reply-To: <h35a1h$gus$1@ger.gmane.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com> 
	<4A55F392.3080404@ieee.org> <h35a1h$gus$1@ger.gmane.org>
Message-ID: <fdd00b510907091549p1416e82le07640632d168994@mail.gmail.com>

Or maybe he meant if you can have both Python and assembler code in
the same source file, but I haven't heard of it.  If what you are
trying to do is write a faster version of some part of your code, try
SWIG: http://www.swig.org/

Playing the guessing game is a time sink, and since nobody has done it
so far, I will: OP, please read
http://www.mikeash.com/getting_answers.html and
http://catb.org/esr/faqs/smart-questions.html

On Thu, Jul 9, 2009 at 12:40, Terry Reedy<tjreedy at udel.edu> wrote:
> Dave Angel wrote:
>>
>> m.reddy prasad reddy wrote:
>>>
>>> can any one tell me how to write assembly language programs in
>>> python...if
>>> no is there any other way to write the programs in python
>>>
>>> Reddi prasad reddy
>>> ph.no:09958083797
>>>
>>>
>>
>> Assembly language is a different programming language than Python. ?You
>> can use both in the same process, much in the same way you can use C or C++
>> with Python. ?In fact, some of the system DLL's are written (partly) in
>> assembler, though mostly in C or C++.
>
> It is possible that he meant how to write assembly *with* python.
> Or how to translate python to assembly.
>
> As it turns out, CPython translates Python to byte code and has a dis
> (assembly) module that produces very nice assembly code ;-)
> So that is one answer to his question.
>
>> You'll need to tell us what your real goal is.
>
> Definitely.
>
> tjr
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Pablo Torres N.


From milesck at umich.edu  Thu Jul  9 19:28:11 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Thu, 9 Jul 2009 19:28:11 -0400
Subject: Catching control-C
In-Reply-To: <n8m5m.3759$ze1.2493@news-server.bigpond.net.au>
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
	<n8m5m.3759$ze1.2493@news-server.bigpond.net.au>
Message-ID: <4F69EE56-6911-400D-B324-4F6CE3E789CF@umich.edu>

On Jul 9, 2009, at 9:20 AM, Lie Ryan wrote:

> Michael Mossey wrote:
>> I want to understand better what the "secret" is to responding to a
>> ctrl-C in any shape or form.
>
> Are you asking: "when would the python interpreter process
> KeyboardInterrupt?"
> ...
> In single threaded python program, the currently running thread is
> always the main thread (which can handle KeyboardInterrupt). I believe
> SIGINT is checked at every ticks. But SIGINT cannot interrupt atomic
> operations (i.e. it cannot interrupt long operations that takes a  
> single
> tick).

Some otherwise atomic single-bytecode operations (like large integer  
arithmetic) do manual checks for whether signals were raised (though  
that won't help at all if the operation isn't on the main thread).

> I believe a tick in python is equivalent to a single bytecode, but
> please correct me if I'm wrong.

Not all opcodes qualify as a tick.  In general, those opcodes that  
cause control to remain in the eval loop (and not make calls to other  
Python or C functions) don't qualify as ticks (but there are  
exceptions, e.g. so that while True: pass is interruptible).  In  
Python/ceval.c: PyEval_EvalFrameEx(), those opcodes that don't end in  
goto fast_next_opcode are ticks.

Please correct me if _I'm_ wrong! :)
-Miles



From sajmikins at gmail.com  Thu Jul  9 19:38:18 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 9 Jul 2009 19:38:18 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <50f98a4c0907091638u6ad23eaeo779a333a46860dc8@mail.gmail.com>

On Thu, Jul 9, 2009 at 3:17 AM, m.reddy prasad reddy<reddy.mrp at gmail.com> wrote:
>
> can any one tell me how to write assembly language programs in python...if
> no is there any other way to write the programs in python
>
> Reddi prasad reddy
> ph.no:09958083797
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>

Examine CorePy http://www.corepy.org

"CorePy is a complete system for developing machine-level programs in
Python. CorePy lets developers build and execute assembly-level
programs interactively from the Python command prompt, embed them
directly in Python applications, or export them to standard assembly
languages."

HTH,
~Simon


From xavier.benech at t-immersion.com  Thu Jul  9 19:39:07 2009
From: xavier.benech at t-immersion.com (=?ISO-8859-1?Q?Xavier_B=E9nech?=)
Date: Fri, 10 Jul 2009 01:39:07 +0200
Subject: sys.exit() and PyRun_SimpleFileExFlags()
Message-ID: <4A567F9B.80108@t-immersion.com>

Hi,

There is a behaviour I do not understand of PyRun_SimpleFileExFlags(), 
normally when it executes a python script containing a sys.exit(), it 
results by ending the calling application.

I have got this behaviour with PyRun_SimpleFileExFlags() when I call it 
from the main thread of a GUI application (so I use PyRun_FileExFlags() 
in this case).

But in another application when it is called 
(PyRun_SimpleFileExFlags())) from a working thread (not the main one) of 
a console application, everything just go fine without exiting the 
application nor the thread. It returns the exit code specified in 
sys.exit() just fine.

Last things, I am working on Windows. And for the story, I started to 
make a small function to wrap some embedded python script call using the 
simple way with PyRun_SimpleFileExFlags() for the second application, 
but when I integrate it in the first one (with GUI) got some problems 
(:)) so I redo things with a cleaner PyRun_FileExFlags() call.

So, my question is: why do I have different behaviour of 
PyRun_SimpleFileExFlags() in this two cases?

Regards,
Xavier Benech.



From bearophileHUGS at lycos.com  Thu Jul  9 19:49:10 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 9 Jul 2009 16:49:10 -0700 (PDT)
Subject: can i write a assemly language programs in python
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com> 
	<mailman.2921.1247182700.8015.python-list@python.org>
Message-ID: <4d8af709-e4c1-431e-9a43-7f0f0dd8f1a6@j32g2000yqh.googlegroups.com>

Simon Forman:
> Examine CorePyhttp://www.corepy.org
>
> "CorePy is a complete system for developing machine-level programs in
> Python. CorePy lets developers build and execute assembly-level
> programs interactively from the Python command prompt, embed them
> directly in Python applications, or export them to standard assembly
> languages."

I have never used CorePy yet, but it's an awesome project ^_^
With some care and work even Python programs can get fast enough :-)

Bye,
bearophile


From clp2 at rebertia.com  Thu Jul  9 19:54:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 16:54:23 -0700
Subject: Package for fast plotting of many data points in Python?
In-Reply-To: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <50697b2c0907091654l188ea9c1v6b568fdf1dc5e89@mail.gmail.com>

On Thu, Jul 9, 2009 at 3:03 PM,
tt-industries<mail.to.daniel.platz at googlemail.com> wrote:
> Hi,
>
> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once. So far I have been using the ploting module
> of wxPython. However, it becomes unstable for more than 25000 points.
> Can someone recommend me a faster plotting library? It would be really
> cool if one could embed this in wxPython. If someone has an idea I
> would be very glad about answer.

Don't know how fast it is or how well it integrates, but matplotlib is
probably worth considering:
http://matplotlib.sourceforge.net/

Cheers,
Chris
-- 
http://blog.rebertia.com


From sajmikins at gmail.com  Thu Jul  9 20:01:47 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 9 Jul 2009 20:01:47 -0400
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <50f98a4c0907091701q660fec7cxfe75315a4e72575b@mail.gmail.com>

On Thu, Jul 9, 2009 at 9:42 AM, Nick<nleioatt at gmail.com> wrote:
<snip>
> ? ?fields = line.split()
> ? ?for i in range(len(fields)):
> ? ? ? ?fields[i] = float(fields[i])


instead of the above code you could say:

fields = [float(n) for n in in line.split()]

Have fun getting back into python! :]  (A lot has changed in the last few years)
HTH,
~Simon


From http  Thu Jul  9 20:22:06 2009
From: http (Paul Rubin)
Date: 09 Jul 2009 17:22:06 -0700
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
Message-ID: <7xab3d9ykx.fsf@ruckus.brouhaha.com>

Nick <nleioatt at gmail.com> writes:
> text = file.readlines()
> len = len(text)
> fields = text[1].split()

Is that intended to split the first line of the file?  Remember
that arrays in python begin at index 0.


From marty.musatov at gmail.com  Thu Jul  9 21:03:31 2009
From: marty.musatov at gmail.com (Musatov)
Date: Thu, 9 Jul 2009 18:03:31 -0700 (PDT)
Subject: AP  -- MeAmI.org Paces Google
Message-ID: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>

Los Angeles (AP) --MeAmI.org now has users in 50 countries following
its adopted use in Pakistan.  The search engine has grown in
popularity 10,000 fold following its Beta test launch three months ago
in April, 2009. Supporters of the site claim it is better than rival
Google upon which platform it is based. Controversy arose after
MeAmI.org search code allowed users to search other users Google
results with no advertising. "It is truly an innovative thing we are
doing," said Founder and CEO, Martin Musatov. "Letting users search
the results of other Google users immediately results in a level of
accuracy and relevance above and beyond Google." Google changed their
API following the launch or MeAmI.org and explored the possibility of
blocking site access from MeAmI.org to Google search results but was
unable to do so. Critics of MeAmI.org say what it is doing is
tantamount to intellectual theft. When asked about this topper Musatov
exclaimed, "The Internet was made for people, not companies." An
analyst at Goldman Sachs says, requesting to remain anonymous,
"MeAmI.org has a strong presence in promoting itself as a vehicle for
global activism and to tell you the truth, this makes it much more
likely an acquisition target than potential intellectual property
violator." Google could not be reached for comment.


From ldo at geek-central.gen.new_zealand  Thu Jul  9 21:05:01 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Fri, 10 Jul 2009 13:05:01 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
Message-ID: <h3643t$3f5$6@lust.ihug.co.nz>

In message <h3291j$mfu$1 at reader1.panix.com>, kj wrote:

> .., Lundh writes:
> 
>   Assignment statements modify namespaces, not objects.

<counterexample>

    >>> a = [3]
    >>> b = a

These may indeed modify a namespace, not any object. However:

    >>> a[:] = [4]
    >>> a
    [4]
    >>> b
    [4]

What change has happened to the namespace in this case? None. Yet an object 
has changed.

</counterexample>



From ben+python at benfinney.id.au  Thu Jul  9 21:06:34 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 10 Jul 2009 11:06:34 +1000
Subject: Running a script to build docs from setup.py
References: <20090709173343.1784710d@realh.co.uk>
Message-ID: <87fxd5ny79.fsf@benfinney.id.au>

Tony Houghton <h at realh.co.uk> writes:

> I've looked through the manual but I can't find any hooks in distutils
> for generating files at install time other than extension modules and
> .pyc files. Should I just run the script from somewhere in my setup.py
> before calling distutils' setup function?

Indirectly related: Ian Bicking's article on using Python's ?setup.py?
as a ?Makefile? replacement:

    <URL:http://blog.ianbicking.org/pythons-makefile.html>

If one is writing a ?setup.py? anyway, I think it makes sense to use
that as the build program for the whole project if possible. Good
hunting!

-- 
 \     ?I have an answering machine in my car. It says, ?I'm home now. |
  `\  But leave a message and I'll call when I'm out.?? ?Steven Wright |
_o__)                                                                  |
Ben Finney


From scriber17 at aol.com  Thu Jul  9 21:07:55 2009
From: scriber17 at aol.com (The Masked Logician)
Date: Thu, 9 Jul 2009 18:07:55 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <8bbed30b-53e5-4558-8e50-fbc395221915@y10g2000prf.googlegroups.com>

On Jul 9, 6:03?pm, Musatov <marty.musa... at gmail.com> wrote:
> Los Angeles (AP) -- MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan. The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
> the results of other Google users immediately results in a level of
> accuracy and relevance above and beyond Google." Google changed their
> API following the launch or MeAmI.org and explored the possibility of
> blocking site access from MeAmI.org to Google search results but was
> unable to do so. Critics of MeAmI.org say what it is doing is
> tantamount to intellectual theft. When asked about this topper Musatov
> exclaimed, "The Internet was made for people, not companies." An
> analyst at Goldman Sachs says, requesting to remain anonymous,
> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> global activism and to tell you the truth, this makes it much more
> likely an acquisition target than potential intellectual property
> violator." Google could not be reached for comment.

Wow.


From ben+python at benfinney.id.au  Thu Jul  9 21:11:26 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 10 Jul 2009 11:11:26 +1000
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <87bpntnxz5.fsf@benfinney.id.au>

tt-industries <mail.to.daniel.platz at googlemail.com> writes:

> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once.

I think you will find good results using Numpy for your arrays of data
<URL:http://numpy.scipy.org/> and Matplotlib to plot those arrays
<URL:http://matplotlib.sourceforge.net/>.

-- 
 \        ?Ubi dubium, ibi libertas.? (?Where there is doubt, there is |
  `\                                                        freedom.?) |
_o__)                                                                  |
Ben Finney


From roy at panix.com  Thu Jul  9 21:16:09 2009
From: roy at panix.com (Roy Smith)
Date: Thu, 09 Jul 2009 21:16:09 -0400
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <roy-D93967.21160909072009@news.panix.com>

In article 
<0734dc45-d8a0-4f28-b945-f9e179f30f5c at h11g2000yqb.googlegroups.com>,
 tt-industries <mail.to.daniel.platz at googlemail.com> wrote:

> I am programming a oscilloscope module in Python.

Sigh.  I guess I'm showing my age, but I still can't get used to the idea 
that the right tool to build an oscilloscope is no longer a soldering iron.


From bcb at undisclosedlocation.net  Thu Jul  9 21:18:23 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Thu, 9 Jul 2009 20:18:23 -0500
Subject: AP  -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <xDw5m.33863$S16.1632@newsfe23.iad>

"Musatov" <marty.musatov at gmail.com> wrote in message 
news:fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42 at x6g2000prc.googlegroups.com...

[snip-a-rooney]

> violator." Google could not be reached for comment.

Possibly because they were laughing so hard they couldn't hear their cell 
phones ringing ...? 




From scriber17 at aol.com  Thu Jul  9 21:29:58 2009
From: scriber17 at aol.com (The Masked Logician)
Date: Thu, 9 Jul 2009 18:29:58 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<xDw5m.33863$S16.1632@newsfe23.iad>
Message-ID: <7657db2e-71b3-4a49-b70f-127e362824a2@x5g2000prf.googlegroups.com>

On Jul 9, 6:18?pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> "Musatov" <marty.musa... at gmail.com> wrote in message
>
> news:fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42 at x6g2000prc.googlegroups.com...
>
> [snip-a-rooney]
>
> > violator." Google could not be reached for comment.
>
> Possibly because they were laughing so hard they couldn't hear their cell
> phones ringing ...?

Thank you for your comment Bruce C. Baker. Are you aware you're dead?

http://wcc.dli.mt.gov/B/BAKER_BRUCE_SJ_DECISION.htm

http://MeAmI.org

"The Best Search Engine for Fat Dead Guys named Bruce"


From matt.dubins at sympatico.ca  Thu Jul  9 21:36:05 2009
From: matt.dubins at sympatico.ca (inkhorn)
Date: Thu, 9 Jul 2009 18:36:05 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big string?
Message-ID: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>

Hi all,

For one of my projects, I came across the need to check if one of many
items from a list of strings could be found in a long string.  I came
up with a pretty quick helper function to check this, but I just want
to find out if there's something a little more elegant than what I've
cooked up.  The helper function follows:

def list_items_in_string(list_items, string):
    for item in list_items:
        if item in string:
            return True
    return False

So if you define a list x = ['Blah','Yadda','Hoohoo'] and a string y =
'Yip yip yippee Blah' and you run list_items_in_string(x, y), it
should return True.

Any ideas how to make that function look nicer? :)

Matt Dubins


From david250 at videotron.ca  Thu Jul  9 21:41:53 2009
From: david250 at videotron.ca (David Bernier)
Date: Thu, 09 Jul 2009 21:41:53 -0400
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <h3669102pl7@news7.newsguy.com>

Musatov wrote:
> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan.  The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
[ snip ]

I wonder what _AP_ means ...

David Bernier


From clp2 at rebertia.com  Thu Jul  9 21:43:31 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 18:43:31 -0700
Subject: How to check if any item from a list of strings is in a big 
	string?
In-Reply-To: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <50697b2c0907091843m174a065dx86e5ca6c21776a63@mail.gmail.com>

On Thu, Jul 9, 2009 at 6:36 PM, inkhorn<matt.dubins at sympatico.ca> wrote:
> Hi all,
>
> For one of my projects, I came across the need to check if one of many
> items from a list of strings could be found in a long string. ?I came
> up with a pretty quick helper function to check this, but I just want
> to find out if there's something a little more elegant than what I've
> cooked up. ?The helper function follows:
>
> def list_items_in_string(list_items, string):
> ? ?for item in list_items:
> ? ? ? ?if item in string:
> ? ? ? ? ? ?return True
> ? ?return False
>
> So if you define a list x = ['Blah','Yadda','Hoohoo'] and a string y =
> 'Yip yip yippee Blah' and you run list_items_in_string(x, y), it
> should return True.
>
> Any ideas how to make that function look nicer? :)

any(substr in y for substr in x)

Note that any() was added in Python 2.5

Cheers,
Chris
-- 
http://blog.rebertia.com


From fridrik at pyth.net  Thu Jul  9 21:45:01 2009
From: fridrik at pyth.net (=?ISO-8859-1?Q?Fri=F0rik_M=E1r_J=F3nsson?=)
Date: Fri, 10 Jul 2009 01:45:01 +0000
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <8BCC0DC4-7ADB-496C-AE87-5C419656CD73@pyth.net>

I'll be the first to admit it.  The point of writing a fake story by  
Associated Press and publishing it on a programming mailing list is  
totally beyond me.

Confoundedly yours,
Fri?rik M?r

From scriber17 at aol.com  Thu Jul  9 21:48:17 2009
From: scriber17 at aol.com (The Masked Logician)
Date: Thu, 9 Jul 2009 18:48:17 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h3669102pl7@news7.newsguy.com>
Message-ID: <90319430-9fdf-4286-b19a-8b1a852f75a9@g7g2000prg.googlegroups.com>

On Jul 9, 6:41?pm, David Bernier <david... at videotron.ca> wrote:
> Musatov wrote:
> > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > its adopted use in Pakistan. ?The search engine has grown in
> > popularity 10,000 fold following its Beta test launch three months ago
> > in April, 2009. Supporters of the site claim it is better than rival
> > Google upon which platform it is based. Controversy arose after
> > MeAmI.org search code allowed users to search other users Google
> > results with no advertising. "It is truly an innovative thing we are
> > doing," said Founder and CEO, Martin Musatov. "Letting users search
>
> [ snip ]
>
> I wonder what _AP_ means ...
>
> David Bernier

1. Dec 16, 2008 ... "Staffers recognize the tough times, but they also
understand that quality journalism at AP means attracting and
retaining the best ...
www.google.com/.../afp/.../ALeqM5gSCzjMBFqxtXCVC-am3ve59koBYQ

2. Business Accounting and Bookkeeping question: What does AP mean?
many things inc. associated press.
wiki.answers.com/Q/What_does_AP_mean

Found: http://www.meami.org/?cx=000961116824240632825%3A5n3yth9xwbo&cof=FORID%3A9%3B+NB%3A1&ie=UTF-8&q=AP+means#943

3. David Bernier - Wikipedia, the free encyclopedia David Enrique
Bernier also known as "Kike" (born January 21, 1977) former Secretary
of Sports and Recreation of Puerto Rico as well as Executive Director
of ...
en.wikipedia.org/wiki/David_Bernier

Found: http://www.meami.org/?cx=000961116824240632825%3A5n3yth9xwbo&cof=FORID%3A9%3B+NB%3A1&ie=UTF-8&q=David+Bernier#913

http://MeAmI.org

"Use it to fend off assholes."


From aahz at pythoncraft.com  Thu Jul  9 22:00:21 2009
From: aahz at pythoncraft.com (Aahz)
Date: 9 Jul 2009 19:00:21 -0700
Subject: Opening a SQLite database in readonly mode
References: <79990c6b0907060505v73703134wd02cd15ba0d3da66@mail.gmail.com>
	<h2up7a$epu$1@ger.gmane.org> <h30dfc$ke2$1@ger.gmane.org>
	<mailman.2905.1247159861.8015.python-list@python.org>
Message-ID: <h367bl$2ot$1@panix3.panix.com>

In article <mailman.2905.1247159861.8015.python-list at python.org>,
Joshua Kugler  <joshua at joshuakugler.com> wrote:
>Joshua Kugler wrote:
>>
>> Sorry about that...since pysqlite and APSW are both discusses on the
>> pysqlite list, I had made an incorrect assumption. Oops.
>
>"are both discusses?"  Yeef, I must have been out of it.  Discussed, thank
>you. :)

Who's Yeef?  ;-)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From jason at powerpull.net  Thu Jul  9 22:06:35 2009
From: jason at powerpull.net (Jason S. Friedman)
Date: Fri, 10 Jul 2009 02:06:35 +0000
Subject: language analysis to enforce code standards
In-Reply-To: <mailman.9989.1246930194.8014.python-list@python.org>
References: <mailman.9989.1246930194.8014.python-list@python.org>
Message-ID: <4A56A22B.5050204@powerpull.net>

Hello, I administer the Informatica ETL tool at my company.  Part of 
that role involves creating and enforcing standards.  I want the 
Informatica developers to add comments to certain key objects and I want 
to be able to verify (in an automated fashion) that they have done so.

I cannot merely check for non-emptiness; that is trivial to circumvent. 
  On the other hand, I probably do not need to be able to catch 
developers who are determined to not create comments.  There are not too 
many of them and perhaps they will find it is easier to write a (useful) 
comment than to game the system.

Any thoughts on how I might proceed?  Stated plainly, how can I tell 
when a string more-or-less forms at least one phrase?


From marty.musatov at gmail.com  Thu Jul  9 22:14:08 2009
From: marty.musatov at gmail.com (Martin Musatov)
Date: Thu, 9 Jul 2009 19:14:08 -0700
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <8BCC0DC4-7ADB-496C-AE87-5C419656CD73@pyth.net>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<8BCC0DC4-7ADB-496C-AE87-5C419656CD73@pyth.net>
Message-ID: <cf9a0a8b0907091914n470e44e5y3c392e8fff71fe4c@mail.gmail.com>

Thank you.
Martin Musatov

2009/7/9 Fri?rik M?r J?nsson <fridrik at pyth.net>

> I'll be the first to admit it.  The point of writing a fake story by
> Associated Press and publishing it on a programming mailing list is totally
> beyond me.
>
> Confoundedly yours,
> Fri?rik M?r
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090709/39a5926c/attachment-0001.html>

From rogerb at rogerbinns.com  Thu Jul  9 22:15:00 2009
From: rogerb at rogerbinns.com (Roger Binns)
Date: Thu, 09 Jul 2009 19:15:00 -0700
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <h34dsu$a4j$1@lec.cs.unibo.it>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
Message-ID: <h36875$2bs$1@ger.gmane.org>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

jacopo mondi wrote:
> Hi all, I need to patch socketmodule.c (the _socket module) in order to
> add support to an experimental socket family.

You may find it considerably easier to use ctypes since that will avoid
the need for any patching.  You'll also be able to control how read and
write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
os.fdopen to convert your raw file descriptor into a Python file object
if appropriate.

If you do use ctypes then you'll only need to distribute pure Python
source code.

Roger
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkpWpCAACgkQmOOfHg372QQq0QCbB+rslUqK/AuUu0gA6N4m01Jo
C8IAn3EkzFKCyt/K5WiuCnw3jzORBQh5
=JCv+
-----END PGP SIGNATURE-----



From nobody at nowhere.com  Thu Jul  9 22:28:04 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 10 Jul 2009 03:28:04 +0100
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
Message-ID: <pan.2009.07.10.02.28.04.344000@nowhere.com>

On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:

> Nobody says you shouldn't check your data. Only that "assert" is not the  
> right way to do that.

"assert" is not the right way to check your *inputs*. It's a perfectly
reasonable way to check data which "should" be valid, as well as a way to
document what variables are supposed to contain.



From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 22:42:04 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 02:42:04 GMT
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
Message-ID: <pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>

On Fri, 10 Jul 2009 02:06:35 +0000, Jason S. Friedman wrote:

> Hello, I administer the Informatica ETL tool at my company.  Part of
> that role involves creating and enforcing standards.  I want the
> Informatica developers to add comments to certain key objects and I want
> to be able to verify (in an automated fashion) that they have done so.
> 
> I cannot merely check for non-emptiness; that is trivial to circumvent.
>   On the other hand, I probably do not need to be able to catch
> developers who are determined to not create comments.  There are not too
> many of them and perhaps they will find it is easier to write a (useful)
> comment than to game the system.
> 
> Any thoughts on how I might proceed?  Stated plainly, how can I tell
> when a string more-or-less forms at least one phrase?

Define "phrase".


if len(s) > 0:
    print "at least one character"
if len(s.split()) > 0:
    print "at least one word"
if len(s.split('\n') > 0:
    print "at least one line"



-- 
Steven


From timr at probo.com  Thu Jul  9 22:52:58 2009
From: timr at probo.com (Tim Roberts)
Date: Thu, 09 Jul 2009 19:52:58 -0700
Subject: IP Address Function
References: <sfu755dl3a035fr2ukp79oth06te8sg1an@4ax.com>
	<mailman.2811.1247018054.8015.python-list@python.org>
	<jjn855l7ers5mk1j03q2k0uuf0895inn3l@4ax.com>
	<m2d48bbh7h.fsf@cs.uu.nl>
	<cbqa55pvvueq3pk355kj846kcjiv0q7nai@4ax.com>
Message-ID: <k1bd555692idl987pauglkg87mmgsihj1q@4ax.com>

Fred Atkinson <fatkinson at mishmash.com> wrote:
>
>I wonder why they don't just have a function to return it instead of
>putting you through all of that?  

In CGI, EVERYTHING gets communicated through environment variables.  That
(and the stdin stream) is really the only option, since you get a new
process for every request.

The Python CGI module doesn't provide a wrapper function because this
information is just not useful.  Most corporate users sit behind proxies,
so everyone at the company appears to come from the same IP.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From nobody at nowhere.com  Thu Jul  9 22:53:57 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 10 Jul 2009 03:53:57 +0100
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <pan.2009.07.10.02.53.57.172000@nowhere.com>

On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:

> For one of my projects, I came across the need to check if one of many
> items from a list of strings could be found in a long string.

If you need to match many strings or very long strings against the same
list of items, the following should (theoretically) be optimal:

	r = re.compile('|'.join(map(re.escape,list_items)))
	...
	result = r.search(string)



From david250 at videotron.ca  Thu Jul  9 22:54:16 2009
From: david250 at videotron.ca (David Bernier)
Date: Thu, 09 Jul 2009 22:54:16 -0400
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <h36agp02ste@news7.newsguy.com>

Musatov wrote:
> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan.  The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
> the results of other Google users immediately results in a level of
> accuracy and relevance above and beyond Google." Google changed their
> API following the launch or MeAmI.org and explored the possibility of
> blocking site access from MeAmI.org to Google search results but was
> unable to do so. Critics of MeAmI.org say what it is doing is
> tantamount to intellectual theft. When asked about this topper Musatov
> exclaimed, "The Internet was made for people, not companies." An
> analyst at Goldman Sachs says, requesting to remain anonymous,
> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> global activism and to tell you the truth, this makes it much more
> likely an acquisition target than potential intellectual property
> violator." Google could not be reached for comment.

Mr. Musatov,  do you know who originally wrote the
article above?

Thank you.

David Bernier


From zac256 at gmail.com  Thu Jul  9 22:54:47 2009
From: zac256 at gmail.com (Zac Burns)
Date: Thu, 9 Jul 2009 19:54:47 -0700
Subject: psyco V2 beta2 benchmark
In-Reply-To: <h2nhhs$g5m$00$1@news.t-online.com>
References: <h2nhhs$g5m$00$1@news.t-online.com>
Message-ID: <333edbe80907091954u7451e11fhf9600d1e2549137c@mail.gmail.com>

Where do you get this beta? I heard that Psyco V2 is coming out but
can't find anything on their site to support this.

--
Zachary Burns
(407)590-4814
Aim - Zac256FL
Production Engineer (Digital Overlord)
Zindagi Games



On Sat, Jul 4, 2009 at 5:26 AM, larudwer<larudwer at freenet.de> wrote:
> just out of curiosity i've downloaded the latest Version of Psyco V2 Beta 2
> and run the benchmarks against the old Version of psyco 1.6
>
> Because it might be of common interest, i am posting the results here.
>
> My machine is a Pentium D 3.2 Ghz running Windows XP SP 3 and Python 2.6.2.
> Psyco V2 was built with 4.3.3-tdm-1 mingw32 with optimisation flags changed
> to -O3
>
>
> Benchmark ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? | avg. Base time | psyco 1.6 time
> | psyco 2.0 time | ratio ? ? | possible error +-
> time_anyall all_bool_genexp ? ? ? ? ? ? ? | 2.270 ? ? ? ? ?| 2.250
> | 2.420 ? ? ? ? ?| 0.930 ? ? | 8.3 %
> time_anyall all_bool_listcomp ? ? ? ? ? ? | 3.450 ? ? ? ? ?| 1.900
> | 1.910 ? ? ? ? ?| 0.995 ? ? | 0.0 %
> time_anyall all_genexp ? ? ? ? ? ? ? ? ? ?| 1.970 ? ? ? ? ?| 1.940
> | 2.160 ? ? ? ? ?| 0.898 ? ? | 9.6 %
> time_anyall all_listcomp ? ? ? ? ? ? ? ? ?| 3.485 ? ? ? ? ?| 1.660
> | 1.660 ? ? ? ? ?| 1.000 ? ? | 1.4 %
> time_anyall all_loop ? ? ? ? ? ? ? ? ? ? ?| 0.665 ? ? ? ? ?| 0.090
> | 0.090 ? ? ? ? ?| 1.000 ? ? | 4.4 %
> time_anyall any_bool_genexp ? ? ? ? ? ? ? | 2.215 ? ? ? ? ?| 2.130
> | 2.340 ? ? ? ? ?| 0.910 ? ? | 10.0 %
> time_anyall any_bool_listcomp ? ? ? ? ? ? | 3.620 ? ? ? ? ?| 1.930
> | 1.940 ? ? ? ? ?| 0.995 ? ? | 9.0 %
> time_anyall any_genexp ? ? ? ? ? ? ? ? ? ?| 1.985 ? ? ? ? ?| 1.920
> | 2.180 ? ? ? ? ?| 0.881 ? ? | 10.1 %
> time_anyall any_listcomp ? ? ? ? ? ? ? ? ?| 3.360 ? ? ? ? ?| 1.680
> | 1.680 ? ? ? ? ?| 1.000 ? ? | 8.0 %
> time_anyall any_loop ? ? ? ? ? ? ? ? ? ? ?| 0.660 ? ? ? ? ?| 0.090
> | 0.090 ? ? ? ? ?| 1.000 ? ? | 3.0 %
> time_builtins chr(i) ? ? ? ? ? ? ? ? ? ? ?| 2.420 ? ? ? ? ?| 0.010
> | 0.010 ? ? ? ? ?| 1.000 ? ? | 0.0 %
> time_builtins hash(i) ? ? ? ? ? ? ? ? ? ? | 1.280 ? ? ? ? ?| 0.370
> | 0.080 ? ? ? ? ?| 4.625 ? ? | 8.1 %
> time_builtins int(round(f)) ? ? ? ? ? ? ? | 2.635 ? ? ? ? ?| 1.510
> | 1.120 ? ? ? ? ?| 1.348 ? ? | 0.4 %
> time_builtins min ? ? ? ? ? ? ? ? ? ? ? ? | 0.535 ? ? ? ? ?| 0.520
> | 0.120 ? ? ? ? ?| 4.333 ? ? | 1.9 %
> time_builtins min_kw ? ? ? ? ? ? ? ? ? ? ?| 4.430 ? ? ? ? ?| 4.400
> | 0.160 ? ? ? ? ?| 27.500 ? ?| 0.5 %
> time_builtins ord(i) ? ? ? ? ? ? ? ? ? ? ?| 0.320 ? ? ? ? ?| 0.000
> | 0.000 ? ? ? ? ?| 1.000 ? ? | 6.5 %
> time_builtins pow ? ? ? ? ? ? ? ? ? ? ? ? | 0.345 ? ? ? ? ?| 0.230
> | 0.150 ? ? ? ? ?| 1.533 ? ? | 2.9 %
> time_builtins reduce ? ? ? ? ? ? ? ? ? ? ?| 0.735 ? ? ? ? ?| 0.710
> | 0.020 ? ? ? ? ?| 35.498 ? ?| 1.4 %
> time_builtins round(f) ? ? ? ? ? ? ? ? ? ?| 1.720 ? ? ? ? ?| 0.890
> | 0.400 ? ? ? ? ?| 2.225 ? ? | 1.2 %
> time_builtins sums ? ? ? ? ? ? ? ? ? ? ? ?| 0.180 ? ? ? ? ?| 0.180
> | 0.100 ? ? ? ? ?| 1.800 ? ? | 0.0 %
> time_fib matrix ? ? ? ? ? ? ? ? ? ? ? ? ? | 0.425 ? ? ? ? ?| 0.360
> | 0.360 ? ? ? ? ?| 1.000 ? ? | 2.3 %
> time_fib recursive ? ? ? ? ? ? ? ? ? ? ? ?| 0.000 ? ? ? ? ?| 0.000
> | 0.000 ? ? ? ? ?| 1.000 ? ? | 0.0 %
> time_fib takahashi ? ? ? ? ? ? ? ? ? ? ? ?| 0.410 ? ? ? ? ?| 0.320
> | 0.330 ? ? ? ? ?| 0.970 ? ? | 0.0 %
> time_generators call next just many times | 0.900 ? ? ? ? ?| 0.630
> | 0.970 ? ? ? ? ?| 0.649 ? ? | 4.3 %
> time_generators iterate just many times ? | 0.660 ? ? ? ? ?| 0.550
> | 0.950 ? ? ? ? ?| 0.579 ? ? | 3.1 %
> time_generators send and loop 1000 ? ? ? ?| 2.805 ? ? ? ? ?| 2.540
> | 0.060 ? ? ? ? ?| 42.333 ? ?| 9.8 %
> time_generators send call loop 1000 ? ? ? | 2.505 ? ? ? ? ?| 2.940
> | 0.060 ? ? ? ? ?| 48.999 ? ?| 10.9 %
> time_generators send just many times ? ? ?| 1.280 ? ? ? ? ?| 0.590
> | 0.980 ? ? ? ? ?| 0.602 ? ? | 3.1 %
> time_iter iter ? ? ? ? ? ? ? ? ? ? ? ? ? ?| 1.490 ? ? ? ? ?| 0.590
> | 0.440 ? ? ? ? ?| 1.341 ? ? | 5.5 %
> time_math floats ? ? ? ? ? ? ? ? ? ? ? ? ?| 2.910 ? ? ? ? ?| 1.500
> | 1.630 ? ? ? ? ?| 0.920 ? ? | 0.7 %
> time_properties method_get ? ? ? ? ? ? ? ?| 0.935 ? ? ? ? ?| 0.120
> | 0.130 ? ? ? ? ?| 0.923 ? ? | 1.1 %
> time_properties method_set ? ? ? ? ? ? ? ?| 1.005 ? ? ? ? ?| 0.170
> | 0.180 ? ? ? ? ?| 0.944 ? ? | 1.0 %
> time_properties property_get ? ? ? ? ? ? ?| 0.960 ? ? ? ? ?| 0.740
> | 0.100 ? ? ? ? ?| 7.400 ? ? | 2.1 %
> time_properties property_set ? ? ? ? ? ? ?| 1.020 ? ? ? ? ?| 0.920
> | 0.930 ? ? ? ? ?| 0.989 ? ? | 0.0 %
> time_properties pyproperty_get ? ? ? ? ? ?| 1.535 ? ? ? ? ?| 1.310
> | 0.140 ? ? ? ? ?| 9.357 ? ? | 0.7 %
> time_properties pyproperty_set ? ? ? ? ? ?| 1.030 ? ? ? ? ?| 0.920
> | 0.930 ? ? ? ? ?| 0.989 ? ? | 2.0 %
> time_subdist subdist(i) ? ? ? ? ? ? ? ? ? | 3.665 ? ? ? ? ?| 1.640
> | 6.140 ? ? ? ? ?| 0.267 ? ? | 0.8 %
> time_sums rounding ? ? ? ? ? ? ? ? ? ? ? ?| 0.800 ? ? ? ? ?| 0.790
> | 0.810 ? ? ? ? ?| 0.975 ? ? | 2.5 %
>
>
> Running new timings with
> C:\Programme\GNU\python26\lib\site-packages\psyco\_psyco.pyd Sat Jul 04
> 12:09:07 2009
>
> time_anyall ? ?: all_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.36 ? ? psyco:
> 2.42 ? ? ratio: ?0.97
> time_anyall ? ?: all_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.45 ? ? psyco:
> 1.91 ? ? ratio: ?1.80
> time_anyall ? ?: all_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 2.06 ? ? psyco:
> 2.16 ? ? ratio: ?0.95
> time_anyall ? ?: all_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.51 ? ? psyco:
> 1.66 ? ? ratio: ?2.11
> time_anyall ? ?: all_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.65 ? ? psyco:
> 0.09 ? ? ratio: ?7.03
> time_anyall ? ?: any_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.32 ? ? psyco:
> 2.34 ? ? ratio: ?0.99
> time_anyall ? ?: any_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.45 ? ? psyco:
> 1.94 ? ? ratio: ?1.78
> time_anyall ? ?: any_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 2.08 ? ? psyco:
> 2.18 ? ? ratio: ?0.96
> time_anyall ? ?: any_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.49 ? ? psyco:
> 1.68 ? ? ratio: ?2.08
> time_anyall ? ?: any_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.65 ? ? psyco:
> 0.09 ? ? ratio: ?7.05
> time_builtins ?: chr(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.42 ? ? psyco:
> 0.01 ? ? ratio: 197.40
> time_builtins ?: hash(i) ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 1.33 ? ? psyco:
> 0.08 ? ? ratio: 17.69
> time_builtins ?: int(round(f)) ? ? ? ? ? ? ? ? ?plain: ? 2.63 ? ? psyco:
> 1.12 ? ? ratio: ?2.36
> time_builtins ?: min ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.53 ? ? psyco:
> 0.12 ? ? ratio: ?4.28
> time_builtins ?: min_kw ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 4.44 ? ? psyco:
> 0.16 ? ? ratio: 28.58
> time_builtins ?: ord(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.33 ? ? psyco:
> 0.00 ? ? ratio: 123.57
> time_builtins ?: pow ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.34 ? ? psyco:
> 0.15 ? ? ratio: ?2.24
> time_builtins ?: reduce ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.74 ? ? psyco:
> 0.02 ? ? ratio: 40.93
> time_builtins ?: round(f) ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.73 ? ? psyco:
> 0.40 ? ? ratio: ?4.38
> time_builtins ?: sums ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.18 ? ? psyco:
> 0.10 ? ? ratio: ?1.80
> time_fib ? ? ? : matrix ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.42 ? ? psyco:
> 0.36 ? ? ratio: ?1.18
> time_fib ? ? ? : recursive ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.00 ? ? psyco:
> 0.00 ? ? ratio: 19.45
> time_fib ? ? ? : takahashi ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.41 ? ? psyco:
> 0.33 ? ? ratio: ?1.25
> time_generators: send call loop 1000 ? ? ? ? ? ?plain: ? 2.36 ? ? psyco:
> 0.06 ? ? ratio: 41.30
> time_generators: send and loop 1000 ? ? ? ? ? ? plain: ? 2.66 ? ? psyco:
> 0.06 ? ? ratio: 46.69
> time_generators: send just many times ? ? ? ? ? plain: ? 1.26 ? ? psyco:
> 0.98 ? ? ratio: ?1.29
> time_generators: iterate just many times ? ? ? ?plain: ? 0.67 ? ? psyco:
> 0.95 ? ? ratio: ?0.70
> time_generators: call next just many times ? ? ?plain: ? 0.88 ? ? psyco:
> 0.97 ? ? ratio: ?0.91
> time_iter ? ? ?: iter ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.53 ? ? psyco:
> 0.44 ? ? ratio: ?3.47
> time_math ? ? ?: floats ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.90 ? ? psyco:
> 1.63 ? ? ratio: ?1.78
> time_properties: method_get ? ? ? ? ? ? ? ? ? ? plain: ? 0.93 ? ? psyco:
> 0.13 ? ? ratio: ?7.22
> time_properties: method_set ? ? ? ? ? ? ? ? ? ? plain: ? 1.00 ? ? psyco:
> 0.18 ? ? ratio: ?5.61
> time_properties: property_get ? ? ? ? ? ? ? ? ? plain: ? 0.95 ? ? psyco:
> 0.10 ? ? ratio: ?9.26
> time_properties: property_set ? ? ? ? ? ? ? ? ? plain: ? 1.02 ? ? psyco:
> 0.93 ? ? ratio: ?1.09
> time_properties: pyproperty_get ? ? ? ? ? ? ? ? plain: ? 1.54 ? ? psyco:
> 0.14 ? ? ratio: 10.80
> time_properties: pyproperty_set ? ? ? ? ? ? ? ? plain: ? 1.04 ? ? psyco:
> 0.93 ? ? ratio: ?1.12
> time_subdist ? : subdist(i) ? ? ? ? ? ? ? ? ? ? plain: ? 3.68 ? ? psyco:
> 6.14 ? ? ratio: ?0.60
> time_sums ? ? ?: rounding ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.79 ? ? psyco:
> 0.81 ? ? ratio: ?0.98
>
>
> Running new timings with original psyco
>
> time_anyall ? ?: all_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.18 ? ? psyco:
> 2.25 ? ? ratio: ?0.97
> time_anyall ? ?: all_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.45 ? ? psyco:
> 1.90 ? ? ratio: ?1.82
> time_anyall ? ?: all_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 1.88 ? ? psyco:
> 1.94 ? ? ratio: ?0.97
> time_anyall ? ?: all_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.46 ? ? psyco:
> 1.66 ? ? ratio: ?2.09
> time_anyall ? ?: all_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.68 ? ? psyco:
> 0.09 ? ? ratio: ?7.34
> time_anyall ? ?: any_bool_genexp ? ? ? ? ? ? ? ?plain: ? 2.11 ? ? psyco:
> 2.13 ? ? ratio: ?0.99
> time_anyall ? ?: any_bool_listcomp ? ? ? ? ? ? ?plain: ? 3.79 ? ? psyco:
> 1.93 ? ? ratio: ?1.96
> time_anyall ? ?: any_genexp ? ? ? ? ? ? ? ? ? ? plain: ? 1.89 ? ? psyco:
> 1.92 ? ? ratio: ?0.98
> time_anyall ? ?: any_listcomp ? ? ? ? ? ? ? ? ? plain: ? 3.23 ? ? psyco:
> 1.68 ? ? ratio: ?1.92
> time_anyall ? ?: any_loop ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.67 ? ? psyco:
> 0.09 ? ? ratio: ?7.26
> time_builtins ?: chr(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.42 ? ? psyco:
> 0.01 ? ? ratio: 197.10
> time_builtins ?: hash(i) ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 1.23 ? ? psyco:
> 0.37 ? ? ratio: ?3.30
> time_builtins ?: int(round(f)) ? ? ? ? ? ? ? ? ?plain: ? 2.64 ? ? psyco:
> 1.51 ? ? ratio: ?1.75
> time_builtins ?: min ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.54 ? ? psyco:
> 0.52 ? ? ratio: ?1.03
> time_builtins ?: min_kw ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 4.42 ? ? psyco:
> 4.40 ? ? ratio: ?1.00
> time_builtins ?: ord(i) ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.31 ? ? psyco:
> 0.00 ? ? ratio: 116.56
> time_builtins ?: pow ? ? ? ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.35 ? ? psyco:
> 0.23 ? ? ratio: ?1.50
> time_builtins ?: reduce ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.73 ? ? psyco:
> 0.71 ? ? ratio: ?1.03
> time_builtins ?: round(f) ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.71 ? ? psyco:
> 0.89 ? ? ratio: ?1.91
> time_builtins ?: sums ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.18 ? ? psyco:
> 0.18 ? ? ratio: ?1.03
> time_fib ? ? ? : matrix ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.43 ? ? psyco:
> 0.36 ? ? ratio: ?1.19
> time_fib ? ? ? : recursive ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.00 ? ? psyco:
> 0.00 ? ? ratio: 19.28
> time_fib ? ? ? : takahashi ? ? ? ? ? ? ? ? ? ? ?plain: ? 0.41 ? ? psyco:
> 0.32 ? ? ratio: ?1.27
> time_generators: send call loop 1000 ? ? ? ? ? ?plain: ? 2.65 ? ? psyco:
> 2.94 ? ? ratio: ?0.90
> time_generators: send and loop 1000 ? ? ? ? ? ? plain: ? 2.95 ? ? psyco:
> 2.54 ? ? ratio: ?1.16
> time_generators: send just many times ? ? ? ? ? plain: ? 1.30 ? ? psyco:
> 0.59 ? ? ratio: ?2.23
> time_generators: iterate just many times ? ? ? ?plain: ? 0.65 ? ? psyco:
> 0.55 ? ? ratio: ?1.17
> time_generators: call next just many times ? ? ?plain: ? 0.92 ? ? psyco:
> 0.63 ? ? ratio: ?1.45
> time_iter ? ? ?: iter ? ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 1.45 ? ? psyco:
> 0.59 ? ? ratio: ?2.47
> time_math ? ? ?: floats ? ? ? ? ? ? ? ? ? ? ? ? plain: ? 2.92 ? ? psyco:
> 1.50 ? ? ratio: ?1.95
> time_properties: method_get ? ? ? ? ? ? ? ? ? ? plain: ? 0.94 ? ? psyco:
> 0.12 ? ? ratio: ?7.88
> time_properties: method_set ? ? ? ? ? ? ? ? ? ? plain: ? 1.01 ? ? psyco:
> 0.17 ? ? ratio: ?6.08
> time_properties: property_get ? ? ? ? ? ? ? ? ? plain: ? 0.97 ? ? psyco:
> 0.74 ? ? ratio: ?1.31
> time_properties: property_set ? ? ? ? ? ? ? ? ? plain: ? 1.02 ? ? psyco:
> 0.92 ? ? ratio: ?1.12
> time_properties: pyproperty_get ? ? ? ? ? ? ? ? plain: ? 1.53 ? ? psyco:
> 1.31 ? ? ratio: ?1.17
> time_properties: pyproperty_set ? ? ? ? ? ? ? ? plain: ? 1.02 ? ? psyco:
> 0.92 ? ? ratio: ?1.11
> time_subdist ? : subdist(i) ? ? ? ? ? ? ? ? ? ? plain: ? 3.65 ? ? psyco:
> 1.64 ? ? ratio: ?2.23
> time_sums ? ? ?: rounding ? ? ? ? ? ? ? ? ? ? ? plain: ? 0.81 ? ? psyco:
> 0.79 ? ? ratio: ?1.03
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 22:57:44 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 02:57:44 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
Message-ID: <pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>

On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:

> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
> 
>> Nobody says you shouldn't check your data. Only that "assert" is not
>> the right way to do that.
> 
> "assert" is not the right way to check your *inputs*. It's a perfectly
> reasonable way to check data which "should" be valid, as well as a way
> to document what variables are supposed to contain.

Where are those variables coming from?

The distinction really boils down to this:

* asserts should never fail. If there is any chance that an assertion 
might fail outside of test suites, then don't use assert.


You can't control what input the caller provides to a function, so unless 
the data is generated inside the function, a caller might provide 
something unexpected. Therefore, assert is inappropriate for checking 
function parameters, even if that function is "private" and only called 
by your own functions.

(1) So-called "private" or "internal" functions have a habit of becoming 
public, and then you have asserts in public functions.

(2) If public() calls _private(x), and _private uses assert to check the 
value of x, there is a risk that if public() is buggy and supplies an 
invalid x, the assertion will never be checked and _private() will return 
incorrect results.

(3) assert is absolutely unsuitable for enforcing pre-conditions and post-
conditions, unless such conditions are mere "guidelines", because assert 
can be switched off at runtime.



It's a fine line to draw. Obviously, if we think something *truly* can 
never fail, we don't bother checking it:

def add(x, y):
    result = x+y
    assert result-y == x
    assert result-x == y
    return result

is probably overkill for most programs, and yet surprisingly those 
assertions will commonly fail for float arguments!




-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 23:07:09 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 03:07:09 GMT
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>

On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:

> def list_items_in_string(list_items, string):
>     for item in list_items:
>         if item in string:
>             return True
>     return False
...
> Any ideas how to make that function look nicer? :)

Change the names. Reverse the order of the arguments. Add a docstring.

Otherwise looks pretty nice to me. Simple, straightforward, and correct.

If you're running Python 2.5 or better, then this is even shorter (and 
probably faster):

def contains(s, targets):
    """Return True if any item of targets is in string s."""
    return any(target in s for target in targets)



-- 
Steven


From tjreedy at udel.edu  Thu Jul  9 23:07:34 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 09 Jul 2009 23:07:34 -0400
Subject: tough-to-explain Python
In-Reply-To: <00720d76$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <h36b9m$7rs$1@ger.gmane.org>

Steven D'Aprano wrote:

> And speaking of binary search:
> 
> [quote]
> I was shocked to learn that the binary search program that Bentley PROVED 
> CORRECT and SUBSEQUENTLY TESTED [emphasis added] in Chapter 5 of 
> "Programming Pearls" contains a bug. Once I tell you what the it is, you 
> will understand why it escaped detection for two decades.
> [end quote]
> 
> http://northernplanets.blogspot.com/2006/07/nearly-all-binary-searches-are-broken.html
> 
> or http://tinyurl.com/nco6yv

The actual report is at
http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-it-nearly.html

The is the so called bug:
"In Programming Pearls Bentley says that the analogous line "sets m to 
the average of l and u, truncated down to the nearest integer." On the 
face of it, this assertion might appear correct, but it fails for large 
values of the int variables low and high. Specifically, it fails if the 
sum of low and high is greater than the maximum positive int value (231 
- 1). The sum overflows to a negative value, and the value stays 
negative when divided by two. In C this causes an array index out of 
bounds with unpredictable results. In Java, it throws 
ArrayIndexOutOfBoundsException."

The is *not* a bug is Bentley program. It is a bug in bad, buggy, insane 
integer arithmetic implementations. low + high should either return the 
right answer, as it will in Python, or raise an overflow error.

tjr



From sjmachin at lexicon.net  Thu Jul  9 23:07:58 2009
From: sjmachin at lexicon.net (John Machin)
Date: Thu, 9 Jul 2009 20:07:58 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<pan.2009.07.10.02.53.57.172000@nowhere.com>
Message-ID: <347b30b2-48a9-49cd-8e33-172325d34a34@v15g2000prn.googlegroups.com>

On Jul 10, 12:53?pm, Nobody <nob... at nowhere.com> wrote:
> On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:
> > For one of my projects, I came across the need to check if one of many
> > items from a list of strings could be found in a long string.
>
> If you need to match many strings or very long strings against the same
> list of items, the following should (theoretically) be optimal:
>
> ? ? ? ? r = re.compile('|'.join(map(re.escape,list_items)))
> ? ? ? ? ...
> ? ? ? ? result = r.search(string)

"theoretically optimal" happens only if the search mechanism builds a
DFA or similar out of the list of strings. AFAIK Python's re module
doesn't.

Try this:
http://hkn.eecs.berkeley.edu/~dyoo/python/ahocorasick/


From miki.tebeka at gmail.com  Thu Jul  9 23:14:30 2009
From: miki.tebeka at gmail.com (lazy1)
Date: Thu, 9 Jul 2009 20:14:30 -0700 (PDT)
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <128ab32f-3609-44a5-9fb3-1a7cb64f04e9@y10g2000prg.googlegroups.com>

Hello Daniel,

> Can someone recommend me a faster plotting library?
I found out gnuplot to be blazing fast for many many points.
I usually just call it using subprocess but there are Python bindings
to it somewhere as well.

HTH,
--
Miki <miki.tebeka at gmail.com>
http://pythonwise.blogspot.com




From http  Thu Jul  9 23:24:54 2009
From: http (Paul Rubin)
Date: 09 Jul 2009 20:24:54 -0700
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
Message-ID: <7x63e1kynt.fsf@ruckus.brouhaha.com>

inkhorn <matt.dubins at sympatico.ca> writes:
> def list_items_in_string(list_items, string):
>     for item in list_items:
>         if item in string:
>             return True
>     return False

You could write that as (untested):

  def list_items_in_string(list_items, string):
     return any(item in string for item in list_items)

but there are faster algorithms you could use if the list is large and
you want to do the test on lots of long strings, etc.


From scriber77 at yahoo.com  Thu Jul  9 23:25:13 2009
From: scriber77 at yahoo.com (scriber77 at yahoo.com)
Date: Thu, 9 Jul 2009 20:25:13 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
Message-ID: <defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>

On Jul 9, 7:54?pm, David Bernier <david... at videotron.ca> wrote:
> Musatov wrote:
> > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > its adopted use in Pakistan. ?The search engine has grown in
> > popularity 10,000 fold following its Beta test launch three months ago
> > in April, 2009. Supporters of the site claim it is better than rival
> > Google upon which platform it is based. Controversy arose after
> > MeAmI.org search code allowed users to search other users Google
> > results with no advertising. "It is truly an innovative thing we are
> > doing," said Founder and CEO, Martin Musatov. "Letting users search
> > the results of other Google users immediately results in a level of
> > accuracy and relevance above and beyond Google." Google changed their
> > API following the launch or MeAmI.org and explored the possibility of
> > blocking site access from MeAmI.org to Google search results but was
> > unable to do so. Critics of MeAmI.org say what it is doing is
> > tantamount to intellectual theft. When asked about this topper Musatov
> > exclaimed, "The Internet was made for people, not companies." An
> > analyst at Goldman Sachs says, requesting to remain anonymous,
> > "MeAmI.org has a strong presence in promoting itself as a vehicle for
> > global activism and to tell you the truth, this makes it much more
> > likely an acquisition target than potential intellectual property
> > violator." Google could not be reached for comment.
>
> Mr. Musatov, ?do you know who originally wrote the
> article above?
>
> Thank you.
>
> David Bernier- Hide quoted text -
>
> - Show quoted text -

Hello, I am an anonymous Professor of Mathematics at a University in
the Midwest. You see, I have been contacted by this "Musatov" fellow
as well and posted a link he sent me to gather a second opinion. I was
immediately attacked by a Mr. Tim Chow from M.I.T. as though I was
him. I explained to him Mr. Musatov had contacted me, that I had read
his simple and very light 3 page paper and said I thought the work in
the equations was elegant and the mending of the binary with the
traditional mathematics symbols inventive. Listen, I understand this
"Musatov" character has annoyed a lot of you and apparently rightfully
so, at least to some extent, has gained a bit of contempt from the
community. But perhaps he is trying to see things a bit differently
and is just not getting the feedback he needs, so he is throwing
tantrums apparently across USENET.

Like I said before, I am just trying to do right by this person who
contacted me, and seemed to be a decent person with a genuine interest
in mathematics. He was very respectful.

Alas, I am at a loss on what specific feedback to give him on his
paper as though I am a professor of Mathematics, Computer Science is
not my specialty.

I told him I would try to get him some feedback on the equations on
page 3.  Would any of you be so kind to help me?

Here is the paper: http://MeAmI.org/pversusnp.pdf

I do thank you for your time.

Good day,

Professor X


From msjmb at tpg.com.au  Thu Jul  9 23:28:15 2009
From: msjmb at tpg.com.au (MichaelW)
Date: Thu, 9 Jul 2009 20:28:15 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
Message-ID: <109bd130-12d6-458b-879b-fa26afab678d@l5g2000pra.googlegroups.com>

On Jul 10, 1:25?pm, scribe... at yahoo.com wrote:
> On Jul 9, 7:54?pm, David Bernier <david... at videotron.ca> wrote:
>
>
>
>
>
> > Musatov wrote:
> > > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > > its adopted use in Pakistan. ?The search engine has grown in
> > > popularity 10,000 fold following its Beta test launch three months ago
> > > in April, 2009. Supporters of the site claim it is better than rival
> > > Google upon which platform it is based. Controversy arose after
> > > MeAmI.org search code allowed users to search other users Google
> > > results with no advertising. "It is truly an innovative thing we are
> > > doing," said Founder and CEO, Martin Musatov. "Letting users search
> > > the results of other Google users immediately results in a level of
> > > accuracy and relevance above and beyond Google." Google changed their
> > > API following the launch or MeAmI.org and explored the possibility of
> > > blocking site access from MeAmI.org to Google search results but was
> > > unable to do so. Critics of MeAmI.org say what it is doing is
> > > tantamount to intellectual theft. When asked about this topper Musatov
> > > exclaimed, "The Internet was made for people, not companies." An
> > > analyst at Goldman Sachs says, requesting to remain anonymous,
> > > "MeAmI.org has a strong presence in promoting itself as a vehicle for
> > > global activism and to tell you the truth, this makes it much more
> > > likely an acquisition target than potential intellectual property
> > > violator." Google could not be reached for comment.
>
> > Mr. Musatov, ?do you know who originally wrote the
> > article above?
>
> > Thank you.
>
> > David Bernier- Hide quoted text -
>
> > - Show quoted text -
>
> Hello, I am an anonymous Professor of Mathematics at a University in
> the Midwest. You see, I have been contacted by this "Musatov" fellow
> as well and posted a link he sent me to gather a second opinion. I was
> immediately attacked by a Mr. Tim Chow from M.I.T. as though I was
> him. I explained to him Mr. Musatov had contacted me, that I had read
> his simple and very light 3 page paper and said I thought the work in
> the equations was elegant and the mending of the binary with the
> traditional mathematics symbols inventive. Listen, I understand this
> "Musatov" character has annoyed a lot of you and apparently rightfully
> so, at least to some extent, has gained a bit of contempt from the
> community. But perhaps he is trying to see things a bit differently
> and is just not getting the feedback he needs, so he is throwing
> tantrums apparently across USENET.
>
> Like I said before, I am just trying to do right by this person who
> contacted me, and seemed to be a decent person with a genuine interest
> in mathematics. He was very respectful.
>
> Alas, I am at a loss on what specific feedback to give him on his
> paper as though I am a professor of Mathematics, Computer Science is
> not my specialty.
>
> I told him I would try to get him some feedback on the equations on
> page 3. ?Would any of you be so kind to help me?
>
> Here is the paper:http://MeAmI.org/pversusnp.pdf
>
> I do thank you for your time.
>
> Good day,
>
> Professor X- Hide quoted text -
>
> - Show quoted text -

Please see reply in the "Breathtaking..." thread. It will come as no
surprise to anyone that "Professor X" and "The Masked Logician" share
the same computer.

MichaelW.


From bcb at undisclosedlocation.net  Thu Jul  9 23:28:46 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Thu, 9 Jul 2009 22:28:46 -0500
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
Message-ID: <Kxy5m.119$Ly1.70@newsfe06.iad>


"Jason S. Friedman" <jason at powerpull.net> wrote in message 
news:mailman.2927.1247192026.8015.python-list at python.org...
> Hello, I administer the Informatica ETL tool at my company.  Part of that 
> role involves creating and enforcing standards.  I want the Informatica 
> developers to add comments to certain key objects and I want to be able to 
> verify (in an automated fashion) that they have done so.
>
> I cannot merely check for non-emptiness; that is trivial to circumvent. On 
> the other hand, I probably do not need to be able to catch developers who 
> are determined to not create comments.  There are not too many of them and 
> perhaps they will find it is easier to write a (useful) comment than to 
> game the system.
>
> Any thoughts on how I might proceed?  Stated plainly, how can I tell when 
> a string more-or-less forms at least one phrase?

Well, you *could* try analyzing the comment text using NLTK: 
http://www.nltk.org/





From bcb at undisclosedlocation.net  Thu Jul  9 23:33:25 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Thu, 9 Jul 2009 22:33:25 -0500
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
Message-ID: <5Cy5m.121$Ly1.67@newsfe06.iad>


<scriber77 at yahoo.com> wrote in message 
news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...

<ka-snip>

Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this! 




From steven at REMOVE.THIS.cybersource.com.au  Thu Jul  9 23:41:43 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 03:41:43 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2931.1247195266.8015.python-list@python.org>
Message-ID: <pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>

On Thu, 09 Jul 2009 23:07:34 -0400, Terry Reedy wrote:

> Steven D'Aprano wrote:
> 
>> And speaking of binary search:
>> 
>> [quote]
>> I was shocked to learn that the binary search program that Bentley
>> PROVED CORRECT and SUBSEQUENTLY TESTED [emphasis added] in Chapter 5 of
>> "Programming Pearls" contains a bug. Once I tell you what the it is,
>> you will understand why it escaped detection for two decades. [end
>> quote]
>> 
>> http://northernplanets.blogspot.com/2006/07/nearly-all-binary-searches-
are-broken.html
>> 
>> or http://tinyurl.com/nco6yv
> 
> The actual report is at
> http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-
it-nearly.html
> 
> The is the so called bug:
> "In Programming Pearls Bentley says that the analogous line "sets m to
> the average of l and u, truncated down to the nearest integer." On the
> face of it, this assertion might appear correct, but it fails for large
> values of the int variables low and high. Specifically, it fails if the
> sum of low and high is greater than the maximum positive int value (231
> - 1). The sum overflows to a negative value, and the value stays
> negative when divided by two. In C this causes an array index out of
> bounds with unpredictable results. In Java, it throws
> ArrayIndexOutOfBoundsException."
> 
> The is *not* a bug is Bentley program.

Wow. That's an impressive set of typos :)


> It is a bug in bad, buggy, insane
> integer arithmetic implementations. low + high should either return the
> right answer, as it will in Python, or raise an overflow error.

Is binary search *supposed* to raise an overflow error if given more than 
2**30 elements? If not, then you're solving a different problem: it's 
just like binary search, but it only works up to a maximum number of 
elements. Now perhaps that's a legitimate problem to solve, but unless 
you make the change in behaviour clear up front, your code has failed to 
live up to specifications and therefore is buggy.

Is there something special about OverflowError that is "better" than 
ArrayIndexOutOfBoundsException?

I don't have "Programming Pearls", and unfortunately the section on 
binary search is not online:

http://netlib.bell-labs.com/cm/cs/pearls/sketch04.html

but there's no reason to imagine that the book will assume -- or even 
state as a requirement for binary search -- that addition will never 
overflow. Far from it: it seems to me that the author is very aware of 
real world constraints, and in the early 1980s, BigInt types were not 
something you took as a given.

Of course *binary search* as an algorithm is not broken. The bug was that 
"Programming Pearls" neglected to take into account overflow when you 
have more than 2**30 items. One way to take that into account is to 
insist on using a language like Python where addition can never overflow. 
But that's not the code presented in "Programming Pearls".


-- 
Steven


From marty.musatov at gmail.com  Thu Jul  9 23:43:08 2009
From: marty.musatov at gmail.com (Musatov)
Date: Thu, 9 Jul 2009 20:43:08 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
Message-ID: <c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>

On Jul 9, 7:54?pm, David Bernier <david... at videotron.ca> wrote:
> Musatov wrote:
> > Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> > its adopted use in Pakistan. ?The search engine has grown in
> > popularity 10,000 fold following its Beta test launch three months ago
> > in April, 2009. Supporters of the site claim it is better than rival
> > Google upon which platform it is based. Controversy arose after
> > MeAmI.org search code allowed users to search other users Google
> > results with no advertising. "It is truly an innovative thing we are
> > doing," said Founder and CEO, Martin Musatov. "Letting users search
> > the results of other Google users immediately results in a level of
> > accuracy and relevance above and beyond Google." Google changed their
> > API following the launch or MeAmI.org and explored the possibility of
> > blocking site access from MeAmI.org to Google search results but was
> > unable to do so. Critics of MeAmI.org say what it is doing is
> > tantamount to intellectual theft. When asked about this topper Musatov
> > exclaimed, "The Internet was made for people, not companies." An
> > analyst at Goldman Sachs says, requesting to remain anonymous,
> > "MeAmI.org has a strong presence in promoting itself as a vehicle for
> > global activism and to tell you the truth, this makes it much more
> > likely an acquisition target than potential intellectual property
> > violator." Google could not be reached for comment.
>
> Mr. Musatov, ?do you know who originally wrote the
> article above?
>
> Thank you.
>
> David Bernier- Hide quoted text -
>
> - Show quoted text -

Yes.


From timr at probo.com  Thu Jul  9 23:44:50 2009
From: timr at probo.com (Tim Roberts)
Date: Thu, 09 Jul 2009 20:44:50 -0700
Subject: How to use Python to interface with Web pages?
References: <1d17d40d-ee5a-4f67-a6f0-1d824c54da41@m7g2000prd.googlegroups.com>
Message-ID: <r8ed55pkd47v35li0vdemrkse1jg1leena@4ax.com>

Peter <peter.milliken at gmail.com> wrote:
>
>Any help would be appreciated :-)
>
>I want to write an auction sniping tool in Python.

Please don't.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From timr at probo.com  Thu Jul  9 23:50:30 2009
From: timr at probo.com (Tim Roberts)
Date: Thu, 09 Jul 2009 20:50:30 -0700
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
Message-ID: <vded55tanedt94386elhh851j7felns1md@4ax.com>

TheSeeker <duane.kaufman at gmail.com> wrote:
>
>I am embarking on teaching myself Microsoft UI Automation using Python
>as the scripting language.

The University of North Carolina at Chapel Hill has a great Python package
called pyAA that does exactly this:

http://www.cs.unc.edu/Research/assist/developer.shtml
http://mindtrove.info/articles/gui-automation-with-pyaa/
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From scriptlearner at gmail.com  Fri Jul 10 01:29:15 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Thu, 9 Jul 2009 22:29:15 -0700 (PDT)
Subject: Looking for the right library for a simple HTTP client
Message-ID: <fccd9f2d-8021-4087-9a38-ace47fc40175@r15g2000pra.googlegroups.com>

I am trying to implement a simple client that can do the following:
1)to send the following kinds of HTTP requests and validate responses
1.1 GET
1.2 POST with application/x-www-form-urlencoded encoding
1.3 POST with multipart/form-data encoding

2)to set any number of (even duplicate) headers.  For example, I may
intentionally add the following Cookie: headers to a request:
Cookie: id_1=v1;Domain=sample.com;Path=/
Cookie: id_1=v1;Domain=sample.com;Path=/ <--same as the one above
Cookie: id_2=v1;Domain=sample.com;Path=/

3)to set proxy cfg so requests can go through a proxy server to reach
the target server.

4)to send multiple requests simultaneously.


I have Python 2.4.1 on Solaris 9 and 10, and I don't have any plan to
upgrade to latest version of Python.

I looked around and I found httplib and urllib.  Are they sufficient
for my tasks 1 to 3 above?  Any good sample codes will be great.
Thanks.


From david250 at videotron.ca  Fri Jul 10 01:45:36 2009
From: david250 at videotron.ca (David Bernier)
Date: Fri, 10 Jul 2009 01:45:36 -0400
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
Message-ID: <h36ki102d7m@news5.newsguy.com>

Musatov wrote:
> On Jul 9, 7:54 pm, David Bernier <david... at videotron.ca> wrote:
>> Musatov wrote:
>>> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
>>> its adopted use in Pakistan.  The search engine has grown in
>>> popularity 10,000 fold following its Beta test launch three months ago
>>> in April, 2009. Supporters of the site claim it is better than rival
>>> Google upon which platform it is based. Controversy arose after
>>> MeAmI.org search code allowed users to search other users Google
>>> results with no advertising. "It is truly an innovative thing we are
>>> doing," said Founder and CEO, Martin Musatov. "Letting users search
>>> the results of other Google users immediately results in a level of
>>> accuracy and relevance above and beyond Google." Google changed their
>>> API following the launch or MeAmI.org and explored the possibility of
>>> blocking site access from MeAmI.org to Google search results but was
>>> unable to do so. Critics of MeAmI.org say what it is doing is
>>> tantamount to intellectual theft. When asked about this topper Musatov
>>> exclaimed, "The Internet was made for people, not companies." An
>>> analyst at Goldman Sachs says, requesting to remain anonymous,
>>> "MeAmI.org has a strong presence in promoting itself as a vehicle for
>>> global activism and to tell you the truth, this makes it much more
>>> likely an acquisition target than potential intellectual property
>>> violator." Google could not be reached for comment.
>> Mr. Musatov,  do you know who originally wrote the
>> article above?
>>
>> Thank you.
>>
>> David Bernier- Hide quoted text -
>>
>> - Show quoted text -
> 
> Yes.

Mr. Musatov, do you know the name of the person who
originally wrote the article above?

Thank you.

David Bernier


From scriber77 at yahoo.com  Fri Jul 10 01:52:14 2009
From: scriber77 at yahoo.com (Floetry)
Date: Thu, 9 Jul 2009 22:52:14 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<5Cy5m.121$Ly1.67@newsfe06.iad>
Message-ID: <803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3@2g2000prl.googlegroups.com>

On Jul 9, 8:33?pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> <scribe... at yahoo.com> wrote in message
>
> news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...
>
> <ka-snip>
>
> Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this!

Any reason "ka"-snip?

Binomial Theorem: page 3. http://MeAmI.org/pversusnp.pdf



From s.deshe at gmail.com  Fri Jul 10 02:18:03 2009
From: s.deshe at gmail.com (slamdunk)
Date: Thu, 9 Jul 2009 23:18:03 -0700 (PDT)
Subject: way for a function to understand whether it's being run through a 
	OnCreate callback or not
Message-ID: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>

is there a way for a function to understand whether it's being run
through a OnCreate callback or not?
I have working functions that I want to recycle through the OnCreate
but need to catch the "nuke.thisNode()" bit inside them so they can
still function when called manually through other scripts functions.


From bcb at undisclosedlocation.net  Fri Jul 10 02:21:46 2009
From: bcb at undisclosedlocation.net (Bruce C. Baker)
Date: Fri, 10 Jul 2009 01:21:46 -0500
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<5Cy5m.121$Ly1.67@newsfe06.iad>
	<803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3@2g2000prl.googlegroups.com>
Message-ID: <X3B5m.1452$yk5.1278@newsfe02.iad>


"Floetry" <scriber77 at yahoo.com> wrote in message 
news:803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3 at 2g2000prl.googlegroups.com...
On Jul 9, 8:33 pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> <scribe... at yahoo.com> wrote in message
>
> news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...
>
> <ka-snip>
>
> Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this!

Any reason "ka"-snip?

Binomial Theorem: page 3. http://MeAmI.org/pversusnp.pdf

_________________________________________________

Well, *Martin*, since you think I'm dead, it could only have been my "ka" 
that did the snipping. Surely a polymath of your vast accomplishments will 
have no problem with the religio-historical reference, eh, *Martin*? (I'm 
predicting that not only will you *not* recognize it, you'll find it beneath 
your notice. No fair googling, *Martin*!)






From clp2 at rebertia.com  Fri Jul 10 02:23:17 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 9 Jul 2009 23:23:17 -0700
Subject: way for a function to understand whether it's being run through a
	OnCreate callback or not
In-Reply-To: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
References: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
Message-ID: <50697b2c0907092323n6da421f1o9b3faec654bd88e7@mail.gmail.com>

On Thu, Jul 9, 2009 at 11:18 PM, slamdunk<s.deshe at gmail.com> wrote:
> is there a way for a function to understand whether it's being run
> through a OnCreate callback or not?
> I have working functions that I want to recycle through the OnCreate
> but need to catch the "nuke.thisNode()" bit inside them so they can
> still function when called manually through other scripts functions.

Your question lacks context. What's an OnCreate callback?

Cheers,
Chris
-- 
http://blog.rebertia.com


From gherron at islandtraining.com  Fri Jul 10 02:59:22 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Thu, 09 Jul 2009 23:59:22 -0700
Subject: way for a function to understand whether it's being run through
	a 	OnCreate callback or not
In-Reply-To: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
References: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
Message-ID: <4A56E6CA.5090802@islandtraining.com>

slamdunk wrote:
> is there a way for a function to understand whether it's being run
> through a OnCreate callback or not?
> I have working functions that I want to recycle through the OnCreate
> but need to catch the "nuke.thisNode()" bit inside them so they can
> still function when called manually through other scripts functions.
>   
You've given us almost *NO* clue what you are talking about.   I suppose 
I could Google "onCreate", and perhaps "nuke" and "thisNode", and see 
what falls out.  But why would I?  If you want our help, *you* take the 
time to tell is what you are asking about. 

You may want to start here:  
http://www.catb.org/~esr/faqs/smart-questions.html#intro

Gary Herron



From kf9150 at gmail.com  Fri Jul 10 03:13:54 2009
From: kf9150 at gmail.com (Kelie)
Date: Fri, 10 Jul 2009 00:13:54 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<vded55tanedt94386elhh851j7felns1md@4ax.com>
Message-ID: <fc148aba-ee96-4306-9ee4-ef1d8efeb8d0@i6g2000yqj.googlegroups.com>

On Jul 9, 5:50?pm, Tim Roberts <t... at probo.com> wrote:
> The University of North Carolina at Chapel Hill has a great Python package
> called pyAA that does exactly this:
>
> http://www.cs.unc.edu/Research/assist/developer.shtmlhttp://mindtrove.info/articles/gui-automation-with-pyaa/
> --
> Tim Roberts, t... at probo.com

Thanks Tim. From this page http://sourceforge.net/projects/uncassist/files/,
there isn't a installer for Python2.5 or higher. Didn't find the
source code there either.



From marty.musatov at gmail.com  Fri Jul 10 03:19:40 2009
From: marty.musatov at gmail.com (Musatov)
Date: Fri, 10 Jul 2009 00:19:40 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<5Cy5m.121$Ly1.67@newsfe06.iad>
	<803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3@2g2000prl.googlegroups.com>
	<X3B5m.1452$yk5.1278@newsfe02.iad>
Message-ID: <1d58ce00-9436-4220-a7ad-fc586df6625c@h18g2000yqj.googlegroups.com>

On Jul 9, 11:21?pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
wrote:
> "Floetry" <scribe... at yahoo.com> wrote in message
>
> news:803a7f06-8e43-4ff5-86a6-9fd9d2eee0c3 at 2g2000prl.googlegroups.com...
> On Jul 9, 8:33 pm, "Bruce C. Baker" <b... at undisclosedlocation.net>
> wrote:
>
> > <scribe... at yahoo.com> wrote in message
>
> >news:defacf35-6149-485a-8f03-15472d63de43 at a39g2000pre.googlegroups.com...
>
> > <ka-snip>
>
> > Oh, puh-LEEZ, Martin! A two-year-old wouldn't be fooled by this!
>
> Any reason "ka"-snip?
>
> Binomial Theorem: page 3.http://MeAmI.org/pversusnp.pdf
>
> _________________________________________________
>
> Well, *Martin*, since you think I'm dead, it could only have been my "ka"
> that did the snipping. Surely a polymath of your vast accomplishments will
> have no problem with the religio-historical reference, eh, *Martin*? (I'm
> predicting that not only will you *not* recognize it, you'll find it beneath
> your notice. No fair googling, *Martin*!)

I did not Google.

ka in ancient Egypt, the supposed spiritual part of an individual
human being or god, which survived (with the soul) after death and
could reside in a statue of the person.

ELIZABETH KNOWLES. "ka." The Oxford Dictionary of Phrase and Fable.
Oxford University Press. 2006. Encyclopedia.com. 10 Jul. 2009 <http://
www.encyclopedia.com>.

In a third class of religion?usually heavily interlaced with fetishism?
magic, momentary and special deities, nature gods, and deities
personifying natural functions (such as the Egyptian solar god Ra, the
Babylonian goddess of fertility Ishtar, the Greek sea-god Poseidon,
and the Hindu goddess of death and destruction *Ka*li) emerge and are
incorporated into a system of mythology and ritual. Sometimes they
take on distinctively human characteristics (see anthropomorphism).

The axis of reason - equinox, mass, and time - the orbits of ...Et a
basso profundo hashi-hashi-brek-a-time todo ka tiempo. > Vozacka
dozvola macarana lambada ... (&?&@?&?&?@&?&)) P. -- Musatov http://MeAmI.org
...


From martin at librador.com  Fri Jul 10 03:30:48 2009
From: martin at librador.com (Martin Vilcans)
Date: Fri, 10 Jul 2009 09:30:48 +0200
Subject: way for a function to understand whether it's being run through a
	OnCreate callback or not
In-Reply-To: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
References: <04fb0113-bea2-427f-9a6a-cb742184dd02@g1g2000pra.googlegroups.com>
Message-ID: <f782707a0907100030w7e86fd8dg5585c210f6cc50c@mail.gmail.com>

On Fri, Jul 10, 2009 at 8:18 AM, slamdunk<s.deshe at gmail.com> wrote:
> is there a way for a function to understand whether it's being run
> through a OnCreate callback or not?
> I have working functions that I want to recycle through the OnCreate
> but need to catch the "nuke.thisNode()" bit inside them so they can
> still function when called manually through other scripts functions.

I suppose you're programming for The Foundry's Nuke. Python is used in
lots of different contexts, and most people on this list use Python
for something totally unrelated to video.

As an attempt at answering your question, you can add a parameter to
your function that tells from where it's called. I.e. you put True in
the parameter when it is called from OnCreate, False when it is not.
But that isn't a very good design. A function should not need to care
from where it is called. You probably want to have the node as a
parameter to the function instead of calling nuke.thisNode inside of
it.

I can't find documentation for the OnCreate function online. Do you
mean that you can only call nuke.thisNode() from inside OnCreate?

Here's my guess of what I think you want to do:

def OnCreate():
    # call your function with the current node as argument
    your_function(nuke.thisNode())

def your_function(node):
    # The function takes a node as an argument.
    # Do whatever you want here

For more Nuke-specific questions, you'd probably get better results by
asking on the Nuke-python mailing list:

http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-python


-- 
martin at librador.com
http://www.librador.com


From dstanek at dstanek.com  Fri Jul 10 03:34:05 2009
From: dstanek at dstanek.com (David Stanek)
Date: Fri, 10 Jul 2009 03:34:05 -0400
Subject: Looking for the right library for a simple HTTP client
In-Reply-To: <fccd9f2d-8021-4087-9a38-ace47fc40175@r15g2000pra.googlegroups.com>
References: <fccd9f2d-8021-4087-9a38-ace47fc40175@r15g2000pra.googlegroups.com>
Message-ID: <de32cc030907100034j32a3f4c3y127bb3f94a41bb74@mail.gmail.com>

On Fri, Jul 10, 2009 at 1:29 AM,
scriptlearner at gmail.com<scriptlearner at gmail.com> wrote:
> I am trying to implement a simple client that can do the following:
> 1)to send the following kinds of HTTP requests and validate responses
> 1.1 GET
> 1.2 POST with application/x-www-form-urlencoded encoding
> 1.3 POST with multipart/form-data encoding
>
> 2)to set any number of (even duplicate) headers. ?For example, I may
> intentionally add the following Cookie: headers to a request:
> Cookie: id_1=v1;Domain=sample.com;Path=/
> Cookie: id_1=v1;Domain=sample.com;Path=/ <--same as the one above
> Cookie: id_2=v1;Domain=sample.com;Path=/
>
> 3)to set proxy cfg so requests can go through a proxy server to reach
> the target server.
>
> 4)to send multiple requests simultaneously.
>
>
> I have Python 2.4.1 on Solaris 9 and 10, and I don't have any plan to
> upgrade to latest version of Python.
>
> I looked around and I found httplib and urllib. ?Are they sufficient
> for my tasks 1 to 3 above? ?Any good sample codes will be great.
> Thanks.
> --
> http://mail.python.org/mailman/listinfo/python-list
>

I like urllib2. The examples[1] are pretty good.

[1] http://www.python.org/doc/2.4.1/lib/urllib2-examples.html

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From bhardwajjayesh at gmail.com  Fri Jul 10 03:54:52 2009
From: bhardwajjayesh at gmail.com (jayesh bhardwaj)
Date: Fri, 10 Jul 2009 00:54:52 -0700 (PDT)
Subject: Httplib issues
Message-ID: <017b8d15-6a4c-4a6c-8d92-1f8e8cbf4c6d@t33g2000yqe.googlegroups.com>

Hi,
i was trying to download file frm a terminal having apache with
httplib manipulation. It worked, now i want to upload file to the
terminal. Can this b done by httplib too?


From lie.1296 at gmail.com  Fri Jul 10 04:03:05 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 10 Jul 2009 08:03:05 GMT
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <mailman.2910.1247165872.8015.python-list@python.org>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>	<h34t9k$kp8$1@south.jnrs.ja.net>	<da7092380907090906ua73ff03y78df9623cf515862@mail.gmail.com>	<op.uws939iha8ncjz@gnudebst>
	<mailman.2910.1247165872.8015.python-list@python.org>
Message-ID: <ZAC5m.3933$ze1.529@news-server.bigpond.net.au>

Fri?rik M?r J?nsson wrote:
> Hi Rhodri,
> 
>> It's only really a pitfall if you try to use the built-in after you've
>> redefined it.  That's the thing to keep an eye open for.
> 
> You're right, but in cases where you're editing a codebase which you
> didn't author entirely by yourself you may not be aware of that.
> 
> That said, if the codebase you're working on is structured (short,
> concise methods) you should be working with small, consumable scopes you
> can inhale in entirety before modifying.
> 
> Regards,
> Fri?rik M?r

But if you are responsible for a large codebase that you don't write
yourself, it is doubtful that you're a real newbie.


From lie.1296 at gmail.com  Fri Jul 10 04:47:51 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Fri, 10 Jul 2009 08:47:51 GMT
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <mailman.2924.1247184109.8015.python-list@python.org>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<mailman.2924.1247184109.8015.python-list@python.org>
Message-ID: <XeD5m.3944$ze1.1969@news-server.bigpond.net.au>

Simon Forman wrote:
> On Thu, Jul 9, 2009 at 9:42 AM, Nick<nleioatt at gmail.com> wrote:
> <snip>
>>    fields = line.split()
>>    for i in range(len(fields)):
>>        fields[i] = float(fields[i])
> 
> 
> instead of the above code you could say:
> 
> fields = [float(n) for n in in line.split()]
> 
> Have fun getting back into python! :]  (A lot has changed in the last few years)

>>> fields = [float(n) for n in in line.split()]
  File "<stdin>", line 1
    fields = [float(n) for n in in line.split()]
                                 ^
SyntaxError: invalid syntax

s/in in/in/


From jeremy+complangpython at jeremysanders.net  Fri Jul 10 04:51:29 2009
From: jeremy+complangpython at jeremysanders.net (Jeremy Sanders)
Date: Fri, 10 Jul 2009 09:51:29 +0100
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <h36veh$g4h$1@gemini.csx.cam.ac.uk>

tt-industries wrote:

> Hi,
> 
> I am programming a oscilloscope module in Python. For this reason, I
> want to plot very many data points as fast as possible. This can be
> more than 100 000 at once. So far I have been using the ploting module
> of wxPython. However, it becomes unstable for more than 25000 points.
> Can someone recommend me a faster plotting library? It would be really
> cool if one could embed this in wxPython. If someone has an idea I
> would be very glad about answer.

Veusz can plot a line with that many points with that many points in a 
couple of seconds on my system. It's a bit faster without antialiasing, 
slower if you want to actually plot markers at each position.

Jeremy

-- 
Jeremy Sanders
http://www.jeremysanders.net/



From deets at nospam.web.de  Fri Jul 10 04:59:08 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 10 Jul 2009 10:59:08 +0200
Subject: Httplib issues
In-Reply-To: <017b8d15-6a4c-4a6c-8d92-1f8e8cbf4c6d@t33g2000yqe.googlegroups.com>
References: <017b8d15-6a4c-4a6c-8d92-1f8e8cbf4c6d@t33g2000yqe.googlegroups.com>
Message-ID: <7boe6sF249o1gU1@mid.uni-berlin.de>

jayesh bhardwaj schrieb:
> Hi,
> i was trying to download file frm a terminal having apache with
> httplib manipulation. It worked, now i want to upload file to the
> terminal. Can this b done by httplib too?

"Upload file to the terminal" makes no sense to me. You can upload 
something to a server. You can run a terminal. You can run a ssh-session 
to a server in a terminal. You can't upload to a terminal.

But you can use httplib (or better urllib2) to make http-post-requests 
to webservers.

And last but not least the ubiquious

http://catb.org/esr/faqs/smart-questions.html

Diez


From jeanmichel at sequans.com  Fri Jul 10 05:11:33 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 10 Jul 2009 11:11:33 +0200
Subject: Clarity vs. code reuse/generality
In-Reply-To: <pan.2009.07.10.02.28.04.344000@nowhere.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
Message-ID: <4A5705C5.6010301@sequans.com>

Nobody wrote:
> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>
>   
>> Nobody says you shouldn't check your data. Only that "assert" is not the  
>> right way to do that.
>>     
>
> "assert" is not the right way to check your *inputs*. It's a perfectly
> reasonable way to check data which "should" be valid, as well as a way to
> document what variables are supposed to contain.
>
>   
Maybe, one of the assert problem is a semantic issue. Assert is a 
convenient way to write in the code "This is a requirement, get lost if 
you don't fit in". However it seems we often forget that builtin asserts 
can be disabled.
One possible solution for those who prefer to write assertions instead a 
'if A then Exception' is to write their own assertion statement and 
**raise an exception** that will not be disabled at runtime.

Jea-Michel


From garabik-news-2005-05 at kassiopeia.juls.savba.sk  Fri Jul 10 05:23:54 2009
From: garabik-news-2005-05 at kassiopeia.juls.savba.sk (garabik-news-2005-05 at kassiopeia.juls.savba.sk)
Date: Fri, 10 Jul 2009 09:23:54 +0000 (UTC)
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com>
Message-ID: <h371ba$36l$1@aioe.org>

Tim Harig <usernet at ilthio.net> wrote:
> On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
>> I would like to learn a way of changing the colour of a particular
>> part of the output text. I've tried the following

> On Unix operating systems this would be done through the curses interface:
> 
> http://docs.python.org/library/curses.html

Or using ANSI colour codes:

colours = {
            'none'       :    "",
            'default'    :    "\033[0m",
            'bold'       :    "\033[1m",
            'underline'  :    "\033[4m",
            'blink'      :    "\033[5m",
            'reverse'    :    "\033[7m",
            'concealed'  :    "\033[8m",

            'black'      :    "\033[30m",
            'red'        :    "\033[31m",
            'green'      :    "\033[32m",
            'yellow'     :    "\033[33m",
            'blue'       :    "\033[34m",
            'magenta'    :    "\033[35m",
            'cyan'       :    "\033[36m",
            'white'      :    "\033[37m",

            'on_black'   :    "\033[40m",
            'on_red'     :    "\033[41m",
            'on_green'   :    "\033[42m",
            'on_yellow'  :    "\033[43m",
            'on_blue'    :    "\033[44m",
            'on_magenta' :    "\033[45m",
            'on_cyan'    :    "\033[46m",
            'on_white'   :    "\033[47m",

            'beep'       :    "\007",

            # non-standard attributes, supported by some terminals 
            'dark'         :    "\033[2m",
            'italic'       :    "\033[3m",
            'rapidblink'   :    "\033[6m",
            'strikethrough':    "\033[9m",
            }

print colours['red'], 'this is red', colours['blue'], 'blue', colours['on_green'], 'and with a green background', colours['default']

-- 
 -----------------------------------------------------------
| Radovan Garab?k http://kassiopeia.juls.savba.sk/~garabik/ |
| __..--^^^--..__    garabik @ kassiopeia.juls.savba.sk     |
 -----------------------------------------------------------
Antivirus alert: file .signature infected by signature virus.
Hi! I'm a signature virus! Copy me into your signature file to help me spread!


From roland at catalogix.se  Fri Jul 10 05:33:25 2009
From: roland at catalogix.se (Roland Hedberg)
Date: Fri, 10 Jul 2009 11:33:25 +0200
Subject: A zlib question
Message-ID: <80F42625-5FB2-438F-AFF2-913236A6D336@catalogix.se>

Hi!

I have a problem with zlib and compressing/decompressing according to  
RFC 1951.

It seems like I can decompress, something compressed according to RFC  
1951 by someone else, provided I set wbits to something negative (used  
-8 but I guess any negative number would work?).

But how can I compress using zlib so it doesn't add a gzip header ?

-- Roland 


From jeanmichel at sequans.com  Fri Jul 10 05:39:54 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 10 Jul 2009 11:39:54 +0200
Subject: the ultimate logging facility for debugging code
Message-ID: <4A570C6A.2060904@sequans.com>

Greetings,

Sorry for the dubious title :o). I was wandering if there is a standard 
(or reliable) python module that implements the following feature:

http://code.activestate.com/recipes/198078/
 >>>Recipe 198078: Wrapping method calls (meta-class example)
 >>>
 >>>A metaclass is used to wrap all (or just some) methods for logging 
purposes. The underlying mechanism can be used as well to check pre/post 
conditions, attribute access,... The basic point is, that the actual 
class must not be changed in any way to achive the desired effect.
   

I had to adapt the code to some of my needs, but now it's almost 
working, by simply defining a metaclass for any of my class, I get the 
class methods calls logged with the instance that called the method, the 
method name, the call line in the file, the parameter **value**  passed 
to the method and the returned value.
It just saved me from hours of ipython interactive debugging with the 
old print way, and to beauty of it: I don't have to write any 
"self._log('Please log me')" line.

As it is so useful, I bet there is a module that is doing this in a more 
reliable way that I did. Anyone has heard of it ?

Jean-Michel



From jhinak.sen at gmail.com  Fri Jul 10 05:41:03 2009
From: jhinak.sen at gmail.com (jhinak sen)
Date: Fri, 10 Jul 2009 15:11:03 +0530
Subject: help me to find the error
Message-ID: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>

hi,
i am a beginner in python language,

i am trying with this programme :
to find the addition and mean from a data set in a file and writing the mean
and sum in some other file :
""
*#! /usr/bin/env python

import re
import cPickle as p
import math
from numpy import *

f0= open("temp9","r+").readlines()
f2= open("out1","r+")
add_1=[ ];
for i in range(0, len(f0)):
        f1=f0[i].split()
        add= float(f1[1])+float(f1[2])
    mean= float(add)/2
        print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
repr(mean).ljust(7)
        add_1.append(add)
    add_1.append(mean)
        f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
repr(mean).ljust(7))
print "printing from file"
for i in range(0, len(add_1),2):
        print add_1[i],"        ", add_1[i+1]

f0.close()
f2.close()*


""

and this programme is givving me this error :

""    *Traceback (most recent call last):
  File "./temporary1.py", line 24, in <module>
    f0.close()
AttributeError: 'list' object has no attribute 'close'*
""

please help to to find the error.
or suggest some simpler or better way

note:
1)file "temp9" is already exist
2)this programme is giving me all my outputs, but at the end of the out
..its giving me that error.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/3145e82b/attachment-0001.html>

From contact at xavierho.com  Fri Jul 10 05:53:15 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 10 Jul 2009 17:53:15 +0800
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <2d56febf0907100253m55cca65eo1889431de5b9835d@mail.gmail.com>

I'm new to Python myself, but I think it's because the method readlist()
returns a list. Hence, f0 is typed 'list'. And lists can't be closed.

If you leave it to:

*f0= open("temp9","r+")

*and then assign another variable to the readlist, such as:

*lines = f0.readlines()*

Then in the for loop, change f1 to

*f1=lines[i].split()*

That may just stop it from complaining.

Untested, but logically it's sound.

Hope that works,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Fri, Jul 10, 2009 at 5:41 PM, jhinak sen <jhinak.sen at gmail.com> wrote:

> hi,
> i am a beginner in python language,
>
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the
> mean and sum in some other file :
> ""
> *#! /usr/bin/env python
>
> import re
> import cPickle as p
> import math
> from numpy import *
>
> f0= open("temp9","r+").readlines()
> f2= open("out1","r+")
> add_1=[ ];
> for i in range(0, len(f0)):
>         f1=f0[i].split()
>         add= float(f1[1])+float(f1[2])
>     mean= float(add)/2
>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
> repr(mean).ljust(7)
>         add_1.append(add)
>     add_1.append(mean)
>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
> repr(mean).ljust(7))
> print "printing from file"
> for i in range(0, len(add_1),2):
>         print add_1[i],"        ", add_1[i+1]
>
> f0.close()
> f2.close()*
>
>
> ""
>
> and this programme is givving me this error :
>
> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""
>
> please help to to find the error.
> or suggest some simpler or better way
>
> note:
> 1)file "temp9" is already exist
> 2)this programme is giving me all my outputs, but at the end of the out
> ..its giving me that error.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/70ba34a7/attachment-0001.html>

From gabriel.rossetti at arimaz.com  Fri Jul 10 05:57:23 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 10 Jul 2009 11:57:23 +0200
Subject: Threading.Condition problem
Message-ID: <4A571083.8030403@arimaz.com>

Hello everyone,

I wrote a small example that listens for xmpp msgs in a thread. The main 
program calls a function that blocks (using Condition.wait) until a msg 
has been received and then returns the msg. When a msg arrives, it is 
put in a variable in the thread's object, it then calls the notify() 
attr on the Condition object. For some reason, this doesn't work, the 
thread gets the msg, tries to notify the Condition object, fails because 
the lock has not been acquired yet and blocks. I tried ignoring the 
failure, thinking that since it has not been acquired yet then when it 
is, it will get the msg right away and never call Condition.wait, thus 
not causing any problems, but this does not work either. Does someone 
know what I am doing wrong? I attached the code to this msg.

Thank you,
Gabriel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: xmpp_client.py
Type: text/x-python
Size: 6127 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/1645640b/attachment-0001.py>

From bearophileHUGS at lycos.com  Fri Jul 10 05:58:33 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 10 Jul 2009 02:58:33 -0700 (PDT)
Subject: psyco V2 beta2 benchmark
References: <h2nhhs$g5m$00$1@news.t-online.com>
Message-ID: <c795efdd-4a73-46f8-8a63-5e1d6c86e4c3@32g2000yqj.googlegroups.com>

larudwer, is that time_subdist subdist(i) a bad worsening? Something
to be fixed in Psyco2?

Bye,
bearophile


From sebastian.schabe at gmx.de  Fri Jul 10 06:01:51 2009
From: sebastian.schabe at gmx.de (Sebastian Schabe)
Date: Fri, 10 Jul 2009 12:01:51 +0200
Subject: Concatenating images (numpy arrays), but they look like HSV images
In-Reply-To: <mailman.2909.1247162905.8015.python-list@python.org>
References: <4a5629ba$1@news.fhg.de>
	<mailman.2909.1247162905.8015.python-list@python.org>
Message-ID: <4a5710ea$1@news.fhg.de>

Robert Kern schrieb:
> Probably, you need to use zeros(..., dtype=uint8). When you use 
> dtype=int, that will result in dtype=int arrays. I suspect that 
> matplotlib is then interpreting that to mean that you want it to treat 
> the input as scalar data (which it will pass through a colormap) rather 
> than an RGB image.
> 

Thanks Robert, that was exactly the problem. Now I'am really wondering 
how one can know such details. Well, with your answer I searched again 
in the mathplotlib documentation and under the function imshow(X, ...) I 
indeed found the hint, that X has to be an uint8 or float array or PIL 
image, but before I hadn't known where to search.

So again, thank you

Sebastian


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 10 06:14:26 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 10 Jul 2009 12:14:26 +0200
Subject: property using a classmethod
In-Reply-To: <rTp5m.3784$ze1.643@news-server.bigpond.net.au>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<ewl5m.3746$ze1.3371@news-server.bigpond.net.au>
	<4a55e8e0$0$8041$426a34cc@news.free.fr>
	<rTp5m.3784$ze1.643@news-server.bigpond.net.au>
Message-ID: <4a571483$0$19592$426a74cc@news.free.fr>

Lie Ryan a ?crit :
> Bruno Desthuilliers wrote:
>> Lie Ryan a ?crit :
>>> Emanuele D'Arrigo wrote:
>> (snip)
>>>> Ultimately all I want is a non-callable class-level attribute
>>>> MyClass.myProperty that gives the result of MyClass.myClassMethod().
>>> This works like what you seem to want (it's ugly):
>> Ugly, indeed. And an extreme case of arbitrary overcomplexification too :-/
>>
>> (snip rube goldberg code)
>>
> 
> Can't think of anything simpler than that without meddling with
> descriptor.

Hmmm... Rereading the OP's spec, I guess you understood it better than I 
did - seems the OP wants to be able to call the "property" on the class 
object itself - which won't work with the builtin property type. So my 
own proposed solution won't do :-/

But still, "meddling with descriptor" is *way* simpler than your 
proposed solution. Here's a simple non-binding descriptor that do the job:

class ClsProperty(object):
     def __init__(self, fget):
         if not isinstance(fget, (classmethod, staticmethod)):
             raise ValueError(
               "fget must be a classmethod or staticmethod"
               )
         self.fget = fget

     def __get__(self, obj, cls=None):
         if cls is None:
             assert obj is not None
             cls = type(obj)
         return self.fget.__get__(obj, cls)()


# example use
class Foo(object):
     @classmethod
     def bar(cls):
         return "%s.bar" % cls.__name__

     quux = ClsProperty(bar)


> I'm not even sure descriptor can help here as it seems
> descriptor needs an instance?

wrt/ descriptors, no, they don't "need" an instance, at least for 
non-binding descriptors. Else, MyClass.MyMethod would return the 
MyClass.__dict__['MyMethod'] function, not an unbound method object !-)




From jhinak.sen at gmail.com  Fri Jul 10 06:20:47 2009
From: jhinak.sen at gmail.com (jhinak sen)
Date: Fri, 10 Jul 2009 15:50:47 +0530
Subject: Python-list Digest, Vol 70, Issue 142
In-Reply-To: <mailman.57.1247220004.18838.python-list@python.org>
References: <mailman.57.1247220004.18838.python-list@python.org>
Message-ID: <3d4ff96c0907100320s346403baga8795d0c61cd54d7@mail.gmail.com>

hey Xavier

thnx a lot :)
its working and ya.. i got your pont regarding typecasting .

jhinak

On Fri, Jul 10, 2009 at 3:30 PM, <python-list-request at python.org> wrote:

> Send Python-list mailing list submissions to
>        python-list at python.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
>        http://mail.python.org/mailman/listinfo/python-list
> or, via email, send a message with subject or body 'help' to
>        python-list-request at python.org
>
> You can reach the person managing the list at
>        python-list-owner at python.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Python-list digest..."
>
> Today's Topics:
>
>   1. A zlib question (Roland Hedberg)
>   2. Re: help me to find the error (Xavier Ho)
>   3. Re: Concatenating images (numpy arrays), but they look like
>      HSV images (Sebastian Schabe)
>
>
> ---------- Forwarded message ----------
> From: Roland Hedberg <roland at catalogix.se>
> To: python-list at python.org
> Date: Fri, 10 Jul 2009 11:33:25 +0200
> Subject: A zlib question
> Hi!
>
> I have a problem with zlib and compressing/decompressing according to RFC
> 1951.
>
> It seems like I can decompress, something compressed according to RFC 1951
> by someone else, provided I set wbits to something negative (used -8 but I
> guess any negative number would work?).
>
> But how can I compress using zlib so it doesn't add a gzip header ?
>
> -- Roland
>
>
> ---------- Forwarded message ----------
> From: Xavier Ho <contact at xavierho.com>
> To: python-list at python.org
> Date: Fri, 10 Jul 2009 17:53:15 +0800
> Subject: Re: help me to find the error
> I'm new to Python myself, but I think it's because the method readlist()
> returns a list. Hence, f0 is typed 'list'. And lists can't be closed.
>
> If you leave it to:
>
> *f0= open("temp9","r+")
>
> *and then assign another variable to the readlist, such as:
>
> *lines = f0.readlines()*
>
> Then in the for loop, change f1 to
>
> *f1=lines[i].split()*
>
> That may just stop it from complaining.
>
> Untested, but logically it's sound.
>
> Hope that works,
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
>
> On Fri, Jul 10, 2009 at 5:41 PM, jhinak sen <jhinak.sen at gmail.com> wrote:
>
>> hi,
>> i am a beginner in python language,
>>
>> i am trying with this programme :
>> to find the addition and mean from a data set in a file and writing the
>> mean and sum in some other file :
>> ""
>> *#! /usr/bin/env python
>>
>> import re
>> import cPickle as p
>> import math
>> from numpy import *
>>
>> f0= open("temp9","r+").readlines()
>> f2= open("out1","r+")
>> add_1=[ ];
>> for i in range(0, len(f0)):
>>         f1=f0[i].split()
>>         add= float(f1[1])+float(f1[2])
>>     mean= float(add)/2
>>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
>> repr(mean).ljust(7)
>>         add_1.append(add)
>>     add_1.append(mean)
>>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
>> repr(mean).ljust(7))
>> print "printing from file"
>> for i in range(0, len(add_1),2):
>>         print add_1[i],"        ", add_1[i+1]
>>
>> f0.close()
>> f2.close()*
>>
>>
>> ""
>>
>> and this programme is givving me this error :
>>
>> ""    *Traceback (most recent call last):
>>   File "./temporary1.py", line 24, in <module>
>>     f0.close()
>> AttributeError: 'list' object has no attribute 'close'*
>> ""
>>
>> please help to to find the error.
>> or suggest some simpler or better way
>>
>> note:
>> 1)file "temp9" is already exist
>> 2)this programme is giving me all my outputs, but at the end of the out
>> ..its giving me that error.
>>
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>
>>
>
>
> ---------- Forwarded message ----------
> From: Sebastian Schabe <sebastian.schabe at gmx.de>
> To: python-list at python.org
> Date: Fri, 10 Jul 2009 12:01:51 +0200
> Subject: Re: Concatenating images (numpy arrays), but they look like HSV
> images
> Robert Kern schrieb:
>
>> Probably, you need to use zeros(..., dtype=uint8). When you use dtype=int,
>> that will result in dtype=int arrays. I suspect that matplotlib is then
>> interpreting that to mean that you want it to treat the input as scalar data
>> (which it will pass through a colormap) rather than an RGB image.
>>
>>
> Thanks Robert, that was exactly the problem. Now I'am really wondering how
> one can know such details. Well, with your answer I searched again in the
> mathplotlib documentation and under the function imshow(X, ...) I indeed
> found the hint, that X has to be an uint8 or float array or PIL image, but
> before I hadn't known where to search.
>
> So again, thank you
>
> Sebastian
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/5e8c298d/attachment-0001.html>

From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 10 06:38:49 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 10 Jul 2009 12:38:49 +0200
Subject: property using a classmethod
In-Reply-To: <4a55db9e$0$10243$426a74cc@news.free.fr>
References: <7a23c6d9-509e-4662-bcb1-1923d893d057@g31g2000yqc.googlegroups.com>
	<4a55db9e$0$10243$426a74cc@news.free.fr>
Message-ID: <4a571a39$0$29561$426a74cc@news.free.fr>

Bruno Desthuilliers a ?crit :
(snip)
> You could write your own custom descriptor. Or just use an additional 
> level of indirection, ie:
> 
>    myProperty = property(lambda self: self.myClassMethod())
> 

Sorry, looks like I didn't read carefully enough. The above code won't 
work if you intend to lookup the property directly on the class object, 
ie "MyClass.myProperty". If that was your intention, you'll need a 
custom descriptor. The following code should do the job, or at least get 
you started:

# python 2.5.x

# the custom (non binding) descriptor
class ClsProperty(object):
     def __init__(self, fget):
         if not isinstance(fget, (classmethod, staticmethod)):
             # XXX better error message
             raise ValueError(
               "fget must be a classmethod or staticmethod"
             )
         self.fget = fget

     def __get__(self, obj, cls=None):
         if cls is None:
             assert obj is not None
             cls = type(obj)
         return self.fget.__get__(obj, cls)()

# helper -> a simple decorator
def classproperty(func):
     if not isinstance(func, (classmethod, staticmethod)):
         func = classmethod(func)
     return ClsProperty(func)


# example use
class Foo(object):

     # the hard way
     @classmethod
     def bar(cls):
         return "%s.bar" % cls.__name__

     quux = ClsProperty(bar)

     # the simple way
     @classproperty
     def baaz(cls):
         return "%s.baaz" % cls


Given your example, this should be enough. If you need a binding 
descriptor (one with a setter), you'll have to implement the __set__ 
method (and possibly __del__). Google for "python descriptor" to find 
more doc about the descriptor protocol.

HTH


From mail at microcorp.co.za  Fri Jul 10 06:54:21 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 10 Jul 2009 12:54:21 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <001401ca014c$ca414d60$0d00a8c0@Hendrik>

"Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:

>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>
>>> persistent idea "out there" that programming is a very accessible
>>> skill, like cooking or gardening, anyone can do it, and even profit
>>> from it, monetarily or otherwise, etc., and to some extent I am
>> 
>> Programming is not like any other human activity.
>
>In practice? In principle? Programming in principle is not the same as it 
>is performed in practice.
>
>But in either case, programming requires both the logical reasoning of 
>mathematics and the creativity of the arts. Funnily enough, 

I do not buy this arty creativity stuff. - or are you talking about
making a website look pretty?

>mathematicians will tell you that mathematics requires the same, and so 
>will the best artists. I think mathematicians, engineers, artists, even 
>great chefs, will pour scorn on your claim that programming is not like 
>any other human activity.

So a chef is now an authority on programming?

Programming is actually kind of different - almost everything else is 
just done, at the time that you do it.

Programming is creating stuff that is completely useless until it is
fed into something that uses it, to do something else, in conjuction
with the thing it is fed into, at a later time.

This is a highly significant difference, IMHO.


>
>
>[...]
>> He talks about how "when all is said and done, the only thing computers
>> can do for us is to manipulate symbols and produce results of such
>> manipulations" and he emphasises the "uninterpreted" nature of
>> mechanical symbol manipulation, i.e. that the machine is doing it
>> mindlessly.
>
>"Manipulate symbols" is so abstract as to be pointless. By that 
>reasoning, I can build a "computer" consisting of a box open at the top. 
>I represent a symbol by an object (say, a helium-filled balloon, or a 
>stone), instead of a pattern of bits. I manipulate the symbol by holding 
>the object over the box and letting go. If it flies up into the sky, that 
>represents the symbol "Love is War", if it falls into the box, it 
>represents the symbol "Strength is Blue", and if it just floats there, it 
>represents "Cheddar Cheese". This is a deterministic, analog computer 
>which manipulates symbols. Great.
>
>And utterly, utterly useless. So what is my computer lacking that real 
>computers have? When you have answered that question, you'll see why 
>Dijkstra's claim is under-specified.
>

So if computers do not manipulate symbols, what is it that they do?
They sure cannot think,
or drink,
or reason,
or almost any verb you can think of.

"Manipulating symbols" is actually an elegant definition.
Try coming up with a better one and you will see.

And calling an abstraction pointless kind of contradicts
what you say later...

8<------- camel humps and other stuff -------------------

- Hendrik





From gabriel.rossetti at arimaz.com  Fri Jul 10 07:09:28 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 10 Jul 2009 13:09:28 +0200
Subject: Threading.Condition problem
In-Reply-To: <4A571083.8030403@arimaz.com>
References: <4A571083.8030403@arimaz.com>
Message-ID: <4A572168.90201@arimaz.com>

The previous msg w/ attached code is the wrong code, please use the code 
attached to this msg, thank you and sorry for this.

Gabriel


Gabriel Rossetti wrote:
> Hello everyone,
>
> I wrote a small example that listens for xmpp msgs in a thread. The 
> main program calls a function that blocks (using Condition.wait) until 
> a msg has been received and then returns the msg. When a msg arrives, 
> it is put in a variable in the thread's object, it then calls the 
> notify() attr on the Condition object. For some reason, this doesn't 
> work, the thread gets the msg, tries to notify the Condition object, 
> fails because the lock has not been acquired yet and blocks. I tried 
> ignoring the failure, thinking that since it has not been acquired yet 
> then when it is, it will get the msg right away and never call 
> Condition.wait, thus not causing any problems, but this does not work 
> either. Does someone know what I am doing wrong? I attached the code 
> to this msg.
>
> Thank you,
> Gabriel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: test_xmpp.py
Type: text/x-python
Size: 1878 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/e8c8f701/attachment-0001.py>

From gabriel.rossetti at arimaz.com  Fri Jul 10 07:09:42 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 10 Jul 2009 13:09:42 +0200
Subject: Threading.Condition problem
Message-ID: <4A572176.9070100@arimaz.com>

Sorry if this appears twice, I sent it once with an attachment and it 
never arrived so maybe the attachment is posing problems. I inlined the 
code this time (at the bottom), thank you,

Gabriel

########################## Original message ############################

Hello everyone,

I wrote a small example that listens for xmpp msgs in a thread. The main
program calls a function that blocks (using Condition.wait) until a msg
has been received and then returns the msg. When a msg arrives, it is
put in a variable in the thread's object, it then calls the notify()
attr on the Condition object. For some reason, this doesn't work, the
thread gets the msg, tries to notify the Condition object, fails because
the lock has not been acquired yet and blocks. I tried ignoring the
failure, thinking that since it has not been acquired yet then when it
is, it will get the msg right away and never call Condition.wait, thus
not causing any problems, but this does not work either. Does someone
know what I am doing wrong? I attached the code to this msg.

Thank you,
Gabriel



############################ Example code ############################

from __future__ import with_statement
import xmpp, sys
from threading import Thread, Condition, Event


class Listener(Thread):
     def __init__(self, ws):
         Thread.__init__(self)
         self.interrupt = Event()
         self.message = None
         self._cv = ws._cv
         self.client = ws._client
         self.client.RegisterHandler('message', self.onMessage)

     def onMessage(self, conn, msg):
         self.message = msg
         try:
             self._cv.notify()
         except RuntimeError:
             print "self._cv has not acquired the lock yet"

     def getMsg(self):
         return self.message

     def run(self):
         try:
             while(not self.interrupt.isSet()):
                 self.client.Process(1)
         except KeyboardInterrupt:
             return 0

class WS(object):
     def __init__(self, username, password, res):
         self._jid = xmpp.protocol.JID(username)
         self._client = xmpp.Client(self._jid.getDomain())
         self._cv = Condition()

         if(self._client.connect(server=("localhost", 5222)) == ""):
             raise Exception("Error while connecting!")

         if(self._client.auth(self._jid.getNode(), password, res) is None):
             raise Exception("Authentication failed!")

         self._client.sendInitPresence()

         self._listener = Listener(self)
         self._listener.start()

     def getMsg(self, mid=None):
         """
         """
         with self._cv:
             res = self._listener.getMsg()
             while not res:
                 self._cv.wait()
                 res = self._listener.getMsg()
             return res

if(__name__ == "__main__"):
     ws = WS("test at localhost", "123", "test")
     res = ws.getMsg()
     print "I just received : %s" % str(res)
     sys.exit(0)




From ben+python at benfinney.id.au  Fri Jul 10 07:30:41 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 10 Jul 2009 21:30:41 +1000
Subject: subprocess + python-daemon - bug/problem?
References: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>
	<828acd8d-a9bd-4506-b695-e537af4587d8@l31g2000yqb.googlegroups.com>
Message-ID: <873a94ojvi.fsf@benfinney.id.au>

Andy  Clegg <andy2.0 at gmail.com> writes:

> "import daemon
> import subprocess
> 
> daemon.DaemonContext(stderr = open("fakeConsole.txt","w+")).open()
> subprocess.Popen(['echo','1']).wait()"
> 
> However the error remains the same.

The error appears in the file specified for the stderr output of the
DaemonContext. Here it is without the unwanted extra line-wrapping that
seems to plague all Google Mail users (seriously, folks: get a real mail
provider that won't mangle your messages)::

    Traceback (most recent call last):
      File "/home/bignose/Projects/python/python-daemon/bin/andy-clegg-test", line 7, in <module>
        subprocess.Popen(['echo', '1']).wait()
      File "/usr/lib/python2.5/subprocess.py", line 1184, in wait
        pid, sts = self._waitpid_no_intr(self.pid, 0)
      File "/usr/lib/python2.5/subprocess.py", line 1014, in _waitpid_no_intr
        return os.waitpid(pid, options)
    OSError: [Errno 10] No child processes

I confirm that I'm getting the same error; Python 2.5.4.

My first thought was perhaps it's related to the fact that the process
has no stdout? But setting ?stdout? and ?stderr? to the same file::

    #! /usr/bin/python

    import daemon
    import subprocess

    fake_console = open("fake_console.txt", "w+")
    daemon.DaemonContext(stdout=fake_console, stderr=fake_console).open()
    subprocess.Popen(['echo', '1']).wait()

still gives the same error::

    1
    Traceback (most recent call last):
      File "/home/bignose/Projects/python/python-daemon/bin/andy-clegg-test", line 8, in <module>
        subprocess.Popen(['echo', '1']).wait()
      File "/usr/lib/python2.5/subprocess.py", line 1184, in wait
        pid, sts = self._waitpid_no_intr(self.pid, 0)
      File "/usr/lib/python2.5/subprocess.py", line 1014, in _waitpid_no_intr
        return os.waitpid(pid, options)
    OSError: [Errno 10] No child processes

I'm not familiar enough with the nuances of the ?subprocess? module to
know what might be going wrong here. I'd like to know whether it might
be a problem in the ?python-daemon? library.

-- 
 \     ?Whatever a man prays for, he prays for a miracle. Every prayer |
  `\   reduces itself to this: ?Great God, grant that twice two be not |
_o__)                                           four.?? ?Ivan Turgenev |
Ben Finney


From vox2000 at gmail.com  Fri Jul 10 07:46:52 2009
From: vox2000 at gmail.com (vox)
Date: Fri, 10 Jul 2009 04:46:52 -0700 (PDT)
Subject: Query regarding set([])?
Message-ID: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>

Hi,
I'm contsructing a simple compare-script and thought I would use set
([]) to generate the difference output. But I'm obviosly doing
something wrong.

file1 contains 410 rows.
file2 contains 386 rows.
I want to know what rows are in file1 but not in file2.

This is my script:
s1 = set(open("file1"))
s2 = set(open("file2"))
s3 = set([])
s1temp = set([])
s2temp = set([])

s1temp = set(i.strip() for i in s1)
s2temp = set(i.strip() for i in s2)
s3 = s1temp-s2temp

print len(s3)

Output is 119. AFAIK 410-386=24. What am I doing wrong here?

BR,
Andy


From davea at ieee.org  Fri Jul 10 07:48:49 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 07:48:49 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <h35a1h$gus$1@ger.gmane.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>	<4A55F392.3080404@ieee.org>
	<h35a1h$gus$1@ger.gmane.org>
Message-ID: <4A572AA1.7010207@ieee.org>

Terry Reedy wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
>> m.reddy prasad reddy wrote:
>>> can any one tell me how to write assembly language programs in 
>>> python...if
>>> no is there any other way to write the programs in python
>>>
>>> Reddi prasad reddy
>>> ph.no:09958083797
>>>
>>>   
>> Assembly language is a different programming language than Python.  
>> You can use both in the same process, much in the same way you can 
>> use C or C++ with Python.  In fact, some of the system DLL's are 
>> written (partly) in assembler, though mostly in C or C++.
>
> It is possible that he meant how to write assembly *with* python.
> Or how to translate python to assembly.
>
> As it turns out, CPython translates Python to byte code and has a dis 
> (assembly) module that produces very nice assembly code ;-)
> So that is one answer to his question.
>
>> You'll need to tell us what your real goal is.
>
> Definitely.
>
> tjr
>
>
> </div>
>
If you mean dis.dis() that only gives you byte code.  I assumed he was 
referring to native code assembly.

I guess I'd better stop guessing <grin>.

DaveA



From __peter__ at web.de  Fri Jul 10 08:04:35 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 14:04:35 +0200
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
Message-ID: <h37aod$i9p$02$1@news.t-online.com>

vox wrote:

> I'm contsructing a simple compare-script and thought I would use set
> ([]) to generate the difference output. But I'm obviosly doing
> something wrong.
> 
> file1 contains 410 rows.
> file2 contains 386 rows.
> I want to know what rows are in file1 but not in file2.
> 
> This is my script:
> s1 = set(open("file1"))
> s2 = set(open("file2"))

Remove the following three lines:

> s3 = set([])
> s1temp = set([])
> s2temp = set([])

 
> s1temp = set(i.strip() for i in s1)
> s2temp = set(i.strip() for i in s2)
> s3 = s1temp-s2temp
> 
> print len(s3)
> 
> Output is 119. AFAIK 410-386=24. What am I doing wrong here?

You are probably misinterpreting len(s3). s3 contains lines occuring in 
"file1" but not in "file2". Duplicate lines are only counted once, and the 
order doesn't matter. 

So there are 119 lines that occur at least once in "file2", but not in 
"file1".

If that is not what you want you have to tell us what exactly you are 
looking for.

Peter



From paul at boddie.org.uk  Fri Jul 10 08:07:21 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Fri, 10 Jul 2009 05:07:21 -0700 (PDT)
Subject: psyco V2 beta2 benchmark
References: <h2nhhs$g5m$00$1@news.t-online.com>
	<mailman.2930.1247194493.8015.python-list@python.org>
Message-ID: <35dcc79b-4f9d-4f16-942e-7cee2a470844@t13g2000yqt.googlegroups.com>

On 10 Jul, 04:54, Zac Burns <zac... at gmail.com> wrote:
> Where do you get this beta? I heard that Psyco V2 is coming out but
> can't find anything on their site to support this.

I found the Subversion repository from the Psyco site:

http://psyco.sourceforge.net/

-> http://codespeak.net/svn/psyco/dist/

-> http://codespeak.net/svn/psyco/v2/

It's not widely advertised, but I imagine that this is the correct
repository. Navigating around on the codespeak.net site took me to the
ViewVC instance which gives some date/time information that would
confirm my suspicions:

https://codespeak.net/viewvc/psyco/

A log of the development can be viewed here:

https://codespeak.net/viewvc/psyco/v2/dist/?view=log

Paul


From mondi at cs.unibo.it  Fri Jul 10 08:10:04 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Fri, 10 Jul 2009 12:10:04 +0000
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <mailman.2929.1247192119.8015.python-list@python.org>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
Message-ID: <h373dq$hpn$1@lec.cs.unibo.it>

Roger Binns wrote:
> jacopo mondi wrote:
>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>> add support to an experimental socket family.
> 
> You may find it considerably easier to use ctypes since that will avoid
> the need for any patching.  You'll also be able to control how read and
> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
> os.fdopen to convert your raw file descriptor into a Python file object
> if appropriate.
> 
> If you do use ctypes then you'll only need to distribute pure Python
> source code.
> 
> Roger
Thanks a lot, I'll give it a try..

cheers
	jacopo


From rhodri at wildebst.demon.co.uk  Fri Jul 10 08:22:31 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 10 Jul 2009 13:22:31 +0100
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <op.uwupztjca8ncjz@gnudebst>

On Fri, 10 Jul 2009 10:41:03 +0100, jhinak sen <jhinak.sen at gmail.com>  
wrote:

> hi,
> i am a beginner in python language,
>
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the  
> mean
> and sum in some other file :
> ""
> *#! /usr/bin/env python
>
> import re
> import cPickle as p
> import math
> from numpy import *
>
> f0= open("temp9","r+").readlines()
> f2= open("out1","r+")
> add_1=[ ];
> for i in range(0, len(f0)):
>         f1=f0[i].split()
>         add= float(f1[1])+float(f1[2])
>     mean= float(add)/2
>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
> repr(mean).ljust(7)
>         add_1.append(add)
>     add_1.append(mean)
>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
> repr(mean).ljust(7))
> print "printing from file"
> for i in range(0, len(add_1),2):
>         print add_1[i],"        ", add_1[i+1]
>
> f0.close()
> f2.close()*
>
>
> ""
>
> and this programme is givving me this error :
>
> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""

As the error message tells you, 'f0' is a list.  readlines()
returns a list of the lines in the file object, rather than the
file object itself.  Since you promptly (and entirely reasonably)
discard the file object, you haven't got any way to close() it.

You don't actually need to do that, though.  You can use a file
object as something you use a 'for' loop over, and be given one
line at a time.  So instead you can write your code like this:

<snippet>
f0 = open("temp9", "r")
for line in f0:
     f1 = line.split()
     # ... and so on
</snippet>

Notice that I only opened the file as "r" -- you are only
reading it, not updating it, and giving yourself more permission
than you need is a bad habit to get into.  Opening the file this
way means that if you accidentally write f0.write("something")
instead of "f2.write(something)", Python will stop you with an
exception rather than silently trash your data.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Fri Jul 10 08:25:49 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 10 Jul 2009 13:25:49 +0100
Subject: need to write a assembly progrm
In-Reply-To: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
References: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
Message-ID: <op.uwup5bama8ncjz@gnudebst>

On Thu, 09 Jul 2009 11:52:44 +0100, m.reddy prasad reddy  
<reddy.mrp at gmail.com> wrote:

> my aim is to run the assembly programs in python.by that we can use that  
> in
> the any labs.because we can run the python in the mobiles also.if we  
> write
> assembly programs in the mobile ,the mobile act as a tool kit for the
> lab.tell me any other solutions for this

Please define what you mean by "assembly".

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From mtnbikingmark at gmail.com  Fri Jul 10 08:30:46 2009
From: mtnbikingmark at gmail.com (Mark)
Date: Fri, 10 Jul 2009 05:30:46 -0700 (PDT)
Subject: Examples of Python driven Microsoft UI Automation wanted
References: <0e99f569-e5ab-42d5-8393-9918a7dc34cb@n11g2000yqb.googlegroups.com>
	<ZDp5m.8132$Rb6.7418@flpi147.ffdc.sbc.com>
	<558d5613-ca3d-46ff-8dbe-0239f5acaad3@o7g2000yqb.googlegroups.com>
	<J0q5m.8136$Rb6.4889@flpi147.ffdc.sbc.com>
	<e77d2670-2c64-4ae4-8257-f7904ca3fe71@b15g2000yqd.googlegroups.com>
	<d083acfe-99b7-45c9-8ed4-fd482c8ce147@o9g2000prg.googlegroups.com> 
	<ff67eeab-48d1-40a5-8870-666944c8c7f2@q11g2000yqi.googlegroups.com> 
	<d6bc18b8-f74e-40cb-ba9f-1be8386f2fc6@s31g2000yqs.googlegroups.com>
Message-ID: <3aa3398a-b944-40fc-bb3b-2c2650d41454@26g2000yqk.googlegroups.com>

Hi,

I am the author of pywinauto (http://pywinauto.openqa.org/).

It doesn't have specific functionality built in for winforms - but
many winforms controls are built on top of win32 functionality and
pywinauto can work with them for that.

On Jul 9, 4:41?pm, Paul McGuire <pt... at austin.rr.com> wrote:
> On Jul 9, 1:50?pm, DuaneKaufman <duane.kauf... at gmail.com> wrote:
>
> > > I have used pywinauto to drive a Flash game running inside of an
> > > Internet Explorer browser - that's pretty GUI!
>

Wow - cool :)


> > > -- Paul
>
> > Hi,
>
> > Could you share some code examples?
>

You might have a look at http://pywinauto.pbworks.com/ (the site is no
longer used - but there is a cool movie giving an example of using
pywinauto at the interactive prompt)

Other examples (Notepad, mspaint) are included with the install.

PyPi - http://pypi.python.org/pypi/pywinauto/0.3.8


> > Thanks,
> > Duane (duanek (at) chorus (dot) net)
>

Good luck! :)
  Mark

> I just went on a brief fishing expedition through two disk backups,
> and no luck. ?I guess it's been a while since I worked on this.
>
> The work I did was entirely graphical, which is to say, my script
> interacted with the Flash program by using PIL to take image snapshots
> of the window, and then sifting through the bitmap looking for the
> status of a "time remaining" thermometer-style gauge in the game.
> Then the script could click on X-Y coordinates within the window,
> which would get picked up by the Flash game, and the script would
> monitor the "time remaining" gauge some more, and so on.
>
> I'm not sure how well pywinauto would work in allowing you to access
> controls such as textboxes within a form. ?I remember that I had to
> access the IE window using a caption name, and then found the embedded
> Flash program as an embedded control of some sort, again, I probably
> needed to indicate that it was some sort of "Adobe.FlashWidget1"
> object or something.
>
> I may have another, older disk backup at home, I can look for it later
> this evening.
>
> -- Paul



From jeanmichel at sequans.com  Fri Jul 10 08:32:52 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 10 Jul 2009 14:32:52 +0200
Subject: language analysis to enforce code standards
In-Reply-To: <pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
References: <mailman.9989.1246930194.8014.python-list@python.org>	<mailman.2927.1247192026.8015.python-list@python.org>
	<pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A5734F4.7010105@sequans.com>

Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 02:06:35 +0000, Jason S. Friedman wrote:
>
>   
>> Hello, I administer the Informatica ETL tool at my company.  Part of
>> that role involves creating and enforcing standards.  I want the
>> Informatica developers to add comments to certain key objects and I want
>> to be able to verify (in an automated fashion) that they have done so.
>>
>> I cannot merely check for non-emptiness; that is trivial to circumvent.
>>   On the other hand, I probably do not need to be able to catch
>> developers who are determined to not create comments.  There are not too
>> many of them and perhaps they will find it is easier to write a (useful)
>> comment than to game the system.
>>
>> Any thoughts on how I might proceed?  Stated plainly, how can I tell
>> when a string more-or-less forms at least one phrase?
>>     
>
> Define "phrase".
>
>
> if len(s) > 0:
>     print "at least one character"
> if len(s.split()) > 0:
>     print "at least one word"
> if len(s.split('\n') > 0:
>     print "at least one line"
>
>
>
>   
You could also verify there are at least N different characters used in 
the sentence:

N = 5 # must contains at least 5 different characters
record = []
for c in s:
    if c not in record:
        record += [c]
if len(record) >= N:
    print "at least %s different characters" % N


Jean-Michel


From python.list at tim.thechases.com  Fri Jul 10 08:37:59 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 10 Jul 2009 07:37:59 -0500
Subject: can i write a assemly language programs in python
In-Reply-To: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
Message-ID: <4A573627.8090308@tim.thechases.com>

m.reddy prasad reddy wrote:
> can any one tell me how to write assembly language programs in python...if
> no is there any other way to write the programs in python

Bah, writing assembly language is easy in Python:

   print("MOV EAX, [EBX]")
   print("XOR EBX, EBX")

Just adjust the strings for your favorite processor architecture 
and Python will produce the assembly code you want.

Now compiling assembly to *machine* code...or calling between 
Python and assembly...that's another matter.  But writing 
assembly language programs in Python?  Easy. ;-)

-tkc





From __peter__ at web.de  Fri Jul 10 08:48:18 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 14:48:18 +0200
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
Message-ID: <h37dac$cfk$00$1@news.t-online.com>

Jason S. Friedman wrote:

> Hello, I administer the Informatica ETL tool at my company.  Part of
> that role involves creating and enforcing standards.  I want the
> Informatica developers to add comments to certain key objects and I want
> to be able to verify (in an automated fashion) that they have done so.
> 
> I cannot merely check for non-emptiness; that is trivial to circumvent.
>   On the other hand, I probably do not need to be able to catch
> developers who are determined to not create comments.  There are not too
> many of them and perhaps they will find it is easier to write a (useful)
> comment than to game the system.
> 
> Any thoughts on how I might proceed?  Stated plainly, how can I tell
> when a string more-or-less forms at least one phrase?

Don't be a fool. Have someone other than the author read the comment.

Peter



From vox2000 at gmail.com  Fri Jul 10 08:52:10 2009
From: vox2000 at gmail.com (vox)
Date: Fri, 10 Jul 2009 05:52:10 -0700 (PDT)
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
Message-ID: <3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>

On Jul 10, 2:04?pm, Peter Otten <__pete... at web.de> wrote:
> You are probably misinterpreting len(s3). s3 contains lines occuring in
> "file1" but not in "file2". Duplicate lines are only counted once, and the
> order doesn't matter.
>
> So there are 119 lines that occur at least once in "file2", but not in
> "file1".
>
> If that is not what you want you have to tell us what exactly you are
> looking for.
>
> Peter

Hi,
Thanks for the answer.

I am looking for a script that compares file1 and file2, for each line
in file1, check if line is present in file2. If the line from file1 is
not present in file2, print that line/write it to file3, because I
have to know what lines to add to file2.

BR,
Andy





From drobinow at gmail.com  Fri Jul 10 09:10:14 2009
From: drobinow at gmail.com (David Robinow)
Date: Fri, 10 Jul 2009 09:10:14 -0400
Subject: Query regarding set([])?
In-Reply-To: <3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
Message-ID: <4eb0089f0907100610j3c53f4efjae119c9ec21f3992@mail.gmail.com>

On Fri, Jul 10, 2009 at 8:52 AM, vox<vox2000 at gmail.com> wrote:
> I am looking for a script that compares file1 and file2, for each line
> in file1, check if line is present in file2. If the line from file1 is
> not present in file2, print that line/write it to file3, because I
> have to know what lines to add to file2.
  Just copy file1 to file2.
(I'm pretty sure that's not what you want, but in explaining why it
should become clearer what you're trying to do.)


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 09:11:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 13:11:09 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
Message-ID: <007318de$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 12:54:21 +0200, Hendrik van Rooyen wrote:

> "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
> 
>>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>>
>>>> persistent idea "out there" that programming is a very accessible
>>>> skill, like cooking or gardening, anyone can do it, and even profit
>>>> from it, monetarily or otherwise, etc., and to some extent I am
>>> 
>>> Programming is not like any other human activity.
>>
>>In practice? In principle? Programming in principle is not the same as
>>it is performed in practice.
>>
>>But in either case, programming requires both the logical reasoning of
>>mathematics and the creativity of the arts. Funnily enough,
> 
> I do not buy this arty creativity stuff. - or are you talking about
> making a website look pretty?

I must admit, it never crossed my mind that anyone here would claim that 
there was no creativity involved in programming, that it was all a 
mindless, algorithmic process capable of being done by a simple 
mechanical device.

This is certainly the accusation made against *bad* programmers -- that 
they can't actually solve new, unique problems, but just apply recipes 
they learned without any insight or intelligence. The sort of people who 
program so poorly that "a trained monkey could do what they do".

Do you really think that applies to good programmers too? If so, then a 
good code generator should be able to replace any programmer. Is that 
what you believe?


 
>>mathematicians will tell you that mathematics requires the same, and so
>>will the best artists. I think mathematicians, engineers, artists, even
>>great chefs, will pour scorn on your claim that programming is not like
>>any other human activity.
> 
> So a chef is now an authority on programming?

Did I say that?

Chefs are authorities on OTHER HUMAN ACTIVITIES.



> Programming is actually kind of different - almost everything else is
> just done, at the time that you do it.
> 
> Programming is creating stuff that is completely useless until it is fed
> into something that uses it, to do something else, in conjuction with
> the thing it is fed into, at a later time.

Somebody should teach Hendrik that human beings have been creating TOOLS 
for hundreds of thousands of years. People have been creating tools to 
build tools for thousands of years. Software is just more of the same.

Even *soup stock* fits the same profile as what Hendrik claims is almost 
unique to programming. On its own, soup stock is totally useless. But you 
make it, now, so you can you feed it into something else later on.

Or instant coffee.

No, Henrik, if that's the best you can do, it's not very good. It is 
rather sad, but also hilarious, that the most different thing you have 
noticed about software is that it's just like instant coffee.


> This is a highly significant difference, IMHO.


>>[...]
>>> He talks about how "when all is said and done, the only thing
>>> computers can do for us is to manipulate symbols and produce results
>>> of such manipulations" and he emphasises the "uninterpreted" nature of
>>> mechanical symbol manipulation, i.e. that the machine is doing it
>>> mindlessly.
>>
>>"Manipulate symbols" is so abstract as to be pointless. By that
>>reasoning, I can build a "computer" consisting of a box open at the top.
>>I represent a symbol by an object (say, a helium-filled balloon, or a
>>stone), instead of a pattern of bits. I manipulate the symbol by holding
>>the object over the box and letting go. If it flies up into the sky,
>>that represents the symbol "Love is War", if it falls into the box, it
>>represents the symbol "Strength is Blue", and if it just floats there,
>>it represents "Cheddar Cheese". This is a deterministic, analog computer
>>which manipulates symbols. Great.
>>
>>And utterly, utterly useless. So what is my computer lacking that real
>>computers have? When you have answered that question, you'll see why
>>Dijkstra's claim is under-specified.
>>
>>
> So if computers do not manipulate symbols, what is it that they do?

Did I say they don't manipulate symbols?


> They
> sure cannot think,
> or drink,
> or reason,

They can't reason? Then what are they doing when they manipulate symbols?

Yet again, it didn't even cross my mind that somebody would make this 
claim. My entire point is that it's not enough to just "manipulate 
symbols", you have to manipulate symbols the correct way, following laws 
of logic, so that the computer can *mindlessly* reason.


> or almost any verb you can think of.

If you're going to take that argument, then I'll remind you that there 
are no symbols inside a computer. There are only bits. And in fact, there 
aren't even any bits -- there are only analog voltages, and analog 
magnetic fields.


> "Manipulating symbols" is actually an elegant definition. Try coming up
> with a better one and you will see.

As I said above, it's not enough to just manipulate symbols. Here's a set 
of rules to manipulate symbols:

X => 0

or in English, "Any symbol becomes the zero symbol".

That's symbol manipulation. Utterly useless. This is why it's not enough 
to just manipulate symbols, you have to manipulate them THE RIGHT WAY.



-- 
Steven


From david250 at videotron.ca  Fri Jul 10 09:14:50 2009
From: david250 at videotron.ca (David Bernier)
Date: Fri, 10 Jul 2009 09:14:50 -0400
Subject: AP  -- MeAmI.org Paces Google
In-Reply-To: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
Message-ID: <h37esb0ng0@news7.newsguy.com>

Musatov wrote:
> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> its adopted use in Pakistan.  The search engine has grown in
> popularity 10,000 fold following its Beta test launch three months ago
> in April, 2009. Supporters of the site claim it is better than rival
> Google upon which platform it is based. Controversy arose after
> MeAmI.org search code allowed users to search other users Google
> results with no advertising. "It is truly an innovative thing we are
> doing," said Founder and CEO, Martin Musatov. "Letting users search
> the results of other Google users immediately results in a level of
> accuracy and relevance above and beyond Google." Google changed their
> API following the launch or MeAmI.org and explored the possibility of
> blocking site access from MeAmI.org to Google search results but was
> unable to do so. Critics of MeAmI.org say what it is doing is
> tantamount to intellectual theft. When asked about this topper Musatov
> exclaimed, "The Internet was made for people, not companies." An
> analyst at Goldman Sachs says, requesting to remain anonymous,
> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> global activism and to tell you the truth, this makes it much more
> likely an acquisition target than potential intellectual property
> violator." Google could not be reached for comment.

Mr. Musatov, is it you who removed the post
quoted above from the Google Groups archive?

Thank you.

David Bernier


From Nikolaus at rath.org  Fri Jul 10 09:22:29 2009
From: Nikolaus at rath.org (Nikolaus Rath)
Date: Fri, 10 Jul 2009 09:22:29 -0400
Subject: Implementing a cache
Message-ID: <87ab3cwu3u.fsf@vostro.rath.org>

Hello,

I want to implement a caching data structure in Python that allows me
to:

 1. Quickly look up objects using a key
 2. Keep track of the order in which the objects are accessed (most
    recently and least recently accessed one, not a complete history)
 3. Quickly retrieve and remove the least recently accessed object.


Here's my idea for the implementation:

The objects in the cache are encapsulated in wrapper objects:

class OrderedDictElement(object):
    __slots__ = [ "next", "prev", "key", "value" ]

These wrapper objects are then kept in a linked lists and in an ordinary
dict (self.data) in parallel. Object access then works as follows:

    def __setitem__(self, key, value):
        if key in self.data:
            # Key already exists, just overwrite value
            self.data[key].value = value
        else:
            # New key, attach at head of list
            with self.lock:
                el = OrderedDictElement(key, value, next=self.head.next, prev=self.head)
                self.head.next.prev = el
                self.head.next = el
                self.data[key] = el

    def __getitem__(self, key):
        return self.data[key].value
    
To 'update the access time' of an object, I use
    
    def to_head(self, key):
        with self.lock:
            el = self.data[key]
            # Splice out
            el.prev.next = el.next
            el.next.prev = el.prev
            
            # Insert back at front
            el.next = self.head.next
            el.prev = self.head
            
            self.head.next.prev = el
            self.head.next = el
        

self.head and self.tail are special sentinel objects that only have a
.next and .prev attribute respectively.


While this is probably going to work, I'm not sure if its the best
solution, so I'd appreciate any comments. Can it be done more elegantly?
Or is there an entirely different way to construct the data structure
that also fulfills my requirements?


I already looked at the new OrderedDict class in Python 3.1, but
apparently it does not allow me to change the ordering and is therefore
not suitable for my purpose. (I can move something to one end by
deleting and reinserting it, but I'd like to keep at least the option of also
moving objects to the opposite end).


Best,


   -Nikolaus

-- 
 ?Time flies like an arrow, fruit flies like a Banana.?

  PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6  02CF A9AD B7F8 AE4E 425C


From aahz at pythoncraft.com  Fri Jul 10 09:50:29 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 06:50:29 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32eoh$ql8$1@reader1.panix.com>
	<h32fon$264$1@panix3.panix.com> <h32i2o$eop$1@reader1.panix.com>
Message-ID: <h37gv5$r81$1@panix3.panix.com>

[excessive quoting ahead, I'm too tired to trim]

In article <h32i2o$eop$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>In <h32fon$264$1 at panix3.panix.com> aahz at pythoncraft.com (Aahz) writes:
>>In article <h32eoh$ql8$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>>>
>>>OK, so, scratching from my original post the case
>>>
>>><identifier>.<identifier> = <expression>
>>>
>>>(as being a special case of <identifier> = <expression>), still,
>>>to the extent that I understand your post, the "=" in
>>>
>>>  x = 1
>>>
>>>means something fundamentally different (in terms of Python's
>>>underlying implementation) from the "=" in
>>>
>>>  y[0] = 1
>>>
>>>No?
>>
>>No.  ;-)
>
>No???  Just when I thought I finally understood all this!
>
>>What's different is not the ``=`` but the construction of the
>>assignment target before ``=`` gets executed.
>
>Hmm.  OK, I went to the link you posted in your other message
>(http://docs.python.org/reference/simple_stmts.html#assignment-statements)
>and I find this (my emphasis):
>
>    Assignment of an object to a single target is recursively defined as follows.
>
>    * If the target is an identifier (name):
>
>	  o If the name does not occur in a global statement in
>	    the current code block: the name is bound to the object
>                                    ^^^^^^^^^^^^^^^^^
>	    in the current local namespace.
>
>	  o Otherwise: the name is bound to the object in the
>                       ^^^^^^^^^^^^^^^^^
>	    current global namespace.
>
>      The name is rebound if it was already bound. This may cause
>      the reference count for the object previously bound to the
>      name to reach zero, causing the object to be deallocated and
>      its destructor (if it has one) to be called.
>
>    * If the target is a target list enclosed in parentheses or in
>      square brackets... (I'LL IGNORE THIS FOR NOW)
>
>    * If the target is an attribute reference: The primary expression
>      in the reference is evaluated. It should yield an object with
>      assignable attributes; if this is not the case, TypeError is
>      raised. That object is then asked to assign the assigned
>              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      object to the given attribute; if it cannot perform the
>      ^^^^^^
>      assignment, it raises an exception (usually but not necessarily
>      AttributeError).
>
>    * If the target is a subscription: The primary expression in
>      the reference is evaluated. It should yield either a mutable
>      sequence object (such as a list) or a mapping object (such
>      as a dictionary). Next, the subscript expression is evaluated.
>
>      If the primary is a mutable sequence object (such as a
>      list),...  [CONDITIONS ON THE INDEX EXPRESSION OMITTED]...
>      the sequence is asked to assign the assigned object to its
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      item with that index....
>
>      If the primary is a mapping object (such as a dictionary),...
>      [CONDITIONS ON THE SUBSCRIPT EXPRESSION OMITTED]... the
>                                                          ^^^
>      mapping is then asked to create a key/datum pair which maps
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      the subscript to the assigned object.
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>    * If the target is a slicing: [INDEX STUFF OMITTED]... the
>                                                           ^^^
>      sequence object is asked to replace the slice with the items
>      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      of the assigned sequence...
>      ^^^^^^^^^^^^^^^^^^^^^^^^
>
>OK, I originally interpreted what Lundh wrote in his two articles
>that the "binding" described at the very beginning (i.e. when the
>target is an identifier), which I take to make an entry or modify
>such an entry in a namespace, is a *categorically different*
>operation from the remaining operations underlined above.
>
>I interpreted Paul Boddie's correction in his response to me as
>saying that the "assignment" mentioned for the case when the target
>is an attribute reference is actually a special case of the
>"assignment" to simple identifiers (i.e. it also means "binding").
>
>But that still leaves all the other "assignments" (or the like)
>underlined above.  I don't think that the full definitions of these
>remaining cases are covered by the same rule, even though the rule
>is described as "recursive."  I think that the writer has something
>else in mind, and in particular, something *other* than binding,
>but the author remains vague on exactly what this means.
>
>Clearly, both Lundh and the documentation draw some distinction
>between "binding" and some other forms of "assignment" (which remain
>ill-defined throughout).  This distinction is what I was referring
>to when I said that "=" means different things in different contexts.

Consider this:

x = 1
globals()['x'] = 1
locals()[1] = 1

What's the difference between the three?  Although there's a lot of
machinery amenable to manipulation, with the corresponding potential for
breaking the standard model, fundamentally it all comes down to the
intention that *some* piece of code establishes a target on the left-hand
side and binds it to the object returned by the right-hand side.  IME,
except when going down to the very lowest-level details, Python is
easiest to understand when you treat all assignment statements as working
the same.  It helps to remember that names and namespaces are in many
ways syntactic sugar for dicts or lists.

(Obviously, the example with locals() doesn't do what it purports to do,
but it shows how function/method namespaces work under the covers.)

Slicing is the one real exception, but again I think that it's easier to
understand by wedging your mental model into conformance with the simple
target/binding metaphor.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From davea at ieee.org  Fri Jul 10 09:55:58 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 09:55:58 -0400
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <4A57486E.9070900@ieee.org>

jhinak sen wrote:
> hi,
> i am a beginner in python language,
>
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the mean
> and sum in some other file :
> ""
> *#! /usr/bin/env python
>
> import re
> import cPickle as p
> import math
> from numpy import *
>
> f0= open("temp9","r+").readlines()
> f2= open("out1","r+")
> add_1=[ ];
> for i in range(0, len(f0)):
>         f1=f0[i].split()
>         add= float(f1[1])+float(f1[2])
>     mean= float(add)/2
>         print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
> repr(mean).ljust(7)
>         add_1.append(add)
>     add_1.append(mean)
>         f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
> repr(mean).ljust(7))
> print "printing from file"
> for i in range(0, len(add_1),2):
>         print add_1[i],"        ", add_1[i+1]
>
> f0.close()
> f2.close()*
>
>
> ""
>
> and this programme is givving me this error :
>
> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""
>
> please help to to find the error.
> or suggest some simpler or better way
>
> note:
> 1)file "temp9" is already exist
> 2)this programme is giving me all my outputs, but at the end of the out
> ..its giving me that error.
>
>   
Others have pointed out the specific problem that gives you this error.  
But I'd like to point out a few other things to consider:

1) Don't mix tabs and spaces.  Best practice is to bind tab to (4) 
spaces in your editor, and never have a tab in a Python source file.
2) Think about your variable names.  As it stands, f0 is a list of 
lines, f1 is a list of "word" within a line, and f2 is a file.  No 
wonder you accidentally tried to close the list.  I'd suggest things like:
      infile = open(....)
      lines = infile.readlines()
      outfile = open(....)

      for line in lines:
             words = line.split(" ")     or  even   val1, val2 = 
lines.split(" ")

   Then of course the last two lines become
   infile.close()
   outfile.close()

3) Learn to use the for statement directly on a list, rather than using 
len() on the list to make an index, then using the index to find the value
4) On the open() calls, get your modes right.  Looks like you really want
   infile = open(infilename, "r")
   outfile = open(outfilename, "w")
5) Consider using tuples in your add_1 list, rather than separate 
elements.  That way, each element of the list would contain both sum and 
mean.
               add_1.append((add, mean))

       and the final print would become

    for item in add_1:
        print item[0],"        ", item[1]

6) Put anything over three lines into a function, instead of doing it at 
module scope.  That way, you'll be clearer about what things are local 
to this code, and what might be useful to other code in the same module.
In this case,  infilename, and outfilename might be arguments to that 
function.

There are lots of other refinements, but these are all within your 
reach, and would make the program much clearer.



From usernet at ilthio.net  Fri Jul 10 10:05:13 2009
From: usernet at ilthio.net (Tim Harig)
Date: Fri, 10 Jul 2009 14:05:13 GMT
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
Message-ID: <tUH5m.17111$iz2.3737@nlpi070.nbdc.sbc.com>

On 2009-07-10, garabik-news-2005-05 at kassiopeia.juls.savba.sk <garabik-news-2005-05 at kassiopeia.juls.savba.sk> wrote:
> Tim Harig <usernet at ilthio.net> wrote:
>> On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
>>> I would like to learn a way of changing the colour of a particular
>>> part of the output text. I've tried the following
>> On Unix operating systems this would be done through the curses interface:
>> http://docs.python.org/library/curses.html
> Or using ANSI colour codes:

Which will only work for ANSI terminals.


From t.lehmann at rtsgroup.net  Fri Jul 10 10:07:22 2009
From: t.lehmann at rtsgroup.net (Thomas Lehmann)
Date: Fri, 10 Jul 2009 07:07:22 -0700 (PDT)
Subject: Tkinter only: table widget with canvas...
Message-ID: <fc75d14e-41b8-4cc8-ba0b-b2e1a1c04f5e@v20g2000yqm.googlegroups.com>

My intention is to keep dependencies low that means using python and
tkinter
as base package is quite easy because it's available on nearly every
system.

There is good documentation on Tkinter but going into the depth I'm
missing
many details. As an example...

Using the Tkinter.Canvas class I should be able to create a nice
table.
The missing informations are:

a) Assume I would have some different widgets to add per row. How
    do I get the maximum row height?

b) Assume something like a label in one column. The length of all
texts
    in a column will differ. How do I choose the maxium column width?

c) Placing headers in a canvas does not look like a good idea because
    I don't want to scroll the headers. Am I right?
    c.1) How do I place a none scrollable header in a canvas?  or
    c.2) How do I place all headers outside the canvas correctly above
the relating column?

best regards
Thomas


From davea at ieee.org  Fri Jul 10 10:17:55 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 10:17:55 -0400
Subject: Query regarding set([])?
In-Reply-To: <3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
Message-ID: <4A574D93.30103@ieee.org>

vox wrote:
> On Jul 10, 2:04 pm, Peter Otten <__pete... at web.de> wrote:
>   
>> You are probably misinterpreting len(s3). s3 contains lines occuring in
>> "file1" but not in "file2". Duplicate lines are only counted once, and the
>> order doesn't matter.
>>
>> So there are 119 lines that occur at least once in "file2", but not in
>> "file1".
>>
>> If that is not what you want you have to tell us what exactly you are
>> looking for.
>>
>> Peter
>>     
>
> Hi,
> Thanks for the answer.
>
> I am looking for a script that compares file1 and file2, for each line
> in file1, check if line is present in file2. If the line from file1 is
> not present in file2, print that line/write it to file3, because I
> have to know what lines to add to file2.
>
> BR,
> Andy
>
>
>   
There's no more detail in that response.  To the level of detail you 
provide, the program works perfectly.  Just loop through the set and 
write the members to the file.

But you have some unspecified assumptions:
    1) order doesn't matter
    2) duplicates are impossible in the input file, or at least not 
meaningful.  So the correct output file could very well be smaller than 
either of the input files.

And a few others that might matter:
    3) the two files are both text files, with identical line endings 
matching your OS default
    4) the two files are ASCII, or at least 8 bit encoded, using the 
same encoding  (such as both UTF-8)
    5) the last line of each file DOES have a trailing newline sequence





From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 10:22:11 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 14:22:11 GMT
Subject: Implementing a cache
References: <87ab3cwu3u.fsf@vostro.rath.org>
Message-ID: <00732984$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 09:22:29 -0400, Nikolaus Rath wrote:

> Hello,
> 
> I want to implement a caching data structure in Python that allows me
> to:
> 
>  1. Quickly look up objects using a key 2. Keep track of the order in
>  which the objects are accessed (most
>     recently and least recently accessed one, not a complete history)
>  3. Quickly retrieve and remove the least recently accessed object.

Google for "python LRU cache".

Here are the first three hits:

http://code.activestate.com/recipes/498245/
http://code.activestate.com/recipes/252524/
http://www.algorithm.co.il/blogs/index.php/programming/python/small-python-challenge-no-2-lru-cache/




-- 
Steven


From chris at simplistix.co.uk  Fri Jul 10 10:26:00 2009
From: chris at simplistix.co.uk (Chris Withers)
Date: Fri, 10 Jul 2009 15:26:00 +0100
Subject: Where does setuptools live?
In-Reply-To: <59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com>
	<4A52A055.8080108@simplistix.co.uk>	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net>
	<mailman.2759.1246954003.8015.python-list@python.org>
	<59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
Message-ID: <4A574F78.9000801@simplistix.co.uk>

Inky 788 wrote:
> Currently, distutils itself is being actively developed. More info
> about this here: http://tarekziade.wordpress.com/
> 
> My (albeit anonymous) advice is: use distutils. Manually download
> packages as-needed from PyPI and install manually using standard
> distutils.

No thanks. I'm a big fan of buildout. Making it possible for packages to 
specify their dependencies is a big win...

Chris

-- 
Simplistix - Content Management, Zope & Python Consulting
            - http://www.simplistix.co.uk


From vox2000 at gmail.com  Fri Jul 10 10:28:04 2009
From: vox2000 at gmail.com (vox)
Date: Fri, 10 Jul 2009 07:28:04 -0700 (PDT)
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
	<mailman.2952.1247235487.8015.python-list@python.org>
Message-ID: <a8e2285e-f3f4-4d74-95c0-12d2d3156d04@y19g2000yqy.googlegroups.com>

On Jul 10, 4:17?pm, Dave Angel <da... at ieee.org> wrote:
> vox wrote:
> > On Jul 10, 2:04 pm, Peter Otten <__pete... at web.de> wrote:
>
> >> You are probably misinterpreting len(s3). s3 contains lines occuring in
> >> "file1" but not in "file2". Duplicate lines are only counted once, and the
> >> order doesn't matter.
>
> >> So there are 119 lines that occur at least once in "file2", but not in
> >> "file1".
>
> >> If that is not what you want you have to tell us what exactly you are
> >> looking for.
>
> >> Peter
>
> > Hi,
> > Thanks for the answer.
>
> > I am looking for a script that compares file1 and file2, for each line
> > in file1, check if line is present in file2. If the line from file1 is
> > not present in file2, print that line/write it to file3, because I
> > have to know what lines to add to file2.
>
> > BR,
> > Andy
>
> There's no more detail in that response. ?To the level of detail you
> provide, the program works perfectly. ?Just loop through the set and
> write the members to the file.
>
> But you have some unspecified assumptions:
> ? ? 1) order doesn't matter
> ? ? 2) duplicates are impossible in the input file, or at least not
> meaningful. ?So the correct output file could very well be smaller than
> either of the input files.
>
> And a few others that might matter:
> ? ? 3) the two files are both text files, with identical line endings
> matching your OS default
> ? ? 4) the two files are ASCII, or at least 8 bit encoded, using the
> same encoding ?(such as both UTF-8)
> ? ? 5) the last line of each file DOES have a trailing newline sequence

Thanks all for the input!
I have guess I have to think it through a couple times more. :)

BR,
Andy


From digitig at gmail.com  Fri Jul 10 10:38:54 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 10 Jul 2009 15:38:54 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h33k3d$2uu$1@reader1.panix.com>
References: <h2l36k$q5l$1@reader1.panix.com> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
Message-ID: <aee48b3c0907100738o3a4957eej64e0b229ac245d75@mail.gmail.com>

2009/7/9 kj <no.email at please.post>:

> Thanks for the encouragement.

[snip]

> into code. ?And by this I mean not only assumptions about the
> correctness of their code (the typical scope of assertions), but
> also, more broadly, assumptions about the data that they are dealing
> with (which often comes from external sources with abysmal quality
> control).

There we diverge. A lot. If "correctness of the code trumps everything
else" (in fact, if it matters at all) and the external data has
"abysmal quality control" then it *must* be checked for correctness
before it is used. If it is not, you have no idea whether your output
is correct or not. And assertions *will* *not* reliably provide that
checking (because they may not be executed). You *must* actively check
the data, using good old-fasioned "if" statements and so on, because
not to do so is to declare that you *don't* care about correctness.
You *know* the input is often wrong, but you're not bothering to check
it?

-- 
Tim Rowe


From __peter__ at web.de  Fri Jul 10 10:59:53 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 16:59:53 +0200
Subject: Query regarding set([])?
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
	<h37aod$i9p$02$1@news.t-online.com>
	<3b50124d-8f92-43fb-a784-c8516c22579d@h18g2000yqj.googlegroups.com>
	<mailman.2952.1247235487.8015.python-list@python.org>
	<a8e2285e-f3f4-4d74-95c0-12d2d3156d04@y19g2000yqy.googlegroups.com>
Message-ID: <h37l12$prp$03$1@news.t-online.com>

vox wrote:

> On Jul 10, 4:17 pm, Dave Angel <da... at ieee.org> wrote:
>> vox wrote:
>> > On Jul 10, 2:04 pm, Peter Otten <__pete... at web.de> wrote:
>>
>> >> You are probably misinterpreting len(s3). s3 contains lines occuring
>> >> in "file1" but not in "file2". Duplicate lines are only counted once,
>> >> and the order doesn't matter.
>>
>> >> So there are 119 lines that occur at least once in "file2", but not in
>> >> "file1".
>>
>> >> If that is not what you want you have to tell us what exactly you are
>> >> looking for.
>>
>> >> Peter
>>
>> > Hi,
>> > Thanks for the answer.
>>
>> > I am looking for a script that compares file1 and file2, for each line
>> > in file1, check if line is present in file2. If the line from file1 is
>> > not present in file2, print that line/write it to file3, because I
>> > have to know what lines to add to file2.
>>
>> > BR,
>> > Andy
>>
>> There's no more detail in that response.  To the level of detail you
>> provide, the program works perfectly.  Just loop through the set and
>> write the members to the file.
>>
>> But you have some unspecified assumptions:
>> 1) order doesn't matter
>> 2) duplicates are impossible in the input file, or at least not
>> meaningful.  So the correct output file could very well be smaller than
>> either of the input files.
>>
>> And a few others that might matter:
>> 3) the two files are both text files, with identical line endings
>> matching your OS default
>> 4) the two files are ASCII, or at least 8 bit encoded, using the
>> same encoding  (such as both UTF-8)
>> 5) the last line of each file DOES have a trailing newline sequence
> 
> Thanks all for the input!
> I have guess I have to think it through a couple times more. :)

Indeed. Note that others thinking through related problems have come up with

http://docs.python.org/library/difflib.html

Peter



From mondi at cs.unibo.it  Fri Jul 10 11:16:14 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Fri, 10 Jul 2009 15:16:14 +0000
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <mailman.2929.1247192119.8015.python-list@python.org>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
Message-ID: <h37eat$qmm$1@lec.cs.unibo.it>

Roger Binns wrote:
> jacopo mondi wrote:
>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>> add support to an experimental socket family.
> 
> You may find it considerably easier to use ctypes since that will avoid
> the need for any patching.  You'll also be able to control how read and
> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
> os.fdopen to convert your raw file descriptor into a Python file object
> if appropriate.
> 
> If you do use ctypes then you'll only need to distribute pure Python
> source code.
> 
> Roger

Wait a minute, am I confused or ctypes seems to be unusless for my needs?
Ctypes wraps a system shared object (as libc is) and gives you the
possibility to access its functions. What have I to wrap? the
fuctionalities I need to use are those exposed by the kernel via
sys/socket.h haeder (socket, bind, connect etc.).
Maybe I could wrapp _socket.so (I think it's possible) but seems to be
unuseless because I need to modify, for example, the parameters that
_socket.so passes to the socket() function in order to create a socket
owned by the new socket family I'm actualy experimenting.
Hope it's clear what I'm trying to explain...

Thanks anyway, but ctypes doen't seem to fit my needs..

cheers
	jacopo


From aahz at pythoncraft.com  Fri Jul 10 11:19:48 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 08:19:48 -0700
Subject: PyGtk Depends on Numeric
References: <1ebe9314-9434-459a-bd3e-2b2386a35f1b@n11g2000yqb.googlegroups.com>
Message-ID: <h37m6k$p37$1@panix3.panix.com>

In article <1ebe9314-9434-459a-bd3e-2b2386a35f1b at n11g2000yqb.googlegroups.com>,
dieter  <vel.accel at gmail.com> wrote:
>
>Get with the times people and port to numpy. :P
>Don't you think its about time?

Are you trying to get something to happen or just posting a random
drive-by?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From francois.dot.grondin at bpr-cso.dot.com  Fri Jul 10 11:20:48 2009
From: francois.dot.grondin at bpr-cso.dot.com (François Grondin)
Date: Fri, 10 Jul 2009 15:20:48 GMT
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
	<h36ki102d7m@news5.newsguy.com>
Message-ID: <k%I5m.34251$Db2.2196@edtnps83>


"David Bernier" <david250 at videotron.ca> a ?crit dans le message de news: 
h36ki102d7m at news5.newsguy.com...
> Musatov wrote:
>> On Jul 9, 7:54 pm, David Bernier <david... at videotron.ca> wrote:
>>> Musatov wrote:
>>>> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
>>>> its adopted use in Pakistan.  The search engine has grown in
>>>> popularity 10,000 fold following its Beta test launch three months ago
>>>> in April, 2009. Supporters of the site claim it is better than rival
>>>> Google upon which platform it is based. Controversy arose after
>>>> MeAmI.org search code allowed users to search other users Google
>>>> results with no advertising. "It is truly an innovative thing we are
>>>> doing," said Founder and CEO, Martin Musatov. "Letting users search
>>>> the results of other Google users immediately results in a level of
>>>> accuracy and relevance above and beyond Google." Google changed their
>>>> API following the launch or MeAmI.org and explored the possibility of
>>>> blocking site access from MeAmI.org to Google search results but was
>>>> unable to do so. Critics of MeAmI.org say what it is doing is
>>>> tantamount to intellectual theft. When asked about this topper Musatov
>>>> exclaimed, "The Internet was made for people, not companies." An
>>>> analyst at Goldman Sachs says, requesting to remain anonymous,
>>>> "MeAmI.org has a strong presence in promoting itself as a vehicle for
>>>> global activism and to tell you the truth, this makes it much more
>>>> likely an acquisition target than potential intellectual property
>>>> violator." Google could not be reached for comment.
>>> Mr. Musatov,  do you know who originally wrote the
>>> article above?
>>>
>>> Thank you.
>>>
>>> David Bernier- Hide quoted text -
>>>
>>> - Show quoted text -
>>
>> Yes.
>
> Mr. Musatov, do you know the name of the person who
> originally wrote the article above?
>
> Thank you.
>
> David Bernier

Maybe Mr. Musatov should answer the following questions instead :
1. Did you write the article above?
2. If not, who did? And I don't want AP as the answer, but the name of the 
journalist.

David, don't take it bad, but he answered your question with an accurate 
answer (yes), You gave him the opportunity to avoid the real answer and he 
took it. Based on Musatov's strange behavior and logic, don't expect more 
from him. Ask anyone else the same question and you'd get a real answer.

BTW, my guess for question 2 would be the Masked Logician, Floetry, 
scriber77, or Professor X.

Francois 




From aahz at pythoncraft.com  Fri Jul 10 11:23:29 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 08:23:29 -0700
Subject: language analysis to enforce code standards
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
	<pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
	<mailman.2948.1247229186.8015.python-list@python.org>
Message-ID: <h37mdh$rfm$1@panix3.panix.com>

In article <mailman.2948.1247229186.8015.python-list at python.org>,
Jean-Michel Pichavant  <jeanmichel at sequans.com> wrote:
>
>You could also verify there are at least N different characters used in 
>the sentence:
>
>N = 5 # must contains at least 5 different characters
>record = []
>for c in s:
>    if c not in record:
>        record += [c]
>if len(record) >= N:
>    print "at least %s different characters" % N

Much simpler and *way* more efficient with a set:

if len(set(s)) < N:
    print "Must have at least %s different characters" % N
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From Scott.Daniels at Acm.Org  Fri Jul 10 11:28:29 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 08:28:29 -0700
Subject: tough-to-explain Python
In-Reply-To: <007318de$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>

Steven D'Aprano wrote:
> Even *soup stock* fits the same profile as what Hendrik claims is almost 
> unique to programming. On its own, soup stock is totally useless. But you 
> make it, now, so you can you feed it into something else later on.
> 
> Or instant coffee.

I think I'll avoid coming to your house for a cup of coffee. :-)

--Scott David Daniels
Scott.Daniels at Acm.Org


From magobin at gmail.com  Fri Jul 10 11:33:18 2009
From: magobin at gmail.com (Alex)
Date: Fri, 10 Jul 2009 08:33:18 -0700 (PDT)
Subject: problem with keys combination!
Message-ID: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>

Hi at all,
  I made a simple program that make a screenshot of Desktop and use it
as fullscreen background and then a ball erase image making illusion
that erase Desktop. The program working fine and I succesfully blocked
all keys but I have a problem with hotkey combination Ctrl-Alt-
Del...that bypass my FullScreen Application. Reading in google I
understood that if I want disable this keys I have to operate in more
low level. But I'm a newbe and I don't know how to make it(operate
with api is very hard 4 me).I tried several days to find a workaround
like replace one of that keys but doesn't work :-((
Plus..I can't install pyHook because there isn't a 2.6 version :-((
Can someone help me ??
thanks in advance
Alex

This is a piece of my code:
while True:
    pg.event.pump()
    keyinput = pg.key.get_pressed()
    # press ESC to exit
    if keyinput[pg.K_ESCAPE]
            raise SystemExit
    if  keyinput[pygame.K_LALT] and keyinput[pygame.K_LCTRL] and
keyinput[pygame.K_DELETE]:
         win32api.keybd_event(win32con.VK_ESCAPE,0)
         #shell = win32com.client.Dispatch("WScript.Shell")
        #shell.SendKeys("{ESC}")
    #ignore keyboard input
    def IgnoreKeyboardInterrupt():
        return signal.signal(signal.SIGINT,signal.SIG_IGN)


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 11:48:47 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 15:48:47 GMT
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>
Message-ID: <00733dd0$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 08:28:29 -0700, Scott David Daniels wrote:

> Steven D'Aprano wrote:
>> Even *soup stock* fits the same profile as what Hendrik claims is
>> almost unique to programming. On its own, soup stock is totally
>> useless. But you make it, now, so you can you feed it into something
>> else later on.
>> 
>> Or instant coffee.
> 
> I think I'll avoid coming to your house for a cup of coffee. :-)


I meant the instant coffee powder is prepared in advance. It's useless on 
it's own, but later on you feed it into boiling water, add sugar and 
milk, and it's slightly less useless.



-- 
Steven


From davea at ieee.org  Fri Jul 10 11:57:21 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 11:57:21 -0400
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100718p5e48506cg2d133842972d6328@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>	
	<4A57486E.9070900@ieee.org>
	<3d4ff96c0907100718p5e48506cg2d133842972d6328@mail.gmail.com>
Message-ID: <4A5764E1.7010102@ieee.org>

jhinak sen wrote:
> hey,
> thanx a lot :)
> i got ur points .. and it really helps..
>
> and please also tell me ...
> where i can get more basic and detail knowledge of python.. as i am
> beginners in this , i need more examples  of python programmes so that i can
> understand better.
> also if you know of any gud pdf file or book please let me know
>
> thnx a lot
> jhinak
>
> On Fri, Jul 10, 2009 at 7:25 PM, Dave Angel <davea at ieee.org> wrote:
>
>   
>> jhinak sen wrote:
>>
>>     
>>> hi,
>>> i am a beginner in python language,
>>>
>>> i am trying with this programme :
>>> to find the addition and mean from a data set in a file and writing the
>>> mean
>>> and sum in some other file :
>>> ""
>>> *#! /usr/bin/env python
>>>
>>> import re
>>> import cPickle as p
>>> import math
>>> from numpy import *
>>>
>>> f0= open("temp9","r+").readlines()
>>> f2= open("out1","r+")
>>> add_1=[ ];
>>> for i in range(0, len(f0)):
>>>        f1=f0[i].split()
>>>        add= float(f1[1])+float(f1[2])
>>>    mean= float(add)/2
>>>        print (f1[1]).ljust(6) ,(f1[2]).ljust(6),repr(add).ljust(7),
>>> repr(mean).ljust(7)
>>>        add_1.append(add)
>>>    add_1.append(mean)
>>>        f2.write("%s" % repr(add).ljust(7)),f2.write("%s" %
>>> repr(mean).ljust(7))
>>> print "printing from file"
>>> for i in range(0, len(add_1),2):
>>>        print add_1[i],"        ", add_1[i+1]
>>>
>>> f0.close()
>>> f2.close()*
>>>
>>>
>>> ""
>>>
>>> and this programme is givving me this error :
>>>
>>> ""    *Traceback (most recent call last):
>>>  File "./temporary1.py", line 24, in <module>
>>>    f0.close()
>>> AttributeError: 'list' object has no attribute 'close'*
>>> ""
>>>
>>> please help to to find the error.
>>> or suggest some simpler or better way
>>>
>>> note:
>>> 1)file "temp9" is already exist
>>> 2)this programme is giving me all my outputs, but at the end of the out
>>> ..its giving me that error.
>>>
>>>
>>>
>>>       
>> Others have pointed out the specific problem that gives you this error.
>>  But I'd like to point out a few other things to consider:
>>
>> 1) Don't mix tabs and spaces.  Best practice is to bind tab to (4) spaces
>> in your editor, and never have a tab in a Python source file.
>> 2) Think about your variable names.  As it stands, f0 is a list of lines,
>> f1 is a list of "word" within a line, and f2 is a file.  No wonder you
>> accidentally tried to close the list.  I'd suggest things like:
>>     infile = open(....)
>>     lines = infile.readlines()
>>     outfile = open(....)
>>
>>     for line in lines:
>>            words = line.split(" ")     or  even   val1, val2 =
>> lines.split(" ")
>>
>>  Then of course the last two lines become
>>  infile.close()
>>  outfile.close()
>>
>> 3) Learn to use the for statement directly on a list, rather than using
>> len() on the list to make an index, then using the index to find the value
>> 4) On the open() calls, get your modes right.  Looks like you really want
>>  infile = open(infilename, "r")
>>  outfile = open(outfilename, "w")
>> 5) Consider using tuples in your add_1 list, rather than separate elements.
>>  That way, each element of the list would contain both sum and mean.
>>              add_1.append((add, mean))
>>
>>      and the final print would become
>>
>>   for item in add_1:
>>       print item[0],"        ", item[1]
>>
>> 6) Put anything over three lines into a function, instead of doing it at
>> module scope.  That way, you'll be clearer about what things are local to
>> this code, and what might be useful to other code in the same module.
>> In this case,  infilename, and outfilename might be arguments to that
>> function.
>>
>> There are lots of other refinements, but these are all within your reach,
>> and would make the program much clearer.
>>
>>
>>     
>
>   
Please don' t top-post.  Putting your reply out of order makes it harder 
for others to see the sequences of things.  Some people top-post 
everything, but on this mailing list (and maybe most), the standard is 
to add to bottom, or inline where appropriate.

Anyway,
http://docs.python.org/tutorial/
http://diveintopython.org/
http://www.openbookproject.net/thinkCSpy/

are all good, depending on your experience with other languages, and 
with your computer's OS.

You could also check out
http://code.activestate.com/recipes/     or    
http://code.activestate.com/recipes/langs/python/  for Python specifically

which has a large set of relatively small modules of code.
For a examples that might stretch your thought process:
    http://code.activestate.com/recipes/576755/
    http://code.activestate.com/recipes/576647/




From darcy at druid.net  Fri Jul 10 12:09:28 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Fri, 10 Jul 2009 12:09:28 -0400
Subject: tough-to-explain Python
In-Reply-To: <00733dd0$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>
	<00733dd0$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <20090710120928.075451c8.darcy@druid.net>

On 10 Jul 2009 15:48:47 GMT
Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
> I meant the instant coffee powder is prepared in advance. It's useless on 
> it's own, but later on you feed it into boiling water, add sugar and 
> milk, and it's slightly less useless.

I don't know about that.  I find instant coffee pretty useless no
matter what it is fed to.  :-)

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From bryanvick at gmail.com  Fri Jul 10 12:13:41 2009
From: bryanvick at gmail.com (Bryan)
Date: Fri, 10 Jul 2009 09:13:41 -0700 (PDT)
Subject: Automate rsync w/ authentication
Message-ID: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>

I am trying to automate rsync to backup server A from server B.  I
have set up a private/public key between the two servers so I don't
have to enter a password when using rsync.  Running rsync manually
with the following command works fine:
rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp

But when I try to do it with python, the subprocess simply returns the
ssh -h output on stderr like I am passing some invalid syntax.  What
is wrong in my translation of rsync's -e command from shell to
pythyon?

#! /usr/bin/python
from subprocess import Popen, PIPE
rsyncExec = '/usr/bin/ssh'
source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
dest = '/home/bry/tmp'
rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
try:
	p = Popen(args, stdout=PIPE, stderr=PIPE)
	print 'rsync running with pid %s' % p.pid
	out, err = p.communicate()
	print 'Errors: %s' % err
	print 'Output: %s' % out
except Exception:
	print 'Error running rsync'



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 12:14:04 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 16:14:04 GMT
Subject: problem with keys combination!
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
Message-ID: <007343bd$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 08:33:18 -0700, Alex wrote:

> Hi at all,
>   I made a simple program that make a screenshot of Desktop and use it
> as fullscreen background and then a ball erase image making illusion
> that erase Desktop. The program working fine and I succesfully blocked
> all keys but I have a problem with hotkey combination Ctrl-Alt-
> Del...that bypass my FullScreen Application.


What operating system are you using? Windows?

As I understand it, you can't block, modify, or otherwise access Ctrl-Alt-
Del while running under Windows: it is the "Secure Attention Key", and is 
designed to be virtually impossible to interfere with. It's not *quite* 
impossible, but it is the deepest, darkest black magic. Microsoft makes 
it close enough to impossible as makes no difference even for experienced 
developers.

As a newbie, well, put it this way: it's like somebody saying "Hi guys, I 
have a shiny new Swiss Army Knife, the one with the screwdriver and the 
corkscrew. I'd like to build my own Space Shuttle -- what do I do?"

http://stackoverflow.com/questions/886076/how-can-i-intercept-all-key-events-including-ctrlaltdel-and-ctrltab

http://en.wikipedia.org/wiki/Control-Alt-Delete

You should also read this:

http://blogs.msdn.com/oldnewthing/archive/2004/02/16/73780.aspx



-- 
Steven


From mal at egenix.com  Fri Jul 10 12:15:31 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Fri, 10 Jul 2009 18:15:31 +0200
Subject: DBI module deprecated at Python 2.5--what to use in its place?
In-Reply-To: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
Message-ID: <4A576923.6050507@egenix.com>

dana wrote:
> I have a variety of Python 2.4 scripts that utilitize the DBI and ODBC
> modules together. Although I don't have Python 2.5, I've been informed
> the DBI module has been deprecated at 2.5. A few questions:
> 
> 1) Although deprecated, will it work at all in 2.5? Does the fact that
> it is deprecrated mean it has been removed entirely, or does Python
> 2.5 simply issuing a warning?
> 
> 2) What do I use in place of DBI for my Python 2.4. scripts that
> import modules DBI and ODBC together. I don't use DBI directly. It was
> simply a dependency for the ODBC module as best I knew.

If you're looking for a stable and maintained ODBC for Python,
have a look at our mxODBC extension or mxODBC Connect package:

http://www.egenix.com/products/python/mxODBC/
http://www.egenix.com/products/python/mxODBCConnect/

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 10 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 10 12:17:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 10 Jul 2009 16:17:09 GMT
Subject: help me to find the error
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
	<4A57486E.9070900@ieee.org>
	<3d4ff96c0907100718p5e48506cg2d133842972d6328@mail.gmail.com>
	<mailman.2958.1247241458.8015.python-list@python.org>
Message-ID: <00734476$0$9710$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 11:57:21 -0400, Dave Angel wrote:

[...]
> Please don' t top-post.  Putting your reply out of order makes it harder
> for others to see the sequences of things.  Some people top-post
> everything, but on this mailing list (and maybe most), the standard is
> to add to bottom, or inline where appropriate.

Inline is nearly always appropriate. Please trim your replies, leaving 
only what you need for context and what you are replying to directly, not 
the entire every-growing collection of quoted-quoted-quoted-quoted-quotes.

Thank you.


-- 
Steven


From mal at egenix.com  Fri Jul 10 12:18:28 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Fri, 10 Jul 2009 18:18:28 +0200
Subject: Remoting over SSH
In-Reply-To: <4A549B07.2090402@gmail.com>
References: <e0f8b2cd-fd2f-4de8-be04-5bb0071b2c18@o6g2000yqj.googlegroups.com>
	<4A549B07.2090402@gmail.com>
Message-ID: <4A5769D4.8080106@egenix.com>

Lucas Carvalho wrote:
> Hussein B wrote:
>> Hey,
>> I want to perform commands on a remote server over SSH.
>> What do I need?
>> Thanks.
>>   
> Hi,
> If you want to use the SSH2 protocol into a python code, you should
> take a look at this module: paramiko [1].
> 
> [1] http://www.lag.net/paramiko/

If you're looking for remote Python execution over SSH have
a look at http://codespeak.net/py/dist/execnet.html

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 10 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From pdpinheiro at gmail.com  Fri Jul 10 12:23:55 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Fri, 10 Jul 2009 09:23:55 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org> 
	<007318de$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <c40ec96a-5494-483c-a461-676c8bb29876@x3g2000yqa.googlegroups.com>

On Jul 10, 2:11?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Fri, 10 Jul 2009 12:54:21 +0200, Hendrik van Rooyen wrote:
> > "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
>
> >>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>
> >>>> persistent idea "out there" that programming is a very accessible
> >>>> skill, like cooking or gardening, anyone can do it, and even profit
> >>>> from it, monetarily or otherwise, etc., and to some extent I am
>
> >>> Programming is not like any other human activity.
>
> >>In practice? In principle? Programming in principle is not the same as
> >>it is performed in practice.
>
> >>But in either case, programming requires both the logical reasoning of
> >>mathematics and the creativity of the arts. Funnily enough,
>
> > I do not buy this arty creativity stuff. - or are you talking about
> > making a website look pretty?
>
> I must admit, it never crossed my mind that anyone here would claim that
> there was no creativity involved in programming, that it was all a
> mindless, algorithmic process capable of being done by a simple
> mechanical device.
>
> This is certainly the accusation made against *bad* programmers -- that
> they can't actually solve new, unique problems, but just apply recipes
> they learned without any insight or intelligence. The sort of people who
> program so poorly that "a trained monkey could do what they do".

I wholeheartedly agree. Coming up with Duff's device is nothing if not
creative. My mind still reels at trying to grok it.
http://www.lysator.liu.se/c/duffs-device.html

> Even *soup stock* fits the same profile as what Hendrik claims is almost
> unique to programming. On its own, soup stock is totally useless. But you
> make it, now, so you can you feed it into something else later on.
>
> Or instant coffee.

I've always found cooking an apt metaphor for programming.

You've got your well-limited for loops (cook for x minutes), your less
straightforward while/until loops (roast until golden), you have your
subprocedures (prepare sauce in advance/in parallel), you have some
conditionals (tenderize the steak if the meat isn't really that
tender), etc etc.

The complexities of assignment can be easily visualized in terms of
containers and mixing stuff together. Nothing makes a += b more
obvious than having a bowl of cream (a), an egg (b), and adding the
egg to the bowl of cream (a += b). Well, except for the part where
that in that case evaluating b is destructive ;)

> They can't reason? Then what are they doing when they manipulate symbols?

"Computers aren't intelligent. They only think they are." Or, more to
the point: the typical definition of "reasoning" tends to involve more
of what defines humans as self-aware, animate beings than what is
usually ascribed to computers.


From charles at declareSub.com  Fri Jul 10 12:27:25 2009
From: charles at declareSub.com (Charles Yeomans)
Date: Fri, 10 Jul 2009 12:27:25 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <DCF5052E-509C-47EF-B7BD-E942B739D6C7@declareSub.com>


On Jul 9, 2009, at 10:57 PM, Steven D'Aprano wrote:

> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
>
>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>>
>>> Nobody says you shouldn't check your data. Only that "assert" is not
>>> the right way to do that.
>>
>> "assert" is not the right way to check your *inputs*. It's a  
>> perfectly
>> reasonable way to check data which "should" be valid, as well as a  
>> way
>> to document what variables are supposed to contain.
>
> Where are those variables coming from?
>
> The distinction really boils down to this:
>
> * asserts should never fail. If there is any chance that an assertion
> might fail outside of test suites, then don't use assert.
>
>
> You can't control what input the caller provides to a function, so  
> unless
> the data is generated inside the function, a caller might provide
> something unexpected. Therefore, assert is inappropriate for checking
> function parameters, even if that function is "private" and only  
> called
> by your own functions.
>
> (1) So-called "private" or "internal" functions have a habit of  
> becoming
> public, and then you have asserts in public functions.
>
> (2) If public() calls _private(x), and _private uses assert to check  
> the
> value of x, there is a risk that if public() is buggy and supplies an
> invalid x, the assertion will never be checked and _private() will  
> return
> incorrect results.
>
> (3) assert is absolutely unsuitable for enforcing pre-conditions and  
> post-
> conditions, unless such conditions are mere "guidelines", because  
> assert
> can be switched off at runtime.


Unless, of course, you want to switch off such checking at runtime, as  
you might when using a design-by-contract approach.

Charles Yeomans


From aahz at pythoncraft.com  Fri Jul 10 12:33:06 2009
From: aahz at pythoncraft.com (Aahz)
Date: Fri, 10 Jul 2009 09:33:06 -0700
Subject: BayPIGgies at OSCON: 7/23 8-9:30pm
Message-ID: <20090710163306.GA10586@panix.com>

NOTE: time change AND location change

The July BayPIGgies meeting will be held at OSCON in the San Jose
Convention Center as one of the BoF (Birds of a Feather) sessions from
8pm to 9:30pm Thursday July 23.  Everyone is welcome: you do NOT need to
be an OSCON member to attend a BoF.

Wesley Chun will have a newbie-oriented "What is Python?" BoF from 7-8pm
in the same room as BayPIGgies (we don't know which room yet).

The July meeting is supposed to have a Django focus, but the program
hasn't been settled yet, either.

For more information, see
http://baypiggies.net/

Discussion of details will take place on the BayPIGgies list:
http://mail.python.org/mailman/listinfo/baypiggies
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From gabrielmonnerat at gmail.com  Fri Jul 10 12:36:22 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Fri, 10 Jul 2009 13:36:22 -0300
Subject: problem with subprocess
Message-ID: <4A576E06.5080006@gmail.com>

Hi all,

I need start a openoffice in Xvfb, but when I call with the DISPLAY 
occurs this error:

[root at localhost oood]# Xvfb :99 -screen 0 1024x768x24 &
 
In [9]: subprocess.call('/opt/ooo-dev3/program/soffice.bin')
Out[9]: 0

In [10]: subprocess.call('DISPLAY=:99 /opt/ooo-dev3/program/soffice.bin')
---------------------------------------------------------------------------
OSError                                   Traceback (most recent call last)

/home/gabriel/<ipython console> in <module>()

/usr/lib/python2.6/subprocess.pyc in call(*popenargs, **kwargs)
    442     retcode = call(["ls", "-l"])
    443     """
--> 444     return Popen(*popenargs, **kwargs).wait()
    445
    446

/usr/lib/python2.6/subprocess.pyc in __init__(self, args, bufsize, 
executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, 
env, universal_newlines, startupinfo, creationflags)
    593                             p2cread, p2cwrite,
    594                             c2pread, c2pwrite,
--> 595                             errread, errwrite)
    596
    597         # On Windows, you cannot just redirect one or two 
handles: You


/usr/lib/python2.6/subprocess.pyc in _execute_child(self, args, 
executable, preexec_fn, close_fds, cwd, env, universal_newlines, 
startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, 
errread, errwrite)
   1104                 os.waitpid(self.pid, 0)
   1105                 child_exception = pickle.loads(data)
-> 1106                 raise child_exception
   1107
   1108

OSError: [Errno 2] No such file or directory

I am using subprocess because I need store the pid. Any suggestions?

thanks in advance,

Gabriel M. Monnerat



From inky788 at gmail.com  Fri Jul 10 12:44:34 2009
From: inky788 at gmail.com (Inky 788)
Date: Fri, 10 Jul 2009 09:44:34 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com> 
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net> 
	<mailman.2759.1246954003.8015.python-list@python.org>
	<59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
	<mailman.2953.1247235967.8015.python-list@python.org>
Message-ID: <cb69063d-44a2-4706-9efc-90b3bda480f8@f33g2000vbm.googlegroups.com>

On Jul 10, 10:26?am, Chris Withers <ch... at simplistix.co.uk> wrote:
> Inky 788 wrote:
> > Currently, distutils itself is being actively developed. More info
> > about this here:http://tarekziade.wordpress.com/
>
> > My (albeit anonymous) advice is: use distutils. Manually download
> > packages as-needed from PyPI and install manually using standard
> > distutils.
>
> No thanks. I'm a big fan of buildout. Making it possible for packages to
> specify their dependencies is a big win...

Yup, it's a big win. But package installation for Python is a bit of a
mess right now. Neither setuptools nor buildout (nor pip for that
matter) are a standard part of Python. It's rather silly that although
Python is a batteries-included language, and it's mid-2009, and Python
3.1 has been released, that Python *still* doesn't have a standard
built-in way to handle package installation (including dependencies
and uninstallation).

My guess is that once distutils finishes getting spruced up, some
intrepid hacker is going to:

* take the best parts of pip and the best parts of setuptools (I don't
know anything about buildout),

* stir vigorously,

* ruthlessly remove the excess pieces,

* write good documentation for it,

* throw the result up on github/launchpad/bitbucket/whatever,

and then *that's* what everyone's going to start using and which will
eventually make it into the Python std lib.

But that's just my anon 2 cents.


From psimon at sonic.net  Fri Jul 10 12:47:42 2009
From: psimon at sonic.net (Paul Simon)
Date: Fri, 10 Jul 2009 09:47:42 -0700
Subject: tkinter problem
References: <4a55292f$0$95538$742ec2ed@news.sonic.net>
	<mailman.2863.1247095339.8015.python-list@python.org>
	<4a5536d4$0$95520$742ec2ed@news.sonic.net>
	<h3481q$d95$00$1@news.t-online.com>
	<4a5615ba$0$95523$742ec2ed@news.sonic.net>
	<h35f78$pts$1@ruby.cit.cornell.edu>
Message-ID: <4a5770bc$0$95549$742ec2ed@news.sonic.net>


"David Smith" <dns4 at cornell.edu> wrote in message 
news:h35f78$pts$1 at ruby.cit.cornell.edu...
> Paul Simon wrote:
>> "Peter Otten" <__peter__ at web.de> wrote in message
>> news:h3481q$d95$00$1 at news.t-online.com...
>>> Paul Simon wrote:
>>>
>>>> "Chris Rebert" <clp2 at rebertia.com> wrote in message
>>>> news:mailman.2863.1247095339.8015.python-list at python.org...
>>>> On Wed, Jul 8, 2009 at 4:18 PM, Paul Simon<psimon at sonic.net> wrote:
>>>>> I have the "tkinter" problem and need some assistance to straighten it
>>>>> out.
>>>>> >From the web page "http://wiki.python.org/moin/TkInter" I tested as 
>>>>> >in
>>>>>> "step
>>>>> 1" and cannot import "_tkinter." I do not have that file on my 
>>>>> computer,
>>>>> but
>>>>> do have tkinter.py in /usr/local/lib/python2.6/lib-tk. as well as the
>>>>> directories /usr/lib/tk8.5 and /usr/lib/tcl8.5.
>>>>> This python stuff is great, but the documentation frequently
>>>>> feels like it is just a bit out of my grasp. I realize that all of 
>>>>> this
>>>>> is free but I understand the instructions on the web page to repair 
>>>>> only
>>>>> to the
>>>>> point of confusion. I'm not an expert. How do I modify my python
>>>>> configuration? Is there a file that needs to be edited? Which setup.py
>>>>> file
>>>>> do I use? Make? or python setup.py build and python setup.py install?
>>>>> Thanks. I appreciate your help.
>>>> - How did you install Python?
>>>> - What Linux distro are you using?
>>>>
>>>> Cheers,
>>>> Chris
>>>> http://blog.rebertia.com
>>>> I"m using Mandriva 2008.1.  I have to tell you honestly that I'm not 
>>>> sure
>>>> exactly how I installed Python.  Originally I had installed 2.5 from 
>>>> RPM
>>>> but 2.6 was not available for my distro (2008.1) in RPM.  I downloaded
>>>> something from python.org and installed.  Not sure if it was tarball or
>>>> zip file.
>>> Zip or tar doesn't matter, you are installing "from source".
>>>
>>> Python has to find the necessary include files for tcl/tk. These are in
>>> separate packages that you have to install before you invoke Python's
>>> configure script.
>>>
>>> I don't know what they are called on your system -- look for tk-dev.rpm,
>>> tcl-dev.rpm or similar.
>>>
>>> You may run into the same problem with other modules like readline.
>>>
>>> Peter
>>>
>>
>> Thank you Peter.  I understand what you are saying but don't know how to 
>> do
>> it.  Although I installed from source, I followed a "cookbook" recipe.
>> Could you tell me what files to execute, where they might be, and file
>> arguments?  I'm just ignorant, not stupid. ;-).
>>
>> Paul
>>
>>
>
> Just install the tkinter package from the Mandriva Linux Control
> Center's Software Management system.  I just did it, doing a search for
> tkinter brought it right up.  All done.
>
> --David

Thanks to all for your patient help.  I have made some progress, but still 
no success.  I installed Active Tcl-8.5.7 and corrected the PATH 
accordingly.  However I still get a "missing" message on building Python. 
"Failed to find the necessary bits (!) to build these modules:

....
_tkinter (among others)
To find the necessary bits, look in setup.py in detect_modules() for teh 
module's name."

Not sure what bits are, euphemism?  but am about to wipe the disk and 
reinstall linux, etc.

Paul 




From gabrielmonnerat at gmail.com  Fri Jul 10 12:48:50 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Fri, 10 Jul 2009 13:48:50 -0300
Subject: problem with subprocess
In-Reply-To: <4A576E06.5080006@gmail.com>
References: <4A576E06.5080006@gmail.com>
Message-ID: <4A5770F2.7050308@gmail.com>

gabrielmonnerat wrote:
> Hi all,
>
> I need start a openoffice in Xvfb, but when I call with the DISPLAY 
> occurs this error:
>
> [root at localhost oood]# Xvfb :99 -screen 0 1024x768x24 &
>
> In [9]: subprocess.call('/opt/ooo-dev3/program/soffice.bin')
> Out[9]: 0
>
> In [10]: subprocess.call('DISPLAY=:99 /opt/ooo-dev3/program/soffice.bin')
> --------------------------------------------------------------------------- 
>
> OSError                                   Traceback (most recent call 
> last)
>
> /home/gabriel/<ipython console> in <module>()
>
> /usr/lib/python2.6/subprocess.pyc in call(*popenargs, **kwargs)
>    442     retcode = call(["ls", "-l"])
>    443     """
> --> 444     return Popen(*popenargs, **kwargs).wait()
>    445
>    446
>
> /usr/lib/python2.6/subprocess.pyc in __init__(self, args, bufsize, 
> executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, 
> env, universal_newlines, startupinfo, creationflags)
>    593                             p2cread, p2cwrite,
>    594                             c2pread, c2pwrite,
> --> 595                             errread, errwrite)
>    596
>    597         # On Windows, you cannot just redirect one or two 
> handles: You
>
>
> /usr/lib/python2.6/subprocess.pyc in _execute_child(self, args, 
> executable, preexec_fn, close_fds, cwd, env, universal_newlines, 
> startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, 
> c2pwrite, errread, errwrite)
>   1104                 os.waitpid(self.pid, 0)
>   1105                 child_exception = pickle.loads(data)
> -> 1106                 raise child_exception
>   1107
>   1108
>
> OSError: [Errno 2] No such file or directory
>
> I am using subprocess because I need store the pid. Any suggestions?
Sorry, I was forgot the parameter shell=True.
i.e
In [20]: subprocess.call('DISPLAY=:99 
/opt/ooo-dev3/program/soffice.bin',shell=True)

lack of attention mine
>
> thanks in advance,
>
> Gabriel M. Monnerat
>
>
Gabriel M. Monnerat


From jcd at sdf.lonestar.org  Fri Jul 10 12:50:27 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 12:50:27 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <1247244628.8029.15.camel@aalcdl07>

On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
> 
> > On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
> > 
> >> Nobody says you shouldn't check your data. Only that "assert" is not
> >> the right way to do that.
> > 
> > "assert" is not the right way to check your *inputs*. It's a perfectly
> > reasonable way to check data which "should" be valid, as well as a way
> > to document what variables are supposed to contain.
> 
> Where are those variables coming from?
> 
> The distinction really boils down to this:
> 
> * asserts should never fail. If there is any chance that an assertion 
> might fail outside of test suites, then don't use assert.
> 

I'm no expert, but the more I read this thread, and the more I think on
it, the more I believe that asserts don't really need to exist outside
of test suites.  The function that assertions provide is handled in a
far more robust and maintainable way by unit tests and doctests.
Anything else should be handled by more descriptive exceptions.  

The use of assertions in regular code may just be a historical baby step
on the way to real code testing.

To play devils advocate for a moment, one possible use case for assert
statements is if you need to test something that you can't easily get
under a proper unittest or doctest.  Maybe you need to know the value of
a variable halfway through a method.  A judicious assertion can help
supplement your test suite  A better solution would be to refactor so
you can get the needed value under test, but if time constraints won't
allow it, then make your assertion and move on, but only to help you
debug the code, not to protect your code at runtime.  Even then, why not
use a proper Exception (unless speed is a major issue)?

Even if it is only used internally in a module, I would still prefer a
ValueError to an AssertionError.  It tells you what's happening more
clearly.  And it protects you if another caller (even one internal to
the class) calls it with a different set of assumptions.

At minimum, I think there's a heavy burden on an author to justify the
use of AssertionErrors rather than other kinds of Exceptions. 

Cheers,
Cliff



From magobin at gmail.com  Fri Jul 10 12:52:47 2009
From: magobin at gmail.com (Alex)
Date: Fri, 10 Jul 2009 09:52:47 -0700 (PDT)
Subject: problem with keys combination!
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
	<007343bd$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <03eeae5c-fe58-41d1-91ea-f3e5dba602dc@h11g2000yqb.googlegroups.com>

Hi Steven,

> As I understand it, you can't block, modify, or otherwise access Ctrl-Alt-
> Del while running under Windows: it is the "Secure Attention Key", and is
> designed to be virtually impossible to interfere with. It's not *quite*
> impossible, but it is the deepest, darkest black magic. Microsoft makes
> it close enough to impossible as makes no difference even for experienced
> developers.

No, is possible but for my level is quite impossible:

http://www.codeproject.com/KB/winsdk/AntonioWinLock.aspx

...in this article the author move a lot a functions in a dll  and
make a demonstration with a VB and C code to use it...plus...there is
his program that make it :-))))
I thought that python can read dll via ctypes...but it's very hard for
me :-((

>
> As a newbie, well, put it this way: it's like somebody saying "Hi guys, I
> have a shiny new Swiss Army Knife, the one with the screwdriver and the
> corkscrew. I'd like to build my own Space Shuttle -- what do I do?"
>
:-))))))))))....but yes We caaaaannnnnnn

Alex


From robert.kern at gmail.com  Fri Jul 10 12:57:16 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 10 Jul 2009 11:57:16 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <1247244628.8029.15.camel@aalcdl07>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>	<pan.2009.07.10.02.28.04.344000@nowhere.com>	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<1247244628.8029.15.camel@aalcdl07>
Message-ID: <h37rtd$etd$1@ger.gmane.org>

On 2009-07-10 11:50, J. Cliff Dyer wrote:
> On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
>> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
>>
>>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>>>
>>>> Nobody says you shouldn't check your data. Only that "assert" is not
>>>> the right way to do that.
>>> "assert" is not the right way to check your *inputs*. It's a perfectly
>>> reasonable way to check data which "should" be valid, as well as a way
>>> to document what variables are supposed to contain.
>> Where are those variables coming from?
>>
>> The distinction really boils down to this:
>>
>> * asserts should never fail. If there is any chance that an assertion
>> might fail outside of test suites, then don't use assert.
>>
>
> I'm no expert, but the more I read this thread, and the more I think on
> it, the more I believe that asserts don't really need to exist outside
> of test suites.

Actually, there is a good argument that one shouldn't use an assert statement in 
test suites: code can have bugs that only show up under -O so you want to be 
able to run your test suite under -O.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From inky788 at gmail.com  Fri Jul 10 12:57:46 2009
From: inky788 at gmail.com (Inky 788)
Date: Fri, 10 Jul 2009 09:57:46 -0700 (PDT)
Subject: Where does setuptools live?
References: <a6dd8086-b106-4734-8d6f-a2a88240b6a6@o6g2000yqj.googlegroups.com>
	<3f8cc929-557d-49ca-990e-69809f134171@t21g2000yqi.googlegroups.com> 
	<4A52A055.8080108@simplistix.co.uk>
	<d7a4b1f129accf47d72f18aec329aea8@preisshare.net> 
	<mailman.2759.1246954003.8015.python-list@python.org>
	<59968eb0-bfbb-4f38-aa72-26438e5bd6cd@h18g2000yqj.googlegroups.com>
	<mailman.2953.1247235967.8015.python-list@python.org>
Message-ID: <d29a71b6-6b3c-4b42-a054-4327dbd7552a@g23g2000vbr.googlegroups.com>

On Jul 10, 10:26?am, Chris Withers <ch... at simplistix.co.uk> wrote:
> Inky 788 wrote:
> > Currently, distutils itself is being actively developed. More info
> > about this here:http://tarekziade.wordpress.com/
>
> > My (albeit anonymous) advice is: use distutils. Manually download
> > packages as-needed from PyPI and install manually using standard
> > distutils.
>
> No thanks. I'm a big fan of buildout. Making it possible for packages to
> specify their dependencies is a big win...

Read this: http://tarekziade.wordpress.com/2009/07/03/dropping-pep-386-versions-comparison/

So, again, I don't know anything about buildout, and it might be a
nice interim solution, but there are some new and exciting
developments in distutils coming down the pike, and whatever becomes
the standard Python package management system will very likely be
based on those new developments.

I just hope it all happens sooner than later. :)


From manuel.graune at koeln.de  Fri Jul 10 13:00:11 2009
From: manuel.graune at koeln.de (Manuel Graune)
Date: Fri, 10 Jul 2009 19:00:11 +0200
Subject: Nested Classes and Instances
Message-ID: <m3r5woh3s4.fsf@uriel.graune.org>


Hello,

as an example of what I would like to achieve, think of a street
where each house has a door and a sign with a unique (per house)
number on it. I tried to model this like this:

class House(object):
    class Door(object):
        def __init__(self,color):
             self.color=color
    class Sign(object):
        def __init__(self,text):
             self.text=text
    def __init__(self, doorcolor,housenumber):
        self.housenumber=housenumber
        self.door=House.Door(doorcolor)
        self.sign=House.Sign(housenumber)

house1=House("red","1")
house2=House("blue","2")

Well, so far, so good. Now, what I'd like to achive is that the text of
the "sign" changes whenever the variable "housenumber" of the
"parent-instance" changes or  that
"house1.sign.text" is a reference/pointer to "house1.housenumber"

Thanks in advance,

Manuel



-- 
A hundred men did the rational thing. The sum of those rational choices was
called panic. Neal Stephenson -- System of the world
http://www.graune.org/GnuPG_pubkey.asc
Key fingerprint = 1E44 9CBD DEE4 9E07 5E0A  5828 5476 7E92 2DB4 3C99


From lists at cheimes.de  Fri Jul 10 13:21:43 2009
From: lists at cheimes.de (Christian Heimes)
Date: Fri, 10 Jul 2009 19:21:43 +0200
Subject: problem with subprocess
In-Reply-To: <4A5770F2.7050308@gmail.com>
References: <4A576E06.5080006@gmail.com> <4A5770F2.7050308@gmail.com>
Message-ID: <h37tb7$j33$1@ger.gmane.org>

gabrielmonnerat wrote:
>> I am using subprocess because I need store the pid. Any suggestions?
> Sorry, I was forgot the parameter shell=True.
> i.e
> In [20]: subprocess.call('DISPLAY=:99
> /opt/ooo-dev3/program/soffice.bin',shell=True)

You should avoid using the shell=True parameter. It may result in
security issues and it consumes more resources. Try this:

env = os.environ.copy()
env["DISPLAY"] = ":99"
subprocess.call(['opt/ooo-dev3/program/soffice.bin', env=env)

Christian



From thudfoo at opensuse.us  Fri Jul 10 13:24:22 2009
From: thudfoo at opensuse.us (member thudfoo)
Date: Fri, 10 Jul 2009 10:24:22 -0700
Subject: can i write a assemly language programs in python
In-Reply-To: <4A573627.8090308@tim.thechases.com>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>
	<4A573627.8090308@tim.thechases.com>
Message-ID: <3d881a310907101024o7c03448cyc45103d54e7cc4ef@mail.gmail.com>

On Fri, Jul 10, 2009 at 5:37 AM, Tim Chase<python.list at tim.thechases.com> wrote:
> m.reddy prasad reddy wrote:
>>
>> can any one tell me how to write assembly language programs in python...if
>> no is there any other way to write the programs in python
>
> Bah, writing assembly language is easy in Python:
>
> ?print("MOV EAX, [EBX]")
> ?print("XOR EBX, EBX")
>
> Just adjust the strings for your favorite processor architecture and Python
> will produce the assembly code you want.
>
> Now compiling assembly to *machine* code...or calling between Python and
> assembly...that's another matter. ?But writing assembly language programs in
> Python? ?Easy. ;-)
>

"PyASM is a full-featured dynamic assembler written entirely in
Python. By dynamic, I mean that it can be used to generate and execute
machine code in python at runtime without requiring the generation of
object files and linkage. It essentially allow 'inline' assembly in
python modules on x86 platforms.

"PyASM can also generate object files (for windows) like a traditional
standalone assembler, although you're probably better off using one of
the many freely available assemblers if this is you primary goal."

http://members.verizon.net/~olsongt/usersGuide.html


From nleioatt at gmail.com  Fri Jul 10 13:26:07 2009
From: nleioatt at gmail.com (Nick)
Date: Fri, 10 Jul 2009 10:26:07 -0700 (PDT)
Subject: gett error message: "TypeError: 'int' object is not callable"
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<7xab3d9ykx.fsf@ruckus.brouhaha.com>
Message-ID: <04f36636-bf25-423e-8deb-d28d81511678@f16g2000vbf.googlegroups.com>

On Jul 9, 8:22 pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Nick <nleio... at gmail.com> writes:
> > text = file.readlines()
> > len = len(text)
> > fields = text[1].split()
>
> Is that intended to split the first line of the file?  Remember
> that arrays in python begin at index 0.

no the '1st line' is garbled meta data, but thanks man


From __peter__ at web.de  Fri Jul 10 13:37:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 10 Jul 2009 19:37:15 +0200
Subject: Nested Classes and Instances
References: <m3r5woh3s4.fsf@uriel.graune.org>
Message-ID: <h37u84$sbr$01$1@news.t-online.com>

Manuel Graune wrote:

> as an example of what I would like to achieve, think of a street
> where each house has a door and a sign with a unique (per house)
> number on it. I tried to model this like this:
> 
> class House(object):
>     class Door(object):
>         def __init__(self,color):
>              self.color=color
>     class Sign(object):
>         def __init__(self,text):
>              self.text=text
>     def __init__(self, doorcolor,housenumber):
>         self.housenumber=housenumber
>         self.door=House.Door(doorcolor)
>         self.sign=House.Sign(housenumber)
> 
> house1=House("red","1")
> house2=House("blue","2")
> 
> Well, so far, so good. Now, what I'd like to achive is that the text of
> the "sign" changes whenever the variable "housenumber" of the
> "parent-instance" changes or  that
> "house1.sign.text" is a reference/pointer to "house1.housenumber"

Python doesn't support C-style pointers, but you can work around it to some 
degree:

>>> class House(object):
...     def __init__(self, housenumber):
...             self.housenumber = housenumber
...             self.sign = Sign(self)
...
>>> class Sign(object):
...     def __init__(self, house):
...             self.house = house
...     @property
...     def text(self): return self.house.housenumber
...
>>> house = House(42)
>>> house.sign.text
42
>>> house.housenumber = "42b"
>>> house.sign.text
'42b'

If you are concerned about the tight coupling between House and Sign you can 
modify Sign to accept a function that gets the housenumber:

>>> class House(object):
...     def __init__(self, n): self.housenumber = n
...
>>> class Sign(object):
...     def __init__(self, gettext):
...             self._gettext = gettext
...     @property
...     def text(self): return self._gettext()
...
>>> house = House(7)
>>> house.sign = Sign(lambda house=house: house.housenumber)
>>> house.sign.text
7

Peter



From h at realh.co.uk  Fri Jul 10 13:43:54 2009
From: h at realh.co.uk (Tony Houghton)
Date: Fri, 10 Jul 2009 18:43:54 +0100
Subject: Running a script to build docs from setup.py
References: <20090709173343.1784710d@realh.co.uk>
	<87fxd5ny79.fsf@benfinney.id.au>
Message-ID: <20090710184354.406c26ae@realh.co.uk>

On Fri, 10 Jul 2009 11:06:34 +1000
Ben Finney <ben+python at benfinney.id.au> wrote:

> Tony Houghton <h at realh.co.uk> writes:
> 
> > I've looked through the manual but I can't find any hooks in distutils
> > for generating files at install time other than extension modules and
> > .pyc files. Should I just run the script from somewhere in my setup.py
> > before calling distutils' setup function?
> 
> Indirectly related: Ian Bicking's article on using Python's ?setup.py?
> as a ?Makefile? replacement:
> 
>     <URL:http://blog.ianbicking.org/pythons-makefile.html>

Thanks, but I don't think that adds much to the distutils manual.

> If one is writing a ?setup.py? anyway, I think it makes sense to use
> that as the build program for the whole project if possible. Good
> hunting!

Yes. Really I only want to write a setup.py because it makes it easier
to make a debian package, but the more of the installation that's done
by setup.py the better I suppose, then other people might find it
useful.

-- 
TH * http://www.realh.co.uk



From wescpy at gmail.com  Fri Jul 10 13:48:43 2009
From: wescpy at gmail.com (Wesley Chun)
Date: Fri, 10 Jul 2009 10:48:43 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
Message-ID: <89727cd5-a039-4295-8641-c5fe60e8b50f@m18g2000vbi.googlegroups.com>

On Jul 7, 1:04?pm, kj <no.em... at please.post> wrote:
> I'm having a hard time coming up with a reasonable way to explain
> certain things to programming novices.
>     :
> How do I explain to rank beginners (no programming experience at
> all) why x and y remain unchanged above, but not z?
>     :
> What do you say to that?
>
> I can come up with much mumbling about pointers and stacks and
> heaps and much hand-waving about the underlying this-and-that, but
> nothing that sounds even remotely illuminating.
>
> Your suggestions would be much appreciated!


kj,

i don't have too much to add to everyone else's response except to
describe how i deal with this. i teach Python courses several times a
year and realized long ago that conveying the concept of mutable vs.
immutable is a key to getting up-to-speed quickly with Python as well
as helping beginners.

so, although techically, this is more of an intermediate topic rather
than "beginner" material, i still teach it anyway, with the hopes of
producing better Python programmers out of the gate, and hopefully,
less frustrated ones. in fact, i dedicated an entire chapter (4) in
Core Python Programming just to address this important issue. to top
it all off, i end this module in the class by giving 2 quizzes, just
to make sure they understood what i just told them. i put the 1st one
online, so if you're curious, the PDF is at http://roadkill.com/~wesc/cyberweb/introQuiz.pdf
... the 2nd quiz is harder and involves the discussion of the
differences between shallow and deep copies. so yes, not very beginner-
ish stuff, hence the reason why i (re)named my course "Intro
+Intermediate Python".

finally, rather than the "paper tag" or alex's hotel statue analogy, i
just say that variables are like Post-It&reg; or sticky notes on
objects. i can tag objects anytime, tag objects more than once, remove
tags, or switch them to another object, etc.

just my $0.02,
-- wesley
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
"Core Python Programming", Prentice Hall, (c)2007,2001
"Python Fundamentals", Prentice Hall, (c)2009
    http://corepython.com

wesley.j.chun :: wescpy-at-gmail.com
python training and technical consulting
cyberweb.consulting : silicon valley, ca
http://cyberwebconsulting.com


From tony.lay at lmco.com  Fri Jul 10 14:03:05 2009
From: tony.lay at lmco.com (Lay, Tony)
Date: Fri, 10 Jul 2009 14:03:05 -0400
Subject: python make dies :libtk8.5.so: cannot open shared object file: No
	such file or directory
Message-ID: <71417B877DBC6946AFC52F0C1576C7D6474D7B524B@HVXMSP1.us.lmco.com>

Trying to build python-2.6.2

 

./configure --prefix=/usr/local --exec-prefix=/usr/local
LDFLAGS="-L/usr/local"

(runs through happily, had to make some libs local)

 

make runs most of the way until.

 

building '_tkinter' extension

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall
-Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I.
-I/tmp/meld/Python-2.6.2/./Include -I. -IInclude -I./Include
-I/usr/local/include -I/tmp/meld/Python-2.6.2/Include
-I/tmp/meld/Python-2.6.2 -c /tmp/meld/Python-2.6.2/Modules/_tkinter.c -o
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/_tkinter.o

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall
-Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I.
-I/tmp/meld/Python-2.6.2/./Include -I. -IInclude -I./Include
-I/usr/local/include -I/tmp/meld/Python-2.6.2/Include
-I/tmp/meld/Python-2.6.2 -c /tmp/meld/Python-2.6.2/Modules/tkappinit.c -o
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/tkappinit.o

gcc -pthread -shared
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/_tkinter.o
build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/Modules/tkappinit.o
-L/usr/X11R6/lib64 -L/usr/X11R6/lib -L/usr/local/lib -ltk8.5 -ltcl8.5 -lX11
-o build/lib.linux-i686-2.6/_tkinter.so

*** WARNING: renaming "_tkinter" since importing it failed: libtk8.5.so:
cannot open shared object file: No such file or directory

 

Failed to find the necessary bits to build these modules:

_sqlite3           bsddb185           sunaudiodev

To find the necessary bits, look in setup.py in detect_modules() for the
module's name.

 

 

Failed to build these modules:

_tkinter

 

running build_scripts

# cd /usr/local/lib

# ls -la | grep libtk8.5.so

-r-xr-xr-x   1 root root  1112606 Jul 10 13:28 libtk8.5.so

Am I missing something, it's there?

 

Regards,

 

Tony Lay

UNIX Administration 

407-306-6559

Lockheed Martin - EBS 

One Company, One Team

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/14cdbeb5/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Anthony (Tony) Lay (tony.lay at lmco.com).vcf
Type: text/x-vcard
Size: 430 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/14cdbeb5/attachment-0001.vcf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 7647 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/14cdbeb5/attachment-0001.bin>

From digitig at gmail.com  Fri Jul 10 14:29:26 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 10 Jul 2009 19:29:26 +0100
Subject: language analysis to enforce code standards
In-Reply-To: <h37dac$cfk$00$1@news.t-online.com>
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
	<h37dac$cfk$00$1@news.t-online.com>
Message-ID: <aee48b3c0907101129o7b47822agdc2f5ea6961c0e72@mail.gmail.com>

2009/7/10 Peter Otten <__peter__ at web.de>:

> Don't be a fool. Have someone other than the author read the comment.

That's the winning answer as far as I'm concerned. Automated tools are
good for picking up some types of accidental mistakes, but for
checking that comments are meaningful (and variable names, for that
matter) you can't do without peer review.

Think about it. What's the purpose of "enforcing standards". Just a
tick in some assurance box to say "we meet these standards"? Ot to
ensure something about the product quality?

No automated tool -- not for a while yet, anyway -- is going to pick
up comments such as:

# increment x
x += 1

or

# You are not expected to understand this.

The former is the sort of thing that any programmer might produce when
against a deadline and forced to comment their code. The latter is a
classic from a programming guru of old. An automatic checker that just
checks that the comment exists without understanding its contents
simply is not adding value but is rather petty bureaucracy that will
annoy the programmers.


-- 
Tim Rowe


From clp2 at rebertia.com  Fri Jul 10 14:53:39 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 11:53:39 -0700
Subject: Automate rsync w/ authentication
In-Reply-To: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
Message-ID: <50697b2c0907101153k69a6b5ej88fbd3a9993ed5d2@mail.gmail.com>

On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
> I am trying to automate rsync to backup server A from server B. ?I
> have set up a private/public key between the two servers so I don't
> have to enter a password when using rsync. ?Running rsync manually
> with the following command works fine:
> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>
> But when I try to do it with python, the subprocess simply returns the
> ssh -h output on stderr like I am passing some invalid syntax. ?What
> is wrong in my translation of rsync's -e command from shell to
> pythyon?
>
> #! /usr/bin/python
> from subprocess import Popen, PIPE
> rsyncExec = '/usr/bin/ssh'
> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
> dest = '/home/bry/tmp'
> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

Like many problems involving the subprocess module, I think you've
tokenized the arguments incorrectly. Try:

rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]

Note that the -e switch and its operand are separate arguments for the
purposes of POSIX shell tokenization.

Cheers,
Chris
-- 
http://blog.rebertia.com


From edreamleo at charter.net  Fri Jul 10 14:54:50 2009
From: edreamleo at charter.net (Edward K Ream)
Date: Fri, 10 Jul 2009 13:54:50 -0500
Subject: ANN: Leo 4.6 rc1 released
Message-ID: <D8M5m.54324$c82.37596@newsfe08.iad>

Leo 4.6 rc1 is now available at:
http://sourceforge.net/project/showfiles.php?group_id=3458&package_id=29106

Leo is a text editor, data organizer, project manager and much more. See:
http://webpages.charter.net/edreamleo/intro.html

The highlights of Leo 4.6:
--------------------------

- Cached external files *greatly* reduces the time to load .leo files.
- Leo now features a modern Qt interface by default.
  Leo's legacy Tk interface can also be used.
- New --config, --file and --gui command-line options.
- Leo tests syntax of .py files when saving them.
- Leo can now open any kind of file into @edit nodes.
- @auto-rst nodes allow easy editing of reStructuredText files.
- Properties of commanders, positions and nodes simplify programming.
- Improved Leo's unit testing framework.
- Leo now requires Python 2.5 or later.
- Dozens of small improvements and bug fixes.

Links:
------
Leo:      http://webpages.charter.net/edreamleo/front.html
Forum:    http://groups.google.com/group/leo-editor
Download: http://sourceforge.net/project/showfiles.php?group_id=3458
Bzr:      http://code.launchpad.net/leo-editor/
Quotes:   http://webpages.charter.net/edreamleo/testimonials.html
--------------------------------------------------------------------
Edward K. Ream   email:  edreamleo at yahoo.com
Leo: http://webpages.charter.net/edreamleo/front.html
--------------------------------------------------------------------




From jcd at sdf.lonestar.org  Fri Jul 10 14:56:48 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 14:56:48 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <h37rtd$etd$1@ger.gmane.org>
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<1247244628.8029.15.camel@aalcdl07>  <h37rtd$etd$1@ger.gmane.org>
Message-ID: <1247252208.11457.6.camel@aalcdl07>

On Fri, 2009-07-10 at 11:57 -0500, Robert Kern wrote:
> On 2009-07-10 11:50, J. Cliff Dyer wrote:
> > On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
> >> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
> >>
> >>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
> >>>
> >>>> Nobody says you shouldn't check your data. Only that "assert" is not
> >>>> the right way to do that.
> >>> "assert" is not the right way to check your *inputs*. It's a perfectly
> >>> reasonable way to check data which "should" be valid, as well as a way
> >>> to document what variables are supposed to contain.
> >> Where are those variables coming from?
> >>
> >> The distinction really boils down to this:
> >>
> >> * asserts should never fail. If there is any chance that an assertion
> >> might fail outside of test suites, then don't use assert.
> >>
> >
> > I'm no expert, but the more I read this thread, and the more I think on
> > it, the more I believe that asserts don't really need to exist outside
> > of test suites.
> 
> Actually, there is a good argument that one shouldn't use an assert statement in 
> test suites: code can have bugs that only show up under -O so you want to be 
> able to run your test suite under -O.
> 

That's an interesting point.  Presumably TestCase.assert_() doesn't
suffer from this defect?  Otherwise the entire unittest suite is
essentially broken by your argument.  I suppose I should have said one
should only raise AssertionErrors in test suites.  Practically speaking,
that's what a test suite is:  The place where you assert what the code
does.





From jcd at sdf.lonestar.org  Fri Jul 10 14:59:29 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 14:59:29 -0400
Subject: gett error message: "TypeError: 'int' object is not callable"
In-Reply-To: <3A693537-927D-44B1-840A-D97FACFB6809@pyth.net>
References: <e54c4461-c0b7-42fb-8542-cefd7bf5f89f@h18g2000yqj.googlegroups.com>
	<3A693537-927D-44B1-840A-D97FACFB6809@pyth.net>
Message-ID: <1247252369.11457.8.camel@aalcdl07>

On Thu, 2009-07-09 at 13:53 +0000, Fri?rik M?r J?nsson wrote:
> Look at:
> 
>    len = len(text)
> 
> You're overriding `len` (a built-in method), with an integer  
> (`len(text)`).  You then call:
> 
>    for i in range(len(fields)):
> 
> But `len` is no longer a callable, but merely an integer.
> 
> Regards,
> Fri?rik M?r
> 
> P.S. While this is a fairly obvious problem it's usually a good idea  
> to post working code and a traceback when requesting help.

While we're on the subject of good question posting form:  The body of
your post should contain all relevant information.  Please don't make
readers look back at the subject heading for the statement of the
problem.  Duplicating the statement of the problem in the subject and
the body is ok, but it really ought to be in the body.



From Scott.Daniels at Acm.Org  Fri Jul 10 14:59:50 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 11:59:50 -0700
Subject: tough-to-explain Python
In-Reply-To: <00733dd0$0$9710$c3e8da3@news.astraweb.com>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2944.1247223458.8015.python-list@python.org>	<007318de$0$9710$c3e8da3@news.astraweb.com>	<jKudnVwapbH0wcrXnZ2dnUVZ_gBi4p2d@pdx.net>
	<00733dd0$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <4-CdnSJso5pwEMrXnZ2dnUVZ_sVi4p2d@pdx.net>

Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 08:28:29 -0700, Scott David Daniels wrote:
>> Steven D'Aprano wrote:
>>> Even *soup stock* fits the same profile as what Hendrik claims is
>>> almost unique to programming. On its own, soup stock is totally
>>> useless. But you make it, now, so you can you feed it into something
>>> else later on.
>>> Or instant coffee.
>> I think I'll avoid coming to your house for a cup of coffee. :-)
> I meant the instant coffee powder is prepared in advance. It's useless on 
> it's own, but later on you feed it into boiling water, add sugar and 
> milk, and it's slightly less useless.

I know, but the image of even a _great_ soup stock with instant
coffee poured in, both appalled me and made me giggle.  So, I
thought I'd share.

--Scott David Daniels
Scott.Daniels at Acm.Org


From robert.kern at gmail.com  Fri Jul 10 15:02:58 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 10 Jul 2009 14:02:58 -0500
Subject: Clarity vs. code reuse/generality
In-Reply-To: <1247252208.11457.6.camel@aalcdl07>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>	<pan.2009.07.10.02.28.04.344000@nowhere.com>	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>	<1247244628.8029.15.camel@aalcdl07>
	<h37rtd$etd$1@ger.gmane.org> <1247252208.11457.6.camel@aalcdl07>
Message-ID: <h38392$5k4$1@ger.gmane.org>

On 2009-07-10 13:56, J. Cliff Dyer wrote:
> On Fri, 2009-07-10 at 11:57 -0500, Robert Kern wrote:
>> On 2009-07-10 11:50, J. Cliff Dyer wrote:
>>> On Fri, 2009-07-10 at 02:57 +0000, Steven D'Aprano wrote:
>>>> On Fri, 10 Jul 2009 03:28:04 +0100, Nobody wrote:
>>>>
>>>>> On Thu, 09 Jul 2009 04:57:15 -0300, Gabriel Genellina wrote:
>>>>>
>>>>>> Nobody says you shouldn't check your data. Only that "assert" is not
>>>>>> the right way to do that.
>>>>> "assert" is not the right way to check your *inputs*. It's a perfectly
>>>>> reasonable way to check data which "should" be valid, as well as a way
>>>>> to document what variables are supposed to contain.
>>>> Where are those variables coming from?
>>>>
>>>> The distinction really boils down to this:
>>>>
>>>> * asserts should never fail. If there is any chance that an assertion
>>>> might fail outside of test suites, then don't use assert.
>>>>
>>> I'm no expert, but the more I read this thread, and the more I think on
>>> it, the more I believe that asserts don't really need to exist outside
>>> of test suites.
>> Actually, there is a good argument that one shouldn't use an assert statement in
>> test suites: code can have bugs that only show up under -O so you want to be
>> able to run your test suite under -O.
>>
>
> That's an interesting point.  Presumably TestCase.assert_() doesn't
> suffer from this defect?  Otherwise the entire unittest suite is
> essentially broken by your argument.

It explicitly raises AssertionErrors. It does not use the assert statement.

> I suppose I should have said one
> should only raise AssertionErrors in test suites.  Practically speaking,
> that's what a test suite is:  The place where you assert what the code
> does.

Yup.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From mgi820 at motorola.com  Fri Jul 10 15:03:49 2009
From: mgi820 at motorola.com (Gary Duzan)
Date: Fri, 10 Jul 2009 19:03:49 +0000 (UTC)
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
Message-ID: <h383al$pln$1@engnntp2.cig.mot.com>

In article <3af970b1-b454-4d56-a33f-889ecfacacc5 at l28g2000vba.googlegroups.com>,
Bryan  <bryanvick at gmail.com> wrote:
>
>rsyncExec = '/usr/bin/ssh'
>source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
>dest = '/home/bry/tmp'
>rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

   I think you want -e and the ssh command to be separate args.
Something like:

rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source, dest]

or:

rshArgs = [ '-e', '/usr/bin/ssh -i /home/bry/keys/brybackup.key' ]
args = [rsyncExec, '-a', '-v', '--dry-run'] +  rshArgs + [ source, dest]

					Gary Duzan
					Motorola H&NM




From clp2 at rebertia.com  Fri Jul 10 15:11:12 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 12:11:12 -0700
Subject: Colour of output text
In-Reply-To: <h371ba$36l$1@aioe.org>
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
Message-ID: <50697b2c0907101211u5d6ddc80ra85857075c986217@mail.gmail.com>

On Fri, Jul 10, 2009 at 2:23 AM,
<garabik-news-2005-05 at kassiopeia.juls.savba.sk> wrote:
> Tim Harig <usernet at ilthio.net> wrote:
>> On 2009-07-09, Alex Rosslyn <black.linen99 at gmail.com> wrote:
>>> I would like to learn a way of changing the colour of a particular
>>> part of the output text. I've tried the following
>
>> On Unix operating systems this would be done through the curses interface:
>>
>> http://docs.python.org/library/curses.html
>
> Or using ANSI colour codes:
>
> colours = {
<snip>
> ? ? ? ? ? ?'beep' ? ? ? : ? ?"\007",

Sound is a color? Maybe if you have synaesthesia...

Cheers,
Chris
-- 
http://blog.rebertia.com


From walterbyrd at iname.com  Fri Jul 10 15:22:15 2009
From: walterbyrd at iname.com (walterbyrd)
Date: Fri, 10 Jul 2009 12:22:15 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
Message-ID: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>

I believe Guido himself has said that all indentions should be four
spaces - no tabs.

Since backward compatibility is being thrown away anyway, why not
enforce the four space rule?

At least that way, when I get python code from somebody else, I would
know what I am looking at, without having to do a hex dump, or
something.


From marty.musatov at gmail.com  Fri Jul 10 15:24:27 2009
From: marty.musatov at gmail.com (Musatov)
Date: Fri, 10 Jul 2009 12:24:27 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<c9f7f83e-7462-4780-ae6b-adf804d57e7a@y28g2000prd.googlegroups.com>
	<h36ki102d7m@news5.newsguy.com> <k%I5m.34251$Db2.2196@edtnps83>
Message-ID: <eec04d53-5eef-47ae-af91-256afe46ee38@l5g2000vbp.googlegroups.com>



Fran?ois Grondin wrote:
> "David Bernier" <david250 at videotron.ca> a ?crit dans le message de news:
> h36ki102d7m at news5.newsguy.com...
> > Musatov wrote:
> >> On Jul 9, 7:54 pm, David Bernier <david... at videotron.ca> wrote:
> >>> Musatov wrote:
> >>>> Los Angeles (AP) --MeAmI.org now has users in 50 countries following
> >>>> its adopted use in Pakistan.  The search engine has grown in
> >>>> popularity 10,000 fold following its Beta test launch three months ago
> >>>> in April, 2009. Supporters of the site claim it is better than rival
> >>>> Google upon which platform it is based. Controversy arose after
> >>>> MeAmI.org search code allowed users to search other users Google
> >>>> results with no advertising. "It is truly an innovative thing we are
> >>>> doing," said Founder and CEO, Martin Musatov. "Letting users search
> >>>> the results of other Google users immediately results in a level of
> >>>> accuracy and relevance above and beyond Google." Google changed their
> >>>> API following the launch or MeAmI.org and explored the possibility of
> >>>> blocking site access from MeAmI.org to Google search results but was
> >>>> unable to do so. Critics of MeAmI.org say what it is doing is
> >>>> tantamount to intellectual theft. When asked about this topper Musatov
> >>>> exclaimed, "The Internet was made for people, not companies." An
> >>>> analyst at Goldman Sachs says, requesting to remain anonymous,
> >>>> "MeAmI.org has a strong presence in promoting itself as a vehicle for
> >>>> global activism and to tell you the truth, this makes it much more
> >>>> likely an acquisition target than potential intellectual property
> >>>> violator." Google could not be reached for comment.
> >>> Mr. Musatov,  do you know who originally wrote the
> >>> article above?
> >>>
> >>> Thank you.
> >>>
> >>> David Bernier- Hide quoted text -
> >>>
> >>> - Show quoted text -
> >>
> >> Yes.
> >
> > Mr. Musatov, do you know the name of the person who
> > originally wrote the article above?
> >
> > Thank you.
> >
> > David Bernier
>
> Maybe Mr. Musatov should answer the following questions instead :
> 1. Did you write the article above?
> 2. If not, who did? And I don't want AP as the answer, but the name of the
> journalist.
>
> David, don't take it bad, but he answered your question with an accurate
> answer (yes), You gave him the opportunity to avoid the real answer and he
> took it. Based on Musatov's strange behavior and logic, don't expect more
> from him. Ask anyone else the same question and you'd get a real answer.
>
> BTW, my guess for question 2 would be the Masked Logician, Floetry,
> scriber77, or Professor X.
>
> Francois
1. Yes.


From aahz at pythoncraft.com  Fri Jul 10 15:26:14 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 12:26:14 -0700
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <h384km$p5j$1@panix3.panix.com>

In article <260f0f1f-1115-4db8-a955-74c9f459ecc3 at h30g2000vbr.googlegroups.com>,
walterbyrd  <walterbyrd at iname.com> wrote:
>
>I believe Guido himself has said that all indentions should be four
>spaces - no tabs.
>
>Since backward compatibility is being thrown away anyway, why not
>enforce the four space rule?

Probably the main reason is that Guido also hates non-functional code
changes because it messes up version history.  Not sure, though.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From kwmsmith at gmail.com  Fri Jul 10 15:29:09 2009
From: kwmsmith at gmail.com (Kurt Smith)
Date: Fri, 10 Jul 2009 14:29:09 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <c266a7930907101229g6ca75d24o94c243bafb28b51e@mail.gmail.com>

On Fri, Jul 10, 2009 at 2:22 PM, walterbyrd<walterbyrd at iname.com> wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.
>
> Since backward compatibility is being thrown away anyway, why not
> enforce the four space rule?
>
> At least that way, when I get python code from somebody else, I would
> know what I am looking at, without having to do a hex dump, or
> something.

What you propose has already been (forcefully) rejected:

http://www.python.org/dev/peps/pep-0666/


From clp2 at rebertia.com  Fri Jul 10 15:29:59 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 12:29:59 -0700
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <50697b2c0907101229l720e9c92y94a921dc5c58de52@mail.gmail.com>

On Fri, Jul 10, 2009 at 12:22 PM, walterbyrd<walterbyrd at iname.com> wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.

That's a (very good) recommendation at most.
http://www.python.org/dev/peps/pep-0666/

Cheers,
Chris
-- 
http://blog.rebertia.com


From tjreedy at udel.edu  Fri Jul 10 15:30:04 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 15:30:04 -0400
Subject: help me to find the error
In-Reply-To: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
References: <3d4ff96c0907100241p1f0a3b9eueef3157989f7e98@mail.gmail.com>
Message-ID: <h384rr$asn$1@ger.gmane.org>

jhinak sen wrote:
> hi,
> i am a beginner in python language,

Welcome to Python.
> 
> i am trying with this programme :
> to find the addition and mean from a data set in a file and writing the 
> mean and sum in some other file :

This is three things: input data from, perform calculation, output data 
to file. I would start simpler. See below.

You did two things right that too many people do not do.

1. You posted a complete chunk of code.

> ""
> *#! /usr/bin/env python
> 
> import re
> import cPickle as p
> import math
> from numpy import *

You never use these.
> 
> f0= open("temp9","r+").readlines()

[snip]
> f0.close()
> f2.close()*

2. You posted the complete traceback (instead of the annoying 'program 
didn't work ;-).

> ""    *Traceback (most recent call last):
>   File "./temporary1.py", line 24, in <module>
>     f0.close()
> AttributeError: 'list' object has no attribute 'close'*
> ""
> 
> please help to to find the error.

Seeing that, any of us could tell you thought f0 was a file but it was 
actually a list. Looking back up through the code, people found the 
definition -- the output of file.readlines, which is a list.

> or suggest some simpler or better way

Develop more incrementally. If you edit with IDLE, for instance, and hit 
RUN (F5), it takes about a second to see the result for a small program 
like this. I would have suggested starting with

data = [(1,2), (3,4)]
...
print "input: ", a, b, "output: ", tot, ave

and fill in ... until the output was correct.

Then change data to ['1 2', '3 4'] and revise until correct.

At that point, change data to open(....) and the program should 
otherwise work without change because a list of strings and a file are 
both iterators that produce a sequence of strings.

Now, if you want, worry about formating the output, removing the echo of 
the input.

Very last, send to output to a disk file instead of the screen. For 
development, that is a nuisance because it takes time to open the file 
to check results. So only do that when you already know the results are 
correct. Note that real programs used repeatedly ofter do not hard code 
an output file. If run from a command line in a comman window, screen 
output can be redirected to a file with '>': "myprog > outfile".

Terry Jan Reedy



From piet at cs.uu.nl  Fri Jul 10 15:43:21 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 10 Jul 2009 21:43:21 +0200
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
Message-ID: <m2iqi08gti.fsf@cs.uu.nl>

>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:

>CR> On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
>>> I am trying to automate rsync to backup server A from server B. ?I
>>> have set up a private/public key between the two servers so I don't
>>> have to enter a password when using rsync. ?Running rsync manually
>>> with the following command works fine:
>>> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>>> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>>> 
>>> But when I try to do it with python, the subprocess simply returns the
>>> ssh -h output on stderr like I am passing some invalid syntax. ?What
>>> is wrong in my translation of rsync's -e command from shell to
>>> pythyon?
>>> 
>>> #! /usr/bin/python
>>> from subprocess import Popen, PIPE
>>> rsyncExec = '/usr/bin/ssh'
>>> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
>>> dest = '/home/bry/tmp'
>>> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

>CR> Like many problems involving the subprocess module, I think you've
>CR> tokenized the arguments incorrectly. Try:

>CR> rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>CR> args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]

>CR> Note that the -e switch and its operand are separate arguments for the
>CR> purposes of POSIX shell tokenization.

I think you should have only one kind of quotes in rshArg:
rshArg = "/usr/bin/ssh -i /home/bry/keys/brybackup.key"

I haven't tried it, however, but this is just how Unix works.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From clp2 at rebertia.com  Fri Jul 10 15:47:59 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 12:47:59 -0700
Subject: Automate rsync w/ authentication
In-Reply-To: <m2iqi08gti.fsf@cs.uu.nl>
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
	<m2iqi08gti.fsf@cs.uu.nl>
Message-ID: <50697b2c0907101247g274c270bocfda4e82d3fb6617@mail.gmail.com>

On Fri, Jul 10, 2009 at 12:43 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:
>
>>CR> On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
>>>> I am trying to automate rsync to backup server A from server B. ?I
>>>> have set up a private/public key between the two servers so I don't
>>>> have to enter a password when using rsync. ?Running rsync manually
>>>> with the following command works fine:
>>>> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>>>> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>>>>
>>>> But when I try to do it with python, the subprocess simply returns the
>>>> ssh -h output on stderr like I am passing some invalid syntax. ?What
>>>> is wrong in my translation of rsync's -e command from shell to
>>>> pythyon?
>>>>
>>>> #! /usr/bin/python
>>>> from subprocess import Popen, PIPE
>>>> rsyncExec = '/usr/bin/ssh'
>>>> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
>>>> dest = '/home/bry/tmp'
>>>> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>>> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
>
>>CR> Like many problems involving the subprocess module, I think you've
>>CR> tokenized the arguments incorrectly. Try:
>
>>CR> rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>CR> args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]
>
>>CR> Note that the -e switch and its operand are separate arguments for the
>>CR> purposes of POSIX shell tokenization.
>
> I think you should have only one kind of quotes in rshArg:
> rshArg = "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>
> I haven't tried it, however, but this is just how Unix works.

Ah, indeed, I think you're probably right. Just goes to show it's not
always easy to get exactly right.

Cheers,
Chris
-- 
http://blog.rebertia.com


From jcd at sdf.lonestar.org  Fri Jul 10 16:12:11 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 10 Jul 2009 16:12:11 -0400
Subject: Nested Classes and Instances
In-Reply-To: <m3r5woh3s4.fsf@uriel.graune.org>
References: <m3r5woh3s4.fsf@uriel.graune.org>
Message-ID: <1247256731.11457.76.camel@aalcdl07>

On Fri, 2009-07-10 at 19:00 +0200, Manuel Graune wrote:
> Hello,
> 
> as an example of what I would like to achieve, think of a street
> where each house has a door and a sign with a unique (per house)
> number on it. I tried to model this like this:
> 
> class House(object):
>     class Door(object):
>         def __init__(self,color):
>              self.color=color
>     class Sign(object):
>         def __init__(self,text):
>              self.text=text
>     def __init__(self, doorcolor,housenumber):
>         self.housenumber=housenumber
>         self.door=House.Door(doorcolor)
>         self.sign=House.Sign(housenumber)
> 
> house1=House("red","1")
> house2=House("blue","2")
> 

Don't do it like that.  Keep your classes independent.  Many houses can
have doors, and there's no reason to redefine the concept of Doors for
each one.  Same goes for Signs.  

class House(object):
    def __init__(self, doorcolor, housenumber):
        self.door = Door(doorcolor)
        self.sign = Sign(housenumber)
        self.number = housenumber

class Door(object):
    def __init__(self, color):
        self.color = color

class Sign(object):
    def __init__(self, inscription):
        self.inscription = str(housenumber)



(Something like that)

Cheers,
Cliff




> Well, so far, so good. Now, what I'd like to achive is that the text of
> the "sign" changes whenever the variable "housenumber" of the
> "parent-instance" changes or  that
> "house1.sign.text" is a reference/pointer to "house1.housenumber"
> 
> Thanks in advance,
> 
> Manuel
> 
> 
> 
> -- 
> A hundred men did the rational thing. The sum of those rational choices was
> called panic. Neal Stephenson -- System of the world
> http://www.graune.org/GnuPG_pubkey.asc
> Key fingerprint = 1E44 9CBD DEE4 9E07 5E0A  5828 5476 7E92 2DB4 3C99



From bryanvick at gmail.com  Fri Jul 10 16:16:02 2009
From: bryanvick at gmail.com (Bryan)
Date: Fri, 10 Jul 2009 13:16:02 -0700 (PDT)
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
	<m2iqi08gti.fsf@cs.uu.nl>
Message-ID: <f370a703-2864-471f-bab4-4774981458ce@b14g2000yqd.googlegroups.com>

On Jul 10, 12:43?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Chris Rebert <c... at rebertia.com> (CR) wrote:
> >CR> On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanv... at gmail.com> wrote:
> >>> I am trying to automate rsync to backup server A from server B. ?I
> >>> have set up a private/public key between the two servers so I don't
> >>> have to enter a password when using rsync. ?Running rsync manually
> >>> with the following command works fine:
> >>> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
> >>> r... at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>
> >>> But when I try to do it with python, the subprocess simply returns the
> >>> ssh -h output on stderr like I am passing some invalid syntax. ?What
> >>> is wrong in my translation of rsync's -e command from shell to
> >>> pythyon?
>
> >>> #! /usr/bin/python
> >>> from subprocess import Popen, PIPE
> >>> rsyncExec = '/usr/bin/ssh'
> >>> source = 'r... at 10.0.45.67:/home/bry/jquery.lookup'
> >>> dest = '/home/bry/tmp'
> >>> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> >>> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
> >CR> Like many problems involving the subprocess module, I think you've
> >CR> tokenized the arguments incorrectly. Try:
> >CR> rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> >CR> args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]
> >CR> Note that the -e switch and its operand are separate arguments for the
> >CR> purposes of POSIX shell tokenization.
>
> I think you should have only one kind of quotes in rshArg:
> rshArg = "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
>
> I haven't tried it, however, but this is just how Unix works.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

I tried removing the internal quotes, and splitting '-e' from the
other arguments.  I still get the same ssh -h output however:

rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source,
dest]
p = Popen(args, stdout=PIPE, stderr=PIPE)



From tjreedy at udel.edu  Fri Jul 10 16:27:12 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:27:12 -0400
Subject: tough-to-explain Python
In-Reply-To: <pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2931.1247195266.8015.python-list@python.org>
	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
Message-ID: <h3886v$ki0$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Thu, 09 Jul 2009 23:07:34 -0400, Terry Reedy wrote:

>>
>> The is *not* a bug is Bentley program.

This is *not* a bug in Bentley's program.

> Wow. That's an impressive set of typos :)

3. Way beneath my usual standards ;-)

>> It is a bug in bad, buggy, insane
>> integer arithmetic implementations. low + high should either return the
>> right answer, as it will in Python, or raise an overflow error.
> 
> Is binary search *supposed* to raise an overflow error if given more than 
> 2**30 elements? 

No. it is supposed to work, and Bentley's program will work if lo and hi 
are actually integers, as his program presupposes, and not residue 
classes mislabeled 'int'.

> Is there something special about OverflowError that is "better" than 
> ArrayIndexOutOfBoundsException?

Wrong comparison. The actual alternative to OverflowError is a negative 
number as the sum of two positive numbers. If one claims that a and b 
are positive ints, then returning a negative is a bug. The index 
exception was a side effect, in Java, of using the negative as an index. 
In C, the side effect was a segmentation fault. Do you seriously 
question that OverflowError is better than seg faulting? A different 
program could go on to silently return a wrong answer. Perhaps it would 
say to go west instead of east, or to reduce a medical dosage instead of 
raising it.

Note that negative ints are legal indexes in Python, so that if any 
Python version ever had ints that wrapped instead of overflowing or 
returning a long, then the program would not necessarily stop.

> but there's no reason to imagine that the book will assume -- or even 
> state as a requirement for binary search -- that addition will never 
> overflow.

Bentley assumed that if (lo+hi)/2 were successfully calculated, then it 
would be a positive number between lo and hi, and therefore a legal index.

The dirty secret of computing is that some languages do not have integer 
types. They do not even have restricted-range integer types, which would 
noisily fail when they cannot perform an operation. They only have 
residue class types, which are something else, and which can give 
bizarre results if one mindlessly uses them as if they really were 
restricted-range integers. When one wants integer operations, every 
operation with two residue-class variables has a potential *silent* bug. 
Being relieved of the burden of constantly keeping this in mind is one 
reason I use Python.

Float types are usually restricted range types. A huge_float + 
huge_float may raise overflow, but never returns a negative float.

Bentley assumed that indexes hi and lo are integers. If one uses 
restricted range integers that are too large, then lo+hi could fail 
gracefully with an appropriate effor message. I would not consider that 
a bug, bug a limitation due to using limited-range numbers. If one uses 
residue classes instead of integers, and makes no adjustment, I consider 
it wrong to blame Bentley.

Terry Jan Reedy



From vivainio at gmail.com  Fri Jul 10 16:30:37 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Fri, 10 Jul 2009 13:30:37 -0700 (PDT)
Subject: ANN: Leo 4.6 rc1 released
References: <D8M5m.54324$c82.37596@newsfe08.iad>
Message-ID: <56d676ba-b2fc-4288-a37e-0825291369e0@n11g2000yqb.googlegroups.com>

On Jul 10, 9:54?pm, "Edward K Ream" <edream... at charter.net> wrote:

> The highlights of Leo 4.6:
> --------------------------

> - Leo now features a modern Qt interface by default.
> ? Leo's legacy Tk interface can also be used.

And to drive home this point (Qt ui), some screenshots for the
visually oriented:

http://imgbin.org/images/625.png
http://imgbin.org/images/626.png
http://imgbin.org/images/627.png


From tjreedy at udel.edu  Fri Jul 10 16:32:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:32:17 -0400
Subject: can i write a assemly language programs in python
In-Reply-To: <4A572AA1.7010207@ieee.org>
References: <a97ce0940907090017r2d918e58u4bdbcd6729a8bf68@mail.gmail.com>	<4A55F392.3080404@ieee.org>	<h35a1h$gus$1@ger.gmane.org>
	<4A572AA1.7010207@ieee.org>
Message-ID: <h388gg$lf8$1@ger.gmane.org>

Dave Angel wrote:
> Terry Reedy wrote:

> If you mean dis.dis() that only gives you byte code.

No, dis is a disassembler and it gives readable assembly code, not the 
raw numerical bytes. Its purpose is to make byte code + other parts of 
the code object humanly readable.

As far as I know, there is no assembler that would turn the exact output 
of dis back to its input.

tjr



From Scott.Daniels at Acm.Org  Fri Jul 10 16:38:06 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 13:38:06 -0700
Subject: finding most common elements between thousands of multiple arrays.
In-Reply-To: <0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
	<0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>
Message-ID: <muOdnciPf_tpOcrXnZ2dnUVZ_uNi4p2d@pdx.net>

Raymond Hettinger wrote:
> [Scott David Daniels]
>> def most_frequent(arr, N): ...
> In Py2.4 and later, see heapq.nlargest().
I should have remembered this one

> In Py3.1, see collections.Counter(data).most_common(n)
This one is from Py3.2, I think.


--Scott David Daniels
Scott.Daniels at Acm.Org


From tjreedy at udel.edu  Fri Jul 10 16:47:06 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:47:06 -0400
Subject: Query regarding set([])?
In-Reply-To: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
References: <e40e7b68-6fac-412d-a0b7-2ba72a55dc5c@p29g2000yqh.googlegroups.com>
Message-ID: <h389ca$nqd$1@ger.gmane.org>

vox wrote:
> Hi,
> I'm contsructing a simple compare-script and thought I would use set
> ([]) to generate the difference output. But I'm obviosly doing
> something wrong.
> 
> file1 contains 410 rows.
> file2 contains 386 rows.
> I want to know what rows are in file1 but not in file2.
> 
> This is my script:
> s1 = set(open("file1"))
> s2 = set(open("file2"))
> s3 = set([])
> s1temp = set([])
> s2temp = set([])
> 
> s1temp = set(i.strip() for i in s1)
> s2temp = set(i.strip() for i in s2)
> s3 = s1temp-s2temp
> 
> print len(s3)
> 
> Output is 119. AFAIK 410-386=24. What am I doing wrong here?

Assuming that every line in s2 is in s1. If there are lines in s2 that 
are not in s1, then the number of lines in s1 not in s2 will be larger 
than 24. s1 - s2 subtracts the intersection of s1 and s2.



From tjreedy at udel.edu  Fri Jul 10 16:53:53 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 16:53:53 -0400
Subject: problem with keys combination!
In-Reply-To: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
Message-ID: <h389p0$oph$1@ger.gmane.org>

Alex wrote:
> Hi at all,
>   I made a simple program that make a screenshot of Desktop and use it
> as fullscreen background and then a ball erase image making illusion
> that erase Desktop. The program working fine and I succesfully blocked
> all keys but I have a problem with hotkey combination Ctrl-Alt-
> Del...that bypass my FullScreen Application.

Blocking Ctrl-Alt-Del leaves the power switch or maybe the plug as the 
only way for the user to regain control. Why would you want to do that?



From ivlenin at gmail.com  Fri Jul 10 16:54:08 2009
From: ivlenin at gmail.com (I V)
Date: 10 Jul 2009 22:54:08 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2931.1247195266.8015.python-list@python.org>
	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
	<mailman.2983.1247257646.8015.python-list@python.org>
Message-ID: <4a57aa70@news.x-privat.org>

On Fri, 10 Jul 2009 16:27:12 -0400, Terry Reedy wrote:
> a bug, bug a limitation due to using limited-range numbers. If one uses
> residue classes instead of integers, and makes no adjustment, I consider
> it wrong to blame Bentley.

But it was Bentley himself who used the C int type, so it hardly seems 
unreasonable to blame him.


From Scott.Daniels at Acm.Org  Fri Jul 10 17:07:28 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 14:07:28 -0700
Subject: Sorry about that, the Counter class is there.
In-Reply-To: <muOdnciPf_tpOcrXnZ2dnUVZ_uNi4p2d@pdx.net>
References: <c5332c9b-2348-4194-bfa0-d70c7710765d@x3g2000yqa.googlegroups.com>
	<6faf39c90907040104v58792755had60b5ac5a873975@mail.gmail.com>
	<mailman.2602.1246701345.8015.python-list@python.org>
	<5L6dnWWjU4HF_tLXnZ2dnUVZ_hidnZ2d@pdx.net>
	<0360b017-72a4-44f9-8779-0299de5b0c04@i8g2000pro.googlegroups.com>
	<muOdnciPf_tpOcrXnZ2dnUVZ_uNi4p2d@pdx.net>
Message-ID: <UaSdnRCTVf5KNsrXnZ2dnUVZ_uKdnZ2d@pdx.net>

Scott David Daniels wrote:
> Raymond Hettinger wrote:
>> [Scott David Daniels]
>>> def most_frequent(arr, N): ...
>> In Py2.4 and later, see heapq.nlargest().
> I should have remembered this one
> 
>> In Py3.1, see collections.Counter(data).most_common(n)
> This one is from Py3.2, I think.

Oops -- egg all over my face.  I thought I was checking with 3.1, and it
was 2.6.2.  I _did_ make an explicit check, just poorly.

Again, apologies.

--Scott David Daniels
Scott.Daniels at Acm.Org


From noen  Fri Jul 10 17:16:13 2009
From: noen (earthlink)
Date: Fri, 10 Jul 2009 17:16:13 -0400
Subject: 2.4 VS 3.1 for simple print
Message-ID: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>

Why does 

print "GarbageCollector: collected %d objects." % (gc.collect())

work in 2.4 but not in 3.1?


From Scott.Daniels at Acm.Org  Fri Jul 10 17:24:42 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 10 Jul 2009 14:24:42 -0700
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <h37eat$qmm$1@lec.cs.unibo.it>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
	<h37eat$qmm$1@lec.cs.unibo.it>
Message-ID: <BbWdnQyDurB8MsrXnZ2dnUVZ_j6dnZ2d@pdx.net>

jacopo mondi wrote:
> Roger Binns wrote:
>> jacopo mondi wrote:
>>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>>> add support to an experimental socket family.
>> You may find it considerably easier to use ctypes since that will avoid
>> the need for any patching.  You'll also be able to control how read and
>> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
>> os.fdopen to convert your raw file descriptor into a Python file object
>> if appropriate.

The typical Python way of dealing with this is an additional module, not
a modified module placed back in the library.  So, take the sources and
edit, but change the module name.  Even better is figure out how to
use _socket.pyd, to create a smaller _socketexpmodule.c and use that.

--Scott David Daniels
Scott.Daniels at Acm.Org


From clp2 at rebertia.com  Fri Jul 10 17:28:07 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 10 Jul 2009 14:28:07 -0700
Subject: 2.4 VS 3.1 for simple print
In-Reply-To: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
Message-ID: <50697b2c0907101428q76fcef47me9e389c5aeee66f3@mail.gmail.com>

On Fri, Jul 10, 2009 at 2:16 PM, earthlink<noen> wrote:
> Why does
> print "GarbageCollector: collected %d objects." % (gc.collect())
>
> work in 2.4 but not in 3.1?

Define "works". What error are you getting? Include the exact message
and full error traceback.
Or if no exception is being raised, explain exactly how is it behaving
differently from your expectations.

Cheers,
Chris
-- 
http://blog.rebertia.com


From martin at v.loewis.de  Fri Jul 10 17:30:53 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Fri, 10 Jul 2009 23:30:53 +0200
Subject: 2.4 VS 3.1 for simple print
In-Reply-To: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
Message-ID: <4a57b30e$0$15912$9b622d9e@news.freenet.de>

> Why does
> print "GarbageCollector: collected %d objects." % (gc.collect())
> 
> work in 2.4 but not in 3.1?

Because print is a function in 3.1, so you have to follow it with
a parenthesis.

Regards,
Martin


From lkcl at lkcl.net  Fri Jul 10 17:37:46 2009
From: lkcl at lkcl.net (Luke Kenneth Casson Leighton)
Date: Fri, 10 Jul 2009 21:37:46 +0000
Subject: [ANN] Pyjamas 0.6pre1 ALPHA release of Pyjamas Widget Set
Message-ID: <ced5f0f60907101437t69b52b3ct5c6ae713e377a4c6@mail.gmail.com>

http://pyjs.org - Pyjamas is a port of GWT to Python that can run
applications both on the Desktop (like python-gtk2) and in all
major Web Browsers (as javascript).

This is an alpha release - 0.6pre1 - of the Pyjamas Web Widget Set.

It is a significant upgrade, incorporating Pyjamas Desktop which
can now use Mozilla XULRunner as well as PyWebKitGtk as the
browser engine.
Significant enhancements have been made to the javascript
compiler, which bring python strict features as well as a
relaxed (and faster) compile-time option.

The reason for the 0.6 pre-release is due to the number of
features and improvements added.

Many thanks to Kees, Lovely Systems, and all the people from
EuroPython 2009 who have helped contribute and generally make
Pyjamas fun to work with.

Downloads are available from:
http://code.google.com/p/pyjamas
http://sourceforge.net/projects/pyjamas
http://pypi.python.org/pypi/Pyjamas


From matt.dubins at sympatico.ca  Fri Jul 10 17:39:14 2009
From: matt.dubins at sympatico.ca (inkhorn)
Date: Fri, 10 Jul 2009 14:39:14 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
Message-ID: <e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>

Thanks all!!  I found the following to be most helpful:  any(substr in
long_string for substr in list_of_strings)

This bang-for-your-buck is one of the many many reasons why I love
Python programming :)

Matt Dubins


From piet at cs.uu.nl  Fri Jul 10 17:46:23 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 10 Jul 2009 23:46:23 +0200
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<mailman.2973.1247252021.8015.python-list@python.org>
	<m2iqi08gti.fsf@cs.uu.nl>
	<f370a703-2864-471f-bab4-4774981458ce@b14g2000yqd.googlegroups.com>
Message-ID: <m2ab3c8b4g.fsf@cs.uu.nl>

>>>>> Bryan <bryanvick at gmail.com> (B) wrote:

>B> I tried removing the internal quotes, and splitting '-e' from the
>B> other arguments.  I still get the same ssh -h output however:

>B> rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
>B> args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source,
>B> dest]
>B> p = Popen(args, stdout=PIPE, stderr=PIPE)

For me it works. Of course I substituted local server names, file names
etc. I run this on Mac OS X 10.4.11. The server is some Linux system.

------------------------------------------------------------------------
#! /usr/bin/env python

from subprocess import Popen, PIPE
rsyncExec = '/usr/local/bin/rsync'

source = 'xxx.cs.uu.nl:/users/piet/yyyyyy'
dest = '/Users/piet/TEMP/test.rsync'

rshArg = '/usr/bin/ssh -i /Users/piet/.ssh/id_rsa'

args = [rsyncExec, '-a', '-v', '-e', rshArg, source, dest]

try:
	p = Popen(args, stdout=PIPE, stderr=PIPE)
	print 'rsync running with pid %s' % p.pid
	out, err = p.communicate()
	print 'Errors: %s' % err
	print 'Output: %s' % out
except Exception:
	print 'Error running rsync'
------------------------------------------------------------------------

It just copies the file.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From timlee126 at yahoo.com  Fri Jul 10 17:52:09 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 10 Jul 2009 14:52:09 -0700 (PDT)
Subject: main in Python
Message-ID: <159869.41728.qm@web63104.mail.re1.yahoo.com>


Hi,
I learned that a Python script is written in this way:
def main():
    ...
if __name__ == "__main__":
    main()

Today, when I read a script, I found it has a different way:

def main():
    ...

main()

It can run as well. Can someone explain why and the rules that Python scripts get run?

Thanks and regards,
Tim


      


From jjposner at optimum.net  Fri Jul 10 18:01:06 2009
From: jjposner at optimum.net (John Posner)
Date: Fri, 10 Jul 2009 18:01:06 -0400
Subject: Tkinter only: table widget with canvas...
In-Reply-To: <mailman.10638.1247239202.8014.python-list@python.org>
References: <mailman.10638.1247239202.8014.python-list@python.org>
Message-ID: <4A57BA22.5030201@optimum.net>

Hi --
>
> a) Assume I would have some different widgets to add per row. How
>     do I get the maximum row height?

If you are placing widgets in a table like this:

  w.grid(row=a, column=b)

... where the *master* of widget "w" is a Tkinter.Frame named 
"table_frm", then you can determine the height of row N like this:

   table_frm.grid_bbox(column=0, row=N)

Quoth the grid_bbox() documentation (with the object name changed for 
clarity):

    Returns a 4-tuple describing the bounding box of some or all
    of the grid system in widget |/|table_frm|/|. The first two numbers 
returned
    are the /|x|/ and /|y|/ coordinates of the upper left corner of the 
area,
    and the second two numbers are the width and height.


So the final member of the 4-tuple is the height you want.
>
> b) Assume something like a label in one column. The length of all
> texts
>     in a column will differ. How do I choose the maxium column width?

The third member of grid_bbox() 4-tuple is the cell-width. So just find 
the maximum of these values:

   table_frm.grid_bbox(column=0, row=0)[2]
   table_frm.grid_bbox(column=1, row=0)[2]
   table_frm.grid_bbox(column=2, row=0)[2]
   ...

>
> c) Placing headers in a canvas does not look like a good idea because
>     I don't want to scroll the headers. Am I right?
>     c.1) How do I place a none scrollable header in a canvas?  or
>     c.2) How do I place all headers outside the canvas correctly above
> the relating column?
>

"c.2" is what you want. Again, if the table is in a Tkinter.Frame named 
"frm", you want to create an outer frame, then pack a header frame and 
the table frame into it, vertically:

    rt = Tk()
    outer_frm = Frame(rt)
    outer_frm.pack(expand=True, fill=BOTH)
    header_frm = Frame(outer_frm, height=25)
    header_frm.pack(side=TOP)
    table_frm = Frame(outer_frm)
    table_frm.pack(side=TOP)


(For scrolling, consider making "table_frm" a Pmw.ScrolledFrame instead 
of a Tkinter.Frame.)

As for getting the heading labels correctly placed above the columns, 
pack correctly-sized subframes (Tkinter.Frame's) into "header_frm". To 
determine the size of a column, use grid_bbox() again:

    BBOX_WIDTH_COMPONENT = 2
    header_subfrm = Frame(header_frm, relief=GROOVE, bd=2)
    header_subfrm['width'] = \
         table_frm.grid_bbox(column=N, row=0)[BBOX_WIDTH_COMPONENT]
  
Then, use place() to center a label within the subframe:

    header_label = Label(header_subfrm, text="Heading")
    header_label.place(relx=0.5, rely=0.5, anchor=CENTER)

There's a working app at http://cl1p.net/tkinter_table_headers/

-John




From ethan at stoneleaf.us  Fri Jul 10 18:11:08 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 10 Jul 2009 15:11:08 -0700
Subject: Clarity vs. code reuse/generality
In-Reply-To: <006eb26f$0$9711$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<h2nqpf$d91$1@reader1.panix.com>	<mailman.2688.1246883548.8015.python-list@python.org>	<006e795f$0$9711$c3e8da3@news.astraweb.com>	<h2uhcb$blq$1@panix3.panix.com>
	<006eb26f$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <4A57BC7C.5030705@stoneleaf.us>

Steven D'Aprano wrote:
> On Mon, 06 Jul 2009 21:02:19 -0700, Aahz wrote:
> 
> 
>>In article <006e795f$0$9711$c3e8da3 at news.astraweb.com>, Steven D'Aprano 
>><steve at REMOVE-THIS-cybersource.com.au> wrote:
>>
>>>On Mon, 06 Jul 2009 14:32:10 +0200, Jean-Michel Pichavant wrote:
>>>
>>>>kj wrote:
>>>>
>>>>>    sense = cmp(func(hi), func(lo))
>>>>>    assert sense != 0, "func is not strictly monotonic in [lo, hi]"
>>>>
>>>>As already said before, unlike other languages, sense in english does
>>>>**not** mean direction. You should rewrite this part using a better
>>>>name. Wrong informations are far worse than no information at all.
>>>
>>>Absolutely.
>>>
>>
>>>From Webster's Dictionary:
>>
>>>     8. (Geom.) One of two opposite directions in which a line,
>>>     surface, or volume, may be supposed to be described by the motion
>>>     of a point, line, or surface.
>>>     [1913 Webster]
>>>
>>>
>>>And from WordNet:
>>>
>>>    2: the meaning of a word or expression; the way in which a word
>>>       or expression or situation can be interpreted
>>>
>>>Both meanings are relevant to the way KJ is using the word. Please take
>>>your own advice and stop giving wrong information. As a native English
>>>speaker, I had no difficulty understanding the meaning of "sense" in the
>>>sense intended by KJ.
>>
>>As another native English speaker, I agree with Jean-Michel; this is the
>>first time I've seen "sense" used to mean direction.
> 
> 
> 
> Just goes to show you learn something new all the time.
> 
> http://www.merriam-webster.com/dictionary/sense
> 
>     7: one of two opposite directions especially of motion (as 
>     of a point, line, or surface)
> 
> 
> http://dictionary.reference.com/browse/sense
> 
>     18.  Mathematics. one of two opposite directions in which 
>     a vector may point.
> 
> 
> 
> Paraphrasing the Collins Dictionary of Mathematics:
> 
> The sense of a vector is the sign of the measure, contrasted with the 
> magnitude. Thus the vectors AB and BA have the same direction but 
> opposite sense. Sense is also used to distinguish clockwise and anti-
> clockwise.
> 
> Sense is, if you like, a "signed direction". "Towards north" (say) as 
> opposed to "along the north-south axis".
> 

This also illustrates the importance of knowing your target audience.  I 
have also not seen "sense" used this way before, and from the placement 
in the dictionaries I would venture to say it's not common usage outside 
of mathematics and the sciences.

Of course, since kj is teaching biologists, odds are decent they know 
what he's talking about.

~Ethan~


From usernet at ilthio.net  Fri Jul 10 18:13:00 2009
From: usernet at ilthio.net (Tim Harig)
Date: Fri, 10 Jul 2009 22:13:00 GMT
Subject: main in Python
References: <mailman.2989.1247263131.8015.python-list@python.org>
Message-ID: <M1P5m.3484$Ad2.405@nlpi067.nbdc.sbc.com>

On 2009-07-10, Tim <timlee126 at yahoo.com> wrote:
[RE-ORDERED]
> It can run as well. Can someone explain why and the rules that Python
> scripts get run?

Everything gets run by default.  The def syntax defines functions but does
not run them -- they are only run when they are called

> Today, when I read a script, I found it has a different way:
> def main():
>     ...
>
> main()

This define main and then runs it.

> def main():
>     ...
> if __name__ == "__main__":
>     main()

This defines main but it only runs it if __name__ == "__main" which will
only happen if the script is called directly:

./sample.py
or
python sample.py
etc.

This form is often preferred because it allows you to import definitions
the module without running the code within the main funciton module.
That way the same file can be used as a standalone program or as an
importable module.


From david250 at videotron.ca  Fri Jul 10 18:26:36 2009
From: david250 at videotron.ca (David Bernier)
Date: Fri, 10 Jul 2009 18:26:36 -0400
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
Message-ID: <h38f6t01fj2@news7.newsguy.com>

scriber77 at yahoo.com wrote:
[...]

> community. But perhaps he is trying to see things a bit differently
> and is just not getting the feedback he needs, so he is throwing
> tantrums apparently across USENET.
> 
> Like I said before, I am just trying to do right by this person who
> contacted me, and seemed to be a decent person with a genuine interest
> in mathematics. He was very respectful.
> 
> Alas, I am at a loss on what specific feedback to give him on his
> paper as though I am a professor of Mathematics, Computer Science is
> not my specialty.
> 
> I told him I would try to get him some feedback on the equations on
> page 3.  Would any of you be so kind to help me?
> 
> Here is the paper: http://MeAmI.org/pversusnp.pdf
> 
> I do thank you for your time.
> 
> Good day,
> 
> Professor X

This is what there is at the bottom of page 3:

<< Conclusion: Binary revisions are allowed given the above formulas. >>

So I don't understand the proposed solution for the "P = NP"
problem.

David Bernier


From liukis at usc.edu  Fri Jul 10 19:28:06 2009
From: liukis at usc.edu (Maria Liukis)
Date: Fri, 10 Jul 2009 16:28:06 -0700
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty"
	exception
Message-ID: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>

Hello,

Has anybody seen an exception "OSError: [Errno 39] Directory not  
empty" raised by shutil.rmtree? The code that raised an exception  
creates a lot of directories with files, and then removes them. I got  
an exception when one of such directories was removed. Here is the  
backtrace:

     shutil.rmtree(filename)
   File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
     onerror(os.rmdir, path, sys.exc_info())
   File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
     os.rmdir(path)
OSError: [Errno 39] Directory not empty: /path/to/my/dir

According to the documentation, shutil.rmtree should not care about  
directory being not empty.

Thanks for the help,
Masha
--------------------
liukis at usc.edu



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/557f5e85/attachment-0001.html>

From ben+python at benfinney.id.au  Fri Jul 10 19:35:13 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 11 Jul 2009 09:35:13 +1000
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <87ljmwm7ri.fsf@benfinney.id.au>

walterbyrd <walterbyrd at iname.com> writes:

> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.

Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
with a simple imperative::

    Use 4 spaces per indentation level.

it soon afterward takes a more nuanced tone::

    The most popular way of indenting Python is with spaces only. The
    second-most popular way is with tabs only. Code indented with a
    mixture of tabs and spaces should be converted to using spaces
    exclusively. When invoking the Python command line interpreter with
    the -t option, it issues warnings about code that illegally mixes
    tabs and spaces. When using -tt these warnings become errors. These
    options are highly recommended!

    For new projects, spaces-only are strongly recommended over tabs.
    Most editors have features that make this easy to do.

    <URL:http://www.python.org/dev/peps/pep-0008/>

> Since backward compatibility is being thrown away anyway

That implies a level of abandon that was (AIUI) never the intent.
Rather, backward compatibility was critically examined for whether it
was justified in Python 3.

> why not enforce the four space rule?

Guido has used his time machine to answer your question a few years ago
<URL:http://www.artima.com/weblogs/viewpost.jsp?thread=101968>. (Be sure
to read the discussion in the comments on the article.)

> At least that way, when I get python code from somebody else, I would
> know what I am looking at, without having to do a hex dump, or
> something.

Any text editor that is good for programming (yes, I'm aware this is
perilously close to a ?no true Scotsman? fallacy) will have an option
to visibly differentiate whitespace characters, for exactly the reason
you point out.

-- 
 \           ?Special cocktails for the ladies with nuts.? ?bar, Tokyo |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From ben+python at benfinney.id.au  Fri Jul 10 19:37:53 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 11 Jul 2009 09:37:53 +1000
Subject: 2.4 VS 3.1 for simple print
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
Message-ID: <87hbxkm7n2.fsf@benfinney.id.au>

"earthlink" <noen> writes:

> Why does 
> 
> print "GarbageCollector: collected %d objects." % (gc.collect())
> 
> work in 2.4 but not in 3.1?

For this and other differences introduced in the Python 3.x series, see
<URL:http://www.python.org/dev/peps/pep-3100/>.

-- 
 \     ?Please do not feed the animals. If you have any suitable food, |
  `\                     give it to the guard on duty.? ?zoo, Budapest |
_o__)                                                                  |
Ben Finney


From tjreedy at udel.edu  Fri Jul 10 19:48:58 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 10 Jul 2009 19:48:58 -0400
Subject: tough-to-explain Python
In-Reply-To: <4a57aa70@news.x-privat.org>
References: <h309ot$bii$1@reader1.panix.com>	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>	<h3234l$aod$1@reader1.panix.com>	<mailman.2839.1247060874.8015.python-list@python.org>	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>	<00720d76$0$9710$c3e8da3@news.astraweb.com>	<mailman.2931.1247195266.8015.python-list@python.org>	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>	<mailman.2983.1247257646.8015.python-list@python.org>
	<4a57aa70@news.x-privat.org>
Message-ID: <h38k19$hsn$1@ger.gmane.org>

I V wrote:
> On Fri, 10 Jul 2009 16:27:12 -0400, Terry Reedy wrote:
>> a bug, bug a limitation due to using limited-range numbers. If one uses
>> residue classes instead of integers, and makes no adjustment, I consider
>> it wrong to blame Bentley.
> 
> But it was Bentley himself who used the C int type, so it hardly seems 
> unreasonable to blame him.

The original program that he verified was in pseudocode equivalent to 
the following (not tested) Python. The odd spec is due to Bentley using 
1-based arrays. From the 1986 book Programming Pearls

def binsearch(x, t):
    "If t is in sorted x[1:n], return its index; otherwise 0"
    #
    L,U = 1, len(x)-1
    while True:
       if L > U: return 0
       m = (L+U)/2
       if   x[m] <  t: L = m+1
       elif x[m] == t: return m
       elif x[m] >  t: U = m-1

He then translated into an unspecified dialect of BASIC, but it is 
consistent with Microsoft GW-BASIC. If so, L and U were float variables, 
while the largest possible array size for x was 32767. So as near as I 
can tell with that dialect, there was no possible problem with L+U 
overflowing or wrapping. Other dialects, I am not sure.

So I revise my statement to "I consider it wrong to blame the Bentley 
that wrote the original program" ;-).

If he later translated to C and fell into the residue class trap, then 
that reinforces my contention that using residue classes as ints is 
error prone.

Terry Jan Reedy



From r1chardj0n3s at gmail.com  Fri Jul 10 19:52:18 2009
From: r1chardj0n3s at gmail.com (Richard Jones)
Date: Sat, 11 Jul 2009 09:52:18 +1000
Subject: Announcing the 9th Pyweek game programming challenge!
Message-ID: <7CFED2D8-4C06-4E6F-B25D-C39A510C7686@gmail.com>

The date for the ninth PyWeek challenge has been set:

   Sunday 30th August to Sunday 6th September (00:00UTC to 00:00UTC)


The PyWeek challenge invites entrants to write a game in one week from
scratch either as an individual or in a team. Entries must be developed
in Python, during the challenge, and must incorporate some theme chosen
at the start of the challenge.


REGISTRATION IS NOT YET OPEN --

Registration will open one month before the start date. See the
competition timetable and rules:

    http://www.pyweek.org/9/


PLANNING FOR THE CHALLENGE --

Make sure you have working versions of the libraries you're going to  
use.
The rules page has a list of libraries and other resources.

Make sure you can build packages to submit as your final submission (if
you're going to use py2exe, make sure you know how to use it and that it
works).

If you don't have access to Linux, Windows or a Mac to test on, contact
friends, family or other competitors to find someone who is able to test
for you.



From ben+python at benfinney.id.au  Fri Jul 10 19:55:10 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 11 Jul 2009 09:55:10 +1000
Subject: Email provider recommendations for those tired of mangled messages
	(was: subprocess + python-daemon - bug/problem?)
References: <699d22bd-e912-4ea3-92b0-c352a64611fb@n11g2000yqb.googlegroups.com>
	<828acd8d-a9bd-4506-b695-e537af4587d8@l31g2000yqb.googlegroups.com>
	<873a94ojvi.fsf@benfinney.id.au>
Message-ID: <87d488m6u9.fsf_-_@benfinney.id.au>

Ben Finney <ben+python at benfinney.id.au> writes:

> Here it is without the unwanted extra line-wrapping that seems to
> plague all Google Mail users (seriously, folks: get a real mail
> provider that won't mangle your messages)

I've been asked off-list whether I have any suggestions for those who
want a better email provider. Handling email (transport and mailbox
services) is certainly a service that's worth getting someone else to
handle, provided you can trust they'll do so reliably and well. For me,
?well? includes ?don't mangle my messages?.

My personal solution to this is to manage my own email server machine,
but that's an ongoing investment of time that is not something I would
recommend to everyone.

Nancy McGough maintained (past tense? present tense?) a comprehensive
index <URL:http://www.ii.com/internet/messaging/imap/isps/#providers> of
email service providers with IMAP access, hence allowing you to use
whatever IMAP mail client you like to communicate with your mailboxes
remotely. There are feature lists and price indications for each
provider.

Several of my colleagues swear by Tuffmail <URL:http://tuffmail.com/> as
providing excellent uptime, fine control filtering, responsive service,
flexible customisation, and good overall value.

-- 
 \        ?Visitors are expected to complain at the office between the |
  `\                     hours of 9 and 11 a.m. daily.? ?hotel, Athens |
_o__)                                                                  |
Ben Finney


From nagle at animats.com  Fri Jul 10 20:02:19 2009
From: nagle at animats.com (John Nagle)
Date: Fri, 10 Jul 2009 17:02:19 -0700
Subject: tough-to-explain Python
In-Reply-To: <a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<a6d26a8b-2773-4f85-8d70-2cbe63fbb4eb@26g2000yqk.googlegroups.com>
Message-ID: <4a57d630$0$1646$742ec2ed@news.sonic.net>

Bearophile wrote:
> kj, as Piet van Oostrum as said, that's the difference between mutable
> an immutable. It comes from the procedural nature of Python, and
> probably an explanation of such topic can't be avoided if you want to
> learn/teach Python.

     The problem with Python's mutable/immutable distinction is that
it's not very visible.  In a language with no declarations, no named
constants, and no parameter attributes like "value", "in", "out", or
"const", it's not at all obvious which functions can modify what.
Which is usually the place where this causes a problem.

     The classic, of course, is

def additemtolist(item, lst = []) :
     lst.append(item)
     return(lst)

lista = additemtolist(1)
listb = additemtolist(2)
print(listb)

The general problem is inherent in Python's design.  This particular problem,
though, results in the occasional suggestion that parameters shouldn't
be allowed to have mutable defaults.

				John Nagle


From python.list at tim.thechases.com  Fri Jul 10 20:10:03 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 10 Jul 2009 19:10:03 -0500
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty"
	exception
In-Reply-To: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>
References: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>
Message-ID: <4A57D85B.8040305@tim.thechases.com>

>      shutil.rmtree(filename)
>    File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
>      onerror(os.rmdir, path, sys.exc_info())
>    File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
>      os.rmdir(path)
> OSError: [Errno 39] Directory not empty: /path/to/my/dir
> 
> According to the documentation, shutil.rmtree should not care about  
> directory being not empty.

This sounds suspiciously like a permission issue.  rmtree() 
*should* walk the tree removing items *if it can*.  If a file 
can't be deleted, it treats it as an error.  rmtree() takes 
parameters for ignore_errors and an onerror callback function, so 
you can catch these error conditions.

-tkc




From liukis at usc.edu  Fri Jul 10 20:30:56 2009
From: liukis at usc.edu (Maria Liukis)
Date: Fri, 10 Jul 2009 17:30:56 -0700
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty"
	exception
In-Reply-To: <4A57D85B.8040305@tim.thechases.com>
References: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu>
	<4A57D85B.8040305@tim.thechases.com>
Message-ID: <A7154223-8964-431D-A90D-EE37706383A3@usc.edu>

Thanks for pointing out the parameters for ignore_errors and an  
onerror callback function.

I have been running this code for more than an year, and this is the  
very first time I see the problem. We switched to the NFS mounted  
storage though, but there is nothing unusual logged by the system in  
the /var/log/messages.

I checked the permissions - the directory is still there and has  
exactly the same permissions as other successfully copied and removed  
directories (the very same process creates the directory and later  
removes it). The directory is empty though - so the process removed  
all the entries in it, then some kind of an error occured that  
triggered the exception.

There are lots of similar directories that the process creates and  
removes, but only one of them raised an exception.

Thanks,
Masha
--------------------
liukis at usc.edu



On Jul 10, 2009, at 5:10 PM, Tim Chase wrote:

>>      shutil.rmtree(filename)
>>    File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
>>      onerror(os.rmdir, path, sys.exc_info())
>>    File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
>>      os.rmdir(path)
>> OSError: [Errno 39] Directory not empty: /path/to/my/dir
>> According to the documentation, shutil.rmtree should not care  
>> about  directory being not empty.
>
> This sounds suspiciously like a permission issue.  rmtree()  
> *should* walk the tree removing items *if it can*.  If a file can't  
> be deleted, it treats it as an error.  rmtree() takes parameters  
> for ignore_errors and an onerror callback function, so you can  
> catch these error conditions.
>
> -tkc
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090710/39b997aa/attachment-0001.html>

From davea at ieee.org  Fri Jul 10 20:44:48 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 10 Jul 2009 20:44:48 -0400
Subject: AP -- MeAmI.org Paces Google
In-Reply-To: <h38f6t01fj2@news7.newsguy.com>
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>	<h36agp02ste@news7.newsguy.com>	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<h38f6t01fj2@news7.newsguy.com>
Message-ID: <4A57E080.20008@ieee.org>



David Bernier wrote:
>> <snip>
>>
>> Good day,
>>
>> Professor X
>
> This is what there is at the bottom of page 3:
>
> << Conclusion: Binary revisions are allowed given the above formulas. >>
>
> So I don't understand the proposed solution for the "P = NP"
> problem.
>
> David Bernier
>
>
"Professor X" is yet another alias for the hoaxter who started this 
thread, and presumably who created the website.




From benjamin.kaplan at case.edu  Fri Jul 10 21:25:19 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Fri, 10 Jul 2009 21:25:19 -0400
Subject: main in Python
In-Reply-To: <159869.41728.qm@web63104.mail.re1.yahoo.com>
References: <159869.41728.qm@web63104.mail.re1.yahoo.com>
Message-ID: <ec96e1390907101825v37dbfdc9qbef6d8da7595a70d@mail.gmail.com>

On Fri, Jul 10, 2009 at 5:52 PM, Tim<timlee126 at yahoo.com> wrote:
>
> Hi,
> I learned that a Python script is written in this way:
> def main():
> ? ?...
> if __name__ == "__main__":
> ? ?main()
>
> Today, when I read a script, I found it has a different way:
>
> def main():
> ? ?...
>
> main()
>
> It can run as well. Can someone explain why and the rules that Python scripts get run?
>


You're thinking like a C or Java programmer. Python scripts are just
that - scripts. They aren't compiled with a main() method for an entry
point- it's interpreted. When you run a python script, everything that
isn't indented is run, from top to bottom, in order. So for instance,
when the interpreter sees the line
def main() :
   pass
it creates a function called main. If you were to have the statement
x= 5
the value 5 would be assigned to x at that time. There are two ways to
execute these scripts- by running them directly and by importing them
into another module. The second way, with the main method, the script
will be run any time it is imported. The first relies on the fact that
any module run as a script has a __name__ attribute of "__main__"
(usually it's the name of the module). The first program acts more
like the C code would- the "main" part of it will only be run if that
script is executed.


> Thanks and regards,
> Tim
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From laurentluce49 at yahoo.com  Fri Jul 10 21:52:24 2009
From: laurentluce49 at yahoo.com (Laurent Luce)
Date: Fri, 10 Jul 2009 18:52:24 -0700 (PDT)
Subject: windows explorer integration
Message-ID: <44278.3184.qm@web54207.mail.re2.yahoo.com>


Hello,

Do you know if it is possible to write a plugin for windows explorer using win32 module ?

The idea is to modify the way the folders/files are displayed in the explorer window and also to provide some controls.

Laurent



From ryankaskel at gmail.com  Fri Jul 10 21:57:43 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Fri, 10 Jul 2009 18:57:43 -0700 (PDT)
Subject: Addind imports to a class namespace
Message-ID: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>

Greetings,

In order to avoid circular imports, I have a class that I want to
improve upon:

Class GenerateMenuXhtml(threading.Thread):
    """
    Subclasses a threading.Thread class to generate a menu's XHTML in
a separate
    thread. All Link objects that have this menu associated with it
are gathered
    and combined in an XHTML unordered list.

    If the sender is of type Link, then all menus associated with that
link are
    iterated through and rebuilt.
    """
    def __init__(self, instance):
        from asqcom.apps.staticpages.models import Menu, Link
        self.Link = Link
        self.Menu = Menu

As you can see I just expose these imports by attaching them to
members of the class. There must be "prettier" option though where I
can just add these imoprts to the class's namespace so all methods of
any instance will have access to the imported modules.

How would I go about doing this? How can I access the namespace of any
class? Through Class.__dict__?

Thanks,
Ryan



From greg at cosc.canterbury.ac.nz  Fri Jul 10 22:25:11 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sat, 11 Jul 2009 14:25:11 +1200
Subject: language analysis to enforce code standards
In-Reply-To: <h37mdh$rfm$1@panix3.panix.com>
References: <mailman.9989.1246930194.8014.python-list@python.org>
	<mailman.2927.1247192026.8015.python-list@python.org>
	<pan.2009.07.10.02.42.04@REMOVE.THIS.cybersource.com.au>
	<mailman.2948.1247229186.8015.python-list@python.org>
	<h37mdh$rfm$1@panix3.panix.com>
Message-ID: <7bqbeiF1rue32U1@mid.individual.net>

Aahz wrote:

> Much simpler and *way* more efficient with a set:
> 
> if len(set(s)) < N:
>     print "Must have at least %s different characters" % N

Or you could do a dictionary lookup on the words.
I can just see the error message:

   "Your comment must include at least one verb,
   one noun, one non-cliched adjective and one
   Monty Python reference."

-- 
Greg


From aahz at pythoncraft.com  Fri Jul 10 23:34:25 2009
From: aahz at pythoncraft.com (Aahz)
Date: 10 Jul 2009 20:34:25 -0700
Subject: sys.exit() and PyRun_SimpleFileExFlags()
References: <mailman.2922.1247183197.8015.python-list@python.org>
Message-ID: <h39181$9hn$1@panix3.panix.com>

In article <mailman.2922.1247183197.8015.python-list at python.org>,
=?ISO-8859-1?Q?Xavier_B=E9nech?=  <xavier.benech at t-immersion.com> wrote:
>
>There is a behaviour I do not understand of PyRun_SimpleFileExFlags(), 
>normally when it executes a python script containing a sys.exit(), it 
>results by ending the calling application.

If nobody responds on c.l.py, I suggest trying capi-sig.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From marty.musatov at gmail.com  Fri Jul 10 23:34:25 2009
From: marty.musatov at gmail.com (Musatov)
Date: Fri, 10 Jul 2009 20:34:25 -0700 (PDT)
Subject: AP -- MeAmI.org Paces Google
References: <fe9969b0-3c6a-49f7-8f38-0ed89dc9ad42@x6g2000prc.googlegroups.com>
	<h36agp02ste@news7.newsguy.com>
	<defacf35-6149-485a-8f03-15472d63de43@a39g2000pre.googlegroups.com>
	<h38f6t01fj2@news7.newsguy.com>
Message-ID: <f7013f86-ac00-496a-b875-13d67e689e7c@t21g2000yqi.googlegroups.com>

Martin Musatov wrote:
David Bernier wrote:
> scriber77 at yahoo.com wrote:
> [...]
>
> > community. But perhaps he is trying to see things a bit differently
> > and is just not getting the feedback he needs, so he is throwing
> > tantrums apparently across USENET.
> >
> > Like I said before, I am just trying to do right by this person who
> > contacted me, and seemed to be a decent person with a genuine interest
> > in mathematics. He was very respectful.
> >
> > Alas, I am at a loss on what specific feedback to give him on his
> > paper as though I am a professor of Mathematics, Computer Science is
> > not my specialty.
> >
> > I told him I would try to get him some feedback on the equations on
> > page 3.  Would any of you be so kind to help me?
> >
> > Here is the paper: http://MeAmI.org/pversusnp.pdf
> >
> > I do thank you for your time.
> >
> > Good day,
> >
> > Professor X
>
> This is what there is at the bottom of page 3:
>
> << Conclusion: Binary revisions are allowed given the above formulas. >>
>
> So I don't understand the proposed solution for the "P = NP"
> problem.
>
> David Bernier

P can be equal to N and not P when it is in brackets vs. parantheses.
The dots ib the equation in "P = [dots] <i>N</i> (dots) <i>P</i>. The
difference between the brackets and the paranthesis represents a
margin of time in computation. The dots present in the paper (I am not
able to render them here, but they are in the .pdf file) represent a
non-deterministic symbolic means of representing language. Thank you
for your respone.

The conclusion means traditional characters and symbols are not ideal
for binary computation.


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 11 00:01:03 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 11 Jul 2009 04:01:03 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<mGo3m.591$P5.76@nwrddc02.gnilink.net> <h2lb2a$9pt$1@reader1.panix.com>
	<zxr3m.613$P5.65@nwrddc02.gnilink.net> <h2nr4c$d91$2@reader1.panix.com>
	<mailman.2611.1246721197.8015.python-list@python.org>
	<h2o02i$3gs$1@reader1.panix.com> <7xzlbkti7z.fsf@ruckus.brouhaha.com>
	<h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<mailman.2962.1247243254.8015.python-list@python.org>
Message-ID: <0267ffdf$0$18215$c3e8da3@news.astraweb.com>

On Fri, 10 Jul 2009 12:27:25 -0400, Charles Yeomans wrote:

>> (3) assert is absolutely unsuitable for enforcing pre-conditions and
>> post-
>> conditions, unless such conditions are mere "guidelines", because
>> assert
>> can be switched off at runtime.
> 
> 
> Unless, of course, you want to switch off such checking at runtime, as
> you might when using a design-by-contract approach.

So is design-by-contract just another way of saying "let's hope the data 
is valid, because if it's not, we're screwed"?

Perhaps Python should have a new statement, `assume`, used just like 
`assert` except it never actually performs the test or raises an error.


-- 
Steven


From tjreedy at udel.edu  Sat Jul 11 01:04:45 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 11 Jul 2009 01:04:45 -0400
Subject: Clarity vs. code reuse/generality
In-Reply-To: <0267ffdf$0$18215$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>	<mGo3m.591$P5.76@nwrddc02.gnilink.net>
	<h2lb2a$9pt$1@reader1.panix.com>	<zxr3m.613$P5.65@nwrddc02.gnilink.net>
	<h2nr4c$d91$2@reader1.panix.com>	<mailman.2611.1246721197.8015.python-list@python.org>	<h2o02i$3gs$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com>	<h2ogli$n9p$2@reader1.panix.com>	<mailman.2700.1246895025.8015.python-list@python.org>	<h33k3d$2uu$1@reader1.panix.com>	<mailman.2872.1247126235.8015.python-list@python.org>	<pan.2009.07.10.02.28.04.344000@nowhere.com>	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>	<mailman.2962.1247243254.8015.python-list@python.org>
	<0267ffdf$0$18215$c3e8da3@news.astraweb.com>
Message-ID: <h396hc$hgp$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 10 Jul 2009 12:27:25 -0400, Charles Yeomans wrote:
> 
>>> (3) assert is absolutely unsuitable for enforcing pre-conditions and
>>> post-
>>> conditions, unless such conditions are mere "guidelines", because
>>> assert
>>> can be switched off at runtime.
>>
>> Unless, of course, you want to switch off such checking at runtime, as
>> you might when using a design-by-contract approach.
> 
> So is design-by-contract just another way of saying "let's hope the data 
> is valid, because if it's not, we're screwed"?
> 
> Perhaps Python should have a new statement, `assume`, used just like 
> `assert` except it never actually performs the test or raises an error.

The manual says quite clearly

"The simple form, assert expression, is equivalent to
if __debug__:
    if not expression: raise AssertionError"

It should be used when and only when one actually wants the double 
condition check, and not as an abbreviation of the second conditional only.

tjr





From haematopus at gmail.com  Sat Jul 11 01:52:40 2009
From: haematopus at gmail.com (oystercatcher)
Date: Fri, 10 Jul 2009 22:52:40 -0700 (PDT)
Subject: fedora 3.1 python install
Message-ID: <69d90aab-eee3-4fa3-8960-4548e4e706d7@h2g2000yqg.googlegroups.com>

had installed python 3.0. on fc11 x64
the only anomalies were a couple of tests failed during the make
test.  make altinstall was fine and have been using it for a simple
math exercise.

attempting to install python 3.1 the make test hangs at
test_httpservers and I had to kill the task after waiting quite
awhile.  now probably this is no big deal and I should just go ahead
and run the make altinstall but it would be nice to know a bit more
about what is going on here.

thanks


From nobody at nowhere.com  Sat Jul 11 02:24:02 2009
From: nobody at nowhere.com (Nobody)
Date: Sat, 11 Jul 2009 07:24:02 +0100
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
Message-ID: <pan.2009.07.11.06.24.02.406000@nowhere.com>

On Fri, 10 Jul 2009 09:23:54 +0000, garabik-news-2005-05 wrote:

>>> I would like to learn a way of changing the colour of a particular
>>> part of the output text. I've tried the following
> 
>> On Unix operating systems this would be done through the curses interface:
>> 
>> http://docs.python.org/library/curses.html
> 
> Or using ANSI colour codes:
> 
> colours = {
>             'none'       :    "",
>             'default'    :    "\033[0m",
>             'bold'       :    "\033[1m",

[snip]

>             # non-standard attributes, supported by some terminals 

This comment should have appeared immediately after "none" ;)

Hard-coding control/escape sequences is just lame. Use the curses modules
to obtain the correct sequences for the terminal.



From research at johnohagan.com  Sat Jul 11 02:30:24 2009
From: research at johnohagan.com (John O'Hagan)
Date: Sat, 11 Jul 2009 06:30:24 +0000
Subject: tough-to-explain Python
In-Reply-To: <001401ca014c$ca414d60$0d00a8c0@Hendrik>
References: <h309ot$bii$1@reader1.panix.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<001401ca014c$ca414d60$0d00a8c0@Hendrik>
Message-ID: <200907110630.24557.research@johnohagan.com>

On Fri, 10 Jul 2009, Hendrik van Rooyen wrote:
> "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
> >On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:

[...]

> >> Programming is not like any other human activity.
> >
> >In practice? In principle? Programming in principle is not the same as it
> >is performed in practice.
> >
> >But in either case, programming requires both the logical reasoning of
> >mathematics and the creativity of the arts. Funnily enough,
>
> I do not buy this arty creativity stuff. - or are you talking about
> making a website look pretty?
>
> >mathematicians will tell you that mathematics requires the same, and so
> >will the best artists. I think mathematicians, engineers, artists, even
> >great chefs, will pour scorn on your claim that programming is not like
> >any other human activity.
>
> So a chef is now an authority on programming?
>
> Programming is actually kind of different - almost everything else is
> just done, at the time that you do it.
>
> Programming is creating stuff that is completely useless until it is
> fed into something that uses it, to do something else, in conjuction
> with the thing it is fed into, at a later time.
>
> This is a highly significant difference, IMHO.

[...]

The drawings produced by an architect, the script of a play, the score of a 
piece of music, and the draft of a piece of legislation are all examples of 
other things which are "useless" until they are interpreted in some way. 

There are countless human activities which require a program, i.e. a conscious 
plan or strategy, formed at least partly by a creative process, and a computer 
program is just a special case of this. 

I use Python as a tool for writing music, but I find I need both logical 
reasoning and creativity to do either. In fact, I find programming very similar 
to writing music in a rigorous contrapuntal style, where each set of choices 
constrains each other, and there is a deep aesthetic satisfaction in getting 
it right.

Regards,

John




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090711/288080b1/attachment-0001.html>

From __peter__ at web.de  Sat Jul 11 02:51:48 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 11 Jul 2009 08:51:48 +0200
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
Message-ID: <h39cpr$o4u$01$1@news.t-online.com>

Ryan K wrote:

> In order to avoid circular imports, I have a class that I want to
> improve upon:
> 
> Class GenerateMenuXhtml(threading.Thread):
>     """
>     Subclasses a threading.Thread class to generate a menu's XHTML in
> a separate
>     thread. All Link objects that have this menu associated with it
> are gathered
>     and combined in an XHTML unordered list.
> 
>     If the sender is of type Link, then all menus associated with that
> link are
>     iterated through and rebuilt.
>     """
>     def __init__(self, instance):
>         from asqcom.apps.staticpages.models import Menu, Link
>         self.Link = Link
>         self.Menu = Menu
> 
> As you can see I just expose these imports by attaching them to
> members of the class. There must be "prettier" option though where I
> can just add these imoprts to the class's namespace so all methods of
> any instance will have access to the imported modules.
> 
> How would I go about doing this? How can I access the namespace of any
> class? Through Class.__dict__?

You can write either

class A(object):
    from some.module import Menu, Link

or 

class A(object):
    @classmethod
    do_imports(cls):
        from some.module import Menu, Link
        cls.Menu = Menu
        cls.Link = Link

A.do_imports()

to put the names into the class. The first form performs the import while 
the containing module is imported and therefore won't help with breaking 
circles. In the second form you have to defer the A.do_imports() method call 
until the import from some.module is safe.

But I still recommend that you have another look at your package 
organization to find a way to avoid circles.

Peter



From piet at cs.uu.nl  Sat Jul 11 03:54:19 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 11 Jul 2009 09:54:19 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2931.1247195266.8015.python-list@python.org>
	<pan.2009.07.10.03.41.42@REMOVE.THIS.cybersource.com.au>
	<mailman.2983.1247257646.8015.python-list@python.org>
	<4a57aa70@news.x-privat.org>
Message-ID: <m21von8xjo.fsf@cs.uu.nl>

>>>>> I V <ivlenin at gmail.com> (IV) wrote:

>IV> On Fri, 10 Jul 2009 16:27:12 -0400, Terry Reedy wrote:
>>> a bug, bug a limitation due to using limited-range numbers. If one uses
>>> residue classes instead of integers, and makes no adjustment, I consider
>>> it wrong to blame Bentley.

>IV> But it was Bentley himself who used the C int type, so it hardly seems 
>IV> unreasonable to blame him.

If you are on a 32-bit machine, and the array to be searched contains
ints, floats or doubles, the the array must be < 2^32 bytes in size, and
as each element is at least 4 bytes, the indices are less than 2^30, so
l+u < 2^31. Therefore there is no overflow at all. I think the Bentley
programs were formulated in terms of arrays of ints. So his
implementations were safe.

If you are on a 64-bit machine you shouldn't use int for the indices
anyway (supposing int is 32 bits) but longs and then the same reasoning
shows that there are no overflows. Only when you have an array of shorts
or bytes (chars) you get the problem.

In that case the alternative formulation l + (u-l)/2 is more
robust and therefore preferable.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From Iris-und-Thomas-Lehmann at T-Online.de  Sat Jul 11 04:12:27 2009
From: Iris-und-Thomas-Lehmann at T-Online.de (Thomas Lehmann)
Date: Sat, 11 Jul 2009 01:12:27 -0700 (PDT)
Subject: Tkinter only: table widget with canvas...
References: <mailman.10638.1247239202.8014.python-list@python.org> 
	<mailman.2990.1247265085.8015.python-list@python.org>
Message-ID: <5db86de3-d0a0-42c7-8924-7ba8948cfd99@32g2000yqj.googlegroups.com>

>
> There's a working app at http://cl1p.net/tkinter_table_headers/
>
> -John

Thank you for this example. However, one issue to that...
When resizing the window (vertical) then the header moves away
from the table. How can I avoid this with the grid? With "pack"
I now this...


From p.f.moore at gmail.com  Sat Jul 11 05:25:26 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Sat, 11 Jul 2009 10:25:26 +0100
Subject: windows explorer integration
In-Reply-To: <44278.3184.qm@web54207.mail.re2.yahoo.com>
References: <44278.3184.qm@web54207.mail.re2.yahoo.com>
Message-ID: <79990c6b0907110225p14dd718bv26a36e5b13d5e51@mail.gmail.com>

2009/7/11 Laurent Luce <laurentluce49 at yahoo.com>:
> Do you know if it is possible to write a plugin for windows explorer using win32 module ?

Yes, I believe it is. There are a number of Python projects (I believe
TortoiseHg is one) that do this sort of thing.

However, I don't know anything about how to do it - you should check
MSDN, the PyWin32 samples, and maybe something like TortoiseHg, for
sample code.

Paul.


From magobin at gmail.com  Sat Jul 11 06:39:25 2009
From: magobin at gmail.com (Alex)
Date: Sat, 11 Jul 2009 03:39:25 -0700 (PDT)
Subject: problem with keys combination!
References: <154882be-dfc0-486e-8dc9-1d6807f2c8c9@t13g2000yqt.googlegroups.com>
	<mailman.2986.1247259250.8015.python-list@python.org>
Message-ID: <dc7e6aad-f459-4760-93d0-3bb288afc5d1@a26g2000yqn.googlegroups.com>


> Blocking Ctrl-Alt-Del leaves the power switch or maybe the plug as the
> only way for the user to regain control. Why would you want to do that?

ONly for the reason that I explaine above...is for my little joke
application !
And I want disable all keys for about 30 seconds (time to erase
background)
I read about getasynckey() to intercept a key...but I don't know how
to change key pressed with another...maybe a solution ?

Alex


From gslindstrom at gmail.com  Sat Jul 11 07:10:17 2009
From: gslindstrom at gmail.com (gslindstrom)
Date: Sat, 11 Jul 2009 04:10:17 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <adbcd3fe-5468-4490-a7f1-1fdf359f0bb4@t33g2000yqe.googlegroups.com>

On Jul 10, 2:22?pm, walterbyrd <walterb... at iname.com> wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.
>
> Since backward compatibility is being thrown away anyway, why not
> enforce the four space rule?
>

There is a routine in the Scripts directory, reindent.py, that will
take your source file(s) and remove tabs, unify the indents to 4-
spaces, remove needless characters at the end of lines, etc.  IIRC, it
was written by Tim Peters.  We run all of our source files though
before checking them into svn.


--greg


From mail at microcorp.co.za  Sat Jul 11 08:01:25 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 14:01:25 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com><00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <000f01ca021f$5132b5c0$0d00a8c0@Hendrik>

"Steven D'Aprano" <steve at REMOVE-THIS-cyb.....ce.com.au> wrote:

>On Fri, 10 Jul 2009 12:54:21 +0200, Hendrik van Rooyen wrote:
>
>> "Steven D'Aprano" <steve at REMOVE-THIS-cy....e.com.au> wrote:
>> 
>>>On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
>>>
>>>>> persistent idea "out there" that programming is a very accessible
>>>>> skill, like cooking or gardening, anyone can do it, and even profit
>>>>> from it, monetarily or otherwise, etc., and to some extent I am
>>>> 
>>>> Programming is not like any other human activity.
>>>
>>>In practice? In principle? Programming in principle is not the same as
>>>it is performed in practice.
>>>
>>>But in either case, programming requires both the logical reasoning of
>>>mathematics and the creativity of the arts. Funnily enough,
>> 
>> I do not buy this arty creativity stuff. - or are you talking about
>> making a website look pretty?
>
>I must admit, it never crossed my mind that anyone here would claim that 
>there was no creativity involved in programming, that it was all a 
>mindless, algorithmic process capable of being done by a simple 
>mechanical device.

"Programming" is the step of going from the "design" to something
that tells the machine how to implement the design.

The creativity could, arguably, be in the "Design".
Not in the translation to python, or assembler.
No way.  That is just coding.

>
>This is certainly the accusation made against *bad* programmers -- that 
>they can't actually solve new, unique problems, but just apply recipes 
>they learned without any insight or intelligence. The sort of people who 
>program so poorly that "a trained monkey could do what they do".
>
>Do you really think that applies to good programmers too? If so, then a 
>good code generator should be able to replace any programmer. Is that 
>what you believe?
>

Should eventually be possible, with sufficient restrictions to start off.
UML wants to go this route...

But may my eyes be stopped and my bones be heaped with dust
ere I see the day...

>
 >
>>>mathematicians will tell you that mathematics requires the same, and so
>>>will the best artists. I think mathematicians, engineers, artists, even
>>>great chefs, will pour scorn on your claim that programming is not like
>>>any other human activity.
>> 
>> So a chef is now an authority on programming?
>
>Did I say that?

No.  I just read it like that to irritate you.

>
>Chefs are authorities on OTHER HUMAN ACTIVITIES.
>
>
>
>> Programming is actually kind of different - almost everything else is
>> just done, at the time that you do it.
>> 
>> Programming is creating stuff that is completely useless until it is fed
>> into something that uses it, to do something else, in conjuction with
>> the thing it is fed into, at a later time.
>
>Somebody should teach Hendrik that human beings have been creating TOOLS 
>for hundreds of thousands of years. People have been creating tools to 
>build tools for thousands of years. Software is just more of the same.

I disagree - I actually own some machine tools, so I am a little
bit acquainted with what they can do, and it is not at all like computing
at any level I can think of - they are merely extensions of the hand, making
the transformation of materials more accurate and faster.

The line only becomes blurred when a processor is added, and a STORED
PROGRAM is brought into the equation.

>
>Even *soup stock* fits the same profile as what Hendrik claims is almost 
>unique to programming. On its own, soup stock is totally useless. But you 
>make it, now, so you can you feed it into something else later on.
>
>Or instant coffee.
>
>No, Henrik, if that's the best you can do, it's not very good. It is 
>rather sad, but also hilarious, that the most different thing you have 
>noticed about software is that it's just like instant coffee.
>

You have a wonderful ability to grab hold of part of a definition
and to ignore the rest, just like I can misread what you write.

Coffee and soup stay coffee and soup on re hydration.  Mixing it
in with something else is not at all the same - it does not "DO" anything
else in conjunction with the thing it is fed into - how is that like 
programming, and executing a program?

I am sorry if you are confusing the drinking of coffee,
which is an ancilliary activity to programming, with the
actual programming itself.

>
>
>> This is a highly significant difference, IMHO.
>
>
>>>[...]
>>>> He talks about how "when all is said and done, the only thing
>>>> computers can do for us is to manipulate symbols and produce results
>>>> of such manipulations" and he emphasises the "uninterpreted" nature of
>>>> mechanical symbol manipulation, i.e. that the machine is doing it
>>>> mindlessly.
>>>
>>>"Manipulate symbols" is so abstract as to be pointless. By that
>>>reasoning, I can build a "computer" consisting of a box open at the top.
>>>I represent a symbol by an object (say, a helium-filled balloon, or a
>>>stone), instead of a pattern of bits. I manipulate the symbol by holding
>>>the object over the box and letting go. If it flies up into the sky,
>>>that represents the symbol "Love is War", if it falls into the box, it
>>>represents the symbol "Strength is Blue", and if it just floats there,
>>>it represents "Cheddar Cheese". This is a deterministic, analog computer
>>>which manipulates symbols. Great.
>>>
>>>And utterly, utterly useless. So what is my computer lacking that real
>>>computers have? When you have answered that question, you'll see why
>>>Dijkstra's claim is under-specified.
>>>
>>>
>> So if computers do not manipulate symbols, what is it that they do?
>
>Did I say they don't manipulate symbols?

No you wanted someone to tell you how to make your
box machine useful, and that was too difficult, so I went this way.

>
>
>> They
>> sure cannot think,
>> or drink,
>> or reason,
>
>They can't reason? Then what are they doing when they manipulate symbols?

They simply manipulate symbols.
They really do.
There is no reasoning involved.

Any reasoning that is done, was done in the mind of the human who designed
the system, and the the machine simply manipulates the implementation of
the abstract symbols, following the implementation of the abstract rules that
were laid down.  No reasoning at run time at all.

Lots of decision making though - and it is this ability to do this now, and
something else later, that tricks the casual observer into thinking that there
is somebody at home - a reasoning ghost in the machine.

>
>Yet again, it didn't even cross my mind that somebody would make this 
>claim. My entire point is that it's not enough to just "manipulate 
>symbols", you have to manipulate symbols the correct way, following laws 
>of logic, so that the computer can *mindlessly* reason.

No. 

There is no requirement for dragging in things like "the laws of logic"
or any arbitrarily chosen subset.  You can build a machine to do
essentially "anything" - and people like Turing and his ilk have
spent a lot of skull sweat to try to define what is "general purpose",
to enable you to do "anything"

>
>
>> or almost any verb you can think of.
>
>If you're going to take that argument, then I'll remind you that there 
>are no symbols inside a computer. There are only bits. And in fact, there 
>aren't even any bits -- there are only analog voltages, and analog 
>magnetic fields.
>

Duh - sorry to hear that - I have only been doing digital electronics
now for more years than I care to remember - but maybe there
is a difference in how you define "analogue". - maybe something like:
"if I can measure it with a multimeter, it is an analogue signal, because
a multimeter is capable of measuring analogue signals"  - a bit fallacious.

More seriously,  I again differ on the symbol bit - I am, right now, 
working on a little processor that mindlessly does I/O, by manipulating 
bits from one representation to another.  In this case, the symbols
and the bits are mostly identical - but please do not try to tell
me that there are no symbols inside the little processors' 
memory - I know they are there, because I have arranged for 
them to be put there, via an RS-232 feed.

And my stored program actually arranges for the incoming symbols
to do things like activating output relays, and changes on input lines
actually cause other symbols to be transmitted out of the RS-232
port.  The whole thing is simply rotten with symbology - in fact all
it does, is manipulating the implementation of the abstract symbols 
in my mind.
It does so mindlessly.
This specific thing is so simple, that it hardly uses the
"logical ability" of the processor.  And please remember that
for a function with two input bits and a single output bit, there can 
at most be eight possible outcomes, not all of which are useful, for
some definition of useful.  But they exist, and you can use them, if 
you want. And you do not even have to be consistent, if you do not
want to be, or if it is convenient not to be.

I think it is this horrendous freedom that Dijkstra was talking about
when he was referring to the "power beyond your wildest dreams",
or some such.

>
>> "Manipulating symbols" is actually an elegant definition. Try coming up
>> with a better one and you will see.
>
>As I said above, it's not enough to just manipulate symbols. Here's a set 
>of rules to manipulate symbols:
>
>X => 0
>
>or in English, "Any symbol becomes the zero symbol".
>
>That's symbol manipulation. Utterly useless. This is why it's not enough 
>to just manipulate symbols, you have to manipulate them THE RIGHT WAY.
>

No.
There is no RIGHT WAY.
Really.
There are only ways that are useful, or convenient.

In my little processor, I can cause any result
to occur, and the rules can be as silly as your
example - if it is useful for you, under some
circumstances, for all symbols to become the
symbol for zero, then go for it - The point is that 
there is nothing prohibiting it to be adopted as a
rule for a machine to implement.  

/dev/null anyone?

- Hendrik





From mail at microcorp.co.za  Sat Jul 11 08:14:55 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 14:14:55 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<c40ec96a-5494-483c-a461-676c8bb29876@x3g2000yqa.googlegroups.com>
Message-ID: <001001ca0221$33a04c00$0d00a8c0@Hendrik>

"pdpi" <pd....iro at gmail.com> wrote;

>I've always found cooking an apt metaphor for programming.

No this is wrong.

Writing a recipe or a cookbook is like programming.

Cooking, following a recipe, is like running a program.

- Hendrik





From jjposner at optimum.net  Sat Jul 11 09:31:58 2009
From: jjposner at optimum.net (John Posner)
Date: Sat, 11 Jul 2009 09:31:58 -0400
Subject: Tkinter only: table widget with canvas...
In-Reply-To: <mailman.54.1247306403.18041.python-list@python.org>
References: <mailman.54.1247306403.18041.python-list@python.org>
Message-ID: <4A58944E.2030009@optimum.net>


>> There's a working app at http://cl1p.net/tkinter_table_headers/
> Thank you for this example. However, one issue to that...
> When resizing the window (vertical) then the header moves away
> from the table. How can I avoid this with the grid? With "pack"
> I now this...

Oops ... packing can be tricky. Try these modifications:

   header_frm.pack(side=TOP, anchor=W, expand=False)
    ...
   table_frm.pack(side=TOP, expand=True, fill=BOTH)

You also might try constraining the top-level (root) window, using these 
methods:

  rt.geometry(XXX, YYY)
  rt.resizable(False, True)

-John





From ryankaskel at gmail.com  Sat Jul 11 09:55:34 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Sat, 11 Jul 2009 06:55:34 -0700 (PDT)
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
Message-ID: <89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>

Thanks for your help Peter.

I'm thinking that perhaps this isn't a circular import and that I
don't understand importing. Here is a better explanation of my case (I
am using Django):

I have file x.py that declares classes A, B, C.

There is also a file y.py that contains two methods T, U and the class
that we are talking about above.

x.py uses a dispatcher system to connect a signal to methods T and U
in y.py so it does: from y import T, U.

y.py needs to use classes A, B, C which is basically Menu and Link
(and some other class) above so I am thinking that if in y.py I have
from x import A, B, C that will cause a circular import?

Is this not correct and if it isn't can you explain why? Does using
from ... import X, Y, Z, i.e. explicit imports avoid this problem or
does it exacerbate it?

Thanks,
Ryan


From XX.XmcX at XX.XmclaveauX.com  Sat Jul 11 10:13:20 2009
From: XX.XmcX at XX.XmclaveauX.com (MC)
Date: Sat, 11 Jul 2009 16:13:20 +0200
Subject: windows explorer integration
References: <mailman.2998.1247277549.8015.python-list@python.org>
Message-ID: <mn.5bcd7d9798964fe2.46195@XX.XmclaveauX.com>

Hi!

Possible!  With Pywin32.
I see two ways:
  - add a "toolBar" ; see the exemple for Internet-Explorer (it run for 
both, IE & explorer)
  - add an entry in the context menu (right click)

@-salutations
--
Michel Claveau

-- 
@-salutations

Michel Claveau




From __peter__ at web.de  Sat Jul 11 10:39:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 11 Jul 2009 16:39:13 +0200
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
Message-ID: <h3a865$tij$03$1@news.t-online.com>

Ryan K wrote:

> I'm thinking that perhaps this isn't a circular import and that I
> don't understand importing. Here is a better explanation of my case (I
> am using Django):
> 
> I have file x.py that declares classes A, B, C.

Classes in Python are executable code, just like import-statements. That's 
why there is no Python equivalent to forward declarations in other 
languages; every name has to be known at the point where it occurs in the 
module.
 
> There is also a file y.py that contains two methods T, U and the class
> that we are talking about above.
> 
> x.py uses a dispatcher system to connect a signal to methods T and U
> in y.py so it does: from y import T, U.
> 
> y.py needs to use classes A, B, C which is basically Menu and Link
> (and some other class) above so I am thinking that if in y.py I have
> from x import A, B, C that will cause a circular import?

Yes. Having x import y and y import x creates a cycle. If you cannot avoid 
this by moving to a simpler design you can always introduce a third module z
that imports x and y, and then explicitly resolves the circular references.
 
> Is this not correct and if it isn't can you explain why? Does using
> from ... import X, Y, Z, i.e. explicit imports avoid this problem or
> does it exacerbate it?

It has no effect.

from module import X

is equivalent to

import module
X = module.X
del module # just the name, not the module itself

Peter



From mail at microcorp.co.za  Sat Jul 11 11:10:04 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 17:10:04 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><00720d76$0$9710$c3e8da3@news.astraweb.com><001401ca014c$ca414d60$0d00a8c0@Hendrik>
	<200907110630.24557.research@johnohagan.com>
Message-ID: <007701ca0240$77f9c2e0$0d00a8c0@Hendrik>

 John O'Hagan  wrote:


>The drawings produced by an architect, the script of a play, the score of a
piece of music, and the draft of a piece of >legislation are all examples of
other things which are "useless" until they are interpreted in some way.

Granted.
But...

>There are countless human activities which require a program, i.e. a conscious
plan or strategy, formed at least partly >by a creative process, and a computer
program is just a special case of this.

The difference is that for a piece of music, or a recipe for
"bobotie", there is room for artistry also in the performance
or preparation.

If the piece of music is reduced to a scroll with holes in it
and played on a pianola, then nobody in his right mind
would call the mechanically produced sounds
"a great performance".

And this is the essential difference that sets programming apart from
cookbook writing or drawing architectural plans - the one thing that
makes the real difference is the mindlessness of the performer.

(maybe I should conceed that writing legislation is a form of
programming, as the constabulary does not have a reputation
for anything other than a plodding consistency)

>I use Python as a tool for writing music, but I find I need both logical
reasoning and creativity to do either. In fact, I >find programming very similar
to writing music in a rigorous contrapuntal style, where each set of choices
constrains >each other, and there is a deep aesthetic satisfaction in getting it
right.

Getting it right has to do with the design, not the programming -

Have you ever struggled to get something right, and then one day
you take a different tack, and suddenly it is as if you cannot do
anything wrong - everything just falls into place? - That is the time
that you get the good feeling.

The difference between the one and the other is the difference
between bad or indifferent design and good design.  When you
have a good design, the rest follows.  If your design is crud, no
matter what you do, you struggle and nothing comes out just
right, despite heroic effort.

Now this stuff is easy to talk about, and immensely difficult to
do - it takes experience, some skill, some cunning, and a
willingness to experiment in an egoless fashion, amongst other
things.

And then the stupid compiler completely screws up your intent...
:-)

- Hendrik





From darcy at druid.net  Sat Jul 11 11:22:42 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Sat, 11 Jul 2009 11:22:42 -0400
Subject: tough-to-explain Python
In-Reply-To: <000f01ca021f$5132b5c0$0d00a8c0@Hendrik>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<mailman.2944.1247223458.8015.python-list@python.org>
	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<000f01ca021f$5132b5c0$0d00a8c0@Hendrik>
Message-ID: <20090711112242.ec01ae8b.darcy@druid.net>

On Sat, 11 Jul 2009 14:01:25 +0200
"Hendrik van Rooyen" <mail at microcorp.co.za> wrote:
> "Programming" is the step of going from the "design" to something
> that tells the machine how to implement the design.
> 
> The creativity could, arguably, be in the "Design".
> Not in the translation to python, or assembler.
> No way.  That is just coding.

One might also argue that divorcing the design from the code is the
problem in a lot of legacy code.  See Agile Programming methods.  Now
you could say that there is a design step still in talking to the
client and making a plan in your head or in some notes but that's like
saying that Michelangelo was done creating after discussing the Sistine
Chapel with Pope Sixtus and that the rest was just a house painting job.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From mail at microcorp.co.za  Sat Jul 11 11:58:32 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 11 Jul 2009 17:58:32 +0200
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com><00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org><007318de$0$9710$c3e8da3@news.astraweb.com><000f01ca021f$5132b5c0$0d00a8c0@Hendrik>
	<20090711112242.ec01ae8b.darcy@druid.net>
Message-ID: <007801ca0240$78a01500$0d00a8c0@Hendrik>

"D'Arcy J.M. Cain" <d.. at druid.net>

> One might also argue that divorcing the design from the code is the
> problem in a lot of legacy code.  See Agile Programming methods.  Now
> you could say that there is a design step still in talking to the
> client and making a plan in your head or in some notes but that's like
> saying that Michelangelo was done creating after discussing the Sistine
> Chapel with Pope Sixtus and that the rest was just a house painting job.

How do you know that it was not exactly like that - he did, after all, take
a much longer time than expected to complete the job - just like a house
painter that gets paid by the hour. :-)

It is also unreasonable to assume the opposite fallacy - that he was in
a creative frenzy from the start to the time at the end when he was
cleaning his brush after applying the last spot of paint.

But it is a valid point - it is often difficult to draw the line between the
design and the implementation - and one of the reasons that we all
like to program in python, is that it is almost a language that is a
design language that can also be run directly.  - I have lately been doing
stuff like writing rough prototypes using python syntax to serve as
designs for some of the assembler thingies I do. If you muck around
a bit at the lower level, you will also be more aware of the dichotomy
between the design and the implementation - in python, it is not obvious
at all.  In assembler, it is glaring.  But in either place, if you get it wrong,
you suffer. -  your programs cripple along, or they hardly do what
you thought they would, and they bear no relationship with what the
customer wanted.

- Hendrik





From 2.b7e15163 at googlemail.com  Sat Jul 11 13:33:10 2009
From: 2.b7e15163 at googlemail.com (Henry 'Pi' James)
Date: Sat, 11 Jul 2009 10:33:10 -0700 (PDT)
Subject: asyncore's lack of sendto(), recvfrom()
Message-ID: <3cbf56cf-1362-44af-9d9f-4f5f2f298c0a@a26g2000yqn.googlegroups.com>

Is there any good reason why sendto() and recvfrom() aren't wrapped by
asyncore? Obviously, recvfrom() cannot be replaced by recv(), but even
sendto() cannot be replace by connect() and send(), either:

I'm writing a traceroute module, and I found out that under the
current firewall configuration of my OS, sending an ICMP packet via
sendto() doesn't trigger a connection confirmation (the packet is
silently and successfully sent), while connect() does (the firewall
reports an attempted UDP connection, I'm sure why). I know Python
merely wraps send() and sendto() from <sys/socket.h> of the OS,
obviously there are some important subtle differences between the two.

Now, if I'd want to add sendto() and recvfrom() to asyncore, would it
be sufficient to simply copying its send() and recv() wrapper
functions and change the names and arguments, or are there more
modifications required?


From mondi at cs.unibo.it  Sat Jul 11 13:55:25 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Sat, 11 Jul 2009 17:55:25 +0000
Subject: hoe to build a patched socketmodule.c
In-Reply-To: <BbWdnQyDurB8MsrXnZ2dnUVZ_j6dnZ2d@pdx.net>
References: <h34dsu$a4j$1@lec.cs.unibo.it>
	<mailman.2929.1247192119.8015.python-list@python.org>
	<h37eat$qmm$1@lec.cs.unibo.it>
	<BbWdnQyDurB8MsrXnZ2dnUVZ_j6dnZ2d@pdx.net>
Message-ID: <h3ac1a$8j6$1@lec.cs.unibo.it>

Scott David Daniels wrote:
> jacopo mondi wrote:
>> Roger Binns wrote:
>>> jacopo mondi wrote:
>>>> Hi all, I need to patch socketmodule.c (the _socket module) in order to
>>>> add support to an experimental socket family.
>>> You may find it considerably easier to use ctypes since that will avoid
>>> the need for any patching.  You'll also be able to control how read and
>>> write are done (eg read vs recvfrom vs recvmsg vs readv).  You can use
>>> os.fdopen to convert your raw file descriptor into a Python file object
>>> if appropriate.
> 
> The typical Python way of dealing with this is an additional module, not
> a modified module placed back in the library.  So, take the sources and
> edit, but change the module name.  Even better is figure out how to
> use _socket.pyd, to create a smaller _socketexpmodule.c and use that.
> 
> --Scott David Daniels
> Scott.Daniels at Acm.Org
Thanks a lot Scott.
If I'll write a new module, with a new name, based on socketmodule.c I
will not be able to ditribuite the source code and make users compile it
using distutils, instead I have to compile it using the whole python
build system (changing setup.py in python sources to let it know about
my new module) and distribuite the compiled .so with a script to install
it, I suppose. Anyway, that's not too bad...
Reusing _socket.so, or the main wrapper socket.pyc I think is not
possible, because I need to modify low level functions that are not exposed

thanks again
	jacopo


From davea at ieee.org  Sat Jul 11 13:56:04 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 11 Jul 2009 13:56:04 -0400
Subject: Addind imports to a class namespace
In-Reply-To: <89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
Message-ID: <4A58D234.4050607@ieee.org>

Ryan K wrote:
> Thanks for your help Peter.
>
> I'm thinking that perhaps this isn't a circular import and that I
> don't understand importing. Here is a better explanation of my case (I
> am using Django):
>
> I have file x.py that declares classes A, B, C.
>
> There is also a file y.py that contains two methods T, U and the class
> that we are talking about above.
>
> x.py uses a dispatcher system to connect a signal to methods T and U
> in y.py so it does: from y import T, U.
>
> y.py needs to use classes A, B, C which is basically Menu and Link
> (and some other class) above so I am thinking that if in y.py I have
> from x import A, B, C that will cause a circular import?
>
> Is this not correct and if it isn't can you explain why? Does using
> from ... import X, Y, Z, i.e. explicit imports avoid this problem or
> does it exacerbate it?
>
> Thanks,
> Ryan
>
>   
You indeed have described a circular import.  In this case, a mutual 
dependency exists between x.py and y.py.  This can and nearly always 
should be avoided.  That's independent of the language involved, in any 
language, circular dependencies are a code smell

Now, in Python in particular, first question is whether either x.py or 
y.py is your main script module (the one where you do the if __name__ == 
"__main__"  and the answer is yes).  If so, you're in big trouble, and 
you really need to rework it.  I could elaborate if needed, but trust 
me, you don't want to do this, even if it means writing one more module 
containing a single import line and just two or three more, and letting 
that be your script.

If that's not the case, next question is whether either module refers to 
the other one at import time, or only from inside def and class 
definitions.  If you have any top-level code going on, other than 
imports, and this code actually uses a symbol from the other module, 
you're probably in trouble.  Not as bad as first case, but still worth 
avoiding.  Sometimes this can be kludged past, by reordering things a 
little bit, maybe by moving one of the imports further down in the file.

Now back to the code smell.  If the modules really depend on each other, 
you should consider factoring out those dependencies and move them to a 
third module that both import.  Figure out why the modules are broken up 
in the particular way they are, and how you can eliminate circular 
references by refactoring.  It's hard for me to come up with general 
principles, but perhaps an example or three will help.

If a callee needs configuration information stored in globals of the 
caller, then you probably need to add that config information as parameters.

If an object needs a reference to functions in another module, add them 
when constructing the object, not statically.

Or maybe even have the one module explicitly set global variables in the 
other module, so they're in one place, instead of being only in the 
namespace of the code initializing them.

That's the best I can do without something concrete to adjust.

DaveA


From ryankaskel at gmail.com  Sat Jul 11 13:56:48 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Sat, 11 Jul 2009 10:56:48 -0700 (PDT)
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
	<h3a865$tij$03$1@news.t-online.com>
Message-ID: <b4557401-ed2f-41fa-b98c-3ab03ff47944@e18g2000vbe.googlegroups.com>

Okay so below is the acutal code. I am starting to think there is no
reason why I can't install the post_save signal in signals.py itself
and thereby avoid this issue entirely.

models.py:

class Link(CommonAbstractModel):
    ...

class Menu(CommonAbstractModel):
    ....

class StaticPage(CommonAbstractModel):
   ,,,

class CachedMenuXhtml(CommonAbstractModel):
   ...

post_save.connect(signals.build_menu, sender=Link)
post_save.connect(signals.build_menu, sender=Menu)

--------------------

# Signlas for caching of menu XHTML

class GenerateMenuXhtml(threading.Thread):

    def __init__(self, instance):
        from asqcom.apps.staticpages.models import Menu, Link,
CachedMenuXhtml
        self.Link = Link
        self.Menu = Menu
        self.CachedMenuXhtml = CachedMenuXhtml

# Function to run on post_save signal
def build_menu(sender, instance, **kwargs):
    GenerateMenuXhtml(instance).start()



From digitig at gmail.com  Sat Jul 11 14:33:19 2009
From: digitig at gmail.com (Tim Rowe)
Date: Sat, 11 Jul 2009 19:33:19 +0100
Subject: Clarity vs. code reuse/generality
In-Reply-To: <0267ffdf$0$18215$c3e8da3@news.astraweb.com>
References: <h2l36k$q5l$1@reader1.panix.com>
	<7xzlbkti7z.fsf@ruckus.brouhaha.com> <h2ogli$n9p$2@reader1.panix.com>
	<mailman.2700.1246895025.8015.python-list@python.org>
	<h33k3d$2uu$1@reader1.panix.com>
	<mailman.2872.1247126235.8015.python-list@python.org>
	<pan.2009.07.10.02.28.04.344000@nowhere.com>
	<pan.2009.07.10.02.57.44@REMOVE.THIS.cybersource.com.au>
	<mailman.2962.1247243254.8015.python-list@python.org>
	<0267ffdf$0$18215$c3e8da3@news.astraweb.com>
Message-ID: <aee48b3c0907111133q6194fba4qdffd7018f6794bb6@mail.gmail.com>

2009/7/11 Steven D'Aprano <steve at remove-this-cybersource.com.au>:

> So is design-by-contract just another way of saying "let's hope the data
> is valid, because if it's not, we're screwed"?

Not at all. Design By Contract is about assigning responsibility for
checking. If you don't assign responsibility then a pile of things end
up getting checked over and over again, because everybody is assuming
responsibility, and some things don't get checked at all because
everyone assumes that somebody else is checking.

In DbC, the pre-condition on data coming in to a program from outside
will usually simply be "true" -- nothing at all is assumed about it.
But when you pass it from an input conditioning routine to a
processing routine, the input conditioning routine should be able to
make guarantees about what it passes, and the processing routine
should be able to assume that those guarantees are met without having
to check it again (after all, what was the conditioning routine there
for?). Assertions might be useful in testing (because they save having
to repeat the same set of test cases on absolutely every test run) and
they're certainly useful in documenting, but if they're any use at all
in the production run-time then there's something wrong with your
development and testing processes.

-- 
Tim Rowe


From piet at cs.uu.nl  Sat Jul 11 17:21:53 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 11 Jul 2009 23:21:53 +0200
Subject: Threading.Condition problem
References: <mailman.2957.1247240742.8015.python-list@python.org>
Message-ID: <m21vom6hla.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Sorry if this appears twice, I sent it once with an attachment and it never
>GR> arrived so maybe the attachment is posing problems. I inlined the code this
>GR> time (at the bottom), thank you,

>GR> Gabriel

>GR> ########################## Original message ############################

>GR> Hello everyone,

>GR> I wrote a small example that listens for xmpp msgs in a thread. The main
>GR> program calls a function that blocks (using Condition.wait) until a msg
>GR> has been received and then returns the msg. When a msg arrives, it is
>GR> put in a variable in the thread's object, it then calls the notify()
>GR> attr on the Condition object. For some reason, this doesn't work, the
>GR> thread gets the msg, tries to notify the Condition object, fails because
>GR> the lock has not been acquired yet and blocks. I tried ignoring the
>GR> failure, thinking that since it has not been acquired yet then when it
>GR> is, it will get the msg right away and never call Condition.wait, thus
>GR> not causing any problems, but this does not work either. Does someone
>GR> know what I am doing wrong? I attached the code to this msg.

The code that puts the message in the variable should also acquire the
lock:


     def onMessage(self, conn, msg):
         with self._cv:
             self.message = msg
             self._cv.notify()

A couple of remarks:

1. I think the code is neater if all manipulation with the condition is
   done in the same class (actually in the same instance -- making this
   instance into a monitor).

class Listener(Thread):
    def __init__(self, ws):
        Thread.__init__(self)
        self.interrupt = Event()
        self.message = None
        self._cv = Condition()
        self.client = ws._client
        self.client.RegisterHandler('message', self.onMessage)
    
    def onMessage(self, conn, msg):
        with self._cv:
            self.message = msg
            try:
                self._cv.notify()
            except RuntimeError:
                print "self._cv has not acquired the lock yet"
    
    def getMsg(self):
        with self._cv:
            while !self.message
                self._cv.wait()
            return self.message

class WS(object):
    def __init__(self, username, password, res):
        self._jid = xmpp.protocol.JID(username)
        self._client = xmpp.Client(self._jid.getDomain())
#        self._cv = Condition()
    
    def getMsg(self, mid=None):
        """
        """
        return self._listener.getMsg()

Of course I haven't tested this code as I don't have the context
modules.

2. I don't know if more than one message can be delivered in the same
   instance. If yes, than your code will not work, and neither will the
   code above as, the message instance variable is never cleared. So the
   next getMsg will be happy to deliver the previous one.
   You would have to clear it when returning this one.
    
    def getMsg(self):
        with self._cv:
            while !self.message
                self._cv.wait()
            msg = self.message
            self.message = None
            return msg

3. If the messages come in faster than they can be processed some will
   be lost as they will overwrite the previous one in the self.message
   variable. The solution is to use a threading.Queue to transfer the
   messages from one thread to the other. This also saves you the hassle
   of doing your own synchronisation like above. If you are not familiar
   with synchronising multithreaded applications it is very easy to make
   errors and even if you are it is quite easy to do them wrong. I have
   been involved in distributed programming courses at university level
   and I have seen many errors in this area.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mail.to.daniel.platz at googlemail.com  Sat Jul 11 18:33:32 2009
From: mail.to.daniel.platz at googlemail.com (Daniel Platz)
Date: Sat, 11 Jul 2009 15:33:32 -0700 (PDT)
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
Message-ID: <e038b7f1-400f-43c7-85bc-df81170353c0@r34g2000vba.googlegroups.com>

Hi,

thanks for your repleys. I have tried matplotlib but it is extremely
slow. I think it is more optimized for good looking plots instead of
speed. I do not know the Python bindings of gnuplot and Veusz. To
clarify the issue again, by 25000 data points I mean 25000 pixels,
i.e. corresponding (x,y) pairs. Thus the mapping to one pixel on the
screen is not unique.

Now, that I have to implement this problem on my own I am very
impressed by the plotting capabilities of LabView which brings thounds
of data points on screen in an extremely short time.

Thanks for your help.

Best regards,

Daniel


From ben+python at benfinney.id.au  Sat Jul 11 19:27:23 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 12 Jul 2009 09:27:23 +1000
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
	<e038b7f1-400f-43c7-85bc-df81170353c0@r34g2000vba.googlegroups.com>
Message-ID: <87vdlyls10.fsf@benfinney.id.au>

Daniel Platz <mail.to.daniel.platz at googlemail.com> writes:

> I do not know the Python bindings of gnuplot and Veusz.

A web search does, though.

    <URL:http://clusty.com/search?query=gnuplot+python>
    <URL:http://clusty.com/search?query=veusz+python>

-- 
 \        ?The problem with television is that the people must sit and |
  `\    keep their eyes glued on a screen: the average American family |
_o__)                 hasn't time for it.? ?_The New York Times_, 1939 |
Ben Finney


From ryankaskel at gmail.com  Sat Jul 11 19:43:10 2009
From: ryankaskel at gmail.com (Ryan K)
Date: Sat, 11 Jul 2009 16:43:10 -0700 (PDT)
Subject: Addind imports to a class namespace
References: <b82795dd-b44d-4bc8-81d8-9a6581556983@37g2000yqp.googlegroups.com>
	<h39cpr$o4u$01$1@news.t-online.com>
	<89bd4a17-8476-41bc-8728-bf840a64390b@s6g2000vbp.googlegroups.com>
	<h3a865$tij$03$1@news.t-online.com>
	<b4557401-ed2f-41fa-b98c-3ab03ff47944@e18g2000vbe.googlegroups.com>
Message-ID: <3a6a9820-ab17-4ddc-a75b-a6b49b919af3@p15g2000vbl.googlegroups.com>

Thank you for your replies. I have factored out the dependency and
everything is solved.

Cheers,
Ryan


From ldo at geek-central.gen.new_zealand  Sat Jul 11 20:21:12 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 12 Jul 2009 12:21:12 +1200
Subject: 2.4 VS 3.1 for simple print
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
	<87hbxkm7n2.fsf@benfinney.id.au>
Message-ID: <h3ba9o$52m$3@lust.ihug.co.nz>

In message <87hbxkm7n2.fsf at benfinney.id.au>, Ben Finney wrote:

> For this and other differences introduced in the Python 3.x series, see
> <URL:http://www.python.org/dev/peps/pep-3100/>.

People never thank you for an "RTFM" response.



From ldo at geek-central.gen.new_zealand  Sat Jul 11 20:25:02 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Sun, 12 Jul 2009 12:25:02 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32eoh$ql8$1@reader1.panix.com>
	<h32fon$264$1@panix3.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com>
Message-ID: <h3bagu$52m$4@lust.ihug.co.nz>

In message <h37gv5$r81$1 at panix3.panix.com>, Aahz wrote:

> It helps to remember that names and namespaces are in many
> ways syntactic sugar for dicts or lists.

Interesting, though, that Python insists on maintaining a distinction 
between c["x"] and c.x, whereas JavaScript doesn't bother.



From greg at cosc.canterbury.ac.nz  Sat Jul 11 21:28:17 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sun, 12 Jul 2009 13:28:17 +1200
Subject: tough-to-explain Python
In-Reply-To: <mailman.3005.1247313872.8015.python-list@python.org>
References: <h309ot$bii$1@reader1.panix.com><5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com><h3234l$aod$1@reader1.panix.com><mailman.2839.1247060874.8015.python-list@python.org><b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com><00720d76$0$9710$c3e8da3@news.astraweb.com><mailman.2944.1247223458.8015.python-list@python.org>	<007318de$0$9710$c3e8da3@news.astraweb.com>
	<mailman.3005.1247313872.8015.python-list@python.org>
Message-ID: <7bssfuF24o01hU1@mid.individual.net>

Hendrik van Rooyen wrote:

> The creativity could, arguably, be in the "Design".
> Not in the translation to python, or assembler.
> No way.  That is just coding.

No, the mechanical part of the process is called compiling,
and we have programs to do it for us.

By the time you've specified the design so rigorously
that not the slightest spark of creativity is needed
to implement it, you *have* coded it.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Sat Jul 11 21:34:27 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sun, 12 Jul 2009 13:34:27 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
In-Reply-To: <h3bagu$52m$4@lust.ihug.co.nz>
References: <h3291j$mfu$1@reader1.panix.com> <h32eoh$ql8$1@reader1.panix.com>
	<h32fon$264$1@panix3.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
Message-ID: <7bssrgF251u00U1@mid.individual.net>

Lawrence D'Oliveiro wrote:

> Interesting, though, that Python insists on maintaining a distinction 
> between c["x"] and c.x, whereas JavaScript doesn't bother.

And that distinction is a good thing. It means, for
example, that dictionaries can have methods without
colliding with the key space of the items put into
them.

-- 
Greg


From clp2 at rebertia.com  Sat Jul 11 21:50:28 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 11 Jul 2009 18:50:28 -0700
Subject: explode()
In-Reply-To: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
Message-ID: <50697b2c0907111850sda1fd84k65f017f2553b639a@mail.gmail.com>

On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
> ? ? ? ?What is the Python equivalent of the PHP explode() function?

some_string.split("separator")

Cheers,
Chris
-- 
http://blog.rebertia.com


From fatkinson at mishmash.com  Sat Jul 11 22:41:12 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Sat, 11 Jul 2009 19:41:12 -0700
Subject: explode()
Message-ID: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>

	What is the Python equivalent of the PHP explode() function?  





							Fred 


From sjmachin at lexicon.net  Sat Jul 11 23:01:35 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 12 Jul 2009 03:01:35 +0000 (UTC)
Subject: A zlib question
References: <80F42625-5FB2-438F-AFF2-913236A6D336@catalogix.se>
Message-ID: <loom.20090712T021938-451@post.gmane.org>

Roland Hedberg <roland <at> catalogix.se> writes:

> I have a problem with zlib and compressing/decompressing according to  
> RFC 1951.
> 
> It seems like I can decompress, something compressed according to RFC  
> 1951 by someone else, provided I set wbits to something negative (used  
> -8 but I guess any negative number would work?).

-15 will get you a 32KB window which is the best
and is the default in APIs
where a default is possible.

original_data = zlib.decompress(deflated_data, -15)

 
> But how can I compress using zlib so it doesn't add a gzip header ?

You don't need to, because zlib doesn't add a gzip header
(RFC 1952) -- it adds a zlib header (RFC 1950)
... without out any frills (i.e. default case) a zlib
stream is a 2-byte header plus the RFC 1951 deflate stream
plus a 4-byte checksum.

deflated_data = zlib.compress(uncompressed_data)[2:-4]

Coincidentally this question arose elsewhere very recently: see

http://stackoverflow.com/questions/1089662/
python-inflate-and-deflate-implementations

concatenate the above two lines -- gmane <= 80-byte line limit 8-P

BTW FWIW, one can evidently force zlib to do a gzip wrapper
instead of a zlib wrapper by setting wbits to positive > 15
[brilliant API design], but one might 
be better off using the gzip module directly ...

HTH,
John




From fatkinson at mishmash.com  Sat Jul 11 23:20:41 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Sat, 11 Jul 2009 20:20:41 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
Message-ID: <vjli55dl08g2o2otffiq25ehgl6t8v2qos@4ax.com>

On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
wrote:

>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>
>some_string.split("separator")
>
>Cheers,
>Chris

Thanks, 



						Fred 


From aahz at pythoncraft.com  Sun Jul 12 00:23:43 2009
From: aahz at pythoncraft.com (Aahz)
Date: 11 Jul 2009 21:23:43 -0700
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
Message-ID: <h3bogf$oo0$1@panix3.panix.com>

In article <h3bagu$52m$4 at lust.ihug.co.nz>,
Lawrence D'Oliveiro  <ldo at geek-central.gen.new_zealand> wrote:
>In message <h37gv5$r81$1 at panix3.panix.com>, Aahz wrote:
>>
>> It helps to remember that names and namespaces are in many
>> ways syntactic sugar for dicts or lists.
>
>Interesting, though, that Python insists on maintaining a distinction 
>between c["x"] and c.x, whereas JavaScript doesn't bother.

Why do you say "insists"?

class AttrDict:
    def __getitem__(self, key):
        return getattr(self, key)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"as long as we like the same operating system, things are cool." --piranha


From blepctc at free.fr  Sun Jul 12 03:47:32 2009
From: blepctc at free.fr (Baptiste Lepilleur)
Date: Sun, 12 Jul 2009 09:47:32 +0200
Subject: Looking for a tool to checkfor  python script backward compatibility
Message-ID: <4a59951a$0$10853$426a74cc@news.free.fr>

I'm looking for a tool that could be used in a pre-commit step to check that 
only features available in a "old" python version are used, say python 2.3 
for example.

Does any one know of one ? 




From vs at it.uu.se  Sun Jul 12 05:21:51 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Sun, 12 Jul 2009 11:21:51 +0200
Subject: PyODE
Message-ID: <4A59AB2F.4060708@it.uu.se>

Does anyone have PyODE running on Python 2.6.2?

--V



From ben+python at benfinney.id.au  Sun Jul 12 05:34:56 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 12 Jul 2009 19:34:56 +1000
Subject: 2.4 VS 3.1 for simple print
References: <qfedne7Zv6A1MsrXnZ2dnUVZ_vadnZ2d@earthlink.com>
	<87hbxkm7n2.fsf@benfinney.id.au> <h3ba9o$52m$3@lust.ihug.co.nz>
Message-ID: <87r5wmkzwf.fsf@benfinney.id.au>

Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> writes:

> In message <87hbxkm7n2.fsf at benfinney.id.au>, Ben Finney wrote:
> 
> > For this and other differences introduced in the Python 3.x series, see
> > <URL:http://www.python.org/dev/peps/pep-3100/>.
> 
> People never thank you for an "RTFM" response.

It's a good thing I avoid giving such responses, then. (Pointing someone
to the specific document isn't ?RTFM?.)

-- 
 \                 ?Leave nothing to chance. Overlook nothing. Combine |
  `\          contradictory observations. Allow yourself enough time.? |
_o__)                                                     ?Hippocrates |
Ben Finney


From skip at pobox.com  Sun Jul 12 09:01:23 2009
From: skip at pobox.com (skip at pobox.com)
Date: Sun, 12 Jul 2009 08:01:23 -0500
Subject: Implementing a cache
In-Reply-To: <87ab3cwu3u.fsf@vostro.rath.org>
References: <87ab3cwu3u.fsf@vostro.rath.org>
Message-ID: <19033.56995.644542.486528@montanaro.dyndns.org>


    Nikolaus> I want to implement a caching data structure in Python that
    Nikolaus> allows me to:

    Nikolaus>  1. Quickly look up objects using a key
    Nikolaus>  2. Keep track of the order in which the objects are accessed
    Nikolaus>     (most recently and least recently accessed one, not a
    Nikolaus>     complete history)
    Nikolaus>  3. Quickly retrieve and remove the least recently accessed
    Nikolaus>     object.

My Cache module does #1 and #3.  I'm not sure if you want #2 for internal
cache maintenance or for as part of the API.

    http://www.smontanaro.net/python/Cache.py

Skip


From pdpinheiro at gmail.com  Sun Jul 12 09:27:23 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Sun, 12 Jul 2009 06:27:23 -0700 (PDT)
Subject: Implementing a cache
References: <87ab3cwu3u.fsf@vostro.rath.org>
	<mailman.3026.1247403701.8015.python-list@python.org>
Message-ID: <a9ad1d79-8308-4821-8fe8-c053b094c229@j9g2000vbp.googlegroups.com>

On Jul 12, 2:01?pm, s... at pobox.com wrote:
> ? ? Nikolaus> I want to implement a caching data structure in Python that
> ? ? Nikolaus> allows me to:
>
> ? ? Nikolaus> ?1. Quickly look up objects using a key
> ? ? Nikolaus> ?2. Keep track of the order in which the objects are accessed
> ? ? Nikolaus> ? ? (most recently and least recently accessed one, not a
> ? ? Nikolaus> ? ? complete history)
> ? ? Nikolaus> ?3. Quickly retrieve and remove the least recently accessed
> ? ? Nikolaus> ? ? object.
>
> My Cache module does #1 and #3. ?I'm not sure if you want #2 for internal
> cache maintenance or for as part of the API.
>
> ? ?http://www.smontanaro.net/python/Cache.py
>
> Skip

I'm not sure whether #2 is doable at all, as written. You _need_ a
complete history (at least the full ordering of the items in the
cache) to be able to tell what the least recently used item is.


From exarkun at divmod.com  Sun Jul 12 09:39:43 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Sun, 12 Jul 2009 09:39:43 -0400
Subject: Looking for a tool to checkfor python script backward
	compatibility
In-Reply-To: <4a59951a$0$10853$426a74cc@news.free.fr>
Message-ID: <20090712133943.2543.62461196.divmod.quotient.1539@henry.divmod.com>

On Sun, 12 Jul 2009 09:47:32 +0200, Baptiste Lepilleur <blepctc at free.fr> wrote:
>I'm looking for a tool that could be used in a pre-commit step to check that
>only features available in a "old" python version are used, say python 2.3
>for example.
>
>Does any one know of one ?
>

Run your test suite with whichever versions of Python you want to support.

Tools like Hudson (<https://hudson.dev.java.net/>) and BuildBot
(<http://buildbot.net/>) can help with this.

Jean-Paul


From stef.mientki at gmail.com  Sun Jul 12 09:40:27 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 12 Jul 2009 15:40:27 +0200
Subject: how to run the "main" section of another module ?
Message-ID: <4A59E7CB.5020908@gmail.com>

hello,

when I''m working in a library,
and want to test some of the library functions,
I need to switch to  a main application,
(which has a normal main-section)
and run that.

If the library is simply,
I add a main section to the library,
so no problem.

But if the library requires a lot of overhead,
I want to run some main program,
that has a main section,
and uses my library under construction.

So how do I call from within the library module,
in a main section in that library module,
a main in another module ?

thanks,
Stef Mientki


From skip at pobox.com  Sun Jul 12 09:40:45 2009
From: skip at pobox.com (skip at pobox.com)
Date: Sun, 12 Jul 2009 08:40:45 -0500
Subject: Implementing a cache
In-Reply-To: <a9ad1d79-8308-4821-8fe8-c053b094c229@j9g2000vbp.googlegroups.com>
References: <87ab3cwu3u.fsf@vostro.rath.org>
	<mailman.3026.1247403701.8015.python-list@python.org>
	<a9ad1d79-8308-4821-8fe8-c053b094c229@j9g2000vbp.googlegroups.com>
Message-ID: <19033.59357.223527.248051@montanaro.dyndns.org>


    >> My Cache module does #1 and #3. ?I'm not sure if you want #2 for
    >> internal cache maintenance or for as part of the API.
    >> 
    >> ? ?http://www.smontanaro.net/python/Cache.py

    pdpi> I'm not sure whether #2 is doable at all, as written. You _need_ a
    pdpi> complete history (at least the full ordering of the items in the
    pdpi> cache) to be able to tell what the least recently used item is.

I should have added that my Cache module does maintain a history.  (Clearly
it needs that to determine the LRU item.)  It is exposed as part of the API
via the ftimes method.

S


From stef.mientki at gmail.com  Sun Jul 12 09:47:27 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 12 Jul 2009 15:47:27 +0200
Subject: how to run the "main" section of another module ?
In-Reply-To: <4A59E7CB.5020908@gmail.com>
References: <4A59E7CB.5020908@gmail.com>
Message-ID: <4A59E96F.6080709@gmail.com>

Stef Mientki wrote:
> hello,
>
> when I''m working in a library,
> and want to test some of the library functions,
> I need to switch to  a main application,
> (which has a normal main-section)
> and run that.
>
> If the library is simply,
> I add a main section to the library,
> so no problem.
>
> But if the library requires a lot of overhead,
> I want to run some main program,
> that has a main section,
> and uses my library under construction.
>
> So how do I call from within the library module,
> in a main section in that library module,
> a main in another module ?
>
> thanks,
> Stef Mientki

btw,
I just found this in one of my programs (which works but isn't very 
beautiful)

In the library fill under construction I put this main section:
(sb_test.py is the main program, that has a main section and uses the 
library under construction)

if __name__ == '__main__':
    import db_test
    new_globals = {}
    new_globals [ '__name__' ] = '__main__'
    new_globals [ '__file__' ] = 'not really valuable'
    execfile ( 'db_test.py', new_globals )
 



From aahz at pythoncraft.com  Sun Jul 12 10:21:55 2009
From: aahz at pythoncraft.com (Aahz)
Date: 12 Jul 2009 07:21:55 -0700
Subject: how to run the "main" section of another module ?
References: <mailman.3028.1247406021.8015.python-list@python.org>
Message-ID: <h3cri3$171$1@panix3.panix.com>

In article <mailman.3028.1247406021.8015.python-list at python.org>,
Stef Mientki  <stef.mientki at gmail.com> wrote:
>
>when I''m working in a library, and want to test some of the library
>functions, I need to switch to a main application, (which has a normal
>main-section) and run that.

if __name__ == '__main__':
    main()

Then you can call main() from another module for testing purposes.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From piet at cs.uu.nl  Sun Jul 12 11:54:30 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 12 Jul 2009 17:54:30 +0200
Subject: how to run the "main" section of another module ?
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
Message-ID: <m2fxd1522x.fsf@cs.uu.nl>

>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:

>SM> Stef Mientki wrote:
>>> hello,
>>> 
>>> when I''m working in a library,
>>> and want to test some of the library functions,
>>> I need to switch to  a main application,
>>> (which has a normal main-section)
>>> and run that.
>>> 
>>> If the library is simply,
>>> I add a main section to the library,
>>> so no problem.
>>> 
>>> But if the library requires a lot of overhead,
>>> I want to run some main program,
>>> that has a main section,
>>> and uses my library under construction.
>>> 
>>> So how do I call from within the library module,
>>> in a main section in that library module,
>>> a main in another module ?
>>> 
>>> thanks,
>>> Stef Mientki

>SM> btw,
>SM> I just found this in one of my programs (which works but isn't very
>SM> beautiful)

>SM> In the library fill under construction I put this main section:
>SM> (sb_test.py is the main program, that has a main section and uses the
>SM> library under construction)

>SM> if __name__ == '__main__':
>SM>    import db_test
>SM>    new_globals = {}
>SM>    new_globals [ '__name__' ] = '__main__'
>SM>    new_globals [ '__file__' ] = 'not really valuable'
>SM>    execfile ( 'db_test.py', new_globals )

Why not:

import db_test
db_test.main()

I think that is what Aahz meant.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From bjorn.m.meyer at gmail.com  Sun Jul 12 13:16:13 2009
From: bjorn.m.meyer at gmail.com (Bjorn Meyer)
Date: Sun, 12 Jul 2009 11:16:13 -0600
Subject: multiprocessing and dictionaries
Message-ID: <200907121116.13828.bjorn.m.meyer@gmail.com>

I am trying to convert a piece of code that I am using the thread module with 
to the multiprocessing module.

The way that I have it set up is a chunk of code reads a text file and assigns 
a dictionary key multiple values from the text file. I am using locks to write 
the values to the dictionary.
The way that the values are written is as follows:
	mydict.setdefault(key, []).append(value)

The problem that I have run into is that using multiprocessing, the key gets 
set, but the values don't get appended.
I've even tried the Manager().dict() option, but it doesn't seem to work.

Is this not supported at this time or am I missing something?

Thanks in advance.

Bjorn


From stef.mientki at gmail.com  Sun Jul 12 14:13:53 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 12 Jul 2009 20:13:53 +0200
Subject: how to run the "main" section of another module ?
In-Reply-To: <m2fxd1522x.fsf@cs.uu.nl>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl>
Message-ID: <4A5A27E1.1090502@gmail.com>


>> SM> if __name__ == '__main__':
>> SM>    import db_test
>> SM>    new_globals = {}
>> SM>    new_globals [ '__name__' ] = '__main__'
>> SM>    new_globals [ '__file__' ] = 'not really valuable'
>> SM>    execfile ( 'db_test.py', new_globals )
>>     
>
> Why not:
>
> import db_test
> db_test.main()
>
> I think that is what Aahz meant.
>
>   
Yes I tried that too,
but it gives the following error:
"module object not callable"


db_text.__main__()
gives error:
'module' object has no attribute '__main__'

cheers,
Stef



From aahz at pythoncraft.com  Sun Jul 12 14:44:10 2009
From: aahz at pythoncraft.com (Aahz)
Date: 12 Jul 2009 11:44:10 -0700
Subject: how to run the "main" section of another module ?
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl>
	<mailman.3032.1247422431.8015.python-list@python.org>
Message-ID: <h3datq$k83$1@panix3.panix.com>

In article <mailman.3032.1247422431.8015.python-list at python.org>,
Stef Mientki  <stef.mientki at gmail.com> wrote:
>Stef deleted an attribution:
>>
>> Why not:
>>
>> import db_test
>> db_test.main()
>   
>Yes I tried that too, but it gives the following error: "module object
>not callable"

You need to create a main() function in db_test first.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From emile at fenx.com  Sun Jul 12 14:48:25 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 12 Jul 2009 11:48:25 -0700
Subject: how to run the "main" section of another module ?
In-Reply-To: <4A5A27E1.1090502@gmail.com>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>
	<4A5A27E1.1090502@gmail.com>
Message-ID: <h3db5t$9r9$1@ger.gmane.org>

On 7/12/2009 11:13 AM Stef Mientki said...
> 
>>> SM> if __name__ == '__main__':
>>> SM>    import db_test
>>> SM>    new_globals = {}
>>> SM>    new_globals [ '__name__' ] = '__main__'
>>> SM>    new_globals [ '__file__' ] = 'not really valuable'
>>> SM>    execfile ( 'db_test.py', new_globals )
>>>     
>>
>> Why not:

implied here is that you restructure...

>>
>> import db_test
>> db_test.main()
>>
>> I think that is what Aahz meant.
>>
>>   
> Yes I tried that too,
> but it gives the following error:
> "module object not callable"
> 
> 
> db_text.__main__()
> gives error:
> 'module' object has no attribute '__main__'
> 

You see, we're further assuming you've structured the module for this 
purpose.  IOW, your module should end with:

if __name__ == '__main__':
     main()

and nothing more.  Then, you can do:

import db_test
db_test.main()

Emile



From cameron.pulsford at gmail.com  Sun Jul 12 15:11:55 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Sun, 12 Jul 2009 15:11:55 -0400
Subject: Question about generators
In-Reply-To: <h3db5t$9r9$1@ger.gmane.org>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>
	<4A5A27E1.1090502@gmail.com> <h3db5t$9r9$1@ger.gmane.org>
Message-ID: <7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>

Hey everyone, I have this small piece of code that simply finds the  
factors of a number.

import sys

def factor(n):
     primes = (6*i+j for i in xrange(1, n) for j in [1, 5] if (i+j)%5 ! 
= 0)

     factors = []

     for i in [2, 3, 5]:
         while n % i == 0:
             n /= i
             factors.append(i)
     for i in primes:
         while n % i == 0:
             n /= i
             factors.append(i)
     print factors

factor(int(sys.argv[1]))

My question is, is it possible to combine those two loops? The primes  
generator I wrote finds all primes up to n, except for 2, 3 and 5, so  
I must check those explicitly. Is there anyway to concatenate the hard  
coded list of [2,3,5] and the generator I wrote so that I don't need  
two for loops that do the same thing?

I tried writing a primes function using yield statements, but it  
didn't work like I thought it would.


From alan.kesselmann at gmail.com  Sun Jul 12 15:16:29 2009
From: alan.kesselmann at gmail.com (zayatzz)
Date: Sun, 12 Jul 2009 12:16:29 -0700 (PDT)
Subject: Sockets and threading
Message-ID: <0b77e7b9-85cd-4a23-b975-5cb8ac59fe7e@j19g2000vbp.googlegroups.com>

Im trying to get aquinted to python on bit more basic level and am
following socket and threading programming tutorials from these 2
addresses :

http://heather.cs.ucdavis.edu/~matloff/Python/PyNet.pdf
http://heather.cs.ucdavis.edu/~matloff/Python/PyThreads.pdf

in this PyThreads file he sets up threaded server app which listens to
what clients send to it and echos it back to clients while adding sent
info into one string.

The problem is that the code does not work for me.

class srvr(threading.Thread):
	v = ""
	vlock = threading.Lock()
	id = 0
	def __init__(self,clntsock):
		threading.Thread.__init__(self)
		self.myid = srvr.id
		srvr.id += 1
		self.myclntsock = clntsock
	def run(self):
		while 1:
			k = self.myclntsock.recv(1)
			if k == "": break
			srvr.vlock.acquire()
			srvr.v += k
			srvr.vlock.release()
			self.myclntsock.send(srvr.v)
			self.myclntsock.close()

Instead of sendint back i get this error :
  File "server3.py", line 31, in serveclient
    k = self.myclntsock.recv(1)
  File "/usr/lib/python2.6/socket.py", line 165, in _dummy
    raise error(EBADF, 'Bad file descriptor')
socket.error: [Errno 9] Bad file descriptor

As much as i understand this line 31 is supposed to recieve stuff from
clients and has buffer size 1. I dont understand what this has to do
with file descriptor.. whatever that is anyway.

Alan


From vodkalove at gmail.com  Sun Jul 12 15:18:04 2009
From: vodkalove at gmail.com (Riley Crane)
Date: Sun, 12 Jul 2009 12:18:04 -0700 (PDT)
Subject: MySQLdb + SSH Tunnel
Message-ID: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>

OVERVIEW:
I am running a script on one machine that connects to a MySQL database
on another machine that is outside of our university's domain.
According to the administrator, network policies do not allow the
compute nodes to access machines outside of our university's domain.

COMPUTERS:
A = compute node within university (I do not have shell access)
B = 2nd machine within university that does not block outside
connections (I have root access)
C = machine outside of university (I have root access)
mysqldb on A cannot connect to C ....but.....
mysqldb on A can connect to B

WHAT I WOULD LIKE TO DO:
Is it possible to set something up where A talks to a port on B, and
that port is actually nothing more than 3306 on C?  Can I do this with
an SSH tunnel?

Can anyone please give precise instructions?


From emile at fenx.com  Sun Jul 12 15:41:31 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 12 Jul 2009 12:41:31 -0700
Subject: MySQLdb + SSH Tunnel
In-Reply-To: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
Message-ID: <h3de9f$hgf$1@ger.gmane.org>

On 7/12/2009 12:18 PM Riley Crane said...
> OVERVIEW:
> I am running a script on one machine that connects to a MySQL database
> on another machine that is outside of our university's domain.
> According to the administrator, network policies do not allow the
> compute nodes to access machines outside of our university's domain.
> 
> COMPUTERS:
> A = compute node within university (I do not have shell access)
> B = 2nd machine within university that does not block outside
> connections (I have root access)

...so B can talk to C presumably...

> C = machine outside of university (I have root access)
> mysqldb on A cannot connect to C ....but.....
> mysqldb on A can connect to B



> 
> WHAT I WOULD LIKE TO DO:
> Is it possible to set something up where A talks to a port on B, and
> that port is actually nothing more than 3306 on C?  Can I do this with
> an SSH tunnel?
> 
> Can anyone please give precise instructions?

ssh with something like...

ssh -lroot -L3306:C:3306 B

Watch out for other instances of mysql on A or B...

Emile




From mensanator at aol.com  Sun Jul 12 15:47:46 2009
From: mensanator at aol.com (Mensanator)
Date: Sun, 12 Jul 2009 12:47:46 -0700 (PDT)
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org> 
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org> 
	<mailman.3034.1247426204.8015.python-list@python.org>
Message-ID: <173f9127-2846-46a4-8392-6a7f03fde6e1@j19g2000vbp.googlegroups.com>

On Jul 12, 2:11?pm, Cameron Pulsford <cameron.pulsf... at gmail.com>
wrote:
> Hey everyone, I have this small piece of code that simply finds the ?
> factors of a number.
>
> import sys
>
> def factor(n):
> ? ? ?primes = (6*i+j for i in xrange(1, n) for j in [1, 5] if (i+j)%5 !
> = 0)
>
> ? ? ?factors = []
>
> ? ? ?for i in [2, 3, 5]:
> ? ? ? ? ?while n % i == 0:
> ? ? ? ? ? ? ?n /= i
> ? ? ? ? ? ? ?factors.append(i)
> ? ? ?for i in primes:
> ? ? ? ? ?while n % i == 0:
> ? ? ? ? ? ? ?n /= i
> ? ? ? ? ? ? ?factors.append(i)
> ? ? ?print factors
>
> factor(int(sys.argv[1]))
>
> My question is, is it possible to combine those two loops?

Yeah, get rid of the first loop.

> The primes ?
> generator I wrote finds all primes up to n, except for 2, 3 and 5, so ?
> I must check those explicitly. Is there anyway to concatenate the hard ?
> coded list of [2,3,5] and the generator I wrote so that I don't need ?
> two for loops that do the same thing?

primes.extend([2,3,5])

>
> I tried writing a primes function using yield statements, but it ?
> didn't work like I thought it would.



From vilya.harvey at gmail.com  Sun Jul 12 15:55:49 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Sun, 12 Jul 2009 20:55:49 +0100
Subject: Question about generators
In-Reply-To: <7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
Message-ID: <6aef848f0907121255n7d5cff37r6b01828cfb0ba6db@mail.gmail.com>

2009/7/12 Cameron Pulsford <cameron.pulsford at gmail.com>:
> My question is, is it possible to combine those two loops? The primes
> generator I wrote finds all primes up to n, except for 2, 3 and 5, so I must
> check those explicitly. Is there anyway to concatenate the hard coded list
> of [2,3,5] and the generator I wrote so that I don't need two for loops that
> do the same thing?

itertools.chain([2, 3, 5], primes) is what you're looking for, I think.

Vil.


From rhodri at wildebst.demon.co.uk  Sun Jul 12 16:13:58 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 12 Jul 2009 21:13:58 +0100
Subject: need to write a assembly progrm
In-Reply-To: <h393ob$d8u$2@ger.gmane.org>
References: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
	<op.uwup5bama8ncjz@gnudebst> <h393ob$d8u$2@ger.gmane.org>
Message-ID: <op.uwy05kura8ncjz@gnudebst>

On Sat, 11 Jul 2009 05:17:18 +0100, Dennis Lee Bieber  
<wlfraed at ix.netcom.com> wrote:

> On Fri, 10 Jul 2009 13:25:49 +0100, "Rhodri James"
> <rhodri at wildebst.demon.co.uk> declaimed the following in
> gmane.comp.python.general:
>
>> On Thu, 09 Jul 2009 11:52:44 +0100, m.reddy prasad reddy
>> <reddy.mrp at gmail.com> wrote:
>>
>> > my aim is to run the assembly programs in python.by that we can use  
>> that
>> > in
>> > the any labs.because we can run the python in the mobiles also.if we
>> > write
>> > assembly programs in the mobile ,the mobile act as a tool kit for the
>> > lab.tell me any other solutions for this
>>
>> Please define what you mean by "assembly".
>>
> 	The poorly punctuated paragraph sounds, to me, as if they mean they
> want (Windows assumed) EXE files that can be dropped onto remote/laptop
> machines without performing a full installation of Python...
>
> 	But yes... "assembly programs" does, to me, also mean things
> containing mnemonics for machine level opcodes.

Given that to me, "assembly programs" does not mean .EXE files at all,
not even a little bit, I'm prefering to refuse to guess :-)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Sun Jul 12 17:02:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 12 Jul 2009 23:02:46 +0200
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<mailman.3034.1247426204.8015.python-list@python.org>
Message-ID: <m28wit4nt5.fsf@cs.uu.nl>

>>>>> Cameron Pulsford <cameron.pulsford at gmail.com> (CP) wrote:

>CP> Hey everyone, I have this small piece of code that simply finds the
>CP> factors of a number.

Others have already given you advice to add the [2, 3, 5] to the
iterator (of which the primes.extend([2,3,5]) will not work). Please
allow me to make some other remarks.

>CP> import sys

>CP> def factor(n):
>CP>     primes = (6*i+j for i in xrange(1, n) for j in [1, 5] if (i+j)%5 ! = 0)

It is a bit misleading to call this `primes' as it will also contain
non-primes. Of course they don't harm as they will never be considered a
factor because all their prime factors will have been successfully
removed before this non prime will be considered.

>CP>     factors = []

>CP>     for i in [2, 3, 5]:
>CP>         while n % i == 0:
>CP>             n /= i
>CP>             factors.append(i)
>CP>     for i in primes:
>CP>         while n % i == 0:
>CP>             n /= i
>CP>             factors.append(i)

         You can stop the loop when n == 1. Like:
                 if n == 1: break

>CP>     print factors

>CP> factor(int(sys.argv[1]))

>CP> My question is, is it possible to combine those two loops? The primes
>CP> generator I wrote finds all primes up to n, except for 2, 3 and 5, so  I
>CP> must check those explicitly. Is there anyway to concatenate the hard  coded
>CP> list of [2,3,5] and the generator I wrote so that I don't need  two for
>CP> loops that do the same thing?

>CP> I tried writing a primes function using yield statements, but it  didn't
>CP> work like I thought it would.

See the recent thread `Why is my code faster with append() in a loop than with a large list?'
http://mail.python.org/pipermail/python-list/2009-July/718931.html
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From gagsl-py2 at yahoo.com.ar  Sun Jul 12 17:34:41 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 12 Jul 2009 18:34:41 -0300
Subject: Sockets and threading
References: <0b77e7b9-85cd-4a23-b975-5cb8ac59fe7e@j19g2000vbp.googlegroups.com>
Message-ID: <op.uwy4g9oqx6zn5v@gabriel.sleipnir-bsas>

En Sun, 12 Jul 2009 16:16:29 -0300, zayatzz <alan.kesselmann at gmail.com>
escribi?:

> 		while 1:
> 			k = self.myclntsock.recv(1)
> 			if k == "": break
> 			srvr.vlock.acquire()
> 			srvr.v += k
> 			srvr.vlock.release()
> 			self.myclntsock.send(srvr.v)
> 			self.myclntsock.close()
>
> Instead of sendint back i get this error :
>   File "server3.py", line 31, in serveclient
>     k = self.myclntsock.recv(1)
>   File "/usr/lib/python2.6/socket.py", line 165, in _dummy
>     raise error(EBADF, 'Bad file descriptor')
> socket.error: [Errno 9] Bad file descriptor
>
> As much as i understand this line 31 is supposed to recieve stuff from
> clients and has buffer size 1. I dont understand what this has to do
> with file descriptor.. whatever that is anyway.

That means the clntsock variable isn't an open, available socket. Note
that you close the socket right after sending the response - are you sure
you don't have an indentation error there?

-- 
Gabriel Genellina



From Samnsparky at gmail.com  Sun Jul 12 17:50:01 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 14:50:01 -0700 (PDT)
Subject: Webcam + GStreamer
Message-ID: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>

Hello! I need to stream from a webcam in Linux and I need to be able
to analyze the video feed frame by frame with PIL. Currently my web-
cam (Quickcam Chat) only seems to work with GStreamer so a solution
using pygst would be preferred.

Thanks for your help,
Sam


From piet at cs.uu.nl  Sun Jul 12 17:52:50 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 12 Jul 2009 23:52:50 +0200
Subject: Sockets and threading
References: <0b77e7b9-85cd-4a23-b975-5cb8ac59fe7e@j19g2000vbp.googlegroups.com>
Message-ID: <m24oth4lhp.fsf@cs.uu.nl>

>>>>> zayatzz <alan.kesselmann at gmail.com> (z) wrote:

>z> Im trying to get aquinted to python on bit more basic level and am
>z> following socket and threading programming tutorials from these 2
>z> addresses :

>z> http://heather.cs.ucdavis.edu/~matloff/Python/PyNet.pdf
>z> http://heather.cs.ucdavis.edu/~matloff/Python/PyThreads.pdf

>z> in this PyThreads file he sets up threaded server app which listens to
>z> what clients send to it and echos it back to clients while adding sent
>z> info into one string.

>z> The problem is that the code does not work for me.

>z> class srvr(threading.Thread):
>z> 	v = ""
>z> 	vlock = threading.Lock()
>z> 	id = 0
>z> 	def __init__(self,clntsock):
>z> 		threading.Thread.__init__(self)
>z> 		self.myid = srvr.id
>z> 		srvr.id += 1
>z> 		self.myclntsock = clntsock
>z> 	def run(self):
>z> 		while 1:
>z> 			k = self.myclntsock.recv(1)
>z> 			if k == "": break
>z> 			srvr.vlock.acquire()
>z> 			srvr.v += k
>z> 			srvr.vlock.release()
>z> 			self.myclntsock.send(srvr.v)
>z> 			self.myclntsock.close()


The last line is wrongly indented. It should be outside the loop. Shift
it left so that it lines up with the while. 

What happens now is that the socket is closed after the first recv().
Then the next round in the loop fails because the myclntsock is closed.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From Samnsparky at gmail.com  Sun Jul 12 17:54:13 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 14:54:13 -0700 (PDT)
Subject: Webcam + GStreamer
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
Message-ID: <1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>

On Jul 12, 3:50?pm, Sparky <Samnspa... at gmail.com> wrote:
> Hello! I need to stream from a webcam in Linux and I need to be able
> to analyze the video feed frame by frame with PIL. Currently my web-
> cam (Quickcam Chat) only seems to work with GStreamer so a solution
> using pygst would be preferred.
>
> Thanks for your help,
> Sam

Sorry, to clarify I am just having a hard time capturing frames in a
way that I can access with PIL.


From davoodvahdati2009 at gmail.com  Sun Jul 12 18:24:57 2009
From: davoodvahdati2009 at gmail.com (Davood Vahdati)
Date: Sun, 12 Jul 2009 15:24:57 -0700 (PDT)
Subject: c++ Source Code for acm 2004-2005 problems
Message-ID: <03d25e16-97d2-4b09-8113-5011c0e0ded9@p28g2000vbn.googlegroups.com>

Dear Sirs And Madams :

it is an Acm programming competition Questions in year 2004-2005 .
could you please solve problems is question ? I  Wan't C++ Source Code
program About this questions OR Problems . thank you for your prompt
attention to this matter

your faithfully.
-----------------------------------------
29th ACM International Collegiate
Sponsored by
Programming Contest, 2004-2005
Sharif Preliminary Contest
Sharif University of Technology, 28 Oct. 2004

Problem B
(Program filename: B.CPP, B.DPR, B.PAS or B.java)

Parallelogram Counting
There are n distinct points in the plane, given by their integer
coordinates. Find the number of parallelograms whose
vertices lie on these points. In other words, find the number of 4-
element subsets of these points that can be written as
{A, B, C, D} such that AB || CD, and BC || AD. No four points are in a
straight line.
Input (filename: B.IN)
The first line of the input file contains a single integer t (1 ? t ?
10), the number of test cases. It is followed by the input

data for each test case.
The first line of each test case contains an integer n (1 ? n ? 1000).
Each of the next n lines, contains 2 space-separated
integers x and y (the coordinates of a point) with magnitude (absolute
value) of no more than 1000000000.

Output (Standard Output)
Output should contain t lines.
Line i contains an integer showing the number of the parallelograms as
described above for test case i.

Sample Input
2
6
0 0
2 0
4 0
1 1
3 1
5 1
7
-2 -1
8 9
5 7
1 1
4 8
2 0
9 8

Sample Output
5
6
----------------------------------------------------------------------------------------------------------------------
Problem B-Page 1 of 1

28th ACM International Collegiate
Sponsored by
Programming Contest, 2003-2004
Sharif Preliminary Contest
Sharif University of Technology, 14 Nov. 2003

Problem C
(Program filename: C.CPP or C.PAS or C.DPR or C.java)

Toy Storage
Mom and dad have a problem: their child, Reza, never puts his toys
away when he is finished playing with them.
They gave Reza a rectangular box to put his toys in. Unfortunately,
Reza is rebellious and obeys his parents by simply
throwing his toys into the box. All the toys get mixed up, and it is
impossible for Reza to find his favorite toys anymore.
Reza's parents came up with the following idea. They put cardboard
partitions into the box. Even if Reza keeps
throwing his toys into the box, at least toys that get thrown into
different partitions stay separate. The box looks like this
from the top:

We want for each positive integer t, such that there exists a
partition with t toys, determine how many partitions
have t, toys.
Input (filename: C.IN)
The input consists of a number of cases. The first line consists of
six integers n, m, x1, y1, x2, y2. The number of
cardboards to form the partitions is n (0< n ? 1000) and the number of
toys is given in m (0<m ? 1000). The
coordinates of the upper-left corner and the lower-right corner of the
box are (x1, y1) and (x2, y2), respectively. The
following n lines each consists of two integers Ui Li, indicating that
the ends of the ith cardboard is at the coordinates
(Ui, y1) and (Li, y2). You may assume that the cardboards do not
intersect with each other. The next m lines each consists
of two integers Xi Yi specifying where the ith toy has landed in the
box. You may assume that no toy will land on a
cardboard.
A line consisting of a single 0 terminates the input.
Output (filename: C.OUT)
For each box, first provide a header stating ?Box?
on a line of its own. After that, there will be one line of output
per
count (t> 0) of toys in a partition. The value t will be followed by a
colon and a space, followed the number of
partitions containing t toys. Output will be sorted in ascending order
of t for each box.
Sample Input
4 10 0 10 100 0
20 20
80 80
60 60
40 40
5 10
15 10
95 10
25 10
65 10
75 10
35 10
45 10
55 10
85 10
5 6 0 10 60 0

4 3
15 30
3 1
6 8
10 10
2 1
2 8
1 5
5 5
40 10
7 9
0

Sample Output
Box

2: 5
Box
1: 4
2: 1
----------------------------------------------------------------------
29th ACM International Collegiate
Sponsored by
Programming Contest, 2004-2005
Sharif Preliminary Contest
Sharif University of Technology, 28 Oct. 2004

Problem D
(Program filename: D.CPP, D.DPR, or D.java)

Software Company
A software developing company has been assigned two programming
projects. As
both projects are within the same contract, both must be handed in at
the same
time. It does not help if one is finished earlier.

This company has n employees to do the jobs. To manage the two
projects more
easily, each is divided into m independent subprojects. Only one
employee can
work on a single subproject at one time, but it is possible for two
employees to
work on different subprojects of the same project simultaneously.

Our goal is to finish the projects as soon as possible.

Input (filename: D.IN)
The first line of the input file contains a single integer t (1 ? t ?
11), the
number of test cases, followed by the input data for each test case.
The first
line of each test case contains two integers n (1 ? n ? 100), and m (1
? m ?
100). The input for this test case will be followed by n lines. Each
line
contains two integers which specify how much time in seconds it will
take for
the specified employee to complete one subproject of each project. So
if the
line contains x and y, it means that it takes the employee x seconds
to complete
a subproject from the first project, and y seconds to complete a
subproject from
the second project.
Output (Standard Output)
There should be one line per test case containing the minimum amount
of time in
seconds after which both projects can be completed.

Sample Input
1
3 20
1 1
2 4
1 6

Sample Output
18

Problem D -Page 1 of 1

29th ACM International Collegiate
Sponsored by
Programming Contest, 2004-2005
Sharif Preliminary Contest
Sharif University of Technology, 28 Oct. 2004
----------------------------------------------------------------------
Problem F
(Program filename: F.CPP, F.DPR, or F.java)

Median Weight Bead
There are N beads which of the same shape and size, but with different
weights.
N is an odd number and the beads are labeled as 1, 2, ..., N. Your
task is to
find the bead whose weight is median (the ((N+1)/2)th among all
beads). The
following comparison has been performed on some pairs of beads:
A scale is given to compare the weights of beads. We can determine
which one is
heavier than the other between two beads. As the result, we now know
that some
beads are heavier than others. We are going to remove some beads which
cannot
have the medium weight.

For example, the following results show which bead is heavier after M
comparisons where M=4 and N=5.

1. Bead 2 is heavier than Bead 1.
2. Bead 4 is heavier than Bead 3.
3. Bead 5 is heavier than Bead 1.
4. Bead 4 is heavier than Bead 2.
>From the above results, though we cannot determine exactly which is
the median
bead, we know that Bead 1 and Bead 4 can never have the median weight:
Beads 2,
4, 5 are heavier than Bead 1, and Beads 1, 2, 3 are lighter than Bead
4.
Therefore, we can remove these two beads.
Write a program to count the number of beads which cannot have the
median
weight.

Input (filename: F.IN)
The first line of the input file contains a single integer t (1 ? t ?
11), the
number of test cases, followed by the input data for each test case.
The input
for each test case will be as follows:
The first line of input data contains an integer N (1=N=99) denoting
the number
of beads, and M denoting the number of pairs of beads compared. In
each of the
next M lines, two numbers are given where the first bead is heavier
than the
second bead.
Output (Standard Output)
There should be one line per test case. Print the number of beads
which can
never have the medium weight.

Sample Input Sample Output
1 2
5 4
2 1
4 3
5 1
4 2
Problem F -Page 1 of 2


From david at pythontoo.com  Sun Jul 12 18:30:12 2009
From: david at pythontoo.com (David)
Date: Sun, 12 Jul 2009 18:30:12 -0400
Subject: Webcam + GStreamer
In-Reply-To: <1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>
Message-ID: <4A5A63F4.6010301@pythontoo.com>

Sparky wrote:
> On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
>> Hello! I need to stream from a webcam in Linux and I need to be able
>> to analyze the video feed frame by frame with PIL. Currently my web-
>> cam (Quickcam Chat) only seems to work with GStreamer so a solution
>> using pygst would be preferred.
>>
>> Thanks for your help,
>> Sam
> 
> Sorry, to clarify I am just having a hard time capturing frames in a
> way that I can access with PIL.

Most web cams produce jpeg images so read the note at the bottom here;
http://effbot.org/imagingbook/format-jpeg.htm
What exactly are you trying to do? What have you tried so far and what 
happened may help.

-- 
Powered by Gentoo GNU/Linux
http://linuxcrazy.com


From ptmcg at austin.rr.com  Sun Jul 12 18:46:05 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Sun, 12 Jul 2009 15:46:05 -0700 (PDT)
Subject: c++ Source Code for acm 2004-2005 problems
References: <03d25e16-97d2-4b09-8113-5011c0e0ded9@p28g2000vbn.googlegroups.com>
Message-ID: <f4411a3f-d980-48cc-b9ea-34203b833f4c@o36g2000vbl.googlegroups.com>

On Jul 12, 5:24?pm, Davood Vahdati <davoodvahdati2... at gmail.com>
wrote:
> Dear Sirs And Madams :
>
> it is an Acm programming competition Questions in year 2004-2005 .
> could you please solve problems is question ? I ?Wan't C++ Source Code
> program About this questions OR Problems . thank you for your prompt
> attention to this matter
>
> 2 1
> 4 3
> 5 1
> 4 2
>
<huge chunk of OT content snipped>

looking for the Python content in this post...

mmmmm, nope, didn't find any...

I guess the OP tried on a C++ newsgroup and got told to do his own
homework, so he came here instead?


From gagsl-py2 at yahoo.com.ar  Sun Jul 12 19:13:43 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 12 Jul 2009 20:13:43 -0300
Subject: c++ Source Code for acm 2004-2005 problems
References: <03d25e16-97d2-4b09-8113-5011c0e0ded9@p28g2000vbn.googlegroups.com>
Message-ID: <op.uwy9g5acx6zn5v@gabriel.sleipnir-bsas>

En Sun, 12 Jul 2009 19:24:57 -0300, Davood Vahdati  
<davoodvahdati2009 at gmail.com> escribi?:

> it is an Acm programming competition Questions in year 2004-2005 .
> could you please solve problems is question ? I  Wan't C++ Source Code
> program About this questions OR Problems . thank you for your prompt
> attention to this matter

Not C++ code but Python: A brute force approach to the first problem.

> Parallelogram Counting
> There are n distinct points in the plane, given by their integer
> coordinates. Find the number of parallelograms whose
> vertices lie on these points.

class Point:
   def __init__(self, x, y): self.x, self.y = x, y
   def __repr__(self): return 'Point(%d,%d)' % (self.x, self.y)

class Segment:
   def __init__(self, p0, p1): self.p0, self.p1 = p0, p1
   def is_parallel(self, other):
     return ((self.p1.x-self.p0.x) * (other.p1.y-other.p0.y) -
             (self.p1.y-self.p0.y) * (other.p1.x-other.p0.x) == 0)

points = [
     Point(-2,-1),
     Point(8,9),
     Point(5,7),
     Point(1,1),
     Point(4,8),
     Point(2,0),
     Point(9,8)]

n = 0
for i,A in enumerate(points):
   for B in points[i+1:]:
     AB = Segment(A,B)
     for C in points:
       if C in (A,B): continue
       BC = Segment(B,C)
       for D in points:
         if D in (A,B,C): continue
         CD = Segment(C,D)
         if AB.is_parallel(CD) and BC.is_parallel(Segment(A,D)):
           print A,B,C,D
           n += 1

n /= 4 # ABCD,BCDA,CDAB,DABC ## BACD etc already removed
print n

-- 
Gabriel Genellina



From clp2 at rebertia.com  Sun Jul 12 19:52:06 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 12 Jul 2009 16:52:06 -0700
Subject: multiprocessing and dictionaries
In-Reply-To: <200907121116.13828.bjorn.m.meyer@gmail.com>
References: <200907121116.13828.bjorn.m.meyer@gmail.com>
Message-ID: <50697b2c0907121652j6cf27749xffd6057a3e01f7c@mail.gmail.com>

On Sun, Jul 12, 2009 at 10:16 AM, Bjorn Meyer<bjorn.m.meyer at gmail.com> wrote:
> I am trying to convert a piece of code that I am using the thread module with
> to the multiprocessing module.
>
> The way that I have it set up is a chunk of code reads a text file and assigns
> a dictionary key multiple values from the text file. I am using locks to write
> the values to the dictionary.
> The way that the values are written is as follows:
> ? ? ? ?mydict.setdefault(key, []).append(value)
>
> The problem that I have run into is that using multiprocessing, the key gets
> set, but the values don't get appended.

Don't have much concurrency experience, but have you tried using a
defaultdict instead?
It's possible its implementation might solve the problem.
http://docs.python.org/dev/library/collections.html#collections.defaultdict

Cheers,
Chris
-- 
http://blog.rebertia.com


From Samnsparky at gmail.com  Sun Jul 12 20:01:55 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 17:01:55 -0700 (PDT)
Subject: Webcam + GStreamer
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com> 
	<mailman.3040.1247437820.8015.python-list@python.org>
Message-ID: <4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>

On Jul 12, 4:30?pm, David <da... at pythontoo.com> wrote:
> Sparky wrote:
> > On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
> >> Hello! I need to stream from a webcam in Linux and I need to be able
> >> to analyze the video feed frame by frame with PIL. Currently my web-
> >> cam (Quickcam Chat) only seems to work with GStreamer so a solution
> >> using pygst would be preferred.
>
> >> Thanks for your help,
> >> Sam
>
> > Sorry, to clarify I am just having a hard time capturing frames in a
> > way that I can access with PIL.
>
> Most web cams produce jpeg images so read the note at the bottom here;http://effbot.org/imagingbook/format-jpeg.htm
> What exactly are you trying to do? What have you tried so far and what
> happened may help.
>
> --
> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com

Dear David,

Thank you for your quick response. I have tried a few things. First of
all, I have tried gst-launch-0.10 v4l2src ! ffmpegcolorspace !
pngenc ! filesink location=foo.png. Foo.png comes out sharp enough but
it takes around 2 seconds to complete. I have also tried CVTypes but
it does not run without LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so and,
when it does run, it only displays colored "snow". Here is that code:

import pygame
import Image
from pygame.locals import *
import sys

import opencv
#this is important for capturing/displaying images
from opencv import highgui

camera = highgui.cvCreateCameraCapture(-1)
print "cam:" + str(camera)
def get_image():
	print "here"
	im = highgui.cvQueryFrame(camera)
	#convert Ipl image to PIL image
	return opencv.adaptors.Ipl2PIL(im)

fps = 30.0
pygame.init()
window = pygame.display.set_mode((320,240))
pygame.display.set_caption("WebCam Demo")
screen = pygame.display.get_surface()

while True:
	events = pygame.event.get()
	im = get_image()
	print im.mode
	pg_img = pygame.image.frombuffer(im.tostring(), im.size, im.mode)
	screen.blit(pg_img, (0,0))
	pygame.display.flip()
	pygame.time.delay(int(1000 * 1.0/fps))

Finally, I have gotten pygst to stream video with the example at
http://pygstdocs.berlios.de/pygst-tutorial/webcam-viewer.html but of
course I do not know how to get a hold of that data. Just so you know,
I am trying a primitive type of object tracking. I would use some of
the libraries already available but the two more popular
implementations on Linux (tbeta/ccv and reacTIVision) dont seem to
work with my web cam. I have more info on those non-python attempts at
http://ubuntuforums.org/showthread.php?p=7596908. Unfortunately no one
seemed to respond to that post.

Thanks again,
Sam


From half.italian at gmail.com  Sun Jul 12 20:03:32 2009
From: half.italian at gmail.com (Sean DiZazzo)
Date: Sun, 12 Jul 2009 17:03:32 -0700 (PDT)
Subject: shutil.rmtree raises "OSError: [Errno 39] Directory not empty" 
	exception
References: <9C99FA09-CEE5-4D05-AD92-6F6D42B0EFE0@usc.edu> 
	<mailman.2994.1247271008.8015.python-list@python.org>
Message-ID: <f495ad53-acee-4604-9ccb-2dad18592d86@o9g2000prg.googlegroups.com>

On Jul 10, 5:10?pm, Tim Chase <python.l... at tim.thechases.com> wrote:
> > ? ? ?shutil.rmtree(filename)
> > ? ?File "/usr/lib64/python2.5/shutil.py", line 178, in rmtree
> > ? ? ?onerror(os.rmdir, path, sys.exc_info())
> > ? ?File "/usr/lib64/python2.5/shutil.py", line 176, in rmtree
> > ? ? ?os.rmdir(path)
> > OSError: [Errno 39] Directory not empty: /path/to/my/dir
>
> > According to the documentation, shutil.rmtree should not care about ?
> > directory being not empty.
>
> This sounds suspiciously like a permission issue. ?rmtree()
> *should* walk the tree removing items *if it can*. ?If a file
> can't be deleted, it treats it as an error. ?rmtree() takes
> parameters for ignore_errors and an onerror callback function, so
> you can catch these error conditions.
>
> -tkc

This one took me a long time to find a solution for.  Check this page,
and see comment #3: http://code.activestate.com/recipes/193736/

I guess if the file is marked as "Read Only" or "Archive", or
whatever, it cannot be deleted with shutil.rmtree()

The key:  win32api.SetFileAttributes(path,
win32con.FILE_ATTRIBUTE_NORMAL)

It will work!

~Sean


From tjreedy at udel.edu  Sun Jul 12 20:15:00 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 12 Jul 2009 20:15:00 -0400
Subject: Question about generators
In-Reply-To: <7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>	<4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
Message-ID: <h3dua1$l12$2@ger.gmane.org>

Cameron Pulsford wrote:

When you start a new thread, you should start a new thread and not 
piggyback on an existing thread.



From cameron.pulsford at gmail.com  Sun Jul 12 21:24:29 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Sun, 12 Jul 2009 21:24:29 -0400
Subject: Question about generators
In-Reply-To: <h3dua1$l12$2@ger.gmane.org>
References: <4A59E7CB.5020908@gmail.com>	<mailman.3030.1247406441.8015.python-list@python.org>	<m2fxd1522x.fsf@cs.uu.nl>	<4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
Message-ID: <B7472107-5B71-4661-891D-3B93DB4EF674@gmail.com>

itertools.chain() did it, thanks!

As far as the primes generator, it does not generate any non-primes.  
All primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5)  
where is x is [1, 2, ..., n]. The only time it doesn't generate a  
prime is when x + (1 or 5) % 5 == 0. Which is what that last part is  
making sure doesn't happen. I'm not a mathematician or anything so  
correct me if I'm wrong, but that's what I've read.

Also sorry if this was piggy backed, I started the thread as a fresh e- 
mail to python-list at python.org, sorry if I messed something up!

On Jul 12, 2009, at 8:15 PM, Terry Reedy wrote:

> Cameron Pulsford wrote:
>
> When you start a new thread, you should start a new thread and not  
> piggyback on an existing thread.
>
> -- 
> http://mail.python.org/mailman/listinfo/python-list



From david at pythontoo.com  Sun Jul 12 21:38:43 2009
From: david at pythontoo.com (David)
Date: Sun, 12 Jul 2009 21:38:43 -0400
Subject: Webcam + GStreamer
In-Reply-To: <4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com>
	<mailman.3040.1247437820.8015.python-list@python.org>
	<4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>
Message-ID: <4A5A9023.8070600@pythontoo.com>

Sparky wrote:
> On Jul 12, 4:30 pm, David <da... at pythontoo.com> wrote:
>> Sparky wrote:
>>> On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
>>>> Hello! I need to stream from a webcam in Linux and I need to be able
>>>> to analyze the video feed frame by frame with PIL. Currently my web-
>>>> cam (Quickcam Chat) only seems to work with GStreamer so a solution
>>>> using pygst would be preferred.
>>>> Thanks for your help,
>>>> Sam
>>> Sorry, to clarify I am just having a hard time capturing frames in a
>>> way that I can access with PIL.
>> Most web cams produce jpeg images so read the note at the bottom here;http://effbot.org/imagingbook/format-jpeg.htm
>> What exactly are you trying to do? What have you tried so far and what
>> happened may help.
>>
>> --
>> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com
> 
> Dear David,
> 
> Thank you for your quick response. I have tried a few things. First of
> all, I have tried gst-launch-0.10 v4l2src ! ffmpegcolorspace !
> pngenc ! filesink location=foo.png. Foo.png comes out sharp enough but
> it takes around 2 seconds to complete. I have also tried CVTypes but
> it does not run without LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so and,
> when it does run, it only displays colored "snow". Here is that code:
> 
> import pygame
> import Image
> from pygame.locals import *
> import sys
> 
> import opencv
> #this is important for capturing/displaying images
> from opencv import highgui
> 
> camera = highgui.cvCreateCameraCapture(-1)
> print "cam:" + str(camera)
> def get_image():
> 	print "here"
> 	im = highgui.cvQueryFrame(camera)
> 	#convert Ipl image to PIL image
> 	return opencv.adaptors.Ipl2PIL(im)
> 
> fps = 30.0
> pygame.init()
> window = pygame.display.set_mode((320,240))
> pygame.display.set_caption("WebCam Demo")
> screen = pygame.display.get_surface()
> 
> while True:
> 	events = pygame.event.get()
> 	im = get_image()
> 	print im.mode
> 	pg_img = pygame.image.frombuffer(im.tostring(), im.size, im.mode)
> 	screen.blit(pg_img, (0,0))
> 	pygame.display.flip()
> 	pygame.time.delay(int(1000 * 1.0/fps))
> 
> Finally, I have gotten pygst to stream video with the example at
> http://pygstdocs.berlios.de/pygst-tutorial/webcam-viewer.html but of
> course I do not know how to get a hold of that data. Just so you know,
> I am trying a primitive type of object tracking. I would use some of
> the libraries already available but the two more popular
> implementations on Linux (tbeta/ccv and reacTIVision) dont seem to
> work with my web cam. I have more info on those non-python attempts at
> http://ubuntuforums.org/showthread.php?p=7596908. Unfortunately no one
> seemed to respond to that post.
> 
> Thanks again,
> Sam
See if this gets you started, I got it working here with a video4linux2 cam.
http://code.google.com/p/python-video4linux2/
here is what I have, I think it is the same;
http://dwabbott.com/python-video4linux2-read-only/
let me know how you make out.
-david


-- 
Powered by Gentoo GNU/Linux
http://linuxcrazy.com


From drobinow at gmail.com  Sun Jul 12 22:00:15 2009
From: drobinow at gmail.com (David Robinow)
Date: Sun, 12 Jul 2009 22:00:15 -0400
Subject: Question about generators
In-Reply-To: <B7472107-5B71-4661-891D-3B93DB4EF674@gmail.com>
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
	<B7472107-5B71-4661-891D-3B93DB4EF674@gmail.com>
Message-ID: <4eb0089f0907121900o3f8f3416vd519c1487465fb1a@mail.gmail.com>

On Sun, Jul 12, 2009 at 9:24 PM, Cameron
Pulsford<cameron.pulsford at gmail.com> wrote:
> As far as the primes generator, it does not generate any non-primes. All
> primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5) where is x is
> [1, 2, ..., n]. The only time it doesn't generate a prime is when x + (1 or
> 5) % 5 == 0. Which is what that last part is making sure doesn't happen. I'm
> not a mathematician or anything so correct me if I'm wrong, but that's what
> I've read.
 All you're doing is eliminating numbers divisible by 2,3, and 5.
Your generator includes   49  (7 * 7),  77 (7*11), 91 (7*13), 121 (11*11),  etc.


From sjmachin at lexicon.net  Sun Jul 12 22:26:20 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 12 Jul 2009 19:26:20 -0700 (PDT)
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org> 
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org> 
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org> 
	<mailman.3044.1247448559.8015.python-list@python.org>
Message-ID: <0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>

On Jul 13, 11:24?am, Cameron Pulsford <cameron.pulsf... at gmail.com>
wrote:

> As far as the primes generator, it does not generate any non-primes. ?
> All primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5) ?
> where is x is [1, 2, ..., n]. The only time it doesn't generate a ?
> prime is when x + (1 or 5) % 5 == 0. Which is what that last part is ?
> making sure doesn't happen. I'm not a mathematician or anything so
> correct me if I'm wrong, but that's what I've read.

Where did you read that? Have you tried to verify it, like this:

| >>> [6*i+j for i in range(1, 21) for j in (1, 5) if (i+j) % 5]
| [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67,
71, 73, 77, 79, 83, 89, 91, 97, 101, 103, 107, 109, 113, 119, 121]

49, 77, 91, and 121 are not prime.



From Samnsparky at gmail.com  Sun Jul 12 22:54:21 2009
From: Samnsparky at gmail.com (Sparky)
Date: Sun, 12 Jul 2009 19:54:21 -0700 (PDT)
Subject: Webcam + GStreamer
References: <403834a0-de07-47b2-8529-1a84e26c321a@x6g2000prc.googlegroups.com>
	<1b905fc1-5066-421e-8f5e-3162b95c1f3c@v15g2000prn.googlegroups.com> 
	<mailman.3040.1247437820.8015.python-list@python.org>
	<4c9114cd-3a0a-4959-9f21-538115a3a8bc@g7g2000prg.googlegroups.com>
	<mailman.3045.1247449441.8015.python-list@python.org>
Message-ID: <8aac1115-3dcc-4e91-94d6-ac4204879420@d9g2000prh.googlegroups.com>

On Jul 12, 7:38?pm, David <da... at pythontoo.com> wrote:
> Sparky wrote:
> > On Jul 12, 4:30 pm, David <da... at pythontoo.com> wrote:
> >> Sparky wrote:
> >>> On Jul 12, 3:50 pm, Sparky <Samnspa... at gmail.com> wrote:
> >>>> Hello! I need to stream from a webcam in Linux and I need to be able
> >>>> to analyze the video feed frame by frame with PIL. Currently my web-
> >>>> cam (Quickcam Chat) only seems to work with GStreamer so a solution
> >>>> using pygst would be preferred.
> >>>> Thanks for your help,
> >>>> Sam
> >>> Sorry, to clarify I am just having a hard time capturing frames in a
> >>> way that I can access with PIL.
> >> Most web cams produce jpeg images so read the note at the bottom here;http://effbot.org/imagingbook/format-jpeg.htm
> >> What exactly are you trying to do? What have you tried so far and what
> >> happened may help.
>
> >> --
> >> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com
>
> > Dear David,
>
> > Thank you for your quick response. I have tried a few things. First of
> > all, I have tried gst-launch-0.10 v4l2src ! ffmpegcolorspace !
> > pngenc ! filesink location=foo.png. Foo.png comes out sharp enough but
> > it takes around 2 seconds to complete. I have also tried CVTypes but
> > it does not run without LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so and,
> > when it does run, it only displays colored "snow". Here is that code:
>
> > import pygame
> > import Image
> > from pygame.locals import *
> > import sys
>
> > import opencv
> > #this is important for capturing/displaying images
> > from opencv import highgui
>
> > camera = highgui.cvCreateCameraCapture(-1)
> > print "cam:" + str(camera)
> > def get_image():
> > ? ?print "here"
> > ? ?im = highgui.cvQueryFrame(camera)
> > ? ?#convert Ipl image to PIL image
> > ? ?return opencv.adaptors.Ipl2PIL(im)
>
> > fps = 30.0
> > pygame.init()
> > window = pygame.display.set_mode((320,240))
> > pygame.display.set_caption("WebCam Demo")
> > screen = pygame.display.get_surface()
>
> > while True:
> > ? ?events = pygame.event.get()
> > ? ?im = get_image()
> > ? ?print im.mode
> > ? ?pg_img = pygame.image.frombuffer(im.tostring(), im.size, im.mode)
> > ? ?screen.blit(pg_img, (0,0))
> > ? ?pygame.display.flip()
> > ? ?pygame.time.delay(int(1000 * 1.0/fps))
>
> > Finally, I have gotten pygst to stream video with the example at
> >http://pygstdocs.berlios.de/pygst-tutorial/webcam-viewer.htmlbut of
> > course I do not know how to get a hold of that data. Just so you know,
> > I am trying a primitive type of object tracking. I would use some of
> > the libraries already available but the two more popular
> > implementations on Linux (tbeta/ccv and reacTIVision) dont seem to
> > work with my web cam. I have more info on those non-python attempts at
> >http://ubuntuforums.org/showthread.php?p=7596908. Unfortunately no one
> > seemed to respond to that post.
>
> > Thanks again,
> > Sam
>
> See if this gets you started, I got it working here with a video4linux2 cam.http://code.google.com/p/python-video4linux2/
> here is what I have, I think it is the same;http://dwabbott.com/python-video4linux2-read-only/
> let me know how you make out.
> -david
>
> --
> Powered by Gentoo GNU/Linuxhttp://linuxcrazy.com

I gave it a shot and here is what I got:

sam at sam-laptop:~/python-video4linux2-read-only$ ./pyv4l2.py
Available devices:  ['/dev/video0']
	/dev/video0
Capabilities:
	Capture
	ReadWrite
	Streaming
Input 0:
		Name:	zc3xx
		Type:	camera
		Standards: []
Pixel formats:
	JPEG	JPEG
Resolutions:
Segmentation fault

-------------------------------------

sam at sam-laptop:~/python-video4linux2-read-only$ ./streampics.py /dev/
video0 0 BGR3 640 480 testpics
Trying to create directory pics
Recording /dev/video0:0 with format JPEG at (640, 480)
Traceback (most recent call last):
  File "./streampics.py", line 94, in <module>
    Run()
  File "./streampics.py", line 78, in Run
    d.SetupStreaming(5, StreamCallback)
  File "/home/sam/python-video4linux2-read-only/pyv4l2.py", line 682,
in SetupStreaming
    self.StreamOn()
  File "/home/sam/python-video4linux2-read-only/pyv4l2.py", line 636,
in StreamOn
    lib.Error()
Exception: Could not start streaming:	22: Invalid argument
*** glibc detected *** python: free(): invalid next size (fast):
0x0a2aeff0 ***

Any suggestions?

Thanks,
Sam


From cameron.pulsford at gmail.com  Sun Jul 12 23:17:31 2009
From: cameron.pulsford at gmail.com (Cameron Pulsford)
Date: Sun, 12 Jul 2009 23:17:31 -0400
Subject: Question about generators
In-Reply-To: <0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
	<mailman.3044.1247448559.8015.python-list@python.org>
	<0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
Message-ID: <BEC2887C-8E6F-4FBB-A723-257AF19C6C3E@gmail.com>

I read it on the haskell site in their sieves/prime wheel section, I  
guess I misunderstood something. (east to do over there...) I did  
verify it against established list of primes and other generators I've  
written that use more normal methods, but I only hand verified it.

It is at least interesting though, I can probably extend it to check  
for primality by using a more normal sieve method. It might be pretty  
fast too because generally it does only generate primes, and the few  
non primes it does generate could be caught quickly using a scratching  
out technique.

When I was initially looking at it there are some interesting patterns  
I might be able to extend into a generator that would yield only  
correct sets of numbers for the 6x + n pattern.


On Jul 12, 2009, at 10:26 PM, John Machin wrote:

> On Jul 13, 11:24 am, Cameron Pulsford <cameron.pulsf... at gmail.com>
> wrote:
>
>> As far as the primes generator, it does not generate any non-primes.
>> All primes (except 2, 3 and 5) are in the form (6*x + 1, 6*x + 5)
>> where is x is [1, 2, ..., n]. The only time it doesn't generate a
>> prime is when x + (1 or 5) % 5 == 0. Which is what that last part is
>> making sure doesn't happen. I'm not a mathematician or anything so
>> correct me if I'm wrong, but that's what I've read.
>
> Where did you read that? Have you tried to verify it, like this:
>
> | >>> [6*i+j for i in range(1, 21) for j in (1, 5) if (i+j) % 5]
> | [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67,
> 71, 73, 77, 79, 83, 89, 91, 97, 101, 103, 107, 109, 113, 119, 121]
>
> 49, 77, 91, and 121 are not prime.
>
> -- 
> http://mail.python.org/mailman/listinfo/python-list



From vincent.gulinao at gmail.com  Mon Jul 13 01:06:11 2009
From: vincent.gulinao at gmail.com (Vincent Gulinao)
Date: Mon, 13 Jul 2009 13:06:11 +0800
Subject: Infinite loops and synchronization
Message-ID: <fcc3e6170907122206t59a17747kef305ef79066a6c2@mail.gmail.com>

lst = list()

(lst populated by async twisted deferred callbacks)

while True:
	if len(lst) == SOME_NUMBER:
		return lst

Q1: is this a common OK practice? I'm worried infinite loops hogs memory.
Q2: operating on list from threads (mostly appends) must be safe,
right (synchronization)?


From sjmachin at lexicon.net  Mon Jul 13 01:08:30 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 12 Jul 2009 22:08:30 -0700 (PDT)
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org> 
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org> 
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org> 
	<mailman.3044.1247448559.8015.python-list@python.org>
	<0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
	<mailman.3047.1247455341.8015.python-list@python.org>
Message-ID: <b8ccc8a9-b320-4f5c-b3ea-1be036f2de8f@l5g2000pra.googlegroups.com>

On Jul 13, 1:17?pm, Cameron Pulsford <cameron.pulsf... at gmail.com>
wrote:
> I read it on the haskell site in their sieves/prime wheel section, I ?
> guess I misunderstood something. (east to do over there...) I did ?
> verify it against established list of primes and other generators I've ?
> written that use more normal methods, but I only hand verified it.

"to verify" something means to ensure the truth or correctness, NOT
attempt to ensure ;-)


From amit.kumar.iitr at gmail.com  Mon Jul 13 02:42:02 2009
From: amit.kumar.iitr at gmail.com (Amit)
Date: Sun, 12 Jul 2009 23:42:02 -0700 (PDT)
Subject: compilation problem of python on AIX 6.1
Message-ID: <51c556a8-7277-474d-821f-190adf155c75@f16g2000vbf.googlegroups.com>

Hello

I want to intsall python on my AIX 6.1 Box.
I couldn't get any rpm for python 2.5.x for AIX 6.1.

THen I decided to compile python 2.5.4 on my AIX box. I downloaded the
python source code from www.python.org and tried to compile on my AIX
both using gcc.

step 1 ./configure --with-gcc
configuration runs successfully

step 2 make
it gives me error

	case $MAKEFLAGS in  *-s*)  CC='gcc -pthread' LDSHARED='./Modules/
ld_so_aix gcc -pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -
fwrapv -O3 -Wall -Wstrict-prototypes' ./python -E ./setup.py -q
build;;  *)  CC='gcc -pthread' LDSHARED='./Modules/ld_so_aix gcc -
pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes' ./python -E ./setup.py build;;  esac
running build
running build_ext
building 'bz2' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes -I. -I/avre/Python-2.5.4/./Include -I. -IInclude -
I./Include -I/avre/Python-2.5.4/Include -I/avre/Python-2.5.4 -c /avre/
Python-2.5.4/Modules/bz2module.c -o build/temp.aix-6.1-2.5/avre/
Python-2.5.4/Modules/bz2module.o
building '_tkinter' extension
./Modules/ld_so_aix gcc -pthread -bI:Modules/python.exp build/
temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/_tkinter.o build/
temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/tkappinit.o -L/usr/X11/lib -
ltk8.4 -ltcl8.4 -lX11 -o build/lib.aix-6.1-2.5/_tkinter.so
*** WARNING: renaming "_tkinter" since importing it failed: 	0509-022
Cannot load module build/lib.aix-6.1-2.5.
	0509-026 System error: A file or directory in the path name does not
exist.

plz suggest


From piet at cs.uu.nl  Mon Jul 13 03:56:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 09:56:08 +0200
Subject: multiprocessing and dictionaries
References: <mailman.3031.1247418982.8015.python-list@python.org>
Message-ID: <m2y6qt2ezr.fsf@cs.uu.nl>

>>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:

>BM> I am trying to convert a piece of code that I am using the thread module with 
>BM> to the multiprocessing module.

>BM> The way that I have it set up is a chunk of code reads a text file and assigns 
>BM> a dictionary key multiple values from the text file. I am using locks to write 
>BM> the values to the dictionary.
>BM> The way that the values are written is as follows:
>BM> 	mydict.setdefault(key, []).append(value)

>BM> The problem that I have run into is that using multiprocessing, the key gets 
>BM> set, but the values don't get appended.
>BM> I've even tried the Manager().dict() option, but it doesn't seem to work.

>BM> Is this not supported at this time or am I missing something?

I think you should give more information. Try to make a *minimal* program
that shows the problem and include it in your posting or supply a
download link.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 04:01:53 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 10:01:53 +0200
Subject: Question about generators
References: <4A59E7CB.5020908@gmail.com>
	<mailman.3030.1247406441.8015.python-list@python.org>
	<m2fxd1522x.fsf@cs.uu.nl> <4A5A27E1.1090502@gmail.com>
	<h3db5t$9r9$1@ger.gmane.org>
	<7EA9A678-E06B-481D-9FAB-34957B5F2D01@gmail.com>
	<h3dua1$l12$2@ger.gmane.org>
	<mailman.3044.1247448559.8015.python-list@python.org>
	<0e1441d0-8250-4646-828d-850c201b6725@d4g2000prc.googlegroups.com>
	<mailman.3047.1247455341.8015.python-list@python.org>
Message-ID: <m2tz1h2eq6.fsf@cs.uu.nl>

>>>>> Cameron Pulsford <cameron.pulsford at gmail.com> (CP) wrote:

>CP> I read it on the haskell site in their sieves/prime wheel section,
>CP> I guess I misunderstood something. (east to do over there...) I did
>CP> verify it against established list of primes and other generators
>CP> I've written that use more normal methods, but I only hand verified
>CP> it.

If it is used in a sieve then the non-primes will be sieved out.

>CP> It is at least interesting though, I can probably extend it to
>CP> check for primality by using a more normal sieve method. It might
>CP> be pretty fast too because generally it does only generate primes,
>CP> and the few non primes it does generate could be caught quickly
>CP> using a scratching out technique.

it does only generate primes => it does generate all primes.

>CP> When I was initially looking at it there are some interesting
>CP> patterns I might be able to extend into a generator that would
>CP> yield only correct sets of numbers for the 6x + n pattern.

As I wrote in my previous reply, in your use case the non-primes are
harmless. But it is useful to reflect that in the naming of your
identifiers. 

*And please, don't top post.*

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 04:53:36 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 10:53:36 +0200
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <m2my792cbz.fsf@cs.uu.nl>

>>>>> Vincent Gulinao <vincent.gulinao at gmail.com> (VG) wrote:

>VG> lst = list()
>VG> (lst populated by async twisted deferred callbacks)

>VG> while True:
>VG> 	if len(lst) == SOME_NUMBER:
>VG> 		return lst

>VG> Q1: is this a common OK practice? I'm worried infinite loops hogs memory.
>VG> Q2: operating on list from threads (mostly appends) must be safe,
>VG> right (synchronization)?

I am not familiar enough with twisted, but I think the principle is
independent from twisted.

This loop will not hog memory but it will hog CPU time.

You should use a synchronisation construct like threading.Condition or a
Semaphore. Here is my suggestion with a Condition:

Global somewhere:
       lst_cond = Condition()

In your loop:

lst = list()  # Why not lst = []?

while True: # strange while/if combo
	if len(lst) == SOME_NUMBER:
		return lst

Make that:

with lst_cond:
    while len(lst) < SOME_NUMBER:
        lst_cond.wait()
    return lst

In the callback:

with lst_cond:
    lst.append(new_value)
    lst_cond.notify()

In case you don't have a python that supports the with statement (not
even `from future') you should use:

lst_cond.acquire()
try:
    .....
finally:
    lst_cond.release()

I think the solution with a semaphore is less elegant.

global: sem = Semaphore()

loop:
for i in range(SOME_NUMBER): 
    sem.acquire()
return lst

In callback:

lst.append(new_value)
sem.release()

*Be careful: I haven't tested this code (not even syntax checked). So
consider it pseudo code.*
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From vinay_sajip at yahoo.co.uk  Mon Jul 13 05:39:40 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Mon, 13 Jul 2009 02:39:40 -0700 (PDT)
Subject: the ultimate logging facility for debugging code
References: <mailman.2939.1247218807.8015.python-list@python.org>
Message-ID: <69032a2b-0f8e-4174-b996-6203387c4058@l5g2000vbp.googlegroups.com>

On Jul 10, 10:39?am, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> Greetings,
>
> Sorry for the dubious title :o). I was wandering if there is a standard
> (or reliable) python module that implements the following feature:
>
> http://code.activestate.com/recipes/198078/
> ?>>>Recipe 198078: Wrapping method calls (meta-class example)
> ?>>>
> ?>>>A metaclass is used to wrap all (or just some) methods forlogging
> purposes. The underlying mechanism can be used as well to check pre/post
> conditions, attribute access,... The basic point is, that the actual
> class must not be changed in any way to achive the desired effect.
>
> I had to adapt the code to some of my needs, but now it's almost
> working, by simply defining a metaclass for any of my class, I get the
> class methods calls logged with the instance that called the method, the
> method name, the call line in the file, the parameter **value** ?passed
> to the method and the returned value.
> It just saved me from hours of ipython interactive debugging with the
> old print way, and to beauty of it: I don't have to write any
> "self._log('Please log me')" line.
>
> As it is so useful, I bet there is a module that is doing this in a more
> reliable way that I did. Anyone has heard of it ?
>
> Jean-Michel

Check out the Python Decorator Library: http://wiki.python.org/moin/PythonDecoratorLibrary

and you should be able to adapt what you find there to your needs.

Regards,

Vinay Sajip


From pdpinheiro at gmail.com  Mon Jul 13 06:12:03 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Mon, 13 Jul 2009 03:12:03 -0700 (PDT)
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <c44bae99-b3b8-4130-82d7-f2853302c3ab@f16g2000vbf.googlegroups.com>

On Jul 13, 6:06?am, Vincent Gulinao <vincent.guli... at gmail.com> wrote:
> lst = list()
>
> (lst populated by async twisted deferred callbacks)
>
> while True:
> ? ? ? ? if len(lst) == SOME_NUMBER:
> ? ? ? ? ? ? ? ? return lst
>
> Q1: is this a common OK practice? I'm worried infinite loops hogs memory.
> Q2: operating on list from threads (mostly appends) must be safe,
> right (synchronization)?

Q1: I'll answer your question with another. What's so fundamentally
different between your infinite loop and this one:

while len(lst) != SOME_NUMBER:
  pass
return lst

which is not an "infinite loop"[1]. Why would yours be any worse in
terms of memory than mine? Are you allocating anything that would hog
memory? Of course, like Piet said, it *will* hog your CPU, so you want
a time.sleep(.1) in there, at the least. Of course, the question is:
why aren't you using a semaphore to let you know you can proceed, and
make the provider increment the semaphore?

[1] -- well, it can be, if len(lst) == SOME_NUMBER never comes about,
and I'd hazard a guess that that's pretty much where your fear of
memory hogging comes from: it's easy to allocate stuff and not
deallocate it within a cycle, only to find the bounds on that cycle
going awry.


From ganesh.gbg at gmail.com  Mon Jul 13 06:34:19 2009
From: ganesh.gbg at gmail.com (gganesh)
Date: Mon, 13 Jul 2009 03:34:19 -0700 (PDT)
Subject: simple question about Dictionary type containing  List objects
Message-ID: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>

Hi group,
I have a dict object like
emails={'mycontacts': [ 'xxx at gmail.com, 'yy at gmail.com',
'zz at gmail.com'], 'myname':['gganesh']}
I need to get the lenght of the list mycontacts ,like
mycontacts_numbers=3
help me to solve
Thanks




From contact at xavierho.com  Mon Jul 13 06:36:55 2009
From: contact at xavierho.com (Xavier Ho)
Date: Mon, 13 Jul 2009 18:36:55 +0800
Subject: simple question about Dictionary type containing List objects
In-Reply-To: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>
References: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>
Message-ID: <2d56febf0907130336x6950051em7903f66b5dfc5349@mail.gmail.com>

On Mon, Jul 13, 2009 at 6:34 PM, gganesh <ganesh.gbg at gmail.com> wrote:

> Hi group,
> I have a dict object like
> emails={'mycontacts': [ 'xxx at gmail.com, 'yy at gmail.com',
> 'zz at gmail.com'], 'myname':['gganesh']}
> I need to get the lenght of the list mycontacts ,like
> mycontacts_numbers=3 <http://mail.python.org/mailman/listinfo/python-list>
>

>>> len(emails['mycontacts'])
3

HTH,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/f2807dbb/attachment-0001.html>

From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:22:36 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:22:36 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
	<h3bogf$oo0$1@panix3.panix.com>
Message-ID: <h3f5dt$dld$3@lust.ihug.co.nz>

In message <h3bogf$oo0$1 at panix3.panix.com>, Aahz wrote:

> In article <h3bagu$52m$4 at lust.ihug.co.nz>,
> Lawrence D'Oliveiro  <ldo at geek-central.gen.new_zealand> wrote:
>>In message <h37gv5$r81$1 at panix3.panix.com>, Aahz wrote:
>>>
>>> It helps to remember that names and namespaces are in many
>>> ways syntactic sugar for dicts or lists.
>>
>>Interesting, though, that Python insists on maintaining a distinction
>>between c["x"] and c.x, whereas JavaScript doesn't bother.
> 
> Why do you say "insists"?
> 
> class AttrDict:
>     def __getitem__(self, key):
>         return getattr(self, key)

OK, let's try it:

    >>> c = {}
    >>> c["x"] = 3
    >>> c.x = 4   
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    AttributeError: 'dict' object has no attribute 'x'
    >>> class AttrDict:
    ...     def __getitem__(self, key):
    ...         return getattr(self, key)
    ...
    >>> c.x = 4
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    AttributeError: 'dict' object has no attribute 'x'

Nope, still doesn't work...



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:24:03 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:24:03 +1200
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <h3f5gj$dld$4@lust.ihug.co.nz>

In message <mailman.3048.1247462046.8015.python-list at python.org>, Vincent 
Gulinao wrote:

> Q1: is this a common OK practice? I'm worried infinite loops hogs memory.

The problem is not that the loop is infinite, but that it busy-waits, 
hogging CPU.



From eckhardt at satorlaser.com  Mon Jul 13 07:25:29 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Mon, 13 Jul 2009 13:25:29 +0200
Subject: simple question about Dictionary type containing  List objects
References: <2c98a9f3-b84c-4d92-8458-0da061e5b26d@v37g2000prg.googlegroups.com>
Message-ID: <96iri6-s13.ln1@satorlaser.homedns.org>

gganesh wrote:
> I have a dict object like
> emails={'mycontacts': [ 'xxx at gmail.com, 'yy at gmail.com',
> 'zz at gmail.com'], 'myname':['gganesh']}
> I need to get the lenght of the list mycontacts ,like
> mycontacts_numbers=3

mycontacts = emails['mycontacts']
mycontacts_number = len(mycontacts)

A list doesn't change in behaviour when it is contained in a dictionary.

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:27:33 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:27:33 +1200
Subject: MySQLdb + SSH Tunnel
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
	<mailman.3035.1247427709.8015.python-list@python.org>
Message-ID: <h3f5n5$dld$5@lust.ihug.co.nz>

In message <mailman.3035.1247427709.8015.python-list at python.org>, Emile van 
Sebille wrote:

> ssh with something like...
> 
> ssh -lroot -L3306:C:3306 B
> 
> Watch out for other instances of mysql on A or B...

You can use a non-default local port and specify that in your local 
connection parameters. Similarly you can tell the remote server to use a 
non-default port in its /etc/my.cnf.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:29:39 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:29:39 +1200
Subject: Looking for a tool to checkfor python script backward
	compatibility
References: <4a59951a$0$10853$426a74cc@news.free.fr>
Message-ID: <h3f5r3$dld$6@lust.ihug.co.nz>

In message <4a59951a$0$10853$426a74cc at news.free.fr>, Baptiste Lepilleur 
wrote:

> I'm looking for a tool that could be used in a pre-commit step to check
> that only features available in a "old" python version are used, say
> python 2.3 for example.

The only sure way would be to run the script under an appropriately old 
version of Python.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:35:43 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:35:43 +1200
Subject: send keys to focused window
References: <MPG.24c0392b71e8a0eb989680@news.bintube.com>
Message-ID: <h3f66f$dld$7@lust.ihug.co.nz>

In message <MPG.24c0392b71e8a0eb989680 at news.bintube.com>, Broken wrote:

> I am new to Python, and I'm miserably failing to send specific keys to
> (say) notepad.

I don't understand why you need to automate a GUI front-end, meant for human
use, to a function that can be directly performed without that front-end
anyway.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:37:09 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:37:09 +1200
Subject: Check file is locked?
References: <e0b6c39a0907071231g32c8a8bq8942bf9a370edeb2@mail.gmail.com>
	<mailman.2795.1246997268.8015.python-list@python.org>
	<h30ndf$vho$1@lust.ihug.co.nz>
	<e33f92de-a565-4f5f-a29e-9e73d9fecdd3@p36g2000prn.googlegroups.com>
	<mailman.2827.1247039136.8015.python-list@python.org>
	<a6b08d52-08c7-4567-8102-38c8b0348104@d9g2000prh.googlegroups.com>
	<mailman.2874.1247127660.8015.python-list@python.org>
	<a6b7375f-19c6-4182-b46e-110785c2a764@y4g2000prf.googlegroups.com>
	<mailman.2880.1247134886.8015.python-list@python.org>
	<652cca82-44a3-473f-b640-c2336a9cf929@v15g2000prn.googlegroups.com>
Message-ID: <h3f695$dld$8@lust.ihug.co.nz>

In message <652cca82-44a3-473f-b640-
c2336a9cf929 at v15g2000prn.googlegroups.com>, Rajat wrote:

> ... my whole idea is to close the wordpad / notepad application so that I
> can delete the file and the directory where this file resides.

Don't you think the user might have that application open for a reason?



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:39:34 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:39:34 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<4a538a71$0$30236$9b4e6d93@newsspool1.arcor-online.net>
Message-ID: <h3f6dn$dld$9@lust.ihug.co.nz>

In message <4a538a71$0$30236$9b4e6d93 at newsspool1.arcor-online.net>, Stefan 
Behnel wrote:

> Lawrence D'Oliveiro wrote:
>>
>> I wonder how many people have been tripped up by the fact that
>> 
>>     ++n
>> 
>> and
>> 
>>     --n
>> 
>> fail silently for numeric-valued n.
> 
> I doubt that there are many. Plus, you misspelled them from the more
> obvious
> 
> n++
> 
> and
> 
> n--
> 
> which *do* fail with a SyntaxError.

Funny, you accuse me of "misspelling", when it's _your_ version that fails 
with errors!



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:44:32 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:44:32 +1200
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<006da5a2$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2746.1246935242.8015.python-list@python.org>
	<4a531512$0$9355$426a74cc@news.free.fr>
	<fbe2e2100907070929i1e0062abraa0e4c62fd1fc148@mail.gmail.com>
	<mailman.2787.1246986627.8015.python-list@python.org>
Message-ID: <h3f6n0$dld$10@lust.ihug.co.nz>

In message <mailman.2787.1246986627.8015.python-list at python.org>, MRAB 
wrote:

> I wonder whether the problem with assignment in conditionals in C is due
> to the assignment operator being "=". If it was ":=", would the error
> still occur?

One of the original C designers, Kernighan or Ritchie, admitted that he made 
the assignment operator "=" instead of ":=" just to save typing one 
character, because he thought assignments were more common than tests for 
equality.



From ldo at geek-central.gen.new_zealand  Mon Jul 13 07:47:10 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Mon, 13 Jul 2009 23:47:10 +1200
Subject: Blocking XMPP API?
References: <mailman.2893.1247147391.8015.python-list@python.org>
Message-ID: <h3f6ru$dld$11@lust.ihug.co.nz>

In message <mailman.2893.1247147391.8015.python-list at python.org>, Gabriel 
Rossetti wrote:

> I am looking for blocking XMPP API. I'm wanting to make a webservice
> that uses XMPP, but all the XMPP libs I find are non-blocking (i.e. w/
> callbacks).

So why not have the caller sleep or something until the callback is invoked?

It's easier to turn an async API into a synchronous one than the other way 
round.



From piet at cs.uu.nl  Mon Jul 13 08:15:07 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 14:15:07 +0200
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
	<h3bogf$oo0$1@panix3.panix.com> <h3f5dt$dld$3@lust.ihug.co.nz>
Message-ID: <m24otg3hkk.fsf@cs.uu.nl>

>>>>> Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> (LD) wrote:

>LD> In message <h3bogf$oo0$1 at panix3.panix.com>, Aahz wrote:

>Aahz> class AttrDict:
>Aahz> def __getitem__(self, key):
>Aahz> return getattr(self, key)

>LD> OK, let's try it:

>LD> >>> c = {}
>LD> >>> c["x"] = 3
>LD> >>> c.x = 4   
>LD>     Traceback (most recent call last):
>LD>       File "<stdin>", line 1, in <module>
>LD>     AttributeError: 'dict' object has no attribute 'x'
>LD> >>> class AttrDict:
>LD>     ...     def __getitem__(self, key):
>LD>     ...         return getattr(self, key)
>LD>     ...
>LD> >>> c.x = 4
>LD>     Traceback (most recent call last):
>LD>       File "<stdin>", line 1, in <module>
>LD>     AttributeError: 'dict' object has no attribute 'x'

>LD> Nope, still doesn't work...

Of course you need c = AttrDict()

And to get c.x = 4 working you also need a __setitem__. 
And to get c["x"] working AtrrDict should subclass dict:

>>> class AttrDict(dict):

but these are only minor details :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From dzizes451 at gmail.com  Mon Jul 13 09:07:52 2009
From: dzizes451 at gmail.com (dzizes)
Date: Mon, 13 Jul 2009 06:07:52 -0700 (PDT)
Subject: how to set timeout while colling a soap method?
Message-ID: <24461403.post@talk.nabble.com>


Hello!

I wrote some some python code for executing a soap method:

import SOAPpy
from SOAPpy import WSDL

_server = WSDL.Proxy(some wsdl)
r=_server.generuj(some parameters...)
print r.encode('cp1250')

It works fine. However, the execution time of this soap method might be
long. Therefore, I would like to set a timeout like 1 minute, after which I
would post a timeoute message.

Any ideas?
Greats,


-- 
View this message in context: http://www.nabble.com/how-to-set-timeout-while-colling-a-soap-method--tp24461403p24461403.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From denis-bz-gg at t-online.de  Mon Jul 13 09:11:09 2009
From: denis-bz-gg at t-online.de (denis)
Date: Mon, 13 Jul 2009 06:11:09 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
Message-ID: <07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>

Matt, how many words are you looking for, in how long a string ?
Were you able to time any( substr in long_string ) against re.compile
( "|".join( list_items )) ?
(REs are my method of choice, but different inputs of course give
different times --
see google regex speed site:groups.google.com /
site:stackoverflow.com .)

cheers
  -- denis




From seldan24 at gmail.com  Mon Jul 13 09:26:19 2009
From: seldan24 at gmail.com (seldan24)
Date: Mon, 13 Jul 2009 06:26:19 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
Message-ID: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>

Hello,

I'm fairly new at Python so hopefully this question won't be too
awful.  I am writing some code that will FTP to a host, and want to
catch any exception that may occur, take that and print it out
(eventually put it into a log file and perform some alerting action).
I've figured out two different ways to do this, and am wondering which
is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
to understand exactly what occurs for each one.

The first example:

from ftplib import FTP
try:
    ftp = FTP(ftp_host)
    ftp.login(ftp_user, ftp_pass)
except Exception, err:
    print err

This works fine.  I read through the documentation, and my
understanding is that there is a built-in exceptions module in python,
that is automatically available in a built-in namespace.  Within that
module is an 'Exception' class which would contain whatever exception
is thrown.  So, I'm passing that to the except, along with err to hold
the value and then print it out.

The second example:

from ftplib import FTP
import sys
try:
    ftp = FTP(ftp_host)
    ftp.login(ftp_user, ftp_pass)
except:
    print sys.exc_info()

Here I, for the most part, get the same thing.  I'm not passing
anything to except and just printing out the exception using a method
defined in the sys module.

So, I'm new to Python... I've made it this far and am happy, but want
to make sure I'm coding correctly from the start.  Which method is the
better/cleaner/more standard way to continue?  Thanks for any help.


From dsdale24 at gmail.com  Mon Jul 13 09:38:17 2009
From: dsdale24 at gmail.com (Darren Dale)
Date: Mon, 13 Jul 2009 06:38:17 -0700 (PDT)
Subject: Is it possible to use keyword arguments from C?
Message-ID: <94892b60-b4cb-40fc-8c9d-7cfb7d1c00ed@q35g2000vbi.googlegroups.com>

I am learning about the python C-api in order to contribute a feature
to numpy. I see a discussion (http://docs.python.org/extending/
extending.html#keyword-parameters-for-extension-functions) on how to
create a function or method  in C that accepts kwargs, but is it
possible to call such a method from C using kwargs rather than
positional arguments?


From dsdale24 at gmail.com  Mon Jul 13 09:47:41 2009
From: dsdale24 at gmail.com (Darren Dale)
Date: Mon, 13 Jul 2009 06:47:41 -0700 (PDT)
Subject: Is it possible to use keyword arguments from C?
References: <94892b60-b4cb-40fc-8c9d-7cfb7d1c00ed@q35g2000vbi.googlegroups.com>
Message-ID: <29a66e7b-1263-4c06-ab01-017b471d53d1@p36g2000vbn.googlegroups.com>

On Jul 13, 9:38?am, Darren Dale <dsdal... at gmail.com> wrote:
> I am learning about the python C-api in order to contribute a feature
> to numpy. I see a discussion (http://docs.python.org/extending/
> extending.html#keyword-parameters-for-extension-functions) on how to
> create a function or method ?in C that accepts kwargs, but is it
> possible to call such a method from C using kwargs rather than
> positional arguments?

The answer was yes, this can be done. I found a short discussion at
the bottom of section 1.6: http://docs.python.org/extending/extending.html#calling-python-functions-from-c


From tonylay at gmail.com  Mon Jul 13 09:57:29 2009
From: tonylay at gmail.com (Tony Lay)
Date: Mon, 13 Jul 2009 06:57:29 -0700 (PDT)
Subject: python make dies :libtk8.5.so: cannot open shared object file: No 
	such file or directory
Message-ID: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>

Trying to build python-2.6.2



./configure --prefix=/usr/local --exec-prefix=/usr/local LDFLAGS="-L/
usr/local"

(runs through happily, had to make some libs local)



make runs most of the way until?



building '_tkinter' extension

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I. -I/tmp/
meld/Python-2.6.2/./Include -I. -IInclude -I./Include -I/usr/local/
include -I/tmp/meld/Python-2.6.2/Include -I/tmp/meld/Python-2.6.2 -c /
tmp/meld/Python-2.6.2/Modules/_tkinter.c -o build/temp.linux-i686-2.6/
tmp/meld/Python-2.6.2/Modules/_tkinter.o

gcc -pthread -fPIC -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
Wstrict-prototypes -DWITH_APPINIT=1 -I/usr/X11R6/include -I. -I/tmp/
meld/Python-2.6.2/./Include -I. -IInclude -I./Include -I/usr/local/
include -I/tmp/meld/Python-2.6.2/Include -I/tmp/meld/Python-2.6.2 -c /
tmp/meld/Python-2.6.2/Modules/tkappinit.c -o build/temp.linux-i686-2.6/
tmp/meld/Python-2.6.2/Modules/tkappinit.o

gcc -pthread -shared build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/
Modules/_tkinter.o build/temp.linux-i686-2.6/tmp/meld/Python-2.6.2/
Modules/tkappinit.o -L/usr/X11R6/lib64 -L/usr/X11R6/lib -L/usr/local/
lib -ltk8.5 -ltcl8.5 -lX11 -o build/lib.linux-i686-2.6/_tkinter.so

*** WARNING: renaming "_tkinter" since importing it failed:
libtk8.5.so: cannot open shared object file: No such file or directory



Failed to find the necessary bits to build these modules:

_sqlite3           bsddb185           sunaudiodev

To find the necessary bits, look in setup.py in detect_modules() for
the module's name.





Failed to build these modules:

_tkinter



running build_scripts

# cd /usr/local/lib

# ls -la | grep libtk8.5.so

-r-xr-xr-x   1 root root  1112606 Jul 10 13:28 libtk8.5.so

Am I missing something, it?s there?

Regards,

-Tony


From lists at cheimes.de  Mon Jul 13 10:09:47 2009
From: lists at cheimes.de (Christian Heimes)
Date: Mon, 13 Jul 2009 16:09:47 +0200
Subject: python make dies :libtk8.5.so: cannot open shared object file:
	No    such file or directory
In-Reply-To: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>
References: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>
Message-ID: <h3ff7a$cem$1@ger.gmane.org>

Tony Lay wrote:
> # cd /usr/local/lib
> 
> # ls -la | grep libtk8.5.so
> 
> -r-xr-xr-x   1 root root  1112606 Jul 10 13:28 libtk8.5.so
> 
> Am I missing something, it?s there?

Is /usr/local/lib in your library search path? It looks like it isn't.
Check /etc/ld.so.conf and /etc/ld.so.conf.d/.

Christian



From invalid at invalid  Mon Jul 13 10:16:12 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 13 Jul 2009 09:16:12 -0500
Subject: Problem with two instances of PySerial
References: <a27b2f730907090640od5e09c1g17caf0cdc5b04894@mail.gmail.com>
	<mailman.2932.1247199794.8015.python-list@python.org>
Message-ID: <CbOdnbWQ9_Yx3MbXnZ2dnUVZ_qydnZ2d@posted.visi>


> On Thu, 9 Jul 2009 08:40:18 -0500, Shine Jose <shinejose22 at gmail.com> wrote:

> I achieve this by creating a separate worker thread to poll
> the serial port for arrival of data and then updating the
> required widget in main thread of program. For polling the
> serial port, I create a separate instance of pySerial object.
> However, I am unable to read any data in the worker thread.
> Can the reason for this be 2 instances of pySerial objects
> being connected to serial port.

Yes.

> The reason I had this doubt was because Serial.Connect() in
> the worker thread did not throw any exception & isOpen()
> method returns true.

Under Unix, you are allowed to open a device or file as many
times as you want (there are some common cases where there is a
very useful thing to do).  However, for something like a serial
port, there's only one copy of each received data byte.
Depending on exactly how you structure your code, the incoming
data may be divided up amongst multiple readers, or one
particular reader may get all of it.

-- 
Grant Edwards                   grante             Yow! I joined scientology
                                  at               at a garage sale!!
                               visi.com            


From deets at nospam.web.de  Mon Jul 13 10:17:53 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 13 Jul 2009 16:17:53 +0200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <7c0toaF25751bU1@mid.uni-berlin.de>

seldan24 wrote:

> Hello,
> 
> I'm fairly new at Python so hopefully this question won't be too
> awful.  I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).
> I've figured out two different ways to do this, and am wondering which
> is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
> to understand exactly what occurs for each one.
> 
> The first example:
> 
> from ftplib import FTP
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except Exception, err:
>     print err
> 
> This works fine.  I read through the documentation, and my
> understanding is that there is a built-in exceptions module in python,
> that is automatically available in a built-in namespace.  Within that
> module is an 'Exception' class which would contain whatever exception
> is thrown.  So, I'm passing that to the except, along with err to hold
> the value and then print it out.
> 
> The second example:
> 
> from ftplib import FTP
> import sys
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except:
>     print sys.exc_info()
> 
> Here I, for the most part, get the same thing.  I'm not passing
> anything to except and just printing out the exception using a method
> defined in the sys module.
> 
> So, I'm new to Python... I've made it this far and am happy, but want
> to make sure I'm coding correctly from the start.  Which method is the
> better/cleaner/more standard way to continue?  Thanks for any help.

The latter is - unfortunately - the better. This comes from python allowing
all kinds of objects being thrown as exceptions, not only those extending
from a common ancestor like Exception.

You seem to have a sensible take on this, but anyway I'd like to mention
that using these kinds of catch-all code is rarely justified, as it imposes
the danger of not handling errors at all. So make sure the program spits
out a sensible error-message, and then dies. Unless it's a server-process
of course.

Diez


From invalid at invalid  Mon Jul 13 10:19:29 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 13 Jul 2009 09:19:29 -0500
Subject: need to write a assembly progrm
References: <a97ce0940907090352jd24110dk7d94cc42514eab43@mail.gmail.com>
	<op.uwup5bama8ncjz@gnudebst> <h393ob$d8u$2@ger.gmane.org>
	<mailman.3037.1247429652.8015.python-list@python.org>
Message-ID: <CbOdnbSQ9_bs38bXnZ2dnUVZ_qydnZ2d@posted.visi>

On 2009-07-12, Rhodri James <rhodri at wildebst.demon.co.uk> wrote:

>> The poorly punctuated paragraph sounds, to me, as if they mean
>> they want (Windows assumed) EXE files that can be dropped onto
>> remote/laptop machines without performing a full installation
>> of Python...
>>
>> But yes... "assembly programs" does, to me, also mean things
>> containing mnemonics for machine level opcodes.
>
> Given that to me, "assembly programs" does not mean .EXE files
> at all, not even a little bit, I'm prefering to refuse to
> guess :-)

Ah, but guessing what a poster meant to ask and then answering
the "guessed" question is a pretty popular sport here in c.l.p.
The discussions resulting from "guessed" questions are often
more informative than the answer to the intended question (if
the OP ever returns to clarify his intent).

-- 
Grant Edwards                   grante             Yow! Bo Derek ruined
                                  at               my life!
                               visi.com            


From tonylay at gmail.com  Mon Jul 13 10:24:08 2009
From: tonylay at gmail.com (Tony Lay)
Date: Mon, 13 Jul 2009 07:24:08 -0700 (PDT)
Subject: python make dies :libtk8.5.so: cannot open shared object file: No
	such file or directory
References: <5594af68-9b4b-45c7-a55d-75020d70173a@f16g2000vbf.googlegroups.com>
	<mailman.3052.1247494198.8015.python-list@python.org>
Message-ID: <af3033cd-be83-4952-9ddd-5eca139c6283@z28g2000vbl.googlegroups.com>

On Jul 13, 10:09?am, Christian Heimes <li... at cheimes.de> wrote:
> Tony Lay wrote:
> > # cd /usr/local/lib
>
> > # ls -la | grep libtk8.5.so
>
> > -r-xr-xr-x ? 1 root root ?1112606 Jul 10 13:28 libtk8.5.so
>
> > Am I missing something, it?s there?
>
> Is /usr/local/lib in your library search path? It looks like it isn't.
> Check /etc/ld.so.conf and /etc/ld.so.conf.d/.
>
> Christian

I added /usr/local/lib to ld.so.conf.d/python26.conf and ran ldconfig
(thanks Chrisitan)

Ran a make distclean (had to move the files and got a ?file not found?
from my previous working directory).

Everything compiled and installed like a charm.  Thanks!


From python at mrabarnett.plus.com  Mon Jul 13 10:33:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 13 Jul 2009 15:33:42 +0100
Subject: Best Way to Handle All Exceptions
In-Reply-To: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <4A5B45C6.5060404@mrabarnett.plus.com>

seldan24 wrote:
> Hello,
> 
> I'm fairly new at Python so hopefully this question won't be too
> awful.  I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).
> I've figured out two different ways to do this, and am wondering which
> is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
> to understand exactly what occurs for each one.
> 
> The first example:
> 
> from ftplib import FTP
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except Exception, err:
>     print err
> 
> This works fine.  I read through the documentation, and my
> understanding is that there is a built-in exceptions module in python,
> that is automatically available in a built-in namespace.  Within that
> module is an 'Exception' class which would contain whatever exception
> is thrown.  So, I'm passing that to the except, along with err to hold
> the value and then print it out.
> 
There isn't an "exceptions module"; exceptions are part of the language.

> The second example:
> 
> from ftplib import FTP
> import sys
> try:
>     ftp = FTP(ftp_host)
>     ftp.login(ftp_user, ftp_pass)
> except:
>     print sys.exc_info()
> 
This is called a "bare exception handler". It's virtually never the
right way to do it.

> Here I, for the most part, get the same thing.  I'm not passing
> anything to except and just printing out the exception using a method
> defined in the sys module.
> 
> So, I'm new to Python... I've made it this far and am happy, but want
> to make sure I'm coding correctly from the start.  Which method is the
> better/cleaner/more standard way to continue?  Thanks for any help.

You should use the most specific exception possible because at lot of
things could raise an exception:

 >>> foo

Traceback (most recent call last):
   File "<pyshell#0>", line 1, in <module>
     foo
NameError: name 'foo' is not defined
 >>> try:
     foo
except Exception, e:
     print "*** Caught an exception ***"
     print e

*** Caught an exception ***
name 'foo' is not defined


From bryanvick at gmail.com  Mon Jul 13 10:52:51 2009
From: bryanvick at gmail.com (Bryan)
Date: Mon, 13 Jul 2009 07:52:51 -0700 (PDT)
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<h383al$pln$1@engnntp2.cig.mot.com>
Message-ID: <cbbcd26b-134b-4d62-9018-a3e12e1e989a@q35g2000vbi.googlegroups.com>

On Jul 10, 12:03?pm, mgi... at motorola.com (Gary Duzan) wrote:
> In article <3af970b1-b454-4d56-a33f-889ecfaca... at l28g2000vba.googlegroups.com>,
>
> Bryan ?<bryanv... at gmail.com> wrote:
>
> >rsyncExec = '/usr/bin/ssh'
> >source = 'r... at 10.0.45.67:/home/bry/jquery.lookup'
> >dest = '/home/bry/tmp'
> >rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> >args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
>
> ? ?I think you want -e and the ssh command to be separate args.
> Something like:
>
> rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
> args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source, dest]
>
> or:
>
> rshArgs = [ '-e', '/usr/bin/ssh -i /home/bry/keys/brybackup.key' ]
> args = [rsyncExec, '-a', '-v', '--dry-run'] + ?rshArgs + [ source, dest]
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Gary Duzan
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Motorola H&NM

Separating the argument parts worked.  Strangely though, I don't need
to do that for arguments such as --files-from='/path/to/file'.  Also,
in this example code I had the rsync executable path pointing to the
ssh program, so no wonder I was getting the output of ssh!


From seldan24 at gmail.com  Mon Jul 13 11:03:27 2009
From: seldan24 at gmail.com (seldan24)
Date: Mon, 13 Jul 2009 08:03:27 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<mailman.3053.1247495610.8015.python-list@python.org>
Message-ID: <d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>

On Jul 13, 10:33?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> seldan24 wrote:
> > Hello,
>
> > I'm fairly new at Python so hopefully this question won't be too
> > awful. ?I am writing some code that will FTP to a host, and want to
> > catch any exception that may occur, take that and print it out
> > (eventually put it into a log file and perform some alerting action).
> > I've figured out two different ways to do this, and am wondering which
> > is the best (i.e. cleanest, 'right' way to proceed). ?I'm also trying
> > to understand exactly what occurs for each one.
>
> > The first example:
>
> > from ftplib import FTP
> > try:
> > ? ? ftp = FTP(ftp_host)
> > ? ? ftp.login(ftp_user, ftp_pass)
> > except Exception, err:
> > ? ? print err
>
> > This works fine. ?I read through the documentation, and my
> > understanding is that there is a built-in exceptions module in python,
> > that is automatically available in a built-in namespace. ?Within that
> > module is an 'Exception' class which would contain whatever exception
> > is thrown. ?So, I'm passing that to the except, along with err to hold
> > the value and then print it out.
>
> There isn't an "exceptions module"; exceptions are part of the language.
>
> > The second example:
>
> > from ftplib import FTP
> > import sys
> > try:
> > ? ? ftp = FTP(ftp_host)
> > ? ? ftp.login(ftp_user, ftp_pass)
> > except:
> > ? ? print sys.exc_info()
>
> This is called a "bare exception handler". It's virtually never the
> right way to do it.
>
> > Here I, for the most part, get the same thing. ?I'm not passing
> > anything to except and just printing out the exception using a method
> > defined in the sys module.
>
> > So, I'm new to Python... I've made it this far and am happy, but want
> > to make sure I'm coding correctly from the start. ?Which method is the
> > better/cleaner/more standard way to continue? ?Thanks for any help.
>
> You should use the most specific exception possible because at lot of
> things could raise an exception:
>
> ?>>> foo
>
> Traceback (most recent call last):
> ? ?File "<pyshell#0>", line 1, in <module>
> ? ? ?foo
> NameError: name 'foo' is not defined
> ?>>> try:
> ? ? ?foo
> except Exception, e:
> ? ? ?print "*** Caught an exception ***"
> ? ? ?print e
>
> *** Caught an exception ***
> name 'foo' is not defined- Hide quoted text -
>
> - Show quoted text -

Thank you both for your input.  I want to make sure I get started on
the right track.  For this particular script, I should have included
that I would take the exception contents, and pass those to the
logging module.  For this particular script, all exceptions are fatal
and I would want them to be.  I just wanted a way to catch them and
log them prior to program termination.  I can understand why folks
should always specify exact exceptions where possible if they plan on
doing something with them, but I just want to log and terminate (and
alarm) when any exception, irregardless of what it is, occurs; that's
why I'm using the catch-all approach.  I most likely should have put
in an exit() in my snippet; sorry about that.

I did notice that Python allows different objects to be thrown.  This
threw me off a bit because, at first, I was expecting everything to
come through as nice, easy tuples.  It turns out that ftplib throws
some class from the sockets module (my terminology may be off here).
As for terminology, sorry about the 'exceptions' misuse.  The Python
documentation refers to 'exceptions' as a module, albeit built-in, so
I used that language accordingly (link to doc:
http://docs.python.org/library/exceptions.html?highlight=exceptions#module-exceptions).

Anyway, thanks again for the help and advice, it is greatly
appreciated.


From floris.bruynooghe at gmail.com  Mon Jul 13 11:13:34 2009
From: floris.bruynooghe at gmail.com (Floris Bruynooghe)
Date: Mon, 13 Jul 2009 08:13:34 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <fb81ece8-4fea-4c55-b585-a95809e3ed32@k20g2000vbp.googlegroups.com>

On Jul 13, 2:26?pm, seldan24 <selda... at gmail.com> wrote:
> The first example:
>
> from ftplib import FTP
> try:
> ? ? ftp = FTP(ftp_host)
> ? ? ftp.login(ftp_user, ftp_pass)
> except Exception, err:
> ? ? print err

*If* you really do want to catch *all* exceptions (as mentioned
already it is usually better to catch specific exceptions) this is the
way to do it.

To know why you should look at the class hierarchy on
http://docs.python.org/library/exceptions.html.  The reason is that
you almost never want to be catching SystemExit, KeyboardInterrupt
etc. catching them will give you trouble at some point (unless you
really know what you're doing but then I would suggest you list them
explicitly instead of using the bare except statement).

While it is true that you could raise an object that is not a subclass
from Exception it is very bad practice, you should never do that.  And
I've haven't seen an external module in the wild that does that in
years and the stdlib will always play nice.


Regards
Floris


From hartley79 at gmail.com  Mon Jul 13 11:47:03 2009
From: hartley79 at gmail.com (hartley)
Date: Mon, 13 Jul 2009 08:47:03 -0700 (PDT)
Subject: Passing python list from C to python
Message-ID: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>

I'm very new at wrapping Python/C, and I have run into some problems.

I have one python module that provides me with a list (provideBuffer
in provideBuff.py):

 Py_Initialize();
	pName = PyString_FromString("provideBuff");
	pModule = PyImport_Import(pName);

	pFunc = PyObject_GetAttrString(pModule,"provideBuffer");

	pValue = PyObject_CallObject(pFunc,NULL);

pValue is now a PyList - i've even verified this with:

int a = PyList_Check(pValue);
	printf("%d\n", a);

However, I want to send this PyList to another python module, but I
don't know how to do this. Initially I though I could just do like
above, only swapping NULL with pValue, but that is not working.

pName2 = PyString_FromString("C-embedding");
pModule2 = PyImport_Import(pName2);
pFunc2 = PyObject_GetAttrString(pModule2,"buff");
pValue2 = PyObject_CallObject(pFunc2,pValue);

pValue2 is now False! So i guess i cannot pass pValue as an argument
to PyObject_CallObject when i want to pass an python list as an
argument. But how must a go about to make this work?


From degibb at gmail.com  Mon Jul 13 12:21:37 2009
From: degibb at gmail.com (David Gibb)
Date: Mon, 13 Jul 2009 12:21:37 -0400
Subject: list of all possible values
Message-ID: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>

Hi guys.

I was thinking about a problem I had: suppose I have a list of
possible values. I want to to have a list of all possible lists of
length n whose values are in that original list.

For example: if my values are ['a', 'b', 'c'], then all possible lists
of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.

I created a recursive program to do it, but I was wondering if there
was a better way of doing it (possibly with list comprehensions).

Here's my recursive version:

vals = ['a', 'b', 'c']

def foo(length):
    if length <=0:
        return []
    if length == 1:
        return [[x] for x in vals]
    else:
        return [x + [y] for x in foo(length - 1) for y in vals]

print foo(3)

Thanks,
David


From bjorn.m.meyer at gmail.com  Mon Jul 13 12:29:56 2009
From: bjorn.m.meyer at gmail.com (Bjorn Meyer)
Date: Mon, 13 Jul 2009 10:29:56 -0600
Subject: multiprocessing and dictionaries
In-Reply-To: <m2y6qt2ezr.fsf@cs.uu.nl>
References: <mailman.3031.1247418982.8015.python-list@python.org>
	<m2y6qt2ezr.fsf@cs.uu.nl>
Message-ID: <200907131029.56346.bjorn.m.meyer@gmail.com>


On Monday 13 July 2009 01:56:08 Piet van Oostrum wrote:

> >>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:
> >
> >BM> I am trying to convert a piece of code that I am using the thread
> > module with BM> to the multiprocessing module.
> >
> >BM> The way that I have it set up is a chunk of code reads a text file and
> > assigns BM> a dictionary key multiple values from the text file. I am
> > using locks to write BM> the values to the dictionary.
> >BM> The way that the values are written is as follows:
> >BM> 	mydict.setdefault(key, []).append(value)
> >
> >BM> The problem that I have run into is that using multiprocessing, the
> > key gets BM> set, but the values don't get appended.
> >BM> I've even tried the Manager().dict() option, but it doesn't seem to
> > work.
> >
> >BM> Is this not supported at this time or am I missing something?
>
> I think you should give more information. Try to make a *minimal* program
> that shows the problem and include it in your posting or supply a
> download link.
> --
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org

Here is what I have been using as a test.
This pretty much mimics what I am trying to do.
I put both threading and multiprocessing in the example which shows the output 
that I am looking for.

#!/usr/bin/env python

import threading
from multiprocessing import Manager, Process

name = ('test1','test2','test3')
data1 = ('dat1','dat2','dat3')
data2 = ('datA','datB','datC')

def thread_test(name,data1,data2, d):
  for nam in name:
    for num in range(0,3):
      d.setdefault(nam, []).append(data1[num])
      d.setdefault(nam, []).append(data2[num])
  print 'Thread test dict:',d

def multiprocess_test(name,data1,data2, mydict):
  for nam in name:
    for num in range(0,3):
      mydict.setdefault(nam, []).append(data1[num])
      mydict.setdefault(nam, []).append(data2[num])
  print 'Multiprocess test dic:',mydict

if __name__ == '__main__':
  mgr = Manager()
  md = mgr.dict()
  d = {}

  m = Process(target=multiprocess_test, args=(name,data1,data2,md))
  m.start()
  t = threading.Thread(target=thread_test, args=(name,data1,data2,d))
  t.start()
  
  m.join()
  t.join()
  
  print 'Thread test:',d
  print 'Multiprocess test:',md


Thanks
Bjorn



From python.list at tim.thechases.com  Mon Jul 13 12:33:20 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Mon, 13 Jul 2009 11:33:20 -0500
Subject: list of all possible values
In-Reply-To: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
References: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
Message-ID: <4A5B61D0.5070403@tim.thechases.com>

> For example: if my values are ['a', 'b', 'c'], then all possible lists
> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
> 
> I created a recursive program to do it, but I was wondering if there
> was a better way of doing it (possibly with list comprehensions).
> 
> Here's my recursive version:
> 
> vals = ['a', 'b', 'c']
> 
> def foo(length):
>     if length <=0:
>         return []
>     if length == 1:
>         return [[x] for x in vals]
>     else:
>         return [x + [y] for x in foo(length - 1) for y in vals]

Sounds like you want one of the combinitoric generators found in 
itertools[1] -- in this case, the itertools.product() does what 
you describe.  According to the docs, it was added in 2.6 so if 
you're running an older version, you'd have to back-port it.

-tkc

[1]
http://docs.python.org/library/itertools.html#itertools.product






From sjmachin at lexicon.net  Mon Jul 13 12:35:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 13 Jul 2009 09:35:16 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
Message-ID: <9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com>

On Jul 14, 1:47?am, hartley <hartle... at gmail.com> wrote:
> I'm very new at wrapping Python/C, and I have run into some problems.
>
> I have one python module that provides me with a list (provideBuffer
> in provideBuff.py):
>
> ?Py_Initialize();
> ? ? ? ? pName = PyString_FromString("provideBuff");
> ? ? ? ? pModule = PyImport_Import(pName);
>
> ? ? ? ? pFunc = PyObject_GetAttrString(pModule,"provideBuffer");
>
> ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> pValue is now a PyList - i've even verified this with:
>
> int a = PyList_Check(pValue);
> ? ? ? ? printf("%d\n", a);
>
> However, I want to send this PyList to another python module,

Please explain "send" ... do you mean the C equivalent of the Python
statement C_embedding.buff = the_pylist ?

BTW C-embedding would trigger a syntax error in Python source; best to
avoid ...

> but I
> don't know how to do this. Initially I though I could just do like
> above, only swapping NULL with pValue, but that is not working.
>
> pName2 = PyString_FromString("C-embedding");
> pModule2 = PyImport_Import(pName2);
> pFunc2 = PyObject_GetAttrString(pModule2,"buff");

Get?? Do you want Set? Is buff a Python function? Or is it the
destination of the "sending"? Any good reason for not checking the
return value for an error? [Rhetorical question; answer == "No"]

> pValue2 = PyObject_CallObject(pFunc2,pValue);

CallObject?? You used this before because you had a function and
wanted to call it because it returned you a value .... now you want to
do one of (in Python terms)

value = amodule.anattr
value = getattr(amodule, "anattr")

or

amodule.anattr = value
setattr(amodule, "anattr", value)


> pValue2 is now False!

False?? Do you mean the C NULL?

> So i guess i cannot pass pValue as an argument
> to PyObject_CallObject when i want to pass an python list as an
> argument. But how must a go about to make this work?

It's mainly just a matter of (1) knowing what you want to do (2)
picking the API that does what you want (3) checking the returned
value for error after every call.

HTH,
John



From bearophileHUGS at lycos.com  Mon Jul 13 12:35:49 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Mon, 13 Jul 2009 09:35:49 -0700 (PDT)
Subject: list of all possible values
References: <mailman.3054.1247502101.8015.python-list@python.org>
Message-ID: <907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>

David Gibb:
> For example: if my values are ['a', 'b', 'c'], then all possible lists
> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.

>>> from itertools import product
>>> list(product("abc", repeat=2))
[('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
'c'), ('c', 'a'), ('c', 'b'), ('c', 'c')]

Bye,
bearophile


From whatnextur at gmail.com  Mon Jul 13 12:50:57 2009
From: whatnextur at gmail.com (whatnext@gmail.com)
Date: Mon, 13 Jul 2009 09:50:57 -0700 (PDT)
Subject: Germany Ups Terrorism Alert Before Election
Message-ID: <cb9150e7-c396-48b6-985f-b0272ca11add@m7g2000prd.googlegroups.com>

With Germany going to the polls in a general election in three months,
authorities are on high alert after detecting an increase in online
warnings of terrorist attacks targeting the country.
The German government held high-level talks with top security and
intelligence chiefs in Berlin on Thursday to discuss the growing
threat posed by Islamic extremists and to coordinate counterterrorism
measures. Intelligence officials are alarmed by the rising number of
videos posted online by militant Islamists who say they are
specifically targeting Germany. Up to 13 videos are reported to have
appeared on the Web since January, many of them referring to the
deployment of German troops in Afghanistan.
(See pictures of U.S. Marines opening a new offensive in Afghanistan.)
for more http://www.terrorismsearch.blogspot.com/


From andreas.tawn at ubisoft.com  Mon Jul 13 12:51:07 2009
From: andreas.tawn at ubisoft.com (Andreas Tawn)
Date: Mon, 13 Jul 2009 18:51:07 +0200
Subject: list of all possible values
In-Reply-To: <907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
References: <mailman.3054.1247502101.8015.python-list@python.org>
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
Message-ID: <8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>

> David Gibb:
> > For example: if my values are ['a', 'b', 'c'], then all possible
lists
> > of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
> 
> >>> from itertools import product
> >>> list(product("abc", repeat=2))
> [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
> 'c'), ('c', 'a'), ('c', 'b'), ('c', 'c')]
> 
> Bye,
> bearophile

Certainly possible with list comprehensions.

>>> a = "abc"
>>> [(x, y) for x in a for y in a]
[('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b', 'c'),
('c', 'a'), ('c', 'b'), ('c', 'c')]

But I like bearophile's version better.

Cheers,

Drea


From gabriel.rossetti at arimaz.com  Mon Jul 13 13:08:12 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Mon, 13 Jul 2009 19:08:12 +0200
Subject: Blocking XMPP API?
In-Reply-To: <h3f6ru$dld$11@lust.ihug.co.nz>
References: <mailman.2893.1247147391.8015.python-list@python.org>
	<h3f6ru$dld$11@lust.ihug.co.nz>
Message-ID: <4A5B69FC.5010109@arimaz.com>

Lawrence D'Oliveiro wrote:
> In message <mailman.2893.1247147391.8015.python-list at python.org>, Gabriel 
> Rossetti wrote:
>
>   
>> I am looking for blocking XMPP API. I'm wanting to make a webservice
>> that uses XMPP, but all the XMPP libs I find are non-blocking (i.e. w/
>> callbacks).
>>     
>
> So why not have the caller sleep or something until the callback is invoked?
>
> It's easier to turn an async API into a synchronous one than the other way 
> round.
>
>   
Yes, that is what I ended up doing, thanks for the response though :-)

Gabriel


From skong1 at gmail.com  Mon Jul 13 13:10:00 2009
From: skong1 at gmail.com (sityee kong)
Date: Mon, 13 Jul 2009 10:10:00 -0700
Subject: Memory error due to big input file
Message-ID: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>

Hi All,

I have a similar problem that many new python users might encounter. I would
really appreciate if you could help me fix the error.
I have a big text file with size more than 2GB. It turned out memory error
when reading in this file. Here is my python script, the error occurred at
line -- self.fh.readlines().

import math
import time

class textfile:
  def __init__(self,fname):
     self.name=fname
     self.fh=open(fname)
     self.fh.readline()
     self.lines=self.fh.readlines()

a=textfile("/home/sservice/nfbc/GenoData/CompareCalls3.diff")

lfile=len(a.lines)

def myfun(snp,start,end):
  subdata=a.lines[start:end+1]
  NEWmiss=0
  OLDmiss=0
  DIFF=0
  for row in subdata:
     k=row.split()
     if (k[3]=="0/0") & (k[4]!="0/0"):
        NEWmiss=NEWmiss+1
     elif (k[3]!="0/0") & (k[4]=="0/0"):
        OLDmiss=OLDmiss+1
     elif (k[3]!="0/0") & (k[4]!="0/0"):
        DIFF=DIFF+1
  result.write(snp+" "+str(NEWmiss)+" "+str(OLDmiss)+" "+str(DIFF)+"\n")

result=open("Summary_noLoop_diff3.txt","w")
result.write("SNP NEWmiss OLDmiss DIFF\n")

start=0
snp=0
for i in range(lfile):
  if (i==0): continue
  after=a.lines[i].split()
  before=a.lines[i-1].split()
  if (before[0]==after[0]):
    if (i!=(lfile-1)): continue
    else:
      end=lfile-1
      myfun(before[0],start,end)
      snp=snp+1
  else:
    end=i-1
    myfun(before[0],start,end)
    snp=snp+1
    start=i
    if (i ==(lfile-1)):
      myfun(after[0],start,start)
      snp=snp+1

result.close()

  sincerely, phoebe
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/79fc0e80/attachment-0001.html>

From skip at pobox.com  Mon Jul 13 13:18:25 2009
From: skip at pobox.com (skip at pobox.com)
Date: Mon, 13 Jul 2009 12:18:25 -0500
Subject: Memory error due to big input file
In-Reply-To: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
Message-ID: <19035.27745.515643.604146@montanaro.dyndns.org>


    phoebe> I have a big text file with size more than 2GB. It turned out
    phoebe> memory error when reading in this file. Here is my python
    phoebe> script, the error occurred at line -- self.fh.readlines().

    phoebe> import math
    phoebe> import time

    phoebe> class textfile:
    phoebe>   def __init__(self,fname):
    phoebe>      self.name=fname
    phoebe>      self.fh=open(fname)
    phoebe>      self.fh.readline()
    phoebe>      self.lines=self.fh.readlines()

Don't do that.  The problem is that you are trying to read the entire file
into memory.  Learn to operate a line (or a few lines) at a time.  Try
something like:

    a = open("/home/sservice/nfbc/GenoData/CompareCalls3.diff")
    for line in a:
        do your per-line work here

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    when i wake up with a heart rate below 40, i head right for the espresso
    machine. -- chaos @ forums.usms.org


From python at mrabarnett.plus.com  Mon Jul 13 13:20:43 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 13 Jul 2009 18:20:43 +0100
Subject: Memory error due to big input file
In-Reply-To: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
Message-ID: <4A5B6CEB.1010507@mrabarnett.plus.com>

sityee kong wrote:
> Hi All,
> 
> I have a similar problem that many new python users might encounter. I 
> would really appreciate if you could help me fix the error.
> I have a big text file with size more than 2GB. It turned out memory 
> error when reading in this file. Here is my python script, the error 
> occurred at line -- self.fh.readlines().
> 
[snip code]
Your 'error' is that you're running it on a computer with insufficient
memory.



From gabriel.rossetti at arimaz.com  Mon Jul 13 13:28:27 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Mon, 13 Jul 2009 19:28:27 +0200
Subject: Threading.Condition problem
In-Reply-To: <m21vom6hla.fsf@cs.uu.nl>
References: <mailman.2957.1247240742.8015.python-list@python.org>
	<m21vom6hla.fsf@cs.uu.nl>
Message-ID: <4A5B6EBB.30906@arimaz.com>


Piet van Oostrum wrote:
>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>             
>
>   
>> GR> Sorry if this appears twice, I sent it once with an attachment and it never
>> GR> arrived so maybe the attachment is posing problems. I inlined the code this
>> GR> time (at the bottom), thank you,
>>     
>
>   
>> GR> Gabriel
>>     
>
>   
>> GR> ########################## Original message ############################
>>     
>
>   
>> GR> Hello everyone,
>>     
>
>   
>> GR> I wrote a small example that listens for xmpp msgs in a thread. The main
>> GR> program calls a function that blocks (using Condition.wait) until a msg
>> GR> has been received and then returns the msg. When a msg arrives, it is
>> GR> put in a variable in the thread's object, it then calls the notify()
>> GR> attr on the Condition object. For some reason, this doesn't work, the
>> GR> thread gets the msg, tries to notify the Condition object, fails because
>> GR> the lock has not been acquired yet and blocks. I tried ignoring the
>> GR> failure, thinking that since it has not been acquired yet then when it
>> GR> is, it will get the msg right away and never call Condition.wait, thus
>> GR> not causing any problems, but this does not work either. Does someone
>> GR> know what I am doing wrong? I attached the code to this msg.
>>     
>
> The code that puts the message in the variable should also acquire the
> lock:
>
>
>      def onMessage(self, conn, msg):
>          with self._cv:
>              self.message = msg
>              self._cv.notify()
>   

Thank you, that was the problem, I eventually found that
> A couple of remarks:
>
> 1. I think the code is neater if all manipulation with the condition is
>    done in the same class (actually in the same instance -- making this
>    instance into a monitor).
>   

The reason I didn't do that is that I don' t want the Listener to sleep, 
I maybe over simplified the example, I actually put them in a dictionary 
as they come in, so in your example, if I have several threads waiting 
on msgs it wouldn't work. I'm trying to make a webservice api thay will 
also be turned into a java .jar for people that need java. Now that I 
think about it, each session will have an instance of the object so msgs 
shouldn' t get mixed up (one connection per user), so I could block in 
the thread. I'll try your suggestion as I think it is cleaner.

> class Listener(Thread):
>     def __init__(self, ws):
>         Thread.__init__(self)
>         self.interrupt = Event()
>         self.message = None
>         self._cv = Condition()
>         self.client = ws._client
>         self.client.RegisterHandler('message', self.onMessage)
>     
>     def onMessage(self, conn, msg):
>         with self._cv:
>             self.message = msg
>             try:
>                 self._cv.notify()
>             except RuntimeError:
>                 print "self._cv has not acquired the lock yet"
>     
>     def getMsg(self):
>         with self._cv:
>             while !self.message
>                 self._cv.wait()
>             return self.message
>
> class WS(object):
>     def __init__(self, username, password, res):
>         self._jid = xmpp.protocol.JID(username)
>         self._client = xmpp.Client(self._jid.getDomain())
> #        self._cv = Condition()
>     
>     def getMsg(self, mid=None):
>         """
>         """
>         return self._listener.getMsg()
>
> Of course I haven't tested this code as I don't have the context
> modules.
>
> 2. I don't know if more than one message can be delivered in the same
>    instance. If yes, than your code will not work, and neither will the
>    code above as, the message instance variable is never cleared. So the
>    next getMsg will be happy to deliver the previous one.
>    You would have to clear it when returning this one.
>     
>   
Like I said above, in reality I have a dict not just a simple variable.
>     def getMsg(self):
>         with self._cv:
>             while !self.message
>                 self._cv.wait()
>             msg = self.message
>             self.message = None
>             return msg
>
> 3. If the messages come in faster than they can be processed some will
>    be lost as they will overwrite the previous one in the self.message
>    variable. The solution is to use a threading.Queue to transfer the
>    messages from one thread to the other. This also saves you the hassle
>    of doing your own synchronisation like above. If you are not familiar
>    with synchronising multithreaded applications it is very easy to make
>    errors and even if you are it is quite easy to do them wrong. I have
>    been involved in distributed programming courses at university level
>    and I have seen many errors in this area.
>   
I used a dict because the API can also be setup to be async and use 
callbacks, so I had to be able to
access the msgs directly and quickly.

Gabriel


From vilya.harvey at gmail.com  Mon Jul 13 13:55:50 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Mon, 13 Jul 2009 18:55:50 +0100
Subject: Best Way to Handle All Exceptions
In-Reply-To: <d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<mailman.3053.1247495610.8015.python-list@python.org>
	<d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>
Message-ID: <6aef848f0907131055p76072a24h68ef2636b9676f50@mail.gmail.com>

2009/7/13 seldan24 <seldan24 at gmail.com>:
> Thank you both for your input. ?I want to make sure I get started on
> the right track. ?For this particular script, I should have included
> that I would take the exception contents, and pass those to the
> logging module. ?For this particular script, all exceptions are fatal
> and I would want them to be. ?I just wanted a way to catch them and
> log them prior to program termination.

The logging module has a function specifically to handle this case:

try:
    # do something
except:
    logging.exception("Uh oh...")

The exception() method will automatically add details of the exception
to the log message it creates; as per the docs, you should only call
it from within an exception handler.

Hope that helps,

Vil.


From emile at fenx.com  Mon Jul 13 13:58:25 2009
From: emile at fenx.com (Emile van Sebille)
Date: Mon, 13 Jul 2009 10:58:25 -0700
Subject: list of all possible values
In-Reply-To: <4A5B61D0.5070403@tim.thechases.com>
References: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
	<4A5B61D0.5070403@tim.thechases.com>
Message-ID: <h3fsjq$p8l$1@ger.gmane.org>

On 7/13/2009 9:33 AM Tim Chase said...
>> For example: if my values are ['a', 'b', 'c'], then all possible lists
>> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
>>
>> I created a recursive program to do it, but I was wondering if there
>> was a better way of doing it (possibly with list comprehensions).
>>
>> Here's my recursive version:
>>
>> vals = ['a', 'b', 'c']
>>
>> def foo(length):
>>     if length <=0:
>>         return []
>>     if length == 1:
>>         return [[x] for x in vals]
>>     else:
>>         return [x + [y] for x in foo(length - 1) for y in vals]
> 
> Sounds like you want one of the combinitoric generators found in 
> itertools[1] -- in this case, the itertools.product() does what you 
> describe.  According to the docs, it was added in 2.6 so if you're 
> running an older version, you'd have to back-port it

Or on systems with list comps try:

 >>> V='abc'
 >>> ['%s%s'%(ii,jj) for ii in V for jj in V]
['aa', 'ab', 'ac', 'ba', 'bb', 'bc', 'ca', 'cb', 'cc']
 >>>

Emile



From mantihor at gmail.com  Mon Jul 13 14:08:39 2009
From: mantihor at gmail.com (Bogdan Opanchuk)
Date: Mon, 13 Jul 2009 11:08:39 -0700 (PDT)
Subject: How to override Marshaller/Unmarshaller in xmlrpc?
Message-ID: <d2a08ca3-f4ce-4df0-a6d6-32aac1bb1d83@l2g2000vba.googlegroups.com>

Is there a way to override marshaller in xmlrpc.client properly? For
example, I want to hide bytes -> Binary transformation inside
marshaller (i.e., just let user pass a bytes value to function and
marshaller dumps it in base64 autmatically). Unfortunately, I cannot
just make a derived class with necessary dump_* function and pass it
to client and server; marshaller initialization seems to be hidden
inside xmlrpc.

So, here's the question - is there a nice way to do it (because there
are some dirty ways like rewriting getparser() ans so on, but I don't
like the idea of copypasting code from library)? Or should I
reconsider my design instead?

Thanks in advance.


From degibb at gmail.com  Mon Jul 13 14:15:24 2009
From: degibb at gmail.com (David Gibb)
Date: Mon, 13 Jul 2009 14:15:24 -0400
Subject: list of all possible values
In-Reply-To: <h3fsjq$p8l$1@ger.gmane.org>
References: <ef49cad40907130921s23084e33mfa0be34c02e28c74@mail.gmail.com>
	<4A5B61D0.5070403@tim.thechases.com> <h3fsjq$p8l$1@ger.gmane.org>
Message-ID: <ef49cad40907131115g4f844d36o6723fa6e46b1d95d@mail.gmail.com>

> Or on systems with list comps try:
>
>>>> V='abc'
>>>> ['%s%s'%(ii,jj) for ii in V for jj in V]
> ['aa', 'ab', 'ac', 'ba', 'bb', 'bc', 'ca', 'cb', 'cc']
>>>>

Yeah, except that the length here is hard-coded. There's no way (as
far as I can tell, at least), to make this generic with respect to
list length.

Thanks for the itertools suggestion, guys. I was hoping to improve my
list-comprehension-fu, but that module was the next best thing.

David

On Mon, Jul 13, 2009 at 1:58 PM, Emile van Sebille<emile at fenx.com> wrote:
> On 7/13/2009 9:33 AM Tim Chase said...
>>>
>>> For example: if my values are ['a', 'b', 'c'], then all possible lists
>>> of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.
>>>
>>> I created a recursive program to do it, but I was wondering if there
>>> was a better way of doing it (possibly with list comprehensions).
>>>
>>> Here's my recursive version:
>>>
>>> vals = ['a', 'b', 'c']
>>>
>>> def foo(length):
>>> ? ?if length <=0:
>>> ? ? ? ?return []
>>> ? ?if length == 1:
>>> ? ? ? ?return [[x] for x in vals]
>>> ? ?else:
>>> ? ? ? ?return [x + [y] for x in foo(length - 1) for y in vals]
>>
>> Sounds like you want one of the combinitoric generators found in
>> itertools[1] -- in this case, the itertools.product() does what you
>> describe. ?According to the docs, it was added in 2.6 so if you're running
>> an older version, you'd have to back-port it
>

>
> Emile
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From darkwater42 at gmail.com  Mon Jul 13 14:19:59 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Mon, 13 Jul 2009 11:19:59 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
Message-ID: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>

I couldn't find a good algorithms forum on the Internet, so I guess
I'll ask this question here instead: Is it possible to efficiently
maintain a binary search tree in a flat array (i.e., without using
pointers), as is typically done for a binary heap?

It *is* possible, of course, to keep an ordered list in a flat array,
and then do a binary search on the ordered array, but then insertion
and deletion are O(n), rather than O(log n). It would also clearly be
possible to store a balanced binary tree in a flat array, storing the
children of the node at index i at indices 2*i and 2*i + 1, just as
one does for a binary heap. But if you do that, I don't know if you
could then do insertions and deletions in O(log n) time.

One idea that came to mind, is that maybe it is possible using a
"treap", which is a combination of a binary heap and a binary search
tree. Insertions and deletions in binary heaps can be done in O(log n)
in a flat array, but I don't know if this is also true for a treap,
since you also have the binary search tree invariants to maintain, in
addition to the binary heap invariants. For all I know, this might
cause rotations to no longer be O(log n).

|>ouglas


From piet at cs.uu.nl  Mon Jul 13 14:25:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 20:25:58 +0200
Subject: Automate rsync w/ authentication
References: <3af970b1-b454-4d56-a33f-889ecfacacc5@l28g2000vba.googlegroups.com>
	<h383al$pln$1@engnntp2.cig.mot.com>
	<cbbcd26b-134b-4d62-9018-a3e12e1e989a@q35g2000vbi.googlegroups.com>
Message-ID: <m2ocro1lu1.fsf@cs.uu.nl>

>>>>> Bryan <bryanvick at gmail.com> (B) wrote:

>B> On Jul 10, 12:03?pm, mgi... at motorola.com (Gary Duzan) wrote:
>>> In article <3af970b1-b454-4d56-a33f-889ecfaca... at l28g2000vba.googlegroups.com>,
>>> 
>>> Bryan ?<bryanv... at gmail.com> wrote:
>>> 
>>> >rsyncExec = '/usr/bin/ssh'
>>> >source = 'r... at 10.0.45.67:/home/bry/jquery.lookup'
>>> >dest = '/home/bry/tmp'
>>> >rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
>>> >args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]
>>> 
>>> ? ?I think you want -e and the ssh command to be separate args.
>>> Something like:
>>> 
>>> rshArg = '/usr/bin/ssh -i /home/bry/keys/brybackup.key'
>>> args = [rsyncExec, '-a', '-v', '--dry-run', '-e', rshArg, source, dest]
>>> 
>>> or:
>>> 
>>> rshArgs = [ '-e', '/usr/bin/ssh -i /home/bry/keys/brybackup.key' ]
>>> args = [rsyncExec, '-a', '-v', '--dry-run'] + ?rshArgs + [ source, dest]
>>> 
>>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Gary Duzan
>>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Motorola H&NM

>B> Separating the argument parts worked.  Strangely though, I don't need
>B> to do that for arguments such as --files-from='/path/to/file'.  Also,
>B> in this example code I had the rsync executable path pointing to the
>B> ssh program, so no wonder I was getting the output of ssh!

I should have seen that because I changed it in my own copy!!!

--files-from='/path/to/file *is* one argument, in contrast to 
-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key" which is two
arguments.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 14:33:17 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 20:33:17 +0200
Subject: Threading.Condition problem
References: <mailman.2957.1247240742.8015.python-list@python.org>
	<m21vom6hla.fsf@cs.uu.nl>
	<mailman.3061.1247506110.8015.python-list@python.org>
Message-ID: <m2k52c1lhu.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Piet van Oostrum wrote:
...
>GR> I wrote a small example that listens for xmpp msgs in a thread. The main
>GR> program calls a function that blocks (using Condition.wait) until a msg
>GR> has been received and then returns the msg. When a msg arrives, it is
>GR> put in a variable in the thread's object, it then calls the notify()
>GR> attr on the Condition object. For some reason, this doesn't work, the
>GR> thread gets the msg, tries to notify the Condition object, fails because
>GR> the lock has not been acquired yet and blocks. I tried ignoring the
>GR> failure, thinking that since it has not been acquired yet then when it
>GR> is, it will get the msg right away and never call Condition.wait, thus
>GR> not causing any problems, but this does not work either. Does someone
>GR> know what I am doing wrong? I attached the code to this msg.
>>>> 
>>> 
>>> The code that puts the message in the variable should also acquire the
>>> lock:
>>> 
>>> 
>>> def onMessage(self, conn, msg):
>>> with self._cv:
>>> self.message = msg
>>> self._cv.notify()
>>> 

>GR> Thank you, that was the problem, I eventually found that
>>> A couple of remarks:
>>> 
>>> 1. I think the code is neater if all manipulation with the condition is
>>> done in the same class (actually in the same instance -- making this
>>> instance into a monitor).
>>> 

>GR> The reason I didn't do that is that I don' t want the Listener to sleep, I
>GR> maybe over simplified the example, I actually put them in a dictionary as
>GR> they come in, so in your example, if I have several threads waiting on msgs
>GR> it wouldn't work. I'm trying to make a webservice api thay will also be
>GR> turned into a java .jar for people that need java. Now that I think about
>GR> it, each session will have an instance of the object so msgs shouldn' t get
>GR> mixed up (one connection per user), so I could block in the thread. I'll
>GR> try your suggestion as I think it is cleaner.

Sleeping as you call it is better than busy waiting. You must have some
synchronisation to make it efficient.
If you put the messages in a dictionary access to the dictionary must be
protected. Having several threads waiting for the messages doesn't
prevent you from using proper synchronisation. Maybe you must use
notify_all instead of notify.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From http  Mon Jul 13 14:55:34 2009
From: http (Paul Rubin)
Date: 13 Jul 2009 11:55:34 -0700
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
Message-ID: <7x7hycmmzd.fsf@ruckus.brouhaha.com>

Douglas Alan <darkwater42 at gmail.com> writes:
> It would also clearly be
> possible to store a balanced binary tree in a flat array, storing the
> children of the node at index i at indices 2*i and 2*i + 1, just as
> one does for a binary heap. But if you do that, I don't know if you
> could then do insertions and deletions in O(log n) time.

Probably not.  Maybe you could organize a 2-3 tree like that, at the
expense of some space.


From piet at cs.uu.nl  Mon Jul 13 15:12:18 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 21:12:18 +0200
Subject: multiprocessing and dictionaries
References: <mailman.3031.1247418982.8015.python-list@python.org>
	<m2y6qt2ezr.fsf@cs.uu.nl>
	<mailman.3056.1247503227.8015.python-list@python.org>
Message-ID: <m2ab381jot.fsf@cs.uu.nl>

>>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:

>BM> Here is what I have been using as a test.
>BM> This pretty much mimics what I am trying to do.
>BM> I put both threading and multiprocessing in the example which shows
>BM> the output that I am looking for.

>BM> #!/usr/bin/env python

>BM> import threading
>BM> from multiprocessing import Manager, Process

>BM> name = ('test1','test2','test3')
>BM> data1 = ('dat1','dat2','dat3')
>BM> data2 = ('datA','datB','datC')

[snip]

>BM> def multiprocess_test(name,data1,data2, mydict):
>BM>   for nam in name:
>BM>     for num in range(0,3):
>BM>       mydict.setdefault(nam, []).append(data1[num])
>BM>       mydict.setdefault(nam, []).append(data2[num])
>BM>   print 'Multiprocess test dic:',mydict

I guess what's happening is this:

d.setdefault(nam, []) returns a list, initially an empty list ([]). This
list gets appended to. However, this list is a local list in the
multi-process_test Process, therefore the result is not reflected in the
original list inside the manager. Therefore all your updates get lost.
You will have to do operations directly on the dictionary itself, not on
any intermediary objects. Of course with the threading the situation is
different as all operations are local.

This works:

def multiprocess_test(name,data1,data2, mydict):
  print name, data1, data2
  for nam in name:
    for num in range(0,3):
      mydict.setdefault(nam, [])
      mydict[nam] += [data1[num]]
      mydict[nam] += [data2[num]]
  print 'Multiprocess test dic:',mydict

If you have more than one process operating on the dictionary
simultaneously you have to beware of race conditions!!
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 13 15:31:28 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 13 Jul 2009 21:31:28 +0200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <m263dw1isv.fsf@cs.uu.nl>

>>>>> seldan24 <seldan24 at gmail.com> (s) wrote:

>s> Hello,
>s> I'm fairly new at Python so hopefully this question won't be too
>s> awful.  I am writing some code that will FTP to a host, and want to
>s> catch any exception that may occur, take that and print it out
>s> (eventually put it into a log file and perform some alerting action).
>s> I've figured out two different ways to do this, and am wondering which
>s> is the best (i.e. cleanest, 'right' way to proceed).  I'm also trying
>s> to understand exactly what occurs for each one.

>s> The first example:

>s> from ftplib import FTP
>s> try:
>s>     ftp = FTP(ftp_host)
>s>     ftp.login(ftp_user, ftp_pass)
>s> except Exception, err:
>s>     print err

I think you should restrict yourself to those exceptions that are
related to ftp. Do you want to catch an exception like a misspelling in
one of the variables?

from ftplib import FTP, all_errors

try:
    ftp = FTP(ftp_host)
    ftp.login(ftp_user, ftp_pass)
except all_errors, err:
    print err

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Mon Jul 13 15:57:38 2009
From: aahz at pythoncraft.com (Aahz)
Date: 13 Jul 2009 12:57:38 -0700
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
Message-ID: <h3g3ji$p90$1@panix3.panix.com>

In article <ae6c3191-1167-43eb-9d36-23c7c49b5876 at l28g2000vba.googlegroups.com>,
Douglas Alan  <darkwater42 at gmail.com> wrote:
>
>I couldn't find a good algorithms forum on the Internet, so I guess
>I'll ask this question here instead: Is it possible to efficiently
>maintain a binary search tree in a flat array (i.e., without using
>pointers), as is typically done for a binary heap?
>
>It *is* possible, of course, to keep an ordered list in a flat array,
>and then do a binary search on the ordered array, but then insertion
>and deletion are O(n), rather than O(log n). 

Still, unless your list is large (more than thousands of elements),
that's the way you should go.  See the bisect module.  Thing is, the
speed difference between C and Python means the constant for insertion
and deletion is very very small relative to bytecode speed.  Keep in
mind that Python's object/binding model means that you're shuffling
pointers in the list rather than items.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From newport at freemail.hu  Mon Jul 13 16:17:31 2009
From: newport at freemail.hu (Andras Szabo)
Date: Mon, 13 Jul 2009 23:17:31 +0300
Subject: Tkinter / Entry widget problem
Message-ID: <E68CFAD0-A09B-4B2B-9E38-2EFD758BE685@freemail.hu>

Hello. I searched the archives but couldn't find a solution to a  
problem related to the Entry widget in Tkinter.

When creating a pop-up window in an app, which contains an Entry  
widget, I want this widget to contain some default string, to have all  
this default string selected (as if the user had manually selected  
everything), and to have the focus transferred to this widget.

(The idea is then that if the window pops up, the user won't have to  
click or press Tab any more before being able to type what is needed  
in the textbox, overwriting what is written there already.)

I thought this might be the way to go:

entrybox=Entry(toplevel_parent_window)
entrybox.insert(0,"Some default string")
entrybox.select_range(0,END)
entrybox.focus_set()
entrybox.pack()

But it doesn't seem to work - the focus is not transferred to the  
Entry widget, and the text does not appear to be selected (even though  
after this entrybox.selection_present() returns True).

What am I doing wrong?

andras


From tjreedy at udel.edu  Mon Jul 13 16:19:14 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 13 Jul 2009 16:19:14 -0400
Subject: Best Way to Handle All Exceptions
In-Reply-To: <7c0toaF25751bU1@mid.uni-berlin.de>
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<7c0toaF25751bU1@mid.uni-berlin.de>
Message-ID: <h3g4rv$k0s$1@ger.gmane.org>

Diez B. Roggisch wrote:

> The latter is - unfortunately - the better. This comes from python allowing
> all kinds of objects being thrown as exceptions, not only those extending
> from a common ancestor like Exception.

Fixed in Python 3. exceptions, without exceptions, are instances of 
BaseException, either directly or as instances of subcleasses of 
BaseException.

One of many reasons to switch when possible.
tjr



From darkwater42 at gmail.com  Mon Jul 13 16:47:19 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Mon, 13 Jul 2009 13:47:19 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
Message-ID: <5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>

On Jul 13, 3:57?pm, a... at pythoncraft.com (Aahz) wrote:

> Still, unless your list is large (more than thousands of elements),
> that's the way you should go. ?See the bisect module. ?Thing is, the
> speed difference between C and Python means the constant for insertion
> and deletion is very very small relative to bytecode speed. ?Keep in
> mind that Python's object/binding model means that you're shuffling
> pointers in the list rather than items.

Thank you. My question wasn't intended to be Python specific, though.
I am just curious for purely academic reasons about whether there is
such an algorithm. All the sources I've skimmed only seem to the
answer the question via omission. Which is kind of strange, since it
seems to me like an obvious question to ask.

If I find the free time, I might try to work out myself whether it can
be done with a treap.

|>ouglas


From davea at ieee.org  Mon Jul 13 17:01:17 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 13 Jul 2009 17:01:17 -0400
Subject: Memory error due to big input file
In-Reply-To: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
Message-ID: <4A5BA09D.9070402@ieee.org>

sityee kong wrote:
> Hi All,
>
> I have a similar problem that many new python users might encounter. I would
> really appreciate if you could help me fix the error.
> I have a big text file with size more than 2GB. It turned out memory error
> when reading in this file. Here is my python script, the error occurred at
> line -- self.fh.readlines().
>
> import math
> import time
>
> class textfile:
>   def __init__(self,fname):
>      self.name=fname
>      self.fh=open(fname)
>      self.fh.readline()
>      self.lines=self.fh.readlines()
>
> a=textfile("/home/sservice/nfbc/GenoData/CompareCalls3.diff")
>
> lfile=len(a.lines)
>
> def myfun(snp,start,end):
>   subdata=a.lines[start:end+1]
>   NEWmiss=0
>   OLDmiss=0
>   DIFF=0
>   for row in subdata:
>      k=row.split()
>      if (k[3]=="0/0") & (k[4]!="0/0"):
>         NEWmiss=NEWmiss+1
>      elif (k[3]!="0/0") & (k[4]=="0/0"):
>         OLDmiss=OLDmiss+1
>      elif (k[3]!="0/0") & (k[4]!="0/0"):
>         DIFF=DIFF+1
>   result.write(snp+" "+str(NEWmiss)+" "+str(OLDmiss)+" "+str(DIFF)+"\n")
>
> result=open("Summary_noLoop_diff3.txt","w")
> result.write("SNP NEWmiss OLDmiss DIFF\n")
>
> start=0
> snp=0
> for i in range(lfile):
>   if (i==0): continue
>   after=a.lines[i].split()
>   before=a.lines[i-1].split()
>   if (before[0]==after[0]):
>     if (i!=(lfile-1)): continue
>     else:
>       end=lfile-1
>       myfun(before[0],start,end)
>       snp=snp+1
>   else:
>     end=i-1
>     myfun(before[0],start,end)
>     snp=snp+1
>     start=i
>     if (i ==(lfile-1)):
>       myfun(after[0],start,start)
>       snp=snp+1
>
> result.close()
>
>   sincerely, phoebe
>
>   
Others have pointed out that you have too little memory for a 2gig data 
structure.  If you're running on a 32bit system, chances are it won't 
matter how much memory you add, a process is limited to 4gb, and the OS 
typically takes about half of it, your code and other data takes some, 
and you don't have 2gig left.   A 64 bit version of Python, running on a 
64bit OS, might be able to "just work."

Anyway, loading the whole file into a list is seldom the best answer, 
except for files under a meg or so.  It's usually better to process the 
file in sequence.  It looks like you're also making slices of that data, 
so they could potentially be pretty big as well.

If you can be assured that you only need the current line and the 
previous two (for example), then you can use a list of just those three, 
and delete the oldest one, and add a new one to that list each time 
through the loop.

Or, you can add some methods to that 'textfile' class that fetch a line 
by index.  Brute force, you could pre-scan the file, and record all the 
file offsets for the lines you find, rather than storing the actual 
line.  So you still have just as big a list, but it's a list of 
integers.  Then when somebody calls your method, he passes an integer, 
and you return the particular line.  A little caching for performance, 
and you're good to go.

Anyway, if you organize it that way, you can code the rest of the module 
to not care whether the whole file is really in memory or not.

BTW, you should derive all your classes from something.  If nothing 
else, use object.
  class textfile(object):




From aaron.hildebrandt at gmail.com  Mon Jul 13 17:14:27 2009
From: aaron.hildebrandt at gmail.com (Aaron Scott)
Date: Mon, 13 Jul 2009 14:14:27 -0700 (PDT)
Subject: Pickling classes -- disappearing lists?
Message-ID: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>

I'm trying to pickle an instance of a class. It mostly works just fine
-- I can save the pickle to a file, restore it from that file, and
it's mostly okay. The problem is, some lists seem to disappear. For
example (snipped and crunched from the code giving me trouble):

---


class InitGame:
	value = False
	journal = []


game.InitGame()


def Save():
	global game
	import cPickle, gzip, os

	# Change some data
	game.journal.append("A value")
	game.value = True

	pickles = {'game': game}
	jar = gzip.open("pickefile", 'wb')
	cPickle.dump(pickles, jar, 2)
	jar.close()


def Load():
	global game
	import gzip, os, cPickle
	jar = gzip.open("picklefile", 'r')
	loaded = cPickle.load(jar)
	jar.close()
	game = loaded["game"]


---

Now, if I save a pickle, then load it back in, I'll get an instance of
InitGame called "game", and game.value will be true, but the list
"journal" will be empty.

Am I missing something obvious about the pickle spec? Am I doing
something wrong? Or should I be hunting for a deeper bug in the code?
I've noticed that pretty much anything that's a list isn't saving to
the pickle (or loading from the pickle... it's hard to tell which).


From aaron.hildebrandt at gmail.com  Mon Jul 13 17:20:13 2009
From: aaron.hildebrandt at gmail.com (Aaron Scott)
Date: Mon, 13 Jul 2009 14:20:13 -0700 (PDT)
Subject: Memory error due to big input file
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com> 
	<mailman.3067.1247518893.8015.python-list@python.org>
Message-ID: <4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>

> BTW, you should derive all your classes from something. ?If nothing
> else, use object.
> ? class textfile(object):

Just out of curiousity... why is that? I've been coding in Python for
a long time, and I never derive my base classes. What's the advantage
to deriving them?


From l.lensgraf at gmail.com  Mon Jul 13 17:44:44 2009
From: l.lensgraf at gmail.com (DrLeif)
Date: Mon, 13 Jul 2009 14:44:44 -0700 (PDT)
Subject: PDF: finding a blank image
Message-ID: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>

I have about 6000 PDF files which have been produced using a scanner
with more being produced each day.  The PDF files contain old paper
records which have been taking up space.   The scanner is set to
detect when there is information on the backside of the page (duplex
scan).  The problem of course is it's not the always reliable and we
wind up with a number of PDF files containing blank pages.

What I would like to do is have python detect a "blank" pages in a PDF
file and remove it.  Any suggestions?


Thanks,
DrL


From clp2 at rebertia.com  Mon Jul 13 17:50:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 14:50:23 -0700
Subject: Pickling classes -- disappearing lists?
In-Reply-To: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>
References: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>
Message-ID: <50697b2c0907131450j5d3f9799l2e9c206b3c749f39@mail.gmail.com>

On Mon, Jul 13, 2009 at 2:14 PM, Aaron Scott<aaron.hildebrandt at gmail.com> wrote:
> I'm trying to pickle an instance of a class. It mostly works just fine
> -- I can save the pickle to a file, restore it from that file, and
> it's mostly okay. The problem is, some lists seem to disappear. For
> example (snipped and crunched from the code giving me trouble):
>
> ---
>
>
> class InitGame:
> ? ? ? ?value = False
> ? ? ? ?journal = []
>
>
> game.InitGame()

That line doesn't make sense with the code you've given...

> def Save():
> ? ? ? ?global game
> ? ? ? ?import cPickle, gzip, os
>
> ? ? ? ?# Change some data
> ? ? ? ?game.journal.append("A value")
> ? ? ? ?game.value = True
>
> ? ? ? ?pickles = {'game': game}
> ? ? ? ?jar = gzip.open("pickefile", 'wb')
> ? ? ? ?cPickle.dump(pickles, jar, 2)
> ? ? ? ?jar.close()
>
>
> def Load():
> ? ? ? ?global game
> ? ? ? ?import gzip, os, cPickle
> ? ? ? ?jar = gzip.open("picklefile", 'r')
> ? ? ? ?loaded = cPickle.load(jar)
> ? ? ? ?jar.close()
> ? ? ? ?game = loaded["game"]
>
>
> ---
>
> Now, if I save a pickle, then load it back in, I'll get an instance of
> InitGame called "game", and game.value will be true, but the list
> "journal" will be empty.
>
> Am I missing something obvious about the pickle spec? Am I doing
> something wrong? Or should I be hunting for a deeper bug in the code?

Your class definition isn't right. It makes 'value' and 'journal'
class variables (Java lingo: "static variables") as opposed to the
instance variables they should be. Here's a corrected version:

class InitGame(object):
    def __init__(self):
        #instance variables are created through self.foo assignments in __init__
        self.value = False
        self.journal = []

Cheers,
Chris
--
http://blog.rebertia.com


From vilya.harvey at gmail.com  Mon Jul 13 17:51:01 2009
From: vilya.harvey at gmail.com (Vilya Harvey)
Date: Mon, 13 Jul 2009 22:51:01 +0100
Subject: Memory error due to big input file
In-Reply-To: <4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
	<mailman.3067.1247518893.8015.python-list@python.org>
	<4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
Message-ID: <6aef848f0907131451h2ae1b83cs1eda1651e6db13@mail.gmail.com>

2009/7/13 Aaron Scott <aaron.hildebrandt at gmail.com>:
>> BTW, you should derive all your classes from something. ?If nothing
>> else, use object.
>> ? class textfile(object):
>
> Just out of curiousity... why is that? I've been coding in Python for
> a long time, and I never derive my base classes. What's the advantage
> to deriving them?

    class Foo:

uses the old object model.

    class Foo(object):

uses the new object model.

See http://docs.python.org/reference/datamodel.html (specifically
section 3.3) for details of the differences.

Vil.


From clp2 at rebertia.com  Mon Jul 13 18:02:37 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 15:02:37 -0700
Subject: Memory error due to big input file
In-Reply-To: <6aef848f0907131451h2ae1b83cs1eda1651e6db13@mail.gmail.com>
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
	<mailman.3067.1247518893.8015.python-list@python.org>
	<4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
	<6aef848f0907131451h2ae1b83cs1eda1651e6db13@mail.gmail.com>
Message-ID: <50697b2c0907131502p2e262a22p4a6af5a31bfee677@mail.gmail.com>

On Mon, Jul 13, 2009 at 2:51 PM, Vilya Harvey<vilya.harvey at gmail.com> wrote:
> 2009/7/13 Aaron Scott <aaron.hildebrandt at gmail.com>:
>>> BTW, you should derive all your classes from something. ?If nothing
>>> else, use object.
>>> ? class textfile(object):
>>
>> Just out of curiousity... why is that? I've been coding in Python for
>> a long time, and I never derive my base classes. What's the advantage
>> to deriving them?
>
> ? ?class Foo:
>
> uses the old object model.
>
> ? ?class Foo(object):
>
> uses the new object model.
>
> See http://docs.python.org/reference/datamodel.html (specifically
> section 3.3) for details of the differences.

Note that Python 3.0 makes explicitly subclassing `object` unnecessary
since it removes old-style classes; a class that doesn't explicitly
subclass anything will implicitly subclass `object`.

Cheers,
Chris
-- 
http://blog.rebertia.com


From aaron.hildebrandt at gmail.com  Mon Jul 13 19:00:18 2009
From: aaron.hildebrandt at gmail.com (Aaron Scott)
Date: Mon, 13 Jul 2009 16:00:18 -0700 (PDT)
Subject: Pickling classes -- disappearing lists?
References: <2a0cb6a2-558c-4ec4-9f88-21768682c902@n30g2000vba.googlegroups.com>
	<mailman.3068.1247521826.8015.python-list@python.org>
Message-ID: <60e9b0e3-25c7-4d01-a120-b15b33a06b57@m18g2000vbi.googlegroups.com>

> Your class definition isn't right. It makes 'value' and 'journal'
> class variables (Java lingo: "static variables") as opposed to the
> instance variables they should be. Here's a corrected version:
>

Woah, thanks. I can't believe I made such a stupid mistake. It's not
like I'm a newcomer to Python, either. I'm can't believe I never
noticed what I was doing.

No more 2am coding for me.

Thanks,
Aaron


From db3l.net at gmail.com  Mon Jul 13 19:05:05 2009
From: db3l.net at gmail.com (David Bolen)
Date: Mon, 13 Jul 2009 19:05:05 -0400
Subject: PDF: finding a blank image
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
Message-ID: <m2tz1gdw0u.fsf@valheru.db3l.homeip.net>

DrLeif <l.lensgraf at gmail.com> writes:

> What I would like to do is have python detect a "blank" pages in a PDF
> file and remove it.  Any suggestions?

The odds are good that even a blank page is being "rendered" within
the PDF as having some small bits of data due to scanner resolution,
imperfections on the page, etc..  So I suspect you won't be able to just
look for a well-defined pattern in the resulting PDF or anything.

Unless you're using OCR, the odds are good that the scanner is
rendering the PDF as an embedded image.  What I'd probably do is
extract the image of the page, and then use image processing on it to
try to identify blank pages.  I haven't had the need to do this
myself, and tool availability would depend on platform, but for
example, I'd probably try ImageMagick's convert operation to turn the
PDF into images (like PNGs).  I think Gimp can also do a similar
conversion, but you'd probably have to script it yourself.

Once you have an image of a page, you could then use something like
OpenCV to process the page (perhaps a morphology operation to remove
small noise areas, then a threshold or non-zero counter to judge
"blankness"), or probably just something like PIL depending on
complexity of the processing needed.

Once you identify a blank page, removing it could either be with pure
Python (there have been other posts recently about PDF libraries) or
with external tools (such as pdftk under Linux for example).

-- David


From Scott.Daniels at Acm.Org  Mon Jul 13 19:22:23 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Mon, 13 Jul 2009 16:22:23 -0700
Subject: PDF: finding a blank image
In-Reply-To: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
Message-ID: <h7udnSUJcYlyIsbXnZ2dnUVZ_vWdnZ2d@pdx.net>

DrLeif wrote:
> I have about 6000 PDF files which have been produced using a scanner
> with more being produced each day.  The PDF files contain old paper
> records which have been taking up space.   The scanner is set to
> detect when there is information on the backside of the page (duplex
> scan).  The problem of course is it's not the always reliable and we
> wind up with a number of PDF files containing blank pages.
> 
> What I would like to do is have python detect a "blank" pages in a PDF
> file and remove it.  Any suggestions?

I'd check into ReportLab's commercial product, it may well be easily
capable of that.  If no success, you might contact PJ at Groklaw, she
has dealt with a _lot_ of PDFs (and knows people who deal with PDFs
in bulk).

--Scott David Daniels
Scott.Daniels at Acm.Org


From Brian.Mingus at colorado.edu  Mon Jul 13 19:26:26 2009
From: Brian.Mingus at colorado.edu (Brian)
Date: Mon, 13 Jul 2009 17:26:26 -0600
Subject: PDF: finding a blank image
In-Reply-To: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
Message-ID: <9839a05c0907131626w77489e62raf1582a9ff429a8f@mail.gmail.com>

Perhaps your blank pages have a characteristic size. Or perhaps if you trim
them with `convert' (ImageMagick) there is nothing left.

On Mon, Jul 13, 2009 at 3:44 PM, DrLeif <l.lensgraf at gmail.com> wrote:

> I have about 6000 PDF files which have been produced using a scanner
> with more being produced each day.  The PDF files contain old paper
> records which have been taking up space.   The scanner is set to
> detect when there is information on the backside of the page (duplex
> scan).  The problem of course is it's not the always reliable and we
> wind up with a number of PDF files containing blank pages.
>
> What I would like to do is have python detect a "blank" pages in a PDF
> file and remove it.  Any suggestions?
>
>
> Thanks,
> DrL
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/170847bf/attachment-0001.html>

From bjorn.m.meyer at gmail.com  Mon Jul 13 19:35:00 2009
From: bjorn.m.meyer at gmail.com (Bjorn Meyer)
Date: Mon, 13 Jul 2009 17:35:00 -0600
Subject: multiprocessing and dictionaries
In-Reply-To: <m2ab381jot.fsf@cs.uu.nl>
References: <mailman.3031.1247418982.8015.python-list@python.org>
	<mailman.3056.1247503227.8015.python-list@python.org>
	<m2ab381jot.fsf@cs.uu.nl>
Message-ID: <200907131735.00191.bjorn.m.meyer@gmail.com>


On Monday 13 July 2009 13:12:18 Piet van Oostrum wrote:

> >>>>> Bjorn Meyer <bjorn.m.meyer at gmail.com> (BM) wrote:
> >
> >BM> Here is what I have been using as a test.
> >BM> This pretty much mimics what I am trying to do.
> >BM> I put both threading and multiprocessing in the example which shows
> >BM> the output that I am looking for.
> >
> >BM> #!/usr/bin/env python
> >
> >BM> import threading
> >BM> from multiprocessing import Manager, Process
> >
> >BM> name = ('test1','test2','test3')
> >BM> data1 = ('dat1','dat2','dat3')
> >BM> data2 = ('datA','datB','datC')
>
> [snip]
>
> >BM> def multiprocess_test(name,data1,data2, mydict):
> >BM>   for nam in name:
> >BM>     for num in range(0,3):
> >BM>       mydict.setdefault(nam, []).append(data1[num])
> >BM>       mydict.setdefault(nam, []).append(data2[num])
> >BM>   print 'Multiprocess test dic:',mydict
>
> I guess what's happening is this:
>
> d.setdefault(nam, []) returns a list, initially an empty list ([]). This
> list gets appended to. However, this list is a local list in the
> multi-process_test Process, therefore the result is not reflected in the
> original list inside the manager. Therefore all your updates get lost.
> You will have to do operations directly on the dictionary itself, not on
> any intermediary objects. Of course with the threading the situation is
> different as all operations are local.
>
> This works:
>
> def multiprocess_test(name,data1,data2, mydict):
>   print name, data1, data2
>   for nam in name:
>     for num in range(0,3):
>       mydict.setdefault(nam, [])
>       mydict[nam] += [data1[num]]
>       mydict[nam] += [data2[num]]
>   print 'Multiprocess test dic:',mydict
>
> If you have more than one process operating on the dictionary
> simultaneously you have to beware of race conditions!!
> --
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org

Excellent. That works perfectly.

Thank you for your response Piet.

Bjorn




From ben+python at benfinney.id.au  Mon Jul 13 20:09:06 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 14 Jul 2009 10:09:06 +1000
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <87eiskktwd.fsf@benfinney.id.au>

seldan24 <seldan24 at gmail.com> writes:

> I'm fairly new at Python so hopefully this question won't be too
> awful.  I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).

You have been given a lot of advice so far about catching exceptions
with the ?try ? except? syntax. But reading your request, I think
perhaps you don't want to catch exceptions at all.

Instead of catching *all* exceptions at a specific point in your code,
and then having nothing to do but end the program (possibly after some
pre-exit action like logging), I think you would be better served by
installing a custom top-level exception handler.

    When an exception is raised and uncaught, the interpreter calls
    sys.excepthook with three arguments, the exception class, exception
    instance, and a traceback object. In an interactive session this
    happens just before control is returned to the prompt; in a Python
    program this happens just before the program exits. The handling of
    such top-level exceptions can be customized by assigning another
    three-argument function to sys.excepthook.

    <URL:http://docs.python.org/library/sys#sys.excepthook>

With a custom top-level exception handler in place, you should then
restrict your use of ?try: ? except FooException: ?? to be as precise
as possible, so that the ?try? block is as small as possible and the
?FooException? is as specific as possible.

Any other exceptions that you don't specifically catch will then go
through to your default handle-it-just-before-we-exit ?sys.excepthook?
exception handler.

-- 
 \         ?Nature hath given men one tongue but two ears, that we may |
  `\          hear from others twice as much as we speak.? ?Epictetus, |
_o__)                                                      _Fragments_ |
Ben Finney


From pavlovevidence at gmail.com  Mon Jul 13 20:49:23 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 13 Jul 2009 17:49:23 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
Message-ID: <4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>

On Jul 13, 12:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> seldan24 <selda... at gmail.com> (s) wrote:
> >s> Hello,
> >s> I'm fairly new at Python so hopefully this question won't be too
> >s> awful. ?I am writing some code that will FTP to a host, and want to
> >s> catch any exception that may occur, take that and print it out
> >s> (eventually put it into a log file and perform some alerting action).
> >s> I've figured out two different ways to do this, and am wondering which
> >s> is the best (i.e. cleanest, 'right' way to proceed). ?I'm also trying
> >s> to understand exactly what occurs for each one.
> >s> The first example:
> >s> from ftplib import FTP
> >s> try:
> >s> ? ? ftp = FTP(ftp_host)
> >s> ? ? ftp.login(ftp_user, ftp_pass)
> >s> except Exception, err:
> >s> ? ? print err
>
> I think you should restrict yourself to those exceptions that are
> related to ftp. Do you want to catch an exception like a misspelling in
> one of the variables?

He quite reasonably could want that, such as if the program is
designed to be run from a cron job, or in some other non-interactive
way.

Just because something is usually a bad idea doesn't mean it always
is.


Carl Banks


From albert at spenarnc.xs4all.nl  Mon Jul 13 22:28:06 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 14 Jul 2009 02:28:06 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
Message-ID: <kmr2uu.d1t@spenarnc.xs4all.nl>

In article <7x8wj4uxnb.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>
>Anyway, Python's overloading of bool(...) is yet another misfeature
>and although it's convenient, the "explicit is better than implicit"
>principle indicates to avoid that sort of trick.

Well, trading "tricks" (I would call it idiom) for explicitness,
made some people (you know ..) hate Pascal.
Einstein introduced the summation convention for indices that
are used twice. Leaving out summation signs is absolutely hideous,
but it has saved generations of physicists of loosing track (and
their minds.)

Also ...

For me there is nothing more clear than a regular expression
search that returns None if nothing matches.

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From albert at spenarnc.xs4all.nl  Mon Jul 13 22:46:19 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 14 Jul 2009 02:46:19 GMT
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<7xy6r34f3j.fsf@ruckus.brouhaha.com>
	<0260bf8d$0$20657$c3e8da3@news.astraweb.com>
	<7x8wj2agma.fsf@ruckus.brouhaha.com>
Message-ID: <kmr3p7.d9a@spenarnc.xs4all.nl>

In article <7x8wj2agma.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx at NOSPAM.invalid> wrote:
>Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> > but I don't accept that "somethingness"
>> > vs. "nothingness" is the same distinction as truth vs falsehood.
>>
>> It's the distinction used by Python since the dawn of time. Python only
>> grew a bool type a few versions back.
>
>That's true, part of the situation we have now is an artifact of that
>history.
>
>> I'm not talking about the constants True and False (nouns), but about
>> true and false values (adjectives).
>
>But, it seems to me, the constants True and False are the only values
>to which the adjectives "true" and "false" should be applicable to.
>
>>
>> > The idea that the "if"
>> > statement selects between "somethingness" and "nothingness" rather than
>> > between True and False is a bogus re-imagining of the traditional
>> > function of an "if" statement
>>
>> There's nothing bogus about it.
>>
>> > and has been an endless source of bugs in Python code.
>> I wonder why these "endless" bugs weren't important enough to be
>> mentioned in the rationale to PEP 285:
>
>Because adding the bool type doesn't really fix those bugs.
>
>> describing `if x` as the "correct form" and calling scrapping such a
>> feature as "crippling the language".
>
>Certainly, changing "if" would have broken an immense amount of code
>and been a completely unworkable approach.  We are using a fairly
>mature language by now; it has a culture and history that carries
>certain baggage, as one should expect.
>
>> > Look how much confusion it causes here in the newsgroup all the time.
>> The only confusion is that you're causing me. Would you care to link to
>> some?
>
>This current discussion (about bools) came from such confusion just a
>few posts up in this very thread:
>
>    From: upwestdon <upwestdon at gmail.com>
>    Date: Fri, 3 Jul 2009 23:03:39 -0700 (PDT)
>    How about just:
>
>    if not (self.higher and self.lower):
>        return self.higher or self.lower
>
>That test was designed to treat None as a boolean False, without
>noticing that numeric 0 is also treated as False and could make the
>test do the wrong thing.  This is an extremely common type of error.
>
>> > could see some value to having a generic "is_empty" predicate
>> We have that already. It's spelled __bool__ or __nonzero__
>
>That's fine, but under the "explicit is better than implicit"
>principle, it's preferable to call that predicate explicitly:
>"if bool(x): ..." rather than "if x:".  Also, after many years of

Maybe I'm missing something here, but if self.higher contains 0,
wouldn't bool(self.higher) evaluate to False?
So how does this help?

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:25:52 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:25:52 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
Message-ID: <pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>

On Mon, 13 Jul 2009 17:49:23 -0700, Carl Banks wrote:

> On Jul 13, 12:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
>> >>>>> seldan24 <selda... at gmail.com> (s) wrote:
>> >s> Hello,
>> >s> I'm fairly new at Python so hopefully this question won't be too s>
>> >awful. ?I am writing some code that will FTP to a host, and want to s>
>> >catch any exception that may occur, take that and print it out s>
>> >(eventually put it into a log file and perform some alerting action).
>> >s> I've figured out two different ways to do this, and am wondering
>> >which s> is the best (i.e. cleanest, 'right' way to proceed). ?I'm
>> >also trying s> to understand exactly what occurs for each one. s> The
>> >first example:
>> >s> from ftplib import FTP
>> >s> try:
>> >s> ? ? ftp = FTP(ftp_host)
>> >s> ? ? ftp.login(ftp_user, ftp_pass) s> except Exception, err:
>> >s> ? ? print err
>>
>> I think you should restrict yourself to those exceptions that are
>> related to ftp. Do you want to catch an exception like a misspelling in
>> one of the variables?
> 
> He quite reasonably could want that, such as if the program is designed
> to be run from a cron job, or in some other non-interactive way.


Why is it okay for non-interactive programs to silently have incorrect 
behaviour?

What's the point of a cron job that doesn't do what it is supposed to, 
because it has a bug which is silently swallowed?



"I find it amusing when novice programmers believe their main job is 
preventing programs from crashing. ... More experienced programmers 
realize that correct code is great, code that crashes could use 
improvement, but incorrect code that doesn't crash is a horrible 
nightmare."

http://www.pphsg.org/cdsmith/types.html




-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:27:30 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:27:30 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<87eiskktwd.fsf@benfinney.id.au>
Message-ID: <pan.2009.07.14.03.27.30@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 10:09:06 +1000, Ben Finney wrote:

> Instead of catching *all* exceptions at a specific point in your code,
> and then having nothing to do but end the program (possibly after some
> pre-exit action like logging), I think you would be better served by
> installing a custom top-level exception handler.
...
> Any other exceptions that you don't specifically catch will then go
> through to your default handle-it-just-before-we-exit ?sys.excepthook?
> exception handler.



Isn't that risky though? Won't that potentially change the exception-
handling behaviour of functions and classes he imports from other modules?




-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:45:02 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:45:02 GMT
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com>
	<h32i2o$eop$1@reader1.panix.com> <h37gv5$r81$1@panix3.panix.com>
	<h3bagu$52m$4@lust.ihug.co.nz> <h3bogf$oo0$1@panix3.panix.com>
	<h3f5dt$dld$3@lust.ihug.co.nz>
Message-ID: <pan.2009.07.14.03.45.03@REMOVE.THIS.cybersource.com.au>

On Mon, 13 Jul 2009 23:22:36 +1200, Lawrence D'Oliveiro wrote:

[stupidity omitted]
> Nope, still doesn't work...


Are we supposed to interpret that post as Dumb Insolence or just Dumb?



-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 13 23:49:30 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 03:49:30 GMT
Subject: Memory error due to big input file
References: <a029b9d20907131010u1c11260ao6808ad19257aab4d@mail.gmail.com>
	<mailman.3067.1247518893.8015.python-list@python.org>
	<4f490b14-86b5-45e6-9b27-4d4f82c669bb@r25g2000vbn.googlegroups.com>
Message-ID: <pan.2009.07.14.03.49.31@REMOVE.THIS.cybersource.com.au>

On Mon, 13 Jul 2009 14:20:13 -0700, Aaron Scott wrote:

>> BTW, you should derive all your classes from something. ?If nothing
>> else, use object.
>> ? class textfile(object):
> 
> Just out of curiousity... why is that? I've been coding in Python for a
> long time, and I never derive my base classes. What's the advantage to
> deriving them?

"Old style" classes (those whose base classes aren't derived from 
anything) have a few disadvantages:


(1) Properties don't work correctly:

>>> class Parrot:  # old-style class
...     def __init__(self):
...             self._x = 3
...     def _setter(self, value):
...             self._x = value
...     def _getter(self):
...             print "Processing ..."
...             return self._x + 1
...     x = property(_getter, _setter)
...
>>> p = Parrot()
>>> p.x
Processing ...
4
>>> p.x = 2
>>> p.x
2

In general, anything that uses the descriptor protocol, not just 
property, will fail to work correctly with old-style classes.


(2) Classes using multiple inheritance with diamond-shaped inheritance 
will be broken.

(3) __slots__ is just an attribute.

(4) super() doesn't work.

And, depending on whether you consider this a disadvantage or an 
advantage:

(5) Special methods like __len__ can be over-ridden on the instance, not 
just the class:

>>> class K:
...     def __len__(self):
...             return 0
...
>>> k = K()
>>> len(k)
0
>>> k.__len__ = lambda : 42
>>> len(k)
42



In their favour:

(1) Less typing.

(2) If you're not using descriptors, including property(), or multiple 
inheritance with diamond diagrams, they work fine.

(3) They're (apparently) a tiny bit faster.



-- 
Steven


From Lily.Gao at autodesk.com  Tue Jul 14 00:30:03 2009
From: Lily.Gao at autodesk.com (Lily Gao)
Date: Mon, 13 Jul 2009 21:30:03 -0700
Subject: How to unbuffer Python's output
Message-ID: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>

Hi, All
I am calling a python program in perl and use redirection,
Like :
`python x.py > 1.log 2>&1`
When x.py crash, I get nothing from 1.log, and if I don?t use redirection, I can get useful log from the screen.
How can I do to make x.py ?s  output un-buffered when redirection log to files ,just exactly same with print to the screen?

When I use perl?s $|=1 to unbuffer output, it take no effect. So I think it may be caused by python.
Thanks!

Thanks,
Lily Gao(??)
ACRD PSEB Catapult TD
+86-21-38664379

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090713/45488094/attachment-0001.html>

From gagsl-py2 at yahoo.com.ar  Tue Jul 14 01:06:04 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 14 Jul 2009 02:06:04 -0300
Subject: How to check if any item from a list of strings is in a big
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>
Message-ID: <op.uw1kgeg9x6zn5v@gabriel.sleipnir-bsas>

En Mon, 13 Jul 2009 10:11:09 -0300, denis <denis-bz-gg at t-online.de>  
escribi?:

> Matt, how many words are you looking for, in how long a string ?
> Were you able to time any( substr in long_string ) against re.compile
> ( "|".join( list_items )) ?

There is a known algorithm to solve specifically this problem  
(Aho-Corasick), a good implementation should perform better than R.E. (and  
better than the gen.expr. with the advantage of returning WHICH string  
matched)
There is a C extension somewhere implementing Aho-Corasick.

-- 
Gabriel Genellina



From clp2 at rebertia.com  Tue Jul 14 01:32:55 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 22:32:55 -0700
Subject: explode()
In-Reply-To: <eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
Message-ID: <50697b2c0907132232g40dce2c3o776a2f07ef28acf0@mail.gmail.com>

On Mon, Jul 13, 2009 at 11:28 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
> On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
> wrote:
>
>>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>>
>>some_string.split("separator")
>>
>>Cheers,
>>Chris
>
> ? ? What would the equivalent of the PHP function implode be?

"separator".join(a_list_of_strings)

I would recommend you read the Python manual's section on string methods:
http://docs.python.org/library/stdtypes.html#string-methods

Cheers,
Chris
-- 
http://blog.rebertia.com


From usernet at ilthio.net  Tue Jul 14 01:41:40 2009
From: usernet at ilthio.net (Tim Harig)
Date: Tue, 14 Jul 2009 05:41:40 GMT
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
Message-ID: <oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com>

On 2009-07-14, Fred Atkinson <fatkinson at mishmash.com> wrote:
> 	The one thing I really dislike about Python over PHP is that
> Python can usually only appear in the cgi directory (unless other
> arragements are made with your hosting provider or if you reconfigure
> Apache on your own server if you have your own).  With PHP, I can put
> them in any folder on my Web site without any problem.  

That is a server configuration and has nothing to do with Python directly.


From sanu1267 at gmail.com  Tue Jul 14 01:41:52 2009
From: sanu1267 at gmail.com (sanju ps)
Date: Tue, 14 Jul 2009 11:11:52 +0530
Subject: python _binary_ code
Message-ID: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>

Hi

 Can anyone give me solution to create a python binary file (bytecode) other
than pyc file .So my source code be secure.. I am working on ubuntu 9.04
with python2.6.. I

Regards
Sanju
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/1d418def/attachment-0001.html>

From clp2 at rebertia.com  Tue Jul 14 02:00:00 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 13 Jul 2009 23:00:00 -0700
Subject: python _binary_ code
In-Reply-To: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
References: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
Message-ID: <50697b2c0907132300xd593feepbaf5a2be078c93f4@mail.gmail.com>

On Mon, Jul 13, 2009 at 10:41 PM, sanju ps<sanu1267 at gmail.com> wrote:
> Hi
>
> ?Can anyone give me solution to create a python binary file (bytecode) other
> than pyc file .So my source code be secure.. I am working on ubuntu 9.04
> with python2.6.. I

PyInstaller (http://www.pyinstaller.org/) will generate a
self-contained executable, but it won't hide the bytecode (which can
be decompiled w/ decompyle).
It's generally accepted to be impossible (or at least more trouble
than it's worth) to protect Python source.

See http://stackoverflow.com/questions/261638/how-do-i-protect-python-code
for excellent and more detailed answers.

Cheers,
Chris
-- 
http://blog.rebertia.com


From fatkinson at mishmash.com  Tue Jul 14 02:28:32 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Mon, 13 Jul 2009 23:28:32 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
Message-ID: <eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>

On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
wrote:

>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>
>some_string.split("separator")
>
>Cheers,
>Chris

     What would the equivalent of the PHP function implode be?  

	Thanks, 




					Fred 


From fatkinson at mishmash.com  Tue Jul 14 02:36:26 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Mon, 13 Jul 2009 23:36:26 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
Message-ID: <6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>

On Mon, 13 Jul 2009 22:32:55 -0700, Chris Rebert <clp2 at rebertia.com>
wrote:

>On Mon, Jul 13, 2009 at 11:28 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>> On Sat, 11 Jul 2009 18:50:28 -0700, Chris Rebert <clp2 at rebertia.com>
>> wrote:
>>
>>>On Sat, Jul 11, 2009 at 7:41 PM, Fred Atkinson<fatkinson at mishmash.com> wrote:
>>>> ? ? ? ?What is the Python equivalent of the PHP explode() function?
>>>
>>>some_string.split("separator")
>>>
>>>Cheers,
>>>Chris
>>
>> ? ? What would the equivalent of the PHP function implode be?
>
>"separator".join(a_list_of_strings)
>
>I would recommend you read the Python manual's section on string methods:
>http://docs.python.org/library/stdtypes.html#string-methods
>
>Cheers,
>Chris

Chris, 

	You always seem to be waiting when I post a question.  Do you
ever sleep?  

	I wish the Python site was as well written as the PHP site. On
the PHP site, I can look up a command and they show not only the docs
on that command but a list of all other commands associated with it.  

	Thanks.  Python is a whole new animal to me.  I'm taking a
course in PHP and Python online right now.  I've done PHP scripting
before though I don't claim to be a whiz on it.  But I'd barely heard
of Python before I took this course.  

	The one thing I really dislike about Python over PHP is that
Python can usually only appear in the cgi directory (unless other
arragements are made with your hosting provider or if you reconfigure
Apache on your own server if you have your own).  With PHP, I can put
them in any folder on my Web site without any problem.  

	Regards, 




						Fred 


From lists at cheimes.de  Tue Jul 14 02:50:16 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 14 Jul 2009 08:50:16 +0200
Subject: python _binary_ code
In-Reply-To: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
References: <2b76be80907132241q170bb040j827f8c75155188b1@mail.gmail.com>
Message-ID: <h3h9r9$39t$1@ger.gmane.org>

sanju ps schrieb:
> Hi
> 
>  Can anyone give me solution to create a python binary file (bytecode) other
> than pyc file .So my source code be secure.. I am working on ubuntu 9.04
> with python2.6.. I

It's impossible to secure your code if it runs on an untrusted computer.
This is true for all programming languages but it's even easier to
decompile code of byte interpreted languages like Python, Java or .NET.

Microsoft has tried to protect its programs, the film industry has tried
it with the movies and RIAA, too. All have failed. You won't have more
luck, though. :)

Christian



From wuwei23 at gmail.com  Tue Jul 14 02:54:11 2009
From: wuwei23 at gmail.com (alex23)
Date: Mon, 13 Jul 2009 23:54:11 -0700 (PDT)
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org> 
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org> 
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
Message-ID: <e47c89c6-3e16-48c1-b257-c53642fd9c0b@13g2000prl.googlegroups.com>

Fred Atkinson <fatkin... at mishmash.com> wrote:
> ? ? ? ? I wish the Python site was as well written as the PHP site. On
> the PHP site, I can look up a command and they show not only the docs
> on that command but a list of all other commands associated with it. ?

Hey Fred,

My problem is the complete opposite, I wish I could as easily
interrogate objects in PHP about their behaviour as I can Python :)

In case you're not familiar with this, you can see what methods are
attached to an object using the intepreter via dir() and see the
associated docstring for them via help(). Try looking at 'dir(str)'
for a list of methods that strings recognise, then 'help(str.join)' to
see the help on join.

This is such a handy ability to have that I miss this casual
introspection in everything else in which I'm required to develop.

Hope this helps.


From amrita at iisermohali.ac.in  Tue Jul 14 02:57:29 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Tue, 14 Jul 2009 12:27:29 +0530 (IST)
Subject: copy a file
Message-ID: <14186.210.212.36.65.1247554649.squirrel@www.iisermohali.ac.in>


Dear all,

Can anyone tell me that suppose i want to copy few lines from one text
file to another then how can i do that.Looking forward for soon reply.

Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From ben+python at benfinney.id.au  Tue Jul 14 02:59:07 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 14 Jul 2009 16:59:07 +1000
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<87eiskktwd.fsf@benfinney.id.au>
	<pan.2009.07.14.03.27.30@REMOVE.THIS.cybersource.com.au>
Message-ID: <873a8zlphg.fsf@benfinney.id.au>

Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:

> Isn't that risky though? Won't that potentially change the exception-
> handling behaviour of functions and classes he imports from other
> modules?

No, any existing ?except? clause will be unaffected by re-binding
?sys.excepthook?. As I understand the documentation, that function is
called only if the exception is uncaught by anything else.

    >>> 1 / 0
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    ZeroDivisionError: integer division or modulo by zero

    >>> import sys
    >>> def reverse_handler(exc_type, exc_instance, exc_traceback):
    ...     print exc_type.__name__[::-1], str(exc_instance)[::-1]
    ...
    >>> sys.excepthook = reverse_handler

    >>> try:
    ...     1 / 0
    ... except ZeroDivisionError:
    ...     print "You created a black hole."
    ... 
    You created a black hole.
    >>> 1 / 0
    rorrEnoisiviDoreZ orez yb oludom ro noisivid regetni

In other words, it is the function that (unless re-bound) prints the
traceback we're all familiar with when an exception is uncaught. It is
exposed via the name ?sys.excepthook? precisely for the purpose of
changing the default handler for uncaught exceptions

-- 
 \         ?I have yet to see any problem, however complicated, which, |
  `\      when you looked at it in the right way, did not become still |
_o__)                                more complicated.? ?Paul Anderson |
Ben Finney


From hackingkk at gmail.com  Tue Jul 14 03:07:13 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Tue, 14 Jul 2009 12:37:13 +0530
Subject: copy a file
In-Reply-To: <14186.210.212.36.65.1247554649.squirrel@www.iisermohali.ac.in>
References: <14186.210.212.36.65.1247554649.squirrel@www.iisermohali.ac.in>
Message-ID: <1247555233.3329.18.camel@krishna-laptop>

On Tue, 2009-07-14 at 12:27 +0530, amrita at iisermohali.ac.in wrote:
> Dear all,
> 
> Can anyone tell me that suppose i want to copy few lines from one text
> file to another then how can i do that.Looking forward for soon reply.
> 

very simple.  open one file and open the source file.
seek till to the point where u want to start copying and loop till the
end with readline function.
then write it to the destination file.

To find the starting point, keep looping through the content and come
out of that loop when you find a match to the word you are looking for.
happy hacking.
Krishnakant.



From pavlovevidence at gmail.com  Tue Jul 14 04:30:48 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 01:30:48 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
Message-ID: <93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>

On Jul 13, 8:25?pm, Steven D'Aprano
<ste... at REMOVE.THIS.cybersource.com.au> wrote:
> On Mon, 13 Jul 2009 17:49:23 -0700, Carl Banks wrote:
> > On Jul 13, 12:31?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >> >>>>> seldan24 <selda... at gmail.com> (s) wrote:
> >> >s> Hello,
> >> >s> I'm fairly new at Python so hopefully this question won't be too s>
> >> >awful. ?I am writing some code that will FTP to a host, and want to s>
> >> >catch any exception that may occur, take that and print it out s>
> >> >(eventually put it into a log file and perform some alerting action).
> >> >s> I've figured out two different ways to do this, and am wondering
> >> >which s> is the best (i.e. cleanest, 'right' way to proceed). ?I'm
> >> >also trying s> to understand exactly what occurs for each one. s> The
> >> >first example:
> >> >s> from ftplib import FTP
> >> >s> try:
> >> >s> ? ? ftp = FTP(ftp_host)
> >> >s> ? ? ftp.login(ftp_user, ftp_pass) s> except Exception, err:
> >> >s> ? ? print err
>
> >> I think you should restrict yourself to those exceptions that are
> >> related to ftp. Do you want to catch an exception like a misspelling in
> >> one of the variables?
>
> > He quite reasonably could want that, such as if the program is designed
> > to be run from a cron job, or in some other non-interactive way.
>
> Why is it okay for non-interactive programs to silently have incorrect
> behaviour?
>
> What's the point of a cron job that doesn't do what it is supposed to,
> because it has a bug which is silently swallowed?

Seriously, do you *ever* take more than 2 seconds to consider whether
you might be missing something obvious before following up with these
indignant knee-jerk responses?

I never said a thing about swallowing errors.  I was talking about
catching exceptions, whence you might do all kinds of things besides
swallowing (like logging).  I was pointing out there are reasons why
you might want to catch variable misspelling errors when you're
running non-interactively (like for instance, to log the error
somewhere).

Or would you rather let all unexpected exceptions print to standard
error, which is often a black hole in non-interactive sitations?


Carl Banks


From nelson1977 at gmail.com  Tue Jul 14 04:34:10 2009
From: nelson1977 at gmail.com (nelson -)
Date: Tue, 14 Jul 2009 10:34:10 +0200
Subject: Remote audio recording in a multiuser environment
Message-ID: <f44750160907140134g6b3c0aeh7fcddf6a3187c070@mail.gmail.com>

Hi all!
   I'm developing an application that will be used in a school. It
will allow client connected over ssh to liste to a multimedia file on
the server. The server componente will record the audio taken from a
specified client microphone, or it would pair two client, allowing
them to communicate each other registering the conversation.

I think to use pygst to record the microphone, but i can' figure out
how to register remote sound and how to create the channel between two
client. Do you think i have to use twisted (i don't know this
framework at all), or there is a simple solution?

I will surely use wxpython for the UI on the client and on the server.

Thank for any advice,
  nelson

-- 
Consulenze Linux e Windows

http://nelsonenterprise.net


From tedwards at it.dcs.ch  Tue Jul 14 05:11:13 2009
From: tedwards at it.dcs.ch (Tim Edwards)
Date: Tue, 14 Jul 2009 11:11:13 +0200
Subject: 'unable to execute cc: No such file or directory' with distutils
	on Solaris
Message-ID: <4A5C4BB1.4050204@it.dcs.ch>

Hi,

I'm trying to compile http://sourceforge.net/projects/astlib/ 0.17.1 on
a Solaris 10 SPARC system. This python module uses distutils.ccompiler.
The problem seems to be that although I have gcc installed in
/usr/sfw/bin/gcc it keeps trying to execute the command 'cc', which
doesn't work:

cc -c actread.c -o actread.o
unable to execute cc: No such file or directory
error: command 'cc' failed with exit status 1


I've tried modifying the setup.py file to specify "cc.compiler =
'/usr/sfw/bin/gcc'" and setting the $CC envrionment var.
But I get the same error everytime. Can someone suggest how to change
where distutils is looking for the compiler?

Thanks

Tim Edwards


From rileycrane at gmail.com  Tue Jul 14 05:12:15 2009
From: rileycrane at gmail.com (R C)
Date: Tue, 14 Jul 2009 02:12:15 -0700 (PDT)
Subject: MySQLdb + SSH Tunnel
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
Message-ID: <d01ebee4-543e-4f13-9e8e-33ccd08ce24e@o13g2000vbl.googlegroups.com>

Got it working.  Thanks for your help

1) login to B
2) setup a tunnel in the shell   machine-B> ssh -L
B_ip_address:B_port:C_ip_address:C_port user at C_ip_address

   for example:
     machine-B has ip 1.1.1.1
     machine-C has ip 2.2.2.2

   then I would type:
   machine-B> ssh -L 1.1.1.1:3307:2.2.2.2:3306 user at 2.2.2.2

   now the code that is running on machine-A would use MySQLdb in the
following way

   import MySQLdb
   connection = MySQLdb.connect
(user='myname',passwd='mypass',db='mydb',host='1.1.1.1',port=3307)

   NOTE: the port is an integer, NOT a string



On Jul 12, 9:18?pm, Riley Crane <vodkal... at gmail.com> wrote:
> OVERVIEW:
> I am running a script on one machine that connects to a MySQL database
> on another machine that is outside of our university's domain.
> According to the administrator, network policies do not allow the
> compute nodes to access machines outside of our university's domain.
>
> COMPUTERS:
> A = compute node within university (I do not have shell access)
> B = 2nd machine within university that does not block outside
> connections (I have root access)
> C = machine outside of university (I have root access)
> mysqldb on A cannot connect to C ....but.....
> mysqldb on A can connect to B
>
> WHAT I WOULD LIKE TO DO:
> Is it possible to set something up where A talks to a port on B, and
> that port is actually nothing more than 3306 on C? ?Can I do this with
> an SSH tunnel?
>
> Can anyone please give precise instructions?



From vodkalove at gmail.com  Tue Jul 14 05:14:19 2009
From: vodkalove at gmail.com (Riley Crane)
Date: Tue, 14 Jul 2009 02:14:19 -0700 (PDT)
Subject: MySQLdb + SSH Tunnel
References: <171b01cc-201e-407c-97c4-34556cfa3035@j21g2000vbn.googlegroups.com>
Message-ID: <03687615-f8b2-427f-af2d-4cfcb23604f8@f33g2000vbm.googlegroups.com>

Got it working.  Thanks for your help!

1) login to B
2) setup a tunnel in the shell   machine-B> ssh -L
B_ip_address:B_port:C_ip_address:C_port user at C_ip_address

   for example:
     machine-B has ip 1.1.1.1
     machine-C has ip 2.2.2.2

   then I would type:
   machine-B> ssh -L 1.1.1.1:3307:2.2.2.2:3306 user at 2.2.2.2

   now the code that is running on machine-A would use MySQLdb in the
following way

   import MySQLdb
   connection = MySQLdb.connect
(user='myname',passwd='mypass',db='mydb',host='1.1.1.1',port=3307)

   NOTE: the port is an integer, NOT a string


On Jul 12, 9:18?pm, Riley Crane <vodkal... at gmail.com> wrote:
> OVERVIEW:
> I am running a script on one machine that connects to a MySQL database
> on another machine that is outside of our university's domain.
> According to the administrator, network policies do not allow the
> compute nodes to access machines outside of our university's domain.
>
> COMPUTERS:
> A = compute node within university (I do not have shell access)
> B = 2nd machine within university that does not block outside
> connections (I have root access)
> C = machine outside of university (I have root access)
> mysqldb on A cannot connect to C ....but.....
> mysqldb on A can connect to B
>
> WHAT I WOULD LIKE TO DO:
> Is it possible to set something up where A talks to a port on B, and
> that port is actually nothing more than 3306 on C? ?Can I do this with
> an SSH tunnel?
>
> Can anyone please give precise instructions?



From steven at REMOVE.THIS.cybersource.com.au  Tue Jul 14 05:14:52 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 14 Jul 2009 09:14:52 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
Message-ID: <pan.2009.07.14.09.14.52@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 01:30:48 -0700, Carl Banks wrote:

> Seriously, do you *ever* take more than 2 seconds to consider whether
> you might be missing something obvious before following up with these
> indignant knee-jerk responses?

Obviously not.


[...]
> Or would you rather let all unexpected exceptions print to standard
> error, which is often a black hole in non-interactive sitations?

Fair point. Of course you're right.



-- 
Steven


From hartley79 at gmail.com  Tue Jul 14 05:22:24 2009
From: hartley79 at gmail.com (hartley)
Date: Tue, 14 Jul 2009 02:22:24 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com>
Message-ID: <51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com>

> > I'm very new at wrapping Python/C, and I have run into some problems.
>
> > I have one python module that provides me with a list (provideBuffer
> > in provideBuff.py):
>
> > ?Py_Initialize();
> > ? ? ? ? pName = PyString_FromString("provideBuff");
> > ? ? ? ? pModule = PyImport_Import(pName);
>
> > ? ? ? ? pFunc = PyObject_GetAttrString(pModule,"provideBuffer");
>
> > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > pValue is now a PyList - i've even verified this with:
>
> > int a = PyList_Check(pValue);
> > ? ? ? ? printf("%d\n", a);
>
> > However, I want to send this PyList to another python module,
>
> Please explain "send" ... do you mean the C equivalent of the Python
> statement C_embedding.buff = the_pylist ?
>
> BTW C-embedding would trigger a syntax error in Python source; best to
> avoid ...


I'm sorry I'm not using the proper terms when trying to describe this
- i've never really learnt those terms, I guess i should do that one
day.


Imagine that the python function C-embedding.buff looks like this:

def buff(a):
    if isinstance(a,list):
        print "success"

I want to send, pass, call, whatever a list argument from the C code
onto this function. As simple as this - how can you call a function in
python from C, and providing a python list as an argument?

As I wrote earlier - I already have a PyList, called pValue. But I
have not been able to use this as an argument for C-embedding.buff
using the code I described last time.


> > but I
> > don't know how to do this. Initially I though I could just do like
> > above, only swapping NULL with pValue, but that is not working.
>
> > pName2 = PyString_FromString("C-embedding");
> > pModule2 = PyImport_Import(pName2);
> > pFunc2 = PyObject_GetAttrString(pModule2,"buff");
>
> Get?? Do you want Set? Is buff a Python function? Or is it the
> destination of the "sending"? Any good reason for not checking the
> return value for an error? [Rhetorical question; answer == "No"]
>
> > pValue2 = PyObject_CallObject(pFunc2,pValue);
>
> CallObject?? You used this before because you had a function and
> wanted to call it because it returned you a value .... now you want to
> do one of (in Python terms)
>
> value = amodule.anattr
> value = getattr(amodule, "anattr")
>
> or
>
> amodule.anattr = value
> setattr(amodule, "anattr", value)
>
> > pValue2 is now False!
>
> False?? Do you mean the C NULL?
>
> > So i guess i cannot pass pValue as an argument
> > to PyObject_CallObject when i want to pass an python list as an
> > argument. But how must a go about to make this work?
>
> It's mainly just a matter of (1) knowing what you want to do (2)
> picking the API that does what you want (3) checking the returned
> value for error after every call.
>
> HTH,
> John



From clp2 at rebertia.com  Tue Jul 14 05:25:15 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 02:25:15 -0700
Subject: How to unbuffer Python's output
In-Reply-To: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
References: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
Message-ID: <50697b2c0907140225s59df742fpdfb2673d837e4f3d@mail.gmail.com>

2009/7/13 Lily Gao <Lily.Gao at autodesk.com>:
> Hi, All
>
> I am calling a python program in perl and use redirection,
>
> Like :
>
> `python x.py > 1.log 2>&1`
>
> When x.py crash, I get nothing from 1.log, and if I don?t use redirection, I
> can get useful log from the screen.
>
> How can I do to make x.py ?s? output un-buffered when redirection log to
> files ,just exactly same with print to the screen?

Use the -u flag to python:
?u    Force stdin, stdout and stderr to be totally unbuffered.

python -u x.py > 1.log 2>&1

Cheers,
Chris
-- 
http://blog.rebertia.com


From amrita at iisermohali.ac.in  Tue Jul 14 05:43:17 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Tue, 14 Jul 2009 15:13:17 +0530 (IST)
Subject: copy a few lines
Message-ID: <23461.210.212.36.65.1247564597.squirrel@www.iisermohali.ac.in>



Dear all,

I want to know if i want to copy one paragraph from one text file to
another then what command i have to use in python.Looking forwaard for
soon reply.


Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From clp2 at rebertia.com  Tue Jul 14 05:50:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 02:50:13 -0700
Subject: copy a few lines
In-Reply-To: <23461.210.212.36.65.1247564597.squirrel@www.iisermohali.ac.in>
References: <23461.210.212.36.65.1247564597.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907140250lb2bdc63y4872c522cf216953@mail.gmail.com>

On Tue, Jul 14, 2009 at 2:43 AM, <amrita at iisermohali.ac.in> wrote:
>
>
> Dear all,
>
> I want to know if i want to copy one paragraph from one text file to
> another then what command i have to use in python.Looking forwaard for
> soon reply.

Please don't double-post. It wastes everyone's time, especially when
(a) your previous post was less than 3 hours ago, and
(b) your previous post got a response.

If you're refining your question, it's best to just reply to your own
prior post.

Also, you're going to need to define what precisely qualifies as a
"paragraph" for your purposes.

- Chris
-- 
http://blog.rebertia.com


From jon at peirce.org.uk  Tue Jul 14 06:28:19 2009
From: jon at peirce.org.uk (JonPeirce)
Date: Tue, 14 Jul 2009 03:28:19 -0700 (PDT)
Subject: renice
In-Reply-To: <1193438701.979110.114360@v3g2000hsg.googlegroups.com>
References: <13422771.post@talk.nabble.com>
	<1193417206.734440.268840@o38g2000hse.googlegroups.com>
	<1193438701.979110.114360@v3g2000hsg.googlegroups.com>
Message-ID: <24477000.post@talk.nabble.com>



Note that with os.nice you can only *decrease* priority. For increasing
priority you need to run;
os.system("sudo renice -n %s %s" % (new_nice, os.getpid()))
or simply set the nice level when you run python in the first place (you do
also need sudo for this):
sudo nice -n -15 python myScript.py

Jon
-- 
View this message in context: http://www.nabble.com/renice-tp13422771p24477000.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From hartley79 at gmail.com  Tue Jul 14 06:32:08 2009
From: hartley79 at gmail.com (hartley)
Date: Tue, 14 Jul 2009 03:32:08 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com>
Message-ID: <3d3d9f7e-5c57-414b-9363-f1ebfca0f9e2@r25g2000vbn.googlegroups.com>

On Jul 13, 6:35?pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 14, 1:47?am, hartley <hartle... at gmail.com> wrote:
>
>
>
> > I'm very new at wrapping Python/C, and I have run into some problems.
>
> > I have one python module that provides me with a list (provideBuffer
> > in provideBuff.py):
>
> > ?Py_Initialize();
> > ? ? ? ? pName = PyString_FromString("provideBuff");
> > ? ? ? ? pModule = PyImport_Import(pName);
>
> > ? ? ? ? pFunc = PyObject_GetAttrString(pModule,"provideBuffer");
>
> > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > pValue is now a PyList - i've even verified this with:
>
> > int a = PyList_Check(pValue);
> > ? ? ? ? printf("%d\n", a);
>
> > However, I want to send this PyList to another python module,
>
> Please explain "send" ... do you mean the C equivalent of the Python
> statement C_embedding.buff = the_pylist ?
>
> BTW C-embedding would trigger a syntax error in Python source; best to
> avoid ...
>
> > but I
> > don't know how to do this. Initially I though I could just do like
> > above, only swapping NULL with pValue, but that is not working.
>
> > pName2 = PyString_FromString("C-embedding");
> > pModule2 = PyImport_Import(pName2);
> > pFunc2 = PyObject_GetAttrString(pModule2,"buff");
>
> Get?? Do you want Set? Is buff a Python function? Or is it the
> destination of the "sending"? Any good reason for not checking the
> return value for an error? [Rhetorical question; answer == "No"]
>
> > pValue2 = PyObject_CallObject(pFunc2,pValue);
>
> CallObject?? You used this before because you had a function and
> wanted to call it because it returned you a value .... now you want to
> do one of (in Python terms)
>
> value = amodule.anattr
> value = getattr(amodule, "anattr")
>
> or
>
> amodule.anattr = value
> setattr(amodule, "anattr", value)
>
> > pValue2 is now False!
>
> False?? Do you mean the C NULL?
>
> > So i guess i cannot pass pValue as an argument
> > to PyObject_CallObject when i want to pass an python list as an
> > argument. But how must a go about to make this work?
>
> It's mainly just a matter of (1) knowing what you want to do (2)
> picking the API that does what you want (3) checking the returned
> value for error after every call.
>
> HTH,
> John

I tried to keep this simple, but I realise that since I'm not using
the terminology correctly, it may be hard understand what I mean.

I'll do something even simpler:

Say you have the function:

C-embedding.buff

def buff(s):
	if isinstance(s,list):
           return s

how can i call (use,invoke,?? - sorry, about the terminology again)
this function from C so that I call this function with an argument
that is (accepted as) a python list?

foo.bar

def bar():


pName = PyString_FromString("foo");
pModule = PyImport_Import(pName);
pFunc = PyObject_GetAttrString(pModule,"bar");
pValue = PyObject_CallObject(pFunc,NULL);


From dana_at_work at yahoo.com  Tue Jul 14 07:32:35 2009
From: dana_at_work at yahoo.com (dana)
Date: Tue, 14 Jul 2009 04:32:35 -0700 (PDT)
Subject: DBI module deprecated at Python 2.5--what to use in its place?
References: <338f4e72-72c2-4121-86be-fad0af20e47e@h11g2000yqb.googlegroups.com>
	<mailman.2960.1247242538.8015.python-list@python.org>
Message-ID: <9e63df1c-9757-4e94-98a0-f49b383a3ad6@h30g2000vbr.googlegroups.com>

On Jul 10, 12:15?pm, "M.-A. Lemburg" <m... at egenix.com> wrote:
> If you're looking for a stable and maintained ODBC for Python,
> have a look at our mxODBC extension or mxODBC Connect package:
> http://www.egenix.com/products/python/mxODBC/http://www.egenix.com/products/python/mxODBCConnect/

I'm looking for a free module. Is yours a commercial product?

Thanks.

Dana


From torf at torfbold.com  Tue Jul 14 07:38:45 2009
From: torf at torfbold.com (Florian Brucker)
Date: Tue, 14 Jul 2009 13:38:45 +0200
Subject: Efficient binary search tree stored in a flat array?
In-Reply-To: <5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
Message-ID: <4a5c5e7f$0$30235$9b4e6d93@newsspool1.arcor-online.net>

Douglas Alan wrote:
> Thank you. My question wasn't intended to be Python specific, though.
> I am just curious for purely academic reasons about whether there is
> such an algorithm. All the sources I've skimmed only seem to the
> answer the question via omission. Which is kind of strange, since it
> seems to me like an obvious question to ask.

IIRC comp.programming would be the place to ask such questions.


HTH,
Florian


From __peter__ at web.de  Tue Jul 14 07:45:47 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 14 Jul 2009 13:45:47 +0200
Subject: Tkinter / Entry widget problem
References: <mailman.3066.1247516702.8015.python-list@python.org>
Message-ID: <h3hr54$p6s$02$1@news.t-online.com>

Andras Szabo wrote:

> Hello. I searched the archives but couldn't find a solution to a
> problem related to the Entry widget in Tkinter.
> 
> When creating a pop-up window in an app, which contains an Entry
> widget, I want this widget to contain some default string, to have all
> this default string selected (as if the user had manually selected
> everything), and to have the focus transferred to this widget.
> 
> (The idea is then that if the window pops up, the user won't have to
> click or press Tab any more before being able to type what is needed
> in the textbox, overwriting what is written there already.)
> 
> I thought this might be the way to go:
> 
> entrybox=Entry(toplevel_parent_window)
> entrybox.insert(0,"Some default string")
> entrybox.select_range(0,END)
> entrybox.focus_set()
> entrybox.pack()
> 
> But it doesn't seem to work - the focus is not transferred to the
> Entry widget, and the text does not appear to be selected (even though
> after this entrybox.selection_present() returns True).
> 
> What am I doing wrong?

Nothing, I would think. Can you post a minimal runnable example?

Peter



From ldo at geek-central.gen.new_zealand  Tue Jul 14 07:48:57 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 14 Jul 2009 23:48:57 +1200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
Message-ID: <h3hrb9$9c$2@lust.ihug.co.nz>

In message <93f6a517-63d8-4c80-
bf19-4614b70999db at m7g2000prd.googlegroups.com>, Carl Banks wrote:

> Or would you rather let all unexpected exceptions print to standard
> error, which is often a black hole in non-interactive sitations?

Since when?

Cron, for example, collects standard error and mails it to you.



From ldo at geek-central.gen.new_zealand  Tue Jul 14 07:50:34 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 14 Jul 2009 23:50:34 +1200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<mailman.3053.1247495610.8015.python-list@python.org>
	<d82cea0b-3327-4a27-b300-08975f7c0606@p28g2000vbn.googlegroups.com>
Message-ID: <h3hreb$9c$3@lust.ihug.co.nz>

In message <d82cea0b-3327-4a27-
b300-08975f7c0606 at p28g2000vbn.googlegroups.com>, seldan24 wrote:

> For this particular script, all exceptions are fatal
> and I would want them to be.  I just wanted a way to catch them and
> log them prior to program termination.

You don't need to. They will be written to standard error anyway.



From ldo at geek-central.gen.new_zealand  Tue Jul 14 07:52:40 2009
From: ldo at geek-central.gen.new_zealand (Lawrence D'Oliveiro)
Date: Tue, 14 Jul 2009 23:52:40 +1200
Subject: The meaning of "=" (Was: tough-to-explain Python)
References: <h3291j$mfu$1@reader1.panix.com> <h32i2o$eop$1@reader1.panix.com>
	<h37gv5$r81$1@panix3.panix.com> <h3bagu$52m$4@lust.ihug.co.nz>
	<h3bogf$oo0$1@panix3.panix.com> <h3f5dt$dld$3@lust.ihug.co.nz>
	<pan.2009.07.14.03.45.03@REMOVE.THIS.cybersource.com.au>
Message-ID: <h3hri9$9c$4@lust.ihug.co.nz>

In message <pan.2009.07.14.03.45.03 at REMOVE.THIS.cybersource.com.au>, Steven 
D'Aprano wrote:

> Are we supposed to interpret that post as Dumb Insolence or just Dumb?

"Insolence" indeed ... another wanker to plonk, I think.



From piet at cs.uu.nl  Tue Jul 14 08:10:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 14:10:20 +0200
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
Message-ID: <m2r5wjzcr7.fsf@cs.uu.nl>

>>>>> Douglas Alan <darkwater42 at gmail.com> (DA) wrote:

>DA> On Jul 13, 3:57?pm, a... at pythoncraft.com (Aahz) wrote:
>>> Still, unless your list is large (more than thousands of elements),
>>> that's the way you should go. ?See the bisect module. ?Thing is, the
>>> speed difference between C and Python means the constant for insertion
>>> and deletion is very very small relative to bytecode speed. ?Keep in
>>> mind that Python's object/binding model means that you're shuffling
>>> pointers in the list rather than items.

>DA> Thank you. My question wasn't intended to be Python specific, though.
>DA> I am just curious for purely academic reasons about whether there is
>DA> such an algorithm. All the sources I've skimmed only seem to the
>DA> answer the question via omission. Which is kind of strange, since it
>DA> seems to me like an obvious question to ask.

Of course you can take any BST algorithm and replace pointers by indices
in the array and allocate new elements in the array. But then you need
array elements to contain the indices for the children explicitely.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From sjmachin at lexicon.net  Tue Jul 14 08:21:30 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 05:21:30 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com>
Message-ID: <cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com>

On Jul 14, 7:22?pm, hartley <hartle... at gmail.com> wrote:
> > > I'm very new at wrapping Python/C, and I have run into some problems.
[snip]

> > > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > > pValue is now a PyList - i've even verified this with:
>
> > > int a = PyList_Check(pValue);
> > > ? ? ? ? printf("%d\n", a);
>
> > > However, I want to send this PyList to another python module,
>
> > Please explain "send" ... do you mean the C equivalent of the Python
> > statement C_embedding.buff = the_pylist ?
>
> > BTW C-embedding would trigger a syntax error in Python source; best to
> > avoid ...
>
> I'm sorry I'm not using the proper terms when trying to describe this
> - i've never really learnt those terms, I guess i should do that one
> day.

Today would be a good day to start :-)

>
> Imagine that the python function C-embedding.buff looks like this:
>
> def buff(a):
> ? ? if isinstance(a,list):
> ? ? ? ? print "success"
>
> I want to send, pass, call, whatever a list argument from the C code
> onto this function. As simple as this - how can you call a function in
> python from C, and providing a python list as an argument?
>
> As I wrote earlier - I already have a PyList, called pValue. But I
> have not been able to use this as an argument for C-embedding.buff
> using the code I described last time.
>
> > > but I
> > > don't know how to do this. Initially I though I could just do like
> > > above, only swapping NULL with pValue, but that is not working.
>
> > > pName2 = PyString_FromString("C-embedding");
> > > pModule2 = PyImport_Import(pName2);
> > > pFunc2 = PyObject_GetAttrString(pModule2,"buff");

> >  Any good reason for not checking the
> > return value for an error? [Rhetorical question; answer == "No"]
>
> > > pValue2 = PyObject_CallObject(pFunc2,pValue);

Your problem is here, in the second arg of PyObject_CallObject. It
should be either NULL if no args are being supplied, or a tuple
containing the args if 1 or more args are being supplied. pValue is
the arg itself; you need to wrap it in a tuple.

See http://docs.python.org/c-api/object.html#PyObject_CallObject

Actually you might like to use this instead (no tuple hassles):

http://docs.python.org/c-api/object.html#PyObject_CallFunctionObjArgs

What are you using as a source of information? Have you read this:

http://docs.python.org/extending/embedding.html#pure-embedding ?

It contains a very thorough example of calling a Python function from
C, with all the reference-counting and error-checking stuff and it's
quite runnable -- I've just now compiled it and run it (1) as-is (2)
changed to pass a list instead of multiple ints (3) changed again to
emulate you trying to pass the list directly instead of wrapped in a
tuple ... here's the result:

TypeError: argument list must be a tuple
Call failed

Oh by the way, you can get away with C-embedding as a module name if
you are importing it from C, but importing it from Python [so that you
could test it independently of your C program] presents a difficulty
(syntax error) ... better to change it to c_embedding.

> > It's mainly just a matter of (1) knowing what you want to do (2)
> > picking the API that does what you want (3) checking the returned
> > value for error after every call.

HTH,
John


From candide at free.invalid  Tue Jul 14 08:37:24 2009
From: candide at free.invalid (candide)
Date: Tue, 14 Jul 2009 14:37:24 +0200
Subject: Python code for testing well parenthesized expression
Message-ID: <4a5c7c04$0$16808$426a34cc@news.free.fr>

Hi,

I'm trying to implement in Python a function testing if an expression is well
parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik" is correctly
parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.

My code follows at the end.

If you have a better algorithm or a better Python code (I'm a beginner in the
Python world), don't hesitate ...



#----------------------------------

# The obvious iterative version
def i(s):
    op = 0 # op : open parenthesis
    for k in range(len(s)):
        op += (s[k] == '(') - (s[k] == ')')
        if op < 0: break
    return op


# Recursive implementation of the preceding version
def r(s,op=0): # op : open parenthesis
    if len(s)==0:
        return op
    elif s[0]=='(':
        return r(s[1:],op+1)
    elif s[0]==')':
        if op==0:
            return -1
        else :
            return r(s[1:],op-1)
    else :
        return r(s[1:],op)


# "functional" style version
def f(s):
    if (len(s)!=0 and s[0]=='('):
        z=f(s[1:])
        if len(z)!=0:
            return f(z[1:])
        else:
            return None
    elif len(s)==0 or s[0] == ')':
        return s
    else:
        return f(s[1:])


def test(t,f):
    for z in t:
        print (z,f(z)==0)

# True True True True True False False
t=["zx4er(1(er(Yy)ol)ol)ik",
"x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)",
"a(ty(y(y(bn)))lokl)kl",
"xc(er(tgy(rf(yh)()uj)ki))",
"e",
"rf(tgt)juj)jkik(jun)",
"zx(4er(1(er(Yy)ol)ol)ik"]

test(t,i)
print

test(t,r)
print

def test(t):
    for s in t: print (s,f(s)=="")

test(t)
#-------------------------------------------

and the corresponding output :


('zx4er(1(er(Yy)ol)ol)ik', True)
('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)', True)
('a(ty(y(y(bn)))lokl)kl', True)
('xc(er(tgy(rf(yh)()uj)ki))', True)
('e', True)
('rf(tgt)juj)jkik(jun)', False)
('zx(4er(1(er(Yy)ol)ol)ik', False)

('zx4er(1(er(Yy)ol)ol)ik', True)
('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)', True)
('a(ty(y(y(bn)))lokl)kl', True)
('xc(er(tgy(rf(yh)()uj)ki))', True)
('e', True)
('rf(tgt)juj)jkik(jun)', False)
('zx(4er(1(er(Yy)ol)ol)ik', False)

('zx4er(1(er(Yy)ol)ol)ik', True)
('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)', True)
('a(ty(y(y(bn)))lokl)kl', True)
('xc(er(tgy(rf(yh)()uj)ki))', True)
('e', True)
('rf(tgt)juj)jkik(jun)', False)
('zx(4er(1(er(Yy)ol)ol)ik', False)


From jeremy+complangpython at jeremysanders.net  Tue Jul 14 08:57:21 2009
From: jeremy+complangpython at jeremysanders.net (Jeremy Sanders)
Date: Tue, 14 Jul 2009 13:57:21 +0100
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <h3hvbh$sjl$1@gemini.csx.cam.ac.uk>

candide wrote:

> I'm trying to implement in Python a function testing if an expression is
> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
> 
> My code follows at the end.
> 
> If you have a better algorithm or a better Python code (I'm a beginner in
> the Python world), don't hesitate ...

Don't you want to just test that the number of "("s equals the number of 
")"s or am I missing the point?

>>> a='aAAA(bbb(cc)))'
>>> a.count('(') == a.count(')')

Jeremy

-- 
Jeremy Sanders
http://www.jeremysanders.net/



From adrian.dziubek at gmail.com  Tue Jul 14 08:59:51 2009
From: adrian.dziubek at gmail.com (Adrian Dziubek)
Date: Tue, 14 Jul 2009 05:59:51 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <c3635e15-37b1-431d-aeef-7b90f29a9c3d@f10g2000vbf.googlegroups.com>

Strings are immutable, so your method of slicing one letter at time
will be building lots of them. That shouldn't hurt you here, but it
will when you hit a bigger problem. In the i() there should be "return
op == 0" on the end.

def well(expr):
  mapping = {'(':1, ')':-1}
  count = 0
  for s in expr:
    if s in mapping:
      count += mapping[s]
    if s < 0:
      return False
  return count == 0

def test_well():
  examples = [
    ('zx4er(1(er(Yy)ol)ol)ik', True),
    ('x(x)x(x(x)xx(xx(x)x(x(x)xx)(xxxx))x(x(x)xx)(xxxx)x)(xxxx)',
True),
    ('a(ty(y(y(bn)))lokl)kl', True),
    ('xc(er(tgy(rf(yh)()uj)ki))', True),
    ('e', True),
    ('rf(tgt)juj)jkik(jun)', False),
    ('zx(4er(1(er(Yy)ol)ol)ik', False),
  ]
  for expr, expected in examples:
    assert well(expr) == expected


From adrian.dziubek at gmail.com  Tue Jul 14 09:04:06 2009
From: adrian.dziubek at gmail.com (Adrian Dziubek)
Date: Tue, 14 Jul 2009 06:04:06 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
Message-ID: <89cdf891-04e2-4c21-9043-cfdf91dd136a@j9g2000vbp.googlegroups.com>

> Don't you want to just test that the number of "("s equals the number of
> ")"s or am I missing the point?
I had this idea too, but there is additional requirement that any
beginning must have greater or equal number of '(' than ')'.
--
Adrian


From martin.hellwig at dcuktec.org  Tue Jul 14 09:05:38 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 14 Jul 2009 14:05:38 +0100
Subject: Python code for testing well parenthesized expression
In-Reply-To: <4a5c7c04$0$16808$426a34cc@news.free.fr>
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <YvGdnSP5s64-H8HXnZ2dnUVZ8u2dnZ2d@bt.com>

candide wrote:
To add to your implementations; a readable version:

+++file parantheses.py+++
"""Parentheses Module Test"""

def parentheses_are_paired(input_string):
     "Check if 'input_string' contains paired parentheses, if so return 
True."
     parenthesis_count = 0
     parenthesis_open = '('
     parenthesis_close = ')'

     for character in input_string:
         if character == parenthesis_open:
             parenthesis_count += 1
         elif character == parenthesis_close:
             parenthesis_count -= 1


     if parenthesis_count == 0:
         return(True)
     else:
         if parenthesis_count < 0:
             error_text = 'More closing parantheses than opening ones'

         elif parenthesis_count > 0:
             error_text = 'More opening parantheses than closing ones'

         raise(ValueError(error_text))

if __name__ == '__main__':
     TEST_TRUE = 'zx4er(1(er(Yy)ol)ol)ik'
     TEST_ERROR = 'zx(4er(1(er(Yy)ol)ol)ik'

     print(parentheses_are_paired(TEST_TRUE))

     try:
         print(parentheses_are_paired(TEST_ERROR))
     except(ValueError):
         print(False)

---file parantheses.py---

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From jeremy+complangpython at jeremysanders.net  Tue Jul 14 09:06:42 2009
From: jeremy+complangpython at jeremysanders.net (Jeremy Sanders)
Date: Tue, 14 Jul 2009 14:06:42 +0100
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
	<7c3dvuF25o0t6U1@mid.uni-berlin.de>
Message-ID: <h3hvt2$16t$1@gemini.csx.cam.ac.uk>

Diez B. Roggisch wrote:

> Yep, you are:
> 
> "())))((("
> 
> is certainly not "well parenthized".

Thanks for that!

-- 
Jeremy Sanders
http://www.jeremysanders.net/



From deets at nospam.web.de  Tue Jul 14 09:07:20 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 14 Jul 2009 15:07:20 +0200
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
Message-ID: <7c3dvuF25o0t6U1@mid.uni-berlin.de>

Jeremy Sanders wrote:

> candide wrote:
> 
>> I'm trying to implement in Python a function testing if an expression is
>> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
>> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
>> 
>> My code follows at the end.
>> 
>> If you have a better algorithm or a better Python code (I'm a beginner in
>> the Python world), don't hesitate ...
> 
> Don't you want to just test that the number of "("s equals the number of
> ")"s or am I missing the point?

Yep, you are:

"())))((("

is certainly not "well parenthized".

Diez


From dns4 at cornell.edu  Tue Jul 14 09:08:12 2009
From: dns4 at cornell.edu (David Smith)
Date: Tue, 14 Jul 2009 09:08:12 -0400
Subject: Python code for testing well parenthesized expression
In-Reply-To: <h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk>
Message-ID: <h3hvvu$o32$1@ruby.cit.cornell.edu>

Jeremy Sanders wrote:
> candide wrote:
> 
>> I'm trying to implement in Python a function testing if an expression is
>> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
>> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
>>
>> My code follows at the end.
>>
>> If you have a better algorithm or a better Python code (I'm a beginner in
>> the Python world), don't hesitate ...
> 
> Don't you want to just test that the number of "("s equals the number of 
> ")"s or am I missing the point?
> 
>>>> a='aAAA(bbb(cc)))'
>>>> a.count('(') == a.count(')')
> 
> Jeremy
> 

Using straight counting, )z))ab(c(ew( would be well parenthesized.  I
suspect a better way would be to iterate over the string using a balance
counter that increases 1 for every open, decreases 1 for every close.  A
negative balance at any moment would indicate an error as well as an
ending balance greater than 0.

--David


From martin.hellwig at dcuktec.org  Tue Jul 14 09:14:48 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 14 Jul 2009 14:14:48 +0100
Subject: Python code for testing well parenthesized expression
In-Reply-To: <YvGdnSP5s64-H8HXnZ2dnUVZ8u2dnZ2d@bt.com>
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<YvGdnSP5s64-H8HXnZ2dnUVZ8u2dnZ2d@bt.com>
Message-ID: <nIOdnRvpW_1UGcHXnZ2dnUVZ8sqdnZ2d@bt.com>

Martin P. Hellwig wrote:
> candide wrote:
> To add to your implementations; a readable version:
> 
> +++file parantheses.py+++
> """Parentheses Module Test"""
> 
> def parentheses_are_paired(input_string):
>     "Check if 'input_string' contains paired parentheses, if so return 
> True."
>     parenthesis_count = 0
>     parenthesis_open = '('
>     parenthesis_close = ')'
> 
>     for character in input_string:
>         if character == parenthesis_open:
>             parenthesis_count += 1
>         elif character == parenthesis_close:
>             parenthesis_count -= 1
> 
> 
>     if parenthesis_count == 0:
>         return(True)
>     else:
>         if parenthesis_count < 0:
>             error_text = 'More closing parantheses than opening ones'
> 
>         elif parenthesis_count > 0:
>             error_text = 'More opening parantheses than closing ones'
> 
>         raise(ValueError(error_text))
> 
> if __name__ == '__main__':
>     TEST_TRUE = 'zx4er(1(er(Yy)ol)ol)ik'
>     TEST_ERROR = 'zx(4er(1(er(Yy)ol)ol)ik'
> 
>     print(parentheses_are_paired(TEST_TRUE))
> 
>     try:
>         print(parentheses_are_paired(TEST_ERROR))
>     except(ValueError):
>         print(False)
> 
> ---file parantheses.py---
> 

However as Mr. Roggisch commented this wouldn't check if it is on the 
right spot, by moving the check that at any time you can not have more 
closing ones than opening ones within the loop you will get those 
exceptions too.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From sjmachin at lexicon.net  Tue Jul 14 09:14:50 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 13:14:50 +0000 (UTC)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
Message-ID: <loom.20090714T125851-382@post.gmane.org>

candide <candide <at> free.invalid> writes:

> # The obvious iterative version
> def i(s):
>     op = 0 # op : open parenthesis
>     for k in range(len(s)):
>         op += (s[k] == '(') - (s[k] == ')')
>         if op < 0: break
>     return op
> 

E: H c, w t P.
F: A c, b ? P.

Suggested better code:

def iterative(string):
    paren_count = 0
    for char in string:
        paren_count += (char == '(') - (char == ')')
        if paren_count < 0: break
    return paren_count

You don't need the other versions :-)

Try an iterative version of checking that () [] and {}
are balanced and nested appropriately.

Cheers,
John



From sjmachin at lexicon.net  Tue Jul 14 09:17:48 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 06:17:48 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<h3hvbh$sjl$1@gemini.csx.cam.ac.uk> 
	<h3hvvu$o32$1@ruby.cit.cornell.edu>
Message-ID: <e8195ead-f733-4107-a98b-b000170968d4@y28g2000prd.googlegroups.com>

On Jul 14, 11:08?pm, David Smith <d... at cornell.edu> wrote:
> Jeremy Sanders wrote:
> > candide wrote:
>
> >> I'm trying to implement in Python a function testing if an expression is
> >> well parenthesized. For instance the expression "zx4er(1(er(Yy)ol)ol)ik"
> >> is correctly parenthesized but this one "zx(4er(1(er(Yy)ol)ol)ik" is not.
>
> >> My code follows at the end.
>
> >> If you have a better algorithm or a better Python code (I'm a beginner in
> >> the Python world), don't hesitate ...
>
> > Don't you want to just test that the number of "("s equals the number of
> > ")"s or am I missing the point?
>
> >>>> a='aAAA(bbb(cc)))'
> >>>> a.count('(') == a.count(')')
>
> > Jeremy
>
> Using straight counting, )z))ab(c(ew( would be well parenthesized. ?I
> suspect a better way would be to iterate over the string using a balance
> counter that increases 1 for every open, decreases 1 for every close. ?A
> negative balance at any moment would indicate an error as well as an
> ending balance greater than 0.
>
> --David

Ummm isn't that the OP's first function?


From Scott.Daniels at Acm.Org  Tue Jul 14 09:19:37 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 06:19:37 -0700
Subject: Efficient binary search tree stored in a flat array?
In-Reply-To: <m2r5wjzcr7.fsf@cs.uu.nl>
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
Message-ID: <xcadneiIYYK1GcHXnZ2dnUVZ_qadnZ2d@pdx.net>

Piet van Oostrum wrote:
>>>>>> Douglas Alan <darkwater42 at gmail.com> (DA) wrote:
> 
>> DA> On Jul 13, 3:57 pm, a... at pythoncraft.com (Aahz) wrote:
>>>> Still, unless your list is large (more than thousands of elements),
>>>> that's the way you should go.  See the bisect module.  Thing is, the
>>>> speed difference between C and Python means the constant for insertion
>>>> and deletion is very very small relative to bytecode speed.  Keep in
>>>> mind that Python's object/binding model means that you're shuffling
>>>> pointers in the list rather than items.
> 
>> DA> Thank you. My question wasn't intended to be Python specific, though.
>> DA> I am just curious for purely academic reasons about whether there is
>> DA> such an algorithm. All the sources I've skimmed only seem to the
>> DA> answer the question via omission. Which is kind of strange, since it
>> DA> seems to me like an obvious question to ask.

It may well be that there is no good simple solution, and people avoid
writing about non-existent algorithms.  I certainly cannot imagine
trying to write an article that carefully covered ideas which don't
have well-studied data structures available, and calling them out
only to say, "we don't know how to do this well."  If such an algorithm
were simple and obvious, I dare say you'd be taught about it around the
time you learn binary search.

> Of course you can take any BST algorithm and replace pointers by indices
> in the array and allocate new elements in the array. But then you need
> array elements to contain the indices for the children explicitely.

And you loower your locality of reference (cache-friendliness).
Note the insert in Python, for example, is quite cache-friendly.

--Scott David Daniels
Scott.Daniels at Acm.Org


From aaron.watters at gmail.com  Tue Jul 14 09:23:23 2009
From: aaron.watters at gmail.com (Aaron Watters)
Date: Tue, 14 Jul 2009 06:23:23 -0700 (PDT)
Subject: WHIFF 0.4 += repoze.who authentication + menus + calculator + docs.
Message-ID: <1209aa77-c58c-4daf-a0f7-74f479ca59c8@f30g2000vbf.googlegroups.com>

WHIFF (WSGI HTTP Integrated Filesystem Frames) 0.4 released.

The new WHIFF 0.4 release linked from

    http://whiff.sourceforge.net

includes the following enhancements:

Built in support for repoze.who based authentication
(from http://static.repoze.org/whodocs/ ) + tutorial
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1100_1500.who .

AJAX calculator demo and tutorial:
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1100_1400.calc .

Built in drop-down menu support and tutorial:
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1100_1300.menus .

Some subtle but important bug fixes, including a thread
race condition bug fix.  Auto-reload support.

Also documentation improvements: particularly
for standard middleware
   see: http://aaron.oirt.rutgers.edu/myapp/docs/W1200_1400.stdMiddleware

What is WHIFF?

WHIFF is a collection of support services for Python WSGI
applications which allows applications to be composed
by "dropping" dynamic pages into container directories.
This mode of development will be familiar to developers
who have created PHP applications, vanilla CGI scripts,
Apache/modpy Publisher applications, JSP pages, or
static web content.

The WHIFF implementation significantly generalizes the
"drop in" paradigm to support WSGI middleware components
and application fragments as well as stand-alone pages.

WHIFF provides other services in addition to supporting
"drop in" components, such as managed application
resources.

I created WHIFF to address complexity issues I
encounter when creating and fixing sophisticated
Web applications which include complex database
interactions and dynamic features such as AJAX
(Asynchronous Javascript And XML).

Project home page:
   http://whiff.sourceforge.net .
Documentation index:
   http://aaron.oirt.rutgers.edu/myapp/docs/W.intro .

I hope you like it!

   -- Aaron Watters

===
% ping elvis
elvis is alive


From sjmachin at lexicon.net  Tue Jul 14 09:26:38 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 14 Jul 2009 13:26:38 +0000 (UTC)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<c3635e15-37b1-431d-aeef-7b90f29a9c3d@f10g2000vbf.googlegroups.com>
Message-ID: <loom.20090714T132012-442@post.gmane.org>

Adrian Dziubek <adrian.dziubek <at> gmail.com> writes:


> In the i() there should be "return
> op == 0" on the end.

Hard to tell. In the absence of any docs, we have to resort to divination on the
function name :-P ... is "i" short for "iterative" or "imbalanced"?





From l.lensgraf at gmail.com  Tue Jul 14 09:49:38 2009
From: l.lensgraf at gmail.com (DrLeif)
Date: Tue, 14 Jul 2009 06:49:38 -0700 (PDT)
Subject: PDF: finding a blank image
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
	<h7udnSUJcYlyIsbXnZ2dnUVZ_vWdnZ2d@pdx.net>
Message-ID: <736570b5-c315-4eb2-99d1-5de7f05c26d0@l28g2000vba.googlegroups.com>

On Jul 13, 6:22?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> DrLeif wrote:
> > I have about 6000 PDF files which have been produced using a scanner
> > with more being produced each day. ?The PDF files contain old paper
> > records which have been taking up space. ? The scanner is set to
> > detect when there is information on the backside of the page (duplex
> > scan). ?The problem of course is it's not the always reliable and we
> > wind up with a number of PDF files containingblankpages.
>
> > What I would like to do is have python detect a "blank" pages in a PDF
> > file and remove it. ?Any suggestions?
>
> I'd check into ReportLab's commercial product, it may well be easily
> capable of that. ?If no success, you might contact PJ at Groklaw, she
> has dealt with a _lot_ of PDFs (and knows people who deal with PDFs
> in bulk).
>
> --Scott David Daniels
> Scott.Dani... at Acm.Org



From aahz at pythoncraft.com  Tue Jul 14 09:54:07 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 06:54:07 -0700
Subject: Infinite loops and synchronization
References: <mailman.3048.1247462046.8015.python-list@python.org>
Message-ID: <h3i2lv$8em$1@panix3.panix.com>

In article <mailman.3048.1247462046.8015.python-list at python.org>,
Vincent Gulinao  <vincent.gulinao at gmail.com> wrote:
>
>lst = list()
>
>while True:
>	if len(lst) == SOME_NUMBER:
>		return lst
>
>Q2: operating on list from threads (mostly appends) must be safe,
>right (synchronization)?

What do you mean by "safe"?  Python certainly won't crash, but there's
no guarantee that the list will be consistent from *your* perspective.
Consider what happens if len(lst) == SOME_NUMBER - 1 and some other part
of your code adds two elements to lst.  You'll skip right over your if
condition.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From aahz at pythoncraft.com  Tue Jul 14 09:55:37 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 06:55:37 -0700
Subject: compilation problem of python on AIX 6.1
References: <51c556a8-7277-474d-821f-190adf155c75@f16g2000vbf.googlegroups.com>
Message-ID: <h3i2op$5if$1@panix3.panix.com>

In article <51c556a8-7277-474d-821f-190adf155c75 at f16g2000vbf.googlegroups.com>,
Amit  <amit.kumar.iitr at gmail.com> wrote:
>
>THen I decided to compile python 2.5.4 on my AIX box. I downloaded the
>python source code from www.python.org and tried to compile on my AIX
>both using gcc.
>
>	case $MAKEFLAGS in  *-s*)  CC='gcc -pthread' LDSHARED='./Modules/
>ld_so_aix gcc -pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -
>fwrapv -O3 -Wall -Wstrict-prototypes' ./python -E ./setup.py -q
>build;;  *)  CC='gcc -pthread' LDSHARED='./Modules/ld_so_aix gcc -
>pthread -bI:Modules/python.exp' OPT='-DNDEBUG -g -fwrapv -O3 -Wall -
>Wstrict-prototypes' ./python -E ./setup.py build;;  esac
>running build
>running build_ext
>building 'bz2' extension
>gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -
>Wstrict-prototypes -I. -I/avre/Python-2.5.4/./Include -I. -IInclude -
>I./Include -I/avre/Python-2.5.4/Include -I/avre/Python-2.5.4 -c /avre/
>Python-2.5.4/Modules/bz2module.c -o build/temp.aix-6.1-2.5/avre/
>Python-2.5.4/Modules/bz2module.o
>building '_tkinter' extension
>./Modules/ld_so_aix gcc -pthread -bI:Modules/python.exp build/
>temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/_tkinter.o build/
>temp.aix-6.1-2.5/avre/Python-2.5.4/Modules/tkappinit.o -L/usr/X11/lib -
>ltk8.4 -ltcl8.4 -lX11 -o build/lib.aix-6.1-2.5/_tkinter.so
>*** WARNING: renaming "_tkinter" since importing it failed: 	0509-022
>Cannot load module build/lib.aix-6.1-2.5.
>	0509-026 System error: A file or directory in the path name does not
>exist.

This looks like a generic AIX compilation error finding system libraries;
you probably will get better results from asking on an AIX forum.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From fatkinson at mishmash.com  Tue Jul 14 09:56:01 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Tue, 14 Jul 2009 06:56:01 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com>
Message-ID: <hi3p551ikld7d00c3dvs1vhkmnjgg8ffcn@4ax.com>

On Tue, 14 Jul 2009 05:41:40 GMT, Tim Harig <usernet at ilthio.net>
wrote:

>On 2009-07-14, Fred Atkinson <fatkinson at mishmash.com> wrote:
>> 	The one thing I really dislike about Python over PHP is that
>> Python can usually only appear in the cgi directory (unless other
>> arragements are made with your hosting provider or if you reconfigure
>> Apache on your own server if you have your own).  With PHP, I can put
>> them in any folder on my Web site without any problem.  
>
>That is a server configuration and has nothing to do with Python directly.

Agreed, it doesn't.  But if my hosting provider won't change it, I'm
stuck with it.  

Regards, 



 Fred 


From fatkinson at mishmash.com  Tue Jul 14 09:58:58 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Tue, 14 Jul 2009 06:58:58 -0700
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<e47c89c6-3e16-48c1-b257-c53642fd9c0b@13g2000prl.googlegroups.com>
Message-ID: <5k3p5514u11kldk56vjgpop4jp90hf3o89@4ax.com>

On Mon, 13 Jul 2009 23:54:11 -0700 (PDT), alex23 <wuwei23 at gmail.com>
wrote:

>Fred Atkinson <fatkin... at mishmash.com> wrote:
>> ? ? ? ? I wish the Python site was as well written as the PHP site. On
>> the PHP site, I can look up a command and they show not only the docs
>> on that command but a list of all other commands associated with it. ?
>
>Hey Fred,
>
>My problem is the complete opposite, I wish I could as easily
>interrogate objects in PHP about their behaviour as I can Python :)
>
>In case you're not familiar with this, you can see what methods are
>attached to an object using the intepreter via dir() and see the
>associated docstring for them via help(). Try looking at 'dir(str)'
>for a list of methods that strings recognise, then 'help(str.join)' to
>see the help on join.
>
>This is such a handy ability to have that I miss this casual
>introspection in everything else in which I'm required to develop.
>
>Hope this helps.

	I appreciate the information.  I'm halfway through a course in
PHP and Python.  We are given assignments and we have to write the
assignment in both languages.  

	I'll take a look at that as I work on this week's assignment
(I've only got a month to finish the course but I can probably take
some time to look at this.  

	Regards, 




					Fred 


From phonky at europe.com  Tue Jul 14 10:03:16 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 16:03:16 +0200
Subject: one-time factory in python for an experienced java guy
Message-ID: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>

Hi

I have searched all over and haven't found the solution
for my problem yet. I am new to python, and all the time realize I
do program python in java, which is not great.

Besides being a real-life problem, I want to
solve it as elegant as I can, using it to
also learn about python (I know I could just
hack something easy for now).

That's what I want to do.

I have an Account class.
An Account instance has to get an account number.
On instance creation, I want the account number to
be generated (I don't want callers to pass
the account # to ensure uniqueness):

class Account(object):
	def __init__(self, holder):
         	self.__accountnumber = self.__generate_account_number()

Now, I do not know yet how the account number scheme looks like.
For now, I just want to have an incremental number; later,
when going to production, we'll need the proper one.

Furthermore, as we plan to distribute the package, we want
to allow custom account numbering schemes. Thus, customers
should be able to plug in their own AccountNumberGenerator implementation.

For now, I have a generators.py module.

I have an AccountNumberGenerator base class,
all subclasses should implement "generate".

I have an IncrementalGenerator subclass.

So for now, I need to instantiate IncrementalGenerator,
allowing for a future module to plugin their own generator.

Any suggestions on how to do this?
Thanks so much!!!!


From l.lensgraf at gmail.com  Tue Jul 14 10:04:16 2009
From: l.lensgraf at gmail.com (DrLeif)
Date: Tue, 14 Jul 2009 07:04:16 -0700 (PDT)
Subject: PDF: finding a blank image
References: <d54a399e-d2cc-4510-a15a-37b78e805c1e@l32g2000vbp.googlegroups.com>
	<h7udnSUJcYlyIsbXnZ2dnUVZ_vWdnZ2d@pdx.net>
Message-ID: <6ba293b7-bba4-4d7b-ba3b-fb7901a2ea7d@e18g2000vbe.googlegroups.com>

On Jul 13, 6:22?pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> DrLeif wrote:
> > I have about 6000 PDF files which have been produced using a scanner
> > with more being produced each day. ?The PDF files contain old paper
> > records which have been taking up space. ? The scanner is set to
> > detect when there is information on the backside of the page (duplex
> > scan). ?The problem of course is it's not the always reliable and we
> > wind up with a number of PDF files containingblankpages.
>
> > What I would like to do is have python detect a "blank" pages in a PDF
> > file and remove it. ?Any suggestions?
>
> I'd check into ReportLab's commercial product, it may well be easily
> capable of that. ?If no success, you might contact PJ at Groklaw, she
> has dealt with a _lot_ of PDFs (and knows people who deal with PDFs
> in bulk).
>
> --Scott David Daniels
> Scott.Dani... at Acm.Org


Thanks everyone for the quick reply.

I had considered using ReportLab however, was uncertain about it's
ability to detect a blank page.

Scott, I'll drop an email to ReportLab and PJ....

Thanks again,
DrLeif


From jjposner at optimum.net  Tue Jul 14 10:07:52 2009
From: jjposner at optimum.net (John Posner)
Date: Tue, 14 Jul 2009 10:07:52 -0400
Subject: Tkinter / Entry widget problem
In-Reply-To: <mailman.11278.1247575203.8014.python-list@python.org>
References: <mailman.11278.1247575203.8014.python-list@python.org>
Message-ID: <4A5C9138.2020502@optimum.net>


> Andras Szabo wrote:
>
>   
>> Hello. I searched the archives but couldn't find a solution to a
>> problem related to the Entry widget in Tkinter.
>>
>> When creating a pop-up window in an app, which contains an Entry
>> widget, I want this widget to contain some default string, to have all
>> this default string selected (as if the user had manually selected
>> everything), and to have the focus transferred to this widget.
>>
>> (The idea is then that if the window pops up, the user won't have to
>> click or press Tab any more before being able to type what is needed
>> in the textbox, overwriting what is written there already.)
>>
>> I thought this might be the way to go:
>>
>> entrybox=Entry(toplevel_parent_window)
>> entrybox.insert(0,"Some default string")
>> entrybox.select_range(0,END)
>> entrybox.focus_set()
>> entrybox.pack()
>>
>> But it doesn't seem to work - the focus is not transferred to the
>> Entry widget, and the text does not appear to be selected (even though
>> after this entrybox.selection_present() returns True).
>>
>> What am I doing wrong?
>>     
>
> Nothing, I would think. Can you post a minimal runnable example?
>
> Peter

This works for me, on Windows and Linux:

  from Tkinter import *

  rt = Tk()
  rt.title("root window")
  pop = Toplevel()
  pop.title("second window")

  entrybox=Entry(pop)
  entrybox.insert(0,"Some default string")
  entrybox.select_range(0,END)
  entrybox.focus_set()
  entrybox.pack()

  rt.withdraw()
  rt.mainloop()


On Win/XP SP3:

  > python
  Python 2.6.1 (r261:67517, Dec  4 2008, 16:51:00) [MSC v.1500 32 bit
   (Intel)] on   win32
  Type "help", "copyright", "credits" or "license" for more information.
  >>> import Tkinter
  >>> Tkinter.TkVersion
  8.5
  >>> Tkinter.TclVersion
  8.5

On Ubuntu Linux (Ubu-SL 2.6.27.14-generic):

  $ python
  Python 2.6.1 (r261:67515, Jan  9 2009, 19:06:23)
  [GCC 4.3.2] on linux2
  Type "help", "copyright", "credits" or "license" for more information.
  >>> import Tkinter
  >>> Tkinter.TkVersion
  8.4000000000000004
  >>> Tkinter.TclVersion
  8.4000000000000004


-John



From piet at cs.uu.nl  Tue Jul 14 10:10:06 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 16:10:06 +0200
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org>
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com>
	<hi3p551ikld7d00c3dvs1vhkmnjgg8ffcn@4ax.com>
Message-ID: <m2ljmrz77l.fsf@cs.uu.nl>

>>>>> Fred Atkinson <fatkinson at mishmash.com> (FA) wrote:

>FA> On Tue, 14 Jul 2009 05:41:40 GMT, Tim Harig <usernet at ilthio.net>
>FA> wrote:

>>> On 2009-07-14, Fred Atkinson <fatkinson at mishmash.com> wrote:
>>>> The one thing I really dislike about Python over PHP is that
>>>> Python can usually only appear in the cgi directory (unless other
>>>> arragements are made with your hosting provider or if you reconfigure
>>>> Apache on your own server if you have your own).  With PHP, I can put
>>>> them in any folder on my Web site without any problem.  
>>> 
>>> That is a server configuration and has nothing to do with Python directly.

>FA> Agreed, it doesn't.  But if my hosting provider won't change it, I'm
>FA> stuck with it.  

That's a good reason to dislike your hosting provider, not a good reason
to dislike Python.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From stefan_ml at behnel.de  Tue Jul 14 10:27:48 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 14 Jul 2009 16:27:48 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
Message-ID: <4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>

phonky wrote:
> class Account(object):
>     def __init__(self, holder):
>             self.__accountnumber = self.__generate_account_number()
> 
> Now, I do not know yet how the account number scheme looks like.
> For now, I just want to have an incremental number; later,
> when going to production, we'll need the proper one.

Use a global variable in the module.

Stefan


From http  Tue Jul 14 10:33:26 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 07:33:26 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <7xzlb7wczt.fsf@ruckus.brouhaha.com>

Stefan Behnel <stefan_ml at behnel.de> writes:

> phonky wrote:
> > class Account(object):
> >     def __init__(self, holder):
> >             self.__accountnumber = self.__generate_account_number()
> > 
> > Now, I do not know yet how the account number scheme looks like.
> > For now, I just want to have an incremental number; later,
> > when going to production, we'll need the proper one.
> 
> Use a global variable in the module.

Yuch!  Don't use a global.  Try something like:

    import itertools

    class Account(object):
       def __init__(self, holder, gen=itertools.count()):
          self.__accountnumber = gen.next()


From phonky at europe.com  Tue Jul 14 10:34:30 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 16:34:30 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
Message-ID: <f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>

Stefan, thanks first of all

> Use a global variable in the module.

I have an account_number_generator variable in the module,
I got that hint from searching the web.

But where my stubborn java mind doesn't release me:
what does the variable contain? Do I create the actual
IncrementalGenerator object there? Or the super class?
Or just a string, which a factory method takes to
create the actual object?

What I especially don't get:
How will an external module overwrite that variable?

I fail to see, python being interpreted, how I can ensure
that a future module is being executed later, thus
overwriting the variable.

Thanks again.



From newport at freemail.hu  Tue Jul 14 10:38:42 2009
From: newport at freemail.hu (Andras Szabo)
Date: Tue, 14 Jul 2009 17:38:42 +0300
Subject: Tkinter / Entry widget problem
In-Reply-To: <4A5C9138.2020502@optimum.net>
References: <mailman.11278.1247575203.8014.python-list@python.org>
	<4A5C9138.2020502@optimum.net>
Message-ID: <A250B4AC-C159-4919-BCE4-14747CC2DBD6@freemail.hu>

So it's either that I use Python 2.5.1, or that I use it on a Mac.  
(John, your code still doesn't work the way it's supposed to here.) I  
guess I'll upgrade to 2.6.1 and see if it makes a difference. (The  
Tkinter/Tcl versions are the same for me.) Thanks for your help.

andras

On Jul 14, 2009, at 5:07 PM, John Posner wrote:

>
>> Andras Szabo wrote:
>>
>>
>>> Hello. I searched the archives but couldn't find a solution to a
>>> problem related to the Entry widget in Tkinter.
>>>
>>> When creating a pop-up window in an app, which contains an Entry
>>> widget, I want this widget to contain some default string, to have  
>>> all
>>> this default string selected (as if the user had manually selected
>>> everything), and to have the focus transferred to this widget.
>>>
>>> (The idea is then that if the window pops up, the user won't have to
>>> click or press Tab any more before being able to type what is needed
>>> in the textbox, overwriting what is written there already.)
>>>
>>> I thought this might be the way to go:
>>>
>>> entrybox=Entry(toplevel_parent_window)
>>> entrybox.insert(0,"Some default string")
>>> entrybox.select_range(0,END)
>>> entrybox.focus_set()
>>> entrybox.pack()
>>>
>>> But it doesn't seem to work - the focus is not transferred to the
>>> Entry widget, and the text does not appear to be selected (even  
>>> though
>>> after this entrybox.selection_present() returns True).
>>>
>>> What am I doing wrong?
>>>
>>
>> Nothing, I would think. Can you post a minimal runnable example?
>>
>> Peter
>
> This works for me, on Windows and Linux:
>
> from Tkinter import *
>
> rt = Tk()
> rt.title("root window")
> pop = Toplevel()
> pop.title("second window")
>
> entrybox=Entry(pop)
> entrybox.insert(0,"Some default string")
> entrybox.select_range(0,END)
> entrybox.focus_set()
> entrybox.pack()
>
> rt.withdraw()
> rt.mainloop()
>
>
> On Win/XP SP3:
>
> > python
> Python 2.6.1 (r261:67517, Dec  4 2008, 16:51:00) [MSC v.1500 32 bit
>  (Intel)] on   win32
> Type "help", "copyright", "credits" or "license" for more information.
> >>> import Tkinter
> >>> Tkinter.TkVersion
> 8.5
> >>> Tkinter.TclVersion
> 8.5
>
> On Ubuntu Linux (Ubu-SL 2.6.27.14-generic):
>
> $ python
> Python 2.6.1 (r261:67515, Jan  9 2009, 19:06:23)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> >>> import Tkinter
> >>> Tkinter.TkVersion
> 8.4000000000000004
> >>> Tkinter.TclVersion
> 8.4000000000000004
>
>
> -John
>
>



From http  Tue Jul 14 10:40:52 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 07:40:52 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
Message-ID: <7xab37l43v.fsf@ruckus.brouhaha.com>

phonky <phonky at europe.com> writes:
> But where my stubborn java mind doesn't release me: what does the
> variable contain? Do I create the actual IncrementalGenerator object
> there? Or the super class?  Or just a string, which a factory method
> takes to create the actual object?

Ugh, just forget everything you ever knew about java.  Do some Zen
exercises to erase your mind.  Then read a Python tutorial as if
you're starting from nothing.


From contact at xavierho.com  Tue Jul 14 10:52:55 2009
From: contact at xavierho.com (Xavier Ho)
Date: Tue, 14 Jul 2009 22:52:55 +0800
Subject: Why does extend() fail in this case, and what am I doing wrong?
Message-ID: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>

Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
The code is run at: http://codepad.org/wgLU4JZh

class A():
    def __init__(self):
        self.n = [1, 2, 3, 4, 5]

a = A()
print a.n
print a.n.extend([6, 7, 8, 9])

#Output:
#[1, 2, 3, 4, 5]
#None

I really don't know, but I'm probably missing something. Any pointers would
be great.

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/716ef38c/attachment-0001.html>

From phonky at europe.com  Tue Jul 14 10:55:56 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 16:55:56 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <7xab37l43v.fsf@ruckus.brouhaha.com>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
Message-ID: <23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>

Thanks Paul,

> Ugh, just forget everything you ever knew about java.  Do some Zen
> exercises to erase your mind.  Then read a Python tutorial as if
> you're starting from nothing.

Yeah, surely right, but easier said than done...
I'm working on it.

Taking your example.

import itertools

     class Account(object):
        def __init__(self, holder, gen=itertools.count()):
           self.__accountnumber = gen.next()

If you consider my python illiteracy,

"itertools.count(): Make an iterator that returns consecutive integers 
starting with n"

to me that sounds like that solves the increment issue, but what about
future modules wanting to plug in a different
numbering format, e.g. 205434.1234 or whatever?




From tn.pablo at gmail.com  Tue Jul 14 11:07:29 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Tue, 14 Jul 2009 10:07:29 -0500
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
Message-ID: <fdd00b510907140807n19110d2bo2066c335c3926939@mail.gmail.com>

This has been asked extensively before, here and elsewhere.

On Tue, Jul 14, 2009 at 09:52, Xavier Ho<contact at xavierho.com> wrote:
> Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
> The code is run at: http://codepad.org/wgLU4JZh
>
> class A():
> ??? def __init__(self):
> ??????? self.n = [1, 2, 3, 4, 5]
>
> a = A()
> print a.n
> print a.n.extend([6, 7, 8, 9])
>
> #Output:
> #[1, 2, 3, 4, 5]
> #None
>
> I really don't know, but I'm probably missing something. Any pointers would
> be great.
>
> Best regards,
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>



-- 
Pablo Torres N.


From mabdelkader at gmail.com  Tue Jul 14 11:07:59 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Tue, 14 Jul 2009 11:07:59 -0400
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch> 
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch> 
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <148918f0907140807i3b31f9b0u94fecf309eec5cdc@mail.gmail.com>

What Paul was trying to elaborate on is that have your customers or whomever
will use this implement their own generator protocol to generate whatever
number format they need. Paul just gave you an example with
itertools.count(), where it is an infinite generator that yields count+1
every time.

Read up on the iterator protocol, have your customers pass in a generator to
establish their own formats.
http://docs.python.org/library/stdtypes.html#iterator-types

This is much more elegant than AbstractCustomerRandomFormatGenerator..etc
which is what the reference to "erase everything from Java" is attempting to
relate.

--
mahmoud mack abdelkader
python powered
http://blog.mahmoudimus.com/
mahmoud at linux.com


On Tue, Jul 14, 2009 at 10:55 AM, phonky <phonky at europe.com> wrote:

> Thanks Paul,
>
>  Ugh, just forget everything you ever knew about java.  Do some Zen
>> exercises to erase your mind.  Then read a Python tutorial as if
>> you're starting from nothing.
>>
>
> Yeah, surely right, but easier said than done...
> I'm working on it.
>
> Taking your example.
>
> import itertools
>
>    class Account(object):
>       def __init__(self, holder, gen=itertools.count()):
>          self.__accountnumber = gen.next()
>
> If you consider my python illiteracy,
>
> "itertools.count(): Make an iterator that returns consecutive integers
> starting with n"
>
> to me that sounds like that solves the increment issue, but what about
> future modules wanting to plug in a different
> numbering format, e.g. 205434.1234 or whatever?
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/d8becbaf/attachment-0001.html>

From python at mrabarnett.plus.com  Tue Jul 14 11:13:43 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 16:13:43 +0100
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
Message-ID: <4A5CA0A7.7090800@mrabarnett.plus.com>

Xavier Ho wrote:
> Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
> The code is run at: http://codepad.org/wgLU4JZh
> 
> class A():
>     def __init__(self):
>         self.n = [1, 2, 3, 4, 5]
>        
> a = A()
> print a.n
> print a.n.extend([6, 7, 8, 9])
> 
> #Output:
> #[1, 2, 3, 4, 5]
> #None
> 
> I really don't know, but I'm probably missing something. Any pointers 
> would be great.
> 
The extend() method modifies the list in-place and returns None. Try
printing a.n after extending.


From http  Tue Jul 14 11:14:18 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 08:14:18 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <7xzlb7fgad.fsf@ruckus.brouhaha.com>

phonky <phonky at europe.com> writes:
> "itertools.count(): Make an iterator that returns consecutive integers
> starting with n"
> 
> to me that sounds like that solves the increment issue, but what about
> future modules wanting to plug in a different
> numbering format, e.g. 205434.1234 or whatever?

You'd write a different generator for that, and use it instead of
itertools.count.  E.g. (untested):

  def different_gen():
      a  = 201593.0768                  # initial number
      while True:
         yield '%.04f'% a
         a += 123.4567                  # increase in increments of this much


From __peter__ at web.de  Tue Jul 14 11:20:03 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 14 Jul 2009 17:20:03 +0200
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<4a5c95e4$0$31340$9b4e6d93@newsspool4.arcor-online.net>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <h3i7ms$n4c$01$1@news.t-online.com>

phonky wrote:

> Thanks Paul,
> 
>> Ugh, just forget everything you ever knew about java.  Do some Zen
>> exercises to erase your mind.  Then read a Python tutorial as if
>> you're starting from nothing.
> 
> Yeah, surely right, but easier said than done...
> I'm working on it.
> 
> Taking your example.
> 
> import itertools
> 
>      class Account(object):
>         def __init__(self, holder, gen=itertools.count()):
>            self.__accountnumber = gen.next()
> 
> If you consider my python illiteracy,
> 
> "itertools.count(): Make an iterator that returns consecutive integers
> starting with n"
> 
> to me that sounds like that solves the increment issue, but what about
> future modules wanting to plug in a different
> numbering format, e.g. 205434.1234 or whatever?

In that case you may want to stick with the class attribute:

>>> class Account(object):
...     def __init__(self):
...             self.account = self.next_account()
...     def __str__(self):
...             return "Account(number=%r)" % self.account
...     __repr__ = __str__
...
>>> from itertools import count
>>> Account.next_account = count(42).next
>>> a = Account()
>>> b = Account()
>>> a, b
(Account(number=42), Account(number=43))
>>> from uuid import uuid1
>>> Account.next_account = staticmethod(uuid1)
>>> c = Account()
>>> d = Account()
>>> c, d
(Account(number=UUID('b0f8dfc6-7087-11de-be16-001d923f29c5')), 
Account(number=UUID('b310c90e-7087-11de-be16-001d923f29c5')))

You can plug in arbitrary callables at runtime. The only complication I can 
see is that you may have to wrap them into a staticmethod to prevent python 
from passing the self reference. You can avoid that if you just use a global 
instead:

# account.py
next_account = ...
class Account(object):
   def __init__(self): self.number = next_account()

You can then set the factory elsewhere

# main.py
import account
account.next_account = ...
a = Account()

In general in python we like to keep simple things simple rather than 
creating a huge bureaucracy.

Peter



From ml at well-adjusted.de  Tue Jul 14 11:20:13 2009
From: ml at well-adjusted.de (Jochen Schulz)
Date: Tue, 14 Jul 2009 17:20:13 +0200
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
Message-ID: <20090714152012.GY31378@wasteland.homelinux.net>

Xavier Ho:
>
> Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
-- snip
> print a.n.extend([6, 7, 8, 9])

extend doesn't fail. It just returns None and extends the list in place.

In [1]: l = [1, 2, 3]

In [2]: l.extend([4, 5, 6])

In [3]: l
Out[3]: [1, 2, 3, 4, 5, 6]


J.
-- 
When I get home from the supermarket I don't know what to do with all the
plastic.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/a85f7b98/attachment-0001.sig>

From aahz at pythoncraft.com  Tue Jul 14 11:24:14 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 08:24:14 -0700
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<f2017$4a5c9776$d9a2f023$27613@news.hispeed.ch>
	<7xab37l43v.fsf@ruckus.brouhaha.com>
	<23406$4a5c9c7d$d9a2f023$27926@news.hispeed.ch>
Message-ID: <h3i7uu$9oe$1@panix3.panix.com>

In article <23406$4a5c9c7d$d9a2f023$27926 at news.hispeed.ch>,
phonky  <phonky at europe.com> wrote:
>
>import itertools
>
>     class Account(object):
>        def __init__(self, holder, gen=itertools.count()):
>           self.__accountnumber = gen.next()
>
>If you consider my python illiteracy,
>
>"itertools.count(): Make an iterator that returns consecutive integers 
>starting with n"
>
>to me that sounds like that solves the increment issue, but what about
>future modules wanting to plug in a different
>numbering format, e.g. 205434.1234 or whatever?

Here's what I would do:

class Account:
    gen = itertools.count
    gen_instance = None

    def __init__(self, holder):
        if self.gen_instance is None:
            self.__class__.gen_instance = self.gen()
        self._account = self.gen_instance()

Notice that I'm using only a single underscore for ``_account`` to make
inheritance simpler, and I'm using ``self`` to access class attributes
*except* when I need to *set* the class attribute, which requires
``self.__class__``.

Now anyone who wants to change the generator can simply do
module.Account.gen = other_gen 
and it will work as long as no Account() instances have been created (you
don't want the generator to change mid-stream, right?).
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From pdpinheiro at gmail.com  Tue Jul 14 11:35:40 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Tue, 14 Jul 2009 08:35:40 -0700 (PDT)
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
Message-ID: <f83064a1-49bd-4133-980c-ab847a0b3bdf@n30g2000vba.googlegroups.com>

On Jul 14, 3:03?pm, phonky <pho... at europe.com> wrote:
> Hi
>
> I have searched all over and haven't found the solution
> for my problem yet. I am new to python, and all the time realize I
> do program python in java, which is not great.
>
> Besides being a real-life problem, I want to
> solve it as elegant as I can, using it to
> also learn about python (I know I could just
> hack something easy for now).
>
> That's what I want to do.
>
> I have an Account class.
> An Account instance has to get an account number.
> On instance creation, I want the account number to
> be generated (I don't want callers to pass
> the account # to ensure uniqueness):
>
> class Account(object):
> ? ? ? ? def __init__(self, holder):
> ? ? ? ? ? ? ? ? self.__accountnumber = self.__generate_account_number()
>
> Now, I do not know yet how the account number scheme looks like.
> For now, I just want to have an incremental number; later,
> when going to production, we'll need the proper one.
>
> Furthermore, as we plan to distribute the package, we want
> to allow custom account numbering schemes. Thus, customers
> should be able to plug in their own AccountNumberGenerator implementation.
>
> For now, I have a generators.py module.
>
> I have an AccountNumberGenerator base class,
> all subclasses should implement "generate".
>
> I have an IncrementalGenerator subclass.
>
> So for now, I need to instantiate IncrementalGenerator,
> allowing for a future module to plugin their own generator.
>
> Any suggestions on how to do this?
> Thanks so much!!!!

You don't want an AccountNumberGenerator class and subclassing, all
you need is an iterator/generator of some form.

These might help:
http://docs.python.org/tutorial/classes.html#iterators
http://docs.python.org/tutorial/classes.html#generators
(in fact, that whole page is pretty relevant)

Once your code expects one of those, it's trivially easy to plug
something else in there.


From Scott.Daniels at Acm.Org  Tue Jul 14 11:44:04 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 08:44:04 -0700
Subject: Proposal: Decimal literals in Python.
In-Reply-To: <n46ai3t0biv5390r4ijhq6ddn9va47f197@4ax.com>
References: <4721ab28$0$1238$e4fe514c@dreader28.news.xs4all.nl>
	<1193438763.190428.134710@q5g2000prf.googlegroups.com>
	<87tzodii6i.fsf@benfinney.id.au>
	<1193494184.618613.81090@50g2000hsm.googlegroups.com>
	<n46ai3t0biv5390r4ijhq6ddn9va47f197@4ax.com>
Message-ID: <WN-dnXhGXtWYO8HXnZ2dnUVZ_j-dnZ2d@pdx.net>

Tim Roberts wrote:
> My favorite notation for this comes from Ada, which allows arbitrary bases
> from 2 to 16, and allows for underscores within numeric literals:
> 
>   x23_bin : constant :=  2#0001_0111#;
>   x23_oct : constant :=  8#27#;
>   x23_dec : constant := 10#23#;
>   x23_hex : constant := 16#17#;
And mine is one w/o the base 10 bias:
     .f.123 == 0x123
     .7.123 == 0o123
     .1.1101 == 0b1101
That is, .<largest allowed digit>.<digits>
-- show the base by showing base-1 in the base.
I actually built this into "OZ," an interpretter.

--Scott David Daniels
Scott.Daniels at Acm.Org


From pavlovevidence at gmail.com  Tue Jul 14 11:53:33 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 08:53:33 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<pan.2009.07.14.09.14.52@REMOVE.THIS.cybersource.com.au>
Message-ID: <ba24b9b8-f95d-4217-8e43-0fed8f4034b5@s6g2000vbp.googlegroups.com>

On Jul 14, 2:14?am, Steven D'Aprano
<ste... at REMOVE.THIS.cybersource.com.au> wrote:
> On Tue, 14 Jul 2009 01:30:48 -0700, Carl Banks wrote:
> > Seriously, do you *ever* take more than 2 seconds to consider whether
> > you might be missing something obvious before following up with these
> > indignant knee-jerk responses?
>
> Obviously not.
>
> [...]
>
> > Or would you rather let all unexpected exceptions print to standard
> > error, which is often a black hole in non-interactive sitations?
>
> Fair point. Of course you're right.

I don't want to be mean or anything.  I agree with you on 95% of
issues probably, of course I only follow up to disagree....

Carl Banks


From contact at xavierho.com  Tue Jul 14 11:54:05 2009
From: contact at xavierho.com (Xavier Ho)
Date: Tue, 14 Jul 2009 23:54:05 +0800
Subject: Why does extend() fail in this case, and what am I doing wrong?
In-Reply-To: <20090714152012.GY31378@wasteland.homelinux.net>
References: <2d56febf0907140752x2fe62cf2y9a542821059dd6cc@mail.gmail.com>
	<20090714152012.GY31378@wasteland.homelinux.net>
Message-ID: <2d56febf0907140854s52d20904y90c7ccb6a0262cb9@mail.gmail.com>

I see. Thanks!

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Tue, Jul 14, 2009 at 11:20 PM, Jochen Schulz <ml at well-adjusted.de> wrote:

> Xavier Ho:
> >
> > Why doesn't the second output print [1, 2, 3, .... , 7, 8, 9] ?
> -- snip
> > print a.n.extend([6, 7, 8, 9])
>
> extend doesn't fail. It just returns None and extends the list in place.
>
> In [1]: l = [1, 2, 3]
>
> In [2]: l.extend([4, 5, 6])
>
> In [3]: l
> Out[3]: [1, 2, 3, 4, 5, 6]
>
>
> J.
> --
> When I get home from the supermarket I don't know what to do with all the
> plastic.
> [Agree]   [Disagree]
>                 <http://www.slowlydownward.com/NODATA/data_enter2.html>
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.9 (GNU/Linux)
>
> iEYEARECAAYFAkpcoiwACgkQ+AfZydWK2zmchgCfZjRCOGTa0OZ1Q045sCLZfpvD
> EIEAnjJ8/uNwPYFfCsGNbQIDd5+LnkbA
> =fCdV
> -----END PGP SIGNATURE-----
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/cc25e4ed/attachment-0001.html>

From python at mrabarnett.plus.com  Tue Jul 14 11:55:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 16:55:18 +0100
Subject: Proposal: Decimal literals in Python.
In-Reply-To: <WN-dnXhGXtWYO8HXnZ2dnUVZ_j-dnZ2d@pdx.net>
References: <4721ab28$0$1238$e4fe514c@dreader28.news.xs4all.nl>	<1193438763.190428.134710@q5g2000prf.googlegroups.com>	<87tzodii6i.fsf@benfinney.id.au>	<1193494184.618613.81090@50g2000hsm.googlegroups.com>	<n46ai3t0biv5390r4ijhq6ddn9va47f197@4ax.com>
	<WN-dnXhGXtWYO8HXnZ2dnUVZ_j-dnZ2d@pdx.net>
Message-ID: <4A5CAA66.3080608@mrabarnett.plus.com>

Scott David Daniels wrote:
> Tim Roberts wrote:
>> My favorite notation for this comes from Ada, which allows arbitrary 
>> bases
>> from 2 to 16, and allows for underscores within numeric literals:
>>
>>   x23_bin : constant :=  2#0001_0111#;
>>   x23_oct : constant :=  8#27#;
>>   x23_dec : constant := 10#23#;
>>   x23_hex : constant := 16#17#;
> And mine is one w/o the base 10 bias:
>     .f.123 == 0x123
>     .7.123 == 0o123
>     .1.1101 == 0b1101
> That is, .<largest allowed digit>.<digits>
> -- show the base by showing base-1 in the base.
> I actually built this into "OZ," an interpretter.
> 
Smalltalk uses "r" (for "radix"). If we also permit underscores:

     x23_bin =  2r0001_0111
     x23_oct =  8r27
     x23_dec = 10r23
     x23_hex = 16r17


From doctoresam at gmail.com  Tue Jul 14 11:55:36 2009
From: doctoresam at gmail.com (Deep_Feelings)
Date: Tue, 14 Jul 2009 08:55:36 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
Message-ID: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>

So you have chosen programming language "x" so shall you tell us why
you did so , and  what negatives or positives it has ?


From aahz at pythoncraft.com  Tue Jul 14 11:58:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 08:58:30 -0700
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <h3bogf$oo0$1@panix3.panix.com>
	<h3f5dt$dld$3@lust.ihug.co.nz> <m24otg3hkk.fsf@cs.uu.nl>
Message-ID: <h3i9v6$c5t$1@panix3.panix.com>

In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>> Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand> (LD) wrote:
>
>>LD> In message <h3bogf$oo0$1 at panix3.panix.com>, Aahz wrote:
>
>>Aahz> class AttrDict:
>>Aahz>     def __getitem__(self, key):
>>Aahz>         return getattr(self, key)
>
>>LD> OK, let's try it:
>
>>LD> >>> c = {}
>>LD> >>> c["x"] = 3
>>LD> >>> c.x = 4   
>>LD>     Traceback (most recent call last):
>>LD>       File "<stdin>", line 1, in <module>
>>LD>     AttributeError: 'dict' object has no attribute 'x'
>>LD> >>> class AttrDict:
>>LD>     ...     def __getitem__(self, key):
>>LD>     ...         return getattr(self, key)
>>LD>     ...
>>LD> >>> c.x = 4
>>LD>     Traceback (most recent call last):
>>LD>       File "<stdin>", line 1, in <module>
>>LD>     AttributeError: 'dict' object has no attribute 'x'
>
>>LD> Nope, still doesn't work...
>
>Of course you need c = AttrDict()

Absolutely -- Lawrence really needs to learn to do his own debugging.

>And to get c.x = 4 working you also need a __setitem__. 

Nope.  You do need __setitem__ so that this works:

c['x'] = 4

>And to get c["x"] working AtrrDict should subclass dict:

Definitely not.  There's a perfectly good dict inside a regular class
instance already.  The only reason to subclass from dict is so that you
get all the dict methods for free; however, the cost is that you get
ugly bugs because of e.g.

c['update'] = 'foo'

Overally, I think it's much better/safer to explicitly pull the dict
methods you want to use.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From jfrancis4970 at mailinator.com  Tue Jul 14 11:58:44 2009
From: jfrancis4970 at mailinator.com (jfrancis4970 at mailinator.com)
Date: Tue, 14 Jul 2009 08:58:44 -0700 (PDT)
Subject: how to determine if python is run interactively? (-i)
Message-ID: <17280e94-6c15-4225-9d28-3dff4e0b61a5@p15g2000vbl.googlegroups.com>

how do you determine, from within a python program, whether the python
interpreter was launched in interactive mode? in other words, if i
have a program called "test.py", i want to ensure that the program was
launched with this command line:

python -i test.py

(and not just with "python test.py"). the reason is that i'm doing
some very expensive and lengthy initialization in my test.py program
that will be useless unless the program exits to the python prompt
when it is done, where the user can run further python commands.

obviously i can't use sys.argv since that is only for parameters
passed to the test.py program, not for parameters passed to the python
interpreter itself. i haven't found a way to access these options...

any help would be greatly appreciated!


From pavlovevidence at gmail.com  Tue Jul 14 12:01:37 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 09:01:37 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<h3hrb9$9c$2@lust.ihug.co.nz>
Message-ID: <7d161f1f-2c09-42ca-9bbd-b99a777044ea@j21g2000vbn.googlegroups.com>

On Jul 14, 4:48?am, Lawrence D'Oliveiro <l... at geek-
central.gen.new_zealand> wrote:
> In message <93f6a517-63d8-4c80-
>
> bf19-4614b7099... at m7g2000prd.googlegroups.com>, Carl Banks wrote:
> > Or would you rather let all unexpected exceptions print to standard
> > error, which is often a black hole in non-interactive sitations?
>
> Since when?
>
> Cron, for example, collects standard error and mails it to you.

1. Cron is only one way to run programs non-interactively. (Would that
work with, say, Windows services?)
2. Many systems don't run MTAs these days
3. In my experience the pipeline from cron to mail delivery is error
prone, mainly due to the complexity of configuring MTAs
4. Even if all this works, you might just want to do your logging
directly in Python anyway


Carl Banks


From rylesny at gmail.com  Tue Jul 14 12:12:01 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 14 Jul 2009 09:12:01 -0700 (PDT)
Subject: how to set timeout while colling a soap method?
References: <mailman.3051.1247490480.8015.python-list@python.org>
Message-ID: <e26bf425-f06a-49c3-8ad2-e52e82f3b080@r34g2000vba.googlegroups.com>

On Jul 13, 9:07?am, dzizes <dzizes... at gmail.com> wrote:
> Hello!
>
> I wrote some some python code for executing a soap method:
>
> import SOAPpy
> from SOAPpy import WSDL
>
> _server = WSDL.Proxy(some wsdl)
> r=_server.generuj(some parameters...)
> print r.encode('cp1250')
>
> It works fine. However, the execution time of this soap method might be
> long. Therefore, I would like to set a timeout like 1 minute, after which I
> would post a timeoute message.
>
> Any ideas?
> Greats,
>
> --
> View this message in context:http://www.nabble.com/how-to-set-timeout-while-colling-a-soap-method-...
> Sent from the Python - python-list mailing list archive at Nabble.com.

I don't believe SOAPpy supports this directly. You can set the timeout
globally before you make your SOAP call:

import socket
socket.setdefaulttimeout(60)

http://docs.python.org/library/socket.html#socket.setdefaulttimeout


From python at mrabarnett.plus.com  Tue Jul 14 12:14:03 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 17:14:03 +0100
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <4A5CAECB.8080604@mrabarnett.plus.com>

Deep_Feelings wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and  what negatives or positives it has ?

I've heard of "C" and "D", but not "x", unless you mean XPL (X
Programming Language) or PLAN-X. :-)


From duncan.booth at invalid.invalid  Tue Jul 14 12:26:28 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 14 Jul 2009 16:26:28 GMT
Subject: how to determine if python is run interactively? (-i)
References: <17280e94-6c15-4225-9d28-3dff4e0b61a5@p15g2000vbl.googlegroups.com>
Message-ID: <Xns9C48B169DC8C2duncanbooth@127.0.0.1>

jfrancis4970 at mailinator.com wrote:

> how do you determine, from within a python program, whether the python
> interpreter was launched in interactive mode?

sys.flags.interactive or sys.flags.inspect



From duncan.booth at invalid.invalid  Tue Jul 14 13:10:17 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 14 Jul 2009 17:10:17 GMT
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<mailman.3088.1247577307.8015.python-list@python.org>
Message-ID: <Xns9C48B8D5619D0duncanbooth@127.0.0.1>

John Machin <sjmachin at lexicon.net> wrote:

> Try an iterative version of checking that () [] and {}
> are balanced and nested appropriately.

Here's how I might approach the more general case:

def balanced(s, parens=("()",)):
    '''
    Example:
    >>> balanced('aAAA(b[bb(c]c))')
    True
    >>> balanced('aAAA(b[bb(c]c))', parens=("()", "[]"))
    False
    '''
    s = re.sub("[^%s]+" % re.escape("".join(parens)), "", s)
    for i in range(len(s)/2):
        for p in parens:
            s = s.replace(p, "")
    return not s

For short strings this is obviously slower than your 'iterative' function, 
but the run time mostly depends on the number of pairs of parentheses 
rather than the total length of the string, so for example it starts 
winning on a string with 2 pairs of parentheses about 75 characters long.


From amrita at iisermohali.ac.in  Tue Jul 14 13:33:59 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Tue, 14 Jul 2009 23:03:59 +0530 (IST)
Subject: select lines in python
Message-ID: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>

Dear all,

Can anyone tell me that suppose i have a file having content like:

    _Atom_name
      _Atom_type
      _Chem_shift_value
      _Chem_shift_value_error
      _Chem_shift_ambiguity_code
     1     1   PHE       H     H      8.49     0.02     1
     2     1   PHE       HA    H      4.60     0.02     1
     3     1   PHE       CA    C     57.83      0.3     1
     4     2   LEU       H     H      8.23     0.02     1
     5     2   LEU       HA    H      4.25     0.02     1
     6     2   LEU       HB2   H      1.54     0.02     1
     7     3   ASP       H     H      8.10     0.02     1
     8     3   ASP       HA    H      4.52     0.02     1
     9     3   ASP       HB2   H      2.65     0.02     1
stop


now what i want that instead of copying all the lines it will just write
the information about PHE and ASP then how i acn do that using python
programming.Kindly tell me the command for that.

Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From degibb at gmail.com  Tue Jul 14 13:48:06 2009
From: degibb at gmail.com (David Gibb)
Date: Tue, 14 Jul 2009 13:48:06 -0400
Subject: select lines in python
In-Reply-To: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
References: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
Message-ID: <ef49cad40907141048v6b0ee769jf250cf8aede8f860@mail.gmail.com>

try something like:

for line in open("filename").readlines():
    if (re.search("PHE|ASP",line):
        print line

On Tue, Jul 14, 2009 at 1:33 PM, <amrita at iisermohali.ac.in> wrote:
> Dear all,
>
> Can anyone tell me that suppose i have a file having content like:
>
> ? ?_Atom_name
> ? ? ?_Atom_type
> ? ? ?_Chem_shift_value
> ? ? ?_Chem_shift_value_error
> ? ? ?_Chem_shift_ambiguity_code
> ? ? 1 ? ? 1 ? PHE ? ? ? H ? ? H ? ? ?8.49 ? ? 0.02 ? ? 1
> ? ? 2 ? ? 1 ? PHE ? ? ? HA ? ?H ? ? ?4.60 ? ? 0.02 ? ? 1
> ? ? 3 ? ? 1 ? PHE ? ? ? CA ? ?C ? ? 57.83 ? ? ?0.3 ? ? 1
> ? ? 4 ? ? 2 ? LEU ? ? ? H ? ? H ? ? ?8.23 ? ? 0.02 ? ? 1
> ? ? 5 ? ? 2 ? LEU ? ? ? HA ? ?H ? ? ?4.25 ? ? 0.02 ? ? 1
> ? ? 6 ? ? 2 ? LEU ? ? ? HB2 ? H ? ? ?1.54 ? ? 0.02 ? ? 1
> ? ? 7 ? ? 3 ? ASP ? ? ? H ? ? H ? ? ?8.10 ? ? 0.02 ? ? 1
> ? ? 8 ? ? 3 ? ASP ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
> ? ? 9 ? ? 3 ? ASP ? ? ? HB2 ? H ? ? ?2.65 ? ? 0.02 ? ? 1
> stop
>
>
> now what i want that instead of copying all the lines it will just write
> the information about PHE and ASP then how i acn do that using python
> programming.Kindly tell me the command for that.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From phonky at europe.com  Tue Jul 14 13:50:54 2009
From: phonky at europe.com (phonky)
Date: Tue, 14 Jul 2009 19:50:54 +0200
Subject: one-time factory in python for an experienced java guy
In-Reply-To: <f83064a1-49bd-4133-980c-ab847a0b3bdf@n30g2000vba.googlegroups.com>
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
	<f83064a1-49bd-4133-980c-ab847a0b3bdf@n30g2000vba.googlegroups.com>
Message-ID: <cc950$4a5cc57e$d9a2f023$7401@news.hispeed.ch>

Thanks for all replies.

I need to practice much more pythonese....
In fact I don't think to understand all
of your suggestions, so I'll need to
go through them and decide what approach I am going
to take.

Thanks a lot!


From mensanator at aol.com  Tue Jul 14 13:52:39 2009
From: mensanator at aol.com (Mensanator)
Date: Tue, 14 Jul 2009 10:52:39 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com>

On Jul 14, 10:55?am, Deep_Feelings <doctore... at gmail.com> wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and ?what negatives or positives it has ?

language must have

- unlimited precision integers
- easy to program
- IDE not required
- reasonable speed
- math library needs to include number theoretic functions
  like GCD, LCM, Modular Inverse, etc.
- not fucking retarded like F#

That leaves Python (along with gympy, the Python wrapper for
the GMP library, which could be used with C or C++ if it weren't
for the ease of use issue) as the obvious choice.

As for negatives, the GMP library doesn't factor.

As for positives, you can call a factoring program from Python
and capture the output (and have it correct the bug in the factoring
program without having to fix the factoring program).


From tonylay at gmail.com  Tue Jul 14 13:59:24 2009
From: tonylay at gmail.com (Tony Lay)
Date: Tue, 14 Jul 2009 10:59:24 -0700 (PDT)
Subject: ImportError: No module named _functools
Message-ID: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>

I'm sooo close to getting this meld program running....had to install
a lot of things in /usr/local to get to pygtk2 functional and I'm
trying to run the meld program and get...

RHEL4 server


Traceback (most recent call last):
  File "/usr/local/bin/meld", line 35, in <module>
    import gettext
  File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
    import locale, copy, os, re, struct, sys
  File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
    import functools
  File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
    from _functools import partial, reduce
ImportError: No module named _functools

This is with me building all of the dependencies as well as python
with
./configure --prefix=/usr/local --exec-prefix=/usr/local
make distclean
make
make -i install
ldconfig

export PYTHONHOME=/usr/local/lib/python2.6
export PYTHONPATH=/usr/local/lib/python2.6:/usr/local/lib/python2.6/
site-packages

I thought it might have been an err of the application, but I ran
python and received the same error:
[root at orlstscts1 meld-1.0.0]# python
Python 2.6.2 (r262:71600, Jul 14 2009, 11:47:04)
[GCC 3.4.6 20060404 (Red Hat 3.4.6-9)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import functools
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
    from _functools import partial, reduce
ImportError: No module named _functools

Kind of a python n00b, but the functools.py is there, it's in the
path...everything seems to be lined up right.

Problem is that the server this is on is stable (read older), and I am
to not touch the older software unless it's as a last resort.  For
this reason everything is in /usr/local and built from the ground up.

I'm hoping that there's some silly dependency I'm missing.  I've
installed the following:
atk-1.26.0
pkg-config-0.23
cairo-1.8.8
libglade-2.6.4
pycairo-1.8.6
fontconfig-2.7.0
libpng-1.2.37
pygobject-2.18.0
freetype-2.1.10
libxml2-2.7.3
pygtk-2.15.2
gettext-0.17
meld-1.0.0
pygtk-2.8.6
glade3-3.6.7
meld-1.1.5
Python-2.6.2
glib-2.20.4
glibc-2.9
meld-1.3.0 (no install)
tcl8.5.7
tk8.5.7
gtk+-2.16.4
pango-1.20.5
intltool-0.35.5
pixman-0.15.14

Took me a while to get by fontconfig/freetype junk because (usr/local/
lib/libfontconfig.so: undefined reference to `FT_Select_Size') but
that's a little OT.

If there are any recommendations of what to attack or further
information would help let me know!

Regards,

-Tony


From weafon at lbl.gov  Tue Jul 14 14:03:22 2009
From: weafon at lbl.gov (weafon)
Date: Tue, 14 Jul 2009 11:03:22 -0700
Subject: How to keep a function as a generator function when the yield operator
	is moved into its sub-functions??
Message-ID: <4A5CC86A.9070907@lbl.gov>

Hi guys,

I have a question about the usage of yield. As shown in the below 
example, in general, if there is a code segment commonly used by two or 
more functions, we may isolate the segment into a function and then call 
it from other functions if necessary.

def func1():
    ....
    while(cond):
        .....
        commoncode()
        ...


def func2():
    ....
    while(cond):
        .....
        commoncode()
        ...

def commoncode()
    AAAA
    BBBB
    CCCC

However, if there is a 'yield' operation in the common code segment, the 
isolation causes that func1 and func2 become a non-generator function!! 
Although I can prevent such an isolation by just duplicating the segment 
in func1 and func2 to keep both of them being generator functions, the 
code may become ugly and hard to maintain particularly when coomoncode() 
is long.

The problem may be resolved if I can define the commoncode() as an 
inline function or marco. Unfortunately, inline and marco do not seems 
to be implemented in python. Thus, how can I isolate a common segment 
into a function when there are yield operations in the common segment?

Thanks,
Weafon







From nagle at animats.com  Tue Jul 14 14:06:17 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 14 Jul 2009 11:06:17 -0700
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
Message-ID: <4a5cc8c0$0$1655$742ec2ed@news.sonic.net>

walterbyrd wrote:
> I believe Guido himself has said that all indentions should be four
> spaces - no tabs.
> 
> Since backward compatibility is being thrown away anyway, why not
> enforce the four space rule?
> 
> At least that way, when I get python code from somebody else, I would
> know what I am looking at, without having to do a hex dump, or
> something.

    Python 3 enforces the rule that you can't mix tabs and spaces
for indentation in the same file.  That (finally) guarantees that
the indentation you see is what the Python parser sees.  That's
enough to prevent non-visible indentation errors.

    It also means that the Python parser no longer has to have
any concept of how many spaces equal a tab.  So the problem
is now essentially solved.

					John Nagle


From rhodri at wildebst.demon.co.uk  Tue Jul 14 14:21:47 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 14 Jul 2009 19:21:47 +0100
Subject: select lines in python
In-Reply-To: <ef49cad40907141048v6b0ee769jf250cf8aede8f860@mail.gmail.com>
References: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
	<ef49cad40907141048v6b0ee769jf250cf8aede8f860@mail.gmail.com>
Message-ID: <op.uw2lalj8a8ncjz@gnudebst>

On Tue, 14 Jul 2009 18:48:06 +0100, David Gibb <degibb at gmail.com> wrote:

[Something top-posted, which I've shuffled down]

> On Tue, Jul 14, 2009 at 1:33 PM, <amrita at iisermohali.ac.in> wrote:
>> Dear all,
>>
>> Can anyone tell me that suppose i have a file having content like:
>>
>> ? ?_Atom_name
>> ? ? ?_Atom_type
>> ? ? ?_Chem_shift_value
>> ? ? ?_Chem_shift_value_error
>> ? ? ?_Chem_shift_ambiguity_code
>> ? ? 1 ? ? 1 ? PHE ? ? ? H ? ? H ? ? ?8.49 ? ? 0.02 ? ? 1
>> ? ? 2 ? ? 1 ? PHE ? ? ? HA ? ?H ? ? ?4.60 ? ? 0.02 ? ? 1
>> ? ? 3 ? ? 1 ? PHE ? ? ? CA ? ?C ? ? 57.83 ? ? ?0.3 ? ? 1
>> ? ? 4 ? ? 2 ? LEU ? ? ? H ? ? H ? ? ?8.23 ? ? 0.02 ? ? 1
>> ? ? 5 ? ? 2 ? LEU ? ? ? HA ? ?H ? ? ?4.25 ? ? 0.02 ? ? 1
>> ? ? 6 ? ? 2 ? LEU ? ? ? HB2 ? H ? ? ?1.54 ? ? 0.02 ? ? 1
>> ? ? 7 ? ? 3 ? ASP ? ? ? H ? ? H ? ? ?8.10 ? ? 0.02 ? ? 1
>> ? ? 8 ? ? 3 ? ASP ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
>> ? ? 9 ? ? 3 ? ASP ? ? ? HB2 ? H ? ? ?2.65 ? ? 0.02 ? ? 1
>> stop
>>
>>
>> now what i want that instead of copying all the lines it will just write
>> the information about PHE and ASP then how i acn do that using python
>> programming.Kindly tell me the command for that.

> try something like:
>
> for line in open("filename").readlines():
>     if (re.search("PHE|ASP",line):
>         print line
>

The readlines() is unnecessary, and if your file is at all long you'd
be better off precompiling the regular expression.

import re

expr = re.compile("PHE|ASP")
with open("filename") as f:
     for line in f:
         if expr.search(line):
             print line

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From milesck at umich.edu  Tue Jul 14 14:24:06 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Tue, 14 Jul 2009 14:24:06 -0400
Subject: How to keep a function as a generator function when the yield
	operator is moved into its sub-functions??
In-Reply-To: <4A5CC86A.9070907@lbl.gov>
References: <4A5CC86A.9070907@lbl.gov>
Message-ID: <388B397B-40B2-4A4E-857E-49C842708F7F@umich.edu>

On Jul 14, 2009, at 2:03 PM, weafon wrote:

> Hi guys,
>
> I have a question about the usage of yield. As shown in the below  
> example, in general, if there is a code segment commonly used by two  
> or more functions, we may isolate the segment into a function and  
> then call it from other functions if necessary.
>
> def func1():
>   ....
>   while(cond):
>       .....
>       commoncode()
>       ...
>
>
> def func2():
>   ....
>   while(cond):
>       .....
>       commoncode()
>       ...
>
> def commoncode()
>   AAAA
>   BBBB
>   CCCC
>
> However, if there is a 'yield' operation in the common code segment,  
> the isolation causes that func1 and func2 become a non-generator  
> function!! Although I can prevent such an isolation by just  
> duplicating the segment in func1 and func2 to keep both of them  
> being generator functions, the code may become ugly and hard to  
> maintain particularly when coomoncode() is long.
>
> The problem may be resolved if I can define the commoncode() as an  
> inline function or marco. Unfortunately, inline and marco do not  
> seems to be implemented in python. Thus, how can I isolate a common  
> segment into a function when there are yield operations in the  
> common segment?

def func1():
     ...
     while cond:
         ...
         for x in commoncode():
             yield x
         ...

See also:
  - PEP 380: http://www.python.org/dev/peps/pep-0380/
  - Stackless: http://www.stackless.com/

-Miles



From pfeldman at verizon.net  Tue Jul 14 14:25:08 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Tue, 14 Jul 2009 11:25:08 -0700 (PDT)
Subject: missing 'xor' Boolean operator
Message-ID: <24485116.post@talk.nabble.com>


Current Boolean operators are 'and', 'or', and 'not'.  It would be nice to
have an 'xor' operator as well.
-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24485116.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From stefan_ml at behnel.de  Tue Jul 14 14:26:30 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Tue, 14 Jul 2009 20:26:30 +0200
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>

Deep_Feelings wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and  what negatives or positives it has ?

Java, pays a living.

*duck*

Stefan


From http  Tue Jul 14 14:47:08 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 11:47:08 -0700
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com>
Message-ID: <7xab37t843.fsf@ruckus.brouhaha.com>

Mensanator <mensanator at aol.com> writes:
> - unlimited precision integers
> - easy to program
> - IDE not required
> - reasonable speed
> - math library needs to include number theoretic functions
>   like GCD, LCM, Modular Inverse, etc.
> - not fucking retarded like F#

Have you looked at Haskell?

> As for negatives, the GMP library doesn't factor.

Maybe with some MIRACL bindings...


From dickinsm at gmail.com  Tue Jul 14 14:47:41 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 14 Jul 2009 11:47:41 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
Message-ID: <057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>

On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
> have an 'xor' operator as well.

Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
that it's sufficiently useful to justify adding a new keyword 'xor' to
the language;  I suspect that would be an uphill struggle. :)

I'll just note that:

(1) It's easy to emulate xor:  'x xor y' <-> bool(x) != bool(y)

(2) 'and' and 'or' are special in that they have useful short-
circuiting behaviour; xor doesn't have this property (that is, you
always need to evaluate *both* operands to determine the result).

I'd also guess that 'xor' would be much less used than 'and' or 'or',
but maybe that's just a reflection of the sort of code that I tend to
write.

--
Mark


From amrita at iisermohali.ac.in  Tue Jul 14 15:10:32 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Wed, 15 Jul 2009 00:40:32 +0530 (IST)
Subject: select lines in python
Message-ID: <29449.210.212.36.65.1247598632.squirrel@www.iisermohali.ac.in>

Can i become more precise like instead of printing all lines for PHE and
ASP is it possible that for PHE python will print only those lines which
will have information about H and HA and for ASP it will print those lines
which will have information about HA and HB.

Thanks


> On Tue, 14 Jul 2009 18:48:06 +0100, David Gibb <degibb at gmail.com> wrote:
>
> [Something top-posted, which I've shuffled down]
>
>> On Tue, Jul 14, 2009 at 1:33 PM, <amrita at iisermohali.ac.in> wrote:
>>> Dear all,
>>>
>>> Can anyone tell me that suppose i have a file having content like:
>>>
>>> ?? ??_Atom_name
>>> ?? ?? ??_Atom_type
>>> ?? ?? ??_Chem_shift_value
>>> ?? ?? ??_Chem_shift_value_error
>>> ?? ?? ??_Chem_shift_ambiguity_code
>>> ?? ?? 1 ?? ?? 1 ?? PHE ?? ?? ?? H ?? ?? H ?? ?? ??8.49 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 2 ?? ?? 1 ?? PHE ?? ?? ?? HA ?? ??H ?? ?? ??4.60 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 3 ?? ?? 1 ?? PHE ?? ?? ?? CA ?? ??C ?? ?? 57.83 ?? ?? ??0.3 ?? ??
>>> 1
>>> ?? ?? 4 ?? ?? 2 ?? LEU ?? ?? ?? H ?? ?? H ?? ?? ??8.23 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 5 ?? ?? 2 ?? LEU ?? ?? ?? HA ?? ??H ?? ?? ??4.25 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 6 ?? ?? 2 ?? LEU ?? ?? ?? HB2 ?? H ?? ?? ??1.54 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 7 ?? ?? 3 ?? ASP ?? ?? ?? H ?? ?? H ?? ?? ??8.10 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 8 ?? ?? 3 ?? ASP ?? ?? ?? HA ?? ??H ?? ?? ??4.52 ?? ?? 0.02 ?? ??
>>> 1
>>> ?? ?? 9 ?? ?? 3 ?? ASP ?? ?? ?? HB2 ?? H ?? ?? ??2.65 ?? ?? 0.02 ?? ??
>>> 1
>>> stop
>>>
>>>
>>> now what i want that instead of copying all the lines it will just
>>> write
>>> the information about PHE and ASP then how i acn do that using python
>>> programming.Kindly tell me the command for that.
>
>> try something like:
>>
>> for line in open("filename").readlines():
>>     if (re.search("PHE|ASP",line):
>>         print line
>>
>
> The readlines() is unnecessary, and if your file is at all long you'd
> be better off precompiling the regular expression.
>
> import re
>
> expr = re.compile("PHE|ASP")
> with open("filename") as f:
>      for line in f:
>          if expr.search(line):
>              print line
>
> --
> Rhodri James *-* Wildebeest Herder to the Masses
> --
> http://mail.python.org/mailman/listinfo/python-list
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From invalid at invalid  Tue Jul 14 15:12:53 2009
From: invalid at invalid (Grant Edwards)
Date: Tue, 14 Jul 2009 14:12:53 -0500
Subject: select lines in python
References: <mailman.3106.1247598636.8015.python-list@python.org>
Message-ID: <V9OdnccUnuAoRcHXnZ2dnUVZ_qednZ2d@posted.visi>

On 2009-07-14, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:

> Can i become more precise like instead of printing all lines
> for PHE and ASP is it possible that for PHE python will print
> only those lines which will have information about H and HA
> and for ASP it will print those lines which will have
> information about HA and HB?

Yes.

-- 
Grant Edwards                   grante             Yow! I KAISER ROLL?!
                                  at               What good is a Kaiser Roll
                               visi.com            without a little COLE SLAW
                                                   on the SIDE?


From knny.myer at gmail.com  Tue Jul 14 15:15:57 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 12:15:57 -0700 (PDT)
Subject: http://tinypic.com/view.php?pic=m78cgp&s=3
Message-ID: <ddf09334-ab38-4ec1-8186-b8a169f76cbf@q11g2000yqi.googlegroups.com>

Hi,

I'm experiencing a strange behaviour of the Python prompt when using
the
four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
getting
the previous and next command respectively I get ugly characters. See
it
yourself:
http://tinypic.com/view.php?pic=m78cgp&s=3

This is not directly Python-specific, but you feel quite handicapped
if
you must rewrite each command again... so my obvious question is:

How can I fix this? Please, let me know if you can tell me something.

Additional information:
I'm running Ubuntu Linux
I've tried the python prompt in several shell environments and got the
same issue in csh, dash... all negative.

Cheers,
Kenny


From knny.myer at gmail.com  Tue Jul 14 15:20:11 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 12:20:11 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
Message-ID: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>

Hi,

I'm experiencing a strange behaviour of the Python prompt when using
the
four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
getting
the previous and next command respectively I get ugly characters. See
it
yourself:
http://tinypic.com/view.php?pic=m78cgp&s=3

This is not directly Python-specific, but you feel quite handicapped
if
you must rewrite each command again... so my obvious question is:

How can I fix this? Please, let me know if you can tell me something.

Additional information:
I'm running Ubuntu Linux
I've tried the python prompt in several shell environments and got the
same issue in csh, dash... all negative.

Cheers,
Kenny


From dickinsm at gmail.com  Tue Jul 14 15:26:19 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 14 Jul 2009 12:26:19 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
References: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>
Message-ID: <722961de-8416-4aff-a1e2-ce0e18c65503@k1g2000yqf.googlegroups.com>

On Jul 14, 8:20?pm, "~km" <knny.m... at gmail.com> wrote:
> I'm experiencing a strange behaviour of the Python prompt when using
> the
> four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
> getting
> the previous and next command respectively I get ugly characters. See
> it
> yourself:http://tinypic.com/view.php?pic=m78cgp&s=3
>
> This is not directly Python-specific, but you feel quite handicapped
> if
> you must rewrite each command again... so my obvious question is:
>
> How can I fix this? Please, let me know if you can tell me something.
>
> Additional information:
> I'm running Ubuntu Linux
> I've tried the python prompt in several shell environments and got the
> same issue in csh, dash... all negative.

Where did your version of Python 2.6 come from?

If you built your copy of Python 2.6 from source, then the problem is
probably that either the readline library is missing, or (much more
likely) the include files for the readline library are missing.  Look
for a package called something like libreadline5-dev or readline-devel
and install it, and then try rebuilding Python.

Mark


From degibb at gmail.com  Tue Jul 14 15:26:29 2009
From: degibb at gmail.com (David Gibb)
Date: Tue, 14 Jul 2009 15:26:29 -0400
Subject: select lines in python
In-Reply-To: <V9OdnccUnuAoRcHXnZ2dnUVZ_qednZ2d@posted.visi>
References: <mailman.3106.1247598636.8015.python-list@python.org>
	<V9OdnccUnuAoRcHXnZ2dnUVZ_qednZ2d@posted.visi>
Message-ID: <ef49cad40907141226t7e15b091o616c26a9c0ddb5a2@mail.gmail.com>

I think what Grant is saying is that you should read the documentation
for the re module.

David

On Tue, Jul 14, 2009 at 3:12 PM, Grant Edwards<invalid at invalid> wrote:
> On 2009-07-14, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:
>
>> Can i become more precise like instead of printing all lines
>> for PHE and ASP is it possible that for PHE python will print
>> only those lines which will have information about H and HA
>> and for ASP it will print those lines which will have
>> information about HA and HB?
>
> Yes.
>
> --
> Grant Edwards ? ? ? ? ? ? ? ? ? grante ? ? ? ? ? ? Yow! I KAISER ROLL?!
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?at ? ? ? ? ? ? ? What good is a Kaiser Roll
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? visi.com ? ? ? ? ? ?without a little COLE SLAW
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? on the SIDE?
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From clp2 at rebertia.com  Tue Jul 14 15:43:42 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 12:43:42 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>

On Tue, Jul 14, 2009 at 11:47 AM, Mark Dickinson<dickinsm at gmail.com> wrote:
> On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
> wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
>> have an 'xor' operator as well.
>
> Hmm. ?I don't think 'nice' is sufficient. ?You'd need to make the case
> that it's sufficiently useful to justify adding a new keyword 'xor' to
> the language; ?I suspect that would be an uphill struggle. :)
>
> I'll just note that:
>
> (1) It's easy to emulate xor: ?'x xor y' <-> bool(x) != bool(y)

Using the xor bitwise operator is also an option:
bool(x) ^ bool(y)

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Tue Jul 14 15:50:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 12:50:13 -0700
Subject: http://tinypic.com/view.php?pic=m78cgp&s=3
In-Reply-To: <ddf09334-ab38-4ec1-8186-b8a169f76cbf@q11g2000yqi.googlegroups.com>
References: <ddf09334-ab38-4ec1-8186-b8a169f76cbf@q11g2000yqi.googlegroups.com>
Message-ID: <50697b2c0907141250k6f44fc8buda78c22a0a1989b@mail.gmail.com>

On Tue, Jul 14, 2009 at 12:15 PM, ~km<knny.myer at gmail.com> wrote:
> Hi,
>
> I'm experiencing a strange behaviour of the Python prompt when using
> the
> four arrow keys ( not the VIM' nor Emacs' ones ;-) ). Instead of
> getting
> the previous and next command respectively I get ugly characters. See
> it
> yourself:
> http://tinypic.com/view.php?pic=m78cgp&s=3
>
> This is not directly Python-specific, but you feel quite handicapped
> if
> you must rewrite each command again... so my obvious question is:
>
> How can I fix this? Please, let me know if you can tell me something.

I would guess that your Python wasn't compiled with GNU readline support.
Do you get an error if you `import readline`?

Cheers,
Chris
-- 
http://blog.rebertia.com


From dickinsm at gmail.com  Tue Jul 14 15:52:34 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 14 Jul 2009 12:52:34 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<mailman.3108.1247600624.8015.python-list@python.org>
Message-ID: <e8e81467-2752-4176-8ad6-f0326a99ac14@i6g2000yqj.googlegroups.com>

On Jul 14, 8:43?pm, Chris Rebert <c... at rebertia.com> wrote:
> On Tue, Jul 14, 2009 at 11:47 AM, Mark Dickinson<dicki... at gmail.com> wrote:
> > (1) It's easy to emulate xor: ?'x xor y' <-> bool(x) != bool(y)
>
> Using the xor bitwise operator is also an option:
> bool(x) ^ bool(y)

Good point.  For some reason I expected bitwise operations on bools to
return ints rather than bools.  Now I know better. :-)

Thanks,

Mark


From pfeldman at verizon.net  Tue Jul 14 15:56:02 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Tue, 14 Jul 2009 12:56:02 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <24486661.post@talk.nabble.com>


!= does do what I want, except that it doesn't indicate to someone reading
the code that the operands are being treated as logicals.  (Readability is
supposed to be one of the major selling points of Python).  But, this is
probably good enough.

Here's a related issue: I would like to see an option for type checking on
operands of logical operators, so that attempting to apply a logical
operator to non-Boolean entities generates a warning message.  With operand
type checking, 'xor' and != would be different.


Mark Dickinson wrote:
> 
> On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
> wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice
>> to
>> have an 'xor' operator as well.
> 
> Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
> that it's sufficiently useful to justify adding a new keyword 'xor' to
> the language;  I suspect that would be an uphill struggle. :)
> 
> I'll just note that:
> 
> (1) It's easy to emulate xor:  'x xor y' <-> bool(x) != bool(y)
> 
> (2) 'and' and 'or' are special in that they have useful short-
> circuiting behaviour; xor doesn't have this property (that is, you
> always need to evaluate *both* operands to determine the result).
> 
> I'd also guess that 'xor' would be much less used than 'and' or 'or',
> but maybe that's just a reflection of the sort of code that I tend to
> write.
> 
> --
> Mark
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24486661.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From jgardner at jonathangardner.net  Tue Jul 14 16:05:48 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Tue, 14 Jul 2009 13:05:48 -0700 (PDT)
Subject: one-time factory in python for an experienced java guy
References: <b2094$4a5c9024$d9a2f023$3278@news.hispeed.ch>
Message-ID: <df69e052-9979-4bf9-abd5-a9ef229681bf@b14g2000yqd.googlegroups.com>

On Jul 14, 7:03?am, phonky <pho... at europe.com> wrote:
>
> Now, I do not know yet how the account number scheme looks like.

Exactly. The data store knows a lot more than the client (your
program) will ever know.

The correct answer is to do nothing. Use your data store to generate
the IDs for you. The implementations discussed here will not generate
unique IDs across invocations, but the data store will persist the
sequence for you appropriately.

The more correct answer is to abstract away the client to your data
store as well. See SQLAlchemy.

If you're writing a data store, you're doing it wrong. See PostgreSQL,
MySQL, or any other data store out there that are perfectly fine for
development and production use.

I like to use UUIDs for the IDs. Others like big ints that are a
sequence. I've seen people use encrypted big ints, basically random
strings that aren't really random. In the end, you only have to change
the code that talks to the data store, and the rest of your program
only cares about the equality of the id.


From clp2 at rebertia.com  Tue Jul 14 16:22:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 13:22:20 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <24486661.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com>
Message-ID: <50697b2c0907141322y3ec27688g4e6bc29d8fc4b7bf@mail.gmail.com>

> Mark Dickinson wrote:
>>
>> On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
>> wrote:
>>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice
>>> to
>>> have an 'xor' operator as well.
>>
>> Hmm. ?I don't think 'nice' is sufficient. ?You'd need to make the case
>> that it's sufficiently useful to justify adding a new keyword 'xor' to
>> the language; ?I suspect that would be an uphill struggle. :)
>>
>> I'll just note that:
>>
>> (1) It's easy to emulate xor: ?'x xor y' <-> bool(x) != bool(y)
>>
>> (2) 'and' and 'or' are special in that they have useful short-
>> circuiting behaviour; xor doesn't have this property (that is, you
>> always need to evaluate *both* operands to determine the result).
>>
>> I'd also guess that 'xor' would be much less used than 'and' or 'or',
>> but maybe that's just a reflection of the sort of code that I tend to
>> write.
On Tue, Jul 14, 2009 at 12:56 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
<snip>
> Here's a related issue: I would like to see an option for type checking on
> operands of logical operators, so that attempting to apply a logical
> operator to non-Boolean entities generates a warning message.  With operand
> type checking, 'xor' and != would be different.

That's probably not gonna happen. Python is dynamically and duck
typed, and has a sweet coercion system (__bool__ or __nonzero__
depending on your version) to coerce non-booleans to booleans in a
sensible and useful way. So, it's not gonna change any time soon.

Some illustrative examples:
>>> #empty containers considered false
>>> bool([] or {} or set() or "")
>>> False
>>> #zero and null considered false
>>> bool(0 or None)
>>> False
>>> #anything else is, by default, true
>>> bool(object())
>>> True

And like I said, a class can override a special method to provide
whatever boolean semantics are desired. It's surprisingly handy.

Cheers,
Chris
-- 
http://blog.rebertia.com


From jgardner at jonathangardner.net  Tue Jul 14 16:24:29 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Tue, 14 Jul 2009 13:24:29 -0700 (PDT)
Subject: explode()
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>
	<mailman.3019.1247363434.8015.python-list@python.org> 
	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>
	<mailman.3074.1247549579.8015.python-list@python.org> 
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
	<oUU6m.7495$cl4.1167@flpi150.ffdc.sbc.com> 
	<hi3p551ikld7d00c3dvs1vhkmnjgg8ffcn@4ax.com>
Message-ID: <681fe49e-7063-47c5-b0c5-d5088ab216c1@g31g2000yqc.googlegroups.com>

On Jul 14, 6:56?am, Fred Atkinson <fatkin... at mishmash.com> wrote:
>
> Agreed, it doesn't. ?But if my hosting provider won't change it, I'm
> stuck with it. ?
>

Nowadays you can find hosts that allow you to run FastCGI scripts in
any language for dirt cheap. (Hostmonster for instance.) If your host
doesn't allow it, it's time to upgrade.

Any hosting service that supports Ruby on Rails supports Python
through the exact same mechanism.


From aahz at pythoncraft.com  Tue Jul 14 16:30:43 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 13:30:43 -0700
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
Message-ID: <h3iptj$ave$1@panix3.panix.com>

In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
Stefan Behnel  <stefan_ml at behnel.de> wrote:
>Deep_Feelings wrote:
>>
>> So you have chosen programming language "x" so shall you tell us why
>> you did so , and  what negatives or positives it has ?
>
>*duck*

Where do you get the duck programming language?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From jakub.piotr.nowak at gmail.com  Tue Jul 14 16:39:28 2009
From: jakub.piotr.nowak at gmail.com (Jakub P. Nowak)
Date: Tue, 14 Jul 2009 13:39:28 -0700 (PDT)
Subject: ANN: RuPy '09 Conference
Message-ID: <b80b3d32-01ee-4786-aa5b-d0815fd45450@n11g2000yqb.googlegroups.com>

RuPy 2009 :: Strongly Dynamic Conference

Poznan, Poland
November 7-8, 2009

:: Call for speakers

RuPy is a conference about dynamically typed programming languages.
Held for the first time in April 2007 it gathered enthusiasts
from Poland and other countries.

The idea behind the conference is to liven up the
community and make these technologies more popular in Europe.

The first conference was a middle-sized one but came out as
a huge success. We believe it was a great experience for both
attendees and speakers.

RuPy 2009 committee is looking for speakers willing to present
a Python, Ruby, Groovy or any other related subject.
If you have an interesting talk in mind go ahead and submit a
talk proposal. The talk proposal should include a talk title,
brief introduction and your short resume/biography.

To our invited speakers we offer free accommodation, full
board and possibility to interact with a very lively IT community.
You are also free to participate in all the extra events -
'Geek party' always turns out great!

You can also support us by linking to our site and informing
all your friends about the event and the possibility to submit
a talk proposal.

Potential speakers should submit an abstract using the following
form:

https://spreadsheets.google.com/viewform?formkey=dEFEYndsQWR2TGFzRFpzcU9IbFlCT2c6MA..

by September 30th, 2009 for consideration.

If you have any special presentation needs, let us know.

For more details check our site:
http://www.rupy.eu

Best regards,
--
Jakub P. Nowak
RuPy Committee


From suruti94 at gmail.com  Tue Jul 14 16:40:38 2009
From: suruti94 at gmail.com (Mohan Parthasarathy)
Date: Tue, 14 Jul 2009 13:40:38 -0700
Subject: Calling functions: Why this complicated ?
Message-ID: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>

Hi,
I am a newbie. I am reading

http://www.network-theory.co.uk/docs/pytut/KeywordArguments.html

Defining a function with "N" arguments and calling them in "M" different
ways. Why does it have to be this complicated ? I like the idea of calling
the function by explicitly naming the arguments, but there are so many other
ways here that is very confusing. Do people really use all these features ?
Perhaps, there is a equivalent book to "Javascript: Good Parts" for Python ?

-thanks
mohan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/6e6d6d13/attachment-0001.html>

From piet at cs.uu.nl  Tue Jul 14 16:45:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 22:45:46 +0200
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<h3hrb9$9c$2@lust.ihug.co.nz>
	<7d161f1f-2c09-42ca-9bbd-b99a777044ea@j21g2000vbn.googlegroups.com>
Message-ID: <m2bpnnyow5.fsf@cs.uu.nl>

>>>>> Carl Banks <pavlovevidence at gmail.com> (CB) wrote:

>CB> On Jul 14, 4:48?am, Lawrence D'Oliveiro <l... at geek-
>central.gen.new_zealand> wrote:
>>> In message <93f6a517-63d8-4c80-
>>> 
>>> bf19-4614b7099... at m7g2000prd.googlegroups.com>, Carl Banks wrote:
>>> > Or would you rather let all unexpected exceptions print to standard
>>> > error, which is often a black hole in non-interactive sitations?
>>> 
>>> Since when?
>>> 
>>> Cron, for example, collects standard error and mails it to you.

>CB> 1. Cron is only one way to run programs non-interactively. (Would that
>CB> work with, say, Windows services?)
>CB> 2. Many systems don't run MTAs these days
>CB> 3. In my experience the pipeline from cron to mail delivery is error
>CB> prone, mainly due to the complexity of configuring MTAs
>CB> 4. Even if all this works, you might just want to do your logging
>CB> directly in Python anyway

Even then, I think the program would get structured better if the FTP
code would only catch FTP-specific errors, including socket errors
(which is what all_errors does) and to catch programming errors etc on
another level, e.g by the mentioned sys.excepthook.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From deets at nospam.web.de  Tue Jul 14 16:59:04 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 14 Jul 2009 22:59:04 +0200
Subject: How to keep a function as a generator function when the yield
	operator   is moved into its sub-functions??
In-Reply-To: <mailman.3102.1247595252.8015.python-list@python.org>
References: <mailman.3102.1247595252.8015.python-list@python.org>
Message-ID: <7c49soF25pgh4U1@mid.uni-berlin.de>

weafon schrieb:
> Hi guys,
> 
> I have a question about the usage of yield. As shown in the below 
> example, in general, if there is a code segment commonly used by two or 
> more functions, we may isolate the segment into a function and then call 
> it from other functions if necessary.
> 
> def func1():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
> 
> 
> def func2():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
> 
> def commoncode()
>    AAAA
>    BBBB
>    CCCC
> 
> However, if there is a 'yield' operation in the common code segment, the 
> isolation causes that func1 and func2 become a non-generator function!! 


No. Not writing them as generators makes them a non-generator-function.

You are way to unspecific with your examples. But if func1 and func2 are 
themselves supposed to be generators, there is nothing preventing you 
from using them as such.

Diez


From robert.kern at gmail.com  Tue Jul 14 16:59:32 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Tue, 14 Jul 2009 15:59:32 -0500
Subject: missing 'xor' Boolean operator
In-Reply-To: <24486661.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com>
Message-ID: <h3irjm$ro$1@ger.gmane.org>

On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
> != does do what I want, except that it doesn't indicate to someone reading
> the code that the operands are being treated as logicals.  (Readability is
> supposed to be one of the major selling points of Python).  But, this is
> probably good enough.

In the words of those greater than myself, "Not every one-liner needs to be in 
the standard library."

def xor(a, b):
     return bool(a) != bool(b)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From piet at cs.uu.nl  Tue Jul 14 16:59:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 14 Jul 2009 22:59:34 +0200
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <h3bogf$oo0$1@panix3.panix.com>
	<h3f5dt$dld$3@lust.ihug.co.nz> <m24otg3hkk.fsf@cs.uu.nl>
	<h3i9v6$c5t$1@panix3.panix.com>
Message-ID: <m27hybyo95.fsf@cs.uu.nl>

>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:

>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>A> <piet at cs.uu.nl> wrote: 

>>> And to get c.x = 4 working you also need a __setitem__. 

>A> Nope.  You do need __setitem__ so that this works:

>A> c['x'] = 4

Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
that was what the OP wanted (I think).
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From db3l.net at gmail.com  Tue Jul 14 17:06:03 2009
From: db3l.net at gmail.com (David Bolen)
Date: Tue, 14 Jul 2009 17:06:03 -0400
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
Message-ID: <m2prc3dlfo.fsf@valheru.db3l.homeip.net>

John Nagle <nagle at animats.com> writes:

>    Python 3 enforces the rule that you can't mix tabs and spaces
> for indentation in the same file.  That (finally) guarantees that
> the indentation you see is what the Python parser sees.  That's
> enough to prevent non-visible indentation errors.

Are you sure?  It seems to restrict them in the same block, but not in
the entire file.  At least I was able to use both space and tab
indented blocks in the same file with Python 3.0 and 3.1.  I suspect
precluding any mixture at all at the file level would be more
intrusive, for example, when trying to combine multiple code sources
in a single file.

Not that this really changes your final point, since the major risk
of a mismatch between the parser vs. visual display is within a single
block.

>    It also means that the Python parser no longer has to have
> any concept of how many spaces equal a tab.  So the problem
> is now essentially solved.

"has to have" being a future possibility at this point, since I'm
fairly sure the 3.x parser does technically still have the concept of
a tab size of 8, though now it can be an internal implementation
detail.

-- David


From ethan at stoneleaf.us  Tue Jul 14 17:38:12 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 14:38:12 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3irjm$ro$1@ger.gmane.org>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>
	<h3irjm$ro$1@ger.gmane.org>
Message-ID: <4A5CFAC4.7020300@stoneleaf.us>

Robert Kern wrote:
> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
> 
>> != does do what I want, except that it doesn't indicate to someone 
>> reading
>> the code that the operands are being treated as logicals.  
>> (Readability is
>> supposed to be one of the major selling points of Python).  But, this is
>> probably good enough.
> 
> 
> In the words of those greater than myself, "Not every one-liner needs to 
> be in the standard library."
> 
> def xor(a, b):
>     return bool(a) != bool(b)
> 

Let's see...

   and returns the last object that is "true"
   or  returns the first object that is "true"

so should xor return the only object that is "true", else False/None?

def xor(a, b)
     if a and b:
         return None
     elif a:
         return a
     elif b:
         return b
     else:
         return None

~Ethan~


From nobody at nowhere.com  Tue Jul 14 17:40:27 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 14 Jul 2009 22:40:27 +0100
Subject: How to check if any item from a list of strings is in a
	big	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>
	<mailman.3073.1247547957.8015.python-list@python.org>
Message-ID: <pan.2009.07.14.21.40.27.578000@nowhere.com>

On Tue, 14 Jul 2009 02:06:04 -0300, Gabriel Genellina wrote:

>> Matt, how many words are you looking for, in how long a string ?
>> Were you able to time any( substr in long_string ) against re.compile
>> ( "|".join( list_items )) ?
> 
> There is a known algorithm to solve specifically this problem  
> (Aho-Corasick), a good implementation should perform better than R.E. (and  
> better than the gen.expr. with the advantage of returning WHICH string  
> matched)

Aho-Corasick has the advantage of being linear in the length of the
patterns, so the setup may be faster than re.compile(). The actual
searching won't necessarily be any faster (assuming optimal
implementations; I don't know how safe that assumption is).



From ken at seehart.com  Tue Jul 14 17:44:51 2009
From: ken at seehart.com (Ken Seehart)
Date: Tue, 14 Jul 2009 14:44:51 -0700
Subject: decorators - would be nice if...
Message-ID: <4A5CFC53.7050902@seehart.com>

Almost every time I use decorators, I find myself wishing I had access
to the local namespace of the context from which the decorator is
executed.  In practice, decorator is being applied to a method, so the
namespace in question would be the dictionary of the class being created.

Similarly, before decorators were around, I often found myself lamenting
the fact that a class is not created until after it's scope is
completed, since this makes certain kinds of metaprogramming more
difficult.  But after digging deeper, I realized why it is the way it
is, so I don't complain about that.

But it would have been a simple thing to add an argument 'locals' to the
decorator specification.  It's somewhat more difficult to add that now
because of compatibility issues, but perhaps there is a way to get the
same effect.

I can work around all of this by making my decorators just store data to
be processed by a metaclass, but that solution is less elegant.  Also,
it has the slight disadvantage of requiring the use of a metaclass which
would otherwise not be necessary.  I prefer to save metaclass
implementation as a last resort for various reasons (e.g. there does not
seem to be a good way to use multiple metaclasses in a class hierarchy,
and more generally you can't stack them on top of each other (you can
only have one metaclass per class)).

Thoughts?

- Ken




From knny.myer at gmail.com  Tue Jul 14 17:47:04 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 14:47:04 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
References: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>
	<722961de-8416-4aff-a1e2-ce0e18c65503@k1g2000yqf.googlegroups.com>
Message-ID: <21a14a9e-2837-4ae1-a55b-c6b3d50c0513@k19g2000yqn.googlegroups.com>

On 14 Jul., 15:26, Mark Dickinson <dicki... at gmail.com> wrote:
> Where did your version of Python 2.6 come from?
>
> If you built your copy of Python 2.6 from source, then the problem is
> probably that either the readline library is missing, or (much more
> likely) the include files for the readline library are missing. ?Look
> for a package called something like libreadline5-dev or readline-devel
> and install it, and then try rebuilding Python.
>
> Mark

Yes, I built it from source and never thought that there might be such
a library. Now I've re-compiled and my problem is solved!

Have many thanks Mark, and Chris Rebert, too, who responded to my
deleted post, which I've received per mail. Sorry for that incidence.

Cheers,
Kenny


From knny.myer at gmail.com  Tue Jul 14 17:47:17 2009
From: knny.myer at gmail.com (~km)
Date: Tue, 14 Jul 2009 14:47:17 -0700 (PDT)
Subject: bad behaviour in interactive Python prompt
References: <0ba40baf-f6fb-4d5f-b2dc-b75cc4e38fb9@f16g2000vbf.googlegroups.com>
	<722961de-8416-4aff-a1e2-ce0e18c65503@k1g2000yqf.googlegroups.com>
Message-ID: <c99583e2-c02d-4cbb-9b81-8de6b77abc61@h18g2000yqj.googlegroups.com>

On 14 Jul., 15:26, Mark Dickinson <dicki... at gmail.com> wrote:
> Where did your version of Python 2.6 come from?
>
> If you built your copy of Python 2.6 from source, then the problem is
> probably that either the readline library is missing, or (much more
> likely) the include files for the readline library are missing. ?Look
> for a package called something like libreadline5-dev or readline-devel
> and install it, and then try rebuilding Python.
>
> Mark

Yes, I built it from source and never thought that there might be such
a library. Now I've re-compiled and my problem is solved!

Have many thanks Mark, and Chris Rebert, too, who responded to my
deleted post, which I've received per mail. Sorry for that incidence.

Cheers,
Kenny


From python at mrabarnett.plus.com  Tue Jul 14 17:58:27 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 14 Jul 2009 22:58:27 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5CFAC4.7020300@stoneleaf.us>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
Message-ID: <4A5CFF83.9070301@mrabarnett.plus.com>

Ethan Furman wrote:
> Robert Kern wrote:
>> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
>>
>>> != does do what I want, except that it doesn't indicate to someone 
>>> reading
>>> the code that the operands are being treated as logicals.  
>>> (Readability is
>>> supposed to be one of the major selling points of Python).  But, this is
>>> probably good enough.
>>
>>
>> In the words of those greater than myself, "Not every one-liner needs 
>> to be in the standard library."
>>
>> def xor(a, b):
>>     return bool(a) != bool(b)
>>
> 
> Let's see...
> 
>   and returns the last object that is "true"
>   or  returns the first object that is "true"
> 
> so should xor return the only object that is "true", else False/None?
> 
> def xor(a, b)
>     if a and b:
>         return None
>     elif a:
>         return a
>     elif b:
>         return b
>     else:
>         return None
> 
How about:

def xor(a, b):
     return not b and a or not a and b


From nobody at nowhere.com  Tue Jul 14 17:58:28 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 14 Jul 2009 22:58:28 +0100
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com>
	<7xab37t843.fsf@ruckus.brouhaha.com>
Message-ID: <pan.2009.07.14.21.58.28.860000@nowhere.com>

On Tue, 14 Jul 2009 11:47:08 -0700, Paul Rubin wrote:

>> - unlimited precision integers
>> - easy to program
>> - IDE not required
>> - reasonable speed
>> - math library needs to include number theoretic functions
>>   like GCD, LCM, Modular Inverse, etc.
>> - not fucking retarded like F#
> 
> Have you looked at Haskell?

Given his comment about F#, I have a suspicion that he might be
dogmatically opposed to functional languages generally.



From deets at nospam.web.de  Tue Jul 14 18:03:03 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 00:03:03 +0200
Subject: decorators - would be nice if...
In-Reply-To: <mailman.3115.1247607911.8015.python-list@python.org>
References: <mailman.3115.1247607911.8015.python-list@python.org>
Message-ID: <7c4dknF253b3tU1@mid.uni-berlin.de>

Ken Seehart schrieb:
> Almost every time I use decorators, I find myself wishing I had access
> to the local namespace of the context from which the decorator is
> executed.  In practice, decorator is being applied to a method, so the
> namespace in question would be the dictionary of the class being created.

You can access the instance.

def decorator(method):
     def _d(self, *args, **kwargs):
         print self.__dict__
         return method(self, *args, **kwargs)

     return _d

class Foo(object):

     @decorator
     def bar(self, a, b):
         print "bar"


f = Foo()

f.bar(1, 2)

So what exactly it is you are missing? The method's locals()?

And could you explain *why* you are missing this?


Diez


From ethan at stoneleaf.us  Tue Jul 14 18:11:40 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 15:11:40 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5CFF83.9070301@mrabarnett.plus.com>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
Message-ID: <4A5D029C.5030700@stoneleaf.us>

MRAB wrote:
> Ethan Furman wrote:
> 
>> Robert Kern wrote:
>>
>>> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
>>>
>>>> != does do what I want, except that it doesn't indicate to someone 
>>>> reading
>>>> the code that the operands are being treated as logicals.  
>>>> (Readability is
>>>> supposed to be one of the major selling points of Python).  But, 
>>>> this is
>>>> probably good enough.
>>>
>>>
>>>
>>> In the words of those greater than myself, "Not every one-liner needs 
>>> to be in the standard library."
>>>
>>> def xor(a, b):
>>>     return bool(a) != bool(b)
>>>
>>
>> Let's see...
>>
>>   and returns the last object that is "true"
>>   or  returns the first object that is "true"
>>
>> so should xor return the only object that is "true", else False/None?
>>
>> def xor(a, b)
>>     if a and b:
>>         return None
>>     elif a:
>>         return a
>>     elif b:
>>         return b
>>     else:
>>         return None
>>
> How about:
> 
> def xor(a, b):
>     return not b and a or not a and b

In [12]: not 1 and 0 or 1 and not 0
Out[12]: True

In [13]: not 0 and 0 or 0 and not 0
Out[13]: 0

In [14]: not 1 and 1 or 1 and not 1
Out[14]: False

In [15]: not [] and [] or [] and not []
Out[15]: []

Doesn't produce consistent objects, sometimes bool, sometimes something 
else.  'Course, it all depends on what you need.

~Ethan~


From pavlovevidence at gmail.com  Tue Jul 14 18:26:06 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 14 Jul 2009 15:26:06 -0700 (PDT)
Subject: decorators - would be nice if...
References: <mailman.3115.1247607911.8015.python-list@python.org>
Message-ID: <ee0e1bbd-d411-40fa-ae0a-44fef9ea86fe@g31g2000yqc.googlegroups.com>

On Jul 14, 2:44?pm, Ken Seehart <k... at seehart.com> wrote:
[snip]
(e.g. there does not
> seem to be a good way to use multiple metaclasses in a class hierarchy,
> and more generally you can't stack them on top of each other (you can
> only have one metaclass per class)).
>
> Thoughts?

If "stacking" metaclasses (whatever that means) is a possible approach
to your problem, you might want to ask yourself if you're trying to be
too clever.

Would you like to give us an example of a decorator you think would
benefit from having access to local namespace?  We might be able to
suggest other possibilities.


Carl Banks


From darkwater42 at gmail.com  Tue Jul 14 18:54:31 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 15:54:31 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<4a5c5e7f$0$30235$9b4e6d93@newsspool1.arcor-online.net>
Message-ID: <d0afeb7e-1120-4fff-b9cc-42ff8a0ced77@h11g2000yqb.googlegroups.com>

On Jul 14, 7:38?am, Florian Brucker <t... at torfbold.com> wrote:

> Douglas Alan wrote:

> > Thank you. My question wasn't intended to be Python specific, though.
> > I am just curious for purely academic reasons about whether there is
> > such an algorithm. All the sources I've skimmed only seem to the
> > answer the question via omission. Which is kind of strange, since it
> > seems to me like an obvious question to ask.

> IIRC comp.programming would be the place to ask such questions.

Thanks, yes that does look like a good place to post such questions.
Unfortunately, it also looks to be overrun with stories on "hot girls
top and bottom sexy movie", though I'm sure I can ignore those. I'm
scared to look at the posting on "tricky bit twiddling", though.

|>ouglas



From aahz at pythoncraft.com  Tue Jul 14 18:58:06 2009
From: aahz at pythoncraft.com (Aahz)
Date: 14 Jul 2009 15:58:06 -0700
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <m24otg3hkk.fsf@cs.uu.nl>
	<h3i9v6$c5t$1@panix3.panix.com> <m27hybyo95.fsf@cs.uu.nl>
Message-ID: <h3j2hu$nmf$1@panix3.panix.com>

In article <m27hybyo95.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>
>>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>>A> <piet at cs.uu.nl> wrote: 
>
>>>> And to get c.x = 4 working you also need a __setitem__. 
>
>>A> Nope.  You do need __setitem__ so that this works:
>
>>A> c['x'] = 4
>
>Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
>that was what the OP wanted (I think).

c.x = 4 
already updates the instance dict, so there's no need to change any class
methods to support it.  That is, IME it's much better to add methods to
a regular class to make it more dict-like using the built-in instance
dict rather than changing any of the attribute mechanisms.  If you're
really curious, I recommend trying several approaches yourself to see
what works better.  ;-)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From Scott.Daniels at Acm.Org  Tue Jul 14 19:00:03 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 16:00:03 -0700
Subject: How to check if any item from a list of strings is in a big
	string?
In-Reply-To: <pan.2009.07.14.21.40.27.578000@nowhere.com>
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com>
	<mailman.3073.1247547957.8015.python-list@python.org>
	<pan.2009.07.14.21.40.27.578000@nowhere.com>
Message-ID: <3cCdna9IneyskcDXnZ2dnUVZ_g6dnZ2d@pdx.net>

Nobody wrote:
> On Tue, 14 Jul 2009 02:06:04 -0300, Gabriel Genellina wrote:
> 
>>> Matt, how many words are you looking for, in how long a string ?
>>> Were you able to time any( substr in long_string ) against re.compile
>>> ( "|".join( list_items )) ?
>> There is a known algorithm to solve specifically this problem  
>> (Aho-Corasick), a good implementation should perform better than R.E. (and  
>> better than the gen.expr. with the advantage of returning WHICH string  
>> matched)
> 
> Aho-Corasick has the advantage of being linear in the length of the
> patterns, so the setup may be faster than re.compile(). The actual
> searching won't necessarily be any faster (assuming optimal
> implementations; I don't know how safe that assumption is).
> 
Having done a fast Aho-Corasick implementation myself, I can assure you
that the actual searching can be incredibly fast.  RE conversion usually
goes to a slightly more general machine than the Aho-Corasick processing
requires.

--Scott David Daniels
Scott.Daniels at Acm.Org



From dstanek at dstanek.com  Tue Jul 14 19:03:02 2009
From: dstanek at dstanek.com (David Stanek)
Date: Tue, 14 Jul 2009 19:03:02 -0400
Subject: How to unbuffer Python's output
In-Reply-To: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
References: <082AEC0F05C496449D86020DBFE466156F7C0BF365@ADSK-NAMSG-02.MGDADSK.autodesk.com>
Message-ID: <de32cc030907141603u6767b6edi7290d42fbd37a644@mail.gmail.com>

2009/7/14 Lily Gao <Lily.Gao at autodesk.com>:
> Hi, All
>
> I am calling a python program in perl and use redirection,
>
> Like :
>
> `python x.py > 1.log 2>&1`

Try tihs instead:
    python x.py 2>&1 > 1.log

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From freyr.magnusson at gmail.com  Tue Jul 14 19:07:09 2009
From: freyr.magnusson at gmail.com (Freyr)
Date: Tue, 14 Jul 2009 16:07:09 -0700 (PDT)
Subject: Passing handlers between bound c++ libs
Message-ID: <3e7b0717-a665-4f42-b7bd-7a99d59258c4@m11g2000yqh.googlegroups.com>

I have a python bound physics library that uses handler to process
events. The passing of handlers between c++ and python causes a huge
overhead slowing down the process.  Can I implement a handler in my
custom python bound c++ lib B and pass it to blackbox python bound c++
lib A so that A would call B directly without passing through the
python layer?  Or to phrase the question differently:  Can I pass a
handler from B through python to A so that A will invoke B with out
calling into python code?


From lists at cheimes.de  Tue Jul 14 19:08:24 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 15 Jul 2009 01:08:24 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
Message-ID: <h3j358$lhr$1@ger.gmane.org>

Chris Rebert wrote:
> Using the xor bitwise operator is also an option:
> bool(x) ^ bool(y)

I prefer something like:

    bool(a) + bool(b) == 1

It works even for multiple tests (super xor):

  if bool(a) + bool(b) + bool(c) + bool(d) != 1:
      raise ValueError("Exactly one of a, b, c and d must be true")

Christian



From darkwater42 at gmail.com  Tue Jul 14 19:08:36 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 16:08:36 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
Message-ID: <95f25380-d71f-41b6-82b8-f991551e8a1a@32g2000yqj.googlegroups.com>

On Jul 14, 8:10?am, Piet van Oostrum <p... at cs.uu.nl> wrote:

> Of course you can take any BST algorithm and replace pointers by indices
> in the array and allocate new elements in the array. But then you need
> array elements to contain the indices for the children explicitely.

And why is this a problem? This is how binary heaps are typically
implemented, and it all works swimmingly. The node rotations for
keeping a binary heap balanced turn out to be suitable for
representation in a flat array. I.e., when you do the node rotations,
you only ever have to copy log n array elements.

In general, however, you can't move nodes around so easily when
represented in a flat array. A node movement in a tree represented
with pointers, might involves changing just two pointers, while when
represented as a flat array, might involve copying most of the array
to maintain the tree invariants. It just so turns out that maintaining
the invariants for a binary heap does not have this issue.

This is why I was curious about treaps, which are a type of binary
heap. The CLRS textbook on algorithms discusses treaps, but doesn't
ever mention whether they are as fortunate as less constrained binary
heaps. I'm sure I could work out for myself whether the treap
rotations are suitable for storage in a flat array, but I might make a
mistake somewhere in my reasoning, and then never know the true
answer!

|>ouglas


From Scott.Daniels at Acm.Org  Tue Jul 14 19:17:35 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 16:17:35 -0700
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <h3iptj$ave$1@panix3.panix.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
	<h3iptj$ave$1@panix3.panix.com>
Message-ID: <AsedncM--I7RjcDXnZ2dnUVZ_rudnZ2d@pdx.net>

Aahz wrote:
> In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
> Stefan Behnel  <stefan_ml at behnel.de> wrote:
>> Deep_Feelings wrote:
>>> So you have chosen programming language "x" so shall you tell us why
>>> you did so , and  what negatives or positives it has ?
>> *duck*
> 
> Where do you get the duck programming language?

It shares a type system with Python, of course.  :-)

--Scott David Daniels
Scott.Daniels at Acm.Org


From jackdied at gmail.com  Tue Jul 14 19:23:31 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Tue, 14 Jul 2009 19:23:31 -0400
Subject: decorators - would be nice if...
In-Reply-To: <4A5CFC53.7050902@seehart.com>
References: <4A5CFC53.7050902@seehart.com>
Message-ID: <b8e622740907141623w21a7ef25tde398964eebfc5a5@mail.gmail.com>

On Tue, Jul 14, 2009 at 5:44 PM, Ken Seehart<ken at seehart.com> wrote:
> Almost every time I use decorators, I find myself wishing I had access
> to the local namespace of the context from which the decorator is
> executed. ?In practice, decorator is being applied to a method, so the
> namespace in question would be the dictionary of the class being created.

As other mentioned, an example would make it clearer what you are trying to do.

> Similarly, before decorators were around, I often found myself lamenting
> the fact that a class is not created until after it's scope is
> completed, since this makes certain kinds of metaprogramming more
> difficult. ?But after digging deeper, I realized why it is the way it
> is, so I don't complain about that.

Py3k to the rescue!  Because the metaclass is defined outside of the
class body it is possible to pass in a metaclass that uses a custom
dictionary.  This was added to make some common cases easier (like
knowing in which order members were defined).  This is not
backportable to 2.6 because the __metaclass__ is defined inside the
class body and possibly anywhere in the class body.

-Jack


From darkwater42 at gmail.com  Tue Jul 14 19:23:58 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 16:23:58 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl> <xcadneiIYYK1GcHXnZ2dnUVZ_qadnZ2d@pdx.net>
Message-ID: <5e8d271a-e3e7-451b-92ca-b5321da9b706@o6g2000yqj.googlegroups.com>

On Jul 14, 9:19?am, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:

> It may well be that there is no good simple solution, and people avoid
> writing about non-existent algorithms.

I can't imagine why that should be the case. The CLRS textbook on
algorithms, for instance, goes to some pains to mathematically prove
that there is no comparison sort that can operate in faster than O(n
log n) time.

And any decent discussion of rabies would be sure to mention that
there is no known cure.

CLRS talks about binary heaps, binary search trees, and treaps, and it
shows how to maintain a binary heap in a flat array efficiently (n log
n time overall), but it never even seems to bring up the subject as to
whether a binary search tree or a treap can also be efficiently
maintained in a flat array.

Though it may be the case that these questions are left as exercises
for the student, and therefore buried in the exercises and problem
sets that I didn't read carefully.

> Piet van Oostrum wrote:

> > Of course you can take any BST algorithm and replace pointers by indices
> > in the array and allocate new elements in the array. But then you need
> > array elements to contain the indices for the children explicitely.

> And you loower your locality of reference (cache-friendliness).
> Note the insert in Python, for example, is quite cache-friendly.

I can't see that a binary search tree would typically have
particularly good cache-friendliness, so I can't see why a flat-array
representation, such as is done for a binary heap, would have
particularly worse cache-reference.

|>ouglas


From clp2 at rebertia.com  Tue Jul 14 19:31:25 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 16:31:25 -0700
Subject: Calling functions: Why this complicated ?
In-Reply-To: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
Message-ID: <50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>

On Tue, Jul 14, 2009 at 1:40 PM, Mohan Parthasarathy<suruti94 at gmail.com> wrote:
> Hi,
> I am a newbie. I am reading
> http://www.network-theory.co.uk/docs/pytut/KeywordArguments.html
> Defining a function with "N" arguments and calling them in "M" different
> ways. Why does it have to be this complicated ? I like the idea of calling
> the function by explicitly naming the arguments, but there are so many other
> ways here that is very confusing. Do people really use all these features ?
> Perhaps, there is a equivalent book to "Javascript: Good Parts" for Python ?

Oh $DEITY, don't even compare Python to JavaScript. At least in
Python, when you try to access a non-existent attribute, a proper
NameError exception is thrown rather than silently getting back
"undefined"... (*has traumatic horror story flashback*)

The calling syntax is not so much complicated as it is liberating.
Are you a C junkie who has never heard of named arguments?
    Just use the call sequence like you've always done.
Are you a exacting Smalltalk or Objective-C person who likes to name
all the arguments all the time for clarity?
    You can do that.
Do you want to call a function with lots of default arguments but only
want to override a couple of them?
    Specifying them by name lets you do that succinctly.
Do you not want to have to worry about the order of the parameters
because it seems kinda arbitrary?
    Then specify the arguments by name.
etc...

And if you try and specify an argument twice, Python will throw an
error, so anything truly confusing will get caught right away.
And there's only one definition syntax, so while the call could be
complicated, figuring out what it means by looking to the definition
is fairly easy.

There really aren't that many ways it's done in practice. In practice,
the following styles cover 90% of cases:
- All named arguments: foo(bar=a, baz=b, qux=c)
- All sequential arguments: foo(a, b, c)
- All sequential arguments, with a few optional arguments given by
name: foo(a, b, c, flag=True, style=qux)
- Simple pass-through: foo(*args, **kwargs)

Granted, there's 4 of them, but each taken by itself seems pretty easy
to read, IMHO.

Cheers,
Chris
-- 
http://blog.rebertia.com


From darkwater42 at gmail.com  Tue Jul 14 19:33:33 2009
From: darkwater42 at gmail.com (Douglas Alan)
Date: Tue, 14 Jul 2009 16:33:33 -0700 (PDT)
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
	<95f25380-d71f-41b6-82b8-f991551e8a1a@32g2000yqj.googlegroups.com>
Message-ID: <01ea9a41-5885-4df3-91ae-24cfa5bfbec4@y17g2000yqn.googlegroups.com>

I wrote:

> On Jul 14, 8:10?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>
> > Of course you can take any BST algorithm and replace pointers by indices
> > in the array and allocate new elements in the array. But then you need
> > array elements to contain the indices for the children explicitely.


> And why is this a problem?

Oh, I'm sorry -- I see what you are saying now. You're saying you can
just implement a normal binary search tree, but store the tree nodes
in an array, as if it were a chunk of memory, and use array indices as
pointers, rather than using memory addresses as pointers.

Fair enough, but I'm not sure what that would buy you. Other than,
perhaps some improved locality of reference, and the potential to
perhaps get the pointers take up less space if you know the array is
never going to grow to be very large.

|>ouglas



From Scott.Daniels at Acm.Org  Tue Jul 14 19:36:35 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 14 Jul 2009 16:36:35 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <mailman.3114.1247607712.8015.python-list@python.org>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>
	<mailman.3114.1247607712.8015.python-list@python.org>
Message-ID: <06edna4zh5xcicDXnZ2dnUVZ_tKdnZ2d@pdx.net>

Ethan Furman wrote:
>   and returns the last object that is "true"
A little suspect this.
_and_ returns the first object that is not "true," or the last object.
>   or  returns the first object that is "true"
Similarly:
_or_ returns the first object that is "true," or the last object.

> so should xor return the only object that is "true", else False/None?

Xor has the problem that in two cases it can return neither of its args.
Not has behavior similar in those cases, and we see it returns False or
True.  The Pythonic solution is therefore to use False.

> def xor(a, b)
>     if a and b:
>         return None
>     elif a:
>         return a
>     elif b:
>         return b
>     else:
>         return None

     def xor(a, b):
         if bool(a) == bool(b):
             return False
         else:
             return a or b

Side-effect counting in applications of bool(x) is ignored here.
If minimizing side-effects is needed:

     def xor(a, b):
         if a:
             if not b:
                 return a
         elif b:
             return b
         return False

--Scott David Daniels
Scott.Daniels at Acm.Org


From ethan at stoneleaf.us  Tue Jul 14 19:48:26 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 16:48:26 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3j358$lhr$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
Message-ID: <4A5D194A.6050301@stoneleaf.us>

Christian Heimes wrote:
> Chris Rebert wrote:
> 
>>Using the xor bitwise operator is also an option:
>>bool(x) ^ bool(y)
> 
> 
> I prefer something like:
> 
>     bool(a) + bool(b) == 1
> 
> It works even for multiple tests (super xor):
> 
>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>       raise ValueError("Exactly one of a, b, c and d must be true")
> 
> Christian
> 

super_xor!  I like it!

In [23]: def super_xor(args, failure=False):
    ....:     found_one = False
    ....:     for item in args:
    ....:         if item:
    ....:             if found_one:
    ....:                 return failure
    ....:             else:
    ....:                 found_one = item
    ....:     return found_one or failure

In [25]: super_xor((0, 1, 0, []))
Out[25]: 1

In [26]: super_xor((0, 1, 0, [],('this',)))
Out[26]: False

In [27]: super_xor((0, {}, 0, [],()))
Out[27]: False

In [16]: def super_or(args, failure=False):
    ....:     for item in args:
    ....:         if item:
    ....:             return item
    ....:     else:
    ....:         return failure
    ....:

In [17]: super_or((None, [], 0, 3, {}))
Out[17]: 3

In [18]: super_or((None, [], 0, (), {}))
Out[18]: False

In [19]: def super_and(args, failure=False):
    ....:     for item in args:
    ....:         if not item:
    ....:             return failure
    ....:     else:
    ....:         return item
    ....:

In [20]: super_and((1, 2, 3))
Out[20]: 3

In [21]: super_and((1, 2, 3, 4))
Out[21]: 4

In [22]: super_and((1, 0, 3, 4))
Out[22]: False

A whole family of supers.  :)

~Ethan~


From ethan at stoneleaf.us  Tue Jul 14 19:53:37 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 14 Jul 2009 16:53:37 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <06edna4zh5xcicDXnZ2dnUVZ_tKdnZ2d@pdx.net>
References: <24485116.post@talk.nabble.com>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<24486661.post@talk.nabble.com>	<h3irjm$ro$1@ger.gmane.org>	<mailman.3114.1247607712.8015.python-list@python.org>
	<06edna4zh5xcicDXnZ2dnUVZ_tKdnZ2d@pdx.net>
Message-ID: <4A5D1A81.5000406@stoneleaf.us>

Scott David Daniels wrote:
> Ethan Furman wrote:
> 
>>   and returns the last object that is "true"
> 
> A little suspect this.
> _and_ returns the first object that is not "true," or the last object.
> 
>>   or  returns the first object that is "true"
> 
> Similarly:
> _or_ returns the first object that is "true," or the last object.
> 

Thanks for the correction.

~Ethan~

> 
> --Scott David Daniels
> Scott.Daniels at Acm.Org



From magawake at gmail.com  Tue Jul 14 20:11:49 2009
From: magawake at gmail.com (Mag Gam)
Date: Tue, 14 Jul 2009 20:11:49 -0400
Subject: compiling python
Message-ID: <1cbd6f830907141711s4b6dbbe6gd563a3e63fc53b4@mail.gmail.com>

At my university we are trying to compile python with --enable-shared
however when I do a make many things fail. Is it a good idea to
compile python with shared libraries? It seems mod-python needs it
this way.

TIA


From keith at nekotaku.com  Tue Jul 14 20:29:43 2009
From: keith at nekotaku.com (Alagalah)
Date: Tue, 14 Jul 2009 17:29:43 -0700 (PDT)
Subject: Reading floats from Excel using COM
Message-ID: <04a50999-3934-4235-b047-5135d8c71c94@m11g2000yqh.googlegroups.com>

Hi, I am using the Range function to return a tuple from Excel.

The data in the range (nREVENUE) in the excel file is 100.0, 101.0,
102.0, 103.0, 104.0

I can successfully iterate across the tuple and list, but when I try
and cast to a float to do some math, I get:

  File "C:\Python25\lib\site-packages\win32com\client\__init__.py",
line 454, in __getattr__
    raise AttributeError, "'%s' object has no attribute '%s'" % (repr
(self), attr)
AttributeError: '<win32com.gen_py.Microsoft Excel 12.0 Object
Library.Range instance at 0x37766608>' object has no attribute
'__float__'

**** CODE *****
import win32com.client
import os

excel=win32com.client.Dispatch("Excel.Application")
excel.Visible=0
excel.DisplayAlerts=False

#This is the file that contains the macro
xlsname=os.path.join(os.getcwd(),"nametest.xlsx")
nametest=excel.Workbooks.Open(xlsname)

revenue_list=excel.Range("nREVENUE")

revenue=[]
revenue.extend(revenue_list)

for i in range(len(revenue)):
    rev=revenue[i]
    print float(rev)

excel.Quit()
del excel

****************

I need to use COM as I will eventually need formula support, otherwise
I would use xlutils.

Any advice on how to cast the elements to a float would be greatly
appreciated!


From greg at cosc.canterbury.ac.nz  Tue Jul 14 20:32:25 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 15 Jul 2009 12:32:25 +1200
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <7c4mb4F261slsU1@mid.individual.net>

Deep_Feelings wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and  what negatives or positives it has ?

This summarises my reasons for choosing Python
fairly well:

http://www1.american.edu/cas/econ/faculty/isaac/choose_python.pdf

-- 
Greg


From suruti94 at gmail.com  Tue Jul 14 20:42:55 2009
From: suruti94 at gmail.com (Mohan Parthasarathy)
Date: Tue, 14 Jul 2009 17:42:55 -0700
Subject: Calling functions: Why this complicated ?
In-Reply-To: <50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
Message-ID: <89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>

Chris,
Thanks for your clarifications


> > I am a newbie. I am reading
> > http://www.network-theory.co.uk/docs/pytut/KeywordArguments.html
> > Defining a function with "N" arguments and calling them in "M" different
> > ways. Why does it have to be this complicated ? I like the idea of
> calling
> > the function by explicitly naming the arguments, but there are so many
> other
> > ways here that is very confusing. Do people really use all these features
> ?
> > Perhaps, there is a equivalent book to "Javascript: Good Parts" for
> Python ?
>
> Oh $DEITY, don't even compare Python to JavaScript. At least in
> Python, when you try to access a non-existent attribute, a proper
> NameError exception is thrown rather than silently getting back
> "undefined"... (*has traumatic horror story flashback*)


I did not try to compare python to Javascript.  Just because there are ten
different ways of doing certain things, not all of them may be used. Over a
period of time, people tend to use certain features more and more.

Javascript is  a different beast where some of the features need to be
avoided for writing good programs. I don't know anything about python. But
it is possible that there is a subset that people use frequently which may
be sufficient to write good programs. Sure, that would not help me the
python interview test :-)

>
> The calling syntax is not so much complicated as it is liberating.
> Are you a C junkie who has never heard of named arguments?
>    Just use the call sequence like you've always done.
> Are you a exacting Smalltalk or Objective-C person who likes to name
> all the arguments all the time for clarity?
>    You can do that.


That's where I fit. I did not expect to see more than that :-)


> Do you want to call a function with lots of default arguments but only
> want to override a couple of them?
>    Specifying them by name lets you do that succinctly.
> Do you not want to have to worry about the order of the parameters
> because it seems kinda arbitrary?
>    Then specify the arguments by name.
> etc...
>
> And if you try and specify an argument twice, Python will throw an
> error, so anything truly confusing will get caught right away.
> And there's only one definition syntax, so while the call could be
> complicated, figuring out what it means by looking to the definition
> is fairly easy.
>
> There really aren't that many ways it's done in practice. In practice,
> the following styles cover 90% of cases:
> - All named arguments: foo(bar=a, baz=b, qux=c)
> - All sequential arguments: foo(a, b, c)
> - All sequential arguments, with a few optional arguments given by
> name: foo(a, b, c, flag=True, style=qux)

- Simple pass-through: foo(*args, **kwargs)
>
> Granted, there's 4 of them, but each taken by itself seems pretty easy
> to read, IMHO.


So, all four of them above has its use cases in practice i guess.

thanks
mohan



>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090714/d9a110f8/attachment-0001.html>

From clp2 at rebertia.com  Tue Jul 14 20:44:12 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 14 Jul 2009 17:44:12 -0700
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <7c4mb4F261slsU1@mid.individual.net>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<7c4mb4F261slsU1@mid.individual.net>
Message-ID: <50697b2c0907141744q61489a81t111d4545828d2b09@mail.gmail.com>

On Tue, Jul 14, 2009 at 5:32 PM, greg<greg at cosc.canterbury.ac.nz> wrote:
> Deep_Feelings wrote:
>>
>> So you have chosen programming language "x" so shall you tell us why
>> you did so , and ?what negatives or positives it has ?
>
> This summarises my reasons for choosing Python
> fairly well:
>
> http://www1.american.edu/cas/econ/faculty/isaac/choose_python.pdf

+1 PDF Of The Week

- Chris
-- 
http://blog.rebertia.com


From martin.hellwig at dcuktec.org  Tue Jul 14 20:50:44 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Wed, 15 Jul 2009 01:50:44 +0100
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <h3iptj$ave$1@panix3.panix.com>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
	<h3iptj$ave$1@panix3.panix.com>
Message-ID: <uYSdndiUF4t7usDXnZ2dnUVZ8nBi4p2d@bt.com>

Aahz wrote:
> In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
> Stefan Behnel  <stefan_ml at behnel.de> wrote:
>> Deep_Feelings wrote:
>>> So you have chosen programming language "x" so shall you tell us why
>>> you did so , and  what negatives or positives it has ?
>> *duck*
> 
> Where do you get the duck programming language?

Probably floated around in the same C.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From sjmachin at lexicon.net  Tue Jul 14 21:05:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 15 Jul 2009 01:05:16 +0000 (UTC)
Subject: Reading floats from Excel using COM
References: <04a50999-3934-4235-b047-5135d8c71c94@m11g2000yqh.googlegroups.com>
Message-ID: <loom.20090715T010230-316@post.gmane.org>

Alagalah <keith <at> nekotaku.com> writes:

> 
> Hi, I am using the Range function to return a tuple from Excel.

[big snip]

Exact duplicate of question asked by "KB" on
http://groups.google.com/group/python-excel ... see my answer there.






From lawson89 at gmail.com  Tue Jul 14 21:34:05 2009
From: lawson89 at gmail.com (Rick Lawson)
Date: Tue, 14 Jul 2009 18:34:05 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
Message-ID: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>

Appreciate any help on this. I am porting an app from Java to python
and need generic object pooling with hooks for object initialization /
cleanup and be able to specify an object timeout.

Thanks !
Rick


From cmpython at gmail.com  Tue Jul 14 21:52:32 2009
From: cmpython at gmail.com (Che M)
Date: Tue, 14 Jul 2009 18:52:32 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
Message-ID: <7ba1ea2b-0886-4972-abb3-5dd77a95aa1e@d4g2000yqa.googlegroups.com>

On Jul 14, 11:55?am, Deep_Feelings <doctore... at gmail.com> wrote:
> So you have chosen programming language "x" so shall you tell us why
> you did so , and ?what negatives or positives it has ?

As a hobbyist--and not a real programmer*--I think I chose Python
(I don't really recall now) because of things like:

- There is a good community, including tutor list, etc.
- I wanted something that would run cross-platform (so no Visual
Basic).
- Preferred something free (so no REALBasic).
- I wanted a high level language.
- It seemed easiest to read and learn.  I like mandatory indents, for
example.
- There are a lot of libraries for it with good support.
- I liked the Zen of Python philosophy (to the extent I understood
it).
- Some high profile entities were using it, so it must have something
going for it.
- It was new enough to be a possible improvement over older languages
  while old enough to be established.
- Who can't like a computer language named Python?

Drawbacks:

- AFAIK, running multiple Python apps all show up in the Windows task
manager as
  "python.exe" (common to all non-compiled languages?) instead of the
app's name.
- Distributing as an executable is not as straightforward as I might
hope.
- I wish Python 3 wouldn't break my 2.5 code.
- If it could be quicker (compiled), that would be better. (But
haven't tried
  psyco or Shed Skin, etc.)
- I've found understanding web programming hard, but that might be
just the
  nature of web programming and not a Python thing.
- I wish wxPython had a more complete rich text editor (but overall it
is great).

CM


From http  Tue Jul 14 22:36:22 2009
From: http (Paul Rubin)
Date: 14 Jul 2009 19:36:22 -0700
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
	<xcadneiIYYK1GcHXnZ2dnUVZ_qadnZ2d@pdx.net>
	<5e8d271a-e3e7-451b-92ca-b5321da9b706@o6g2000yqj.googlegroups.com>
Message-ID: <7xab36oeop.fsf@ruckus.brouhaha.com>

Douglas Alan <darkwater42 at gmail.com> writes:
> I can't see that a binary search tree would typically have
> particularly good cache-friendliness, so I can't see why a flat-array
> representation, such as is done for a binary heap, would have
> particularly worse cache-reference.

That is a good point.  Maybe we should be paying more attention to
cache-oblivious algorithms.

  http://en.wikipedia.org/wiki/Cache-oblivious_algorithm

H. Prokop's masters' thesis cited in the wiki article explains the
subject very well.  A fair amount of work has been done on it since
then, but not as much as one might expect.


From davea at dejaviewphoto.com  Tue Jul 14 22:51:25 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Tue, 14 Jul 2009 22:51:25 -0400
Subject: explode()
In-Reply-To: <6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
References: <59ji5593i6nvcs6j69bfk635ofstlgja0e@4ax.com>	<mailman.3019.1247363434.8015.python-list@python.org>	<eb9o55dgth91rj19iorvh1l1qlknt9iu2a@4ax.com>	<mailman.3074.1247549579.8015.python-list@python.org>
	<6k9o55p6dv04bc3scqompmek9c8rmjdu2m@4ax.com>
Message-ID: <4A5D442D.2040600@dejaviewphoto.com>


> 	The one thing I really dislike about Python over PHP is that
> Python can usually only appear in the cgi directory (unless other
> arragements are made with your hosting provider or if you reconfigure
> Apache on your own server if you have your own).  With PHP, I can put
> them in any folder on my Web site without any problem.  
>
> 	Regards, 
>
>
>
>
> 						Fred 
>
>   
You should talk to your hosting provider.  With mine, all you need do 
differently for directories other than cgi-bin is to do a chmod on the 
file to make it executable.  Have you tried that?  Is it hosted on Unix 
or Windows?

DaveA



From jmcmonagle at NO.SPAM.velseis.com.au  Tue Jul 14 23:06:18 2009
From: jmcmonagle at NO.SPAM.velseis.com.au (John McMonagle)
Date: Wed, 15 Jul 2009 13:06:18 +1000
Subject: Tkinter / Entry widget problem
In-Reply-To: <mailman.3066.1247516702.8015.python-list@python.org>
References: <mailman.3066.1247516702.8015.python-list@python.org>
Message-ID: <4A5D47AA.7090007@NO.SPAM.velseis.com.au>

Andras Szabo wrote:
> Hello. I searched the archives but couldn't find a solution to a problem
> related to the Entry widget in Tkinter.
> 
> When creating a pop-up window in an app, which contains an Entry widget,
> I want this widget to contain some default string, to have all this
> default string selected (as if the user had manually selected
> everything), and to have the focus transferred to this widget.
> 
> (The idea is then that if the window pops up, the user won't have to
> click or press Tab any more before being able to type what is needed in
> the textbox, overwriting what is written there already.)
> 
> I thought this might be the way to go:
> 
> entrybox=Entry(toplevel_parent_window)
> entrybox.insert(0,"Some default string")
> entrybox.select_range(0,END)
> entrybox.focus_set()
> entrybox.pack()
> 
> But it doesn't seem to work - the focus is not transferred to the Entry
> widget, and the text does not appear to be selected (even though after
> this entrybox.selection_present() returns True).
> 
> What am I doing wrong?
> 
> andras

You're probably not updating after the focus_set.

Try the following:

from Tkinter import *
r = Tk()


def click():
    t = Toplevel(r)
    e = Entry(t)
    e.pack()
    b = Button(t, text='Close', command=t.destroy)
    b.pack()
    e.insert(0, 'Default')
    e.select_range(0, END)
    e.focus_set()
    r.update()



b = Button(r, text='Press', command=click)
b.pack()

r.mainloop()



Regards,

John


From davea at ieee.org  Tue Jul 14 23:32:21 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 14 Jul 2009 23:32:21 -0400
Subject: How to keep a function as a generator function when the yield
	operator	is moved into its sub-functions??
In-Reply-To: <4A5CC86A.9070907@lbl.gov>
References: <4A5CC86A.9070907@lbl.gov>
Message-ID: <4A5D4DC5.1090202@ieee.org>

weafon wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Hi guys,
>
> I have a question about the usage of yield. As shown in the below 
> example, in general, if there is a code segment commonly used by two 
> or more functions, we may isolate the segment into a function and then 
> call it from other functions if necessary.
>
> def func1():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
>
>
> def func2():
>    ....
>    while(cond):
>        .....
>        commoncode()
>        ...
>
> def commoncode()
>    AAAA
>    BBBB
>    CCCC
>
> However, if there is a 'yield' operation in the common code segment, 
> the isolation causes that func1 and func2 become a non-generator 
> function!! Although I can prevent such an isolation by just 
> duplicating the segment in func1 and func2 to keep both of them being 
> generator functions, the code may become ugly and hard to maintain 
> particularly when coomoncode() is long.
>
> The problem may be resolved if I can define the commoncode() as an 
> inline function or marco. Unfortunately, inline and marco do not seems 
> to be implemented in python. Thus, how can I isolate a common segment 
> into a function when there are yield operations in the common segment?
>
> Thanks,
> Weafon
>
You are implying there's something special or unique about yield in 
this.  Return has the same problem, and many other flow control 
constructs.   Also, variable definitions and scoping.

So you can't just copy any old bunch of adjacent lines out of two 
functions, put it into a third, and call it factoring.  Give us a 
specific example you're puzzled about, and we can try to solve it.

DaveA



From pfeldman at verizon.net  Wed Jul 15 00:07:14 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Tue, 14 Jul 2009 21:07:14 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5CFF83.9070301@mrabarnett.plus.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
Message-ID: <24491580.post@talk.nabble.com>


I appreciate the effort that people have made, but I'm not impressed with any
of the answers.  For one thing, xor should be able to accept an arbitrary
number of input arguments (not just two), and should return True if and only
if the number of input arguments that evaluate to True is odd (see
www.mathworld.com article on xor).  Here's my code:

def xor(*args):
   """xor accepts an arbitrary number of input arguments, returning True
   if and only if bool() evaluates to True for an odd number of the input
   arguments."""

   result= False

   for arg in args:
      if bool(arg): result= not result

   return result



MRAB-2 wrote:
> 
> Ethan Furman wrote:
>> Robert Kern wrote:
>>> On 2009-07-14 14:56, Dr. Phillip M. Feldman wrote:
>>>
>>>> != does do what I want, except that it doesn't indicate to someone 
>>>> reading
>>>> the code that the operands are being treated as logicals.  
>>>> (Readability is
>>>> supposed to be one of the major selling points of Python).  But, this
>>>> is
>>>> probably good enough.
>>>
>>>
>>> In the words of those greater than myself, "Not every one-liner needs 
>>> to be in the standard library."
>>>
>>> def xor(a, b):
>>>     return bool(a) != bool(b)
>>>
>> 
>> Let's see...
>> 
>>   and returns the last object that is "true"
>>   or  returns the first object that is "true"
>> 
>> so should xor return the only object that is "true", else False/None?
>> 
>> def xor(a, b)
>>     if a and b:
>>         return None
>>     elif a:
>>         return a
>>     elif b:
>>         return b
>>     else:
>>         return None
>> 
> How about:
> 
> def xor(a, b):
>      return not b and a or not a and b
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24491580.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From milesck at umich.edu  Wed Jul 15 01:08:42 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 01:08:42 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <24491580.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
	<24491580.post@talk.nabble.com>
Message-ID: <9F28E417-53B9-4CFE-A880-965B85903B34@umich.edu>

On Jul 15, 2009, at 12:07 AM, Dr. Phillip M. Feldman wrote:

> I appreciate the effort that people have made, but I'm not impressed  
> with any
> of the answers.  For one thing, xor should be able to accept an  
> arbitrary
> number of input arguments (not just two)

You originally proposed this in the context of the existing short- 
circuit boolean operators.  Those operators (being infix) take only  
two operands.

> and should return True if and only
> if the number of input arguments that evaluate to True is odd

The existing and/or operators always return the value of one of the  
operands--not necessarily True or False--which is another important  
property, but one that can't be translated fully to xor.  Given the  
lack of context in your original post, hopefully you'll forgive me  
being unimpressed by your not being impressed. :)

> Here's my code:
>
> def xor(*args):
>   """xor accepts an arbitrary number of input arguments, returning  
> True
>   if and only if bool() evaluates to True for an odd number of the  
> input
>   arguments."""
>
>   result= False
>
>   for arg in args:
>      if bool(arg): result= not result
>
>   return result

If all you want is a True or False result, I'd write it like this:

import operator
def xor(*args):
     return reduce(operator.xor, map(bool, args)) # or imap

In order to make it act more like the other logical operators, I'd use  
MRAB's 2-argument xor as the reducer--though I can't really see the  
utility.

def xor2(a, b):
     return (not b and a) or (not a and b)

def xor(*args):
     return reduce(xor2, args)

You may also find this question interesting:

http://stackoverflow.com/questions/432842/

-Miles



From amrita at iisermohali.ac.in  Wed Jul 15 02:13:06 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Wed, 15 Jul 2009 11:43:06 +0530 (IST)
Subject: one more question
Message-ID: <20300.210.212.36.65.1247638386.squirrel@www.iisermohali.ac.in>


Dear all,

Just one more thing i want to ask that suppose i have a file like:---


 47     8   ALA       H     H      7.85     0.02     1
 48     8   ALA       HA    H      2.98     0.02     1
 49     8   ALA       HB    H      1.05     0.02     1
 50     8   ALA       C     C    179.39      0.3     1
 51     8   ALA       CA    C     54.67      0.3     1
 52     8   ALA       CB    C     18.85      0.3     1
 53     8   ALA       N     N    123.95      0.3     1
107    15   ALA       H     H      8.05     0.02     1
108    15   ALA       HA    H      4.52     0.02     1

now what i want that i will make another file in which first it will write
the position of ALA lets say 8 then its name ALA and then the chemical
shift value for only three atoms C,CA and CB.

Means it will be someting like:

8  ALA  C = 179.39  CA = 54.67  CB = 18.85

I tried but its not coming.


Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From mensanator at aol.com  Wed Jul 15 02:21:21 2009
From: mensanator at aol.com (Mensanator)
Date: Tue, 14 Jul 2009 23:21:21 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com> 
	<7xab37t843.fsf@ruckus.brouhaha.com>
Message-ID: <d2872b96-3a01-437e-a83f-6fd774bb367a@n11g2000yqb.googlegroups.com>

On Jul 14, 1:47?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Mensanator <mensana... at aol.com> writes:
> > - unlimited precision integers
> > - easy to program
> > - IDE not required
> > - reasonable speed
> > - math library needs to include number theoretic functions
> > ? like GCD, LCM, Modular Inverse, etc.
> > - not fucking retarded like F#
>
> Have you looked at Haskell?
>
> > As for negatives, the GMP library doesn't factor.
>
> Maybe with some MIRACL bindings...

That's the factoring program (factor.exe from
the MIRACL package) I made reference to.

I don't know how to fix the bug nor how to bind
it to Python.

What I do (or did at one time) know is how figure
out how to recompile it, change the output to be
database compatible, consistent messages rather
than such useless messages as "this number is prime".

The Python program, as it captures the StdOut,
can watch for the bug. The bug is that factor.exe
occasionally gets stuck on a composite while deep
into the factoring process. Sometimes, however,
this getting stuck can be resolved if you send the
composite back to the beginning and start over.
The factor.exe program isn't smart enough to try
this, it simply returns COMPOSITE amongst the
PRIME_FACTORS. The calling Python program can then
collect the unfactored composites and call factor.exe
again with each of them sending them back to the
start of the factoring. If they successfully factor
on the second pass, Python then appends them to
the factors from the first pass to achieve a complete
factorization that factor.exe can produce in theory
but not in practice.


From mensanator at aol.com  Wed Jul 15 02:35:15 2009
From: mensanator at aol.com (Mensanator)
Date: Tue, 14 Jul 2009 23:35:15 -0700 (PDT)
Subject: why did you choose the programming language(s)you currently use?
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<70ac8b34-bf03-493b-b0c0-7d85e7a9eb94@d4g2000vbm.googlegroups.com> 
	<7xab37t843.fsf@ruckus.brouhaha.com>
	<pan.2009.07.14.21.58.28.860000@nowhere.com>
Message-ID: <4b2e00a3-d09c-4c9a-bcfb-8c89af262963@i6g2000yqj.googlegroups.com>

On Jul 14, 4:58?pm, Nobody <nob... at nowhere.com> wrote:
> On Tue, 14 Jul 2009 11:47:08 -0700, Paul Rubin wrote:
> >> - unlimited precision integers
> >> - easy to program
> >> - IDE not required
> >> - reasonable speed
> >> - math library needs to include number theoretic functions
> >> ? like GCD, LCM, Modular Inverse, etc.
> >> - not fucking retarded like F#
>
> > Have you looked at Haskell?
>
> Given his comment about F#, I have a suspicion that he might be
> dogmatically opposed to functional languages generally.

Not dogmatically opposed, I installed it because
I actually wanted to try functional progrsmming.
My mistake was listening to that Harrop dude who
didn't bother to explain that F# is part of a
government program that provides jobs for retards.

To wit: F# has a rational data type, that's cool.
But wait, F# has TWO rational data types. Huh?
Well, after they made the first, some jackass
came up with a second type that stores data more
efficiently.

And, of course, the second type doesn't have the
same functionality as the first, so you need both.

And of the myriad data type converion methods, guess
which possible conversion methods are conspicuous
by their absense? That's right, type1 <==> type2
rational conversions don't exist.

At that point, I decided I wasn't going to put up
crap like that and threw it away.


From timr at probo.com  Wed Jul 15 02:43:10 2009
From: timr at probo.com (Tim Roberts)
Date: Tue, 14 Jul 2009 23:43:10 -0700
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<mailman.3110.1247601365.8015.python-list@python.org>
Message-ID: <ueuq55t6f4sjqut49o92gkq263ad1u2f0q@4ax.com>

"Dr. Phillip M. Feldman" <pfeldman at verizon.net> wrote:
>
>Here's a related issue: I would like to see an option for type checking on
>operands of logical operators, so that attempting to apply a logical
>operator to non-Boolean entities generates a warning message.  With operand
>type checking, 'xor' and != would be different.

How would you define "Boolean entities"?  Do you mean the True and False
values?  Such a change would break virtually every Python program ever
written.

In any case, this idea is dead in the water.  It would break a whole bunch
of existing code from before the conditional operator:

    xxx = testme and truevalue or falsevalue
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From wuwei23 at gmail.com  Wed Jul 15 02:50:08 2009
From: wuwei23 at gmail.com (alex23)
Date: Tue, 14 Jul 2009 23:50:08 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org>
Message-ID: <045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com>

amr... at iisermohali.ac.in wrote:
> I tried but its not coming.

How much are you prepared to pay for help with this? Or are you just
asking us to do all the work for you?


From wuwei23 at gmail.com  Wed Jul 15 02:56:57 2009
From: wuwei23 at gmail.com (alex23)
Date: Tue, 14 Jul 2009 23:56:57 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com>
Message-ID: <c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com>

On Jul 15, 4:50?pm, alex23 <wuwe... at gmail.com> wrote:
> amr... at iisermohali.ac.in wrote:
> > I tried but its not coming.
>
> How much are you prepared to pay for help with this? Or are you just
> asking us to do all the work for you?

Or to be a _little_ less blunt: if you want people here to _assist_
you with _your_ code, then post what you've tried here, along with
tracebacks if errors are occurring, or an explanation as to what it
isn't doing that you require.

Spawning a new thread restating your question every time someone
suggests you RTFM isn't the best way to show that you're actually
trying to solve this issue yourself.


From clp2 at rebertia.com  Wed Jul 15 03:05:14 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 00:05:14 -0700
Subject: one more question
In-Reply-To: <20300.210.212.36.65.1247638386.squirrel@www.iisermohali.ac.in>
References: <20300.210.212.36.65.1247638386.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907150005q30917bf1i88cde982b54a3bdf@mail.gmail.com>

On Tue, Jul 14, 2009 at 11:13 PM, <amrita at iisermohali.ac.in> wrote:
>
> Dear all,
>
> Just one more thing i want to ask that suppose i have a file like:---
>
>
> ?47 ? ? 8 ? ALA ? ? ? H ? ? H ? ? ?7.85 ? ? 0.02 ? ? 1
> ?48 ? ? 8 ? ALA ? ? ? HA ? ?H ? ? ?2.98 ? ? 0.02 ? ? 1
> ?49 ? ? 8 ? ALA ? ? ? HB ? ?H ? ? ?1.05 ? ? 0.02 ? ? 1
> ?50 ? ? 8 ? ALA ? ? ? C ? ? C ? ?179.39 ? ? ?0.3 ? ? 1
> ?51 ? ? 8 ? ALA ? ? ? CA ? ?C ? ? 54.67 ? ? ?0.3 ? ? 1
> ?52 ? ? 8 ? ALA ? ? ? CB ? ?C ? ? 18.85 ? ? ?0.3 ? ? 1
> ?53 ? ? 8 ? ALA ? ? ? N ? ? N ? ?123.95 ? ? ?0.3 ? ? 1
> 107 ? ?15 ? ALA ? ? ? H ? ? H ? ? ?8.05 ? ? 0.02 ? ? 1
> 108 ? ?15 ? ALA ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
>
> now what i want that i will make another file in which first it will write
> the position of ALA lets say 8 then its name ALA and then the chemical
> shift value for only three atoms C,CA and CB.
>
> Means it will be someting like:
>
> 8 ?ALA ?C = 179.39 ?CA = 54.67 ?CB = 18.85
>
> I tried but its not coming.

Surely a colleague at IISER Mohali's Computer Science department
should be able to help you?

Cheers,
Chris
-- 
http://blog.rebertia.com

From koranthala at gmail.com  Wed Jul 15 03:24:52 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 00:24:52 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org>
Message-ID: <19b3cb31-643c-47f4-9153-52e15289e933@24g2000yqm.googlegroups.com>

On Jul 15, 11:13?am, amr... at iisermohali.ac.in wrote:
> Dear all,
>
> Just one more thing i want to ask that suppose i have a file like:---
>
> ?47 ? ? 8 ? ALA ? ? ? H ? ? H ? ? ?7.85 ? ? 0.02 ? ? 1
> ?48 ? ? 8 ? ALA ? ? ? HA ? ?H ? ? ?2.98 ? ? 0.02 ? ? 1
> ?49 ? ? 8 ? ALA ? ? ? HB ? ?H ? ? ?1.05 ? ? 0.02 ? ? 1
> ?50 ? ? 8 ? ALA ? ? ? C ? ? C ? ?179.39 ? ? ?0.3 ? ? 1
> ?51 ? ? 8 ? ALA ? ? ? CA ? ?C ? ? 54.67 ? ? ?0.3 ? ? 1
> ?52 ? ? 8 ? ALA ? ? ? CB ? ?C ? ? 18.85 ? ? ?0.3 ? ? 1
> ?53 ? ? 8 ? ALA ? ? ? N ? ? N ? ?123.95 ? ? ?0.3 ? ? 1
> 107 ? ?15 ? ALA ? ? ? H ? ? H ? ? ?8.05 ? ? 0.02 ? ? 1
> 108 ? ?15 ? ALA ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
>
> now what i want that i will make another file in which first it will write
> the position of ALA lets say 8 then its name ALA and then the chemical
> shift value for only three atoms C,CA and CB.
>
> Means it will be someting like:
>
> 8 ?ALA ?C = 179.39 ?CA = 54.67 ?CB = 18.85
>
> I tried but its not coming.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA

This is indeed possible and should be quite easy. One problem is that
I do not exactly understand the problem - how do you decide which all
to join and print? Is it ALA with 4th field as C or 6th field as 0.3?
The issue here is that I am not getting the context of your problem.
And I have *no* idea about the Chemical shift etc which you are
talking about.
If you can explain it a little more, I will try something out.

Just for the scenario you explained, this code will suffice -
f = open('abcd')
d = {}
for line in f:
    fields = line.split()
    if fields[2] == 'ALA':
        d.setdefault('ALA', {'position':fields[1], 'values':[]})
        if fields[4] == 'C':
            d['ALA']['values'].append({fields[3]:fields[5]})

print d

But i dont think this is what you want


From piet at cs.uu.nl  Wed Jul 15 03:42:15 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 09:42:15 +0200
Subject: Efficient binary search tree stored in a flat array?
References: <ae6c3191-1167-43eb-9d36-23c7c49b5876@l28g2000vba.googlegroups.com>
	<h3g3ji$p90$1@panix3.panix.com>
	<5efddf9d-e6c6-47af-b0c2-f6a1be5a1a90@f16g2000vbf.googlegroups.com>
	<m2r5wjzcr7.fsf@cs.uu.nl>
	<95f25380-d71f-41b6-82b8-f991551e8a1a@32g2000yqj.googlegroups.com>
	<01ea9a41-5885-4df3-91ae-24cfa5bfbec4@y17g2000yqn.googlegroups.com>
Message-ID: <m2zlb6xui0.fsf@cs.uu.nl>

>>>>> Douglas Alan <darkwater42 at gmail.com> (DA) wrote:

>DA> I wrote:
>>> On Jul 14, 8:10?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>>> 
>>> > Of course you can take any BST algorithm and replace pointers by indices
>>> > in the array and allocate new elements in the array. But then you need
>>> > array elements to contain the indices for the children explicitely.


>>> And why is this a problem?

>DA> Oh, I'm sorry -- I see what you are saying now. You're saying you can
>DA> just implement a normal binary search tree, but store the tree nodes
>DA> in an array, as if it were a chunk of memory, and use array indices as
>DA> pointers, rather than using memory addresses as pointers.

>DA> Fair enough, but I'm not sure what that would buy you. Other than,
>DA> perhaps some improved locality of reference, and the potential to
>DA> perhaps get the pointers take up less space if you know the array is
>DA> never going to grow to be very large.

My second sentence that you quoted more or less means `it doesn't buy
you much'. 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From dickinsm at gmail.com  Wed Jul 15 03:44:48 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Wed, 15 Jul 2009 00:44:48 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org> 
	<4A5CFAC4.7020300@stoneleaf.us> <4A5CFF83.9070301@mrabarnett.plus.com> 
	<mailman.3132.1247630837.8015.python-list@python.org>
Message-ID: <0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>

On Jul 15, 5:07?am, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> I appreciate the effort that people have made, but I'm not impressed with any
> of the answers. ?For one thing, xor should be able to accept an arbitrary
> number of input arguments (not just two), and should return True if and only
> if the number of input arguments that evaluate to True is odd.

Well, that's not exactly what you originally asked for.  But it's
still a one-liner:

def xor(*args): return bool(sum(map(bool, args)) % 2)

or perhaps

def xor(*args): return bool(len(filter(None, args)) & 1)

> Here's my code:
>
> def xor(*args):
> ? ?"""xor accepts an arbitrary number of input arguments, returning True
> ? ?if and only if bool() evaluates to True for an odd number of the input
> ? ?arguments."""
>
> ? ?result= False
>
> ? ?for arg in args:
> ? ? ? if bool(arg): result= not result

It's more idiomatic to say "if arg: ..." rather than "if bool
(arg): ...".

>
> ? ?return result

Mark


From koranthala at gmail.com  Wed Jul 15 03:51:23 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 00:51:23 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com>
Message-ID: <56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com>

On Jul 15, 11:56?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 15, 4:50?pm, alex23 <wuwe... at gmail.com> wrote:
>
> > amr... at iisermohali.ac.in wrote:
> > > I tried but its not coming.
>
> > How much are you prepared to pay for help with this? Or are you just
> > asking us to do all the work for you?
>
> Or to be a _little_ less blunt: if you want people here to _assist_
> you with _your_ code, then post what you've tried here, along with
> tracebacks if errors are occurring, or an explanation as to what it
> isn't doing that you require.
>
> Spawning a new thread restating your question every time someone
> suggests you RTFM isn't the best way to show that you're actually
> trying to solve this issue yourself.

Alex,
   I am not sure about it. It doesnt look like she(I guess) is a
programmer. In the last thread, she asked the question and the reply
was to check up the regular expressions. Now, for a non-programmer, re
might be a real confusing and tough subject to grasp.
   I am not saying that what you said was wrong, only that I felt that
she got tense looking up regular expressions. So a python reply which
basically does the basic checking without going to re etc might be
more helpful for her to start her own coding.


From piet at cs.uu.nl  Wed Jul 15 04:14:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 10:14:20 +0200
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <m24otg3hkk.fsf@cs.uu.nl>
	<h3i9v6$c5t$1@panix3.panix.com> <m27hybyo95.fsf@cs.uu.nl>
	<h3j2hu$nmf$1@panix3.panix.com>
Message-ID: <m2vdluxt0j.fsf@cs.uu.nl>

>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:

>A> In article <m27hybyo95.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>>> 
>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>A> <piet at cs.uu.nl> wrote: 
>>> 
>>>>>> And to get c.x = 4 working you also need a __setitem__. 
>>> 
>A> Nope.  You do need __setitem__ so that this works:
>>> 
>A> c['x'] = 4
>>> 
>>> Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
>>> that was what the OP wanted (I think).

>A> c.x = 4 
>A> already updates the instance dict, so there's no need to change any class
>A> methods to support it.  That is, IME it's much better to add methods to
>A> a regular class to make it more dict-like using the built-in instance
>A> dict rather than changing any of the attribute mechanisms.  If you're
>A> really curious, I recommend trying several approaches yourself to see
>A> what works better.  ;-)

Yes, that's why I mentioned __setitem__. I just mixed up the motivation.

In [28]: class AttrDict:
   ....:     def __getitem__(self, key):
   ....:         return getattr(self, key)
   ....:     
   ....:     def __setitem__(self, key, value):
   ....:         setattr(self, key, value)
   ....:         
   ....:         

In [29]: c = AttrDict()

In [30]: c["y"] = 3

In [31]: c.y
Out[31]: 3

In [32]: c.x = 4

In [33]: c['x']
Out[33]: 4

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From hackingkk at gmail.com  Wed Jul 15 04:22:24 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Wed, 15 Jul 2009 13:52:24 +0530
Subject: select lines in python
In-Reply-To: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
References: <18540.210.212.36.65.1247592839.squirrel@www.iisermohali.ac.in>
Message-ID: <1247646144.3355.26.camel@krishna-laptop>

On Tue, 2009-07-14 at 23:03 +0530, amrita at iisermohali.ac.in wrote:
> Dear all,
> 
> Can anyone tell me that suppose i have a file having content like:
> 
>     _Atom_name
>       _Atom_type
>       _Chem_shift_value
>       _Chem_shift_value_error
>       _Chem_shift_ambiguity_code
>      1     1   PHE       H     H      8.49     0.02     1
>      2     1   PHE       HA    H      4.60     0.02     1
>      3     1   PHE       CA    C     57.83      0.3     1
>      4     2   LEU       H     H      8.23     0.02     1
>      5     2   LEU       HA    H      4.25     0.02     1
>      6     2   LEU       HB2   H      1.54     0.02     1
>      7     3   ASP       H     H      8.10     0.02     1
>      8     3   ASP       HA    H      4.52     0.02     1
>      9     3   ASP       HB2   H      2.65     0.02     1
> stop
> 
> 
> now what i want that instead of copying all the lines it will just write
> the information about PHE and ASP then how i acn do that using python
> programming.Kindly tell me the command for that.

Dear Amrita,
No one will tell you commands for your program.
We can give you logic and the way to implement it.
It is recommended that you write the code your self.
For our problem you keep a list and do a readlines() function and get
the content in your list variable.
then start looping through that list like for line in lines: where the
lines variable is your list.
Now keep comparing each line against your expected phrase and the moment
you find one, do the actions you need such as writing to a file.

happy hacking.
Krishnakant.
 



From andi at mozarellasalat.homelinux.net  Wed Jul 15 04:24:22 2009
From: andi at mozarellasalat.homelinux.net (Andreas Grommek)
Date: Wed, 15 Jul 2009 10:24:22 +0200
Subject: promlems with threading and print
Message-ID: <4A5D9236.9060008@mozarellasalat.homelinux.net>

Hi Newsgroup,

I'm new to python and I am familiarizing myself with threads (haven't done any threading in any
other language before...). I was playing around and discovered some weird behavior. Here is my code:

import threading
from time import sleep
from random import random
import sys

class MyThread(threading.Thread):

    def __init__(self, t, s):
        self.threadmarker = t
        self.sleeptime = s
        threading.Thread.__init__(self)

    def run(self):
        print("Tread", self.threadmarker, "is going to sleep for a while...")
        sys.stdout.flush()     #flush I/O
        sleep(self.sleeptime)  #go to sleep
        print("Tread", self.threadmarker, "is waking up and terminating")

a = 1
b = 20
for n in range(a, b):
   x = MyThread(n,random()*10.0)
   x.start()


This should create some threads which print messages, go to sleep for a random amount of time (max
10 seconds) and return with a message. When I run the code I get something like this (always different):

Tread 1 is going to sleep for a while...
Tread 2 is going to sleep for a while...
Tread 3 is going to sleep for a while...
Tread 4 is going to sleep for a while...
Tread 5 is going to sleep for a while...
Tread 6 is going to sleep for a while...
Tread 6 is going to sleep for a while...
Tread 7 is going to sleep for a while...
Tread 7 is going to sleep for a while...
Tread 7 is going to sleep for a while...
Tread 8 is going to sleep for a while...
(...)

Some "going to sleep" messages appear more than once. If I increase the number of thread the problem
gets worse and threads are even started out of order (but this alone would not worry me...).

Are some threads startet more than once or is this an issue with print? What else can I do in
addition to sys.stdout.flush() after the first print statement? Are print and sleep thread-safe? Or
is this a bug (I use python 3.1)

Any hints and help for an newbie would be appreciated.

Thanks,
Andi


From p.f.moore at gmail.com  Wed Jul 15 04:31:13 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Wed, 15 Jul 2009 09:31:13 +0100
Subject: why did you choose the programming language(s)you currently use?
In-Reply-To: <AsedncM--I7RjcDXnZ2dnUVZ_rudnZ2d@pdx.net>
References: <0427422e-9f20-4999-a601-9262f6d67632@h30g2000vbr.googlegroups.com>
	<4a5ccdd6$0$32679$9b4e6d93@newsspool2.arcor-online.net>
	<h3iptj$ave$1@panix3.panix.com>
	<AsedncM--I7RjcDXnZ2dnUVZ_rudnZ2d@pdx.net>
Message-ID: <79990c6b0907150131x73370fa3iaa095564fe729a51@mail.gmail.com>

2009/7/15 Scott David Daniels <Scott.Daniels at acm.org>:
> Aahz wrote:
>>
>> In article <4a5ccdd6$0$32679$9b4e6d93 at newsspool2.arcor-online.net>,
>> Stefan Behnel ?<stefan_ml at behnel.de> wrote:
>>>
>>> Deep_Feelings wrote:
>>>>
>>>> So you have chosen programming language "x" so shall you tell us why
>>>> you did so , and ?what negatives or positives it has ?
>>>
>>> *duck*
>>
>> Where do you get the duck programming language?
>
> It shares a type system with Python, of course. ?:-)

No, it just has a type system with all the same operations as Python,
which all do the same things. :-)

Paul.


From alessiogiovanni.baroni at gmail.com  Wed Jul 15 04:41:49 2009
From: alessiogiovanni.baroni at gmail.com (tuxagb)
Date: Wed, 15 Jul 2009 01:41:49 -0700 (PDT)
Subject: A question of style .....
Message-ID: <430dc862-7c94-4616-a66c-5ed2c033442f@n11g2000yqb.googlegroups.com>

If I have to write an extension module with many objects, how can I
organizing the code?
I think: every object in a separate file, and a last file with the
PyInit_..... function. But is unmenageable .....

Solutions?

Thanks!


From jgardner at jonathangardner.net  Wed Jul 15 04:53:51 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Wed, 15 Jul 2009 01:53:51 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
Message-ID: <38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>

On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
> Appreciate any help on this. I am porting an app from Java to python
> and need generic object pooling with hooks for object initialization /
> cleanup and be able to specify an object timeout.
>

Are you looking for something like a thread pool or a connection pool?
Such a thing is easy to code in Python. Might as well write one from
scratch for your particular need.

By the way, a tip for writing Python: Forget Java. If you're porting
an app, consider rewriting it from the architecture on up. You'll save
yourself time and get a better result.


From afriere at yahoo.co.uk  Wed Jul 15 04:55:33 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Wed, 15 Jul 2009 01:55:33 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org> 
	<4A5CFAC4.7020300@stoneleaf.us> <4A5CFF83.9070301@mrabarnett.plus.com> 
	<mailman.3132.1247630837.8015.python-list@python.org>
	<0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>
Message-ID: <ee4ab06b-8f38-40c9-bf5a-fccd936a8432@d32g2000yqh.googlegroups.com>

On Jul 15, 5:44?pm, Mark Dickinson <dicki... at gmail.com> wrote:
> On Jul 15, 5:07?am, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
> wrote:

[snip]

> > ? ?for arg in args:
> > ? ? ? if bool(arg): result= not result
>
> It's more idiomatic to say "if arg: ..." rather than "if bool
> (arg): ...".
>

Ah yes, but not once conditional tests, (just like logical operators),
type-check to ensure they have been supplied with Boolean entities. ;)


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 15 04:58:36 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 15 Jul 2009 08:58:36 GMT
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
	<m263dw1isv.fsf@cs.uu.nl>
	<4c2f9fdd-0840-47f3-bb43-5888340cb53b@j12g2000vbl.googlegroups.com>
	<pan.2009.07.14.03.25.53@REMOVE.THIS.cybersource.com.au>
	<93f6a517-63d8-4c80-bf19-4614b70999db@m7g2000prd.googlegroups.com>
	<pan.2009.07.14.09.14.52@REMOVE.THIS.cybersource.com.au>
	<ba24b9b8-f95d-4217-8e43-0fed8f4034b5@s6g2000vbp.googlegroups.com>
Message-ID: <pan.2009.07.15.08.58.36@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 08:53:33 -0700, Carl Banks wrote:

> On Jul 14, 2:14?am, Steven D'Aprano
> <ste... at REMOVE.THIS.cybersource.com.au> wrote:
>> On Tue, 14 Jul 2009 01:30:48 -0700, Carl Banks wrote:
>> > Seriously, do you *ever* take more than 2 seconds to consider whether
>> > you might be missing something obvious before following up with these
>> > indignant knee-jerk responses?
>>
>> Obviously not.
>>
>> [...]
>>
>> > Or would you rather let all unexpected exceptions print to standard
>> > error, which is often a black hole in non-interactive sitations?
>>
>> Fair point. Of course you're right.
> 
> I don't want to be mean or anything.  I agree with you on 95% of issues
> probably, of course I only follow up to disagree....


No problem Carl. You were right, in this instance I was being a smartarse 
and ended up being too clever for my own good. There are cases where you 
want to catch all exceptions, not to hide them, but to process them in 
some way (possibly logging the error and then exiting).



-- 
Steven


From jeremiah.dodds at gmail.com  Wed Jul 15 05:01:55 2009
From: jeremiah.dodds at gmail.com (Jeremiah Dodds)
Date: Wed, 15 Jul 2009 10:01:55 +0100
Subject: Calling functions: Why this complicated ?
In-Reply-To: <89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
	<89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
Message-ID: <12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>

On Wed, Jul 15, 2009 at 1:42 AM, Mohan Parthasarathy <suruti94 at gmail.com>wrote:

> So, all four of them above has its use cases in practice i guess.
>
> thanks
> mohan
>

As a hopefully semi-informative aside, I've been writing python code for a
few years now, and I regularly use all four forms of argument passing listed
above.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090715/284d3486/attachment-0001.html>

From jgardner at jonathangardner.net  Wed Jul 15 05:02:04 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Wed, 15 Jul 2009 02:02:04 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3122.1247615131.8015.python-list@python.org>
Message-ID: <4c01f2c4-314d-4690-8904-d19dec9f6241@k1g2000yqf.googlegroups.com>

On Jul 14, 4:48?pm, Ethan Furman <et... at stoneleaf.us> wrote:
>
> A whole family of supers. ?:)
>

You should pick up Lisp. The whole concept of a binary operator
doesn't exist over there. All the things binary operators can do, Lisp
does with 0, 1, 2, or more arguments.

[1]> (+)
0
[2]> (+ 1)
1
[3]> (+ 1 2)
3
[4]> (+ 1 2 3)
6

Once you get used to that, binary operators don't seem so useful
anymore.

The equivalent in Python is dropping the operators and replacing them
with built-in functions that take 0, 1, 2, or more arguments.


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 15 05:11:44 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 15 Jul 2009 09:11:44 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
Message-ID: <pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>

On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:

> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
> to have an 'xor' operator as well.

I've often wished there was too, for the sake of completeness and 
aesthetics, I'd love to be able to write:

a xor b

instead of defining a function xor(a, b).

Unfortunately, outside of boolean algebra and simulating electrical 
circuits, I can't think of any use-cases for an xor operator. Do you have 
any?



-- 
Steven


From pdpinheiro at gmail.com  Wed Jul 15 05:17:09 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Wed, 15 Jul 2009 02:17:09 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<mailman.3119.1247612922.8015.python-list@python.org>
Message-ID: <522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>

On Jul 15, 12:08?am, Christian Heimes <li... at cheimes.de> wrote:
> Chris Rebert wrote:
> > Using the xor bitwise operator is also an option:
> > bool(x) ^ bool(y)
>
> I prefer something like:
>
> ? ? bool(a) + bool(b) == 1
>
> It works even for multiple tests (super xor):
>
> ? if bool(a) + bool(b) + bool(c) + bool(d) != 1:
> ? ? ? raise ValueError("Exactly one of a, b, c and d must be true")
>
> Christian

"if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
1 = 0 xor 1 = 1 if you assicate to the left)


From bearophileHUGS at lycos.com  Wed Jul 15 05:25:20 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Wed, 15 Jul 2009 02:25:20 -0700 (PDT)
Subject: A question of style .....
References: <430dc862-7c94-4616-a66c-5ed2c033442f@n11g2000yqb.googlegroups.com>
Message-ID: <07945ef8-769d-4ca5-8142-0112a3a7befc@k6g2000yqn.googlegroups.com>

tuxagb:
> If I have to write an extension module with many objects, how can I
> organizing the code?
> I think: every object in a separate file, and a last file with the
> PyInit_..... function. But is unmenageable .....
>
> Solutions?

What do you think about using Cython?

Bye,
bearophile


From tim.wintle at teamrubber.com  Wed Jul 15 05:28:34 2009
From: tim.wintle at teamrubber.com (Tim Wintle)
Date: Wed, 15 Jul 2009 10:28:34 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <4c01f2c4-314d-4690-8904-d19dec9f6241@k1g2000yqf.googlegroups.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3122.1247615131.8015.python-list@python.org>
	<4c01f2c4-314d-4690-8904-d19dec9f6241@k1g2000yqf.googlegroups.com>
Message-ID: <1247650114.7759.13.camel@tim-laptop>


On Wed, 2009-07-15 at 02:02 -0700, Jonathan Gardner wrote:
> On Jul 14, 4:48 pm, Ethan Furman <et... at stoneleaf.us> wrote:
> >
> > A whole family of supers.  :)
> >
>  All the things binary operators can do, Lisp
> does with 0, 1, 2, or more arguments.

+1

n-ary operators are great, but binary operators are just syntactic sugar
for functions (which are obviously a generalisation of an n-ary operator
in python).

The fact that lisp-like languages don't expose this sugar is good for
making you think about what you're actually doing, but just like
mathematicians use binary (and unary) operators in equations rather than
working in the lambda calculus, having that sugar is useful to python.

> 
> [1]> (+)
> 0
> [2]> (+ 1)
> 1
> [3]> (+ 1 2)
> 3
> [4]> (+ 1 2 3)
> 6

c.f. :

>>> sum([])
0
>>> sum([1])
1
>>> sum([1,2])
3
>>> sum([1,2,3])
6



> Once you get used to that, binary operators don't seem so useful
> anymore.
> 
> The equivalent in Python is dropping the operators and replacing them
> with built-in functions that take 0, 1, 2, or more arguments.



From mail at timgolden.me.uk  Wed Jul 15 05:32:55 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 15 Jul 2009 10:32:55 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A5DA247.3040606@timgolden.me.uk>

Steven D'Aprano wrote:
> On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
> 
>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>> to have an 'xor' operator as well.
> 
> I've often wished there was too, for the sake of completeness and 
> aesthetics, I'd love to be able to write:
> 
> a xor b
> 
> instead of defining a function xor(a, b).
> 
> Unfortunately, outside of boolean algebra and simulating electrical 
> circuits, I can't think of any use-cases for an xor operator. Do you have 
> any?

I was pondering on this yesterday, and the only case I've
come across in my code -- and it's reasonably common --
is checking that one and only one of two params has been
passed. I have code which wants, say, an id or a name
but doesn't want both. It's hardly difficult to write the
check even now, but an built-in xor would make it fractionally
cleaner.

TJG



From jarausch at igpm.rwth-aachen.de  Wed Jul 15 05:53:28 2009
From: jarausch at igpm.rwth-aachen.de (Helmut Jarausch)
Date: Wed, 15 Jul 2009 11:53:28 +0200
Subject: convert Dbase (.dbf) files to SQLite databases
Message-ID: <7c5n8kF25pc8bU1@mid.dfncis.de>

Hi,

I have a lot of old Dbase files (.dbf) and I'll like to convert these
to SQLite databases as automatically as possible.
Does anybody know a tool/Python script to do so?

I know, I could use dbfpy and create the SQLite table and import all
data. But is there something easier?

Many thanks for a hint,

Helmut.

-- 
Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany


From hartley79 at gmail.com  Wed Jul 15 05:54:52 2009
From: hartley79 at gmail.com (hartley)
Date: Wed, 15 Jul 2009 02:54:52 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com>
Message-ID: <768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com>

On Jul 14, 2:21?pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 14, 7:22?pm, hartley <hartle... at gmail.com> wrote:> > > I'm very new at wrapping Python/C, and I have run into some problems.
>
> [snip]
>
>
>
> > > > ? ? ? ? pValue = PyObject_CallObject(pFunc,NULL);
>
> > > > pValue is now a PyList - i've even verified this with:
>
> > > > int a = PyList_Check(pValue);
> > > > ? ? ? ? printf("%d\n", a);
>
> > > > However, I want to send this PyList to another python module,
>
> > > Please explain "send" ... do you mean the C equivalent of the Python
> > > statement C_embedding.buff = the_pylist ?
>
> > > BTW C-embedding would trigger a syntax error in Python source; best to
> > > avoid ...
>
> > I'm sorry I'm not using the proper terms when trying to describe this
> > - i've never really learnt those terms, I guess i should do that one
> > day.
>
> Today would be a good day to start :-)
>
>
>
>
>
> > Imagine that the python function C-embedding.buff looks like this:
>
> > def buff(a):
> > ? ? if isinstance(a,list):
> > ? ? ? ? print "success"
>
> > I want to send, pass, call, whatever a list argument from the C code
> > onto this function. As simple as this - how can you call a function in
> > python from C, and providing a python list as an argument?
>
> > As I wrote earlier - I already have a PyList, called pValue. But I
> > have not been able to use this as an argument for C-embedding.buff
> > using the code I described last time.
>
> > > > but I
> > > > don't know how to do this. Initially I though I could just do like
> > > > above, only swapping NULL with pValue, but that is not working.
>
> > > > pName2 = PyString_FromString("C-embedding");
> > > > pModule2 = PyImport_Import(pName2);
> > > > pFunc2 = PyObject_GetAttrString(pModule2,"buff");
> > > ?Any good reason for not checking the
> > > return value for an error? [Rhetorical question; answer == "No"]
>
> > > > pValue2 = PyObject_CallObject(pFunc2,pValue);
>
> Your problem is here, in the second arg of PyObject_CallObject. It
> should be either NULL if no args are being supplied, or a tuple
> containing the args if 1 or more args are being supplied. pValue is
> the arg itself; you need to wrap it in a tuple.
>
> Seehttp://docs.python.org/c-api/object.html#PyObject_CallObject
>
> Actually you might like to use this instead (no tuple hassles):
>
> http://docs.python.org/c-api/object.html#PyObject_CallFunctionObjArgs
>
> What are you using as a source of information? Have you read this:
>
> http://docs.python.org/extending/embedding.html#pure-embedding?
>
> It contains a very thorough example of calling a Python function from
> C, with all the reference-counting and error-checking stuff and it's
> quite runnable -- I've just now compiled it and run it (1) as-is (2)
> changed to pass a list instead of multiple ints (3) changed again to
> emulate you trying to pass the list directly instead of wrapped in a
> tuple ... here's the result:
>
> TypeError: argument list must be a tuple
> Call failed
>
> Oh by the way, you can get away with C-embedding as a module name if
> you are importing it from C, but importing it from Python [so that you
> could test it independently of your C program] presents a difficulty
> (syntax error) ... better to change it to c_embedding.
>
> > > It's mainly just a matter of (1) knowing what you want to do (2)
> > > picking the API that does what you want (3) checking the returned
> > > value for error after every call.
>
> HTH,
> John

Thank you, that works! You're a genius :)

As for what I'm reading, I'm familiar with both


http://docs.python.org/c-api/
and
http://docs.python.org/extending/embedding.html#pure-embedding

but i still find it hard to read this and find the proper API. The
Python/C API reference is 162 pages!

I have a second issue that I've also struggled with, namely using
class object (don't shoot me if my terminology is off again). With the
little toy class below, i want to instansiate it, boost it, and return
it, similar to:

s = ObjectTest()
s.boostList()
return s.dispList()

but in C, of course.

so far I have:

pName = PyString_FromString("ob-test");
pModule = PyImport_Import(pName);
pFunc = PyObject_GetAttrString(pModule,"ObjectTest");
if (pFunc && PyCallable_Check(pFunc)) {

            printf("Callable\n");
		}
pObj = PyObject_CallObject(pFunc,NULL);
	if (pObj != NULL) {
	printf("WAS NOT NULL!\n");
}

At least this seems to work. However, as to how to actually
instantiate and use this class the way I described, I have no idea
which API to use. Even though I've spent lots of time reading it! Do
you have any clue here, as well?



(ob-test.py)
class ObjectTest:

	def __init__(self):
		self.list = []


	def boostList(self):
		self.list.append(1)

	def dispList(self):
		return self.list



From quentel.pierre at wanadoo.fr  Wed Jul 15 06:04:01 2009
From: quentel.pierre at wanadoo.fr (Pierre Quentel)
Date: Wed, 15 Jul 2009 03:04:01 -0700 (PDT)
Subject: select lines in python
References: <mailman.3100.1247592844.8015.python-list@python.org>
Message-ID: <f828ddb0-7370-4992-bd6e-fd3bdd07e393@c1g2000yqi.googlegroups.com>

On 14 juil, 19:33, amr... at iisermohali.ac.in wrote:
> Dear all,
>
> Can anyone tell me that suppose i have a file having content like:
>
> ? ? _Atom_name
> ? ? ? _Atom_type
> ? ? ? _Chem_shift_value
> ? ? ? _Chem_shift_value_error
> ? ? ? _Chem_shift_ambiguity_code
> ? ? ?1 ? ? 1 ? PHE ? ? ? H ? ? H ? ? ?8.49 ? ? 0.02 ? ? 1
> ? ? ?2 ? ? 1 ? PHE ? ? ? HA ? ?H ? ? ?4.60 ? ? 0.02 ? ? 1
> ? ? ?3 ? ? 1 ? PHE ? ? ? CA ? ?C ? ? 57.83 ? ? ?0.3 ? ? 1
> ? ? ?4 ? ? 2 ? LEU ? ? ? H ? ? H ? ? ?8.23 ? ? 0.02 ? ? 1
> ? ? ?5 ? ? 2 ? LEU ? ? ? HA ? ?H ? ? ?4.25 ? ? 0.02 ? ? 1
> ? ? ?6 ? ? 2 ? LEU ? ? ? HB2 ? H ? ? ?1.54 ? ? 0.02 ? ? 1
> ? ? ?7 ? ? 3 ? ASP ? ? ? H ? ? H ? ? ?8.10 ? ? 0.02 ? ? 1
> ? ? ?8 ? ? 3 ? ASP ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
> ? ? ?9 ? ? 3 ? ASP ? ? ? HB2 ? H ? ? ?2.65 ? ? 0.02 ? ? 1
> stop
>
> now what i want that instead of copying all the lines it will just write
> the information about PHE and ASP then how i acn do that using python
> programming.Kindly tell me the command for that.
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA

Hi,

The problem here is to test the values at specific colums in the file.
So I'd rather split each line into a list of values and do a test on
relevant items, like :

for line in open(filename):
    items = line.strip().split()
    if items[1] in ["ASP","PHE"]:
        (... handle this case ...)

Using re here is probably not the best way. It may happen that a
sequence appearing in a column also appears in another one ; and when
the tests become more complex the regular expression itself might
become complex, or even impossible (imagine the OP wants to test that
the numeric values are below a certain threshold)

- Pierre


From ben+python at benfinney.id.au  Wed Jul 15 06:08:13 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Wed, 15 Jul 2009 20:08:13 +1000
Subject: Teaching pylint about keyword placeholders in string formatting
Message-ID: <87bpnmjm2a.fsf@benfinney.id.au>

Howdy all,

A common idiom I use is::

    def frobnicate(warble):
        foo = complex_computation()
        bar = long.access.path.leading.to.useful.value
        baz = (lengthy + expression * with_several_parts)
        spangulate("%(warble)s: %(foo)s%(bar)s [%(baz)d]" % vars())

This allows the format of the string to be clear, and allows the
separate parts of it to have meaningful names.

However, this is causing pylint to complain::

    W:218:frobnicate: Unused argument 'warble'
    W:219:frobnicate: Unused variable 'foo'
    W:220:frobnicate: Unused variable 'bar'
    W:221:frobnicate: Unused variable 'baz'

That is, pylint is not aware that the names used by accessing the values
from the dictionary returned by ?vars()?.

This warning, when it actually *does* detect unused name bindings, is
very useful; I don't want to disable it. Nor do I want to pepper my code
with hints to pylint about each one of these, detracting significantly
from the readability which is the main point of the above idiom.

How can I make pylint aware in the general case that the above idiom
does, in fact, constitute a use of the names ?warble?, ?foo?, ?bar?, and
?baz? in the code?

-- 
 \         ?Pinky, are you pondering what I'm pondering?? ?I think so, |
  `\    Brain, but if we give peas a chance, won't the lima beans feel |
_o__)                                left out?? ?_Pinky and The Brain_ |
Ben Finney



From david.lyon at preisshare.net  Wed Jul 15 06:39:21 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Wed, 15 Jul 2009 06:39:21 -0400
Subject: convert Dbase (.dbf) files to SQLite databases
In-Reply-To: <7c5n8kF25pc8bU1@mid.dfncis.de>
References: <7c5n8kF25pc8bU1@mid.dfncis.de>
Message-ID: <942d96482771b3b7a0e4294381c5f3dd@preisshare.net>

On Wed, 15 Jul 2009 11:53:28 +0200, Helmut Jarausch
<jarausch at igpm.rwth-aachen.de> wrote:
> Hi,
> 
> I have a lot of old Dbase files (.dbf) and I'll like to convert these
> to SQLite databases as automatically as possible.
> Does anybody know a tool/Python script to do so?
> 
> I know, I could use dbfpy and create the SQLite table and import all
> data. But is there something easier?

yes...

Use OpenOffice-Scalc or MS-Office-Excel to open the table...

Export to csv....

Use SQLite Manager (https://addons.mozilla.org/en-US/firefox/addon/5817)

and use the import wizard to import your data....

It shouldn't take too long...

David


From piet at cs.uu.nl  Wed Jul 15 06:39:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 12:39:26 +0200
Subject: promlems with threading and print
References: <mailman.3139.1247646986.8015.python-list@python.org>
Message-ID: <m2k52axmap.fsf@cs.uu.nl>

>>>>> Andreas Grommek <andi at mozarellasalat.homelinux.net> (AG) wrote:

>AG> Hi Newsgroup,
>AG> I'm new to python and I am familiarizing myself with threads
>AG> (haven't done any threading in any other language before...). I was
>AG> playing around and discovered some weird behavior. Here is my code:

When you start programming with threads you should familiarize yourself
with (or better: study) the subject of parallel programming. Without
that you will make hard to find and debug errors. Fortunately this one
you did find. Many of these have to do with 'shared resources', i.e.
resources (like objects) that are used in more than one thread at the
same time, while at least one thread modifies it/them.

For a start read this: http://effbot.org/zone/thread-synchronization.htm
and then read some more elaborate literature.

>AG> import threading
>AG> from time import sleep
>AG> from random import random
>AG> import sys

>AG> class MyThread(threading.Thread):

>AG>     def __init__(self, t, s):
>AG>         self.threadmarker = t
>AG>         self.sleeptime = s
>AG>         threading.Thread.__init__(self)

>AG>     def run(self):
>AG>         print("Tread", self.threadmarker, "is going to sleep for a while...")
>AG>         sys.stdout.flush()     #flush I/O
>AG>         sleep(self.sleeptime)  #go to sleep
>AG>         print("Tread", self.threadmarker, "is waking up and terminating")

What happens here is that stdout is a shared resource that you are
modifying in different threads. So you have to protect it.

>AG> a = 1
>AG> b = 20
>AG> for n in range(a, b):
>AG>    x = MyThread(n,random()*10.0)
>AG>    x.start()


>AG> This should create some threads which print messages, go to sleep for a random amount of time (max
>AG> 10 seconds) and return with a message. When I run the code I get something like this (always different):

You can get even weirder stuff, like:

('Tread', 1, 'is going to sleep for a while...')
('Tread', 2, 'is going to sleep for a while...')
('Tread', 3, 'is going to sleep for a while...')
('Tread', 4, 'is going to sleep for a while...')
('Tread', 5, 'is going to sleep for a while...')
('Tread', 6, 'is going to sleep for a while...')
('Tread', 7, 'is going to sleep for a while...')
('Tread', 8('Tread', , 'is going to sleep for a while...'9, )'is going to sleep for a while...'
 ('Tread'), 
10, 'is going to sleep for a while...')
('Tread'('Tread', 12, 'is going to sleep for a while...')
, 11, 'is going to sleep for a while...')
('Tread', 13, 'is going to sleep for a while...')
('Tread', 14, 'is going to sleep for a while...')
('Tread', 15, 'is going to sleep for a while...')
('Tread', 16, 'is going to sleep for a while...')
('Tread', 17, 'is going to sleep for a while...')
('Tread'('Tread', 19, 'is going to sleep for a while...')
, 18, 'is going to sleep for a while...')
('Tread', 10, 'is waking up and terminating')
...

Here is a solution using locks (and at the same time I corrected
Tread->Thread

class MyThread(threading.Thread):

    def __init__(self, t, s, lock):
        self.lock = lock
        self.threadmarker = t
        self.sleeptime = s
        threading.Thread.__init__(self)

    def run(self):
        with lock:
            print("Thread", self.threadmarker, "is going to sleep for a while...")
            sys.stdout.flush()     #flush I/O
        sleep(self.sleeptime)  #go to sleep
        with lock:
            print("Thread", self.threadmarker, "is waking up and terminating")

a = 1
b = 20
lock = threading.Lock()
for n in range(a, b):
   x = MyThread(n,random()*10.0, lock)
   x.start()

If you have an older version of Python you have to replace
        with lock:
            statement
by
        lock.acquire()
        try:
            statement
        finally:
            lock.release()

or if you want to risk deadlocks:

        lock.acquire()
        statement
        lock.release()

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nicolas.chauvat at logilab.fr  Wed Jul 15 06:39:48 2009
From: nicolas.chauvat at logilab.fr (Nicolas Chauvat)
Date: Wed, 15 Jul 2009 12:39:48 +0200
Subject: [TIP] Teaching pylint about keyword placeholders in string
	formatting
In-Reply-To: <87bpnmjm2a.fsf@benfinney.id.au>
References: <87bpnmjm2a.fsf@benfinney.id.au>
Message-ID: <20090715103948.GA6248@volans.logilab.fr>

Hi,

On Wed, Jul 15, 2009 at 08:08:13PM +1000, Ben Finney wrote:
>     def frobnicate(warble):
>         foo = complex_computation()
>         bar = long.access.path.leading.to.useful.value
>         baz = (lengthy + expression * with_several_parts)
>         spangulate("%(warble)s: %(foo)s%(bar)s [%(baz)d]" % vars())
> 
> This allows the format of the string to be clear, and allows the
> separate parts of it to have meaningful names.
> 
> However, this is causing pylint to complain::
> ...
> That is, pylint is not aware that the names used by accessing the values
> from the dictionary returned by ?vars()?.
> ...

You are not the only one:
http://lists.logilab.org/pipermail/python-projects/2009-July/thread.html

Here is the ticket:
https://www.logilab.net/elo/ticket/9634

Thanks for the report. As usual, help and patches are welcome.

-- 
Nicolas Chauvat

logilab.fr - services en informatique scientifique et gestion de connaissances  


From denis-bz-gg at t-online.de  Wed Jul 15 06:46:23 2009
From: denis-bz-gg at t-online.de (denis)
Date: Wed, 15 Jul 2009 03:46:23 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com> 
	<mailman.3073.1247547957.8015.python-list@python.org>
Message-ID: <22fa2fe9-899b-407a-8e3c-49f29c86fa59@r33g2000yqn.googlegroups.com>

Sure, Aho-Corasick is fast for fixed strings; but without real
numbers / a concrete goal
> > Matt, how many words are you looking for, in how long a string ?

a simple solution is good enough, satisficing.  Matt asked "how to
make that function look nicer?"
but "nice" has many dimensions -- bicycles are nice for some tasks,
Ferraris for others.

Bytheway http://en.wikipedia.org/wiki/Aho-Corasick_algorithm has a
link to a Python implementation,
also http://en.wikipedia.org/wiki/Worse_is_Better is fun.



From fabiodib at email.it  Wed Jul 15 06:49:11 2009
From: fabiodib at email.it (fdb)
Date: Wed, 15 Jul 2009 12:49:11 +0200
Subject: dictionary inherit and method overriding
Message-ID: <h3kc78$goq$1@ger.gmane.org>

Hi all,

I need to extend and not replace the __getitem__ method of a dict class.

Here is sample the code:

>>> class myDict(dict):
...     def __getitem__(self, y):
...         print("Doing something")
...         dict.__getitem__(self, y)
...
>>> a=myDict()
>>> a["value"] = 1
>>> print a["value"]
None

As you see i get None instead of  1.

Any solutions?

Bye

-- 
FabioBD



From digitig at gmail.com  Wed Jul 15 06:54:06 2009
From: digitig at gmail.com (Tim Rowe)
Date: Wed, 15 Jul 2009 11:54:06 +0100
Subject: Calling functions: Why this complicated ?
In-Reply-To: <12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
	<89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
	<12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>
Message-ID: <aee48b3c0907150354v4d51004p55f300c690af0308@mail.gmail.com>

2009/7/15 Jeremiah Dodds <jeremiah.dodds at gmail.com>:

> As a hopefully semi-informative aside, I've been writing python code for a
> few years now, and I regularly use all four forms of argument passing listed
> above.

Curiously, I never use the all-named style in Python, whereas it's my
normal style in Ada. I shall now enter a period of self-refelection to
try to work out why I am so inconsistent :-)


-- 
Tim Rowe


From ben+python at benfinney.id.au  Wed Jul 15 07:01:07 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Wed, 15 Jul 2009 21:01:07 +1000
Subject: Teaching pylint about keyword placeholders in string	formatting
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
Message-ID: <877hyajjm4.fsf@benfinney.id.au>

Nicolas Chauvat <nicolas.chauvat at logilab.fr> writes:

> On Wed, Jul 15, 2009 at 08:08:13PM +1000, Ben Finney wrote:
> > That is, pylint is not aware that the names used by accessing the values
> > from the dictionary returned by ?vars()?.
> > ...
> 
> You are not the only one:
> http://lists.logilab.org/pipermail/python-projects/2009-July/thread.html

Thank you.

I think the thread Nicolas wanted me to see was this one:
<URL:http://lists.logilab.org/pipermail/python-projects/2009-July/001950.html>.

-- 
 \             ?I put contact lenses in my dog's eyes. They had little |
  `\   pictures of cats on them. Then I took one out and he ran around |
_o__)                                      in circles.? ?Steven Wright |
Ben Finney



From nicolas.chauvat at logilab.fr  Wed Jul 15 07:21:26 2009
From: nicolas.chauvat at logilab.fr (Nicolas Chauvat)
Date: Wed, 15 Jul 2009 13:21:26 +0200
Subject: [Python-projects] [TIP] Teaching pylint about keyword
	placeholders in string formatting
In-Reply-To: <20090715103948.GA6248@volans.logilab.fr>
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
Message-ID: <20090715112126.GA7138@volans.logilab.fr>

On Wed, Jul 15, 2009 at 12:39:48PM +0200, Nicolas Chauvat wrote:
> Here is the ticket:
> https://www.logilab.net/elo/ticket/9634

Apologies: http://www.logilab.org/ticket/9634

-- 
Nicolas Chauvat

logilab.fr - services en informatique scientifique et gestion de connaissances  


From lists at cheimes.de  Wed Jul 15 07:31:44 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 15 Jul 2009 13:31:44 +0200
Subject: dictionary inherit and method overriding
In-Reply-To: <h3kc78$goq$1@ger.gmane.org>
References: <h3kc78$goq$1@ger.gmane.org>
Message-ID: <h3ken0$qm6$1@ger.gmane.org>

fdb wrote:
> Hi all,
> 
> I need to extend and not replace the __getitem__ method of a dict class.
> 
> Here is sample the code:
> 
>>>> class myDict(dict):
> ....     def __getitem__(self, y):
> ....         print("Doing something")
> ....         dict.__getitem__(self, y)
> ....
>>>> a=myDict()
>>>> a["value"] = 1
>>>> print a["value"]
> None
> 
> As you see i get None instead of  1.
> 
> Any solutions?

How about returning the value? :]

Christian



From lists at cheimes.de  Wed Jul 15 07:37:22 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 15 Jul 2009 13:37:22 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<mailman.3119.1247612922.8015.python-list@python.org>
	<522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
Message-ID: <h3kf1i$rle$1@ger.gmane.org>

pdpi wrote:
> On Jul 15, 12:08 am, Christian Heimes <li... at cheimes.de> wrote:
>> Chris Rebert wrote:
>>> Using the xor bitwise operator is also an option:
>>> bool(x) ^ bool(y)
>> I prefer something like:
>>
>>     bool(a) + bool(b) == 1
>>
>> It works even for multiple tests (super xor):
>>
>>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>>       raise ValueError("Exactly one of a, b, c and d must be true")
>>
>> Christian
> 
> "if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
> xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
> 1 = 0 xor 1 = 1 if you assicate to the left)

I'm well aware of the fact that I've described something differently.
'xor' can be explained as 'check if exactly one element of two elements
is true'. My algorithms describes a super xor, aka 'check if exactly one
element of n elements is true'.

Christian



From dzizes451 at gmail.com  Wed Jul 15 08:07:20 2009
From: dzizes451 at gmail.com (dzizes)
Date: Wed, 15 Jul 2009 05:07:20 -0700 (PDT)
Subject: how to set timeout while colling a soap method?
In-Reply-To: <e26bf425-f06a-49c3-8ad2-e52e82f3b080@r34g2000vba.googlegroups.com>
References: <24461403.post@talk.nabble.com>
	<e26bf425-f06a-49c3-8ad2-e52e82f3b080@r34g2000vba.googlegroups.com>
Message-ID: <24496577.post@talk.nabble.com>


Yes, that is what I was looking for.

Greets!!

-- 
View this message in context: http://www.nabble.com/how-to-set-timeout-while-colling-a-soap-method--tp24461403p24496577.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From lawson89 at gmail.com  Wed Jul 15 08:09:54 2009
From: lawson89 at gmail.com (Rick Lawson)
Date: Wed, 15 Jul 2009 05:09:54 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
Message-ID: <12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>

On Jul 15, 4:53?am, Jonathan Gardner <jgard... at jonathangardner.net>
wrote:
> On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
>
> > Appreciate any help on this. I am porting an app from Java to python
> > and need generic object pooling with hooks for object initialization /
> > cleanup and be able to specify an object timeout.
>
> Are you looking for something like a thread pool or a connection pool?
> Such a thing is easy to code in Python. Might as well write one from
> scratch for your particular need.
>
> By the way, a tip for writing Python: Forget Java. If you're porting
> an app, consider rewriting it from the architecture on up. You'll save
> yourself time and get a better result.

Jonathan,

Thanks for the advice but would like to pick your brain a little more.
The pool I need is not a thread pool or db pool. I need to pool
objects which are a proxy for an external C process that communicates
via sockets. The pool is necessary because the initial connection/
authentication is expensive, plus the connection needs to be recycled
every so often due to instability on the C side. The existing Java
code uses commons-pool which incidentally is the base object pool for
a db connection pooling library (DBCP). Anyway, maybe this is just so
easy to do in Python that everyone rolls their own - but I have done a
lot of googling with no luck.

I just hate to re-invent the wheel here - I guess I should look at a
db connection pooling library and see if they have a generic object
pool somewhere in there. Any you can recommend that are more or less
standalone db connection pool libraries ?

Thanks,
Rick


From sorry.no at can.do  Wed Jul 15 08:15:53 2009
From: sorry.no at can.do (Borivoj)
Date: Wed, 15 Jul 2009 14:15:53 +0200
Subject: Need help with oo design while using TreeWidget
Message-ID: <h3kha0$8m3$1@ss408.t-com.hr>

I'm looking for objective oriented and pythonic way to solve my problem.

I'm using IDLE's TreeWidget, by inheriting TreeItem and overriding some of 
it's methods. My tree structure is defined inside treedata, which is 
xml.dom.minidom object. MenuTreeFrame is responsible for displaying the 
widget inside it's own Frame. As you can see in the source, MyTreeItem is 
one child in tree, and it's method GetSubList is responsible for creating 
it's children TreeItems.

When creating each child, I have to pass original tree structure (treedata) 
to each child. Once I implement event firing, I will have to pass Event 
reference to each child as well. There has to be a better way to make these 
references available to each child in tree. What would you recommend?

My code looks something like this (not executable, because treedata 
definition is lacking):

import Tkinter as tk
from TreeWidget import TreeItem, TreeNode, ScrolledCanvas

class MenuTreeFrame(tk.Frame):
    def __init__(self, parent, treedata):
        tk.Frame.__init__(self, parent)
        self.treedata = treedata
        sc = ScrolledCanvas(self, bg='white', width=150, 
highlightthickness=0, takefocus=1)
        self.canvas = sc.canvas
        sc.frame.pack(fill="both", expand=1)
    def update(self, dom):
        self.create(dom) # TODO: implement something smarter than recreating 
whole tree
    def create(self, dom):
        self.rootitem = DomTreeItem(dom.documentElement, self.treedata)
        self.node = TreeNode(self.canvas, None, self.rootitem)
        self.node.update()
        self.node.select()
        self.rootitem.OnSelect()
        self.node.expand()

class MyTreeItem(TreeItem):
    def __init__(self, treenode, treedata):
        self.node = treenode
        self.previously_selected = None
        self.treedata = treedata
    def GetText(self):
        return self.node.firstChild.nodeValue
    def IsExpandable(self):
        node = self.node
        return len(self.node.getElementsByTagName('node')) > 0
    def OnSelect(self):
        self.treedata.current = self.node
        # TODO: fire off the event
    def GetSubList(self):
        parent = self.node
        children = parent.childNodes
        itemlist = [MyTreeItem(node, self.treedata) for node in children if 
node.nodeName == 'node']
        return itemlist


Thanks for reading
Josip 




From fabiodib at email.it  Wed Jul 15 08:19:15 2009
From: fabiodib at email.it (fdb)
Date: Wed, 15 Jul 2009 14:19:15 +0200
Subject: dictionary inherit and method overriding
In-Reply-To: <h3ken0$qm6$1@ger.gmane.org>
References: <h3kc78$goq$1@ger.gmane.org> <h3ken0$qm6$1@ger.gmane.org>
Message-ID: <h3khg7$3ju$1@ger.gmane.org>

Only this! I'm going crazy!

Than you!

Code:


class myDict(dict):
    def __getitem__(self, y):
        print("Doing something")
        return dict.__getitem__(self, y)

a=myDict()
a["value"] = 1
print a["value"]


Christian Heimes ha scritto:
> How about returning the value? :]


-- 
FabioBD



From sjmachin at lexicon.net  Wed Jul 15 08:34:31 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 15 Jul 2009 05:34:31 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com>
Message-ID: <802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>

On Jul 15, 7:54?pm, hartley <hartle... at gmail.com> wrote:
> On Jul 14, 2:21?pm, John Machin <sjmac... at lexicon.net> wrote:
> > On Jul 14, 7:22?pm, hartley <hartle... at gmail.com> wrote:> > > I'm very new at wrapping Python/C, and I have run into some problems.

[snip]

/* the first telling */
> > > > statement C_embedding.buff = the_pylist ?
>
> > > > BTW C-embedding would trigger a syntax error in Python source; best to
> > > > avoid ...

/* the second telling */
> > Oh by the way, you can get away with C-embedding as a module name if
> > you are importing it from C, but importing it from Python [so that you
> > could test it independently of your C program] presents a difficulty
> > (syntax error) ... better to change it to c_embedding.
>
>
> As for what I'm reading, I'm familiar with both
>
> http://docs.python.org/c-api/
> andhttp://docs.python.org/extending/embedding.html#pure-embedding

You must have a very strange definition of familiarity! That section
has as I pointed out a complete working example of a C program that
calls a Python function with 1 or more arguments, complete with error
checking and reference counting. To me, familiarity would include
reading that program, understanding what it is doing (there are
copious explanations), compiling it, running it, then start making
changes (like I did) to do things like what you want to do.

> but i still find it hard to read this and find the proper API. The
> Python/C API reference is 162 pages!

It's a reference, not a novel. You needed no API that was not in the
sample program. What you should do is when you are going through the
example programs, look up each API in the reference manual to see what
the arguments are supposed to be, what other possibilities there are
(e.g. PyObject_CallObject 2nd arg is NULL or a tuple of your args),
what the return value is, what if anything is said about reference
counts, what similar APIs are there (e.g. a few called
PyObject_Callxxxxxxx)

> I have a second issue that I've also struggled with, namely using
> class object (don't shoot me if my terminology is off again). With the
> little toy class below, i want to instansiate it, boost it, and return
> it, similar to:
>
> s = ObjectTest()
> s.boostList()
> return s.dispList()

Let's break that down:

alist = s.dispList()
return alist

s.dispList (despite its name indicating "display") returns a reference
to a list. Your C program is going to return that to whom? The shell?

> but in C, of course.
>
> so far I have:
>
> pName = PyString_FromString("ob-test");

/* the third telling */
s/-/_/

"What I tell you three times is true". Just do it.

> pModule = PyImport_Import(pName);

You've imported the module. So far, I'm making the charitable
assumption that the lack of error checking is for brevity in your
posting, but is there in your actual code.

> pFunc = PyObject_GetAttrString(pModule,"ObjectTest");

You've obtained a reference to the class.

> if (pFunc && PyCallable_Check(pFunc)) {
>
> ? ? ? ? ? ? printf("Callable\n");
> ? ? ? ? ? ? ? ? }

And if there's a problem, you'll fall through and use the dud
reference to the class??

Get into the habit NOW of doing the error checking properly, after
each API call; otherwise debugging will become a nightmare. Follow the
examples in the sample program. In this case, it is necessary only to
test for NULL, and get the correct error message displayed for that.
Checking if the returned object is callable in the same if-test clouds
the issue. Checking for callability separately is quite unnecessary --
just call the object and you'll find out then if it's not callable.

> pObj = PyObject_CallObject(pFunc,NULL);
> ? ? ? ? if (pObj != NULL) {
> ? ? ? ? printf("WAS NOT NULL!\n");

Again instead of printing congratulatory messages on success, put in
proper checking for failure, get the error message printed and bale
out.

> }
>
> At least this seems to work. However, as to how to actually
> instantiate and use this class the way I described, I have no idea
> which API to use.

You don't know how to instantiate the class? What do you think was the
purpose of the PyObject_CallObject() that you just did??

> Even though I've spent lots of time reading it! Do
> you have any clue here, as well?

Let's trawl through the Python equivalent of what you want to do:

s = amodule.ObjectTest()
(1) import the module
(2) get the "objectTest" attribute of the module
(3) call it, park the result in s

s.boostList()
(1) get the "boostList" attribute of s
(2) call it ... but it's a method, maybe we need to use a different
PyObject_Callxxxxxx ... no result to park.

x = s.dispList()
(1) get the "displist" attribute of s
(2) call it (see above), park result in x
(3) do something sensible with x

>
> (ob-test.py)
> class ObjectTest:
>
> ? ? ? ? def __init__(self):
> ? ? ? ? ? ? ? ? self.list = []
>
> ? ? ? ? def boostList(self):
> ? ? ? ? ? ? ? ? self.list.append(1)
>
> ? ? ? ? def dispList(self):
> ? ? ? ? ? ? ? ? return self.list

HTH,
John


From deets at nospam.web.de  Wed Jul 15 08:40:05 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 14:40:05 +0200
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
Message-ID: <7c60ooF25j7lsU1@mid.uni-berlin.de>

Rick Lawson wrote:

> On Jul 15, 4:53?am, Jonathan Gardner <jgard... at jonathangardner.net>
> wrote:
>> On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
>>
>> > Appreciate any help on this. I am porting an app from Java to python
>> > and need generic object pooling with hooks for object initialization /
>> > cleanup and be able to specify an object timeout.
>>
>> Are you looking for something like a thread pool or a connection pool?
>> Such a thing is easy to code in Python. Might as well write one from
>> scratch for your particular need.
>>
>> By the way, a tip for writing Python: Forget Java. If you're porting
>> an app, consider rewriting it from the architecture on up. You'll save
>> yourself time and get a better result.
> 
> Jonathan,
> 
> Thanks for the advice but would like to pick your brain a little more.
> The pool I need is not a thread pool or db pool. I need to pool
> objects which are a proxy for an external C process that communicates
> via sockets. The pool is necessary because the initial connection/
> authentication is expensive, plus the connection needs to be recycled
> every so often due to instability on the C side. The existing Java
> code uses commons-pool which incidentally is the base object pool for
> a db connection pooling library (DBCP). Anyway, maybe this is just so
> easy to do in Python that everyone rolls their own - but I have done a
> lot of googling with no luck.
> 
> I just hate to re-invent the wheel here - I guess I should look at a
> db connection pooling library and see if they have a generic object
> pool somewhere in there. Any you can recommend that are more or less
> standalone db connection pool libraries ?

I don't know enough about your domain, e.g. if your pooled objects have
state or not.

Assuming that 

 - they are objects
 - they don't have state (like database connections)
 - you want to recycle them after so many calls

one of the simplest solutions would be something like this:

class AutoDestructingWrapper(object):

   MAX_CALL_COUNT = 1000

   def __init__(self, object_factory):
       self._object_factory = object_factory
       self._call_count = self.MAX_CALL_COUNT


   def __getattr__(self, name):
       if self._call_count >= self.MAX_CALL_COUNT:
          self._delegate = self._object_factory()
       return getattr(self._delegate, name)


Diez


From jeremiah.dodds at gmail.com  Wed Jul 15 09:04:12 2009
From: jeremiah.dodds at gmail.com (Jeremiah Dodds)
Date: Wed, 15 Jul 2009 14:04:12 +0100
Subject: Calling functions: Why this complicated ?
In-Reply-To: <aee48b3c0907150354v4d51004p55f300c690af0308@mail.gmail.com>
References: <89dd3da60907141340i46a6d913mb333788e85507128@mail.gmail.com>
	<50697b2c0907141631j41779ec4s782e66ddc0b467d0@mail.gmail.com>
	<89dd3da60907141742t45cd00dfnd3423d23af20c708@mail.gmail.com>
	<12cbbbfc0907150201r5a043e3cib69e7bc3e67f4a6b@mail.gmail.com>
	<aee48b3c0907150354v4d51004p55f300c690af0308@mail.gmail.com>
Message-ID: <12cbbbfc0907150604k33a6d468l387742ff0aa0a999@mail.gmail.com>

On Wed, Jul 15, 2009 at 11:54 AM, Tim Rowe <digitig at gmail.com> wrote:

>
> Curiously, I never use the all-named style in Python, whereas it's my
> normal style in Ada. I shall now enter a period of self-refelection to
> try to work out why I am so inconsistent :-)
>
>
>
I use it for functions that only (or mostly) have behaviour-modifying flags
and for functions that take more than 3 or so parameters.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090715/af589c36/attachment-0001.html>

From aahz at pythoncraft.com  Wed Jul 15 09:05:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 15 Jul 2009 06:05:30 -0700
Subject: The meaning of "="
References: <h3291j$mfu$1@reader1.panix.com> <m27hybyo95.fsf@cs.uu.nl>
	<h3j2hu$nmf$1@panix3.panix.com> <m2vdluxt0j.fsf@cs.uu.nl>
Message-ID: <h3kk6q$qn9$1@panix3.panix.com>

In article <m2vdluxt0j.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>
>>A> In article <m27hybyo95.fsf at cs.uu.nl>, Piet van Oostrum  <piet at cs.uu.nl> wrote:
>>>>>>>>> aahz at pythoncraft.com (Aahz) (A) wrote:
>>>> 
>>A> In article <m24otg3hkk.fsf at cs.uu.nl>, Piet van Oostrum
>>A> <piet at cs.uu.nl> wrote: 
>>>> 
>>>>>>> And to get c.x = 4 working you also need a __setitem__. 
>>>> 
>>A> Nope.  You do need __setitem__ so that this works:
>>>> 
>>A> c['x'] = 4
>>>> 
>>>> Sorry, I meant such that c.x = 4 does the same as c['x'] = 4 because
>>>> that was what the OP wanted (I think).
>
>>A> c.x = 4 
>>A> already updates the instance dict, so there's no need to change any class
>>A> methods to support it.  That is, IME it's much better to add methods to
>>A> a regular class to make it more dict-like using the built-in instance
>>A> dict rather than changing any of the attribute mechanisms.  If you're
>>A> really curious, I recommend trying several approaches yourself to see
>>A> what works better.  ;-)
>
>Yes, that's why I mentioned __setitem__. I just mixed up the motivation.

Gotcha.  Unfortunately, I can only respond to what you've written, not
what you intended to write.  ;-)  (There was enough misinformation
earlier in this thread that I felt being really really clear was
important.)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From pdpinheiro at gmail.com  Wed Jul 15 09:12:03 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Wed, 15 Jul 2009 06:12:03 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<mailman.3119.1247612922.8015.python-list@python.org>
	<522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
	<mailman.3152.1247657854.8015.python-list@python.org>
Message-ID: <a9ae690a-c9db-4563-b42b-c37c6521ef66@c36g2000yqn.googlegroups.com>

On Jul 15, 12:37?pm, Christian Heimes <li... at cheimes.de> wrote:
> pdpi wrote:
> > On Jul 15, 12:08 am, Christian Heimes <li... at cheimes.de> wrote:
> >> Chris Rebert wrote:
> >>> Using the xor bitwise operator is also an option:
> >>> bool(x) ^ bool(y)
> >> I prefer something like:
>
> >> ? ? bool(a) + bool(b) == 1
>
> >> It works even for multiple tests (super xor):
>
> >> ? if bool(a) + bool(b) + bool(c) + bool(d) != 1:
> >> ? ? ? raise ValueError("Exactly one of a, b, c and d must be true")
>
> >> Christian
>
> > "if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
> > xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
> > 1 = 0 xor 1 = 1 if you assicate to the left)
>
> I'm well aware of the fact that I've described something differently.
> 'xor' can be explained as 'check if exactly one element of two elements
> is true'. My algorithms describes a super xor, aka 'check if exactly one
> element of n elements is true'.
>
> Christian

Well, I just wouldn't call it a "super xor" then, when "unicity test"
works much better -- especially as an alternative to an actual xor
without any specification to the actual intended functionality except
the exception text.


From peter.fodrek at stuba.sk  Wed Jul 15 09:12:52 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Wed, 15 Jul 2009 15:12:52 +0200
Subject: import module unbelieveable behaviour
Message-ID: <200907151512.52607.peter.fodrek@stuba.sk>

Dear conference!

I have test Why python based script for HeeksCNC post-processing does not 
work...  And I've got unbelievable behavior  When importing module module 
manually it works, but same opertaion from script does not
 work as seen

/opt/HeeksCAD8/HeeksCNC> python
Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
[GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import nc.rez
>>>
/opt/HeeksCAD8/HeeksCNC> python test.py
Traceback (most recent call last):
  File "test.py", line 7, in <module>
    import nc.rez
ImportError: No module named rez


/opt/HeeksCAD8/HeeksCNC> python ./test.py
Traceback (most recent call last):
  File "./test.py", line 7, in <module>
    import nc.rez
ImportError: No module named rez


Would anyone be helpful for me to get more information about this problem 
because  pydb does not show anything usable for me,please?

I look forward hearing form you

Yours  faithfully

Peter Fodrek


From mail at microcorp.co.za  Wed Jul 15 09:37:30 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 15 Jul 2009 15:37:30 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <002101ca0551$66d1dd40$0d00a8c0@Hendrik>


"Steven D'Aprano" <steven at REMOVE.THIS.cy..e.com.au> wrote:

>Unfortunately, outside of boolean algebra and simulating electrical 
>circuits, I can't think of any use-cases for an xor operator. Do you have 
>any?

A bitwise xor is a poor man's comparator - if the result is binary zero,
the operands were equal, no matter what they represented.

Not much use in python, though.

- Hendrik






From deets at nospam.web.de  Wed Jul 15 09:43:06 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 15:43:06 +0200
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
	<7c60ooF25j7lsU1@mid.uni-berlin.de>
Message-ID: <7c64etF26e7lsU1@mid.uni-berlin.de>

Diez B. Roggisch wrote:

> Rick Lawson wrote:
> 
>> On Jul 15, 4:53?am, Jonathan Gardner <jgard... at jonathangardner.net>
>> wrote:
>>> On Jul 14, 6:34?pm, Rick Lawson <lawso... at gmail.com> wrote:
>>>
>>> > Appreciate any help on this. I am porting an app from Java to python
>>> > and need generic object pooling with hooks for object initialization /
>>> > cleanup and be able to specify an object timeout.
>>>
>>> Are you looking for something like a thread pool or a connection pool?
>>> Such a thing is easy to code in Python. Might as well write one from
>>> scratch for your particular need.
>>>
>>> By the way, a tip for writing Python: Forget Java. If you're porting
>>> an app, consider rewriting it from the architecture on up. You'll save
>>> yourself time and get a better result.
>> 
>> Jonathan,
>> 
>> Thanks for the advice but would like to pick your brain a little more.
>> The pool I need is not a thread pool or db pool. I need to pool
>> objects which are a proxy for an external C process that communicates
>> via sockets. The pool is necessary because the initial connection/
>> authentication is expensive, plus the connection needs to be recycled
>> every so often due to instability on the C side. The existing Java
>> code uses commons-pool which incidentally is the base object pool for
>> a db connection pooling library (DBCP). Anyway, maybe this is just so
>> easy to do in Python that everyone rolls their own - but I have done a
>> lot of googling with no luck.
>> 
>> I just hate to re-invent the wheel here - I guess I should look at a
>> db connection pooling library and see if they have a generic object
>> pool somewhere in there. Any you can recommend that are more or less
>> standalone db connection pool libraries ?
> 
> I don't know enough about your domain, e.g. if your pooled objects have
> state or not.
> 
> Assuming that
> 
>  - they are objects
>  - they don't have state (like database connections)
>  - you want to recycle them after so many calls
> 
> one of the simplest solutions would be something like this:
> 
> class AutoDestructingWrapper(object):
> 
>    MAX_CALL_COUNT = 1000
> 
>    def __init__(self, object_factory):
>        self._object_factory = object_factory
>        self._call_count = self.MAX_CALL_COUNT
> 
> 


This must be 

   def __getattr__(self, name):
       self._call_count += 1
       if self._call_count >= self.MAX_CALL_COUNT:
          self._delegate = self._object_factory()
          self._call_count = 0
       return getattr(self._delegate, name)

of course.

Diez


From python at mrabarnett.plus.com  Wed Jul 15 10:21:27 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 15 Jul 2009 15:21:27 +0100
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <4A5DE5E7.5070003@mrabarnett.plus.com>

Steven D'Aprano wrote:
> On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
> 
>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>> to have an 'xor' operator as well.
> 
> I've often wished there was too, for the sake of completeness and 
> aesthetics, I'd love to be able to write:
> 
> a xor b
> 
> instead of defining a function xor(a, b).
> 
> Unfortunately, outside of boolean algebra and simulating electrical 
> circuits, I can't think of any use-cases for an xor operator. Do you have 
> any?
> 
The problem is that 'and' and 'or' are not limited to Boolean values:

     'and' returns the first false value or the last true value.

     'or' returns the first true value or the last false value.

What values should 'xor' return? IMHO, if only one of the values is true
then it should return that value, otherwise it should return False.

     1 xor 0 => 1
     0 xor 2 => 2
     1 xor 2 => False
     0 xor 0 => False

This is because it's a Boolean operator, so it should fall back to
Boolean values when necessary, like 'not':

     not 0 => True
     not 1 => False

Also:

     x and y and z => (x and y) and z
     x or y or z => (x or y) or z

therefore:

     x xor y xor z => (x xor y) xor z


From skip at pobox.com  Wed Jul 15 10:22:11 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 15 Jul 2009 09:22:11 -0500
Subject: [Python-projects] [TIP] Teaching pylint about keyword
	placeholders in string formatting
In-Reply-To: <20090715103948.GA6248@volans.logilab.fr>
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
Message-ID: <19037.58899.828799.617599@montanaro.dyndns.org>


    Nicolas> Here is the ticket:
    Nicolas> https://www.logilab.net/elo/ticket/9634

Is it possible to get read-only access to the tracker?  It's prompting me
for a login which I don't have.

Thx,

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    when i wake up with a heart rate below 40, i head right for the espresso
    machine. -- chaos @ forums.usms.org


From piet at cs.uu.nl  Wed Jul 15 10:25:14 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 15 Jul 2009 16:25:14 +0200
Subject: promlems with threading and print
References: <mailman.3139.1247646986.8015.python-list@python.org>
	<m2k52axmap.fsf@cs.uu.nl>
Message-ID: <m2eisixbud.fsf@cs.uu.nl>

>>>>> Piet van Oostrum <piet at cs.uu.nl> (PvO) wrote:

>PvO>     def run(self):
>PvO>         with lock:

All the 'with lock:' lines should have been 'with self.lock:' but as
lock is also a global variable, it did work. Of course you can decide to
use only the global variable and get rid of the self.lock altogether. I
am not very fond of global variables myself, however, that's why I used
the self.lock.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aurelien.campeas at logilab.fr  Wed Jul 15 10:33:04 2009
From: aurelien.campeas at logilab.fr (=?utf-8?B?QXVyw6lsaWVuIENhbXDDqWFz?=)
Date: Wed, 15 Jul 2009 16:33:04 +0200
Subject: [Python-projects] [TIP] Teaching pylint about keyword
	placeholders in string formatting
In-Reply-To: <19037.58899.828799.617599@montanaro.dyndns.org>
References: <87bpnmjm2a.fsf@benfinney.id.au>
	<20090715103948.GA6248@volans.logilab.fr>
	<19037.58899.828799.617599@montanaro.dyndns.org>
Message-ID: <20090715143304.GJ10884@crater.logilab.fr>

On Wed, Jul 15, 2009 at 09:22:11AM -0500, skip at pobox.com wrote:
> 
>     Nicolas> Here is the ticket:
>     Nicolas> https://www.logilab.net/elo/ticket/9634
> 
> Is it possible to get read-only access to the tracker?  It's prompting me
> for a login which I don't have.
> 
> Thx,

that should be http://www.logilab.org/ticket/9634



From Bill at SynectixLtd.com  Wed Jul 15 10:37:54 2009
From: Bill at SynectixLtd.com (Bill Davy)
Date: Wed, 15 Jul 2009 15:37:54 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org><pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<mailman.3158.1247667680.8015.python-list@python.org>
Message-ID: <6Yidnc7fb6QvdMDXnZ2dnUVZ8h6dnZ2d@bt.com>

"MRAB" <python at mrabarnett.plus.com> wrote in message 
news:mailman.3158.1247667680.8015.python-list at python.org...
> Steven D'Aprano wrote:
>> On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
>>
>>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>>> to have an 'xor' operator as well.
>>
>> I've often wished there was too, for the sake of completeness and 
>> aesthetics, I'd love to be able to write:
>>
>> a xor b
>>
>> instead of defining a function xor(a, b).
>>
>> Unfortunately, outside of boolean algebra and simulating electrical 
>> circuits, I can't think of any use-cases for an xor operator. Do you have 
>> any?
>>
> The problem is that 'and' and 'or' are not limited to Boolean values:
>
>     'and' returns the first false value or the last true value.
>
>     'or' returns the first true value or the last false value.
>
> What values should 'xor' return? IMHO, if only one of the values is true
> then it should return that value, otherwise it should return False.
>
>     1 xor 0 => 1
>     0 xor 2 => 2
>     1 xor 2 => False
>     0 xor 0 => False
>
> This is because it's a Boolean operator, so it should fall back to
> Boolean values when necessary, like 'not':
>
>     not 0 => True
>     not 1 => False
>
> Also:
>
>     x and y and z => (x and y) and z
>     x or y or z => (x or y) or z
>
> therefore:
>
>     x xor y xor z => (x xor y) xor z


Gosh, let's all discuss commutation and distribution.

And surely in quantum merchanics there is something about non-commuting 
operatiomns letting in Planck's constant. 




From tycho at tycho.ws  Wed Jul 15 10:58:03 2009
From: tycho at tycho.ws (Tycho Andersen)
Date: Wed, 15 Jul 2009 09:58:03 -0500
Subject: import module unbelieveable behaviour
In-Reply-To: <200907151512.52607.peter.fodrek@stuba.sk>
References: <200907151512.52607.peter.fodrek@stuba.sk>
Message-ID: <49b3a7400907150758j77e97e95ra9b806e763eb22da@mail.gmail.com>

On Wed, Jul 15, 2009 at 8:12 AM, Peter Fodrek<peter.fodrek at stuba.sk> wrote:
>
> Would anyone be helpful for me to get more information about this problem
> because ?pydb does not show anything usable for me,please?

What is the directory structure for the HeeksCNC module? Although I'm
no expert, I suspect it looks something like:

nc/
nc/rez.py
nc/foo.py

In order for python to look in the nc/ directory for modules, there
needs to be a file called __init__.py (even if it's empty). I suspect
the nc/ directory is missing this file (although, I'm confused as to
why it would work in the interpreter then).

Tycho


From jeanmichel at sequans.com  Wed Jul 15 11:00:39 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 17:00:39 +0200
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
Message-ID: <4A5DEF17.3050107@sequans.com>

John Nagle wrote:
> walterbyrd wrote:
>> I believe Guido himself has said that all indentions should be four
>> spaces - no tabs.
>>
>> Since backward compatibility is being thrown away anyway, why not
>> enforce the four space rule?
>>
>> At least that way, when I get python code from somebody else, I would
>> know what I am looking at, without having to do a hex dump, or
>> something.
>
>    Python 3 enforces the rule that you can't mix tabs and spaces
> for indentation in the same file.  That (finally) guarantees that
> the indentation you see is what the Python parser sees.  That's
> enough to prevent non-visible indentation errors.
>
>    It also means that the Python parser no longer has to have
> any concept of how many spaces equal a tab.  So the problem
> is now essentially solved.
>
>                     John Nagle
By the way why would you prevent us from using tabs for indenting ? If 
I'm not wrong, from a semantic point of view, that's what tabs are for: 
indenting. Spaces are meant to separate tokens, aren't they ?
I love my tabs, don't take them away from me !

JM


From jeanmichel at sequans.com  Wed Jul 15 11:03:30 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 17:03:30 +0200
Subject: Colour of output text
In-Reply-To: <pan.2009.07.11.06.24.02.406000@nowhere.com>
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com>
	<h371ba$36l$1@aioe.org>
	<pan.2009.07.11.06.24.02.406000@nowhere.com>
Message-ID: <4A5DEFC2.4030602@sequans.com>

Nobody wrote:
> On Fri, 10 Jul 2009 09:23:54 +0000, garabik-news-2005-05 wrote:
>
>   
>>>> I would like to learn a way of changing the colour of a particular
>>>> part of the output text. I've tried the following
>>>>         
>>> On Unix operating systems this would be done through the curses interface:
>>>
>>> http://docs.python.org/library/curses.html
>>>       
>> Or using ANSI colour codes:
>>
>> colours = {
>>             'none'       :    "",
>>             'default'    :    "\033[0m",
>>             'bold'       :    "\033[1m",
>>     
>
> [snip]
>
>   
>>             # non-standard attributes, supported by some terminals 
>>     
>
> This comment should have appeared immediately after "none" ;)
>
> Hard-coding control/escape sequences is just lame. Use the curses modules
> to obtain the correct sequences for the terminal.
>
>   
As the OP I'm really interested in doing so. I currently have all my 
colors hard-coded.
Now It may be lame but as soon as I call curses.initscr(), it's just 
messing up with my terminal, moreover I didn't figure out how to "print  
'hello'" using curses color codes.
Anyone has an example ? I'm pretty sure it may fit in one line.

JM




From jeanmichel at sequans.com  Wed Jul 15 11:15:47 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 17:15:47 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3j358$lhr$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
Message-ID: <4A5DF2A3.2080101@sequans.com>

Christian Heimes wrote:
> Chris Rebert wrote:
>   
>> Using the xor bitwise operator is also an option:
>> bool(x) ^ bool(y)
>>     
>
> I prefer something like:
>
>     bool(a) + bool(b) == 1
>
> It works even for multiple tests (super xor):
>
>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>       raise ValueError("Exactly one of a, b, c and d must be true")
>
> Christian
>
>   
While everyone's trying to tell the OP how to workaround the missing xor 
operator, nobody answered the question "why is there no xor operator ?".

If the question was "Why is there no 'or' operator ?", would "because A 
or B <=> not(not A and not B)" be a proper answer ?

JM



From MrJean1 at gmail.com  Wed Jul 15 11:15:55 2009
From: MrJean1 at gmail.com (Jean)
Date: Wed, 15 Jul 2009 08:15:55 -0700 (PDT)
Subject: Best Way to Handle All Exceptions
References: <45090ff9-6f58-4b65-b08b-78189cdbc3c4@g23g2000vbr.googlegroups.com>
Message-ID: <c7abf5e2-7ada-4bda-8c61-9b65132e704a@c1g2000yqi.googlegroups.com>

On Jul 13, 6:26?am, seldan24 <selda... at gmail.com> wrote:
> Hello,
>
> I'm fairly new at Python so hopefully this question won't be too
> awful. ?I am writing some code that will FTP to a host, and want to
> catch any exception that may occur, take that and print it out
> (eventually put it into a log file and perform some alerting action).
> I've figured out two different ways to do this, and am wondering which
> is the best (i.e. cleanest, 'right' way to proceed). ?I'm also trying
> to understand exactly what occurs for each one.
>
> The first example:
>
> from ftplib import FTP
> try:
> ? ? ftp = FTP(ftp_host)
> ? ? ftp.login(ftp_user, ftp_pass)
> except Exception, err:
> ? ? print err
>
> This works fine. ?I read through the documentation, and my
> understanding is that there is a built-in exceptions module in python,
> that is automatically available in a built-in namespace. ?Within that
> module is an 'Exception' class which would contain whatever exception
> is thrown. ?So, I'm passing that to the except, along with err to hold
> the value and then print it out.
>
> The second example:
>
> from ftplib import FTP
> import sys
> try:
> ? ? ftp = FTP(ftp_host)
> ? ? ftp.login(ftp_user, ftp_pass)
> except:
> ? ? print sys.exc_info()
>
> Here I, for the most part, get the same thing. ?I'm not passing
> anything to except and just printing out the exception using a method
> defined in the sys module.
>
> So, I'm new to Python... I've made it this far and am happy, but want
> to make sure I'm coding correctly from the start. ?Which method is the
> better/cleaner/more standard way to continue? ?Thanks for any help.



The second example is "better" if you need your code to work in Python
3.0 *and* in 2.X.

For Python 3.0, the first example has to be written as:

    ....
except Exception as err:
    ....


/Jean Brouwers


From skip at pobox.com  Wed Jul 15 11:23:22 2009
From: skip at pobox.com (skip at pobox.com)
Date: Wed, 15 Jul 2009 10:23:22 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <4A5DEF17.3050107@sequans.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<4A5DEF17.3050107@sequans.com>
Message-ID: <19037.62570.370235.287125@montanaro.dyndns.org>


    JM> By the way why would you prevent us from using tabs for indenting ?
    JM> If I'm not wrong, from a semantic point of view, that's what tabs
    JM> are for: indenting. Spaces are meant to separate tokens, aren't they
    JM> ?  I love my tabs, don't take them away from me !

I don't think your tabs have been taken away, you just can't mix them with
spaces.

Skip


From python-url at phaseit.net  Wed Jul 15 11:36:06 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Wed, 15 Jul 2009 15:36:06 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul 15)
Message-ID: <h3kt16$9nj$1@lairds.us>

QOTW:  "Everyone gets so caught up in programming via languages that you get,
well, people trying to teach 'Computer Programming' as if it were only
necessary to grok a language, rather than grokking /symbol manipulation/
itself." - Simon Forman
    http://groups.google.com/group/comp.lang.python/msg/4bc886a5d5feda14
    

    A C programmer may completely fail to guess the actual meaning of ++n
    and --n in Python:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/fa7281ce6249dec5/
    
    Building the argument list for a subprocess call *right* wasn't obvious:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/f02150fbc732f9dc/
    
    Robust way to handle all possible exceptions:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/db858ef8dfb51a47/
    
    A related question: how to safely handle Ctrl-C:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/a3ef46f47a0eac39/
    
    Started two weeks ago, this thread is now discussing about the correct
    usage of "assert":
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/b1a6ca84d3bfc483/
    
    Looking for a robust and safe way of writing a constructor when any step
    may fail:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/1dc1f1cb5fa8177a/
    
    How to define a "class" property (as opposed to normal, "instance"
    properties):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8a8b8138eada2be5/
    
    How to explain basic concepts like pass-by-object, assignment and
    mutability to beginners:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/4b5c5aa1d8b42b9c/
    later: the meaning of '=' in assignment
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3c13fd526a4d35df/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From robert.kern at gmail.com  Wed Jul 15 11:38:55 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 15 Jul 2009 10:38:55 -0500
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5DF2A3.2080101@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>
	<4A5DF2A3.2080101@sequans.com>
Message-ID: <h3kt6i$cij$1@ger.gmane.org>

On 2009-07-15 10:15, Jean-Michel Pichavant wrote:
> Christian Heimes wrote:
>> Chris Rebert wrote:
>>> Using the xor bitwise operator is also an option:
>>> bool(x) ^ bool(y)
>>
>> I prefer something like:
>>
>> bool(a) + bool(b) == 1
>>
>> It works even for multiple tests (super xor):
>>
>> if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>> raise ValueError("Exactly one of a, b, c and d must be true")
>>
>> Christian
>>
> While everyone's trying to tell the OP how to workaround the missing xor
> operator, nobody answered the question "why is there no xor operator ?".
>
> If the question was "Why is there no 'or' operator ?", would "because A
> or B <=> not(not A and not B)" be a proper answer ?

That's not the only answer the OP has been given. The most compelling answer is 
that an "xor" keyword cannot be implemented with similar semantics to "and" and 
"or", in particular short-circuiting and returning one of the actual inputs 
instead of a coerced bool.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From deets at nospam.web.de  Wed Jul 15 11:41:54 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 17:41:54 +0200
Subject: import module unbelieveable behaviour
References: <mailman.3157.1247667587.8015.python-list@python.org>
Message-ID: <7c6bdkF26j00sU1@mid.uni-berlin.de>

Peter Fodrek wrote:

> Dear conference!
> 
> I have test Why python based script for HeeksCNC post-processing does not
> work...  And I've got unbelievable behavior  When importing module module
> manually it works, but same opertaion from script does not
>  work as seen
> 
> /opt/HeeksCAD8/HeeksCNC> python
> Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
> [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import nc.rez
>>>>
> /opt/HeeksCAD8/HeeksCNC> python test.py
> Traceback (most recent call last):
>   File "test.py", line 7, in <module>
>     import nc.rez
> ImportError: No module named rez

What does 

import nc
print nc.__file__

tell you, and is that what you'd expect it to be?

Diez


From hniksic at xemacs.org  Wed Jul 15 12:14:10 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Wed, 15 Jul 2009 18:14:10 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
Message-ID: <87fxcxj54d.fsf@busola.homelinux.net>

Jean-Michel Pichavant <jeanmichel at sequans.com> writes:

> While everyone's trying to tell the OP how to workaround the missing
> xor operator, nobody answered the question "why is there no [boolean]
> xor operator ?".

Probably because there isn't one in C.  The bitwise XOR operator, on the
other hand, exists in both C and Python.

> If the question was "Why is there no 'or' operator ?", would "because
> A or B <=> not(not A and not B)" be a proper answer ?

Note that in Python A or B is in fact not equivalent to not(not A and
not B).


From ethan at stoneleaf.us  Wed Jul 15 12:25:08 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 15 Jul 2009 09:25:08 -0700
Subject: convert Dbase (.dbf) files to SQLite databases
In-Reply-To: <7c5n8kF25pc8bU1@mid.dfncis.de>
References: <7c5n8kF25pc8bU1@mid.dfncis.de>
Message-ID: <4A5E02E4.9090303@stoneleaf.us>

Helmut Jarausch wrote:
> Hi,
> 
> I have a lot of old Dbase files (.dbf) and I'll like to convert these
> to SQLite databases as automatically as possible.
> Does anybody know a tool/Python script to do so?
> 
> I know, I could use dbfpy and create the SQLite table and import all
> data. But is there something easier?
> 
> Many thanks for a hint,
> 
> Helmut.
> 

Greetings!

If your tables are either dBase III or Visual Foxpro 6 (may work with 
other VFP versions...) you can try 
http://groups.google.com/group/python-dbase

#open table
import dbf
table = dbf.Table('/path/to/old/dbf')

#generate .csv file
table.export()	# defaults to same name with csv extension

#access records
for rec in table:
     tups = tuple(rec)
     lst = list(rec)
     dct = rec.scatter_fields()

I haven't used SQlite, so I'm unable to provide samples for that portion 
of the conversion.

Hope this helps.

~Ethan~


From sjmachin at lexicon.net  Wed Jul 15 12:30:29 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 15 Jul 2009 09:30:29 -0700 (PDT)
Subject: convert Dbase (.dbf) files to SQLite databases
References: <7c5n8kF25pc8bU1@mid.dfncis.de>
	<mailman.3145.1247654594.8015.python-list@python.org>
Message-ID: <419cc0e0-3a78-4906-8420-c12ce2684bef@c36g2000yqn.googlegroups.com>

On Jul 15, 8:39?pm, David Lyon <david.l... at preisshare.net> wrote:
> On Wed, 15 Jul 2009 11:53:28 +0200, Helmut Jarausch
>
> <jarau... at igpm.rwth-aachen.de> wrote:
> > Hi,
>
> > I have a lot of old Dbase files (.dbf) and I'll like to convert these
> > to SQLite databases as automatically as possible.
> > Does anybody know a tool/Python script to do so?
>
> > I know, I could use dbfpy and create the SQLite table and import all
> > data. But is there something easier?
>
> yes...
>
> Use OpenOffice-Scalc or MS-Office-Excel to open the table...

Max 64K rows for Scalc and Excel 2003; 2007 can take 2**20 rows.
Only old dBase (not dBase 7). Memo fields not handled. Visual FoxPro
DBFs not supported by Excel even tho' VFP is an MS product.


> Export to csv....

Yuk.

>
> Use SQLite Manager (https://addons.mozilla.org/en-US/firefox/addon/5817)
>
> and use the import wizard to import your data....
>
> It shouldn't take too long...

... before you get sick of the error-prone manual tasks.

I'd write a script that took a DBF file, analysed the field
descriptions, made a CREATE TABLE statement, executed it, and then
started doing inserts. Fairly easy to write. Scripts have the great
benefit that you can fix them and re-run a whole lot easier than
redoing manual steps.

If dbfpy can't handle any new-fangled stuff you may have in your
files, drop me a line ... I have a soon-to-be released DBF module that
should be able to read the "new" stuff up to dBase7 and VFP9,
including memo files, conversion from whatever to Unicode if
needed, ...

Cheers,
John


From seldan24 at gmail.com  Wed Jul 15 12:36:13 2009
From: seldan24 at gmail.com (seldan24)
Date: Wed, 15 Jul 2009 09:36:13 -0700 (PDT)
Subject: Python Equivalent for dd & fold
Message-ID: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>

Hello,

I have a shell script, that I'm attempting to convert to Python.  It
FTP's files down from an AS/400 machine.  That part is working fine.
Once the files arrive, the script converts them from EBCDIC to ASCII
and then formats their line width based on a pre-determined size.

For example, if I have the file TESTFILE and I know it should be
formatted to 32 characters/line, I run:

dd if=TESTFILE,EBCDIC conv=ASCII | fold -w 32 > TESTFILE.ASCII

Luckily, the files have the packed decimal format common in COBOL
programs converted already prior to reaching me, so all I have to do
is the conversion and line width formatting.  The above works fine,
and I know I could (and may) just embed it using subprocess.Popen.
This, I've figured out how to do.  But, ideally, I'd like to convert
as much shell to native Python as possible, so that I can learn more.

I think I can figure out the first part by using the codecs module...
found some information on Google related to that.  My question is,
what can I use as the equivalent for the Unix 'fold' command?  I don't
really need to know how to do it, just a push in the right direction.

Thanks.


From rhodri at wildebst.demon.co.uk  Wed Jul 15 12:40:20 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 15 Jul 2009 17:40:20 +0100
Subject: select lines in python
In-Reply-To: <29449.210.212.36.65.1247598632.squirrel@www.iisermohali.ac.in>
References: <29449.210.212.36.65.1247598632.squirrel@www.iisermohali.ac.in>
Message-ID: <op.uw4a9iv6a8ncjz@gnudebst>

On Tue, 14 Jul 2009 20:10:32 +0100, <amrita at iisermohali.ac.in> wrote:

> Can i become more precise like instead of printing all lines for PHE and
> ASP is it possible that for PHE python will print only those lines which
> will have information about H and HA and for ASP it will print those  
> lines
> which will have information about HA and HB.

1) Top-posting is considered unhelpful, since it breaks the flow of
information badly.

2) To answer question: yes, you can.  However I can sense the start of an
unending flood of small changes, so I'm going to direct you back to the
Python tutorial at www.python.org rather than tell you exactly how.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From ethan at stoneleaf.us  Wed Jul 15 12:44:53 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 15 Jul 2009 09:44:53 -0700
Subject: convert Dbase (.dbf) files to SQLite databases
In-Reply-To: <419cc0e0-3a78-4906-8420-c12ce2684bef@c36g2000yqn.googlegroups.com>
References: <7c5n8kF25pc8bU1@mid.dfncis.de>	<mailman.3145.1247654594.8015.python-list@python.org>
	<419cc0e0-3a78-4906-8420-c12ce2684bef@c36g2000yqn.googlegroups.com>
Message-ID: <4A5E0785.8060307@stoneleaf.us>

John Machin wrote:

> If dbfpy can't handle any new-fangled stuff you may have in your
> files, drop me a line ... I have a soon-to-be released DBF module that
> should be able to read the "new" stuff up to dBase7 and VFP9,
> including memo files, conversion from whatever to Unicode if
> needed, ...
> 
> Cheers,
> John

Cool!  I'm looking forward to it!

~Ethan~


From motoom at xs4all.nl  Wed Jul 15 12:47:13 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Wed, 15 Jul 2009 18:47:13 +0200
Subject: Python Equivalent for dd & fold
In-Reply-To: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
Message-ID: <4A5E0811.2050800@xs4all.nl>

seldan24 wrote:

> what can I use as the equivalent for the Unix 'fold' command?

def fold(s,len):
     while s:
         print s[:len]
         s=s[len:]

s="A very long string indeed. Really that long? Indeed."
fold(s,10)

Output:

A very lon
g string i
ndeed. Rea
lly that l
ong? Indee
d.

Greetings,

-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From weafon at lbl.gov  Wed Jul 15 12:48:49 2009
From: weafon at lbl.gov (weafon)
Date: Wed, 15 Jul 2009 09:48:49 -0700
Subject: How to keep a function as a generator function when the yield
	operator	is moved into its sub-functions??
In-Reply-To: <4A5D4DC5.1090202@ieee.org>
References: <4A5CC86A.9070907@lbl.gov> <4A5D4DC5.1090202@ieee.org>
Message-ID: <4A5E0871.90105@lbl.gov>

Hi DaveA,

Thank for your responses even though my problem has been solved based on 
Miles' suggestion. I am writing programs by using the SimPy library, 
which is a discrete-event simulator library. Below is my actual code segment

class RAID(Process):
    def ReqServ(self):
        while(now()<TM_End):
            yield get, self, self.queue, 1
            orig_req=self.got[0]
            ....
            for devno in range (5):
                ...
                #---- Segment A begins
               new_loc= calcfunc(orig_req.loc)
               new_len= calcfunc(orig_req.len)
               new_req1=   Req(self.cn_req, new_loc, new_len)
               yield put, self, self.disks[devno].queue,[new_req]
               self.cn_req+=1
               new_req2=   Req(self.cn_req, new_loc, new_len)
               yield put, self, self.disks[devno+5].queue,[new_req]
               self.cn_req+=1
               #--- Segment A ends
               ...

In the above example, ReqServ may pause at three lines of yield and 
return something. However, if I move the code segment A into a second 
function as following, then ReqServ will not pause and return things 
back to its caller after calling SegmentA().

class RAID(Process):
    def ReqServ(self):
        while(now()<TM_End):
            yield get, self, self.queue, 1
            orig_req=self.got[0]
            ....
            for devno in range (5):
                ...
                self.SegmentA(orig_req.loc,orig_req.len)
                ...

    def SegmentA(self,loc,len):
        new_loc= calcfunc(loc)
        new_len= calcfunc(len)
        new_req1=   Req(self.cn_req, new_loc, new_len)
        yield put, self, self.disks[devno].queue,[new_req]
        self.cn_req+=1
        new_req2=   Req(self.cn_req, new_loc, new_len)
        yield put, self, self.disks[devno+5].queue,[new_req]
        self.cn_req+=1

Based on Miles's suggestion, we can solve the problem by using 'return' 
in SegmentA() and keeping 'yield' in ReqServ(). For example,

class RAID(Process):
    def ReqServ(self):
        while(now()<TM_End):
            yield get, self, self.queue, 1
            orig_req=self.got[0]
            ....
            for devno in range (5):
                ...
                yield self.SegmentA(orig_req.loc,orig_req.len,0)
                yield self.SegmentA(orig_req.loc,orig_req.len,5)
                ...

    def SegmentA(self,loc,len,shiftno):
        new_loc= calcfunc(loc)
        new_len= calcfunc(len)
        new_req=   Req(self.cn_req, new_loc, new_len)
        self.cn_req+=1
        return put, self, self.disks[devno+shiftno].queue,[new_req]


Regards,
Weafon

Dave Angel wrote:
> weafon wrote:
>> <div class="moz-text-flowed" style="font-family: -moz-fixed">Hi guys,
>>
>> I have a question about the usage of yield. As shown in the below 
>> example, in general, if there is a code segment commonly used by two 
>> or more functions, we may isolate the segment into a function and 
>> then call it from other functions if necessary.
>>
>> def func1():
>>    ....
>>    while(cond):
>>        .....
>>        commoncode()
>>        ...
>>
>>
>> def func2():
>>    ....
>>    while(cond):
>>        .....
>>        commoncode()
>>        ...
>>
>> def commoncode()
>>    AAAA
>>    BBBB
>>    CCCC
>>
>> However, if there is a 'yield' operation in the common code segment, 
>> the isolation causes that func1 and func2 become a non-generator 
>> function!! Although I can prevent such an isolation by just 
>> duplicating the segment in func1 and func2 to keep both of them being 
>> generator functions, the code may become ugly and hard to maintain 
>> particularly when coomoncode() is long.
>>
>> The problem may be resolved if I can define the commoncode() as an 
>> inline function or marco. Unfortunately, inline and marco do not 
>> seems to be implemented in python. Thus, how can I isolate a common 
>> segment into a function when there are yield operations in the common 
>> segment?
>>
>> Thanks,
>> Weafon
>>
> You are implying there's something special or unique about yield in 
> this.  Return has the same problem, and many other flow control 
> constructs.   Also, variable definitions and scoping.
>
> So you can't just copy any old bunch of adjacent lines out of two 
> functions, put it into a third, and call it factoring.  Give us a 
> specific example you're puzzled about, and we can try to solve it.
>
> DaveA
>



From seldan24 at gmail.com  Wed Jul 15 13:14:54 2009
From: seldan24 at gmail.com (seldan24)
Date: Wed, 15 Jul 2009 10:14:54 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
Message-ID: <e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>

On Jul 15, 12:47?pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> seldan24 wrote:
> > what can I use as the equivalent for the Unix 'fold' command?
>
> def fold(s,len):
> ? ? ?while s:
> ? ? ? ? ?print s[:len]
> ? ? ? ? ?s=s[len:]
>
> s="A very long string indeed. Really that long? Indeed."
> fold(s,10)
>
> Output:
>
> A very lon
> g string i
> ndeed. Rea
> lly that l
> ong? Indee
> d.
>
> Greetings,
>
> --
> "The ability of the OSS process to collect and harness
> the collective IQ of thousands of individuals across
> the Internet is simply amazing." - Vinod Valloppillilhttp://www.catb.org/~esr/halloween/halloween4.html

Wow, I feel like a dork.  I should have done more research prior to
posting.  Anyway, thanks for the advice.  The trouble with Python is
that things make 'too much' sense.  Loving this language.


From python at mrabarnett.plus.com  Wed Jul 15 13:23:14 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 15 Jul 2009 18:23:14 +0100
Subject: Python Equivalent for dd & fold
In-Reply-To: <e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
Message-ID: <4A5E1082.8090901@mrabarnett.plus.com>

seldan24 wrote:
> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>> seldan24 wrote:
>>> what can I use as the equivalent for the Unix 'fold' command?
>> def fold(s,len):
>>      while s:
>>          print s[:len]
>>          s=s[len:]
>>
>> s="A very long string indeed. Really that long? Indeed."
>> fold(s,10)
>>
>> Output:
>>
>> A very lon
>> g string i
>> ndeed. Rea
>> lly that l
>> ong? Indee
>> d.
>>
> 
> Wow, I feel like a dork.  I should have done more research prior to
> posting.  Anyway, thanks for the advice.  The trouble with Python is
> that things make 'too much' sense.  Loving this language.

You might still need to tweak the above code as regards how line endings
are handled.


From http  Wed Jul 15 13:25:25 2009
From: http (Paul Rubin)
Date: 15 Jul 2009 10:25:25 -0700
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <7x4otdeu4a.fsf@ruckus.brouhaha.com>

Hrvoje Niksic <hniksic at xemacs.org> writes:
> > While everyone's trying to tell the OP how to workaround the missing
> > xor operator, nobody answered the question "why is there no [boolean]
> > xor operator ?".
> 
> Probably because there isn't one in C.  The bitwise XOR operator, on the
> other hand, exists in both C and Python.

A non-bitwise XOR really sounds almost useless.


From wbrehaut at mcsnet.ca  Wed Jul 15 13:36:21 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 11:36:21 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<mailman.3119.1247612922.8015.python-list@python.org>
	<522e004c-77fc-445f-8951-ad54a0e664d4@d32g2000yqh.googlegroups.com>
	<mailman.3152.1247657854.8015.python-list@python.org>
Message-ID: <id4s55t1sgco9gr3l61d308jg5gj06rhp1@4ax.com>

On Wed, 15 Jul 2009 13:37:22 +0200, Christian Heimes
<lists at cheimes.de> wrote:

>pdpi wrote:
>> On Jul 15, 12:08 am, Christian Heimes <li... at cheimes.de> wrote:
>>> Chris Rebert wrote:
>>>> Using the xor bitwise operator is also an option:
>>>> bool(x) ^ bool(y)
>>> I prefer something like:
>>>
>>>     bool(a) + bool(b) == 1
>>>
>>> It works even for multiple tests (super xor):
>>>
>>>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>>>       raise ValueError("Exactly one of a, b, c and d must be true")
>>>
>>> Christian
>> 
>> "if bool(a) + bool(b) + bool(c) + bool(d) != 1:" is not equivalent to
>> xor. 1 xor 1 xor 1 = 1 xor (1 xor 1) = 1 xor 0 = 1 (or = (1 xor 1) xor
>> 1 = 0 xor 1 = 1 if you assicate to the left)
>
>I'm well aware of the fact that I've described something differently.
>'xor' can be explained as 'check if exactly one element of two elements
>is true'. My algorithms describes a super xor, aka 'check if exactly one
>element of n elements is true'.

But that's not a "super xor" (commonly known as XOR). Rather than
describing xor as:

	check if exactly one element of two elements is true

describe it as:

	check if an odd number of two elements is true

then you'll get the correct definition of "super xor":

	check if an odd number of n elements is true

I.e., XOR determines parity, and:

	XOR <some binary vector v> =
		0 if v has an even number of 1s and 
		1 if v has an odd number of 1s

wayne

>Christian


From jeanmichel at sequans.com  Wed Jul 15 13:43:20 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 19:43:20 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <87fxcxj54d.fsf@busola.homelinux.net>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <4A5E1538.7030107@sequans.com>

Hrvoje Niksic wrote:
[snip]
> Note that in Python A or B is in fact not equivalent to not(not A and
> not B).
>   
 >>> l = [(True, True), (True, False), (False, True), (False, False)]
 >>> for p in l:
...     p[0] or p[1]
...
True
True
True
False
 >>> for p in l:
...     not(not p[0] and not p[1])
...
True
True
True
False
 >>>      

Did I make twice the same obvious error ?

JM


From emile at fenx.com  Wed Jul 15 13:48:42 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 15 Jul 2009 10:48:42 -0700
Subject: Python Equivalent for dd & fold
In-Reply-To: <4A5E1082.8090901@mrabarnett.plus.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
Message-ID: <h3l4kc$57c$1@ger.gmane.org>

On 7/15/2009 10:23 AM MRAB said...
>> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>>> seldan24 wrote:
>>>> what can I use as the equivalent for the Unix 'fold' command?
>>> def fold(s,len):
>>>      while s:
>>>          print s[:len]
>>>          s=s[len:]
>>>
<snip>
> You might still need to tweak the above code as regards how line endings
> are handled.

You might also want to tweak it if the strings are _really_ long to 
simply slice out the substrings as opposed to reassigning the balance to 
a newly created s on each iteration.

Emile



From emile at fenx.com  Wed Jul 15 13:55:22 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 15 Jul 2009 10:55:22 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5E1538.7030107@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
Message-ID: <h3l50s$71e$1@ger.gmane.org>

On 7/15/2009 10:43 AM Jean-Michel Pichavant said...
> Hrvoje Niksic wrote:
> [snip]
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>>   
>  >>> l = [(True, True), (True, False), (False, True), (False, False)]
>  >>> for p in l:
> ...     p[0] or p[1]
> ...
> True
> True
> True
> False
>  >>> for p in l:
> ...     not(not p[0] and not p[1])
> ...
> True
> True
> True
> False
>  >>>     
> Did I make twice the same obvious error ?

No -- but in the not(not... example it doesn't short-circuit.

Emile



From rodriguealcazar at gmail.com  Wed Jul 15 13:55:34 2009
From: rodriguealcazar at gmail.com (Rodrigue)
Date: Wed, 15 Jul 2009 10:55:34 -0700 (PDT)
Subject: python first assignment of a global variable
Message-ID: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>

Hi all,

I came accross a strange behaviour in python today. Here is a simple
example to describe my situation:

MY_GLOBAL = ''

def a():
    print 'global is: ', MY_GLOBAL

def b():
    try:
        MY_GLOBAL += 'bla'
    except Exception, e:
        print 'b: ', e

def c():
    try:
        global MY_GLOBAL
        MY_GLOBAL += 'bla'
    except Exception, e:
        print 'c: ', e

def d():
    try:
        if not MY_GLOBAL:
            print 'not my global'
    except Exception, e:
        print 'd: ', e

def e():
    try:
        if not MY_GLOBAL:
            MY_GLOBAL = ''
    except Exception, e:
        print 'e: ', e

def f():
    global MY_GLOBAL
    if not MY_GLOBAL:
        MY_GLOBAL = ''

def e_raise():
    if not MY_GLOBAL:
        MY_GLOBAL = 'bla'

if __name__ == "__main__":
    a()
    b()
    c()
    d()
    e()
    f()
    e_raise()


And here is the output I get:

global is:
b:  local variable 'MY_GLOBAL' referenced before assignment
e:  local variable 'MY_GLOBAL' referenced before assignment
Traceback (most recent call last):
  File "glo.py", line 49, in <module>
    e_raise()
  File "glo.py", line 39, in e_raise
    if not MY_GLOBAL:
UnboundLocalError: local variable 'MY_GLOBAL' referenced before
assignment


Now, I was reading that page http://stackoverflow.com/questions/370357/python-variable-scope-question
and found (understood) only part of the behaviour that could explain
the output.

Basically, I was very surprised to discover that e() raises an
exception, but even more that e_raise() points to
if not MY_GLOBAL Is the problem not really when I assign?

My assumption is that some reordering is happening behind the scenes
that creates a situation similar to the += which assigns hence expects
to be at the local level.

I would love some enlightenment here

Rodrigue


From milesck at umich.edu  Wed Jul 15 13:57:20 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 13:57:20 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5E1538.7030107@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
Message-ID: <ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>


On Jul 15, 2009, at 1:43 PM, Jean-Michel Pichavant wrote:

> Hrvoje Niksic wrote:
> [snip]
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>>
> >>> l = [(True, True), (True, False), (False, True), (False, False)]
> >>> for p in l:
> ...     p[0] or p[1]
> [snip]
> Did I make twice the same obvious error ?


Try again with:

l = [('foo','bar'), ('foo', ''), ('', 'bar'), ('', '')]

-Miles



From milesck at umich.edu  Wed Jul 15 14:10:50 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 14:10:50 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3l50s$71e$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com> <h3l50s$71e$1@ger.gmane.org>
Message-ID: <D7CCEA0C-2AAC-473D-9081-2EE690D82BC7@umich.edu>

On Jul 15, 2009, at 1:55 PM, Emile van Sebille wrote:
> On 7/15/2009 10:43 AM Jean-Michel Pichavant said...
>> Hrvoje Niksic wrote:
>> [snip]
>>> Note that in Python A or B is in fact not equivalent to not(not A  
>>> and
>>> not B).
>>>
>> Did I make twice the same obvious error ?
>
> No -- but in the not(not... example it doesn't short-circuit.

No; like 'A or B', 'not (not A and not B)' does in fact short-circuit  
if A is True.  (The 'and' condition does not have to evaluate the  
right operand when 'not A' is False.)

-Miles



From tjreedy at udel.edu  Wed Jul 15 14:14:55 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 15 Jul 2009 14:14:55 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5DA247.3040606@timgolden.me.uk>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<4A5DA247.3040606@timgolden.me.uk>
Message-ID: <h3l6at$bjd$1@ger.gmane.org>

Tim Golden wrote:

> I was pondering on this yesterday, and the only case I've
> come across in my code -- and it's reasonably common --
> is checking that one and only one of two params has been
> passed. I have code which wants, say, an id or a name
> but doesn't want both. It's hardly difficult to write the
> check even now, but an built-in xor would make it fractionally
> cleaner.

I think I would just have one parameter id_name or identifier so no 
check is needed. This is a common idiom in Python where names are not 
typed. Example: param 'source' is a string (with a file name to be 
opened) or an already opened file. If you want two local vars inside the 
function, that should be kept private to the function.

tjr



From emile at fenx.com  Wed Jul 15 14:14:57 2009
From: emile at fenx.com (Emile van Sebille)
Date: Wed, 15 Jul 2009 11:14:57 -0700
Subject: python first assignment of a global variable
In-Reply-To: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
References: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
Message-ID: <h3l65k$b4q$1@ger.gmane.org>

On 7/15/2009 10:55 AM Rodrigue said...
> I came accross a strange behaviour in python today. Here is a simple
> example to describe my situation:
> 
> MY_GLOBAL = ''

<snip>

> def e_raise():
>     if not MY_GLOBAL:
>         MY_GLOBAL = 'bla'
> 

<snip>

> Traceback (most recent call last):
>   File "glo.py", line 49, in <module>
>     e_raise()
>   File "glo.py", line 39, in e_raise
>     if not MY_GLOBAL:
> UnboundLocalError: local variable 'MY_GLOBAL' referenced before
> assignment

the def prepares the function for subsequent use.  At this prep time, 
MY_GLOBAL, by virtue of being assigned to later in the function, and the 
absence of a global statement, is identified as a local variable. 
Later, at execution time, testing MY_GLOBAL fails as it's not yet been 
assigned to.

HTH,

Emile



From milesck at umich.edu  Wed Jul 15 14:17:27 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 14:17:27 -0400
Subject: python first assignment of a global variable
In-Reply-To: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
References: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
Message-ID: <4C9A140E-7BAB-49F5-97B7-FAD86DD0E2CF@umich.edu>

On Jul 15, 2009, at 1:55 PM, Rodrigue wrote:

> Basically, I was very surprised to discover that e() raises an
> exception, but even more that e_raise() points to
> if not MY_GLOBAL Is the problem not really when I assign?
>
> My assumption is that some reordering is happening behind the scenes
> that creates a situation similar to the += which assigns hence expects
> to be at the local level.

The determination of whether a name is a reference to a local or  
global variable is made at compile time.  When a function contains a  
single assignment (or augmented assignment) to a name, the compiler  
generates bytecode such that all references to that name within the  
function will be looked up in the local scope only, including those  
before the assignment statement.

-Miles



From pfeldman at verizon.net  Wed Jul 15 14:19:18 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Wed, 15 Jul 2009 11:19:18 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>
References: <24485116.post@talk.nabble.com>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<24486661.post@talk.nabble.com> <h3irjm$ro$1@ger.gmane.org>
	<4A5CFAC4.7020300@stoneleaf.us>
	<4A5CFF83.9070301@mrabarnett.plus.com>
	<0bcb7d71-6740-497a-bcf2-6139ea0c64ab@o15g2000yqm.googlegroups.com>
Message-ID: <24503248.post@talk.nabble.com>


I did initially ask for an infix xor operator, but eventually gave up on
this.  I like the first of your two one-line solutions below; this is clean
and easy to understand.  Thanks!  I'd still like to be able to write an
expression like '(a and b) xor (c and d) xor (e and f)', but it looks as
though that can't be done.



<snip>

Well, that's not exactly what you originally asked for.  But it's
still a one-liner:

def xor(*args): return bool(sum(map(bool, args)) % 2)

or perhaps

def xor(*args): return bool(len(filter(None, args)) & 1)
-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24503248.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From milesck at umich.edu  Wed Jul 15 14:24:23 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 15 Jul 2009 14:24:23 -0400
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <m2prc3dlfo.fsf@valheru.db3l.homeip.net>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<m2prc3dlfo.fsf@valheru.db3l.homeip.net>
Message-ID: <B6A1B5F7-BA59-4B8A-A039-7D1CF93CEF39@umich.edu>

On Jul 14, 2009, at 5:06 PM, David Bolen wrote:
> Are you sure?  It seems to restrict them in the same block, but not in
> the entire file.  At least I was able to use both space and tab
> indented blocks in the same file with Python 3.0 and 3.1.

It seems to me that, within an indented block, Python 3.1 requires  
that you are consistent in your use of indentation characters *for  
that indentation level*.  For example, the following code seems to be  
allowed:

def foo():
<TAB>if True:
<TAB><SP><SP>x = 1
<TAB>else:
<TAB><TAB>x = 2
<TAB>return x

But replacing any of the first tabs on each line with 8 spaces  
(without replacing them all), which previously would have been  
allowed, is now an error.

-Miles



From wbrehaut at mcsnet.ca  Wed Jul 15 14:29:54 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 12:29:54 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>

On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson
<dickinsm at gmail.com> wrote:

>On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
>wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
>> have an 'xor' operator as well.
>
>Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
>that it's sufficiently useful to justify adding a new keyword 'xor' to
>the language;  I suspect that would be an uphill struggle. :)
>
>I'll just note that:
>
>(1) It's easy to emulate xor:  'x xor y' <-> bool(x) != bool(y)
>
>(2) 'and' and 'or' are special in that they have useful short-
>circuiting behaviour; xor doesn't have this property (that is, you
>always need to evaluate *both* operands to determine the result).
>
>I'd also guess that 'xor' would be much less used than 'and' or 'or',
>but maybe that's just a reflection of the sort of code that I tend to
>write.

You're right about that!. It's used everywhere in:

- coding and encryption theory (and practice) (e.g.,
http://www.mathcs.emory.edu/~whalen/Hash/Hash_Articles/IEEE/XOR-based%20hash%20functions.pdf)
- emulation and simulation of hardware (since all but the most trivial
logic circuits are likely to include XOR-gates)
- hence, for design of new architectures or simulators or virtual
machines and simplification of existing ones--(e.g.,
http://www.date-conference.com/archive/conference/proceedings/PAPERS/1999/DATE99/PDFFILES/05A_6.PDF)
and
http://bochs.sourceforge.net/Virtualization_Without_Hardware_Final.pdf
which includes:

"The answer relies on the observation that subtracting an integer
value from 0xFFFFFFFF gives the same result as XOR-ing that same value
to 0xFFFFFFFF."

And, perhaps the most useful use of all, for Bouton's solution of the
game of Nim--both for the proof that his strategy "solves" the game
and for an easy implementation of a Nim-playing program--and the only
operator needed is XOR (e.g., http://www.wordiq.com/definition/Nim).

wayne


From gerard.blais at gmail.com  Wed Jul 15 14:40:32 2009
From: gerard.blais at gmail.com (MCIPERF)
Date: Wed, 15 Jul 2009 11:40:32 -0700 (PDT)
Subject: Catching control-C
References: <0fe9e54d-a8bd-4fca-ac94-addce8c963e9@u16g2000pru.googlegroups.com>
	<mailman.2722.1246916882.8015.python-list@python.org>
	<c382c66b-f5a1-4129-a383-d18496412758@p36g2000prn.googlegroups.com>
	<n8m5m.3759$ze1.2493@news-server.bigpond.net.au>
	<mailman.2920.1247182102.8015.python-list@python.org>
Message-ID: <a27f8bda-55bd-4d71-87ff-af6ac07fcd75@r24g2000vbn.googlegroups.com>

On Jul 9, 7:28?pm, Miles Kaufmann <mile... at umich.edu> wrote:
> On Jul 9, 2009, at 9:20 AM, Lie Ryan wrote:
>
> > Michael Mossey wrote:
> >> I want to understand better what the "secret" is to responding to a
> >> ctrl-C in any shape or form.
>
> > Are you asking: "when would the python interpreter process
> > KeyboardInterrupt?"
> > ...
> > In single threaded python program, the currently running thread is
> > always the main thread (which can handle KeyboardInterrupt). I believe
> > SIGINT is checked at every ticks. But SIGINT cannot interrupt atomic
> > operations (i.e. it cannot interrupt long operations that takes a ?
> > single
> > tick).
>
> Some otherwise atomic single-bytecode operations (like large integer ?
> arithmetic) do manual checks for whether signals were raised (though ?
> that won't help at all if the operation isn't on the main thread).
>
> > I believe a tick in python is equivalent to a single bytecode, but
> > please correct me if I'm wrong.
>
> Not all opcodes qualify as a tick. ?In general, those opcodes that ?
> cause control to remain in the eval loop (and not make calls to other ?
> Python or C functions) don't qualify as ticks (but there are ?
> exceptions, e.g. so that while True: pass is interruptible). ?In ?
> Python/ceval.c: PyEval_EvalFrameEx(), those opcodes that don't end in ?
> goto fast_next_opcode are ticks.
>
> Please correct me if _I'm_ wrong! :)
> -Miles

You don't need to do I/O.

This works:

try:
   process_forever()
except KeyboardInterrupt:
   save critical stuff
   write nice messages

I often wrap a large computational task like this, with the idea that
the exception can let me exit safely, in my case by writing restart
parameters and printing a summary pf progress to date.

Gerry


From amrita at iisermohali.ac.in  Wed Jul 15 14:46:29 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Thu, 16 Jul 2009 00:16:29 +0530 (IST)
Subject: mail
Message-ID: <7683.210.212.36.65.1247683589.squirrel@www.iisermohali.ac.in>


Dear all,

Sorry that I am disturbing you all again and again but this is the way I
am trying to solve my problem:---

>>> import re
>>> exp = re.compile("CA")
>>> infile = open("file1.txt")
>>> for line in infile:
...     values = re.split("\s+", line)
...     if exp.search(line):
...        print ("%s %s CA = %s" %(values[2], values[3], values[6]))
...
 with this it is giving the output like:----

8 ALA CA = 54.67
15 ALA CA = 52.18
21 ALA CA = 54.33
23 ALA CA = 55.84
33 ALA CA = 55.58
38 ALA CA = 54.33

which is all right but i want CB and C value also in each row and it
should take value from 5th column infront of them, file is something
lookin like:-----

 47     8   ALA       H     H      7.85     0.02     1
 48     8   ALA       HA    H      2.98     0.02     1
 49     8   ALA       HB    H      1.05     0.02     1
 50     8   ALA       C     C    179.39      0.3     1
 51     8   ALA       CA    C     54.67      0.3     1
 52     8   ALA       CB    C     18.85      0.3     1
 53     8   ALA       N     N    123.95      0.3     1
107    15   ALA       H     H      8.05     0.02     1
108    15   ALA       HA    H      4.52     0.02     1
109    15   ALA       HB    H      1.29     0.02     1
110    15   ALA       C     C    177.18      0.3     1
111    15   ALA       CA    C     52.18      0.3     1
112    15   ALA       CB    C     20.64      0.3     1
113    15   ALA       N     N    119.31      0.3     1
154    21   ALA       H     H      7.66     0.02     1
155    21   ALA       HA    H      4.05     0.02     1
156    21   ALA       HB    H      1.39     0.02     1
157    21   ALA       C     C    179.35      0.3     1
158    21   ALA       CA    C     54.33      0.3     1
159    21   ALA       CB    C     17.87      0.3     1
160    21   ALA       N     N    123.58      0.3     1
169    23   ALA       H     H      8.78     0.02     1
170    23   ALA       HA    H      4.14     0.02     1
171    23   ALA       HB    H      1.62     0.02     1
172    23   ALA       C     C    179.93      0.3     1
173    23   ALA       CA    C     55.84      0.3     1
174    23   ALA       CB    C     17.55      0.3     1
175    23   ALA       N     N    120.16      0.3     1
232    33   ALA       H     H      7.57     0.02     1
233    33   ALA       HA    H      3.89     0.02     1
234    33   ALA       HB    H      1.78     0.02     1
235    33   ALA       C     C    179.24      0.3     1
236    33   ALA       CA    C     55.58      0.3     1
237    33   ALA       CB    C     19.75      0.3     1
238    33   ALA       N     N    121.52      0.3     1
269    38   ALA       H     H      8.29     0.02     1
270    38   ALA       HA    H      4.04     0.02     1
271    38   ALA       HB    H      1.35     0.02     1
272    38   ALA       C     C    178.95      0.3     1
273    38   ALA       CA    C     54.33      0.3     1
274    38   ALA       CB    C     18.30      0.3     1
275    38   ALA       N     N    120.62      0.3     1

I just want that it will give output something like:-----

8  ALA  C = 179.39  CA = 54.67  CB = 18.85
15 ALA  C = 177.18  CA = 52.18  CB = 20.64
21 ALA  C = 179.35  CA = 54.33  CB = 17.87.....

so first it will write the position of the amino acid(given by second
column)then amino acid here it is ALA and then the corresponding value of
C, CA and CB from 5th colum for each position of ALA.




Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From robert.kern at gmail.com  Wed Jul 15 14:47:28 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 15 Jul 2009 13:47:28 -0500
Subject: missing 'xor' Boolean operator
In-Reply-To: <tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
Message-ID: <h3l881$h4b$1@ger.gmane.org>

On 2009-07-15 13:29, Wayne Brehaut wrote:
> On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson
> <dickinsm at gmail.com>  wrote:
>
>> On Jul 14, 7:25 pm, "Dr. Phillip M. Feldman"<pfeld... at verizon.net>
>> wrote:
>>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice to
>>> have an 'xor' operator as well.
>> Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
>> that it's sufficiently useful to justify adding a new keyword 'xor' to
>> the language;  I suspect that would be an uphill struggle. :)
>>
>> I'll just note that:
>>
>> (1) It's easy to emulate xor:  'x xor y'<->  bool(x) != bool(y)
>>
>> (2) 'and' and 'or' are special in that they have useful short-
>> circuiting behaviour; xor doesn't have this property (that is, you
>> always need to evaluate *both* operands to determine the result).
>>
>> I'd also guess that 'xor' would be much less used than 'and' or 'or',
>> but maybe that's just a reflection of the sort of code that I tend to
>> write.
>
> You're right about that!. It's used everywhere in:
>
> - coding and encryption theory (and practice) (e.g.,
> http://www.mathcs.emory.edu/~whalen/Hash/Hash_Articles/IEEE/XOR-based%20hash%20functions.pdf)
> - emulation and simulation of hardware (since all but the most trivial
> logic circuits are likely to include XOR-gates)
> - hence, for design of new architectures or simulators or virtual
> machines and simplification of existing ones--(e.g.,
> http://www.date-conference.com/archive/conference/proceedings/PAPERS/1999/DATE99/PDFFILES/05A_6.PDF)
> and
> http://bochs.sourceforge.net/Virtualization_Without_Hardware_Final.pdf
> which includes:
>
> "The answer relies on the observation that subtracting an integer
> value from 0xFFFFFFFF gives the same result as XOR-ing that same value
> to 0xFFFFFFFF."
>
> And, perhaps the most useful use of all, for Bouton's solution of the
> game of Nim--both for the proof that his strategy "solves" the game
> and for an easy implementation of a Nim-playing program--and the only
> operator needed is XOR (e.g., http://www.wordiq.com/definition/Nim).

All of those can use the bitwise XOR operator, not the boolean XOR. Python 
already has the ^ operator for those purposes.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dickinsm at gmail.com  Wed Jul 15 14:51:44 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Wed, 15 Jul 2009 11:51:44 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
Message-ID: <d5c62721-6d07-415f-b2de-150584504608@i6g2000yqj.googlegroups.com>

On Jul 15, 7:29?pm, Wayne Brehaut <wbreh... at mcsnet.ca> wrote:
> On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson <dicki... at gmail.com> wrote:
> >I'd also guess that 'xor' would be much less used than 'and' or 'or',
> >but maybe that's just a reflection of the sort of code that I tend to
> >write.
>
> You're right about that!. It's used everywhere in:
> [snip examples and references]

Those examples are (almost) all about the *bitwise* xor operator,
which exists in Python ('^') and, as you point out, has no shortage of
good uses.  The discussion was about a *logical* xor, to parallel the
existing 'and' and 'or' operators.

--
Mark


From anthony.tolle at gmail.com  Wed Jul 15 14:53:23 2009
From: anthony.tolle at gmail.com (Anthony Tolle)
Date: Wed, 15 Jul 2009 11:53:23 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
Message-ID: <ae7da03e-5852-4dbe-b11c-37f4afc32dbe@n11g2000yqb.googlegroups.com>

On Jul 14, 2:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
> have an 'xor' operator as well.

My $0.02 on this discussion: There would be nothing gained by having
non-bitwise XOR operator.  You can't short-circuit XOR, because you
must evaluate all operands to produce a result.  Consequently,
returning the "true" item also doesn't make much sense.  XOR is closer
to the the logical NOT operator than it is to AND or OR.

Here's my own take on a function that can handle any number of
arguments (it should probably raise an exception for 0 or 1 arguments,
but I'm lazy):

def xor(*operands):
    if operands:
        operands = list(operands)
        a = bool(operands.pop(0))
        while operands:
            b = bool(operands.pop(0))
            if a:
                if b:
                    a = False
            elif b:
                a = True
        return a
    return False


From jeanmichel at sequans.com  Wed Jul 15 15:05:16 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 15 Jul 2009 21:05:16 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
Message-ID: <4A5E286C.5060607@sequans.com>

Miles Kaufmann wrote:
>
> On Jul 15, 2009, at 1:43 PM, Jean-Michel Pichavant wrote:
>
>> Hrvoje Niksic wrote:
>> [snip]
>>> Note that in Python A or B is in fact not equivalent to not(not A and
>>> not B).
>>>
>> >>> l = [(True, True), (True, False), (False, True), (False, False)]
>> >>> for p in l:
>> ...     p[0] or p[1]
>> [snip]
>> Did I make twice the same obvious error ?
>
>
> Try again with:
>
> l = [('foo','bar'), ('foo', ''), ('', 'bar'), ('', '')]
>
> -Miles
>
Didn't know that.
So if I resume:
- not 'foo' => False
- 'foo' or 'foo' => 'foo'

I may be missing something, but honestly, Guido must have smoked some 
heavy stuff to write such logic, has he ?

Let's play again
False or 'foo' => 'foo'
False and 'foo' => False

So funny. I would have expected boolean operators to return a boolean 
value. I should have read the f*** manual (this is an anticipated RTFM 
counter-attack). Anyway Miles, thanks for the update.

JM



From invalid at invalid  Wed Jul 15 15:05:30 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 15 Jul 2009 14:05:30 -0500
Subject: mail
References: <mailman.3184.1247683595.8015.python-list@python.org>
Message-ID: <zeydnTuRPNnntcPXnZ2dnUVZ_t6dnZ2d@posted.visi>

On 2009-07-15, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:

> Sorry that I am disturbing you all again and again but this is the way I
> am trying to solve my problem:---

We could probably be a lot more helpful if you would keep these
postings all in a single thread so that people who didn't read
the first postings knew what you were talking about in
subsequent postings.


>>>> import re
>>>> exp = re.compile("CA")

> [...]
>
> file is something lookin like:-----
>
>  47     8   ALA       H     H      7.85     0.02     1

[...]

IMO you're making a mistake using the "re" module for this
task.  I think you'd be a lot better off if you just used the
string type's split method to split each line up into fields
and processed the individual fields:

  for line in inputfile:
  
      field = line.split()

      if field[2] == "CA":
         <<do whatever with whichever fields you care about>>
      elif field[2] == "soemthing-else"
         <<do something else with some other fields>>      

  <<print results of doing whatever and something else above>>

-- 
Grant Edwards                   grante             Yow! If I felt any more
                                  at               SOPHISTICATED I would DIE
                               visi.com            of EMBARRASSMENT!


From jcd at sdf.lonestar.org  Wed Jul 15 15:40:36 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Wed, 15 Jul 2009 15:40:36 -0400
Subject: mail
In-Reply-To: <7683.210.212.36.65.1247683589.squirrel@www.iisermohali.ac.in>
References: <7683.210.212.36.65.1247683589.squirrel@www.iisermohali.ac.in>
Message-ID: <1247686836.11677.196.camel@aalcdl07>

On Thu, 2009-07-16 at 00:16 +0530, amrita at iisermohali.ac.in wrote:
> Dear all,
> 
> Sorry that I am disturbing you all again and again but this is the way I
> am trying to solve my problem:---
> 
> >>> import re
> >>> exp = re.compile("CA")
> >>> infile = open("file1.txt")
> >>> for line in infile:
> ...     values = re.split("\s+", line)
> ...     if exp.search(line):
> ...        print ("%s %s CA = %s" %(values[2], values[3], values[6]))
> ...
>  with this it is giving the output like:----
> 
> 8 ALA CA = 54.67
> 15 ALA CA = 52.18
> 21 ALA CA = 54.33
> 23 ALA CA = 55.84
> 33 ALA CA = 55.58
> 38 ALA CA = 54.33
> 
> which is all right but i want CB and C value also in each row and it
> should take value from 5th column infront of them, file is something
> lookin like:-----
> 
>  47     8   ALA       H     H      7.85     0.02     1
>  48     8   ALA       HA    H      2.98     0.02     1
>  49     8   ALA       HB    H      1.05     0.02     1
>  50     8   ALA       C     C    179.39      0.3     1
>  51     8   ALA       CA    C     54.67      0.3     1
>  52     8   ALA       CB    C     18.85      0.3     1
>  53     8   ALA       N     N    123.95      0.3     1
> 107    15   ALA       H     H      8.05     0.02     1
> 108    15   ALA       HA    H      4.52     0.02     1
> 109    15   ALA       HB    H      1.29     0.02     1
> 110    15   ALA       C     C    177.18      0.3     1
> 111    15   ALA       CA    C     52.18      0.3     1
> 112    15   ALA       CB    C     20.64      0.3     1
> 113    15   ALA       N     N    119.31      0.3     1
> 154    21   ALA       H     H      7.66     0.02     1
> 155    21   ALA       HA    H      4.05     0.02     1
> 156    21   ALA       HB    H      1.39     0.02     1
> 157    21   ALA       C     C    179.35      0.3     1
> 158    21   ALA       CA    C     54.33      0.3     1
> 159    21   ALA       CB    C     17.87      0.3     1
> 160    21   ALA       N     N    123.58      0.3     1
> 169    23   ALA       H     H      8.78     0.02     1
> 170    23   ALA       HA    H      4.14     0.02     1
> 171    23   ALA       HB    H      1.62     0.02     1
> 172    23   ALA       C     C    179.93      0.3     1
> 173    23   ALA       CA    C     55.84      0.3     1
> 174    23   ALA       CB    C     17.55      0.3     1
> 175    23   ALA       N     N    120.16      0.3     1
> 232    33   ALA       H     H      7.57     0.02     1
> 233    33   ALA       HA    H      3.89     0.02     1
> 234    33   ALA       HB    H      1.78     0.02     1
> 235    33   ALA       C     C    179.24      0.3     1
> 236    33   ALA       CA    C     55.58      0.3     1
> 237    33   ALA       CB    C     19.75      0.3     1
> 238    33   ALA       N     N    121.52      0.3     1
> 269    38   ALA       H     H      8.29     0.02     1
> 270    38   ALA       HA    H      4.04     0.02     1
> 271    38   ALA       HB    H      1.35     0.02     1
> 272    38   ALA       C     C    178.95      0.3     1
> 273    38   ALA       CA    C     54.33      0.3     1
> 274    38   ALA       CB    C     18.30      0.3     1
> 275    38   ALA       N     N    120.62      0.3     1
> 
> I just want that it will give output something like:-----
> 
> 8  ALA  C = 179.39  CA = 54.67  CB = 18.85
> 15 ALA  C = 177.18  CA = 52.18  CB = 20.64
> 21 ALA  C = 179.35  CA = 54.33  CB = 17.87.....
> 
> so first it will write the position of the amino acid(given by second
> column)then amino acid here it is ALA and then the corresponding value of
> C, CA and CB from 5th colum for each position of ALA.
> 

Your program is structured wrong for doing what you want.  Right now you
are essentially saying, "for each line in the input file, print
something", but each line of the input file only has part of the
information you want.  Instead, you should create a data structure that
gathers the pieces you want, and only print once you have all of those
pieces in place.

Step one, create your data structure, so the data is grouped the way you
want it, not by line:

>>> thingies = {} # create a dictionary
>>> for line in infile:
>>>     data = line.split()
>>>
>>>     if data[1] not in thingies:
>>>         # group data by data[1]
>>>         thingies[data[1]] = {}
>>> 
>>>     thingies[data[1]][data[3]] = data[5]

Step two, extract the data from the list:

>>> for key, data in thingies.items(): 
>>>     print key,
>>>     for entry in data
>>>     print '%s = %s' % (entry, data[entry]),

This should do what you want, minus some formatting issues.

Cheers,
Cliff




From stefan_ml at behnel.de  Wed Jul 15 15:48:13 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Wed, 15 Jul 2009 21:48:13 +0200
Subject: compiling python
In-Reply-To: <mailman.3123.1247616711.8015.python-list@python.org>
References: <mailman.3123.1247616711.8015.python-list@python.org>
Message-ID: <4a5e327d$0$31339$9b4e6d93@newsspool4.arcor-online.net>

Mag Gam wrote:
> At my university we are trying to compile python with --enable-shared

Is there a reason why you need to compile the CPython interpreter yourself?


> however when I do a make many things fail. Is it a good idea to
> compile python with shared libraries?

Perfectly fine, Linux distros do that by default, for example.

"many things fail" is not a very detailed problem description, though.
Could you state more exactly what you do and provide the error messages
that you see?

Stefan


From wbrehaut at mcsnet.ca  Wed Jul 15 15:55:08 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 13:55:08 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<tp5s55t9rg85hsh3rlm1amm7j4pvctq1sj@4ax.com>
	<d5c62721-6d07-415f-b2de-150584504608@i6g2000yqj.googlegroups.com>
Message-ID: <qtbs55hf9u1f2uql70ea9576caelk1q63u@4ax.com>

On Wed, 15 Jul 2009 11:51:44 -0700 (PDT), Mark Dickinson
<dickinsm at gmail.com> wrote:

>On Jul 15, 7:29?pm, Wayne Brehaut <wbreh... at mcsnet.ca> wrote:
>> On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson <dicki... at gmail.com> wrote:
>> >I'd also guess that 'xor' would be much less used than 'and' or 'or',
>> >but maybe that's just a reflection of the sort of code that I tend to
>> >write.
>>
>> You're right about that!. It's used everywhere in:
>> [snip examples and references]
>
>Those examples are (almost) all about the *bitwise* xor operator,
>which exists in Python ('^') and, as you point out, has no shortage of
>good uses.  The discussion was about a *logical* xor, to parallel the
>existing 'and' and 'or' operators.

I thought you were saying your program domains didn't include a lot of
requirements for xor in general, rather than just no uses for Boolean
xor--and I'm used to thinking of xor on binary vectors as "Boolean"
anyway so would still have been confused.

The most common non-binary-bit-wise xor is the general "symmetric
difference" of sets, most likely to be useful in list or dictionary
processing or database-like contexts. Please see my suggested use-case
for Steven below.

wayne


From miheavner at gmail.com  Wed Jul 15 15:55:56 2009
From: miheavner at gmail.com (mheavner)
Date: Wed, 15 Jul 2009 12:55:56 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
Message-ID: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>

I'm using multiprocessing to spawn several subprocesses, each of which
uses a very large data structure (making it impractical to pass it via
pipes / pickling). I need to allocate this structure once when the
process is created and have it remain in memory for the duration of
the process. The way the multiprocessing module is set up, only the
'run' method runs within the subprocess - so creating a wrapper class
with a constructor that allocates the structure in __init__ will not
work, as far as I know, as this will still be within the parent
process.

If I were working in C/C++, I would declare the variable "static"
within the function body - is there any way with the multiprocessing
module to have persistent data members within subprocesses?

Any ideas??

Thanks,
   Matt


From drozzy at gmail.com  Wed Jul 15 16:00:06 2009
From: drozzy at gmail.com (drozzy)
Date: Wed, 15 Jul 2009 13:00:06 -0700 (PDT)
Subject: Reading a large csv file
References: <1cbd6f830906222017m694bc738m40a46e2851381e@mail.gmail.com> 
	<b78ad4bc0906222128h42d498b0xbfa29684391fa1d4@mail.gmail.com> 
	<1cbd6f830906222227q7ec2a89ke3d4805c9ace80e8@mail.gmail.com> 
	<h1pv45$l7h$1@ger.gmane.org> <4A41D1FD.7080004@simplistix.co.uk> 
	<mailman.2048.1245843498.8015.python-list@python.org>
	<pyv0m.524$ze1.126@news-server.bigpond.net.au> 
	<mailman.2155.1246013561.8015.python-list@python.org>
Message-ID: <c4382879-c75b-47e8-b05b-073cba6b90df@l32g2000vbp.googlegroups.com>

On Jun 26, 6:47?am, Mag Gam <magaw... at gmail.com> wrote:
> Thankyou everyone for the responses! I took some of your suggestions
> and my loading sped up by 25%

what a useless post...


From hniksic at xemacs.org  Wed Jul 15 16:00:52 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Wed, 15 Jul 2009 22:00:52 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<mailman.3174.1247679810.8015.python-list@python.org>
Message-ID: <87bpnliumj.fsf@busola.homelinux.net>

Jean-Michel Pichavant <jeanmichel at sequans.com> writes:

> Hrvoje Niksic wrote:
> [snip]
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>>   
>>>> l = [(True, True), (True, False), (False, True), (False, False)]
>>>> for p in l:
> ...     p[0] or p[1]
[...]

Try with a different data set, for example:

>>> 10 or 20
10
>>> not(not 10 and not 20)
True


From deets at nospam.web.de  Wed Jul 15 16:22:46 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 22:22:46 +0200
Subject: Persistent variable in subprocess using multiprocessing?
In-Reply-To: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
Message-ID: <7c6s4nF25vs08U1@mid.uni-berlin.de>

mheavner schrieb:
> I'm using multiprocessing to spawn several subprocesses, each of which
> uses a very large data structure (making it impractical to pass it via
> pipes / pickling). I need to allocate this structure once when the
> process is created and have it remain in memory for the duration of
> the process. The way the multiprocessing module is set up, only the
> 'run' method runs within the subprocess - so creating a wrapper class
> with a constructor that allocates the structure in __init__ will not
> work, as far as I know, as this will still be within the parent
> process.
> 
> If I were working in C/C++, I would declare the variable "static"
> within the function body - is there any way with the multiprocessing
> module to have persistent data members within subprocesses?

Works for me, at least under OSX (and I presume *nixes in general work.) 
No idea about Windows.


The thing to keep in mind is that forking is used, and that 
interpreter-state up to the moment of the fork is the same for all 
subprocesses.



from multiprocessing import Process

class MyProcess(Process):


     def __init__(self, huge_shared_state):
         self.huge_shared_state = huge_shared_state
         super(MyProcess, self).__init__()


     def run(self):
         print self.name, len(self.huge_shared_state)




shared_state = range(1000000)

processes = []
for i in xrange(10):
     p = MyProcess(shared_state)
     p.start()
     processes.append(p)


for p in processes:
     p.join()



Diez


From db3l.net at gmail.com  Wed Jul 15 16:26:17 2009
From: db3l.net at gmail.com (David Bolen)
Date: Wed, 15 Jul 2009 16:26:17 -0400
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<m2prc3dlfo.fsf@valheru.db3l.homeip.net>
	<mailman.3183.1247682273.8015.python-list@python.org>
Message-ID: <m2hbxdelqu.fsf@valheru.db3l.homeip.net>

Miles Kaufmann <milesck at umich.edu> writes:

> On Jul 14, 2009, at 5:06 PM, David Bolen wrote:
>> Are you sure?  It seems to restrict them in the same block, but not in
>> the entire file.  At least I was able to use both space and tab
>> indented blocks in the same file with Python 3.0 and 3.1.
>
> It seems to me that, within an indented block, Python 3.1 requires
> that you are consistent in your use of indentation characters *for
> that indentation level*.  For example, the following code seems to be
> allowed:

Um, right - in other words, what I said :-)

-- David


From rodriguealcazar at gmail.com  Wed Jul 15 16:27:11 2009
From: rodriguealcazar at gmail.com (Rodrigue)
Date: Wed, 15 Jul 2009 13:27:11 -0700 (PDT)
Subject: python first assignment of a global variable
References: <fe6fb3f7-1e44-43f6-a380-f82593a4cbec@o6g2000yqj.googlegroups.com>
	<mailman.3181.1247681857.8015.python-list@python.org>
Message-ID: <47c62f6f-cf9a-4f74-ad71-5f2eccc8c797@h2g2000yqg.googlegroups.com>

> MY_GLOBAL, by virtue of being assigned to later in the function, and the
> absence of a global statement, is identified as a local variable.

> When a function contains a
> single assignment (or augmented assignment) to a name, the compiler
> generates bytecode such that all references to that name within the
> function will be looked up in the local scope only

Alright. I didn't know that. I thought the entire scope (local, then
global) was considered in every situation. It does explain the
observed behaviour then.

I'm surprised I never bumped into that before, but I'm glad I learnt
something new about python today.

Thanks Emile and Miles for the explanation!


From georgeoliverGO at gmail.com  Wed Jul 15 16:39:37 2009
From: georgeoliverGO at gmail.com (George Oliver)
Date: Wed, 15 Jul 2009 13:39:37 -0700 (PDT)
Subject: interactive fiction in Python?
Message-ID: <5c97224b-99d4-469b-90cb-1c04b1e1e9a0@m11g2000yqh.googlegroups.com>

hi, I'm just curious who might be working on interactive fiction
modules in the style of Inform or TADS for Python. I've seen a few
threads on this list [1] (among many that mention IF tangentially),
and there are old projects like PUB and PAWS. There are some newer
potential projects such as Curveship as well. In any case I'd like to
see what's out there.


thanks, George


[1]:

http://bit.ly/Python_Text_Adventure_Authoring_System

http://bit.ly/simple_interactive_fiction_engine

http://bit.ly/adventure_engines_in_Python


From perfreem at gmail.com  Wed Jul 15 16:54:02 2009
From: perfreem at gmail.com (per)
Date: Wed, 15 Jul 2009 13:54:02 -0700 (PDT)
Subject: allowing output of code that is unittested?
Message-ID: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>

hi all,

i am using the standard unittest module to unit test my code. my code
contains several print statements which i noticed are repressed when i
call my unit tests using:

if __name__ == '__main__':
    suite = unittest.TestLoader().loadTestsFromTestCase(TestMyCode)
    unittest.TextTestRunner(verbosity=2).run(suite)

is there a way to allow all the print statements in the code that is
being run by the unit test functions to be printed to stdio?  i want
to be able to see the output of the tested code, in addition to the
output of the unit testing framework.

thank you.


From jkn_gg at nicorp.f9.co.uk  Wed Jul 15 17:25:24 2009
From: jkn_gg at nicorp.f9.co.uk (jkn)
Date: Wed, 15 Jul 2009 14:25:24 -0700 (PDT)
Subject: Ann: Google releases Python-based open-source NX server
Message-ID: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>

Google quietly releases open-source NX server ...written in Python,
apparently

<http://www.computerworld.com/s/article/9135504/
Google_quietly_releases_open_source_NX_server?taxonomyId=88>

Neatx can be downloaded from Google's code repository:

<http://code.google.com/p/neatx/>

    Regards
    J^n



From magobin at gmail.com  Wed Jul 15 17:26:53 2009
From: magobin at gmail.com (Alex)
Date: Wed, 15 Jul 2009 14:26:53 -0700 (PDT)
Subject: How to Force exiting from program/script
Message-ID: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>

hi at all,
 I have made a script with a while loop and I want that after 30
seconds the program stop and exit . But the code like this doesn't
run:
In the Console I can see work so that function is correctly called...

#Function to exit
def exit():
    print "work"
    raise SystemExit()
t = threading.Timer(30.0, exit)
t.start()

# Loop
while True:
...many lines....



From deets at nospam.web.de  Wed Jul 15 17:39:01 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 23:39:01 +0200
Subject: How to Force exiting from program/script
In-Reply-To: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>
References: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>
Message-ID: <7c70jlF25pt2sU1@mid.uni-berlin.de>

Alex schrieb:
> hi at all,
>  I have made a script with a while loop and I want that after 30
> seconds the program stop and exit . But the code like this doesn't
> run:
> In the Console I can see work so that function is correctly called...
> 
> #Function to exit
> def exit():
>     print "work"
>     raise SystemExit()
> t = threading.Timer(30.0, exit)
> t.start()
> 
> # Loop
> while True:
> ...many lines....
> 

This works for me:

import threading
import time

def work():
     while True:
         pass



t = threading.Thread(target=work)
t.setDaemon(True)
t.start()

time.sleep(10)
raise SystemExit


The trick is to raise the SystemExit in the main-thread.

Diez


From deets at nospam.web.de  Wed Jul 15 17:46:52 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 15 Jul 2009 23:46:52 +0200
Subject: allowing output of code that is unittested?
In-Reply-To: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>
References: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>
Message-ID: <7c712cF26q447U1@mid.uni-berlin.de>

per schrieb:
> hi all,
> 
> i am using the standard unittest module to unit test my code. my code
> contains several print statements which i noticed are repressed when i
> call my unit tests using:
> 
> if __name__ == '__main__':
>     suite = unittest.TestLoader().loadTestsFromTestCase(TestMyCode)
>     unittest.TextTestRunner(verbosity=2).run(suite)
> 
> is there a way to allow all the print statements in the code that is
> being run by the unit test functions to be printed to stdio?  i want
> to be able to see the output of the tested code, in addition to the
> output of the unit testing framework.


I use nosetests to discover & run tests, and that has an "-s"-option 
that does exactly that.

Diez


From mobiledreamers at gmail.com  Wed Jul 15 18:01:15 2009
From: mobiledreamers at gmail.com (mobiledreamers at gmail.com)
Date: Wed, 15 Jul 2009 15:01:15 -0700
Subject: Ann: Google releases Python-based open-source NX server
In-Reply-To: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
Message-ID: <c1870d60907151501i651a0ea8m11e03cd02624bcce@mail.gmail.com>

On Wed, Jul 15, 2009 at 2:25 PM, jkn <jkn_gg at nicorp.f9.co.uk> wrote:

> Google quietly releases open-source NX server ...written in Python,
> apparently
>
> <http://www.computerworld.com/s/article/9135504/
> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>
> Neatx can be downloaded from Google's code repository:
>
> <http://code.google.com/p/neatx/>
>
>    Regards
>    J^n
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Bidegg worlds best auction site
http://bidegg.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090715/a9bbf062/attachment-0001.html>

From nobody at nowhere.com  Wed Jul 15 18:31:38 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 15 Jul 2009 23:31:38 +0100
Subject: Colour of output text
References: <03c4ceed-c49b-4dd0-a585-e6169b02e0eb@26g2000yqk.googlegroups.com>
	<c8q5m.8137$Rb6.7235@flpi147.ffdc.sbc.com> <h371ba$36l$1@aioe.org>
	<pan.2009.07.11.06.24.02.406000@nowhere.com>
	<mailman.3163.1247670223.8015.python-list@python.org>
Message-ID: <pan.2009.07.15.22.31.38.0@nowhere.com>

On Wed, 15 Jul 2009 17:03:30 +0200, Jean-Michel Pichavant wrote:

>> Hard-coding control/escape sequences is just lame. Use the curses modules
>> to obtain the correct sequences for the terminal.
>>
>>   
> As the OP I'm really interested in doing so. I currently have all my 
> colors hard-coded.
> Now It may be lame but as soon as I call curses.initscr(), it's just 
> messing up with my terminal,

Use curses.setupterm() to locate and parse the terminfo/termcap entry
without entering "curses mode". Most curses functions won't work without
calling initscr(), but the terminfo functions will.

> moreover I didn't figure out how to "print  
> 'hello'" using curses color codes.
> Anyone has an example ? I'm pretty sure it may fit in one line.

#!/usr/bin/env python
import curses
curses.setupterm()
setaf = curses.tigetstr('setaf')
if not setaf:
    setaf = ''
print (curses.tparm(setaf,1) + "hello, " +
	curses.tparm(setaf,2) + "world" +
	curses.tparm(setaf,0))




From mmanns at gmx.net  Wed Jul 15 18:36:51 2009
From: mmanns at gmx.net (mmanns at gmx.net)
Date: Thu, 16 Jul 2009 00:36:51 +0200
Subject: Package for fast plotting of many data points in Python?
References: <0734dc45-d8a0-4f28-b945-f9e179f30f5c@h11g2000yqb.googlegroups.com>
	<e038b7f1-400f-43c7-85bc-df81170353c0@r34g2000vba.googlegroups.com>
Message-ID: <20090716003651.09bca73c@Knock>

On Sat, 11 Jul 2009 15:33:32 -0700 (PDT)
Daniel Platz <mail.to.daniel.platz at googlemail.com> wrote:

> thanks for your repleys. I have tried matplotlib but it is extremely
> slow. I think it is more optimized for good looking plots instead of
> speed. I do not know the Python bindings of gnuplot and Veusz. To
> clarify the issue again, by 25000 data points I mean 25000 pixels,
> i.e. corresponding (x,y) pairs. Thus the mapping to one pixel on the
> screen is not unique.

Have you already tried out rpy?

Martin


From shai at platonix.com  Wed Jul 15 18:45:57 2009
From: shai at platonix.com (Shai)
Date: Wed, 15 Jul 2009 15:45:57 -0700 (PDT)
Subject: Cleaning up after failing to contructing objects
References: <5d8aaf63-0072-49a0-8a60-0cd5aff02128@b15g2000yqd.googlegroups.com>
	<uOp5m.3783$ze1.731@news-server.bigpond.net.au>
	<42fbcee1-61b2-4ba8-a50a-39c9c0d2fe9c@k19g2000yqn.googlegroups.com>
Message-ID: <cbf0a92e-9e6d-4cd8-9c98-0ae9585cc282@y7g2000yqa.googlegroups.com>

Since nobody else mentioned this...

Python classes have a magic method called __del__ which is usually
called just before an object is garbage-collected. Further, Python
uses reference-counting to tell when an object is no longer
accessible. This means that if your resource classes define __del__
methods, these will be called properly when the object using them is
destroyed, and you don't need to write an explicit close() method for
this.

class Resource(object):
  def __init__(self, param):
    # acquire resource

  def __del__(self):
    # release resource

not_my_responsibility = Resource(1)

class Foo(object):
  def __init__(self):
     self.ref = not_my_responsibility # self.ref.__del__() will not be
called as long as the module exists
     local = Resource(2) # local.__del__() will be called as soon as
__init__ is exited
     self.held = Resource(3) # self.held.__del__() will be called when
the object dies
     z = 1/0 # The exception in the initializer will kill the object,
triggering some Resource.__del__() calls

There are two caveats:

1) __del__ methods prevent instances of your class from being
collected when they are involved in cyclical structures; this means if
your structures start to get complex (sometimes a doubly-linked list
is complex enough), you may find yourself leaking memory.

2) The bit about reference counting, which allows predictable
destruction, holds for CPython, but not for Jython, and IIRC also not
for IronPython (I don't know about PyPy or other implementations). It
is a feature of the reference implementation, not the language
definition.


From wbrehaut at mcsnet.ca  Wed Jul 15 18:54:00 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 16:54:00 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
Message-ID: <7bns55dch1pler31ai2ivdp1u6nk60lnfo@4ax.com>

On Tue, 14 Jul 2009 11:47:41 -0700 (PDT), Mark Dickinson
<dickinsm at gmail.com> wrote:

>On Jul 14, 7:25?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
>wrote:
>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice to
>> have an 'xor' operator as well.
>
>Hmm.  I don't think 'nice' is sufficient.  You'd need to make the case
>that it's sufficiently useful to justify adding a new keyword 'xor' to
>the language;  I suspect that would be an uphill struggle. :)

=== 8< ===
And for the objects for which it *is* sufficiently useful (sets) the
xor operator ^ is available:

>>> cheese = set(['cheddar', 'limburger', 'stilton'])
>>> stinky = set(['skunk', 'limburger', 'stilton', 'polecat', 'doggy-doo', 'civet'])
>>> nasty = set(['doggy-doo', 'polecat', 'limburger', 'Perl'])
>>> cheese & stinky # stinky cheese
set(['limburger', 'stilton'])
>>> cheese ^ stinky # either cheese or stinky but not both
set(['doggy-doo', 'civet', 'polecat', 'skunk', 'cheddar'])
>>> cheese ^ stinky ^ nasty # in an odd number of these sets (1 or 3)
set(['civet', 'cheddar', 'Perl', 'limburger', 'skunk'])

wayne


From wbrehaut at mcsnet.ca  Wed Jul 15 18:57:59 2009
From: wbrehaut at mcsnet.ca (Wayne Brehaut)
Date: Wed, 15 Jul 2009 16:57:59 -0600
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
Message-ID: <ipbs551ll266hf3p0v7anfqo86erisldrs@4ax.com>

On 15 Jul 2009 09:11:44 GMT, Steven D'Aprano
<steven at REMOVE.THIS.cybersource.com.au> wrote:

>On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
>
>> Current Boolean operators are 'and', 'or', and 'not'.  It would be nice
>> to have an 'xor' operator as well.
>
>I've often wished there was too, for the sake of completeness and 
>aesthetics, I'd love to be able to write:
>
>a xor b
>
>instead of defining a function xor(a, b).
>
>Unfortunately, outside of boolean algebra and simulating electrical 
>circuits, I can't think of any use-cases for an xor operator. Do you have 
>any?

Since xor in set theory is the symmetric difference,  perhaps we'd
like to know all items in exactly one of two word lists or
dictionaries, or anything else we could easily set-ize:

>>> cheese = set(['cheddar', 'limburger', 'stilton'])
>>> stinky = set(['skunk', 'limburger', 'stilton', 'polecat', 'doggy-doo', 'civet'])
>>> nasty = set(['doggy-doo', 'polecat', 'limburger', 'Perl'])
>>> cheese & stinky # stinky cheese
set(['limburger', 'stilton'])
>>> cheese ^ stinky # either cheese or stinky but not both
set(['doggy-doo', 'civet', 'polecat', 'skunk', 'cheddar'])
>>> cheese ^ stinky ^ nasty # in an odd number of these sets (1 or 3)
set(['civet', 'cheddar', 'Perl', 'limburger', 'skunk'])

Who hasn't needed that occasionally?

wayne


From nobody at nowhere.com  Wed Jul 15 19:01:37 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 00:01:37 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
Message-ID: <pan.2009.07.15.23.01.37.844000@nowhere.com>

On Wed, 15 Jul 2009 21:05:16 +0200, Jean-Michel Pichavant wrote:

> So if I resume:
> - not 'foo' => False
> - 'foo' or 'foo' => 'foo'
> 
> I may be missing something, but honestly, Guido must have smoked some 
> heavy stuff to write such logic, has he ?

Several languages (e.g. Lisp, Bourne shell) behave the same way, i.e. "or"
returns the first element which is considered true while "and" returns the
last element provided that all preceding elements are considered true.

> Let's play again
> False or 'foo' => 'foo'
> False and 'foo' => False
> 
> So funny. I would have expected boolean operators to return a boolean 
> value.

In Python, almost everything is a boolean value.

Compare with Lisp, where everything is a boolean value: nil (the empty
list) is false and everything else (including integer zero) is true.



From clp2 at rebertia.com  Wed Jul 15 19:02:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 16:02:13 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <ipbs551ll266hf3p0v7anfqo86erisldrs@4ax.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<ipbs551ll266hf3p0v7anfqo86erisldrs@4ax.com>
Message-ID: <50697b2c0907151602j393935eas4d5e18394baaa639@mail.gmail.com>

On Wed, Jul 15, 2009 at 3:57 PM, Wayne Brehaut<wbrehaut at mcsnet.ca> wrote:
> On 15 Jul 2009 09:11:44 GMT, Steven D'Aprano
> <steven at REMOVE.THIS.cybersource.com.au> wrote:
>
>>On Tue, 14 Jul 2009 11:25:08 -0700, Dr. Phillip M. Feldman wrote:
>>
>>> Current Boolean operators are 'and', 'or', and 'not'. ?It would be nice
>>> to have an 'xor' operator as well.
>>
>>I've often wished there was too, for the sake of completeness and
>>aesthetics, I'd love to be able to write:
>>
>>a xor b
>>
>>instead of defining a function xor(a, b).
>>
>>Unfortunately, outside of boolean algebra and simulating electrical
>>circuits, I can't think of any use-cases for an xor operator. Do you have
>>any?
>
> Since xor in set theory is the symmetric difference, ?perhaps we'd
> like to know all items in exactly one of two word lists or
> dictionaries, or anything else we could easily set-ize:
>
>>>> cheese = set(['cheddar', 'limburger', 'stilton'])
>>>> stinky = set(['skunk', 'limburger', 'stilton', 'polecat', 'doggy-doo', 'civet'])
>>>> nasty = set(['doggy-doo', 'polecat', 'limburger', 'Perl'])
>>>> cheese & stinky # stinky cheese
> set(['limburger', 'stilton'])
>>>> cheese ^ stinky # either cheese or stinky but not both
> set(['doggy-doo', 'civet', 'polecat', 'skunk', 'cheddar'])
>>>> cheese ^ stinky ^ nasty # in an odd number of these sets (1 or 3)
> set(['civet', 'cheddar', 'Perl', 'limburger', 'skunk'])
>
> Who hasn't needed that occasionally?

This discussion is about adding a *logical* operator for use in
boolean expressions. We obviously already have ^ for non-boolean use.

Cheers,
Chris
-- 
http://blog.rebertia.com


From pdlemper at earthlink.net  Wed Jul 15 20:07:18 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Wed, 15 Jul 2009 19:07:18 -0500
Subject: Can module tell if running from interpreter vs Windows command line ?
Message-ID: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>

The WConio console module produces different colors, sometimes quite
different, when run from Windows command line vs from Python
interpreter >>> .  A good foregnd/backgnd combination under one
may be unreadable under the other  : (
I'm using Python 3.0 with the corresponding WConio on XP.
Is there any way for the module to detect under which it has been 
started ?    Thanks


From pavlovevidence at gmail.com  Wed Jul 15 20:18:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 15 Jul 2009 17:18:52 -0700 (PDT)
Subject: import module unbelieveable behaviour
References: <mailman.3157.1247667587.8015.python-list@python.org>
Message-ID: <c134cd82-495a-4084-8929-f08ba435a2a7@i6g2000yqj.googlegroups.com>

On Jul 15, 6:12?am, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> Dear conference!
>
> I have test Why python based script for HeeksCNC post-processing does not
> work... ?And I've got unbelievable behavior ?When importing module module
> manually it works, but same opertaion from script does not
> ?work as seen
>
> /opt/HeeksCAD8/HeeksCNC> python
> Python 2.6 (r26:66714, Feb ?3 2009, 20:49:49)
> [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> Type "help", "copyright", "credits" or "license" for more information.>>> import nc.rez
>
> /opt/HeeksCAD8/HeeksCNC> python test.py
> Traceback (most recent call last):
> ? File "test.py", line 7, in <module>
> ? ? import nc.rez
> ImportError: No module named rez
>
> /opt/HeeksCAD8/HeeksCNC> python ./test.py
> Traceback (most recent call last):
> ? File "./test.py", line 7, in <module>
> ? ? import nc.rez
> ImportError: No module named rez
>
> Would anyone be helpful for me to get more information about this problem
> because ?pydb does not show anything usable for me,please?


That's a tricky one, indeed.

Here's my guess: test.py is a symlink to a file in another directory.

A major difference between interactive and script mode is the value of
sys.path[0], which is the directory Python uses for local modules and
packages.  Python uses the current directory when running in
interactive mode, but it uses the directory where the script is
located when it is called on a script.

Normally, when you run python on a script in the current directory,
the behavior is the same as interactive mode, because the directory
where the script is located is the current directory.  But there's the
gotcha: when you run python on symlinked file, Python sets sys.path[0]
to the directory containing the actual file, not the directory
containing the symlink.  Thus even if the symlink is in the current
directory, sys.path[0] is set to a different one.

As a workaround, test.py should explicitly add '' to sys.path:

sys.path.insert(0,'')


There is another notable difference in behavior between the two
modes.  In interactive mode, sys.path[0] is ''.  If you were to change
the current directory from within Python, using os.chdir(), then
future imports will occur relative to the new current directory.
However, if you run Python from a script, sys.path[0] is an actual
directory name, so that even if you chdir, any future imports will
still occur relative to the original directory.

Pretty confusing if you ask me.  Unfortunately Python is very
unPythonic when it comes to importing.  :(


Carl Banks


From http  Wed Jul 15 20:32:34 2009
From: http (Paul Rubin)
Date: 15 Jul 2009 17:32:34 -0700
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<ae7da03e-5852-4dbe-b11c-37f4afc32dbe@n11g2000yqb.googlegroups.com>
Message-ID: <7x3a8xwjq5.fsf@ruckus.brouhaha.com>

Anthony Tolle <anthony.tolle at gmail.com> writes:
> def xor(*operands):
>     if operands:
>         operands = list(operands)
>         a = bool(operands.pop(0))
>         while operands:
>             b = bool(operands.pop(0))
>             if a:
>                 if b:
>                     a = False
>             elif b:
>                 a = True
>         return a
>     return False

Among other things, that uses quadratic time!  Why do you want to keep
popping items from that list instead of iterating through it anyway?

Anyway, I think you wrote something close to this:

def xor(*operands):
   r = False
   for x in operands:
      r = (r != bool(x))
   return r

or in map-reduce style:

    from operator import ne
    def xor(*operands):
       return reduce(ne, map(bool, operands), False)


From wuwei23 at gmail.com  Wed Jul 15 20:41:41 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 17:41:41 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
Message-ID: <02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>

On Jul 16, 10:07?am, pdlem... at earthlink.net wrote:
> The WConio console module produces different colors, sometimes quite
> different, when run from Windows command line vs from Python
> interpreter >>> . ?A good foregnd/backgnd combination under one
> may be unreadable under the other ?: (
> I'm using Python 3.0 with the corresponding WConio on XP.
> Is there any way for the module to detect under which it has been
> started ? ? ?Thanks

It's recommended that you search through the list for similar
questions before posting. This was covered just yesterday:
http://groups.google.com/group/comp.lang.python/browse_frm/thread/fb2f075ccc796b63#


From wuwei23 at gmail.com  Wed Jul 15 20:47:39 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 17:47:39 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
Message-ID: <52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com>

On Jul 16, 10:41?am, alex23 <wuwe... at gmail.com> wrote:
> It's recommended that you search through the list for similar
> questions before posting.

Of course, it's even MORE important that one actually ensures they're
responding to the _same_ question before pointing at an answer...

This older post should help:
http://groups.google.com/group/comp.lang.python/browse_frm/thread/6c587ba377ae045a/0df10b077f5ee5d4

But the quick answer is to import sys into your program, and do a test
on hasattr(sys, 'ps1'), which is only created when running the
interactive prompt.


From pdlemper at earthlink.net  Wed Jul 15 21:36:57 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Wed, 15 Jul 2009 20:36:57 -0500
Subject: Can module tell if running from interpreter vs Windows command
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
Message-ID: <oq0t55pmvlsgt1p0ves5jm7mtl2a74rq0g@4ax.com>

On Wed, 15 Jul 2009 19:07:18 -0500, pdlemper at earthlink.net wrote:

>The WConio console module produces different colors, sometimes quite
>different, when run from Windows command line vs from Python
>interpreter >>> .  A good foregnd/backgnd combination under one
>may be unreadable under the other  : (
>I'm using Python 3.0 with the corresponding WConio on XP.
>Is there any way for the module to detect under which it has been 
>started ?    Thanks
Thanks Alex   It worked :

   import sys
   
   hasattr(sys, 'ps1')   yields True when started from interpreter >>>
                            and False run from Windows command line
Dave WB3DWE


From wuwei23 at gmail.com  Wed Jul 15 22:30:11 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 19:30:11 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com> 
	<56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com>
Message-ID: <30a6179e-f08a-4809-8c3d-50e083114d50@y10g2000prg.googlegroups.com>

On Jul 15, 5:51?pm, koranthala <koranth... at gmail.com> wrote:
> ? ?I am not saying that what you said was wrong, only that I felt that
> she got tense looking up regular expressions. So a python reply which
> basically does the basic checking without going to re etc might be
> more helpful for her to start her own coding.

Using regexps wasn't the only advice given, and string manipulation is
covered well in pretty much every tutorial I've taken a look at. The
issue is that no evidence was shown that the OP was even trying to
resolve this themself, and the new posting of the question every time
an unsatisfactory answer was provided doesn't give me any faith they
were endeavouring to do this at all.

It's annoying seeing these "stone soup" attempts at coding come
through here, whether its to answer someone's homework or to do
someone's job for them. If the end result has value to the poster, I
expect to see either effort on their behalf or at least a nominal
attempt to reward others for their time.

But if you want to do their work for them, I don't think anyone here
would object, especially if you both took it to private correspondence.


From afriere at yahoo.co.uk  Wed Jul 15 22:56:38 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Wed, 15 Jul 2009 19:56:38 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
	<52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com>
Message-ID: <0fc81395-7787-48a9-93de-cf7a274b691e@u38g2000pro.googlegroups.com>

On Jul 16, 10:47?am, alex23 <wuwe... at gmail.com> wrote:

...

> This older post should help:http://groups.google.com/group/comp.lang.python/browse_frm/thread/6c5...
>
> But the quick answer is to import sys into your program, and do a test
> on hasattr(sys, 'ps1'), which is only created when running the
> interactive prompt.

As you note there, this will work when running the vanilla shell (ie
running  it from the command line), but not (potentially) in other
interactive environments (IronPython being the example you give).
Another instance:  there is not sys.ps1 when running a python shell
under idle.  Since this solution differs whether the interactive
session is taking place from the cmd line, idle, IronPython etc. it
seems to me not terribly robust.

Depending on the use case, it is of course easy to tell whether the
module was executed on the command line, or imported (from an
interactive shell or another script) using the __name__ trick.  (eg.
is_imported = __name__ == '__main__')




From koranthala at gmail.com  Wed Jul 15 23:42:51 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 20:42:51 -0700 (PDT)
Subject: mail
References: <mailman.3184.1247683595.8015.python-list@python.org>
Message-ID: <55d3cd26-44a2-4b87-8bb4-988e8c397833@v15g2000prn.googlegroups.com>

On Jul 15, 11:46?pm, amr... at iisermohali.ac.in wrote:
> Dear all,
>
> Sorry that I am disturbing you all again and again but this is the way I
> am trying to solve my problem:---
>
> >>> import re
> >>> exp = re.compile("CA")
> >>> infile = open("file1.txt")
> >>> for line in infile:
>
> ... ? ? values = re.split("\s+", line)
> ... ? ? if exp.search(line):
> ... ? ? ? ?print ("%s %s CA = %s" %(values[2], values[3], values[6]))
> ...
> ?with this it is giving the output like:----
>
> 8 ALA CA = 54.67
> 15 ALA CA = 52.18
> 21 ALA CA = 54.33
> 23 ALA CA = 55.84
> 33 ALA CA = 55.58
> 38 ALA CA = 54.33
>
> which is all right but i want CB and C value also in each row and it
> should take value from 5th column infront of them, file is something
> lookin like:-----
>
> ?47 ? ? 8 ? ALA ? ? ? H ? ? H ? ? ?7.85 ? ? 0.02 ? ? 1
> ?48 ? ? 8 ? ALA ? ? ? HA ? ?H ? ? ?2.98 ? ? 0.02 ? ? 1
> ?49 ? ? 8 ? ALA ? ? ? HB ? ?H ? ? ?1.05 ? ? 0.02 ? ? 1
> ?50 ? ? 8 ? ALA ? ? ? C ? ? C ? ?179.39 ? ? ?0.3 ? ? 1
> ?51 ? ? 8 ? ALA ? ? ? CA ? ?C ? ? 54.67 ? ? ?0.3 ? ? 1
> ?52 ? ? 8 ? ALA ? ? ? CB ? ?C ? ? 18.85 ? ? ?0.3 ? ? 1
> ?53 ? ? 8 ? ALA ? ? ? N ? ? N ? ?123.95 ? ? ?0.3 ? ? 1
> 107 ? ?15 ? ALA ? ? ? H ? ? H ? ? ?8.05 ? ? 0.02 ? ? 1
> 108 ? ?15 ? ALA ? ? ? HA ? ?H ? ? ?4.52 ? ? 0.02 ? ? 1
> 109 ? ?15 ? ALA ? ? ? HB ? ?H ? ? ?1.29 ? ? 0.02 ? ? 1
> 110 ? ?15 ? ALA ? ? ? C ? ? C ? ?177.18 ? ? ?0.3 ? ? 1
> 111 ? ?15 ? ALA ? ? ? CA ? ?C ? ? 52.18 ? ? ?0.3 ? ? 1
> 112 ? ?15 ? ALA ? ? ? CB ? ?C ? ? 20.64 ? ? ?0.3 ? ? 1
> 113 ? ?15 ? ALA ? ? ? N ? ? N ? ?119.31 ? ? ?0.3 ? ? 1
> 154 ? ?21 ? ALA ? ? ? H ? ? H ? ? ?7.66 ? ? 0.02 ? ? 1
> 155 ? ?21 ? ALA ? ? ? HA ? ?H ? ? ?4.05 ? ? 0.02 ? ? 1
> 156 ? ?21 ? ALA ? ? ? HB ? ?H ? ? ?1.39 ? ? 0.02 ? ? 1
> 157 ? ?21 ? ALA ? ? ? C ? ? C ? ?179.35 ? ? ?0.3 ? ? 1
> 158 ? ?21 ? ALA ? ? ? CA ? ?C ? ? 54.33 ? ? ?0.3 ? ? 1
> 159 ? ?21 ? ALA ? ? ? CB ? ?C ? ? 17.87 ? ? ?0.3 ? ? 1
> 160 ? ?21 ? ALA ? ? ? N ? ? N ? ?123.58 ? ? ?0.3 ? ? 1
> 169 ? ?23 ? ALA ? ? ? H ? ? H ? ? ?8.78 ? ? 0.02 ? ? 1
> 170 ? ?23 ? ALA ? ? ? HA ? ?H ? ? ?4.14 ? ? 0.02 ? ? 1
> 171 ? ?23 ? ALA ? ? ? HB ? ?H ? ? ?1.62 ? ? 0.02 ? ? 1
> 172 ? ?23 ? ALA ? ? ? C ? ? C ? ?179.93 ? ? ?0.3 ? ? 1
> 173 ? ?23 ? ALA ? ? ? CA ? ?C ? ? 55.84 ? ? ?0.3 ? ? 1
> 174 ? ?23 ? ALA ? ? ? CB ? ?C ? ? 17.55 ? ? ?0.3 ? ? 1
> 175 ? ?23 ? ALA ? ? ? N ? ? N ? ?120.16 ? ? ?0.3 ? ? 1
> 232 ? ?33 ? ALA ? ? ? H ? ? H ? ? ?7.57 ? ? 0.02 ? ? 1
> 233 ? ?33 ? ALA ? ? ? HA ? ?H ? ? ?3.89 ? ? 0.02 ? ? 1
> 234 ? ?33 ? ALA ? ? ? HB ? ?H ? ? ?1.78 ? ? 0.02 ? ? 1
> 235 ? ?33 ? ALA ? ? ? C ? ? C ? ?179.24 ? ? ?0.3 ? ? 1
> 236 ? ?33 ? ALA ? ? ? CA ? ?C ? ? 55.58 ? ? ?0.3 ? ? 1
> 237 ? ?33 ? ALA ? ? ? CB ? ?C ? ? 19.75 ? ? ?0.3 ? ? 1
> 238 ? ?33 ? ALA ? ? ? N ? ? N ? ?121.52 ? ? ?0.3 ? ? 1
> 269 ? ?38 ? ALA ? ? ? H ? ? H ? ? ?8.29 ? ? 0.02 ? ? 1
> 270 ? ?38 ? ALA ? ? ? HA ? ?H ? ? ?4.04 ? ? 0.02 ? ? 1
> 271 ? ?38 ? ALA ? ? ? HB ? ?H ? ? ?1.35 ? ? 0.02 ? ? 1
> 272 ? ?38 ? ALA ? ? ? C ? ? C ? ?178.95 ? ? ?0.3 ? ? 1
> 273 ? ?38 ? ALA ? ? ? CA ? ?C ? ? 54.33 ? ? ?0.3 ? ? 1
> 274 ? ?38 ? ALA ? ? ? CB ? ?C ? ? 18.30 ? ? ?0.3 ? ? 1
> 275 ? ?38 ? ALA ? ? ? N ? ? N ? ?120.62 ? ? ?0.3 ? ? 1
>
> I just want that it will give output something like:-----
>
> 8 ?ALA ?C = 179.39 ?CA = 54.67 ?CB = 18.85
> 15 ALA ?C = 177.18 ?CA = 52.18 ?CB = 20.64
> 21 ALA ?C = 179.35 ?CA = 54.33 ?CB = 17.87.....
>
> so first it will write the position of the amino acid(given by second
> column)then amino acid here it is ALA and then the corresponding value of
> C, CA and CB from 5th colum for each position of ALA.
>
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA

Hi,
   Can you try using the code which I suggested in the earlier thread?
   If you cannot use it to get the output, just point it out here, and
I will try to solve the issue.


From nagle at animats.com  Thu Jul 16 00:03:58 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 15 Jul 2009 21:03:58 -0700
Subject: does python have a generic object pool like commons-pool in Java
In-Reply-To: <12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
Message-ID: <4a5ea61b$0$1682$742ec2ed@news.sonic.net>

Rick Lawson wrote:
> On Jul 15, 4:53 am, Jonathan Gardner <jgard... at jonathangardner.net>
> wrote:
>> On Jul 14, 6:34 pm, Rick Lawson <lawso... at gmail.com> wrote:
>>
>>> Appreciate any help on this. I am porting an app from Java to python
>>> and need generic object pooling with hooks for object initialization /
>>> cleanup and be able to specify an object timeout.
>> Are you looking for something like a thread pool or a connection pool?
>> Such a thing is easy to code in Python. Might as well write one from
>> scratch for your particular need.
>>
>> By the way, a tip for writing Python: Forget Java. If you're porting
>> an app, consider rewriting it from the architecture on up. You'll save
>> yourself time and get a better result.
> 
> Jonathan,
> 
> Thanks for the advice but would like to pick your brain a little more.
> The pool I need is not a thread pool or db pool. I need to pool
> objects which are a proxy for an external C process that communicates
> via sockets. 

     "fcgi" is an option for this sort of thing.  With "mod_fcgi" installed
in Apache, and "fcgi.py" used to manage the Python side of the problem, you
can have semi-persistent programs started up and shut down for you on the
server side.

    I use this for "sitetruth.com".  It's useful when CGI is too slow
because the cost of launching Python and loading all the modules is
far greater than the cost of processing the request.

    Once you find and install a working Apache "mod_fcgi" module, and a
working "fcgi.py" module (I suggest "http://svn.saddi.com/py-lib/trunk/fcgi.py") 
writing the server side app is no harder than with CGI.  But the performance
is far better.

				John Nagle


From wuwei23 at gmail.com  Thu Jul 16 00:14:37 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 21:14:37 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
	<52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com> 
	<0fc81395-7787-48a9-93de-cf7a274b691e@u38g2000pro.googlegroups.com>
Message-ID: <35b0b936-6bc1-4acf-aa27-6cc0db84292b@y10g2000prf.googlegroups.com>

On Jul 16, 12:56?pm, Asun Friere <afri... at yahoo.co.uk> wrote:
> As you note there, this will work when running the vanilla shell (ie
> running ?it from the command line), but not (potentially) in other
> interactive environments (IronPython being the example you give).

Actually, that was IPython, which is an enhanced interactive prompt,
and a totally different beastie altogether :)

> Another instance: ?there is not sys.ps1 when running a python shell
> under idle. ?Since this solution differs whether the interactive
> session is taking place from the cmd line, idle, IronPython etc. it
> seems to me not terribly robust.

Well, none of {idle, IronPython, IPython} were specified by the OP AND
you're citing back what I myself wrote in the link to which I also
referred the OP - whom has subsequently posted his success with this
technique - so I'm not really sure what the point is here other than
"if you have a different use case, you'll need a different
solution"...

> Depending on the use case, it is of course easy to tell whether the
> module was executed on the command line, or imported (from an
> interactive shell or another script) using the __name__ trick.  (eg.
> is_imported = __name__ == '__main__')

That should be:

is_imported = __name__ != '__main__'

And such a test is all well and good if the main code body is the one
that needs to know about the execution mode, but if you need to know
under which conditions the program is being run within a module
imported by the main body, well, that check is _always_ going to be
true...


From phostu at gmail.com  Thu Jul 16 00:18:39 2009
From: phostu at gmail.com (Vincent)
Date: Wed, 15 Jul 2009 21:18:39 -0700 (PDT)
Subject: problem about cx_Oracle
Message-ID: <957ab843-92ac-4072-ace4-441a2da0d130@m3g2000pri.googlegroups.com>

hi, all:

i am using cx_oracle now.

i write code as below:

def __getfields_by_tbname(self,tbname):
        cursor = self.ora_db.cursor()
        print tbname
        sql = 'select * from %s where rownum <=2' % tbname
        print sql
        cursor = cursor.execute(sql)
        return self.getfields(cursor)

and i got a error, it's message is :
JRYZCFZB_X_ZQY
select * from JRYZCFZB_X_ZQY where rownum <=2
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
\data_convert.py", line 107, in convert
    self.convert_table(tbname)
  File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
\data_convert.py", line 94, in convert_table
    field_list = self.__getfields_by_tbname(tbname)
  File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
\data_convert.py", line 38, in __getfields_by_tbname
    cursor = cursor.execute(sql)
TypeError: expecting None or a string

i'm sure the cursor instance is not None.
could anybody give me sussgestion? i will apreciate it.

vincent


From koranthala at gmail.com  Thu Jul 16 00:29:04 2009
From: koranthala at gmail.com (koranthala)
Date: Wed, 15 Jul 2009 21:29:04 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com> 
	<56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com> 
	<30a6179e-f08a-4809-8c3d-50e083114d50@y10g2000prg.googlegroups.com>
Message-ID: <ee806cef-f159-4aae-b768-2c62eb3457b8@m3g2000pri.googlegroups.com>

On Jul 16, 7:30?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 15, 5:51?pm, koranthala <koranth... at gmail.com> wrote:
>
> > ? ?I am not saying that what you said was wrong, only that I felt that
> > she got tense looking up regular expressions. So a python reply which
> > basically does the basic checking without going to re etc might be
> > more helpful for her to start her own coding.
>
> Using regexps wasn't the only advice given, and string manipulation is
> covered well in pretty much every tutorial I've taken a look at. The
> issue is that no evidence was shown that the OP was even trying to
> resolve this themself, and the new posting of the question every time
> an unsatisfactory answer was provided doesn't give me any faith they
> were endeavouring to do this at all.
>
> It's annoying seeing these "stone soup" attempts at coding come
> through here, whether its to answer someone's homework or to do
> someone's job for them. If the end result has value to the poster, I
> expect to see either effort on their behalf or at least a nominal
> attempt to reward others for their time.
>
> But if you want to do their work for them, I don't think anyone here
> would object, especially if you both took it to private correspondence.

It is not that I do want to do the work for them. It is just that I
was in the same position just 6 months back. My first pieces of code
were very poor - full of errors and quite horrible indeed. I was even
afraid to post it anywhere. I came here, and I found so much helpful
people who helped me out so much, that I think my coding has improved
a little bit. So, I just thought that we should always give people the
benefit of doubt.



From wuwei23 at gmail.com  Thu Jul 16 00:30:40 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 21:30:40 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com> 
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com> 
	<4a5ea61b$0$1682$742ec2ed@news.sonic.net>
Message-ID: <0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>

On Jul 16, 2:03?pm, John Nagle <na... at animats.com> wrote:
> ? ? ?"fcgi" is an option for this sort of thing. ?With "mod_fcgi" installed
> in Apache, and "fcgi.py" used to manage the Python side of the problem, you
> can have semi-persistent programs started up and shut down for you on the
> server side.

Hey John,

The environments in which I've been asked to develop webs apps using
Python have all utilised mod_wsgi. Do you have any experience with
mod_wsgi vs mod_fcgi, and if so, can you comment on any relevant
performance / capability / ease-of-use differences?

Cheers,
alex23




From akhilanger at gmail.com  Thu Jul 16 00:34:06 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 21:34:06 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
	position 13: ordinal not in range(128)
Message-ID: <24509879.post@talk.nabble.com>


Hi!

Can anyone please help me getting rid of this error:
UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
13: ordinal not in range(128)

I am not a python programmer (though intend to start learning this wonderful
language), I am just using a python script.

After doing some search, I found that 0xb7 is a 'middle dot character' that
is not interpreted by the python.
Even after inserting text = text.replace('\u00b7', '') in the script, the
problem still persists.

Can anyone please tell me the easiest way to get rid of this?

--Thanks,
Akhil
-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24509879.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From clp2 at rebertia.com  Thu Jul 16 00:39:19 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 21:39:19 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
In-Reply-To: <24509879.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
Message-ID: <50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>

On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>
> Hi!
>
> Can anyone please help me getting rid of this error:
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
> 13: ordinal not in range(128)
>
> I am not a python programmer (though intend to start learning this wonderful
> language), I am just using a python script.
>
> After doing some search, I found that 0xb7 is a 'middle dot character' that
> is not interpreted by the python.
> Even after inserting text = text.replace('\u00b7', '') in the script, the
> problem still persists.
>
> Can anyone please tell me the easiest way to get rid of this?

We'll need the full error traceback. The error message at the end is
just not enough information.
As to fixing it, google for "UnicodeEncodeError". You should find
about a million mailinglist threads on it.

Cheers,
Chris
-- 
http://blog.rebertia.com


From wuwei23 at gmail.com  Thu Jul 16 00:41:31 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 15 Jul 2009 21:41:31 -0700 (PDT)
Subject: one more question
References: <mailman.3134.1247638396.8015.python-list@python.org> 
	<045a6d36-8b65-44bf-909a-8831e6bf1bbf@t13g2000yqt.googlegroups.com> 
	<c83dfef0-faed-4880-803c-66dba5286d59@h11g2000yqb.googlegroups.com> 
	<56406040-baec-4dae-9b04-5f1472028bdc@k1g2000yqf.googlegroups.com> 
	<30a6179e-f08a-4809-8c3d-50e083114d50@y10g2000prg.googlegroups.com> 
	<ee806cef-f159-4aae-b768-2c62eb3457b8@m3g2000pri.googlegroups.com>
Message-ID: <0f28ec7c-f0cc-4cfb-a518-e65dba6e094c@12g2000pri.googlegroups.com>

On Jul 16, 2:29?pm, koranthala <koranth... at gmail.com> wrote:
> It is not that I do want to do the work for them. It is just that I
> was in the same position just 6 months back. My first pieces of code
> were very poor - full of errors and quite horrible indeed. I was even
> afraid to post it anywhere. I came here, and I found so much helpful
> people who helped me out so much, that I think my coding has improved
> a little bit. So, I just thought that we should always give people the
> benefit of doubt.

Which is why I waited until the 5th repeated post on the topic before
commenting.


From nagle at animats.com  Thu Jul 16 01:05:01 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 15 Jul 2009 22:05:01 -0700
Subject: does python have a generic object pool like commons-pool in Java
In-Reply-To: <0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com>
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com>
	<4a5ea61b$0$1682$742ec2ed@news.sonic.net>
	<0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>
Message-ID: <4a5eb46a$0$1673$742ec2ed@news.sonic.net>

alex23 wrote:
> On Jul 16, 2:03 pm, John Nagle <na... at animats.com> wrote:
>>      "fcgi" is an option for this sort of thing.  With "mod_fcgi" installed
>> in Apache, and "fcgi.py" used to manage the Python side of the problem, you
>> can have semi-persistent programs started up and shut down for you on the
>> server side.
> 
> Hey John,
> 
> The environments in which I've been asked to develop webs apps using
> Python have all utilised mod_wsgi. Do you have any experience with
> mod_wsgi vs mod_fcgi, and if so, can you comment on any relevant
> performance / capability / ease-of-use differences?
> 
> Cheers,
> alex23

    FCGI seems to be somewhat out of favor, perhaps because it isn't
complicated enough. It's a mature technology and works reasonably
well.  It's been a puzzle to me that FCGI was taken out of the
main Apache code base, because it gives production-level performance
with CGI-type simplicity.

    WSGI has a mode for running Python inside the Apache process,
which is less secure and doesn't allow multiple Python processes.
That complicates mod_wsgi considerably, and ties it very closely
to specific versions of Python and Python modules.  As a result,
the WSGI developers are patching at a great rate.  I think the
thing has too many "l33t features".

I'd avoid "embedded mode".  "Daemon mode" is the way to go if you use WSGI.
I haven't tried WSGI; I don't need the grief of a package under
heavy development.

					John Nagle


From akhilanger at gmail.com  Thu Jul 16 01:05:20 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 22:05:20 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
Message-ID: <24510222.post@talk.nabble.com>


Well, 
All I get is this traceback:

File "./customWikiExtractor.py", line 492, in ?
     main()
File "./customWikiExtractor.py", line 480, in main
    print >> sys.stdout, 'line: %s' % line
UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
13: ordinal not in range(128)

I am giving a string to the python code as input, and python processes it
like this:

line = line.decode('utf-8').strip()

After this when I do, 
print >> sys.stdout, 'line: %s' % line
I get this Unicode error.

I tried a few repairs, but they did not work like
changing: in sgmmlib.py (/usr/lib64/python2.4/sgmmlib.py) 
if not 0 < n <= 255
    to
if not 0 < n <= 127 

But since this did not work, I have changed it back to it's original form.

--Thanks,
Akhil


Chris Rebert-6 wrote:
> 
> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>
>> Hi!
>>
>> Can anyone please help me getting rid of this error:
>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>> position
>> 13: ordinal not in range(128)
>>
>> I am not a python programmer (though intend to start learning this
>> wonderful
>> language), I am just using a python script.
>>
>> After doing some search, I found that 0xb7 is a 'middle dot character'
>> that
>> is not interpreted by the python.
>> Even after inserting text = text.replace('\u00b7', '') in the script, the
>> problem still persists.
>>
>> Can anyone please tell me the easiest way to get rid of this?
> 
> We'll need the full error traceback. The error message at the end is
> just not enough information.
> As to fixing it, google for "UnicodeEncodeError". You should find
> about a million mailinglist threads on it.
> 
> Cheers,
> Chris
> -- 
> http://blog.rebertia.com
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24510222.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From akhilanger at gmail.com  Thu Jul 16 01:09:38 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 22:09:38 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <24510222.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
Message-ID: <24510252.post@talk.nabble.com>


Sorry, it is sgmllib.py and not sgmmlib.py

-- Akhil

akhil1988 wrote:
> 
> Well, 
> All I get is this traceback:
> 
> File "./customWikiExtractor.py", line 492, in ?
>      main()
> File "./customWikiExtractor.py", line 480, in main
>     print >> sys.stdout, 'line: %s' % line
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
> position 13: ordinal not in range(128)
> 
> I am giving a string to the python code as input, and python processes it
> like this:
> 
> line = line.decode('utf-8').strip()
> 
> After this when I do, 
> print >> sys.stdout, 'line: %s' % line
> I get this Unicode error.
> 
> I tried a few repairs, but they did not work like
> changing: in sgmmlib.py (/usr/lib64/python2.4/sgmmlib.py) 
> if not 0 < n <= 255
>     to
> if not 0 < n <= 127 
> 
> But since this did not work, I have changed it back to it's original form.
> 
> --Thanks,
> Akhil
> 
> 
> Chris Rebert-6 wrote:
>> 
>> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>>
>>> Hi!
>>>
>>> Can anyone please help me getting rid of this error:
>>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>>> position
>>> 13: ordinal not in range(128)
>>>
>>> I am not a python programmer (though intend to start learning this
>>> wonderful
>>> language), I am just using a python script.
>>>
>>> After doing some search, I found that 0xb7 is a 'middle dot character'
>>> that
>>> is not interpreted by the python.
>>> Even after inserting text = text.replace('\u00b7', '') in the script,
>>> the
>>> problem still persists.
>>>
>>> Can anyone please tell me the easiest way to get rid of this?
>> 
>> We'll need the full error traceback. The error message at the end is
>> just not enough information.
>> As to fixing it, google for "UnicodeEncodeError". You should find
>> about a million mailinglist threads on it.
>> 
>> Cheers,
>> Chris
>> -- 
>> http://blog.rebertia.com
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24510252.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From clp2 at rebertia.com  Thu Jul 16 01:12:08 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 15 Jul 2009 22:12:08 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
In-Reply-To: <24510222.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
Message-ID: <50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>

> Chris Rebert-6 wrote:
>>
>> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>>
>>> Hi!
>>>
>>> Can anyone please help me getting rid of this error:
>>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>>> position
>>> 13: ordinal not in range(128)
>>>
>>> I am not a python programmer (though intend to start learning this
>>> wonderful
>>> language), I am just using a python script.
>>>
>>> After doing some search, I found that 0xb7 is a 'middle dot character'
>>> that
>>> is not interpreted by the python.
>>> Even after inserting text = text.replace('\u00b7', '') in the script, the
>>> problem still persists.
>>>
>>> Can anyone please tell me the easiest way to get rid of this?
>>
>> We'll need the full error traceback. The error message at the end is
>> just not enough information.
>> As to fixing it, google for "UnicodeEncodeError". You should find
>> about a million mailinglist threads on it.
On Wed, Jul 15, 2009 at 10:05 PM, akhil1988<akhilanger at gmail.com> wrote:
>
> Well,
> All I get is this traceback:
>
> File "./customWikiExtractor.py", line 492, in ?
>     main()
> File "./customWikiExtractor.py", line 480, in main
>    print >> sys.stdout, 'line: %s' % line
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in position
> 13: ordinal not in range(128)
>
> I am giving a string to the python code as input, and python processes it
> like this:
>
> line = line.decode('utf-8').strip()
>
> After this when I do,
> print >> sys.stdout, 'line: %s' % line
> I get this Unicode error.

Try this instead (the ">> sys.stdout" part is redundant):
print (u'line: %s' % line).encode('utf8')
#if your system doesn't use UTF-8, change as necessary

Cheers,
Chris
-- 
http://blog.rebertia.com


From peter.fodrek at stuba.sk  Thu Jul 16 01:16:57 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 07:16:57 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <7c6bdkF26j00sU1@mid.uni-berlin.de>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<7c6bdkF26j00sU1@mid.uni-berlin.de>
Message-ID: <200907160716.57648.peter.fodrek@stuba.sk>


On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:
> Peter Fodrek wrote:
......
> What does
>
> import nc
> print nc.__file__

python
Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
[GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import nc
>>> print nc.__file__
nc/__init__.pyc

and as well

ls nc             
attach.py       hpgl2dv_read.py  iso_codes.pyc  nc_read.py     
emc2.py         hpgl3d.py        iso.py         nc_read.pyc    rez.pyc
emc2_read.py    hpgl3d_read.py   iso_read.py    num_reader.py  rez_read.py
hpgl2d.py       __init__.py      machines.txt   rez_codes.py   siegkx1.py 
hpgl2d_read.py  __init__.pyc     nc.py               siegkx1_read.py
hpgl2dv.py      iso_codes.py     nc.pyc         rez.py     


and module is compiled well
ls -la nc/rez*
-rwxr-xr-x 1 peto users  1391 2009-07-15 13:18 nc/rez_codes.py
-rwxrwxrwx 1 peto users   255 2009-07-15 14:28 nc/rez.py
-rwxr-xr-x 1 peto users   222 2009-07-15 14:28 nc/rez.pyc
-rwxr-xr-x 1 peto users  5920 2009-07-15 13:17 nc/rez_read.py

Thank you 

Peter


From peter.fodrek at stuba.sk  Thu Jul 16 01:20:53 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 07:20:53 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <c134cd82-495a-4084-8929-f08ba435a2a7@i6g2000yqj.googlegroups.com>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<c134cd82-495a-4084-8929-f08ba435a2a7@i6g2000yqj.googlegroups.com>
Message-ID: <200907160720.53656.peter.fodrek@stuba.sk>

On Thursday 16 July 2009 02:18:52 Carl Banks wrote:
> On Jul 15, 6:12 am, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> That's a tricky one, indeed.
>
> Here's my guess: test.py is a symlink to a file in another directory.

It is not true guess
ls -la test.py
-rw-r--r-- 1 peto users 1990 2009-07-15 14:19 test.py  

But maybe access rights  needed to be corrected...

Thank you 

Peter


From mensanator at aol.com  Thu Jul 16 01:28:31 2009
From: mensanator at aol.com (Mensanator)
Date: Wed, 15 Jul 2009 22:28:31 -0700 (PDT)
Subject: Why does Python not stop when it's supposed to?
Message-ID: <539781e9-1096-499e-851a-8d3e8247e52d@f10g2000vbf.googlegroups.com>

So, I'm playing around with Python (running 2.6 and
3.1 versions of IDLE). After I shut everything down
and close the windows, I notice the Task Manager's
activity light is still glowing.

In looking at the Process window I see this:

Image...    User Name  CPU Memory(... Description
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      216 K pythonw.exe
pythonw.exe mensanator  00      220 K pythonw.exe
pythonw.exe mensanator  00      220 K pythonw.exe
pythonw.exe mensanator  00      408 K pythonw.exe
pythonw.exe mensanator  00      180 K pythonw.exe
pythonw.exe mensanator  50   66,156 K pythonw.exe
pythonw.exe mensanator  00      600 K pythonw.exe
pythonw.exe mensanator  00      228 K pythonw.exe
pythonw.exe mensanator  00      208 K pythonw.exe
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      192 K pythonw.exe
pythonw.exe mensanator  00      224 K pythonw.exe
pythonw.exe mensanator  00      180 K pythonw.exe
pythonw.exe mensanator  00    8,672 K pythonw.exe

I can't seem to reproduce this. Opening IDLE
causes two copies to appear. When RUN, a third
appears for a few moments and drops back to two.

Doing a RESTART SHELL also launches another copy
which also goes away momentarily.

So, with a 2.6 and a 3.1 IDLE running simultaneously,
there could be 6 copies at once.

And they eventually all go away when the windows
are closed.

How is it I end up with 16 copies, one of them still
running after all the windows are closed? I had to
manually do an [end process] on all of them.

If I was doing something wrong, i sure would like
to know what it is.


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 16 01:37:02 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 16 Jul 2009 05:37:02 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.05.37.03@REMOVE.THIS.cybersource.com.au>

On Wed, 15 Jul 2009 21:05:16 +0200, Jean-Michel Pichavant wrote:

> Didn't know that.
> So if I resume:
> - not 'foo' => False
> - 'foo' or 'foo' => 'foo'
> 
> I may be missing something, but honestly, Guido must have smoked some
> heavy stuff to write such logic, has he ?

No, it's perfectly reasonable, and not at all the product of mind-
altering drugs. Other languages do the same thing.


for x in alist or blist or clist:
    print x

will select the first non-empty list and iterate over that.



Every object in Python has a truth value. By convention, we say that 
objects are Something or Nothing.

0 None [] '' are examples of Nothing, or false values.

1 2.5 [x, y, z] 'foo' are examples of Something, or true values.

Note the distinction between lower-case "false" and "true" (adjectives), 
and title-case False and True (nouns).


`if x: ... else:` branches according to whether x is Something or 
Nothing, not whether it is True or False.

The operators `and` and `or` also return Something or Nothing, short-
circuiting as appropriate.



-- 
Steven


From phostu at gmail.com  Thu Jul 16 01:38:10 2009
From: phostu at gmail.com (Vincent)
Date: Wed, 15 Jul 2009 22:38:10 -0700 (PDT)
Subject: problem about cx_Oracle
References: <957ab843-92ac-4072-ace4-441a2da0d130@m3g2000pri.googlegroups.com>
Message-ID: <717d5451-ef6d-45df-9e77-2135c75f7a12@u38g2000pro.googlegroups.com>

On Jul 16, 12:18?pm, Vincent <pho... at gmail.com> wrote:
> hi, all:
>
> i am using cx_oracle now.
>
> i write code as below:
>
> def __getfields_by_tbname(self,tbname):
> ? ? ? ? cursor = self.ora_db.cursor()
> ? ? ? ? print tbname
> ? ? ? ? sql = 'select * from %s where rownum <=2' % tbname
> ? ? ? ? print sql
> ? ? ? ? cursor = cursor.execute(sql)
> ? ? ? ? return self.getfields(cursor)
>
> and i got a error, it's message is :
> JRYZCFZB_X_ZQY
> select * from JRYZCFZB_X_ZQY where rownum <=2
> Traceback (most recent call last):
> ? File "<input>", line 1, in <module>
> ? File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
> \data_convert.py", line 107, in convert
> ? ? self.convert_table(tbname)
> ? File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
> \data_convert.py", line 94, in convert_table
> ? ? field_list = self.__getfields_by_tbname(tbname)
> ? File "c:/vincent/wd/django/mysite/mysite\..\mysite\tools
> \data_convert.py", line 38, in __getfields_by_tbname
> ? ? cursor = cursor.execute(sql)
> TypeError: expecting None or a string
>
> i'm sure the cursor instance is not None.
> could anybody give me sussgestion? i will apreciate it.
>
> vincent

i have the answer now.

the variant sql is unicode.

i neet to convert it to string.



From pavlovevidence at gmail.com  Thu Jul 16 01:38:23 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 15 Jul 2009 22:38:23 -0700 (PDT)
Subject: import module unbelieveable behaviour
References: <mailman.3157.1247667587.8015.python-list@python.org> 
	<7c6bdkF26j00sU1@mid.uni-berlin.de>
	<mailman.3196.1247721417.8015.python-list@python.org>
Message-ID: <2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>

On Jul 15, 10:16?pm, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:
>
> > Peter Fodrek wrote:
> ......
> > What does
>
> > import nc
> > print nc.__file__
>
> python
> Python 2.6 (r26:66714, Feb ?3 2009, 20:49:49)
> [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> Type "help", "copyright", "credits" or "license" for more information.>>> import nc
> >>> print nc.__file__
>
> nc/__init__.pyc


What does it do if you run this from a script?

Also, what is sys.path[0] in both interactive and script?

Inside test.py, right before the line that imports nc.rez, add the
code "import sys; print sys.modules.get('nc')"; what does that output?

Is there an old nc.py or nc.pyc file anywhere?


Carl Banks

Carl Banks


From afriere at yahoo.co.uk  Thu Jul 16 01:44:40 2009
From: afriere at yahoo.co.uk (Asun Friere)
Date: Wed, 15 Jul 2009 22:44:40 -0700 (PDT)
Subject: Can module tell if running from interpreter vs Windows command 
	line ?
References: <n4rs555es0n97sjubkhduiuoq6u34fhhvf@4ax.com>
	<02dbb097-c0b2-46b9-9ea7-f1212518b283@12g2000pri.googlegroups.com>
	<52883754-fd57-450e-a6f0-00b55e510b08@y10g2000prg.googlegroups.com> 
	<0fc81395-7787-48a9-93de-cf7a274b691e@u38g2000pro.googlegroups.com> 
	<35b0b936-6bc1-4acf-aa27-6cc0db84292b@y10g2000prf.googlegroups.com>
Message-ID: <6c572443-cf8e-403c-aa66-086007dca540@d15g2000prc.googlegroups.com>

On Jul 16, 2:14?pm, alex23 <wuwe... at gmail.com> wrote:

...

> AND
> you're citing back what I myself wrote in the link to which I also
> referred the OP - whom (sic) has subsequently posted his success with this
> technique - so I'm not really sure what the point is here other than
> "if you have a different use case, you'll need a different
> solution"...
>

Please don't take offence where none was intended.  I know that I was
citing you and that I was highlighting the caveat you raised,
explicitly so.  No criticism of your post was intended nor implied.
Moreover the fact that it worked for OP on a single occasion does not
speak for its robustness.

> > Depending on the use case, it is of course easy to tell whether the
> > module was executed on the command line, or imported (from an
> > interactive shell or another script) using the __name__ trick. ?(eg.
> > is_imported = __name__ == '__main__')
>
> That should be:
>
> is_imported = __name__ != '__main__'
>

Doh! ... Yup I actually used that when I tried it out, my bad.

> And such a test is all well and good if the main code body is the one
> that needs to know about the execution mode, but if you need to know
> under which conditions the program is being run within a module
> imported by the main body, well, that check is _always_ going to be
> true...

Which is what the paragraph you just quoted says.  Hence the attribute
is called 'is_imported' rather that 'running_non_interactively'.


From akhilanger at gmail.com  Thu Jul 16 01:52:24 2009
From: akhilanger at gmail.com (akhil1988)
Date: Wed, 15 Jul 2009 22:52:24 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>
Message-ID: <24510519.post@talk.nabble.com>


Chris,

Using 

print (u'line: %s' % line).encode('utf-8')

the 'line' gets printed, but actually this print statement I was using just
for testing, actually my code operates on 'line', on which I use line =
line.decode('utf-8') as 'line' is read as bytes from a stream.

And if I use line = line.encode('utf-8'), 

I start getting other error like
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 4561:
ordinal not in range(128)
at line = line.replace('<<', u'?').replace('>>', u'?')


--Akhil

Chris Rebert-6 wrote:
> 
>> Chris Rebert-6 wrote:
>>>
>>> On Wed, Jul 15, 2009 at 9:34 PM, akhil1988<akhilanger at gmail.com> wrote:
>>>>
>>>> Hi!
>>>>
>>>> Can anyone please help me getting rid of this error:
>>>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>>>> position
>>>> 13: ordinal not in range(128)
>>>>
>>>> I am not a python programmer (though intend to start learning this
>>>> wonderful
>>>> language), I am just using a python script.
>>>>
>>>> After doing some search, I found that 0xb7 is a 'middle dot character'
>>>> that
>>>> is not interpreted by the python.
>>>> Even after inserting text = text.replace('\u00b7', '') in the script,
>>>> the
>>>> problem still persists.
>>>>
>>>> Can anyone please tell me the easiest way to get rid of this?
>>>
>>> We'll need the full error traceback. The error message at the end is
>>> just not enough information.
>>> As to fixing it, google for "UnicodeEncodeError". You should find
>>> about a million mailinglist threads on it.
> On Wed, Jul 15, 2009 at 10:05 PM, akhil1988<akhilanger at gmail.com> wrote:
>>
>> Well,
>> All I get is this traceback:
>>
>> File "./customWikiExtractor.py", line 492, in ?
>>     main()
>> File "./customWikiExtractor.py", line 480, in main
>>    print >> sys.stdout, 'line: %s' % line
>> UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' in
>> position
>> 13: ordinal not in range(128)
>>
>> I am giving a string to the python code as input, and python processes it
>> like this:
>>
>> line = line.decode('utf-8').strip()
>>
>> After this when I do,
>> print >> sys.stdout, 'line: %s' % line
>> I get this Unicode error.
> 
> Try this instead (the ">> sys.stdout" part is redundant):
> print (u'line: %s' % line).encode('utf8')
> #if your system doesn't use UTF-8, change as necessary
> 
> Cheers,
> Chris
> -- 
> http://blog.rebertia.com
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24510519.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From milesck at umich.edu  Thu Jul 16 01:59:54 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Thu, 16 Jul 2009 01:59:54 -0400
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <m2hbxdelqu.fsf@valheru.db3l.homeip.net>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<4a5cc8c0$0$1655$742ec2ed@news.sonic.net>
	<m2prc3dlfo.fsf@valheru.db3l.homeip.net>
	<mailman.3183.1247682273.8015.python-list@python.org>
	<m2hbxdelqu.fsf@valheru.db3l.homeip.net>
Message-ID: <1EAE7F84-0FA1-4688-8F2B-B5E6869E69B8@umich.edu>

On Jul 15, 2009, at 4:26 PM, David Bolen wrote:

> Miles Kaufmann <milesck at umich.edu> writes:
>
>> On Jul 14, 2009, at 5:06 PM, David Bolen wrote:
>>> Are you sure?  It seems to restrict them in the same block, but  
>>> not in
>>> the entire file.  At least I was able to use both space and tab
>>> indented blocks in the same file with Python 3.0 and 3.1.
>>
>> It seems to me that, within an indented block, Python 3.1 requires
>> that you are consistent in your use of indentation characters *for
>> that indentation level*.  For example, the following code seems to be
>> allowed:
>
> Um, right - in other words, what I said :-)

I wasn't trying to correct you, just being more explicit. :)  After  
reading your post, I still wasn't sure if the restriction on mixing  
spaces and tabs applied to nested blocks--I was surprised that the  
code sample I included was allowed.

-Miles



From list at qtrac.plus.com  Thu Jul 16 02:21:48 2009
From: list at qtrac.plus.com (Mark Summerfield)
Date: Wed, 15 Jul 2009 23:21:48 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
Message-ID: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>

Hi,

I'm just wondering why <, <=, >=, and > are not supported by
collections.OrderedDict:

    >>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
    >>> d2 = d1.copy()
    >>> d2["z"] = 4
    >>> d1 == d2
    False
    >>> d1 < d2
    Traceback (most recent call last):
    File "<pyshell#6>", line 1, in <module>
	d1 < d2
    TypeError: unorderable types: OrderedDict() < OrderedDict()

It just seems to me that since the items in ordered dictionaries are
ordered, it would make sense to do an item by item comparison from
first to last item in exactly the same way that Python compares lists
or tuples?


From peter.fodrek at stuba.sk  Thu Jul 16 02:38:57 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 08:38:57 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<mailman.3196.1247721417.8015.python-list@python.org>
	<2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>
Message-ID: <200907160838.57658.peter.fodrek@stuba.sk>

On Thursday 16 July 2009 07:38:23 Carl Banks wrote:
> On Jul 15, 10:16 pm, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> > On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:
> > > Peter Fodrek wrote:
> >
> > ......
> >
> > > What does
> > >
> > > import nc
> > > print nc.__file__
> >
> > python
> > Python 2.6 (r26:66714, Feb  3 2009, 20:49:49)
> > [GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
> > Type "help", "copyright", "credits" or "license" for more information.>>>
> > import nc
> >
> > >>> print nc.__file__
> >
> > nc/__init__.pyc
>
> What does it do if you run this from a script?

Ouch, I am and python rookie, that was needed to try to edit undocumented 
script from German author

this answers everything

/home/opt/HeeksCAD8/HeeksCNC> python ./test.py
/usr/local/lib/heekscnc/nc/__init__.py 

and it is because begining of the script

# -*- coding: utf-8 -*-
import sys
sys.path.insert(0,'/usr/local/lib/heekscnc/')
import kurve
import kurve_funcs
from nc.nc import *
import nc
print nc.__file__
import nc.rez

and

ls -a /usr/local/lib/heekscnc/nc
.          emc2_read.py    hpgl2dv_read.py  iso_codes.py  nc_read.py
..         hpgl2d.py       hpgl3d.py        iso.py        num_reader.py
attach.py  hpgl2d_read.py  hpgl3d_read.py   iso_read.py   siegkx1.py
emc2.py    hpgl2dv.py      __init__.py      nc.py         siegkx1_read.py

Thank you for your help, once more.


Peter


From peter.fodrek at stuba.sk  Thu Jul 16 02:48:55 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Thu, 16 Jul 2009 08:48:55 +0200
Subject: import module unbelieveable behaviour
In-Reply-To: <200907160838.57658.peter.fodrek@stuba.sk>
References: <mailman.3157.1247667587.8015.python-list@python.org>
	<2c30659f-0e89-4d1e-bfa0-e96032a813d0@n11g2000yqb.googlegroups.com>
	<200907160838.57658.peter.fodrek@stuba.sk>
Message-ID: <200907160848.55069.peter.fodrek@stuba.sk>

On Thursday 16 July 2009 08:38:57 Peter Fodrek wrote:
> On Thursday 16 July 2009 07:38:23 Carl Banks wrote:
> > On Jul 15, 10:16 pm, Peter Fodrek <peter.fod... at stuba.sk> wrote:
> > > On Wednesday 15 July 2009 17:41:54 Diez B. Roggisch wrote:

> sys.path.insert(0,'/usr/local/lib/heekscnc/')

I was mentioned that this adds system path to multipath list(As $PATH)  and it 
replaces path instead. That was problem..

Peter


From jackdied at gmail.com  Thu Jul 16 03:12:20 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Thu, 16 Jul 2009 03:12:20 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
Message-ID: <b8e622740907160012p10911831ub1488195d694e663@mail.gmail.com>

On Thu, Jul 16, 2009 at 2:21 AM, Mark Summerfield<list at qtrac.plus.com> wrote:
> Hi,
>
> I'm just wondering why <, <=, >=, and > are not supported by
> collections.OrderedDict:
>
> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
> ? ?>>> d2 = d1.copy()
> ? ?>>> d2["z"] = 4
> ? ?>>> d1 == d2
> ? ?False
> ? ?>>> d1 < d2
> ? ?Traceback (most recent call last):
> ? ?File "<pyshell#6>", line 1, in <module>
> ? ? ? ?d1 < d2
> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> It just seems to me that since the items in ordered dictionaries are
> ordered, it would make sense to do an item by item comparison from
> first to last item in exactly the same way that Python compares lists
> or tuples?

>>> import this
In the face of ambiguity, refuse the temptation to guess.

It isn't an OrderedDict thing, it is a comparison thing.  Two regular
dicts also raise an error if you try to LT them.  What does it mean
for a dict to be greater than or less than its peer?  Nothing, so we
refuse to guess.

-Jack


From list at qtrac.plus.com  Thu Jul 16 03:22:20 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 00:22:20 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
Message-ID: <9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>

On 16 July, 08:12, Jack Diederich <jackd... at gmail.com> wrote:
> On Thu, Jul 16, 2009 at 2:21 AM, Mark Summerfield<l... at qtrac.plus.com> wrote:
> > Hi,
>
> > I'm just wondering why <, <=, >=, and > are not supported by
> > collections.OrderedDict:
>
> > ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
> > ? ?>>> d2 = d1.copy()
> > ? ?>>> d2["z"] = 4
> > ? ?>>> d1 == d2
> > ? ?False
> > ? ?>>> d1 < d2
> > ? ?Traceback (most recent call last):
> > ? ?File "<pyshell#6>", line 1, in <module>
> > ? ? ? ?d1 < d2
> > ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> > It just seems to me that since the items in ordered dictionaries are
> > ordered, it would make sense to do an item by item comparison from
> > first to last item in exactly the same way that Python compares lists
> > or tuples?
> >>> import this
>
> In the face of ambiguity, refuse the temptation to guess.
>
> It isn't an OrderedDict thing, it is a comparison thing. ?Two regular
> dicts also raise an error if you try to LT them. ?What does it mean
> for a dict to be greater than or less than its peer? ?Nothing, so we
> refuse to guess.
>
> -Jack

You are right that it doesn't make sense to compare two dicts.

But OrderedDicts can be viewed logically as lists of (key,value)
tuples so they are much more like lists or tuples when it comes to
comparisons.

For example:

>>> l = [("a", 1), ("z", 2), ("k", 3)]
>>> l1 = l[:]
>>> l1[1] = ("z", 5)
>>> l < l1
True

But if you do:

>>> d = collections.OrderedDict(l)
>>> d1 = collections.OrderedDict(l1)

You can't use <, <=, =>, or >, even though ordered dictionaries
preserve the order and their items are just as comparable as those in
a list or tuple of tuples.


From nagle at animats.com  Thu Jul 16 03:26:18 2009
From: nagle at animats.com (John Nagle)
Date: Thu, 16 Jul 2009 00:26:18 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
In-Reply-To: <mailman.3194.1247720980.8015.python-list@python.org>
References: <24509879.post@talk.nabble.com>	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>	<24510222.post@talk.nabble.com>
	<mailman.3194.1247720980.8015.python-list@python.org>
Message-ID: <4a5ed587$0$1627$742ec2ed@news.sonic.net>

akhil1988 wrote:
> Sorry, it is sgmllib.py and not sgmmlib.py

    Oh, that bug again.  See

	http://bugs.python.org/issue1651995

It's a bug in SGMLParser.  When Python 2.5 restricted ASCII to 0..127,
SGMLParser needed to be modified, but wasn't.

I reported that bug in February 2007.  It was fixed in
Python 2.6 and 3.0 on March 31, 2009.

					John Nagle


From clp2 at rebertia.com  Thu Jul 16 03:30:26 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 00:30:26 -0700
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
Message-ID: <50697b2c0907160030x5abbf7a4i99d397236297c850@mail.gmail.com>

On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<list at qtrac.plus.com> wrote:
> Hi,
>
> I'm just wondering why <, <=, >=, and > are not supported by
> collections.OrderedDict:
>
> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3)))
> ? ?>>> d2 = d1.copy()
> ? ?>>> d2["z"] = 4
> ? ?>>> d1 == d2
> ? ?False
> ? ?>>> d1 < d2
> ? ?Traceback (most recent call last):
> ? ?File "<pyshell#6>", line 1, in <module>
> ? ? ? ?d1 < d2
> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> It just seems to me that since the items in ordered dictionaries are
> ordered, it would make sense to do an item by item comparison from
> first to last item in exactly the same way that Python compares lists
> or tuples?

Use case? I'm curious.

Cheers,
Chris
-- 
http://blog.rebertia.com


From mail at microcorp.co.za  Thu Jul 16 03:43:53 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Thu, 16 Jul 2009 09:43:53 +0200
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org><057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com><50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com><h3j358$lhr$1@ger.gmane.org><mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <001201ca05e9$2b0a61e0$0d00a8c0@Hendrik>

"Hrvoje Niksic" <hniksic at x..s.org> wrote:


> Note that in Python A or B is in fact not equivalent to not(not A and
> not B).

De Morgan would turn in his grave.

- Hendrik




From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 16 03:51:29 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 16 Jul 2009 07:51:29 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au>

On Thu, 16 Jul 2009 00:30:26 -0700, Chris Rebert wrote:

> On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<list at qtrac.plus.com>
> wrote:
>> Hi,
>>
>> I'm just wondering why <, <=, >=, and > are not supported by
>> collections.OrderedDict:
>>
>> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3))) d2 =
>> ? ?>>> d1.copy()
>> ? ?>>> d2["z"] = 4
>> ? ?>>> d1 == d2
>> ? ?False
>> ? ?>>> d1 < d2
>> ? ?Traceback (most recent call last):
>> ? ?File "<pyshell#6>", line 1, in <module>
>> ? ? ? ?d1 < d2
>> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>>
>> It just seems to me that since the items in ordered dictionaries are
>> ordered, it would make sense to do an item by item comparison from
>> first to last item in exactly the same way that Python compares lists
>> or tuples?
> 
> Use case? I'm curious.


Surely it would be the same use case as for comparing two lists? There 
doesn't need to be a special "OrderedDict use case" beyond "an 
OrderedDict is just like a list of (key,value) tuples, but searches are 
faster".

Or maybe not. If OrderedDicts are sequences as well as mappings, then we 
should be able to sort them. And that seems a bit much even for me.



-- 
Steven


From eckhardt at satorlaser.com  Thu Jul 16 03:56:13 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Thu, 16 Jul 2009 09:56:13 +0200
Subject: allowing output of code that is unittested?
References: <d2f07709-7594-4379-ad7e-c50ecd57959c@a26g2000yqn.googlegroups.com>
Message-ID: <t133j6-g3a.ln1@satorlaser.homedns.org>

per wrote:
> i am using the standard unittest module to unit test my code. my code
> contains several print statements which i noticed are repressed when i
> call my unit tests using:
> 
> if __name__ == '__main__':
>     suite = unittest.TestLoader().loadTestsFromTestCase(TestMyCode)
>     unittest.TextTestRunner(verbosity=2).run(suite)

I have here

   if __name__ == '__main__':
       unittest.main()

preceded by classes which derive from unittest.TestCase. Running this allows
me to write to stdout using print as usual, even though it's ugly because
it clutters the output of the testcases.

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 16 04:19:21 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 16 Jul 2009 08:19:21 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<mailman.3205.1247730432.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.08.19.21@REMOVE.THIS.cybersource.com.au>

On Thu, 16 Jul 2009 09:43:53 +0200, Hendrik van Rooyen wrote:

> "Hrvoje Niksic" <hniksic at x..s.org> wrote:
> 
> 
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
> 
> De Morgan would turn in his grave.

No he wouldn't. Python isn't Boolean algebra, and there is no requirement 
to limit Python's operators to the semantics of Boolean algebra.



-- 
Steven


From info at egenix.com  Thu Jul 16 04:28:10 2009
From: info at egenix.com (eGenix Team: M.-A. Lemburg)
Date: Thu, 16 Jul 2009 10:28:10 +0200
Subject: EuroPython 2009: Making 50 Mio. EUR per year using Python
Message-ID: <4A5EE49A.8000207@egenix.com>

Now available as video...

http://www.egenix.com/company/news/EuroPython-2009-Lightning-Talk.html

Enjoy,
-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 16 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/




From vmalloc at gmail.com  Thu Jul 16 04:43:32 2009
From: vmalloc at gmail.com (Rotem)
Date: Thu, 16 Jul 2009 01:43:32 -0700 (PDT)
Subject: Memory leak involving traceback objects
Message-ID: <e6e9b9ea-1f8c-4695-90da-72e85c8a63e4@v20g2000yqm.googlegroups.com>

Hi,

I'm debugging a nasty memory leak in a framework written in Python
(v2.6.2).
After much digging around I found that the entire object group that is
leaking is held by a frame object which is subsequently held by a
traceback object.

Traversing the get_referrers() of each traceback frame leads
eventually to a root traceback frame which has no referrers
(gc.get_referrers returns an empty list).

However, this traceback object seems not to be picked by the garbage
collector, and is still there even after many iterations and calls to
gc.collect(). The code location to which the traceback frame points
doesn't do anything special - it just catches an exception, without
saving the exception itself and/or traceback anywhere.

Before I dive into the Python code itself - does anyone have any idea
what can cause this?

Thanks,

Rotem


From piet at cs.uu.nl  Thu Jul 16 04:48:57 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 10:48:57 +0200
Subject: How to Force exiting from program/script
References: <c4eb1258-1242-4e07-8bbc-496079f32146@b14g2000yqd.googlegroups.com>
Message-ID: <m28wipvwqu.fsf@cs.uu.nl>

>>>>> Alex <magobin at gmail.com> (A) a ?crit:

>A> hi at all,
>A>  I have made a script with a while loop and I want that after 30
>A> seconds the program stop and exit . But the code like this doesn't
>A> run:
>A> In the Console I can see work so that function is correctly called...

>A> #Function to exit
>A> def exit():
>A>     print "work"
>A>     raise SystemExit()
>A> t = threading.Timer(30.0, exit)
>A> t.start()

>A> # Loop
>A> while True:
>A> ...many lines....

This code gives you a bit more control as it doesn't just force a system
exit, but allows you to continue some other work after aborting the
loop:

import signal, os
from threading import Timer

signalcode = signal.SIGALRM
class AlarmError(Exception):
    pass

def handler(signum, frame):
    raise AlarmError, "command lasts too long"

signal.signal(signalcode, handler)

def interrupt():
    os.kill(os.getpid(), signalcode)

def execute(function, timeout):
    Timer(timeout, interrupt).start()
    try:
        function()
    except AlarmError, e:
        print e
        print 'Execution aborted'

def long_function():
    while True:
        pass
    
print "The everlasting command"
execute(long_function, 10)
print "The End"

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From l.mastrodomenico at gmail.com  Thu Jul 16 05:02:55 2009
From: l.mastrodomenico at gmail.com (Lino Mastrodomenico)
Date: Thu, 16 Jul 2009 11:02:55 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <001201ca05e9$2b0a61e0$0d00a8c0@Hendrik>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<001201ca05e9$2b0a61e0$0d00a8c0@Hendrik>
Message-ID: <cc93256f0907160202u3dc09e8av2b31ad755ca01b39@mail.gmail.com>

2009/7/16 Hendrik van Rooyen <mail at microcorp.co.za>:
> "Hrvoje Niksic" <hniksic at x..s.org> wrote:
>
>
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
>
> De Morgan would turn in his grave.

If this can make him happier, in Python (not (not a and not b)) *is*
equivalent to bool(a or b). (Modulo crazy things like redefining
"bool" or having a __bool__ with side effects.)

In the first expression you implicitly request a bool because you use
"not", in the second one you do this with an explicit "bool".

-- 
Lino Mastrodomenico


From jeanmichel at sequans.com  Thu Jul 16 05:06:54 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 16 Jul 2009 11:06:54 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.15.23.01.37.844000@nowhere.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
Message-ID: <4A5EEDAE.3040605@sequans.com>

Nobody wrote:
> On Wed, 15 Jul 2009 21:05:16 +0200, Jean-Michel Pichavant wrote:
>
>   
>> So if I resume:
>> - not 'foo' => False
>> - 'foo' or 'foo' => 'foo'
>>
>> I may be missing something, but honestly, Guido must have smoked some 
>> heavy stuff to write such logic, has he ?
>>     
>
> Several languages (e.g. Lisp, Bourne shell) behave the same way, i.e. "or"
> returns the first element which is considered true while "and" returns the
> last element provided that all preceding elements are considered true.
>   
> [snip]
>   

Ok then, why "or" does not return True, if the first element is 
considered True ? Why returning the element itself. Any reason for that 
? Because it's confusing, maybe people used to that logic find it 
obvious, but I really don't.

JM


From piet at cs.uu.nl  Thu Jul 16 05:09:51 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 11:09:51 +0200
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<50697b2c0907152212s5c198cdaqeb7cd97b5295163@mail.gmail.com>
	<mailman.3198.1247723546.8015.python-list@python.org>
Message-ID: <m24otdvvs0.fsf@cs.uu.nl>

>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:

>a> Chris,

>a> Using 

>a> print (u'line: %s' % line).encode('utf-8')

>a> the 'line' gets printed, but actually this print statement I was using just
>a> for testing, actually my code operates on 'line', on which I use line =
>a> line.decode('utf-8') as 'line' is read as bytes from a stream.

>a> And if I use line = line.encode('utf-8'), 

>a> I start getting other error like
>a> UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 4561:
>a> ordinal not in range(128)
>a> at line = line.replace('<<', u'?').replace('>>', u'?')

You do a Unicode replace here, so line should be a unicode string.
Therefore you have to do this before the line.encode('utf-8'), but after
the decode('utf-8'). 

It might be better to use different variables for Unicode strings and
byte code strings to prevent confusion, like:

'line' is read as bytes from a stream
uline = line.decode('utf-8')
uline = uline.replace('<<', u'?').replace('>>', u'?')
line = uline.encode('utf-8')
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jarausch at igpm.rwth-aachen.de  Thu Jul 16 05:12:25 2009
From: jarausch at igpm.rwth-aachen.de (Helmut Jarausch)
Date: Thu, 16 Jul 2009 11:12:25 +0200
Subject: How to search this newsgroup by a python script.
Message-ID: <7c897lF26dea4U1@mid.dfncis.de>

Hi,

I haven't found anything with Google's group search, so let me
ask it (again?).

How can I search this newsgroup from within a Python script.
(Perhaps by searching Google Groups or Gmane by some Python code.)

Many thanks for a hint,
Helmut.

-- 
Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany


From piet at cs.uu.nl  Thu Jul 16 05:21:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 11:21:54 +0200
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>
Message-ID: <m2zlb5ugnh.fsf@cs.uu.nl>

>>>>> Mark <list at qtrac.plus.com> (M) wrote:

>M> You are right that it doesn't make sense to compare two dicts.

>M> But OrderedDicts can be viewed logically as lists of (key,value)
>M> tuples so they are much more like lists or tuples when it comes to
>M> comparisons.

>M> For example:

>>>>> l = [("a", 1), ("z", 2), ("k", 3)]
>>>>> l1 = l[:]
>>>>> l1[1] = ("z", 5)
>>>>> l < l1
>M> True

>M> But if you do:

>>>>> d = collections.OrderedDict(l)
>>>>> d1 = collections.OrderedDict(l1)

>M> You can't use <, <=, =>, or >, even though ordered dictionaries
>M> preserve the order and their items are just as comparable as those in
>M> a list or tuple of tuples.

But why should the order be as if the OrderedDict was a list of tuples.
A dict can be considered as a mapping and then you might want to treat
either the key or the value as contravariant (the key I guess). So there
is ambiguity. Why would the view as a list of tuples for the ordering be
the `natural' view? 

Maybe you may expect some kind of monotonicity such that d1<d2 implies
d1[x]<d2[x], but that doesn't work for d1 = {1:10, 2:20} and d2 = {1:15,
2:5}. So maybe there is only a partial ordering?

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rob.hooft at gmail.com  Thu Jul 16 05:25:27 2009
From: rob.hooft at gmail.com (rwwh)
Date: Thu, 16 Jul 2009 02:25:27 -0700 (PDT)
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com> 
	<op.uwmrrek9x6zn5v@lepton.softlabbsas.com.ar>
	<4A519AC0.1050905@islandtraining.com> 
	<op.uwmyoqdmx6zn5v@lepton.softlabbsas.com.ar>
	<mailman.2674.1246866966.8015.python-list@python.org> 
	<h2sckg$eng$2@lust.ihug.co.nz>
	<mailman.2677.1246869173.8015.python-list@python.org> 
	<HvA4m.3141$ze1.109@news-server.bigpond.net.au>
	<006eb461$0$9711$c3e8da3@news.astraweb.com> 
	<mailman.2755.1246947020.8015.python-list@python.org>
	<006f13c9$0$9711$c3e8da3@news.astraweb.com>
Message-ID: <1712a4da-fb9f-416e-9190-4da55fcc40ea@b14g2000yqd.googlegroups.com>

On Jul 7, 2:00?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Mon, 06 Jul 2009 22:18:20 -0700, Chris Rebert wrote:
> >> Not so rare. Decimal uses unary plus. Don't assume +x is a no-op.
> [...]
> > Well, yes, but when would you apply it twice in a row?
>
> My point was that unary + isn't a no-op, and therefore neither is ++. For
> Decimal, I can't think why you'd want to apply ++x, but for other
> objects, who knows?
>
> Here's a toy example:
>
> >>> class Spam(str):
>
> ... ? ? def __pos__(self):
> ... ? ? ? ? return self.__class__("spam " + self)
> ...>>> s = Spam("")
> >>> ++++s
>
> 'spam spam spam spam '

Here's another toy example:

class Toy(int):
    def __init__(self, value):
        self._incrd = False
        int.__init__(self, value)

    def incrHalf(self):
        self._incrd = True

    def __pos__(self):
        if self._incrd:
            return self.__class__(self+1)
        else:
            p = self.__class__(self)
            p.incrHalf()
            return p

    def __add__(self, other):
        return self.__class__(int(self)+other)

nows122[126]~% python -i toy.py
>>> i=Toy(5)
>>> +i
5
>>> ++i
6
>>> +++i
6
>>> +i++i
10
>>> +(+i++i)
10
>>> (++i)++i
11


From clp2 at rebertia.com  Thu Jul 16 05:33:24 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 02:33:24 -0700
Subject: How to search this newsgroup by a python script.
In-Reply-To: <7c897lF26dea4U1@mid.dfncis.de>
References: <7c897lF26dea4U1@mid.dfncis.de>
Message-ID: <50697b2c0907160233j70ba360fv69f6f48e509b55aa@mail.gmail.com>

On Thu, Jul 16, 2009 at 2:12 AM, Helmut
Jarausch<jarausch at igpm.rwth-aachen.de> wrote:
> Hi,
>
> I haven't found anything with Google's group search, so let me
> ask it (again?).
>
> How can I search this newsgroup from within a Python script.
> (Perhaps by searching Google Groups or Gmane by some Python code.)

1. Generate URL of the form:
http://search.gmane.org/?query=foo&group=gmane.comp.python.general
where "foo" is the search terms, with proper URL escaping applied.
2. Fetch URL using urllib - http://docs.python.org/library/urllib.html
3. Parse resulting HTML page (e.g. using BeautifulSoup)
4. Extract desired information from search results using the parse tree.
5. ???
6. Profit!

Cheers,
Chris
-- 
http://blog.rebertia.com


From mail at timgolden.me.uk  Thu Jul 16 05:38:05 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Thu, 16 Jul 2009 10:38:05 +0100
Subject: How to search this newsgroup by a python script.
In-Reply-To: <50697b2c0907160233j70ba360fv69f6f48e509b55aa@mail.gmail.com>
References: <7c897lF26dea4U1@mid.dfncis.de>
	<50697b2c0907160233j70ba360fv69f6f48e509b55aa@mail.gmail.com>
Message-ID: <4A5EF4FD.7080708@timgolden.me.uk>

Chris Rebert wrote:
> On Thu, Jul 16, 2009 at 2:12 AM, Helmut
> Jarausch<jarausch at igpm.rwth-aachen.de> wrote:
>> Hi,
>>
>> I haven't found anything with Google's group search, so let me
>> ask it (again?).
>>
>> How can I search this newsgroup from within a Python script.
>> (Perhaps by searching Google Groups or Gmane by some Python code.)
> 
> 1. Generate URL of the form:
> http://search.gmane.org/?query=foo&group=gmane.comp.python.general
> where "foo" is the search terms, with proper URL escaping applied.
> 2. Fetch URL using urllib - http://docs.python.org/library/urllib.html
> 3. Parse resulting HTML page (e.g. using BeautifulSoup)
> 4. Extract desired information from search results using the parse tree.
> 5. ???
> 6. Profit!

Alternatively, you could do something with the mailing list archive:

  http://mail.python.org/pipermail/python-list/

The .gz files are gzipped mbox format so can be dropped into, eg,
Thunderbird for offline browsing, or searched with the email
package from the stdlib.

TJG


From user at example.net  Thu Jul 16 06:34:20 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 12:34:20 +0200
Subject: using timers to force an execution time
Message-ID: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>

hello.

based upon previuos suggestions, i tried to write a program in which i 
would like to have a certain code fragment to execute only for a 
specified amount of time (say 3 seconds), then bail out.

but i get the following:

$ cat tmr004.py
#!/usr/bin/python -u

import threading , time

e = threading.Event()
t = threading.Timer(3.0, e.set)
t.start()
print time.asctime(time.localtime(time.time()))
while not e.isSet():
     for repeat in range(10):
         print time.time()
         time.sleep(0.66)
print time.asctime(time.localtime(time.time()))
$ ./tmr004.py
Thu Jul 16 12:31:27 2009
1247740287.44
1247740288.1
1247740288.76
1247740289.42
1247740290.08
1247740290.74
1247740291.4
1247740292.06
1247740292.72
1247740293.38
Thu Jul 16 12:31:34 2009
$

see? the while body ran for about 7 seconds... i bet it has to do with 
the fact that the timer does not control inner loops... any suggestion?

$ python -V
Python 2.3.4
$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
$

bye


From contact at xavierho.com  Thu Jul 16 06:49:07 2009
From: contact at xavierho.com (Xavier Ho)
Date: Thu, 16 Jul 2009 18:49:07 +0800
Subject: using timers to force an execution time
In-Reply-To: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <2d56febf0907160349k7c4eaa50t42216ce85bcb1689@mail.gmail.com>

On Thu, Jul 16, 2009 at 6:34 PM, superpollo <user at example.net> wrote:

> hello.
>
> based upon previuos suggestions, i tried to write a program in which i
> would like to have a certain code fragment to execute only for a specified
> amount of time (say 3 seconds), then bail out.
>
> <snip>


> see? the while body ran for about 7 seconds... i bet it has to do with the
> fact that the timer does not control inner loops... any suggestion?
>
>
I'm guessing it has to do with a sleep of 0.66 seconds x 10 times = sleep
for 6.6 seconds, and then it checks for e.isSet().

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/5eb781e8/attachment-0001.html>

From list at qtrac.plus.com  Thu Jul 16 06:50:25 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 03:50:25 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>
	<m2zlb5ugnh.fsf@cs.uu.nl>
Message-ID: <d3da1b04-0ebb-47a0-88aa-8d214cbf774b@24g2000yqm.googlegroups.com>

On 16 July, 10:21, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Mark <l... at qtrac.plus.com> (M) wrote:
> >M> You are right that it doesn't make sense to compare two dicts.
> >M> But OrderedDicts can be viewed logically as lists of (key,value)
> >M> tuples so they are much more like lists or tuples when it comes to
> >M> comparisons.
> >M> For example:
> >>>>> l = [("a", 1), ("z", 2), ("k", 3)]
> >>>>> l1 = l[:]
> >>>>> l1[1] = ("z", 5)
> >>>>> l < l1
> >M> True
> >M> But if you do:
> >>>>> d = collections.OrderedDict(l)
> >>>>> d1 = collections.OrderedDict(l1)
> >M> You can't use <, <=, =>, or >, even though ordered dictionaries
> >M> preserve the order and their items are just as comparable as those in
> >M> a list or tuple of tuples.
>
> But why should the order be as if the OrderedDict was a list of tuples.
> A dict can be considered as a mapping and then you might want to treat
> either the key or the value as contravariant (the key I guess). So there
> is ambiguity. Why would the view as a list of tuples for the ordering be
> the `natural' view?
>
> Maybe you may expect some kind of monotonicity such that d1<d2 implies
> d1[x]<d2[x], but that doesn't work for d1 = {1:10, 2:20} and d2 = {1:15,
> 2:5}. So maybe there is only a partial ordering?

OK, that seems to me to be a convincing argument against supporting
ordering.


From user at example.net  Thu Jul 16 06:56:50 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 12:56:50 +0200
Subject: turtle dump
Message-ID: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>

hi there.

is there a way to dump the content of a turtle window to a file or a 
file object?

bye


From list at qtrac.plus.com  Thu Jul 16 06:58:08 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 03:58:08 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
	<pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au>
Message-ID: <401967fb-c12e-4f63-8b05-6dffa0688028@a26g2000yqn.googlegroups.com>

On 16 July, 08:51, Steven D'Aprano
<ste... at REMOVE.THIS.cybersource.com.au> wrote:
> On Thu, 16 Jul 2009 00:30:26 -0700, Chris Rebert wrote:
> > On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<l... at qtrac.plus.com>
> > wrote:
> >> Hi,
>
> >> I'm just wondering why <, <=, >=, and > are not supported by
> >> collections.OrderedDict:
>
> >> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3))) d2 =
> >> ? ?>>> d1.copy()
> >> ? ?>>> d2["z"] = 4
> >> ? ?>>> d1 == d2
> >> ? ?False
> >> ? ?>>> d1 < d2
> >> ? ?Traceback (most recent call last):
> >> ? ?File "<pyshell#6>", line 1, in <module>
> >> ? ? ? ?d1 < d2
> >> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> >> It just seems to me that since the items in ordered dictionaries are
> >> ordered, it would make sense to do an item by item comparison from
> >> first to last item in exactly the same way that Python compares lists
> >> or tuples?
>
> > Use case? I'm curious.
>
> Surely it would be the same use case as for comparing two lists? There
> doesn't need to be a special "OrderedDict use case" beyond "an
> OrderedDict is just like a list of (key,value) tuples, but searches are
> faster".
>
> Or maybe not. If OrderedDicts are sequences as well as mappings, then we
> should be able to sort them. And that seems a bit much even for me.
>
> --
> Steven

One thing that I've just noticed is that you can use <, <=, >=, and >
with sets:

>>> s1 = {1,2,3}
>>> s2 = {1,2,4}
>>> s1 == s2
False
>>> s1 < s2
False
>>> s1 <= s2
False
>>> s2 < s1
False
>>> s2 <= s1
False
>>> s1 != s2
True

It seems a bit inconsistent that with sets you always get False when
using an ordering operator but with an ordered dict you get an
exception?


From list at qtrac.plus.com  Thu Jul 16 06:59:47 2009
From: list at qtrac.plus.com (Mark)
Date: Thu, 16 Jul 2009 03:59:47 -0700 (PDT)
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
	<pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au> 
	<401967fb-c12e-4f63-8b05-6dffa0688028@a26g2000yqn.googlegroups.com>
Message-ID: <028e48c2-4a3a-4920-9a67-d9bb95714b4f@c36g2000yqn.googlegroups.com>

On 16 July, 11:58, Mark <l... at qtrac.plus.com> wrote:
> On 16 July, 08:51, Steven D'Aprano
>
>
>
> <ste... at REMOVE.THIS.cybersource.com.au> wrote:
> > On Thu, 16 Jul 2009 00:30:26 -0700, Chris Rebert wrote:
> > > On Wed, Jul 15, 2009 at 11:21 PM, Mark Summerfield<l... at qtrac.plus.com>
> > > wrote:
> > >> Hi,
>
> > >> I'm just wondering why <, <=, >=, and > are not supported by
> > >> collections.OrderedDict:
>
> > >> ? ?>>> d1 = collections.OrderedDict((("a",1),("z",2),("k",3))) d2 =
> > >> ? ?>>> d1.copy()
> > >> ? ?>>> d2["z"] = 4
> > >> ? ?>>> d1 == d2
> > >> ? ?False
> > >> ? ?>>> d1 < d2
> > >> ? ?Traceback (most recent call last):
> > >> ? ?File "<pyshell#6>", line 1, in <module>
> > >> ? ? ? ?d1 < d2
> > >> ? ?TypeError: unorderable types: OrderedDict() < OrderedDict()
>
> > >> It just seems to me that since the items in ordered dictionaries are
> > >> ordered, it would make sense to do an item by item comparison from
> > >> first to last item in exactly the same way that Python compares lists
> > >> or tuples?
>
> > > Use case? I'm curious.
>
> > Surely it would be the same use case as for comparing two lists? There
> > doesn't need to be a special "OrderedDict use case" beyond "an
> > OrderedDict is just like a list of (key,value) tuples, but searches are
> > faster".
>
> > Or maybe not. If OrderedDicts are sequences as well as mappings, then we
> > should be able to sort them. And that seems a bit much even for me.
>
> > --
> > Steven
>
> One thing that I've just noticed is that you can use <, <=, >=, and >
> with sets:
>
> >>> s1 = {1,2,3}
> >>> s2 = {1,2,4}
> >>> s1 == s2
> False
> >>> s1 < s2
> False
> >>> s1 <= s2
> False
> >>> s2 < s1
> False
> >>> s2 <= s1
> False
> >>> s1 != s2
>
> True
>
> It seems a bit inconsistent that with sets you always get False when
> using an ordering operator but with an ordered dict you get an
> exception?

Ooops---disregard the above---I forgot that these do subset and
superset comparisions!


From akhilanger at gmail.com  Thu Jul 16 07:00:00 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 04:00:00 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <4a5ed587$0$1627$742ec2ed@news.sonic.net>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
Message-ID: <24514309.post@talk.nabble.com>


I have switched to python 3.1 , but now I am getting some syntax errors in
the code:

File "./customWikiExtractor.py", line 81
    __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1',
'&cent;'    :u'\u00A2',
                                            ^
SyntaxError: invalid syntax

line 81 is:
__char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1', '&cent;'   
:u'\u00A2',
                        '&pound;'  :u'\u00A3', '&curren;':u'\u00A4', '&yen;'    
:u'\u00A5',
                        '&brvbar;' :u'\u00A6', '&sect;'  :u'\u00A7', '&uml;'    
:u'\u00A8',
                        '&copy;'   :u'\u00A9', '&ordf;'  :u'\u00AA',
'&laquo;'   :u'\u00AB',
                        '&not;'    :u'\u00AC', '&shy;'   :u'\u00AD', '&reg;'    
:u'\u00AE',
                        '&macr;'   :u'\u00AF', '&deg;'   :u'\u00B0',
'&plusmn;'  :u'\u00B1',
                        '&sup2;'   :u'\u00B2', '&sup3;'  :u'\u00B3',
'&acute;'   :u'\u00B4',
                        '&micro;'  :u'\u00B5', '&para;'  :u'\u00B6',
'&middot;'  :u'\u00B7',
                        '&cedil;'  :u'\u00B8', '&sup1;'  :u'\u00B9',
'&ordm;'    :u'\u00BA',}

--Akhil


John Nagle-2 wrote:
> 
> akhil1988 wrote:
>> Sorry, it is sgmllib.py and not sgmmlib.py
> 
>     Oh, that bug again.  See
> 
> 	http://bugs.python.org/issue1651995
> 
> It's a bug in SGMLParser.  When Python 2.5 restricted ASCII to 0..127,
> SGMLParser needed to be modified, but wasn't.
> 
> I reported that bug in February 2007.  It was fixed in
> Python 2.6 and 3.0 on March 31, 2009.
> 
> 					John Nagle
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24514309.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From user at example.net  Thu Jul 16 07:01:34 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:01:34 +0200
Subject: using timers to force an execution time
In-Reply-To: <7c8fgbF26vgl2U1@mid.uni-berlin.de>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
Message-ID: <4a5f088f$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> What you can't achieve in python without major black magic hackery that is
> very dangerous is to terminate a thread while it is executing. Termination
> has to be co-operative.

i see. thanks a lot.

bye


From deets at nospam.web.de  Thu Jul 16 07:03:55 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:03:55 +0200
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <7c8fgbF26vgl2U1@mid.uni-berlin.de>

superpollo wrote:

> hello.
> 
> based upon previuos suggestions, i tried to write a program in which i
> would like to have a certain code fragment to execute only for a
> specified amount of time (say 3 seconds), then bail out.
> 
> but i get the following:
> 
> $ cat tmr004.py
> #!/usr/bin/python -u
> 
> import threading , time
> 
> e = threading.Event()
> t = threading.Timer(3.0, e.set)
> t.start()
> print time.asctime(time.localtime(time.time()))
> while not e.isSet():
>      for repeat in range(10):
>          print time.time()
>          time.sleep(0.66)
> print time.asctime(time.localtime(time.time()))
> $ ./tmr004.py
> Thu Jul 16 12:31:27 2009
> 1247740287.44
> 1247740288.1
> 1247740288.76
> 1247740289.42
> 1247740290.08
> 1247740290.74
> 1247740291.4
> 1247740292.06
> 1247740292.72
> 1247740293.38
> Thu Jul 16 12:31:34 2009
> $
> 
> see? the while body ran for about 7 seconds... i bet it has to do with
> the fact that the timer does not control inner loops... any suggestion?

Of course the inner loop isn't affected by the set event - how should it be,
if you don't check it.

if you rewrite it as this:

while True:
    for repeat in range(10):
        if e.isSet():
           break
        print time.time()
        time.sleep(.66)

it should terminate earlier.

What you can't achieve in python without major black magic hackery that is
very dangerous is to terminate a thread while it is executing. Termination
has to be co-operative.

Diez


From user at example.net  Thu Jul 16 07:04:08 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:04:08 +0200
Subject: using timers to force an execution time
In-Reply-To: <7c8fgbF26vgl2U1@mid.uni-berlin.de>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
Message-ID: <4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
>>see? the while body ran for about 7 seconds... i bet it has to do with
>>the fact that the timer does not control inner loops... any suggestion?
> 
> 
> Of course the inner loop isn't affected by the set event - how should it be,
> if you don't check it.
> 
> if you rewrite it as this:
> 
> while True:
>     for repeat in range(10):
>         if e.isSet():
>            break
>         print time.time()
>         time.sleep(.66)
> 
> it should terminate earlier.

so it seems almost impossible to allocate a certain amount of time to a 
code fragment *without* somehow rewriting its logic?

am i wrong?

bye


From akhilanger at gmail.com  Thu Jul 16 07:04:24 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 04:04:24 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <24514309.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<24514309.post@talk.nabble.com>
Message-ID: <24514367.post@talk.nabble.com>


Please click reply on the post and then read this reply in the editor.
Actually, some sequences have been replaced to their graphical form when
this post is published. So the python code is being displayed, what actually
it is not.

--Akhil



akhil1988 wrote:
> 
> I have switched to python 3.1 , but now I am getting some syntax errors in
> the code:
> 
> File "./customWikiExtractor.py", line 81
>     __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1',
> '&cent;'    :u'\u00A2',
>                                             ^
> SyntaxError: invalid syntax
> 
> line 81 is:
> __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;' :u'\u00A1', '&cent;'   
> :u'\u00A2',
>                         '&pound;'  :u'\u00A3', '&curren;':u'\u00A4',
> '&yen;'     :u'\u00A5',
>                         '&brvbar;' :u'\u00A6', '&sect;'  :u'\u00A7',
> '&uml;'     :u'\u00A8',
>                         '&copy;'   :u'\u00A9', '&ordf;'  :u'\u00AA',
> '&laquo;'   :u'\u00AB',
>                         '&not;'    :u'\u00AC', '&shy;'   :u'\u00AD',
> '&reg;'     :u'\u00AE',
>                         '&macr;'   :u'\u00AF', '&deg;'   :u'\u00B0',
> '&plusmn;'  :u'\u00B1',
>                         '&sup2;'   :u'\u00B2', '&sup3;'  :u'\u00B3',
> '&acute;'   :u'\u00B4',
>                         '&micro;'  :u'\u00B5', '&para;'  :u'\u00B6',
> '&middot;'  :u'\u00B7',
>                         '&cedil;'  :u'\u00B8', '&sup1;'  :u'\u00B9',
> '&ordm;'    :u'\u00BA',}
> 
> --Akhil
> 
> 
> John Nagle-2 wrote:
>> 
>> akhil1988 wrote:
>>> Sorry, it is sgmllib.py and not sgmmlib.py
>> 
>>     Oh, that bug again.  See
>> 
>> 	http://bugs.python.org/issue1651995
>> 
>> It's a bug in SGMLParser.  When Python 2.5 restricted ASCII to 0..127,
>> SGMLParser needed to be modified, but wasn't.
>> 
>> I reported that bug in February 2007.  It was fixed in
>> Python 2.6 and 3.0 on March 31, 2009.
>> 
>> 					John Nagle
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24514367.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From deets at nospam.web.de  Thu Jul 16 07:08:40 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:08:40 +0200
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
Message-ID: <7c8fp8F26vgl2U2@mid.uni-berlin.de>

Diez B. Roggisch wrote:

> superpollo wrote:
> 
>> hello.
>> 
>> based upon previuos suggestions, i tried to write a program in which i
>> would like to have a certain code fragment to execute only for a
>> specified amount of time (say 3 seconds), then bail out.
>> 
>> but i get the following:
>> 
>> $ cat tmr004.py
>> #!/usr/bin/python -u
>> 
>> import threading , time
>> 
>> e = threading.Event()
>> t = threading.Timer(3.0, e.set)
>> t.start()
>> print time.asctime(time.localtime(time.time()))
>> while not e.isSet():
>>      for repeat in range(10):
>>          print time.time()
>>          time.sleep(0.66)
>> print time.asctime(time.localtime(time.time()))
>> $ ./tmr004.py
>> Thu Jul 16 12:31:27 2009
>> 1247740287.44
>> 1247740288.1
>> 1247740288.76
>> 1247740289.42
>> 1247740290.08
>> 1247740290.74
>> 1247740291.4
>> 1247740292.06
>> 1247740292.72
>> 1247740293.38
>> Thu Jul 16 12:31:34 2009
>> $
>> 
>> see? the while body ran for about 7 seconds... i bet it has to do with
>> the fact that the timer does not control inner loops... any suggestion?
> 
> Of course the inner loop isn't affected by the set event - how should it
> be, if you don't check it.
> 
> if you rewrite it as this:
> 
> while True:
>     for repeat in range(10):
>         if e.isSet():
>            break
>         print time.time()
>         time.sleep(.66)
> 
> it should terminate earlier.

This is of course wrong, remove the outer "while"

Diez


From user at example.net  Thu Jul 16 07:09:24 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:09:24 +0200
Subject: using timers to force an execution time
In-Reply-To: <7c8futF26vgl2U3@mid.uni-berlin.de>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
Message-ID: <4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
>>am i wrong?
> 
> 
> No, you are right, for threads that is. You can try & trick around with the
> trace-functionality of python, and some ctypes-based
> system-thread-module-tricks that are, as mentioned before, black-magic & a
> spinning gatling gun pointed to your very own lower extremities.
> 

OUCH.

> The only reliable way of terminating an asynchronous computation is to use
> processes, since python2.6 that's rather convenient with the
> multiprocessing-module. However, that imposes some limits to what you can
> do.

fair enough.

very helpful indeed.

bye


From deets at nospam.web.de  Thu Jul 16 07:11:41 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:11:41 +0200
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <7c8futF26vgl2U3@mid.uni-berlin.de>

superpollo wrote:

> Diez B. Roggisch wrote:
>> superpollo wrote:
>>>see? the while body ran for about 7 seconds... i bet it has to do with
>>>the fact that the timer does not control inner loops... any suggestion?
>> 
>> 
>> Of course the inner loop isn't affected by the set event - how should it
>> be, if you don't check it.
>> 
>> if you rewrite it as this:
>> 
>> while True:
>>     for repeat in range(10):
>>         if e.isSet():
>>            break
>>         print time.time()
>>         time.sleep(.66)
>> 
>> it should terminate earlier.
> 
> so it seems almost impossible to allocate a certain amount of time to a
> code fragment *without* somehow rewriting its logic?
> 
> am i wrong?

No, you are right, for threads that is. You can try & trick around with the
trace-functionality of python, and some ctypes-based
system-thread-module-tricks that are, as mentioned before, black-magic & a
spinning gatling gun pointed to your very own lower extremities.

The only reliable way of terminating an asynchronous computation is to use
processes, since python2.6 that's rather convenient with the
multiprocessing-module. However, that imposes some limits to what you can
do.

Diez



From deets at nospam.web.de  Thu Jul 16 07:15:04 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 16 Jul 2009 13:15:04 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <7c8g58F26vgl2U4@mid.uni-berlin.de>

superpollo wrote:

> hi there.
> 
> is there a way to dump the content of a turtle window to a file or a
> file object?

Why should I want to dump a turtle? They are very benign creatures, dumping
them is going to hurt them needlessly.

Without a cheek-in-tongue: how are we supposed to know what a"turtle window"
is, how you create it, what features it uses? You need to give more
details, such as the module you are using, on what system that runs and so
forth.

Diez


From user at example.net  Thu Jul 16 07:18:51 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 13:18:51 +0200
Subject: turtle dump
In-Reply-To: <7c8g58F26vgl2U4@mid.uni-berlin.de>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
Message-ID: <4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
> 
> 
>>hi there.
>>
>>is there a way to dump the content of a turtle window to a file or a
>>file object?
> 
> 
> Why should I want to dump a turtle? They are very benign creatures, dumping
> them is going to hurt them needlessly.
> 

lol. ;-) the title was indeed supposed to stir a bit of curiosity upon 
the reader...

> Without a cheek-in-tongue: how are we supposed to know what a"turtle window"
> is, how you create it, what features it uses? You need to give more
> details, such as the module you are using, on what system that runs and so
> forth.

in fact i was looking for a *platform independent* way to draw into a 
graphics file (say, a postscript or a png) using the turtle module. so i 
understand that "dumping a window" is not a good expression... maybe 
"redirecting graphics commands to a file instead of a window"?

bye


From wuwei23 at gmail.com  Thu Jul 16 07:24:30 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 04:24:30 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com> 
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net> 
	<mailman.3213.1247742002.8015.python-list@python.org>
Message-ID: <63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>

On Jul 16, 9:00?pm, akhil1988 <akhilan... at gmail.com> wrote:
> I have switched to python 3.1 , but now I am getting some syntax errors in
> the code:

Python 3.x was a major release that endeavoured to clean up a number
of lingering issues with the language, the upshot being that it isn't
entirely backwards compatible with past versions. Unicode became the
default string type, which is what is causing the error here: the u-
prefix is no longer required (or even allowed).

However, Py3.x _does_ come with a handy tool for automatically
converting Python 2.x code to 3.x, called 2to3. One of the things it
should do is convert Py2.x unicode values into their correct
representation in 3.x.

With any luck, it should be able to convert the code you're using
entirely. Let us know how it goes.


From wuwei23 at gmail.com  Thu Jul 16 07:50:29 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 04:50:29 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it> 
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>

On Jul 16, 9:18?pm, superpollo <u... at example.net> wrote:
> lol. ;-) the title was indeed supposed to stir a bit of curiosity upon
> the reader...

Which isn't really useful when trying to obtain assistance... you want
certainty, not curiosity.

> in fact i was looking for a *platform independent* way to draw into a
> graphics file (say, a postscript or a png) using the turtle module. so i
> understand that "dumping a window" is not a good expression... maybe
> "redirecting graphics commands to a file instead of a window"?

You didn't actually answer Diez question. The turtle module is only a
recent (2.6/3.0) addition to Python and is probably obscure enough not
to have tracked across everyone's radar.

So _if_ you're talking about the standard lib turtle module, you're
not looking to 'dump a window', you're looking to write the contents
of turtle.Canvas to file. Canvas only supports writing to postscript,
so you'll have to do something like this (untested):

import turtle
screen = turtle.Screen()
# go go gadget turtle...
screen._canvas.postscript(file='turtle.ps')

Or it may be open('turtle.ps','w').write(screen._canvas.postscript
())... I couldn't find a definitive answer. Try looking through the Tk
docs, it should be covered there.

Note that this is a postscript _text_ file, so you'll also need to
find something to render it with.

Hope this helps point you in the right direction.


From user at example.net  Thu Jul 16 08:11:07 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 14:11:07 +0200
Subject: turtle dump
In-Reply-To: <77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
Message-ID: <4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>

alex23 wrote:
> On Jul 16, 9:18 pm, superpollo <u... at example.net> wrote:
> 
>>lol. ;-) the title was indeed supposed to stir a bit of curiosity upon
>>the reader...
> 
> 
> Which isn't really useful when trying to obtain assistance... you want
> certainty, not curiosity.
> 

ok. my bad.

> 
>>in fact i was looking for a *platform independent* way to draw into a
>>graphics file (say, a postscript or a png) using the turtle module. so i
>>understand that "dumping a window" is not a good expression... maybe
>>"redirecting graphics commands to a file instead of a window"?
> 
> 
> You didn't actually answer Diez question. The turtle module is only a
> recent (2.6/3.0) addition to Python and is probably obscure enough not
> to have tracked across everyone's radar.
> 

actually i am still using 2.3.4, which means that...

> screen = turtle.Screen()

... is not possible

> 
> Hope this helps point you in the right direction.

it certainly did, tahnks.

bye


From bearophileHUGS at lycos.com  Thu Jul 16 08:22:22 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Thu, 16 Jul 2009 05:22:22 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <267d74e2-97ce-477c-a39b-022fc4f82bd3@i6g2000yqj.googlegroups.com>

Superchicken:
> is there a way to dump the content of a turtle window to a file or a file object?

A possible low-tech solution is to append to a list the sequence of
your plotting commands (using a decorator too, even, something like
the logging decorator), and then save all of them at the end into a
text file :-)

Bye,
bearophile


From piet at cs.uu.nl  Thu Jul 16 08:39:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 14:39:54 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
Message-ID: <m2ocrkvm1x.fsf@cs.uu.nl>

>>>>> mheavner <miheavner at gmail.com> (m) wrote:

>m> I'm using multiprocessing to spawn several subprocesses, each of which
>m> uses a very large data structure (making it impractical to pass it via
>m> pipes / pickling). I need to allocate this structure once when the
>m> process is created and have it remain in memory for the duration of
>m> the process. The way the multiprocessing module is set up, only the
>m> 'run' method runs within the subprocess - so creating a wrapper class
>m> with a constructor that allocates the structure in __init__ will not
>m> work, as far as I know, as this will still be within the parent
>m> process.

>m> If I were working in C/C++, I would declare the variable "static"
>m> within the function body - is there any way with the multiprocessing
>m> module to have persistent data members within subprocesses?

>m> Any ideas??

Your post is not entirely clear. Is `the process' the same as `the
subprocess'? 

Assuming it is, what is the problem? You can create the datastructure
first thing in the run method can't you?

Like this:

from multiprocessing import Process
from time import sleep
from random import random

class MyProcess(Process):

    def __init__(self, number):
        self.number = number
        Process.__init__(self)

    def run(self):
        print "Process %s started" % self.number
        self.data = range(self.number * 100000, (self.number + 1) * 100000)
        self.doit()

    def doit(self):
        for i in range(5):
            sleep(3 * random())
            self.data[i] += i
            print self.data[i]

processes = []
for k in range(10):
    p = MyProcess(k)
    p.start()
    processes.append(p)


for p in processes:
    p.join()

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From albert at spenarnc.xs4all.nl  Thu Jul 16 08:45:27 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 16 Jul 2009 12:45:27 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
Message-ID: <kmvkrr.1hc@spenarnc.xs4all.nl>

In article <h2l36k$q5l$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>
>
>I'm will be teaching a programming class to novices, and I've run
>into a clear conflict between two of the principles I'd like to
>teach: code clarity vs. code reuse.  I'd love your opinion about
>it.
>
<SNIP>
>
>This seemed straightforward enough, until I realized that, to be
>useful to my students in their homework, this _binary_search function
>had to handle the case in which the passed function was monotonically
>decreasing in the specified interval...
>
<SNIP>
>
>Here's the rub: the code above is more general (hence more reusable)
>by virtue of this trick with the sense parameter, but it is also
>a bit harder to understand.
>
>This not an unusual situation.  I find that the processing of
>abstracting out common logic often results in code that is harder
>to read, at least for the uninitiated...

Yes, of course. You're teaching, say, green belt programmers.
Good reusable code requires a fifth dan. You may not be up to it
yourself (no offense intended), let alone your students.

Writing a reusable binary search is a very different assignment
from being able to code/use it in a concrete example.

Their choice must be between *writing* a one-off binary search,
versus *using* a brilliantly code, brilliantly documented
binary search that has been given beforehand.

Even assuming the reusable code is perfect in all sense, reusing may
be more effort than writing from scratch.
Then *you* have to explain them about the benefits of reuse.
(The other benefits, of course.)

>
>I'd love to know your opinions on this.

You're welcome.

>kj

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From __peter__ at web.de  Thu Jul 16 08:46:40 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 16 Jul 2009 14:46:40 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
Message-ID: <h3n7fb$b0h$00$1@news.t-online.com>

superpollo wrote:

> alex23 wrote:
>> On Jul 16, 9:18 pm, superpollo <u... at example.net> wrote:
>> 
>>>lol. ;-) the title was indeed supposed to stir a bit of curiosity upon
>>>the reader...
>> 
>> 
>> Which isn't really useful when trying to obtain assistance... you want
>> certainty, not curiosity.
>> 
> 
> ok. my bad.
> 
>> 
>>>in fact i was looking for a *platform independent* way to draw into a
>>>graphics file (say, a postscript or a png) using the turtle module. so i
>>>understand that "dumping a window" is not a good expression... maybe
>>>"redirecting graphics commands to a file instead of a window"?
>> 
>> 
>> You didn't actually answer Diez question. The turtle module is only a
>> recent (2.6/3.0) addition to Python and is probably obscure enough not
>> to have tracked across everyone's radar.
>> 
> 
> actually i am still using 2.3.4, which means that...
> 
>> screen = turtle.Screen()
> 
> ... is not possible

Tested on 2.4:

>>> import turtle
>>> turtle.reset()
>>> for i in range(4):
...     turtle.forward(50)
...     turtle.right(90)
...
>>> turtle._canvas.postscript(file="tmp.ps")
''

I think the big rewrite has happened in 2.6, so the above should also work 
in 2.3.

Peter



From user at example.net  Thu Jul 16 09:07:26 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 15:07:26 +0200
Subject: turtle dump
In-Reply-To: <h3n7fb$b0h$00$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com>
Message-ID: <4a5f260f$0$18931$4fafbaef@reader2.news.tin.it>

Peter Otten wrote:
> Tested on 2.4:
> 
> 
>>>>import turtle
>>>>turtle.reset()
>>>>for i in range(4):
> 
> ...     turtle.forward(50)
> ...     turtle.right(90)
> ...
> 
>>>>turtle._canvas.postscript(file="tmp.ps")
> 
> ''
> 
> I think the big rewrite has happened in 2.6, so the above should also work 
> in 2.3.
> 
> Peter
> 

mr otten, you are great.

bye


From hartley79 at gmail.com  Thu Jul 16 09:10:35 2009
From: hartley79 at gmail.com (hartley)
Date: Thu, 16 Jul 2009 06:10:35 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>
Message-ID: <a98dfff2-eefb-4fa8-909d-78851e4180fe@y19g2000yqy.googlegroups.com>

/* the first telling */
(...)
/* the third telling */
(...)
/* the third telling */


-
If you had loosened up on the sarcasm I would probably have read what
you wrote more thoroughly instead of just skimming through it. Thanks
for the help, but you should seriously consider doing something with
your patronizing attitude.

HTH,
Hartley


From hartley79 at gmail.com  Thu Jul 16 09:13:09 2009
From: hartley79 at gmail.com (hartley)
Date: Thu, 16 Jul 2009 06:13:09 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>
Message-ID: <0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>

/* the first telling */
(...)
/* the second telling */
(...)
/* the third telling */

-
If you had loosened up on the sarcasm I would probably have read what
you wrote more thoroughly instead of just skimming through it. Thanks
for the help, but you should seriously consider doing something with
your patronizing attitude.

HTH,
Hartley


From albert at spenarnc.xs4all.nl  Thu Jul 16 09:15:59 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 16 Jul 2009 13:15:59 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com> <h2uhcb$blq$1@panix3.panix.com>
	<006eb26f$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2814.1247032175.8015.python-list@python.org>
Message-ID: <kmvm6n.1na@spenarnc.xs4all.nl>

In article <mailman.2814.1247032175.8015.python-list at python.org>,
Dennis Lee Bieber  <wlfraed at ix.netcom.com> wrote:
>On 07 Jul 2009 05:05:12 GMT, Steven D'Aprano
><steve at REMOVE-THIS-cybersource.com.au> declaimed the following in
>gmane.comp.python.general:
>
>> Paraphrasing the Collins Dictionary of Mathematics:
>>
>> opposite sense. Sense is also used to distinguish clockwise and anti-
>> clockwise.
>>
>       Which, I believe, is the only usage I've encountered of it... In
>regards to quantum spin states in such things as Scientific American
>(though that magazine has either gone down hill in the last 30 years, or
>my expectations have gone up... Current issues read like the first years
>of Discover magazine)

I dropped my subscription when power was expressed in multiples
of US hair dryers. (I could calculate that back, and was appalled
by the energy wastage of US hair dryers. ;-) )

>--
>       Wulfraed        Dennis Lee Bieber               KD6MOG

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From matt.dubins at sympatico.ca  Thu Jul 16 09:17:27 2009
From: matt.dubins at sympatico.ca (inkhorn)
Date: Thu, 16 Jul 2009 06:17:27 -0700 (PDT)
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<7x63e1kynt.fsf@ruckus.brouhaha.com>
	<e000d10d-f9f0-48c7-8e64-1cb999c50b39@h8g2000yqm.googlegroups.com>
	<07f46fcd-a3ee-414e-a6d0-ce541f61be39@f33g2000vbm.googlegroups.com> 
	<mailman.3073.1247547957.8015.python-list@python.org>
	<22fa2fe9-899b-407a-8e3c-49f29c86fa59@r33g2000yqn.googlegroups.com>
Message-ID: <b1be8010-d13b-49a4-91df-6dc51969f8c2@q11g2000yqi.googlegroups.com>

Hi all,

This was more a question of programming aesthetics for me than one of
great practical significance.  I was looking to perform a certain
function on files in a directory so long as those files weren't found
in certain standard directories.  In other words, I was using os.walk
() to get multiple root directory strings, and the lists of files in
each directory.  The function was to be performed on those files, so
long as certain terms weren't in the root directory string.

In actuality, I could have stuck with the helper function I created,
but I'm always curious to see how well multiple lines of code can turn
into fewer lines of code in python and retain the same functional
value :)

Matt

On Jul 15, 6:46?am, denis <denis-bz... at t-online.de> wrote:
> Sure, Aho-Corasick is fast for fixedstrings; but without real
> numbers / a concrete goal
>
> > > Matt, how many words are you looking for, in how long a string ?
>
> a simple solution is good enough, satisficing. ?Matt asked "how to
> make that function look nicer?"
> but "nice" has many dimensions -- bicycles are nice for some tasks,
> Ferraris for others.
>
> Bythewayhttp://en.wikipedia.org/wiki/Aho-Corasick_algorithmhas a
> link to a Python implementation,
> alsohttp://en.wikipedia.org/wiki/Worse_is_Betteris fun.



From motoom at xs4all.nl  Thu Jul 16 09:17:47 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Thu, 16 Jul 2009 15:17:47 +0200
Subject: turtle dump
In-Reply-To: <h3n7fb$b0h$00$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com>
Message-ID: <4A5F287B.2000503@xs4all.nl>


I got success with the following code (python 2.6.2):

import turtle
turtle.reset()
for i in range(4):
    turtle.forward(50)
    turtle.right(90)
can=turtle.getscreen().getcanvas()
can.postscript(file="tmp.ps")


-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From miheavner at gmail.com  Thu Jul 16 09:18:43 2009
From: miheavner at gmail.com (mheavner)
Date: Thu, 16 Jul 2009 06:18:43 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
Message-ID: <93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>

On Jul 16, 8:39?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> mheavner <miheav... at gmail.com> (m) wrote:
> >m> I'm using multiprocessing to spawn several subprocesses, each of which
> >m> uses a very large data structure (making it impractical to pass it via
> >m> pipes / pickling). I need to allocate this structure once when the
> >m> process is created and have it remain in memory for the duration of
> >m> the process. The way the multiprocessing module is set up, only the
> >m> 'run' method runs within the subprocess - so creating a wrapper class
> >m> with a constructor that allocates the structure in __init__ will not
> >m> work, as far as I know, as this will still be within the parent
> >m> process.
> >m> If I were working in C/C++, I would declare the variable "static"
> >m> within the function body - is there any way with the multiprocessing
> >m> module to have persistent data members within subprocesses?
> >m> Any ideas??
>
> Your post is not entirely clear. Is `the process' the same as `the
> subprocess'?
>
> Assuming it is, what is the problem? You can create the datastructure
> first thing in the run method can't you?
>
> Like this:
>
> from multiprocessing import Process
> from time import sleep
> from random import random
>
> class MyProcess(Process):
>
> ? ? def __init__(self, number):
> ? ? ? ? self.number = number
> ? ? ? ? Process.__init__(self)
>
> ? ? def run(self):
> ? ? ? ? print "Process %s started" % self.number
> ? ? ? ? self.data = range(self.number * 100000, (self.number + 1) * 100000)
> ? ? ? ? self.doit()
>
> ? ? def doit(self):
> ? ? ? ? for i in range(5):
> ? ? ? ? ? ? sleep(3 * random())
> ? ? ? ? ? ? self.data[i] += i
> ? ? ? ? ? ? print self.data[i]
>
> processes = []
> for k in range(10):
> ? ? p = MyProcess(k)
> ? ? p.start()
> ? ? processes.append(p)
>
> for p in processes:
> ? ? p.join()
>
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

'The process' refers to the subprocess. I could do as you say, load
the data structure each time, but the problem is that takes a
considerable amount of time compared to the the actual computation
with the data it contains. I'm using these processes within a loop as
follows:

         # Don't recreate processes or Queues
         pop1 = Queue()
         pop2 = Queue()
         pop_out = Queue()
         p1 = CudaProcess(0, args=(costf,pop1,pop_out))
         p2 = CudaProcess(1, args=(costf,pop2,pop_out))

         # Main loop
         for i in range(maxiter):
                 print 'ITERATION: '+str(i)
                 if log != None:
                         l = open(log,'a')
                 l.write('Iteration: '+str(i)+'\n')
                 l.close()

                 # Split population in two
                 pop1.putmany(pop[0:len(pop)/2])
                 pop2.putmany(pop[len(pop)/2:len(pop)])

                 # Start two processes
                 if not p1.isAlive():
                         p1.start()
                         print 'started %s'%str(p1.getPid())
                 else:
                         p1.run()
                 if not p2.isAlive():
                         p2.start()
                         print 'started %s'%str(p2.getPid())
                 else:
                         p2.run()
                 .
                 .
                 .

So I'd like to load that data into memory once and keep there as long
as the process is alive (ideally when the subprocess is created,
storing some sort of pointer to it), rather than loading it each time
run is called for a process within the loop. Could be my CudaProcess
class - I'll check out what Diez suggested and post back.


From albert at spenarnc.xs4all.nl  Thu Jul 16 09:19:08 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 16 Jul 2009 13:19:08 GMT
Subject: Clarity vs. code reuse/generality
References: <h2l36k$q5l$1@reader1.panix.com>
	<YPA4m.3147$ze1.970@news-server.bigpond.net.au>
	<006ebea2$0$9711$c3e8da3@news.astraweb.com>
	<CuH4m.3259$ze1.429@news-server.bigpond.net.au>
Message-ID: <kmvmbw.1ot@spenarnc.xs4all.nl>

In article <CuH4m.3259$ze1.429 at news-server.bigpond.net.au>,
Lie Ryan  <lie.1296 at gmail.com> wrote:
>Steven D'Aprano wrote:
>> On Tue, 07 Jul 2009 05:13:28 +0000, Lie Ryan wrote:
>>
>>> When people are fighting over things like `sense`, although sense may
>>> not be strictly wrong dictionary-wise, it smells of something burning...
>>
>> That would be my patience.
>>
>> I can't believe the direction this discussion has taken.
>
>Me neither.
>
>> Anybody sensible
>> would be saying "Oh wow, I've just learned a new meaning to the word,
>> that's great, I'm now less ignorant than I was a minute ago". But oh no,
>> we mustn't use a standard meaning to a word, heaven forbid we disturb
>> people's ignorance by teaching them something new.
>
>A meaning of a word is meaningless if nobody apart the writer
>understands it. The purpose of code is 1) to communicate with the

Exactly. And the OP teaches to scientist. They know sense in that
meaning. Maybe you don't, but that is irrelevant.

<SNIP>

Groetjes Albert.

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From anthony.tolle at gmail.com  Thu Jul 16 09:23:57 2009
From: anthony.tolle at gmail.com (Anthony Tolle)
Date: Thu, 16 Jul 2009 06:23:57 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<ae7da03e-5852-4dbe-b11c-37f4afc32dbe@n11g2000yqb.googlegroups.com> 
	<7x3a8xwjq5.fsf@ruckus.brouhaha.com>
Message-ID: <bbdf5d20-4354-4f9d-ab2e-fbd0b33d8233@h21g2000yqa.googlegroups.com>

On Jul 15, 8:32?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Among other things, that uses quadratic time! ?Why do you want to keep
> popping items from that list instead of iterating through it anyway?
>
> Anyway, I think you wrote something close to this:
> ...

Very true!  I didn't think about the problems with pop().  I was using
it as a shortcut for pulling off the first operand.  I forgot that if
you start with an initial operand of "False", the result will be the
same (0 xor X = X)

While I'm not sure how useful it would be, here's a version of the
first function that returns one of the operands (ala AND and OR),
except in the case where there is an even number of True elements,
where it returns False:

def xor(*operands):
    r, rprime = False, False
    for x in operands:
        xprime = bool(x)
        if rprime:
            if xprime:
                r, rprime = False, False
        else:
            r, rprime = x, xprime
    return r

>>> xor(0, 0)
0
>>> xor(0, 1)
1
>>> xor(1, 0)
1
>>> xor(1, 1)
False
>>> xor(0, 1, 2)
False
>>> xor(0, 1, 2, 3)
3
>>> xor(None, [])
[]


From nick at craig-wood.com  Thu Jul 16 09:29:59 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 16 Jul 2009 08:29:59 -0500
Subject: using timers to force an execution time
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
	<4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <slrnh5u88d.604.nick@irishsea.home.craig-wood.com>

superpollo <user at example.net> wrote:
>  Diez B. Roggisch wrote:
> > superpollo wrote:
> >>am i wrong?
> > 
> > 
> > No, you are right, for threads that is. You can try & trick around with the
> > trace-functionality of python, and some ctypes-based
> > system-thread-module-tricks that are, as mentioned before, black-magic & a
> > spinning gatling gun pointed to your very own lower extremities.
> > 
> 
>  OUCH.
> 
> > The only reliable way of terminating an asynchronous computation is to use
> > processes, since python2.6 that's rather convenient with the
> > multiprocessing-module. However, that imposes some limits to what you can
> > do.
> 
>  fair enough.

Or if you are on unix you can use signals...

It is probably just about acceptable to raise an exception in a signal
handler like this code does.

import signal, os, time

class TimeOut(Exception):
    """Thrown on alarm"""
    pass

def sig_alarm(signum, frame):
    raise TimeOut()

def time_out(t, fn, *args, **kwargs):
    """Calls fn with the args and kwargs returning its result or raising a TimeOut exception if it doesn't complete within t seconds"""

    # Turn alarm off and read old value
    old_alarm = signal.alarm(0)
    # Install new handler remembering old
    old_handler = signal.signal(signal.SIGALRM, sig_alarm)
    # Set the timer going
    signal.alarm(t)

    try:
        rc = fn(*args, **kwargs)
    finally:
        # Restore the old handler
        signal.signal(signal.SIGALRM, old_handler)
        signal.alarm(0)          

def test():
    for repeat in range(10):
        print time.time()
        time.sleep(0.66)

if __name__ == "__main__":
    try:
        time_out(3, test)
    except TimeOut:
        print "timed out"

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From inky788 at gmail.com  Thu Jul 16 09:32:34 2009
From: inky788 at gmail.com (Inky 788)
Date: Thu, 16 Jul 2009 06:32:34 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
Message-ID: <34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>

On Jul 10, 7:35?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> walterbyrd <walterb... at iname.com> writes:
> > I believe Guido himself has said that all indentions should be four
> > spaces - no tabs.
>
> Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
> with a simple imperative::
>
> ? ? Use 4 spaces per indentation level.

That actually sounds pretty weird. "Don't do {foo}. Really, I mean
*really* don't do {foo}. Oh, also, the interpreter allows you to do
{foo}. But don't do it! I mean it!".

Very ... perlish, if you ask me.

I realize that a small portion of the community likes the tabs.
They're sold on the tabs. They like the tabs. But tabs are an archaic
holdover from an era when typewriters had physical tabstops on them.
Actually, after *that* they're a holdover from a program called `make`
whose designers unfortunately decided to use tab "characters" to
prefix commands. The tab is vestigial. Your text editor can treat 4
consecutive spaces as a unit if you wish. Let tabs go away. Stop using
them. If your editor keeps irrationally inserting them, make it stop.


From miheavner at gmail.com  Thu Jul 16 09:32:47 2009
From: miheavner at gmail.com (mheavner)
Date: Thu, 16 Jul 2009 06:32:47 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <d74eebed-7127-4902-8469-a67373994ed3@b15g2000yqd.googlegroups.com>

On Jul 16, 9:18?am, mheavner <miheav... at gmail.com> wrote:
> On Jul 16, 8:39?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>
>
>
> > >>>>> mheavner <miheav... at gmail.com> (m) wrote:
> > >m> I'm using multiprocessing to spawn several subprocesses, each of which
> > >m> uses a very large data structure (making it impractical to pass it via
> > >m> pipes / pickling). I need to allocate this structure once when the
> > >m> process is created and have it remain in memory for the duration of
> > >m> the process. The way the multiprocessing module is set up, only the
> > >m> 'run' method runs within the subprocess - so creating a wrapper class
> > >m> with a constructor that allocates the structure in __init__ will not
> > >m> work, as far as I know, as this will still be within the parent
> > >m> process.
> > >m> If I were working in C/C++, I would declare the variable "static"
> > >m> within the function body - is there any way with the multiprocessing
> > >m> module to have persistent data members within subprocesses?
> > >m> Any ideas??
>
> > Your post is not entirely clear. Is `the process' the same as `the
> > subprocess'?
>
> > Assuming it is, what is the problem? You can create the datastructure
> > first thing in the run method can't you?
>
> > Like this:
>
> > from multiprocessing import Process
> > from time import sleep
> > from random import random
>
> > class MyProcess(Process):
>
> > ? ? def __init__(self, number):
> > ? ? ? ? self.number = number
> > ? ? ? ? Process.__init__(self)
>
> > ? ? def run(self):
> > ? ? ? ? print "Process %s started" % self.number
> > ? ? ? ? self.data = range(self.number * 100000, (self.number + 1) * 100000)
> > ? ? ? ? self.doit()
>
> > ? ? def doit(self):
> > ? ? ? ? for i in range(5):
> > ? ? ? ? ? ? sleep(3 * random())
> > ? ? ? ? ? ? self.data[i] += i
> > ? ? ? ? ? ? print self.data[i]
>
> > processes = []
> > for k in range(10):
> > ? ? p = MyProcess(k)
> > ? ? p.start()
> > ? ? processes.append(p)
>
> > for p in processes:
> > ? ? p.join()
>
> > --
> > Piet van Oostrum <p... at cs.uu.nl>
> > URL:http://pietvanoostrum.com[PGP8DAE142BE17999C4]
> > Private email: p... at vanoostrum.org
>
> 'The process' refers to the subprocess. I could do as you say, load
> the data structure each time, but the problem is that takes a
> considerable amount of time compared to the the actual computation
> with the data it contains. I'm using these processes within a loop as
> follows:
>
> ? ? ? ? ?# Don't recreate processes or Queues
> ? ? ? ? ?pop1 = Queue()
> ? ? ? ? ?pop2 = Queue()
> ? ? ? ? ?pop_out = Queue()
> ? ? ? ? ?p1 = CudaProcess(0, args=(costf,pop1,pop_out))
> ? ? ? ? ?p2 = CudaProcess(1, args=(costf,pop2,pop_out))
>
> ? ? ? ? ?# Main loop
> ? ? ? ? ?for i in range(maxiter):
> ? ? ? ? ? ? ? ? ?print 'ITERATION: '+str(i)
> ? ? ? ? ? ? ? ? ?if log != None:
> ? ? ? ? ? ? ? ? ? ? ? ? ?l = open(log,'a')
> ? ? ? ? ? ? ? ? ?l.write('Iteration: '+str(i)+'\n')
> ? ? ? ? ? ? ? ? ?l.close()
>
> ? ? ? ? ? ? ? ? ?# Split population in two
> ? ? ? ? ? ? ? ? ?pop1.putmany(pop[0:len(pop)/2])
> ? ? ? ? ? ? ? ? ?pop2.putmany(pop[len(pop)/2:len(pop)])
>
> ? ? ? ? ? ? ? ? ?# Start two processes
> ? ? ? ? ? ? ? ? ?if not p1.isAlive():
> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.start()
> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p1.getPid())
> ? ? ? ? ? ? ? ? ?else:
> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.run()
> ? ? ? ? ? ? ? ? ?if not p2.isAlive():
> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.start()
> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p2.getPid())
> ? ? ? ? ? ? ? ? ?else:
> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.run()
> ? ? ? ? ? ? ? ? ?.
> ? ? ? ? ? ? ? ? ?.
> ? ? ? ? ? ? ? ? ?.
>
> So I'd like to load that data into memory once and keep there as long
> as the process is alive (ideally when the subprocess is created,
> storing some sort of pointer to it), rather than loading it each time
> run is called for a process within the loop. Could be my CudaProcess
> class - I'll check out what Diez suggested and post back.

Essentially, I'd like to "sneak" that allocation in somewhere after
the fork is done (in start()) in the context of the subprocess,
holding a pointer to that structure, but before all of the run() calls
are done


From emile at fenx.com  Thu Jul 16 09:34:34 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 06:34:34 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5EEDAE.3040605@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com>
Message-ID: <h3na3s$qjr$1@ger.gmane.org>

On 7/16/2009 2:06 AM Jean-Michel Pichavant said...
> Ok then, why "or" does not return True, if the first element is 
> considered True ? Why returning the element itself. Any reason for that 
> ? Because it's confusing, maybe people used to that logic find it 
> obvious, but I really don't.

For example, I sometimes use it to set defaults:

daysInAdvance = int(inputVar) or 25

Emile



From wuwei23 at gmail.com  Thu Jul 16 09:43:20 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 06:43:20 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it> 
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it> 
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com> 
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
Message-ID: <e0f4708f-1717-4420-8d5b-87b3c1d5a82a@b25g2000prb.googlegroups.com>

On Jul 16, 10:11?pm, superpollo <u... at example.net> wrote:
> actually i am still using 2.3.4, which means that...
>
> > screen = turtle.Screen()
>
> ... is not possible

Ah, sorry about that. My belief that turtle was a new module was based
on a line from http://us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-PyCon2007.pdf

   Since Python 2.6/3.0, Python has had a new turtle module.

At which point I stopped reading and missed the following line:

   Its development was based entirely on the previous one.

In my defence, I _had_ been drinking.

Thankfully Peter stepped up with a more appropriate solution, and
Michiel pointed out the more suitable API calls over dealing directly
with the underlying implementation :) Good work guys!


From p.f.moore at gmail.com  Thu Jul 16 09:46:13 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Thu, 16 Jul 2009 14:46:13 +0100
Subject: using timers to force an execution time
In-Reply-To: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
Message-ID: <79990c6b0907160646n58163a3fx1577951dab64215d@mail.gmail.com>

2009/7/16 superpollo <user at example.net>:
> hello.
>
> based upon previuos suggestions, i tried to write a program in which i would
> like to have a certain code fragment to execute only for a specified amount
> of time (say 3 seconds), then bail out.
>
> but i get the following:
>
> $ cat tmr004.py
> #!/usr/bin/python -u
>
> import threading , time
>
> e = threading.Event()
> t = threading.Timer(3.0, e.set)
> t.start()
> print time.asctime(time.localtime(time.time()))
> while not e.isSet():
> ? ?for repeat in range(10):
> ? ? ? ?print time.time()
> ? ? ? ?time.sleep(0.66)
> print time.asctime(time.localtime(time.time()))
> $ ./tmr004.py
> Thu Jul 16 12:31:27 2009
> 1247740287.44
> 1247740288.1
> 1247740288.76
> 1247740289.42
> 1247740290.08
> 1247740290.74
> 1247740291.4
> 1247740292.06
> 1247740292.72
> 1247740293.38
> Thu Jul 16 12:31:34 2009
> $
>
> see? the while body ran for about 7 seconds... i bet it has to do with the
> fact that the timer does not control inner loops... any suggestion?

Clearly, this isn't what you are actually trying to do. For this case,
your event is getting set when you expect, but your main thread does
not check the event often enough to let it stop in a timely manner.

To fix this, remove the inner "for repeat in range(10)" loop. But I
assume that your "real" code isn't something that you can fix this
easily. If you describe your real requirement, it may be possible to
give you a better answer. (But that answer will almost certainly not
be a way of interrupting one thread from another - that's not really
possible with Python - but rather a way of achieving your goal without
*needing* to interrupt one thread from another).

Paul.

PS If you really must interrupt one thread from another, you can use C
code (or ctypes) to call the PyThreadState_SetAsyncExc API. But I'm
not going to tell you how, as it's almost certainly *not* what you
want to do in practice :-)


From user at example.net  Thu Jul 16 09:46:41 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 15:46:41 +0200
Subject: using timers to force an execution time
In-Reply-To: <slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
	<4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>
	<slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
Message-ID: <4a5f2f43$0$18933$4fafbaef@reader2.news.tin.it>

Nick Craig-Wood wrote:
> superpollo <user at example.net> wrote:
 > ...
> Or if you are on unix you can use signals...
>
> It is probably just about acceptable to raise an exception in a signal
> handler like this code does.
> 
 > ...

neat!


From icanbob at gmail.com  Thu Jul 16 09:50:52 2009
From: icanbob at gmail.com (bobicanprogram)
Date: Thu, 16 Jul 2009 06:50:52 -0700 (PDT)
Subject: Passing handlers between bound c++ libs
References: <3e7b0717-a665-4f42-b7bd-7a99d59258c4@m11g2000yqh.googlegroups.com>
Message-ID: <a61c8b52-8a98-41e0-921e-f3dd5d40e239@k6g2000yqn.googlegroups.com>

On Jul 14, 7:07 pm, Freyr <freyr.magnus... at gmail.com> wrote:
> I have a python bound physics library that uses handler to process
> events. The passing of handlers between c++ and python causes a huge
> overhead slowing down the process.  Can I implement a handler in my
> custom python bound c++ lib B and pass it to blackbox python bound c++
> lib A so that A would call B directly without passing through the
> python layer?  Or to phrase the question differently:  Can I pass a
> handler from B through python to A so that A will invoke B with out
> calling into python code?


Depending on your exact configuration you may be able to wrap that C++
library using the SIMPL toolkit and get at your data with a
message.    There is some "hello world" demo code here:

http://www.icanprogram.com/06py/main.html

bob


From user at example.net  Thu Jul 16 09:51:59 2009
From: user at example.net (superpollo)
Date: Thu, 16 Jul 2009 15:51:59 +0200
Subject: using timers to force an execution time
In-Reply-To: <slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
References: <4a5f022d$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8fgbF26vgl2U1@mid.uni-berlin.de>
	<4a5f0929$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8futF26vgl2U3@mid.uni-berlin.de>
	<4a5f0a64$0$18927$4fafbaef@reader2.news.tin.it>
	<slrnh5u88d.604.nick@irishsea.home.craig-wood.com>
Message-ID: <4a5f3080$0$18933$4fafbaef@reader2.news.tin.it>

Nick Craig-Wood wrote:
 > ...
> import signal, os, time
> ...
importing os is useless of course...


From jeanmichel at sequans.com  Thu Jul 16 09:53:45 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 16 Jul 2009 15:53:45 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3na3s$qjr$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>
	<h3na3s$qjr$1@ger.gmane.org>
Message-ID: <4A5F30E9.1000404@sequans.com>

Emile van Sebille wrote:
> On 7/16/2009 2:06 AM Jean-Michel Pichavant said...
>> Ok then, why "or" does not return True, if the first element is 
>> considered True ? Why returning the element itself. Any reason for 
>> that ? Because it's confusing, maybe people used to that logic find 
>> it obvious, but I really don't.
>
> For example, I sometimes use it to set defaults:
>
> daysInAdvance = int(inputVar) or 25
>
> Emile
>
Sure this looks like an elegant way to set default values and I will use 
this form , but I'm not sure this justifies by itself the trickery. 
Python has extended the algebra definition of "or" and "and" top any 
type, but it is so unintuitive (I'm no LISP programmer). I think than 
using the short-circuiting mechanism of bool operators along with the 
python tricks is just error prone and may result in bug difficult to 
spot, unless you are very aware of all python boolean mechanisms.

JM



From invalid at invalid  Thu Jul 16 10:04:34 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 16 Jul 2009 09:04:34 -0500
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com>
	<mailman.3216.1247751117.8015.python-list@python.org>
Message-ID: <HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>

On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
> On 7/16/2009 2:06 AM Jean-Michel Pichavant said...
>> Ok then, why "or" does not return True, if the first element is 
>> considered True ? Why returning the element itself. Any reason for that 
>> ? Because it's confusing, maybe people used to that logic find it 
>> obvious, but I really don't.
>
> For example, I sometimes use it to set defaults:
>
> daysInAdvance = int(inputVar) or 25

I don't get it.  That doesn't work right when inputVar == "0".

-- 
Grant Edwards                   grante             Yow! What I want to find
                                  at               out is -- do parrots know
                               visi.com            much about Astro-Turf?


From invalid at invalid  Thu Jul 16 10:05:22 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 16 Jul 2009 09:05:22 -0500
Subject: How to search this newsgroup by a python script.
References: <7c897lF26dea4U1@mid.dfncis.de>
	<mailman.3210.1247736812.8015.python-list@python.org>
Message-ID: <HpWdnZdeXqU_rsLXnZ2dnUVZ_qWdnZ2d@posted.visi>

On 2009-07-16, Chris Rebert <clp2 at rebertia.com> wrote:
> On Thu, Jul 16, 2009 at 2:12 AM, Helmut
> Jarausch<jarausch at igpm.rwth-aachen.de> wrote:
>> Hi,
>>
>> I haven't found anything with Google's group search, so let me
>> ask it (again?).
>>
>> How can I search this newsgroup from within a Python script.
>> (Perhaps by searching Google Groups or Gmane by some Python code.)
>
> 1. Generate URL of the form:
> http://search.gmane.org/?query=foo&group=gmane.comp.python.general
> where "foo" is the search terms, with proper URL escaping applied.
> 2. Fetch URL using urllib - http://docs.python.org/library/urllib.html
> 3. Parse resulting HTML page (e.g. using BeautifulSoup)
> 4. Extract desired information from search results using the parse tree.
> 5. ???
> 6. Profit!

The underpants gnomes would be proud.

-- 
Grant Edwards                   grante             Yow! I'm encased in the
                                  at               lining of a pure pork
                               visi.com            sausage!!


From nleioatt at gmail.com  Thu Jul 16 10:07:58 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 16 Jul 2009 07:07:58 -0700 (PDT)
Subject: This is a mess...
Message-ID: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>

I've been coding python for about a week now, and i'm trying to make
an object oriented version of a program i just wrote.  in this post is
the original program.  the next post will include the new programs and
the traceback.  i'm sure there are many underlying problems, but have
been stuck on this for 2 days now...

email me for input files since they are big and i don't see a way to
upload a file here(~5 mB)
this program works, and inputing the same file twice you should get a
"Q" values of ~1 (.99...)

##############CODE#####################

#9July09
#Compute the covariance overlap of two results
#Read in _U.asc files for both ensembles to find e-vectors
#Read in _ .asc files for both ensembles to find sqrt e-values
#strip out matrix info
#compute corvariance


import sys
import math
from math import sqrt


if len(sys.argv) != 3:
    print " "
    print "The corrent usage is 'python covariance.py file1 file2'"
    print "where the _U.asc and _s.asc will be appended when needed"
    print " "
    exit(1)


####Input the first prefix1_U.asc file:
####this is the first eigen vector matrix
prefix1 = sys.argv[1] + "_U.asc"
fileholder = open(prefix1)
text = fileholder.readlines()
fields = text[1].split()
num_rows = int(fields[1])
num_cols = int(fields[2])

U1_matrix = []
for line in text[2: num_rows+2]:
    fields = line.split()
    for i in range(len(fields)):
        fields[i] = float(fields[i])
    U1_matrix.append(fields)

####Input the second prefix2_U.asc file:
####this is the 2nd eigen vector matrix
prefix2 = sys.argv[2] + "_U.asc"
fileholder = open(prefix2)
text = fileholder.readlines()
fields = text[1].split()
num_rows = int(fields[1])
num_cols = int(fields[2])
#print "look here nick:", fields

U2_matrix = []
for line in text[2: num_rows+2]:
    fields = line.split()
    for i in range(len(fields)):
        fields[i] = float(fields[i])
    U2_matrix.append(fields)

####Then Read in the first eigen values
####1st 2 lines are header and need to be stripped away
prefix3 = sys.argv[1] + "_s.asc"
fileholder = open(prefix3)
text = fileholder.readlines()
fields = text[1].split()
num_vals1 = int(fields[1]) #add check to see if correct # of values
added
print "square if", len(U1_matrix), "=", len(U2_matrix), "=", len
(U1_matrix[1]), "=", len(U2_matrix[1])
#the list of sqrt e vals
sqrt_s1 = [float(line) for line in text[2: num_vals1+2]]
s1 = [float(line) * float(line) for line in text[2: num_vals1+2]]

####Finally, read in the 2nd set of eigen vals
prefix4 = sys.argv[2] + "_s.asc"
fileholder = open(prefix4)
text = fileholder.readlines()
fields = text[1].split()
num_vals2 = int(fields[1]) #add check to see if correct # of values
added
#the list of sqrt e vals
sqrt_s2 = [float(line) for line in text[2: num_vals1+2]]
s2 = [float(line) * float(line) for line in text[2: num_vals1+2]]


#=============================================================
####double summation (the 2nd term)
doublesum = 0.0
for i in range(len(U1_matrix[1])):
   #print "i = ", i
    v1 = U1_matrix[i]
    sum = 0
    for j in range(len(U2_matrix)):
         v2 = U2_matrix[j]
         dot = 0
         for k in range(len(U1_matrix)):
             dot += v1[k] * v2[k]
         root = sqrt_s1[i] * sqrt_s2[j]
         sum += root * dot * dot
    doublesum += sum


print "double sum: ", doublesum

####single summation (the 1st term and denominator)
singsum = 0.0
for k in range(len(s1)):
    singsum += s1[k] + s2[k]
print "sing sum:", singsum


####Put it all together
Q = 1 - sqrt(abs((singsum - (2.0*doublesum)) / singsum))
print "your Q:"
print Q

############################# end of code covariance.py



From seldan24 at gmail.com  Thu Jul 16 10:12:24 2009
From: seldan24 at gmail.com (seldan24)
Date: Thu, 16 Jul 2009 07:12:24 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
	<mailman.3175.1247679960.8015.python-list@python.org>
Message-ID: <27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>

On Jul 15, 1:48?pm, Emile van Sebille <em... at fenx.com> wrote:
> On 7/15/2009 10:23 AM MRAB said...
>
> >> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> >>> seldan24 wrote:
> >>>> what can I use as the equivalent for the Unix 'fold' command?
> >>> def fold(s,len):
> >>> ? ? ?while s:
> >>> ? ? ? ? ?print s[:len]
> >>> ? ? ? ? ?s=s[len:]
>
> <snip>
> > You might still need to tweak the above code as regards how line endings
> > are handled.
>
> You might also want to tweak it if the strings are _really_ long to
> simply slice out the substrings as opposed to reassigning the balance to
> a newly created s on each iteration.
>
> Emile

Thanks for all of the help.  I'm almost there.  I have it working now,
but the 'fold' piece is very slow.  When I use the 'fold' command in
shell it is almost instantaneous.  I was able to do the EBCDIC->ASCII
conversion usng the decode method in the built-in str type.  I didn't
have to import the codecs module.  I just decoded the data to cp037
which works fine.

So now, I'm left with a large file, consisting of one extremely long
line of ASCII data that needs to be sliced up into 35 character
lines.  I did the following, which works but takes a very long time:

f = open(ascii_file, 'w')
while ascii_data:
    f.write(ascii_data[:len])
    ascii_data = ascii_data[len:]
f.close()

I know that Emile suggested that I can slice out the substrings rather
than do the gradual trimming of the string variable as is being done
by moving around the length.  So, I'm going to give that a try... I'm
a bit confused by what that means, am guessing that slice can break up
a string based on characters; will research.  Thanks for the help thus
far.  I'll post again when all is working fine.


From aahz at pythoncraft.com  Thu Jul 16 10:14:40 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 07:14:40 -0700
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
Message-ID: <h3nckg$db3$1@panix3.panix.com>

In article <45228cf4-0b37-4c52-bf6f-d7bd124b0f82 at l32g2000vbp.googlegroups.com>,
Tony  Lay  <tonylay at gmail.com> wrote:
>
>Traceback (most recent call last):
>  File "/usr/local/bin/meld", line 35, in <module>
>    import gettext
>  File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
>    import locale, copy, os, re, struct, sys
>  File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
>    import functools
>  File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
>    from _functools import partial, reduce
>ImportError: No module named _functools

Where is _functools.so?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From nleioatt at gmail.com  Thu Jul 16 10:15:52 2009
From: nleioatt at gmail.com (Nick)
Date: Thu, 16 Jul 2009 07:15:52 -0700 (PDT)
Subject: This is a mess...
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
Message-ID: <e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>

this is the new oop version, its pretty messy currently, and i do
understand it is a simple routine, but i'm using it as an exercise to
learn oop python...

first the (current) traceback:
 [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
<Eigen.Eigen_vect instance at 0x7fa26c404ab8>
<Eigen.Eigen_vect instance at 0x7fa26c404ab8>
Traceback (most recent call last):
  File "oop_covariance.py", line 24, in <module>
    cov = set1.covariance(set2, Eigen_vect.dot)
  File "/home/nleioatts/python/Eigen.py", line 66, in covariance
    print self.vectors[i][i]
AttributeError: Eigen_vect instance has no attribute '__getitem__'

and a quick explaination:  the file structures aare a 2d list of lists
of numbers corresponding to eginvectors and a list of numbers
corresponding to eigenvalues

#########################33##Here is the main body
#!/usr/bin/env python
import sys
import Eigen
from Eigen import *

if len(sys.argv) != 3:
    print " "
    print "The corrent usage is 'python covariance.py file1 file2'"
    print "where the _U.asc and _s.asc will be appended when needed"
    print " "
    exit(1)
file1 =  sys.argv[1]
file2 =  sys.argv[2]
set1 = Eigen_set(file1+"_U.asc", file1+"_s.asc")
set2 = Eigen_set(file2+"_U.asc", file2+"_s.asc")
cov = set1.covariance(set2, Eigen_vect.dot)
print cov


###############and here are the classes:

#!/usr/bin/env python
import sys
import math
from math import sqrt

class Eigen_vect:
    def __init__(self, e_val, e_vect):
        self.e_val  = e_val
        self.e_vect = e_vect
    def length(self):
        return len(self.e_vect)

    def dot(self, other):
        d = 0.0
        if other.length() != self.length():
            raise ValueError, "Eigen Vectors not same Length"
        for k in range(self.length()):
           # print "HI NICK", self.e_vect[k], other.e_vect[k]
            d += float(self.e_vect[k]) * float(other.e_vect[k])
        return d


class Eigen_set:
    def __init__(self,  vec_filename, val_filename):
        self.vec_filename = vec_filename
        self.val_filename = val_filename
        # open two files
        # loop through them, skipping lines that begin with #
        # for each row, extract eigen vector and eigen values
        fileholder = open(self.vec_filename)
        text = fileholder.readlines()
        fields = text[2].split()
#        print "len of fields", len(fields)
        self.vectors = []
        for line in text[2: len(fields)]:
            fields = line.split()
#            print "len of fields", len(fields)
            for i in range(len(fields)):
                fields[i] = float(fields[i])
        e_vect = fields
        fileholder = open(self.val_filename)
        text = fileholder.readlines()
        e_val = [float(line) for line in text[2: self.length()]]
        self.vectors.append(Eigen_vect(e_val, e_vect))
#        print "this is self.vectors"
#        print self.vectors(e_val)

    def length(self):
        return len(self.vectors)

    def covariance(self, other, dot):
        newdot = 0.0
        # do a length check to make sure we're consistent
        if other.length() != self.length():
            raise ValueError, "Eigen Vectors not same Length"
        #double loop over all my vectors and all of other's vectors
        doublesum = 0.0
        for i in range(self.length()):
            sum = 0.0
            v1 = self.vectors[i]
            for j in range(self.length()):
                newdot += v1.dot(self.vectors[j])
               # root = self.e_val[i] * other.e_val[j]
                print self.vectors[i]
                print self.vectors[j]
                print self.vectors[i][i]
#####################<<------------------------This is line 66, I'm
trying to figure out how to call "e_val" from the Eigen_set class

                root = self.vectors[i][i] * other.vectors[i][j]
                sum  += newdot * newdot * root
            doublesum += sum
        #########
        singsum = 0.0
        for k in range(self.length()):
            singsum += self.e_val[k] * self.e_val[k] + other.e_val[k]
* other.e_val[k]
        Q = 1 - sqrt(abs((singsum - (2.0*doublesum)) / singsum))
        print "your Q:"
        print Q



and any additional help is great.  thanks in advance, like the title
says this is really a mess....


From python.list at tim.thechases.com  Thu Jul 16 10:18:47 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 16 Jul 2009 09:18:47 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
Message-ID: <4A5F36C7.5010307@tim.thechases.com>

> I realize that a small portion of the community likes the tabs.
> They're sold on the tabs. They like the tabs. But tabs are an archaic
> holdover from an era when typewriters had physical tabstops on them.

However, they are a single logical level of indentation -- I come 
down fairly solidly on the "tabs" side of the "tabs vs. spaces" 
argument.  I can set my editor (vim in this case) to show tabs as 
as many spaces as I want.  I usually have this set to 4, but 
sometimes 1 or 2.  In Vim, using tabs I can just switch up my 
tab-stop setting (":set ts=2") and the presentation of my code 
reindents the way I expect.  If I wanted to switch from 
4-real-spaces to 2-real-spaces, I'd have to concoct a perlish 
regexp to handle the munging.

The same "separation of content and presentation" that is all the 
rage with N-tier programmers and web developers, my content is 
"logical levels of indentation indicated by a tab character in 
the source-code" and my presentation is "N spaces as presented by 
my editor".

Yes, the dictatorial "a tab always equals 8 spaces" is a 
vestigial holdover for which I hold no love.

I'll code on other people's projects with spaces if that's the 
project convention (as Vim lets me switch around fairly easily). 
  But as for my own code, it's tabs all the way.

-tkc





From sjmachin at lexicon.net  Thu Jul 16 10:20:25 2009
From: sjmachin at lexicon.net (John Machin)
Date: Thu, 16 Jul 2009 07:20:25 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<9ad398aa-c68e-48a0-951c-fb10a0e27da1@l35g2000pra.googlegroups.com> 
	<51203b20-f38e-4629-94b8-2427cd453652@f30g2000vbf.googlegroups.com> 
	<cd6c612a-8f32-4927-8198-060c3461bf95@x25g2000prf.googlegroups.com> 
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com> 
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>
Message-ID: <e4bff690-895e-438f-a8eb-3b5c0f0857bc@t11g2000prh.googlegroups.com>

On Jul 16, 11:13?pm, hartley <hartle... at gmail.com> wrote:
> /* the first telling */
> (...)
> /* the second telling */
> (...)
> /* the third telling */
>
> -
> If you had loosened up on the sarcasm

That wasn't sarcasm, it was an attempt at humourous watering-down the
expression of exasperation at continued ignoring of advice and wonder
that I was continuing to bother ...

> HTH,

It didn't.


From aahz at pythoncraft.com  Thu Jul 16 10:22:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 07:22:16 -0700
Subject: Memory leak involving traceback objects
References: <e6e9b9ea-1f8c-4695-90da-72e85c8a63e4@v20g2000yqm.googlegroups.com>
Message-ID: <h3nd2o$ipb$1@panix3.panix.com>

In article <e6e9b9ea-1f8c-4695-90da-72e85c8a63e4 at v20g2000yqm.googlegroups.com>,
Rotem  <vmalloc at gmail.com> wrote:
>
>I'm debugging a nasty memory leak in a framework written in Python
>(v2.6.2).
>After much digging around I found that the entire object group that is
>leaking is held by a frame object which is subsequently held by a
>traceback object.
>
>Traversing the get_referrers() of each traceback frame leads
>eventually to a root traceback frame which has no referrers
>(gc.get_referrers returns an empty list).
>
>However, this traceback object seems not to be picked by the garbage
>collector, and is still there even after many iterations and calls to
>gc.collect(). The code location to which the traceback frame points
>doesn't do anything special - it just catches an exception, without
>saving the exception itself and/or traceback anywhere.

What *does* it do?  Does it re-raise?  This sounds like you're still in
block scope of an exception.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From ifl2009 at shu.edu  Thu Jul 16 10:28:44 2009
From: ifl2009 at shu.edu (IFL 2009)
Date: Thu, 16 Jul 2009 10:28:44 -0400
Subject: IFL 2009: Third Call for Papers
Message-ID: <OF46D7ACB1.F2493CBB-ON852575F5.004F88EE-852575F5.004F88F0@shu.edu>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/4416808b/attachment-0001.html>

From james at agentultra.com  Thu Jul 16 10:49:54 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 16 Jul 2009 10:49:54 -0400
Subject: interactive fiction in Python?
References: <5c97224b-99d4-469b-90cb-1c04b1e1e9a0@m11g2000yqh.googlegroups.com>
Message-ID: <853a8wlm25.fsf@agentultra.com>

George Oliver <georgeoliverGO at gmail.com> writes:

> hi, I'm just curious who might be working on interactive fiction
> modules in the style of Inform or TADS for Python. I've seen a few
> threads on this list [1] (among many that mention IF tangentially),
> and there are old projects like PUB and PAWS. There are some newer
> potential projects such as Curveship as well. In any case I'd like to
> see what's out there.

I'd be interested in checking out such a project, but I don't really see
the point in starting one.  There are already several great IF tools out
there that are already freely available!  The only reason I would see to
start one is either for pure intellectual curiosity or because you have
some feature ideas that no one else has implemented (and you'd rather
cash in on the potential glory than submit a patch!).

Best of luck finding what you're looking for... but maybe you should
start writing one yourself and post here about it! :)

Cheers

>
>
> thanks, George
>
>
> [1]:
>
> http://bit.ly/Python_Text_Adventure_Authoring_System
>
> http://bit.ly/simple_interactive_fiction_engine
>
> http://bit.ly/adventure_engines_in_Python


From james at agentultra.com  Thu Jul 16 10:51:47 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 16 Jul 2009 10:51:47 -0400
Subject: Ann: Google releases Python-based open-source NX server
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
Message-ID: <85y6qok7ek.fsf@agentultra.com>

jkn <jkn_gg at nicorp.f9.co.uk> writes:

> Google quietly releases open-source NX server ...written in Python,
> apparently
>
> <http://www.computerworld.com/s/article/9135504/
> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>
> Neatx can be downloaded from Google's code repository:
>
> <http://code.google.com/p/neatx/>
>
>     Regards
>     J^n

It's pretty cool, but not PEP8! Probably because they just bought the
source off of another smaller proprietary project.  Makes me sad seeing
Google, proud supporter of all things Python, release non-PEP8 code.

Either way, I did check out the project and it looks pretty exciting.
Hopefully I'll get some time to contribute a few patches.


From gabriel.rossetti at arimaz.com  Thu Jul 16 11:12:23 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Thu, 16 Jul 2009 17:12:23 +0200
Subject: no return value for threading.Condition.wait(timeout)?
Message-ID: <4A5F4357.5060402@arimaz.com>

Hello everyone,

I am using threading.Condition.wait(timeout) and was surprised to see 
that there is no return value nor an exception when wait() is used w/ a 
timeout. How am I supposed to know if it was notified or if it timed out?

cheers,
Gabriel


From maxerickson at gmail.com  Thu Jul 16 11:31:36 2009
From: maxerickson at gmail.com (Max Erickson)
Date: Thu, 16 Jul 2009 15:31:36 +0000 (UTC)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<24514309.post@talk.nabble.com> <24514367.post@talk.nabble.com>
Message-ID: <Xns9C4A753E9B41maxericksongmailcom@80.91.229.13>

akhil1988 <akhilanger at gmail.com> wrote:

> 
> akhil1988 wrote:
>> 
>> I have switched to python 3.1 , but now I am getting some syntax
>> errors in the code:
>> 
>> File "./customWikiExtractor.py", line 81
>>     __char_entities =  {'&nbsp;'   :u'\u00A0', '&iexcl;'
>>     :u'\u00A1', 
>> '&cent;'    :u'\u00A2',
>>                                             ^

You may want to try 2.6. Python 3.1 is not syntax compatible with 2.5 
(so the u'' stuff won't work in 3.1):

http://docs.python.org/dev/py3k/whatsnew/3.0.html#removed-syntax



max



From motoom at xs4all.nl  Thu Jul 16 11:34:25 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Thu, 16 Jul 2009 17:34:25 +0200
Subject: Python Equivalent for dd & fold
In-Reply-To: <27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>	<4A5E1082.8090901@mrabarnett.plus.com>	<mailman.3175.1247679960.8015.python-list@python.org>
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <4A5F4881.9090501@xs4all.nl>

seldan24 wrote:

> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length. 

An excellent idea.

def fold(s,chunklength):
     offset=0
     while offset<len(s):
         print s[offset:offset+chunklength]
         offset+=chunklength

s="A very long string indeed. Really that long? Indeed."
fold(s,10)


-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From sjmachin at lexicon.net  Thu Jul 16 11:43:41 2009
From: sjmachin at lexicon.net (John Machin)
Date: Thu, 16 Jul 2009 08:43:41 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7' 
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com> 
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net> 
	<24514309.post@talk.nabble.com>
	<mailman.3214.1247742266.8015.python-list@python.org>
Message-ID: <dfb3a911-152c-4895-a266-c498d4e8e632@u16g2000pru.googlegroups.com>

On Jul 16, 9:04?pm, akhil1988 <akhilan... at gmail.com> wrote:
> Please click reply on the post and then read this reply in the editor.
> Actually, some sequences have been replaced to their graphical form when
> this post is published. So the python code is being displayed, what actually
> it is not.

What editor? I guess you mean that somebody's browser may be
interpreting the & blah ; thingies .... but this is not relevant; your
syntax error problem is that 2.x unicode literals have a u in front
but 3.x str literals don't IOW you need to lose the first u in
u'\u00A0'


From Caseyweb at gmail.com  Thu Jul 16 11:44:18 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Thu, 16 Jul 2009 08:44:18 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
	<mailman.3175.1247679960.8015.python-list@python.org> 
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <26e55904-58b6-482f-a2b6-c6edfb5bf32e@y4g2000prf.googlegroups.com>

On Jul 16, 10:12?am, seldan24 <selda... at gmail.com> wrote:
> On Jul 15, 1:48?pm, Emile van Sebille <em... at fenx.com> wrote:
>
>
>
> > On 7/15/2009 10:23 AM MRAB said...
>
> > >> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> > >>> seldan24 wrote:
> > >>>> what can I use as the equivalent for the Unix 'fold' command?
> > >>> def fold(s,len):
> > >>> ? ? ?while s:
> > >>> ? ? ? ? ?print s[:len]
> > >>> ? ? ? ? ?s=s[len:]
>
> > <snip>
> > > You might still need to tweak the above code as regards how line endings
> > > are handled.
>
> > You might also want to tweak it if the strings are _really_ long to
> > simply slice out the substrings as opposed to reassigning the balance to
> > a newly created s on each iteration.
>
> > Emile
>
> Thanks for all of the help. ?I'm almost there. ?I have it working now,
> but the 'fold' piece is very slow. ?When I use the 'fold' command in
> shell it is almost instantaneous. ?I was able to do the EBCDIC->ASCII
> conversion usng the decode method in the built-in str type. ?I didn't
> have to import the codecs module. ?I just decoded the data to cp037
> which works fine.
>
> So now, I'm left with a large file, consisting of one extremely long
> line of ASCII data that needs to be sliced up into 35 character
> lines. ?I did the following, which works but takes a very long time:
>
> f = open(ascii_file, 'w')
> while ascii_data:
> ? ? f.write(ascii_data[:len])
> ? ? ascii_data = ascii_data[len:]
> f.close()
>
> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length. ?So, I'm going to give that a try... I'm
> a bit confused by what that means, am guessing that slice can break up
> a string based on characters; will research. ?Thanks for the help thus
> far. ?I'll post again when all is working fine.

The problem is that it creates a new string every time you iterate
through the "ascii_data = ascii_data[len:]".  I believe Emile was
suggesting that you just keep moving the starting index through the
same string, something like (warning - untested code!):

>>> i = 0
>>> str_len = len(ascii_data)
>>> while i < str_len:
>>>     j = min(i + length, str_len)
>>>     print ascii_data[i:j]
>>>     i = j


From pdpinheiro at gmail.com  Thu Jul 16 12:02:25 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Thu, 16 Jul 2009 09:02:25 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
	<4A5E1082.8090901@mrabarnett.plus.com>
	<mailman.3175.1247679960.8015.python-list@python.org> 
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <4592d512-592b-4e58-829e-e643be34bcec@r33g2000yqn.googlegroups.com>

On Jul 16, 3:12?pm, seldan24 <selda... at gmail.com> wrote:
> On Jul 15, 1:48?pm, Emile van Sebille <em... at fenx.com> wrote:
>
>
>
>
>
> > On 7/15/2009 10:23 AM MRAB said...
>
> > >> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
> > >>> seldan24 wrote:
> > >>>> what can I use as the equivalent for the Unix 'fold' command?
> > >>> def fold(s,len):
> > >>> ? ? ?while s:
> > >>> ? ? ? ? ?print s[:len]
> > >>> ? ? ? ? ?s=s[len:]
>
> > <snip>
> > > You might still need to tweak the above code as regards how line endings
> > > are handled.
>
> > You might also want to tweak it if the strings are _really_ long to
> > simply slice out the substrings as opposed to reassigning the balance to
> > a newly created s on each iteration.
>
> > Emile
>
> Thanks for all of the help. ?I'm almost there. ?I have it working now,
> but the 'fold' piece is very slow. ?When I use the 'fold' command in
> shell it is almost instantaneous. ?I was able to do the EBCDIC->ASCII
> conversion usng the decode method in the built-in str type. ?I didn't
> have to import the codecs module. ?I just decoded the data to cp037
> which works fine.
>
> So now, I'm left with a large file, consisting of one extremely long
> line of ASCII data that needs to be sliced up into 35 character
> lines. ?I did the following, which works but takes a very long time:
>
> f = open(ascii_file, 'w')
> while ascii_data:
> ? ? f.write(ascii_data[:len])
> ? ? ascii_data = ascii_data[len:]
> f.close()
>
> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length. ?So, I'm going to give that a try... I'm
> a bit confused by what that means, am guessing that slice can break up
> a string based on characters; will research. ?Thanks for the help thus
> far. ?I'll post again when all is working fine.

Assuming your rather large text file is 1 meg long, you have 1 million
characters in there. 1000000/35 = ~29k lines. The size remaining
string decreases linearly, so the average size is (1000000 + 0) / 2 or
500k. All said and done, you're allocating and copying a 500K string
-- not once, but 29 thousand times. That's where your slowdown resides.


From tn.pablo at gmail.com  Thu Jul 16 12:02:57 2009
From: tn.pablo at gmail.com (Pablo Torres N.)
Date: Thu, 16 Jul 2009 11:02:57 -0500
Subject: How to check if any item from a list of strings is in a big 
	string?
In-Reply-To: <pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>
Message-ID: <fdd00b510907160902o1707d07dv4eec1a3e1144c6f1@mail.gmail.com>

On Thu, Jul 9, 2009 at 22:07, Steven
D'Aprano<steven at remove.this.cybersource.com.au> wrote:
> On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:
>
>> def list_items_in_string(list_items, string):
>> ? ? for item in list_items:
>> ? ? ? ? if item in string:
>> ? ? ? ? ? ? return True
>> ? ? return False
> ...
>> Any ideas how to make that function look nicer? :)
>
> Change the names. Reverse the order of the arguments. Add a docstring.
>

Why reverse the order of the arguments? Is there a design principle there?

I always make a mess out of the order of my arguments...

-- 
Pablo Torres N.


From degibb at gmail.com  Thu Jul 16 12:15:46 2009
From: degibb at gmail.com (David Gibb)
Date: Thu, 16 Jul 2009 12:15:46 -0400
Subject: list of all possible values
In-Reply-To: <8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>
References: <mailman.3054.1247502101.8015.python-list@python.org>
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
	<8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>
Message-ID: <ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com>

> Certainly possible with list comprehensions.
>
>>>> a = "abc"
>>>> [(x, y) for x in a for y in a]
> [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b', 'c'),
> ('c', 'a'), ('c', 'b'), ('c', 'c')]
>
> But I like bearophile's version better.
>

Andreas,

Thanks, but I think you were missing my point. I should have explained better.

The advantage that bearophile's version is generic with respect to the
number of elements in each combination. To go from 2 element pairs
(e.g. ('a', 'c')) to 5 element pairs (e.g. ('a', 'c', 'b', 'b', 'e'))
requires only a change in a parameter passed to itertools.

I don't see how you would do that with list comprehensions. You're
example works nicely with 2 element pairs, but it seems to me like
you'd need to recode it if you wanted to change it to 5 element pairs.

Am I wrong about that? Can you think of a way to write a function
that, using list comprehensions, takes a list of values and the size
of each combination, and returns the len(list)**(combination size)
possible combinations using those values?

Thanks again,
David


From rylesny at gmail.com  Thu Jul 16 12:23:25 2009
From: rylesny at gmail.com (ryles)
Date: Thu, 16 Jul 2009 09:23:25 -0700 (PDT)
Subject: Python Equivalent for dd & fold
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>
	<mailman.3171.1247676439.8015.python-list@python.org>
	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>
Message-ID: <a3835950-195f-4857-9688-4768fe1fe1f7@l28g2000vba.googlegroups.com>

On Jul 15, 1:14?pm, seldan24 <selda... at gmail.com> wrote:
> On Jul 15, 12:47?pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>
>
>
> > seldan24 wrote:
> > > what can I use as the equivalent for the Unix 'fold' command?
>
> > def fold(s,len):
> > ? ? ?while s:
> > ? ? ? ? ?print s[:len]
> > ? ? ? ? ?s=s[len:]
>
> > s="A very long string indeed. Really that long? Indeed."
> > fold(s,10)
>
> > Output:
>
> > A very lon
> > g string i
> > ndeed. Rea
> > lly that l
> > ong? Indee
> > d.
>
> > Greetings,
>
> > --
> > "The ability of the OSS process to collect and harness
> > the collective IQ of thousands of individuals across
> > the Internet is simply amazing." - Vinod Valloppillilhttp://www.catb.org/~esr/halloween/halloween4.html
>
> Wow, I feel like a dork. ?I should have done more research prior to
> posting. ?Anyway, thanks for the advice. ?The trouble with Python is
> that things make 'too much' sense. ?Loving this language.

You might also find the textwrap module useful:

http://docs.python.org/library/textwrap.html


From emile at fenx.com  Thu Jul 16 12:23:43 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 09:23:43 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<mailman.3216.1247751117.8015.python-list@python.org>
	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
Message-ID: <h3nk10$tvu$1@ger.gmane.org>

On 7/16/2009 7:04 AM Unknown said...
> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
>> daysInAdvance = int(inputVar) or 25
> 
> I don't get it.  That doesn't work right when inputVar == "0".
> 
Aah, but you didn't get to define right.  :)  For that particular 
example 0 is not a valid response.

Emile



From jeanmichel at sequans.com  Thu Jul 16 12:37:45 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 16 Jul 2009 18:37:45 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <h3nk10$tvu$1@ger.gmane.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<mailman.3216.1247751117.8015.python-list@python.org>	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
	<h3nk10$tvu$1@ger.gmane.org>
Message-ID: <4A5F5759.4010600@sequans.com>

Emile van Sebille wrote:
> On 7/16/2009 7:04 AM Unknown said...
>> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
>>> daysInAdvance = int(inputVar) or 25
>>
>> I don't get it.  That doesn't work right when inputVar == "0".
>>
> Aah, but you didn't get to define right.  :)  For that particular 
> example 0 is not a valid response.
>
> Emile
>
When I was talking about such error prone form of boolean operations, I 
didn't expect to be right so quickly :p
Steven explained the truth notion with the Something/Nothing. "0" is 
Something, 0 would be Nothing. I'm not sure it makes sens anyway. I 
mean, I could easily argue that the number 0 is something. In the end I 
wonder if I shouldn't just acknowledge the python mechanism without 
trying to find any intuitive/natural/obvious logic in it, knowing that 
sometimes the Truth lies far away from the Evidence.

JM


From andreas.tawn at ubisoft.com  Thu Jul 16 12:49:11 2009
From: andreas.tawn at ubisoft.com (Andreas Tawn)
Date: Thu, 16 Jul 2009 18:49:11 +0200
Subject: list of all possible values
In-Reply-To: <ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com>
References: <mailman.3054.1247502101.8015.python-list@python.org>
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com>
	<8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org>
	<ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com>
Message-ID: <8AEDA5E3386EA742B8C24C95FF0C7580079FCD7C@PDC-MAIL3.ubisoft.org>

> > Certainly possible with list comprehensions.
> >
> >>>> a = "abc"
> >>>> [(x, y) for x in a for y in a]
> > [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
'c'),
> > ('c', 'a'), ('c', 'b'), ('c', 'c')]
> >
> > But I like bearophile's version better.
> >
> 
> Andreas,
> 
> Thanks, but I think you were missing my point. I should have explained
better.
> 
> The advantage that bearophile's version is generic with respect to the
> number of elements in each combination. To go from 2 element pairs
> (e.g. ('a', 'c')) to 5 element pairs (e.g. ('a', 'c', 'b', 'b', 'e'))
> requires only a change in a parameter passed to itertools.
> 
> I don't see how you would do that with list comprehensions. You're
> example works nicely with 2 element pairs, but it seems to me like
> you'd need to recode it if you wanted to change it to 5 element pairs.
> 
> Am I wrong about that? Can you think of a way to write a function
> that, using list comprehensions, takes a list of values and the size
> of each combination, and returns the len(list)**(combination size)
> possible combinations using those values?
> 
> Thanks again,
> David

David,

I think my post got caught in the nebulous email eddys and seems to have
taken 16 hours to arrive on the list. It was meant to be a reply to your
first post, not your second.

Having said that, I think I missed the point of that post too ;o)

Maybe someone smarter than me can come up with a way to dynamically nest
the fors in a list comprehension, but I certainly can't do it.

Sorry for the confusion.

Cheers,

Drea


From python at mrabarnett.plus.com  Thu Jul 16 13:06:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 16 Jul 2009 18:06:09 +0100
Subject: Python Equivalent for dd & fold
In-Reply-To: <27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>	<4A5E1082.8090901@mrabarnett.plus.com>	<mailman.3175.1247679960.8015.python-list@python.org>
	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
Message-ID: <4A5F5E01.1060505@mrabarnett.plus.com>

seldan24 wrote:
> On Jul 15, 1:48 pm, Emile van Sebille <em... at fenx.com> wrote:
>> On 7/15/2009 10:23 AM MRAB said...
>>
>>>> On Jul 15, 12:47 pm, Michiel Overtoom <mot... at xs4all.nl> wrote:
>>>>> seldan24 wrote:
>>>>>> what can I use as the equivalent for the Unix 'fold' command?
>>>>> def fold(s,len):
>>>>>      while s:
>>>>>          print s[:len]
>>>>>          s=s[len:]
>> <snip>
>>> You might still need to tweak the above code as regards how line endings
>>> are handled.
>> You might also want to tweak it if the strings are _really_ long to
>> simply slice out the substrings as opposed to reassigning the balance to
>> a newly created s on each iteration.
>>
>> Emile
> 
> Thanks for all of the help.  I'm almost there.  I have it working now,
> but the 'fold' piece is very slow.  When I use the 'fold' command in
> shell it is almost instantaneous.  I was able to do the EBCDIC->ASCII
> conversion usng the decode method in the built-in str type.  I didn't
> have to import the codecs module.  I just decoded the data to cp037
> which works fine.
> 
> So now, I'm left with a large file, consisting of one extremely long
> line of ASCII data that needs to be sliced up into 35 character
> lines.  I did the following, which works but takes a very long time:
> 
> f = open(ascii_file, 'w')
> while ascii_data:
>     f.write(ascii_data[:len])
>     ascii_data = ascii_data[len:]
> f.close()
> 
The 'write' method doesn't append any line ending, so that code gives
the same output as f.write(ascii_data).

> I know that Emile suggested that I can slice out the substrings rather
> than do the gradual trimming of the string variable as is being done
> by moving around the length.  So, I'm going to give that a try... I'm
> a bit confused by what that means, am guessing that slice can break up
> a string based on characters; will research.  Thanks for the help thus
> far.  I'll post again when all is working fine.



From python at mrabarnett.plus.com  Thu Jul 16 13:07:54 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 16 Jul 2009 18:07:54 +0100
Subject: Python Equivalent for dd & fold
In-Reply-To: <4A5F4881.9090501@xs4all.nl>
References: <e9dba4a0-6142-439a-b82f-ebf83d7db2a0@l2g2000vba.googlegroups.com>	<mailman.3171.1247676439.8015.python-list@python.org>	<e0453846-59fa-4d5b-9098-e7670219813a@v2g2000vbb.googlegroups.com>	<4A5E1082.8090901@mrabarnett.plus.com>	<mailman.3175.1247679960.8015.python-list@python.org>	<27f11d7d-2724-4108-b005-04b2fc8cf030@f10g2000vbf.googlegroups.com>
	<4A5F4881.9090501@xs4all.nl>
Message-ID: <4A5F5E6A.60104@mrabarnett.plus.com>

Michiel Overtoom wrote:
> seldan24 wrote:
> 
>> I know that Emile suggested that I can slice out the substrings rather
>> than do the gradual trimming of the string variable as is being done
>> by moving around the length. 
> 
> An excellent idea.
> 
> def fold(s,chunklength):
>     offset=0
>     while offset<len(s):
>         print s[offset:offset+chunklength]
>         offset+=chunklength
> 
More Pythonic:

     for offset in range(0, len(s), chunklength):
         print s[offset : offset + chunklength]

> s="A very long string indeed. Really that long? Indeed."
> fold(s,10)
> 



From piet at cs.uu.nl  Thu Jul 16 13:18:04 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 19:18:04 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <m2hbxcv96b.fsf@cs.uu.nl>

>>>>> mheavner <miheavner at gmail.com> (m) wrote:

>m> 'The process' refers to the subprocess. I could do as you say, load
>m> the data structure each time, but the problem is that takes a
>m> considerable amount of time compared to the the actual computation
>m> with the data it contains. I'm using these processes within a loop as
>m> follows:

>m>          # Don't recreate processes or Queues
>m>          pop1 = Queue()
>m>          pop2 = Queue()
>m>          pop_out = Queue()
>m>          p1 = CudaProcess(0, args=(costf,pop1,pop_out))
>m>          p2 = CudaProcess(1, args=(costf,pop2,pop_out))

>m>          # Main loop
>m>          for i in range(maxiter):
>m>                  print 'ITERATION: '+str(i)
>m>                  if log != None:
>m>                          l = open(log,'a')
>m>                  l.write('Iteration: '+str(i)+'\n')
>m>                  l.close()

>m>                  # Split population in two
>m>                  pop1.putmany(pop[0:len(pop)/2])
>m>                  pop2.putmany(pop[len(pop)/2:len(pop)])

>m>                  # Start two processes
>m>                  if not p1.isAlive():
>m>                          p1.start()
>m>                          print 'started %s'%str(p1.getPid())
>m>                  else:
>m>                          p1.run()

That won't work. p1.run() will execute the run method in the Master
process, not in the subprocess. And if it would your could would have a
race condition: between the p1.isAlive() (which must be is_alive btw), and
the p1.run() the process can have stopped.

The proper way to do is to put the work in a Queue and let the processes
get work out of the Queue. The datastructure will remain in the process
then. 

>m>                  if not p2.isAlive():
>m>                          p2.start()
>m>                          print 'started %s'%str(p2.getPid())
>m>                  else:
>m>                          p2.run()
>m>                  .
>m>                  .
>m>                  .

>m> So I'd like to load that data into memory once and keep there as long
>m> as the process is alive (ideally when the subprocess is created,
>m> storing some sort of pointer to it), rather than loading it each time
>m> run is called for a process within the loop. Could be my CudaProcess
>m> class - I'll check out what Diez suggested and post back.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From miheavner at gmail.com  Thu Jul 16 13:37:45 2009
From: miheavner at gmail.com (mheavner)
Date: Thu, 16 Jul 2009 10:37:45 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
	<m2hbxcv96b.fsf@cs.uu.nl>
Message-ID: <2b61ef2d-4bf6-47ba-824d-6b490a342edb@n11g2000yqb.googlegroups.com>

I realize that the Queue would be the best way of doing this, however
that involves transferring the huge amount of data for each call - my
hope was to transfer it once and have it remain in memory for the
subprocess across run() calls.

On Jul 16, 1:18?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> mheavner <miheav... at gmail.com> (m) wrote:
> >m> 'The process' refers to the subprocess. I could do as you say, load
> >m> the data structure each time, but the problem is that takes a
> >m> considerable amount of time compared to the the actual computation
> >m> with the data it contains. I'm using these processes within a loop as
> >m> follows:
> >m> ? ? ? ? ?# Don't recreate processes or Queues
> >m> ? ? ? ? ?pop1 = Queue()
> >m> ? ? ? ? ?pop2 = Queue()
> >m> ? ? ? ? ?pop_out = Queue()
> >m> ? ? ? ? ?p1 = CudaProcess(0, args=(costf,pop1,pop_out))
> >m> ? ? ? ? ?p2 = CudaProcess(1, args=(costf,pop2,pop_out))
> >m> ? ? ? ? ?# Main loop
> >m> ? ? ? ? ?for i in range(maxiter):
> >m> ? ? ? ? ? ? ? ? ?print 'ITERATION: '+str(i)
> >m> ? ? ? ? ? ? ? ? ?if log != None:
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?l = open(log,'a')
> >m> ? ? ? ? ? ? ? ? ?l.write('Iteration: '+str(i)+'\n')
> >m> ? ? ? ? ? ? ? ? ?l.close()
> >m> ? ? ? ? ? ? ? ? ?# Split population in two
> >m> ? ? ? ? ? ? ? ? ?pop1.putmany(pop[0:len(pop)/2])
> >m> ? ? ? ? ? ? ? ? ?pop2.putmany(pop[len(pop)/2:len(pop)])
> >m> ? ? ? ? ? ? ? ? ?# Start two processes
> >m> ? ? ? ? ? ? ? ? ?if not p1.isAlive():
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.start()
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p1.getPid())
> >m> ? ? ? ? ? ? ? ? ?else:
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p1.run()
>
> That won't work. p1.run() will execute the run method in the Master
> process, not in the subprocess. And if it would your could would have a
> race condition: between the p1.isAlive() (which must be is_alive btw), and
> the p1.run() the process can have stopped.
>
> The proper way to do is to put the work in a Queue and let the processes
> get work out of the Queue. The datastructure will remain in the process
> then.
>
> >m> ? ? ? ? ? ? ? ? ?if not p2.isAlive():
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.start()
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?print 'started %s'%str(p2.getPid())
> >m> ? ? ? ? ? ? ? ? ?else:
> >m> ? ? ? ? ? ? ? ? ? ? ? ? ?p2.run()
> >m> ? ? ? ? ? ? ? ? ?.
> >m> ? ? ? ? ? ? ? ? ?.
> >m> ? ? ? ? ? ? ? ? ?.
> >m> So I'd like to load that data into memory once and keep there as long
> >m> as the process is alive (ideally when the subprocess is created,
> >m> storing some sort of pointer to it), rather than loading it each time
> >m> run is called for a process within the loop. Could be my CudaProcess
> >m> class - I'll check out what Diez suggested and post back.
>
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org



From inky788 at gmail.com  Thu Jul 16 13:47:07 2009
From: inky788 at gmail.com (Inky 788)
Date: Thu, 16 Jul 2009 10:47:07 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
	<mailman.3219.1247753940.8015.python-list@python.org>
Message-ID: <68dbe005-64bc-42f8-99b7-e73c41d0dbd4@r33g2000yqn.googlegroups.com>

On Jul 16, 10:18?am, Tim Chase <python.l... at tim.thechases.com> wrote:
> > I realize that a small portion of the community likes the tabs.
> > They're sold on the tabs. They like the tabs. But tabs are an archaic
> > holdover from an era when typewriters had physical tabstops on them.
>
> However, they are a single logical level of indentation -- I come
> down fairly solidly on the "tabs" side of the "tabs vs. spaces"
> argument.

My bet is that the problem is this: some people like to format their
code in ways that don't work well when you're using tabs. For example,
they might want to call a function like this (note spaces):

some_func(foo=1,
          bar=2,
          baz=3)

instead of:

some_func(
    foo=1,
    bar=2,
    baz=3)

The first one requires 10 spaces in front of bar and baz. If you're
using tabs, that means one or two tabs plus some space characters. So,
people who do that would probably never use tabs. The 2nd example is
fine for tabs or spaces. I'm sure there are a bunch of similar
examples for things besides function calls. Don't you ever find cases
where you'd like to add in an extra space or two to make things line
up nicely?

>?I can set my editor (vim in this case) to show tabs as
> as many spaces as I want. ?I usually have this set to 4, but
> sometimes 1 or 2.

Just curious: why would you want to do that? In my experience, once my
eyes got used to 4-space indents, everything else looks either too
little or too much. :)


From jkn_gg at nicorp.f9.co.uk  Thu Jul 16 13:59:12 2009
From: jkn_gg at nicorp.f9.co.uk (jkn)
Date: Thu, 16 Jul 2009 10:59:12 -0700 (PDT)
Subject: Ann: Google releases Python-based open-source NX server
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
	<85y6qok7ek.fsf@agentultra.com>
Message-ID: <4086976f-11da-4da2-869a-7720510f2bae@m11g2000yqh.googlegroups.com>

On Jul 16, 3:51?pm, J Kenneth King <ja... at agentultra.com> wrote:

> It's pretty cool, but not PEP8! Probably because they just bought the
> source off of another smaller proprietary project. ?Makes me sad seeing
> Google, proud supporter of all things Python, release non-PEP8 code.

Personally, I don't follow PEP8 either. Note: PEP-8 gives 'coding
conventions for the Python code **comprising the standard library in
the main Python distribution**' (my emphasis). My coding conventions
are similar to, but not exactly the same as, PEP-8. It would be
ridiculous IMO (and PEP-8 acknowledges this) for such a permissive
language as Python to put a 'coding style' straitjacket around itself.

YMMV, of course.

    J^n



From emile at fenx.com  Thu Jul 16 14:27:55 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 11:27:55 -0700
Subject: Ann: Google releases Python-based open-source NX server
In-Reply-To: <4086976f-11da-4da2-869a-7720510f2bae@m11g2000yqh.googlegroups.com>
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>	<85y6qok7ek.fsf@agentultra.com>
	<4086976f-11da-4da2-869a-7720510f2bae@m11g2000yqh.googlegroups.com>
Message-ID: <h3nr9t$mig$1@ger.gmane.org>

On 7/16/2009 10:59 AM jkn said...
> Personally, I don't follow PEP8 either. Note: PEP-8 gives 'coding
> conventions for the Python code **comprising the standard library in
> the main Python distribution**' (my emphasis). My coding conventions
> are similar to, but not exactly the same as, PEP-8. 

Mine too, and my objection to PEP-8 is that the coding style doesn't 
allow for copy-n-paste into the interpreter, and I like to be able to 
test that way.  Perhaps if I configured my editor not to strip trailing 
whitespace from lines it would work, but then I don't like trailing 
whitespace.

Of course, I _like_ leading whitespace.  :)

Emile



From robert.kern at gmail.com  Thu Jul 16 14:29:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 16 Jul 2009 13:29:31 -0500
Subject: Ann: Google releases Python-based open-source NX server
In-Reply-To: <85y6qok7ek.fsf@agentultra.com>
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
	<85y6qok7ek.fsf@agentultra.com>
Message-ID: <h3nrib$mq6$1@ger.gmane.org>

On 2009-07-16 09:51, J Kenneth King wrote:
> jkn<jkn_gg at nicorp.f9.co.uk>  writes:
>
>> Google quietly releases open-source NX server ...written in Python,
>> apparently
>>
>> <http://www.computerworld.com/s/article/9135504/
>> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>>
>> Neatx can be downloaded from Google's code repository:
>>
>> <http://code.google.com/p/neatx/>
>>
>>      Regards
>>      J^n
>
> It's pretty cool, but not PEP8! Probably because they just bought the
> source off of another smaller proprietary project.

No, it' just that Google does not use PEP8 for its internal style standard.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python.list at tim.thechases.com  Thu Jul 16 14:40:09 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 16 Jul 2009 13:40:09 -0500
Subject: Why not enforce four space indentations in version 3.x?
In-Reply-To: <68dbe005-64bc-42f8-99b7-e73c41d0dbd4@r33g2000yqn.googlegroups.com>
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>	<87ljmwm7ri.fsf@benfinney.id.au>	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>	<mailman.3219.1247753940.8015.python-list@python.org>
	<68dbe005-64bc-42f8-99b7-e73c41d0dbd4@r33g2000yqn.googlegroups.com>
Message-ID: <4A5F7409.8000502@tim.thechases.com>

>> However, they are a single logical level of indentation -- I come
>> down fairly solidly on the "tabs" side of the "tabs vs. spaces"
>> argument.
> 
> My bet is that the problem is this: some people like to format their
> code in ways that don't work well when you're using tabs. For example,
> they might want to call a function like this (note spaces):
> 
> some_func(foo=1,
>           bar=2,
>           baz=3)
> 
> instead of:
> 
> some_func(
>     foo=1,
>     bar=2,
>     baz=3)

For continued indenting statements such as this, I tend to use 
the coding convention used at my first job out of college 
(Computer Sciences Corp...for better or worse) which just indents 
two levels:

   def some_func(foo=1,
   <tab><tab>bar=2,
   <tab><tab>baz=3):
   <tab>do_something(foo)
   <tab>do_other_stuff(bar)

> examples for things besides function calls. Don't you ever find cases
> where you'd like to add in an extra space or two to make things line
> up nicely?

I have occasionally (okay, "very rarely") use the "mixed 
tab+space" method of indentation for continued lines if I want 
them lined up nicely:

   <tab><tab>if (foo == bar and
   <tab><tab>    baz > frob and
   <tab><tab>    fred != barney):
   <tab><tab><tab>do_something()
   <tab><tab><tab>do_more()

This scheme insures that the visual alignment for the 
continued-line matches up, even if the tab-stop is changed.  The 
positioning of the indented block (the do_* bit) floats 
inconveniently with relation to the continued text, with pessimal 
cases being indistinguishable from the continued lines (which is 
why I generally opt not to use this unless it has great benefits 
in code clarity).  By regularly indenting continued lines for 
containing blocks (if, while, etc) by two tabs, the continuation 
stands out from the contained code regardless of my tab stops.

>>  I can set my editor (vim in this case) to show tabs as
>> as many spaces as I want.  I usually have this set to 4, but
>> sometimes 1 or 2.
> 
> Just curious: why would you want to do that? In my experience, once my
> eyes got used to 4-space indents, everything else looks either too
> little or too much. :)

It totally depends on the project -- I like the condensed nature 
of 2sp/tab for code sharing on mailing lists (and tend to copy 
out of vim with tabs expanded to 2 spaces for pasting into 
emails) and for my own visual preference.  If it's code that I'd 
expect anybody else to view, I tend to use 4sp/tab to keep my 
lines below 80 chars per line with the tabs taken into consideration.

I guess I change up my indent enough that sometimes 2 seems just 
right or too small, and sometimes 4 seems just right or too large.

-tkc






From pavlovevidence at gmail.com  Thu Jul 16 14:45:38 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 16 Jul 2009 11:45:38 -0700 (PDT)
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
Message-ID: <c7ba5d6e-28a5-4c0f-b764-636476634ae8@t13g2000yqt.googlegroups.com>

On Jul 16, 6:32?am, Inky 788 <inky... at gmail.com> wrote:
> On Jul 10, 7:35?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
>
> > walterbyrd <walterb... at iname.com> writes:
> > > I believe Guido himself has said that all indentions should be four
> > > spaces - no tabs.
>
> > Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
> > with a simple imperative::
>
> > ? ? Use 4 spaces per indentation level.
>
> That actually sounds pretty weird. "Don't do {foo}. Really, I mean
> *really* don't do {foo}. Oh, also, the interpreter allows you to do
> {foo}. But don't do it! I mean it!".
>
> Very ... perlish, if you ask me.

Not Perlish at all.

(Perl would never want you not to use something.)


Carl Banks


From tjreedy at udel.edu  Thu Jul 16 14:50:41 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 14:50:41 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <d3da1b04-0ebb-47a0-88aa-8d214cbf774b@24g2000yqm.googlegroups.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>	<mailman.3202.1247728343.8015.python-list@python.org>	<9fc93aa9-13dd-4e9a-9e93-820c65cdb592@o15g2000yqm.googlegroups.com>	<m2zlb5ugnh.fsf@cs.uu.nl>
	<d3da1b04-0ebb-47a0-88aa-8d214cbf774b@24g2000yqm.googlegroups.com>
Message-ID: <h3nsq2$rp4$1@ger.gmane.org>

Mark wrote:
> On 16 July, 10:21, Piet van Oostrum <p... at cs.uu.nl> wrote:

>> But why should the order be as if the OrderedDict was a list of tuples.
>> A dict can be considered as a mapping and then you might want to treat
>> either the key or the value as contravariant (the key I guess). So there
>> is ambiguity. Why would the view as a list of tuples for the ordering be
>> the `natural' view?
>>
>> Maybe you may expect some kind of monotonicity such that d1<d2 implies
>> d1[x]<d2[x], but that doesn't work for d1 = {1:10, 2:20} and d2 = {1:15,
>> 2:5}. So maybe there is only a partial ordering?
> 
> OK, that seems to me to be a convincing argument against supporting
> ordering.

To put the above in a slightly different way. OrderedDicts are a 
recently added niche class that Raymond added to what is mostly his 
collections module because there are enough few use cases. There was 
pydev discussion which included the idea, I believe, that they should 
fundamentally be dicts, not lists. Regardless, the justifying use cases 
did not include a need to compare OrderedDicts. The small fraction of 
the few use cases for OrderedDicts that do require comparision can be 
met by extracting the needed sequences and comparing *them* in the 
appropriate manner. The 'appropriate manner' is not likely to always be 
the same. This point may have come up in the discussion, but I would let 
you check for sure if curious.

'Consistency' is a Python design principle, but it is balanced with 
others, so that it is not sufficient reason to add nearly useless 
features. There is a cost to every addition.

Terry Jan Reedy



From akhilanger at gmail.com  Thu Jul 16 14:57:09 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 11:57:09 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
Message-ID: <24522412.post@talk.nabble.com>


Hi,

Thanks all for the replies.

I am working on a cluster of 15 nodes and I have now installed python 3.1 on
all of them. I tried installing python2.6 but there was some make error. So,
I do not want to give more time in installing 2.4  and rather use 3.1 but
for that I need to convert my 2.4 code to 3.1. 

I used 2to3 tool, and it did make many changes in the 2.4 code, but still
there are some indentation errors that I am unable to resolve being new to
python. I have attached my python code, can anyone please fix the
indentation error in the code. I am using vi editor.

--Thanks a lot,
Akhil http://www.nabble.com/file/p24522412/temp.py temp.py 


alex23 wrote:
> 
> On Jul 16, 9:00?pm, akhil1988 <akhilan... at gmail.com> wrote:
>> I have switched to python 3.1 , but now I am getting some syntax errors
>> in
>> the code:
> 
> Python 3.x was a major release that endeavoured to clean up a number
> of lingering issues with the language, the upshot being that it isn't
> entirely backwards compatible with past versions. Unicode became the
> default string type, which is what is causing the error here: the u-
> prefix is no longer required (or even allowed).
> 
> However, Py3.x _does_ come with a handy tool for automatically
> converting Python 2.x code to 3.x, called 2to3. One of the things it
> should do is convert Py2.x unicode values into their correct
> representation in 3.x.
> 
> With any luck, it should be able to convert the code you're using
> entirely. Let us know how it goes.
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24522412.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From 1x7y2z9 at gmail.com  Thu Jul 16 15:02:52 2009
From: 1x7y2z9 at gmail.com (1x7y2z9)
Date: Thu, 16 Jul 2009 12:02:52 -0700 (PDT)
Subject: URLError errno and strerror not set
Message-ID: <5bbbf0b7-743d-48bc-bd0d-67a6626a58cd@z4g2000prh.googlegroups.com>


python 2.5.2

errno, strerror and message do not appear to be set in the following
two cases (at least).
Is this to be expected?  (as an aside, arg[0] is set)

# case 1
> print exception, exception.errno, exception.strerror, exception.message == ''
<urlopen error (111, 'Connection refused')> None None True

# case 2
> print exception, exception.errno, exception.strerror, exception.message == ''
<urlopen error timed out> None None True

Thanks.


From piet at cs.uu.nl  Thu Jul 16 15:10:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 21:10:08 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
	<m2hbxcv96b.fsf@cs.uu.nl>
	<2b61ef2d-4bf6-47ba-824d-6b490a342edb@n11g2000yqb.googlegroups.com>
Message-ID: <m2d480v3zj.fsf@cs.uu.nl>

>>>>> mheavner <miheavner at gmail.com> (m) wrote:

>m> I realize that the Queue would be the best way of doing this, however
>m> that involves transferring the huge amount of data for each call - my
>m> hope was to transfer it once and have it remain in memory for the
>m> subprocess across run() calls.

Which huge amount of data? The datastructure you talked about can remain
in the process. You only have to transfer the input for your calculation
in the queue but you have to do that anyway. And there is only one run
call per process. When run has terminated the process exits, so you
would have a loop in the run(0 method getting work from the queue.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Thu Jul 16 15:26:02 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 12:26:02 -0700
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com>
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com>
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>
Message-ID: <h3nusa$pcb$1@panix3.panix.com>

In article <0afc5c4d-1af5-4d0e-9442-26b51b12e5b4 at m11g2000yqh.googlegroups.com>,
hartley  <hartley79 at gmail.com> wrote:
>
>If you had loosened up on the sarcasm I would probably have read what
>you wrote more thoroughly instead of just skimming through it. Thanks
>for the help, but you should seriously consider doing something with
>your patronizing attitude.

http://www.mikeash.com/getting_answers.html
http://www.catb.org/~esr/faqs/smart-questions.html
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From james at agentultra.com  Thu Jul 16 15:36:11 2009
From: james at agentultra.com (J Kenneth King)
Date: Thu, 16 Jul 2009 15:36:11 -0400
Subject: Ann: Google releases Python-based open-source NX server
References: <42cd7043-58b7-4472-a149-9dc03bc169d3@y7g2000yqa.googlegroups.com>
	<85y6qok7ek.fsf@agentultra.com>
	<mailman.3232.1247768985.8015.python-list@python.org>
Message-ID: <85r5wgju8k.fsf@agentultra.com>

Robert Kern <robert.kern at gmail.com> writes:

> On 2009-07-16 09:51, J Kenneth King wrote:
>> jkn<jkn_gg at nicorp.f9.co.uk>  writes:
>>
>>> Google quietly releases open-source NX server ...written in Python,
>>> apparently
>>>
>>> <http://www.computerworld.com/s/article/9135504/
>>> Google_quietly_releases_open_source_NX_server?taxonomyId=88>
>>>
>>> Neatx can be downloaded from Google's code repository:
>>>
>>> <http://code.google.com/p/neatx/>
>>>
>>>      Regards
>>>      J^n
>>
>> It's pretty cool, but not PEP8! Probably because they just bought the
>> source off of another smaller proprietary project.
>
> No, it' just that Google does not use PEP8 for its internal style standard.

Yeah probably.

I'm just a little OCD sometimes.


From akhilanger at gmail.com  Thu Jul 16 15:41:40 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 12:41:40 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7'  in position 13: ordinal not in range(128)
In-Reply-To: <24522412.post@talk.nabble.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com>
Message-ID: <24523113.post@talk.nabble.com>


ok!
I got the indentation errors fixed. Bu I get another error:

Traceback (most recent call last):
  File "./temp.py", line 484, in <module>
    main()
  File "./temp.py", line 476, in main
    line.decode('utf-8').strip()
AttributeError: 'str' object has no attribute 'decode'

I am using Python3.1

Thanks
Akhil




akhil1988 wrote:
> 
> Hi,
> 
> Thanks all for the replies.
> 
> I am working on a cluster of 15 nodes and I have now installed python 3.1
> on all of them. I tried installing python2.6 but there was some make
> error. So, I do not want to give more time in installing 2.4  and rather
> use 3.1 but for that I need to convert my 2.4 code to 3.1. 
> 
> I used 2to3 tool, and it did make many changes in the 2.4 code, but still
> there are some indentation errors that I am unable to resolve being new to
> python. I have attached my python code, can anyone please fix the
> indentation error in the code. I am using vi editor.
> 
> --Thanks a lot,
> Akhil http://www.nabble.com/file/p24522412/temp.py temp.py 
> 
> 
> alex23 wrote:
>> 
>> On Jul 16, 9:00?pm, akhil1988 <akhilan... at gmail.com> wrote:
>>> I have switched to python 3.1 , but now I am getting some syntax errors
>>> in
>>> the code:
>> 
>> Python 3.x was a major release that endeavoured to clean up a number
>> of lingering issues with the language, the upshot being that it isn't
>> entirely backwards compatible with past versions. Unicode became the
>> default string type, which is what is causing the error here: the u-
>> prefix is no longer required (or even allowed).
>> 
>> However, Py3.x _does_ come with a handy tool for automatically
>> converting Python 2.x code to 3.x, called 2to3. One of the things it
>> should do is convert Py2.x unicode values into their correct
>> representation in 3.x.
>> 
>> With any luck, it should be able to convert the code you're using
>> entirely. Let us know how it goes.
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
>> 
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24523113.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From tonylay at gmail.com  Thu Jul 16 15:45:27 2009
From: tonylay at gmail.com (Tony Lay)
Date: Thu, 16 Jul 2009 12:45:27 -0700 (PDT)
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
	<h3nckg$db3$1@panix3.panix.com>
Message-ID: <df40bd48-7028-4348-8c35-4491c89e2abe@f33g2000vbm.googlegroups.com>

On Jul 16, 10:14?am, a... at pythoncraft.com (Aahz) wrote:
> In article <45228cf4-0b37-4c52-bf6f-d7bd124b0... at l32g2000vbp.googlegroups.com>,
> Tony ?Lay ?<tony... at gmail.com> wrote:
>
>
>
> >Traceback (most recent call last):
> > ?File "/usr/local/bin/meld", line 35, in <module>
> > ? ?import gettext
> > ?File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
> > ? ?import locale, copy, os, re, struct, sys
> > ?File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
> > ? ?import functools
> > ?File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
> > ? ?from _functools import partial, reduce
> >ImportError: No module named _functools
>
> Where is _functools.so?
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "If you think it's expensive to hire a professional to do the job, wait
> until you hire an amateur." ?--Red Adair

/usr/local/lib/python2.6/lib-dynload/

It's in the path...
export PYTHONHOME=/usr/local/lib/python2.6
export PYTHONPATH=/usr/local/lib/python2.6:/usr/local/lib/python2.6/
site-packages:/usr/local/lib/python2.6/lib-dynload:/usr/local/etc/
pango


From tonylay at gmail.com  Thu Jul 16 15:56:31 2009
From: tonylay at gmail.com (Tony Lay)
Date: Thu, 16 Jul 2009 12:56:31 -0700 (PDT)
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
	<h3nckg$db3$1@panix3.panix.com>
Message-ID: <bfd28485-adaf-43ca-963d-3576c1c2cd4e@l2g2000vba.googlegroups.com>

On Jul 16, 10:14?am, a... at pythoncraft.com (Aahz) wrote:
> In article <45228cf4-0b37-4c52-bf6f-d7bd124b0... at l32g2000vbp.googlegroups.com>,
> Tony ?Lay ?<tony... at gmail.com> wrote:
>
>
>
> >Traceback (most recent call last):
> > ?File "/usr/local/bin/meld", line 35, in <module>
> > ? ?import gettext
> > ?File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
> > ? ?import locale, copy, os, re, struct, sys
> > ?File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
> > ? ?import functools
> > ?File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
> > ? ?from _functools import partial, reduce
> >ImportError: No module named _functools
>
> Where is _functools.so?
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "If you think it's expensive to hire a professional to do the job, wait
> until you hire an amateur." ?--Red Adair

/usr/local/lib/python2.6/lib-dynload/

It's in the path...
export PYTHONHOME=/usr/local/lib/python2.6
export PYTHONPATH=/usr/local/lib/python2.6:/usr/local/lib/python2.6/
site-packages:/usr/local/lib/python2.6/lib-dynload:/usr/local/etc/
pango


From kyrie at uh.cu  Thu Jul 16 15:57:02 2009
From: kyrie at uh.cu (Luis Alberto Zarrabeitia Gomez)
Date: Thu, 16 Jul 2009 15:57:02 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5F5759.4010600@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com>
	<mailman.3216.1247751117.8015.python-list@python.org>
	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>
	<h3nk10$tvu$1@ger.gmane.org> <4A5F5759.4010600@sequans.com>
Message-ID: <1247774222.4a5f860ec3cfa@mail.uh.cu>


Quoting Jean-Michel Pichavant <jeanmichel at sequans.com>:

> Emile van Sebille wrote:
> > On 7/16/2009 7:04 AM Unknown said...
> >> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
> >>> daysInAdvance = int(inputVar) or 25
> >>
> >> I don't get it.  That doesn't work right when inputVar == "0".
> >>
> > Aah, but you didn't get to define right.  :)  For that particular 
> > example 0 is not a valid response.
>
> When I was talking about such error prone form of boolean operations, I 
> didn't expect to be right so quickly :p

What do you mean by being "right so quickly", and "error prone" in this context?
I would also ask "Unknown" why he believes that "int(intputVar) or 25" doesn't
work right when inputVar == "0". The only false value that int() may return is
zero, so the "or 25" clause is there only for that case. I can't see then how
you think that is an error.

> I'm not sure it makes sens anyway. I 
> mean, I could easily argue that the number 0 is something. In the end I 
> wonder if I shouldn't just acknowledge the python mechanism 

Then look it another way. The "Empty/Nothing" is just standard practice, there
is nothing in python that forces you to be "false" if you are empty, or true
otherwise. Instead, answer this: why do you need a /boolean/ value? Is there any
case where you need to be certain that the object's type is 'bool'? If you think
the answer is "yes", you may want to get more familiar with the "duck typing"
concept. (That doesn't mean that there are no legitimate cases where duck typing
is inappropriate, but that there are many cases where people, specially if they
come from statically typed languages, may believe that it is inappropriate when
it isn't).

In the python world, one should care more about how an object /behaves/ than
from what clase it came. If something quacks like a duck, then assume that it is
a duck, at least for the quacking part.

Most python objects carry a truth value. Sometimes it feels natural (None is
"false", boolean True and False are "true" and "false", empty containers are
expected to be false, 0 and '' are "false"). Sometimes, it is everything but
natural, but that's a problem with the object's implementation (datetime.time
comes to mind). So, you shouldn't care if you have a bool instance - it should
be enough that it behaves like a bool (though, if you need a bool, you can
always construct one). The "True or False" expression could return Giraffes, as
long as Giraffes behave like the bool "True" in boolean context. If you care
about the class of the result, you can ask for its truth value, and if you don't
care about it, you can just ignore it, and use it as you would use a bool.

And then, if you can return any object as long as it behaves properly, what
would be better to return? A new bool? Why not new Giraffe, if they will have
the same behaviour? Guido chose to return the a value that will say more about
the result of the operation than just a boolean. It acts as a boolean - if you
don't need anything else, treat it as such -, but it will be, whenever is
possible, one of the objects in the sequence, in case you need more info.

> without 
> trying to find any intuitive/natural/obvious logic in it, knowing that 
> sometimes the Truth lies far away from the Evidence.

Don't do that. Many of python's decisions are very well thought. You may
disagree with them, as I do with some, but they are rarely taken lightly. And
this is one that I find very agreeable and in line with the rest of python's
philosophy.

-- 
Luis Zarrabeitia
Facultad de Matem?tica y Computaci?n, UH
http://profesores.matcom.uh.cu/~kyrie



-- 
Participe en Universidad 2010, del 8 al 12 de febrero de 2010
La Habana, Cuba 
http://www.universidad2010.cu



From piet at cs.uu.nl  Thu Jul 16 16:01:22 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 16 Jul 2009 22:01:22 +0200
Subject: This is a mess...
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
	<e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
Message-ID: <m263dsv1m5.fsf@cs.uu.nl>

>>>>> Nick <nleioatt at gmail.com> (N) wrote:

>N> this is the new oop version, its pretty messy currently, and i do
>N> understand it is a simple routine, but i'm using it as an exercise to
>N> learn oop python...

>N> first the (current) traceback:
>N>  [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
>N> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
>N> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
>N> Traceback (most recent call last):
>N>   File "oop_covariance.py", line 24, in <module>
>N>     cov = set1.covariance(set2, Eigen_vect.dot)
>N>   File "/home/nleioatts/python/Eigen.py", line 66, in covariance
>N>     print self.vectors[i][i]
>N> AttributeError: Eigen_vect instance has no attribute '__getitem__'

self.vectors is a list of Eigen_vect objects. So self.vectors[i] is an
Eigen_vect object. Now you do a subscript on this Eigen_vect object but
you have not defined what that means. Presumably you want it to do the
subscript on the self.e_vect in the Eigen_vect instance. Therefore you
have to define the __getitem__ method in the Eigen_vect class.


class Eigen_vect:
    def __init__(self, e_val, e_vect):
        self.e_val  = e_val
        self.e_vect = e_vect
    def length(self):
        return len(self.e_vect)

    def __getitem__(self, indx):
        return self.e_vect[indx]

I hope I did not make a mistake, I didn't check it because I don't want
to make test input files.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From nobody at nowhere.com  Thu Jul 16 16:17:05 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 21:17:05 +0100
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
	<mailman.3219.1247753940.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.20.15.13.719000@nowhere.com>

On Thu, 16 Jul 2009 09:18:47 -0500, Tim Chase wrote:

> Yes, the dictatorial "a tab always equals 8 spaces"

Saying "always" is incorrect; it is more accurate to say that tab stops
are every 8 columns unless proven otherwise, with the burden of proof
falling on whoever wants to use something different.



From mensanator at aol.com  Thu Jul 16 16:23:38 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 16 Jul 2009 13:23:38 -0700 (PDT)
Subject: list of all possible values
References: <mailman.3054.1247502101.8015.python-list@python.org> 
	<907717ce-a3b1-46a3-80c1-7f2e59dbc501@q35g2000vbi.googlegroups.com> 
	<8AEDA5E3386EA742B8C24C95FF0C7580078FF522@PDC-MAIL3.ubisoft.org> 
	<ef49cad40907160915s69681305g12e9e0837f3699c5@mail.gmail.com> 
	<mailman.3227.1247762965.8015.python-list@python.org>
Message-ID: <c6064b08-6f68-4ce4-8eb9-83ad32eea919@k6g2000yqn.googlegroups.com>

On Jul 16, 11:49 am, "Andreas Tawn" <andreas.t... at ubisoft.com> wrote:
> > > Certainly possible with list comprehensions.
>
> > >>>> a = "abc"
> > >>>> [(x, y) for x in a for y in a]
> > > [('a', 'a'), ('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'b'), ('b',
> 'c'),
> > > ('c', 'a'), ('c', 'b'), ('c', 'c')]
>
> > > But I like bearophile's version better.
>
> > Andreas,
>
> > Thanks, but I think you were missing my point. I should have explained
> better.
>
> > The advantage that bearophile's version is generic with respect to the
> > number of elements in each combination. To go from 2 element pairs
> > (e.g. ('a', 'c')) to 5 element pairs (e.g. ('a', 'c', 'b', 'b', 'e'))
> > requires only a change in a parameter passed to itertools.
>
> > I don't see how you would do that with list comprehensions. You're
> > example works nicely with 2 element pairs, but it seems to me like
> > you'd need to recode it if you wanted to change it to 5 element pairs.
>
> > Am I wrong about that? Can you think of a way to write a function
> > that, using list comprehensions, takes a list of values and the size
> > of each combination, and returns the len(list)**(combination size)
> > possible combinations using those values?
>
> > Thanks again,
> > David
>
> David,
>
> I think my post got caught in the nebulous email eddys and seems to have
> taken 16 hours to arrive on the list. It was meant to be a reply to your
> first post, not your second.
>
> Having said that, I think I missed the point of that post too ;o)
>
> Maybe someone smarter than me can come up with a way to dynamically nest
> the fors in a list comprehension, but I certainly can't do it.

Well, I don't use list comprehension, but you can certainly
make dynamic for loops. Not that this is a replacement for
itertools (I wrote it before itertools had the ability to do
all this).

def ooloop6(a, n, perm=True, repl=True):
    if (not repl) and (n>len(a)): return
    r0 = range(n)
    r1 = r0[1:]
    if perm and repl:                          # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        e = ''.join(["p = [''.join((",v,")) ",f,"]"])
        exec e
        return p
    if (not perm) and repl:                    # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        i = ' and '.join(['(c%s>=c%s)' % (j,j-1) for j in r1])
        e = ''.join(["p = [''.join((",v,")) ",f," if ",i,"]"])
        exec e
        return p
    if perm and (not repl):                    # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        i = ' and '.join([' and '.join(['(c%s!=c%s)' % (j,k) for k in
range(j)]) for j in r1])
        e = ''.join(["p = [''.join((",v,")) ",f," if ",i,"]"])
        exec e
        return p
    if (not perm) and (not repl):              # ok
        v = ','.join(['c%s' % i for i in r0])
        f = ' '.join(['for c%s in a' % i for i in r0])
        i = ' and '.join(['(c%s>c%s)' % (j,j-1) for j in r1])
        e = ''.join(["p = [''.join((",v,")) ",f," if ",i,"]"])
        exec e
        return p

print '0123456789 taken 2 at a time'

p = ooloop6('0123456789',2,True,True)
print
print 'Permutations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',2,True,False)
print
print 'Permutations without Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',2,False,True)
print
print 'Combinations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',2,False,False)
print
print 'Combinations without Replacement: %6d' % (len(p))
print p

print

print '0123456789 taken 3 at a time'

p = ooloop6('0123456789',3,True,True)
print
print 'Permutations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',3,True,False)
print
print 'Permutations without Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',3,False,True)
print
print 'Combinations with    Replacement: %6d' % (len(p))
print p

p = ooloop6('0123456789',3,False,False)
print
print 'Combinations without Replacement: %6d' % (len(p))
print p

0123456789 taken 2 at a time

Permutations with    Replacement:    100
['00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '10',
'11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21',
'22', '23', '24', '25', '26', '27', '28', '29', '30', '31', '32',
'33', '34', '35', '36', '37', '38', '39', '40', '41', '42', '43',
'44', '45', '46', '47', '48', '49', '50', '51', '52', '53', '54',
'55', '56', '57', '58', '59', '60', '61', '62', '63', '64', '65',
'66', '67', '68', '69', '70', '71', '72', '73', '74', '75', '76',
'77', '78', '79', '80', '81', '82', '83', '84', '85', '86', '87',
'88', '89', '90', '91', '92', '93', '94', '95', '96', '97', '98',
'99']

Permutations without Replacement:     90
['01', '02', '03', '04', '05', '06', '07', '08', '09', '10', '12',
'13', '14', '15', '16', '17', '18', '19', '20', '21', '23', '24',
'25', '26', '27', '28', '29', '30', '31', '32', '34', '35', '36',
'37', '38', '39', '40', '41', '42', '43', '45', '46', '47', '48',
'49', '50', '51', '52', '53', '54', '56', '57', '58', '59', '60',
'61', '62', '63', '64', '65', '67', '68', '69', '70', '71', '72',
'73', '74', '75', '76', '78', '79', '80', '81', '82', '83', '84',
'85', '86', '87', '89', '90', '91', '92', '93', '94', '95', '96',
'97', '98']

Combinations with    Replacement:     55
['00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '11',
'12', '13', '14', '15', '16', '17', '18', '19', '22', '23', '24',
'25', '26', '27', '28', '29', '33', '34', '35', '36', '37', '38',
'39', '44', '45', '46', '47', '48', '49', '55', '56', '57', '58',
'59', '66', '67', '68', '69', '77', '78', '79', '88', '89', '99']

Combinations without Replacement:     45
['01', '02', '03', '04', '05', '06', '07', '08', '09', '12', '13',
'14', '15', '16', '17', '18', '19', '23', '24', '25', '26', '27',
'28', '29', '34', '35', '36', '37', '38', '39', '45', '46', '47',
'48', '49', '56', '57', '58', '59', '67', '68', '69', '78', '79',
'89']

0123456789 taken 3 at a time

Permutations with    Replacement:   1000
['000', '001', '002', '003', '004', '005', '006', '007', '008', '009',
'010', '011', '012', '013', '014', '015', '016', '017', '018', '019',
'020', '021', '022', '023', '024', '025', '026', '027', '028', '029',
'030', '031', '032', '033', '034', '035', '036', '037', '038', '039',
'040', '041', '042', '043', '044', '045', '046', '047', '048', '049',
'050', '051', '052', '053', '054', '055', '056', '057', '058', '059',
'060', '061', '062', '063', '064', '065', '066', '067', '068', '069',
'070', '071', '072', '073', '074', '075', '076', '077', '078', '079',
'080', '081', '082', '083', '084', '085', '086', '087', '088', '089',
'090', '091', '092', '093', '094', '095', '096', '097', '098', '099',
'100', '101', '102', '103', '104', '105', '106', '107', '108', '109',
'110', '111', '112', '113', '114', '115', '116', '117', '118', '119',
'120', '121', '122', '123', '124', '125', '126', '127', '128', '129',
'130', '131', '132', '133', '134', '135', '136', '137', '138', '139',
'140', '141', '142', '143', '144', '145', '146', '147', '148', '149',
'150', '151', '152', '153', '154', '155', '156', '157', '158', '159',
'160', '161', '162', '163', '164', '165', '166', '167', '168', '169',
'170', '171', '172', '173', '174', '175', '176', '177', '178', '179',
'180', '181', '182', '183', '184', '185', '186', '187', '188', '189',
'190', '191', '192', '193', '194', '195', '196', '197', '198', '199',
'200', '201', '202', '203', '204', '205', '206', '207', '208', '209',
'210', '211', '212', '213', '214', '215', '216', '217', '218', '219',
'220', '221', '222', '223', '224', '225', '226', '227', '228', '229',
'230', '231', '232', '233', '234', '235', '236', '237', '238', '239',
'240', '241', '242', '243', '244', '245', '246', '247', '248', '249',
'250', '251', '252', '253', '254', '255', '256', '257', '258', '259',
'260', '261', '262', '263', '264', '265', '266', '267', '268', '269',
'270', '271', '272', '273', '274', '275', '276', '277', '278', '279',
'280', '281', '282', '283', '284', '285', '286', '287', '288', '289',
'290', '291', '292', '293', '294', '295', '296', '297', '298', '299',
'300', '301', '302', '303', '304', '305', '306', '307', '308', '309',
'310', '311', '312', '313', '314', '315', '316', '317', '318', '319',
'320', '321', '322', '323', '324', '325', '326', '327', '328', '329',
'330', '331', '332', '333', '334', '335', '336', '337', '338', '339',
'340', '341', '342', '343', '344', '345', '346', '347', '348', '349',
'350', '351', '352', '353', '354', '355', '356', '357', '358', '359',
'360', '361', '362', '363', '364', '365', '366', '367', '368', '369',
'370', '371', '372', '373', '374', '375', '376', '377', '378', '379',
'380', '381', '382', '383', '384', '385', '386', '387', '388', '389',
'390', '391', '392', '393', '394', '395', '396', '397', '398', '399',
'400', '401', '402', '403', '404', '405', '406', '407', '408', '409',
'410', '411', '412', '413', '414', '415', '416', '417', '418', '419',
'420', '421', '422', '423', '424', '425', '426', '427', '428', '429',
'430', '431', '432', '433', '434', '435', '436', '437', '438', '439',
'440', '441', '442', '443', '444', '445', '446', '447', '448', '449',
'450', '451', '452', '453', '454', '455', '456', '457', '458', '459',
'460', '461', '462', '463', '464', '465', '466', '467', '468', '469',
'470', '471', '472', '473', '474', '475', '476', '477', '478', '479',
'480', '481', '482', '483', '484', '485', '486', '487', '488', '489',
'490', '491', '492', '493', '494', '495', '496', '497', '498', '499',
'500', '501', '502', '503', '504', '505', '506', '507', '508', '509',
'510', '511', '512', '513', '514', '515', '516', '517', '518', '519',
'520', '521', '522', '523', '524', '525', '526', '527', '528', '529',
'530', '531', '532', '533', '534', '535', '536', '537', '538', '539',
'540', '541', '542', '543', '544', '545', '546', '547', '548', '549',
'550', '551', '552', '553', '554', '555', '556', '557', '558', '559',
'560', '561', '562', '563', '564', '565', '566', '567', '568', '569',
'570', '571', '572', '573', '574', '575', '576', '577', '578', '579',
'580', '581', '582', '583', '584', '585', '586', '587', '588', '589',
'590', '591', '592', '593', '594', '595', '596', '597', '598', '599',
'600', '601', '602', '603', '604', '605', '606', '607', '608', '609',
'610', '611', '612', '613', '614', '615', '616', '617', '618', '619',
'620', '621', '622', '623', '624', '625', '626', '627', '628', '629',
'630', '631', '632', '633', '634', '635', '636', '637', '638', '639',
'640', '641', '642', '643', '644', '645', '646', '647', '648', '649',
'650', '651', '652', '653', '654', '655', '656', '657', '658', '659',
'660', '661', '662', '663', '664', '665', '666', '667', '668', '669',
'670', '671', '672', '673', '674', '675', '676', '677', '678', '679',
'680', '681', '682', '683', '684', '685', '686', '687', '688', '689',
'690', '691', '692', '693', '694', '695', '696', '697', '698', '699',
'700', '701', '702', '703', '704', '705', '706', '707', '708', '709',
'710', '711', '712', '713', '714', '715', '716', '717', '718', '719',
'720', '721', '722', '723', '724', '725', '726', '727', '728', '729',
'730', '731', '732', '733', '734', '735', '736', '737', '738', '739',
'740', '741', '742', '743', '744', '745', '746', '747', '748', '749',
'750', '751', '752', '753', '754', '755', '756', '757', '758', '759',
'760', '761', '762', '763', '764', '765', '766', '767', '768', '769',
'770', '771', '772', '773', '774', '775', '776', '777', '778', '779',
'780', '781', '782', '783', '784', '785', '786', '787', '788', '789',
'790', '791', '792', '793', '794', '795', '796', '797', '798', '799',
'800', '801', '802', '803', '804', '805', '806', '807', '808', '809',
'810', '811', '812', '813', '814', '815', '816', '817', '818', '819',
'820', '821', '822', '823', '824', '825', '826', '827', '828', '829',
'830', '831', '832', '833', '834', '835', '836', '837', '838', '839',
'840', '841', '842', '843', '844', '845', '846', '847', '848', '849',
'850', '851', '852', '853', '854', '855', '856', '857', '858', '859',
'860', '861', '862', '863', '864', '865', '866', '867', '868', '869',
'870', '871', '872', '873', '874', '875', '876', '877', '878', '879',
'880', '881', '882', '883', '884', '885', '886', '887', '888', '889',
'890', '891', '892', '893', '894', '895', '896', '897', '898', '899',
'900', '901', '902', '903', '904', '905', '906', '907', '908', '909',
'910', '911', '912', '913', '914', '915', '916', '917', '918', '919',
'920', '921', '922', '923', '924', '925', '926', '927', '928', '929',
'930', '931', '932', '933', '934', '935', '936', '937', '938', '939',
'940', '941', '942', '943', '944', '945', '946', '947', '948', '949',
'950', '951', '952', '953', '954', '955', '956', '957', '958', '959',
'960', '961', '962', '963', '964', '965', '966', '967', '968', '969',
'970', '971', '972', '973', '974', '975', '976', '977', '978', '979',
'980', '981', '982', '983', '984', '985', '986', '987', '988', '989',
'990', '991', '992', '993', '994', '995', '996', '997', '998', '999']

Permutations without Replacement:    720
['012', '013', '014', '015', '016', '017', '018', '019', '021', '023',
'024', '025', '026', '027', '028', '029', '031', '032', '034', '035',
'036', '037', '038', '039', '041', '042', '043', '045', '046', '047',
'048', '049', '051', '052', '053', '054', '056', '057', '058', '059',
'061', '062', '063', '064', '065', '067', '068', '069', '071', '072',
'073', '074', '075', '076', '078', '079', '081', '082', '083', '084',
'085', '086', '087', '089', '091', '092', '093', '094', '095', '096',
'097', '098', '102', '103', '104', '105', '106', '107', '108', '109',
'120', '123', '124', '125', '126', '127', '128', '129', '130', '132',
'134', '135', '136', '137', '138', '139', '140', '142', '143', '145',
'146', '147', '148', '149', '150', '152', '153', '154', '156', '157',
'158', '159', '160', '162', '163', '164', '165', '167', '168', '169',
'170', '172', '173', '174', '175', '176', '178', '179', '180', '182',
'183', '184', '185', '186', '187', '189', '190', '192', '193', '194',
'195', '196', '197', '198', '201', '203', '204', '205', '206', '207',
'208', '209', '210', '213', '214', '215', '216', '217', '218', '219',
'230', '231', '234', '235', '236', '237', '238', '239', '240', '241',
'243', '245', '246', '247', '248', '249', '250', '251', '253', '254',
'256', '257', '258', '259', '260', '261', '263', '264', '265', '267',
'268', '269', '270', '271', '273', '274', '275', '276', '278', '279',
'280', '281', '283', '284', '285', '286', '287', '289', '290', '291',
'293', '294', '295', '296', '297', '298', '301', '302', '304', '305',
'306', '307', '308', '309', '310', '312', '314', '315', '316', '317',
'318', '319', '320', '321', '324', '325', '326', '327', '328', '329',
'340', '341', '342', '345', '346', '347', '348', '349', '350', '351',
'352', '354', '356', '357', '358', '359', '360', '361', '362', '364',
'365', '367', '368', '369', '370', '371', '372', '374', '375', '376',
'378', '379', '380', '381', '382', '384', '385', '386', '387', '389',
'390', '391', '392', '394', '395', '396', '397', '398', '401', '402',
'403', '405', '406', '407', '408', '409', '410', '412', '413', '415',
'416', '417', '418', '419', '420', '421', '423', '425', '426', '427',
'428', '429', '430', '431', '432', '435', '436', '437', '438', '439',
'450', '451', '452', '453', '456', '457', '458', '459', '460', '461',
'462', '463', '465', '467', '468', '469', '470', '471', '472', '473',
'475', '476', '478', '479', '480', '481', '482', '483', '485', '486',
'487', '489', '490', '491', '492', '493', '495', '496', '497', '498',
'501', '502', '503', '504', '506', '507', '508', '509', '510', '512',
'513', '514', '516', '517', '518', '519', '520', '521', '523', '524',
'526', '527', '528', '529', '530', '531', '532', '534', '536', '537',
'538', '539', '540', '541', '542', '543', '546', '547', '548', '549',
'560', '561', '562', '563', '564', '567', '568', '569', '570', '571',
'572', '573', '574', '576', '578', '579', '580', '581', '582', '583',
'584', '586', '587', '589', '590', '591', '592', '593', '594', '596',
'597', '598', '601', '602', '603', '604', '605', '607', '608', '609',
'610', '612', '613', '614', '615', '617', '618', '619', '620', '621',
'623', '624', '625', '627', '628', '629', '630', '631', '632', '634',
'635', '637', '638', '639', '640', '641', '642', '643', '645', '647',
'648', '649', '650', '651', '652', '653', '654', '657', '658', '659',
'670', '671', '672', '673', '674', '675', '678', '679', '680', '681',
'682', '683', '684', '685', '687', '689', '690', '691', '692', '693',
'694', '695', '697', '698', '701', '702', '703', '704', '705', '706',
'708', '709', '710', '712', '713', '714', '715', '716', '718', '719',
'720', '721', '723', '724', '725', '726', '728', '729', '730', '731',
'732', '734', '735', '736', '738', '739', '740', '741', '742', '743',
'745', '746', '748', '749', '750', '751', '752', '753', '754', '756',
'758', '759', '760', '761', '762', '763', '764', '765', '768', '769',
'780', '781', '782', '783', '784', '785', '786', '789', '790', '791',
'792', '793', '794', '795', '796', '798', '801', '802', '803', '804',
'805', '806', '807', '809', '810', '812', '813', '814', '815', '816',
'817', '819', '820', '821', '823', '824', '825', '826', '827', '829',
'830', '831', '832', '834', '835', '836', '837', '839', '840', '841',
'842', '843', '845', '846', '847', '849', '850', '851', '852', '853',
'854', '856', '857', '859', '860', '861', '862', '863', '864', '865',
'867', '869', '870', '871', '872', '873', '874', '875', '876', '879',
'890', '891', '892', '893', '894', '895', '896', '897', '901', '902',
'903', '904', '905', '906', '907', '908', '910', '912', '913', '914',
'915', '916', '917', '918', '920', '921', '923', '924', '925', '926',
'927', '928', '930', '931', '932', '934', '935', '936', '937', '938',
'940', '941', '942', '943', '945', '946', '947', '948', '950', '951',
'952', '953', '954', '956', '957', '958', '960', '961', '962', '963',
'964', '965', '967', '968', '970', '971', '972', '973', '974', '975',
'976', '978', '980', '981', '982', '983', '984', '985', '986', '987']

Combinations with    Replacement:    220
['000', '001', '002', '003', '004', '005', '006', '007', '008', '009',
'011', '012', '013', '014', '015', '016', '017', '018', '019', '022',
'023', '024', '025', '026', '027', '028', '029', '033', '034', '035',
'036', '037', '038', '039', '044', '045', '046', '047', '048', '049',
'055', '056', '057', '058', '059', '066', '067', '068', '069', '077',
'078', '079', '088', '089', '099', '111', '112', '113', '114', '115',
'116', '117', '118', '119', '122', '123', '124', '125', '126', '127',
'128', '129', '133', '134', '135', '136', '137', '138', '139', '144',
'145', '146', '147', '148', '149', '155', '156', '157', '158', '159',
'166', '167', '168', '169', '177', '178', '179', '188', '189', '199',
'222', '223', '224', '225', '226', '227', '228', '229', '233', '234',
'235', '236', '237', '238', '239', '244', '245', '246', '247', '248',
'249', '255', '256', '257', '258', '259', '266', '267', '268', '269',
'277', '278', '279', '288', '289', '299', '333', '334', '335', '336',
'337', '338', '339', '344', '345', '346', '347', '348', '349', '355',
'356', '357', '358', '359', '366', '367', '368', '369', '377', '378',
'379', '388', '389', '399', '444', '445', '446', '447', '448', '449',
'455', '456', '457', '458', '459', '466', '467', '468', '469', '477',
'478', '479', '488', '489', '499', '555', '556', '557', '558', '559',
'566', '567', '568', '569', '577', '578', '579', '588', '589', '599',
'666', '667', '668', '669', '677', '678', '679', '688', '689', '699',
'777', '778', '779', '788', '789', '799', '888', '889', '899', '999']

Combinations without Replacement:    120
['012', '013', '014', '015', '016', '017', '018', '019', '023', '024',
'025', '026', '027', '028', '029', '034', '035', '036', '037', '038',
'039', '045', '046', '047', '048', '049', '056', '057', '058', '059',
'067', '068', '069', '078', '079', '089', '123', '124', '125', '126',
'127', '128', '129', '134', '135', '136', '137', '138', '139', '145',
'146', '147', '148', '149', '156', '157', '158', '159', '167', '168',
'169', '178', '179', '189', '234', '235', '236', '237', '238', '239',
'245', '246', '247', '248', '249', '256', '257', '258', '259', '267',
'268', '269', '278', '279', '289', '345', '346', '347', '348', '349',
'356', '357', '358', '359', '367', '368', '369', '378', '379', '389',
'456', '457', '458', '459', '467', '468', '469', '478', '479', '489',
'567', '568', '569', '578', '579', '589', '678', '679', '689', '789']
>>>

>
> Sorry for the confusion.
>
> Cheers,
>
> Drea


From nobody at nowhere.com  Thu Jul 16 16:25:50 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 21:25:50 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<mailman.3209.1247735227.8015.python-list@python.org>
Message-ID: <pan.2009.07.16.20.23.58.953000@nowhere.com>

On Thu, 16 Jul 2009 11:06:54 +0200, Jean-Michel Pichavant wrote:

>>> So if I resume:
>>> - not 'foo' => False
>>> - 'foo' or 'foo' => 'foo'
>>>
>>> I may be missing something, but honestly, Guido must have smoked some 
>>> heavy stuff to write such logic, has he ?
>>
>> Several languages (e.g. Lisp, Bourne shell) behave the same way, i.e. "or"
>> returns the first element which is considered true while "and" returns the
>> last element provided that all preceding elements are considered true.
>>   
>> [snip]
>>   
> 
> Ok then, why "or" does not return True, if the first element is 
> considered True ?

If the first element is true, returning the first element is returning
true.

> Why returning the element itself. Any reason for that ?

Why not? Where is the benefit in collapsing all true values to True? You
can convert values to True/False with bool(), but the conversion cannot be
reversed.

It only makes a difference if you are interested in the representation
rather than the value. Do you normally test for equality with "is" or "=="?



From nobody at nowhere.com  Thu Jul 16 16:29:07 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 21:29:07 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
Message-ID: <pan.2009.07.16.20.27.15.563000@nowhere.com>

On Wed, 15 Jul 2009 18:14:10 +0200, Hrvoje Niksic wrote:

>> If the question was "Why is there no 'or' operator ?", would "because
>> A or B <=> not(not A and not B)" be a proper answer ?
> 
> Note that in Python A or B is in fact not equivalent to not(not A and
> not B).

Ah, but it *is* "equivalent"; it isn't "identical", but that's not the
point.



From nick at craig-wood.com  Thu Jul 16 16:29:59 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 16 Jul 2009 15:29:59 -0500
Subject: This is a mess...
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
	<e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
Message-ID: <slrnh5v2fn.b32.nick@irishsea.home.craig-wood.com>

Nick <nleioatt at gmail.com> wrote:
>  this is the new oop version, its pretty messy currently, and i do
>  understand it is a simple routine, but i'm using it as an exercise to
>  learn oop python...
> 
>  first the (current) traceback:
>   [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
>  Traceback (most recent call last):
>    File "oop_covariance.py", line 24, in <module>
>      cov = set1.covariance(set2, Eigen_vect.dot)
>    File "/home/nleioatts/python/Eigen.py", line 66, in covariance
>      print self.vectors[i][i]
>  AttributeError: Eigen_vect instance has no attribute '__getitem__'

You are trying to use your Eigen_vect class as an array.  In order for
an object to act as an array it needs a __getitem__ method.

>  class Eigen_vect:
>      def __init__(self, e_val, e_vect):
>          self.e_val  = e_val
>          self.e_vect = e_vect
>      def length(self):
>          return len(self.e_vect)
> 
>      def dot(self, other):
>          d = 0.0
>          if other.length() != self.length():
>              raise ValueError, "Eigen Vectors not same Length"
>          for k in range(self.length()):
>             # print "HI NICK", self.e_vect[k], other.e_vect[k]
>              d += float(self.e_vect[k]) * float(other.e_vect[k])
>          return d

Either add a __getitem__ method like this

    def __getitem__(self, n):
        return self.e_vect[n]

Or you might want to subclass list if you are going to do a lot of
list like operations on Eigen_vects, eg

class Eigen_vect(list):
    def __init__(self, e_val, e_vect):
        self.e_val  = e_val
        self[:] = e_vect

    def dot(self, other):
        d = 0.0
        if len(other) != len(self):
            raise ValueError("Eigen Vectors not same Length")
        for a, b in zip(self, other):
            d += float(a) * float(b)
        return d

Notice that now these things are lists, you can use len, zip etc on
them which makes the code much neater.

e = Eigen_vect(3, range(10))
f = Eigen_vect(4, range(1,11))

print e
print f
print e[2]
print e.dot(f)

Which prints

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
2
330.0

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From robertrobert93 at yahoo.com  Thu Jul 16 16:41:39 2009
From: robertrobert93 at yahoo.com (Robert Robert)
Date: Thu, 16 Jul 2009 13:41:39 -0700 (PDT)
Subject: file write IOError Invalid argument
Message-ID: <505868.24184.qm@web59308.mail.re1.yahoo.com>

Hello All,
I am trying to write a binary string to file on a windows network share. I get an IOError. I've read that it is because the file size is too large. I did a type( binaryString) and saw that it was type "str". So I loop through it one by one element and use f.write to write to file, and it worked without any error. However it took a long while to write to file. I was wondering how I could split this binary string into N number of chunks efficiently and write them to file. 
thanks,

rh 




      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/416bbe22/attachment-0001.html>

From tjreedy at udel.edu  Thu Jul 16 16:42:48 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 16:42:48 -0400
Subject: turtle dump
In-Reply-To: <4A5F287B.2000503@xs4all.nl>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>
Message-ID: <h3o3c9$h7o$1@ger.gmane.org>

Michiel Overtoom wrote:
> 
> I got success with the following code (python 2.6.2):
> 
> import turtle
> turtle.reset()
> for i in range(4):
>    turtle.forward(50)
>    turtle.right(90)
> can=turtle.getscreen().getcanvas()
> can.postscript(file="tmp.ps")

Is raw postscript (.ps) the only thing tk can write from canvas?
I would like to be able to import into OpenOffice document (drawing 
object) and it can import encapsulated postscript (.eps) and about 20 
other things but not, apparently, .ps.

Help on method postscript:
postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance

is spectacularly useless. I did not see anything similar in the list of 
about 100 attributes. The image_type of the canvas is 'photo bitmap' but 
I see no method to write that.




From tjreedy at udel.edu  Thu Jul 16 16:55:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 16:55:08 -0400
Subject: This is a mess...
In-Reply-To: <e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
References: <8c7ffaf5-67a6-4866-9c9d-271be8b8d8c6@c1g2000yqi.googlegroups.com>
	<e2d59931-738d-4aa5-b72d-5e48884d406b@r33g2000yqn.googlegroups.com>
Message-ID: <h3o43e$jj1$1@ger.gmane.org>

Nick wrote:
> this is the new oop version, its pretty messy currently, and i do
> understand it is a simple routine, but i'm using it as an exercise to
> learn oop python...

You neglected to specify Python version.
> 
> first the (current) traceback:
>  [:~/python]$  python oop_covariance.py b2ar_all_test b2ar_all_test
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
> <Eigen.Eigen_vect instance at 0x7fa26c404ab8>
> Traceback (most recent call last):
>   File "oop_covariance.py", line 24, in <module>
>     cov = set1.covariance(set2, Eigen_vect.dot)
>   File "/home/nleioatts/python/Eigen.py", line 66, in covariance
>     print self.vectors[i][i]
> AttributeError: Eigen_vect instance has no attribute '__getitem__'

self.vectors[i] is apparently an Eigen_vect instance and you try to 
subscript it, but, as the message said, there is no __getitem__ method.

So add one.


> 
> and a quick explaination:  the file structures aare a 2d list of lists
> of numbers corresponding to eginvectors and a list of numbers
> corresponding to eigenvalues
> 
> #########################33##Here is the main body
> #!/usr/bin/env python
> import sys
> import Eigen
> from Eigen import *
> 
> if len(sys.argv) != 3:
>     print " "
>     print "The corrent usage is 'python covariance.py file1 file2'"
>     print "where the _U.asc and _s.asc will be appended when needed"
>     print " "
>     exit(1)
> file1 =  sys.argv[1]
> file2 =  sys.argv[2]
> set1 = Eigen_set(file1+"_U.asc", file1+"_s.asc")
> set2 = Eigen_set(file2+"_U.asc", file2+"_s.asc")
> cov = set1.covariance(set2, Eigen_vect.dot)
> print cov
> 
> 
> ###############and here are the classes:
> 
> #!/usr/bin/env python
> import sys
> import math
> from math import sqrt
> 
> class Eigen_vect:
>     def __init__(self, e_val, e_vect):
>         self.e_val  = e_val
>         self.e_vect = e_vect
>     def length(self):
>         return len(self.e_vect)

You should really call this __len__ so len(Eigen_vect()) will work.

I presume you need something like
def __getitem__(self, i): return self.e_vect[i]

Before continuing, read the Language Reference / Data Model / Special 
method names to understand how to write classes to integrate into syntax.

Terry Jan Reedy



From pavlovevidence at gmail.com  Thu Jul 16 17:00:43 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 16 Jul 2009 14:00:43 -0700 (PDT)
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
Message-ID: <a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>

On Jul 16, 8:12?am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
wrote:
> Hello everyone,
>
> I am using threading.Condition.wait(timeout) and was surprised to see
> that there is no return value nor an exception when wait() is used w/ a
> timeout. How am I supposed to know if it was notified or if it timed out?

That's a good question.  Condition.wait seems to violate an invariant
if it can return without having acquired the underlying lock.  And if
it does the least it could do is to return a status so you know if you
have to skeddadle.

Workaround is to use the _is_owned() method of Condition to see if you
are the owner of the condition, but this method is undocumented.

cond = Condition()
...
cond.acquire()
while not ok_to_proceed():
    cond.wait()
    if not cond._is_owned():
        # must've timed out
        raise TimeOutException
operate()
cond.release()


Carl Banks


From tjreedy at udel.edu  Thu Jul 16 17:10:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 17:10:15 -0400
Subject: interactive fiction in Python?
In-Reply-To: <853a8wlm25.fsf@agentultra.com>
References: <5c97224b-99d4-469b-90cb-1c04b1e1e9a0@m11g2000yqh.googlegroups.com>
	<853a8wlm25.fsf@agentultra.com>
Message-ID: <h3o4vo$mqb$1@ger.gmane.org>

J Kenneth King wrote:
> George Oliver <georgeoliverGO at gmail.com> writes:
> 
>> hi, I'm just curious who might be working on interactive fiction
>> modules in the style of Inform or TADS for Python. I've seen a few
>> threads on this list [1] (among many that mention IF tangentially),
>> and there are old projects like PUB and PAWS. There are some newer
>> potential projects such as Curveship as well. In any case I'd like to
>> see what's out there.

www.renpy.org

Visual novel engine written in Python, with full access to Python as 
needed. Download includes a tutorial written with renpy. You can look as 
source code in a separate window as you go (at least earlier version I 
used did). Also has 150+ free games/novels to download.

"Ren'Py is a free and cross-platform engine that helps you use words, 
pictures, and sounds to tell stories with the computer."

Terry Jan Reedy



From nobody at nowhere.com  Thu Jul 16 17:12:32 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 16 Jul 2009 22:12:32 +0100
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3203.1247729428.8015.python-list@python.org>
	<pan.2009.07.16.07.51.29@REMOVE.THIS.cybersource.com.au>
	<401967fb-c12e-4f63-8b05-6dffa0688028@a26g2000yqn.googlegroups.com>
	<028e48c2-4a3a-4920-9a67-d9bb95714b4f@c36g2000yqn.googlegroups.com>
Message-ID: <pan.2009.07.16.21.10.39.985000@nowhere.com>

On Thu, 16 Jul 2009 03:59:47 -0700, Mark wrote:

>> > Or maybe not. If OrderedDicts are sequences as well as mappings, then we
>> > should be able to sort them. And that seems a bit much even for me.

>> One thing that I've just noticed is that you can use <, <=, >=, and >
>> with sets:

>> It seems a bit inconsistent that with sets you always get False when
>> using an ordering operator but with an ordered dict you get an
>> exception?
> 
> Ooops---disregard the above---I forgot that these do subset and
> superset comparisions!

Which is an argument for dictionaries (ordered or not) doing likewise,
except that the comparison would be subfunction rather than subset,
i.e. d1<d2 = all(k in d2 and d2[k] == d1[k] for k in d1).



From mkhitrov at gmail.com  Thu Jul 16 17:22:32 2009
From: mkhitrov at gmail.com (Maxim Khitrov)
Date: Thu, 16 Jul 2009 17:22:32 -0400
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>
References: <mailman.3221.1247757153.8015.python-list@python.org> 
	<a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>
Message-ID: <26ddd1750907161422n5b640a48pbbf9325dd05a699d@mail.gmail.com>

On Thu, Jul 16, 2009 at 5:00 PM, Carl Banks<pavlovevidence at gmail.com> wrote:
> On Jul 16, 8:12?am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
> wrote:
>> Hello everyone,
>>
>> I am using threading.Condition.wait(timeout) and was surprised to see
>> that there is no return value nor an exception when wait() is used w/ a
>> timeout. How am I supposed to know if it was notified or if it timed out?
>
> That's a good question. ?Condition.wait seems to violate an invariant
> if it can return without having acquired the underlying lock. ?And if
> it does the least it could do is to return a status so you know if you
> have to skeddadle.
>
> Workaround is to use the _is_owned() method of Condition to see if you
> are the owner of the condition, but this method is undocumented.
>
> cond = Condition()
> ...
> cond.acquire()
> while not ok_to_proceed():
> ? ?cond.wait()
> ? ?if not cond._is_owned():
> ? ? ? ?# must've timed out
> ? ? ? ?raise TimeOutException
> operate()
> cond.release()

You will always be the owner of the condition whether it times out or
your thread is notified. This doesn't solve the problem. As an aside,
the implementation of wait() is rather poor in any case; the sleep
function should not be used for the purpose of waiting for an event.

Depending on what platform you are using, I can offer two solutions.
The simplest one is to subclass Condition and override the wait
method. Just copy the code as it is, but modify the end of the
function to look like this:

                if not gotit:
                    if __debug__:
                        self._note("%s.wait(%s): timed out", self, timeout)
                    try:
                        self.__waiters.remove(waiter)
                    except ValueError:
                        pass
                    return False
                else:
                    if __debug__:
                        self._note("%s.wait(%s): got it", self, timeout)
                    return True

The two return statements will tell you whether you timed out ("if not
gotit" condition), or were notified ("else").

The better way to solve this and the other problem that I mentioned is
to use native OS events. This is what I had to do for a recent
project. I used pywin32 extension to completely rewrite Event,
Condition, and Timer classes to use a true event-based approach. In
the process of the rewrite I also modified some functionality, such as
returning True of False from wait().

Unfortunately, I'm not able to post this code right now, though I can
try and get permission to do so a bit later. If you are writing
software for Windows, then simply take a look at win32event module.
CreateEvent, SetEvent, ResetEvent, WaitForSingleObject are all the
Windows functions that you need to reimplement threading.Event. Using
the new event class you can implement a proper Condition.wait() method
(hint: use new events rather than locks to wait for notification).

If you are on Linux or BSD, I can't help you. I'm sure that there is
some equivalent functionality that you may be able to access using
ctypes. Exactly how to do it, however, is not something that I can
help you with right now.

- Max


From __peter__ at web.de  Thu Jul 16 17:37:06 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 16 Jul 2009 23:37:06 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
Message-ID: <h3o6hr$mmh$02$1@news.t-online.com>

Terry Reedy wrote:

> Michiel Overtoom wrote:
>> 
>> I got success with the following code (python 2.6.2):
>> 
>> import turtle
>> turtle.reset()
>> for i in range(4):
>>    turtle.forward(50)
>>    turtle.right(90)
>> can=turtle.getscreen().getcanvas()
>> can.postscript(file="tmp.ps")
> 
> Is raw postscript (.ps) the only thing tk can write from canvas?
> I would like to be able to import into OpenOffice document (drawing
> object) and it can import encapsulated postscript (.eps) and about 20
> other things but not, apparently, .ps.
> 
> Help on method postscript:
> postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance
> 
> is spectacularly useless.

http://docs.python.org/library/turtle.html#turtle.getcanvas

The module is a bit messy, but the accompanying documentation seems OK to 
me. 

> I did not see anything similar in the list of
> about 100 attributes. The image_type of the canvas is 'photo bitmap' but
> I see no method to write that.

That's probably a bitmap that you can draw on the canvas. The Canvas is 
actually that of Tkinter, and according to

http://www.tcl.tk/man/tcl8.5/TkCmd/canvas.htm#M59

it writes Encapsulated Postscript 3.0. Also:

$ file tmp.ps
tmp.ps: PostScript document text conforming DSC level 3.0, type EPS

Try changing the file extension from .ps to .eps.

Peter



From emile at fenx.com  Thu Jul 16 17:59:22 2009
From: emile at fenx.com (Emile van Sebille)
Date: Thu, 16 Jul 2009 14:59:22 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <pan.2009.07.16.20.27.15.563000@nowhere.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<pan.2009.07.16.20.27.15.563000@nowhere.com>
Message-ID: <h3o7md$cf$1@ger.gmane.org>

On 7/16/2009 1:29 PM Nobody said...
> On Wed, 15 Jul 2009 18:14:10 +0200, Hrvoje Niksic wrote:
> 
>>> If the question was "Why is there no 'or' operator ?", would "because
>>> A or B <=> not(not A and not B)" be a proper answer ?
>> Note that in Python A or B is in fact not equivalent to not(not A and
>> not B).
> 
> Ah, but it *is* "equivalent"; it isn't "identical", but that's not the
> point.
> 

I'm not sure I'd call it equivalent.  A or B returns either unaltered, 
and not(not A and not B) always returns a boolean.  The equivalent would 
be not(not( A or B )).

Emile



From piet at cs.uu.nl  Thu Jul 16 18:03:52 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 00:03:52 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
Message-ID: <m21voguvxz.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Hello everyone,
>GR> I am using threading.Condition.wait(timeout) and was surprised to see that
>GR> there is no return value nor an exception when wait() is used w/ a timeout.
>GR> How am I supposed to know if it was notified or if it timed out?

Normally you wouldn't have to know. The logic of your program should be
such that you wait until a certain condition is satisfied. After each
wait you usually check that condition anyway, like:

while (some_condition_satisfied):
    cond_var.wait()

The only exception could be if there is a 1-1 relation between a single
waiter and a single notifier. I that case you can usually use if instead
of while (but it does depend of the logic of the notifier).

So in case of using a timeout you can check the desired condition after
the wait and decide what to do. If the condition was not satisfied you
probably want to do something special, like error handling, or do
something else first and then retry the wait.

There could be situations where this doesn't work, however. For example
if you wait until a queue is not empty, and the notify is done when
something is inserted in the queue, another thread may sneak in while
you are waiting and snatch the inserted item just before your thread
continues after the wait. In that case you can't distinguish between a
timeout and a snatcher.

So it all depends on what your use case is.

(Java's wait doesn't return anything either.)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From thelists at optusnet.com.au  Thu Jul 16 18:07:30 2009
From: thelists at optusnet.com.au (Leo List)
Date: 16 Jul 2009 22:07:30 GMT
Subject: Python 3 xmlrpc client HTTPS problem
Message-ID: <4a5fa4a2$0$3321$afc38c87@news.optusnet.com.au>

I have just built and installed version 3.1 and all's good, but when I 
try to connect to a server via HTTPS I get the following:

  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1029, in __call__
    return self.__send(self.__name, args)
  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1271, in 
__request
    verbose=self.__verbose
  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1058, in request
    http_conn = self.send_request(host, handler, request_body, verbose)
  File "/usr/local/lib/python3.1/xmlrpc/client.py", line 1183, in 
send_request
    "your version of http.client doesn't support HTTPS")
NotImplementedError: your version of http.client doesn't support HTTPS


I am on Ubuntu and have followed the instructions on how to build a 
release with SSL support:

 ./configure CPPFLAGS=-I/usr/include/openssl LDFLAGS=-L/usr/lib/ssl


Any idea what I'm missing?

Thanks


From piet at cs.uu.nl  Thu Jul 16 18:08:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 00:08:08 +0200
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com>
	<mailman.3236.1247773303.8015.python-list@python.org>
Message-ID: <m2ws68th6f.fsf@cs.uu.nl>

>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:

>a> ok!
>a> I got the indentation errors fixed. Bu I get another error:

>a> Traceback (most recent call last):
>a>   File "./temp.py", line 484, in <module>
>a>     main()
>a>   File "./temp.py", line 476, in main
>a>     line.decode('utf-8').strip()
>a> AttributeError: 'str' object has no attribute 'decode'

>a> I am using Python3.1

In Python 3 you can't decode strings because they are Unicode strings
and it doesn't make sense to decode a Unicode string. You can only
decode encoded things which are byte strings. So you are mixing up byte
strings and Unicode strings.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From pavlovevidence at gmail.com  Thu Jul 16 18:15:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 16 Jul 2009 15:15:52 -0700 (PDT)
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org> 
	<a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com> 
	<mailman.3242.1247779375.8015.python-list@python.org>
Message-ID: <bb4d4dc5-5089-4a0a-a01b-f74efc40702e@i6g2000yqj.googlegroups.com>

On Jul 16, 2:22?pm, Maxim Khitrov <mkhit... at gmail.com> wrote:
> On Thu, Jul 16, 2009 at 5:00 PM, Carl Banks<pavlovevide... at gmail.com> wrote:
> > On Jul 16, 8:12?am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
> > wrote:
> >> Hello everyone,
>
> >> I am using threading.Condition.wait(timeout) and was surprised to see
> >> that there is no return value nor an exception when wait() is used w/ a
> >> timeout. How am I supposed to know if it was notified or if it timed out?
>
> > That's a good question. ?Condition.wait seems to violate an invariant
> > if it can return without having acquired the underlying lock. ?And if
> > it does the least it could do is to return a status so you know if you
> > have to skeddadle.
>
> > Workaround is to use the _is_owned() method of Condition to see if you
> > are the owner of the condition, but this method is undocumented.
>
> > cond = Condition()
> > ...
> > cond.acquire()
> > while not ok_to_proceed():
> > ? ?cond.wait()
> > ? ?if not cond._is_owned():
> > ? ? ? ?# must've timed out
> > ? ? ? ?raise TimeOutException
> > operate()
> > cond.release()
>
> You will always be the owner of the condition whether it times out or
> your thread is notified. This doesn't solve the problem.

You are correct, I misread the code.  So scratch what I said.


Carl Banks


From akhilanger at gmail.com  Thu Jul 16 18:43:37 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 15:43:37 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <m2ws68th6f.fsf@cs.uu.nl>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
Message-ID: <24525761.post@talk.nabble.com>


Then, how should I do it?
I read a byte string from sys.stdin which needs to converted to unicode
string for further processing. I cannot just remove the decode statement and
proceed?

This is it what it looks like:

for line in sys.stdin:
    line = line.decode('utf-8').strip()
    if line == '<page>': #do something here
    elsif #do something here
    
If I remove the decode statement, line == '<page>' never gets true. 

--Akhil


Piet van Oostrum wrote:
> 
>>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:
> 
>>a> ok!
>>a> I got the indentation errors fixed. Bu I get another error:
> 
>>a> Traceback (most recent call last):
>>a>   File "./temp.py", line 484, in <module>
>>a>     main()
>>a>   File "./temp.py", line 476, in main
>>a>     line.decode('utf-8').strip()
>>a> AttributeError: 'str' object has no attribute 'decode'
> 
>>a> I am using Python3.1
> 
> In Python 3 you can't decode strings because they are Unicode strings
> and it doesn't make sense to decode a Unicode string. You can only
> decode encoded things which are byte strings. So you are mixing up byte
> strings and Unicode strings.
> -- 
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24525761.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From tjreedy at udel.edu  Thu Jul 16 19:06:55 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 19:06:55 -0400
Subject: turtle dump
In-Reply-To: <h3o6hr$mmh$02$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com>
Message-ID: <h3obqg$aru$1@ger.gmane.org>

Peter Otten wrote:
> Terry Reedy wrote:

>> Help on method postscript:
>> postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance
>>
>> is spectacularly useless.

This is from interactive help.

> http://docs.python.org/library/turtle.html#turtle.getcanvas

That method, following your lead, is how I got to .postscript.
The doc says

" Return the Canvas of this TurtleScreen. Useful for insiders who know 
what to do with a Tkinter Canvas."

> The module is a bit messy, but the accompanying documentation seems OK to 
> me. 

?? I am not an 'insider' ;-).

>> I did not see anything similar in the list of
>> about 100 attributes. 

Of Canvas, mostly methods. I can understand that no one who could write 
decent doc strings for the 100 methods has actually volunteered to do so.

>The image_type of the canvas is 'photo bitmap' but
>> I see no method to write that.
> 
> That's probably a bitmap that you can draw on the canvas. The Canvas is 
> actually that of Tkinter, and according to
> 
> http://www.tcl.tk/man/tcl8.5/TkCmd/canvas.htm#M59
> 
> it writes Encapsulated Postscript 3.0. Also:
> 
> $ file tmp.ps
> tmp.ps: PostScript document text conforming DSC level 3.0, type EPS
> 
> Try changing the file extension from .ps to .eps.

I will. Thank you.

tjr



From graham.dumpleton at gmail.com  Thu Jul 16 19:25:37 2009
From: graham.dumpleton at gmail.com (Graham Dumpleton)
Date: Thu, 16 Jul 2009 16:25:37 -0700 (PDT)
Subject: does python have a generic object pool like commons-pool in Java
References: <4f9a4244-3bae-4a6d-92a8-cd622ffccad2@m11g2000yqh.googlegroups.com>
	<38a7cf0b-fc70-4dee-a2c9-fcd999686dc8@j32g2000yqh.googlegroups.com> 
	<12811e51-86a9-42b4-be61-b4e02961ab87@q11g2000yqi.googlegroups.com> 
	<4a5ea61b$0$1682$742ec2ed@news.sonic.net>
	<0450b7d2-b9f6-4dc9-adf7-67e94b8f8b9b@v37g2000prg.googlegroups.com>
	<4a5eb46a$0$1673$742ec2ed@news.sonic.net>
Message-ID: <ed921183-e5de-4d1c-b9f3-cb85d880bcf0@x5g2000prf.googlegroups.com>

On Jul 16, 3:05?pm, John Nagle <na... at animats.com> wrote:
> alex23 wrote:
> > On Jul 16, 2:03 pm, John Nagle <na... at animats.com> wrote:
> >> ? ? ?"fcgi" is an option for this sort of thing. ?With "mod_fcgi" installed
> >> in Apache, and "fcgi.py" used to manage the Python side of the problem, you
> >> can have semi-persistent programs started up and shut down for you on the
> >> server side.
>
> > Hey John,
>
> > The environments in which I've been asked to develop webs apps using
> > Python have all utilisedmod_wsgi. Do you have any experience with
> >mod_wsgivs mod_fcgi, and if so, can you comment on any relevant
> > performance / capability / ease-of-use differences?
>
> > Cheers,
> > alex23
>
> ? ? FCGI seems to be somewhat out of favor, perhaps because it isn't
> complicated enough.

I doubt that is the reason. It is out of favour for Python web hosting
at least, because web hosting companies provide really crappy support
for using Python with it and also don't like long lived processes.
Most FASTCGI deployments are configured in a way more appropriate for
PHP because that is what the default settings favour. This works to
the detriment of Python. Even when people setup FASTCGI themselves,
they still don't play with the configuration to optimise it for their
specific Python application. Thus it can still run poorly.

> It's a mature technology and works reasonably well.

But is showing its age. It really needs a refresh. Various of its
design decisions were from when network speeds and bandwidth were much
lower and this complicates the design. Making the protocol format
simpler in some areas would make it easier to implement. The protocol
could also be built on to make process management more flexible,
rather than relying on each implementation to come up with adhoc ways
of managing it.

Part of the problem with FASTCGI, or hosting of dynamic applications
in general, is that web servers primary focus is serving of static
files. Any support for dynamic web applications is more of a bolt on
feature. Thus, web applications using Python will always be at a
disadvantage. PHP manages okay because their model of operation is
closer to the one shot processing of static files. Python requires
persistent to work adequately with modern fat applications.

> It's been a puzzle to me that FCGI was taken out of the
> main Apache code base, because it gives production-level performance
> with CGI-type simplicity.

As far as I know FASTCGI support has in the past never been a part of
the Apache code base. Both mod_fastcgi and mod_fcgid were developed by
independent people and not under the ASF.

In Apache 2.3 development versions (to become 2.4 when released),
there will however be a mod_proxy_fcgi. The ASF has also taken over
management of mod_fcgid and working out how that may be incorporated
into future Apache versions.

> ? ? WSGI has a mode for running Python inside the Apache process,
> which is less secure and doesn't allow multiple Python processes.

Depending on the requirements it is more than adequate and if
configured correctly gives better performance and scalability. Not
everyone runs in a shared hosting environment. The different modes of
mod_wsgi therefore give choice.

> That complicates mod_wsgi considerably,

No it doesn't. It is actual daemon mode that complicates things, not
embedded mode.

> and ties it very closely
> to specific versions of Python and Python modules. ?As a result,
> the WSGI developers are patching at a great rate.

What are you talking about when you say 'As a result, the WSGI
developers are patching at a great rate'? As with some of your other
comments, this is leaning towards being FUD and nothing more. There is
no 'patching at a great rate' going on.

>?I think the thing has too many "l33t features".

It is all about choice and providing flexibility. You may not see a
need for certain features, but it doesn't mean other people don't have
a need for it.

> I'd avoid "embedded mode". ?"Daemon mode" is the way to go if you use WSGI.

I'd agree, but not sure you really understand the reasons for why it
would be preferred.

> I haven't tried WSGI;

Then why comment on it as if you are knowledgeable on it.

> I don't need the grief of a package under heavy development.

More FUD.

Graham


From ben+python at benfinney.id.au  Thu Jul 16 19:56:33 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 09:56:33 +1000
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
Message-ID: <87zlb4gp1q.fsf@benfinney.id.au>

Inky 788 <inky788 at gmail.com> writes:

> On Jul 10, 7:35?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> > Yes. That's a ?should? and not a ?must?, even though PEP 8 says it
> > with a simple imperative::
> >
> > ? ? Use 4 spaces per indentation level.
> 
> That actually sounds pretty weird. "Don't do {foo}. Really, I mean
> *really* don't do {foo}. Oh, also, the interpreter allows you to do
> {foo}. But don't do it! I mean it!".

Not weird at all, especially when you realise that your interpretation
isn't there in the document.

The allowance for both types of indentation is a compromise made for
backward compatibility with code written before this convention was
quite so strong. All *new* code is strongly advised to follow the
convention, while the interpreter will still allow old code that doesn't
follow the convention.

> Very ... perlish, if you ask me.

Hah! Perl doesn't have the ?don't do {foo}? part, so I don't see what
you're seeing.

-- 
 \      ?I like to skate on the other side of the ice.? ?Steven Wright |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From lhughes42 at gmail.com  Thu Jul 16 19:58:36 2009
From: lhughes42 at gmail.com (lh)
Date: Thu, 16 Jul 2009 16:58:36 -0700 (PDT)
Subject: Visualization of Python Class Hierarchy
Message-ID: <e55e6100-48a6-445d-a122-b61db94b8556@f20g2000prn.googlegroups.com>

I would like to automatically generate this for my program. I am
running python in  an eclipse context (pydev).  I am not familiar with
the best current tools.
 Thank you


From wuwei23 at gmail.com  Thu Jul 16 20:37:00 2009
From: wuwei23 at gmail.com (alex23)
Date: Thu, 16 Jul 2009 17:37:00 -0700 (PDT)
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it> 
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it> 
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com> 
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org> 
	<h3o6hr$mmh$02$1@news.t-online.com>
	<mailman.3245.1247785636.8015.python-list@python.org>
Message-ID: <364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>

> >> Help on method postscript:
> >> postscript(self, *args, **kw) method of turtle.ScrolledCanvas instance
> >> is spectacularly useless.
>
> This is from interactive help.

The help in iPython says the same, but also mentions that it's a
dynamically generated function, so it may not be picking up the
docstring that way. turtle.ScrolledCanvas.postscript is similarly
terse, but you can find more info in turtle.Canvas.postscript:

  Print the contents of the canvas to a postscript
  file. Valid options: colormap, colormode, file, fontmap,
  height, pageanchor, pageheight, pagewidth, pagex, pagey,
  rotate, witdh, x, y.

> The doc says
>
> " Return the Canvas of this TurtleScreen. Useful for insiders who know
> what to do with a Tkinter Canvas."
>
> > The module is a bit messy, but the accompanying documentation seems OK to
> > me.
>
> ?? I am not an 'insider' ;-).

I don't think the intent of the turtle module is to be a primer in Tk,
but more of an educational tool. The lack of image export niceties has
a lot to do with the limitations of Tk, but was probably (and I'm
conjecturing here) felt to be outside the scope of what the module
aims to achieve.

> Of Canvas, mostly methods. I can understand that no one who could write
> decent doc strings for the 100 methods has actually volunteered to do so.

I think they all _have_ doc strings, or at least the code they
eventually call does, but I'd have to look into the module itself to
see if they could be brought over dynamically.

You may be interested in the final page of Greg Lingl's PyCon talk,
Seven Ways to use Turtle[1] which states:

  The turtle module is designed in a way so that essentially all of
the turtle
  graphics machinery is based on a class TurtleScreenBase, which
provides the
  interface to the underlying graphics toolkit Tkinter.

  So it?s easy to port turtle.py to different graphics toolkits/
libraries,
  simply by replacing this Tkinter base class with an appropriate
different one.

  I?ve done two ports: Pygame & Jython

If you're after bitmap, I'd suggest contacting Greg and asking about
the Pygame port. His contact info can be found at the original site
for the revised turtle module[2], hopefully it's still up to date.

1: us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-
PyCon2007.pdf
2: http://xturtle.rg16.at/download.html


From tjreedy at udel.edu  Thu Jul 16 20:55:54 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 16 Jul 2009 20:55:54 -0400
Subject: turtle dump
In-Reply-To: <h3obqg$aru$1@ger.gmane.org>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>	<h3o6hr$mmh$02$1@news.t-online.com>
	<h3obqg$aru$1@ger.gmane.org>
Message-ID: <h3oi6r$o6o$1@ger.gmane.org>

Terry Reedy wrote:

>> $ file tmp.ps
>> tmp.ps: PostScript document text conforming DSC level 3.0, type EPS
>>
>> Try changing the file extension from .ps to .eps.
> 
> I will. Thank you.

I tried it. Unfortunately, OOo does not open it correctly. It just 
displays the first three lines of metadate - Title, Creator, Date -- as 
image text. Photoshop does read the image, and does an ok job of 
conversion once anti-aliasing is turned off.

Hmmm. Crazy idea... in
http://us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-PyCon2007.pdf
Gregor Lingl says that turtle.py has been ported to pygame and jython as 
back ends. It should be possible to instead send output to a file 
instead of an on-screen canvas. Run a program to screen. When output 
looks right, return with a different parameter to send to file.

For instance, an OpenDocumentDrawing file (.odd) using odfpy.
This assumes that there are elements corresponding to each turtle 
command. Or at least that the fit is close enough.

Terry Jan Reedy



From ronn.ross at gmail.com  Thu Jul 16 20:57:03 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Thu, 16 Jul 2009 20:57:03 -0400
Subject: TypeError: unbound method
Message-ID: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>

Hello all,

Created a python file that has a class and three methods. When I jump into
interactive mode I import like so:

from <file> import <class>

Now when I try to use a method from the class:

var1 = class.method()

It give me this error:
TypeError: unbound method <methodname> must be called with <classname>
instance as first argument (got int instance instead)

I'm not sure what is going on event after consulting with google
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090716/3a52d02f/attachment-0001.html>

From ben+python at benfinney.id.au  Thu Jul 16 21:01:49 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 11:01:49 +1000
Subject: Override a method but inherit the docstring
Message-ID: <87r5wggm0y.fsf@benfinney.id.au>

Howdy all,

The following is a common idiom::

    class FooGonk(object):
        def frobnicate(self):
            """ Frobnicate this gonk. """
            basic_implementation(self.wobble)

    class BarGonk(FooGonk):
        def frobnicate(self):
            special_implementation(self.warble)

The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
the method, the original docstring is not associated with it.

Ideally there would be a way to specify that the docstring should be
inherited. The best I can come up with is::

    class BarGonk(FooGonk):
        def frobnicate(self):
            special_implementation(self.warble)
        frobnicate.__doc__ = FooGonk.frobnicate.__doc__

but that violates DRY (the association between BarGonk and FooGonk is
being repeated), puts the docstring assignment awkwardly after the end
of the method instead of at the beginning where docstrings normally go,
and reads poorly besides.

What is the most Pythonic, DRY-adherent, and preferably least-ugly
approach to override a method, but have the same docstring on both
methods?

-- 
 \           ?Why, I'd horse-whip you if I had a horse.? ?Groucho Marx |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From clp2 at rebertia.com  Thu Jul 16 21:08:45 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 18:08:45 -0700
Subject: TypeError: unbound method
In-Reply-To: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>
References: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>
Message-ID: <50697b2c0907161808i3bcc55eej333ad83660897313@mail.gmail.com>

On Thu, Jul 16, 2009 at 5:57 PM, Ronn Ross<ronn.ross at gmail.com> wrote:
> Hello all,
>
> Created a python file that has a class and three methods. When I jump into
> interactive mode I import like so:
>
> from <file> import <class>
>
> Now when I try to use a method from the class:
>
> var1 = class.method()
>
> It give me this error:
> TypeError: unbound method <methodname> must be called with <classname>
> instance as first argument (got int instance instead)
>
> I'm not sure what is going on event after consulting with google

You're trying to call an instance method on the class itself, which
doesn't make sense.
You need to first create an instance of the class to invoke the method on.
i.e.:

instance = TheClass(constuctor_arguments_here)
var1 = instance.method()

Cheers,
Chris
-- 
http://blog.rebertia.com


From exarkun at divmod.com  Thu Jul 16 21:13:34 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Thu, 16 Jul 2009 21:13:34 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <20090717011334.2543.775231474.divmod.quotient.2982@henry.divmod.com>

On Fri, 17 Jul 2009 11:01:49 +1000, Ben Finney <ben+python at benfinney.id.au> wrote:
>Howdy all,
>
>The following is a common idiom::
>
>    class FooGonk(object):
>        def frobnicate(self):
>            """ Frobnicate this gonk. """
>            basic_implementation(self.wobble)
>
>    class BarGonk(FooGonk):
>        def frobnicate(self):
>            special_implementation(self.warble)
>
>The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>the method, the original docstring is not associated with it.
>
>Ideally there would be a way to specify that the docstring should be
>inherited. The best I can come up with is::
>
>    class BarGonk(FooGonk):
>        def frobnicate(self):
>            special_implementation(self.warble)
>        frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>
>but that violates DRY (the association between BarGonk and FooGonk is
>being repeated), puts the docstring assignment awkwardly after the end
>of the method instead of at the beginning where docstrings normally go,
>and reads poorly besides.
>
>What is the most Pythonic, DRY-adherent, and preferably least-ugly
>approach to override a method, but have the same docstring on both
>methods?
>

How about this?

    class BarGonk(FooGonk):
        @inherit_docstring
        def frobnicate(self):
            special_implementation(self.warble)

The implementation of "inherit_docstring" is left as an exercise for the
reader (it's not utterly trivial, I admit, as "FooGonk" will not readily
be at hand, but it is still possible).

By the way, I don't think this is a particularly good idea.  Presumably
there is a reason your implementation is special.  It would probably be
better if this were reflected in the docstring somehow.  Perhaps this
idea is a better one:

    class BarGonk(FooGonk):
        @append_to_docstring
        def frobnicate(self):
            """
            This implementation takes the warble into consideration.
            """
            special_implementation(self.warble)

With the result of BarGonk.frobnicate.__doc__ being set to:


     Frobnicate this gonk.

     This implementation takes the warble into consideration.

Jean-Paul


From nobody at nowhere.com  Thu Jul 16 21:16:53 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 17 Jul 2009 02:16:53 +0100
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net>
	<pan.2009.07.16.20.27.15.563000@nowhere.com>
	<mailman.3243.1247781407.8015.python-list@python.org>
Message-ID: <pan.2009.07.17.01.15.01.688000@nowhere.com>

On Thu, 16 Jul 2009 14:59:22 -0700, Emile van Sebille wrote:

>>>> If the question was "Why is there no 'or' operator ?", would "because
>>>> A or B <=> not(not A and not B)" be a proper answer ?
>>> Note that in Python A or B is in fact not equivalent to not(not A and
>>> not B).
>> 
>> Ah, but it *is* "equivalent"; it isn't "identical", but that's not the
>> point.
> 
> I'm not sure I'd call it equivalent.

That depends upon what definition of "equivalent" you are using. Apart
from all manner of vague, informal definitions, there is a formal
definition:

A relation "=" is an equivalence relation if the following hold for all
x, y, and z:

	x = x
	x = y => y = x
	x = y and y = z => x = z

An equivalence relation partitions its domain into equivalence classes,
such that an element is "=" (equivalent) to every element in the same
class, and not "=" to every element in every other class.

This is a lesser notion of equality to "identity", which also requires
that x = y => f(x) = f(y) for all f.

Python's notion of boolean values treats x and y as equivalent if
bool(x) == bool(y).

On this basis, the result of "A or B" is *equivalent* to the result of
"not(not A and not B)". If you use either result as a boolean value (e.g.
the test of an "if" or "while" statement, as an operand to "and" or "or",
etc), the effect is the same. The results aren't *identical*, as there
exist ways to distinguish the two.

As for the utility of this behaviour, returning an actual value rather
than True/False allows the operators to be used as "gates". The term
"gate" in digital logic follows from the axioms: 

	0 and x = 0
	1 and x = x

	0 or x = x
	1 or x = 1

[0 = False, 1 = True]

If you consider the left operand as the "control" and the right operand as
the "data", the control determines whether or not the data can pass
through the gate to the output (i.e. whether the gate is open or closed).

In Python:

and:
	False and 7	=> False
	False and 0	=> False
	True and 7	=> 7
	True and 0	=> 0

or:
	False or 7	=> 7
	False or 0	=> 0
	True or 7	=> True
	True or 0	=> True




From max at alcyone.com  Thu Jul 16 21:18:56 2009
From: max at alcyone.com (Erik Max Francis)
Date: Thu, 16 Jul 2009 18:18:56 -0700
Subject: Einstein summation notation (was: question of style)
In-Reply-To: <kmr2uu.d1t@spenarnc.xs4all.nl>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
Message-ID: <Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>

Albert van der Horst wrote:
> Einstein introduced the summation convention for indices that
> are used twice. Leaving out summation signs is absolutely hideous,
> but it has saved generations of physicists of loosing track (and
> their minds.)

There is a joke among mathematicians that if Einstein hadn't been 
remembered for a couple of other fairly contributions things in physics 
:-), he would have been remembered in mathematics for that convention, 
since it has saved everyone -- mathematicians included -- a lot of time 
and anguish.  When using tensor calculus, there's even very easy ways to 
verify you have a valid tensor equation using it.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   If the sky should fall, hold up your hands.
    -- (a Spanish proverb)


From mkhitrov at gmail.com  Thu Jul 16 21:21:16 2009
From: mkhitrov at gmail.com (Maxim Khitrov)
Date: Thu, 16 Jul 2009 21:21:16 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <20090717011334.2543.775231474.divmod.quotient.2982@henry.divmod.com>
References: <87r5wggm0y.fsf@benfinney.id.au>
	<20090717011334.2543.775231474.divmod.quotient.2982@henry.divmod.com>
Message-ID: <26ddd1750907161821r1a5feeebr1c7c63e0130bf6e7@mail.gmail.com>

On Thu, Jul 16, 2009 at 9:13 PM, Jean-Paul Calderone<exarkun at divmod.com> wrote:
> On Fri, 17 Jul 2009 11:01:49 +1000, Ben Finney <ben+python at benfinney.id.au>
> wrote:
>>
>> Howdy all,
>>
>> The following is a common idiom::
>>
>> ? class FooGonk(object):
>> ? ? ? def frobnicate(self):
>> ? ? ? ? ? """ Frobnicate this gonk. """
>> ? ? ? ? ? basic_implementation(self.wobble)
>>
>> ? class BarGonk(FooGonk):
>> ? ? ? def frobnicate(self):
>> ? ? ? ? ? special_implementation(self.warble)
>>
>> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>> the method, the original docstring is not associated with it.
>>
>> Ideally there would be a way to specify that the docstring should be
>> inherited. The best I can come up with is::
>>
>> ? class BarGonk(FooGonk):
>> ? ? ? def frobnicate(self):
>> ? ? ? ? ? special_implementation(self.warble)
>> ? ? ? frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>>
>> but that violates DRY (the association between BarGonk and FooGonk is
>> being repeated), puts the docstring assignment awkwardly after the end
>> of the method instead of at the beginning where docstrings normally go,
>> and reads poorly besides.
>>
>> What is the most Pythonic, DRY-adherent, and preferably least-ugly
>> approach to override a method, but have the same docstring on both
>> methods?
>>
>
> How about this?
>
> ? class BarGonk(FooGonk):
> ? ? ? @inherit_docstring
> ? ? ? def frobnicate(self):
> ? ? ? ? ? special_implementation(self.warble)
>
> The implementation of "inherit_docstring" is left as an exercise for the
> reader (it's not utterly trivial, I admit, as "FooGonk" will not readily
> be at hand, but it is still possible).
>
> By the way, I don't think this is a particularly good idea. ?Presumably
> there is a reason your implementation is special. ?It would probably be
> better if this were reflected in the docstring somehow. ?Perhaps this
> idea is a better one:
>
> ? class BarGonk(FooGonk):
> ? ? ? @append_to_docstring
> ? ? ? def frobnicate(self):
> ? ? ? ? ? """
> ? ? ? ? ? This implementation takes the warble into consideration.
> ? ? ? ? ? """
> ? ? ? ? ? special_implementation(self.warble)
>
> With the result of BarGonk.frobnicate.__doc__ being set to:
>
>
> ? ?Frobnicate this gonk.
>
> ? ?This implementation takes the warble into consideration.

Another way is to use a metaclass. Have its __new__ method loop
through all attributes and compare those with what is already defined
in bases. If you find a match, copy the __doc__ attribute. The
advantage here is that it will work for all methods without any
additional code, not counting the "__metaclass__ = ..." line. If you
define a metaclass for the base, then no modifications are required
for any subclasses. I do agree, however, that the best thing to do is
to write a very short explanation for what the override is for.

- Max


From nobody at nowhere.com  Thu Jul 16 21:23:41 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 17 Jul 2009 02:23:41 +0100
Subject: UnicodeEncodeError: 'ascii' codec can't encode character	u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<mailman.3244.1247784220.8015.python-list@python.org>
Message-ID: <pan.2009.07.17.01.21.48.641000@nowhere.com>

On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:

>> In Python 3 you can't decode strings because they are Unicode strings
>> and it doesn't make sense to decode a Unicode string. You can only
>> decode encoded things which are byte strings. So you are mixing up byte
>> strings and Unicode strings.
>
> Then, how should I do it?
> I read a byte string from sys.stdin which needs to converted to unicode
> string for further processing.

In 3.x, sys.stdin (stdout, stderr) are text streams, which means that they
read and write Unicode strings, not byte strings.

> I cannot just remove the decode statement and
> proceed?
> 
> This is it what it looks like:
> 
> for line in sys.stdin:
>     line = line.decode('utf-8').strip()
>     if line == '<page>': #do something here
>     elsif #do something here
>     
> If I remove the decode statement, line == '<page>' never gets true. 

Did you inadvertently remove the strip() as well?



From rhodri at wildebst.demon.co.uk  Thu Jul 16 21:31:43 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 17 Jul 2009 02:31:43 +0100
Subject: Override a method but inherit the docstring
In-Reply-To: <87r5wggm0y.fsf@benfinney.id.au>
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <op.uw6ui5w8a8ncjz@gnudebst>

On Fri, 17 Jul 2009 02:01:49 +0100, Ben Finney  
<ben+python at benfinney.id.au> wrote:

> Howdy all,
>
> The following is a common idiom::
>
>     class FooGonk(object):
>         def frobnicate(self):
>             """ Frobnicate this gonk. """
>             basic_implementation(self.wobble)
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
>
> Ideally there would be a way to specify that the docstring should be
> inherited. The best I can come up with is::
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>         frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>
> but that violates DRY (the association between BarGonk and FooGonk is
> being repeated),

Not really.  Consider the case of BarGonk being a subclass of FooGonk
and BazGonk; which docstring would you wish to inherit?

> puts the docstring assignment awkwardly after the end
> of the method instead of at the beginning where docstrings normally go,
> and reads poorly besides.

Sounds like a job for a decorator!

(This is probably unbelievably ugly and unwise, since I don't use
decorators at all often.)

def copydoc(cls):
     def _fn(fn):
         if fn.__name__ in cls.__dict__:
             fn.__doc__ = cls.__dict__[fn.__name__].__doc__
         return fn
     return _fn

class BarGonk(FooGonk):
     @copydoc(FooGonk)
     def frobnicate(self):
         special_implementation(self.warble)

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From ptmcg at austin.rr.com  Thu Jul 16 21:35:05 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Thu, 16 Jul 2009 18:35:05 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>

On Jul 16, 8:01?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Howdy all,
>
> The following is a common idiom::
>
> ? ? class FooGonk(object):
> ? ? ? ? def frobnicate(self):
> ? ? ? ? ? ? """ Frobnicate this gonk. """
> ? ? ? ? ? ? basic_implementation(self.wobble)
>
> ? ? class BarGonk(FooGonk):
> ? ? ? ? def frobnicate(self):
> ? ? ? ? ? ? special_implementation(self.warble)
>
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
>
> What is the most Pythonic, DRY-adherent, and preferably least-ugly
> approach to override a method, but have the same docstring on both
> methods?
>

Two ideas come to mind, the decorator way and the metaclass way.  I am
not a guru at either, but these two examples work:

# the decorator way
def inherit_docstring_from(cls):
    def docstring_inheriting_decorator(fn):
        fn.__doc__ = getattr(cls,fn.__name__).__doc__
        return fn
    return docstring_inheriting_decorator


class FooGonk(object):
    def frobnicate(self):
        """ Frobnicate this gonk. """
        basic_implementation(self.wobble)


class BarGonk(FooGonk):
    @inherit_docstring_from(FooGonk)
    def frobnicate(self):
        special_implementation(self.warble)

bg = BarGonk()
help(bg.frobnicate)

Prints:
Help on method frobnicate in module __main__:

frobnicate(self) method of __main__.BarGonk instance
    Frobnicate this gonk.


Using a decorator in this manner requires repeating the super class
name.  Perhaps there is a way to get the bases of BarGonk, but I don't
think so, because at the time that the decorator is called, BarGonk is
not yet fully defined.



# The metaclass way

from types import FunctionType

class DocStringInheritor(type):
    def __new__(meta, classname, bases, classDict):
        newClassDict = {}
        for attributeName, attribute in classDict.items():
            if type(attribute) == FunctionType:
                # look through bases for matching function by name
                for baseclass in bases:
                    if hasattr(baseclass, attributeName):
                        basefn = getattr(baseclass,attributeName)
                        if basefn.__doc__:
                            attribute.__doc__ = basefn.__doc__
                            break

            newClassDict[attributeName] = attribute

        return type.__new__(meta, classname, bases, newClassDict)

class FooGonk2(object):
    def frobnicate(self):
        """ Frobnicate this gonk. """
        basic_implementation(self.wobble)


class BarGonk2(FooGonk2):
    __metaclass__ = DocStringInheritor
    def frobnicate(self):
        special_implementation(self.warble)

bg = BarGonk2()
help(bg.frobnicate)

Prints:

Help on method frobnicate in module __main__:

frobnicate(self) method of __main__.BarGonk2 instance
    Frobnicate this gonk.


This metaclass will walk the list of bases until the desired
superclass method is found AND if that method has a docstring and only
THEN does it attach the superdocstring to the derived class method.

Please use carefully, I just did the metaclass thing by following
Michael Foord's Metaclass tutorial (http://www.voidspace.org.uk/python/
articles/metaclasses.shtml), I may have missed a step or two.

-- Paul


From vinay_sajip at yahoo.co.uk  Thu Jul 16 21:56:51 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Thu, 16 Jul 2009 18:56:51 -0700 (PDT)
Subject: ANN: gnupg v0.2.0 released
Message-ID: <mailman.3256.1247799947.8015.python-announce-list@python.org>

A new version of the Python module which wraps GnuPG has been
released.

What Changed?
=============
The module was refactored slightly to support Python 3.0.

The current version now passes all tests on Windows (Python 2.4, 2.5)
and Ubuntu (Python 2.4, 2.5, 2.6 and 3.0).

What Does It Do?
================
The gnupg module allows Python programs to make use of the
functionality provided by the Gnu Privacy Guard (abbreviated GPG or
GnuPG). Using this module, Python programs can encrypt and decrypt
data, digitally sign documents and verify digital signatures, manage
(generate, list and delete) encryption keys, using proven Public Key
Infrastructure (PKI) encryption technology based on OpenPGP.

This module is expected to be used with Python versions >= 2.4, as it
makes use of the subprocess module which appeared in that version of
Python. This module is a newer version derived from earlier work by
Andrew Kuchling, Richard Jones and Steve Traugott.

A test suite using unittest is included with the source distribution.

Simple usage:

>>> import gnupg
>>> gpg = gnupg.GPG(gnupghome='/path/to/keyring/directory')
>>> gpg.list_keys()
[{
  ...
  'fingerprint': 'F819EE7705497D73E3CCEE65197D5DAC68F1AAB2',
  'keyid': '197D5DAC68F1AAB2',
  'length': '1024',
  'type': 'pub',
  'uids': ['', 'Gary Gross (A test user) <gary.gross at gamma.com>']},
 {
  ...
  'fingerprint': '37F24DD4B918CC264D4F31D60C5FEFA7A921FC4A',
  'keyid': '0C5FEFA7A921FC4A',
  'length': '1024',
  ...
  'uids': ['', 'Danny Davis (A test user) <danny.davis at delta.com>']}]
>>> encrypted = gpg.encrypt("Hello, world!", ['0C5FEFA7A921FC4A'])
>>> str(encrypted)
'-----BEGIN PGP MESSAGE-----\nVersion: GnuPG v1.4.9 (GNU/Linux)\n
\nhQIOA/6NHMDTXUwcEAf
...
-----END PGP MESSAGE-----\n'
>>> decrypted = gpg.decrypt(str(encrypted), passphrase='secret')
>>> str(decrypted)
'Hello, world!'
>>> signed = gpg.sign("Goodbye, world!", passphrase='secret')
>>> verified = verified = gpg.verify(str(signed))
>>> print "Verified" if verified else "Not verified"
'Verified'

For more information, visit http://code.google.com/p/python-gnupg/ -
as always, your feedback is most welcome (especially bug reports,
patches and suggestions for improvement). Enjoy!

Cheers

Vinay Sajip
Red Dove Consultants Ltd.


From tismer at stackless.com  Thu Jul 16 22:26:02 2009
From: tismer at stackless.com (Christian Tismer)
Date: Fri, 17 Jul 2009 04:26:02 +0200
Subject: ANN: psyco V2
Message-ID: <4A5FE13A.3080708@stackless.com>

Announcing Psyco V2 source release
----------------------------------

This is the long awaited announcement of Psyco V2.

Psyco V2 is a continuation of the well-known psyco project,
which was called finished and was dis-continued by its author
Armin Rigo in 2005, in favor of the PyPy project.

This is a new project, using Psyco's code base with permission
of Armin. Questions aqnd complaints should go to me
(tismer at stackless.com) or the mailing list
(psyco-devel at lists.sourceforge.net);
Armin is explicitly not in charge of (t)his project any longer!

As one of the founders and an active member of the PyPy
project, I was very happy to be invited to work on Psyco
V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
approach "an extension module that just makes Python faster".

Psyco is a just-in-time compiler that accelerates arbitrary
Python code by specialization. We believe that Psyco's approach
can be carried out much further than it was tried so far, when
it's first version was abandoned.

This first V2 release is source-only. There is no web-site, yet,
and there are no binaries for download. These will be available
in a few days on http://www.psyco.org .

For the time being, please stick with subversion access,
building the extension module from source code. The repository
is here:

     http://codespeak.net/svn/psyco/v2/dist

Check-out the repository, and run the setup.py script,
given that you have access to a C compiler.

Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
and Mac OS X. Psyco is not supporting 64 bit, yet. But it
is well being considered.

The current improvements are, shortly:

   - Support for Python 2.4, 2.5 and 2.6
   - a lot of new builtins
   - generators, fast and fully supported.

More information is coming soon on http://www.psyco.org .

This is the beginning of a series of new Psyco versions.
Many more improvements are prepared and about to be published,
soon, starting with the current version 2.0.0 .

Stay tuned, this is just the beginning of psyco's re-birth!

For questions about Psyco V2, please join the mailing list

     psyco-devel at lists.sourceforge.net

or contact me on IRC:

     #psyco on irc.freenode.net .

Psyco V2 is fundamentally supported by FATTOC, LLC.
See http://www.fattoc.com .

Without their continuous support, this work would not have
been possible at all. I wish to express my deepest thanks
to FATTOC, for allowing me to continue on Psyco with all the
energy that this ambitious project needs, and will need.

Further special thanks are going to
Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
Raymond Hettinger, Fabrizio Milo, Michael Foord,
Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
for all the support and discussions.

Looking forward to a great future of Psyco!

July 17, 2009
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From tismer at stackless.com  Thu Jul 16 22:48:18 2009
From: tismer at stackless.com (Christian Tismer)
Date: Fri, 17 Jul 2009 04:48:18 +0200
Subject: ANN: psyco V2
Message-ID: <4A5FE672.3000401@stackless.com>

Announcing Psyco V2 source release
----------------------------------

This is the long awaited announcement of Psyco V2.

Psyco V2 is a continuation of the well-known psyco project,
which was called finished and was dis-continued by its author
Armin Rigo in 2005, in favor of the PyPy project.

This is a new project, using Psyco's code base with permission
of Armin. Questions and complaints should go to me
(tismer at stackless.com) or the mailing list
(psyco-devel at lists.sourceforge.net);
Armin is explicitly not in charge of (t)his project any longer!

As one of the founders and an active member of the PyPy
project, I was very happy to be invited to work on Psyco
V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
approach "an extension module that just makes Python faster".

Psyco is a just-in-time compiler that accelerates arbitrary
Python code by specialization. We believe that Psyco's approach
can be carried out much further than it was tried so far, when
it's first version was abandoned.

This first V2 release is source-only. There is no web-site, yet,
and there are no binaries for download. These will be available
in a few days on http://www.psyco.org .

For the time being, please stick with subversion access,
building the extension module from source code. The repository
is here:

     http://codespeak.net/svn/psyco/v2/dist

Check-out the repository, and run the setup.py script,
given that you have access to a C compiler.

Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
and Mac OS X. Psyco is not supporting 64 bit, yet. But it
is well being considered.

The current improvements are, shortly:

   - Support for Python 2.4, 2.5 and 2.6
   - a lot of new builtins
   - generators, fast and fully supported.

More information is coming soon on http://www.psyco.org .

This is the beginning of a series of new Psyco versions.
Many more improvements are prepared and about to be published,
soon, starting with the current version 2.0.0 .

Stay tuned, this is just the beginning of psyco's re-birth!

For questions about Psyco V2, please join the mailing list

     psyco-devel at lists.sourceforge.net

or contact me on IRC:

     #psyco on irc.freenode.net .

Psyco V2 is fundamentally supported by FATTOC, LLC.
See http://www.fattoc.com .

Without their continuous support, this work would not have
been possible at all. I wish to express my deepest thanks
to FATTOC, for allowing me to continue on Psyco with all the
energy that this ambitious project needs, and will need.

Further special thanks are going to
Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
Raymond Hettinger, Fabrizio Milo, Michael Foord,
Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
for all the support and discussions.

Looking forward to a great future of Psyco!

July 17, 2009
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From ben+python at benfinney.id.au  Thu Jul 16 22:58:48 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 12:58:48 +1000
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
Message-ID: <87ljmogglz.fsf@benfinney.id.au>

Paul McGuire <ptmcg at austin.rr.com> writes:

> Two ideas come to mind, the decorator way and the metaclass way. I am
> not a guru at either, but these two examples work:

I think the decorator idea is most attractive to me, since it can be
applied per method.

> # the decorator way
> def inherit_docstring_from(cls):
>     def docstring_inheriting_decorator(fn):
>         fn.__doc__ = getattr(cls,fn.__name__).__doc__
>         return fn
>     return docstring_inheriting_decorator

That works, thank you.

> Using a decorator in this manner requires repeating the super class
> name.  Perhaps there is a way to get the bases of BarGonk, but I don't
> think so, because at the time that the decorator is called, BarGonk is
> not yet fully defined.

Yes, I tried a few different ways, but within the decorator it seems the
function object is quite unaware of what class it is destined for.

-- 
 \     ?We are human only to the extent that our ideas remain humane.? |
  `\                          ?_Breakfast of Champions_, Kurt Vonnegut |
_o__)                                                                  |
Ben Finney


From akhilanger at gmail.com  Thu Jul 16 23:26:39 2009
From: akhilanger at gmail.com (akhil1988)
Date: Thu, 16 Jul 2009 20:26:39 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <pan.2009.07.17.01.21.48.641000@nowhere.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
Message-ID: <24528030.post@talk.nabble.com>


Well, you were write: unintentionally I removed strip(). But the problem does
not ends here:

I get this error now:

 File "./temp.py", line 488, in <module>
    main()
  File "./temp.py", line 475, in main
    for line in sys.stdin:
  File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
data

for this line:
?


--Akhil

Nobody-38 wrote:
> 
> On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:
> 
>>> In Python 3 you can't decode strings because they are Unicode strings
>>> and it doesn't make sense to decode a Unicode string. You can only
>>> decode encoded things which are byte strings. So you are mixing up byte
>>> strings and Unicode strings.
>>
>> Then, how should I do it?
>> I read a byte string from sys.stdin which needs to converted to unicode
>> string for further processing.
> 
> In 3.x, sys.stdin (stdout, stderr) are text streams, which means that they
> read and write Unicode strings, not byte strings.
> 
>> I cannot just remove the decode statement and
>> proceed?
>> 
>> This is it what it looks like:
>> 
>> for line in sys.stdin:
>>     line = line.decode('utf-8').strip()
>>     if line == '<page>': #do something here
>>     elsif #do something here
>>     
>> If I remove the decode statement, line == '<page>' never gets true. 
> 
> Did you inadvertently remove the strip() as well?
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24528030.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From aahz at pythoncraft.com  Thu Jul 16 23:39:39 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 20:39:39 -0700
Subject: ImportError: No module named _functools
References: <45228cf4-0b37-4c52-bf6f-d7bd124b0f82@l32g2000vbp.googlegroups.com>
	<h3nckg$db3$1@panix3.panix.com>
	<bfd28485-adaf-43ca-963d-3576c1c2cd4e@l2g2000vba.googlegroups.com>
Message-ID: <h3orpr$93l$1@panix3.panix.com>

In article <bfd28485-adaf-43ca-963d-3576c1c2cd4e at l2g2000vba.googlegroups.com>,
Tony  Lay  <tonylay at gmail.com> wrote:
>On Jul 16, 10:14=A0am, a... at pythoncraft.com (Aahz) wrote:
>> In article <45228cf4-0b37-4c52-bf6f-d7bd124b0... at l32g2000vbp.googlegroups=
>.com>,
>> Tony =A0Lay =A0<tony... at gmail.com> wrote:
>>>
>>>Traceback (most recent call last):
>>> =A0File "/usr/local/bin/meld", line 35, in <module>
>>> =A0 =A0import gettext
>>> =A0File "/usr/local/lib/python2.6/gettext.py", line 49, in <module>
>>> =A0 =A0import locale, copy, os, re, struct, sys
>>> =A0File "/usr/local/lib/python2.6/locale.py", line 15, in <module>
>>> =A0 =A0import functools
>>> =A0File "/usr/local/lib/python2.6/functools.py", line 10, in <module>
>>> =A0 =A0from _functools import partial, reduce
>>>ImportError: No module named _functools
>>
>> Where is _functools.so?
>
>/usr/local/lib/python2.6/lib-dynload/
>
>It's in the path...
>export PYTHONHOME=3D/usr/local/lib/python2.6
>export PYTHONPATH=3D/usr/local/lib/python2.6:/usr/local/lib/python2.6/
>site-packages:/usr/local/lib/python2.6/lib-dynload:/usr/local/etc/

What's in sys.path?  You might also get somewhere with "python -vv".
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From aurora00 at gmail.com  Thu Jul 16 23:55:11 2009
From: aurora00 at gmail.com (aurora00 at gmail.com)
Date: Thu, 16 Jul 2009 20:55:11 -0700 (PDT)
Subject: ctype performance benchmark
Message-ID: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>

I have done some performance benchmarking for Python's ctypes library.
I think you may find it interesting. I am planning to use ctypes as an
alternative to writing C extension module for performance enhancement.
Therefore my use case is slight different from the typical use case
for accessing existing third party C libraries. In this case I am both
the user and the implementer of the C library.

In order to determine what is the right granularity for context
switching between Python and C, I have done some benchmarking. I
mainly want to measure the function call overhead. So the test
functions are trivial function like returning the first character of a
string. I compare a pure Python function versus C module function
versus ctypes function. The tests are ran under Python 2.6 on Windows
XP with Intel 2.33Ghz Core Duo.

First of all I want to compare the function to get the first character
of a string. The most basic case is to reference it as the 0th element
of a sequence without calling any function. The produce the fastest
result at 0.0659 usec per loop.

  $ timeit "'abc'[0]"

  10000000 loops, best of 3: 0.0659 usec per loop

As soon as I build a function around it, the cost goes up
substantially. Both pure Python and C extension method shows similar
performance at around 0.5 usec. ctypes function takes about 2.5 times
as long at 1.37 usec.

  $ timeit -s "f=lambda s: s[0]"  "f('abc')"

  1000000 loops, best of 3: 0.506 usec per loop

  $ timeit -s "import mylib" "mylib.py_first('abc')"

  1000000 loops, best of 3: 0.545 usec per loop

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd')"
              "dll.first('abc')"

  1000000 loops, best of 3: 1.37 usec per loop

I repeated the test with a long string (1MB). There are not much
difference in performance. So I can be quite confident that the
parameter is passed by reference (of the internal buffer).

  $ timeit -s "f=lambda s: s[0]; lstr='abcde'*200000"
              "f(lstr)"

  1000000 loops, best of 3: 0.465 usec per loop

  $ timeit -s "import mylib; lstr='abcde'*200000"
              "mylib.py_first(lstr)"

  1000000 loops, best of 3: 0.539 usec per loop

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd')"
           -s "lstr='abcde'*200000"
              "dll.first(lstr)"

  1000000 loops, best of 3: 1.4 usec per loop

Next I have make some attempts to speed up ctypes performance. A
measurable improvement can be attained by eliminating the attribute
look up for the function. Curiously this shows no improvement in the
similar case for C extension.

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd');
           -s "f=dll.first"
              "f('abcde')"

  1000000 loops, best of 3: 1.18 usec per loop

Secondary I have tried to specify the ctypes function prototype. This
actually decrease the performance significantly.

  $ timeit -s "import ctypes; dll = ctypes.CDLL('mylib.pyd')"
           -s "f=dll.first"
           -s "f.argtypes=[ctypes.c_char_p]"
           -s "f.restype=ctypes.c_int"
              "f('abcde')"

  1000000 loops, best of 3: 1.57 usec per loop

Finally I have tested passing multiple parameters into the function.
One of the parameter is passed by reference in order to return a
value. Performance decrease as the number of parameter increase.

  $ timeit -s "charAt = lambda s, size, pos: s[pos]"
           -s "s='this is a test'"
              "charAt(s, len(s), 1)"

  1000000 loops, best of 3: 0.758 usec per loop

  $ timeit -s "import mylib; s='this is a test'"
              "mylib.py_charAt(s, len(s), 1)"

  1000000 loops, best of 3: 0.929 usec per loop

  $ timeit -s "import ctypes"
           -s "dll = ctypes.CDLL('mylib.pyd')"
           -s "s='this is a test'"
           -s "ch = ctypes.c_char()"
              "dll.charAt(s, len(s), 1, ctypes.byref(ch))"

  100000 loops, best of 3: 2.5 usec per loop

One style of coding that improve the performance somewhat is to build
a C struct to hold all the parameters.

  $ timeit -s "from test_mylib import dll, charAt_param"
           -s "s='this is a test'"
           -s "obj = charAt_param(s=s, size=len(s), pos=3, ch='')"
              "dll.charAt_struct(obj)"

  1000000 loops, best of 3: 1.71 usec per loop

This may work because most of the fields in the charAt_param struct
are invariant in the loop. Having them in the same struct object save
them from getting rebuilt each time.

My overall observation is that ctypes function has an overhead that is
2 to 3 times to a similar C extension function. This may become a
limiting factor if the function calls are fine grained. Using ctypes
for performance enhancement is a lot more productive if the interface
can be made to medium or coarse grained.

A snapshot of the source code used for testing is available for
download

  http://tungwaiyip.info/blog/2009/07/16/ctype_performance_benchmark

Wai Yip Tung


From aurora00 at gmail.com  Fri Jul 17 00:03:14 2009
From: aurora00 at gmail.com (Wai Yip)
Date: Thu, 16 Jul 2009 21:03:14 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <f9e8a620-40ee-4981-82ea-29184f9ef2b1@f20g2000prn.googlegroups.com>

I think Diez' example show this work automatically in Unix. In my case
I use Windows. I use the multiprocessing.Array to share data in shared
memory. multiprocessing.Array has a limitation that it can only
reference simple C data types, not Python objects though.

Wai Yip Tung


From crazypangolin at gmail.com  Fri Jul 17 00:44:26 2009
From: crazypangolin at gmail.com (aj)
Date: Thu, 16 Jul 2009 21:44:26 -0700 (PDT)
Subject: error when compiling source on linux
Message-ID: <1c8d7530-873b-4f52-8d0f-21a6b79de339@p9g2000vbl.googlegroups.com>

when I try to compile Python 2.6 from source code on ubuntu, I get the
message
/usr/bin/ld: cannot open output file python: Is a directory
collect2: ld returned 1 exit status
make: *** [python] Error 1
PLEASE HELP!


From aahz at pythoncraft.com  Fri Jul 17 01:08:31 2009
From: aahz at pythoncraft.com (Aahz)
Date: 16 Jul 2009 22:08:31 -0700
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
Message-ID: <h3p10f$164$1@panix3.panix.com>

In article <mailman.3221.1247757153.8015.python-list at python.org>,
Gabriel Rossetti  <gabriel.rossetti at arimaz.com> wrote:
>
>I am using threading.Condition.wait(timeout) and was surprised to see 
>that there is no return value nor an exception when wait() is used w/ a 
>timeout. How am I supposed to know if it was notified or if it timed out?

What are you trying to do?  Maybe your purpose would be better suited to
using a Queue?  (Yes, Queue is a hammer in search of a nail, but most
threading problems are easier if you treat them as nails.)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From alan.isaac at gmail.com  Fri Jul 17 01:19:50 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Fri, 17 Jul 2009 05:19:50 GMT
Subject: invoke method on many instances
Message-ID: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>

As a recurrent situation, I need to invoke the same method
on many instances.  Speed matters, but the solution should
be pure Python.  Is the following convenience function
a reasonable approach?

def apply2(itr, methodname, *args, **kwargs):
    f = operator.methodcaller(methodname, *args, **kwargs)
    for item in itr:
        f(item)

(Comment: in the case at hand, the methods return None.)

Thank you,
Alan Isaac




From contact at xavierho.com  Fri Jul 17 01:31:28 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 13:31:28 +0800
Subject: Try... except....Try again?
Message-ID: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>

I have a simple class that generates prime numbers, using memorisation and
iteration to generate the next prime number.

In the class, I have defined a function that gives, say, the 5th prime
number. Or the 1000th, it's still very fast. But the code isn't what I
really like.

    def nPrime(self, n):
        "Returns nth prime number, the first one being 2, where n = 0. When
n = 1, it returns 3."
        while True:
            try:
                return self.primes[n]
            except:
                self.next()

The next() function generates the next prime, and appends it into primes.
This way, it keeps trying to append until the nth prime requested exist, and
returns it.

My problem is that it's a "While True" loop, which I get a lot of "Don't do
it!" In the light of making the code better, what could I do?

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/3fb273f6/attachment-0001.html>

From gabriel.rossetti at arimaz.com  Fri Jul 17 02:12:38 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 17 Jul 2009 08:12:38 +0200
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <26ddd1750907161422n5b640a48pbbf9325dd05a699d@mail.gmail.com>
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<a7364d61-4681-4901-9535-ddefa0761667@b15g2000yqd.googlegroups.com>
	<26ddd1750907161422n5b640a48pbbf9325dd05a699d@mail.gmail.com>
Message-ID: <4A601656.1070802@arimaz.com>

Maxim Khitrov wrote:
> On Thu, Jul 16, 2009 at 5:00 PM, Carl Banks<pavlovevidence at gmail.com> wrote:
>   
>> On Jul 16, 8:12 am, Gabriel Rossetti <gabriel.rosse... at arimaz.com>
>> wrote:
>>     
>>> Hello everyone,
>>>
>>> I am using threading.Condition.wait(timeout) and was surprised to see
>>> that there is no return value nor an exception when wait() is used w/ a
>>> timeout. How am I supposed to know if it was notified or if it timed out?
>>>       
>> That's a good question.  Condition.wait seems to violate an invariant
>> if it can return without having acquired the underlying lock.  And if
>> it does the least it could do is to return a status so you know if you
>> have to skeddadle.
>>
>> Workaround is to use the _is_owned() method of Condition to see if you
>> are the owner of the condition, but this method is undocumented.
>>
>> cond = Condition()
>> ...
>> cond.acquire()
>> while not ok_to_proceed():
>>    cond.wait()
>>    if not cond._is_owned():
>>        # must've timed out
>>        raise TimeOutException
>> operate()
>> cond.release()
>>     
>
> You will always be the owner of the condition whether it times out or
> your thread is notified. This doesn't solve the problem. As an aside,
> the implementation of wait() is rather poor in any case; the sleep
> function should not be used for the purpose of waiting for an event.
>
> Depending on what platform you are using, I can offer two solutions.
> The simplest one is to subclass Condition and override the wait
> method. Just copy the code as it is, but modify the end of the
> function to look like this:
>
>                 if not gotit:
>                     if __debug__:
>                         self._note("%s.wait(%s): timed out", self, timeout)
>                     try:
>                         self.__waiters.remove(waiter)
>                     except ValueError:
>                         pass
>                     return False
>                 else:
>                     if __debug__:
>                         self._note("%s.wait(%s): got it", self, timeout)
>                     return True
>
> The two return statements will tell you whether you timed out ("if not
> gotit" condition), or were notified ("else").
>
> The better way to solve this and the other problem that I mentioned is
> to use native OS events. This is what I had to do for a recent
> project. I used pywin32 extension to completely rewrite Event,
> Condition, and Timer classes to use a true event-based approach. In
> the process of the rewrite I also modified some functionality, such as
> returning True of False from wait().
>
> Unfortunately, I'm not able to post this code right now, though I can
> try and get permission to do so a bit later. If you are writing
> software for Windows, then simply take a look at win32event module.
> CreateEvent, SetEvent, ResetEvent, WaitForSingleObject are all the
> Windows functions that you need to reimplement threading.Event. Using
> the new event class you can implement a proper Condition.wait() method
> (hint: use new events rather than locks to wait for notification).
>
> If you are on Linux or BSD, I can't help you. I'm sure that there is
> some equivalent functionality that you may be able to access using
> ctypes. Exactly how to do it, however, is not something that I can
> help you with right now.
>
> - Max
>   

Thank you, I will try that. I am coding for Linux, Mac & Windows (and 
any POSIX platform, but right now I support only those three).

Gabriel


From koranthala at gmail.com  Fri Jul 17 02:13:51 2009
From: koranthala at gmail.com (koranthala)
Date: Thu, 16 Jul 2009 23:13:51 -0700 (PDT)
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com> 
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com> 
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl> 
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
Message-ID: <10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>

> That test was designed to treat None as a boolean False, without
> noticing that numeric 0 is also treated as False and could make the
> test do the wrong thing.  This is an extremely common type of error.

Actually, I felt that 0 not being considered False would be a better
option.
I had lot of instances where 0 is a valid value and always I had to
put checks specifically for that.
For me, None and False should be equal to False in if checks, every
thing else being considered True.

Can someone let me know why 0 is considered equal to False?
There should be real good reasons for it, only that I cannot think of
one.


From gabriel.rossetti at arimaz.com  Fri Jul 17 02:25:23 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 17 Jul 2009 08:25:23 +0200
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <m21voguvxz.fsf@cs.uu.nl>
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
Message-ID: <4A601953.5000603@arimaz.com>

Piet van Oostrum wrote:
>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>             
>
>   
>> GR> Hello everyone,
>> GR> I am using threading.Condition.wait(timeout) and was surprised to see that
>> GR> there is no return value nor an exception when wait() is used w/ a timeout.
>> GR> How am I supposed to know if it was notified or if it timed out?
>>     
>
> Normally you wouldn't have to know. The logic of your program should be
> such that you wait until a certain condition is satisfied. After each
> wait you usually check that condition anyway, like:
>
> while (some_condition_satisfied):
>     cond_var.wait()
>
> The only exception could be if there is a 1-1 relation between a single
> waiter and a single notifier. I that case you can usually use if instead
> of while (but it does depend of the logic of the notifier).
>   

I have a 1-1 relation, I have a thread reading msgs from a network 
socket and a method waiting for an answer to arrive (see my thread 
"Threading.Condition problem"). I would like to be able to have a 
timeout as to not block forever, so the idea is to check if I returned 
because of a timeout or not.

> So in case of using a timeout you can check the desired condition after
> the wait and decide what to do. If the condition was not satisfied you
> probably want to do something special, like error handling, or do
> something else first and then retry the wait.
>
> There could be situations where this doesn't work, however. For example
> if you wait until a queue is not empty, and the notify is done when
> something is inserted in the queue, another thread may sneak in while
> you are waiting and snatch the inserted item just before your thread
> continues after the wait. In that case you can't distinguish between a
> timeout and a snatcher.
>
> So it all depends on what your use case is.
>
> (Java's wait doesn't return anything either.)
>   


From __peter__ at web.de  Fri Jul 17 02:28:46 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 17 Jul 2009 08:28:46 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com> <h3obqg$aru$1@ger.gmane.org>
	<mailman.3246.1247792169.8015.python-list@python.org>
Message-ID: <h3p5mm$o6s$01$1@news.t-online.com>

Terry Reedy wrote:

> Terry Reedy wrote:
> 
>>> $ file tmp.ps
>>> tmp.ps: PostScript document text conforming DSC level 3.0, type EPS
>>>
>>> Try changing the file extension from .ps to .eps.
>> 
>> I will. Thank you.
> 
> I tried it. Unfortunately, OOo does not open it correctly. It just
> displays the first three lines of metadate - Title, Creator, Date -- as
> image text. Photoshop does read the image, and does an ok job of
> conversion once anti-aliasing is turned off.

I snatched some code from the module and modified it to save a sample image:

from turtle import *

def switchpen():
    if isdown():
        pu()
    else:
        pd()

def demo2():
    """Demo of some new features."""
    speed(1)
    st()
    pensize(3)
    setheading(towards(0, 0))
    radius = distance(0, 0)/2.0
    rt(90)
    for _ in range(18):
        switchpen()
        circle(radius, 10)
    write("wait a moment...")
    while undobufferentries():
        undo()
    reset()
    lt(90)
    colormode(255)
    laenge = 10
    pencolor("green")
    pensize(3)
    lt(180)
    for i in range(-2, 16):
        if i > 0:
            begin_fill()
            fillcolor(255-15*i, 0, 15*i)
        for _ in range(3):
            fd(laenge)
            lt(120)
        laenge += 10
        lt(15)
        speed((speed()+1)%12)
    end_fill()

    lt(120)
    pu()
    fd(70)
    rt(30)
    pd()
    color("red","yellow")
    speed(0)
    fill(1)
    for _ in range(4):
        circle(50, 90)
        rt(90)
        fd(30)
        rt(90)
    fill(0)
    lt(90)
    pu()
    fd(30)
    pd()
    shape("turtle")

    tri = getturtle()
    tri.resizemode("auto")
    turtle = Turtle()
    turtle.resizemode("auto")
    turtle.shape("turtle")
    turtle.reset()
    turtle.left(90)
    turtle.speed(0)
    turtle.up()
    turtle.goto(280, 40)
    turtle.lt(30)
    turtle.down()
    turtle.speed(6)
    turtle.color("blue","orange")
    turtle.pensize(2)
    tri.speed(6)
    setheading(towards(turtle))
    count = 1
    while tri.distance(turtle) > 4:
        turtle.fd(3.5)
        turtle.lt(0.6)
        tri.setheading(tri.towards(turtle))
        tri.fd(4)
        if count % 20 == 0:
            turtle.stamp()
            tri.stamp()
            switchpen()
        count += 1
    tri.write("CAUGHT! ", font=("Arial", 16, "bold"), align="right")

if __name__ == "__main__":
    demo2()
    Screen().getcanvas().postscript(file="demo2.eps")

I could successfully insert the picture into Writer.

I'm on Kubuntu 9.04 with Python 2.6.2 and OpenOffice 3.0.1.
 
> Hmmm. Crazy idea... in
> 
http://us.pycon.org/media/2009/talkdata/PyCon2009/065/SevenWaysToUseTurtle-
PyCon2007.pdf
> Gregor Lingl says that turtle.py has been ported to pygame and jython as
> back ends. It should be possible to instead send output to a file
> instead of an on-screen canvas. Run a program to screen. When output
> looks right, return with a different parameter to send to file.
> 
> For instance, an OpenDocumentDrawing file (.odd) using odfpy.
> This assumes that there are elements corresponding to each turtle
> command. Or at least that the fit is close enough.

I can see nothing crazy about that.

But still, turtle is an educational tool, its main advantage is that it can 
show beginners how the image is generated.

If you want to generate high-quality graphics easily you need different 
primitives.

http://cairographics.org

has Python bindings, but I don't know if it's available on Windows.

Peter



From clp2 at rebertia.com  Fri Jul 17 02:30:39 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 16 Jul 2009 23:30:39 -0700
Subject: Einstein summation notation (was: question of style)
In-Reply-To: <10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <50697b2c0907162330m60327179j6f7fcf0427beac3c@mail.gmail.com>

On Thu, Jul 16, 2009 at 11:13 PM, koranthala<koranthala at gmail.com> wrote:
>> That test was designed to treat None as a boolean False, without
>> noticing that numeric 0 is also treated as False and could make the
>> test do the wrong thing. ?This is an extremely common type of error.
>
> Actually, I felt that 0 not being considered False would be a better
> option.
> I had lot of instances where 0 is a valid value and always I had to
> put checks specifically for that.
> For me, None and False should be equal to False in if checks, every
> thing else being considered True.
>
> Can someone let me know why 0 is considered equal to False?
> There should be real good reasons for it, only that I cannot think of
> one.

* Because that's how C does/did it (primary motivation)
- Because if Boolean algebra is implemented using numbers, False is 0
- Because philosophically, 0 is the "empty" or null value for numbers,
        and empty values are by convention considered false in Python
- Because it's the behavior people want 75% of the time.

FWIW, your paradigm of true/false is used by Lisp and Lisp wannabes
such as Ruby.

Cheers,
Chris
-- 
http://blog.rebertia.com


From __peter__ at web.de  Fri Jul 17 02:58:40 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 17 Jul 2009 08:58:40 +0200
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <h3p7en$n4f$02$1@news.t-online.com>

Ben Finney wrote:

> Howdy all,
> 
> The following is a common idiom::
> 
>     class FooGonk(object):
>         def frobnicate(self):
>             """ Frobnicate this gonk. """
>             basic_implementation(self.wobble)
> 
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
> 
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
> 
> Ideally there would be a way to specify that the docstring should be
> inherited. The best I can come up with is::
> 
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>         frobnicate.__doc__ = FooGonk.frobnicate.__doc__
> 
> but that violates DRY (the association between BarGonk and FooGonk is
> being repeated), puts the docstring assignment awkwardly after the end
> of the method instead of at the beginning where docstrings normally go,
> and reads poorly besides.
> 
> What is the most Pythonic, DRY-adherent, and preferably least-ugly
> approach to override a method, but have the same docstring on both
> methods?

Just thinking aloud: Write a patch for pydoc that looks up the base-class 
documentation.

B.f.__doc__ will continue to return None, but

help(B.f) will show something like

    No documentation available for B.f. 

    Help for A.f:
    yadda yadda


Of course that might be misleading when A.f and B.f are up to something 
completely different...

Peter



From nobody at nowhere.com  Fri Jul 17 03:20:15 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 17 Jul 2009 08:20:15 +0100
Subject: UnicodeEncodeError: 'ascii' codec can't encode character	u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<mailman.3258.1247801202.8015.python-list@python.org>
Message-ID: <pan.2009.07.17.07.20.15.547000@nowhere.com>

On Thu, 16 Jul 2009 20:26:39 -0700, akhil1988 wrote:

> Well, you were write: unintentionally I removed strip(). But the problem does
> not ends here:
> 
> I get this error now:
> 
>  File "./temp.py", line 488, in <module>
>     main()
>   File "./temp.py", line 475, in main
>     for line in sys.stdin:
>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>     (result, consumed) = self._buffer_decode(data, self.errors, final)
> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
> data
> 
> for this line:
> ?

Right. You're running in a locale whose encoding is UTF-8, but feeding
data which isn't valid UTF-8 to stdin. If you want to use data with a
different encoding, you need to replace sys.stdin, e.g.:

import sys
import io
sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding = 'iso-8859-1')



From Lacrima.Maxim at gmail.com  Fri Jul 17 03:24:48 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Fri, 17 Jul 2009 00:24:48 -0700 (PDT)
Subject: urllib with x509 certs
References: <19cb6bd9-b9cc-489e-8983-5c0ab08fae71@b15g2000yqd.googlegroups.com>
	<4a4f2307$0$8384$9b622d9e@news.freenet.de>
	<a8e0a282-6522-478b-be3c-0fc8e4587b47@d4g2000yqa.googlegroups.com>
	<4A4F387F.7050804@v.loewis.de>
Message-ID: <c2a05022-0ae2-4518-8e8d-2a29921db8a4@s31g2000yqs.googlegroups.com>

Hello!

I've solved this problem, using pyCurl.
Here is sample code.

import pycurl
import StringIO
b = StringIO.StringIO()
c = pycurl.Curl()
url = 'https://example.com/'
c.setopt(pycurl.URL, url)
c.setopt(pycurl.WRITEFUNCTION, b.write)
c.setopt(pycurl.CAINFO, 'cert.crt')
c.setopt(pycurl.SSLKEY, 'mykey.key')
c.setopt(pycurl.SSLCERT, 'mycert.cer')
c.setopt(pycurl.SSLKEYPASSWD , 'pass phrase')
c.perform()

This also allow to specify CA, so your requests are more secure then
with urllib.

With regards, Max.


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:28:32 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:28:32 GMT
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <02701951$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 23:13:51 -0700, koranthala wrote:

>> That test was designed to treat None as a boolean False, without
>> noticing that numeric 0 is also treated as False and could make the
>> test do the wrong thing.  This is an extremely common type of error.
> 
> Actually, I felt that 0 not being considered False would be a better
> option.
> I had lot of instances where 0 is a valid value and always I had to put
> checks specifically for that.
> For me, None and False should be equal to False in if checks, every
> thing else being considered True.

I believe it would be a mistake for None == False to return True.

As far as having only None and False to be considered equivalent in truth 
contexts, that's awfully limiting. It is very useful to be able to write 
e.g.:

if header or body or footer:
    print assemble_page(header, body, footer)

and have empty strings to be equivalent to False.


Lisp and (I think) Ruby behaves as you want. Python doesn't. We think 
it's Lisp and Ruby that got it wrong :)


> Can someone let me know why 0 is considered equal to False? There should
> be real good reasons for it, only that I cannot think of one.

Having 0 considered false goes back to branching in machine language, 
which I understand are typically. The Null value (e.g. nil in Pascal, nul 
in C) are usually implemented as pointer values equal to an address of 
zero.

It essentially boils down to this: the behaviour of if...else is a 
convention. The language designer might choose to have an explicit 
Boolean type, and prohibit "if None" (e.g. Pascal does this). It might 
choose to treat flags as integers, and branch according to the integer 
being zero (false) or non-zero (true) (e.g. Forth does this). Python 
allows any object to be tested by if, and branches according to whether 
it is Something or Nothing. It's a logical dichotomy, and treating 0 and 
[] as Something instead of Nothing would make it arbitrary and strange.



-- 
Steven


From http  Fri Jul 17 03:34:00 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 00:34:00 -0700
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <7xljmnahlj.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> It is very useful to be able to write e.g.:
> if header or body or footer:
>     print assemble_page(header, body, footer)
> and have empty strings to be equivalent to False.

Why doesn't assemble_page properly handle the case where header, body,
and footer are all empty?  That would let you eliminate the if.  "Make
sure your code 'does nothing' gracefully" (Kernighan and Plauger).


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:45:08 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:45:08 GMT
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
Message-ID: <02701d35$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:

> As a recurrent situation, I need to invoke the same method on many
> instances.  Speed matters, but the solution should be pure Python.  Is
> the following convenience function a reasonable approach?
>
> def apply2(itr, methodname, *args, **kwargs):
>     f = operator.methodcaller(methodname, *args, **kwargs)
>     for item in itr:
>         f(item)

I don't particularly like your naming conventions, but never mind.

You could also try this:

for obj in objects:
    getattr(obj, methodname)(*args, **kwargs)




See also these recipes from the "Python Cookbook":

http://code.activestate.com/recipes/52289/
http://code.activestate.com/recipes/87370/




-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:52:19 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:52:19 GMT
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
	<87ljmogglz.fsf@benfinney.id.au>
Message-ID: <02701ee5$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 12:58:48 +1000, Ben Finney wrote:

>> Using a decorator in this manner requires repeating the super class
>> name.  Perhaps there is a way to get the bases of BarGonk, but I don't
>> think so, because at the time that the decorator is called, BarGonk is
>> not yet fully defined.
> 
> Yes, I tried a few different ways, but within the decorator it seems the
> function object is quite unaware of what class it is destined for.


When the decorator is called, the function object is just a function 
object, not a method, so there is no concept of "what class it is 
destined for".

>>> def dec(func):
...     print type(func)
...     try:
...             print func.im_class
...     except:
...             print "no im_class"
...     return func
...
>>> class Test(object):
...     @dec
...     def spam(self):
...             pass
...
<type 'function'>
no im_class
>>> type(Test.spam)
<type 'instancemethod'>
>>> Test.spam.im_class
<class '__main__.Test'>


I suppose you could try to determine what namespace you're currently when 
the class is created, but that's surely going to be fragile and messy.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 03:56:07 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 07:56:07 GMT
Subject: TypeError: unbound method
References: <9c8c445f0907161757u38925c8w889807f42278122f@mail.gmail.com>
	<mailman.3248.1247792929.8015.python-list@python.org>
Message-ID: <02701fc9$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 18:08:45 -0700, Chris Rebert wrote:

> You're trying to call an instance method on the class itself, which
> doesn't make sense.

Oh I don't know, people do it all the time -- just not the way the OP 
did :)

> You need to first create an instance of the class to invoke the method
> on. i.e.:
> 
> instance = TheClass(constuctor_arguments_here)
> var1 = instance.method()

Or explicitly pass an instance to the method when calling from the class:

TheClass.method(TheClass(constuctor_arguments_here))


Which strangely enough, is useful at times.

class K(parent):
    def method(self, args):
        x = parent.method(self, args)
        return x + 1



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 04:06:22 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 08:06:22 GMT
Subject: How to check if any item from a list of strings is in a big 
	string?
References: <bf87ea0b-e875-4cb7-b221-62057b7b2767@s31g2000yqs.googlegroups.com>
	<pan.2009.07.10.03.07.08@REMOVE.THIS.cybersource.com.au>
	<mailman.3224.1247760199.8015.python-list@python.org>
Message-ID: <0270222f$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 11:02:57 -0500, Pablo Torres N. wrote:

> On Thu, Jul 9, 2009 at 22:07, Steven
> D'Aprano<steven at remove.this.cybersource.com.au> wrote:
>> On Thu, 09 Jul 2009 18:36:05 -0700, inkhorn wrote:
>>
>>> def list_items_in_string(list_items, string):
>>> ? ? for item in list_items:
>>> ? ? ? ? if item in string:
>>> ? ? ? ? ? ? return True
>>> ? ? return False
>> ...
>>> Any ideas how to make that function look nicer? :)
>>
>> Change the names. Reverse the order of the arguments. Add a docstring.
>>
>>
> Why reverse the order of the arguments? Is there a design principle
> there?

It's just a convention. Before strings had methods, you used the string 
module, e.g.:

string.find(source, target)
=> find target in source

This became source.find(target).

In your function:

list_items_in_string(list_items, string)

"list_items" is equivalent to target, and "string" is equivalent to 
source. It's conventional to write the source first.



-- 
Steven


From piet at cs.uu.nl  Fri Jul 17 04:12:52 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:12:52 +0200
Subject: question of style
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <m2my73u3qz.fsf_-_@cs.uu.nl>

>>>>> koranthala <koranthala at gmail.com> (k) wrote:

>>> That test was designed to treat None as a boolean False, without
>>> noticing that numeric 0 is also treated as False and could make the
>>> test do the wrong thing.  This is an extremely common type of error.

>k> Actually, I felt that 0 not being considered False would be a better
>k> option.
>k> I had lot of instances where 0 is a valid value and always I had to
>k> put checks specifically for that.
>k> For me, None and False should be equal to False in if checks, every
>k> thing else being considered True.

>k> Can someone let me know why 0 is considered equal to False?
>k> There should be real good reasons for it, only that I cannot think of
>k> one.

Originally Python didn't have booleans. Integers were used instead (but
not exclusively). 0 was False, everything else True (with a slight
preference for 1 as True). Same as in C. Nowadays this is reflected in
bool being a subtype of int with False == 0 and True == 1. Actually it
is even closer: False and True are just 0 and 1 cast to bool, so to say.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From oisin.mulvihill at gmail.com  Fri Jul 17 04:14:45 2009
From: oisin.mulvihill at gmail.com (Oisin Mulvihill)
Date: Fri, 17 Jul 2009 09:14:45 +0100
Subject: ann: servicestation - run your linux/mac services on windows without
	needing pywin...
Message-ID: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>

Hi There,

I gave a lightning talk about my ServiceStation project at Europython  
2009. While it
isn't written in Python (C++/Windows), I did write it with python in  
mind. Its
released under the CDDL license.

I'm hoping it will be of use to other Python users who will need to  
run their services
on windows, but don't want to learn much/anything about windows  
service programming.

The ServiceStation blurb is:

   ServiceStation allows you to run arbitrary programs as a
   service on the Windows platform. The program you wish to
   run does not need to be changed to allow it to work with
   ServiceStation or windows services.

   This project was developed with an eye to running Python web
   services on Windows, without the need to use and include Pywin32.
   This meant we could take services running on Linux/Mac and
   run them unmodified on Windows."

If your interested in this check out the projects trac page for docs  
and download

   http://www.foldingsoftware.com/servicestation

All the best,

Oisin



From piet at cs.uu.nl  Fri Jul 17 04:26:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:26:27 +0200
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
Message-ID: <m2iqhru34c.fsf@cs.uu.nl>

There is stil something not clear in your description.

>m> I'm using multiprocessing to spawn several subprocesses, each of which
>m> uses a very large data structure (making it impractical to pass it via
>m> pipes / pickling). I need to allocate this structure once when the
>m> process is created and have it remain in memory for the duration of
>m> the process. 

I have read this as that every subprocess has its own large
data structure and that there is no connection between these.

But seeing where the discussion is going I guess there might be
different interpretations. So can you enlighten us how the situation is?

1. Each subprocess has a copy of a data structure that is prepared by the
   master process. Therefore you want it to be passed by the fork
   1a. the data structure is constant i.e. the subprocess doesn't change it
   1b. the subprocess makes changes in its copy
2. Each subprocess has a seperate data structure not equal to the others
3. Something else.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mail at timgolden.me.uk  Fri Jul 17 04:34:27 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 17 Jul 2009 09:34:27 +0100
Subject: ann: servicestation - run your linux/mac services on windows
	without	needing pywin...
In-Reply-To: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>
References: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>
Message-ID: <4A603793.3070803@timgolden.me.uk>

Oisin Mulvihill wrote:
> Hi There,
> 
> I gave a lightning talk about my ServiceStation project at Europython 
> 2009. While it
> isn't written in Python (C++/Windows), I did write it with python in 
> mind. Its
> released under the CDDL license.
> 
> I'm hoping it will be of use to other Python users who will need to run 
> their services
> on windows, but don't want to learn much/anything about windows service 
> programming.

> If your interested in this check out the projects trac page for docs and download
>   http://www.foldingsoftware.com/servicestation 

It's not clear at a glance how this differs from, say, the
venerable SRVANY.EXE and a slew of other "Run-things-as-a-service"
programs. Absolutely not wishing to be disparaging, but what
is servicestation offering to distinguish itself?

TJG


From stefan_ml at behnel.de  Fri Jul 17 04:35:54 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Fri, 17 Jul 2009 10:35:54 +0200
Subject: ctype performance benchmark
In-Reply-To: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
Message-ID: <4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>

aurora00 at gmail.com wrote:
> My overall observation is that ctypes function has an overhead that is
> 2 to 3 times to a similar C extension function. This may become a
> limiting factor if the function calls are fine grained. Using ctypes
> for performance enhancement is a lot more productive if the interface
> can be made to medium or coarse grained.

I think ctypes is ok for its niche: easy interfacing with C stuff from
straight Python code, without further dependencies. There will always (and
necessarily) be a call overhead involved. Anyone who needs to care about
per-call performance would use something else anyway (do I need to mention
Cython here?)

Stefan


From piet at cs.uu.nl  Fri Jul 17 04:37:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:37:27 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
	<mailman.3261.1247811927.8015.python-list@python.org>
Message-ID: <m2eisfu2m0.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> I have a 1-1 relation, I have a thread reading msgs from a network socket
>GR> and a method waiting for an answer to arrive (see my thread
>GR> "Threading.Condition problem"). I would like to be able to have a timeout
>GR> as to not block forever, so the idea is to check if I returned because of a
>GR> timeout or not.

So that case is easy I think. After the wait just check if the answer
has arrived.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Fri Jul 17 04:47:36 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 10:47:36 +0200
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<mailman.3258.1247801202.8015.python-list@python.org>
Message-ID: <m27hy7u253.fsf@cs.uu.nl>

>>>>> akhil1988 <akhilanger at gmail.com> (a) wrote:

>a> Well, you were write: unintentionally I removed strip(). But the problem does
>a> not ends here:

>a> I get this error now:

>a>  File "./temp.py", line 488, in <module>
>a>     main()
>a>   File "./temp.py", line 475, in main
>a>     for line in sys.stdin:
>a>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>a>     (result, consumed) = self._buffer_decode(data, self.errors, final)
>a> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
>a> data

>a> for this line:
>a> ?

Your Python assumes stdin uses utf-8 encoding, probably because your
locale says so. But it seems the input is not really utf-8 but some
other encoding.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From oisin.mulvihill at gmail.com  Fri Jul 17 05:13:49 2009
From: oisin.mulvihill at gmail.com (Oisin Mulvihill)
Date: Fri, 17 Jul 2009 02:13:49 -0700 (PDT)
Subject: ann: servicestation - run your linux/mac services on windows 
	without needing pywin...
References: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com> 
	<mailman.3264.1247819628.8015.python-list@python.org>
Message-ID: <42b910db-7e71-4f26-81ed-ee6a2f29ca56@26g2000yqk.googlegroups.com>

On Jul 17, 9:34?am, Tim Golden <m... at timgolden.me.uk> wrote:
> Oisin Mulvihill wrote:
> > Hi There,
>
> > I gave a lightning talk about my ServiceStation project at Europython
> > 2009. While it
> > isn't written in Python (C++/Windows), I did write it with python in
> > mind. Its
> > released under the CDDL license.
>
> > I'm hoping it will be of use to other Python users who will need to run
> > their services
> > on windows, but don't want to learn much/anything about windows service
> > programming.
> > If your interested in this check out the projects trac page for docs and download
> > ?http://www.foldingsoftware.com/servicestation
>
> It's not clear at a glance how this differs from, say, the
> venerable SRVANY.EXE and a slew of other "Run-things-as-a-service"
> programs. Absolutely not wishing to be disparaging, but what
> is servicestation offering to distinguish itself?
>
> TJG

Hi There,

I have to admit I didn't come across srvany before. I may not have
used the right google fu the day I decided to do this ;) So maybe it
does all the following, however servicestation distingusihes itself
by:

 * Properly tracking all child processes launched by the command it
runs and closes them on stop/restart.

 * Monitoring the command its running and keeping it alive.

 * Allows you to set the description / name from the config file.

 * It logs useful information to the event viewer so you can see why
it couldn't run the command under its care.

 * Can interact with the desktop or not so you can run programs with a
gui but not actually see it.

 * Does not disconnect the service if you log-out as some runners do.

Thats all I can think of. I should probably add this to this wiki too,

Thanks for prompting me on this.

Oisin




From peter.fodrek at stuba.sk  Fri Jul 17 05:24:59 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Fri, 17 Jul 2009 11:24:59 +0200
Subject: error when compiling source on linux
In-Reply-To: <1c8d7530-873b-4f52-8d0f-21a6b79de339@p9g2000vbl.googlegroups.com>
References: <1c8d7530-873b-4f52-8d0f-21a6b79de339@p9g2000vbl.googlegroups.com>
Message-ID: <200907171124.59610.peter.fodrek@stuba.sk>

On Friday 17 July 2009 06:44:26 aj wrote:
> when I try to compile Python 2.6 from source code on ubuntu, I get the
> message
> /usr/bin/ld: cannot open output file python: Is a directory

This says that there is directory in the sources with same name as will be 
named output

It can only occur when you are not compiling software correctly via INSTALL or 
README file

I think you made 

./configure
make

as compiling process

if this is true try 

mkdir bulid
cd build
../configure
make
make install


Kind regards 

Peter 


From mail at timgolden.me.uk  Fri Jul 17 05:26:09 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Fri, 17 Jul 2009 10:26:09 +0100
Subject: ann: servicestation - run your linux/mac services on windows
	without needing pywin...
In-Reply-To: <42b910db-7e71-4f26-81ed-ee6a2f29ca56@26g2000yqk.googlegroups.com>
References: <11B9E5DD-3E9A-4284-AD26-07CBBFF03F02@gmail.com>
	<mailman.3264.1247819628.8015.python-list@python.org>
	<42b910db-7e71-4f26-81ed-ee6a2f29ca56@26g2000yqk.googlegroups.com>
Message-ID: <4A6043B1.8010500@timgolden.me.uk>

Oisin Mulvihill wrote:
> I have to admit I didn't come across srvany before. 

It's been part of the Windows Resource Kit since way back,
but like many such things is probably known more by word-of-mouth
than by Internet Searchability

>  * Properly tracking all child processes launched by the command it
> runs and closes them on stop/restart.
> 
>  * Monitoring the command its running and keeping it alive.
> 
>  * Allows you to set the description / name from the config file.
> 
>  * It logs useful information to the event viewer so you can see why
> it couldn't run the command under its care.
> 
>  * Can interact with the desktop or not so you can run programs with a
> gui but not actually see it.
> 
>  * Does not disconnect the service if you log-out as some runners do.

Looks very interesting. Definitely put this on the front page,
otherwise people may think as I did that this is just another
srvany clone. 

TJG


From hartley79 at gmail.com  Fri Jul 17 05:59:46 2009
From: hartley79 at gmail.com (hartley)
Date: Fri, 17 Jul 2009 02:59:46 -0700 (PDT)
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<768d13a5-e49c-4d43-8707-df19781e28ea@s15g2000yqs.googlegroups.com> 
	<802e3a33-b4f8-4b7e-b14a-67229979f7e7@k6g2000yqn.googlegroups.com> 
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com> 
	<h3nusa$pcb$1@panix3.panix.com>
Message-ID: <94c1adf3-a25d-4ae5-9f38-7ca8680d022d@b14g2000yqd.googlegroups.com>

On Jul 16, 9:26?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <0afc5c4d-1af5-4d0e-9442-26b51b12e... at m11g2000yqh.googlegroups.com>,
>
> hartley ?<hartle... at gmail.com> wrote:
>
> >If you had loosened up on the sarcasm I would probably have read what
> >you wrote more thoroughly instead of just skimming through it. Thanks
> >for the help, but you should seriously consider doing something with
> >your patronizing attitude.
>
> http://www.mikeash.com/getting_answers.htmlhttp://www.catb.org/~esr/faqs/smart-questions.html

>From "http://www.mikeash.com/getting_answers.html":

How To Ask Questions The Smart Way is pretty condescending, especially
if you already feel insulted by somebody telling you that you need
help asking questions. If you're pointed at a guide with a filename of
smart-questions, that means this person thinks you have stupid
questions, and who needs that?

Cheers mate :)

-Hartley


From ben+python at benfinney.id.au  Fri Jul 17 06:03:29 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 20:03:29 +1000
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<h3p7en$n4f$02$1@news.t-online.com>
Message-ID: <87zlb3fwy6.fsf@benfinney.id.au>

Peter Otten <__peter__ at web.de> writes:

> Just thinking aloud: Write a patch for pydoc that looks up the
> base-class documentation.

That doesn't scale; I want the docstring to be discovered by the normal
interface (the ?__doc__? attribute) by *every* tool that gathers
docstrings from methods.

Also, I want to have this behaviour not for every method missing a
docstring, but only for selected methods.

> Of course that might be misleading when A.f and B.f are up to
> something completely different...

Exactly.

-- 
 \     ?Facts do not cease to exist because they are ignored.? ?Aldous |
  `\                                                            Huxley |
_o__)                                                                  |
Ben Finney


From sion at viridian.paintbox  Fri Jul 17 06:20:34 2009
From: sion at viridian.paintbox (Sion Arrowsmith)
Date: Fri, 17 Jul 2009 10:20:34 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
Message-ID: <SfY7m.5466$875.1940@newsfe20.ams2>

Jack Diederich  <jackdied at gmail.com> wrote:
>It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>dicts also raise an error if you try to LT them.

Since when?

Python 2.5.2 (r252:60911, Jan  4 2009, 17:40:26)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> d1 = dict((str(i), i) for i in range (10))
>>> d2 = dict((str(i), i) for i in range (20))
>>> d1 < d2
True
>>>

(Don't have a 2.6 or 3 to hand.)

Mind you, it makes even less sense for a regular dict than an
OrderedDict. And it's not like d1.items() < d2.items() is a
huge burden, if that's what you want dictionary comparison to
mean.

-- 
\S

   under construction



From jeanmichel at sequans.com  Fri Jul 17 07:06:26 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 17 Jul 2009 13:06:26 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <1247774222.4a5f860ec3cfa@mail.uh.cu>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<mailman.3216.1247751117.8015.python-list@python.org>	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi>	<h3nk10$tvu$1@ger.gmane.org>
	<4A5F5759.4010600@sequans.com>
	<1247774222.4a5f860ec3cfa@mail.uh.cu>
Message-ID: <4A605B32.5080306@sequans.com>

Luis Alberto Zarrabeitia Gomez wrote:
> Quoting Jean-Michel Pichavant <jeanmichel at sequans.com>:
>
>   
>> Emile van Sebille wrote:
>>     
>>> On 7/16/2009 7:04 AM Unknown said...
>>>       
>>>> On 2009-07-16, Emile van Sebille <emile at fenx.com> wrote:
>>>>         
>>>>> daysInAdvance = int(inputVar) or 25
>>>>>           
>>>> I don't get it.  That doesn't work right when inputVar == "0".
>>>>
>>>>         
>>> Aah, but you didn't get to define right.  :)  For that particular 
>>> example 0 is not a valid response.
>>>       
>> When I was talking about such error prone form of boolean operations, I 
>> didn't expect to be right so quickly :p
>>     
>
> What do you mean by being "right so quickly", and "error prone" in this context?
> I would also ask "Unknown" why he believes that "int(intputVar) or 25" doesn't
> work right when inputVar == "0". The only false value that int() may return is
> zero, so the "or 25" clause is there only for that case. I can't see then how
> you think that is an error.
>   

I was saying that using boolean operators with object instead of boolean 
values is error prone, cause no language behaves he same way, and all 
behaviors are conventions difficult to figure out without diving deeply 
into the documentation (or being explained as it happened to me).

I think the initialization trick is an error, because I don't want 
foo(0) to set daysInAdvance to 25. I'll want it to set the attribute to 
0, cause 0 is a valid integer. 0 is a valid integer content, None 
wouldn't be a valid integer content.


JM


From bearophileHUGS at lycos.com  Fri Jul 17 07:11:10 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Fri, 17 Jul 2009 04:11:10 -0700 (PDT)
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
Message-ID: <639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>

Very good, thank you. I'll try it when I can.

Is Psyco3 going to borrow/steal some ideas/code from Unladen Swallow?

The problem I have with Psyco1.6 is that you can't use the normal
profilers to know how much seconds of running time is taken by each
function/method of your code.
Psyco1.6 has a profile() function, but I am not much able to use it
yet.
Can you tell me how to find a sorted list of the running time of all
functions/methods of a Psyco-digested program?

Bye and thank you,
bearophile


From andreengels at gmail.com  Fri Jul 17 07:33:03 2009
From: andreengels at gmail.com (Andre Engels)
Date: Fri, 17 Jul 2009 13:33:03 +0200
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
Message-ID: <6faf39c90907170433y7258eebcyeab03ff3021aaa8a@mail.gmail.com>

On Fri, Jul 17, 2009 at 7:31 AM, Xavier Ho<contact at xavierho.com> wrote:
> I have a simple class that generates prime numbers, using memorisation and
> iteration to generate the next prime number.
>
> In the class, I have defined a function that gives, say, the 5th prime
> number. Or the 1000th, it's still very fast. But the code isn't what I
> really like.
[...]
> My problem is that it's a "While True" loop, which I get a lot of "Don't do
> it!" In the light of making the code better, what could I do?

Where do you get these "Don't do it!"s? As far as I know, "while true"
loops are a very acceptable idiom for programming in Python (and
several other languages).


-- 
Andr? Engels, andreengels at gmail.com


From contact at xavierho.com  Fri Jul 17 07:38:55 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 19:38:55 +0800
Subject: Try... except....Try again?
In-Reply-To: <6faf39c90907170433y7258eebcyeab03ff3021aaa8a@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<6faf39c90907170433y7258eebcyeab03ff3021aaa8a@mail.gmail.com>
Message-ID: <2d56febf0907170438l6e38a503g74c3e0256404bb58@mail.gmail.com>

On Fri, Jul 17, 2009 at 7:33 PM, Andre Engels <andreengels at gmail.com> wrote:

>
> Where do you get these "Don't do it!"s? As far as I know, "while true"
> loops are a very acceptable idiom for programming in Python (and
> several other languages).
>

Hey Andre,

Friends, internet, common sense. Also... "while True" has a bad reputation.
But mostly outside influences.

But if it's okay, it's okay by me.. I can't think of an easier way to code
the "try loop" above, anyhow.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/d1ef7b6e/attachment-0001.html>

From Larry.Martell at gmail.com  Fri Jul 17 08:07:04 2009
From: Larry.Martell at gmail.com (Larry.Martell at gmail.com)
Date: Fri, 17 Jul 2009 05:07:04 -0700 (PDT)
Subject: setup.py not found
Message-ID: <3be2bdce-680d-4b32-ad0c-ef46caf556e9@f10g2000vbf.googlegroups.com>

I'm trying to install a package (cx_Oracle) on a mac running 10.5.7.
I've done this on other platforms, but never on a mac. I followed the
instructions given, but when I try and run setup I get:

Apollo:instantclient_10_2 user$ python setup.py build
/System/Library/Frameworks/Python.framework/Versions/2.5/Resources/
Python.app/Contents/MacOS/Python: can't open file 'setup.py': [Errno
2] No such file or directory

Is there something else I have to install first to have this?

Thanks!


From dstanek at dstanek.com  Fri Jul 17 08:08:48 2009
From: dstanek at dstanek.com (David Stanek)
Date: Fri, 17 Jul 2009 08:08:48 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <h3p7en$n4f$02$1@news.t-online.com>
References: <87r5wggm0y.fsf@benfinney.id.au>
	<h3p7en$n4f$02$1@news.t-online.com>
Message-ID: <de32cc030907170508q60ed5fc4tfce14f7bc11e600e@mail.gmail.com>

On Fri, Jul 17, 2009 at 2:58 AM, Peter Otten<__peter__ at web.de> wrote:
> Ben Finney wrote:
>
>> Howdy all,
>>
>> The following is a common idiom::
>>
>> ? ? class FooGonk(object):
>> ? ? ? ? def frobnicate(self):
>> ? ? ? ? ? ? """ Frobnicate this gonk. """
>> ? ? ? ? ? ? basic_implementation(self.wobble)
>>
>> ? ? class BarGonk(FooGonk):
>> ? ? ? ? def frobnicate(self):
>> ? ? ? ? ? ? special_implementation(self.warble)
>>
>> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>> the method, the original docstring is not associated with it.
>>
>> Ideally there would be a way to specify that the docstring should be
>> inherited. The best I can come up with is::
>>
>> ? ? class BarGonk(FooGonk):
>> ? ? ? ? def frobnicate(self):
>> ? ? ? ? ? ? special_implementation(self.warble)
>> ? ? ? ? frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>>
>> but that violates DRY (the association between BarGonk and FooGonk is
>> being repeated), puts the docstring assignment awkwardly after the end
>> of the method instead of at the beginning where docstrings normally go,
>> and reads poorly besides.
>>
>> What is the most Pythonic, DRY-adherent, and preferably least-ugly
>> approach to override a method, but have the same docstring on both
>> methods?
>
> Just thinking aloud: Write a patch for pydoc that looks up the base-class
> documentation.
>
> B.f.__doc__ will continue to return None, but
>
> help(B.f) will show something like
>
> ? ?No documentation available for B.f.
>
> ? ?Help for A.f:
> ? ?yadda yadda
>
>
> Of course that might be misleading when A.f and B.f are up to something
> completely different...
>

This should never be the case. It violates LSP and would be very confusing to
readers of the code.


-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From dstanek at dstanek.com  Fri Jul 17 08:21:39 2009
From: dstanek at dstanek.com (David Stanek)
Date: Fri, 17 Jul 2009 08:21:39 -0400
Subject: Override a method but inherit the docstring
In-Reply-To: <02701ee5$0$5185$c3e8da3@news.astraweb.com>
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
	<87ljmogglz.fsf@benfinney.id.au>
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <de32cc030907170521m1ab5fe86h16c6e62ca157898d@mail.gmail.com>

On Fri, Jul 17, 2009 at 3:52 AM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Fri, 17 Jul 2009 12:58:48 +1000, Ben Finney wrote:
>
>>> Using a decorator in this manner requires repeating the super class
>>> name. ?Perhaps there is a way to get the bases of BarGonk, but I don't
>>> think so, because at the time that the decorator is called, BarGonk is
>>> not yet fully defined.
>>
>> Yes, I tried a few different ways, but within the decorator it seems the
>> function object is quite unaware of what class it is destined for.
>
>
> When the decorator is called, the function object is just a function
> object, not a method, so there is no concept of "what class it is
> destined for".
>
>>>> def dec(func):
> ... ? ? print type(func)
> ... ? ? try:
> ... ? ? ? ? ? ? print func.im_class
> ... ? ? except:
> ... ? ? ? ? ? ? print "no im_class"
> ... ? ? return func
> ...
>>>> class Test(object):
> ... ? ? @dec
> ... ? ? def spam(self):
> ... ? ? ? ? ? ? pass
> ...
> <type 'function'>
> no im_class
>>>> type(Test.spam)
> <type 'instancemethod'>
>>>> Test.spam.im_class
> <class '__main__.Test'>
>
>
> I suppose you could try to determine what namespace you're currently when
> the class is created, but that's surely going to be fragile and messy.
>

It isn't too bad. I got the idea to use the method's enclosing
scope[1] in my decorator[2] from DecoratorTools. I am working to
remove it because it make me sad, but it does work.

[1] http://code.google.com/p/snake-guice/source/browse/snakeguice/decorators.py#51
[2] http://code.google.com/p/snake-guice/source/browse/snakeguice/decorators.py#58


-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From seldon at katamail.it  Fri Jul 17 08:23:45 2009
From: seldon at katamail.it (Seldon)
Date: Fri, 17 Jul 2009 14:23:45 +0200
Subject: guessing file type
Message-ID: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>

Hello,  I need to determine programmatically a file type from its 
content/extension (much like the "file" UNIX command line utility)

I searched for a suitable Python library module, with little luck. Do 
you know something useful ?

Thanks in advance.
-- 
Seldon


From ben+python at benfinney.id.au  Fri Jul 17 08:28:41 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 17 Jul 2009 22:28:41 +1000
Subject: guessing file type
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
Message-ID: <87iqhrfq86.fsf@benfinney.id.au>

Seldon <seldon at katamail.it> writes:

> Hello,  I need to determine programmatically a file type from its
> content/extension (much like the "file" UNIX command line utility)

The Unix ?file(1)? program does its magic with a library called ?magic?
and a corresponding database.

> I searched for a suitable Python library module, with little luck. Do
> you know something useful ?

This package <URL:http://pypi.python.org/pypi/python-magic> provides
Python bindings to libmagic.

-- 
 \     ?Unix is an operating system, OS/2 is half an operating system, |
  `\    Windows is a shell, and DOS is a boot partition virus.? ?Peter |
_o__)                                                        H. Coffin |
Ben Finney


From python.list at tim.thechases.com  Fri Jul 17 08:36:29 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 17 Jul 2009 07:36:29 -0500
Subject: guessing file type
In-Reply-To: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
Message-ID: <4A60704D.8080803@tim.thechases.com>

> Hello,  I need to determine programmatically a file type from its 
> content/extension (much like the "file" UNIX command line utility)
> 
> I searched for a suitable Python library module, with little luck. Do 
> you know something useful ?

Are you looking for something comprehensive?  Or are you just 
looking for particular file-types that your application can 
handle?  I'd start with the python mimetypes library[1] which 
does detection based on extensions (to which you can add your own 
mappings).  For sniffing by content, there are a wide variety of 
document types, I don't know of any pre-existing library.  The 
first couple bytes can often tell you something, but you'd have 
to go digging into the source for "file" to see what it does.

-tkc

[1]
http://docs.python.org/library/mimetypes.html





From van.lindberg at gmail.com  Fri Jul 17 08:39:22 2009
From: van.lindberg at gmail.com (VanL)
Date: Fri, 17 Jul 2009 07:39:22 -0500
Subject: guessing file type
In-Reply-To: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it>
Message-ID: <h3prdq$r2n$1@ger.gmane.org>

Seldon wrote:
> Hello,  I need to determine programmatically a file type from its 
> content/extension (much like the "file" UNIX command line utility)
> 
> I searched for a suitable Python library module, with little luck. Do 
> you know something useful ?

Python-magic (http://pypi.python.org/pypi/python-magic/0.1) wraps 
libmagic -- the same thing that "file" uses -- but getting it on windows 
is a pain. I have never been able to do it, anyway.

A more cross-platform library with a similar scope is hachoir. Still 
seems to be available from PyPI, but the website seems to have fallen 
off the 'net.



From victorsubervi at gmail.com  Fri Jul 17 09:02:25 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Fri, 17 Jul 2009 10:02:25 -0300
Subject: Auto Send URL
Message-ID: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>

Hi;
I am trying to script code that automatically sends a Web site visitor to an
URL. Specifically, when they enter a value in a search box, I have that form
sent to a script that writes an URL acceptable to Google, then I want to
send the visitor off without him having to click another button. How do I do
this?
TIA,
Victor
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/2b88a291/attachment-0001.html>

From python at mrabarnett.plus.com  Fri Jul 17 09:17:20 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 14:17:20 +0100
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
Message-ID: <4A6079E0.8040003@mrabarnett.plus.com>

Xavier Ho wrote:
> I have a simple class that generates prime numbers, using memorisation 
> and iteration to generate the next prime number.
> 
> In the class, I have defined a function that gives, say, the 5th prime 
> number. Or the 1000th, it's still very fast. But the code isn't what I 
> really like.
> 
>     def nPrime(self, n):
>         "Returns nth prime number, the first one being 2, where n = 0. 
> When n = 1, it returns 3."
>         while True:
>             try:
>                 return self.primes[n]
>             except:
>                 self.next()
> 
> The next() function generates the next prime, and appends it into 
> primes. This way, it keeps trying to append until the nth prime 
> requested exist, and returns it.
> 
> My problem is that it's a "While True" loop, which I get a lot of "Don't 
> do it!" In the light of making the code better, what could I do?
> 
I wouldn't use a bare "except". What if you had written "prims" instead
of "primes"? It would catch AttributeError and produce the next prime, 
repeating until it ran out of memory.



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 09:28:00 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 13:28:00 GMT
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
Message-ID: <02706d8f$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 00:34:00 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> It is very useful to be able to write e.g.: 
>>
>> if header or body or footer:
>>     print assemble_page(header, body, footer)
>>
>> and have empty strings to be equivalent to False.
> 
> Why doesn't assemble_page properly handle the case where header, body,
> and footer are all empty?  That would let you eliminate the if.  "Make
> sure your code 'does nothing' gracefully" (Kernighan and Plauger).

You mean something like this?

def assemble_page(header, body, footer):
    if header or body or footer:
        do_lots_of_expensive_processing()
    else:
        do_nothing_gracefully()

Sure, why not?

Whatever way you do it, my point is that it is very useful to perform 
branching tests on non-Boolean objects. Wherever you put the test, being 
able to write:

    if header or body or footer:

is a huge improvement over:

    if (header != '') or (body != '') or (footer != ''):



-- 
Steven


From edreamleo at charter.net  Fri Jul 17 09:36:59 2009
From: edreamleo at charter.net (Edward K Ream)
Date: Fri, 17 Jul 2009 08:36:59 -0500
Subject: ANN: Leo 4.6 final released
Message-ID: <q8%7m.17824$FP2.4210@newsfe05.iad>

Leo 4.6 final is now available at:
http://sourceforge.net/project/showfiles.php?group_id=3458&package_id=29106

Leo is a text editor, data organizer, project manager and much more. See:
http://webpages.charter.net/edreamleo/intro.html

The highlights of Leo 4.6:
--------------------------

- Cached external files *greatly* reduces the time to load .leo files.
- Leo now features a modern Qt interface by default.
  Leo's legacy Tk interface can also be used.
- New --config, --file and --gui command-line options.
- Leo tests syntax of .py files when saving them.
- Leo can now open any kind of file into @edit nodes.
- @auto-rst nodes allow easy editing of reStructuredText files.
- Properties of commanders, positions and nodes simplify programming.
- Improved Leo's unit testing framework.
- Leo now requires Python 2.5 or later.
- Dozens of small improvements and bug fixes.

Links:
------
Leo:      http://webpages.charter.net/edreamleo/front.html
Forum:    http://groups.google.com/group/leo-editor
Download: http://sourceforge.net/project/showfiles.php?group_id=3458
Bzr:      http://code.launchpad.net/leo-editor/
Quotes:   http://webpages.charter.net/edreamleo/testimonials.html

--------------------------------------------------------------------
Edward K. Ream   email:  edreamleo at yahoo.com
Leo: http://webpages.charter.net/edreamleo/front.html
--------------------------------------------------------------------




From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 09:42:44 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 13:42:44 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com> <h3na3s$qjr$1@ger.gmane.org>
	<mailman.3218.1247752436.8015.python-list@python.org>
Message-ID: <02707103$0$5185$c3e8da3@news.astraweb.com>

On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:

> Python has extended the algebra definition of "or" and "and" top any
> type, but it is so unintuitive (I'm no LISP programmer).

I disagree. The Something/Nothing dichotomy is so intuitive to me that I 
would hate to go back to a language that only accepted booleans as 
arguments to `if`.


> I think than 
> using the short-circuiting mechanism of bool operators along with the 
> python tricks is just error prone and may result in bug difficult to 
> spot, unless you are very aware of all python boolean mechanisms.

In other words, if you don't know how Python behaves, you will make 
mistakes.

Of course you will. That applies to *anything* -- if you don't know how 
it works, you will make mistakes.

Given three result codes, where 0 means "no error" and an arbitrary non-
zero integer means some error, it is simple and easy to write:

failed = result_1 or result_2 or result_3

The equivalent:

failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
# or if you prefer:
succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)

are longer and more difficult to read and easier to get wrong. Even worse 
are tricks like this:

failed = (result_1 + result_2 + result_3) != 0

This obscures the fact that the result codes are flags and makes it seem 
like (flag + flag) is meaningful.



-- 
Steven


From justin.mailinglists at gmail.com  Fri Jul 17 09:58:13 2009
From: justin.mailinglists at gmail.com (Justin Ezequiel)
Date: Fri, 17 Jul 2009 06:58:13 -0700 (PDT)
Subject: guessing file type
References: <4a606b28$0$18938$4fafbaef@reader2.news.tin.it> 
	<mailman.3274.1247834383.8015.python-list@python.org>
Message-ID: <7c7ab0ce-ffea-46da-b495-8ebf8e63ecf6@32g2000yqj.googlegroups.com>

On Jul 17, 8:39?pm, VanL <van.lindb... at gmail.com> wrote:
> Seldon wrote:
> > Hello, ?I need to determine programmatically a file type from its
> > content/extension (much like the "file" UNIX command line utility)
>
> > I searched for a suitable Python library module, with little luck. Do
> > you know something useful ?
>

I've used the magic.py module by "Jason Petrone" before.
http://tinyurl.com/ldho8m


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 10:12:37 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 14:12:37 GMT
Subject: Try... except....Try again?
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
Message-ID: <02707804$0$5185$c3e8da3@news.astraweb.com>

Apologies for breaking threading, but the original post hasn't showed up 
on my ISP's news server.

Xavier Ho wrote:
> I have a simple class that generates prime numbers, using memorisation
> and iteration to generate the next prime number.
[...]
> The next() function generates the next prime, and appends it into
> primes. This way, it keeps trying to append until the nth prime
> requested exist, and returns it.
> 
> My problem is that it's a "While True" loop, which I get a lot of
>> "Don't do it!"

There's nothing wrong with "while True" loops. They are useful in two 
situations:

(1) Where you want to loop forever.

(2) Where you want to loop until some complex event takes place, which 
can't easily be written using "while condition".

Neither of these cases holds for your code, so although there's nothing 
wrong with "while True", in your case I'd avoid it.


> In the light of making the code better, what could I do?


(1) Explicitly loop the correct number of times.
(2) Only catch IndexError.

def nPrime(self, n):
    for i in xrange(len(self.primes), n+1):
        self.next()
    return self.primes[n]



-- 
Steven


From http  Fri Jul 17 10:12:51 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 07:12:51 -0700
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <7xab33s8ik.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> def assemble_page(header, body, footer):
>     if header or body or footer:
>         do_lots_of_expensive_processing()
>     else:
>         do_nothing_gracefully()

Why should the processing be expensive if all three fields are empty?

>     if header or body or footer:
> is a huge improvement over:
>     if (header != '') or (body != '') or (footer != ''):

Doesn't really seem any better.  There's always something like

   if any(p != '' for p in [header, body, footer, otherthing1, ...])

if the number of components gets larger.


From kyrie at uh.cu  Fri Jul 17 10:19:51 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Fri, 17 Jul 2009 10:19:51 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A605B32.5080306@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<1247774222.4a5f860ec3cfa@mail.uh.cu>
	<4A605B32.5080306@sequans.com>
Message-ID: <200907171019.52471.kyrie@uh.cu>

On Friday 17 July 2009 07:06:26 am Jean-Michel Pichavant wrote:
>
> I was saying that using boolean operators with object instead of boolean
> values is error prone, cause no language behaves he same way,

I don't know of many languages that actively promote the duck typing concept, 
are as highly dynamic as python, have the "metaclass" concept, treats almost 
all language concepts as first class citizens (including functions and 
classes), and so on. And don't get me started on assignment (which I consider 
very natural, by the way, but apparently most of the popular languages have 
pretty unnatural assignments).

It is error prone if you are expecting the result to be a bool instead of just
behaving like one (it is certainly unexpected, but you shouldn't be expecting 
to get an instance of certain class anyway, for most of python's operations). 
And it is confusing if you are reading the "int(inputVar) or 25" line and 
have no idea of what it means (but once you know it, it becomes very 
readable, almost plain english).

> and all 
> behaviors are conventions difficult to figure out without diving deeply
> into the documentation (or being explained as it happened to me).

That happens with many new concepts. Welcome to python, I guess... if you are 
willing to shake some of your expectations from previous programming 
languages, you will enjoy it. My [little] experience teaching python tells me 
that "duck typing", "non-enforced encapsulation" and "everything is an 
object" are the hardest to accept for the C# folk at my faculty, but once 
past it, they (the few of them who don't leave the course after that) really 
enjoy the language.

> I think the initialization trick is an error, because I don't want
> foo(0) to set daysInAdvance to 25. I'll want it to set the attribute to
> 0, cause 0 is a valid integer. 0 is a valid integer content, None
> wouldn't be a valid integer content.

Well, that wouldn't be a problem with "or", but with the programmer.

The exact same behaviour could be obtained with

if int(inputValue) == 0:
    inputValue = 25

and no "or" involved.

However, using only

inputValue = inputValue or 25

could have been an error if you only wanted 25 in case inputValue is None.

(the "or trick" implies certain trust in that the object you have in hand has 
a reasonable definition of truth value).

-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From jeanmichel at sequans.com  Fri Jul 17 10:34:57 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 17 Jul 2009 16:34:57 +0200
Subject: missing 'xor' Boolean operator
In-Reply-To: <02707103$0$5185$c3e8da3@news.astraweb.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>
	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>
	<h3na3s$qjr$1@ger.gmane.org>	<mailman.3218.1247752436.8015.python-list@python.org>
	<02707103$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A608C11.1020901@sequans.com>

Steven D'Aprano wrote:
> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>
>
> Given three result codes, where 0 means "no error" and an arbitrary non-
> zero integer means some error, it is simple and easy to write:
>
> failed = result_1 or result_2 or result_3
>
> The equivalent:
>
> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
> # or if you prefer:
> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>
>   
[snip]

This is, I guess, where we disagree. I find the second proposal less 
error prone, and universally understandable unlike the first one. It may 
be verbose, it may look even lame to some people, but in the end this is 
perfectly reliable, because you manipulate only False or True within the 
boolean operations.

The first form does not clearly show what is the failed criteria. It 
just happens by coincidence that in this case the failed criteria 
matches the Nothingness of result_1, result_2, result_3. What if results 
may be 'OK' or 'KO'.

failed = result_1 or result_2 or result_3
won't work.

failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is 
lame but reliable.


JM


From contact at xavierho.com  Fri Jul 17 10:35:24 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 22:35:24 +0800
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
Message-ID: <2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>

oops, wrong address.

When will reply-to tag appear on the Python mailing list? =/

Good idea, Steven and MRAB.

I changed my code to the following:

    def nPrime(self, n):
        "Returns nth prime number, the first one being 2, where n = 0. When
n = 1, it returns 3."
        for x in range(n+2):
            try:
                return self.primes[n]
            except IndexError:
                self.next()

And it's definitely better. Thanks a ton guys.

(n+2 because after looping the maximum number of times, it needs to try
returning the value again.)

It works just as well as the previous version, but slightly safer on my
part... and I can adapt this in my future coding habits.

Thanks again.


Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/b5fa2eaf/attachment-0001.html>

From ethan at stoneleaf.us  Fri Jul 17 10:51:05 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 17 Jul 2009 07:51:05 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A608C11.1020901@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<h3na3s$qjr$1@ger.gmane.org>	<mailman.3218.1247752436.8015.python-list@python.org>	<02707103$0$5185$c3e8da3@news.astraweb.com>
	<4A608C11.1020901@sequans.com>
Message-ID: <4A608FD9.908@stoneleaf.us>

Jean-Michel Pichavant wrote:
> Steven D'Aprano wrote:
> 
>> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>>
>>
>> Given three result codes, where 0 means "no error" and an arbitrary non-
>> zero integer means some error, it is simple and easy to write:
>>
>> failed = result_1 or result_2 or result_3
>>
>> The equivalent:
>>
>> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
>> # or if you prefer:
>> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>>
>>   
> 
> [snip]
> 
> This is, I guess, where we disagree. I find the second proposal less 
> error prone, and universally understandable unlike the first one. 

Careful!  The very few (if any) things in this world that can be 
considered "universally understandable" do *not* include any programming 
language!  :)

> It may 
> be verbose, it may look even lame to some people, but in the end this is 
> perfectly reliable, because you manipulate only False or True within the 
> boolean operations.
> 
> The first form does not clearly show what is the failed criteria. It 
> just happens by coincidence that in this case the failed criteria 
> matches the Nothingness of result_1, result_2, result_3. What if results 
> may be 'OK' or 'KO'.

As the programmer, particularly a Python programmer, you should be 
taking advantage of Python's strengths, of which this is one.  If, as 
you say, some function uses a "something" value to indicate an 
undesirable result, then you have to use something akin to your last 
statement.


~Ethan~

> 
> failed = result_1 or result_2 or result_3
> won't work.
> 
> failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is 
> lame but reliable.
> 
> 
> JM



From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 10:54:53 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 14:54:53 GMT
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
Message-ID: <027081ec$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 07:12:51 -0700, Paul Rubin wrote:

> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
>> def assemble_page(header, body, footer):
>>     if header or body or footer:
>>         do_lots_of_expensive_processing()
>>     else:
>>         do_nothing_gracefully()
> 
> Why should the processing be expensive if all three fields are empty?

Since I haven't specified an implementation for assemble_page, it could 
be doing *anything*. Perhaps it has to talk to a remote database over a 
slow link, perhaps it generates 300 lines of really inefficient HTML code 
with no content, perhaps it sends a print job to a printer which then 
warms up, cleans the print heads, and ejects a blank piece of paper.

Why does it matter? The example is about the `if` test, not about the 
function assemble_page().



-- 
Steven


From jackdied at gmail.com  Fri Jul 17 11:02:09 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Fri, 17 Jul 2009 11:02:09 -0400
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
Message-ID: <b8e622740907170802k24cdb6abm41f781dae9a60236@mail.gmail.com>

On Fri, Jul 17, 2009 at 10:35 AM, Xavier Ho<contact at xavierho.com> wrote:

> I changed my code to the following:
>
> ??? def nPrime(self, n):
> ??????? "Returns nth prime number, the first one being 2, where n = 0. When
> n = 1, it returns 3."
> ??????? for x in range(n+2):
> ??????????? try:
> ??????????????? return self.primes[n]
> ??????????? except IndexError:
> ??????????????? self.next()
>
> And it's definitely better. Thanks a ton guys.
>
> (n+2 because after looping the maximum number of times, it needs to try
> returning the value again.)

def nPrime(self, n):
    while len(self.primes) < n:
         self.next()
    return self.primes[n]

If you use an off-the-shelf prime number generator fucntion[1] that
returns consecutive primes the method collapses into a simple
function.

def nPrime(n, primes=[], next_prime=eratosthenes().next):
    while len(primes) < n:
        primes.append(next_prime())
    return primes[n]

-Jack

[1] http://www.catonmat.net/blog/solving-google-treasure-hunt-prime-number-problem-four/#comment-3075
     There is a deque implementation that is faster still but I can't
find a link.


From python at mrabarnett.plus.com  Fri Jul 17 11:09:03 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 16:09:03 +0100
Subject: Einstein summation notation
In-Reply-To: <10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
Message-ID: <4A60940F.6090604@mrabarnett.plus.com>

koranthala wrote:
>> That test was designed to treat None as a boolean False, without
>> noticing that numeric 0 is also treated as False and could make the
>> test do the wrong thing.  This is an extremely common type of error.
> 
> Actually, I felt that 0 not being considered False would be a better
> option.
> I had lot of instances where 0 is a valid value and always I had to
> put checks specifically for that.
> For me, None and False should be equal to False in if checks, every
> thing else being considered True.
> 
> Can someone let me know why 0 is considered equal to False?
> There should be real good reasons for it, only that I cannot think of
> one.

Python did always have True and False.


From gabriel.rossetti at arimaz.com  Fri Jul 17 11:19:36 2009
From: gabriel.rossetti at arimaz.com (Gabriel Rossetti)
Date: Fri, 17 Jul 2009 17:19:36 +0200
Subject: no return value for threading.Condition.wait(timeout)?
In-Reply-To: <m2eisfu2m0.fsf@cs.uu.nl>
References: <mailman.3221.1247757153.8015.python-list@python.org>	<m21voguvxz.fsf@cs.uu.nl>	<mailman.3261.1247811927.8015.python-list@python.org>
	<m2eisfu2m0.fsf@cs.uu.nl>
Message-ID: <4A609688.9080201@arimaz.com>

Piet van Oostrum wrote:
>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>             
>
>   
>> GR> I have a 1-1 relation, I have a thread reading msgs from a network socket
>> GR> and a method waiting for an answer to arrive (see my thread
>> GR> "Threading.Condition problem"). I would like to be able to have a timeout
>> GR> as to not block forever, so the idea is to check if I returned because of a
>> GR> timeout or not.
>>     
>
> So that case is easy I think. After the wait just check if the answer
> has arrived.
>   
The problem is other answers could arrive that are not the one I want. 
Maybe I could check if I got the answer, if not then check how much time 
has elapsed, and if it's grater or equal to the timeout consider it a 
timeout. I still think a return value would be better though.



From ethan at stoneleaf.us  Fri Jul 17 11:20:41 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 17 Jul 2009 08:20:41 -0700
Subject: Einstein summation notation
In-Reply-To: <7xab33s8ik.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<kmr2uu.d1t@spenarnc.xs4all.nl>	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>	<02701951$0$5185$c3e8da3@news.astraweb.com>	<7xljmnahlj.fsf@ruckus.brouhaha.com>	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
Message-ID: <4A6096C9.4070703@stoneleaf.us>

Paul Rubin wrote:
> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> 
>>def assemble_page(header, body, footer):
>>    if header or body or footer:
>>        do_lots_of_expensive_processing()
>>    else:
>>        do_nothing_gracefully()
> 
> 
> Why should the processing be expensive if all three fields are empty?
> 
> 
>>    if header or body or footer:
>>is a huge improvement over:
>>    if (header != '') or (body != '') or (footer != ''):
> 
> 
> Doesn't really seem any better.  There's always something like
> 
>    if any(p != '' for p in [header, body, footer, otherthing1, ...])
> 
> if the number of components gets larger.

Or if any(p for p in [header, body, footer, whatever, ...])

Which is even nicer!  :)  Particularly if header, et al, are some more 
complicated objects which don't easily generate strings, but do easily 
know whether they are Something or Nothing.

I suppose some of these discussions are based more on one's personal 
requirements (using several languages, just a couple, or just Python), 
and whether one wants to achieve Mastery of Python, or just be 
Proficient.  Neither choice is wrong, and wanting Mastery, of course, 
does not mean not wanting improvements, etc.  It does, however, require 
a deep understanding of not just the mechanics, but the philosophy of 
the language.

Mind you, I am nowhere near Mastery just yet (okay, okay, I have a 
_long_ way to go! ;), but I love the philosophy of Python, it's 
simplicity, and the *entirety* of the Zen.

~Ethan~


From malaclypse2 at gmail.com  Fri Jul 17 11:26:18 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Fri, 17 Jul 2009 11:26:18 -0400
Subject: Einstein summation notation
In-Reply-To: <4A60940F.6090604@mrabarnett.plus.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<4A60940F.6090604@mrabarnett.plus.com>
Message-ID: <16651e80907170826r13856d5ag48eb299b70574450@mail.gmail.com>

On Fri, Jul 17, 2009 at 11:09 AM, MRAB<python at mrabarnett.plus.com> wrote:

> Python did always have True and False.

Only if "always" means "since python 2.2.1".

See: http://www.python.org/doc/2.3/whatsnew/section-bool.html and
http://www.python.org/dev/peps/pep-0285/ for details.

-- 
Jerry


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 11:30:11 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 15:30:11 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com>
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org>
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com> <h3na3s$qjr$1@ger.gmane.org>
	<mailman.3218.1247752436.8015.python-list@python.org>
	<02707103$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3280.1247841310.8015.python-list@python.org>
Message-ID: <02708a32$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 16:34:57 +0200, Jean-Michel Pichavant wrote:

> Steven D'Aprano wrote:
>> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>>
>>
>> Given three result codes, where 0 means "no error" and an arbitrary
>> non- zero integer means some error, it is simple and easy to write:
>>
>> failed = result_1 or result_2 or result_3
>>
>> The equivalent:
>>
>> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0) # or if
>> you prefer:
>> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>>
>>
> [snip]
> 
> This is, I guess, where we disagree. I find the second proposal less
> error prone, and universally understandable unlike the first one. It may
> be verbose, it may look even lame to some people, but in the end this is
> perfectly reliable, because you manipulate only False or True within the
> boolean operations.

Because it is verbose, it is more error-prone. The more code you have to 
write, the more opportunities you have to make mistakes.

(This holds up to a point, beyond which being more and more terse also 
leads to more errors.)

Boolean algebra is notorious for programmer errors. The more complicated 
the boolean expression, the more often programmers get it wrong. The more 
book-keeping they have to do, the easier it is to get it wrong. All those 
(result != 0) comparisons are mere book-keeping, they don't add anything 
to the code except to force the flag to be True or False.



> The first form does not clearly show what is the failed criteria.

Of course it does: at least one of the three result codes is non-zero. As 
a bonus, failed will be assigned the first non-zero result code (if any).

Your preferred form, on the other hand, folds all the possible error 
codes into True, throwing away useful information:

>>> result_1 = 0  # success
>>> result_2 = 0
>>> result_3 = 15  # failure
>>> failure = result_1 or result_2 or result_3
>>> failure
15
>>> failure = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
>>> failure
True



> It
> just happens by coincidence that in this case the failed criteria
> matches the Nothingness of result_1, result_2, result_3. What if results
> may be 'OK' or 'KO'.

Obviously the test you write depends on the data you have to work with. 
Do you think that's surprising?


> failed = result_1 or result_2 or result_3 won't work.

Not in the example you gave, no. Although if I had to work with lots and 
lots of strings of the form 'OK' and 'KO', I'd consider sub-classing 
string:

>>> class OKString(str):
...     def __nonzero__(self):
...         if self == 'OK': return True
...         elif self == 'KO': return False
...         else:
...             raise ValueError('invalid result code')
...
>>>
>>> a = OKString('OK')
>>> b = OKString('KO')
>>> c = OKString('KO')
>>> if a and b and c:
...     print "Success!"
... else:  print "Failed!"
...
Failed!


(I wouldn't bother if I only needed one or two such tests, but if I had 
lots of them, I'd consider it.)

 
> failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is
> lame but reliable.


Yes, it's reliably complicated, reliably easy to get wrong, reliably 
harder to read, and it reliably throws away information.

But apart from those disadvantages, it does the job you want it to do.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 17 11:32:41 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 17 Jul 2009 15:32:41 GMT
Subject: Einstein summation notation
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com> <kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<mailman.3284.1247843327.8015.python-list@python.org>
Message-ID: <02708ac8$0$5185$c3e8da3@news.astraweb.com>

On Fri, 17 Jul 2009 16:09:03 +0100, MRAB wrote:

> Python did always have True and False.

$ python1.5
Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
4.1.2-27)] on linux2
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>> True, False
Traceback (innermost last):
  File "<stdin>", line 1, in ?
NameError: True



-- 
Steven


From mooniitk at gmail.com  Fri Jul 17 11:42:19 2009
From: mooniitk at gmail.com (mayank gupta)
Date: Fri, 17 Jul 2009 17:42:19 +0200
Subject: 'del' function for Dictionary
Message-ID: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>

Hi all,

I wanted to know whether there is a more efficient way to delete an entry
from a dictionary (instead of using the 'del' function), because after
analyzing the time taken by the code, it seems to me that the 'del' function
takes most of the time. I might be incorrect as well.
Kindly help me in this regard.

Cheers,
Mayank

-- 
I luv to walk in rain bcoz no one can see me crying
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/0ebdc9af/attachment-0001.html>

From contact at xavierho.com  Fri Jul 17 11:50:14 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 17 Jul 2009 23:50:14 +0800
Subject: Try... except....Try again?
In-Reply-To: <b8e622740907170802k24cdb6abm41f781dae9a60236@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
	<b8e622740907170802k24cdb6abm41f781dae9a60236@mail.gmail.com>
Message-ID: <2d56febf0907170850w5941170fpa527571f7fc241ef@mail.gmail.com>

On Fri, Jul 17, 2009 at 11:02 PM, Jack Diederich <jackdied at gmail.com> wrote:

>
> If you use an off-the-shelf prime number generator fucntion[1] that
> returns consecutive primes the method collapses into a simple
> function.
>
> def nPrime(n, primes=[], next_prime=eratosthenes().next):
>    while len(primes) < n:
>        primes.append(next_prime())
>    return primes[n]
>
> -Jack
>
> [1]
> http://www.catonmat.net/blog/solving-google-treasure-hunt-prime-number-problem-four/#comment-3075
>     There is a deque implementation that is faster still but I can't
> find a link.


Jack, thanks for the link, I'll definitely look into it.

The function is currently implemented in a class I wrote myself, which is a
generator class that does exactly the same thing in the next() function. I
didn't post the code here because it wasn't in the scope of this thread, but
I'm sure others have done a lot better and much more efficient algorithms.

The nPrime method uses the nature of the iteration and checks if a value
already exists (ie generated before) and return that value; otherwise it
iterates again. This way, I don't have to iterate from n=2 and on every
time, which makes generation time linear.

However, I just gave the link's code a quick try. It was at least 10x times
faster than my code to generate 100000 prime numbers - I'll have a closer
look.

Thanks a great deal.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/b6844c29/attachment-0001.html>

From motoom at xs4all.nl  Fri Jul 17 11:54:47 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Fri, 17 Jul 2009 17:54:47 +0200
Subject: 'del' function for Dictionary
In-Reply-To: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
References: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
Message-ID: <4A609EC7.6060007@xs4all.nl>

mayank gupta wrote:
> after analyzing the time taken by the code,
What code?




From dan.eloff at gmail.com  Fri Jul 17 12:11:18 2009
From: dan.eloff at gmail.com (Eloff)
Date: Fri, 17 Jul 2009 09:11:18 -0700 (PDT)
Subject: Find first matching substring
Message-ID: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>

Almost every time I've had to do parsing of text over the last 5 years
I've needed this function:

def find_first(s, subs, start=None, end=None):
    results = [s.find(sub, start, end) for sub in subs]
    results = [r for r in results if r != -1]
    if results:
        return min(results)

    return -1

It finds the first matching substring in the target string, if there
is more than one match, it returns the position of the match that
occurs at the lowest index in the string.

Has anyone else had problems where they could have applied this
function?

It seems to me that python's find (and rfind, index, rindex) could be
modified (the same way that startswith and endswith have been) to
behave this way if a tuple were passed. Do other's agree that this
would be desirable?

Thanks,
Dan


From http  Fri Jul 17 12:15:17 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 09:15:17 -0700
Subject: Einstein summation notation (was: question of style)
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
	<027081ec$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <7xljmn5lre.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:
> Since I haven't specified an implementation for assemble_page, it could 
> be doing *anything*. Perhaps it has to talk to a remote database over a 
> slow link, perhaps it generates 300 lines of really inefficient HTML code 
> with no content, perhaps it sends a print job to a printer which then 
> warms up, cleans the print heads, and ejects a blank piece of paper.

That sounds like a code smell to me.  If the function is supposed to
print a piece of paper when any of those strings are nonempty, it
should also print one when they are all empty.  Of the different
values a string can have, 'foo', 'bar', and '' are all perfectly good
values and should all be treated the same way.  

If you want an absent string to work differently than a present one,
that's separate from empty vs nonempty, and overloading the empty
string to mean "absent" is another antipattern.  Maybe what you really
want is a list of page constituents that are present:

   page_parts = [header, body, footer]

If all the constituents are absent, then page_parts is the empty list,
so you would just test for page_parts being empty.

> Why does it matter? The example is about the `if` test, not about the 
> function assemble_page().

Because of the notion that the code should "do nothing" gracefully.
The presence of that 'if' test is ungraceful, so its better to look
for ways to eliminate it than slickify it.


From wells at submute.net  Fri Jul 17 12:31:10 2009
From: wells at submute.net (Wells Oliver)
Date: Fri, 17 Jul 2009 11:31:10 -0500
Subject: Question regarding style/design..
Message-ID: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>

Sometimes I see relatively small application, generally task scripts,
written as essentially a list of statements. Other times, I see them neatly
divided into functions and then the "if __name__ == '__main__':" convention.
Is there a preference? Is there an... application scope such that the
preference shifts from the former to the latter? I understand the use of the
__name__ == 'main' convention for building unit tests, but I'm mixed on
using it in scripts/small applications.
Thanks for any thoughts!

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/ec934d8c/attachment-0001.html>

From mabdelkader at gmail.com  Fri Jul 17 12:32:12 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Fri, 17 Jul 2009 12:32:12 -0400
Subject: A multi-threaded file searcher for processing large text files
Message-ID: <148918f0907170932w7f1a7f3br78a70845e9050566@mail.gmail.com>

I'm building a threaded file searcher that uses some of Fredrik Lundh's (
http://effbot.org/zone/wide-finder.htm) suggestions for parsing text very
quickly in pure python, as I have about a 10GB log file to parse every day.
A naiive approach would be to just parse the 1MB chunks, add the results
into a list, and just traverse that list.

I want to take this idea a bit further. I want to process results as they're
being found. A great way to implement this is to use the Queue class that
python provides. My idea is to exploit the iterator protocol to have it
block until a result is found, if any, and return the result until we're
finished parsing the file then we can raise StopIteration.

My idea is sort of similar to a producer / consumer, but it follows
something of this idiom:
  producer produces the file chunks
  consumer consumes the file chunks
     -> consumer parsers the file chunks and produces results
  class waits on the production of the original consumer and processes it as
they come.

I am having a bit of trouble with the concurrency, but I'm using this as an
exercise to understand how concurrency works from a broader scale. I am not
trying to get into a debate of whether this is really needed or a
python-concurrency debate:)

Without further ado, my class is as follows:

class ThreadedFileSearcher(object):
    def __init__(self, filename, rx_pat, blocking_timeout = 10):
        self.name = filename
        self.pattern = rx_pat
        self.blocking_timeout = blocking_timeout

        #need to find a better way to do this with more threads that can
return
        #stable results (aka chunks are in order)
        self._thread_count = 1

        #the queues
        self._results = Queue.Queue()
        self._queue = Queue.Queue()

        #returns the get_chunk() implementation
        self._engine = LogParsingEngine(filename)

        #start acquiring file offsets for the file
        #as daemon threads
        self._initialize_worker_threads(self._prime_queue)

        #experimental...should probably be some type of conditional variable
        self._stop_processing = False

    def __iter__(self):
        #start the worker threads
        self._initialize_worker_threads(self._target_worker)
        return self.next()

    def _initialize_worker_threads(self, callback):
        #should really use just one thread
        for i in xrange(self._thread_count):
            t = threading.Thread(target=callback)
            t.setDaemon(True)
            t.start()

    def _prime_queue(self):
        """put code chunk offsets on the queue"""
        #get_chunks() just returns 1MB offsets in the file
        for chunk in self._engine.get_chunks():
            self._queue.put(chunk)

    def _target_worker(self):
        """code chunk to parse queue"""
        #loop infinitely
        while True:
            try:
                #get next chunk offset from the queue
                start_pos, bytes_to_read = self._queue.get(
                                              timeout=self.blocking_timeout
                                           )
            except (TypeError, Queue.Empty):
                #None was returned from the .get()
                #this will throw a TypeError as it tries to unpack None
                #or the Queue was empty
                self._stop_processing = True
                #exit loop
                break

            #process the cunk here
            f = open(self.name, 'r')
            f.seek(start_pos)
            #find all matching lines in the chunk
            for chunk in self.pattern.findall(f.read(bytes_to_read)):
                #an non-overlapping matches of self.pattern
                #placed on the queue as a string
                self._results.put(chunk)
            f.close()

            #done!
            self._queue.task_done()

    def next(self):
        while True:
            try:
                #wait for the results to be put on
                matchedlist =
self._results.get(timeout=self.blocking_timeout)
            except Queue.Empty:
                #if the worker thread finished
                if self._stop_processing:
                    raise StopIteration
            else:
                self._results.task_done()
                yield matchedlist

To use the following class, I wanted to have some kind of interface like
this:

regex = re.compile("-{3}Processing..-{3}") #---Processing..---
f = ThreadedFileSearcher("LogFile.log", regex)
for line in f:
    #guaranteed to be a line that matches regex
    #process something...
    print line


I am looking for some suggestions, comments, and better ways to modify this.


One thing someone will realize when using this class is that the initial
parsing will be incredibly quick, but if the blocking_timeout is set to 10,
then there will be a 10second wait at the end to test if the worker threads
should set the stop conditions. A glaring hole leading from this is if the
blocking_timeout is set to something like 1second and by the time a user
attempts to iterate over the results, the worker threads will prematurely
stop processing.

Speaking of stop processing, should self._stop_processing be a conditional
variable. Right now it's a boolean, and I think that's pretty hacky. I don't
like the StopIteration stop condition, maybe someone has a better
suggestion?

A future modification I'm looking for is to launch multiple threads that
process different parts of the file (different chunks) and return their
results, probably indexed by their chunk offset. Then I can iterate over
that sequentially. I think that would be a trivial parallel optimization.

Thoughts? Comments?

Thanks very much,

Mahmoud Abdelkader
mahmoud at linux.com
http://blog.mahmoudimus.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/75ba6329/attachment-0001.html>

From emile at fenx.com  Fri Jul 17 12:55:39 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 17 Jul 2009 09:55:39 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A608C11.1020901@sequans.com>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<87fxcxj54d.fsf@busola.homelinux.net>	<4A5E1538.7030107@sequans.com>	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>	<mailman.3186.1247684729.8015.python-list@python.org>	<pan.2009.07.15.23.01.37.844000@nowhere.com>	<4A5EEDAE.3040605@sequans.com>	<h3na3s$qjr$1@ger.gmane.org>	<mailman.3218.1247752436.8015.python-list@python.org>	<02707103$0$5185$c3e8da3@news.astraweb.com>
	<4A608C11.1020901@sequans.com>
Message-ID: <h3qa8s$cn2$1@ger.gmane.org>

On 7/17/2009 7:34 AM Jean-Michel Pichavant said...
> Steven D'Aprano wrote:
>> On Thu, 16 Jul 2009 15:53:45 +0200, Jean-Michel Pichavant wrote:
>>
>>
>> Given three result codes, where 0 means "no error" and an arbitrary non-
>> zero integer means some error, it is simple and easy to write:
>>
>> failed = result_1 or result_2 or result_3
>>
>> The equivalent:
>>
>> failed = (result_1 != 0) or (result_2 != 0) or (result_3 != 0)
>> # or if you prefer:
>> succeeded = (result_1 == 0) and (result_2 == 0) and (result_3 == 0)
>>
>>   
> [snip]
> 
> This is, I guess, where we disagree. I find the second proposal less 
> error prone, and universally understandable unlike the first one. It may 
> be verbose, it may look even lame to some people, but in the end this is 
> perfectly reliable, because you manipulate only False or True within the 
> boolean operations.
> 
> The first form does not clearly show what is the failed criteria. It 
> just happens by coincidence 

No -- it happens by design because the premise is 'where 0 means "no 
error" and an arbitrary non-zero integer means some error'.

> that in this case the failed criteria 
> matches the Nothingness of result_1, result_2, result_3. What if results 
> may be 'OK' or 'KO'.

Which by definition won't happen for the example cited...

> 
> failed = result_1 or result_2 or result_3
> won't work.

... so you certainly wouldn't write a test that couldn't properly 
determine success or failure.

> 
> failed = (result_1 =='KO') or (result_2 =='KO') or (result_3 =='KO') is 
> lame but reliable.

In this case I'd write something that meets the specs of the problem 
your addressing...

failed = 'KO' in (result_1,result_2,result_3)

Emile




From nohics at gmail.com  Fri Jul 17 12:59:47 2009
From: nohics at gmail.com (nohics nohics)
Date: Fri, 17 Jul 2009 17:59:47 +0100
Subject: Regular exprssion for IRC messages
Message-ID: <e4de9e30907170959y4fcae9d3v8e26d9fd94e76f4f@mail.gmail.com>

Hello,

When an IRC client receive a messages, this message in in a special format
defined here: Message format in pseudo
BNF<http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1>(
http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1 ).

For example we can have:

:MyNickName!n=MyUserName at 41.238.129.121 JOIN :#AnIrcChannel
:MyNickName!n=MyUserName at 41.238.129.121 PRIVMSG #AnIrcChannel :Hello here
:MyNickName!n=MyUserName at 41.238.129.121 NICK :TheNewNickName
:holmes.freenode.net 372 UnNickName :- a message here ...

I want to transforme the message format defined in the irc protocole in the
last link, to a regular expression to get the nickname, the username, the
host, the commad, it's arguments if exist, and the message after ":"

I'm programming in python and I have tried this regular expression:

^(:(\w+)(![^ \r\n]+)?(\@[^ \r\n]+)? )?([a-zA-Z]+|\d\d\d)(( [^: \r\n][^
\r\n]*)+)( :[^\r\n]*)?

Python code:

nicknamePattern = re.compile(r'^(:(\w+)(![^ \r\n]+)?(\@[^ \r\n]+)?
)?([a-zA-Z]+|\d\d\d)(( [^: \r\n][^ \r\n]*)+)( :[^\r\n]*)?')
matches = nicknamePattern.search(data)
if matches != None:  print matches.groups()

But it doesn't seems to work all the time. So can you help me to make the
correct regular expression please ?

You can see some example of messages working or not with this pattren (when
I try to connect to an irc server):
http://www.developpez.net/forums/d779736/php/langage/regex/format-message-pseudo-bnf-expression-reguliere/#post4494010
Thanks.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/1bd7667f/attachment-0001.html>

From python.list at tim.thechases.com  Fri Jul 17 13:11:49 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 17 Jul 2009 12:11:49 -0500
Subject: Question regarding style/design..
In-Reply-To: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
Message-ID: <4A60B0D5.6030806@tim.thechases.com>

> Sometimes I see relatively small application, generally task scripts,
> written as essentially a list of statements. Other times, I see them neatly
> divided into functions and then the "if __name__ == '__main__':" convention.
> Is there a preference? Is there an... application scope such that the
> preference shifts from the former to the latter? I understand the use of the
> __name__ == 'main' convention for building unit tests, but I'm mixed on
> using it in scripts/small applications.

This may circle around to the "is Python a scripting language" 
bruhaha a while back.  I tend to skip the __name__ == '__main__' 
in what I'd consider scripts (one-file hacks to solve an 
immediate problem, often disposable or one-use wonders).  However 
for non-scripts (which I'd define as code that has more than one 
source-code file I've written or that I'd have to maintain) and 
for modules, I tend to put in the __name__ guard.

-tkc






From aurora00 at gmail.com  Fri Jul 17 13:15:59 2009
From: aurora00 at gmail.com (Wai Yip)
Date: Fri, 17 Jul 2009 10:15:59 -0700 (PDT)
Subject: ctype performance benchmark
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
	<4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>
Message-ID: <48c15bac-8af2-472d-9bc0-1f19c4bf29cb@g7g2000prg.googlegroups.com>

I started with ctypes because it is the battery included with the
Python standard library. My code is very fluid and I'm looking for
easy opportunity to optimize it. One example is to find the longest
common prefix among two strings. Right now I am comparing it character
by character with pure Python. It seems like an ideal low hanging
fruit. With ctype I can rewriting a few lines of Python into a few
lines of C. All the tools are available and no third party library is
needed.

It turned out the performance fail to match pure Python. This function
is called million of times in an inner loop. The overhead overwhelm
any performance gain with C. Eventually I have found success grouping
the data into larger chunk for each API call. This is what I
originally planned to do anyway. I am only sharing my experience here
that doing fine grained ctype function call has its limitation.

I have looked into Pyrex before and I was quite confused by the fusion
of C and Python langauage. Perhaps it is time for me to give it a
second look. I just heard of Cython now and it also look interesting.
I think it is helpful for both project to articulate more clearly what
they are, how they achieve the performance gain and to give more
guidance on good use cases. On the other hand, perhaps it is just me
are confused because I don't know enough of the Python internal.

Wai Yip


From mydevforums at gmail.com  Fri Jul 17 13:17:19 2009
From: mydevforums at gmail.com (IronyOfLife)
Date: Fri, 17 Jul 2009 10:17:19 -0700 (PDT)
Subject: Installing python-gnutls on Windows
Message-ID: <58825f8b-9665-4a3d-9f0a-7bb559ae195e@p23g2000vbl.googlegroups.com>

Hi,

I'm new to python and would like to request your help installing
python-gnutls on windows. Are there binaries available which can be
installed ?

Looks like the setup.py file which came with the package is for
Debian. I tried modifying it for windows but am still getting errors.

get_options() is not getting the include directories and libraries so
I harcoded the include directories. I'm getting the following error
now:
//-----------------------------------------------------------------------------------
C:\Development\python\python-gnutls-1.1.8>python setup.py build --
compiler=mingw32
running build
running build_py
running build_ext
building 'gnutls.library._gnutls_init' extension
Traceback (most recent call last):
  File "setup.py", line 86, in <module>
    libraries='-lgnutls -lgnutls-extra')])
  File "C:\Python26\lib\distutils\core.py", line 152, in setup
    dist.run_commands()
  File "C:\Python26\lib\distutils\dist.py", line 975, in run_commands
    self.run_command(cmd)

  ....

  File "C:\Python26\lib\distutils\command\build_ext.py", line 471, in
build_exte
nsions
    self.build_extension(ext)

  ...

    depends=ext.depends)
  File "C:\Python26\lib\distutils\ccompiler.py", line 689, in compile
    depends, extra_postargs)
  File "C:\Python26\lib\distutils\ccompiler.py", line 363, in
_setup_compile
    "'include_dirs' (if supplied) must be a list of strings"
TypeError: 'include_dirs' (if supplied) must be a list of strings
//-------------------------------------------------------------------------------------

I would really appreciate your help

Thanks

Ramg


From lodmod.dod at gmail.com  Fri Jul 17 13:20:43 2009
From: lodmod.dod at gmail.com (LoD MoD)
Date: Fri, 17 Jul 2009 10:20:43 -0700
Subject: getopt code NameError exception on logTail.py
Message-ID: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>

I am having trouble extending my option parsing.

Any help is appreciated:


import sys

import getopt

import time


def tail(file):

    while 1:

        where = file.tell()

        line = file.readline()

        if not line:

            time.sleep(1)

            file.seek(where)

        else:

            print line, # already has newline


def main():



    # parse command line options

    try:

        opts, args = getopt.getopt(sys.argv[1:], "hf:", ["help", "filename="
])

    except getopt.error, msg:

        print msg

        print "for help use --help"

        sys.exit(2)

    # process options

    for o, a in opts:

        if o in ("-h", "--help"):

            print __doc__

            sys.exit(0)

        if o in ("-f", "--filename"):

            print "Parsing F argument"

            file = open(filename, 'r')

            print file






    # process arguments

    for arg in args:

        process(arg) # process() is defined elsewhere


if __name__ == "__main__":

    main()

Yields this error:

localhost:src gsery$ python logTail.py  /var/log/system.log
Traceback (most recent call last):
  File "logTail.py", line 52, in <module>
    main()
  File "logTail.py", line 49, in main
    process(arg) # process() is defined elsewhere
NameError: global name 'process' is not defined
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/ef10e2b8/attachment-0001.html>

From mrabarnett at mrabarnett.plus.com  Fri Jul 17 13:24:42 2009
From: mrabarnett at mrabarnett.plus.com (Matthew Barnett)
Date: Fri, 17 Jul 2009 18:24:42 +0100
Subject: Einstein summation notation
In-Reply-To: <02708ac8$0$5185$c3e8da3@news.astraweb.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>	<mailman.3284.1247843327.8015.python-list@python.org>
	<02708ac8$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A60B3DA.7010506@mrabarnett.plus.com>

Steven D'Aprano wrote:
> On Fri, 17 Jul 2009 16:09:03 +0100, MRAB wrote:
> 
>> Python did always have True and False.

Oops! I meant "didn't", of course.
> 
> $ python1.5
> Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
> 4.1.2-27)] on linux2
> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>> True, False
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
> NameError: True
> 


From phily05 at gmail.com  Fri Jul 17 13:28:13 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 10:28:13 -0700 (PDT)
Subject: Propagate import for all modules in a package.
Message-ID: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>

I'm really new to Python and I am absolutely stumped trying to figure
this out. I have searched plenty, but I am either searching for the
wrong keywords or this isn't possible.

What I want to do is have one import be global for the entire package.
Here is an example...

<package>
  __init__.py
  module1.py
  module2.py
  ...
  moduleN.py

I was thinking that I could just, for example, 'from datetime import
datetime' in __init__.py and have the ability to use 'datetime'
anywhere in any of the modules in 'package'.

This didn't work for me. Did I just do something wrong? Is what I am
trying to do possible?

Thanks in advance.


From Scott.Daniels at Acm.Org  Fri Jul 17 13:37:25 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 17 Jul 2009 10:37:25 -0700
Subject: UnicodeEncodeError: 'ascii' codec can't encode character u'\xb7'
	in position 13: ordinal not in range(128)
In-Reply-To: <mailman.3258.1247801202.8015.python-list@python.org>
References: <24509879.post@talk.nabble.com>	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>	<24510222.post@talk.nabble.com>	<4a5ed587$0$1627$742ec2ed@news.sonic.net>	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>	<24522412.post@talk.nabble.com>
	<m2ws68th6f.fsf@cs.uu.nl>	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<mailman.3258.1247801202.8015.python-list@python.org>
Message-ID: <gsKdncY9AMiQKP3XnZ2dnUVZ_hudnZ2d@pdx.net>

akhil1988 wrote:
<mis-ordered reply, bits shown below>>
> Nobody-38 wrote:
>> On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:
...
>>>> In Python 3 you can't decode strings because they are Unicode strings
>>>> and it doesn't make sense to decode a Unicode string. You can only
>>>> decode encoded things which are byte strings. So you are mixing up byte
>>>> strings and Unicode strings.
>>> ... I read a byte string from sys.stdin which needs to converted to unicode
>>> string for further processing.
>> In 3.x, sys.stdin (stdout, stderr) are text streams, which means that they
>> read and write Unicode strings, not byte strings.
>>
>>> I cannot just remove the decode statement and proceed?
>>> This is it what it looks like:
>>>     for line in sys.stdin:
>>>         line = line.decode('utf-8').strip()
>>>         if line == '<page>': #do something here
>>>         ....
>>> If I remove the decode statement, line == '<page>' never gets true. 
>> Did you inadvertently remove the strip() as well?
> ... unintentionally I removed strip()....
> I get this error now:
>  File "./temp.py", line 488, in <module>
>     main()
>   File "./temp.py", line 475, in main
>     for line in sys.stdin:
>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>     (result, consumed) = self._buffer_decode(data, self.errors, final)
> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2: invalid
> data

(1) Do not top post.
(2) Try to fully understand the problem and proposed solution, rather
     than trying to get people to tell you just enough to get your code
     going.
(3) The only way sys.stdin can possibly return unicode is to do some
     decoding of its own.  your job is to make sure it uses the correct
     decoding.  So, if you know your source is always utf-8, try
     something like:

     import sys
     import io

     sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding='utf8')

     for line in sys.stdin:
         line = line.strip()
         if line == '<page>':
             #do something here
         ....

--Scott David Daniels
Scott.Daniels at Acm.Org


From robert.kern at gmail.com  Fri Jul 17 13:45:44 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 17 Jul 2009 12:45:44 -0500
Subject: Question regarding style/design..
In-Reply-To: <4A60B0D5.6030806@tim.thechases.com>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
	<4A60B0D5.6030806@tim.thechases.com>
Message-ID: <h3qdc9$mdc$1@ger.gmane.org>

On 2009-07-17 12:11, Tim Chase wrote:
>> Sometimes I see relatively small application, generally task scripts,
>> written as essentially a list of statements. Other times, I see them
>> neatly
>> divided into functions and then the "if __name__ == '__main__':"
>> convention.
>> Is there a preference? Is there an... application scope such that the
>> preference shifts from the former to the latter? I understand the use
>> of the
>> __name__ == 'main' convention for building unit tests, but I'm mixed on
>> using it in scripts/small applications.
>
> This may circle around to the "is Python a scripting language" bruhaha a
> while back. I tend to skip the __name__ == '__main__' in what I'd
> consider scripts (one-file hacks to solve an immediate problem, often
> disposable or one-use wonders). However for non-scripts (which I'd
> define as code that has more than one source-code file I've written or
> that I'd have to maintain) and for modules, I tend to put in the
> __name__ guard.

I definitely suggest always using the __name__ guard no matter what. Habits are 
important, and it's usually more of a waste of time trying to determine if you 
are writing a "script" or a "program" than it is to just write the clause all 
the time. One of the ex-DivMod guys (Glyph?) has a good blog post on the subject 
of writing docstrings and the Suzuki Method of violin; however, I cannot find 
it. With a good programmer's editor that can do macros or "snippets", this 
particular habit can be basically cost-free.

There are also technical limitations to be aware of. Even if you don't think you 
will ever import the script, other tools might. For example, on Windows, 
multiprocessing needs to import the main module of the parent process in order 
to do some of its operations. If you do not have a __name__ guard, you will go 
into an infinite regress as your subprocesses execute the main code and create 
subsubprocesses until you finally manage to kill them all. Extra fun if it is a 
GUI and you have to click all of the windows closed.

Don't waste half a day trying to figure out why your script mysteriously doesn't 
work. Learn from my mistakes. :-)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From deets at nospam.web.de  Fri Jul 17 13:52:30 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 17 Jul 2009 19:52:30 +0200
Subject: Propagate import for all modules in a package.
In-Reply-To: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
Message-ID: <7cbs2uF275m7mU1@mid.uni-berlin.de>

Phil schrieb:
> I'm really new to Python and I am absolutely stumped trying to figure
> this out. I have searched plenty, but I am either searching for the
> wrong keywords or this isn't possible.
> 
> What I want to do is have one import be global for the entire package.
> Here is an example...
> 
> <package>
>   __init__.py
>   module1.py
>   module2.py
>   ...
>   moduleN.py
> 
> I was thinking that I could just, for example, 'from datetime import
> datetime' in __init__.py and have the ability to use 'datetime'
> anywhere in any of the modules in 'package'.
> 
> This didn't work for me. Did I just do something wrong? Is what I am
> trying to do possible?

Each module has it's own namespace, there is no real global one. So 
there is no obvious and recommended way to do what you want.

You can do it through, by stuffing names into the __builtins__-module, 
which acts as "namespace of last resort"


from datetime import datetime
__builtins__['datetime'] = datetime

However, this is strongly discouraged - you can easily get 
name-conflicts, and undefined behavior in your modules if you rely on this.

Diez


From zaki.rahaman at gmail.com  Fri Jul 17 13:58:20 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 10:58:20 -0700 (PDT)
Subject: Generator Expressions and CSV
Message-ID: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>

Hey all,

I'm really new to Python and this may seem like a really dumb
question, but basically, I wrote a script to do the following, however
the processing time/memory usage is not what I'd like it to be. Any
suggestions?


Outline:
1. Read tab delim files from a directory, files are of 3 types:
install, update, and q. All 3 types contain ID values that are the
only part of interest.
2. Using set() and set.add(), generate a list of unique IDs from
install and update files.
3. Using the set created in (2), check the q files to see if there are
matches for IDs. Keep all matches, and add any non matches (which only
occur once in the q file) to a queue of lines to be removed from teh q
files.
4. Remove the lines in the q for each file. (I haven't quite written
the code for this, but I was going to implement this using csv.writer
and rewriting all the lines in the file except for the ones in the
removal queue).

Now, I've tried running this and it takes much longer than I'd like. I
was wondering if there might be a better way to do things (I thought
generator expressions might be a good way to attack this problem, as
you could generate the set, and then check to see if there's a match,
and write each line that way).




From python at mrabarnett.plus.com  Fri Jul 17 13:59:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 18:59:09 +0100
Subject: Find first matching substring
In-Reply-To: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>
References: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>
Message-ID: <4A60BBED.7040501@mrabarnett.plus.com>

Eloff wrote:
 > Almost every time I've had to do parsing of text over the last 5 years
 > I've needed this function:
 >
 > def find_first(s, subs, start=None, end=None):
 >     results = [s.find(sub, start, end) for sub in subs]
 >     results = [r for r in results if r != -1]
 >     if results:
 >         return min(results)
 >
 >     return -1
 >
 > It finds the first matching substring in the target string, if there
 > is more than one match, it returns the position of the match that
 > occurs at the lowest index in the string.
 >
One possible optimisation for your code is to note that if you find that
one of the substrings starts at a certain position then you're not
interested in any subsequent substring which might start at or after
that position, so you could reduce the search space for each substring
found.

> Has anyone else had problems where they could have applied this 
> function?
> 
> It seems to me that python's find (and rfind, index, rindex) could be
>  modified (the same way that startswith and endswith have been) to 
> behave this way if a tuple were passed. Do other's agree that this 
> would be desirable?
> 
Possibly. I think that allowing a tuple in the partition and rpartition
methods might also be useful.



From marduk at letterboxes.org  Fri Jul 17 13:59:39 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Fri, 17 Jul 2009 13:59:39 -0400
Subject: Propagate import for all modules in a package.
In-Reply-To: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
Message-ID: <1247853579.17425.10.camel@centar>

On Fri, 2009-07-17 at 10:28 -0700, Phil wrote:
> I'm really new to Python and I am absolutely stumped trying to figure
> this out. I have searched plenty, but I am either searching for the
> wrong keywords or this isn't possible.
> 
> What I want to do is have one import be global for the entire package.
> Here is an example...
> 
> <package>
>   __init__.py
>   module1.py
>   module2.py
>   ...
>   moduleN.py
> 
> I was thinking that I could just, for example, 'from datetime import
> datetime' in __init__.py and have the ability to use 'datetime'
> anywhere in any of the modules in 'package'.
> 
> This didn't work for me. Did I just do something wrong? Is what I am
> trying to do possible?
> 

That's not how packages (were designed to) work.  A package is basically
a namespace.  It doesn't do anything special outside of providing a
namespace for common modules.  There are some special features (e.g.
__init__.py which is basically the "body" of the package and '__all__'
which handles wildcard imports of a package) but other than that it's
just a namespace.



From python.list at tim.thechases.com  Fri Jul 17 14:01:44 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 17 Jul 2009 13:01:44 -0500
Subject: Question regarding style/design..
In-Reply-To: <h3qdc9$mdc$1@ger.gmane.org>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>	<4A60B0D5.6030806@tim.thechases.com>
	<h3qdc9$mdc$1@ger.gmane.org>
Message-ID: <4A60BC88.2070703@tim.thechases.com>

Robert Kern wrote:
[sage advice snipped]
> Don't waste half a day trying to figure out why your script
> mysteriously doesn't work. Learn from my mistakes. :-)

I find that's the best type of mistake to learn from:  other
people's ;-)


-tkc


From hannarosie at gmail.com  Fri Jul 17 14:06:27 2009
From: hannarosie at gmail.com (Hanna Michelsen)
Date: Fri, 17 Jul 2009 11:06:27 -0700
Subject: Writing a single list of numbers to a .m (matlab) file
Message-ID: <564970db0907171106q2be0852dg7209a4177f0b265a@mail.gmail.com>

Hi,

I was wondering if I could get some suggestions on how to write a single
list of numbers to a .m file (for matlab) so that I can create a matlab
vector out of the list of numbers from my python program. I have been using
a csv writer to create .m files from lists of lists, but I'm not sure how to
write just a single list to the file. (if I use the same code I've been
using, I get an error: csv.Error sequence expected)

Thanks for the help!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/23a9b4e8/attachment-0001.html>

From python at mrabarnett.plus.com  Fri Jul 17 14:08:16 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 19:08:16 +0100
Subject: getopt code NameError exception on logTail.py
In-Reply-To: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>
References: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>
Message-ID: <4A60BE10.5050905@mrabarnett.plus.com>

LoD MoD wrote:
> I am having trouble extending my option parsing.
> Any help is appreciated:
> 
> import sys
> import getopt
> import time
> 
> def tail(file):
>     while 1:
>         where = file.tell()
>         line = file.readline()
>         if not line:
>             time.sleep(1)
>             file.seek(where)
>         else:
>             print line, # already has newline
> 
> def main():
> 
>     # parse command line options
>     try:
>         opts, args = getopt.getopt(sys.argv[1:], "hf:", ["help", 
> "filename="])
>     except getopt.error, msg:
>         print msg
>         print "for help use --help"
>         sys.exit(2)
>     # process options
>     for o, a in opts:
>         if o in ("-h", "--help"):
>             print __doc__
>             sys.exit(0)
>         if o in ("-f", "--filename"):
>             print "Parsing F argument"
>             file = open(filename, 'r')
>             print file
> 
>         
>             
>     # process arguments
>     for arg in args:
>         process(arg) # process() is defined elsewhere
> 
> if __name__ == "__main__":
>     main()
> 
> Yields this error:
> 
> localhost:src gsery$ python logTail.py  /var/log/system.log
> Traceback (most recent call last):
>   File "logTail.py", line 52, in <module>
>     main()
>   File "logTail.py", line 49, in main
>     process(arg) # process() is defined elsewhere
> NameError: global name 'process' is not defined
> 
The trackback tells you what's wrong: you haven't defined 'process'. The
comment says it's defined elsewhere, but neither I nor Python can see
it! :-)


From emile at fenx.com  Fri Jul 17 14:26:22 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 17 Jul 2009 11:26:22 -0700
Subject: Generator Expressions and CSV
In-Reply-To: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
Message-ID: <h3qfj0$sv3$1@ger.gmane.org>

On 7/17/2009 10:58 AM Zaki said...
<snip>
> Now, I've tried running this and it takes much longer than I'd like. I
> was wondering if there might be a better way to do things 

Suppose, for the sake of argument, that you've written highly efficient 
code.  Then the processing time would already be entirely optimized and 
no improvements possible.  It's running as fast as it can.  We can't help.

On the other hand, maybe you didn't.  In that case, you'll need to 
profile your code to determine where the time is consumed.  At a 
minimum, you'll need to post the slow parts so we can see the 
implementation and suggest improvements.

Emile



From nick at craig-wood.com  Fri Jul 17 14:29:59 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Fri, 17 Jul 2009 13:29:59 -0500
Subject: ctype performance benchmark
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
	<4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>
	<48c15bac-8af2-472d-9bc0-1f19c4bf29cb@g7g2000prg.googlegroups.com>
Message-ID: <slrnh61gce.r2o.nick@irishsea.home.craig-wood.com>

Wai Yip <aurora00 at gmail.com> wrote:
>  I started with ctypes because it is the battery included with the
>  Python standard library. My code is very fluid and I'm looking for
>  easy opportunity to optimize it. One example is to find the longest
>  common prefix among two strings. Right now I am comparing it character
>  by character with pure Python. It seems like an ideal low hanging
>  fruit. With ctype I can rewriting a few lines of Python into a few
>  lines of C. All the tools are available and no third party library is
>  needed.

Yes ctypes is very easy for this and I've used it like this in the
past too.  It makes interfacing C code very easy.

You might consider just writing a plain bit of C code.  If you make a
setup.py too (not hard) then it is very easy to distribute and use on
other platforms.

The Python C API is very easy to use - documentation is extensive.
You need to be very careful with references and the error checking is
boring and tedious!

>  It turned out the performance fail to match pure Python. This function
>  is called million of times in an inner loop. The overhead overwhelm
>  any performance gain with C. Eventually I have found success grouping
>  the data into larger chunk for each API call. This is what I
>  originally planned to do anyway. I am only sharing my experience here
>  that doing fine grained ctype function call has its limitation.

Interesting but not too unexpected - that translation of types is
non-trivial.

>  I have looked into Pyrex before and I was quite confused by the fusion
>  of C and Python langauage. Perhaps it is time for me to give it a
>  second look. I just heard of Cython now and it also look interesting.
>  I think it is helpful for both project to articulate more clearly what
>  they are, how they achieve the performance gain and to give more
>  guidance on good use cases. On the other hand, perhaps it is just me
>  are confused because I don't know enough of the Python internal.

Pyrex evolved/was forked into Cython.

Cython allows you to write a subset of python code that is compiled
into C.  You can also optionally provide some type annotations to get
it to produce better C code at the cost of making your code look less
like python.

I find Cython alternatively brilliant and frustrating!  Sometimes it
works really well, and sometimes I spend hours working out why my
program doesn't compile, or to find out the exact syntax I need to
interface with such and such a library.

I did a C library interfacing project with both ctypes and cython
recently as a comparison.  It came out to be about the same number of
lines of code for both.  I decided to run with the ctypes version as
it was part python.

Here is a short Cython example which interfaces with opendir /
closedir / readdir which python doesn't do natively.  Note the way you
interface with C structures (the real ones are used in the C code -
the annotations just tell cython how to use them).  Note also that
Directory is a class defined in C which I don't think you can't do
with ctypes without a wrapper class.

This compiles into 1320 lines of C, which in turn compile into 11380
bytes of shared object (when stripped).

import cython

cdef extern from "dirent.h":
    struct dirent:
        char d_name[0]
    ctypedef struct DIR
    DIR *opendir(char *name)
    int closedir(DIR *dirp)
    dirent *readdir(DIR *dirp)

cdef extern from "errno.h":
    int errno

cdef extern from "string.h":
    char *strerror(int errnum)

cdef class Directory:
    """Represents an open directory"""

    cdef DIR *handle

    def __init__(self, path):
        self.handle = opendir(path)
        if self.handle is NULL:
            raise OSError(errno, "Failed to open directory: %s" % strerror(errno))

    def readdir(self):
        """Read the next name in the directory"""
        cdef dirent *p
        p = readdir(self.handle)
        if p is NULL:
            return None
        return p.d_name

    def close(self):
        """Close the directory"""
        if self.handle is not NULL:
            closedir(self.handle)
            self.handle = NULL

    def __dealloc__(self):
        self.close()


-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From lodmod.dod at gmail.com  Fri Jul 17 14:32:50 2009
From: lodmod.dod at gmail.com (LoD MoD)
Date: Fri, 17 Jul 2009 11:32:50 -0700
Subject: getopt code NameError exception on logTail.py
In-Reply-To: <4A60BE10.5050905@mrabarnett.plus.com>
References: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>
	<4A60BE10.5050905@mrabarnett.plus.com>
Message-ID: <e8075cdd0907171132m361906fbw97dd20a58c930743@mail.gmail.com>

In this instance the trackback was somewhat unhelpful.There problem was
here:

           file = open(filename, 'r')

should be

           file = open(a, 'r')

args should be passed within the getopt riff

On Fri, Jul 17, 2009 at 11:08 AM, MRAB <python at mrabarnett.plus.com> wrote:

> LoD MoD wrote:
>
>> I am having trouble extending my option parsing.
>> Any help is appreciated:
>>
>> import sys
>> import getopt
>> import time
>>
>> def tail(file):
>>    while 1:
>>        where = file.tell()
>>        line = file.readline()
>>        if not line:
>>            time.sleep(1)
>>            file.seek(where)
>>        else:
>>            print line, # already has newline
>>
>> def main():
>>
>>    # parse command line options
>>    try:
>>        opts, args = getopt.getopt(sys.argv[1:], "hf:", ["help",
>> "filename="])
>>    except getopt.error, msg:
>>        print msg
>>        print "for help use --help"
>>        sys.exit(2)
>>    # process options
>>    for o, a in opts:
>>        if o in ("-h", "--help"):
>>            print __doc__
>>            sys.exit(0)
>>        if o in ("-f", "--filename"):
>>            print "Parsing F argument"
>>            file = open(filename, 'r')
>>            print file
>>
>>                        # process arguments
>>    for arg in args:
>>        process(arg) # process() is defined elsewhere
>>
>> if __name__ == "__main__":
>>    main()
>>
>> Yields this error:
>>
>> localhost:src gsery$ python logTail.py  /var/log/system.log
>> Traceback (most recent call last):
>>  File "logTail.py", line 52, in <module>
>>    main()
>>  File "logTail.py", line 49, in main
>>    process(arg) # process() is defined elsewhere
>> NameError: global name 'process' is not defined
>>
>>  The trackback tells you what's wrong: you haven't defined 'process'. The
> comment says it's defined elsewhere, but neither I nor Python can see
> it! :-)
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/644d3ab1/attachment-0001.html>

From phily05 at gmail.com  Fri Jul 17 14:42:28 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 11:42:28 -0700 (PDT)
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
	<mailman.3300.1247853630.8015.python-list@python.org>
Message-ID: <663ab878-2ba2-45f1-a38e-2cff94a6bb00@k30g2000yqf.googlegroups.com>

Thanks to both of you for the fast and detailed responses. I will just
treat the package for what it is, a namespace.


From phily05 at gmail.com  Fri Jul 17 14:43:49 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 11:43:49 -0700 (PDT)
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
	<mailman.3300.1247853630.8015.python-list@python.org>
Message-ID: <698e45d2-204b-46c0-ab80-8023e4b8ff15@y19g2000yqy.googlegroups.com>

Thanks to both of you for the fast and detailed responses. I will
just
use the package for what it is, a namespace.


From phily05 at gmail.com  Fri Jul 17 14:44:42 2009
From: phily05 at gmail.com (Phil)
Date: Fri, 17 Jul 2009 11:44:42 -0700 (PDT)
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
	<mailman.3300.1247853630.8015.python-list@python.org>
Message-ID: <9314b787-558b-4891-b519-23228c6d8fb7@m11g2000yqh.googlegroups.com>

Thanks to both of you for the fast and detailed responses. I will just
use the package for what it is, a namespace.


From python at mrabarnett.plus.com  Fri Jul 17 14:49:32 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 19:49:32 +0100
Subject: Generator Expressions and CSV
In-Reply-To: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
Message-ID: <4A60C7BC.4080904@mrabarnett.plus.com>

Zaki wrote:
> Hey all,
> 
> I'm really new to Python and this may seem like a really dumb
> question, but basically, I wrote a script to do the following, however
> the processing time/memory usage is not what I'd like it to be. Any
> suggestions?
> 
> 
> Outline:
> 1. Read tab delim files from a directory, files are of 3 types:
> install, update, and q. All 3 types contain ID values that are the
> only part of interest.
> 2. Using set() and set.add(), generate a list of unique IDs from
> install and update files.
> 3. Using the set created in (2), check the q files to see if there are
> matches for IDs. Keep all matches, and add any non matches (which only
> occur once in the q file) to a queue of lines to be removed from teh q
> files.
> 4. Remove the lines in the q for each file. (I haven't quite written
> the code for this, but I was going to implement this using csv.writer
> and rewriting all the lines in the file except for the ones in the
> removal queue).
> 
> Now, I've tried running this and it takes much longer than I'd like. I
> was wondering if there might be a better way to do things (I thought
> generator expressions might be a good way to attack this problem, as
> you could generate the set, and then check to see if there's a match,
> and write each line that way).
> 
Why are you checking and removing lines in 2 steps? Why not copy the
matching lines to a new q file and then replace the old file with the
new one (or, maybe, delete the new q file if no lines were removed)?


From smolds at comcast.net  Fri Jul 17 14:51:11 2009
From: smolds at comcast.net (Stephen M. Olds)
Date: Fri, 17 Jul 2009 11:51:11 -0700
Subject: Mechanize not recognized by py2exe
Message-ID: <4A60C81F.7080707@comcast.net>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/3b4715cc/attachment-0001.html>

From duncan.booth at invalid.invalid  Fri Jul 17 15:49:54 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 17 Jul 2009 19:49:54 GMT
Subject: ctype performance benchmark
References: <2b1ec74d-4e47-4eec-b128-bb00431ea651@y10g2000prg.googlegroups.com>
	<4a6037ea$0$31869$9b4e6d93@newsspool3.arcor-online.net>
	<48c15bac-8af2-472d-9bc0-1f19c4bf29cb@g7g2000prg.googlegroups.com>
Message-ID: <Xns9C4BD3E714F90duncanbooth@127.0.0.1>

Wai Yip <aurora00 at gmail.com> wrote:

> I started with ctypes because it is the battery included with the
> Python standard library. My code is very fluid and I'm looking for
> easy opportunity to optimize it. One example is to find the longest
> common prefix among two strings. Right now I am comparing it character
> by character with pure Python. It seems like an ideal low hanging
> fruit. With ctype I can rewriting a few lines of Python into a few
> lines of C. All the tools are available and no third party library is
> needed.

Alternatively you could just use os.path.commonprefix().



From travis+ml-python at subspacefield.org  Fri Jul 17 16:01:41 2009
From: travis+ml-python at subspacefield.org (travis+ml-python at subspacefield.org)
Date: Fri, 17 Jul 2009 15:01:41 -0500
Subject: proposal: add setresuid() system call to python
Message-ID: <20090717200141.GI6065@subspacefield.org>

Hello,

Historically, I have used scripting languages like python for typical
uses, but they tend to not fare very well at system programming; for
close interfacing with the operating system, I'm often forced to use a
language like C.  This is undesirable to me.

I do not think this has to be the case; I see no reason why a
scripting language can't implement more of the system call API, at the
risk of having some OS-dependent modules.  I would actually like to
see more network servers written in scripting languages, as they
neatly avoid buffer overflow and integer overflow issues with no extra
effort.

One BIG roadblock to doing this is when they can't manage to drop
permissions properly.

I am suggesting that the setresuid function be added to python,
perhaps in the OS module, because it has the clearest semantics for
manipulating user ids.  The reason why is best described in the
following paper:

http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf

One argument against this is that it is not specified by POSIX, and
thus might be dismissed as "implementation dependent".

However, as the paper above demonstrates, even though the setuid
system call is defined by POSIX, it already has system-dependent
behavior.  POSIX provides for at least two different behaviors of the
setuid call, and even more if you consider that it leaves what
constitutes "appropriate privileges" up to the OS kernel.

I humbly propose that python implement all the routines necessary to
securely drop privileges, to enable construction of network daemons
that might need to drop privileges from root to some non-root userid
(e.g. mail transfer agents, or POP/IMAP servers).

Furthermore, where there are multiple system calls to achieve this
effect, it should implement the ones with the clearest semantics, and
setresuid fits that bill.  To see what an utter mess the uid-manipulation
routines are in, I refer you once again to this paper, as the situation
is too complicated to describe in this email:

http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf

Opinions?

Best,
Travis
-- 
Obama Nation | My emails do not have attachments; it's a digital signature
that your mail program doesn't understand. | http://www.subspacefield.org/~travis/ 
If you are a spammer, please email john at subspacefield.org to get blacklisted.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 850 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/2a18ffb1/attachment-0001.sig>

From zaki.rahaman at gmail.com  Fri Jul 17 16:08:05 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 13:08:05 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
Message-ID: <71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>

On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Zaki wrote:
> > Hey all,
>
> > I'm really new to Python and this may seem like a really dumb
> > question, but basically, I wrote a script to do the following, however
> > the processing time/memory usage is not what I'd like it to be. Any
> > suggestions?
>
> > Outline:
> > 1. Read tab delim files from a directory, files are of 3 types:
> > install, update, and q. All 3 types contain ID values that are the
> > only part of interest.
> > 2. Using set() and set.add(), generate a list of unique IDs from
> > install and update files.
> > 3. Using the set created in (2), check the q files to see if there are
> > matches for IDs. Keep all matches, and add any non matches (which only
> > occur once in the q file) to a queue of lines to be removed from teh q
> > files.
> > 4. Remove the lines in the q for each file. (I haven't quite written
> > the code for this, but I was going to implement this using csv.writer
> > and rewriting all the lines in the file except for the ones in the
> > removal queue).
>
> > Now, I've tried running this and it takes much longer than I'd like. I
> > was wondering if there might be a better way to do things (I thought
> > generator expressions might be a good way to attack this problem, as
> > you could generate the set, and then check to see if there's a match,
> > and write each line that way).
>
> Why are you checking and removing lines in 2 steps? Why not copy the
> matching lines to a new q file and then replace the old file with the
> new one (or, maybe, delete the new q file if no lines were removed)?

That's what I've done now.

Here is the final code that I have running. It's very much 'hack' type
code and not at all efficient or optimized and any help in optimizing
it would be greatly appreciated.

import csv
import sys
import os
import time

begin = time.time()

#Check minutes elapsed
def timeElapsed():
    current = time.time()
    elapsed = current-begin
    return round(elapsed/60)


#USAGE: python logcleaner.py <input_dir> <output_dir>

inputdir = sys.argv[1]
outputdir = sys.argv[2]

logfilenames = os.listdir(inputdir)



IDs = set() #IDs from update and install logs
foundOnceInQuery = set()
#foundTwiceInQuery = set()
#IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
Queue of IDs to remove from query logs (IDs found only once in query
logs)

#Generate Filename Queues For Install/Update Logs, Query Logs
iNuQ = []
queryQ = []

for filename in logfilenames:
    if filename.startswith("par1.install") or filename.startswith
("par1.update"):
        iNuQ.append(filename)
    elif filename.startswith("par1.query"):
        queryQ.append(filename)

totalfiles = len(iNuQ) + len(queryQ)
print "Total # of Files to be Processed:" , totalfiles
print "Install/Update Logs to be processed:" , len(iNuQ)
print "Query logs to be processed:" , len(queryQ)

#Process install/update queue to generate list of valid IDs
currentfile = 1
for file in iNuQ:
    print "Processing", currentfile, "install/update log out of", len
(iNuQ)
    print timeElapsed()
    reader = csv.reader(open(inputdir+file),delimiter = '\t')
    for row in reader:
        IDs.add(row[2])
    currentfile+=1

print "Finished processing install/update logs"
print "Unique IDs found:" , len(IDs)
print "Total Time Elapsed:", timeElapsed()

currentfile = 1
for file in queryQ:
    print "Processing", currentfile, "query log out of", len(queryQ)
    print timeElapsed()
    reader = csv.reader(open(inputdir+file), delimiter = '\t')
    outputfile = csv.writer(open(outputdir+file), 'w')
    for row in reader:
        if row[2] in IDs:
            ouputfile.writerow(row)
        else:
            if row[2] in foundOnceInQuery:
                foundOnceInQuery.remove(row[2])
                outputfile.writerow(row)
                #IDremovalQ.remove(row[2])
                #foundTwiceInQuery.add(row[2])

            else:
                foundOnceInQuery.add(row[2])
                #IDremovalQ.add(row[2])


    currentfile+=1

print "Finished processing query logs and writing new files"
print "# of Query log entries removed:" , len(foundOnceInQuery)
print "Total Time Elapsed:", timeElapsed()




From jcd at sdf.lonestar.org  Fri Jul 17 16:08:26 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Fri, 17 Jul 2009 16:08:26 -0400
Subject: A Bug By Any Other Name ...
In-Reply-To: <kmy21c.fd3@spenarnc.xs4all.nl>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
	<kmy21c.fd3@spenarnc.xs4all.nl>
Message-ID: <1247861306.6362.6.camel@aalcdl07>

On Fri, 2009-07-17 at 20:53 +0000, Albert van der Horst wrote:
> Because unlike in algol 68 in python whitespace is relevant,
> we could get by with requiring whitespace:
>         x= -q                       # okay
>         a<b and -a<c and -b < -d    # okay
>         8 ** -2                     # okay

This is actually quite thoroughly untrue.  In python, *indentation* is
significant.  Whitespace (internal to a line) is not.  You can even call
methods like this if you want:

>>> s = 'abc'
>>> s        .     upper()
ABC

Obviously, that's A Bad Idea(tm), but python's parser won't stop you.
The ++ operator gotcha is so minor that I can't remember anyone actually
asking about it on the list (who was actually facing it as a
problem--this thread was started by idle speculation).  Can we not
change the language syntax to address non-issues?

Practicality beats purity, a.k.a. don't you have something better to do?


Cheers,
Cliff





From mabdelkader at gmail.com  Fri Jul 17 16:15:00 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Fri, 17 Jul 2009 16:15:00 -0400
Subject: proposal: add setresuid() system call to python
In-Reply-To: <20090717200141.GI6065@subspacefield.org>
References: <20090717200141.GI6065@subspacefield.org>
Message-ID: <148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>

Why don't you write a python extension module? This is a perfect opportunity
for that.

--
mahmoud mack abdelkader
http://blog.mahmoudimus.com/



On Fri, Jul 17, 2009 at 4:01 PM,
<travis+ml-python at subspacefield.org<travis%2Bml-python at subspacefield.org>
> wrote:

> Hello,
>
> Historically, I have used scripting languages like python for typical
> uses, but they tend to not fare very well at system programming; for
> close interfacing with the operating system, I'm often forced to use a
> language like C.  This is undesirable to me.
>
> I do not think this has to be the case; I see no reason why a
> scripting language can't implement more of the system call API, at the
> risk of having some OS-dependent modules.  I would actually like to
> see more network servers written in scripting languages, as they
> neatly avoid buffer overflow and integer overflow issues with no extra
> effort.
>
> One BIG roadblock to doing this is when they can't manage to drop
> permissions properly.
>
> I am suggesting that the setresuid function be added to python,
> perhaps in the OS module, because it has the clearest semantics for
> manipulating user ids.  The reason why is best described in the
> following paper:
>
> http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf<http://www.eecs.berkeley.edu/%7Edaw/papers/setuid-usenix02.pdf>
>
> One argument against this is that it is not specified by POSIX, and
> thus might be dismissed as "implementation dependent".
>
> However, as the paper above demonstrates, even though the setuid
> system call is defined by POSIX, it already has system-dependent
> behavior.  POSIX provides for at least two different behaviors of the
> setuid call, and even more if you consider that it leaves what
> constitutes "appropriate privileges" up to the OS kernel.
>
> I humbly propose that python implement all the routines necessary to
> securely drop privileges, to enable construction of network daemons
> that might need to drop privileges from root to some non-root userid
> (e.g. mail transfer agents, or POP/IMAP servers).
>
> Furthermore, where there are multiple system calls to achieve this
> effect, it should implement the ones with the clearest semantics, and
> setresuid fits that bill.  To see what an utter mess the uid-manipulation
> routines are in, I refer you once again to this paper, as the situation
> is too complicated to describe in this email:
>
> http://www.eecs.berkeley.edu/~daw/papers/setuid-usenix02.pdf<http://www.eecs.berkeley.edu/%7Edaw/papers/setuid-usenix02.pdf>
>
> Opinions?
>
> Best,
> Travis
> --
> Obama Nation | My emails do not have attachments; it's a digital signature
> that your mail program doesn't understand. |
> http://www.subspacefield.org/~travis/<http://www.subspacefield.org/%7Etravis/>
> If you are a spammer, please email john at subspacefield.org to get
> blacklisted.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/176d6f43/attachment-0001.html>

From robert.kern at gmail.com  Fri Jul 17 16:15:35 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 17 Jul 2009 15:15:35 -0500
Subject: proposal: add setresuid() system call to python
In-Reply-To: <20090717200141.GI6065@subspacefield.org>
References: <20090717200141.GI6065@subspacefield.org>
Message-ID: <h3qm59$guh$1@ger.gmane.org>

On 2009-07-17 15:01, travis+ml-python at subspacefield.org wrote:
> Hello,
>
> Historically, I have used scripting languages like python for typical
> uses, but they tend to not fare very well at system programming; for
> close interfacing with the operating system, I'm often forced to use a
> language like C.  This is undesirable to me.

You can use ctypes for most of these use cases.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From tjreedy at udel.edu  Fri Jul 17 16:32:51 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 16:32:51 -0400
Subject: turtle dump
In-Reply-To: <h3p5mm$o6s$01$1@news.t-online.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>	<h3o6hr$mmh$02$1@news.t-online.com>
	<h3obqg$aru$1@ger.gmane.org>	<mailman.3246.1247792169.8015.python-list@python.org>
	<h3p5mm$o6s$01$1@news.t-online.com>
Message-ID: <h3qn5k$jot$1@ger.gmane.org>

Peter Otten wrote:
> Terry Reedy wrote:
>
>> I tried it. Unfortunately, OOo does not open it correctly. It just
>> displays the first three lines of metadate - Title, Creator, Date -- as
>> image text. Photoshop does read the image, and does an ok job of
>> conversion once anti-aliasing is turned off.
> 
> I snatched some code from the module and modified it to save a sample image:

Thank you for the example.

> 
> from turtle import *
> 
> def switchpen():
>     if isdown():
>         pu()
>     else:
>         pd()
> 
> def demo2():
>     """Demo of some new features."""
>     speed(1)
>     st()
>     pensize(3)
>     setheading(towards(0, 0))
>     radius = distance(0, 0)/2.0
>     rt(90)
>     for _ in range(18):
>         switchpen()
>         circle(radius, 10)
>     write("wait a moment...")
>     while undobufferentries():
>         undo()
>     reset()
>     lt(90)
>     colormode(255)
>     laenge = 10
>     pencolor("green")
>     pensize(3)
>     lt(180)
>     for i in range(-2, 16):
>         if i > 0:
>             begin_fill()
>             fillcolor(255-15*i, 0, 15*i)
>         for _ in range(3):
>             fd(laenge)
>             lt(120)
>         laenge += 10
>         lt(15)
>         speed((speed()+1)%12)
>     end_fill()
> 
>     lt(120)
>     pu()
>     fd(70)
>     rt(30)
>     pd()
>     color("red","yellow")
>     speed(0)
>     fill(1)

begin_fill() in 3.x

>     for _ in range(4):
>         circle(50, 90)
>         rt(90)
>         fd(30)
>         rt(90)
>     fill(0)

end_fill() in 3.x

>     lt(90)
>     pu()
>     fd(30)
>     pd()
>     shape("turtle")
> 
>     tri = getturtle()
>     tri.resizemode("auto")
>     turtle = Turtle()
>     turtle.resizemode("auto")
>     turtle.shape("turtle")
>     turtle.reset()
>     turtle.left(90)
>     turtle.speed(0)
>     turtle.up()
>     turtle.goto(280, 40)
>     turtle.lt(30)
>     turtle.down()
>     turtle.speed(6)
>     turtle.color("blue","orange")
>     turtle.pensize(2)
>     tri.speed(6)
>     setheading(towards(turtle))
>     count = 1
>     while tri.distance(turtle) > 4:
>         turtle.fd(3.5)
>         turtle.lt(0.6)
>         tri.setheading(tri.towards(turtle))
>         tri.fd(4)
>         if count % 20 == 0:
>             turtle.stamp()
>             tri.stamp()
>             switchpen()
>         count += 1
>     tri.write("CAUGHT! ", font=("Arial", 16, "bold"), align="right")
> 
> if __name__ == "__main__":
>     demo2()
>     Screen().getcanvas().postscript(file="demo2.eps")
> 
> I could successfully insert the picture into Writer.

Whereas I still get just three lines of metadata.
The size of my demo2.eps is given as 65,628 bytes.
'Size on disk is given as a bit more but I presume that counts to the 
end of the last 4k block.

> I'm on Kubuntu 9.04 with Python 2.6.2 and OpenOffice 3.0.1.

WinXP with updates, Python 3.1, and OO 3.1.0

So either tk 8.5(?) on windows is producing something different or OO3.1 
  on windows is reading differently. If your file size is different, 
could you email it so I could try to import it here?

> But still, turtle is an educational tool, its main advantage is that it can 
> show beginners how the image is generated.

It is also available with Python as installed. And I want to do simple 
animations (of algoritms) as well as static pictures.

> If you want to generate high-quality graphics easily you need different 
> primitives.
> 
> http://cairographics.org
> 
> has Python bindings, but I don't know if it's available on Windows.

Effectively not, as far as I can tell. PyCairo appears to be *nix and 
require later binaries than those available from gtk site referenced 
from cairo site.

Terry Jan Reedy



From tjreedy at udel.edu  Fri Jul 17 16:36:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 16:36:17 -0400
Subject: turtle dump
In-Reply-To: <364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com>	<mailman.3245.1247785636.8015.python-list@python.org>
	<364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>
Message-ID: <h3qnc2$kb0$1@ger.gmane.org>

alex23 wrote:

> The help in iPython says the same, but also mentions that it's a
> dynamically generated function, so it may not be picking up the
> docstring that way. turtle.ScrolledCanvas.postscript is similarly
> terse, but you can find more info in turtle.Canvas.postscript:
> 
>   Print the contents of the canvas to a postscript
>   file. Valid options: colormap, colormode, file, fontmap,
>   height, pageanchor, pageheight, pagewidth, pagex, pagey,
>   rotate, witdh, x, y.

How, exactly, did you get that list?

tjr



From piet at cs.uu.nl  Fri Jul 17 16:48:37 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 22:48:37 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
	<mailman.3261.1247811927.8015.python-list@python.org>
	<m2eisfu2m0.fsf@cs.uu.nl>
	<mailman.3285.1247843986.8015.python-list@python.org>
Message-ID: <m2ws67rq6y.fsf@cs.uu.nl>

>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:

>GR> Piet van Oostrum wrote:
>>>>>>>> Gabriel Rossetti <gabriel.rossetti at arimaz.com> (GR) wrote:
>>>>>>>> 
>>> 
>>> 
>GR> I have a 1-1 relation, I have a thread reading msgs from a network socket
>GR> and a method waiting for an answer to arrive (see my thread
>GR> "Threading.Condition problem"). I would like to be able to have a timeout
>GR> as to not block forever, so the idea is to check if I returned because of a
>GR> timeout or not.
>>>> 
>>> 
>>> So that case is easy I think. After the wait just check if the answer
>>> has arrived.
>>> 
>GR> The problem is other answers could arrive that are not the one I
>GR> want. Maybe I could check if I got the answer, if not then check
>GR> how much time has elapsed, and if it's grater or equal to the
>GR> timeout consider it a timeout. I still think a return value would
>GR> be better though.

The wait will not get a return value in Python. There was an issue
posted in the tracker to request this in 2005. Recently (after 4 years)
it was rejected by the BDFL. See http://bugs.python.org/issue1175933

OK, your use case might be a bit more difficult, but I still think it
can be solved without a return value. I can't tell exactly how because
of lack of information.

So (as I already mentioned in one of my previous messages) being
notified doesn't imply that everything is OK. Now suppose that your CV
is notified one microsecond before it would time out but the required
answer did not arrive. What's the difference with a real timeout except
for that microsecond?

Reimplementing Condition yourself is not to be recommended I think.
Using these synchronisation primitives is hard enough let alone
implementing them. 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From albert at spenarnc.xs4all.nl  Fri Jul 17 16:53:36 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 17 Jul 2009 20:53:36 GMT
Subject: A Bug By Any Other Name ...
References: <h2rnoe$26s$5@lust.ihug.co.nz>
	<006d4a50$0$9711$c3e8da3@news.astraweb.com>
	<mailman.2664.1246857607.8015.python-list@python.org>
Message-ID: <kmy21c.fd3@spenarnc.xs4all.nl>

In article <mailman.2664.1246857607.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>En Mon, 06 Jul 2009 00:28:43 -0300, Steven D'Aprano
><steve at remove-this-cybersource.com.au> escribi?:
>> On Mon, 06 Jul 2009 14:32:46 +1200, Lawrence D'Oliveiro wrote:
>>
>>> I wonder how many people have been tripped up by the fact that
>>>
>>>     ++n
>>>
>>> and
>>>
>>>     --n
>>>
>>> fail silently for numeric-valued n.
>>
>> What do you mean, "fail silently"? They do exactly what you should
>> expect:
>>>>> ++5  # positive of a positive number is positive
>>
>> I'm not sure what "bug" you're seeing. Perhaps it's your expectations
>> that are buggy, not Python.
>
>Well, those expectations are taken seriously when new features are
>introduced into the language - and sometimes the feature is dismissed just
>because it would be confusing for some.
>If a += 1 works, expecting ++a to have the same meaning is very reasonable
>(for those coming from languages with a ++ operator, like C or Java) -
>more when ++a is a perfectly valid expression.
>If this issue isn't listed under the various "Python gotchas" articles, it
>should...

In algol 68 there was one thing strictly forbidden: putting two
operators behind each other:
x :=  y** -b .comment  must be x := y**(-b) .comment

This is quite a sensible rule, especially when, like in Python,
two special characters can be run together to denote a different
operator.
Examples abound :   +:=  **
A consequence is that  'a*-b'
would be illegal. It would become 'a*(-b)'
Worse is that x=-q would be illegal.

Because unlike in algol 68 in python whitespace is relevant,
we could get by with requiring whitespace:
        x= -q                       # okay
        a<b and -a<c and -b < -d    # okay
        8 ** -2                     # okay

Once a c-addict is forced to write
   + +a
she will realize that probably the operator is + is applied to
+a, and that a ++ has no meaning.

>--
>Gabriel Genellina

Groetjes Albert


--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From clp2 at rebertia.com  Fri Jul 17 16:55:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 17 Jul 2009 13:55:20 -0700
Subject: Writing a single list of numbers to a .m (matlab) file
In-Reply-To: <564970db0907171106q2be0852dg7209a4177f0b265a@mail.gmail.com>
References: <564970db0907171106q2be0852dg7209a4177f0b265a@mail.gmail.com>
Message-ID: <50697b2c0907171355q76f7c538le319b2240bb4210e@mail.gmail.com>

On Fri, Jul 17, 2009 at 11:06 AM, Hanna Michelsen<hannarosie at gmail.com> wrote:
> Hi,
>
> I was wondering if I could get some suggestions on how to write a single
> list of numbers to a .m file (for matlab) so that I can create a matlab
> vector out of the list of numbers from my python program. I have been using
> a csv writer to create .m files from lists of lists, but I'm not sure how to
> write just a single list to the file. (if I use the same code I've been
> using, I get an error: csv.Error sequence expected)

You didn't provide any code, but since csv is probably overkill anyway:

m_file.write("[" + " ".join(str(num) for num in numbers) + "]\n")

Cheers,
Chris
-- 
http://blog.rebertia.com


From python at mrabarnett.plus.com  Fri Jul 17 16:57:46 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 21:57:46 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <1247861306.6362.6.camel@aalcdl07>
References: <h2rnoe$26s$5@lust.ihug.co.nz>	<006d4a50$0$9711$c3e8da3@news.astraweb.com>	<mailman.2664.1246857607.8015.python-list@python.org>	<kmy21c.fd3@spenarnc.xs4all.nl>
	<1247861306.6362.6.camel@aalcdl07>
Message-ID: <4A60E5CA.1000106@mrabarnett.plus.com>

J. Cliff Dyer wrote:
> On Fri, 2009-07-17 at 20:53 +0000, Albert van der Horst wrote:
>> Because unlike in algol 68 in python whitespace is relevant,
>> we could get by with requiring whitespace:
>>         x= -q                       # okay
>>         a<b and -a<c and -b < -d    # okay
>>         8 ** -2                     # okay
> 
> This is actually quite thoroughly untrue.  In python, *indentation* is
> significant.  Whitespace (internal to a line) is not.
[snip]
Whitespace (internal to a line) _mostly_ is not. It's not allowed within
names, and it is needed in the second example above, before the 'and's.


From exarkun at divmod.com  Fri Jul 17 16:59:53 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Fri, 17 Jul 2009 16:59:53 -0400
Subject: proposal: add setresuid() system call to python
In-Reply-To: <20090717200141.GI6065@subspacefield.org>
Message-ID: <20090717205953.2543.1223422516.divmod.quotient.3129@henry.divmod.com>

On Fri, 17 Jul 2009 15:01:41 -0500, travis+ml-python at subspacefield.org wrote:
>Hello,
>
> [snip]
>
>I am suggesting that the setresuid function be added to python,
>perhaps in the OS module, because it has the clearest semantics for
>manipulating user ids.  The reason why is best described in the
>following paper:

Yes, it'd be good for Python to expose setresuid.  The best course of
action is to file a ticket in the issue tracker.  Things will be sped
along if you also attach a patch implementing the change. :)

Jean-Paul


From piet at cs.uu.nl  Fri Jul 17 16:59:54 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 17 Jul 2009 22:59:54 +0200
Subject: no return value for threading.Condition.wait(timeout)?
References: <mailman.3221.1247757153.8015.python-list@python.org>
	<m21voguvxz.fsf@cs.uu.nl>
	<mailman.3261.1247811927.8015.python-list@python.org>
	<m2eisfu2m0.fsf@cs.uu.nl>
	<mailman.3285.1247843986.8015.python-list@python.org>
	<m2ws67rq6y.fsf@cs.uu.nl>
Message-ID: <m2skgvrpo5.fsf@cs.uu.nl>

I should add that *if the wait times out* it still could be the case
that your answer has arrived but that the notify occured a microsecond
after the timeout. So knowing if the timeout occurred really doesn't
tell you much. It's just a way to prevent infinite waiting.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From tjreedy at udel.edu  Fri Jul 17 16:59:59 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 16:59:59 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <SfY7m.5466$875.1940@newsfe20.ams2>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
Message-ID: <h3qoof$n9v$1@ger.gmane.org>

Sion Arrowsmith wrote:
> Jack Diederich  <jackdied at gmail.com> wrote:
>> It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>> dicts also raise an error if you try to LT them.
> 
> Since when?
> 
> Python 2.5.2 (r252:60911, Jan  4 2009, 17:40:26)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> d1 = dict((str(i), i) for i in range (10))
>>>> d2 = dict((str(i), i) for i in range (20))
>>>> d1 < d2
> True

Try reversing the definitions of d1 and d2. The dicts are probably being 
compared by id (address), which is the 2.x CPython default.

> (Don't have a 2.6 or 3 to hand.)

2.6 same. 3.1
 >>> d1,d2 = {},{}
 >>> d1 < d2
Traceback (most recent call last):
   File "<pyshell#16>", line 1, in <module>
     d1 < d2
TypeError: unorderable types: dict() < dict()



From aahz at pythoncraft.com  Fri Jul 17 17:03:59 2009
From: aahz at pythoncraft.com (Aahz)
Date: 17 Jul 2009 14:03:59 -0700
Subject: Passing python list from C to python
References: <68dd04fa-6f62-4cb9-807d-ec12d7216fd7@n4g2000vba.googlegroups.com>
	<0afc5c4d-1af5-4d0e-9442-26b51b12e5b4@m11g2000yqh.googlegroups.com>
	<h3nusa$pcb$1@panix3.panix.com>
	<94c1adf3-a25d-4ae5-9f38-7ca8680d022d@b14g2000yqd.googlegroups.com>
Message-ID: <h3qovv$ivk$1@panix3.panix.com>

In article <94c1adf3-a25d-4ae5-9f38-7ca8680d022d at b14g2000yqd.googlegroups.com>,
hartley  <hartley79 at gmail.com> wrote:
>On Jul 16, 9:26=A0pm, a... at pythoncraft.com (Aahz) wrote:
>> In article <0afc5c4d-1af5-4d0e-9442-26b51b12e... at m11g2000yqh.googlegroups=
>.com>,
>> hartley =A0<hartle... at gmail.com> wrote:
>>>
>>>If you had loosened up on the sarcasm I would probably have read what
>>>you wrote more thoroughly instead of just skimming through it. Thanks
>>>for the help, but you should seriously consider doing something with
>>>your patronizing attitude.
>>
>> http://www.mikeash.com/getting_answers.htmlhttp://www.catb.org/~esr/faqs/=
>smart-questions.html
>
>From "http://www.mikeash.com/getting_answers.html":
>
>How To Ask Questions The Smart Way is pretty condescending, especially
>if you already feel insulted by somebody telling you that you need
>help asking questions. If you're pointed at a guide with a filename of
>smart-questions, that means this person thinks you have stupid
>questions, and who needs that?
>
>Cheers mate :)

Not really.  Feel free to chide people trying to help you, eventually
people won't care.  <shrug>
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"If you think it's expensive to hire a professional to do the job, wait
until you hire an amateur."  --Red Adair


From tjreedy at udel.edu  Fri Jul 17 17:09:40 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 17 Jul 2009 17:09:40 -0400
Subject: 'del' function for Dictionary
In-Reply-To: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
References: <ff4d16090907170842l60bec88g902d6d6611cc0571@mail.gmail.com>
Message-ID: <h3qpal$psp$1@ger.gmane.org>

mayank gupta wrote:
> Hi all,
> 
> I wanted to know whether there is a more efficient way to delete an 
> entry from a dictionary (instead of using the 'del' function), because 
> after analyzing the time taken by the code, it seems to me that the 
> 'del' function takes most of the time.

That is hard to imagine.

del ob[sub]

has the same effect as

ob.__delitem__(sub)

but I suspect this would take longer since it requires a runtime 
attribute lookup and Python level function call.  So I am pretty sure 
the answer is 'no'.

tjr



From python at mrabarnett.plus.com  Fri Jul 17 17:31:30 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 17 Jul 2009 22:31:30 +0100
Subject: Generator Expressions and CSV
In-Reply-To: <71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
Message-ID: <4A60EDB2.5050202@mrabarnett.plus.com>

Zaki wrote:
> On Jul 17, 2:49 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> Zaki wrote:
>>> Hey all,
>>> I'm really new to Python and this may seem like a really dumb
>>> question, but basically, I wrote a script to do the following, however
>>> the processing time/memory usage is not what I'd like it to be. Any
>>> suggestions?
>>> Outline:
>>> 1. Read tab delim files from a directory, files are of 3 types:
>>> install, update, and q. All 3 types contain ID values that are the
>>> only part of interest.
>>> 2. Using set() and set.add(), generate a list of unique IDs from
>>> install and update files.
>>> 3. Using the set created in (2), check the q files to see if there are
>>> matches for IDs. Keep all matches, and add any non matches (which only
>>> occur once in the q file) to a queue of lines to be removed from teh q
>>> files.
>>> 4. Remove the lines in the q for each file. (I haven't quite written
>>> the code for this, but I was going to implement this using csv.writer
>>> and rewriting all the lines in the file except for the ones in the
>>> removal queue).
>>> Now, I've tried running this and it takes much longer than I'd like. I
>>> was wondering if there might be a better way to do things (I thought
>>> generator expressions might be a good way to attack this problem, as
>>> you could generate the set, and then check to see if there's a match,
>>> and write each line that way).
>> Why are you checking and removing lines in 2 steps? Why not copy the
>> matching lines to a new q file and then replace the old file with the
>> new one (or, maybe, delete the new q file if no lines were removed)?
> 
> That's what I've done now.
> 
> Here is the final code that I have running. It's very much 'hack' type
> code and not at all efficient or optimized and any help in optimizing
> it would be greatly appreciated.
> 
> import csv
> import sys
> import os
> import time
> 
> begin = time.time()
> 
> #Check minutes elapsed
> def timeElapsed():
>     current = time.time()
>     elapsed = current-begin
>     return round(elapsed/60)
> 
> 
> #USAGE: python logcleaner.py <input_dir> <output_dir>
> 
> inputdir = sys.argv[1]
> outputdir = sys.argv[2]
> 
> logfilenames = os.listdir(inputdir)
> 
> 
> 
> IDs = set() #IDs from update and install logs
> foundOnceInQuery = set()
> #foundTwiceInQuery = set()
> #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> Queue of IDs to remove from query logs (IDs found only once in query
> logs)
> 
> #Generate Filename Queues For Install/Update Logs, Query Logs
> iNuQ = []
> queryQ = []
> 
> for filename in logfilenames:
>     if filename.startswith("par1.install") or filename.startswith
> ("par1.update"):
      if filename.startswith(("par1.install", "par1.update")):

>         iNuQ.append(filename)
>     elif filename.startswith("par1.query"):
>         queryQ.append(filename)
> 
> totalfiles = len(iNuQ) + len(queryQ)
> print "Total # of Files to be Processed:" , totalfiles
> print "Install/Update Logs to be processed:" , len(iNuQ)
> print "Query logs to be processed:" , len(queryQ)
> 
> #Process install/update queue to generate list of valid IDs
> currentfile = 1
> for file in iNuQ:
 >     print "Processing", currentfile, "install/update log out of", len
 > (iNuQ)
 >     print timeElapsed()
 >     reader = csv.reader(open(inputdir+file),delimiter = '\t')
 >     for row in reader:
 >         IDs.add(row[2])
 >     currentfile+=1

Best not to call it 'file'; that's a built-in name.

Also you could use 'enumerate', and joining filepaths is safer with
os.path.join().

for currentfile, filename in enumerate(iNuQ, start=1):
     print "Processing", currentfile, "install/update log out of", len(iNuQ)
     print timeElapsed()
     current_path = os.path.join(inputdir, filename)
     reader = csv.reader(open(current_path), delimiter = '\t')
     for row in reader:
         IDs.add(row[2])

> 
> print "Finished processing install/update logs"
> print "Unique IDs found:" , len(IDs)
> print "Total Time Elapsed:", timeElapsed()
> 
> currentfile = 1
> for file in queryQ:

Similar remarks to above ...

>     print "Processing", currentfile, "query log out of", len(queryQ)
>     print timeElapsed()
>     reader = csv.reader(open(inputdir+file), delimiter = '\t')
>     outputfile = csv.writer(open(outputdir+file), 'w')

... and also here.

>     for row in reader:
>         if row[2] in IDs:
>             ouputfile.writerow(row)

Should be 'outputfile'.

>         else:
>             if row[2] in foundOnceInQuery:
>                 foundOnceInQuery.remove(row[2])

You're removing the ID here ...

>                 outputfile.writerow(row)
>                 #IDremovalQ.remove(row[2])
>                 #foundTwiceInQuery.add(row[2])
> 
>             else:
>                 foundOnceInQuery.add(row[2])

... and adding it again here!

>                 #IDremovalQ.add(row[2])
> 
> 
>     currentfile+=1
> 
For safety you should close the files after use.

> print "Finished processing query logs and writing new files"
> print "# of Query log entries removed:" , len(foundOnceInQuery)
> print "Total Time Elapsed:", timeElapsed()
> 
Apart from that, it looks OK.

How big are the q files? If they're not too big and most of the time
you're not removing rows, you could put the output rows into a list and
then create the output file only if rows have been removed, otherwise
just copy the input file, which might be faster.


From emile at fenx.com  Fri Jul 17 17:56:12 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 17 Jul 2009 14:56:12 -0700
Subject: Generator Expressions and CSV
In-Reply-To: <71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
Message-ID: <h3qrse$j2$1@ger.gmane.org>

On 7/17/2009 1:08 PM Zaki said...
> Here is the final code that I have running. It's very much 'hack' type
> code and not at all efficient or optimized and any help in optimizing
> it would be greatly appreciated.

There are some things I'd approach differently , eg I might prefer glob 
to build iNuQ and queryQ [1], and although glob is generally fast, I'm 
not sure it'd be faster.  But overall it looks like most of the time is 
spent in your 'for row in' loops, and as you're reading each file only 
once, and would have to anyway, there's not much that'll improve overall 
timing.  I don't know what csvreader is doing under the covers, but if 
your files are reasonably sized for your system you might try timing 
something that reads in the full file and splits:

for each in filelist:
     for row in open(filelist).readlines():
         if row.split()[2] in ....

-----[1]-----
import glob

iNuQ = glob.glob(os.sep.join(inputdir,"par1.install*")
queryQ = glob.glob(os.sep.join(inputdir,"par1.query*")



Emile



From lie.1296 at gmail.com  Fri Jul 17 17:58:21 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sat, 18 Jul 2009 07:58:21 +1000
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>	<mailman.3275.1247836630.8015.python-list@python.org>	<02707804$0$5185$c3e8da3@news.astraweb.com>	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
Message-ID: <h3qs5u$1cr$1@ger.gmane.org>

Xavier Ho wrote:
> oops, wrong address.
> 
> When will reply-to tag appear on the Python mailing list? =/
> 
> Good idea, Steven and MRAB.
> 
> I changed my code to the following:
> 
> 
>     def nPrime(self, n):
>         "Returns nth prime number, the first one being 2, where n = 0.
> When n = 1, it returns 3."
>         for x in range(n+2):
> 
>             try:
>                 return self.primes[n]
>             except IndexError:
>                 self.next()

If you're looking for speed, you should be aware that a failed
try-clause is quite expensive in python and often (as in this case)
codes using exception can be less readable than the one without since a
program's flow in the case of exception is not linear (the non-linear
execution is useful for quickly breaking out from nests of clauses, but
not necessary in this case).

Semantically, it is also wrong. Not finding the n'th prime in the cache
is not really an exceptional case.

If you insists on using a try-except clause, use it this way:

# untested
def nPrime(self, n):
    try:
        return self.primes[n]
    except IndexError:
        for _ in xrange(len(self.primes), n+1):
            self.next()
        return self.primes[n]



From lodmod.dod at gmail.com  Fri Jul 17 17:58:46 2009
From: lodmod.dod at gmail.com (LoD MoD)
Date: Fri, 17 Jul 2009 14:58:46 -0700
Subject: creating my own logwatch in python
Message-ID: <e8075cdd0907171458g162db8aai9dc5ef6ba49ec886@mail.gmail.com>

I am trying to fabricate a logwatch-type script in Python and I'm having
some trouble.What happens with the following code is that it prints to the
screen but the if condition on line 22 never gets executed.

http://pastie.org/549975

Any suggestions are appreciated.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/5f8757ba/attachment-0001.html>

From contact at xavierho.com  Fri Jul 17 18:07:13 2009
From: contact at xavierho.com (Xavier Ho)
Date: Sat, 18 Jul 2009 06:07:13 +0800
Subject: Try... except....Try again?
In-Reply-To: <h3qs5u$1cr$1@ger.gmane.org>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
	<h3qs5u$1cr$1@ger.gmane.org>
Message-ID: <2d56febf0907171507y75f6436ete75cb3f748ee838d@mail.gmail.com>

On Sat, Jul 18, 2009 at 5:58 AM, Lie Ryan <lie.1296 at gmail.com> wrote:

>
>
> If you're looking for speed, you should be aware that a failed
> try-clause is quite expensive in python and often (as in this case)
> codes using exception can be less readable than the one without since a
> program's flow in the case of exception is not linear (the non-linear
> execution is useful for quickly breaking out from nests of clauses, but
> not necessary in this case).


Was not aware that myself. Noted.


> Semantically, it is also wrong. Not finding the n'th prime in the cache
> is not really an exceptional case.
>
> If you insists on using a try-except clause, use it this way:
>
> Well, I don't have to use try-except. I think I got another idea though. I
could use an internal counter to keep track of how many prime numbers have
generated, and if not enough, generate more.

Thanks.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/9125440d/attachment-0001.html>

From mabdelkader at gmail.com  Fri Jul 17 18:33:55 2009
From: mabdelkader at gmail.com (Mahmoud Abdelkader)
Date: Fri, 17 Jul 2009 18:33:55 -0400
Subject: creating my own logwatch in python
In-Reply-To: <e8075cdd0907171458g162db8aai9dc5ef6ba49ec886@mail.gmail.com>
References: <e8075cdd0907171458g162db8aai9dc5ef6ba49ec886@mail.gmail.com>
Message-ID: <148918f0907171533y4044b171h54e91c142a21b6cf@mail.gmail.com>

A few code critiques:
 -  Your code is not very help friendly because it can not be run, so I have
to deadlist debug it.
 -  There are various syntax errors in the code:
    - for example: file is not defined when you invoke tail(file)
 -  You are overshadowing a built-in type 'file' by that name, which is
confusing. PEP 8 states that if you want to use a keyword, the practice is
to put an underscore after it. So, it should become file_
 -  Getopt is very old and should not be used. You should use the better,
readable, optparse
 -  That while loop will consume 99% CPU because of the infinite loop
 -  line = file.readline() is guaranteed to return a newline OR an empty
string ONLY when an EOF is encountered since you're not specifying the
optional maximum read byte size. This means that all your characters are
strings. So, why do you explicitly convert each character to a string and
separate each character by a space? (line 18)
 - Line 19 will always return 0 because of line 18
 - Line 19->22 are completely redundant, since readline is guaranteed to
give you ONE line. You should just do if "uccess" in logString: ...

Hope this helps,
mahmoud mack abdelkader
http://blog.mahmoudimus.com/



On Fri, Jul 17, 2009 at 5:58 PM, LoD MoD <lodmod.dod at gmail.com> wrote:

> I am trying to fabricate a logwatch-type script in Python and I'm having
> some trouble.What happens with the following code is that it prints to the
> screen but the if condition on line 22 never gets executed.
>
> http://pastie.org/549975
>
> Any suggestions are appreciated.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/084f8280/attachment-0001.html>

From zaki.rahaman at gmail.com  Fri Jul 17 18:39:33 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 15:39:33 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
	<mailman.3319.1247866273.8015.python-list@python.org>
Message-ID: <1e8faacc-f4bc-420a-8028-88e405abb81f@d4g2000yqa.googlegroups.com>

On Jul 17, 5:31?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Zaki wrote:
> > On Jul 17, 2:49 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> >> Zaki wrote:
> >>> Hey all,
> >>> I'm really new to Python and this may seem like a really dumb
> >>> question, but basically, I wrote a script to do the following, however
> >>> the processing time/memory usage is not what I'd like it to be. Any
> >>> suggestions?
> >>> Outline:
> >>> 1. Read tab delim files from a directory, files are of 3 types:
> >>> install, update, and q. All 3 types contain ID values that are the
> >>> only part of interest.
> >>> 2. Using set() and set.add(), generate a list of unique IDs from
> >>> install and update files.
> >>> 3. Using the set created in (2), check the q files to see if there are
> >>> matches for IDs. Keep all matches, and add any non matches (which only
> >>> occur once in the q file) to a queue of lines to be removed from teh q
> >>> files.
> >>> 4. Remove the lines in the q for each file. (I haven't quite written
> >>> the code for this, but I was going to implement this using csv.writer
> >>> and rewriting all the lines in the file except for the ones in the
> >>> removal queue).
> >>> Now, I've tried running this and it takes much longer than I'd like. I
> >>> was wondering if there might be a better way to do things (I thought
> >>> generator expressions might be a good way to attack this problem, as
> >>> you could generate the set, and then check to see if there's a match,
> >>> and write each line that way).
> >> Why are you checking and removing lines in 2 steps? Why not copy the
> >> matching lines to a new q file and then replace the old file with the
> >> new one (or, maybe, delete the new q file if no lines were removed)?
>
> > That's what I've done now.
>
> > Here is the final code that I have running. It's very much 'hack' type
> > code and not at all efficient or optimized and any help in optimizing
> > it would be greatly appreciated.
>
> > import csv
> > import sys
> > import os
> > import time
>
> > begin = time.time()
>
> > #Check minutes elapsed
> > def timeElapsed():
> > ? ? current = time.time()
> > ? ? elapsed = current-begin
> > ? ? return round(elapsed/60)
>
> > #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> > inputdir = sys.argv[1]
> > outputdir = sys.argv[2]
>
> > logfilenames = os.listdir(inputdir)
>
> > IDs = set() #IDs from update and install logs
> > foundOnceInQuery = set()
> > #foundTwiceInQuery = set()
> > #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> > Queue of IDs to remove from query logs (IDs found only once in query
> > logs)
>
> > #Generate Filename Queues For Install/Update Logs, Query Logs
> > iNuQ = []
> > queryQ = []
>
> > for filename in logfilenames:
> > ? ? if filename.startswith("par1.install") or filename.startswith
> > ("par1.update"):
>
> ? ? ? if filename.startswith(("par1.install", "par1.update")):
>
> > ? ? ? ? iNuQ.append(filename)
> > ? ? elif filename.startswith("par1.query"):
> > ? ? ? ? queryQ.append(filename)
>
> > totalfiles = len(iNuQ) + len(queryQ)
> > print "Total # of Files to be Processed:" , totalfiles
> > print "Install/Update Logs to be processed:" , len(iNuQ)
> > print "Query logs to be processed:" , len(queryQ)
>
> > #Process install/update queue to generate list of valid IDs
> > currentfile = 1
> > for file in iNuQ:
>
> ?> ? ? print "Processing", currentfile, "install/update log out of", len
> ?> (iNuQ)
> ?> ? ? print timeElapsed()
> ?> ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> ?> ? ? for row in reader:
> ?> ? ? ? ? IDs.add(row[2])
> ?> ? ? currentfile+=1
>
> Best not to call it 'file'; that's a built-in name.
>
> Also you could use 'enumerate', and joining filepaths is safer with
> os.path.join().
>
> for currentfile, filename in enumerate(iNuQ, start=1):
> ? ? ?print "Processing", currentfile, "install/update log out of", len(iNuQ)
> ? ? ?print timeElapsed()
> ? ? ?current_path = os.path.join(inputdir, filename)
> ? ? ?reader = csv.reader(open(current_path), delimiter = '\t')
> ? ? ?for row in reader:
> ? ? ? ? ?IDs.add(row[2])
>
>
>
> > print "Finished processing install/update logs"
> > print "Unique IDs found:" , len(IDs)
> > print "Total Time Elapsed:", timeElapsed()
>
> > currentfile = 1
> > for file in queryQ:
>
> Similar remarks to above ...
>
> > ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> > ? ? print timeElapsed()
> > ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> > ? ? outputfile = csv.writer(open(outputdir+file), 'w')
>
> ... and also here.
>
> > ? ? for row in reader:
> > ? ? ? ? if row[2] in IDs:
> > ? ? ? ? ? ? ouputfile.writerow(row)
>
> Should be 'outputfile'.
>
> > ? ? ? ? else:
> > ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
>
> You're removing the ID here ...
>
> > ? ? ? ? ? ? ? ? outputfile.writerow(row)
> > ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> > ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> > ? ? ? ? ? ? else:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
>
> ... and adding it again here!
>
> > ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> > ? ? currentfile+=1
>
> For safety you should close the files after use.
>
> > print "Finished processing query logs and writing new files"
> > print "# of Query log entries removed:" , len(foundOnceInQuery)
> > print "Total Time Elapsed:", timeElapsed()
>
> Apart from that, it looks OK.
>
> How big are the q files? If they're not too big and most of the time
> you're not removing rows, you could put the output rows into a list and
> then create the output file only if rows have been removed, otherwise
> just copy the input file, which might be faster.

MRAB, could you please repost what I sent to you here as I meant to
post it in the main discussion.


From joncle at googlemail.com  Fri Jul 17 18:40:27 2009
From: joncle at googlemail.com (Jon Clements)
Date: Fri, 17 Jul 2009 15:40:27 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
Message-ID: <51ce01d3-4620-4e5f-b5b5-bd0e9fd6fd2c@w41g2000yqb.googlegroups.com>

On 17 July, 21:08, Zaki <zaki.raha... at gmail.com> wrote:
> On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
>
>
> > Zaki wrote:
> > > Hey all,
>
> > > I'm really new to Python and this may seem like a really dumb
> > > question, but basically, I wrote a script to do the following, however
> > > the processing time/memory usage is not what I'd like it to be. Any
> > > suggestions?
>
> > > Outline:
> > > 1. Read tab delim files from a directory, files are of 3 types:
> > > install, update, and q. All 3 types contain ID values that are the
> > > only part of interest.
> > > 2. Using set() and set.add(), generate a list of unique IDs from
> > > install and update files.
> > > 3. Using the set created in (2), check the q files to see if there are
> > > matches for IDs. Keep all matches, and add any non matches (which only
> > > occur once in the q file) to a queue of lines to be removed from teh q
> > > files.
> > > 4. Remove the lines in the q for each file. (I haven't quite written
> > > the code for this, but I was going to implement this using csv.writer
> > > and rewriting all the lines in the file except for the ones in the
> > > removal queue).
>
> > > Now, I've tried running this and it takes much longer than I'd like. I
> > > was wondering if there might be a better way to do things (I thought
> > > generator expressions might be a good way to attack this problem, as
> > > you could generate the set, and then check to see if there's a match,
> > > and write each line that way).
>
> > Why are you checking and removing lines in 2 steps? Why not copy the
> > matching lines to a new q file and then replace the old file with the
> > new one (or, maybe, delete the new q file if no lines were removed)?
>
> That's what I've done now.
>
> Here is the final code that I have running. It's very much 'hack' type
> code and not at all efficient or optimized and any help in optimizing
> it would be greatly appreciated.
>
> import csv
> import sys
> import os
> import time
>
> begin = time.time()
>
> #Check minutes elapsed
> def timeElapsed():
> ? ? current = time.time()
> ? ? elapsed = current-begin
> ? ? return round(elapsed/60)
>
> #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> inputdir = sys.argv[1]
> outputdir = sys.argv[2]
>
> logfilenames = os.listdir(inputdir)
>
> IDs = set() #IDs from update and install logs
> foundOnceInQuery = set()
> #foundTwiceInQuery = set()
> #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> Queue of IDs to remove from query logs (IDs found only once in query
> logs)
>
> #Generate Filename Queues For Install/Update Logs, Query Logs
> iNuQ = []
> queryQ = []
>
> for filename in logfilenames:
> ? ? if filename.startswith("par1.install") or filename.startswith
> ("par1.update"):
> ? ? ? ? iNuQ.append(filename)
> ? ? elif filename.startswith("par1.query"):
> ? ? ? ? queryQ.append(filename)
>
> totalfiles = len(iNuQ) + len(queryQ)
> print "Total # of Files to be Processed:" , totalfiles
> print "Install/Update Logs to be processed:" , len(iNuQ)
> print "Query logs to be processed:" , len(queryQ)
>
> #Process install/update queue to generate list of valid IDs
> currentfile = 1
> for file in iNuQ:
> ? ? print "Processing", currentfile, "install/update log out of", len
> (iNuQ)
> ? ? print timeElapsed()
> ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> ? ? for row in reader:
> ? ? ? ? IDs.add(row[2])
> ? ? currentfile+=1
>
> print "Finished processing install/update logs"
> print "Unique IDs found:" , len(IDs)
> print "Total Time Elapsed:", timeElapsed()
>
> currentfile = 1
> for file in queryQ:
> ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> ? ? print timeElapsed()
> ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> ? ? outputfile = csv.writer(open(outputdir+file), 'w')
> ? ? for row in reader:
> ? ? ? ? if row[2] in IDs:
> ? ? ? ? ? ? ouputfile.writerow(row)
> ? ? ? ? else:
> ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
> ? ? ? ? ? ? ? ? outputfile.writerow(row)
> ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> ? ? ? ? ? ? else:
> ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
> ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> ? ? currentfile+=1
>
> print "Finished processing query logs and writing new files"
> print "# of Query log entries removed:" , len(foundOnceInQuery)
> print "Total Time Elapsed:", timeElapsed()

Just a couple of ideas:

1) load the data into a sqlite3 database and use an SQL query to
extract your results (has the potential of doing what you want without
you coding it, plus if your requirements change, maybe somewhat more
flexible)

2) Pre-sort your input files via ID, then match-merge (may add some
time/space required to sort, but then the merge should be fairly
quick, plus you'll have access to the entire row in the process, not
just the ID)

Jon.


From zaki.rahaman at gmail.com  Fri Jul 17 18:57:48 2009
From: zaki.rahaman at gmail.com (Zaki)
Date: Fri, 17 Jul 2009 15:57:48 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
	<51ce01d3-4620-4e5f-b5b5-bd0e9fd6fd2c@w41g2000yqb.googlegroups.com>
Message-ID: <8298385a-6f4b-44a5-b171-4871833f8dd2@c36g2000yqn.googlegroups.com>

On Jul 17, 6:40?pm, Jon Clements <jon... at googlemail.com> wrote:
> On 17 July, 21:08, Zaki <zaki.raha... at gmail.com> wrote:
>
>
>
> > On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > Zaki wrote:
> > > > Hey all,
>
> > > > I'm really new to Python and this may seem like a really dumb
> > > > question, but basically, I wrote a script to do the following, however
> > > > the processing time/memory usage is not what I'd like it to be. Any
> > > > suggestions?
>
> > > > Outline:
> > > > 1. Read tab delim files from a directory, files are of 3 types:
> > > > install, update, and q. All 3 types contain ID values that are the
> > > > only part of interest.
> > > > 2. Using set() and set.add(), generate a list of unique IDs from
> > > > install and update files.
> > > > 3. Using the set created in (2), check the q files to see if there are
> > > > matches for IDs. Keep all matches, and add any non matches (which only
> > > > occur once in the q file) to a queue of lines to be removed from teh q
> > > > files.
> > > > 4. Remove the lines in the q for each file. (I haven't quite written
> > > > the code for this, but I was going to implement this using csv.writer
> > > > and rewriting all the lines in the file except for the ones in the
> > > > removal queue).
>
> > > > Now, I've tried running this and it takes much longer than I'd like. I
> > > > was wondering if there might be a better way to do things (I thought
> > > > generator expressions might be a good way to attack this problem, as
> > > > you could generate the set, and then check to see if there's a match,
> > > > and write each line that way).
>
> > > Why are you checking and removing lines in 2 steps? Why not copy the
> > > matching lines to a new q file and then replace the old file with the
> > > new one (or, maybe, delete the new q file if no lines were removed)?
>
> > That's what I've done now.
>
> > Here is the final code that I have running. It's very much 'hack' type
> > code and not at all efficient or optimized and any help in optimizing
> > it would be greatly appreciated.
>
> > import csv
> > import sys
> > import os
> > import time
>
> > begin = time.time()
>
> > #Check minutes elapsed
> > def timeElapsed():
> > ? ? current = time.time()
> > ? ? elapsed = current-begin
> > ? ? return round(elapsed/60)
>
> > #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> > inputdir = sys.argv[1]
> > outputdir = sys.argv[2]
>
> > logfilenames = os.listdir(inputdir)
>
> > IDs = set() #IDs from update and install logs
> > foundOnceInQuery = set()
> > #foundTwiceInQuery = set()
> > #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> > Queue of IDs to remove from query logs (IDs found only once in query
> > logs)
>
> > #Generate Filename Queues For Install/Update Logs, Query Logs
> > iNuQ = []
> > queryQ = []
>
> > for filename in logfilenames:
> > ? ? if filename.startswith("par1.install") or filename.startswith
> > ("par1.update"):
> > ? ? ? ? iNuQ.append(filename)
> > ? ? elif filename.startswith("par1.query"):
> > ? ? ? ? queryQ.append(filename)
>
> > totalfiles = len(iNuQ) + len(queryQ)
> > print "Total # of Files to be Processed:" , totalfiles
> > print "Install/Update Logs to be processed:" , len(iNuQ)
> > print "Query logs to be processed:" , len(queryQ)
>
> > #Process install/update queue to generate list of valid IDs
> > currentfile = 1
> > for file in iNuQ:
> > ? ? print "Processing", currentfile, "install/update log out of", len
> > (iNuQ)
> > ? ? print timeElapsed()
> > ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> > ? ? for row in reader:
> > ? ? ? ? IDs.add(row[2])
> > ? ? currentfile+=1
>
> > print "Finished processing install/update logs"
> > print "Unique IDs found:" , len(IDs)
> > print "Total Time Elapsed:", timeElapsed()
>
> > currentfile = 1
> > for file in queryQ:
> > ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> > ? ? print timeElapsed()
> > ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> > ? ? outputfile = csv.writer(open(outputdir+file), 'w')
> > ? ? for row in reader:
> > ? ? ? ? if row[2] in IDs:
> > ? ? ? ? ? ? ouputfile.writerow(row)
> > ? ? ? ? else:
> > ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
> > ? ? ? ? ? ? ? ? outputfile.writerow(row)
> > ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> > ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> > ? ? ? ? ? ? else:
> > ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
> > ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> > ? ? currentfile+=1
>
> > print "Finished processing query logs and writing new files"
> > print "# of Query log entries removed:" , len(foundOnceInQuery)
> > print "Total Time Elapsed:", timeElapsed()
>
> Just a couple of ideas:
>
> 1) load the data into a sqlite3 database and use an SQL query to
> extract your results (has the potential of doing what you want without
> you coding it, plus if your requirements change, maybe somewhat more
> flexible)
>
> 2) Pre-sort your input files via ID, then match-merge (may add some
> time/space required to sort, but then the merge should be fairly
> quick, plus you'll have access to the entire row in the process, not
> just the ID)
>
> Jon.

Thanks Jon for the ideas, and yeah I might look into the SQLite
solution especially since I might need to do other sub selections. I
was also considering constructing a set for both install/update logs
and then another set for query logs and then do an intersection/other
set manipulations.

What I was really interested in was seeing if I could use generators
to try and accomplish what I'm doing especially since I'm uisng a lot
of for loops with conditionals and at this point it wouldn't matter if
the data is consumed in the intermediate steps before producing
output. Any help with getting this code in generator form would be
greatly appreciated.


From db3l.net at gmail.com  Fri Jul 17 19:09:35 2009
From: db3l.net at gmail.com (David Bolen)
Date: Fri, 17 Jul 2009 19:09:35 -0400
Subject: Why not enforce four space indentations in version 3.x?
References: <260f0f1f-1115-4db8-a955-74c9f459ecc3@h30g2000vbr.googlegroups.com>
	<87ljmwm7ri.fsf@benfinney.id.au>
	<34f9992c-92a4-4043-ac27-93119d68460c@b15g2000yqd.googlegroups.com>
	<mailman.3219.1247753940.8015.python-list@python.org>
	<pan.2009.07.16.20.15.13.719000@nowhere.com>
Message-ID: <m2skgudhzk.fsf@valheru.db3l.homeip.net>

Nobody <nobody at nowhere.com> writes:

> On Thu, 16 Jul 2009 09:18:47 -0500, Tim Chase wrote:
>
>> Yes, the dictatorial "a tab always equals 8 spaces"
>
> Saying "always" is incorrect; it is more accurate to say that tab stops
> are every 8 columns unless proven otherwise, with the burden of proof
> falling on whoever wants to use something different.

I suspect Tim was referring to the Python tokenizer.  Internally,
barring the existence of one of a few Emacs/vi tab setting commands in
the file, Python always assigns the logical indentation level for a
tab to align with the next multiple-of-8 column.  This is unrelated to
how someone might choose to display such a file.

So mixing tabs and spaces and using a visual display setting of
something other than 8 for the tab size (other than one consistent
with an instruction embedded in the file) can yield a discrepancy
between what is shown on the screen and how the same code is perceived
by the Python compiler.  This in turn may cause errors or code to
execute at different indent levels than expected.  Thus, in general,
such a mixture is a bad idea, and as per this thread, no longer
permitted in a single block in Python 3.x.

-- David


From dresdek at gmail.com  Fri Jul 17 19:13:16 2009
From: dresdek at gmail.com (Matt)
Date: Fri, 17 Jul 2009 16:13:16 -0700 (PDT)
Subject: Unable to get Tkinter menubar to appear under OS X
References: <3737fd18-4973-4cc3-914d-fbdefdbbb8a7@t10g2000vbg.googlegroups.com>
	<6a9b0831-ce2e-417b-ab4b-419629d0a25d@u16g2000pru.googlegroups.com>
Message-ID: <a0280a4c-fa6c-46fd-91d0-c382e54b52e3@d4g2000prc.googlegroups.com>

same problem on OS 10.4, menu doesn't show up on either from tkinter
or wxpython, continuing search..


From ben+python at benfinney.id.au  Fri Jul 17 19:25:47 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 18 Jul 2009 09:25:47 +1000
Subject: Propagate import for all modules in a package.
References: <9781e3be-9b58-43ee-be64-3b57572d5a0d@c29g2000yqd.googlegroups.com>
Message-ID: <87ws66evt0.fsf@benfinney.id.au>

Phil <phily05 at gmail.com> writes:

> I was thinking that I could just, for example, 'from datetime import
> datetime' in __init__.py and have the ability to use 'datetime'
> anywhere in any of the modules in 'package'.

That would break one of the very nice features of Python's namespace
system: that, because nothing[0] comes into a module without an explicit
?import foo?, you can always trace where ?foo? came from in the source
code.

> This didn't work for me. Did I just do something wrong? Is what I am
> trying to do possible?

If it were possible, we'd have the nightmare of not knowing where the
names in a module were coming from, without having to search all over
the package just to find where these implicit imports were taking place.
No, thanks; I'm glad it's not possible.

> Thanks in advance.

[0] Two exceptions: There are a certain number of built-in names,
    strictly limited and well documented in the standard Python
    documentation. There are also those who use a namespace-clobbering
    ?from foo import *?, to which the solution is a clue-bat applied to
    the back of the skull.

-- 
 \        ?Pinky, are you pondering what I'm pondering?? ?Wuh, I think |
  `\      so, Brain, but how will we get three pink flamingos into one |
_o__)                     pair of Capri pants?? ?_Pinky and The Brain_ |
Ben Finney


From joncle at googlemail.com  Fri Jul 17 19:31:43 2009
From: joncle at googlemail.com (Jon Clements)
Date: Fri, 17 Jul 2009 16:31:43 -0700 (PDT)
Subject: Generator Expressions and CSV
References: <8b0b135b-7bb5-45e4-b437-9308e787884d@t13g2000yqt.googlegroups.com>
	<mailman.3306.1247856555.8015.python-list@python.org>
	<71cfe652-0784-4612-82f8-26c2bf882980@v20g2000yqm.googlegroups.com>
	<51ce01d3-4620-4e5f-b5b5-bd0e9fd6fd2c@w41g2000yqb.googlegroups.com> 
	<8298385a-6f4b-44a5-b171-4871833f8dd2@c36g2000yqn.googlegroups.com>
Message-ID: <3ba0cc18-2cd0-416c-ad69-c7be138607e0@k1g2000yqf.googlegroups.com>

On 17 July, 23:57, Zaki <zaki.raha... at gmail.com> wrote:
> On Jul 17, 6:40?pm, Jon Clements <jon... at googlemail.com> wrote:
>
>
>
> > On 17 July, 21:08, Zaki <zaki.raha... at gmail.com> wrote:
>
> > > On Jul 17, 2:49?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>
> > > > Zaki wrote:
> > > > > Hey all,
>
> > > > > I'm really new to Python and this may seem like a really dumb
> > > > > question, but basically, I wrote a script to do the following, however
> > > > > the processing time/memory usage is not what I'd like it to be. Any
> > > > > suggestions?
>
> > > > > Outline:
> > > > > 1. Read tab delim files from a directory, files are of 3 types:
> > > > > install, update, and q. All 3 types contain ID values that are the
> > > > > only part of interest.
> > > > > 2. Using set() and set.add(), generate a list of unique IDs from
> > > > > install and update files.
> > > > > 3. Using the set created in (2), check the q files to see if there are
> > > > > matches for IDs. Keep all matches, and add any non matches (which only
> > > > > occur once in the q file) to a queue of lines to be removed from teh q
> > > > > files.
> > > > > 4. Remove the lines in the q for each file. (I haven't quite written
> > > > > the code for this, but I was going to implement this using csv.writer
> > > > > and rewriting all the lines in the file except for the ones in the
> > > > > removal queue).
>
> > > > > Now, I've tried running this and it takes much longer than I'd like. I
> > > > > was wondering if there might be a better way to do things (I thought
> > > > > generator expressions might be a good way to attack this problem, as
> > > > > you could generate the set, and then check to see if there's a match,
> > > > > and write each line that way).
>
> > > > Why are you checking and removing lines in 2 steps? Why not copy the
> > > > matching lines to a new q file and then replace the old file with the
> > > > new one (or, maybe, delete the new q file if no lines were removed)?
>
> > > That's what I've done now.
>
> > > Here is the final code that I have running. It's very much 'hack' type
> > > code and not at all efficient or optimized and any help in optimizing
> > > it would be greatly appreciated.
>
> > > import csv
> > > import sys
> > > import os
> > > import time
>
> > > begin = time.time()
>
> > > #Check minutes elapsed
> > > def timeElapsed():
> > > ? ? current = time.time()
> > > ? ? elapsed = current-begin
> > > ? ? return round(elapsed/60)
>
> > > #USAGE: python logcleaner.py <input_dir> <output_dir>
>
> > > inputdir = sys.argv[1]
> > > outputdir = sys.argv[2]
>
> > > logfilenames = os.listdir(inputdir)
>
> > > IDs = set() #IDs from update and install logs
> > > foundOnceInQuery = set()
> > > #foundTwiceInQuery = set()
> > > #IDremovalQ = set() Note: Unnecessary, duplicate of foundOnceInQuery;
> > > Queue of IDs to remove from query logs (IDs found only once in query
> > > logs)
>
> > > #Generate Filename Queues For Install/Update Logs, Query Logs
> > > iNuQ = []
> > > queryQ = []
>
> > > for filename in logfilenames:
> > > ? ? if filename.startswith("par1.install") or filename.startswith
> > > ("par1.update"):
> > > ? ? ? ? iNuQ.append(filename)
> > > ? ? elif filename.startswith("par1.query"):
> > > ? ? ? ? queryQ.append(filename)
>
> > > totalfiles = len(iNuQ) + len(queryQ)
> > > print "Total # of Files to be Processed:" , totalfiles
> > > print "Install/Update Logs to be processed:" , len(iNuQ)
> > > print "Query logs to be processed:" , len(queryQ)
>
> > > #Process install/update queue to generate list of valid IDs
> > > currentfile = 1
> > > for file in iNuQ:
> > > ? ? print "Processing", currentfile, "install/update log out of", len
> > > (iNuQ)
> > > ? ? print timeElapsed()
> > > ? ? reader = csv.reader(open(inputdir+file),delimiter = '\t')
> > > ? ? for row in reader:
> > > ? ? ? ? IDs.add(row[2])
> > > ? ? currentfile+=1
>
> > > print "Finished processing install/update logs"
> > > print "Unique IDs found:" , len(IDs)
> > > print "Total Time Elapsed:", timeElapsed()
>
> > > currentfile = 1
> > > for file in queryQ:
> > > ? ? print "Processing", currentfile, "query log out of", len(queryQ)
> > > ? ? print timeElapsed()
> > > ? ? reader = csv.reader(open(inputdir+file), delimiter = '\t')
> > > ? ? outputfile = csv.writer(open(outputdir+file), 'w')
> > > ? ? for row in reader:
> > > ? ? ? ? if row[2] in IDs:
> > > ? ? ? ? ? ? ouputfile.writerow(row)
> > > ? ? ? ? else:
> > > ? ? ? ? ? ? if row[2] in foundOnceInQuery:
> > > ? ? ? ? ? ? ? ? foundOnceInQuery.remove(row[2])
> > > ? ? ? ? ? ? ? ? outputfile.writerow(row)
> > > ? ? ? ? ? ? ? ? #IDremovalQ.remove(row[2])
> > > ? ? ? ? ? ? ? ? #foundTwiceInQuery.add(row[2])
>
> > > ? ? ? ? ? ? else:
> > > ? ? ? ? ? ? ? ? foundOnceInQuery.add(row[2])
> > > ? ? ? ? ? ? ? ? #IDremovalQ.add(row[2])
>
> > > ? ? currentfile+=1
>
> > > print "Finished processing query logs and writing new files"
> > > print "# of Query log entries removed:" , len(foundOnceInQuery)
> > > print "Total Time Elapsed:", timeElapsed()
>
> > Just a couple of ideas:
>
> > 1) load the data into a sqlite3 database and use an SQL query to
> > extract your results (has the potential of doing what you want without
> > you coding it, plus if your requirements change, maybe somewhat more
> > flexible)
>
> > 2) Pre-sort your input files via ID, then match-merge (may add some
> > time/space required to sort, but then the merge should be fairly
> > quick, plus you'll have access to the entire row in the process, not
> > just the ID)
>
> > Jon.
>
> Thanks Jon for the ideas, and yeah I might look into the SQLite
> solution especially since I might need to do other sub selections. I
> was also considering constructing a set for both install/update logs
> and then another set for query logs and then do an intersection/other
> set manipulations.
>
> What I was really interested in was seeing if I could use generators
> to try and accomplish what I'm doing especially since I'm uisng a lot
> of for loops with conditionals and at this point it wouldn't matter if
> the data is consumed in the intermediate steps before producing
> output. Any help with getting this code in generator form would be
> greatly appreciated.

Well effectively, you are using generators.

A very small optimisation might be to load the smallest set of data
first (if you are already, I apologise!). Read the others and see if
it's a matching ID, where it is, remove it from the smallest set, and
those are the records to be added on the next parse.

Posting when tired, so hope that makes some sense!

Otherwise, I'd be tempted to pre-sort or use sqlite.


From zac256 at gmail.com  Fri Jul 17 20:31:44 2009
From: zac256 at gmail.com (Zac Burns)
Date: Fri, 17 Jul 2009 17:31:44 -0700
Subject: Self optimizing iterable
Message-ID: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>

Greetings,

I would like a set like object that when iterated maintains a count of
where iteration stopped and then re-orders itself based on that count
so that the iteration stopped on the most bubble to the top.

An example use case for this would be for something like a large table
of regular expressions that would be iterated over trying to match in
some string. If some regular expressions are more statistically more
successful then the iteration will generally be short.

Does anyone know of a pre-existing recipe for this or feel like taking
on the challenge?

Bonus points for:
   Best possible BigO notation on switching order and iteration
   Threadsafety
   Extend to also include a mapping version



--
Zachary Burns
(407)590-4814
Aim - Zac256FL
Production Engineer (Digital Overlord)
Zindagi Games


From http  Fri Jul 17 20:40:32 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 17:40:32 -0700
Subject: Self optimizing iterable
References: <mailman.3325.1247877108.8015.python-list@python.org>
Message-ID: <7xbpniombj.fsf@ruckus.brouhaha.com>

Zac Burns <zac256 at gmail.com> writes:
> An example use case for this would be for something like a large table
> of regular expressions that would be iterated over trying to match in
> some string. If some regular expressions are more statistically more
> successful then the iteration will generally be short.

Generally if you are matching against a bunch of regexps, they will
tend to match overlapping sets, so you want to control precisely what
order they are tested in.  Having stuff bubble around based on hit
counts doesn't sound good.


From zac256 at gmail.com  Fri Jul 17 20:43:21 2009
From: zac256 at gmail.com (Zac Burns)
Date: Fri, 17 Jul 2009 17:43:21 -0700
Subject: Retrieving a partial pickle
Message-ID: <333edbe80907171743n6e72f5b8p7c1c6ab668cff7df@mail.gmail.com>

I have a large pickle file, which happens to be a list with lots of
objects in it.

What sort of things can I do without unpickling the whole object?

I would particularly like to retrieve one of the elements in the list
without unpicking the whole object.

If the answer is not specific to lists that would be useful (works on
getting items in a dictionary, or doing introspection on the objects
or whatever)

--
Zachary Burns
(407)590-4814
Aim - Zac256FL
Production Engineer (Digital Overlord)
Zindagi Games


From python at mrabarnett.plus.com  Fri Jul 17 20:54:22 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 18 Jul 2009 01:54:22 +0100
Subject: Self optimizing iterable
In-Reply-To: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>
References: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>
Message-ID: <4A611D3E.90806@mrabarnett.plus.com>

Zac Burns wrote:
> Greetings,
> 
> I would like a set like object that when iterated maintains a count of
> where iteration stopped and then re-orders itself based on that count
> so that the iteration stopped on the most bubble to the top.
> 
> An example use case for this would be for something like a large table
> of regular expressions that would be iterated over trying to match in
> some string. If some regular expressions are more statistically more
> successful then the iteration will generally be short.
> 
> Does anyone know of a pre-existing recipe for this or feel like taking
> on the challenge?
> 
> Bonus points for:
>    Best possible BigO notation on switching order and iteration
>    Threadsafety
>    Extend to also include a mapping version
> 
That's not a set, but a Most Recently Used list.


From gagsl-py2 at yahoo.com.ar  Fri Jul 17 21:09:22 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 17 Jul 2009 22:09:22 -0300
Subject: Self optimizing iterable
References: <333edbe80907171731m8e8baf7i26d8b7f17275149d@mail.gmail.com>
Message-ID: <op.uw8n5wfkx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 21:31:44 -0300, Zac Burns <zac256 at gmail.com> escribi?:

> I would like a set like object that when iterated maintains a count of
> where iteration stopped and then re-orders itself based on that count
> so that the iteration stopped on the most bubble to the top.
>
> An example use case for this would be for something like a large table
> of regular expressions that would be iterated over trying to match in
> some string. If some regular expressions are more statistically more
> successful then the iteration will generally be short.

If you require a certain order, it's not a set; better to use a list.
The code below extends the builtin list type to add a "promote" method;  
lst.promote(3) "bubbles" lst[3] up (exchanging lst[3] with lst[2]). It's  
thread safe, and O(1).

<code>
import threading

class XList(list):
   #
   @property
   def lock(self):
     lock = getattr(self, '_lock', None)
     if lock is None: lock = self._lock = threading.Lock()
     return lock
   #
   def promote(self, index):
     if index<0: index += len(self)
     if index>0:
       with self.lock:
         self[index], self[index-1] = self[index-1], self[index]
</code>

py> a = XList('python')
py> a
['p', 'y', 't', 'h', 'o', 'n']
py> a.promote(3)
py> a
['p', 'y', 'h', 't', 'o', 'n']
py> a.promote(2)
py> a
['p', 'h', 'y', 't', 'o', 'n']
py> a.promote(-1)
py> a
['p', 'h', 'y', 't', 'n', 'o']
py> a.promote(0)
py> a
['p', 'h', 'y', 't', 'n', 'o']

An example, looking for a matching regular expression:

for index,expr in enumerate(exprlist):
   m = expr.match(txt)
   if m:
      dosomethingwith(m)
      exprlist.promote(index)
      break

After many calls, the most frequently matched expressions appear towards  
the front of the list.

>    Extend to also include a mapping version

I'm unsure if this point is still applicable. I'm using a list here, not a  
set as in your original proposal.

-- 
Gabriel Genellina



From pfeldman at verizon.net  Fri Jul 17 21:09:37 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 17 Jul 2009 18:09:37 -0700 (PDT)
Subject: missing 'xor' Boolean operator
In-Reply-To: <4A5DE5E7.5070003@mrabarnett.plus.com>
References: <24485116.post@talk.nabble.com>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<4A5DE5E7.5070003@mrabarnett.plus.com>
Message-ID: <24543805.post@talk.nabble.com>


Suppose that 'xor' returns the value that is true when only one value is
true, and False otherwise.  This definition of xor doesn't have the standard
associative property, that is,

(a xor b) xor c

will not necessarily equal

a xor (b xor c)

To see that this is the case, let a= 1, b= 2, and c= 3.

(a xor b) xor c

yields 3, while

a xor (b xor c)

yields 1.  So, I'd prefer an xor operator that simply returns True or False.

Phillip


MRAB-2 wrote:
> 
> 
> <snip>
> 
> What values should 'xor' return? IMHO, if only one of the values is true
> then it should return that value, otherwise it should return False.
> 
>      1 xor 0 => 1
>      0 xor 2 => 2
>      1 xor 2 => False
>      0 xor 0 => False
> 
> This is because it's a Boolean operator, so it should fall back to
> Boolean values when necessary, like 'not':
> 
>      not 0 => True
>      not 1 => False
> 
> Also:
> 
>      x and y and z => (x and y) and z
>      x or y or z => (x or y) or z
> 
> therefore:
> 
>      x xor y xor z => (x xor y) xor z
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/missing-%27xor%27-Boolean-operator-tp24485116p24543805.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From pfeldman at verizon.net  Fri Jul 17 21:12:31 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 17 Jul 2009 18:12:31 -0700 (PDT)
Subject: PDF version of Python Tutorial?
Message-ID: <24543817.post@talk.nabble.com>


Does anyone know if there is a PDF version of the Python Tutorial (URL=
http://www.python.org/doc/current/tutorial/)?
-- 
View this message in context: http://www.nabble.com/PDF-version-of-Python-Tutorial--tp24543817p24543817.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From pavlovevidence at gmail.com  Fri Jul 17 21:35:33 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 17 Jul 2009 18:35:33 -0700 (PDT)
Subject: Self optimizing iterable
References: <mailman.3325.1247877108.8015.python-list@python.org> 
	<7xbpniombj.fsf@ruckus.brouhaha.com>
Message-ID: <97c6fdf0-0364-4669-bdd5-35e8b567a38c@o36g2000vbl.googlegroups.com>

On Jul 17, 5:40?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Zac Burns <zac... at gmail.com> writes:
> > An example use case for this would be for something like a large table
> > of regular expressions that would be iterated over trying to match in
> > some string. If some regular expressions are more statistically more
> > successful then the iteration will generally be short.
>
> Generally if you are matching against a bunch of regexps, they will
> tend to match overlapping sets, so you want to control precisely what
> order they are tested in. ?Having stuff bubble around based on hit
> counts doesn't sound good.

As a corrollary, if you happen to be matching non-overlapping sets,
then it is a red flag that there could be some other (better) way to
dispatch than a linear regexp search.  For instance, if all your
regexps start with a different keyword, then you should dispatch on
that keyword using a dictionary.  A regexp can be used after
dispatching to extract parameters if necessary.

It's possible to have disjoint regexps without a simple dispatch
criterion, but I'd guess that's less common.


Carl Banks


From ronn.ross at gmail.com  Fri Jul 17 21:42:43 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Fri, 17 Jul 2009 21:42:43 -0400
Subject: Beginners question
Message-ID: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>

How do you define a global variable in a class. I tried this with do
success:
class ClassName:
    global_var = 1

    def some_methos():
        print global_var

This doesn't work. What am I doing wrong?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090717/0527713c/attachment-0001.html>

From sjmachin at lexicon.net  Fri Jul 17 21:54:11 2009
From: sjmachin at lexicon.net (John Machin)
Date: Fri, 17 Jul 2009 18:54:11 -0700 (PDT)
Subject: Find first matching substring
References: <2ac9b562-897e-450b-8d92-ef33c7fcc5e7@g23g2000vbr.googlegroups.com>
Message-ID: <470ebc06-3e84-41c8-bd8e-0a342bb4ea28@y10g2000prg.googlegroups.com>

On Jul 18, 2:11?am, Eloff <dan.el... at gmail.com> wrote:
> Almost every time I've had to do parsing of text over the last 5 years
> I've needed this function:
[snip]
> It finds the first matching substring in the target string, if there
> is more than one match, it returns the position of the match that
> occurs at the lowest index in the string.

Alternatives:
(1) re.search(r"sub0|sub1|...", ...)
(2) google "Aho Corasick Python" (one result should be a thread in
this newsgroup within the last week)


From gabrielmonnerat at gmail.com  Fri Jul 17 22:03:32 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Fri, 17 Jul 2009 23:03:32 -0300
Subject: Beginners question
In-Reply-To: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <4A612D74.80908@gmail.com>

Ronn Ross wrote:
> How do you define a global variable in a class. I tried this with do 
> success:
> class ClassName:
>     global_var = 1
>    
>     def some_methos():
>         print global_var
>
> This doesn't work. What am I doing wrong?
You need pass "self" to the function and "global_var" needs be called 
with self.

class ClassName:
    global_var = 1
   
    def some_methos(self):
        print self.global_var


Gabriel M. Monnerat


From marduk at letterboxes.org  Fri Jul 17 22:13:24 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Fri, 17 Jul 2009 22:13:24 -0400
Subject: Beginners question
In-Reply-To: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <1247883209.28511.8.camel@centar>

On Fri, 2009-07-17 at 21:42 -0400, Ronn Ross wrote:
> How do you define a global variable in a class.

I bit of a mix-up with words here.  A variable can be a class variable
or a global variable (wrt the module).. not both.

>  I tried this with do success:
> class ClassName:
>     global_var = 1
>     
>     def some_methos():
>         print global_var
> 
> This doesn't work. What am I doing wrong?

You could have posted the error message... Two things are wrong here.
The first, if some_methos() is a method of ClassName then it should have
at least one parameter, which is the instance of the class (i.e.
"self"), so

    def some_methos(self):

The second problem is that global_var is not local so you need to
specify the scope.  You can either use

    print ClassName.global_var

or

    print self.global_var

I'm not sure which one is better though I prefer the former because it
makes it clearer to the reader that it's a class variable and not an
instance variable.

HTH,
-a




From nohics at gmail.com  Fri Jul 17 22:40:32 2009
From: nohics at gmail.com (nohics nohics)
Date: Sat, 18 Jul 2009 03:40:32 +0100
Subject: Beginners question
In-Reply-To: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <e4de9e30907171940s28a161cct3bc362516a1a20a6@mail.gmail.com>

When defining your class methods, you *must* explicitly list self as the
first argument for each method, including __init__. When you call a method
of an ancestor class from within your class, you *must* include the
selfargument. But when you call your class method from outside, you do
not
specify anything for the self argument; you skip it entirely, and
Pythonautomatically adds the instance reference for you. I am aware
that this is
confusing at first; it's not really inconsistent, but it may appear
inconsistent because it relies on a distinction (between bound and unbound
methods) that you don't know about yet.

So, you have to do:

class ClassName:
    self.global_var = 1
    def some_methos(self):
        print self.global_var

2009/7/18 Ronn Ross <ronn.ross at gmail.com>

> How do you define a global variable in a class. I tried this with do
> success:
> class ClassName:
>     global_var = 1
>
>     def some_methos():
>         print global_var
>
> This doesn't work. What am I doing wrong?
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/472c1523/attachment-0001.html>

From contact at xavierho.com  Fri Jul 17 22:48:28 2009
From: contact at xavierho.com (Xavier Ho)
Date: Sat, 18 Jul 2009 10:48:28 +0800
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907171947s6a4a010fp124146d54d560bf4@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>
	<mailman.3275.1247836630.8015.python-list@python.org>
	<02707804$0$5185$c3e8da3@news.astraweb.com>
	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>
	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>
	<h3qs5u$1cr$1@ger.gmane.org>
	<2d56febf0907171507y75f6436ete75cb3f748ee838d@mail.gmail.com>
	<4A611D89.7040603@ieee.org>
	<2d56febf0907171947s6a4a010fp124146d54d560bf4@mail.gmail.com>
Message-ID: <2d56febf0907171948l35e73c14gf02bc3c6ef11d493@mail.gmail.com>

Darn it.

On Sat, Jul 18, 2009 at 8:55 AM, Dave Angel <davea at ieee.org> wrote:

>
> You don't need a counter.  len() will tell you the size of the list of
> primes.


Does len() go through and count by itself, or does it actually keep track of
the size and just return the memory? I always thought it would go through
and count, which may take some time. I could be wrong.

>
> And, just in case you're still interested, that
>     for i in range()
>
> earlier in the thread has the overhead of building a (possibly) large list
> of integers, just in case we might need to loop.


Right, so for i in xrange() would be a better choice?

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/64fe6804/attachment-0001.html>

From gabrielmonnerat at gmail.com  Fri Jul 17 23:06:31 2009
From: gabrielmonnerat at gmail.com (gabrielmonnerat)
Date: Sat, 18 Jul 2009 00:06:31 -0300
Subject: Beginners question
In-Reply-To: <e4de9e30907171940s28a161cct3bc362516a1a20a6@mail.gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
	<e4de9e30907171940s28a161cct3bc362516a1a20a6@mail.gmail.com>
Message-ID: <4A613C37.8090808@gmail.com>

nohics nohics wrote:
> When defining your class methods, you /must/ explicitly list self as 
> the first argument for each method, including __init__. When you call 
> a method of an ancestor class from within your class, you /must/ 
> include the self argument. But when you call your class method from 
> outside, you do not specify anything for the self argument; you skip 
> it entirely, and Python automatically adds the instance reference for 
> you. I am aware that this is confusing at first; it's not really 
> inconsistent, but it may appear inconsistent because it relies on a 
> distinction (between bound and unbound methods) that you don't know 
> about yet.
>
> So, you have to do:
>
> class ClassName:
>     self.global_var = 1
self isn't exists in this context.

 >>> class ClassName:
...       self.global_var = 1
...       def some_methods(self):
...         print self.global_var
...
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in ClassName
NameError: name 'self' is not defined

If you want a variable of instance you can use __init__

 >>> class ClassName:
...       def __init__(self):
...           self.global_var = 1
...       def some_methods(self):
...           print self.global_var

Now "global_var" is created when ClassName is instantiated

 >>> ClassName.global_var
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: class ClassName has no attribute 'global_var'
 >>> c = ClassName()
 >>> c.global_var
1

>     def some_methos(self):
>         print self.global_var
>
> 2009/7/18 Ronn Ross <ronn.ross at gmail.com <mailto:ronn.ross at gmail.com>>
>
>     How do you define a global variable in a class. I tried this with
>     do success:
>     class ClassName:
>         global_var = 1
>        
>         def some_methos():
>             print global_var
>
>     This doesn't work. What am I doing wrong?
>
>     --
>     http://mail.python.org/mailman/listinfo/python-list
>
>



From drobinow at gmail.com  Fri Jul 17 23:09:44 2009
From: drobinow at gmail.com (David Robinow)
Date: Fri, 17 Jul 2009 23:09:44 -0400
Subject: PDF version of Python Tutorial?
In-Reply-To: <24543817.post@talk.nabble.com>
References: <24543817.post@talk.nabble.com>
Message-ID: <4eb0089f0907172009t1ba9331bx24042c497b1d2b96@mail.gmail.com>

On Fri, Jul 17, 2009 at 9:12 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Does anyone know if there is a PDF version of the Python Tutorial (URL=
> http://www.python.org/doc/current/tutorial/)?

http://docs.python.org/download.html


From gagsl-py2 at yahoo.com.ar  Fri Jul 17 23:34:35 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 18 Jul 2009 00:34:35 -0300
Subject: PDF version of Python Tutorial?
References: <24543817.post@talk.nabble.com>
Message-ID: <op.uw8s1szxx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 22:12:31 -0300, Dr. Phillip M. Feldman
<pfeldman at verizon.net> escribi?:

> Does anyone know if there is a PDF version of the Python Tutorial (URL=
> http://www.python.org/doc/current/tutorial/)?

  From that page, click on the top left corner to go up one level, and
you'll see a download link.
Or, starting on http://www.python.org/doc/ you can navigate to the desired
document.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 17 23:34:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 18 Jul 2009 00:34:39 -0300
Subject: Beginners question
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
Message-ID: <op.uw8utxorx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 22:42:43 -0300, Ronn Ross <ronn.ross at gmail.com>
escribi?:

> How do you define a global variable in a class. I tried this with do
> success:
> class ClassName:
>     global_var = 1
>
>     def some_method(self):
>         print global_var
>
> This doesn't work. What am I doing wrong?

[some typos fixed]

In Python, a "variable" is just a name in a namespace that references
another object.
There are five possible namespaces here:

- The local namespace, that is, the namespace inside some_method. All
assigned-to names that appear inside the function (there is none in this
case) are in the local namespace. But you're not interested on these local
names, I presume, because you said "global"

- The global namespace: the namespace of the module containing the code
(NOT a "super-global" namespace shared by all modules). Names in this
namespace are "global" in the sense that all code in the same module can
reference them. But they're not restricted to any class, as you requested.
To use a global name in an expression, just write it. To assign a new
value to a global name, you must use the "global" statement if you're
inside a function (else, it's considered a local name, see above).

- The built-in namespace: like a super-global namespace, it is searched
last when looking for an unqualified name; by example, the "len" function.
For most purposes, you should consider the built-in namespace read-only.

- The instance namespace: each object has its own namespace; you access
its names using dotted attributes: obj.name -- or self.attribute when
inside a method. The instance namespace is not determined by the object
type or class; any object may contain any attribute name (in general).

- The class namespace: classes may contain attributes too (like any other
object, because classes are objects too). In your code above, you may use
ClassName.global_var to refer to such class attribute. To resolve a dotted
attribute name, Python searches the instance first -- and if no match is
found, then the class namespace is searched too: this way, class
attributes effectively are "default values" for instance attributes. Since
all existing instances of a certain class share the same class, this is
like a "shared attribute" between all instances (like "static members" in
other languages). Inside some_method above, you may use self.global_var or
ClassName.global_var -- but once you *assign* something to the instance
attribute (self.global_var = xxx), the class attribute is shadowed and you
may reference it using ClassName.global_var only.

-- 
Gabriel Genellina



From drobinow at gmail.com  Fri Jul 17 23:51:46 2009
From: drobinow at gmail.com (David Robinow)
Date: Fri, 17 Jul 2009 23:51:46 -0400
Subject: turtle dump
In-Reply-To: <h3qn5k$jot$1@ger.gmane.org>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com> <h3obqg$aru$1@ger.gmane.org>
	<mailman.3246.1247792169.8015.python-list@python.org>
	<h3p5mm$o6s$01$1@news.t-online.com> <h3qn5k$jot$1@ger.gmane.org>
Message-ID: <4eb0089f0907172051v1b206a47r4326e7447f3d0637@mail.gmail.com>

>> If you want to generate high-quality graphics easily you need different
>> primitives.
>>
>> http://cairographics.org
>>
>> has Python bindings, but I don't know if it's available on Windows.
>
> Effectively not, as far as I can tell. PyCairo appears to be *nix and
> require later binaries than those available from gtk site referenced from
> cairo site.

http://ftp.gnome.org/pub/GNOME/binaries/win32/pycairo/1.4/
 Works for me.


From gagsl-py2 at yahoo.com.ar  Sat Jul 18 00:13:18 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 18 Jul 2009 01:13:18 -0300
Subject: Retrieving a partial pickle
References: <333edbe80907171743n6e72f5b8p7c1c6ab668cff7df@mail.gmail.com>
Message-ID: <op.uw8woga0x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 21:43:21 -0300, Zac Burns <zac256 at gmail.com> escribi?:

> I have a large pickle file, which happens to be a list with lots of
> objects in it.
>
> What sort of things can I do without unpickling the whole object?
>
> I would particularly like to retrieve one of the elements in the list
> without unpicking the whole object.

I'm afraid you can't do that, in general. A pickle is actually *code* for  
a stack-based machine; you have to execute all the previous instructions  
to have a sane stack contents; it's not possible (at least, not easily)  
just to jump in the middle of the pickle and execute just a section.

> If the answer is not specific to lists that would be useful (works on
> getting items in a dictionary, or doing introspection on the objects
> or whatever)

The pickletools module might be a starting point:  
http://docs.python.org/library/pickletools.html -- Try the Python Cookbook  
too http://code.activestate.com/recipes/langs/python/

-- 
Gabriel Genellina



From http  Sat Jul 18 00:47:03 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 21:47:03 -0700
Subject: Einstein summation notation
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>
	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>
	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>
	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>
	<kmr2uu.d1t@spenarnc.xs4all.nl>
	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>
	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>
	<02701951$0$5185$c3e8da3@news.astraweb.com>
	<7xljmnahlj.fsf@ruckus.brouhaha.com>
	<02706d8f$0$5185$c3e8da3@news.astraweb.com>
	<7xab33s8ik.fsf@ruckus.brouhaha.com>
	<mailman.3290.1247847474.8015.python-list@python.org>
Message-ID: <7xprbybnso.fsf@ruckus.brouhaha.com>

Ethan Furman <ethan at stoneleaf.us> writes:
> Or if any(p for p in [header, body, footer, whatever, ...])

No need for the genexp:

   if any([header, body, footer, whatever, ...])

But, you are using the built-in bool cast either way.


From http  Sat Jul 18 00:49:02 2009
From: http (Paul Rubin)
Date: 17 Jul 2009 21:49:02 -0700
Subject: Retrieving a partial pickle
References: <mailman.3326.1247877803.8015.python-list@python.org>
Message-ID: <7xljmmbnpd.fsf@ruckus.brouhaha.com>

Zac Burns <zac256 at gmail.com> writes:
> I have a large pickle file, which happens to be a list with lots of
> objects in it.
> What sort of things can I do without unpickling the whole object?

If it's for some kind of data recovery of a busted file, you could
code some awful hack to pull stuff out of the middle of the pickle,
but that's not the idea.  You may want the shelve module.


From torriem at gmail.com  Sat Jul 18 00:49:52 2009
From: torriem at gmail.com (Michael Torrie)
Date: Fri, 17 Jul 2009 22:49:52 -0600
Subject: getopt code NameError exception on logTail.py
In-Reply-To: <e8075cdd0907171132m361906fbw97dd20a58c930743@mail.gmail.com>
References: <e8075cdd0907171020s58a6cff9j86a66f16d41220a2@mail.gmail.com>	<4A60BE10.5050905@mrabarnett.plus.com>
	<e8075cdd0907171132m361906fbw97dd20a58c930743@mail.gmail.com>
Message-ID: <4A615470.9080503@gmail.com>

LoD MoD wrote:
> In this instance the trackback was somewhat unhelpful.There problem was
> here:
> 
>            file = open(filename, 'r')
> 
> should be
> 
>            file = open(a, 'r')
> 
> args should be passed within the getopt riff

Well given the code you posted, this little "problem" you mention has
nothing to do with the traceback.  The code (as you posted it) still
does not define "process" anywhere.  Seems helpful enough to me.  If
you're not importing it from somewhere, then saying "it's defined
elsewhere" is still an error!


From torriem at gmail.com  Sat Jul 18 00:55:26 2009
From: torriem at gmail.com (Michael Torrie)
Date: Fri, 17 Jul 2009 22:55:26 -0600
Subject: Question regarding style/design..
In-Reply-To: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
References: <3f1a902d0907170931v19a0c37ax398e782f604d788e@mail.gmail.com>
Message-ID: <4A6155BE.80500@gmail.com>

Wells Oliver wrote:
> Sometimes I see relatively small application, generally task scripts,
> written as essentially a list of statements. Other times, I see them neatly
> divided into functions and then the "if __name__ == '__main__':" convention.
> Is there a preference? Is there an... application scope such that the
> preference shifts from the former to the latter? I understand the use of the
> __name__ == 'main' convention for building unit tests, but I'm mixed on
> using it in scripts/small applications.
> Thanks for any thoughts!

I always use the name guard thing for the simple reason that it lets me
reuse code by importing it as a module into other things.  My programs
often serve double purposes.  One is to be a standalone utility.  The
other is to be able to be used as a library from other code.  So the
name guard is essential.  For code that is intended to be in modules,
the name guard thing is indispensable for running unit tests.

For very short, one-off things, I may leave it off.  In any case I much
prefer having a name guard, then running various functions than the Java
style of writing a stupid static class with a static main method.
Always seemed like a paradigm hack to me.


From electronixtar at gmail.com  Sat Jul 18 01:03:05 2009
From: electronixtar at gmail.com (est)
Date: Fri, 17 Jul 2009 22:03:05 -0700 (PDT)
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
Message-ID: <0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>

On Jul 17, 10:48?am, Christian Tismer <tis... at stackless.com> wrote:
> Announcing Psyco V2 source release
> ----------------------------------
>
> This is the long awaited announcement of Psyco V2.
>
> Psyco V2 is a continuation of the well-known psyco project,
> which was called finished and was dis-continued by its author
> Armin Rigo in 2005, in favor of the PyPy project.
>
> This is a new project, using Psyco's code base with permission
> of Armin. Questions and complaints should go to me
> (tis... at stackless.com) or the mailing list
> (psyco-de... at lists.sourceforge.net);
> Armin is explicitly not in charge of (t)his project any longer!
>
> As one of the founders and an active member of the PyPy
> project, I was very happy to be invited to work on Psyco
> V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
> approach "an extension module that just makes Python faster".
>
> Psyco is a just-in-time compiler that accelerates arbitrary
> Python code by specialization. We believe that Psyco's approach
> can be carried out much further than it was tried so far, when
> it's first version was abandoned.
>
> This first V2 release is source-only. There is no web-site, yet,
> and there are no binaries for download. These will be available
> in a few days onhttp://www.psyco.org.
>
> For the time being, please stick with subversion access,
> building the extension module from source code. The repository
> is here:
>
> ? ? ?http://codespeak.net/svn/psyco/v2/dist
>
> Check-out the repository, and run the setup.py script,
> given that you have access to a C compiler.
>
> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
> is well being considered.
>
> The current improvements are, shortly:
>
> ? ?- Support for Python 2.4, 2.5 and 2.6
> ? ?- a lot of new builtins
> ? ?- generators, fast and fully supported.
>
> More information is coming soon onhttp://www.psyco.org.
>
> This is the beginning of a series of new Psyco versions.
> Many more improvements are prepared and about to be published,
> soon, starting with the current version 2.0.0 .
>
> Stay tuned, this is just the beginning of psyco's re-birth!
>
> For questions about Psyco V2, please join the mailing list
>
> ? ? ?psyco-de... at lists.sourceforge.net
>
> or contact me on IRC:
>
> ? ? ?#psyco on irc.freenode.net .
>
> Psyco V2 is fundamentally supported by FATTOC, LLC.
> Seehttp://www.fattoc.com.
>
> Without their continuous support, this work would not have
> been possible at all. I wish to express my deepest thanks
> to FATTOC, for allowing me to continue on Psyco with all the
> energy that this ambitious project needs, and will need.
>
> Further special thanks are going to
> Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
> Raymond Hettinger, Fabrizio Milo, Michael Foord,
> Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
> for all the support and discussions.
>
> Looking forward to a great future of Psyco!
>
> July 17, 2009
> --
> Christian Tismer ? ? ? ? ? ? :^) ? <mailto:tis... at stackless.com>
> tismerysoft GmbH ? ? ? ? ? ? : ? ? Have a break! Take a ride on Python's
> Johannes-Niemeyer-Weg 9A ? ? : ? ?*Starship*http://starship.python.net/
> 14109 Berlin ? ? ? ? ? ? ? ? : ? ? PGP key ->http://wwwkeys.pgp.net/
> work +49 30 802 86 56 ?mobile +49 173 24 18 776 ?fax +49 30 80 90 57 05
> PGP 0x57F3BF04 ? ? ? 9064 F4E1 D754 C2FF 1619 ?305B C09C 5A3B 57F3 BF04
> ? ? ? ?whom do you want to sponsor today? ?http://www.stackless.com/

congrats!

btw is psyco.org owned?


From tjreedy at udel.edu  Sat Jul 18 01:44:58 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 18 Jul 2009 01:44:58 -0400
Subject: turtle dump
In-Reply-To: <4eb0089f0907172051v1b206a47r4326e7447f3d0637@mail.gmail.com>
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>	<h3n7fb$b0h$00$1@news.t-online.com>
	<4A5F287B.2000503@xs4all.nl>	<mailman.3238.1247776983.8015.python-list@python.org>	<h3o6hr$mmh$02$1@news.t-online.com>
	<h3obqg$aru$1@ger.gmane.org>	<mailman.3246.1247792169.8015.python-list@python.org>	<h3p5mm$o6s$01$1@news.t-online.com>
	<h3qn5k$jot$1@ger.gmane.org>
	<4eb0089f0907172051v1b206a47r4326e7447f3d0637@mail.gmail.com>
Message-ID: <h3rngr$j5i$1@ger.gmane.org>

David Robinow wrote:
>>> If you want to generate high-quality graphics easily you need different
>>> primitives.
>>>
>>> http://cairographics.org
>>>
>>> has Python bindings, but I don't know if it's available on Windows.
>> Effectively not, as far as I can tell. PyCairo appears to be *nix and
>> require later binaries than those available from gtk site referenced from
>> cairo site.
> 
> http://ftp.gnome.org/pub/GNOME/binaries/win32/pycairo/1.4/
>  Works for me.

Thanks. I did not see that referenced from the cairo site. Now if only 
there were a 3.1 version....

tjr



From __peter__ at web.de  Sat Jul 18 02:42:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 08:42:15 +0200
Subject: turtle dump
References: <4a5f0773$0$18927$4fafbaef@reader2.news.tin.it>
	<7c8g58F26vgl2U4@mid.uni-berlin.de>
	<4a5f0c9c$0$18927$4fafbaef@reader2.news.tin.it>
	<77e991d3-bb94-42b9-9d78-b61db536569a@d15g2000prc.googlegroups.com>
	<4a5f18dd$0$18933$4fafbaef@reader2.news.tin.it>
	<h3n7fb$b0h$00$1@news.t-online.com> <4A5F287B.2000503@xs4all.nl>
	<mailman.3238.1247776983.8015.python-list@python.org>
	<h3o6hr$mmh$02$1@news.t-online.com>
	<mailman.3245.1247785636.8015.python-list@python.org>
	<364d422c-118b-4654-bfeb-9ed1ae468426@12g2000pri.googlegroups.com>
	<mailman.3313.1247863203.8015.python-list@python.org>
Message-ID: <h3rqrp$536$01$1@news.t-online.com>

Terry Reedy wrote:

> alex23 wrote:
> 
>> The help in iPython says the same, but also mentions that it's a
>> dynamically generated function, so it may not be picking up the
>> docstring that way. turtle.ScrolledCanvas.postscript is similarly
>> terse, but you can find more info in turtle.Canvas.postscript:
>> 
>>   Print the contents of the canvas to a postscript
>>   file. Valid options: colormap, colormode, file, fontmap,
>>   height, pageanchor, pageheight, pagewidth, pagex, pagey,
>>   rotate, witdh, x, y.
> 
> How, exactly, did you get that list?
> 
> tjr

[Python 3.1]
>>> import tkinter
>>> print(tkinter.Canvas.postscript.__doc__)
Print the contents of the canvas to a postscript
        file. Valid options: colormap, colormode, file, fontmap,
        height, pageanchor, pageheight, pagewidth, pagex, pagey,
        rotate, witdh, x, y.

Peter



From tismer at stackless.com  Sat Jul 18 02:50:07 2009
From: tismer at stackless.com (Christian Tismer)
Date: Sat, 18 Jul 2009 08:50:07 +0200
Subject: ANN: psyco V2
In-Reply-To: <0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>
Message-ID: <5661F6B6-371B-46C3-BAE6-FFE280DC78A3@stackless.com>

It is just being transferred

Von meinem iTouch gesendet

On Jul 18, 2009, at 7:03, est <electronixtar at gmail.com> wrote:

> On Jul 17, 10:48 am, Christian Tismer <tis... at stackless.com> wrote:
>> Announcing Psyco V2 source release
>> ----------------------------------
>>
>> This is the long awaited announcement of Psyco V2.
>>
>> Psyco V2 is a continuation of the well-known psyco project,
>> which was called finished and was dis-continued by its author
>> Armin Rigo in 2005, in favor of the PyPy project.
>>
>> This is a new project, using Psyco's code base with permission
>> of Armin. Questions and complaints should go to me
>> (tis... at stackless.com) or the mailing list
>> (psyco-de... at lists.sourceforge.net);
>> Armin is explicitly not in charge of (t)his project any longer!
>>
>> As one of the founders and an active member of the PyPy
>> project, I was very happy to be invited to work on Psyco
>> V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
>> approach "an extension module that just makes Python faster".
>>
>> Psyco is a just-in-time compiler that accelerates arbitrary
>> Python code by specialization. We believe that Psyco's approach
>> can be carried out much further than it was tried so far, when
>> it's first version was abandoned.
>>
>> This first V2 release is source-only. There is no web-site, yet,
>> and there are no binaries for download. These will be available
>> in a few days onhttp://www.psyco.org.
>>
>> For the time being, please stick with subversion access,
>> building the extension module from source code. The repository
>> is here:
>>
>>      http://codespeak.net/svn/psyco/v2/dist
>>
>> Check-out the repository, and run the setup.py script,
>> given that you have access to a C compiler.
>>
>> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
>> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
>> is well being considered.
>>
>> The current improvements are, shortly:
>>
>>    - Support for Python 2.4, 2.5 and 2.6
>>    - a lot of new builtins
>>    - generators, fast and fully supported.
>>
>> More information is coming soon onhttp://www.psyco.org.
>>
>> This is the beginning of a series of new Psyco versions.
>> Many more improvements are prepared and about to be published,
>> soon, starting with the current version 2.0.0 .
>>
>> Stay tuned, this is just the beginning of psyco's re-birth!
>>
>> For questions about Psyco V2, please join the mailing list
>>
>>      psyco-de... at lists.sourceforge.net
>>
>> or contact me on IRC:
>>
>>      #psyco on irc.freenode.net .
>>
>> Psyco V2 is fundamentally supported by FATTOC, LLC.
>> Seehttp://www.fattoc.com.
>>
>> Without their continuous support, this work would not have
>> been possible at all. I wish to express my deepest thanks
>> to FATTOC, for allowing me to continue on Psyco with all the
>> energy that this ambitious project needs, and will need.
>>
>> Further special thanks are going to
>> Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
>> Raymond Hettinger, Fabrizio Milo, Michael Foord,
>> Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
>> for all the support and discussions.
>>
>> Looking forward to a great future of Psyco!
>>
>> July 17, 2009
>> --
>> Christian Tismer             :^)   <mailto:tis... at stackless.com>
>> tismerysoft GmbH             :     Have a break! Take a ride on  
>> Python's
>> Johannes-Niemeyer-Weg 9A     :    *Starship*http://starship.python.net/
>> 14109 Berlin                 :     PGP key ->http://wwwkeys.pgp.net/
>> work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
>> PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3  
>> BF04
>>        whom do you want to sponsor today?  http://www.stackless.com/
>
> congrats!
>
> btw is psyco.org owned?
> -- 
> http://mail.python.org/mailman/listinfo/python-list


From amrita at iisermohali.ac.in  Sat Jul 18 03:09:21 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 18 Jul 2009 12:39:21 +0530 (IST)
Subject: how two join and arrange two files together
Message-ID: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>


Hi,

I have two files having entries like:--
fileA
8  ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98	C = 179.39
15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C = 177.18
23 ALA H = 8.78	N = 120.16 CA = 55.84 HA = 4.14	C = 179.93
and
fileB
ChainA: ALA8	-67.217297	-37.131330
ChainA: ALA21	-69.822977	-48.871282
ChainA: ALA23	-59.148095	-46.540043
ChainA: ALA33	-65.459303	-43.269718

i want to join thses two files in such a way that the output file will
contain column of both the files and the enties of similar position of ALA
will be together.so the output file should look something like:----
fileC
8  ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98	C = 179.39 ChainA:
ALA8	-67.217297	-37.131330
15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C = 177.18
                                                           ChainA:
ALA21	-69.822977	-48.871282
23 ALA H = 8.78	N = 120.16 CA = 55.84 HA = 4.14	C = 179.93 ChainA:
ALA23	-59.148095	-46.540043
                                                           ChainA:
ALA33	-65.459303	-43.269718



Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From kalyanchakravarthy at hyit.com  Sat Jul 18 03:14:23 2009
From: kalyanchakravarthy at hyit.com (Kalyan Chakravarthy)
Date: Sat, 18 Jul 2009 12:44:23 +0530
Subject: Python import Error
Message-ID: <8ca278430907180014k460f3798mafef6fc59379677b@mail.gmail.com>

Hi All,
                   I am using* Python 2.6, MySQL 4.0* , I have successfully
Instaled MySQLdb (*MySQL-python-1.2.3c1.win32-py2.6*) in my system. I tested
through command prompt with "import MySQLdb ", its not shwing any errors
(means its instaled successfully), I set Eneceranment variable for Python

I  am running simple application with import "MySQLdb" to get the connection
to MySQL, But its throwing "No module named MySQLdb", Please any one tell me
what couled be the reasion

is there any version miss match with python and MySQL ?

Since last 3days I am strugling on this

-- 
Regards
Kalyan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/d1108ce1/attachment-0001.html>

From clp2 at rebertia.com  Sat Jul 18 03:19:23 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 00:19:23 -0700
Subject: how two join and arrange two files together
In-Reply-To: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>

On Sat, Jul 18, 2009 at 12:09 AM, <amrita at iisermohali.ac.in> wrote:
>
> Hi,
>
> I have two files having entries like:--
> fileA
> 8 ?ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93
> and
> fileB
> ChainA: ALA8 ? ?-67.217297 ? ? ?-37.131330
> ChainA: ALA21 ? -69.822977 ? ? ?-48.871282
> ChainA: ALA23 ? -59.148095 ? ? ?-46.540043
> ChainA: ALA33 ? -65.459303 ? ? ?-43.269718
>
> i want to join thses two files in such a way that the output file will
> contain column of both the files and the enties of similar position of ALA
> will be together.so the output file should look something like:----
> fileC
> 8 ?ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39 ChainA:
> ALA8 ? ?-67.217297 ? ? ?-37.131330
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ChainA:
> ALA21 ? -69.822977 ? ? ?-48.871282
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93 ChainA:
> ALA23 ? -59.148095 ? ? ?-46.540043
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ChainA:
> ALA33 ? -65.459303 ? ? ?-43.269718

This mailinglist is not a collection of free code monkeys. Show us
you've at least /tried/ to write this yourself, and tell us where
you're running into problems or what error you're getting.

See also http://catb.org/esr/faqs/smart-questions.html

Additionally, you might consider asking on the Indian Python
mailinglist instead:
http://mail.python.org/mailman/listinfo/bangpypers

- Chris


From amrita at iisermohali.ac.in  Sat Jul 18 03:39:09 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 18 Jul 2009 13:09:09 +0530 (IST)
Subject: how two join and arrange two files together
In-Reply-To: <50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
Message-ID: <23421.210.212.36.65.1247902749.squirrel@www.iisermohali.ac.in>

I tried to join these two files together using command.......

from itertools import izip
from os.path import exists

def parafiles(*files):
    vec = (open(f) for f in files if exists(f))
    data = izip(*vec)
    [f.close() for f in vec]
    return data

for data in parafiles('/home/amrita/alachems/chem1.txt',
'/home/amrita/secstr/secstr.txt'):
    print ' '.join(d.strip() for d in data)

it just joined the column of two files.

> On Sat, Jul 18, 2009 at 12:09 AM, <amrita at iisermohali.ac.in> wrote:
>>
>> Hi,
>>
>> I have two files having entries like:--
>> fileA
>> 8 ??ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39
>> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
>> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93
>> and
>> fileB
>> ChainA: ALA8 ?? ??-67.217297 ?? ?? ??-37.131330
>> ChainA: ALA21 ?? -69.822977 ?? ?? ??-48.871282
>> ChainA: ALA23 ?? -59.148095 ?? ?? ??-46.540043
>> ChainA: ALA33 ?? -65.459303 ?? ?? ??-43.269718
>>
>> i want to join thses two files in such a way that the output file will
>> contain column of both the files and the enties of similar position of
>> ALA
>> will be together.so the output file should look something like:----
>> fileC
>> 8 ??ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98 C = 179.39 ChainA:
>> ALA8 ?? ??-67.217297 ?? ?? ??-37.131330
>> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
>> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ??
>> ?? ?? ?? ?? ?? ChainA:
>> ALA21 ?? -69.822977 ?? ?? ??-48.871282
>> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93 ChainA:
>> ALA23 ?? -59.148095 ?? ?? ??-46.540043
>> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ??
>> ?? ?? ?? ?? ?? ChainA:
>> ALA33 ?? -65.459303 ?? ?? ??-43.269718
>
> This mailinglist is not a collection of free code monkeys. Show us
> you've at least /tried/ to write this yourself, and tell us where
> you're running into problems or what error you're getting.
>
> See also http://catb.org/esr/faqs/smart-questions.html
>
> Additionally, you might consider asking on the Indian Python
> mailinglist instead:
> http://mail.python.org/mailman/listinfo/bangpypers
>
> - Chris
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From __peter__ at web.de  Sat Jul 18 05:17:33 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 11:17:33 +0200
Subject: how two join and arrange two files together
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
Message-ID: <h3s3uu$8pk$00$1@news.t-online.com>

amrita at iisermohali.ac.in wrote:

> I tried to join these two files together using command.......
> 
> from itertools import izip
> from os.path import exists
> 
> def parafiles(*files):
>     vec = (open(f) for f in files if exists(f))
>     data = izip(*vec)
>     [f.close() for f in vec]
>     return data
> 
> for data in parafiles('/home/amrita/alachems/chem1.txt',
> '/home/amrita/secstr/secstr.txt'):
>     print ' '.join(d.strip() for d in data)

parafiles has a bug: vec is a generator and hence cannot be run twice. 
Therefore the odd [f.close()...] list comprehension (don't use a list comp 
if you don't care about the result!) has no effect. 

If you change vec into a list you will be hit by another problem -- the for 
loop trying to operate on closed files. While the correct approach probably 
involves a contextlib.contextmanager I recommend that you concentrate on 
your real problem and keep parafiles() simple:

def parafiles(*files):
    open_files = (open(f) for f in files if exits(f))
    return izip(*open_files)

> it just joined the column of two files.

Can you make an effort to express clearly what you want, preferrably with a 
simple and unambiguous example?

Please keep the line widths below the threshold of 78 characters to avoid 
messing it up on its way to the reader.

Peter



From amrita at iisermohali.ac.in  Sat Jul 18 05:29:28 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Sat, 18 Jul 2009 14:59:28 +0530 (IST)
Subject: how two join and arrange two files together
In-Reply-To: <h3s3uu$8pk$00$1@news.t-online.com>
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
	<h3s3uu$8pk$00$1@news.t-online.com>
Message-ID: <2569.210.212.36.65.1247909368.squirrel@www.iisermohali.ac.in>

I want to join column of two different data file but i want that the
entries will match (example i mentioned in my first mail, the position of
ALA eill match) if its not matching then it will get printed as such.

> amrita at iisermohali.ac.in wrote:
>
>> I tried to join these two files together using command.......
>>
>> from itertools import izip
>> from os.path import exists
>>
>> def parafiles(*files):
>>     vec = (open(f) for f in files if exists(f))
>>     data = izip(*vec)
>>     [f.close() for f in vec]
>>     return data
>>
>> for data in parafiles('/home/amrita/alachems/chem1.txt',
>> '/home/amrita/secstr/secstr.txt'):
>>     print ' '.join(d.strip() for d in data)
>
> parafiles has a bug: vec is a generator and hence cannot be run twice.
> Therefore the odd [f.close()...] list comprehension (don't use a list comp
> if you don't care about the result!) has no effect.
>
> If you change vec into a list you will be hit by another problem -- the
> for
> loop trying to operate on closed files. While the correct approach
> probably
> involves a contextlib.contextmanager I recommend that you concentrate on
> your real problem and keep parafiles() simple:
>
> def parafiles(*files):
>     open_files = (open(f) for f in files if exits(f))
>     return izip(*open_files)
>
>> it just joined the column of two files.
>
> Can you make an effort to express clearly what you want, preferrably with
> a
> simple and unambiguous example?
>
> Please keep the line widths below the threshold of 78 characters to avoid
> messing it up on its way to the reader.
>
> Peter
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From dickinsm at gmail.com  Sat Jul 18 05:50:06 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Sat, 18 Jul 2009 02:50:06 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org> 
	<057cc5d0-cbf4-4f13-b57c-406d36ce2649@k1g2000yqf.googlegroups.com> 
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com> 
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org> 
	<87fxcxj54d.fsf@busola.homelinux.net> <4A5E1538.7030107@sequans.com> 
	<ACF43DD8-8590-4AA2-8075-EFFEEF6481B9@umich.edu>
	<mailman.3186.1247684729.8015.python-list@python.org> 
	<pan.2009.07.15.23.01.37.844000@nowhere.com>
	<4A5EEDAE.3040605@sequans.com> 
	<mailman.3216.1247751117.8015.python-list@python.org>
	<HpWdnZReXqXvrsLXnZ2dnUVZ_qWdnZ2d@posted.visi> 
	<h3nk10$tvu$1@ger.gmane.org> <4A5F5759.4010600@sequans.com> 
	<1247774222.4a5f860ec3cfa@mail.uh.cu>
	<mailman.3268.1247828799.8015.python-list@python.org>
Message-ID: <9a623957-aece-413f-817a-88c76b9e25f4@y17g2000yqn.googlegroups.com>

On Jul 17, 12:06?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> I was saying that using boolean operators with object instead of boolean
> values is error prone,

I agree with this to some extent.  After all, Python conditional
expressions were eventually introduced in response to buggy uses of
the 'a and b or c' idiom.  See PEP 308, and:

http://mail.python.org/pipermail/python-dev/2005-September/056546.html

In my own code, I'm finding myself increasingly using conditional
expressions where I would once have used 'and' or 'or':

daysInAdvance = int(inputVar) if inputVar is not None else 0

--
Mark


From markbak at gmail.com  Sat Jul 18 06:21:57 2009
From: markbak at gmail.com (Mark Bakker)
Date: Sat, 18 Jul 2009 12:21:57 +0200
Subject: difference in printing to screen Mac / Windows
Message-ID: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com>

Hello list

I notice a difference between running the following script on my Mac and on
a PC:

from time import sleep
for i in range(10):
   print i,
   sleep(2)

On my PC this prints a number every 2 seconds. This is the behavior I want.

On my Mac Python waits 10*2 = 20 seconds, and then prints 0 1 2 3 4 5 6 7 8
9

Any thoughts on how I can make Python behave to get the Python behavior of
my PC on my Mac?

Thanks,

Mark
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/1cfdfa7f/attachment-0001.html>

From __peter__ at web.de  Sat Jul 18 06:40:01 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 12:40:01 +0200
Subject: how two join and arrange two files together
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
	<h3s3uu$8pk$00$1@news.t-online.com>
	<mailman.3352.1247909380.8015.python-list@python.org>
Message-ID: <h3s8pj$j92$00$1@news.t-online.com>

amrita at iisermohali.ac.in wrote:

>> Can you make an effort to express clearly what you want, preferrably with
>> a simple and unambiguous example?

> I want to join column of two different data file but i want that the
> entries will match (example i mentioned in my first mail, the position of
> ALA eill match) if its not matching then it will get printed as such.

Just say "No" if you mean it.

My best guess:

from collections import defaultdict

def merge(sources):
    blanks = [blank for items, blank, keyfunc in sources]
    d = defaultdict(lambda: blanks[:])
    for index, (items, blank, keyfunc) in enumerate(sources):
        for item in items:
            d[keyfunc(item)][index] = item
    for key in sorted(d):
        yield d[key]

if __name__ == "__main__":
    from StringIO import StringIO
    a = StringIO("""\
a alpha
c beta
d gamma
""")

    b = StringIO("""\
a one
b two
d three
e four
""")

    c = StringIO("""\
a 111
b 222
f 333
""")

    def key(line):
        return line[:1]
    def source(stream, blank="", key=key):
        return (line.strip() for line in stream), blank, key
    for m in merge([source(x) for x in [a,b,c]]):
        print "|".join(c.ljust(10) for c in m)





From python.list at tim.thechases.com  Sat Jul 18 07:03:11 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Sat, 18 Jul 2009 06:03:11 -0500
Subject: difference in printing to screen Mac / Windows
In-Reply-To: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com>
References: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com>
Message-ID: <4A61ABEF.6020002@tim.thechases.com>

> I notice a difference between running the following script on my Mac and on
> a PC:
> 
> from time import sleep
> for i in range(10):
>    print i,
>    sleep(2)
> 
> On my PC this prints a number every 2 seconds. This is the behavior I want.
> 
> On my Mac Python waits 10*2 = 20 seconds, and then prints 0 1 2 3 4 5 6 7 8
> 9

This sounds like a buffered vs. non-buffered output issue.  My 
guess would be that if you increased 10 to something larger, the 
output buffer would flush at various intervals.  The solution on 
the Mac (or other *nix-like OSes) would be to either start python 
in unbuffered mode:

   python -u mycode.py

Alternatively, you can force a flush of the output buffer at each 
iteration:

   import sys
   for i in range(10):
     print i
     sys.stdout.flush()
     sleep(2)

Lastly, you can force all standard-output in your program to be 
unbuffered without the "-u" parameter:

   sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)

Hope this helps,

-tkc




From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 07:21:32 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 12:21:32 +0100
Subject: Python graphics / imaging library
Message-ID: <sqn8j6xnm3.ln2@phoenix.fire>

Chaps,

what's the most appropriate (maintained) graphics library to use?  PIL seems
to have last been updated in 2006 http://www.pythonware.com/products/pil/
and GD seems to be even older.  Don't want to go down a dead end.

Pete

-- 
http://www.petezilla.co.uk


From motoom at xs4all.nl  Sat Jul 18 07:38:14 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Sat, 18 Jul 2009 13:38:14 +0200
Subject: Python graphics / imaging library
In-Reply-To: <sqn8j6xnm3.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>
Message-ID: <4A61B426.2090404@xs4all.nl>

Peter Chant wrote:

> what's the most appropriate (maintained) graphics library to use?  PIL seems
> to have last been updated in 2006 http://www.pythonware.com/products/pil/
> and GD seems to be even older.  Don't want to go down a dead end.

Contrary to organic material, software doesn't rot when it gets older.

PIL is pretty complete for the task it was designed to do, pretty 
debugged during the past years, and pretty much 'finished' -- it doesn't 
need frequent updates anymore.

Greetings,

-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 07:50:01 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 12:50:01 +0100
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
Message-ID: <9gp8j6xuh6.ln2@phoenix.fire>

Michiel Overtoom wrote:

> Peter Chant wrote:
> 
>> what's the most appropriate (maintained) graphics library to use?  PIL
>> seems to have last been updated in 2006
>> http://www.pythonware.com/products/pil/
>> and GD seems to be even older.  Don't want to go down a dead end.
> 
> Contrary to organic material, software doesn't rot when it gets older.
> 
> PIL is pretty complete for the task it was designed to do, pretty
> debugged during the past years, and pretty much 'finished' -- it doesn't
> need frequent updates anymore.
> 
> Greetings,
> 

No, it does not.  However, if PIL was updated last in 2006.  Python in 2009
has gone to version 3.1.  If PIL is compatible with 3.1 then I'm fine.  But
I don't want to have to stick with Python 2.5 as the rest of the world
moves on.

Pete


-- 
http://www.petezilla.co.uk


From benjamin.kaplan at case.edu  Sat Jul 18 08:26:22 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Sat, 18 Jul 2009 08:26:22 -0400
Subject: Python graphics / imaging library
In-Reply-To: <9gp8j6xuh6.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
Message-ID: <ec96e1390907180526y1d992820td83df38f41baaba7@mail.gmail.com>

On Sat, Jul 18, 2009 at 7:50 AM, Peter Chant <
REMpeteOVE at cappetezilla.italsco.uk> wrote:

> Michiel Overtoom wrote:
>
> > Peter Chant wrote:
> >
> >> what's the most appropriate (maintained) graphics library to use?  PIL
> >> seems to have last been updated in 2006
> >> http://www.pythonware.com/products/pil/
> >> and GD seems to be even older.  Don't want to go down a dead end.
> >
> > Contrary to organic material, software doesn't rot when it gets older.
> >
> > PIL is pretty complete for the task it was designed to do, pretty
> > debugged during the past years, and pretty much 'finished' -- it doesn't
> > need frequent updates anymore.
> >
> > Greetings,
> >
>
> No, it does not.  However, if PIL was updated last in 2006.  Python in 2009
> has gone to version 3.1.  If PIL is compatible with 3.1 then I'm fine.  But
> I don't want to have to stick with Python 2.5 as the rest of the world
> moves on.
>

The rest of the world hasn't moved on yet. Most people are still using
Python 2.6 and the 2.x series will continue to be actively developed for
another couple years.


> Pete
>
>
> --
> http://www.petezilla.co.uk
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090718/325c1520/attachment-0001.html>

From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 08:30:02 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 13:30:02 +0100
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
Message-ID: <arr8j6xn0c.ln2@phoenix.fire>

Peter Chant wrote:


> 
> No, it does not.  However, if PIL was updated last in 2006.  Python in
> 2009
> has gone to version 3.1.  If PIL is compatible with 3.1 then I'm fine. 
> But I don't want to have to stick with Python 2.5 as the rest of the world
> moves on.

BTW, this was not a critisism of PIL or GD, rather what do people generally
use now?

-- 
http://www.petezilla.co.uk


From motoom at xs4all.nl  Sat Jul 18 08:41:36 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Sat, 18 Jul 2009 14:41:36 +0200
Subject: Python graphics / imaging library
In-Reply-To: <arr8j6xn0c.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>	<mailman.3355.1247917094.8015.python-list@python.org>	<9gp8j6xuh6.ln2@phoenix.fire>
	<arr8j6xn0c.ln2@phoenix.fire>
Message-ID: <4A61C300.9070503@xs4all.nl>

Peter Chant wrote:

> what do people generally use now?

I can only speak for myself... I use PIL ;-)

Greetings,



From maxerickson at gmail.com  Sat Jul 18 08:54:50 2009
From: maxerickson at gmail.com (Max Erickson)
Date: Sat, 18 Jul 2009 12:54:50 +0000 (UTC)
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
Message-ID: <Xns9C4C5AA8CF713maxericksongmailcom@80.91.229.13>

Peter Chant <REMpeteOVE at CAPpetezilla.ITALSco.uk> wrote:

> No, it does not.  However, if PIL was updated last in 2006. 
> Python in 2009 has gone to version 3.1.  If PIL is compatible
> with 3.1 then I'm fine.  But I don't want to have to stick with
> Python 2.5 as the rest of the world moves on.
> 
> Pete
> 
> 

Various messages to the Image-SIG mailing list indicate that support 
for 3.x is coming after a release of 1.1.7:

http://mail.python.org/pipermail/image-sig/2009-March/005498.html

More here:

http://mail.python.org/pipermail/image-sig/2009-March/thread.html

More recent months contain updates to the status of 1.1.7, it is 
headed towards a release. Preliminary tarballs and binaries are 
available on effbot.org:

http://effbot.org/downloads/#imaging
http://effbot.org/downloads/#pil


max



From rhodri at wildebst.demon.co.uk  Sat Jul 18 09:17:12 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sat, 18 Jul 2009 14:17:12 +0100
Subject: Beginners question
In-Reply-To: <4A612D74.80908@gmail.com>
References: <9c8c445f0907171842p2b1ee910y3338450881ac7ad2@mail.gmail.com>
	<4A612D74.80908@gmail.com>
Message-ID: <op.uw9luyxka8ncjz@gnudebst>

On Sat, 18 Jul 2009 03:03:32 +0100, gabrielmonnerat  
<gabrielmonnerat at gmail.com> wrote:

> Ronn Ross wrote:
>> How do you define a global variable in a class. I tried this with do  
>> success:
>> class ClassName:
>>     global_var = 1
>>        def some_methos():
>>         print global_var
>>
>> This doesn't work. What am I doing wrong?
> You need pass "self" to the function and "global_var" needs be called  
> with self.
>
> class ClassName:
>     global_var = 1
>        def some_methos(self):
>         print self.global_var

If the OP really wants global_var to be global to the class, this
approach will only work as long as he never assigns to self.global_var.

The terminology is a bit confusing here.  "Global variables" refers to
variables which are global to an entire module, ones that you would
use "global" to declare inside a function.  Something like this:

x = 5
def set_x(y):
     global x
     x = y

set_x(3)
print x

...gives the result "3"

The idea of defining a global variable in a class is a bit of a
nonsense, since globals exist for the entire module.  There are,
however, variables that exist and are the same for every instance
of a class, or "class attributes" as they are normally called.  You
use them either by assignment in the class definition, or in a
method by prefixing them with the class name.

class ClassName:
     global_var = 1
     def some_method(self):
         print ClassName.global_var
         ClassName.global_var = 2

"Instance attributes", the ones prefixed by "self", are what get
used for most purposes.  These are separate for each different
instance of the class.

class ClassName:
     def __init__(self, val):
        self.var = val

a = ClassName(1)
b = ClassName(2)

print a.var, b.var

...gives the result "1 2"

The wrinkle is that if you read from an instance attribute that
doesn't exist, Python will use a class attribute of the same name
if there is one.  This is often exploited for setting default
values.  Beware, though: the moment you assign, an instance
attribute is created -- the underlying class attribute is *not*
changed.

class ClassName:
     global_var = 1
     def some_method(self):
         self.global_var = 2

a = ClassName()
b = ClassName()
b.some_method()
print a.global_var, b.global_var

...gives the result "1 2" again!

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From dstanek at dstanek.com  Sat Jul 18 09:41:13 2009
From: dstanek at dstanek.com (David Stanek)
Date: Sat, 18 Jul 2009 09:41:13 -0400
Subject: Python import Error
In-Reply-To: <8ca278430907180014k460f3798mafef6fc59379677b@mail.gmail.com>
References: <8ca278430907180014k460f3798mafef6fc59379677b@mail.gmail.com>
Message-ID: <de32cc030907180641l367f9406m36c5ce4ff0bf4ee@mail.gmail.com>

On Sat, Jul 18, 2009 at 3:14 AM, Kalyan
Chakravarthy<kalyanchakravarthy at hyit.com> wrote:
> Hi All,
> ?????????????????? I am using Python 2.6, MySQL 4.0 , I have successfully
> Instaled MySQLdb (MySQL-python-1.2.3c1.win32-py2.6) in my system. I tested
> through command prompt with "import MySQLdb ", its not shwing any errors
> (means its instaled successfully), I set Eneceranment variable for Python
>
> I? am running simple application with import "MySQLdb" to get the connection
> to MySQL, But its throwing "No module named MySQLdb", Please any one tell me
> what couled be the reasion
>
> is there any version miss match with python and MySQL ?
>
> Since last 3days I am strugling on this
>

Off the top of my head I would say that maybe you are using one python
binary from the command-line and another in your script or possibly
your python path is foobar.

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From tjcrone at gmail.com  Sat Jul 18 10:34:11 2009
From: tjcrone at gmail.com (Timothy Crone)
Date: Sat, 18 Jul 2009 10:34:11 -0400
Subject: Unpack Expects the Wrong Number of Bytes
Message-ID: <78926b920907180734p7363af24v7f81f425cdd6d972@mail.gmail.com>

Hello,

I have noticed that for certain format strings, struct.unpack expects
the wrong number of bytes. For example, this works fine

header = "4si4s4si2h2i3h4s"
data = list(unpack(header,f.read(42)))

however, this

header = "4si4s4si2h2i3h4si"
data = list(unpack(header,f.read(46)))

returns the following error:

struct.error: unpack requires a string argument of length 48

So even though my format string includes an additional 4-byte integer,
unpack is expecting 6 additional bytes. Here's a simpler example:

This works:

header = "s"
data = list(unpack(header,f.read(1)))

however this:

header = "si"
data = list(unpack(header,f.read(5)))

throws

struct.error: unpack requires a string argument of length 8

So unpack expects 7 additional bytes when an integer is added to the
format string. Does anyone know what is going on? I am using Debian
stable, so my Python version is 2.5.2. But I have replicated this with
2.6.2. Here's my proc/version: Linux version 2.6.30-bpo.1-amd64
(Debian 2.6.30-1~bpo50+1) (nobse at debian.org) (gcc version 4.3.2
(Debian 4.3.2-1.1) ) #1 SMP Fri Jun 26 09:41:55 UTC 2009

Any help would be greatly appreciated.

Cheers,
Tim


From aahz at pythoncraft.com  Sat Jul 18 10:44:29 2009
From: aahz at pythoncraft.com (Aahz)
Date: 18 Jul 2009 07:44:29 -0700
Subject: setup.py not found
References: <3be2bdce-680d-4b32-ad0c-ef46caf556e9@f10g2000vbf.googlegroups.com>
Message-ID: <h3sn4d$fc3$1@panix3.panix.com>

In article <3be2bdce-680d-4b32-ad0c-ef46caf556e9 at f10g2000vbf.googlegroups.com>,
Larry.Martell at gmail.com <Larry.Martell at gmail.com> wrote:
>
>I'm trying to install a package (cx_Oracle) on a mac running 10.5.7.
>I've done this on other platforms, but never on a mac. I followed the
>instructions given, but when I try and run setup I get:
>
>Apollo:instantclient_10_2 user$ python setup.py build
>/System/Library/Frameworks/Python.framework/Versions/2.5/Resources/
>Python.app/Contents/MacOS/Python: can't open file 'setup.py': [Errno
>2] No such file or directory
>
>Is there something else I have to install first to have this?

Do you have a setup.py in the current working directory?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From sjmachin at lexicon.net  Sat Jul 18 10:47:15 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sat, 18 Jul 2009 07:47:15 -0700 (PDT)
Subject: Unpack Expects the Wrong Number of Bytes
References: <mailman.3364.1247927673.8015.python-list@python.org>
Message-ID: <34a7b901-4d33-469a-8b35-5ac1f30304fa@i18g2000pro.googlegroups.com>

On Jul 19, 12:34?am, Timothy Crone <tjcr... at gmail.com> wrote:
> Hello,
>
> I have noticed that for certain format strings, struct.unpack expects
> the wrong number of bytes.
[snip]
> header = "si"
> data = list(unpack(header,f.read(5)))
>
> throws
>
> struct.error: unpack requires a string argument of length 8
>
> So unpack expects 7 additional bytes when an integer is added to the
> format string. Does anyone know what is going on?

Alignment. 1 byte for the "s", 3 pad bytes to get to the next "i"
boundary, 4 bytes for the "i".

http://docs.python.org/library/struct.html
Then Ctrl-F search for "align"

Choose a prefix character whose MO matches the struct that you need to
work with.

Cheers,
John


From python at mrabarnett.plus.com  Sat Jul 18 10:53:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 18 Jul 2009 15:53:18 +0100
Subject: Try... except....Try again?
In-Reply-To: <2d56febf0907171948l35e73c14gf02bc3c6ef11d493@mail.gmail.com>
References: <2d56febf0907162231s2134f32dm7d31727087a8b215@mail.gmail.com>	<mailman.3275.1247836630.8015.python-list@python.org>	<02707804$0$5185$c3e8da3@news.astraweb.com>	<2d56febf0907170734r21254251pc62a70601cf8f043@mail.gmail.com>	<2d56febf0907170735k6e123cd9n16727acacc3b046a@mail.gmail.com>	<h3qs5u$1cr$1@ger.gmane.org>	<2d56febf0907171507y75f6436ete75cb3f748ee838d@mail.gmail.com>	<4A611D89.7040603@ieee.org>	<2d56febf0907171947s6a4a010fp124146d54d560bf4@mail.gmail.com>
	<2d56febf0907171948l35e73c14gf02bc3c6ef11d493@mail.gmail.com>
Message-ID: <4A61E1DE.8010300@mrabarnett.plus.com>

Xavier Ho wrote:
> Darn it.
> 
> On Sat, Jul 18, 2009 at 8:55 AM, Dave Angel <davea at ieee.org 
> <mailto:davea at ieee.org>> wrote:
> 
> 
>     You don't need a counter.  len() will tell you the size of the list
>     of primes.
> 
> 
> Does len() go through and count by itself, or does it actually keep 
> track of the size and just return the memory? I always thought it would 
> go through and count, which may take some time. I could be wrong. 
> 
[snip]
Lists (and strings, tuples, dicts and sets) know how many items they
contain.


From rridge at csclub.uwaterloo.ca  Sat Jul 18 10:55:53 2009
From: rridge at csclub.uwaterloo.ca (Ross Ridge)
Date: Sat, 18 Jul 2009 10:55:53 -0400
Subject: Unpack Expects the Wrong Number of Bytes
References: <mailman.3364.1247927673.8015.python-list@python.org>
Message-ID: <h3snpp$ug6$1@rumours.uwaterloo.ca>

Timothy Crone  <tjcrone at gmail.com> wrote:
>header = "s"
>data = list(unpack(header,f.read(1)))
>
>however this:
>
>header = "si"
>data = list(unpack(header,f.read(5)))
>
>throws
>
>struct.error: unpack requires a string argument of length 8
>
>So unpack expects 7 additional bytes when an integer is added to the
>format string. Does anyone know what is going on?

It's adding pad bytes so that the format matches the equivilent C
structure on your machine.  You should use either the "<" little-endian
or the ">" big-endian prefix depending on the byte order used in the file
you're trying to unpack.  You can also use the "=" native byte-order
flag if endianness of the file format changes according to the machine
your Python program runs on.  If you use any of these flags, no extra
padding will be inserted.

				Ross Ridge

-- 
 l/  //	  Ross Ridge -- The Great HTMU
[oo][oo]  rridge at csclub.uwaterloo.ca
-()-/()/  http://www.csclub.uwaterloo.ca/~rridge/ 
 db  //	  


From alan.isaac at gmail.com  Sat Jul 18 11:31:46 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sat, 18 Jul 2009 15:31:46 GMT
Subject: invoke method on many instances
In-Reply-To: <02701d35$0$5185$c3e8da3@news.astraweb.com>
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <CVl8m.141$MA3.16@nwrddc02.gnilink.net>

> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>> def apply2(itr, methodname, *args, **kwargs):
>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>     for item in itr:
>>         f(item)


On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
> for obj in objects:
>     getattr(obj, methodname)(*args, **kwargs)


Are there any obvious considerations in choosing
between those two?



> See also these recipes from the "Python Cookbook": 
> http://code.activestate.com/recipes/52289/
> http://code.activestate.com/recipes/87370/

Interesting.

Thanks,
Alan


From REMpeteOVE at CAPpetezilla.ITALSco.uk  Sat Jul 18 11:41:33 2009
From: REMpeteOVE at CAPpetezilla.ITALSco.uk (Peter Chant)
Date: Sat, 18 Jul 2009 16:41:33 +0100
Subject: Python graphics / imaging library
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
	<mailman.3361.1247921706.8015.python-list@python.org>
Message-ID: <d279j6x8r6.ln2@phoenix.fire>

Max Erickson wrote:

> More recent months contain updates to the status of 1.1.7, it is
> headed towards a release. Preliminary tarballs and binaries are
> available on effbot.org:
> 
> http://effbot.org/downloads/#imaging
> http://effbot.org/downloads/#pil

Excellent.  From a very brief look it seems like it will be quite simple to
use.

Pete


-- 
http://www.petezilla.co.uk


From tkermode at gmail.com  Sat Jul 18 11:50:44 2009
From: tkermode at gmail.com (Tom Kermode)
Date: Sat, 18 Jul 2009 16:50:44 +0100
Subject: A Bug By Any Other Name ...
In-Reply-To: <h2rnoe$26s$5@lust.ihug.co.nz>
References: <h2rnoe$26s$5@lust.ihug.co.nz>
Message-ID: <da7092380907180850l5e2f62b8ic355463a8e2e5d9d@mail.gmail.com>

Maybe the IDE is the best place to warn you of something like that.

You could have an IDE where you specify which language you're more
familiar with and then have it display warnings likely to be relevant
to you.  People could collaborate to add support for gradually more
niche languages.

Python could continue to work the way it was designed to and people
documenting python wouldn't have to worry about this kind of issue. :)

2009/7/6 Lawrence D'Oliveiro <ldo at geek-central.gen.new_zealand>:
> I wonder how many people have been tripped up by the fact that
>
> ? ?++n
>
> and
>
> ? ?--n
>
> fail silently for numeric-valued n.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.kiloday.com
http://www.fourstopspast.com


From marcusw at cox.net  Sat Jul 18 11:58:47 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 18 Jul 2009 11:58:47 -0400
Subject: Python graphics / imaging library
In-Reply-To: <d279j6x8r6.ln2@phoenix.fire>
References: <sqn8j6xnm3.ln2@phoenix.fire>
	<mailman.3355.1247917094.8015.python-list@python.org>
	<9gp8j6xuh6.ln2@phoenix.fire>
	<mailman.3361.1247921706.8015.python-list@python.org>
	<d279j6x8r6.ln2@phoenix.fire>
Message-ID: <h3srfn$h23$1@adenine.netfront.net>

On 7/18/2009 11:41 AM, Peter Chant wrote:
> Max Erickson wrote:
> 
>> More recent months contain updates to the status of 1.1.7, it is
>> headed towards a release. Preliminary tarballs and binaries are
>> available on effbot.org:
>>
>> http://effbot.org/downloads/#imaging
>> http://effbot.org/downloads/#pil
> 
> Excellent.  From a very brief look it seems like it will be quite simple to
> use.
> 
> Pete
> 
> 
Yes, it was fun to work with (for me at least).

Marcus


From gnarlodious at gmail.com  Sat Jul 18 12:32:18 2009
From: gnarlodious at gmail.com (Gnarlodious)
Date: Sat, 18 Jul 2009 09:32:18 -0700 (PDT)
Subject: Rus Python script interactively
Message-ID: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>

In an interactive session (I am using iPython), what is the most
elegant way to run a Python script from Terminal? Right now I am
saying:

import subprocess
subprocess.call("python /path/to/scriptname.py", shell=True)

But I am calling a shell process and I'd rather not. The script just
runs, no inputs are needed. Is there a more Pythonesque method?

-- Gnarlie
http://Gnarlodious.com/


From deets at nospam.web.de  Sat Jul 18 12:39:53 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 18 Jul 2009 18:39:53 +0200
Subject: Rus Python script interactively
In-Reply-To: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <7cec6pF26munvU1@mid.uni-berlin.de>

Gnarlodious schrieb:
> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?

If it's in the path, you can just import it. That will of course only be 
possible once per ipython-session.

Diez


From lie.1296 at gmail.com  Sat Jul 18 12:55:49 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 19 Jul 2009 02:55:49 +1000
Subject: Rus Python script interactively
In-Reply-To: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <h3suqn$ifa$1@ger.gmane.org>

Gnarlodious wrote:
> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?
> 
> -- Gnarlie
> http://Gnarlodious.com/

IMHO, starting a new terminal and runs the script from there.
Or quitting/pausing the current interactive session and run it like
normal python scripts.

Alternatively, you may also want to look at `execfile` built-in function.
>>> execfile('myscript.py', {}, {})



From marcusw at cox.net  Sat Jul 18 13:04:07 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 18 Jul 2009 13:04:07 -0400
Subject: Rus Python script interactively
In-Reply-To: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <h3sva8$1kn3$1@adenine.netfront.net>

On 7/18/2009 12:32 PM, Gnarlodious wrote:
> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?
> 
> -- Gnarlie
> http://Gnarlodious.com/
You could put the code of the script in a main() function and have an if 
__name__ == '__main__': around the internal call. That way, it will 
still run the code if you run it normally, and you can also run it 
several times from the interactive session, ie:
file you want to run:
{{{
def somefunction():
	print 'hello world'

somefunction()
}}}
file after modifications:
{{{
def somefunction():
	print 'hello world'

def main():
	somefunction()

if __name__ == '__main__': #only true if the file is being run normally, 
not imported.
	main()
}}}
Both of those, if run normally, will print "hello world". If the first 
one is imported, it will run once and not me runnable in that session 
again. If the second one is imported, it will not do anything until you 
call the main() function, and then you can call it again as many times 
as you want:
{{{
 >>> import thefile
 >>> for i in range(5):
... 	thefile.main()
...
hello world
hello world
hello world
hello world
hello world
 >>> exit()
}}}
Hope this helps you!

Marcus


From __peter__ at web.de  Sat Jul 18 13:13:17 2009
From: __peter__ at web.de (Peter Otten)
Date: Sat, 18 Jul 2009 19:13:17 +0200
Subject: Rus Python script interactively
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
Message-ID: <h3svqt$e8s$02$1@news.t-online.com>

Gnarlodious wrote:

> In an interactive session (I am using iPython), what is the most
> elegant way to run a Python script from Terminal? Right now I am
> saying:
> 
> import subprocess
> subprocess.call("python /path/to/scriptname.py", shell=True)
> 
> But I am calling a shell process and I'd rather not. The script just
> runs, no inputs are needed. Is there a more Pythonesque method?

After a quick glance over ipython's %quickref:

In [1]: !mkdir -p path/to

In [2]: !echo 'print "works!"' > path/to/scriptname.py

In [3]: %run path/to/scriptname.py
works!




From timphotoman at gmail.com  Sat Jul 18 13:25:11 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 13:25:11 -0400
Subject: python command running old version
Message-ID: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>

My brain is running in n00b mode this morning...must find coffee.

I upgraded python this morning and entering python from the command
line runs the old version.

Just looked and it appears the old version is in /usr/bin while the
new one is in /usr/local/bin/

Besides changing the path order, how do I ensure it runs the new
version? I'm sure I'll bang my head on the desk in shame as soon as
I'm reminded.

Thanks.


From clp2 at rebertia.com  Sat Jul 18 13:26:40 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 10:26:40 -0700
Subject: python command running old version
In-Reply-To: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
Message-ID: <50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>

On Sat, Jul 18, 2009 at 10:25 AM, Tim Edwards<timphotoman at gmail.com> wrote:
> My brain is running in n00b mode this morning...must find coffee.
>
> I upgraded python this morning and entering python from the command
> line runs the old version.

Which OS? How did you install it?

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Sat Jul 18 13:32:25 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 10:32:25 -0700
Subject: Auto Send URL
In-Reply-To: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>
References: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>
Message-ID: <50697b2c0907181032x6f0029dfs304a345ca2835690@mail.gmail.com>

On Fri, Jul 17, 2009 at 6:02 AM, Victor Subervi<victorsubervi at gmail.com> wrote:
> Hi;
> I am trying to script code that automatically sends a Web site visitor to an
> URL. Specifically, when they enter a value in a search box, I have that form
> sent to a script that writes an URL acceptable to Google, then I want to
> send the visitor off without him having to click another button. How do I do
> this?

Send back a webpage with a Refresh meta tag:

<html>
    <head>
    <meta http-equiv="Refresh" content="0; url=http://YOUR-URL-HERE/">
    </head>
</html>

Cheers,
Chris
-- 
http://blog.rebertia.com


From lists at cheimes.de  Sat Jul 18 13:33:48 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sat, 18 Jul 2009 19:33:48 +0200
Subject: python command running old version
In-Reply-To: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
Message-ID: <h3t11s$nqe$1@ger.gmane.org>

Tim Edwards wrote:
> Besides changing the path order, how do I ensure it runs the new
> version? I'm sure I'll bang my head on the desk in shame as soon as
> I'm reminded.

hash -r

Christian



From timphotoman at gmail.com  Sat Jul 18 13:37:50 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 13:37:50 -0400
Subject: python command running old version
In-Reply-To: <50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
	<50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
Message-ID: <ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>

> Which OS? How did you install it?

Sorry (see I need that coffee)

Installed on redhat from source


From timphotoman at gmail.com  Sat Jul 18 13:54:31 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 13:54:31 -0400
Subject: python command running old version
In-Reply-To: <h3t11s$nqe$1@ger.gmane.org>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
	<h3t11s$nqe$1@ger.gmane.org>
Message-ID: <ad7b98710907181054q5cf8e045r5908252f5740a6ed@mail.gmail.com>

>> Besides changing the path order, how do I ensure it runs the new
>> version? I'm sure I'll bang my head on the desk in shame as soon as
>> I'm reminded.
>
> hash -r

Thanks.


From lie.1296 at gmail.com  Sat Jul 18 13:58:13 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 19 Jul 2009 03:58:13 +1000
Subject: python command running old version
In-Reply-To: <ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>	<50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
	<ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>
Message-ID: <h3t2fn$rhm$1@ger.gmane.org>

Tim Edwards wrote:
>> Which OS? How did you install it?
> 
> Sorry (see I need that coffee)
> 
> Installed on redhat from source

You should consult the distro's (i.e. RedHat's) documentation/mailing
list about changing the default python interpreter. In most cases, you
will need to make sure all python-related packages are compatible with
the new python version. In popular distros, there should be a script
that will do that for you.



From akhilanger at gmail.com  Sat Jul 18 14:20:20 2009
From: akhilanger at gmail.com (akhil1988)
Date: Sat, 18 Jul 2009 11:20:20 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <pan.2009.07.17.07.20.15.547000@nowhere.com>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<pan.2009.07.17.07.20.15.547000@nowhere.com>
Message-ID: <24550497.post@talk.nabble.com>


Thanks Nobody-38, it solved my problem immediately.

--Thanks Again,
Akhil

Nobody-38 wrote:
> 
> On Thu, 16 Jul 2009 20:26:39 -0700, akhil1988 wrote:
> 
>> Well, you were write: unintentionally I removed strip(). But the problem
>> does
>> not ends here:
>> 
>> I get this error now:
>> 
>>  File "./temp.py", line 488, in <module>
>>     main()
>>   File "./temp.py", line 475, in main
>>     for line in sys.stdin:
>>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>>     (result, consumed) = self._buffer_decode(data, self.errors, final)
>> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2:
>> invalid
>> data
>> 
>> for this line:
>> ?
> 
> Right. You're running in a locale whose encoding is UTF-8, but feeding
> data which isn't valid UTF-8 to stdin. If you want to use data with a
> different encoding, you need to replace sys.stdin, e.g.:
> 
> import sys
> import io
> sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding = 'iso-8859-1')
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24550497.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From akhilanger at gmail.com  Sat Jul 18 14:25:53 2009
From: akhilanger at gmail.com (akhil1988)
Date: Sat, 18 Jul 2009 11:25:53 -0700 (PDT)
Subject: UnicodeEncodeError: 'ascii' codec can't encode character
	u'\xb7' in position 13: ordinal not in range(128)
In-Reply-To: <gsKdncY9AMiQKP3XnZ2dnUVZ_hudnZ2d@pdx.net>
References: <24509879.post@talk.nabble.com>
	<50697b2c0907152139x13b501b0w24a6d84135923f61@mail.gmail.com>
	<24510222.post@talk.nabble.com>
	<4a5ed587$0$1627$742ec2ed@news.sonic.net>
	<63e1a8d1-b9ad-4275-95e6-54fad122fd05@l35g2000pra.googlegroups.com>
	<24522412.post@talk.nabble.com> <m2ws68th6f.fsf@cs.uu.nl>
	<pan.2009.07.17.01.21.48.641000@nowhere.com>
	<gsKdncY9AMiQKP3XnZ2dnUVZ_hudnZ2d@pdx.net>
Message-ID: <24550540.post@talk.nabble.com>


Thanks David, it solved my problem immediately. 

I will follow your advise from next time but honestly I am new to python
with not much knowledge about text formats. And the main portion of my
project was not to deal with these, so I just wanted to get this solved as I
was already struck at this for 2 days. If you think I am wrong in my
approach to getting problems solved, please let me know. Your advise would
be helpful in future for me.

--Thanks Again,
Akhil 

Scott David Daniels wrote:
> 
> akhil1988 wrote:
> <mis-ordered reply, bits shown below>>
>> Nobody-38 wrote:
>>> On Thu, 16 Jul 2009 15:43:37 -0700, akhil1988 wrote:
> ...
>>>>> In Python 3 you can't decode strings because they are Unicode strings
>>>>> and it doesn't make sense to decode a Unicode string. You can only
>>>>> decode encoded things which are byte strings. So you are mixing up
>>>>> byte
>>>>> strings and Unicode strings.
>>>> ... I read a byte string from sys.stdin which needs to converted to
>>>> unicode
>>>> string for further processing.
>>> In 3.x, sys.stdin (stdout, stderr) are text streams, which means that
>>> they
>>> read and write Unicode strings, not byte strings.
>>>
>>>> I cannot just remove the decode statement and proceed?
>>>> This is it what it looks like:
>>>>     for line in sys.stdin:
>>>>         line = line.decode('utf-8').strip()
>>>>         if line == '<page>': #do something here
>>>>         ....
>>>> If I remove the decode statement, line == '<page>' never gets true. 
>>> Did you inadvertently remove the strip() as well?
>> ... unintentionally I removed strip()....
>> I get this error now:
>>  File "./temp.py", line 488, in <module>
>>     main()
>>   File "./temp.py", line 475, in main
>>     for line in sys.stdin:
>>   File "/usr/local/lib/python3.1/codecs.py", line 300, in decode
>>     (result, consumed) = self._buffer_decode(data, self.errors, final)
>> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0-2:
>> invalid
>> data
> 
> (1) Do not top post.
> (2) Try to fully understand the problem and proposed solution, rather
>      than trying to get people to tell you just enough to get your code
>      going.
> (3) The only way sys.stdin can possibly return unicode is to do some
>      decoding of its own.  your job is to make sure it uses the correct
>      decoding.  So, if you know your source is always utf-8, try
>      something like:
> 
>      import sys
>      import io
> 
>      sys.stdin = io.TextIOWrapper(sys.stdin.detach(), encoding='utf8')
> 
>      for line in sys.stdin:
>          line = line.strip()
>          if line == '<page>':
>              #do something here
>          ....
> 
> --Scott David Daniels
> Scott.Daniels at Acm.Org
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/UnicodeEncodeError%3A-%27ascii%27-codec-can%27t-encode-character-u%27%5Cxb7%27-in-position-13%3A-ordinal-not-in-range%28128%29-tp24509879p24550540.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From timphotoman at gmail.com  Sat Jul 18 15:35:19 2009
From: timphotoman at gmail.com (Tim Edwards)
Date: Sat, 18 Jul 2009 15:35:19 -0400
Subject: python command running old version
In-Reply-To: <h3t2fn$rhm$1@ger.gmane.org>
References: <ad7b98710907181025p78678198s45366ae34d0f8aa3@mail.gmail.com>
	<50697b2c0907181026p2ad3fb44mba3570ed44e17aeb@mail.gmail.com>
	<ad7b98710907181037v4f38db6do53c6c520dc606731@mail.gmail.com>
	<h3t2fn$rhm$1@ger.gmane.org>
Message-ID: <ad7b98710907181235p4bd64c44j288c7642df4cad65@mail.gmail.com>

> You should consult the distro's (i.e. RedHat's) documentation/mailing
> list about changing the default python interpreter. In most cases, you
> will need to make sure all python-related packages are compatible with
> the new python version. In popular distros, there should be a script
> that will do that for you.

Thanks, I'll look into that.


From sgm at objexx.com  Sat Jul 18 16:49:42 2009
From: sgm at objexx.com (SK)
Date: Sat, 18 Jul 2009 13:49:42 -0700 (PDT)
Subject: multiprocessing and freezing on Windows
References: <20282f53-a848-4f44-bad7-c7d781294369@c36g2000yqn.googlegroups.com>
	<a205db1d-a801-4774-bfa1-124a723ea71b@p36g2000prn.googlegroups.com> 
	<mailman.2670.1246863247.8015.python-list@python.org>
Message-ID: <015ab41f-7433-4136-8b9c-809f96ae6384@o13g2000vbl.googlegroups.com>

Thanks Gabriel.

Posted as: http://bugs.python.org/issue6461

The multiprocessing author has tentatively confirmed the bug.


From twgray2007 at gmail.com  Sat Jul 18 17:33:48 2009
From: twgray2007 at gmail.com (twgray)
Date: Sat, 18 Jul 2009 14:33:48 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python socket?
Message-ID: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>

I am attempting to send a jpeg image file created on an embedded
device over a wifi socket to a Python client running on a Linux pc
(Ubuntu).  All works well, except I don't know, on the pc client side,
what the file size is?  The following is a snippet:

[code]
        f = open("frame.jpg",mode = 'wb')
       while True:
            data = self.s.recv(MAXPACKETLEN)
            if len(data) == 0:
                break
            recvd += len(data)
            f.write(data)
        f.close()
[end]

It appears to be locking up in  'data=self.s.recv(MAXPACKETLEN)' on
the final packet, which will always be less than MAXPACKETLEN.

I guess my question is, how do I detect end of data on the client side?


From irmen.NOSPAM at xs4all.nl  Sat Jul 18 17:43:47 2009
From: irmen.NOSPAM at xs4all.nl (Irmen de Jong)
Date: Sat, 18 Jul 2009 23:43:47 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
Message-ID: <4a624251$0$191$e4fe514c@news.xs4all.nl>

twgray wrote:
> I am attempting to send a jpeg image file created on an embedded
> device over a wifi socket to a Python client running on a Linux pc
> (Ubuntu).  All works well, except I don't know, on the pc client side,
> what the file size is?  

You don't. Sockets are just endless streams of bytes. You will have to design some form 
of 'wire protocol' that includes the length of the message that is to be read.
For instance a minimalistic protocol could be the following:
Send 4 bytes that contain the length (an int) then the data itself. The client reads 4 
bytes, decodes it into the integer that tells it the length, and then reads the correct 
amount of bytes from the socket.


--irmen


From gnarlodious at gmail.com  Sat Jul 18 17:48:24 2009
From: gnarlodious at gmail.com (Gnarlodious)
Date: Sat, 18 Jul 2009 14:48:24 -0700 (PDT)
Subject: Rus Python script interactively
References: <e9c0dce4-502a-42a3-8f8a-51110c92cc29@m11g2000yqh.googlegroups.com>
	<h3svqt$e8s$02$1@news.t-online.com>
Message-ID: <0814d92c-46bf-4421-88ea-499cb82a0be8@w41g2000yqb.googlegroups.com>

Thanks for all the suggestions! The last solution is the one I was
ooking for, I am really starting to like iPython. Learning all kinds
of new tricks!.

-- Gnarlie


From tycho at tycho.ws  Sat Jul 18 17:52:41 2009
From: tycho at tycho.ws (Tycho Andersen)
Date: Sat, 18 Jul 2009 16:52:41 -0500
Subject: How to receive a data file of unknown length using a python 
	socket?
In-Reply-To: <4a624251$0$191$e4fe514c@news.xs4all.nl>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
Message-ID: <49b3a7400907181452t3f87ee39n17b3dc15c3426d34@mail.gmail.com>

On Sat, Jul 18, 2009 at 4:43 PM, Irmen de Jong<irmen.NOSPAM at xs4all.nl> wrote:
> twgray wrote:
>>
>> I am attempting to send a jpeg image file created on an embedded
>> device over a wifi socket to a Python client running on a Linux pc
>> (Ubuntu). ?All works well, except I don't know, on the pc client side,
>> what the file size is?
>
> You don't. Sockets are just endless streams of bytes. You will have to
> design some form of 'wire protocol' that includes the length of the message
> that is to be read.
> For instance a minimalistic protocol could be the following:
> Send 4 bytes that contain the length (an int) then the data itself. The
> client reads 4 bytes, decodes it into the integer that tells it the length,
> and then reads the correct amount of bytes from the socket.

Exactly, sending the length first is the only way to know ahead of
time. Alternatively, if you know what the end of the data looks like,
you can look for that 'flag' as well, and stop trying to recv() after
that.

Some things that may be useful, though, are socket.settimeout() and
socket.setblocking(). More information is availible in the docs:
http://docs.python.org/library/socket.html.

You need to be careful with this, though, since network latency may
cause problems. Using these methods will keep your program from
sitting in recv() forever, though.

\t
--
http://tycho.ws


From twgray2007 at gmail.com  Sat Jul 18 18:04:41 2009
From: twgray2007 at gmail.com (twgray)
Date: Sat, 18 Jul 2009 15:04:41 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
Message-ID: <243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>

On Jul 18, 4:43?pm, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
> twgray wrote:
> > I am attempting to send a jpeg image file created on an embedded
> > device over a wifi socket to a Python client running on a Linux pc
> > (Ubuntu). ?All works well, except I don't know, on the pc client side,
> > what the file size is? ?
>
> You don't. Sockets are just endless streams of bytes. You will have to design some form
> of 'wire protocol' that includes the length of the message that is to be read.
> For instance a minimalistic protocol could be the following:
> Send 4 bytes that contain the length (an int) then the data itself. The client reads 4
> bytes, decodes it into the integer that tells it the length, and then reads the correct
> amount of bytes from the socket.
>
> --irmen

Thanks for the reply.  But, now I have a newbie Python question.  If I
send a 4 byte address from the embedded device, how do I convert that,
in Python, to a 4 byte, or long, number?


From tjreedy at udel.edu  Sat Jul 18 18:30:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 18 Jul 2009 18:30:08 -0400
Subject: invoke method on many instances
In-Reply-To: <CVl8m.141$MA3.16@nwrddc02.gnilink.net>
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>	<02701d35$0$5185$c3e8da3@news.astraweb.com>
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
Message-ID: <h3tidf$23k$1@ger.gmane.org>

Alan G Isaac wrote:
>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>> def apply2(itr, methodname, *args, **kwargs):
>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>     for item in itr:
>>>         f(item)
> 
> 
> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>> for obj in objects:
>>     getattr(obj, methodname)(*args, **kwargs)
> 
> 
> Are there any obvious considerations in choosing
> between those two?

I would use the straightforward getattr idiom.



From rickbking at comcast.net  Sat Jul 18 18:30:52 2009
From: rickbking at comcast.net (Rick King)
Date: Sat, 18 Jul 2009 18:30:52 -0400
Subject: uniicode and executing a process with subprocess.call, or os.system
Message-ID: <4A624D1C.5010503@comcast.net>

Hello,
I want to copy files using subprocess.call or os.system where the file 
names are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. 
Windows stores all the file names in unicode so they are displayed ok in 
explorer, and I can read them into my program with listdir(u'.'), etc. 
and work with the names in the program.

os.rename()

can be used to rename such files successfully.

But I want to be able to copy files using:

cmdstr = u'copy' +u' /Y "'+pair[0]+u'" "'+pair[1]+u'"\n'
cmdstr = cmdstr.encode(sys.getfilesystemencoding())
try: retcode = sp.call(cmdstr, shell=True) #SP=SUBPROCESS

but the encoding can't handle all the characters and so the file isn't 
found to be copied. sp.call() returns 1. 'mbcs' encoding doesn't work 
either. 'utf-8' doesn't work.

I am very confused about unicode. Can someone point me in the right 
direction?

windows xp sp2
python 2.6.2 unicode

Thanks!
Rick King
Southfield MI






From python at mrabarnett.plus.com  Sat Jul 18 19:05:48 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 00:05:48 +0100
Subject: How to receive a data file of unknown length using a python 
	socket?
In-Reply-To: <243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
Message-ID: <4A62554C.3040100@mrabarnett.plus.com>

twgray wrote:
> On Jul 18, 4:43 pm, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
>> twgray wrote:
>>> I am attempting to send a jpeg image file created on an embedded
>>> device over a wifi socket to a Python client running on a Linux pc
>>> (Ubuntu).  All works well, except I don't know, on the pc client side,
>>> what the file size is?  
>> You don't. Sockets are just endless streams of bytes. You will have to design some form
>> of 'wire protocol' that includes the length of the message that is to be read.
>> For instance a minimalistic protocol could be the following:
>> Send 4 bytes that contain the length (an int) then the data itself. The client reads 4
>> bytes, decodes it into the integer that tells it the length, and then reads the correct
>> amount of bytes from the socket.
>>
> Thanks for the reply.  But, now I have a newbie Python question.  If I
> send a 4 byte address from the embedded device, how do I convert that,
> in Python, to a 4 byte, or long, number?

If you send the length as 4 bytes then you'll have to decide whether
it's big-endian or little-endian. An alternative is to send the length
as characters, terminated by, say, '\n' or chr(0).


From clp2 at rebertia.com  Sat Jul 18 19:06:51 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 18 Jul 2009 16:06:51 -0700
Subject: uniicode and executing a process with subprocess.call, or 
	os.system
In-Reply-To: <4A624D1C.5010503@comcast.net>
References: <4A624D1C.5010503@comcast.net>
Message-ID: <50697b2c0907181606n2af8577ew3ad178f0463fa2d8@mail.gmail.com>

On Sat, Jul 18, 2009 at 3:30 PM, Rick King<rickbking at comcast.net> wrote:
> Hello,
> I want to copy files using subprocess.call or os.system where the file names
> are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. Windows
> stores all the file names in unicode so they are displayed ok in explorer,
> and I can read them into my program with listdir(u'.'), etc. and work with
> the names in the program.

You should try one of the copying functions in the shutil module
instead, it'll be much simpler than using subprocess:
http://docs.python.org/library/shutil.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From python at mrabarnett.plus.com  Sat Jul 18 19:07:12 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 00:07:12 +0100
Subject: uniicode and executing a process with subprocess.call,
	or os.system
In-Reply-To: <4A624D1C.5010503@comcast.net>
References: <4A624D1C.5010503@comcast.net>
Message-ID: <4A6255A0.20804@mrabarnett.plus.com>

Rick King wrote:
> Hello,
> I want to copy files using subprocess.call or os.system where the file 
> names are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. 
> Windows stores all the file names in unicode so they are displayed ok in 
> explorer, and I can read them into my program with listdir(u'.'), etc. 
> and work with the names in the program.
> 
> os.rename()
> 
> can be used to rename such files successfully.
> 
> But I want to be able to copy files using:
> 
> cmdstr = u'copy' +u' /Y "'+pair[0]+u'" "'+pair[1]+u'"\n'
> cmdstr = cmdstr.encode(sys.getfilesystemencoding())
> try: retcode = sp.call(cmdstr, shell=True) #SP=SUBPROCESS
> 
> but the encoding can't handle all the characters and so the file isn't 
> found to be copied. sp.call() returns 1. 'mbcs' encoding doesn't work 
> either. 'utf-8' doesn't work.
> 
> I am very confused about unicode. Can someone point me in the right 
> direction?
> 
> windows xp sp2
> python 2.6.2 unicode
> 
Use the shutil module.


From aahz at pythoncraft.com  Sat Jul 18 19:18:22 2009
From: aahz at pythoncraft.com (Aahz)
Date: 18 Jul 2009 16:18:22 -0700
Subject: python command running old version
References: <mailman.3369.1247937914.8015.python-list@python.org>
Message-ID: <h3tl7u$kmf$1@panix3.panix.com>

In article <mailman.3369.1247937914.8015.python-list at python.org>,
Tim Edwards  <timphotoman at gmail.com> wrote:
>
>I upgraded python this morning and entering python from the command
>line runs the old version.
>
>Just looked and it appears the old version is in /usr/bin while the
>new one is in /usr/local/bin/
>
>Besides changing the path order, how do I ensure it runs the new
>version? I'm sure I'll bang my head on the desk in shame as soon as
>I'm reminded.

You probably want to create an alias for command-line usage; scripts
should use the full path to the interpreter you want.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From sjmachin at lexicon.net  Sat Jul 18 19:26:21 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sat, 18 Jul 2009 16:26:21 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
Message-ID: <de887523-c9b1-4a5e-b75b-e54bda1d2847@f18g2000prf.googlegroups.com>

On Jul 19, 8:04?am, twgray <twgray2... at gmail.com> wrote:

> send a 4 byte address from the embedded device, how do I convert that,
> in Python, to a 4 byte, or long, number?

struct.unpack() is your friend. Presuming the embedded device is
little-endian, you do:

the_int = struct.unpack('<I', four_bytes)[0]

See http://docs.python.org/library/struct.html


From nobody at nowhere.com  Sat Jul 18 19:52:30 2009
From: nobody at nowhere.com (Nobody)
Date: Sun, 19 Jul 2009 00:52:30 +0100
Subject: How to receive a data file of unknown length using a python
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
Message-ID: <pan.2009.07.18.23.52.30.562000@nowhere.com>

On Sat, 18 Jul 2009 14:33:48 -0700, twgray wrote:

> It appears to be locking up in  'data=self.s.recv(MAXPACKETLEN)' on
> the final packet, which will always be less than MAXPACKETLEN.
> 
> I guess my question is, how do I detect end of data on the client side?

recv() should return zero when the sender closes its end of the connection.

Is the sender actually closing its end? If you are unsure, use a packet
sniffer such as tcpdump to look for a packet with the FIN flag.

If you need to keep the connection open for further transfers, you need to
incorporate some mechanism for identifying the end of the data into the
protocol. As others have suggested, prefixing the data by its length is
one option. Another is to use an end-of-data marker, but then you need a
mechanism to "escape" the marker if it occurs in the data. A length prefix
is probably simpler to implement, but has the disadvantage that you can't
start sending the data until you know how long it is going to be.



From foo at coo.com  Sat Jul 18 19:59:45 2009
From: foo at coo.com (Dave)
Date: Sun, 19 Jul 2009 00:59:45 +0100
Subject: Newbie question - running a command and looking at output
Message-ID: <4a6261ff@212.67.96.135>

I'm trying to run a command (arch -k) and check if the value returned is 
'sun4v' or not.


kirkby at t2:[~] $ arch -k
sun4v

In fact, I want to do 3 three things

1) Check if the system is Solaris.
2) If it is Solaris, check if 'arch -k' prints 'sun4v'
3) If both 1 and 2 are true, copy a file.


Since arch -k is not supported on all systems, the test for Solaris must 
be made first.

I have a test for Solaris (aka SunOS), which copies a file if the 
systems is running Solaris:

import os, shutil

if os.uname()[0] == 'SunOS':
    shutil.copy2('foo.c','bar.c')

How can I change that, so the copy is only performed if 'arch -k' prints 
'sun4v'?



-- 
I respectfully request that this message is not archived by companies as
unscrupulous as 'Experts Exchange' . In case you are unaware,
'Experts Exchange'  take questions posted on the web and try to find
idiots stupid enough to pay for the answers, which were posted freely
by others. They are leeches.


From foo at coo.com  Sat Jul 18 20:08:05 2009
From: foo at coo.com (Dave)
Date: Sun, 19 Jul 2009 01:08:05 +0100
Subject: Newbie question - running a command and looking at output
In-Reply-To: <4a6261ff@212.67.96.135>
References: <4a6261ff@212.67.96.135>
Message-ID: <4a6263f3@212.67.96.135>

Dave wrote:
> I'm trying to run a command (arch -k) and check if the value returned is 
> 'sun4v' or not.
> 
> 
> kirkby at t2:[~] $ arch -k
> sun4v
> 
> In fact, I want to do 3 three things
> 
> 1) Check if the system is Solaris.
> 2) If it is Solaris, check if 'arch -k' prints 'sun4v'
> 3) If both 1 and 2 are true, copy a file.
> 
> 
> Since arch -k is not supported on all systems, the test for Solaris must 
> be made first.
> 
> I have a test for Solaris (aka SunOS), which copies a file if the 
> systems is running Solaris:
> 
> import os, shutil
> 
> if os.uname()[0] == 'SunOS':
>    shutil.copy2('foo.c','bar.c')
> 
> How can I change that, so the copy is only performed if 'arch -k' prints 
> 'sun4v'?
> 
> 
> 

Actually, when I look at oluname, it does print sunnv:


 >>> import os
 >>> os.uname()
('SunOS', 't2', '5.10', 'Generic_141414-02', 'sun4v')


I guess all I need to do is check for the value of os.uname()[4] too.


-- 
I respectfully request that this message is not archived by companies as
unscrupulous as 'Experts Exchange' . In case you are unaware,
'Experts Exchange'  take questions posted on the web and try to find
idiots stupid enough to pay for the answers, which were posted freely
by others. They are leeches.


From sjmachin at lexicon.net  Sat Jul 18 20:12:32 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sat, 18 Jul 2009 17:12:32 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
Message-ID: <3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>

On Jul 19, 7:43?am, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
> twgray wrote:
> > I am attempting to send a jpeg image file created on an embedded
> > device over a wifi socket to a Python client running on a Linux pc
> > (Ubuntu). ?All works well, except I don't know, on the pc client side,
> > what the file size is? ?
>
> You don't. Sockets are just endless streams of bytes. You will have to design some form
> of 'wire protocol' that includes the length of the message that is to be read.

Apologies in advance for my ignorance -- the last time I dipped my toe
in that kind of water, protocols like zmodem and Kermit were all the
rage -- but I would have thought there would have been an off-the-
shelf library for peer-to-peer file transfer over a socket
interface ... not so?


From python at mrabarnett.plus.com  Sat Jul 18 20:33:32 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 01:33:32 +0100
Subject: How to receive a data file of unknown length using a
	python	socket?
In-Reply-To: <pan.2009.07.18.23.52.30.562000@nowhere.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<pan.2009.07.18.23.52.30.562000@nowhere.com>
Message-ID: <4A6269DC.1010409@mrabarnett.plus.com>

Nobody wrote:
> On Sat, 18 Jul 2009 14:33:48 -0700, twgray wrote:
> 
>> It appears to be locking up in  'data=self.s.recv(MAXPACKETLEN)' on
>> the final packet, which will always be less than MAXPACKETLEN.
>>
>> I guess my question is, how do I detect end of data on the client side?
> 
> recv() should return zero when the sender closes its end of the connection.
> 
> Is the sender actually closing its end? If you are unsure, use a packet
> sniffer such as tcpdump to look for a packet with the FIN flag.
> 
> If you need to keep the connection open for further transfers, you need to
> incorporate some mechanism for identifying the end of the data into the
> protocol. As others have suggested, prefixing the data by its length is
> one option. Another is to use an end-of-data marker, but then you need a
> mechanism to "escape" the marker if it occurs in the data. A length prefix
> is probably simpler to implement, but has the disadvantage that you can't
> start sending the data until you know how long it is going to be.
> 
You could send it in chunks, ending with a chunk length of zero.


From twgray2007 at gmail.com  Sat Jul 18 22:02:05 2009
From: twgray2007 at gmail.com (twgray)
Date: Sat, 18 Jul 2009 19:02:05 -0700 (PDT)
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<pan.2009.07.18.23.52.30.562000@nowhere.com>
	<mailman.3385.1247963593.8015.python-list@python.org>
Message-ID: <2b0e3c3c-2beb-46c3-acf6-86aee8caa2ed@b15g2000yqd.googlegroups.com>

On Jul 18, 7:33?pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Nobody wrote:
> > On Sat, 18 Jul 2009 14:33:48 -0700, twgray wrote:
>
> >> It appears to be locking up in ?'data=self.s.recv(MAXPACKETLEN)' on
> >> the final packet, which will always be less than MAXPACKETLEN.
>
> >> I guess my question is, how do I detect end of data on the client side?
>
> > recv() should return zero when the sender closes its end of the connection.
>
> > Is the sender actually closing its end? If you are unsure, use a packet
> > sniffer such as tcpdump to look for a packet with the FIN flag.
>
> > If you need to keep the connection open for further transfers, you need to
> > incorporate some mechanism for identifying the end of the data into the
> > protocol. As others have suggested, prefixing the data by its length is
> > one option. Another is to use an end-of-data marker, but then you need a
> > mechanism to "escape" the marker if it occurs in the data. A length prefix
> > is probably simpler to implement, but has the disadvantage that you can't
> > start sending the data until you know how long it is going to be.
>
> You could send it in chunks, ending with a chunk length of zero.

Thanks for the help!


From aahz at pythoncraft.com  Sat Jul 18 22:46:01 2009
From: aahz at pythoncraft.com (Aahz)
Date: 18 Jul 2009 19:46:01 -0700
Subject: How to receive a data file of unknown length using a python 
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<243077b4-2f96-4b60-afe3-cd0605a70f11@c14g2000yqm.googlegroups.com>
	<mailman.3382.1247958334.8015.python-list@python.org>
Message-ID: <h3u1d9$9m7$1@panix3.panix.com>

In article <mailman.3382.1247958334.8015.python-list at python.org>,
MRAB  <python at mrabarnett.plus.com> wrote:
>
>If you send the length as 4 bytes then you'll have to decide whether
>it's big-endian or little-endian. An alternative is to send the length
>as characters, terminated by, say, '\n' or chr(0).

Alternatively, make it a fixed-length string of bytes, zero-padded in
front.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From piet at cs.uu.nl  Sun Jul 19 02:55:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 08:55:20 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
Message-ID: <m2k525qi07.fsf@cs.uu.nl>

>>>>> John Machin <sjmachin at lexicon.net> (JM) wrote:

>JM> On Jul 19, 7:43?am, Irmen de Jong <irmen.NOS... at xs4all.nl> wrote:
>>> twgray wrote:
>>> > I am attempting to send a jpeg image file created on an embedded
>>> > device over a wifi socket to a Python client running on a Linux pc
>>> > (Ubuntu). ?All works well, except I don't know, on the pc client side,
>>> > what the file size is? ?
>>> 
>>> You don't. Sockets are just endless streams of bytes. You will have to design some form
>>> of 'wire protocol' that includes the length of the message that is to be read.

>JM> Apologies in advance for my ignorance -- the last time I dipped my toe
>JM> in that kind of water, protocols like zmodem and Kermit were all the
>JM> rage -- but I would have thought there would have been an off-the-
>JM> shelf library for peer-to-peer file transfer over a socket
>JM> interface ... not so?

Yes, many of them, for example HTTP or FTP. But I suppose they are
overkill in this situation. There are also remote procedure call
protocols which can do much more, like XMLRPC.

By the way if the image file
is the only thing you send, the client should close the socket after
sending and then the receiver will detect end of file which will be
detected by your `if len(data) == 0:'
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jeremy.cowles at gmail.com  Sun Jul 19 03:12:47 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Sun, 19 Jul 2009 00:12:47 -0700
Subject: Import hashlib fails, embedded
Message-ID: <373cf0740907190012q74da1d22le6b1bd03930acd78@mail.gmail.com>

I'm working on an embeddded Python interpreter (using the c-api) where we
are loading a custom, zipped copy of the standard Python library
(./lib/python25.zip).

Everything is working fine, but when I try to "import hashlib", i get the
following error:

Traceback (most recent call last):
  File "tryrun.py", line 2, in <module>
    import hashlib
  File "~/workspace/pyboinc/lib/python25.zip/hashlib.py", line 133, in
<module>
  File "~/workspace/pyboinc/lib/python25.zip/hashlib.py", line 60, in
__get_builtin_constructor
ImportError: No module named _md5

I assume this is related to a builtin or dynamically loaded C module, but
I'm not sure exactly what the problem is. Can anyone explain to me what is
going wrong? Other modules (like sys, os) are working fine, which may be
because they are pure-Python modules.

Here is the main function:

int main(int argc, const char* argv[])
{
    if (argc < 2) {
        cerr << "Module name missing\n";
        cerr << "usage: " << argv[0] << " module" << endl;
        return 1;
    }

    // get the python library name
    char* libname = get_lib_name();

    // try to copy the library from ./libname to ./lib/libname
    if (!copy_lib(libname)) {
        return 1;
    }

    Py_SetProgramName((char*)argv[0]);
    Py_SetPythonHome("./");
    Py_Initialize();

    if (argc > 0){
        PySys_SetArgv(argc-1, (char**)(argv+1));
    }

    {
        PyObject* syspath = PySys_GetObject("path");
        if (!syspath) {
            cerr << "Couldn't get sys.path" << endl;
            return 1;
        }
        if (!PyList_Check(syspath)) {
            cerr << "sys.path not a list" << endl;
            return 1;
        }
        PyObject* str = PyString_FromString(".");
        PyList_Append(syspath, str);
        Py_DECREF(str);
    }

    Py_InitModule("boinc", BoincMethods);

    PyObject* name = PyString_FromString(argv[1]);

    PyObject* mod = PyImport_Import(name);
    Py_DECREF(name);

    if (!mod) {
        cerr << "Error loading module" << endl;
        PyErr_Print();
        return 1;
    }
    Py_DECREF(mod);

    Py_Finalize();
}

--
Jeremy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/4cf2eb70/attachment-0001.html>

From __peter__ at web.de  Sun Jul 19 03:21:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Sun, 19 Jul 2009 09:21:15 +0200
Subject: how two join and arrange two files together
References: <6098.210.212.36.65.1247900961.squirrel@www.iisermohali.ac.in>
	<50697b2c0907180019l1efd087dv40f6a29b797e42b5@mail.gmail.com>
	<mailman.3351.1247902754.8015.python-list@python.org>
	<h3s3uu$8pk$00$1@news.t-online.com>
	<mailman.3352.1247909380.8015.python-list@python.org>
Message-ID: <h3uhgp$lr9$01$1@news.t-online.com>

amrita at iisermohali.ac.in wrote:

[please keep the correspondence on the mailing list/newsgroup]

> It is working sir, but my datas are on file when i replaced StringIO("")
> with open("filename.txt") then it is not printing the result properly,
> like in one file i have data like:---
> 33 ALA H = 7.57 N = 121.52 CA = 55.58 HA = 3.89 C = 179.24
> 38 ALA H = 8.29 N = 120.62 CA = 54.33 HA = 4.04 C = 178.95
> 8 ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98  C = 179.39
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18
> 21 ALA H = 7.66 N = 123.58 CA = 54.33 HA = 4.05 C = 179.35
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93
> in other:---
> 8 ALA  helix (helix_alpha, helix1)
> 21 ALA  helix (helix_alpha, helix2)
> 23 ALA  helix (helix_alpha, helix2)
> 33 ALA  helix (helix_alpha, helix3)
> 38 ALA  helix (helix_alpha, helix3)
> 49 ALA  bend
> and it is giving the result:-
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C = 177.18|
> 23 ALA H = 8.78 N = 120.16 CA = 55.84 HA = 4.14 C = 179.93|23 ALA  helix
> (helix_alpha, helix2)
> 38 ALA H = 8.29 N = 120.62 CA = 54.33 HA = 4.04 C = 178.95|38 ALA  helix
> (helix_alpha, helix3)
>           |49 ALA  bend
> 8 ALA H = 7.85 N = 123.95 CA = 54.67 HA = 2.98  C = 179.39|8 ALA  helix
> (helix_alpha, helix1)
> it is not printing the result for 33 and 21.

Hint: you have to adapt the key() function from

    def key(line):
        return line[:1]

to something that returns the same key for lines in the two files that 
belong together, and different keys for lines that don't.

Peter



From vs at it.uu.se  Sun Jul 19 04:04:10 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Sun, 19 Jul 2009 10:04:10 +0200
Subject: On out-of-date Python Applications
Message-ID: <4A62D37A.5080105@it.uu.se>

I am not a heavy user of Python; but, I do work with it and some of its 
application packages (e.g. PyODE), in an academic setting.
Many of these applications packages have a Windows installer which 
usually works fine. However, I also try to keep up with the latest 
release of Python, and this is where I often have problems. That is, the 
latest Windows installer provided for some of these applications will 
not install on the latest version of Python.

I do understand that there can be a time lag between the release of 
Python applications and the latest Python. I also appreciate the work of 
the people that are responsible for these applications.

My question is --- Is there anything I, as a user of an application 
package that is out-of-date with respect to the latest Python, can do to 
help in this process of bringing an application  up-to-date?

--V. Stokes



From motoom at xs4all.nl  Sun Jul 19 04:38:46 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Sun, 19 Jul 2009 10:38:46 +0200
Subject: On out-of-date Python Applications
In-Reply-To: <4A62D37A.5080105@it.uu.se>
References: <4A62D37A.5080105@it.uu.se>
Message-ID: <4A62DB96.8000302@xs4all.nl>

Virgil Stokes wrote:

 > some of these applications will
> not install on the latest version of Python.

Which version of Python precisely?



-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From mail at microcorp.co.za  Sun Jul 19 05:47:07 2009
From: mail at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 19 Jul 2009 11:47:07 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
Message-ID: <200907191147.07949.mail@microcorp.co.za>

On Sunday 19 July 2009 02:12:32 John Machin wrote:
>
> Apologies in advance for my ignorance -- the last time I dipped my toe
> in that kind of water, protocols like zmodem and Kermit were all the
> rage -- but I would have thought there would have been an off-the-
> shelf library for peer-to-peer file transfer over a socket
> interface ... not so?

*Grins at the references to Kermit and zmodem, 
and remembers Laplink and PC Anywhere*

If there is such a transfer beast in Python, I have 
not found it.
(There is an FTP module but that is not quite
the same thing)

I think it is because the network stuff is
all done in the OS or NFS and SAMBA 
now - with drag and drop support and 
other nice goodies.

I have ended up writing a netstring thingy,
that addresses the string transfer problem
by having a start sentinel, a four byte ASCII
length (so you can see it with a packet 
sniffer/displayer) and the rest of the
data escaped to take out the start
sentinel and the escape character.

It works, but the four byte ASCII limits the size
of what can be sent and received.

It guarantees to deliver either the whole
string, or fail, or timeout.

If anybody is interested I will attach the 
code here. It is not a big module.

This question seems to come up periodically
in different guises.

To the OP:

There are really very few valid ways of
solving the string transfer problem,
given a featureless stream of bytes
like a socket.

The first thing that must be addressed
is to sync up - you have to somehow
find the start of the thing as it comes 
past.

And the second is to find the end of the 
slug of data that you are transferring.

So the simplest way is to designate a byte 
as a start and end sentinel, and to make 
sure that such a byte does not occur in 
the data stream, other than as a start
and end marker.  This process is called
escaping, and the reverse is called
unescaping. (SDLC/HDLC does this at a bit 
pattern level)

Another way is to use time, namely to
rely on there being some minimum
time between slugs of data.  This 
does not work well on TCP/IP sockets,
as retries at the lower protocol levels
can give you false breaks in the stream.
It works well on direct connections like
RS-232 or RS-485/422 lines.

Classic netstrings send length, then data.
They rely on the lower level protocols and
the length sent for demarcation of
the slug, and work well if you connect,
send a slug or two, and disconnect.  They 
are not so hot for long running processes, 
where processors can drop out while
sending - there is no reliable way for a 
stable receiver to sync up again if it is
waiting for a slug that will not finish.

Adapting the netstring by adding a sync
character and time out is a compromise 
that I have found works well in practice.

- Hendrik



From sjmachin at lexicon.net  Sun Jul 19 06:17:49 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 19 Jul 2009 03:17:49 -0700 (PDT)
Subject: On out-of-date Python Applications
References: <mailman.3387.1247990649.8015.python-list@python.org>
Message-ID: <63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>

On Jul 19, 6:04?pm, Virgil Stokes <v... at it.uu.se> wrote:
> I am not a heavy user of Python; but, I do work with it and some of its
> application packages (e.g. PyODE), in an academic setting.
> Many of these applications packages have a Windows installer which
> usually works fine. However, I also try to keep up with the latest
> release of Python, and this is where I often have problems. That is, the
> latest Windows installer provided for some of these applications will
> not install on the latest version of Python.

If the package was written for 2.x and "the latest version of Python"
means 3.X, this is not surprising; your options are (1) wait until the
package maintainer releases a 3.x-compatible version (2) port it to
3.x yourself (3) use 2.6

Otherwise: What does "will not install" mean? Are these pure Python
packages or do they include C extensions (binary (pyd) or source?)? At
what stage of the installation does the installation fail? With what
error message(s)? With what versions of Python?



>
> I do understand that there can be a time lag between the release of
> Python applications and the latest Python. I also appreciate the work of
> the people that are responsible for these applications.
>
> My question is --- Is there anything I, as a user of an application
> package that is out-of-date with respect to the latest Python, can do to
> help in this process of bringing an application ?up-to-date?
>
> --V. Stokes



From r.grimm at science-computing.de  Sun Jul 19 07:08:00 2009
From: r.grimm at science-computing.de (Rainer Grimm)
Date: Sun, 19 Jul 2009 04:08:00 -0700 (PDT)
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
Message-ID: <f1bd8096-2956-4c15-acb7-711ee923a06f@c14g2000yqm.googlegroups.com>

Hallo Alan,
> def apply2(itr, methodname, *args, **kwargs):
> ? ? f = operator.methodcaller(methodname, *args, **kwargs)
> ? ? for item in itr:
> ? ? ? ? f(item)
you can do it in a functional way.

>>> class A(object):
...   def hello(self): return "hello: " + str
( self.__class__.__name__ )
...
>>> class B(A):pass
...
>>> class C(A):pass
...
>>> a=A()
>>> b=B()
>>> c=C()
>>> a.hello()
'hello: A'
>>> b.hello()
'hello: B'
>>> c.hello()
'hello: C'
>>>
>>> map( (lambda obj : getattr(obj,"hello")()),(a,b,c))
['hello: A', 'hello: B', 'hello: C']
>>> [ getattr(obj,"hello")() for obj in (a,b,c)]
['hello: A', 'hello: B', 'hello: C']

Greetings from Rottenburg,
Rainer


From hubaghdadi at gmail.com  Sun Jul 19 07:22:57 2009
From: hubaghdadi at gmail.com (Hussein B)
Date: Sun, 19 Jul 2009 04:22:57 -0700 (PDT)
Subject: A little help with pexpect
Message-ID: <d5f4fbbf-82fb-453c-a4d6-f4708f0bd46e@m11g2000yqh.googlegroups.com>

Hey,
I'm trying to execute a command over a remore server using pexpect
+++++++++++++++++
url = 'ssh internalserver'
res = pexpect.spawn(url)
print '1'
res.expect('.*ssword:')
print '2'
res.sendline('mypasswd')
print '3'
res.sendline('ls -aslh')
+++++++++++++++++
What I want to do is to send a couple of commands and get the
response.
How to do this?
Thanks.


From python at bdurham.com  Sun Jul 19 09:18:21 2009
From: python at bdurham.com (python at bdurham.com)
Date: Sun, 19 Jul 2009 09:18:21 -0400
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <200907191147.07949.mail@microcorp.co.za>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<4a624251$0$191$e4fe514c@news.xs4all.nl>
	<3960a105-f6cd-47c8-857c-d305b6c69b5e@v37g2000prg.googlegroups.com>
	<200907191147.07949.mail@microcorp.co.za>
Message-ID: <1248009501.29158.1325749595@webmail.messagingengine.com>

Hi Hendrik,

> I have ended up writing a netstring thingy, that addresses the string transfer problem by having a start sentinel, a four byte ASCII length (so you can see it with a packet sniffer/displayer) and the rest of the data escaped to take out the start sentinel and the escape character. It works, but the four byte ASCII limits the size of what can be sent and received. It guarantees to deliver either the whole string, or fail, or timeout.

> If anybody is interested I will attach the code here. It is not a big module.

I am interested in seeing your code and would be grateful if you shared
it with this list.

Thank you,
Malcolm


From piet at cs.uu.nl  Sun Jul 19 09:24:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 15:24:26 +0200
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<f1bd8096-2956-4c15-acb7-711ee923a06f@c14g2000yqm.googlegroups.com>
Message-ID: <m21vocrek5.fsf@cs.uu.nl>

>>>>> Rainer Grimm <r.grimm at science-computing.de> (RG) a ?crit:

>RG> Hallo Alan,
>>> def apply2(itr, methodname, *args, **kwargs):
>>> ? ? f = operator.methodcaller(methodname, *args, **kwargs)
>>> ? ? for item in itr:
>>> ? ? ? ? f(item)
>RG> you can do it in a functional way.

>>>>> class A(object):
>RG> ...   def hello(self): return "hello: " + str
>RG> ( self.__class__.__name__ )
>RG> ...
>>>>> class B(A):pass
>RG> ...
>>>>> class C(A):pass
>RG> ...
>>>>> a=A()
>>>>> b=B()
>>>>> c=C()
>>>>> a.hello()
>RG> 'hello: A'
>>>>> b.hello()
>RG> 'hello: B'
>>>>> c.hello()
>RG> 'hello: C'
>>>>> 
>>>>> map( (lambda obj : getattr(obj,"hello")()),(a,b,c))
>RG> ['hello: A', 'hello: B', 'hello: C']
>>>>> [ getattr(obj,"hello")() for obj in (a,b,c)]
>RG> ['hello: A', 'hello: B', 'hello: C']

But that creates an unnecessary list.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From victorsubervi at gmail.com  Sun Jul 19 09:24:43 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 19 Jul 2009 15:24:43 +0200
Subject: Auto Send URL
In-Reply-To: <50697b2c0907181032x6f0029dfs304a345ca2835690@mail.gmail.com>
References: <4dc0cfea0907170602u2da58ab1l3ad38fc457efa49a@mail.gmail.com>
	<50697b2c0907181032x6f0029dfs304a345ca2835690@mail.gmail.com>
Message-ID: <4dc0cfea0907190624g691688cdlef20acd77b88746b@mail.gmail.com>

Ah. How easy! Thank you.

On Sat, Jul 18, 2009 at 7:32 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> On Fri, Jul 17, 2009 at 6:02 AM, Victor Subervi<victorsubervi at gmail.com>
> wrote:
> > Hi;
> > I am trying to script code that automatically sends a Web site visitor to
> an
> > URL. Specifically, when they enter a value in a search box, I have that
> form
> > sent to a script that writes an URL acceptable to Google, then I want to
> > send the visitor off without him having to click another button. How do I
> do
> > this?
>
> Send back a webpage with a Refresh meta tag:
>
> <html>
>    <head>
>    <meta http-equiv="Refresh" content="0; url=http://YOUR-URL-HERE/">
>    </head>
> </html>
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/f25e90e4/attachment-0001.html>

From alan.isaac at gmail.com  Sun Jul 19 09:48:16 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sun, 19 Jul 2009 13:48:16 GMT
Subject: are user defined classes hashable?
Message-ID: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>

Are user defined classes hashable?
(The classes; *not* the instances!)

I want to use some classes as dictionary keys.
Python is not objecting,
but I'm not sure how to think about
whether this could be dangerous.
I'm inclined to guess it will be hashed by id
and this is OK.

Thanks for any insights,
Alan Isaac


From Nicolas.Dandrimont at crans.org  Sun Jul 19 10:07:57 2009
From: Nicolas.Dandrimont at crans.org (Nicolas Dandrimont)
Date: Sun, 19 Jul 2009 10:07:57 -0400
Subject: are user defined classes hashable?
In-Reply-To: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
Message-ID: <20090719140757.GB11029@dirichlet.crans.org>

* Alan G Isaac <alan.isaac at gmail.com> [2009-07-19 13:48:16 +0000]:

> Are user defined classes hashable?
> (The classes; *not* the instances!)
> 
> I want to use some classes as dictionary keys.
> Python is not objecting,
> but I'm not sure how to think about
> whether this could be dangerous.
> I'm inclined to guess it will be hashed by id
> and this is OK.

You can check for yourself:

In [1]: class Foo(object):
   ...:     pass
   ...: 

In [2]: foo = Foo()

In [3]: hash
hash

In [3]: hash(foo)
Out[3]: 15294992

In [4]: id(foo)
Out[4]: 15294992

So yes, by default, user-defined classes are hashable, by id. You can
override this behaviour by defining the __hash__ special method on
your object.

HTH,
-- 
Nicolas Dandrimont
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/ca0c9da8/attachment-0001.sig>

From mark.dufour at gmail.com  Sun Jul 19 10:30:57 2009
From: mark.dufour at gmail.com (Mark Dufour)
Date: Sun, 19 Jul 2009 16:30:57 +0200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
Message-ID: <8180ef690907190730t50ccc2f4sb7f489e7c9bb9fb8@mail.gmail.com>

Hi all,

I have just released version 0.2 of Shed Skin, an experimental
(restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).
It comes with 7 new example programs (for a total of 40 example
programs, at over 12,000 lines) and several important improvements/bug
fixes. See http://code.google.com/p/shedskin/wiki/ReleaseNotes for the
full changelog.

The new example programs consist of Disco, an elegant go player (see
http://shed-skin.blogspot.com/2009/07/disco-elegant-python-go-player.html),
a larger Voronoi implementation at 800 lines, a TSP algorithm
simulating ant colonies, a nicer neural network algorithm and three
compressors (Lempel-Ziv, huffman block, and arithmetic).

Other than bug fixes for these programs, this release adds some
important optimizations. First and foremost, inlining was greatly
improved, resulting in potential speedups across the board. Second,
loops such as 'for a, b in enumerate/zip(sequence[, sequence])' should
now be dramatically faster (also inside list comprehensions), by
avoiding allocation of intermediate tuples. Finally, basic list
slicing should now be much faster.
 	

Please try it out!
Mark Dufour.
-- 
"One of my most productive days was throwing away 1000 lines of code"
- Ken Thompson


From alan.isaac at gmail.com  Sun Jul 19 10:46:12 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Sun, 19 Jul 2009 14:46:12 GMT
Subject: are user defined classes hashable?
In-Reply-To: <mailman.3392.1248012803.8015.python-list@python.org>
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<mailman.3392.1248012803.8015.python-list@python.org>
Message-ID: <UkG8m.277$MA3.146@nwrddc02.gnilink.net>

> * Alan G Isaac <alan.isaac at gmail.com> [2009-07-19 13:48:16  +0000]:
>> Are user defined classes hashable? 
>> (The classes; *not* the instances!)
>> I'm inclined to guess it will be hashed by id and this is 
>> OK. 


On 7/19/2009 10:07 AM Nicolas Dandrimont apparently wrote:
> You can check for yourself:

> In [1]: class Foo(object):
>    ...:     pass
>    ...:

> In [2]: foo = Foo()

> In [3]: hash(foo)
> Out[3]: 15294992 

> In [4]: id(foo)
> Out[4]: 15294992 



Again, my question is about the class not its instances,
but still, checking as you suggest gives the same answer.

Thanks,
Alan


From piet at cs.uu.nl  Sun Jul 19 10:49:09 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 16:49:09 +0200
Subject: A little help with pexpect
References: <d5f4fbbf-82fb-453c-a4d6-f4708f0bd46e@m11g2000yqh.googlegroups.com>
Message-ID: <m2ws64pw2i.fsf@cs.uu.nl>

>>>>> Hussein B <hubaghdadi at gmail.com> (HB) wrote:

>HB> Hey,
>HB> I'm trying to execute a command over a remore server using pexpect
>HB> +++++++++++++++++
>HB> url = 'ssh internalserver'
>HB> res = pexpect.spawn(url)
>HB> print '1'
>HB> res.expect('.*ssword:')
>HB> print '2'
>HB> res.sendline('mypasswd')
>HB> print '3'
>HB> res.sendline('ls -aslh')
>HB> +++++++++++++++++
>HB> What I want to do is to send a couple of commands and get the
>HB> response.
>HB> How to do this?
>HB> Thanks.

You can read the output with res.readline() in a loop or similar. The
problem is when to stop. You could look in the returned string for the
prompt and hope the prompt doesn't accidentally occur in the output.

You can also do res.expect(prompt) and get res.before() Same problem
with accidentally occurrence of the prompt.

Another way is to use a timeout, e.g. with read_nonblocking or
specifying a timeout at the spawn call.

You can also consider using paramiko instead of pexpect. It gives you
considerably more control. For each command you van open a `channel' and
that acts more or less similar to a socket, i.e. you get a decent EOF at
the end of the command's output. This implies that you have to create a
new channel for each command, but it stays within the same SSH
connection (SSH allows subconnections).

Example:

>>> import paramiko
...Mumbles about deprecated modules...
>>> hostname='server.example.net'
>>> port = 22
>>> t = paramiko.Transport((hostname, port))
>>> username = 'user'
>>> password = '********'
>>> t.connect(username=username, password=password)

Open a channel for a command

>>> chan = t.open_session()
>>> chan.exec_command('ls -l')
>>> chan.recv(999999)
'total 0\ndrwxr-xr-x  2 user group 60 Apr  2  2009 Mail\ndrwx------  2 user group  6 Dec 27  2008 tmp\n'
>>> chan.recv(999999)
''

That was end of file.
Open a new channel for a new command

>>> chan = t.open_session()
>>> chan.exec_command('cat')
>>> chan.send('abcdefghijklmn\n')
15
>>> chan.recv(99)
'abcdefghijklmn\n'
>>> 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From resurtm at gmail.com  Sun Jul 19 11:03:21 2009
From: resurtm at gmail.com (resurtm)
Date: Sun, 19 Jul 2009 08:03:21 -0700 (PDT)
Subject: python, ctypes, callbacks -- access violation when calling callback
Message-ID: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>

Hello.

I'm trying to pass to the C function pointer to callback function from
python. But when i'm trying to do this i get access violation within
the DLL file when calling python callback.

Here is the python side code:

from ctypes import *

# ...

class NewtonBody(Structure):
  def __init__(self, pointer = 0):
     self.pointer = pointer

# ...

class Newton:
  def __init__(self):
     self._cdll = CDLL('newton.dll')
     self.world = NewtonWorld()

# ...

  # NewtonBodySetForceAndTorqueCallback
  def bodySetForceAndTorqueCallback(self, body):
     CALLBACK = CFUNCTYPE(c_int, POINTER(NewtonBody), c_float, c_int)
     def callback(a, b, c):
        print '1'
        return 0
     self._cdll.NewtonBodySetForceAndTorqueCallback(body.pointer,
CALLBACK(callback))
     return None

Traceback:

Traceback (most recent call last):
 File "Newton.py", line 119, in <module>
   newton.update(10.5)
 File "Newton.py", line 42, in update
   self._cdll.NewtonUpdate(self.world.pointer, c_float(timestep))
WindowsError: exception: access violation reading 0x3C888899

And finally prototype of function which i'm trying to call and
callback function type declarations:

typedef void (*NewtonApplyForceAndTorque) (const NewtonBody* body,
dFloat timestep, int threadIndex);

// ...

NEWTON_API void  NewtonBodySetForceAndTorqueCallback (const
NewtonBody* body, NewtonApplyForceAndTorque callback);

Can anybody explain my errors when trying to pass callback to DLL
function?

Thanks for advices and solutions!


From lists at cheimes.de  Sun Jul 19 11:09:37 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sun, 19 Jul 2009 17:09:37 +0200
Subject: python, ctypes,
	callbacks -- access violation when calling callback
In-Reply-To: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>
References: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>
Message-ID: <h3vcvg$iku$1@ger.gmane.org>

resurtm wrote:
> Can anybody explain my errors when trying to pass callback to DLL
> function?
> 
> Thanks for advices and solutions!

You have to keep a reference to the callback alive yourself. ctypes
doesn't increase the refernece counter of the function when you define a
callback. As soon as the ref counter reaches 0, the function object is
collected and the pointer to the callback is invalid.

You could assign it to a module global or instance variable.

Christian



From resurtm at gmail.com  Sun Jul 19 11:15:33 2009
From: resurtm at gmail.com (resurtm)
Date: Sun, 19 Jul 2009 08:15:33 -0700 (PDT)
Subject: python, ctypes, callbacks -- access violation when calling 
	callback
References: <690ea5a4-1c35-42b4-a259-a3471415668a@m11g2000yqh.googlegroups.com>
	<mailman.3394.1248016190.8015.python-list@python.org>
Message-ID: <8df80a1c-ada2-47a8-86ba-a9ed804c57f6@q11g2000yqi.googlegroups.com>

On 19 ???, 21:09, Christian Heimes <li... at cheimes.de> wrote:
> resurtm wrote:
> > Can anybody explain my errors when trying to pass callback to DLL
> > function?
>
> > Thanks for advices and solutions!
>
> You have to keep a reference to the callback alive yourself. ctypes
> doesn't increase the refernece counter of the function when you define a
> callback. As soon as the ref counter reaches 0, the function object is
> collected and the pointer to the callback is invalid.
>
> You could assign it to a module global or instance variable.
>
> Christian

Thanks for help Christian! It's working fine now! ;-)


From forman.simon at gmail.com  Sun Jul 19 11:21:01 2009
From: forman.simon at gmail.com (Calroc)
Date: Sun, 19 Jul 2009 08:21:01 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
Message-ID: <6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>

On Jul 9, 1:20 pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
[...]
> You'll excuse my skepticism about all these claims about how anyone can
> program, how easy it is to teach the fundamentals of Turing Machines and
> functional programming to anybody at all. Prove it. Where are your peer-
> reviewed studies demonstrating such successes on randomly chosen people,
> not self-selected motivated, higher-than-average intelligence students?

I'm engaged presently in starting a school to teach programming from
the ground up, based roughly on the curriculum outlined in the article
I mentioned.  I can't randomly select students but I do intend to
gather data about who does how well from what starting conditions.

I'm excited about formal methods because one, I just heard about them,
and two, they provide me with a much more well-fleshed-out way to
bridge rigorously from "raw" Turing machine models to higher order
abstractions.

I'm confident that anyone who can play Sudoku can learn programming
and formal methods.

> In the real world, human beings are prone to serious cognitive biases and
> errors. Our brains are buggy. Take any list of reasoning fallacies, and
> you'll find the majority of people have difficulty avoid them. The first
> struggle is to get them to even accept that they *are* fallacies, but
> even once they have intellectually accepted it, getting them to live up
> to that knowledge in practice is much, much harder.
>
> In fact I'd go further and say that *every single person*, no matter how
> intelligent and well-educated, will fall for cognitive biases and
> fallacious reasoning on a regular basis.

I agree completely.  One of my chief goals is to "debug" human
reasoning to whatever extent possible.  This is precisely where I
expect training in computer programming to come in handy.  The machine
symbol manipulator is not going to be fooled by reasoning fallacies.
Fluency in rigorous symbol manipulation can only help us cope with the
vagaries of our too-often sub-rational wetware.

I think the real win starts when computers can be used as a
communication medium, not for blogs and tweets and SMS txt and IM and
VoIP, but for reasoned symbolically coded discussion.


On Jul 9, 2:10 pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Wed, 08 Jul 2009 22:05:57 -0700, Simon Forman wrote:
> >> persistent idea "out there" that programming is a very accessible
> >> skill, like cooking or gardening, anyone can do it, and even profit
> >> from it, monetarily or otherwise, etc., and to some extent I am
>
> > Programming is not like any other human activity.
>
> In practice? In principle? Programming in principle is not the same as it
> is performed in practice.
>
> But in either case, programming requires both the logical reasoning of
> mathematics and the creativity of the arts. Funnily enough,
> mathematicians will tell you that mathematics requires the same, and so
> will the best artists. I think mathematicians, engineers, artists, even
> great chefs, will pour scorn on your claim that programming is not like
> any other human activity.

Well it's actually Dijkstra's claim, and I find it reasonable, that
programming has two novel or unique aspects not present in other areas
of human endeavor: vast scale and digital mechanism.

http://www.cs.utexas.edu/users/EWD/transcriptions/EWD10xx/EWD1036.html


> [...]
>
> > He talks about how "when all is said and done, the only thing computers
> > can do for us is to manipulate symbols and produce results of such
> > manipulations" and he emphasises the "uninterpreted" nature of
> > mechanical symbol manipulation, i.e. that the machine is doing it
> > mindlessly.
>
> "Manipulate symbols" is so abstract as to be pointless. By that

That's the "koan form", longhand he means the Boolean domain {true,
false}, the logical operations and their algebraic relationships, and
the means of using same to deduce new formulae.


> reasoning, I can build a "computer" consisting of a box open at the top.
> I represent a symbol by an object (say, a helium-filled balloon, or a
> stone), instead of a pattern of bits. I manipulate the symbol by holding
> the object over the box and letting go. If it flies up into the sky, that
> represents the symbol "Love is War", if it falls into the box, it
> represents the symbol "Strength is Blue", and if it just floats there, it
> represents "Cheddar Cheese". This is a deterministic, analog computer
> which manipulates symbols. Great.
>
> And utterly, utterly useless. So what is my computer lacking that real
> computers have? When you have answered that question, you'll see why
> Dijkstra's claim is under-specified.

Well, you said it yourself: your computer is lacking utility.


[...]
>
> What is an uninterpreted formula? If you don't interpret it, how can you
> distinguish it from random noise?

Uninterpreted formula means that you manipulate the symbols without
thinking about what they mean.  You just use the rules on the formulae
as such.  To be useful, once you're "done" with them you can consider
their meaning.  You can distinguish it at any time, but Dijktra's
saying that we should pay attention to the [mathematical, logical]
reasoning process as it's own thing, without reference to the meaning
of the symbols, at least temporarily.


[...]
>
> > If you're never exposed to that constellation of concepts that underpins
> > "mechanical symbol manipulation" you are adrift in a sea ("c", ha ha) of
> > abstractions.
>
> > However, if you /are/ exposed to the "so few and simple" rules of
> > manipulation the gates (no pun intended) to the kingdom are thrown wide.
>
> What nonsense. The keys to the kingdom are the abstractions.
>
> Here's an exercise for you, if you dare. It's not that difficult to
> remove the abstraction from integer addition, to explain it in terms of
> bit manipulation. If you prefer, you can write a Turing Machine instead.
>
> Now try doing the same thing for Quicksort. Don't worry, we'll wait.
>
> Once you've done that, let's see you implement a practical, scalable, non-
> toy webserver as a Turing Machine.
>
> No, it's not the fundamental operations that open the doors to the
> kingdom. It's the abstractions. The history of computing is to gain more
> and more power by leveraging better and better abstractions.

I agree that "better and better abstractions" are the key(s), but I
strongly disagree that the fundamental operations are not, uh, key to
those keys.

There are two intertwined phenomenon:

1) formulae, written in symbols

2) deriving new formulae by applying [in]formal methods to existing
formulae

The rules, and the application of those rules, are two separate but
compatible phenomenon. (Compatible in that you can encode the latter
in terms of the former. This is the essential "trick" of mechanized
thought.)

Now (1) is constantly being elaborated, these elaborations are the
"higher" abstractions we're talking about.

But (2) stays the same(-ish) no matter how high you go, and (2) is the
process by which all the higher (1)'s come from, so if we get it right
(and by right I mean of course by using rigorous proofs, formal
methods et. al.) from the get go and keep it right, we're golden.

I do literally intend to teach e.g. "integer addition ... in terms of
bit manipulation" and a bit of parsing too. But I intend to rapidly
bring students to a Forth or Forth-like stage, and then immediately
create simple parsers that implement, for example, C for loops, and
other "higher" abstractions.

Highly abridged, this is the curriculum: Enough about bits to bring
them to bytes, enough bytes to bring them to RAM, enough RAM to
implement a crude CPU, enough CPU to implement a bit of Forth, enough
Forth to implement parsers, and enough parsing (and compilation and
interpreting, etc.) to let them grok languages in general.

Formal methods gives me a wide straight road from each stage to the
next.

[...]
> > Quoting Dijkstra again [1]: "Before we part, I would like to invite you
> > to consider the following way of doing justice to computing's radical
> > novelty in an introductory programming course.
>
> > "On the one hand, we teach what looks like the predicate calculus, but
> > we do it very differently from the philosophers. In order to train the
> > novice programmer in the manipulation of uninterpreted formulae, we
> > teach it more as boolean algebra, familiarizing the student with all
> > algebraic properties of the logical connectives. To further sever the
> > links to intuition, we rename the values {true, false} of the boolean
> > domain as {black, white}.
>
> This is supposed to be a good thing?
>
> Oh my. It must be nice in that ivory tower, never having to deal with
> anyone who hasn't already been winnowed by years of study and self-
> selection before taking on a comp sci course.
>
> I don't think Dijkstra would have taken that suggestion seriously if he
> had to teach school kids instead of college adults.

I'm not going to teach it exactly like he outlines there, but I really
am going to try the curriculum I outlined.  I'll post videos. :]



> ...
>
> > (Did you read that last paragraph and think, "Well how the heck else are
> > you supposed to program a computer if not in a computer language?"?  If
> > so, well, that is kind of my point.)
>
> No. What I thought was, how the hell are you supposed to manipulate
> symbols without a language to describe what sort of manipulations you can
> do?

Direct-manipulation graphical Abstract Syntax Trees.



[...]
> > tables and arrays. He didn't even know that they were different
> > "things".
>
> I shall manfully resist the urge to make sarcastic comments about
> ignorant PHP developers, and instead refer you to my earlier reply to you
> about cognitive biases. For extra points, can you identify all the
> fallacious reasoning in that paragraph of yours?

I'll pass.  I should have resisted the urge to whinge about him in the
first place.



>
> But those abstractions just get in the way, according to you. He should
> be programming in the bare metal, doing pure symbol manipulation without
> language.

No, the abstractions are useful, but their utility is tied to their
reliability, which in turn derives from the formal rigour of the
proofs of the abstractions' correctness.

My issues with modern art are, that too many of these abstractions are
not /proven/, and they are both frozen and fractured by the existing
milieu of "static" mutually incompatible programming languages.

I see a possibility for something better.


> If programming is symbol manipulation, then you should remember that the
> user interface is also symbol manipulation, and it is a MUCH harder
> problem than databases, sorting, searching, and all the other problems
> you learn about in academia. The user interface has to communicate over a
> rich but noisy channel using multiple under-specified protocols to a
> couple of pounds of meat which processes information using buggy
> heuristics evolved over millions of years to find the ripe fruit, avoid
> being eaten, and have sex. If you think getting XML was hard, that's
> *nothing* compared to user interfaces.
>
> The fact that even bad UIs work at all is a credit to the heuristics,
> bugs and all, in the meat.

Ok, yes, but have you read Jef Raskin's "the Humane Interface"?

> > As for "a minimum of bugs"... sigh. The "minimum of bugs" is zero, if
> > you derive your "uninterpreted formulae" /correctly/.

Sorry.  I can't believe that I was so melodramatic.

> And the secret of getting rich on the stock market is to buy low, sell
> high. Very true, and very pointless. How do you derive the formula
> correctly?
>
> Do you have an algorithm to do so? If so, how do you know that algorithm
> is correct?

Well we know logic works, we can trust that. The algorithm of proving
the formula is logic.

> > Deriving provably
> > correct "programs" should be what computer science and computer
> > education are all about
>
> That's impossible. Not just impractical, or hard, or subject to hardware
> failures, but impossible.
>
> I really shouldn't need to raise this to anyone with pretensions of being
> a Computer Scientist and not just a programmer, but... try proving an
> arbitrary program will *halt*.
>
> If you can't do that, then what makes you think you can prove all useful,
> necessary programs are correct?

It may well be that there are useful, necessary programs that are
impossible to prove correct. I'm not trying to claim there aren't
such.

I think that wherever that's not the case, wherever useful necessary
programs can be proven, they should be.

It may be that flawless software is an unreachable asymptote, like the
speed of light for matter, but I'm (recently!) convinced that it's a
goal worthy of exploration and effort.

Just because it's unattainable doesn't make it undesirable.  And who
knows? Maybe the horse will learn to sing.

> > Again with Dijkstra[3]: "The prime paradigma of the pragmatic designer
> > is known as "poor man's induction", i.e. he believes in his design as
> > long as "it works", i.e. until faced with evidence to the contrary. (He
> > will then "fix the design".)
>
> Yes, that is the only way it can be.
>
> > The scientific designer, however, believes
> > in his design because he understands why it will work under all
> > circumstances.
>
> Really? Under *all* circumstances?
>
> Memory failures? Stray cosmic radiation flipping bits? Noise in the power
> supply?
>
> What's that you say? "That's cheating, the software designer can't be
> expected to deal with the actual reality of computers!!! We work in an
> abstract realm where computers never run out of memory, swapping never
> occurs, and the floating point unit is always correct!"

First, yes, that could be considered cheating.  We don't expect
automotive engineers to design for resistance to meteor strikes.
Second, those issues plague all programs, formally derived or not.
Formal methods certainly can't hurt.  Third, in cases where you do
want reliability in the face of things like cosmic rays you're going
to want to use formal methods to achieve it.

And last but not least, it may be possible to "parameterize" the
abstractions we derive with information about their susceptibility to
stability of their underlying abstractions.

> Fail enough. I don't want to make it too hard for you.
>
> Okay, so let's compare the mere "pragmatic designer" with his provisional
> expectation that his code is correct, and Dijkstra's "scientific
> designer". He understands his code is correct. Wonderful!
>
> Er, *how exactly* does he reach that understanding?
>
> He reasons about the logic of the program. Great! I can do that. See,
> here's a proof that binary search is correct. How easy this is.
>
> Now try it for some non-trivial piece of code. Say, the Linux kernel.
> This may take a while...

Well, I'd start with Minix 3...  But really the method would be to
build up provably correct compounds out of proven sub-assemblies.
Even if it takes a long time is it time wasted?  A provably correct OS
is kind of a neat idea IMO.

>
> What guarantee do we have that the scientific designer's reasoning was
> correct? I mean, sure he is convinced he has reasoned correctly, but he
> would, wouldn't he? If he was unsure, he'd keep reasoning (or ask for
> help), until he was sure. But being sure doesn't make him correct. It
> just makes him sure.
>
> So how do you verify the verification?

Peer review and run it through a mechanical verifier.  There is a self-
reflexive loop there but it's not infinite.  If it was we couldn't
implement any computer.

> And speaking of binary search:
[Bentley's binary search bug]

This is a perfect example of leaky abstraction. The C "integer"
doesn't behave like a "real" integer but part of the algorithm's
implementation relied on the tacit overlap between C ints and integers
up to a certain value.  This is the sort of thing that could be
annotated onto the symbolic representation of the algorithm and used
to compile provably correct machine code (for various platforms.)

If the same proven algorithm had been implemented on top of a correct
integer abstraction (like python's long int) it wouldn't have had that
bug.

(And yes, there would still be limits, truly vast arrays could
conceivably result in memory exhaustion during execution of the sort.
I think the answer there lies in being able to represent or calculate
the limits of an algorithm explicitly, the better to use it correctly
in other code.)

> Perhaps the "scientific designer" should be a little less arrogant, and
> take note of the lesson of real science: all knowledge is provisional and
> subject to correction and falsification.

(I apologize for my arrogance on behalf of formal methods, I just
found out about them and I'm all giddy and irritating.)

> Which really makes the "scientific designer" just a slightly more clever
> and effective "pragmatic designer", doesn't it?

Um, er, well, scientists are ultimate pragmatists, and Dijkstra's
description of "pragmatic designer" above could well be applied to
"scientific designers".  The difference turns on /why/ each person has
confidence is his design: one can prove mathematically that his design
is correct while the other is ... sure.

Whether or not the delivered software is actually flawless, the
difference seems to me more than just "slightly more clever and
effective".

>
> > The transition from pragmatic to scientific design would
> > indeed be a drastic change within the computer industry."
>
> Given Dijkstra's definition of "scientific design", it certainly would.
> It would be as drastic a change as the discovery of Immovable Objects and
> Irresistible Forces would be to engineering, or the invention of a
> Universal Solvent for chemistry, or any other impossibility.
>
> > "Obviously no errors" is the goal to strive for, and I am comfortable
> > calling anyone an amateur who prefers "no obvious errors."
>
> It's not a matter of preferring no obvious errors, as understanding the
> limitations of reality. You simply can't do better than no obvious errors
> (although of course you can do worse) -- the only question is what you
> call "obvious".

It may be expensive, it may be difficult, and it may certainly be
impossible, but I feel the shift from ad hoc software creation to
rigorous scientific software production is obvious.  To me it's like
the shift from astrology to astronomy, or from alchemy to chemistry.


~Simon


From victorsubervi at gmail.com  Sun Jul 19 11:35:58 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 19 Jul 2009 17:35:58 +0200
Subject: Getting a Form To Work
Message-ID: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>

Hi;
I have the following in a *.py page for the Web:

from primeNumbers import primeNumbers

try:
  num = form.getfirst('num')
except:
  num = ''
  msg = "Oops"

print "Content-Type: text/html"
print
print """
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<head xmlns="http://www.w3.org/1999/xhtml">
</head>
"""
if num != '':
  try:
    num = round(float(num))
    roots = primeNumbers(num)
    print roots
  except:
    msg += "We're sorry! You entered something that is not a number. Please
try again.<br />\n"
    num = ''
if num == '':
  print msg
  print "Num:", num
  print """
<form action="http://13gems.com/test-Calculators_frame.py" method="post">
<input type="text" name="num" size="20" maxlength="20" value="Enter number
here..." onfocus="this.value=''" />
<input type="image" src="http://13gems.com/images/search.jpg" name="search"
id="search" />
</form>
"""
print '</body></html>\n'

Now, "Oops" never gets printed, nor does the variable num (although a blank
space appears to print). I am calling the very page to which the form sends
its values. Assuming the imported module works, why don?t I get anything
printed?
TIA,
Victor
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/7d952367/attachment-0001.html>

From Nicolas.Dandrimont at crans.org  Sun Jul 19 11:39:31 2009
From: Nicolas.Dandrimont at crans.org (Nicolas Dandrimont)
Date: Sun, 19 Jul 2009 11:39:31 -0400
Subject: are user defined classes hashable?
In-Reply-To: <UkG8m.277$MA3.146@nwrddc02.gnilink.net>
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<mailman.3392.1248012803.8015.python-list@python.org>
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net>
Message-ID: <20090719153931.GA14960@dirichlet.crans.org>

* Alan G Isaac <alan.isaac at gmail.com> [2009-07-19 14:46:12 +0000]:
 
> Again, my question is about the class not its instances,
> but still, checking as you suggest gives the same answer.

That's what I get for answering before my coffee!

Cheers,
-- 
Nicolas Dandrimont

"Linux poses a real challenge for those with a taste for late-night
hacking (and/or conversations with God)."
(By Matt Welsh)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/1ed5e04d/attachment-0001.sig>

From sajmikins at gmail.com  Sun Jul 19 11:45:20 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Sun, 19 Jul 2009 08:45:20 -0700 (PDT)
Subject: Python code for testing well parenthesized expression
References: <4a5c7c04$0$16808$426a34cc@news.free.fr>
	<mailman.3088.1247577307.8015.python-list@python.org> 
	<Xns9C48B8D5619D0duncanbooth@127.0.0.1>
Message-ID: <d65f4dac-2aad-46cf-a997-9a6cbdaf165d@w41g2000yqb.googlegroups.com>

On Jul 14, 1:10?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> John Machin <sjmac... at lexicon.net> wrote:
> > Try an iterative version of checking that () [] and {}
> > are balanced and nested appropriately.
>
> Here's how I might approach the more general case:
>
> def balanced(s, parens=("()",)):
> ? ? '''
> ? ? Example:
> ? ? >>> balanced('aAAA(b[bb(c]c))')
> ? ? True
> ? ? >>> balanced('aAAA(b[bb(c]c))', parens=("()", "[]"))
> ? ? False
> ? ? '''
> ? ? s = re.sub("[^%s]+" % re.escape("".join(parens)), "", s)
> ? ? for i in range(len(s)/2):
> ? ? ? ? for p in parens:
> ? ? ? ? ? ? s = s.replace(p, "")
> ? ? return not s
>
> For short strings this is obviously slower than your 'iterative' function,
> but the run time mostly depends on the number of pairs of parentheses
> rather than the total length of the string, so for example it starts
> winning on a string with 2 pairs of parentheses about 75 characters long.


def balanced(s, pairs=('()', '[]', '{}')):
    opening = {}
    closing = {}
    for open_, close in pairs:
        opening[open_] = closing[close] = object()

    stack = []

    for char in s:

        marker = opening.get(char)
        if marker:
            stack.append(marker)
            continue

        marker = closing.get(char)
        if marker:
            try:
                if stack.pop() is not marker:
                    return False
            except IndexError:
                return False

    # All markers should be popped.
    return not stack


Can parse sequences other than strings. :]


From sjmachin at lexicon.net  Sun Jul 19 11:47:17 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 01:47:17 +1000
Subject: On out-of-date Python Applications
In-Reply-To: <4A632C9D.2010303@it.uu.se>
References: <mailman.3387.1247990649.8015.python-list@python.org>
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>
	<4A632C9D.2010303@it.uu.se>
Message-ID: <4A634005.6080505@lexicon.net>

On 20/07/2009 12:24 AM, Virgil Stokes wrote:
> John Machin wrote:
>> On Jul 19, 6:04 pm, Virgil Stokes <v... at it.uu.se> wrote:
>>   
>>> I am not a heavy user of Python; but, I do work with it and some of its
>>> application packages (e.g. PyODE), in an academic setting.
>>> Many of these applications packages have a Windows installer which
>>> usually works fine. However, I also try to keep up with the latest
>>> release of Python, and this is where I often have problems. That is, the
>>> latest Windows installer provided for some of these applications will
>>> not install on the latest version of Python.
>>>     
>>
>> If the package was written for 2.x and "the latest version of Python"
>> means 3.X, this is not surprising; your options are (1) wait until the
>> package maintainer releases a 3.x-compatible version (2) port it to
>> 3.x yourself (3) use 2.6
>>   
> Actually John,
> My question was about the more general case --- how to help with 
> upgrading applications; but, I will try to address your email.
>> Otherwise: What does "will not install" mean? 
> This means that when the Windows installer is executed it informs you 
> that you do not have a match between the application and the Python that 
> it finds on your Windows PC. You can easily find this out for yourself 
> by trying to install PyODE on a Windows platform with a Python version 
> later than 2.5.x.
>> Are these pure Python
>> packages or do they include C extensions (binary (pyd) or source?)? 
> Obviously, this depends on the application. In the particular case that 
> I mentioned (PyODE) I believe that there is a mix of C binaries and 
> Python code.
>> At
>> what stage of the installation does the installation fail? 
> In the initial stages.
>> With what
>> error message(s)? 
> In one specific case, the message is (paraphrasing) "You do not have 
> Python 2.5 installed" --- the installation is then aborted.
>> With what versions of Python?
>>   
> I have only Python 2.6.2 on my home Windows Vista PC and PyODE does not 
> have a Windows Installer for Python 2.6.
>>
>>
>>   
>>> I do understand that there can be a time lag between the release of
>>> Python applications and the latest Python. I also appreciate the work of
>>> the people that are responsible for these applications.
>>>
>>> My question is --- Is there anything I, as a user of an application
>>> package that is out-of-date with respect to the latest Python, can do to
>>> help in this process of bringing an application  up-to-date?
>>>
>>> --V. Stokes
>>>     
>>
>>   
> Note, again John, my question was about how I might assist (help) with 
> the updating of applications;

Your answers have been very helpful in determining exactly what your 
problem is; thank you.

> but, thank you for your interest in this.
> Perhaps, only the owner/responsible programmer for the application can 
> create a Windows installer,

Given a source distribution, a suitable C++ compiler, and the suspension 
of Murphy's Law, anyone should be able to (a) install it on their own 
machine (b) make a Windows installer.


> or perhaps others could assist with this --- 

Perhaps indeed ...

> this is what my question was about. I would be glad to assist if 
> possible :-)

Suggestions:

(1) contact the pyODE maintainer and ask, or check out the project's 
forums on sourceforge

(2) if you have a C++ compiler on your Windows box: get the source 
distribution, unpack it, ensure that the ODE_BASE in the setup.py points 
to your (existing) ODE 0.7 installation, do
     \python26\python setup.py install
and stand well back.

I have just tried this and got a ton of warnings from the compile and 3 
errors from the link:

build\lib.win32-2.6\ode.pyd : fatal error LNK1120: 3 unresolved externals
error: command '"C:\Program Files\Microsoft Visual Studio 
9.0\VC\BIN\link.exe"' failed with exit status 1120

C++ is not my bag and it's way past bedtime here, so I'll just paste in 
  the link output in the hope that someone can spot the problem:

C:\Program Files\Microsoft Visual Studio 9.0\VC\BIN\link.exe /DLL 
/nologo /INCREMENTAL:NO /LIBPATH:C:\ode\ode-0.7\lib\releaselib 
/LIBPATH:C:\python26\libs /LIBPATH:C:\python26\PCbuild ode.lib 
user32.lib /EXPORT:initode build\temp.win32-2.6\Release\ode_trimesh.obj 
/OUT:build\lib.win32-2.6\ode.pyd 
/IMPLIB:build\temp.win32-2.6\Release\ode.lib 
/MANIFESTFILE:build\temp.win32-2.6\Release\ode.pyd.manifest 
/NODEFAULTLIB:LIBCMT

    Creating library build\temp.win32-2.6\Release\ode.lib and object 
build\temp.win32-2.6\Release\ode.exp

ode.lib(error.obj) : error LNK2019: unresolved external symbol __iob 
referenced in function "void __cdecl printMessage(int,char const *,char 
const *,char *)" (?printMessage@@YAXHPBD0PAD at Z)

ode.lib(convex.obj) : error LNK2001: unresolved external symbol __iob

ode.lib(convex.obj) : error LNK2019: unresolved external symbol "public: 
void __thiscall std::_String_base::_Xran(void)const " 
(?_Xran at _String_base@std@@QBEXXZ) referenced in function "public: class 
std::basic_string<char,struct std::char_traits<char>,class 
std::allocator<char> > & __thiscall std::basic_string<char,struct 
std::char_traits<char>,class std::allocator<char> >::erase(unsigned 
int,unsigned int)" 
(?erase@?$basic_string at DU?$char_traits at D@std@@V?$allocator at D@2@@std@@QAEAAV12 at II@Z)

ode.lib(convex.obj) : error LNK2019: unresolved external symbol "public: 
void __thiscall std::_String_base::_Xlen(void)const " 
(?_Xlen at _String_base@std@@QBEXXZ) referenced in function "protected: 
bool __thiscall std::basic_string<char,struct 
std::char_traits<char>,class std::allocator<char> >::_Grow(unsigned 
int,bool)" 
(?_Grow@?$basic_string at DU?$char_traits at D@std@@V?$allocator at D@2@@std@@IAE_NI_N at Z)

build\lib.win32-2.6\ode.pyd : fatal error LNK1120: 3 unresolved externals

Cheers, John


From python at mrabarnett.plus.com  Sun Jul 19 11:52:45 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 16:52:45 +0100
Subject: Getting a Form To Work
In-Reply-To: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>
References: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>
Message-ID: <4A63414D.20408@mrabarnett.plus.com>

Victor Subervi wrote:
> Hi;
> I have the following in a *.py page for the Web:
> 
> from primeNumbers import primeNumbers
> 
> try:
>   num = form.getfirst('num')
> except:
>   num = ''
>   msg = "Oops"
> 
> print "Content-Type: text/html"
> print
> print """
> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" 
> "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
> <head xmlns="http://www.w3.org/1999/xhtml">
> </head>
> """
> if num != '':
>   try:
>     num = round(float(num))
>     roots = primeNumbers(num)
>     print roots
>   except:
>     msg += "We're sorry! You entered something that is not a number. 
> Please try again.<br />\n"
>     num = ''
> if num == '':
>   print msg
>   print "Num:", num

You get here if num == '', so you're printing out an empty string!

BTW, try not to use bare excepts.

>   print """
> <form action="http://13gems.com/test-Calculators_frame.py" method="post">
> <input type="text" name="num" size="20" maxlength="20" value="Enter 
> number here..." onfocus="this.value=''" />
> <input type="image" src="http://13gems.com/images/search.jpg" 
> name="search" id="search" />
> </form>
> """
> print '</body></html>\n'
> 
> Now, "Oops" never gets printed, nor does the variable num (although a 
> blank space appears to print). I am calling the very page to which the 
> form sends its values. Assuming the imported module works, why don?t I 
> get anything printed?
> 



From hendrik at microcorp.co.za  Sun Jul 19 12:07:54 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 19 Jul 2009 18:07:54 +0200
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <1248009501.29158.1325749595@webmail.messagingengine.com>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<200907191147.07949.mail@microcorp.co.za>
	<1248009501.29158.1325749595@webmail.messagingengine.com>
Message-ID: <200907191807.55071.hendrik@microcorp.co.za>

On Sunday 19 July 2009 15:18:21 python at bdurham.com wrote:
> Hi Hendrik,

> > If anybody is interested I will attach the code here. It is not a big
> > module.
>
> I am interested in seeing your code and would be grateful if you shared
> it with this list.

All right here it is.

Hope it helps

- Hendrik
-------------- next part --------------
A non-text attachment was scrubbed...
Name: netstring.py
Type: application/x-python
Size: 3474 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/e45876ef/attachment-0001.bin>

From python at bdurham.com  Sun Jul 19 12:09:12 2009
From: python at bdurham.com (python at bdurham.com)
Date: Sun, 19 Jul 2009 12:09:12 -0400
Subject: How to receive a data file of unknown length using a python
	socket?
In-Reply-To: <200907191807.55071.hendrik@microcorp.co.za>
References: <831d97bc-2323-42c3-9aeb-d62e4010c882@m11g2000yqh.googlegroups.com>
	<200907191147.07949.mail@microcorp.co.za>
	<1248009501.29158.1325749595@webmail.messagingengine.com>
	<200907191807.55071.hendrik@microcorp.co.za>
Message-ID: <1248019752.28310.1325763043@webmail.messagingengine.com>

>> I am interested in seeing your code and would be grateful if you shared it with this list.

> All right here it is. Hope it helps.

Hendrik,

Thank you very much!! (I'm not the OP, but found this thread
interesting)

Best regards,
Malcolm


From piet at cs.uu.nl  Sun Jul 19 13:08:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 19 Jul 2009 19:08:58 +0200
Subject: A little help with pexpect
References: <d5f4fbbf-82fb-453c-a4d6-f4708f0bd46e@m11g2000yqh.googlegroups.com>
	<m2ws64pw2i.fsf@cs.uu.nl>
Message-ID: <m2tz18ob11.fsf@cs.uu.nl>

>>>>> Piet van Oostrum <piet at cs.uu.nl> (PvO) wrote:
[snip]
>PvO> You can also consider using paramiko instead of pexpect. 
[snip]
>>>>> chan = t.open_session()
>>>>> chan.exec_command('cat')
>>>>> chan.send('abcdefghijklmn\n')

In a real program it is better to use sendall here, as send may decide
to send only part of its argument (the result will tell how many bytes
have been sent).
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From fft1976 at gmail.com  Sun Jul 19 13:33:39 2009
From: fft1976 at gmail.com (fft1976)
Date: Sun, 19 Jul 2009 10:33:39 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
Message-ID: <361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>

On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:

> E.g. the number system: In many Lisp
> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> it returns "0.6666666666", which will result in lots of fun for porting
> applications written for Python <= 2.6.

How do you explain that something as inferior as Python beat Lisp in
the market place despite starting 40 years later.


From python at mrabarnett.plus.com  Sun Jul 19 14:06:35 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 19:06:35 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <4A6360AB.4060003@mrabarnett.plus.com>

fft1976 wrote:
> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
> 
>> E.g. the number system: In many Lisp
>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
>> it returns "0.6666666666", which will result in lots of fun for porting
>> applications written for Python <= 2.6.
> 
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

It's all part of a Dutch conspiracy to take over the world! :-)


From python at mrabarnett.plus.com  Sun Jul 19 14:13:13 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 19 Jul 2009 19:13:13 +0100
Subject: Getting a Form To Work
In-Reply-To: <4dc0cfea0907191034h2146a185o5691b0ab705f3c8d@mail.gmail.com>
References: <4dc0cfea0907190835i1db3fa1es26b962c6b91610a3@mail.gmail.com>	
	<4A63414D.20408@mrabarnett.plus.com>
	<4dc0cfea0907191034h2146a185o5691b0ab705f3c8d@mail.gmail.com>
Message-ID: <4A636239.2010208@mrabarnett.plus.com>

Victor Subervi wrote:
> When the form comes up the first time, there is the default value for 
> num. When I fill in a number in the form and press send, even though the 
> form sends to itself (same page name), I would think it would read the 
> number sent. Here again is the code:
> 
> from primeNumbers import primeNumbers
> 
> try:
>   lang = form.getfirst('lang', 'en')
>   browser = form.getfirst('browser', 'all')
>   site = form.getfirst('site', 'bridge')
>   num = form.getfirst('num','')
> except:
>   pass
> 
> ourFile = string.split(__file__, "/")
> p = ourFile[len(ourFile) - 1]
> p = p[: - 9]
> site = ourFile[4][:-10]
> if site != '':
>   site = site[:-1]
> 
> print "Content-Type: text/html"
> print
> print """
> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" 
> "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
> <head xmlns="http://www.w3.org/1999/xhtml">
> </head>
> """
> if num != '':
>   num = round(float(num))
>   roots = primeNumbers(num)
>   print roots
> if num == '':
>   print """
> <form action="http://13gems.com/test-Calculators_frame.py" method="post">
> <input type="text" name="num" size="20" maxlength="20" value="Enter 
> number here..." onfocus="this.value=''" />
> <input type="image" src="http://13gems.com/images/search.jpg" 
> name="search" id="search" />
> </form>
> """
> print '</body></html>\n'
> 
> And why not use bare excepts? What is better?
> 
[snip]
An exception could be raised for a number of reasons, including
misspelling a name. You should catch only those exceptions you expect so
that others you don't expect, caused by bugs, will still be shown;
you'll then know there's a bug and can fix it.


From egarrulo at gmail.com  Sun Jul 19 14:22:30 2009
From: egarrulo at gmail.com (Elena)
Date: Sun, 19 Jul 2009 11:22:30 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <1542e10e-6ff0-43db-ab31-b73c0942ecf6@d32g2000yqh.googlegroups.com>

On Jul 19, 7:33?pm, fft1976 <fft1... at gmail.com> wrote:
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

To be mainstream a language has to fit in most programmers' minds.



From victorsubervi at gmail.com  Sun Jul 19 14:28:10 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 19 Jul 2009 20:28:10 +0200
Subject: Trouble With a Form
Message-ID: <4dc0cfea0907191128j4ed4e8det11d244769222b57e@mail.gmail.com>

Hi:
When the form comes up the first time, there is the default value for num.
When I fill in a number in the form and press send, even though the form
sends to itself (same page name), I would think it would read the number
sent. Here again is the code:

from primeNumbers import primeNumbers

try:
 lang = form.getfirst('lang', 'en')
 browser = form.getfirst('browser', 'all')
 site = form.getfirst('site', 'bridge')
 num = form.getfirst('num','')
except:
 pass

ourFile = string.split(__file__, "/")
p = ourFile[len(ourFile) - 1]
p = p[: - 9]
site = ourFile[4][:-10]
if site != '':
 site = site[:-1]

print "Content-Type: text/html"
print
print """
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<head xmlns="http://www.w3.org/1999/xhtml">
</head>
"""
if num != '':
 num = round(float(num))
 roots = primeNumbers(num)
 print roots
if num == '':
 print """
<form action="http://13gems.com/test-Calculators_frame.py" method="post">
<input type="text" name="num" size="20" maxlength="20" value="Enter number
here..." onfocus="this.value=''" />
<input type="image" src="http://13gems.com/images/search.jpg" name="search"
id="search" />
</form>
"""
print '</body></html>\n'
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/3d2c1c8e/attachment-0001.html>

From fb at frank-buss.de  Sun Jul 19 14:31:36 2009
From: fb at frank-buss.de (Frank Buss)
Date: Sun, 19 Jul 2009 20:31:36 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>

fft1976 wrote:

> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

Python is not that bad. Unlike Lisp, there is much less undefined behavior,
there is one free unique implementation on the 3 major platforms Linux,
Windows and MacOS X, which is stable, support multithreading and has a
default GUI library binding, which is difficult to find for Lisp (e.g. I
don't know of a free modern and stable Lisp implemenation with
mulithreading support for Windows, with a licence with which you can use it
in closed source commercial programs, like you can do with Python). Many
problems in the Lispbuilder mailing list are related to problems due to
different operating systems and Lisp implementations.

But maybe the most important point: The syntax looks simple compared to
Common Lisp (much less parentheses) and if you program in Python, it feels
easier for programmer newbies. As Sussman says: "undergraduate?s initial
experiences maximally productive". And this holds even for more experienced
programmers. If you know already a bit of C, it is easy to use Python, but
without the ability to do silly errors like writing out of array bounds (of
course, you can do this in Lisp, too, if you remember to set the safe mode
and if you use the right implementation). GC helps, too, to make the
programming task easier than in C. Some more arguments, e.g. 5 times less
program size than Java or C and more productive programmers:

http://www.artima.com/intv/speedP.html

(of course, an interview with Van Rossum might be a bit biased :-)

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From http  Sun Jul 19 14:51:17 2009
From: http (Paul Rubin)
Date: 19 Jul 2009 11:51:17 -0700
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
Message-ID: <7xljmk8q1m.fsf@ruckus.brouhaha.com>

Calroc <forman.simon at gmail.com> writes:
> I'm engaged presently in starting a school to teach programming from
> the ground up, based roughly on the curriculum outlined in the article
> I mentioned. ...
> I'm excited about formal methods because one, I just heard about them,

Formal methods are a big and complicated subject.  Right after you
heard about them is probably not the best time to start teaching them.
Better get to understand them yourself first.


From roy at panix.com  Sun Jul 19 15:09:28 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 19 Jul 2009 15:09:28 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <roy-362564.15092819072009@news.panix.com>

In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
 Frank Buss <fb at frank-buss.de> wrote:
 
> there is one free unique implementation on the 3 major platforms Linux,
> Windows and MacOS X

Most people would still consider Solaris to be a "major platform".


From rickbking at comcast.net  Sun Jul 19 15:32:16 2009
From: rickbking at comcast.net (Rick King)
Date: Sun, 19 Jul 2009 15:32:16 -0400
Subject: uniicode and executing a process with subprocess.call,
	or 	os.system
In-Reply-To: <50697b2c0907181606n2af8577ew3ad178f0463fa2d8@mail.gmail.com>
References: <4A624D1C.5010503@comcast.net>
	<50697b2c0907181606n2af8577ew3ad178f0463fa2d8@mail.gmail.com>
Message-ID: <4A6374C0.3000701@comcast.net>

Thanks. I looked around for alternatives but didn't find this one.
Rick

Chris Rebert wrote:
> On Sat, Jul 18, 2009 at 3:30 PM, Rick King<rickbking at comcast.net> wrote:
>   
>> Hello,
>> I want to copy files using subprocess.call or os.system where the file names
>> are non-ascii, e.g. Serbian(latin), c's and s's with hacheks,etc. Windows
>> stores all the file names in unicode so they are displayed ok in explorer,
>> and I can read them into my program with listdir(u'.'), etc. and work with
>> the names in the program.
>>     
>
> You should try one of the copying functions in the shutil module
> instead, it'll be much simpler than using subprocess:
> http://docs.python.org/library/shutil.html
>
> Cheers,
> Chris
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/cb8e1bb8/attachment-0001.html>

From tjreedy at udel.edu  Sun Jul 19 16:01:26 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 19 Jul 2009 16:01:26 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <roy-362564.15092819072009@news.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
Message-ID: <h3vu2m$um2$1@ger.gmane.org>

Roy Smith wrote:
> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>  Frank Buss <fb at frank-buss.de> wrote:
>  
>> there is one free unique implementation on the 3 major platforms Linux,
>> Windows and MacOS X
> 
> Most people would still consider Solaris to be a "major platform".

?? I do not, but I have no idea what comes in 4th after the other three 
by whatever metric.



From stef.mientki at gmail.com  Sun Jul 19 16:15:01 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Sun, 19 Jul 2009 22:15:01 +0200
Subject: any suggestions to synchronize typed text and speech ?
Message-ID: <4A637EC5.4010701@gmail.com>

hello,

I'm using Scintilla as a wxPython widget with great pleasure.
I now have an application where I want to make notes during a conversation,
but also want to record the speech during that conversation.
I'm using Scintilla as a wxPython widget for editing and PyAudio for the 
speech recording,
until so far everything works fine.
 
Here the problem part:
I need to synchronize the typed text with the sound during playback.
So if I click somewhere in the sound recording,
the line of text, typed that moment should be highlighted.
And vise versa, if the cursor in the text is moved and some special key 
is pressed,
the sound starting 10 or 20seconds earlier should be playbacked.

I though of adding bookmarks (because these are fixed in the text), and 
keep a list of bookmarks and sound pointers.
This idea should work, but there are only 31 bookmarks.

Any other suggestions ?

thanks,
Stef Mientki


From emile at fenx.com  Sun Jul 19 17:16:38 2009
From: emile at fenx.com (Emile van Sebille)
Date: Sun, 19 Jul 2009 14:16:38 -0700
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h3vu2m$um2$1@ger.gmane.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>	<roy-362564.15092819072009@news.panix.com>
	<h3vu2m$um2$1@ger.gmane.org>
Message-ID: <h402aa$9vf$1@ger.gmane.org>

On 7/19/2009 1:01 PM Terry Reedy said...
> Roy Smith wrote:
>> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>>  Frank Buss <fb at frank-buss.de> wrote:
>>  
>>> there is one free unique implementation on the 3 major platforms Linux,
>>> Windows and MacOS X
>>
>> Most people would still consider Solaris to be a "major platform".
> 
> ?? I do not, but I have no idea what comes in 4th after the other three 
> by whatever metric.
> 

one metric calls fourth as the iPhone OS...

http://marketshare.hitslink.com/report.aspx?qprid=8&qptimeframe=Y&qpsp=2009&qpmr=100&qpdt=1&qpct=0&qpob=UV%20DESC

Emile



From pavlovevidence at gmail.com  Sun Jul 19 17:46:42 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sun, 19 Jul 2009 14:46:42 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>

On Jul 19, 10:33?am, fft1976 <fft1... at gmail.com> wrote:
> On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:
>
> > E.g. the number system: In many Lisp
> > implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> > "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> > it returns "0.6666666666", which will result in lots of fun for porting
> > applications written for Python <= 2.6.
>
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

There was no reason to crosspost this here--looking at the original
thread on comp.lang.lisp it seems they were doing a surprisingly good
job discussing the issue.

I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
with a flamewar in another thread (LISP vs PROLOG vs HASKELL).


Carl Banks


From casevh at gmail.com  Sun Jul 19 18:05:33 2009
From: casevh at gmail.com (casevh)
Date: Sun, 19 Jul 2009 15:05:33 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com> 
	<4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com> 
	<4ae1e16f-124b-49c8-8364-36c59419be9b@d32g2000yqh.googlegroups.com>
Message-ID: <ac459e66-81c1-4672-a5fa-ebed4987c298@l5g2000pra.googlegroups.com>

GMPY 1.10 beta is now available. This version fixes an issue where
very large objects would be cached for reuse instead of being freed.

Source code and Windows installers may be found at
http://code.google.com/p/gmpy/downloads/list

casevh


From vippstar at gmail.com  Sun Jul 19 18:54:17 2009
From: vippstar at gmail.com (vippstar)
Date: Sun, 19 Jul 2009 15:54:17 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <f17a63a6-0a61-4e36-be38-6f0402f1f5ac@j32g2000yqh.googlegroups.com>

On Jul 19, 9:31?pm, Frank Buss <f... at frank-buss.de> wrote:
> fft1976 wrote:
> > How do you explain that something as inferior as Python beat Lisp in
> > the market place despite starting 40 years later.
<snip>
> But maybe the most important point: The syntax looks simple compared to
> Common Lisp (much less parentheses)
hahaha.


From tundra at tundraware.com  Sun Jul 19 19:29:07 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Sun, 19 Jul 2009 18:29:07 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
Message-ID: <lqmcj6-qij.ln1@ozzie.tundraware.com>

Carl Banks wrote:
> On Jul 19, 10:33 am, fft1976 <fft1... at gmail.com> wrote:
>> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
>>
>>> E.g. the number system: In many Lisp
>>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
>>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
>>> it returns "0.6666666666", which will result in lots of fun for porting
>>> applications written for Python <= 2.6.
>> How do you explain that something as inferior as Python beat Lisp in
>> the market place despite starting 40 years later.
> 
> There was no reason to crosspost this here--looking at the original
> thread on comp.lang.lisp it seems they were doing a surprisingly good
> job discussing the issue.
> 
> I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
> with a flamewar in another thread (LISP vs PROLOG vs HASKELL).
> 
> 
> Carl Banks

This is an incredibly important discussion and is much weaker because
it does not also include Pascal, BASIC, Ada, Oberon and Forth. In fact,
picking a computer language is the most important discussion in
Computer Science and eclipses even P=NP? in significance. I sure hope
we can keep this thread going for a few months. For guidance, see:


   http://www.tundraware.com/Technology/How-To-Pick-A-Programming-Language/



-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From marcusw at cox.net  Sun Jul 19 19:32:02 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sun, 19 Jul 2009 19:32:02 -0400
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <mailman.3406.1248034495.8015.python-list@python.org>
References: <mailman.3406.1248034495.8015.python-list@python.org>
Message-ID: <h40adj$bv6$1@adenine.netfront.net>

On 7/19/2009 4:15 PM, Stef Mientki wrote:
> hello,
> 
> I'm using Scintilla as a wxPython widget with great pleasure.
> I now have an application where I want to make notes during a conversation,
> but also want to record the speech during that conversation.
> I'm using Scintilla as a wxPython widget for editing and PyAudio for the 
> speech recording,
> until so far everything works fine.
> 
> Here the problem part:
> I need to synchronize the typed text with the sound during playback.
> So if I click somewhere in the sound recording,
> the line of text, typed that moment should be highlighted.
> And vise versa, if the cursor in the text is moved and some special key 
> is pressed,
> the sound starting 10 or 20seconds earlier should be playbacked.
> 
> I though of adding bookmarks (because these are fixed in the text), and 
> keep a list of bookmarks and sound pointers.
> This idea should work, but there are only 31 bookmarks.
> 
> Any other suggestions ?
> 
> thanks,
> Stef Mientki
That sounds like a very specialized type of thing, which only the few 
people with experience with wxPython, PyAudio, and Scintilla could help 
you with...

But you might try having a dictionary with notes and associated times, 
or just give each note a four-digit ID number at the beginning of it 
when it's entered and use that in the dictionary (to keep keys shorter). 
Or you could just do a little hack and increase the number of bookmarks 
allowed (seeing as source is available) :p

Marcus


From http  Sun Jul 19 19:35:01 2009
From: http (Paul Rubin)
Date: 19 Jul 2009 16:35:01 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
	<h3vu2m$um2$1@ger.gmane.org>
	<mailman.3407.1248038041.8015.python-list@python.org>
Message-ID: <7xiqho1c2i.fsf@ruckus.brouhaha.com>

Emile van Sebille <emile at fenx.com> writes:
> >> Most people would still consider Solaris to be a "major platform".
> > ?? I do not, but I have no idea what comes in 4th after the other
> > three by whatever metric.
> one metric calls fourth as the iPhone OS...
> http://marketshare.hitslink.com/report.aspx?qprid=8...

That metric is clearly wrong.  The #1 platform OS platform in terms of
number of units shipped is Javacard, which is in the SIM cards of
billions of GSM phones.


From pavlovevidence at gmail.com  Sun Jul 19 20:45:01 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sun, 19 Jul 2009 17:45:01 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com> 
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
Message-ID: <1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>

On Jul 19, 4:29?pm, Tim Daneliuk <tun... at tundraware.com> wrote:
> Carl Banks wrote:
> > On Jul 19, 10:33 am, fft1976 <fft1... at gmail.com> wrote:
> >> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
>
> >>> E.g. the number system: In many Lisp
> >>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> >>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> >>> it returns "0.6666666666", which will result in lots of fun for porting
> >>> applications written for Python <= 2.6.
> >> How do you explain that something as inferior as Python beat Lisp in
> >> the market place despite starting 40 years later.
>
> > There was no reason to crosspost this here--looking at the original
> > thread on comp.lang.lisp it seems they were doing a surprisingly good
> > job discussing the issue.
>
> > I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
> > with a flamewar in another thread (LISP vs PROLOG vs HASKELL).
>
> > Carl Banks
>
> This is an incredibly important discussion

It might be an important question but a discussion on Usenet about it
is utterly useless.


> and is much weaker because
> it does not also include Pascal, BASIC, Ada, Oberon and Forth.

In the same way that a movie is weaker because the director edited out
the bad scenes.


> In fact,
> picking a computer language is the most important discussion in
> Computer Science and eclipses even P=NP? in significance. I sure hope
> we can keep this thread going for a few months.

Please feel free to extend this flame-war along for a few months on
comp.lang.lisp.  Not here.


Carl Banks


From marek at xivilization.net  Sun Jul 19 20:51:49 2009
From: marek at xivilization.net (Marek Kubica)
Date: Mon, 20 Jul 2009 02:51:49 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
Message-ID: <20090720025149.326f0cfc@halmanfloyd.lan.local>

On Sun, 19 Jul 2009 15:09:28 -0400
Roy Smith <roy at panix.com> wrote:

> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>  Frank Buss <fb at frank-buss.de> wrote:
>  
> > there is one free unique implementation on the 3 major platforms
> > Linux, Windows and MacOS X
> 
> Most people would still consider Solaris to be a "major platform".

Depends on who you ask. On the desktop it doesn't matter at all
(fortunately, since everytime I work on Solaris I'm entering a world of
pain which is just slowly getting better with OpenSolaris), on the
server it (and other propietary Unices) is losing ground compared to
the free Unices.

But ok, let's say 3 major platforms: Unix, Windows and Mac OS X. Mac OS
X is formally a Unix but everything with GUI is non-Unix'y so it can be
considered a separate platform.

regards,
Marek


From marek at xivilization.net  Sun Jul 19 20:54:13 2009
From: marek at xivilization.net (Marek Kubica)
Date: Mon, 20 Jul 2009 02:54:13 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1542e10e-6ff0-43db-ab31-b73c0942ecf6@d32g2000yqh.googlegroups.com>
Message-ID: <20090720025413.12eb7fbf@halmanfloyd.lan.local>

On Sun, 19 Jul 2009 11:22:30 -0700 (PDT)
Elena <egarrulo at gmail.com> wrote:

> On Jul 19, 7:33?pm, fft1976 <fft1... at gmail.com> wrote:
> > How do you explain that something as inferior as Python beat Lisp in
> > the market place despite starting 40 years later.
> 
> To be mainstream a language has to fit in most programmers' minds.

Sometimes I wonder whether Python is not too complex for "most
programmers", since "most programmers" use Java, which is heavily
mainstream. Interesting whether it is in spite of the ridiculous
limitations or because of these. Probably a mix of both.

regards,
Marek



From research at johnohagan.com  Sun Jul 19 21:44:44 2009
From: research at johnohagan.com (John O'Hagan)
Date: Mon, 20 Jul 2009 01:44:44 +0000
Subject: question on input function
In-Reply-To: <346922.15108.qm@web56908.mail.re3.yahoo.com>
References: <346922.15108.qm@web56908.mail.re3.yahoo.com>
Message-ID: <200907200144.44417.research@johnohagan.com>

On Mon, 20 Jul 2009, Richel Satumbaga wrote:
> I am just learning python then I encountered an certain point in terms of
> using the input function of python. the source code:
>                        eq = input("enter an equation:");
>                        print " the result is : ";
>
>
> the output seen in the command window:
>
> enter an equation:[m*x+b for m in (0,10,1),for x in (1,11,1), for b in
> (2,12,1)]
>
> Traceback (most recent call last):
>   File "C:/Python26/try", line 1, in <module>
>     eq = input("enter an equation:");
>   File "<string>", line 1
>     [m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]
>                                ^
> SyntaxError: invalid syntax

[...]

It's the extra commas in your list comprehension.This should work:

[m*x+b for m in (0,10,1) for x in (1,11,1) for b in (2,12,1)]

HTH,

John




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090720/273f60b8/attachment-0001.html>

From rlsatumbaga at yahoo.com  Sun Jul 19 22:07:07 2009
From: rlsatumbaga at yahoo.com (Richel Satumbaga)
Date: Sun, 19 Jul 2009 19:07:07 -0700 (PDT)
Subject: question on input function
Message-ID: <346922.15108.qm@web56908.mail.re3.yahoo.com>

I am just learning python then I encountered an certain point in terms of using the input function of python.
the source code:
?????????????????????? eq = input("enter an equation:");
?????????????????????? print " the result is : ";


the output seen in the command window:
>>>
enter an equation:[m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]

Traceback (most recent call last):
? File "C:/Python26/try", line 1, in <module>
??? eq = input("enter an equation:");
? File "<string>", line 1
??? [m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]
?????????????????????????????? ^
SyntaxError: invalid syntax

????????????????? Is there any other way to enter those? or it must be coded in the source code?
If in source code is it like in matlab where one can type:

x = [0:1:10]; 

to define the range of x which is form 0 to 10 with the increment of? 1.

Thanks 

Ann



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090719/1e922a04/attachment-0001.html>

From roy at panix.com  Sun Jul 19 22:07:34 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 19 Jul 2009 22:07:34 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<roy-362564.15092819072009@news.panix.com>
	<20090720025149.326f0cfc@halmanfloyd.lan.local>
Message-ID: <roy-CF08FF.22073419072009@news.panix.com>

In article <20090720025149.326f0cfc at halmanfloyd.lan.local>,
 Marek Kubica <marek at xivilization.net> wrote:

> > > there is one free unique implementation on the 3 major platforms
> > > Linux, Windows and MacOS X
> > 
> > Most people would still consider Solaris to be a "major platform".
> 
> Depends on who you ask. On the desktop it doesn't matter at all
> (fortunately, since everytime I work on Solaris I'm entering a world of
> pain which is just slowly getting better with OpenSolaris), on the
> server it (and other propietary Unices) is losing ground compared to
> the free Unices.

Clearly, there's not much (if any) Solaris on the desktop.  But it's sure 
alive and kicking in the server world.

One of the things I like about Python is not just how portable is it is, 
but how easy it is to build and deploy.  We build our product on Windows, N 
different Linux distros, Solaris, HPUX, AIX, and OSX.  I've built Python 
for all of those platforms.  Then, I checked the install areas into 
Perforce.  Deploying is as simple as checking out the right sandbox.

We've gone through the same exercise for Perl.  That was a lot more 
painful.


From fatkinson at mishmash.com  Sun Jul 19 22:22:37 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Sun, 19 Jul 2009 19:22:37 -0700
Subject: Final Project
Message-ID: <v6l765lvk1tf6l63gkfjli64boo394cl7a@4ax.com>

	I'm looking for some ideas here.  

	I think I've mentioned I am taking a course in Python and PHP.
The professor wants each of us to pick a project to write in both
languages.  It has to be something fairly complex and I'd like for it
to be something that would be useful on my Web site(s).  

	I would be grateful for any and all suggestions.  

	Regards, 





						Fred 


From clp2 at rebertia.com  Sun Jul 19 22:44:45 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 19 Jul 2009 19:44:45 -0700
Subject: question on input function
In-Reply-To: <346922.15108.qm@web56908.mail.re3.yahoo.com>
References: <346922.15108.qm@web56908.mail.re3.yahoo.com>
Message-ID: <50697b2c0907191944i43d14c85m270bd391e366ec21@mail.gmail.com>

On Sun, Jul 19, 2009 at 7:07 PM, Richel Satumbaga<rlsatumbaga at yahoo.com> wrote:
> I am just learning python then I encountered an certain point in terms of
> using the input function of python.
> the source code:
> ?????????????????????? eq = input("enter an equation:");
> ?????????????????????? print " the result is : ";
>
>
> the output seen in the command window:
>>>>
> enter an equation:[m*x+b for m in (0,10,1),for x in (1,11,1), for b in
> (2,12,1)]
>
> Traceback (most recent call last):
> ? File "C:/Python26/try", line 1, in <module>
> ??? eq = input("enter an equation:");
> ? File "<string>", line 1
> ??? [m*x+b for m in (0,10,1),for x in (1,11,1), for b in (2,12,1)]
> ?????????????????????????????? ^
> SyntaxError: invalid syntax
>
> ????????????????? Is there any other way to enter those? or it must be coded
> in the source code?
> If in source code is it like in matlab where one can type:
>
> x = [0:1:10];
>
> to define the range of x which is form 0 to 10 with the increment of? 1.

First, commas between the "for"s are not permitted, which gives us:

[m*x+b for m in (0,10,1) for x in (1,11,1) for b in (2,12,1)]

However, in Python, (i, j, k) is just a tuple (MATLAB: 1D matrix) of
the items i, j, and k.
What you want is a range, which is understandably created using the
range() function.
A step of 1 and a start of 0 are the defaults, and the stop value is
always excluded, so the code becomes:

[m*x+b for m in range(11) for x in range(1,12) for b in range(2,13)]

Which should be what you want.

For further explanation of the range() function:
range(b) - the numbers from 0 to b-1 with a step of 1
range(a,b) - the numbers from a to b-1 with a step of 1
range(a,b,c) - the numbers from a to b-1 with a step of c

Hope that helps.

Cheers,
Chris
-- 
http://blog.rebertia.com


From denize.paul at gmail.com  Sun Jul 19 22:57:50 2009
From: denize.paul at gmail.com (pdenize)
Date: Sun, 19 Jul 2009 19:57:50 -0700 (PDT)
Subject: Managing non-ascii filenames in python
Message-ID: <60a305de-0552-4f77-9051-d87149d308c7@y10g2000prg.googlegroups.com>

I created the following filename in windows just as a test -
?D?n?ld?s? N?ph?ws? deg?.txt
The quotes are non -ascii, many non english characters, long hyphen
etc.

Now in DOS I can do a directory and it translates them all to
something close.
"D?n?ld'sT N?ph?ws" deg?.txt

I thought the correct way to do this in python would be to scan the
dir
files=os.listdir(os.path.dirname( os.path.realpath( __file__ ) ))

then print the filenames
for filename in files:
  print filename

but as expected teh filename is not correct - so correct it using the
file sysytems encoding

  print filename.decode(sys.getfilesystemencoding())

But I get
UnicodeEncodeError: 'charmap' codec can't encode character u'\u2014'
in position 6: character maps to <undefined>

All was working well till these characters came along

I need to be able to write (a representation) to the screen (and I
don't see why I should not get something as good as DOS shows).

Write it to an XML file in UTF-8

and write it to a text file and be able to read it back in.
Again I was supprised that this was also difficult - it appears that
the file also wanted ascii.  Should I have to open the file in binary
for write (I expect so) but then what encoding should I write in?

I have been beating myself up with this for weeks as I get it working
then come across some outher character that causes it all to stop
again.

Please help.


From mensanator at aol.com  Mon Jul 20 00:12:35 2009
From: mensanator at aol.com (Mensanator)
Date: Sun, 19 Jul 2009 21:12:35 -0700 (PDT)
Subject: ANN: GMPY 1.10 alpha with support for Python 3
References: <mailman.2695.1246892380.8015.python-announce-list@python.org> 
	<c1dfc09c-a747-43b9-8594-5d987c38ec50@o9g2000prg.googlegroups.com> 
	<fc93940e-a6b5-4713-a859-cb05bfb12300@h18g2000yqj.googlegroups.com> 
	<4acb279c-2d90-4976-8e45-648624ecf542@18g2000yqa.googlegroups.com> 
	<4ae1e16f-124b-49c8-8364-36c59419be9b@d32g2000yqh.googlegroups.com> 
	<ac459e66-81c1-4672-a5fa-ebed4987c298@l5g2000pra.googlegroups.com>
Message-ID: <2c3e8fc0-e814-4020-bcfd-d3d02cc62dea@t13g2000yqt.googlegroups.com>

On Jul 19, 5:05?pm, casevh <cas... at gmail.com> wrote:
> GMPY 1.10 beta is now available. This version fixes an issue where
> very large objects would be cached for reuse instead of being freed.

Excellent! That explains the funny memory usage graph.

>
> Source code and Windows installers may be found athttp://code.google.com/p/gmpy/downloads/list
>

Test results:

import collatz_functions as cf
# imports gmpy
# the cf.Type12MH function does the equivalent
# of the pure Python version of the function
# using gmpy
import time

#3.1 gmpy 1.10 beta
#
t0 = time.time()
n=10
for k in range(1,n):
  for i in range(1,n-2):
    print((str(cf.gmpy.numdigits(cf.Type12MH(k,i))).zfill(n)),end=' ')
  print()
print()
t1 = time.time()

print(t1-t0)

# 3.1 pure Python
#
##t0 = time.time()
##n=10
##for k in range(1,n):
##  for i in range(1,n-2):
##    print((str(cf.gmpy.numdigits( \
##      2**(6*((i-1)*9**(k-1)+(9**(k-1)-1)//2+1)-1)-1  \
##      )).zfill(n)),end=' ')
##  print()
##print()
##t1 = time.time()
##
##print(t1-t0)


##  3.1 gmpy 1.10 alpha
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##3.32299995422
## funny memory usage display, different between 2.6 & 3.1, but funny
regardless,
## memory remains allocated (~700 MB) when program halts

##  3.1 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##338.832000017
## memory usage seems normal, runs slow enough to observe memory being
allocated
## and freed and remains freed when program halts

##  2.6 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##aborted after ONE FULL WEEK of processing (only 8 of 9 rows
completed)

##  Something funny happened here. By the time I ran this test, there
##  were 14 orphaned copies of pythonw.exe present, at least one of
which
##  was still running along with the real pair executing the program.
Yet
##  the Performance only registered ~50%. Normally, this would be 100%
if
##  two programs were running. Pure Python is a LOT slower than gmpy,
##  but not THAT slow. These orphaned processes may be a Python 3.1
issue.

##===================================================================

## 3.1 gmpy 1.10 beta
##
##  0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##  0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##  0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##  0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##  0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##  0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##  0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##  0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##  0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##  2.41799998283
## memory usage now appears normal, no more allocated memory when
program halts
## and it's so fast all we see on Performance graph is a small blip,
much better
## than the 700-1400 MB it was allocating before.

## 3.1 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##339.611999989
## looks like gmpy about a 100 times faster. I knew there was a reason
I
## won't use Python without gmpy.

## 2.6 gmpy 1.10 beta
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##2.68400001526

## 2.6 pure Python
##
##0000000002 0000000004 0000000006 0000000007 0000000009 0000000011
0000000013
##0000000009 0000000025 0000000042 0000000058 0000000074 0000000091
0000000107
##0000000074 0000000221 0000000367 0000000513 0000000659 0000000806
0000000952
##0000000659 0000001976 0000003293 0000004610 0000005926 0000007243
0000008560
##0000005926 0000017777 0000029627 0000041477 0000053328 0000065178
0000077028
##0000053328 0000159981 0000266634 0000373287 0000479940 0000586593
0000693246
##0000479940 0001439818 0002399696 0003359574 0004319453 0005279331
0006239209
##0004319453 0012958355 0021597258 0030236161 0038875064 0047513967
0056152869
##0038875064 0116625189 0194375315 0272125440 0349875565 0427625691
0505375816
##
##338.987999916
## ah, that's more like it. no more pythonw.exe thrashing. I was
almost ready
## to drop version 2.6 like a live grenade, but that was based on some
other
## fault apparently. it may be 3.1 I have to drop.

I still got a single instance of an orphaned pythonw.exe, but this
happened during a quick attempt at provoking it during a 3.1 pure
Python test, so I have no reason to suspect gmpy (previously, I
thought it may be related to the memory leak).

I've got an idea on how to reliably provoke this which I'll try to
work up later (and won't even load gmpy to make sure it's not
involved).

> casevh



From steven at REMOVE.THIS.cybersource.com.au  Mon Jul 20 01:11:17 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 20 Jul 2009 05:11:17 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>

On Sun, 19 Jul 2009 10:33:39 -0700, fft1976 wrote:

> On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:
> 
>> E.g. the number system: In many Lisp
>> implementations (/ 2 3) results in the fractional object 2/3. In Python
>> 2.6 "2 / 3" results in "0". Looks like with Python 3.1 they have fixed
>> it, now it returns "0.6666666666", which will result in lots of fun for
>> porting applications written for Python <= 2.6.
> 
> How do you explain that something as inferior as Python beat Lisp in the
> market place despite starting 40 years later.

http://www.jwz.org/doc/worse-is-better.html


Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing 
to do. It's the right thing to do if you're doing integer maths.


-- 
Steven


From fb at frank-buss.de  Mon Jul 20 01:18:01 2009
From: fb at frank-buss.de (Frank Buss)
Date: Mon, 20 Jul 2009 07:18:01 +0200
Subject: Final Project
References: <v6l765lvk1tf6l63gkfjli64boo394cl7a@4ax.com>
Message-ID: <1ctywmarsqqzd.y7fg69mkbshy$.dlg@40tude.net>

Fred Atkinson wrote:

> 	I'm looking for some ideas here.  
> 
> 	I think I've mentioned I am taking a course in Python and PHP.
> The professor wants each of us to pick a project to write in both
> languages.  It has to be something fairly complex and I'd like for it
> to be something that would be useful on my Web site(s).  
> 
> 	I would be grateful for any and all suggestions.  

Useful for your webpage depends very much on what you think what you need
and it is difficult to answer by others who don't know your needs.

E.g. useful for me was a Python Blender script to create wireframe and
solid models of platonic solids and a program for geodesic domes of
parametrized detail level:

http://www.frank-buss.de/shapeways/dome.py
http://www.shapeways.com/mydesign?user_id=19157

It is my first bigger Python program, so ideas how it could be improved are
welcome.

Would be an interesting project to create a renderer for it, which can
calculate this and other geometric figures as a CGI script to an image and
display the result in the browser. Try this in PHP and Python and write
about the experiences you made. Maybe don't forget to limit the access to
the webpage or the size of the output image, to avoid trouble with your
hosting provider, if you don't have your own server and anything slows down
because of your rendering task :-)

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From tundra at tundraware.com  Mon Jul 20 01:18:58 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Mon, 20 Jul 2009 00:18:58 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
	<1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
Message-ID: <jabdj6-qij.ln1@ozzie.tundraware.com>

Carl Banks wrote:
> On Jul 19, 4:29 pm, Tim Daneliuk <tun... at tundraware.com> wrote:
>> Carl Banks wrote:
>>> On Jul 19, 10:33 am, fft1976 <fft1... at gmail.com> wrote:
>>>> On Jul 19, 9:55 am, Frank Buss <f... at frank-buss.de> wrote:
>>>>> E.g. the number system: In many Lisp
>>>>> implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
>>>>> "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
>>>>> it returns "0.6666666666", which will result in lots of fun for porting
>>>>> applications written for Python <= 2.6.
>>>> How do you explain that something as inferior as Python beat Lisp in
>>>> the market place despite starting 40 years later.
>>> There was no reason to crosspost this here--looking at the original
>>> thread on comp.lang.lisp it seems they were doing a surprisingly good
>>> job discussing the issue.
>>> I'm guessing it's because the fanboy Lispers like Ken Tifton were busy
>>> with a flamewar in another thread (LISP vs PROLOG vs HASKELL).
>>> Carl Banks
>> This is an incredibly important discussion
> 
> It might be an important question but a discussion on Usenet about it
> is utterly useless.
> 
> 
>> and is much weaker because
>> it does not also include Pascal, BASIC, Ada, Oberon and Forth.
> 
> In the same way that a movie is weaker because the director edited out
> the bad scenes.
> 
> 
>> In fact,
>> picking a computer language is the most important discussion in
>> Computer Science and eclipses even P=NP? in significance. I sure hope
>> we can keep this thread going for a few months.
> 
> Please feel free to extend this flame-war along for a few months on
> comp.lang.lisp.  Not here.
> 
> 
> Carl Banks

Uh Carl ... are you familiar with the concept of mocking humor?

-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 01:54:57 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 02:54:57 -0300
Subject: file write IOError Invalid argument
References: <505868.24184.qm@web59308.mail.re1.yahoo.com>
Message-ID: <op.uxcqpvk8x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 16 Jul 2009 17:41:39 -0300, Robert Robert  
<robertrobert93 at yahoo.com> escribi?:

> I am trying to write a binary string to file on a windows network share.  
> I get an IOError. I've read that it is because the file size is too  
> large. I did a type( binaryString) and saw that it was type "str". So I  
> loop through it one by one element and use f.write to write to file, and  
> it worked without any error. However it took a long while to write to  
> file. I was wondering how I could split this binary string into N number  
> of chunks efficiently and write them to file.

some_string[i:i+BLOCK_SIZE]
returns a slice of the original string, starting at position i, with  
length BLOCK_SIZE.

-- 
Gabriel Genellina



From bob.martin at excite.com  Mon Jul 20 02:12:45 2009
From: bob.martin at excite.com (Bob Martin)
Date: Mon, 20 Jul 2009 06:12:45 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<mailman.3405.1248033697.8015.python-list@python.org>
Message-ID: <xVT8m.58560$OO7.36279@text.news.virginmedia.com>

in 121683 20090719 210126 Terry Reedy <tjreedy at udel.edu> wrote:
>Roy Smith wrote:
>> In article <1cethsrrw8h6k$.9ty7j7u7zovn.dlg at 40tude.net>,
>>  Frank Buss <fb at frank-buss.de> wrote:
>>
>>> there is one free unique implementation on the 3 major platforms Linux,
>>> Windows and MacOS X
>>
>> Most people would still consider Solaris to be a "major platform".
>
>?? I do not, but I have no idea what comes in 4th after the other three
>by whatever metric.

I think the OP means "major PC operating systems".  Those with a wider 
knowledge of the computer world would consider IBM's mainframe operating
systems to be deserving of the description "major".


From http  Mon Jul 20 02:13:15 2009
From: http (Paul Rubin)
Date: 19 Jul 2009 23:13:15 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
Message-ID: <7x4ot7rif8.fsf@ruckus.brouhaha.com>

Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:
> Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing 
> to do. It's the right thing to do if you're doing integer maths.

I wonder whether 2/3 => ValueError is preferable.


From martin at v.loewis.de  Mon Jul 20 02:27:20 2009
From: martin at v.loewis.de (=?windows-1252?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Mon, 20 Jul 2009 08:27:20 +0200
Subject: Managing non-ascii filenames in python
In-Reply-To: <60a305de-0552-4f77-9051-d87149d308c7@y10g2000prg.googlegroups.com>
References: <60a305de-0552-4f77-9051-d87149d308c7@y10g2000prg.googlegroups.com>
Message-ID: <4a640e48$0$7445$9b622d9e@news.freenet.de>

> I thought the correct way to do this in python would be to scan the
> dir
> files=os.listdir(os.path.dirname( os.path.realpath( __file__ ) ))
> 
> then print the filenames
> for filename in files:
>   print filename
> 
> but as expected teh filename is not correct - so correct it using the
> file sysytems encoding
> 
>   print filename.decode(sys.getfilesystemencoding())
> 
> But I get
> UnicodeEncodeError: 'charmap' codec can't encode character u'\u2014'
> in position 6: character maps to <undefined>

As a starting point, you shouldn't be using byte-oriented APIs to
access files on Windows; the specific byte-oriented API is os.listdir,
when passed a directory represented as a byte string.

So try:

   dirname = os.path.dirname(os.path.realpath(__file__))
   dirname = dirname.decode(sys.getfilesystemencoding()
   files = os.listdir(dirname)

This should give you the files as Unicode strings.

> I need to be able to write (a representation) to the screen (and I
> don't see why I should not get something as good as DOS shows).

The command window (it's not really DOS anymore) uses the CP_OEMCP
encoding, which is not available in Python. This does all the
transliteration also, so you would have to write an extension module
if you want to get the same transliteration (or try to get to the
OEMCP encoding through ctypes).

If you can live with a simpler transliteration, try

  print filename.encode(sys.stdout.encoding, "replace")

> Write it to an XML file in UTF-8
> 
> and write it to a text file and be able to read it back in.
> Again I was supprised that this was also difficult - it appears that
> the file also wanted ascii.  Should I have to open the file in binary
> for write (I expect so) but then what encoding should I write in?

You need to tell us how precisely you tried to do this. My guess is:
if you now try again, with the filenames being Unicode strings, it
will work fairly well.

Regards,
Martin


From fb at frank-buss.de  Mon Jul 20 02:28:58 2009
From: fb at frank-buss.de (Frank Buss)
Date: Mon, 20 Jul 2009 08:28:58 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<mailman.3405.1248033697.8015.python-list@python.org>
	<xVT8m.58560$OO7.36279@text.news.virginmedia.com>
Message-ID: <1pk5i4u29maii.vcsqz0mmsyy5$.dlg@40tude.net>

Bob Martin wrote:

> I think the OP means "major PC operating systems".  Those with a wider 
> knowledge of the computer world would consider IBM's mainframe operating
> systems to be deserving of the description "major".

Maybe you are right, if you mean big machines. I know mainframes a bit and
there are interesting concepts, like hot-swapping of CPU modules and
mainframes are very reliable. But expensive, too. I know at least one
client, who wants to change it to some cheap Linux boxes, like Google
demonstrates it. If you take care (e.g. Xen virtualization for easier
computer changing and RAID harddisks, if a downtime of some hours might be
ok), it doesn't matter if one PC goes out of order.

But even on IBM mainframes you can install Linux or other Unix systems in
parallel to the usual operating systems for this machines, so except for
special cases, like embedded systems, the most installed and used operating
systems might be Unix-like systems and Windows. But looks like Python even
runs on more native operating systems for mainframes.

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From bob.martin at excite.com  Mon Jul 20 02:40:21 2009
From: bob.martin at excite.com (Bob Martin)
Date: Mon, 20 Jul 2009 06:40:21 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<mailman.3405.1248033697.8015.python-list@python.org>
	<xVT8m.58560$OO7.36279@text.news.virginmedia.com>
	<1pk5i4u29maii.vcsqz0mmsyy5$.dlg@40tude.net>
Message-ID: <pjU8m.58569$OO7.15871@text.news.virginmedia.com>

in 121708 20090720 072858 Frank Buss <fb at frank-buss.de> wrote:
>Bob Martin wrote:
>
>> I think the OP means "major PC operating systems".  Those with a wider
>> knowledge of the computer world would consider IBM's mainframe operating
>> systems to be deserving of the description "major".
>
>Maybe you are right, if you mean big machines. I know mainframes a bit and
>there are interesting concepts, like hot-swapping of CPU modules and
>mainframes are very reliable. But expensive, too. I know at least one
>client, who wants to change it to some cheap Linux boxes, like Google
>demonstrates it. If you take care (e.g. Xen virtualization for easier
>computer changing and RAID harddisks, if a downtime of some hours might be
>ok), it doesn't matter if one PC goes out of order.
>
>But even on IBM mainframes you can install Linux or other Unix systems in
>parallel to the usual operating systems for this machines, so except for
>special cases, like embedded systems, the most installed and used operating
>systems might be Unix-like systems and Windows. But looks like Python even
>runs on more native operating systems for mainframes.

Yes, a "platform" is really the combination of hardware architecture and operating system,
so Linux on Intel and Linux on 390 are different platforms.


From pavlovevidence at gmail.com  Mon Jul 20 03:08:31 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 20 Jul 2009 00:08:31 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com> 
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
	<1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
	<jabdj6-qij.ln1@ozzie.tundraware.com>
Message-ID: <77e91c9e-5487-427d-9300-3ad9015adf51@2g2000prl.googlegroups.com>

On Jul 19, 10:18?pm, Tim Daneliuk <tun... at tundraware.com> wrote:
> Uh Carl ... are you familiar with the concept of mocking humor?

You got me, lip hurts bad. :)


Carl Banks


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 03:29:17 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 04:29:17 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com>
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
Message-ID: <op.uxcu23j6x6zn5v@lepton.softlabbsas.com.ar>

En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac <alan.isaac at gmail.com>  
escribi?:

>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>> def apply2(itr, methodname, *args, **kwargs):
>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>     for item in itr:
>>>         f(item)
>
>
> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>> for obj in objects:
>>     getattr(obj, methodname)(*args, **kwargs)
>
>
> Are there any obvious considerations in choosing
> between those two?

The operator.methodcaller version is faster in my tests for large  
collections, but slightly slower when you have very few elements.

<code>
import operator
import timeit

class X:
   def method(self, x, y, **kw): pass

def apply1(itr, methodname, *args, **kwargs):
     for item in itr:
         getattr(item, methodname)(*args, **kwargs)

def apply2(itr, methodname, *args, **kwargs):
     f = operator.methodcaller(methodname, *args, **kwargs)
     for item in itr:
         f(item)

L=[X() for _ in range(3000)]
apply1(L,'method', 1, 2, foo=3)
apply2(L,'method', 1, 2, foo=3)

timeit.timeit(setup="from __main__ import apply1,apply2,L",  
stmt="apply1(L,'method', 1, 2, foo=3)", number=1000)
timeit.timeit(setup="from __main__ import apply1,apply2,L",  
stmt="apply2(L,'method', 1, 2, foo=3)", number=1000)
</code>

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 20 03:50:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 04:50:15 -0300
Subject: Mechanize not recognized by py2exe
References: <4A60C81F.7080707@comcast.net>
Message-ID: <op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 15:51:11 -0300, Stephen M. Olds <smolds at comcast.net>  
escribi?:

> I have a Python script getData.py that uses Mechanize, and runs fine  
> under the
> interpreter. It was installed using easy_install - and the install  
> seemed to
> indicate it was completed.
>
> The problem is, when I try to compile it using py2exe while in the  
> folder of the
> script, and using the run line command:
>
> python getData.py py2exe
>
> I get the warning: "Import error: No Module named mechanize"...
>
> I checked the environmental path and find the following:
> %SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program  
> Files (x86)\Python;C:\Python25\Lib\site-packages;C:\Program
> Files (x86)\Common Files\Adobe\AGL

The system PATH is irrelevant here - it's only used by Windows to locate  
the Python executable. I don't see a reason to list  
C:\Python25\Lib\site-packages here.
You're mostly interested in sys.path instead (that is, the 'path'  
attribute in the 'sys' Python module)

> I did a search for mechanize and find an egg file in  
> C:\Python25\Lib\site-packages
> named mechanize-0.1.7b-py2.5.
>
> Not really understanding the "egg" thing, what do I have here that needs  
> to be
> done?

I'm not an egg expert either, and I try to avoid them as a plague. But I  
*think* you can delete the .egg and re-install it using easy_install with  
the -Z option.

-- 
Gabriel Genellina



From greg at cosc.canterbury.ac.nz  Mon Jul 20 04:00:14 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Mon, 20 Jul 2009 20:00:14 +1200
Subject: tough-to-explain Python
In-Reply-To: <6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
Message-ID: <7cimf0F27u23eU1@mid.individual.net>

Calroc wrote:

> It may be that flawless software is an unreachable asymptote, like the
> speed of light for matter, but I'm (recently!) convinced that it's a
> goal worthy of exploration and effort.

Seems to me that once you get beyond the toy program
stage and try to apply correctness proving to real
world programming problems, you run up against the
problem of what exactly you mean by "correct".

Once the requirements get beyond a certain level of
complexity, deciding whether the specifications
themselves are correct becomes just as difficult as
deciding whether the program meets them.

Then there's the fact that very often we don't
even know what the exact requirements are, and it's
only by trying to write and use the program that
we discover what they really are -- or at least,
get a better idea of what they are, because the
process is usually iterative, with no clear end
point.

So in theory, correctness proofs are a fine idea,
and might even be doble on a small scale, but the
real world is huge and messy!

> Just because it's unattainable doesn't make it undesirable.  And who
> knows? Maybe the horse will learn to sing.

Striving to find ways of writing less bugs is a
worthy goal, but I think of it more in terms of
adopting patterns of thought and programming that
make it more likely you will write code that does
what you had in mind, rather than a separate
"proof" process that you go through afterwards.

-- 
Greg


From stef.mientki at gmail.com  Mon Jul 20 05:34:09 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Mon, 20 Jul 2009 11:34:09 +0200
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <h40adj$bv6$1@adenine.netfront.net>
References: <mailman.3406.1248034495.8015.python-list@python.org>
	<h40adj$bv6$1@adenine.netfront.net>
Message-ID: <4A643A11.6030109@gmail.com>

thanks Marcus,

Marcus Wanner wrote:
> On 7/19/2009 4:15 PM, Stef Mientki wrote:
>> hello,
>>
>> I'm using Scintilla as a wxPython widget with great pleasure.
>> I now have an application where I want to make notes during a 
>> conversation,
>> but also want to record the speech during that conversation.
>> I'm using Scintilla as a wxPython widget for editing and PyAudio for 
>> the speech recording,
>> until so far everything works fine.
>>
>> Here the problem part:
>> I need to synchronize the typed text with the sound during playback.
>> So if I click somewhere in the sound recording,
>> the line of text, typed that moment should be highlighted.
>> And vise versa, if the cursor in the text is moved and some special 
>> key is pressed,
>> the sound starting 10 or 20seconds earlier should be playbacked.
>>
>> I though of adding bookmarks (because these are fixed in the text), 
>> and keep a list of bookmarks and sound pointers.
>> This idea should work, but there are only 31 bookmarks.
>>
>> Any other suggestions ?
>>
>> thanks,
>> Stef Mientki
> That sounds like a very specialized type of thing, 
Well from an application point of view,
with the current netbooks,
this looks like a perfect tool for any conversation or meeting.
> which only the few people with experience with wxPython, PyAudio, and 
> Scintilla could help you with...
>
I was afraid of that too, so I dropped the question in several places,
and the writer of Scintilla himself came with the perfect answer.

cheers,Stef
> But you might try having a dictionary with notes and associated times, 
> or just give each note a four-digit ID number at the beginning of it 
> when it's entered and use that in the dictionary (to keep keys 
> shorter). Or you could just do a little hack and increase the number 
> of bookmarks allowed (seeing as source is available) :p
>
> Marcus



From sion at viridian.paintbox  Mon Jul 20 05:34:24 2009
From: sion at viridian.paintbox (Sion Arrowsmith)
Date: Mon, 20 Jul 2009 09:34:24 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
	<mailman.3317.1247864411.8015.python-list@python.org>
Message-ID: <ASW8m.3332$Tk2.91@newsfe21.ams2>

Terry Reedy  <tjreedy at udel.edu> wrote:
>Sion Arrowsmith wrote:
>> Jack Diederich  <jackdied at gmail.com> wrote:
>>> It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>>> dicts also raise an error if you try to LT them.
>> Python 2.5.2
>>>>> d1 = dict((str(i), i) for i in range (10))
>>>>> d2 = dict((str(i), i) for i in range (20))
>>>>> d1 < d2
>> True
>Try reversing the definitions of d1 and d2. The dicts are probably being 
>compared by id (address), which is the 2.x CPython default.

Like this?

>>> d1 = dict((str(i), i) for i in range (20))
>>> d2 = dict((str(i), i) for i in range (10))
>>> d1 < d2
False
>>> id(d1) < id(d2)
True

I didn't know that comparison for anything other than equality
defaulted to using id. That really is rather broken, and I'm
glad 3.0 fixed it.

-- 
\S

   under construction



From walkraft at gmail.com  Mon Jul 20 05:57:36 2009
From: walkraft at gmail.com (casebash)
Date: Mon, 20 Jul 2009 02:57:36 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
Message-ID: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>

Hi,

I have searched this list and found out that Python doesn't have a
mutable string class (it had an inefficient one, but this was removed
in 3.0). Are there any libraries outside the core that offer this?

Thanks,

Chris


From vivainio at gmail.com  Mon Jul 20 06:12:25 2009
From: vivainio at gmail.com (Ville Vainio)
Date: Mon, 20 Jul 2009 03:12:25 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() that 
	doesn't block gui event loops
Message-ID: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>

Has anyone implementing something like what the subject line
indicates?

The idea:

To run functions that execute a series of system commands without
blocking the ui, *and* without adding state machine logic.

The syntax would be something like:

def work():

  showstatus("building")
  r = yield runshell("make")
  showstatus("installing")
  r = yield runshell("make install")
  showstatus("Success")

mygui.startwork(work)
# returns immediately, runs work() gradually in the background.


The catch is that showstatus() would need to be run in the mainloop,
so running the whole thing in a thread is a no-go.

I imagine runshell() would be implemented in terms of QProcess, or
subprocess.Popen/os.system and a worker thread.

Anyone done this already, or do I have to roll my own?


From vivainio at gmail.com  Mon Jul 20 06:14:35 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Mon, 20 Jul 2009 03:14:35 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <9600897a-100c-4907-826d-0d700cef6880@r2g2000yqm.googlegroups.com>

On Jul 20, 1:12?pm, Ville Vainio <vivai... at gmail.com> wrote:

> Has anyone implementing something like what the subject line

ImplentED.

I don't think this is that hard to do in the first place, but a
"generic" solution that can be easily tuned for different gui
mainloops would be nice.


From pavlovevidence at gmail.com  Mon Jul 20 06:26:09 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 20 Jul 2009 03:26:09 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <cb66436c-0748-4804-94a6-feb846093d06@v37g2000prg.googlegroups.com>

On Jul 20, 2:57?am, casebash <walkr... at gmail.com> wrote:
> Hi,
>
> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

I just did a brief search on Python Packaging Index (pypi.python.org)
and saw nothing.  You might have better luck.

I suspect there is not a mutable string class partly because there is
little demand, partly because it'd be hard to make an object that is
usable everywhere a string is.  For instance, a third-party string
object might not work with the re module.

The core does have some classes that are kind of like strings but
mutable.  The array module can create mutable arrays of characters
which are somewhat like strings.  Depending on your use case some
other things might suffice (such as mmap,  io.StringIO, or even a list
of characters).


Carl Banks


From vivainio at gmail.com  Mon Jul 20 06:28:33 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Mon, 20 Jul 2009 03:28:33 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <ffdab149-c5bb-404b-8a8b-eaf1fb4fe91c@w41g2000yqb.googlegroups.com>

On Jul 20, 1:12?pm, Ville Vainio <vivai... at gmail.com> wrote:

> I imagine runshell() would be implemented in terms of QProcess, or
> subprocess.Popen/os.system and a worker thread.

Actually, the problem is that of general serialization of worker
thread operations. That is, it could be something akin to:

res = yield run_in_thread(lambda : os.system('make'))

run_in_thread would basically grab a worked thread, execute the
callable, and allow the generator to proceed after the thread is done.
Now, the only thing to do is the "generator dispatcher" in gui
mainloop that finds the correct generator and makes it proceed...


From ben+python at benfinney.id.au  Mon Jul 20 07:08:22 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Mon, 20 Jul 2009 21:08:22 +1000
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <87r5wba9y1.fsf@benfinney.id.au>

casebash <walkraft at gmail.com> writes:

> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

A mutable string would not (AFAICT) be usefully implementable as a
subclass of the built-in string types. So even if such a type existed,
it would not be useable with all the functionality that works with
strings.

What is it you're trying to do that makes you search for a mutable
string type? It's likely that a better approach can be found.

-- 
 \     ?As scarce as truth is, the supply has always been in excess of |
  `\                                       the demand.? ?Josh Billings |
_o__)                                                                  |
Ben Finney


From sjmachin at lexicon.net  Mon Jul 20 07:24:06 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 04:24:06 -0700 (PDT)
Subject: On out-of-date Python Applications
References: <mailman.3387.1247990649.8015.python-list@python.org> 
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com> 
	<4A632C9D.2010303@it.uu.se>
	<mailman.3397.1248018457.8015.python-list@python.org>
Message-ID: <e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>

On Jul 20, 1:47?am, John Machin <sjmac... at lexicon.net> wrote:
> On 20/07/2009 12:24 AM, Virgil Stokes wrote:
> > John Machin wrote:
> >> On Jul 19, 6:04 pm, Virgil Stokes <v... at it.uu.se> wrote:
> >>> I am not a heavy user of Python; but, I do work with it and some of its
> >>> application packages (e.g. PyODE), in an academic setting.
> >>> Many of these applications packages have a Windows installer which
> >>> usually works fine. However, I also try to keep up with the latest
> >>> release of Python, and this is where I often have problems. That is, the
> >>> latest Windows installer provided for some of these applications will
> >>> not install on the latest version of Python.
> > Actually John,
> > My question was about the more general case --- how to help with
> > upgrading applications; but, I will try to address your email.
> >> Otherwise: What does "will not install" mean?
> > This means that when the Windows installer is executed it informs you
> > that you do not have a match between the application and the Python that
> > it finds on your Windows PC. You can easily find this out for yourself
> > by trying to install PyODE on a Windows platform with a Python version
> > later than 2.5.x.
> >> Are these pure Python
> >> packages or do they include C extensions (binary (pyd) or source?)?
> > Obviously, this depends on the application. In the particular case that
> > I mentioned (PyODE) I believe that there is a mix of C binaries and
> > Python code.
> >> At
> >> what stage of the installation does the installation fail?
> > In the initial stages.
> >> With what
> >> error message(s)?
> > In one specific case, the message is (paraphrasing) "You do not have
> > Python 2.5 installed" --- the installation is then aborted.
> >> With what versions of Python?
>
> > I have only Python 2.6.2 on my home Windows Vista PC and PyODE does not
> > have a Windows Installer for Python 2.6.
>
> >>> I do understand that there can be a time lag between the release of
> >>> Python applications and the latest Python. I also appreciate the work of
> >>> the people that are responsible for these applications.
>
> >>> My question is --- Is there anything I, as a user of an application
> >>> package that is out-of-date with respect to the latest Python, can do to
> >>> help in this process of bringing an application ?up-to-date?
> > Note, again John, my question was about how I might assist (help) with
> > the updating of applications;
>
> Your answers have been very helpful in determining exactly what your
> problem is; thank you.
>
> > but, thank you for your interest in this.
> > Perhaps, only the owner/responsible programmer for the application can
> > create a Windows installer,
>
> Given a source distribution, a suitable C++ compiler, and the suspension
> of Murphy's Law, anyone should be able to (a) install it on their own
> machine (b) make a Windows installer.
>
> > or perhaps others could assist with this ---
>
> Perhaps indeed ...
>
> > this is what my question was about. I would be glad to assist if
> > possible :-)
>
> Suggestions:
>
> (1) contact the pyODE maintainer and ask, or check out the project's
> forums on sourceforge
>
> (2) if you have a C++ compiler on your Windows box: get the source
> distribution, unpack it, ensure that the ODE_BASE in the setup.py points
> to your (existing) ODE 0.7 installation, do
> ? ? ?\python26\python setup.py install
> and stand well back.
>
> I have just tried this and got a ton of warnings from the compile and 3
> errors from the link:
>
> build\lib.win32-2.6\ode.pyd : fatal error LNK1120: 3 unresolved externals
> error: command '"C:\Program Files\Microsoft Visual Studio
> 9.0\VC\BIN\link.exe"' failed with exit status 1120

Update: The problem is evidently with the lib(s) available with ODE
0.7 (or 0.8 -- there are conflicting stories about which one to use
with PyODE); they were compiled with VS2003 AFAICT and the complained-
of symbols are not supplied by VS2009 which is what I'm using to try
and build PyODE for Python 2.6 .

The next step would be to try to compile ODE 0.7 or 0.8 with VS9 --
however this would require "project files" for ODE for VS9, and there
aren't any on the ODE website; it has only those for VS3 and VS5.

As all I know about VS9 is that somewhere inside the ferschlugginer
100 Mb download there's a C compiler that does the right thing when
distutils pushes its button, I'm going to have to punt this back to
you to follow up on suggestion (1) ... skip asking the pyODE
maintainer (last heard saying little time available and he wasn't
even /using/ pyODE any more); try asking on the pyODE and ODE mailing-
lists has anyone contemplated a Python 2.6 / win32 / VS 2009 build of
pyODE.

Cheers,
John


From sjmachin at lexicon.net  Mon Jul 20 07:30:12 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 04:30:12 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
Message-ID: <47ab4ab6-d8c8-4997-8963-ac41b00dd10f@y10g2000prg.googlegroups.com>

On Jul 20, 9:08?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> casebash <walkr... at gmail.com> writes:
> > I have searched this list and found out that Python doesn't have a
> > mutable string class (it had an inefficient one, but this was removed
> > in 3.0). Are there any libraries outside the core that offer this?
>
> A mutable string would not (AFAICT) be usefully implementable as a
> subclass of the built-in string types. So even if such a type existed,
> it would not be useable with all the functionality that works with
> strings.
>
> What is it you're trying to do that makes you search for a mutable
> string type? It's likely that a better approach can be found.
>

OK, I'll bite: where does the Python 3.x bytearray type fit into your
taxonomy? At first glance it appears to be mutable and have a fair
swag of functionality.


From drobinow at gmail.com  Mon Jul 20 07:46:12 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 20 Jul 2009 07:46:12 -0400
Subject: On out-of-date Python Applications
In-Reply-To: <e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
References: <mailman.3387.1247990649.8015.python-list@python.org>
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>
	<4A632C9D.2010303@it.uu.se>
	<mailman.3397.1248018457.8015.python-list@python.org>
	<e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
Message-ID: <4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>

On Mon, Jul 20, 2009 at 7:24 AM, John Machin<sjmachin at lexicon.net> wrote:
...
> The next step would be to try to compile ODE 0.7 or 0.8 with VS9 --
> however this would require "project files" for ODE for VS9, and there
> aren't any on the ODE website; it has only those for VS3 and VS5.
>
 The ODE site is a mess.
Go to http://www.ode.org/svn.html  and click on:   Instructions for
accessing the repository
 Scroll down to the section "Building with Premake"
 (Note that there is no directory "ode/build" -- you want the "build"
directory, which contains premake4.exe)
I used "premake4 --with-demos --with-tests vs2008"
I have successfully compiled ode-0.11.1 using these instructions. I
have not yet run the tests or demos or tried to compile PyODE.


From wilk at flibuste.net  Mon Jul 20 07:56:49 2009
From: wilk at flibuste.net (William Dode)
Date: 20 Jul 2009 11:56:49 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
Message-ID: <4a645b81$0$12974$426a74cc@news.free.fr>

On 19-07-2009, Mark Dufour wrote:
> Hi all,
>
> I have just released version 0.2 of Shed Skin, an experimental
> (restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).

I just tested it with a litle game, to find the places of horse on 
a board 5x5. The result is :

c 5s
gcj 7s
java 7s
shedskin 8s
python + psyco 18s
cython avec malloc *int 18s
cython 55s avec [] python
python 303s (5m3s)

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From Lacrima.Maxim at gmail.com  Mon Jul 20 08:20:26 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Mon, 20 Jul 2009 05:20:26 -0700 (PDT)
Subject: Design question.
Message-ID: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>

Hello!

I am newbie in python and I have really simple question, but I need
your advice to know how to do best.
I need to store a number of dictionaries in certain place. I've
decided to store them in a separate module.
Like this:
dicts.py
-----------------------
dict1 = {....}
dict2 = {....}
dict3 = {....}

Then, when I need any dictionary, I can access it:
import dicts
dicts.dict1

Is it a good practice? Or should I store them as class attributes or
anything else?

Thanks in advance.

With regards, Max
(sorry if my English isn't very proper)


From magobin at gmail.com  Mon Jul 20 08:28:27 2009
From: magobin at gmail.com (Alex)
Date: Mon, 20 Jul 2009 05:28:27 -0700 (PDT)
Subject: A lot of problem with pygame.mixer module!
Message-ID: <a06c2c1c-7727-46d4-8876-55ffe9543493@d4g2000yqa.googlegroups.com>

hi at all,
As email object I 'm not be able to run my program when compiled with
py2exe.
Everythink  works fine until I try to make an exe.
After that, it crash and in the log:

C:\dist\sponge.exe:97: RuntimeWarning: use mixer: DLL load failed: The
specified module could not be found.
Traceback (most recent call last):
  File "sponge.py", line 97, in <module>
  File "pygame\__init__.pyo", line 70, in __getattr__
NotImplementedError: mixer module not available

The code about pygame.mixer is only:

pygame.mixer.init()
music = pygame.mixer.Sound("popcorn.ogg")
music.play()

in the dist folder there is SDL_mixer.dll so...HOW can I solve this
problem ??
thanks in advance
Alex
Below my setup.py

# py2exe setup program
from distutils.core import setup
import py2exe
import pygame
from modulefinder import Module
#from pygame import mixer
import ImageGrab
import sys
import os
import Tkinter
import glob, shutil
sys.argv.append("py2exe")

VERSION = '1.0'
AUTHOR_NAME = 'Your Name'
AUTHOR_EMAIL = 'your_email at somewhere.com'
AUTHOR_URL = "http://www.urlofyourgamesite.com/"
PRODUCT_NAME = "Sponge"
SCRIPT_MAIN = 'sponge.py'
VERSIONSTRING = PRODUCT_NAME + " ALPHA " + VERSION
ICONFILE = 'icon.ico'

# Remove the build tree on exit automatically
REMOVE_BUILD_ON_EXIT = True

if os.path.exists('dist/'): shutil.rmtree('dist/')

extra_files = [ ("",[ICONFILE,'WinLockDll.dll','popcorn.ogg']),
                   #("data",glob.glob(os.path.join('data','*.dat'))),
                   #("gfx",glob.glob(os.path.join('gfx','*.jpg'))),
                   #("gfx",glob.glob(os.path.join('gfx','*.png'))),
                   ("fonts",glob.glob(os.path.join('fonts','*.ttf'))),
                   ("music",glob.glob(os.path.join('music','*.ogg')))]
                   #("snd",glob.glob(os.path.join('snd','*.wav')))]

# List of all modules to automatically exclude from distribution build
# This gets rid of extra modules that aren't necessary for proper
functioning of app
# You should only put things in this list if you know exactly what you
DON'T need
# This has the benefit of drastically reducing the size of your dist

MODULE_EXCLUDES =[
'email',
'AppKit',
'Foundation',
'bdb',
'difflib',
'tcl',
#'Tkinter',
#'Tkconstants',
'curses',
'distutils',
'setuptools',
'urllib',
'urllib2',
'urlparse',
'BaseHTTPServer',
'_LWPCookieJar',
'_MozillaCookieJar',
'ftplib',
'gopherlib',
'_ssl',
'htmllib',
'httplib',
'mimetools',
'mimetypes',
'rfc822',
'tty',
'webbrowser',
'socket',
'hashlib',
#'base64',
'compiler',
'pydoc'
]

INCLUDE_STUFF = ['encodings',"encodings.latin_1"]

setup(windows=[
             {'script': SCRIPT_MAIN,
               'other_resources': [(u"VERSIONTAG",1,VERSIONSTRING)],
               'icon_resources': [(1,ICONFILE)]}],
         options = {"py2exe": {
                             "optimize": 2,
                             "includes": INCLUDE_STUFF,
                             "compressed": 1,
                             "ascii": 1,
                             #"bundle_files": 1,
                             "ignores":
['tcl','AppKit','Numeric','Foundation'],
                             "excludes": MODULE_EXCLUDES} },
          name = PRODUCT_NAME,
          version = VERSION,
          data_files = extra_files,
          #zipfile = None,
          author = AUTHOR_NAME,
          author_email = AUTHOR_EMAIL,
          url = AUTHOR_URL)

# Create the /save folder for inclusion with the installer
#shutil.copytree('save','dist/save')

#if os.path.exists('dist/tcl'): shutil.rmtree('dist/tcl')

# Remove the build tree
if REMOVE_BUILD_ON_EXIT:
     shutil.rmtree('build/')

if os.path.exists('dist/tcl84.dll'): os.unlink('dist/tcl84.dll')
if os.path.exists('dist/tk84.dll'): os.unlink('dist/tk84.dll')


From vippstar at gmail.com  Mon Jul 20 08:29:40 2009
From: vippstar at gmail.com (vippstar)
Date: Mon, 20 Jul 2009 05:29:40 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
Message-ID: <fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>

On Jul 20, 9:13?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Steven D'Aprano <ste... at REMOVE.THIS.cybersource.com.au> writes:
> > Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing
> > to do. It's the right thing to do if you're doing integer maths.
>
> I wonder whether 2/3 => ValueError is preferable.

Not all software wants this. It shouldn't be part of the language but
rather part of your code if you need such a feature. (for instance, to
distinguish between 2/3 and divisions with 0 dividend).


From deets at nospam.web.de  Mon Jul 20 08:31:15 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 20 Jul 2009 14:31:15 +0200
Subject: Design question.
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
Message-ID: <7cj63mF285spnU1@mid.uni-berlin.de>

Lacrima wrote:

> Hello!
> 
> I am newbie in python and I have really simple question, but I need
> your advice to know how to do best.
> I need to store a number of dictionaries in certain place. I've
> decided to store them in a separate module.
> Like this:
> dicts.py
> -----------------------
> dict1 = {....}
> dict2 = {....}
> dict3 = {....}
> 
> Then, when I need any dictionary, I can access it:
> import dicts
> dicts.dict1
> 
> Is it a good practice? Or should I store them as class attributes or
> anything else?

It's perfectly fine to use dictionaries as module-level objects for storing
e.g. configuration-data.

OTOH it's also fine to do so as class-attributes. Choosing one over the
other has a lot to do with the actual problem you are working on. 


Diez


From ndbecker2 at gmail.com  Mon Jul 20 08:39:28 2009
From: ndbecker2 at gmail.com (Neal Becker)
Date: Mon, 20 Jul 2009 08:39:28 -0400
Subject: proposal: add setresuid() system call to python
References: <20090717200141.GI6065@subspacefield.org>
	<148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>
Message-ID: <h41oi0$v1$1@ger.gmane.org>

Mahmoud Abdelkader wrote:

> Why don't you write a python extension module? This is a perfect
> opportunity for that.
> 
I think having a module just for one system call is a bit silly.  Why not 
add to os module?




From miheavner at gmail.com  Mon Jul 20 08:41:02 2009
From: miheavner at gmail.com (mheavner)
Date: Mon, 20 Jul 2009 05:41:02 -0700 (PDT)
Subject: Persistent variable in subprocess using multiprocessing?
References: <d8d5acb7-583c-406a-a2ae-c50c71bac49f@h21g2000yqa.googlegroups.com>
	<m2ocrkvm1x.fsf@cs.uu.nl>
	<93ef749c-fd54-4ab9-9a67-fda5068051d1@k19g2000yqn.googlegroups.com>
	<m2iqhru34c.fsf@cs.uu.nl>
Message-ID: <b893725d-4dea-4b16-90c5-d1e34e374b1b@h31g2000yqd.googlegroups.com>

Piet,

The situation is 1a of your listed options, however my issue was
solved. I was stopping the subprocesses from consuming more data at
each iteration which led to the data being lost since the subprocess
worker function would then end - I now keep them alive across
iterations.

Thanks for your help, I'm new to the multiprocessing module and this
was very helpful!

On Jul 17, 4:26?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> There is stil something not clear in your description.
>
> >m> I'm using multiprocessing to spawn several subprocesses, each of which
> >m> uses a very large data structure (making it impractical to pass it via
> >m> pipes / pickling). I need to allocate this structure once when the
> >m> process is created and have it remain in memory for the duration of
> >m> the process.
>
> I have read this as that every subprocess has its own large
> data structure and that there is no connection between these.
>
> But seeing where the discussion is going I guess there might be
> different interpretations. So can you enlighten us how the situation is?
>
> 1. Each subprocess has a copy of a data structure that is prepared by the
> ? ?master process. Therefore you want it to be passed by the fork
> ? ?1a. the data structure is constant i.e. the subprocess doesn't change it
> ? ?1b. the subprocess makes changes in its copy
> 2. Each subprocess has a seperate data structure not equal to the others
> 3. Something else.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org



From Lacrima.Maxim at gmail.com  Mon Jul 20 08:44:22 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Mon, 20 Jul 2009 05:44:22 -0700 (PDT)
Subject: Design question.
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
	<7cj63mF285spnU1@mid.uni-berlin.de>
Message-ID: <825d0aae-3147-4f81-8c82-fa86e4b777df@c29g2000yqd.googlegroups.com>

On Jul 20, 3:31?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Lacrima wrote:
> > Hello!
>
> > I am newbie in python and I have really simple question, but I need
> > your advice to know how to do best.
> > I need to store a number of dictionaries in certain place. I've
> > decided to store them in a separate module.
> > Like this:
> > dicts.py
> > -----------------------
> > dict1 = {....}
> > dict2 = {....}
> > dict3 = {....}
>
> > Then, when I need any dictionary, I can access it:
> > import dicts
> > dicts.dict1
>
> > Is it a good practice? Or should I store them as class attributes or
> > anything else?
>
> It's perfectly fine to use dictionaries as module-level objects for storing
> e.g. configuration-data.
>
> OTOH it's also fine to do so as class-attributes. Choosing one over the
> other has a lot to do with the actual problem you are working on.
>
> Diez

Hi!

Thank you very much for your so soon reply!

With regards,
Max


From jeanmichel at sequans.com  Mon Jul 20 09:05:13 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 20 Jul 2009 15:05:13 +0200
Subject: Design question.
In-Reply-To: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
Message-ID: <4A646B89.7060103@sequans.com>

Lacrima wrote:
> Hello!
>
> I am newbie in python and I have really simple question, but I need
> your advice to know how to do best.
> I need to store a number of dictionaries in certain place. I've
> decided to store them in a separate module.
> Like this:
> dicts.py
> -----------------------
> dict1 = {....}
> dict2 = {....}
> dict3 = {....}
>
> Then, when I need any dictionary, I can access it:
> import dicts
> dicts.dict1
>
> Is it a good practice? Or should I store them as class attributes or
> anything else?
>
> Thanks in advance.
>
> With regards, Max
> (sorry if my English isn't very proper)
>   
Defining dict as a module attribute ic correct, but try to answer the 
following question:

Is dict1 an attribute/property/declension of the object/entity defined 
by the module dicts ?
If yes, then your design is correct.

An correct example:
fruits.py
------------
apple = {}
banana = {}

An incorrect one:
fruit.py
-----------
apple={}
bicycle={}

Basically, the rule is very straightforward, set your dict as a module 
attribute only if its one of its attribute (very nice paraphrase !)
Most of people (including me) tend to have a  module, where they put 
everything they have no idea about their location. This is a bad habit 
and result from a uncontrolled/undocumented design. Usually documenting 
objects in such modules is really painful.

Your proposal is fine from a python syntax point of view. I can't tell 
of your design with names like (dicts.py and dict1,dict2) hoping you do 
not intend to name them that way.

JM


From deets at nospam.web.de  Mon Jul 20 09:10:17 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 20 Jul 2009 15:10:17 +0200
Subject: proposal: add setresuid() system call to python
References: <20090717200141.GI6065@subspacefield.org>
	<148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>
	<mailman.3421.1248093585.8015.python-list@python.org>
Message-ID: <7cj89qF27mfrjU1@mid.uni-berlin.de>

Neal Becker wrote:


again with his notorious gmane.comp.python.general group that doesn't work
for any decent news-reader.....


> Mahmoud Abdelkader wrote:
> 
>> Why don't you write a python extension module? This is a perfect
>> opportunity for that.
>> 
> I think having a module just for one system call is a bit silly.  Why not
> add to os module?

While I do agree that it's an omission, it is easy enough to get it yourself
using ctypes:


from ctypes import *
from ctypes.util import find_library

clib = CDLL(find_library("c"))
# this might be different on 64bit
__uid_t = c_uint

_setresuid = clib.setresuid
_setresuid.argtypes = [__uid_t, __uid_t, __uid_t]
_setresuid.restype = c_int

def setresuid(ruid, euid, suid):
    return _setresuid(__uid_t(ruid), __uid_t(euid), __uid_t(suid))


print setresuid(1000, 1000, 1000) # returns 0 for me
print setresuid(1001, 1001, 1001) # fails.

Diez


From stefan_ml at behnel.de  Mon Jul 20 09:22:02 2009
From: stefan_ml at behnel.de (Stefan Behnel)
Date: Mon, 20 Jul 2009 15:22:02 +0200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <4a645b81$0$12974$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <4a646f7b$0$31869$9b4e6d93@newsspool3.arcor-online.net>

William Dode wrote:
> On 19-07-2009, Mark Dufour wrote:
>> I have just released version 0.2 of Shed Skin, an experimental
>> (restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).
> 
> I just tested it with a litle game, to find the places of horse on 
> a board 5x5. The result is :
>
> [...]
> shedskin 8s
> python + psyco 18s
> cython avec malloc *int 18s
> cython 55s avec [] python
> python 303s (5m3s)

Note that both Psyco and Cython make a lot less assumptions about Python
code than Shed Skin does. Psyco has the advantage of just needing to jump
in when it finds out that it can help, so it's the most broadly compatible
of the three. But Cython also supports quite a large corpus of dynamic
Python code by now. Shed Skin has a lot of restrictions, many of which are
by design. It's not intended to compile dynamic code, and I think that's a
good thing, because that's what makes it fast for the code that it
supports. Getting the same speed in Cython requires a bit more explicit
typing, simply because Cython does not assume these restrictions.

I think that all three have their raison d'?tre, and it currently looks
like all three are there to stay and to keep growing better. And I'm also
happy to read that some optimisations jump from one to the other. ;)

Stefan


From Lacrima.Maxim at gmail.com  Mon Jul 20 09:42:23 2009
From: Lacrima.Maxim at gmail.com (Lacrima)
Date: Mon, 20 Jul 2009 06:42:23 -0700 (PDT)
Subject: Design question.
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
	<mailman.3423.1248095131.8015.python-list@python.org>
Message-ID: <68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>

On Jul 20, 4:05?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> Lacrima wrote:
> > Hello!
>
> > I am newbie in python and I have really simple question, but I need
> > your advice to know how to do best.
> > I need to store a number of dictionaries in certain place. I've
> > decided to store them in a separate module.
> > Like this:
> > dicts.py
> > -----------------------
> > dict1 = {....}
> > dict2 = {....}
> > dict3 = {....}
>
> > Then, when I need any dictionary, I can access it:
> > import dicts
> > dicts.dict1
>
> > Is it a good practice? Or should I store them as class attributes or
> > anything else?
>
> > Thanks in advance.
>
> > With regards, Max
> > (sorry if my English isn't very proper)
>
> Defining dict as a module attribute ic correct, but try to answer the
> following question:
>
> Is dict1 an attribute/property/declension of the object/entity defined
> by the module dicts ?
> If yes, then your design is correct.
>
> An correct example:
> fruits.py
> ------------
> apple = {}
> banana = {}
>
> An incorrect one:
> fruit.py
> -----------
> apple={}
> bicycle={}
>
> Basically, the rule is very straightforward, set your dict as a module
> attribute only if its one of its attribute (very nice paraphrase !)
> Most of people (including me) tend to have a ?module, where they put
> everything they have no idea about their location. This is a bad habit
> and result from a uncontrolled/undocumented design. Usually documenting
> objects in such modules is really painful.
>
> Your proposal is fine from a python syntax point of view. I can't tell
> of your design with names like (dicts.py and dict1,dict2) hoping you do
> not intend to name them that way.
>
> JM

Hi, Jean-Michel!

Thanks for your answer.
I am not going to have names like dicts.py and dict1,dict2. That was
just example. I wanted to know if it is correct to have dictionaries
on a module level. Now I know that this is correct. I want to collect
in one module a number of dictionaries, every of which describes a
separate web service. And my function in another module will import
required dictionary, depending on what web service should be used.
Thanks again for the help.

With regards,
Max.
(sorry if my English isn't very proper)


From gerard.blais at gmail.com  Mon Jul 20 09:47:54 2009
From: gerard.blais at gmail.com (Gerry)
Date: Mon, 20 Jul 2009 06:47:54 -0700 (PDT)
Subject: win32api install problem
Message-ID: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>

I'm running Python 2.6 under XP.

I've installed Windows 32 extensions for Python 2.6 version 1.4
(pywin32-214.win32-py2.6.exe).

But If I try to import win32api, I get:

  File "C:\python_projects\euler\driveletters.py", line 1, in <module>
    import win32api
ImportError: DLL load failed: The specified module could not be found.

\Python26\Lib\site-packages has:

03/23/2009  08:35 AM    <DIR>          win32
07/20/2009  09:08 AM    <DIR>          win32com
02/18/2009  01:21 PM    <DIR>          win32comext

Can anyone offer a suggestion?

Thanks,

Gerry




From mail at timgolden.me.uk  Mon Jul 20 09:57:56 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 20 Jul 2009 14:57:56 +0100
Subject: win32api install problem
In-Reply-To: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
Message-ID: <4A6477E4.3030808@timgolden.me.uk>

Gerry wrote:
> I'm running Python 2.6 under XP.
> 
> I've installed Windows 32 extensions for Python 2.6 version 1.4
> (pywin32-214.win32-py2.6.exe).
> 
> But If I try to import win32api, I get:
> 
>   File "C:\python_projects\euler\driveletters.py", line 1, in <module>
>     import win32api
> ImportError: DLL load failed: The specified module could not be found.

Used to be you'd get this error if you installed as a
non-admin user. Don't know if that's still an issue.
Possibility?

TJG


From dtgeadamo at yahoo.com  Mon Jul 20 09:57:57 2009
From: dtgeadamo at yahoo.com (mistersexy)
Date: Mon, 20 Jul 2009 06:57:57 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService 
	Account
Message-ID: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>

I am trying to create a Windows service in Python using pywin32. I do
not want this service to run under a user account. I want this service
to be able to run as a LocalService, NetworkService and the like. How
do I specify this using the win32 library? Thanks, everyone.


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 20 10:00:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 20 Jul 2009 14:00:30 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
	<mailman.3317.1247864411.8015.python-list@python.org>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
Message-ID: <02746997$0$5185$c3e8da3@news.astraweb.com>

On Mon, 20 Jul 2009 09:34:24 +0000, Sion Arrowsmith wrote:

> Terry Reedy  <tjreedy at udel.edu> wrote:
>>Sion Arrowsmith wrote:
>>> Jack Diederich  <jackdied at gmail.com> wrote:
>>>> It isn't an OrderedDict thing, it is a comparison thing.  Two regular
>>>> dicts also raise an error if you try to LT them.
>>> Python 2.5.2
>>>>>> d1 = dict((str(i), i) for i in range (10)) d2 = dict((str(i), i)
>>>>>> for i in range (20)) d1 < d2
>>> True
>>Try reversing the definitions of d1 and d2. The dicts are probably being
>>compared by id (address), which is the 2.x CPython default.
> 
> Like this?
> 
>>>> d1 = dict((str(i), i) for i in range (20)) 
>>>> d2 = dict((str(i), i) for i in range (10))
>>>> d1 < d2
> False
>>>> id(d1) < id(d2)
> True
> 
> I didn't know that comparison for anything other than equality defaulted
> to using id. That really is rather broken, and I'm glad 3.0 fixed it.


I don't think comparisons other than equality use id. That would be 
rather insane. If anyone can demonstrate such comparisons in a built-in 
or standard library class, I'd like to see it.


For the record, dicts have been comparable with < and > since at least 
Python 1.5:

$ python1.5
Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
4.1.2-27)] on linux2
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>
>>> {1: 'a', 2: 'b'} < {2: 'b', 3: 'a'}
1


Reading the docs:

http://docs.python.org/library/stdtypes.html#comparisons
http://docs.python.org/library/stdtypes.html#mapping-types-dict

I can only suggest that dicts compare in an arbitrary but consistent 
fashion. What that is based on, I don't know, but based on some very 
limited testing, I'd guess it is like this:

If the two dicts have unequal length, the longer dict compares greater 
than the shorter dict.

If the two dicts are equal in length, (key, item) pairs are compared, 
probably in lexicographic order, because the order of insertion of keys 
doesn't appear to matter.


-- 
Steven


From mail at timgolden.me.uk  Mon Jul 20 10:03:14 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 20 Jul 2009 15:03:14 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
Message-ID: <4A647922.4080908@timgolden.me.uk>

mistersexy wrote:
> I am trying to create a Windows service in Python using pywin32. I do
> not want this service to run under a user account. I want this service
> to be able to run as a LocalService, NetworkService and the like. How
> do I specify this using the win32 library? Thanks, everyone.

When you "install" the service, using the HandleCommandLine
option, specify --username= and --password options.

TJG


From nyamatongwe+thunder at gmail.com  Mon Jul 20 10:05:33 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Mon, 20 Jul 2009 14:05:33 GMT
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>

casebash:

> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

   I wrote a gap buffer implementation for Python 2.5 allowing
character, unicode character and integer elements.

http://code.google.com/p/gapbuffer/

   Its not seen much use or any maintenance so is unlikely to work with
Python 3.x.

   Neil


From hniksic at xemacs.org  Mon Jul 20 10:10:35 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Mon, 20 Jul 2009 16:10:35 +0200
Subject: proposal: add setresuid() system call to python
References: <20090717200141.GI6065@subspacefield.org>
	<148918f0907171315i4ed5b274v77581a43c4464f8f@mail.gmail.com>
	<mailman.3421.1248093585.8015.python-list@python.org>
	<7cj89qF27mfrjU1@mid.uni-berlin.de>
Message-ID: <877hy38mxw.fsf@busola.homelinux.net>

"Diez B. Roggisch" <deets at nospam.web.de> writes:

To emulate the os-module-type calls, it's better to raise exceptions
than return negative values:

> def setresuid(ruid, euid, suid):
>     return _setresuid(__uid_t(ruid), __uid_t(euid), __uid_t(suid))

def setresuid(ruid, euid, suid):
    res = _setresuid(__uid_t(ruid), __uid_t(euid), __uid_t(suid))
    if res < 0:
        raise OSError('[Errno %d] %s' % (os.errno, errno.strerror(os.errno)))


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 20 10:21:15 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 20 Jul 2009 14:21:15 GMT
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
Message-ID: <02746e73$0$5185$c3e8da3@news.astraweb.com>

On Mon, 20 Jul 2009 21:08:22 +1000, Ben Finney wrote:

> casebash <walkraft at gmail.com> writes:
> 
>> I have searched this list and found out that Python doesn't have a
>> mutable string class (it had an inefficient one, but this was removed
>> in 3.0). Are there any libraries outside the core that offer this?
> 
> A mutable string would not (AFAICT) be usefully implementable as a
> subclass of the built-in string types. So even if such a type existed,
> it would not be useable with all the functionality that works with
> strings.

If applications ignore duck-typing and do isinstance(value, str), it's 
arguably the application and not the value that is broken.

Besides, with the new __isinstance__ method, surely such a mutable string 
could claim to be an instance of string without needing to inherit from 
string?


> What is it you're trying to do that makes you search for a mutable
> string type? It's likely that a better approach can be found.

When dealing with very large strings, it is wasteful to have to duplicate 
the entire string just to mutate a single character.

However, when dealing with very large strings, it's arguably better to 
use the rope data structure instead.


http://en.wikipedia.org/wiki/Rope_(computer_science)



-- 
Steven


From invalid at invalid  Mon Jul 20 10:59:17 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 20 Jul 2009 09:59:17 -0500
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<c7b7ac6f-aa4c-4153-b03a-17744d63afa9@d4g2000prc.googlegroups.com>
	<lqmcj6-qij.ln1@ozzie.tundraware.com>
	<1410bb2c-e37f-445b-9fe4-9c4443ad5592@g1g2000pra.googlegroups.com>
	<jabdj6-qij.ln1@ozzie.tundraware.com>
Message-ID: <G_KdnezoObjYG_nXnZ2dnUVZ_vKdnZ2d@posted.visi>

On 2009-07-20, Tim Daneliuk <tundra at tundraware.com> wrote:

>>> In fact, picking a computer language is the most important
>>> discussion in Computer Science and eclipses even P=NP? in
>>> significance. I sure hope we can keep this thread going for a
>>> few months.
>> 
>> Please feel free to extend this flame-war along for a few
>> months on comp.lang.lisp.  Not here.
>
> Uh Carl ... are you familiar with the concept of mocking humor?

Irony on Usenet: always a bit of a gamble...

-- 
Grant Edwards                   grante             Yow! Vote for ME -- I'm
                                  at               well-tapered, half-cocked,
                               visi.com            ill-conceived and
                                                   TAX-DEFERRED!


From craig1.boyd at citi.com  Mon Jul 20 11:09:47 2009
From: craig1.boyd at citi.com (Boyd, Craig1 )
Date: Mon, 20 Jul 2009 10:09:47 -0500
Subject: Auto-generate GUI from a database table structure
Message-ID: <55660F9659966544BBA3AE14CE5D278D01243B8E04@exgtmb08.nam.nsroot.net>

Hello All,

I am REALLY new to python and still trying to figure a lot of this stuff out.
I am trying to write a couple screens to update three or four database tables on Oracle 10g and I was wondering if there was a way to automatically generate some kind of GUI shell based on the tables that I could then fill in with the logic / functionality I need.
I have coded and run some of the python / tcl examples that I could find so I kind of get that, but it appears to be a bit labor intensive.

Is there an easier way?

Thanks,

Craig
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090720/9a3d6280/attachment-0001.html>

From tvashtar at gmail.com  Mon Jul 20 11:11:34 2009
From: tvashtar at gmail.com (tvashtar)
Date: Mon, 20 Jul 2009 08:11:34 -0700 (PDT)
Subject: Problem when applying Patch from issue1424152 to get https over 
	authenticating proxies working with urllib2 in Python 2.5
Message-ID: <8fe2ad78-0bd4-40d8-909c-1d2784441e3c@s31g2000yqs.googlegroups.com>

Hi,
I'm trying to get https requests working through an authenticating
proxy with urllib2 in Python 2.5, I'm aware that this isn't supported
"out of the box", so applied the patch http://bugs.python.org/file9753/http-tunnel-urllib
linked from http://bugs.python.org/issue1424152 , my baseline test
program is the following:

p = "user:pass at proxy:port"
proxy_handler = urllib2.ProxyHandler({"http": p, "https": p})
urllib2.install_opener( urllib2.build_opener( urllib2.HTTPHandler,
 
urllib2.HTTPSHandler,
 
proxy_handler))

request = urllib2.Request( "https://groups.google.com")
response = urllib2.urlopen(request)

Unfortunately this doesn't work, the call stack being:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 121, in urlopen
    return _opener.open(url, data)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 374, in open
    response = self._open(req, data)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 392, in _open
    '_open', req)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 353, in _call_chain
    result = func(*args)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 1108, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 1075, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error (1, 'error:140770FC:SSL
routines:SSL23_GET_SERVER_HELLO:unknown protocol')>

Does anyone know why I might be hitting this issue?
Any help is greatly appreciated,
thanks


From nikekoo at gmail.com  Mon Jul 20 11:42:15 2009
From: nikekoo at gmail.com (Nike)
Date: Mon, 20 Jul 2009 08:42:15 -0700 (PDT)
Subject: Problem when applying Patch from issue1424152 to get https over 
	authenticating proxies working with urllib2 in Python 2.5
References: <8fe2ad78-0bd4-40d8-909c-1d2784441e3c@s31g2000yqs.googlegroups.com>
Message-ID: <58f2558c-33fe-4ee0-9a0a-2563374be47c@x6g2000prc.googlegroups.com>

On Jul 20, 11:11?pm, tvashtar <tvash... at gmail.com> wrote:
> Hi,
> I'm trying to get https requests working through an authenticating
> proxy with urllib2 in Python 2.5, I'm aware that this isn't supported
> "out of the box", so applied the patchhttp://bugs.python.org/file9753/http-tunnel-urllib
> linked fromhttp://bugs.python.org/issue1424152, my baseline test
> program is the following:
>
> p = "user:pass at proxy:port"
> proxy_handler = urllib2.ProxyHandler({"http": p, "https": p})
> urllib2.install_opener( urllib2.build_opener( urllib2.HTTPHandler,
>
> urllib2.HTTPSHandler,
>
> proxy_handler))
>
> request = urllib2.Request( "https://groups.google.com")
> response = urllib2.urlopen(request)
>
> Unfortunately this doesn't work, the call stack being:
>
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 121, in urlopen
> ? ? return _opener.open(url, data)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 374, in open
> ? ? response = self._open(req, data)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 392, in _open
> ? ? '_open', req)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 353, in _call_chain
> ? ? result = func(*args)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 1108, in https_open
> ? ? return self.do_open(httplib.HTTPSConnection, req)
> ? File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
> \urllib2.py", line 1075, in do_open
> ? ? raise URLError(err)
> urllib2.URLError: <urlopen error (1, 'error:140770FC:SSL
> routines:SSL23_GET_SERVER_HELLO:unknown protocol')>
>
> Does anyone know why I might be hitting this issue?
> Any help is greatly appreciated,
> thanks

hi!
 It's looks like a ssl error . Under the following step to help u :
  1. takes a simple code to confirm your pupose without ssl protocol.
  2. to confirm python version and extended libs work well
  3. to confirm ssl work well.

goog luck!

nikekoo


From hyugaricdeau at gmail.com  Mon Jul 20 11:52:39 2009
From: hyugaricdeau at gmail.com (Hyuga)
Date: Mon, 20 Jul 2009 08:52:39 -0700 (PDT)
Subject: are user defined classes hashable?
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<mailman.3392.1248012803.8015.python-list@python.org> 
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net>
	<mailman.3396.1248018412.8015.python-list@python.org>
Message-ID: <373d6c69-6965-4a88-bdd2-8028ef850bf8@k6g2000yqn.googlegroups.com>

On Jul 19, 11:39?am, Nicolas Dandrimont <Nicolas.Dandrim... at crans.org>
wrote:
> * Alan G Isaac <alan.is... at gmail.com> [2009-07-19 14:46:12 +0000]:
>
> > Again, my question is about the class not its instances,
> > but still, checking as you suggest gives the same answer.
>
> That's what I get for answering before my coffee!

Regardless, Nicolas's example can be applied to the class too:

>>> class Foo(object):
	pass

>>> hash(Foo)
11443104
>>> id(Foo)
11443104

class objects are just objects of type 'type'.


From dtgeadamo at yahoo.com  Mon Jul 20 11:55:35 2009
From: dtgeadamo at yahoo.com (mistersexy)
Date: Mon, 20 Jul 2009 08:55:35 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
Message-ID: <a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>

On Jul 20, 3:03?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> mistersexy wrote:
> > I am trying to create a Windows service in Python using pywin32. I do
> > not want this service to run under a user account. I want this service
> > to be able to run as a LocalService, NetworkService and the like. How
> > do I specify this using the win32 library? Thanks, everyone.
>
> When you "install" the service, using the HandleCommandLine
> option, specify --username= and --password options.
>
> TJG

That's exactly my point. I do not want to have to specify username and
password options. For instance, when creating a Windows Service
in .NET, it is possible to specify that the service should run using
the LocalService or NetworkService account. Doing this, you would not
need to specify username and password options. Is there a way to
achieve this in Python?


From aahz at pythoncraft.com  Mon Jul 20 12:00:33 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 09:00:33 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application Server
	0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
Message-ID: <h424b1$gj1$1@panix3.panix.com>

In article <mailman.3416.1248070578.8015.python-announce-list at python.org>,
tkouts  <python-list at python.org> wrote:
>
>I'm pleased to announce the new version of Porcupine Web Application
>Server, a Python based framework that provides front-end and back-end
>technologies for building modern data-centric Web 2.0 applications.
>
>  [...]
>
>QuiX, the server's integrated JavaScript toolkit, has reached the
>major milestone of supporting all the popular browsers including
>Opera, Safari 4 and IE8.  [...]

Out of curiosity, are there any JavaScript toolkits that generate code
that degrades gracefully when JavaScript is disabled?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From vs at it.uu.se  Mon Jul 20 12:09:42 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Mon, 20 Jul 2009 18:09:42 +0200
Subject: On out-of-date Python Applications
In-Reply-To: <4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>
References: <mailman.3387.1247990649.8015.python-list@python.org>	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>	<4A632C9D.2010303@it.uu.se>	<mailman.3397.1248018457.8015.python-list@python.org>	<e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
	<4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>
Message-ID: <4A6496C6.4040606@it.uu.se>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090720/05384fdc/attachment-0001.html>

From mail at timgolden.me.uk  Mon Jul 20 12:14:31 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Mon, 20 Jul 2009 17:14:31 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
Message-ID: <4A6497E7.7090908@timgolden.me.uk>

mistersexy wrote:
> On Jul 20, 3:03 pm, Tim Golden <m... at timgolden.me.uk> wrote:
>> mistersexy wrote:
>>> I am trying to create a Windows service in Python using pywin32. I do
>>> not want this service to run under a user account. I want this service
>>> to be able to run as a LocalService, NetworkService and the like. How
>>> do I specify this using the win32 library? Thanks, everyone.
>> When you "install" the service, using the HandleCommandLine
>> option, specify --username= and --password options.
>>
>> TJG
> 
> That's exactly my point. I do not want to have to specify username and
> password options. For instance, when creating a Windows Service
> in .NET, it is possible to specify that the service should run using
> the LocalService or NetworkService account. Doing this, you would not
> need to specify username and password options. Is there a way to
> achieve this in Python?

Sorry, I misread: I mentally removed the "not" in your 'I do not want
this service to run under a user account' and reinserted it
further on!

By default, the service will run as LocalSystem: you
only specify a username to override that default. The value
in Username is passed straight through to the CreateService
Win32 API, and the docs for that:

  http://msdn.microsoft.com/en-us/library/ms682450%28VS.85%29.aspx


say:

"""
lpServiceStartName [in, optional]

    The name of the account under which the service should run. If the service type is SERVICE_WIN32_OWN_PROCESS, use an account name in the form DomainName\UserName. The service process will be logged on as this user. If the account belongs to the built-in domain, you can specify .\UserName.

    If this parameter is NULL, CreateService uses the LocalSystem account. If the service type specifies SERVICE_INTERACTIVE_PROCESS, the service must run in the LocalSystem account.

    If this parameter is NT AUTHORITY\LocalService, CreateService uses the LocalService account. If the parameter is NT AUTHORITY\NetworkService, CreateService uses the NetworkService account.

    A shared process can run as any user.

    If the service type is SERVICE_KERNEL_DRIVER or SERVICE_FILE_SYSTEM_DRIVER, the name is the driver object name that the system uses to load the device driver. Specify NULL if the driver is to use a default object name created by the I/O system.

    A service can be configured to use a managed account or a virtual account. If the service is configured to use a managed service account, the name is the managed service account name. If the service is configured to use a virtual account, specify the name as NT SERVICE\ServiceName. For more information about managed service accounts and virtual accounts, see the Service Accounts Step-by-Step Guide.

        Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP/2000:  Managed service accounts and virtual accounts are not supported until Windows 7 and Windows Server 2008 R2.
"""



So, although I haven't tried it, it looks as though you can pass 
"LocalService" or "NetworkService" and so on if you want to
override the default LocalSystem but don't want to specify a
username/password.

TJG


From ebonak at hotmail.com  Mon Jul 20 12:22:47 2009
From: ebonak at hotmail.com (Esmail)
Date: Mon, 20 Jul 2009 12:22:47 -0400
Subject: comments? storing a function in an object
Message-ID: <h425ks$fo7$1@ger.gmane.org>

Hello all,

I am trying to store a function and some associated information in an
object so that I can later have series of functions in a list that I can
evaluate one at a time.

Right now I am only storing the function itself, the number of
arguments it expects and its string representation. I may add other
information such as the acceptable range for the parameters or other
characteristics such as maximum or minimum.

I wonder if anyone could comment on my implementation and offer
suggestions or constructive criticisms?

The 'loading' of the functions is a bit tedious and of course care
has to be taken to make sure the string representation corresponds to
the actual function computed. It would be nice if there was an
automatic way to convert the function to its string representation.

Comments or problems with the approach I have taken?

Thanks,
Esmail

--

#!/usr/bin/env python

#
# store and represent functions
#

import math

class FunctionException(Exception):
     """ custom exception """
     def __init__(self, value):
         self.parameter = value

     def __str__(self):
         return repr(self.parameter)



class Function(object):
     """ class to represent a function """

     def __init__(self, fn, fn_str, num_vars):
         """
         the function, its string representation, and the number of variables
         """
         self.fn = fn
         self.fn_str = fn_str
         self.num_vars = num_vars


     def eval_fn(self, variables):
         """ size of variables should equal num_vars .. else problem """
         if len(variables) == self.num_vars:
             result = self.fn(*variables)
             return result
         else:
             raise FunctionException('invalid number of args provided - '+
                                     'received %d, expected %d'
                                     %(len(variables), self.num_vars))


     def str(self):
         """ return string representation of function """
         return self.fn_str




def funct1(x):
     ''' small test function '''
     return x * x


def funct2(x, y):
     ''' small test function '''
     return x + y


def funct3(x):
     ''' small test function '''
     return 1000 + (x*x + x) * math.cos(x)





def main():
     """ main method """
     print 'in main'

     fn1 = Function(funct1, 'x * x', 1)
     fn2 = Function(funct2, 'x + y', 2)
     fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)

     for i in range(-10, 10):
         try:

             print 'f(', [i],') =',
             print fn3.str(), ' => ',
             print fn3.eval_fn([i])

         except FunctionException, (ex):
             print ex.parameter



if __name__ == '__main__':
     main()



From dtgeadamo at yahoo.com  Mon Jul 20 12:25:44 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Mon, 20 Jul 2009 09:25:44 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
Message-ID: <1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>

On Jul 20, 5:14?pm, Tim Golden <m... at timgolden.me.uk> wrote:
> mistersexy wrote:
> > On Jul 20, 3:03 pm, Tim Golden <m... at timgolden.me.uk> wrote:
> >> mistersexy wrote:
> >>> I am trying to create a Windows service in Python using pywin32. I do
> >>> not want this service to run under a user account. I want this service
> >>> to be able to run as a LocalService, NetworkService and the like. How
> >>> do I specify this using the win32 library? Thanks, everyone.
> >> When you "install" the service, using the HandleCommandLine
> >> option, specify --username= and --password options.
>
> >> TJG
>
> > That's exactly my point. I do not want to have to specify username and
> > password options. For instance, when creating a Windows Service
> > in .NET, it is possible to specify that the service should run using
> > the LocalService or NetworkService account. Doing this, you would not
> > need to specify username and password options. Is there a way to
> > achieve this in Python?
>
> Sorry, I misread: I mentally removed the "not" in your 'I do not want
> this service to run under a user account' and reinserted it
> further on!
>
> By default, the service will run as LocalSystem: you
> only specify a username to override that default. The value
> in Username is passed straight through to the CreateService
> Win32 API, and the docs for that:
>
> ?http://msdn.microsoft.com/en-us/library/ms682450%28VS.85%29.aspx
>
> say:
>
> """
> lpServiceStartName [in, optional]
>
> ? ? The name of the account under which the service should run. If the service type is SERVICE_WIN32_OWN_PROCESS, use an account name in the form DomainName\UserName. The service process will be logged on as this user. If the account belongs to the built-in domain, you can specify .\UserName.
>
> ? ? If this parameter is NULL, CreateService uses the LocalSystem account. If the service type specifies SERVICE_INTERACTIVE_PROCESS, the service must run in the LocalSystem account.
>
> ? ? If this parameter is NT AUTHORITY\LocalService, CreateService uses the LocalService account. If the parameter is NT AUTHORITY\NetworkService, CreateService uses the NetworkService account.
>
> ? ? A shared process can run as any user.
>
> ? ? If the service type is SERVICE_KERNEL_DRIVER or SERVICE_FILE_SYSTEM_DRIVER, the name is the driver object name that the system uses to load the device driver. Specify NULL if the driver is to use a default object name created by the I/O system.
>
> ? ? A service can be configured to use a managed account or a virtual account. If the service is configured to use a managed service account, the name is the managed service account name. If the service is configured to use a virtual account, specify the name as NT SERVICE\ServiceName. For more information about managed service accounts and virtual accounts, see the Service Accounts Step-by-Step Guide.
>
> ? ? ? ? Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP/2000: ?Managed service accounts and virtual accounts are not supported until Windows 7 and Windows Server 2008 R2.
> """
>
> So, although I haven't tried it, it looks as though you can pass
> "LocalService" or "NetworkService" and so on if you want to
> override the default LocalSystem but don't want to specify a
> username/password.
>
> TJG

I'll try this stuff. Thanks a million...I'll let everyone know how it
goes.


From bearophileHUGS at lycos.com  Mon Jul 20 12:26:08 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Mon, 20 Jul 2009 09:26:08 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>

William Dode':
> I just tested it with a litle game, to find the places of horse on
> a board 5x5. The result is :
>
> c 5s
> gcj 7s
> java 7s
> shedskin 8s
> python + psyco 18s
> cython avec malloc *int 18s
> cython 55s avec [] python
> python 303s (5m3s)

Nice timings, can you please show me the Python, Java and C code
versions? I may do more tests.
The purpose of all those "example programs" in ShedSkin is to find
bugs and to find details to speedup.

Bye,
bearophile


From phillip.oldham at gmail.com  Mon Jul 20 12:27:05 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Mon, 20 Jul 2009 17:27:05 +0100
Subject: Help understanding the decisions *behind* python?
Message-ID: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>

My colleagues and I have been working with python for around 6 months
now, and while we love a lot of what python has done for us and what
it enables us to do some of the decisions behind such certain
data-types and their related methods baffle us slightly (when compared
to the decisions made in other, similarly powerful languages).

Specifically the "differences" between lists and tuples have us
confused and have caused many "discussions" in the office. We
understand that lists are mutable and tuples are not, but we're a
little lost as to why the two were kept separate from the start. They
both perform a very similar job as far as we can tell.

Consider the following:

>>> x = [2,1,3]
>>> x.sort()
>>> print x
[1, 2, 3]

Now, if the sort operations were unable to affect the original
structure of the list (as in JavaScript) you'd effectively have a
tuple which you could add/remove from, and the example above would
look more like:

>>> x = [2,1,3]
>>> print x.sort()
[1, 2, 3]
>>> print x
[2,1,3]

This make a lot more sense to us, and follows the convention from
other languages. It would also mean chaining methods to manipulate
lists would be easier:

>>> x = [2,1,3]
>>> print x.sort()[0]
3
>>> print x
[2,1,3]

We often find we need to do manipulations like the above without
changing the order of the original list, and languages like JS allow
this. We can't work out how to do this in python though, other than
duplicating the list, sorting, reversing, then discarding.

We're not looking to start any arguments or religious wars and we're
not asking that python be changed into something its not. We'd simply
like to understand the decision behind the lists and tuple structures.
We feel that in not "getting" the difference between the two types we
may be missing out on using these data structures to their full
potential.


From tycho at tycho.ws  Mon Jul 20 12:43:16 2009
From: tycho at tycho.ws (Tycho Andersen)
Date: Mon, 20 Jul 2009 11:43:16 -0500
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
Message-ID: <49b3a7400907200943s2ed382c7qa0a38aa67db79885@mail.gmail.com>

On Mon, Jul 20, 2009 at 11:27 AM, Phillip B
Oldham<phillip.oldham at gmail.com> wrote:
> <snip>
> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.
>

I have no idea about why the design decisions were made. You might
take a look at the sorted() function:
http://docs.python.org/library/functions.html#sorted

It will do what you want.

\t
--
http://tycho.ws


From http  Mon Jul 20 12:50:56 2009
From: http (Paul Rubin)
Date: 20 Jul 2009 09:50:56 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
Message-ID: <7xljmjguxb.fsf@ruckus.brouhaha.com>

vippstar <vippstar at gmail.com> writes:
> > I wonder whether 2/3 => ValueError is preferable.
> 
> Not all software wants this. It shouldn't be part of the language but
> rather part of your code if you need such a feature. (for instance, to
> distinguish between 2/3 and divisions with 0 dividend).

I don't see how to implement such a thing in my code, if I believe
that the ring of integers doesn't have any concept of division and so
attempts to divide integers should be treated as errors.  Yes of
course the present / operator is useful, but I could do just as well
with the divmod function which I think is more explicit.


From marcusw at cox.net  Mon Jul 20 13:06:39 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 13:06:39 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <7x4ot7rif8.fsf@ruckus.brouhaha.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
Message-ID: <h4286v$8ja$1@adenine.netfront.net>

On 7/20/2009 2:13 AM, Paul Rubin wrote:
> Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:
>> Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing 
>> to do. It's the right thing to do if you're doing integer maths.
> 
> I wonder whether 2/3 => ValueError is preferable.
Not for me :(


From duncan.booth at invalid.invalid  Mon Jul 20 13:08:38 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 20 Jul 2009 17:08:38 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <Xns9C4EB8936A361duncanbooth@127.0.0.1>

Phillip B Oldham <phillip.oldham at gmail.com> wrote:

> This make a lot more sense to us, and follows the convention from
> other languages. It would also mean chaining methods to manipulate
> lists would be easier:
> 
>>>> x = [2,1,3]
>>>> print x.sort()[0]
> 3
>>>> print x
> [2,1,3]

You already have a way to do what you want:

>>> x = [2,1,3]
>>> print sorted(x)[0]
3
>>> print x
[2,1,3]

as a bonus you can use 'sorted' to sort any sequence including generators 
or tuples, but the result will always be a list: if it was a list method 
then you would have to convert the sequence to a list first.

The main reason why you need both lists and tuples is that because a tuple 
of immutable objects is itself immutable you can use it as a dictionary 
key. You can't use a list as a dictionary key because if something were to 
mutate a key the dictionary structure would behave very strangely indeed.
The types 'set' and 'frozenset' both exist for the same reason.


From darcy at druid.net  Mon Jul 20 13:08:56 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Mon, 20 Jul 2009 13:08:56 -0400
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
In-Reply-To: <h424b1$gj1$1@panix3.panix.com>
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
Message-ID: <20090720130856.fdee4c6d.darcy@druid.net>

On 20 Jul 2009 09:00:33 -0700
aahz at pythoncraft.com (Aahz) wrote:
> Out of curiosity, are there any JavaScript toolkits that generate code
> that degrades gracefully when JavaScript is disabled?

I understand what you want but I can't see how a toolkit can do that.
How do you program "graceful?"  It seems pretty application specific.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From marcusw at cox.net  Mon Jul 20 13:11:20 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 13:11:20 -0400
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <mailman.3419.1248082444.8015.python-list@python.org>
References: <mailman.3406.1248034495.8015.python-list@python.org>	<h40adj$bv6$1@adenine.netfront.net>
	<mailman.3419.1248082444.8015.python-list@python.org>
Message-ID: <h428fp$8ja$2@adenine.netfront.net>

On 7/20/2009 5:34 AM, Stef Mientki wrote:
> thanks Marcus,
> 
> Marcus Wanner wrote:
>> On 7/19/2009 4:15 PM, Stef Mientki wrote:
>>> hello,
>>>
>>> I'm using Scintilla as a wxPython widget with great pleasure.
>>> I now have an application where I want to make notes during a 
>>> conversation,
>>> but also want to record the speech during that conversation.
>>> I'm using Scintilla as a wxPython widget for editing and PyAudio for 
>>> the speech recording,
>>> until so far everything works fine.
>>>
>>> Here the problem part:
>>> I need to synchronize the typed text with the sound during playback.
>>> So if I click somewhere in the sound recording,
>>> the line of text, typed that moment should be highlighted.
>>> And vise versa, if the cursor in the text is moved and some special 
>>> key is pressed,
>>> the sound starting 10 or 20seconds earlier should be playbacked.
>>>
>>> I though of adding bookmarks (because these are fixed in the text), 
>>> and keep a list of bookmarks and sound pointers.
>>> This idea should work, but there are only 31 bookmarks.
>>>
>>> Any other suggestions ?
>>>
>>> thanks,
>>> Stef Mientki
>> That sounds like a very specialized type of thing, 
> Well from an application point of view,
> with the current netbooks,
> this looks like a perfect tool for any conversation or meeting.
>> which only the few people with experience with wxPython, PyAudio, and 
>> Scintilla could help you with...
>>
> I was afraid of that too, so I dropped the question in several places,
> and the writer of Scintilla himself came with the perfect answer.
> 
> cheers,Stef
>> But you might try having a dictionary with notes and associated times, 
>> or just give each note a four-digit ID number at the beginning of it 
>> when it's entered and use that in the dictionary (to keep keys 
>> shorter). Or you could just do a little hack and increase the number 
>> of bookmarks allowed (seeing as source is available) :p
>>
>> Marcus
> 
Glad you got a good answer from somebody. Sounds like an interesting 
project. About when would this be headed for a release? Could you post a 
link to a googlecode or sourceforge project or something so I can follow 
and/or help with development?

Marcus


From motoom at xs4all.nl  Mon Jul 20 13:17:19 2009
From: motoom at xs4all.nl (Michiel Overtoom)
Date: Mon, 20 Jul 2009 19:17:19 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
Message-ID: <4A64A69F.2030400@xs4all.nl>

Phillip wrote:

> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.

Yes, but because of their immutability you can use tuples as dictionary 
keys (only if they contain immutable objects).
Lists can't be used as dictionary keys.

Greetings,

-- 
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Valloppillil
http://www.catb.org/~esr/halloween/halloween4.html


From gerard.blais at gmail.com  Mon Jul 20 13:28:09 2009
From: gerard.blais at gmail.com (MCIPERF)
Date: Mon, 20 Jul 2009 10:28:09 -0700 (PDT)
Subject: win32api install problem
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
	<mailman.3424.1248098235.8015.python-list@python.org>
Message-ID: <b1b9ef55-c740-4a9e-ba33-4aa1e88dc5f5@f33g2000vbm.googlegroups.com>

On Jul 20, 9:57?am, Tim Golden <m... at timgolden.me.uk> wrote:
> Gerry wrote:
> > I'm running Python 2.6 under XP.
>
> > I've installed Windows 32 extensions for Python 2.6 version 1.4
> > (pywin32-214.win32-py2.6.exe).
>
> > But If I try to import win32api, I get:
>
> > ? File "C:\python_projects\euler\driveletters.py", line 1, in <module>
> > ? ? import win32api
> > ImportError: DLL load failed: The specified module could not be found.
>
> Used to be you'd get this error if you installed as a
> non-admin user. Don't know if that's still an issue.
> Possibility?
>
> TJG

Not a possibility (afaict) -- I am an administrator, according to the
control panel.


From marcusw at cox.net  Mon Jul 20 13:42:55 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 13:42:55 -0400
Subject: Design question.
In-Reply-To: <68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>
	<mailman.3423.1248095131.8015.python-list@python.org>
	<68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
Message-ID: <h42abb$9nk$1@adenine.netfront.net>

On 7/20/2009 9:42 AM, Lacrima wrote:
> On Jul 20, 4:05 pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
> wrote:
>> Lacrima wrote:
>>> Hello!
>>> I am newbie in python and I have really simple question, but I need
>>> your advice to know how to do best.
>>> I need to store a number of dictionaries in certain place. I've
>>> decided to store them in a separate module.
>>> Like this:
>>> dicts.py
>>> -----------------------
>>> dict1 = {....}
>>> dict2 = {....}
>>> dict3 = {....}
>>> Then, when I need any dictionary, I can access it:
>>> import dicts
>>> dicts.dict1
>>> Is it a good practice? Or should I store them as class attributes or
>>> anything else?
>>> Thanks in advance.
>>> With regards, Max
>>> (sorry if my English isn't very proper)
>> Defining dict as a module attribute ic correct, but try to answer the
>> following question:
>>
>> Is dict1 an attribute/property/declension of the object/entity defined
>> by the module dicts ?
>> If yes, then your design is correct.
>>
>> An correct example:
>> fruits.py
>> ------------
>> apple = {}
>> banana = {}
>>
>> An incorrect one:
>> fruit.py
>> -----------
>> apple={}
>> bicycle={}
>>
>> Basically, the rule is very straightforward, set your dict as a module
>> attribute only if its one of its attribute (very nice paraphrase !)
>> Most of people (including me) tend to have a  module, where they put
>> everything they have no idea about their location. This is a bad habit
>> and result from a uncontrolled/undocumented design. Usually documenting
>> objects in such modules is really painful.
>>
>> Your proposal is fine from a python syntax point of view. I can't tell
>> of your design with names like (dicts.py and dict1,dict2) hoping you do
>> not intend to name them that way.
>>
>> JM
> 
> Hi, Jean-Michel!
> 
> Thanks for your answer.
> I am not going to have names like dicts.py and dict1,dict2. That was
> just example. I wanted to know if it is correct to have dictionaries
> on a module level. Now I know that this is correct. I want to collect
> in one module a number of dictionaries, every of which describes a
> separate web service. And my function in another module will import
> required dictionary, depending on what web service should be used.
> Thanks again for the help.
> 
> With regards,
> Max.
> (sorry if my English isn't very proper)
Yeah, you can put just about anything in a separate module/file, but 
putting unrelated things in the same module is bad...

For example, if you have apple and banana in a module, and had a 
function called slicefruit() to do something to those variables in there 
with them, then that would be good. But if you put bicycle and car and 
adjustbrakes() in the module with the fruits, or mixed the two groups in 
several modules, that would be bad.

Marcus


From bieffe62 at gmail.com  Mon Jul 20 13:44:16 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Mon, 20 Jul 2009 10:44:16 -0700 (PDT)
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
Message-ID: <3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>

On Jul 20, 6:22?pm, Esmail <ebo... at hotmail.com> wrote:
> Hello all,
>
> I am trying to store a function and some associated information in an
> object so that I can later have series of functions in a list that I can
> evaluate one at a time.
>
> Right now I am only storing the function itself, the number of
> arguments it expects and its string representation. I may add other
> information such as the acceptable range for the parameters or other
> characteristics such as maximum or minimum.
>
> I wonder if anyone could comment on my implementation and offer
> suggestions or constructive criticisms?
>
> The 'loading' of the functions is a bit tedious and of course care
> has to be taken to make sure the string representation corresponds to
> the actual function computed. It would be nice if there was an
> automatic way to convert the function to its string representation.
>
> Comments or problems with the approach I have taken?
>
> Thanks,
> Esmail
>
> --
>
> #!/usr/bin/env python
>
> #
> # store and represent functions
> #
>
> import math
>
> class FunctionException(Exception):
> ? ? ?""" custom exception """
> ? ? ?def __init__(self, value):
> ? ? ? ? ?self.parameter = value
>
> ? ? ?def __str__(self):
> ? ? ? ? ?return repr(self.parameter)
>
> class Function(object):
> ? ? ?""" class to represent a function """
>
> ? ? ?def __init__(self, fn, fn_str, num_vars):
> ? ? ? ? ?"""
> ? ? ? ? ?the function, its string representation, and the number of variables
> ? ? ? ? ?"""
> ? ? ? ? ?self.fn = fn
> ? ? ? ? ?self.fn_str = fn_str
> ? ? ? ? ?self.num_vars = num_vars
>
> ? ? ?def eval_fn(self, variables):
> ? ? ? ? ?""" size of variables should equal num_vars .. else problem """
> ? ? ? ? ?if len(variables) == self.num_vars:
> ? ? ? ? ? ? ?result = self.fn(*variables)
> ? ? ? ? ? ? ?return result
> ? ? ? ? ?else:
> ? ? ? ? ? ? ?raise FunctionException('invalid number of args provided - '+
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?'received %d, expected %d'
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?%(len(variables), self.num_vars))
>
> ? ? ?def str(self):
> ? ? ? ? ?""" return string representation of function """
> ? ? ? ? ?return self.fn_str
>
> def funct1(x):
> ? ? ?''' small test function '''
> ? ? ?return x * x
>
> def funct2(x, y):
> ? ? ?''' small test function '''
> ? ? ?return x + y
>
> def funct3(x):
> ? ? ?''' small test function '''
> ? ? ?return 1000 + (x*x + x) * math.cos(x)
>
> def main():
> ? ? ?""" main method """
> ? ? ?print 'in main'
>
> ? ? ?fn1 = Function(funct1, 'x * x', 1)
> ? ? ?fn2 = Function(funct2, 'x + y', 2)
> ? ? ?fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)
>
> ? ? ?for i in range(-10, 10):
> ? ? ? ? ?try:
>
> ? ? ? ? ? ? ?print 'f(', [i],') =',
> ? ? ? ? ? ? ?print fn3.str(), ' => ',
> ? ? ? ? ? ? ?print fn3.eval_fn([i])
>
> ? ? ? ? ?except FunctionException, (ex):
> ? ? ? ? ? ? ?print ex.parameter
>
> if __name__ == '__main__':
> ? ? ?main()


I can offer some small suggestions: it is up to you to evaluate if
they make sense for your app:

1. use __doc__ function standard attribute for function description
(your fn_str); this meanst that
   you do not need fm_str in the constructor and you have to do e.g. :

def funct2(x, y):
      ''' x + y '''
      return x + y

then funct2.__doc__  becomes the string you want to associate to the
function

2. Use __call__ instead of eval_fn : this way, the instance of your
Function became a 'callable' and can be used
   everywhere a function is needed. You can do:

   f = Function(...)
   f( some_args )

3. If you call a python function with wrong number of arguments, it
already raises a TypeError exception which contains
   - with different wording - the same information of your
FunctionException : consider removing the check and using the
   python error instead


HTH

Ciao
------
FB




From drobinow at gmail.com  Mon Jul 20 13:46:26 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 20 Jul 2009 13:46:26 -0400
Subject: On out-of-date Python Applications
In-Reply-To: <4A6496C6.4040606@it.uu.se>
References: <mailman.3387.1247990649.8015.python-list@python.org>
	<63767354-1f6a-44fe-8c57-05873503a90e@b25g2000prb.googlegroups.com>
	<4A632C9D.2010303@it.uu.se>
	<mailman.3397.1248018457.8015.python-list@python.org>
	<e4f0b2d4-b71a-4549-ad36-452f2b12edeb@p36g2000prn.googlegroups.com>
	<4eb0089f0907200446p23d452fes1c5727676e92bf81@mail.gmail.com>
	<4A6496C6.4040606@it.uu.se>
Message-ID: <4eb0089f0907201046x4bdc3b10t3ad56a888526eff2@mail.gmail.com>

On Mon, Jul 20, 2009 at 12:09 PM, Virgil Stokes<vs at it.uu.se> wrote:
> David Robinow wrote:
>
> On Mon, Jul 20, 2009 at 7:24 AM, John Machin<sjmachin at lexicon.net> wrote:
> ...
>
>
> The next step would be to try to compile ODE 0.7 or 0.8 with VS9 --
> however this would require "project files" for ODE for VS9, and there
> aren't any on the ODE website; it has only those for VS3 and VS5.
>
>
>
>  The ODE site is a mess.
> Go to http://www.ode.org/svn.html  and click on:   Instructions for
> accessing the repository
>  Scroll down to the section "Building with Premake"
>  (Note that there is no directory "ode/build" -- you want the "build"
> directory, which contains premake4.exe)
> I used "premake4 --with-demos --with-tests vs2008"
> I have successfully compiled ode-0.11.1 using these instructions. I
> have not yet run the tests or demos or tried to compile PyODE.
>
>
> Thanks for this information David.
> Now that you have successfully compiled ode-0.11.1, how can one finish this
> process --- compile PyODE?
>
> --V
>
Edit setup.py       Windows specific settings:
 ODE_BASE to location of your ode distribution
 create releaselib directory under lib and copy the .lib file that you built in
Visual Studio.  This will be:
   ReleaseSingleLib\ode_single.lib  or
   ReleaseDoubleLib\ode_double.lib  or one of the Debug versions
 Change the name to ode.lib.
 i.e. in CMD-speak:  %ODE_BASE%\lib\releaselib\ode.lib

I was then able to build PyODE-1.2.0

However, all the examples died with:
  ODE Message 2: mass must be > 0 <..\..\ode\src\mass.cpp:49)

I don't have time right now to debug this. Maybe somebody else can take it a
bit further.


From tvashtar at gmail.com  Mon Jul 20 13:58:53 2009
From: tvashtar at gmail.com (tvashtar)
Date: Mon, 20 Jul 2009 10:58:53 -0700 (PDT)
Subject: Problem when applying Patch from issue1424152 to get https over 
	authenticating proxies working with urllib2 in Python 2.5
References: <8fe2ad78-0bd4-40d8-909c-1d2784441e3c@s31g2000yqs.googlegroups.com>
	<58f2558c-33fe-4ee0-9a0a-2563374be47c@x6g2000prc.googlegroups.com>
Message-ID: <446a3c42-6d86-4003-85be-3e5d8a23b268@c14g2000yqm.googlegroups.com>

On Jul 20, 4:42?pm, Nike <nike... at gmail.com> wrote:
> hi!
> ?It's looks like a ssl error . Under the following step to help u :
> ? 1. takes a simple code to confirm your pupose without ssl protocol.
> ? 2. to confirm python version and extended libs work well
> ? 3. to confirm ssl work well.
>
> goog luck!
>
> nikekoo

I've reduced my code to the following:

import urllib2

p = "https://user:pass at myproxy:port"
proxy_handler = urllib2.ProxyHandler({"https": p})
urllib2.install_opener(urllib2.build_opener(proxy_handler))
request = urllib2.Request( "https://groups.google.com")
response = urllib2.urlopen(request)

and it is now failing with:

Traceback (most recent call last):
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\test.py", line 12, in <module>
    response = urllib2.urlopen(request)
  File "C:\Python25\lib\urllib2.py", line 121, in urlopen
    return _opener.open(url, data)
  File "C:\Python25\lib\urllib2.py", line 379, in open
    response = self._open(req, data)
  File "C:\Python25\lib\urllib2.py", line 397, in _open
    '_open', req)
  File "C:\Python25\lib\urllib2.py", line 358, in _call_chain
    result = func(*args)
  File "C:\Python25\lib\urllib2.py", line 1115, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "C:\Python25\lib\urllib2.py", line 1082, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error Tunnel connection failed: 407 Proxy
Authentication Required>

I thought the proxy_handler should take care of the authentication?

Thanks for your help


From kiorky at cryptelium.net  Mon Jul 20 14:19:43 2009
From: kiorky at cryptelium.net (kiorky)
Date: Mon, 20 Jul 2009 20:19:43 +0200
Subject: Compilation problem with Python < 2.6 and db >= 4.7
Message-ID: <4A64B53F.8060502@cryptelium.net>

Is there a way to make the bsddb module compile against db>=4.7 for python < 2.6
(2.4.6, 2.5.4)? A patch ? A tip ?

For the moment, i have a known failure as:
gcc -pthread -fno-strict-aliasing -DNDEBUG
-I/usr/home/kiorky/minitage/dependencies/readline-5.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/bzip2-1.0/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/zlib-1.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/db-4.7/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/expat-2.0/parts/part/include  -I.
-IInclude -I./Include
-I/usr/home/kiorky/minitage/dependencies/readline-5.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/bzip2-1.0/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/zlib-1.2/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/db-4.7/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/openssl-0.9/parts/part/include
-I/usr/home/kiorky/minitage/dependencies/expat-2.0/parts/part/include -fPIC
-DPy_BUILD_CORE
-I/usr/home/kiorky/minitage/dependencies/db-4.7/parts/part/include -c
./Modules/_bsddb.c -o Modules/_bsddb.o
./Modules/_bsddb.c: In function 'DBEnv_getattr':
./Modules/_bsddb.c:5337: error: 'DB_ENV' has no member named 'db_home'
./Modules/_bsddb.c:5340: error: 'DB_ENV' has no member named 'db_home'
./Modules/_bsddb.c: In function 'init_bsddb':
./Modules/_bsddb.c:5962: error: 'DB_LOG_AUTOREMOVE' undeclared (first use in
this function)
./Modules/_bsddb.c:5962: error: (Each undeclared identifier is reported only once
./Modules/_bsddb.c:5962: error: for each function it appears in.)
./Modules/_bsddb.c:5963: error: 'DB_DIRECT_LOG' undeclared (first use in this
function)
./Modules/_bsddb.c:5971: error: 'DB_LOG_INMEMORY' undeclared (first use in this
function)
*** Error code 1


I looked for the one inside python >= 2.6 and it seems to have changed a lot so
backporting it seems difficult and maybe break the old API.

I didn't find something on it.

-- 
--
Cordialement,
KiOrKY
GPG Key FingerPrint: 0x1A1194B7681112AF



From anthony.tolle at gmail.com  Mon Jul 20 14:22:52 2009
From: anthony.tolle at gmail.com (Anthony Tolle)
Date: Mon, 20 Jul 2009 11:22:52 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <df4aeb36-6a4d-49a6-82f1-6ab54862afae@18g2000yqa.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> ...
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
> ...

There's no hard-set rules, but tuples are typically used to hold
collections of heterogeneous data, e.g. (10, "spam", 3.21).  As has
been mentioned, such a tuple can be used as a dictionary key, whereas
a list cannot be used as a dictionary key, because it is mutable.

Lists, on the other hand, typically hold collections of homogeneous
data, e.g. [1, 2, 5] or ["spam", "eggs", "sausage"].

Of course, you'll also see plenty of examples of tuples containing
homogeneous data and lists containing heterogeneous data :)


From lenz at joinville.udesc.br  Mon Jul 20 14:26:50 2009
From: lenz at joinville.udesc.br (Eduardo Lenz)
Date: Mon, 20 Jul 2009 11:26:50 -0700
Subject: ANN: psyco V2
In-Reply-To: <4A5FE672.3000401@stackless.com>
References: <4A5FE672.3000401@stackless.com>
Message-ID: <200907201126.51878.lenz@joinville.udesc.br>

Em Qui 16 Jul 2009, ??s 19:48:18, Christian Tismer escreveu:
> Announcing Psyco V2 source release
> ----------------------------------
>
> This is the long awaited announcement of Psyco V2.
>
> Psyco V2 is a continuation of the well-known psyco project,
> which was called finished and was dis-continued by its author
> Armin Rigo in 2005, in favor of the PyPy project.
>
> This is a new project, using Psyco's code base with permission
> of Armin. Questions and complaints should go to me
> (tismer at stackless.com) or the mailing list
> (psyco-devel at lists.sourceforge.net);
> Armin is explicitly not in charge of (t)his project any longer!
>
> As one of the founders and an active member of the PyPy
> project, I was very happy to be invited to work on Psyco
> V2, by FATTOC, LLC. Psyco V2 tries to extend on the original Psyco
> approach "an extension module that just makes Python faster".
>
> Psyco is a just-in-time compiler that accelerates arbitrary
> Python code by specialization. We believe that Psyco's approach
> can be carried out much further than it was tried so far, when
> it's first version was abandoned.
>
> This first V2 release is source-only. There is no web-site, yet,
> and there are no binaries for download. These will be available
> in a few days on http://www.psyco.org .
>
> For the time being, please stick with subversion access,
> building the extension module from source code. The repository
> is here:
>
>      http://codespeak.net/svn/psyco/v2/dist
>
> Check-out the repository, and run the setup.py script,
> given that you have access to a C compiler.
>
> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
> is well being considered.
>
> The current improvements are, shortly:
>
>    - Support for Python 2.4, 2.5 and 2.6
>    - a lot of new builtins
>    - generators, fast and fully supported.
>
> More information is coming soon on http://www.psyco.org .
>
> This is the beginning of a series of new Psyco versions.
> Many more improvements are prepared and about to be published,
> soon, starting with the current version 2.0.0 .
>
> Stay tuned, this is just the beginning of psyco's re-birth!
>
> For questions about Psyco V2, please join the mailing list
>
>      psyco-devel at lists.sourceforge.net
>
> or contact me on IRC:
>
>      #psyco on irc.freenode.net .
>
> Psyco V2 is fundamentally supported by FATTOC, LLC.
> See http://www.fattoc.com .
>
> Without their continuous support, this work would not have
> been possible at all. I wish to express my deepest thanks
> to FATTOC, for allowing me to continue on Psyco with all the
> energy that this ambitious project needs, and will need.
>
> Further special thanks are going to
> Armin Rigo, John Benediktsson, David Salomon, Miki Tebeka,
> Raymond Hettinger, Fabrizio Milo, Michael Foord,
> Dinu Gherman, Stephan Diehl, Laura Creighton and Andrea Tismer,
> for all the support and discussions.
>
> Looking forward to a great future of Psyco!
>
> July 17, 2009
I know its not the proper list but....

gcc -pthread -fno-strict-aliasing -fwrapv -Wall -Wstrict-prototypes -DNDEBUG -
g -O3 -fPIC -Ic/i386 -Ic -I/usr/include/python2.6 -c c/mergepoints.c -o 
build/temp.linux-i686-2.6/c/mergepoints.o
c/mergepoints.c:250: error: ???RAISE_VARARGS??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???JUMP_IF_FALSE??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???JUMP_IF_TRUE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???DUP_TOPX??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???IMPORT_STAR??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???SLICE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???STORE_SLICE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???DELETE_SLICE??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???PRINT_EXPR??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???PRINT_ITEM??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???PRINT_ITEM_TO??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???PRINT_NEWLINE??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???PRINT_NEWLINE_TO??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???BUILD_CLASS??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???IMPORT_NAME??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???IMPORT_FROM??? undeclared here (not in a function)
c/mergepoints.c:250: error: ???MAKE_FUNCTION??? undeclared here (not in a 
function)
c/mergepoints.c:250: error: ???BUILD_SLICE??? undeclared here (not in a function)
error: command 'gcc' failed with exit status 1

any clue ?

[]'s
Eduardo

 Tel: +55 47 4009-7971 - Fax: +55 47 4009-7940
 E-mail: lenz at Joinville.udesc.br          
 ---------------------------------------------

-- 
Esta mensagem foi verificada pelo sistema de antiv?rus e
 acredita-se estar livre de perigo.



From skip at pobox.com  Mon Jul 20 14:26:56 2009
From: skip at pobox.com (skip at pobox.com)
Date: Mon, 20 Jul 2009 13:26:56 -0500
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <4a645b81$0$12974$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <19044.46832.524925.930667@montanaro.dyndns.org>


    William> c 5s
    William> gcj 7s
    William> java 7s
    William> shedskin 8s
    William> python + psyco 18s
    William> cython avec malloc *int 18s
    William> cython 55s avec [] python
    William> python 303s (5m3s)

I read just enough French to know that "avec" means "with", but I don't
understand the difference between "avec malloc *int" and "avec []".  Can you
explain please?

Thx,

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    That's more than a dress. That's an Audrey Hepburn movie. -- Jerry Maguire


From vippstar at gmail.com  Mon Jul 20 14:31:08 2009
From: vippstar at gmail.com (vippstar)
Date: Mon, 20 Jul 2009 11:31:08 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com> 
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com> 
	<7xljmjguxb.fsf@ruckus.brouhaha.com>
Message-ID: <7a04b07d-2dea-455f-bafd-33461ce25a1a@q11g2000yqi.googlegroups.com>

On Jul 20, 7:50?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> vippstar <vipps... at gmail.com> writes:
> > > I wonder whether 2/3 => ValueError is preferable.
>
> > Not all software wants this. It shouldn't be part of the language but
> > rather part of your code if you need such a feature. (for instance, to
> > distinguish between 2/3 and divisions with 0 dividend).
>
> I don't see how to implement such a thing in my code,
Write a function:

  (if (< x y)
      ValueError
      (/ x y))

This will return 0 only if the dividend = 0, not in integer division x/
y with y > x, which will return ValueError. Of course, ValueError must
not be an integer, because that could be the result of an integer
division. If it's not possible to return multiple types, then the
function can make use of some error handling mechanism.

> if I believe that the ring of integers doesn't have any concept
> of division and so attempts to divide integers should be treated
> as errors.

Wouldn't that mean 3/2 would also evaluate to ValueError? But 3/2 = 1
in integer division, not 0, like 2/3. Regardless, it's a specialized
requirement, and thus should either be implemented by the programmer
or the language could provide it if it's specialized, (for instance, I
wouldn't require a language to provide text manipulation features, but
I expect them from perl because it's not a general all purpose
language [the name designates that, however it can be used as one -
like lisp])

> course the present / operator is useful, but I could do just as well
> with the divmod function which I think is more explicit.
What? Python? Aww.


From bearophileHUGS at lycos.com  Mon Jul 20 14:51:18 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Mon, 20 Jul 2009 11:51:18 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<mailman.3437.1248114427.8015.python-list@python.org>
Message-ID: <04f03d96-46b7-4761-8498-9149f19ecba6@k6g2000yqn.googlegroups.com>

Skip Montanaro:
> I read just enough French to know that "avec" means "with", but I don't
> understand the difference between "avec malloc *int" and "avec []". ?Can you
> explain please?

Maybe it's the time difference between using a Python list from Cython
and using a C "array" allocated with a malloc from Cython.

Bye,
bearophile


From mark.dufour at gmail.com  Mon Jul 20 15:20:55 2009
From: mark.dufour at gmail.com (srepmub)
Date: Mon, 20 Jul 2009 12:20:55 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
Message-ID: <e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>


> Nice timings, can you please show me the Python, Java and C code
> versions? I may do more tests.

also, which shedskin options did you use? did you use -bw, to disable
bounds and wrap-around checking? this can make quite a difference for
code that does a lot of indexing. if the code uses random numbers,
then -r can also make a big difference, to use C rand(), instead of
Python compatible random numbers.

and which C++ compiler flags did you use? the default -O2, or
something like -O3 -fomit-frame-pointer -msse2..?


thanks,
mark.


From phillip.oldham at gmail.com  Mon Jul 20 15:26:07 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Mon, 20 Jul 2009 12:26:07 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
Message-ID: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>

On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> The main reason why you need both lists and tuples is that because a tuple
> of immutable objects is itself immutable you can use it as a dictionary
> key.

Really? That sounds interesting, although I can't think of any real-
world cases where you'd use something like that.


From duncan.booth at invalid.invalid  Mon Jul 20 15:54:02 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 20 Jul 2009 19:54:02 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <Xns9C4ED49939240duncanbooth@127.0.0.1>

Phillip B Oldham <phillip.oldham at gmail.com> wrote:

> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>> The main reason why you need both lists and tuples is that because a
>> tuple of immutable objects is itself immutable you can use it as a
>> dictionary key.
> 
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.
> 

How about a multi-dimensional sparse array?

>>> d = {}
>>> d[1,2] = 'a'
>>> d[5,7] = 'b'



From marcusw at cox.net  Mon Jul 20 16:12:45 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Mon, 20 Jul 2009 16:12:45 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <h42j49$2m2$1@adenine.netfront.net>

On 7/20/2009 3:26 PM, Phillip B Oldham wrote:
> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>> The main reason why you need both lists and tuples is that because a tuple
>> of immutable objects is itself immutable you can use it as a dictionary
>> key.
> 
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.
Actually, that would be very useful in the program from "any suggestions 
to synchronize typed text and speech ?"...i.e. have a dictionary key of 
(hour, minute, second).

Marcus


From jcd at sdf.lonestar.org  Mon Jul 20 16:15:16 2009
From: jcd at sdf.lonestar.org (J. Cliff Dyer)
Date: Mon, 20 Jul 2009 16:15:16 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <1248120917.5967.5.camel@aalcdl07>

On Mon, 2009-07-20 at 12:26 -0700, Phillip B Oldham wrote:
> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> > The main reason why you need both lists and tuples is that because a tuple
> > of immutable objects is itself immutable you can use it as a dictionary
> > key.
> 
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.

Well, if you wanted to index a dictionary by coordinates, you might do
something like this:


fleet = {}
fleet[9,4] = 'destroyer'
fleet[8,4] = 'destroyer'
fleet[3,5] = 'aircraftcarrier'
fleet[4,5] = 'aircraftcarrier'
fleet[5,5] = 'aircraftcarrier'
fleet[6,5] = 'aircraftcarrier'
fleet[8,0] = 'battleship'
fleet[8,1] = 'battleship'
fleet[8,2] = 'battleship'


def checkattack(x, y, fleet):
    if x,y in fleet:
        return "You hit my %s' % fleet[x,y]

Maybe not the best implementation of Battleship, but you get the idea.





From mrstevegross at gmail.com  Mon Jul 20 16:38:57 2009
From: mrstevegross at gmail.com (mrstevegross)
Date: Mon, 20 Jul 2009 13:38:57 -0700 (PDT)
Subject: How to import pydoc and then use it?
Message-ID: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>

I know how to use pydoc from the command line. However, because of
complicated environmental setup, it would be preferable to run it
within a python script as a native API call. That is, my python runner
looks a bit like this:

  import pydoc
  pydoc.generate_html_docs_for(someFile)

However, it's not clear to me from the pydoc documentation which
function calls I need to use to make this behavior work. Any ideas?

Thanks,
--Steve


From nytrokiss at gmail.com  Mon Jul 20 17:01:13 2009
From: nytrokiss at gmail.com (James Matthews)
Date: Tue, 21 Jul 2009 00:01:13 +0300
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
In-Reply-To: <e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
Message-ID: <8a6b8e350907201401k383b0982ma7aeaaf8bf7d7f8a@mail.gmail.com>

I like this, I am going to run this as a test. I also want to see the source
code on how they compile the dynamic variables.

On Mon, Jul 20, 2009 at 10:20 PM, srepmub <mark.dufour at gmail.com> wrote:

>
> > Nice timings, can you please show me the Python, Java and C code
> > versions? I may do more tests.
>
> also, which shedskin options did you use? did you use -bw, to disable
> bounds and wrap-around checking? this can make quite a difference for
> code that does a lot of indexing. if the code uses random numbers,
> then -r can also make a big difference, to use C rand(), instead of
> Python compatible random numbers.
>
> and which C++ compiler flags did you use? the default -O2, or
> something like -O3 -fomit-frame-pointer -msse2..?
>
>
> thanks,
> mark.
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
http://www.jewelerslounge.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/24cdf130/attachment-0001.html>

From egon.frerich at nord-com.net  Mon Jul 20 17:07:38 2009
From: egon.frerich at nord-com.net (Egon Frerich)
Date: Mon, 20 Jul 2009 23:07:38 +0200
Subject: locale doesn' format
Message-ID: <4A64DC9A.3060606@nord-com.net>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I want to format values to the german form eg. 1.034,56 but
locale.format() doesn't work for me.

Here is a little test program:

import decimal, locale

print locale.getdefaultlocale()
print locale.localeconv()
locale.setlocale(locale.LC_ALL, ('de_DE', 'UTF-8'))
print locale.localeconv()
k = decimal.Decimal('1034.56')
#k = 1034.56
print 'k', k, type(k)
k1 = locale.format_string('%12s',k,True)
print 'k1', k1, type(k1)
k1a = locale.format('%12s',k,True,True)
print 'k1a', k1a, type(k1a)
k2 = unicode(k1)
print 'k2',k2,type(k2)
print k1.find(',')
print k1a.find(',')
print k2.find(',')
ab = locale.localeconv()['decimal_point']
print 'ab', ab
print locale.localeconv()['decimal_point'].find(',')
print locale.localeconv()['mon_decimal_point'].find(',')
ac = locale.localeconv()['mon_decimal_point']
print 'ac', ac, len(ac)
print locale.localeconv()

k1, k1a, k2 are printed as 1034.56

Egon

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFKZNyaZRiDo9Iq4qIRAuqhAKCW3x7iDbrxUDp3M/qHabwbw92osQCgi6N2
mmgb54LACmrd/Wi4BRi2iZo=
=psal
-----END PGP SIGNATURE-----


From piet at cs.uu.nl  Mon Jul 20 17:23:25 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 20 Jul 2009 23:23:25 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
Message-ID: <m2fxcrnj5e.fsf@cs.uu.nl>

>>>>> Duncan Booth <duncan.booth at invalid.invalid> (DB) wrote:

>DB> Phillip B Oldham <phillip.oldham at gmail.com> wrote:
>>> This make a lot more sense to us, and follows the convention from
>>> other languages. It would also mean chaining methods to manipulate
>>> lists would be easier:
>>> 
>>>>>> x = [2,1,3]
>>>>>> print x.sort()[0]
>>> 3
>>>>>> print x
>>> [2,1,3]

>DB> You already have a way to do what you want:

>>>>> x = [2,1,3]
>>>>> print sorted(x)[0]
>DB> 3

What kind of Python produces that?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From clp2 at rebertia.com  Mon Jul 20 17:30:16 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Mon, 20 Jul 2009 14:30:16 -0700
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <m2fxcrnj5e.fsf@cs.uu.nl>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
Message-ID: <50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>

On Mon, Jul 20, 2009 at 2:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Duncan Booth <duncan.booth at invalid.invalid> (DB) wrote:
>
>>DB> Phillip B Oldham <phillip.oldham at gmail.com> wrote:
>>>> This make a lot more sense to us, and follows the convention from
>>>> other languages. It would also mean chaining methods to manipulate
>>>> lists would be easier:
>>>>
>>>>>>> x = [2,1,3]
>>>>>>> print x.sort()[0]
>>>> 3
>>>>>>> print x
>>>> [2,1,3]
>
>>DB> You already have a way to do what you want:
>
>>>>>> x = [2,1,3]
>>>>>> print sorted(x)[0]
>>DB> 3
>
> What kind of Python produces that?

Assuming you're referring to the latter example, it was added in version 2.4
If you meant the former example, I think that's purely pseudo-Python.

Cheers,
Chris
-- 
http://blog.rebertia.com


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 17:38:22 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 18:38:22 -0300
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
Message-ID: <op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 20 Jul 2009 14:44:16 -0300, Francesco Bochicchio  
<bieffe62 at gmail.com> escribi?:

> On Jul 20, 6:22?pm, Esmail <ebo... at hotmail.com> wrote:
>> Hello all,
>>
>> I am trying to store a function and some associated information in an
>> object so that I can later have series of functions in a list that I can
>> evaluate one at a time.
>>
>> Right now I am only storing the function itself, the number of
>> arguments it expects and its string representation. I may add other
>> information such as the acceptable range for the parameters or other
>> characteristics such as maximum or minimum.
>>
>> I wonder if anyone could comment on my implementation and offer
>> suggestions or constructive criticisms?
>>
>> The 'loading' of the functions is a bit tedious and of course care
>> has to be taken to make sure the string representation corresponds to
>> the actual function computed. It would be nice if there was an
>> automatic way to convert the function to its string representation.
>>
>> Comments or problems with the approach I have taken?
>>
>> Thanks,
>> Esmail
>>
>> --
>>
>> #!/usr/bin/env python
>>
>> #
>> # store and represent functions
>> #
>>
>> import math
>>
>> class FunctionException(Exception):
>> ? ? ?""" custom exception """
>> ? ? ?def __init__(self, value):
>> ? ? ? ? ?self.parameter = value
>>
>> ? ? ?def __str__(self):
>> ? ? ? ? ?return repr(self.parameter)
>>
>> class Function(object):
>> ? ? ?""" class to represent a function """
>>
>> ? ? ?def __init__(self, fn, fn_str, num_vars):
>> ? ? ? ? ?"""
>> ? ? ? ? ?the function, its string representation, and the number of  
>> variables
>> ? ? ? ? ?"""
>> ? ? ? ? ?self.fn = fn
>> ? ? ? ? ?self.fn_str = fn_str
>> ? ? ? ? ?self.num_vars = num_vars
>>
>> ? ? ?def eval_fn(self, variables):
>> ? ? ? ? ?""" size of variables should equal num_vars .. else problem """
>> ? ? ? ? ?if len(variables) == self.num_vars:
>> ? ? ? ? ? ? ?result = self.fn(*variables)
>> ? ? ? ? ? ? ?return result
>> ? ? ? ? ?else:
>> ? ? ? ? ? ? ?raise FunctionException('invalid number of args provided -  
>> '+
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?'received %d, expected %d'
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?%(len(variables), self.num_vars))
>>
>> ? ? ?def str(self):
>> ? ? ? ? ?""" return string representation of function """
>> ? ? ? ? ?return self.fn_str
>>
>> def funct1(x):
>> ? ? ?''' small test function '''
>> ? ? ?return x * x
>>
>> def funct2(x, y):
>> ? ? ?''' small test function '''
>> ? ? ?return x + y
>>
>> def funct3(x):
>> ? ? ?''' small test function '''
>> ? ? ?return 1000 + (x*x + x) * math.cos(x)
>>
>> def main():
>> ? ? ?""" main method """
>> ? ? ?print 'in main'
>>
>> ? ? ?fn1 = Function(funct1, 'x * x', 1)
>> ? ? ?fn2 = Function(funct2, 'x + y', 2)
>> ? ? ?fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)
>>
>> ? ? ?for i in range(-10, 10):
>> ? ? ? ? ?try:
>>
>> ? ? ? ? ? ? ?print 'f(', [i],') =',
>> ? ? ? ? ? ? ?print fn3.str(), ' => ',
>> ? ? ? ? ? ? ?print fn3.eval_fn([i])
>>
>> ? ? ? ? ?except FunctionException, (ex):
>> ? ? ? ? ? ? ?print ex.parameter
>>
>> if __name__ == '__main__':
>> ? ? ?main()
>
>
> I can offer some small suggestions: it is up to you to evaluate if
> they make sense for your app:
>
> 1. use __doc__ function standard attribute for function description
> (your fn_str); this meanst that
>    you do not need fm_str in the constructor and you have to do e.g. :
>
> def funct2(x, y):
>       ''' x + y '''
>       return x + y
>
> then funct2.__doc__  becomes the string you want to associate to the
> function
>
> 2. Use __call__ instead of eval_fn : this way, the instance of your
> Function became a 'callable' and can be used
>    everywhere a function is needed. You can do:
>
>    f = Function(...)
>    f( some_args )
>
> 3. If you call a python function with wrong number of arguments, it
> already raises a TypeError exception which contains
>    - with different wording - the same information of your
> FunctionException : consider removing the check and using the
>    python error instead

If you follow the above suggestions, you'll see that your Function class  
becomes almost useless: a normal function already IS an object, so you  
don't have to wrap it inside ANOTHER object unless you need very special  
features.

-- 
Gabriel Genellina



From aahz at pythoncraft.com  Mon Jul 20 17:40:05 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 14:40:05 -0700
Subject: any suggestions to synchronize typed text and speech ?
References: <mailman.3406.1248034495.8015.python-list@python.org>
	<h40adj$bv6$1@adenine.netfront.net>
	<mailman.3419.1248082444.8015.python-list@python.org>
Message-ID: <h42o7l$bsp$1@panix3.panix.com>

In article <mailman.3419.1248082444.8015.python-list at python.org>,
Stef Mientki  <stef.mientki at gmail.com> wrote:
>
>I was afraid of that too, so I dropped the question in several places,
>and the writer of Scintilla himself came with the perfect answer.

...which was?...
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From gagsl-py2 at yahoo.com.ar  Mon Jul 20 17:40:14 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 20 Jul 2009 18:40:14 -0300
Subject: Auto-generate GUI from a database table structure
References: <55660F9659966544BBA3AE14CE5D278D01243B8E04@exgtmb08.nam.nsroot.net>
Message-ID: <op.uxdyhcvlx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 20 Jul 2009 12:09:47 -0300, Boyd, Craig1  <craig1.boyd at citi.com>  
escribi?:

> I am trying to write a couple screens to update three or four database  
> tables on Oracle 10g and I was wondering if there was a way to  
> automatically generate some kind of GUI shell based on the tables that I  
> could then fill in with the logic / functionality I need.

I've never actually used it, but the DABO project seems to provide what  
you want: http://dabodev.com/

-- 
Gabriel Genellina



From marduk at letterboxes.org  Mon Jul 20 17:40:19 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Mon, 20 Jul 2009 17:40:19 -0400
Subject: How to import pydoc and then use it?
In-Reply-To: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>
References: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>
Message-ID: <1248126024.9281.3.camel@centar>

On Mon, 2009-07-20 at 13:38 -0700, mrstevegross wrote:
> I know how to use pydoc from the command line. However, because of
> complicated environmental setup, it would be preferable to run it
> within a python script as a native API call. That is, my python runner
> looks a bit like this:
> 
>   import pydoc
>   pydoc.generate_html_docs_for(someFile)
> 
> However, it's not clear to me from the pydoc documentation which
> function calls I need to use to make this behavior work. Any ideas?

Did you try 'pydoc pydoc'? ;)

>>> import pydoc
>>> htmldoc = pydoc.HTMLDoc()
>>> htmldoc_for_pydoc = htmldoc(pydoc)
>>> print htmldoc_for_pydoc



From p.f.moore at gmail.com  Mon Jul 20 17:40:58 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Mon, 20 Jul 2009 22:40:58 +0100
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>
Message-ID: <79990c6b0907201440r5470c486j207440183514ba9@mail.gmail.com>

2009/7/20 Chris Rebert <clp2 at rebertia.com>:
> On Mon, Jul 20, 2009 at 2:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>>> x = [2,1,3]
>>>>>>> print sorted(x)[0]
>>>DB> 3
>>
>> What kind of Python produces that?
>
> Assuming you're referring to the latter example, it was added in version 2.4
> If you meant the former example, I think that's purely pseudo-Python.

I think he was referring to the fact that the result should be 1, not 3.

Paul.


From malaclypse2 at gmail.com  Mon Jul 20 17:59:08 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Mon, 20 Jul 2009 17:59:08 -0400
Subject: locale doesn' format
In-Reply-To: <4A64DC9A.3060606@nord-com.net>
References: <4A64DC9A.3060606@nord-com.net>
Message-ID: <16651e80907201459w5060ad3ex9706a1f4ec12c@mail.gmail.com>

On Mon, Jul 20, 2009 at 5:07 PM, Egon Frerich<egon.frerich at nord-com.net> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> I want to format values to the german form eg. 1.034,56 but
> locale.format() doesn't work for me.
>
> Here is a little test program:
...
> k1 = locale.format_string('%12s',k,True)

I don't think you want to be using '%s' to format numbers in your
format strings.  Instead, use '%f' to format floating point values.

As I understand it, a %s in a format string actually calls str() on
the object that you pass into the formatting function, and I don't
think that floats (or Decimal.Decimal objects) take locale into
account when you do that.

-- 
Jerry


From FSet.SLB at gmail.com  Mon Jul 20 18:07:58 2009
From: FSet.SLB at gmail.com (Scott Burson)
Date: Mon, 20 Jul 2009 15:07:58 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>

On Jul 19, 11:31?am, Frank Buss <f... at frank-buss.de> wrote:
> I don't know of a free modern and stable Lisp implementation with
> mulithreading support for Windows, with a licence with which you can use it
> in closed source commercial programs

Have you looked at ECL?

http://ecls.sourceforge.net/

I've used it only a little, so I can't vouch for its stability, but it
fits the threading and license requirements (well, some corporate
lawyers have trouble with the LGPL, but I think it's usable).

-- Scott


From corbet at lwn.net  Mon Jul 20 18:16:59 2009
From: corbet at lwn.net (Jonathan Corbet)
Date: Mon, 20 Jul 2009 16:16:59 -0600
Subject: Python Essential Reference, 4th Edition - Now Available!
In-Reply-To: <EC84D091-DABA-49B3-A141-15E753A815EA@dabeaz.com>
References: <EC84D091-DABA-49B3-A141-15E753A815EA@dabeaz.com>
Message-ID: <20090720161659.78cbf90a@bike.lwn.net>

On Sun, 19 Jul 2009 11:03:05 -0500
David Beazley <dave at dabeaz.com> wrote:

> I'm pleased to announce the release of the Python Essential Reference,
> 4th edition, now available at a bookstore near you. More than a year
> in development, this edition covers Python 2.6, Python 3, and a wide
> variety of new library modules.

And here I am still using my old, dog-eared second edition...  Any
chance of getting a copy of the 4th for an LWN review?

Thanks,

jon
-- 
Jonathan Corbet / LWN.net / corbet at lwn.net


From hniksic at xemacs.org  Mon Jul 20 18:19:36 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 21 Jul 2009 00:19:36 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <87ljmjyp3b.fsf@busola.homelinux.net>

Phillip B Oldham <phillip.oldham at gmail.com> writes:

> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>> The main reason why you need both lists and tuples is that because a tuple
>> of immutable objects is itself immutable you can use it as a dictionary
>> key.
>
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.

An application visiting files on a filesystem recursively needs a
dictionary or set keyed by (st_dev, st_ino) to make sure it doesn't
visit the same file twice.  Memoization implementation (of a cache for
results of function application) might need to use a dictionary to map
function arguments, a tuple, to the function result.


From hniksic at xemacs.org  Mon Jul 20 18:20:53 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 21 Jul 2009 00:20:53 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<mailman.3441.1248125420.8015.python-list@python.org>
Message-ID: <87hbx7yp16.fsf@busola.homelinux.net>

Chris Rebert <clp2 at rebertia.com> writes:

>>>>>>> x = [2,1,3]
>>>>>>> print sorted(x)[0]
>>>DB> 3
>>
>> What kind of Python produces that?
>
> Assuming you're referring to the latter example, it was added in version 2.4
> If you meant the former example, I think that's purely pseudo-Python.

sorted([2, 1, 3])[0] evaluates to 1, not 3.


From http  Mon Jul 20 18:22:20 2009
From: http (Paul Rubin)
Date: 20 Jul 2009 15:22:20 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
	<7xljmjguxb.fsf@ruckus.brouhaha.com>
	<7a04b07d-2dea-455f-bafd-33461ce25a1a@q11g2000yqi.googlegroups.com>
Message-ID: <7xiqhn0zc3.fsf@ruckus.brouhaha.com>

vippstar <vippstar at gmail.com> writes:
> > I don't see how to implement such a thing in my code,
> Write a function:
> 
>   (if (< x y)
>       ValueError
>       (/ x y))

I meant changing the behavior of integer division in python.

> Wouldn't that mean 3/2 would also evaluate to ValueError?

Yes, the idea was that one can take the view that integer division
should not be allowed except through a 'div' function or some such.


From ethan at stoneleaf.us  Mon Jul 20 18:34:28 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Mon, 20 Jul 2009 15:34:28 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <24543805.post@talk.nabble.com>
References: <24485116.post@talk.nabble.com>	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>	<4A5DE5E7.5070003@mrabarnett.plus.com>
	<24543805.post@talk.nabble.com>
Message-ID: <4A64F0F4.9060201@stoneleaf.us>

[fixed for bottom-posting]

Dr. Phillip M. Feldman wrote:
> MRAB-2 wrote:
> 
>>
>><snip>
>>
>>What values should 'xor' return? IMHO, if only one of the values is true
>>then it should return that value, otherwise it should return False.
>>
>>     1 xor 0 => 1
>>     0 xor 2 => 2
>>     1 xor 2 => False
>>     0 xor 0 => False
>>
>>This is because it's a Boolean operator, so it should fall back to
>>Boolean values when necessary, like 'not':
>>
>>     not 0 => True
>>     not 1 => False
>>
>>Also:
>>
>>     x and y and z => (x and y) and z
>>     x or y or z => (x or y) or z
>>
>>therefore:
>>
>>     x xor y xor z => (x xor y) xor z
>>
 > Suppose that 'xor' returns the value that is true when only one value is
 > true, and False otherwise.  This definition of xor doesn't have the 
standard
 > associative property, that is,
 >
 > (a xor b) xor c
 >
 > will not necessarily equal
 >
 > a xor (b xor c)
 >
 > To see that this is the case, let a= 1, b= 2, and c= 3.
 >
 > (a xor b) xor c
 >
 > yields 3, while
 >
 > a xor (b xor c)
 >
 > yields 1.  So, I'd prefer an xor operator that simply returns True or 
False.
 >
 > Phillip
 >

You are, of course, free to write your version however it makes sense to 
you and your team.  :)

Since the 'and' and 'or' already return objects (and objects evaluate to 
true or false), then 'xor' should behave likewise, IMO.  I expect that 
would be the case if it were ever added to the language.

~Ethan~


From martin at v.loewis.de  Mon Jul 20 18:39:11 2009
From: martin at v.loewis.de (=?UTF-8?B?Ik1hcnRpbiB2LiBMw7Z3aXMi?=)
Date: Tue, 21 Jul 2009 00:39:11 +0200
Subject: Compilation problem with Python < 2.6 and db >= 4.7
In-Reply-To: <mailman.3436.1248114395.8015.python-list@python.org>
References: <mailman.3436.1248114395.8015.python-list@python.org>
Message-ID: <4a64f210$0$8379$9b622d9e@news.freenet.de>

> Is there a way to make the bsddb module compile against db>=4.7 for python < 2.6
> (2.4.6, 2.5.4)?

I don't think so, no.

> I didn't find something on it.

If you don't want to use pybsddb either, for fear of incompatible API,
your only choice is to port _bsddb.c to the newer db versions. BSDDB
is in the tradition of both breaking the data format and the API
frequently, so we (python-dev) have given up on it.

Regards,
Martin


From niels.ellegaard at gmail.com  Mon Jul 20 18:39:24 2009
From: niels.ellegaard at gmail.com (Niels L. Ellegaard)
Date: Tue, 21 Jul 2009 00:39:24 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <86skgr0yjn.fsf@gmail.com>

Phillip B Oldham <phillip.oldham at gmail.com> writes:

> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.

If you just want a one-liner, and you don't care about speed you can
do the following (but I don't think this is considered best practice)

>>> x = [2,1,3]
>>> print list(sorted(x))   
[1, 2, 3]
>>> print x
[2, 1, 3]

     Niels


From vippstar at gmail.com  Mon Jul 20 18:48:51 2009
From: vippstar at gmail.com (vippstar)
Date: Mon, 20 Jul 2009 15:48:51 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com> 
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com> 
	<7xljmjguxb.fsf@ruckus.brouhaha.com>
	<7a04b07d-2dea-455f-bafd-33461ce25a1a@q11g2000yqi.googlegroups.com>
	<7xiqhn0zc3.fsf@ruckus.brouhaha.com>
Message-ID: <f524c9c4-70a5-4474-b0a7-56a20bd5e1a4@b14g2000yqd.googlegroups.com>

On Jul 21, 1:22?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> vippstar <vipps... at gmail.com> writes:
> > > I don't see how to implement such a thing in my code,
> > Write a function:
>
> > ? (if (< x y)
> > ? ? ? ValueError
> > ? ? ? (/ x y))
>
> I meant changing the behavior of integer division in python.
You'd either have to hack an implementation or change the standard (I
just noticed python doesn't have one).

> > Wouldn't that mean 3/2 would also evaluate to ValueError?
>
> Yes, the idea was that one can take the view that integer division
> should not be allowed except through a 'div' function or some such.
You brought up 3/2 == ValueError as a more appropriate value for the
integer division to evaluate, rather than 0. I thought you meant
specifically those kinds of divisions.


From kiorky at cryptelium.net  Mon Jul 20 18:51:42 2009
From: kiorky at cryptelium.net (kiorky)
Date: Tue, 21 Jul 2009 00:51:42 +0200
Subject: Compilation problem with Python < 2.6 and db >= 4.7
In-Reply-To: <4a64f210$0$8379$9b622d9e@news.freenet.de>
References: <mailman.3436.1248114395.8015.python-list@python.org>
	<4a64f210$0$8379$9b622d9e@news.freenet.de>
Message-ID: <4A64F4FE.805@cryptelium.net>

Martin v. L?wis a ?crit :
>> Is there a way to make the bsddb module compile against db>=4.7 for python < 2.6
>> (2.4.6, 2.5.4)?
> 
> I don't think so, no.
> 
>> I didn't find something on it.
> 
> If you don't want to use pybsddb either, for fear of incompatible API,
> your only choice is to port _bsddb.c to the newer db versions. BSDDB
> is in the tradition of both breaking the data format and the API
> frequently, so we (python-dev) have given up on it.

Yup, i understand.
I will be lazy and fall back as all packaging systems do, and keep in the
minitage packages tree both db versions.
Thanks for confirmation.

> 
> Regards,
> Martin


-- 
--
Cordialement,
KiOrKY
GPG Key FingerPrint: 0x1A1194B7681112AF




From lists at cheimes.de  Mon Jul 20 18:56:12 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 21 Jul 2009 00:56:12 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <86skgr0yjn.fsf@gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86skgr0yjn.fsf@gmail.com>
Message-ID: <h42smc$qhg$1@ger.gmane.org>

Niels L. Ellegaard wrote:
> Phillip B Oldham <phillip.oldham at gmail.com> writes:
> 
>> We often find we need to do manipulations like the above without
>> changing the order of the original list, and languages like JS allow
>> this. We can't work out how to do this in python though, other than
>> duplicating the list, sorting, reversing, then discarding.
> 
> If you just want a one-liner, and you don't care about speed you can
> do the following (but I don't think this is considered best practice)

sorted() already returns a new list not a generator as you might assume.

Christian



From piet at cs.uu.nl  Mon Jul 20 19:41:16 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 01:41:16 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<50697b2c0907201430x5fd6cb0ak6cbc75babcc293fe@mail.gmail.com>
	<mailman.3443.1248126067.8015.python-list@python.org>
Message-ID: <m2ws62ncrn.fsf@cs.uu.nl>

>>>>> Paul Moore <p.f.moore at gmail.com> (PM) wrote:

>PM> 2009/7/20 Chris Rebert <clp2 at rebertia.com>:
>>> On Mon, Jul 20, 2009 at 2:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>>>>> x = [2,1,3]
>>>>>>>>> print sorted(x)[0]
>DB> 3
>>>> 
>>>> What kind of Python produces that?
>>> 
>>> Assuming you're referring to the latter example, it was added in version 2.4
>>> If you meant the former example, I think that's purely pseudo-Python.

>PM> I think he was referring to the fact that the result should be 1, not 3.

The underlying thought was that you should copy and paste examples from
a real Python interpreter.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Mon Jul 20 20:10:55 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 17:10:55 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
	<mailman.3433.1248109750.8015.python-list@python.org>
Message-ID: <h4312f$307$1@panix3.panix.com>

In article <mailman.3433.1248109750.8015.python-list at python.org>,
D'Arcy J.M. Cain <darcy at druid.net> wrote:
>On 20 Jul 2009 09:00:33 -0700
>aahz at pythoncraft.com (Aahz) wrote:
>>
>> Out of curiosity, are there any JavaScript toolkits that generate code
>> that degrades gracefully when JavaScript is disabled?
>
>I understand what you want but I can't see how a toolkit can do that.
>How do you program "graceful?"  It seems pretty application specific.

Presumably the JS toolkit generates both code and HTML.  Actions that
normally get executed by JS should degrade to plain HTML links and form
submits (or possibly not display at all if it's a pure convenience).
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From gdamjan at gmail.com  Mon Jul 20 20:33:39 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Tue, 21 Jul 2009 02:33:39 +0200
Subject: locale doesn' format
References: <mailman.3440.1248124811.8015.python-list@python.org>
Message-ID: <30ffj6-qd6.ln1@archaeopteryx.softver.org.mk>

> I want to format values to the german form eg. 1.034,56 but
> locale.format() doesn't work for me.

seems to work here


>>> import decimal, locale
>>> locale.setlocale(locale.LC_ALL, 'mk_MK.UTF-8')
'mk_MK.UTF-8'
>>> locale.localeconv()['grouping']
[3, 3, 0]
>>> locale.localeconv()['thousands_sep']
' '
>>> locale.localeconv()['decimal_point']
','
>>> locale.format('%f', 1034.56,True)
'1 034,560000'
>>> locale.format('%d', 1034.56,True)
'1 034'



ps.
you can copy/paste the above in .txt file and then run/test it with:
python -m doctest -v  check.txt


-- 
?????? ( http://softver.org.mk/damjan/ )

  Begin...the rest is easy.



From gdamjan at gmail.com  Mon Jul 20 20:44:38 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Tue, 21 Jul 2009 02:44:38 +0200
Subject: locale doesn' format
References: <mailman.3440.1248124811.8015.python-list@python.org>
	<30ffj6-qd6.ln1@archaeopteryx.softver.org.mk>
Message-ID: <mkffj6-1f6.ln1@archaeopteryx.softver.org.mk>



>> I want to format values to the german form eg. 1.034,56 but
>> locale.format() doesn't work for me.
> 
> seems to work here

In 2.6 this is good too:

>>> import decimal, locale
>>> locale.setlocale(locale.LC_ALL, 'mk_MK.UTF-8')
>>> '{0:n}'.format(1234.56)
'1 234,56'


-- 
?????? ( http://softver.org.mk/damjan/ )

A: Because it reverses the logical flow of conversation.
Q: Why is top posting frowned upon?



From davea at ieee.org  Mon Jul 20 20:47:56 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 20 Jul 2009 20:47:56 -0400
Subject: Design question.
In-Reply-To: <68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
References: <4dce44e2-3911-4313-8cf1-2f14634426eb@k30g2000yqf.googlegroups.com>	<mailman.3423.1248095131.8015.python-list@python.org>
	<68149452-d139-4866-bf1b-5e1c49fdd479@w41g2000yqb.googlegroups.com>
Message-ID: <4A65103C.4010401@ieee.org>

Lacrima wrote:
> On Jul 20, 4:05 pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
> wrote:
>   
>> Lacrima wrote:
>>     
>>> Hello!
>>>       
>>> I am newbie in python and I have really simple question, but I need
>>> your advice to know how to do best.
>>> I need to store a number of dictionaries in certain place. I've
>>> decided to store them in a separate module.
>>> Like this:
>>> dicts.py
>>> -----------------------
>>> dict1 =....}
>>> dict2 =....}
>>> dict3 =....}
>>>       
>>> Then, when I need any dictionary, I can access it:
>>> import dicts
>>> dicts.dict1
>>>       
>> <snip>
> Hi, Jean-Michel!
>
> Thanks for your answer.
> I am not going to have names like dicts.py and dict1,dict2. That was
> just example. I wanted to know if it is correct to have dictionaries
> on a module level. Now I know that this is correct. I want to collect
> in one module a number of dictionaries, every of which describes a
> separate web service. And my function in another module will import
> required dictionary, depending on what web service should be used.
> Thanks again for the help.
>
> With regards,
> Max.
> (sorry if my English isn't very proper)
>
>   
It makes a lot of sense to store several dictionaries in a module, if 
they describe parallel things, or alternate ways of accessing something 
(like web services).

However, you might want to consider how they'll be accessed.  If another 
module is going to "import required dictionary," then you have some 
means of selection.  Perhaps that selection should be in the same 
module, or at least the data structure to select it should be in the 
same module.

Let's say you have four choices right now.  And you add a fifth later.  
Do you want to have to edit both the "function in the other module" as 
well as this module?

This is similar to a feature that some programs have, "plug-ins."   
There a customer can add an additional runtime just by dropping a new 
.py file in the appropriate directory, and the program will find it and 
add it to its "list of features."

So I'm just suggesting you figure out how the program might evolve, and 
set up the data so changes may be localized, if practical.  This turns 
out usually to be parallel to the notion of naming things and grouping 
them by similarity of functionality.

DaveA




From sajmikins at gmail.com  Mon Jul 20 20:56:26 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Mon, 20 Jul 2009 17:56:26 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7xljmk8q1m.fsf@ruckus.brouhaha.com>
Message-ID: <6348dcb8-bfc1-446e-b7bf-28657e2b607e@j32g2000yqh.googlegroups.com>

On Jul 19, 2:51 pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Calroc <forman.si... at gmail.com> writes:
> > I'm engaged presently in starting a school to teach programming from
> > the ground up, based roughly on the curriculum outlined in the article
> > I mentioned. ...
> > I'm excited about formal methods because one, I just heard about them,
>
> Formal methods are a big and complicated subject.  Right after you
> heard about them is probably not the best time to start teaching them.
> Better get to understand them yourself first.

Very good point.

But I'm glad it's there to study, these are wheels I don't have to
invent for myself.

~Simon


From sajmikins at gmail.com  Mon Jul 20 20:57:05 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Mon, 20 Jul 2009 17:57:05 -0700 (PDT)
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org> 
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com> 
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7cimf0F27u23eU1@mid.individual.net>
Message-ID: <11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>

On Jul 20, 4:00 am, greg <g... at cosc.canterbury.ac.nz> wrote:
> Calroc wrote:
> > It may be that flawless software is an unreachable asymptote, like the
> > speed of light for matter, but I'm (recently!) convinced that it's a
> > goal worthy of exploration and effort.
>
> Seems to me that once you get beyond the toy program
> stage and try to apply correctness proving to real
> world programming problems, you run up against the
> problem of what exactly you mean by "correct".
>
> Once the requirements get beyond a certain level of
> complexity, deciding whether the specifications
> themselves are correct becomes just as difficult as
> deciding whether the program meets them.

I agree.  You could prove that a game renders geometry without
crashing, but not that it's fun.  Or in an accounting package you
could prove that it never loses a cent in tracking accounts and
payments, or that its graph-rendering code does correctly render data
(without introducing artifacts, for instance), but not that it will
let you notice trends.

> Then there's the fact that very often we don't
> even know what the exact requirements are, and it's
> only by trying to write and use the program that
> we discover what they really are -- or at least,
> get a better idea of what they are, because the
> process is usually iterative, with no clear end
> point.

Aye, if you're still exploring your solution space your requirements
are perforce somewhat nebulous.

> So in theory, correctness proofs are a fine idea,
> and might even be doble on a small scale, but the
> real world is huge and messy!

Very true, but I think it is still worthy to build larger systems from
proven components combined in provably correct ways, at least to the
extent possible.

> > Just because it's unattainable doesn't make it undesirable.  And who
> > knows? Maybe the horse will learn to sing.
>
> Striving to find ways of writing less bugs is a
> worthy goal, but I think of it more in terms of
> adopting patterns of thought and programming that
> make it more likely you will write code that does
> what you had in mind, rather than a separate
> "proof" process that you go through afterwards.

I would consider formal methods exactly "patterns of thought and
programming that make it more likely you will write code that does
what you had in mind", in fact that's why I'm excited about them.

My understanding (so far) is that you (hope to) /derive/ correct code
using formal logic, rather than writing code and then proving its
soundness.

The real win, IMO, is teaching computers as a logical, mathematical
activity (that can certainly depart for realms less rigorously
defined.)

I think anyone who can spontaneously solve a Sudoku puzzle has enough
native grasp of "formal" methods of reasoning to learn how to derive
working programs logically.  Making the formal methods explicit gives
you the strongest available confidence that you are reasoning, and
programming, correctly.

This is not to say that "incorrect" (or unproven or unprovable)
programs are never useful or necessary.  However, I do feel that it's
better to learn the "correct" way, and then introduce ambiguity, than
to simply throw e.g. Java at some poor student and let them find solid
ground "catch as catch can".


~Simon



From darcy at druid.net  Mon Jul 20 21:18:28 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Mon, 20 Jul 2009 21:18:28 -0400
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
In-Reply-To: <h4312f$307$1@panix3.panix.com>
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
	<mailman.3433.1248109750.8015.python-list@python.org>
	<h4312f$307$1@panix3.panix.com>
Message-ID: <20090720211828.88876711.darcy@druid.net>

On 20 Jul 2009 17:10:55 -0700
aahz at pythoncraft.com (Aahz) wrote:
> >I understand what you want but I can't see how a toolkit can do that.
> >How do you program "graceful?"  It seems pretty application specific.
> 
> Presumably the JS toolkit generates both code and HTML.  Actions that
> normally get executed by JS should degrade to plain HTML links and form
> submits (or possibly not display at all if it's a pure convenience).

As I said, I do understand what you are after but I still think it is a
judgement call.  What defines "convenience?"  How does the library know
what is essential and what is pretty?

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From ebonak at hotmail.com  Mon Jul 20 21:53:59 2009
From: ebonak at hotmail.com (Esmail)
Date: Mon, 20 Jul 2009 21:53:59 -0400
Subject: comments? storing a function in an object
In-Reply-To: <op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
References: <mailman.3430.1248106983.8015.python-list@python.org>	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
	<op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A651FB7.1030602@hotmail.com>

Gabriel Genellina wrote:
 >
> If you follow the above suggestions, you'll see that your Function class 
> becomes almost useless: a normal function already IS an object, so you 
> don't have to wrap it inside ANOTHER object unless you need very special 
> features.

Hello Gabriel,

In general I would agree with you, but in my specific case
I want so store some additional meta-data with each function, such
as the valid range for input values, where the max or minimum are located,
the name/source for the function etc. I am creating list of functions
for use in testing optimization code, so it seems best to store this
data along with the function I am going to optimize in order to verify
the results for a given range (for instance).

Esmail




From http  Mon Jul 20 21:54:54 2009
From: http (Paul Rubin)
Date: 20 Jul 2009 18:54:54 -0700
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7xljmk8q1m.fsf@ruckus.brouhaha.com>
	<6348dcb8-bfc1-446e-b7bf-28657e2b607e@j32g2000yqh.googlegroups.com>
Message-ID: <7xws627qc1.fsf@ruckus.brouhaha.com>

Simon Forman <sajmikins at gmail.com> writes:
> But I'm glad it's there to study, these are wheels I don't have to
> invent for myself.

http://dwheeler.com/essays/high-assurance-floss.html

might be an interesting place to start.


From ebonak at hotmail.com  Mon Jul 20 22:01:45 2009
From: ebonak at hotmail.com (Esmail)
Date: Mon, 20 Jul 2009 22:01:45 -0400
Subject: comments? storing a function in an object
In-Reply-To: <3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
Message-ID: <4A652189.2000607@hotmail.com>

Hi Francesco,

Those were great suggestions!

Re 1: I used the __doc__ attribute to eliminate the parameter in the
       constructor as you suggested. Also, much easier to specify the
       character string with the actual function than later to match it
       up like I was.

class Function(object):
     """ class to represent a function """

     def __init__(self, fn, num_vars):
         """ the function, its string representation, and the number of 
variables """
         self.fn = fn
         self.fn_str = fn.__doc__
         self.num_vars = num_vars


Re 2: I will need to read up on __call__ to see how to use it here ..


Re 3: I think I still need to have my own exception handler as I am
       using the 'extended call syntax' now (I just learned about this
       yesterday) and I will always just supply one argument, the
       list. Or perhaps my custom exception will be superfluous once I
       figure out __call__ ..?


Thank you for taking the time to help, always good to learn new things.

Esmail



From aahz at pythoncraft.com  Mon Jul 20 22:53:08 2009
From: aahz at pythoncraft.com (Aahz)
Date: 20 Jul 2009 19:53:08 -0700
Subject: are user defined classes hashable?
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net>
	<mailman.3396.1248018412.8015.python-list@python.org>
	<373d6c69-6965-4a88-bdd2-8028ef850bf8@k6g2000yqn.googlegroups.com>
Message-ID: <h43aik$oct$1@panix3.panix.com>

In article <373d6c69-6965-4a88-bdd2-8028ef850bf8 at k6g2000yqn.googlegroups.com>,
Hyuga  <hyugaricdeau at gmail.com> wrote:
>
>Regardless, Nicolas's example can be applied to the class too:
>
>>>> class Foo(object):
>	pass
>
>>>> hash(Foo)
>11443104
>>>> id(Foo)
>11443104
>
>class objects are just objects of type 'type'.

Not quite.  They certainly default that way, but changing the metaclass
changes a class's type::

class M(type): 
    pass

class C(object): 
    pass

class C2(object):
    __metaclass__ = M

print type(C)
print type(C2)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From pavlovevidence at gmail.com  Mon Jul 20 23:53:53 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Mon, 20 Jul 2009 20:53:53 -0700 (PDT)
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
Message-ID: <f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com>

On Jul 20, 9:22?am, Esmail <ebo... at hotmail.com> wrote:
> def funct1(x):
> ? ? ?''' small test function '''
> ? ? ?return x * x
>
> def funct2(x, y):
> ? ? ?''' small test function '''
> ? ? ?return x + y
>
> def funct3(x):
> ? ? ?''' small test function '''
> ? ? ?return 1000 + (x*x + x) * math.cos(x)
>
> def main():
> ? ? ?""" main method """
> ? ? ?print 'in main'
>
> ? ? ?fn1 = Function(funct1, 'x * x', 1)
> ? ? ?fn2 = Function(funct2, 'x + y', 2)
> ? ? ?fn3 = Function(funct3, '1000 + (x*x + x) * cos(x)', 1)


If you are defining all of the functions are in-line like this (and I
assume you are because you seem to need a function object), I'd just
exec the string representation.  This is to support the DRY
principle.  You could do something like this:


class Function(object):
    def __init__(self,args,body):
        ns = {}
        exec '''def func(%s): return %s''' in ns
        self.fn = ns['func']
        self.fn_str = body
        self.num_vars = args.count(',')+1


You have to be REALLY REALLY careful not to pass any user-supplied
data to it if this is a server running on your computer, of course.
(If it's an application running on the user's computer it doesn't
matter.)

Still wouldn't be a bad idea to pass it through some kind of validator
for extra protection.


Carl Banks


From boyd.blackwell at gmail.com  Mon Jul 20 23:56:51 2009
From: boyd.blackwell at gmail.com (bdb112)
Date: Mon, 20 Jul 2009 20:56:51 -0700 (PDT)
Subject: clean way prepend an element to a numpy array
Message-ID: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>

If I want to add an element at the beginning of an array, it seems
like I must make a list, insert in place, then make an array again.

Of course, lists can be efficient too, and the insert() funtion works
nicely in that case, but sometimes arrays are the best choice

e.g.
x=array([1,2,3])
# to put the element 0 at the head of the array
listx=list(x)
listx.insert(0,0)
x=array(listx)
# this extra effort distracts from the clarity of the code, and must
slow things a little.

# While I appreciate that array operations that cause memory re-
allocation and copying are to be
#  avoided if at all possible, sometimes this is the best compromise
between clarity and efficiency

# A nicer piece of code would be

x.insert(0,0)
#or
x.prepend(0)

# It is a little easier to grow an array at the end (if it is not
referenced)
x.resize(4)

I saw this interest syntax on this site
x[:0]=0

I guess that is cute, but could be confusing....(and doesn't work)


From ben+python at benfinney.id.au  Tue Jul 21 00:13:55 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 21 Jul 2009 14:13:55 +1000
Subject: clean way prepend an element to a numpy array
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
Message-ID: <87eisaad18.fsf@benfinney.id.au>

bdb112 <boyd.blackwell at gmail.com> writes:

> If I want to add an element at the beginning of an array, it seems
> like I must make a list, insert in place, then make an array again.

The NumPy ?ndarray? type (which is what you get by default from the
?array? factory function) is a far more complex type than (and is not
derived from) the Python list.

For manipulating them, you'll want to study the NumPy documentation
<URL:http://docs.scipy.org/doc/numpy/reference/arrays.ndarray.html>.

-- 
 \     ?Are you pondering what I'm pondering?? ?I think so, Brain, but |
  `\        I don't think Kay Ballard's in the union.? ?_Pinky and The |
_o__)                                                           Brain_ |
Ben Finney


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 00:31:04 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 01:31:04 -0300
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
	<op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
	<4A651FB7.1030602@hotmail.com>
Message-ID: <op.uxehh2rox6zn5v@gabriel.cpe.telecentro.net.ar>

En Mon, 20 Jul 2009 22:53:59 -0300, Esmail <ebonak at hotmail.com> escribi?:

> Gabriel Genellina wrote:
>  >
>> If you follow the above suggestions, you'll see that your Function  
>> class becomes almost useless: a normal function already IS an object,  
>> so you don't have to wrap it inside ANOTHER object unless you need very  
>> special features.
>
> Hello Gabriel,
>
> In general I would agree with you, but in my specific case
> I want so store some additional meta-data with each function, such
> as the valid range for input values, where the max or minimum are  
> located,
> the name/source for the function etc. I am creating list of functions
> for use in testing optimization code, so it seems best to store this
> data along with the function I am going to optimize in order to verify
> the results for a given range (for instance).

You can store all meta-data in the function itself:

py> def triangle(b, h):
...   "area of triangle: b*h/2"
...   return b*h/2
...
py> triangle.foo = "some value"
py> triangle.foo
'some value'

Python already knows some properties:

py> triangle.func_code.co_argcount
2
py> triangle.func_doc
'area of triangle: b*h/2'
py> triangle.__doc__
'area of triangle: b*h/2'

You may use this variant of Carl Banks proposal - this is a factory  
function that returns new function objects:

def inline_function_factory(name, args, expr):
   ns = {}
   exec '''def %s(%s):
             %r
             return %s''' % (
     name, args, expr, expr) in ns
   function = ns[name]
   return function

py> sqr = inline_function_factory("square", "x", "x*x")
py> sqr(3)
9
py> sqr.__doc__
'x*x'
py> sqr
<function square at 0x00B46770>

Wrapping a function object isn't necesarily bad, but perhaps you're doing  
things more complicated than should be.

-- 
Gabriel Genellina



From smolds at orcasoul.com  Tue Jul 21 00:33:25 2009
From: smolds at orcasoul.com (OrcaSoul)
Date: Mon, 20 Jul 2009 21:33:25 -0700 (PDT)
Subject: Mechanize not recognized by py2exe
In-Reply-To: <op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>
References: <4A60C81F.7080707@comcast.net>
	<op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <24581545.post@talk.nabble.com>



Gabriel Genellina-7 wrote:
> 
> En Fri, 17 Jul 2009 15:51:11 -0300, Stephen M. Olds <smolds at comcast.net>  
> escribi?:
> 
>> I have a Python script getData.py that uses Mechanize, and runs fine  
>> under the
>> interpreter. It was installed using easy_install - and the install  
>> seemed to
>> indicate it was completed.
>>
>> The problem is, when I try to compile it using py2exe while in the  
>> folder of the
>> script, and using the run line command:
>>
>> python getData.py py2exe
>>
>> I get the warning: "Import error: No Module named mechanize"...
>>
>> I checked the environmental path and find the following:
>> %SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program  
>> Files (x86)\Python;C:\Python25\Lib\site-packages;C:\Program
>> Files (x86)\Common Files\Adobe\AGL
> 
> The system PATH is irrelevant here - it's only used by Windows to locate  
> the Python executable. I don't see a reason to list  
> C:\Python25\Lib\site-packages here.
> You're mostly interested in sys.path instead (that is, the 'path'  
> attribute in the 'sys' Python module)
> 
>> I did a search for mechanize and find an egg file in  
>> C:\Python25\Lib\site-packages
>> named mechanize-0.1.7b-py2.5.
>>
>> Not really understanding the "egg" thing, what do I have here that needs  
>> to be
>> done?
> 
> I'm not an egg expert either, and I try to avoid them as a plague. But I  
> *think* you can delete the .egg and re-install it using easy_install with  
> the -Z option.
> 
> -- 
> Gabriel Genellina
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

Gabriel, that was the kick in the pants I needed! Thanks - after over a week
searching through the same 15 web pages these old eyes simply blurred over
and I missed that one...I had tried the -a option, but that's what got me
the eggs...

So, thanks for the help...it's too late to name my first born after you, but
I did have a cat named Gabriel - she was a great cat!

Stephen

-- 
View this message in context: http://www.nabble.com/Mechanize-not-recognized-by-py2exe-tp24540012p24581545.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From fb at frank-buss.de  Tue Jul 21 00:57:39 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 06:57:39 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
Message-ID: <61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>

Scott Burson wrote:

> Have you looked at ECL?
> 
> http://ecls.sourceforge.net/
> 
> I've used it only a little, so I can't vouch for its stability, but it
> fits the threading and license requirements (well, some corporate
> lawyers have trouble with the LGPL, but I think it's usable).

I didn't tried it myself, but looks like it is not very stable:

http://www.mail-archive.com/application-builder at lispniks.com/msg01069.html

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From astan.chee at al.com.au  Tue Jul 21 01:02:57 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 21 Jul 2009 15:02:57 +1000
Subject: ignore special characters in python regex
Message-ID: <4A654C01.2000508@al.com.au>

Hi,
I'm reading text from a file (per line) and I want to do a regex using 
these lines but I want the regex to ignore any special characters and 
treat them like normal strings.
Is there a regex function that can do this?
Here is what I have so far:
fp = open('file.txt','r')
notes = fp.readlines()
fp.close()
strin = "this is what I want"
for note in notes:
     if re.search(r""+ str(note) + "",strin):
           print "Found " + str(note) + " in " + strin

Thanks for any help


From fb at frank-buss.de  Tue Jul 21 01:08:41 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 07:08:41 +0200
Subject: any suggestions to synchronize typed text and speech ?
References: <mailman.3406.1248034495.8015.python-list@python.org>
Message-ID: <azifuk04513x$.1wmls13dctrxz$.dlg@40tude.net>

Stef Mientki wrote:

> Here the problem part:
> I need to synchronize the typed text with the sound during playback.
> So if I click somewhere in the sound recording,
> the line of text, typed that moment should be highlighted.
> And vise versa, if the cursor in the text is moved and some special key 
> is pressed,
> the sound starting 10 or 20seconds earlier should be playbacked.

You could use some screen recording tools, e.g.
http://www.techsmith.com/camtasia.asp on Windows. Most tools allows you to
record speech while recording the screen.

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From doomster at knuut.de  Tue Jul 21 01:16:10 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Tue, 21 Jul 2009 07:16:10 +0200
Subject: C-API, tp_dictoffset vs tp_members
Message-ID: <7cl194F28ojoqU1@mid.uni-berlin.de>

Hi!

When would I use PyObject_SetAttrString/tp_dictoffset instead of tp_members? 

I have a predefined set of members, some of which are optional. The problem 
I had with an embedded dictionary was that I can't see its elements using 
"dir()". Now I just converted to using tp_members, and it still seems to 
work correctly for the cases I tested. Even better, I can declare the fields 
as read-only then and add doc-strings. So, I wonder, what made the original 
author[2] use tp_dictoffset instead? 

In case you wonder, I'm looking at the Python bindings for GDB[1], file 
gdb/python/python-type.c, struct field_object.


Thanks!

Uli


[1] http://sourceware.org/gdb/wiki/PythonGdb
[2] Yes I could ask them, but I'd like to get an understanding of the pros 
and cons.




From fb at frank-buss.de  Tue Jul 21 01:18:01 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 07:18:01 +0200
Subject: ignore special characters in python regex
References: <mailman.3456.1248152587.8015.python-list@python.org>
Message-ID: <13459wwzhbzoo$.jei131n3o527.dlg@40tude.net>

Astan Chee wrote:

> I'm reading text from a file (per line) and I want to do a regex using 
> these lines but I want the regex to ignore any special characters and 
> treat them like normal strings.
> Is there a regex function that can do this?

Maybe re.escape helps?

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From boyd.blackwell at gmail.com  Tue Jul 21 01:41:13 2009
From: boyd.blackwell at gmail.com (bdb112)
Date: Mon, 20 Jul 2009 22:41:13 -0700 (PDT)
Subject: clean way prepend an element to a numpy array
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
	<87eisaad18.fsf@benfinney.id.au>
Message-ID: <608f857f-3925-44db-9e5e-8969b6a116af@b25g2000prb.googlegroups.com>

On Jul 21, 2:13?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> bdb112 <boyd.blackw... at gmail.com> writes:
> > If I want to add an element at the beginning of an array, it seems
> > like I must make a list, insert in place, then make an array again.
>
> The NumPy ?ndarray? type (which is what you get by default from the
> ?array? factory function) is a far more complex type than (and is not
> derived from) the Python list.
>
> For manipulating them, you'll want to study the NumPy documentation
> <URL:http://docs.scipy.org/doc/numpy/reference/arrays.ndarray.html>.
>

Yes, I had had a look through that - nothing there that allows writing
a succint
clear statement (except for my .resize example in the original post),
although if efficiency was
a concern, then maybe resize and shift right, but that would really
obscure the code.



From sjmachin at lexicon.net  Tue Jul 21 02:01:38 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 20 Jul 2009 23:01:38 -0700 (PDT)
Subject: ignore special characters in python regex
References: <mailman.3456.1248152587.8015.python-list@python.org>
Message-ID: <ce9a527a-767f-481a-9a48-00492ae7a88f@g1g2000pra.googlegroups.com>

On Jul 21, 3:02?pm, Astan Chee <astan.c... at al.com.au> wrote:
> Hi,
> I'm reading text from a file (per line) and I want to do a regex using
> these lines but I want the regex to ignore any special characters and
> treat them like normal strings.
> Is there a regex function that can do this?

It would help if you were to say

(1) what "ignore ... characters" means -- pretend they don't exist?
(2) what are "special chararacters" -- non-alphanumeric?
(3) what "treat them like normal strings" means
(4) how you expect these special characters to be (a) ignored and (b)
"treated like normal strings" /at the same time/.

Cheers,
John


From cmpython at gmail.com  Tue Jul 21 02:11:33 2009
From: cmpython at gmail.com (Che M)
Date: Mon, 20 Jul 2009 23:11:33 -0700 (PDT)
Subject: any suggestions to synchronize typed text and speech ?
References: <mailman.3406.1248034495.8015.python-list@python.org>
Message-ID: <9eb00b5c-f51b-45ab-9e1a-1b1691a7e538@h18g2000yqj.googlegroups.com>

On Jul 19, 4:15?pm, Stef Mientki <stef.mien... at gmail.com> wrote:
> hello,
>
> I'm using Scintilla as a wxPython widget with great pleasure.
> I now have an application where I want to make notes during a conversation,
> but also want to record the speech during that conversation.
> I'm using Scintilla as a wxPython widget for editing and PyAudio for the
> speech recording,
> until so far everything works fine.
>
> Here the problem part:
> I need to synchronize the typed text with the sound during playback.
> So if I click somewhere in the sound recording,
> the line of text, typed that moment should be highlighted.
> And vise versa, if the cursor in the text is moved and some special key
> is pressed,
> the sound starting 10 or 20seconds earlier should be playbacked.
>
> I though of adding bookmarks (because these are fixed in the text), and
> keep a list of bookmarks and sound pointers.
> This idea should work, but there are only 31 bookmarks.
>
> Any other suggestions ?
>
> thanks,
> Stef Mientki

Stef, it occurs to me now that you might be useful to look at
Transana:
http://www.transana.org/

>From their site:

Transana is software for professional researchers who want to
analyze digital video or audio data. Transana lets you analyze
and manage your data in very sophisticated ways. Transcribe it,
identify analytically interesting clips, assign keywords to clips,
arrange and rearrange clips, create complex collections of
interrelated clips, explore relationships between applied keywords,
and share your analysis with colleagues.

It is written in Python, uses Scintilla, and is open source (GPL):
http://www.transana.org/developers/index.htm

Che


From ivlenin at gmail.com  Tue Jul 21 02:24:05 2009
From: ivlenin at gmail.com (I V)
Date: 21 Jul 2009 08:24:05 +0200
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<3a2b1cd7-f337-4a99-8a51-004897ac2247@v20g2000yqm.googlegroups.com>
	<op.uxdyd8t1x6zn5v@lepton.softlabbsas.com.ar>
	<mailman.3452.1248141246.8015.python-list@python.org>
Message-ID: <4a655f05$1@news.x-privat.org>

On Mon, 20 Jul 2009 21:53:59 -0400, Esmail wrote:
> In general I would agree with you, but in my specific case I want so
> store some additional meta-data with each function, such as the valid
> range for input values, where the max or minimum are located, the
> name/source for the function etc. I am creating list of functions for
> use in testing optimization code, so it seems best to store this data
> along with the function I am going to optimize in order to verify the
> results for a given range (for instance).

You can set attributes on functions, so if your class is just storing 
this data, rather than altering the behavior of the function, you may be 
able to just use a function:

def f(x, y):
	"x * y"
	return x * y

f.arguments_max = [1000, 255]

A function also already knows how many arguments it takes, which you can 
access as f.func_code.co_argcount


From jayshree06comp at gmail.com  Tue Jul 21 02:29:06 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Mon, 20 Jul 2009 23:29:06 -0700 (PDT)
Subject: python function for retrieving key and encryption
Message-ID: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>

M2Crypto package not showing the 'recipient_public_key.pem' file at
linux terminal .how do i get/connect with recipient public key.

exactly i need to check how can i open this file through linux
commands.

import M2Crypto def encrypt(): recip = M2Crypto.RSA.load_pub_key(open
('recipient_public_key.pem','rb').read()) print recip; plaintext =
whatever i need to encrypt msg = recip.public_encrypt
(plaintext,RSA.pkcs1_padding) print msg;

after calling the function its not giving any output and even any
error

i also tried as 'Will' said

pk = open('public_key.pem','rb').read() print pk; rsa =
M2Crypto.RSA.load_pub_key(pk)

whats the mistake i am not getting .will somebody help me out.
is something wrong in opening 'recipient_public_key.pem'. is M2Crypto
contain this file inbuilt .from where this file taking public key of
the recipient i'. what this file contain and how it will work .should
i need to create such a file for my purpose.if it is then how can i
create this  and how it will retrieve the key,where i recognize my
recipient to get his public key .is something like database at server.

please give me a quick response......
looking for your answer.


From jackdied at gmail.com  Tue Jul 21 02:42:02 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Tue, 21 Jul 2009 02:42:02 -0400
Subject: Why aren't OrderedDicts comparable with < etc?
In-Reply-To: <02746997$0$5185$c3e8da3@news.astraweb.com>
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<mailman.3202.1247728343.8015.python-list@python.org>
	<SfY7m.5466$875.1940@newsfe20.ams2>
	<mailman.3317.1247864411.8015.python-list@python.org>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
	<02746997$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <b8e622740907202342r5b0f7367h29fd62f4b15e3da0@mail.gmail.com>

On Mon, Jul 20, 2009 at 10:00 AM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Mon, 20 Jul 2009 09:34:24 +0000, Sion Arrowsmith wrote:
>
>> Terry Reedy ?<tjreedy at udel.edu> wrote:
>>>Sion Arrowsmith wrote:
>>>> Jack Diederich ?<jackdied at gmail.com> wrote:
>>>>> It isn't an OrderedDict thing, it is a comparison thing. ?Two regular
>>>>> dicts also raise an error if you try to LT them.
>>>> Python 2.5.2
>>>>>>> d1 = dict((str(i), i) for i in range (10)) d2 = dict((str(i), i)
>>>>>>> for i in range (20)) d1 < d2
>>>> True
>>>Try reversing the definitions of d1 and d2. The dicts are probably being
>>>compared by id (address), which is the 2.x CPython default.
>>
>> Like this?
>>
>>>>> d1 = dict((str(i), i) for i in range (20))
>>>>> d2 = dict((str(i), i) for i in range (10))
>>>>> d1 < d2
>> False
>>>>> id(d1) < id(d2)
>> True
>>
>> I didn't know that comparison for anything other than equality defaulted
>> to using id. That really is rather broken, and I'm glad 3.0 fixed it.
>
>
> I don't think comparisons other than equality use id. That would be
> rather insane. If anyone can demonstrate such comparisons in a built-in
> or standard library class, I'd like to see it.
>
>
> For the record, dicts have been comparable with < and > since at least
> Python 1.5:
>
> $ python1.5
> Python 1.5.2 (#1, Apr ?1 2009, 22:55:54) ?[GCC 4.1.2 20070925 (Red Hat
> 4.1.2-27)] on linux2
> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>>
>>>> {1: 'a', 2: 'b'} < {2: 'b', 3: 'a'}
> 1
>
>
> Reading the docs:
>
> http://docs.python.org/library/stdtypes.html#comparisons
> http://docs.python.org/library/stdtypes.html#mapping-types-dict
>
> I can only suggest that dicts compare in an arbitrary but consistent
> fashion.

I should have specified 3.x but since we were talking about
OrderedDicts (only in 3.1) I didn't say it explicitly.   Earlier
versions of python were very permissive with comparisons -- it was
rare that any cmp() raised an error and the ultimate fallback was on
the object's id.  This is one of the non-backwards compatible changes
in 3k.  Now comparing two of the same thing that don't have an obvious
ordering is an error.  Is a dict "greater than" if it has a larger
size?  if its max key is larger?  what does "max key" mean when the
keys aren't even comparable?.  Comparing things that aren't extremely
similar is an error now also.

-Jack


From astan.chee at al.com.au  Tue Jul 21 02:59:16 2009
From: astan.chee at al.com.au (Astan Chee)
Date: Tue, 21 Jul 2009 16:59:16 +1000
Subject: ignore special characters in python regex
In-Reply-To: <ce9a527a-767f-481a-9a48-00492ae7a88f@g1g2000pra.googlegroups.com>
References: <mailman.3456.1248152587.8015.python-list@python.org>
	<ce9a527a-767f-481a-9a48-00492ae7a88f@g1g2000pra.googlegroups.com>
Message-ID: <4A656744.7050908@al.com.au>

I think the re.escape did the trick.
to answer your questions:
By "ignore" i meant instead of using non-alphanumeric characters that 
have special significance in regular expression (e.g. [|\]) and treat 
them as normal strings (i.e preceded by \), but since I don't know all 
the characters in regular expression that have special significance, I 
don't know which ones to add a '\' infront of.
Thanks anyway

John Machin wrote:
> On Jul 21, 3:02 pm, Astan Chee <astan.c... at al.com.au> wrote:
>   
>> Hi,
>> I'm reading text from a file (per line) and I want to do a regex using
>> these lines but I want the regex to ignore any special characters and
>> treat them like normal strings.
>> Is there a regex function that can do this?
>>     
>
> It would help if you were to say
>
> (1) what "ignore ... characters" means -- pretend they don't exist?
> (2) what are "special chararacters" -- non-alphanumeric?
> (3) what "treat them like normal strings" means
> (4) how you expect these special characters to be (a) ignored and (b)
> "treated like normal strings" /at the same time/.
>
> Cheers,
> John
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/10095d91/attachment-0001.html>

From joswig at lisp.de  Tue Jul 21 03:00:16 2009
From: joswig at lisp.de (Rainer Joswig)
Date: Tue, 21 Jul 2009 00:00:16 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
	<61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>
Message-ID: <f2361d71-dd8b-45cc-89fc-edf39e57197a@24g2000yqm.googlegroups.com>

On 21 Jul., 06:57, Frank Buss <f... at frank-buss.de> wrote:
> Scott Burson wrote:
> > Have you looked at ECL?
>
> >http://ecls.sourceforge.net/
>
> > I've used it only a little, so I can't vouch for its stability, but it
> > fits the threading and license requirements (well, some corporate
> > lawyers have trouble with the LGPL, but I think it's usable).
>
> I didn't tried it myself, but looks like it is not very stable:
>
> http://www.mail-archive.com/application-buil... at lispniks.com/msg01069.html


I'm not sure if it is fair to post a reference to a single
post by someone without context and without having used ECL.
If there are stability problems, people can report to the
ECL mailing list. The maintainers are very active.

Frank, I have seen you constructive and posting code a year ago.
What happened? Several messages of yours I've seen here are now
going in the direction of been mostly useless. I thought
you could do better.

If you are no longer interested in Lisp with no first hand usage,
why not switch to comp.lang.misc or some other random place?


From hv at tbz-pariv.de  Tue Jul 21 03:03:23 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Tue, 21 Jul 2009 09:03:23 +0200
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <7cl7hrF28lsb2U1@mid.individual.net>

casebash schrieb:
> Hi,
> 
> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

Hi,

you could use a list of characters. It would not be difficult to
implement this as a class with all fancy methods like startswith() ...

  Thomas

-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From googler.1.webmaster at spamgourmet.com  Tue Jul 21 03:22:27 2009
From: googler.1.webmaster at spamgourmet.com (moerchendiser2k3)
Date: Tue, 21 Jul 2009 00:22:27 -0700 (PDT)
Subject: PIL for OSX 64bit
Message-ID: <e0564f03-f736-4d0f-8c50-e1bce0eb55f8@r2g2000yqm.googlegroups.com>

Hi,

I have a problem with Python and the Python Image Library to get it
work on OSX 64 bit. Maybe anyone can help me? I started Python in 64
bit mode and called Image.open(...).load() and got:

ImportError: The _imaging C module is not installed

Yes, it seems PIL is not available in 64 bit on my system, but I can't
compile it in any way. Is there a tutorial or something like that
which explains how I can compile it in 64 bit? I found a workaround
where I added this function to the setup.py

OrigExtension = Extension
def Extension(*args, **kwargs):
extra_args = ['-arch', 'x86_64']
kwargs['extra_compile_args'] = extra_args + kwargs.get
('extra_compile_args', [])
kwargs['extra_link_args'] = extra_args + kwargs.get('extra_link_args',
[])
return OrigExtension(*args, **kwargs)

without success. Can anyone help me? Thanks...


Cheers, Googler


From dtgeadamo at yahoo.com  Tue Jul 21 03:27:45 2009
From: dtgeadamo at yahoo.com (sightseer)
Date: Tue, 21 Jul 2009 00:27:45 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
Message-ID: <2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>

On Jul 20, 5:25?pm, "David Adamo Jr." <dtgead... at yahoo.com> wrote:
> On Jul 20, 5:14?pm, Tim Golden <m... at timgolden.me.uk> wrote:
>
>
>
> > mistersexy wrote:
> > > On Jul 20, 3:03 pm, Tim Golden <m... at timgolden.me.uk> wrote:
> > >> mistersexy wrote:
> > >>> I am trying to create a Windows service in Python using pywin32. I do
> > >>> not want this service to run under a user account. I want this service
> > >>> to be able to run as a LocalService, NetworkService and the like. How
> > >>> do I specify this using the win32 library? Thanks, everyone.
> > >> When you "install" the service, using the HandleCommandLine
> > >> option, specify --username= and --password options.
>
> > >> TJG
>
> > > That's exactly my point. I do not want to have to specify username and
> > > password options. For instance, when creating a Windows Service
> > > in .NET, it is possible to specify that the service should run using
> > > the LocalService or NetworkService account. Doing this, you would not
> > > need to specify username and password options. Is there a way to
> > > achieve this in Python?
>
> > Sorry, I misread: I mentally removed the "not" in your 'I do not want
> > this service to run under a user account' and reinserted it
> > further on!
>
> > By default, the service will run as LocalSystem: you
> > only specify a username to override that default. The value
> > in Username is passed straight through to the CreateService
> > Win32 API, and the docs for that:
>
> > ?http://msdn.microsoft.com/en-us/library/ms682450%28VS.85%29.aspx
>
> > say:
>
> > """
> > lpServiceStartName [in, optional]
>
> > ? ? The name of the account under which the service should run. If the service type is SERVICE_WIN32_OWN_PROCESS, use an account name in the form DomainName\UserName. The service process will be logged on as this user. If the account belongs to the built-in domain, you can specify .\UserName.
>
> > ? ? If this parameter is NULL, CreateService uses the LocalSystem account. If the service type specifies SERVICE_INTERACTIVE_PROCESS, the service must run in the LocalSystem account.
>
> > ? ? If this parameter is NT AUTHORITY\LocalService, CreateService uses the LocalService account. If the parameter is NT AUTHORITY\NetworkService, CreateService uses the NetworkService account.
>
> > ? ? A shared process can run as any user.
>
> > ? ? If the service type is SERVICE_KERNEL_DRIVER or SERVICE_FILE_SYSTEM_DRIVER, the name is the driver object name that the system uses to load the device driver. Specify NULL if the driver is to use a default object name created by the I/O system.
>
> > ? ? A service can be configured to use a managed account or a virtual account. If the service is configured to use a managed service account, the name is the managed service account name. If the service is configured to use a virtual account, specify the name as NT SERVICE\ServiceName. For more information about managed service accounts and virtual accounts, see the Service Accounts Step-by-Step Guide.
>
> > ? ? ? ? Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP/2000: ?Managed service accounts and virtual accounts are not supported until Windows 7 and Windows Server 2008 R2.
> > """
>
> > So, although I haven't tried it, it looks as though you can pass
> > "LocalService" or "NetworkService" and so on if you want to
> > override the default LocalSystem but don't want to specify a
> > username/password.
>
> > TJG
>
> I'll try this stuff. Thanks a million...I'll let everyone know how it
> goes.

I'm finding it hard to install my Python service. When I try to
install the service, this is what I get:

Error Installing Service: Access is Denied. (5)

Event with a correct username and password (I think).
Also, inheriting from the win32serviceutil.Framework class, I do not
see a way to explicitly specify the serviceType. I know some of the
parameters such as the startupType can be specified when installing
the service in the command line, but how are these things specified in
the service code when inheriting from win32serviceutil.Framework
(especially the serviceType).

Does this mean I would have to code my service from scratch without
using win32serviceutil.Framework? Basically, I still can't install my
service using a NetworkService or LocalSystem Account because it still
requires me to specify a username and password. Following Tim Golden's
advice, I'm trying to specify the service type in order to determine
what account to run the service under. Please help!


From hendrik at microcorp.co.za  Tue Jul 21 04:03:46 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Tue, 21 Jul 2009 10:03:46 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
Message-ID: <200907211003.46253.hendrik@microcorp.co.za>

On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> > The main reason why you need both lists and tuples is that because a
> > tuple of immutable objects is itself immutable you can use it as a
> > dictionary key.
>
> Really? That sounds interesting, although I can't think of any real-
> world cases where you'd use something like that.

simplest is something like a point in the cartesian plane with
an associated attribute like colour.

- Hendrik




From wilk at flibuste.net  Tue Jul 21 04:19:29 2009
From: wilk at flibuste.net (William Dode)
Date: 21 Jul 2009 08:19:29 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
Message-ID: <4a657a11$0$417$426a74cc@news.free.fr>

On 20-07-2009, srepmub wrote:
>
>> Nice timings, can you please show me the Python, Java and C code
>> versions? I may do more tests.

Of course, the codes are here :

http://hg.flibuste.net/libre/games/cheval

Like you'll see, i tried to use exactly the same code for each langage.

>
> also, which shedskin options did you use? did you use -bw, to disable
> bounds and wrap-around checking? this can make quite a difference for
> code that does a lot of indexing. if the code uses random numbers,
> then -r can also make a big difference, to use C rand(), instead of
> Python compatible random numbers.
>
> and which C++ compiler flags did you use? the default -O2, or
> something like -O3 -fomit-frame-pointer -msse2..?

I used the default, shedksin cheval.py; make
shedskin 0.2

With -bw and -O3 -fomit-frame-pointer -msse2 i have 5.5s (instead of 8)

Let me know if you find better.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From wilk at flibuste.net  Tue Jul 21 04:20:29 2009
From: wilk at flibuste.net (William Dode)
Date: 21 Jul 2009 08:20:29 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<mailman.3437.1248114427.8015.python-list@python.org>
	<04f03d96-46b7-4761-8498-9149f19ecba6@k6g2000yqn.googlegroups.com>
Message-ID: <4a657a4d$0$417$426a74cc@news.free.fr>

On 20-07-2009, Bearophile wrote:
> Skip Montanaro:
>> I read just enough French to know that "avec" means "with", but I don't
>> understand the difference between "avec malloc *int" and "avec []". ?Can you
>> explain please?
>
> Maybe it's the time difference between using a Python list from Cython
> and using a C "array" allocated with a malloc from Cython.

yes, it's this

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From ben+python at benfinney.id.au  Tue Jul 21 04:36:14 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 21 Jul 2009 18:36:14 +1000
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<47ab4ab6-d8c8-4997-8963-ac41b00dd10f@y10g2000prg.googlegroups.com>
Message-ID: <87ws628mbl.fsf@benfinney.id.au>

John Machin <sjmachin at lexicon.net> writes:

> OK, I'll bite: where does the Python 3.x bytearray type

I wasn't previously aware of it, thanks for bringing it to my attention
<URL:http://docs.python.org/3.1/library/stdtypes.html#bytes-methods>.

> fit into your taxonomy? At first glance it appears to be mutable and
> have a fair swag of functionality.

Yes. I'd classify it as a mutable array of bytes :-) but, as such, not
to be used as a text string.

-- 
 \                ?Science doesn't work by vote and it doesn't work by |
  `\        authority.? ?Richard Dawkins, _Big Mistake_ (The Guardian, |
_o__)                                                      2006-12-27) |
Ben Finney


From ben+python at benfinney.id.au  Tue Jul 21 04:38:31 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 21 Jul 2009 18:38:31 +1000
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <87skgq8m7s.fsf@benfinney.id.au>

Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:

> On Mon, 20 Jul 2009 21:08:22 +1000, Ben Finney wrote:
> > A mutable string would not (AFAICT) be usefully implementable as a
> > subclass of the built-in string types. So even if such a type
> > existed, it would not be useable with all the functionality that
> > works with strings.
> 
> If applications ignore duck-typing and do isinstance(value, str), it's
> arguably the application and not the value that is broken.

Agreed, I wouldn't advise that. My point was rather meant to imply that
subclassing the built-in (immutable) string types was the best way to
usefully get all their functionality, rather than re-implementing most
of it.

-- 
 \     ?I went to a restaurant that serves ?breakfast at any time?. So |
  `\    I ordered French Toast during the Renaissance.? ?Steven Wright |
_o__)                                                                  |
Ben Finney


From dickinsm at gmail.com  Tue Jul 21 04:51:50 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Tue, 21 Jul 2009 01:51:50 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <24485116.post@talk.nabble.com>
	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au> 
	<4A5DE5E7.5070003@mrabarnett.plus.com> <24543805.post@talk.nabble.com> 
	<mailman.3454.1248143502.8015.python-list@python.org>
Message-ID: <8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>

On Jul 20, 11:34?pm, Ethan Furman <et... at stoneleaf.us> wrote:
> Dr. Phillip M. Feldman wrote:
> ?> Suppose that 'xor' returns the value that is true when only one value is
> ?> true, and False otherwise. ?This definition of xor doesn't have the
> standard
> ?> associative property, that is,
> ?>
> ?> (a xor b) xor c
> ?>
> ?> will not necessarily equal
> ?>
> ?> a xor (b xor c)
> ?>
> ?> To see that this is the case, let a= 1, b= 2, and c= 3.
> ?>
> ?> (a xor b) xor c
> ?>
> ?> yields 3, while
> ?>
> ?> a xor (b xor c)
> ?>
> ?> yields 1. ?So, I'd prefer an xor operator that simply returns True or
> False.
> ?>
> ?> Phillip
> ?>
>
> You are, of course, free to write your version however it makes sense to
> you and your team. ?:)
>
> Since the 'and' and 'or' already return objects (and objects evaluate to
> true or false), then 'xor' should behave likewise, IMO. ?I expect that
> would be the case if it were ever added to the language.

I'm not so sure.  Did you ever wonder why the any() and all()
functions introduced in 2.5 return a boolean rather than returning
one of their arguments?  (I did, and I'm still not sure what the
answer is.)

Mark


From juanjose.garciaripoll at googlemail.com  Tue Jul 21 05:23:59 2009
From: juanjose.garciaripoll at googlemail.com (Juanjo)
Date: Tue, 21 Jul 2009 02:23:59 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
	<61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>
Message-ID: <56721e57-e0b4-4d7d-8693-a96d1dca061b@j32g2000yqh.googlegroups.com>

On Jul 21, 6:57?am, Frank Buss <fb at frank-buss.de> wrote:
> Scott Burson wrote:
> > Have you looked atECL?
>
> >http://ecls.sourceforge.net/
>
> > I've used it only a little, so I can't vouch for its stability, but it
> > fits the threading and license requirements (well, some corporate
> > lawyers have trouble with the LGPL, but I think it's usable).
>
> I didn't tried it myself, but looks like it is not very stable:
>
> http://www.mail-archive.com/application-builder at lispniks.com/msg01069...

ECL suffers from fast development problems if this is what you mean.
People are advised to stay with certain releases and we announce when
some ports are broken due to progress along certain lines.

For instance, if I find that the generational garbage collector is
needed for Linux, FreeBSD, OpenBSD and OS X, and it works, I do not
mind dropping temporarily the mingw port until the garbage collector
library catches up. People who wanted to stay with mingw produced a
branch (see Samium's posts) with the old garbage collector.

Now this is not so dramatic. ECL now has a release cycle of ONE MONTH.
If you find that this month's release does not work on your platform
(and this is normally explicit in the announcement), then do not
upgrade and wait one or two months until the problem is solved.

OTOH, people only seem to notice problems when their petty platform is
temporarily broken, but nobody seems to notice the overall stability
and portability of the platform. See the list http://ecls.sourceforge.net/logs.html
which will soon expand including Solaris and regular builds on Windows
using the free Microsoft compiler. And once the ARM computer I have
been gifted by a happy arrives, then Debian-ARM as well.

Juanjo


From milanj at gmail.com  Tue Jul 21 05:37:27 2009
From: milanj at gmail.com (milanj)
Date: Tue, 21 Jul 2009 02:37:27 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>

On Jul 19, 8:31?pm, Frank Buss <f... at frank-buss.de> wrote:
> Python is not that bad. Unlike Lisp, there is much less undefined behavior,
> there is one free unique implementation on the 3 major platforms Linux,
> Windows and MacOS X, which is stable, support multithreading and has a
> default GUI library binding, which is difficult to find for Lisp (e.g. I
> don't know of a free modern and stable Lisp implemenation with
> mulithreading support for Windows, with a licence with which you can use it
> in closed source commercial programs, like you can do with Python). Many
> problems in the Lispbuilder mailing list are related to problems due to
> different operating systems and Lisp implementations.

> Frank Buss, f... at frank-buss.dehttp://www.frank-buss.de,http://www.it4-systems.de

Someone should mention Clozure CL - http://trac.clozure.com/openmcl
As you can see there is os x, freebsd, linux, solaris and windows port
and all of them use native threads (python still use green threads ?)
and development is pretty alive, they did planty of developing last
year[s], ccl licence permits you to deliver closed source programs ...
CCL is promising bright feature to CL since looks like the insist of
building stable implementation across most arch in use today




From martin.hellwig at dcuktec.org  Tue Jul 21 05:40:54 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 21 Jul 2009 10:40:54 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>
Message-ID: <fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>

sightseer wrote:
<knip>
> 
> Error Installing Service: Access is Denied. (5)
> 
<knip>
Are you trying to do this on windows vista?

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 05:56:33 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 06:56:33 -0300
Subject: ignore special characters in python regex
References: <4A654C01.2000508@al.com.au>
Message-ID: <op.uxewkjaxx6zn5v@gabriel.cpe.telecentro.net.ar>

En Tue, 21 Jul 2009 02:02:57 -0300, Astan Chee <astan.chee at al.com.au>  
escribi?:

> I'm reading text from a file (per line) and I want to do a regex using  
> these lines but I want the regex to ignore any special characters and  
> treat them like normal strings.
> Is there a regex function that can do this?
> Here is what I have so far:
> fp = open('file.txt','r')
> notes = fp.readlines()
> fp.close()
> strin = "this is what I want"
> for note in notes:
>      if re.search(r""+ str(note) + "",strin):
>            print "Found " + str(note) + " in " + strin

You don't even need a regex for that.

py> "fragil" in "supercalifragilisticexpialidocious"
True

Note that: r""+ str(note) + ""
is the same as: str(note)
which in turn is the same as: note

Remember that each line keeps its '\n' final!

for note in notes:
   if note.rstrip('\n') in strin:
     print "Found %s in %s" % (note, strin)

-- 
Gabriel Genellina



From duncan.booth at invalid.invalid  Tue Jul 21 06:28:16 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 21 Jul 2009 10:28:16 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1> <m2fxcrnj5e.fsf@cs.uu.nl>
	<mailman.3441.1248125420.8015.python-list@python.org>
	<87hbx7yp16.fsf@busola.homelinux.net>
Message-ID: <Xns9C4F73A584B79duncanbooth@127.0.0.1>

Hrvoje Niksic <hniksic at xemacs.org> wrote:

> Chris Rebert <clp2 at rebertia.com> writes:
> 
>>>>>>>> x = [2,1,3]
>>>>>>>> print sorted(x)[0]
>>>>DB> 3
>>>
>>> What kind of Python produces that?
>>
>> Assuming you're referring to the latter example, it was added in
>> version 2.4 If you meant the former example, I think that's purely
>> pseudo-Python. 
> 
> sorted([2, 1, 3])[0] evaluates to 1, not 3.
> 

I guess you can tell I broke my unbreakable rule to never post untested 
code without labelling it as such. :-)

-- 
Duncan Booth http://kupuguy.blogspot.com


From jeanmichel at sequans.com  Tue Jul 21 06:36:14 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 21 Jul 2009 12:36:14 +0200
Subject: How to import pydoc and then use it?
In-Reply-To: <1248126024.9281.3.camel@centar>
References: <ea3dd3f8-7145-414a-a14f-610f19b55402@v20g2000yqm.googlegroups.com>
	<1248126024.9281.3.camel@centar>
Message-ID: <4A659A1E.9090509@sequans.com>

Albert Hopkins wrote:
> On Mon, 2009-07-20 at 13:38 -0700, mrstevegross wrote:
>   
>> I know how to use pydoc from the command line. However, because of
>> complicated environmental setup, it would be preferable to run it
>> within a python script as a native API call. That is, my python runner
>> looks a bit like this:
>>
>>   import pydoc
>>   pydoc.generate_html_docs_for(someFile)
>>
>> However, it's not clear to me from the pydoc documentation which
>> function calls I need to use to make this behavior work. Any ideas?
>>     
>
> Did you try 'pydoc pydoc'? ;)
>
>   
>>>> import pydoc
>>>> htmldoc = pydoc.HTMLDoc()
>>>> htmldoc_for_pydoc = htmldoc(pydoc)
>>>> print htmldoc_for_pydoc
>>>>         
>
>   
By the way, just in case the OP didn't know, there is the epydoc module 
(google it) which is doing basically the same things than pydoc, but 
with a much better look and feel to my opinion.

JM


From mark.dufour at gmail.com  Tue Jul 21 08:25:01 2009
From: mark.dufour at gmail.com (srepmub)
Date: Tue, 21 Jul 2009 05:25:01 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
Message-ID: <60222088-2059-49b1-a442-a56fc85d6838@g31g2000yqc.googlegroups.com>


> With -bw and -O3 -fomit-frame-pointer -msse2 i have 5.5s (instead of 8)
>
> Let me know if you find better.

thanks. now I'm wondering how fast does the C version become with
these flags..? :-)


mark.


From nick at craig-wood.com  Tue Jul 21 08:29:58 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Tue, 21 Jul 2009 07:29:58 -0500
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
Message-ID: <slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>

Mark Dufour <mark.dufour at gmail.com> wrote:
>  I have just released version 0.2 of Shed Skin, an experimental
>  (restricted) Python-to-C++ compiler (http://shedskin.googlecode.com).
>  It comes with 7 new example programs (for a total of 40 example
>  programs, at over 12,000 lines) and several important improvements/bug
>  fixes. See http://code.google.com/p/shedskin/wiki/ReleaseNotes for the
>  full changelog.

Cool!

I tried it on a program I wrote to solve a puzzle (Rush Hour).
(Actually it solves the meta-puzzle - trying to make the hardest
possible Rush Hour puzzle.)

After a bit of twiddling (remove psyco and profiling) I got it to
start compiling, but unfortunately it compiled for about an hour (in
iterative type analysis..) used up 600 MB of RAM printing an '*' every
10 minutes or so then gave an error message and gave up.

Unfortunately I shut the window by accident, but the error message was
something about not being able to resolve types I think with a list of
20 or so unresolved types.

Can you give a hint as to how I debug this?  I presume my program has
some instances of non static types which is causing the problem, but
it is going to be a very long debugging session if it takes me an hour
each cycle ;-)

The program is about 700 lines of python (excluding comments).

Thanks

Nick
-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From wilk at flibuste.net  Tue Jul 21 08:44:30 2009
From: wilk at flibuste.net (William Dode)
Date: 21 Jul 2009 12:44:30 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<60222088-2059-49b1-a442-a56fc85d6838@g31g2000yqc.googlegroups.com>
Message-ID: <4a65b82e$0$11946$426a74cc@news.free.fr>

On 21-07-2009, srepmub wrote:
>
>> With -bw and -O3 -fomit-frame-pointer -msse2 i have 5.5s (instead of 8)
>>
>> Let me know if you find better.
>
> thanks. now I'm wondering how fast does the C version become with
> these flags..? :-)

I don't see any difference...

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From dtgeadamo at yahoo.com  Tue Jul 21 08:49:45 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Tue, 21 Jul 2009 05:49:45 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com> 
	<fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>
Message-ID: <3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>

On Jul 21, 10:40?am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
wrote:
> sightseer wrote:
>
> <knip>
>
> > Error Installing Service: Access is Denied. (5)
>
> <knip>
> Are you trying to do this on windows vista?
>
> --
> MPHhttp://blog.dcuktec.com
> 'If consumed, best digested with added seasoning to own preference.'

Yeah, I was trying to do it on Vista. Someone has just helped me out.
I had to deactivate User Account Control on Windows Vista...and now
everything is rosy. Thanks guys.


From craig1.boyd at citi.com  Tue Jul 21 08:52:19 2009
From: craig1.boyd at citi.com (Boyd, Craig1 )
Date: Tue, 21 Jul 2009 07:52:19 -0500
Subject: Auto-generate GUI from a database table structure
In-Reply-To: <op.uxdyhcvlx6zn5v@lepton.softlabbsas.com.ar>
References: <55660F9659966544BBA3AE14CE5D278D01243B8E04@exgtmb08.nam.nsroot.net>
	<op.uxdyhcvlx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <55660F9659966544BBA3AE14CE5D278D01243B8E11@exgtmb08.nam.nsroot.net>

Gabriel,

Thanks for pointing this out.  It does not look like it supports Oracle at this time, which is one of my requirements, but that is based on doing a quick read of the wiki.  I will dig in further and see.  Perhaps it supports ODBC which would be an acceptable work-around. 

Thanks again,
 
Craig

-----Original Message-----
From: python-list-bounces+craig1.boyd=citi.com at python.org [mailto:python-list-bounces+craig1.boyd=citi.com at python.org] On Behalf Of Gabriel Genellina
Sent: Monday, July 20, 2009 4:40 PM
To: python-list at python.org
Subject: Re: Auto-generate GUI from a database table structure

En Mon, 20 Jul 2009 12:09:47 -0300, Boyd, Craig1  <craig1.boyd at citi.com>
escribi?:

> I am trying to write a couple screens to update three or four database 
> tables on Oracle 10g and I was wondering if there was a way to 
> automatically generate some kind of GUI shell based on the tables that 
> I could then fill in with the logic / functionality I need.

I've never actually used it, but the DABO project seems to provide what you want: http://dabodev.com/

--
Gabriel Genellina

--
http://mail.python.org/mailman/listinfo/python-list


From paul at boddie.org.uk  Tue Jul 21 08:55:12 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Tue, 21 Jul 2009 05:55:12 -0700 (PDT)
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application 
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org> 
	<h424b1$gj1$1@panix3.panix.com>
Message-ID: <1c994086-8c58-488f-b3b3-6161c4b2ba05@k30g2000yqf.googlegroups.com>

On 20 Jul, 18:00, a... at pythoncraft.com (Aahz) wrote:
>
> Out of curiosity, are there any JavaScript toolkits that generate code
> that degrades gracefully when JavaScript is disabled?

You mean "Web toolkits which use JavaScript", I presume. I have
written (and use myself) a toolkit/framework called XSLForms (part of
the XSLTools distribution) which supports in-page updates (AJAX,
effectively) that degrade to vanilla whole-page requests if JavaScript
is switched off:

http://www.boddie.org.uk/python/XSLTools.html

I've been meaning to have a few example applications running on that
site to illustrate the point. Some people complain that by
constraining the JavaScript functionality to merely enhance vanilla
HTML/HTTP functionality, one is not using the full potential of the
medium, but having used sites whose JavaScript has failed, thus
preventing the use of those sites almost completely, I think that
stacking AJAX-like stuff on top of normal stuff helps the majority of
developers offer an accessible solution.

Paul


From rashidsdpk at gmail.com  Tue Jul 21 08:56:21 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Tue, 21 Jul 2009 05:56:21 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <2ea811b0-8135-4df2-b3c1-964414291341@g31g2000yqc.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.more link http://0nanotechnology0.blogspot.com/


From c.c.wood at gmail.com  Tue Jul 21 09:22:30 2009
From: c.c.wood at gmail.com (ChrisW)
Date: Tue, 21 Jul 2009 06:22:30 -0700 (PDT)
Subject: Multiple versions of python
Message-ID: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>

Hi,

I have installed 2 versions of python on my Windows XP computer - I
originally had 3.0.1, but then found that the MySQL module only
supported 2.*, so I've now installed that.  I have found that if I
change the Windows Environment Variable path, then I can change the
version of python called when I type 'python' into a command line.
However, I'd like to be able to choose which version I use.  I know
that if I change C:\Python26\python.exe to
C:\Python26\python2.exe and C:\Python30\python.exe to C:
\Python26\python3.exe, then typing 'python2' or 'python3' will invoke
the correct interpreter.  However, is it safe just to rename the
executable files? Is there a more elegant way to achieve the same
task?

Thanks,
Chris


From peter.fodrek at stuba.sk  Tue Jul 21 09:30:47 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Tue, 21 Jul 2009 15:30:47 +0200
Subject: Regular expression
Message-ID: <200907211530.47704.peter.fodrek@stuba.sk>

Dear conference!

I have  third party regular expression

 self.pattern_main = re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
\#\d+\=(?:[+])?\d*(?:\.\d*)?)')

with code

 def readline(self):
        self.line = self.file_in.readline().rstrip()  
	if (len(self.line)) : return True
        else : return False

 while (self.readline()):
            words = self.pattern_main.findall(self.line)


This handles text file  like

// remark
PL_OFF
PARK
FS
MA  52.8806 ,  18.0914
SS
AD_W
PL_ON
C   52.3955 ,  -16.1511 ,  -90.0000

It handles file correctly with two exceptions

1) omits ',' in the a output
2) omits minus sign in the numbers...

Would anyone recommend me what to change regular expression to add thesee two 
think to the output,please?

Thank you for any help.

I  look forward hearing form you
Yours faithfully

Peter Fodrek
 


From Scott.Daniels at Acm.Org  Tue Jul 21 09:46:12 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 21 Jul 2009 06:46:12 -0700
Subject: Mechanize not recognized by py2exe
In-Reply-To: <mailman.3455.1248150809.8015.python-list@python.org>
References: <4A60C81F.7080707@comcast.net>	<op.uxcv11b1x6zn5v@lepton.softlabbsas.com.ar>
	<mailman.3455.1248150809.8015.python-list@python.org>
Message-ID: <J56dnYTMw8lJWfjXnZ2dnUVZ_qydnZ2d@pdx.net>

OrcaSoul wrote:
> ...it's too late to name my first born after you, but
> I did have a cat named Gabriel - she was a great cat!

Remember Gabriel in English uses a hard A, as in the horn
player, not Gabrielle.  I know because when I first read
his posts I made the same trick in my head, and hence
imagined a woman.  I suspect it would come to irk one
almost enough to become a Gabe.

--Scott David Daniels
Scott.Daniels at Acm.Org


From inky788 at gmail.com  Tue Jul 21 09:49:59 2009
From: inky788 at gmail.com (Inky 788)
Date: Tue, 21 Jul 2009 06:49:59 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> [snip] We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.

My guess is that it was probably for optimization reasons long ago.
I've never heard a *good* reason why Python needs both.


From Scott.Daniels at Acm.Org  Tue Jul 21 10:03:29 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 21 Jul 2009 07:03:29 -0700
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <02746e73$0$5185$c3e8da3@news.astraweb.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <MJ6dnXF-O-R9VfjXnZ2dnUVZ_gidnZ2d@pdx.net>

Steven D'Aprano wrote:
> On Mon, 20 Jul 2009 21:08:22 +1000, Ben Finney wrote:
>> What is it you're trying to do that makes you search for a mutable
>> string type? It's likely that a better approach can be found.
> 
> When dealing with very large strings, it is wasteful to have to duplicate 
> the entire string just to mutate a single character.
> 
> However, when dealing with very large strings, it's arguably better to 
> use the rope data structure instead.

The general problem is that whether strings are mutable or not is an
early language design decision, and few languages provide both.
Mutable strings need lots of data copying to be safe passing args to
unknown functions; immutable strings need lots of copying for ncremental
changes.  The rope is a great idea for some cases.

I'd argue Python works better with immutable strings, because Python is
too slow at per-character operations to be running up and down strings
a character at a time, changing here and there.  So it becomes more
natural to deal with strings as chunks to pass around, and it is nice
not to have to copy the strings when doing that passing around.

--Scott David Daniels
Scott.Daniels at Acm.Org


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Tue Jul 21 10:13:00 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Tue, 21 Jul 2009 10:13:00 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
Message-ID: <h44ipk$e7e$1@news.eternal-september.org>

On 2009-07-21 05:37:27 -0400, milanj <milanj at gmail.com> said:

> Someone should mention Clozure CL - http://trac.clozure.com/openmcl
> As you can see there is os x, freebsd, linux, solaris and windows port
> and all of them use native threads (python still use green threads ?)
> and development is pretty alive, they did planty of developing last
> year[s], ccl licence permits you to deliver closed source programs ...
> CCL is promising bright feature to CL since looks like the insist of
> building stable implementation across most arch in use today

Hear, hear!
-- 
Raffael Cavallaro



From Scott.Daniels at Acm.Org  Tue Jul 21 10:17:13 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Tue, 21 Jul 2009 07:17:13 -0700
Subject: Multiple versions of python
In-Reply-To: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
Message-ID: <E_adnRVECZqEUfjXnZ2dnUVZ_qSdnZ2d@pdx.net>

ChrisW wrote:
> Hi,
> 
> I have installed 2 versions of python on my Windows XP computer - I
> originally had 3.0.1, but then found that the MySQL module only
> supported 2.*, so I've now installed that.  I have found that if I
> change the Windows Environment Variable path, then I can change the
> version of python called when I type 'python' into a command line.
> However, I'd like to be able to choose which version I use.  I know
> that if I change C:\Python26\python.exe to
> C:\Python26\python2.exe and C:\Python30\python.exe to C:
> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
> the correct interpreter.  However, is it safe just to rename the
> executable files? Is there a more elegant way to achieve the same
> task?
I wouldn't rename them.  You can, of course, copy them (so you have two
executables), or you can pick a somedir on your path (I made a directory
"C:\cmds" that I add to my path, but tastes vary).

C:> copy con <somedir>\py25.cmd
C:\Python25\python\python.exe %*
^Z
C:> copy con <somedir>\py31.cmd
C:\Python31\python\python.exe %*
^Z

I'd use the two-digit form, as that is where interface changes
happen; trying code with py24, py25, py26 can be convenient.
By the way, install Python 3.1 rather than 3.0; think of 3.0 as the
alpha of the 3.X branches (it will get no love at all now that 3.1
is out).

--Scott David Daniels
Scott.Daniels at Acm.Org


From davea at dejaviewphoto.com  Tue Jul 21 10:19:42 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Tue, 21 Jul 2009 10:19:42 -0400
Subject: Multiple versions of python
In-Reply-To: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
Message-ID: <4A65CE7E.6090800@dejaviewphoto.com>

ChrisW wrote:
> Hi,
>
> I have installed 2 versions of python on my Windows XP computer - I
> originally had 3.0.1, but then found that the MySQL module only
> supported 2.*, so I've now installed that.  I have found that if I
> change the Windows Environment Variable path, then I can change the
> version of python called when I type 'python' into a command line.
> However, I'd like to be able to choose which version I use.  I know
> that if I change C:\Python26\python.exe to
> C:\Python26\python2.exe and C:\Python30\python.exe to C:
> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
> the correct interpreter.  However, is it safe just to rename the
> executable files? Is there a more elegant way to achieve the same
> task?
>
> Thanks,
> Chris
>
>   
The elegant way is to have a batch directory on your PATH ( I use  
m:\t\bat )  and put your *.bat files there.   I do NOT put any python 
installations on the PATH.

For example, I have a batch file called:     m:\t\bat\python26.bat

c:\progfiles\python26\python.exe %*

The %* syntax means pass all arguments through to the program.

Once it all works, you can add an "@" in front of the c:   in order to 
suppress echoing the command.  At that point, it'll look and work the 
same way as what you did, but without modifying anything in the install 
directory.    (You may want  python26.bat, pythonw26.bat, python31.bat 
and pythonw31.bat)



The other thing you may want to do in a batch file is to change the file 
associations so that you can run the .py file directly, without typing 
"python" or "pythonw" in front of it.

The relevant Windows commands are:     assoc and ftype      And on a 
related note, you may want to edit the PATHEXT environment variable, to 
add .PY and .PYW




From hv at tbz-pariv.de  Tue Jul 21 10:27:27 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Tue, 21 Jul 2009 16:27:27 +0200
Subject: Workflow Libraries (DB vs Code)
Message-ID: <7cm1ifF28jmnhU1@mid.individual.net>

Hi,

I need to write some simple workflows with web interface.

For the web stuff I will use django, but I am not sure how
to do the workflow part.

Here are ideas:

Do it myself. I don't think it will be difficult, I did things like
this before. But they were not reusable.

Use spiff Workflow library http://code.google.com/p/spiff-workflow/

Use goflow for django (port of OpenFlow of Zope). It does not look like a active project.

Has anyone worked with spiff, goflow or other workflow software? What do you like and
dislike?

Somehow I like it the way goflow does it: The process definitions are stored
in the database. But on the other hand I prefer to have things like this in
a SVN-Repository.

Creating the workflow definitions will be done by python programmers. I don't need
a GUI to build them.

There are many languages to define processes (BPML, XPDL, BPEL or YAWL). But I prefer python.

Feedback welcome,

  Thomas

-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From sajmikins at gmail.com  Tue Jul 21 10:30:56 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 07:30:56 -0700 (PDT)
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com> 
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
Message-ID: <b648f2ba-f589-4c4a-a729-5c9c4551603c@s31g2000yqs.googlegroups.com>

On Jul 20, 3:29?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac <alan.is... at gmail.com> ?
> escribi?:
>
> >> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
> >>> def apply2(itr, methodname, *args, **kwargs):
> >>> ? ? f = operator.methodcaller(methodname, *args, **kwargs)
> >>> ? ? for item in itr:
> >>> ? ? ? ? f(item)
>
> > On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
> >> for obj in objects:
> >> ? ? getattr(obj, methodname)(*args, **kwargs)
>
> > Are there any obvious considerations in choosing
> > between those two?
>
> The operator.methodcaller version is faster in my tests for large ?
> collections, but slightly slower when you have very few elements.
>
> <code>
> import operator
> import timeit
>
> class X:
> ? ?def method(self, x, y, **kw): pass
>
> def apply1(itr, methodname, *args, **kwargs):
> ? ? ?for item in itr:
> ? ? ? ? ?getattr(item, methodname)(*args, **kwargs)
>
> def apply2(itr, methodname, *args, **kwargs):
> ? ? ?f = operator.methodcaller(methodname, *args, **kwargs)
> ? ? ?for item in itr:
> ? ? ? ? ?f(item)
>
> L=[X() for _ in range(3000)]
> apply1(L,'method', 1, 2, foo=3)
> apply2(L,'method', 1, 2, foo=3)
>
> timeit.timeit(setup="from __main__ import apply1,apply2,L", ?
> stmt="apply1(L,'method', 1, 2, foo=3)", number=1000)
> timeit.timeit(setup="from __main__ import apply1,apply2,L", ?
> stmt="apply2(L,'method', 1, 2, foo=3)", number=1000)
> </code>
>
> --
> Gabriel Genellina

If your instances are all of the same class you can pass in the method
directly like so:

def apply3(iterator, method, *args, **kwargs):
    for item in iterator:
        method(item, *args, **kwargs)

class X:
   def method(self, x, y, **kw): pass

items = [X() for _ in range(10)]

apply3(items, X.method, 1, 2, foo=3)

HTH,
~Simon


From sajmikins at gmail.com  Tue Jul 21 10:42:08 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 10:42:08 -0400
Subject: tough-to-explain Python
In-Reply-To: <7xws627qc1.fsf@ruckus.brouhaha.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7xljmk8q1m.fsf@ruckus.brouhaha.com>
	<6348dcb8-bfc1-446e-b7bf-28657e2b607e@j32g2000yqh.googlegroups.com>
	<7xws627qc1.fsf@ruckus.brouhaha.com>
Message-ID: <50f98a4c0907210742q47aa3e21s9a410e833ab78718@mail.gmail.com>

On Mon, Jul 20, 2009 at 9:54 PM, Paul Rubin<http://phr.cx at nospam.invalid> wrote:
> Simon Forman <sajmikins at gmail.com> writes:
>> But I'm glad it's there to study, these are wheels I don't have to
>> invent for myself.
>
> http://dwheeler.com/essays/high-assurance-floss.html
>
> might be an interesting place to start.

OO la la!  Thank you!


From slobodan.blazeski at gmail.com  Tue Jul 21 10:42:18 2009
From: slobodan.blazeski at gmail.com (Slobodan Blazeski)
Date: Tue, 21 Jul 2009 07:42:18 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <03fef26b-b8ed-4863-ba55-309624c97eff@o6g2000yqj.googlegroups.com>

On Jul 19, 7:33?pm, fft1976 <fft1... at gmail.com> wrote:
> On Jul 19, 9:55?am, Frank Buss <f... at frank-buss.de> wrote:
>
> > E.g. the number system: In many Lisp
> > implementations (/ 2 3) results in the fractional object 2/3. In Python 2.6
> > "2 / 3" results in "0". Looks like with Python 3.1 they have fixed it, now
> > it returns "0.6666666666", which will result in lots of fun for porting
> > applications written for Python <= 2.6.
>
> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

Worse is better?

Bobi
http://www.linkedin.com/in/slobodanblazeski


From bearophileHUGS at lycos.com  Tue Jul 21 10:46:26 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 21 Jul 2009 07:46:26 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
Message-ID: <ada772ff-f8b6-4442-84f8-15ef663ac200@26g2000yqk.googlegroups.com>

Nick Craig-Wood:
> Can you give a hint as to how I debug this? ?I presume my program has
> some instances of non static types which is causing the problem, but
> it is going to be a very long debugging session if it takes me an hour
> each cycle ;-)
>
> The program is about 700 lines of python (excluding comments).

You can show us the Python (SSPython) code, and we can try to find the
problem. Sometimes there's no simple ways to solve such problems.

Generally for not very large progrograms if SS doesn't compile in
about a minute or so then it's gone in infinite loop (there's a
compilation flag that avoids some infinite loops, try it).

Bye,
bearophile


From python at mrabarnett.plus.com  Tue Jul 21 10:50:15 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 21 Jul 2009 15:50:15 +0100
Subject: Regular expression
In-Reply-To: <200907211530.47704.peter.fodrek@stuba.sk>
References: <200907211530.47704.peter.fodrek@stuba.sk>
Message-ID: <4A65D5A7.9060908@mrabarnett.plus.com>

Peter Fodrek wrote:
> Dear conference!
> 
> I have  third party regular expression
> 
>  self.pattern_main = re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')
> 
[snip]
> It handles file correctly with two exceptions
> 
> 1) omits ',' in the a output
> 2) omits minus sign in the numbers...
> 
> Would anyone recommend me what to change regular expression to add thesee two 
> think to the output,please?
> 

self.pattern_main = 
re.compile(r'(\s+|,|-?\w\+?\d*(?:\.\d*)?|\w#\d+|\(.*?\)|#\d+=\+?\d*(?:\.\d*)?)')


From piet at cs.uu.nl  Tue Jul 21 11:05:36 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 17:05:36 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
	<mailman.3460.1248163342.8015.python-list@python.org>
Message-ID: <m2r5wam5z3.fsf@cs.uu.nl>

>>>>> Hendrik van Rooyen <hendrik at microcorp.co.za> (HvR) wrote:

>HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>> On Jul 20, 6:08?pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>>> > The main reason why you need both lists and tuples is that because a
>>> > tuple of immutable objects is itself immutable you can use it as a
>>> > dictionary key.
>>> 
>>> Really? That sounds interesting, although I can't think of any real-
>>> world cases where you'd use something like that.

>HvR> simplest is something like a point in the cartesian plane with
>HvR> an associated attribute like colour.

There are numerous other examples. Anytime you need a key that is not a
single object but composed of more than one:
Name + birthday
Street + number + City
Student + Course
etc.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From bearophileHUGS at lycos.com  Tue Jul 21 11:08:37 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 21 Jul 2009 08:08:37 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
Message-ID: <4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>

William Dode':
> http://hg.flibuste.net/libre/games/cheval
> Like you'll see, i tried to use exactly the same code for each langage.

It's a cute solver.

Few more versions of mine:

#1, a Psyco version of mine:
http://codepad.org/9m5rf7kX

#2, unrolled Psyco version:
http://codepad.org/gKFLu34M

#3, a quick D (D1) version:
http://codepad.org/Tk9FL7Xk

Timings (no printing), seconds, best of 3:
#1: 4.79
#2: 3.67
#3: 1.10
Your Psyco version: 13.37
Your C version, compiled with GCC 4.3.2, -s -O3 -fomit-frame-pointer:
3.79

I have timed the whole running time of the programs, with an external
timer, so my timings include the start of the PythonVM and the final
cleanup of the GC.

Please, feel free to time my code again, so we can compare with your
other timings (Java, etc) better.

I have used Psyco 1.6 final and Python 2.6.2 on a Core2 CPU at 2 GHz.

To compile the D1 code you can use the free DMD compiler for D1, I
have used version 1.042, www.digitalmars.com/d/download.html ).

In such benchmarks it's often better to start from the fastest low
level code (written in an imperative language as C/D/C++, or a version
in a functional language like Clean or OCaML) and then use it to
create higher level versions (in Python, etc). This offers you a
baseline timing, and usually the small differences of the higher level
code compared to the original C/Clean code don't invalidate the test.

I have changed only small things in the program, as you can see the
Psyco program #2 is faster than your C code :-) If you learn how to
use it well, Psyco1.6 can often lead to very good performance. But lot
of people don't know how to use Psyco well (I too am ignorant: I don't
know how to profile Python programs yet).

Bye,
bearophile


From dns4 at cornell.edu  Tue Jul 21 11:14:37 2009
From: dns4 at cornell.edu (David Smith)
Date: Tue, 21 Jul 2009 11:14:37 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <m2r5wam5z3.fsf@cs.uu.nl>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
	<mailman.3460.1248163342.8015.python-list@python.org>
	<m2r5wam5z3.fsf@cs.uu.nl>
Message-ID: <h44m12$hql$1@ruby.cit.cornell.edu>

Piet van Oostrum wrote:
>>>>>> Hendrik van Rooyen <hendrik at microcorp.co.za> (HvR) wrote:
> 
>> HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>>> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>>>>> The main reason why you need both lists and tuples is that because a
>>>>> tuple of immutable objects is itself immutable you can use it as a
>>>>> dictionary key.
>>>> Really? That sounds interesting, although I can't think of any real-
>>>> world cases where you'd use something like that.
> 
>> HvR> simplest is something like a point in the cartesian plane with
>> HvR> an associated attribute like colour.
> 
> There are numerous other examples. Anytime you need a key that is not a
> single object but composed of more than one:
> Name + birthday
> Street + number + City
> Student + Course
> etc.

Compound keys (like what's listed above) can also be used for sorting
lists of dictionaries using DSU style sorting.  Something I believe (and
 I could be wrong) won't work with mutable types like lists.

--David


From piet at cs.uu.nl  Tue Jul 21 11:32:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 17:32:26 +0200
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<Xns9C4EB8936A361duncanbooth@127.0.0.1>
	<4f467d53-b121-430f-b153-8e4d4fc8476a@o15g2000yqm.googlegroups.com>
	<mailman.3460.1248163342.8015.python-list@python.org>
	<m2r5wam5z3.fsf@cs.uu.nl> <h44m12$hql$1@ruby.cit.cornell.edu>
Message-ID: <m2my6ym4qd.fsf@cs.uu.nl>

>>>>> David Smith <dns4 at cornell.edu> (DS) wrote:

>DS> Piet van Oostrum wrote:
>>>>>>>> Hendrik van Rooyen <hendrik at microcorp.co.za> (HvR) wrote:
>>> 
>HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>>>>> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
>>>>> The main reason why you need both lists and tuples is that because a
>>>>> tuple of immutable objects is itself immutable you can use it as a
>>>>> dictionary key.
>>>>>> Really? That sounds interesting, although I can't think of any real-
>>>>>> world cases where you'd use something like that.
>>> 
>HvR> simplest is something like a point in the cartesian plane with
>HvR> an associated attribute like colour.
>>> 
>>> There are numerous other examples. Anytime you need a key that is not a
>>> single object but composed of more than one:
>>> Name + birthday
>>> Street + number + City
>>> Student + Course
>>> etc.

>DS> Compound keys (like what's listed above) can also be used for sorting
>DS> lists of dictionaries using DSU style sorting.  Something I believe (and
>DS>  I could be wrong) won't work with mutable types like lists.

For sorting there is no problem with mutable arrays as long as you don't
mutate them during the sorting process (for example in the comparison
routine). Doing that would be extremely perverse. And there is no
enforcement of that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From ethan at stoneleaf.us  Tue Jul 21 11:34:19 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Tue, 21 Jul 2009 08:34:19 -0700
Subject: missing 'xor' Boolean operator
In-Reply-To: <8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>
References: <24485116.post@talk.nabble.com>	<pan.2009.07.15.09.11.44@REMOVE.THIS.cybersource.com.au>
	<4A5DE5E7.5070003@mrabarnett.plus.com>
	<24543805.post@talk.nabble.com>
	<mailman.3454.1248143502.8015.python-list@python.org>
	<8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>
Message-ID: <4A65DFFB.3090004@stoneleaf.us>

Mark Dickinson wrote:
> On Jul 20, 11:34 pm, Ethan Furman <et... at stoneleaf.us> wrote:
> 
>>Dr. Phillip M. Feldman wrote:
>> > Suppose that 'xor' returns the value that is true when only one value is
>> > true, and False otherwise.  This definition of xor doesn't have the
>>standard
>> > associative property, that is,
>> >
>> > (a xor b) xor c
>> >
>> > will not necessarily equal
>> >
>> > a xor (b xor c)
>> >
>> > To see that this is the case, let a= 1, b= 2, and c= 3.
>> >
>> > (a xor b) xor c
>> >
>> > yields 3, while
>> >
>> > a xor (b xor c)
>> >
>> > yields 1.  So, I'd prefer an xor operator that simply returns True or
>>False.
>> >
>> > Phillip
>> >
>>
>>You are, of course, free to write your version however it makes sense to
>>you and your team.  :)
>>
>>Since the 'and' and 'or' already return objects (and objects evaluate to
>>true or false), then 'xor' should behave likewise, IMO.  I expect that
>>would be the case if it were ever added to the language.
> 
> 
> I'm not so sure.  Did you ever wonder why the any() and all()
> functions introduced in 2.5 return a boolean rather than returning
> one of their arguments?  (I did, and I'm still not sure what the
> answer is.)
> 
> Mark


Very good question -- I likewise do not know the answer.  I will only 
observe that any() and all() are functions, while 'and' and 'or' are 
not.  If one wanted the object-returning behavior one could string 
together 'or's or 'and's instead.

~Ethan~
--
Thinking out loud here -- YMMV.  :)


From rhodri at wildebst.demon.co.uk  Tue Jul 21 11:39:51 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 21 Jul 2009 16:39:51 +0100
Subject: Regular expression
In-Reply-To: <200907211530.47704.peter.fodrek@stuba.sk>
References: <200907211530.47704.peter.fodrek@stuba.sk>
Message-ID: <op.uxfcgpzua8ncjz@gnudebst>

On Tue, 21 Jul 2009 14:30:47 +0100, Peter Fodrek <peter.fodrek at stuba.sk>  
wrote:

> Dear conference!
>
> I have  third party regular expression
>
>  self.pattern_main =  
> re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')

Always use raw strings (r"...") when you're working with regular
expressions.  *Always*.  It may happen that you don't need them,
as in this case, because Python fails to throw an exception when
it meets unknown escape sequences in string literals, but when
you do need them you will spend hours before realising it.

Also, whoever wrote this regular expression should be taken
out and slapped with a wet fish, for it is abominable and
unlikely to look much like what you actually want.

> with code
>
>  def readline(self):
>         self.line = self.file_in.readline().rstrip()
> 	if (len(self.line)) : return True
>         else : return False
>
>  while (self.readline()):
>             words = self.pattern_main.findall(self.line)

Um.  Yes.  Well.

> This handles text file  like
>
> // remark
> PL_OFF
> PARK
> FS
> MA  52.8806 ,  18.0914
> SS
> AD_W
> PL_ON
> C   52.3955 ,  -16.1511 ,  -90.0000
>
> It handles file correctly with two exceptions
>
> 1) omits ',' in the a output

You don't do any output, so it's hard to correct that!

> 2) omits minus sign in the numbers...
>
> Would anyone recommend me what to change regular expression to add  
> thesee two
> think to the output,please?

It would help considerably if you explained what "it handles file
correctly" means, since the regular expresion makes little sense
with the input you give.  What are you trying to extract from the
input, and what do you think you are getting at the moment?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From c.c.wood at gmail.com  Tue Jul 21 11:51:08 2009
From: c.c.wood at gmail.com (CCW)
Date: Tue, 21 Jul 2009 08:51:08 -0700 (PDT)
Subject: Multiple versions of python
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
	<mailman.3465.1248186000.8015.python-list@python.org>
Message-ID: <98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>

On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
> ChrisW wrote:
> > Hi,
>
> > I have installed 2 versions of python on my Windows XP computer - I
> > originally had 3.0.1, but then found that the MySQL module only
> > supported 2.*, so I've now installed that. ?I have found that if I
> > change the Windows Environment Variable path, then I can change the
> > version of python called when I type 'python' into a command line.
> > However, I'd like to be able to choose which version I use. ?I know
> > that if I change C:\Python26\python.exe to
> > C:\Python26\python2.exe and C:\Python30\python.exe to C:
> > \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
> > the correct interpreter. ?However, is it safe just to rename the
> > executable files? Is there a more elegant way to achieve the same
> > task?
>
> > Thanks,
> > Chris
>
> The elegant way is to have a batch directory on your PATH ( I use ?
> m:\t\bat ) ?and put your *.bat files there. ? I do NOT put any python
> installations on the PATH.
>
> For example, I have a batch file called: ? ? m:\t\bat\python26.bat
>
> c:\progfiles\python26\python.exe %*
>
> The %* syntax means pass all arguments through to the program.
>
> Once it all works, you can add an "@" in front of the c: ? in order to
> suppress echoing the command. ?At that point, it'll look and work the
> same way as what you did, but without modifying anything in the install
> directory. ? ?(You may want ?python26.bat, pythonw26.bat, python31.bat
> and pythonw31.bat)
>
> The other thing you may want to do in a batch file is to change the file
> associations so that you can run the .py file directly, without typing
> "python" or "pythonw" in front of it.
>
> The relevant Windows commands are: ? ? assoc and ftype ? ? ?And on a
> related note, you may want to edit the PATHEXT environment variable, to
> add .PY and .PYW

Thanks for this - this way made a bit more sense to me.  I've now got
C:\commands with the 4 .bat files in, and C:\commands in my path.  It
all seems to work :) I think I've missed the point of the @ though -
it doesn't seem to make any difference..

I'm also a bit confused with the associations - since I've got python
2.6 and 3.1, surely the command I type (python26 or python31) is the
only way to force a script to be run using a specific interpreter at
runtime without having to change the .bat file every time I want to
run a script using 3.1 instead of 2.6?


From peter.fodrek at stuba.sk  Tue Jul 21 11:51:32 2009
From: peter.fodrek at stuba.sk (Peter Fodrek)
Date: Tue, 21 Jul 2009 17:51:32 +0200
Subject: Regular expression
In-Reply-To: <4A65D5A7.9060908@mrabarnett.plus.com>
References: <200907211530.47704.peter.fodrek@stuba.sk>
	<4A65D5A7.9060908@mrabarnett.plus.com>
Message-ID: <86771222-4E27-4E0C-BC56-948169A277BF@stuba.sk>


21.7.2009 v 16:50, MRAB:

> Peter Fodrek wrote:
>> Dear conference!
>> I have  third party regular expression
>> self.pattern_main = re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d 
>> +|\(.*?\)|
>> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')
> [snip]
>> It handles file correctly with two exceptions
>> 1) omits ',' in the a output
>> 2) omits minus sign in the numbers...
>> Would anyone recommend me what to change regular expression to add  
>> thesee two think to the output,please?
>
> self.pattern_main = re.compile(r'(\s+|,|-?\w\+?\d*(?:\.\d*)?|\w#\d+|\ 
> (.*?\)|#\d+=\+?\d*(?:\.\d*)?)')

Thank you I will try yesterday...

Peter 


From deets at nospam.web.de  Tue Jul 21 11:58:47 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 21 Jul 2009 17:58:47 +0200
Subject: Workflow Libraries (DB vs Code)
References: <7cm1ifF28jmnhU1@mid.individual.net>
Message-ID: <7cm6kmF26g9srU1@mid.uni-berlin.de>

Thomas Guettler wrote:

> Hi,
> 
> I need to write some simple workflows with web interface.
> 
> For the web stuff I will use django, but I am not sure how
> to do the workflow part.

Did you consider using OpenERP? It comes with a web-frontend
(TG1.0.8-based), but also offers a XMLRPC-server to connect to, so using it
from within django shouldn't be any difficult.

Workflow-definitions are stored in the DB, and can be generated visually,
not sure if they have to though.

I'm not very familiar with the system myself, but the EuroPython
presentation was truly impressive.

Diez


From piet at cs.uu.nl  Tue Jul 21 11:59:47 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 17:59:47 +0200
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
Message-ID: <m2iqhmm3gs.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> M2Crypto package not showing the 'recipient_public_key.pem' file at
>j> linux terminal .how do i get/connect with recipient public key.

>j> exactly i need to check how can i open this file through linux
>j> commands.

>j> import M2Crypto def encrypt(): recip = M2Crypto.RSA.load_pub_key(open
>j> ('recipient_public_key.pem','rb').read()) print recip; plaintext =
>j> whatever i need to encrypt msg = recip.public_encrypt
>j> (plaintext,RSA.pkcs1_padding) print msg;

>j> after calling the function its not giving any output and even any
>j> error

>j> i also tried as 'Will' said

>j> pk = open('public_key.pem','rb').read() print pk; rsa =
>j> M2Crypto.RSA.load_pub_key(pk)

>j> whats the mistake i am not getting .will somebody help me out.
>j> is something wrong in opening 'recipient_public_key.pem'. is M2Crypto
>j> contain this file inbuilt .from where this file taking public key of
>j> the recipient i'. what this file contain and how it will work .should
>j> i need to create such a file for my purpose.if it is then how can i
>j> create this  and how it will retrieve the key,where i recognize my
>j> recipient to get his public key .is something like database at server.

>j> please give me a quick response......
>j> looking for your answer.

Please:
1. Type your python code with newlines and proper indentation.
2. Show the error messages that your code gives when you run it.
3. Use proper capital letters at the beginning of your sentences.
4. Don't fire so many questions in rapid succession.

The recipient_public_key.pem file is the public key of the recipient
which means the person that is going to receive the encrypted message.
You should get it from the recipient him/herself or from some key store
where s/he has deposited it.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From iwan at reahl.org  Tue Jul 21 12:05:31 2009
From: iwan at reahl.org (Iwan Vosloo)
Date: Tue, 21 Jul 2009 18:05:31 +0200
Subject: Issue combining gzip and subprocess
Message-ID: <1248192331.30167.38.camel@easymoney>

Hi there,

We tried to gzip the output of a shell command, but this results in a
strange error: the resulting file seems to be the concatenation of the
plaintext file with the zipped content.

For example:

f = gzip.open(filename, 'w')
subprocess.check_call(['ls','-la'], stdout=f)
f.close()

Using a normal file works as expected, but a GzipFile results in a file
containing what looks like the unzipped data, followed by the zipped
data.

I suspect this may have something to do with limitations of GzipFile
such as it not implementing truncate().

Does anyone have an explanation / can you suggest a nice solution for
doing what we are trying to do?

Regards
- Iwan



From nad at acm.org  Tue Jul 21 12:08:48 2009
From: nad at acm.org (Ned Deily)
Date: Tue, 21 Jul 2009 09:08:48 -0700
Subject: PIL for OSX 64bit
References: <e0564f03-f736-4d0f-8c50-e1bce0eb55f8@r2g2000yqm.googlegroups.com>
Message-ID: <nad-29B43F.09084821072009@ger.gmane.org>

In article 
<e0564f03-f736-4d0f-8c50-e1bce0eb55f8 at r2g2000yqm.googlegroups.com>,
 moerchendiser2k3 <googler.1.webmaster at spamgourmet.com> wrote:
> I have a problem with Python and the Python Image Library to get it
> work on OSX 64 bit. Maybe anyone can help me? I started Python in 64
> bit mode and called Image.open(...).load() and got:
> 
> ImportError: The _imaging C module is not installed
[...]

It's hard to know what your problem is without more information.  One 
potential stumbling block: PIL has dependencies on other open-source 
libraries, such as libjpeg and freetype.  You'll need to have 64-bit 
versions of them available when building and when running, as well.  
There are a number of ways to do that.  The simplest might be to 
download pre-built frameworks containing those libraries from here:

http://www.kyngchaos.com/software:frameworks

There are also build scripts there for building your own versions from 
scratch.

-- 
 Ned Deily,
 nad at acm.org



From sajmikins at gmail.com  Tue Jul 21 12:10:57 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 09:10:57 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <c46904d7-d8c5-4d64-8d34-11b0aec1969b@s31g2000yqs.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> My colleagues and I have been working with python for around 6 months
> now, and while we love a lot of what python has done for us and what
> it enables us to do some of the decisions behind such certain
> data-types and their related methods baffle us slightly (when compared
> to the decisions made in other, similarly powerful languages).
>
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
>
> Consider the following:
>
> >>> x = [2,1,3]
> >>> x.sort()
> >>> print x
>
> [1, 2, 3]
>
> Now, if the sort operations were unable to affect the original
> structure of the list (as in JavaScript) you'd effectively have a
> tuple which you could add/remove from, and the example above would
> look more like:
>
> >>> x = [2,1,3]
> >>> print x.sort()
> [1, 2, 3]
> >>> print x
>
> [2,1,3]
>
> This make a lot more sense to us, and follows the convention from
> other languages. It would also mean chaining methods to manipulate
> lists would be easier:
>
> >>> x = [2,1,3]
> >>> print x.sort()[0]
> 3

(As others have already pointed out this would print 1, not 3.)

> >>> print x
>
> [2,1,3]
>
> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.

In this case you can use:

>>> x = [2,1,3]
>>> print min(x)
1

(There's also a max() function.)

> We're not looking to start any arguments or religious wars and we're
> not asking that python be changed into something its not. We'd simply
> like to understand the decision behind the lists and tuple structures.
> We feel that in not "getting" the difference between the two types we
> may be missing out on using these data structures to their full
> potential.


One way to think about tuples (as distinct from lists) is as a short-
hand version of Pascal's 'record' type, or C's 'struct' (with the
caveats that the fields are not named, only indexed, and the types of
the fields are implied by use, not explicitly declared.)

(FWIW: http://en.wikipedia.org/wiki/Record_(computer_science) )

Broadly speaking, lists are useful for things like stacks and queues,
and sorting, while tuples are useful for aggregating heterogeneous
data into coherent units, and you can hash them (provided their
contents are also hashable.)

HTH,
~Simon


From stef.mientki at gmail.com  Tue Jul 21 12:13:30 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Tue, 21 Jul 2009 18:13:30 +0200
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <h428fp$8ja$2@adenine.netfront.net>
References: <mailman.3406.1248034495.8015.python-list@python.org>	<h40adj$bv6$1@adenine.netfront.net>	<mailman.3419.1248082444.8015.python-list@python.org>
	<h428fp$8ja$2@adenine.netfront.net>
Message-ID: <4A65E92A.3050608@gmail.com>

hi Marcus,
>>> That sounds like a very specialized type of thing, 
>> Well from an application point of view,
>> with the current netbooks,
>> this looks like a perfect tool for any conversation or meeting.
>>> which only the few people with experience with wxPython, PyAudio, 
>>> and Scintilla could help you with...
>>>
>> I was afraid of that too, so I dropped the question in several places,
>> and the writer of Scintilla himself came with the perfect answer.
>>
>> cheers,Stef
>>> But you might try having a dictionary with notes and associated 
>>> times, or just give each note a four-digit ID number at the 
>>> beginning of it when it's entered and use that in the dictionary (to 
>>> keep keys shorter). Or you could just do a little hack and increase 
>>> the number of bookmarks allowed (seeing as source is available) :p
>>>
>>> Marcus
>>
> Glad you got a good answer from somebody. Sounds like an interesting 
> project. About when would this be headed for a release? Could you post 
> a link to a googlecode or sourceforge project or something so I can 
> follow and/or help with development?
>
For the moment it's just an idea, so no line of code yet.
I first like to tackle all the problems,
at least to the level I think I can handle them.
So first solve the next problem,
before I start coding:
automatic synchronization (file uploading and deleting) between EEE-pc 
and desktop PC over bluetooth.
And another problem, as my customers are physicians,
both the text and audio need to be stored encrypted.

cheers,
Stef
> Marcus



From fb at frank-buss.de  Tue Jul 21 12:44:23 2009
From: fb at frank-buss.de (Frank Buss)
Date: Tue, 21 Jul 2009 18:44:23 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<3f1f6d1c-2fb5-44dc-9caa-dc1f80d39e94@b25g2000prb.googlegroups.com>
	<61cu7a1ra9hf$.1r69rle8f92yp.dlg@40tude.net>
	<f2361d71-dd8b-45cc-89fc-edf39e57197a@24g2000yqm.googlegroups.com>
Message-ID: <1t9jyo7lzm3ke.hh1blip7i2yp.dlg@40tude.net>

Rainer Joswig wrote:

> I'm not sure if it is fair to post a reference to a single
> post by someone without context and without having used ECL.
> If there are stability problems, people can report to the
> ECL mailing list. The maintainers are very active.

This was just one example. Another one:

http://www.mail-archive.com/application-builder at lispniks.com/msg01024.html

Luke and Elliott are no beginners, so it is at least difficult to use ECL:
On Windows it doesn't work with MinGW and on MacOS X there was at least one
case were it freezed. But as I have written, I didn't tried it myself, so
this is only some second hand experience. Maybe it is all wrong setups in
combination with Lispbuilder and ECL itself is stable, I don't know.

But I know that it is much easier to get a full featured running Python
system on Windows, MacOS X and Linux, so this is something where Lisp
distributions could be improved.

-- 
Frank Buss, fb at frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de


From nagle at animats.com  Tue Jul 21 12:48:38 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 21 Jul 2009 09:48:38 -0700
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system()
	that  doesn't block gui event loops
In-Reply-To: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <4a65f0d8$0$1599$742ec2ed@news.sonic.net>

Ville Vainio wrote:
> Has anyone implementing something like what the subject line
> indicates?
> 
> The idea:
> 
> To run functions that execute a series of system commands without
> blocking the ui, *and* without adding state machine logic.

    At some level, there's going to be state machine logic.
You need interlocking so that the user can't initiate
simultaneous conflicting background operations from the GUI.

    The usual solution is to run the background operations
in another thread, and have them put events on a queue
read by the GUI task.

    You also have to work out how to cancel background operations,
if they're going to be as big as a "make".

    Here's the very first application which did this sort of thing,
running commands in multiple threads without blocking the user
interface thread.  This is from 1972.

    http://www.fourmilab.ch/documents/univac/fang/

    And yes, it did properly interlock everything it was
doing in the background.

				John Nagle


From piet at cs.uu.nl  Tue Jul 21 12:50:00 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 18:50:00 +0200
Subject: Issue combining gzip and subprocess
References: <mailman.3472.1248192725.8015.python-list@python.org>
Message-ID: <m2eisam153.fsf@cs.uu.nl>

>>>>> Iwan Vosloo <iwan at reahl.org> (IV) wrote:

>IV> Hi there,
>IV> We tried to gzip the output of a shell command, but this results in a
>IV> strange error: the resulting file seems to be the concatenation of the
>IV> plaintext file with the zipped content.

>IV> For example:

>IV> f = gzip.open(filename, 'w')
>IV> subprocess.check_call(['ls','-la'], stdout=f)
>IV> f.close()

>IV> Using a normal file works as expected, but a GzipFile results in a file
>IV> containing what looks like the unzipped data, followed by the zipped
>IV> data.

>IV> I suspect this may have something to do with limitations of GzipFile
>IV> such as it not implementing truncate().

>IV> Does anyone have an explanation / can you suggest a nice solution for
>IV> doing what we are trying to do?

stdout (and the others) must be None, PIPE or a real file object or file
descriptor, not a file like object. In your case the solution would be
to use PIPE, and then read the output and write in to the GzipFile
yourself. 

f = gzip.open(filename, 'w')
proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
while True:
    line = proc.stdout.readline()
    if not line: break
    f.write(line)
f.close()

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mail at timgolden.me.uk  Tue Jul 21 13:07:49 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Tue, 21 Jul 2009 18:07:49 +0100
Subject: win32api install problem
In-Reply-To: <b1b9ef55-c740-4a9e-ba33-4aa1e88dc5f5@f33g2000vbm.googlegroups.com>
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>	<mailman.3424.1248098235.8015.python-list@python.org>
	<b1b9ef55-c740-4a9e-ba33-4aa1e88dc5f5@f33g2000vbm.googlegroups.com>
Message-ID: <4A65F5E5.3060903@timgolden.me.uk>

MCIPERF wrote:
> On Jul 20, 9:57 am, Tim Golden <m... at timgolden.me.uk> wrote:
>> Gerry wrote:
>>> I'm running Python 2.6 under XP.
>>> I've installed Windows 32 extensions for Python 2.6 version 1.4
>>> (pywin32-214.win32-py2.6.exe).
>>> But If I try to import win32api, I get:
>>>   File "C:\python_projects\euler\driveletters.py", line 1, in <module>
>>>     import win32api
>>> ImportError: DLL load failed: The specified module could not be found.
>> Used to be you'd get this error if you installed as a
>> non-admin user. Don't know if that's still an issue.
>> Possibility?
>>
>> TJG
> 
> Not a possibility (afaict) -- I am an administrator, according to the
> control panel.

Not too many ideas, then, I'm afraid. Apart from the obvious --
uninstall and try again -- how about running Python with the
-vv option:

python -vv

to get more information about what it's trying to get, 
and/or running sysinternal's Process Explorer at the
same time to spot the DLL Dependencies.

I have seen a (not too similar) problem when running TortoiseHg
and the pywin32 extensions, since the shell import's TortoiseHg's
version of various pywin32 DLLs before I try to import them
myself for some other purpose, and the two versions clashed
dramatically (crashed Explorer hard, I seem to remember).

Just in case that rings any bells..

TJG


From jeanmichel at sequans.com  Tue Jul 21 13:22:05 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 21 Jul 2009 19:22:05 +0200
Subject: Regular expression
In-Reply-To: <op.uxfcgpzua8ncjz@gnudebst>
References: <200907211530.47704.peter.fodrek@stuba.sk>
	<op.uxfcgpzua8ncjz@gnudebst>
Message-ID: <4A65F93D.8000908@sequans.com>

Rhodri James wrote:
> On Tue, 21 Jul 2009 14:30:47 +0100, Peter Fodrek 
> <peter.fodrek at stuba.sk> wrote:
>
>> Dear conference!
>>
>> I have  third party regular expression
>>
>>  self.pattern_main = 
>> re.compile('(\s+|\w(?:[+])?\d*(?:\.\d*)?|\w\#\d+|\(.*?\)|
>> \#\d+\=(?:[+])?\d*(?:\.\d*)?)')
>
> Also, whoever wrote this regular expression should be taken
> out and slapped with a wet fish, for it is abominable and
> unlikely to look much like what you actually want.

Here, take that fish and please, hit really hard !

**                 ;'-. 
     `;-._        )  '---.._
       >  `-.__.-'          `'.__
      /_.-'-._         _,   ^ ---)
      `       `'------/_.'----``


JM
**



From tfb at cley.com  Tue Jul 21 13:41:59 2009
From: tfb at cley.com (Tim Bradshaw)
Date: Tue, 21 Jul 2009 18:41:59 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
Message-ID: <2009072118415916807-tfb@cleycom>

On 2009-07-19 19:31:36 +0100, Frank Buss <fb at frank-buss.de> said:

> (e.g. I
> don't know of a free modern and stable Lisp implemenation with
> mulithreading support for Windows, with a licence with which you can use it
> in closed source commercial programs, like you can do with Python).

Openmcl seems reasonably stable to me, is LLGPL-licensed, and runs on 
these platforms and Solaris x86.

It's kind of tragic, of course, that this kind of parasitic behaviour 
(will not consider a commercial product to use in your commercial 
system) has now become so common.



From robert.kern at gmail.com  Tue Jul 21 13:52:23 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Tue, 21 Jul 2009 12:52:23 -0500
Subject: clean way prepend an element to a numpy array
In-Reply-To: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
Message-ID: <h44v8m$ibu$1@ger.gmane.org>

On 2009-07-20 22:56, bdb112 wrote:
> If I want to add an element at the beginning of an array, it seems
> like I must make a list, insert in place, then make an array again.

the_array = numpy.concatenate([new_value, the_array])

You will want to ask numpy questions on the numpy mailing list.

   http://www.scipy.org/Mailing_Lists

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From rhodri at wildebst.demon.co.uk  Tue Jul 21 13:59:32 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 21 Jul 2009 18:59:32 +0100
Subject: Regular expression
In-Reply-To: <1AE4BD36-9955-4F80-9FBC-6DF62F529CC3@stuba.sk>
References: <200907211530.47704.peter.fodrek@stuba.sk>
	<op.uxfcgpzua8ncjz@gnudebst>
	<1AE4BD36-9955-4F80-9FBC-6DF62F529CC3@stuba.sk>
Message-ID: <op.uxfixifya8ncjz@gnudebst>

On Tue, 21 Jul 2009 17:12:53 +0100, Peter Fodrek <peter.fodrek at stuba.sk>  
wrote:

> 21.7.2009 v 17:39, Rhodri James:
>
>> On Tue, 21 Jul 2009 14:30:47 +0100, Peter Fodrek <peter.fodrek at stuba.sk 
>> > wrote:

[snipped for space]

>>> This handles text file  like
>>>
>>> // remark
>>> PL_OFF
>>> PARK
>>> FS
>>> MA  52.8806 ,  18.0914
>>> SS
>>> AD_W
>>> PL_ON
>>> C   52.3955 ,  -16.1511 ,  -90.0000
>>>
>>> It handles file correctly with two exceptions
>>>
>>> 1) omits ',' in the a output
>>
>> You don't do any output, so it's hard to correct that!
>
> for line
>
> C   52.3955 ,  -16.1511 ,  -90.0000
>
> it returns (as I remember)
>
> ('C', ' ', '52.3955', ' ', ' ', ' 16.1511', ' ', ' ','90.0')
>
> I was to get (number and positions of empty strings are not related to  
> me. I can add, remove then as you wish)
>
> ('C', ' ', '52.3955', ' ', ' ,', ' -16.1511', ' ', ' ,','-90.0')

If whitespace isn't an issue and the format really is as simple as
your example, you don't need the full power of a regular expression
here.  split() would do the trick:

     words = self.line.split()

will return what you want for that example.  It will produce different
(but more consistent) results than the regular expression for other lines,
though: for example,

MA  52.8806 , 18.0914

when put through the regular expression (if fixed for commas) would give  
you

('M', 'A', '  ', '52.8806', ' ', ',', ' ', '18.0914')

as against

['MA', '52.8806', ',', '18.0914']

> I use eval call in python to do format conversion, so just parsing is  
> problem

float() might be better than eval(), if you know for sure that you are
expecting floats.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From fred at bsdhost.net  Tue Jul 21 14:12:01 2009
From: fred at bsdhost.net (Fred C)
Date: Tue, 21 Jul 2009 11:12:01 -0700
Subject: setuptools question.
Message-ID: <AFD34FE4-50D2-4067-A292-7270A4A5C893@bsdhost.net>


I have a python program and when I install this program from the  
module home directory using setup.py everything works fine.

But easy_install fails with the following error, because I am trying  
to install some start up shell scripts into /etc/init.d

 > The package setup script has attempted to modify files on your system
 >that are not within the EasyInstall build area, and has been aborted.

Is there a way to use easy_install to install the start scripts into / 
etc/init.d. If not, what is the best way to install these scripts.

Thanks

-fred-




From hyugaricdeau at gmail.com  Tue Jul 21 14:13:35 2009
From: hyugaricdeau at gmail.com (Hyuga)
Date: Tue, 21 Jul 2009 11:13:35 -0700 (PDT)
Subject: are user defined classes hashable?
References: <AuF8m.271$MA3.73@nwrddc02.gnilink.net>
	<UkG8m.277$MA3.146@nwrddc02.gnilink.net> 
	<mailman.3396.1248018412.8015.python-list@python.org>
	<373d6c69-6965-4a88-bdd2-8028ef850bf8@k6g2000yqn.googlegroups.com>
	<h43aik$oct$1@panix3.panix.com>
Message-ID: <b6ff0bbb-99f4-48eb-8334-8204a43f9d7f@w41g2000yqb.googlegroups.com>

On Jul 20, 10:53?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <373d6c69-6965-4a88-bdd2-8028ef850... at k6g2000yqn.googlegroups.com>,
>
> Hyuga ?<hyugaricd... at gmail.com> wrote:
>
> >Regardless, Nicolas's example can be applied to the class too:
>
> >>>> class Foo(object):
> > ? ?pass
>
> >>>> hash(Foo)
> >11443104
> >>>> id(Foo)
> >11443104
>
> >class objects are just objects of type 'type'.
>
> Not quite. ?They certainly default that way, but changing the metaclass
> changes a class's type::
>
> class M(type):
> ? ? pass
>
> class C(object):
> ? ? pass
>
> class C2(object):
> ? ? __metaclass__ = M
>
> print type(C)
> print type(C2)

Well, okay, you got me there.  But the OP wasn't asking about classes
with different metaclasses.  And besides, type(type(C2)) is still
type ;)


From tjreedy at udel.edu  Tue Jul 21 14:26:39 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Tue, 21 Jul 2009 14:26:39 -0400
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
Message-ID: <h4518v$pua$1@ger.gmane.org>

Nick Craig-Wood wrote:
>
> I tried it on a program I wrote to solve a puzzle (Rush Hour).
> (Actually it solves the meta-puzzle - trying to make the hardest
> possible Rush Hour puzzle.)
> 
> After a bit of twiddling (remove psyco and profiling) I got it to
> start compiling, but unfortunately it compiled for about an hour (in
> iterative type analysis..) used up 600 MB of RAM printing an '*' every
> 10 minutes or so then gave an error message and gave up.
> 
> Unfortunately I shut the window by accident, but the error message was
> something about not being able to resolve types I think with a list of
> 20 or so unresolved types.
> 
> Can you give a hint as to how I debug this?  I presume my program has
> some instances of non static types which is causing the problem, but
> it is going to be a very long debugging session if it takes me an hour
> each cycle ;-)
> 
> The program is about 700 lines of python (excluding comments).

Split it into pieces and compile each separately.
Recurse.

tjr



From tjreedy at udel.edu  Tue Jul 21 14:57:57 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Tue, 21 Jul 2009 14:57:57 -0400
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system()
	that  doesn't block gui event loops
In-Reply-To: <4a65f0d8$0$1599$742ec2ed@news.sonic.net>
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
	<4a65f0d8$0$1599$742ec2ed@news.sonic.net>
Message-ID: <h4533l$vre$1@ger.gmane.org>


> Ville Vainio wrote:
>> Has anyone implementing something like what the subject line
>> indicates?

Your subject line is so long that it is cut off even on my wide screen.
Better to repeat the question in the body.



From martin.hellwig at dcuktec.org  Tue Jul 21 15:05:55 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 21 Jul 2009 20:05:55 +0100
Subject: Running a Python Service under the LocalService or NetworkService
	Account
In-Reply-To: <3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com>
	<fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>
	<3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>
Message-ID: <-vadnaHpJMoIjPvXnZ2dnUVZ8tli4p2d@bt.com>

David Adamo Jr. wrote:
> On Jul 21, 10:40 am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
> wrote:
>> sightseer wrote:
>>
>> <knip>
>>
>>> Error Installing Service: Access is Denied. (5)
>> <knip>
>> Are you trying to do this on windows vista?
>>
>> --
>> MPHhttp://blog.dcuktec.com
>> 'If consumed, best digested with added seasoning to own preference.'
> 
> Yeah, I was trying to do it on Vista. Someone has just helped me out.
> I had to deactivate User Account Control on Windows Vista...and now
> everything is rosy. Thanks guys.

No need to deactivate it, just right click on the command shell program 
and say run as administrator, than you can install the service via the 
command line.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From lukepadawan at gmail.com  Tue Jul 21 15:21:50 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Tue, 21 Jul 2009 16:21:50 -0300
Subject: List insertion cost
Message-ID: <4A66154E.1050200@gmail.com>

Hello,
I would like to know how much it costs to insert an element into a list 
using this operation:
a[2:2] = [ 1 ]
i. e, what is the complexity of the operation above (given that len(a) = n)?

Thanks.


From daniel at stutzbachenterprises.com  Tue Jul 21 15:35:55 2009
From: daniel at stutzbachenterprises.com (Daniel Stutzbach)
Date: Tue, 21 Jul 2009 14:35:55 -0500
Subject: List insertion cost
In-Reply-To: <4A66154E.1050200@gmail.com>
References: <4A66154E.1050200@gmail.com>
Message-ID: <eae285400907211235g7b458efbp73b171296ed901ec@mail.gmail.com>

On Tue, Jul 21, 2009 at 2:21 PM, Lucas P Melo <lukepadawan at gmail.com> wrote:

> I would like to know how much it costs to insert an element into a list
> using this operation:
> a[2:2] = [ 1 ]
> i. e, what is the complexity of the operation above (given that len(a) =
> n)?
>

O(n)

If you want O(log n), you can use the blist extension type from
http://pypi.python.org/pypi/blist/

--
Daniel Stutzbach, Ph.D.
President, Stutzbach Enterprises, LLC <http://stutzbachenterprises.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/4f40afaf/attachment-0001.html>

From king.seth at gmail.com  Tue Jul 21 15:37:12 2009
From: king.seth at gmail.com (Seth)
Date: Tue, 21 Jul 2009 12:37:12 -0700 (PDT)
Subject: Pyserial and pyQt
Message-ID: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>


I have used pyserial in the past but this is my first experience with
pyQt.  I am using the Python xy package for windows current but might
move to linux.  I have a small device that is outputting a basic text
string.  I want to be able to read this string(from the comm port) and
update a text box and eventually a graph in pyQt.  I can't find any
documentation or tutorials on how to do this.  If anyone can point me
in the right direction or give me some tips I would be grateful.

Thanks,
Seth


From robert.kern at gmail.com  Tue Jul 21 15:43:41 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Tue, 21 Jul 2009 14:43:41 -0500
Subject: List insertion cost
In-Reply-To: <4A66154E.1050200@gmail.com>
References: <4A66154E.1050200@gmail.com>
Message-ID: <h455pe$h67$1@ger.gmane.org>

On 2009-07-21 14:21, Lucas P Melo wrote:
> Hello,
> I would like to know how much it costs to insert an element into a list
> using this operation:
> a[2:2] = [ 1 ]
> i. e, what is the complexity of the operation above (given that len(a) =
> n)?

O(n). Python lists are contiguous arrays in memory, and everything after the 
insertion point needs to be moved. Raymond Hettinger has a good talk about the 
implementation of Python lists and other container objects.

http://www.youtube.com/watch?v=hYUsssClE94
http://www.pycon.it/static/stuff/slides/core-python-containers-under-hood.ppt

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From lukepadawan at gmail.com  Tue Jul 21 16:47:26 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Tue, 21 Jul 2009 17:47:26 -0300
Subject: List insertion cost
In-Reply-To: <h455pe$h67$1@ger.gmane.org>
References: <4A66154E.1050200@gmail.com> <h455pe$h67$1@ger.gmane.org>
Message-ID: <4A66295E.9070004@gmail.com>

Robert Kern wrote:
> O(n). Python lists are contiguous arrays in memory, and everything 
> after the insertion point needs to be moved. Raymond Hettinger has a 
> good talk about the implementation of Python lists and other container 
> objects.
>
> http://www.youtube.com/watch?v=hYUsssClE94
> http://www.pycon.it/static/stuff/slides/core-python-containers-under-hood.ppt 
>
Thanks. :)



From ryniek90 at gmail.com  Tue Jul 21 16:55:18 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Tue, 21 Jul 2009 22:55:18 +0200
Subject: Changing the private variables content
In-Reply-To: <mailman.13181.1248195302.8014.python-list@python.org>
References: <mailman.13181.1248195302.8014.python-list@python.org>
Message-ID: <4A662B36.3010708@gmail.com>

Hi.
I'm writing some class, and decided to use inside private method and 
some private variables. While with method i haven't got any problem's 
with variables i have.
Maybe some example.
A class with private method and private variable:

"
 >>> class Secret(object):
    #
    def __init__(self):
        self._number = 1
    #
    def _secret(self):
        print self._number
    def showit(self):
        print "Secret number is:\n"
        self._secret()

 >>> sec = Secret()
 >>> sec.showit()
Secret number is:

1
 >>> sec._number
1
 >>> sec._number = 2
 >>> sec._number
2
 >>> sec._number += 3
 >>> sec._number
5
 >>>
"

As You can see, i made class with private method and private variable 
inside __init__ constructor. I've changed also the variable value, but 
outside class.
I've got problem with changing some variable value _inside__my_ class, 
which i'm writing.
I've searched over google, some tuts with topics about operations on 
private variables, but didn't found anything - only how to make them, 
but no how to assign new objects/override them with new content (and 
other advanced and helpful options).

If someone could help me, it would be great.

Thanks.


From davidj411 at gmail.com  Tue Jul 21 17:00:51 2009
From: davidj411 at gmail.com (davidj411)
Date: Tue, 21 Jul 2009 14:00:51 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
Message-ID: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>

I am using a recursive function to print the time and a few other
things on each pass. ( the function calculates size of file that is
being transferred and if not 100 % copied, it waits 20 secs and checks
again).

i would expect the time to be correct anytime it is used:

<--code below -->>
print time.strftime('%m-%d-%Y %H:%m:%S')
<--code above -->>

here is an example of what i am seeing:

16:07:16
16:07:36
16:07:56
16:07:16
16:07:36
16:07:56
16:07:16
16:07:36
16:07:56


From lukepadawan at gmail.com  Tue Jul 21 17:08:07 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Tue, 21 Jul 2009 18:08:07 -0300
Subject: Balanced binary tree implementation
Message-ID: <4A662E37.6090406@gmail.com>

Hello,

I would like to use a balanced binary tree implementation (preferably 
within some API).
Any hints about where I could find it?

I am looking for something that implements insertion, deletion, search 
and a special search that returns the lesser element bigger than a given 
key [1].

A nice possibility would be an extensible API that allows me to inherit 
its classes and to add operations myself.

Thanks in advance.

[1] Ex: 1 2 3 4 5 6 are elements of the bbt. If I use this operation 
given 4 as the parameter, the value returned would be 5.


From joncle at googlemail.com  Tue Jul 21 17:09:31 2009
From: joncle at googlemail.com (Jon Clements)
Date: Tue, 21 Jul 2009 14:09:31 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
Message-ID: <025efda8-0289-4d7d-a9e8-c90faa445c22@s31g2000yqs.googlegroups.com>

On 21 July, 22:00, davidj411 <davidj... at gmail.com> wrote:
> I am using a recursive function to print the time and a few other
> things on each pass. ( the function calculates size of file that is
> being transferred and if not 100 % copied, it waits 20 secs and checks
> again).
>
> i would expect the time to be correct anytime it is used:
>
> <--code below -->>
> print time.strftime('%m-%d-%Y %H:%m:%S')
> <--code above -->>
>
> here is an example of what i am seeing:
>
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56

I assume month, day and year are actually being output and that you've
removed it from your post.

Err, what else do you expect to happen if you're doing this
recursively?


From gherron at islandtraining.com  Tue Jul 21 17:14:44 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Tue, 21 Jul 2009 14:14:44 -0700
Subject: Changing the private variables content
In-Reply-To: <4A662B36.3010708@gmail.com>
References: <mailman.13181.1248195302.8014.python-list@python.org>
	<4A662B36.3010708@gmail.com>
Message-ID: <4A662FC4.2050804@islandtraining.com>

Ryniek90 wrote:
> Hi.
> I'm writing some class, and decided to use inside private method and 
> some private variables. While with method i haven't got any problem's 
> with variables i have.
> Maybe some example.
> A class with private method and private variable:
>
> "
> >>> class Secret(object):
>    #
>    def __init__(self):
>        self._number = 1
>    #
>    def _secret(self):
>        print self._number
>    def showit(self):
>        print "Secret number is:\n"
>        self._secret()
>
> >>> sec = Secret()
> >>> sec.showit()
> Secret number is:
>
> 1
> >>> sec._number
> 1
> >>> sec._number = 2
> >>> sec._number
> 2
> >>> sec._number += 3
> >>> sec._number
> 5
> >>>
> "
>
> As You can see, i made class with private method and private variable 
> inside __init__ constructor. I've changed also the variable value, but 
> outside class.
> I've got problem with changing some variable value _inside__my_ class, 
> which i'm writing.

Not sure this is what you are asking, but a method (which is how I 
interpret "_inside__my_ class") changes the value by normal assignment 
like this:

class Secret(object):
  ...
  def SetNumber(self,value):
    self._number = value

Is that what you were asking?


Gary Herron



> I've searched over google, some tuts with topics about operations on 
> private variables, but didn't found anything - only how to make them, 
> but no how to assign new objects/override them with new content (and 
> other advanced and helpful options).
>
> If someone could help me, it would be great.
>
> Thanks.



From sajmikins at gmail.com  Tue Jul 21 17:29:14 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 14:29:14 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
Message-ID: <146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>

On Jul 21, 5:00?pm, davidj411 <davidj... at gmail.com> wrote:
> I am using a recursive function to print the time and a few other
> things on each pass. ( the function calculates size of file that is
> being transferred and if not 100 % copied, it waits 20 secs and checks
> again).
>
> i would expect the time to be correct anytime it is used:
>
> <--code below -->>
> print time.strftime('%m-%d-%Y %H:%m:%S')
> <--code above -->>
>
> here is an example of what i am seeing:
>
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56
> 16:07:16
> 16:07:36
> 16:07:56

Your output doesn't match your format string:

In [1]: import time

In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
07-21-2009 17:07:16

There's no way to tell why your output times seem to repeat without
seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
%m:%S')" line.



From piet at cs.uu.nl  Tue Jul 21 17:38:43 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 21 Jul 2009 23:38:43 +0200
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
Message-ID: <m263dln2cc.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:

>d> I am using a recursive function to print the time and a few other
>d> things on each pass. ( the function calculates size of file that is
>d> being transferred and if not 100 % copied, it waits 20 secs and checks
>d> again).

>d> i would expect the time to be correct anytime it is used:

>d> <--code below -->>
>d> print time.strftime('%m-%d-%Y %H:%m:%S')
>d> <--code above -->>

>d> here is an example of what i am seeing:

>d> 16:07:16
>d> 16:07:36
>d> 16:07:56
>d> 16:07:16
>d> 16:07:36
>d> 16:07:56
>d> 16:07:16
>d> 16:07:36
>d> 16:07:56

You probably meant: print time.strftime('%m-%d-%Y %H:%M:%S')
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jeanmichel at sequans.com  Tue Jul 21 17:42:41 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 21 Jul 2009 23:42:41 +0200
Subject: doted filenames in import statements
Message-ID: <4A663651.5020006@sequans.com>

Hi fellows,

I'd like to use the dynamic __import__ statement. It works pretty well 
with non dotted names, but I cannot figure how to make it work with 
dotted file paths.

example:

file = "/home/dsp/test.py"
test = __import__(file)

works like a charm

file = "/home/dsp/4.6.0.0/test.py"
test = __import__(file)
=> no module name blalalal found.

Any suggestion ? I tried multiple escape technics without any success.

JM



From joncle at googlemail.com  Tue Jul 21 17:52:57 2009
From: joncle at googlemail.com (Jon Clements)
Date: Tue, 21 Jul 2009 14:52:57 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<m263dln2cc.fsf@cs.uu.nl>
Message-ID: <577639e9-b64a-4a8e-8d90-b70ca491596b@18g2000yqa.googlegroups.com>

On 21 July, 22:38, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> davidj411 <davidj... at gmail.com> (d) wrote:
> >d> I am using a recursive function to print the time and a few other
> >d> things on each pass. ( the function calculates size of file that is
> >d> being transferred and if not 100 % copied, it waits 20 secs and checks
> >d> again).
> >d> i would expect the time to be correct anytime it is used:
> >d> <--code below -->>
> >d> print time.strftime('%m-%d-%Y %H:%m:%S')
> >d> <--code above -->>
> >d> here is an example of what i am seeing:
> >d> 16:07:16
> >d> 16:07:36
> >d> 16:07:56
> >d> 16:07:16
> >d> 16:07:36
> >d> 16:07:56
> >d> 16:07:16
> >d> 16:07:36
> >d> 16:07:56
>
> You probably meant: print time.strftime('%m-%d-%Y %H:%M:%S')
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

Good spot!


From davidj411 at gmail.com  Tue Jul 21 17:53:29 2009
From: davidj411 at gmail.com (davidj411)
Date: Tue, 21 Jul 2009 14:53:29 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
Message-ID: <dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>

On Jul 21, 5:29?pm, Simon Forman <sajmik... at gmail.com> wrote:
> On Jul 21, 5:00?pm, davidj411 <davidj... at gmail.com> wrote:
>
>
>
>
>
> > I am using a recursive function to print the time and a few other
> > things on each pass. ( the function calculates size of file that is
> > being transferred and if not 100 % copied, it waits 20 secs and checks
> > again).
>
> > i would expect the time to be correct anytime it is used:
>
> > <--code below -->>
> > print time.strftime('%m-%d-%Y %H:%m:%S')
> > <--code above -->>
>
> > here is an example of what i am seeing:
>
> > 16:07:16
> > 16:07:36
> > 16:07:56
> > 16:07:16
> > 16:07:36
> > 16:07:56
> > 16:07:16
> > 16:07:36
> > 16:07:56
>
> Your output doesn't match your format string:
>
> In [1]: import time
>
> In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
> 07-21-2009 17:07:16
>
> There's no way to tell why your output times seem to repeat without
> seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
> %m:%S')" line.

sorry, yes, i did manually filter the output.

here is the function:

def log_out(msg,servername='std.out'):
	print msg
	open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
+ time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')

on each pass, it should output the newer time (whether recursive or
not, right) ?


From clp2 at rebertia.com  Tue Jul 21 17:59:17 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 21 Jul 2009 14:59:17 -0700
Subject: doted filenames in import statements
In-Reply-To: <4A663651.5020006@sequans.com>
References: <4A663651.5020006@sequans.com>
Message-ID: <50697b2c0907211459w88c3e28y2a96811bd307233c@mail.gmail.com>

On Tue, Jul 21, 2009 at 2:42 PM, Jean-Michel
Pichavant<jeanmichel at sequans.com> wrote:
> Hi fellows,
>
> I'd like to use the dynamic __import__ statement. It works pretty well with
> non dotted names, but I cannot figure how to make it work with dotted file
> paths.
>
> example:
>
> file = "/home/dsp/test.py"
> test = __import__(file)
>
> works like a charm
>
> file = "/home/dsp/4.6.0.0/test.py"
> test = __import__(file)
> => no module name blalalal found.
>
> Any suggestion ? I tried multiple escape technics without any success.

You want the imp.load_module() function:
http://docs.python.org/library/imp.html#imp.load_module

__import__() only operates on module/package names. I'm not sure how
you even got it to work with a filename...

Cheers,
Chris
-- 
http://blog.rebertia.com


From rhodri at wildebst.demon.co.uk  Tue Jul 21 18:00:39 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Tue, 21 Jul 2009 23:00:39 +0100
Subject: Changing the private variables content
In-Reply-To: <4A662B36.3010708@gmail.com>
References: <mailman.13181.1248195302.8014.python-list@python.org>
	<4A662B36.3010708@gmail.com>
Message-ID: <op.uxft3d05a8ncjz@gnudebst>

On Tue, 21 Jul 2009 21:55:18 +0100, Ryniek90 <ryniek90 at gmail.com> wrote:

> Hi.
> I'm writing some class, and decided to use inside private method and  
> some private variables. While with method i haven't got any problem's  
> with variables i have.

There is no mechanism in Python that makes attributes truly private.
self._number is an attribute just like any other, the whole business
with _leading_underscores is purely a matter of convention.  If you
have an instance attribute or method with a leading underscore, you
know that using it or calling it isn't something you're supposed
to do outside its class, but nothing will stop you doing exactly that
if you're rude enough to try.

Does that help?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From piet at cs.uu.nl  Tue Jul 21 18:01:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 00:01:35 +0200
Subject: Balanced binary tree implementation
References: <mailman.3486.1248210495.8015.python-list@python.org>
Message-ID: <m21vo9n1a8.fsf@cs.uu.nl>

>>>>> Lucas P Melo <lukepadawan at gmail.com> (LPM) wrote:

>LPM> Hello,
>LPM> I would like to use a balanced binary tree implementation (preferably
>LPM> within some API).
>LPM> Any hints about where I could find it?

>LPM> I am looking for something that implements insertion, deletion, search and
>LPM> a special search that returns the lesser element bigger than a given key
>LPM> [1].

>LPM> A nice possibility would be an extensible API that allows me to inherit its
>LPM> classes and to add operations myself.

>LPM> Thanks in advance.

>LPM> [1] Ex: 1 2 3 4 5 6 are elements of the bbt. If I use this operation given
>LPM> 4 as the parameter, the value returned would be 5.

http://newcenturycomputers.net/projects/rbtree.html (warning: see end of
page!)

http://pypi.python.org/pypi/rbtree/

http://pyavl.sourceforge.net/

http://code.activestate.com/recipes/576817/
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at mrabarnett.plus.com  Tue Jul 21 18:04:39 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 21 Jul 2009 23:04:39 +0100
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
In-Reply-To: <dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
Message-ID: <4A663B77.3020408@mrabarnett.plus.com>

davidj411 wrote:
> On Jul 21, 5:29 pm, Simon Forman <sajmik... at gmail.com> wrote:
>> On Jul 21, 5:00 pm, davidj411 <davidj... at gmail.com> wrote:
>>
>>
>>
>>
>>
>>> I am using a recursive function to print the time and a few other
>>> things on each pass. ( the function calculates size of file that is
>>> being transferred and if not 100 % copied, it waits 20 secs and checks
>>> again).
>>> i would expect the time to be correct anytime it is used:
>>> <--code below -->>
>>> print time.strftime('%m-%d-%Y %H:%m:%S')
>>> <--code above -->>
>>> here is an example of what i am seeing:
>>> 16:07:16
>>> 16:07:36
>>> 16:07:56
>>> 16:07:16
>>> 16:07:36
>>> 16:07:56
>>> 16:07:16
>>> 16:07:36
>>> 16:07:56
>> Your output doesn't match your format string:
>>
>> In [1]: import time
>>
>> In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
>> 07-21-2009 17:07:16
>>
>> There's no way to tell why your output times seem to repeat without
>> seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
>> %m:%S')" line.
> 
> sorry, yes, i did manually filter the output.
> 
> here is the function:
> 
> def log_out(msg,servername='std.out'):
> 	print msg
> 	open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
> + time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')
> 
> on each pass, it should output the newer time (whether recursive or
> not, right) ?

Maybe it does, but you were outputting the month ("07") instead of the
minutes; the seconds were changing.


From piet at cs.uu.nl  Tue Jul 21 18:11:38 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 00:11:38 +0200
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
Message-ID: <m2tz15lm91.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:
>>> 
>>> > <--code below -->>
>>> > print time.strftime('%m-%d-%Y %H:%m:%S')
>>> > <--code above -->>

>d> here is the function:

>d> def log_out(msg,servername='std.out'):
>d> 	print msg
>d> 	open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
>d> + time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')

>d> on each pass, it should output the newer time (whether recursive or
>d> not, right) ?

How come your strftime is now different from the first posting? Are you
cheating? 

If you want to ask a question about why your code is not working
properly there are a few important rules:

1. Copy and paste your code, and at least all relevant stuff (preferably
   a minimal example that shows the problem). *DO NOT RETYPE THE CODE*

2. Copy and paste the output. *DO NOT RETYPE THE OUTPUT*

3. Tell what the expected or desired output is.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Tue Jul 21 18:29:52 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 00:29:52 +0200
Subject: doted filenames in import statements
References: <mailman.3488.1248212574.8015.python-list@python.org>
Message-ID: <m2prbtllen.fsf@cs.uu.nl>

>>>>> Jean-Michel Pichavant <jeanmichel at sequans.com> (JP) wrote:

>JP> Hi fellows,
>JP> I'd like to use the dynamic __import__ statement. It works pretty well with
>JP> non dotted names, but I cannot figure how to make it work with dotted file
>JP> paths.

What is a dotted file path? Is that 4.6.0.0?

>JP> example:

>JP> file = "/home/dsp/test.py"
>JP> test = __import__(file)

>JP> works like a charm

That's not supposed to work. In older pythons it did work but that's a
bug. In newer pythons it doesn't. __import__ works on module names, not
on file names.

Python 2.6:

>>> spam = __import__('/Users/piet/TEMP/test.py', globals(), locals(), [], -1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: Import by filename is not supported.
>>> 

>JP> file = "/home/dsp/4.6.0.0/test.py"
>JP> test = __import__(file)
>JP> => no module name blalalal found.

>JP> Any suggestion ? I tried multiple escape technics without any success.

Rightly so.

I think the best would be to add the directory to sys.path 
sys.path.add('/home/dsp/4.6.0.0')
and then
__import__('test', ... ) 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From emile at fenx.com  Tue Jul 21 18:37:40 2009
From: emile at fenx.com (Emile van Sebille)
Date: Tue, 21 Jul 2009 15:37:40 -0700
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <7xiqho1c2i.fsf@ruckus.brouhaha.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>	<roy-362564.15092819072009@news.panix.com>	<h3vu2m$um2$1@ger.gmane.org>	<mailman.3407.1248038041.8015.python-list@python.org>
	<7xiqho1c2i.fsf@ruckus.brouhaha.com>
Message-ID: <h45g3h$g9r$1@ger.gmane.org>

On 7/19/2009 4:35 PM Paul Rubin said...
> Emile van Sebille <emile at fenx.com> writes:
>>>> Most people would still consider Solaris to be a "major platform".
>>> ?? I do not, but I have no idea what comes in 4th after the other
>>> three by whatever metric.
>> one metric calls fourth as the iPhone OS...
>> http://marketshare.hitslink.com/report.aspx?qprid=8...
> 
> That metric is clearly wrong.  The #1 platform OS platform in terms of
> number of units shipped is Javacard, which is in the SIM cards of
> billions of GSM phones.

Yes -- that location includes disclaimers on how they reach their 
conclusions.



From lists at cheimes.de  Tue Jul 21 18:48:40 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 22 Jul 2009 00:48:40 +0200
Subject: doted filenames in import statements
In-Reply-To: <50697b2c0907211459w88c3e28y2a96811bd307233c@mail.gmail.com>
References: <4A663651.5020006@sequans.com>
	<50697b2c0907211459w88c3e28y2a96811bd307233c@mail.gmail.com>
Message-ID: <h45gk8$hj6$1@ger.gmane.org>

Chris Rebert wrote:
> You want the imp.load_module() function:
> http://docs.python.org/library/imp.html#imp.load_module
> 
> __import__() only operates on module/package names. I'm not sure how
> you even got it to work with a filename...

It used to work with filenames but it was a bug. I guess several people
are swearing curses on me for removing this 'feature'. *g*

Christian



From ebonak at hotmail.com  Tue Jul 21 19:06:01 2009
From: ebonak at hotmail.com (Esmail)
Date: Tue, 21 Jul 2009 19:06:01 -0400
Subject: comments? storing a function in an object
In-Reply-To: <h425ks$fo7$1@ger.gmane.org>
References: <h425ks$fo7$1@ger.gmane.org>
Message-ID: <h45hko$k4h$1@ger.gmane.org>

Thanks *everyone* for your help, and sharing your knowledge.

I had no idea that Python functions could have user defined
attributes, and I may now not even need the object to wrap
my functions in.

Amazing what one can learn here .. thanks again!

Esmail



From nyamatongwe+thunder at gmail.com  Tue Jul 21 19:06:02 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Tue, 21 Jul 2009 23:06:02 GMT
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
Message-ID: <uRr9m.6558$ze1.5162@news-server.bigpond.net.au>

milanj:

> and all of them use native threads (python still use green threads ?)

   Python uses native threads.

   Neil


From david at boddie.org.uk  Tue Jul 21 19:24:32 2009
From: david at boddie.org.uk (David Boddie)
Date: Wed, 22 Jul 2009 01:24:32 +0200
Subject: Pyserial and pyQt
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
Message-ID: <h45inh$ofk$1@get-news01.get.basefarm.net>

On Tuesday 21 July 2009 21:37, Seth wrote:

> I have used pyserial in the past but this is my first experience with
> pyQt.  I am using the Python xy package for windows current but might
> move to linux.  I have a small device that is outputting a basic text
> string.  I want to be able to read this string(from the comm port) and
> update a text box and eventually a graph in pyQt.  I can't find any
> documentation or tutorials on how to do this.  If anyone can point me
> in the right direction or give me some tips I would be grateful.

It seems that someone has already asked a similar question on Stack
Overflow, though perhaps you should start with a simpler solution
and look at more advanced ones later:

  http://stackoverflow.com/questions/771988/pyqt4-and-pyserial

One starting point is this list of tutorials on the PyQt and PyKDE Wiki:

  http://www.diotavelli.net/PyQtWiki/Tutorials

Later, when you want to draw graphs, you might find PyQwt useful:

  http://pyqwt.sourceforge.net/

You may already be aware that there's also a mailing list for PyQt and
PyKDE:

  http://www.riverbankcomputing.com/pipermail/pyqt/

Another way to get answers to questions is to join the #pyqt IRC channel
at freenode.net:

  irc://irc.freenode.net/

David


From david.lyon at preisshare.net  Tue Jul 21 19:48:24 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 21 Jul 2009 19:48:24 -0400
Subject: setuptools question.
In-Reply-To: <AFD34FE4-50D2-4067-A292-7270A4A5C893@bsdhost.net>
References: <AFD34FE4-50D2-4067-A292-7270A4A5C893@bsdhost.net>
Message-ID: <21107bd58153b0a10d52ce5d3d9b70db@preisshare.net>

On Tue, 21 Jul 2009 11:12:01 -0700, Fred C <fred at bsdhost.net> wrote:
> I have a python program and when I install this program from the  
> module home directory using setup.py everything works fine.
> 
> But easy_install fails with the following error, because I am trying  
> to install some start up shell scripts into /etc/init.d
> 
>  > The package setup script has attempted to modify files on your system
>  >that are not within the EasyInstall build area, and has been aborted.
> 
> Is there a way to use easy_install to install the start scripts into / 
> etc/init.d. If not, what is the best way to install these scripts.

What package is it? what platform ?


From sajmikins at gmail.com  Tue Jul 21 19:59:21 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Tue, 21 Jul 2009 16:59:21 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com> 
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
Message-ID: <16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com>

On Jul 21, 5:53?pm, davidj411 <davidj... at gmail.com> wrote:
> On Jul 21, 5:29?pm, Simon Forman <sajmik... at gmail.com> wrote:
>
>
>
> > On Jul 21, 5:00?pm, davidj411 <davidj... at gmail.com> wrote:
>
> > > I am using a recursive function to print the time and a few other
> > > things on each pass. ( the function calculates size of file that is
> > > being transferred and if not 100 % copied, it waits 20 secs and checks
> > > again).
>
> > > i would expect the time to be correct anytime it is used:
>
> > > <--code below -->>
> > > print time.strftime('%m-%d-%Y %H:%m:%S')
> > > <--code above -->>
>
> > > here is an example of what i am seeing:
>
> > > 16:07:16
> > > 16:07:36
> > > 16:07:56
> > > 16:07:16
> > > 16:07:36
> > > 16:07:56
> > > 16:07:16
> > > 16:07:36
> > > 16:07:56
>
> > Your output doesn't match your format string:
>
> > In [1]: import time
>
> > In [2]: print time.strftime('%m-%d-%Y %H:%m:%S')
> > 07-21-2009 17:07:16
>
> > There's no way to tell why your output times seem to repeat without
> > seeing the code that surrounds your "print time.strftime('%m-%d-%Y %H:
> > %m:%S')" line.
>
> sorry, yes, i did manually filter the output.
>
> here is the function:
>
> def log_out(msg,servername='std.out'):
> ? ? ? ? print msg
> ? ? ? ? open(log_dir + '\\' + servername + ".log",'a').write(servername + "-"
> + time.strftime('%m-%d-%Y %H:%M:%S') + " " + msg+'\n')
>
> on each pass, it should output the newer time (whether recursive or
> not, right) ?

Well, as Piet van Oostrum pointed out, your problem in the first code
you posted was that you used '%m' rather than '%M' for the minutes.
(Good eye Van Oostrum!)  But now in this function you seem to have the
correct '%M' field.  Are you still having the same output after
changing that?


In any event, here's a rewritten version of that function that's a
little cleaner, FWIW.


from os.path import join
from time import strftime

format = '%m-%d-%Y %H:%M:%S'

def log_out(msg, servername='std.out'):
    print msg
    msg = "%s - %s %s\n" % (servername, strftime(format), msg)
    log_file = open(join(log_dir, servername + ".log"), 'a')
    try:
        log_file.write(msg)
    finally:
        log_file.close()


But why not just use the logging module?


From mail.to.daniel.platz at googlemail.com  Tue Jul 21 20:00:13 2009
From: mail.to.daniel.platz at googlemail.com (Daniel Platz)
Date: Tue, 21 Jul 2009 17:00:13 -0700 (PDT)
Subject: Fast reading and unpacking of binary data (struct module)
Message-ID: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>

Hi,

I have a Python newbie question about reading data from a binary file.
I have an huge binary file from an external program. I want to read
and process the data in this file in a reasonable time. It turns out
that the reading of the data itself and the processing do not need
most of the time. However, when using the read(bytes) method Python
returns a string representing the binary information in hex. This
string I have to "cast/translate" into a number (in my case a signed
short). For this I am using the method struct.unpack from the struct
module. This unpacking part of the program takes by far the most time.
Is there a way to speed this up or to do it the unpacking more
cleverly than with the struct module?

Thanks in advance.

With kind regards,

Daniel


From ronn.ross at gmail.com  Tue Jul 21 20:08:57 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Tue, 21 Jul 2009 19:08:57 -0500
Subject: trouble with minidom
Message-ID: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>

Hello I'm trying to read an xml file using minidome. The xml looks like:
<rootNode>
   <project>
      <name>myProj</name>
      <path>/here/</path>
   </project>
</rootNode>

My code looks like so:
from xml.dom.minidom import parse

dom = parse("myfile.xml")

for node in dom.getElementsByTagName("project'):
   print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,
node.childNodes[1])

Unfortunately, it returns 'nodeValue as none. I'm trying to read the value
out of the node fir example name: myProj. I haven't found much help in the
documentation. Can someone point me in the right direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/809e2fa2/attachment-0001.html>

From gagsl-py2 at yahoo.com.ar  Tue Jul 21 20:18:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 21:18:42 -0300
Subject: Fast reading and unpacking of binary data (struct module)
References: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>
Message-ID: <op.uxf0hglwx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 21 Jul 2009 21:00:13 -0300, Daniel Platz  
<mail.to.daniel.platz at googlemail.com> escribi?:

> I have an huge binary file from an external program. I want to read
> and process the data in this file in a reasonable time. It turns out
> that the reading of the data itself and the processing do not need
> most of the time. However, when using the read(bytes) method Python
> returns a string representing the binary information in hex. This
> string I have to "cast/translate" into a number (in my case a signed
> short). For this I am using the method struct.unpack from the struct
> module. This unpacking part of the program takes by far the most time.
> Is there a way to speed this up or to do it the unpacking more
> cleverly than with the struct module?

Try creating a Struct object with your format and use its unpack() method.
http://docs.python.org/library/struct.html#struct-objects

If your format consists of just integers, probably an array is more  
efficient:
http://docs.python.org/library/array.html#array.array.fromfile

-- 
Gabriel Genellina



From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:18:44 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:18:44 +1200
Subject: tough-to-explain Python
In-Reply-To: <11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7cimf0F27u23eU1@mid.individual.net>
	<11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>
Message-ID: <7cn45nF28j1d4U1@mid.individual.net>

Simon Forman wrote:

> My understanding (so far) is that you (hope to) /derive/ correct code
> using formal logic, rather than writing code and then proving its
> soundness.

But to the extent you can rigorously formalise it,
all you've done is create Yet Another Programming
Language.

Which is fine, if you can come up with one that
works at a high enough level in some domain that
you can see just by looking that the program will
do what you want.

However, I suspect that you can't improve much on
what we've already got without restricting the
domain of applicability of the language. Otherwise,
you just shift the intellectual bottleneck from
writing a correct program to writing correct
specifications.

In the realm of programming language design, it's
been said that you can't eliminate complexity, all
you can do is push it around from one place to
another. I suspect something similar applies to
the difficulty of writing programs.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:28:39 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:28:39 +1200
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <87skgq8m7s.fsf@benfinney.id.au>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com>
	<87skgq8m7s.fsf@benfinney.id.au>
Message-ID: <7cn4obF286u4kU1@mid.individual.net>

Ben Finney wrote:
> My point was rather meant to imply that
> subclassing the built-in (immutable) string types was the best way to
> usefully get all their functionality

However, it would be difficult to do that without changing
all C code that deals with strings, including that in extension
modules.

That's because the existing string type stores the characters
in the string object itself. A mutable variant would have to
contain a pointer to a resizable memory block, and therefore
couldn't be used as a drop-in replacement by existing C
code that expects a string.

-- 
Greg


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 20:32:03 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 21:32:03 -0300
Subject: trouble with minidom
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
Message-ID: <op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 21 Jul 2009 21:08:57 -0300, Ronn Ross <ronn.ross at gmail.com>  
escribi?:

> Hello I'm trying to read an xml file using minidome. The xml looks like:
> <rootNode>
>    <project>
>       <name>myProj</name>
>       <path>/here/</path>
>    </project>
> </rootNode>
>
> My code looks like so:
> from xml.dom.minidom import parse
>
> dom = parse("myfile.xml")
>
> for node in dom.getElementsByTagName("project'):
>    print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,
> node.childNodes[1])
>
> Unfortunately, it returns 'nodeValue as none. I'm trying to read the  
> value
> out of the node fir example name: myProj. I haven't found much help in  
> the
> documentation. Can someone point me in the right direction?

Unless you have a specific reason to use the DOM interface (like having a  
masochistic mind), working with ElementTree usually is a lot easier:

py> import xml.etree.ElementTree as ET
py> xml = """<rootNode>
... <project>
...        <name>myProj</name>
...        <path>/here/</path>
... </project>
... </rootNode>"""
py> doc = ET.fromstring(xml)
py> for project in doc.findall('project'):
...   for child in project.getchildren():
...     print child.tag, child.text
...
name myProj
path /here/

-- 
Gabriel Genellina



From khanhqh2008i at gmail.com  Tue Jul 21 20:32:22 2009
From: khanhqh2008i at gmail.com (khanh le)
Date: Wed, 22 Jul 2009 07:32:22 +0700
Subject: Python
Message-ID: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>

do you have any materials about Python?
can you show me the link of Python or some books?
thanks a lots!

-- 
Regard!
Khanh
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/2749be50/attachment-0001.html>

From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:35:18 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:35:18 +1200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <4a645b81$0$12974$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
Message-ID: <7cn54pF28nv72U1@mid.individual.net>

William Dode wrote:

> I just tested it with a litle game, to find the places of horse on 
> a board 5x5. The result is :
> 
> cython avec malloc *int 18s

Posting benchmark times for Pyrex or Cython is pretty
meaningless without showing the exact code that was
used, since times can vary enormously depending on
how much you C-ify things.

-- 
Greg


From david.lyon at preisshare.net  Tue Jul 21 20:37:50 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Tue, 21 Jul 2009 20:37:50 -0400
Subject: Python
In-Reply-To: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
Message-ID: <00e687679e63af535bea6a4046f1df08@preisshare.net>

On Wed, 22 Jul 2009 07:32:22 +0700, khanh le <khanhqh2008i at gmail.com>
wrote:
> do you have any materials about Python?
> can you show me the link of Python or some books?

http://www.python.org/

> thanks a lots!

No problem. Have a nice day.


From casey.mcginty at gmail.com  Tue Jul 21 20:43:27 2009
From: casey.mcginty at gmail.com (Casey McGinty)
Date: Tue, 21 Jul 2009 14:43:27 -1000
Subject: SMTPlib and SMTPd Performance Issues
Message-ID: <ae3f58470907211743m68570739v6524b551190ea83a@mail.gmail.com>

Hi,

I just wanted mention a few workarounds I've come up with for the Python
SMTP modules in regards to performance.

Before I started, I was getting about 15MB/s while sending e-mail from
smtplib to smptd over a local connection. (i.e. both client/server running
on the same machine). After the following changes, I'm seeing around*220+MB/s
* (increase of 14x)

The source can be found here:
http://svn.python.org/view/python/trunk/Lib/smtplib.py?view=markup
http://svn.python.org/view/python/trunk/Lib/smtpd.py?view=markup

When sending e-mail through *smtpdlib*, the following method is called.

def quotedata(data):
    """Quote data for email.

    Double leading '.', and change Unix newline '\\n', or Mac '\\r' into
    Internet CRLF end-of-line.
    """
    return re.sub(r'(?m)^\.', '..',
        re.sub(r'(?:\r\n|\n|\r(?!\n))', CRLF, data))


As you can see there are two regular expressions parsing the data. If you
know that your message is formatted correctly to start with, then this step
is unnecessary.

When receiving e-mail through *smtpd*, the SMTPChannel class inherits from *
asynchat.async_chat*. The default recv buffer size for asynchat is 4K. This
can be too much overhead for high data throughput. The buffer size can be
increased with this code:

import asynchat
asynchat.async_chat.ac_in_buffer_size  = 1024*128
asynchat.async_chat.ac_out_buffer_size = 1024*128

The *smtpd.SMTP* class prcoesses data through the *smtpd.SMTPChannel* class.
There are a lot of debug statements in the module, like so:

print >> DEBUGSTREAM, 'Data:', repr(line)

By default, DEBUGSTREAM is a no-op, but that that doesn't prevent
repr(line) from being called. When variable, line, contains a large
email (multiple megabytes),
this debug step will really kill performance.

Secondly, the method *found_terminator* will also perform expensive
strings ops on the e-mail. Maybe its not possible to disable this
step, in all cases,
but for testing performance, you can override the method like so:

class QuickSMTPChannel( smtpd.SMTPChannel, object):
   def found_terminator(self):
      if (self._SMTPChannel__state == self.COMMAND or
            self._SMTPChannel__state != self.DATA):
         super(QuickSMTPChannel,self).found_terminator()
      else:
         data = smtpd.EMPTYSTRING.join(self._SMTPChannel__line)
         self._SMTPChannel__line = []
         status = self._SMTPChannel__server.process_message(
               self._SMTPChannel__peer, self._SMTPChannel__mailfrom,
               self._SMTPChannel__rcpttos, data)
         self._SMTPChannel__rcpttos = []
         self._SMTPChannel__mailfrom = None
         self._SMTPChannel__state = self.COMMAND
         self.set_terminator('\r\n')
         if not status:
             self.push('250 Ok')
         else:
             self.push(status

Thanks,

- Casey
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090721/30af3af7/attachment-0001.html>

From greg at cosc.canterbury.ac.nz  Tue Jul 21 20:47:35 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 12:47:35 +1200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<pan.2009.07.20.05.11.18@REMOVE.THIS.cybersource.com.au>
	<7x4ot7rif8.fsf@ruckus.brouhaha.com>
	<fe7c6250-5008-4a71-a0ac-1bd49950df50@r2g2000yqm.googlegroups.com>
Message-ID: <7cn5rqF28emnnU1@mid.individual.net>

>>Steven D'Aprano <ste... at REMOVE.THIS.cybersource.com.au> writes:
>>
>>>Besides, one can legitimately disagree that 2/3 => 0 is the wrong thing
>>>to do. It's the right thing to do if you're doing integer maths.

True, but the question is how best to decide whether the
programmer wants to do integer maths.

Deciding based on the types of the operands is okay in a
statically typed language. But it's asking for trouble in
a dynamically-typed language, especially where it's common
practice to use ints as a substitute for floats that
happen to have integer values.

EIBTI in this case.

-- 
Greg


From http  Tue Jul 21 21:07:24 2009
From: http (Paul Rubin)
Date: 21 Jul 2009 18:07:24 -0700
Subject: tough-to-explain Python
References: <h309ot$bii$1@reader1.panix.com>
	<5f0a2722-45eb-468c-b6b2-b7bb80ae5f19@q11g2000yqi.googlegroups.com>
	<h3234l$aod$1@reader1.panix.com>
	<mailman.2839.1247060874.8015.python-list@python.org>
	<b9dccb70-816c-48a2-a1a5-ac4c9d0b8d5b@c9g2000yqm.googlegroups.com>
	<00720d76$0$9710$c3e8da3@news.astraweb.com>
	<6973dc43-4d3d-41fa-99d0-67aed42e5bd6@g31g2000yqc.googlegroups.com>
	<7cimf0F27u23eU1@mid.individual.net>
	<11d09c87-1cd0-45be-b921-ef1811c97723@k6g2000yqn.googlegroups.com>
	<7cn45nF28j1d4U1@mid.individual.net>
Message-ID: <7x4ot5bk4z.fsf@ruckus.brouhaha.com>

greg <greg at cosc.canterbury.ac.nz> writes:
> However, I suspect that you can't improve much on what we've already
> got without restricting the domain of applicability of the
> language. Otherwise, you just shift the intellectual bottleneck from
> writing a correct program to writing correct specifications.

Really, it's easier to write specifications.  They're a level of
abstraction away from the implementation.  Think of a sorting
function that operates on a list a1,a2...a_n.  The sorting algorithm
might be some fiendishly clever, hyper-optimized hybrid of quicksort,
heapsort, timsort, burstsort, and 52-pickup.  It might be thousands
of lines of intricate code that looks like it could break at the
slightest glance.  The specification simply says the output
has the property a1<=a2<=...<=a_n.  That is a lot easier to
say.  If you can then prove that the program satisfies the
specification, you are far better off than if you have some
super-complex pile of code that appears to sort when you test
it, but has any number of possible edge cases that you didn't
figure out needed testing.  It's like the difference between
stating a mathematical theorem (like the four-color theorem)
and proving it.


From pjb at informatimago.com  Tue Jul 21 21:19:19 2009
From: pjb at informatimago.com (Pascal J. Bourguignon)
Date: Wed, 22 Jul 2009 03:19:19 +0200
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<2009072118415916807-tfb@cleycom>
Message-ID: <87my6xa50o.fsf@galatea.local>

Tim Bradshaw <tfb at cley.com> writes:

> On 2009-07-19 19:31:36 +0100, Frank Buss <fb at frank-buss.de> said:
>
>> (e.g. I
>> don't know of a free modern and stable Lisp implemenation with
>> mulithreading support for Windows, with a licence with which you can use it
>> in closed source commercial programs, like you can do with Python).
>
> Openmcl seems reasonably stable to me, is LLGPL-licensed, and runs on
> these platforms and Solaris x86.
>
> It's kind of tragic, of course, that this kind of parasitic behaviour
> (will not consider a commercial product to use in your commercial
> system) has now become so common.

GPL.

-- 
__Pascal Bourguignon__


From dstanek at dstanek.com  Tue Jul 21 22:05:46 2009
From: dstanek at dstanek.com (David Stanek)
Date: Tue, 21 Jul 2009 22:05:46 -0400
Subject: Changing the private variables content
In-Reply-To: <op.uxft3d05a8ncjz@gnudebst>
References: <mailman.13181.1248195302.8014.python-list@python.org>
	<4A662B36.3010708@gmail.com> <op.uxft3d05a8ncjz@gnudebst>
Message-ID: <de32cc030907211905t570aba18wcd60ecce07c3d873@mail.gmail.com>

On Tue, Jul 21, 2009 at 6:00 PM, Rhodri
James<rhodri at wildebst.demon.co.uk> wrote:
> On Tue, 21 Jul 2009 21:55:18 +0100, Ryniek90 <ryniek90 at gmail.com> wrote:
>
>> Hi.
>> I'm writing some class, and decided to use inside private method and some
>> private variables. While with method i haven't got any problem's with
>> variables i have.
>
> There is no mechanism in Python that makes attributes truly private.
> self._number is an attribute just like any other, the whole business
> with _leading_underscores is purely a matter of convention. ?If you
> have an instance attribute or method with a leading underscore, you
> know that using it or calling it isn't something you're supposed
> to do outside its class, but nothing will stop you doing exactly that
> if you're rude enough to try.
>

Doubling the _ will give you a little more privacy. It really just
mangles the attribute name, but it close to what you want.

I just use a _single_under to tell other programmers that they
shouldn't be accessing that attribute directly. To my knowledge
nothing bad has happened because things are public and using the
__double_under makes testing a little harder.

  >>> class C(object):
  ...     def __init__(self):
  ...         self.__x = 0
  ...
  >>> c = C()
  >>> c.__x
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  AttributeError: 'C' object has no attribute '__x'
  >>> c._C__x
  0


-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From gagsl-py2 at yahoo.com.ar  Tue Jul 21 22:18:26 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 21 Jul 2009 23:18:26 -0300
Subject: Python
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
	<00e687679e63af535bea6a4046f1df08@preisshare.net>
Message-ID: <op.uxf500qnx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 21 Jul 2009 21:37:50 -0300, David Lyon <david.lyon at preisshare.net>  
escribi?:
> On Wed, 22 Jul 2009 07:32:22 +0700, khanh le <khanhqh2008i at gmail.com>
> wrote:

>> do you have any materials about Python?
>> can you show me the link of Python or some books?
>
> http://www.python.org/

Also see http://wiki.python.org/moin/BeginnersGuide

-- 
Gabriel Genellina



From prateekkakirwar at gmail.com  Wed Jul 22 00:42:39 2009
From: prateekkakirwar at gmail.com (Prateek)
Date: Tue, 21 Jul 2009 21:42:39 -0700 (PDT)
Subject: Python
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com> 
	<00e687679e63af535bea6a4046f1df08@preisshare.net>
	<mailman.3503.1248229122.8015.python-list@python.org>
Message-ID: <6281cf33-8ab6-4ff6-a2c5-a9fa1e66d368@m7g2000prd.googlegroups.com>

Chk dis out ...

http://www.swaroopch.com/notes/Python

It's gr8 guide for beginners

Cheers!!!
Prateek


From gagsl-py2 at yahoo.com.ar  Wed Jul 22 01:02:55 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 02:02:55 -0300
Subject: Detect target name in descriptor __set__ method
Message-ID: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>

I have a class attribute 'foo' which is a data descriptor. I create an  
instance of such class. When I say instance.foo = value, the descriptor  
__set__ method is called. Is there any way to obtain the name being  
assigned to? ('foo' in this example). That is, I want to know the target  
name for the assignment that triggered the __set__ method call.

class descriptor(object):
   def __get__(self, instance, owner):
     print 'descriptor.__get__ self=%r instance=%r owner=%r' % (
       self, instance, owner)
     return self

   def __set__(self, instance, value):
     # I want to know the *name* this value is being assigned to
     print 'descriptor.__set__ self=%r instance=%r value=%r' % (
       self, instance, value)

   def __delete__(self, instance):
     print 'descriptor.__delete__ self=%r instance=%r' % (
       self, instance)

class X(object):
   foo = descriptor()

x = X()
x.foo = "value"


I can obtain the name descriptor() was assigned to at the time the X class  
was defined, using a custom metaclass:


class Meta(type):
   def __new__(meta, name, bases, dict):
     for key,value in dict.iteritems():
       if isinstance(value, descriptor):
         value.name = key
     return type.__new__(meta, name, bases, dict)

class Y(object):
   __metaclass__ = Meta
   foo = descriptor()

y = Y()
print y.foo.name # prints 'foo'


This is good enough for me (assuming no one modifies the class after  
defining it, no two names refer to the same descriptor, no two classes  
share the same descriptor instance...). But I would like to use a more  
direct/robust approach, if available.

Any ideas?

-- 
Gabriel Genellina



From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Wed Jul 22 01:09:35 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Wed, 22 Jul 2009 01:09:35 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
Message-ID: <h467aq$mfg$1@news.eternal-september.org>

On 2009-07-21 19:06:02 -0400, Neil Hodgson 
<nyamatongwe+thunder at gmail.com> said:

>    Python uses native threads.

So it can be teh-slowness on all ur cores!

<http://shootout.alioth.debian.org/u64q/benchmark.php?test=nbody&lang=all>

The global interpreter lock doesn't help much either.

-- 
Raffael Cavallaro



From wolfgang at rohdewald.de  Wed Jul 22 01:24:21 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Wed, 22 Jul 2009 07:24:21 +0200
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <200907220724.21185.wolfgang@rohdewald.de>

On Wednesday 22 July 2009, Gabriel Genellina wrote:
> x = X()
> x.foo = "value"

del x.foo

-- 
Wolfgang


From wolfgang at rohdewald.de  Wed Jul 22 01:28:11 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Wed, 22 Jul 2009 07:28:11 +0200
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <200907220724.21185.wolfgang@rohdewald.de>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<200907220724.21185.wolfgang@rohdewald.de>
Message-ID: <200907220728.11536.wolfgang@rohdewald.de>

On Wednesday 22 July 2009, Wolfgang Rohdewald wrote:
> On Wednesday 22 July 2009, Gabriel Genellina wrote:
> > x = X()
> > x.foo = "value"
>
> del x.foo

sorry, was not yet quite awaken - I read "delete target name"
instead of "detect target name"

-- 
Wolfgang


From gagsl-py2 at yahoo.com.ar  Wed Jul 22 01:43:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 02:43:07 -0300
Subject: Regular exprssion for IRC messages
References: <e4de9e30907170959y4fcae9d3v8e26d9fd94e76f4f@mail.gmail.com>
Message-ID: <op.uxgfh5mex6zn5v@lepton.softlabbsas.com.ar>

En Fri, 17 Jul 2009 13:59:47 -0300, nohics nohics <nohics at gmail.com>  
escribi?:

> When an IRC client receive a messages, this message in in a special  
> format
> defined here: Message format in pseudo
> BNF<http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1>(
>
> I want to transforme the message format defined in the irc protocole in  
> the
> last link, to a regular expression to get the nickname, the username, the
> host, the commad, it's arguments if exist, and the message after ":"

You may want to use the pyparsing module instead of a monstruous and  
unmantainable regular expression:

http://pyparsing.wikispaces.com/

-- 
Gabriel Genellina



From jhinak.sen at gmail.com  Wed Jul 22 02:28:27 2009
From: jhinak.sen at gmail.com (jhinak sen)
Date: Wed, 22 Jul 2009 11:58:27 +0530
Subject: plotting graph from another file
Message-ID: <3d4ff96c0907212328q211801b4tc7a86986a9c35c25@mail.gmail.com>

hello..

i want to plot a distribution graph for following data:
*elements:               number of occurance:
   a                            2
   b                            4
   c                            1
   d                            9
   e                            3*

( this a simple version)

the data is in a file , say abc.txt

how can i call/import the text file and draw an appropriate distribution
graph in python  ?
can it be done using matplotlib ?

if yes , please give me the code for plotting the  importing the text file
and plotting the graph.

thanx

jhinak
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/7f93c95a/attachment-0001.html>

From hendrik at microcorp.co.za  Wed Jul 22 02:36:29 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 22 Jul 2009 08:36:29 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
Message-ID: <200907220836.30064.hendrik@microcorp.co.za>

On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
> On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
>
> wrote:
> > [snip] We
> > understand that lists are mutable and tuples are not, but we're a
> > little lost as to why the two were kept separate from the start. They
> > both perform a very similar job as far as we can tell.
>
> My guess is that it was probably for optimization reasons long ago.
> I've never heard a *good* reason why Python needs both.

The good reason is the immutability, which lets you use
a tuple as a dict key.  

- Hendrik


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 22 02:40:16 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 22 Jul 2009 06:40:16 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86skgr0yjn.fsf@gmail.com>
Message-ID: <pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au>

On Tue, 21 Jul 2009 00:39:24 +0200, Niels L. Ellegaard wrote:

> Phillip B Oldham <phillip.oldham at gmail.com> writes:
> 
>> We often find we need to do manipulations like the above without
>> changing the order of the original list, and languages like JS allow
>> this. We can't work out how to do this in python though, other than
>> duplicating the list, sorting, reversing, then discarding.

I think Phillip is confused if he thinks that other languages can sort a 
list without modifying or duplicating the original. If you don't 
duplicate the list, how can you sort it without modifying the original? 
The only difference is whether the language makes the duplicate for you, 
or expects you to do it yourself.


> If you just want a one-liner, and you don't care about speed you can do
> the following (but I don't think this is considered best practice)
> 
>>>> x = [2,1,3]
>>>> print list(sorted(x))

The call to list is redundant, as sorted() already creates a list.


But that's the wrong solution to the problem. The OP wants the largest 
(or smallest) item, which he expects to get by sorting, then grabbing the 
first element:

sorted(alist)[0]

That requires sorting the entire list, only to throw away everything 
except the first item. A better solution is to use min() and max(), 
neither of which sort the list, so they are much faster.



-- 
Steven


From steven at REMOVE.THIS.cybersource.com.au  Wed Jul 22 02:45:54 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 22 Jul 2009 06:45:54 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
Message-ID: <pan.2009.07.22.06.45.53@REMOVE.THIS.cybersource.com.au>

On Tue, 21 Jul 2009 06:49:59 -0700, Inky 788 wrote:

> On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com> wrote:
>> [snip] We
>> understand that lists are mutable and tuples are not, but we're a
>> little lost as to why the two were kept separate from the start. They
>> both perform a very similar job as far as we can tell.
> 
> My guess is that it was probably for optimization reasons long ago. I've
> never heard a *good* reason why Python needs both.

Suppose you could do this:

key = [1, 2]
adict = {key: 'x', [1, 1]: 'y'}

This would work as expected:

adict[ [1, 2] ]
=> returns 'x'

adict[ [1, 1] ]
=> returns 'y'

But what happens if you mutate the key?

key[1] = 0
adict[ [1, 2] ]
=> raises KeyError

Okay, that's bad. What's even worse is this:

key[1] = 1
adict[ [1, 1] ]
=> should it return 'x' or 'y'?


The solution is to disallow mutable objects like lists from being used as 
keys in dicts, and to allow immutable list-like tuples instead.



-- 
Steven


From clp2 at rebertia.com  Wed Jul 22 02:46:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Tue, 21 Jul 2009 23:46:13 -0700
Subject: plotting graph from another file
In-Reply-To: <3d4ff96c0907212328q211801b4tc7a86986a9c35c25@mail.gmail.com>
References: <3d4ff96c0907212328q211801b4tc7a86986a9c35c25@mail.gmail.com>
Message-ID: <50697b2c0907212346t3673b2a0rc5669bf7663bc4c6@mail.gmail.com>

On Tue, Jul 21, 2009 at 11:28 PM, jhinak sen<jhinak.sen at gmail.com> wrote:
> hello..
>
> i want to plot a distribution graph for following data:
> elements:?????????????? number of occurance:
> ?? a ?? ? ? ? ? ? ? ? ? ? ? ? ? 2
> ?? b??????????????????????????? 4
> ?? c??????????????????????????? 1
> ?? d??????????????????????????? 9
> ?? e??????????????????????????? 3
>
> ( this a simple version)
>
> the data is in a file , say abc.txt
>
> how can i call/import the text file and draw an appropriate distribution
> graph in python? ?
> can it be done using matplotlib ?
>
> if yes , please give me the code for plotting the? importing the text file
> and plotting the graph.

Given matplot's versatility, I would presume with high likelihood that
matplot could make such a chart.

However, the purpose of this mailinglist is *not* to do people's
job/work/homework for them for free.
I would suggest you first *attempt* coding a solution yourself.
If you run into trouble, read http://catb.org/~esr/faqs/smart-questions.html
Then ask a more specific question on the mailinglist.

Best of luck.

Regards,
Chris

From bearophileHUGS at lycos.com  Wed Jul 22 02:48:55 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 21 Jul 2009 23:48:55 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
Message-ID: <861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>

greg:
> Posting benchmark times for Pyrex or Cython is pretty
> meaningless without showing the exact code that was
> used, since times can vary enormously depending on
> how much you C-ify things.

Was this link, shown by William, not enough?
http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1

Bye,
bearophile


From greg at cosc.canterbury.ac.nz  Wed Jul 22 02:51:22 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Wed, 22 Jul 2009 18:51:22 +1200
Subject: clean way prepend an element to a numpy array
In-Reply-To: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
Message-ID: <7cnr5tF28183hU1@mid.individual.net>

bdb112 wrote:

> I saw this interest syntax on this site
> x[:0]=0
> 
> I guess that is cute, but could be confusing....(and doesn't work)

It does if you use an array of the appropriate
type on the right hand side:

   a[:0] = array('i', [0])

-- 
Greg


From walkraft at gmail.com  Wed Jul 22 02:59:34 2009
From: walkraft at gmail.com (casebash)
Date: Tue, 21 Jul 2009 23:59:34 -0700 (PDT)
Subject: Mutable Strings - Any libraries that offer this?
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<87r5wba9y1.fsf@benfinney.id.au>
	<02746e73$0$5185$c3e8da3@news.astraweb.com> 
	<87skgq8m7s.fsf@benfinney.id.au> <7cn4obF286u4kU1@mid.individual.net>
Message-ID: <cfcfdcf6-edca-42fe-a008-e1d55eed5f9e@g1g2000pra.googlegroups.com>

Thanks all for your advice. I'm not actually going to use the mutable
string right at the moment, but I thought I might in the future and I
was just curious if it existed. I suppose a list of characters is
close enough for most purposes.

On Jul 22, 10:28?am, greg <g... at cosc.canterbury.ac.nz> wrote:
> Ben Finney wrote:
> > My point was rather meant to imply that
> > subclassing the built-in (immutable)stringtypes was the best way to
> > usefully get all their functionality
>
> However, it would be difficult to do that without changing
> all C code that deals with strings, including that in extension
> modules.
>
> That's because the existingstringtype stores the characters
> in thestringobject itself. Amutablevariant would have to
> contain a pointer to a resizable memory block, and therefore
> couldn't be used as a drop-in replacement by existing C
> code that expects astring.
>
> --
> Greg



From timr at probo.com  Wed Jul 22 03:09:07 2009
From: timr at probo.com (Tim Roberts)
Date: Wed, 22 Jul 2009 00:09:07 -0700
Subject: win32api install problem
References: <d6b340d7-860f-4c77-8433-2b7671ba0a1d@k19g2000yqn.googlegroups.com>
Message-ID: <8led65544idaf3630nk21rjij030aj4s4k@4ax.com>

Gerry <gerard.blais at gmail.com> wrote:

>I'm running Python 2.6 under XP.
>
>I've installed Windows 32 extensions for Python 2.6 version 1.4
>(pywin32-214.win32-py2.6.exe).
>
>But If I try to import win32api, I get:
>
>  File "C:\python_projects\euler\driveletters.py", line 1, in <module>
>    import win32api
>ImportError: DLL load failed: The specified module could not be found.
>
>\Python26\Lib\site-packages has:
>
>03/23/2009  08:35 AM    <DIR>          win32
>07/20/2009  09:08 AM    <DIR>          win32com
>02/18/2009  01:21 PM    <DIR>          win32comext
>
>Can anyone offer a suggestion?

It is very unusual that those three directories should have different
creation dates.  Normally, all three would have the same date and time,
from whenever you ran the installer.

I would suggest that you go into Add and Remove Programs, uninstall
pywin32, and run the installer again.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.


From dtgeadamo at yahoo.com  Wed Jul 22 03:13:49 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Wed, 22 Jul 2009 00:13:49 -0700 (PDT)
Subject: Running a Python Service under the LocalService or NetworkService
	Account
References: <d76d8a76-99a3-4882-9db2-301eace73254@s15g2000yqs.googlegroups.com>
	<mailman.3425.1248098548.8015.python-list@python.org>
	<a10c5103-e6b3-4ab4-9455-a6b3d0f5a1d6@o15g2000yqm.googlegroups.com>
	<mailman.3429.1248106424.8015.python-list@python.org>
	<1d5e8a37-bc84-430f-93f4-685d9b073d63@c2g2000yqi.googlegroups.com>
	<2857576c-6695-431e-8d5f-62e9585d5fdf@q11g2000yqi.googlegroups.com> 
	<fZWdnWgkYJu7EPjXnZ2dnUVZ8mVi4p2d@bt.com>
	<3d45333b-3a3f-4672-a499-8bb4cafd4595@o7g2000yqb.googlegroups.com>
	<-vadnaHpJMoIjPvXnZ2dnUVZ8tli4p2d@bt.com>
Message-ID: <bb7706f8-8c83-4476-9bff-cebf3c8b9bd3@c1g2000yqi.googlegroups.com>

On Jul 21, 8:05?pm, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
wrote:
> David Adamo Jr. wrote:
> > On Jul 21, 10:40 am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
> > wrote:
> >> sightseer wrote:
>
> >> <knip>
>
> >>> Error Installing Service: Access is Denied. (5)
> >> <knip>
> >> Are you trying to do this on windows vista?
>
> >> --
> >> MPHhttp://blog.dcuktec.com
> >> 'If consumed, best digested with added seasoning to own preference.'
>
> > Yeah, I was trying to do it on Vista. Someone has just helped me out.
> > I had to deactivate User Account Control on Windows Vista...and now
> > everything is rosy. Thanks guys.
>
> No need to deactivate it, just right click on the command shell program
> and say run as administrator, than you can install the service via the
> command line.
>
> --
> MPHhttp://blog.dcuktec.com
> 'If consumed, best digested with added seasoning to own preference.'

Thanks MPH


From milesck at umich.edu  Wed Jul 22 03:21:06 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 22 Jul 2009 03:21:06 -0400
Subject: trouble with minidom
In-Reply-To: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
Message-ID: <A2032940-684F-4376-8CDA-6C1595F980DB@umich.edu>

On Jul 21, 2009, at 8:08 PM, Ronn Ross wrote:

> Hello I'm trying to read an xml file using minidome. The xml looks  
> like:
> <rootNode>
>    <project>
>       <name>myProj</name>
>       <path>/here/</path>
>    </project>
> </rootNode>
>
> My code looks like so:
> from xml.dom.minidom import parse
>
> dom = parse("myfile.xml")
>
> for node in dom.getElementsByTagName("project'):
>    print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,  
> node.childNodes[1])
>
> Unfortunately, it returns 'nodeValue as none. I'm trying to read the  
> value out of the node fir example name: myProj. I haven't found much  
> help in the documentation. Can someone point me in the right  
> direction?

Two issues:

In your example XML file, the first child node of the project Element  
is the Text node containing the whitespace between the <project> and  
<name> tags.  node.childNodes[0] will select that whitespace node.

The nodeValue of an Element is null (None).  In order to get the text  
contents of an element, you must get the nodeValue of the Text child  
node of the Element.

Like Gabriel, I would recommend using an XML library with a more  
concise API than the W3C DOM (I like lxml.objectify).  But if you  
stick with xml.dom, use the specification as a reference:

http://www.w3.org/TR/REC-DOM-Level-1/


From hv at tbz-pariv.de  Wed Jul 22 04:05:19 2009
From: hv at tbz-pariv.de (Thomas Guettler)
Date: Wed, 22 Jul 2009 10:05:19 +0200
Subject: Workflow Libraries (DB vs Code)
In-Reply-To: <7cm6kmF26g9srU1@mid.uni-berlin.de>
References: <7cm1ifF28jmnhU1@mid.individual.net>
	<7cm6kmF26g9srU1@mid.uni-berlin.de>
Message-ID: <7cnvi0F28qk9aU1@mid.individual.net>

Diez B. Roggisch schrieb:
> Thomas Guettler wrote:
> 
>> Hi,
>>
>> I need to write some simple workflows with web interface.
>>
>> For the web stuff I will use django, but I am not sure how
>> to do the workflow part.
> 
> Did you consider using OpenERP? It comes with a web-frontend
> (TG1.0.8-based), but also offers a XMLRPC-server to connect to, so using it
> from within django shouldn't be any difficult.
> 
> Workflow-definitions are stored in the DB, and can be generated visually,
> not sure if they have to though.

Thank you for this hint. OpenERP seems well done.

But the licence is GPL and the dependency is too big. But I will have a look
at how they did it.

  Thomas


-- 
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de


From joncle at googlemail.com  Wed Jul 22 04:21:49 2009
From: joncle at googlemail.com (Jon Clements)
Date: Wed, 22 Jul 2009 01:21:49 -0700 (PDT)
Subject: Regular exprssion for IRC messages
References: <e4de9e30907170959y4fcae9d3v8e26d9fd94e76f4f@mail.gmail.com> 
	<mailman.3509.1248241400.8015.python-list@python.org>
Message-ID: <4e59a9a3-f565-4042-9016-5192b8ff8247@c29g2000yqd.googlegroups.com>

On 22 July, 06:43, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> En Fri, 17 Jul 2009 13:59:47 -0300, nohics nohics <noh... at gmail.com> ?
> escribi?:
>
> > When an IRC client receive a messages, this message in in a special ?
> > format
> > defined here: Message format in pseudo
> > BNF<http://www.irchelp.org/irchelp/rfc/chapter2.html#c2_3_1>(
>
> > I want to transforme the message format defined in the irc protocole in ?
> > the
> > last link, to a regular expression to get the nickname, the username, the
> > host, the commad, it's arguments if exist, and the message after ":"
>
> You may want to use the pyparsing module instead of a monstruous and ?
> unmantainable regular expression:
>
> http://pyparsing.wikispaces.com/
>
> --
> Gabriel Genellina

Alternatively, if IIRC, the twisted framework has an IRC client, which
automatically parses server messages.


From dtgeadamo at yahoo.com  Wed Jul 22 04:27:52 2009
From: dtgeadamo at yahoo.com (David Adamo Jr.)
Date: Wed, 22 Jul 2009 01:27:52 -0700 (PDT)
Subject: Ideas for problem with chat server application!
Message-ID: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>

I developed a chat application with an attendant chat server.
Everything is working fine. The issue now is the fact that whenever
the chat server goes down (for instance, the server system shuts down
as a result of power failure or some other problem), by the time the
server system come back on, the chat server would have to be restarted
manually.

I believe (and I know) it is more appropriate for the chat server
application to restart itself when the computer comes back on (and of
course regardless of who is logged in and of course, even before
anyone logs in). I have a batch file that executes the chat server. My
attempt was to create a windows service that start automatically and
runs this batch file using a Network Service account on the server
system. Although, I'm having a hard time with this (temporarily), I
would love to ask if there are any alternatives to using a windows
service. Suggestions are highly appreciated.


From joncle at googlemail.com  Wed Jul 22 04:31:13 2009
From: joncle at googlemail.com (Jon Clements)
Date: Wed, 22 Jul 2009 01:31:13 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <mailman.3504.1248238988.8015.python-list@python.org>
Message-ID: <3cb5f960-16f7-4fc6-841f-d0706f0e1d0a@s31g2000yqs.googlegroups.com>

On 22 July, 06:02, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> I have a class attribute 'foo' which is a data descriptor. I create an ?
> instance of such class. When I say instance.foo = value, the descriptor ?
> __set__ method is called. Is there any way to obtain the name being ?
> assigned to? ('foo' in this example). That is, I want to know the target ?
> name for the assignment that triggered the __set__ method call.
>
> class descriptor(object):
> ? ?def __get__(self, instance, owner):
> ? ? ?print 'descriptor.__get__ self=%r instance=%r owner=%r' % (
> ? ? ? ?self, instance, owner)
> ? ? ?return self
>
> ? ?def __set__(self, instance, value):
> ? ? ?# I want to know the *name* this value is being assigned to
> ? ? ?print 'descriptor.__set__ self=%r instance=%r value=%r' % (
> ? ? ? ?self, instance, value)
>
> ? ?def __delete__(self, instance):
> ? ? ?print 'descriptor.__delete__ self=%r instance=%r' % (
> ? ? ? ?self, instance)
>
> class X(object):
> ? ?foo = descriptor()
>
> x = X()
> x.foo = "value"
>
> I can obtain the name descriptor() was assigned to at the time the X class ?
> was defined, using a custom metaclass:
>
> class Meta(type):
> ? ?def __new__(meta, name, bases, dict):
> ? ? ?for key,value in dict.iteritems():
> ? ? ? ?if isinstance(value, descriptor):
> ? ? ? ? ?value.name = key
> ? ? ?return type.__new__(meta, name, bases, dict)
>
> class Y(object):
> ? ?__metaclass__ = Meta
> ? ?foo = descriptor()
>
> y = Y()
> print y.foo.name # prints 'foo'
>
> This is good enough for me (assuming no one modifies the class after ?
> defining it, no two names refer to the same descriptor, no two classes ?
> share the same descriptor instance...). But I would like to use a more ?
> direct/robust approach, if available.
>
> Any ideas?
>
> --
> Gabriel Genellina

>>> class Test:
	def __setattr__(self, what, value):
		print what, value


>>> t = Test()
>>> t.foo = 'x'
foo x

Is that what you're after?

Jon.


From phillip.oldham at gmail.com  Wed Jul 22 05:27:56 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Wed, 22 Jul 2009 02:27:56 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
Message-ID: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>

I understand that there are a number of MapReduce frameworks/tools
that play nicely with Python (Disco, Dumbo/Hadoop), however these have
"large" dependencies (Erlang/Java). Are there any MapReduce frameworks/
tools which are either pure-Python, or play nicely with Python but
don't require the Java/Erlang runtime environments?


From user at example.net  Wed Jul 22 06:03:44 2009
From: user at example.net (superpollo)
Date: Wed, 22 Jul 2009 12:03:44 +0200
Subject: binary literal
Message-ID: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>

hello clp.

i can insert a hex value for a character literal in a string:

 >>> stuff = "\x45"
 >>> print stuff
E
 >>>

can i do something like the above, but using a *binary* number? (e.g. 
00101101 instead of 45) ?

bye


From pmarti at warp.es  Wed Jul 22 06:24:22 2009
From: pmarti at warp.es (=?ISO-8859-1?Q?Pablo_Mart=ED_Gamboa?=)
Date: Wed, 22 Jul 2009 12:24:22 +0200
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <53a2f8770907220324m445c3004s9c844176255eaf46@mail.gmail.com>

2009/7/22 superpollo <user at example.net>

> hello clp.
>
> i can insert a hex value for a character literal in a string:
>
> >>> stuff = "\x45"
> >>> print stuff
> E
> >>>
>
> can i do something like the above, but using a *binary* number? (e.g.
> 00101101 instead of 45) ?


(Python 3)

 >>> bin(45)
'0b101101'
>>> int(_, 2)
45

-- 
Pablo Mart?
http://www.linkedin.com/in/pmarti || http://www.warp.es
python -c "print '706d6172746940776172702e6573'.decode('hex')"
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/67261312/attachment-0001.html>

From eckhardt at satorlaser.com  Wed Jul 22 06:25:32 2009
From: eckhardt at satorlaser.com (Ulrich Eckhardt)
Date: Wed, 22 Jul 2009 12:25:32 +0200
Subject: binary literal
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <s16jj6-c6o.ln1@satorlaser.homedns.org>

superpollo wrote:
> i can insert a hex value for a character literal in a string:
> 
>  >>> stuff = "\x45"
>  >>> print stuff
> E
>  >>>
> 
> can i do something like the above, but using a *binary* number? (e.g.
> 00101101 instead of 45) ?

There are binary number literals since 2.6 and there is the chr() function.

 >>> print chr(0b1000101)
E

Uli

-- 
Sator Laser GmbH
Gesch?ftsf?hrer: Thorsten F?cking, Amtsgericht Hamburg HR B62 932



From theajodharan.vfx at gmail.com  Wed Jul 22 06:29:59 2009
From: theajodharan.vfx at gmail.com (TNR)
Date: Wed, 22 Jul 2009 11:29:59 +0100
Subject: Python
In-Reply-To: <6281cf33-8ab6-4ff6-a2c5-a9fa1e66d368@m7g2000prd.googlegroups.com>
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
	<00e687679e63af535bea6a4046f1df08@preisshare.net>
	<mailman.3503.1248229122.8015.python-list@python.org>
	<6281cf33-8ab6-4ff6-a2c5-a9fa1e66d368@m7g2000prd.googlegroups.com>
Message-ID: <dc8c68420907220329h315689d0n8f66c3c82cdac7dd@mail.gmail.com>

Hi,

Check the below links..
http://www.tutorialspoint.com/python/
http://www.java2s.com/Tutorial/Python/CatalogPython.htm

Hope that helps.

Cheers
-theajo



On Wed, Jul 22, 2009 at 5:42 AM, Prateek <prateekkakirwar at gmail.com> wrote:

> Chk dis out ...
>
> http://www.swaroopch.com/notes/Python
>
> It's gr8 guide for beginners
>
> Cheers!!!
> Prateek
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/63bd5dc3/attachment-0001.html>

From sjmachin at lexicon.net  Wed Jul 22 06:34:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 22 Jul 2009 10:34:16 +0000 (UTC)
Subject: Fast reading and unpacking of binary data (struct module)
References: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>
Message-ID: <loom.20090722T100951-701@post.gmane.org>

Daniel Platz <mail.to.daniel.platz <at> googlemail.com> writes:

> 
> Hi,
> 
> I have a Python newbie question about reading data from a binary file.
> I have an huge binary file from an external program.

Please translate "huge" into Mb. Also, how much free real memory do you have?

> I want to read
> and process the data in this file in a reasonable time. It turns out
> that the reading of the data itself and the processing do not need
> most of the time. However, when using the read(bytes) method Python
> returns a string representing the binary information in hex.

"In hex" is not part of the string's nature. If you look at it through
hexadecimal/decimal/octal/binary spectacles, you'll see respectively
hex/decimal/octal/binary.

> This
> string I have to "cast/translate" into a number (in my case a signed
> short). For this I am using the method struct.unpack from the struct
> module. This unpacking part of the program takes by far the most time.
> Is there a way to speed this up or to do it the unpacking more
> cleverly than with the struct module?

Are you reading the file (a) two bytes at a time (b) several Kb at a time (c)
whole file?

Are you unpacking it ... [same options as above but the two answers may differ]?

What are you planning to do with this large list/array? The array option that
Gabriel mentioned should be fastest to load, and take up least memory, but
working with the elements will require making int objects out of the shorts (and
the reverse if you are updating the array).

Is numpy (http://numpy.scipy.org/) a possibility?

Cheers,

John



From drunkard at thepub.co.za  Wed Jul 22 07:05:31 2009
From: drunkard at thepub.co.za (Mark du Preez)
Date: Wed, 22 Jul 2009 13:05:31 +0200
Subject: Documentation Problems
Message-ID: <h46rpv$lm5$1@adenine.netfront.net>

Hi

Can anyone tell me where to go to suggest changes to the Python 
documentation?

Thanks. 




From ndbecker2 at gmail.com  Wed Jul 22 07:12:07 2009
From: ndbecker2 at gmail.com (Neal Becker)
Date: Wed, 22 Jul 2009 07:12:07 -0400
Subject: Fast reading and unpacking of binary data (struct module)
References: <76f9e536-dffd-4fd8-8fdc-7231603813b5@a26g2000yqn.googlegroups.com>
Message-ID: <h46s68$pnr$1@ger.gmane.org>

Daniel Platz wrote:

> Hi,
> 
> I have a Python newbie question about reading data from a binary file.
> I have an huge binary file from an external program. I want to read
> and process the data in this file in a reasonable time. It turns out
> that the reading of the data itself and the processing do not need
> most of the time. However, when using the read(bytes) method Python
> returns a string representing the binary information in hex. This
> string I have to "cast/translate" into a number (in my case a signed
> short). For this I am using the method struct.unpack from the struct
> module. This unpacking part of the program takes by far the most time.
> Is there a way to speed this up or to do it the unpacking more
> cleverly than with the struct module?
> 
> Thanks in advance.
> 
> With kind regards,
> 
> Daniel

Consider mmap
Consider numpy
Consider numpy+mmap




From mail at timgolden.me.uk  Wed Jul 22 07:15:22 2009
From: mail at timgolden.me.uk (Tim Golden)
Date: Wed, 22 Jul 2009 12:15:22 +0100
Subject: Documentation Problems
In-Reply-To: <h46rpv$lm5$1@adenine.netfront.net>
References: <h46rpv$lm5$1@adenine.netfront.net>
Message-ID: <4A66F4CA.2070506@timgolden.me.uk>

Mark du Preez wrote:
> Hi
> 
> Can anyone tell me where to go to suggest changes to the Python 
> documentation?

Drop an entry in the tracker:

  http://bugs.python.org

Patches are always welcome, or at least suggested wording rather
than vague "I don't think it should say that" -- although that's
better than nothing!

TJG


From nipunreddevil at gmail.com  Wed Jul 22 07:15:33 2009
From: nipunreddevil at gmail.com (nipun batra)
Date: Wed, 22 Jul 2009 16:45:33 +0530
Subject: GTK+ ques
Message-ID: <1e61b3260907220415g6edb24sb7fe07c83fe346c8@mail.gmail.com>

I need to develop a GUI preferably in GTK using c or PYGTK.I have little
idea about Python.
Following are requiremnts of the application:
should be GUI
Sould be real time
Should interface serial port
should display moving maps,like google earth
It is basically for Ground control station of a UAV.
How would Python+Pygtk combo work?
is python slower than c/c++ ,if then by how much?
any suggestions for the applcation?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/0f115d13/attachment-0001.html>

From deets at nospam.web.de  Wed Jul 22 07:15:45 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 22 Jul 2009 13:15:45 +0200
Subject: Documentation Problems
References: <h46rpv$lm5$1@adenine.netfront.net>
Message-ID: <7coan1F28i1q2U1@mid.uni-berlin.de>

Mark du Preez wrote:

> Hi
> 
> Can anyone tell me where to go to suggest changes to the Python
> documentation?
> 
> Thanks.

http://docs.python.org/ has a "bugs"-section that leads to

http://docs.python.org/bugs.html

You can file doc-bugs in the tracker, and check if they are already fixed in
the dev-docs.

Diez


From wilk at flibuste.net  Wed Jul 22 07:38:08 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 11:38:08 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
Message-ID: <4a66fa20$0$11368$426a74cc@news.free.fr>

I updated the script (python, c and java) with your unrolled version 
+ somes litle thinks.

I also tried with python3.1, unladen Q2, ironpython1.1.1

Unfortunately it doesn't work more with shedskin, i'll see on the 
shedskin group...

c 1.85s
gcj 2.15s
java 2.8s
python2.5 + psyco 3.1s
unladen-2009Q2 145s (2m45)
python2.5 254s (4m14s)
python3.1 300s (5m)
ironpython1.1.1 680s (11m20)


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From wfluro at gmail.com  Wed Jul 22 07:38:43 2009
From: wfluro at gmail.com (ulf)
Date: Wed, 22 Jul 2009 04:38:43 -0700 (PDT)
Subject: Python ctypes on win64
Message-ID: <f415d834-b2ac-4036-afb1-a12c79480eb4@i6g2000yqj.googlegroups.com>

Hi,

Does anybody know if python includes a win64 version of ctypes?

According to the documentation it should be included - at least
there's no special remarks for win64, and I haven't found any recent
notes saying that it shouldn't work on win64. Yet it looks like both
the installer from Python.org and from ActiveState.com have disabled
it.

regards

/ulfw


From duncan.booth at invalid.invalid  Wed Jul 22 07:55:13 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 22 Jul 2009 11:55:13 GMT
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86skgr0yjn.fsf@gmail.com>
	<pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au>
Message-ID: <Xns9C5082EB1B123duncanbooth@127.0.0.1>

Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> wrote:

> But that's the wrong solution to the problem. The OP wants the largest
> (or smallest) item, which he expects to get by sorting, then grabbing
> the first element:
> 
> sorted(alist)[0]
> 
> That requires sorting the entire list, only to throw away everything 
> except the first item. A better solution is to use min() and max(), 
> neither of which sort the list, so they are much faster.
> 
And if they want the n smallest or largest items (where n is significantly 
less than the length of the list[*]) they might consider using 
heapq.nsmallest() and heapq.nlargest()

I find it interesting that the heapq functions tell you in the 
documentation that they aren't suitable for use where n==1 or where n is 
near the total size of the sequence whereas random.sample() chooses what it 
thinks is the best algorithm based on the input. At the very least I would 
have thought the heapq functions could check for n==1 and call min/max when 
it is.

[*] Some quick playing with timeit seems to indicate that with a list of 
200 integers nsmallest is fastest (by a very small margin) when n==2 and 
n==3 but is beaten by sorted[:n] when n==4, so I guess you need a 
reasonably long list to make it worth not sorting it: with list of 20,000 
integers it isn't worth sorting unless you want more than about 700 items.

-- 
Duncan Booth http://kupuguy.blogspot.com


From deets at nospam.web.de  Wed Jul 22 07:55:29 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 22 Jul 2009 13:55:29 +0200
Subject: List insertion cost
References: <mailman.3481.1248204184.8015.python-list@python.org>
Message-ID: <7cod1hF28nhhlU1@mid.uni-berlin.de>

Lucas P Melo wrote:

> Hello,
> I would like to know how much it costs to insert an element into a list
> using this operation:
> a[2:2] = [ 1 ]
> i. e, what is the complexity of the operation above (given that len(a) =
> n)?

O(n) I'd say. You need to copy nearly the whole list, and sometimes
re-allocate it's storage (they are internally stored as arrays of object
references)

Diez


From jeanmichel at sequans.com  Wed Jul 22 08:16:19 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 22 Jul 2009 14:16:19 +0200
Subject: doted filenames in import statements
In-Reply-To: <m2prbtllen.fsf@cs.uu.nl>
References: <mailman.3488.1248212574.8015.python-list@python.org>
	<m2prbtllen.fsf@cs.uu.nl>
Message-ID: <4A670313.8040204@sequans.com>

Piet van Oostrum wrote:
>
> [snip]
>
>> JP> file = "/home/dsp/4.6.0.0/test.py"
>> JP> test = __import__(file)
>> JP> => no module name blalalal found.
>>     
>
>   
>> JP> Any suggestion ? I tried multiple escape technics without any success.
>>     
>
> Rightly so.
>
> I think the best would be to add the directory to sys.path 
> sys.path.add('/home/dsp/4.6.0.0')
> and then
> __import__('test', ... ) 
>   

I see. My problem is that a have to import 2 different files having de 
same name. In the same name space I have 2 objects from 2 different 
software branches, let's say 4.6.0 and 4.6.1.
The first object shall import 4.6.0/orb.py and the second one 4.6.1/orb.py.

If I add 4.6.1 to sys.path, the import statement will look like:
self._orb = __import__('orb')
The problem is, python wil assume orb is already imported and will 
assign the module from the 4.6.0 branch to my 4.6.1 object.

Do I have to mess up with sys.modules keys to make python import the 
correct file ? Is there a standard/proper way to do that ?

JM


From ryniek90 at gmail.com  Wed Jul 22 08:29:20 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 22 Jul 2009 14:29:20 +0200
Subject: Changing the private variables content
In-Reply-To: <mailman.13231.1248210896.8014.python-list@python.org>
References: <mailman.13231.1248210896.8014.python-list@python.org>
Message-ID: <4A670620.1090501@gmail.com>

>
> ------------------------------------------------------------------------
>
> Temat:
> Re: Changing the private variables content
> Od:
> Gary Herron <gherron at islandtraining.com>
> Data:
> Tue, 21 Jul 2009 14:14:44 -0700
> Do:
> Ryniek90 <ryniek90 at gmail.com>
>
> Do:
> Ryniek90 <ryniek90 at gmail.com>
> Kopia:
> python-list at python.org
>
>
> Ryniek90 wrote:
>> Hi.
>> I'm writing some class, and decided to use inside private method and 
>> some private variables. While with method i haven't got any problem's 
>> with variables i have.
>> Maybe some example.
>> A class with private method and private variable:
>>
>> "
>> >>> class Secret(object):
>>    #
>>    def __init__(self):
>>        self._number = 1
>>    #
>>    def _secret(self):
>>        print self._number
>>    def showit(self):
>>        print "Secret number is:\n"
>>        self._secret()
>>
>> >>> sec = Secret()
>> >>> sec.showit()
>> Secret number is:
>>
>> 1
>> >>> sec._number
>> 1
>> >>> sec._number = 2
>> >>> sec._number
>> 2
>> >>> sec._number += 3
>> >>> sec._number
>> 5
>> >>>
>> "
>>
>> As You can see, i made class with private method and private variable 
>> inside __init__ constructor. I've changed also the variable value, 
>> but outside class.
>> I've got problem with changing some variable value _inside__my_ 
>> class, which i'm writing.
>
> Not sure this is what you are asking, but a method (which is how I 
> interpret "_inside__my_ class") changes the value by normal assignment 
> like this:
>
> class Secret(object):
>  ...
>  def SetNumber(self,value):
>    self._number = value
>
> Is that what you were asking?
>
>
> Gary Herron
>
>
>
>> I've searched over google, some tuts with topics about operations on 
>> private variables, but didn't found anything - only how to make them, 
>> but no how to assign new objects/override them with new content (and 
>> other advanced and helpful options).
>>
>> If someone could help me, it would be great.
>>
>> Thanks.
>
>


Thanks for hint, but looks like i can't do what i want.

Maybe i show You my class:

"

class ModPrint(object):
   
    u"""
    This will be the doc.
    """
   
    def __init__(self):
       
        #Assign the Python installation directory - sys.exec_prefix - to 
variable
        self._default_search_path=sys.exec_prefix
        self._chosen_module = ''
        self._user_search_path = ''
        self._this_module = ''
       
    def _SetVar(self, attr, val):
        self.attr = val   
       
    def _search_for_module(self, *args):
       
        """Private method which walks through default Python 
installation directories, and search for prefered module."""
       
        #walking thru all directories available in path '_user_search_path'
        for root, dirs, files in os.walk(self._user_search_path):
            for f in files:
               
                #if found file 'f' is THAT module,
                #full path to THAT file is assigned to variable
                if f == ("%s.py" % self._chosen_module):
                    self._SetVar(self._this_module, os.path.join(root, f))
                   
                   
    def print_module(self, _chosen_module='', _user_search_path='', 
_default_search_path=sys.exec_prefix,):
       
        """Reads module chosen by user, and returns full content of this 
module, as it is."""
       
       
        #if custom search path hasn't been assigned,
        #default path is being assigned as custom path
        if self._user_search_path == '':
            self._user_search_path = self._default_search_path
           
        #using private method '_search_for_module' with 'self.' preffix
        #to search for prefered module
        self._search_for_module(_chosen_module, _user_search_path)
       
        #opening prefered module with read-only binary mode
        #and assigning it to 'module_open' variable
        module_open = open(self._this_module, 'rb')
       
        #reading this file and assigning it to variable
        module_text = module_open.read()
       
        #closing read file; the read content is still available
        #it's stored in variable 'module_text'
        module_open.close()
       
        #returning the read content
        return module_text

"

When i use this class in Python IDLE, i've got this error:
"
 >>> mod = ModPrint()
 >>> import socket
 >>> mod.print_module('socket')

Traceback (most recent call last):
  File "<pyshell#60>", line 1, in <module>
    mod.print_module('socket')
  File "<pyshell#57>", line 48, in print_module
    module_open = open(self._this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

As You can see, i can't assign the new value "os.path.join(root, f)" to 
the 'self._this_module variable'.
So for sure i've made some mistake in method:

"
def _SetVar(self, attr, val):
        self.attr = val   
"
When i've changed private variables to normal, stored in class (in 
__init__ method), it was the same situation - i couldn't change this 
variable value.

"
 >>> mod = ModPrint()
 >>> mod.print_module('os')

Traceback (most recent call last):
  File "<pyshell#72>", line 1, in <module>
    mod.print_module('os')
  File "<pyshell#64>", line 48, in print_module
    module_open = open(self.this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

Thanks i someone could help me, give some hint.


From contact at xavierho.com  Wed Jul 22 08:45:37 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 22:45:37 +1000
Subject: Changing the private variables content
In-Reply-To: <4A670620.1090501@gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
Message-ID: <2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>

On Wed, Jul 22, 2009 at 10:29 PM, Ryniek90 <ryniek90 at gmail.com> wrote:

> Thanks for hint, but looks like i can't do what i want.


That's because

>
>         def _SetVar(self, attr, val):
>       self.attr = val


 doesn't work as you might think. However, I tried to replace it with:

val('self.' + attr + '=\'' + val + '\'')

and it gives me a syntax error!

  File "test.py", line 7, in _setVar
    eval('self.' + attr + '=\'' + val + '\'')
  File "<string>", line 1
    self.var='Mrra'
            ^
SyntaxError: invalid syntax

So, uh, I'm wondering if this is a bug. And also the solution to his
problem.

Good luck. Any ideas appreciated.

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/44ef6fd3/attachment-0001.html>

From python-url at phaseit.net  Wed Jul 22 08:48:25 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Wed, 22 Jul 2009 12:48:25 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul 22)
Message-ID: <h471qp$dfq$1@lairds.us>

QOTW:  "If programming is symbol manipulation, then you should remember that
the user interface is also symbol manipulation, and it is a MUCH harder
problem than databases, sorting, searching, and all the other problems you
learn about in academia. The user interface has to communicate over a rich
but noisy channel using multiple under-specified protocols to a couple of
pounds of meat which processes information using buggy heuristics evolved
over millions of years to find the ripe fruit, avoid being eaten, and have
sex. If you think getting XML was hard, that's *nothing* compared to user
interfaces.

The fact that even bad UIs work at all is a credit to the heuristics, bugs
and all, in the meat." - Steven D'Aprano
     http://groups.google.com/group/comp.lang.python/msg/8c65eacbd76e79cf


    Invoke the same method over every object in a collection:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8fd293a9b39c8733/
    
    There is no 'xor' boolean operator, why? What should be its outcome?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/16eec722310e75e8/
    
    A thread-safe method to create unique identifiers (not necesarily
    increasing integers):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/dfe22a6446c057df/
    
    Tim Chase tells us three ways to turn standard output into unbuffered mode:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/a65f71444bd4bb53/
    
    How to receive data of unknown length using sockets:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/9e4a9f8b6e83320/
    
    Override a method, but keeping the inherited docstring:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/1e4075ba10dcbdd9/
    
    Limiting the execution time of a code fragment:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/734054de170e2904/
    
    Sharing a big object between processes using the multiprocessing module:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/833d4988b7af6353/
    
    Why aren't OrderedDicts [3.1] comparable using <, >, <=, >=?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/c3c6f4fe7b6d487d/
    
    So many ways to call a function - why is that? Beginners get confused:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3fd57f5ee4850530/
    
    The reasons to choose your favorite programming language (Python, I
    presume!):
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/5d87008e328efcf9/
    
    Tuples, lists, their differences and motivation:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/cb0cf56c52321ccc/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From contact at xavierho.com  Wed Jul 22 08:52:45 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 22:52:45 +1000
Subject: Changing the private variables content
In-Reply-To: <2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
	<2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>
Message-ID: <2d56febf0907220552q6a96107ds7b60ba46ac82ef6a@mail.gmail.com>

>
> val('self.' + attr + '=\'' + val + '\'')
>

Obviously that was eval, not val. Also it doesn't work without the escaped
single quotes, either.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/5a4fa4b4/attachment-0001.html>

From mark.dufour at gmail.com  Wed Jul 22 08:55:57 2009
From: mark.dufour at gmail.com (srepmub)
Date: Wed, 22 Jul 2009 05:55:57 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
Message-ID: <d6f06288-4250-4065-bdf1-a880de3b875a@y7g2000yqa.googlegroups.com>


please send any program that doesn't work with shedskin (it still is
experimental after all) to me, or create an issue at
shedskin.googlecode.com, and I will have a look at the problem.


thanks,
mark.


From wilk at flibuste.net  Wed Jul 22 08:59:37 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 12:59:37 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
	<d6f06288-4250-4065-bdf1-a880de3b875a@y7g2000yqa.googlegroups.com>
Message-ID: <4a670d39$0$11286$426a74cc@news.free.fr>

On 22-07-2009, srepmub wrote:
>
> please send any program that doesn't work with shedskin (it still is
> experimental after all) to me, or create an issue at
> shedskin.googlecode.com, and I will have a look at the problem.

I did it, on the discussion group
http://groups.google.com/group/shedskin-discuss/browse_thread/thread/c1f47a7c21897b44

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From disappearedng at gmail.com  Wed Jul 22 09:04:18 2009
From: disappearedng at gmail.com (disappearedng)
Date: Wed, 22 Jul 2009 21:04:18 +0800
Subject: Finding all cycles within an undirected graph
Message-ID: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>

Hey everyone,
I am interested to find out all the cycles within an undirected graph.
I don't have a particular implementation of nodes and vertices yet, so
would someone kindly point out a good graph library for this ( I
looked at pygraph and python-graph, but not really satisfied ), in
addition to good algorithm for solving this issue.


From contact at xavierho.com  Wed Jul 22 09:06:22 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 23:06:22 +1000
Subject: Changing the private variables content
In-Reply-To: <2d56febf0907220552q6a96107ds7b60ba46ac82ef6a@mail.gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
	<2d56febf0907220545o25077f01u4682bd35b922d22a@mail.gmail.com>
	<2d56febf0907220552q6a96107ds7b60ba46ac82ef6a@mail.gmail.com>
Message-ID: <2d56febf0907220606q19e343f2mdd276d4e734ee048@mail.gmail.com>

Got it:

exec('self.' + attr + '=\'' + val + '\'')

That worked. I think it'll do what you want now ;)

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/12f34301/attachment-0001.html>

From davea at ieee.org  Wed Jul 22 09:11:26 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 09:11:26 -0400
Subject: Multiple versions of python
In-Reply-To: <98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>	<mailman.3465.1248186000.8015.python-list@python.org>
	<98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
Message-ID: <4A670FFE.80405@ieee.org>

CCW wrote:
> On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
>   
>> ChrisW wrote:
>>     
>>> Hi,
>>>       
>>> I have installed 2 versions of python on my Windows XP computer - I
>>> originally had 3.0.1, but then found that the MySQL module only
>>> supported 2.*, so I've now installed that.  I have found that if I
>>> change the Windows Environment Variable path, then I can change the
>>> version of python called when I type 'python' into a command line.
>>> However, I'd like to be able to choose which version I use.  I know
>>> that if I change C:\Python26\python.exe to
>>> C:\Python26\python2.exe and C:\Python30\python.exe to C:
>>> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
>>> the correct interpreter.  However, is it safe just to rename the
>>> executable files? Is there a more elegant way to achieve the same
>>> task?
>>>       
>>> Thanks,
>>> Chris
>>>       
>> The elegant way is to have a batch directory on your PATH ( I use  
>> m:\t\bat )  and put your *.bat files there.   I do NOT put any python
>> installations on the PATH.
>>
>> For example, I have a batch file called:     m:\t\bat\python26.bat
>>
>> c:\progfiles\python26\python.exe %*
>>
>> The %* syntax means pass all arguments through to the program.
>>
>> Once it all works, you can add an "@" in front of the c:   in order to
>> suppress echoing the command.  At that point, it'll look and work the
>> same way as what you did, but without modifying anything in the install
>> directory.    (You may want  python26.bat, pythonw26.bat, python31.bat
>> and pythonw31.bat)
>>
>> The other thing you may want to do in a batch file is to change the file
>> associations so that you can run the .py file directly, without typing
>> "python" or "pythonw" in front of it.
>>
>> The relevant Windows commands are:     assoc and ftype      And on a
>> related note, you may want to edit the PATHEXT environment variable, to
>> add .PY and .PYW
>>     
>
> Thanks for this - this way made a bit more sense to me.  I've now got
> C:\commands with the 4 .bat files in, and C:\commands in my path.  It
> all seems to work :) I think I've missed the point of the @ though -
> it doesn't seem to make any difference..
>
> I'm also a bit confused with the associations - since I've got python
> 2.6 and 3.1, surely the command I type (python26 or python31) is the
> only way to force a script to be run using a specific interpreter at
> runtime without having to change the .bat file every time I want to
> run a script using 3.1 instead of 2.6?
>
>   
The @ symbol was used in older versions of CMD and COMMAND to suppress 
echoing of the command line.  I think if you're using XP or later, it 
doesn't matter.

As for file associations, I don't know just what you already know 
about.  When you type    data.doc    at a command line, the system looks 
for the data file, then if it's found, it looks up the program 
associated with that extension.  On my machine, that's a particular 
version of Word for Windows.  Similarly, if I type    digest.py   and 
I'm in the directory containing that file, the system looks up my 
associations, and runs Python 2.6 on that file.  If I wanted it to run 
Python 3.1 on that file, I'd have to change the associations, temporarily.

So, first approximation, it's a way to avoid having to type PYTHON each 
time I want to run a script, as long as I don't need any other arguments 
on the (implied) command line.  Further, the system will then look for 
digest.py everywhere on the PATH, so I don't even have to be in the same 
directory.  And that means I can be in the data directory that digest.py 
is going to work on.  Effectively, it raises digest.py to feeling like 
an executable, for most purposes.  In fact, I put all my scripts in a 
directory, along with other simple executables.   I use  m:\t\bin  for 
that purpose.

These associations (to .py and .pyw) are established by the installer 
program for Python.  But when you had multiple installs, you could 
choose whether the second one installed overrides the first.  My point 
is that if you need to change them back and forth, you could use  assoc 
and ftype to do it.

On my system:

M:\LabOrders>assoc .py
.py=Python.File

M:\LabOrders>ftype Python.File
Python.File="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*

M:\LabOrders>


So my .py files are associated with the 2.6.2 version of ActivePython 
installation.   Note the similarity of the ftype to your python26.bat file?

One more little trick is that I could just type   digest    instead 
of    digest.py,   if I have added the .py and .pyw extensions to my   
PATHEXT environment variable.    So my PATHEXT looks like:
   PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.PY;.PYW



Note that the association changes made by  assoc and ftype are global.  
They apply to all cmd.exe windows, even those already running, and they 
survive a reboot.  But when you set environment variables like PATHEXT,  
you can choose to do it in a single window (with SET), or globally 
(using control-panel).

If I found myself switching often, I'd make separate ftype entries for 
each interpreter, something like
  Python.File26="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*
  Python.File31="C:\PROGFI~1\.....      

and just change assoc .py  to point at the one I needed today.

As it is, I'm content leaving the associations pointing at 2.6, and 
explicitly entering PYTHON31 in front of any script name I want to run 
on that interpreter.

DaveA



From python at mrabarnett.plus.com  Wed Jul 22 09:12:18 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 22 Jul 2009 14:12:18 +0100
Subject: Changing the private variables content
In-Reply-To: <4A670620.1090501@gmail.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com>
Message-ID: <4A671032.10304@mrabarnett.plus.com>

Ryniek90 wrote:
>>
>> ------------------------------------------------------------------------
>>
>> Temat:
>> Re: Changing the private variables content
>> Od:
>> Gary Herron <gherron at islandtraining.com>
>> Data:
>> Tue, 21 Jul 2009 14:14:44 -0700
>> Do:
>> Ryniek90 <ryniek90 at gmail.com>
>>
>> Do:
>> Ryniek90 <ryniek90 at gmail.com>
>> Kopia:
>> python-list at python.org
>>
>>
>> Ryniek90 wrote:
>>> Hi.
>>> I'm writing some class, and decided to use inside private method and 
>>> some private variables. While with method i haven't got any problem's 
>>> with variables i have.
>>> Maybe some example.
>>> A class with private method and private variable:
>>>
>>> "
>>> >>> class Secret(object):
>>>    #
>>>    def __init__(self):
>>>        self._number = 1
>>>    #
>>>    def _secret(self):
>>>        print self._number
>>>    def showit(self):
>>>        print "Secret number is:\n"
>>>        self._secret()
>>>
>>> >>> sec = Secret()
>>> >>> sec.showit()
>>> Secret number is:
>>>
>>> 1
>>> >>> sec._number
>>> 1
>>> >>> sec._number = 2
>>> >>> sec._number
>>> 2
>>> >>> sec._number += 3
>>> >>> sec._number
>>> 5
>>> >>>
>>> "
>>>
>>> As You can see, i made class with private method and private variable 
>>> inside __init__ constructor. I've changed also the variable value, 
>>> but outside class.
>>> I've got problem with changing some variable value _inside__my_ 
>>> class, which i'm writing.
>>
>> Not sure this is what you are asking, but a method (which is how I 
>> interpret "_inside__my_ class") changes the value by normal assignment 
>> like this:
>>
>> class Secret(object):
>>  ...
>>  def SetNumber(self,value):
>>    self._number = value
>>
>> Is that what you were asking?
>>
>>
>> Gary Herron
>>
>>
>>
>>> I've searched over google, some tuts with topics about operations on 
>>> private variables, but didn't found anything - only how to make them, 
>>> but no how to assign new objects/override them with new content (and 
>>> other advanced and helpful options).
>>>
>>> If someone could help me, it would be great.
>>>
>>> Thanks.
>>
>>
> 
> 
> Thanks for hint, but looks like i can't do what i want.
> 
> Maybe i show You my class:
> 
> "
> 
> class ModPrint(object):
>      u"""
>    This will be the doc.
>    """
>      def __init__(self):
>              #Assign the Python installation directory - sys.exec_prefix 
> - to variable
>        self._default_search_path=sys.exec_prefix
>        self._chosen_module = ''
>        self._user_search_path = ''
>        self._this_module = ''
>          def _SetVar(self, attr, val):
>        self.attr = val            def _search_for_module(self, *args):
>              """Private method which walks through default Python 
> installation directories, and search for prefered module."""
>              #walking thru all directories available in path 
> '_user_search_path'
>        for root, dirs, files in os.walk(self._user_search_path):
>            for f in files:
>                              #if found file 'f' is THAT module,
>                #full path to THAT file is assigned to variable
>                if f == ("%s.py" % self._chosen_module):
>                    self._SetVar(self._this_module, os.path.join(root, f))
>                                        def print_module(self, 
> _chosen_module='', _user_search_path='', 
> _default_search_path=sys.exec_prefix,):
>              """Reads module chosen by user, and returns full content of 
> this module, as it is."""
>                    #if custom search path hasn't been assigned,
>        #default path is being assigned as custom path
>        if self._user_search_path == '':
>            self._user_search_path = self._default_search_path
>                  #using private method '_search_for_module' with 'self.' 
> preffix
>        #to search for prefered module
>        self._search_for_module(_chosen_module, _user_search_path)
>              #opening prefered module with read-only binary mode
>        #and assigning it to 'module_open' variable
>        module_open = open(self._this_module, 'rb')
>              #reading this file and assigning it to variable
>        module_text = module_open.read()
>              #closing read file; the read content is still available
>        #it's stored in variable 'module_text'
>        module_open.close()
>              #returning the read content
>        return module_text
> 
> "
> 
> When i use this class in Python IDLE, i've got this error:
> "
>  >>> mod = ModPrint()
>  >>> import socket
>  >>> mod.print_module('socket')
> 
> Traceback (most recent call last):
>  File "<pyshell#60>", line 1, in <module>
>    mod.print_module('socket')
>  File "<pyshell#57>", line 48, in print_module
>    module_open = open(self._this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> As You can see, i can't assign the new value "os.path.join(root, f)" to 
> the 'self._this_module variable'.
> So for sure i've made some mistake in method:
> 
> "
> def _SetVar(self, attr, val):
>        self.attr = val   "
> When i've changed private variables to normal, stored in class (in 
> __init__ method), it was the same situation - i couldn't change this 
> variable value.
> 
> "
>  >>> mod = ModPrint()
>  >>> mod.print_module('os')
> 
> Traceback (most recent call last):
>  File "<pyshell#72>", line 1, in <module>
>    mod.print_module('os')
>  File "<pyshell#64>", line 48, in print_module
>    module_open = open(self.this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> Thanks i someone could help me, give some hint.

What is the point of the _SetVar method?

Instead of:

     self._SetVar(self._this_module, os.path.join(root, f))

just do:

     self._this_module = os.path.join(root, f)

(unless I'm misunderstanding what you're trying to do!)


From alan.isaac at gmail.com  Wed Jul 22 09:14:12 2009
From: alan.isaac at gmail.com (Alan G Isaac)
Date: Wed, 22 Jul 2009 13:14:12 GMT
Subject: invoke method on many instances
In-Reply-To: <mailman.3417.1248074972.8015.python-list@python.org>
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>	<02701d35$0$5185$c3e8da3@news.astraweb.com>	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
Message-ID: <EgE9m.507$646.499@nwrddc01.gnilink.net>

>>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>>> def apply2(itr, methodname, *args, **kwargs):
>>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>>     for item in itr:
>>>>         f(item)


>> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>>> for obj in objects:
>>>     getattr(obj, methodname)(*args, **kwargs)


> En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac:
>> Are there any obvious considerations in choosing 
>> between those two? 


On 7/20/2009 3:29 AM Gabriel Genellina apparently wrote:
> The operator.methodcaller version is faster in my tests for large 
> collections, but slightly slower when you have very few elements. 


So it seems.  Is this easily explained?

Thanks,
Alan Isaac


From breamoreboy at yahoo.co.uk  Wed Jul 22 09:18:55 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Wed, 22 Jul 2009 14:18:55 +0100
Subject: Python
In-Reply-To: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
References: <adf3e7ff0907211732t7f0a6c73qf072e05883a70be6@mail.gmail.com>
Message-ID: <h473jt$g3l$1@ger.gmane.org>

khanh le wrote:
> do you have any materials about Python?
> can you show me the link of Python or some books?
> thanks a lots!
> 
> -- 
> Regard!
> Khanh
> 
This comes highly recommeended http://diveintopython.org/

Regards.



From Caseyweb at gmail.com  Wed Jul 22 09:23:33 2009
From: Caseyweb at gmail.com (Casey Webster)
Date: Wed, 22 Jul 2009 06:23:33 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
Message-ID: <9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com>

On Jul 22, 5:27?am, Phillip B Oldham <phillip.old... at gmail.com> wrote:
> I understand that there are a number of MapReduce frameworks/tools
> that play nicely with Python (Disco, Dumbo/Hadoop), however these have
> "large" dependencies (Erlang/Java). Are there any MapReduce frameworks/
> tools which are either pure-Python, or play nicely with Python but
> don't require the Java/Erlang runtime environments?

I can't answer your question, but I would like to better understand
the
problem you are trying to solve.  The Apache Hadoop/MapReduce java
application isn't really that "large" by modern standards, although it
is generally run with large heap sizes for performance (-Xmx1024m or
larger for the mapred.child.java.opts parameter).

MapReduce is designed to do extremely fast parallel data set
processing
on terabytes of data over hundreds of physical nodes; what advantage
would a pure Python approach have here?


From contact at xavierho.com  Wed Jul 22 09:24:05 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 22 Jul 2009 23:24:05 +1000
Subject: Changing the private variables content
In-Reply-To: <4A671032.10304@mrabarnett.plus.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<4A670620.1090501@gmail.com> <4A671032.10304@mrabarnett.plus.com>
Message-ID: <2d56febf0907220624u7401550ei24461dd9ca7d6934@mail.gmail.com>

> What is the point of the _SetVar method?
>
>
So you can set any variable in that class, I guess?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/d1a3ee8c/attachment-0001.html>

From brendon.wickham at gmail.com  Wed Jul 22 09:28:16 2009
From: brendon.wickham at gmail.com (Brendon Wickham)
Date: Wed, 22 Jul 2009 23:28:16 +1000
Subject: Getting cookie "expires" value
Message-ID: <c07e3c70907220628t5b32e0f5s7ca3e422884e592b@mail.gmail.com>

Hi there,

My web application uses a cookie to set/get a session id. This is
working fine. However, I'm unable to work out how to get the cookie
"expires" value.

Below is test code that replicates the problem. It creates a simple
web page and shows a cookie value if it's found, or creates a new one
(correctly setting the "expires" value) and indicates that it was
created:

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
#!/usr/bin/env python
import Cookie,os

def printHeader():
??? print "Content-type: text/html\n"
??? print "<html><title>Cookie test</title>"
??? print "<body>"

cookies=Cookie.SimpleCookie(os.environ.get('HTTP_COOKIE'))

if cookies.has_key('test'):
??? #If cookie was found:
??? printHeader()
??? print "Found cookie:<br/><br/>"

??? #Get cookie:
??? c = cookies.get('test')

??? #Print its value:
??? print "<div>Value: %s</div>" % c.value

??? #Iterate through its items and print name/value:
??? for k,v in c.items():
??? ??? ?print "<div>%s=%s</div>" % (k,v)

else:
??? #Define cookie:
??? cookies['test'] = "1234"
??? cookies['test']['expires'] = 3600

??? #Save cookie:
??? print cookies['test']

??? #Now print HTML:
??? printHeader()

??? print "Cookie created."

print "</body></html>"
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<


This is what I get if the cookie exists:
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Found cookie:

Value: 1234
comment=
domain=
secure=
expires=
max-age=
version=
path=
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

As you can see, the cookie attributes are valueless. Can anyone help?
Am I missing something fundamental?

Cheers,

Brendon


From steve at REMOVE-THIS-cybersource.com.au  Wed Jul 22 09:28:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 22 Jul 2009 13:28:23 GMT
Subject: Changing the private variables content
References: <mailman.13231.1248210896.8014.python-list@python.org>
	<mailman.3521.1248265771.8015.python-list@python.org>
Message-ID: <02770500$0$5185$c3e8da3@news.astraweb.com>

On Wed, 22 Jul 2009 14:29:20 +0200, Ryniek90 wrote:

> When i use this class in Python IDLE, i've got this error: "
...
> Traceback (most recent call last):
>   File "<pyshell#60>", line 1, in <module>
>     mod.print_module('socket')
>   File "<pyshell#57>", line 48, in print_module
>     module_open = open(self._this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> As You can see, i can't assign the new value "os.path.join(root, f)" to
> the 'self._this_module variable'.

In the __init__ method, you successfully set the `_this_module` attribute:

        self._this_module = ''

That works, so it proves that you *can* set a private attribute.

Later on, you call the `_SetVar` method, which does this:

    def _SetVar(self, attr, val):
        self.attr = val   

In English, this method does this:

(1) Take two arguments, and store them in variables called "attr" and 
"val".

(2) Assign the value stored in "val" to an attribute named exactly "attr".

What you actually want is:

(1) Take two arguments, and store them in variables called "attr" and 
"val".

(2) Assign the value stored in "val" to an attribute with the name stored 
in the variable "attr".

Can you see the difference?

What you actually want is:

    def _SetVar(self, attr, val):
        setattr(self, attr, val)


Your code is terribly complicated. This will probably do what you want. 
(Warning -- I haven't tested it, so there may be a few errors.)


class ModPrint(object):
    u"""
    This will be the doc.
    """
    def __init__(self, default_search_path=''):
        self.default_search_path = ''

   def find_module(self, modulename, search_path=''):
       if search_path == '':
           # Try the default search path instead.
           search_path = self.default_search_path
        if search_path == '':  # still blank.
            # Try the Python search path instead.
           search_path = sys.exec_prefix
        for root, dirs, files in os.walk(search_path):
            for f in files:
                if f == "%s.py" % modulename:
                    return os.path.join(root, f)

    def get_module_text(self, modulename, search_path=''):
        filename = self.find_module(modulename, search_path)
        module_open = open(filename, 'rb')
        module_text = module_open.read()
        module_open.close()
        return module_text


I changed the name of print_module_text because it doesn't actually print 
anything.



-- 
Steven


From robin at reportlab.com  Wed Jul 22 09:37:35 2009
From: robin at reportlab.com (Robin Becker)
Date: Wed, 22 Jul 2009 14:37:35 +0100
Subject: Finding all cycles within an undirected graph
In-Reply-To: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
References: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
Message-ID: <4A67161F.8090908@chamonix.reportlab.co.uk>

disappearedng wrote:
> Hey everyone,
> I am interested to find out all the cycles within an undirected graph.
> I don't have a particular implementation of nodes and vertices yet, so
> would someone kindly point out a good graph library for this ( I
> looked at pygraph and python-graph, but not really satisfied ), in
> addition to good algorithm for solving this issue.

this one has been updated recently

http://code.google.com/p/python-graph/

also this page has many links http://wiki.python.org/moin/PythonGraphApi
-- 
Robin Becker



From jjkk73 at gmail.com  Wed Jul 22 09:39:09 2009
From: jjkk73 at gmail.com (jorma kala)
Date: Wed, 22 Jul 2009 15:39:09 +0200
Subject: How to document Python code properly for Pydoc
Message-ID: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>

Hi,
Do you know where I can find the rules for documenting Python code, so that
automatic document generation with Pydoc makes the most of the comments
inserted in the code?
I know about documenting class and method through triple quote just under
the class definition. But how do you comment a specific field or variable,
or how do you document function arguments so that they are extracted like in
javadoc?
Thanks very much
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/827104d7/attachment-0001.html>

From rhodri at wildebst.demon.co.uk  Wed Jul 22 10:01:09 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 22 Jul 2009 15:01:09 +0100
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <op.uxg2j7b5a8ncjz@gnudebst>

On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina  
<gagsl-py2 at yahoo.com.ar> wrote:


> class X(object):
>    foo = descriptor()
>
> x = X()
> x.foo = "value"

Isn't this going to create a brand new instance attribute x.foo that has  
nothing to do with the descriptor anyway?

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From ryniek90 at gmail.com  Wed Jul 22 10:01:19 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 22 Jul 2009 16:01:19 +0200
Subject: Changing the private variables content
In-Reply-To: <mailman.13388.1248268320.8014.python-list@python.org>
References: <mailman.13388.1248268320.8014.python-list@python.org>
Message-ID: <4A671BAF.1060204@gmail.com>

>
> Got it:
>
> exec('self.' + attr + '=\'' + val + '\'')
>
> That worked. I think it'll do what you want now ;)
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com <mailto:contact at xavierho.com>
> Website: http://xavierho.com/

To bad, that didn't worked in my class. Still the same error:
"
 >>> mod.print_module('socket')

Traceback (most recent call last):
  File "<pyshell#121>", line 1, in <module>
    mod.print_module('socket')
  File "<pyshell#118>", line 51, in print_module
    module_open = open(self._this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

:-/
> What is the point of the _SetVar method?
>
> Instead of:
>
>     self._SetVar(self._this_module, os.path.join(root, f))
>
> just do:
>
>     self._this_module = os.path.join(root, f)
>
> (unless I'm misunderstanding what you're trying to do!)
>

Of course i;ve tried, but still get the same error:

"
 >>> mod.print_module('socket')

Traceback (most recent call last):
  File "<pyshell#121>", line 1, in <module>
    mod.print_module('socket')
  File "<pyshell#118>", line 51, in print_module
    module_open = open(self.this_module, 'rb')
IOError: [Errno 2] No such file or directory: ''
 >>>
"

It looks like private variable have specific naure, that prevent from 
traditional editing them.
Still searching for some tuts about private methods and variables.


From Scott.Daniels at Acm.Org  Wed Jul 22 10:06:45 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 22 Jul 2009 07:06:45 -0700
Subject: Multiple versions of python
In-Reply-To: <98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
	<mailman.3465.1248186000.8015.python-list@python.org>
	<98c92c97-9e4c-4528-94e2-58ca6474e681@m11g2000yqh.googlegroups.com>
Message-ID: <PvqdnX-b4rW-hvrXnZ2dnUVZ_vydnZ2d@pdx.net>

CCW wrote:
> On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
>> The other thing you may want to do in a batch file is to change the file
>> associations so that you can run the .py file directly, without typing
>> "python" or "pythonw" in front of it.
>>
>> The relevant Windows commands are:     assoc and ftype      And on a
>> related note, you may want to edit the PATHEXT environment variable, to
>> add .PY and .PYW
> 
> Thanks for this - this way made a bit more sense to me.  I've now got
> C:\commands with the 4 .bat files in, and C:\commands in my path.  It
> all seems to work :) I think I've missed the point of the @ though -
> it doesn't seem to make any difference..
> 
> I'm also a bit confused with the associations - since I've got python
> 2.6 and 3.1, surely the command I type (python26 or python31) is the
> only way to force a script to be run using a specific interpreter at
> runtime without having to change the .bat file every time I want to
> run a script using 3.1 instead of 2.6?

OK, for me currently:

C:\> assoc .py
.py=Python.File

C:\> assoc .pyw
.pyw=Python.NoConFile

C:\> ftype Python.File
Python.File="C:\Python31\python.exe" "%1" %*

C:\> ftype Python.NoConFile
Python.NoConFile="C:\Python31\pythonw.exe" "%1" %*

C:\> ftype Python.File
Python.File="C:\Python31\python.exe" "%1" %*

Now imagine instead that you've added:

C:\> ftype Python31.File="C:\Python31\python.exe" "%1" %*
C:\> ftype Python31.NoConFile="C:\Python31\pythonw.exe" "%1" %*
C:\> ftype Python26.File="C:\Python26\python.exe" "%1" %*
C:\> ftype Python26.NoConFile="C:\Python26\pythonw.exe" "%1" %*

Then you can do the following:
C:\> assoc .py=Python26.File
C:\> fumble.py
C:\> assoc .py=Python31.File
C:\> fumble.py

That is the basic idea, but at the moment, I don't see a simple demo
working for me.  SO, if you want to pursue this, you can probably get it
to work.

--Scott David Daniels
Scott.Daniels at Acm.Org


From Scott.Daniels at Acm.Org  Wed Jul 22 10:12:18 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Wed, 22 Jul 2009 07:12:18 -0700
Subject: Issue combining gzip and subprocess
In-Reply-To: <m2eisam153.fsf@cs.uu.nl>
References: <mailman.3472.1248192725.8015.python-list@python.org>
	<m2eisam153.fsf@cs.uu.nl>
Message-ID: <2YednUGQxvntgfrXnZ2dnUVZ_hWdnZ2d@pdx.net>

Piet van Oostrum wrote:
> ...
> f = gzip.open(filename, 'w')
> proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
> while True:
>     line = proc.stdout.readline()
>     if not line: break
>     f.write(line)
> f.close()

Or even:
     proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
     with gzip.open(filename, 'w') as dest:
         for line in iter(proc.stdout, ''):
             f.write(line)

--Scott David Daniels
Scott.Daniels at Acm.Org


From invalid at invalid  Wed Jul 22 10:13:28 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 22 Jul 2009 09:13:28 -0500
Subject: plotting graph from another file
References: <mailman.3510.1248244109.8015.python-list@python.org>
Message-ID: <096dnaQneZwVg_rXnZ2dnUVZ_hZi4p2d@posted.visi>

On 2009-07-22, jhinak sen <jhinak.sen at gmail.com> wrote:

> i want to plot a distribution graph for following data:

[...]

> can it be done using matplotlib ?
>
> if yes , please give me the code for plotting the importing
> the text file and plotting the graph.

As soon as you're done cleaning my house, washing my car, and
running a few errands.

-- 
Grant Edwards                   grante             Yow! Of course, you
                                  at               UNDERSTAND about the PLAIDS
                               visi.com            in the SPIN CYCLE --


From disappearedng at gmail.com  Wed Jul 22 10:16:31 2009
From: disappearedng at gmail.com (disappearedng)
Date: Wed, 22 Jul 2009 22:16:31 +0800
Subject: Finding all cycles within an undirected graph (disappearedng)
Message-ID: <15dd54ec0907220716g34a806e1w5c2a93176172db20@mail.gmail.com>

Actually, I have realized that using the bit vector XOR method by
http://www.me.utexas.edu/~bard/IP/Handouts/cycles.pdf gives some
possibility of doing so. However this method is still experimental and
doesn't really have a definitive end to the algorithm (the base number
of vectors can change).

Any ideas anyone?

On Wed, Jul 22, 2009 at 9:12 PM, <python-list-request at python.org> wrote:
> Send Python-list mailing list submissions to
> ? ? ? ?python-list at python.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
> ? ? ? ?http://mail.python.org/mailman/listinfo/python-list
> or, via email, send a message with subject or body 'help' to
> ? ? ? ?python-list-request at python.org
>
> You can reach the person managing the list at
> ? ? ? ?python-list-owner at python.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Python-list digest..."
>
> Today's Topics:
>
> ? 1. Finding all cycles within an undirected graph (disappearedng)
> ? 2. Re: Re: Changing the private variables content (Xavier Ho)
> ? 3. Python-URL! - weekly Python news and links (Jul 22)
> ? ? ?(Gabriel Genellina)
> ? 4. Re: Multiple versions of python (Dave Angel)
> ? 5. Re: Changing the private variables content (MRAB)
>
>
> ---------- Forwarded message ----------
> From:?disappearedng <disappearedng at gmail.com>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 21:04:18 +0800
> Subject:?Finding all cycles within an undirected graph
> Hey everyone,
> I am interested to find out all the cycles within an undirected graph.
> I don't have a particular implementation of nodes and vertices yet, so
> would someone kindly point out a good graph library for this ( I
> looked at pygraph and python-graph, but not really satisfied ), in
> addition to good algorithm for solving this issue.
>
>
>
> ---------- Forwarded message ----------
> From:?Xavier Ho <contact at xavierho.com>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 23:06:22 +1000
> Subject:?Re: Re: Changing the private variables content
> Got it:
>
> exec('self.' + attr + '=\'' + val + '\'')
>
> That worked. I think it'll do what you want now ;)
>
> Ching-Yun "Xavier" Ho, Technical Artist
>
> Contact Information
> Mobile: (+61) 04 3335 4748
> Skype ID: SpaXe85
> Email: contact at xavierho.com
> Website: http://xavierho.com/
>
>
> ---------- Forwarded message ----------
> From:?"Gabriel Genellina" <python-url at phaseit.net>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 12:48:25 +0000 (UTC)
> Subject:?Python-URL! - weekly Python news and links (Jul 22)
> QOTW: ?"If programming is symbol manipulation, then you should remember that
> the user interface is also symbol manipulation, and it is a MUCH harder
> problem than databases, sorting, searching, and all the other problems you
> learn about in academia. The user interface has to communicate over a rich
> but noisy channel using multiple under-specified protocols to a couple of
> pounds of meat which processes information using buggy heuristics evolved
> over millions of years to find the ripe fruit, avoid being eaten, and have
> sex. If you think getting XML was hard, that's *nothing* compared to user
> interfaces.
>
> The fact that even bad UIs work at all is a credit to the heuristics, bugs
> and all, in the meat." - Steven D'Aprano
> ? ? http://groups.google.com/group/comp.lang.python/msg/8c65eacbd76e79cf
>
>
> ? ?Invoke the same method over every object in a collection:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/8fd293a9b39c8733/
>
> ? ?There is no 'xor' boolean operator, why? What should be its outcome?
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/16eec722310e75e8/
>
> ? ?A thread-safe method to create unique identifiers (not necesarily
> ? ?increasing integers):
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/dfe22a6446c057df/
>
> ? ?Tim Chase tells us three ways to turn standard output into unbuffered mode:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/a65f71444bd4bb53/
>
> ? ?How to receive data of unknown length using sockets:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/9e4a9f8b6e83320/
>
> ? ?Override a method, but keeping the inherited docstring:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/1e4075ba10dcbdd9/
>
> ? ?Limiting the execution time of a code fragment:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/734054de170e2904/
>
> ? ?Sharing a big object between processes using the multiprocessing module:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/833d4988b7af6353/
>
> ? ?Why aren't OrderedDicts [3.1] comparable using <, >, <=, >=?
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/c3c6f4fe7b6d487d/
>
> ? ?So many ways to call a function - why is that? Beginners get confused:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/3fd57f5ee4850530/
>
> ? ?The reasons to choose your favorite programming language (Python, I
> ? ?presume!):
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/5d87008e328efcf9/
>
> ? ?Tuples, lists, their differences and motivation:
> ? ? ? ?http://groups.google.com/group/comp.lang.python/browse_thread/thread/cb0cf56c52321ccc/
>
>
> ========================================================================
> Everything Python-related you want is probably one or two clicks away in
> these pages:
>
> ? ?Python.org's Python Language Website is the traditional
> ? ?center of Pythonia
> ? ? ? ?http://www.python.org
> ? ?Notice especially the master FAQ
> ? ? ? ?http://www.python.org/doc/FAQ.html
>
> ? ?PythonWare complements the digest you're reading with the
> ? ?marvelous daily python url
> ? ? ? ? http://www.pythonware.com/daily
>
> ? ?Just beginning with Python? ?This page is a great place to start:
> ? ? ? ?http://wiki.python.org/moin/BeginnersGuide/Programmers
>
> ? ?The Python Papers aims to publish "the efforts of Python enthusiasts":
> ? ? ? ?http://pythonpapers.org/
> ? ?The Python Magazine is a technical monthly devoted to Python:
> ? ? ? ?http://pythonmagazine.com
>
> ? ?Readers have recommended the "Planet" sites:
> ? ? ? ?http://planetpython.org
> ? ? ? ?http://planet.python.org
>
> ? ?comp.lang.python.announce announces new Python software. ?Be
> ? ?sure to scan this newsgroup weekly.
> ? ? ? ?http://groups.google.com/group/comp.lang.python.announce/topics
>
> ? ?Python411 indexes "podcasts ... to help people learn Python ..."
> ? ?Updates appear more-than-weekly:
> ? ? ? ?http://www.awaretek.com/python/index.html
>
> ? ?The Python Package Index catalogues packages.
> ? ? ? ?http://www.python.org/pypi/
>
> ? ?Much of Python's real work takes place on Special-Interest Group
> ? ?mailing lists
> ? ? ? ?http://www.python.org/sigs/
>
> ? ?Python Success Stories--from air-traffic control to on-line
> ? ?match-making--can inspire you or decision-makers to whom you're
> ? ?subject with a vision of what the language makes practical.
> ? ? ? ?http://www.pythonology.com/success
>
> ? ?The Python Software Foundation (PSF) has replaced the Python
> ? ?Consortium as an independent nexus of activity. ?It has official
> ? ?responsibility for Python's development and maintenance.
> ? ? ? ?http://www.python.org/psf/
> ? ?Among the ways you can support PSF is with a donation.
> ? ? ? ?http://www.python.org/psf/donations/
>
> ? ?The Summary of Python Tracker Issues is an automatically generated
> ? ?report summarizing new bugs, closed ones, and patch submissions.
> ? ? ? ?http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date
>
> ? ?Although unmaintained since 2002, the Cetus collection of Python
> ? ?hyperlinks retains a few gems.
> ? ? ? ?http://www.cetus-links.org/oo_python.html
>
> ? ?Python FAQTS
> ? ? ? ?http://python.faqts.com/
>
> ? ?The Cookbook is a collaborative effort to capture useful and
> ? ?interesting recipes.
> ? ? ? ?http://code.activestate.com/recipes/langs/python/
>
> ? ?Many Python conferences around the world are in preparation.
> ? ?Watch this space for links to them.
>
> ? ?Among several Python-oriented RSS/RDF feeds available, see:
> ? ? ? ?http://www.python.org/channews.rdf
> ? ?For more, see:
> ? ? ? ?http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
> ? ?The old Python "To-Do List" now lives principally in a
> ? ?SourceForge reincarnation.
> ? ? ? ?http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
> ? ? ? ?http://www.python.org/dev/peps/pep-0042/
>
> ? ?del.icio.us presents an intriguing approach to reference commentary.
> ? ?It already aggregates quite a bit of Python intelligence.
> ? ? ? ?http://del.icio.us/tag/python
>
> ? ?Enjoy the *Python Magazine*.
> ? ? ? ?http://pymag.phparch.com/
>
> ? ?*Py: the Journal of the Python Language*
> ? ? ? ?http://www.pyzine.com
>
> ? ?Dr.Dobb's Portal is another source of Python news and articles:
> ? ? ? ?http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
> ? ?and Python articles regularly appear at IBM DeveloperWorks:
> ? ? ? ?http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8
>
> Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
> ?http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
> ?http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
> ?http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes
>
> There is *not* an RSS for "Python-URL!"--at least not yet. ?Arguments
> for and against are occasionally entertained.
>
>
> Suggestions/corrections for next week's posting are always welcome.
> E-mail to <Python-URL at phaseit.net> should get through.
>
> To receive a new issue of this posting in e-mail each Monday morning
> (approximately), ask <claird at phaseit.net> to subscribe. ?Mention
> "Python-URL!". ?Write to the same address to unsubscribe.
>
>
> -- The Python-URL! Team--
>
> Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
> sponsor the "Python-URL!" project. ?Watch this space for upcoming
> news about posting archives.
>
>
>
> ---------- Forwarded message ----------
> From:?Dave Angel <davea at ieee.org>
> To:?CCW <c.c.wood at gmail.com>
> Date:?Wed, 22 Jul 2009 09:11:26 -0400
> Subject:?Re: Multiple versions of python
> CCW wrote:
>>
>> On 21 July, 15:19, Dave Angel <da... at dejaviewphoto.com> wrote:
>>
>>>
>>> ChrisW wrote:
>>>
>>>>
>>>> Hi,
>>>> ? ? ?I have installed 2 versions of python on my Windows XP computer - I
>>>> originally had 3.0.1, but then found that the MySQL module only
>>>> supported 2.*, so I've now installed that. ?I have found that if I
>>>> change the Windows Environment Variable path, then I can change the
>>>> version of python called when I type 'python' into a command line.
>>>> However, I'd like to be able to choose which version I use. ?I know
>>>> that if I change C:\Python26\python.exe to
>>>> C:\Python26\python2.exe and C:\Python30\python.exe to C:
>>>> \Python26\python3.exe, then typing 'python2' or 'python3' will invoke
>>>> the correct interpreter. ?However, is it safe just to rename the
>>>> executable files? Is there a more elegant way to achieve the same
>>>> task?
>>>> ? ? ?Thanks,
>>>> Chris
>>>>
>>>
>>> The elegant way is to have a batch directory on your PATH ( I use ?m:\t\bat ) ?and put your *.bat files there. ? I do NOT put any python
>>> installations on the PATH.
>>>
>>> For example, I have a batch file called: ? ? m:\t\bat\python26.bat
>>>
>>> c:\progfiles\python26\python.exe %*
>>>
>>> The %* syntax means pass all arguments through to the program.
>>>
>>> Once it all works, you can add an "@" in front of the c: ? in order to
>>> suppress echoing the command. ?At that point, it'll look and work the
>>> same way as what you did, but without modifying anything in the install
>>> directory. ? ?(You may want ?python26.bat, pythonw26.bat, python31.bat
>>> and pythonw31.bat)
>>>
>>> The other thing you may want to do in a batch file is to change the file
>>> associations so that you can run the .py file directly, without typing
>>> "python" or "pythonw" in front of it.
>>>
>>> The relevant Windows commands are: ? ? assoc and ftype ? ? ?And on a
>>> related note, you may want to edit the PATHEXT environment variable, to
>>> add .PY and .PYW
>>>
>>
>> Thanks for this - this way made a bit more sense to me. ?I've now got
>> C:\commands with the 4 .bat files in, and C:\commands in my path. ?It
>> all seems to work :) I think I've missed the point of the @ though -
>> it doesn't seem to make any difference..
>>
>> I'm also a bit confused with the associations - since I've got python
>> 2.6 and 3.1, surely the command I type (python26 or python31) is the
>> only way to force a script to be run using a specific interpreter at
>> runtime without having to change the .bat file every time I want to
>> run a script using 3.1 instead of 2.6?
>>
>>
>
> The @ symbol was used in older versions of CMD and COMMAND to suppress echoing of the command line. ?I think if you're using XP or later, it doesn't matter.
>
> As for file associations, I don't know just what you already know about. ?When you type ? ?data.doc ? ?at a command line, the system looks for the data file, then if it's found, it looks up the program associated with that extension. ?On my machine, that's a particular version of Word for Windows. ?Similarly, if I type ? ?digest.py ? and I'm in the directory containing that file, the system looks up my associations, and runs Python 2.6 on that file. ?If I wanted it to run Python 3.1 on that file, I'd have to change the associations, temporarily.
>
> So, first approximation, it's a way to avoid having to type PYTHON each time I want to run a script, as long as I don't need any other arguments on the (implied) command line. ?Further, the system will then look for digest.py everywhere on the PATH, so I don't even have to be in the same directory. ?And that means I can be in the data directory that digest.py is going to work on. ?Effectively, it raises digest.py to feeling like an executable, for most purposes. ?In fact, I put all my scripts in a directory, along with other simple executables. ? I use ?m:\t\bin ?for that purpose.
>
> These associations (to .py and .pyw) are established by the installer program for Python. ?But when you had multiple installs, you could choose whether the second one installed overrides the first. ?My point is that if you need to change them back and forth, you could use ?assoc and ftype to do it.
>
> On my system:
>
> M:\LabOrders>assoc .py
> .py=Python.File
>
> M:\LabOrders>ftype Python.File
> Python.File="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*
>
> M:\LabOrders>
>
>
> So my .py files are associated with the 2.6.2 version of ActivePython installation. ? Note the similarity of the ftype to your python26.bat file?
>
> One more little trick is that I could just type ? digest ? ?instead of ? ?digest.py, ? if I have added the .py and .pyw extensions to my ? PATHEXT environment variable. ? ?So my PATHEXT looks like:
> ?PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.PY;.PYW
>
>
>
> Note that the association changes made by ?assoc and ftype are global. ?They apply to all cmd.exe windows, even those already running, and they survive a reboot. ?But when you set environment variables like PATHEXT, ?you can choose to do it in a single window (with SET), or globally (using control-panel).
>
> If I found myself switching often, I'd make separate ftype entries for each interpreter, something like
> ?Python.File26="C:\PROGFI~1\ACTIVE~1\python.exe" "%1" %*
> ?Python.File31="C:\PROGFI~1\.....
> and just change assoc .py ?to point at the one I needed today.
>
> As it is, I'm content leaving the associations pointing at 2.6, and explicitly entering PYTHON31 in front of any script name I want to run on that interpreter.
>
> DaveA
>
>
>
>
> ---------- Forwarded message ----------
> From:?MRAB <python at mrabarnett.plus.com>
> To:?python-list at python.org
> Date:?Wed, 22 Jul 2009 14:12:18 +0100
> Subject:?Re: Changing the private variables content
> Ryniek90 wrote:
>>>
>>> ------------------------------------------------------------------------
>>>
>>> Temat:
>>> Re: Changing the private variables content
>>> Od:
>>> Gary Herron <gherron at islandtraining.com>
>>> Data:
>>> Tue, 21 Jul 2009 14:14:44 -0700
>>> Do:
>>> Ryniek90 <ryniek90 at gmail.com>
>>>
>>> Do:
>>> Ryniek90 <ryniek90 at gmail.com>
>>> Kopia:
>>> python-list at python.org
>>>
>>>
>>> Ryniek90 wrote:
>>>>
>>>> Hi.
>>>> I'm writing some class, and decided to use inside private method and some private variables. While with method i haven't got any problem's with variables i have.
>>>> Maybe some example.
>>>> A class with private method and private variable:
>>>>
>>>> "
>>>> >>> class Secret(object):
>>>> ? #
>>>> ? def __init__(self):
>>>> ? ? ? self._number = 1
>>>> ? #
>>>> ? def _secret(self):
>>>> ? ? ? print self._number
>>>> ? def showit(self):
>>>> ? ? ? print "Secret number is:\n"
>>>> ? ? ? self._secret()
>>>>
>>>> >>> sec = Secret()
>>>> >>> sec.showit()
>>>> Secret number is:
>>>>
>>>> 1
>>>> >>> sec._number
>>>> 1
>>>> >>> sec._number = 2
>>>> >>> sec._number
>>>> 2
>>>> >>> sec._number += 3
>>>> >>> sec._number
>>>> 5
>>>> >>>
>>>> "
>>>>
>>>> As You can see, i made class with private method and private variable inside __init__ constructor. I've changed also the variable value, but outside class.
>>>> I've got problem with changing some variable value _inside__my_ class, which i'm writing.
>>>
>>> Not sure this is what you are asking, but a method (which is how I interpret "_inside__my_ class") changes the value by normal assignment like this:
>>>
>>> class Secret(object):
>>> ?...
>>> ?def SetNumber(self,value):
>>> ? self._number = value
>>>
>>> Is that what you were asking?
>>>
>>>
>>> Gary Herron
>>>
>>>
>>>
>>>> I've searched over google, some tuts with topics about operations on private variables, but didn't found anything - only how to make them, but no how to assign new objects/override them with new content (and other advanced and helpful options).
>>>>
>>>> If someone could help me, it would be great.
>>>>
>>>> Thanks.
>>>
>>>
>>
>>
>> Thanks for hint, but looks like i can't do what i want.
>>
>> Maybe i show You my class:
>>
>> "
>>
>> class ModPrint(object):
>> ? ? u"""
>> ? This will be the doc.
>> ? """
>> ? ? def __init__(self):
>> ? ? ? ? ? ? #Assign the Python installation directory - sys.exec_prefix - to variable
>> ? ? ? self._default_search_path=sys.exec_prefix
>> ? ? ? self._chosen_module = ''
>> ? ? ? self._user_search_path = ''
>> ? ? ? self._this_module = ''
>> ? ? ? ? def _SetVar(self, attr, val):
>> ? ? ? self.attr = val ? ? ? ? ? ?def _search_for_module(self, *args):
>> ? ? ? ? ? ? """Private method which walks through default Python installation directories, and search for prefered module."""
>> ? ? ? ? ? ? #walking thru all directories available in path '_user_search_path'
>> ? ? ? for root, dirs, files in os.walk(self._user_search_path):
>> ? ? ? ? ? for f in files:
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? #if found file 'f' is THAT module,
>> ? ? ? ? ? ? ? #full path to THAT file is assigned to variable
>> ? ? ? ? ? ? ? if f == ("%s.py" % self._chosen_module):
>> ? ? ? ? ? ? ? ? ? self._SetVar(self._this_module, os.path.join(root, f))
>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? def print_module(self, _chosen_module='', _user_search_path='', _default_search_path=sys.exec_prefix,):
>> ? ? ? ? ? ? """Reads module chosen by user, and returns full content of this module, as it is."""
>> ? ? ? ? ? ? ? ? ? #if custom search path hasn't been assigned,
>> ? ? ? #default path is being assigned as custom path
>> ? ? ? if self._user_search_path == '':
>> ? ? ? ? ? self._user_search_path = self._default_search_path
>> ? ? ? ? ? ? ? ? #using private method '_search_for_module' with 'self.' preffix
>> ? ? ? #to search for prefered module
>> ? ? ? self._search_for_module(_chosen_module, _user_search_path)
>> ? ? ? ? ? ? #opening prefered module with read-only binary mode
>> ? ? ? #and assigning it to 'module_open' variable
>> ? ? ? module_open = open(self._this_module, 'rb')
>> ? ? ? ? ? ? #reading this file and assigning it to variable
>> ? ? ? module_text = module_open.read()
>> ? ? ? ? ? ? #closing read file; the read content is still available
>> ? ? ? #it's stored in variable 'module_text'
>> ? ? ? module_open.close()
>> ? ? ? ? ? ? #returning the read content
>> ? ? ? return module_text
>>
>> "
>>
>> When i use this class in Python IDLE, i've got this error:
>> "
>> ?>>> mod = ModPrint()
>> ?>>> import socket
>> ?>>> mod.print_module('socket')
>>
>> Traceback (most recent call last):
>> ?File "<pyshell#60>", line 1, in <module>
>> ? mod.print_module('socket')
>> ?File "<pyshell#57>", line 48, in print_module
>> ? module_open = open(self._this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>> ?>>>
>> "
>>
>> As You can see, i can't assign the new value "os.path.join(root, f)" to the 'self._this_module variable'.
>> So for sure i've made some mistake in method:
>>
>> "
>> def _SetVar(self, attr, val):
>> ? ? ? self.attr = val ? "
>> When i've changed private variables to normal, stored in class (in __init__ method), it was the same situation - i couldn't change this variable value.
>>
>> "
>> ?>>> mod = ModPrint()
>> ?>>> mod.print_module('os')
>>
>> Traceback (most recent call last):
>> ?File "<pyshell#72>", line 1, in <module>
>> ? mod.print_module('os')
>> ?File "<pyshell#64>", line 48, in print_module
>> ? module_open = open(self.this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>> ?>>>
>> "
>>
>> Thanks i someone could help me, give some hint.
>
> What is the point of the _SetVar method?
>
> Instead of:
>
> ? ?self._SetVar(self._this_module, os.path.join(root, f))
>
> just do:
>
> ? ?self._this_module = os.path.join(root, f)
>
> (unless I'm misunderstanding what you're trying to do!)
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From inky788 at gmail.com  Wed Jul 22 10:36:51 2009
From: inky788 at gmail.com (Inky 788)
Date: Wed, 22 Jul 2009 07:36:51 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com> 
	<mailman.3511.1248244497.8015.python-list@python.org>
Message-ID: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>

On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>
> > On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
>
> > wrote:
> > > [snip] We
> > > understand that lists are mutable and tuples are not, but we're a
> > > little lost as to why the two were kept separate from the start. They
> > > both perform a very similar job as far as we can tell.
>
> > My guess is that it was probably for optimization reasons long ago.
> > I've never heard a *good* reason why Python needs both.
>
> The good reason is the immutability, which lets you use
> a tuple as a dict key. ?

Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
just not sophisticated enough, but I've never wanted to use a list/
tuple as a dict key. This sounds like obscure usage, and a bit
contrived as a reason for having *both* lists and tuples.


From davea at ieee.org  Wed Jul 22 10:38:14 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 10:38:14 -0400
Subject: Ideas for problem with chat server application!
In-Reply-To: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
References: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
Message-ID: <4A672456.9010604@ieee.org>

David Adamo Jr. wrote:
> I developed a chat application with an attendant chat server.
> Everything is working fine. The issue now is the fact that whenever
> the chat server goes down (for instance, the server system shuts down
> as a result of power failure or some other problem), by the time the
> server system come back on, the chat server would have to be restarted
> manually.
>
> I believe (and I know) it is more appropriate for the chat server
> application to restart itself when the computer comes back on (and of
> course regardless of who is logged in and of course, even before
> anyone logs in). I have a batch file that executes the chat server. My
> attempt was to create a windows service that start automatically and
> runs this batch file using a Network Service account on the server
> system. Although, I'm having a hard time with this (temporarily), I
> would love to ask if there are any alternatives to using a windows
> service. Suggestions are highly appreciated.
>
>   
As a starting place, take a look at the Windows Scheduler.  One of the 
options is to schedule something at "boot."  That happens before anybody 
logs on to the system.  I don't know whether you can specify what user 
account will be used, but you can certainly launch a python program from 
there.

DaveA


From inky788 at gmail.com  Wed Jul 22 10:46:06 2009
From: inky788 at gmail.com (Inky 788)
Date: Wed, 22 Jul 2009 07:46:06 -0700 (PDT)
Subject: Documentation Problems
References: <h46rpv$lm5$1@adenine.netfront.net>
	<mailman.3518.1248261276.8015.python-list@python.org>
Message-ID: <b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>

On Jul 22, 7:15?am, Tim Golden <m... at timgolden.me.uk> wrote:
> Mark du Preez wrote:
> > Hi
>
> > Can anyone tell me where to go to suggest changes to the Python
> > documentation?
>
> Drop an entry in the tracker:
>
> ?http://bugs.python.org
>
> Patches are always welcome,

Could you please provide brief instructions on exactly how to go about
creating a suitable patch file? I mean, starting from the beginning
(as in, "check out code from {here} using {this command}", "cd to
{this} directory", "edit the file in place", "run {this} command to
create a patch file"). Or perhaps this procedure is already outlined
elsewhere?


From f.orndorffplunkett at gmail.com  Wed Jul 22 10:46:09 2009
From: f.orndorffplunkett at gmail.com (F.O.P.)
Date: Wed, 22 Jul 2009 07:46:09 -0700 (PDT)
Subject: Not understanding this documentation
Message-ID: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>

http://bugs.python.org/issue5358
I simply installed 3.0 on my ubuntubox brought my project from a
windows machine and made necessary changes to what I had used from os
and os.path.  I have an error at the end of this line:
for k in range(I):
and the error:
SyntaxError: invalid character in identifier

I've already declared I way above as the lenth of an array (I = len
(IA))
There shouldn't be a problem there aren't any issues with other
declarations identical to this.


From george.sakkis at gmail.com  Wed Jul 22 10:55:38 2009
From: george.sakkis at gmail.com (George Sakkis)
Date: Wed, 22 Jul 2009 07:55:38 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
Message-ID: <10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>

On Jul 22, 7:38?am, William Dode <w... at flibuste.net> wrote:

> I updated the script (python, c and java) with your unrolled version
> + somes litle thinks.
>
> I also tried with python3.1, unladen Q2, ironpython1.1.1
>
> Unfortunately it doesn't work more with shedskin, i'll see on the
> shedskin group...
>
> c 1.85s
> gcj 2.15s
> java 2.8s
> python2.5 + psyco 3.1s
> unladen-2009Q2 145s (2m45)
> python2.5 254s (4m14s)
> python3.1 300s (5m)
> ironpython1.1.1 680s (11m20)

Cool; it would be interesting to see the numbers for Jython and Boo as
well if it's not too much effort.

George


From kyrie at uh.cu  Wed Jul 22 11:01:20 2009
From: kyrie at uh.cu (Luis Alberto Zarrabeitia Gomez)
Date: Wed, 22 Jul 2009 11:01:20 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <1248274880.4a6729c036a68@comuh.uh.cu>


Quoting Inky 788 <inky788 at gmail.com>:

> > The good reason is the immutability, which lets you use
> > a tuple as a dict key. ?
> 
> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

I don't seem to understand your definition of obscure and contrived. It seems
that you got late to this thread, and you missed the examples. I'd suggest you
to go back on this thread and look at them. 


heights = {}
heights[1,2] = 5
heights[1,3] = 7
heights[3,5] = 1

addresses[lastname, firstname] = my_home_address

census[location, age] = census.get((location, age), 0) + 1

All those are using tuples as dict keys.

Regards,

-- 
Luis Zarrabeitia
Facultad de Matem?tica y Computaci?n, UH
http://profesores.matcom.uh.cu/~kyrie


-- 
Participe en Universidad 2010, del 8 al 12 de febrero de 2010
La Habana, Cuba 
http://www.universidad2010.cu



From rhodri at wildebst.demon.co.uk  Wed Jul 22 11:07:53 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 22 Jul 2009 16:07:53 +0100
Subject: Not understanding this documentation
In-Reply-To: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
Message-ID: <op.uxg5nfk3a8ncjz@gnudebst>

On Wed, 22 Jul 2009 15:46:09 +0100, F.O.P. <f.orndorffplunkett at gmail.com>  
wrote:

> http://bugs.python.org/issue5358
> I simply installed 3.0 on my ubuntubox brought my project from a
> windows machine and made necessary changes to what I had used from os
> and os.path.  I have an error at the end of this line:
> for k in range(I):
> and the error:
> SyntaxError: invalid character in identifier
>
> I've already declared I way above as the lenth of an array (I = len
> (IA))
> There shouldn't be a problem there aren't any issues with other
> declarations identical to this.

Could you show us slightly more of your code and the rest of the
error message, please?  I have a suspicion that the error actually
lies in the "necessary changes" you made.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From phillip.oldham at gmail.com  Wed Jul 22 11:09:31 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Wed, 22 Jul 2009 08:09:31 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com>
Message-ID: <123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com>

On Jul 22, 2:23?pm, Casey Webster <Casey... at gmail.com> wrote:
> I can't answer your question, but I would like to better understand
> the
> problem you are trying to solve. ?The Apache Hadoop/MapReduce java
> application isn't really that "large" by modern standards, although it
> is generally run with large heap sizes for performance (-Xmx1024m or
> larger for the mapred.child.java.opts parameter).
>
> MapReduce is designed to do extremely fast parallel data set
> processing
> on terabytes of data over hundreds of physical nodes; what advantage
> would a pure Python approach have here?

We're always taught that it is a good idea to reduce the number of
dependencies for a project. So you could use Disco, or Dumbo, or even
Skynet. But then you've introduced another system you have to manage.
Each new system will have a learning curve, which is lessened if the
system is written in an environment/language you already work with/
understand. And since a large cost with environments like erlang and
java is in understanding them any issues that are out of the ordinary
can be killer; changing the heap size as you mentioned above for Java
could be one of these issues that a non-java dev trying to use Hadoop
might come across.

With the advent of cloud computing and the new semi-structured/
document databases that are coming to the fore sometimes you need to
use MapReduce on smaller/fewer systems to the same effect. Also, you
may need only to ensure that a job is done in a timely fashion without
taking up too many resources, rather than lightening-fast. Dumbo/disco
in these situations may be considered overkill.

Implementations like BashReduce <http://blog.last.fm/2009/04/06/
mapreduce-bash-script> are perfect for such scenarios. I'm simply
wondering if there's another simpler/smaller implementation of
MapReduce that plays nicely with Python but doesn't require the setup/
knowledge overhead of more "robust" implementations such as hadoop and
disco... maybe similar to Ruby's Skynet.


From davea at ieee.org  Wed Jul 22 11:10:35 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 11:10:35 -0400
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <4A672BEB.6010008@ieee.org>

superpollo wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">hello clp.
>
> i can insert a hex value for a character literal in a string:
>
> >>> stuff = "\x45"
> >>> print stuff
> E
> >>>
>
> can i do something like the above, but using a *binary* number? (e.g. 
> 00101101 instead of 45) ?
>
> bye
>
> </div>
>
There's no way to get a binary value directly into a literal, but you 
can convert one into a string value, as follows:


x = 0b00101101
print x
print chr(x)

output is:
  45
  -

Note that this is decimal 45, which is different than the hex 45 you 
used in your first example.

For doing multiple characters, I can't see anything better than:

lis = [0b00101101, 0b01000101, 0b01100001]
print lis
s= "".join(chr(x) for x in lis)
print s

DaveA



From hackingkk at gmail.com  Wed Jul 22 11:35:19 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Wed, 22 Jul 2009 21:05:19 +0530
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
Message-ID: <1248276919.8402.6.camel@krishna-laptop>

hello all,
This is a real challenge and I don't know if a solution even exists for
this or not.

I am writing an application which I run as my usual user on ubuntu.
the usernake is let's say kk and it has sudo permission (meaning the
user is in the sudoers list ).


now when i do python myscript.py, the script has to change to another
non-privileged user for some tasks.
let's say for example switch to the postgres user which is dedicated for
postgres and has no other privileges.

I have tryed doing os.setuid(112) where 112 could be the uid of the user
I want the script to swith over.


but I got opperation not permitted.

I tryed using subprocess but that did not help me either.  I tryed sudo
su into the Popen command but it throws me into the terminal (shell)
with postgres as the user.

But that's now my desired result.
what I exactly want is that the script now continues to execute under
postgres user till the end.

I don't know how to achieve this iffect.

Infact I will need this during a serious deployment because i would have
my application run as a demon as a dedicated user.

I am finding some code for deamonising a python application but don't
know how to tell the script to change user.

happy hacking.
Krishnakant.




From davea at ieee.org  Wed Jul 22 11:39:51 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 22 Jul 2009 11:39:51 -0400
Subject: Changing the private variables content
In-Reply-To: <4A671BAF.1060204@gmail.com>
References: <mailman.13388.1248268320.8014.python-list@python.org>
	<4A671BAF.1060204@gmail.com>
Message-ID: <4A6732C7.7070909@ieee.org>

Ryniek90 wrote:
> <snip>
>
>
> It looks like private variable have specific naure, that prevent from 
> traditional editing them.
> Still searching for some tuts about private methods and variables.
>
>
There's no tutorial on private variables for good reason:

Private variables have no special characteristics.  The compiler and 
runtime library don't treat them specially (except for the highly 
controversial from xx import *).  It's strictly a programming 
convention.  You've got some other bugs in your code, which I can't help 
you with because your code comes across formatted so strangely that it 
cannot compile here.  Some things you might do to make it easier to get 
help:

1) make sure you're not mixing tabs and spaces in your source code
2) post using text messages, so they don't get reformatted.
3) copy/paste the code and error messages into your message, don't retype.
4) whenever you've made more than trivial changes to the code, repost it 
all, since it's very difficult to tell which suggestions you've 
followed, and which ones you haven't gotten yet, or maybe dismissed 
because they didn't work.

DaveA



From python at bdurham.com  Wed Jul 22 11:42:07 2009
From: python at bdurham.com (python at bdurham.com)
Date: Wed, 22 Jul 2009 11:42:07 -0400
Subject: Suggestions for Python MapReduce?
In-Reply-To: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
Message-ID: <1248277327.15700.1326268767@webmail.messagingengine.com>

Phillip,

We've had great success writing simple, project specific algorithms to
split content into chunks appropriate for ETL type, Python based
processing in a hosted cloud environment like Amazon EC2 or the recently
launched Rackspace Cloud Servers. Since we're purchasing our cloud
hosting time in 1 hour blocks, we divide our data into much larger
chunks than what a traditional map-reduce technique might use. For many
of our projects, the data transfer time to and from the cloud takes the
majority of clock time.

Malcolm


From jeanmichel at sequans.com  Wed Jul 22 12:07:07 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Wed, 22 Jul 2009 18:07:07 +0200
Subject: Changing the private variables content
In-Reply-To: <02770500$0$5185$c3e8da3@news.astraweb.com>
References: <mailman.13231.1248210896.8014.python-list@python.org>	<mailman.3521.1248265771.8015.python-list@python.org>
	<02770500$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A67392B.3090602@sequans.com>

Steven D'Aprano wrote:
> On Wed, 22 Jul 2009 14:29:20 +0200, Ryniek90 wrote:
>
>   
>> When i use this class in Python IDLE, i've got this error: "
>>     
> ...
>   
>> Traceback (most recent call last):
>>   File "<pyshell#60>", line 1, in <module>
>>     mod.print_module('socket')
>>   File "<pyshell#57>", line 48, in print_module
>>     module_open = open(self._this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>>  >>>
>> "
>>
>> As You can see, i can't assign the new value "os.path.join(root, f)" to
>> the 'self._this_module variable'.
>>     
>
> In the __init__ method, you successfully set the `_this_module` attribute:
>
>         self._this_module = ''
>
> That works, so it proves that you *can* set a private attribute.
>
> Later on, you call the `_SetVar` method, which does this:
>
>     def _SetVar(self, attr, val):
>         self.attr = val   
>
> In English, this method does this:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute named exactly "attr".
>
> What you actually want is:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute with the name stored 
> in the variable "attr".
>
> Can you see the difference?
>
> What you actually want is:
>
>     def _SetVar(self, attr, val):
>         setattr(self, attr, val)
>
>
> Your code is terribly complicated. This will probably do what you want. 
> (Warning -- I haven't tested it, so there may be a few errors.)
>
>
> class ModPrint(object):
>     u"""
>     This will be the doc.
>     """
>     def __init__(self, default_search_path=''):
>         self.default_search_path = ''
>
>    def find_module(self, modulename, search_path=''):
>        if search_path == '':
>            # Try the default search path instead.
>            search_path = self.default_search_path
>         if search_path == '':  # still blank.
>             # Try the Python search path instead.
>            search_path = sys.exec_prefix
>         for root, dirs, files in os.walk(search_path):
>             for f in files:
>                 if f == "%s.py" % modulename:
>                     return os.path.join(root, f)
>
>     def get_module_text(self, modulename, search_path=''):
>         filename = self.find_module(modulename, search_path)
>         module_open = open(filename, 'rb')
>         module_text = module_open.read()
>         module_open.close()
>         return module_text
>
>
> I changed the name of print_module_text because it doesn't actually print 
> anything.
>
>
>
>   
Moreover, if I'm not wrong there is absolutely no difference in the way 
python is handling private and public attributes, for python, both are 
the same kind of attributes. This is purely conventional (some doc 
processing tool will take into account the private prefix).

So there is absolutely no restriction in writing self._myVar = 0 in any 
of the instance methods.

JM



From ryniek90 at gmail.com  Wed Jul 22 12:10:52 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 22 Jul 2009 18:10:52 +0200
Subject: Python-list Digest, Vol 70, Issue 282
In-Reply-To: <mailman.13395.1248271304.8014.python-list@python.org>
References: <mailman.13395.1248271304.8014.python-list@python.org>
Message-ID: <4A673A0C.2000807@gmail.com>

>
>> When i use this class in Python IDLE, i've got this error: "
>>     
> ...
>   
>> Traceback (most recent call last):
>>   File "<pyshell#60>", line 1, in <module>
>>     mod.print_module('socket')
>>   File "<pyshell#57>", line 48, in print_module
>>     module_open = open(self._this_module, 'rb')
>> IOError: [Errno 2] No such file or directory: ''
>>  >>>
>> "
>>
>> As You can see, i can't assign the new value "os.path.join(root, f)" to
>> the 'self._this_module variable'.
>>     
>
> In the __init__ method, you successfully set the `_this_module` attribute:
>
>         self._this_module = ''
>
> That works, so it proves that you *can* set a private attribute.
>
> Later on, you call the `_SetVar` method, which does this:
>
>     def _SetVar(self, attr, val):
>         self.attr = val   
>
> In English, this method does this:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute named exactly "attr".
>
> What you actually want is:
>
> (1) Take two arguments, and store them in variables called "attr" and 
> "val".
>
> (2) Assign the value stored in "val" to an attribute with the name stored 
> in the variable "attr".
>
> Can you see the difference?
>
> What you actually want is:
>
>     def _SetVar(self, attr, val):
>         setattr(self, attr, val)
>
>
> Your code is terribly complicated. This will probably do what you want. 
> (Warning -- I haven't tested it, so there may be a few errors.)
>
>
> class ModPrint(object):
>     u"""
>     This will be the doc.
>     """
>     def __init__(self, default_search_path=''):
>         self.default_search_path = ''
>
>    def find_module(self, modulename, search_path=''):
>        if search_path == '':
>            # Try the default search path instead.
>            search_path = self.default_search_path
>         if search_path == '':  # still blank.
>             # Try the Python search path instead.
>            search_path = sys.exec_prefix
>         for root, dirs, files in os.walk(search_path):
>             for f in files:
>                 if f == "%s.py" % modulename:
>                     return os.path.join(root, f)
>
>     def get_module_text(self, modulename, search_path=''):
>         filename = self.find_module(modulename, search_path)
>         module_open = open(filename, 'rb')
>         module_text = module_open.read()
>         module_open.close()
>         return module_text
>
>
> I changed the name of print_module_text because it doesn't actually print 
> anything.
>   

Thanks for ready class - it works great, but that code:
"

What you actually want is:

    def _SetVar(self, attr, val):
        setattr(self, attr, val)


"
Didn't worked, so i wil reuse your class, and modify it later. Now i see 
that working on private objects complex.



From junhufr at gmail.com  Wed Jul 22 12:13:37 2009
From: junhufr at gmail.com (Jun)
Date: Wed, 22 Jul 2009 09:13:37 -0700 (PDT)
Subject: Copy/paste through LAN
Message-ID: <c1e24f0f-b34f-45e8-81bd-118baa1e8632@c29g2000yqd.googlegroups.com>

Hello,

I've a client/server application which uses Pyro to communicate each
other.
Now i try to implement copy/paste through LAN between server
controlled
filesystem to my local windows machine (I could list files in client's
window).
How can i pass the url information through Pyro ?

Thank you in advance.

Jun


From tjreedy at udel.edu  Wed Jul 22 12:28:04 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:28:04 -0400
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <h47emj$ogf$1@ger.gmane.org>

superpollo wrote:
> hello clp.
> 
> i can insert a hex value for a character literal in a string:
> 
>  >>> stuff = "\x45"
>  >>> print stuff
> E
>  >>>
> 
> can i do something like the above, but using a *binary* number? (e.g. 
> 00101101 instead of 45) ?

Language Ref 2.4. Literals



From rNOSPAMon at flownet.com  Wed Jul 22 12:36:28 2009
From: rNOSPAMon at flownet.com (Ron Garret)
Date: Wed, 22 Jul 2009 09:36:28 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
Message-ID: <rNOSPAMon-7C2B71.09362722072009@news.albasani.net>

In article <uRr9m.6558$ze1.5162 at news-server.bigpond.net.au>,
 Neil Hodgson <nyamatongwe+thunder at gmail.com> wrote:

> milanj:
> 
> > and all of them use native threads (python still use green threads ?)
> 
>    Python uses native threads.

But then it adds the global interpreter lock, which completely 
undermines the utility of native threads.  So yes, it uses native 
threads, but it does not actually realize the benefits of that use.

rg


From sjmachin at lexicon.net  Wed Jul 22 12:37:16 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 22 Jul 2009 09:37:16 -0700 (PDT)
Subject: Not understanding this documentation
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
Message-ID: <dd96ba46-a411-4b51-9c73-a0dea2da680d@g1g2000pra.googlegroups.com>

On Jul 23, 12:46?am, "F.O.P." <f.orndorffplunk... at gmail.com> wrote:
> http://bugs.python.org/issue5358
> I simply installed 3.0 on my ubuntubox brought my project from a
> windows machine and made necessary changes to what I had used from os
> and os.path. ?I have an error at the end of this line:
> for k in range(I):
> and the error:
> SyntaxError: invalid character in identifier
>
> I've already declared I way above as the lenth of an array (I = len
> (IA))
> There shouldn't be a problem there aren't any issues with other
> declarations identical to this.

You are have used the --ftniv and --strict  options and hence it's
objecting to the lower-case "k".



From tjreedy at udel.edu  Wed Jul 22 12:38:22 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:38:22 -0400
Subject: Documentation Problems
In-Reply-To: <7coan1F28i1q2U1@mid.uni-berlin.de>
References: <h46rpv$lm5$1@adenine.netfront.net>
	<7coan1F28i1q2U1@mid.uni-berlin.de>
Message-ID: <h47f9u$sko$1@ger.gmane.org>

Diez B. Roggisch wrote:
> Mark du Preez wrote:
> 
>> Hi
>>
>> Can anyone tell me where to go to suggest changes to the Python
>> documentation?
>>
>> Thanks.
> 
> http://docs.python.org/ has a "bugs"-section that leads to
> 
> http://docs.python.org/bugs.html
> 
> You can file doc-bugs in the tracker, and check if they are already fixed in
> the dev-docs.

Actually, check first at

http://docs.python.org/dev/py3k/     for 3.2a
http://docs.python.org/dev/          for 2.7a

These are updated often, perhaps nightly.
Then file if you still think a change is needed.

For small changes, a specific suggested rewording is sufficient.

"Change 'tihs' to 'this'."

"Between 'Sentence 1' and 'sentence 2', I suggest adding 'sentence 3'."

The doc maintainers are happy to do the rst formatting themselves.



From tjreedy at udel.edu  Wed Jul 22 12:44:08 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:44:08 -0400
Subject: doted filenames in import statements
In-Reply-To: <4A670313.8040204@sequans.com>
References: <mailman.3488.1248212574.8015.python-list@python.org>	<m2prbtllen.fsf@cs.uu.nl>
	<4A670313.8040204@sequans.com>
Message-ID: <h47fko$tqp$1@ger.gmane.org>

Jean-Michel Pichavant wrote:
> Piet van Oostrum wrote:
>>
>> [snip]
>>
>>> JP> file = "/home/dsp/4.6.0.0/test.py"
>>> JP> test = __import__(file)
>>> JP> => no module name blalalal found.
>>>     
>>
>>  
>>> JP> Any suggestion ? I tried multiple escape technics without any 
>>> success.
>>>     
>>
>> Rightly so.
>>
>> I think the best would be to add the directory to sys.path 
>> sys.path.add('/home/dsp/4.6.0.0')
>> and then
>> __import__('test', ... )   
> 
> I see. My problem is that a have to import 2 different files having de 
> same name. In the same name space I have 2 objects from 2 different 
> software branches, let's say 4.6.0 and 4.6.1.
> The first object shall import 4.6.0/orb.py and the second one 4.6.1/orb.py.
> 
> If I add 4.6.1 to sys.path, the import statement will look like:
> self._orb = __import__('orb')
> The problem is, python wil assume orb is already imported and will 
> assign the module from the 4.6.0 branch to my 4.6.1 object.
> 
> Do I have to mess up with sys.modules keys to make python import the 
> correct file ? Is there a standard/proper way to do that ?

If you make the directory names into proper identifiers like v460 and 
v461 and add __init__.py to each to make them packages and have both on 
search path, then

import v460.orb #or import v460.orb as orb460
import v461.orb #or import v460.orb as orb461

will get you both. One way or another, they have to get different names 
within Python.

Terry Jan Reedy



From wilk at flibuste.net  Wed Jul 22 12:45:19 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 16:45:19 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
Message-ID: <4a67421e$0$31038$426a74cc@news.free.fr>

On 22-07-2009, George Sakkis wrote:
> On Jul 22, 7:38?am, William Dode <w... at flibuste.net> wrote:
>
>> I updated the script (python, c and java) with your unrolled version
>> + somes litle thinks.
>>
>> I also tried with python3.1, unladen Q2, ironpython1.1.1
>>
>> Unfortunately it doesn't work more with shedskin, i'll see on the
>> shedskin group...
>>
>> c 1.85s
>> gcj 2.15s
>> java 2.8s
>> python2.5 + psyco 3.1s
>> unladen-2009Q2 145s (2m45)
>> python2.5 254s (4m14s)
>> python3.1 300s (5m)
>> ironpython1.1.1 680s (11m20)
>
> Cool; it would be interesting to see the numbers for Jython and Boo as
> well if it's not too much effort.

I just tried with jython, but oddly it's faster without array.
Thanks to Mark, i could compile to shedskin again.
And add somes little improvements...

c 1.65s
gcj 1.9s
java 2.4s
python2.5 + psyco 2.9s
shedskin 3.4s
unladen-2009Q2 125s (2m05)
Jython 2.2.1 on java1.6.0_12 176s (without array, like shedskin)
Jython 2.2.1 on java1.6.0_12 334s (with array)
python2.5 215s (3m35s)
python3.1 246s (4m06s)
ironpython1.1.1 512 (8m32s)


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From f.orndorffplunkett at gmail.com  Wed Jul 22 12:45:58 2009
From: f.orndorffplunkett at gmail.com (F.O.P.)
Date: Wed, 22 Jul 2009 09:45:58 -0700 (PDT)
Subject: Not understanding this documentation
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
	<mailman.3538.1248275284.8015.python-list@python.org>
Message-ID: <081d1a50-fd7f-4f87-889e-262bc7e2debd@x5g2000prf.googlegroups.com>

On Jul 22, 9:07?am, "Rhodri James" <rho... at wildebst.demon.co.uk>
wrote:
> On Wed, 22 Jul 2009 15:46:09 +0100, F.O.P. <f.orndorffplunk... at gmail.com> ?
> wrote:
>
> >http://bugs.python.org/issue5358
> > I simply installed 3.0 on my ubuntubox brought my project from a
> > windows machine and made necessary changes to what I had used from os
> > and os.path. ?I have an error at the end of this line:
> > for k in range(I):
> > and the error:
> > SyntaxError: invalid character in identifier
>
> > I've already declared I way above as the lenth of an array (I = len
> > (IA))
> > There shouldn't be a problem there aren't any issues with other
> > declarations identical to this.
>
> Could you show us slightly more of your code and the rest of the
> error message, please? ?I have a suspicion that the error actually
> lies in the "necessary changes" you made.
>
> --
> Rhodri James *-* Wildebeest Herder to the Masses

I spoke to a friend about it and he found that I had put in a unicode
"semicolon" rather than ASCII.
I feel silly for asking a question like this but there's really no
harm done in asking.  Thank you for the quick response Rhodri!  Much
appreciated!
Cheers


From tjreedy at udel.edu  Wed Jul 22 12:47:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:47:15 -0400
Subject: Finding all cycles within an undirected graph
In-Reply-To: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
References: <15dd54ec0907220604gf7f760w98cad7d6f042ebac@mail.gmail.com>
Message-ID: <h47fqi$tqp$2@ger.gmane.org>

disappearedng wrote:
> Hey everyone,
> I am interested to find out all the cycles within an undirected graph.

I think you have to qualify that as 'minimal cycles' to have a 
well-defined problem.



From http  Wed Jul 22 12:55:51 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 09:55:51 -0700
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com>
	<123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com>
Message-ID: <7xws60u06g.fsf@ruckus.brouhaha.com>

Phillip B Oldham <phillip.oldham at gmail.com> writes:
> Implementations like BashReduce <http://blog.last.fm/2009/04/06/
> mapreduce-bash-script> are perfect for such scenarios. I'm simply
> wondering if there's another simpler/smaller implementation of
> MapReduce that plays nicely with Python but doesn't require the setup/
> knowledge overhead of more "robust" implementations such as hadoop and
> disco... maybe similar to Ruby's Skynet.

I usually just spew ssh tasks across whatever computing nodes I can
get my hands on.  It's less organized than something like mapreduce,
but I tend to run one-off tasks that I have to keep an eye on anyway.
I've done stuff like that across up to 100 or so machines and I think
it wouldn't be really worse if the number were a few times higher.  I
don't think it would scale to really large (10,000's of nodes) clusters.


From tjreedy at udel.edu  Wed Jul 22 12:59:01 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 12:59:01 -0400
Subject: Not understanding this documentation
In-Reply-To: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
Message-ID: <h47ggl$tn$1@ger.gmane.org>

F.O.P. wrote:

Your subject line should have been  about "SyntaxError message"

> http://bugs.python.org/issue5358

Why reference this? Unless you added zero-width joiners in the move, 
this is irrelevant noise.

> I simply installed 3.0 on my ubuntubox

Upgrade to 3.1 as soon as you can. Works better.

> brought my project from a
> windows machine and made necessary changes to what I had used from os
> and os.path.  I have an error at the end of this line:
> for k in range(I):
> and the error:
> SyntaxError: invalid character in identifier
> 
> I've already declared I way above as the lenth of an array (I = len
> (IA))
> There shouldn't be a problem there aren't any issues with other
> declarations identical to this.

I otherwise concur with R. James as there is no syntax error posted.
To make sure there is nothing invisible in that line, do
print(repr("for k in range(I):")) # should be no escaped chars and
print(len("for k in range(I):")) # should be 18, I believe

tjr



From pavlovevidence at gmail.com  Wed Jul 22 13:01:31 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 10:01:31 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
Message-ID: <4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>

On Jul 22, 9:36?am, Ron Garret <rNOSPA... at flownet.com> wrote:
> In article <uRr9m.6558$ze1.5... at news-server.bigpond.net.au>,
> ?Neil Hodgson <nyamatongwe+thun... at gmail.com> wrote:
>
> > milanj:
>
> > > and all of them use native threads (python still use green threads ?)
>
> > ? ?Python uses native threads.
>
> But then it adds the global interpreter lock, which completely
> undermines the utility of native threads. ?So yes, it uses native
> threads, but it does not actually realize the benefits of that use.

Wrong.  It only partially undermines the utility of native threads,
not completely.  Native threading allows some threads to run while
others are blocked in a system call (as well as in a few other minor
cases), which can't be done with green threads.


Carl Banks


From lie.1296 at gmail.com  Wed Jul 22 13:19:02 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 23 Jul 2009 03:19:02 +1000
Subject: Documentation Problems
In-Reply-To: <b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>
References: <h46rpv$lm5$1@adenine.netfront.net>	<mailman.3518.1248261276.8015.python-list@python.org>
	<b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>
Message-ID: <h47hm9$577$1@ger.gmane.org>

Inky 788 wrote:
> On Jul 22, 7:15 am, Tim Golden <m... at timgolden.me.uk> wrote:
>> Mark du Preez wrote:
>>> Hi
>>> Can anyone tell me where to go to suggest changes to the Python
>>> documentation?
>> Drop an entry in the tracker:
>>
>>  http://bugs.python.org
>>
>> Patches are always welcome,
> 
> Could you please provide brief instructions on exactly how to go about
> creating a suitable patch file? I mean, starting from the beginning
> (as in, "check out code from {here} using {this command}", "cd to
> {this} directory", "edit the file in place", "run {this} command to
> create a patch file"). Or perhaps this procedure is already outlined
> elsewhere?

It's the typical svn-based development, "svn checkout" from the
repository (see list of svn urls here:
http://www.python.org/dev/faq/#how-do-i-get-a-checkout-of-the-repository-read-only-and-read-write),
modify the files, then "svn diff" (or "diff -u")

And last but not least, check out the dev-faq:
http://www.python.org/dev/faq/



From http  Wed Jul 22 13:20:20 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 10:20:20 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
Message-ID: <7xskgobpnv.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> Wrong.  It only partially undermines the utility of native threads,
> not completely.  Native threading allows some threads to run while
> others are blocked in a system call (as well as in a few other minor
> cases), which can't be done with green threads.

Why is that such an advantage?  Green threads work fine if you just
organize the i/o system to never block.  


From king.seth at gmail.com  Wed Jul 22 13:32:51 2009
From: king.seth at gmail.com (Seth)
Date: Wed, 22 Jul 2009 10:32:51 -0700 (PDT)
Subject: Pyserial and pyQt
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
	<h45inh$ofk$1@get-news01.get.basefarm.net>
Message-ID: <70e4ebae-908f-4f3a-a96a-6fa0a7a7887a@y19g2000yqy.googlegroups.com>

On Jul 21, 7:24?pm, David Boddie <da... at boddie.org.uk> wrote:
> On Tuesday 21 July 2009 21:37, Seth wrote:
>
> > I have used pyserial in the past but this is my first experience with
> > pyQt. ?I am using the Python xy package for windows current but might
> > move to linux. ?I have a small device that is outputting a basic text
> > string. ?I want to be able to read this string(from the comm port) and
> > update a text box and eventually a graph in pyQt. ?I can't find any
> > documentation or tutorials on how to do this. ?If anyone can point me
> > in the right direction or give me some tips I would be grateful.
>
> It seems that someone has already asked a similar question on Stack
> Overflow, though perhaps you should start with a simpler solution
> and look at more advanced ones later:
>
> ?http://stackoverflow.com/questions/771988/pyqt4-and-pyserial
>
> One starting point is this list of tutorials on the PyQt and PyKDE Wiki:
>
> ?http://www.diotavelli.net/PyQtWiki/Tutorials
>
> Later, when you want to draw graphs, you might find PyQwt useful:
>
> ?http://pyqwt.sourceforge.net/
>
> You may already be aware that there's also a mailing list for PyQt and
> PyKDE:
>
> ?http://www.riverbankcomputing.com/pipermail/pyqt/
>
> Another way to get answers to questions is to join the #pyqt IRC channel
> at freenode.net:
>
> ? irc://irc.freenode.net/
>
> David


Thanks for the response.  I have gone through a lot of the tutorials.
All of them(that I saw) seem to just deal will event-based
applications ie calculator, image viewer, etc.  How do I run pyserial
in the background and pass the information to PyQT and refresh the
screen?  Is there a way to have pyserial run in another thread and
pass the information to the UI?

Thanks,
Seth


From lie.1296 at gmail.com  Wed Jul 22 13:43:14 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Thu, 23 Jul 2009 03:43:14 +1000
Subject: How to document Python code properly for Pydoc
In-Reply-To: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>
References: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>
Message-ID: <h47j3k$9gj$1@ger.gmane.org>

jorma kala wrote:
> Hi,
> Do you know where I can find the rules for documenting Python code, so
> that automatic document generation with Pydoc makes the most of the
> comments inserted in the code?
> I know about documenting class and method through triple quote just
> under the class definition. But how do you comment a specific field or
> variable, or how do you document function arguments so that they are
> extracted like in javadoc?
> Thanks very much

pydoc is a simple tool, and doesn't do much. You write in freeform,
although generally you'll do something like this:

def myfunc(a, b):
    '''
    short description of myfunc

    longer description of myfunc, if necessary, and typically includes
    description of the arguments and the behaviors. Also includes the
    description of the return value.
    '''

    pass

pydoc doesn't recognize any special markups. If you want to get more
from the docstring, you need other documentation generator such as
epydoc, Doxygen, or Sphinx.



From phillip.oldham at gmail.com  Wed Jul 22 13:51:17 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Wed, 22 Jul 2009 10:51:17 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com> 
	<123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com> 
	<7xws60u06g.fsf@ruckus.brouhaha.com>
Message-ID: <83889f6f-1e40-435e-b947-af17964e90af@d32g2000yqh.googlegroups.com>

On Jul 22, 5:55?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Phillip B Oldham <phillip.old... at gmail.com> writes:
> I usually just spew ssh tasks across whatever computing nodes I can
> get my hands on. ?It's less organized than something like mapreduce,
> but I tend to run one-off tasks that I have to keep an eye on anyway.

I'm thinking of repeated tasks; things you run regularly, but don't
need to be blisteringly fast. I'll more than likely use Disco, but if
I were to find something more light-weight I'd take a serious look.



From wilk at flibuste.net  Wed Jul 22 13:55:34 2009
From: wilk at flibuste.net (William Dode)
Date: 22 Jul 2009 17:55:34 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
	<4a67421e$0$31038$426a74cc@news.free.fr>
Message-ID: <4a675296$0$1549$426a74cc@news.free.fr>

On 22-07-2009, William Dode wrote:

> c 1.65s
> gcj 1.9s
> java 2.4s
> python2.5 + psyco 2.9s
> shedskin 3.4s

with -bw i have 2.6s

> unladen-2009Q2 125s (2m05)
> Jython 2.2.1 on java1.6.0_12 176s (without array, like shedskin)
> Jython 2.2.1 on java1.6.0_12 334s (with array)
> python2.5 215s (3m35s)
> python3.1 246s (4m06s)
> ironpython1.1.1 512 (8m32s)

somebody can test with ironpython on windows ?

Anyway, it's very impressive. I wonder if unladen will be so close in 
the futur.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From pavlovevidence at gmail.com  Wed Jul 22 13:59:50 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 10:59:50 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
Message-ID: <5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>

On Jul 22, 10:20?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > Wrong. ?It only partially undermines the utility of native threads,
> > not completely. ?Native threading allows some threads to run while
> > others are blocked in a system call (as well as in a few other minor
> > cases), which can't be done with green threads.
>
> Why is that such an advantage? ?Green threads work fine if you just
> organize the i/o system to never block. ?

Because then I don't have to organize the I/O system never to block.


Carl Banks


From davidj411 at gmail.com  Wed Jul 22 14:04:36 2009
From: davidj411 at gmail.com (davidj411)
Date: Wed, 22 Jul 2009 11:04:36 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com> 
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com> 
	<16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com>
Message-ID: <524a57a9-ba45-459b-b62d-81f527888a4e@j19g2000vbp.googlegroups.com>

i never heard of the logging module, but this function seemed simple
enough.

i assume this link is what you refering to:
http://docs.python.org/library/logging.html

thanks for the helpful info. i think "Piet van Oostrum" has resolved
my issue. good eyes!


From dangets at gmail.com  Wed Jul 22 14:15:55 2009
From: dangets at gmail.com (DG)
Date: Wed, 22 Jul 2009 11:15:55 -0700 (PDT)
Subject: list of 'magic methods' or builtin class methods... want to exclude 
	those from dir output
Message-ID: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>

There is probably a better way to do this (please enlighten me, if you
know), but what I want to do is get a list of a class' attributes
minus whatever the 'builtin' methods are.  I would also like to do
this for instances of classes as well.  I don't want to use __dict__
because I want to get all of the attributes that have been added
throughout the inheritance tree, just not the builtin ones.

I was wondering if there is a function to return a list of these, so I
could perform a 'dir' on the object (class or instance) and filter out
the builtin attributes.  I know I could create my own list something
like
['__class__', '__delattr__', ..., '__weakref__'] and use that.  I
would see this being fragile to Python version differences as new ones
are added or taken away.

A more flexible way is to have the list be filled out dynamically by
creating a 'junk' class that inherits only from object and storing
it's dir() output into the filter list.  This is probably what I'll do
unless someone knows of a builtin function that will give me a
(version-safe) list.

Thanks!


From dangets at gmail.com  Wed Jul 22 14:24:21 2009
From: dangets at gmail.com (DG)
Date: Wed, 22 Jul 2009 11:24:21 -0700 (PDT)
Subject: list of 'magic methods' or builtin class methods... want to 
	exclude those from dir output
References: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
Message-ID: <d0773262-53e8-4b48-a931-0c16ad64a034@a39g2000pre.googlegroups.com>

On Jul 22, 12:15?pm, DG <dang... at gmail.com> wrote:
> There is probably a better way to do this (please enlighten me, if you
> know), but what I want to do is get a list of a class' attributes
> minus whatever the 'builtin' methods are. ?I would also like to do
> this for instances of classes as well. ?I don't want to use __dict__
> because I want to get all of the attributes that have been added
> throughout the inheritance tree, just not the builtin ones.
>
> I was wondering if there is a function to return a list of these, so I
> could perform a 'dir' on the object (class or instance) and filter out
> the builtin attributes. ?I know I could create my own list something
> like
> ['__class__', '__delattr__', ..., '__weakref__'] and use that. ?I
> would see this being fragile to Python version differences as new ones
> are added or taken away.
>
> A more flexible way is to have the list be filled out dynamically by
> creating a 'junk' class that inherits only from object and storing
> it's dir() output into the filter list. ?This is probably what I'll do
> unless someone knows of a builtin function that will give me a
> (version-safe) list.
>
> Thanks!

Haha, replying to my own post.  Here is the implementation of my idea
of dynamically creating the filter lists from a 'junk' object.  As of
now it appears that the dir output of a class is the same as the dir
output of an instance, but if that ever changes, this should future
proof it.  This is only a 4-liner, so it is probably good enough for
what I want to do, but I would rather use a builtin/standard way if
there is one.

class A(object):
    pass
class_filter_methods = dir(A)
instance_filter_methods = dir(A())



From dangets at gmail.com  Wed Jul 22 14:28:58 2009
From: dangets at gmail.com (DG)
Date: Wed, 22 Jul 2009 11:28:58 -0700 (PDT)
Subject: list of 'magic methods' or builtin class methods... want to 
	exclude those from dir output
References: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
	<d0773262-53e8-4b48-a931-0c16ad64a034@a39g2000pre.googlegroups.com>
Message-ID: <48e4e3e1-7356-451e-845b-46516ead98b7@v37g2000prg.googlegroups.com>

On Jul 22, 12:24?pm, DG <dang... at gmail.com> wrote:
> On Jul 22, 12:15?pm, DG <dang... at gmail.com> wrote:
>
>
>
> > There is probably a better way to do this (please enlighten me, if you
> > know), but what I want to do is get a list of a class' attributes
> > minus whatever the 'builtin' methods are. ?I would also like to do
> > this for instances of classes as well. ?I don't want to use __dict__
> > because I want to get all of the attributes that have been added
> > throughout the inheritance tree, just not the builtin ones.
>
> > I was wondering if there is a function to return a list of these, so I
> > could perform a 'dir' on the object (class or instance) and filter out
> > the builtin attributes. ?I know I could create my own list something
> > like
> > ['__class__', '__delattr__', ..., '__weakref__'] and use that. ?I
> > would see this being fragile to Python version differences as new ones
> > are added or taken away.
>
> > A more flexible way is to have the list be filled out dynamically by
> > creating a 'junk' class that inherits only from object and storing
> > it's dir() output into the filter list. ?This is probably what I'll do
> > unless someone knows of a builtin function that will give me a
> > (version-safe) list.
>
> > Thanks!
>
> Haha, replying to my own post. ?Here is the implementation of my idea
> of dynamically creating the filter lists from a 'junk' object. ?As of
> now it appears that the dir output of a class is the same as the dir
> output of an instance, but if that ever changes, this should future
> proof it. ?This is only a 4-liner, so it is probably good enough for
> what I want to do, but I would rather use a builtin/standard way if
> there is one.
>
> class A(object):
> ? ? pass
> class_filter_methods = dir(A)
> instance_filter_methods = dir(A())

Wow, I'm a quick one. Sharp as a marble.  2-liner:

class_filter_methods = dir(object)
instance_filter_methods = dir(object())


From invalid at invalid  Wed Jul 22 14:49:58 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 22 Jul 2009 13:49:58 -0500
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
Message-ID: <P_ydnTKt2r_LwvrXnZ2dnUVZ_uSdnZ2d@posted.visi>

On 2009-07-22, Ron Garret <rNOSPAMon at flownet.com> wrote:
> In article <uRr9m.6558$ze1.5162 at news-server.bigpond.net.au>,
>  Neil Hodgson <nyamatongwe+thunder at gmail.com> wrote:
>
>> milanj:
>> 
>> > and all of them use native threads (python still use green threads ?)
>> 
>>    Python uses native threads.
>
> But then it adds the global interpreter lock, which completely 
> undermines the utility of native threads.  So yes, it uses native 
> threads, but it does not actually realize the benefits of that use.

Not all of the time. For library/extension calls that release
the GIL, it does.

-- 
Grant Edwards                   grante             Yow! I was making donuts
                                  at               and now I'm on a bus!
                               visi.com            


From http  Wed Jul 22 15:04:07 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 12:04:07 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
Message-ID: <7xfxco35g8.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> > Why is that such an advantage? ?Green threads work fine if you just
> > organize the i/o system to never block. ?
> 
> Because then I don't have to organize the I/O system never to block.

We're talking about what a language implementation does behind the
scenes, I thought.


From ethan at stoneleaf.us  Wed Jul 22 15:21:04 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 22 Jul 2009 12:21:04 -0700
Subject: Einstein summation notation
In-Reply-To: <7xprbybnso.fsf@ruckus.brouhaha.com>
References: <8bfce41e-719d-4d8b-bec8-bf341ea87e38@s9g2000yqd.googlegroups.com>	<687a86ae-244e-4c38-a11c-91e4d8eb92f6@g31g2000yqc.googlegroups.com>	<069f16b0-8c88-4b10-8fd0-59b35ea49a9c@i6g2000yqj.googlegroups.com>	<7x8wj4uxnb.fsf@ruckus.brouhaha.com>	<kmr2uu.d1t@spenarnc.xs4all.nl>	<Ts2dnZ3iTNgcTMLXnZ2dnUVZ_sidnZ2d@giganews.com>	<10acd98a-e1c9-4aca-bd20-0131277beec1@t11g2000prh.googlegroups.com>	<02701951$0$5185$c3e8da3@news.astraweb.com>	<7xljmnahlj.fsf@ruckus.brouhaha.com>	<02706d8f$0$5185$c3e8da3@news.astraweb.com>	<7xab33s8ik.fsf@ruckus.brouhaha.com>	<mailman.3290.1247847474.8015.python-list@python.org>
	<7xprbybnso.fsf@ruckus.brouhaha.com>
Message-ID: <4A6766A0.4000809@stoneleaf.us>

Paul Rubin wrote:
> Ethan Furman <ethan at stoneleaf.us> writes:
> 
>>Or if any(p for p in [header, body, footer, whatever, ...])
> 
> 
> No need for the genexp:
> 
>    if any([header, body, footer, whatever, ...])
> 
> But, you are using the built-in bool cast either way.

Right you are -- and

   if any([header, body, footer, whatever, ...])

sure looks nicer to me than your original code of

   if any(p != '' for p in [header, body, footer, otherthing1, ...])


But there a are a lot of decisions and factors to writing these things 
one way or the other.  I'm just glad Python supports the Something vs. 
Nothing model.

~Ethan~


From tjreedy at udel.edu  Wed Jul 22 15:24:19 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 22 Jul 2009 15:24:19 -0400
Subject: list of 'magic methods' or builtin class methods... want to
	exclude those from dir output
In-Reply-To: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
References: <7959c03f-d2d3-471e-a687-4695a09b3aa0@k13g2000prh.googlegroups.com>
Message-ID: <h47p12$rf7$1@ger.gmane.org>

DG wrote:
> There is probably a better way to do this (please enlighten me, if you
> know), but what I want to do is get a list of a class' attributes
> minus whatever the 'builtin' methods are.  I would also like to do
> this for instances of classes as well.  I don't want to use __dict__
> because I want to get all of the attributes that have been added
> throughout the inheritance tree, just not the builtin ones.
> 
> I was wondering if there is a function to return a list of these, so I
> could perform a 'dir' on the object (class or instance) and filter out
> the builtin attributes.  I know I could create my own list something
> like
> ['__class__', '__delattr__', ..., '__weakref__'] and use that.  I
> would see this being fragile to Python version differences as new ones
> are added or taken away.
> 
> A more flexible way is to have the list be filled out dynamically by
> creating a 'junk' class that inherits only from object and storing
> it's dir() output into the filter list.  This is probably what I'll do
> unless someone knows of a builtin function that will give me a
> (version-safe) list.
> 
> Thanks!
3.1
 >>> list(filter(lambda s: s[0:2]!='__', dir(object)))
[]

Now substitute your object for lambda. This assumes of course that you 
are doing no name-mangling __xxx names.

tjr




From pavlovevidence at gmail.com  Wed Jul 22 15:35:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 12:35:52 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
Message-ID: <f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>

On Jul 22, 12:04?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > > Why is that such an advantage? ?Green threads work fine if you just
> > > organize the i/o system to never block. ?
>
> > Because then I don't have to organize the I/O system never to block.
>
> We're talking about what a language implementation does behind the
> scenes, I thought.

No we're not, we are talking about the whether GIL completely or only
partially undermines the use of native threads on Python.

I don't think your fantasy async-only all-green-thread langauge
implementation is possible anyway.  How would you wait on a pipe in
one thread, a socket in another, a semaphore in a third?  (Are there
any popular OSes that offer a unified polling interface to all
possible synchronizations?)  And what do you do about drivers or
libraries that make underlying blocking calls?  What if you have a
busy calculation going on in the background?


Carl Banks


From robert.kern at gmail.com  Wed Jul 22 15:45:41 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 22 Jul 2009 14:45:41 -0500
Subject: clean way prepend an element to a numpy array
In-Reply-To: <7cnr5tF28183hU1@mid.individual.net>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>
	<7cnr5tF28183hU1@mid.individual.net>
Message-ID: <h47q96$158$1@ger.gmane.org>

On 2009-07-22 01:51, greg wrote:
> bdb112 wrote:
>
>> I saw this interest syntax on this site
>> x[:0]=0
>>
>> I guess that is cute, but could be confusing....(and doesn't work)
>
> It does if you use an array of the appropriate
> type on the right hand side:
>
> a[:0] = array('i', [0])

Not when 'a' is a numpy array rather than an array.array.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From torriem at gmail.com  Wed Jul 22 16:26:04 2009
From: torriem at gmail.com (Michael Torrie)
Date: Wed, 22 Jul 2009 14:26:04 -0600
Subject: GTK+ ques
In-Reply-To: <1e61b3260907220415g6edb24sb7fe07c83fe346c8@mail.gmail.com>
References: <1e61b3260907220415g6edb24sb7fe07c83fe346c8@mail.gmail.com>
Message-ID: <4A6775DC.1050003@gmail.com>

nipun batra wrote:
> I need to develop a GUI preferably in GTK using c or PYGTK.I have little
> idea about Python.
> Following are requiremnts of the application:
> should be GUI
> Sould be real time
> Should interface serial port
> should display moving maps,like google earth
> It is basically for Ground control station of a UAV.
> How would Python+Pygtk combo work?
> is python slower than c/c++ ,if then by how much?
> any suggestions for the applcation?

All of these things can be done in Python.  Using nice math libraries
like numpy, math-specific things can be very fast.  Whether python is
fast enough only you could say.  PyGTK is nice, but doesn't have
built-in primitives for doing super high level things like moving maps.
 But there are libraries out there that can do this, one of which is
call libchamplain.  A blog post about it is here:

http://blog.pierlux.com/2009/01/10/libchamplain-and-libchamplain-gtk-028-released/en/

libchamplain does have python bindings I think.


From george.sakkis at gmail.com  Wed Jul 22 16:27:13 2009
From: george.sakkis at gmail.com (George Sakkis)
Date: Wed, 22 Jul 2009 13:27:13 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
	<4a67421e$0$31038$426a74cc@news.free.fr>
Message-ID: <36aeca4d-0609-4da2-83a4-376c88869667@p23g2000vbl.googlegroups.com>

On Jul 22, 12:45?pm, William Dode <w... at flibuste.net> wrote:
> On 22-07-2009, George Sakkis wrote:
>
>
>
> > On Jul 22, 7:38?am, William Dode <w... at flibuste.net> wrote:
>
> >> I updated the script (python, c and java) with your unrolled version
> >> + somes litle thinks.
>
> >> I also tried with python3.1, unladen Q2, ironpython1.1.1
>
> >> Unfortunately it doesn't work more with shedskin, i'll see on the
> >> shedskin group...
>
> >> c 1.85s
> >> gcj 2.15s
> >> java 2.8s
> >> python2.5 + psyco 3.1s
> >> unladen-2009Q2 145s (2m45)
> >> python2.5 254s (4m14s)
> >> python3.1 300s (5m)
> >> ironpython1.1.1 680s (11m20)
>
> > Cool; it would be interesting to see the numbers for Jython and Boo as
> > well if it's not too much effort.
>
> I just tried with jython, but oddly it's faster without array.

FYI Jython 2.5 was released last month, you may want to try this
instead of 2.2.

George


From scriptlearner at gmail.com  Wed Jul 22 16:51:18 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Wed, 22 Jul 2009 13:51:18 -0700 (PDT)
Subject: logging outgoing HTTP POST message and incoming response message
Message-ID: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>

I am sending a HTTP POST by using the following codes:

opener = urllib2.build_opener(proxyHandler, MultipartPostHandler)
params = { "audio" : "http://sample.com/my.wav",
"data" : open(file, "rb") }
print opener.open(myURL, params).read()

How do I log or print out the actual POST message (including headers)
that is sent out?
How do I log or print out the response headers as well?

Thanks


From exarkun at divmod.com  Wed Jul 22 16:53:17 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Wed, 22 Jul 2009 16:53:17 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
Message-ID: <20090722205317.2543.659910647.divmod.quotient.4286@henry.divmod.com>

On Wed, 22 Jul 2009 12:35:52 -0700 (PDT), Carl Banks <pavlovevidence at gmail.com> wrote:
>On Jul 22, 12:04?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
>> Carl Banks <pavlovevide... at gmail.com> writes:
>> > > Why is that such an advantage? ?Green threads work fine if you just
>> > > organize the i/o system to never block.
>>
>> > Because then I don't have to organize the I/O system never to block.
>>
>> We're talking about what a language implementation does behind the
>> scenes, I thought.
>
>No we're not, we are talking about the whether GIL completely or only
>partially undermines the use of native threads on Python.
>
>I don't think your fantasy async-only all-green-thread langauge
>implementation is possible anyway.  How would you wait on a pipe in
>one thread, a socket in another, a semaphore in a third?  (Are there
>any popular OSes that offer a unified polling interface to all
>possible synchronizations?)

Every OS I can think of can support the three examples you gave here.

>And what do you do about drivers or
>libraries that make underlying blocking calls?

Certainly a point to consider.

>What if you have a busy calculation going on in the background?

What if you do?  Are you suggesting this would somehow prevent I/O from
being serviced?  I'm not sure why, as long as the implementation pays
attention to I/O events.

Jean-Paul


From deets at nospam.web.de  Wed Jul 22 16:54:02 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 22 Jul 2009 22:54:02 +0200
Subject: logging outgoing HTTP POST message and incoming response message
In-Reply-To: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
References: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
Message-ID: <7cpcjaF2915u5U1@mid.uni-berlin.de>

scriptlearner at gmail.com schrieb:
> I am sending a HTTP POST by using the following codes:
> 
> opener = urllib2.build_opener(proxyHandler, MultipartPostHandler)
> params = { "audio" : "http://sample.com/my.wav",
> "data" : open(file, "rb") }
> print opener.open(myURL, params).read()
> 
> How do I log or print out the actual POST message (including headers)
> that is sent out?
> How do I log or print out the response headers as well?

You can use proxy-tools such as tcpmon or sniff traffic using wireshark.

Diez


From scriptlearner at gmail.com  Wed Jul 22 17:18:37 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Wed, 22 Jul 2009 14:18:37 -0700 (PDT)
Subject: logging outgoing HTTP POST message and incoming response message
References: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
	<7cpcjaF2915u5U1@mid.uni-berlin.de>
Message-ID: <0b403bd0-759f-49b6-9eac-3d585d877fe3@k13g2000prh.googlegroups.com>

On Jul 22, 1:54?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> You can use proxy-tools such as tcpmon or sniff traffic using wireshark.
>
> Diez

Thanks,
but I am trying to enable some debug mode to log all outgoing and
incoming messages for certain period of time, and running another
proxy-tool is not very ideal.  It would be great to log it in some log
file.


From piet at cs.uu.nl  Wed Jul 22 17:24:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 23:24:34 +0200
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com>
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com>
	<16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com>
	<524a57a9-ba45-459b-b62d-81f527888a4e@j19g2000vbp.googlegroups.com>
Message-ID: <m2k520l8bx.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:

>d> i never heard of the logging module, but this function seemed simple
>d> enough.

>d> i assume this link is what you refering to:
>d> http://docs.python.org/library/logging.html

>d> thanks for the helpful info. i think "Piet van Oostrum" has resolved
>d> my issue. good eyes!

Without glasses I wouldn't have noticed it :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul 22 17:50:03 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 22 Jul 2009 23:50:03 +0200
Subject: Issue combining gzip and subprocess
References: <mailman.3472.1248192725.8015.python-list@python.org>
	<m2eisam153.fsf@cs.uu.nl>
	<2YednUGQxvntgfrXnZ2dnUVZ_hWdnZ2d@pdx.net>
Message-ID: <m2fxcol75g.fsf@cs.uu.nl>

>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) schreef:

>SDD> Piet van Oostrum wrote:
>>> ...
>>> f = gzip.open(filename, 'w')
>>> proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
>>> while True:
>>> line = proc.stdout.readline()
>>> if not line: break
>>> f.write(line)
>>> f.close()

>SDD> Or even:
>SDD>     proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
>SDD>     with gzip.open(filename, 'w') as dest:
>SDD>         for line in iter(proc.stdout, ''):
>SDD>             f.write(line)

If it would work.

1) with gzip... is not supported in Python < 3.1
2) for line in iter(proc.stdout), i.e. no second argument.
3) dest <==> f should be the same identifier.

Lesson: if you post code either: 
- test it and copy verbatim from your test, or
- write a disclaimer 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul 22 18:17:12 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 00:17:12 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
References: <mailman.3540.1248276934.8015.python-list@python.org>
Message-ID: <m2bpncl5w7.fsf@cs.uu.nl>

>>>>> Krishnakant <hackingkk at gmail.com> (K) wrote:

>K> hello all,
>K> This is a real challenge and I don't know if a solution even exists for
>K> this or not.

>K> I am writing an application which I run as my usual user on ubuntu.
>K> the usernake is let's say kk and it has sudo permission (meaning the
>K> user is in the sudoers list ).


>K> now when i do python myscript.py, the script has to change to another
>K> non-privileged user for some tasks.
>K> let's say for example switch to the postgres user which is dedicated for
>K> postgres and has no other privileges.

>K> I have tryed doing os.setuid(112) where 112 could be the uid of the user
>K> I want the script to swith over.

>K> but I got opperation not permitted.

Being a sudoer is not a privilege to issue the os.setuid system call. It
is only a permission to use the sudo command.

>K> I tryed using subprocess but that did not help me either.  I tryed sudo
>K> su into the Popen command but it throws me into the terminal (shell)
>K> with postgres as the user.

You could execute the command:
sudo -u postgres required_command
with subprocess.

You have another problem then: your password must be supplied unless the
NOPASSWD flag is set in the sudoers file.

>K> But that's now my desired result.
>K> what I exactly want is that the script now continues to execute under
>K> postgres user till the end.

I don't think that's possible if you start as the user kk. 

>K> I don't know how to achieve this iffect.

>K> Infact I will need this during a serious deployment because i would have
>K> my application run as a demon as a dedicated user.

>K> I am finding some code for deamonising a python application but don't
>K> know how to tell the script to change user.

>K> happy hacking.
>K> Krishnakant.



-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From pavlovevidence at gmail.com  Wed Jul 22 18:17:52 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 22 Jul 2009 15:17:52 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
Message-ID: <64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>

On Jul 22, 1:53?pm, Jean-Paul Calderone <exar... at divmod.com> wrote:
> On Wed, 22 Jul 2009 12:35:52 -0700 (PDT), Carl Banks <pavlovevide... at gmail.com> wrote:
> >On Jul 22, 12:04?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> >> Carl Banks <pavlovevide... at gmail.com> writes:
> >> > > Why is that such an advantage? ?Green threads work fine if you just
> >> > > organize the i/o system to never block.
>
> >> > Because then I don't have to organize the I/O system never to block.
>
> >> We're talking about what a language implementation does behind the
> >> scenes, I thought.
>
> >No we're not, we are talking about the whether GIL completely or only
> >partially undermines the use of native threads on Python.
>
> >I don't think your fantasy async-only all-green-thread langauge
> >implementation is possible anyway. ?How would you wait on a pipe in
> >one thread, a socket in another, a semaphore in a third? ?(Are there
> >any popular OSes that offer a unified polling interface to all
> >possible synchronizations?)
>
> Every OS I can think of can support the three examples you gave here.

I guess you would know, but polling on all of these at once has got
use more obscure calls than I'm familiar with.

On Linux I can use select to wait for pipes and sockets, but not SysV
semaphores AFAIK.  On Windows it's well known that select only works
for sockets.

So do all these OSes have some kind of __mega_unifying_poll system
call that works for anything that might possibly block, that you can
exploit from a user process?


> >And what do you do about drivers or
> >libraries that make underlying blocking calls?
>
> Certainly a point to consider.
>
> >What if you have a busy calculation going on in the background?
>
> What if you do? ?Are you suggesting this would somehow prevent I/O from
> being serviced? ?I'm not sure why, as long as the implementation pays
> attention to I/O events.

Using native theads with blocking allows one to run a background
calculation without burdening it to yield often enough to provide
sufficient response times for other operations (which may or may not
be convenient to do).

Even if it's possible to accomplish arbitrary background processing
without native threading (and it is not, because the background
calculations could be performed by a library you don't control whose
author didn't bother yielding at any point), you cannot reasonably
claim native threads have no advantage in this case.


Carl Banks


From ethan at stoneleaf.us  Wed Jul 22 18:35:01 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Wed, 22 Jul 2009 15:35:01 -0700
Subject: Changing the private variables content
In-Reply-To: <4A671BAF.1060204@gmail.com>
References: <mailman.13388.1248268320.8014.python-list@python.org>
	<4A671BAF.1060204@gmail.com>
Message-ID: <4A679415.90407@stoneleaf.us>

Ryniek90 wrote:
>>
>> Got it:
>>
>> exec('self.' + attr + '=\'' + val + '\'')
>>
>> That worked. I think it'll do what you want now ;)
>>
>> Ching-Yun "Xavier" Ho, Technical Artist
>>
>> Contact Information
>> Mobile: (+61) 04 3335 4748
>> Skype ID: SpaXe85
>> Email: contact at xavierho.com <mailto:contact at xavierho.com>
>> Website: http://xavierho.com/
> 
> 
> To bad, that didn't worked in my class. Still the same error:
> "
>  >>> mod.print_module('socket')
> 
> Traceback (most recent call last):
>  File "<pyshell#121>", line 1, in <module>
>    mod.print_module('socket')
>  File "<pyshell#118>", line 51, in print_module
>    module_open = open(self._this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> :-/
> 
>> What is the point of the _SetVar method?
>>
>> Instead of:
>>
>>     self._SetVar(self._this_module, os.path.join(root, f))
>>
>> just do:
>>
>>     self._this_module = os.path.join(root, f)
>>
>> (unless I'm misunderstanding what you're trying to do!)
>>
> 
> Of course i;ve tried, but still get the same error:
> 
> "
>  >>> mod.print_module('socket')
> 
> Traceback (most recent call last):
>  File "<pyshell#121>", line 1, in <module>
>    mod.print_module('socket')
>  File "<pyshell#118>", line 51, in print_module
>    module_open = open(self.this_module, 'rb')
> IOError: [Errno 2] No such file or directory: ''
>  >>>
> "
> 
> It looks like private variable have specific naure, that prevent from 
> traditional editing them.
> Still searching for some tuts about private methods and variables.

No.  There is nothing special about variables with a leading underscore.

_number

is treated by Python *exactly* the same as

number

.  The specific problem in your code above is your _SetVar function, 
among the more general problem of not yet having a good understanding of 
classes in Python.  Keep studying, Python is an awesome language.

I was able to make this work -- hope it helps.

8<-----------------------------------------------------------------------
import os
import sys

class ModPrint(object):
     u"""This will be the doc."""
     def __init__(self):
         self._default_search_path = sys.exec_prefix

     def _search_for_module(self, chosen_module, search_path):
         for root, dirs, files in os.walk(search_path):
             for f in files:
                 if f == ("%s.py" % chosen_module):
                     return os.path.join(root, f)

     def print_module(self, chosen_module, user_search_path=''):
         search_path = user_search_path or self._default_search_path
         module = self._search_for_module(chosen_module, search_path)
         if module is not None:
             module_open = open(module, 'rb')
             module_text = module_open.read()
             module_open.close()
             return module_text
         return 'Module not found...'
8<-----------------------------------------------------------------------


From pinkeen at gmail.com  Wed Jul 22 18:43:08 2009
From: pinkeen at gmail.com (Filip)
Date: Wed, 22 Jul 2009 15:43:08 -0700 (PDT)
Subject: python fast HTML data extraction library
Message-ID: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>

Hello,

Sometime ago I was searching for a library that would simplify mass
data scraping/extraction from webpages. Python XPath implementation
seemed like the way to go. The problem was that most of the HTML on
the net doesn't conform to XML standards, even the XHTML (those
advertised as valid XHTML too) pages.

I tried to fix that with BeautifulSoup + regexp filtering of some
particular cases I encountered. That was slow and after running my
data scraper for some time a lot of new problems (exceptions from
xpath parser) were showing up. Not to mention that BeautifulSoup
stripped almost all of the content from some heavily broken pages
(50+KiB page stripped down to some few hundred bytes). Character
encoding conversion was a hell too - even UTF-8 pages had some non-
standard characters causing issues.


Cutting to the chase - that's when I decided to take the matter into
my own hands. I hacked together a solution sporting completely new
approach overnight. It's called htxpath - a small, lightweight (also
without dependencies) python library which lets you to extract
specific tag(s) from a HTML document using a path string which has
very similar syntax to xpath (but is more convenient in some cases).
It did a very good job for me.

My library, rather than parsing the whole input into a tree, processes
it like a char stream with regular expressions.

I decided to share it with everyone so there it is: http://code.google.com/p/htxpath/
I am aware that it is not beautifully coded as my experience with
python is rather brief, but I am curious if it will be useful to
anyone (also it's my first potentially [real-world ;)] useful project
gone public). In that case I promise to continue developing it. It's
probably full of bugs, but I can't catch them all by myself.

regards,
Filip Sobalski


From ben+python at benfinney.id.au  Wed Jul 22 19:26:37 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 23 Jul 2009 09:26:37 +1000
Subject: Documentation Problems
References: <h46rpv$lm5$1@adenine.netfront.net>
	<mailman.3518.1248261276.8015.python-list@python.org>
	<b15bebec-eb4a-4ea0-b05e-d62d5c707f3f@s31g2000yqs.googlegroups.com>
Message-ID: <87ocrc7102.fsf@benfinney.id.au>

Inky 788 <inky788 at gmail.com> writes:

> Could you please provide brief instructions on exactly how to go about
> creating a suitable patch file? I mean, starting from the beginning
> (as in, "check out code from {here} using {this command}", "cd to
> {this} directory", "edit the file in place", "run {this} command to
> create a patch file"). Or perhaps this procedure is already outlined
> elsewhere?

Yes. The documentation is built from source documents under version
control, like the rest of Python. So the procedure for creating and
submitting patches is the same, and is covered by the Developer's FAQ
<URL:http://www.python.org/dev/faq/>.

-- 
 \           ?If you ever fall off the Sears Tower, just go real limp, |
  `\     because maybe you'll look like a dummy and people will try to |
_o__)                catch you because, hey, free dummy.? ?Jack Handey |
Ben Finney


From piet at cs.uu.nl  Wed Jul 22 19:34:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 01:34:34 +0200
Subject: Changing the private variables content
References: <mailman.13388.1248268320.8014.python-list@python.org>
	<mailman.3534.1248271304.8015.python-list@python.org>
Message-ID: <m27hy0l2b9.fsf@cs.uu.nl>

>>>>> Ryniek90 <ryniek90 at gmail.com> (R) wrote:

>R> It looks like private variable have specific naure, that prevent from
>R> traditional editing them.
>R> Still searching for some tuts about private methods and variables.

Why do you stubbornly keep saying that, while you have been told that it
is not the case. Instead you would do better debugging your own case
instead of making false claims. Sprinkle a few print statements in your
code to see what is happening.

Here are a few thing for you to look at:

       #using private method '_search_for_module' with 'self.' prefix
       #to search for prefered module
       self._search_for_module(_chosen_module, _user_search_path)

You call it with 2 parameters: _chosen_module, _user_search_path
Look at the definition:

   def _search_for_module(self, *args):

It has *args to pick up the arguments, but they are not used in the
body. Instead you use self._user_search_path and self._chosen_module.
The latter one is always '', never changed to anything else. So it is
not surprising that the module is not found.
 
In print_module you have the same kind of confusion.

Do you think that magically self._chosen_module gets the value of
_chosen_module? Is that you idea of `private variables'?

Or do you think that *args does magical things?

       """Private method which walks through default Python
       installation directories, and search for prefered module."""
           #walking thru all directories available in path _user_search_path'
       for root, dirs, files in os.walk(self._user_search_path):
           for f in files:
               #if found file 'f' is THAT module,
               #full path to THAT file is assigned to variable
               print "Trying %s" % f
               if f == ("%s.py" % self._chosen_module):
                   self._this_module = os.path.join(root, f)


-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Wed Jul 22 19:36:38 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 01:36:38 +0200
Subject: Python-list Digest, Vol 70, Issue 282
References: <mailman.13395.1248271304.8014.python-list@python.org>
	<mailman.3544.1248279076.8015.python-list@python.org>
Message-ID: <m23a8ol27t.fsf@cs.uu.nl>

>>>>> Ryniek90 <ryniek90 at gmail.com> (R) wrote:

>R> "
>R> Didn't worked, so i wil reuse your class, and modify it later. Now i see
>R> that working on private objects complex.

No it's not complex. *You* make it complex.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From Brian.Mingus at colorado.edu  Wed Jul 22 19:51:52 2009
From: Brian.Mingus at colorado.edu (Brian)
Date: Wed, 22 Jul 2009 17:51:52 -0600
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
In-Reply-To: <4a675296$0$1549$426a74cc@news.free.fr>
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<10ef7849-a1ea-4770-b8c8-6f7bd2594579@g23g2000vbr.googlegroups.com>
	<4a67421e$0$31038$426a74cc@news.free.fr>
	<4a675296$0$1549$426a74cc@news.free.fr>
Message-ID: <9839a05c0907221651o6afaa80xc25f37ff9bcbeea5@mail.gmail.com>

On Wed, Jul 22, 2009 at 11:55 AM, William Dode <wilk at flibuste.net> wrote:

> On 22-07-2009, William Dode wrote:
>
> > c 1.65s
> > gcj 1.9s
> > java 2.4s
> > python2.5 + psyco 2.9s
> > shedskin 3.4s
>
> with -bw i have 2.6s
>
> > unladen-2009Q2 125s (2m05)
> > Jython 2.2.1 on java1.6.0_12 176s (without array, like shedskin)
> > Jython 2.2.1 on java1.6.0_12 334s (with array)
> > python2.5 215s (3m35s)
> > python3.1 246s (4m06s)
> > ironpython1.1.1 512 (8m32s)
>
> somebody can test with ironpython on windows ?
>
> Anyway, it's very impressive. I wonder if unladen will be so close in
> the futur.
>
> --
> William Dod? - http://flibuste.net
> Informaticien Ind?pendant
>

I had time to run a few tests. Since psyco doesn't work on 64 bit and the
developer now works on pypy I used that.

Intel Core i7 920 @ 2.66GHz
Kubuntu Jaunty Jackal

c gcc    4.3.3 0.77s
gcj      4.3.3 0.81s
java     1.6   0.99s
shedskin       1.63s
jython   2.2.1 85.37s
cpython  2.6.2 93.26s
pypy     1.1.0 1612.15s

 <http://mail.python.org/mailman/listinfo/python-list>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/3d82420a/attachment-0001.html>

From gagsl-py2 at yahoo.com.ar  Wed Jul 22 19:52:06 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 20:52:06 -0300
Subject: Detect target name in descriptor __set__ method
References: <mailman.3504.1248238988.8015.python-list@python.org>
	<3cb5f960-16f7-4fc6-841f-d0706f0e1d0a@s31g2000yqs.googlegroups.com>
Message-ID: <op.uxhtw4x8x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 05:31:13 -0300, Jon Clements <joncle at googlemail.com>  
escribi?:
> On 22 July, 06:02, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:

>> I have a class attribute 'foo' which is a data descriptor. I create an ?
>> instance of such class. When I say instance.foo = value, the descriptor  
>> ?
>> __set__ method is called. Is there any way to obtain the name being ?
>> assigned to? ('foo' in this example). That is, I want to know the  
>> target ?
>> name for the assignment that triggered the __set__ method call.

>>>> class Test:
> 	def __setattr__(self, what, value):
> 		print what, value
>
>
>>>> t = Test()
>>>> t.foo = 'x'
> foo x
>
> Is that what you're after?

Yes and no. __setattr__ has a terrible overhead as it is invoked for each  
and every attribute being set, special or not. Using a custom descriptor  
seems better, because it allows to intercept just the desired attribute.  
If only I had access to the name being used...

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Wed Jul 22 20:05:55 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 21:05:55 -0300
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst>
Message-ID: <op.uxhuj5olx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James  
<rhodri at wildebst.demon.co.uk> escribi?:
> On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina  
> <gagsl-py2 at yahoo.com.ar> wrote:
>
>
>> class X(object):
>>    foo = descriptor()
>>
>> x = X()
>> x.foo = "value"
>
> Isn't this going to create a brand new instance attribute x.foo that has  
> nothing to do with the descriptor anyway?

No, it's up to the descriptor __set__ method what happens in this case.  
Think of the standard 'property' descriptor, the fset function can do  
whatever it wants.
Also, a data descriptor takes precedence over any instance attribute of  
the same name that might exist.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Wed Jul 22 20:10:54 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 22 Jul 2009 21:10:54 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<02701d35$0$5185$c3e8da3@news.astraweb.com>
	<CVl8m.141$MA3.16@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
	<EgE9m.507$646.499@nwrddc01.gnilink.net>
Message-ID: <op.uxhusgo9x6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 10:14:12 -0300, Alan G Isaac <alan.isaac at gmail.com>  
escribi?:

>>>> On Fri, 17 Jul 2009 05:19:50 +0000, Alan G Isaac wrote:
>>>>> def apply2(itr, methodname, *args, **kwargs):
>>>>>     f = operator.methodcaller(methodname, *args, **kwargs)
>>>>>     for item in itr:
>>>>>         f(item)
>
>
>>> On 7/17/2009 3:45 AM Steven D'Aprano apparently wrote:
>>>> for obj in objects:
>>>>     getattr(obj, methodname)(*args, **kwargs)
>
>
>> En Sat, 18 Jul 2009 12:31:46 -0300, Alan G Isaac:
>>> Are there any obvious considerations in choosing
>>> between those two?
>
>
> On 7/20/2009 3:29 AM Gabriel Genellina apparently wrote:
>> The operator.methodcaller version is faster in my tests for large
>> collections, but slightly slower when you have very few elements.
>
>
> So it seems.  Is this easily explained?

NLMPI

-- 
Gabriel Genellina



From martin.hellwig at dcuktec.org  Wed Jul 22 20:22:14 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 23 Jul 2009 01:22:14 +0100
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <mailman.3540.1248276934.8015.python-list@python.org>
References: <mailman.3540.1248276934.8015.python-list@python.org>
Message-ID: <Y7GdnVBIVrqqMPrXnZ2dnUVZ8gWdnZ2d@bt.com>

Krishnakant wrote:
<cut elevate/dropdown rights problem>

I've seen a method before in a MS cmd script (MakeMeAdmin.cmd) for the 
purpose of temporarily elevating your rights but remaining the same user.

There was a need trick in that the script checks itself on what 
credentials it runs, if it is not the appropriate one it will call 
itself again with runas (about the same as sudo) and exits.

If it has the right credentials it will perform the actual task.

That might be a way to solve your problem.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From http  Wed Jul 22 20:27:23 2009
From: http (Paul Rubin)
Date: 22 Jul 2009 17:27:23 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
Message-ID: <7xws60p7kk.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> I don't think your fantasy async-only all-green-thread langauge
> implementation is possible anyway. 

Erlang and GHC both work like that, quite successfully:

  http://shootout.alioth.debian.org/gp4/benchmark.php?test=threadring&lang=all

> How would you wait on a pipe in one thread, a socket in another, a
> semaphore in a third?  

You can select on pipes and sockets, I think.  Not sure about
semaphores.  

> (Are there any popular OSes that offer a unified polling interface to
> all possible synchronizations?)  And what do you do about drivers or
> libraries that make underlying blocking calls?  What if you have a
> busy calculation going on in the background?

I don't think the concept of "drivers" applies to user-mode programs.
For FFI calls you would use an OS thread.  The language runtime
switches between busy computation threads on a timer tick.


From wells at submute.net  Wed Jul 22 20:40:11 2009
From: wells at submute.net (Wells Oliver)
Date: Wed, 22 Jul 2009 19:40:11 -0500
Subject: RPY2 examples?
Message-ID: <3f1a902d0907221740i62487600xc2210ca9fede5791@mail.gmail.com>

I am trying to find examples using RPY2 to render R graphs to PNG/PDF/etc.
The only things I can find use rpy 1.x. Any references? Thanks!

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/56bfd645/attachment-0001.html>

From kwmsmith at gmail.com  Wed Jul 22 21:25:17 2009
From: kwmsmith at gmail.com (Kurt Smith)
Date: Wed, 22 Jul 2009 21:25:17 -0400
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
In-Reply-To: <861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
	<861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
Message-ID: <c266a7930907221825y4c1c4a26g1549e7308355b9dc@mail.gmail.com>

On Wed, Jul 22, 2009 at 2:48 AM, Bearophile<bearophileHUGS at lycos.com> wrote:
> greg:
>> Posting benchmark times for Pyrex or Cython is pretty
>> meaningless without showing the exact code that was
>> used, since times can vary enormously depending on
>> how much you C-ify things.
>
> Was this link, shown by William, not enough?
> http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1

I took a stab at converting the recent psyco-optimized code to cython,
and got a speedup.

gcj    4.3.3    1.39s
gcc    4.3.3    1.55s
cython 11.2     1.91s
psyco           1.94s
javac  1.5.0_19 2.00s
python 2.5.4    168.37s

It was just a matter of cdef-ing all the arrays & integers --
bearophile already did the hard work :-)

Here's the cython code; all the others are from the repo.

#################################################
DEF NMOVES = 8
DEF SIDE = 5
DEF SQR_SIDE = SIDE * SIDE

cdef int circuit[SQR_SIDE]
cdef int nsolutions = 0

cdef int movex[NMOVES]
cdef int movey[NMOVES]
py_movex = [-1,-2,-2,-1,+1,+2,+2,+1]
py_movey = [-2,-1,+1,+2,+2,+1,-1,-2]
for i in range(NMOVES):
   movex[i] = py_movex[i]
   movey[i] = py_movey[i]
shift = [x * SIDE + y for x,y in zip(py_movex, py_movey)]
cdef int shift_0 = shift[0]
cdef int shift_1 = shift[1]
cdef int shift_2 = shift[2]
cdef int shift_3 = shift[3]
cdef int shift_4 = shift[4]
cdef int shift_5 = shift[5]
cdef int shift_6 = shift[6]
cdef int shift_7 = shift[7]

def showCircuit():
   print
   for x in xrange(SIDE):
       x_SIDE = x * SIDE
       for y in xrange(SIDE):
           if SQR_SIDE < 100:
               print "%02d " % circuit[x_SIDE + y],
           else:
               print "%03d " % circuit[x_SIDE + y],
       print

cdef void solve(int nb, int x, int y,
       int SIDE=SIDE, int SQR_SIDE=SQR_SIDE, int *circuit=circuit,
       int shift_0=shift_0,
       int shift_1=shift_1,
       int shift_2=shift_2,
       int shift_3=shift_3,
       int shift_4=shift_4,
       int shift_5=shift_5,
       int shift_6=shift_6,
       int shift_7=shift_7,
       ):
   global nsolutions

   cdef int newx, newy
   cdef int pos = x * SIDE + y
   circuit[pos] = nb
   if nb == SQR_SIDE:
       #showCircuit()
       nsolutions += 1
       circuit[pos] = 0
       return

   newx = x + -1
   if newx >= 0 and newx < SIDE:
       newy = y + -2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_0]:
           solve(nb+1, newx, newy)

   newx = x + -2
   if newx >= 0 and newx < SIDE:
       newy = y + -1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_1]:
           solve(nb+1, newx, newy)

   newx = x + -2
   if newx >= 0 and newx < SIDE:
       newy = y + 1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_2]:
           solve(nb+1, newx, newy)

   newx = x + -1
   if newx >= 0 and newx < SIDE:
       newy = y + 2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_3]:
           solve(nb+1, newx, newy)

   newx = x + 1
   if newx >= 0 and newx < SIDE:
       newy = y + 2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_4]:
           solve(nb+1, newx, newy)

   newx = x + 2
   if newx >= 0 and newx < SIDE:
       newy = y + 1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_5]:
           solve(nb+1, newx, newy)

   newx = x + 2
   if newx >= 0 and newx < SIDE:
       newy = y + -1
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_6]:
           solve(nb+1, newx, newy)

   newx = x + 1
   if newx >= 0 and newx < SIDE:
       newy = y + -2
       if newy >= 0 and newy < SIDE and not circuit[pos + shift_7]:
           solve(nb+1, newx, newy)

   circuit[pos] = 0

def main():
   print "Search for side=%d" % SIDE
   cdef int x,y
   for x in range(SIDE):
       for y in range(SIDE):
           solve(1, x, y);
   print "\n%dx%d case, %d solutions." % (SIDE, SIDE, nsolutions)

def run():
   import time
   s=time.time()
   main()
   print time.time()-s
#################################################


From scriptlearner at gmail.com  Wed Jul 22 21:45:45 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Wed, 22 Jul 2009 18:45:45 -0700 (PDT)
Subject: regex: multiple matching for one string
Message-ID: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>

For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
will like to take out the values (valuea, valueb, and valuec).  How do
I do that in Python?  The group method will only return the matched
part.  Thanks.

p = re.compile('#a=*;b=*;c=*;')
m = p.match(line)
        if m:
             print m.group(),


From ptmcg at austin.rr.com  Wed Jul 22 21:53:33 2009
From: ptmcg at austin.rr.com (Paul McGuire)
Date: Wed, 22 Jul 2009 18:53:33 -0700 (PDT)
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
Message-ID: <88e8ea19-7106-406a-a531-88c2b6893987@y7g2000yqa.googlegroups.com>

On Jul 22, 5:43?pm, Filip <pink... at gmail.com> wrote:
>
> My library, rather than parsing the whole input into a tree, processes
> it like a char stream with regular expressions.
>

Filip -

In general, parsing HTML with re's is fraught with easily-overlooked
deviations from the norm.  But since you have stepped up to the task,
here are some comments on your re's:

# You should use raw string literals throughout, as in:
# blah_re = re.compile(r'sljdflsflds')
# (note the leading r before the string literal).  raw string
literals
# really help keep your re expressions clean, so that you don't ever
# have to double up any '\' characters.

# Attributes might be enclosed in single quotes, or not enclosed in
any quotes at all.
attr_re = re.compile('([\da-z]+?)\s*=\s*\"(.*?)\"', re.DOTALL |
re.UNICODE | re.IGNORECASE)

# Needs re.IGNORECASE, and can have tag attributes, such as <BR
CLEAR="ALL">
line_break_re = re.compile('<br\/?>', re.UNICODE)

# what about HTML entities defined using hex syntax, such as &#xxxx;
amp_re = re.compile('\&(?![a-z]+?\;)', re.UNICODE | re.IGNORECASE)

How would you extract data from a table?  For instance, how would you
extract the data entries from the table at this URL:
http://tf.nist.gov/tf-cgi/servers.cgi ?  This would be a good example
snippet for your module documentation.

Try extracting all of the <a href=...>sldjlsfjd</a> links from
yahoo.com, and see how much of what you expect actually gets matched.

Good luck!

-- Paul


From rurpy at yahoo.com  Wed Jul 22 22:00:42 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Wed, 22 Jul 2009 19:00:42 -0700 (PDT)
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
Message-ID: <a7445b44-6518-4180-afe0-d20a246ce161@h18g2000yqj.googlegroups.com>

On Jul 22, 7:45 pm, "scriptlear... at gmail.com"
<scriptlear... at gmail.com> wrote:
> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
> will like to take out the values (valuea, valueb, and valuec).  How do
> I do that in Python?  The group method will only return the matched
> part.  Thanks.
>
> p = re.compile('#a=*;b=*;c=*;')
> m = p.match(line)
>         if m:
>              print m.group(),

p = re.compile('#a=([^;]*);b=([^;]*);c=([^;]*);')
m = p.match(line)
if m:
    print m.group(1),m.group(2),m.group(3),

Note that "=*;" in your regex will match
zero or more "=" characters -- probably not
what you intended.

"[^;]* will match any string up to the next
";" character which will be a value (assuming
you don't have or care about embedded whitespace.)

You might also want to consider using a r'...'
string for the regex, which will make including
backslash characters easier if you need them
at some future time.


From wuwei23 at gmail.com  Wed Jul 22 22:04:34 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 22 Jul 2009 19:04:34 -0700 (PDT)
Subject: Ideas for problem with chat server application!
References: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
Message-ID: <40c22282-7526-4064-8885-62a87107bb3d@p10g2000prm.googlegroups.com>

On Jul 22, 6:27?pm, "David Adamo Jr." <dtgead... at yahoo.com> wrote:
> Suggestions are highly appreciated.

I haven't used it but I've heard good things about FireDaemon, which
can run any script or program as a Windows service.

Apparently the Lite version is free:
http://www.download-freeware-shareware.com/Freeware-System-Utilities.php?Type=14387

Hope this helps.



From cindy at speed-voip.com  Wed Jul 22 22:36:31 2009
From: cindy at speed-voip.com (cindy)
Date: Wed, 22 Jul 2009 22:36:31 -0400
Subject: [Unblocking VoIP in UAE] for freedom!
Message-ID: <e044bbf877a62d09a89e8b12438141c0@localhost.localdomain>

Please view this newsletter online at:
http://www.mynewsletterbuilder.com/tools/view_newsletter.php?newsletter_id=1409985533
SpeedVoIP Communication Technology Co., LTD. - 600, 6th Avenue S.W. - Calgary
- Alberta - T2P 0S5

Subscribe to this newsletter:
https://www.mynewsletterbuilder.com/tools/subscription.php?username=svsales&send_id=712043215&l=s&newsletter_id=1409985533
Unsubscribe python-list at python.org:
https://www.mynewsletterbuilder.com/tools/subscription.php?username=svsales&send_id=712043215&l=u&email=python-list at python.org
Change your preferences:
https://www.mynewsletterbuilder.com/tools/subscription.php?username=svsales&send_id=712043215&l=p&email=python-list at python.org
Forward to a friend:
http://www.mynewsletterbuilder.com/tools/forward.php?username=svsales&newsletter_id=1409985533&email=python-list at python.org&send_id=712043215
Report this email as spam:
https://www.mynewsletterbuilder.com/tools/abuse_report.php?username=svsales&send_id=712043215&email=python-list at python.org

This email was sent using MyNewsletterBuilder.com.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090722/0cc8e817/attachment-0001.html>

From songofacandy at gmail.com  Wed Jul 22 23:06:56 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Wed, 22 Jul 2009 20:06:56 -0700 (PDT)
Subject: What is file.encoding convention?
Message-ID: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>

In document <http://docs.python.org/library/
stdtypes.html#file.encoding>:

>> The encoding that this file uses. When Unicode strings are written to a file,
>>  they will be converted to byte strings using this encoding. In addition,
>> when the file is connected to a terminal, the attribute gives the encoding
>> that the terminal is likely to use

But in logging.StreamHandler.emit() ::

                try:
                    if (isinstance(msg, unicode) and
                        getattr(stream, 'encoding', None)):
                        #fs = fs.decode(stream.encoding)
                        try:
                            stream.write(fs % msg)
                        except UnicodeEncodeError:
                            #Printing to terminals sometimes fails.
For example,
                            #with an encoding of 'cp1251', the above
write will
                            #work if written to a stream opened or
wrapped by
                            #the codecs module, but fail when writing
to a
                            #terminal even when the codepage is set to
cp1251.
                            #An extra encoding step seems to be
needed.
                            stream.write((fs % msg).encode
(stream.encoding))
                    else:
                        stream.write(fs % msg)
                except UnicodeError:
                    stream.write(fs % msg.encode("UTF-8"))

And behavior of sys.stdout in Windows::
>>> import sys
>>> sys.stdout.encoding
'cp932'
>>> u = u"???"
>>> u
u'\u3042\u3044\u3046'
>>> print >>sys.stdout, u
???
>>> sys.stderr.write(u)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode characters in position
0-2: ordinal not in range(128)


What is file.encoding convention?
If I want to write a unicode string to a file(-like) that have
encoding attribute, I should do
(1) try: file.write(unicode_str),
(2) except UnicodeEncodeError: file.write(unicode_str.encode
(file.encoding))
like logging?
It seems agly.


From sjmachin at lexicon.net  Wed Jul 22 23:24:47 2009
From: sjmachin at lexicon.net (John Machin)
Date: Wed, 22 Jul 2009 20:24:47 -0700 (PDT)
Subject: Not understanding this documentation
References: <25704c70-b9c6-4435-9ff0-9659bd340847@x25g2000prf.googlegroups.com>
	<mailman.3538.1248275284.8015.python-list@python.org>
	<081d1a50-fd7f-4f87-889e-262bc7e2debd@x5g2000prf.googlegroups.com>
Message-ID: <c20222ea-6258-403b-b2fa-707df898aff7@d4g2000prc.googlegroups.com>

On Jul 23, 2:45?am, "F.O.P." <f.orndorffplunk... at gmail.com> wrote:
> On Jul 22, 9:07?am, "Rhodri James" <rho... at wildebst.demon.co.uk>
> wrote:
>
>
>
>
>
>
>
> > On Wed, 22 Jul 2009 15:46:09 +0100, F.O.P. <f.orndorffplunk... at gmail.com> ?
> > wrote:
>
> > >http://bugs.python.org/issue5358
> > > I simply installed 3.0 on my ubuntubox brought my project from a
> > > windows machine and made necessary changes to what I had used from os
> > > and os.path. ?I have an error at the end of this line:
> > > for k in range(I):
> > > and the error:
> > > SyntaxError: invalid character in identifier
>
> > > I've already declared I way above as the lenth of an array (I = len
> > > (IA))
> > > There shouldn't be a problem there aren't any issues with other
> > > declarations identical to this.
>
> > Could you show us slightly more of your code and the rest of the
> > error message, please? ?I have a suspicion that the error actually
> > lies in the "necessary changes" you made.
>
> > --
> > Rhodri James *-* Wildebeest Herder to the Masses
>
> I spoke to a friend about it and he found that I had put in a unicode
> "semicolon" rather than ASCII.

This is rather puzzling. What are you describing as a "unicode
semicolon"? Possibilities include:

(a) U+003B SEMICOLON (which is exactly what you need)
(b) U+037E GREEK QUESTION MARK (which looks like (a))
(c) U+061B ARABIC SEMICOLON (which looks like (a) rotated 180 degrees)

How did you get it into your source file?

What was in your
# coding: ?????
or similar line at the top of your source file?


From aahz at pythoncraft.com  Wed Jul 22 23:38:30 2009
From: aahz at pythoncraft.com (Aahz)
Date: 22 Jul 2009 20:38:30 -0700
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com>
Message-ID: <h48lvm$qau$1@panix3.panix.com>

In article <f3d88edf-b5d3-43e4-89a3-b05ef0f55b47 at p28g2000vbn.googlegroups.com>,
Carl Banks  <pavlovevidence at gmail.com> wrote:
>
>You have to be REALLY REALLY careful not to pass any user-supplied
>data to it if this is a server running on your computer, of course.

Unless, of course, your users are paying for this service.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From aahz at pythoncraft.com  Wed Jul 22 23:54:11 2009
From: aahz at pythoncraft.com (Aahz)
Date: 22 Jul 2009 20:54:11 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<mailman.3433.1248109750.8015.python-list@python.org>
	<h4312f$307$1@panix3.panix.com>
	<mailman.3451.1248139114.8015.python-list@python.org>
Message-ID: <h48mt3$9f5$1@panix3.panix.com>

In article <mailman.3451.1248139114.8015.python-list at python.org>,
D'Arcy J.M. Cain <darcy at druid.net> wrote:
>On 20 Jul 2009 17:10:55 -0700
>aahz at pythoncraft.com (Aahz) wrote:
>>>I understand what you want but I can't see how a toolkit can do that.
>>>How do you program "graceful?"  It seems pretty application specific.
>> 
>> Presumably the JS toolkit generates both code and HTML.  Actions that
>> normally get executed by JS should degrade to plain HTML links and form
>> submits (or possibly not display at all if it's a pure convenience).
>
>As I said, I do understand what you are after but I still think it is a
>judgement call.  What defines "convenience?"  How does the library know
>what is essential and what is pretty?

Presumably a JS toolkit designed for this purpose would have an API to
specify the handling of such issues.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From aahz at pythoncraft.com  Wed Jul 22 23:55:20 2009
From: aahz at pythoncraft.com (Aahz)
Date: 22 Jul 2009 20:55:20 -0700
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application 
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org>
	<h424b1$gj1$1@panix3.panix.com>
	<1c994086-8c58-488f-b3b3-6161c4b2ba05@k30g2000yqf.googlegroups.com>
Message-ID: <h48mv8$39n$1@panix3.panix.com>

In article <1c994086-8c58-488f-b3b3-6161c4b2ba05 at k30g2000yqf.googlegroups.com>,
Paul Boddie  <paul at boddie.org.uk> wrote:
>On 20 Jul, 18:00, a... at pythoncraft.com (Aahz) wrote:
>>
>> Out of curiosity, are there any JavaScript toolkits that generate code
>> that degrades gracefully when JavaScript is disabled?
>
>You mean "Web toolkits which use JavaScript", I presume. I have
>written (and use myself) a toolkit/framework called XSLForms (part of
>the XSLTools distribution) which supports in-page updates (AJAX,
>effectively) that degrade to vanilla whole-page requests if JavaScript
>is switched off:
>
>http://www.boddie.org.uk/python/XSLTools.html

Thanks!  I'll take a look after OSCON.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"The volume of a pizza of thickness 'a' and radius 'z' is
given by pi*z*z*a"


From gagsl-py2 at yahoo.com.ar  Thu Jul 23 00:27:12 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 23 Jul 2009 01:27:12 -0300
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <op.uxh3ollxx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 11:36:51 -0300, Inky 788 <inky788 at gmail.com> escribi?:
> On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
> wrote:

>> The good reason is the immutability, which lets you use
>> a tuple as a dict key. ?
>
> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

Many people posted useful examples of tuples as dictionary keys in this
thread. Just to add another one (emulate SQL GROUP BY):

ope_by_dept = defaultdict(int)
total_times = defaultdict(float)

for dept_name, ope_name, ope_date, engineer in list_of_operations:
     ope_by_dept[dept_name, ope_start.month] += 1
     total_times[dept_name, engineer] += ope_end - ope_start

print "Operations per department per month"
for dept_name, month in sorted(ope_by_dept):
      print dept_name, month, ope_by_dept[dept_name, month]

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Thu Jul 23 00:27:15 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 23 Jul 2009 01:27:15 -0300
Subject: logging outgoing HTTP POST message and incoming response message
References: <d3fa609c-4621-4c18-b84b-9c115b000f27@g1g2000pra.googlegroups.com>
	<7cpcjaF2915u5U1@mid.uni-berlin.de>
	<0b403bd0-759f-49b6-9eac-3d585d877fe3@k13g2000prh.googlegroups.com>
Message-ID: <op.uxh6hxfbx6zn5v@lepton.softlabbsas.com.ar>

En Wed, 22 Jul 2009 18:18:37 -0300, scriptlearner at gmail.com
<scriptlearner at gmail.com> escribi?:
> On Jul 22, 1:54?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> You can use proxy-tools such as tcpmon or sniff traffic using wireshark.
>
> Thanks,
> but I am trying to enable some debug mode to log all outgoing and
> incoming messages for certain period of time, and running another
> proxy-tool is not very ideal.  It would be great to log it in some log
> file.

You may install a custom HTTPHandler:

class LoggingHTTPConnection(httplib.HTTPConnection):

      def request(self, method, url, body=None, headers={}):
          print method, url, headers
          httplib.HTTPConnection.request(self, method, url, body, headers)

      def getresponse(self):
          response = httplib.HTTPConnection.getresponse(self)
          print response.status, response.msg
          return response

class LoggingHTTPHandler(urllib2.HTTPHandler):
      def http_open(self, req):
          return self.do_open(LoggingHTTPConnection, req)

opener = urllib2.build_opener(LoggingHTTPHandler, ...)

-- 
Gabriel Genellina



From nagle at animats.com  Thu Jul 23 00:40:38 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 22 Jul 2009 21:40:38 -0700
Subject: MySQLdb for Python 3.1 getting close?
Message-ID: <4a67e912$0$1603$742ec2ed@news.sonic.net>

   Is MySQLdb available for Python 3.1 yet?

   http://sourceforge.net/projects/mysql-python/

says the last supported Python version is 2.5.  Any progress in sight?

				John Nagle	


From martin.hellwig at dcuktec.org  Thu Jul 23 02:16:22 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 23 Jul 2009 07:16:22 +0100
Subject: Ideas for problem with chat server application!
In-Reply-To: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
References: <02ec3d2a-fcbd-49f6-8fae-32725cc4c0cc@k6g2000yqn.googlegroups.com>
Message-ID: <LNqdnZxuvdmlnfXXnZ2dnUVZ8vqdnZ2d@bt.com>

David Adamo Jr. wrote:
<cut>
> My
> attempt was to create a windows service that start automatically and
> runs this batch file using a Network Service account on the server
> system. Although, I'm having a hard time with this (temporarily), I
> would love to ask if there are any alternatives to using a windows
> service. Suggestions are highly appreciated.

This is definitely the right way to go, perhaps reviewing a template 
which I use for windows services may help you:
http://blog.dcuktec.com/2009/07/python-windows-service-template.html

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From jayshree06comp at gmail.com  Thu Jul 23 02:37:17 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Wed, 22 Jul 2009 23:37:17 -0700 (PDT)
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
Message-ID: <b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>

On Jul 21, 8:59?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> jayshree <jayshree06c... at gmail.com> (j) wrote:
> >j> M2Crypto package not showing the 'recipient_public_key.pem' file at
> >j> linux terminal .how do i get/connect with recipient public key.
> >j> exactly i need to check how can i open this file through linux
> >j> commands.
> >j> import M2Crypto def encrypt(): recip = M2Crypto.RSA.load_pub_key(open
> >j> ('recipient_public_key.pem','rb').read()) print recip; plaintext =
> >j> whatever i need to encrypt msg = recip.public_encrypt
> >j> (plaintext,RSA.pkcs1_padding) print msg;
> >j> after calling the function its not giving any output and even any
> >j> error
> >j> i also tried as 'Will' said
> >j> pk = open('public_key.pem','rb').read() print pk; rsa =
> >j> M2Crypto.RSA.load_pub_key(pk)
> >j> whats the mistake i am not getting .will somebody help me out.
> >j> is something wrong in opening 'recipient_public_key.pem'. is M2Crypto
> >j> contain this file inbuilt .from where this file taking public key of
> >j> the recipient i'. what this file contain and how it will work .should
> >j> i need to create such a file for my purpose.if it is then how can i
> >j> create this ?and how it will retrieve the key,where i recognize my
> >j> recipient to get his public key .is something like database at server.
> >j> please give me a quick response......
> >j> looking for your answer.
>
> Please:
> 1. Type your python code with newlines and proper indentation.
> 2. Show the error messages that your code gives when you run it.
> 3. Use proper capital letters at the beginning of your sentences.
> 4. Don't fire so many questions in rapid succession.
>
> The recipient_public_key.pem file is the public key of the recipient
> which means the person that is going to receive the encrypted message.
> You should get it from the recipient him/herself or from some key store
> where s/he has deposited it.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org- Hide quoted text -
>
> - Show quoted text -
Here is the code that i used

import M2Crypto
from M2Crypto import RSA

def encrypt():
    recip = M2Crypto.RSA.load_pub_key(open
('recipient_public_key.pem','rb').read())
    #recip = M2Crypto.RSA.load_pub_key('recipient_public_key.pem')
    print recip;
    plaintext =" whatever i need to encrypt"
    msg = recip.public_encrypt(plaintext,RSA.pkcs1_padding)
    print msg;


    encrypt()


error coming like - IOError: [Errno 2] No such file or directory:
'recipient_public_key.pem'

Is this not the inbuilt file.
How should i create such type of file.


From wilk at flibuste.net  Thu Jul 23 02:44:56 2009
From: wilk at flibuste.net (William Dode)
Date: 23 Jul 2009 06:44:56 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
	<861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
	<mailman.3563.1248312318.8015.python-list@python.org>
Message-ID: <4a6806e8$0$22900$426a74cc@news.free.fr>

On 23-07-2009, Kurt Smith wrote:
> On Wed, Jul 22, 2009 at 2:48 AM, Bearophile<bearophileHUGS at lycos.com> wrote:
>> greg:
>>> Posting benchmark times for Pyrex or Cython is pretty
>>> meaningless without showing the exact code that was
>>> used, since times can vary enormously depending on
>>> how much you C-ify things.
>>
>> Was this link, shown by William, not enough?
>> http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1
>
> I took a stab at converting the recent psyco-optimized code to cython,
> and got a speedup.

thanks, i updated my repo with litle more tips.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From amrita at iisermohali.ac.in  Thu Jul 23 03:22:15 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Thu, 23 Jul 2009 12:52:15 +0530 (IST)
Subject: how two join and arrange two files together
Message-ID: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>


Hi,

I have two large files:

FileA
15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C =
21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35
23 ALA H = 8.78	N =  CA =  HA = C = 179.93.................

and

FileB
21 ALA  helix (helix_alpha, helix2)
23 ALA  helix (helix_alpha, helix3)
38 ALA  helix (helix_alpha, helix3)...........

now what i want that i will make another file in which i will join the two
file in such a way that only matching entries will come like here 21 and
23 ALA is in both files, so the output will be something like:-

21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA  helix
(helix_alpha, helix2)
23 ALA H = 8.78	N =  CA =  HA = C = 179.93|23 ALA  helix (helix_alpha,
helix3)

and further i will make another file in which i will be able to put those
lines form this file based on the missing atom value, like for 21 ALA HA
is not defined so i will put it another file based on its HA missing value
similarly i will put 23 ALA on another file based on its missing N,CA and
HA value.

I tried to join the two file based on their matching entries by:---
>>>from collections import defaultdict
>>>
>>> if __name__ == "__main__":
...      a = open("/home/amrita/alachems/chem100.txt")
...      c = open("/home/amrita/secstr/secstr100.txt")
...
>>> def source(stream):
...     return (line.strip() for line in stream)
...
...
>>> def merge(sources):
...     for m in merge([source(a),source(c)]):
...         print "|".join(c.ljust(10) for c in m)
...

but it is not giving any value.






Thanks,
Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From hendrik at microcorp.co.za  Thu Jul 23 03:25:22 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Thu, 23 Jul 2009 09:25:22 +0200
Subject: binary literal
In-Reply-To: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
Message-ID: <200907230925.22747.hendrik@microcorp.co.za>

On Wednesday 22 July 2009 12:03:44 superpollo wrote:

> can i do something like the above, but using a *binary* number? (e.g.
> 00101101 instead of 45) ?

00101101 is not hex 45.
hex 45 is 01000101

>>> chr(int('01000101',2))
'E'
>>>

- Hendrik





From hendrik at microcorp.co.za  Thu Jul 23 03:42:27 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Thu, 23 Jul 2009 09:42:27 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <200907230942.27558.hendrik@microcorp.co.za>

On Wednesday 22 July 2009 16:36:51 Inky 788 wrote:
> On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
>
> wrote:

> > The good reason is the immutability, which lets you use
> > a tuple as a dict key. ?
>
> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

Steven showed why you cannot have a mutable thing
as a key in a dict.

if you think it is contrived, then please consider how you would 
keep track of say the colour of a pixel on a screen at position
(x,y) - this is about the simplest "natural" tuple format and
example.

There are other equally valid examples, as has been pointed
out.  (may have been in another thread - am a bit confused
about that right now)

- Hendrik


From clp2 at rebertia.com  Thu Jul 23 04:16:04 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 23 Jul 2009 01:16:04 -0700
Subject: how two join and arrange two files together
In-Reply-To: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
References: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
Message-ID: <50697b2c0907230116m67a73918gbd344b9a5289b45@mail.gmail.com>

On Thu, Jul 23, 2009 at 12:22 AM, <amrita at iisermohali.ac.in> wrote:
>
> Hi,
>
> I have two large files:
>
> FileA
> 15 ALA H = 8.05 N = 119.31 CA = 52.18 HA = 4.52 C =
> 21 ALA H = 7.66 N = 123.58 CA = 54.33 HA = C = 179.35
> 23 ALA H = 8.78 N = ?CA = ?HA = C = 179.93.................
>
> and
>
> FileB
> 21 ALA ?helix (helix_alpha, helix2)
> 23 ALA ?helix (helix_alpha, helix3)
> 38 ALA ?helix (helix_alpha, helix3)...........
>
> now what i want that i will make another file in which i will join the two
> file in such a way that only matching entries will come like here 21 and
> 23 ALA is in both files, so the output will be something like:-
>
> 21 ALA H = 7.66 N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA ?helix
> (helix_alpha, helix2)
> 23 ALA H = 8.78 N = ?CA = ?HA = C = 179.93|23 ALA ?helix (helix_alpha,
> helix3)
>
> and further i will make another file in which i will be able to put those
> lines form this file based on the missing atom value, like for 21 ALA HA
> is not defined so i will put it another file based on its HA missing value
> similarly i will put 23 ALA on another file based on its missing N,CA and
> HA value.
>
> I tried to join the two file based on their matching entries by:---
>>>>from collections import defaultdict
>>>>
>>>> if __name__ == "__main__":
> ... ? ? ?a = open("/home/amrita/alachems/chem100.txt")
> ... ? ? ?c = open("/home/amrita/secstr/secstr100.txt")
> ...
>>>> def source(stream):
> ... ? ? return (line.strip() for line in stream)
> ...
> ...
>>>> def merge(sources):
> ... ? ? for m in merge([source(a),source(c)]):
> ... ? ? ? ? print "|".join(c.ljust(10) for c in m)
> ...
>
> but it is not giving any value.

You never actually called any of your <expletive deleted> functions.

Slightly corrected version:

from collections import defaultdict

def source(stream):
    return (line.strip() for line in stream)

def merge(sources):
    for m in sources:
        print "|".join(c.ljust(10) for c in m)

if __name__ == "__main__":
    a = open("/home/amrita/alachems/chem100.txt")
    c = open("/home/amrita/secstr/secstr100.txt")
    merge([source(a), source(c)])


It's still not sophisticated enough to give the exact output you're
looking for, but it is a step in the right direction.

You really should try asking someone from your CS Dept to help you. It
would seriously take a couple hours, at most.

- Chris
-- 
Still brandishing a cluestick a vain...
http://blog.rebertia.com


From pavlovevidence at gmail.com  Thu Jul 23 04:47:03 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 01:47:03 -0700 (PDT)
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org> 
	<f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com> 
	<h48lvm$qau$1@panix3.panix.com>
Message-ID: <20efdb6a-c1a5-47dc-8546-7c4ae548e22d@g1g2000pra.googlegroups.com>

On Jul 22, 8:38?pm, a... at pythoncraft.com (Aahz) wrote:
> In article <f3d88edf-b5d3-43e4-89a3-b05ef0f55... at p28g2000vbn.googlegroups.com>,
> Carl Banks ?<pavlovevide... at gmail.com> wrote:
>
> >You have to be REALLY REALLY careful not to pass any user-supplied
> >data to it if this is a server running on your computer, of course.
>
> Unless, of course, your users are paying for this service.

Well, yes, but I assume that by the time you're deliberately letting
users pay to run their programs on your server, you will already have
deployed a full-blown, multi-tiered security strategy that includes
validation by the server process.  That was sort of beyond the scope
of the OP's question.


Carl Banks


From helvinlui at gmail.com  Thu Jul 23 04:55:51 2009
From: helvinlui at gmail.com (Helvin)
Date: Thu, 23 Jul 2009 01:55:51 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
	<mailman.2902.1247154895.8015.python-list@python.org>
	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>
Message-ID: <16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>

I believe I now have vtkpython.exe. However, my 'import vtk' statement
in my python code is not working. The error says something like "no
module named vtk".
Where do I find modules for vtk in pyqt? Do they exist?

They must, right? Because there are people using vtk in pyqt? Or do I
have to use OpenGL?

Confused...
Helvin


From jjkk73 at gmail.com  Thu Jul 23 05:01:45 2009
From: jjkk73 at gmail.com (jorma kala)
Date: Thu, 23 Jul 2009 10:01:45 +0100
Subject: How to document Python code properly for Pydoc
In-Reply-To: <h47j3k$9gj$1@ger.gmane.org>
References: <bda7ac6d0907220639m48324351s5cc8153699193e82@mail.gmail.com>
	<h47j3k$9gj$1@ger.gmane.org>
Message-ID: <bda7ac6d0907230201u11680734i622825a7be34e9af@mail.gmail.com>

Thanks very much for your help

On Wed, Jul 22, 2009 at 6:43 PM, Lie Ryan <lie.1296 at gmail.com> wrote:

>  jorma kala wrote:
> > Hi,
> > Do you know where I can find the rules for documenting Python code, so
> > that automatic document generation with Pydoc makes the most of the
> > comments inserted in the code?
> > I know about documenting class and method through triple quote just
> > under the class definition. But how do you comment a specific field or
> > variable, or how do you document function arguments so that they are
> > extracted like in javadoc?
> > Thanks very much
>
> pydoc is a simple tool, and doesn't do much. You write in freeform,
> although generally you'll do something like this:
>
> def myfunc(a, b):
>    '''
>    short description of myfunc
>
>    longer description of myfunc, if necessary, and typically includes
>    description of the arguments and the behaviors. Also includes the
>    description of the return value.
>    '''
>
>    pass
>
> pydoc doesn't recognize any special markups. If you want to get more
> from the docstring, you need other documentation generator such as
> epydoc, Doxygen, or Sphinx.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/49225759/attachment-0001.html>

From user at example.net  Thu Jul 23 05:04:24 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 11:04:24 +0200
Subject: binary literal
In-Reply-To: <mailman.3566.1248333819.8015.python-list@python.org>
References: <4a66e400$0$553$4fafbaef@reader4.news.tin.it>
	<mailman.3566.1248333819.8015.python-list@python.org>
Message-ID: <4a682799$0$28504$4fafbaef@reader2.news.tin.it>

Hendrik van Rooyen wrote:
> On Wednesday 22 July 2009 12:03:44 superpollo wrote:
> 
> 
>>can i do something like the above, but using a *binary* number? (e.g.
>>00101101 instead of 45) ?
> 
> 
> 00101101 is not hex 45.
> hex 45 is 01000101
> 

whoopsie daisie!

> 
>>>>chr(int('01000101',2))
> 
> 'E'
> 

much obliged.

bye


From ryszard.szopa at gmail.com  Thu Jul 23 05:08:39 2009
From: ryszard.szopa at gmail.com (Ryszard Szopa)
Date: Thu, 23 Jul 2009 02:08:39 -0700 (PDT)
Subject: strange error when trying to log something
Message-ID: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>

Hi,

I've recently reinstalled Python 2.6 (from DMG) on my Mac, and I am
running into very strage errors. Namely, logging seems to be badly
broken. When I open the interpreter through Django's manage.py shell
and try to use logging, I get the following error:

>>> logging.critical('ala')
------------------------------------------------------------
Traceback (most recent call last):
  File "<ipython console>", line 1, in <module>
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1416, in critical
    root.critical(*((msg,)+args), **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1074, in critical
    self._log(CRITICAL, msg, args, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1142, in _log
    record = self.makeRecord(self.name, level, fn, lno, msg, args,
exc_info, func, extra)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 1117, in makeRecord
    rv = LogRecord(name, level, fn, lno, msg, args, exc_info, func)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/logging/__init__.py", line 272, in __init__
    from multiprocessing import current_process
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/multiprocessing/__init__.py", line 64, in <module>
    from multiprocessing.util import SUBDEBUG, SUBWARNING
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/multiprocessing/util.py", line 121, in <module>
    _afterfork_registry = weakref.WeakValueDictionary()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
python2.6/weakref.py", line 51, in __init__
    UserDict.UserDict.__init__(self, *args, **kw)
TypeError: unbound method __init__() must be called with UserDict
instance as first argument (got WeakValueDictionary instance instead)

I was able to silence the error (and be able to work normally) by
making UserDict.UserDict inherit from object.

Any ideas what is causing the error? Before I updated Python
everything was fine. Am I breaking a lot of things by making
UserDict.UserDict a new style class?

Thanks in advance for any insight.

  -- Ryszard Szopa


From songofacandy at gmail.com  Thu Jul 23 05:24:42 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Thu, 23 Jul 2009 02:24:42 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
Message-ID: <697fa41f-9c6a-438f-9c47-9566a79bdf82@p36g2000prn.googlegroups.com>

> What is file.encoding convention?
> If I want to write a unicode string to a file(-like) that have
> encoding attribute, I should do
> (1) try: file.write(unicode_str),
> (2) except UnicodeEncodeError: file.write(unicode_str.encode
> (file.encoding))
> like logging?
> It seems agly.

s/agly/ugly/


From __peter__ at web.de  Thu Jul 23 05:29:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 11:29:13 +0200
Subject: strange error when trying to log something
References: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>
Message-ID: <h49ah5$hv3$02$1@news.t-online.com>

Ryszard Szopa wrote:

> Hi,
> 
> I've recently reinstalled Python 2.6 (from DMG) on my Mac, and I am
> running into very strage errors. Namely, logging seems to be badly
> broken. When I open the interpreter through Django's manage.py shell
> and try to use logging, I get the following error:
> 
>>>> logging.critical('ala')
> ------------------------------------------------------------
> Traceback (most recent call last):
>   File "<ipython console>", line 1, in <module>
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1416, in critical
>     root.critical(*((msg,)+args), **kwargs)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1074, in critical
>     self._log(CRITICAL, msg, args, **kwargs)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1142, in _log
>     record = self.makeRecord(self.name, level, fn, lno, msg, args,
> exc_info, func, extra)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 1117, in makeRecord
>     rv = LogRecord(name, level, fn, lno, msg, args, exc_info, func)
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/logging/__init__.py", line 272, in __init__
>     from multiprocessing import current_process
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/multiprocessing/__init__.py", line 64, in <module>
>     from multiprocessing.util import SUBDEBUG, SUBWARNING
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/multiprocessing/util.py", line 121, in <module>
>     _afterfork_registry = weakref.WeakValueDictionary()
>   File "/Library/Frameworks/Python.framework/Versions/2.6/lib/
> python2.6/weakref.py", line 51, in __init__
>     UserDict.UserDict.__init__(self, *args, **kw)
> TypeError: unbound method __init__() must be called with UserDict
> instance as first argument (got WeakValueDictionary instance instead)
> 
> I was able to silence the error (and be able to work normally) by
> making UserDict.UserDict inherit from object.
> 
> Any ideas what is causing the error? Before I updated Python
> everything was fine. Am I breaking a lot of things by making
> UserDict.UserDict a new style class?
> 
> Thanks in advance for any insight.
> 
>   -- Ryszard Szopa

I have a hunch that you are triggering a reload() somewhere. Example:

Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import weakref
>>> weakref.WeakValueDictionary()
<WeakValueDictionary at 140598938447312>
>>> import UserDict
>>> reload(UserDict)
<module 'UserDict' from '/usr/lib/python2.6/UserDict.pyc'>
>>> weakref.WeakValueDictionary()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/weakref.py", line 51, in __init__
    UserDict.UserDict.__init__(self, *args, **kw)
TypeError: unbound method __init__() must be called with UserDict instance 
as first argument (got WeakValueDictionary instance instead)

Try restarting the interpreter after any change to source files.

Peter



From nobody at nowhere.com  Thu Jul 23 05:37:55 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 23 Jul 2009 10:37:55 +0100
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>
Message-ID: <pan.2009.07.23.09.37.54.891000@nowhere.com>

On Wed, 22 Jul 2009 15:17:52 -0700, Carl Banks wrote:

> So do all these OSes have some kind of __mega_unifying_poll system
> call that works for anything that might possibly block, that you can
> exploit from a user process?

Threads ;)

They also have the advantage that one thread can run while another is
waiting on disk I/O, which isn't something which can be done with a
select/poll interface (even if select/poll worked for files, it doesn't
help for mapped files).




From hackingkk at gmail.com  Thu Jul 23 05:50:10 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Thu, 23 Jul 2009 15:20:10 +0530
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <m2bpncl5w7.fsf@cs.uu.nl>
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl>
Message-ID: <1248342610.3698.7.camel@krishna-laptop>

On Thu, 2009-07-23 at 00:17 +0200, Piet van Oostrum wrote:
> Being a sudoer is not a privilege to issue the os.setuid system call. It
> is only a permission to use the sudo command.
> 
Yes, So I would like to know if python can change the user to some other
non-privileged user during the script execution?

> >K> I tryed using subprocess but that did not help me either.  I tryed sudo
> >K> su into the Popen command but it throws me into the terminal (shell)
> >K> with postgres as the user.
> 
> You could execute the command:
> sudo -u postgres required_command
> with subprocess.
> 
Ok, but the problem is much more complex.
What if I want to do the following.
1, change the user for a particular script to the postgres user.
2. now execute the python code for connecting to the postgresql
database.
In the second point I actually want to execute python code not shell
level command so will the sudo -u in the subprocess.Popen change the
user in the script?
In short I would just like to have the script run under another user
let's say postgres as long as a certain action is going on, for example
connecting to the postgresql database.

 
> You have another problem then: your password must be supplied unless the
> NOPASSWD flag is set in the sudoers file.
> 
That is clear, the only problem is that I want the script to run as
postgres user although it was started by the user kk.


happy hacking.
Krishnakant.




From news123 at free.fr  Thu Jul 23 05:56:45 2009
From: news123 at free.fr (News123)
Date: Thu, 23 Jul 2009 11:56:45 +0200
Subject: available formats and params for Image.save()
Message-ID: <4a6833dd$0$22599$426a34cc@news.free.fr>

Hi,

Somehow I have difficulties reading the documentation for PIL (Image)

Is there an easy way to know which formats are supported and what their
names are?

Is there an easy way to know which parameters are supported by
Image.save(). How can I list them where are they documented?


Somehow I consider the documentation to be a little weak on this points.
all the documentation says (at least where I looked) is:

>     class Image
>      |  Methods defined here:
> . . .
>  save(self, fp, format=None, **params)
>      |      Save image to file or stream

In order to find out how the format name for a .jpg file I did following:

import Image
img = Image.open("afile.jpg")
print img.format


Then I saw, that the result was 'JPEG' and not 'JPG' as I tried first

I'm at a complete loss at finding out what parameters the save function
accepts for saving a JPG file or a PNG file

Is there an easy way of finding this in any doc or do I have to dive
into the sources.


If there's no easy way:
Wouldn't a better documentation increase the 'user experience'?



Thanks in advance for any pointers


N





From nobody at nowhere.com  Thu Jul 23 06:03:58 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 23 Jul 2009 11:03:58 +0100
Subject: Multiple versions of python
References: <0b1dafb3-6725-4418-9d4e-4c55d8c213e3@c29g2000yqd.googlegroups.com>
	<mailman.3465.1248186000.8015.python-list@python.org>
Message-ID: <pan.2009.07.23.10.03.58.172000@nowhere.com>

On Tue, 21 Jul 2009 10:19:42 -0400, Dave Angel wrote:

> The other thing you may want to do in a batch file is to change the file 
> associations so that you can run the .py file directly, without typing 
> "python" or "pythonw" in front of it.
> 
> The relevant Windows commands are:     assoc and ftype

However: assoc and ftype modify the registry keys under
HKLM\Software\Classes. This works fine if these are the only relevant
keys, but if you also have settings under HKCU\Software\Classes, those
will take precedence, so assoc and/or ftype won't have any effect.

Also, you typically need at least "Power User" status in order to modify
the keys under HKLM, while any user should be able to modify those under
HKCU (HKCU is a "virtual" key, corresponding to HKU\<interactive user>).



From user at example.net  Thu Jul 23 06:23:13 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 12:23:13 +0200
Subject: raster (PIL)
Message-ID: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>

hi.

i wrote a program which transforms a string of zeroes ando ones into a 
png file.

#!/usr/bin/env python
import Image
import sys
bits_in_a_byte = 8
raster_string = """\
00000000000000000000000000000000
00100100111100100000100000111100
00100100100000100000100000100100
00111100111000100000100000100100
00100100100000100000100000100100
00100100111100111100111100111100
00000000000000000000000000000000
00000000000000000000000000000000
00000000111100100000111100000000
00000000100000100000100100000000
00000000100000100000111100000000
00000000100000100000100000000000
00000000111100111100100000000000
00000000000000000000000000000000
"""
raster_lines = raster_string.splitlines()
high = len(raster_lines)
wide = len(raster_lines[0])
bytes_in_a_row = wide/bits_in_a_byte
bitmap = ""
for raster_line in raster_lines:
     for byte_count in range(bytes_in_a_row):
         first_bit = byte_count*bits_in_a_byte
         bitmap += 
chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] , 2))
im = Image.fromstring("1", (wide , high) , bitmap)
im.save(sys.stdout , "PNG")

any suggestions for improvement?

bye


From digitig at gmail.com  Thu Jul 23 06:28:22 2009
From: digitig at gmail.com (Tim Rowe)
Date: Thu, 23 Jul 2009 11:28:22 +0100
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
Message-ID: <aee48b3c0907230328tcd8ed72r4788da787ec0df2c@mail.gmail.com>

2009/7/22 Inky 788 <inky788 at gmail.com>:

> Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> just not sophisticated enough, but I've never wanted to use a list/
> tuple as a dict key. This sounds like obscure usage, and a bit
> contrived as a reason for having *both* lists and tuples.

If you are used to working in a language that doesn't allow it then
you'll probably carry on using the work-arounds that you have always
used. It almost certainly only seems obscure because you're not
considering it when it would be a natural solution. In a language that
builds *very* heavily on the concept of dictionaries it's not obscure
at all!

-- 
Tim Rowe


From nick at craig-wood.com  Thu Jul 23 07:30:08 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 06:30:08 -0500
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<slrnh6bahs.45r.nick@irishsea.home.craig-wood.com>
	<d6f06288-4250-4065-bdf1-a880de3b875a@y7g2000yqa.googlegroups.com>
Message-ID: <slrnh6ggph.6oq.nick@irishsea.home.craig-wood.com>

srepmub <mark.dufour at gmail.com> wrote:
>  please send any program that doesn't work with shedskin (it still is
>  experimental after all) to me, or create an issue at
>  shedskin.googlecode.com, and I will have a look at the problem.

I divided and conquered the program as suggested and eventually I got
it to compile and run correctly :-)

I learnt that if you have lots of variables with indeterminate type
then shedskin takes a very long time indeed before blowing up!

I also learnt that shedskin doesn't support the idiom I'd been using
for creating shallow copies, namely the Board.__new__(Board) below.
shedskin compiles it ok, but the C++ won't compile complaning about
not being able to find __init__ methods

Producing these warnings

*WARNING* rush_hour_solver_cut_down.py:71: class 'Vehicle' has no method '__new__'
*WARNING* rush_hour_solver_cut_down.py:72: variable 'new' has no type
*WARNING* rush_hour_solver_cut_down.py:236: variable 'new_vehicle' has no type

And these compile errors

rush_hour_solver_cut_down.cpp:94: error: ?__new__? is not a member of ?__rush_hour_solver_cut_down__::Vehicle?
rush_hour_solver_cut_down.cpp:95: error: expected type-specifier before ?;? token
rush_hour_solver_cut_down.cpp: In member function ?void* __rush_hour_solver_cut_down__::Board::move(int, int)?:
rush_hour_solver_cut_down.cpp:276: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:276: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:279: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:279: error: ?void*? is not a pointer-to-object type
rush_hour_solver_cut_down.cpp:281: error: invalid conversion from ?void*? to ?__rush_hour_solver_cut_down__::Vehicle*?


    def copy(self):
        new = Board.__new__(Board)
        new.me_x = self.me_x
        new.me_y = self.me_y
        new.depth = self.depth
        new.parent = self
        new.best_child = None
        new.board = [self.board[i][:] for i in range(WIDTH)]
        new.rep = self.rep[:]
        new.vehicles = self.vehicles[:]
        return new

I changed to using copy.copy which did work, but I couldn't name my
copy methods "copy" otherwise I got this error from the C++ compile

rush_hour_solver_cut_down.cpp: In member function '__rush_hour_solver_cut_down__::Vehicle* __rush_hour_solver_cut_down__::Vehicle::copy()':
rush_hour_solver_cut_down.cpp:94: error: no matching function for call to '__rush_hour_solver_cut_down__::Vehicle::copy(__rush_hour_solver_cut_down__::Vehicle* const)'
rush_hour_solver_cut_down.cpp:89: note: candidates are: __rush_hour_solver_cut_down__::Vehicle* __rush_hour_solver_cut_down__::Vehicle::copy()
rush_hour_solver_cut_down.cpp: In member function '__rush_hour_solver_cut_down__::Board* __rush_hour_solver_cut_down__::Board::copy()':
rush_hour_solver_cut_down.cpp:135: error: no matching function for call to '__rush_hour_solver_cut_down__::Board::copy(__rush_hour_solver_cut_down__::Board* const)'
rush_hour_solver_cut_down.cpp:129: note: candidates are: __rush_hour_solver_cut_down__::Board* __rush_hour_solver_cut_down__::Board::copy()

So I renamed them to pycopy, and they ended up looking like

    def pycopy(self):
        new = copy(self)
        new.parent = self
        new.best_child = None
        new.board = [self.board[i][:] for i in range(WIDTH)]
        new.rep = self.rep[:]
        new.vehicles = self.vehicles[:]
        return new

After all that - some timing results!

Python:   9.3 seconds
Psyco:    5.8 seconds
ShedSkin: 1.0 seconds

Impressive!

I put the code http://www.craig-wood.com/nick/pub/rush_hour_solver_cut_down.py

I left in the commented out bits of code I had to change.

This is only part of the project (375 lines) - it solves Rush Hour
boards.  There is another part which I haven't attempted to compile
yet which finds the most difficult possible boards using a combination
of back tracking and a genetic algorithm.

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From stef.mientki at gmail.com  Thu Jul 23 07:36:54 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 13:36:54 +0200
Subject: sqlite3 performance problems only in python
Message-ID: <4A684B56.3020906@gmail.com>

hello,

until now I used only small / simple databases in Python with sqlite3.
Now I've a large and rather complex database.

The most simple query (with just a result of 100 rows),
takes about 70 seconds.
And all that time is consumed in "cursor.fetchall"

Using the same database in Delphi,
using the same query,
takes less than 5 seconds (including displaying the full table in a grid).

Are there in Python faster ways to get the query results ?
Would it be faster if I used an ODBC coupling and PyODBC to interface 
the database ?

thanks,
Stef Mientki


From deets at nospam.web.de  Thu Jul 23 07:47:45 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 13:47:45 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
Message-ID: <7cr0v1F28dhltU1@mid.uni-berlin.de>

superpollo wrote:

> hi.
> 
> i wrote a program which transforms a string of zeroes ando ones into a
> png file.
> 
> #!/usr/bin/env python
> import Image
> import sys
> bits_in_a_byte = 8
> raster_string = """\
> 00000000000000000000000000000000
> 00100100111100100000100000111100
> 00100100100000100000100000100100
> 00111100111000100000100000100100
> 00100100100000100000100000100100
> 00100100111100111100111100111100
> 00000000000000000000000000000000
> 00000000000000000000000000000000
> 00000000111100100000111100000000
> 00000000100000100000100100000000
> 00000000100000100000111100000000
> 00000000100000100000100000000000
> 00000000111100111100100000000000
> 00000000000000000000000000000000
> """
> raster_lines = raster_string.splitlines()
> high = len(raster_lines)
> wide = len(raster_lines[0])
> bytes_in_a_row = wide/bits_in_a_byte

This will give you the wrong result if not divideable by bits_in_a_byte. 

> bitmap = ""
> for raster_line in raster_lines:
>      for byte_count in range(bytes_in_a_row):
>          first_bit = byte_count*bits_in_a_byte
>          bitmap +=
> chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] , 2))
> im = Image.fromstring("1", (wide , high) , bitmap)
> im.save(sys.stdout , "PNG")
> 
> any suggestions for improvement?

Instead of 

res = ""
for ...:
    res += ...

use 

res = []
for ...:
    res.append(...)

"".join(res)

There are some optimizations for the +=-op on strings, but I'm not sure how
far they go, and the other form is safer.

Diez


From paul at subsignal.org  Thu Jul 23 07:50:47 2009
From: paul at subsignal.org (paul)
Date: Thu, 23 Jul 2009 13:50:47 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <1248342610.3698.7.camel@krishna-laptop>
References: <mailman.3540.1248276934.8015.python-list@python.org>	<m2bpncl5w7.fsf@cs.uu.nl>
	<1248342610.3698.7.camel@krishna-laptop>
Message-ID: <h49ine$cs8$1@ger.gmane.org>

Krishnakant schrieb:
> On Thu, 2009-07-23 at 00:17 +0200, Piet van Oostrum wrote:
>> Being a sudoer is not a privilege to issue the os.setuid system call. It
>> is only a permission to use the sudo command.
>>
> Yes, So I would like to know if python can change the user to some other
> non-privileged user during the script execution?
If the user running python program is allowed to call setuid() then yes.

> 
>>> K> I tryed using subprocess but that did not help me either.  I tryed sudo
>>> K> su into the Popen command but it throws me into the terminal (shell)
>>> K> with postgres as the user.
>> You could execute the command:
>> sudo -u postgres required_command
>> with subprocess.
>>
> Ok, but the problem is much more complex.
No.

> What if I want to do the following.
> 1, change the user for a particular script to the postgres user.
Did you try running "sudo -u postgres blabla" with subprocess?

> 2. now execute the python code for connecting to the postgresql
> database.
> In the second point I actually want to execute python code not shell
> level command so will the sudo -u in the subprocess.Popen change the
> user in the script?
No, as the name "subprocess" suggests you are spawning a new process 
which gets another uid through sudo. This does not affect the parent 
process.

hth
  Paul




From piet at cs.uu.nl  Thu Jul 23 08:06:14 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 14:06:14 +0200
Subject: Copy/paste through LAN
References: <c1e24f0f-b34f-45e8-81bd-118baa1e8632@c29g2000yqd.googlegroups.com>
Message-ID: <m2ws5zk3ih.fsf@cs.uu.nl>

>>>>> Jun <junhufr at gmail.com> (J) wrote:

>J> Hello,
>J> I've a client/server application which uses Pyro to communicate each
>J> other.
>J> Now i try to implement copy/paste through LAN between server
>J> controlled
>J> filesystem to my local windows machine (I could list files in client's
>J> window).
>J> How can i pass the url information through Pyro ?

What do you mean? Do you want to copy a file or copy file names? Copying
a file between two machines can best be done by a specialized protocol,
like HTTP or scp. Pasting a file doesn't make sense IMHO.

And URLs are just strings.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Thu Jul 23 08:23:24 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 14:23:24 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl>
	<mailman.3575.1248342706.8015.python-list@python.org>
Message-ID: <m2skgnk2pv.fsf@cs.uu.nl>

>>>>> Krishnakant <hackingkk at gmail.com> (K) wrote:

>K> On Thu, 2009-07-23 at 00:17 +0200, Piet van Oostrum wrote:
>>> Being a sudoer is not a privilege to issue the os.setuid system call. It
>>> is only a permission to use the sudo command.
>>> 
>K> Yes, So I would like to know if python can change the user to some other
>K> non-privileged user during the script execution?

As I said you can't (unless you are root). It would be a security leak if
an arbitrary user could suddenly run as another user. Sudo is the escape
mechanism but it runs commands, and is not for changing the uid in the
middle of a process.

>>> >K> I tryed using subprocess but that did not help me either.  I tryed sudo
>>> >K> su into the Popen command but it throws me into the terminal (shell)
>>> >K> with postgres as the user.
>>> 
>>> You could execute the command:
>>> sudo -u postgres required_command
>>> with subprocess.
>>> 
>K> Ok, but the problem is much more complex.
>K> What if I want to do the following.
>K> 1, change the user for a particular script to the postgres user.
>K> 2. now execute the python code for connecting to the postgresql
>K> database.
>K> In the second point I actually want to execute python code not shell
>K> level command so will the sudo -u in the subprocess.Popen change the
>K> user in the script?

You can run another python script as the other user (o even the same
python script). You said you tried subprocess. If that is acceptable
then running another python script should also be acceptable, becaus eit
is basically the same.

>K> In short I would just like to have the script run under another user
>K> let's say postgres as long as a certain action is going on, for example
>K> connecting to the postgresql database.

Why would you have to be another user for connecting to a postgres
database? The DBMS takes care of the permissions at the DB level.

Otherwise you would have to do the DB access in another script. The
script could even communicate withe the original script, e.g by pipes or
some protocol like XMLRPC.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jyoti.mickey at gmail.com  Thu Jul 23 08:30:34 2009
From: jyoti.mickey at gmail.com (Jyoti Sharma)
Date: Thu, 23 Jul 2009 18:00:34 +0530
Subject: how two join and arrange two files together
References: <mailman.3569.1248335802.8015.python-list@python.org>
Message-ID: <op.uxis08tctp94fi@jyotis>

On Thu, 23 Jul 2009 12:52:15 +0530, <amrita at iisermohali.ac.in> wrote:

>
> Hi,
>
> I have two large files:
>
> FileA
> 15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C =
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93.................
>
> and
>
> FileB
> 21 ALA  helix (helix_alpha, helix2)
> 23 ALA  helix (helix_alpha, helix3)
> 38 ALA  helix (helix_alpha, helix3)...........
>
> now what i want that i will make another file in which i will join the  
> two
> file in such a way that only matching entries will come like here 21 and
> 23 ALA is in both files, so the output will be something like:-
>
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA  helix
> (helix_alpha, helix2)
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93|23 ALA  helix (helix_alpha,
> helix3)
>
> and further i will make another file in which i will be able to put those
> lines form this file based on the missing atom value, like for 21 ALA HA
> is not defined so i will put it another file based on its HA missing  
> value
> similarly i will put 23 ALA on another file based on its missing N,CA and
> HA value.
>
> I tried to join the two file based on their matching entries by:---

(snip)

I believe there are packages available for doing such things mostly  
written in perl. But if the aim is not to develop suitable applications  
but only to obtain the desired formatted file then doing this with the  
help of something like Excel would be easiest. This is my opinion from the  
experience I have from my bioinfo programming.

Regards,
Jyoti


From hackingkk at gmail.com  Thu Jul 23 08:30:53 2009
From: hackingkk at gmail.com (Krishnakant)
Date: Thu, 23 Jul 2009 18:00:53 +0530
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <h49ine$cs8$1@ger.gmane.org>
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl> <1248342610.3698.7.camel@krishna-laptop>
	<h49ine$cs8$1@ger.gmane.org>
Message-ID: <1248352253.5100.37.camel@krishna-laptop>

On Thu, 2009-07-23 at 13:50 +0200, paul wrote:

> If the user running python program is allowed to call setuid() then yes.
> 
NO, i don't think i can do that.  I am getting opperation not permitted.

Any ways I think probably subprocess will have to sort it out.

> Did you try running "sudo -u postgres blabla" with subprocess?
> 
Yes, but still not got the intended result which is now obvious.
> > 2. now execute the python code for connecting to the postgresql
> > database.
> > In the second point I actually want to execute python code not shell
> > level command so will the sudo -u in the subprocess.Popen change the
> > user in the script?
> No, as the name "subprocess" suggests you are spawning a new process 
> which gets another uid through sudo. This does not affect the parent 
> process.
> 
Ok then here is the work-around which I am thinking to try, Plese tell
me if it is correct.
I will let that subprocess start python inthe background and execute the
connecting code to postgresql including importing the pygresql library.
Then I will create the connection and cursor objcts in that subprocess.
But my concern is, will the connection object in the child process
(subprocess) be available to the parrent process?


happy hacking.
Krishnakant.




From __peter__ at web.de  Thu Jul 23 08:35:37 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 14:35:37 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
Message-ID: <h49lek$8k0$02$1@news.t-online.com>

superpollo wrote:

> i wrote a program which transforms a string of zeroes ando ones into a
> png file.
> 
> #!/usr/bin/env python
> import Image
> import sys
> bits_in_a_byte = 8
> raster_string = """\
> 00000000000000000000000000000000
> 00100100111100100000100000111100
> 00100100100000100000100000100100
> 00111100111000100000100000100100
> 00100100100000100000100000100100
> 00100100111100111100111100111100
> 00000000000000000000000000000000
> 00000000000000000000000000000000
> 00000000111100100000111100000000
> 00000000100000100000100100000000
> 00000000100000100000111100000000
> 00000000100000100000100000000000
> 00000000111100111100100000000000
> 00000000000000000000000000000000
> """
> raster_lines = raster_string.splitlines()
> high = len(raster_lines)
> wide = len(raster_lines[0])
> bytes_in_a_row = wide/bits_in_a_byte
> bitmap = ""
> for raster_line in raster_lines:
>      for byte_count in range(bytes_in_a_row):
>          first_bit = byte_count*bits_in_a_byte
>          bitmap +=
> chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] , 2))
> im = Image.fromstring("1", (wide , high) , bitmap)
> im.save(sys.stdout , "PNG")
> 
> any suggestions for improvement?

You can simplify the inner loop:

for first_bit in range(0, wide, bits_in_a_byte):
    bitmap += ...

and get rid of a few helper variables.

Here's a different approach:

#!/usr/bin/env python
import Image
import string
import sys

mapping = string.maketrans("01", "\x00\xff")

raster_string = ...

width = raster_string.index("\n")
height = raster_string.count("\n")

raster_string = raster_string.translate(mapping, "\n")

im = Image.fromstring("L", (width, height), raster_string)
im.convert("1").save(sys.stdout, "PNG")

The idea is to move the bit-twiddling from python to code written in C, 
pointless for such a tiny picture but crucial for the performance when you 
want to manipulate larger images.

Peter



From lists at cheimes.de  Thu Jul 23 08:37:07 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 14:37:07 +0200
Subject: Looking for os.listdir() generator
Message-ID: <h49lhh$m57$1@ger.gmane.org>

Hello,

I'm looking for a generator version of os.listdir() for Python 2.5 and
newer. I know somebody has worked on it because I've seen a generator
version in a posting on some list or blog a while ago. I can't find it
anymore. It seems my Google fu is lacking today. All I can find is a
very old version of xlistdir. A Cython based solution is appreciated but
please no ctypes version.

Christian



From python.list at tim.thechases.com  Thu Jul 23 08:39:46 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 23 Jul 2009 07:39:46 -0500
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A684B56.3020906@gmail.com>
References: <4A684B56.3020906@gmail.com>
Message-ID: <4A685A12.4080800@tim.thechases.com>

> until now I used only small / simple databases in Python with sqlite3.
> Now I've a large and rather complex database.
> 
> The most simple query (with just a result of 100 rows),
> takes about 70 seconds.
> And all that time is consumed in "cursor.fetchall"
> 
> Using the same database in Delphi,
> using the same query,
> takes less than 5 seconds (including displaying the full table in a grid).

While it may seem obvious, are you doing anything time-consuming 
with those results?  Or have you tested just doing the fetchall() 
without doing any further processing?  I'm curious on the timing of

   sql = "..."
   start = time()
   cursor.execute(sql)
   rows = cursor.fetchall()
   end = time()
   print end-start

with no other processing.  I regularly write sql that's fairly 
complex and brings back somewhat large datasets (sometimes in 
sqlite), and have never experienced problems with "simple 
quer[ies] (with just a result of 100 rows" taking such 
extrordinary times

The answer from the above code will help determine whether it's 
the sqlite portion that's crazy (and might need some well-placed 
index statements; though if your Delphi code is fine, I suspect 
not), or if it's your application code that goes off into left 
field with the resulting data.

-tkc






From user at example.net  Thu Jul 23 08:41:23 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 14:41:23 +0200
Subject: raster (PIL)
In-Reply-To: <7cr0v1F28dhltU1@mid.uni-berlin.de>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<7cr0v1F28dhltU1@mid.uni-berlin.de>
Message-ID: <4a685a75$0$40009$4fafbaef@reader3.news.tin.it>

Diez B. Roggisch wrote:
> superpollo wrote:
...
>>high = len(raster_lines)
>>wide = len(raster_lines[0])
>>bytes_in_a_row = wide/bits_in_a_byte
> 
> 
> This will give you the wrong result if not divideable by bits_in_a_byte. 
> 

then maybe:

#!/usr/bin/env python
import Image
import sys
bits_in_a_byte = 8
raster_string = """\
0000000000000000000000
00100100111100100000100000111100
00100100100000100000100000100100
00111100111000100000100000100100
00100100100000100000100000100100
00100100111100111100111100111100
00000000000000000000000000000000
00000000000000000000000000000000
00000000111100100000111100000000
00000000100000100000100100000000
00000000100000100000111100000000
00000000100000100000100000000000
00000000111100111100100000000000
00000000000000000000000000000000
"""
raster_lines = raster_string.splitlines()
high = len(raster_lines)
wide = len(raster_lines[0])
bytes_in_a_row = wide/bits_in_a_byte
wide_for_real = bytes_in_a_row*bits_in_a_byte
if wide_for_real:
     bitmap = ""
     for raster_line in raster_lines:
         for byte_count in range(bytes_in_a_row):
             first_bit = byte_count*bits_in_a_byte
             bitmap += 
chr(int(raster_line[first_bit:first_bit+bits_in_a_byte] ,
2))
     im = Image.fromstring("1", (wide_for_real , high) , bitmap)
     im.save(sys.stdout , "PNG")

bye


From piet at cs.uu.nl  Thu Jul 23 08:48:29 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 14:48:29 +0200
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
	<b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>
Message-ID: <m2ocrbk1k2.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> On Jul 21, 8:59?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:

>>> The recipient_public_key.pem file is the public key of the recipient
>>> which means the person that is going to receive the encrypted message.
>>> You should get it from the recipient him/herself or from some key store
>>> where s/he has deposited it.
[...]

>j> error coming like - IOError: [Errno 2] No such file or directory:
>j> 'recipient_public_key.pem'

>j> Is this not the inbuilt file.
>j> How should i create such type of file.

You don't create it. See above. If you understand what is is you know
why it can't be builtin. If you don't understand it is better if you
first learn about OpenSSL, otherwise you run the risk to make serious
errors. 

If you are just experimenting to create a message for yourself then you
have to create the public key because you are then the recipient
yourself. That has been answered on
http://stackoverflow.com/questions/1169798/m2crypto-package 
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From stephen.cuppett at sas.com  Thu Jul 23 08:48:44 2009
From: stephen.cuppett at sas.com (Stephen Cuppett)
Date: Thu, 23 Jul 2009 08:48:44 -0400
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
Message-ID: <h49m7d$mch$1@foggy.unx.sas.com>

os.environment('QUERY_STRING')


"Fred Atkinson" <fatkinson at mishmash.com> wrote in message 
news:p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj at 4ax.com...
> Is there a pre-defined variable that returns the GET line
> (http://www.php.net/index.php?everythingafterthequestionmark) as a
> single variable (rather than individual variables)?
>
> Regards,
>
>
>
> Fred 




From stephen.cuppett at sas.com  Thu Jul 23 08:50:27 2009
From: stephen.cuppett at sas.com (Stephen Cuppett)
Date: Thu, 23 Jul 2009 08:50:27 -0400
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
Message-ID: <h49mak$mdp$1@foggy.unx.sas.com>

$_SERVER['QUERY_STRING'];

(if it's PHP)

"Fred Atkinson" <fatkinson at mishmash.com> wrote in message 
news:p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj at 4ax.com...
> Is there a pre-defined variable that returns the GET line
> (http://www.php.net/index.php?everythingafterthequestionmark) as a
> single variable (rather than individual variables)?
>
> Regards,
>
>
>
> Fred 




From user at example.net  Thu Jul 23 08:58:45 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 14:58:45 +0200
Subject: raster (PIL)
In-Reply-To: <h49lek$8k0$02$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
Message-ID: <4a685e86$0$40011$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
> superpollo wrote:
> 
> 
>>i wrote a program which transforms a string of zeroes ando ones into a
>>png file.
...
>>any suggestions for improvement?
...
> Here's a different approach:
...
> The idea is to move the bit-twiddling from python to code written in C, 
> pointless for such a tiny picture but crucial for the performance when you 
> want to manipulate larger images.

very very interesting... you know i come from a lower level language 
approach (C/Pascal) so i find it difficult (but full of fascination) to 
adapt to such a different and much simpler way of thinking.

anyways, thanks a lot.

bye



From stef.mientki at gmail.com  Thu Jul 23 09:02:45 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 15:02:45 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A685A12.4080800@tim.thechases.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
Message-ID: <4A685F75.10701@gmail.com>

Tim Chase wrote:
>> until now I used only small / simple databases in Python with sqlite3.
>> Now I've a large and rather complex database.
>>
>> The most simple query (with just a result of 100 rows),
>> takes about 70 seconds.
>> And all that time is consumed in "cursor.fetchall"
>>
>> Using the same database in Delphi,
>> using the same query,
>> takes less than 5 seconds (including displaying the full table in a 
>> grid).
>
> While it may seem obvious, are you doing anything time-consuming with 
> those results?  Or have you tested just doing the fetchall() without 
> doing any further processing?  I'm curious on the timing of
>
>   sql = "..."
>   start = time()
>   cursor.execute(sql)
>   rows = cursor.fetchall()
>   end = time()
>   print end-start
No this is exactly what I did,
I timed the execute and fetchall seperatly:
execute: 125 msec
fetchall: 71000 msec  (returning 100 rows and 25 columns)
pysqlite:  version 2.3.2

btw, I don't know if it's of any importance, the SQL-statement I perform is
select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
  from OPNAMEN
    inner join POID_VLID          on OPNAMEN.POID            = 
POID_VLID.POID
    inner join VRAAGLST           on VRAAGLST.VLID           = 
POID_VLID.VLID
    inner join VLID_SSID          on VRAAGLST.VLID           = 
VLID_SSID.VLID
    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = 
VLID_SSID.SSID
    inner join POID_SSID_SCID     on ( OPNAMEN.POID            = 
POID_SSID_SCID.POID ) and
                                     ( SUBSCHAAL_GEGEVENS.SSID = 
POID_SSID_SCID.SSID )
    inner join SCORES             on SCORES.SCID             = 
POID_SSID_SCID.SCID
    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
    and lower ( NAME_ ) = 'fatigue'
    and TEST_COUNT in (3,4)
    and DATETIME > 39814.0
    and SCORE < 30

cheers,
Stef

>
> with no other processing.  I regularly write sql that's fairly complex 
> and brings back somewhat large datasets (sometimes in sqlite), and 
> have never experienced problems with "simple quer[ies] (with just a 
> result of 100 rows" taking such extrordinary times
>
> The answer from the above code will help determine whether it's the 
> sqlite portion that's crazy (and might need some well-placed index 
> statements; though if your Delphi code is fine, I suspect not), or if 
> it's your application code that goes off into left field with the 
> resulting data.
>
> -tkc
>
>
>
>



From user at example.net  Thu Jul 23 09:02:55 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 15:02:55 +0200
Subject: raster (PIL)
In-Reply-To: <h49lek$8k0$02$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
Message-ID: <4a685f81$0$40008$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
...
> Here's a different approach:
...
> raster_string = ...
> 
> width = raster_string.index("\n")
> height = raster_string.count("\n")

your approach has a funny side-effect: try to remove just one zero from 
the first line of the raster ;-)

bye


From franke.rob at googlemail.com  Thu Jul 23 09:03:06 2009
From: franke.rob at googlemail.com (Robert Franke)
Date: Thu, 23 Jul 2009 15:03:06 +0200
Subject: Pyserial and pyQt
In-Reply-To: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
Message-ID: <d34a96990907230603o543f7dcbi467d2dda3623035@mail.gmail.com>

On Tue, Jul 21, 2009 at 9:37 PM, Seth <king.seth at gmail.com> wrote:

>
> I have used pyserial in the past but this is my first experience with
> pyQt.  I am using the Python xy package for windows current but might
> move to linux.  I have a small device that is outputting a basic text
> string.  I want to be able to read this string(from the comm port) and
> update a text box and eventually a graph in pyQt.  I can't find any
> documentation or tutorials on how to do this.  If anyone can point me
> in the right direction or give me some tips I would be grateful.
>


As I need to do something similar I looked around and found the following
recipe at activestate:

http://code.activestate.com/recipes/82965/

In the comments there is an example for PyQt.


Cheers,
Robert
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/7d2d7348/attachment-0001.html>

From user at example.net  Thu Jul 23 09:16:51 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 15:16:51 +0200
Subject: raster (PIL)
In-Reply-To: <h49lek$8k0$02$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
Message-ID: <4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
...
> im.convert("1").save(sys.stdout, "PNG")
...

a q about pil:

im.convert("1")

is different from:

im2 = im.convert("1")

right?

in the former im is changed (the method applies to im) but in the latter 
im is unchanged (first im is copied unto im2 and then the method is 
applied to im2)... am i right?

bye


From dangets at gmail.com  Thu Jul 23 09:19:33 2009
From: dangets at gmail.com (DG)
Date: Thu, 23 Jul 2009 06:19:33 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst> 
	<mailman.3560.1248307583.8015.python-list@python.org>
Message-ID: <74cd3059-cd88-418b-8444-766a125d93c3@y4g2000prf.googlegroups.com>

On Jul 22, 6:05?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James ?
> <rho... at wildebst.demon.co.uk> escribi?:
>
> > On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina ?
> > <gagsl-... at yahoo.com.ar> wrote:
>
> >> class X(object):
> >> ? ?foo = descriptor()
>
> >> x = X()
> >> x.foo = "value"
>
> > Isn't this going to create a brand new instance attribute x.foo that has ?
> > nothing to do with the descriptor anyway?
>
> No, it's up to the descriptor __set__ method what happens in this case. ?
> Think of the standard 'property' descriptor, the fset function can do ?
> whatever it wants.
> Also, a data descriptor takes precedence over any instance attribute of ?
> the same name that might exist.
>
> --
> Gabriel Genellin

You might've already thought of this (and it is annoying), but you
could pass the name through the descriptor's init method.  I believe
this is the only way besides assigning a metaclass that will look for
that type of descriptor upon class creation and set the descriptor's
name at that time.

class A(object):
    def __init__(self, attr_name):
        self._name = attr_name
    def __set__(self, instance, value):
        self.instance.__dict__[self._name] = value
        # or something like that...

class B(object):
    foo = A('foo')


From breamoreboy at yahoo.co.uk  Thu Jul 23 09:23:27 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Thu, 23 Jul 2009 14:23:27 +0100
Subject: regex: multiple matching for one string
In-Reply-To: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
Message-ID: <h49o7f$vhn$1@ger.gmane.org>

scriptlearner at gmail.com wrote:
> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
> will like to take out the values (valuea, valueb, and valuec).  How do
> I do that in Python?  The group method will only return the matched
> part.  Thanks.
> 
> p = re.compile('#a=*;b=*;c=*;')
> m = p.match(line)
>         if m:
>              print m.group(),

IMHO a regex for this is overkill, a combination of string methods such 
as split and find should suffice.

Regards.



From deets at nospam.web.de  Thu Jul 23 09:27:48 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 15:27:48 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<7cr0v1F28dhltU1@mid.uni-berlin.de>
	<4a685a75$0$40009$4fafbaef@reader3.news.tin.it>
Message-ID: <7cr6qkF28oinaU1@mid.uni-berlin.de>

superpollo wrote:

> Diez B. Roggisch wrote:
>> superpollo wrote:
> ...
>>>high = len(raster_lines)
>>>wide = len(raster_lines[0])
>>>bytes_in_a_row = wide/bits_in_a_byte
>> 
>> 
>> This will give you the wrong result if not divideable by bits_in_a_byte.
>> 
> 
> then maybe:
> 
> #!/usr/bin/env python
> import Image
> import sys
> bits_in_a_byte = 8
> raster_string = """\
> 0000000000000000000000
> 00100100111100100000100000111100
> 00100100100000100000100000100100
> 00111100111000100000100000100100
> 00100100100000100000100000100100
> 00100100111100111100111100111100
> 00000000000000000000000000000000
> 00000000000000000000000000000000
> 00000000111100100000111100000000
> 00000000100000100000100100000000
> 00000000100000100000111100000000
> 00000000100000100000100000000000
> 00000000111100111100100000000000
> 00000000000000000000000000000000
> """
> raster_lines = raster_string.splitlines()
> high = len(raster_lines)
> wide = len(raster_lines[0])
> bytes_in_a_row = wide/bits_in_a_byte
> wide_for_real = bytes_in_a_row*bits_in_a_byte

No. Because that would skip up to 7 bits.

Instead, do

bytes_in_a_row = wide/bits_in_a_byte
if wide % bits_in_a_byte:
   bytes_in_a_row += 1

Diez


From deets at nospam.web.de  Thu Jul 23 09:28:50 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 15:28:50 +0200
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
Message-ID: <7cr6siF28oinaU2@mid.uni-berlin.de>

Fred Atkinson wrote:

> Is there a pre-defined variable that returns the GET line
> (http://www.php.net/index.php?everythingafterthequestionmark) as a
> single variable (rather than individual variables)?

Variables don't return things. Functions do. And additionally the answer
depends on what and with what you actually do.

Diez


From paul at subsignal.org  Thu Jul 23 09:32:10 2009
From: paul at subsignal.org (paul)
Date: Thu, 23 Jul 2009 15:32:10 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
In-Reply-To: <1248352253.5100.37.camel@krishna-laptop>
References: <mailman.3540.1248276934.8015.python-list@python.org>	<m2bpncl5w7.fsf@cs.uu.nl>
	<1248342610.3698.7.camel@krishna-laptop>	<h49ine$cs8$1@ger.gmane.org>
	<1248352253.5100.37.camel@krishna-laptop>
Message-ID: <h49olh$1ft$1@ger.gmane.org>

Krishnakant schrieb:
> On Thu, 2009-07-23 at 13:50 +0200, paul wrote:
> 
>> If the user running python program is allowed to call setuid() then yes.
>>
> NO, i don't think i can do that.  I am getting opperation not permitted.
> 
> Any ways I think probably subprocess will have to sort it out.
> 
>> Did you try running "sudo -u postgres blabla" with subprocess?
>>
> Yes, but still not got the intended result which is now obvious.
Why is that obvious? Works for me:

---- test.py ---------
#!/usr/bin/python

from subprocess import Popen, PIPE

cmd = Popen('sudo -u vboxadd /home/pkoelle/Documents/whoami.sh', 
shell=True, stdout=PIPE, stderr=PIPE)
print "OUT: "+cmd.stdout.read()
print "ERR: "+cmd.stderr.read()

---- whoami.sh -----
#!/bin/bash
echo $UID
logger "whoami script called for $UID"

Of course, you need to adapt path and user values to your situation. The 
user you use in your 'sudo -u <user>...' call needs execute permissions 
for whoami.sh. The relevant entry in /etc/sudoers:

pkoelle ALL=NOPASSWD: /home/pkoelle/Documents/whoami.sh

hth
  Paul

PS: This has absolutely nothing to do with "connecting to postgresql". A 
"postgres user" is not a "system user" (Piet already asked the right 
questions here ;)


>>> 2. now execute the python code for connecting to the postgresql
>>> database.
>>> In the second point I actually want to execute python code not shell
>>> level command so will the sudo -u in the subprocess.Popen change the
>>> user in the script?
>> No, as the name "subprocess" suggests you are spawning a new process 
>> which gets another uid through sudo. This does not affect the parent 
>> process.
>>
> Ok then here is the work-around which I am thinking to try, Plese tell
> me if it is correct.
> I will let that subprocess start python inthe background and execute the
> connecting code to postgresql including importing the pygresql library.
> Then I will create the connection and cursor objcts in that subprocess.
> But my concern is, will the connection object in the child process
> (subprocess) be available to the parrent process?
> 
> 
> happy hacking.
> Krishnakant.
> 
> 



From fatkinson at mishmash.com  Thu Jul 23 09:41:30 2009
From: fatkinson at mishmash.com (Fred Atkinson)
Date: Thu, 23 Jul 2009 06:41:30 -0700
Subject: Predefined Variables
Message-ID: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>

	Is there a pre-defined variable that returns the GET line
(http://www.php.net/index.php?everythingafterthequestionmark) as a
single variable (rather than individual variables)?  

	Regards, 



						Fred 


From __peter__ at web.de  Thu Jul 23 09:43:36 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 15:43:36 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
	<4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <h49pe2$5nk$00$1@news.t-online.com>

superpollo wrote:

> Peter Otten wrote:
> ...
>> im.convert("1").save(sys.stdout, "PNG")
> ...
> 
> a q about pil:
> 
> im.convert("1")
> 
> is different from:
> 
> im2 = im.convert("1")
> 
> right?
> 
> in the former im is changed (the method applies to im) but in the latter
> im is unchanged (first im is copied unto im2 and then the method is
> applied to im2)... am i right?

No. A method has no clue whether its result is used or discarded. Therefore

im.convert("1")

creates a new image in the specified mode, too, which is discarded 
immediately. If you don't need the result you probably shouldn't call the 
method at all.

Peter




From user at example.net  Thu Jul 23 09:57:03 2009
From: user at example.net (superpollo)
Date: Thu, 23 Jul 2009 15:57:03 +0200
Subject: raster (PIL)
In-Reply-To: <h49pe2$5nk$00$1@news.t-online.com>
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
	<4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>
	<h49pe2$5nk$00$1@news.t-online.com>
Message-ID: <4a686c30$0$40012$4fafbaef@reader3.news.tin.it>

Peter Otten wrote:
> superpollo wrote:
> 
> 
>>Peter Otten wrote:
>>...
>>
>>>im.convert("1").save(sys.stdout, "PNG")
>>
>>...
>>
>>a q about pil:
>>
>>im.convert("1")
>>
>>is different from:
>>
>>im2 = im.convert("1")
>>
>>right?
>>
>>in the former im is changed (the method applies to im) but in the latter
>>im is unchanged (first im is copied unto im2 and then the method is
>>applied to im2)... am i right?
> 
> 
> No. A method has no clue whether its result is used or discarded. Therefore
> 
> im.convert("1")
> 
> creates a new image in the specified mode, too, which is discarded 
> immediately.

but in:

im.convert("1").save(sys.stdout, "PNG")

the new (anonymous) image created by .convert is not discarded 
*immediately*, i mean *before* the .save method is called on it, right?

bye


From paul at boddie.org.uk  Thu Jul 23 10:13:02 2009
From: paul at boddie.org.uk (Paul Boddie)
Date: Thu, 23 Jul 2009 07:13:02 -0700 (PDT)
Subject: JavaScript toolkits (was Re: ANN: Porcupine Web Application 
	Server 0.6 is released!)
References: <mailman.3416.1248070578.8015.python-announce-list@python.org> 
	<h424b1$gj1$1@panix3.panix.com>
	<1c994086-8c58-488f-b3b3-6161c4b2ba05@k30g2000yqf.googlegroups.com>
	<h48mv8$39n$1@panix3.panix.com>
Message-ID: <fcdad95c-551b-4a72-9f05-420f840e93df@h11g2000yqb.googlegroups.com>

On 23 Jul, 05:55, a... at pythoncraft.com (Aahz) wrote:
> In article <1c994086-8c58-488f-b3b3-6161c4b2b... at k30g2000yqf.googlegroups.com>,
> Paul Boddie ?<p... at boddie.org.uk> wrote:
>
> >http://www.boddie.org.uk/python/XSLTools.html
>
> Thanks! ?I'll take a look after OSCON.

The JavaScript parts of the framework are a bit complicated, I'll
admit: you have to write some nasty-looking function calls with
awkward arguments to send AJAX-style requests to the server. I've been
meaning to employ a more declarative "signals and slots" approach so
that you don't have to write in the page templates where the in-page
updates should be expected: it's really the server code that
determines this kind of thing, and so the server code should be able
to say where it wants the page to be updated.

Again, I'll try and put up some examples in the relatively near future
that will make it easier for you to see if it's your kind of thing.

Paul


From __peter__ at web.de  Thu Jul 23 10:19:38 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 16:19:38 +0200
Subject: raster (PIL)
References: <4a683a13$0$40007$4fafbaef@reader3.news.tin.it>
	<h49lek$8k0$02$1@news.t-online.com>
	<4a6862c5$0$40016$4fafbaef@reader3.news.tin.it>
	<h49pe2$5nk$00$1@news.t-online.com>
	<4a686c30$0$40012$4fafbaef@reader3.news.tin.it>
Message-ID: <h49rhk$khf$02$1@news.t-online.com>

superpollo wrote:

> Peter Otten wrote:
>> superpollo wrote:
>> 
>> 
>>>Peter Otten wrote:
>>>...
>>>
>>>>im.convert("1").save(sys.stdout, "PNG")
>>>
>>>...
>>>
>>>a q about pil:
>>>
>>>im.convert("1")
>>>
>>>is different from:
>>>
>>>im2 = im.convert("1")
>>>
>>>right?
>>>
>>>in the former im is changed (the method applies to im) but in the latter
>>>im is unchanged (first im is copied unto im2 and then the method is
>>>applied to im2)... am i right?
>> 
>> 
>> No. A method has no clue whether its result is used or discarded.
>> Therefore
>> 
>> im.convert("1")
>> 
>> creates a new image in the specified mode, too, which is discarded
>> immediately.
> 
> but in:
> 
> im.convert("1").save(sys.stdout, "PNG")
> 
> the new (anonymous) image created by .convert is not discarded
> *immediately*, i mean *before* the .save method is called on it, right?

Of course. Think of it as a shortcut for

tmp = im.convert(...)
tmp.save(...)
del tmp

Peter




From dangets at gmail.com  Thu Jul 23 10:33:55 2009
From: dangets at gmail.com (DG)
Date: Thu, 23 Jul 2009 07:33:55 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst> 
	<mailman.3560.1248307583.8015.python-list@python.org>
	<74cd3059-cd88-418b-8444-766a125d93c3@y4g2000prf.googlegroups.com>
Message-ID: <e3393507-29c0-4cb7-a62c-edd1ef6ba24d@g23g2000vbr.googlegroups.com>

On Jul 23, 7:19?am, DG <dang... at gmail.com> wrote:
> On Jul 22, 6:05?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>
>
>
> > En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James ?
> > <rho... at wildebst.demon.co.uk> escribi?:
>
> > > On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina ?
> > > <gagsl-... at yahoo.com.ar> wrote:
>
> > >> class X(object):
> > >> ? ?foo = descriptor()
>
> > >> x = X()
> > >> x.foo = "value"
>
> > > Isn't this going to create a brand new instance attribute x.foo that has ?
> > > nothing to do with the descriptor anyway?
>
> > No, it's up to the descriptor __set__ method what happens in this case. ?
> > Think of the standard 'property' descriptor, the fset function can do ?
> > whatever it wants.
> > Also, a data descriptor takes precedence over any instance attribute of ?
> > the same name that might exist.
>
> > --
> > Gabriel Genellin
>
> You might've already thought of this (and it is annoying), but you
> could pass the name through the descriptor's init method. ?I believe
> this is the only way besides assigning a metaclass that will look for
> that type of descriptor upon class creation and set the descriptor's
> name at that time.
>
> class A(object):
> ? ? def __init__(self, attr_name):
> ? ? ? ? self._name = attr_name
> ? ? def __set__(self, instance, value):
> ? ? ? ? self.instance.__dict__[self._name] = value
> ? ? ? ? # or something like that...
>
> class B(object):
> ? ? foo = A('foo')

Well of course I think of more alternatives after I post.
1) still annoying... pass the class through a 'registering' function
that will examine all of it's attrs and find the ones that are of your
descriptor type, and assign the attr_name upon that descriptor.name
attribute.

2) I just thought of, and it's kind of a hack is to do this
examination within the '__set__' method.
e.g.

class A(object):
    def __get__(self, instance, owner):
        if instance is None:
            return self
        else:
            # do something different here for instances' access
            return self

    def __set__(self, instance, value):
        cls = instance.__class__
        name = None
        for attr in dir(cls):
            if getattr(cls, attr) is self:
                name = attr
        print name


From amrita at iisermohali.ac.in  Thu Jul 23 10:34:15 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Thu, 23 Jul 2009 20:04:15 +0530 (IST)
Subject: how two join and arrange two files together
In-Reply-To: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
References: <1741.210.212.36.65.1248333735.squirrel@www.iisermohali.ac.in>
Message-ID: <20373.210.212.36.65.1248359655.squirrel@www.iisermohali.ac.in>

I tried to print those lines having C value missing by:

import re
expr = re.compile("C = None")
f = open("/home/amrita/helix.dat")
for line in f:
    if expr.search(line):
       print line

but it is not giving any value.

>
> Hi,
>
> I have two large files:
>
> FileA
> 15 ALA H = 8.05	N = 119.31 CA = 52.18 HA = 4.52	C =
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93.................
>
> and
>
> FileB
> 21 ALA  helix (helix_alpha, helix2)
> 23 ALA  helix (helix_alpha, helix3)
> 38 ALA  helix (helix_alpha, helix3)...........
>
> now what i want that i will make another file in which i will join the two
> file in such a way that only matching entries will come like here 21 and
> 23 ALA is in both files, so the output will be something like:-
>
> 21 ALA H = 7.66	N = 123.58 CA = 54.33 HA = C = 179.35| 21 ALA  helix
> (helix_alpha, helix2)
> 23 ALA H = 8.78	N =  CA =  HA = C = 179.93|23 ALA  helix (helix_alpha,
> helix3)
>
> and further i will make another file in which i will be able to put those
> lines form this file based on the missing atom value, like for 21 ALA HA
> is not defined so i will put it another file based on its HA missing value
> similarly i will put 23 ALA on another file based on its missing N,CA and
> HA value.
>
> I tried to join the two file based on their matching entries by:---
>>>>from collections import defaultdict
>>>>
>>>> if __name__ == "__main__":
> ...      a = open("/home/amrita/alachems/chem100.txt")
> ...      c = open("/home/amrita/secstr/secstr100.txt")
> ...
>>>> def source(stream):
> ...     return (line.strip() for line in stream)
> ...
> ...
>>>> def merge(sources):
> ...     for m in merge([source(a),source(c)]):
> ...         print "|".join(c.ljust(10) for c in m)
> ...
>
> but it is not giving any value.
>
>
>
>
>
>
> Thanks,
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
>


Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From rhodri at wildebst.demon.co.uk  Thu Jul 23 10:39:15 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Thu, 23 Jul 2009 15:39:15 +0100
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxhuj5olx6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst>
	<op.uxhuj5olx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <op.uxiyzpkla8ncjz@gnudebst>

On Thu, 23 Jul 2009 01:05:55 +0100, Gabriel Genellina  
<gagsl-py2 at yahoo.com.ar> wrote:

> En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James  
> <rhodri at wildebst.demon.co.uk> escribi?:
>> On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina  
>> <gagsl-py2 at yahoo.com.ar> wrote:
>>
>>
>>> class X(object):
>>>    foo = descriptor()
>>>
>>> x = X()
>>> x.foo = "value"
>>
>> Isn't this going to create a brand new instance attribute x.foo that  
>> has nothing to do with the descriptor anyway?
>
> No, it's up to the descriptor __set__ method what happens in this case.  
> Think of the standard 'property' descriptor, the fset function can do  
> whatever it wants.

If it gets called, that is.

> Also, a data descriptor takes precedence over any instance attribute of  
> the same name that might exist.

This was the bit I wasn't clear on.  Thanks!

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From manu3d at gmail.com  Thu Jul 23 10:44:50 2009
From: manu3d at gmail.com (Emanuele D'Arrigo)
Date: Thu, 23 Jul 2009 07:44:50 -0700 (PDT)
Subject: import vs imp and friends.
Message-ID: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>

Greetings,

I was looking in the archive of this newsgroup and I found this
snippet:

import imp
sourcecode = 'def foo(x): return 11*x'
mod = imp.new_module('foo')
exec sourcecode in mod.__dict__
mod.foo(16)

Together with similar and sometimes more complete snippets available
they show how a module can be created out of string, plain text files
and compiled files. Neat!

Now the question. Apart from checking sys.module first and eventually
adding the new module to it if it isn't there already, and apart from
setting __file__, is there anything else that import does and this
snippet doesn't?

Manu


From MLists at romulo.de  Thu Jul 23 10:44:56 2009
From: MLists at romulo.de (Rainer Mansfeld)
Date: Thu, 23 Jul 2009 16:44:56 +0200
Subject: Detect target name in descriptor __set__ method
In-Reply-To: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A687768.2050804@romulo.de>

Gabriel Genellina schrieb:
> I have a class attribute 'foo' which is a data descriptor. I create an 
> instance of such class. When I say instance.foo = value, the descriptor 
> __set__ method is called. Is there any way to obtain the name being 
> assigned to? ('foo' in this example). That is, I want to know the target 
> name for the assignment that triggered the __set__ method call.
> 

class descriptor(object):
     def __get__(self, instance, owner):
       return self

     def __set__(self, instance, value):
         # I want to know the *name* this value is being assigned to
         for name in instance.__class__.__dict__:
             if getattr(instance, name) is self:
                 print "assigning to %s" % name
                 break


class X(object):
     foo = descriptor()
     bar = descriptor()

class Y(object):
     foo = descriptor()
     baz = descriptor()

x = X()
y = Y()

x.foo = "value"
x.bar = "value"
y.foo = "value"
y.baz = "value"

Does this work for you?

    Rainer



From luismgz at gmail.com  Thu Jul 23 10:53:48 2009
From: luismgz at gmail.com (Neuruss)
Date: Thu, 23 Jul 2009 07:53:48 -0700 (PDT)
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org> 
	<0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com> 
	<mailman.3347.1247899831.8015.python-list@python.org>
Message-ID: <649b38ef-fced-457e-953a-ffaf2fd9012e@c29g2000yqd.googlegroups.com>

It seems psyco.org is still in the transfer process...
Is there any charitable soul with a link to a Windows binary? :-)


From lists at cheimes.de  Thu Jul 23 11:04:05 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 17:04:05 +0200
Subject: import vs imp and friends.
In-Reply-To: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
References: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
Message-ID: <h49u54$lfs$1@ger.gmane.org>

Emanuele D'Arrigo wrote:
> Now the question. Apart from checking sys.module first and eventually
> adding the new module to it if it isn't there already, and apart from
> setting __file__, is there anything else that import does and this
> snippet doesn't?

The import statement does several things. For instance it holds the
import lock to stop other threads from importing the same module again.
It also does lots of additional work for packages like relative imports,
checking __path__, setting attributes on parent packages and so on. The
import system also does a lot of work in order to find and load a
module, too.

Christian





From lists at cheimes.de  Thu Jul 23 11:17:42 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 17:17:42 +0200
Subject: ANN: psyco V2
In-Reply-To: <649b38ef-fced-457e-953a-ffaf2fd9012e@c29g2000yqd.googlegroups.com>
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<0cdc63fe-4a40-47b5-ab9c-715a8a9b0e70@d15g2000prc.googlegroups.com>
	<mailman.3347.1247899831.8015.python-list@python.org>
	<649b38ef-fced-457e-953a-ffaf2fd9012e@c29g2000yqd.googlegroups.com>
Message-ID: <4A687F16.3030501@cheimes.de>

Neuruss wrote:
> It seems psyco.org is still in the transfer process...
> Is there any charitable soul with a link to a Windows binary? :-)

It seems like Christian is already working on Windows binaries. We are
having a discussing about an obscure MinGW bug on the Python developer
list. It looks like MinGW isn't fully ABI compatible with MSVC.

Christian


From lists at cheimes.de  Thu Jul 23 11:22:55 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 17:22:55 +0200
Subject: ANN: psyco V2
In-Reply-To: <4A5FE13A.3080708__12565.7702716582$1247820318$gmane$org@stackless.com>
References: <4A5FE13A.3080708__12565.7702716582$1247820318$gmane$org@stackless.com>
Message-ID: <4A68804F.4030802@cheimes.de>

Christian Tismer wrote:
> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
> is well being considered.

Can you estimate how much work needs to be done in order to get Psyco
working on 64bit POSIX (Linux) systems?

Christian



From Aaron.Dushku at ma.usda.gov  Thu Jul 23 11:27:34 2009
From: Aaron.Dushku at ma.usda.gov (Dushku, Aaron - Amherst, MA)
Date: Thu, 23 Jul 2009 10:27:34 -0500
Subject: Office COM automatisation - calling python from VBA
Message-ID: <7B11445876E166488E821C88E5A18778032F136CA3@mostlouis7s302.agent.one.usda.gov>

I'd like a copy of that code.  Thanks for taking the time for all of us.


Sincerely,
Aaron Dushku


******************************
Aaron Dushku
GIS Specialist
USDA-NRCS
Amherst, Massachusetts
(413) 253-4379
Email:  aaron.dushku at ma.usda.gov


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/f65f6700/attachment-0001.html>

From drakonik at gmail.com  Thu Jul 23 11:29:01 2009
From: drakonik at gmail.com (Nick Dumas)
Date: Thu, 23 Jul 2009 11:29:01 -0400
Subject: regex: multiple matching for one string
In-Reply-To: <mailman.3588.1248355389.8015.python-list@python.org>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
Message-ID: <zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Agreed. Two string.split()s, first at the semi-colon and then at the
equal sign, will yield you your value, without having to fool around
with regexes.

On 7/23/2009 9:23 AM, Mark Lawrence wrote:
> scriptlearner at gmail.com wrote:
>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>> will like to take out the values (valuea, valueb, and valuec).  How do
>> I do that in Python?  The group method will only return the matched
>> part.  Thanks.
>>
>> p = re.compile('#a=*;b=*;c=*;')
>> m = p.match(line)
>>         if m:
>>              print m.group(),
> 
> IMHO a regex for this is overkill, a combination of string methods such
> as split and find should suffice.
> 
> Regards.
> 
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAkpogb0ACgkQLMI5fndAv9jtOwCgj3+YOLfKGvAdyCMOhh4NGgfy
x5YAn1ydhUYxGlvC4Z4WlWKaa1gwviSh
=jnp1
-----END PGP SIGNATURE-----


From leerisq at gmail.com  Thu Jul 23 11:33:39 2009
From: leerisq at gmail.com (LeeRisq)
Date: Thu, 23 Jul 2009 08:33:39 -0700 (PDT)
Subject: win32clipboard operation
Message-ID: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>

Hi all,

Newbie question. I've written a script that outputs to a text file.

Now, I just want to copy the content to win32clipboard for access to
other applications. Here's the mess I've come up with so far:)

import xlrd
import win32clipboard



def program_uno():
    ofile = open(r"C:\Query\DQL.txt", "w")
    book = xlrd.open_workbook("C:\DocLoader\MCL_Drawing and Legacy
Docloader Sheet.xls")
    sh = book.sheet_by_index(0)
    e = sh.cell_value(1, 0)
    a = sh.col_values(0, start_rowx=2, end_rowx=200)
    b = r'%' + e
    c = r'%Draft%'
    y = r"some text..." %(b, c)
    w = r"some more text..."
    ofile.writelines(y)
    for x in a:
        d = r'%' + x
        z = r" loop text..." %(d, c)
        f = ofile.writelines(z)
    ofile.writelines(w)


def copy_text():
    ifile = open(r"C:\Query\DQL.txt", "r")


    win32clipboard.OpenClipboard(0)
    win32clipboard.EmptyClipboard()
    win32clipboard.SetClipboardText()
    win32clipboard.CloseClipboard

program_uno()
copy_text()


From vinay_sajip at yahoo.co.uk  Thu Jul 23 11:39:50 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Thu, 23 Jul 2009 08:39:50 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
Message-ID: <716ee910-452b-4872-b4eb-5f280344c990@n11g2000yqb.googlegroups.com>

On Jul 23, 4:06 am, Naoki INADA <songofaca... at gmail.com> wrote:
> In document <http://docs.python.org/library/
> stdtypes.html#file.encoding>:
>
> >> The encoding that this file uses. When Unicode strings are written to a file,
> >>  they will be converted to byte strings using this encoding. In addition,
> >> when the file is connected to a terminal, the attribute gives the encoding
> >> that the terminal is likely to use
>
> But inlogging.StreamHandler.emit() ::
>
>                 try:
>                     if (isinstance(msg, unicode) and
>                         getattr(stream, 'encoding', None)):
>                         #fs = fs.decode(stream.encoding)
>                         try:
>                             stream.write(fs % msg)
>                         except UnicodeEncodeError:
>                             #Printing to terminals sometimes fails.
> For example,
>                             #with an encoding of 'cp1251', the above
> write will
>                             #work if written to a stream opened or
> wrapped by
>                             #the codecs module, but fail when writing
> to a
>                             #terminal even when the codepage is set to
> cp1251.
>                             #An extra encoding step seems to be
> needed.
>                             stream.write((fs % msg).encode
> (stream.encoding))
>                     else:
>                         stream.write(fs % msg)
>                 except UnicodeError:
>                     stream.write(fs % msg.encode("UTF-8"))
>
> And behavior of sys.stdout in Windows::>>> import sys
> >>> sys.stdout.encoding
> 'cp932'
> >>> u = u"???"
> >>> u
>
> u'\u3042\u3044\u3046'>>> print >>sys.stdout, u
> ???
> >>> sys.stderr.write(u)
>
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> UnicodeEncodeError: 'ascii' codec can't encode characters in position
> 0-2: ordinal not in range(128)
>
> What is file.encoding convention?
> If I want to write a unicode string to a file(-like) that have
> encoding attribute, I should do
> (1) try: file.write(unicode_str),
> (2) except UnicodeEncodeError: file.write(unicode_str.encode
> (file.encoding))
> likelogging?
> It seems agly.

If you are writing a Unicode string to a stream which has been opened
with e.g. codecs.open with a specific encoding, then the stream is
actually a wrapper. You can write Unicode strings directly to it, and
the wrapper stream will encode the Unicode to bytes using the specific
encoding and write those bytes to the underlyting stream. In your
example you didn't show sys.stderr.encoding - you showed
sys.stdout.encoding and printed out something to it which seemed to
give the correct result, but then wrote to sys.stderr which gave a
UnicodeEncodeError. What is the encoding of sys.stderr in your
example? Also note that logging had to handle what appeared to be an
oddity with terminals - they (at least sometimes) have an encoding
attribute but appear to expect to have bytes written to them, and not
Unicode. Hence the logging kludge, which should not be needed and so
has been carefully commented.

Regards,

Vinay Sajip


From Bill at SynectixLtd.com  Thu Jul 23 11:44:50 2009
From: Bill at SynectixLtd.com (Bill Davy)
Date: Thu, 23 Jul 2009 16:44:50 +0100
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
Message-ID: <7creq2F29npujU1@mid.individual.net>

"Mark Lawrence" <breamoreboy at yahoo.co.uk> wrote in message 
news:mailman.3588.1248355389.8015.python-list at python.org...
> scriptlearner at gmail.com wrote:
>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>> will like to take out the values (valuea, valueb, and valuec).  How do
>> I do that in Python?  The group method will only return the matched
>> part.  Thanks.
>>
>> p = re.compile('#a=*;b=*;c=*;')
>> m = p.match(line)
>>         if m:
>>              print m.group(),
>
> IMHO a regex for this is overkill, a combination of string methods such as 
> split and find should suffice.
>
> Regards.
>


For the OP, it can be done with regex by grouping:

p = re.compile(r'#a=(*);b=(*);c=(*);')
m = p.match(line)
       if m:
             print m.group(1),

m.group(1) has valuea in it, etc.

But this may not be the best way, but it is reasonably terse. 




From icebergwtf at gmail.com  Thu Jul 23 11:46:04 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Thu, 23 Jul 2009 23:46:04 +0800
Subject: extract c/cpp include file with regular expression
Message-ID: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>

Hi all!
I need to parse c/cpp source files, one requirement is to extract
included header file name.
here is my solution:
>>> p = re.compile(r'#\s*include\s+(?:(<)|("))(.*)(?(1)>)(?(2)")')
>>> m = re.search(p, '#include <header.h>')
>>> m.group(3)
'header.h'
>>> m = re.search(p, '#include "header.h"')
>>> m.group(3)
'header.h'
>>> m = re.search(p, '#include <header.h"')
>>> print(m)
None
>>> m = re.search(p, '#include "header.h>')
>>> print(m)
None

Pretty ugly! And I know for a valid c/cpp source file, it will be not
necessary to check and match '<' with '>' and " with ",
but I'm wondering to see more elegant way to do such thing.

tiefeng wu
2009-07-23


From victorsubervi at gmail.com  Thu Jul 23 11:46:16 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Thu, 23 Jul 2009 12:46:16 -0300
Subject: Cannot Get Form To Work
Message-ID: <4dc0cfea0907230846g4f593219t308c64eec4943f93@mail.gmail.com>

Hi:
When the form comes up the first time, there is the default value for num.
When I fill in a number in the form and press send, even though the form
sends to itself (same page name), I would think it would read the number
sent. Here again is the code:

from primeNumbers import primeNumbers

try:
 lang = form.getfirst('lang', 'en')
 browser = form.getfirst('browser', 'all')
 site = form.getfirst('site', 'bridge')
 num = form.getfirst('num','')
except:
 pass

ourFile = string.split(__file__, "/")
p = ourFile[len(ourFile) - 1]
p = p[: - 9]
site = ourFile[4][:-10]
if site != '':
 site = site[:-1]

print "Content-Type: text/html"
print
print """
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<head xmlns="http://www.w3.org/1999/xhtml">
</head>
"""
if num != '':
 num = round(float(num))
 roots = primeNumbers(num)
 print roots
if num == '':
 print """
<form action="http://13gems.com/test-Calculators_frame.py" method="post">
<input type="text" name="num" size="20" maxlength="20" value="Enter number
here..." onfocus="this.value=''" />
<input type="image" src="http://13gems.com/images/search.jpg" name="search"
id="search" />
</form>
"""
print '</body></html>\n'
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/4dde2fb9/attachment-0001.html>

From dr.mtarver at ukonline.co.uk  Thu Jul 23 11:48:46 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Thu, 23 Jul 2009 08:48:46 -0700 (PDT)
Subject: strange python scripting error
Message-ID: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>

I have a very strange error.  I have two test python files test.py and
python.py which contain the following code

#!/usr/bin/python
print "Content-type: text/html"
print
print "<html>"
print "<center>Hello, Linux.com!</center>"
print "</html>"

One file (test.py) works; you call it up and it shows a web page with

Hello, Linux.com

The other fails with a server configuration error.  Both are running
under Linux, same server, same permissions.  Running a character scan
shows that both files contain the same printable characters and are
therefore typographically identical.   They are absolutely the same.

The only hint at a difference I can see is that my ftp program says
the files are of unequal lengths.  test.py is 129 bytes long.
python.py 134 bytes long.

A zipped folder containing both files is at

www.lambdassociates.org/weird.zip

Any ideas welcome.

Mark


From icebergwtf at gmail.com  Thu Jul 23 11:54:01 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Thu, 23 Jul 2009 23:54:01 +0800
Subject: regex: multiple matching for one string
In-Reply-To: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
Message-ID: <4314c1f70907230854qcb85dc1vde5fede76b0c80ff@mail.gmail.com>

2009/7/23 scriptlearner at gmail.com <scriptlearner at gmail.com>:
> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
> will like to take out the values (valuea, valueb, and valuec). ?How do
> I do that in Python? ?The group method will only return the matched
> part. ?Thanks.
>
> p = re.compile('#a=*;b=*;c=*;')
> m = p.match(line)
> ? ? ? ?if m:
> ? ? ? ? ? ? print m.group(),
> --
> http://mail.python.org/mailman/listinfo/python-list
>

maybe like this:
>>> p = re.compile(r'#?\w+=(\w+);')
>>> l = re.findall(p, '#a=valuea;b=valueb;c=valuec;')
>>> for r in l: print(r)
...
valuea
valueb
valuec

tiefeng wu
2009-07-23


From deets at nospam.web.de  Thu Jul 23 11:57:44 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 17:57:44 +0200
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
Message-ID: <7crfjoF29e4gtU1@mid.uni-berlin.de>

Mark Tarver wrote:

> I have a very strange error.  I have two test python files test.py and
> python.py which contain the following code
> 
> #!/usr/bin/python
> print "Content-type: text/html"
> print
> print "<html>"
> print "<center>Hello, Linux.com!</center>"
> print "</html>"
> 
> One file (test.py) works; you call it up and it shows a web page with
> 
> Hello, Linux.com
> 
> The other fails with a server configuration error.  Both are running
> under Linux, same server, same permissions.  Running a character scan
> shows that both files contain the same printable characters and are
> therefore typographically identical.   They are absolutely the same.
> 
> The only hint at a difference I can see is that my ftp program says
> the files are of unequal lengths.  test.py is 129 bytes long.
> python.py 134 bytes long.
> 
> A zipped folder containing both files is at
> 
> www.lambdassociates.org/weird.zip
> 
> Any ideas welcome.

They have different line-ending-conventions. Not sure if and why that makes
a difference.

Diez


From philip at semanchuk.com  Thu Jul 23 11:58:13 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 11:58:13 -0400
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
Message-ID: <CE27720A-C736-4670-AF63-6164A859BA4F@semanchuk.com>


On Jul 23, 2009, at 11:46 AM, tiefeng wu wrote:

> Hi all!
> I need to parse c/cpp source files, one requirement is to extract
> included header file name.
> here is my solution:
>>>> p = re.compile(r'#\s*include\s+(?:(<)|("))(.*)(?(1)>)(?(2)")')
>>>> m = re.search(p, '#include <header.h>')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include "header.h"')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include <header.h"')
>>>> print(m)
> None
>>>> m = re.search(p, '#include "header.h>')
>>>> print(m)
> None
>
> Pretty ugly! And I know for a valid c/cpp source file, it will be not
> necessary to check and match '<' with '>' and " with ",
> but I'm wondering to see more elegant way to do such thing.

Hi tiefeng,
Regexes are always a little ugly IMO. =)

A side note -- does your parser need to handle /* comments like this  
one*/?  If so, then regular expressions are not going be sufficient.

Good luck
Philip



From python at mrabarnett.plus.com  Thu Jul 23 12:05:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 17:05:09 +0100
Subject: win32clipboard operation
In-Reply-To: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
Message-ID: <4A688A35.3080107@mrabarnett.plus.com>

LeeRisq wrote:
> Hi all,
> 
> Newbie question. I've written a script that outputs to a text file.
> 
> Now, I just want to copy the content to win32clipboard for access to
> other applications. Here's the mess I've come up with so far:)
> 
[snip]

def copy_text():
     ifile = open(r"C:\Query\DQL.txt", "r")
     text = ifile.read()
     ifile.close()

     win32clipboard.OpenClipboard()
     win32clipboard.EmptyClipboard()
     win32clipboard.SetClipboardText(text)
     win32clipboard.CloseClipboard()



From dstanek at dstanek.com  Thu Jul 23 12:09:55 2009
From: dstanek at dstanek.com (David Stanek)
Date: Thu, 23 Jul 2009 12:09:55 -0400
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A685F75.10701@gmail.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<4A685F75.10701@gmail.com>
Message-ID: <de32cc030907230909u35979708seb76c7193b31105@mail.gmail.com>

On Thu, Jul 23, 2009 at 9:02 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
>
> btw, I don't know if it's of any importance, the SQL-statement I perform is
> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
> ?from OPNAMEN
> ? inner join POID_VLID ? ? ? ? ?on OPNAMEN.POID ? ? ? ? ? ?= POID_VLID.POID
> ? inner join VRAAGLST ? ? ? ? ? on VRAAGLST.VLID ? ? ? ? ? = POID_VLID.VLID
> ? inner join VLID_SSID ? ? ? ? ?on VRAAGLST.VLID ? ? ? ? ? = VLID_SSID.VLID
> ? inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
> ? inner join POID_SSID_SCID ? ? on ( OPNAMEN.POID ? ? ? ? ? ?=
> POID_SSID_SCID.POID ) and
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?( SUBSCHAAL_GEGEVENS.SSID =
> POID_SSID_SCID.SSID )
> ? inner join SCORES ? ? ? ? ? ? on SCORES.SCID ? ? ? ? ? ? =
> POID_SSID_SCID.SCID
> ? inner join PID_POID ? ? ? ? ? on OPNAMEN.POID ? ? ? ? ? ?= PID_POID.POID
> ? inner join PATIENT ? ? ? ? ? ?on PATIENT.PID ? ? ? ? ? ? = PID_POID.PID
> ?where substr ( lower( NAME) , 1, 6) ?= 'cis20r'
> ? and lower ( NAME_ ) = 'fatigue'
> ? and TEST_COUNT in (3,4)
> ? and DATETIME > 39814.0
> ? and SCORE < 30

Warning: I suck at SQL and hate it with a passion...

By using lower() on the left side of the where expressions I believe
that you are table scanning. So it is not the size of the data
returned, but the size of the data that needs to be scanned.

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From R.Brodie at rl.ac.uk  Thu Jul 23 12:11:21 2009
From: R.Brodie at rl.ac.uk (Richard Brodie)
Date: Thu, 23 Jul 2009 17:11:21 +0100
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<7crfjoF29e4gtU1@mid.uni-berlin.de>
Message-ID: <h4a23a$mp4$1@south.jnrs.ja.net>


"Diez B. Roggisch" <deets at nospam.web.de> wrote in message 
news:7crfjoF29e4gtU1 at mid.uni-berlin.de...

> They have different line-ending-conventions. Not sure if and why that makes
> a difference.

Depends on your setup. Shells can be a bit dumb about it, so
it will likely break simple cgi-style hosting.

-bash: ./python.py: /usr/bin/python^M: bad interpreter: 




From python at mrabarnett.plus.com  Thu Jul 23 12:13:02 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 17:13:02 +0100
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
Message-ID: <4A688C0E.6040705@mrabarnett.plus.com>

tiefeng wu wrote:
> Hi all!
> I need to parse c/cpp source files, one requirement is to extract
> included header file name.
> here is my solution:
>>>> p = re.compile(r'#\s*include\s+(?:(<)|("))(.*)(?(1)>)(?(2)")')
>>>> m = re.search(p, '#include <header.h>')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include "header.h"')
>>>> m.group(3)
> 'header.h'
>>>> m = re.search(p, '#include <header.h"')
>>>> print(m)
> None
>>>> m = re.search(p, '#include "header.h>')
>>>> print(m)
> None
> 
> Pretty ugly! And I know for a valid c/cpp source file, it will be not
> necessary to check and match '<' with '>' and " with ",
> but I'm wondering to see more elegant way to do such thing.
> 
I'd probably do:

 >>> p = re.compile(r'#\s*include\s+(?:<([^>]*)>|"([^"]*)")')
 >>> m = p.search('#include <header.h>')
 >>> m.group(1) or m.group(2)
'header.h'


From __peter__ at web.de  Thu Jul 23 12:14:03 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 18:14:03 +0200
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<7crfjoF29e4gtU1@mid.uni-berlin.de>
Message-ID: <h4a285$nvl$00$1@news.t-online.com>

Diez B. Roggisch wrote:

> Mark Tarver wrote:
> 
>> I have a very strange error.  I have two test python files test.py and
>> python.py which contain the following code
>> 
>> #!/usr/bin/python
>> print "Content-type: text/html"
>> print
>> print "<html>"
>> print "<center>Hello, Linux.com!</center>"
>> print "</html>"
>> 
>> One file (test.py) works; you call it up and it shows a web page with
>> 
>> Hello, Linux.com
>> 
>> The other fails with a server configuration error.  Both are running
>> under Linux, same server, same permissions.  Running a character scan
>> shows that both files contain the same printable characters and are
>> therefore typographically identical.   They are absolutely the same.
>> 
>> The only hint at a difference I can see is that my ftp program says
>> the files are of unequal lengths.  test.py is 129 bytes long.
>> python.py 134 bytes long.
>> 
>> A zipped folder containing both files is at
>> 
>> www.lambdassociates.org/weird.zip
>> 
>> Any ideas welcome.
> 
> They have different line-ending-conventions. Not sure if and why that
> makes a difference.

Looks like the shell treats the CR as part of the interpreter name:

$ cat python.py
#!/usr/bin/python
print "Content-type: text/html"
print
print "<html>"
print "<center>Hello, Linux.com!</center>"
print "</html>"$
$ python python.py
Content-type: text/html

<html>
<center>Hello, Linux.com!</center>
</html>
$ chmod u+x python.py
$ ./python.py
bash: ./python.py: /usr/bin/python^M: bad interpreter: No such file or 
directory

Peter



From dangets at gmail.com  Thu Jul 23 12:21:15 2009
From: dangets at gmail.com (DG)
Date: Thu, 23 Jul 2009 09:21:15 -0700 (PDT)
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<mailman.3593.1248362137.8015.python-list@python.org>
Message-ID: <edc10982-6271-41ca-b500-99b2c48966d5@d23g2000vbm.googlegroups.com>

On Jul 23, 8:44?am, Rainer Mansfeld <MLi... at romulo.de> wrote:
> Gabriel Genellina schrieb:
>
> > I have a class attribute 'foo' which is a data descriptor. I create an
> > instance of such class. When I say instance.foo = value, the descriptor
> > __set__ method is called. Is there any way to obtain the name being
> > assigned to? ('foo' in this example). That is, I want to know the target
> > name for the assignment that triggered the __set__ method call.
>
> class descriptor(object):
> ? ? ?def __get__(self, instance, owner):
> ? ? ? ?return self
>
> ? ? ?def __set__(self, instance, value):
> ? ? ? ? ?# I want to know the *name* this value is being assigned to
> ? ? ? ? ?for name in instance.__class__.__dict__:
> ? ? ? ? ? ? ?if getattr(instance, name) is self:
> ? ? ? ? ? ? ? ? ?print "assigning to %s" % name
> ? ? ? ? ? ? ? ? ?break
>
> class X(object):
> ? ? ?foo = descriptor()
> ? ? ?bar = descriptor()
>
> class Y(object):
> ? ? ?foo = descriptor()
> ? ? ?baz = descriptor()
>
> x = X()
> y = Y()
>
> x.foo = "value"
> x.bar = "value"
> y.foo = "value"
> y.baz = "value"
>
> Does this work for you?
>
> ? ? Rainer

The reason I wasn't checking the class' '__dict__' attribute in my
solution was because this won't show any descriptors that were
inherited from base classes.  Example with some optimizations below
(sorry for the long code):

builtin_methods = dir(object)

class descriptor(object):
    def __init__(self):
        self.name = None

    def __get__(self, instance, owner):
        # if you want a 'useful' data descriptor only return self upon
        # non-instance access
        if instance is None:
            return self
        else:
            # do something besides the below for the usefulness
            return self

    def __set__(self, instance, value):
        if self.name is None:
            cls = instance.__class__
            dir_attrs = [m for m in dir(cls) if m not in
builtin_methods]
            # 'foo' is printed here
            print 'dir(cls):    ', dir_attrs
            # 'foo' is not printed here
            print 'cls.__dict__:', cls.__dict__
            for name in dir_attrs:
                if getattr(cls, name) is self:
                    self.name = name
        print "setting %s to %s" % (self.name, value)


class baseX(object):
    foo = descriptor()

class X(baseX):
    pass

x = X()
x.foo = 'bar'



From icebergwtf at gmail.com  Thu Jul 23 12:21:41 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Fri, 24 Jul 2009 00:21:41 +0800
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4A688C0E.6040705@mrabarnett.plus.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
	<4A688C0E.6040705@mrabarnett.plus.com>
Message-ID: <4314c1f70907230921j2a5eacd0n1fdac763765b922f@mail.gmail.com>

MRAB wrote:
> I'd probably do:
>
>>>> p = re.compile(r'#\s*include\s+(?:<([^>]*)>|"([^"]*)")')
>>>> m = p.search('#include <header.h>')
>>>> m.group(1) or m.group(2)
> 'header.h'
>

yes, it's easier to understand.
thanks, MRAB!
I always make things complicated :P

tiefeng wu
2009-07-23


From icebergwtf at gmail.com  Thu Jul 23 12:36:53 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Fri, 24 Jul 2009 00:36:53 +0800
Subject: extract c/cpp include file with regular expression
In-Reply-To: <35D1D3C1-ECC3-4FEC-A21E-C6A17D9E22D7@semanchuk.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
	<CE27720A-C736-4670-AF63-6164A859BA4F@semanchuk.com>
	<4314c1f70907230913t76567a7cm3b3e4649f5bc6e4e@mail.gmail.com>
	<35D1D3C1-ECC3-4FEC-A21E-C6A17D9E22D7@semanchuk.com>
Message-ID: <4314c1f70907230936w51881daaja30e1abf73742ad2@mail.gmail.com>

2009/7/24 Philip Semanchuk <philip at semanchuk.com>:
>
> I know this will sound like a sarcastic comment, but it is sincere: my
> suggestion is that if you want to parse C/C++ (or Python, or Perl, or
> Fortran, etc.), use a real parser, not regexes unless you're willing to
> sacrifice some accuracy. Sooner or later you'll come across some code that
> your regexes won't handle, like this --
>
> #ifdef FOO_BAR
> #include <this.h>
> /* #else */
> #include <that.h>
> #endif
>
>
> Parsing code is difficult...
>
I understand your point, thanks for your suggestion, Philip. And I've
met the problem like in your example
The reason I choose regex because I barely know about "real parser",
for me it still in some "dark area" :)
But I'll find something to learn.

tiefeng wu
2009-07-23


From tismer at stackless.com  Thu Jul 23 12:41:36 2009
From: tismer at stackless.com (Christian Tismer)
Date: Thu, 23 Jul 2009 09:41:36 -0700
Subject: ANN: psyco V2
In-Reply-To: <4A68804F.4030802@cheimes.de>
References: <4A5FE13A.3080708__12565.7702716582$1247820318$gmane$org@stackless.com>
	<4A68804F.4030802@cheimes.de>
Message-ID: <4A6892C0.40104@stackless.com>

On 7/23/09 8:22 AM, Christian Heimes wrote:
> Christian Tismer wrote:
>> Psyco V2 will run on X86 based 32 bit Linux, 32 bit Windows,
>> and Mac OS X. Psyco is not supporting 64 bit, yet. But it
>> is well being considered.
>
> Can you estimate how much work needs to be done in order to get Psyco
> working on 64bit POSIX (Linux) systems?

This is not easy to tell. I'm in the process of estimating
this, because my sponsor wants to know as well. They are
very interested, but it has to be somehow affordable in
time and money.

There are different paths that can be taken. Simply hacking away,
trying to go straight to 64 bit is obvious, but probably a bad
approach. Half of the system needs to be rewritten and augmented
with extra size info, and this goes very deep. I think this
way I would produce a nightmare of even more complicated code,
and would kill myself debugging-wise.

I believe I need to simplify psyco and make many parts more
abstract and more general, to become able to make it flexible.
This also means slowing the compiler down quite a lot.

Slowing it down will again become no problem, when my new
compiler strategy is ready. The number of compilations
will reduce so drastically, that the slowdown is neglectible.

Yes, I did not give an answer. I have the vague feeling of
three months full-time work. My problem right now is to
ensure that it will become less and not more :-)

cheers - chris
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From ethan at stoneleaf.us  Thu Jul 23 12:42:17 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 23 Jul 2009 09:42:17 -0700
Subject: Changing the private variables content
In-Reply-To: <4A679415.90407@stoneleaf.us>
References: <mailman.13388.1248268320.8014.python-list@python.org>	<4A671BAF.1060204@gmail.com>
	<4A679415.90407@stoneleaf.us>
Message-ID: <4A6892E9.20602@stoneleaf.us>

Or, in other words, what Steven D'Aprano had already said.  Guess I 
should read the whole thread before madly posting!  :)

~Ethan~


From mal at egenix.com  Thu Jul 23 12:56:24 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Thu, 23 Jul 2009 18:56:24 +0200
Subject: Balanced binary tree implementation
In-Reply-To: <4A662E37.6090406@gmail.com>
References: <4A662E37.6090406@gmail.com>
Message-ID: <4A689638.6050303@egenix.com>

Lucas P Melo wrote:
> Hello,
> 
> I would like to use a balanced binary tree implementation (preferably
> within some API).
> Any hints about where I could find it?
> 
> I am looking for something that implements insertion, deletion, search
> and a special search that returns the lesser element bigger than a given
> key [1].
> 
> A nice possibility would be an extensible API that allows me to inherit
> its classes and to add operations myself.
> 
> Thanks in advance.
> 
> [1] Ex: 1 2 3 4 5 6 are elements of the bbt. If I use this operation
> given 4 as the parameter, the value returned would be 5.

You might want to have a look at the btree implementation we
have in mxBeeBase:

    http://www.egenix.com/products/python/mxBase/mxBeeBase/

It's written in C and optimized for on-disk operations.

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 23 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From philip at semanchuk.com  Thu Jul 23 13:01:45 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 13:01:45 -0400
Subject: extract c/cpp include file with regular expression
In-Reply-To: <4314c1f70907230936w51881daaja30e1abf73742ad2@mail.gmail.com>
References: <4314c1f70907230846q1c038e96w87a5f8f2abac1e4d@mail.gmail.com>
	<CE27720A-C736-4670-AF63-6164A859BA4F@semanchuk.com>
	<4314c1f70907230913t76567a7cm3b3e4649f5bc6e4e@mail.gmail.com>
	<35D1D3C1-ECC3-4FEC-A21E-C6A17D9E22D7@semanchuk.com>
	<4314c1f70907230936w51881daaja30e1abf73742ad2@mail.gmail.com>
Message-ID: <6835BCF7-0B3C-4E5D-B737-57B288D786D3@semanchuk.com>


On Jul 23, 2009, at 12:36 PM, tiefeng wu wrote:

> 2009/7/24 Philip Semanchuk <philip at semanchuk.com>:
>>
>> I know this will sound like a sarcastic comment, but it is sincere:  
>> my
>> suggestion is that if you want to parse C/C++ (or Python, or Perl, or
>> Fortran, etc.), use a real parser, not regexes unless you're  
>> willing to
>> sacrifice some accuracy. Sooner or later you'll come across some  
>> code that
>> your regexes won't handle, like this --
>>
>> #ifdef FOO_BAR
>> #include <this.h>
>> /* #else */
>> #include <that.h>
>> #endif
>>
>>
>> Parsing code is difficult...
>>
> I understand your point, thanks for your suggestion, Philip. And I've
> met the problem like in your example
> The reason I choose regex because I barely know about "real parser",
> for me it still in some "dark area" :)
> But I'll find something to learn.

Yes! Learning is always good. And as I said, if you don't mind missing  
some unusual cases, regexes are fine. I don't know how accurate you  
want your results to be.

As for real parsers, there's lots of them out there, although they may  
be overkill for what you want to do. Here's one written entirely in  
Python:
http://www.dabeaz.com/ply/

Whatever you choose, good luck with it.

Cheers
Philip



From robert.kern at gmail.com  Thu Jul 23 13:03:03 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 23 Jul 2009 12:03:03 -0500
Subject: PyQt GUI
In-Reply-To: <16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
	<mailman.2864.1247095779.8015.python-list@python.org>	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>	<mailman.2902.1247154895.8015.python-list@python.org>	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>
	<16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>
Message-ID: <h4a548$eb6$1@ger.gmane.org>

On 2009-07-23 03:55, Helvin wrote:
> I believe I now have vtkpython.exe. However, my 'import vtk' statement
> in my python code is not working. The error says something like "no
> module named vtk".
> Where do I find modules for vtk in pyqt? Do they exist?

There are no VTK modules in PyQt itself. The PyQt support is in the vtk package 
which can be built with VTK itself. You will need to install VTK and the vtk 
package correctly in order to achieve this. vtkpython.exe is not going to help 
you. Ignore it. After you have built VTK, you need to do an extra step to 
install the vtk package to where your Python interpreter will be able to find it.

Let's say that your build directory is c:\vtkbuild.

   cd \vtkbuild\Wrapping\Python
   python setup.py install
   cd \

Now you should be able to import vtk from your normal Python interpreter. If you 
are still having problems, you will need to copy-and-paste exactly what you did 
and what error messages you got. Do not paraphrase error messages.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dwbear75 at gmail.com  Thu Jul 23 13:06:35 2009
From: dwbear75 at gmail.com (DwBear75)
Date: Thu, 23 Jul 2009 10:06:35 -0700 (PDT)
Subject: installing 2.6 on vista64
Message-ID: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>

I just downloaded and attempted to install python 2.6.2.  The
installer proceeds to do its work then dies, leaving an entry in the
eventlog:

Windows Installer installed the product. Product Name: Python 2.6.2.
Product Version: 2.6.2150. Product Language: 1033. Installation
success or error status: 1602.

Googling for this I wasn't able to narrow the results down to
something usable. Anyone know of issues and how to fix them installing
on vista 64 (yes, I have 8 gigs of ram)


From tismer at stackless.com  Thu Jul 23 13:06:43 2009
From: tismer at stackless.com (Christian Tismer)
Date: Thu, 23 Jul 2009 10:06:43 -0700
Subject: ANN: psyco V2
In-Reply-To: <639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
Message-ID: <4A6898A3.3060609@stackless.com>

On 7/17/09 4:11 AM, Bearophile wrote:
> Very good, thank you. I'll try it when I can.
>
> Is Psyco3 going to borrow/steal some ideas/code from Unladen Swallow?

Psyco3: nice typo! :-)

Well, I haven't so far found a new idea there that I'd want
to borrow and did not know from PyPy, before.
Wasn't the project plan saying the opposite, borrowing
some ideas from psyco? :-)
http://code.google.com/p/unladen-swallow/wiki/ProjectPlan

> The problem I have with Psyco1.6 is that you can't use the normal
> profilers to know how much seconds of running time is taken by each
> function/method of your code.

Yes, the profiler hooks are not useful with psyco. You need
to write extra functions for timing, as we do in the benchmark
directory.

> Psyco1.6 has a profile() function, but I am not much able to use it
> yet.

The profile() function is used for profile driven compilation,
as opposed to psyco.full(). This will go away, pretty soon.
Psyco will only be switched on or off.

Maybe I will add an option for profiling the compiled code.
Interesting idea!

cheers - chris

-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From leerisq at gmail.com  Thu Jul 23 13:07:05 2009
From: leerisq at gmail.com (LeeRisq)
Date: Thu, 23 Jul 2009 10:07:05 -0700 (PDT)
Subject: win32clipboard operation
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
	<mailman.3601.1248365085.8015.python-list@python.org>
Message-ID: <b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>

On Jul 23, 9:05?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> LeeRisq wrote:
> > Hi all,
>
> > Newbie question. I've written a script that outputs to a text file.
>
> > Now, I just want to copy the content to win32clipboard for access to
> > other applications. Here's the mess I've come up with so far:)
>
> [snip]
>
> def copy_text():
> ? ? ?ifile = open(r"C:\Query\DQL.txt", "r")
> ? ? ?text = ifile.read()
> ? ? ?ifile.close()
>
> ? ? ?win32clipboard.OpenClipboard()
> ? ? ?win32clipboard.EmptyClipboard()
> ? ? ?win32clipboard.SetClipboardText(text)
> ? ? ?win32clipboard.CloseClipboard()

I've actually tried this configuration, but I did it again just to be
sure. The program executes without exception, but the text still isn't
copied to the clipboard. Any ideas?


From robert.kern at gmail.com  Thu Jul 23 13:09:55 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 23 Jul 2009 12:09:55 -0500
Subject: import vs imp and friends.
In-Reply-To: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
References: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
Message-ID: <h4a5h4$eb6$3@ger.gmane.org>

On 2009-07-23 09:44, Emanuele D'Arrigo wrote:
> Greetings,
>
> I was looking in the archive of this newsgroup and I found this
> snippet:
>
> import imp
> sourcecode = 'def foo(x): return 11*x'
> mod = imp.new_module('foo')
> exec sourcecode in mod.__dict__
> mod.foo(16)
>
> Together with similar and sometimes more complete snippets available
> they show how a module can be created out of string, plain text files
> and compiled files. Neat!
>
> Now the question. Apart from checking sys.module first and eventually
> adding the new module to it if it isn't there already, and apart from
> setting __file__, is there anything else that import does and this
> snippet doesn't?

Brett Cannon has a good presentation that covers basically the entirety of the 
import mechanism:

http://us.pycon.org/2008/conference/schedule/event/12/

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From igouy2 at yahoo.com  Thu Jul 23 13:15:00 2009
From: igouy2 at yahoo.com (Isaac Gouy)
Date: Thu, 23 Jul 2009 10:15:00 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
Message-ID: <72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>

On Jul 21, 10:09?pm, Raffael Cavallaro
<raffaelcavall... at pas.espam.s.il.vous.plait.mac.com> wrote:
> On 2009-07-21 19:06:02 -0400, Neil Hodgson
> <nyamatongwe+thun... at gmail.com> said:
>
> > ? ?Python uses native threads.
>
> So it can be teh-slowness on all ur cores!
>
> <http://shootout.alioth.debian.org/u64q/benchmark.php?test=nbody?=all>
>
> The global interpreter lock doesn't help much either.


As you've linked to programs that /have not/ been written to use
threading or multiple cores (look at the "~ CPU Load" column) I get
the feeling I'm missing the joke?





From breamoreboy at yahoo.co.uk  Thu Jul 23 13:21:59 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Thu, 23 Jul 2009 18:21:59 +0100
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
Message-ID: <h4a667$hur$1@ger.gmane.org>

Phillip B Oldham wrote:
> My colleagues and I have been working with python for around 6 months
> now, and while we love a lot of what python has done for us and what
> it enables us to do some of the decisions behind such certain
> data-types and their related methods baffle us slightly (when compared
> to the decisions made in other, similarly powerful languages).
> 
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
> 

[rest of original snipped as already discussed]

Sorry if this has been discussed and I've missed it, but how about 
memory allocation.  An immutable tuple has a fixed memory allocation 
whereas that for the mutable list must be liable to change.  You might 
like to look at the recent thread on this ng 'List insertion cost' and 
follow the links to Raymond Hettinger's power point presentation.

Kindest regards.

Mark Lawrence.



From piet at cs.uu.nl  Thu Jul 23 13:25:48 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 19:25:48 +0200
Subject: challenging problem for changing to a dedicated non-privileged
	user within a script.
References: <mailman.3540.1248276934.8015.python-list@python.org>
	<m2bpncl5w7.fsf@cs.uu.nl> <1248342610.3698.7.camel@krishna-laptop>
	<h49ine$cs8$1@ger.gmane.org>
	<mailman.3583.1248352321.8015.python-list@python.org>
Message-ID: <m2d47rjopv.fsf@cs.uu.nl>

>>>>> Krishnakant <hackingkk at gmail.com> (K) wrote:

>K> On Thu, 2009-07-23 at 13:50 +0200, paul wrote:
>>> If the user running python program is allowed to call setuid() then yes.
>>> 
>K> NO, i don't think i can do that.  I am getting opperation not permitted.

>K> Any ways I think probably subprocess will have to sort it out.

>>> Did you try running "sudo -u postgres blabla" with subprocess?
>>> 
>K> Yes, but still not got the intended result which is now obvious.
>>> > 2. now execute the python code for connecting to the postgresql
>>> > database.
>>> > In the second point I actually want to execute python code not shell
>>> > level command so will the sudo -u in the subprocess.Popen change the
>>> > user in the script?
>>> No, as the name "subprocess" suggests you are spawning a new process 
>>> which gets another uid through sudo. This does not affect the parent 
>>> process.
>>> 
>K> Ok then here is the work-around which I am thinking to try, Plese tell
>K> me if it is correct.
>K> I will let that subprocess start python inthe background and execute the
>K> connecting code to postgresql including importing the pygresql library.
>K> Then I will create the connection and cursor objcts in that subprocess.
>K> But my concern is, will the connection object in the child process
>K> (subprocess) be available to the parrent process?

No. However it is still not clear why you want to run under the postgres
user id. Why can't the original process not do the postgres connection?

If that is really impossible, then you might start the new process with
sudo and let it do a socket tunnelling to postgress, i.e. make a
connection to the postgres server and a socket connection to the
original Python script, and copy everything from one socket to the other
- in both directions. However this can also be done with a ssh tunnel
which might be simpler.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From python at mrabarnett.plus.com  Thu Jul 23 13:42:21 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 18:42:21 +0100
Subject: win32clipboard operation
In-Reply-To: <b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>	<mailman.3601.1248365085.8015.python-list@python.org>
	<b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>
Message-ID: <4A68A0FD.4010204@mrabarnett.plus.com>

LeeRisq wrote:
> On Jul 23, 9:05 am, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> LeeRisq wrote:
>>> Hi all,
>>> Newbie question. I've written a script that outputs to a text file.
>>> Now, I just want to copy the content to win32clipboard for access to
>>> other applications. Here's the mess I've come up with so far:)
>> [snip]
>>
>> def copy_text():
>>      ifile = open(r"C:\Query\DQL.txt", "r")
>>      text = ifile.read()
>>      ifile.close()
>>
>>      win32clipboard.OpenClipboard()
>>      win32clipboard.EmptyClipboard()
>>      win32clipboard.SetClipboardText(text)
>>      win32clipboard.CloseClipboard()
> 
> I've actually tried this configuration, but I did it again just to be
> sure. The program executes without exception, but the text still isn't
> copied to the clipboard. Any ideas?

All I can say is that it works for me (Windows XP Pro, service pack 3).


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Thu Jul 23 13:45:52 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Thu, 23 Jul 2009 13:45:52 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
Message-ID: <h4a7kg$q36$1@news.eternal-september.org>

On 2009-07-23 13:15:00 -0400, Isaac Gouy <igouy2 at yahoo.com> said:

> I get
> the feeling I'm missing the joke?

Yes, you are missing the joke. The point is that if python is 60x 
slower than C, even if there were not a GIL, it would require running 
the python program on a 60 core machine just reach parity with C. The 
existence of the GIL means that in reality you'd probably need a 
several hundred core machine running python just to equal what C can do 
on one core. Hence the 13375p34k pseudo quote - "teh slowness on all ur 
cores!"
-- 
Raffael Cavallaro



From alex.repenning at gmail.com  Thu Jul 23 13:54:26 2009
From: alex.repenning at gmail.com (game_designer)
Date: Thu, 23 Jul 2009 10:54:26 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org> 
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
Message-ID: <c978ad4e-16ce-4a5e-a361-7a17f92be12c@12g2000pri.googlegroups.com>

Perhaps like Xah Lee I find, after many years of Lisp programming,
these discussions increasingly frustrating and even, in some sense,
amazing. We can speculate all we want about syntax and semantics of
programing languages. What counts in the end are really the PRAGMATICS
of programming languages. How can I do something with a language that
is USEFUL to me? Will the result be good looking, and snappy or some
ugly, dated looking, crashing application? For instance, last time I
played with Scheme (drScheme) to explore some OpenGL 3D issue I was
not impressed at all. One can debate the syntax and semantics of
Scheme but in that particular instance all that was important to me
was the fact that the Scheme example performed terrible and the
threading fell completely apart when running more that a single OpenGL
window. Perhaps this was coded poorly but I don't care. Scheme left a
pretty bad impression.


alex

Prof. Alexander Repenning

University of Colorado
Computer Science Department
Boulder, CO 80309-430


From piet at cs.uu.nl  Thu Jul 23 14:20:50 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 20:20:50 +0200
Subject: sqlite3 performance problems only in python
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<mailman.3586.1248354168.8015.python-list@python.org>
Message-ID: <m28wifjm65.fsf@cs.uu.nl>

>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:

>SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>SM>  from OPNAMEN
>SM>    inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>SM>    inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>SM>    inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>SM>    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>SM>    inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>SM> POID_SSID_SCID.POID ) and
>SM>                                     ( SUBSCHAAL_GEGEVENS.SSID =
>SM> POID_SSID_SCID.SSID )
>SM>    inner join SCORES             on SCORES.SCID             =
>SM> POID_SSID_SCID.SCID
>SM>    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>SM>    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>SM>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>SM>    and lower ( NAME_ ) = 'fatigue'
>SM>    and TEST_COUNT in (3,4)
>SM>    and DATETIME > 39814.0
>SM>    and SCORE < 30

1) Do you have indices on the join fields?
2) Look at the ANALYZE command
3) Look at the EXPLAIN command
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From paul-donnelly at sbcglobal.net  Thu Jul 23 15:09:31 2009
From: paul-donnelly at sbcglobal.net (Paul Donnelly)
Date: Thu, 23 Jul 2009 14:09:31 -0500
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
	<c978ad4e-16ce-4a5e-a361-7a17f92be12c@12g2000pri.googlegroups.com>
Message-ID: <87r5w72p3o.fsf@plap.localdomain>

game_designer <alex.repenning at gmail.com> writes:

> Perhaps like Xah Lee I find, after many years of Lisp programming,
> these discussions increasingly frustrating and even, in some sense,
> amazing. We can speculate all we want about syntax and semantics of
> programing languages. What counts in the end are really the PRAGMATICS
> of programming languages. How can I do something with a language that
> is USEFUL to me? Will the result be good looking, and snappy or some
> ugly, dated looking, crashing application? For instance, last time I
> played with Scheme (drScheme) to explore some OpenGL 3D issue I was
> not impressed at all. One can debate the syntax and semantics of
> Scheme but in that particular instance all that was important to me
> was the fact that the Scheme example performed terrible and the
> threading fell completely apart when running more that a single OpenGL
> window. Perhaps this was coded poorly but I don't care. Scheme left a
> pretty bad impression.

One implementation of one dialect of Lisp worked poorly for one
particular project some unspecified number of years ago, judging by code
(written by you, no less) that may or may not have been terrible? I
appreciate that this was a frustrating experience, but I don't see what
lesson about Lisp programming we're supposed to be getting from this.


From bbarbero at inescporto.pt  Thu Jul 23 15:23:54 2009
From: bbarbero at inescporto.pt (bbarbero at inescporto.pt)
Date: Thu, 23 Jul 2009 21:23:54 +0200
Subject: Problems in commands.getoutput(cmd) with sox
Message-ID: <20090723212354.5378695qs4beje8a@horde.inescporto.pt>

Hello to all!

I am a new researcher, new to Python as well, and I have a problem,  
when I try to get commands from sox in a python script. I am going  
crazy, because this code has been working before.. so I dont really  
know whats going on..

Ive already seen some solutions that match with what I have. I am  
running this:



         if os.path.splitext(file_au)[1] == ".au":
           	resampled_file_path = os.path.join(resampled_path, file_au)
            	cmd = "sox " + dir_file + " -r 44100 " + resampled_file_path
            	print cmd
		output = commands.getoutput(cmd)
		print output

What i do, is just to resample a song from dir_file to  
resampled_file_path. As a result of "cmd" I get:

....
sox /Volumes/HAL/Datasets/Audio/gtzan_genres/rock/rock.00097.au -r  
44100  
/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resampled/rock/rock.00097.au
.....

If I run this on the command line, it will work perfectly!

But The program stops at

  File  
"/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resamplingto44.py",  
line 35
     output = commands.getoutput(cmd)
     ^
IndentationError: unexpected indent

I dont have any idea, whats going on, I am trying lot of things, but I  
can understand where is the error as it has been running perfectly  
before.

Any suggestions will be more than welcome! Thanks in advance for your help!

Best regards,
Beatriz Mora.



----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.


From nick at craig-wood.com  Thu Jul 23 15:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 14:29:57 -0500
Subject: extract c/cpp include file with regular expression
References: <mailman.3597.1248363967.8015.python-list@python.org>
Message-ID: <slrnh6he16.dgi.nick@irishsea.home.craig-wood.com>

tiefeng wu <icebergwtf at gmail.com> wrote:
>  I need to parse c/cpp source files, one requirement is to extract
>  included header file name.

If you are serious about parsing C code then you'll want to
investigate gcc-xml

http://www.gccxml.org/HTML/Index.html

This runs the gcc frontend over the code but instead of producing an
object file, it produces a machine readable xml file describing the
source.

It is used by h2xml.py / xml2py.py to make ctypes header file
automatically.

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From gslindstrom at gmail.com  Thu Jul 23 15:30:09 2009
From: gslindstrom at gmail.com (Greg Lindstrom)
Date: Thu, 23 Jul 2009 14:30:09 -0500
Subject: Creating xml
Message-ID: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>

It's been a while since I've played with XML using Python but I've been
asked to create XML using data from our postgres database.  Currently we are
generating XML directly from the database using a set of stored procedures
but it is too slow (yes, I have numbers).  I have been asked to create a
routine to generate the XML to see if it will be faster that the sprocs
(which I think it will be, based on other routines we have running).  But I
digress...

Using my favorite search engine I see that there is a lot of material on
Python and XML.  At the risk of starting something (which is not my
intention), what are my options if I want to create xml?  Ceratinly writing
my own routine is an option, but I bet there are better ones :-)

How about if I need/want to parse or process an XML file?

Thanks!

--greg
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/5730595d/attachment-0001.html>

From piet at cs.uu.nl  Thu Jul 23 15:30:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 23 Jul 2009 21:30:56 +0200
Subject: Looking for os.listdir() generator
References: <mailman.3584.1248352640.8015.python-list@python.org>
Message-ID: <m24ot3jixb.fsf@cs.uu.nl>

>>>>> Christian Heimes <lists at cheimes.de> (CH) wrote:

>CH> Hello,
>CH> I'm looking for a generator version of os.listdir() for Python 2.5 and
>CH> newer. I know somebody has worked on it because I've seen a generator
>CH> version in a posting on some list or blog a while ago. I can't find it
>CH> anymore. It seems my Google fu is lacking today. All I can find is a
>CH> very old version of xlistdir. A Cython based solution is appreciated but
>CH> please no ctypes version.

Nick Craig-Wood <nick at craig-wood.com> posted these about 5 weeks ago in
the thread `waling a directory with very many files' [sic!]

Message id's: 
<slrnh3c0r8.7rv.nick at irishsea.home.craig-wood.com> (ctypes)
<slrnh3fvbp.3pv.nick at irishsea.home.craig-wood.com> (Cython)

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From leerisq at gmail.com  Thu Jul 23 15:31:14 2009
From: leerisq at gmail.com (LeeRisq)
Date: Thu, 23 Jul 2009 12:31:14 -0700 (PDT)
Subject: win32clipboard operation
References: <c2f3a5f3-6bd8-45e0-a7f2-46225493ffac@c14g2000yqm.googlegroups.com>
	<mailman.3601.1248365085.8015.python-list@python.org>
	<b008879b-3fd6-4b24-80b1-07272d051172@n11g2000yqb.googlegroups.com>
Message-ID: <b6ed7465-b9e0-42a2-8a5f-d2eeae358c03@j32g2000yqh.googlegroups.com>

> I've actually tried this configuration, but I did it again just to be
> sure. The program executes without exception, but the text still isn't
> copied to the clipboard. Any ideas?

So, I think I've figured out the issue. Which brings me to another
question...why is it that I can manually copy and paste the text
without issue, but when I run a python script that copies the same
text to the clipboard, it won't accept the amount of text I am placing
on the clipboard. Is there some kind of setting I am missing? Buffer
size maybe?



From clp2 at rebertia.com  Thu Jul 23 15:32:58 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 23 Jul 2009 12:32:58 -0700
Subject: Creating xml
In-Reply-To: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
References: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
Message-ID: <50697b2c0907231232o4e5614dame0adee88d4a15cf@mail.gmail.com>

On Thu, Jul 23, 2009 at 12:30 PM, Greg Lindstrom<gslindstrom at gmail.com> wrote:
<snip>
> How about if I need/want to parse or process an XML file?

xml.etree.ElementTree in the standard library:
http://docs.python.org/library/xml.etree.elementtree.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From vinay_sajip at yahoo.co.uk  Thu Jul 23 15:42:29 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Thu, 23 Jul 2009 12:42:29 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
Message-ID: <2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>

On Jul 23, 4:06 am, Naoki INADA <songofaca... at gmail.com> wrote:
> In document <http://docs.python.org/library/
> stdtypes.html#file.encoding>:
>
> >> The encoding that this file uses. When Unicode strings are written to a file,
> >>  they will be converted to byte strings using this encoding. In addition,
> >> when the file is connected to a terminal, the attribute gives the encoding
> >> that the terminal is likely to use
>
> But inlogging.StreamHandler.emit() ::
>
>                 try:
>                     if (isinstance(msg, unicode) and
>                         getattr(stream, 'encoding', None)):
>                         #fs = fs.decode(stream.encoding)
>                         try:
>                             stream.write(fs % msg)
>                         except UnicodeEncodeError:
>                             #Printing to terminals sometimes fails.
> For example,
>                             #with an encoding of 'cp1251', the above
> write will
>                             #work if written to a stream opened or
> wrapped by
>                             #the codecs module, but fail when writing
> to a
>                             #terminal even when the codepage is set to
> cp1251.
>                             #An extra encoding step seems to be
> needed.
>                             stream.write((fs % msg).encode
> (stream.encoding))
>                     else:
>                         stream.write(fs % msg)
>                 except UnicodeError:
>                     stream.write(fs % msg.encode("UTF-8"))
>
> And behavior of sys.stdout in Windows::>>> import sys
> >>> sys.stdout.encoding
> 'cp932'
> >>> u = u"???"
> >>> u
>
> u'\u3042\u3044\u3046'>>> print >>sys.stdout, u
> ???
> >>> sys.stderr.write(u)
>
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> UnicodeEncodeError: 'ascii' codec can't encode characters in position
> 0-2: ordinal not in range(128)
>
> What is file.encoding convention?
> If I want to write a unicode string to a file(-like) that have
> encoding attribute, I should do
> (1) try: file.write(unicode_str),
> (2) except UnicodeEncodeError: file.write(unicode_str.encode
> (file.encoding))
> likelogging?
> It seems agly.

Further to my earlier mail, please have a look at the following
screenshot:

http://imgur.com/FtAi0.png

As you can see, the codepage is set to 1251 (Cyrillic) at the
beginning. A Unicode string is initialised with Cyrillic code points.
Then sys.stdout.encoding shows 'cp1251', but writing the string to it
gives a UnicodeEncodeError. Explicitly encoding the string and writing
it works. Next, we get a wrapper from the codecs module for the same
encoding and use it to wrap sys.stdout. Writing the Unicode string to
the wrapped string works, too.

So the problem is essentially this: if a stream has an encoding
attribute, sometimes it is a wrapped stream which encodes Unicode
(e.g. a stream obtained via the codecs module) and sometimes it is not
(e.g. sys.stdout, sys.stderr).

Regards,

Vinay


From clp2 at rebertia.com  Thu Jul 23 15:52:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 23 Jul 2009 12:52:48 -0700
Subject: effbot.org broken (WAS: Problems in commands.getoutput(cmd) with sox)
Message-ID: <50697b2c0907231252w4715c94di7876b8580cddf170@mail.gmail.com>

On Thu, Jul 23, 2009 at 12:42 PM, Chris Rebert<clp2 at rebertia.com> wrote:
> You can use tabnanny to help diagnose the problem:
> http://74.125.155.132/search?q=cache:QtxvZm3QDLsJ:effbot.org/librarybook/tabnanny.htm+tabnanny&cd=3&hl=en&ct=clnk&gl=us&client=firefox-a

Anyone know what's the deal with effbot.org? It seems to be broken at
present, forcing me to use Google's cached version.
It's a real shame since it has lots of handy Python info.

Cheers,
Chris
-- 
http://blog.rebertia.com


From stef.mientki at gmail.com  Thu Jul 23 15:58:30 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 21:58:30 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <m28wifjm65.fsf@cs.uu.nl>
References: <4A684B56.3020906@gmail.com>
	<4A685A12.4080800@tim.thechases.com>	<mailman.3586.1248354168.8015.python-list@python.org>
	<m28wifjm65.fsf@cs.uu.nl>
Message-ID: <4A68C0E6.90905@gmail.com>

Piet van Oostrum wrote:
>>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:
>>>>>>             
>
>   
>> SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>> SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>> SM>  from OPNAMEN
>> SM>    inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>> SM>    inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>> SM>    inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>> SM>    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>> SM>    inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>> SM> POID_SSID_SCID.POID ) and
>> SM>                                     ( SUBSCHAAL_GEGEVENS.SSID =
>> SM> POID_SSID_SCID.SSID )
>> SM>    inner join SCORES             on SCORES.SCID             =
>> SM> POID_SSID_SCID.SCID
>> SM>    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>> SM>    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>> SM>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>> SM>    and lower ( NAME_ ) = 'fatigue'
>> SM>    and TEST_COUNT in (3,4)
>> SM>    and DATETIME > 39814.0
>> SM>    and SCORE < 30
>>     
>
> 1) Do you have indices on the join fields?
>   
well I'm happily surprised, you came up with this suggestion
- I thought that sqlite created indexes on all primairy key and unique 
fields
- but after explicitly creating the indices, a gained a speed of about a 
factor 10
After checking the database creation, it seemed I forgot to make these 
fields the primary key
so thanks very much.

I gained another factor of 10 speed by updating to version 2.5.5 of 
pysqlite.

cheers,
Stef
> 2) Look at the ANALYZE command
> 3) Look at the EXPLAIN command
>   



From stef.mientki at gmail.com  Thu Jul 23 16:01:16 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Thu, 23 Jul 2009 22:01:16 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <de32cc030907230909u35979708seb76c7193b31105@mail.gmail.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>	
	<4A685F75.10701@gmail.com>
	<de32cc030907230909u35979708seb76c7193b31105@mail.gmail.com>
Message-ID: <4A68C18C.3090605@gmail.com>

David Stanek wrote:
> On Thu, Jul 23, 2009 at 9:02 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
>   
>> btw, I don't know if it's of any importance, the SQL-statement I perform is
>> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>>  from OPNAMEN
>>   inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>>   inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>>   inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>>   inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>>   inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>> POID_SSID_SCID.POID ) and
>>                                    ( SUBSCHAAL_GEGEVENS.SSID =
>> POID_SSID_SCID.SSID )
>>   inner join SCORES             on SCORES.SCID             =
>> POID_SSID_SCID.SCID
>>   inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>>   inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>>   and lower ( NAME_ ) = 'fatigue'
>>   and TEST_COUNT in (3,4)
>>   and DATETIME > 39814.0
>>   and SCORE < 30
>>     
>
> Warning: I suck at SQL and hate it with a passion...
>   
+1,
but I couldn't find anything better.
I guess you have some better suggestions ?
(I looked at Dee, but from my first view, it looks a bit premature)

thanks,
Stef



From nick at craig-wood.com  Thu Jul 23 16:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 15:29:57 -0500
Subject: sqlite3 performance problems only in python
References: <4A684B56.3020906@gmail.com>
	<4A685A12.4080800@tim.thechases.com> <4A685F75.10701@gmail.com>
	<mailman.3602.1248365399.8015.python-list@python.org>
Message-ID: <slrnh6heht.dgi.nick@irishsea.home.craig-wood.com>

David Stanek <dstanek at dstanek.com> wrote:
>  On Thu, Jul 23, 2009 at 9:02 AM, Stef Mientki<stef.mientki at gmail.com> wrote:
> >
> > btw, I don't know if it's of any importance, the SQL-statement I perform is
> > select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
> > ?from OPNAMEN
> > ? inner join POID_VLID ? ? ? ? ?on OPNAMEN.POID ? ? ? ? ? ?= POID_VLID.POID
> > ? inner join VRAAGLST ? ? ? ? ? on VRAAGLST.VLID ? ? ? ? ? = POID_VLID.VLID
> > ? inner join VLID_SSID ? ? ? ? ?on VRAAGLST.VLID ? ? ? ? ? = VLID_SSID.VLID
> > ? inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
> > ? inner join POID_SSID_SCID ? ? on ( OPNAMEN.POID ? ? ? ? ? ?=
> > POID_SSID_SCID.POID ) and
> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?( SUBSCHAAL_GEGEVENS.SSID =
> > POID_SSID_SCID.SSID )
> > ? inner join SCORES ? ? ? ? ? ? on SCORES.SCID ? ? ? ? ? ? =
> > POID_SSID_SCID.SCID
> > ? inner join PID_POID ? ? ? ? ? on OPNAMEN.POID ? ? ? ? ? ?= PID_POID.POID
> > ? inner join PATIENT ? ? ? ? ? ?on PATIENT.PID ? ? ? ? ? ? = PID_POID.PID
> > ?where substr ( lower( NAME) , 1, 6) ?= 'cis20r'
> > ? and lower ( NAME_ ) = 'fatigue'
> > ? and TEST_COUNT in (3,4)
> > ? and DATETIME > 39814.0
> > ? and SCORE < 30
> 
>  Warning: I suck at SQL and hate it with a passion...
> 
>  By using lower() on the left side of the where expressions I believe
>  that you are table scanning. So it is not the size of the data
>  returned, but the size of the data that needs to be scanned.

In all the databases I've used, the like operator has been case
insensitive, so if that is the problem you could use

  NAME like '%cis20r%'  -- not quite the same, but close!
  and NAME_ like 'fatigue'

instead which might be quicker.  Or not ;-)

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From nick at craig-wood.com  Thu Jul 23 16:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 15:29:57 -0500
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system()
	that  doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
Message-ID: <slrnh6hfrp.dgi.nick@irishsea.home.craig-wood.com>

Ville Vainio <vivainio at gmail.com> wrote:
>  Has anyone implementing something like what the subject line
>  indicates?
> 
>  The idea:
> 
>  To run functions that execute a series of system commands without
>  blocking the ui, *and* without adding state machine logic.
> 
>  The syntax would be something like:
> 
>  def work():
> 
>    showstatus("building")
>    r = yield runshell("make")
>    showstatus("installing")
>    r = yield runshell("make install")
>    showstatus("Success")
> 
>  mygui.startwork(work)
>  # returns immediately, runs work() gradually in the background.
> 
>  The catch is that showstatus() would need to be run in the mainloop,
>  so running the whole thing in a thread is a no-go.
> 
>  I imagine runshell() would be implemented in terms of QProcess, or
>  subprocess.Popen/os.system and a worker thread.
> 
>  Anyone done this already, or do I have to roll my own?

You might want to look at twisted, in particular

  http://twistedmatrix.com/trac/wiki/DeferredGenerator

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From nick at craig-wood.com  Thu Jul 23 16:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Thu, 23 Jul 2009 15:29:57 -0500
Subject: Looking for os.listdir() generator
References: <mailman.3584.1248352640.8015.python-list@python.org>
Message-ID: <slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>

Christian Heimes <lists at cheimes.de> wrote:
>  I'm looking for a generator version of os.listdir() for Python 2.5 and
>  newer. I know somebody has worked on it because I've seen a generator
>  version in a posting on some list or blog a while ago. I can't find it
>  anymore. It seems my Google fu is lacking today. All I can find is a
>  very old version of xlistdir. A Cython based solution is appreciated but
>  please no ctypes version.

I posted exactly that yesterday I think ;-)

Note that this has a python part as well as a ctypes part because the
version of ctypes I used doesn't support generators.  I think the
development version does though.

Here is it

--setup.py----------------------------------------------------------

from distutils.core import setup
from distutils.extension import Extension
from Cython.Distutils import build_ext

setup(
    cmdclass = {'build_ext': build_ext},
    ext_modules = [Extension("directory", ["directory.pyx"])]
)

--directory.pyx----------------------------------------------------------

# Cython interface for listdir
# python setup.py build_ext --inplace

import cython

cdef extern from "dirent.h":
    struct dirent:
        char d_name[0]
    ctypedef struct DIR
    DIR *opendir(char *name)
    int closedir(DIR *dirp)
    dirent *readdir(DIR *dirp)

cdef extern from "errno.h":
    int errno

cdef extern from "string.h":
    char *strerror(int errnum)

cdef class Directory:
    """Represents an open directory"""
    
    cdef DIR *handle

    def __init__(self, path):
        self.handle = opendir(path)
        if self.handle is NULL:
            raise OSError(errno, "Failed to open directory: %s" % strerror(errno))

    def readdir(self):
        """Read the next name in the directory"""
        cdef dirent *p
        p = readdir(self.handle)
        if p is NULL:
            return None
        return p.d_name

    def close(self):
        """Close the directory"""
        if self.handle is not NULL:
            closedir(self.handle)
            self.handle = NULL

    def __dealloc__(self):
        self.close()

--listdir.py----------------------------------------------------------

from directory import Directory

def listdir(path):
    """
    A generator to return the names of files in the directory passed in
    """
    d = Directory(path)
    while True:
        name = d.readdir()
        if not name:
            break
        if name not in (".", ".."):
            yield name
    d.close()
    del d

if __name__ == "__main__":
    import sys
    paths = sys.argv[1:]
    if not paths:
        paths = ["."]
    for path in paths:
        print "*** %s ***" % path
        for name in listdir(path):
            print name

------------------------------------------------------------

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From jaime.frio at gmail.com  Thu Jul 23 16:34:21 2009
From: jaime.frio at gmail.com (Jaime Fernandez del Rio)
Date: Thu, 23 Jul 2009 22:34:21 +0200
Subject: installing 2.6 on vista64
In-Reply-To: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
References: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
Message-ID: <97a8f1a70907231334y1fd64890g9c8cee11b1e41f8f@mail.gmail.com>

I have installed the 32 bit 2.6 and the 64 bit 3.1 on my machine
running Vista 64 without any issues.

Which of course has nothing to do with your problem....

On Thu, Jul 23, 2009 at 7:06 PM, DwBear75<dwbear75 at gmail.com> wrote:
> I just downloaded and attempted to install python 2.6.2. ?The
> installer proceeds to do its work then dies, leaving an entry in the
> eventlog:
>
> Windows Installer installed the product. Product Name: Python 2.6.2.
> Product Version: 2.6.2150. Product Language: 1033. Installation
> success or error status: 1602.
>
> Googling for this I wasn't able to narrow the results down to
> something usable. Anyone know of issues and how to fix them installing
> on vista 64 (yes, I have 8 gigs of ram)
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
(\__/)
( O.o)
( > <) Este es Conejo. Copia a Conejo en tu firma y ay?dale en sus
planes de dominaci?n mundial.


From malaclypse2 at gmail.com  Thu Jul 23 16:50:56 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Thu, 23 Jul 2009 16:50:56 -0400
Subject: sqlite3 performance problems only in python
In-Reply-To: <slrnh6heht.dgi.nick@irishsea.home.craig-wood.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<4A685F75.10701@gmail.com>
	<mailman.3602.1248365399.8015.python-list@python.org>
	<slrnh6heht.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <16651e80907231350t554f8603i7e6bb82172169b52@mail.gmail.com>

On Thu, Jul 23, 2009 at 4:29 PM, Nick Craig-Wood<nick at craig-wood.com> wrote:
> In all the databases I've used, the like operator has been case
> insensitive, so if that is the problem you could use

This is not true in all databases! ?Many times, this is something that
is configurable when setting up the database server. ?I'm not sure
what the defaults are, but here at work we have DB/2 and Oracle
servers that are case sensitive, and at least one MSSQL server that is
not.

-- 
Jerry


From laran.evans at gmail.com  Thu Jul 23 16:53:19 2009
From: laran.evans at gmail.com (Laran Evans)
Date: Thu, 23 Jul 2009 13:53:19 -0700 (PDT)
Subject: 2.3 missing on OSX
Message-ID: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>

I just tried to run MacVim on OSX 10.5. It crashed with this:

Dyld Error Message:
  Library not loaded: /System/Library/Frameworks/Python.framework/
Versions/2.3/Python
  Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
MacVim.app/Contents/MacOS/Vim
  Reason: image not found

I posted to the MacVim mailing list and was told that that version of
2.3 should always be available because it comes with the OS.

I don't remember if I removed it for whatever reason at some point or
something. In any case, I have python installed now via MacPorts. I
have version 2.3 and 2.5 both installed.

So my question is, is there a way for me to fix the issue by re-
instating the default 2.3 location or something?

I'm not much of a Python person. So I don't really know where to start
with this one.

Thanks.


From deets at nospam.web.de  Thu Jul 23 17:01:21 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 23 Jul 2009 23:01:21 +0200
Subject: 2.3 missing on OSX
In-Reply-To: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
Message-ID: <7cs1d1F1tbs10U1@mid.uni-berlin.de>

Laran Evans schrieb:
> I just tried to run MacVim on OSX 10.5. It crashed with this:
> 
> Dyld Error Message:
>   Library not loaded: /System/Library/Frameworks/Python.framework/
> Versions/2.3/Python
>   Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
> MacVim.app/Contents/MacOS/Vim
>   Reason: image not found
> 
> I posted to the MacVim mailing list and was told that that version of
> 2.3 should always be available because it comes with the OS.

On my 10.5 machine, it is under the above given path.

> 
> I don't remember if I removed it for whatever reason at some point or
> something. In any case, I have python installed now via MacPorts. I
> have version 2.3 and 2.5 both installed.
> 
> So my question is, is there a way for me to fix the issue by re-
> instating the default 2.3 location or something?

Most probably yes, but not using MacPorts. Those aren't 
framework-builds, and not in the proper location anyway.

I suggest you try & get hold of a copy from another OSX-machine (match 
teh architecture), and just copy it into the needed location.

Diez


From philip at semanchuk.com  Thu Jul 23 17:03:41 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 17:03:41 -0400
Subject: 2.3 missing on OSX
In-Reply-To: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
Message-ID: <FDCC09F2-8423-47F4-A3A0-370CF6249C76@semanchuk.com>


On Jul 23, 2009, at 4:53 PM, Laran Evans wrote:

> I just tried to run MacVim on OSX 10.5. It crashed with this:
>
> Dyld Error Message:
>  Library not loaded: /System/Library/Frameworks/Python.framework/
> Versions/2.3/Python
>  Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
> MacVim.app/Contents/MacOS/Vim
>  Reason: image not found
>
> I posted to the MacVim mailing list and was told that that version of
> 2.3 should always be available because it comes with the OS.

OS X 10.4 shipped with Python 2.3 as the system Python.

OS X 10.5 ships with Python 2.5 as the system Python. 2.3 is not  
available unless you install it yourself. And if you install it  
yourself, I wouldn't put it where MacVim is looking for it because the  
System folder is OS X stuff. If MacVim (or any app) contains a  
hardcoded reference to /System/.../2.3/Python, then it will break on  
OS X 10.5.




From philip at semanchuk.com  Thu Jul 23 17:14:37 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 17:14:37 -0400
Subject: 2.3 missing on OSX
In-Reply-To: <7cs1d1F1tbs10U1@mid.uni-berlin.de>
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
	<7cs1d1F1tbs10U1@mid.uni-berlin.de>
Message-ID: <D36FE426-E50F-4452-BACB-0C0100109F58@semanchuk.com>


On Jul 23, 2009, at 5:01 PM, Diez B. Roggisch wrote:

> Laran Evans schrieb:
>> I just tried to run MacVim on OSX 10.5. It crashed with this:
>> Dyld Error Message:
>>  Library not loaded: /System/Library/Frameworks/Python.framework/
>> Versions/2.3/Python
>>  Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
>> MacVim.app/Contents/MacOS/Vim
>>  Reason: image not found
>> I posted to the MacVim mailing list and was told that that version of
>> 2.3 should always be available because it comes with the OS.
>
> On my 10.5 machine, it is under the above given path.

Diez is correct, please ignore my earlier post on this topic. I have  
2.3 on my machine in that location as well; I didn't look closely  
enough. Apologies for the misinformation.

I'm not answering any more Mac Python questions as I seem to get them  
wrong every time. :-/





From nad at acm.org  Thu Jul 23 17:14:50 2009
From: nad at acm.org (Ned Deily)
Date: Thu, 23 Jul 2009 14:14:50 -0700
Subject: 2.3 missing on OSX
References: <ce6d734d-620e-46c2-acea-8e48a71a93b6@n11g2000yqb.googlegroups.com>
Message-ID: <nad-D059A6.14145023072009@news.gmane.org>

In article 
<ce6d734d-620e-46c2-acea-8e48a71a93b6 at n11g2000yqb.googlegroups.com>,
 Laran Evans <laran.evans at gmail.com> wrote:
> I just tried to run MacVim on OSX 10.5. It crashed with this:
> 
> Dyld Error Message:
>   Library not loaded: /System/Library/Frameworks/Python.framework/
> Versions/2.3/Python
>   Referenced from: /Users/laran/Downloads/MacVim-7_2-stable-1_2/
> MacVim.app/Contents/MacOS/Vim
>   Reason: image not found
> 
> I posted to the MacVim mailing list and was told that that version of
> 2.3 should always be available because it comes with the OS.
> 
> I don't remember if I removed it for whatever reason at some point or
> something. In any case, I have python installed now via MacPorts. I
> have version 2.3 and 2.5 both installed.
> 
> So my question is, is there a way for me to fix the issue by re-
> instating the default 2.3 location or something?

If, in fact, /System/Library/Frameworks/Python.framework/Versions/2.3 is 
empty or missing, you should restore it.   Rule of thumb: everything 
under /System is installed and managed by Apple.  Don't remove things 
from there!  I don't know of a particularly easy way to restore it, 
short of hacking a Leopard installer image or re-installing OS X.  If 
you have an unused external drive or partition, it might be easiest to 
do a vanilla install of Leopard and all software updates, then, from the 
terminal, do a ditto of that directory subtree back to your regular /.

-- 
 Ned Deily,
 nad at acm.org



From __peter__ at web.de  Thu Jul 23 17:20:42 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 23 Jul 2009 23:20:42 +0200
Subject: Problems in commands.getoutput(cmd) with sox
References: <mailman.3618.1248377576.8015.python-list@python.org>
Message-ID: <h4ak72$8vc$02$1@news.t-online.com>

bbarbero at inescporto.pt wrote:

> Hello to all!
> 
> I am a new researcher, new to Python as well, and I have a problem,
> when I try to get commands from sox in a python script. I am going
> crazy, because this code has been working before.. so I dont really
> know whats going on..
> 
> Ive already seen some solutions that match with what I have. I am
> running this:
> 
> 
> 
>          if os.path.splitext(file_au)[1] == ".au":
>            resampled_file_path = os.path.join(resampled_path, file_au)
>             cmd = "sox " + dir_file + " -r 44100 " + resampled_file_path
>             print cmd
> output = commands.getoutput(cmd)
> print output
> 
> What i do, is just to resample a song from dir_file to
> resampled_file_path. As a result of "cmd" I get:
> 
> ....
> sox /Volumes/HAL/Datasets/Audio/gtzan_genres/rock/rock.00097.au -r
> 44100
> 
/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resampled/rock/rock.00097.au
> .....
> 
> If I run this on the command line, it will work perfectly!
> 
> But The program stops at
> 
>   File
> "/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resamplingto44.py",
> line 35
>      output = commands.getoutput(cmd)
>      ^
> IndentationError: unexpected indent
> 
> I dont have any idea, whats going on, I am trying lot of things, but I
> can understand where is the error as it has been running perfectly
> before.
> 
> Any suggestions will be more than welcome! Thanks in advance for your
> help!

You are probably mixing tabs and spaces and have set your editor to display 
a tabsize != 8 spaces.

When you change the tabsize to 8 you will see the inconsistent indentation.

In the future you can avoid such problems by configuring your editor to 
replace one tab with four spaces. Recommended reading:

http://www.python.org/dev/peps/pep-0008/

Peter




From python at mrabarnett.plus.com  Thu Jul 23 17:25:39 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 23 Jul 2009 22:25:39 +0100
Subject: Problems in commands.getoutput(cmd) with sox
In-Reply-To: <20090723212354.5378695qs4beje8a@horde.inescporto.pt>
References: <20090723212354.5378695qs4beje8a@horde.inescporto.pt>
Message-ID: <4A68D553.6090203@mrabarnett.plus.com>

bbarbero at inescporto.pt wrote:
> Hello to all!
> 
> I am a new researcher, new to Python as well, and I have a problem, when 
> I try to get commands from sox in a python script. I am going crazy, 
> because this code has been working before.. so I dont really know whats 
> going on..
> 
> Ive already seen some solutions that match with what I have. I am 
> running this:
> 
> 
> 
>         if os.path.splitext(file_au)[1] == ".au":
>               resampled_file_path = os.path.join(resampled_path, file_au)
>                cmd = "sox " + dir_file + " -r 44100 " + resampled_file_path
>                print cmd
                 ^ extra indent
>         output = commands.getoutput(cmd)
>         print output
> 
> What i do, is just to resample a song from dir_file to 
> resampled_file_path. As a result of "cmd" I get:
> 
> ....
> sox /Volumes/HAL/Datasets/Audio/gtzan_genres/rock/rock.00097.au -r 44100 
> /Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resampled/rock/rock.00097.au 
> 
> .....
> 
> If I run this on the command line, it will work perfectly!
> 
> But The program stops at
> 
>  File 
> "/Volumes/bmorab/Audio_Projecto/Data/gtzan_genres/resamplingto44.py", 
> line 35
>     output = commands.getoutput(cmd)
>     ^
> IndentationError: unexpected indent
> 
> I dont have any idea, whats going on, I am trying lot of things, but I 
> can understand where is the error as it has been running perfectly before.
> 
> Any suggestions will be more than welcome! Thanks in advance for your help!
> 
You need to double-check the indentation.


From gh at ghaering.de  Thu Jul 23 17:27:08 2009
From: gh at ghaering.de (=?ISO-8859-1?Q?Gerhard_H=E4ring?=)
Date: Thu, 23 Jul 2009 23:27:08 +0200
Subject: Creating xml
In-Reply-To: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
References: <a9f39a410907231230g4a8b374am8cc964a9c97a6f74@mail.gmail.com>
Message-ID: <h4akjd$6sn$1@ger.gmane.org>

Greg Lindstrom wrote:
> It's been a while since I've played with XML using Python but I've been
> asked to create XML using data from our postgres database.  Currently we
> are generating XML directly from the database using a set of stored
> procedures but it is too slow (yes, I have numbers).  I have been asked
> to create a routine to generate the XML to see if it will be faster that
> the sprocs (which I think it will be, based on other routines we have
> running).  But I digress...

I write to a cStringIO.StringIO instance to create XML. Like this
(pseudo-code):

class Foo:
    def toxml(self, stream):
        print >> stream, "<foo ... />"

If you're concerned about producing valid XML, you can write tests ;-)

> Using my favorite search engine I see that there is a lot of material on
> Python and XML.  At the risk of starting something (which is not my
> intention), what are my options if I want to create xml?  Ceratinly
> writing my own routine is an option, but I bet there are better ones :-)
> 
> How about if I need/want to parse or process an XML file?

Use lxml. It's blazingly fast and its XPath support makes parsing XML a
snap. If you don't want to depend on anything not in the standard
library, use the etree module. Code will be slightly longer because you
don't have XPath support and performance will be only "ok". Not
"super-fast", like with lxml.

HTH

-- Gerhard



From suruti94 at gmail.com  Thu Jul 23 17:45:41 2009
From: suruti94 at gmail.com (Mohan Parthasarathy)
Date: Thu, 23 Jul 2009 14:45:41 -0700
Subject: Bridging Python and C
Message-ID: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>

Hi,
I am a newbie. It looks like there are quite a few ways to bridge Python and
C. I have a bunch of C code and I just need Python wrappers for it. If i
google for this I get SWIG, Boost etc. And I also see

http://www.python.org/doc/2.5.2/ext/intro.html

What is the recommended way for doing this ?

thanks
mohan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090723/dcb4da17/attachment-0001.html>

From jon at ffconsultancy.com  Thu Jul 23 17:49:13 2009
From: jon at ffconsultancy.com (Jon Harrop)
Date: Thu, 23 Jul 2009 22:49:13 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<h467aq$mfg$1@news.eternal-september.org>
	<72fb4a8d-b160-43c0-87ba-22a0d3768d5f@a37g2000prf.googlegroups.com>
	<h4a7kg$q36$1@news.eternal-september.org>
Message-ID: <npmdnbBIr_YeV_XXnZ2dnUVZ8tpi4p2d@brightview.co.uk>

Raffael Cavallaro wrote:
> Yes, you are missing the joke. The point is that if python is 60x
> slower than C, even if there were not a GIL, it would require running
> the python program on a 60 core machine just reach parity with C. The
> existence of the GIL means that in reality you'd probably need a
> several hundred core machine...

No, OCaml is in the same boat as Python. Spawning a parallel work item takes
20,000x longer in OCaml than in F#. Gathering the results is asymptotically
slower in general. Consequently, for most problems, Python or OCaml running
on an infinite number of cores cannot beat F# running on 2 or more (and I
already have 8) because the overheads are far too high for parallelism to
pay off.

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
http://www.ffconsultancy.com/?u


From lists at cheimes.de  Thu Jul 23 17:53:22 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 23 Jul 2009 23:53:22 +0200
Subject: Bridging Python and C
In-Reply-To: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
References: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
Message-ID: <h4am4i$b7n$1@ger.gmane.org>

Mohan Parthasarathy wrote:
> Hi,
> I am a newbie. It looks like there are quite a few ways to bridge Python and
> C. I have a bunch of C code and I just need Python wrappers for it. If i
> google for this I get SWIG, Boost etc. And I also see
> 
> http://www.python.org/doc/2.5.2/ext/intro.html
> 
> What is the recommended way for doing this ?

I recommend Cython (http://cython.org/). I'm using it on a daily bases
to wrap C libraries.

Christian



From philip at semanchuk.com  Thu Jul 23 17:54:33 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Thu, 23 Jul 2009 17:54:33 -0400
Subject: Bridging Python and C
In-Reply-To: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
References: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
Message-ID: <12D9D99B-6730-4534-BA61-631A4B9B27FE@semanchuk.com>


On Jul 23, 2009, at 5:45 PM, Mohan Parthasarathy wrote:

> Hi,
> I am a newbie. It looks like there are quite a few ways to bridge  
> Python and
> C. I have a bunch of C code and I just need Python wrappers for it.  
> If i
> google for this I get SWIG, Boost etc. And I also see
>
> http://www.python.org/doc/2.5.2/ext/intro.html
>
> What is the recommended way for doing this ?

"Recommended" depends on what you want to accomplish. SWIG, Boost,  
etc. all have pros and cons.

One option you didn't mention is ctypes which is part of the Python  
standard library. It allows you to pass params to C functions. Works  
great for me!


HTH
Philip



From cmpython at gmail.com  Thu Jul 23 17:54:34 2009
From: cmpython at gmail.com (Che M)
Date: Thu, 23 Jul 2009 14:54:34 -0700 (PDT)
Subject: sqlite3 performance problems only in python
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com> 
	<mailman.3586.1248354168.8015.python-list@python.org>
	<m28wifjm65.fsf@cs.uu.nl> 
	<mailman.3621.1248379117.8015.python-list@python.org>
Message-ID: <a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>

On Jul 23, 3:58?pm, Stef Mientki <stef.mien... at gmail.com> wrote:
> Piet van Oostrum wrote:
> >>>>>> Stef Mientki <stef.mien... at gmail.com> (SM) wrote:
>
> >> SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
> >> SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
> >> SM> ?from OPNAMEN
> >> SM> ? ?inner join POID_VLID ? ? ? ? ?on OPNAMEN.POID ? ? ? ? ? ?= POID_VLID.POID
> >> SM> ? ?inner join VRAAGLST ? ? ? ? ? on VRAAGLST.VLID ? ? ? ? ? = POID_VLID.VLID
> >> SM> ? ?inner join VLID_SSID ? ? ? ? ?on VRAAGLST.VLID ? ? ? ? ? = VLID_SSID.VLID
> >> SM> ? ?inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
> >> SM> ? ?inner join POID_SSID_SCID ? ? on ( OPNAMEN.POID ? ? ? ? ? ?=
> >> SM> POID_SSID_SCID.POID ) and
> >> SM> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ( SUBSCHAAL_GEGEVENS.SSID =
> >> SM> POID_SSID_SCID.SSID )
> >> SM> ? ?inner join SCORES ? ? ? ? ? ? on SCORES.SCID ? ? ? ? ? ? =
> >> SM> POID_SSID_SCID.SCID
> >> SM> ? ?inner join PID_POID ? ? ? ? ? on OPNAMEN.POID ? ? ? ? ? ?= PID_POID.POID
> >> SM> ? ?inner join PATIENT ? ? ? ? ? ?on PATIENT.PID ? ? ? ? ? ? = PID_POID.PID
> >> SM> ?where substr ( lower( NAME) , 1, 6) ?= 'cis20r'
> >> SM> ? ?and lower ( NAME_ ) = 'fatigue'
> >> SM> ? ?and TEST_COUNT in (3,4)
> >> SM> ? ?and DATETIME > 39814.0
> >> SM> ? ?and SCORE < 30
>
> > 1) Do you have indices on the join fields?
>
> well I'm happily surprised, you came up with this suggestion
> - I thought that sqlite created indexes on all primairy key and unique
> fields
> - but after explicitly creating the indices, a gained a speed of about a
> factor 10
> After checking the database creation, it seemed I forgot to make these
> fields the primary key
> so thanks very much.
>
> I gained another factor of 10 speed by updating to version 2.5.5 of
> pysqlite.
>
> cheers,
> Stef
>
> > 2) Look at the ANALYZE command
> > 3) Look at the EXPLAIN command
>
>

You might want to consult the SQLite list for questions like this.

Why do you use pysqlite?  I just import sqlite3 in Python 2.5.
What is the advantage of pysqlite?

Che


From longbotham at gmail.com  Thu Jul 23 18:05:34 2009
From: longbotham at gmail.com (Nathan)
Date: Thu, 23 Jul 2009 15:05:34 -0700 (PDT)
Subject: netCDF4 usage issues
Message-ID: <7c26c9b2-4560-4c16-a01a-68db6c206177@i6g2000yqj.googlegroups.com>

I am having issues correctly implementing the multi-file read
functionality in the Python module netCDF4 (whitaker -
http://code.google.com/p/netcdf4-python/).  I am a relative beginner
to Python, so I may be missing something simple.  I've done my best to
follow the example in the documentation at the website referenced
above (reprinted):

>>> from netCDF4 import MFDataset
>>> f = MFDataset('mftest*nc')
>>> print f.variables['x'][:]
[ 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22
23 24
 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
48 49
 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
73 74
 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99]
>>>

Where I attempt to follow the same flow, I don't get the full data set
returned.  I only get a data set for the first file in my list (see
notes in the code below).

>from netCDF4 import MFDataset
>f = MFDataset('E*nc')   # All files I want to read are .nc files in a single directory, each file starting with E
>temp = f.variables['TEMP'][:]
>temp.shape
Out[17]: (8940, 150)  #This is the exact shape of the TEMP variables
array in the first file I need to read verified by an external netCDF
reader application
>f.file_format #There are two files I am trying to read in this example
Out[33]: ['NETCDF3_CLASSIC', 'NETCDF3_CLASSIC']

Does the module only support netcdf4 files? If so, why is it getting
data out of one of the files?  I'm unsure how to trouble shoot this.

Any suggestions would be appreciated.  If this should be posted
elsewhere, please direct me to another list/forum as I didn't find any
directly related to netCDF or this specific netCDF module.  Thank you!


From http  Thu Jul 23 18:06:22 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 15:06:22 -0700
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>
	<pan.2009.07.23.09.37.54.891000@nowhere.com>
Message-ID: <7xk51zm4v5.fsf@ruckus.brouhaha.com>

Nobody <nobody at nowhere.com> writes:
> They also have the advantage that one thread can run while another is
> waiting on disk I/O, which isn't something which can be done with a
> select/poll interface (even if select/poll worked for files, it doesn't
> help for mapped files).

AIO can help with this, but I don't know any language runtimes that
use it right now.  Really, this (and the similar issue of ram cache
misses) is basically why hardware hyperthreading exists too.  To get
processor parallelism you do have to use OS threads, but green threads
are lighter weight and switch faster, so you want to use a combination
of both.  Basically, use about as many OS threads as you have hardware
threads (i.e. CPU cores or hyperthreads), and then assign green
threads to OS threads in your application runtime.


From lists at cheimes.de  Thu Jul 23 18:08:56 2009
From: lists at cheimes.de (Christian Heimes)
Date: Fri, 24 Jul 2009 00:08:56 +0200
Subject: Looking for os.listdir() generator
In-Reply-To: <slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>
References: <mailman.3584.1248352640.8015.python-list@python.org>
	<slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <h4an1o$di6$1@ger.gmane.org>

Nick Craig-Wood wrote:
> Christian Heimes <lists at cheimes.de> wrote:
>>  I'm looking for a generator version of os.listdir() for Python 2.5 and
>>  newer. I know somebody has worked on it because I've seen a generator
>>  version in a posting on some list or blog a while ago. I can't find it
>>  anymore. It seems my Google fu is lacking today. All I can find is a
>>  very old version of xlistdir. A Cython based solution is appreciated but
>>  please no ctypes version.
> 
> I posted exactly that yesterday I think ;-)
> 
> Note that this has a python part as well as a ctypes part because the
> version of ctypes I used doesn't support generators.  I think the
> development version does though.

Thanks Nick!

ctypes? I'm sure you wanted to say Cython :)

If you don't mind I'm going to wrap it up into a nice package and
release it on PyPI.

Christian



From myzoku at gmail.com  Thu Jul 23 18:14:19 2009
From: myzoku at gmail.com (Gordon)
Date: Thu, 23 Jul 2009 15:14:19 -0700 (PDT)
Subject: Gedcom and Genealogy
Message-ID: <5222a601-a128-4892-9a8d-e1942ac9ce4d@e27g2000yqm.googlegroups.com>

We have many small libraries in JAVA or Ruby that need to be ported to
Python.  Actually it's so simple a rewrite is possible too.


From dr.mtarver at ukonline.co.uk  Thu Jul 23 18:20:04 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Thu, 23 Jul 2009 15:20:04 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3609.1248368502.8015.python-list@python.org>
Message-ID: <f3f73975-384b-4860-96f2-10589aa7a6b0@h11g2000yqb.googlegroups.com>

On 23 July, 18:01, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
> On Thu, 23 Jul 2009 08:48:46 -0700 (PDT), Mark Tarver
> <dr.mtar... at ukonline.co.uk> declaimed the following in
> gmane.comp.python.general:
>
> > I have a very strange error. ?I have two test python files test.py and
> > python.py which contain the following code
>
> ? ? ? ? <snip>
>
> > The other fails with a server configuration error. ?Both are running
>
> ? ? ? ? Way out from left field... Have you tried renaming "python.py" to
> some other name?
>
> ? ? ? ? If the server is configured to treat .py as executable files, it
> might be getting confused over "python.py" trying to invoke "python".
> --
> ? ? ? ? Wulfraed ? ? ? ?Dennis Lee Bieber ? ? ? ? ? ? ? KD6MOG
> ? ? ? ? wlfr... at ix.netcom.com ? ? ? ? ? ? wulfr... at bestiaria.com
> ? ? ? ? ? ? ? ? HTTP://wlfraed.home.netcom.com/
> ? ? ? ? (Bestiaria Support Staff: ? ? ? ? ? ? ? web-a... at bestiaria.com)
> ? ? ? ? ? ? ? ? HTTP://www.bestiaria.com/

Yes; tried pyth.py - still failed.

Mark


From dr.mtarver at ukonline.co.uk  Thu Jul 23 18:27:51 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Thu, 23 Jul 2009 15:27:51 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3614.1248369008.8015.python-list@python.org>
Message-ID: <99dbbe65-adcd-4f06-aa8c-2d7fc25bf94c@s15g2000yqs.googlegroups.com>

On 23 July, 18:01, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
> On Thu, 23 Jul 2009 08:48:46 -0700 (PDT), Mark Tarver
> <dr.mtar... at ukonline.co.uk> declaimed the following in
> gmane.comp.python.general:
>
> > The only hint at a difference I can see is that my ftp program says
> > the files are of unequal lengths. ?test.py is 129 bytes long.
> > python.py 134 bytes long.
>
> ? ? ? ? Just a guess...
>
> ? ? ? ? Line endings... <lf> vs <cr><lf>
>
> --
> ? ? ? ? Wulfraed ? ? ? ?Dennis Lee Bieber ? ? ? ? ? ? ? KD6MOG
> ? ? ? ? wlfr... at ix.netcom.com ? ? ? ? ? ? wulfr... at bestiaria.com
> ? ? ? ? ? ? ? ? HTTP://wlfraed.home.netcom.com/
> ? ? ? ? (Bestiaria Support Staff: ? ? ? ? ? ? ? web-a... at bestiaria.com)
> ? ? ? ? ? ? ? ? HTTP://www.bestiaria.com/

Is that linefeed + ctrl or what?  I can't pick up any difference
reading the files char by char in Lisp.  How do you find the
difference?

Mark


From stef.mientki at gmail.com  Thu Jul 23 18:29:40 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Fri, 24 Jul 2009 00:29:40 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<mailman.3586.1248354168.8015.python-list@python.org>	<m28wifjm65.fsf@cs.uu.nl>
	<mailman.3621.1248379117.8015.python-list@python.org>
	<a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>
Message-ID: <4A68E454.8040909@gmail.com>

Che M wrote:
> On Jul 23, 3:58 pm, Stef Mientki <stef.mien... at gmail.com> wrote:
>   
>> Piet van Oostrum wrote:
>>     
>>>>>>>> Stef Mientki <stef.mien... at gmail.com> (SM) wrote:
>>>>>>>>                 
>>>> SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>>>> SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>>>> SM>  from OPNAMEN
>>>> SM>    inner join POID_VLID          on OPNAMEN.POID            = POID_VLID.POID
>>>> SM>    inner join VRAAGLST           on VRAAGLST.VLID           = POID_VLID.VLID
>>>> SM>    inner join VLID_SSID          on VRAAGLST.VLID           = VLID_SSID.VLID
>>>> SM>    inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>>>> SM>    inner join POID_SSID_SCID     on ( OPNAMEN.POID            =
>>>> SM> POID_SSID_SCID.POID ) and
>>>> SM>                                     ( SUBSCHAAL_GEGEVENS.SSID =
>>>> SM> POID_SSID_SCID.SSID )
>>>> SM>    inner join SCORES             on SCORES.SCID             =
>>>> SM> POID_SSID_SCID.SCID
>>>> SM>    inner join PID_POID           on OPNAMEN.POID            = PID_POID.POID
>>>> SM>    inner join PATIENT            on PATIENT.PID             = PID_POID.PID
>>>> SM>  where substr ( lower( NAME) , 1, 6)  = 'cis20r'
>>>> SM>    and lower ( NAME_ ) = 'fatigue'
>>>> SM>    and TEST_COUNT in (3,4)
>>>> SM>    and DATETIME > 39814.0
>>>> SM>    and SCORE < 30
>>>>         
>>> 1) Do you have indices on the join fields?
>>>       
>> well I'm happily surprised, you came up with this suggestion
>> - I thought that sqlite created indexes on all primairy key and unique
>> fields
>> - but after explicitly creating the indices, a gained a speed of about a
>> factor 10
>> After checking the database creation, it seemed I forgot to make these
>> fields the primary key
>> so thanks very much.
>>
>> I gained another factor of 10 speed by updating to version 2.5.5 of
>> pysqlite.
>>
>> cheers,
>> Stef
>>
>>     
>>> 2) Look at the ANALYZE command
>>> 3) Look at the EXPLAIN command
>>>       
>>     
>
> You might want to consult the SQLite list for questions like this.
>   
thanks,
but because the same SQL-statement in Delphi performed well,
I thought it was a problem with the Python implementation.
> Why do you use pysqlite?  I just import sqlite3 in Python 2.5.
> What is the advantage of pysqlite?
>   
it's 10 .. 15 times faster then sqlite3 delivered with pyton 2.5.
AFAIK it's nothing different, just a newer version.

cheers,
Stef
> Che
>   



From pavlovevidence at gmail.com  Thu Jul 23 18:39:35 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 15:39:35 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org> 
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com> 
	<pan.2009.07.23.09.37.54.891000@nowhere.com>
Message-ID: <36db2930-b4c9-4308-a267-a41703160580@h21g2000yqa.googlegroups.com>

On Jul 23, 2:37?am, Nobody <nob... at nowhere.com> wrote:
> On Wed, 22 Jul 2009 15:17:52 -0700, Carl Banks wrote:
> > So do all these OSes have some kind of __mega_unifying_poll system
> > call that works for anything that might possibly block, that you can
> > exploit from a user process?
>
> Threads ;)

Yeah, well that was kind of my point, you'd need native threads to do
some of this.

Jean-Paul Calderone seemed to be suggesting that it was possible to
wait for events on sockets, pipes, and IPC semaphores at the same.  I
pointed out that it isn't possible with well-known I/O polling calls
(like select), so there must be some other way, and I was wondering
what it was.

He's a proponent of Twisted, which is a major async framework, and I'd
have to figure that once or twice they've encounted issues like "how
to poll both a semaphore and a socket at the same time", so maybe
they've found a good solution to it.


Carl Banks


From __peter__ at web.de  Thu Jul 23 18:49:47 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 00:49:47 +0200
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3614.1248369008.8015.python-list@python.org>
	<99dbbe65-adcd-4f06-aa8c-2d7fc25bf94c@s15g2000yqs.googlegroups.com>
Message-ID: <h4ape3$n4b$01$1@news.t-online.com>

Mark Tarver wrote:

> On 23 July, 18:01, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
>> On Thu, 23 Jul 2009 08:48:46 -0700 (PDT), Mark Tarver
>> <dr.mtar... at ukonline.co.uk> declaimed the following in
>> gmane.comp.python.general:
>>
>> > The only hint at a difference I can see is that my ftp program says
>> > the files are of unequal lengths.  test.py is 129 bytes long.
>> > python.py 134 bytes long.
>>
>> Just a guess...
>>
>> Line endings... <lf> vs <cr><lf>
>>
>> --
>> Wulfraed        Dennis Lee Bieber               KD6MOG
>> wlfr... at ix.netcom.com             wulfr... at bestiaria.com
>> HTTP://wlfraed.home.netcom.com/
>> (Bestiaria Support Staff:               web-a... at bestiaria.com)
>> HTTP://www.bestiaria.com/
> 
> Is that linefeed + ctrl or what?  I can't pick up any difference
> reading the files char by char in Lisp.  How do you find the
> difference?

carriage-return + linefeed

That's the Windows convention for end-of-line markers. Unix uses linefeed 
only.

If you are on Windows you have to open the file in binary mode to see the 
difference:

>>> open("python.py", "rb").read()
'#!/usr/bin/python\r\nprint "Content-type: 
text/html"\r\nprint\r\nprint"<html>"\r\nprint "<center>Hello, 
Linux.com!</center>"\r\nprint "</html>"'
>>> open("test.py", "rb").read()
'#!/usr/bin/python\nprint "Content-type: text/html"\nprint\nprint 
"<html>"\nprint "<center>Hello, Linux.com!</center>"\nprint "</html>"'
>>>

\n denotes a newline (chr(10))
\r denotes a cr (chr(13))

You can fix the line endings with

open(outfile, "wb").writelines(open(infile, "rU"))

Here "U" denotes "universal newline" mode which recognizes "\r", "\n", and 
"\r\n" as line endings and translates all of these into "\n". "wb" means 
"write binary" which does no conversion. Therefore you'll end up with 
outfile following the Unix convention.

Peter



From lists at cheimes.de  Thu Jul 23 18:54:40 2009
From: lists at cheimes.de (Christian Heimes)
Date: Fri, 24 Jul 2009 00:54:40 +0200
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A684B56.3020906@gmail.com>
References: <4A684B56.3020906@gmail.com>
Message-ID: <4A68EA30.5060006@cheimes.de>

Stef Mientki schrieb:
> hello,
> 
> until now I used only small / simple databases in Python with sqlite3.
> Now I've a large and rather complex database.
> 
> The most simple query (with just a result of 100 rows),
> takes about 70 seconds.
> And all that time is consumed in "cursor.fetchall"
> 
> Using the same database in Delphi,
> using the same query,
> takes less than 5 seconds (including displaying the full table in a grid).

Side note:

Since you are coming from Delphi you are probably glad to hear that
Firebird (formally known as Borland InterBase) is well supported. The
kinterbasdb DBA provides a DBA 2.0 compatible interface plus lots of
additional Firebird specific features. You might be better of using
Firebird if you need large and complex databases.

With Firebird you can then create a lower case index:

  CREATE INDEX idx_lower_name ON table COMPUTED BY (LOWER(name));

and use it to query the table for lower case names with:

  SELECT ... FROM table t WHERE LOWER(t.name) STARTING WITH LOWER(:query)

or maybe:

  SELECT ... FROM table t WHERE t.name STARTING WITH LOWER(:query) PLAN
JOIN (t INDEX(idx_lower_name));

Firebird 2.1 supports even more useful features to join on columns
without falling back to a full table scan like UNICODE_CI.

Christian


From david at boddie.org.uk  Thu Jul 23 18:58:19 2009
From: david at boddie.org.uk (David Boddie)
Date: Fri, 24 Jul 2009 00:58:19 +0200
Subject: Pyserial and pyQt
References: <11eb9b7a-3bf2-4f1e-92f1-fa9ba0cfe859@k30g2000yqf.googlegroups.com>
	<h45inh$ofk$1@get-news01.get.basefarm.net>
	<70e4ebae-908f-4f3a-a96a-6fa0a7a7887a@y19g2000yqy.googlegroups.com>
	<mailman.3572.1248336905.8015.python-list@python.org>
Message-ID: <h4apub$gov$1@get-news01.get.basefarm.net>

On Thursday 23 July 2009 10:13, Dennis Lee Bieber wrote:

> On Wed, 22 Jul 2009 10:32:51 -0700 (PDT), Seth <king.seth at gmail.com>
> declaimed the following in gmane.comp.python.general:
> 
>> Thanks for the response.  I have gone through a lot of the tutorials.
>> All of them(that I saw) seem to just deal will event-based
>> applications ie calculator, image viewer, etc.  How do I run pyserial
>> in the background and pass the information to PyQT and refresh the
>> screen?  Is there a way to have pyserial run in another thread and
>> pass the information to the UI?
>>
> So far as I've experienced (which isn't all that much), most all GUI
> frameworks support some method of defining either: 1) a work routine
> which will be called whenever the input event queue is empty -- work
> routines should be coded to do a very short, fast, bit of processing and
> return, so the event dispatcher can continue (collect one character at a
> time, or one line using a non-blocking I/O operation; or use a thread to
> collect and post via a Queue) (wx.EVT_IDLE [bind to your idle handler] &
> wx.WakeUpIdle() [call from thread after posting to queue]);

I think I can say that idle processing isn't a common idiom in PyQt
applications. After all, you can't guarantee that your application will be
idle or be able to use up idle time in a way that you can rely on, and
perhaps it isn't a good situation to be in if your framework is using up
CPU time by idling.

> 2) a timed-event which the dispatcher can call at periodic intervals (use
> a thread to collect lines from the serial port, post the lines via a
> Queue, and have the timed event check for queued data) (wx.Timer() );

In PyQt, the easiest way to do this is with a timer, connecting its
timeout() signal to a slot (method) to perform some processing. A widget
class might be adapted to do this in the following way:

  class MyWindow(QWidget):
    def __init__(self):
      QWidget.__init__(self)
      # ... other initialisation ...
      
      timer = QTimer(self)
      timer.timeout.connect(self.processData) # PyQt 4.5 signal notation
      timer.start(100)                        # every 100 milliseconds
    
    def processData(self):
      # Do your processing here.

There are various ways to use timers with PyQt, but this is a fairly simple
pattern to use.

> 3) a callback interface to the GUI event dispatcher which can be invoked
> from a separate thread (wx.CallAfter() )

I think at this point I would recommend using a separate thread. The idiom
for using threads with PyQt is quite simple, though it helps to go with the
framework and use QThread instead of Python's thread class.

> You'll have to track down the equivalent QT functions (I have to
> confess, I found the above from "wxPython in Action"; my last real GUI
> coding that needed such was nearly 20 years ago, using xt and DECWindows
> for the interface, and GKS on X for the data drawing, emulating an
> archaic Ramtek graphics engine command set. The idle/work routine
> collected commands sent via VMS mailbox to the "display" and generated
> GKS operations for them).

The people demand screenshots! ;-)

David


From timro21 at gmail.com  Thu Jul 23 19:02:23 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 16:02:23 -0700 (PDT)
Subject: integer square roots
Message-ID: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>

I wish to process billions of 100-digit numbers and test if each has
an integer square root.  What's the most efficient way to do this?


From davea at ieee.org  Thu Jul 23 19:03:14 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 23 Jul 2009 19:03:14 -0400
Subject: strange python scripting error
In-Reply-To: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
Message-ID: <4A68EC32.4090907@ieee.org>

Mark Tarver wrote:
> I have a very strange error.  I have two test python files test.py and
> python.py which contain the following code
>
> #!/usr/bin/python
> print "Content-type: text/html"
> print
> print "<html>"
> print "<center>Hello, Linux.com!</center>"
> print "</html>"
>
> One file (test.py) works; you call it up and it shows a web page with
>
> Hello, Linux.com
>
> The other fails with a server configuration error.  Both are running
> under Linux, same server, same permissions.  Running a character scan
> shows that both files contain the same printable characters and are
> therefore typographically identical.   They are absolutely the same.
>
> The only hint at a difference I can see is that my ftp program says
> the files are of unequal lengths.  test.py is 129 bytes long.
> python.py 134 bytes long.
>
> A zipped folder containing both files is at
>
> www.lambdassociates.org/weird.zip
>
> Any ideas welcome.
>
> Mark
>
>   
Easiest explanation is that python.py has Windows-style newlines.  In 
other words, each line ends with 0d0a, rather than the Unix convention 
of 0a.

If your server is Unix-based, it can't handle that first line, since it 
has an illegal character (0d) following the

#!/usr/bin/python

line.  Convert it to Unix line-endings.

DaveA


From gagsl-py2 at yahoo.com.ar  Thu Jul 23 19:14:07 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 23 Jul 2009 20:14:07 -0300
Subject: Detect target name in descriptor __set__ method
References: <op.uxgdm5z7x6zn5v@lepton.softlabbsas.com.ar>
	<op.uxg2j7b5a8ncjz@gnudebst>
	<mailman.3560.1248307583.8015.python-list@python.org>
	<74cd3059-cd88-418b-8444-766a125d93c3@y4g2000prf.googlegroups.com>
Message-ID: <op.uxjmtteix6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 10:19:33 -0300, DG <dangets at gmail.com> escribi?:
> On Jul 22, 6:05?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>> En Wed, 22 Jul 2009 11:01:09 -0300, Rhodri James ?
>> <rho... at wildebst.demon.co.uk> escribi?:
>>
>> > On Wed, 22 Jul 2009 06:02:55 +0100, Gabriel Genellina ?
>> > <gagsl-... at yahoo.com.ar> wrote:
>>
>> >> class X(object):
>> >> ? ?foo = descriptor()
>>
>> >> x = X()
>> >> x.foo = "value"
>>
> You might've already thought of this (and it is annoying), but you
> could pass the name through the descriptor's init method.  I believe
> this is the only way besides assigning a metaclass that will look for
> that type of descriptor upon class creation and set the descriptor's
> name at that time.
>
> class A(object):
>     def __init__(self, attr_name):
>         self._name = attr_name
>     def __set__(self, instance, value):
>         self.instance.__dict__[self._name] = value
>         # or something like that...
>
> class B(object):
>     foo = A('foo')

Thanks, this seems to be the less "magical" solution. I don't like having  
to repeat the attribute name, but nothing is perfect...
And thanks to Rainer Mansfeld too; looking up the matching attribute may  
be useful in other cases.

-- 
Gabriel Genellina



From pavlovevidence at gmail.com  Thu Jul 23 19:30:54 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 16:30:54 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
	<7xws60p7kk.fsf@ruckus.brouhaha.com>
Message-ID: <6a3f1211-b551-4012-904c-0ed0a2c9f6f8@o32g2000yqm.googlegroups.com>

On Jul 22, 5:27?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > I don't think your fantasy async-only all-green-thread langauge
> > implementation is possible anyway.
>
> Erlang and GHC both work like that, quite successfully:
>
> ?http://shootout.alioth.debian.org/gp4/benchmark.php?test=threadring&l...

I am not suggesting that you can't do a lot of things with async I/O.
But can you do *everything* that native threads can do?  I don't think
so.

So when you asked:

"Why is that [native threading] such an advantage?  Green threads work
fine if you just
organize the i/o system to never block."

Well, the answer is they don't always work fine.  Just organizing the
I/O system never to block won't cut it, since things other than I/O
block.  For green threads to work fine all the time you have to be
able organize your entire system never to block, and I don't think
it's possible on the common OSes in use today.  Until that happens,
there will always be advantages to being able to use native threads on
a single core.


> > How would you wait on a pipe in one thread, a socket in another, a
> > semaphore in a third? ?
>
> You can select on pipes and sockets, I think. ?Not sure about
> semaphores. ?

So you made a claim that "green threads work fine", and rhetorically
suggested that native threads had no advantages, yet you're not even
100% sure you can select on both pipes and sockets (both common forms
of I/O), let alone semaphores?

[You can select on sockets and pipes in Unix, not in Windows, although
on Windows I think there are other ways to do it besides the select
call.]


> > (Are there any popular OSes that offer a unified polling interface to
> > all possible synchronizations?) ?And what do you do about drivers or
> > libraries that make underlying blocking calls? ?What if you have a
> > busy calculation going on in the background?
>
> I don't think the concept of "drivers" applies to user-mode programs.
> For FFI calls you would use an OS thread.

That's contrary to the hypothesis, isn't it?

>?The language runtime
> switches between busy computation threads on a timer tick.

This would seem to result in a tradeoff between performance and low-
latency.  Well that happens at the OS-level too but the OS can respond
to interrupts and task switch between timer ticks at finer intervals.
Back in my DOS days I wrote user programs that responded to I/O
interrupts, but it doesn't seem to be common practice in modern OSes
to easily allow this.


And Paul, if I'm being a little hard on you here, it's not that I'm
taking issue with your own claim so much as with your dismissal of
mine.


Carl Banks


From scriptlearner at gmail.com  Thu Jul 23 19:39:29 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Thu, 23 Jul 2009 16:39:29 -0700 (PDT)
Subject: passing data to a liburl2 opener object
Message-ID: <89de6563-1016-461b-87b6-090754ca224b@r2g2000yqm.googlegroups.com>

I have prepared my headers and data for a HTTP POST message; however,
I am not sure how to pass the data to the opener.  Can you guys
provide some suggestions?  Thanks.


proxy_handler = urllib2.ProxyHandler({'http': 'http://my.proxy.com:
3128/'})
opener = urllib2.build_opener(proxy_handler)

url = "http://sample.company.com:9999/service?"

headers['Content-Type'] = 'multipart/form-data; boundary=%s' %
myBoundar
headers['Cookie'] = 'somevalidcookiecontents'
#there is an opener.addheaders method for adding headers
data = multipart_encode(myDict)
#how to pass data to the opener???


With the codes above, I need to send out a HTTP POST like the
following one:

POST http://sample.company.com:9999/service?
Content-Type: multipart/form-data;
boundary=---------------------------1234

---------------------------1234
Content-Disposition: form-data; name="picture"

PICTURE contents here
---------------------------1234
Content-Disposition: form-data; name="id"

whateverid
---------------------------1234--


From shai at platonix.com  Thu Jul 23 19:51:43 2009
From: shai at platonix.com (Shai)
Date: Thu, 23 Jul 2009 16:51:43 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<8e71092f-d57b-4784-8874-3dd19bd5c06b@d32g2000yqh.googlegroups.com>
	<87ljmogglz.fsf@benfinney.id.au>
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <056f629b-aa63-458a-ae16-ac40a759e446@h11g2000yqb.googlegroups.com>

On Jul 17, 10:52?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
>
> When the decorator is called, the function object is just a function
> object, not a method, so there is no concept of "what class it is
> destined for".
>

... which points to the better solution: use a descriptor. With the
doc_inherit decorator defined below, one may write

class Foo(object):
    def foo(self):
        "Frobber"
        pass

class Bar(Foo):
    @doc_inherit
    def foo(self):
        pass

and it appears to work. The code below is a little longish because we
need to do slightly different things when called for a class and for
an instance. But there's no need to repeat the parent name, no need
to look into namespaces (which, as you said, is probably messy and
fragile), and it seems pretty readable, too.

from functools import wraps

class DocInherit(object):
    """
    Docstring inheriting method descriptor

    The class itself is also used as a decorator
    """

    def __init__(self, mthd):
        self.mthd = mthd
        self.name = mthd.__name__

    def __get__(self, obj, cls):
        if obj:
            return self.get_with_inst(obj, cls)
        else:
            return self.get_no_inst(cls)

    def get_with_inst(self, obj, cls):

        overridden = getattr(super(cls, obj), self.name, None)

        @wraps(self.mthd, assigned=('__name__','__module__'))
        def f(*args, **kwargs):
            return self.mthd(obj, *args, **kwargs)

        return self.use_parent_doc(f, overridden)

    def get_no_inst(self, cls):

        for parent in cls.__mro__[1:]:
            overridden = getattr(parent, self.name, None)
            if overridden: break

        @wraps(self.mthd, assigned=('__name__','__module__'))
        def f(*args, **kwargs):
            return self.mthd(*args, **kwargs)

        return self.use_parent_doc(f, overridden)

    def use_parent_doc(self, func, source):
        if source is None:
            raise NameError, ("Can't find '%s' in parents"%self.name)
        func.__doc__ = source.__doc__
        return func

doc_inherit = DocInherit

Combining docstrings (as suggested by Jean-Paul Calderone), and
taking proper care of classmethods and staticmethods, are left
as an exercise to the reader.

Have fun,
Shai.


From davea at ieee.org  Thu Jul 23 19:52:22 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 23 Jul 2009 19:52:22 -0400
Subject: Bridging Python and C
In-Reply-To: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
References: <89dd3da60907231445r9dc4bd5jad1dbbdcfb490032@mail.gmail.com>
Message-ID: <4A68F7B6.2020101@ieee.org>

Mohan Parthasarathy wrote:
> Hi,
> I am a newbie. It looks like there are quite a few ways to bridge Python and
> C. I have a bunch of C code and I just need Python wrappers for it. If i
> google for this I get SWIG, Boost etc. And I also see
>
> http://www.python.org/doc/2.5.2/ext/intro.html
>
> What is the recommended way for doing this ?
>
> thanks
> mohan
>
>   
I think the real question to ask is what form is your C code in.  If 
you're in Windows, and it's compiled into DLL's with documented exports, 
then I'd start by using ctypes to access a few of the exports.  If that 
seems too hard, you might try SWIG or another automated tool, to parse 
the headers and generate wrappers.  But if you haven't done it first by 
hand, you might find the automated tools very hard to figure out.

DaveA


From http  Thu Jul 23 19:57:10 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 16:57:10 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net>
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com>
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
	<7xws60p7kk.fsf@ruckus.brouhaha.com>
	<6a3f1211-b551-4012-904c-0ed0a2c9f6f8@o32g2000yqm.googlegroups.com>
Message-ID: <7x8wifymuh.fsf@ruckus.brouhaha.com>

Carl Banks <pavlovevidence at gmail.com> writes:
> > I don't think the concept of "drivers" applies to user-mode programs.
> > For FFI calls you would use an OS thread.
> That's contrary to the hypothesis, isn't it?

Yeah, it would have been better to say, green threads are ok for most
typical forms of i/o concurrency, but OS threads are still necessary
for some things.  An FFI call in particular isn't exactly under the
control of your language's runtime system; it has to be treated
more like an external program.

OS thread?switching is much more expensive than green thread
switching, so it's still preferable to use green threads when
possible.

> >?The language runtime switches between busy computation threads on
> >?a timer tick.
> This would seem to result in a tradeoff between performance and low-
> latency. 

GHC appears to use a 100 hz timer, which I'd expect to be fast enough
for interactive applications while still not causing too much cpu
load.  I don't know if it has a way to assign priorities to
microthreads (e.g. if you have one running your program's GUI) though.

I don't think either Python or GHC can implement hard-real-time
latency because they both use stop-the-world garbage collection.
E.g. in Python, releasing the last reference to a large list or dict
can take a long time.

> And Paul, if I'm being a little hard on you here, it's not that I'm
> taking issue with your own claim so much as with your dismissal of
> mine.

Well, the issue was why Python uses native threads pervasively.  As
far as I can tell, it's just an implementation artifact that has no
really compelling justification.


From mensanator at aol.com  Thu Jul 23 20:11:54 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 23 Jul 2009 17:11:54 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
Message-ID: <73b8529d-23f4-41b4-a6cd-9f191f74bcd4@y19g2000yqy.googlegroups.com>

On Jul 23, 6:02?pm, timro21 <timr... at gmail.com> wrote:
> I wish to process billions of 100-digit numbers and test if each has
> an integer square root. ?What's the most efficient way to do this?

Use gmpy.

>>> import gmpy
>>> help(gmpy.sqrt)

Help on built-in function sqrt in module gmpy:

sqrt(...)
    sqrt(x): returns the integer, truncated square root of x, i.e. the
    largest y such that x>=y*y. x must be an mpz, or else gets coerced
    to one; further, x must be >= 0.

>>> p = 10**100

>>> p1 = gmpy.next_prime(p)

>>> p1
mpz
(10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000267)

>>> gmpy.sqrt(p1)
mpz(100000000000000000000000000000000000000000000000000)




From mensanator at aol.com  Thu Jul 23 20:17:53 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 23 Jul 2009 17:17:53 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<73b8529d-23f4-41b4-a6cd-9f191f74bcd4@y19g2000yqy.googlegroups.com>
Message-ID: <ad3518c1-655c-428b-81b1-e1d8b23384c1@o6g2000yqj.googlegroups.com>

On Jul 23, 7:11?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 23, 6:02?pm, timro21 <timr... at gmail.com> wrote:
>
> > I wish to process billions of 100-digit numbers and test if each has
> > an integer square root. ?What's the most efficient way to do this?
>
> Use gmpy.
>
> >>> import gmpy
> >>> help(gmpy.sqrt)
>
> Help on built-in function sqrt in module gmpy:
>
> sqrt(...)
> ? ? sqrt(x): returns the integer, truncated square root of x, i.e. the
> ? ? largest y such that x>=y*y. x must be an mpz, or else gets coerced
> ? ? to one; further, x must be >= 0.
>
> >>> p = 10**100
> >>> p1 = gmpy.next_prime(p)
> >>> p1
>
> mpz
> (10000000000000000000000000000000000000000000000000000000000000000000000000?000000000000000000000000267)
>
> >>> gmpy.sqrt(p1)
>
> mpz(100000000000000000000000000000000000000000000000000)

Duh. I completely misread this. I thought you wanted the square root,
not IF it had a square root that's an integer.

Sorry about that.

Try this, instead:

>>> gmpy.sqrtrem(p1)
(mpz(100000000000000000000000000000000000000000000000000), mpz(267))

It has a non-zero remainder, so it's not an integer square root.


From aahz at pythoncraft.com  Thu Jul 23 20:25:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 23 Jul 2009 17:25:16 -0700
Subject: Help understanding the decisions *behind* python?
References: <534b1c540907200927g4cb7011bpe58249d2517d1b5d@mail.gmail.com>
	<mailman.3616.1248369685.8015.python-list@python.org>
Message-ID: <h4av1c$6eh$1@panix3.panix.com>

In article <mailman.3616.1248369685.8015.python-list at python.org>,
Mark Lawrence  <breamoreboy at yahoo.co.uk> wrote:
>
>Sorry if this has been discussed and I've missed it, but how about 
>memory allocation.  An immutable tuple has a fixed memory allocation 
>whereas that for the mutable list must be liable to change.  You might 
>like to look at the recent thread on this ng 'List insertion cost' and 
>follow the links to Raymond Hettinger's power point presentation.

Not only that, but lists use more memory, period, for any given number of
elements because the overallocation permits amortized constant time for
appends.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From aahz at pythoncraft.com  Thu Jul 23 20:27:35 2009
From: aahz at pythoncraft.com (Aahz)
Date: 23 Jul 2009 17:27:35 -0700
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
	<EgE9m.507$646.499@nwrddc01.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
Message-ID: <h4av5n$p1l$1@panix3.panix.com>

In article <mailman.3561.1248307942.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>
>NLMPI

What?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From mensanator at aol.com  Thu Jul 23 20:30:34 2009
From: mensanator at aol.com (Mensanator)
Date: Thu, 23 Jul 2009 17:30:34 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<73b8529d-23f4-41b4-a6cd-9f191f74bcd4@y19g2000yqy.googlegroups.com> 
	<ad3518c1-655c-428b-81b1-e1d8b23384c1@o6g2000yqj.googlegroups.com>
Message-ID: <e8394cb1-9630-4e4e-8770-6cf70766ea1e@b15g2000yqd.googlegroups.com>

On Jul 23, 7:17?pm, Mensanator <mensana... at aol.com> wrote:
> On Jul 23, 7:11?pm, Mensanator <mensana... at aol.com> wrote:
>
>
>
>
>
> > On Jul 23, 6:02?pm, timro21 <timr... at gmail.com> wrote:
>
> > > I wish to process billions of 100-digit numbers and test if each has
> > > an integer square root. ?What's the most efficient way to do this?
>
> > Use gmpy.
>
> > >>> import gmpy
> > >>> help(gmpy.sqrt)
>
> > Help on built-in function sqrt in module gmpy:
>
> > sqrt(...)
> > ? ? sqrt(x): returns the integer, truncated square root of x, i.e. the
> > ? ? largest y such that x>=y*y. x must be an mpz, or else gets coerced
> > ? ? to one; further, x must be >= 0.
>
> > >>> p = 10**100
> > >>> p1 = gmpy.next_prime(p)
> > >>> p1
>
> > mpz
> > (10000000000000000000000000000000000000000000000000000000000000000000000000??000000000000000000000000267)
>
> > >>> gmpy.sqrt(p1)
>
> > mpz(100000000000000000000000000000000000000000000000000)
>
> Duh. I completely misread this. I thought you wanted the square root,
> not IF it had a square root that's an integer.
>
> Sorry about that.
>
> Try this, instead:
>
> >>> gmpy.sqrtrem(p1)
>
> (mpz(100000000000000000000000000000000000000000000000000), mpz(267))
>
> It has a non-zero remainder, so it's not an integer square root.

There's also

   is_square(...)
        is_square(x): returns 1 if x is a perfect square, else 0.
        x must be an mpz, or else gets coerced to one.



From http  Thu Jul 23 20:35:27 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 17:35:27 -0700
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
Message-ID: <7x4ot2zzn4.fsf@ruckus.brouhaha.com>

timro21 <timro21 at gmail.com> writes:
> I wish to process billions of 100-digit numbers and test if each has
> an integer square root.  What's the most efficient way to do this?

Is this a homework problem?  If not, may I ask what the application is?

I think the basic answer is 1) use the law of quadratic reciprocity to
eliminate a lot of the inputs quickly (for example, just looking at
the low 8 bits of an input number should eliminate about 5/6th of
them); 2) use GMP and Newton's method to check the rest.
http://cr.yp.to/papers/powers.pdf has some advice about how to do
that.

sci.crypt might be another good place to ask this question.


From songofacandy at gmail.com  Thu Jul 23 20:49:26 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Thu, 23 Jul 2009 17:49:26 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>
Message-ID: <784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>

>  What is the encoding of sys.stderr in your example?
Sorry, I missed. It is cp932

> So the problem is essentially this: if a stream has an encoding
> attribute, sometimes it is a wrapped stream which encodes Unicode
> (e.g. a stream obtained via the codecs module) and sometimes it is not
> (e.g. sys.stdout, sys.stderr).

Yes! I confused by it.

>> The encoding that this file uses. When Unicode strings are written to a file,
>>  they will be converted to byte strings using this encoding. In addition,
>> when the file is connected to a terminal, the attribute gives the encoding
>> that the terminal is likely to use

I feel this doc means "file object with encoding attribute encodes
unicode
regardless it is tty or not" and sys.stdout/stderr defies convention.

If this doc means "file object encodes unicode if it isn't tty.", I
should write
like below::

if not afile.isatty():
    if getattr(afile, "encoding") is not None:
        afile.write(unicode_str)
elif getattr(afile, "encoding") is not None:
    afile.write(unicode_str.encode(afile.encoding))
else:
    afile.write(unicode_str.encode(fallback_encoding)) # utf8,
defaultencoding, preferedencoding, ...


"Writing unicode to a file(-like)" is a simple requirement.
Does python have any simple resolution for it?


From rui.maciel at gmail.com  Thu Jul 23 20:52:00 2009
From: rui.maciel at gmail.com (Rui Maciel)
Date: Fri, 24 Jul 2009 01:52 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
Message-ID: <4a6905b0$0$27110$a729d347@news.telepac.pt>

fft1976 wrote:

> How do you explain that something as inferior as Python beat Lisp in
> the market place despite starting 40 years later.

Probably due to similar reasons that lead php to become remotely relevant.


Rui Maciel


From timro21 at gmail.com  Thu Jul 23 21:00:20 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 18:00:20 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
Message-ID: <fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>

On Jul 24, 10:35?am, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> timro21 <timr... at gmail.com> writes:
> > I wish to process billions of 100-digit numbers and test if each has
> > an integer square root. ?What's the most efficient way to do this?
>
> Is this a homework problem? ?If not, may I ask what the application is?
>
> I think the basic answer is 1) use the law of quadratic reciprocity to
> eliminate a lot of the inputs quickly (for example, just looking at
> the low 8 bits of an input number should eliminate about 5/6th of
> them); 2) use GMP and Newton's method to check the rest.http://cr.yp.to/papers/powers.pdfhas some advice about how to do
> that.
>
> sci.crypt might be another good place to ask this question.

Homework?  Gosh no.  I have several number theory applications which
need to know (quickly) whether particular very large numbers are
perfect squares.  Since I asked this in this newsgroup I guess I
assumed that responses wuld relate specifically to how to do this
efficiently *and accurately* in Python.  Sorry if I wasn't clear.


From dstanek at dstanek.com  Thu Jul 23 21:23:06 2009
From: dstanek at dstanek.com (David Stanek)
Date: Thu, 23 Jul 2009 21:23:06 -0400
Subject: sqlite3 performance problems only in python
In-Reply-To: <4A68E454.8040909@gmail.com>
References: <4A684B56.3020906@gmail.com> <4A685A12.4080800@tim.thechases.com>
	<mailman.3586.1248354168.8015.python-list@python.org>
	<m28wifjm65.fsf@cs.uu.nl>
	<mailman.3621.1248379117.8015.python-list@python.org>
	<a6e84dba-f417-48bd-9d7a-b4da66b62f0e@d32g2000yqh.googlegroups.com>
	<4A68E454.8040909@gmail.com>
Message-ID: <de32cc030907231823n29ab86c8n7cdba1832be059dd@mail.gmail.com>

On Thu, Jul 23, 2009 at 6:29 PM, Stef Mientki<stef.mientki at gmail.com> wrote:
>
> but because the same SQL-statement in Delphi performed well,
> I thought it was a problem with the Python implementation.

Same SQL, but were you also using Sqlite in Delphi?

-- 
David
blog: http://www.traceback.org
twitter: http://twitter.com/dstanek


From http  Thu Jul 23 21:51:01 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 18:51:01 -0700
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
Message-ID: <7xzlaudf22.fsf@ruckus.brouhaha.com>

timro21 <timro21 at gmail.com> writes:
> Homework?  Gosh no.  I have several number theory applications which
> need to know (quickly) whether particular very large numbers are
> perfect squares.  Since I asked this in this newsgroup I guess I
> assumed that responses wuld relate specifically to how to do this
> efficiently *and accurately* in Python.  Sorry if I wasn't clear.

comp.lang.python is a good place to get answers about Python.  It's
probably not such a good source of answers about computational number
theory.  Also, Python is more about productivity than speed, so
answers involving Python may not be the most efficient possible
answers.  One obvious point though is that GMP/gmpy is pretty simple
to use from Python and will be several times faster than Python's
built in longs.  Also, as Mensanator pointed out, GMP has built-in
functions that will help you with precise checks (I'd forgotten or not
known about them).  I still think you'd get a speedup from first
filtering out obviously non-square candidates before resorting to
multi-precision arithmetic.  Some other fairly simple optimization may
be possible too.

I asked about the application mainly because I wondered if you had
realtime requirements, whether you were going to have to keep doing
this problem with new numbers, etc.  If you just have a 1-off task of
checking a few billion numbers, you could probably do it in a few days
with Python on a workstation using some fairly simple code.  If you
want to check billions of numbers per minute, or if what you really
want is to check trillions of numbers rather than billions, then it's
worth pursuing fancier methods.  Another issue is the source of the
numbers.  E.g. maybe there is a way to program a graphics accelerator
to turn a number into a list of residues mod a bunch of small primes
in parallel and get a fast, near-certain test if the inputs are
random, but that approach could be fooled if the numbers were
concocted by a possible adversary.


From casevh at gmail.com  Thu Jul 23 22:04:50 2009
From: casevh at gmail.com (casevh)
Date: Thu, 23 Jul 2009 19:04:50 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
Message-ID: <aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>

> comp.lang.python is a good place to get answers about Python. ?It's
> probably not such a good source of answers about computational number
> theory. ?Also, Python is more about productivity than speed, so
> answers involving Python may not be the most efficient possible
> answers. ?One obvious point though is that GMP/gmpy is pretty simple
> to use from Python and will be several times faster than Python's
> built in longs. ?Also, as Mensanator pointed out, GMP has built-in
> functions that will help you with precise checks (I'd forgotten or not
> known about them). ?I still think you'd get a speedup from first
> filtering out obviously non-square candidates before resorting to
> multi-precision arithmetic. ?Some other fairly simple optimization may
> be possible too.
>
gmpy.is_square() is quite fast. On a older 32-bit Linux box, it can
test approximately 400,000 100-digits numbers per second. The time
includes conversion from a string. If the numbers are already Python
longs, it can check 800,000 per second. Checking a billion is not
unreasonable.

casevh


From http  Thu Jul 23 22:48:12 2009
From: http (Paul Rubin)
Date: 23 Jul 2009 19:48:12 -0700
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
Message-ID: <7xocra7q4z.fsf@ruckus.brouhaha.com>

casevh <casevh at gmail.com> writes:
> gmpy.is_square() is quite fast. On a older 32-bit Linux box, it can
> test approximately 400,000 100-digits numbers per second. The time
> includes conversion from a string. If the numbers are already Python
> longs, it can check 800,000 per second. Checking a billion is not
> unreasonable.

Wow, that is pretty impressive.  A look at the code shows it uses
quite a few optimizations:

http://sage.math.washington.edu/home/novoselt/gmp-4.2.4/mpn/perfsqr.c


From songofacandy at gmail.com  Thu Jul 23 23:10:10 2009
From: songofacandy at gmail.com (Naoki INADA)
Date: Thu, 23 Jul 2009 20:10:10 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com> 
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>
Message-ID: <ebe8014b-5323-4cb6-99ec-5612b390130a@d9g2000prh.googlegroups.com>

>
> Yes! I confused by it.

s/I confused/I am confused/

> "Writing unicode to a file(-like)" is a simple requirement.
> Does python have any simple resolution for it?

s/resolution/solution/

Sorry about my poor English.


From pavlovevidence at gmail.com  Thu Jul 23 23:11:23 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 20:11:23 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com> 
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<1cethsrrw8h6k$.9ty7j7u7zovn.dlg@40tude.net>
	<8bbba0b8-073b-4a43-8954-d5fe7b2f40ee@o15g2000yqm.googlegroups.com>
	<uRr9m.6558$ze1.5162@news-server.bigpond.net.au>
	<rNOSPAMon-7C2B71.09362722072009@news.albasani.net> 
	<4e05ee59-db96-4bfc-9828-b11374446ac6@e18g2000vbe.googlegroups.com> 
	<7xskgobpnv.fsf@ruckus.brouhaha.com>
	<5993d986-cda2-4dd3-b288-69467a68f949@o6g2000yqj.googlegroups.com>
	<7xfxco35g8.fsf@ruckus.brouhaha.com>
	<f3b79b1c-af91-4136-a2ff-b92afd473a2d@e18g2000vbe.googlegroups.com>
	<7xws60p7kk.fsf@ruckus.brouhaha.com>
	<6a3f1211-b551-4012-904c-0ed0a2c9f6f8@o32g2000yqm.googlegroups.com>
	<7x8wifymuh.fsf@ruckus.brouhaha.com>
Message-ID: <d154c2d9-82c2-4897-815b-2c675b9684f6@q11g2000yqi.googlegroups.com>

On Jul 23, 4:57?pm, Paul Rubin <http://phr... at NOSPAM.invalid> wrote:
> Carl Banks <pavlovevide... at gmail.com> writes:
> > > I don't think the concept of "drivers" applies to user-mode programs.
> > > For FFI calls you would use an OS thread.
> > That's contrary to the hypothesis, isn't it?
>
> Yeah, it would have been better to say, green threads are ok for most
> typical forms of i/o concurrency, but OS threads are still necessary
> for some things. ?An FFI call in particular isn't exactly under the
> control of your language's runtime system; it has to be treated
> more like an external program.
>
> OS thread?switching is much more expensive than green thread
> switching, so it's still preferable to use green threads when
> possible.

That is reasonable.  Thank you.


> > And Paul, if I'm being a little hard on you here, it's not that I'm
> > taking issue with your own claim so much as with your dismissal of
> > mine.
>
> Well, the issue was why Python uses native threads pervasively. ?As
> far as I can tell, it's just an implementation artifact that has no
> really compelling justification.

Probably for this reason: "Because then they didn't have to arrange
for the I/O to never block."


Carl Banks


From timro21 at gmail.com  Thu Jul 23 23:30:25 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 20:30:25 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
Message-ID: <2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>


Thanks to all!

Tim


From pavlovevidence at gmail.com  Thu Jul 23 23:51:02 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Thu, 23 Jul 2009 20:51:02 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
Message-ID: <a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>

On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
> fft1976 wrote:
> > How do you explain that something as inferior as Python beat Lisp in
> > the market place despite starting 40 years later.
>
> Probably due to similar reasons that lead php to become remotely relevant.

Well, the only reason PHP became relevant because it was an easy to
deploy solution in a single application domain, the web, that happened
to explode.

The same thing happened to Python.

Oh, wait, no it didn't.


Carl Banks


From tundra at tundraware.com  Thu Jul 23 23:51:26 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Thu, 23 Jul 2009 22:51:26 -0500
Subject: integer square roots
In-Reply-To: <2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
Message-ID: <rmnnj6-f922.ln1@ozzie.tundraware.com>

timro21 wrote:
> Thanks to all!
> 
> Tim

While we're at it, would you mind saying more about what exactly you're
doing - Inquiring Math Dorks (tm) want to know ...

-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From icebergwtf at gmail.com  Thu Jul 23 23:58:04 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Fri, 24 Jul 2009 11:58:04 +0800
Subject: extract c/cpp include file with regular expression
In-Reply-To: <slrnh6he16.dgi.nick@irishsea.home.craig-wood.com>
References: <mailman.3597.1248363967.8015.python-list@python.org>
	<slrnh6he16.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <4314c1f70907232058t4d295a25t86ba11d90e15001d@mail.gmail.com>

Thanks, Philip Semanchuk and Nick Craig-Wood!
My goal is gather informations from cpp sources and generate cross
referenced html files (as more detail as fine)
So I think " missing some unusual cases" might be acceptable, but
informations you introduced make me more interests to dig things out
:)
I know some programs like doxygen do such things, but I can learn much
by doing this than simply write configuration files.

cheers!

tiefeng wu
2009-07-24


From rurpy at yahoo.com  Fri Jul 24 00:19:52 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Thu, 23 Jul 2009 21:19:52 -0700 (PDT)
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
	<zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com>
Message-ID: <e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com>

Nick Dumas wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Agreed. Two string.split()s, first at the semi-colon and then at the
> equal sign, will yield you your value, without having to fool around
> with regexes.
>
> On 7/23/2009 9:23 AM, Mark Lawrence wrote:
>> scriptlearner at gmail.com wrote:
>>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>>> will like to take out the values (valuea, valueb, and valuec).  How do
>>> I do that in Python?  The group method will only return the matched
>>> part.  Thanks.
>>>
>>> p = re.compile('#a=*;b=*;c=*;')
>>> m = p.match(line)
>>>         if m:
>>>              print m.group(),
>>
>> IMHO a regex for this is overkill, a combination of string methods such
>> as split and find should suffice.

You're saying that something like the following
is better than the simple regex used by the OP?

[untested]
values = []
parts = line.split(';')
if len(parts) != 4: raise SomeError()
for p, expected in zip (parts[-1], ('#a','b','c')):
    name, x, value = p.partition ('=')
    if name != expected or x != '=':
        raise SomeError()
    values.append (value)
print values[0], values[1], values[2]

Blech, not in my book.  The regex checks the
format of the string, extracts the values, and
does so very clearly.  Further, it is easily
adapted to other similar formats, or evolutionary
changes in format.  It is also (once one is
familiar with regexes -- a useful skill outside
of Python too) easier to get right (at least in
a simple case like this.)

The only reason I can think of to prefer
a split-based solution is if this code were
performance-critical in that I would expect
the split code to be faster (although I don't
know that for sure.)

This is a perfectly fine use of a regex.


From d at vidr.cc  Fri Jul 24 00:27:10 2009
From: d at vidr.cc (David Roberts)
Date: Fri, 24 Jul 2009 14:27:10 +1000
Subject: OverflowError in RLock.acquire()
Message-ID: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>

Hi,

I'm trying to port a Python application to Windows, and I'm getting
the following error (which did not occur when running on Linux):

Exception in thread Thread-4:
Traceback (most recent call last):
  File "C:\Python26\lib\threading.py", line 525, in __bootstrap_inner
    self.run()
  File "C:\Documents and Settings\David\My
Documents\pyzui\pyzui\tileprovider.py", line 97, in run
    self.__tilecache[tile_id] = Tile(tile)
  File "C:\Documents and Settings\David\My
Documents\pyzui\pyzui\tilecache.py", line 165, in __setitem__
    with self.__lock:
  File "C:\Python26\lib\threading.py", line 115, in acquire
    me = current_thread()
  File "C:\Python26\lib\threading.py", line 803, in currentThread
    return _active[_get_ident()]
OverflowError: can't convert negative value to unsigned long

Where __lock is an RLock object.

The error only occurs for a single class (which is derived from the
TileProvider class in tileprovider.py, which in turn is derived from
threading.Thread), which would lead me to believe that there's an
error in my code, but the traceback doesn't help much, and I haven't
been able to find any similar problems with google.

Any help would be appreciated.

--
David Roberts
http://da.vidr.cc/


From d at vidr.cc  Fri Jul 24 00:41:01 2009
From: d at vidr.cc (David Roberts)
Date: Fri, 24 Jul 2009 14:41:01 +1000
Subject: OverflowError in RLock.acquire()
In-Reply-To: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>
References: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>
Message-ID: <fe0877110907232141k58f14160r17a23d82fd852714@mail.gmail.com>

I forgot to mention, Python version is 2.6.2.

--
David Roberts
http://da.vidr.cc/



On Fri, Jul 24, 2009 at 14:27, David Roberts<d at vidr.cc> wrote:
> Hi,
>
> I'm trying to port a Python application to Windows, and I'm getting
> the following error (which did not occur when running on Linux):
>
> Exception in thread Thread-4:
> Traceback (most recent call last):
> ?File "C:\Python26\lib\threading.py", line 525, in __bootstrap_inner
> ? ?self.run()
> ?File "C:\Documents and Settings\David\My
> Documents\pyzui\pyzui\tileprovider.py", line 97, in run
> ? ?self.__tilecache[tile_id] = Tile(tile)
> ?File "C:\Documents and Settings\David\My
> Documents\pyzui\pyzui\tilecache.py", line 165, in __setitem__
> ? ?with self.__lock:
> ?File "C:\Python26\lib\threading.py", line 115, in acquire
> ? ?me = current_thread()
> ?File "C:\Python26\lib\threading.py", line 803, in currentThread
> ? ?return _active[_get_ident()]
> OverflowError: can't convert negative value to unsigned long
>
> Where __lock is an RLock object.
>
> The error only occurs for a single class (which is derived from the
> TileProvider class in tileprovider.py, which in turn is derived from
> threading.Thread), which would lead me to believe that there's an
> error in my code, but the traceback doesn't help much, and I haven't
> been able to find any similar problems with google.
>
> Any help would be appreciated.
>
> --
> David Roberts
> http://da.vidr.cc/
>


From timro21 at gmail.com  Fri Jul 24 00:43:48 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 21:43:48 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
	<rmnnj6-f922.ln1@ozzie.tundraware.com>
Message-ID: <b3eb02ce-90a6-4479-a127-c737eabc1c4d@q40g2000prh.googlegroups.com>

Hi Tim, sure, I'm looking at the perfect cuboid problem.

I've just spent a couple of very frustrating hours.  Given that I'm in
my 50's but have the brain of a retarded 3-year-old, can someone
please explain what I have to do to download gmpy to use with
ActivePython 2.6 on a Windows system?  I downloaded (or so I thought)
GMPY 1.04 from http://code.google.com/p/gmpy/ but all the files look
way too small...and then how do I import it into a Python
program...I'm sure I could do this if it wasn't for my extreme
stupidity...


From casevh at gmail.com  Fri Jul 24 01:12:23 2009
From: casevh at gmail.com (casevh)
Date: Thu, 23 Jul 2009 22:12:23 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
	<rmnnj6-f922.ln1@ozzie.tundraware.com>
	<b3eb02ce-90a6-4479-a127-c737eabc1c4d@q40g2000prh.googlegroups.com>
Message-ID: <0fc47aab-eb53-4e0a-be6d-9736883db888@i8g2000pro.googlegroups.com>

On Jul 23, 9:43?pm, timro21 <timr... at gmail.com> wrote:
> Hi Tim, sure, I'm looking at the perfect cuboid problem.
>
> I've just spent a couple of very frustrating hours. ?Given that I'm in
> my 50's but have the brain of a retarded 3-year-old, can someone
> please explain what I have to do to download gmpy to use with
> ActivePython 2.6 on a Windows system? ?I downloaded (or so I thought)
> GMPY 1.04 fromhttp://code.google.com/p/gmpy/but all the files look
> way too small...and then how do I import it into a Python
> program...I'm sure I could do this if it wasn't for my extreme
> stupidity...

You should just download the Windows installer from the Downloads tab.
I would recommend version 1.10 since it should be faster and fixes
some bugs in 1.04. The direct link is

http://gmpy.googlecode.com/files/gmpy-1.10-beta.win32-py2.6.exe

Just run the installer and it should automatically detect your
existing Python installation. The executable is small. ;-)

casevh

p.s. If you're using a 64-bit Windows system, let me know and I'll
step you through the manual process.


From Scott.Daniels at Acm.Org  Fri Jul 24 01:20:27 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Thu, 23 Jul 2009 22:20:27 -0700
Subject: Issue combining gzip and subprocess
In-Reply-To: <m2fxcol75g.fsf@cs.uu.nl>
References: <mailman.3472.1248192725.8015.python-list@python.org>
	<m2eisam153.fsf@cs.uu.nl>
	<2YednUGQxvntgfrXnZ2dnUVZ_hWdnZ2d@pdx.net>
	<m2fxcol75g.fsf@cs.uu.nl>
Message-ID: <XrednR3Zov9Y3_TXnZ2dnUVZ_vGdnZ2d@pdx.net>

Piet van Oostrum wrote:
>>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) schreef:
> ...
>> SDD> Or even:
>> SDD>     proc = subprocess.Popen(['ls','-la'], stdout=subprocess.PIPE)
>> SDD>     with gzip.open(filename, 'w') as dest:
>> SDD>         for line in iter(proc.stdout, ''):
>> SDD>             f.write(line)
> 
> If it would work.
> 
> 1) with gzip... is not supported in Python < 3.1
> 2) for line in iter(proc.stdout), i.e. no second argument.
> 3) dest <==> f should be the same identifier.
> 
> Lesson: if you post code either: 
> - test it and copy verbatim from your test, or
> - write a disclaimer

Totally chagrined and embarassed.
Chastisement absorbed and acknowledged.

--Scott David Daniels
Scott.Daniels at Acm.Org



From timro21 at gmail.com  Fri Jul 24 01:36:42 2009
From: timro21 at gmail.com (timro21)
Date: Thu, 23 Jul 2009 22:36:42 -0700 (PDT)
Subject: integer square roots
References: <1646c39f-67a5-45e9-a9ca-f54e4cd7996f@c2g2000yqi.googlegroups.com>
	<7x4ot2zzn4.fsf@ruckus.brouhaha.com>
	<fb7f79be-9219-43a1-b17d-a4d1238717a9@t13g2000yqt.googlegroups.com>
	<7xzlaudf22.fsf@ruckus.brouhaha.com>
	<aee7521f-463f-4fd1-9af8-aef9c9c30f7c@d4g2000yqa.googlegroups.com>
	<7xocra7q4z.fsf@ruckus.brouhaha.com>
	<2b4f9c35-f429-4488-89e5-aaa05bc9d4b7@k13g2000prh.googlegroups.com>
	<rmnnj6-f922.ln1@ozzie.tundraware.com>
	<b3eb02ce-90a6-4479-a127-c737eabc1c4d@q40g2000prh.googlegroups.com>
	<0fc47aab-eb53-4e0a-be6d-9736883db888@i8g2000pro.googlegroups.com>
Message-ID: <4132e60e-f586-42d1-b0fc-460aecf6a474@d9g2000prh.googlegroups.com>


Bloody 'ell - thanks.   :-)




From girish.cfc at gmail.com  Fri Jul 24 02:11:11 2009
From: girish.cfc at gmail.com (Girish)
Date: Thu, 23 Jul 2009 23:11:11 -0700 (PDT)
Subject: Registering DLL
Message-ID: <071d3f78-a14b-4ea1-96fd-0f10d9dc2b80@d36g2000prb.googlegroups.com>

Hello,

I am facing a problem while registering DLL(Dspace.dll).. I am getting
an error saying: "DLLRegisterServer inDspace.dll Failed. Return Code:
0x80040201"

I am using following piece of code to generate DLL:

########################################################

# This setup script builds a single-file Python inprocess COM server.
from distutils.core import setup
import py2exe
import sys

# If run without args, build executables, in quiet mode.
if len(sys.argv) == 1:
    sys.argv.append("py2exe")
    sys.argv.append("-q")

class Target:
    def __init__(self, **kw):
        self.__dict__.update(kw)
        # for the versioninfo resources
        self.version = "1.0"
        self.company_name = "None"
        self.copyright = "None"
        self.name = "API"

interp = Target(
    description = "COM server module",
    # what to build.  For COM servers, the module name (not the
    # filename) must be specified!
    modules = ["Dspace"],
    #script = ["Dspace"],
    # we only want the inproc server.
    create_exe = True,
    )

excludes = ["pywin", "pywin.debugger", "pywin.debugger.dbgcon",
            "pywin.dialogs", "pywin.dialogs.list", 'email.Generator',
'email.Iterators', 'email.Utils']

options = {
    "bundle_files": 1,
    "ascii": 1, # to make a smaller executable, don't include the
encodings
    "compressed": 1, # compress the library archive
    "excludes": excludes, # COM stuff we don't want
    }

setup(
    options = {"py2exe": options},
    zipfile = None, # append zip-archive to the executable.
    com_server = [interp],
    )
################################################################

I am trying to generate a DLL from Python COM server module. I am able
to register the module by running the python code, but when I generate
a DLL and then try to register it using Regsvr32 command, I am getting
above mentioned error

Please help me resolve this issue.

-Girish


From pfeldman at verizon.net  Fri Jul 24 02:35:43 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Thu, 23 Jul 2009 23:35:43 -0700 (PDT)
Subject: len() should always return something
Message-ID: <24639361.post@talk.nabble.com>


Some aspects of the Python design are remarkably clever, while others leave
me perplexed. Here's an example of the latter: Why does len() give an error
when applied to an int or float? len() should always return something; in
particular, when applied to a scalar, it should return a value of 1. Of
course, I can define my own function like this:

def mylen(x):
   if isinstance(x,int) or isinstance(x,float): return 1
   return len(x)

But, this shouldn't be necessary.
-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24639361.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From deets at nospam.web.de  Fri Jul 24 02:57:44 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 08:57:44 +0200
Subject: len() should always return something
In-Reply-To: <mailman.3644.1248417347.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <7ct4b8F29mednU1@mid.uni-berlin.de>

Dr. Phillip M. Feldman schrieb:
> Some aspects of the Python design are remarkably clever, while others leave
> me perplexed. Here's an example of the latter: Why does len() give an error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1. Of
> course, I can define my own function like this:
> 
> def mylen(x):
>    if isinstance(x,int) or isinstance(x,float): return 1
>    return len(x)
> 
> But, this shouldn't be necessary.

Can you show some example of where that is actually making a piece of 
code more elegant?

Diez


From clp2 at rebertia.com  Fri Jul 24 03:02:28 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 00:02:28 -0700
Subject: len() should always return something
In-Reply-To: <24639361.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com>
Message-ID: <50697b2c0907240002i1721d7a4y54d618782ca1a071@mail.gmail.com>

On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Some aspects of the Python design are remarkably clever, while others leave
> me perplexed. Here's an example of the latter: Why does len() give an error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1. Of
> course, I can define my own function like this:
>
> def mylen(x):
> ? if isinstance(x,int) or isinstance(x,float): return 1
> ? return len(x)
>
> But, this shouldn't be necessary.

The problem is that redefining len()/length/size that way would
violate several principles of Python's design (The "Zen" of Python -
http://www.python.org/dev/peps/pep-0020/).

Specifically:
- Explicit is better than implicit.
- Special cases aren't special enough to break the rules.
- Errors should never pass silently.
- In the face of ambiguity, refuse the temptation to guess.

If you'd explain the situation that prompts you to find this
redefinition necessary, I'm sure someone can suggest a better
approach.

Cheers,
Chris
-- 
http://blog.rebertia.com


From __peter__ at web.de  Fri Jul 24 03:07:03 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 09:07:03 +0200
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <h4bmif$cfg$02$1@news.t-online.com>

Dr. Phillip M. Feldman wrote:

> Some aspects of the Python design are remarkably clever, while others
> leave me perplexed. Here's an example of the latter: Why does len() give
> an error when applied to an int or float? len() should always return
> something; in particular, when applied to a scalar, it should return a
> value of 1. Of course, I can define my own function like this:
> 
> def mylen(x):
>    if isinstance(x,int) or isinstance(x,float): return 1
>    return len(x)
> 
> But, this shouldn't be necessary.

Python should not blur the distinction between vectors an scalars like that. 
Instead of trying to be clever you should pass a vector with a single item 
and send mylen() to /dev/null.

On a general note, I think one of Python's strengths is that it consistently 
/avoids/ this kind of cleverness.

A prominent example is the handling of "1" + 1.

Peter



From nick at craig-wood.com  Fri Jul 24 03:29:57 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Fri, 24 Jul 2009 02:29:57 -0500
Subject: Looking for os.listdir() generator
References: <mailman.3584.1248352640.8015.python-list@python.org>
	<slrnh6hfcc.dgi.nick@irishsea.home.craig-wood.com>
	<mailman.3633.1248386949.8015.python-list@python.org>
Message-ID: <slrnh6ini2.m6i.nick@irishsea.home.craig-wood.com>

Christian Heimes <lists at cheimes.de> wrote:
>  Nick Craig-Wood wrote:
> > Christian Heimes <lists at cheimes.de> wrote:
> >>  I'm looking for a generator version of os.listdir() for Python 2.5 and
> >>  newer. I know somebody has worked on it because I've seen a generator
> >>  version in a posting on some list or blog a while ago. I can't find it
> >>  anymore. It seems my Google fu is lacking today. All I can find is a
> >>  very old version of xlistdir. A Cython based solution is appreciated but
> >>  please no ctypes version.
> > 
> > I posted exactly that yesterday I think ;-)
> > 
> > Note that this has a python part as well as a ctypes part because the
> > version of ctypes I used doesn't support generators.  I think the
> > development version does though.
> 
>  Thanks Nick!
> 
>  ctypes? I'm sure you wanted to say Cython :)

Er, yes!

>  If you don't mind I'm going to wrap it up into a nice package and
>  release it on PyPI.

Yes thats fine with me!

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From wilk at flibuste.net  Fri Jul 24 04:04:03 2009
From: wilk at flibuste.net (William Dode)
Date: 24 Jul 2009 08:04:03 GMT
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
	<mailman.3613.1248368814.8015.python-list@python.org>
Message-ID: <4a696af3$0$442$426a74cc@news.free.fr>

On 23-07-2009, Christian Tismer wrote:
> On 7/17/09 4:11 AM, Bearophile wrote:
>> Very good, thank you. I'll try it when I can.
>>
>> Is Psyco3 going to borrow/steal some ideas/code from Unladen Swallow?
>
> Psyco3: nice typo! :-)
>
> Well, I haven't so far found a new idea there that I'd want
> to borrow and did not know from PyPy, before.
> Wasn't the project plan saying the opposite, borrowing
> some ideas from psyco? :-)
> http://code.google.com/p/unladen-swallow/wiki/ProjectPlan

How do you see the futur of psyco when unladen-swallow will grab the 
best of psyco (if they can !) ?

Wait and see ?

Anyway, thanks a lot for your work that we can use NOW !


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From hendrik at microcorp.co.za  Fri Jul 24 04:13:02 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 24 Jul 2009 10:13:02 +0200
Subject: Gedcom and Genealogy
In-Reply-To: <5222a601-a128-4892-9a8d-e1942ac9ce4d@e27g2000yqm.googlegroups.com>
References: <5222a601-a128-4892-9a8d-e1942ac9ce4d@e27g2000yqm.googlegroups.com>
Message-ID: <200907241013.02795.hendrik@microcorp.co.za>

On Friday 24 July 2009 00:14:19 Gordon wrote:
> We have many small libraries in JAVA or Ruby that need to be ported to
> Python.  Actually it's so simple a rewrite is possible too.

Is this:

1 - A question?
2 - A job offer?
3 - A piece of random news?

- Hendrik


From mwawrzyczek at gmail.com  Fri Jul 24 04:35:52 2009
From: mwawrzyczek at gmail.com (marekw2143)
Date: Fri, 24 Jul 2009 01:35:52 -0700 (PDT)
Subject: Adding method from one class to another class or to instance of 
	another class
Message-ID: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>

Hi,

I have one class (A) that has defined method createVars. I would like
to add that method to class B
The code looks like this:


class A(object):
   def createVars(self):
      self.v1 = 1
      self.v2 = 3
      pass

class B(object):
   pass


I don't want to use inheritance (because class A has many methods
defined that class B doesn't need).
When I try the folloowing:


B.createVars = C.createVars
B().createVars()


then the following error occurs:
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unbound method createVars() must be called with A instance
as first argument (got nothing instead)

When I try to add the createVars method to instance of B:

>>> b=B()
>>> b.createVars = new.instancemethod(A.createVars, b, B)
>>> b.createVars
<bound method B.createVars of <__main__.B object at 0x7f6330cc4a90>>
>>> b.createVars()



Then the following error raises:


Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unbound method createVars() must be called with A instance
as first argument (got B instance instead)



How can I solve this problem?

Regards,
Marek


From Slaunger at gmail.com  Fri Jul 24 04:38:37 2009
From: Slaunger at gmail.com (Slaunger)
Date: Fri, 24 Jul 2009 01:38:37 -0700 (PDT)
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
Message-ID: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>

OS: Win XP SP3, 32 bit
Python 2.5.4

Hi I have run into some problems with allocating numpy.memmaps
exceeding and accumulated size of about 2 GB. I have found out that
the real problem relates to numpy.memmap using mmap.mmap

I've written a small test program to illustrate it:

import itertools
import mmap
import os

files = []
mmaps = []
file_names= []
mmap_cap=0
bytes_per_mmap = 100 * 1024 ** 2
try:
    for i in itertools.count(1):
        file_name = "d:/%d.tst" % i
        file_names.append(file_name)
        f = open(file_name, "w+b")
        files.append(f)
        mm = mmap.mmap(f.fileno(), bytes_per_mmap)
        mmaps.append(mm)
        mmap_cap += bytes_per_mmap
        print "Created %d writeable mmaps containing %d MB" % (i,
mmap_cap/(1024**2))

#Clean up
finally:
    print "Removing mmaps..."
    for mm, f, file_name in zip(mmaps, files, file_names):
        mm.close()
        f.close()
        os.remove(file_name)
    print "Done..."


which creates this output

Created 1 writeable mmaps containing 100 MB
Created 2 writeable mmaps containing 200 MB
....
Created 17 writeable mmaps containing 1700 MB
Created 18 writeable mmaps containing 1800 MB
Removing mmaps...
Done...
Traceback (most recent call last):
  File "C:\svn-sandbox\research\scipy\scipy\src\com\terma\kha
\mmaptest.py", line 16, in <module>
    mm = mmap.mmap(f.fileno(), bytes_per_mmap)
WindowsError: [Error 8] Not enough storage is available to process
this command

There is more than 25 GB of free space on drive d: at this stage.

Is it a bug or a "feature" of the 32 bit OS?

I am surprised about it as I have not found any notes about these
kinds of limitations in the documentation.

I am in dire need of these large memmaps for my task, and it is not an
option to change OS due to other constraints in the system.

Is there anything I can do about it?

Best wishes,
Kim


From manu3d at gmail.com  Fri Jul 24 04:55:03 2009
From: manu3d at gmail.com (Emanuele D'Arrigo)
Date: Fri, 24 Jul 2009 01:55:03 -0700 (PDT)
Subject: import vs imp and friends.
References: <9ee16eda-403c-4d62-b9a4-59b5d387c39a@h21g2000yqa.googlegroups.com>
Message-ID: <e5c53078-6878-424a-9996-335ff2fc4427@k19g2000yqn.googlegroups.com>

Christian, Robert, thank you both for the replies, much appreciated.

Manu


From vinay_sajip at yahoo.co.uk  Fri Jul 24 05:14:13 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Fri, 24 Jul 2009 02:14:13 -0700 (PDT)
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com> 
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com> 
	<ebe8014b-5323-4cb6-99ec-5612b390130a@d9g2000prh.googlegroups.com>
Message-ID: <61b029e2-494f-4c87-871f-2469a88aaf91@o6g2000yqj.googlegroups.com>

On Jul 24, 4:10?am, Naoki INADA <songofaca... at gmail.com> wrote:
> > Yes! I confused by it.
>
> s/I confused/I am confused/
>
> > "Writing unicode to a file(-like)" is a simple requirement.
> > Does python have any simple resolution for it?
>
> s/resolution/solution/
>

Of course, Python 3 has much better Unicode support:
---------------------------------------------------------------------
C:\Users\Vinay>chcp 1251
Active code page: 1251

C:\Users\Vinay>\python31\python
ActivePython 3.1.0.1 (ActiveState Software Inc.) based on
Python 3.1 (r31:73572, Jun 28 2009, 19:55:39) [MSC v.1500 32 bit
(Intel)] on win
32
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.stdout.encoding
'cp1251'
>>> u = '\u0434\u043e \u0441\u0432\u0438\u0434\u0430\u043d\u0438\u044f'
>>> print(u)
?? ????????
>>> n = sys.stdout.write(u)
?? ????????>>> ^Z
---------------------------------------------------------------------

Regards,


Vinay Sajip


From piet at cs.uu.nl  Fri Jul 24 05:37:21 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 11:37:21 +0200
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>
Message-ID: <m2prbqifqm.fsf@cs.uu.nl>

>>>>> Naoki INADA <songofacandy at gmail.com> (NI) wrote:

>NI> "Writing unicode to a file(-like)" is a simple requirement.
>NI> Does python have any simple resolution for it?

Yes, Python 3 will do this. For Python < 3.0 you will have to use a
codecs wrapper or explicitely do the encoding.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From deets at nospam.web.de  Fri Jul 24 05:38:05 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 11:38:05 +0200
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
In-Reply-To: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
Message-ID: <7ctdo0F28litnU1@mid.uni-berlin.de>

Slaunger schrieb:
> OS: Win XP SP3, 32 bit
> Python 2.5.4
> 
> Hi I have run into some problems with allocating numpy.memmaps
> exceeding and accumulated size of about 2 GB. I have found out that
> the real problem relates to numpy.memmap using mmap.mmap
> 
> I've written a small test program to illustrate it:
> 
> import itertools
> import mmap
> import os
> 
> files = []
> mmaps = []
> file_names= []
> mmap_cap=0
> bytes_per_mmap = 100 * 1024 ** 2
> try:
>     for i in itertools.count(1):
>         file_name = "d:/%d.tst" % i
>         file_names.append(file_name)
>         f = open(file_name, "w+b")
>         files.append(f)
>         mm = mmap.mmap(f.fileno(), bytes_per_mmap)
>         mmaps.append(mm)
>         mmap_cap += bytes_per_mmap
>         print "Created %d writeable mmaps containing %d MB" % (i,
> mmap_cap/(1024**2))
> 
> #Clean up
> finally:
>     print "Removing mmaps..."
>     for mm, f, file_name in zip(mmaps, files, file_names):
>         mm.close()
>         f.close()
>         os.remove(file_name)
>     print "Done..."
> 
> 
> which creates this output
> 
> Created 1 writeable mmaps containing 100 MB
> Created 2 writeable mmaps containing 200 MB
> ....
> Created 17 writeable mmaps containing 1700 MB
> Created 18 writeable mmaps containing 1800 MB
> Removing mmaps...
> Done...
> Traceback (most recent call last):
>   File "C:\svn-sandbox\research\scipy\scipy\src\com\terma\kha
> \mmaptest.py", line 16, in <module>
>     mm = mmap.mmap(f.fileno(), bytes_per_mmap)
> WindowsError: [Error 8] Not enough storage is available to process
> this command
> 
> There is more than 25 GB of free space on drive d: at this stage.
> 
> Is it a bug or a "feature" of the 32 bit OS?

It's a limitation, yes. That's what 64-bit-OSes are for.

> I am surprised about it as I have not found any notes about these
> kinds of limitations in the documentation.
> 
> I am in dire need of these large memmaps for my task, and it is not an
> option to change OS due to other constraints in the system.
> 
> Is there anything I can do about it?

Only by partitioning data yourself, and accessing these partitions. Like 
in the good old days of DOS-programming.

Diez


From piet at cs.uu.nl  Fri Jul 24 05:38:51 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 11:38:51 +0200
Subject: effbot.org broken (WAS: Problems in commands.getoutput(cmd) with
	sox)
References: <mailman.3620.1248378772.8015.python-list@python.org>
Message-ID: <m2ljmeifo4.fsf@cs.uu.nl>

>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:

>CR> On Thu, Jul 23, 2009 at 12:42 PM, Chris Rebert<clp2 at rebertia.com> wrote:
>>> You can use tabnanny to help diagnose the problem:
>>> http://74.125.155.132/search?q=cache:QtxvZm3QDLsJ:effbot.org/librarybook/tabnanny.htm+tabnanny&cd=3&hl=en&ct=clnk&gl=us&client=firefox-a

>CR> Anyone know what's the deal with effbot.org? It seems to be broken at
>CR> present, forcing me to use Google's cached version.
>CR> It's a real shame since it has lots of handy Python info.

Just try again.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From __peter__ at web.de  Fri Jul 24 05:38:57 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 11:38:57 +0200
Subject: Adding method from one class to another class or to instance of
	another class
References: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
Message-ID: <h4bvf7$kj9$00$1@news.t-online.com>

marekw2143 wrote:

> Hi,
> 
> I have one class (A) that has defined method createVars. I would like
> to add that method to class B
> The code looks like this:
> 
> 
> class A(object):
>    def createVars(self):
>       self.v1 = 1
>       self.v2 = 3
>       pass
> 
> class B(object):
>    pass
> 
> 
> I don't want to use inheritance (because class A has many methods
> defined that class B doesn't need).

You can move createVars() into a mixin or common base class:

class M(object):
    def createVars(self): ...

class A(M):
    ...

class B(M)
    ...

> When I try the folloowing:
> 
> 
> B.createVars = C.createVars
> B().createVars()
> 
> 
> then the following error occurs:
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unbound method createVars() must be called with A instance
> as first argument (got nothing instead)
> 
> When I try to add the createVars method to instance of B:
> 
>>>> b=B()
>>>> b.createVars = new.instancemethod(A.createVars, b, B)
>>>> b.createVars
> <bound method B.createVars of <__main__.B object at 0x7f6330cc4a90>>
>>>> b.createVars()
> 
> 
> 
> Then the following error raises:
> 
> 
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unbound method createVars() must be called with A instance
> as first argument (got B instance instead)
> 
> 
> 
> How can I solve this problem?

>>> class A(object):
...     def create_vars(self):
...             self.x = 42
...
>>> class B(object): pass
...
>>> B.create_vars = A.create_vars.im_func
>>> b = B()
>>> b.create_vars()
>>> b.x
42

An alternative I find a bit cleaner:

>>> def create_vars(self): self.x = 42
...
>>> class A(object):
...     create_vars = create_vars
...
>>> class B(object):
...     create_vars = create_vars
...
>>> b = B()
>>> b.create_vars()
>>> b.x
42

Peter




From gagsl-py2 at yahoo.com.ar  Fri Jul 24 05:47:37 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 24 Jul 2009 06:47:37 -0300
Subject: available formats and params for Image.save()
References: <4a6833dd$0$22599$426a34cc@news.free.fr>
Message-ID: <op.uxkf5nv7x6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 06:56:45 -0300, News123 <news123 at free.fr> escribi?:

> Somehow I have difficulties reading the documentation for PIL (Image)
>
> Is there an easy way to know which formats are supported and what their
> names are?

py> import PIL
py> from PIL import Image
py> Image.ID
[]
py> Image.init()
py> Image.ID
['PNG', 'ARG', 'BMP', 'BUFR', 'CUR', 'PCX', 'DCX', 'EPS', 'FITS', 'FLI',  
'FPX',
'GBR', 'GIF', 'GRIB', 'HDF5', 'ICNS', 'ICO', 'IM', 'IMT', 'IPTC', 'JPEG',  
'MCIDA
S', 'TIFF', 'MIC', 'MPEG', 'MSP', 'PCD', 'PIXAR', 'PPM', 'PSD', 'SGI',  
'SPIDER',
  'SUN', 'TGA', 'WBMP', 'WMF', 'XBM', 'XPM', 'XVTHUMB']
py> Image.OPEN.keys()
['PCX', 'ICNS', 'HDF5', 'SUN', 'MIC', 'EPS', 'MSP', 'FLI', 'FITS', 'GBR',  
'WBMP'
, 'PCD', 'PIXAR', 'BUFR', 'PPM', 'WMF', 'SGI', 'BMP', 'TGA', 'DCX', 'ICO',  
'CUR'
, 'XPM', 'TIFF', 'JPEG', 'SPIDER', 'GIF', 'GRIB', 'IM', 'IMT', 'IPTC',  
'FPX', 'X
BM', 'MPEG', 'PSD', 'ARG', 'XVTHUMB', 'PNG', 'MCIDAS']
py> Image.SAVE.keys()
['XBM', 'PCX', 'SPIDER', 'HDF5', 'TIFF', 'BUFR', 'EPS', 'JPEG', 'MSP',  
'GRIB', '
GIF', 'BMP', 'IM', 'PPM', 'PDF', 'FITS', 'PALM', 'WBMP', 'WMF', 'PNG']

> Is there an easy way to know which parameters are supported by
> Image.save(). How can I list them where are they documented?

That depends on the format being used. The PIL handbook lists the standard  
formats used and their parameters:
http://www.pythonware.com/library/pil/handbook/index.htm

> I'm at a complete loss at finding out what parameters the save function
> accepts for saving a JPG file or a PNG file

http://www.pythonware.com/library/pil/handbook/format-jpeg.htm

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 24 06:06:29 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 24 Jul 2009 07:06:29 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3417.1248074972.8015.python-list@python.org>
	<EgE9m.507$646.499@nwrddc01.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
	<h4av5n$p1l$1@panix3.panix.com>
Message-ID: <op.uxkg03exx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 21:27:35 -0300, Aahz <aahz at pythoncraft.com> escribi?:
> In article <mailman.3561.1248307942.8015.python-list at python.org>,
> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>>
>> NLMPI
>
> What?

IHNFI

-- 
Gabriel Genellina



From amrita at iisermohali.ac.in  Fri Jul 24 06:20:11 2009
From: amrita at iisermohali.ac.in (amrita at iisermohali.ac.in)
Date: Fri, 24 Jul 2009 15:50:11 +0530 (IST)
Subject: how to get no value
Message-ID: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>


Hi,

I have a file having lines:-

48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
85 ALA H = 8.60 N =  CA =  HA = 4.65 C =

Now i want to make two another file in which i want to put those lines for
which C is missing and another one for which N,CA and C all are missing,

I tried in this way:
import re
f = open('chem.txt')
for line in f:
     if re.search('C = ',''):
        print line

but i am not getting the desired output.




Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA



From lpmelo at ualg.pt  Fri Jul 24 06:21:30 2009
From: lpmelo at ualg.pt (Luis Pedro Almeida)
Date: Fri, 24 Jul 2009 11:21:30 +0100
Subject: Convert points to polygon shapefile
Message-ID: <20090724101638.E93B414B2A@smtp3.ualg.pt>

Dear all,



I would like to know how to convert a list of points into a polygon 
shapefile (esri).



Thanks!



Best regards,



Luis Pedro Almeida



From gagsl-py2 at yahoo.com.ar  Fri Jul 24 06:24:52 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 24 Jul 2009 07:24:52 -0300
Subject: OverflowError in RLock.acquire()
References: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com>
Message-ID: <op.uxkhvqxgx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 24 Jul 2009 01:27:10 -0300, David Roberts <d at vidr.cc> escribi?:

> I'm trying to port a Python application to Windows, and I'm getting
> the following error (which did not occur when running on Linux):
>
> Exception in thread Thread-4:
>   File "C:\Python26\lib\threading.py", line 803, in currentThread
>     return _active[_get_ident()]
> OverflowError: can't convert negative value to unsigned long

Looks like a bug in the thread module - you should report it at  
http://bugs.python.org

-- 
Gabriel Genellina



From piet at cs.uu.nl  Fri Jul 24 06:46:14 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 12:46:14 +0200
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
Message-ID: <m2hbx2icjt.fsf@cs.uu.nl>

>>>>> Slaunger <Slaunger at gmail.com> (S) wrote:

>S> OS: Win XP SP3, 32 bit
>S> Python 2.5.4

>S> Hi I have run into some problems with allocating numpy.memmaps
>S> exceeding and accumulated size of about 2 GB. I have found out that
>S> the real problem relates to numpy.memmap using mmap.mmap

On Windows XP the virtual address space of a process is limited to 2 GB
unless the /3GB switch is used in the Boot.ini file.
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From darcy at druid.net  Fri Jul 24 06:56:03 2009
From: darcy at druid.net (D'Arcy J.M. Cain)
Date: Fri, 24 Jul 2009 06:56:03 -0400
Subject: how to get no value
In-Reply-To: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
References: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
Message-ID: <20090724065603.cd758a39.darcy@druid.net>

On Fri, 24 Jul 2009 15:50:11 +0530 (IST)
amrita at iisermohali.ac.in wrote:
> but i am not getting the desired output.

Show us what output you got and what you desired.

-- 
D'Arcy J.M. Cain <darcy at druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.


From deets at nospam.web.de  Fri Jul 24 06:56:16 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 12:56:16 +0200
Subject: how to get no value
In-Reply-To: <mailman.3649.1248430821.8015.python-list@python.org>
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <7ctiaiF1vrcvpU1@mid.uni-berlin.de>

amrita at iisermohali.ac.in schrieb:
> Hi,
> 
> I have a file having lines:-
> 
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
> 
> Now i want to make two another file in which i want to put those lines for
> which C is missing and another one for which N,CA and C all are missing,
> 
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
> 
> but i am not getting the desired output.


Gosh. Must be groundhog-day. Again.

And there is me thinking that my job could be endangered by cheap & 
qualified indian soft-workers - can't be to many of them around if the 
OP doesn't get a hold of one for the better part of a month now. Must be 
one of those management myths they tell you to scare you into a less 
well paid contract...

Diez


From beni.cherniavsky at gmail.com  Fri Jul 24 07:13:09 2009
From: beni.cherniavsky at gmail.com (Beni Cherniavsky)
Date: Fri, 24 Jul 2009 04:13:09 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com> 
	<mailman.3511.1248244497.8015.python-list@python.org>
Message-ID: <9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>

On Jul 22, 9:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>
> > My guess is that it was probably for optimization reasons long ago.
> > I've never heard a *good* reason why Python needs both.
>
> The good reason is the immutability, which lets you use
> a tuple as a dict key. ?
>
On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>
> > My guess is that it was probably for optimization reasons long ago.
> > I've never heard a *good* reason why Python needs both.
>
> The good reason is the immutability, which lets you use
> a tuple as a dict key.
>
The *technical* reason is immutability for dict keys.
Dict could allow mutable objects as keys by comparing *by value*,
making a copy on insertion and hashing the current value on lookup.
Prior art: the 2.3 sets module allows mutable Sets as elements in
Sets, by making ImmutableSet copies on insertion, and hashing Sets as
if they are temporarily immutable on lookup.

This inspired PEP 351 and ambitious proposals to expand the approach
to all Python with a copy-on-write scheme.  But these ideas were
rejected, and the 2.4 builtin sets only allow frozenset elements.
Half the reason is technical: copy-on-write and harder than it sounds,
and without it you pay a performance price.

But the deeper reason is style: immutable types are convenient!
The allow a pure-functional style of code, which can be simpler.
Of course, sometimes an imperative style is simpler.  Depends on the
problem.

My rule of thumb:
- Use mutable lists when you are likely to modify individual elements.
- Use immutable tuples when you are likely to replace the whole thing.

(In practice, this boils down to similar usage to the "official" rule
of thumb that lists are for homogenous data, and tuples for
heterogenous records.)


From d at vidr.cc  Fri Jul 24 07:29:44 2009
From: d at vidr.cc (David Roberts)
Date: Fri, 24 Jul 2009 21:29:44 +1000
Subject: OverflowError in RLock.acquire()
In-Reply-To: <op.uxkhvqxgx6zn5v@lepton.softlabbsas.com.ar>
References: <fe0877110907232127t5d596042qfb58b664d94ffefe@mail.gmail.com> 
	<op.uxkhvqxgx6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <fe0877110907240429w66aa63dhf40e887d23c373a9@mail.gmail.com>

Done: http://bugs.python.org/issue6562

--
David Roberts
http://da.vidr.cc/



On Fri, Jul 24, 2009 at 20:24, Gabriel Genellina<gagsl-py2 at yahoo.com.ar> wrote:
> En Fri, 24 Jul 2009 01:27:10 -0300, David Roberts <d at vidr.cc> escribi?:
>
>> I'm trying to port a Python application to Windows, and I'm getting
>> the following error (which did not occur when running on Linux):
>>
>> Exception in thread Thread-4:
>> ?File "C:\Python26\lib\threading.py", line 803, in currentThread
>> ? ?return _active[_get_ident()]
>> OverflowError: can't convert negative value to unsigned long
>
> Looks like a bug in the thread module - you should report it at
> http://bugs.python.org
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From piet at cs.uu.nl  Fri Jul 24 07:48:09 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 13:48:09 +0200
Subject: how to get no value
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <m2d47qi9om.fsf@cs.uu.nl>

>>>>> amrita at iisermohali.ac.in (a) a ?crit:

>a> Hi,

>a> I have a file having lines:-

>a> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
>a> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
>a> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =

>a> Now i want to make two another file in which i want to put those lines for
>a> which C is missing and another one for which N,CA and C all are missing,

>a> I tried in this way:
>a> import re
>a> f = open('chem.txt')
>a> for line in f:
>a>      if re.search('C = ',''):
>a>         print line

>a> but i am not getting the desired output.

You never look in the lines you read. 
    if re.search('C = ',''): should be
    if re.search('C = ', line):

Do you really think before you write your code? Or look at it after you
have written it? 

Sorry if I offend you but you give the impression of just trying some
more or less random stuff and then asking here if it doesn't give the
required result.

That's not the attitude of a researcher, unless your definition of
research is 'asking on Usenet'.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From pdpinheiro at gmail.com  Fri Jul 24 08:08:21 2009
From: pdpinheiro at gmail.com (pdpi)
Date: Fri, 24 Jul 2009 05:08:21 -0700 (PDT)
Subject: Convert points to polygon shapefile
References: <mailman.3651.1248432554.8015.python-list@python.org>
Message-ID: <dd1e7139-0011-4e7c-8d9e-6471d8348564@o32g2000yqm.googlegroups.com>

On Jul 24, 11:21?am, Luis Pedro Almeida <lpm... at ualg.pt> wrote:
> Dear all,
>
> I would like to know how to convert a list of points into a polygon
> shapefile (esri).
>
> Thanks!
>
> Best regards,
>
> Luis Pedro Almeida

I think you'd be better served by asking this question in a newsgroup
dedicated to GIS software (I'm guessing that's the ESRI you meant).
Still, what you want is to find the file format specification, and
implement it.


From piet at cs.uu.nl  Fri Jul 24 08:14:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 14:14:27 +0200
Subject: Convert points to polygon shapefile
References: <mailman.3651.1248432554.8015.python-list@python.org>
Message-ID: <m28wiei8gs.fsf@cs.uu.nl>

>>>>> Luis Pedro Almeida <lpmelo at ualg.pt> (LPA) wrote:

>LPA> Dear all,
>LPA> I would like to know how to convert a list of points into a
>LPA> polygon shapefile (esri).

http://lmgtfy.com/?q=esri+shapefile+Python
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From davea at ieee.org  Fri Jul 24 08:25:17 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 24 Jul 2009 08:25:17 -0400
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
In-Reply-To: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
Message-ID: <4A69A82D.8090301@ieee.org>

Slaunger wrote:
> OS: Win XP SP3, 32 bit
> Python 2.5.4
>
> Hi I have run into some problems with allocating numpy.memmaps
> exceeding and accumulated size of about 2 GB. I have found out that
> the real problem relates to numpy.memmap using mmap.mmap
>
> I've written a small test program to illustrate it:
>
> import itertools
> import mmap
> import os
>
> files = []
> mmaps = []
> file_names= []
> mmap_cap=0
> bytes_per_mmap = 100 * 1024 ** 2
> try:
>     for i in itertools.count(1):
>         file_name = "d:/%d.tst" % i
>         file_names.append(file_name)
>         f = open(file_name, "w+b")
>         files.append(f)
>         mm = mmap.mmap(f.fileno(), bytes_per_mmap)
>         mmaps.append(mm)
>         mmap_cap += bytes_per_mmap
>         print "Created %d writeable mmaps containing %d MB" % (i,
> mmap_cap/(1024**2))
>
> #Clean up
> finally:
>     print "Removing mmaps..."
>     for mm, f, file_name in zip(mmaps, files, file_names):
>         mm.close()
>         f.close()
>         os.remove(file_name)
>     print "Done..."
>
>
> which creates this output
>
> Created 1 writeable mmaps containing 100 MB
> Created 2 writeable mmaps containing 200 MB
> ....
> Created 17 writeable mmaps containing 1700 MB
> Created 18 writeable mmaps containing 1800 MB
> Removing mmaps...
> Done...
> Traceback (most recent call last):
>   File "C:\svn-sandbox\research\scipy\scipy\src\com\terma\kha
> \mmaptest.py", line 16, in <module>
>     mm = mmap.mmap(f.fileno(), bytes_per_mmap)
> WindowsError: [Error 8] Not enough storage is available to process
> this command
>
> There is more than 25 GB of free space on drive d: at this stage.
>
> Is it a bug or a "feature" of the 32 bit OS?
>
> I am surprised about it as I have not found any notes about these
> kinds of limitations in the documentation.
>
> I am in dire need of these large memmaps for my task, and it is not an
> option to change OS due to other constraints in the system.
>
> Is there anything I can do about it?
>
> Best wishes,
> Kim
>
>   
It's not a question of how much disk space there is, but how much 
virtual space 32 bits can address.  2**32 is about 4 gig, and Windows XP 
reserves about half of that for system use.  Presumably a 64 bit OS 
would have a much larger limit.

Years ago I worked on Sun Sparc system which had much more limited 
shared memory access, due to hardware limitations.  So 2gig seems pretty 
good to me.

There is supposed to be a way to tell the Windows OS to only use 1 gb of 
virtual space, leaving 3gb for application use.  But there are some 
limitations, and I don't recall what they are.  I believe it has to be 
done globally (probably in Boot.ini), rather than per process.  And some 
things didn't work in that configuration.

DaveA



From jeanmichel at sequans.com  Fri Jul 24 08:34:23 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 24 Jul 2009 14:34:23 +0200
Subject: doted filenames in import statements
In-Reply-To: <h47fko$tqp$1@ger.gmane.org>
References: <mailman.3488.1248212574.8015.python-list@python.org>	<m2prbtllen.fsf@cs.uu.nl>	<4A670313.8040204@sequans.com>
	<h47fko$tqp$1@ger.gmane.org>
Message-ID: <4A69AA4F.9060707@sequans.com>

Terry Reedy wrote:
> Jean-Michel Pichavant wrote:
>> Piet van Oostrum wrote:
>>>
>>> [snip]
>>>
>>>> JP> file = "/home/dsp/4.6.0.0/test.py"
>>>> JP> test = __import__(file)
>>>> JP> => no module name blalalal found.
>>>
>>>
>>>> JP> Any suggestion ? I tried multiple escape technics without any 
>>>> success.
>>>
>>> Rightly so.
>>>
>>> I think the best would be to add the directory to sys.path 
>>> sys.path.add('/home/dsp/4.6.0.0')
>>> and then
>>> __import__('test', ... ) 
>>
>> I see. My problem is that a have to import 2 different files having 
>> de same name. In the same name space I have 2 objects from 2 
>> different software branches, let's say 4.6.0 and 4.6.1.
>> The first object shall import 4.6.0/orb.py and the second one 
>> 4.6.1/orb.py.
>>
>> If I add 4.6.1 to sys.path, the import statement will look like:
>> self._orb = __import__('orb')
>> The problem is, python wil assume orb is already imported and will 
>> assign the module from the 4.6.0 branch to my 4.6.1 object.
>>
>> Do I have to mess up with sys.modules keys to make python import the 
>> correct file ? Is there a standard/proper way to do that ?
>
> If you make the directory names into proper identifiers like v460 and 
> v461 and add __init__.py to each to make them packages and have both 
> on search path, then
>
> import v460.orb #or import v460.orb as orb460
> import v461.orb #or import v460.orb as orb461
>
> will get you both. One way or another, they have to get different 
> names within Python.
>
> Terry Jan Reedy
>

I finally had to write my own import statement as I prefered to 
manipulate the python objects instead of manipulating third party files. 
Basically when importing 'file.py' it records it in sys.modules as 
sys.modules['__magic_word_file''] and then I remove the standard 
reference. This allows me to import file.py again, but with a totally 
different path. (path is temporarily added to sys.path)

JM


From sanne at kortec.nl  Fri Jul 24 08:34:53 2009
From: sanne at kortec.nl (Sanne Korzec)
Date: Fri, 24 Jul 2009 14:34:53 +0200
Subject: trouble with wrapping a c program
Message-ID: <20090724123458.TOWM14607.viefep17-int.chello.at@edge02.upc.biz>

Hi Mailing,

 

I am using a c program, which first initializes for some seconds and then
waits for user input (keyboard) to type something. When enter is pressed the
c program continues. 

 

I have wrapped this program in a python script, which starts the c program.
To start the c program, there are many options in python e.g.

 

Os.system os.popen or subprocess.popen 

To me there does not seem to be a difference for starting the program. They
all work well.

 

However the problem occurs when I want to input data during this c program. 

 

Using the keyboard and then enter in the c program prompt works, but I wish
to do this from the python script by sending the string from the python
script.

 

I am able to print the string from python with a print command or with a
stdout.write command. But this simply prints it to the prompt, the c program
does nothing with this printed string.

 

Is there a way to pipe, stream, or send this string to the running c
program?

 

All tutorials about piping I have read, seem to have to wait for the process
to finish. Or need the stdin string before starting the program.

Note that the c program is not finished when the input is needed, so I
cannot use subprocess.call or wait.

It is possible to give the user input in advance, but I do not want this,
because this makes everything much slower!

I really would like to do this during/while the c program is running.

 

I have created a thread and a small xmlrpc server for this and this works
fine. However I cannot seem to pass the string.

 

Here is a small fragment of my code:

 

#initialization

cmd = [a list of my program and arguments]

subprocess.Popen(cmd)   #starts the c program

 

 

#somewhere along the way

Send_string(str):

            

#Sys.stdin = str

            #subprocess.stdin = str

 

 

I have spent the entire night trying to get this to work, but I can't seem
to get it right. Any help is much appreciated. Also, if anybody could
explain me where the fuck-up in my brain is, I would be very happy..

 

Sanne              

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090724/46e39bd6/attachment-0001.html>

From doetoe at gmail.com  Fri Jul 24 08:38:00 2009
From: doetoe at gmail.com (Utpal Sarkar)
Date: Fri, 24 Jul 2009 05:38:00 -0700 (PDT)
Subject: non-owning references?
Message-ID: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>

Hi,

I'm not sure the subject describes what I'm looking for, but the
question is the following:
Is there a way I can tell a variable that the object it is pointing
too is not owned by it, in the sense that if it is the only reference
to the object it can be garbage collected?
I want this for what is essentially a singleton class, so that on
first instantiation the object is created and a reference is kept in
the class, that is used to return the same object in subsequent
instantiations. When all instances go out of scope, the reference in
the class is still there, preventing it from being garbage collected,
but since the instance can be huge, I would like it to be.

Thanks,

Utpal


From __peter__ at web.de  Fri Jul 24 08:52:07 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 24 Jul 2009 14:52:07 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
Message-ID: <h4capd$sn3$01$1@news.t-online.com>

Utpal Sarkar wrote:

> Is there a way I can tell a variable that the object it is pointing
> too is not owned by it, in the sense that if it is the only reference
> to the object it can be garbage collected?

http://docs.python.org/library/weakref.html




From gh at ghaering.de  Fri Jul 24 09:00:43 2009
From: gh at ghaering.de (=?ISO-8859-1?Q?Gerhard_H=E4ring?=)
Date: Fri, 24 Jul 2009 15:00:43 +0200
Subject: non-owning references?
In-Reply-To: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
Message-ID: <h4cb9r$b52$1@ger.gmane.org>

Utpal Sarkar wrote:
> Hi,
> [...]

You're looking for the weakref module.

What you're describing there sounds like a nice exercise, but I cannot
imagine why you'd really need to clean it up, if it really is a singleton.

-- Gerhard



From ben+python at benfinney.id.au  Fri Jul 24 09:06:34 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 24 Jul 2009 23:06:34 +1000
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
Message-ID: <87d47q5ixx.fsf@benfinney.id.au>

Utpal Sarkar <doetoe at gmail.com> writes:

> Is there a way I can tell a variable that the object it is pointing
> too is not owned by it, in the sense that if it is the only reference
> to the object it can be garbage collected?

Python doesn't have ?pointers?, and doesn't really have ?variables?
either, at least not how many other languages use that term.

What it does have is references to objects
<URL:http://effbot.org/zone/python-objects.htm>.

> on first instantiation the object is created and a reference is kept
> in the class, that is used to return the same object in subsequent
> instantiations. When all instances go out of scope, the reference in
> the class is still there, preventing it from being garbage collected,
> but since the instance can be huge, I would like it to be.

What you are asking for is called a ?weak reference? and is provided
by the ?weakref? module <URL:http://docs.python.org/library/weakref>.

-- 
 \      ?Patience, n. A minor form of despair, disguised as a virtue.? |
  `\                   ?Ambrose Bierce, _The Devil's Dictionary_, 1906 |
_o__)                                                                  |
Ben Finney


From doetoex at gmail.com  Fri Jul 24 09:18:48 2009
From: doetoex at gmail.com (Doetoe)
Date: Fri, 24 Jul 2009 06:18:48 -0700 (PDT)
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
Message-ID: <14f1729b-9035-417f-a725-3deaa9408a69@c2g2000yqi.googlegroups.com>

On Jul 24, 3:06?pm, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Utpal Sarkar <doe... at gmail.com> writes:
> > Is there a way I can tell a variable that the object it is pointing
> > too is not owned by it, in the sense that if it is the only reference
> > to the object it can be garbage collected?
>
> Python doesn't have ?pointers?, and doesn't really have ?variables?
> either, at least not how many other languages use that term.
>
> What it does have is references to objects
> <URL:http://effbot.org/zone/python-objects.htm>.
>
> > on first instantiation the object is created and a reference is kept
> > in the class, that is used to return the same object in subsequent
> > instantiations. When all instances go out of scope, the reference in
> > the class is still there, preventing it from being garbage collected,
> > but since the instance can be huge, I would like it to be.
>
> What you are asking for is called a ?weak reference? and is provided
> by the ?weakref? module <URL:http://docs.python.org/library/weakref>.
>
> --
> ?\ ? ? ??Patience, n. A minor form of despair, disguised as a virtue.? |
> ? `\ ? ? ? ? ? ? ? ? ? ?Ambrose Bierce, _The Devil's Dictionary_, 1906 |
> _o__) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?|
> Ben Finney

Thanks to the three of you. This is precisely what I needed!
Gerhard, the reason I need to clean it up is that it is a lazy data
structure that can grow to arbitrary size. When it is not needed
anymore it would still remain in memory.

Utpal


From breamoreboy at yahoo.co.uk  Fri Jul 24 09:50:33 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 24 Jul 2009 14:50:33 +0100
Subject: how to get no value
In-Reply-To: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
References: <23321.210.212.36.65.1248430811.squirrel@www.iisermohali.ac.in>
Message-ID: <h4ce4v$kfe$1@ger.gmane.org>

amrita at iisermohali.ac.in wrote:
> Hi,
> 
> I have a file having lines:-
> 
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
> 
> Now i want to make two another file in which i want to put those lines for
> which C is missing and another one for which N,CA and C all are missing,
> 
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
> 
> but i am not getting the desired output.
> 
> 
> 
> 
> Amrita Kumari
> Research Fellow
> IISER Mohali
> Chandigarh
> INDIA
> 
Try writing correct rather than incorrect code.  Or as has been 
repeatedly stated get somone from your CS department to help.


-- 

Kindest regards.

Mark Lawrence.



From hniksic at xemacs.org  Fri Jul 24 09:55:45 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Fri, 24 Jul 2009 15:55:45 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
Message-ID: <87fxcm5gny.fsf@busola.homelinux.net>

Ben Finney <ben+python at benfinney.id.au> writes:

> Utpal Sarkar <doetoe at gmail.com> writes:
>
>> Is there a way I can tell a variable that the object it is pointing
>> too is not owned by it, in the sense that if it is the only reference
>> to the object it can be garbage collected?
>
> Python doesn't have ?pointers?, and doesn't really have ?variables?
> either, at least not how many other languages use that term.

The OP didn't use the term "pointer", but the word "pointing", which
makes sense in the context.  The term "variable" is used in the Python
language reference and elsewhere, and is quite compatible with how other
popular languages (Java, PHP, Lisp, ...) use it.  Please stop
complaining about valid terminology; it is not helpful.


From invalid at invalid  Fri Jul 24 09:57:02 2009
From: invalid at invalid (Grant Edwards)
Date: Fri, 24 Jul 2009 08:57:02 -0500
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>

On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>
> Some aspects of the Python design are remarkably clever, while
> others leave me perplexed. Here's an example of the latter:
> Why does len() give an error when applied to an int or float?
> len() should always return something; in particular, when
> applied to a scalar, it should return a value of 1.

If len(7) returned a value of 1, then wouldn't one expect 7[0]
to be valid?  It isn't, so you'd then have to redefine all
types so that they are sequences that can be indexed.  Sounds
like a big mess to me...

[Are there types for which len() returns a value that can't be
indexed?]

-- 
Grant Edwards                   grante             Yow! It's the RINSE CYCLE!!
                                  at               They've ALL IGNORED the
                               visi.com            RINSE CYCLE!!


From timlee126 at yahoo.com  Fri Jul 24 10:03:22 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 24 Jul 2009 07:03:22 -0700 (PDT)
Subject: Popen
Message-ID: <896055.35192.qm@web63101.mail.re1.yahoo.com>


Hi,
I wonder if I use Popen, the parent process will wait for the child process to finish or continue without waiting?
Thanks and regards!


      


From invalid at invalid  Fri Jul 24 10:10:29 2009
From: invalid at invalid (Grant Edwards)
Date: Fri, 24 Jul 2009 09:10:29 -0500
Subject: how to get no value
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <MOKdne1B6L9IXfTXnZ2dnUVZ_qqdnZ2d@posted.visi>

On 2009-07-24, amrita at iisermohali.ac.in <amrita at iisermohali.ac.in> wrote:
>
> Hi,
>
> I have a file having lines:-
>
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
>
> Now i want to make two another file in which i want to put
> those lines for which C is missing and another one for which
> N,CA and C all are missing,
>
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
>
> but i am not getting the desired output.

I've told you before: don't use regular expressions (e.g. the
"re" module).  Stop using regular expressions now.  Regular
expressions are way beyond your capabilities.  

Use simple operations like split() and "in":

  f = open('chem.txt')
  for line in f:
    if "C = " in line:
      print line
      
You really need to work through a Python tutorial or two:

  http://docs.python.org/tutorial/
  http://www.greenteapress.com/thinkpython/thinkpython.html

Better yet, take an couple introductory programming courses.

I'm a bit surprised that one could become a "Research Fellow"
in a scientific field without taking any programming courses.

-- 
Grant Edwards                   grante             Yow! I'm also against
                                  at               BODY-SURFING!!
                               visi.com            


From rhodri at wildebst.demon.co.uk  Fri Jul 24 10:11:40 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 15:11:40 +0100
Subject: len() should always return something
In-Reply-To: <4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
Message-ID: <op.uxksdqn1a8ncjz@gnudebst>

On Fri, 24 Jul 2009 14:57:02 +0100, Grant Edwards <invalid at invalid> wrote:

> On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>>
>> Some aspects of the Python design are remarkably clever, while
>> others leave me perplexed. Here's an example of the latter:
>> Why does len() give an error when applied to an int or float?
>> len() should always return something; in particular, when
>> applied to a scalar, it should return a value of 1.
>
> If len(7) returned a value of 1, then wouldn't one expect 7[0]
> to be valid?  It isn't, so you'd then have to redefine all
> types so that they are sequences that can be indexed.  Sounds
> like a big mess to me...
>
> [Are there types for which len() returns a value that can't be
> indexed?]
>

Dictionaries.

Which doesn't make your point less valid.  In fact I'd go so
far as to argue that what len() gives you is the number of
items in a container, so len(7) should return 0.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From rhodri at wildebst.demon.co.uk  Fri Jul 24 10:21:36 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 15:21:36 +0100
Subject: non-owning references?
In-Reply-To: <87fxcm5gny.fsf@busola.homelinux.net>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
Message-ID: <op.uxksuaifa8ncjz@gnudebst>

On Fri, 24 Jul 2009 14:55:45 +0100, Hrvoje Niksic <hniksic at xemacs.org>  
wrote:

> Ben Finney <ben+python at benfinney.id.au> writes:
>
>> Utpal Sarkar <doetoe at gmail.com> writes:
>>
>>> Is there a way I can tell a variable that the object it is pointing
>>> too is not owned by it, in the sense that if it is the only reference
>>> to the object it can be garbage collected?
>>
>> Python doesn't have ?pointers?, and doesn't really have ?variables?
>> either, at least not how many other languages use that term.
>
> The OP didn't use the term "pointer", but the word "pointing", which
> makes sense in the context.  The term "variable" is used in the Python
> language reference and elsewhere, and is quite compatible with how other
> popular languages (Java, PHP, Lisp, ...) use it.

Only superficially.  Treating Python variables the same as C variables
(say) is one of the classic ways that newbies come unstuck when mutable
objects appear on the scene.  While the OP appears to have the right idea,
your "correction" here could be quite misleading.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From pruebauno at latinmail.com  Fri Jul 24 10:45:21 2009
From: pruebauno at latinmail.com (nn)
Date: Fri, 24 Jul 2009 07:45:21 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3636.1248390216.8015.python-list@python.org>
Message-ID: <c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>

On Jul 23, 7:03?pm, Dave Angel <da... at ieee.org> wrote:
> Mark Tarver wrote:
> > I have a very strange error. ?I have two test python files test.py and
> > python.py which contain the following code
>
> > #!/usr/bin/python
> > print "Content-type: text/html"
> > print
> > print "<html>"
> > print "<center>Hello, Linux.com!</center>"
> > print "</html>"
>
> > One file (test.py) works; you call it up and it shows a web page with
>
> > Hello, Linux.com
>
> > The other fails with a server configuration error. ?Both are running
> > under Linux, same server, same permissions. ?Running a character scan
> > shows that both files contain the same printable characters and are
> > therefore typographically identical. ? They are absolutely the same.
>
> > The only hint at a difference I can see is that my ftp program says
> > the files are of unequal lengths. ?test.py is 129 bytes long.
> > python.py 134 bytes long.
>
> > A zipped folder containing both files is at
>
> >www.lambdassociates.org/weird.zip
>
> > Any ideas welcome.
>
> > Mark
>
> Easiest explanation is that python.py has Windows-style newlines. ?In
> other words, each line ends with 0d0a, rather than the Unix convention
> of 0a.
>
> If your server is Unix-based, it can't handle that first line, since it
> has an illegal character (0d) following the
>
> #!/usr/bin/python
>
> line. ?Convert it to Unix line-endings.
>
> DaveA

Use dos2unix for conversion of the longer file and try again:

http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm


From dickinsm at gmail.com  Fri Jul 24 10:45:40 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Fri, 24 Jul 2009 07:45:40 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org> 
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
Message-ID: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>

On Jul 24, 3:11?pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
wrote:
> Which doesn't make your point less valid. ?In fact I'd go so
> far as to argue that what len() gives you is the number of
> items in a container, so len(7) should return 0.

Nah.  7 contains three bits, so len(7) should *clearly* return 3.

Mark


From user at example.net  Fri Jul 24 10:50:03 2009
From: user at example.net (superpollo)
Date: Fri, 24 Jul 2009 16:50:03 +0200
Subject: len() should always return something
In-Reply-To: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
Message-ID: <4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>

Mark Dickinson wrote:
> On Jul 24, 3:11 pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
> wrote:
> 
>>Which doesn't make your point less valid.  In fact I'd go so
>>far as to argue that what len() gives you is the number of
>>items in a container, so len(7) should return 0.
> 
> 
> Nah.  7 contains three bits, so len(7) should *clearly* return 3.

and len("7") must return 8, by the same token... but wait!

 >>> len("7")
1
 >>>

my python installation must me outdated ;-)

bye



From deets at nospam.web.de  Fri Jul 24 10:51:12 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 16:51:12 +0200
Subject: len() should always return something
In-Reply-To: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
Message-ID: <7cu030F295totU1@mid.uni-berlin.de>

Mark Dickinson schrieb:
> On Jul 24, 3:11 pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
> wrote:
>> Which doesn't make your point less valid.  In fact I'd go so
>> far as to argue that what len() gives you is the number of
>> items in a container, so len(7) should return 0.
> 
> Nah.  7 contains three bits, so len(7) should *clearly* return 3.

But it contains a minimum of 32 bits! And why are you treating ones as 
special over zeros? I thought the times of BitRacism were finally over...

Diez


From kushal.kumaran+python at gmail.com  Fri Jul 24 10:58:49 2009
From: kushal.kumaran+python at gmail.com (Kushal Kumaran)
Date: Fri, 24 Jul 2009 20:28:49 +0530
Subject: Popen
In-Reply-To: <896055.35192.qm@web63101.mail.re1.yahoo.com>
References: <896055.35192.qm@web63101.mail.re1.yahoo.com>
Message-ID: <1e364c4e0907240758k753f8653o225ac97e92fd2eea@mail.gmail.com>

On Fri, Jul 24, 2009 at 7:33 PM, Tim<timlee126 at yahoo.com> wrote:
>
> Hi,
> I wonder if I use Popen, the parent process will wait for the child process to finish or continue without waiting?
> Thanks and regards!
>

Assuming you mean subprocess.Popen, the child is executed
asynchronously.  You can use the wait() method on the Popen object if
you want the parent to wait for the child to finish.

-- 
kushal


From piet at cs.uu.nl  Fri Jul 24 11:03:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:03:58 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<mailman.3662.1248445305.8015.python-list@python.org>
Message-ID: <m23a8mi0m9.fsf@cs.uu.nl>

>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:

>RJ> On Fri, 24 Jul 2009 14:55:45 +0100, Hrvoje Niksic <hniksic at xemacs.org>  wrote:
>>> Ben Finney <ben+python at benfinney.id.au> writes:
>>> 
>>>> Utpal Sarkar <doetoe at gmail.com> writes:
>>>> 
>>>>> Is there a way I can tell a variable that the object it is pointing
>>>>> too is not owned by it, in the sense that if it is the only reference
>>>>> to the object it can be garbage collected?
>>>> 
>>>> Python doesn't have ?pointers?, and doesn't really have ?variables?
>>>> either, at least not how many other languages use that term.
>>> 
>>> The OP didn't use the term "pointer", but the word "pointing", which
>>> makes sense in the context.  The term "variable" is used in the Python
>>> language reference and elsewhere, and is quite compatible with how other
>>> popular languages (Java, PHP, Lisp, ...) use it.

>RJ> Only superficially.  Treating Python variables the same as C variables
>RJ> (say) is one of the classic ways that newbies come unstuck when mutable
>RJ> objects appear on the scene.  While the OP appears to have the right idea,
>RJ> your "correction" here could be quite misleading.

If you read the OP, it is clear that he talked about a class variable,
which is a perfectly legal notion in Python, and is mentioned as such in
the language reference manual:
`Variables defined in the class definition are class variables'

And who was talking about C variables?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Fri Jul 24 11:06:23 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:06:23 +0200
Subject: how to get no value
References: <mailman.3649.1248430821.8015.python-list@python.org>
Message-ID: <m2vdliglxs.fsf@cs.uu.nl>

Well actually your subject is `how to get no value'. Your code does that
perfectly. :=)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From inky788 at gmail.com  Fri Jul 24 11:07:30 2009
From: inky788 at gmail.com (Inky 788)
Date: Fri, 24 Jul 2009 08:07:30 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<mailman.3511.1248244497.8015.python-list@python.org>
	<1b78798e-9d5b-4037-91f1-5fad600514f0@d32g2000yqh.googlegroups.com>
	<mailman.3570.1248335976.8015.python-list@python.org>
Message-ID: <f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>

On Jul 23, 3:42?am, Hendrik van Rooyen <hend... at microcorp.co.za>
wrote:
> On Wednesday 22 July 2009 16:36:51 Inky 788 wrote:
>
> > On Jul 22, 2:36?am, Hendrik van Rooyen <hend... at microcorp.co.za>
>
> > wrote:
> > > The good reason is the immutability, which lets you use
> > > a tuple as a dict key. ?
>
> > Thanks for the reply Hendrik (and Steven (other reply)). Perhaps I'm
> > just not sophisticated enough, but I've never wanted to use a list/
> > tuple as a dict key. This sounds like obscure usage, and a bit
> > contrived as a reason for having *both* lists and tuples.
>
> Steven showed why you cannot have a mutable thing
> as a key in a dict.
>
> if you think it is contrived, then please consider how you would
> keep track of say the colour of a pixel on a screen at position
> (x,y) - this is about the simplest "natural" tuple format and
> example.

My guess is that this is probably the way most people do it:

~~~~
#!/usr/bin/env python

import sys
import random

if len( sys.argv ) != 3:
    print "Please pass exactly 2 ints. Exiting."
    sys.exit(1)

NUM_COLUMNS = int( sys.argv[1] )
NUM_ROWS    = int( sys.argv[2] )

print "Making array of %s columns by %s rows." % (NUM_COLUMNS,
NUM_ROWS)

def rand():
    return int( 255 * random.random())

def make_a_pixel():
    #       red     green   blue
    return [rand(), rand(), rand()]

def make_a_row(num_columns):
    temp_row = []
    for i in range(num_columns):
        temp_row.append( make_a_pixel() )
    return temp_row

def make_array_of_pixels(num_columns, num_rows):
    rows = []
    for i in range(num_rows):
        rows.append( make_a_row(num_columns) )
    return rows

def show_pixels(pixel_array):
    for row in pixel_array:
        for pixel in row:
            print pixel, '  ',
        print


rows_of_pixels = make_array_of_pixels(NUM_COLUMNS, NUM_ROWS)

show_pixels(rows_of_pixels)
~~~~


From piet at cs.uu.nl  Fri Jul 24 11:10:07 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:10:07 +0200
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
Message-ID: <m2r5w6glrk.fsf@cs.uu.nl>

>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:

>RJ> On Fri, 24 Jul 2009 14:57:02 +0100, Grant Edwards <invalid at invalid> wrote:
>>> On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>>>> 
>>>> Some aspects of the Python design are remarkably clever, while
>>>> others leave me perplexed. Here's an example of the latter:
>>>> Why does len() give an error when applied to an int or float?
>>>> len() should always return something; in particular, when
>>>> applied to a scalar, it should return a value of 1.
>>> 
>>> If len(7) returned a value of 1, then wouldn't one expect 7[0]
>>> to be valid?  It isn't, so you'd then have to redefine all
>>> types so that they are sequences that can be indexed.  Sounds
>>> like a big mess to me...
>>> 
>>> [Are there types for which len() returns a value that can't be
>>> indexed?]
>>> 

>RJ> Dictionaries.

>RJ> Which doesn't make your point less valid.  In fact I'd go so
>RJ> far as to argue that what len() gives you is the number of
>RJ> items in a container, so len(7) should return 0.

But len(7) could as well be defined as 3, 1, 32, or 64 (depending on the
implementation). Therefore it doesn't make much sense.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From ben+python at benfinney.id.au  Fri Jul 24 11:14:06 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 25 Jul 2009 01:14:06 +1000
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
Message-ID: <8763di5d1d.fsf@benfinney.id.au>

Hrvoje Niksic <hniksic at xemacs.org> writes:

> The term "variable" is used in the Python language reference and
> elsewhere

Yes. It should also be abundantly clear from the constant stream of
confused newbies on this point that its usage of that term is different
to what many expect from usage elsewhere.

> and is quite compatible with how other popular languages (Java, PHP,
> Lisp, ...) use it. Please stop complaining about valid terminology; it
> is not helpful.

I disagree with your assertions.

Rather than yet another round of this tedious debate, I merely point
interested readers to <URL:http://effbot.org/zone/python-objects.htm>
and ask them to draw their own conclusion on how compatible their
pre-existing ?variable? concept is with Python's object reference
model.

-- 
 \     ?Too many pieces of music finish too long after the end.? ?Igor |
  `\                                                       Stravinskey |
_o__)                                                                  |
Ben Finney


From piet at cs.uu.nl  Fri Jul 24 11:17:56 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 17:17:56 +0200
Subject: Popen
References: <mailman.3660.1248444211.8015.python-list@python.org>
Message-ID: <m2my6uglej.fsf@cs.uu.nl>

>>>>> Tim <timlee126 at yahoo.com> (T) wrote:

>T> Hi,
>T> I wonder if I use Popen, the parent process will wait for the child process to finish or continue without waiting?
>T> Thanks and regards!

Only if you use Popen.wait(),  Popen.communicate() or something similar
like os.waitpid(), subprocess.call()
      

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From rylesny at gmail.com  Fri Jul 24 11:22:55 2009
From: rylesny at gmail.com (ryles)
Date: Fri, 24 Jul 2009 08:22:55 -0700 (PDT)
Subject: difference in printing to screen Mac / Windows
References: <6946b9500907180321j1ee7b254ua00d520599745ec1@mail.gmail.com> 
	<mailman.3354.1247914997.8015.python-list@python.org>
Message-ID: <eeccc6b5-f4aa-49b9-93e6-803a6c77c8ab@d4g2000vbm.googlegroups.com>

On Jul 18, 7:03?am, Tim Chase <python.l... at tim.thechases.com> wrote:
> Lastly, you can force all standard-output in your program to be
> unbuffered without the "-u" parameter:

And if you're using -u a lot, the PYTHONUNBUFFERED environment
variable can also be set (but not empty), so that python adds the
option automatically.


From Scott.Daniels at Acm.Org  Fri Jul 24 11:54:32 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 24 Jul 2009 08:54:32 -0700
Subject: regex: multiple matching for one string
In-Reply-To: <e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com>
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
	<zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com>
	<e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com>
Message-ID: <o7Kdncbpm-78SvTXnZ2dnUVZ_vmdnZ2d@pdx.net>

rurpy at yahoo.com wrote:
> Nick Dumas wrote:
>> On 7/23/2009 9:23 AM, Mark Lawrence wrote:
>>> scriptlearner at gmail.com wrote:
>>>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>>>> will like to take out the values (valuea, valueb, and valuec).  How do
>>>> I do that in Python?  The group method will only return the matched
>>>> part.  Thanks.
>>>>
>>>> p = re.compile('#a=*;b=*;c=*;')
>>>> m = p.match(line)
>>>>         if m:
>>>>              print m.group(),
>>> IMHO a regex for this is overkill, a combination of string methods such
>>> as split and find should suffice.
> 
> You're saying that something like the following
> is better than the simple regex used by the OP?
> [untested]
> values = []
> parts = line.split(';')
> if len(parts) != 4: raise SomeError()
> for p, expected in zip (parts[-1], ('#a','b','c')):
>     name, x, value = p.partition ('=')
>     if name != expected or x != '=':
>         raise SomeError()
>     values.append (value)
> print values[0], values[1], values[2]
I call straw man: [tested]
     line = "#a=valuea;b=valueb;c=valuec;"
     d = dict(single.split('=', 1)
              for single in line.split(';') if single)
     d['#a'], d['b'], d['c']
If you want checking code, add:
     if len(d) != 3:
         raise ValueError('Too many keys: %s in %r)' % (
                              sorted(d), line))

> Blech, not in my book.  The regex checks the
> format of the string, extracts the values, and
> does so very clearly.  Further, it is easily
> adapted to other similar formats, or evolutionary
> changes in format.  It is also (once one is
> familiar with regexes -- a useful skill outside
> of Python too) easier to get right (at least in
> a simple case like this.)
The posted regex doesn't work; this might be homework, so
I'll not fix the two problems.  The fact that you did not
see the failure weakens your claim of "does so very clearly."

--Scott David Daniels
Scott.Daniels at Acm.Org


From pfeldman at verizon.net  Fri Jul 24 11:58:36 2009
From: pfeldman at verizon.net (Phillip M. Feldman)
Date: Fri, 24 Jul 2009 10:58:36 -0500 (CDT)
Subject: len() should always return something
Message-ID: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>

An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090724/6d9321db/attachment-0001.html>

From Scott.Daniels at Acm.Org  Fri Jul 24 12:06:54 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 24 Jul 2009 09:06:54 -0700
Subject: Predefined Variables
In-Reply-To: <h49m7d$mch$1@foggy.unx.sas.com>
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
	<h49m7d$mch$1@foggy.unx.sas.com>
Message-ID: <iuKdnQ7T36jaR_TXnZ2dnUVZ_uSdnZ2d@pdx.net>

Stephen Cuppett (should have written in this order):
> "Fred Atkinson" <fatkinson at mishmash.com> wrote ...
>> Is there a pre-defined variable that returns the GET line
>>
>> (http://www.php.net/index.php?everythingafterthequestionmark) as a
>> single variable (rather than individual variables)?

 > os.environment('QUERY_STRING')

Maybe you mean:
     os.environ['USER']

--Scott David Daniels
Scott.Daniels at Acm.Org


From timlee126 at yahoo.com  Fri Jul 24 12:24:44 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 24 Jul 2009 09:24:44 -0700 (PDT)
Subject: Popen
Message-ID: <987525.41038.qm@web63102.mail.re1.yahoo.com>


Thanks! 
Yes I mean subprocess.Popen.

I was wondering the meaning of "asynchronously"
Here is some code I am reading recently:
"
result = Popen(cmdline,shell=True,stdout=PIPE).stdout 
for line in result.readlines():
    if find(line,"Cross") != -1:
        return float(split(line)[-1][0:-1]) 
"
The computation in the program "cmdline" takes a long time, at the end of which the results will be output to stdout.

"asynchronous" seems to mean Popen returns to the parent process immediately and the parent and child processes continue to be executed.
However, if Popen returns immediately to the parent process, then there will be nothing in "result", not to mention extracting information from the output. Thus it seems to me the parent process has to wait till the child process finish.

So how to understand the meaning of "asynchronous"?

Thanks and regards!


--- On Fri, 7/24/09, Kushal Kumaran <kushal.kumaran+python at gmail.com> wrote:

> From: Kushal Kumaran <kushal.kumaran+python at gmail.com>
> Subject: Re: Popen
> To: "Tim" <timlee126 at yahoo.com>
> Cc: python-list at python.org
> Date: Friday, July 24, 2009, 10:58 AM
> On Fri, Jul 24, 2009 at 7:33 PM,
> Tim<timlee126 at yahoo.com>
> wrote:
> >
> > Hi,
> > I wonder if I use Popen, the parent process will wait
> for the child process to finish or continue without
> waiting?
> > Thanks and regards!
> >
> 
> Assuming you mean subprocess.Popen, the child is executed
> asynchronously.? You can use the wait() method on the
> Popen object if
> you want the parent to wait for the child to finish.
> 
> -- 
> kushal
> 


      


From deets at nospam.web.de  Fri Jul 24 12:35:56 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 18:35:56 +0200
Subject: Popen
In-Reply-To: <mailman.3664.1248452692.8015.python-list@python.org>
References: <mailman.3664.1248452692.8015.python-list@python.org>
Message-ID: <7cu67cF29g680U1@mid.uni-berlin.de>

Tim schrieb:
> Thanks! 
> Yes I mean subprocess.Popen.
> 
> I was wondering the meaning of "asynchronously"
> Here is some code I am reading recently:
> "
> result = Popen(cmdline,shell=True,stdout=PIPE).stdout 
> for line in result.readlines():
>     if find(line,"Cross") != -1:
>         return float(split(line)[-1][0:-1]) 
> "
> The computation in the program "cmdline" takes a long time, at the end of which the results will be output to stdout.
> 
> "asynchronous" seems to mean Popen returns to the parent process immediately and the parent and child processes continue to be executed.
> However, if Popen returns immediately to the parent process, then there will be nothing in "result", not to mention extracting information from the output. Thus it seems to me the parent process has to wait till the child process finish.
> 
> So how to understand the meaning of "asynchronous"?

"Asynchronous" means asynchronous - the parent is *not* waiting.

Which is the reason that there is (amongst other things) the 
"wait"-method you can call to wait for the child to be terminated.

Diez


From bieffe62 at gmail.com  Fri Jul 24 12:40:22 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Fri, 24 Jul 2009 09:40:22 -0700 (PDT)
Subject: Popen
References: <mailman.3664.1248452692.8015.python-list@python.org>
Message-ID: <7df4ca4e-476a-4b3c-99d4-e710c75ab80b@o15g2000yqm.googlegroups.com>

On Jul 24, 6:24?pm, Tim <timlee... at yahoo.com> wrote:
> Thanks!
> Yes I mean subprocess.Popen.
>
> I was wondering the meaning of "asynchronously"
> Here is some code I am reading recently:
> "
> result = Popen(cmdline,shell=True,stdout=PIPE).stdout
> for line in result.readlines():
> ? ? if find(line,"Cross") != -1:
> ? ? ? ? return float(split(line)[-1][0:-1])
> "
> The computation in the program "cmdline" takes a long time, at the end of which the results will be output to stdout.
>
> "asynchronous" seems to mean Popen returns to the parent process immediately and the parent and child processes continue to be executed.

This is correct

> However, if Popen returns immediately to the parent process, then there will be nothing in "result", not to mention extracting information from the output. Thus it seems to me the parent process has to wait till the child process finish.
>

Calling result.readlines() the parent process attempts to read from
stdout until end of file. For a pipe, end of file means that
the other end is closing its connection, which - unless the child
process closes stdout  explicitely - means that the child
process is terminated.
So the end effect is the almost like  using 'communicate' on the
result of Popen, except that communicates returns both standard output
and standard error contents at the same time.



> So how to understand the meaning of "asynchronous"?
>
> Thanks and regards!

HTH

Ciao
-----
FB


From mathieu.malaterre at gmail.com  Fri Jul 24 12:48:22 2009
From: mathieu.malaterre at gmail.com (mathieu)
Date: Fri, 24 Jul 2009 09:48:22 -0700 (PDT)
Subject: SONAME for python modules is bad? (aka multiple module version)
Message-ID: <2a2a36ca-72a0-470f-907c-2be43104617a@h18g2000yqj.googlegroups.com>

As far as I know there has not been any consensus on how to install
multiple version of a same module in python ? What are the recommended
mechanism ?

I could not find any documentation on the subject. Does anyone sees
any issue with using standard SONAME mechanism when installing a
python module ?

Thanks,

ref:
http://mail.python.org/pipermail/pythonmac-sig/2009-January/020936.html


From timlee126 at yahoo.com  Fri Jul 24 12:52:01 2009
From: timlee126 at yahoo.com (Tim)
Date: Fri, 24 Jul 2009 09:52:01 -0700 (PDT)
Subject: Popen
Message-ID: <414673.50429.qm@web63108.mail.re1.yahoo.com>


Thanks! If that is the case, i.e. the parent doesn't wait, is the code in my last post wrong? "result" could be nothing.

--- On Fri, 7/24/09, Diez B. Roggisch <deets at nospam.web.de> wrote:

> From: Diez B. Roggisch <deets at nospam.web.de>
> Subject: Re: Popen
> To: python-list at python.org
> Date: Friday, July 24, 2009, 12:35 PM
> Tim schrieb:
> > Thanks! Yes I mean subprocess.Popen.
> > 
> > I was wondering the meaning of "asynchronously"
> > Here is some code I am reading recently:
> > "
> > result = Popen(cmdline,shell=True,stdout=PIPE).stdout
> for line in result.readlines():
> >? ???if find(line,"Cross") != -1:
> >? ? ? ???return
> float(split(line)[-1][0:-1]) "
> > The computation in the program "cmdline" takes a long
> time, at the end of which the results will be output to
> stdout.
> > 
> > "asynchronous" seems to mean Popen returns to the
> parent process immediately and the parent and child
> processes continue to be executed.
> > However, if Popen returns immediately to the parent
> process, then there will be nothing in "result", not to
> mention extracting information from the output. Thus it
> seems to me the parent process has to wait till the child
> process finish.
> > 
> > So how to understand the meaning of "asynchronous"?
> 
> "Asynchronous" means asynchronous - the parent is *not*
> waiting.
> 
> Which is the reason that there is (amongst other things)
> the "wait"-method you can call to wait for the child to be
> terminated.
> 
> Diez
> -- http://mail.python.org/mailman/listinfo/python-list
> 


      


From marcusw at cox.net  Fri Jul 24 12:57:57 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 24 Jul 2009 12:57:57 -0400
Subject: any suggestions to synchronize typed text and speech ?
In-Reply-To: <mailman.3473.1248192801.8015.python-list@python.org>
References: <mailman.3406.1248034495.8015.python-list@python.org>	<h40adj$bv6$1@adenine.netfront.net>	<mailman.3419.1248082444.8015.python-list@python.org>	<h428fp$8ja$2@adenine.netfront.net>
	<mailman.3473.1248192801.8015.python-list@python.org>
Message-ID: <h4cp6l$2khu$1@adenine.netfront.net>

On 7/21/2009 12:13 PM, Stef Mientki wrote:
> hi Marcus,
>>>> That sounds like a very specialized type of thing, 
>>> Well from an application point of view,
>>> with the current netbooks,
>>> this looks like a perfect tool for any conversation or meeting.
>>>> which only the few people with experience with wxPython, PyAudio, 
>>>> and Scintilla could help you with...
>>>>
>>> I was afraid of that too, so I dropped the question in several places,
>>> and the writer of Scintilla himself came with the perfect answer.
>>>
>>> cheers,Stef
>>>> But you might try having a dictionary with notes and associated 
>>>> times, or just give each note a four-digit ID number at the 
>>>> beginning of it when it's entered and use that in the dictionary (to 
>>>> keep keys shorter). Or you could just do a little hack and increase 
>>>> the number of bookmarks allowed (seeing as source is available) :p
>>>>
>>>> Marcus
>>>
>> Glad you got a good answer from somebody. Sounds like an interesting 
>> project. About when would this be headed for a release? Could you post 
>> a link to a googlecode or sourceforge project or something so I can 
>> follow and/or help with development?
>>
> For the moment it's just an idea, so no line of code yet.
> I first like to tackle all the problems,
> at least to the level I think I can handle them.
> So first solve the next problem,
> before I start coding:
> automatic synchronization (file uploading and deleting) between EEE-pc 
> and desktop PC over bluetooth.
> And another problem, as my customers are physicians,
> both the text and audio need to be stored encrypted.
> 
> cheers,
> Stef
>> Marcus
> 
I would recommend pybluez and 
http://www.google.com/search?q=python+aes+encryption

Marcus


From kyrie at uh.cu  Fri Jul 24 13:00:38 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Fri, 24 Jul 2009 13:00:38 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<mailman.3570.1248335976.8015.python-list@python.org>
	<f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
Message-ID: <200907241300.38738.kyrie@uh.cu>

On Friday 24 July 2009 11:07:30 am Inky 788 wrote:
> On Jul 23, 3:42?am, Hendrik van Rooyen <hend... at microcorp.co.za>
> > if you think it is contrived, then please consider how you would
> > keep track of say the colour of a pixel on a screen at position
> > (x,y) - this is about the simplest "natural" tuple format and
> > example.
>
> My guess is that this is probably the way most people do it:
[...]
> def make_array_of_pixels(num_columns, num_rows):
[...]

If you need to hold /every/ pixel on the screen, it makes sense to have a 
bidimentional array of points and colors. But if you need to hold a 
non-rectangular subset, or even a subset that doesn't need to be rectangular, 
you can either use dicts, or ... do what you did. Most people will use the 
less contrived version of:

screen = {}
screen[1,2] = (rand(), rand(), rand())

(btw, in your make_a_pixel function, unless you want to make the pixels 
updatable in place, you should also be using a tuple).

Sparse datasets are extremely common, and dicts are a good way to 
[temporarily] store them.

As someone mentioned before, dictionaries are essential to python. Don't go 
out of your way to avoid them, unless you have a /reason/ to do it.

Btw,

def get_color(point):
    return screen[point]

is way more readable (and less obscure) than

def get_color(point):
    return rows_of_pixels[point[0]][point[1]]

Regards,
-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From clp2 at rebertia.com  Fri Jul 24 13:02:30 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 10:02:30 -0700
Subject: effbot.org broken (WAS: Problems in commands.getoutput(cmd) with 
	sox)
In-Reply-To: <m2ljmeifo4.fsf@cs.uu.nl>
References: <mailman.3620.1248378772.8015.python-list@python.org>
	<m2ljmeifo4.fsf@cs.uu.nl>
Message-ID: <50697b2c0907241002o1cd9f262h853c2abe2ce534f6@mail.gmail.com>

On Fri, Jul 24, 2009 at 2:38 AM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Chris Rebert <clp2 at rebertia.com> (CR) wrote:
>
>>CR> On Thu, Jul 23, 2009 at 12:42 PM, Chris Rebert<clp2 at rebertia.com> wrote:
>>>> You can use tabnanny to help diagnose the problem:
>>>> http://74.125.155.132/search?q=cache:QtxvZm3QDLsJ:effbot.org/librarybook/tabnanny.htm+tabnanny&cd=3&hl=en&ct=clnk&gl=us&client=firefox-a
>
>>CR> Anyone know what's the deal with effbot.org? It seems to be broken at
>>CR> present, forcing me to use Google's cached version.
>>CR> It's a real shame since it has lots of handy Python info.
>
> Just try again.

Yup, whatever the problem was, seems to be fixed now. Interesting.

- Chris


From roastie57 at gmail.com  Fri Jul 24 13:14:31 2009
From: roastie57 at gmail.com (Uncle Roastie)
Date: Fri, 24 Jul 2009 10:14:31 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <0505d29f-edeb-40a4-b513-6117ecf4de33@m18g2000vbi.googlegroups.com>

On Jul 20, 12:27?pm, Phillip B Oldham <phillip.old... at gmail.com>
wrote:
> My colleagues and I have been working with python for around 6 months
> now, and while we love a lot of what python has done for us and what
> it enables us to do some of the decisions behind such certain
> data-types and their related methods baffle us slightly (when compared
> to the decisions made in other, similarly powerful languages).
>
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.
>
> Consider the following:
>
> >>> x = [2,1,3]
> >>> x.sort()
> >>> print x
>
> [1, 2, 3]
>
> Now, if the sort operations were unable to affect the original
> structure of the list (as in JavaScript) you'd effectively have a
> tuple which you could add/remove from, and the example above would
> look more like:
>
> >>> x = [2,1,3]
> >>> print x.sort()
> [1, 2, 3]
> >>> print x
>
> [2,1,3]
>
> This make a lot more sense to us, and follows the convention from
> other languages. It would also mean chaining methods to manipulate
> lists would be easier:
>
> >>> x = [2,1,3]
> >>> print x.sort()[0]
> 3
> >>> print x
>
> [2,1,3]
>
> We often find we need to do manipulations like the above without
> changing the order of the original list, and languages like JS allow
> this. We can't work out how to do this in python though, other than
> duplicating the list, sorting, reversing, then discarding.
>
> We're not looking to start any arguments or religious wars and we're
> not asking that python be changed into something its not. We'd simply
> like to understand the decision behind the lists and tuple structures.
> We feel that in not "getting" the difference between the two types we
> may be missing out on using these data structures to their full
> potential.

A tuple can be used like a struct in C - the number of fields is meant
to
be fixed and should not be dynamically changed.


From gert.cuykens at gmail.com  Fri Jul 24 13:22:36 2009
From: gert.cuykens at gmail.com (gert)
Date: Fri, 24 Jul 2009 10:22:36 -0700 (PDT)
Subject: cgi.fieldstorage()
Message-ID: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>

this is a non standard way to store multi part post data on disk

def application(environ, response):
    with open('/usr/httpd/var/wsgiTemp','w') as f:
        while True:
            chunk = environ['wsgi.input'].read(8192).decode('latin1')
            if not chunk: break
            f.write(chunk)
    response('200 OK',[])
    return ['complete']

my question is how do i handle the file, so i can shuffle it into a db
using small chunks of memorie ?


From deets at nospam.web.de  Fri Jul 24 13:27:16 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 19:27:16 +0200
Subject: SONAME for python modules is bad? (aka multiple module version)
In-Reply-To: <2a2a36ca-72a0-470f-907c-2be43104617a@h18g2000yqj.googlegroups.com>
References: <2a2a36ca-72a0-470f-907c-2be43104617a@h18g2000yqj.googlegroups.com>
Message-ID: <7cu97kF29dnlbU1@mid.uni-berlin.de>

mathieu schrieb:
> As far as I know there has not been any consensus on how to install
> multiple version of a same module in python ? What are the recommended
> mechanism ?


I use virtualenvs for everything. Especially on unixish OSes this 
usually works without problems. On windows, things are a bit different, 
as sometimes you only get binary installers that insist on installing 
into the base-installation.

> I could not find any documentation on the subject. Does anyone sees
> any issue with using standard SONAME mechanism when installing a
> python module ?


I don't understand that. You mean the .so.X.Y.Z-thingy under *ix? That 
would essentially be the pkg_resources.require-road, yes. But as it's 
not widely adopted, it will cause you troubles because some packages 
won't declare their dependencies properly.

Diez


From clp2 at rebertia.com  Fri Jul 24 13:28:10 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 10:28:10 -0700
Subject: Popen
In-Reply-To: <414673.50429.qm@web63108.mail.re1.yahoo.com>
References: <414673.50429.qm@web63108.mail.re1.yahoo.com>
Message-ID: <50697b2c0907241028s4f3ff1e6ma4f78ae2b61b2341@mail.gmail.com>

> --- On Fri, 7/24/09, Diez B. Roggisch <deets at nospam.web.de> wrote:
>
>> From: Diez B. Roggisch <deets at nospam.web.de>
>> Subject: Re: Popen
>> To: python-list at python.org
>> Date: Friday, July 24, 2009, 12:35 PM
>> Tim schrieb:
>> > Thanks! Yes I mean subprocess.Popen.
>> >
>> > I was wondering the meaning of "asynchronously"
>> > Here is some code I am reading recently:
>> > "
>> > result = Popen(cmdline,shell=True,stdout=PIPE).stdout
>> for line in result.readlines():
>> >? ???if find(line,"Cross") != -1:
>> >? ? ? ???return
>> float(split(line)[-1][0:-1]) "
>> > The computation in the program "cmdline" takes a long
>> time, at the end of which the results will be output to
>> stdout.
>> >
>> > "asynchronous" seems to mean Popen returns to the
>> parent process immediately and the parent and child
>> processes continue to be executed.
>> > However, if Popen returns immediately to the parent
>> process, then there will be nothing in "result", not to
>> mention extracting information from the output. Thus it
>> seems to me the parent process has to wait till the child
>> process finish.
>> >
>> > So how to understand the meaning of "asynchronous"?
>>
>> "Asynchronous" means asynchronous - the parent is *not*
>> waiting.
>>
>> Which is the reason that there is (amongst other things)
>> the "wait"-method you can call to wait for the child to be
>> terminated.

On Fri, Jul 24, 2009 at 9:52 AM, Tim<timlee126 at yahoo.com> wrote:
>
> Thanks! If that is the case, i.e. the parent doesn't wait, is the code in my last post wrong? "result" could be nothing.

No, it will be a subprocess.Popen object representing the spawned
process. Both the child process and the parent Python process will
then be running simultaneously.This allows the Python program to
interact with the subprocess via the Popen object while the subprocess
is executing in parallel with Python.
The asynchronicity means that the call to the Popen constructor does
not wait for the spawned subprocess to terminate before returning the
new Popen object to the parent Python program.

Cheers,
Chris
-- 
http://blog.rebertia.com


From deets at nospam.web.de  Fri Jul 24 13:32:31 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 24 Jul 2009 19:32:31 +0200
Subject: cgi.fieldstorage()
In-Reply-To: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
Message-ID: <7cu9hhF29gt65U1@mid.uni-berlin.de>

gert schrieb:
> this is a non standard way to store multi part post data on disk
> 
> def application(environ, response):
>     with open('/usr/httpd/var/wsgiTemp','w') as f:
>         while True:
>             chunk = environ['wsgi.input'].read(8192).decode('latin1')
>             if not chunk: break
>             f.write(chunk)
>     response('200 OK',[])
>     return ['complete']
> 
> my question is how do i handle the file, so i can shuffle it into a db
> using small chunks of memorie ?

I don't think that's possible with the current DB-API. There is no 
stream-based BLOB-interface (as e.g. JDBC offers).

So the answer certainly depends on your used RDBMS. For oracle, you 
would be lucky:

http://cx-oracle.sourceforge.net/html/lob.html


Other adapters I don't know about.

Diez


From clp2 at rebertia.com  Fri Jul 24 13:41:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 10:41:13 -0700
Subject: trouble with wrapping a c program
In-Reply-To: <20090724123458.TOWM14607.viefep17-int.chello.at@edge02.upc.biz>
References: <20090724123458.TOWM14607.viefep17-int.chello.at@edge02.upc.biz>
Message-ID: <50697b2c0907241041l10d13f09pa01abb505461e737@mail.gmail.com>

On Fri, Jul 24, 2009 at 5:34 AM, Sanne Korzec<sanne at kortec.nl> wrote:
> Hi Mailing,
>
> I am using a c program, which first initializes for some seconds and then
> waits for user input (keyboard) to type something. When enter is pressed the
> c program continues.
<snip>
> Using the keyboard and then enter in the c program prompt works, but I wish
> to do this from the python script by sending the string from the python
> script.
>
> I am able to print the string from python with a print command or with a
> stdout.write command. But this simply prints it to the prompt, the c program
> does nothing with this printed string.
>
> Is there a way to pipe, stream, or send this string to the running c
> program?
<snip>
> Here is a small fragment of my code:
>
> #initialization
>
> cmd = [a list of my program and arguments]
>
> subprocess.Popen(cmd)?? #starts the c program

import subprocess
cmd = [a list of my program and arguments]
process = subprocess.Popen(cmd, stdin=subprocess.PIPE)   #starts the c program
line = raw_input("Please enter a line of input for the C program:")
process.stdin.write(line)
process.stdin.write("\n")

You might want to study the docs for the subprocess module:
http://docs.python.org/library/subprocess.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From kyrie at uh.cu  Fri Jul 24 13:46:10 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Fri, 24 Jul 2009 13:46:10 -0400
Subject: len() should always return something
In-Reply-To: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
Message-ID: <200907241346.10966.kyrie@uh.cu>

On Friday 24 July 2009 11:58:36 am Phillip M. Feldman wrote:
> I've been converting Matlab codes to Python.? In Matlab, a scalar is just a
> one-by-one matrix and has a length of 1.? This convention seems no less
> arbitrary to me than Python's convention that the concept of length is not
> applicable to ints and floats.

Are you sure it isn't? (as opposed to being tainted by matlab?).

Almost everywhere, a scalar and a tuple are different things. How many 
elements are "inside" the number 7? If you assume that 7 is a matrix, why 
should it be a two-dimensional matrix? Why not a vector, or a three 
dimensional matrix instead? (I don't use matlab, but in octave, size(7) 
returns [1,1], not [1] or [1,1,1,1]).

That seems even more arbitrary to me. Of course, in a language like Matlab, 
that assumes that everything is a matrix, it makes sense for scalars to be 
mapped to a useful matrices. But that assumption is not natural.

Even pure math makes a difference between scalars and vectors. Matrix x Matrix 
multiplication is not always defined (even when the second matrix contains 
exactly one element), while Matrix x Scalar always is. (Octave, btw, will 
demote a two-dimensional 1x1 matrix to a scalar for Matrix multiplication, 
which may hide errors)

If you are converting from matlab, I'd say you have biggest things to worry 
about. As you said, you can just replace the len function (even safer may be 
to do [1]). Assignment, for instance, is /very/ different.

> If there is only a single measurement, it is reasonable to allow the calling 
> program to pass a scalar without wrapping it up into a list or array.

I try to avoid those automatic conversions, on the long run, I believe that 
most of them make the code more confusing for the caller. If you feel that 
you must allow that, my suggestion would be to create a method that will 
ensure that what you receive is a list (or whatever) and coerce its argument 
if not, and call that one at the beginning of your methods.

Regards,

[1] this will define len for any object, not only int and floats.
===
def size(x):
    try:
        return len(x)
    except TypeError:
        return 1,1
===

-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From rhodri at wildebst.demon.co.uk  Fri Jul 24 13:52:41 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 18:52:41 +0100
Subject: len() should always return something
In-Reply-To: <m2r5w6glrk.fsf@cs.uu.nl>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<m2r5w6glrk.fsf@cs.uu.nl>
Message-ID: <op.uxk2l3tta8ncjz@gnudebst>

On Fri, 24 Jul 2009 16:10:07 +0100, Piet van Oostrum <piet at cs.uu.nl> wrote:

>>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:
>
>> RJ> On Fri, 24 Jul 2009 14:57:02 +0100, Grant Edwards <invalid at invalid>  
>> wrote:
>>>> On 2009-07-24, Dr. Phillip M. Feldman <pfeldman at verizon.net> wrote:
>>>>>
>>>>> Some aspects of the Python design are remarkably clever, while
>>>>> others leave me perplexed. Here's an example of the latter:
>>>>> Why does len() give an error when applied to an int or float?
>>>>> len() should always return something; in particular, when
>>>>> applied to a scalar, it should return a value of 1.
>>>>
>>>> If len(7) returned a value of 1, then wouldn't one expect 7[0]
>>>> to be valid?  It isn't, so you'd then have to redefine all
>>>> types so that they are sequences that can be indexed.  Sounds
>>>> like a big mess to me...
>>>>
>>>> [Are there types for which len() returns a value that can't be
>>>> indexed?]
>>>>
>
>> RJ> Dictionaries.
>
>> RJ> Which doesn't make your point less valid.  In fact I'd go so
>> RJ> far as to argue that what len() gives you is the number of
>> RJ> items in a container, so len(7) should return 0.
>
> But len(7) could as well be defined as 3, 1, 32, or 64 (depending on the
> implementation). Therefore it doesn't make much sense.

Quite.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From andre.roberge at gmail.com  Fri Jul 24 13:54:21 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Fri, 24 Jul 2009 10:54:21 -0700 (PDT)
Subject: ElementTree's Element substitution in Python 3
Message-ID: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>

I have a function to replace the content of an ElementTree Element by
that of another one which works using Python 2 but not with Python 3.
I get an assertion error.  The function is as follows:

def replace_element(elem, replacement):
    '''replace the content of an ElementTree Element by that of
another
       one.
    '''
    elem.clear()
    elem.text = replacement.text
    elem.tail = replacement.tail
    elem.tag = replacement.tag
    elem.attrib = replacement.attrib
    elem[:] = replacement[:]

The last line is problematic.  For example, if I do the following
program with Python2.5
###
from xml.etree import ElementTree as et

a = et.Element('a')
b = et.SubElement(a, 'b')
c = et.Element('c')

a[:] = c[:]
###
nothing of note happens - however, doing the same with Python 3.1, I
get the following traceback:

Traceback (most recent call last):
  File "test.py", line 7, in <module>
    a[:] = c[:]
  File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
210, in __setitem__
    assert iselement(element)
AssertionError

======
I would gladly welcome any suggestion for writing a replace_element()
function that works with Python 3.1

Andr?


From ronn.ross at gmail.com  Fri Jul 24 13:56:29 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Fri, 24 Jul 2009 12:56:29 -0500
Subject: trouble with minidom
In-Reply-To: <op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
	<op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <9c8c445f0907241056x11ec5316s2ea6310872cd342@mail.gmail.com>

On Tue, Jul 21, 2009 at 7:32 PM, Gabriel Genellina
<gagsl-py2 at yahoo.com.ar>wrote:

> En Tue, 21 Jul 2009 21:08:57 -0300, Ronn Ross <ronn.ross at gmail.com>
> escribi?:
>
>
>  Hello I'm trying to read an xml file using minidome. The xml looks like:
>> <rootNode>
>>   <project>
>>      <name>myProj</name>
>>      <path>/here/</path>
>>   </project>
>> </rootNode>
>>
>> My code looks like so:
>> from xml.dom.minidom import parse
>>
>> dom = parse("myfile.xml")
>>
>> for node in dom.getElementsByTagName("project'):
>>   print('name: %s, path: %s \n') % (node.childNodes[0].nodeValue,
>> node.childNodes[1])
>>
>> Unfortunately, it returns 'nodeValue as none. I'm trying to read the value
>> out of the node fir example name: myProj. I haven't found much help in the
>> documentation. Can someone point me in the right direction?
>>
>
> Unless you have a specific reason to use the DOM interface (like having a
> masochistic mind), working with ElementTree usually is a lot easier:
>
> py> import xml.etree.ElementTree as ET
> py> xml = """<rootNode>
> ... <project>
> ...        <name>myProj</name>
> ...        <path>/here/</path>
> ... </project>
> ... </rootNode>"""
> py> doc = ET.fromstring(xml)
> py> for project in doc.findall('project'):
> ...   for child in project.getchildren():
> ...     print child.tag, child.text
> ...
> name myProj
> path /here/
>
> --
> Gabriel Genellina
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


I have used the loop below and it works great, but I need get both child
elements or 'project' per iteration. I want to build a dictionary that
resemble this:
my_dict = {'myProj':'/here/', 'anothername':'anotherpath'}

I couldn't find how to do with in the element tree docs. Can you point me in
the right direction?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090724/043fd697/attachment-0001.html>

From clp2 at rebertia.com  Fri Jul 24 14:03:59 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 11:03:59 -0700
Subject: len() should always return something
In-Reply-To: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
Message-ID: <50697b2c0907241103v5ad12d48re1857532c58903e8@mail.gmail.com>

> Jul 24, 2009 07:02:29 AM, clp2 at rebertia.com wrote:
>
> On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
> Feldman<pfeldman at verizon.net> wrote:
>>
>> Some aspects of the Python design are remarkably clever, while others
>> leave
>> me perplexed. Here's an example of the latter: Why does len() give an
>> error
>> when applied to an int or float? len() should always return something; in
>> particular, when applied to a scalar, it should return a value of 1. Of
>> course, I can define my own function like this:
>>
>> def mylen(x):
>> ? if isinstance(x,int) or isinstance(x,float): return 1
>> ? return len(x)
>>
>> But, this shouldn't be necessary.
>
> The problem is that redefining len()/length/size that way would
> violate several principles of Python's design (The "Zen" of Python -
> http://www.python.org/dev/peps/pep-0020/).
>
> Specifically:
> - Explicit is better than implicit.
> - Special cases aren't special enough to break the rules.
> - Errors should never pass silently.
> - In the face of ambiguity, refuse the temptation to guess.
>
> If you'd explain the situation that prompts you to find this
> redefinition necessary, I'm sure someone can suggest a better
> approach.

On Fri, Jul 24, 2009 at 8:58 AM, Phillip M. Feldman<pfeldman at verizon.net> wrote:
> I've read the "Zen of Python", but most of these aphorisms are vague and
> could be understood differently by different readers.  In particular, I
> don't understand the statement that "explicit is better than implicit".
> Some examples of this would be helpful.
>
> I've been converting Matlab codes to Python.  In Matlab, a scalar is just a
> one-by-one matrix and has a length of 1.  This convention seems no less
> arbitrary to me than Python's convention that the concept of length is not
> applicable to ints and floats.  My workaround was to write the following
> function:
>
> def is_scalar(x):
>    """Return True if x is an instance of int, float, or complex.
>    Otherwise, return False.  Note: If x is a length-1 list or array
>    containing an int, float, or complex value, False is returned."""
>    if isinstance(x,int) or isinstance(x,float) or isinstance(x,complex):
>       return True
>    return False
>
> The application is the following: In various types of scientific
> applications, one operates on a list of measurements.  If there is only a
> single measurement, it is reasonable to allow the calling program to pass a
> scalar without wrapping it up into a list or array.

You could use Python's extended call syntax when defining your function:

def average(*args):
    return sum(args) / len(args)

average(7) #==> 7
average(2,3,4,5,6) #==> 4
average(*[2,3,4,5,6]) #==> 4
average([2,3,4,5,6]) #==> error

Cheers,
Chris
-- 
http://blog.rebertia.com


From rhodri at wildebst.demon.co.uk  Fri Jul 24 14:05:58 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 24 Jul 2009 19:05:58 +0100
Subject: non-owning references?
In-Reply-To: <m23a8mi0m9.fsf@cs.uu.nl>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
	<mailman.3662.1248445305.8015.python-list@python.org>
	<m23a8mi0m9.fsf@cs.uu.nl>
Message-ID: <op.uxk278dca8ncjz@gnudebst>

On Fri, 24 Jul 2009 16:03:58 +0100, Piet van Oostrum <piet at cs.uu.nl> wrote:

>>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:
>
>> RJ> On Fri, 24 Jul 2009 14:55:45 +0100, Hrvoje Niksic  
>> <hniksic at xemacs.org>  wrote:
>>>> Ben Finney <ben+python at benfinney.id.au> writes:
>>>>
>>>>> Utpal Sarkar <doetoe at gmail.com> writes:
>>>>>
>>>>>> Is there a way I can tell a variable that the object it is pointing
>>>>>> too is not owned by it, in the sense that if it is the only  
>>>>>> reference
>>>>>> to the object it can be garbage collected?
>>>>>
>>>>> Python doesn't have ?pointers?, and doesn't really have ?variables?
>>>>> either, at least not how many other languages use that term.
>>>>
>>>> The OP didn't use the term "pointer", but the word "pointing", which
>>>> makes sense in the context.  The term "variable" is used in the Python
>>>> language reference and elsewhere, and is quite compatible with how  
>>>> other
>>>> popular languages (Java, PHP, Lisp, ...) use it.
>
>> RJ> Only superficially.  Treating Python variables the same as C  
>> variables
>> RJ> (say) is one of the classic ways that newbies come unstuck when  
>> mutable
>> RJ> objects appear on the scene.  While the OP appears to have the  
>> right idea,
>> RJ> your "correction" here could be quite misleading.
>
> If you read the OP, it is clear that he talked about a class variable,
> which is a perfectly legal notion in Python, and is mentioned as such in
> the language reference manual:
> `Variables defined in the class definition are class variables'

Yes.  I didn't think I needed to say that explicitly.

> And who was talking about C variables?

Hrvoje, implicitly.  'The term "variable" is used in the Python
language reference and elsewhere, and is quite compatible with how
other popular languages (Java, PHP, Lisp, ...) use it.'  I listed
C as another example of a popular language because I am very familiar
with how C's variables work; I don't know Java, I've never programmed
PHP in anger and it's twenty years since I last touched Lisp.

The point was, and remains, that this newsgroup gets regular traffic
 from people who expect Python's variables to act like C's variables,
demonstrating that describing them as "quite compatible" is somewhat
misleading.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Fri Jul 24 14:06:32 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Fri, 24 Jul 2009 14:06:32 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
Message-ID: <h4ctjv$bhj$1@news.eternal-september.org>

On 2009-07-23 23:51:02 -0400, Carl Banks <pavlovevidence at gmail.com> said:

> On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
>> fft1976 wrote:
>>> How do you explain that something as inferior as Python beat Lisp in
>>> the market place despite starting 40 years later.
>> 
>> Probably due to similar reasons that lead php to become remotely relevant
> .
> 
> Well, the only reason PHP became relevant because it was an


> easy

^^^^^^^^
^^^^^^^^ (emphasis added)

> to
> deploy solution in a single application domain, the web, that happened
> to explode.


i.e., Python "beat" lisp because it is ~70% of lisp in a form that is 
much more palatable to the average programmer, just as php became 
popular because it is powerful enough to do websites and, most 
importantly, apprehensible to mediocre programmers and even some 
non-programmers.

-- 
Raffael Cavallaro



From gert.cuykens at gmail.com  Fri Jul 24 14:10:17 2009
From: gert.cuykens at gmail.com (gert)
Date: Fri, 24 Jul 2009 11:10:17 -0700 (PDT)
Subject: cgi.fieldstorage()
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
Message-ID: <f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>

On Jul 24, 7:32?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> gert schrieb:
>
> > this is a non standard way to store multi part post data on disk
>
> > def application(environ, response):
> > ? ? with open('/usr/httpd/var/wsgiTemp','w') as f:
> > ? ? ? ? while True:
> > ? ? ? ? ? ? chunk = environ['wsgi.input'].read(8192).decode('latin1')
> > ? ? ? ? ? ? if not chunk: break
> > ? ? ? ? ? ? f.write(chunk)
> > ? ? response('200 OK',[])
> > ? ? return ['complete']
>
> > my question is how do i handle the file, so i can shuffle it into a db
> > using small chunks of memorie ?
>
> I don't think that's possible with the current DB-API. There is no
> stream-based BLOB-interface (as e.g. JDBC offers).
>
> So the answer certainly depends on your used RDBMS. For oracle, you
> would be lucky:
>
> http://cx-oracle.sourceforge.net/html/lob.html
>
> Other adapters I don't know about.

sqlite :) ok let say for now it would be impossible on a db level, but
before i reach the impossible, i still need to parse the file to
prepare the chunks. How do i do that ? How do i get the chunks without
loading the hole file into memorie ?

    b = environ['CONTENT_TYPE'].split('boundary=')[1]
    data = search(b+r'.*?Content-Type: application/octet-stream\r\n\r
\n
(.*?)\r\n--'+b,t,DOTALL).group(1)
    data = data.encode('latin1')


From jakecjacobson at gmail.com  Fri Jul 24 14:24:58 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Fri, 24 Jul 2009 11:24:58 -0700 (PDT)
Subject: exceptions.TypeError an integer is required
Message-ID: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>

I am trying to do a post to a REST API over HTTPS and requires the
script to pass a cert to the server.  I am getting
"exceptions.TypeError an integer is required" error and can't find the
reason.  I commenting out the lines of code, it is happening on the
connection.request() line.  Here is the problem code.  Would love some
help if possible.

	head = {"Content-Type" : "application/x-www-form-urlencoded",
"Accept" : "text/plain"}
	parameters = urlencode({"collection" : collection, "entryxml" : open
(file,'r').read()})
	try:
		connection = httplib.HTTPSConnection(host, port, key_file,
cert_file)
		connection.request('POST', path, parameters, head)
		response = connection.getresponse()
		print response.status, response.reason
	except:
		print sys.exc_type, sys.exc_value

	connection.close()


From piet at cs.uu.nl  Fri Jul 24 14:39:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 20:39:46 +0200
Subject: Predefined Variables
References: <p2qg65d0t4kki1sh0t3v6ileamhkvl9hgj@4ax.com>
	<h49m7d$mch$1@foggy.unx.sas.com>
	<iuKdnQ7T36jaR_TXnZ2dnUVZ_uSdnZ2d@pdx.net>
Message-ID: <m2hbx2gc25.fsf@cs.uu.nl>

>>>>> Scott David Daniels <Scott.Daniels at Acm.Org> (SDD) wrote:

>SDD> Stephen Cuppett (should have written in this order):
>>> "Fred Atkinson" <fatkinson at mishmash.com> wrote ...
>>>> Is there a pre-defined variable that returns the GET line
>>>> 
>>>> (http://www.php.net/index.php?everythingafterthequestionmark) as a
>>>> single variable (rather than individual variables)?

>>> os.environment('QUERY_STRING')

>SDD> Maybe you mean:
>SDD>     os.environ['USER']

Let's take the best of both:

os.environ['QUERY_STRING']
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From maymunbeyin at gmail.com  Fri Jul 24 14:51:54 2009
From: maymunbeyin at gmail.com (kk)
Date: Fri, 24 Jul 2009 11:51:54 -0700 (PDT)
Subject: How can I get the line number ?
Message-ID: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>

Hello

I am writing some Python code that runs in another application(has
wrapper functions). Due to lack of debugging I am printing out alot of
outputs and manual messages. I want to be able to create a function
that would let me print the current line number that is called from.
This is not for debugging exceptions it is rather to simplify my debug
messages, at least I can trace my debug messages.

thanks




From tjreedy at udel.edu  Fri Jul 24 14:52:38 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 14:52:38 -0400
Subject: len() should always return something
In-Reply-To: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
Message-ID: <h4cvtm$grr$1@ger.gmane.org>

Phillip M. Feldman wrote:

> I've been converting Matlab codes to Python.  In Matlab, a scalar is 
> just a one-by-one matrix and has a length of 1.  This convention seems 
> no less arbitrary to me than Python's convention that the concept of 
> length is not applicable to ints and floats.

Multiplication of a vector/matrix by a scalar always defined and 
commutative. Multiplication of a vector/matrix by a 1x1 matrix is not 
always even defined. So not having scalars in a matrix package strikes 
me as a bit odd.

 > My workaround was to write
> the following function:
> 
> def is_scalar(x):
>    """Return True if x is an instance of int, float, or complex.
>    Otherwise, return False.  Note: If x is a length-1 list or array
>    containing an int, float, or complex value, False is returned."""
>    if isinstance(x,int) or isinstance(x,float) or isinstance(x,complex):

Better:    if isinstance(x, (int, float, complex)):

but you forgot decimals and fractions and any other possible number modules.

In 3.1,
 >>> from numbers import Number
 >>> from decimal import Decimal
 >>> from fractions import Fraction
 >>> for x in 1, 1.0, (1+0j), Decimal(1), Fraction(1,1):
	isinstance(x, Number)

	
True
True
True
True
True

and the same for any other module that registers a class as a Number

>       return True
>    return False
> 
> The application is the following: In various types of scientific 
> applications, one operates on a list of measurements.  If there is only 
> a single measurement, it is reasonable to allow the calling program to 
> pass a scalar without wrapping it up into a list or array.

If you want to do that, start with

def f(x):
   try: len(x)
   except TypeError: x = x,

or in 3.1 use Number test above.

Terry Jan Reedy



From mkhitrov at gmail.com  Fri Jul 24 14:59:04 2009
From: mkhitrov at gmail.com (Maxim Khitrov)
Date: Fri, 24 Jul 2009 14:59:04 -0400
Subject: How can I get the line number ?
In-Reply-To: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>
References: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>
Message-ID: <26ddd1750907241159q3799e4c7k5a883d3b45feb4a5@mail.gmail.com>

On Fri, Jul 24, 2009 at 2:51 PM, kk<maymunbeyin at gmail.com> wrote:
> Hello
>
> I am writing some Python code that runs in another application(has
> wrapper functions). Due to lack of debugging I am printing out alot of
> outputs and manual messages. I want to be able to create a function
> that would let me print the current line number that is called from.
> This is not for debugging exceptions it is rather to simplify my debug
> messages, at least I can trace my debug messages.
>
> thanks

Modify the following as needed:

from inspect import currentframe, getframeinfo

def caller_info(depth=0):
	"""
	Get file, line number, and name of the calling function.
	"""
	if depth < 0:
		raise ValueError('invalid stack depth')

	caller = frame = currentframe()
	try:
		for i in xrange(-1, depth):
			caller = caller.f_back
			if caller is None:
				return (None, None, None)

		return getframeinfo(caller, 0)[:3]
	finally:
		del caller, frame

- Max


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 14:59:40 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 18:59:40 GMT
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <0279f596$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:

>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
> 
> and len("7") must return 8, by the same token... but wait!
> 
>  >>> len("7")
> 1
>  >>>
>  >>>
> my python installation must me outdated ;-)

No no no, you're obviously using an awesome version of Python that can 
compress single-character strings to a single bit!



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:00:14 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:00:14 GMT
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
Message-ID: <0279f5b9$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 15:55:45 +0200, Hrvoje Niksic wrote:

> The term "variable" is used in the Python
> language reference and elsewhere, and is quite compatible with how other
> popular languages (Java, PHP, Lisp, ...) use it.  Please stop
> complaining about valid terminology; it is not helpful.

No, the use of the single term "variable" to describe two distinct 
program models is not helpful. Whether other languages muddy the water 
between memory-location based variables and name-binding is irrelevant to 
whether we should do so. And quite a few of us are disappointed that the 
Python language reference should confuse the issue by using misleading 
terminology.

Unfortunately, the use of "variable" is so ingrained, and so simple 
compared to name binding terminology, that I fear we'll never eradicate 
it. I know sometimes I use it myself, but always with a little shiver of 
shame that I'm misusing terminology.



-- 
Steven


From robert.kern at gmail.com  Fri Jul 24 15:01:47 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 24 Jul 2009 14:01:47 -0500
Subject: Convert points to polygon shapefile
In-Reply-To: <20090724101638.E93B414B2A@smtp3.ualg.pt>
References: <20090724101638.E93B414B2A@smtp3.ualg.pt>
Message-ID: <h4d0er$hkh$1@ger.gmane.org>

On 2009-07-24 05:21, Luis Pedro Almeida wrote:
> Dear all,
>
> I would like to know how to convert a list of points into a polygon
> shapefile (esri).

shapelib has Python bindings.

   http://shapelib.maptools.org/

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From roy at panix.com  Fri Jul 24 15:03:29 2009
From: roy at panix.com (Roy Smith)
Date: Fri, 24 Jul 2009 15:03:29 -0400
Subject: list vs. tuple [Re: len() should always return something]
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<mailman.3674.1248461573.8015.python-list@python.org>
Message-ID: <roy-89AEB3.15032824072009@news.panix.com>

In article <mailman.3674.1248461573.8015.python-list at python.org>,
 Terry Reedy <tjreedy at udel.edu> wrote:

> Better:    if isinstance(x, (int, float, complex)):

I never noticed this before, but it seems odd that the second argument to 
isinstance() should be a tuple.  Using the normal arguments made about 
tuples vs. lists, it seems like a list would be the right data structure 
here.  I suppose a set would be even more right, but (I'm pretty sure) 
isinstance() predates sets.

I'm curious why a tuple was chosen.


From roy at panix.com  Fri Jul 24 15:04:55 2009
From: roy at panix.com (Roy Smith)
Date: Fri, 24 Jul 2009 15:04:55 -0400
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <roy-B8E460.15045524072009@news.panix.com>

In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
 Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:

> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
> 
> >> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
> > 
> > and len("7") must return 8, by the same token... but wait!
> > 
> >  >>> len("7")
> > 1
> >  >>>
> >  >>>
> > my python installation must me outdated ;-)
> 
> No no no, you're obviously using an awesome version of Python that can 
> compress single-character strings to a single bit!

Compressing strings to a single bit is easy.  It's the uncompressing that's 
tricky.


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:05:11 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:05:11 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
Message-ID: <0279f6df$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 00:02:28 -0700, Chris Rebert wrote:

> On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
> Feldman<pfeldman at verizon.net> wrote:
>>
>> Some aspects of the Python design are remarkably clever, while others
>> leave me perplexed. Here's an example of the latter: Why does len()
>> give an error when applied to an int or float? len() should always
>> return something; in particular, when applied to a scalar, it should
>> return a value of 1. Of course, I can define my own function like this:
>>
>> def mylen(x):
>> ? if isinstance(x,int) or isinstance(x,float): return 1 return len(x)
>>
>> But, this shouldn't be necessary.
> 
> The problem is that redefining len()/length/size that way would violate
> several principles of Python's design (The "Zen" of Python -
> http://www.python.org/dev/peps/pep-0020/).
> 
> Specifically:
> - Explicit is better than implicit.
> - Special cases aren't special enough to break the rules. 
> - Errors should never pass silently.
> - In the face of ambiguity, refuse the temptation to guess.


Chris, I'm curious why you think that these Zen are relevant to the OP's 
complaint.

Re explicit vs implicit, len(42) is just as explicit as len([42, 23]).

Arguably (I wouldn't argue this, but some people might) ints aren't 
"special enough" to break the rule that len(obj) should always return 
something.

(I don't actually agree, but some people might be able to produce a 
coherent argument why len() should apply equally to all objects.)

Re errors passing silently, the OP doesn't believe that len(42) should be 
an error, so that's not relevant.

And there's nothing ambiguous about len(42).

I agree with the current Python behaviour, but I don't think there's 
anything in the Zen to support it. As far as I know, there is no 
programming language which treats scalars like ints as if they were 
vectors of length 1, which makes Python's choice to make ints unlengthed 
a no-brainer.



-- 
Steven


From andre.roberge at gmail.com  Fri Jul 24 15:07:32 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Fri, 24 Jul 2009 12:07:32 -0700 (PDT)
Subject: ElementTree's Element substitution in Python 3
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
Message-ID: <9923e1c2-aabe-40d3-9c55-830991ad2dc9@q11g2000yqi.googlegroups.com>

Sorry for replying to myself ...  the following seems to be a working
solution to my original problem.
On Jul 24, 2:54?pm, Andr? <andre.robe... at gmail.com> wrote:
> I have a function to replace the content of an ElementTree Element by
> that of another one which works using Python 2 but not with Python 3.
> I get an assertion error. ?The function is as follows:
>
> def replace_element(elem, replacement):
> ? ? '''replace the content of an ElementTree Element by that of
> another
> ? ? ? ?one.
> ? ? '''
> ? ? elem.clear()
> ? ? elem.text = replacement.text
> ? ? elem.tail = replacement.tail
> ? ? elem.tag = replacement.tag
> ? ? elem.attrib = replacement.attrib
> ? ? elem[:] = replacement[:]
>

Use instead:

def replace_element(elem, replacement):
    '''replace the content of an ElementTree Element by that of
another
       one.
    '''
    elem.clear()
    elem.text = replacement.text
    elem.tail = replacement.tail
    elem.tag = replacement.tag
    elem.attrib = replacement.attrib
    try:
        elem[:] = replacement[:]  # works with Python 2.x (fast) but
not 3.x
    except AssertionError:
        del elem[:]
        for child in replacement:
            elem.append(child)


Andr?


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:11:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:11:33 GMT
Subject: exceptions.TypeError an integer is required
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
Message-ID: <0279f85d$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 11:24:58 -0700, jakecjacobson wrote:

> I am trying to do a post to a REST API over HTTPS and requires the
> script to pass a cert to the server.  I am getting "exceptions.TypeError
> an integer is required" error and can't find the reason.  I commenting
> out the lines of code, it is happening on the connection.request() line.
>  Here is the problem code.  Would love some help if possible.

Please post the traceback that you get.

My guess is that you are passing a string instead of an integer, probably 
for the port.


[...]
> 	except:
> 		print sys.exc_type, sys.exc_value

As a general rule, a bare except of that fashion is bad practice. Unless 
you can explain why it is normally bad practice, *and* why your case is 
an exception (no pun intended) to the rule "never use bare except 
clauses", I suggest you either:

* replace "except:" with "except Exception:" instead.

* better still, re-write the entire try block as:


    try:
        [code goes here]
    finally:
        connection.close()

and use the Python error-reporting mechanism instead of defeating it.



-- 
Steven


From piet at cs.uu.nl  Fri Jul 24 15:17:10 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 24 Jul 2009 21:17:10 +0200
Subject: ElementTree's Element substitution in Python 3
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
Message-ID: <m2d47phow9.fsf@cs.uu.nl>

>>>>> Andr? <andre.roberge at gmail.com> (A) a ?crit:

>A> I have a function to replace the content of an ElementTree Element by
>A> that of another one which works using Python 2 but not with Python 3.
>A> I get an assertion error.  The function is as follows:

>A> def replace_element(elem, replacement):
>A>     '''replace the content of an ElementTree Element by that of
>A> another
>A>        one.
>A>     '''
>A>     elem.clear()
>A>     elem.text = replacement.text
>A>     elem.tail = replacement.tail
>A>     elem.tag = replacement.tag
>A>     elem.attrib = replacement.attrib
>A>     elem[:] = replacement[:]

>A> The last line is problematic.  For example, if I do the following
>A> program with Python2.5
>A> ###
>A> from xml.etree import ElementTree as et

>A> a = et.Element('a')
>A> b = et.SubElement(a, 'b')
>A> c = et.Element('c')

>A> a[:] = c[:]
>A> ###
>A> nothing of note happens - however, doing the same with Python 3.1, I
>A> get the following traceback:

>A> Traceback (most recent call last):
>A>   File "test.py", line 7, in <module>
>A>     a[:] = c[:]
>A>   File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
>A> 210, in __setitem__
>A>     assert iselement(element)
>A> AssertionError

This is a Python bug. Please report it. The problem is that in Python 3
slice assignments are done with __setitem__ rather than __setslice__ but
ElementTree has not been adapted to that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From tjreedy at udel.edu  Fri Jul 24 15:17:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 15:17:15 -0400
Subject: Adding method from one class to another class or to instance
	of    another class
In-Reply-To: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
References: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
Message-ID: <h4d1br$ldd$1@ger.gmane.org>

marekw2143 wrote:
> Hi,
> 
> I have one class (A) that has defined method createVars. I would like
> to add that method to class B
> The code looks like this:
> 
> 
> class A(object):
>    def createVars(self):
>       self.v1 = 1
>       self.v2 = 3
>       pass
> 
> class B(object):
>    pass
> 
> 
> I don't want to use inheritance (because class A has many methods
> defined that class B doesn't need).
> When I try the folloowing:
> 
> 
> B.createVars = C.createVars

  you meant A.createVars

> B().createVars()
> 
> 
> then the following error occurs:
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unbound method createVars() must be called with A instance
> as first argument (got nothing instead)

In 3.1, your example works fine. The difference is that in 2.x, 
B.createVars is a method wrapperthat wraps the function, whereas in 3.1, 
it is the function itself. For 2.x, you need to extract the function 
from the wrapper. It is im_func or something like that. Use 
dir(B.createVars) to check for sure.

> How can I solve this problem?

Terry Jan Reedy



From linuxguy123 at gmail.com  Fri Jul 24 15:17:24 2009
From: linuxguy123 at gmail.com (Linuxguy123)
Date: Fri, 24 Jul 2009 13:17:24 -0600
Subject: Eclipse Pydev update error ?
Message-ID: <1248463044.8697.50.camel@localhost.localdomain>

Does anyone know why this error is occurring in my Eclipse Pydev
update ?

An error occurred while collecting items to be installed
  No repository found containing:
org.python.pydev/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.ast/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.core/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.debug/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.feature/org.eclipse.update.feature/1.4.7.2843
  No repository found containing:
org.python.pydev.help/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.jython/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.parser/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.refactoring/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.templates/osgi.bundle/1.4.7.2843
  No repository found containing:
org.python.pydev.customizations/osgi.bundle/1.4.7.2843

Thanks




From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 24 15:18:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 24 Jul 2009 19:18:09 GMT
Subject: list vs. tuple [Re: len() should always return something]
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<mailman.3674.1248461573.8015.python-list@python.org>
	<roy-89AEB3.15032824072009@news.panix.com>
Message-ID: <0279f9e9$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 15:03:29 -0400, Roy Smith wrote:

> In article <mailman.3674.1248461573.8015.python-list at python.org>,
>  Terry Reedy <tjreedy at udel.edu> wrote:
> 
>> Better:    if isinstance(x, (int, float, complex)):
> 
> I never noticed this before, but it seems odd that the second argument
> to isinstance() should be a tuple.  Using the normal arguments made
> about tuples vs. lists, it seems like a list would be the right data
> structure here.

What would be the point of using a list? You're never going to sort it, 
or append items to it, or otherwise mutate it. You build it, pass it to a 
function which doesn't modify it in any fashion, then it gets garbage 
collected.


> I suppose a set would be even more right, but (I'm
> pretty sure) isinstance() predates sets.

Yes.

[steve at sylar ~]$ python1.5
Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
4.1.2-27)] on linux2
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>> isinstance
<built-in function isinstance>
>>> set
Traceback (innermost last):
  File "<stdin>", line 1, in ?
NameError: set



> I'm curious why a tuple was chosen.

Tuples are smaller and faster to build than lists -- they're the most 
lightweight sequence type in Python. You don't need all the extra 
functionality of lists, so why go to the time and effort of building a 
list?




-- 
Steven


From maymunbeyin at gmail.com  Fri Jul 24 15:23:58 2009
From: maymunbeyin at gmail.com (kk)
Date: Fri, 24 Jul 2009 12:23:58 -0700 (PDT)
Subject: How can I get the line number ?
References: <60183aee-c4e4-4200-8449-198fd2b08258@p23g2000vbl.googlegroups.com>
	<mailman.3675.1248461967.8015.python-list@python.org>
Message-ID: <3ce2fe1a-c769-4f92-b4b0-559229158297@33g2000vbe.googlegroups.com>

Maxim,

Thank you so much. I will try right now.


From fabiofz at gmail.com  Fri Jul 24 15:43:36 2009
From: fabiofz at gmail.com (Fabio Zadrozny)
Date: Fri, 24 Jul 2009 16:43:36 -0300
Subject: Eclipse Pydev update error ?
In-Reply-To: <1248463044.8697.50.camel@localhost.localdomain>
References: <1248463044.8697.50.camel@localhost.localdomain>
Message-ID: <cfb578b20907241243ld649df0gc19342c241810ec4@mail.gmail.com>

On Fri, Jul 24, 2009 at 4:17 PM, Linuxguy123<linuxguy123 at gmail.com> wrote:
> Does anyone know why this error is occurring in my Eclipse Pydev
> update ?
>
> An error occurred while collecting items to be installed
> ?No repository found containing:
> org.python.pydev/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.ast/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.core/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.debug/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.feature/org.eclipse.update.feature/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.help/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.jython/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.parser/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.refactoring/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.templates/osgi.bundle/1.4.7.2843
> ?No repository found containing:
> org.python.pydev.customizations/osgi.bundle/1.4.7.2843
>

This usually happens if there was some connection error during the
update. You can try other mirrors (see:
http://pydev.blogspot.com/2009/07/pydev-147-released.html for the new
added mirrors).

Cheers,

Fabio


From tjreedy at udel.edu  Fri Jul 24 15:45:36 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 15:45:36 -0400
Subject: ElementTree's Element substitution in Python 3
In-Reply-To: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
Message-ID: <h4d311$qkd$1@ger.gmane.org>

Andr? wrote:
> I have a function to replace the content of an ElementTree Element by
> that of another one which works using Python 2 but not with Python 3.
> I get an assertion error.  The function is as follows:
> 
> def replace_element(elem, replacement):
>     '''replace the content of an ElementTree Element by that of
> another
>        one.
>     '''
>     elem.clear()
>     elem.text = replacement.text
>     elem.tail = replacement.tail
>     elem.tag = replacement.tag
>     elem.attrib = replacement.attrib
>     elem[:] = replacement[:]
> 
> The last line is problematic.  For example, if I do the following
> program with Python2.5
> ###
> from xml.etree import ElementTree as et
> 
> a = et.Element('a')
> b = et.SubElement(a, 'b')
> c = et.Element('c')
> 
> a[:] = c[:]
> ###
> nothing of note happens - however, doing the same with Python 3.1, I
> get the following traceback:
> 
> Traceback (most recent call last):
>   File "test.py", line 7, in <module>
>     a[:] = c[:]
>   File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
> 210, in __setitem__
>     assert iselement(element)
> AssertionError
> 
> ======
> I would gladly welcome any suggestion for writing a replace_element()
> function that works with Python 3.1

My guess is that you found a subtle bug in the 3.1 version of 
ElementTree, perhap a result of conversion. I would take a look at the 
noted line 210 to see whether it is 'a' or 'c' that is not passing as an 
element. Assuming that it is 'c', I would look at __getitem__ to see why 
not. Is [:] special-cased? Compare the codes for 2.5 and 3.1. Assuming 
it still looks like a bug, report it on the tracker using your minimal 
example, leaving out your function.

tjr



From tjreedy at udel.edu  Fri Jul 24 15:47:36 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 15:47:36 -0400
Subject: exceptions.TypeError an integer is required
In-Reply-To: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
Message-ID: <h4d34n$qkd$2@ger.gmane.org>

jakecjacobson wrote:
> I am trying to do a post to a REST API over HTTPS and requires the
> script to pass a cert to the server.  I am getting
> "exceptions.TypeError an integer is required" error and can't find the
> reason.  I commenting out the lines of code, it is happening on the
> connection.request() line.  Here is the problem code.  Would love some
> help if possible.
> 
> 	head = {"Content-Type" : "application/x-www-form-urlencoded",
> "Accept" : "text/plain"}
> 	parameters = urlencode({"collection" : collection, "entryxml" : open
> (file,'r').read()})
> 	try:
> 		connection = httplib.HTTPSConnection(host, port, key_file,
> cert_file)
> 		connection.request('POST', path, parameters, head)
> 		response = connection.getresponse()
> 		print response.status, response.reason
> 	except:
> 		print sys.exc_type, sys.exc_value
> 
> 	connection.close()

Help us help you by posting the full actual traceback.



From andre.roberge at gmail.com  Fri Jul 24 15:48:02 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Fri, 24 Jul 2009 12:48:02 -0700 (PDT)
Subject: ElementTree's Element substitution in Python 3
References: <72c9fbf8-88a0-4d62-86fa-44e450ef7272@k1g2000yqf.googlegroups.com>
	<m2d47phow9.fsf@cs.uu.nl>
Message-ID: <7ea510e0-ceb8-4425-9af2-b30154ad6e6d@b14g2000yqd.googlegroups.com>

On Jul 24, 4:17?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Andr? <andre.robe... at gmail.com> (A) a ?crit:
> >A> I have a function to replace the content of an ElementTree Element by
> >A> that of another one which works using Python 2 but not with Python 3.
> >A> I get an assertion error.

[SNIP]

> >A> Traceback (most recent call last):
> >A> ? File "test.py", line 7, in <module>
> >A> ? ? a[:] = c[:]
> >A> ? File "/usr/local/py3.1/lib/python3.1/xml/etree/ElementTree.py", line
> >A> 210, in __setitem__
> >A> ? ? assert iselement(element)
> >A> AssertionError
>
> This is a Python bug. Please report it.

Done.

> The problem is that in Python 3
> slice assignments are done with __setitem__ rather than __setslice__ but
> ElementTree has not been adapted to that.
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org



From linuxguy123 at gmail.com  Fri Jul 24 15:57:40 2009
From: linuxguy123 at gmail.com (Linuxguy123)
Date: Fri, 24 Jul 2009 13:57:40 -0600
Subject: Eclipse Pydev update error ?
In-Reply-To: <cfb578b20907241243ld649df0gc19342c241810ec4@mail.gmail.com>
References: <1248463044.8697.50.camel@localhost.localdomain>
	<cfb578b20907241243ld649df0gc19342c241810ec4@mail.gmail.com>
Message-ID: <1248465460.8697.51.camel@localhost.localdomain>

On Fri, 2009-07-24 at 16:43 -0300, Fabio Zadrozny wrote:
> On Fri, Jul 24, 2009 at 4:17 PM, Linuxguy123<linuxguy123 at gmail.com> wrote:
> > Does anyone know why this error is occurring in my Eclipse Pydev
> > update ?
> >
> > An error occurred while collecting items to be installed
> >  No repository found containing:
> > org.python.pydev/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.ast/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.core/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.debug/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.feature/org.eclipse.update.feature/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.help/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.jython/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.parser/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.refactoring/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.templates/osgi.bundle/1.4.7.2843
> >  No repository found containing:
> > org.python.pydev.customizations/osgi.bundle/1.4.7.2843
> >
> 
> This usually happens if there was some connection error during the
> update. You can try other mirrors (see:
> http://pydev.blogspot.com/2009/07/pydev-147-released.html for the new
> added mirrors).

Excellent reply.  Thanks.

I added http://fabioz.com/pydev/updates to my site list and the update
completed immediately.

I'll bookmark the blog as well.

Thanks again.




From clp2 at rebertia.com  Fri Jul 24 16:02:24 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 13:02:24 -0700
Subject: len() should always return something
In-Reply-To: <0279f6df$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <50697b2c0907241302m166d0c61y4912a29aaa4caaf1@mail.gmail.com>

On Fri, Jul 24, 2009 at 12:05 PM, Steven
D'Aprano<steve at remove-this-cybersource.com.au> wrote:
> On Fri, 24 Jul 2009 00:02:28 -0700, Chris Rebert wrote:
>
>> On Thu, Jul 23, 2009 at 11:35 PM, Dr. Phillip M.
>> Feldman<pfeldman at verizon.net> wrote:
>>>
>>> Some aspects of the Python design are remarkably clever, while others
>>> leave me perplexed. Here's an example of the latter: Why does len()
>>> give an error when applied to an int or float? len() should always
>>> return something; in particular, when applied to a scalar, it should
>>> return a value of 1. Of course, I can define my own function like this:
>>>
>>> def mylen(x):
>>> ? if isinstance(x,int) or isinstance(x,float): return 1 return len(x)
>>>
>>> But, this shouldn't be necessary.
>>
>> The problem is that redefining len()/length/size that way would violate
>> several principles of Python's design (The "Zen" of Python -
>> http://www.python.org/dev/peps/pep-0020/).
>>
>> Specifically:
>> - Explicit is better than implicit.
>> - Special cases aren't special enough to break the rules.
>> - Errors should never pass silently.
>> - In the face of ambiguity, refuse the temptation to guess.
>
>
> Chris, I'm curious why you think that these Zen are relevant to the OP's
> complaint.

To explain in more detail:

> Re explicit vs implicit, len(42) is just as explicit as len([42, 23]).

If you want a collection (something that has length), then one should
explicitly create one, not implicitly have a singleton value act like
it's a pseudo-collection.
I admit I'm somewhat conflating this principle with the anti-ambiguity
principle, but the two are related, imho.

> Arguably (I wouldn't argue this, but some people might) ints aren't
> "special enough" to break the rule that len(obj) should always return
> something.

Except that's not the current rule. The current rule is that it's
defined only for collections.
One would instead have to argue why ints are special enough to have
len() defined despite not being collections.
I think the point made by Grant Edwards is instructive. len(x) = 1
typically implies list(x)[0] and similar should be valid. Altering the
behavior would invalidate that theorem and cause quite a bit of code
upheaval, all just to save the OP from typing one pair of []s.

> (I don't actually agree, but some people might be able to produce a
> coherent argument why len() should apply equally to all objects.)

Well, yes, this /whole/ "argument" is entirely academic; the behavior
is extremely unlikely to change, we're just trying to give ex post
facto rationales for pedagogical purposes. :)

> Re errors passing silently, the OP doesn't believe that len(42) should be
> an error, so that's not relevant.

True, it would not directly silence an error, but defining len() on
scalars would tend towards obscuring errors in code that incorrectly
treats scalars as collections.

> And there's nothing ambiguous about len(42).

Really? What is its value then? I think arguments of varying quality
can be made for:
1 - as the OP and those from array programming languages would suggest
2 - the number of decimal digits in 42, if one was feeling Perlish
6 - the minimum number of bits necessary to represent 42 in binary
32 (or 64, depending on your CPU) - the number of bits necessary to
represent an int (obviously breaks down a bit with arbitrary-magnitude
ints)
undefined - i.e. it causes an error, the current behavior; asking for
the length of a non-collection is "nonsensical" or "absurd"

> I agree with the current Python behaviour, but I don't think there's
> anything in the Zen to support it. As far as I know, there is no

The problem and strength of the Zen is that it's all about how you
interpret it. :-)

Cheers,
Chris
-- 
http://blog.rebertia.com


From marcusw at cox.net  Fri Jul 24 16:09:15 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 24 Jul 2009 16:09:15 -0400
Subject: len() should always return something
In-Reply-To: <roy-B8E460.15045524072009@news.panix.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
	<roy-B8E460.15045524072009@news.panix.com>
Message-ID: <h4d4dc$jav$1@adenine.netfront.net>

On 7/24/2009 3:04 PM, Roy Smith wrote:
> In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
>  Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
> 
>> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
>>
>>>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
>>> and len("7") must return 8, by the same token... but wait!
>>>
>>>  >>> len("7")
>>> 1
>>>  >>>
>>>  >>>
>>> my python installation must me outdated ;-)
>> No no no, you're obviously using an awesome version of Python that can 
>> compress single-character strings to a single bit!
> 
> Compressing strings to a single bit is easy.  It's the uncompressing that's 
> tricky.
I assume you mean ord("7")%2?

First one to correctly decompress the value 0 into an ASCII character 
wins the title of the world's most capable hacker :p

Marcus


From breamoreboy at yahoo.co.uk  Fri Jul 24 16:18:26 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 24 Jul 2009 21:18:26 +0100
Subject: len() should always return something
In-Reply-To: <h4d4dc$jav$1@adenine.netfront.net>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>	<mailman.3661.1248444714.8015.python-list@python.org>	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>	<0279f596$0$5185$c3e8da3@news.astraweb.com>	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
Message-ID: <h4d4ti$ug$1@ger.gmane.org>

Marcus Wanner wrote:
> On 7/24/2009 3:04 PM, Roy Smith wrote:
>> In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
>>  Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
>>
>>> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
>>>
>>>>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
>>>> and len("7") must return 8, by the same token... but wait!
>>>>
>>>>  >>> len("7")
>>>> 1
>>>>  >>>
>>>>  >>>
>>>> my python installation must me outdated ;-)
>>> No no no, you're obviously using an awesome version of Python that 
>>> can compress single-character strings to a single bit!
>>
>> Compressing strings to a single bit is easy.  It's the uncompressing 
>> that's tricky.
> I assume you mean ord("7")%2?
> 
> First one to correctly decompress the value 0 into an ASCII character 
> wins the title of the world's most capable hacker :p
> 
> Marcus
asciichar = chr(len(0)) if the OP's wishes come true?

-- 
Kindest regards.

Mark Lawrence.



From marcusw at cox.net  Fri Jul 24 16:25:57 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 24 Jul 2009 16:25:57 -0400
Subject: len() should always return something
In-Reply-To: <mailman.3684.1248466691.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>	<mailman.3661.1248444714.8015.python-list@python.org>	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>	<0279f596$0$5185$c3e8da3@news.astraweb.com>	<roy-B8E460.15045524072009@news.panix.com>	<h4d4dc$jav$1@adenine.netfront.net>
	<mailman.3684.1248466691.8015.python-list@python.org>
Message-ID: <h4d5cm$jav$2@adenine.netfront.net>

On 7/24/2009 4:18 PM, Mark Lawrence wrote:
> Marcus Wanner wrote:
>> On 7/24/2009 3:04 PM, Roy Smith wrote:
>>> In article <0279f596$0$5185$c3e8da3 at news.astraweb.com>,
>>>  Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> wrote:
>>>
>>>> On Fri, 24 Jul 2009 16:50:03 +0200, superpollo wrote:
>>>>
>>>>>> Nah.  7 contains three bits, so len(7) should *clearly* return 3.
>>>>> and len("7") must return 8, by the same token... but wait!
>>>>>
>>>>>  >>> len("7")
>>>>> 1
>>>>>  >>>
>>>>>  >>>
>>>>> my python installation must me outdated ;-)
>>>> No no no, you're obviously using an awesome version of Python that 
>>>> can compress single-character strings to a single bit!
>>>
>>> Compressing strings to a single bit is easy.  It's the uncompressing 
>>> that's tricky.
>> I assume you mean ord("7")%2?
>>
>> First one to correctly decompress the value 0 into an ASCII character 
>> wins the title of the world's most capable hacker :p
>>
>> Marcus
> asciichar = chr(len(0)) if the OP's wishes come true?
> 
Nope, wasn't "?"...

Marcus


From python.list at tim.thechases.com  Fri Jul 24 16:30:10 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 24 Jul 2009 15:30:10 -0500
Subject: len() should always return something
In-Reply-To: <h4d4dc$jav$1@adenine.netfront.net>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>	<mailman.3661.1248444714.8015.python-list@python.org>	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>	<0279f596$0$5185$c3e8da3@news.astraweb.com>	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
Message-ID: <4A6A19D2.2020204@tim.thechases.com>

Marcus Wanner wrote:
> First one to correctly decompress the value 0 into an ASCII
> character wins the title of the world's most capable hacker :p

Bah...uncompressing the value 0 into *an* ASCII character is 
easy.  Uncompressing it into the *original* ASCII character from 
which it was compressed (with the aforementioned compression 
method) becomes a bit trickier ;-)

-tkc





From clp2 at rebertia.com  Fri Jul 24 16:34:11 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 13:34:11 -0700
Subject: len() should always return something
In-Reply-To: <4A6A19D2.2020204@tim.thechases.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
	<4a69ca1d$0$6161$4fafbaef@reader5.news.tin.it>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
	<4A6A19D2.2020204@tim.thechases.com>
Message-ID: <50697b2c0907241334t660fce21l3ae20e7772561cef@mail.gmail.com>

On Fri, Jul 24, 2009 at 1:30 PM, Tim Chase<python.list at tim.thechases.com> wrote:
> Marcus Wanner wrote:
>>
>> First one to correctly decompress the value 0 into an ASCII
>> character wins the title of the world's most capable hacker :p
>
> Bah...uncompressing the value 0 into *an* ASCII character is easy.
> ?Uncompressing it into the *original* ASCII character from which it was
> compressed (with the aforementioned compression method) becomes a bit
> trickier ;-)

Deja vu: http://www.hackles.org/cgi-bin/archives.pl?request=310

- Chris
-- 
http://blog.rebertia.com


From tismer at stackless.com  Fri Jul 24 16:39:36 2009
From: tismer at stackless.com (Christian Tismer)
Date: Fri, 24 Jul 2009 13:39:36 -0700
Subject: ANN: psyco V2
In-Reply-To: <4a696af3$0$442$426a74cc@news.free.fr>
References: <mailman.3252.1247798900.8015.python-list@python.org>	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>	<mailman.3613.1248368814.8015.python-list@python.org>
	<4a696af3$0$442$426a74cc@news.free.fr>
Message-ID: <4A6A1C08.6000202@stackless.com>

On 7/24/09 1:04 AM, William Dode wrote:
> On 23-07-2009, Christian Tismer wrote:
...

>> Wasn't the project plan saying the opposite, borrowing
>> some ideas from psyco? :-)
>> http://code.google.com/p/unladen-swallow/wiki/ProjectPlan
>
> How do you see the future of psyco when unladen-swallow will grab the
> best of psyco (if they can !) ?

I have no objections, but also no idea so far how that could work.
Sounded like an unreflected idea to me, without seriously
checking the possibilities and/or implications. The same
kind of research apparently did not happen concerning PyPy,
which IMHO is much more suitable to take advantage from.

This is for the current status of psyco, of course.
It will change dramatically in the next months, slowly
adopting some of PyPy's ideas. Then it might start to
make more sense.

> Wait and see ?

Wait and see, not holding breath, I'd say.

> Anyway, thanks a lot for your work that we can use NOW !

Thanks for so much encouraging reactions!

cheers - chris
-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
tismerysoft GmbH             :     Have a break! Take a ride on Python's
Johannes-Niemeyer-Weg 9A     :    *Starship* http://starship.python.net/
14109 Berlin                 :     PGP key -> http://wwwkeys.pgp.net/
work +49 30 802 86 56  mobile +49 173 24 18 776  fax +49 30 80 90 57 05
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/


From tjreedy at udel.edu  Fri Jul 24 16:43:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 16:43:17 -0400
Subject: list vs. tuple [Re: len() should always return something]
In-Reply-To: <0279f9e9$0$5185$c3e8da3@news.astraweb.com>
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>	<mailman.3674.1248461573.8015.python-list@python.org>	<roy-89AEB3.15032824072009@news.panix.com>
	<0279f9e9$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4d6d5$5gs$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 24 Jul 2009 15:03:29 -0400, Roy Smith wrote:
> 
>> In article <mailman.3674.1248461573.8015.python-list at python.org>,
>>  Terry Reedy <tjreedy at udel.edu> wrote:
>>
>>> Better:    if isinstance(x, (int, float, complex)):
>> I never noticed this before, but it seems odd that the second argument
>> to isinstance() should be a tuple.  Using the normal arguments made
>> about tuples vs. lists, it seems like a list would be the right data
>> structure here.

I ignore the 'normal arguments' and it seems that Guido or the designer 
of isinstance did so here too.  Fortunately.  Practicality beats 
'purity', especially misguided purity.

> What would be the point of using a list? You're never going to sort it, 
> or append items to it, or otherwise mutate it. You build it, pass it to a 
> function which doesn't modify it in any fashion, then it gets garbage 
> collected.
> 
> 
>> I suppose a set would be even more right, but (I'm
>> pretty sure) isinstance() predates sets.
> 
> Yes.
> 
> [steve at sylar ~]$ python1.5
> Python 1.5.2 (#1, Apr  1 2009, 22:55:54)  [GCC 4.1.2 20070925 (Red Hat 
> 4.1.2-27)] on linux2
> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>> isinstance
> <built-in function isinstance>
>>>> set
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
> NameError: set
> 
> 
> 
>> I'm curious why a tuple was chosen.
> 
> Tuples are smaller and faster to build than lists -- they're the most 
> lightweight sequence type in Python. You don't need all the extra 
> functionality of lists, so why go to the time and effort of building a 
> list?

In fact, constant tuples can be and now are compiled as constants:

 >>> dis(compile('(1,2,3)','','eval'))
   1           0 LOAD_CONST               3 ((1, 2, 3))
               3 RETURN_VALUE
 >>> dis(compile('[1,2,3]','','eval'))
   1           0 LOAD_CONST               0 (1)
               3 LOAD_CONST               1 (2)
               6 LOAD_CONST               2 (3)
               9 BUILD_LIST               3
              12 RETURN_VALUE

Internally, even a frozenset is more complicated than a tuple since it 
still needs a hash table, which is overkill for something that will be 
linearly scanned exactly once.

tjr



From qauzzix at gmail.com  Fri Jul 24 16:52:47 2009
From: qauzzix at gmail.com (Qauzzix)
Date: Fri, 24 Jul 2009 13:52:47 -0700 (PDT)
Subject: How do I generate dia diagrams from python source code?
Message-ID: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>

Greetings.

Since I have been using dia to make my UML diagrams. I also found an
util named dia2code that generates python code from dia diagram. Now
that I have that option I really want to find a way to generate dia
diagram from existing code and/or maintain my diagrams.

I have been googling  like crazy trying to find a way but with no
luck. Anyone here know how to do this?

Peace,
 - Jakob Sv. Bjarnason


From tjreedy at udel.edu  Fri Jul 24 16:52:53 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 16:52:53 -0400
Subject: len() should always return something
In-Reply-To: <50697b2c0907241302m166d0c61y4912a29aaa4caaf1@mail.gmail.com>
References: <24639361.post@talk.nabble.com>	<mailman.3645.1248418956.8015.python-list@python.org>	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<50697b2c0907241302m166d0c61y4912a29aaa4caaf1@mail.gmail.com>
Message-ID: <h4d6v5$75q$1@ger.gmane.org>

Chris Rebert wrote:

> I think the point made by Grant Edwards is instructive. len(x) = 1
> typically implies list(x)[0] and similar should be valid. 

At least, one should be able to iterate with x and get len(x) items.
See below.

>> And there's nothing ambiguous about len(42).
> 
> Really? What is its value then? I think arguments of varying quality
> can be made for:
> 1 - as the OP and those from array programming languages would suggest
> 2 - the number of decimal digits in 42, if one was feeling Perlish
> 6 - the minimum number of bits necessary to represent 42 in binary
> 32 (or 64, depending on your CPU) - the number of bits necessary to
> represent an int (obviously breaks down a bit with arbitrary-magnitude
> ints)
> undefined - i.e. it causes an error, the current behavior; asking for
> the length of a non-collection is "nonsensical" or "absurd"

In set theory, one can define counts recursively as follows
0 = {} (set, not dict)
n+1 = n | {n}
so len(n) = n, and in particular, len(42) = 42.

On the same basis, it has been proposed (and rejected) that iter(n) == 
range(n), do that we could write 'for i in 10' for instance. Guido 
thought this too esoteric.

Terry Jan Reedy



From tjreedy at udel.edu  Fri Jul 24 16:57:13 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 24 Jul 2009 16:57:13 -0400
Subject: non-owning references?
In-Reply-To: <0279f5b9$0$5185$c3e8da3@news.astraweb.com>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<0279f5b9$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4d779$7u4$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Fri, 24 Jul 2009 15:55:45 +0200, Hrvoje Niksic wrote:
> 
>> The term "variable" is used in the Python
>> language reference and elsewhere, and is quite compatible with how other
>> popular languages (Java, PHP, Lisp, ...) use it.  Please stop
>> complaining about valid terminology; it is not helpful.
> 
> No, the use of the single term "variable" to describe two distinct 
> program models is not helpful. Whether other languages muddy the water 
> between memory-location based variables and name-binding is irrelevant to 
> whether we should do so. And quite a few of us are disappointed that the 
> Python language reference should confuse the issue by using misleading 
> terminology.
> 
> Unfortunately, the use of "variable" is so ingrained, and so simple 
> compared to name binding terminology, that I fear we'll never eradicate 
> it. I know sometimes I use it myself, but always with a little shiver of 
> shame that I'm misusing terminology.

Some years ago, I read a claim that 'variable' has about 15 shades of 
meaning in math (some referring to non-variable constants), making it 
probably the most overloaded term in math. I am trying to mostly avoid 
it in the book I am writing.

tjr




From bryanvick at gmail.com  Fri Jul 24 17:11:02 2009
From: bryanvick at gmail.com (Bryan)
Date: Fri, 24 Jul 2009 14:11:02 -0700 (PDT)
Subject: Script runs manually, but cron fails
Message-ID: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>

I have a backup script that runs fine when I run it manually from the
command line.  When I run it with cron, the script stops running at
random points in the source code.

The script calls rsync with the subprocess module, which in turn uses
ssh to backup files from a box on my lan.  It also uses the atexit
module to always run a certain piece of cleanup code when the script
exits.  However, this piece of code is never called when I use cron to
run the script, but a ps -A command also does not show the python
process so I know the script is dead.  The log files generated by the
script all show rsync as completing, but then the logging gets cutoff
at random places when the script dies after that point.  I am not
getting any email from cron complaining of an error either.

The script runs fine in my bash shell, what could cron be doing to
interfere?





From duncan.booth at invalid.invalid  Fri Jul 24 17:14:06 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 24 Jul 2009 21:14:06 GMT
Subject: list vs. tuple [Re: len() should always return something]
References: <1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<mailman.3674.1248461573.8015.python-list@python.org>
	<roy-89AEB3.15032824072009@news.panix.com>
Message-ID: <Xns9C52E231DF188duncanbooth@127.0.0.1>

Roy Smith <roy at panix.com> wrote:

> In article <mailman.3674.1248461573.8015.python-list at python.org>,
>  Terry Reedy <tjreedy at udel.edu> wrote:
> 
>> Better:    if isinstance(x, (int, float, complex)):
> 
> I never noticed this before, but it seems odd that the second argument
> to isinstance() should be a tuple.  Using the normal arguments made
> about tuples vs. lists, it seems like a list would be the right data
> structure here.  I suppose a set would be even more right, but (I'm
> pretty sure) isinstance() predates sets.
> 
> I'm curious why a tuple was chosen.

There's a very good reason[*]. The second argument to isinstance() is a 
classinfo where a classinfo is a type or a tuple of classinfo.

That means you can have an arbitrarily complex set of nested tuples e.g. 
(int, (float, complex)), but the immutable nature of tuples means the 
implementation of isinstance can walk the tuple tree without ever having to 
worry about infinite loops.

If classinfo could be a list of types then someone somewhere would feed it 
a recursive list and then complain that the interpreter crashed.

Exception specifications are tuples for the same reason.

[*] For some definition of 'very good'. Would Python be significantly 
impaired if you couldn't combine classinfos into a tree structure? Probably 
not.


From anonymous.c.lisper at gmail.com  Fri Jul 24 17:58:57 2009
From: anonymous.c.lisper at gmail.com (ACL)
Date: Fri, 24 Jul 2009 14:58:57 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
Message-ID: <12ce2d31-5028-4b60-a5b1-5d5bf1fc06d7@f20g2000prn.googlegroups.com>

On Jul 24, 2:06?pm, Raffael Cavallaro
<raffaelcavall... at pas.espam.s.il.vous.plait.mac.com> wrote:
> On 2009-07-23 23:51:02 -0400, Carl Banks <pavlovevide... at gmail.com> said:
>
> > On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
> >> fft1976 wrote:
> >>> How do you explain that something as inferior as Python beat Lisp in
> >>> the market place despite starting 40 years later.
>
> >> Probably due to similar reasons that lead php to become remotely relevant
> > .
>
> > Well, the only reason PHP became relevant because it was an
> > easy
>
> ^^^^^^^^
> ^^^^^^^^ (emphasis added)
>
> > to
> > deploy solution in a single application domain, the web, that happened
> > to explode.
>
> i.e., Python "beat" lisp because it is ~70% of lisp in a form that is
> much more palatable to the average programmer, just as php became
> popular because it is powerful enough to do websites and, most
> importantly, apprehensible to mediocre programmers and even some
> non-programmers.
>
> --
> Raffael Cavallaro

I actually think that the thing holding lisp back is 'bus factor'.

Lets assume I have a java project and a lisp project:

Java project:
I have maybe 10 or 12 people on my team working on various subsystems
of my project. There are probably one or two 'technical leader' types
in the group, and a bunch of others who are sort of 'serfs', banging
out java classes. Lets say one of my important guys gets totally
splattered by a bus... I've still got another one left! I can rely on
the other guy to keep things afloat while I train up a new leader
type.

Lisp project:
I don't need as many people. I have 3 or 4 people, and one person is
my technical leader and lisp guru. Guru is probably in charge of more
difficult macros and (because of that), also in charge of the overall
design (macros are design patterns embodied in code). Lets say he gets
totally annihilated by the bus. What do I do now? I had all my eggs in
one basket and my project is now stalled.

I think that (for example) when people are saying that lisp macros
make projects difficult to understand, or that lisp hackers are much
harder to find than other programmers, what they are really showing is
that because of the nature of the language, lisp projects get
organized in a different way. This different way of organization is
especially hard on corporate projects, because managers are expected
to plan for when some important guy drops dead.

The problem with lisp is that if you hire too many extra hackers, you
end up with a bunch of people sitting around twiddling their thumbs.

This may also explain why it gets touted as an academic language. In
academia if a professor who is leading some important research drops
dead, who cares? Most likely no one had interest as to whether the
university would make a profit on this particular research endeavor
(except maybe the deceased, as he would like to get grant funding).

So I guess then we can give some tips for making lisp more acceptable
for 'paying gigs'.
1.) If you are a lisp hacker, it is your duty to be lazier and write
less code. We need to make it so that these projects need sizable
teams of people to complete.

2.) Write down everything that you do, everything you are going to do.
Maybe draw some object diagrams of your important/fancy macros, make
sure these are stored with the source. (You'll note that an iterative
approach to programming isn't really conducive to making a lot of
diagrams of stuff...)

I don't know what this has to do with python or scheme or people
dumping scheme for python.
Honestly, I seriously doubt that any undergraduate programming course
will give you enough actual programming experience to make you
seriously proficient in the language (research projects not counted).
The language used to teach the material is a cursory detail.


From user at example.net  Fri Jul 24 18:28:09 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 00:28:09 +0200
Subject: pack an integer into a string
Message-ID: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>

is there a pythonic and synthetic way (maybe some standard module) to 
"pack" an integer (maybe a *VERY* big one) into a string? like this:

  >>> number = 252509952
  >>> hex(number)
  '0xf0cff00'
  >>>

so i would like a string like '\xf0\xcf\xf0\x00'

i wrote some code to do it, so ugly i am ashamed to post :-(

i tried xdrlib, but does not quite do what i mean...

bye


From martin at v.loewis.de  Fri Jul 24 18:28:24 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sat, 25 Jul 2009 00:28:24 +0200
Subject: installing 2.6 on vista64
In-Reply-To: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
References: <ed0a1de8-03aa-4850-ad10-6f34797595ed@a39g2000pre.googlegroups.com>
Message-ID: <4a6a3588$0$11346$9b622d9e@news.freenet.de>

> I just downloaded and attempted to install python 2.6.2.  The
> installer proceeds to do its work then dies, leaving an entry in the
> eventlog:
> 
> Windows Installer installed the product. Product Name: Python 2.6.2.
> Product Version: 2.6.2150. Product Language: 1033. Installation
> success or error status: 1602.

Are you using subst'ed drives by any chance?

> Googling for this I wasn't able to narrow the results down to
> something usable. Anyone know of issues and how to fix them installing
> on vista 64 (yes, I have 8 gigs of ram)

Run "msiexec /i <pythonxy.msi> /l*v python.log", and search the log file
for 1602. This should give a clue.

Regards,
Martin


From emile at fenx.com  Fri Jul 24 18:41:59 2009
From: emile at fenx.com (Emile van Sebille)
Date: Fri, 24 Jul 2009 15:41:59 -0700
Subject: Script runs manually, but cron fails
In-Reply-To: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
References: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
Message-ID: <h4ddfr$o4h$1@ger.gmane.org>

On 7/24/2009 2:11 PM Bryan said...
> The script runs fine in my bash shell, what could cron be doing to
> interfere?

It's likely environmental -- make sure you're starting with the same 
path, etc.  Sometimes I'll create a sell script by env'ing to a bash 
script file and append the actual command to execute, chmod a+x the 
script and put that in the cron file.  Then strip out variables until 
you find the missing culprit.

HTH,

Emile





From sbassi at clubdelarazon.org  Fri Jul 24 18:43:58 2009
From: sbassi at clubdelarazon.org (Sebastian Bassi)
Date: Fri, 24 Jul 2009 19:43:58 -0300
Subject: pack an integer into a string
In-Reply-To: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <9e2f512b0907241543o5b4606agf80a87af74b4116@mail.gmail.com>

On Fri, Jul 24, 2009 at 7:28 PM, superpollo<user at example.net> wrote:
> is there a pythonic and synthetic way (maybe some standard module) to "pack"
> an integer (maybe a *VERY* big one) into a string? like this:

What do you mean to pack? Maybe Pickle is what you want.

import cPickle
variable = 124348654333577698
cPickle.dump(variable,open('filename', 'w'))

To load it:

import cPickle
vaariable = cPickle.load(open('filename'))

It is not "into a string", but instead of a filename, use a string with stringio


From 9372966370 at sms.mycricket.com  Fri Jul 24 18:51:49 2009
From: 9372966370 at sms.mycricket.com (9372966370 at sms.mycricket.com)
Date: 24 Jul 09 16:51:49 -0600
Subject: No subject
Message-ID: <200907242251.n6OLv34O026362@mta2-den.mycricket.com>

(Re: urllib2.URLError: <urlopen error unknown url type: 'http> error using
	twill with python)  how can i change url/http://...
 ---------------------------------------------
Sent by a Cricket mobile device
 ---------------------------------------------


From 9372966370 at sms.mycricket.com  Fri Jul 24 18:53:15 2009
From: 9372966370 at sms.mycricket.com (9372966370 at sms.mycricket.com)
Date: 24 Jul 09 16:53:15 -0600
Subject: No subject
Message-ID: <200907242253.n6OLv34f026362@mta2-den.mycricket.com>

(Re: urllib2.URLError: <urlopen error unknown url type: 'http> error using
	twill with python)
 ---------------------------------------------
Sent by a Cricket mobile device
 ---------------------------------------------


From user at example.net  Fri Jul 24 18:58:07 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 00:58:07 +0200
Subject: pack an integer into a string
In-Reply-To: <mailman.3691.1248475441.8015.python-list@python.org>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
	<mailman.3691.1248475441.8015.python-list@python.org>
Message-ID: <4a6a3c82$0$6157$4fafbaef@reader5.news.tin.it>

Sebastian Bassi wrote:
> On Fri, Jul 24, 2009 at 7:28 PM, superpollo<user at example.net> wrote:
> 
>>is there a pythonic and synthetic way (maybe some standard module) to "pack"
>>an integer (maybe a *VERY* big one) into a string? like this:
> 
> 
> What do you mean to pack? Maybe Pickle is what you want.
> 
> import cPickle
> variable = 124348654333577698
> cPickle.dump(variable,open('filename', 'w'))
> 
> To load it:
> 
> import cPickle
> vaariable = cPickle.load(open('filename'))
> 
> It is not "into a string", but instead of a filename, use a string with stringio


  >>> number
  252509952
  >>> f = cStringIO.StringIO()
  >>> cPickle.dump(number , f)
  >>> f.getvalue()
  'I252509952\n.'
  >>>

as you can see, the pickled representation is not what i wanted...

thanks anyway

bye


From piet at cs.uu.nl  Fri Jul 24 19:03:25 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 01:03:25 +0200
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <m23a8lhef6.fsf@cs.uu.nl>

>>>>> superpollo <user at example.net> (s) wrote:

>s> is there a pythonic and synthetic way (maybe some standard module) to
>s> "pack" an integer (maybe a *VERY* big one) into a string? like this:

>>>>> number = 252509952
>>>>> hex(number)
>s>  '0xf0cff00'
>>>>> 

>s> so i would like a string like '\xf0\xcf\xf0\x00'

You have the string wrong.
But the correct one you get with:

In [67]: import struct

In [68]: number = 252509952

In [69]: struct.pack('>I', number)
Out[69]: '\x0f\x0c\xff\x00'

(Please note that this is big endian)
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From user at example.net  Fri Jul 24 19:11:08 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 01:11:08 +0200
Subject: pack an integer into a string
In-Reply-To: <4a6a3c82$0$6157$4fafbaef@reader5.news.tin.it>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
	<mailman.3691.1248475441.8015.python-list@python.org>
	<4a6a3c82$0$6157$4fafbaef@reader5.news.tin.it>
Message-ID: <4a6a3f8f$0$6157$4fafbaef@reader5.news.tin.it>

superpollo wrote:
> Sebastian Bassi wrote:
> 
>> On Fri, Jul 24, 2009 at 7:28 PM, superpollo<user at example.net> wrote:
>>
>>> is there a pythonic and synthetic way (maybe some standard module) to 
>>> "pack"
>>> an integer (maybe a *VERY* big one) into a string? like this:
>>
>>
>>
>> What do you mean to pack? Maybe Pickle is what you want.
>>
>> import cPickle
>> variable = 124348654333577698
>> cPickle.dump(variable,open('filename', 'w'))
>>
>> To load it:
>>
>> import cPickle
>> vaariable = cPickle.load(open('filename'))
>>
>> It is not "into a string", but instead of a filename, use a string 
>> with stringio
> 
> 
> 
>  >>> number
>  252509952
>  >>> f = cStringIO.StringIO()
>  >>> cPickle.dump(number , f)
>  >>> f.getvalue()
>  'I252509952\n.'
>  >>>
> 
> as you can see, the pickled representation is not what i wanted...
> 

OTOH, using a higher protocol:

  >>> cPickle.dump(number , f , 1)
  >>> f.getvalue()
  'J\x00\xff\x0c\x0f.'

which is very close to '\xf0\xcf\xf0\x00', that i meant originally... so 
i i change my spec as; '\x0f\x0c\xff\x00' (i.e. left- intead of right- 
zeropadding) i am almost there...

bye


From bartc at freeuk.com  Fri Jul 24 19:15:32 2009
From: bartc at freeuk.com (bartc)
Date: Fri, 24 Jul 2009 23:15:32 GMT
Subject: len() should always return something
In-Reply-To: <mailman.3644.1248417347.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <ogram.60449$OO7.20862@text.news.virginmedia.com>

"Dr. Phillip M. Feldman" <pfeldman at verizon.net> wrote in message 
news:mailman.3644.1248417347.8015.python-list at python.org...
>
> Some aspects of the Python design are remarkably clever, while others 
> leave
> me perplexed. Here's an example of the latter: Why does len() give an 
> error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1.

So you want len() to treat 123 as though it could potentially be a list 
containing a single element?

In that case there could be an ambiguity here:

print len([10,20,30])

Should it print 3 (the elements in [10,20,30]), or 1 (treating [10,20,30] as 
a potential list containing the single element [10,20,30])?

-- 
bartc 



From user at example.net  Fri Jul 24 19:16:07 2009
From: user at example.net (superpollo)
Date: Sat, 25 Jul 2009 01:16:07 +0200
Subject: pack an integer into a string
In-Reply-To: <m23a8lhef6.fsf@cs.uu.nl>
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
	<m23a8lhef6.fsf@cs.uu.nl>
Message-ID: <4a6a40ba$0$6157$4fafbaef@reader5.news.tin.it>

Piet van Oostrum wrote:
...
> You have the string wrong.

oops yea.

> But the correct one you get with:
> 
> In [67]: import struct
> 
> In [68]: number = 252509952
> 
> In [69]: struct.pack('>I', number)
> Out[69]: '\x0f\x0c\xff\x00'
>
> (Please note that this is big endian)

thanks a lot, but it does not work for large integers:

  >>> number
  283691163101781L
  >>> struct.pack('>I', number)
  Traceback (most recent call last):
    File "<stdin>", line 1, in ?
  OverflowError: long int too large to convert
  >>>

bye


From scriptlearner at gmail.com  Fri Jul 24 19:20:00 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Fri, 24 Jul 2009 16:20:00 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
Message-ID: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>

My parent thread keeps a counter for the number of free child workers
(say 100) and initializes some child threads and call child.start().
Once the number of free child workers reach 0, the parent thread will
wait until some at least one child thread finishes and then it will
initialize another child thread.
My question is, how can a child thread notify the parent that it's
done so that the parent can call join() on it?  I am not sure how a
child thread can send a signal to its parent while it may not even
know anything about it's parent.  Can you guys please provide some
suggestions?  Some code samples will be nice.  Thanks.


From greg at cosc.canterbury.ac.nz  Fri Jul 24 19:24:13 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sat, 25 Jul 2009 11:24:13 +1200
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
In-Reply-To: <861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<7cn54pF28nv72U1@mid.individual.net>
	<861f18de-ceb9-46d9-92f1-13a95dcf047e@h31g2000yqd.googlegroups.com>
Message-ID: <7cuu3eF29jmmuU2@mid.individual.net>

Bearophile wrote:

> Was this link, shown by William, not enough?
> http://hg.flibuste.net/libre/games/cheval/file/46797c3a5136/chevalx.pyx#l1

Yes, sorry, I posted too soon.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Fri Jul 24 19:26:44 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Sat, 25 Jul 2009 11:26:44 +1200
Subject: clean way prepend an element to a numpy array
In-Reply-To: <mailman.3554.1248291958.8015.python-list@python.org>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>	<7cnr5tF28183hU1@mid.individual.net>
	<mailman.3554.1248291958.8015.python-list@python.org>
Message-ID: <7cuu86F2945qmU1@mid.individual.net>

Robert Kern wrote:

>> a[:0] = array('i', [0])
> 
> Not when 'a' is a numpy array rather than an array.array.

That's true, but I got the impression that the OP was
talking about array.array, not numpy.array.

It's very confusing having two widely-used types
both called 'array'. :-(

-- 
Greg


From robert.kern at gmail.com  Fri Jul 24 19:35:01 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 24 Jul 2009 18:35:01 -0500
Subject: clean way prepend an element to a numpy array
In-Reply-To: <7cuu86F2945qmU1@mid.individual.net>
References: <493c4132-fb88-4fcc-9b1c-327f4dc3d905@l35g2000pra.googlegroups.com>	<7cnr5tF28183hU1@mid.individual.net>	<mailman.3554.1248291958.8015.python-list@python.org>
	<7cuu86F2945qmU1@mid.individual.net>
Message-ID: <h4dgf6$uhe$1@ger.gmane.org>

On 2009-07-24 18:26, greg wrote:
> Robert Kern wrote:
>
>>> a[:0] = array('i', [0])
>>
>> Not when 'a' is a numpy array rather than an array.array.
>
> That's true, but I got the impression that the OP was
> talking about array.array, not numpy.array.

Did you read the Subject: line? :-)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python at mrabarnett.plus.com  Fri Jul 24 19:44:36 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 25 Jul 2009 00:44:36 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
Message-ID: <4A6A4764.1080206@mrabarnett.plus.com>

scriptlearner at gmail.com wrote:
> My parent thread keeps a counter for the number of free child workers
> (say 100) and initializes some child threads and call child.start().
> Once the number of free child workers reach 0, the parent thread will
> wait until some at least one child thread finishes and then it will
> initialize another child thread.
> My question is, how can a child thread notify the parent that it's
> done so that the parent can call join() on it?  I am not sure how a
> child thread can send a signal to its parent while it may not even
> know anything about it's parent.  Can you guys please provide some
> suggestions?  Some code samples will be nice.  Thanks.

I would create a queue ("Queue" module) and pass it to each child; the 
child would put something (eg a reference to itself) in the queue when
it had finished.


From lists at cheimes.de  Fri Jul 24 19:53:19 2009
From: lists at cheimes.de (Christian Heimes)
Date: Sat, 25 Jul 2009 01:53:19 +0200
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
Message-ID: <h4dhhf$1g5$1@ger.gmane.org>

scriptlearner at gmail.com wrote:
> My parent thread keeps a counter for the number of free child workers
> (say 100) and initializes some child threads and call child.start().
> Once the number of free child workers reach 0, the parent thread will
> wait until some at least one child thread finishes and then it will
> initialize another child thread.
> My question is, how can a child thread notify the parent that it's
> done so that the parent can call join() on it?  I am not sure how a
> child thread can send a signal to its parent while it may not even
> know anything about it's parent.  Can you guys please provide some
> suggestions?  Some code samples will be nice.  Thanks.

You are using the wrong approach here. There is a much easier solution
to your problem although it's not obvious in the first place. In this
approach the worker threads don't have to notify the parent thread that
they are ready.

The main thread creates a queue and a bunch of worker threads that are
pulling tasks from the queue. As long as the queue is empty all worker
threads block and do nothing. When a task is put into the queue a random
worker thread acquires the task, does it job and sleeps as soon as its
ready. That way you can reuse a thread over and over again without
creating a new worker threads.

When you need to stop the threads you put a kill object into the queue
that tells the thread to shut down instead of blocking on the queue.

Christian



From python at mrabarnett.plus.com  Fri Jul 24 20:05:22 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 25 Jul 2009 01:05:22 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <h4dhhf$1g5$1@ger.gmane.org>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<h4dhhf$1g5$1@ger.gmane.org>
Message-ID: <4A6A4C42.40004@mrabarnett.plus.com>

Christian Heimes wrote:
> scriptlearner at gmail.com wrote:
>> My parent thread keeps a counter for the number of free child workers
>> (say 100) and initializes some child threads and call child.start().
>> Once the number of free child workers reach 0, the parent thread will
>> wait until some at least one child thread finishes and then it will
>> initialize another child thread.
>> My question is, how can a child thread notify the parent that it's
>> done so that the parent can call join() on it?  I am not sure how a
>> child thread can send a signal to its parent while it may not even
>> know anything about it's parent.  Can you guys please provide some
>> suggestions?  Some code samples will be nice.  Thanks.
> 
> You are using the wrong approach here. There is a much easier solution
> to your problem although it's not obvious in the first place. In this
> approach the worker threads don't have to notify the parent thread that
> they are ready.
> 
> The main thread creates a queue and a bunch of worker threads that are
> pulling tasks from the queue. As long as the queue is empty all worker
> threads block and do nothing. When a task is put into the queue a random
> worker thread acquires the task, does it job and sleeps as soon as its
> ready. That way you can reuse a thread over and over again without
> creating a new worker threads.
> 
> When you need to stop the threads you put a kill object into the queue
> that tells the thread to shut down instead of blocking on the queue.
> 
The extra trick is that when a thread gets the kill object it puts it
back before terminating so that another thread will also get it.


From googler.1.webmaster at spamgourmet.com  Fri Jul 24 20:12:13 2009
From: googler.1.webmaster at spamgourmet.com (moerchendiser2k3)
Date: Fri, 24 Jul 2009 17:12:13 -0700 (PDT)
Subject: Freetype2 in PIL
Message-ID: <95f321b4-d7e8-4515-8743-dad86298024d@a26g2000yqn.googlegroups.com>

Hi,

I have a problem with Freetype2 in the Python Image Library. I
compiled it as 64bit and I got a file named freetype239.lib. So I
added this file to a folder called lib. I added the parent folder of
the lib folder to the setup.py settings (like all the others: libjpeg,
zlib). LIbjpeg and Zlib works fine on Windows 64 bit and the installer
can find them.

But I just get a "Freetype2 not found". Even renaming it to
freetype.lib and freetype2.lib doesnt work.


Any suggestions why PIL cant find the library?

Bye and thanks in advance :)


From googler.1.webmaster at spamgourmet.com  Fri Jul 24 20:12:13 2009
From: googler.1.webmaster at spamgourmet.com (moerchendiser2k3)
Date: Fri, 24 Jul 2009 17:12:13 -0700 (PDT)
Subject: Freetype2 in PIL
Message-ID: <dff064ef-e6e9-46a0-9256-ef887336c246@y19g2000yqy.googlegroups.com>

Hi,

I have a problem with Freetype2 in the Python Image Library. I
compiled it as 64bit and I got a file named freetype239.lib. So I
added this file to a folder called lib. I added the parent folder of
the lib folder to the setup.py settings (like all the others: libjpeg,
zlib). LIbjpeg and Zlib works fine on Windows 64 bit and the installer
can find them.

But I just get a "Freetype2 not found". Even renaming it to
freetype.lib and freetype2.lib doesnt work.


Any suggestions why PIL cant find the library?

Bye and thanks in advance :)


From gallium.arsenide at gmail.com  Fri Jul 24 20:14:59 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Fri, 24 Jul 2009 17:14:59 -0700 (PDT)
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it> 
	<m23a8lhef6.fsf@cs.uu.nl>
	<4a6a40ba$0$6157$4fafbaef@reader5.news.tin.it>
Message-ID: <669833bd-7d70-4cec-a9a3-9de50d77d8e7@c14g2000yqm.googlegroups.com>

On Jul 24, 7:16?pm, superpollo <u... at example.net> wrote:
> thanks a lot, but [struct] does not work for large integers:

Since the struct module is designed specifically for C-style structs,
it's definitely not going to handle arbitrary-length integers on its
own.  You could chop up your Python (long) integer into C-sized pieces
and then pack the pieces; but if you need to do that, the advantage of
using struct at all may be minimal or even completely gone.

> OTOH, using a higher [pickle] protocol:

If you are sure you are going to keep using the same version of
Python, then this could work.  I would personally not depend on this
to keep working in future versions.

I'm not aware of any existing package that does what you want.  Maybe
someone else does.  How I personally would tackle your problem is to
write the whole thing from scratch (as you've done).

John


From deets at nospam.web.de  Fri Jul 24 20:33:11 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 25 Jul 2009 02:33:11 +0200
Subject: cgi.fieldstorage()
In-Reply-To: <f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
	<f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
Message-ID: <7cv268F29q0j5U1@mid.uni-berlin.de>

gert schrieb:
> On Jul 24, 7:32 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> gert schrieb:
>>
>>> this is a non standard way to store multi part post data on disk
>>> def application(environ, response):
>>>     with open('/usr/httpd/var/wsgiTemp','w') as f:
>>>         while True:
>>>             chunk = environ['wsgi.input'].read(8192).decode('latin1')
>>>             if not chunk: break
>>>             f.write(chunk)
>>>     response('200 OK',[])
>>>     return ['complete']
>>> my question is how do i handle the file, so i can shuffle it into a db
>>> using small chunks of memorie ?
>> I don't think that's possible with the current DB-API. There is no
>> stream-based BLOB-interface (as e.g. JDBC offers).
>>
>> So the answer certainly depends on your used RDBMS. For oracle, you
>> would be lucky:
>>
>> http://cx-oracle.sourceforge.net/html/lob.html
>>
>> Other adapters I don't know about.
> 
> sqlite :) ok let say for now it would be impossible on a db level, but
> before i reach the impossible, i still need to parse the file to
> prepare the chunks. How do i do that ? How do i get the chunks without
> loading the hole file into memorie ?

It's memory - memorie might be some nice dutch girl you know :)

Apart from that, your code above does exactly that - reads the data 
chunkwise. If the WSGI-implementation works proper, this will be the 
socket's input stream, so there is no memory overhead involved.

Now of course if you want to have a multi-pass processing of the file 
without putting it into memory, then you need to save it to the harddisk 
befor.

But honestly - we are talking about a web-application here. My 
DSL-connection has 1 MBit upstream, the average server has at least 2GB 
of memory available - so we are talking 20000 seconds uploading time to 
fill that memory. Which is about 5 hours. And you are decoding the data 
to a certain decoding, so we are not talking about binary data here - 
are you really sure memory is an issue?

Diez

Diez


From casevh at gmail.com  Fri Jul 24 20:35:59 2009
From: casevh at gmail.com (casevh)
Date: Fri, 24 Jul 2009 17:35:59 -0700 (PDT)
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <7728c70f-4d1d-4e5c-ae8b-175491fc1d31@f18g2000prf.googlegroups.com>

On Jul 24, 3:28?pm, superpollo <u... at example.net> wrote:
> is there a pythonic and synthetic way (maybe some standard module) to
> "pack" an integer (maybe a *VERY* big one) into a string? like this:
>
> ? >>> number = 252509952
> ? >>> hex(number)
> ? '0xf0cff00'
> ? >>>
>
> so i would like a string like '\xf0\xcf\xf0\x00'
>
> i wrote some code to do it, so ugly i am ashamed to post :-(
>
> i tried xdrlib, but does not quite do what i mean...
>
> bye

This works, I think.

>>> def hex_string(n):
...     a = hex(n)
...     ch_list = []
...     if a.startswith('0x'): a = a[2:]
...     if a.endswith('L'): a = a[:-1]
...     for i in range(0, len(a)):
...         ch_list.append(chr(int(a[i:i+2],16)))
...     return ''.join(ch_list)
...
>>> hex_string(252509952)
'\xf0\x0c\xcf\xff\xf0\x00\x00'
>>> hex_string(283691163101781L)
'\x10\x02 \x03?\xff\xf0\x00\n\xaa\xa5U\x05'
>>>


From deets at nospam.web.de  Fri Jul 24 20:38:28 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 25 Jul 2009 02:38:28 +0200
Subject: Computation/E-mail Expert opinions?
In-Reply-To: <9e520bf6-bc15-4942-a668-d18c2dbaf80f@o32g2000yqm.googlegroups.com>
References: <9e520bf6-bc15-4942-a668-d18c2dbaf80f@o32g2000yqm.googlegroups.com>
Message-ID: <7cv2g5F29q0j5U2@mid.uni-berlin.de>

scribio_vide schrieb:
> MAIL From: <tommyo2 at centrum.sk>
> From: "tommy02" <tommy02 at centrum.sk>
> To: "MeAmI" <MeAmI at vzw.blackberry.net>
> Subject: I AM LOOKING FORWARD TO YOUR ANSWER ON THIS ISSUE
> Date: Fri, 24 Jul 09 11:52:27 Pacific Daylight Time
> MIME-Version: 1.0
> Content-Type: multipart/mixed;boundary= "----
> =_NextPart_000_008C_8F228C8E.684AAFEA"
> X-Priority: 3
> X-MSMail-Priority: Normal
> X-Mailer: Microsoft Outlook Express 6.00.2462.0000
> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2462.0000
> 
> ------=_NextPart_000_008C_8F228C8E.684AAFEA
> Content-Type: text/plain
> Content-Transfer-Encoding: base64
> 

<snip/>

> ZXRtYWlsLmNvbQ0KICAgIA==
> ------=_NextPart_000_008C_8F228C8E.684AAFEA--
> 
> Any ides why I this came to be in my inbox?

It is either an extremely dangerous virus - or an utterly harmless, but 
annoying base64-encoded spam-mail, given the subject.

None of the possibilities justifies a post to *three* newsgroups.

Diez


From scriptlearner at gmail.com  Fri Jul 24 20:39:04 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Fri, 24 Jul 2009 17:39:04 -0700 (PDT)
Subject: time in milliseconds by calling time.time()
Message-ID: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>

I am trying to measure some system response time by using the time.time
() or time.clock() in my script.  However, the numbers I get are in
10s of milliseconds.
For example,
1248481670.34   #from time.time()
0.08                   #from time.clock()

That won't work for me, since the response time may be only a few
milliseconds.
My environment is Solaris 10 with Python 2.4.4 (#7, Feb  9 2007,
22:10:21).

SunOS 5.10 Generic_137112-07 i86pc i386 i86pc


The tricky thing is, if I run the python interpreter and import the
time module, I can get a time floating number in better precision by
calling time.time().  Do you guys have any suggestion on debugging
this problem?  Or, is there any other module I can try?  Thanks.

$ python
Python 2.4.4 (#7, Feb  9 2007, 22:10:21)
[GCC 3.4.6] on sunos5
Type "help", "copyright", "credits" or "license" for more information.
>>> import time
>>> time.time()
1248481930.8023829  <--I like this!
>>> time.clock()
0.0
>>>


From aahz at pythoncraft.com  Fri Jul 24 21:09:08 2009
From: aahz at pythoncraft.com (Aahz)
Date: 24 Jul 2009 18:09:08 -0700
Subject: Python ctypes on win64
References: <f415d834-b2ac-4036-afb1-a12c79480eb4@i6g2000yqj.googlegroups.com>
Message-ID: <h4dlvk$2is$1@panix3.panix.com>

In article <f415d834-b2ac-4036-afb1-a12c79480eb4 at i6g2000yqj.googlegroups.com>,
ulf  <wfluro at gmail.com> wrote:
>
>Does anybody know if python includes a win64 version of ctypes?
>
>According to the documentation it should be included - at least
>there's no special remarks for win64, and I haven't found any recent
>notes saying that it shouldn't work on win64. Yet it looks like both
>the installer from Python.org and from ActiveState.com have disabled
>it.

Nobody seems to have followed up to this, you may have better luck on
the capi-sig mailing list.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From rylesny at gmail.com  Fri Jul 24 21:11:29 2009
From: rylesny at gmail.com (ryles)
Date: Fri, 24 Jul 2009 18:11:29 -0700 (PDT)
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
Message-ID: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>

According to http://www.python.org/doc/essays/packages.html:

"The import statement first tests whether the item is defined in the
package; if not, it assumes it is a module and attempts to load it."

However, I've noticed that once a module is imported using the
`from pkg import mod' syntax, if its name is deleted from the
package namespace then subsequent imports with `from' will fail.

Here is an example of this type of scenario:

$ ls -l pkg
total 8.0K
-rw-rw-r-- 1 ? general   0 Jul 24 20:21 _impl.py
-rw-rw-r-- 1 ? general 147 Jul 24 20:28 __init__.py
-rw-rw-r-- 1 ? general   0 Jul 24 20:33 public2.py
-rw-rw-r-- 1 ? general 208 Jul 24 20:32 public.py

$ cat pkg/__init__.py
from pkg import _impl

# Add functions which refer to objects in _impl
# ...

# Don't "currently" require this in the namespace anymore.
del _impl

$ cat pkg/public.py
# Implement something with the aid of _impl.

from pkg import public2  # OK, fine.
from pkg import _impl    # The module exists, but this will fail.
# Could do import pkg._impl (or a relative import)

$ python
Python 2.6.2 (r262:71600, Jul 16 2009, 14:04:28)
[GCC 4.1.2 20071124 (Red Hat 4.1.2-42)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg import public
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pkg/public.py", line 4, in <module>
    from pkg import _impl    # The module exists, but this will fail.
ImportError: cannot import name _impl
>>> import sys
>>> sys.modules["pkg._impl"]
<module 'pkg._impl' from 'pkg/_impl.py'>
>>> from pkg import _impl
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: cannot import name _impl
>>> import pkg._impl  # Giving up!
>>>

I had previously noted that once a module is imported from a package
it is automatically added to the package namespace:

>>> import pkg
>>> dir(pkg)
['__builtins__', '__doc__', '__file__', '__name__', '__package__',
'__path__']
>>> from pkg import public2
>>> dir(pkg)
['__builtins__', '__doc__', '__file__', '__name__', '__package__',
'__path__', 'public2']
>>>

However, I didn't expect python to give up on importing those names
again
once removed.

Can anyone provide more details on what's occurring here?

Is this behavior intentional (a feature), or, is it in your opinion, a
defect?


From roy at panix.com  Fri Jul 24 21:27:10 2009
From: roy at panix.com (Roy Smith)
Date: Fri, 24 Jul 2009 21:27:10 -0400
Subject: time in milliseconds by calling time.time()
References: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>
Message-ID: <roy-7CF120.21271024072009@news.panix.com>

In article 
<9c600f0c-f4a0-4e8c-bbb9-27f128aecc50 at m7g2000prd.googlegroups.com>,
 "scriptlearner at gmail.com" <scriptlearner at gmail.com> wrote:

> I am trying to measure some system response time by using the time.time
> () or time.clock() in my script.  However, the numbers I get are in
> 10s of milliseconds.
> [...]
> The tricky thing is, if I run the python interpreter and import the
> time module, I can get a time floating number in better precision by
> calling time.time().
> [...]
> >>> time.time()
> 1248481930.8023829  <--I like this!

time.time() is returning a float in either case.  The difference you are 
seeing is purely related to how you are printing it; executing a "print" 
statement as opposed to the interactive interpreter printing a value.

Notice:

Roy-Smiths-MacBook-Pro:play$ python
Python 2.5.1 (r251:54863, Feb  6 2009, 19:02:12) 
[GCC 4.0.1 (Apple Inc. build 5465)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import time
>>> print time.time()
1248484949.75
>>> time.time()
1248484957.151274

and further notice:

>>> x = time.time()
>>> str(x)
'1248485028.58'
>>> repr(x)
'1248485028.5814769'

Keep in mind that while a float may have a large apparent precision, 
there's no promise that the actual value returned by the OS has that much 
precision.  You should be fine if all you're looking for is ms, but I 
wouldn't count on much more than that.


From http  Fri Jul 24 21:30:46 2009
From: http (Paul Rubin)
Date: 24 Jul 2009 18:30:46 -0700
Subject: pack an integer into a string
References: <4a6a357c$0$6161$4fafbaef@reader5.news.tin.it>
Message-ID: <7xvdlh8s6x.fsf@ruckus.brouhaha.com>

superpollo <user at example.net> writes:
>   >>> number = 252509952
>   >>> hex(number)
>   '0xf0cff00'
>   >>>
> 
> so i would like a string like '\xf0\xcf\xf0\x00'

def encode(number):
   h = '%x' % number
   if len(h) % 2 == 1:
     h = '0' + h 
   return h.decode('hex')


From pfeldman at verizon.net  Fri Jul 24 22:30:12 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 24 Jul 2009 19:30:12 -0700 (PDT)
Subject: list vs. tuple [Re: len() should always return something]
In-Reply-To: <Xns9C52E231DF188duncanbooth@127.0.0.1>
References: <24639361.post@talk.nabble.com>
	<1078183501.1917310.1248451116880.JavaMail.root@vms244.mailsrvcs.net>
	<roy-89AEB3.15032824072009@news.panix.com>
	<Xns9C52E231DF188duncanbooth@127.0.0.1>
Message-ID: <24654347.post@talk.nabble.com>


isinstance(x, (int, float, complex))

is certainly very compact, and does what I want.  Thanks!
-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24654347.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From pfeldman at verizon.net  Fri Jul 24 22:33:30 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 24 Jul 2009 19:33:30 -0700 (PDT)
Subject: len() should always return something
In-Reply-To: <0279f6df$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <24654358.post@talk.nabble.com>


"As far as I know, there is no programming language which treats scalars like
ints as if they were 
vectors of length 1"

Actually, Matlab does:

>> length(5)
ans =
     1
>> 
-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24654358.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From rurpy at yahoo.com  Fri Jul 24 22:41:50 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Fri, 24 Jul 2009 19:41:50 -0700 (PDT)
Subject: regex: multiple matching for one string
References: <3559c849-b650-4284-ae05-96db5da1d5f2@y10g2000prf.googlegroups.com>
	<mailman.3588.1248355389.8015.python-list@python.org>
	<zpSdnXJ_FNFaHPXXnZ2dnUVZ_u-dnZ2d@earthlink.com> 
	<e3f0beee-593b-40ae-8dfd-54145f4c9da8@o36g2000vbl.googlegroups.com> 
	<o7Kdncbpm-78SvTXnZ2dnUVZ_vmdnZ2d@pdx.net>
Message-ID: <d273d586-bd4e-4bcc-b6f3-dca969e3bcd7@i6g2000yqj.googlegroups.com>

Scott David Daniels wrote:
> rurpy at yahoo.com wrote:
>> Nick Dumas wrote:
>>> On 7/23/2009 9:23 AM, Mark Lawrence wrote:
>>>> scriptlearner at gmail.com wrote:
>>>>> For example, I have a string "#a=valuea;b=valueb;c=valuec;", and I
>>>>> will like to take out the values (valuea, valueb, and valuec).  How do
>>>>> I do that in Python?  The group method will only return the matched
>>>>> part.  Thanks.
>>>>>
>>>>> p = re.compile('#a=*;b=*;c=*;')
>>>>> m = p.match(line)
>>>>>         if m:
>>>>>              print m.group(),
>>>> IMHO a regex for this is overkill, a combination of string methods such
>>>> as split and find should suffice.
>>
>> You're saying that something like the following
>> is better than the simple regex used by the OP?
>> [untested]
>> values = []
>> parts = line.split(';')
>> if len(parts) != 4: raise SomeError()
>> for p, expected in zip (parts[-1], ('#a','b','c')):
>>     name, x, value = p.partition ('=')
>>     if name != expected or x != '=':
>>         raise SomeError()
>>     values.append (value)
>> print values[0], values[1], values[2]
>
> I call straw man: [tested]
>      line = "#a=valuea;b=valueb;c=valuec;"
>      d = dict(single.split('=', 1)
>               for single in line.split(';') if single)
>      d['#a'], d['b'], d['c']
> If you want checking code, add:
>      if len(d) != 3:
>          raise ValueError('Too many keys: %s in %r)' % (
>                               sorted(d), line))

OK, that seems like a good solution.  It certainly
wasn't an obvious solution to me.  I still have no
problem maintaining that

      [tested]
      line = "#a=valuea;b=valueb;c=valuec;"
      m = re.match ('#a=(.*);b=(.*);c=(.*);', line)
      m.groups((1,2,3))
(If you want checking code, nothing else required.)

is still simpler and clearer (with the obvious
caveat that one is familiar with regexes.)

>> Blech, not in my book.  The regex checks the
>> format of the string, extracts the values, and
>> does so very clearly.  Further, it is easily
>> adapted to other similar formats, or evolutionary
>> changes in format.  It is also (once one is
>> familiar with regexes -- a useful skill outside
>> of Python too) easier to get right (at least in
>> a simple case like this.)
> The posted regex doesn't work; this might be homework, so
> I'll not fix the two problems.  The fact that you did not
> see the failure weakens your claim of "does so very clearly."

Fact? Maybe you should have read the whole thread before
spewing claims that I did not see the regex problem.
The fact that you did not bother to weakens any claims
you make in this thread.
(Of course this line of argumentation is stupid anyway --
even had I not noticed the problem, it would say nothing
about the general case.  My advice to you is not to try
to extrapolate when the sample size is one.)


From pfeldman at verizon.net  Fri Jul 24 22:50:54 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 24 Jul 2009 19:50:54 -0700 (PDT)
Subject: len() should always return something
In-Reply-To: <7ct4b8F29mednU1@mid.uni-berlin.de>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
Message-ID: <24654439.post@talk.nabble.com>


Here's a simple-minded example:

def dumbfunc(xs):
   for x in xs:
      print x

This function works fine if xs is a list of floats, but not if it is single
float.  It can be made to work as follows:

def dumbfunc(xs):
   if isinstance(xs,(int,float,complex)): xs= [xs]
   for x in xs:
      print x

Having to put such extra logic into practically every function is one of the
annoying things about Python.

Phillip


Diez B. Roggisch-2 wrote:
> 
> Dr. Phillip M. Feldman schrieb:
>> Some aspects of the Python design are remarkably clever, while others
>> leave
>> me perplexed. Here's an example of the latter: Why does len() give an
>> error
>> when applied to an int or float? len() should always return something; in
>> particular, when applied to a scalar, it should return a value of 1. Of
>> course, I can define my own function like this:
>> 
>> def mylen(x):
>>    if isinstance(x,int) or isinstance(x,float): return 1
>>    return len(x)
>> 
>> But, this shouldn't be necessary.
> 
> Can you show some example of where that is actually making a piece of 
> code more elegant?
> 
> Diez
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 
> 

-- 
View this message in context: http://www.nabble.com/len%28%29-should-always-return-something-tp24639361p24654439.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From clp2 at rebertia.com  Fri Jul 24 23:02:40 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 24 Jul 2009 20:02:40 -0700
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<24654439.post@talk.nabble.com>
Message-ID: <50697b2c0907242002s1772783jed0a4a68177616cf@mail.gmail.com>

On Fri, Jul 24, 2009 at 7:50 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Here's a simple-minded example:
>
> def dumbfunc(xs):
> ? for x in xs:
> ? ? ?print x
>
> This function works fine if xs is a list of floats, but not if it is single
> float. ?It can be made to work as follows:
>
> def dumbfunc(xs):
> ? if isinstance(xs,(int,float,complex)): xs= [xs]
> ? for x in xs:
> ? ? ?print x
>
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

You can easily fix that using decorators:

(disclaimer: untested, except mentally)

#bit of setup; pays off later
def list_or_single(func):
    def wrapper(arg):
        try: iter(arg)
        except TypeError: arg = [arg]
        return func(arg)
    return wrapper

#now just prefix functions with @list_or_single

@list_or_single
def dumbfunc(xs):
    for x in xs:
        print x

Using the extended call syntax as I explained earlier is another option.

Cheers,
Chris
-- 
http://blog.rebertia.com


From davidj411 at gmail.com  Sat Jul 25 00:21:48 2009
From: davidj411 at gmail.com (davidj411)
Date: Fri, 24 Jul 2009 21:21:48 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<h4dhhf$1g5$1@ger.gmane.org>
	<mailman.3696.1248480299.8015.python-list@python.org>
Message-ID: <b2d13375-f653-417d-ae51-dee6f3e3ebad@j32g2000yqh.googlegroups.com>

could i see an example of this maybe?


From pavlovevidence at gmail.com  Sat Jul 25 00:55:26 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 24 Jul 2009 21:55:26 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
Message-ID: <aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>

On Jul 24, 11:06?am, Raffael Cavallaro
<raffaelcavall... at pas.espam.s.il.vous.plait.mac.com> wrote:
> On 2009-07-23 23:51:02 -0400, Carl Banks <pavlovevide... at gmail.com> said:
>
> > On Jul 23, 5:52?pm, Rui Maciel <rui.mac... at gmail.com> wrote:
> >> fft1976 wrote:
> >>> How do you explain that something as inferior as Python beat Lisp in
> >>> the market place despite starting 40 years later.
>
> >> Probably due to similar reasons that lead php to become remotely relevant
> > .
>
> > Well, the only reason PHP became relevant because it was an
> > easy
>
> ^^^^^^^^
> ^^^^^^^^ (emphasis added)
>
> > to
> > deploy solution in a single application domain, the web, that happened
> > to explode.
>
> i.e., Python "beat" lisp because it is ~70% of lisp in a form that is
> much more palatable to the average programmer, just as php became
> popular because it is powerful enough to do websites and, most
> importantly, apprehensible to mediocre programmers and even some
> non-programmers.

That the two languages made something easier is the beginning and end
of the similarities between them.

PHP made hacking together a security-hole-ridden website easier.
Python made actual programming easier.

PHP became what it is because it rode on the coattails of a technology
that grew in spite of it (kind of like everything Microsoft has
shipped since Windows 3.1).  Python became what it is because it
earned the respect of programmers, who contributed to it and spread
the word about it.  That it is easy to use is only a part of why it
earned that respect.  Two languages could not have come to prominence
by more different means.

I can handle Python being called inferior to Lisp or a language for
stupid people or a single-core-using dinosaur of a language or worse
than Perl.

But please don't put it on the same level as PHP.  Their situations
have almost nothing in common.


Carl Banks


From pavlovevidence at gmail.com  Sat Jul 25 01:44:04 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 24 Jul 2009 22:44:04 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org> 
	<4YGdnQ-7p7gzIPTXnZ2dnUVZ_oJi4p2d@posted.visi>
Message-ID: <e7c3b968-f492-46fb-a80a-e118aea9e3f9@v23g2000pro.googlegroups.com>

On Jul 24, 6:57?am, Grant Edwards <invalid at invalid> wrote:
> On 2009-07-24, Dr. Phillip M. Feldman <pfeld... at verizon.net> wrote:
>
>
>
> > Some aspects of the Python design are remarkably clever, while
> > others leave me perplexed. Here's an example of the latter:
> > Why does len() give an error when applied to an int or float?
> > len() should always return something; in particular, when
> > applied to a scalar, it should return a value of 1.
>
> If len(7) returned a value of 1, then wouldn't one expect 7[0]
> to be valid? ?It isn't, so you'd then have to redefine all
> types so that they are sequences that can be indexed. ?Sounds
> like a big mess to me...

You can call the big mess "Matlab".


Carl Banks


From andreengels at gmail.com  Sat Jul 25 01:47:14 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sat, 25 Jul 2009 07:47:14 +0200
Subject: time in milliseconds by calling time.time()
In-Reply-To: <roy-7CF120.21271024072009@news.panix.com>
References: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>
	<roy-7CF120.21271024072009@news.panix.com>
Message-ID: <6faf39c90907242247o4e6d50b6m5871faa7f08b447f@mail.gmail.com>

On Sat, Jul 25, 2009 at 3:27 AM, Roy Smith<roy at panix.com> wrote:

> Keep in mind that while a float may have a large apparent precision,
> there's no promise that the actual value returned by the OS has that much
> precision. ?You should be fine if all you're looking for is ms, but I
> wouldn't count on much more than that.

Even stronger: I wouldn't count on _anything_ more than that. On my
machine, time.time() changes value once per millisecond. I tested this
by looking at a loop that recorded time.time() 100000 times. The total
time in the loop was 61 ms; out of the 100000 numbers, 61 were higher
than the previous one, with the highest difference being 1.00017 ms,
the lowest 0.999928 ms.

-- 
Andr? Engels, andreengels at gmail.com


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 02:18:23 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 06:18:23 GMT
Subject: time in milliseconds by calling time.time()
References: <9c600f0c-f4a0-4e8c-bbb9-27f128aecc50@m7g2000prd.googlegroups.com>
	<roy-7CF120.21271024072009@news.panix.com>
	<mailman.3701.1248501160.8015.python-list@python.org>
Message-ID: <027a94a5$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 07:47:14 +0200, Andre Engels wrote:

> On Sat, Jul 25, 2009 at 3:27 AM, Roy Smith<roy at panix.com> wrote:
> 
>> Keep in mind that while a float may have a large apparent precision,
>> there's no promise that the actual value returned by the OS has that
>> much precision. ?You should be fine if all you're looking for is ms,
>> but I wouldn't count on much more than that.
> 
> Even stronger: I wouldn't count on _anything_ more than that. On my
> machine, time.time() changes value once per millisecond. I tested this
> by looking at a loop that recorded time.time() 100000 times. The total
> time in the loop was 61 ms; out of the 100000 numbers, 61 were higher
> than the previous one, with the highest difference being 1.00017 ms, the
> lowest 0.999928 ms.



I'm guessing you're running Windows, because for Windows time.time() has 
a low resolution and time.clock() is the higher resolution timer.

I'm running Linux, which is the opposite:


>>> from time import time, clock
>>> def diffs(alist):
...     deltas = []
...     for i in xrange(1, len(alist)):
...             deltas.append( alist[i] - alist[i-1] )
...     return deltas
...
>>> d = [time() for i in xrange(10000)]  # grab raw times
>>> dt = diffs(d)  # calculate the difference between each call
>>> max(dt), min(dt)
(0.00060892105102539062, 1.9073486328125e-06)
>>>
>>> d = [clock() for i in xrange(10000)]  # and again using clock()
>>> dc = diffs(d)
>>> max(dc), min(dc)
(0.010000000000000009, 0.0)

More important than the maximum and minimum time deltas is the resolution 
of ticks in each timer. Under Linux, clock() hardly ever gets updated:

>>> len(dc)  # how many time deltas?
9999
>>> len(filter(None, dc))  # how many non-zero deltas?
2

while time() gets updated frequently:

>>> len(dt)
9999
>>> len(filter(None, dt))
9999



See also the comments in the timeit module.



-- 
Steven


From gagsl-py2 at yahoo.com.ar  Sat Jul 25 02:44:14 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 25 Jul 2009 03:44:14 -0300
Subject: trouble with minidom
References: <9c8c445f0907211708qc187b53xe5085df6e894f8c9@mail.gmail.com>
	<op.uxf03pv8x6zn5v@lepton.softlabbsas.com.ar>
	<9c8c445f0907241056x11ec5316s2ea6310872cd342@mail.gmail.com>
Message-ID: <op.uxl2b0r0x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 24 Jul 2009 14:56:29 -0300, Ronn Ross <ronn.ross at gmail.com>  
escribi?:
> On Tue, Jul 21, 2009 at 7:32 PM, Gabriel Genellina
> <gagsl-py2 at yahoo.com.ar>wrote:
>> En Tue, 21 Jul 2009 21:08:57 -0300, Ronn Ross <ronn.ross at gmail.com>
>> escribi?:
>>
>>  Hello I'm trying to read an xml file using minidome. The xml looks  
>> like:
>>> <rootNode>
>>>   <project>
>>>      <name>myProj</name>
>>>      <path>/here/</path>
>>>   </project>
>>> </rootNode>
>
> I have used the loop below and it works great, but I need get both child
> elements or 'project' per iteration. I want to build a dictionary that
> resemble this:
> my_dict = {'myProj':'/here/', 'anothername':'anotherpath'}
>
> I couldn't find how to do with in the element tree docs. Can you point  
> me in
> the right direction?

py> import xml.etree.ElementTree as ET
py> xml = """<rootNode>
... <project>
...   <name>myProj</name>
...   <path>/here/</path>
... </project>
... <project>
...   <name>anothername</name>
...   <path>anotherpath</path>
... </project>
... </rootNode>"""
py> doc = ET.fromstring(xml)
py> result = {}
py> for project in doc.findall('project'):
...   name = project.find("name").text
...   path = project.find("path").text
...   result[name] = path
...
py> result
{'anothername': 'anotherpath', 'myProj': '/here/'}

The Element interface is documented here:
http://docs.python.org/library/xml.etree.elementtree.html#the-element-interface
More info in the author's site:
http://www.effbot.org/zone/element-index.htm

(Perhaps you're using Python 2.5? That part of the documentation was  
omited in the 2.5 doc set by mistake. Read the 2.6 docs instead, there was  
no changes)

-- 
Gabriel Genellina



From xahlee at gmail.com  Sat Jul 25 02:54:22 2009
From: xahlee at gmail.com (Xah Lee)
Date: Fri, 24 Jul 2009 23:54:22 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
Message-ID: <aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>

PHP is popular because it is geared for the server-side web scripting
lang, and simpler and easy to use, than popular free alternatives at
the time (such as Perl and Java's JSP).

Python became popular primarily because its ease-to-read syntax.

Btween the two, PHP is much easier to use, and much a pleasure to
program in. Python is a pain in the ass.

PHP is functional. The language is not elegant, lots of
inconsistancies. However, it's a joy to use for any practical task in
its web scripting field. PHP has one of the best documentation among
open source computer languages, i'd say top 5.

Python is a twist, with half-assed lambda, a culty community thinking
"computer science R us", and it has this OOP obsession. The Guido guy
do not understand functional programing, but has the pleasure to
actitively badmouth it.

References:

? Language, Purity, Cult, and Deception
  http://xahlee.org/UnixResource_dir/writ/lang_purity_cult_deception.html

? What Languages to Hate
  http://xahlee.org/UnixResource_dir/writ/language_to_hate.html

? Lambda in Python 3000
  http://xahlee.org/perl-python/python_3000.html

? Python Documentation Problems
  http://xahlee.org/perl-python/python_doc_index.html

? Examples Of Quality Documentation In The Computing Industry
  http://xahlee.org/perl-python/quality_docs.html

? Xah's Perl and Python Tutorial
  http://xahlee.org/perl-python/index.html

? Xah's PHP Tutorial
  http://xahlee.org/php/index.html

  Xah
? http://xahlee.org/

?


From andreengels at gmail.com  Sat Jul 25 02:55:40 2009
From: andreengels at gmail.com (Andre Engels)
Date: Sat, 25 Jul 2009 08:55:40 +0200
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<24654439.post@talk.nabble.com>
Message-ID: <6faf39c90907242355m1de6d4e2s6a575a6c7469b67f@mail.gmail.com>

On Sat, Jul 25, 2009 at 4:50 AM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> Here's a simple-minded example:
>
> def dumbfunc(xs):
> ? for x in xs:
> ? ? ?print x
>
> This function works fine if xs is a list of floats, but not if it is single
> float. ?It can be made to work as follows:
>
> def dumbfunc(xs):
> ? if isinstance(xs,(int,float,complex)): xs= [xs]
> ? for x in xs:
> ? ? ?print x
>
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

I don't have this problem - when I have a list of one element, that's
what I use - a list with one element. I think things would get much
simpler if you do such a conversion right at the Matlab-Python
interface, rather than changing all kind of things in Python so that
its types are more matlab-like. Just like you shouldn't program Python
by simply translating Java or C into Python idiom, you also shouldn't
program Python by trying to mimic Matlab. Each language has its own
strengths and weaknesses, and moving things over too much in a
simplistic fashion will usually mean that you get the weaknesses of
both and the strengths of neither.

-- 
Andr? Engels, andreengels at gmail.com


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 03:03:02 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 07:03:02 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
Message-ID: <027a9f1a$0$5185$c3e8da3@news.astraweb.com>

On Fri, 24 Jul 2009 19:50:54 -0700, Dr. Phillip M. Feldman wrote:

> Here's a simple-minded example:
> 
> def dumbfunc(xs):
>    for x in xs:
>       print x
> 
> This function works fine if xs is a list of floats, but not if it is
> single float.  It can be made to work as follows:
> 
> def dumbfunc(xs):
>    if isinstance(xs,(int,float,complex)):
>       xs= [xs]
>    for x in xs:
>       print x
> 
> Having to put such extra logic into practically every function is one of
> the annoying things about Python.


But it's not "practically every function". It's hardly any function at 
all -- in my code, I don't think I've ever wanted this behavior. I would 
consider it an error for function(42) and function([42]) to behave the 
same way. One is a scalar, and the other is a vector -- they're different 
things, it's poor programming practice to treat them identically.

(If Matlab does this, so much the worse for Matlab, in my opinion.)

However, if you want this behaviour, it's easy enough to get it with a 
decorator:

from functools import wraps
def matlab(func):
    """Decorate func so that it behaves like Matlab, that is, 
    it considers a single scalar argument to be the same as a 
    vector of length one."""
    @wraps(func)
    def inner(arg, **kwargs):
        # If arg is already a vector, don't touch it.
        try:
            # If this succeeds, it's a vector of some type.
            iter(arg)
        except TypeError:
            # It's a scalar.
            arg = [arg]
        # Now call the decorated function (the original).
        return func(arg, **kwargs)
    return inner

With this decorator in hand, you can now easily get the behaviour you 
want with a single extra line per function:

>>> @matlab
... def mean(numbers):
...     return sum(numbers)/len(numbers)
...
>>> mean([4.5])
4.5
>>> mean(4.5)
4.5
>>> mean([4.5, 3.6])
4.0499999999999998


Decorators are extremely powerful constructs, and well worth learning. As 
an example, here's a similar decorator that will accept multiple 
arguments, like the built-in functions min() and max():

def one_or_many(func):
    """Decorate func so that it behaves like the built-ins
    min() and max()."""
    @wraps(func)
    def inner(*args, **kwargs):
        # If we're given a single argument, and it's a vector, 
        # use it as args.
        if len(args) == 1:
            try:
                iter(args[0])
            except TypeError:
                pass
            else:
                # No exception was raised, so it's a vector.
                args = args[0]
        # Now call the decorated function (the original).
        return func(args, **kwargs)
    return inner


And then use it:

>>> @one_or_many
... def minmax(numbers):
...     """Return the minimum and maximum element of numbers, 
...     making a single pass."""
...     # the following will fail if given no arguments
...     smallest = biggest = numbers[0]  
...     for x in numbers[1:]:
...             if x < smallest:
...                     smallest = x
...             elif x > biggest:
...                     biggest = x
...     return (smallest, biggest)
...
>>>
>>> minmax([2, 4, 6, 8, 1, 3, 5, 7])
(1, 8)
>>> minmax(2, 4, 6, 8, 1, 3, 5, 7)
(1, 8)




-- 
Steven


From tayssir.john at googlemail.com  Sat Jul 25 03:23:45 2009
From: tayssir.john at googlemail.com (Tayssir John Gabbour)
Date: Sat, 25 Jul 2009 00:23:45 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<12ce2d31-5028-4b60-a5b1-5d5bf1fc06d7@f20g2000prn.googlegroups.com>
Message-ID: <b85f35ca-f983-4cc3-8763-ee34f825407b@p36g2000prn.googlegroups.com>

On Jul 24, 11:58 pm, ACL <anonymous.c.lis... at gmail.com> wrote:
> I actually think that the thing holding lisp back is 'bus factor'.
>
> Lets assume I have a java project and a lisp project:
>
> Java project:
> I have maybe 10 or 12 people on my team working on various subsystems
> of my project. There are probably one or two 'technical leader' types
> in the group, and a bunch of others who are sort of 'serfs', banging
> out java classes. Lets say one of my important guys gets totally
> splattered by a bus... I've still got another one left! I can rely on
> the other guy to keep things afloat while I train up a new leader
> type.
>
> Lisp project:
> I don't need as many people. I have 3 or 4 people, and one person is
> my technical leader and lisp guru. Guru is probably in charge of more
> difficult macros and (because of that), also in charge of the overall
> design (macros are design patterns embodied in code). Lets say he gets
> totally annihilated by the bus. What do I do now? I had all my eggs in
> one basket and my project is now stalled.

A Clojure programmer mentioned interesting solutions to this used by
his company, such as partnerships with similarly Agile companies.
http://programmingtour.blogspot.com/2009/07/conversation-with-stuart-halloway.html

I agree that the bus factor -- as well as some other problems -- works
against Lisp's acceptance.


All the best,
Tayssir


From pavlovevidence at gmail.com  Sat Jul 25 03:49:12 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 25 Jul 2009 00:49:12 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <e82da500-2015-4a75-b77b-32fc4e731567@a39g2000pre.googlegroups.com>

On Jul 23, 11:35?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> Some aspects of the Python design are remarkably clever, while others leave
> me perplexed. Here's an example of the latter: Why does len() give an error
> when applied to an int or float? len() should always return something; in
> particular, when applied to a scalar, it should return a value of 1. Of
> course, I can define my own function like this:
>
> def mylen(x):
> ? ?if isinstance(x,int) or isinstance(x,float): return 1
> ? ?return len(x)
>
> But, this shouldn't be necessary.

I knew that you were coming from Matlab as soon as I saw the subject
line.

I use both Matlab and Python very often, and I understand the design
decisions behind both (insofar as Matlab can be considered a
"design").

The thing to keep in mind about Python is that it's a general purpose
language, not just for mathematical computation, and there are some
things in Python that are a bit suboptimal for math calculations.
This is one of them: when the types of objects you are dealing with
most often are numbers, then there's not much chance for ambiguity
when treating a scalar as a 1x1 matrix.

However, when doing general purpose programming, you often use lots of
types besides numbers, some of which are containers themselves.  This
creates the possibility of ambiguity and inconsistent behavior.  Let's
consider your example function.

def dumbfunc(xs):
   for x in xs:
      print x

You can use it on an list, like this, and there is no ambiguity:

dumbfunc([1,2,3])

Now suppose Python allowed numbers to be treated as degenerate
sequences of length 1.  Then you could pass a number, and it would
work as you expect:

dumbfunc(1)

However, because Python is general purpose, you might also want to
pass other types around, such as strings.  Say you wanted to print a
list of string, you would do this, and it would work as expected:

dumbfunc(["abc","def","ghi"])

Now, the problem.  In the numbers example, you were able to treat a
single number as a degenerate list, and by our supposition, it
worked.  By analogy, you would expect to be able to do the same with a
list of strings, like this:

dumbfunc("abc")

Whoops: doesn't work.  Instead of printing one string "abc" it prints
three strings, "a", "b", and "c".

By allowing scalar numbers to act as degenerate lists, you've
introduced a very bad inconsistency into the language, you've made it
difficult to learn the language by analogy.

For a general purpose language there is really no second-guessing this
design decision.  It would be unequivocally bad to have atomic types
act like sequences.  The reason it isn't so bad in Matlab is that you
can rely on the elements of an array to be scalar.

Matlab, for its part, does contain some types (cell arrays and
structures) that can contain non-scalars for cases when you want to do
that.  However, you will notice that no scalar will ever be treated as
a degenerate cell array or structure.  Even a poorly designed, ad hoc
language like Matlab won't try to treat scalar numbers as cell arrays,
because ambiguity like I described above will appear.  Nope, it takes
an abomination like Perl to do that.

As for how I would recommend you translate the Matlab function that
rely on this: you need to decide whether that scalar number you are
passing in is REALLY a scalar, or a degenerate vector.  If it's the
latter, just get over it and pass in a single-item list.  I have done
these kinds of conversions myself before, and that's the way to do
it.  Trying to be cute and writing functions that can work with both
types will lead to trouble and inconsistency, especially if you are a
Python newbie.  Just pass in a list if your function expects a list.


Carl Banks


From hendrik at microcorp.co.za  Sat Jul 25 03:50:30 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 09:50:30 +0200
Subject: len() should always return something
In-Reply-To: <f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<mailman.3661.1248444714.8015.python-list@python.org>
	<f8ee55b4-1fde-4150-a9da-1b484fe5b566@a26g2000yqn.googlegroups.com>
Message-ID: <200907250950.30999.hendrik@microcorp.co.za>


On Friday 24 July 2009 16:45:40 Mark Dickinson wrote:

> On Jul 24, 3:11?pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
>
> wrote:
> > Which doesn't make your point less valid. ?In fact I'd go so
> > far as to argue that what len() gives you is the number of
> > items in a container, so len(7) should return 0.
>
> Nah.  7 contains three bits, so len(7) should *clearly* return 3.

Almost right - however the first seven that you typed was a string
seven and not an int - so the hex is 37 and that takes at least
six bits...

:-)

Now if only someone can figure out a reason why it should
return seven, then it would be perfect!

- Hendrik


From deets at nospam.web.de  Sat Jul 25 03:55:26 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sat, 25 Jul 2009 09:55:26 +0200
Subject: len() should always return something
In-Reply-To: <mailman.3699.1248490256.8015.python-list@python.org>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
Message-ID: <7cvs3fF24hjh7U1@mid.uni-berlin.de>

Dr. Phillip M. Feldman schrieb:
> Here's a simple-minded example:
> 
> def dumbfunc(xs):
>    for x in xs:
>       print x
> 
> This function works fine if xs is a list of floats, but not if it is single
> float.  It can be made to work as follows:
> 
> def dumbfunc(xs):
>    if isinstance(xs,(int,float,complex)): xs= [xs]
>    for x in xs:
>       print x
> 
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

And where comes "len(xs)" into play here? What you want is iteration 
over scalars.

I do think that if you frequently have to write code like that, you are 
writing errorneous code.

But might that as it is, a simple


def iterable(i):
     if isinstance(i, (int, float, complex)):
        return [i]
     return i


is all you need. So you can write


for x in iterable(xs):


wherever you expect values to be either scalar or iterable.

Diez


From piet at cs.uu.nl  Sat Jul 25 04:03:58 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 10:03:58 +0200
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <m2tz11fatt.fsf@cs.uu.nl>

>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (S) wrote:

>S> Chris, I'm curious why you think that these Zen are relevant to the OP's 
>S> complaint.

>S> Re explicit vs implicit, len(42) is just as explicit as len([42, 23]).

>S> Arguably (I wouldn't argue this, but some people might) ints aren't 
>S> "special enough" to break the rule that len(obj) should always return 
>S> something.

>S> (I don't actually agree, but some people might be able to produce a 
>S> coherent argument why len() should apply equally to all objects.)

>S> Re errors passing silently, the OP doesn't believe that len(42) should be 
>S> an error, so that's not relevant.

>S> And there's nothing ambiguous about len(42).

len(42) should be 7.5 million.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From hendrik at microcorp.co.za  Sat Jul 25 04:10:32 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 10:10:32 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<mailman.3570.1248335976.8015.python-list@python.org>
	<f678c13f-2f77-43f2-92c2-d20d36f66fe6@k1g2000yqf.googlegroups.com>
Message-ID: <200907251010.32720.hendrik@microcorp.co.za>

On Friday 24 July 2009 17:07:30 Inky 788 wrote:
> On Jul 23, 3:42?am, Hendrik van Rooyen <hend... at microcorp.co.za>
>
> wrote:
8<------------------------
> > Steven showed why you cannot have a mutable thing
> > as a key in a dict.
> >
> > if you think it is contrived, then please consider how you would
> > keep track of say the colour of a pixel on a screen at position
> > (x,y) - this is about the simplest "natural" tuple format and
> > example.
>
> My guess is that this is probably the way most people do it:
>
> ~~~~
> #!/usr/bin/env python
>
> import sys
> import random
>
> if len( sys.argv ) != 3:
>     print "Please pass exactly 2 ints. Exiting."
>     sys.exit(1)
>
> NUM_COLUMNS = int( sys.argv[1] )
> NUM_ROWS    = int( sys.argv[2] )
>
> print "Making array of %s columns by %s rows." % (NUM_COLUMNS,
> NUM_ROWS)
>
> def rand():
>     return int( 255 * random.random())
>
> def make_a_pixel():
>     #       red     green   blue
>     return [rand(), rand(), rand()]
>
> def make_a_row(num_columns):
>     temp_row = []
>     for i in range(num_columns):
>         temp_row.append( make_a_pixel() )
>     return temp_row
>
> def make_array_of_pixels(num_columns, num_rows):
>     rows = []
>     for i in range(num_rows):
>         rows.append( make_a_row(num_columns) )
>     return rows
>
> def show_pixels(pixel_array):
>     for row in pixel_array:
>         for pixel in row:
>             print pixel, '  ',
>         print
>
>
> rows_of_pixels = make_array_of_pixels(NUM_COLUMNS, NUM_ROWS)
>
> show_pixels(rows_of_pixels)
> ~~~~

Good grief! - Not a dictionary in sight!

I had something in mind where point was an (x,y) tuple,
and point_colours was a dict of possibly named points 
with a list of RGB values. 
(The colour can change, the point is fixed)

If I were doing it your way, I would use the Array module's Array.
But then, strictly speaking it would not be your way any more,
would it?

- Hendrik



From gagsl-py2 at yahoo.com.ar  Sat Jul 25 04:31:20 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 25 Jul 2009 05:31:20 -0300
Subject: How do I generate dia diagrams from python source code?
References: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
Message-ID: <op.uxl7aiixx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 24 Jul 2009 17:52:47 -0300, Qauzzix <qauzzix at gmail.com> escribi?:

> Since I have been using dia to make my UML diagrams. I also found an
> util named dia2code that generates python code from dia diagram. Now
> that I have that option I really want to find a way to generate dia
> diagram from existing code and/or maintain my diagrams.
>
> I have been googling  like crazy trying to find a way but with no
> luck. Anyone here know how to do this?

SPE does that: http://pythonide.stani.be/

-- 
Gabriel Genellina



From hendrik at microcorp.co.za  Sat Jul 25 05:01:46 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 11:01:46 +0200
Subject: len() should always return something
In-Reply-To: <roy-B8E460.15045524072009@news.panix.com>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<0279f596$0$5185$c3e8da3@news.astraweb.com>
	<roy-B8E460.15045524072009@news.panix.com>
Message-ID: <200907251101.46672.hendrik@microcorp.co.za>

On Friday 24 July 2009 21:04:55 Roy Smith wrote:


> Compressing strings to a single bit is easy.  It's the uncompressing that's
> tricky.

Not really - all you have to do is to apply the EXACT same sequence
of operations that compressed it, in reverse.

The unfortunate part is that this information is in almost all cases
larger than the original, uncompressed string, so that it kind of defeats
the object of compression.

So yes - tricky!

:-)

- Hendrik




From dr.mtarver at ukonline.co.uk  Sat Jul 25 05:30:16 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Sat, 25 Jul 2009 02:30:16 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3636.1248390216.8015.python-list@python.org>
	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>
Message-ID: <948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>

On 24 July, 15:45, nn <prueba... at latinmail.com> wrote:
> On Jul 23, 7:03?pm, Dave Angel <da... at ieee.org> wrote:
>
>
>
>
>
> > Mark Tarver wrote:
> > > I have a very strange error. ?I have two test python files test.py and
> > > python.py which contain the following code
>
> > > #!/usr/bin/python
> > > print "Content-type: text/html"
> > > print
> > > print "<html>"
> > > print "<center>Hello, Linux.com!</center>"
> > > print "</html>"
>
> > > One file (test.py) works; you call it up and it shows a web page with
>
> > > Hello, Linux.com
>
> > > The other fails with a server configuration error. ?Both are running
> > > under Linux, same server, same permissions. ?Running a character scan
> > > shows that both files contain the same printable characters and are
> > > therefore typographically identical. ? They are absolutely the same.
>
> > > The only hint at a difference I can see is that my ftp program says
> > > the files are of unequal lengths. ?test.py is 129 bytes long.
> > > python.py 134 bytes long.
>
> > > A zipped folder containing both files is at
>
> > >www.lambdassociates.org/weird.zip
>
> > > Any ideas welcome.
>
> > > Mark
>
> > Easiest explanation is that python.py has Windows-style newlines. ?In
> > other words, each line ends with 0d0a, rather than the Unix convention
> > of 0a.
>
> > If your server is Unix-based, it can't handle that first line, since it
> > has an illegal character (0d) following the
>
> > #!/usr/bin/python
>
> > line. ?Convert it to Unix line-endings.
>
> > DaveA
>
> Use dos2unix for conversion of the longer file and try again:
>
> http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm- Hide quoted text -
>
> - Show quoted text -

That sounds the ticket - but is there anything that runs under Windows
to do the trick?

Mark


From hendrik at microcorp.co.za  Sat Jul 25 05:34:13 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 11:34:13 +0200
Subject: len() should always return something
In-Reply-To: <h4d4dc$jav$1@adenine.netfront.net>
References: <mailman.3644.1248417347.8015.python-list@python.org>
	<roy-B8E460.15045524072009@news.panix.com>
	<h4d4dc$jav$1@adenine.netfront.net>
Message-ID: <200907251134.13221.hendrik@microcorp.co.za>

On Friday 24 July 2009 22:09:15 Marcus Wanner wrote:

> First one to correctly decompress the value 0 into an ASCII character
> wins the title of the world's most capable hacker :p

that is easy.

the xor of 0 and 1 is 1, which is ASCII soh, if I remember right.

soh is start of header.

Burroughs poll select, anyone?

- Hendrik



From dr.mtarver at ukonline.co.uk  Sat Jul 25 05:46:14 2009
From: dr.mtarver at ukonline.co.uk (Mark Tarver)
Date: Sat, 25 Jul 2009 02:46:14 -0700 (PDT)
Subject: strange python scripting error
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>
	<mailman.3636.1248390216.8015.python-list@python.org>
	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>
	<948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>
Message-ID: <0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>

On 25 July, 10:30, Mark Tarver <dr.mtar... at ukonline.co.uk> wrote:
> On 24 July, 15:45, nn <prueba... at latinmail.com> wrote:
>
>
>
>
>
> > On Jul 23, 7:03?pm, Dave Angel <da... at ieee.org> wrote:
>
> > > Mark Tarver wrote:
> > > > I have a very strange error. ?I have two test python files test.py and
> > > > python.py which contain the following code
>
> > > > #!/usr/bin/python
> > > > print "Content-type: text/html"
> > > > print
> > > > print "<html>"
> > > > print "<center>Hello, Linux.com!</center>"
> > > > print "</html>"
>
> > > > One file (test.py) works; you call it up and it shows a web page with
>
> > > > Hello, Linux.com
>
> > > > The other fails with a server configuration error. ?Both are running
> > > > under Linux, same server, same permissions. ?Running a character scan
> > > > shows that both files contain the same printable characters and are
> > > > therefore typographically identical. ? They are absolutely the same.
>
> > > > The only hint at a difference I can see is that my ftp program says
> > > > the files are of unequal lengths. ?test.py is 129 bytes long.
> > > > python.py 134 bytes long.
>
> > > > A zipped folder containing both files is at
>
> > > >www.lambdassociates.org/weird.zip
>
> > > > Any ideas welcome.
>
> > > > Mark
>
> > > Easiest explanation is that python.py has Windows-style newlines. ?In
> > > other words, each line ends with 0d0a, rather than the Unix convention
> > > of 0a.
>
> > > If your server is Unix-based, it can't handle that first line, since it
> > > has an illegal character (0d) following the
>
> > > #!/usr/bin/python
>
> > > line. ?Convert it to Unix line-endings.
>
> > > DaveA
>
> > Use dos2unix for conversion of the longer file and try again:
>
> >http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm-Hide quoted text -
>
> > - Show quoted text -
>
> That sounds the ticket - but is there anything that runs under Windows
> to do the trick?
>
> Mark- Hide quoted text -
>
> - Show quoted text -

OK, got a version

http://www.bastet.com/

has dos2unix.exe for Windows.  And it solves the problem.

Many thanks all for help on this baffling error

Mark


From piet at cs.uu.nl  Sat Jul 25 06:20:37 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 12:20:37 +0200
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<mailman.3662.1248445305.8015.python-list@python.org>
	<m23a8mi0m9.fsf@cs.uu.nl>
	<mailman.3673.1248458763.8015.python-list@python.org>
Message-ID: <m2zlatdpxm.fsf@cs.uu.nl>

>>>>> "Rhodri James" <rhodri at wildebst.demon.co.uk> (RJ) wrote:

>RJ> The point was, and remains, that this newsgroup gets regular traffic
>RJ> from people who expect Python's variables to act like C's variables,
>RJ> demonstrating that describing them as "quite compatible" is somewhat
>RJ> misleading.

So let' study these postings carefully to see what the actual confusion
is. I myself think that the confusion is not so much the variable
concept but the vale vs. reference semantics of objects. As such the
same thing plays a role in Java. Although the binding mechanisms in Java
and Python are different I don't think the actual semantics are so much
difference as to cause much confusion (with C it could be more). But
such a study could reveal that.

BTW. Which postings from (say) the last month did you have in mind?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jon at ffconsultancy.com  Sat Jul 25 07:02:08 2009
From: jon at ffconsultancy.com (Jon Harrop)
Date: Sat, 25 Jul 2009 12:02:08 +0100
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<12ce2d31-5028-4b60-a5b1-5d5bf1fc06d7@f20g2000prn.googlegroups.com>
Message-ID: <q8GdnQhErZpFSPfXnZ2dnUVZ8gVi4p2d@brightview.co.uk>

ACL wrote:
> Lisp project:
> I don't need as many people...

Is there any actual evidence of that?

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
http://www.ffconsultancy.com/?u


From piet at cs.uu.nl  Sat Jul 25 07:14:08 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 13:14:08 +0200
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<h4dhhf$1g5$1@ger.gmane.org>
	<mailman.3696.1248480299.8015.python-list@python.org>
	<b2d13375-f653-417d-ae51-dee6f3e3ebad@j32g2000yqh.googlegroups.com>
Message-ID: <m2vdlhdngf.fsf@cs.uu.nl>

>>>>> davidj411 <davidj411 at gmail.com> (d) wrote:

>d> could i see an example of this maybe?

queue is a shared Queue instance.

The parent puts the work in the queue with queue.put(work_object).
After all work has been put in the queue it puts a sentinel

	queue.put(None)

Each child thread (consumer) has a loop getting things out of the queue:

while True:
	work = queue.get()
	if work is None: break
	#do real stuff using work

queue.put(None) #put back the sentinel for other worker threads.

#finish

(Thanks to Dennis Lee Bieber)

Instead of None you can also create a special sentinel object and use that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From davea at ieee.org  Sat Jul 25 07:18:58 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 25 Jul 2009 07:18:58 -0400
Subject: strange python scripting error
In-Reply-To: <0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>	<mailman.3636.1248390216.8015.python-list@python.org>	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>	<948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>
	<0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>
Message-ID: <4A6AEA22.1030207@ieee.org>

Mark Tarver wrote:
> <snip>
>   
>>
>>> Use dos2unix for conversion of the longer file and try again:
>>>       
>>> http://linux.about.com/od/commands/l/blcmdl1_dos2uni.htm-Hide quoted text -
>>>       
>>> - Show quoted text -
>>>       
>> That sounds the ticket - but is there anything that runs under Windows
>> to do the trick?
>>
>> Mark- Hide quoted text -
>>
>> - Show quoted text -
>>     
>
> OK, got a version
>
> http://www.bastet.com/
>
> has dos2unix.exe for Windows.  And it solves the problem.
>
> Many thanks all for help on this baffling error
>
> Mark
>
>   
I use metapad for simple text editing, see    
http://en.wikipedia.org/wiki/Metapad

It's free, loads very quickly, and has a number of features I like.  One 
of its trivial features is to read/write files in four different 
formats.  In the file menu, you just choose what file-format you need now.

Another thing I'd point out is that some ftp programs will do this 
conversion as the file is being sent between a local DOS machine and a 
Unix machine on the internet.


DaveA



From gert.cuykens at gmail.com  Sat Jul 25 07:45:31 2009
From: gert.cuykens at gmail.com (gert)
Date: Sat, 25 Jul 2009 04:45:31 -0700 (PDT)
Subject: cgi.fieldstorage()
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
	<f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
	<7cv268F29q0j5U1@mid.uni-berlin.de>
Message-ID: <13ed9818-aacd-4260-800b-a04177e13681@n11g2000yqb.googlegroups.com>

On Jul 25, 2:33?am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> gert schrieb:
>
> > On Jul 24, 7:32 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> >> gert schrieb:
>
> >>> this is a non standard way to store multi part post data on disk
> >>> def application(environ, response):
> >>> ? ? with open('/usr/httpd/var/wsgiTemp','w') as f:
> >>> ? ? ? ? while True:
> >>> ? ? ? ? ? ? chunk = environ['wsgi.input'].read(8192).decode('latin1')
> >>> ? ? ? ? ? ? if not chunk: break
> >>> ? ? ? ? ? ? f.write(chunk)
> >>> ? ? response('200 OK',[])
> >>> ? ? return ['complete']
> >>> my question is how do i handle the file, so i can shuffle it into a db
> >>> using small chunks of memorie ?
> >> I don't think that's possible with the current DB-API. There is no
> >> stream-based BLOB-interface (as e.g. JDBC offers).
>
> >> So the answer certainly depends on your used RDBMS. For oracle, you
> >> would be lucky:
>
> >>http://cx-oracle.sourceforge.net/html/lob.html
>
> >> Other adapters I don't know about.
>
> > sqlite :) ok let say for now it would be impossible on a db level, but
> > before i reach the impossible, i still need to parse the file to
> > prepare the chunks. How do i do that ? How do i get the chunks without
> > loading the hole file into memorie ?
>
> It's memory - memorie might be some nice dutch girl you know :)
>
> Apart from that, your code above does exactly that - reads the data
> chunkwise. If the WSGI-implementation works proper, this will be the
> socket's input stream, so there is no memory overhead involved.
>
> Now of course if you want to have a multi-pass processing of the file
> without putting it into memory, then you need to save it to the harddisk
> befor.
>
> But honestly - we are talking about a web-application here. My
> DSL-connection has 1 MBit upstream, the average server has at least 2GB
> of memory available - so we are talking 20000 seconds uploading time to
> fill that memory. Which is about 5 hours. And you are decoding the data
> to a certain decoding, so we are not talking about binary data here -
> are you really sure memory is an issue?
>

What about some http upload resume features ?


From pavlovevidence at gmail.com  Sat Jul 25 07:45:48 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 25 Jul 2009 04:45:48 -0700 (PDT)
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net> 
	<8763di5d1d.fsf@benfinney.id.au>
Message-ID: <2977b59f-6843-4c2e-86c2-c0fa5dfdcf72@u38g2000pro.googlegroups.com>

On Jul 24, 8:14?am, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Hrvoje Niksic <hnik... at xemacs.org> writes:
> > The term "variable" is used in the Python language reference and
> > elsewhere
>
> Yes. It should also be abundantly clear from the constant stream of
> confused newbies on this point that its usage of that term is different
> to what many expect from usage elsewhere.

Personally, I haven't noticed a constant stream, just a few here and
there.

I expect that someone used to C variables will expect Python variables
to behave the same way even if you call them something different, so
what really is the point?


Carl Banks


From pavlovevidence at gmail.com  Sat Jul 25 07:49:09 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Sat, 25 Jul 2009 04:49:09 -0700 (PDT)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net> 
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net> 
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com> 
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>
Message-ID: <7fa7aa37-fd9e-4702-85f8-1f9b9a05c54d@i18g2000pro.googlegroups.com>

On Jul 24, 11:54?pm, Xah Lee <xah... at gmail.com> wrote:
[snip]
> References:
>
> ? Language, Purity, Cult, and Deception
> ?http://xahlee.org/UnixResource_dir/writ/lang_purity_cult_deception.html
>
> ? What Languages to Hate
> ?http://xahlee.org/UnixResource_dir/writ/language_to_hate.html
>
> ? Lambda in Python 3000
> ?http://xahlee.org/perl-python/python_3000.html
>
> ? Python Documentation Problems
> ?http://xahlee.org/perl-python/python_doc_index.html
>
> ? Examples Of Quality Documentation In The Computing Industry
> ?http://xahlee.org/perl-python/quality_docs.html
>
> ? Xah's Perl and Python Tutorial
> ?http://xahlee.org/perl-python/index.html
>
> ? Xah's PHP Tutorial
> ?http://xahlee.org/php/index.html
>
> ? Xah
> ?http://xahlee.org/

Wow, you leave no stone unturned.


> "computer science R us"

I'm stealing this.


Carl BAnks


From marcusw at cox.net  Sat Jul 25 08:55:47 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 25 Jul 2009 08:55:47 -0400
Subject: len() should always return something
In-Reply-To: <mailman.3708.1248514333.8015.python-list@python.org>
References: <mailman.3644.1248417347.8015.python-list@python.org>	<roy-B8E460.15045524072009@news.panix.com>	<h4d4dc$jav$1@adenine.netfront.net>
	<mailman.3708.1248514333.8015.python-list@python.org>
Message-ID: <h4evck$r63$1@adenine.netfront.net>

On 7/25/2009 5:34 AM, Hendrik van Rooyen wrote:
> On Friday 24 July 2009 22:09:15 Marcus Wanner wrote:
> 
>> First one to correctly decompress the value 0 into an ASCII character
>> wins the title of the world's most capable hacker :p
> 
> that is easy.
> 
> the xor of 0 and 1 is 1, which is ASCII soh, if I remember right.
> 
> soh is start of header.
> 
> Burroughs poll select, anyone?
> 
> - Hendrik
> 
nope, not soh.

Marcus


From piet at cs.uu.nl  Sat Jul 25 08:57:19 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 14:57:19 +0200
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
References: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>
Message-ID: <m2iqhgex8w.fsf@cs.uu.nl>

>>>>> ryles <rylesny at gmail.com> (r) wrote:

>r> According to http://www.python.org/doc/essays/packages.html:
>r> "The import statement first tests whether the item is defined in the
>r> package; if not, it assumes it is a module and attempts to load it."

>r> However, I've noticed that once a module is imported using the
>r> `from pkg import mod' syntax, if its name is deleted from the
>r> package namespace then subsequent imports with `from' will fail.

This is incorrectly stated. Also on the initial import it will fail, not
just on subsequent imports.

piet$ python
Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39) 
[GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg import _impl
_impl # this is from a print statement in _impl to show that it did import
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: cannot import name _impl
>>> 

According to the documentation
<http://docs.python.org/library/functions.html#__import__> the statement
from pkg import _impl

_temp = __import__('pkg', globals(), locals(), ['_impl'], -1)
_impl = _temp._impl

This fails because _temp (the imported module) doesn't have a binding
for _impl because you deleted it. By the way, if you have a `normal'
package that doesn't do anything with the name _impl, after the import
the pkg module namespace will have got a binding for _impl although it is not
in your code. It will have been put there by the import code.
In the following example pkg2/__init__.py just contains the line 
A = 2

piet$ python
Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39) 
[GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg2 import _impl
_impl
>>> import sys
>>> dir(sys.modules['pkg2'])
['A', '__builtins__', '__doc__', '__file__', '__name__', '__package__', '__path__', '_impl']
>>> 

It is not clear to me, however what the order is of the statements in
__init__.py and the insertion of _impl in the module namespace.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 08:59:43 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 12:59:43 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com> <m2tz11fatt.fsf@cs.uu.nl>
Message-ID: <027af2b3$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 10:03:58 +0200, Piet van Oostrum wrote:

>>S> And there's nothing ambiguous about len(42).
> 
> len(42) should be 7.5 million.

And "I don't understand your reasoning".upper() should be "Millennium 
Hand and Shrimp!".

Every function would be ambiguous if we treat it as returning an 
arbitrary result. But we don't -- semantics do matter. We expect that 
string.upper() should return the string converted to uppercase, and 
that's not ambiguous because we already know what uppercase means. Even 
if somebody didn't know what uppercase meant, they would expect that it 
had a meaning, and it was just a matter of learning what it meant: for 
example, one might take string.upper() as any of:

* convert every letter a..z to A..Z

* convert the first letter of each word to A..Z

* throw away the argument and return the literal "upper"

* count how many characters are in A..Z

and so forth.

These are some of the infinite number of *possible* meanings to 
string.upper(), but only one of them is the *actual* meaning. The method 
isn't ambiguous, because the language designers have chosen one meaning, 
and having learned what that meaning is, it's the *only* meaning you can 
legitimately use. If you (generic you) are uncertain what that meaning 
is, that's uncertainty, not ambiguity.

Similarly, we might be uncertain about the meaning of len(42) -- 
reasonable values it might return are 0, 1, 2, the number of bits in 42, 
and possibly even 7.5 million as you suggest. But that's our ignorance, 
due to the fact that we haven't yet agreed on a meaning to len(42), and 
not ambiguity: having made up our mind what len(42) should mean, it could 
only mean one thing.

However, mixed string/integer addition is a good example of ambiguity. We 
can add strings:

"1" + "2" => "12"

and we can add integers:

1 + 2 => 3

but it is ambiguous as to what "1" + 2 should return. Guido might have 
made Python behave like Perl, and define addition of a string and an int, 
but there would still be ambiguity in the expression, because we can't 
tell if the coder intended "1"+"2" and forgot to quote the two, or 
intended 1+2 and forgot to convert the string "1" to an int.

Ambiguity essentially boils down to being unable to reasonably predict 
the expectation of the coder. I say "reasonably", because if you allow 
unreasonable situations, everything is "ambiguous":

I typed:

    x = 42 + y

but maybe I intended to import the math module, therefore the + operator 
is ambiguous. Reasonable? No, because we're allowed to assume the coder 
is rational, and mistakes are small.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sat Jul 25 09:37:51 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 25 Jul 2009 13:37:51 GMT
Subject: non-owning references?
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87d47q5ixx.fsf@benfinney.id.au> <87fxcm5gny.fsf@busola.homelinux.net>
	<8763di5d1d.fsf@benfinney.id.au>
	<2977b59f-6843-4c2e-86c2-c0fa5dfdcf72@u38g2000pro.googlegroups.com>
Message-ID: <027afba2$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 04:45:48 -0700, Carl Banks wrote:

> On Jul 24, 8:14?am, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
>> Hrvoje Niksic <hnik... at xemacs.org> writes:
>> > The term "variable" is used in the Python language reference and
>> > elsewhere
>>
>> Yes. It should also be abundantly clear from the constant stream of
>> confused newbies on this point that its usage of that term is different
>> to what many expect from usage elsewhere.
> 
> Personally, I haven't noticed a constant stream, just a few here and
> there.
> 
> I expect that someone used to C variables will expect Python variables
> to behave the same way even if you call them something different, so
> what really is the point?

>From time to time we get newbies to Python assuming that len(list) is 
O(N), because the lists they learned about in Comp Sci 101 (or Lisp) are 
linked lists and traversing a linked list to count the items is O(N). Do 
you believe that if Python lists were called "arrays", or "waskilators", 
they would make the same mistake?

[Generalisation] 
C programmers have a mental model for how "variables" behave. They have 
no such mental model for how "objects bound to names" behave, and so they 
are less likely to jump to conclusions about the behaviour of name-
bindings. So I think you are mostly wrong.

However, only mostly -- human beings are generalisers par excellence, or 
rather, *over*-generalisers par excellence. Experienced coders are likely 
to rapidly realise that name-binding is very similar to the C variable 
model, and some percentage of them will over-generalise to assume that 
name-binding is the same as the C model. But if they do, at least that 
will be their fault for jumping to conclusions, not our fault for 
misleading them.


-- 
Steven


From piet at cs.uu.nl  Sat Jul 25 10:08:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 16:08:27 +0200
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<m2tz11fatt.fsf@cs.uu.nl>
	<027af2b3$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <m2eis4etyb.fsf@cs.uu.nl>

>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:

>SD> Ambiguity essentially boils down to being unable to reasonably predict 
>SD> the expectation of the coder. I say "reasonably", because if you allow 
>SD> unreasonable situations, everything is "ambiguous":

That's for me the reason that len(42) is ambiguous. The OP apparently
had 1 as expectation, whereas my first thought was the minimal number of
bits to represent the number and 7.5 million came later :=). The number
of bits I certainly find reasonable, and I would find the number of
decimal digits equally reasonable. More so than 1, actually. 1 as the
length of an int doesn't give any information.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From aahz at pythoncraft.com  Sat Jul 25 10:33:52 2009
From: aahz at pythoncraft.com (Aahz)
Date: 25 Jul 2009 07:33:52 -0700
Subject: comments? storing a function in an object
References: <mailman.3430.1248106983.8015.python-list@python.org>
	<f3d88edf-b5d3-43e4-89a3-b05ef0f55b47@p28g2000vbn.googlegroups.com>
	<h48lvm$qau$1@panix3.panix.com>
	<20efdb6a-c1a5-47dc-8546-7c4ae548e22d@g1g2000pra.googlegroups.com>
Message-ID: <h4f54g$2j9$1@panix3.panix.com>

In article <20efdb6a-c1a5-47dc-8546-7c4ae548e22d at g1g2000pra.googlegroups.com>,
Carl Banks  <pavlovevidence at gmail.com> wrote:
>On Jul 22, 8:38=A0pm, a... at pythoncraft.com (Aahz) wrote:
>> In article <f3d88edf-b5d3-43e4-89a3-b05ef0f55... at p28g2000vbn.googlegroups=
>.com>,
>> Carl Banks =A0<pavlovevide... at gmail.com> wrote:
>>>
>>>You have to be REALLY REALLY careful not to pass any user-supplied
>>>data to it if this is a server running on your computer, of course.
>>
>> Unless, of course, your users are paying for this service.
>
>Well, yes, but I assume that by the time you're deliberately letting
>users pay to run their programs on your server, you will already have
>deployed a full-blown, multi-tiered security strategy that includes
>validation by the server process.  That was sort of beyond the scope
>of the OP's question.

That's not necessarily a good assumption.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From aahz at pythoncraft.com  Sat Jul 25 11:20:51 2009
From: aahz at pythoncraft.com (Aahz)
Date: 25 Jul 2009 08:20:51 -0700
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
Message-ID: <h4f7sj$s6$1@panix3.panix.com>

In article <37da38d2-09a8-4fd2-94b4-5feae9675dcd at k1g2000yqf.googlegroups.com>,
Filip  <pinkeen at gmail.com> wrote:
>
>I tried to fix that with BeautifulSoup + regexp filtering of some
>particular cases I encountered. That was slow and after running my
>data scraper for some time a lot of new problems (exceptions from
>xpath parser) were showing up. Not to mention that BeautifulSoup
>stripped almost all of the content from some heavily broken pages
>(50+KiB page stripped down to some few hundred bytes). Character
>encoding conversion was a hell too - even UTF-8 pages had some non-
>standard characters causing issues.

Have you tried lxml?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From aahz at pythoncraft.com  Sat Jul 25 12:12:49 2009
From: aahz at pythoncraft.com (Aahz)
Date: 25 Jul 2009 09:12:49 -0700
Subject: strange error when trying to log something
References: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>
	<h49ah5$hv3$02$1@news.t-online.com>
Message-ID: <h4fau1$gvn$1@panix3.panix.com>

In article <h49ah5$hv3$02$1 at news.t-online.com>,
Peter Otten  <__peter__ at web.de> wrote:
>
>I have a hunch that you are triggering a reload() somewhere. Example:
>
>Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
>[GCC 4.3.3] on linux2
>Type "help", "copyright", "credits" or "license" for more information.
>>>> import weakref
>>>> weakref.WeakValueDictionary()
><WeakValueDictionary at 140598938447312>
>>>> import UserDict
>>>> reload(UserDict)
><module 'UserDict' from '/usr/lib/python2.6/UserDict.pyc'>
>>>> weakref.WeakValueDictionary()
>Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "/usr/lib/python2.6/weakref.py", line 51, in __init__
>    UserDict.UserDict.__init__(self, *args, **kw)
>TypeError: unbound method __init__() must be called with UserDict instance 
>as first argument (got WeakValueDictionary instance instead)

Nice sleuthing!  How did you figure that out?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From hendrik at microcorp.co.za  Sat Jul 25 12:15:37 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sat, 25 Jul 2009 18:15:37 +0200
Subject: len() should always return something
In-Reply-To: <027af2b3$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com> <m2tz11fatt.fsf@cs.uu.nl>
	<027af2b3$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <200907251815.37762.hendrik@microcorp.co.za>

On Saturday 25 July 2009 14:59:43 Steven D'Aprano wrote:
> On Sat, 25 Jul 2009 10:03:58 +0200, Piet van Oostrum wrote:
> >>S> And there's nothing ambiguous about len(42).
> >
> > len(42) should be 7.5 million.
>
> And "I don't understand your reasoning".upper() should be "Millennium
> Hand and Shrimp!".

That does it.
I will be kinder to you in future.
Anybody who quotes foul old Ron cannot be all bad.

- Hendrik



From albert at spenarnc.xs4all.nl  Sat Jul 25 13:27:52 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 25 Jul 2009 17:27:52 GMT
Subject: missing 'xor' Boolean operator
References: <mailman.3105.1247595911.8015.python-list@python.org>
	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>
	<h3j358$lhr$1@ger.gmane.org>
	<mailman.3164.1247670958.8015.python-list@python.org>
Message-ID: <knclug.j10@spenarnc.xs4all.nl>

In article <mailman.3164.1247670958.8015.python-list at python.org>,
Jean-Michel Pichavant  <jeanmichel at sequans.com> wrote:
>Christian Heimes wrote:
>> Chris Rebert wrote:
>>
>>> Using the xor bitwise operator is also an option:
>>> bool(x) ^ bool(y)
>>>
>>
>> I prefer something like:
>>
>>     bool(a) + bool(b) == 1
>>
>> It works even for multiple tests (super xor):
>>
>>   if bool(a) + bool(b) + bool(c) + bool(d) != 1:
>>       raise ValueError("Exactly one of a, b, c and d must be true")
>>
>> Christian
>>
>>
>While everyone's trying to tell the OP how to workaround the missing xor
>operator, nobody answered the question "why is there no xor operator ?".
>
>If the question was "Why is there no 'or' operator ?", would "because A
>or B <=> not(not A and not B)" be a proper answer ?

No. I think it is because and/or can be extended to be sensible
in a context where objects can be used. (What others have expressed
as having short-circuit evaluation. So sce indeed is the underlying
reason that and/or can be extended sensibly to objects.)

Remains whether we need an xor that only works and requires that
both operands are booleans. That one we have already!
It is called != .

(a!=b)!=c
and
a!=(b!=c)

are the same for booleans, so can indeed be expressed
a!=b!=c   (associativy of xor)

>
>JM
>
Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From tjreedy at udel.edu  Sat Jul 25 13:30:54 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sat, 25 Jul 2009 13:30:54 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <knclug.j10@spenarnc.xs4all.nl>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>
	<knclug.j10@spenarnc.xs4all.nl>
Message-ID: <h4ffge$44n$1@ger.gmane.org>

Albert van der Horst wrote:

> Remains whether we need an xor that only works and requires that
> both operands are booleans. That one we have already!
> It is called != .
> 
> (a!=b)!=c
> and
> a!=(b!=c)
> 
> are the same for booleans, so can indeed be expressed
> a!=b!=c   (associativy of xor)

Not in Python

 >>> a,b,c = True, False, True
 >>> (a!=b)!=c
False
 >>> a!=(b!=c)
False
 >>> a!=b!=c
True
 >>> (a!=b) and (b!=c)
True

In Math and Python, a<b<c means a<b and b<c, not (a<b)<c or a<(b<c).
!= is a comparison operator like <, not an arithmetic operator like + 
(or logical xor). If one has 0/1 or True/False values, we have 
arithmetic xor already, ^, which works as expected.

 >>> (a^b)^c
False
 >>> a^b^c
False

Terry Jan Reedy



From scriptlearner at gmail.com  Sat Jul 25 13:32:06 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Sat, 25 Jul 2009 10:32:06 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
Message-ID: <923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>

First of all, let me say thank you to all of you.  I have asked many
questions (some of them are dump questions), and you have kindly
helped me.  I am not going to reply every message to say thank-you
since that would be annoying for such group with such high daily
traffics.  Thank you very much.

Let's get back to topic of this message.
Here's how I have implemented it so far, and I am taking the queue of
work load items approach.
In my child thread, I will keep checking for available work load item
until a duration is reached.
#inside the child#
        while endTime > time.time():
            try:
                 item = self.q.get(True, 3)
            except Queue.Empty:  #what's wrong?  AttributeError: class
Queue has no attribute 'Empty'
                 print 'cant find any work load item, so lets wait and
try again later'
                 time.sleep(1) #wait and then check again
                 continue
            except:
                 print "Unexpected error:", sys.exc_info()[0]
                 raise
            #do the real work with load item

In my parent thread, I will initialize X (depending on a cfg file)
child threads and keep adding load items to a shared q until the
duration is reached.
#inside the parent#
        callCounter = 0
        workers = [] #a list of child threads
        totalWorkers = 250
        endTime = time.time() + duration
        for i in range(totalWorkers):
            w = Worker(q, duration, i)
            w.start() #worker, do your job now!
            workers.append(w)

        while endTime > time.time():
            time.sleep(1)
                q.put(getWorkloadItem()) #add workload itmes
                callCounter += 1 #actually can we guarantee that the
call will be sent??
                                 #should we ask each child to report
the number of calls they make?

        for i in range(totalWorkers):
            workers[i].join()    # Wait for the child threads to
finish


Overall, it seems to be working now.  Though, I still have a couple of
problems to resolve.
1. I got the following error for the codes that attempt to catch Empty
Queue exception.  What's the right way to use it?
    except Queue.Empty:
AttributeError: class Queue has no attribute 'Empty'

2. What's the best way to have each child thread to report the number
of requests they send when they are done?  To add the numbers to
another queue?

3. I will need to do some logging for response time as well as some
response contents.  I have two choices, one big log file for all
threads (both child and parent), and one log file for each thread.
Given the fact that I may have to log tons of data, I think opening
and maintaining a bunch of smaller logs may be better than dealing
with a big one (it may grow very fast).  Is there any best prastice
for logging in Python?  If I change my mind and go with one big log
file (pass it to each thread), is there anything I should be aware of
for multi-thread access (writting) to the same log file?

Again, thank you.


From albert at spenarnc.xs4all.nl  Sat Jul 25 14:01:33 2009
From: albert at spenarnc.xs4all.nl (Albert van der Horst)
Date: 25 Jul 2009 18:01:33 GMT
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
	<02746997$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3457.1248158525.8015.python-list@python.org>
Message-ID: <kncnel.g2y@spenarnc.xs4all.nl>

In article <mailman.3457.1248158525.8015.python-list at python.org>,
Jack Diederich  <jackdied at gmail.com> wrote:
>On Mon, Jul 20, 2009 at 10:00 AM, Steven
>D'Aprano<steve at remove-this-cybersource.com.au> wrote:
>> On Mon, 20 Jul 2009 09:34:24 +0000, Sion Arrowsmith wrote:
>>
>>> Terry Reedy =A0<tjreedy at udel.edu> wrote:
>>>>Sion Arrowsmith wrote:
>>>>> Jack Diederich =A0<jackdied at gmail.com> wrote:
>>>>>> It isn't an OrderedDict thing, it is a comparison thing. =A0Two regul=
>ar
>>>>>> dicts also raise an error if you try to LT them.
>>>>> Python 2.5.2
>>>>>>>> d1 =3D dict((str(i), i) for i in range (10)) d2 =3D dict((str(i), i=
>)
>>>>>>>> for i in range (20)) d1 < d2
>>>>> True
>>>>Try reversing the definitions of d1 and d2. The dicts are probably being
>>>>compared by id (address), which is the 2.x CPython default.
>>>
>>> Like this?
>>>
>>>>>> d1 =3D dict((str(i), i) for i in range (20))
>>>>>> d2 =3D dict((str(i), i) for i in range (10))
>>>>>> d1 < d2
>>> False
>>>>>> id(d1) < id(d2)
>>> True
>>>
>>> I didn't know that comparison for anything other than equality defaulted
>>> to using id. That really is rather broken, and I'm glad 3.0 fixed it.
>>
>>
>> I don't think comparisons other than equality use id. That would be
>> rather insane. If anyone can demonstrate such comparisons in a built-in
>> or standard library class, I'd like to see it.
>>
>>
>> For the record, dicts have been comparable with < and > since at least
>> Python 1.5:
>>
>> $ python1.5
>> Python 1.5.2 (#1, Apr =A01 2009, 22:55:54) =A0[GCC 4.1.2 20070925 (Red Ha=
>t
>> 4.1.2-27)] on linux2
>> Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>>>>
>>>>> {1: 'a', 2: 'b'} < {2: 'b', 3: 'a'}
>> 1
>>
>>
>> Reading the docs:
>>
>> http://docs.python.org/library/stdtypes.html#comparisons
>> http://docs.python.org/library/stdtypes.html#mapping-types-dict
>>
>> I can only suggest that dicts compare in an arbitrary but consistent
>> fashion.
>
>I should have specified 3.x but since we were talking about
>OrderedDicts (only in 3.1) I didn't say it explicitly.   Earlier
>versions of python were very permissive with comparisons -- it was
>rare that any cmp() raised an error and the ultimate fallback was on
>the object's id.  This is one of the non-backwards compatible changes
>in 3k.  Now comparing two of the same thing that don't have an obvious
>ordering is an error.  Is a dict "greater than" if it has a larger
>size?  if its max key is larger?  what does "max key" mean when the
>keys aren't even comparable?.  Comparing things that aren't extremely
>similar is an error now also.

With regard to < and > you are right.
But I think there is a sensible == w.r.t. dict's.
It is to mean that for each key   dict1(key) == dict2(key)
(implying that their key set must be the same)

[I could have used that for one of the euler problems.
You have a 4 by 4 field containing a red or blue square.
That is naturally a mapping of (1,1) ..(4,4) tuples to one
of the objects `blue' `red'. After moving a square you
want to know whether this is a map you already have encountered.]

>
>-Jack


--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst



From kawenks at gmail.com  Sat Jul 25 14:04:45 2009
From: kawenks at gmail.com (allan)
Date: Sat, 25 Jul 2009 11:04:45 -0700 (PDT)
Subject: Form/Template Fill-in the blanks
Message-ID: <4b77a992-370d-4879-88a0-fdd6a23f7c5d@p10g2000prm.googlegroups.com>

I'm attempting to create a generic python script that will take an EDI
document specification and a database of transactions and be able to
generate a raw EDI file (ansi X12).

I'm looking for ideas on how best to use the strengths of Python to
implement this. I've initially tackled the EDI 812 specifications and
narrowed this down to a specific implementation by a company. This
narrowed down version is what I want to achieve for output. But I want
the script to be generic enough such that I can plug-in another EDI
specification + a database transaction set and it will output the
proper raw file accordingly.

My initial thought was to use:
1. .ini files to declare the EDI configuration
2. Use SQLAlchemy as ORB to simplify access to database objects.

INI file configuration:
* A "root" INI file indicates other INI files that define each segment
of the EDI document.
* Each segment INI defines the data elements of each segment and the
behavior of the segment (one instance or multiple-instance as in a
loop, sequence order, segment code, etc.)
* Specify data elements as either constant, system function (like
datetime), database field or object method (object being the
segment's)
* Load all the ini configuration into a "template" object. Each
segment ini maps to its own segment object.

DB using SQLAlchemy
Gather a Trading Partner data and Credit Transaction (EDI 812
remember?) into one dictionary object
Gather Credit Transaction details into another dictionary object where
it can generate the multiple instance segments

The heart of the matter is how to fuse together the template and the
data from the dictionary objects efficiently. It should be generic
enough to take another set of data dictionary and another template to
generate a completely new EDI document.

I'm stuck at this fusing together thing. Is this a good approach? Is
there an easier to implement approach?

Comments, suggestions, questions please.

Allan


From piet at cs.uu.nl  Sat Jul 25 14:18:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sat, 25 Jul 2009 20:18:46 +0200
Subject: Why aren't OrderedDicts comparable with < etc?
References: <b760369e-605a-4fac-aaaa-4f143be5866e@v20g2000yqm.googlegroups.com>
	<ASW8m.3332$Tk2.91@newsfe21.ams2>
	<02746997$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3457.1248158525.8015.python-list@python.org>
	<kncnel.g2y@spenarnc.xs4all.nl>
Message-ID: <m2y6qcd3sp.fsf@cs.uu.nl>

>>>>> Albert van der Horst <albert at spenarnc.xs4all.nl> (AvdH) wrote:

>AvdH> With regard to < and > you are right.
>AvdH> But I think there is a sensible == w.r.t. dict's.
>AvdH> It is to mean that for each key   dict1(key) == dict2(key)
>AvdH> (implying that their key set must be the same)

>AvdH> [I could have used that for one of the euler problems.
>AvdH> You have a 4 by 4 field containing a red or blue square.
>AvdH> That is naturally a mapping of (1,1) ..(4,4) tuples to one
>AvdH> of the objects `blue' `red'. After moving a square you
>AvdH> want to know whether this is a map you already have encountered.]

So what's the problem?

piet$ python3
Python 3.1 (r31:73578, Jun 27 2009, 21:49:46) 
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from collections import OrderedDict
>>> a = OrderedDict()
>>> b = OrderedDict()
>>> a[1]=2
>>> b[1]=2
>>> a[3]=4
>>> b[3]=4
>>> a==b
True
>>> b[5]=6
>>> a==b
False
>>> d1 = dict((str(i), i) for i in range (10))
>>> d2 = dict((str(i), i) for i in range (10))
>>> d1 == d2
True

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From constant.beta at gmail.com  Sat Jul 25 14:30:54 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Sat, 25 Jul 2009 11:30:54 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
Message-ID: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>

Hi,

Is there a way to tell if a generator has been exhausted using pure
Python code? I've looked at CPython sources and it seems that
something like "active"/"exhausted" attribute on genobject is missing
from the API. For the time being I am using a simple C extension to
look at f_stacktop pointer of the generator frame, which seems to
differentiate active generators from exhausted ones. See
http://bazaar.launchpad.net/~ruby/pythoscope/support-python2.3/annotate/286/pythoscope/_util.c#L16
for complete source code.

I may be missing something obvious here. Is there a better way to tell
if a given generator object is still active or not?

Cheers,
mk


From python at mrabarnett.plus.com  Sat Jul 25 14:39:24 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sat, 25 Jul 2009 19:39:24 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
Message-ID: <4A6B515C.9040803@mrabarnett.plus.com>

scriptlearner at gmail.com wrote:
> First of all, let me say thank you to all of you.  I have asked many
> questions (some of them are dump questions), and you have kindly
> helped me.  I am not going to reply every message to say thank-you
> since that would be annoying for such group with such high daily
> traffics.  Thank you very much.
> 
> Let's get back to topic of this message.
> Here's how I have implemented it so far, and I am taking the queue of
> work load items approach.
> In my child thread, I will keep checking for available work load item
> until a duration is reached.
> #inside the child#
>         while endTime > time.time():
>             try:
>                  item = self.q.get(True, 3)
>             except Queue.Empty:  #what's wrong?  AttributeError: class
> Queue has no attribute 'Empty'
>                  print 'cant find any work load item, so lets wait and
> try again later'
>                  time.sleep(1) #wait and then check again
>                  continue
>             except:
>                  print "Unexpected error:", sys.exc_info()[0]
>                  raise
>             #do the real work with load item
> 
> In my parent thread, I will initialize X (depending on a cfg file)
> child threads and keep adding load items to a shared q until the
> duration is reached.
> #inside the parent#
>         callCounter = 0
>         workers = [] #a list of child threads
>         totalWorkers = 250
>         endTime = time.time() + duration
>         for i in range(totalWorkers):
>             w = Worker(q, duration, i)
>             w.start() #worker, do your job now!
>             workers.append(w)
> 
>         while endTime > time.time():
>             time.sleep(1)
>                 q.put(getWorkloadItem()) #add workload itmes
>                 callCounter += 1 #actually can we guarantee that the
> call will be sent??
>                                  #should we ask each child to report
> the number of calls they make?
> 
>         for i in range(totalWorkers):
>             workers[i].join()    # Wait for the child threads to
> finish
> 
> 
> Overall, it seems to be working now.  Though, I still have a couple of
> problems to resolve.
> 1. I got the following error for the codes that attempt to catch Empty
> Queue exception.  What's the right way to use it?
>     except Queue.Empty:
> AttributeError: class Queue has no attribute 'Empty'
> 

The exception 'Empty' belongs to the module, not the class. Try
importing as:

     from Queue import Queue, Empty

> 2. What's the best way to have each child thread to report the number
> of requests they send when they are done?  To add the numbers to
> another queue?
> 
Why not? :-)

> 3. I will need to do some logging for response time as well as some
> response contents.  I have two choices, one big log file for all
> threads (both child and parent), and one log file for each thread.
> Given the fact that I may have to log tons of data, I think opening
> and maintaining a bunch of smaller logs may be better than dealing
> with a big one (it may grow very fast).  Is there any best prastice
> for logging in Python?  If I change my mind and go with one big log
> file (pass it to each thread), is there anything I should be aware of
> for multi-thread access (writting) to the same log file?
> 
> Again, thank you.

If you like threads then you could put the log items into a queue and
have another thread writing them to the logfile. :-)

BTW, do you really need 250 threads? Seems like a lot.

I notice that you stop putting items into the queue when endTime is
reached and also the threads terminate when endTime is reached. If items
are put into the queue faster than they're taken out (or an item is put
in just before endTime) then there might still be unprocessed items in
the queue at endTime.


From rknop at pobox.com  Sat Jul 25 14:57:55 2009
From: rknop at pobox.com (Rob Knop)
Date: Sat, 25 Jul 2009 13:57:55 -0500
Subject: RSA cryptography between Python and Java
Message-ID: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>


I've created an RSA key in Java.  I have exported the public key by
making it into a X509EncodedKeySpec and spitting out the result of
getEncoded().

I want to use this public key to encode something in python that I will
send to Java, and then decode in Java with the corresponding private
key.

Are there any python libraries that will take a public key in this
format and do RSA encoding on it?

-- 
--Rob Knop
  E-mail:    rknop at pobox.com
  Home Page: http://www.pobox.com/~rknop/
  Blog:      http://www.sonic.net/~rknop/blog/


From http  Sat Jul 25 15:01:07 2009
From: http (Paul Rubin)
Date: 25 Jul 2009 12:01:07 -0700
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
Message-ID: <7xocr8si30.fsf@ruckus.brouhaha.com>

Rob Knop <rknop at pobox.com> writes:
> Are there any python libraries that will take a public key in this
> format and do RSA encoding on it?

Try www.trevp.com/tlslite


From rylesny at gmail.com  Sat Jul 25 15:11:23 2009
From: rylesny at gmail.com (ryles)
Date: Sat, 25 Jul 2009 12:11:23 -0700 (PDT)
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
References: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>
	<m2iqhgex8w.fsf@cs.uu.nl>
Message-ID: <ef5b3dbe-92ab-45cb-a150-f8a921b68c71@r24g2000vbn.googlegroups.com>

On Jul 25, 8:57?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> ryles <ryle... at gmail.com> (r) wrote:
> >r> According tohttp://www.python.org/doc/essays/packages.html:
> >r> "The import statement first tests whether the item is defined in the
> >r> package; if not, it assumes it is a module and attempts to load it."
> >r> However, I've noticed that once a module is imported using the
> >r> `from pkg import mod' syntax, if its name is deleted from the
> >r> package namespace then subsequent imports with `from' will fail.
>
> This is incorrectly stated. Also on the initial import it will fail, not
> just on subsequent imports.
>
> piet$ python
> Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39)
> [GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
> Type "help", "copyright", "credits" or "license" for more information.>>> from pkg import _impl
>
> _impl # this is from a print statement in _impl to show that it did import
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> ImportError: cannot import name _impl
>

Well, since __init__.py is executed first, I would regard it as
causing the initial (successful) import, and yours being the
subsequent one, so that the "initial" import does not fail, the
subsequent one does. Wording aside, though, I think we are on the same
page here.

>
> According to the documentation
> <http://docs.python.org/library/functions.html#__import__> the statement
> from pkg import _impl
>
> _temp = __import__('pkg', globals(), locals(), ['_impl'], -1)
> _impl = _temp._impl
>
> This fails because _temp (the imported module) doesn't have a binding
> for _impl because you deleted it.

But supposing we hadn't deleted it, and __init__.py didn't import
_impl, there would still be no binding. Yet the importer would still
import and make the module available (presumably it "knows" to do this
since it was not already in sys.modules). The question really is that
since in our example pkg._impl is still in sys.modules, why won't the
importer add it to the pkg namespace again as it previous had? I would
imagine this is either by design, or is a case that was never
considered.

> for _impl because you deleted it. By the way, if you have a `normal'
> package that doesn't do anything with the name _impl, after the import
> the pkg module namespace will have got a binding for _impl although it is not
> in your code. It will have been put there by the import code.

Yes, this was noted further down in the original post with an example.


From tom.sully at gmx.com  Sat Jul 25 15:27:37 2009
From: tom.sully at gmx.com (Tom)
Date: Sat, 25 Jul 2009 20:27:37 +0100
Subject: Removing newlines from string on windows (without replacing)
Message-ID: <1248550057.5509.86.camel@ubuntu.ubuntu-domain>

This is my first post to this mailing list, so hi :)

I have an annoying problem. While I mainly use Linux when I distribute
this program to friends and on the internet, it'll get used on Windows.
So, I tested my python program on my Windows Vista dual boot, running
the same version of python (2.6) as my Linux, and got an error at the
following code.

s = sauce.replace("\n", "")

Sauce is a string, read from a file, that I need to remove newlines
from. This code works fine in Linux, but not in Windows. rstrip("\n")
won't work for me, so anybody know how to get this working on Windows?

Thanks! :D

--print "Tom"



From rhodri at wildebst.demon.co.uk  Sat Jul 25 15:53:51 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sat, 25 Jul 2009 20:53:51 +0100
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com>
	<7ct4b8F29mednU1@mid.uni-berlin.de> <24654439.post@talk.nabble.com>
Message-ID: <op.uxm2v1t6a8ncjz@gnudebst>

On Sat, 25 Jul 2009 03:50:54 +0100, Dr. Phillip M. Feldman  
<pfeldman at verizon.net> wrote:

>
> Here's a simple-minded example:
>
> def dumbfunc(xs):
>    for x in xs:
>       print x
>
> This function works fine if xs is a list of floats, but not if it is  
> single
> float.  It can be made to work as follows:
>
> def dumbfunc(xs):
>    if isinstance(xs,(int,float,complex)): xs= [xs]
>    for x in xs:
>       print x
>
> Having to put such extra logic into practically every function is one of  
> the
> annoying things about Python.

If you persist in treating <language 1> as if it was <language 2>, then
your code will always be ugly, and often buggy.  Unless we're talking
natural languages, in which case Yoda-like you will sound.

Fundamentally, your problem is your assertion that it is reasonable to
allow users to treat a single object as if it were wrapped in a list.
In Python, it is not reasonable, for the reasons that you are spending
so much time complaining about.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From tack at urandom.ca  Sat Jul 25 16:00:02 2009
From: tack at urandom.ca (Jason Tackaberry)
Date: Sat, 25 Jul 2009 16:00:02 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
Message-ID: <1248552002.4390.2.camel@willow>

On Sat, 2009-07-25 at 11:30 -0700, Michal Kwiatkowski wrote:
> Is there a way to tell if a generator has been exhausted using pure
> Python code? I've looked at CPython sources and it seems that

Upon a cursory look, after a generator 'gen' is exhausted (meaning
gen.next() has raised StopIteration), it seems that gen.gi_frame will be
None.

Cheers,
Jason.	



From rknop at pobox.com  Sat Jul 25 16:08:17 2009
From: rknop at pobox.com (Rob Knop)
Date: Sat, 25 Jul 2009 15:08:17 -0500
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com>
Message-ID: <q3z63dgv83y.fsf@antonio.tmnwh.net>

Paul Rubin <http://phr.cx at NOSPAM.invalid> writes:

> www.trevp.com/tlslite

Thanks, but that looks like a library for setting up a secure connection
between two ends.  What I need is the ability to encrypt with a public
key in Python, where that public key was generated in Java as described,
and where the cipertext can later be decrypted with the corresponding
secret key in Java.

-- 
--Rob Knop
  E-mail:    rknop at pobox.com
  Home Page: http://www.pobox.com/~rknop/
  Blog:      http://www.sonic.net/~rknop/blog/


From rhodri at wildebst.demon.co.uk  Sat Jul 25 16:08:54 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sat, 25 Jul 2009 21:08:54 +0100
Subject: Removing newlines from string on windows (without replacing)
In-Reply-To: <1248550057.5509.86.camel@ubuntu.ubuntu-domain>
References: <1248550057.5509.86.camel@ubuntu.ubuntu-domain>
Message-ID: <op.uxm3k4z1a8ncjz@gnudebst>

On Sat, 25 Jul 2009 20:27:37 +0100, Tom <tom.sully at gmx.com> wrote:

> This is my first post to this mailing list, so hi :)
>
> I have an annoying problem. While I mainly use Linux when I distribute
> this program to friends and on the internet, it'll get used on Windows.
> So, I tested my python program on my Windows Vista dual boot, running
> the same version of python (2.6) as my Linux, and got an error at the
> following code.
>
> s = sauce.replace("\n", "")

What error?  (I don't let Vista in the house.)

> Sauce is a string, read from a file, that I need to remove newlines
> from. This code works fine in Linux, but not in Windows. rstrip("\n")
> won't work for me, so anybody know how to get this working on Windows?

Why won't rstrip("\n") work?  Is rstrip() OK instead, or does trailing
whitespace matter to you?

To provide a partial answer, your problem probably lies in the different
ways Windows and Linux treat ends of lines.  Under Linux, "\n" is the
line terminator.  Under Windows, it's "\r\n".  If you opened your file
in "byte mode" with open("myfile.txt", "rb"), you will be given all the
bytes in the file, including those extra "\r" characters on Windows.  If
you open your file in text mode with open("myfile.txt, "r") instead, the
line endings are converted to "\n" on both Windows and Linux.

If my crystal ball has proved faulty, giving us more details will help
get a more sensible answer.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From http  Sat Jul 25 16:10:43 2009
From: http (Paul Rubin)
Date: 25 Jul 2009 13:10:43 -0700
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com>
	<q3z63dgv83y.fsf@antonio.tmnwh.net>
Message-ID: <7xiqhgmsl8.fsf@ruckus.brouhaha.com>

Rob Knop <rknop at pobox.com> writes:
> > www.trevp.com/tlslite
> 
> Thanks, but that looks like a library for setting up a secure connection
> between two ends.  What I need is the ability to encrypt with a public
> key in Python, where that public key was generated in Java as described,
> and where the cipertext can later be decrypted with the corresponding
> secret key in Java.

Yes, I think that library has the function that you want.  It's just
X509 DER encoding.


From constant.beta at gmail.com  Sat Jul 25 16:20:11 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Sat, 25 Jul 2009 13:20:11 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<mailman.3715.1248552511.8015.python-list@python.org>
Message-ID: <2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>

On Jul 25, 10:00?pm, Jason Tackaberry <t... at urandom.ca> wrote:
> On Sat, 2009-07-25 at 11:30 -0700, Michal Kwiatkowski wrote:
> > Is there a way to tell if a generator has been exhausted using pure
> > Python code? I've looked at CPython sources and it seems that
>
> Upon a cursory look, after a generator 'gen' is exhausted (meaning
> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
> None.

Only in Python 2.5 or higher though. I need to support Python 2.3 and
2.4 as well, sorry for not making that clear in the original post.

Cheers,
mk


From news123 at free.fr  Sat Jul 25 16:29:29 2009
From: news123 at free.fr (News123)
Date: Sat, 25 Jul 2009 22:29:29 +0200
Subject: available formats and params for Image.save()
In-Reply-To: <mailman.3647.1248428867.8015.python-list@python.org>
References: <4a6833dd$0$22599$426a34cc@news.free.fr>
	<mailman.3647.1248428867.8015.python-list@python.org>
Message-ID: <4a6b6b29$0$435$426a74cc@news.free.fr>

Thanks a lot Gabriel,

Your answer is perfect.

I was only looking in part II of the PIL manual and overlooked the
Appendix :-(.

I also apreciate
Image.ID , Image.SAVE , Image.OPEN

I saw them when typing
dir Image
but I never had the idea of calling Image.init() first

bye

N




Gabriel Genellina wrote:
> En Thu, 23 Jul 2009 06:56:45 -0300, News123 <news123 at free.fr> escribi?:
> 
>> Somehow I have difficulties reading the documentation for PIL (Image)
>>
>> Is there an easy way to know which formats are supported and what their
>> names are?
> 
> py> import PIL
> py> from PIL import Image
> py> Image.ID
> []
> py> Image.init()
> py> Image.ID
> ['PNG', 'ARG', 'BMP', 'BUFR', 'CUR', 'PCX', 'DCX', 'EPS', 'FITS', 'FLI',
> 'FPX',
> 'GBR', 'GIF', 'GRIB', 'HDF5', 'ICNS', 'ICO', 'IM', 'IMT', 'IPTC',
> 'JPEG', 'MCIDA
> S', 'TIFF', 'MIC', 'MPEG', 'MSP', 'PCD', 'PIXAR', 'PPM', 'PSD', 'SGI',
> 'SPIDER',
>  'SUN', 'TGA', 'WBMP', 'WMF', 'XBM', 'XPM', 'XVTHUMB']
> py> Image.OPEN.keys()
> ['PCX', 'ICNS', 'HDF5', 'SUN', 'MIC', 'EPS', 'MSP', 'FLI', 'FITS',
> 'GBR', 'WBMP'
> , 'PCD', 'PIXAR', 'BUFR', 'PPM', 'WMF', 'SGI', 'BMP', 'TGA', 'DCX',
> 'ICO', 'CUR'
> , 'XPM', 'TIFF', 'JPEG', 'SPIDER', 'GIF', 'GRIB', 'IM', 'IMT', 'IPTC',
> 'FPX', 'X
> BM', 'MPEG', 'PSD', 'ARG', 'XVTHUMB', 'PNG', 'MCIDAS']
> py> Image.SAVE.keys()
> ['XBM', 'PCX', 'SPIDER', 'HDF5', 'TIFF', 'BUFR', 'EPS', 'JPEG', 'MSP',
> 'GRIB', '
> GIF', 'BMP', 'IM', 'PPM', 'PDF', 'FITS', 'PALM', 'WBMP', 'WMF', 'PNG']
> 
>> Is there an easy way to know which parameters are supported by
>> Image.save(). How can I list them where are they documented?
> 
> That depends on the format being used. The PIL handbook lists the
> standard formats used and their parameters:
> http://www.pythonware.com/library/pil/handbook/index.htm
> 
>> I'm at a complete loss at finding out what parameters the save function
>> accepts for saving a JPG file or a PNG file
> 
> http://www.pythonware.com/library/pil/handbook/format-jpeg.htm
> 


From mwawrzyczek at gmail.com  Sat Jul 25 16:33:01 2009
From: mwawrzyczek at gmail.com (marekw2143)
Date: Sat, 25 Jul 2009 13:33:01 -0700 (PDT)
Subject: Adding method from one class to another class or to instance of 
	another class
References: <6d9d960e-7f05-4fd8-a0a8-56bea4be0c45@e27g2000yqm.googlegroups.com>
	<mailman.3678.1248463055.8015.python-list@python.org>
Message-ID: <953308c3-671f-4604-9562-d37767e600a4@g6g2000vbr.googlegroups.com>

Thanks for your responses. im_func is all I need. I considered
subclassing, wchih is more easy to extend, but I needed some quick way
to add a method to another class.

Regards,
Marek


From robert.kern at gmail.com  Sat Jul 25 16:57:23 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sat, 25 Jul 2009 15:57:23 -0500
Subject: len() should always return something
In-Reply-To: <24654439.post@talk.nabble.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<24654439.post@talk.nabble.com>
Message-ID: <h4frjl$2vm$1@ger.gmane.org>

On 2009-07-24 21:50, Dr. Phillip M. Feldman wrote:
> Here's a simple-minded example:
>
> def dumbfunc(xs):
>     for x in xs:
>        print x
>
> This function works fine if xs is a list of floats, but not if it is single
> float.  It can be made to work as follows:
>
> def dumbfunc(xs):
>     if isinstance(xs,(int,float,complex)): xs= [xs]
>     for x in xs:
>        print x
>
> Having to put such extra logic into practically every function is one of the
> annoying things about Python.

I have spent the last ten years writing scientific code in Python (i.e. that 
which otherwise might be written in Matlab), and I can guarantee you that you do 
not need to put such extra logic in practically every function. Even when 
naively translating code from Matlab, it's not often necessary.

By the way, are you familiar with numpy? If you are converting code from Matlab, 
you will almost certainly need it. We have a number of functions that make these 
kinds of operations easy when they are in fact necessary. For example, we have 
isscalar() and atleast_1d().

   def dumbfunc(xs):
     xs = numpy.atleast_1d(xs)
     for x in xs:
       print x

http://numpy.scipy.org/

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From robert.kern at gmail.com  Sat Jul 25 16:59:30 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sat, 25 Jul 2009 15:59:30 -0500
Subject: len() should always return something
In-Reply-To: <7cvs3fF24hjh7U1@mid.uni-berlin.de>
References: <24639361.post@talk.nabble.com>
	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>
	<7cvs3fF24hjh7U1@mid.uni-berlin.de>
Message-ID: <h4frnj$2vm$2@ger.gmane.org>

On 2009-07-25 02:55, Diez B. Roggisch wrote:
> Dr. Phillip M. Feldman schrieb:
>> Here's a simple-minded example:
>>
>> def dumbfunc(xs):
>> for x in xs:
>> print x
>>
>> This function works fine if xs is a list of floats, but not if it is
>> single
>> float. It can be made to work as follows:
>>
>> def dumbfunc(xs):
>> if isinstance(xs,(int,float,complex)): xs= [xs]
>> for x in xs:
>> print x
>>
>> Having to put such extra logic into practically every function is one
>> of the
>> annoying things about Python.
>
> And where comes "len(xs)" into play here? What you want is iteration
> over scalars.

He explained in another post that iteration is another feature along the same 
lines that he would want for scalars.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From lie.1296 at gmail.com  Sat Jul 25 18:30:30 2009
From: lie.1296 at gmail.com (Lie Ryan)
Date: Sun, 26 Jul 2009 08:30:30 +1000
Subject: Failed Regression Test: What socket.gethostname() is supposed to
	return?
Message-ID: <h4g127$gai$1@ger.gmane.org>

In my laptop, socket.gethostname() returned my username, and causing one
of python's "make test" regression test to error (test_socket):

======================================================================
ERROR: testSockName (test.test_socket.GeneralModuleTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File
"/var/tmp/portage/dev-lang/python-2.5.4-r3/work/Python-2.5.4/Lib/test/test_socket.py",
line 456, in testSockName
    my_ip_addr = socket.gethostbyname(socket.gethostname())
gaierror: (-2, 'Name or service not known')

----------

since on my system socket.gethostname() returns 'lieryan', and since
socket.gethostbyname('lieryan') does not resolve to anything; the test
becomes an error.

My system is Gentoo, but I think this also happened on Ubuntu (still on
this laptop). The trunk failed in similar manner.

Do I have a misconfigured system or is the test faulty?

For convenience, the relevant test code (taken from trunk):

=======================
def testSockName(self):
    # Testing getsockname()
    port = self._get_unused_port()
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.bind(("0.0.0.0", port))
    name = sock.getsockname()
    # XXX(nnorwitz): http://tinyurl.com/os5jz seems to indicate
    # it reasonable to get the host's addr in addition to 0.0.0.0.
    # At least for eCos.  This is required for the S/390 to pass.
    my_ip_addr = socket.gethostbyname(socket.gethostname())
    self.assertTrue(name[0] in ("0.0.0.0", my_ip_addr), '%s invalid' %
name[0])
    self.assertEqual(name[1], port)
=======================


lieryan at lieryan ~/Desktop/pythontrunk/trunk $ ./python -m test.regrtest
test_socket
Could not find '/home/lieryan/Desktop/pythontrunk/trunk/Lib/test' in
sys.path to remove it
test_socket
test test_socket failed -- Traceback (most recent call last):
  File
"/home/lieryan/Desktop/pythontrunk/trunk/Lib/test/test_socket.py", line
493, in testSockName
    my_ip_addr = socket.gethostbyname(socket.gethostname())
gaierror: [Errno -2] Name or service not known

1 test failed:
    test_socket

I tracked the code for socket.gethostname() and socket.gethostbyname()
and found that they are simply a wrapper for gethostname() from #import
<unistd.h> (http://linux.die.net/man/2/gethostname) and gethostbyname()
from #import <netdb.h> (http://linux.die.net/man/3/gethostbyname). A
simple test in C found that the C's equivalent to
gethostbyname(gethostname()) returns a null pointer (used to indicate
error, per documentation).

So, the question is: what is socket.gethostname() is supposed to return
that will be a valid argument for socket.gethostbyname()?

PS: I found an MSDN article by Microsoft stating that
gethostbyname(gethostname) is guaranteed to always succeed
(http://msdn.microsoft.com/en-us/library/ms738527(VS.85).aspx); is this
guarantee also true in linux?



From marcusw at cox.net  Sat Jul 25 18:42:26 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Sat, 25 Jul 2009 18:42:26 -0400
Subject: len() should always return something
In-Reply-To: <m2eis4etyb.fsf@cs.uu.nl>
References: <24639361.post@talk.nabble.com>
	<mailman.3645.1248418956.8015.python-list@python.org>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<m2tz11fatt.fsf@cs.uu.nl>
	<027af2b3$0$5185$c3e8da3@news.astraweb.com>
	<m2eis4etyb.fsf@cs.uu.nl>
Message-ID: <h4g1ok$2tj2$1@adenine.netfront.net>

On 7/25/2009 10:08 AM, Piet van Oostrum wrote:
>>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:
> 
>> SD> Ambiguity essentially boils down to being unable to reasonably predict 
>> SD> the expectation of the coder. I say "reasonably", because if you allow 
>> SD> unreasonable situations, everything is "ambiguous":
> 
> That's for me the reason that len(42) is ambiguous. The OP apparently
> had 1 as expectation, whereas my first thought was the minimal number of
> bits to represent the number and 7.5 million came later :=). The number
> of bits I certainly find reasonable, and I would find the number of
> decimal digits equally reasonable. More so than 1, actually. 1 as the
> length of an int doesn't give any information.
Well, for my two cents, I will say that the number of binary bits or 
decimal digits is certainly the most sensible return value, and that the 
former is the most useful, because the latter can be got with 
len(str(42)). However, the former can also be (/slightly/ less)easily 
got with len(bin(42))-2...

I also think that "Explicit is better than implicit." says that there 
should be no return value in this case, as any return value would be 
implicit.

Marcus


From ben+python at benfinney.id.au  Sat Jul 25 19:10:40 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sun, 26 Jul 2009 09:10:40 +1000
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
Message-ID: <877hxw4avj.fsf@benfinney.id.au>

Michal Kwiatkowski <constant.beta at gmail.com> writes:

> I may be missing something obvious here. Is there a better way to tell
> if a given generator object is still active or not?

    foo = the_generator_object
    try:
        do_interesting_thing_that_needs(foo.next())
    except StopIteration:
        generator_is_exhausted()

In other words, don't LBYL, because it's EAFP. Whatever you need to do
that requires the next item from the generator, do that; you'll get a
specific exception if the generator is exhausted.

-- 
 \      ?Courteous and efficient self-service.? ?caf?, southern France |
  `\                                                                   |
_o__)                                                                  |
Ben Finney


From max at alcyone.com  Sat Jul 25 19:21:39 2009
From: max at alcyone.com (Erik Max Francis)
Date: Sat, 25 Jul 2009 16:21:39 -0700
Subject: len() should always return something
In-Reply-To: <027a9f1a$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>

Steven D'Aprano wrote:
> But it's not "practically every function". It's hardly any function at 
> all -- in my code, I don't think I've ever wanted this behavior. I would 
> consider it an error for function(42) and function([42]) to behave the 
> same way. One is a scalar, and the other is a vector -- they're different 
> things, it's poor programming practice to treat them identically.
> 
> (If Matlab does this, so much the worse for Matlab, in my opinion.)

There's actually good reason to do this in heavily matrix-oriented 
specialized languages; there are numerous applications where scalars and 
1x1 matrices are mathematically equivalent.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   Gods are born and die, but the atom endures.
    -- Alexander Chase


From clp2 at rebertia.com  Sat Jul 25 19:30:44 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 25 Jul 2009 16:30:44 -0700
Subject: len() should always return something
In-Reply-To: <04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
Message-ID: <50697b2c0907251630s6e4f7e0en6876b3609eb4fa5@mail.gmail.com>

On Sat, Jul 25, 2009 at 4:21 PM, Erik Max Francis<max at alcyone.com> wrote:
> Steven D'Aprano wrote:
>>
>> But it's not "practically every function". It's hardly any function at all
>> -- in my code, I don't think I've ever wanted this behavior. I would
>> consider it an error for function(42) and function([42]) to behave the same
>> way. One is a scalar, and the other is a vector -- they're different things,
>> it's poor programming practice to treat them identically.
>>
>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
>
> There's actually good reason to do this in heavily matrix-oriented
> specialized languages; there are numerous applications where scalars and 1x1
> matrices are mathematically equivalent.

The pertinent issue here being that Python, as a language, is neither
matrix-oriented nor special-purpose. :)

Cheers,
Chris
-- 
http://blog.rebertia.com


From davea at ieee.org  Sat Jul 25 20:35:05 2009
From: davea at ieee.org (Dave Angel)
Date: Sat, 25 Jul 2009 20:35:05 -0400
Subject: strange python scripting error
In-Reply-To: <h4fu50$9pe$1@ger.gmane.org>
References: <abdfac9e-979c-446d-9543-33a47cffc6c1@y7g2000yqa.googlegroups.com>	<mailman.3636.1248390216.8015.python-list@python.org>	<c782d9b0-2246-4515-8a4f-807c0299ff0d@s6g2000vbp.googlegroups.com>	<948a21b4-864a-4c9c-9a60-15afd6e8e5b8@r2g2000yqm.googlegroups.com>	<0e4e4eb7-59e3-461b-9d41-9704a88f1d6b@18g2000yqa.googlegroups.com>	<4A6AEA22.1030207@ieee.org>
	<h4fu50$9pe$1@ger.gmane.org>
Message-ID: <4A6BA4B9.5090800@ieee.org>



Dennis Lee Bieber wrote:
> On Sat, 25 Jul 2009 07:18:58 -0400, Dave Angel <davea at ieee.org>
> declaimed the following in gmane.comp.python.general:
>
>   
>> Another thing I'd point out is that some ftp programs will do this 
>> conversion as the file is being sent between a local DOS machine and a 
>> Unix machine on the internet.
>>
>>     
> 	"some ftp programs"?
>
> 	Line end conversion is the whole reason, to my knowledge, for text
> mode transfer, vs binary mode transfer.
>
> <snip>
>
>   
Perhaps I should have said "most ftp programs," or even "all ftp 
programs," but I don't feel qualified to make such a generalization.  In 
any case, I don't currently use such automatic conversion when I'm doing 
transfers because I like to be able to see exactly what's there, and I 
don't have another way to directly examine the remote end.

The FTP I use is an add-on for Firefox (FireFTP), and although it has 
text and "auto" modes, it's buried in the Tools->options menu, and the 
main panel just does a transfer using whichever mode was selected.  
Rather than risking corrupting the (mostly binary) files, I choose to 
use binary mode all the time.

DaveA



From scriptlearner at gmail.com  Sat Jul 25 21:03:37 2009
From: scriptlearner at gmail.com (scriptlearner at gmail.com)
Date: Sat, 25 Jul 2009 18:03:37 -0700 (PDT)
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com> 
	<mailman.3720.1248558305.8015.python-list@python.org>
Message-ID: <96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>

I decided to go with one big log file, which will be shared by all
threads (child and parent).  A log message Queue is used to store all
log entries, and a customized logger thread will get log entries from
the Queue.

#from the logger thread#
    def run(self):
        while self.flag == 1: #if the flag is set to 0, the logger
thread should exit
            try:
                 entry = self.q.get()
            except Empty:
                 self.logger.debug('cant find any log entry')
                 continue
            except:
                 self.logger.error("Unexpected error:", sys.exc_info()
[0])
                 raise
            #do whatever that should be done
        self.logger.info("logger thread done") #should see this
message in log file as well
    def off(self):
        self.logger.info('turning off flag')
        self.flag = 0


#in parent thread#
        logItemQ.put('We are done, lets stop the logger now.')
        time.sleep(1) #it seems that the logger thread cannot exit if
I put a sleep here
        myLog.off() #off is called successfully
        myLog.join()


I put an off method to turn off a flag so the logger thread knows it
should exit.  However, the last log message (the one 'We are done,
lets stop the logger now.') won't be logged if I call myLog.off() and
myLog.join() immediately.  So, I put a time.sleep(1) to make sure the
logger thread has enough time to finish it's job.  Unfortunately, now
the logger thread simply won't exit, and I don't see the message
'logger thread done'.  I can't figure out at which point it hangs,
since I don't any new log entry but the thread simply won't exit.
Am I taking a right approach by using a flag?  Should I lock the flag?


From python at mrabarnett.plus.com  Sat Jul 25 21:30:00 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 26 Jul 2009 02:30:00 +0100
Subject: how can a child thread notify a parent thread its status?
In-Reply-To: <96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
	<mailman.3720.1248558305.8015.python-list@python.org>
	<96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>
Message-ID: <4A6BB198.4040209@mrabarnett.plus.com>

scriptlearner at gmail.com wrote:
> I decided to go with one big log file, which will be shared by all
> threads (child and parent).  A log message Queue is used to store all
> log entries, and a customized logger thread will get log entries from
> the Queue.
> 
> #from the logger thread#
>     def run(self):
>         while self.flag == 1: #if the flag is set to 0, the logger
> thread should exit
>             try:
>                  entry = self.q.get()
>             except Empty:
>                  self.logger.debug('cant find any log entry')
>                  continue
>             except:
>                  self.logger.error("Unexpected error:", sys.exc_info()
> [0])
>                  raise
>             #do whatever that should be done
>         self.logger.info("logger thread done") #should see this
> message in log file as well
>     def off(self):
>         self.logger.info('turning off flag')
>         self.flag = 0
> 
> 
> #in parent thread#
>         logItemQ.put('We are done, lets stop the logger now.')
>         time.sleep(1) #it seems that the logger thread cannot exit if
> I put a sleep here
>         myLog.off() #off is called successfully
>         myLog.join()
> 
> 
> I put an off method to turn off a flag so the logger thread knows it
> should exit.  However, the last log message (the one 'We are done,
> lets stop the logger now.') won't be logged if I call myLog.off() and
> myLog.join() immediately.  So, I put a time.sleep(1) to make sure the
> logger thread has enough time to finish it's job.  Unfortunately, now
> the logger thread simply won't exit, and I don't see the message
> 'logger thread done'.  I can't figure out at which point it hangs,
> since I don't any new log entry but the thread simply won't exit.
> Am I taking a right approach by using a flag?  Should I lock the flag?

self.q.get() will block if the queue is empty, so the Empty exception is
never raised.

What's happening is that the parent thread puts the final message into
the queue, sleeps, and then clears the flag; meanwhile, the logging
thread gets the message, writes it out, checks the flag, which is still
set, and then tries to get the next message. The queue is empty, so the
.get() blocks.

The simplest solution is not to use a flag, but the sentinel trick. The
parent thread can put, say, None into the queue after the last message;
when the logging thread gets None, it knows it should terminate.



From max at alcyone.com  Sat Jul 25 21:47:07 2009
From: max at alcyone.com (Erik Max Francis)
Date: Sat, 25 Jul 2009 18:47:07 -0700
Subject: len() should always return something
In-Reply-To: <mailman.3723.1248564649.8015.python-list@python.org>
References: <24639361.post@talk.nabble.com>
	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
	<mailman.3723.1248564649.8015.python-list@python.org>
Message-ID: <O_idnfu_uNcGKPbXnZ2dnUVZ_tidnZ2d@giganews.com>

Chris Rebert wrote:
> On Sat, Jul 25, 2009 at 4:21 PM, Erik Max Francis<max at alcyone.com> wrote:
>> Steven D'Aprano wrote:
>>> But it's not "practically every function". It's hardly any function at all
>>> -- in my code, I don't think I've ever wanted this behavior. I would
>>> consider it an error for function(42) and function([42]) to behave the same
>>> way. One is a scalar, and the other is a vector -- they're different things,
>>> it's poor programming practice to treat them identically.
>>>
>>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
>> There's actually good reason to do this in heavily matrix-oriented
>> specialized languages; there are numerous applications where scalars and 1x1
>> matrices are mathematically equivalent.
> 
> The pertinent issue here being that Python, as a language, is neither
> matrix-oriented nor special-purpose. :)

Yes.  And I was responding to the comment that such a feature of a 
language would a priori be poor design.  It _isn't_ poor design for 
special purpose languages.  Python isn't one of them, but Matlab _is_.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   More fodder for the new lost generation
    -- Nik Kershaw


From clp2 at rebertia.com  Sat Jul 25 22:39:13 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 25 Jul 2009 19:39:13 -0700
Subject: len() should always return something
In-Reply-To: <O_idnfu_uNcGKPbXnZ2dnUVZ_tidnZ2d@giganews.com>
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
	<mailman.3723.1248564649.8015.python-list@python.org>
	<O_idnfu_uNcGKPbXnZ2dnUVZ_tidnZ2d@giganews.com>
Message-ID: <50697b2c0907251939u4c159290qf700640721e88e3a@mail.gmail.com>

On Sat, Jul 25, 2009 at 6:47 PM, Erik Max Francis<max at alcyone.com> wrote:
> Chris Rebert wrote:
>>
>> On Sat, Jul 25, 2009 at 4:21 PM, Erik Max Francis<max at alcyone.com> wrote:
>>>
>>> Steven D'Aprano wrote:
>>>>
>>>> But it's not "practically every function". It's hardly any function at
>>>> all
>>>> -- in my code, I don't think I've ever wanted this behavior. I would
>>>> consider it an error for function(42) and function([42]) to behave the
>>>> same
>>>> way. One is a scalar, and the other is a vector -- they're different
>>>> things,
>>>> it's poor programming practice to treat them identically.
>>>>
>>>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
>>>
>>> There's actually good reason to do this in heavily matrix-oriented
>>> specialized languages; there are numerous applications where scalars and
>>> 1x1
>>> matrices are mathematically equivalent.
>>
>> The pertinent issue here being that Python, as a language, is neither
>> matrix-oriented nor special-purpose. :)
>
> Yes. ?And I was responding to the comment that such a feature of a language
> would a priori be poor design. ?It _isn't_ poor design for special purpose
> languages. ?Python isn't one of them, but Matlab _is_.

I was agreeing with your point actually. That was what I was trying to
convey in my post. Apparently I wasn't as successful in that regard as
I'd hoped.

- Chris
-- 
http://blog.rebertia.com


From martin at v.loewis.de  Sun Jul 26 00:07:21 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 06:07:21 +0200
Subject: uniicode and executing a process with subprocess.call,
	or os.system
In-Reply-To: <mailman.3381.1247956757.8015.python-list@python.org>
References: <mailman.3381.1247956757.8015.python-list@python.org>
Message-ID: <4a6bd67a$0$7423$9b622d9e@news.freenet.de>

> I am very confused about unicode. Can someone point me in the right
> direction?

Try Python 3.1. This should accept Unicode strings directly for sp.call,
so you wouldn't need to encode first.

Regards,
Martin


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Sun Jul 26 00:56:59 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Sun, 26 Jul 2009 00:56:59 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
Message-ID: <h4gnmr$8cl$1@news.eternal-september.org>

On 2009-07-25 00:55:26 -0400, Carl Banks <pavlovevidence at gmail.com> said:

> But please don't put it on the same level as PHP.  Their situations
> have almost nothing in common.

Their situations have much in common; Python attracted programmers away 
from (for example) C++, becuse python is easier to master; Then php 
came along and attracted programmers away from (for example) python, 
because php is easier to master.

This doesn't mean they're on the same level - in fact, if you read 
carefully you'll see my original post said as much: python attracted 
average programmers; php attracted mediocre programmers and even some 
non-programmers, which means that php is clearly a lesser language than 
python.
-- 
Raffael Cavallaro



From nagle at animats.com  Sun Jul 26 01:47:37 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 25 Jul 2009 22:47:37 -0700
Subject: MySQLdb for Python 3.1 getting close?
In-Reply-To: <4a67e912$0$1603$742ec2ed@news.sonic.net>
References: <4a67e912$0$1603$742ec2ed@news.sonic.net>
Message-ID: <4a6bed48$0$1648$742ec2ed@news.sonic.net>

(This is actually a repost; outgoing netnews server was down for a while.)
John Nagle wrote:
>   Is MySQLdb available for Python 3.1 yet?
> 
>   http://sourceforge.net/projects/mysql-python/
> 
> says the last supported Python version is 2.5.  Any progress in sight?
> 
>                 John Nagle   


From nagle at animats.com  Sun Jul 26 01:52:18 2009
From: nagle at animats.com (John Nagle)
Date: Sat, 25 Jul 2009 22:52:18 -0700
Subject: non-owning references?
In-Reply-To: <h4capd$sn3$01$1@news.t-online.com>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<h4capd$sn3$01$1@news.t-online.com>
Message-ID: <4a6bee61$0$1648$742ec2ed@news.sonic.net>

Peter Otten wrote:
> Utpal Sarkar wrote:
> 
>> Is there a way I can tell a variable that the object it is pointing
>> too is not owned by it, in the sense that if it is the only reference
>> to the object it can be garbage collected?
> 
> http://docs.python.org/library/weakref.html

    Yes.  Weak references can be quite useful.  I have a version of
BeautifulSoup in which all the "upward" and "backwards" links are
weak references, but the "downward" and "forwards" links are strong
references.  This breaks the loops in the data structure, and thus
trees and subtrees will go away when no longer required, without
requiring a GC cycle.

				John Nagle


From israel.unterman at gmail.com  Sun Jul 26 01:52:36 2009
From: israel.unterman at gmail.com (is un)
Date: Sat, 25 Jul 2009 22:52:36 -0700 (PDT)
Subject: multiprocessing and __main__
Message-ID: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>

Hi,

Trying the multiprocessing module for the first time, I spent quite a
bit on making this code run:

from multiprocessing import Process
import time

def my_process():
    i = 0
    while 1:
        print i
        i += 1
        time.sleep(0.5)


p = Process(target=my_process, args=())
p.start()

print 'Process started'

The result was not what I expected, it seems like the process restarts
all the time, and the message 'Process started' keeps getting
printed...

Going back to the documentation, I realized that the doc was really
serious about the line:
if __name__ == '__main__' .. which I always ignore, and by changing
the code to

if __name__ == '__main__':
    p = Process(target=my_process, args=())
    p.start()

    print 'Process started'

the problem was solved.
So my question is what actually happens when I call p.start()? Is the
entry file reloaded under a different module name?

Thanks
iu2


From israel.unterman at gmail.com  Sun Jul 26 01:55:24 2009
From: israel.unterman at gmail.com (is un)
Date: Sat, 25 Jul 2009 22:55:24 -0700 (PDT)
Subject: multiprocessing and __main__
References: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>
Message-ID: <88e64585-e719-4a1a-ade9-7d54b3884503@r2g2000yqm.googlegroups.com>

Me again, fix a type in my question:
 So my question is what actually happens when I call p.start()? Is the
 *entire* file reloaded under a different module name?
>
> Thanks
> iu2



From bhardwajjayesh7 at gmail.com  Sun Jul 26 02:23:11 2009
From: bhardwajjayesh7 at gmail.com (golu)
Date: Sat, 25 Jul 2009 23:23:11 -0700 (PDT)
Subject: code debugging
Message-ID: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>

here is a code which crawls links sent to it. theres some problem with
the retrieve_url function ,plz help me out in debugging the fuction
retrive_url. This function retrives pages and saves them in file
#TODO:Visited dict grows in size it needs to be handled smartly
#Moreover server program needs to be in sync with the client eg.
Myrobot
#Take care of tag - 'if modified since',repeated links,hash links
#This is the client side of the distributed crawling framework
#It gets the list of urls to be crawled
#Then crawls the urls and stores the pages in a temporary archive
#which is then transferred to the server or grey_matter
import httplib
import os
import sys
import urlparse
import urllib2
import urllib
import zipfile
import threading

from socket import *
PAGE_DIR="C:/users/jayesh/
pages/"                                          # directory where the
web pages are stored temporarily
 
# before transfer to the grey_matter
visited=
{}                                                                 # a
dict to remember visited urls
ROBOT_COUNT=4


def fget():
    """ This function retrieves the zipped file
     containing the list of urls from the grey_matter and
     saves them in a local file 'list.txt'. """

    httplib.HTTPConnection.debuglevel=1
    request=urllib2.Request('http://192.168.153.57/list.zip')
#Requesting the zipped file
    request.add_header('Accept-encoding','gzip')           #containing
the list of urls
    opener=urllib2.build_opener()
    flag=1
    s='Waiting for server'
    while flag==1:
     try:
      op=opener.open(request)
      flag=0
     except:
         s=s+'*'
         print s
    f=open('list.zip',"wb")
    f.write(op.read())
    f.close()
    z=zipfile.ZipFile('list.zip')
    p=z.namelist()
    g=open('list.txt',"wb")
    g.write(z.read(p[0]))
    g.close()
    print 'got zipped file'

def compress():
    """ This function compresses the crawled pages and stores them in
        a single compressed file ready to be sent to the
grey_matter."""

    zfile=zipfile.ZipFile('C:/xampp/htdocs/pages.zip',mode='w')
    for fil in os.listdir(PAGE_DIR):
        full=os.path.join(PAGE_DIR,fil)
        zfile.write(full,fil)
        os.remove(full)
    os.rmdir(PAGE_DIR)             #Removing the directory after
transfer to grey_matter


x=0
class robot(threading.Thread):
    """ The main robot class which does the crawling of listed
    urls it recieves from the grey matter. It uses 3 threads which
    crawl the listed urls synchronously."""

    def __init__(self,urllist,urllistlock,dblock):
        threading.Thread.__init__(self)
        self.urllist=urllist
        self.urllistlock=urllistlock
        self.dblock=dblock

    def popurl(self):
        """ This method pops out urls from the urls file one by one
        and sends them for retrieval."""

        self.urllistlock.acquire(1)
        if(len(self.urllist)<1):
            Nexturl=None
        else:
            Nexturl=self.urllist[0]
            if Nexturl[-1]=='\n':Nexturl=Nexturl[:-1]
            del self.urllist[0]
        self.urllistlock.release()
        return Nexturl

    def retrieve_url(self,url):
        """ The main method of the robot class and is called
        run method to retrieve the given urls from the web."""
        global x
        if url is not None:

         try:
            if visited.has_key(url): return
            pieces=urlparse.urlparse(url)
            filepath=pieces[2]
            if filepath != '':
             filepath=filepath[1:]
             filename=filepath.split("/")[-1]
            else:
              filename=x+'.htm'
              x+=1

            path=os.path.join(PAGE_DIR,filename)
            url=urlparse.urlunparse(pieces)
            p=url.rfind('#')                   #temporary
            if p!=-1:
                url=url[:p]

            visited[url]=1
            m=urllib2.urlopen(url)

            fopen=open(path,'wb')

            fopen.seek(0)
            fopen.write(url+'|')

            fopen.write(m.read())
            fopen.close()
            print url ,'retrieved'

         except IOError:
            print url
            print "ERROR:OOPS! THE URL CAN'T BE RETRIEVED"

        return

    def run(self):
        while(1):
            url=self.popurl()
            if url is None:
                break
            try:
             self.retrieve_url(url)
            except:sys.exit()

if __name__=='__main__':

  s=socket(AF_INET,SOCK_STREAM)
  s.bind(('',444))
  s.listen(5)
  q,v=s.accept()
  count=1
  print 'Connecting...'
  while 1:
    print 'Phase: %s' %(count)
    message=q.recv(3)

    if(message!='yes'):continue
    print 'Connected'
    count=count+1
    fget()             # Calling the fget method to get the url list
from
                       # grey_matter(server).
    try:
     os.mkdir(PAGE_DIR)
    except: print 'Cant make dir'
    try:
     f=open('list.txt','r')
     urllist=f.readlines()
     f.close()
    except:
        print 'Error opening urls file'
        sys.exit()
    print 'startting threads'
    urllistlock=threading.Lock()
    dblock=threading.Lock()
    botlist=[]
    for X in range(0,ROBOT_COUNT):
         newbot=robot(urllist,urllistlock,dblock)
         newbot.setName('X')
         botlist.append(newbot)
         newbot.start()

    for X in range(0,ROBOT_COUNT):
         botlist[X].join()

    compress()
    try:
     q.send('yes')
    except:
        print 'socket disconnected'
        print sys.exit()




From clp2 at rebertia.com  Sun Jul 26 02:28:48 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sat, 25 Jul 2009 23:28:48 -0700
Subject: code debugging
In-Reply-To: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
References: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
Message-ID: <50697b2c0907252328t70ecd0ddp20898ddf497b5190@mail.gmail.com>

On Sat, Jul 25, 2009 at 11:23 PM, golu<bhardwajjayesh7 at gmail.com> wrote:
> here is a code which crawls links sent to it. theres some problem with
> the retrieve_url function ,plz help me out in debugging the fuction
> retrive_url. This function retrives pages and saves them in file

Please specify exactly what the problem is that you are experiencing.
If you are getting an error, please provide the error message and full
traceback.

Cheers,
Chris
-- 
http://blog.rebertia.com


From bhardwajjayesh7 at gmail.com  Sun Jul 26 02:33:27 2009
From: bhardwajjayesh7 at gmail.com (golu)
Date: Sat, 25 Jul 2009 23:33:27 -0700 (PDT)
Subject: code debugging
References: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
	<mailman.3727.1248589730.8015.python-list@python.org>
Message-ID: <c7dd7062-fcf8-49e9-aae0-cd3c88f6b204@d4g2000prc.googlegroups.com>

On Jul 26, 11:28?am, Chris Rebert <c... at rebertia.com> wrote:
> On Sat, Jul 25, 2009 at 11:23 PM, golu<bhardwajjaye... at gmail.com> wrote:
> > here is a code which crawls links sent to it. theres some problem with
> > the retrieve_url function ,plz help me out in debugging the fuction
> > retrive_url. This function retrives pages and saves them in file
>
> Please specify exactly what the problem is that you are experiencing.
> If you are getting an error, please provide the error message and full
> traceback.
>
> Cheers,
> Chris
> --http://blog.rebertia.com

i want to save pages in a directory and i m using the urls to get
filenames. The program gets stuck in the saving step.can u suggest me
a way to save a page e.g google.com as a file google.html


From bhardwajjayesh7 at gmail.com  Sun Jul 26 02:57:35 2009
From: bhardwajjayesh7 at gmail.com (golu)
Date: Sat, 25 Jul 2009 23:57:35 -0700 (PDT)
Subject: web page retrieve problems
Message-ID: <16343e3d-1be4-422b-8bff-c07fa4aa4c54@j9g2000prh.googlegroups.com>

the following function retrieves pages from the web and saves them in
a specified dir. i want to extract the respective filenames from the
urls e.g the page code.google.com shud be saved as code-google.htm  or
something similar. can u suggest me a way to do it
def retrieve_url(self,url):
        """ The main method of the robot class and is called
        run method to retrieve the given urls from the web."""

        if url is not None:

         try:
            if visited.has_key(url): return
            pieces=urlparse.urlparse(url)
            filepath=pieces[2]
            if filepath != '':
             filepath=filepath[1:]
             filename=filepath.split("/")[-1]
            else:
              filename='home.htm'


            path=os.path.join(PAGE_DIR,filename)
            url=urlparse.urlunparse(pieces)
            p=url.rfind('#')                   #temporary
            if p!=-1:
                url=url[:p]

            visited[url]=1
            m=urllib2.urlopen(url)

            fopen=open(path,'wb')

            fopen.seek(0)
            fopen.write(url+'|')

            fopen.write(m.read())
            fopen.close()
            print url ,'retrieved'

         except IOError:
            print url
            print "ERROR:OOPS! THE URL CAN'T BE RETRIEVED"

        return


From emmanuel.surleau at gmail.com  Sun Jul 26 03:42:33 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Sun, 26 Jul 2009 09:42:33 +0200
Subject: len() should always return something
In-Reply-To: <h4g1ok$2tj2$1@adenine.netfront.net>
References: <24639361.post@talk.nabble.com> <m2eis4etyb.fsf@cs.uu.nl>
	<h4g1ok$2tj2$1@adenine.netfront.net>
Message-ID: <200907260942.33841.emmanuel.surleau@gmail.com>

On Sunday 26 July 2009 00:42:26 Marcus Wanner wrote:
> On 7/25/2009 10:08 AM, Piet van Oostrum wrote:
> >>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:
> >>
> >> SD> Ambiguity essentially boils down to being unable to reasonably
> >> predict SD> the expectation of the coder. I say "reasonably", because if
> >> you allow SD> unreasonable situations, everything is "ambiguous":
> >
> > That's for me the reason that len(42) is ambiguous. The OP apparently
> > had 1 as expectation, whereas my first thought was the minimal number of
> > bits to represent the number and 7.5 million came later :=). The number
> > of bits I certainly find reasonable, and I would find the number of
> > decimal digits equally reasonable. More so than 1, actually. 1 as the
> > length of an int doesn't give any information.
>
> Well, for my two cents, I will say that the number of binary bits or
> decimal digits is certainly the most sensible return value, and that the
> former is the most useful, because the latter can be got with
> len(str(42)). However, the former can also be (/slightly/ less)easily
> got with len(bin(42))-2...


For my two eurocents, I'd expect such an operator to be called "sizeof" and 
when applied to a collection, to also return the number of bits it uses. I 
don't think a 'len' function has meaning when applied to something else than a 
collection, really...

> I also think that "Explicit is better than implicit." says that there
> should be no return value in this case, as any return value would be
> implicit.

Agreed.

Cheers,

Emm


From hendrik at microcorp.co.za  Sun Jul 26 03:48:49 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Sun, 26 Jul 2009 09:48:49 +0200
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
Message-ID: <200907260948.49293.hendrik@microcorp.co.za>

On Saturday 25 July 2009 20:30:54 Michal Kwiatkowski wrote:
> Hi,
>
> Is there a way to tell if a generator has been exhausted using pure
> Python code? I've looked at CPython sources and it seems that
> something like "active"/"exhausted" attribute on genobject is missing
> from the API. For the time being I am using a simple C extension to
> look at f_stacktop pointer of the generator frame, which seems to
> differentiate active generators from exhausted ones. See
> http://bazaar.launchpad.net/~ruby/pythoscope/support-python2.3/annotate/286
>/pythoscope/_util.c#L16 for complete source code.
>
> I may be missing something obvious here. Is there a better way to tell
> if a given generator object is still active or not?

Is there a reason why you cannot just call the next method and handle
the StopIteration when it happens?

- Hendrik


From emmanuel.surleau at gmail.com  Sun Jul 26 03:50:42 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Sun, 26 Jul 2009 09:50:42 +0200
Subject: non-owning references?
In-Reply-To: <8763di5d1d.fsf@benfinney.id.au>
References: <eaa61b3a-5c1d-452d-ab2e-648037d452dc@i6g2000yqj.googlegroups.com>
	<87fxcm5gny.fsf@busola.homelinux.net>
	<8763di5d1d.fsf@benfinney.id.au>
Message-ID: <200907260950.42765.emmanuel.surleau@gmail.com>

On Friday 24 July 2009 17:14:06 you wrote:
> Hrvoje Niksic <hniksic at xemacs.org> writes:
> > The term "variable" is used in the Python language reference and
> > elsewhere
>
> Yes. It should also be abundantly clear from the constant stream of
> confused newbies on this point that its usage of that term is different
> to what many expect from usage elsewhere.
>
> > and is quite compatible with how other popular languages (Java, PHP,
> > Lisp, ...) use it. Please stop complaining about valid terminology; it
> > is not helpful.
>
> I disagree with your assertions.
>
> Rather than yet another round of this tedious debate, I merely point
> interested readers to <URL:http://effbot.org/zone/python-objects.htm>
> and ask them to draw their own conclusion on how compatible their
> pre-existing ?variable? concept is with Python's object reference
> model.

Then I must be one of these "confused newbies". After a cursory look at your 
article, I don't see a difference with Java variables (as long as we speak 
about non-primitive types).

Cheers,

Emm


From martin at v.loewis.de  Sun Jul 26 04:04:12 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 10:04:12 +0200
Subject: C-API, tp_dictoffset vs tp_members
In-Reply-To: <7cl194F28ojoqU1@mid.uni-berlin.de>
References: <7cl194F28ojoqU1@mid.uni-berlin.de>
Message-ID: <4A6C0DFC.4030702@v.loewis.de>

> When would I use PyObject_SetAttrString/tp_dictoffset instead of tp_members? 

When I have a variable list of attributes, and cannot statically know
what those attributes might be.

> I have a predefined set of members, some of which are optional.

Having optional fields is also a good reason.

> The problem 
> I had with an embedded dictionary was that I can't see its elements using 
> "dir()".

How so? That should work fine.

> Now I just converted to using tp_members, and it still seems to 
> work correctly for the cases I tested.

So how do you do optional fields now? In particular, how would you do
optional integers?

> Even better, I can declare the fields 
> as read-only then and add doc-strings. So, I wonder, what made the original 
> author[2] use tp_dictoffset instead? 

Most likely, it was the simplest approach. This code only wants to set
the attributes, and never read them. It's easier to maintain: if you
want to add a field with tp_members, you have to change multiple places,
and you have to consider garbage collection (assuming you have embedded
objects). With tp_dictoffset, adding another attribute is easy.

Regards,
Martin


From jessica.1980.smith at gmail.com  Sun Jul 26 04:12:47 2009
From: jessica.1980.smith at gmail.com (Jessica R Smith)
Date: Sun, 26 Jul 2009 01:12:47 -0700 (PDT)
Subject: I am trying to compile python 2.6.2 on my Mac
Message-ID: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>

Hello,
I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7

I downloaded python 2.6.2 from here:
  - http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2

I unpacked it.

I ran these shell commands:
  - ./configure --prefix=/pt/p
  - make

Near the end of the make output I see this message:

. Failed to find the necessary bits to build these modules:
. _bsddb             gdbm               linuxaudiodev
. ossaudiodev        readline           spwd
. sunaudiodev
. To find the necessary bits, look in setup.py in detect_modules() for
the module's name.

I looked in setup.py in detect_modules()

It is not clear to me how to proceed.

I think that I want the module: "readline"

I doubt I need the other modules like linuxaudiodev, etc.

If you have any clues or opinions on how I can build the module
"readline",
please feel free to share.

Thanks,
JRS


From nobody at nowhere.com  Sun Jul 26 04:13:30 2009
From: nobody at nowhere.com (Nobody)
Date: Sun, 26 Jul 2009 09:13:30 +0100
Subject: Failed Regression Test: What socket.gethostname() is supposed
	to	return?
References: <mailman.3722.1248561042.8015.python-list@python.org>
Message-ID: <pan.2009.07.26.08.13.29.766000@nowhere.com>

On Sun, 26 Jul 2009 08:30:30 +1000, Lie Ryan wrote:

> since on my system socket.gethostname() returns 'lieryan', and since
> socket.gethostbyname('lieryan') does not resolve to anything; the test
> becomes an error.
> 
> My system is Gentoo, but I think this also happened on Ubuntu (still on
> this laptop). The trunk failed in similar manner.
> 
> Do I have a misconfigured system or is the test faulty?

Misconfigured system.

> I tracked the code for socket.gethostname() and socket.gethostbyname()
> and found that they are simply a wrapper for gethostname() from #import
> <unistd.h> (http://linux.die.net/man/2/gethostname) and gethostbyname()
> from #import <netdb.h> (http://linux.die.net/man/3/gethostbyname). A
> simple test in C found that the C's equivalent to
> gethostbyname(gethostname()) returns a null pointer (used to indicate
> error, per documentation).
> 
> So, the question is: what is socket.gethostname() is supposed to return
> that will be a valid argument for socket.gethostbyname()?

gethostname() returns the hostname.

gethostbyname() returns some information about the host (specifically,
aliases and IP addresses) obtained by platform-specific means (which
normally includes /etc/hosts and DNS, and may also include NIS, LDAP, and
others; see the nsswitch.conf manpage for more details).

Python's socket.gethostname() simply returns the first IP address;
socket.gethostbyname_ex() returns all of the information which libc's
gethostbyname() provides.

In order for gethostbyname() to work, the host must be listed in one of
the databases which it uses. The simplest way to achieve this is to add an
entry to /etc/hosts, e.g.:

	192.168.0.2 lieryan.yourdomain.com lieryan

or just:

	192.168.0.2 lieryan

> PS: I found an MSDN article by Microsoft stating that
> gethostbyname(gethostname) is guaranteed to always succeed
> (http://msdn.microsoft.com/en-us/library/ms738527(VS.85).aspx); is this
> guarantee also true in linux?

No.



From gagsl-py2 at yahoo.com.ar  Sun Jul 26 04:14:34 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 26 Jul 2009 05:14:34 -0300
Subject: multiprocessing and __main__
References: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>
Message-ID: <op.uxn06klpx6zn5v@gabriel.sleipnir-bsas>

En Sun, 26 Jul 2009 02:52:36 -0300, is un <israel.unterman at gmail.com>  
escribi?:

> Trying the multiprocessing module for the first time, I spent quite a
> bit on making this code run:
> [...]
> The result was not what I expected, it seems like the process restarts
> all the time, and the message 'Process started' keeps getting
> printed...
>
> Going back to the documentation, I realized that the doc was really
> serious about the line:
> if __name__ == '__main__' .. which I always ignore, and by changing
> the code to
>
> if __name__ == '__main__':
>     p = Process(target=my_process, args=())
>     p.start()
>
>     print 'Process started'
>
> the problem was solved.
> So my question is what actually happens when I call p.start()? Is the
> entry file reloaded under a different module name?

The multiprocessing module handles multiple (separate) processes. On  
Windows, a new Python interpreter is launched; on other OSs a different  
approach is used. In any case, you get distinct and separate processes,  
each one with its own set of loaded modules, etc.

-- 
Gabriel Genellina



From clp2 at rebertia.com  Sun Jul 26 04:37:43 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 26 Jul 2009 01:37:43 -0700
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
Message-ID: <50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>

On Sun, Jul 26, 2009 at 1:12 AM, Jessica R
Smith<jessica.1980.smith at gmail.com> wrote:
> Hello,
> I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7
>
> I downloaded python 2.6.2 from here:
> ?- http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2
>
> I unpacked it.
>
> I ran these shell commands:
> ?- ./configure --prefix=/pt/p
> ?- make
>
> Near the end of the make output I see this message:
>
> . Failed to find the necessary bits to build these modules:
> . _bsddb ? ? ? ? ? ? gdbm ? ? ? ? ? ? ? linuxaudiodev
> . ossaudiodev ? ? ? ?readline ? ? ? ? ? spwd
> . sunaudiodev
> . To find the necessary bits, look in setup.py in detect_modules() for
> the module's name.
>
> I looked in setup.py in detect_modules()
>
> It is not clear to me how to proceed.
>
> I think that I want the module: "readline"
>
> I doubt I need the other modules like linuxaudiodev, etc.
>
> If you have any clues or opinions on how I can build the module
> "readline",
> please feel free to share.

You need to install the GNU Readline library
(http://tiswww.case.edu/php/chet/readline/rltop.html), which the
module depends on.

You might consider installing Python through MacPorts or Fink instead,
as they automate the compilation and installation process and take
care of dependencies (such as GNU Readline) for you:
http://www.macports.org/
http://www.finkproject.org/

Cheers,
Chris
-- 
http://blog.rebertia.com


From constant.beta at gmail.com  Sun Jul 26 04:45:21 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Sun, 26 Jul 2009 01:45:21 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
Message-ID: <2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>

On Jul 26, 1:10?am, Ben Finney <ben+pyt... at benfinney.id.au> wrote:
> Michal Kwiatkowski <constant.b... at gmail.com> writes:
> > I may be missing something obvious here. Is there a better way to tell
> > if a given generator object is still active or not?
>
> ? ? foo = the_generator_object
> ? ? try:
> ? ? ? ? do_interesting_thing_that_needs(foo.next())
> ? ? except StopIteration:
> ? ? ? ? generator_is_exhausted()
>
> In other words, don't LBYL, because it's EAFP. Whatever you need to do
> that requires the next item from the generator, do that; you'll get a
> specific exception if the generator is exhausted.

The thing is I don't need the next item. I need to know if the
generator has stopped without invoking it. Why - you may ask. Well,
the answer needs some explaining.

I'm working on the Pythoscope project (http://pythoscope.org) and I
use tracing mechanisms of CPython (sys.settrace) to capture function
calls and values passed to and from them. Now, the problem with
generators is that when they are ending (i.e. returning instead of
yielding) they return a None, which is in fact indistinguishable from
"yield None". That means I can't tell if the last captured None was in
fact yielded or is a bogus value which should be rejected. Let me show
you on an example.

import sys

def trace(frame, event, arg):
    if event != 'line':
        print frame, event, arg
    return trace

def gen1():
    yield 1
    yield None

def gen2():
    yield 1

sys.settrace(trace)
print "gen1"
g1 = gen1()
g1.next()
g1.next()
print "gen2"
g2 = gen2()
[x for x in g2]
sys.settrace(None)

The first generator isn't finished, it yielded 1 and None. Second one
is exhausted after yielding a single value (1). The problem is that,
under Python 2.4 or 2.3 both invocations will generate the same trace
output. So, to know whether the last None was actually a yielded value
I need to know if a generator is active or not.

Your solution, while gives me an answer, is not acceptable because
generators can cause side effects (imagine call to launch_rockets()
before the next yield statement ;).

Cheers,
mk


From jessica.1980.smith at gmail.com  Sun Jul 26 05:01:31 2009
From: jessica.1980.smith at gmail.com (Jessica Smith)
Date: Sun, 26 Jul 2009 02:01:31 -0700
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
	<50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
Message-ID: <ac1384480907260201l53d49d44h33e2e884d3bf31e8@mail.gmail.com>

Chris thanks!!

other members:

I read this:
  - http://chrismiles.livejournal.com/25648.html

I did this:
  - install mac ports
  - port install readline
  - vi  setup.py

    def detect_modules(self):
        # Ensure that /usr/local is always used
        add_dir_to_list(self.compiler.library_dirs, '/opt/local/lib')
        add_dir_to_list(self.compiler.include_dirs, '/opt/local/include')

  - configure --prefix=/pt/p
  - make
  - make install

I'm happy now!

JRS


On 7/26/09, Chris Rebert <clp2 at rebertia.com> wrote:
> On Sun, Jul 26, 2009 at 1:12 AM, Jessica R
> Smith<jessica.1980.smith at gmail.com> wrote:
>> Hello,
>> I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7
>>
>> I downloaded python 2.6.2 from here:
>> ?- http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2
>>
>> I unpacked it.
>>
>> I ran these shell commands:
>> ?- ./configure --prefix=/pt/p
>> ?- make
>>
>> Near the end of the make output I see this message:
>>
>> . Failed to find the necessary bits to build these modules:
>> . _bsddb ? ? ? ? ? ? gdbm ? ? ? ? ? ? ? linuxaudiodev
>> . ossaudiodev ? ? ? ?readline ? ? ? ? ? spwd
>> . sunaudiodev
>> . To find the necessary bits, look in setup.py in detect_modules() for
>> the module's name.
>>
>> I looked in setup.py in detect_modules()
>>
>> It is not clear to me how to proceed.
>>
>> I think that I want the module: "readline"
>>
>> I doubt I need the other modules like linuxaudiodev, etc.
>>
>> If you have any clues or opinions on how I can build the module
>> "readline",
>> please feel free to share.
>
> You need to install the GNU Readline library
> (http://tiswww.case.edu/php/chet/readline/rltop.html), which the
> module depends on.
>
> You might consider installing Python through MacPorts or Fink instead,
> as they automate the compilation and installation process and take
> care of dependencies (such as GNU Readline) for you:
> http://www.macports.org/
> http://www.finkproject.org/
>
> Cheers,
> Chris
> --
> http://blog.rebertia.com
>


From __peter__ at web.de  Sun Jul 26 05:08:10 2009
From: __peter__ at web.de (Peter Otten)
Date: Sun, 26 Jul 2009 11:08:10 +0200
Subject: strange error when trying to log something
References: <0aef181f-b002-432d-b046-dbbbd713d1dd@d32g2000yqh.googlegroups.com>
	<h49ah5$hv3$02$1@news.t-online.com> <h4fau1$gvn$1@panix3.panix.com>
Message-ID: <h4h6d7$bbu$00$1@news.t-online.com>

Aahz wrote:

> In article <h49ah5$hv3$02$1 at news.t-online.com>,
> Peter Otten  <__peter__ at web.de> wrote:
>>
>>I have a hunch that you are triggering a reload() somewhere. Example:
>>
>>Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18)
>>[GCC 4.3.3] on linux2
>>Type "help", "copyright", "credits" or "license" for more information.
>>>>> import weakref
>>>>> weakref.WeakValueDictionary()
>><WeakValueDictionary at 140598938447312>
>>>>> import UserDict
>>>>> reload(UserDict)
>><module 'UserDict' from '/usr/lib/python2.6/UserDict.pyc'>
>>>>> weakref.WeakValueDictionary()
>>Traceback (most recent call last):
>>  File "<stdin>", line 1, in <module>
>>  File "/usr/lib/python2.6/weakref.py", line 51, in __init__
>>    UserDict.UserDict.__init__(self, *args, **kw)
>>TypeError: unbound method __init__() must be called with UserDict instance
>>as first argument (got WeakValueDictionary instance instead)
> 
> Nice sleuthing!  How did you figure that out?

Roughly: 

- The poster's description/remedy makes no sense (to me); have a look at the 
traceback.
- Nothing suspicious except the actual error message. Isn't 
WeakValueDictionary a UserDict? Verify.
- There must be two different UserDict classes. This can happen to an 
unsuspecting user by importing the main script or by doing a reload().
UserDict is unlikely to be the main script, and web frameworks (django was 
mentioned) often use a reload mechanism to avoid frequent server restarts.
- Reproduce the error.

Peter



From gagsl-py2 at yahoo.com.ar  Sun Jul 26 05:19:52 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 26 Jul 2009 06:19:52 -0300
Subject: code debugging
References: <a7b323ec-e24d-4abd-9aa3-f6f7c4c71ca9@x5g2000prf.googlegroups.com>
	<mailman.3727.1248589730.8015.python-list@python.org>
	<c7dd7062-fcf8-49e9-aae0-cd3c88f6b204@d4g2000prc.googlegroups.com>
Message-ID: <op.uxn37exfx6zn5v@gabriel.sleipnir-bsas>

En Sun, 26 Jul 2009 03:33:27 -0300, golu <bhardwajjayesh7 at gmail.com>  
escribi?:

> i want to save pages in a directory and i m using the urls to get
> filenames. The program gets stuck in the saving step.can u suggest me
> a way to save a page e.g google.com as a file google.html

You may use str.translate to replace/remove all undesired characters:

py> import string
py> valid = string.ascii_letters+string.digits+'.'
py> invalid = ''.join(chr(x) for x in range(256) if chr(x) not in valid)
py> table = string.maketrans(invalid, '_'*len(invalid))
py> x = 'http://docs.python.org/library/string.html'
py> x.translate(table)
'http___docs.python.org_library_string.html'

See http://docs.python.org/library/stdtypes.html#str.translate

-- 
Gabriel Genellina



From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 05:45:03 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 09:45:03 GMT
Subject: len() should always return something
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>
	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
Message-ID: <027c168c$0$5185$c3e8da3@news.astraweb.com>

On Sat, 25 Jul 2009 16:21:39 -0700, Erik Max Francis wrote:

> Steven D'Aprano wrote:
>> But it's not "practically every function". It's hardly any function at
>> all -- in my code, I don't think I've ever wanted this behavior. I
>> would consider it an error for function(42) and function([42]) to
>> behave the same way. One is a scalar, and the other is a vector --
>> they're different things, it's poor programming practice to treat them
>> identically.
>> 
>> (If Matlab does this, so much the worse for Matlab, in my opinion.)
> 
> There's actually good reason to do this in heavily matrix-oriented
> specialized languages; there are numerous applications where scalars and
> 1x1 matrices are mathematically equivalent.


I'm curious what those applications are, because regular multiplication 
behaves differently depending on whether you have a 1x1 matrix or a 
scalar:

[[2]]*[[1, 2, 3], [2, 3, 4]] is not defined

2*[[1, 2, 3], [2, 3, 4]] = [[2, 4, 6], [2, 6, 8]]


I'm curious as to what these applications are, and what they're actually 
doing. Kronecker multiplication perhaps? Do you have some examples of 
those applications?



-- 
Steven


From doomster at knuut.de  Sun Jul 26 05:45:37 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Sun, 26 Jul 2009 11:45:37 +0200
Subject: C-API, tp_dictoffset vs tp_members
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
Message-ID: <7d2mu7F27a9tbU1@mid.uni-berlin.de>

"Martin v. L?wis" wrote:
>> I have a predefined set of members, some of which are optional.
> 
> Having optional fields is also a good reason.

What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then? I would
 have though that the former describes an optional field, because the
 behaviour of accessing it when it is NULL is the same as accessing a
 nonexistent field. However, I see that it still appears in the dir()
 output even if it is NULL, so it seems I'm misunderstanding this.

>> The problem
>> I had with an embedded dictionary was that I can't see its elements using
>> "dir()".
> 
> How so? That should work fine.

>>> import example
>>> x = example.Example()
>>> dir(x)
['__class__', '__delattr__', '__doc__', '__getattribute__',
'__hash__', '__init__', '__new__', '__reduce__', '__reduce_ex__',
'__repr__', '__setattr__', '__str__']
>>> x.example_attribute
'example value'

The 'example_attribute' can be accessed, but it is not visible in the
dir() output. The code for this is below.


>> Now I just converted to using tp_members, and it still seems to
>> work correctly for the cases I tested.
> 
> So how do you do optional fields now? In particular, how would you do
> optional integers?

See above, I would expect T_OBJECT_EX to do that.

Thanks!

Uli



/* example.c

 gcc -Wall example.c -shared -I /usr/include/python2.5 -o example.so
*/

#include <Python.h>
#include <structmember.h>

typedef struct {
    PyObject_HEAD
    PyObject* dict;
} Example;

static void
Example_dealloc(PyObject* self)
{
    Example* ex = (Example*)self;
    Py_XDECREF(ex->dict);
    self->ob_type->tp_free(self);
}

static PyObject *
Example_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
    Example* self;
    PyObject* attr;

    self = (Example*)type->tp_alloc(type, 0);
    if(self==NULL)
        return NULL;

    self->dict = PyDict_New();
    if(self->dict==NULL) {
        Py_DECREF(self);
        return NULL;
    }

    attr = PyString_FromString("example value");
    if(PyObject_SetAttrString((PyObject*)self, "example_attribute", attr)<0) {
        Py_DECREF(self);
        return NULL;
    }

    return (PyObject*)self;
}

static PyTypeObject ExampleType = {
    PyObject_HEAD_INIT(NULL)
    0,                         /*ob_size*/
    "example.Example",         /*tp_name*/
    sizeof(Example),           /*tp_basicsize*/
    0,                         /*tp_itemsize*/
    Example_dealloc,           /*tp_dealloc*/
    0,                         /*tp_print*/
    0,                         /*tp_getattr*/
    0,                         /*tp_setattr*/
    0,                         /*tp_compare*/
    0,                         /*tp_repr*/
    0,                         /*tp_as_number*/
    0,                         /*tp_as_sequence*/
    0,                         /*tp_as_mapping*/
    0,                         /*tp_hash */
    0,                         /*tp_call*/
    0,                         /*tp_str*/
    0,                         /*tp_getattro*/
    0,                         /*tp_setattro*/
    0,                         /*tp_as_buffer*/
    Py_TPFLAGS_DEFAULT,        /*tp_flags*/
    0,                         /* tp_doc */
    0,                         /* tp_traverse */
    0,                         /* tp_clear */
    0,                         /* tp_richcompare */
    0,                         /* tp_weaklistoffset */
    0,                         /* tp_iter */
    0,                         /* tp_iternext */
    0,                         /* tp_methods */
    0,                         /* tp_members */
    0,                         /* tp_getset */
    0,                         /* tp_base */
    0,                         /* tp_dict */
    0,                         /* tp_descr_get */
    0,                         /* tp_descr_set */
    offsetof(Example, dict),   /* tp_dictoffset */
    0,                         /* tp_init */
    0,                         /* tp_alloc */
    Example_new,               /* tp_new */
};

void
initexample(void) 
{
    PyObject* m;

    if (PyType_Ready(&ExampleType) < 0)
        return;

    m = Py_InitModule3("example", 0,
                       "Example module that creates an extension type.");

    if (m == NULL)
      return;

    Py_INCREF(&ExampleType);
    PyModule_AddObject(m, "Example", (PyObject*)&ExampleType);
}



From israelu at elbit.co.il  Sun Jul 26 05:50:15 2009
From: israelu at elbit.co.il (iu2)
Date: Sun, 26 Jul 2009 02:50:15 -0700 (PDT)
Subject: multiprocessing and __main__
References: <baf19d7a-fae3-426a-abd5-707962ac9fa9@26g2000yqk.googlegroups.com>
Message-ID: <fa60d2c6-1016-4c1a-8a6c-00e3e5fa8e23@r2g2000yqm.googlegroups.com>

On Jul 26, 8:52?am, is un <israel.unter... at gmail.com> wrote:
> Hi,
>
> Trying the multiprocessing module for the first time, I spent quite a
> bit on making this code run:
>
> from multiprocessing import Process
> import time
>
> def my_process():
> ? ? i = 0
> ? ? while 1:
> ? ? ? ? print i
> ? ? ? ? i += 1
> ? ? ? ? time.sleep(0.5)
>
> p = Process(target=my_process, args=())
> p.start()
>
> print 'Process started'
>
> The result was not what I expected, it seems like the process restarts
> all the time, and the message 'Process started' keeps getting
> printed...
>
> Going back to the documentation, I realized that the doc was really
> serious about the line:
> if __name__ == '__main__' .. which I always ignore, and by changing
> the code to
>
> if __name__ == '__main__':
> ? ? p = Process(target=my_process, args=())
> ? ? p.start()
>
> ? ? print 'Process started'
>
> the problem was solved.
> So my question is what actually happens when I call p.start()? Is the
> entry file reloaded under a different module name?
>
> Thanks
> iu2

Ok, I found it, it is nicely documented, I missed it before. Case
closed.


From doomster at knuut.de  Sun Jul 26 05:54:55 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Sun, 26 Jul 2009 11:54:55 +0200
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org>
Message-ID: <7d2nfnF29tk6fU1@mid.uni-berlin.de>

Tom wrote:
> s = sauce.replace("\n", "")
> 
> Sauce is a string, read from a file, that I need to remove newlines
> from. This code works fine in Linux, but not in Windows. rstrip("\n")
> won't work for me, so anybody know how to get this working on Windows?

I'm pretty sure this works regardless of the system. What might change is 
the way that a line is terminated: MS Windows by default uses a CR/LF 
('\r\n') pair, while most other systems just an LF ('\n').

I'd adapt the code to accept either line ending on either system.

If that's not what you want, you should improve your "doesn't work" 
description. ;)

Uli




From max at alcyone.com  Sun Jul 26 06:11:02 2009
From: max at alcyone.com (Erik Max Francis)
Date: Sun, 26 Jul 2009 03:11:02 -0700
Subject: len() should always return something
In-Reply-To: <027c168c$0$5185$c3e8da3@news.astraweb.com>
References: <24639361.post@talk.nabble.com>	<7ct4b8F29mednU1@mid.uni-berlin.de>	<mailman.3699.1248490256.8015.python-list@python.org>	<027a9f1a$0$5185$c3e8da3@news.astraweb.com>	<04-dnQ5L6JkeDvbXnZ2dnUVZ_sOdnZ2d@giganews.com>
	<027c168c$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <ZIOdnSQ36v4ltvHXnZ2dnUVZ_u6dnZ2d@giganews.com>

Steven D'Aprano wrote:
> I'm curious what those applications are, because regular multiplication 
> behaves differently depending on whether you have a 1x1 matrix or a 
> scalar:
> 
> [[2]]*[[1, 2, 3], [2, 3, 4]] is not defined
> 
> 2*[[1, 2, 3], [2, 3, 4]] = [[2, 4, 6], [2, 6, 8]]
> 
> I'm curious as to what these applications are, and what they're actually 
> doing. Kronecker multiplication perhaps? Do you have some examples of 
> those applications?

The most obvious example would be the matrix algebra equivalent of the 
calculation of the dot product, the equivalent of a dot product in 
normal vector algebra.  If you have two 3-vectors (say), u = (u_1, u_2, 
u_3) and v = (v_1, v_2, v_3), then the dot product is the sum of the 
pairwise products of these terms, u dot v = sum_i u_i v_i = u_1 v_1 + 
u_2 v_2 + u_3 v_3.

Nothing revolutionary there.  The matrix way of writing this wouldn't 
obviously work, since multiplying two nx1 or (1xn) matrixes by each 
other is invalid.  But you _can_ multiply a nx1 matrix by an 1xn matrix, 
and you get the equivalent of the dot product:

	u v^T = ( u dot v ),

where the right hand side of the equation is formally a 1x1 matrix 
(intended to be indicated by the parentheses), but you can see how it is 
useful to think of it as just a scalar, because it's really just a 
matrix version of the same thing as a dot product.

This stretches out to other kinds of applications, where, say, in tensor 
calculus, you can think of a contravariant vector as being transformed 
into a covariant vector by the application of the matrix tensor, which 
is written as lowering an index.  The components of the contravariant 
vector can be thought of as a column vector, while the components of a 
covariant vector can be represented with a row vector.  The application 
  of the metric tensor to a contravariant vector turns it into a row 
vector, and then contracting over the two vectors gives you the inner 
product as above.  The applications and contractions can all be 
visualized as matrix multiplications.  (Contrary to a popularization, 
tensors _aren't_ generalizations of matrices, but their components can be.)

It's a bunch of other examples like that where you end up with a 1x1 
matrix that really represents a scalar, and since that was intended 
there really isn't a lot of efficacy to treat it as a separate entity. 
Especially if you're dealing with a special-purpose language where 
everything is really a form of an generalized array representation of 
something _anyway_.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
   Scars are like memories. We do not have them removed.
    -- Chmeee


From wilk at flibuste.net  Sun Jul 26 06:22:34 2009
From: wilk at flibuste.net (William Dode)
Date: 26 Jul 2009 10:22:34 GMT
Subject: ANN: psyco V2
References: <mailman.3252.1247798900.8015.python-list@python.org>
	<639d8155-ab27-462b-9401-73448a3c9575@b15g2000yqd.googlegroups.com>
	<mailman.3613.1248368814.8015.python-list@python.org>
	<4a696af3$0$442$426a74cc@news.free.fr>
	<mailman.3687.1248467986.8015.python-list@python.org>
Message-ID: <4a6c2e6a$0$424$426a34cc@news.free.fr>

On 24-07-2009, Christian Tismer wrote:
> On 7/24/09 1:04 AM, William Dode wrote:
>> On 23-07-2009, Christian Tismer wrote:
> ...
>
>>> Wasn't the project plan saying the opposite, borrowing
>>> some ideas from psyco? :-)
>>> http://code.google.com/p/unladen-swallow/wiki/ProjectPlan
>>
>> How do you see the future of psyco when unladen-swallow will grab the
>> best of psyco (if they can !) ?
>
> I have no objections, but also no idea so far how that could work.
> Sounded like an unreflected idea to me, without seriously
> checking the possibilities and/or implications. The same
> kind of research apparently did not happen concerning PyPy,
> which IMHO is much more suitable to take advantage from.
>
> This is for the current status of psyco, of course.
> It will change dramatically in the next months, slowly
> adopting some of PyPy's ideas. Then it might start to
> make more sense.

I didn't understand how psyco could use somes PyPy's ideas, i thought 
it's only the opposite... So i was going to read the PyPy's 
documentation : it's fascinating !!!

But how to test it ? The doc says : "When PyPy is translated into an 
executable like pypy-c, the executable contains a full virtual machine 
that can optionally include a Just-In-Time compiler."

Where is this 'option', is there somethings to activate it ?

thx

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From deets at nospam.web.de  Sun Jul 26 06:51:31 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sun, 26 Jul 2009 12:51:31 +0200
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <mailman.3733.1248598894.8015.python-list@python.org>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>	<50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
	<mailman.3733.1248598894.8015.python-list@python.org>
Message-ID: <7d2qpkF29u2uiU1@mid.uni-berlin.de>

Jessica Smith schrieb:
> Chris thanks!!
> 
> other members:
> 
> I read this:
>   - http://chrismiles.livejournal.com/25648.html
> 
> I did this:
>   - install mac ports
>   - port install readline
>   - vi  setup.py
> 
>     def detect_modules(self):
>         # Ensure that /usr/local is always used
>         add_dir_to_list(self.compiler.library_dirs, '/opt/local/lib')
>         add_dir_to_list(self.compiler.include_dirs, '/opt/local/include')
> 
>   - configure --prefix=/pt/p
>   - make
>   - make install
> 
> I'm happy now!

You are aware that under OSX one usually wants a so-called 
framework-build? It's an configure-option.

You don't need the --prefix then (unless you have another python2.6 
installed), and without the FW-build no UI-packages are useable.

Diez


From piet at cs.uu.nl  Sun Jul 26 07:50:57 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 26 Jul 2009 13:50:57 +0200
Subject: how can a child thread notify a parent thread its status?
References: <f2d89333-e3f7-486e-9fb7-024407a769b5@x25g2000prf.googlegroups.com>
	<923a982d-5cd6-41ba-b4f9-80b4e81b601f@y10g2000prf.googlegroups.com>
	<mailman.3720.1248558305.8015.python-list@python.org>
	<96ec583d-afc6-4c8e-b53f-d875611a9c55@t11g2000prh.googlegroups.com>
	<mailman.3725.1248571777.8015.python-list@python.org>
Message-ID: <m2tz0zd5ni.fsf@cs.uu.nl>

>>>>> MRAB <python at mrabarnett.plus.com> (M) wrote:

>M> scriptlearner at gmail.com wrote:
>>> I decided to go with one big log file, which will be shared by all
>>> threads (child and parent).  A log message Queue is used to store all
>>> log entries, and a customized logger thread will get log entries from
>>> the Queue.
>>> 
>>> #from the logger thread#
>>> def run(self):
>>> while self.flag == 1: #if the flag is set to 0, the logger
>>> thread should exit
>>> try:
>>> entry = self.q.get()
>>> except Empty:
>>> self.logger.debug('cant find any log entry')
>>> continue
>>> except:
>>> self.logger.error("Unexpected error:", sys.exc_info()
>>> [0])
>>> raise
>>> #do whatever that should be done
>>> self.logger.info("logger thread done") #should see this
>>> message in log file as well
>>> def off(self):
>>> self.logger.info('turning off flag')
>>> self.flag = 0
>>> 
>>> 
>>> #in parent thread#
>>> logItemQ.put('We are done, lets stop the logger now.')
>>> time.sleep(1) #it seems that the logger thread cannot exit if
>>> I put a sleep here
>>> myLog.off() #off is called successfully
>>> myLog.join()
>>> 
>>> 
>>> I put an off method to turn off a flag so the logger thread knows it
>>> should exit.  However, the last log message (the one 'We are done,
>>> lets stop the logger now.') won't be logged if I call myLog.off() and
>>> myLog.join() immediately.  So, I put a time.sleep(1) to make sure the
>>> logger thread has enough time to finish it's job.  Unfortunately, now
>>> the logger thread simply won't exit, and I don't see the message
>>> 'logger thread done'.  I can't figure out at which point it hangs,
>>> since I don't any new log entry but the thread simply won't exit.
>>> Am I taking a right approach by using a flag?  Should I lock the flag?

>M> self.q.get() will block if the queue is empty, so the Empty exception is
>M> never raised.

>M> What's happening is that the parent thread puts the final message into
>M> the queue, sleeps, and then clears the flag; meanwhile, the logging
>M> thread gets the message, writes it out, checks the flag, which is still
>M> set, and then tries to get the next message. The queue is empty, so the
>M> .get() blocks.

>M> The simplest solution is not to use a flag, but the sentinel trick. The
>M> parent thread can put, say, None into the queue after the last message;
>M> when the logging thread gets None, it knows it should terminate.

To the OP: a sleep will never do it because you can't be sure how long
the logging thread will lag behind. Most multithreaded `solutions' which
depend on timings are buggy.

If you have more than one thread writing to the log queue one sentinel
won't solve the problem. You would need as many sentinels as there are
threads, and the logger should count the sentinels which can have normal
messages between them. It may be a bit fragile to depend on the number
of threads especially when this number is dynamic. One solution would be
to have special StartLogging and StopLogging objects that are put in the
queue when a thread starts and finishes respectively. The logger can stop
then when the number of StopLogging objects equals the number of
StartLogging objects received and that number is greater than 0. This
presupposes that no new thread will be started after all the others have
finished. The StartLogging objects can also be put in the queue by the
parent when it starts up the threads, which may be more robust because
it has fewer timing dependencies.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From breamoreboy at yahoo.co.uk  Sun Jul 26 07:53:20 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Sun, 26 Jul 2009 12:53:20 +0100
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
	<NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>
Message-ID: <h4hg2l$kb7$1@ger.gmane.org>

Neil Hodgson wrote:
> casebash:
> 
>> I have searched this list and found out that Python doesn't have a
>> mutable string class (it had an inefficient one, but this was removed
>> in 3.0). Are there any libraries outside the core that offer this?
> 
>    I wrote a gap buffer implementation for Python 2.5 allowing
> character, unicode character and integer elements.
> 
> http://code.google.com/p/gapbuffer/
> 
>    Its not seen much use or any maintenance so is unlikely to work with
> Python 3.x.
> 
>    Neil

I tried this as a learning exercise and found slicing doesn't work 
correctly.

import gapbuffer
print gapbuffer.GapBuffer(range(10))[:]
GapBuffer('i')]

If my sleuthing is correct the problem is with these lines

ilow *= self->itemSize;
ihigh *= self->itemSize;

in GapBuffer_slice being computed before ilow and ihigh are compared to 
anything.

Python 2.6.2 32 bit Windows.

-- 
Kindest regards.

Mark Lawrence.



From helvinlui at gmail.com  Sun Jul 26 08:04:11 2009
From: helvinlui at gmail.com (Helvin)
Date: Sun, 26 Jul 2009 05:04:11 -0700 (PDT)
Subject: PyQt GUI
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>
	<7bj5ulF22b4ktU1@mid.uni-berlin.de>
	<mailman.2830.1247044998.8015.python-list@python.org> 
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com> 
	<mailman.2864.1247095779.8015.python-list@python.org>
	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>
	<mailman.2902.1247154895.8015.python-list@python.org>
	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>
	<16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com> 
	<mailman.3611.1248368602.8015.python-list@python.org>
Message-ID: <4ee78bf1-476d-4e41-b9da-c20297aad861@13g2000prl.googlegroups.com>

On Jul 24, 5:03?am, Robert Kern <robert.k... at gmail.com> wrote:
> On 2009-07-23 03:55, Helvin wrote:
>
> > I believe I now have vtkpython.exe. However, my 'import vtk' statement
> > in my python code is not working. The error says something like "no
> > module named vtk".
> > Where do I find modules for vtk inpyqt? Do they exist?
>
> There are no VTK modules inPyQtitself. ThePyQtsupport is in the vtk package
> which can be built with VTK itself. You will need to install VTK and the vtk
> package correctly in order to achieve this. vtkpython.exe is not going to help
> you. Ignore it. After you have built VTK, you need to do an extra step to
> install the vtk package to where your Python interpreter will be able to find it.
>
> Let's say that your build directory is c:\vtkbuild.
>
> ? ?cd \vtkbuild\Wrapping\Python
> ? ?python setup.py install
> ? ?cd \
>
> Now you should be able to import vtk from your normal Python interpreter. If you
> are still having problems, you will need to copy-and-paste exactly what you did
> and what error messages you got. Do not paraphrase error messages.
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
> ? that is made terrible by our own mad attempt to interpret it as though it had
> ? an underlying truth."
> ? ?-- Umberto Eco

Hi Robert,

I realised that vtkpython.exe works, if I drag and drop my .py file on
it. Ie, running my .py file using vtkpython.exe
But my python interpreter does not work with the python file. I have
tried what you suggested.
Below is what I typed in command line, as well as the error that it
produces.

C:\Qt\VTKbin7\Wrapping\Python>python setup.py install
Traceback (most recent call last):
  File "setup.py", line 138, in <module>
    raise "ERROR: Must specify BUILD_TYPE=<config-name> on command
line."
TypeError: exceptions must be classes or instances, not str

Is it just a small error with input format or something?

Thanks so much!
Helvin


From aahz at pythoncraft.com  Sun Jul 26 09:16:39 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 06:16:39 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
Message-ID: <h4hkvn$ef6$1@panix3.panix.com>

In article <h4gnmr$8cl$1 at news.eternal-september.org>,
Raffael Cavallaro  <raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com> wrote:
>On 2009-07-25 00:55:26 -0400, Carl Banks <pavlovevidence at gmail.com> said:
>>
>> But please don't put it on the same level as PHP.  Their situations
>> have almost nothing in common.
>
>Their situations have much in common; Python attracted programmers away 
>from (for example) C++, becuse python is easier to master; Then php 
>came along and attracted programmers away from (for example) python, 
>because php is easier to master.

No, Python attracted programmers away from C++ because it's easier to
write good programs in it, in less time.  There are plenty of expert C++
programmers who switched to Python; your thesis only applies to the
legions of people who found it difficult to learn C++ in the first place.

Moreover, AFAIK PHP never attracted people away from Python; Python was
not particularly popular when PHP was in its heyday.  PHP attracted
people away from Perl and Java and C++.

I'm curious, do you actually know Python at all?  Have you used it for a
serious project?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Sun Jul 26 09:31:06 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Sun, 26 Jul 2009 09:31:06 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<h4hkvn$ef6$1@panix3.panix.com>
Message-ID: <h4hm7q$6g2$1@news.eternal-september.org>

On 2009-07-26 09:16:39 -0400, aahz at pythoncraft.com (Aahz) said:

> There are plenty of expert C++
> programmers who switched to Python;

"plenty" is an absolute term, not a relative term. I sincerely doubt 
that the majority of python users were formerly *expert* C++ 
programmers.

> your thesis only applies to the
> legions of people who found it difficult to learn C++ in the first place.

No, my thesis applies to the overwhelming majority of programmers who 
found it more difficult to *master* (i.e., not merely use) C++ as 
opposed to mastering python. BTW, this is a *complement* not a dis; 
python is a better language than C++ precisely because it is more 
sensibly and elegantly designed than C++ and therefore easier to master.

php represents the same process but farther down the ladder, as it 
were. There's often a tradeoff between ease of mastery and power. 
python hits a sweet spot for many tasks and many programmers, 
especially as compared to C++ (or even lisp, which though more powerful 
than python is more difficult to master. lisp beats C++ on both counts 
imho - more powerful *and* easier to master). php hits a sweet spot 
only in a very restricted domain. Beyond that, it is clearly inferior 
to python which has greater power, but is more difficult to master.


-- 
Raffael Cavallaro



From pauljbarry3 at gmail.com  Sun Jul 26 10:29:44 2009
From: pauljbarry3 at gmail.com (Paul Barry)
Date: Sun, 26 Jul 2009 07:29:44 -0700 (PDT)
Subject: Can't get UDP example to work
Message-ID: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>

I'm trying to get one of the examples from Foundation of Python
Network Programming to work.  Specifically this is the UDP example
from Ch 3.  First there is the server:

#!/usr/bin/env python
# UDP Echo Server - Chapter 3 - udpechoserver.py
import socket, traceback, time

host = '127.0.0.1'                               # Bind to all
interfaces
port = 51423

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host, port))

while 1:
    try:
        message, address = s.recvfrom(8192)
        print "Got message '%s' from %s" % (message, address)

        # Echo it back
        s.sendto(message, address)
        print "Sent response to '%s'" % (address,)

    except (KeyboardInterrupt, SystemExit):
        raise
    except:
        traceback.print_exc()

Next I have a client written in Ruby, which works.  I am posting thing
not to start a Ruby/Python flame war, but to simply prove that the
server works and there are no weird networking issues that would
prevent the Python client from working.  The Ruby code is:

#!/usr/bin/env ruby
require 'socket'

socket = UDPSocket.new
socket.connect ARGV[0], ARGV[1]

puts "Enter data to transmit: "
data = STDIN.gets.chomp

socket.send data, 0
puts "Looking for replies; press Ctrl-C or Ctrl-Break to stop."

loop do
  buf = socket.recvfrom(2048)
  puts buf.first
end

When I start the server and run that, the output looks like this:

$ ch02/udp.rb 127.0.0.1 51423
Enter data to transmit:
foobar
Looking for replies; press Ctrl-C or Ctrl-Break to stop.
foobar

Now, when I try the python example:

#!/usr/bin/env python
# UDP Example - Chapter 2 - udp.py

import socket, sys

host = sys.argv[1]
textport = sys.argv[2]

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
try:
    port = int(textport)
except ValueError:
    # That didn't work.  Look it up instead.
    port = socket.getservbyname(textport, 'udp')

s.connect((host, port))
print "Enter data to transmit: "
data = sys.stdin.readline().strip()
s.sendall(data)

print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
while 1:
    buf = s.recvfrom(2048)
    sys.stdout.write(buf[0])

I don't ever get a response:

$ ch02/udp.py 127.0.0.1 51423
Enter data to transmit:
foobar
Looking for replies; press Ctrl-C or Ctrl-Break to stop.

The server sees the message and says it has sent a reply:

Got message 'foobar' from ('127.0.0.1', 49623)
Sent response to '('127.0.0.1', 49623)'

Any ideas as to why this doesn't work?




From michael at stroeder.com  Sun Jul 26 10:59:42 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Sun, 26 Jul 2009 16:59:42 +0200
Subject: ANN: python-ldap-2.3.9
Message-ID: <mailman.3769.1248697213.8015.python-announce-list@python.org>

Find a new release of python-ldap:

  http://www.python-ldap.org/

python-ldap provides an object-oriented API to access LDAP directory
servers from Python programs. It mainly wraps the OpenLDAP 2.x libs for
that purpose. Additionally it contains modules for other LDAP-related
stuff (e.g. processing LDIF, LDAPURLs and LDAPv3 schema).

Ciao, Michael.

-- 
Michael Str?der
E-Mail: michael at stroeder.com
http://www.stroeder.com

----------------------------------------------------------------

Released 2.3.9 2009-07-26

Changes since 2.3.8:

Lib/
* All modules (ldap, ldif, dsml and ldapurl) have common version number now
* Non-exported function ldif.needs_base64() was abandoned and is now
  implemented as method LDIFWriter._needs_base64_encoding().
  This allows sub-classes of LDIFWriter to implement determining whether
  attribute values have to be base64-encoded in a different manner and is
  the same approach like in class dsml.DSMLWriter.
* LDAPUrlExtension._parse() now gracefully handles LDAP URL extensions
  without explicit exvalue as being set with implicit value None.

Modules/
* New LDAP option constant ldap.OPT_X_SASL_NOCANON supported
  in LDAPObject.get/set_option()


From python at mrabarnett.plus.com  Sun Jul 26 11:07:40 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 26 Jul 2009 16:07:40 +0100
Subject: Can't get UDP example to work
In-Reply-To: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
Message-ID: <4A6C713C.8050806@mrabarnett.plus.com>

Paul Barry wrote:
> I'm trying to get one of the examples from Foundation of Python
> Network Programming to work.  Specifically this is the UDP example
> from Ch 3.  First there is the server:
> 
> #!/usr/bin/env python
> # UDP Echo Server - Chapter 3 - udpechoserver.py
> import socket, traceback, time
> 
> host = '127.0.0.1'                               # Bind to all
> interfaces
> port = 51423
> 
> s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
> s.bind((host, port))
> 
> while 1:
>     try:
>         message, address = s.recvfrom(8192)
>         print "Got message '%s' from %s" % (message, address)
> 
>         # Echo it back
>         s.sendto(message, address)
>         print "Sent response to '%s'" % (address,)
> 
>     except (KeyboardInterrupt, SystemExit):
>         raise
>     except:
>         traceback.print_exc()
> 
> Next I have a client written in Ruby, which works.  I am posting thing
> not to start a Ruby/Python flame war, but to simply prove that the
> server works and there are no weird networking issues that would
> prevent the Python client from working.  The Ruby code is:
> 
> #!/usr/bin/env ruby
> require 'socket'
> 
> socket = UDPSocket.new
> socket.connect ARGV[0], ARGV[1]
> 
> puts "Enter data to transmit: "
> data = STDIN.gets.chomp
> 
> socket.send data, 0
> puts "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> 
> loop do
>   buf = socket.recvfrom(2048)
>   puts buf.first
> end
> 
> When I start the server and run that, the output looks like this:
> 
> $ ch02/udp.rb 127.0.0.1 51423
> Enter data to transmit:
> foobar
> Looking for replies; press Ctrl-C or Ctrl-Break to stop.
> foobar
> 
> Now, when I try the python example:
> 
> #!/usr/bin/env python
> # UDP Example - Chapter 2 - udp.py
> 
> import socket, sys
> 
> host = sys.argv[1]
> textport = sys.argv[2]
> 
> s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> try:
>     port = int(textport)
> except ValueError:
>     # That didn't work.  Look it up instead.
>     port = socket.getservbyname(textport, 'udp')
> 
> s.connect((host, port))
> print "Enter data to transmit: "
> data = sys.stdin.readline().strip()
> s.sendall(data)
> 
> print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> while 1:
>     buf = s.recvfrom(2048)
>     sys.stdout.write(buf[0])
> 
> I don't ever get a response:
> 
> $ ch02/udp.py 127.0.0.1 51423
> Enter data to transmit:
> foobar
> Looking for replies; press Ctrl-C or Ctrl-Break to stop.
> 
> The server sees the message and says it has sent a reply:
> 
> Got message 'foobar' from ('127.0.0.1', 49623)
> Sent response to '('127.0.0.1', 49623)'
> 
> Any ideas as to why this doesn't work?
> 
It works on my PC (Python 2.6.2, Windows XP Pro, service pack 3).


From robert.avery at gmail.com  Sun Jul 26 11:09:02 2009
From: robert.avery at gmail.com (Robert Avery)
Date: Sun, 26 Jul 2009 08:09:02 -0700 (PDT)
Subject: 'Registry' or 'Preference' settings in Mac Python
Message-ID: <35258dc9-941d-42ec-9c35-9361d0c70da7@n11g2000yqb.googlegroups.com>

Is there any way for me to save some sort of global preference for
python that I can read/write at runtime that doesn't involve me
explicitly creating a file?  It may create a file underneath, but I
don't want some path hard coded to my routine.

In Windows, the Registry serves this purpose.  Is there something
similar for Mac?


From deets at nospam.web.de  Sun Jul 26 11:09:26 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Sun, 26 Jul 2009 17:09:26 +0200
Subject: cgi.fieldstorage()
In-Reply-To: <13ed9818-aacd-4260-800b-a04177e13681@n11g2000yqb.googlegroups.com>
References: <b0dc0145-01bf-431d-88a9-b8041bb94e18@24g2000yqm.googlegroups.com>
	<7cu9hhF29gt65U1@mid.uni-berlin.de>
	<f765a487-d8b4-4de6-bcd2-2227b13438e7@k6g2000yqn.googlegroups.com>
	<7cv268F29q0j5U1@mid.uni-berlin.de>
	<13ed9818-aacd-4260-800b-a04177e13681@n11g2000yqb.googlegroups.com>
Message-ID: <7d39t9F2963rqU1@mid.uni-berlin.de>

gert schrieb:
> On Jul 25, 2:33 am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> gert schrieb:
>>
>>> On Jul 24, 7:32 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>>>> gert schrieb:
>>>>> this is a non standard way to store multi part post data on disk
>>>>> def application(environ, response):
>>>>>     with open('/usr/httpd/var/wsgiTemp','w') as f:
>>>>>         while True:
>>>>>             chunk = environ['wsgi.input'].read(8192).decode('latin1')
>>>>>             if not chunk: break
>>>>>             f.write(chunk)
>>>>>     response('200 OK',[])
>>>>>     return ['complete']
>>>>> my question is how do i handle the file, so i can shuffle it into a db
>>>>> using small chunks of memorie ?
>>>> I don't think that's possible with the current DB-API. There is no
>>>> stream-based BLOB-interface (as e.g. JDBC offers).
>>>> So the answer certainly depends on your used RDBMS. For oracle, you
>>>> would be lucky:
>>>> http://cx-oracle.sourceforge.net/html/lob.html
>>>> Other adapters I don't know about.
>>> sqlite :) ok let say for now it would be impossible on a db level, but
>>> before i reach the impossible, i still need to parse the file to
>>> prepare the chunks. How do i do that ? How do i get the chunks without
>>> loading the hole file into memorie ?
>> It's memory - memorie might be some nice dutch girl you know :)
>>
>> Apart from that, your code above does exactly that - reads the data
>> chunkwise. If the WSGI-implementation works proper, this will be the
>> socket's input stream, so there is no memory overhead involved.
>>
>> Now of course if you want to have a multi-pass processing of the file
>> without putting it into memory, then you need to save it to the harddisk
>> befor.
>>
>> But honestly - we are talking about a web-application here. My
>> DSL-connection has 1 MBit upstream, the average server has at least 2GB
>> of memory available - so we are talking 20000 seconds uploading time to
>> fill that memory. Which is about 5 hours. And you are decoding the data
>> to a certain decoding, so we are not talking about binary data here -
>> are you really sure memory is an issue?
>>
> 
> What about some http upload resume features ?

What has that todo with reading data into memory or not? Of course you 
can create continous uploads with HTTP, but a single HTTP-request is a 
single HTTP-request. You can store the requests into individual blobs, 
and then when the overall file upload is finished, concatenate these. If 
you like. Or not, if you don't care, as you can as easily serve them 
even as one stream from those various chunks.

But all of this has nothing todo with the need to not load POST-data 
into memory. This only becomes a problem if you are expecting uploads in 
the hundreds of megabytes.

Diez


From petite.abeille at gmail.com  Sun Jul 26 11:18:17 2009
From: petite.abeille at gmail.com (Petite Abeille)
Date: Sun, 26 Jul 2009 17:18:17 +0200
Subject: 'Registry' or 'Preference' settings in Mac Python
In-Reply-To: <35258dc9-941d-42ec-9c35-9361d0c70da7@n11g2000yqb.googlegroups.com>
References: <35258dc9-941d-42ec-9c35-9361d0c70da7@n11g2000yqb.googlegroups.com>
Message-ID: <68879AA8-CC01-4CA1-815F-88C0DC0F0181@gmail.com>


On Jul 26, 2009, at 5:09 PM, Robert Avery wrote:

> In Windows, the Registry serves this purpose.  Is there something
> similar for Mac?

http://developer.apple.com/documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/Reference/Reference.html

http://developer.apple.com/documentation/CoreFoundation/Reference/CFPreferencesUtils/Reference/reference.html

http://developer.apple.com/documentation/CoreFoundation/Conceptual/CFPreferences/CFPreferences.html

--
PA.
http://alt.textdrive.com/nanoki/



From aahz at pythoncraft.com  Sun Jul 26 11:44:02 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 08:44:02 -0700
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
	<h4av5n$p1l$1@panix3.panix.com>
	<mailman.3648.1248429993.8015.python-list@python.org>
Message-ID: <h4htk2$fmb$1@panix3.panix.com>

In article <mailman.3648.1248429993.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>En Thu, 23 Jul 2009 21:27:35 -0300, Aahz <aahz at pythoncraft.com> escribi?:
>> In article <mailman.3561.1248307942.8015.python-list at python.org>,
>> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>>>
>>> NLMPI
>>
>> What?
>
>IHNFI

What?  Abbreviations are fine, but if someone asks you about one, it
would be nice to just expand it instead of replying with another
abbreviation.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From victorsubervi at gmail.com  Sun Jul 26 11:48:29 2009
From: victorsubervi at gmail.com (Victor Subervi)
Date: Sun, 26 Jul 2009 12:48:29 -0300
Subject: Cannot Get Form To Work
In-Reply-To: <h4a513$dus$1@ger.gmane.org>
References: <4dc0cfea0907230846g4f593219t308c64eec4943f93@mail.gmail.com>
	<h4a513$dus$1@ger.gmane.org>
Message-ID: <4dc0cfea0907260848n1c59793bwd9f2dc1be46e66f1@mail.gmail.com>

Oops. My bad. I did in fact have this line of code before calls to form:

form = cgi.FieldStorage()

I changed the except command from "pass" to "print sys.exc_info()" as per
your suggestion. Still, however, the form just renews itself without
offering any information whatsoever. You can see this here, if you like:
http://13gems.com/test-Calculators_frame.py
TIA,
beno

On Thu, Jul 23, 2009 at 2:01 PM, Dennis Lee Bieber <wlfraed at ix.netcom.com>wrote:

> On Thu, 23 Jul 2009 12:46:16 -0300, Victor Subervi
> <victorsubervi at gmail.com> declaimed the following in
> gmane.comp.python.general:
>
> > sent. Here again is the code:
> >
> > from primeNumbers import primeNumbers
> >
> > try:
> >  lang = form.getfirst('lang', 'en')
>
>         This code is incomplete -- where is "form" created? I see no
> "import"s that might define such...
>
> >  browser = form.getfirst('browser', 'all')
> >  site = form.getfirst('site', 'bridge')
> >  num = form.getfirst('num','')
> > except:
> >  pass
>
>         Since there is no such thing as "form" in the code you posted, the
> first "form.getfirst()" operation will raise an exception. That
> exception is then being ignored by this "pass".
>
>        I'd suggest moving the code that outputs the HTTP response header
> and the HTML prelude material to the top, then replace "pass" with
> something that prints actual exception information (the stuff from
> sys.exc_info() )
> --
>        Wulfraed        Dennis Lee Bieber               KD6MOG
>        wlfraed at ix.netcom.com           wulfraed at bestiaria.com
>                HTTP://wlfraed.home.netcom.com/
>        (Bestiaria Support Staff:               web-asst at bestiaria.com)
>                HTTP://www.bestiaria.com/
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090726/0b190933/attachment-0001.html>

From sjmachin at lexicon.net  Sun Jul 26 11:51:39 2009
From: sjmachin at lexicon.net (John Machin)
Date: Sun, 26 Jul 2009 08:51:39 -0700 (PDT)
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
	<88e8ea19-7106-406a-a531-88c2b6893987@y7g2000yqa.googlegroups.com>
Message-ID: <c7231b06-e619-4ac5-9342-66c164c31595@p10g2000prm.googlegroups.com>

On Jul 23, 11:53?am, Paul McGuire <pt... at austin.rr.com> wrote:
> On Jul 22, 5:43?pm, Filip <pink... at gmail.com> wrote:

>
> # Needs re.IGNORECASE, and can have tag attributes, such as <BR
> CLEAR="ALL">
> line_break_re = re.compile('<br\/?>', re.UNICODE)

Just in case somebody actually uses valid XHTML :-) it might be a good
idea to allow for <br />

> # what about HTML entities defined using hex syntax, such as &#xxxx;
> amp_re = re.compile('\&(?![a-z]+?\;)', re.UNICODE | re.IGNORECASE)

What about the decimal syntax ones? E.g. not only &nbsp; and &#xa0;
but also &#160;

Also, entity names can contain digits e.g. &sup1; &frac34;


From aahz at pythoncraft.com  Sun Jul 26 11:55:18 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 08:55:18 -0700
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au> <87ljmogglz.fsf@benfinney.id.au>
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
	<056f629b-aa63-458a-ae16-ac40a759e446@h11g2000yqb.googlegroups.com>
Message-ID: <h4hu96$8hs$1@panix3.panix.com>

In article <056f629b-aa63-458a-ae16-ac40a759e446 at h11g2000yqb.googlegroups.com>,
Shai  <shai at platonix.com> wrote:
>
>class DocInherit(object):
>    """
>    Docstring inheriting method descriptor
>
>    The class itself is also used as a decorator
>    """

Nice!  Maybe stick this on the Cookbook?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From piet at cs.uu.nl  Sun Jul 26 12:13:22 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Sun, 26 Jul 2009 18:13:22 +0200
Subject: Why doesn't `from pkg import mod' work after `del pkg.mod'?
References: <2a32df38-3b3e-4c50-b5c7-accd1ae978c4@z34g2000vbl.googlegroups.com>
	<m2iqhgex8w.fsf@cs.uu.nl>
	<ef5b3dbe-92ab-45cb-a150-f8a921b68c71@r24g2000vbn.googlegroups.com>
Message-ID: <m2ab2rcti5.fsf@cs.uu.nl>

>>>>> ryles <rylesny at gmail.com> (r) wrote:

>r> On Jul 25, 8:57?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>>> >>>>> ryles <ryle... at gmail.com> (r) wrote:
>>> >r> According tohttp://www.python.org/doc/essays/packages.html:
>>> >r> "The import statement first tests whether the item is defined in the
>>> >r> package; if not, it assumes it is a module and attempts to load it."
>>> >r> However, I've noticed that once a module is imported using the
>>> >r> `from pkg import mod' syntax, if its name is deleted from the
>>> >r> package namespace then subsequent imports with `from' will fail.
>>> 
>>> This is incorrectly stated. Also on the initial import it will fail, not
>>> just on subsequent imports.
>>> 
>>> piet$ python
>>> Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39)
>>> [GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin
>>> Type "help", "copyright", "credits" or "license" for more information.
>>> from pkg import _impl
>>> 
>>> _impl # this is from a print statement in _impl to show that it did import
>>> Traceback (most recent call last):
>>> ? File "<stdin>", line 1, in <module>
>>> ImportError: cannot import name _impl
>>> 

>r> Well, since __init__.py is executed first, I would regard it as
>r> causing the initial (successful) import, and yours being the
>r> subsequent one, so that the "initial" import does not fail, the
>r> subsequent one does. Wording aside, though, I think we are on the same
>r> page here.

I was talking about the 'from pkg import _impl' statements because I
thought that's what we were talking about. Of course this does an
implicit 'import pkg' first, but that doesn't fail. In your OP you were
also talking about `from pkg import mod' imports and said that the
subsequent ones of these fails. I noticed that also the first one of
these would fail.

>>> 
>>> According to the documentation
>>> <http://docs.python.org/library/functions.html#__import__> the statement
>>> from pkg import _impl
>>> 
>>> _temp = __import__('pkg', globals(), locals(), ['_impl'], -1)
>>> _impl = _temp._impl
>>> 
>>> This fails because _temp (the imported module) doesn't have a binding
>>> for _impl because you deleted it.

>r> But supposing we hadn't deleted it, and __init__.py didn't import
>r> _impl, there would still be no binding. Yet the importer would still
>r> import and make the module available (presumably it "knows" to do this
>r> since it was not already in sys.modules). The question really is that
>r> since in our example pkg._impl is still in sys.modules, why won't the
>r> importer add it to the pkg namespace again as it previous had? I would
>r> imagine this is either by design, or is a case that was never
>r> considered.

Yes, that is also something I don't understand.

>>> for _impl because you deleted it. By the way, if you have a `normal'
>>> package that doesn't do anything with the name _impl, after the import
>>> the pkg module namespace will have got a binding for _impl although it is not
>>> in your code. It will have been put there by the import code.

>r> Yes, this was noted further down in the original post with an example.

Sorry, I missed that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From bazwal at ftml.net  Sun Jul 26 12:22:53 2009
From: bazwal at ftml.net (Baz Walter)
Date: Sun, 26 Jul 2009 17:22:53 +0100
Subject: pyc files not automatically compiled on import
Message-ID: <4A6C82DD.8020005@ftml.net>

hello

i thought that python automatically compiled pyc files after a module is 
successfully imported. what could prevent this happening?


Python 2.6.1 (r261:67515, Apr 12 2009, 03:51:25)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
 >>> import os
 >>> os.mkdir('/home/baz/tmp/foo')
 >>> os.chdir('/home/baz/tmp/foo')
 >>> f = open('foo.py', 'w')
 >>> f.write('print "hello world"\n')
 >>> f.close()
 >>> os.listdir('.')
['foo.py']
 >>> import foo
hello world
 >>> os.listdir('.') # why no pyc file?
['foo.py']
 >>> import py_compile
 >>> py_compile.compile('foo.py')
 >>> os.listdir('.')
['foo.py', 'foo.pyc']



From fuzzyman at gmail.com  Sun Jul 26 12:44:14 2009
From: fuzzyman at gmail.com (Fuzzyman)
Date: Sun, 26 Jul 2009 09:44:14 -0700 (PDT)
Subject: pyc files not automatically compiled on import
References: <mailman.3739.1248625343.8015.python-list@python.org>
Message-ID: <d6c8d04c-ceef-48ad-a7fb-8be52e0a8a4b@s15g2000yqs.googlegroups.com>

On Jul 26, 5:22?pm, Baz Walter <baz... at ftml.net> wrote:
> hello
>
> i thought that python automatically compiled pyc files after a module is
> successfully imported. what could prevent this happening?
>
> Python 2.6.1 (r261:67515, Apr 12 2009, 03:51:25)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> ?>>> import os
> ?>>> os.mkdir('/home/baz/tmp/foo')
> ?>>> os.chdir('/home/baz/tmp/foo')
> ?>>> f = open('foo.py', 'w')
> ?>>> f.write('print "hello world"\n')
> ?>>> f.close()
> ?>>> os.listdir('.')
> ['foo.py']
> ?>>> import foo
> hello world
> ?>>> os.listdir('.') # why no pyc file?
> ['foo.py']
> ?>>> import py_compile
> ?>>> py_compile.compile('foo.py')
> ?>>> os.listdir('.')
> ['foo.py', 'foo.pyc']

Works for me I'm afraid (Mac OS X and Python 2.6).

Michael Foord
--
http://www.ironpythoninaction.com/


From roy at panix.com  Sun Jul 26 12:53:59 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 26 Jul 2009 12:53:59 -0400
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
Message-ID: <roy-51AEF5.12535926072009@news.panix.com>

In article 
<148abf0f-c9e4-4156-8f16-e4e5615d350b at s6g2000vbp.googlegroups.com>,
 Paul Barry <pauljbarry3 at gmail.com> wrote:

> host = '127.0.0.1'           # Bind to all interfaces

This threw me off the track for a little while.  The comment is wrong!  
You're not binding to all interfaces, you're binding specifically to the 
loopback interface.  For what you're doing, it's fine, but the comment is 
still wrong.

It's also a little weird that the example uses connect() and sendall().  
Those are TCP-ish type constructs.  They work with UDP sockets, but using 
them sort of obscures the fundamental datagram nature of UDP.

Well, enough of that.  The real problem seems to be right here:

> print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> while 1:
>     buf = s.recvfrom(2048)
>     sys.stdout.write(buf[0])

Try adding sys.stdout.flush(), and it should work.  Or change it to print.

I've never seen this book, but if this code really is verbatim from the 
book, I'm not very impressed.


From __peter__ at web.de  Sun Jul 26 13:07:30 2009
From: __peter__ at web.de (Peter Otten)
Date: Sun, 26 Jul 2009 19:07:30 +0200
Subject: pyc files not automatically compiled on import
References: <mailman.3739.1248625343.8015.python-list@python.org>
Message-ID: <h4i2fu$4p7$00$1@news.t-online.com>

Baz Walter wrote:

> i thought that python automatically compiled pyc files after a module is
> successfully imported. what could prevent this happening?
> 
> 
> Python 2.6.1 (r261:67515, Apr 12 2009, 03:51:25)
> [GCC 4.3.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>  >>> import os
>  >>> os.mkdir('/home/baz/tmp/foo')
>  >>> os.chdir('/home/baz/tmp/foo')
>  >>> f = open('foo.py', 'w')
>  >>> f.write('print "hello world"\n')
>  >>> f.close()
>  >>> os.listdir('.')
> ['foo.py']
>  >>> import foo
> hello world
>  >>> os.listdir('.') # why no pyc file?
> ['foo.py']
>  >>> import py_compile
>  >>> py_compile.compile('foo.py')
>  >>> os.listdir('.')
> ['foo.py', 'foo.pyc']

You did not set the PYTHONDONTWRITEBYTECODE environment variable in a former 
life, or did you?



From Tom.sully at gmx.com  Sun Jul 26 13:13:44 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 10:13:44 -0700 (PDT)
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org> 
	<7d2nfnF29tk6fU1@mid.uni-berlin.de>
Message-ID: <cfa3dd46-8938-49dd-acb9-8ba6c9a6420b@o6g2000yqj.googlegroups.com>

Sorry for not providing enough information - and Rhodri, for sending
my second message I used the GMX webmail client rather than my usual
Linux client as I was testing it on windows. That must have screwed it
up, I need to download Thunderbird on Mozzila.

The thing that was messing it up was that the endlines are handled
differently on each each OS, so I changed the code to strip the
endlines to be:

    if os.name == "nt":
        s = sauce.rstrip("\r\n")
    else:
        s = sauce.replace("\n", "")

This works fine now, (os.name returns nt on windows and posix on
linux)
Thanks for the help, and sorry for slow response and lack of detail,
I'm still trying to get used to this usenet thing :P

--
print "Tom"


From qauzzix at gmail.com  Sun Jul 26 13:48:27 2009
From: qauzzix at gmail.com (Qauzzix)
Date: Sun, 26 Jul 2009 10:48:27 -0700 (PDT)
Subject: How do I generate dia diagrams from python source code?
References: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
	<mailman.3705.1248510681.8015.python-list@python.org>
Message-ID: <b0b7be72-7003-45d5-b8a5-1e74658b4901@32g2000yqj.googlegroups.com>

On Jul 25, 8:31?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Fri, 24 Jul 2009 17:52:47 -0300, Qauzzix <qauz... at gmail.com> escribi?:
>
> > Since I have been usingdiato make my UML diagrams. I also found an
> > util named dia2code that generates python code fromdiadiagram. Now
> > that I have that option I really want to find a way to generatedia
> > diagram from existing code and/or maintain my diagrams.
>
> > I have been googling ?like crazy trying to find a way but with no
> > luck. Anyone here know how to do this?
>
> SPE does that:http://pythonide.stani.be/
>
> --
> Gabriel Genellina

I think You are misunderstanding my question. I downloaded SPE and I
have been trying it out. It has an UML featus but in no way I can see
can I export it to be used by DIA the diagram editor. I could export
it as an image, nothing more. There exists many apps for extracting
UML diagrams from Python source but I need it to conform with DIA.


From gallium.arsenide at gmail.com  Sun Jul 26 13:54:52 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Sun, 26 Jul 2009 10:54:52 -0700 (PDT)
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org> 
	<7d2nfnF29tk6fU1@mid.uni-berlin.de>
	<cfa3dd46-8938-49dd-acb9-8ba6c9a6420b@o6g2000yqj.googlegroups.com>
Message-ID: <2abd5ecb-6fed-4763-9563-2caf63ca3c15@r25g2000vbn.googlegroups.com>

On Jul 26, 1:13?pm, Tom <Tom.su... at gmx.com> wrote:
> The thing that was messing it up was that the endlines are handled
> differently on each each OS, so I changed the code to strip the
> endlines to be:
>
> ? ? if os.name == "nt":
> ? ? ? ? s = sauce.rstrip("\r\n")
> ? ? else:
> ? ? ? ? s = sauce.replace("\n", "")

Well, this is doing two different things.  When os.name is 'nt', you
are getting rid of all *trailing* CRLFs.  Otherwise, you are getting
rid of all LFs *anywhere in the string*.  (Even if it so happens sauce
will only ever have LFs at the end, it's still better to use the
method that is closest to your intended meaning.)

Personally, I prefer using sauce.rstrip() with no parameters (one of
the suggestions Rhodri mentioned) if it's not important to preserve
trailing spaces, since this will work regardless of end-of-line style
(and typically, trailing spaces, tabs, etc. are undesirable anyway).

John


From aahz at pythoncraft.com  Sun Jul 26 13:56:54 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 10:56:54 -0700
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org>
Message-ID: <h4i5d6$mql$1@panix3.panix.com>

In article <mailman.3714.1248551656.8015.python-list at python.org>,
Tom  <tom.sully at gmx.com> wrote:
>
>I have an annoying problem. While I mainly use Linux when I distribute
>this program to friends and on the internet, it'll get used on Windows.
>So, I tested my python program on my Windows Vista dual boot, running
>the same version of python (2.6) as my Linux, and got an error at the
>following code.
>
>s = sauce.replace("\n", "")
>
>Sauce is a string, read from a file, that I need to remove newlines
>from. This code works fine in Linux, but not in Windows. rstrip("\n")
>won't work for me, so anybody know how to get this working on Windows?

Use open(fname, 'U')
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"At Resolver we've found it useful to short-circuit any doubt and just        
refer to comments in code as 'lies'. :-)"
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


From martin at v.loewis.de  Sun Jul 26 14:03:39 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 20:03:39 +0200
Subject: C-API, tp_dictoffset vs tp_members
In-Reply-To: <7d2mu7F27a9tbU1@mid.uni-berlin.de>
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
	<7d2mu7F27a9tbU1@mid.uni-berlin.de>
Message-ID: <4a6c9a7c$0$12532$9b622d9e@news.freenet.de>

>>> I have a predefined set of members, some of which are optional.
>> Having optional fields is also a good reason.
> 
> What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then?

Right - this works for optional objects. However, it can't possibly
work for any of the other fields.

>  I would
>  have though that the former describes an optional field, because the
>  behaviour of accessing it when it is NULL is the same as accessing a
>  nonexistent field. However, I see that it still appears in the dir()
>  output even if it is NULL, so it seems I'm misunderstanding this.

I suppose that's because there will still be a descriptor for the field
in the class.

> The 'example_attribute' can be accessed, but it is not visible in the
> dir() output. The code for this is below.

I see. So you do need a tp_members list:

static PyMemberDef example_members[] = {
     {"__dict__", T_OBJECT, offsetof(Example, dict), READONLY},
     {0}
};

Perhaps dir() should know about tp_dictoffset, but alas, it doesn't.

Regards,
Martin


From vivainio at gmail.com  Sun Jul 26 14:20:59 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Sun, 26 Jul 2009 11:20:59 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
	<slrnh6hfrp.dgi.nick@irishsea.home.craig-wood.com>
Message-ID: <69c8f3be-cc84-48e5-9969-ef9e87836094@e27g2000yqm.googlegroups.com>

On Jul 23, 11:29?pm, Nick Craig-Wood <n... at craig-wood.com> wrote:

> > ?The syntax would be something like:
>
> > ?def work():
>
> > ? ?showstatus("building")
> > ? ?r = yield runshell("make")
> > ? ?showstatus("installing")
> > ? ?r = yield runshell("make install")
> > ? ?showstatus("Success")
>
> > ?mygui.startwork(work)
> > ?# returns immediately, runs work() gradually in the background.
>
> > ?The catch is that showstatus() would need to be run in the mainloop,
> > ?so running the whole thing in a thread is a no-go.
>
> > ?I imagine runshell() would be implemented in terms of QProcess, or
> > ?subprocess.Popen/os.system and a worker thread.
>
> > ?Anyone done this already, or do I have to roll my own?
>
> You might want to look at twisted, in particular
>
> ?http://twistedmatrix.com/trac/wiki/DeferredGenerator

Indeed, DeferredGenerator looks pretty much what I'm interested in,
thanks for the pointer. Unfortunately, it has the big Twisted
dependency. That's probably not a showstopper, but Twisted requires a
degree of buy-in when something smaller would do.


From santhosh.vkumar at gmail.com  Sun Jul 26 14:22:42 2009
From: santhosh.vkumar at gmail.com (Santhosh Kumar)
Date: Sun, 26 Jul 2009 23:52:42 +0530
Subject: Itext for Python
Message-ID: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com>

Hi all,           One of my cousin  suggested me to do a IText
PDF converter for python. Actually I heard that there is
no separate IText converter either we have to go for jython or GCJ with
wrapper. Instead of wrapping, my plan is to create a separate module with
Python and I am thinking of doing this in as my final year project also.
Kindly give me your suggestion.

        With anticipation,

SanthoshVKumar.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090726/f2162d8f/attachment-0001.html>

From nagle at animats.com  Sun Jul 26 14:24:48 2009
From: nagle at animats.com (John Nagle)
Date: Sun, 26 Jul 2009 11:24:48 -0700
Subject: Help understanding the decisions *behind* python? - immutable
	objects
In-Reply-To: <9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
Message-ID: <4a6c9ec0$0$1636$742ec2ed@news.sonic.net>

Beni Cherniavsky wrote:
> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
> wrote:
>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>
>>> My guess is that it was probably for optimization reasons long ago.
>>> I've never heard a *good* reason why Python needs both.
>> The good reason is the immutability, which lets you use
>> a tuple as a dict key.  
>>
> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
> wrote:
>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>
>>> My guess is that it was probably for optimization reasons long ago.
>>> I've never heard a *good* reason why Python needs both.
>> The good reason is the immutability, which lets you use
>> a tuple as a dict key.
>>
> The *technical* reason is immutability for dict keys.
> Dict could allow mutable objects as keys by comparing *by value*,
> making a copy on insertion and hashing the current value on lookup.
> Prior art: the 2.3 sets module allows mutable Sets as elements in
> Sets, by making ImmutableSet copies on insertion, and hashing Sets as
> if they are temporarily immutable on lookup.
> 
> This inspired PEP 351 and ambitious proposals to expand the approach
> to all Python with a copy-on-write scheme.  But these ideas were
> rejected, and the 2.4 builtin sets only allow frozenset elements.
> Half the reason is technical: copy-on-write and harder than it sounds,
> and without it you pay a performance price.
> 
> But the deeper reason is style: immutable types are convenient!
> The allow a pure-functional style of code, which can be simpler.
> Of course, sometimes an imperative style is simpler.  Depends on the
> problem.

     An interesting issue is Python objects, which are always mutable.
A "dict" of Python objects is allowed, but doesn't consider
the contents of the objects, just their identity (address). Only
built-in types are immutable; one cannot create a class of immutable objects.
So things like "frozenset" had to be built into the language.
A tuple is really a frozen list.  Arguably, frozen objects
should have been a general concept.  Conceptually, they're
simple - once "__init__" has run, there can be no more changes
to fields of the object.

     Compare the C++ approach, where you can have a "map" of
any object that defines the "<" operator.  Python has
"__cmp__" for objects, but built-in dictionaries don't use it.
Of course, one could create a "map" class in Python that
uses "__cmp__", which would allow dictionary-type operations
on arbitrary objects.

     There are some interesting uses for immutable objects in
multithreaded programs.  They can be shared between threads
without locking.  If it weren't for the infamous Global
Interpreter Lock, which basically limits Python programs to using
one CPU at a time, Python would have to deal with locking
in a more advanced way.  A system where immutable objects
can be shared and passed between threads, and mutable objects
must be "synchronized" (in the Java sense) to be shared would
be useful.

				John Nagle


From vivainio at gmail.com  Sun Jul 26 14:32:11 2009
From: vivainio at gmail.com (Ville M. Vainio)
Date: Sun, 26 Jul 2009 11:32:11 -0700 (PDT)
Subject: Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() 
	that doesn't block gui event loops
References: <fa64b0ce-e7de-4f8a-9b55-1ec8bf0ea677@h31g2000yqd.googlegroups.com>
	<4a65f0d8$0$1599$742ec2ed@news.sonic.net>
Message-ID: <ed3da964-c58e-498a-b301-e54980e54101@a26g2000yqn.googlegroups.com>

Apologies for the long subject line, here it is again:

"Pep 342 (val = yield MyGenerator(foo)), synchronous os.system() that
doesn't block gui event loops"

On Jul 21, 7:48?pm, John Nagle <na... at animats.com> wrote:

> > The idea:
>
> > To run functions that execute a series of system commands without
> > blocking the ui, *and* without adding state machine logic.
>
> ? ? At some level, there's going to be state machine logic.
> You need interlocking so that the user can't initiate
> simultaneous conflicting background operations from the GUI.

This belongs to the "I don't care" category, as you'd expect to have
only one operation like this on the flight at one time. The idea is to
allow making simple scripts that you execute from the gui, that *may*
need to access the gui objects at one point or another (so execution
has to happen in the main thread most of the time - apart from
blocking, long operations).


> ? ? The usual solution is to run the background operations
> in another thread, and have them put events on a queue
> read by the GUI task.

Yeah, and the receiving end of the "queue" here would be the same
block of statements that launched the request - that is, I want to
avoid having to create handler functions, and keep the program from
linear.


> ? ? You also have to work out how to cancel background operations,
> if they're going to be as big as a "make".

I think that is easy to accomplish with generators, provided that you
can let the long-lasting operation run to completion - just close()
the generator. If the long lasting computation was in a subprocess,
rather than a thread, it could be interrupted in a cleaner fashion
even.


From drobinow at gmail.com  Sun Jul 26 15:26:46 2009
From: drobinow at gmail.com (David Robinow)
Date: Sun, 26 Jul 2009 14:26:46 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4gnmr$8cl$1@news.eternal-september.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
Message-ID: <4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>

> This doesn't mean they're on the same level - in fact, if you read carefully
> you'll see my original post said as much: python attracted average
> programmers; php attracted mediocre programmers and even some
> non-programmers, which means that php is clearly a lesser language than
> python.
 I'm a mediocre programmer. Does this mean I should switch to PHP?


From bazwal at ftml.net  Sun Jul 26 15:30:12 2009
From: bazwal at ftml.net (Baz Walter)
Date: Sun, 26 Jul 2009 20:30:12 +0100
Subject: pyc files not automatically compiled on import
In-Reply-To: <h4i2fu$4p7$00$1@news.t-online.com>
References: <mailman.3739.1248625343.8015.python-list@python.org>
	<h4i2fu$4p7$00$1@news.t-online.com>
Message-ID: <4A6CAEC4.7020300@ftml.net>

Peter Otten wrote:
> You did not set the PYTHONDONTWRITEBYTECODE environment variable in a former 
> life, or did you?

thanks peter

no i didn't, but i've just discovered a script in /etc/profile.d that 
did. now i'll have to try to find out how that script got in there :-|



From dotancohen at gmail.com  Sun Jul 26 15:34:52 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Sun, 26 Jul 2009 22:34:52 +0300
Subject: Looking for a dream language: sounds like Python to me.
Message-ID: <880dece00907261234x684547f4g5272b211379a7ba1@mail.gmail.com>

Referring to this article:
http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/

The author, who is specifically looking for math-related functions, writes:
"""
The dream algorithm R&D tool would be similar to Matlab or Mathematica
but could be compiled to fast, efficient binaries similar to ANSI C
and would be available for all platforms. An integrated GUI builder
similar to Visual Basic and integrated network support would be
helpful.
"""

It looks to me like he is looking for Python.

-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From doomster at knuut.de  Sun Jul 26 15:39:17 2009
From: doomster at knuut.de (Ulrich Eckhardt)
Date: Sun, 26 Jul 2009 21:39:17 +0200
Subject: C-API, tp_dictoffset vs tp_members
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
	<7d2mu7F27a9tbU1@mid.uni-berlin.de>
	<4a6c9a7c$0$12532$9b622d9e@news.freenet.de>
Message-ID: <7d3pnaF29o57gU1@mid.uni-berlin.de>

"Martin v. L?wis" wrote:
>>>> I have a predefined set of members, some of which are optional.
>>> Having optional fields is also a good reason.
>> 
>> What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then?
> 
> Right - this works for optional objects. However, it can't possibly
> work for any of the other fields.

I have two members, one T_OBJECT and one T_OBJECT_EX. Both are NULL and both 
still appear in the dir() output. For one, accessing it returns 'None', for 
the other it raises an exception. I would have expected an element that is 
not accessible, not even 'None', to also not be visible in dir().

>>  I would have thought that the former describes an optional field,
>>  because the behaviour of accessing it when it is NULL is the same
>>  as accessing a nonexistent field. However, I see that it still
>>  appears in the dir() output even if it is NULL, so it seems I'm
>>  misunderstanding this.
> 
> I suppose that's because there will still be a descriptor for the
> field in the class.

So is that intentional or is it dir() that could be improved there? Should I 
file a bugreport?


Thanks for the tip with __dict__ in tp_members, that does the job!

Uli




From pauljbarry3 at gmail.com  Sun Jul 26 15:40:39 2009
From: pauljbarry3 at gmail.com (Paul Barry)
Date: Sun, 26 Jul 2009 12:40:39 -0700 (PDT)
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<roy-51AEF5.12535926072009@news.panix.com>
Message-ID: <2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a@p23g2000vbl.googlegroups.com>

On Jul 26, 12:53?pm, Roy Smith <r... at panix.com> wrote:
> In article
> <148abf0f-c9e4-4156-8f16-e4e5615d3... at s6g2000vbp.googlegroups.com>,
> ?Paul Barry <pauljbar... at gmail.com> wrote:
>
> > host = '127.0.0.1' ? ? ? ? ? # Bind to all interfaces
>
> This threw me off the track for a little while. ?The comment is wrong! ?
> You're not binding to all interfaces, you're binding specifically to the
> loopback interface. ?For what you're doing, it's fine, but the comment is
> still wrong.

You are right.  The example in the book actually has

host = ''

So the comment is correct.  In trying to debug what was going on, I
put 127.0.0.1 to see if that had something to do with it, which it
didn't.

>
> It's also a little weird that the example uses connect() and sendall(). ?
> Those are TCP-ish type constructs. ?They work with UDP sockets, but using
> them sort of obscures the fundamental datagram nature of UDP.
>
> Well, enough of that. ?The real problem seems to be right here:
>
> > print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> > while 1:
> > ? ? buf = s.recvfrom(2048)
> > ? ? sys.stdout.write(buf[0])
>
> Try adding sys.stdout.flush(), and it should work. ?Or change it to print.
>

Yes, that did the trick, thanks.  I should have thought of that, if I
would have just printed something after the recvfrom line I would have
realized it was no longer blocking and the problem was with getting
the client to print the data to stdout, not with getting a response
from the server.

> I've never seen this book, but if this code really is verbatim from the
> book, I'm not very impressed.

I like the book so far.  It's a little verbose, but I think that's
because he's trying to teach the concepts, rather than the write it
how you actually would in production.  In this case, I think he's
trying to illustrate how the UDP example compares to the TCP example
from the previous section, which is why he choose to keep the methods
the same.

But why not use

    print buf[0]

instead of

    sys.stdin.write(buf[0])

that much, I don't know.



From pauljbarry3 at gmail.com  Sun Jul 26 15:42:32 2009
From: pauljbarry3 at gmail.com (Paul Barry)
Date: Sun, 26 Jul 2009 12:42:32 -0700 (PDT)
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<mailman.3736.1248620831.8015.python-list@python.org>
Message-ID: <87ff9f36-30cb-4982-9730-7dcee491c0de@l2g2000vba.googlegroups.com>

On Jul 26, 11:07?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Paul Barry wrote:
> > I'm trying to get one of the examples from Foundation of Python
> > Network Programming to work. ?Specifically this is the UDP example
> > from Ch 3. ?First there is the server:
>
> > #!/usr/bin/env python
> > # UDP Echo Server - Chapter 3 - udpechoserver.py
> > import socket, traceback, time
>
> > host = '127.0.0.1' ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? # Bind to all
> > interfaces
> > port = 51423
>
> > s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> > s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
> > s.bind((host, port))
>
> > while 1:
> > ? ? try:
> > ? ? ? ? message, address = s.recvfrom(8192)
> > ? ? ? ? print "Got message '%s' from %s" % (message, address)
>
> > ? ? ? ? # Echo it back
> > ? ? ? ? s.sendto(message, address)
> > ? ? ? ? print "Sent response to '%s'" % (address,)
>
> > ? ? except (KeyboardInterrupt, SystemExit):
> > ? ? ? ? raise
> > ? ? except:
> > ? ? ? ? traceback.print_exc()
>
> > Next I have a client written in Ruby, which works. ?I am posting thing
> > not to start a Ruby/Python flame war, but to simply prove that the
> > server works and there are no weird networking issues that would
> > prevent the Python client from working. ?The Ruby code is:
>
> > #!/usr/bin/env ruby
> > require 'socket'
>
> > socket = UDPSocket.new
> > socket.connect ARGV[0], ARGV[1]
>
> > puts "Enter data to transmit: "
> > data = STDIN.gets.chomp
>
> > socket.send data, 0
> > puts "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
>
> > loop do
> > ? buf = socket.recvfrom(2048)
> > ? puts buf.first
> > end
>
> > When I start the server and run that, the output looks like this:
>
> > $ ch02/udp.rb 127.0.0.1 51423
> > Enter data to transmit:
> > foobar
> > Looking for replies; press Ctrl-C or Ctrl-Break to stop.
> > foobar
>
> > Now, when I try the python example:
>
> > #!/usr/bin/env python
> > # UDP Example - Chapter 2 - udp.py
>
> > import socket, sys
>
> > host = sys.argv[1]
> > textport = sys.argv[2]
>
> > s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
> > try:
> > ? ? port = int(textport)
> > except ValueError:
> > ? ? # That didn't work. ?Look it up instead.
> > ? ? port = socket.getservbyname(textport, 'udp')
>
> > s.connect((host, port))
> > print "Enter data to transmit: "
> > data = sys.stdin.readline().strip()
> > s.sendall(data)
>
> > print "Looking for replies; press Ctrl-C or Ctrl-Break to stop."
> > while 1:
> > ? ? buf = s.recvfrom(2048)
> > ? ? sys.stdout.write(buf[0])
>
> > I don't ever get a response:
>
> > $ ch02/udp.py 127.0.0.1 51423
> > Enter data to transmit:
> > foobar
> > Looking for replies; press Ctrl-C or Ctrl-Break to stop.
>
> > The server sees the message and says it has sent a reply:
>
> > Got message 'foobar' from ('127.0.0.1', 49623)
> > Sent response to '('127.0.0.1', 49623)'
>
> > Any ideas as to why this doesn't work?
>
> It works on my PC (Python 2.6.2, Windows XP Pro, service pack 3).

Doesn't work on a Mac with Python 2.5.1 or 2.6.2 unless you flush
stdout or change it to print.  Not sure why it would work on one
platform and not the other.


From Tom.sully at gmx.com  Sun Jul 26 15:45:10 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 12:45:10 -0700 (PDT)
Subject: Globalize all variables in function without knowing names.
Message-ID: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>

Does anyknow know how to do this? The reason I'm asking is because I'm
trying to make a mini-programming language for fun, and need to work
with variables.

The user types 'set NAME "DATA" ' or whatever else the variable is
going to be called/contain.

I have:
def variablework(varname, varset):
    exec("global "+varname) #DEFUNCT
    vars()[varname] = varset
    exec("print "+varname)   #Debug purposes only

This sets the variable (varname is the name of the variable, and
varset is the data for it to contain) all fine and dandy, but it is
local, and after some googling I realised that you can't globalised
variables using exec. So I think the next best thing would be to find
a way to globalize every variable in the function, but I don't know
how to do this. If there isn't a way of doing this, can someone
suggest another way of globalizing variable without knowing their
names?


From roy at panix.com  Sun Jul 26 16:31:43 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 26 Jul 2009 16:31:43 -0400
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<roy-51AEF5.12535926072009@news.panix.com>
	<2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a@p23g2000vbl.googlegroups.com>
Message-ID: <roy-21371D.16314326072009@news.panix.com>

In article 
<2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a at p23g2000vbl.googlegroups.com>,
 Paul Barry <pauljbarry3 at gmail.com> wrote:

> In this case, I think he's trying to illustrate how the UDP example 
> compares to the TCP example from the previous section, which is why he 
> choose to keep the methods the same.


I suppose, but I still think that's a confusing way to teach the 
differences between UDP and TCP.  The fundamental differences are:

1) TCP makes sure what you send gets there (for reasonably large values of 
"makes sure").  UDP just tosses stuff out onto the network and hopes for 
the best.

2) TCP is connection-oriented.  Connections must be explicitly set up 
before any data can flow, and once two sockets are connected, they can 
never be disconnected (short of tearing down the connection and starting 
again with two new sockets).  With UPD, every time you send data, you have 
to specify where it's going, and a given socket can be talking to many 
different remote endpoints on a packet-by-packet basis.

3) TCP is a stream protocol, which hides record boundaries; it is free to 
combine and/or split up your data into whatever packet boundaries it wants, 
and there is no way for the receiving end to discover where the boundaries 
are.  UDP, on the other hand, honors record boundaries; there is a 
one-to-one correspondence between each write (send, sendto) call at one and 
each read (recv, recvfrom) call at the other.

It's difficult to demonstrate #1 in a simple example, so I'll skip that.  
But, #2 and #3 are easy.

The example you gave uses connect() on a UDP socket.  That's not pointing 
out the differences between UDP and TCP, that's hiding them behind a 
strange corner of the API.  There really is no connection set up when you 
do connect() on a UDP socket; it's just a way of saying, "From now on, I'm 
going to skip telling you the destination of each individual datagram.  
Just use this destination from now on".  It saves moving a bit of data 
around, but it's not fundamentally a connection.

As for the stream/datagram distinction, sendall() is very much a stream 
creature.  It says, "Just keep banging out packets until you've managed to 
transmit the whole buffer".  That only makes sense in an environment where 
packet boundaries are meaningless.  Using it with UDP is sort of like 
saying, "Use as many packets as it takes, as long as that number is one".  
It's not not a concept that makes sense in a datagram world.  That it works 
at all on UDP is (IHMO) a mis-guided attempt at interface uniformity.

If I were writing an example on how to use UDP, I would leave out the 
connect() call, and use sendto() instead of sendall().  Once the student 
has those down, that's the time to talk about weird corner cases like how 
connect() and sendall() can be twisted to work with UDP sockets.  Or maybe 
not even bother.


From Tom.sully at gmx.com  Sun Jul 26 16:57:02 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 13:57:02 -0700 (PDT)
Subject: Removing newlines from string on windows (without replacing)
References: <mailman.3714.1248551656.8015.python-list@python.org> 
	<7d2nfnF29tk6fU1@mid.uni-berlin.de>
	<cfa3dd46-8938-49dd-acb9-8ba6c9a6420b@o6g2000yqj.googlegroups.com>
	<2abd5ecb-6fed-4763-9563-2caf63ca3c15@r25g2000vbn.googlegroups.com>
Message-ID: <d8b0cd0b-f96f-4a17-8240-50f8fb76a592@m11g2000yqh.googlegroups.com>

> (Even if it so happens sauce
> will only ever have LFs at the end, it's still better to use the
> method that is closest to your intended meaning.)

Oh, you're right. I'll change that now. I suppose removing all
endlines will be better, incase, somehow, endlines in the middle of
the line arrises.

> if it's not important to preserve trailing spaces

The way I parse the file currently splits away all whitespace later
on. While I could change this, I have a nice system worked out and my
code is working, so it's not top priority.


From python at mrabarnett.plus.com  Sun Jul 26 16:59:42 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Sun, 26 Jul 2009 21:59:42 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>	<4a6905b0$0$27110$a729d347@news.telepac.pt>	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>	<h4ctjv$bhj$1@news.eternal-september.org>	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
Message-ID: <4A6CC3BE.6060806@mrabarnett.plus.com>

David Robinow wrote:
>> This doesn't mean they're on the same level - in fact, if you read carefully
>> you'll see my original post said as much: python attracted average
>> programmers; php attracted mediocre programmers and even some
>> non-programmers, which means that php is clearly a lesser language than
>> python.
>  I'm a mediocre programmer. Does this mean I should switch to PHP?

If you're a mediocre programmer who knows you're mediocre, but wants to
improve and is willing to learn, then stick with Python. You'll get
better. :-)


From roy at panix.com  Sun Jul 26 17:04:23 2009
From: roy at panix.com (Roy Smith)
Date: Sun, 26 Jul 2009 17:04:23 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
Message-ID: <roy-F3FA5C.17042326072009@news.panix.com>

In article <h4gnmr$8cl$1 at news.eternal-september.org>,
 Raffael Cavallaro <raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com> 
 wrote:

> php is clearly a lesser language than python.

I'm as much of a Python bigot as anybody.  Likewise, I put down php for all 
the sorts of theoretical reasons people have been putting it down.  Not to 
mention that it looks like Perl, which is enough to make anybody go 
screaming in the other direction.

However, it's hard to argue with success.  A ton of very useful software 
has been written in php (including MediaWiki, which drives Wikipedia).  One 
needs to have a very highly developed sense of theoretical purity to look 
down their noses at the language that drives one of the highest volume web 
sites on the planet.


From gagsl-py2 at yahoo.com.ar  Sun Jul 26 17:06:48 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sun, 26 Jul 2009 18:06:48 -0300
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3561.1248307942.8015.python-list@python.org>
	<h4av5n$p1l$1@panix3.panix.com>
	<mailman.3648.1248429993.8015.python-list@python.org>
	<h4htk2$fmb$1@panix3.panix.com>
Message-ID: <op.uxo0xmydx6zn5v@gabriel.sleipnir-bsas>

En Sun, 26 Jul 2009 12:44:02 -0300, Aahz <aahz at pythoncraft.com> escribi?:
> In article <mailman.3648.1248429993.8015.python-list at python.org>,
> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>> En Thu, 23 Jul 2009 21:27:35 -0300, Aahz <aahz at pythoncraft.com>  
>> escribi?:
>>> In article <mailman.3561.1248307942.8015.python-list at python.org>,
>>> Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>>>>
>>>> NLMPI
>>>
>>> What?
>>
>> IHNFI
>
> What?  Abbreviations are fine, but if someone asks you about one, it
> would be nice to just expand it instead of replying with another
> abbreviation.

Ok, if you insist...

NLMPI = Ni La M?s Puta Idea.
IHNFI = I Have No Fucking Idea.

-- 
Gabriel Genellina



From martin at v.loewis.de  Sun Jul 26 17:24:43 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Sun, 26 Jul 2009 23:24:43 +0200
Subject: C-API, tp_dictoffset vs tp_members
In-Reply-To: <7d3pnaF29o57gU1@mid.uni-berlin.de>
References: <7cl194F28ojoqU1@mid.uni-berlin.de> <4A6C0DFC.4030702@v.loewis.de>
	<7d2mu7F27a9tbU1@mid.uni-berlin.de>
	<4a6c9a7c$0$12532$9b622d9e@news.freenet.de>
	<7d3pnaF29o57gU1@mid.uni-berlin.de>
Message-ID: <4A6CC99B.4070406@v.loewis.de>

>>>>> I have a predefined set of members, some of which are optional.
>>>> Having optional fields is also a good reason.
>>> What is the use of T_OBJECT_EX vs T_OBJECT in PyMemberDef then?
>> Right - this works for optional objects. However, it can't possibly
>> work for any of the other fields.
> 
> I have two members, one T_OBJECT and one T_OBJECT_EX. Both are NULL and both 
> still appear in the dir() output. For one, accessing it returns 'None', for 
> the other it raises an exception. I would have expected an element that is 
> not accessible, not even 'None', to also not be visible in dir().

I understood your expectation already. I maintain my theory that it
shows up because there is a descriptor on the class.

>> I suppose that's because there will still be a descriptor for the
>> field in the class.
> 
> So is that intentional or is it dir() that could be improved there? 

It's probably both.

> Should I file a bugreport?

Only if you can provide a patch also. My guess is that when you have
the patch completed, you might realize that it is not an improvement,
despite achieving what you wanted to achieve.

Regards,
Martin


From raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com  Sun Jul 26 17:41:31 2009
From: raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com (Raffael Cavallaro)
Date: Sun, 26 Jul 2009 17:41:31 -0400
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<roy-F3FA5C.17042326072009@news.panix.com>
Message-ID: <h4iivd$o3q$1@news.eternal-september.org>

On 2009-07-26 17:04:23 -0400, Roy Smith <roy at panix.com> said:

> One
> needs to have a very highly developed sense of theoretical purity to look
> down their noses at the language that drives one of the highest volume web
> sites on the planet.

It's nothing to do with theoretical purity and everything to do with 
practicality. php has a limited range of utility. Within that range, 
it's clearly quite useful. Python is useful for a greater range of 
tasks which makes it a more generally useful (and in this sense, 
better) language.


-- 
Raffael Cavallaro



From devent at deventm.org  Sun Jul 26 17:49:58 2009
From: devent at deventm.org (Erwin Mueller)
Date: Mon, 27 Jul 2009 07:49:58 +1000
Subject: How to comment constant values?
Message-ID: <200907270749.58845.devent@deventm.org>

Hello, I'm new to Python (using it for two months) and I wonder how can I 
comment the const. values with the doc-strings. I.e. if I have code:

>FRACTION_MIN = 1
>FRACTION_MAX = 10
>
>class Fraction(collections.MutableSequence):
>    '''Model a fraction with denominators.
>
>    It contains one ore more denomintors in a list for quick access.
>    The class is thread save, it uses a lock for all operations.
>    '''
>
>    def __init__(self):
>		# ...

The class and the methods can have doc-strings, but what about the const. 
values, FRACTION_MIN and FRACTION_MAX?

Thank you, Erwin.


From clp2 at rebertia.com  Sun Jul 26 18:06:29 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Sun, 26 Jul 2009 15:06:29 -0700
Subject: How to comment constant values?
In-Reply-To: <200907270749.58845.devent@deventm.org>
References: <200907270749.58845.devent@deventm.org>
Message-ID: <50697b2c0907261506o4c7b0a04t2e5155833f62be7e@mail.gmail.com>

On Sun, Jul 26, 2009 at 2:49 PM, Erwin Mueller<devent at deventm.org> wrote:
> Hello, I'm new to Python (using it for two months) and I wonder how can I
> comment the const. values with the doc-strings. I.e. if I have code:
>
>>FRACTION_MIN = 1
>>FRACTION_MAX = 10
>>
>>class Fraction(collections.MutableSequence):
>> ? ?'''Model a fraction with denominators.
>>
>> ? ?It contains one ore more denomintors in a list for quick access.
>> ? ?The class is thread save, it uses a lock for all operations.
>> ? ?'''
>>
>> ? ?def __init__(self):
>> ? ? ? ? ? ? ? # ...
>
> The class and the methods can have doc-strings, but what about the const.
> values, FRACTION_MIN and FRACTION_MAX?

Only modules, classes, and functions/methods can have docstrings
associated with them.
For anything else, you have to use comments; or you can mention them
in the docstrings of related things.

Cheers,
Chris
-- 
http://blog.rebertia.com


From Tom.sully at gmx.com  Sun Jul 26 18:07:08 2009
From: Tom.sully at gmx.com (Tom)
Date: Sun, 26 Jul 2009 15:07:08 -0700 (PDT)
Subject: Globalize all variables in function without knowing names.
References: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>
	<mailman.3748.1248642820.8015.python-list@python.org>
Message-ID: <5649dfb8-01a6-490d-bf30-b4a5206e644e@j21g2000yqe.googlegroups.com>

Ah, thanks for that Dennis. I have a system already figured out where
the user manually pre-enters all the variables into a .py file, which
obviously isn't very efficient. The language isn't going to be used
much except by me, so I suppose I'll just work with that until I look
more into dictionaries, but I'm still beginning Python, and before
that the only coding I did was a little bit of C++, so I'll wait up
for that :P


From hekevintran at gmail.com  Sun Jul 26 18:24:25 2009
From: hekevintran at gmail.com (Kevin)
Date: Sun, 26 Jul 2009 15:24:25 -0700 (PDT)
Subject: Error in compiling Python on OS X
Message-ID: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>

I am trying to compile Python 2.6.2 on Mac OS X 10.5.7.  I have Xcode
3.1.3 installed.

The error I got is below.

$ ./configure --prefix=/Users/me/python
checking for --with-universal-archs... 32-bit
checking MACHDEP... darwin
checking EXTRAPLATDIR... $(PLATMACDIRS)
checking machine type as reported by uname -m... i386
checking for --without-gcc... no
checking for gcc... gcc
checking for C compiler default output file name...
configure: error: C compiler cannot create executables
See `config.log' for more details.

Please send any ideas.


From rhodri at wildebst.demon.co.uk  Sun Jul 26 18:32:30 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Sun, 26 Jul 2009 23:32:30 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4hm7q$6g2$1@news.eternal-september.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<h4hkvn$ef6$1@panix3.panix.com>
	<h4hm7q$6g2$1@news.eternal-september.org>
Message-ID: <op.uxo4wgana8ncjz@gnudebst>

On Sun, 26 Jul 2009 14:31:06 +0100, Raffael Cavallaro  
<raffaelcavallaro at pas.espam.s.il.vous.plait.mac.com> wrote:

> On 2009-07-26 09:16:39 -0400, aahz at pythoncraft.com (Aahz) said:
>
>> There are plenty of expert C++
>> programmers who switched to Python;
>
> "plenty" is an absolute term, not a relative term. I sincerely doubt  
> that the majority of python users were formerly *expert* C++ programmers.

Nitpicking like this doesn't help your case.

>> your thesis only applies to the
>> legions of people who found it difficult to learn C++ in the first  
>> place.
>
> No, my thesis applies to the overwhelming majority of programmers who  
> found it more difficult to *master* (i.e., not merely use) C++ as  
> opposed to mastering python. BTW, this is a *complement* not a dis;  
> python is a better language than C++ precisely because it is more  
> sensibly and elegantly designed than C++ and therefore easier to master.

It is perhaps more accurate to say that Python was designed where C++
aggregated.  C was fundamentally the wrong place to have started from,
making C++ (as distinct from the subset of C++ that is really C) harder
to learn, never mind master, than it really needed to be.

> php represents the same process but farther down the ladder, as it were.  
> There's often a tradeoff between ease of mastery and power. python hits  
> a sweet spot for many tasks and many programmers, especially as compared  
> to C++ (or even lisp, which though more powerful than python is more  
> difficult to master. lisp beats C++ on both counts imho - more powerful  
> *and* easier to master). php hits a sweet spot only in a very restricted  
> domain. Beyond that, it is clearly inferior to python which has greater  
> power, but is more difficult to master.

Fundamentally incorrect.  PHP attracted many people because of where it
lives in the web application structure -- the part of the language that
was thought about very hard.  Beyond that there's nothing much to master,
so the whole ease vs power debate is rather pointless.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From bearophileHUGS at lycos.com  Sun Jul 26 18:42:22 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Sun, 26 Jul 2009 15:42:22 -0700 (PDT)
Subject: How to comment constant values?
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
Message-ID: <5c1b5c1e-7677-4786-a026-b4825568cf5b@j32g2000yqh.googlegroups.com>

Chris Rebert:
> Only modules, classes, and functions/methods can have docstrings
> associated with them.
> For anything else, you have to use comments; or you can mention them
> in the docstrings of related things.

What about adding docstrings to other Python things, especially to
variables?

Bye,
bearophile


From deets at nospam.web.de  Sun Jul 26 18:46:01 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 00:46:01 +0200
Subject: Error in compiling Python on OS X
In-Reply-To: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>
References: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>
Message-ID: <7d44lbF29p3p7U1@mid.uni-berlin.de>

Kevin schrieb:
> I am trying to compile Python 2.6.2 on Mac OS X 10.5.7.  I have Xcode
> 3.1.3 installed.
> 
> The error I got is below.
> 
> $ ./configure --prefix=/Users/me/python

Use a framework-build.

> checking for --with-universal-archs... 32-bit
> checking MACHDEP... darwin
> checking EXTRAPLATDIR... $(PLATMACDIRS)
> checking machine type as reported by uname -m... i386
> checking for --without-gcc... no
> checking for gcc... gcc
> checking for C compiler default output file name...
> configure: error: C compiler cannot create executables
> See `config.log' for more details.
> 
> Please send any ideas.

What happens if you write a simple test.c like this:


int main() {
    return 0;
}


and compile it with gcc on the commandline? There must be a file called 
"a.out" afterwards.

diez


From deets at nospam.web.de  Sun Jul 26 18:47:08 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 00:47:08 +0200
Subject: How to comment constant values?
In-Reply-To: <mailman.3750.1248645992.8015.python-list@python.org>
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
Message-ID: <7d44ndF29p3p7U2@mid.uni-berlin.de>

Chris Rebert schrieb:
> On Sun, Jul 26, 2009 at 2:49 PM, Erwin Mueller<devent at deventm.org> wrote:
>> Hello, I'm new to Python (using it for two months) and I wonder how can I
>> comment the const. values with the doc-strings. I.e. if I have code:
>>
>>> FRACTION_MIN = 1
>>> FRACTION_MAX = 10
>>>
>>> class Fraction(collections.MutableSequence):
>>>    '''Model a fraction with denominators.
>>>
>>>    It contains one ore more denomintors in a list for quick access.
>>>    The class is thread save, it uses a lock for all operations.
>>>    '''
>>>
>>>    def __init__(self):
>>>               # ...
>> The class and the methods can have doc-strings, but what about the const.
>> values, FRACTION_MIN and FRACTION_MAX?
> 
> Only modules, classes, and functions/methods can have docstrings
> associated with them.
> For anything else, you have to use comments; or you can mention them
> in the docstrings of related things.

While this is technically true, writing docstrings to constants (module 
or classlevel) works when one uses tools such as epydoc to generate 
documentation.

Diez


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 18:49:33 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 22:49:33 GMT
Subject: Globalize all variables in function without knowing names.
References: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>
	<mailman.3748.1248642820.8015.python-list@python.org>
	<5649dfb8-01a6-490d-bf30-b4a5206e644e@j21g2000yqe.googlegroups.com>
Message-ID: <027cce66$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 15:07:08 -0700, Tom wrote:

> Ah, thanks for that Dennis. I have a system already figured out where
> the user manually pre-enters all the variables into a .py file, which
> obviously isn't very efficient. The language isn't going to be used much
> except by me, so I suppose I'll just work with that until I look more
> into dictionaries, but I'm still beginning Python, and before that the
> only coding I did was a little bit of C++, so I'll wait up for that :P

Dictionaries are fundamental to Python and very useful. Not learning 
about them before starting to write code is like not learning about the 
accelerator pedal before starting to drive a car. You might be able to 
get somewhere by getting out and pushing, but it will be slow and 
exhausting.

Have you done the tutorial?

http://www.python.org/doc/current/tutorial/



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 18:49:47 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 22:49:47 GMT
Subject: Can't get UDP example to work
References: <148abf0f-c9e4-4156-8f16-e4e5615d350b@s6g2000vbp.googlegroups.com>
	<roy-51AEF5.12535926072009@news.panix.com>
	<2f578124-1ae3-45a5-a0c9-b8b05c0b5d3a@p23g2000vbl.googlegroups.com>
Message-ID: <027cce74$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 12:40:39 -0700, Paul Barry wrote:

> On Jul 26, 12:53?pm, Roy Smith <r... at panix.com> wrote:
>> In article
>> <148abf0f-c9e4-4156-8f16-e4e5615d3... at s6g2000vbp.googlegroups.com>,
>> ?Paul Barry <pauljbar... at gmail.com> wrote:
>>
>> > host = '127.0.0.1' ? ? ? ? ? # Bind to all interfaces
>>
>> This threw me off the track for a little while. ?The comment is wrong!
>> You're not binding to all interfaces, you're binding specifically to
>> the loopback interface. ?For what you're doing, it's fine, but the
>> comment is still wrong.
> 
> You are right.  The example in the book actually has
> 
> host = ''
> 
> So the comment is correct.  In trying to debug what was going on, I put
> 127.0.0.1 to see if that had something to do with it, which it didn't.

Now I have to quote Aahz's email sig:

"At Resolver we've found it useful to short-circuit any doubt and just 
refer to comments in code as 'lies'. "
--Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22


> But why not use
> 
>     print buf[0]
> 
> instead of
> 
>     sys.stdin.write(buf[0])
> 
> that much, I don't know.

print adds a trailing newline to the output, so the two lines aren't 
quite equivalent.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 18:58:34 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 22:58:34 GMT
Subject: Help understanding the decisions *behind* python? - immutable
	objects
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
Message-ID: <027cd083$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 11:24:48 -0700, John Nagle wrote:

>      An interesting issue is Python objects, which are always mutable.
> A "dict" of Python objects is allowed, but doesn't consider the contents
> of the objects, just their identity (address). Only built-in types are
> immutable; one cannot create a class of immutable objects.

Yes you can, for some definition of "can":

http://northernplanets.blogspot.com/2007/01/immutable-instances-in-python.html


Admittedly pure Python objects are only "cooperatively immutable". The 
immutability relies on the caller not going out of its way to break the 
instance, so you can mutate it if you work at it. One could, I suppose, 
try putting in complicated tricks to prevent that, but anything written 
in Python can ultimately be modified in Python.



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 19:20:58 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 23:20:58 GMT
Subject: How to comment constant values?
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
	<5c1b5c1e-7677-4786-a026-b4825568cf5b@j32g2000yqh.googlegroups.com>
Message-ID: <027cd5c2$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 15:42:22 -0700, Bearophile wrote:

> Chris Rebert:
>> Only modules, classes, and functions/methods can have docstrings
>> associated with them.
>> For anything else, you have to use comments; or you can mention them in
>> the docstrings of related things.
> 
> What about adding docstrings to other Python things, especially to
> variables?

Python doesn't have variables, it has objects bound to names. Because 
__doc__ is looked up on the class, not the instance, there's not much 
point in adding a docstring to the instance (even for instances which 
allow attributes to be added). And because names are internally stored as 
strings, you can't add a docstring to the name. So what you ask for is 
impossible.

But of course that could be changed, if there was consensus that what you 
ask for would be useful. But consider the consequences:

# A thought-experiment
>>> margin = 3  # allow a little bit of whitespace
>>> margin.__doc__ = "Extra space in pixels."
>>> help(x)
=> displays "Extra space in pixels."

So far so good. But now consider two equally unacceptable situations:

(1) If the docstring sticks to the object, then you get the docstring 
inappropriately showing up in places where it should:

>>> number_of_widgets = len( [a, b, c] )
>>> help(number_of_widgets)
=> displays "Extra space in pixels."


(2) If the docstring sticks to the name, then you get the docstring 
hanging around when you recycle the name to mean something else:

>>> margin = 15/100.0  # our profit margin is 15%
>>> help(margin)
=> displays "Extra space in pixels."

Now, in a large program, one shouldn't recycle names like that, but in a 
large program, you're unlikely to programmatically look up docstrings. 
Docstrings, and the help() function, are particularly useful in an 
interactive session, which is precisely the time that you're likely to 
recycle names.


In other words, it's currently impossible to bind docstrings to 
"variables" in Python, but even more fundamentally, the request is 
semantically incompatible with the Python name/object binding model.


-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 19:23:30 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 26 Jul 2009 23:23:30 GMT
Subject: How to comment constant values?
References: <200907270749.58845.devent@deventm.org>
	<mailman.3750.1248645992.8015.python-list@python.org>
	<7d44ndF29p3p7U2@mid.uni-berlin.de>
Message-ID: <027cd65b$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 00:47:08 +0200, Diez B. Roggisch wrote:

>> Only modules, classes, and functions/methods can have docstrings
>> associated with them.
>> For anything else, you have to use comments; or you can mention them in
>> the docstrings of related things.
> 
> While this is technically true, writing docstrings to constants (module
> or classlevel) works when one uses tools such as epydoc to generate
> documentation.

I've never used epydoc, so I'm not sure what you mean. Presumably it uses 
source code analysis to detect:

CONSTANT = 42
"""This is a constant."""

even though the string is ignored by the compiler.

Is that correct?



-- 
Steven


From andrew-newspost at areilly.bpc-users.org  Sun Jul 26 19:28:53 2009
From: andrew-newspost at areilly.bpc-users.org (Andrew Reilly)
Date: 26 Jul 2009 23:28:53 GMT
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<h4hkvn$ef6$1@panix3.panix.com>
	<h4hm7q$6g2$1@news.eternal-september.org>
Message-ID: <7d475kF29aga9U1@mid.individual.net>

On Sun, 26 Jul 2009 09:31:06 -0400, Raffael Cavallaro wrote:

> On 2009-07-26 09:16:39 -0400, aahz at pythoncraft.com (Aahz) said:
> 
>> There are plenty of expert C++
>> programmers who switched to Python;
> 
> "plenty" is an absolute term, not a relative term. I sincerely doubt
> that the majority of python users were formerly *expert* C++
> programmers.
> 
>> your thesis only applies to the
>> legions of people who found it difficult to learn C++ in the first
>> place.
> 
> No, my thesis applies to the overwhelming majority of programmers who
> found it more difficult to *master* (i.e., not merely use) C++ as
> opposed to mastering python. BTW, this is a *complement* not a dis;
> python is a better language than C++ precisely because it is more
> sensibly and elegantly designed than C++ and therefore easier to master.

Isn't it widely accepted that the number of people who have mastered C++ 
is about five?  All of the rest of us just struggle...

[I know enough of C++ to avoid it whenever I can, and to not use it for 
my own projects.  I'm happy with a mix of C, python and lisp(or scheme).]

-- 
Andrew


From pinkeen at gmail.com  Sun Jul 26 19:44:54 2009
From: pinkeen at gmail.com (Filip)
Date: Sun, 26 Jul 2009 16:44:54 -0700 (PDT)
Subject: python fast HTML data extraction library
References: <37da38d2-09a8-4fd2-94b4-5feae9675dcd@k1g2000yqf.googlegroups.com>
	<88e8ea19-7106-406a-a531-88c2b6893987@y7g2000yqa.googlegroups.com>
Message-ID: <0643e7ab-3136-4352-a849-a19882c3f9b2@c2g2000yqi.googlegroups.com>

On Jul 23, 3:53?am, Paul McGuire <pt... at austin.rr.com> wrote:
> # You should use raw string literals throughout, as in:
> # blah_re = re.compile(r'sljdflsflds')
> # (note the leading r before the string literal). ?raw string
> literals
> # really help keep your re expressions clean, so that you don't ever
> # have to double up any '\' characters.

Thanks, I didn't know about that, updated my code.

> # Attributes might be enclosed in single quotes, or not enclosed in
> any quotes at all.
> attr_re = re.compile('([\da-z]+?)\s*=\s*\"(.*?)\"', re.DOTALL |
> re.UNICODE | re.IGNORECASE)

Of course, you mean attribute's *value* can be enclosed in single/
double quotes?
To be true, I haven't seen single quote variant in HTML lately but I
checked it and it seems to be in the specs and it can be even quite
useful (man learns something every day).
Thank you for pointing that one out, I updated the code accordingly
(just realized that condition check REs need an update too :/).

As far as the lack of value quoting is concerned, I am not so sure I
need this - It would significanly obfuscate my REs and this practice
is rather deprecated, considered unsafe
and I've seen it only in very old websites.

> How would you extract data from a table? ?For instance, how would you
> extract the data entries from the table at this URL:http://tf.nist.gov/tf-cgi/servers.cgi? ?This would be a good example
> snippet for your module documentation.

This really seems like a nice example. I'll surely explain it in my
docs (examples are surely needed there ;)).

> Try extracting all of the <a href=...>sldjlsfjd</a> links from
> yahoo.com, and see how much of what you expect actually gets matched.

The library was used in my humble production environment, processing a
few hundred thousand+ of pages and spitting out about 10000 SQL
records so it does work quite good with a simple task like extracting
all links. However, I can't really say that the task introduced enough
diversity (there were only 9 different page templates) to say that the
library is 'tested'...

On Jul 26, 5:51 pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 23, 11:53 am, Paul McGuire <pt... at austin.rr.com> wrote:
>
> > On Jul 22, 5:43 pm, Filip <pink... at gmail.com> wrote:
>
> > # Needs re.IGNORECASE, and can have tag attributes, such as <BR
> > CLEAR="ALL">
> > line_break_re = re.compile('<br\/?>', re.UNICODE)
>
> Just in case somebody actually uses valid XHTML :-) it might be a good
> idea to allow for <br />
>
> > # what about HTML entities defined using hex syntax, such as &#xxxx;
> > amp_re = re.compile('\&(?![a-z]+?\;)', re.UNICODE | re.IGNORECASE)
>
> What about the decimal syntax ones? E.g. not only &nbsp; and &#xa0;
> but also &#160;
>
> Also, entity names can contain digits e.g. &sup1; &frac34;

Thanks for pointing this out, I fixed that. Although it has very
little impact on how the library performs its main task (I'd like to
see some comments on that ;)).


From aahz at pythoncraft.com  Sun Jul 26 19:56:59 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 16:56:59 -0700
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<mailman.3715.1248552511.8015.python-list@python.org>
	<2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>
Message-ID: <h4iqgb$ss5$1@panix3.panix.com>

In article <2a408da6-af57-45d0-a75f-4cbe384bb7f9 at s15g2000yqs.googlegroups.com>,
Michal Kwiatkowski  <constant.beta at gmail.com> wrote:
>On Jul 25, 10:00=A0pm, Jason Tackaberry <t... at urandom.ca> wrote:
>> On Sat, 2009-07-25 at 11:30 -0700, Michal Kwiatkowski wrote:
>>>
>>> Is there a way to tell if a generator has been exhausted using pure
>>> Python code? I've looked at CPython sources and it seems that
>>
>> Upon a cursory look, after a generator 'gen' is exhausted (meaning
>> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
>> None.
>
>Only in Python 2.5 or higher though. I need to support Python 2.3 and
>2.4 as well, sorry for not making that clear in the original post.

Are you sure?  It appears to work in Python 2.4; I don't have time to
check 2.3.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From tjreedy at udel.edu  Sun Jul 26 20:10:00 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Sun, 26 Jul 2009 20:10:00 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
Message-ID: <h4ir8n$eq$1@ger.gmane.org>

Michal Kwiatkowski wrote:

> The thing is I don't need the next item. I need to know if the
> generator has stopped without invoking it.

Write a one-ahead iterator class, which I have posted before, that sets 
.exhausted to True when next fails.

tjr



From nyamatongwe+thunder at gmail.com  Sun Jul 26 20:25:46 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Mon, 27 Jul 2009 00:25:46 GMT
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <mailman.3735.1248609191.8015.python-list@python.org>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>	<NQ_8m.6339$ze1.3567@news-server.bigpond.net.au>
	<mailman.3735.1248609191.8015.python-list@python.org>
Message-ID: <eu6bm.7529$ze1.5514@news-server.bigpond.net.au>

Mark Lawrence:

> If my sleuthing is correct the problem is with these lines
> 
> ilow *= self->itemSize;
> ihigh *= self->itemSize;
> 
> in GapBuffer_slice being computed before ilow and ihigh are compared to
> anything.

   This particular bug was because ihigh is the maximum 32 bit integer
2147483647 so multiplying it by the integer item size (4) caused
overflow. Adding an extra check fixes this:
    if (ihigh > self->lengthBody / self->itemSize)
        ihigh = self->lengthBody / self->itemSize;

   Committed a new version 1.02 and new downloads are available from
Google code.
http://code.google.com/p/gapbuffer/downloads/list

   Neil


From jackdied at gmail.com  Sun Jul 26 20:36:17 2009
From: jackdied at gmail.com (Jack Diederich)
Date: Sun, 26 Jul 2009 20:36:17 -0400
Subject: Mutable Strings - Any libraries that offer this?
In-Reply-To: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
References: <44e28fa9-af98-47da-a83b-5ec538b73d10@d9g2000prh.googlegroups.com>
Message-ID: <b8e622740907261736s3b340e42m83d65f1e292f7ebc@mail.gmail.com>

On Mon, Jul 20, 2009 at 5:57 AM, casebash<walkraft at gmail.com> wrote:
> Hi,
>
> I have searched this list and found out that Python doesn't have a
> mutable string class (it had an inefficient one, but this was removed
> in 3.0). Are there any libraries outside the core that offer this?

It depends on how mutable you want your strings.  There have been
several patches proposed on python-dev over the years that do things
like lazy concatenation and ropes.  They were always shot down because
the implementation or the semantics were very complicated.

-Jack


From tdelaney at avaya.com  Sun Jul 26 20:53:33 2009
From: tdelaney at avaya.com (Delaney, Timothy (Tim))
Date: Mon, 27 Jul 2009 08:53:33 +0800
Subject: missing 'xor' Boolean operator
In-Reply-To: <8d46fe89-9e91-45c7-9958-1b06e7f7b693@k19g2000yqn.googlegroups.com>
Message-ID: <E4C7BCAB1872014F81CEAACD25699B8C014E60E1@301081ANEX2.global.avaya.com>

Mark Dickinson wrote:

>> Since the 'and' and 'or' already return objects (and objects
>> evaluate to true or false), then 'xor' should behave likewise, IMO.
>> I expect that would be the case if it were ever added to the
>> language. 
> 
> I'm not so sure.  Did you ever wonder why the any() and all()
> functions introduced in 2.5 return a boolean rather than returning
> one of their arguments?  (I did, and I'm still not sure what the
> answer is.)

Consider the case of any() and all() operating on an empty iterable.
What type should they return?

It is impossible in the case of any() and all() to always return one of
the elements due to this edge case. Similarly, it is impossible in all
cases for a boolean xor to return one of the arguments - if both
arguments evaluate to a true (Something) value, xor must return a false
(Nothing) result.

Tim Delaney


From bearophileHUGS at lycos.com  Sun Jul 26 21:09:47 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Sun, 26 Jul 2009 18:09:47 -0700 (PDT)
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++ 
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org> 
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com> 
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
Message-ID: <b0afe5f7-0cd9-43af-ba1e-0e405d5ceb5f@h21g2000yqa.googlegroups.com>

William Dode':
> I updated the script (python, c and java) with your unrolled version
> + somes litle thinks.
[...]
> c 1.85s
> gcj 2.15s
> java 2.8s
> python2.5 + psyco 3.1s
> unladen-2009Q2 145s (2m45)
> python2.5 254s (4m14s)
> python3.1 300s (5m)
> ironpython1.1.1 680s (11m20)

Sorry for being late, I was away.

In your last C version this code is useless because the C compiler is
able to perform such simple optimization by itself (but probably
Python isn't able, so if you want the code to be the similar in all
versions it may be better to keep it):

shift_0=shift[0];
shift_1=shift[1];
shift_2=shift[2];
shift_3=shift[3];
shift_4=shift[4];
shift_5=shift[5];
shift_6=shift[6];
shift_7=shift[7];


This part in the Python code is useless:

shift_0 = shift[0]
shift_1 = shift[1]
shift_2 = shift[2]
shift_3 = shift[3]
shift_4 = shift[4]
shift_5 = shift[5]
shift_6 = shift[6]
shift_7 = shift[7]

Because later you copy values locally anyway:

def solve(nb, x, y,
        SIDE=SIDE, SQR_SIDE=SQR_SIDE, circuit=circuit,
        shift_0=shift_0,
        shift_1=shift_1,
        shift_2=shift_2,
        shift_3=shift_3,
        shift_4=shift_4,
        shift_5=shift_5,
        shift_6=shift_6,
        shift_7=shift_7,
        ):

So doing something like this is probably enough:

def solve(nb, x, y,
        SIDE=SIDE, SQR_SIDE=SQR_SIDE, circuit=circuit,
        shift_0=shift[0],
        shift_1=shift[1],
        shift_2=shift[2],
        shift_3=shift[3],
        shift_4=shift[4],
        shift_5=shift[5],
        shift_6=shift[6],
        shift_7=shift[7],
        ):

In low-level languages like C unrolling has to be done with care, to
avoid slowing down the code.

I have tried your latest C version using your compiler options, my
MinGW based on GCC 4.3.2 produces a crash at runtime. Using LLVM-GCC
it runs in 1.31 seconds. The D version is a bit less optimized than
your last C versions, yet using DMD it runs in 1.08-1.10 seconds.
Let's see if someone is able to write a C version faster than that D
code :-)

Have you have compiled/read my D version? In the D version you may
have missed that I did use an extra trick: unsigned integers, so it
needs just two tests to see if a number is in the 0-5, 0-5 square :-)
Note that Pyd, the Python-D bridge, may work with the latest DMD
version still (and it works if you use a bit older DMD compiler):
http://pyd.dsource.org/

Bye,
bearophile


From greg at cosc.canterbury.ac.nz  Sun Jul 26 21:12:26 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Mon, 27 Jul 2009 13:12:26 +1200
Subject: missing 'xor' Boolean operator
In-Reply-To: <mailman.3711.1248543076.8015.python-list@python.org>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<knclug.j10@spenarnc.xs4all.nl>
	<mailman.3711.1248543076.8015.python-list@python.org>
Message-ID: <7d4d6gF28qk7kU1@mid.individual.net>

Terry Reedy wrote:

> In Math and Python, a<b<c means a<b and b<c, not (a<b)<c or a<(b<c).
> != is a comparison operator like <,

Although Python extends the chaining principle to
!=, this is somewhat questionable, because
a < b and b < c implies a < c, but a != b and
b != c does not imply a != c.

I'm not sure I've ever seen a mathematician
write a != b != c, but if I did, I would tend
to think he meant to say that none of a, b,
c are equal to any other. That's not what it
means in Python, though.

-- 
Greg


From greg at cosc.canterbury.ac.nz  Sun Jul 26 21:30:41 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Mon, 27 Jul 2009 13:30:41 +1200
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
Message-ID: <7d4e8nF2a9i83U1@mid.individual.net>

Michal Kwiatkowski wrote:

> The first generator isn't finished, it yielded 1 and None. Second one
> is exhausted after yielding a single value (1). The problem is that,
> under Python 2.4 or 2.3 both invocations will generate the same trace
> output.

This seems to be a deficiency in the trace mechanism.
There really ought to be a 'yield' event to distinguish
yields from returns.

You could put in a feature request on python-dev
concerning this.

-- 
Greg


From aahz at pythoncraft.com  Sun Jul 26 22:44:24 2009
From: aahz at pythoncraft.com (Aahz)
Date: 26 Jul 2009 19:44:24 -0700
Subject: invoke method on many instances
References: <WRT7m.2863$P5.260@nwrddc02.gnilink.net>
	<mailman.3648.1248429993.8015.python-list@python.org>
	<h4htk2$fmb$1@panix3.panix.com>
	<mailman.3747.1248642434.8015.python-list@python.org>
Message-ID: <h4j4a8$ghf$1@panix3.panix.com>

In article <mailman.3747.1248642434.8015.python-list at python.org>,
Gabriel Genellina <gagsl-py2 at yahoo.com.ar> wrote:
>
>Ok, if you insist...
>
>NLMPI = Ni La M?s Puta Idea.
>IHNFI = I Have No Fucking Idea.

Thanks!
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From nidlobm at hotmail.com  Sun Jul 26 23:14:52 2009
From: nidlobm at hotmail.com (Michael Boldin)
Date: Sun, 26 Jul 2009 23:14:52 -0400
Subject: SEC doc parsing
Message-ID: <BLU134-W25E50A7805FABCBFD1985CA0140@phx.gbl>


I am looking for any parsing routines (written in python), for Security Exchange Commision (SEC) documents. These documents are on the SEC's EDGAR system  (at  ftp://ftp.sec.gov ) and I am especially interested in insider trading files known as Forms 3,4 and 5.

 

_________________________________________________________________
NEW mobile Hotmail. Optimized for YOUR phone.  Click here.
http://windowslive.com/Mobile?ocid=TXT_TAGLM_WL_CS_MB_new_hotmail_072009
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090726/56bb1768/attachment-0001.html>

From steve at REMOVE-THIS-cybersource.com.au  Sun Jul 26 23:18:53 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 27 Jul 2009 03:18:53 GMT
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
	<mailman.3752.1248653417.8015.python-list@python.org>
Message-ID: <027d0d84$0$5185$c3e8da3@news.astraweb.com>

On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:

> Michal Kwiatkowski wrote:
> 
>> The thing is I don't need the next item. I need to know if the
>> generator has stopped without invoking it.
> 
> Write a one-ahead iterator class, which I have posted before, that sets
> .exhausted to True when next fails.


And hope that the generator doesn't have side-effects...


-- 
Steven


From robert.kern at gmail.com  Mon Jul 27 00:11:12 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sun, 26 Jul 2009 23:11:12 -0500
Subject: PyQt GUI
In-Reply-To: <4ee78bf1-476d-4e41-b9da-c20297aad861@13g2000prl.googlegroups.com>
References: <bdd35fc4-7b34-4533-b6b3-79c1b29a1ca1@k13g2000prh.googlegroups.com>	<7bj5ulF22b4ktU1@mid.uni-berlin.de>	<mailman.2830.1247044998.8015.python-list@python.org>
	<60ff3276-0570-4222-9055-4e1a40538e61@r15g2000pra.googlegroups.com>
	<mailman.2864.1247095779.8015.python-list@python.org>	<5131c895-b155-486f-aff2-7587a114e60b@o18g2000pra.googlegroups.com>	<mailman.2902.1247154895.8015.python-list@python.org>	<88b09175-9167-4903-9524-2725a9ab9819@j9g2000prh.googlegroups.com>	<16422b45-a58b-451f-88d8-d85b70808d31@i4g2000prm.googlegroups.com>
	<mailman.3611.1248368602.8015.python-list@python.org>
	<4ee78bf1-476d-4e41-b9da-c20297aad861@13g2000prl.googlegroups.com>
Message-ID: <h4j9d1$p96$1@ger.gmane.org>

On 2009-07-26 07:04, Helvin wrote:

> C:\Qt\VTKbin7\Wrapping\Python>python setup.py install
> Traceback (most recent call last):
>    File "setup.py", line 138, in<module>
>      raise "ERROR: Must specify BUILD_TYPE=<config-name>  on command
> line."
> TypeError: exceptions must be classes or instances, not str
>
> Is it just a small error with input format or something?

Read the source, please:

# The build type ('Release', 'Debug' etc.).  If vtk_has_configuration_types
# is true this must be set.  It may be set on the command line by something
# like 'BUILD_TYPE=Release'.  For example::
#   python setup.py install --prefix=D:\\Python23 BUILD_TYPE=Release

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From robert.kern at gmail.com  Mon Jul 27 00:16:24 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Sun, 26 Jul 2009 23:16:24 -0500
Subject: How to comment constant values?
In-Reply-To: <027cd65b$0$5185$c3e8da3@news.astraweb.com>
References: <200907270749.58845.devent@deventm.org>	<mailman.3750.1248645992.8015.python-list@python.org>	<7d44ndF29p3p7U2@mid.uni-berlin.de>
	<027cd65b$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4j9mo$p96$2@ger.gmane.org>

On 2009-07-26 18:23, Steven D'Aprano wrote:
> On Mon, 27 Jul 2009 00:47:08 +0200, Diez B. Roggisch wrote:
>
>>> Only modules, classes, and functions/methods can have docstrings
>>> associated with them.
>>> For anything else, you have to use comments; or you can mention them in
>>> the docstrings of related things.
>> While this is technically true, writing docstrings to constants (module
>> or classlevel) works when one uses tools such as epydoc to generate
>> documentation.
>
> I've never used epydoc, so I'm not sure what you mean. Presumably it uses
> source code analysis to detect:
>
> CONSTANT = 42
> """This is a constant."""
>
> even though the string is ignored by the compiler.
>
> Is that correct?

epydoc 3 can actually parse the file to grab comments with a "#:" marker:

#: This is a constant.
CONSTANT = 42

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dpresley at midiowa.net  Mon Jul 27 00:20:51 2009
From: dpresley at midiowa.net (drednot57)
Date: Sun, 26 Jul 2009 21:20:51 -0700 (PDT)
Subject: len() should always return something
References: <mailman.3644.1248417347.8015.python-list@python.org>
Message-ID: <6ac8501e-b3ca-403b-8edb-c055b65bbff1@e11g2000yqo.googlegroups.com>

To the best of my recollection, the len() function only applies to
container objects; i. e. tuples, lists, strings, etc.  an integer
object is not a container, thus one receives an error when sending an
int as an argument for len().


From tjreedy at udel.edu  Mon Jul 27 02:02:19 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 27 Jul 2009 02:02:19 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <027d0d84$0$5185$c3e8da3@news.astraweb.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>	<877hxw4avj.fsf@benfinney.id.au>	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>	<mailman.3752.1248653417.8015.python-list@python.org>
	<027d0d84$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4jfta$6b1$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:
> 
>> Michal Kwiatkowski wrote:
>>
>>> The thing is I don't need the next item. I need to know if the
>>> generator has stopped without invoking it.
>> Write a one-ahead iterator class, which I have posted before, that sets
>> .exhausted to True when next fails.
> 
> 
> And hope that the generator doesn't have side-effects...

If run to exhastion, the same number of side-effects happen.
The only difference is that they each happen once step happpen sooner. 
For reading a file that is irrelevant. Much else, and the iterator is 
not just an iterator.

tjr




From tjreedy at udel.edu  Mon Jul 27 02:05:55 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 27 Jul 2009 02:05:55 -0400
Subject: missing 'xor' Boolean operator
In-Reply-To: <7d4d6gF28qk7kU1@mid.individual.net>
References: <mailman.3105.1247595911.8015.python-list@python.org>	<50697b2c0907141243p2f36db1fmefb276c21d95a8af@mail.gmail.com>	<h3j358$lhr$1@ger.gmane.org>	<mailman.3164.1247670958.8015.python-list@python.org>	<knclug.j10@spenarnc.xs4all.nl>	<mailman.3711.1248543076.8015.python-list@python.org>
	<7d4d6gF28qk7kU1@mid.individual.net>
Message-ID: <h4jg42$6b1$2@ger.gmane.org>

greg wrote:
> Terry Reedy wrote:
> 
>> In Math and Python, a<b<c means a<b and b<c, not (a<b)<c or a<(b<c).
>> != is a comparison operator like <,
> 
> Although Python extends the chaining principle to
> !=, this is somewhat questionable, because
> a < b and b < c implies a < c, but a != b and
> b != c does not imply a != c.
> 
> I'm not sure I've ever seen a mathematician
> write a != b != c, but if I did, I would tend
> to think he meant to say that none of a, b,
> c are equal to any other. That's not what it
> means in Python, though.

However, == is transitive, and a == b == c is quite common.
It would hardly do to have different rules for !=.

Either we have a uniform rule for a compare_op b compare_ob c, as we do, 
or we have several fussy rules that would be hard to remember.



From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 27 02:22:54 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 27 Jul 2009 06:22:54 GMT
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
	<mailman.3752.1248653417.8015.python-list@python.org>
	<027d0d84$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3757.1248674553.8015.python-list@python.org>
Message-ID: <027d38a5$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 02:02:19 -0400, Terry Reedy wrote:

> Steven D'Aprano wrote:
>> On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:
>> 
>>> Michal Kwiatkowski wrote:
>>>
>>>> The thing is I don't need the next item. I need to know if the
>>>> generator has stopped without invoking it.
>>> Write a one-ahead iterator class, which I have posted before, that
>>> sets .exhausted to True when next fails.
>> 
>> 
>> And hope that the generator doesn't have side-effects...
> 
> If run to exhastion, the same number of side-effects happen. The only
> difference is that they each happen once step happpen sooner. For
> reading a file that is irrelevant. Much else, and the iterator is not
> just an iterator.

I believe the OP specifically said he needs to detect whether or not an 
iterator is exhausted, without running it to exhaustion, so you shouldn't 
assume that the generator has been exhausted.

When it comes to side-effects, timing matters. For example, a generator 
which cleans up after it has run (deleting temporary files, closing 
sockets, etc.) will leave the environment in a different state if run to 
exhaustion than just before exhaustion. Even if you store the final 
result in a one-ahead class, you haven't saved the environment, and that 
may be significant.

(Of course, it's possible that it isn't significant. Not all differences 
make a difference.)

The best advice is, try to avoid side-effects, especially in generators.


-- 
Steven


From jayshree06comp at gmail.com  Mon Jul 27 02:47:00 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Sun, 26 Jul 2009 23:47:00 -0700 (PDT)
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
	<b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>
	<m2ocrbk1k2.fsf@cs.uu.nl>
Message-ID: <e004759b-4fd5-49b4-b3a6-1e2063a9aed9@v36g2000yqv.googlegroups.com>

On Jul 23, 5:48?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> jayshree <jayshree06c... at gmail.com> (j) wrote:
> >j> On Jul 21, 8:59?pm, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>> The recipient_public_key.pem file is the public key of the recipient
> >>> which means the person that is going to receive the encrypted message.
> >>> You should get it from the recipient him/herself or from some key store
> >>> where s/he has deposited it.
>
> [...]
>
> >j> error coming like - IOError: [Errno 2] No such file or directory:
> >j> 'recipient_public_key.pem'
> >j> Is this not the inbuilt file.
> >j> How should i create such type of file.
>
> You don't create it. See above. If you understand what is is you know
> why it can't be builtin. If you don't understand it is better if you
> first learn about OpenSSL, otherwise you run the risk to make serious
> errors.
>
> If you are just experimenting to create a message for yourself then you
> have to create the public key because you are then the recipient
> yourself. That has been answered onhttp://stackoverflow.com/questions/1169798/m2crypto-package
> --
> Piet van Oostrum <p... at cs.uu.nl>
> URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4]
> Private email: p... at vanoostrum.org

import M2Crypto
from M2Crypto import RSA,SSL
def encrypt():
    pk = open('my_key.public.pem', 'rb').read()
    rsa = M2Crypto.RSA.load_pub_key(pk) #return a M2Crypto.RSA.RSA_pub
object.
    plaintext = 4545479545655576767767686688782344
    msg = rsa.public_encrypt(plaintext,RSA.pkcs1_padding)
    print msg;
    encrypt()

This is code i am refering.
The Problem is coming with .pem file.
I also asked this questions at  http://stackoverflow.com/questions/1176864/problem-with-the-pem-file-closed
which has not been answered .
please help me out....

thanks


From nagle at animats.com  Mon Jul 27 03:06:36 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 00:06:36 -0700
Subject: Help understanding the decisions *behind* python? - immutable
	objects
In-Reply-To: <027cd083$0$5185$c3e8da3@news.astraweb.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>	<mailman.3511.1248244497.8015.python-list@python.org>	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
	<027cd083$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4a6d514d$0$1641$742ec2ed@news.sonic.net>

Steven D'Aprano wrote:
> On Sun, 26 Jul 2009 11:24:48 -0700, John Nagle wrote:
> 
>>      An interesting issue is Python objects, which are always mutable.
>> A "dict" of Python objects is allowed, but doesn't consider the contents
>> of the objects, just their identity (address). Only built-in types are
>> immutable; one cannot create a class of immutable objects.
> 
> Yes you can, for some definition of "can":
> 
> http://northernplanets.blogspot.com/2007/01/immutable-instances-in-python.html
> 
> 
> Admittedly pure Python objects are only "cooperatively immutable". 

    Right.  I've been thinking about this as a way of improving
concurrency handling.  The general idea is that objects shared
across threads would have to be either be immutable or synchronized.
Regular objects would be limited to a single thread.  It's a path
to multithread programs without a global lock.  Needs more work
to become a serious proposal.  (It may not be worth the trouble;
a few years ago we were hearing about how 64-core CPUs were going
to become mainstream, but instead, the industry is going in the
direction of the same compute power for less money and with
less power consumption.)

				John Nagle


From abhigyan_agrawal at in.ibm.com  Mon Jul 27 03:11:42 2009
From: abhigyan_agrawal at in.ibm.com (abhi)
Date: Mon, 27 Jul 2009 00:11:42 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
Message-ID: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>

Hi,
    I am facing a problem using PyArg_ParseTuple() in my C-API
extension. Here is a small repro of the function:

static PyObject *parsetuple_test(PyObject *self, PyObject *args)
{
	SQLUSMALLINT param_no = 0;
	PyObject *py_obj = NULL;

	if (!PyArg_ParseTuple(args, "Oi", &py_obj, &param_no)){

		return NULL;
	}
	printf("%d\n", param_no);
	return NULL;
}

This function works fine and prints the correct value passed
(param_no) when I test it on Linux or Windows. However, it always
prints 0 (initial value defined in function) when I run it on AIX.

I think the problem is with "Oi" argument, if I replace that with "OO"
and specifically convert it integer/sqlsmallint. It works fine on AIX,
but I want to use "i" and not "O".

Any ideas on what is the reason behind the problem and how to fix
this?

Thanks,
Abhigyan


From jayshree06comp at gmail.com  Mon Jul 27 03:28:50 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Mon, 27 Jul 2009 00:28:50 -0700 (PDT)
Subject: open a file in python
Message-ID: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>

pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()

Please tell me how to open a file placed in any directory or in same
directory.

After opening this file i want to use the contain (public key ) for
encryption





thanks


From metallourlante at gmail.com  Mon Jul 27 03:40:09 2009
From: metallourlante at gmail.com (Alex)
Date: Mon, 27 Jul 2009 00:40:09 -0700 (PDT)
Subject: web page retrieve problems
References: <16343e3d-1be4-422b-8bff-c07fa4aa4c54@j9g2000prh.googlegroups.com>
Message-ID: <7dd16ce7-8442-4e67-a949-442b287e00dd@j21g2000yqe.googlegroups.com>

On Jul 26, 8:57?am, golu <bhardwajjaye... at gmail.com> wrote:
> the following function retrieves pages from the web and saves them in
> a specified dir. i want to extract the respective filenames from the
> urls e.g the page code.google.com shud be saved as code-google.htm ?or
> something similar. can u suggest me a way to do it

Try with urllib.urlretrieve from standard lib:

urllib.urlretrieve(url[, filename[, reporthook[, data]]])?
Copy a network object denoted by a URL to a local file, if necessary.
If the URL points to a local file, or a valid cached copy of the
object exists, the object is not copied. Return a tuple (filename,
headers) where filename is the local file name under which the object
can be found, and headers is whatever the info() method of the object
returned by urlopen() returned (for a remote object, possibly cached).
Exceptions are the same as for urlopen().


From kushal.kumaran+python at gmail.com  Mon Jul 27 04:09:26 2009
From: kushal.kumaran+python at gmail.com (Kushal Kumaran)
Date: Mon, 27 Jul 2009 13:39:26 +0530
Subject: open a file in python
In-Reply-To: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
Message-ID: <1e364c4e0907270109u2aa8e702oa3ebaaab065f5e90@mail.gmail.com>

On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06comp at gmail.com> wrote:
> pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>
> Please tell me how to open a file placed in any directory or in same
> directory.
>
> After opening this file i want to use the contain (public key ) for
> encryption
>

Does the code you've put into your message not read that file?  If you
get an exception, copy-paste in the traceback message you get into
your mail.

-- 
kushal


From piet at cs.uu.nl  Mon Jul 27 04:18:20 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 10:18:20 +0200
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org>
Message-ID: <m21vo2czeb.fsf@cs.uu.nl>

>>>>> Dotan Cohen <dotancohen at gmail.com> (DC) wrote:

>DC> Referring to this article:
>DC> http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/

>DC> The author, who is specifically looking for math-related functions, writes:
>DC> """
>DC> The dream algorithm R&D tool would be similar to Matlab or Mathematica
>DC> but could be compiled to fast, efficient binaries similar to ANSI C
>DC> and would be available for all platforms. An integrated GUI builder
>DC> similar to Visual Basic and integrated network support would be
>DC> helpful.
>DC> """

>DC> It looks to me like he is looking for Python.

No fast, efficient binaries yet, and no integrated GUI builder.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From vesa.koppa at gmail.com  Mon Jul 27 04:51:51 2009
From: vesa.koppa at gmail.com (=?ISO-8859-1?Q?Vesa_K=F6pp=E4?=)
Date: Mon, 27 Jul 2009 11:51:51 +0300
Subject: How do I generate dia diagrams from python source code?
In-Reply-To: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
References: <8d6fc359-7a02-4978-a9d3-93a1271a50db@e27g2000yqm.googlegroups.com>
Message-ID: <4a6d6aa6$0$24756$4f793bc4@news.tdc.fi>

Qauzzix wrote:
> Greetings.
> 
> Since I have been using dia to make my UML diagrams. I also found an
> util named dia2code that generates python code from dia diagram. Now
> that I have that option I really want to find a way to generate dia
> diagram from existing code and/or maintain my diagrams.
> 
> I have been googling  like crazy trying to find a way but with no
> luck. Anyone here know how to do this?
> 
> Peace,
>  - Jakob Sv. Bjarnason

Hi.

There is this utility called autodia.
http://www.aarontrevena.co.uk/opensource/autodia/
I think it does what you want. It is written in perl.
It can read several languages and outputs dia diagrams.

BTW, I found it by going to dia2code homepage and then to
its links page. It is listed in there.

-- 
Vesa


From s.selvamsiva at gmail.com  Mon Jul 27 04:53:33 2009
From: s.selvamsiva at gmail.com (S.Selvam)
Date: Mon, 27 Jul 2009 14:23:33 +0530
Subject: Itext for Python
In-Reply-To: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com>
References: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com>
Message-ID: <b423b9550907270153v5b21cb35wc3741c8d5775e574@mail.gmail.com>

On Sun, Jul 26, 2009 at 11:52 PM, Santhosh Kumar
<santhosh.vkumar at gmail.com>wrote:

> Hi all,           One of my cousin  suggested me to do a IText
> PDF converter for python. Actually I heard that there is
> no separate IText converter either we have to go for jython or GCJ with
> wrapper. Instead of wrapping, my plan is to create a separate module with
> Python and I am thinking of doing this in as my final year project also.
> Kindly give me your suggestion.
>


As for as i know, no pure python module exists for iText PDF generator,
where iText seems to be a standard one for PDF related works.There are some
other modules for pdf work but might not be as standard as iText.Surely some
senior programmers  will suggest you better way to proceed further.


>         With anticipation,
>
> SanthoshVKumar.
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>


-- 
Yours,
S.Selvam
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090727/bcaf8383/attachment-0001.html>

From Tom.sully at gmx.com  Mon Jul 27 04:58:48 2009
From: Tom.sully at gmx.com (Tom)
Date: Mon, 27 Jul 2009 01:58:48 -0700 (PDT)
Subject: Globalize all variables in function without knowing names.
References: <b4cddda0-846e-4961-83e7-5d2c8d3ea85e@v36g2000yqv.googlegroups.com>
	<mailman.3748.1248642820.8015.python-list@python.org>
	<5649dfb8-01a6-490d-bf30-b4a5206e644e@j21g2000yqe.googlegroups.com>
	<027cce66$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <50a401f0-b203-4dcd-baa9-22895a068f3b@r27g2000vbn.googlegroups.com>

> Dictionaries are fundamental to Python and very useful. Not learning
> about them before starting to write code is like not learning about the
> accelerator pedal before starting to drive a car.

Heh, I just looked at the actual tutorial for Dictionaries and I have
to say they are very useful. Basically just arrays with strings(or any
other data type, except lists) instead of numbers. I'll work on trying
to integrate them into my language code as, like you said, user
data... Then when a user requests a variable it just accessess the
dictionary, that should work. Thanks!
This is easier than I thought.

> Have you done the tutorial?

I did the first few sections, and then flipped back to it later on to
find out what I needed to know as I coded applications. A bad idea, in
retrospect, particilary as it slowed down my coding time alot.


From hendrik at microcorp.co.za  Mon Jul 27 05:05:06 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Mon, 27 Jul 2009 11:05:06 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
Message-ID: <200907271105.06692.hendrik@microcorp.co.za>

On Sunday 26 July 2009 21:26:46 David Robinow wrote:

>
>  I'm a mediocre programmer. Does this mean I should switch to PHP?

I have searched, but I can find nothing about this mediocre language.

Could you tell us more?

- Hendrik


From dickinsm at gmail.com  Mon Jul 27 05:12:16 2009
From: dickinsm at gmail.com (Mark Dickinson)
Date: Mon, 27 Jul 2009 02:12:16 -0700 (PDT)
Subject: missing 'xor' Boolean operator
References: <mailman.3754.1248656735.8015.python-list@python.org>
Message-ID: <668280c4-6c52-4c2e-ab6f-9b3701399134@s15g2000yqs.googlegroups.com>

On Jul 27, 1:53?am, "Delaney, Timothy (Tim)" <tdela... at avaya.com>
wrote:
> Mark Dickinson wrote:
> >> Since the 'and' and 'or' already return objects (and objects
> >> evaluate to true or false), then 'xor' should behave likewise, IMO.
> >> I expect that would be the case if it were ever added to the
> >> language.
>
> > I'm not so sure. ?Did you ever wonder why the any() and all()
> > functions introduced in 2.5 return a boolean rather than returning
> > one of their arguments? ?(I did, and I'm still not sure what the
> > answer is.)
>
> Consider the case of any() and all() operating on an empty iterable.
> What type should they return?
>
> It is impossible in the case of any() and all() to always return one of
> the elements due to this edge case.

Yes, of course; the alternative implementation I was thinking of
was the one that I implemented eons ago for my own pre-2.5 code,
where I defined any and all roughly as:

any([x1, x2, x3, ...]) <-> False or x1 or x2 or x3 or ...
all([x1, x2, x3, ...]) <-> True and x1 and x2 and x3 and ...

At the time this seemed like the obvious choice, so I was a bit
surprised when it was chosen to always return a bool instead in
the official versions.

Now that I'm older and wise^H^H^H^H, well, maybe just older, the
pure bool version seems cleaner and less error-prone, even if
it's mildly inconsistent with the behaviour of and and or.

Mark


From sjmachin at lexicon.net  Mon Jul 27 05:25:19 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 27 Jul 2009 02:25:19 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
References: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>
Message-ID: <635a7311-62e1-4da5-98ad-b62cfa150287@k30g2000yqf.googlegroups.com>

On Jul 27, 5:11?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
> Hi,
> ? ? I am facing a problem using PyArg_ParseTuple() in my C-API
> extension. Here is a small repro of the function:
>
> static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> {
> ? ? ? ? SQLUSMALLINT param_no = 0;

Sorry, my crystal ball is on the fritz. What is SQLUSMALLINT on
Windows/Linux/AIX?
What does
    printf("%d %d %d\n", sizeof(SQLUSMALLINT), sizeof(int), sizeof
(long));
give you on each platform?

> ? ? ? ? PyObject *py_obj = NULL;
>
> ? ? ? ? if (!PyArg_ParseTuple(args, "Oi", &py_obj, &param_no)){
>
> ? ? ? ? ? ? ? ? return NULL;
> ? ? ? ? }
> ? ? ? ? printf("%d\n", param_no);
> ? ? ? ? return NULL;
>
> }
>
> This function works fine and prints the correct value passed
> (param_no) when I test it on Linux or Windows. However, it always
> prints 0 (initial value defined in function) when I run it on AIX.

Consider that 0 could have been plucked out of the air and has nothing
to do with the initial value of param_no. Try initialising it to
something distinctive, like 0xfedcba98. Use %08x format in the printf
rather than %d.


>
> I think the problem is with "Oi" argument, if I replace that with "OO"
> and specifically convert it integer/sqlsmallint. It works fine on AIX,
> but I want to use "i" and not "O".
>
> Any ideas on what is the reason behind the problem and how to fix
> this?

I jump-started the crystal ball from the over-head tram wire and saw
this: """SQLSMALLINT is 16 bits on all platforms, int/long is 32 bits
on all platforms, first 2 are little-endian, AIX is bigendian, the "i"
format expects SIGNED int /long, so param_no is getting (win:x,
linux:x, aix:0) and the next 16 bits in memory are getting trashed
with (win:0, linux:0, aix:x) (when x is your input smallish integer)
and luckily this trashing didn't cause a crash. You can receive the
result from the function in an int/long then have code to reject it if
it won't fit into a SQLUSMALLINT, and cast it otherwise. If you don't
care about overflow (NOT recommended), just use "H" format instead if
"i" format"""

Could be wrong, really shouldn't subject precision instruments to 415V
DC, only OPs :-)

N.B. to detect endianness : use print sys.byteorder

HTH,
John


From jayshree06comp at gmail.com  Mon Jul 27 05:37:47 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Mon, 27 Jul 2009 02:37:47 -0700 (PDT)
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
Message-ID: <cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>

On Jul 27, 1:09?pm, Kushal Kumaran <kushal.kumaran+pyt... at gmail.com>
wrote:
> On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06c... at gmail.com> wrote:
> > pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>
> > Please tell me how to open a file placed in any directory or in same
> > directory.
>
> > After opening this file i want to use the contain (public key ) for
> > encryption
>
> Does the code you've put into your message not read that file? ?If you
> get an exception, copy-paste in the traceback message you get into
> your mail.
>
> --
> kushal


    try:
        pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
    except IOError:
        print "Error: can\'t find file or read data"
    else:
        print "reading from file successfully"

>Still no error it gives .what to do?


From m_tayseer82 at yahoo.com  Mon Jul 27 05:39:30 2009
From: m_tayseer82 at yahoo.com (Mohammad Tayseer)
Date: Mon, 27 Jul 2009 02:39:30 -0700 (PDT)
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <m21vo2czeb.fsf@cs.uu.nl>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
Message-ID: <468250.83203.qm@web31106.mail.mud.yahoo.com>

You can generate binaries using py2exe, and you can create UI using Tkinter (which is very easy) or wxPython (which have GUI builders)

 Mohammad Tayseer
http://spellcoder.com/blogs/tayseer





________________________________
From: Piet van Oostrum <piet at cs.uu.nl>
To: python-list at python.org
Sent: Monday, July 27, 2009 11:18:20 AM
Subject: Re: Looking for a dream language: sounds like Python to me.

>>>>> Dotan Cohen <dotancohen at gmail.com> (DC) wrote:

>DC> Referring to this article:
>DC> http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/

>DC> The author, who is specifically looking for math-related functions, writes:
>DC> """
>DC> The dream algorithm R&D tool would be similar to Matlab or Mathematica
>DC> but could be compiled to fast, efficient binaries similar to ANSI C
>DC> and would be available for all platforms. An integrated GUI builder
>DC> similar to Visual Basic and integrated network support would be
>DC> helpful.
>DC> """

>DC> It looks to me like he is looking for Python.

No fast, efficient binaries yet, and no integrated GUI builder.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org
-- 
http://mail.python.org/mailman/listinfo/python-list



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090727/2839d885/attachment-0001.html>

From deets at nospam.web.de  Mon Jul 27 05:55:02 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 11:55:02 +0200
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
	<cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>
Message-ID: <7d5brmF2a1alcU1@mid.uni-berlin.de>

jayshree wrote:

> On Jul 27, 1:09?pm, Kushal Kumaran <kushal.kumaran+pyt... at gmail.com>
> wrote:
>> On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06c... at gmail.com>
>> wrote:
>> > pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>>
>> > Please tell me how to open a file placed in any directory or in same
>> > directory.
>>
>> > After opening this file i want to use the contain (public key ) for
>> > encryption
>>
>> Does the code you've put into your message not read that file? ?If you
>> get an exception, copy-paste in the traceback message you get into
>> your mail.
>>
>> --
>> kushal
> 
> 
>     try:
>         pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>     except IOError:
>         print "Error: can\'t find file or read data"
>     else:
>         print "reading from file successfully"
> 
>>Still no error it gives .what to do?

Erm - so it doesn't give an error - which means you have successfully opened
a file, and read it's contents.

So what exactly is your problem?

Diez


From nogetfx at gmail.com  Mon Jul 27 06:18:55 2009
From: nogetfx at gmail.com (Lars)
Date: Mon, 27 Jul 2009 03:18:55 -0700 (PDT)
Subject: Call function from another class
Message-ID: <4b6b0e4b-b85b-43cf-a695-e3a722de01cc@e11g2000yqo.googlegroups.com>

Hi
I'm trying to make an simple image viewer in wxPython and rotate an
image with a slider. The code at Pastebin is striped down at bit. The
class Frame(wx.Frame) is the main window, the function "def
CreateMenuBar" (l. 39) creates a menu, where the function "def onRotate
(self,event):" (l. 43) is called. The slider appear in at 2nd window,
class rotationSlider(wx.Frame).
My problem is what to do, when the Okay button is pressed in the
"rotationSlider" frame. How to get the slider value to my main window
and how to call a function to do the rotation. I tried something with
a global variable, but it would make no difference regarding the
function problem. Amongst the other things I've tried is to bind the
event of the 2nd/slider window closing (l. 46), but no.
Python code at Pastebin: http://pastebin.com/m7c24ec34

So some help on Classes and etc., would be appreciated.

/Lars


From himanshu.garg at gmail.com  Mon Jul 27 06:38:04 2009
From: himanshu.garg at gmail.com (++imanshu)
Date: Mon, 27 Jul 2009 03:38:04 -0700 (PDT)
Subject: _msi.Record object has no attribute 'GetString'
Message-ID: <32e0b242-8635-40b5-a366-2c9967e64e1c@d4g2000yqa.googlegroups.com>

The documentation (http://docs.python.org/library/msilib.html#record-
objects) for msilib mentions the GetString() method on Record objects.
However, the following snippet :-

db = msilib.OpenDatabase(os.path.join(root, file),
msilib.MSIDBOPEN_READONLY)
view = db.OpenView('SELECT * FROM Property')
view.Execute(None)
r = view.Fetch()
print dir(r)
print r.GetString(0)

gives me this error :-

c:\>python msi.py
['ClearData', 'GetFieldCount', 'SetInteger', 'SetStream', 'SetString',
__class__', '__delattr__', '__doc__', '__getattribute__', '__hash__',
'__init__', '__new__', __reduce__', '__reduce_ex__', '__repr__',
'__setattr__', '__str__']
Traceback (most recent call last):
  File "msi.py", line 18, in <module>
    print r.GetString(0)
AttributeError: '_msi.Record' object has no attribute 'GetString'

Am I missing something?

Thank You,
Himanshu


From deets at nospam.web.de  Mon Jul 27 06:43:14 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 12:43:14 +0200
Subject: Call function from another class
References: <4b6b0e4b-b85b-43cf-a695-e3a722de01cc@e11g2000yqo.googlegroups.com>
Message-ID: <7d5em2F2anm94U1@mid.uni-berlin.de>

Lars wrote:

> Hi
> I'm trying to make an simple image viewer in wxPython and rotate an
> image with a slider. The code at Pastebin is striped down at bit. The
> class Frame(wx.Frame) is the main window, the function "def
> CreateMenuBar" (l. 39) creates a menu, where the function "def onRotate
> (self,event):" (l. 43) is called. The slider appear in at 2nd window,
> class rotationSlider(wx.Frame).
> My problem is what to do, when the Okay button is pressed in the
> "rotationSlider" frame. How to get the slider value to my main window
> and how to call a function to do the rotation. I tried something with
> a global variable, but it would make no difference regarding the
> function problem. Amongst the other things I've tried is to bind the
> event of the 2nd/slider window closing (l. 46), but no.
> Python code at Pastebin: http://pastebin.com/m7c24ec34
> 
> So some help on Classes and etc., would be appreciated.

If I'm not mistaken, in "doRotate" you should be able to refer to the
to-be-closed dialog via

self.frameRotate

Now if you change the "sliderUpdate"-code to store that angle instead of
just letting it fall out of scope, you could access that value through
frameRotate:

def sliderUpdate(self, event):
        angle=self.slider.GetValue()
        ROTATION_ANGLE=angle
        self.angle = angle 
        self.Destroy()



def doRotate(self,event):
    """Rotating image"""
    print self.frameRotate.angle


Diez
 


From abhigyan_agrawal at in.ibm.com  Mon Jul 27 06:49:04 2009
From: abhigyan_agrawal at in.ibm.com (abhi)
Date: Mon, 27 Jul 2009 03:49:04 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
References: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>
	<635a7311-62e1-4da5-98ad-b62cfa150287@k30g2000yqf.googlegroups.com>
Message-ID: <43b1acda-b518-40ef-acde-145e28379775@r25g2000vbn.googlegroups.com>

On Jul 27, 2:25?pm, John Machin <sjmac... at lexicon.net> wrote:
> On Jul 27, 5:11?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
>
> > Hi,
> > ? ? I am facing a problem using PyArg_ParseTuple() in my C-API
> > extension. Here is a small repro of the function:
>
> > static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> > {
> > ? ? ? ? SQLUSMALLINT param_no = 0;
>
> Sorry, my crystal ball is on the fritz. What is SQLUSMALLINT on
> Windows/Linux/AIX?
> What does
> ? ? printf("%d %d %d\n", sizeof(SQLUSMALLINT), sizeof(int), sizeof
> (long));
> give you on each platform?
>
> > ? ? ? ? PyObject *py_obj = NULL;
>
> > ? ? ? ? if (!PyArg_ParseTuple(args, "Oi", &py_obj, &param_no)){
>
> > ? ? ? ? ? ? ? ? return NULL;
> > ? ? ? ? }
> > ? ? ? ? printf("%d\n", param_no);
> > ? ? ? ? return NULL;
>
> > }
>
> > This function works fine and prints the correct value passed
> > (param_no) when I test it on Linux or Windows. However, it always
> > prints 0 (initial value defined in function) when I run it on AIX.
>
> Consider that 0 could have been plucked out of the air and has nothing
> to do with the initial value of param_no. Try initialising it to
> something distinctive, like 0xfedcba98. Use %08x format in the printf
> rather than %d.
>
>
>
> > I think the problem is with "Oi" argument, if I replace that with "OO"
> > and specifically convert it integer/sqlsmallint. It works fine on AIX,
> > but I want to use "i" and not "O".
>
> > Any ideas on what is the reason behind the problem and how to fix
> > this?
>
> I jump-started the crystal ball from the over-head tram wire and saw
> this: """SQLSMALLINT is 16 bits on all platforms, int/long is 32 bits
> on all platforms, first 2 are little-endian, AIX is bigendian, the "i"
> format expects SIGNED int /long, so param_no is getting (win:x,
> linux:x, aix:0) and the next 16 bits in memory are getting trashed
> with (win:0, linux:0, aix:x) (when x is your input smallish integer)
> and luckily this trashing didn't cause a crash. You can receive the
> result from the function in an int/long then have code to reject it if
> it won't fit into a SQLUSMALLINT, and cast it otherwise. If you don't
> care about overflow (NOT recommended), just use "H" format instead if
> "i" format"""
>
> Could be wrong, really shouldn't subject precision instruments to 415V
> DC, only OPs :-)
>
> N.B. to detect endianness : use print sys.byteorder
>
> HTH,
> John

Hi,
    Thanks for the response. If I don't use SQLUSMALLINT and use int
instead, then also I see the same problem.
static PyObject *parsetuple_test(PyObject *self, PyObject *args)
 {
        int param_no = 0;
....
....
}
This also prints out 0 for AIX and actual value passed in other
platforms. If I initialize param_no with some other value (e.g. 90),
it prints out that value.

-
Abhigyan


From piet at cs.uu.nl  Mon Jul 27 07:08:27 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 13:08:27 +0200
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com>
Message-ID: <m2skgibcyc.fsf@cs.uu.nl>

>>>>> Paul Rubin <http://phr.cx at NOSPAM.invalid> (PR) wrote:

>PR> Rob Knop <rknop at pobox.com> writes:
>>> Are there any python libraries that will take a public key in this
>>> format and do RSA encoding on it?

>PR> Try www.trevp.com/tlslite

I have looked into tlslite and found no easy way to do this. Maybe I
overlooked it. On the other hand with M2Crypto it isn't that hard.

However, M2Crypto wants to load keys in PEM format rather than the DER
format that the Java getEncoded() produces. It is not hard to convert
this to PEM format: just Base64 encode it and put a header and trailer
line around it. The conversion can be done with openssl or just on the
fly in the Python code.
Please note that the text to be encrypted must be smaller than the key
size (at least 11 bytes smaller). You shouldn't encrypt large data with
RSA anyway: it is too slow. Normally you would encrypt a session key
with RSA and encrypt the data with the session key using a symmetric
algorithms like AES.

Here is an example script:
If your OS doesn't have /dev/urandom you should probably seed OpenSSL's
PRNG to be more secure.
------------------------------------------------------------------------
from M2Crypto import BIO, RSA

pubkey = open("pubkey.der", 'rb').read()

import base64
pubkey = base64.encodestring(pubkey)
pubkey = '-----BEGIN PUBLIC KEY-----\n' + pubkey + '-----END PUBLIC KEY-----'

bio = BIO.MemoryBuffer(pubkey)
rsa = RSA.load_pub_key_bio(bio)

plaintext = "This is my secret text."

codetext = rsa.public_encrypt(plaintext, RSA.pkcs1_padding)

with open("codetext", 'wb') as out:
    out.write(codetext)
------------------------------------------------------------------------
The following Java program decodes this with the corresponding private
key:
------------------------------------------------------------------------
import java.security.*;
import javax.crypto.*;
import java.security.spec.*;
import java.security.interfaces.*;
import java.io.*;

class Decrypt {

    public static void main(String[] args) {      

        byte[] key = null;
        try {
            File file = new File("privkey.der");
            FileInputStream keyfile = new FileInputStream(file);
            key = new byte[(int)file.length()];
            DataInputStream dis= new DataInputStream(keyfile);
            dis.readFully(key);
            dis.close();
        }
        catch(FileNotFoundException e)
        {
            System.out.println("Key file not found" + e);
        }
        catch (IOException e) {
            System.out.println("Can't read key file" + e);
        }

        byte[] codetext = null;
        try {
            File file = new File("codetext");
            FileInputStream codefile = new FileInputStream(file);
            codetext = new byte[(int)file.length()];

            DataInputStream dis = new DataInputStream(codefile);
            dis.readFully(codetext);
            dis.close();
        }
        catch(FileNotFoundException e)
        {
            System.out.println("Code file not found" + e);
        }
        catch (IOException e) {
            System.out.println("Can't read code file" + e);
        }

        try {

            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            
            PKCS8EncodedKeySpec privSpec = new PKCS8EncodedKeySpec(key);
            RSAPrivateKey rsakey = (RSAPrivateKey) keyFactory.generatePrivate(privSpec);

            Cipher c = Cipher.getInstance("RSA/ECB/PKCS1Padding");

            c.init(Cipher.DECRYPT_MODE, rsakey);
            byte[] decrypted = c.doFinal(codetext);
            System.out.println("Decrypted text:");
            System.out.println(new String(decrypted));

        }
        catch (NoSuchAlgorithmException e) {
            System.out.println("Wrong Algorithm " + e);
        }   
        catch (InvalidKeyException e) {
            System.out.println("Invalid key " + e);
        }   
        catch (IllegalBlockSizeException e) {
            System.out.println("Illegal block size" + e);
        }   
        catch (NoSuchPaddingException e) {
            System.out.println("Illegal padding " + e);
        }   
        catch (BadPaddingException e) {
            System.out.println("Bad padding " + e);
        }   
        catch (InvalidKeySpecException e) {
            System.out.println("Invalid keyspec " + e);
        }   
    }
}
------------------------------------------------------------------------
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From sean.kemplay at gmail.com  Mon Jul 27 07:14:10 2009
From: sean.kemplay at gmail.com (Sean Kemplay)
Date: Mon, 27 Jul 2009 04:14:10 -0700 (PDT)
Subject: Free hosting for open source Python projects
Message-ID: <97378723-7e67-415b-84bb-06d1675f2e2b@n11g2000yqb.googlegroups.com>

Hi All,

If anyone is looking for somewhere to host their Python project /
modules etc. for free,  please get in touch with me.  There of course
are some restraints on disk space and bandwidth but they should be
sufficient for most projects.  Your project must be open source.

You will have access to both Django or Plone/Zope(shared).  No PHP etc
- this is a Python only host.

Unfortunately I can't host everyone but if I can't host your
particular project now, I may be able to at a later stage.

Please contact me at "postmaster (at) pythonicity.co.uk".  Our website
is located at www.pythonicity.co.uk if you want to see what we do.

Best Regards,
Sean Kemplay



From wilk at flibuste.net  Mon Jul 27 07:16:15 2009
From: wilk at flibuste.net (William Dode)
Date: 27 Jul 2009 11:16:15 GMT
Subject: ANN: Shed Skin 0.2, an experimental (restricted) Python-to-C++
	compiler
References: <mailman.3393.1248013860.8015.python-list@python.org>
	<4a645b81$0$12974$426a74cc@news.free.fr>
	<29b7919a-ff4b-44eb-bad3-697274b66b6b@j32g2000yqh.googlegroups.com>
	<e7f16d88-87cd-4ad4-b44f-4b73a0a4f1dc@o7g2000yqb.googlegroups.com>
	<4a657a11$0$417$426a74cc@news.free.fr>
	<4e6df236-bbcd-4c1f-becf-3f23c0ba35bb@b15g2000yqd.googlegroups.com>
	<4a66fa20$0$11368$426a74cc@news.free.fr>
	<b0afe5f7-0cd9-43af-ba1e-0e405d5ceb5f@h21g2000yqa.googlegroups.com>
Message-ID: <4a6d8c7f$0$19614$426a74cc@news.free.fr>

On 27-07-2009, Bearophile wrote:
> William Dode':
>> I updated the script (python, c and java) with your unrolled version
>> + somes litle thinks.
> [...]
>> c 1.85s
>> gcj 2.15s
>> java 2.8s
>> python2.5 + psyco 3.1s
>> unladen-2009Q2 145s (2m45)
>> python2.5 254s (4m14s)
>> python3.1 300s (5m)
>> ironpython1.1.1 680s (11m20)
>
> Sorry for being late, I was away.
>
> In your last C version this code is useless because the C compiler is
> able to perform such simple optimization by itself (but probably
> Python isn't able, so if you want the code to be the similar in all
> versions it may be better to keep it):

I wanted so, specialy if it doesn't change a lot of the result (the 
difference is so small that i cannot see it)...

...

> I have tried your latest C version using your compiler options, my
> MinGW based on GCC 4.3.2 produces a crash at runtime.

Maybe because of -msse2 ?

> Using LLVM-GCC
> it runs in 1.31 seconds. The D version is a bit less optimized than
> your last C versions, yet using DMD it runs in 1.08-1.10 seconds.
> Let's see if someone is able to write a C version faster than that D
> code :-)
>
> Have you have compiled/read my D version? In the D version you may
> have missed that I did use an extra trick: unsigned integers, so it
> needs just two tests to see if a number is in the 0-5, 0-5 square :-)

I didn't see, fine ! But the difference is also too small to see...

> Note that Pyd, the Python-D bridge, may work with the latest DMD
> version still (and it works if you use a bit older DMD compiler):
> http://pyd.dsource.org/

I completly don't know anything about D... When i see the result of 
psyco or shedskin, i'm affraid i'll not look somewhere else soon !

However, i'd like to see a lisp implementation of this...

bye

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From davea at ieee.org  Mon Jul 27 07:21:44 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 07:21:44 -0400
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
In-Reply-To: <f2e7a4240907270033g277018a0oe687025ffdd2c083@mail.gmail.com>
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>	
	<4A69A82D.8090301@ieee.org>
	<f2e7a4240907270033g277018a0oe687025ffdd2c083@mail.gmail.com>
Message-ID: <4A6D8DC8.40304@ieee.org>

(forwarding this message, as the reply was off-list)
Kim Hansen wrote:
> 2009/7/24 Dave Angel <davea at ieee.org>:
>   
>> It's not a question of how much disk space there is, but how much virtual
>> space 32 bits can address.  2**32 is about 4 gig, and Windows XP reserves
>> about half of that for system use.  Presumably a 64 bit OS would have a much
>> larger limit.
>>
>> Years ago I worked on Sun Sparc system which had much more limited shared
>> memory access, due to hardware limitations.  So 2gig seems pretty good to
>> me.
>>
>> There is supposed to be a way to tell the Windows OS to only use 1 gb of
>> virtual space, leaving 3gb for application use.  But there are some
>> limitations, and I don't recall what they are.  I believe it has to be done
>> globally (probably in Boot.ini), rather than per process.  And some things
>> didn't work in that configuration.
>>
>> DaveA
>>
>>
>>     
> Hi Dave,
>
> In the related post I did on the numpy discussions:
>
> http://article.gmane.org/gmane.comp.python.numeric.general/31748
>
> another user was kind enough to run my test program on both 32 bit and
> 64 bit machines. On the 64 bit machine, there was no such limit, very
> much in line with what you wrote. Adding the /3GB option in boot.ini
> did not increase the available memory as well. Apparently, Python
> needs to have been compiled in a way, which makes it possible to take
> advantage of that switch and that is either not the case or I did
> something else wrong as well.
>
> I acknowledge the explanation concerning the address space available.
> Being an ignorant of the inner details of the implementation of mmap,
> it seems like somewhat an "implementation detail" to me that such an
> address wall is hit. There may be some good arguments from a
> programming point of view and it may be a relative high limit as
> compared to other systems but it is certainly at the low side for my
> application: I work with data files typically 200 GB in size
> consisting of datapackets each having a fixed size frame and a
> variable size payload. To handle these large files, I generate an
> "index" file consisting of just the frames (which has all the metadata
> I need for finding the payloads I am interested in) and "pointers" to
> where in the large data file each payload begins. This index file can
> be up to 1 GB in size and at times I need to have access to two of
> those at the same time (and then i hit the address wall). I would
> really really like to be able to access these index files in a
> read-only manner as an array of records on a file for which I use
> numpy.memmap (which wraps mmap.mmap) such that I can pick a single
> element, extract, e.g., every thousand value of a specific field in
> the record using the convenient indexing available in Python/numpy.
> Now it seems like I have to resort to making my own encapsulation
> layer, which seeks to the relevant place in the file, reads sections
> as bytestrings into recarrays, etc. Well, I must just get on with
> it...
>
> I think it would be worthwhile specifying this 32 bit OS limitation in
> the documentation of mmap.mmap, as I doubt I am the only one being
> surprised about this address space limitation.
>
> Cheers,
> Kim
>
>   
I agree that some description of system limitations should be included 
in a system-specific document.  There probably is one, I haven't looked 
recently.  But I don't think it belongs in mmap documentation.

Perhaps you still don't recognize what the limit is.  32 bits can only 
address 4 gigabytes of things as first-class addresses.  So roughly the 
same limit that's on mmap is also on list, dict, bytearray, or anything 
else.  If you had 20 lists taking 100 meg each, you would fill up 
memory.  If you had 10 of them, you might have enough room for a 1gb 
mmap area.  And your code takes up some of that space, as well as the 
Python interpreter, the standard library, and all the data structures 
that are normally ignored by the application developer.

BTW,  there is one difference between mmap and most of the other 
allocations.  Most data is allocated out of the swapfile, while mmap is 
allocated from the specified file (unless you use -1 for fileno).  
Consequently, if the swapfile is already clogged with all the other 
running applications, you can still take your 1.8gb or whatever of your 
virtual space, when much less than that might be available for other 
kinds of allocations.

Executables and dlls are also (mostly) mapped into memory just the same 
as mmap.  So they tend not to take up much space from the swapfile.  In 
fact, with planning, a DLL needn't take up any swapfile space (well, a 
few K is always needed, realistically)..  But that's a linking issue for 
compiled languages.

DaveA



From mdekauwe at gmail.com  Mon Jul 27 07:24:31 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 04:24:31 -0700 (PDT)
Subject: quickly looping over a 2D array?
Message-ID: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>

Hi,

I am new to python and I was wondering if there was a way to speed up
the way I index 2D arrays when I need to check two arrays
simultaneously? My current implementations is (using numpy) something
like the following...

for i in range(numrows):
    for j in range(numcols):

        if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
j] * some_other_value
            array_1[i, j] = some_new_value

Many Thanks,

Martin


From michael at stroeder.com  Mon Jul 27 07:35:15 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Mon, 27 Jul 2009 13:35:15 +0200
Subject: RSA cryptography between Python and Java
In-Reply-To: <m2skgibcyc.fsf@cs.uu.nl>
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com> <m2skgibcyc.fsf@cs.uu.nl>
Message-ID: <j0g0k6-i65.ln1@nb2.stroeder.com>

Piet van Oostrum wrote:
> Please note that the text to be encrypted must be smaller than the key
> size (at least 11 bytes smaller). You shouldn't encrypt large data with
> RSA anyway: it is too slow. Normally you would encrypt a session key
> with RSA and encrypt the data with the session key using a symmetric
> algorithms like AES.

I'd use CMS (AKA PKCS#7) for encrypted/signed data with X.509 certs. One
should not invent another message format.

Ciao, Michael.

-- 
Michael Str?der
E-Mail: michael at stroeder.com
http://www.stroeder.com


From __peter__ at web.de  Mon Jul 27 07:42:48 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 13:42:48 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
Message-ID: <h4k3ro$719$00$1@news.t-online.com>

Martin wrote:

> I am new to python and I was wondering if there was a way to speed up
> the way I index 2D arrays when I need to check two arrays
> simultaneously? My current implementations is (using numpy) something
> like the following...
> 
> for i in range(numrows):
>     for j in range(numcols):
> 
>         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
> j] * some_other_value
>             array_1[i, j] = some_new_value

array_1[(array_1 == some_value) | (array_2 >= array_1 * some_other_value)] = 
some_new_value

maybe?



From nogetfx at gmail.com  Mon Jul 27 07:48:30 2009
From: nogetfx at gmail.com (Lars)
Date: Mon, 27 Jul 2009 04:48:30 -0700 (PDT)
Subject: Call function from another class
References: <4b6b0e4b-b85b-43cf-a695-e3a722de01cc@e11g2000yqo.googlegroups.com>
	<7d5em2F2anm94U1@mid.uni-berlin.de>
Message-ID: <f8fd35e5-1307-4957-8f28-002068d42637@t13g2000yqt.googlegroups.com>

> If I'm not mistaken, in "doRotate" you should be able to refer to the
> to-be-closed dialog via
> self.frameRotate
>
> Now if you change the "sliderUpdate"-code to store that angle instead of
> just letting it fall out of scope, you could access that value through
> frameRotate:
>
> def sliderUpdate(self, event):
> ? ? ? ? angle=self.slider.GetValue()
> ? ? ? ? ROTATION_ANGLE=angle
> ? ? ? ? self.angle = angle
> ? ? ? ? self.Destroy()
>
> def doRotate(self,event):
> ? ? """Rotating image"""
> ? ? print self.frameRotate.angle

Thanks for replying. If Bind is used in "onRotate":
def onRotate(self,event):
       """Rotate image"""
       self.frameRotate = rotationSlider(parent=None, id=-1)
       self.Bind(wx.EVT_CLOSE,self.doRotate, self.frameRotate.Destroy)
       self.frameRotate.Show()

Then i get:
Traceback (most recent call last):
  File "viewer_sep.py", line 136, in onRotate
    self.Bind(wx.EVT_CLOSE,self.doRotate, self.frameRotate.Destroy)
  File "/usr/lib/python2.5/site-packages/wx-2.6-gtk2-unicode/wx/
_core.py", line 3629, in Bind
    id  = source.GetId()
AttributeError: 'function' object has no attribute 'GetId'

My experience with ID is setting it to "-1".  So I'm not sure if it is
a wrong use of Bind or an wxPython error.
/Lars


From Slaunger at gmail.com  Mon Jul 27 07:50:52 2009
From: Slaunger at gmail.com (Slaunger)
Date: Mon, 27 Jul 2009 04:50:52 -0700 (PDT)
Subject: mmap 2GB allocation limit on Win XP, 32-bits, Python 2.5.4
References: <f6556b58-5899-492a-b9ad-c4c1b6cc7619@18g2000yqa.googlegroups.com>
	<4A69A82D.8090301@ieee.org>
	<f2e7a4240907270033g277018a0oe687025ffdd2c083@mail.gmail.com> 
	<mailman.3767.1248693717.8015.python-list@python.org>
Message-ID: <ca1180e7-1f20-492d-9edb-ba9e04bcecc3@h11g2000yqb.googlegroups.com>

On 27 Jul., 13:21, Dave Angel <da... at ieee.org> wrote:
> (forwarding this message, as the reply was off-list)
>
>
>
> Kim Hansen wrote:
> > 2009/7/24 Dave Angel <da... at ieee.org>:
>
> >> It's not a question of how much disk space there is, but how much virtual
> >> space 32 bits can address. ?2**32 is about 4 gig, and Windows XP reserves
> >> about half of that for system use. ?Presumably a 64 bit OS would have a much
> >> larger limit.
>
> >> Years ago I worked on Sun Sparc system which had much more limited shared
> >> memory access, due to hardware limitations. ?So 2gig seems pretty good to
> >> me.
>
> >> There is supposed to be a way to tell the Windows OS to only use 1 gb of
> >> virtual space, leaving 3gb for application use. ?But there are some
> >> limitations, and I don't recall what they are. ?I believe it has to be done
> >> globally (probably in Boot.ini), rather than per process. ?And some things
> >> didn't work in that configuration.
>
> >> DaveA
>
> > Hi Dave,
>
> > In the related post I did on the numpy discussions:
>
> >http://article.gmane.org/gmane.comp.python.numeric.general/31748
>
> > another user was kind enough to run my test program on both 32 bit and
> > 64 bit machines. On the 64 bit machine, there was no such limit, very
> > much in line with what you wrote. Adding the /3GB option in boot.ini
> > did not increase the available memory as well. Apparently, Python
> > needs to have been compiled in a way, which makes it possible to take
> > advantage of that switch and that is either not the case or I did
> > something else wrong as well.
>
> > I acknowledge the explanation concerning the address space available.
> > Being an ignorant of the inner details of the implementation of mmap,
> > it seems like somewhat an "implementation detail" to me that such an
> > address wall is hit. There may be some good arguments from a
> > programming point of view and it may be a relative high limit as
> > compared to other systems but it is certainly at the low side for my
> > application: I work with data files typically 200 GB in size
> > consisting of datapackets each having a fixed size frame and a
> > variable size payload. To handle these large files, I generate an
> > "index" file consisting of just the frames (which has all the metadata
> > I need for finding the payloads I am interested in) and "pointers" to
> > where in the large data file each payload begins. This index file can
> > be up to 1 GB in size and at times I need to have access to two of
> > those at the same time (and then i hit the address wall). I would
> > really really like to be able to access these index files in a
> > read-only manner as an array of records on a file for which I use
> > numpy.memmap (which wraps mmap.mmap) such that I can pick a single
> > element, extract, e.g., every thousand value of a specific field in
> > the record using the convenient indexing available in Python/numpy.
> > Now it seems like I have to resort to making my own encapsulation
> > layer, which seeks to the relevant place in the file, reads sections
> > as bytestrings into recarrays, etc. Well, I must just get on with
> > it...
>
> > I think it would be worthwhile specifying this 32 bit OS limitation in
> > the documentation of mmap.mmap, as I doubt I am the only one being
> > surprised about this address space limitation.
>
> > Cheers,
> > Kim
>
> I agree that some description of system limitations should be included
> in a system-specific document. ?There probably is one, I haven't looked
> recently. ?But I don't think it belongs in mmap documentation.
>
> Perhaps you still don't recognize what the limit is. ?32 bits can only
> address 4 gigabytes of things as first-class addresses. ?So roughly the
> same limit that's on mmap is also on list, dict, bytearray, or anything
> else. ?If you had 20 lists taking 100 meg each, you would fill up
> memory. ?If you had 10 of them, you might have enough room for a 1gb
> mmap area. ?And your code takes up some of that space, as well as the
> Python interpreter, the standard library, and all the data structures
> that are normally ignored by the application developer.
>
> BTW, ?there is one difference between mmap and most of the other
> allocations. ?Most data is allocated out of the swapfile, while mmap is
> allocated from the specified file (unless you use -1 for fileno). ?
> Consequently, if the swapfile is already clogged with all the other
> running applications, you can still take your 1.8gb or whatever of your
> virtual space, when much less than that might be available for other
> kinds of allocations.
>
> Executables and dlls are also (mostly) mapped into memory just the same
> as mmap. ?So they tend not to take up much space from the swapfile. ?In
> fact, with planning, a DLL needn't take up any swapfile space (well, a
> few K is always needed, realistically).. ?But that's a linking issue for
> compiled languages.
>
> DaveA- Skjul tekst i anf?rselstegn -
>
> - Vis tekst i anf?rselstegn -

I do understand the 2 GB address space limitation. However, I think I
have found a solution to my original numpy.memmap problem (which spun
off to this problem), and that is PyTables, where I can address 2^64
data on a 32 bit machine using hd5 files and thus circumventing the
"implementation detail" of the intermedia 2^32 memory address problem
in the numpy.memmap/mmap.mmap implementation.

http://www.pytables.org/moin

I just watched the first tutorial video, and that seems like just what
I am after (if it works as well in practise at it appears to do).

http://showmedo.com/videos/video?name=1780000&fromSeriesID=178

Cheers,
Kim


From piet at cs.uu.nl  Mon Jul 27 07:51:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 13:51:34 +0200
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
Message-ID: <m2ocr6bayh.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()

By the way, a PEM file is a text file, no reason to open it in binary
mode. Just replace the 'rb' with 'r' or leave it out.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Mon Jul 27 08:19:49 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 14:19:49 +0200
Subject: RSA cryptography between Python and Java
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
	<7xocr8si30.fsf@ruckus.brouhaha.com> <m2skgibcyc.fsf@cs.uu.nl>
	<j0g0k6-i65.ln1@nb2.stroeder.com>
Message-ID: <m2fxcib9ne.fsf@cs.uu.nl>

>>>>> Michael Str?der <michael at stroeder.com> (MS) wrote:

>MS> Piet van Oostrum wrote:
>>> Please note that the text to be encrypted must be smaller than the key
>>> size (at least 11 bytes smaller). You shouldn't encrypt large data with
>>> RSA anyway: it is too slow. Normally you would encrypt a session key
>>> with RSA and encrypt the data with the session key using a symmetric
>>> algorithms like AES.

>MS> I'd use CMS (AKA PKCS#7) for encrypted/signed data with X.509 certs. One
>MS> should not invent another message format.

Yes but the original question was not about X.509 certs. Just the RSA
public key. I don't know what the OP wants to do with it.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From drobinow at gmail.com  Mon Jul 27 08:20:48 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 27 Jul 2009 07:20:48 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4A6CC3BE.6060806@mrabarnett.plus.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<4A6CC3BE.6060806@mrabarnett.plus.com>
Message-ID: <4eb0089f0907270520n782503b1ndc34bcb1cf14a47e@mail.gmail.com>

On 7/26/09, MRAB <python at mrabarnett.plus.com> wrote:
> David Robinow wrote:
> > > This doesn't mean they're on the same level - in fact, if you read
> carefully
> > > you'll see my original post said as much: python attracted average
> > > programmers; php attracted mediocre programmers and even some
> > > non-programmers, which means that php is clearly a lesser language than
> > > python.
> >  I'm a mediocre programmer. Does this mean I should switch to PHP?
> If you're a mediocre programmer who knows you're mediocre, but wants to
> improve and is willing to learn, then stick with Python. You'll get
> better. :-)
I doubt it. I remember when Guido moved to the U.S. and I've even used
stdwin. I've actually gotten worse over the years. Old age does that.
Nevertheless, I question the idea that a language that is easy to use
(I don't know if PHP qualifies) is somehow inferior.


From mdekauwe at gmail.com  Mon Jul 27 08:27:11 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 05:27:11 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
Message-ID: <503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>

On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > I am new to python and I was wondering if there was a way to speed up
> > the way I index 2D arrays when I need to check two arrays
> > simultaneously? My current implementations is (using numpy) something
> > like the following...
>
> > for i in range(numrows):
> >     for j in range(numcols):
>
> >         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
> > j] * some_other_value
> >             array_1[i, j] = some_new_value
>
> array_1[(array_1 == some_value) | (array_2 >= array_1 * some_other_value)] =
> some_new_value
>
> maybe?

So I tried...

band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0

which led to

ValueError: The truth value of an array with more than one element is
ambiguous. Use a.any() or a.all()

so not sure that works?


From rlichlighter at gmail.com  Mon Jul 27 08:29:23 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 05:29:23 -0700 (PDT)
Subject: Convert raw binary file to ascii
Message-ID: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>

I have a memory dump from a machine I am trying to analyze. I can view
the file in a hex editor to see text strings in the binary code. I
don't see a way to save these ascii representations of the binary, so
I went digging into Python to see if there were any modules to help.

I found one I think might do what I want it to do - the binascii
module. Can anyone describe to me how to convert a raw binary file to
an ascii file using this module. I've tried? Boy, I've tried.

Am I correct in assuming I can get the converted binary to ascii text
I see in a hex editor using this module? I'm new to this forensics
thing and it's quite possible I am mixing technical terms. I am not
new to Python, however. Thanks for your help.


From electriclightheads at gmail.com  Mon Jul 27 08:29:58 2009
From: electriclightheads at gmail.com ('2+)
Date: Mon, 27 Jul 2009 21:29:58 +0900
Subject: wave.setparams((2, 2, 44100, 44100 * 2 * 10, "NONE", "not 
	compressed")) became more than 30secs
Message-ID: <1078018b0907270529l676fdb75k4c1f42ef0a2e7d0a@mail.gmail.com>

thanx to rob .. who gave me an example of how to use the WAVE lib
now am on my way to use it as simple as i can

i wrote an oil.py the instance of which will behave like an oscillator
which constantly generates 7 different wave forms (non fixed)
i thought this code might produce 10secs of wave file but the result
was longer than 30secs
was testing if i could use the WAVE lib withount taking advantage of
StringIO
nor
struct
but maybe am doing totally wrong?

--8<---

import oil
import wave

a = oil.Sa()

w = wave.open("current.wav", "w")
w.setparams((2, 2, 44100, 44100 * 2 * 10, "NONE", "not compressed"))

for gas in range(44100 * 10):
    a.breath()
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    w.writeframes(hex(r))
    w.writeframes(hex(l))
w.close()



-- 
SaRiGaMa's Oil Vending Orchestra
is podcasting:
http://sarigama.namaste.jp/podcast/rss.xml
and supplying oil.py for free:
http://oilpy.blogspot.com/


From benjamin.kaplan at case.edu  Mon Jul 27 08:41:23 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Mon, 27 Jul 2009 08:41:23 -0400
Subject: Help understanding the decisions *behind* python? - immutable 
	objects
In-Reply-To: <4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
Message-ID: <ec96e1390907270541p7846d649r7d8fd6e429c64a56@mail.gmail.com>

On Sun, Jul 26, 2009 at 2:24 PM, John Nagle<nagle at animats.com> wrote:
> Beni Cherniavsky wrote:
>>
>> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
>> wrote:
>>>
>>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>>
>>>> My guess is that it was probably for optimization reasons long ago.
>>>> I've never heard a *good* reason why Python needs both.
>>>
>>> The good reason is the immutability, which lets you use
>>> a tuple as a dict key.
>>
>> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
>> wrote:
>>>
>>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>>
>>>> My guess is that it was probably for optimization reasons long ago.
>>>> I've never heard a *good* reason why Python needs both.
>>>
>>> The good reason is the immutability, which lets you use
>>> a tuple as a dict key.
>>>
>> The *technical* reason is immutability for dict keys.
>> Dict could allow mutable objects as keys by comparing *by value*,
>> making a copy on insertion and hashing the current value on lookup.
>> Prior art: the 2.3 sets module allows mutable Sets as elements in
>> Sets, by making ImmutableSet copies on insertion, and hashing Sets as
>> if they are temporarily immutable on lookup.
>>
>> This inspired PEP 351 and ambitious proposals to expand the approach
>> to all Python with a copy-on-write scheme. ?But these ideas were
>> rejected, and the 2.4 builtin sets only allow frozenset elements.
>> Half the reason is technical: copy-on-write and harder than it sounds,
>> and without it you pay a performance price.
>>
>> But the deeper reason is style: immutable types are convenient!
>> The allow a pure-functional style of code, which can be simpler.
>> Of course, sometimes an imperative style is simpler. ?Depends on the
>> problem.
>
> ? ?An interesting issue is Python objects, which are always mutable.
> A "dict" of Python objects is allowed, but doesn't consider
> the contents of the objects, just their identity (address). Only
> built-in types are immutable; one cannot create a class of immutable
> objects.
> So things like "frozenset" had to be built into the language.
> A tuple is really a frozen list. ?Arguably, frozen objects
> should have been a general concept. ?Conceptually, they're
> simple - once "__init__" has run, there can be no more changes
> to fields of the object.
>
> ? ?Compare the C++ approach, where you can have a "map" of
> any object that defines the "<" operator. ?Python has
> "__cmp__" for objects, but built-in dictionaries don't use it.
> Of course, one could create a "map" class in Python that
> uses "__cmp__", which would allow dictionary-type operations
> on arbitrary objects.


Python dictionaries are hash maps so they use hashes, not comparisons,
to store objects. By default the hash is equal to the object's
identity but all you need to do to change it is define your own
__hash__ method. If you were to make a C++ hash map, it wouldn't use
comparisons either.


>
> ? ?There are some interesting uses for immutable objects in
> multithreaded programs. ?They can be shared between threads
> without locking. ?If it weren't for the infamous Global
> Interpreter Lock, which basically limits Python programs to using
> one CPU at a time, Python would have to deal with locking
> in a more advanced way. ?A system where immutable objects
> can be shared and passed between threads, and mutable objects
> must be "synchronized" (in the Java sense) to be shared would
> be useful.
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?John Nagle
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From rashidsdpk at gmail.com  Mon Jul 27 08:45:33 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Mon, 27 Jul 2009 05:45:33 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <d6433b12-1c85-4cca-a1ec-6abcab8c0d62@s31g2000yqs.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.more http://0nanotechnology0.blogspot.com/


From __peter__ at web.de  Mon Jul 27 08:46:54 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 14:46:54 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
Message-ID: <h4k7jt$ec1$00$1@news.t-online.com>

Martin wrote:

> On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
>> Martin wrote:
>> > I am new to python and I was wondering if there was a way to speed up
>> > the way I index 2D arrays when I need to check two arrays
>> > simultaneously? My current implementations is (using numpy) something
>> > like the following...
>>
>> > for i in range(numrows):
>> >     for j in range(numcols):
>>
>> >         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
>> > j] * some_other_value
>> >             array_1[i, j] = some_new_value
>>
>> array_1[(array_1 == some_value) | (array_2 >= array_1 *
>> some_other_value)] = some_new_value
>>
>> maybe?
> 
> So I tried...
> 
> band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
> 
> which led to
> 
> ValueError: The truth value of an array with more than one element is
> ambiguous. Use a.any() or a.all()
> 
> so not sure that works?

Copy and paste -- or replace "or" with "|".



From mdekauwe at gmail.com  Mon Jul 27 08:55:15 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 05:55:15 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
Message-ID: <266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>

On Jul 27, 1:46 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
> >> Martin wrote:
> >> > I am new to python and I was wondering if there was a way to speed up
> >> > the way I index 2D arrays when I need to check two arrays
> >> > simultaneously? My current implementations is (using numpy) something
> >> > like the following...
>
> >> > for i in range(numrows):
> >> >     for j in range(numcols):
>
> >> >         if array_1[i, j] == some_value or array_2[i, j] >= array_1[i,
> >> > j] * some_other_value
> >> >             array_1[i, j] = some_new_value
>
> >> array_1[(array_1 == some_value) | (array_2 >= array_1 *
> >> some_other_value)] = some_new_value
>
> >> maybe?
>
> > So I tried...
>
> > band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
>
> > which led to
>
> > ValueError: The truth value of an array with more than one element is
> > ambiguous. Use a.any() or a.all()
>
> > so not sure that works?
>
> Copy and paste -- or replace "or" with "|".

apologies - I mistook that for a type for "or"

I now get the following error...

ValueError: shape mismatch: objects cannot be broadcast to a single
shape


From __peter__ at web.de  Mon Jul 27 09:06:17 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 15:06:17 +0200
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
Message-ID: <h4k8o8$ght$00$1@news.t-online.com>

r2 wrote:

> I have a memory dump from a machine I am trying to analyze. I can view
> the file in a hex editor to see text strings in the binary code. I
> don't see a way to save these ascii representations of the binary, so
> I went digging into Python to see if there were any modules to help.
> 
> I found one I think might do what I want it to do - the binascii
> module. Can anyone describe to me how to convert a raw binary file to
> an ascii file using this module. I've tried? Boy, I've tried.

That won't work because a text editor doesn't need any help to convert the 
bytes into characters. If it expects ascii it just will be puzzled by bytes 
that are not valid ascii. Also, it will happily display byte sequences that 
are valid ascii, but that you as a user will see as gibberish because they 
were meant to be binary data by the program that wrote them.

> Am I correct in assuming I can get the converted binary to ascii text
> I see in a hex editor using this module? I'm new to this forensics
> thing and it's quite possible I am mixing technical terms. I am not
> new to Python, however. Thanks for your help.

Unix has the "strings" commandline tool to extract text from a binary.
Get hold of a copy of the MinGW tools if you are on windows.

Peter



From nemelis at gmail.com  Mon Jul 27 09:12:39 2009
From: nemelis at gmail.com (Harry Ebbers)
Date: Mon, 27 Jul 2009 06:12:39 -0700 (PDT)
Subject: Testoob: How do you use testoob.collector_from_globals / 
	collector_from_modules?
Message-ID: <1a8582cc-a7fc-4b1e-b1b2-d23e20ad6022@18g2000yqa.googlegroups.com>

Hi,

For a project I'm creating unittests using testoob. When all tests are
in a single file there is no problem

if __name__ == '__main__':
    testoob.main()
 does the trick as usual.

But for a number of python-applications they have asked me to group
unittests in different files, based on common functionality (e.g. GUI,
main-application, etcetera).

Ican get it to work by importing all unittestclasses in the following
way and than use the normal if __name__ == '__main__' construction

(from GUI import GUItests
from APP import APPtests

if __name__ == '__main__':
    testoob.main())

But looking at the future I would like to use testsuites.

On the internet I found the functions testoob.collector_from_globals
and collector_from_modules which one can use to 'easily' create
testsuites which can be used with testoob. But no examples on how to
use them can be found.

Can anybody supply me with a working example?

TIA

Harry Ebbers


From __peter__ at web.de  Mon Jul 27 09:17:58 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 15:17:58 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
Message-ID: <h4k9e6$tf9$02$1@news.t-online.com>

Martin wrote:

> On Jul 27, 1:46 pm, Peter Otten <__pete... at web.de> wrote:
>> Martin wrote:
>> > On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
>> >> Martin wrote:
>> >> > I am new to python and I was wondering if there was a way to speed
>> >> > up the way I index 2D arrays when I need to check two arrays
>> >> > simultaneously? My current implementations is (using numpy)
>> >> > something like the following...
>>
>> >> > for i in range(numrows):
>> >> >     for j in range(numcols):
>>
>> >> >         if array_1[i, j] == some_value or array_2[i, j] >=
>> >> >         array_1[i,
>> >> > j] * some_other_value
>> >> >             array_1[i, j] = some_new_value
>>
>> >> array_1[(array_1 == some_value) | (array_2 >= array_1 *
>> >> some_other_value)] = some_new_value
>>
>> >> maybe?
>>
>> > So I tried...
>>
>> > band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
>>
>> > which led to
>>
>> > ValueError: The truth value of an array with more than one element is
>> > ambiguous. Use a.any() or a.all()
>>
>> > so not sure that works?
>>
>> Copy and paste -- or replace "or" with "|".
> 
> apologies - I mistook that for a type for "or"
> 
> I now get the following error...
> 
> ValueError: shape mismatch: objects cannot be broadcast to a single
> shape

It seems array_1 and array_2 have a -- dada! -- different shape.
Assuming array_1 is the smaller one:

numrows, numcols = array_1.shape
array_1[(array_1 == some_value) | (array_2[:numrows,:numcols] >= array_1 * 
some_other_value)] = some_new_value

There may be other options, but I'm not a numpy expert.

Peter



From constant.beta at gmail.com  Mon Jul 27 09:46:01 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Mon, 27 Jul 2009 06:46:01 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<mailman.3715.1248552511.8015.python-list@python.org>
	<2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>
	<h4iqgb$ss5$1@panix3.panix.com>
Message-ID: <1c8ae01e-2e9c-497c-9f8d-408f56f9c0bd@g31g2000yqc.googlegroups.com>

On Jul 27, 1:56 am, a... at pythoncraft.com (Aahz) wrote:
> >> Upon a cursory look, after a generator 'gen' is exhausted (meaning
> >> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
> >> None.
>
> >Only in Python 2.5 or higher though. I need to support Python 2.3 and
> >2.4 as well, sorry for not making that clear in the original post.
>
> Are you sure?  It appears to work in Python 2.4; I don't have time to
> check 2.3.

No, it does not work in Python 2.4. gi_frame can be None only in
Python 2.5 and higher.

Via "What?s New in Python 2.5" (http://docs.python.org/whatsnew/
2.5.html):

"""
Another even more esoteric effect of this change: previously, the
gi_frame attribute of a generator was always a frame object. It?s now
possible for gi_frame to be None once the generator has been
exhausted.
"""

Cheers,
mk


From sjmachin at lexicon.net  Mon Jul 27 09:57:26 2009
From: sjmachin at lexicon.net (John Machin)
Date: Mon, 27 Jul 2009 06:57:26 -0700 (PDT)
Subject: Problem in PyArg_ParseTuple on python 2.5.2 with AIX
References: <370cfa30-697f-4a82-a577-1eb951424f5a@e11g2000yqo.googlegroups.com>
	<635a7311-62e1-4da5-98ad-b62cfa150287@k30g2000yqf.googlegroups.com> 
	<43b1acda-b518-40ef-acde-145e28379775@r25g2000vbn.googlegroups.com>
Message-ID: <281196a8-c392-4818-b2fb-6b60c84aba2a@j21g2000vbn.googlegroups.com>

On Jul 27, 8:49?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
> On Jul 27, 2:25?pm, John Machin <sjmac... at lexicon.net> wrote:
>
>
>
> > On Jul 27, 5:11?pm, abhi <abhigyan_agra... at in.ibm.com> wrote:
>
> > > Hi,
> > > ? ? I am facing a problem using PyArg_ParseTuple() in my C-API
> > > extension. Here is a small repro of the function:
>
> > > static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> > > {
> > > ? ? ? ? SQLUSMALLINT param_no = 0;
>
> > Sorry, my crystal ball is on the fritz. What is SQLUSMALLINT on
> > Windows/Linux/AIX?
> > What does
> > ? ? printf("%d %d %d\n", sizeof(SQLUSMALLINT), sizeof(int), sizeof
> > (long));
> > give you on each platform?

And the answer was: what?

> ? ? Thanks for the response. If I don't use SQLUSMALLINT and use int
> instead, then also I see the same problem.
> static PyObject *parsetuple_test(PyObject *self, PyObject *args)
> ?{
> ? ? ? ? int param_no = 0;
> ....
> ....}
>
> This also prints out 0 for AIX and actual value passed in other
> platforms. If I initialize param_no with some other value (e.g. 90),
> it prints out that value.

Please run the following on AIX with Python 2.5:
   import sys
   print sys.byteorder, sys.maxint
   print sys.version
and tell us the output.

Does the C compiler that you are using for the extension correspond
with whatever is mentioned in sys.version about the C compiler used to
compile Python 2.5?

C code: Please add/change as follows:
   int dummy1 = 0xaaaabbbb;
   int param_no = 0xccccdddd;
   int dummy2 = 0xeeeeffff;
...
   printf("%08x %08x %08x\n", dummy1, param_no, dummy2);
   printf("%d %d\n", sizeof(int), sizeof(long));

Try this on AIX (a) with no optimisation (b) whatever O level you have
been using.

Try it with (i) small positive input (i) integer > 65535

Take a copy of your extension and cut out everything that is not part
of executing this function i.e. apart from this function (with the
dummies and printfs) you should have only a few includes, a table
defining just 1 callable function, and the minimal module
initialisation code. Check that this cut down version works on Windows
and Linux and still fails on AIX. Then try it without the first ("O")
arg. If it still fails on AIX, lose the first arg. Publish the minimal
failing code, the instructions to build the .so, and a transcript of
the Python interactive session showing calling the function and the
results.

Cheers,
John


From mdekauwe at gmail.com  Mon Jul 27 10:01:18 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 07:01:18 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
	<h4k9e6$tf9$02$1@news.t-online.com>
Message-ID: <8b78b47f-799e-4d37-bc28-d1ed349362c9@k6g2000yqn.googlegroups.com>

On Jul 27, 2:17 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > On Jul 27, 1:46 pm, Peter Otten <__pete... at web.de> wrote:
> >> Martin wrote:
> >> > On Jul 27, 12:42 pm, Peter Otten <__pete... at web.de> wrote:
> >> >> Martin wrote:
> >> >> > I am new to python and I was wondering if there was a way to speed
> >> >> > up the way I index 2D arrays when I need to check two arrays
> >> >> > simultaneously? My current implementations is (using numpy)
> >> >> > something like the following...
>
> >> >> > for i in range(numrows):
> >> >> >     for j in range(numcols):
>
> >> >> >         if array_1[i, j] == some_value or array_2[i, j] >=
> >> >> >         array_1[i,
> >> >> > j] * some_other_value
> >> >> >             array_1[i, j] = some_new_value
>
> >> >> array_1[(array_1 == some_value) | (array_2 >= array_1 *
> >> >> some_other_value)] = some_new_value
>
> >> >> maybe?
>
> >> > So I tried...
>
> >> > band_1[(array_1 == 255) or (array_2 >= array_1 * factor)] = 0
>
> >> > which led to
>
> >> > ValueError: The truth value of an array with more than one element is
> >> > ambiguous. Use a.any() or a.all()
>
> >> > so not sure that works?
>
> >> Copy and paste -- or replace "or" with "|".
>
> > apologies - I mistook that for a type for "or"
>
> > I now get the following error...
>
> > ValueError: shape mismatch: objects cannot be broadcast to a single
> > shape
>
> It seems array_1 and array_2 have a -- dada! -- different shape.
> Assuming array_1 is the smaller one:
>
> numrows, numcols = array_1.shape
> array_1[(array_1 == some_value) | (array_2[:numrows,:numcols] >= array_1 *
> some_other_value)] = some_new_value
>
> There may be other options, but I'm not a numpy expert.
>
> Peter

My mistake - the incorrect size in the arrays was my error.

The statement works now, but it doesn't give the same results as my
original logic, strangely!?

in my logic:

data = np.zeros((numrows, numcols), dtype = np.uint8, order ='C')

for i in range(numrows):
    for j in range(numcols):
        if band3[i,j] == 255 or band3[i,j] >= band6[i,j] * factor:
            data[i,j] = 0
        else:
            data[i,j] = 1

to do the same with what you suggested...

data = np.ones((numrows, numcols), dtype = np.uint8, order ='C')
data[(band3 == 255) | (band6 >= band3 * factor)] = 0

Thanks


From santhosh.vkumar at gmail.com  Mon Jul 27 10:04:48 2009
From: santhosh.vkumar at gmail.com (santhoshvkumar)
Date: Mon, 27 Jul 2009 07:04:48 -0700 (PDT)
Subject: iText for Python
Message-ID: <505f2bc1-cbfb-49a1-a7ef-0b6c357750a7@q35g2000vbi.googlegroups.com>

Hi all,
           One of my cousin  suggested me to do a IText PDF converter
for python. Actually I heard that there is no separate IText converter
either we have to go for jython or GCJ with wrapper. Instead of
wrapping, my plan is to create a separate module with Python and I am
thinking of doing this in as my final year project also. Kindly give
me your suggestion.

        With anticipation,

SanthoshVKumar.


From jeanmichel at sequans.com  Mon Jul 27 10:05:11 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 27 Jul 2009 16:05:11 +0200
Subject: Override a method but inherit the docstring
In-Reply-To: <87r5wggm0y.fsf@benfinney.id.au>
References: <87r5wggm0y.fsf@benfinney.id.au>
Message-ID: <4A6DB417.5080601@sequans.com>

Ben Finney wrote:
> Howdy all,
>
> The following is a common idiom::
>
>     class FooGonk(object):
>         def frobnicate(self):
>             """ Frobnicate this gonk. """
>             basic_implementation(self.wobble)
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>
> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> the method, the original docstring is not associated with it.
>
> Ideally there would be a way to specify that the docstring should be
> inherited. The best I can come up with is::
>
>     class BarGonk(FooGonk):
>         def frobnicate(self):
>             special_implementation(self.warble)
>         frobnicate.__doc__ = FooGonk.frobnicate.__doc__
>
> but that violates DRY (the association between BarGonk and FooGonk is
> being repeated), puts the docstring assignment awkwardly after the end
> of the method instead of at the beginning where docstrings normally go,
> and reads poorly besides.
>
> What is the most Pythonic, DRY-adherent, and preferably least-ugly
> approach to override a method, but have the same docstring on both
> methods?
>
>   
I am using epydoc and if the docstring is present only in the baseclass 
method, it will repeat the docstring for the child methods. So 
basically, there's nothing to do.
I've also tried within the python interpreter, and it can perfectly 
solve docstring inheritance. So why would you explicitly assign 
docstring to child methods ?

JM


From invalid at invalid  Mon Jul 27 10:11:21 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 27 Jul 2009 09:11:21 -0500
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
Message-ID: <PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>

On 2009-07-27, r2 <rlichlighter at gmail.com> wrote:

> I have a memory dump from a machine I am trying to analyze. I can view
> the file in a hex editor to see text strings in the binary code. I
> don't see a way to save these ascii representations of the binary,

$ strings memdump.binary >memdump.strings

$ hexdump -C memdump.binary >memdump.hex+ascii

-- 
Grant Edwards                   grante             Yow! I'm ZIPPY the PINHEAD
                                  at               and I'm totally committed
                               visi.com            to the festive mode.


From jeanmichel at sequans.com  Mon Jul 27 10:17:13 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Mon, 27 Jul 2009 16:17:13 +0200
Subject: How to comment constant values?
In-Reply-To: <027cd65b$0$5185$c3e8da3@news.astraweb.com>
References: <200907270749.58845.devent@deventm.org>	<mailman.3750.1248645992.8015.python-list@python.org>	<7d44ndF29p3p7U2@mid.uni-berlin.de>
	<027cd65b$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <4A6DB6E9.3020308@sequans.com>

Steven D'Aprano wrote:
> On Mon, 27 Jul 2009 00:47:08 +0200, Diez B. Roggisch wrote:
>
>   
>>> Only modules, classes, and functions/methods can have docstrings
>>> associated with them.
>>> For anything else, you have to use comments; or you can mention them in
>>> the docstrings of related things.
>>>       
>> While this is technically true, writing docstrings to constants (module
>> or classlevel) works when one uses tools such as epydoc to generate
>> documentation.
>>     
>
> I've never used epydoc, so I'm not sure what you mean. Presumably it uses 
> source code analysis to detect:
>
> CONSTANT = 42
> """This is a constant."""
>
> even though the string is ignored by the compiler.
>
> Is that correct?
>
>
>   
Yes, and because it is perfectly ignored by the compiler there's no harm 
using this feature. I would add that even if you're not using epydoc, 
having a way top discriminate comments from documentation is 
recommended, their purpose are definitely not the same.

JM


From piet at cs.uu.nl  Mon Jul 27 10:23:04 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Mon, 27 Jul 2009 16:23:04 +0200
Subject: python function for retrieving key and encryption
References: <19aa84c7-2268-41c4-809e-88e6dabd656f@h18g2000yqj.googlegroups.com>
	<m2iqhmm3gs.fsf@cs.uu.nl>
	<b86a241a-ae4b-4fd7-991a-5c309ec4bcfc@b14g2000yqd.googlegroups.com>
	<m2ocrbk1k2.fsf@cs.uu.nl>
	<e004759b-4fd5-49b4-b3a6-1e2063a9aed9@v36g2000yqv.googlegroups.com>
Message-ID: <m23a8ib3xz.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>j> import M2Crypto
>j> from M2Crypto import RSA,SSL
>j> def encrypt():
>j>     pk = open('my_key.public.pem', 'rb').read()
>j>     rsa = M2Crypto.RSA.load_pub_key(pk) #return a M2Crypto.RSA.RSA_pub
>j> object.
>j>     plaintext = 4545479545655576767767686688782344
>j>     msg = rsa.public_encrypt(plaintext,RSA.pkcs1_padding)
>j>     print msg;
>j>     encrypt()

>j> This is code i am refering.
>j> The Problem is coming with .pem file.

You never tell what the problem is. Which error message do you get? Why
can't you just copy the error messages in your post instead of letting
us guess what is happening?

There are indeed problems with the code above. One warning: If you are
going to write cryptographic code while you really don't understand the
subject enough there is a big chance that your programs will have
security problems.

One more question: Do you have now a valid my_key.public.pem file? And
is it in the same directory where you run this program?

Here are the problems in your code (and there may be more!)

  import M2Crypto
  from M2Crypto import RSA,SSL

You never use the imports from the line above so you can leave it out.
SSL isn't used at all, and RSA is used as M2Crypto.RSA so it uses the
first import. Cleanliness is next to godliness.

  def encrypt():
      pk = open('my_key.public.pem', 'rb').read()
      rsa = M2Crypto.RSA.load_pub_key(pk) #return a M2Crypto.RSA.RSA_pub object.

load_pub_key requires a file name, not the contents of the file.
So use rsa = M2Crypto.RSA.load_pub_key('my_key.public.pem') and leave
the open line out.

      plaintext = 4545479545655576767767686688782344

That's not text, it is a number. rsa.public_encrypt will not accept a
number. So you would have to use 
      plaintext = "4545479545655576767767686688782344"
or convert the number to a byte array.

      msg = rsa.public_encrypt(plaintext,RSA.pkcs1_padding)
      print msg;
      encrypt()

The above line should be shifted to the left. It is not part of the
function otherwise you get an endless recursion.
And to answer another question from stackoverflow.com: RSA.pkcs1_padding
is a good parameter, if the decryption side will also use it.

See also my posting on the subject `RSA cryptography between Python and Java'.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From skip at pobox.com  Mon Jul 27 10:26:42 2009
From: skip at pobox.com (skip at pobox.com)
Date: Mon, 27 Jul 2009 09:26:42 -0500 (CDT)
Subject: Wrapping prstat on Solaris
Message-ID: <20090727142642.947081188353@montanaro.dyndns.org>

At work we currently use top to monitor ongoing system utilization on our
Solaris systems.  As time has moved on though, use of top has become
problematic.  Our admins want us to switch to prstat, Sun's top-like
command.  It works fine however doesn't emit a timestamp at each display
interval, so it's essentially impossible looking at a prstat output
file to determine when the particular "screen" was emitted.

If figured, "No problem.  I'll just write a little wrapper."  Alas, that is
proving harder than I thought.  I can run prstat directing output to a file
and it seems to blast out a block of lines every N seconds, but when run
from inside a Python script I can't seem to make the damn thing not
massively buffer its output.  Accordingly, my script doesn't really see the
output as its emitted, so the timestamp line it prepends to a block of
output is off.

I'm currently using subprocess.Popen like so:

    os.environ["TERM"] = "dumb"
    cmd = "prstat -c %s" % " ".join(sys.argv[1:])
    pipe = Popen(cmd, shell=True, bufsize=1, stdout=PIPE).stdout

I've tried these other variants as well:

  * prefacing the prstat command with unbuffer (the tcl/expect thingamabob)

  * explicitly redirect the prstat output to /dev/stdout

  * setting bufsize to 0

  * used os.popen instead of Subprocess.Popen

Nothing seems to help.  I always seem to see about 30 seconds of data at
once (I'm currently using a 5-second interval and 10 lines of output).  I
would have expected that prstat would simply flush stdout after each block
of output.

Any ideas about how to get prstat to cooperate better?

Thanks,

-- 
Skip Montanaro - skip at pobox.com - http://www.smontanaro.net/
    That's more than a dress. That's an Audrey Hepburn movie. -- Jerry Maguire


From simon at brunningonline.net  Mon Jul 27 10:31:11 2009
From: simon at brunningonline.net (Simon Brunning)
Date: Mon, 27 Jul 2009 15:31:11 +0100
Subject: iText for Python
In-Reply-To: <505f2bc1-cbfb-49a1-a7ef-0b6c357750a7@q35g2000vbi.googlegroups.com>
References: <505f2bc1-cbfb-49a1-a7ef-0b6c357750a7@q35g2000vbi.googlegroups.com>
Message-ID: <8c7f10c60907270731x1d416e64vde1907d8c4dd42d1@mail.gmail.com>

2009/7/27 santhoshvkumar <santhosh.vkumar at gmail.com>:
> ? ? ? ? ? One of my cousin ?suggested me to do a IText PDF converter
> for python. Actually I heard that there is no separate IText converter
> either we have to go for jython or GCJ with wrapper. Instead of
> wrapping, my plan is to create a separate module with Python and I am
> thinking of doing this in as my final year project also. Kindly give
> me your suggestion.

What would this give us that ReportLab does not? I wouldn't want to
see you spend a lot of time reinventing the wheel...

-- 
Cheers,
Simon B.


From aahz at pythoncraft.com  Mon Jul 27 10:32:53 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:32:53 -0700
Subject: Form/Template Fill-in the blanks
References: <4b77a992-370d-4879-88a0-fdd6a23f7c5d@p10g2000prm.googlegroups.com>
Message-ID: <h4kdql$b4a$1@panix3.panix.com>

In article <4b77a992-370d-4879-88a0-fdd6a23f7c5d at p10g2000prm.googlegroups.com>,
allan  <kawenks at gmail.com> wrote:
>
>My initial thought was to use:
>1. .ini files to declare the EDI configuration
>
>INI file configuration:
>* A "root" INI file indicates other INI files that define each segment
>of the EDI document.
>* Each segment INI defines the data elements of each segment and the
>behavior of the segment (one instance or multiple-instance as in a
>loop, sequence order, segment code, etc.)
>* Specify data elements as either constant, system function (like
>datetime), database field or object method (object being the
>segment's)
>* Load all the ini configuration into a "template" object. Each
>segment ini maps to its own segment object.

This sounds like something you want to use XML for.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From bryanvick at gmail.com  Mon Jul 27 10:37:53 2009
From: bryanvick at gmail.com (Bryan)
Date: Mon, 27 Jul 2009 07:37:53 -0700 (PDT)
Subject: Script runs manually, but cron fails
References: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
Message-ID: <ffa9d698-f620-4db1-aebc-eff7c930b983@e27g2000yqm.googlegroups.com>

On Jul 24, 2:11?pm, Bryan <bryanv... at gmail.com> wrote:
> I have a backup script that runs fine when I run it manually from the
> command line. ?When I run it with cron, the script stops running at
> random points in the source code.
>
> The script calls rsync with the subprocess module, which in turn uses
> ssh to backup files from a box on my lan. ?It also uses the atexit
> module to always run a certain piece of cleanup code when the script
> exits. ?However, this piece of code is never called when I use cron to
> run the script, but a ps -A command also does not show the python
> process so I know the script is dead. ?The log files generated by the
> script all show rsync as completing, but then the logging gets cutoff
> at random places when the script dies after that point. ?I am not
> getting any email from cron complaining of an error either.
>
> The script runs fine in my bash shell, what could cron be doing to
> interfere?

This script works when I run it at home, and I think it is because I
don't use rsync's ability to backup over ssh.  The working script at
home simply backs up the local machine to a mounted external hard
drive.  So when I run a python script that calls rsync to work over
ssh, cron is screwing things up.  Can anyone recommend where I should
report this behavior?  Should I email the author of cron directly, I
don't see a group/address specifically for cron bugs.


From kushal.kumaran+python at gmail.com  Mon Jul 27 10:40:40 2009
From: kushal.kumaran+python at gmail.com (Kushal Kumaran)
Date: Mon, 27 Jul 2009 20:10:40 +0530
Subject: Itext for Python
In-Reply-To: <b423b9550907270153v5b21cb35wc3741c8d5775e574@mail.gmail.com>
References: <404c076d0907261122r35a1cca9kf11940d972d2b691@mail.gmail.com> 
	<b423b9550907270153v5b21cb35wc3741c8d5775e574@mail.gmail.com>
Message-ID: <1e364c4e0907270740sdc0e6ceye49f78b342820096@mail.gmail.com>

On Mon, Jul 27, 2009 at 2:23 PM, S.Selvam<s.selvamsiva at gmail.com> wrote:
>
>
> On Sun, Jul 26, 2009 at 11:52 PM, Santhosh Kumar <santhosh.vkumar at gmail.com>
> wrote:
>>
>> Hi all,
>> ?? ? ? ? ??One of my cousin ?suggested me to do a IText PDF?converter?for
>> python. Actually I heard that there is no?separate?IText?converter?either we
>> have to go for jython or GCJ with wrapper. Instead of wrapping, my plan is
>> to?create a separate module with Python and I am thinking of doing this in
>> as my final year project also. Kindly give me your?suggestion.
>
> As for as i know, no pure python module exists for iText PDF generator,
> where iText seems to be a standard one for PDF related works.There are some
> other modules for pdf work but might not be as standard as iText.Surely some
> senior programmers? will suggest you better way to proceed further.
>

AFAIK, iText is just a java library for generating PDF files.  You
could have a look at http://www.reportlab.org/rl_toolkit.html

-- 
kushal


From james at agentultra.com  Mon Jul 27 10:40:53 2009
From: james at agentultra.com (J Kenneth King)
Date: Mon, 27 Jul 2009 10:40:53 -0400
Subject: Script runs manually, but cron fails
References: <4cba6362-a25c-4bf1-b27b-4ddf48feb473@d9g2000prh.googlegroups.com>
Message-ID: <858wia6vey.fsf@agentultra.com>

Bryan <bryanvick at gmail.com> writes:

> I have a backup script that runs fine when I run it manually from the
> command line.  When I run it with cron, the script stops running at
> random points in the source code.
>
> The script calls rsync with the subprocess module, which in turn uses
> ssh to backup files from a box on my lan.  It also uses the atexit
> module to always run a certain piece of cleanup code when the script
> exits.  However, this piece of code is never called when I use cron to
> run the script, but a ps -A command also does not show the python
> process so I know the script is dead.  The log files generated by the
> script all show rsync as completing, but then the logging gets cutoff
> at random places when the script dies after that point.  I am not
> getting any email from cron complaining of an error either.
>
> The script runs fine in my bash shell, what could cron be doing to
> interfere?

Double check nothing is writing to stdout/stdin

Some cron's don't mind, but I always squelch output because some do.


From aahz at pythoncraft.com  Mon Jul 27 10:41:45 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:41:45 -0700
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<2a408da6-af57-45d0-a75f-4cbe384bb7f9@s15g2000yqs.googlegroups.com>
	<h4iqgb$ss5$1@panix3.panix.com>
	<1c8ae01e-2e9c-497c-9f8d-408f56f9c0bd@g31g2000yqc.googlegroups.com>
Message-ID: <h4keb9$ita$1@panix3.panix.com>

In article <1c8ae01e-2e9c-497c-9f8d-408f56f9c0bd at g31g2000yqc.googlegroups.com>,
Michal Kwiatkowski  <constant.beta at gmail.com> wrote:
>On Jul 27, 1:56 am, a... at pythoncraft.com (Aahz) wrote:
>>>> Upon a cursory look, after a generator 'gen' is exhausted (meaning
>>>> gen.next() has raised StopIteration), it seems that gen.gi_frame will be
>>>> None.
>>>
>>>Only in Python 2.5 or higher though. I need to support Python 2.3 and
>>>2.4 as well, sorry for not making that clear in the original post.
>>
>> Are you sure?  It appears to work in Python 2.4; I don't have time to
>> check 2.3.
>
>No, it does not work in Python 2.4. gi_frame can be None only in
>Python 2.5 and higher.

You're right, I guess I must have made a boo-boo when I was switching
versions.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From aahz at pythoncraft.com  Mon Jul 27 10:45:50 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:45:50 -0700
Subject: pyc files not automatically compiled on import
References: <mailman.3739.1248625343.8015.python-list@python.org>
Message-ID: <h4keiu$au1$1@panix3.panix.com>

In article <mailman.3739.1248625343.8015.python-list at python.org>,
Baz Walter  <bazwal at ftml.net> wrote:
>
>i thought that python automatically compiled pyc files after a module is 
>successfully imported. what could prevent this happening?

Looks like you got your problem fixed, but for the record, not having
write permission on a directory also causes this.  It's even uglier when
the .pyc already exists but does not have write perms.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From aahz at pythoncraft.com  Mon Jul 27 10:49:25 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 07:49:25 -0700
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
Message-ID: <h4kepl$qhf$1@panix3.panix.com>

In article <mailman.3765.1248685391.8015.python-list at python.org>,
Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>
>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>
>I have searched, but I can find nothing about this mediocre language.
>
>Could you tell us more?

:-P

(For anyone who is confused by Hendrik's humor, he is saying that David
was referring to a programming language named "mediocre".  English
grammar is confusing!)
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From ethan at stoneleaf.us  Mon Jul 27 11:00:12 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Mon, 27 Jul 2009 08:00:12 -0700
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <468250.83203.qm@web31106.mail.mud.yahoo.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
Message-ID: <4A6DC0FC.90704@stoneleaf.us>

[corrected top posting]

Mohammad Tayseer wrote:
>> *From:* Piet van Oostrum <piet at cs.uu.nl>
>> *To:* python-list at python.org
>> *Sent:* Monday, July 27, 2009 11:18:20 AM
>> *Subject:* Re: Looking for a dream language: sounds like Python to me.
>> 
>>  >>>>> Dotan Cohen <dotancohen at gmail.com <mailto:dotancohen at gmail.com>> 
>> (DC) wrote:
>> 
>>  >DC> Referring to this article:
>>>DC> 
>> http://math-blog.com/2009/07/20/complex-algorithm-research-and-development-harder-than-many-think/
>> 
>>  >DC> The author, who is specifically looking for math-related 
>> functions, writes:
>>  >DC> """
>>  >DC> The dream algorithm R&D tool would be similar to Matlab or Mathematica
>>  >DC> but could be compiled to fast, efficient binaries similar to ANSI C
>>  >DC> and would be available for all platforms. An integrated GUI builder
>>  >DC> similar to Visual Basic and integrated network support would be
>>  >DC> helpful.
>>  >DC> """
>> 
>>  >DC> It looks to me like he is looking for Python.
>> 
>> No fast, efficient binaries yet, and no integrated GUI builder.
>> -- 
>> Piet van Oostrum <piet at cs.uu.nl <mailto:piet at cs.uu.nl>>
>> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
>> Private email: piet at vanoostrum.org <mailto:piet at vanoostrum.org>
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
>> 
 > You can generate binaries using py2exe, and you can create UI using
 > Tkinter (which is very easy) or wxPython (which have GUI builders)
 >
 > Mohammad Tayseer
 > http://spellcoder.com/blogs/tayseer

Creating binaries is not the same as creating /fast, efficient/ 
binaries.  Py2Exe bundles it all together, but does not make it any faster.

~Ethan~


From __peter__ at web.de  Mon Jul 27 11:12:02 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 17:12:02 +0200
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
	<h4k9e6$tf9$02$1@news.t-online.com>
	<8b78b47f-799e-4d37-bc28-d1ed349362c9@k6g2000yqn.googlegroups.com>
Message-ID: <h4kg42$fit$01$1@news.t-online.com>

Martin wrote:

> The statement works now, but it doesn't give the same results as my
> original logic, strangely!?
> 
> in my logic:
> 
> data = np.zeros((numrows, numcols), dtype = np.uint8, order ='C')
> 
> for i in range(numrows):
>     for j in range(numcols):
>         if band3[i,j] == 255 or band3[i,j] >= band6[i,j] * factor:
>             data[i,j] = 0
>         else:
>             data[i,j] = 1
> 
> to do the same with what you suggested...
> 
> data = np.ones((numrows, numcols), dtype = np.uint8, order ='C')
> data[(band3 == 255) | (band6 >= band3 * factor)] = 0

Did you swap band3 and band6? If that's the case, it is an error you should 
be able to find yourself.

Please be a bit more careful.

Also, it is good practice to write a few test cases where you have 
precalculated the result. How would you otherwise know which version is 
correct? Writing a third one to break the tie?

Peter




From dotancohen at gmail.com  Mon Jul 27 11:12:09 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Mon, 27 Jul 2009 18:12:09 +0300
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <4A6DC0FC.90704@stoneleaf.us>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
Message-ID: <880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>

> Creating binaries is not the same as creating /fast, efficient/ binaries.
> ?Py2Exe bundles it all together, but does not make it any faster.
>

How inefficient is py2exe. I was under the impression that it's really
not that bad.

-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From dns4 at cornell.edu  Mon Jul 27 11:14:15 2009
From: dns4 at cornell.edu (David Smith)
Date: Mon, 27 Jul 2009 11:14:15 -0400
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4kepl$qhf$1@panix3.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
Message-ID: <h4kg88$6s6$1@ruby.cit.cornell.edu>

Aahz wrote:
> In article <mailman.3765.1248685391.8015.python-list at python.org>,
> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>> I have searched, but I can find nothing about this mediocre language.
>>
>> Could you tell us more?
> 
> :-P
> 
> (For anyone who is confused by Hendrik's humor, he is saying that David
> was referring to a programming language named "mediocre".  English
> grammar is confusing!)

LOL ... I'm an American and that wasn't all that clear :-)


From exarkun at divmod.com  Mon Jul 27 11:18:41 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Mon, 27 Jul 2009 11:18:41 -0400
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
Message-ID: <20090727151841.388.143506053.divmod.quotient.793@henry.divmod.com>

On Mon, 27 Jul 2009 18:12:09 +0300, Dotan Cohen <dotancohen at gmail.com> wrote:
>> Creating binaries is not the same as creating /fast, efficient/ binaries.
>> ?Py2Exe bundles it all together, but does not make it any faster.
>>
>
>How inefficient is py2exe. I was under the impression that it's really
>not that bad.
>

py2exe doesn't really change the performance characteristics of a Python
application at all - for better or for worse.

Jean-Paul


From gmweezel at gmail.com  Mon Jul 27 11:21:29 2009
From: gmweezel at gmail.com (Eric)
Date: Mon, 27 Jul 2009 08:21:29 -0700 (PDT)
Subject: CRLF Newlines and libc
Message-ID: <6bcb4820-11be-4053-8e3b-849b00aba55a@c2g2000yqi.googlegroups.com>

I am working on the subprocess.Popen module for Google Summer of Code.
Right now, I am having difficulty trying to work out how to deal with
my '\n' newlines being converted to '\r\n' newlines when reading from
a pipe on windows; see this blog post (http://subdev.blogspot.com/
2009/07/stdout.html) and this chain on Python-Dev (http://
mail.python.org/pipermail/python-dev/2009-July/090720.html).

Right now, unless there is way to disable the newline conversions, I
am thinking I will just have to document the caveat and call it a day.
Is there a better way to handle this?

Eric


From cournape at gmail.com  Mon Jul 27 11:22:16 2009
From: cournape at gmail.com (David Cournapeau)
Date: Tue, 28 Jul 2009 00:22:16 +0900
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
Message-ID: <5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>

On Tue, Jul 28, 2009 at 12:12 AM, Dotan Cohen<dotancohen at gmail.com> wrote:
>> Creating binaries is not the same as creating /fast, efficient/ binaries.
>> ?Py2Exe bundles it all together, but does not make it any faster.
>>
>
> How inefficient is py2exe.

It is neither efficient or inefficient: it is just a distribution
tool, to deploy python software in a form familiar to most windows
users. It does not make it any faster than running the software under
a python prompt.

As much as I like python for scientific programming, I would say
python is pretty far from the stated requirements in the posted blog
post. It is difficult to deploy software written with python (much
better than the alternatives, though), and it is slow if you can't
leverage numpy/scipy (where vectorization does not apply).

It remains to be seen whether it will be true in practice, but
something like F#, with its integration in VS 2010, seems much closer
IMHO. It is compiled, high level language, and backed by the biggest
software vendor in the world.

David


From invalid at invalid  Mon Jul 27 11:24:27 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 27 Jul 2009 10:24:27 -0500
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl> <468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<mailman.3780.1248707531.8015.python-list@python.org>
Message-ID: <KtadnYzrE7w2W_DXnZ2dnUVZ_jhi4p2d@posted.visi>

On 2009-07-27, Dotan Cohen <dotancohen at gmail.com> wrote:
>> Creating binaries is not the same as creating /fast, efficient/ binaries.
>> ??Py2Exe bundles it all together, but does not make it any faster.
>
> How inefficient is py2exe.

[Assuming that was a question.]

py2exe just bundles up the files needed to run the program.
The result runs pretty much the same as it did when it was
"unbundled".  By default, py2exe combines some stuff in a zip
file, so that might slow down startup by a tiny amount. If
you don't like that, you can tell py2exe not to "zip" things
up, and then the program runs pretty much identically as did
the unbundled version.

> I was under the impression that it's really not that bad.

py2exe doesn't really have any impact on the program's
perfromance.  It's still the same Python VM running the same
bytecode using the same library files.

-- 
Grant Edwards                   grante             Yow! I'm totally DESPONDENT
                                  at               over the LIBYAN situation
                               visi.com            and the price of CHICKEN
                                                   ...


From dotancohen at gmail.com  Mon Jul 27 11:28:47 2009
From: dotancohen at gmail.com (Dotan Cohen)
Date: Mon, 27 Jul 2009 18:28:47 +0300
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
Message-ID: <880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>

> It is neither efficient or inefficient: it is just a distribution
> tool, to deploy python software in a form familiar to most windows
> users. It does not make it any faster than running the software under
> a python prompt.
>
> As much as I like python for scientific programming, I would say
> python is pretty far from the stated requirements in the posted blog
> post. It is difficult to deploy software written with python (much
> better than the alternatives, though), and it is slow if you can't
> leverage numpy/scipy (where vectorization does not apply).
>
> It remains to be seen whether it will be true in practice, but
> something like F#, with its integration in VS 2010, seems much closer
> IMHO. It is compiled, high level language, and backed by the biggest
> software vendor in the world.
>

The blog post is not looking to distribute his code, but he would like
it to be cross platform for his own reasons. VB is not cross platform.


-- 
Dotan Cohen

http://what-is-what.com
http://gibberish.co.il


From cournape at gmail.com  Mon Jul 27 11:39:14 2009
From: cournape at gmail.com (David Cournapeau)
Date: Tue, 28 Jul 2009 00:39:14 +0900
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>
Message-ID: <5b8d13220907270839p3f65e1f8k7c1bb022bc922d6e@mail.gmail.com>

On Tue, Jul 28, 2009 at 12:28 AM, Dotan Cohen<dotancohen at gmail.com> wrote:
>> It is neither efficient or inefficient: it is just a distribution
>> tool, to deploy python software in a form familiar to most windows
>> users. It does not make it any faster than running the software under
>> a python prompt.
>>
>> As much as I like python for scientific programming, I would say
>> python is pretty far from the stated requirements in the posted blog
>> post. It is difficult to deploy software written with python (much
>> better than the alternatives, though), and it is slow if you can't
>> leverage numpy/scipy (where vectorization does not apply).
>>
>> It remains to be seen whether it will be true in practice, but
>> something like F#, with its integration in VS 2010, seems much closer
>> IMHO. It is compiled, high level language, and backed by the biggest
>> software vendor in the world.
>>
>
> The blog post is not looking to distribute his code, but he would like
> it to be cross platform for his own reasons. VB is not cross platform.

I understand his "efficient binary as Ansi C" partially as a
deployment requirement, and independent of cross-platform issues. As a
scientist, being able to share my software with colleagues is a non
trivial matter. Python does not make this easy today.

F# has nothing to do with VB: F# is a ML-language inspired from OCAML,
and run on top of the CLR. It can thus leverage the huge .net
framework (lack of non numerical API is one of the biggest matlab
hindrance, and comparatively big advantage of python + numpy/scipy),
and benefits from the much more efficient implementation compared to
python (under the currently CPython implementation at least).

Some recent F# versions are compatible with mono, making it compatible
on most platforms that matter today for research (but of course, you
lose the IDE integration outside windows).

David


From jakecjacobson at gmail.com  Mon Jul 27 11:44:40 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Mon, 27 Jul 2009 08:44:40 -0700 (PDT)
Subject: exceptions.TypeError an integer is required
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
	<0279f85d$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <8d03a739-7e45-49e1-b93d-6a396beed877@a37g2000prf.googlegroups.com>

On Jul 24, 3:11?pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Fri, 24 Jul 2009 11:24:58 -0700, jakecjacobson wrote:
> > I am trying to do a post to a REST API over HTTPS and requires the
> > script to pass a cert to the server. ?I am getting "exceptions.TypeError
> > an integer is required" error and can't find the reason. ?I commenting
> > out the lines of code, it is happening on the connection.request() line.
> > ?Here is the problem code. ?Would love some help if possible.
>
> Please post the traceback that you get.
>
> My guess is that you are passing a string instead of an integer, probably
> for the port.
>
> [...]
>
> > ? ?except:
> > ? ? ? ? ? ?print sys.exc_type, sys.exc_value
>
> As a general rule, a bare except of that fashion is bad practice. Unless
> you can explain why it is normally bad practice, *and* why your case is
> an exception (no pun intended) to the rule "never use bare except
> clauses", I suggest you either:
>
> * replace "except:" with "except Exception:" instead.
>
> * better still, re-write the entire try block as:
>
> ? ? try:
> ? ? ? ? [code goes here]
> ? ? finally:
> ? ? ? ? connection.close()
>
> and use the Python error-reporting mechanism instead of defeating it.
>
> --
> Steven

Steven,

You are quite correct in your statements.  My goal was not to make
great code but something that I could quickly test.  My assumption was
that the httplib.HTTPSConnection() would do the cast to int for me.
As soon as I cast it to an int, I was able to get past that issue.

Still not able to post because I am getting a bad cert error.

Jake Jacobson


From jakecjacobson at gmail.com  Mon Jul 27 11:57:40 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Mon, 27 Jul 2009 08:57:40 -0700 (PDT)
Subject: bad certificate error
Message-ID: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>

Hi,

I am getting the following error when doing a post to REST API,

Enter PEM pass phrase:
Traceback (most recent call last):
  File "./ices_catalog_feeder.py", line 193, in ?
    main(sys.argv[1])
  File "./ices_catalog_feeder.py", line 60, in main
    post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
(input_dir, file), collection_name, key_file, cert_file)
  File "./ices_catalog_feeder.py", line 125, in post2Catalog
    connection.request('POST', path, parameters, head)
  File "/usr/lib/python2.4/httplib.py", line 810, in request
    self._send_request(method, url, body, headers)
  File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
    self.endheaders()
  File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
    self._send_output()
  File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
    self.send(msg)
  File "/usr/lib/python2.4/httplib.py", line 652, in send
    self.connect()
  File "/usr/lib/python2.4/httplib.py", line 1079, in connect
    ssl = socket.ssl(sock, self.key_file, self.cert_file)
  File "/usr/lib/python2.4/socket.py", line 74, in ssl
    return _realssl(sock, keyfile, certfile)
socket.sslerror: (1, 'error:14094412:SSL
routines:SSL3_READ_BYTES:sslv3 alert bad certificate')


My code where this error occurs is:

head = {"Content-Type" : "application/x-www-form-urlencoded",
"Accept" : "text/plain"}
parameters = urlencode({"collection" : collection, "entryxml" : open
(file,'r').read()})
print "Sending the file to: " + host

try:
	try:
		# Default port is 443.
		# key_file is the name of a PEM formatted file that contains your
private key.
		# cert_file is a PEM formatted certificate chain file.
		connection = httplib.HTTPSConnection(host, int(port), key_file,
cert_file)
		connection.request('POST', path, parameters, head)
		response = connection.getresponse()
		print response.status, response.reason
	except httplib.error, (value,message):
		print value + ':' + message
finally:
	connection.close()

I was wondering if this is due to the server having a invalid server
cert?  If I go to this server in my browser, I get a "This server
tried to identify itself with invalid information".  Is there a way to
ignore this issue with Python?  Can I setup a trust store and add this
server to the trust store?


From mdekauwe at gmail.com  Mon Jul 27 12:00:41 2009
From: mdekauwe at gmail.com (Martin)
Date: Mon, 27 Jul 2009 09:00:41 -0700 (PDT)
Subject: quickly looping over a 2D array?
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
	<h4k3ro$719$00$1@news.t-online.com>
	<503adfe2-bf70-422e-b22f-8befcae577b9@r2g2000yqm.googlegroups.com>
	<h4k7jt$ec1$00$1@news.t-online.com>
	<266d5f19-6a9d-4733-9cd4-f40f03dcb1fa@k1g2000yqf.googlegroups.com>
	<h4k9e6$tf9$02$1@news.t-online.com>
	<8b78b47f-799e-4d37-bc28-d1ed349362c9@k6g2000yqn.googlegroups.com>
	<h4kg42$fit$01$1@news.t-online.com>
Message-ID: <f0ead2ff-c7a3-4271-8311-049db3d203e9@c29g2000yqd.googlegroups.com>

On Jul 27, 4:12 pm, Peter Otten <__pete... at web.de> wrote:
> Martin wrote:
> > The statement works now, but it doesn't give the same results as my
> > original logic, strangely!?
>
> > in my logic:
>
> > data = np.zeros((numrows, numcols), dtype = np.uint8, order ='C')
>
> > for i in range(numrows):
> >     for j in range(numcols):
> >         if band3[i,j] == 255 or band3[i,j] >= band6[i,j] * factor:
> >             data[i,j] = 0
> >         else:
> >             data[i,j] = 1
>
> > to do the same with what you suggested...
>
> > data = np.ones((numrows, numcols), dtype = np.uint8, order ='C')
> > data[(band3 == 255) | (band6 >= band3 * factor)] = 0
>
> Did you swap band3 and band6? If that's the case, it is an error you should
> be able to find yourself.
>
> Please be a bit more careful.
>
> Also, it is good practice to write a few test cases where you have
> precalculated the result. How would you otherwise know which version is
> correct? Writing a third one to break the tie?
>
> Peter

apologies... it was the way I typed it up, I wasn't copying and
pasting from my text editor!
Thanks Peter.


From davea at ieee.org  Mon Jul 27 12:09:38 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 12:09:38 -0400
Subject: [python-win32] subprocess and stdout
In-Reply-To: <BAY112-W553A4383329E89926BF75F7140@phx.gbl>
References: <BAY112-DS5EA522027B7C10D4AC9C8F7170@phx.gbl>
	<4A6D9D83.6050505@ieee.org>
	<BAY112-W553A4383329E89926BF75F7140@phx.gbl>
Message-ID: <4A6DD142.7040809@ieee.org>

(This message was top-posted, and sent off-list.  So I'm copying it back 
to the list, with my response at the end)

Chris Chapman wrote:
> Thanks Dave.  You know after trying your suggestion on the command prompt it doesn't as a matter of fact.  Not sure why I didn't just try that in windows to begin with.  Guess I got stuck more on the python issue then it being the other program.
>
> There is an option for it to create an HTML log file, but it's formatted sort of strangely.  I'm really not looking to parse through it just for a summary like that presented on the terminal.  I'm not sure if you know but I'm guessing parsing the HTML would be a lot easier the trying to capture the console output from the buffer, huh?  Thanks again for the help.
>
> Chris
>
>   
>> Date: Mon, 27 Jul 2009 08:28:51 -0400
>> From: davea at ieee.org
>> To: oxydol010 at hotmail.com
>> CC: python-win32 at python.org
>> Subject: Re: [python-win32] subprocess and stdout
>>
>> Christopher Chapman wrote:
>>     
>>> I'm trying to write a "module" to a larger program.  This module eventually
>>> needs to reference a config file with setup information in it, but I'm not
>>> there yet.  I'm using the subprocess module to run an external antivirus
>>> program and trying to get the output written to a log file, but I keep
>>> getting a weird return.  My code is listed below.  I'm a noob to Python so
>>> I'm not sure if this is a windows specific issue or not, but I'm programming
>>> on windows and more then likely what I'm working on won't be on anything
>>> other then a windows machine.  I'm also writing my code for 3.1 if that
>>> makes any difference.
>>>
>>> # Pass target path to scanners command line and write output to a file
>>> # Currently "scan" only targets the McAfee Command Line Scanner
>>> print() 
>>> print ("Begining scan of " + target)
>>> print()
>>> scan = "scan /all " + target
>>> s = subprocess.Popen(scan,
>>>                      stdout=subprocess.PIPE)
>>> out = s.communicate()[0]
>>> chgout = str(out)
>>> s.wait()
>>> scanlog.write(chgout)
>>> scanlog.close
>>> "
>>> If I change my stdout in s subprocess to None then everything gets written
>>> to the terminal as if I had just run the program straight from the command
>>> line, but when I try piping it to my file "scanlog" then literally the only
>>> return I get in the file is '' or two single quotes.  I've even tried piping
>>> the output and then printing it instead of writing it to a file and I get
>>> the same result.  I've experimented with standard windows command line
>>> commands and using the same syntax was able to pipe directory listings and
>>> other things to my file.  Any ideas what I'm missing here?  Thanks in
>>> advance
>>>
>>> Chris Chapman
>>>
>>>
>>>   
>>>       
>> I suspect it's because of the way the antivirus program is written.  I 
>> can't be sure what you tried at the command prompt, but have you tried this:
>>
>> c:\>scan /all > scanlog.txt
>>
>>
>> If this does not capture to the file, then scan.exe isn't written in the 
>> way you're expecting.  There are several ways to write directly to a 
>> console that do not redirect or pipe.
>>
>> You might also look to see whether scan has any other commandline 
>> options.  One of them might be to create a log file.
>>
>> DaveA
>>     
>
>   

I wouldn't know where to begin trying to capture output that another 
process sends to its console window.  While I'm sure it's possible, I do 
suspect that parsing the html would be easier.  Remember that even if it 
looks ugly, it is generated by program, and it's quite possible that you 
could throw away the fluff and end up with a simple summary.  There are 
libraries to make this easier, but I've never used them.  If it's valid 
xhtml, which is by definition valid xml, you might find it useful to use 
elementree.  But most html is buggy, and parsing that takes a more 
tolerant parser.

DaveA



From robert.kern at gmail.com  Mon Jul 27 12:11:02 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Mon, 27 Jul 2009 11:11:02 -0500
Subject: quickly looping over a 2D array?
In-Reply-To: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
References: <1b8747d1-571a-4d79-8849-b918fefeaf4d@r2g2000yqm.googlegroups.com>
Message-ID: <h4kjim$mgj$1@ger.gmane.org>

On 2009-07-27 06:24, Martin wrote:
> Hi,
>
> I am new to python and I was wondering if there was a way to speed up
> the way I index 2D arrays when I need to check two arrays
> simultaneously? My current implementations is (using numpy) something
> like the following...
>
> for i in range(numrows):
>      for j in range(numcols):
>
>          if array_1[i, j] == some_value or array_2[i, j]>= array_1[i,
> j] * some_other_value
>              array_1[i, j] = some_new_value

Peter has given you good answers, but you will probably want to ask future numpy 
questions on the numpy mailing list.

   http://www.scipy.org/Mailing_Lists

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From python at mrabarnett.plus.com  Mon Jul 27 12:34:03 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 27 Jul 2009 17:34:03 +0100
Subject: New implementation of re module
Message-ID: <4A6DD6FB.8040609@mrabarnett.plus.com>

Hi all,

I've been working on a new implementation of the re module. The details
are at http://bugs.python.org/issue2636, specifically from
http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
Python 2.6 on Windows if you want to try it out.

I'm interested in how fast it is generally, compared with the current re
module, but especially when faced with those 'pathological' regular
expressions which seem to take a long time to finish, for example:

     re.search(r"^(.+|D)*A$", "x" * 25 + "B")

which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs 
with this new implementation.

TIA


From Ray.Joseph at CDICorp.com  Mon Jul 27 12:42:06 2009
From: Ray.Joseph at CDICorp.com (ray)
Date: Mon, 27 Jul 2009 09:42:06 -0700 (PDT)
Subject: Using easy_install, reduncant?
Message-ID: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>

I am working on a Trac installation.  I am new to Python.  To install
packages, it is suggested to use setuptools.  I have not understood
the directions.

I execute ez_install.py.

Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
There response that setuptools is already the active version in easy-
install.pth.  Then:
Installing easy_install.exe script to C:\Python26\Scripts error:  C:
\Python26\Scripts\Easy_install.exe: Permission denied.

I have compared the file entries before and after this attempt and
there are no new files.  Is there any problems here?  What did I miss?

Regards,
Ray


From nagle at animats.com  Mon Jul 27 12:58:57 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 09:58:57 -0700
Subject: Using easy_install, reduncant?
In-Reply-To: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
References: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
Message-ID: <4a6ddc22$0$1667$742ec2ed@news.sonic.net>

ray wrote:
> I am working on a Trac installation.  I am new to Python.  To install
> packages, it is suggested to use setuptools.  I have not understood
> the directions.
> 
> I execute ez_install.py.
> 
> Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
> There response that setuptools is already the active version in easy-
> install.pth.  Then:
> Installing easy_install.exe script to C:\Python26\Scripts error:  C:
> \Python26\Scripts\Easy_install.exe: Permission denied.

    "Easy Install" usually isn't "easy".  If it works, it's great.
Most of the time, it doesn't.  It's not very good at finding all the
files it needs to update.  Hence problems like the above.

				John Nagle


From deets at nospam.web.de  Mon Jul 27 13:00:52 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 19:00:52 +0200
Subject: Using easy_install, reduncant?
References: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
	<4a6ddc22$0$1667$742ec2ed@news.sonic.net>
Message-ID: <7d64q4F2an2drU1@mid.uni-berlin.de>

John Nagle wrote:

> ray wrote:
>> I am working on a Trac installation.  I am new to Python.  To install
>> packages, it is suggested to use setuptools.  I have not understood
>> the directions.
>> 
>> I execute ez_install.py.
>> 
>> Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
>> There response that setuptools is already the active version in easy-
>> install.pth.  Then:
>> Installing easy_install.exe script to C:\Python26\Scripts error:  C:
>> \Python26\Scripts\Easy_install.exe: Permission denied.
> 
>     "Easy Install" usually isn't "easy".  If it works, it's great.
> Most of the time, it doesn't.  It's not very good at finding all the
> files it needs to update.  Hence problems like the above.

Which is the usual BS from you. It works most of the times as advertised,
and in the concrete case the OP misunderstood what ez_setup.py does
(already installing setuptools), and thus the complaint about "already
active version". Which btw is just a warning, and setuptools would
continue, but as the OP works on Windows which prohibits a running
executable to be replaced, it fails. Again, not setuptools fault.

Diez


From nagle at animats.com  Mon Jul 27 13:23:43 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 10:23:43 -0700
Subject: M2Crypto hangs on this URL
Message-ID: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>

There's something strange about this URL:

"https://sagar310.pontins.com/sraep/"

It hangs Firefox 2; there's no short timeout, the web page just gets
stuck in initial load for about ten minutes.  Then
"The connection to sagar310.pontins.com was interrupted while the page was loading."

It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.

What does the new SSL implementation do?  (Haven't tried that yet;
waiting for MySQL support for Python 3.x before converting web apps.)

				John Nagle


From rlichlighter at gmail.com  Mon Jul 27 13:25:18 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 10:25:18 -0700 (PDT)
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<h4k8o8$ght$00$1@news.t-online.com>
Message-ID: <bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>

On Jul 27, 9:06?am, Peter Otten <__pete... at web.de> wrote:
> r2 wrote:
> > I have a memory dump from a machine I am trying to analyze. I can view
> > the file in a hex editor to see text strings in the binary code. I
> > don't see a way to save these ascii representations of the binary, so
> > I went digging into Python to see if there were any modules to help.
>
> > I found one I think might do what I want it to do - the binascii
> > module. Can anyone describe to me how to convert a raw binary file to
> > an ascii file using this module. I've tried? Boy, I've tried.
>
> That won't work because a text editor doesn't need any help to convert the
> bytes into characters. If it expects ascii it just will be puzzled by bytes
> that are not valid ascii. Also, it will happily display byte sequences that
> are valid ascii, but that you as a user will see as gibberish because they
> were meant to be binary data by the program that wrote them.
>
> > Am I correct in assuming I can get the converted binary to ascii text
> > I see in a hex editor using this module? I'm new to this forensics
> > thing and it's quite possible I am mixing technical terms. I am not
> > new to Python, however. Thanks for your help.
>
> Unix has the "strings" commandline tool to extract text from a binary.
> Get hold of a copy of the MinGW tools if you are on windows.
>
> Peter

Okay. Thanks for the guidance. I have a machine with Linux, so I
should be able to do what you describe above. Could Python extract the
strings from the binary as well? Just wondering.


From rlichlighter at gmail.com  Mon Jul 27 13:25:44 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 10:25:44 -0700 (PDT)
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>
Message-ID: <fb63e796-f92f-4436-b6bd-da91ca7989ce@n11g2000yqb.googlegroups.com>

On Jul 27, 10:11?am, Grant Edwards <invalid at invalid> wrote:
> On 2009-07-27, r2 <rlichligh... at gmail.com> wrote:
>
> > I have a memory dump from a machine I am trying to analyze. I can view
> > the file in a hex editor to see text strings in the binary code. I
> > don't see a way to save these ascii representations of the binary,
>
> $ strings memdump.binary >memdump.strings
>
> $ hexdump -C memdump.binary >memdump.hex+ascii
>
> --
> Grant Edwards ? ? ? ? ? ? ? ? ? grante ? ? ? ? ? ? Yow! I'm ZIPPY the PINHEAD
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? at ? ? ? ? ? ? ? and I'm totally committed
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?visi.com ? ? ? ? ? ?to the festive mode.

Grant,

Thanks for the commands!


From reckoner at gmail.com  Mon Jul 27 13:40:03 2009
From: reckoner at gmail.com (Reckoner)
Date: Mon, 27 Jul 2009 10:40:03 -0700 (PDT)
Subject: initializing with empty list as default causes freaky problems
Message-ID: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>

Hi,

Observe the following:

In [202]: class Foo():
   .....:     def __init__(self,h=[]):
   .....:         self.h=h
   .....:
   .....:

In [203]: f=Foo()

In [204]: g=Foo()

In [205]: g.h
Out[205]: []

In [206]: f.h
Out[206]: []

In [207]: f.h.append(10)

In [208]: f.h
Out[208]: [10]

In [209]: g.h
Out[209]: [10]

The question is: why is g.h updated when I append to f.h?  Shouldn't
g.h stay []?

What am I missing here?

I'm using Python 2.5.1.

Thanks in advance.


From python at mrabarnett.plus.com  Mon Jul 27 13:55:57 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 27 Jul 2009 18:55:57 +0100
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <4A6DEA2D.6000408@mrabarnett.plus.com>

Reckoner wrote:
> Hi,
> X-Antispam: NO; Spamcatcher 5.2.1. Score 50
> 
> Observe the following:
> 
> In [202]: class Foo():
>    .....:     def __init__(self,h=[]):
>    .....:         self.h=h
>    .....:
>    .....:
> 
> In [203]: f=Foo()
> 
> In [204]: g=Foo()
> 
> In [205]: g.h
> Out[205]: []
> 
> In [206]: f.h
> Out[206]: []
> 
> In [207]: f.h.append(10)
> 
> In [208]: f.h
> Out[208]: [10]
> 
> In [209]: g.h
> Out[209]: [10]
> 
> The question is: why is g.h updated when I append to f.h?  Shouldn't
> g.h stay []?
> 
> What am I missing here?
> 
> I'm using Python 2.5.1.
> 
Default arguments are evaluated once and then shared, so don't use them
with mutable objects like lists. Do this instead:

     class Foo():
         def __init__(self, h=None):
             if h is None:
                 self.h = []
             else:
                 self.h = h


From __peter__ at web.de  Mon Jul 27 14:07:37 2009
From: __peter__ at web.de (Peter Otten)
Date: Mon, 27 Jul 2009 20:07:37 +0200
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<h4k8o8$ght$00$1@news.t-online.com>
	<bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
Message-ID: <h4kqd9$5h2$01$1@news.t-online.com>

r2 wrote:

> On Jul 27, 9:06 am, Peter Otten <__pete... at web.de> wrote:
>> r2 wrote:
>> > I have a memory dump from a machine I am trying to analyze. I can view
>> > the file in a hex editor to see text strings in the binary code. I
>> > don't see a way to save these ascii representations of the binary, so
>> > I went digging into Python to see if there were any modules to help.
>>
>> > I found one I think might do what I want it to do - the binascii
>> > module. Can anyone describe to me how to convert a raw binary file to
>> > an ascii file using this module. I've tried? Boy, I've tried.
>>
>> That won't work because a text editor doesn't need any help to convert
>> the bytes into characters. If it expects ascii it just will be puzzled by
>> bytes that are not valid ascii. Also, it will happily display byte
>> sequences that are valid ascii, but that you as a user will see as
>> gibberish because they were meant to be binary data by the program that
>> wrote them.
>>
>> > Am I correct in assuming I can get the converted binary to ascii text
>> > I see in a hex editor using this module? I'm new to this forensics
>> > thing and it's quite possible I am mixing technical terms. I am not
>> > new to Python, however. Thanks for your help.
>>
>> Unix has the "strings" commandline tool to extract text from a binary.
>> Get hold of a copy of the MinGW tools if you are on windows.
>>
>> Peter
> 
> Okay. Thanks for the guidance. I have a machine with Linux, so I
> should be able to do what you describe above. Could Python extract the
> strings from the binary as well? Just wondering.

As a special service for you here is a naive implementation to build upon:

#!/usr/bin/env python
import sys

wanted_chars = ["\0"]*256
for i in range(32, 127):
    wanted_chars[i] = chr(i)
wanted_chars[ord("\t")] = "\t"
wanted_chars = "".join(wanted_chars)

THRESHOLD = 4

for s in sys.stdin.read().translate(wanted_chars).split("\0"):
    if len(s) >= THRESHOLD:
        print s

Peter



From nagle at animats.com  Mon Jul 27 14:13:40 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 11:13:40 -0700
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
Message-ID: <4a6deda5$0$1639$742ec2ed@news.sonic.net>

John Nagle wrote:
> There's something strange about this URL:
> 
> "https://sagar310.pontins.com/sraep/"
> 
> It hangs Firefox 2; there's no short timeout, the web page just gets
> stuck in initial load for about ten minutes.  Then
> "The connection to sagar310.pontins.com was interrupted while the page 
> was loading."
> 
> It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.

     Correction: Linux is still hung at 5 hours, but Windows timed out
after about 15 minutes.

				John Nagle


From gagsl-py2 at yahoo.com.ar  Mon Jul 27 14:14:38 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 15:14:38 -0300
Subject: CRLF Newlines and libc
References: <6bcb4820-11be-4053-8e3b-849b00aba55a@c2g2000yqi.googlegroups.com>
Message-ID: <op.uxqnmoa2x6zn5v@gabriel.sleipnir-bsas>

En Mon, 27 Jul 2009 12:21:29 -0300, Eric <gmweezel at gmail.com> escribi?:

> I am working on the subprocess.Popen module for Google Summer of Code.
> Right now, I am having difficulty trying to work out how to deal with
> my '\n' newlines being converted to '\r\n' newlines when reading from
> a pipe on windows; see this blog post (http://subdev.blogspot.com/
> 2009/07/stdout.html) and this chain on Python-Dev (http://
> mail.python.org/pipermail/python-dev/2009-July/090720.html).
>
> Right now, unless there is way to disable the newline conversions, I
> am thinking I will just have to document the caveat and call it a day.
> Is there a better way to handle this?

It isn't clear to me what exactly your problem is. What are you reading,  
using which functions, how did you open the file? On the writing side, how  
did you open the file, which functions are used to write?

The Windows API functions like CreateFile, ReadFile, WriteFile... don't  
perform any kind of '\n' conversion, neither reading nor writing. On the  
other hand, the C library does differentiate between files opened in text  
mode or binary mode (this comes from the ANSI C standard, it's not Windows  
specific). The default is "text" mode (unless you add "b" to the fopen  
call, or O_BINARY to the open call). In that mode, '\n' is translated to  
'\r\n' on writing, and '\r\n' is translated to '\n' on reading.
Python files are implemented on top of the C library (on 2.x) so they  
inherit that behaviour.
Console programs written in C and using printf/fwrite/write to stdout  
share that behaviour too (standard handles are opened in text mode by  
default).

Note that """'\n' newlines being converted to '\r\n' newlines when  
reading""" cannot happen -- if you see '\r\n' when reading, it's because
a) you're reading the file in binary mode, and
b) the file was written in text mode.

b) is true for process output redirected to a pipe, so you'll have to fix  
a). How to do that, depends on what exactly you're doing.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 14:23:41 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 15:23:41 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
Message-ID: <op.uxqn1rxcx6zn5v@gabriel.sleipnir-bsas>

En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson  
<jakecjacobson at gmail.com> escribi?:

> I was wondering if this is due to the server having a invalid server
> cert?  If I go to this server in my browser, I get a "This server
> tried to identify itself with invalid information".  Is there a way to
> ignore this issue with Python?  Can I setup a trust store and add this
> server to the trust store?

I don't see the point in trusting someone that you know is telling lies  
about itself.

-- 
Gabriel Genellina



From kyrie at uh.cu  Mon Jul 27 14:25:47 2009
From: kyrie at uh.cu (Luis Alberto Zarrabeitia Gomez)
Date: Mon, 27 Jul 2009 14:25:47 -0400
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <1248719147.4a6df12b61835@mail.uh.cu>



Quoting Reckoner <reckoner at gmail.com>:

> Hi,
> 
> Observe the following:
> 
> In [202]: class Foo():
>    .....:     def __init__(self,h=[]):
>    .....:         self.h=h
[...]
> In [207]: f.h.append(10)
> 
> In [208]: f.h
> Out[208]: [10]
> 
> In [209]: g.h
> Out[209]: [10]
> 
> The question is: why is g.h updated when I append to f.h?  Shouldn't
> g.h stay []?

What you are seeing is basically the same that happens here: 

===
In [1]: def f(l=[]):
   ...:     l.append(1)
   ...:     print l
   ...: 

In [2]: f()
[1]

In [3]: f()
[1, 1]

In [4]: f()
[1, 1, 1]
===

The problem is that the default value "[]" is evaluated only once, at function
creation time, and not at invocation. Thus, every call to the function shares
the same default object. That is consistent with python's function type: the
"def" construct just creates a function object and initializes it with the code,
argument list and default values. That means that the default value are part of
the function object itself, regardless of when/if it is called:

===
In [5]: f.func_defaults
Out[5]: ([1, 1, 1],)
===

The recommended way of dealing with this case (mutable default arguments) is:

def f(l = None):
    if l is None:
        l = []
    # the code goes here.

(in your case, your g.__init__ and f.__init__ methods share the same
Foo.__init__ function, and thus, share the same default value [])

That is a very common python gotcha, and I think it is well documented in the
standard doc (but I can't find it right now, sorry). Unfortunately, it doesn't
become intuitive until you've spent a while understanding python's execution
model (and then you suddenly realize that it just makes sense).

[And now I wonder... how other languages do it? I've spent so much time with
python that reevaluating the default argument on invocation feels clumsy, but
I'm obviously tainted now...]

Regards,

-- 
Luis Zarrabeitia
Facultad de Matem?tica y Computaci?n, UH
http://profesores.matcom.uh.cu/~kyrie



-- 
Participe en Universidad 2010, del 8 al 12 de febrero de 2010
La Habana, Cuba 
http://www.universidad2010.cu



From niedziala at gazeta.pl  Mon Jul 27 14:43:36 2009
From: niedziala at gazeta.pl (Piotrek)
Date: Mon, 27 Jul 2009 20:43:36 +0200
Subject: where do I put resources (images,
	audio files) when I wrote Python program?
Message-ID: <h4ksgo$qa9$1@inews.gazeta.pl>

Hello,

I write a Python program. It will contain some images (in .png format), some
audio files (as .ogg) etc. Now I think where should my installer put these
files and how should I access them. What is the normal Python way of doing
that? I think about puting these files in /usr/share/myprogram and then
reading it the normal way (so the path "/usr/share/myprogram" would be just
hardwired in my program). Is it the way one usually does it in Python
program or is there any more sofisticated way?



From jakecjacobson at gmail.com  Mon Jul 27 14:52:08 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Mon, 27 Jul 2009 11:52:08 -0700 (PDT)
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
Message-ID: <157f16f9-2172-4fd5-8ec8-8d9569a3f186@f20g2000prn.googlegroups.com>

On Jul 27, 2:23?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson ?
> <jakecjacob... at gmail.com> escribi?:
>
> > I was wondering if this is due to the server having a invalid server
> > cert? ?If I go to this server in my browser, I get a "This server
> > tried to identify itself with invalid information". ?Is there a way to
> > ignore this issue with Python? ?Can I setup a trust store and add this
> > server to the trust store?
>
> I don't see the point in trusting someone that you know is telling lies ?
> about itself.
>
> --
> Gabriel Genellina

It is a test box that the team I am on runs.  That is why I would
trust it.


From mhearne808 at gmail.com  Mon Jul 27 14:57:28 2009
From: mhearne808 at gmail.com (mhearne808)
Date: Mon, 27 Jul 2009 11:57:28 -0700 (PDT)
Subject: where do I put resources (images, audio files) when I wrote 
	Python program?
References: <h4ksgo$qa9$1@inews.gazeta.pl>
Message-ID: <f5db92ff-f54f-47ea-bab8-f86883aa2eb3@d32g2000yqh.googlegroups.com>

On Jul 27, 12:43?pm, Piotrek <niedzi... at gazeta.pl> wrote:
> Hello,
>
> I write a Python program. It will contain some images (in .png format), some
> audio files (as .ogg) etc. Now I think where should my installer put these
> files and how should I access them. What is the normal Python way of doing
> that? I think about puting these files in /usr/share/myprogram and then
> reading it the normal way (so the path "/usr/share/myprogram" would be just
> hardwired in my program). Is it the way one usually does it in Python
> program or is there any more sofisticated way?

Usually the preferred method is either distutils (http://
docs.python.org/library/distutils.html#module-distutils) or setuptools
(http://peak.telecommunity.com/DevCenter/setuptools).  Either of these
will allow you to create source (".tar.gz") or binary distributions
that can be installed relatively easily on a target machine.

Good luck,
Mike


From wilk at flibuste.net  Mon Jul 27 15:04:59 2009
From: wilk at flibuste.net (William Dode)
Date: 27 Jul 2009 19:04:59 GMT
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <4a6dfa5b$0$10245$426a74cc@news.free.fr>

On 27-07-2009, MRAB wrote:
> Hi all,
>
> I've been working on a new implementation of the re module. The details
> are at http://bugs.python.org/issue2636, specifically from
> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
> Python 2.6 on Windows if you want to try it out.
>

Someone can remember me how to compile it (on debian lenny), if possible 
with python2.5. I've also python3.1 that i build alone...

I could test it with pytextile, i've a bunch of texts to bench and 
compare.

Did you announce it on the unladen-swallow list ? They wanted to hack on 
RE also...


-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From joshua at joshuakugler.com  Mon Jul 27 15:09:47 2009
From: joshua at joshuakugler.com (Joshua Kugler)
Date: Mon, 27 Jul 2009 11:09:47 -0800
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<24654358.post@talk.nabble.com>
Message-ID: <h4ku1s$u8h$1@ger.gmane.org>

Dr. Phillip M. Feldman wrote:

> 
> "As far as I know, there is no programming language which treats scalars
> like ints as if they were
> vectors of length 1"
> 
> Actually, Matlab does:
> 
>>> length(5)
> ans =
>      1
>>> 

Oddly enough, so does Perl:

$ print length(44)
2

(that's in the Zoidberg shell)

j




From deets at nospam.web.de  Mon Jul 27 15:26:46 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Mon, 27 Jul 2009 21:26:46 +0200
Subject: Wrapping prstat on Solaris
In-Reply-To: <mailman.3776.1248704814.8015.python-list@python.org>
References: <mailman.3776.1248704814.8015.python-list@python.org>
Message-ID: <7d6dbmF2ahp61U1@mid.uni-berlin.de>

skip at pobox.com schrieb:
> At work we currently use top to monitor ongoing system utilization on our
> Solaris systems.  As time has moved on though, use of top has become
> problematic.  Our admins want us to switch to prstat, Sun's top-like
> command.  It works fine however doesn't emit a timestamp at each display
> interval, so it's essentially impossible looking at a prstat output
> file to determine when the particular "screen" was emitted.
> 
> If figured, "No problem.  I'll just write a little wrapper."  Alas, that is
> proving harder than I thought.  I can run prstat directing output to a file
> and it seems to blast out a block of lines every N seconds, but when run
> from inside a Python script I can't seem to make the damn thing not
> massively buffer its output.  Accordingly, my script doesn't really see the
> output as its emitted, so the timestamp line it prepends to a block of
> output is off.
> 
> I'm currently using subprocess.Popen like so:
> 
>     os.environ["TERM"] = "dumb"
>     cmd = "prstat -c %s" % " ".join(sys.argv[1:])
>     pipe = Popen(cmd, shell=True, bufsize=1, stdout=PIPE).stdout
> 
> I've tried these other variants as well:
> 
>   * prefacing the prstat command with unbuffer (the tcl/expect thingamabob)
> 
>   * explicitly redirect the prstat output to /dev/stdout
> 
>   * setting bufsize to 0
> 
>   * used os.popen instead of Subprocess.Popen
> 
> Nothing seems to help.  I always seem to see about 30 seconds of data at
> once (I'm currently using a 5-second interval and 10 lines of output).  I
> would have expected that prstat would simply flush stdout after each block
> of output.
> 
> Any ideas about how to get prstat to cooperate better?

Use pexpect, which will make the program believe it runs in a terminal, 
and not buffer the output.

Diez


From invalid at invalid  Mon Jul 27 15:27:47 2009
From: invalid at invalid (Grant Edwards)
Date: Mon, 27 Jul 2009 14:27:47 -0500
Subject: len() should always return something
References: <24639361.post@talk.nabble.com>
	<0279f6df$0$5185$c3e8da3@news.astraweb.com>
	<24654358.post@talk.nabble.com>
	<mailman.3791.1248721801.8015.python-list@python.org>
Message-ID: <qtOdna1pcdIuYvDXnZ2dnUVZ_t6dnZ2d@posted.visi>

On 2009-07-27, Joshua Kugler <joshua at joshuakugler.com> wrote:
> Dr. Phillip M. Feldman wrote:
>
>> "As far as I know, there is no programming language which
>> treats scalars like ints as if they were vectors of length 1"
>> 
>> Actually, Matlab does:
>> 
>>>> length(5)
>> ans =
>>      1
>>>> 
>
> Oddly enough, so does Perl:
>
> $ print length(44)
> 2

No, that's not really treating scalars as vectors of length 1.
Were it doing so, length(44) would be 1 rather than 2.  What
Perl does is treat everything as a string.

-- 
Grant Edwards                   grante             Yow! I was making donuts
                                  at               and now I'm on a bus!
                               visi.com            


From wolfgang at rohdewald.de  Mon Jul 27 15:27:55 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Mon, 27 Jul 2009 21:27:55 +0200
Subject: New implementation of re module
In-Reply-To: <4A6DD6FB.8040609@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
Message-ID: <200907272127.55328.wolfgang@rohdewald.de>

On Monday 27 July 2009, MRAB wrote:
> I've been working on a new implementation of the re module. The
> details are at http://bugs.python.org/issue2636, specifically from
> http://bugs.python.org/issue2636#msg90954. I've included a .pyd
> file for Python 2.6 on Windows if you want to try it out.

how do I compile _regex.c on Linux?

-- 
Wolfgang


From benjamin.kaplan at case.edu  Mon Jul 27 15:30:31 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Mon, 27 Jul 2009 15:30:31 -0400
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <ec96e1390907271230o491ae706v1ddc6717b9dcb363@mail.gmail.com>

On Mon, Jul 27, 2009 at 1:40 PM, Reckoner<reckoner at gmail.com> wrote:
> Hi,
>
> Observe the following:
>
> In [202]: class Foo():
> ? .....: ? ? def __init__(self,h=[]):
> ? .....: ? ? ? ? self.h=h
> ? .....:
> ? .....:
>
> In [203]: f=Foo()
>
> In [204]: g=Foo()
>
> In [205]: g.h
> Out[205]: []
>
> In [206]: f.h
> Out[206]: []
>
> In [207]: f.h.append(10)
>
> In [208]: f.h
> Out[208]: [10]
>
> In [209]: g.h
> Out[209]: [10]
>
> The question is: why is g.h updated when I append to f.h? ?Shouldn't
> g.h stay []?
>
> What am I missing here?
>
> I'm using Python 2.5.1.
>
> Thanks in advance.


. It has to do with the way Python handles functions and class
methods. Basically, when the parser creates the class Foo, it also
creates all of Foo's class variables and functions. It's at this
point, and only at this point, that the default parameter is
evaluated.

When you make an instance of Foo, just wraps the function __init__ by
filling in the initial parameter. Because both f and g are really
using the Foo.__init__ function (as opposed to separate f.__init__ and
g.__init__ methods), they share the same default parameter, a list
that was created at the very beginning.

Since f.h and g.h both refer to the same list, updating f.h will also
update g.h (and the default parameter). That's why it's a bad idea to
use mutable default parameters- use either None

class Foo(object) :
   def __init__(self, h=None) :
      if h is None:
         h = []

or, if None is an acceptable value, make a sentinel value

sentinel = object()
class Foo(object) :
   def __init__(self, h = sentinel) :
      if h is sentinel:
         h = []
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From rlichlighter at gmail.com  Mon Jul 27 15:33:21 2009
From: rlichlighter at gmail.com (r2)
Date: Mon, 27 Jul 2009 12:33:21 -0700 (PDT)
Subject: Convert raw binary file to ascii
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<h4k8o8$ght$00$1@news.t-online.com>
	<bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
	<h4kqd9$5h2$01$1@news.t-online.com>
Message-ID: <f1006be7-bad7-41ec-a187-792194fbcd51@y19g2000yqy.googlegroups.com>

On Jul 27, 2:07?pm, Peter Otten <__pete... at web.de> wrote:
> r2 wrote:
> > On Jul 27, 9:06 am, Peter Otten <__pete... at web.de> wrote:
> >> r2 wrote:
> >> > I have a memory dump from a machine I am trying to analyze. I can view
> >> > the file in a hex editor to see text strings in the binary code. I
> >> > don't see a way to save these ascii representations of the binary, so
> >> > I went digging into Python to see if there were any modules to help.
>
> >> > I found one I think might do what I want it to do - the binascii
> >> > module. Can anyone describe to me how to convert a raw binary file to
> >> > an ascii file using this module. I've tried? Boy, I've tried.
>
> >> That won't work because a text editor doesn't need any help to convert
> >> the bytes into characters. If it expects ascii it just will be puzzled by
> >> bytes that are not valid ascii. Also, it will happily display byte
> >> sequences that are valid ascii, but that you as a user will see as
> >> gibberish because they were meant to be binary data by the program that
> >> wrote them.
>
> >> > Am I correct in assuming I can get the converted binary to ascii text
> >> > I see in a hex editor using this module? I'm new to this forensics
> >> > thing and it's quite possible I am mixing technical terms. I am not
> >> > new to Python, however. Thanks for your help.
>
> >> Unix has the "strings" commandline tool to extract text from a binary.
> >> Get hold of a copy of the MinGW tools if you are on windows.
>
> >> Peter
>
> > Okay. Thanks for the guidance. I have a machine with Linux, so I
> > should be able to do what you describe above. Could Python extract the
> > strings from the binary as well? Just wondering.
>
> As a special service for you here is a naive implementation to build upon:
>
> #!/usr/bin/env python
> import sys
>
> wanted_chars = ["\0"]*256
> for i in range(32, 127):
> ? ? wanted_chars[i] = chr(i)
> wanted_chars[ord("\t")] = "\t"
> wanted_chars = "".join(wanted_chars)
>
> THRESHOLD = 4
>
> for s in sys.stdin.read().translate(wanted_chars).split("\0"):
> ? ? if len(s) >= THRESHOLD:
> ? ? ? ? print s
>
> Peter- Hide quoted text -
>
> - Show quoted text -

Perfect! Thanks.


From mondi at cs.unibo.it  Mon Jul 27 15:35:51 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Mon, 27 Jul 2009 19:35:51 +0000
Subject: ioctl on socket
Message-ID: <h4knsn$u76$1@lec.cs.unibo.it>

Is there a reason why there is no ioctl interface for socket either then
for windows platform? It's technical issues or what else??

thank in advance
	jacopo


From python at mrabarnett.plus.com  Mon Jul 27 16:00:48 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Mon, 27 Jul 2009 21:00:48 +0100
Subject: New implementation of re module
In-Reply-To: <4a6dfa5b$0$10245$426a74cc@news.free.fr>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<4a6dfa5b$0$10245$426a74cc@news.free.fr>
Message-ID: <4A6E0770.4000908@mrabarnett.plus.com>

William Dode wrote:
> On 27-07-2009, MRAB wrote:
>> Hi all,
>>
>> I've been working on a new implementation of the re module. The details
>> are at http://bugs.python.org/issue2636, specifically from
>> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>> Python 2.6 on Windows if you want to try it out.
>>
> 
> Someone can remember me how to compile it (on debian lenny), if possible 
> with python2.5. I've also python3.1 that i build alone...
> 
> I could test it with pytextile, i've a bunch of texts to bench and 
> compare.
> 
All I can do is point you to 
http://docs.python.org/extending/extending.html.

For Linux (which I don't have) you'll need to use _regex.h and _regex.c
to compile to _regex.so instead of _regex.pyd.

> Did you announce it on the unladen-swallow list ? They wanted to hack on 
> RE also...
> 
No. I haven't subscribed to it.


From davea at ieee.org  Mon Jul 27 16:07:16 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 16:07:16 -0400
Subject: Convert raw binary file to ascii
In-Reply-To: <bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>	<h4k8o8$ght$00$1@news.t-online.com>
	<bbe60a76-fd9a-4762-bd4d-07aa725e9c70@e11g2000yqo.googlegroups.com>
Message-ID: <4A6E08F4.8080203@ieee.org>

r2 wrote:
> On Jul 27, 9:06 am, Peter Otten <__pete... at web.de> wrote:
>   
>> r2 wrote:
>>     
>>> I have a memory dump from a machine I am trying to analyze. I can view
>>> the file in a hex editor to see text strings in the binary code. I
>>> don't see a way to save these ascii representations of the binary, so
>>> I went digging into Python to see if there were any modules to help.
>>>       
>>> I found one I think might do what I want it to do - the binascii
>>> module. Can anyone describe to me how to convert a raw binary file to
>>> an ascii file using this module. I've tried? Boy, I've tried.
>>>       
>> That won't work because a text editor doesn't need any help to convert the
>> bytes into characters. If it expects ascii it just will be puzzled by bytes
>> that are not valid ascii. Also, it will happily display byte sequences that
>> are valid ascii, but that you as a user will see as gibberish because they
>> were meant to be binary data by the program that wrote them.
>>
>>     
>>> Am I correct in assuming I can get the converted binary to ascii text
>>> I see in a hex editor using this module? I'm new to this forensics
>>> thing and it's quite possible I am mixing technical terms. I am not
>>> new to Python, however. Thanks for your help.
>>>       
>> Unix has the "strings" commandline tool to extract text from a binary.
>> Get hold of a copy of the MinGW tools if you are on windows.
>>
>> Peter
>>     
>
> Okay. Thanks for the guidance. I have a machine with Linux, so I
> should be able to do what you describe above. Could Python extract the
> strings from the binary as well? Just wondering.
>
>   
Yes, you could do the same thing in Python easily enough.  And with the 
advantage that you could define your own meanings for "characters."

The memory dump could be storing characters that are strictly ASCII.  Or 
it could have EBCDIC, or UTF-8.  And it could be Unicode, 16 bit or 32 
bits, and big-endian or little-endian.  Or the characters could be in 
some other format specific to a particular program.

However, it's probably very useful to see what a "strings" program might 
look like, because you can quickly code variations on it, to suit your 
particular data.
Something like the following (totally untested)

def isprintable(char):
    return 0x20 <= char <= 0x7f

def string(filename):
    data = open(filename, "rb").read()
    count = 0
    line = ""
    for ch in data:
        if isprintable(ch):
             count += 1
             line = line + ch
        else:
             if count > 4 :     #cutoff, don't print strings smaller 
than this because they're probably just coincidence
                 print line
                 count = 0
                 line= ""
    print line


Now you can change the definition of what's "printable", you can change 
the min-length that you care about.  And of course you can fine-tune 
things like max-length lines and such.

DaveA



From davea at dejaviewphoto.com  Mon Jul 27 16:14:14 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Mon, 27 Jul 2009 16:14:14 -0400
Subject: Help understanding the decisions *behind* python? - immutable
	objects
In-Reply-To: <ec96e1390907270541p7846d649r7d8fd6e429c64a56@mail.gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com>	<mailman.3511.1248244497.8015.python-list@python.org>	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
	<ec96e1390907270541p7846d649r7d8fd6e429c64a56@mail.gmail.com>
Message-ID: <4A6E0A96.60001@dejaviewphoto.com>

Benjamin Kaplan wrote:
> On Sun, Jul 26, 2009 at 2:24 PM, John Nagle<nagle at animats.com> wrote:
>   
>> Beni Cherniavsky wrote:
>>     
>>> On Jul 22, 9:36 am, Hendrik van Rooyen <hend... at microcorp.co.za>
>>> wrote:
>>>       
>>>> On Tuesday 21 July 2009 15:49:59 Inky 788 wrote:
>>>> <snip>
>>> problem.
>>>       
>>    An interesting issue is Python objects, which are always mutable.
>> A "dict" of Python objects is allowed, but doesn't consider
>> the contents of the objects, just their identity (address). Only
>> built-in types are immutable; one cannot create a class of immutable
>> objects.
>> So things like "frozenset" had to be built into the language.
>> A tuple is really a frozen list.  Arguably, frozen objects
>> should have been a general concept.  Conceptually, they're
>> simple - once "__init__" has run, there can be no more changes
>> to fields of the object.
>>
>>    Compare the C++ approach, where you can have a "map" of
>> any object that defines the "<" operator.  Python has
>> "__cmp__" for objects, but built-in dictionaries don't use it.
>> Of course, one could create a "map" class in Python that
>> uses "__cmp__", which would allow dictionary-type operations
>> on arbitrary objects.
>>     
>
>
> Python dictionaries are hash maps so they use hashes, not comparisons,
> to store objects. By default the hash is equal to the object's
> identity but all you need to do to change it is define your own
> __hash__ method. If you were to make a C++ hash map, it wouldn't use
> comparisons either.
>
> <snip>
>   
>
I think you'll find that to make a proper dict of user-objects, you need 
to define not only __hash__(), but also __eq__() methods.   A hash is 
only a starting place.  In case of collision, the dict class calls 
another method to make sure.

And of course, for the dict to function reasonably, you have to make 
sure that the hash and eq functions return consistent results, at least 
pretending that the objects involved are immutable.

DaveA



From ccurvey at gmail.com  Mon Jul 27 16:16:28 2009
From: ccurvey at gmail.com (Chris Curvey)
Date: Mon, 27 Jul 2009 13:16:28 -0700 (PDT)
Subject: PyPDF and print restrictions
Message-ID: <90034475-cf07-4a57-b8cf-ec2949e0e544@d23g2000vbm.googlegroups.com>

Has anyone out there been able to enforce print restrictions on a PDF
document by using PyPDF? The documentation for "encrypt" states:

 # @param user_pwd The "user password", which allows for opening and
reading
 # the PDF file with the restrictions provided.

But there is no parameter for providing a restriction, and I can't
find a reference to any kind of restriction besides this comment in
the docs.

Thanks in advance!



From nagle at animats.com  Mon Jul 27 16:24:34 2009
From: nagle at animats.com (John Nagle)
Date: Mon, 27 Jul 2009 13:24:34 -0700
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6deda5$0$1639$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
Message-ID: <4a6e0c53$0$1644$742ec2ed@news.sonic.net>

John Nagle wrote:
> John Nagle wrote:
>> There's something strange about this URL:
>>
>> "https://sagar310.pontins.com/sraep/"
>>
>> It hangs Firefox 2; there's no short timeout, the web page just gets
>> stuck in initial load for about ten minutes.  Then
>> "The connection to sagar310.pontins.com was interrupted while the page 
>> was loading."
>>
>> It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.
> 
>     Correction: Linux is still hung at 5 hours, but Windows timed out
> after about 15 minutes.
> 
Further update: M2Crypto on Windows now hung on that URL for hours.  Last time,
the connection apparently failed and the program got unstuck.

It's waiting for something to happen inside SSL connection setup.

				John Nagle


From djames.suhanko at gmail.com  Mon Jul 27 16:25:32 2009
From: djames.suhanko at gmail.com (Djames Suhanko)
Date: Mon, 27 Jul 2009 17:25:32 -0300
Subject: Discovery IP in connection
Message-ID: <fd9e6bba0907271325i5b32060ah6930fe5db336f6ee@mail.gmail.com>

Hello,all!
 I wrote a little programa that listening UDP packets. A can receive
the messages, but I can't see the the origin IP.
 How can I to  get the remote IP address in connection?

My source:

#!/usr/bin/env python
import socket
mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
mySocket.bind ( ( '', 514 ) )

data, addr = mySocket.recvfrom(100)
print data

-- 
Djames Suhanko
LinuxUser 158.760


From 71david at libero.it  Mon Jul 27 16:35:01 2009
From: 71david at libero.it (David)
Date: Mon, 27 Jul 2009 22:35:01 +0200
Subject: Gracefully exiting CLI application
Message-ID: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>

Greetings,

I am writing a command line application, and I need to perform some cleaning
on exit even if the process is killed.
How can I do that with python?

Thank you.
David.


From erikwickstrom at gmail.com  Mon Jul 27 16:38:25 2009
From: erikwickstrom at gmail.com (erikcw)
Date: Mon, 27 Jul 2009 13:38:25 -0700 (PDT)
Subject: Download the "head" of a large file?
Message-ID: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>

I'm trying to figure out how to download just the first few lines of a
large (50mb) text file form a server to save bandwidth.  Can Python do
this?

Something like the Python equivalent of curl http://url.com/file.xml |
head -c 2048

Thanks!
Erik


From tjreedy at udel.edu  Mon Jul 27 16:47:34 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Mon, 27 Jul 2009 16:47:34 -0400
Subject: Distinguishing active generators from exhausted ones
In-Reply-To: <027d38a5$0$5185$c3e8da3@news.astraweb.com>
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>	<877hxw4avj.fsf@benfinney.id.au>	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>	<mailman.3752.1248653417.8015.python-list@python.org>	<027d0d84$0$5185$c3e8da3@news.astraweb.com>	<mailman.3757.1248674553.8015.python-list@python.org>
	<027d38a5$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <h4l3p6$jgj$1@ger.gmane.org>

Steven D'Aprano wrote:
> On Mon, 27 Jul 2009 02:02:19 -0400, Terry Reedy wrote:
> 
>> Steven D'Aprano wrote:
>>> On Sun, 26 Jul 2009 20:10:00 -0400, Terry Reedy wrote:
>>>
>>>> Michal Kwiatkowski wrote:
>>>>
>>>>> The thing is I don't need the next item. I need to know if the
>>>>> generator has stopped without invoking it.
>>>> Write a one-ahead iterator class, which I have posted before, that
>>>> sets .exhausted to True when next fails.
>>>
>>> And hope that the generator doesn't have side-effects...
>> If run to exhastion, the same number of side-effects happen. The only
>> difference is that they each happen once step happpen sooner. For
>> reading a file that is irrelevant. Much else, and the iterator is not
>> just an iterator.
> 
> I believe the OP specifically said he needs to detect whether or not an 
> iterator is exhausted, without running it to exhaustion, so you shouldn't 
> assume that the generator has been exhausted.

I believe the OP said he needs to determine whether or not an iterator 
(specifically generator) is exhausted without consuming an item when it 
is not. That is slightly different. The wrapper I suggested makes that 
easy. I am obviously not assuming exhaustion when there is a .exhausted 
True/False flag to check.

There are two possible definition of 'exhausted': 1) will raise 
StopIteration on the next next() call; 2) has raised StopIteration at 
least once. The wrapper converts 2) to 1), which is to say, it obeys 
definition 1 once the underlying iteration has obeyed definition 2.

Since it is trivial to set 'exhausted=True' in the generator user code 
once StopIteration has been raised (meaning 2), I presume the OP wants 
the predictive meaning 1).

Without a iterator class wrapper, I see no way to predict what a 
generator will do (expecially, raise StopIteration the first time) 
without analyzing its code and local variable state.

I said in response to YOU that once exhaustion has occurred, then the 
same number of side effects would have occurred.

> When it comes to side-effects, timing matters.

Sometimes. And I admitted that possibility (slight garbled).

  For example, a generator
> which cleans up after it has run (deleting temporary files, closing 
> sockets, etc.) will leave the environment in a different state if run to 
> exhaustion than just before exhaustion. Even if you store the final 
> result in a one-ahead class, you haven't saved the environment, and that 
> may be significant.

Of course, an eager-beaver generator written to be a good citizen might 
well close resources as soon as it knows *they* are exhausted, long 
before *it* yields the last items from the in-memory last block read. 
For all I know, file.readlines could do such.

Assuming that is not the case, the cleanup will not happen until the 
what turns out to be the final item is requested from the wrapper. Once 
cleanup has happened, .exhausted will be set to True. If proper 
processing of even the last item requires that cleanup not have 
happened, then that and prediction of exhaustion are incompatible. One 
who wants both should write an iterator class instead of generator function.

> (Of course, it's possible that it isn't significant. Not all differences 
> make a difference.)
> 
> The best advice is, try to avoid side-effects, especially in generators.

Agreed.

Terry Jan Reedy





From davea at ieee.org  Mon Jul 27 16:53:12 2009
From: davea at ieee.org (Dave Angel)
Date: Mon, 27 Jul 2009 16:53:12 -0400
Subject: where do I put resources (images, audio files) when I wrote Python
	program?
In-Reply-To: <h4ksgo$qa9$1@inews.gazeta.pl>
References: <h4ksgo$qa9$1@inews.gazeta.pl>
Message-ID: <4A6E13B8.4080806@ieee.org>

Piotrek wrote:
> Hello,
>
> I write a Python program. It will contain some images (in .png format), some
> audio files (as .ogg) etc. Now I think where should my installer put these
> files and how should I access them. What is the normal Python way of doing
> that? I think about puting these files in /usr/share/myprogram and then
> reading it the normal way (so the path "/usr/share/myprogram" would be just
> hardwired in my program). Is it the way one usually does it in Python
> program or is there any more sofisticated way?
>
>
>   
I think this question is mostly independent of the issue of what's used 
to actually install the files.

My answer is to put read-only files right with the py* files, and 
writable files in the user's space.  In the former case, you can find 
the files by parsing __file__ for one of your modules.  In the latter 
case, it's system dependent.  But I'd start with a single file which is 
put in a conventional place (for your target OS).  That will be a 
configuration file ("preferences files"), which specifies, among other 
things, where everything else will be written.  Somebody else will have 
to tell you what the Unix convention would be.

In the case of Windows, the first "file" would just be a registry 
entry.  And I wouldn't write any of the actual files till the user had 
configured things, either during installation or during the first run 
(with a File->Preferences menu setup).




From zapwireDASHgroups at yahoo.com  Mon Jul 27 17:04:20 2009
From: zapwireDASHgroups at yahoo.com (Joel Koltner)
Date: Mon, 27 Jul 2009 14:04:20 -0700
Subject: len() should always return something
References: <24639361.post@talk.nabble.com> <7ct4b8F29mednU1@mid.uni-berlin.de>
	<mailman.3699.1248490256.8015.python-list@python.org>
Message-ID: <pDobm.484275$6p1.246121@en-nntp-02.dc1.easynews.com>

"Dr. Phillip M. Feldman" <pfeldman at verizon.net> wrote in message 
news:mailman.3699.1248490256.8015.python-list at python.org...
> Here's a simple-minded example:
...
> This function works fine if xs is a list of floats, but not if it is single
> float.  It can be made to work as follows:

Wow, you could substitute "Matlab" for "Python" in your post and it'd still be 
just as good. :-)




From zuo at chopin.edu.pl  Mon Jul 27 17:09:14 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Mon, 27 Jul 2009 23:09:14 +0200
Subject: Convert raw binary file to ascii
In-Reply-To: <PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>
References: <af2b8d61-cff6-4d1f-801a-0bb160e5f24f@c14g2000yqm.googlegroups.com>
	<PPmdnaNvV-cUKPDXnZ2dnUVZ_j5i4p2d@posted.visi>
Message-ID: <op.uxqvpolpfvx12t@jerzozwiesz.home.aster.pl>

Hello Friends,

It's my first post to python-list, so first let me introduce myself...
* my name is Jan Kaliszewski,
* country -- Poland,
* occupation -- composer (studied in F. Chopin Academy of Music @Warsaw)
                 and programmer (currently in Record System company,
                                 working on Anakonda -- ERP system for
                                 big companies [developed in Python + WX
                                 + Postgres]).

Now, to the matter...

27-07-2009 Grant Edwards <invalid at invalid.chopin.edu.pl> wrote:

> On 2009-07-27, r2 <rlichlighter at gmail.com> wrote:
>
>> I have a memory dump from a machine I am trying to analyze. I can view
>> the file in a hex editor to see text strings in the binary code. I
>> don't see a way to save these ascii representations of the binary,
>
> $ strings memdump.binary >memdump.strings
>
> $ hexdump -C memdump.binary >memdump.hex+as

Do You (r2) want to do get ASCII substrings (i.e. extract only those
pieces of file that consist of ASCII codes -- i.e. 7-bit values -- i.e in
range 0...127), or rather "possibly readable ascii representation" of
the whole file, with printable ascii characters preserved 'as is' and
not-printable/non-ascii characters being replaced with their codes
(e.g. with '\x...' notation).

If the latter, you probably want something like this:

import codecs
with open('memdump.binary', 'rb') as source:
     with open('memdump.txt', 'w') as target:
         for quasiline in codecs.iterencode(source, 'string_escape'):
             target.write(quasiline)

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From martin.hellwig at dcuktec.org  Mon Jul 27 17:12:23 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Mon, 27 Jul 2009 22:12:23 +0100
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6e0c53$0$1644$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
	<4a6e0c53$0$1644$742ec2ed@news.sonic.net>
Message-ID: <fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>

John Nagle wrote:
> John Nagle wrote:
>> John Nagle wrote:
>>> There's something strange about this URL:
>>>
>>> "https://sagar310.pontins.com/sraep/"
>>>
>>> It hangs Firefox 2; there's no short timeout, the web page just gets
>>> stuck in initial load for about ten minutes.  Then
>>> "The connection to sagar310.pontins.com was interrupted while the 
>>> page was loading."
>>>
>>> It hangs M2Crypto 0.17 on both Linux and Windows, for at least 4 hours.
>>
>>     Correction: Linux is still hung at 5 hours, but Windows timed out
>> after about 15 minutes.
>>
> Further update: M2Crypto on Windows now hung on that URL for hours.  
> Last time,
> the connection apparently failed and the program got unstuck.
> 
> It's waiting for something to happen inside SSL connection setup.
> 
>                 John Nagle

It looks to me like the SSL handshake is not done properly from the 
server side.

Compare the output of:
openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts -msg

With (for example):
openssl s_client -host www.google.com -port 443 -debug -showcerts -msg

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From shai at platonix.com  Mon Jul 27 17:15:00 2009
From: shai at platonix.com (Shai)
Date: Mon, 27 Jul 2009 14:15:00 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au>
	<mailman.3774.1248703529.8015.python-list@python.org>
Message-ID: <c93175a3-e8fa-4e18-a10c-1516b72dcdb9@33g2000vbe.googlegroups.com>

On Jul 27, 5:05?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> Ben Finney wrote:
> >
> > The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
> > applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
> > the method, the original docstring is not associated with it.
>
> I've also tried within the python interpreter, and it can perfectly
> solve docstring inheritance. So why would you explicitly assign
> docstring to child methods ?
>

What do you mean by "can perfectly solve docstring inheritance" ?

After the following,

class Foo(object):
    def foo(self):
        "Frobber"
        pass

class Bar(Foo):
    def foo(self):
        pass

help(Bar.foo) does not display "Frobber" on my interpreter.



From zuo at chopin.edu.pl  Mon Jul 27 17:35:23 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Mon, 27 Jul 2009 23:35:23 +0200
Subject: Gracefully exiting CLI application
In-Reply-To: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
Message-ID: <op.uxqww9e7fvx12t@jerzozwiesz.home.aster.pl>

27-07-2009 o 22:35:01 David <71david at libero.it> wrote:

> I am writing a command line application, and I need to perform some  
> cleaning
> on exit even if the process is killed.
> How can I do that with python?

See: http://docs.python.org/library/signal.html

Cheers,
*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From constant.beta at gmail.com  Mon Jul 27 17:37:57 2009
From: constant.beta at gmail.com (Michal Kwiatkowski)
Date: Mon, 27 Jul 2009 14:37:57 -0700 (PDT)
Subject: Distinguishing active generators from exhausted ones
References: <736219d7-cf95-456a-a5d9-2e12acfd6635@k1g2000yqf.googlegroups.com>
	<877hxw4avj.fsf@benfinney.id.au>
	<2986f530-2195-405a-8d40-1ba15b7de6cf@d4g2000yqa.googlegroups.com>
	<mailman.3752.1248653417.8015.python-list@python.org>
	<027d0d84$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3757.1248674553.8015.python-list@python.org>
	<027d38a5$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3798.1248727674.8015.python-list@python.org>
Message-ID: <47bfd80f-2f61-462e-8789-811a2c836b5e@n2g2000vba.googlegroups.com>

On Jul 27, 10:47?pm, Terry Reedy <tjre... at udel.edu> wrote:
> There are two possible definition of 'exhausted': 1) will raise
> StopIteration on the next next() call; 2) has raised StopIteration at
> least once. The wrapper converts 2) to 1), which is to say, it obeys
> definition 1 once the underlying iteration has obeyed definition 2.
>
> Since it is trivial to set 'exhausted=True' in the generator user code
> once StopIteration has been raised (meaning 2), I presume the OP wants
> the predictive meaning 1).

No, I meant the second meaning (i.e. generator is exhausted when it
has returned instead of yielding).

While, as you showed, it is trivial to create a generator that will
have the "exhausted" flag, in my specific case I have no control over
the user code. I have to use what the Python genobject API gives me
plus the context of the trace function.

Cheers,
mk


From ben+python at benfinney.id.au  Mon Jul 27 17:40:32 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Tue, 28 Jul 2009 07:40:32 +1000
Subject: Gracefully exiting CLI application
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
Message-ID: <873a8h4xf3.fsf@benfinney.id.au>

David <71david at libero.it> writes:

> I am writing a command line application, and I need to perform some
> cleaning on exit even if the process is killed. How can I do that with
> python?

Write an ?exit handler? function, then use ?atexit.register?
<URL:http://docs.python.org/library/atexit> to register yours for
processing whenever the program exits.

-- 
 \        ?Pinky, are you pondering what I'm pondering?? ?Wuh, I think |
  `\    so, Brain, but will they let the Cranberry Duchess stay in the |
_o__)                         Lincoln Bedroom?? ?_Pinky and The Brain_ |
Ben Finney


From zuo at chopin.edu.pl  Mon Jul 27 17:52:27 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Mon, 27 Jul 2009 23:52:27 +0200
Subject: Gracefully exiting CLI application
In-Reply-To: <873a8h4xf3.fsf@benfinney.id.au>
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
	<873a8h4xf3.fsf@benfinney.id.au>
Message-ID: <op.uxqxppj9fvx12t@jerzozwiesz.home.aster.pl>

27-07-2009 Ben Finney <ben+python at benfinney.id.au> wrote:

> David <71david at libero.it> writes:
>
>> I am writing a command line application, and I need to perform some
>> cleaning on exit even if the process is killed. How can I do that with
>> python?
>
> Write an ?exit handler? function, then use ?atexit.register?
> <URL:http://docs.python.org/library/atexit> to register yours for
> processing whenever the program exits.

Unfortunately neither sys.exitfunc nor function registered with
atexit.register() are called when process is killed with signal.

As I wrote, you must use signals. Though sometimes it's a good idea
to combine these two techniques (i.e. signal handlers call sys.exit(),
then sys.exitfunc/or function registered with atexit does the actual
cleaning actions).

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From bcharrow at csail.mit.edu  Mon Jul 27 18:33:51 2009
From: bcharrow at csail.mit.edu (Ben Charrow)
Date: Mon, 27 Jul 2009 18:33:51 -0400
Subject: Download the "head" of a large file?
In-Reply-To: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
Message-ID: <4A6E2B4F.70102@csail.mit.edu>

erikcw wrote:
> ...download just the first few lines of a large (50mb) text file form a
> server to save bandwidth..... Something like the Python equivalent of curl
> http://url.com/file.xml | head -c 2048

If you're OK calling curl and head from within python:

from subprocess import Popen, PIPE
url = "http://docs.python.org/"
p1 = Popen(["curl", url], stdout = PIPE, stderr = PIPE)
p2 = Popen(["head", "-c", "1024"], stdin = p1.stdout, stdout = PIPE)
p2.communicate()[0]

If you want a pure python approach:

import urllib2
url = "http://docs.python.org/"
req = urllib2.Request(url)
f = urllib2.urlopen(req)
f.read(1024)

HTH,
Ben


From gallium.arsenide at gmail.com  Mon Jul 27 18:40:25 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Mon, 27 Jul 2009 15:40:25 -0700 (PDT)
Subject: Download the "head" of a large file?
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
Message-ID: <5579245f-b8cb-44cc-9b5f-1e7009422a58@g19g2000vbi.googlegroups.com>

On Jul 27, 4:38?pm, erikcw <erikwickst... at gmail.com> wrote:
> I'm trying to figure out how to download just the first few lines of a
> large (50mb) text file form a server to save bandwidth. ?Can Python do
> this?
>
> Something like the Python equivalent of curlhttp://url.com/file.xml|
> head -c 2048

urllib.urlopen gives you a file-like object, which you can then read
line by line or in fixed-size chunks.  For example:

import urllib
chunk = urllib.urlopen('http://url.com/file.xml').read(2048)

At that point, chunk is just bytes, which you can write to a local
file, print, or whatever it is you want.

John


From steve at REMOVE-THIS-cybersource.com.au  Mon Jul 27 19:00:27 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 27 Jul 2009 23:00:27 GMT
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
Message-ID: <027e226c$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 15:23:41 -0300, Gabriel Genellina wrote:

> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson
> <jakecjacobson at gmail.com> escribi?:
> 
>> I was wondering if this is due to the server having a invalid server
>> cert?  If I go to this server in my browser, I get a "This server tried
>> to identify itself with invalid information".  Is there a way to ignore
>> this issue with Python?  Can I setup a trust store and add this server
>> to the trust store?
> 
> I don't see the point in trusting someone that you know is telling lies
> about itself.

Don't you? It's just commonsense risk assessment.

It's far more likely that the server has an incorrectly setup certificate 
managed by an incompetent sys admin than it is that somebody is eaves-
dropping on my connection to https://somerandom.site.com/something-trivial

Particularly when the connection is on my own intranet and I know the sys 
admin in question has made a mistake and the new certificate is scheduled 
to be installed "some time next week". *wink*

Of course, if there was sensitive information involved, or money, then 
I'd be more concerned.


-- 
Steven


From gherron at islandtraining.com  Mon Jul 27 19:06:36 2009
From: gherron at islandtraining.com (Gary Herron)
Date: Mon, 27 Jul 2009 16:06:36 -0700
Subject: initializing with empty list as default causes freaky problems
In-Reply-To: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
References: <a1c36130-a0e2-4b98-a531-abc82e249918@2g2000prl.googlegroups.com>
Message-ID: <4A6E32FC.4080202@islandtraining.com>

Reckoner wrote:
> Hi,
>
> Observe the following:
>
> In [202]: class Foo():
>    .....:     def __init__(self,h=[]):
>    .....:         self.h=h
>    .....:
>    .....:
>
> In [203]: f=Foo()
>
> In [204]: g=Foo()
>
> In [205]: g.h
> Out[205]: []
>
> In [206]: f.h
> Out[206]: []
>
> In [207]: f.h.append(10)
>
> In [208]: f.h
> Out[208]: [10]
>
> In [209]: g.h
> Out[209]: [10]
>
> The question is: why is g.h updated when I append to f.h?  Shouldn't
> g.h stay []?
>
> What am I missing here?
>
> I'm using Python 2.5.1.
>
> Thanks in advance.
>   

This is a FAQ (and *very* common newbie trap)!  See:

  
http://www.python.org/doc/faq/general/#why-are-default-values-shared-between-objects

Gary Herron



From drobinow at gmail.com  Mon Jul 27 19:07:06 2009
From: drobinow at gmail.com (David Robinow)
Date: Mon, 27 Jul 2009 18:07:06 -0500
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4kepl$qhf$1@panix3.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<h4gnmr$8cl$1@news.eternal-september.org>
	<4eb0089f0907261226q13cbfa8am9a52f35c471e44db@mail.gmail.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
Message-ID: <4eb0089f0907271607m1dd34f39qaec04a650afdd31f@mail.gmail.com>

On Mon, Jul 27, 2009 at 9:49 AM, Aahz<aahz at pythoncraft.com> wrote:
> In article <mailman.3765.1248685391.8015.python-list at python.org>,
> Hendrik van Rooyen ?<hendrik at microcorp.co.za> wrote:
>>On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>
>>> ?I'm a mediocre programmer. Does this mean I should switch to PHP?
>>
>>I have searched, but I can find nothing about this mediocre language.
>>
>>Could you tell us more?
>
> (For anyone who is confused by Hendrik's humor, he is saying that David
> was referring to a programming language named "mediocre". ?English
> grammar is confusing!)
 Well, Aahz, I think it rather rude to spoil the fun with your explanation.
Just for that, I'm not going to post any mediocre code. You'll have to
figure it out yourself.
(Q:   should the name of my favorite language be capitalized?)


From roy at panix.com  Mon Jul 27 19:21:43 2009
From: roy at panix.com (Roy Smith)
Date: Mon, 27 Jul 2009 19:21:43 -0400
Subject: Discovery IP in connection
References: <mailman.3797.1248726749.8015.python-list@python.org>
Message-ID: <roy-8412BB.19214327072009@news.panix.com>

In article <mailman.3797.1248726749.8015.python-list at python.org>,
 Djames Suhanko <djames.suhanko at gmail.com> wrote:

> Hello,all!
>  I wrote a little programa that listening UDP packets. A can receive
> the messages, but I can't see the the origin IP.
>  How can I to  get the remote IP address in connection?
> 
> My source:
> 
> #!/usr/bin/env python
> import socket
> mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
> mySocket.bind ( ( '', 514 ) )
> 
> data, addr = mySocket.recvfrom(100)
> print data

What happens when you print addr?


From piet at cs.uu.nl  Mon Jul 27 19:23:13 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 01:23:13 +0200
Subject: Discovery IP in connection
References: <mailman.3797.1248726749.8015.python-list@python.org>
Message-ID: <m2ws5taexq.fsf@cs.uu.nl>

>>>>> Djames Suhanko <djames.suhanko at gmail.com> (DS) wrote:

>DS> Hello,all!
>DS>  I wrote a little programa that listening UDP packets. A can receive
>DS> the messages, but I can't see the the origin IP.
>DS>  How can I to  get the remote IP address in connection?

What do you think the addr is for in 
data, addr = mySocket.recvfrom(100)?

>DS> My source:

>DS> #!/usr/bin/env python
>DS> import socket
>DS> mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
>DS> mySocket.bind ( ( '', 514 ) )

>DS> data, addr = mySocket.recvfrom(100)
>DS> print data

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From david.lyon at preisshare.net  Mon Jul 27 19:53:00 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Mon, 27 Jul 2009 19:53:00 -0400
Subject: Using =?UTF-8?Q?easy=5Finstall=2C=20reduncant=3F?=
In-Reply-To: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
References: <ce8d94e4-a526-46ef-9693-f20ae86669bb@2g2000prl.googlegroups.com>
Message-ID: <8ae7c63db1dfcc3bbc1619b67939a5d5@preisshare.net>

On Mon, 27 Jul 2009 09:42:06 -0700 (PDT), ray <Ray.Joseph at CDICorp.com>
wrote:
> I am working on a Trac installation.  I am new to Python.  To install
> packages, it is suggested to use setuptools.  I have not understood
> the directions.
> 
> I execute ez_install.py.
> 
> Then I attempt to execute easy_install.py setuptools-0.6c9-py2.6.egg.
> There response that setuptools is already the active version in easy-
> install.pth.  Then:
> Installing easy_install.exe script to C:\Python26\Scripts error:  C:
> \Python26\Scripts\Easy_install.exe: Permission denied.
> 
> I have compared the file entries before and after this attempt and
> there are no new files.  Is there any problems here?  What did I miss?

Try using python package manager :
http://sourceforge.net/projects/pythonpkgmgr/

You might find it a lot simpler. It will download and install setuptools
for you if you are still having problems.

David


From r1chardj0n3s at gmail.com  Mon Jul 27 20:34:52 2009
From: r1chardj0n3s at gmail.com (Richard Jones)
Date: Tue, 28 Jul 2009 10:34:52 +1000
Subject: Next meeting: Tuesday 11th August
Message-ID: <1680A969-5DD9-4A2C-BACB-9B342C44123C@gmail.com>

The next meeting of the Melbourne Python Users Group will be on  
Tuesday the 11th of August starting at 6:30pm. We'll be meeting at  
Horse Bazaar again but this time we'll have use of their projector.  
We'll have time for several short presentations or lightning talks.

Meeting details, location and talks list are at:

   http://wiki.python.org/moin/MelbournePUG

If you've seen something cool or are doing something cool then we'd  
like you to tell everyone about it! Presentations could be 5 minutes  
or up to 15 minutes if you'd like to ramble for a bit longer. I'll be  
getting up to talk a bit about my experiences playing with IronPython  
- what's cool and what's downright odd :)

If you've got an idea for a talk just add it to the wiki page.


     Richard



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 20:46:51 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 21:46:51 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<157f16f9-2172-4fd5-8ec8-8d9569a3f186@f20g2000prn.googlegroups.com>
Message-ID: <op.uxq5sdfcx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 15:52:08 -0300, jakecjacobson  
<jakecjacobson at gmail.com> escribi?:

> On Jul 27, 2:23?pm, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson ?
>> <jakecjacob... at gmail.com> escribi?:
>>
>> > I was wondering if this is due to the server having a invalid server
>> > cert? ?If I go to this server in my browser, I get a "This server
>> > tried to identify itself with invalid information". ?Is there a way to
>> > ignore this issue with Python? ?Can I setup a trust store and add this
>> > server to the trust store?
>>
>> I don't see the point in trusting someone that you know is telling lies  
>> about itself.
>
> It is a test box that the team I am on runs.  That is why I would
> trust it.

I'd fix the certificate issue on the server. Or use plain HTTP if it's  
just for testing.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:16:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:16:39 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <op.uxq6brfjx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 20:00:27 -0300, Steven D'Aprano
<steve at remove-this-cybersource.com.au> escribi?:
> On Mon, 27 Jul 2009 15:23:41 -0300, Gabriel Genellina wrote:
>> En Mon, 27 Jul 2009 12:57:40 -0300, jakecjacobson
>> <jakecjacobson at gmail.com> escribi?:
>>
>>> I was wondering if this is due to the server having a invalid server
>>> cert?  If I go to this server in my browser, I get a "This server tried
>>> to identify itself with invalid information".  Is there a way to ignore
>>> this issue with Python?  Can I setup a trust store and add this server
>>> to the trust store?
>>
>> I don't see the point in trusting someone that you know is telling lies
>> about itself.
>
> Don't you? It's just commonsense risk assessment.
>
> It's far more likely that the server has an incorrectly setup certificate
> managed by an incompetent sys admin than it is that somebody is eaves-
> dropping on my connection to  
> https://somerandom.site.com/something-trivial

Fire the sys admin then :)
I don't see the point on "fixing" either the Python script or httplib to
accomodate for an invalid server certificate... If it's just for internal
testing, I'd use HTTP instead (at least until the certificate is fixed).

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:16:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:16:42 -0300
Subject: Download the "head" of a large file?
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
	<5579245f-b8cb-44cc-9b5f-1e7009422a58@g19g2000vbi.googlegroups.com>
Message-ID: <op.uxq7lqixx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 19:40:25 -0300, John Yeung
<gallium.arsenide at gmail.com> escribi?:

> On Jul 27, 4:38?pm, erikcw <erikwickst... at gmail.com> wrote:
>> I'm trying to figure out how to download just the first few lines of a
>> large (50mb) text file form a server to save bandwidth. ?Can Python do
>> this?
>>
>> Something like the Python equivalent of curlhttp://url.com/file.xml|
>> head -c 2048
>
> urllib.urlopen gives you a file-like object, which you can then read
> line by line or in fixed-size chunks.  For example:
>
> import urllib
> chunk = urllib.urlopen('http://url.com/file.xml').read(2048)
>
> At that point, chunk is just bytes, which you can write to a local
> file, print, or whatever it is you want.

As the OP wants to save bandwidth, it's better to ask exactly the amount
of data to read. That is, add a Range header field [1] to the request, and
inspect the response for a corresponding Content-Range header [2].

py> import urllib2
py> url = "http://www.python.org/"
py> req = urllib2.Request(url)
py> req.add_header('Range', 'bytes=0-10239')  # first 10K
py> f = urllib2.urlopen(req)
py> data = f.read()
py> print repr(data[-30:]), len(data)
'\t    <a href="http://www.zope.' 10240
py> f.headers['Content-Range']
'bytes 0-10239/18196'
py> f.getcode()
206            # 206=Partial Content
py> f.close()

[1] http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35

[2] http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.16

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:16:48 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:16:48 -0300
Subject: ioctl on socket
References: <h4knsn$u76$1@lec.cs.unibo.it>
Message-ID: <op.uxq8xesrx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 16:35:51 -0300, jacopo mondi <mondi at cs.unibo.it>
escribi?:

> Is there a reason why there is no ioctl interface for socket either then
> for windows platform? It's technical issues or what else??

I don't completely understand your question. On Windows, you can use
socket.ioctl with sockets, and DeviceIoControl (from the pywin32 package)
with other files. On Linux, you have fcntl.ioctl that works with any kind
of file.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Mon Jul 27 22:17:18 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Mon, 27 Jul 2009 23:17:18 -0300
Subject: where do I put resources (images, audio files) when I wrote
	Python program?
References: <h4ksgo$qa9$1@inews.gazeta.pl> <4A6E13B8.4080806@ieee.org>
Message-ID: <op.uxq8a1g6x6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 17:53:12 -0300, Dave Angel <davea at ieee.org> escribi?:
> Piotrek wrote:
>>
>> I write a Python program. It will contain some images (in .png format),  
>> some
>> audio files (as .ogg) etc. Now I think where should my installer put  
>> these
>> files and how should I access them. What is the normal Python way of  
>> doing
>> that? I think about puting these files in /usr/share/myprogram and then
>> reading it the normal way (so the path "/usr/share/myprogram" would be  
>> just
>> hardwired in my program). Is it the way one usually does it in Python
>> program or is there any more sofisticated way?
>>
>>
> My answer is to put read-only files right with the py* files, and  
> writable files in the user's space.  In the former case, you can find  
> the files by parsing __file__ for one of your modules.  In the latter  
> case, it's system dependent.

For those read-only resources I'd use pkgutil.get_data (instead of
manually parsing __file__):

http://docs.python.org/library/pkgutil.html#pkgutil.get_data

It's easier to manage when someone later decide to install the package as
an egg file, or distribute it using py2exe. Quoting the documentation:

"""The function returns a binary string that is the contents of the
specified resource.

For packages located in the filesystem, which have already been imported,
this is the rough equivalent of:

d = os.path.dirname(sys.modules[package].__file__)
data = open(os.path.join(d, resource), 'rb').read()
return data
"""

-- 
Gabriel Genellina



From doug.farrell at gmail.com  Mon Jul 27 22:52:01 2009
From: doug.farrell at gmail.com (writeson)
Date: Mon, 27 Jul 2009 19:52:01 -0700 (PDT)
Subject: Extract images from PDF files
Message-ID: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>

Hi all,

I've looked around with Google quite a bit, but haven't found anything
like what I'm looking for. Is there a Python library that will extract
images from PDF files? My ultimate goal is to pull the images out, use
the PIL library to reduce the size of the images and rebuild another
PDF file that's an essentially "thumbnail" version of the original PDF
file, smaller in size.

We've been using imagick to extract the images, but it's difficult to
script and slow to process the input PDF. Can someone suggest
something better?

Thanks in advance,
Doug


From aahz at pythoncraft.com  Mon Jul 27 22:52:26 2009
From: aahz at pythoncraft.com (Aahz)
Date: 27 Jul 2009 19:52:26 -0700
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <h4lp5a$ehd$1@panix3.panix.com>

In article <mailman.3787.1248712420.8015.python-list at python.org>,
MRAB  <python at mrabarnett.plus.com> wrote:
>
>I've been working on a new implementation of the re module. The details
>are at http://bugs.python.org/issue2636, specifically from
>http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>Python 2.6 on Windows if you want to try it out.

How does it handle the re module's unit tests?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From dmw at coder.cl  Mon Jul 27 23:02:47 2009
From: dmw at coder.cl (Daniel Molina Wegener)
Date: Mon, 27 Jul 2009 23:02:47 -0400
Subject: [ANN] pyxser-1.1r --- python xml serialization
Message-ID: <u5KdnZcPYu0_9_PXnZ2dnUVZ_hydnZ2d@giganews.com>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

Hello,

I'm pleased to announce pyxser-1.1r, a Python-Object to XML
serializer and deserializer. This package it's completly
written in C and licensed under LGPLv3.

The tested Python versions are 2.5.X and 2.7.X.

* home page:
  http://coder.cl/software/pyxser

* hosted at:
  http://sourceforge.net/projects/pyxser/

The current ChangeLog is as follows:

- -----8<----------8<----------8<----------8<-----
1.1r (2009.05.09):

        Daniel Molina Wegener <dmw at coder.cl>
        * Removed bugs concerning XML schema declaration for output
        documents.
        * Removed bugs concerning XML schema design for C14N
        serialization.
        * Removed exc argument from C14N serialization functions,
        because they have no sense.
        * Code cleanup with function arguments (C code).
        * All changes seems to be transparent for previous versions.
- -----8<----------8<----------8<----------8<-----

Also, I need a little bit of feedback. I want it to be able to
serialize files and buffers: I've planned to allow the user
to have three options: ignore files, serialize them in base64
encoding and just put the file name as string. But my question
concerns how the files and buffers are deserialized: I must
allow the user to dump the files on a directory, put the complete
file on a buffer object, or just extract the base64 encoded
block?

Best regards and thanks in advance...
- -- 
 .O. | Daniel Molina Wegener   | FreeBSD & Linux
 ..O | dmw [at] coder [dot] cl | Open Standards
 OOO | http://coder.cl/        | FOSS Developer

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (FreeBSD)
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=7sXN
-----END PGP SIGNATURE-----


From huzaigang at cn.panasonic.com  Mon Jul 27 23:06:06 2009
From: huzaigang at cn.panasonic.com (jammy)
Date: Tue, 28 Jul 2009 11:06:06 +0800
Subject: How to get the output struct parameter by extending C function?
Message-ID: <006a01ca0f30$59849b30$af97c20a@psdcd.local>

Hello,

I an just starting to use the ctypes module.
Now I want to expentd C in python.
In the function of C, I want to get the  output struct parameter which 
is chaged in the function.
following is my code:

----------- 1.Header file of C?information.h?-----------
typedef struct {
 char  name[20];
 int   height;
 int   weight;
} Infor;
int getInfor( char* name, int height, int weight, Infor* infor);


----------- 2.Source file of C?information.c?-----------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "Extest.h"
int getInfor( char* name, int height, int weight, Infor* infor)
{
    if(name == NULL || infor == NULL)
        return (-1);

    printf("  [%s] get params: name[%s] height[%d] weight[%d]\n", 
__FUNCTION__, name, height, weight);
    strcpy(infor->name, name);
    infor->height = height;
    infor->weight = weight;
    return (1);
}


----------- 3.information.c's warp file for Python calling?information_wrap.c?----------- 

#include "Python.h"
#include "ceval.h"
#include "Extest.h"

static PyObject * Extest_getInfor(PyObject *self, PyObject *args)
{
    char* name;
    int height;
    int weight;
    Infor* infor;
    int res;

    if(!PyArg_ParseTuple(args, "siiO:infor", &name, &height, &weight, 
&infor)){
         return NULL;
    }

    printf(" ***** Before Call: infor.name[%s] infor.height[%d] 
infor.weight[%d] *****\n",infor->name, infor->height, 
infor->weight);//[1]initial value
    res = getInfor(name, height, weight, infor);
    printf(" ***** After Call: infor.name[%s] infor.height[%d] 
infor.weight[%d] *****\n", infor->name, infor->height, 
infor->weight);//[2]changed value

    return (PyObject*)Py_BuildValue("i", res);
}

static PyMethodDef ExtestMethods[] = {
    { "getInfor", Extest_getInfor, METH_VARARGS },
    { NULL, NULL },
};

void initExtest(void)
{
    PyObject *m;
    m = Py_InitModule("Extest", ExtestMethods);
}


----------- 4.Makefile-----------
# Makefile of Extend C for Python
OBJS          = Extest.o ExtestWrappers.o
TARGET      = Extest.so
INCLUDES   = -I /usr/local/include/python2.6/
MAKEFILE   = Makefile
CC             = gcc
CFLAGS      = -fPIC -Wall -Wstrict-prototypes -Winline \
                    ${INCLUDES} -O2
all : ${TARGET}
${TARGET} : ${OBJS} ${LIBS}
    ${CC} -shared -o ${TARGET} ${OBJS}
    rm -f ${OBJS}
clean :
    rm -f *.o *.Z* *~ ${TARGET}


----------- 5.test file of Python?test.py?-----------
#!/usr/bin/env python2.6
#coding=utf8

import Extest
from ctypes import *

class Infor(Structure):
    _fields_= [('name', c_char*20),
    ('height', c_int),
    ('weight', c_int)]

def main():
    infor = Infor()
    infor.name = 'NoName'
    infor.height = -1
    infor.weight = -1

    name = 'TestName'
    height = 175
    weight = 160

    print 'Before call getInfor(), Infor.name=%s  Infor.height=%d 
Infor.weight=%d' % (infor.name, infor.height, infor.weight)
    Extest.getInfor(name, height, weight, byref(infor))
    print 'After call getInfor(), Infor.name=%s  Infor.height=%d 
Infor.weight=%d' % (infor.name, infor.height, infor.weight) [3]want to 
get value of infor changed
    print ' ----- all DONE -----'

if __name__ == '__main__':
    main()

----------- 6.result of running test.py -----------
[root at localhost obj_struct_test]# ./test.py
Before call getInfor(), Infor.name=NoName  Infor.height=-1 
Infor.weight=-1
sizeof(*infor)=28, sizeof(Infor)=28
        ***** [Extest_getInfor] Before Call: infor.name[] 
infor.height[0] infor.weight[0] *****
                [getInfor] get params: name[TestName] height[175] 
weight[160]
        ***** [Extest_getInfor] After Call: infor.name[TestName] 
infor.height[175] infor.weight[160] *****
After call getInfor(), Infor.name=NoName  Infor.height=-1 
Infor.weight=-1
 ----- all DONE -----

Looking for the printed information, in the file of 
information_wrap.c(setp 3), In the comment 's tag[2], printed value is 
changed valuse.
Why  is the printed Information initial value atfer calling getInfor() 
in test.py?
Thanks for your help!

                                                                       
                       yours: jammy 



From mobiledreamers at gmail.com  Mon Jul 27 23:31:25 2009
From: mobiledreamers at gmail.com (mobiledreamers at gmail.com)
Date: Mon, 27 Jul 2009 20:31:25 -0700
Subject: [Baypiggies] Egnyte: hiring
In-Reply-To: <20090728024611.GA4649@panix.com>
References: <20090728024611.GA4649@panix.com>
Message-ID: <c1870d60907272031i2413f84bu2b00cb52ba2a8cac@mail.gmail.com>

Seems interesting
http://fotoroll.com/searchvideo?q=vineet%20jain,%20ceo%20of%20egnyte&id=0&type=video

<http://fotoroll.com/searchvideo?q=vineet%20jain,%20ceo%20of%20egnyte&id=0&type=video>

On Mon, Jul 27, 2009 at 7:46 PM, Aahz <aahz at pythoncraft.com> wrote:

> My new company (I just started today) closed a big venture capital round
> (also today) and is looking to hire more people, preferably with Python
> experience:
>
> Senior Linux Engineer:
> http://sfbay.craigslist.org/pen/sof/1292008176.html
>
> Senior Platforms Engineer:
> http://sfbay.craigslist.org/pen/sof/1291776907.html
>
> Venture announcement:
> http://blogs.zdnet.com/BTL/?p=21777
>
> I can't say a lot about the company myself yet, but I've gotten a good
> impression of the team and the business plan.  Find out more here:
> http://www.egnyte.com/
> --
> Aahz (aahz at pythoncraft.com)           <*>
> http://www.pythoncraft.com/
>
> "Many customs in this life persist because they ease friction and promote
> productivity as a result of universal agreement, and whether they are
> precisely the optimal choices is much less important." --Henry Spencer
> _______________________________________________
> Baypiggies mailing list
> Baypiggies at python.org
> To change your subscription options or unsubscribe:
> http://mail.python.org/mailman/listinfo/baypiggies
>



-- 
Bidegg worlds best auction site
http://bidegg.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090727/04e3e280/attachment-0001.html>

From david.lyon at preisshare.net  Mon Jul 27 23:37:39 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Mon, 27 Jul 2009 23:37:39 -0400
Subject: Extract images from PDF files
In-Reply-To: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
Message-ID: <e55aa5912cc63888ddc2f52c8404bbe2@preisshare.net>


pdftohtml on sourceforge may help...

On Mon, 27 Jul 2009 19:52:01 -0700 (PDT), writeson <doug.farrell at gmail.com>
wrote:
> Hi all,
> 
> I've looked around with Google quite a bit, but haven't found anything
> like what I'm looking for. Is there a Python library that will extract
> images from PDF files? My ultimate goal is to pull the images out, use
> the PIL library to reduce the size of the images and rebuild another
> PDF file that's an essentially "thumbnail" version of the original PDF
> file, smaller in size.
> 
> We've been using imagick to extract the images, but it's difficult to
> script and slow to process the input PDF. Can someone suggest
> something better?
> 
> Thanks in advance,
> Doug


From himanshu.garg at gmail.com  Tue Jul 28 00:22:29 2009
From: himanshu.garg at gmail.com (++imanshu)
Date: Mon, 27 Jul 2009 21:22:29 -0700 (PDT)
Subject: _msi.Record object has no attribute 'GetString'
References: <32e0b242-8635-40b5-a366-2c9967e64e1c@d4g2000yqa.googlegroups.com>
Message-ID: <2392afa6-59fe-4c98-8c12-403222a8ee24@a37g2000prf.googlegroups.com>

On Jul 27, 4:38?pm, "++imanshu" <himanshu.g... at gmail.com> wrote:
> The documentation (http://docs.python.org/library/msilib.html#record-
> objects) for msilib mentions the GetString() method on Record objects.
> However, the following snippet :-
>
> db = msilib.OpenDatabase(os.path.join(root, file),
> msilib.MSIDBOPEN_READONLY)
> view = db.OpenView('SELECT * FROM Property')
> view.Execute(None)
> r = view.Fetch()
> print dir(r)
> print r.GetString(0)
>
> gives me this error :-
>
> c:\>python msi.py
> ['ClearData', 'GetFieldCount', 'SetInteger', 'SetStream', 'SetString',
> __class__', '__delattr__', '__doc__', '__getattribute__', '__hash__',
> '__init__', '__new__', __reduce__', '__reduce_ex__', '__repr__',
> '__setattr__', '__str__']
> Traceback (most recent call last):
> ? File "msi.py", line 18, in <module>
> ? ? print r.GetString(0)
> AttributeError: '_msi.Record' object has no attribute 'GetString'
>
> Am I missing something?

Known Issue. Already fixed here http://mail.python.org/pipermail/python-bugs-list/2008-February/047136.html



From gagsl-py2 at yahoo.com.ar  Tue Jul 28 00:34:42 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 01:34:42 -0300
Subject: How to get the output struct parameter by extending C function?
References: <006a01ca0f30$59849b30$af97c20a@psdcd.local>
Message-ID: <op.uxrgb4fax6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 00:06:06 -0300, jammy <huzaigang at cn.panasonic.com>  
escribi?:

> I an just starting to use the ctypes module.
> Now I want to expentd C in python.
> In the function of C, I want to get the  output struct parameter which  
> is chaged in the function.

You're mixing a C extension with a ctypes call - why is that?
ctypes is mainly used when you *don't* want to actually write a C  
extension - if you actually write one, you don't need ctypes at all.

> ----------- 1.Header file of C(information.h)-----------
> typedef struct {
>  char  name[20];
>  int   height;
>  int   weight;
> } Infor;
> int getInfor( char* name, int height, int weight, Infor* infor);

> ----------- 5.test file of Python(test.py)-----------
>     Extest.getInfor(name, height, weight, byref(infor))

All arguments for a function intended to be called from Python must be  
PyObject*; byref is used to call a ctypes-wrapped function, not a function  
 from an extension module. (You're lucky you didn't crash the interpreter  
process)

Either use ctypes to directly call the getInfor function in information.c  
(and drop the extension module), or write a complete wrapper in the  
extension module and forget ctypes. Don't mix both ways.

-- 
Gabriel Genellina



From doron.tal.list at gmail.com  Tue Jul 28 00:37:35 2009
From: doron.tal.list at gmail.com (Doron Tal)
Date: Tue, 28 Jul 2009 07:37:35 +0300
Subject: Gracefully exiting CLI application
In-Reply-To: <op.uxqxppj9fvx12t@jerzozwiesz.home.aster.pl>
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
	<873a8h4xf3.fsf@benfinney.id.au>
	<op.uxqxppj9fvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <2a8674c60907272137u6df107b7v25c73d0e4a8a9821@mail.gmail.com>

On Tue, Jul 28, 2009 at 12:52 AM, Jan Kaliszewski <zuo at chopin.edu.pl> wrote:

> As I wrote, you must use signals. Though sometimes it's a good idea
> to combine these two techniques (i.e. signal handlers call sys.exit(),
> then sys.exitfunc/or function registered with atexit does the actual
> cleaning actions).


Another way of combining signals and atexit functions is to write a signal
handlers which update some QUIT_APP flag, which the application polls on
occasionally. This way you'll avoid deadlocks which may happen if you have a
multi-threaded application, and your main thread had just acquired a lock.

--doron
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/1dd4b317/attachment-0001.html>

From brenNOSPAMbarn at NObrenSPAMbarn.net  Tue Jul 28 00:41:34 2009
From: brenNOSPAMbarn at NObrenSPAMbarn.net (OKB (not okblacke))
Date: Tue, 28 Jul 2009 04:41:34 GMT
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <Xns9C55DCA902C61OKB@199.45.49.11>

MRAB wrote:

> http://bugs.python.org/issue2636#msg90954

    	Variable-length lookbehind!  My hero!

-- 
--OKB (not okblacke)
Brendan Barnwell
"Do not follow where the path may lead.  Go, instead, where there is
no path, and leave a trail."
	--author unknown


From janssen at parc.com  Tue Jul 28 01:45:23 2009
From: janssen at parc.com (Bill Janssen)
Date: Mon, 27 Jul 2009 22:45:23 PDT
Subject: new version of SSL module on PyPI
Message-ID: <2029.1248759923@parc.com>

I've uploaded ssl-1.15.tgz, the backport of the 2.6/3.x SSL module to
Python 2.3-2.5.  It provides an option for not using SSLv2, and also
fixes a bug with write retries.

Bill


From hekevintran at gmail.com  Tue Jul 28 02:02:30 2009
From: hekevintran at gmail.com (Kevin)
Date: Mon, 27 Jul 2009 23:02:30 -0700 (PDT)
Subject: Error in compiling Python on OS X
References: <2a083a20-ec25-4533-aa47-8a4330655ba4@o9g2000prg.googlegroups.com>
	<7d44lbF29p3p7U1@mid.uni-berlin.de>
Message-ID: <5535080f-30ba-473c-8710-8752bf745e70@p36g2000prn.googlegroups.com>

On Jul 26, 3:46?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Kevin schrieb:
>
> > I am trying to compile Python 2.6.2 on Mac OS X 10.5.7. ?I have Xcode
> > 3.1.3 installed.
>
> > The error I got is below.
>
> > $ ./configure --prefix=/Users/me/python
>
> Use a framework-build.
>
> > checking for --with-universal-archs... 32-bit
> > checking MACHDEP... darwin
> > checking EXTRAPLATDIR... $(PLATMACDIRS)
> > checking machine type as reported by uname -m... i386
> > checking for --without-gcc... no
> > checking for gcc... gcc
> > checking for C compiler default output file name...
> > configure: error: C compiler cannot create executables
> > See `config.log' for more details.
>
> > Please send any ideas.
>
> What happens if you write a simple test.c like this:
>
> int main() {
> ? ? return 0;
>
> }
>
> and compile it with gcc on the commandline? There must be a file called
> "a.out" afterwards.
>
> diez

I have solved my problem.  I think something was wrong with my
compiler.  After I installed Xcode again, I was able to compile with
no problems.


From bcharrow at csail.mit.edu  Tue Jul 28 02:18:37 2009
From: bcharrow at csail.mit.edu (Ben Charrow)
Date: Tue, 28 Jul 2009 02:18:37 -0400
Subject: Download the "head" of a large file?
In-Reply-To: <h4m3pc$q7m$1@ger.gmane.org>
References: <8f80931b-eb54-434f-9f80-a8eea90f3c67@y28g2000prd.googlegroups.com>
	<h4m3pc$q7m$1@ger.gmane.org>
Message-ID: <4A6E983D.20707@csail.mit.edu>

Dennis Lee Bieber wrote:
> On Mon, 27 Jul 2009 13:38:25 -0700 (PDT), erikcw
> <erikwickstrom at gmail.com> declaimed the following in
> gmane.comp.python.general:
>> Something like the Python equivalent of curl http://url.com/file.xml |
>> head -c 2048
>>
> 	Presuming that | is a shell pipe operation, then doesn't that
> command line use "curl" to download the entire file, and "head" to
> display just the first 2k?

No, the entire file is not downloaded.  My understanding of why this is (which 
could be wrong) is that the output of curl is piped to head, and once head gets 
the first 2k it closes the pipe.  Then, when curl tries to write to the pipe 
again, it gets sent the SIGPIPE signal at which point it exits.

Cheers,
Ben


From paul.paj at gmail.com  Tue Jul 28 02:21:10 2009
From: paul.paj at gmail.com (Paul Johnston)
Date: Mon, 27 Jul 2009 23:21:10 -0700 (PDT)
Subject: Determining __name__ from the code that called a function
Message-ID: <edf221e9-3538-4d84-8a6f-28074b567fdb@x5g2000prf.googlegroups.com>

Hi,

In ToscaWidgets 2 experimental, when defining resources you often do
something like this:
CSSLink(modname=__name__, filename='static/mycss.css')

Now, what I'd like to do is make the "modname=__name__" optional, to
make code more concise. I figure there must be some way (using inspect
or something) to determine what __name__ would be in the code that
just called my function. Couldn't immediately see how to do this - any
suggestions? Thanks,

Paul


From gagsl-py2 at yahoo.com.ar  Tue Jul 28 02:45:52 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 03:45:52 -0300
Subject: What is file.encoding convention?
References: <4468e223-564d-4c1f-8cd9-5338230f649a@12g2000pri.googlegroups.com>
	<2373a886-d577-4eab-8c8f-59acb92966e8@s31g2000yqs.googlegroups.com>
	<784cbf1c-db1b-4ced-8a80-8633ae943755@b15g2000yqd.googlegroups.com>
Message-ID: <op.uxrmeqdox6zn5v@lepton.softlabbsas.com.ar>

En Thu, 23 Jul 2009 21:49:26 -0300, Naoki INADA <songofacandy at gmail.com>  
escribi?:


>>> The encoding that this file uses. When Unicode strings are written to  
>>> a file,
>>>  they will be converted to byte strings using this encoding. In  
>>> addition,
>>> when the file is connected to a terminal, the attribute gives the  
>>> encoding
>>> that the terminal is likely to use
>
> I feel this doc means "file object with encoding attribute encodes
> unicode
> regardless it is tty or not" and sys.stdout/stderr defies convention.

The 'encoding' file attribute is very confusing and mostly unsupported (or  
there is a bug in the documentation, at least in Python 2.x). See  
http://bugs.python.org/issue4947

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Tue Jul 28 02:46:00 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 03:46:00 -0300
Subject: exceptions.TypeError an integer is required
References: <2b77d02c-e219-49c2-9929-70099ba88872@f33g2000vbm.googlegroups.com>
	<0279f85d$0$5185$c3e8da3@news.astraweb.com>
	<8d03a739-7e45-49e1-b93d-6a396beed877@a37g2000prf.googlegroups.com>
Message-ID: <op.uxrmeyayx6zn5v@lepton.softlabbsas.com.ar>

En Mon, 27 Jul 2009 12:44:40 -0300, jakecjacobson  
<jakecjacobson at gmail.com> escribi?:
>
> You are quite correct in your statements.  My goal was not to make
> great code but something that I could quickly test.  My assumption was
> that the httplib.HTTPSConnection() would do the cast to int for me.
> As soon as I cast it to an int, I was able to get past that issue.

A few remarks that may help learning the language:

Note that Python is a strongly typed (and dynamic) language. All objects  
have a defined type: "443" is not the same thing as 443, and "2" + 2  
raises a TypeError.

If a function expects an integer, you must provide an integer (or  
something that at least "acts" as an integer; a string isn't  
"integer-alike" at all from Python's POV)

Also, you don't "cast" an object into another: the expression int("443")  
is a constructor, and it returns a new object (an integer) based upon its  
argument. (so it's quite different from, say, casting "short" to "unsigned  
short" in C, that only changes the way the compiler treats the same bytes  
in memory).

-- 
Gabriel Genellina



From guitarzero at gmail.com  Tue Jul 28 03:18:43 2009
From: guitarzero at gmail.com (guitarzero)
Date: Tue, 28 Jul 2009 00:18:43 -0700 (PDT)
Subject: WSDL and XML generation
Message-ID: <3be39c48-6a89-4542-b08a-eaf00933b184@c1g2000yqi.googlegroups.com>

Hi all
Newbie in Python, i am looking for some pointers (or better existing
modules) to do the followings:

- generate (correct) XML messages from a WSDL file
- make some modifications inside XML messages *before* sending them to
the server hosting the Web services (described by previously
mentionned WSDL file)
- parse the answer.

Some ideas ?
Thanks in advance
Stephane


From oripel at gmail.com  Tue Jul 28 03:23:10 2009
From: oripel at gmail.com (orip)
Date: Tue, 28 Jul 2009 00:23:10 -0700 (PDT)
Subject: Testoob: How do you use testoob.collector_from_globals / 
	collector_from_modules?
References: <1a8582cc-a7fc-4b1e-b1b2-d23e20ad6022@18g2000yqa.googlegroups.com>
Message-ID: <0972bcba-a18c-4e33-9605-8955f723bd51@d32g2000yqh.googlegroups.com>

Hi Harry,

I forwarded this to the Testoob list at http://groups.google.com/group/testoob

Ori.

On Jul 27, 4:12?pm, Harry Ebbers <neme... at gmail.com> wrote:
> Hi,
>
> For a project I'm creating unittests using testoob. When all tests are
> in a single file there is no problem
>
> if __name__ == '__main__':
> ? ? testoob.main()
> ?does the trick as usual.
>
> But for a number of python-applications they have asked me to group
> unittests in different files, based on common functionality (e.g. GUI,
> main-application, etcetera).
>
> Ican get it to work by importing all unittestclasses in the following
> way and than use the normal if __name__ == '__main__' construction
>
> (from GUI import GUItests
> from APP import APPtests
>
> if __name__ == '__main__':
> ? ? testoob.main())
>
> But looking at the future I would like to use testsuites.
>
> On the internet I found the functions testoob.collector_from_globals
> and collector_from_modules which one can use to 'easily' create
> testsuites which can be used with testoob. But no examples on how to
> use them can be found.
>
> Can anybody supply me with a working example?
>
> TIA
>
> Harry Ebbers



From nick at craig-wood.com  Tue Jul 28 03:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Tue, 28 Jul 2009 02:29:56 -0500
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
Message-ID: <slrnh6t7lt.o4a.nick@irishsea.home.craig-wood.com>

jakecjacobson <jakecjacobson at gmail.com> wrote:
>  I am getting the following error when doing a post to REST API,
> 
>  Enter PEM pass phrase:
>  Traceback (most recent call last):
>    File "./ices_catalog_feeder.py", line 193, in ?
>      main(sys.argv[1])
>    File "./ices_catalog_feeder.py", line 60, in main
>      post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
>  (input_dir, file), collection_name, key_file, cert_file)
>    File "./ices_catalog_feeder.py", line 125, in post2Catalog
>      connection.request('POST', path, parameters, head)
>    File "/usr/lib/python2.4/httplib.py", line 810, in request
>      self._send_request(method, url, body, headers)
>    File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
>      self.endheaders()
>    File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
>      self._send_output()
>    File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
>      self.send(msg)
>    File "/usr/lib/python2.4/httplib.py", line 652, in send
>      self.connect()
>    File "/usr/lib/python2.4/httplib.py", line 1079, in connect
>      ssl = socket.ssl(sock, self.key_file, self.cert_file)
>    File "/usr/lib/python2.4/socket.py", line 74, in ssl
>      return _realssl(sock, keyfile, certfile)
>  socket.sslerror: (1, 'error:14094412:SSL
>  routines:SSL3_READ_BYTES:sslv3 alert bad certificate')
> 
> 
>  My code where this error occurs is:
> 
>  head = {"Content-Type" : "application/x-www-form-urlencoded",
>  "Accept" : "text/plain"}
>  parameters = urlencode({"collection" : collection, "entryxml" : open
>  (file,'r').read()})
>  print "Sending the file to: " + host
> 
>  try:
>  	try:
>  		# Default port is 443.
>  		# key_file is the name of a PEM formatted file that contains your
>  private key.
>  		# cert_file is a PEM formatted certificate chain file.
>  		connection = httplib.HTTPSConnection(host, int(port), key_file,
>  cert_file)
>  		connection.request('POST', path, parameters, head)
>  		response = connection.getresponse()
>  		print response.status, response.reason
>  	except httplib.error, (value,message):
>  		print value + ':' + message
>  finally:
>  	connection.close()
> 
>  I was wondering if this is due to the server having a invalid server
>  cert?

I'd say judging from the traceback you messed up key_file or cert_file
somehow.

Try using the openssl binary on them (read the man page to see how!)
to check them out.

>  If I go to this server in my browser, I get a "This server tried to
>  identify itself with invalid information".  Is there a way to
>  ignore this issue with Python?  Can I setup a trust store and add
>  this server to the trust store?

Invalid how?  Self signed certificate? Domain mismatch? Expired certificate?

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From mal at egenix.com  Tue Jul 28 03:30:23 2009
From: mal at egenix.com (M.-A. Lemburg)
Date: Tue, 28 Jul 2009 09:30:23 +0200
Subject: RSA cryptography between Python and Java
In-Reply-To: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
References: <q3zr5w4wpxo.fsf@antonio.tmnwh.net>
Message-ID: <4A6EA90F.1030000@egenix.com>

Rob Knop wrote:
> I've created an RSA key in Java.  I have exported the public key by
> making it into a X509EncodedKeySpec and spitting out the result of
> getEncoded().
> 
> I want to use this public key to encode something in python that I will
> send to Java, and then decode in Java with the corresponding private
> key.
> 
> Are there any python libraries that will take a public key in this
> format and do RSA encoding on it?

M2Crypto will let you do this:

    http://chandlerproject.org/bin/view/Projects/MeTooCrypto

If you have access to the raw key data (instead of having it
encoded in a X509 certificate), then you can also use PyCrypto,
which does require setting up OpenSSL first:

    http://www.dlitz.net/software/pycrypto/

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Jul 28 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/


From gagsl-py2 at yahoo.com.ar  Tue Jul 28 03:40:03 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 04:40:03 -0300
Subject: Determining __name__ from the code that called a function
References: <edf221e9-3538-4d84-8a6f-28074b567fdb@x5g2000prf.googlegroups.com>
Message-ID: <op.uxrow1sbx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 03:21:10 -0300, Paul Johnston <paul.paj at gmail.com>  
escribi?:

> In ToscaWidgets 2 experimental, when defining resources you often do
> something like this:
> CSSLink(modname=__name__, filename='static/mycss.css')
>
> Now, what I'd like to do is make the "modname=__name__" optional, to
> make code more concise. I figure there must be some way (using inspect
> or something) to determine what __name__ would be in the code that
> just called my function. Couldn't immediately see how to do this - any
> suggestions?

In CPython, you may use sys._getframe(1).f_globals['__name__'] but I don't  
know how portable is that across Python implementations.

-- 
Gabriel Genellina



From marco at sferacarta.com  Tue Jul 28 04:18:57 2009
From: marco at sferacarta.com (Marco Mariani)
Date: Tue, 28 Jul 2009 10:18:57 +0200
Subject: where do I put resources (images, audio files) when I wrote Python
	program?
In-Reply-To: <h4ksgo$qa9$1@inews.gazeta.pl>
References: <h4ksgo$qa9$1@inews.gazeta.pl>
Message-ID: <Svybm.564$I16.98@tornado.fastwebnet.it>

Piotrek wrote:

> that? I think about puting these files in /usr/share/myprogram and then
> reading it the normal way (so the path "/usr/share/myprogram" would be just
> hardwired in my program). Is it the way one usually does it in Python
> program or is there any more sofisticated way?

Just keep them in your sources, and create an empty __init__.py file in 
the images directory.
Then install setuptools and use the pkg_resources module. It will work 
even if your application is installed as an egg through easy_install, 
possibly zipped.


To open a resource file:

f = pkg_resources.resource_stream('path.to.package', 'resource.png')
f.read()


"""
     Return a readable file-like object for the specified resource; it 
may be an actual file, a StringIO, or some similar object. The stream is 
in "binary mode", in the sense that whatever bytes are in the resource 
will be read as-is.
"""


From niklasro at gmail.com  Tue Jul 28 04:26:57 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 01:26:57 -0700 (PDT)
Subject: The longest word
Message-ID: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>

Newbie hello onwards to the .py manual asks meantime how the longest
word gets determined?
First word, ok
 'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
'a'
rfind is another subset
>>> 'a aa aaa aa'[:'a aa aaa aa'.rfind(' ',1,10)]
'a aa aaa'
One row should be able. It's a direct word 'a aa aaa...' and can be a
variable, it's no big deal it occurs twice still naturally easier if
also occured just once.
Sincere thanks & regards
Niklas


From hendrik at microcorp.co.za  Tue Jul 28 04:35:48 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Tue, 28 Jul 2009 10:35:48 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4kepl$qhf$1@panix3.panix.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
Message-ID: <200907281035.48713.hendrik@microcorp.co.za>

On Monday 27 July 2009 16:49:25 Aahz wrote:
> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>
> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
> >On Sunday 26 July 2009 21:26:46 David Robinow wrote:
> >>  I'm a mediocre programmer. Does this mean I should switch to PHP?
> >
> >I have searched, but I can find nothing about this mediocre language.
> >
> >Could you tell us more?
> >
> :-P
>
> (For anyone who is confused by Hendrik's humor, he is saying that David
> was referring to a programming language named "mediocre".  English
> grammar is confusing!)

This is true - I intended, when I started the post, to make a crack about
how he knew that he was mediocre - If there were some exam or test
that you have to pass or fail to be able to make the claim to mediocrity.
I was imagining a sort of devil's rating scale for programmers, that
could cause one to say things like:  "I am studying hard so that I can
get my mediocre certificate, and one day I hope to reach hacker rank".

And then the similarity to "I am a COBOL programmer" struck me, 
and I abandoned the ratings.

- Hendrik



From bearophileHUGS at lycos.com  Tue Jul 28 05:02:23 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Tue, 28 Jul 2009 02:02:23 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
Message-ID: <99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>

On Jul 28, 10:26?am, NiklasRTZ <nikla... at gmail.com> wrote:
> Newbie hello onwards to the .py manual asks meantime how the longest
> word gets determined?
> First word, ok
> ?'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]

Your language is not easy to understand, but I think you want to find
the longest word in a string.
If this is the input string:
txt = "a aa aaa aa"

There are several ways to do it, I'll show a simple one.

You can split it into its parts (not having Python a built-in lazy
split yet, you can split it all at once). You can do it with the
string split method. It produces a list of the words, more or less
(but you may have words like "gone,", you may have to take care of
them too, this requires some code.

Once you have a list of words, you have to take the longest. A simple
way is to replace each word with a tuple that contains the length of
the word and the word itself, then pick the tuple with the highest
length value. But Python allows you to do such operation in a faster
way: you can use the max() function, it has a "key" function that
allows you to remap on the fly what you mean by "max". So you just
have to give it a function (reference) that given the word spits its
length, such function is "len" itself.

If you instead want to find the position of the longest word the
program gets a little longer. Ask if you need something different.

Bye,
bearophile


From niklasro at gmail.com  Tue Jul 28 05:22:53 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 02:22:53 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
Message-ID: <aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>

On Jul 28, 5:02?am, Bearophile <bearophileH... at lycos.com> wrote:
> On Jul 28, 10:26?am, NiklasRTZ <nikla... at gmail.com> wrote:
>
> > Newbie hello onwards to the .py manual asks meantime how the longest
> > word gets determined?
> > First word, ok
> > ?'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
>
> Your language is not easy to understand, but I think you want to find
> the longest word in a string.
> If this is the input string:
> txt = "a aa aaa aa"
>
> There are several ways to do it, I'll show a simple one.
>
> You can split it into its parts (not having Python a built-in lazy
> split yet, you can split it all at once). You can do it with the
> string split method. It produces a list of the words, more or less
> (but you may have words like "gone,", you may have to take care of
> them too, this requires some code.
>
> Once you have a list of words, you have to take the longest. A simple
> way is to replace each word with a tuple that contains the length of
> the word and the word itself, then pick the tuple with the highest
> length value. But Python allows you to do such operation in a faster
> way: you can use the max() function, it has a "key" function that
> allows you to remap on the fly what you mean by "max". So you just
> have to give it a function (reference) that given the word spits its
> length, such function is "len" itself.
>
> If you instead want to find the position of the longest word the
> program gets a little longer. Ask if you need something different.
>
> Bye,
> bearophile

Thank you. This seems to work:
sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
len(b))[-1]
'sdfsdfsdfsdf'


From piet at cs.uu.nl  Tue Jul 28 05:24:37 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 11:24:37 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
Message-ID: <m2r5w19n3e.fsf@cs.uu.nl>

>>>>> NiklasRTZ <niklasro at gmail.com> (N) wrote:

>N> Newbie hello onwards to the .py manual asks meantime how the longest
>N> word gets determined?
>N> First word, ok
>N>  'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
>N> 'a'
>N> rfind is another subset
>>>>> 'a aa aaa aa'[:'a aa aaa aa'.rfind(' ',1,10)]
>N> 'a aa aaa'
>N> One row should be able. It's a direct word 'a aa aaa...' and can be a
>N> variable, it's no big deal it occurs twice still naturally easier if
>N> also occured just once.
>N> Sincere thanks & regards
>N> Niklas

1. Is this homework?
2. It sounds very confusing. Are you trying to find the longest word in
   a series of words seperated by spaces? find and rfind will not help
   you much. You should start with var.split() if var contains the text.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From jeanmichel at sequans.com  Tue Jul 28 05:33:43 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 28 Jul 2009 11:33:43 +0200
Subject: Override a method but inherit the docstring
In-Reply-To: <c93175a3-e8fa-4e18-a10c-1516b72dcdb9@33g2000vbe.googlegroups.com>
References: <87r5wggm0y.fsf@benfinney.id.au>	<mailman.3774.1248703529.8015.python-list@python.org>
	<c93175a3-e8fa-4e18-a10c-1516b72dcdb9@33g2000vbe.googlegroups.com>
Message-ID: <4A6EC5F7.9090402@sequans.com>

Shai wrote:
> On Jul 27, 5:05 pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
> wrote:
>   
>> Ben Finney wrote:
>>     
>>> The docstring for ?FooGonk.frobnicate? is, intentionally, perfectly
>>> applicable to the ?BarGonk.frobnicate? method also. Yet in overriding
>>> the method, the original docstring is not associated with it.
>>>       
>> I've also tried within the python interpreter, and it can perfectly
>> solve docstring inheritance. So why would you explicitly assign
>> docstring to child methods ?
>>
>>     
>
> What do you mean by "can perfectly solve docstring inheritance" ?
>
> After the following,
>
> class Foo(object):
>     def foo(self):
>         "Frobber"
>         pass
>
> class Bar(Foo):
>     def foo(self):
>         pass
>
> help(Bar.foo) does not display "Frobber" on my interpreter.
>
>   
You're right. I must have made some dumb mistake. So interpreters do not 
solve docstring inheritance, Epydoc does.

JM


From piet at cs.uu.nl  Tue Jul 28 05:36:46 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 11:36:46 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>
Message-ID: <m2my6p9mj5.fsf@cs.uu.nl>

>>>>> NiklasRTZ <niklasro at gmail.com> (N) wrote:

>N> Thank you. This seems to work:
>N> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
>N> len(b))[-1]
>N> 'sdfsdfsdfsdf'

simpler:

sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '), key=len)[-1]
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From mondi at cs.unibo.it  Tue Jul 28 06:05:43 2009
From: mondi at cs.unibo.it (jacopo mondi)
Date: Tue, 28 Jul 2009 10:05:43 +0000
Subject: ioctl on socket
In-Reply-To: <mailman.3811.1248747906.8015.python-list@python.org>
References: <h4knsn$u76$1@lec.cs.unibo.it>
	<mailman.3811.1248747906.8015.python-list@python.org>
Message-ID: <h4marm$4j5$1@lec.cs.unibo.it>

Gabriel Genellina wrote:
> En Mon, 27 Jul 2009 16:35:51 -0300, jacopo mondi <mondi at cs.unibo.it>
> escribi?:
> 
>> Is there a reason why there is no ioctl interface for socket either then
>> for windows platform? It's technical issues or what else??
> 
> I don't completely understand your question. On Windows, you can use
> socket.ioctl with sockets, and DeviceIoControl (from the pywin32 package)
> with other files. On Linux, you have fcntl.ioctl that works with any kind
> of file.
> 
Ok, thanks a lot, my question was because I didn't know about
fcntl.ioct, I thought that ioctl wrapping was implemented inside
socketmodule.c as 'bind', 'connect', 'accept' etc. are, and I was
disoriented because no documentation for socket usage on Linux nor the
code have references about ioctl, except for windows.

I hope the reason why you didn't completely understood my question is
not my english, if it be so I'm sorry and I ask anyone to correct me,
it's the only way to improve ;)

thanks a lot
	jacopo


From user at example.net  Tue Jul 28 06:07:46 2009
From: user at example.net (superpollo)
Date: Tue, 28 Jul 2009 12:07:46 +0200
Subject: Extract images from PDF files
In-Reply-To: <mailman.3815.1248752499.8015.python-list@python.org>
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
	<mailman.3815.1248752499.8015.python-list@python.org>
Message-ID: <4a6ecdf3$0$40015$4fafbaef@reader3.news.tin.it>

David Lyon wrote:
> pdftohtml on sourceforge may help...
> 

also see: http://linuxcommand.org/man_pages/pdfimages1.html

bye


From __peter__ at web.de  Tue Jul 28 06:14:34 2009
From: __peter__ at web.de (Peter Otten)
Date: Tue, 28 Jul 2009 12:14:34 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>
Message-ID: <h4mj25$6g5$00$2@news.t-online.com>

NiklasRTZ wrote:

> On Jul 28, 5:02 am, Bearophile <bearophileH... at lycos.com> wrote:
>> On Jul 28, 10:26 am, NiklasRTZ <nikla... at gmail.com> wrote:
>>
>> > Newbie hello onwards to the .py manual asks meantime how the longest
>> > word gets determined?
>> > First word, ok
>> > 'a aa aaa aa'[:'a aa aaa aa'.find(' ',1,10)]
>>
>> Your language is not easy to understand, but I think you want to find
>> the longest word in a string.
>> If this is the input string:
>> txt = "a aa aaa aa"
>>
>> There are several ways to do it, I'll show a simple one.
>>
>> You can split it into its parts (not having Python a built-in lazy
>> split yet, you can split it all at once). You can do it with the
>> string split method. It produces a list of the words, more or less
>> (but you may have words like "gone,", you may have to take care of
>> them too, this requires some code.
>>
>> Once you have a list of words, you have to take the longest. A simple
>> way is to replace each word with a tuple that contains the length of
>> the word and the word itself, then pick the tuple with the highest
>> length value. But Python allows you to do such operation in a faster
>> way: you can use the max() function, it has a "key" function that
>> allows you to remap on the fly what you mean by "max". So you just
>> have to give it a function (reference) that given the word spits its
>> length, such function is "len" itself.
>>
>> If you instead want to find the position of the longest word the
>> program gets a little longer. Ask if you need something different.
>>
>> Bye,
>> bearophile
> 
> Thank you. This seems to work:
> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
> len(b))[-1]
> 'sdfsdfsdfsdf'

To spell out bearophile's more efficient suggestion:

>>> max("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(), key=len)
'sdfsdfsdfsdf'





From niklasro at gmail.com  Tue Jul 28 06:23:58 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 03:23:58 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com> 
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com> 
	<h4mj16$6g5$00$1@news.t-online.com>
Message-ID: <8a6313a3-5575-4195-a318-b823af0682fc@e11g2000yqo.googlegroups.com>

There were 3 solutions. Everybody's homework is someone's "what's
this?"
max('asdasfd faop29v8 asejrhjhw  awg5w35g   aw3g5aw3g
kajhsdkfhlskjdhfakljsdhf awg3   aw3'.split(), key=len)
sorted("a AAA aa aaaaa sdfsdfsdfsdf vv".split(' '),key=len)[-1]
sorted("a AAA aa aaaaa vv".split(' '),lambda a,b: len(a)-len(b))[-1]


From jakecjacobson at gmail.com  Tue Jul 28 06:35:55 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Tue, 28 Jul 2009 03:35:55 -0700 (PDT)
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<slrnh6t7lt.o4a.nick@irishsea.home.craig-wood.com>
Message-ID: <c2d97820-1168-4a1d-9abc-958f073d607f@o15g2000yqm.googlegroups.com>

On Jul 28, 3:29?am, Nick Craig-Wood <n... at craig-wood.com> wrote:
> jakecjacobson <jakecjacob... at gmail.com> wrote:
> > ?I am getting the following error when doing a post to REST API,
>
> > ?Enter PEM pass phrase:
> > ?Traceback (most recent call last):
> > ? ?File "./ices_catalog_feeder.py", line 193, in ?
> > ? ? ?main(sys.argv[1])
> > ? ?File "./ices_catalog_feeder.py", line 60, in main
> > ? ? ?post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
> > ?(input_dir, file), collection_name, key_file, cert_file)
> > ? ?File "./ices_catalog_feeder.py", line 125, in post2Catalog
> > ? ? ?connection.request('POST', path, parameters, head)
> > ? ?File "/usr/lib/python2.4/httplib.py", line 810, in request
> > ? ? ?self._send_request(method, url, body, headers)
> > ? ?File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
> > ? ? ?self.endheaders()
> > ? ?File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
> > ? ? ?self._send_output()
> > ? ?File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
> > ? ? ?self.send(msg)
> > ? ?File "/usr/lib/python2.4/httplib.py", line 652, in send
> > ? ? ?self.connect()
> > ? ?File "/usr/lib/python2.4/httplib.py", line 1079, in connect
> > ? ? ?ssl = socket.ssl(sock, self.key_file, self.cert_file)
> > ? ?File "/usr/lib/python2.4/socket.py", line 74, in ssl
> > ? ? ?return _realssl(sock, keyfile, certfile)
> > ?socket.sslerror: (1, 'error:14094412:SSL
> > ?routines:SSL3_READ_BYTES:sslv3 alert bad certificate')
>
> > ?My code where this error occurs is:
>
> > ?head = {"Content-Type" : "application/x-www-form-urlencoded",
> > ?"Accept" : "text/plain"}
> > ?parameters = urlencode({"collection" : collection, "entryxml" : open
> > ?(file,'r').read()})
> > ?print "Sending the file to: " + host
>
> > ?try:
> > ? ?try:
> > ? ? ? ? ? ?# Default port is 443.
> > ? ? ? ? ? ?# key_file is the name of a PEM formatted file that contains your
> > ?private key.
> > ? ? ? ? ? ?# cert_file is a PEM formatted certificate chain file.
> > ? ? ? ? ? ?connection = httplib.HTTPSConnection(host, int(port), key_file,
> > ?cert_file)
> > ? ? ? ? ? ?connection.request('POST', path, parameters, head)
> > ? ? ? ? ? ?response = connection.getresponse()
> > ? ? ? ? ? ?print response.status, response.reason
> > ? ?except httplib.error, (value,message):
> > ? ? ? ? ? ?print value + ':' + message
> > ?finally:
> > ? ?connection.close()
>
> > ?I was wondering if this is due to the server having a invalid server
> > ?cert?
>
> I'd say judging from the traceback you messed up key_file or cert_file
> somehow.
>
> Try using the openssl binary on them (read the man page to see how!)
> to check them out.
>
> > ?If I go to this server in my browser, I get a "This server tried to
> > ?identify itself with invalid information". ?Is there a way to
> > ?ignore this issue with Python? ?Can I setup a trust store and add
> > ?this server to the trust store?
>
> Invalid how? ?Self signed certificate? Domain mismatch? Expired certificate?
>
> --
> Nick Craig-Wood <n... at craig-wood.com> --http://www.craig-wood.com/nick

Nick,

Thanks for the help on this.  I will check my steps on openssl again
and see if I messed up.  What I tried to do was:
1.  Save my PKI cert to disk.  It was saved as a P12 file
2.  Use openssl to convert it to the needed .pem file type
3.  Saved the CA that my cert was signed by as a .crt file

These are the 2 files that I was using for key_file and
 * cert_file -> CA
 * key_file -> my PKI cert converted to a .pem file

"Invalid how?  Self signed certificate? Domain mismatch? Expired
certificate?"  It is a server name mismatch.

For everyone that wants to discuss why we shouldn't do this, great but
I can't change the fact that I need to do this.  I can't use http or
even get a correct cert at this time.  This is a quick a dirty project
to demonstrate capability.  I need something more than slide show
briefs.


From davea at ieee.org  Tue Jul 28 06:43:16 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 28 Jul 2009 06:43:16 -0400
Subject: where do I put resources (images, audio files) when I wrote
	Python program?
In-Reply-To: <op.uxq8a1g6x6zn5v@lepton.softlabbsas.com.ar>
References: <h4ksgo$qa9$1@inews.gazeta.pl> <4A6E13B8.4080806@ieee.org>
	<op.uxq8a1g6x6zn5v@lepton.softlabbsas.com.ar>
Message-ID: <4A6ED644.7000805@ieee.org>

Gabriel Genellina wrote:
> For those read-only resources I'd use pkgutil.get_data (instead of
> manually parsing __file__):
>
> http://docs.python.org/library/pkgutil.html#pkgutil.get_data
>
> It's easier to manage when someone later decide to install the package as
> an egg file, or distribute it using py2exe. Quoting the documentation:
>
> """The function returns a binary string that is the contents of the
> specified resource.
>
> For packages located in the filesystem, which have already been imported,
> this is the rough equivalent of:
>
> d = os.path.dirname(sys.modules[package].__file__)
> data = open(os.path.join(d, resource), 'rb').read()
> return data
> """
>
Thanks Gabriel, I hadn't come across get_data() yet.

DaveA


From gagsl-py2 at yahoo.com.ar  Tue Jul 28 06:56:27 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Tue, 28 Jul 2009 07:56:27 -0300
Subject: ioctl on socket
References: <h4knsn$u76$1@lec.cs.unibo.it>
	<mailman.3811.1248747906.8015.python-list@python.org>
	<h4marm$4j5$1@lec.cs.unibo.it>
Message-ID: <op.uxrx0dhtx6zn5v@gabriel.sleipnir-bsas>

En Tue, 28 Jul 2009 07:05:43 -0300, jacopo mondi <mondi at cs.unibo.it>  
escribi?:
> Gabriel Genellina wrote:
>> En Mon, 27 Jul 2009 16:35:51 -0300, jacopo mondi <mondi at cs.unibo.it>
>> escribi?:
>>
>>> Is there a reason why there is no ioctl interface for socket either  
>>> then
>>> for windows platform? It's technical issues or what else??
>>
>> I don't completely understand your question. On Windows, you can use
>> socket.ioctl with sockets, and DeviceIoControl (from the pywin32  
>> package)
>> with other files. On Linux, you have fcntl.ioctl that works with any  
>> kind
>> of file.
>>
> Ok, thanks a lot, my question was because I didn't know about
> fcntl.ioct, I thought that ioctl wrapping was implemented inside
> socketmodule.c as 'bind', 'connect', 'accept' etc. are, and I was
> disoriented because no documentation for socket usage on Linux nor the
> code have references about ioctl, except for windows.

I see; socket.ioctl should menction fcntl.ioctl; I'll submit a  
documentation patch.

-- 
Gabriel Genellina



From hniksic at xemacs.org  Tue Jul 28 07:03:54 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 28 Jul 2009 13:03:54 +0200
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com>
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com>
	<m2my6p9mj5.fsf@cs.uu.nl>
Message-ID: <87prblul0l.fsf@busola.homelinux.net>

Piet van Oostrum <piet at cs.uu.nl> writes:

>>>>>> NiklasRTZ <niklasro at gmail.com> (N) wrote:
>
>>N> Thank you. This seems to work:
>>N> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
>>N> len(b))[-1]
>>N> 'sdfsdfsdfsdf'
>
> simpler:
>
> sorted("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '), key=len)[-1]

There is no need to sort the sequence to obtain the largest element.
The max function is designed to do exactly that, and also supports the
key argument:

>>> max("a AAA aa aaaaa  sdfsdfsdfsdf vv".split(' '), key=len)
'sdfsdfsdfsdf'


From Ray.Joseph at CDICorp.com  Tue Jul 28 07:54:00 2009
From: Ray.Joseph at CDICorp.com (ray)
Date: Tue, 28 Jul 2009 04:54:00 -0700 (PDT)
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org> 
	<m21vo2czeb.fsf@cs.uu.nl> <468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com> 
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com> 
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com> 
	<mailman.3784.1248709156.8015.python-list@python.org>
Message-ID: <b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>

On Jul 27, 10:39?am, David Cournapeau <courn... at gmail.com> wrote:
> On Tue, Jul 28, 2009 at 12:28 AM, Dotan Cohen<dotanco... at gmail.com> wrote:
> >> It is neither efficient or inefficient: it is just a distribution
> >> tool, to deploy python software in a form familiar to most windows
> >> users. It does not make it any faster than running the software under
> >> a python prompt.
>
> >> As much as I like python for scientific programming, I would say
> >> python is pretty far from the stated requirements in the posted blog
> >> post. It is difficult to deploy software written with python (much
> >> better than the alternatives, though), and it is slow if you can't
> >> leverage numpy/scipy (where vectorization does not apply).
>
> >> It remains to be seen whether it will be true in practice, but
> >> something like F#, with its integration in VS 2010, seems much closer
> >> IMHO. It is compiled, high level language, and backed by the biggest
> >> software vendor in the world.
>
> > The blog post is not looking to distribute his code, but he would like
> > it to be cross platform for his own reasons. VB is not cross platform.
>
> I understand his "efficient binary as Ansi C" partially as a
> deployment requirement, and independent of cross-platform issues. As a
> scientist, being able to share my software with colleagues is a non
> trivial matter. Python does not make this easy today.
>
> F# has nothing to do with VB: F# is a ML-language inspired from OCAML,
> and run on top of the CLR. It can thus leverage the huge .net
> framework (lack of non numerical API is one of the biggest matlab
> hindrance, and comparatively big advantage of python + numpy/scipy),
> and benefits from the much more efficient implementation compared to
> python (under the currently CPython implementation at least).
>
> Some recent F# versions are compatible with mono, making it compatible
> on most platforms that matter today for research (but of course, you
> lose the IDE integration outside windows).
>
> David- Hide quoted text -
>
> - Show quoted text -
I wish . . .

For comparisons, Mathcad has the symbolic notation appropriate for
mathematical communications.  I like features of Mathematica and Maple
but Mathcad provides for the user to 'stay' with mathematical
symbolism longer.  I prefer Matlab execution environment.  So I
develop concepts in Mathcad, prove them in Matlab and then compile to
through C where direct performance is required.  Maple and Matlab have
this type of relation.

Matlab, from The Mathworks, has a companion product called Simulink.
This allows the user to graphically build ?algorithms? in block form.
There is a similar Python function.

Each of these components would best be served if allowed to exist
independently but supported with transparent integration.  I would
like to develop in a stable user environment - a stable GUI.  And then
allow efficient algorithms behind the scenes.

By separating the functionality of the workspace, the user can be
given (or create at will) a GUI that suites her desires and provides
for the creativity and productivity she chooses.  The functionality
under the GUI should then be pluggable.  Developers can provide
solutions from many directions, compete for varying performance
requirements, enhance functional features technology changes, and
still not disturb the fragile user interface.

Allow the user the comfort of home.  Let them keep whatever GUI suits
them and provide for their deployment (if any) needs behind the
scenes.

Ray






From niklasro at gmail.com  Tue Jul 28 07:55:26 2009
From: niklasro at gmail.com (NiklasRTZ)
Date: Tue, 28 Jul 2009 04:55:26 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com> 
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com> 
	<m2my6p9mj5.fsf@cs.uu.nl> <87prblul0l.fsf@busola.homelinux.net>
Message-ID: <c8ff2ba2-b62b-40e8-ae7e-b78cac491812@s31g2000yqs.googlegroups.com>

On Jul 28, 7:03?am, Hrvoje Niksic <hnik... at xemacs.org> wrote:
> Piet van Oostrum <p... at cs.uu.nl> writes:
>
> >>>>>> NiklasRTZ <nikla... at gmail.com> (N) wrote:
>
> >>N> Thank you. This seems to work:
> >>N> sorted("a AAA aa aaaaa ?sdfsdfsdfsdf vv".split(' '),lambda a,b: len(a)-
> >>N> len(b))[-1]
> >>N> 'sdfsdfsdfsdf'
>
> > simpler:
>
> > sorted("a AAA aa aaaaa ?sdfsdfsdfsdf vv".split(' '), key=len)[-1]
>
> There is no need to sort the sequence to obtain the largest element.
> The max function is designed to do exactly that, and also supports the
> key argument:
>
> >>> max("a AAA aa aaaaa ?sdfsdfsdfsdf vv".split(' '), key=len)
>
> 'sdfsdfsdfsdf'

Sincere thanks for strengthening python's superior flexibility. Same
function also works around an exploding index problem returning
results for longest word where otherwise a word with whitespace
crashes the index:
all().search(max(q.split(), key=len)).filter("modified >",
timeline).filter("published =", True).filter("modified <=",
bookmark ).order("-modified").fetch(PAGESIZE+1)
Line below crashes the index for words with whitespace (unknown
researchable, only occurs live, works with development)
all().search(q).filter("modified >", timeline).filter("published =",
True).filter("modified <=", bookmark ).order("-modified").fetch
(PAGESIZE+1)
best regards,
Niklas


From tommy.nordgren at comhem.se  Tue Jul 28 07:58:32 2009
From: tommy.nordgren at comhem.se (Tommy Nordgren)
Date: Tue, 28 Jul 2009 13:58:32 +0200
Subject: I am trying to compile python 2.6.2 on my Mac
In-Reply-To: <50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
References: <ebe643f4-94ef-4ecd-86c1-e774244fd008@k13g2000prh.googlegroups.com>
	<50697b2c0907260137m16aff26djd91bd598eea10913@mail.gmail.com>
Message-ID: <E982B034-D069-4878-BAE6-51F467E7407B@comhem.se>


On Jul 26, 2009, at 10:37 AM, Chris Rebert wrote:

> On Sun, Jul 26, 2009 at 1:12 AM, Jessica R
> Smith<jessica.1980.smith at gmail.com> wrote:
>> Hello,
>> I am trying to compile Python 2.6.2 on my Mac which has os/x 10.5.7
>>
>> I downloaded python 2.6.2 from here:
>>  - http://www.python.org/ftp/python/2.6.2/Python-2.6.2.tar.bz2
>>
>> I unpacked it.
>>
>> I ran these shell commands:
>>  - ./configure --prefix=/pt/p
>>  - make
>>
>> Near the end of the make output I see this message:
>>
>> . Failed to find the necessary bits to build these modules:
>> . _bsddb             gdbm               linuxaudiodev
>> . ossaudiodev        readline           spwd
>> . sunaudiodev
>> . To find the necessary bits, look in setup.py in detect_modules()  
>> for
>> the module's name.
>>
>> I looked in setup.py in detect_modules()
>>
>> It is not clear to me how to proceed.
>>
>> I think that I want the module: "readline"
>>
>> I doubt I need the other modules like linuxaudiodev, etc.
>>
>> If you have any clues or opinions on how I can build the module
>> "readline",
>> please feel free to share.
>
> You need to install the GNU Readline library
> (http://tiswww.case.edu/php/chet/readline/rltop.html), which the
> module depends on.
>
	A better solution would be to configure the modules in question to use
the libreadline.dylib library already installed on every Mac OS X  
computer.
> You might consider installing Python through MacPorts or Fink instead,
> as they automate the compilation and installation process and take
> care of dependencies (such as GNU Readline) for you:
> http://www.macports.org/
> http://www.finkproject.org/
>
> Cheers,
> Chris
> -- 
> http://blog.rebertia.com
> -- 
> http://mail.python.org/mailman/listinfo/python-list

-----------------------------------
See the amazing new SF reel: Invasion of the man eating cucumbers from  
outer space.
On congratulations for a fantastic parody, the producer replies :  
"What parody?"

Tommy Nordgren
tommy.nordgren at comhem.se






From steve at REMOVE-THIS-cybersource.com.au  Tue Jul 28 08:02:40 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 28 Jul 2009 12:02:40 GMT
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3812.1248748204.8015.python-list@python.org>
Message-ID: <027ed9be$0$5185$c3e8da3@news.astraweb.com>

On Mon, 27 Jul 2009 23:16:39 -0300, Gabriel Genellina wrote:

> I don't see the point on "fixing" either the Python script or httplib to
> accomodate for an invalid server certificate... If it's just for
> internal testing, I'd use HTTP instead (at least until the certificate
> is fixed).

In real life, sometimes you need to drive with bad brakes on your car, 
walk down dark alleys in the bad part of town, climb a tree without a 
safety line, and use a hammer without wearing goggles. We can do all 
these things.

The OP has said that, for whatever reason, he needs to ignore a bad 
server certificate when connecting to HTTPS. Python is a language where 
developers are allowed to shoot themselves in the foot, so long as they 
do so in full knowledge of what they're doing.

So, putting aside all the millions of reasons why the OP shouldn't accept 
an invalid certificate, how can he accept an invalid certificate?



-- 
Steven


From nick at craig-wood.com  Tue Jul 28 08:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Tue, 28 Jul 2009 07:29:56 -0500
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<slrnh6t7lt.o4a.nick@irishsea.home.craig-wood.com>
	<c2d97820-1168-4a1d-9abc-958f073d607f@o15g2000yqm.googlegroups.com>
Message-ID: <slrnh6tpga.rn2.nick@irishsea.home.craig-wood.com>

jakecjacobson <jakecjacobson at gmail.com> wrote:
> > > ?If I go to this server in my browser, I get a "This server tried to
> > > ?identify itself with invalid information". ?Is there a way to
> > > ?ignore this issue with Python? ?Can I setup a trust store and add
> > > ?this server to the trust store?
> >
> > Invalid how? ?Self signed certificate? Domain mismatch? Expired
> > certificate?
>
>  For everyone that wants to discuss why we shouldn't do this, great but
>  I can't change the fact that I need to do this.  I can't use http or
>  even get a correct cert at this time.  This is a quick a dirty project
>  to demonstrate capability.  I need something more than slide show
>  briefs.

I wasn't making a value judgement - I was trying to help!  If you can
get a bit more information out of the browser as to why the
certificate is invalid it may help your python code.

Real certificates cost real money.  Usually a correctly set up
self-signed certificate is fine for dev stuff.  I'm certainly too
cheap to by real certificates for dev or internal stuff!

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From magobin at gmail.com  Tue Jul 28 08:50:35 2009
From: magobin at gmail.com (Alex)
Date: Tue, 28 Jul 2009 05:50:35 -0700 (PDT)
Subject: index nested lists
Message-ID: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>

hi at all,
 If I have this list:

>>> lista
['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]

if I want enumerate elements...I can see:

>>> for parola in lista:
	print lista[i]
	i = i + 1

ciao
1
['mela', 'pera', 'banana']
[1, 2, 3]
>>>

but, if I want to enumerate elements about nested lists ??, something
like:

ciao
1
mela
pera
banana
1
2
3

...How can I do ??

Alex


From dudekksoft at gmail.com  Tue Jul 28 08:54:26 2009
From: dudekksoft at gmail.com (redhot)
Date: Tue, 28 Jul 2009 05:54:26 -0700 (PDT)
Subject: File and TagPy
Message-ID: <11a3ce55-6ba5-4438-9b05-490686e258e6@k1g2000yqf.googlegroups.com>

Hello,
I have question, is it possible to read tag in tagpy module from file
stream?
For example I have earlier read file:
file = open('some.mp3', 'rb')

and next get tags from it?

Regards,
Konrad


From bakes at ymail.com  Tue Jul 28 08:59:02 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 05:59:02 -0700 (PDT)
Subject: FTP Offset larger than file.
Message-ID: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>

I am writing a python script that performs an identical function to
the 'tail' unix utility, except that it connects to its files over
FTP, rather than the local hard disk.

I am currently using this python script to generate an increasing
'logfile' of garbage.

> import time
> for i in range(1, 20000):
>	time.sleep(0.2)
>	print i
>	f = open("data1.log","a")
>	f.write('%s: This logfile is being automatically generated to help Bakes test his python ftptail. \n' % i)
>	f.close()

and use this script to actually download it.

>import time
>import os.path
>from ftplib import FTP
>
>#Empty the file
>filename = 'data1.log'
>file = open(filename, 'w')
>file.write('')
>file.close()
>
>def handleDownload(block):
>    file.write(block)
>    print ".",
>
># Create an instance of the FTP object
># Optionally, you could specify username and password:
>ftp=FTP(host, user, pass)
>
>directory = '/temp'
>ftp.cwd(directory)
>
>file = open(filename, 'a')
>
>for i in range(1,20000):
>  size=os.path.getsize('data1.log')
>  ftp.retrbinary('RETR ' + filename, handleDownload, rest=size)
>
>file.close()
>
>print ftp.close()

Now, my problem is that I get a very strange error. What should be
happening is the script gets the size of the local file before
downloading all of the external file after that offset.

The error I get is:
ftplib.error_temp: 451-Restart offset 24576 is too large for file size
22852.
451 Restart offset reset to 0
which tells me that the local file is larger than the external file,
by about a kilobyte. Certainly, the local file is indeed that size, so
my local script is doing the right things. I do wonder what is going
wrong, can anyone enlighten me?


From npuloski at gmail.com  Tue Jul 28 09:09:18 2009
From: npuloski at gmail.com (Nanime Puloski)
Date: Tue, 28 Jul 2009 09:09:18 -0400
Subject: Internal Math Library of Numpy
Message-ID: <d785f9cc0907280609w2e8d7cddgbf8b3850518e28bc@mail.gmail.com>

Does Numpy use Python's standard math library when calculating
elementary functions such as exp(x) and acos(x)? Also, what is the
internal library of Numpy and Python's standard math library? Is it
platform independent?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/13797243/attachment-0001.html>

From andreas.tawn at ubisoft.com  Tue Jul 28 09:12:41 2009
From: andreas.tawn at ubisoft.com (Andreas Tawn)
Date: Tue, 28 Jul 2009 15:12:41 +0200
Subject: index nested lists
In-Reply-To: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>
References: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>
Message-ID: <8AEDA5E3386EA742B8C24C95FF0C758007B66A65@PDC-MAIL3.ubisoft.org>

> hi at all,
>  If I have this list:
> 
> >>> lista
> ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
> 
> if I want enumerate elements...I can see:
> 
> >>> for parola in lista:
> 	print lista[i]
> 	i = i + 1
> 
> ciao
> 1
> ['mela', 'pera', 'banana']
> [1, 2, 3]
> >>>
> 
> but, if I want to enumerate elements about nested lists ??, something
> like:
> 
> ciao
> 1
> mela
> pera
> banana
> 1
> 2
> 3
> 
> ...How can I do ??
> 
> Alex
> --
> http://mail.python.org/mailman/listinfo/python-list

You could do something like this.

def printNestedList(lst):
    if isinstance(lst, list):
        for element in lst:
            printNestedList(element)
    else:
        print lst

myList = ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
printNestedList(myList)

>>>
ciao
1
mela
pera
banana
1
2
3

Cheers, Drea


From magobin at gmail.com  Tue Jul 28 09:19:03 2009
From: magobin at gmail.com (Alex)
Date: Tue, 28 Jul 2009 06:19:03 -0700 (PDT)
Subject: index nested lists
References: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>
	<mailman.3833.1248786776.8015.python-list@python.org>
Message-ID: <ce51e8e6-bfc7-4b1c-a171-59468eb6ce9b@g31g2000yqc.googlegroups.com>

On 28 Lug, 15:12, "Andreas Tawn" <andreas.t... at ubisoft.com> wrote:
> > hi at all,
> > ?If I have this list:
>
> > >>> lista
> > ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
>
> > if I want enumerate elements...I can see:
>
> > >>> for parola in lista:
> > ? ?print lista[i]
> > ? ?i = i + 1
>
> > ciao
> > 1
> > ['mela', 'pera', 'banana']
> > [1, 2, 3]
>
> > but, if I want to enumerate elements about nested lists ??, something
> > like:
>
> > ciao
> > 1
> > mela
> > pera
> > banana
> > 1
> > 2
> > 3
>
> > ...How can I do ??
>
> > Alex
> > --
> >http://mail.python.org/mailman/listinfo/python-list
>
> You could do something like this.
>
> def printNestedList(lst):
> ? ? if isinstance(lst, list):
> ? ? ? ? for element in lst:
> ? ? ? ? ? ? printNestedList(element)
> ? ? else:
> ? ? ? ? print lst
>
> myList = ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
> printNestedList(myList)
>


thanks a lot !

Alex


From michele.petrazzo at REMOVE_me_unipex.it  Tue Jul 28 09:30:49 2009
From: michele.petrazzo at REMOVE_me_unipex.it (Michele Petrazzo)
Date: Tue, 28 Jul 2009 15:30:49 +0200
Subject: python 3 and stringio.seek
Message-ID: <h4mui9$q1o$1@nnrp-beta.newsland.it>

Hi list,
I'm trying to port a my library to python 3, but I have a problem with a
the stringio.seek:
the method not accept anymore a value like pos=-6 mode=1, but the "old"
(2.X) version yes...

The error:
   File "/home/devel/Py3/lib/python3.0/io.py", line 2031, in seek
     return self._seek(pos, whence)
IOError: Can't do nonzero cur-relative seeks


How solve this?

Thanks,
MIchele


From nobody at nowhere.com  Tue Jul 28 09:31:56 2009
From: nobody at nowhere.com (Nobody)
Date: Tue, 28 Jul 2009 14:31:56 +0100
Subject: Gracefully exiting CLI application
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
Message-ID: <pan.2009.07.28.13.31.56.265000@nowhere.com>

On Mon, 27 Jul 2009 22:35:01 +0200, David wrote:

> I am writing a command line application, and I need to perform some
> cleaning on exit even if the process is killed. How can I do that with
> python?

Killed by what means?

Ctrl-C sends SIGINT which is converted to a KeyboardInterrupt exception.
This can be caught, or if it's allowed to terminate the process, any exit
handlers registered via atexit.register() will be used.

For other signals, you can install a handler with signal.signal(). This
can call sys.exit() or raise an exception (e.g. KeyboardInterrupt).

OTOH, if the process is terminated by SIGKILL, there's nothing you can do
about it. And although it's possible to trap SIGSEGV, you shouldn't assume
that the Python interpreter is still functional at this point.



From jeanmichel at sequans.com  Tue Jul 28 09:39:56 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Tue, 28 Jul 2009 15:39:56 +0200
Subject: index nested lists
In-Reply-To: <ce51e8e6-bfc7-4b1c-a171-59468eb6ce9b@g31g2000yqc.googlegroups.com>
References: <c46eb129-2b8e-4537-8ce4-2e191500040d@d4g2000yqa.googlegroups.com>	<mailman.3833.1248786776.8015.python-list@python.org>
	<ce51e8e6-bfc7-4b1c-a171-59468eb6ce9b@g31g2000yqc.googlegroups.com>
Message-ID: <4A6EFFAC.30106@sequans.com>

Alex wrote:
> On 28 Lug, 15:12, "Andreas Tawn" <andreas.t... at ubisoft.com> wrote:
>   
>>> hi at all,
>>>  If I have this list:
>>>       
>>>>>> lista
>>>>>>             
>>> ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
>>>       
>>> if I want enumerate elements...I can see:
>>>       
>>>>>> for parola in lista:
>>>>>>             
>>>    print lista[i]
>>>    i = i + 1
>>>       
>>> ciao
>>> 1
>>> ['mela', 'pera', 'banana']
>>> [1, 2, 3]
>>>       
>>> but, if I want to enumerate elements about nested lists ??, something
>>> like:
>>>       
>>> ciao
>>> 1
>>> mela
>>> pera
>>> banana
>>> 1
>>> 2
>>> 3
>>>       
>>> ...How can I do ??
>>>       
>>> Alex
>>> --
>>> http://mail.python.org/mailman/listinfo/python-list
>>>       
>> You could do something like this.
>>
>> def printNestedList(lst):
>>     if isinstance(lst, list):
>>         for element in lst:
>>             printNestedList(element)
>>     else:
>>         print lst
>>
>> myList = ['ciao', 1, ['mela', 'pera', 'banana'], [1, 2, 3]]
>> printNestedList(myList)
>>
>>     
>
>
> thanks a lot !
>
> Alex
>   
One hidden suggestion in Andreas answer is to write your code in 
english, if you can :o)

JM


From exarkun at divmod.com  Tue Jul 28 09:48:02 2009
From: exarkun at divmod.com (Jean-Paul Calderone)
Date: Tue, 28 Jul 2009 09:48:02 -0400
Subject: bad certificate error
In-Reply-To: <c2d97820-1168-4a1d-9abc-958f073d607f@o15g2000yqm.googlegroups.com>
Message-ID: <20090728134802.11822.1316828413.divmod.quotient.0@henry.divmod.com>

On Tue, 28 Jul 2009 03:35:55 -0700 (PDT), jakecjacobson <jakecjacobson at gmail.com> wrote:
> [snip]
>
>"Invalid how?  Self signed certificate? Domain mismatch? Expired
>certificate?"  It is a server name mismatch.

Python 2.4 is not capable of allowing you to customize this verification
behavior.  It is hard coded to let OpenSSL make the decision about whether
to accept the certificate or not.

Either M2Crypto or pyOpenSSL will let you ignore verification errors.  The
new ssl module in Python 2.6 may also as well.

Jean-Paul


From jakecjacobson at gmail.com  Tue Jul 28 09:52:37 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Tue, 28 Jul 2009 06:52:37 -0700 (PDT)
Subject: bad certificate error
References: <mailman.3835.1248788885.8015.python-list@python.org>
Message-ID: <332a5bba-48d5-4c8b-9c1e-288790d85dbb@o32g2000yqm.googlegroups.com>

On Jul 28, 9:48?am, Jean-Paul Calderone <exar... at divmod.com> wrote:
> On Tue, 28 Jul 2009 03:35:55 -0700 (PDT), jakecjacobson <jakecjacob... at gmail.com> wrote:
> > [snip]
>
> >"Invalid how? ?Self signed certificate? Domain mismatch? Expired
> >certificate?" ?It is a server name mismatch.
>
> Python 2.4 is not capable of allowing you to customize this verification
> behavior. ?It is hard coded to let OpenSSL make the decision about whether
> to accept the certificate or not.
>
> Either M2Crypto or pyOpenSSL will let you ignore verification errors. ?The
> new ssl module in Python 2.6 may also as well.
>
> Jean-Paul

Thanks, I will look into these suggestions.


From li.weidong at gmail.com  Tue Jul 28 09:54:21 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 06:54:21 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
Message-ID: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>

I am trying to build python 2.6.2 from the source by following the
instructions in README that comes with the source.  The configure and
make steps are fine, but there is an error in "make install" step.
This "make install" attempts to build a lot of lib, and it complains
about the lack of "unicodedata" shared object,

I looked at the source tree and the build result, unicodedata.so does
not exist.  I further notice that in Modules/Setup.dist, the line for
unicodedata.c is commented out by default.  So I uncomment it, and
experiment with rebuilding everything.

This time, with or without re-configure, the "make" step failed with a
link-time error when linking for libpython2.6.a due to "undefined
reference to 'initunicodedata'.  This symbol is defined in
unicodedata.c, but unicodedata.o is not used in linking for
libpython2.6.a, hence the error.  So this is a problem in the
generated Makefile.

Does anyone know what special things I have to do to avoid such
error?  Is there any known problems in the configure/make files in the
python 2.6.2 source code that require special patch?

Is unicodedata.c really needed in python 2.6.2?  If it is needed, why
it is commented out by default in Modules/Setup.dist?  If it is not
needed, why "make install" attempts to use it in compiling the
libraries?  Why those libraries are not designed to be compiled in the
make step, but in the install step?

Thanks for your help!

- Weidong




From li.weidong at gmail.com  Tue Jul 28 09:56:15 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 06:56:15 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
Message-ID: <01581b5a-3ddc-4ed8-abf4-ad41a542812c@l35g2000vba.googlegroups.com>

On Jul 28, 9:54?am, Weidong <li.weid... at gmail.com> wrote:
> I am trying to build python 2.6.2 from the source by following the
> instructions in README that comes with the source. ?The configure and
> make steps are fine, but there is an error in "make install" step.
> This "make install" attempts to build a lot of lib, and it complains
> about the lack of "unicodedata" shared object,
>
> I looked at the source tree and the build result, unicodedata.so does
> not exist. ?I further notice that in Modules/Setup.dist, the line for
> unicodedata.c is commented out by default. ?So I uncomment it, and
> experiment with rebuilding everything.
>
> This time, with or without re-configure, the "make" step failed with a
> link-time error when linking for libpython2.6.a due to "undefined
> reference to 'initunicodedata'. ?This symbol is defined in
> unicodedata.c, but unicodedata.o is not used in linking for
> libpython2.6.a, hence the error. ?So this is a problem in the
> generated Makefile.
>
> Does anyone know what special things I have to do to avoid such
> error? ?Is there any known problems in the configure/make files in the
> python 2.6.2 source code that require special patch?
>
> Is unicodedata.c really needed in python 2.6.2? ?If it is needed, why
> it is commented out by default in Modules/Setup.dist? ?If it is not
> needed, why "make install" attempts to use it in compiling the
> libraries? ?Why those libraries are not designed to be compiled in the
> make step, but in the install step?
>
> Thanks for your help!
>
> - Weidong

To add some info: This experiment was done on Linux, Ubuntu 8.x.


From hniksic at xemacs.org  Tue Jul 28 10:01:52 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 28 Jul 2009 16:01:52 +0200
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
Message-ID: <87ljm8vrcf.fsf@busola.homelinux.net>

Bakes <bakes at ymail.com> writes:

> The error I get is:
> ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> 22852.
> 451 Restart offset reset to 0
> which tells me that the local file is larger than the external file,
> by about a kilobyte. Certainly, the local file is indeed that size, so
> my local script is doing the right things. I do wonder what is going
> wrong, can anyone enlighten me?

I'd say you failed to take buffering into account.  You write into a
buffered file, yet you use os.path.getsize() to find out the current
file size.  If the data is not yet flushed, you keep re-reading the same
stuff from the remote file, and writing it out.  Once the buffer is
flushed, your file will contain more data than was retrieved from the
remote side, and eventually this will result in the error you see.

As a quick fix, you can add a file.flush() line after the
file.write(...) line, and the problem should go away.


From python-url at phaseit.net  Tue Jul 28 10:07:28 2009
From: python-url at phaseit.net (Gabriel Genellina)
Date: Tue, 28 Jul 2009 14:07:28 +0000 (UTC)
Subject: Python-URL! - weekly Python news and links (Jul 28)
Message-ID: <h4n0n0$7ob$1@lairds.us>

QOTW:  "But there's another principle at work here that's less well known, and
that was first articulated to me by Robert Dewar: You can remove linear
factors by profiling, but it's much harder to undo bad algorithmic decisions. 
In particular, whether a program runs in O(n) or O(n^2) sometimes depends on
decisions that have to be frozen fairly early in the design." - Andrew Koenig

    
    Comparing the performance of the same algorithm using many compilers:
    CPython, psyco, Cython, ShedSkin, Unladen Swallow, Java, C and D:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/8d793c46903cc0b6/
    
    MRAB has written a new implementation of re module with many new
    features, and he's looking for feedback:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/16c139b0a52ab023/
    
    Importing two modules with the same name from different directories:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3cb83a30e1b2c202/
    
    Cleanly exiting an application, even if it gets killed by a signal:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/d60b8e0d93aeaaf9/
    
    How can a child thread notify a parent thread of its status?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/d1d7f55716aacedc/
    
    How to attach a docstring to global constants/variables?
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/ac54186ad873036a/
    
    In Python -unlike other languages- it does not make sense to treat
    numbers (scalars) as vectors of length 1:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/3ef498c906bd7e2d/
    
    isinstance may take a tuple of types as its second argument: why a
    tuple, and not a list, or a set?
        http://mail.python.org/pipermail/python-list/2009-July/721205.html
    
    How to overcome the normal 2GB allocation limit of Windows XP, 32bits:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/59851df6e54f9ef0/
    
    Distinguishing active generators from exhausted ones:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/9ff179e8cb5e9bc/
    
    Peter Otten must be, undoubtedly, Sherlock Holmes reincarnated:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/838177c8a37d2b7c/
    
    And Piet van Oostrum is not much behind him:
        http://groups.google.com/group/comp.lang.python/browse_thread/thread/d1f8627413cd3c4e/
    
    
========================================================================
Everything Python-related you want is probably one or two clicks away in
these pages:

    Python.org's Python Language Website is the traditional
    center of Pythonia
        http://www.python.org
    Notice especially the master FAQ
        http://www.python.org/doc/FAQ.html

    PythonWare complements the digest you're reading with the
    marvelous daily python url
         http://www.pythonware.com/daily

    Just beginning with Python?  This page is a great place to start:
	http://wiki.python.org/moin/BeginnersGuide/Programmers

    The Python Papers aims to publish "the efforts of Python enthusiasts":
	http://pythonpapers.org/
    The Python Magazine is a technical monthly devoted to Python:
	http://pythonmagazine.com

    Readers have recommended the "Planet" sites:
	http://planetpython.org
	http://planet.python.org

    comp.lang.python.announce announces new Python software.  Be
    sure to scan this newsgroup weekly.
        http://groups.google.com/group/comp.lang.python.announce/topics

    Python411 indexes "podcasts ... to help people learn Python ..."
    Updates appear more-than-weekly:
        http://www.awaretek.com/python/index.html

    The Python Package Index catalogues packages.
        http://www.python.org/pypi/

    Much of Python's real work takes place on Special-Interest Group
    mailing lists
        http://www.python.org/sigs/

    Python Success Stories--from air-traffic control to on-line
    match-making--can inspire you or decision-makers to whom you're
    subject with a vision of what the language makes practical.
        http://www.pythonology.com/success

    The Python Software Foundation (PSF) has replaced the Python
    Consortium as an independent nexus of activity.  It has official
    responsibility for Python's development and maintenance.
        http://www.python.org/psf/
    Among the ways you can support PSF is with a donation.
        http://www.python.org/psf/donations/

    The Summary of Python Tracker Issues is an automatically generated
    report summarizing new bugs, closed ones, and patch submissions. 
        http://search.gmane.org/?author=status%40bugs.python.org&group=gmane.comp.python.devel&sort=date

    Although unmaintained since 2002, the Cetus collection of Python
    hyperlinks retains a few gems.
        http://www.cetus-links.org/oo_python.html

    Python FAQTS
        http://python.faqts.com/

    The Cookbook is a collaborative effort to capture useful and
    interesting recipes.
	http://code.activestate.com/recipes/langs/python/

    Many Python conferences around the world are in preparation.
    Watch this space for links to them.

    Among several Python-oriented RSS/RDF feeds available, see:
        http://www.python.org/channews.rdf
    For more, see:
        http://www.syndic8.com/feedlist.php?ShowMatch=python&ShowStatus=all
    The old Python "To-Do List" now lives principally in a
    SourceForge reincarnation.
        http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse
	http://www.python.org/dev/peps/pep-0042/

    del.icio.us presents an intriguing approach to reference commentary.
    It already aggregates quite a bit of Python intelligence.
        http://del.icio.us/tag/python

    Enjoy the *Python Magazine*.
	http://pymag.phparch.com/

    *Py: the Journal of the Python Language*
        http://www.pyzine.com

    Dr.Dobb's Portal is another source of Python news and articles:
        http://www.ddj.com/TechSearch/searchResults.jhtml?queryText=python
    and Python articles regularly appear at IBM DeveloperWorks:
        http://www.ibm.com/developerworks/search/searchResults.jsp?searchSite=dW&searchScope=dW&encodedQuery=python&rankprofile=8

Previous - (U)se the (R)esource, (L)uke! - messages are listed here:
  http://search.gmane.org/?query=python+URL+weekly+news+links&group=gmane.comp.python.general&sort=date
  http://groups.google.com/groups/search?q=Python-URL!+group%3Acomp.lang.python&start=0&scoring=d&
  http://lwn.net/Search/DoSearch?words=python-url&ctype3=yes&cat_25=yes

There is *not* an RSS for "Python-URL!"--at least not yet.  Arguments
for and against are occasionally entertained.


Suggestions/corrections for next week's posting are always welcome.
E-mail to <Python-URL at phaseit.net> should get through.

To receive a new issue of this posting in e-mail each Monday morning
(approximately), ask <claird at phaseit.net> to subscribe.  Mention
"Python-URL!".  Write to the same address to unsubscribe.


-- The Python-URL! Team--

Phaseit, Inc. (http://phaseit.net) is pleased to participate in and
sponsor the "Python-URL!" project.  Watch this space for upcoming
news about posting archives.


From lists at cheimes.de  Tue Jul 28 10:17:20 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 28 Jul 2009 16:17:20 +0200
Subject: Questions about unicodedata in python 2.6.2
In-Reply-To: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
Message-ID: <h4n19g$l3p$1@ger.gmane.org>

Weidong schrieb:
> I am trying to build python 2.6.2 from the source by following the
> instructions in README that comes with the source.  The configure and
> make steps are fine, but there is an error in "make install" step.
> This "make install" attempts to build a lot of lib, and it complains
> about the lack of "unicodedata" shared object,

unicodedata is usually build as a shared library and not linked into the
Python core. How did you configure Python? The usual prodecure is:

   ./configure
   make
   sudo make install

On Unix the preferred option for ./configure is "--enable-unicode=ucs4".

Christian



From gdamjan at gmail.com  Tue Jul 28 10:17:45 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Tue, 28 Jul 2009 16:17:45 +0200
Subject: If Scheme is so good why MIT drops it?
References: <mailman.3557.1248296000.8015.python-list@python.org>
	<64cf5074-485f-4e16-87a7-e7929dc346d8@v15g2000prn.googlegroups.com>
Message-ID: <9td3k6-eid.ln1@archaeopteryx.softver.org.mk>

> So do all these OSes have some kind of __mega_unifying_poll system
> call that works for anything that might possibly block, that you can
> exploit from a user process?

On Linux at least, the select/poll/epoll is that system, the trick is to 
use eventfd, timerfd and signalfd which are Linux specific system calls.

I think that covers everything needed. (eventfd is used for semaphores)


-- 
?????? ( http://softver.org.mk/damjan/ )

Give me the knowledge to change the code I do not accept, 
the wisdom not to accept the code I cannot change, 
and the freedom to choose my preference.



From bakes at ymail.com  Tue Jul 28 10:18:48 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 07:18:48 -0700 (PDT)
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
Message-ID: <bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>

On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
> Bakes <ba... at ymail.com> writes:
> > The error I get is:
> > ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> > 22852.
> > 451 Restart offset reset to 0
> > which tells me that the local file is larger than the external file,
> > by about a kilobyte. Certainly, the local file is indeed that size, so
> > my local script is doing the right things. I do wonder what is going
> > wrong, can anyone enlighten me?
>
> I'd say you failed to take buffering into account. ?You write into a
> buffered file, yet you use os.path.getsize() to find out the current
> file size. ?If the data is not yet flushed, you keep re-reading the same
> stuff from the remote file, and writing it out. ?Once the buffer is
> flushed, your file will contain more data than was retrieved from the
> remote side, and eventually this will result in the error you see.
>
> As a quick fix, you can add a file.flush() line after the
> file.write(...) line, and the problem should go away.

Thank you very much, that worked perfectly.


From bakes at ymail.com  Tue Jul 28 10:33:05 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 07:33:05 -0700 (PDT)
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
Message-ID: <fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>

On 28 July, 15:18, Bakes <ba... at ymail.com> wrote:
> On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
>
>
>
> > Bakes <ba... at ymail.com> writes:
> > > The error I get is:
> > > ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> > > 22852.
> > > 451 Restart offset reset to 0
> > > which tells me that the local file is larger than the external file,
> > > by about a kilobyte. Certainly, the local file is indeed that size, so
> > > my local script is doing the right things. I do wonder what is going
> > > wrong, can anyone enlighten me?
>
> > I'd say you failed to take buffering into account. ?You write into a
> > buffered file, yet you use os.path.getsize() to find out the current
> > file size. ?If the data is not yet flushed, you keep re-reading the same
> > stuff from the remote file, and writing it out. ?Once the buffer is
> > flushed, your file will contain more data than was retrieved from the
> > remote side, and eventually this will result in the error you see.
>
> > As a quick fix, you can add a file.flush() line after the
> > file.write(...) line, and the problem should go away.
>
> Thank you very much, that worked perfectly.

Actually, no it didn't. That fix works seamlessly in Linux, but gave
the same error in a Windows environment. Is that expected?


From stef.mientki at gmail.com  Tue Jul 28 10:35:39 2009
From: stef.mientki at gmail.com (Stef Mientki)
Date: Tue, 28 Jul 2009 16:35:39 +0200
Subject: Looking for a dream language: sounds like Python to me.
In-Reply-To: <b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>
References: <mailman.3743.1248636898.8015.python-list@python.org>
	<m21vo2czeb.fsf@cs.uu.nl>
	<468250.83203.qm@web31106.mail.mud.yahoo.com>	<4A6DC0FC.90704@stoneleaf.us>	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com>
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com>
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com>
	<mailman.3784.1248709156.8015.python-list@python.org>
	<b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>
Message-ID: <4A6F0CBB.8050609@gmail.com>


> Matlab, from The Mathworks, has a companion product called Simulink.
> This allows the user to graphically build ?algorithms? in block form.
> There is a similar Python function.
>   
Where can I find a Python functionality like simulink  ?

thanks,
Stef Mientki





From cournape at gmail.com  Tue Jul 28 10:37:22 2009
From: cournape at gmail.com (David Cournapeau)
Date: Tue, 28 Jul 2009 23:37:22 +0900
Subject: Internal Math Library of Numpy
In-Reply-To: <d785f9cc0907280609w2e8d7cddgbf8b3850518e28bc@mail.gmail.com>
References: <d785f9cc0907280609w2e8d7cddgbf8b3850518e28bc@mail.gmail.com>
Message-ID: <5b8d13220907280737k43d2fad1k479f597e062176d2@mail.gmail.com>

On Tue, Jul 28, 2009 at 10:09 PM, Nanime Puloski<npuloski at gmail.com> wrote:
> Does Numpy use Python's standard math library when calculating
> elementary functions such as exp(x) and acos(x)?

It depends on the dtype: for fundamental types (float, int, etc...),
the underlying implementation is whatever the (C) math library
provides. If the functionality is not there, we have our own custom
implementation (but exp and acos happen to be mandatory - if they are
not detected, the build fail).

> Also, what is the
> internal library of Numpy and Python's standard math library? Is it
> platform independent?

I don't know for python, but for numpy, we have our own math library
on top of whatever the platform provides (which is not much on
windows, for example). There is an ongoing effort in numpy to provides
a portable, pure C (independent of the python runtime) math library.
The goal is to have a portable C99 math library, and more later
hopefully.

cheers,

David


From woakas at gfc.edu.co  Tue Jul 28 10:50:27 2009
From: woakas at gfc.edu.co (Gustavo =?iso-8859-1?Q?Andr=E9s?= Angulo)
Date: Tue, 28 Jul 2009 09:50:27 -0500
Subject: WSDL and XML generation
In-Reply-To: <3be39c48-6a89-4542-b08a-eaf00933b184@c1g2000yqi.googlegroups.com>
References: <3be39c48-6a89-4542-b08a-eaf00933b184@c1g2000yqi.googlegroups.com>
Message-ID: <20090728145027.GA11013@gfc.edu.co>

Hi you can generate the WSDl with soaplib [1], and you can view web.py or django
for this: 

for web.py -> http://webpy.org/cookbook/webservice

for django -> http://www.djangosnippets.org/snippets/979/


[1]=> http://trac.optio.webfactional.com/

> Hi all
> Newbie in Python, i am looking for some pointers (or better existing
> modules) to do the followings:
> 
> - generate (correct) XML messages from a WSDL file
> - make some modifications inside XML messages *before* sending them to
> the server hosting the Web services (described by previously
> mentionned WSDL file)
> - parse the answer.
> 
> Some ideas ?
> Thanks in advance
> Stephane
> -- 
> http://mail.python.org/mailman/listinfo/python-list
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 204 bytes
Desc: Digital signature
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/8205e2fb/attachment-0001.sig>

From python at mrabarnett.plus.com  Tue Jul 28 10:59:06 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 15:59:06 +0100
Subject: New implementation of re module
In-Reply-To: <h4lp5a$ehd$1@panix3.panix.com>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<h4lp5a$ehd$1@panix3.panix.com>
Message-ID: <4A6F123A.7030002@mrabarnett.plus.com>

Aahz wrote:
> In article <mailman.3787.1248712420.8015.python-list at python.org>,
> MRAB  <python at mrabarnett.plus.com> wrote:
>> I've been working on a new implementation of the re module. The details
>> are at http://bugs.python.org/issue2636, specifically from
>> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>> Python 2.6 on Windows if you want to try it out.
> 
> How does it handle the re module's unit tests?

Basically, it passes all those tests I expect it to pass. :-)

It fails those where the intended behaviour has changed, such as re.sub
treating unmatched groups as empty strings, as requested in
http://bugs.python.org/issue1519638.


From python at mrabarnett.plus.com  Tue Jul 28 11:11:02 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 16:11:02 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <200907281035.48713.hendrik@microcorp.co.za>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<mailman.3765.1248685391.8015.python-list@python.org>	<h4kepl$qhf$1@panix3.panix.com>
	<200907281035.48713.hendrik@microcorp.co.za>
Message-ID: <4A6F1506.9030207@mrabarnett.plus.com>

Hendrik van Rooyen wrote:
> On Monday 27 July 2009 16:49:25 Aahz wrote:
>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>
>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>> I have searched, but I can find nothing about this mediocre language.
>>>
>>> Could you tell us more?
>>>
>> :-P
>>
>> (For anyone who is confused by Hendrik's humor, he is saying that David
>> was referring to a programming language named "mediocre".  English
>> grammar is confusing!)
> 
> This is true - I intended, when I started the post, to make a crack about
> how he knew that he was mediocre - If there were some exam or test
> that you have to pass or fail to be able to make the claim to mediocrity.
> I was imagining a sort of devil's rating scale for programmers, that
> could cause one to say things like:  "I am studying hard so that I can
> get my mediocre certificate, and one day I hope to reach hacker rank".
> 
> And then the similarity to "I am a COBOL programmer" struck me, 
> and I abandoned the ratings.
> 
If you were a "COBOL" programmer, would you want to shout about it? :-)


From phillip.oldham at gmail.com  Tue Jul 28 11:15:49 2009
From: phillip.oldham at gmail.com (Phillip B Oldham)
Date: Tue, 28 Jul 2009 08:15:49 -0700 (PDT)
Subject: Suggestions for Python MapReduce?
References: <c1211435-8797-4177-b85a-3b58255e31ef@b15g2000yqd.googlegroups.com>
	<9786752b-4e1b-4ca2-8790-5547ba601647@t11g2000prh.googlegroups.com> 
	<123edb2e-882d-46b7-8081-0ca5d8798aab@k6g2000yqn.googlegroups.com> 
	<7xws60u06g.fsf@ruckus.brouhaha.com>
	<83889f6f-1e40-435e-b947-af17964e90af@d32g2000yqh.googlegroups.com>
Message-ID: <62d0b6e4-5356-4b53-b08b-9c99933d2c0f@s31g2000yqs.googlegroups.com>

In answer to my own question, I came across Octo.py[1] today. Not
tested/played-with/used it yet, however, though it seems simple
enough.

Still welcoming any suggestions for other/similar tools.

[1] http://code.google.com/p/octopy/


From dearmanzur at gmail.com  Tue Jul 28 11:17:25 2009
From: dearmanzur at gmail.com (Manzur Ahmed)
Date: Tue, 28 Jul 2009 11:17:25 -0400
Subject: need help using Tkinter
Message-ID: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>

i wanted to ask you if one of you could help me to use Tkinter. i'm trying
to just create a simple GUI for which I have provided the code for below.

# Simple GUI
# Demonstrates creating a window

from Tkinter import *

# create the root window
root = Tk ()

# modify the window
root.title("Simple GUI")
root.geometry("200x100")

# kick off the window's event loop
root.mainloop()

i saved the file as both simple_gui.py and simple_gui.pyw. when i try to run
simple_gui.pyw i don't get anything and when i try to run simple_gui.py i
get the following:
Traceback (most recent call last):
File "C:\Python-Study\Chapter10\simple_gui.py", line 4, in <module>
ImportError: No module named Tkinter

i tried to google search this and there were some threads that were saying
to install tcl but that does not work. I did check the Lib directory under
the Python directory and I did not see a Tkinter module anywhere which I
think is the problem. Do you know how I would go about with getting this
module and if that is not the problem or if you think it might be caused by
something else, can you please give me some guidance? i even reinstalled
python 3.1 which i got from www.python.org.  i still do not see the Tkinter
module in the lib directory.  thank you for all your help.

manzur
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/f14cc879/attachment-0001.html>

From hniksic at xemacs.org  Tue Jul 28 11:22:38 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Tue, 28 Jul 2009 17:22:38 +0200
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
	<fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>
Message-ID: <873a8gg7cx.fsf@busola.homelinux.net>

Bakes <bakes at ymail.com> writes:

>> > As a quick fix, you can add a file.flush() line after the
>> > file.write(...) line, and the problem should go away.
>>
>> Thank you very much, that worked perfectly.
>
> Actually, no it didn't. That fix works seamlessly in Linux, but gave
> the same error in a Windows environment. Is that expected?

Consider opening the file in binary mode, by passing the 'wb' and 'ab'
modes to open instead of 'w' and 'a' respectively.  On Windows, python
(and other languages) will convert '\n' to '\r\n' on write.


From python at mrabarnett.plus.com  Tue Jul 28 11:32:45 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 16:32:45 +0100
Subject: need help using Tkinter
In-Reply-To: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
Message-ID: <4A6F1A1D.7090604@mrabarnett.plus.com>

Manzur Ahmed wrote:
> i wanted to ask you if one of you could help me to use Tkinter. i'm 
> trying to just create a simple GUI for which I have provided the code 
> for below.
> 
> # Simple GUI
> # Demonstrates creating a window
> 
> from Tkinter import *
> 
> # create the root window
> root = Tk ()
> 
> # modify the window
> root.title("Simple GUI")
> root.geometry("200x100")
> 
> # kick off the window's event loop
> root.mainloop()
> 
> i saved the file as both simple_gui.py and simple_gui.pyw. when i try to 
> run simple_gui.pyw i don't get anything and when i try to run 
> simple_gui.py i get the following:
> Traceback (most recent call last):
> File "C:\Python-Study\Chapter10\simple_gui.py", line 4, in <module>
> ImportError: No module named Tkinter
> 
> i tried to google search this and there were some threads that were 
> saying to install tcl but that does not work. I did check the Lib 
> directory under the Python directory and I did not see a Tkinter module 
> anywhere which I think is the problem. Do you know how I would go about 
> with getting this module and if that is not the problem or if you think 
> it might be caused by something else, can you please give me some 
> guidance? i even reinstalled python 3.1 which i got from www.python.org 
> <http://www.python.org/>.  i still do not see the Tkinter module in the 
> lib directory.  thank you for all your help.
> 
There are some differences between Python 3.x and Python 2.x. In Python
3.1 the module is called "tkinter", not "Tkinter" (names are
case-sensitive).


From nagle at animats.com  Tue Jul 28 12:02:29 2009
From: nagle at animats.com (John Nagle)
Date: Tue, 28 Jul 2009 09:02:29 -0700
Subject: M2Crypto hangs on this URL
In-Reply-To: <fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
	<4a6e0c53$0$1644$742ec2ed@news.sonic.net>
	<fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>
Message-ID: <4a6f2067$0$1649$742ec2ed@news.sonic.net>

Martin P. Hellwig wrote:
> John Nagle wrote:
>> John Nagle wrote:
>>> John Nagle wrote:
>>>> There's something strange about this URL:
>>>>
>>>> "https://sagar310.pontins.com/sraep/"
...
> It looks to me like the SSL handshake is not done properly from the 
> server side.
> 
> Compare the output of:
> openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts 
> -msg
> 
> With (for example):
> openssl s_client -host www.google.com -port 443 -debug -showcerts -msg

   OpenSSL is clearly not happy with that site.  But it doesn't hang.

openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts  -msg

eventually prints

"Verify return code: 19 (self signed certificate in certificate chain)"
That's weird, because there's a Verisign certificate in the chain.
That site is somehow mishandling its certs.

My problem, though, is that M2Crypto 0.17 is hanging for hours to days
on those connections.

					John Nagle


From li.weidong at gmail.com  Tue Jul 28 12:16:57 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 09:16:57 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
	<mailman.3837.1248790649.8015.python-list@python.org>
Message-ID: <1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>

On Jul 28, 10:17?am, Christian Heimes <li... at cheimes.de> wrote:
> unicodedatais usually build as a shared library and not linked into the
> Python core. How did you configure Python? The usual prodecure is:
>
> ? ?./configure
> ? ?make
> ? ?sudo make install
>
> On Unix the preferred option for ./configure is "--enable-unicode=ucs4".
>
> Christian

Thanks for your response!  I configured it in the same way as you
said, but without "--enable-unicode=ucs4".  The ocnfig.log shows that
checking for UCS-4 was failed.  So I assume that by default UCS-2 was
used.  There was no other problme in the "make" step.

The problem was in the "sudo make install" step, where there were
errors in building libraries / test libraries that need unicodedata.so
which did not exist.

I also tried to use "make -i" to let it complete the building to
ignore that error.  In the end, I still did not see unicodedata.so in
the build result.  It seems that the Makefile did not even try to
build unicodedata.so.

Maybe something went wrong in my configuration?

- Weidong


From rylesny at gmail.com  Tue Jul 28 12:21:39 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 28 Jul 2009 09:21:39 -0700 (PDT)
Subject: Wrapping prstat on Solaris
References: <mailman.3776.1248704814.8015.python-list@python.org>
Message-ID: <1bce2ffd-85cb-4860-8b3e-92d8e1619a46@k19g2000yqn.googlegroups.com>

On Jul 27, 10:26?am, s... at pobox.com wrote:
> At work we currently use top to monitor ongoing system utilization on our
> Solaris systems. ?As time has moved on though, use of top has become
> problematic. ?Our admins want us to switch to prstat, Sun's top-like
> command. ?It works fine however doesn't emit a timestamp at each display
> interval, so it's essentially impossible looking at a prstat output
> file to determine when the particular "screen" was emitted.
>
> If figured, "No problem. ?I'll just write a little wrapper." ?Alas, that is
> proving harder than I thought. ?I can run prstat directing output to a file
> and it seems to blast out a block of lines every N seconds, but when run
> from inside a Python script I can't seem to make the damn thing not
> massively buffer its output. ?Accordingly, my script doesn't really see the
> output as its emitted, so the timestamp line it prepends to a block of
> output is off.
>
> I'm currently using subprocess.Popen like so:
>
> ? ? os.environ["TERM"] = "dumb"
> ? ? cmd = "prstat -c %s" % " ".join(sys.argv[1:])
> ? ? pipe = Popen(cmd, shell=True, bufsize=1, stdout=PIPE).stdout
>
> I've tried these other variants as well:
>
> ? * prefacing the prstat command with unbuffer (the tcl/expect thingamabob)
>
> ? * explicitly redirect the prstat output to /dev/stdout
>
> ? * setting bufsize to 0
>
> ? * used os.popen instead of Subprocess.Popen
>
> Nothing seems to help. ?I always seem to see about 30 seconds of data at
> once (I'm currently using a 5-second interval and 10 lines of output). ?I
> would have expected that prstat would simply flush stdout after each block
> of output.
>
> Any ideas about how to get prstat to cooperate better?
>
> Thanks,
>
> --
> Skip Montanaro - s... at pobox.com -http://www.smontanaro.net/
> ? ? That's more than a dress. That's an Audrey Hepburn movie. -- Jerry Maguire

Hey Skip,

You haven't told us how you are actually reading from prstat's output
pipe, which may be the cause. For instance, if you are doing

for line in pipe:
  print line
  ...

then this could cause your buffering issue.

Instead try using readline():

while True:
  line = pipe.readline()
  ...


From daniel.harjanto at gmail.com  Tue Jul 28 12:30:26 2009
From: daniel.harjanto at gmail.com (misterdi)
Date: Tue, 28 Jul 2009 09:30:26 -0700 (PDT)
Subject: Python as active script <script language=python>
Message-ID: <862eed23-2aea-4e9f-977a-6afd0bfa24a3@x25g2000prf.googlegroups.com>

I'm using Activestate python,
For older version of python, I know that we can register python as
active script by registering it through win32comext.axscript.client
pyscript.py
And to do that I need to change something in this pyscript.py before
running pyscript_rexec.py(http://fastq.com/~sckitching/Python/
win32_activeX_pyscript.htm),
but I can't find similar thing with python 2.6.2

I can't find the line that need to be changed.

Can someone kindly show me how to enable python26 as an active script
for IE?

Thanks,


From rylesny at gmail.com  Tue Jul 28 12:31:28 2009
From: rylesny at gmail.com (ryles)
Date: Tue, 28 Jul 2009 09:31:28 -0700 (PDT)
Subject: The longest word
References: <daa44413-f7b2-4972-9506-3a036b74604b@a26g2000yqn.googlegroups.com>
	<99e6020c-766e-46bc-bd16-fac09112288b@c1g2000yqi.googlegroups.com> 
	<aad740f9-f520-4379-b2e1-8564644d0495@w6g2000yqw.googlegroups.com> 
	<m2my6p9mj5.fsf@cs.uu.nl> <87prblul0l.fsf@busola.homelinux.net> 
	<c8ff2ba2-b62b-40e8-ae7e-b78cac491812@s31g2000yqs.googlegroups.com>
Message-ID: <feb4e6af-39a3-42a2-9b12-63e986408559@d4g2000yqa.googlegroups.com>

On Jul 28, 7:55?am, NiklasRTZ <nikla... at gmail.com> wrote:

> Sincere thanks for strengthening python's superior flexibility. Same
> function also works around an exploding index problem returning
> results for longest word where otherwise a word with whitespace
> crashes the index:

Babelfish?



From davea at ieee.org  Tue Jul 28 12:36:56 2009
From: davea at ieee.org (Dave Angel)
Date: Tue, 28 Jul 2009 12:36:56 -0400
Subject: FTP Offset larger than file.
In-Reply-To: <fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>	<87ljm8vrcf.fsf@busola.homelinux.net>	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
	<fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com>
Message-ID: <4A6F2928.5000800@ieee.org>

Bakes wrote:
> On 28 July, 15:18, Bakes <ba... at ymail.com> wrote:
>   
>> On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
>>
>>
>>
>>     
>>> Bakes <ba... at ymail.com> writes:
>>>       
>>>> The error I get is:
>>>> ftplib.error_temp: 451-Restart offset 24576 is too large for file size
>>>> 22852.
>>>> 451 Restart offset reset to 0
>>>> which tells me that the local file is larger than the external file,
>>>> by about a kilobyte. Certainly, the local file is indeed that size, so
>>>> my local script is doing the right things. I do wonder what is going
>>>> wrong, can anyone enlighten me?
>>>>         
>>> I'd say you failed to take buffering into account.  You write into a
>>> buffered file, yet you use os.path.getsize() to find out the current
>>> file size.  If the data is not yet flushed, you keep re-reading the same
>>> stuff from the remote file, and writing it out.  Once the buffer is
>>> flushed, your file will contain more data than was retrieved from the
>>> remote side, and eventually this will result in the error you see.
>>>       
>>> As a quick fix, you can add a file.flush() line after the
>>> file.write(...) line, and the problem should go away.
>>>       
>> Thank you very much, that worked perfectly.
>>     
>
> Actually, no it didn't. That fix works seamlessly in Linux, but gave
> the same error in a Windows environment. Is that expected?
>
>   
This is a text file you're transferring.  And you didn't specify "wb".  
So the Windows size will be larger than the Unix size, since you're 
expanding the newline characters.

getsize() is looking at the size after newlines are expanded to 0d0a, 
while The remote file, presumably a Unix system likely has just has 0a.

I think you'd do best just keeping track of the bytes you've written.


DaveA


From lists at cheimes.de  Tue Jul 28 12:37:36 2009
From: lists at cheimes.de (Christian Heimes)
Date: Tue, 28 Jul 2009 18:37:36 +0200
Subject: Questions about unicodedata in python 2.6.2
In-Reply-To: <1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>	<mailman.3837.1248790649.8015.python-list@python.org>
	<1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>
Message-ID: <h4n9gh$jrt$1@ger.gmane.org>

Weidong wrote:
> Thanks for your response!  I configured it in the same way as you
> said, but without "--enable-unicode=ucs4".  The ocnfig.log shows that
> checking for UCS-4 was failed.  So I assume that by default UCS-2 was
> used.  There was no other problme in the "make" step.

Correct

> The problem was in the "sudo make install" step, where there were
> errors in building libraries / test libraries that need unicodedata.so
> which did not exist.

'make install' shouldn't compile any libraries if you run 'make' prior
to 'make install'. I suggest you start again with a clean build tree of
Python 2.6.2.

Christian



From chris.arndt at web.de  Tue Jul 28 13:07:26 2009
From: chris.arndt at web.de (Christopher Arndt)
Date: Tue, 28 Jul 2009 10:07:26 -0700 (PDT)
Subject: New implementation of re module
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<mailman.3792.1248722883.8015.python-list@python.org>
Message-ID: <a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>

On 27 Jul., 21:27, Wolfgang Rohdewald <wolfg... at rohdewald.de> wrote:
> how do I compile _regex.c on Linux?

This simple setup.py file should do the trick:

from distutils.core import setup, Extension

setup(name='regex',
    version='1.0',
    py_modules = ['regex'],
    ext_modules=[Extension('_regex', ['_regex.c'])],
)

Also, you need to copy "unicodedata_db.h" from the "Modules" directory
of the Python source tree to your working directory, since this file
apparently is not installed into the include directory of a Python
installation.

I get an error for Python 2.5 on Mac OS X 10.4 and Linux though. Seems
that the module is not compatible with Python 2.5.

_regex.c: In function 'getstring':
_regex.c:2425: error: invalid type argument of '->'
_regex.c: In function 'getstring':
_regex.c:2425: error: invalid type argument of '->'
lipo: can't figure out the architecture type of: /var/tmp//
ccT3oDXD.out
error: command 'gcc' failed with exit status 1

resp. on Linux:

_regex.c: In function 'getstring':
_regex.c:2425: warning: implicit declaration of function 'Py_TYPE'
_regex.c:2425: error: invalid type argument of '->'
_regex.c: In function 'get_match_replacement':
_regex.c:2900: warning: implicit declaration of function
'PyLong_AsSsize_t'
error: command 'gcc' failed with exit status 1

With the official Python 2.6 distribution for Mac OS X it works.

Chris


From python at mrabarnett.plus.com  Tue Jul 28 13:25:43 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 18:25:43 +0100
Subject: New implementation of re module
In-Reply-To: <a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<mailman.3792.1248722883.8015.python-list@python.org>
	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
Message-ID: <4A6F3497.3010602@mrabarnett.plus.com>

Christopher Arndt wrote:
> On 27 Jul., 21:27, Wolfgang Rohdewald <wolfg... at rohdewald.de> wrote:
>> how do I compile _regex.c on Linux?
> 
> This simple setup.py file should do the trick:
> 
> from distutils.core import setup, Extension
> 
> setup(name='regex',
>     version='1.0',
>     py_modules = ['regex'],
>     ext_modules=[Extension('_regex', ['_regex.c'])],
> )
> 
> Also, you need to copy "unicodedata_db.h" from the "Modules" directory
> of the Python source tree to your working directory, since this file
> apparently is not installed into the include directory of a Python
> installation.
> 
> I get an error for Python 2.5 on Mac OS X 10.4 and Linux though. Seems
> that the module is not compatible with Python 2.5.
> 
> _regex.c: In function 'getstring':
> _regex.c:2425: error: invalid type argument of '->'
> _regex.c: In function 'getstring':
> _regex.c:2425: error: invalid type argument of '->'
> lipo: can't figure out the architecture type of: /var/tmp//
> ccT3oDXD.out
> error: command 'gcc' failed with exit status 1
> 
> resp. on Linux:
> 
> _regex.c: In function 'getstring':
> _regex.c:2425: warning: implicit declaration of function 'Py_TYPE'
> _regex.c:2425: error: invalid type argument of '->'
> _regex.c: In function 'get_match_replacement':
> _regex.c:2900: warning: implicit declaration of function
> 'PyLong_AsSsize_t'
> error: command 'gcc' failed with exit status 1
> 
> With the official Python 2.6 distribution for Mac OS X it works.
> 
The source code is intended to replace the current 're' module in Python
2.7 (and I'll be porting it to Python 3.2), so I'm not that worried
about Python versions earlier than 2.6 for testing, although if there's
sufficient need then I could tweak the sources for 2.5.


From lemmath at gmail.com  Tue Jul 28 14:02:16 2009
From: lemmath at gmail.com (Vincent Vega)
Date: Tue, 28 Jul 2009 11:02:16 -0700 (PDT)
Subject: Print value CLOB via cx_Oracle
Message-ID: <6de8842b-f1c6-460e-a705-4f6dbd81492c@a26g2000yqn.googlegroups.com>

Hi,

I call function in Oracle database use cx_Oracle.
In standard I define:

db       = cx_Oracle.connect(username, password, tnsentry)
cursor  = db.cursor()

I create variable 'y' (result function 'fun_name') and call function
'fun_name':

y   = cursor.var(cx_Oracle.CLOB)
cursor.callfunc(fun_name, cx_Oracle.CLOB, y)

When I print variable 'y' I receive:
<cx_Oracle.CLOB with value <cx_Oracle.LOB object at 0x00999999>>

How can I get value variable 'y'???
How read <cx_Oracle.LOB object at 0x00999999>???


Vincent Vega




Note:
Off course y.read() does not work, cause 'y'is CLOB not LOB.
(see datatypes table in site: http://www.oracle.com/technology/pub/articles/prez-python-queries.html)





From martin.hellwig at dcuktec.org  Tue Jul 28 14:21:32 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Tue, 28 Jul 2009 19:21:32 +0100
Subject: M2Crypto hangs on this URL
In-Reply-To: <4a6f2067$0$1649$742ec2ed@news.sonic.net>
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
	<4a6deda5$0$1639$742ec2ed@news.sonic.net>
	<4a6e0c53$0$1644$742ec2ed@news.sonic.net>
	<fOadnWLTDuSlhfPXnZ2dnUVZ8qudnZ2d@bt.com>
	<4a6f2067$0$1649$742ec2ed@news.sonic.net>
Message-ID: <eu-dnRYQS6Qx3PLXnZ2dnUVZ8tRi4p2d@bt.com>

John Nagle wrote:
> Martin P. Hellwig wrote:
>> John Nagle wrote:
>>> John Nagle wrote:
>>>> John Nagle wrote:
>>>>> There's something strange about this URL:
>>>>>
>>>>> "https://sagar310.pontins.com/sraep/"
> ...
>> It looks to me like the SSL handshake is not done properly from the 
>> server side.
>>
>> Compare the output of:
>> openssl s_client -host sagar310.pontins.com -port 443 -debug 
>> -showcerts -msg
>>
>> With (for example):
>> openssl s_client -host www.google.com -port 443 -debug -showcerts -msg
> 
>   OpenSSL is clearly not happy with that site.  But it doesn't hang.
> 
> openssl s_client -host sagar310.pontins.com -port 443 -debug -showcerts  
> -msg
> 
> eventually prints
> 
> "Verify return code: 19 (self signed certificate in certificate chain)"
> That's weird, because there's a Verisign certificate in the chain.
> That site is somehow mishandling its certs.
> 
> My problem, though, is that M2Crypto 0.17 is hanging for hours to days
> on those connections.
> 
>                     John Nagle

Well it hanged when I tried it, however the site now does return 
something when using Firefox, so I assume somebody is doing some work 
there or the server decided to do something else.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From varun.cent at gmail.com  Tue Jul 28 14:22:00 2009
From: varun.cent at gmail.com (varun)
Date: Tue, 28 Jul 2009 23:52:00 +0530
Subject: Language detector for Python using en-gram.
Message-ID: <1c7eb5470907281122v4c080c6bm2357173bb3f7e1fd@mail.gmail.com>

One of my friend suggested me to do a language detector for python.At
present the language detector in python is in uni-gram mode and i have
planned to do it in en-gram mode.Kindly give me your suggestion as i am
doing this as my final year project.


With Anticipation,

Varun V. Kumar
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/150df3f9/attachment-0001.html>

From fengmang_python at sina.com  Tue Jul 28 14:41:57 2009
From: fengmang_python at sina.com (fengmang_python at sina.com)
Date: Wed, 29 Jul 2009 02:41:57 +0800 
Subject: C function taking double pointer to a structure variable as OUTPUT
	parameter
Message-ID: <20090728184157.B0F5010C1D53@mail3-11.sinamail.sina.com.cn>

Hi, Everyone,
I am a newbie to both Swig and Python. I am trying to export a set of C APIs to Python. 
My C function is 
int getInfor( char* name, int height, int weight, Infor** infor) //where infor is an OUTPUT parameter
{
......
*infor = (Infor*)malloc(sizeof(Infor));
......
}
&nbsp;
The declare of structure Infor is :
&nbsp;typedef struct {
&nbsp;char&nbsp;&nbsp;name[20];
&nbsp;int&nbsp;&nbsp;&nbsp;height;
&nbsp;int&nbsp;&nbsp;&nbsp;weight;
} Infor
&nbsp;
When wrote the below lines in the interface file named Extest.i
%module Extest
%{
#include "Extest.h"
%}
%typemap(out) Infor **OUTPUT {Infor **c}
%apply int *OUTPUT {int *c}
%include "Extest.h"
&nbsp;
And then, How to write testing python file to call the function named getInfor()?
such as in test.py
&nbsp;
infor = Extest.Infor()
res = Extest.getInfor("Test Name", 175, 80, infor)
&nbsp;
when run upper's test.py, Error occured. The message is 
TypeError: in method 'getInfor', argument 4 of type 'Infor **'
&nbsp;
How to write the test.py to transfer the&nbsp; 'Infor **' type's parameter?
After putting lot of trail and errors, I am writing this mail.
Could you please help me to write the test.py or swig interface file for the above function?
Thank you,
jemmy
Awaiting you
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/11c88104/attachment-0001.html>

From 71david at libero.it  Tue Jul 28 14:44:32 2009
From: 71david at libero.it (David)
Date: Tue, 28 Jul 2009 20:44:32 +0200
Subject: Gracefully exiting CLI application
References: <1jh923agd88bc$.3z8qrldkivi8$.dlg@40tude.net>
	<pan.2009.07.28.13.31.56.265000@nowhere.com>
Message-ID: <t36oxhy765vj.dpzs2pnx155b.dlg@40tude.net>

Il Tue, 28 Jul 2009 14:31:56 +0100, Nobody ha scritto:

> Killed by what means?
> 
> Ctrl-C sends SIGINT which is converted to a KeyboardInterrupt exception.
> This can be caught, or if it's allowed to terminate the process, any exit
> handlers registered via atexit.register() will be used.
> 
> For other signals, you can install a handler with signal.signal(). This
> can call sys.exit() or raise an exception (e.g. KeyboardInterrupt).
> 
> OTOH, if the process is terminated by SIGKILL, there's nothing you can do
> about it. And although it's possible to trap SIGSEGV, you shouldn't assume
> that the Python interpreter is still functional at this point.

I'm really sorry guys, I forgot to mention that the platform is win32, where
there is minimal support to signals.

Anyway I've found a solution with win32api.SetConsoleCtrlHandler that
installs a event handler which traps all windows events, CTRL_CLOSE_EVENT,
CTRL_LOGOFF_EVENT, and CTRL_SHUTDOWN_EVENT included.

David.


From malkia at mac.com  Tue Jul 28 14:46:38 2009
From: malkia at mac.com (Dimiter "malkia" Stanev)
Date: Tue, 28 Jul 2009 11:46:38 -0700
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<17pco71asfk7d.1kd4oiidz6nqy.dlg@40tude.net>
	<5gi665hk6ggn0a48o7qd4h3p16phe959hc@4ax.com>
	<19d4rlsscvrgw.xu0laoyvg0$.dlg@40tude.net>
	<361bee02-b7aa-4475-968b-db8d88deb8d8@x25g2000prf.googlegroups.com>
	<4a6905b0$0$27110$a729d347@news.telepac.pt>
	<a0a385f3-26cd-4dca-bceb-4496ea4e6b16@l34g2000vba.googlegroups.com>
	<h4ctjv$bhj$1@news.eternal-september.org>
	<aa1c904a-3507-4172-9664-17d275f95db6@x25g2000prf.googlegroups.com>
	<aa9f79fa-beae-46d1-a00f-d01c0559ad1f@v15g2000prn.googlegroups.com>
Message-ID: <h4nh2f$bl5$2@malkia.motzarella.org>

Xah Lee wrote:

> PHP is functional.

PHP is functional, as in "it functions!". PHP is not functional, as in 
"it ain't functions!"


From djames.suhanko at gmail.com  Tue Jul 28 15:27:24 2009
From: djames.suhanko at gmail.com (Djames Suhanko)
Date: Tue, 28 Jul 2009 16:27:24 -0300
Subject: Discovery IP in connection
In-Reply-To: <m2ws5taexq.fsf@cs.uu.nl>
References: <mailman.3797.1248726749.8015.python-list@python.org>
	<m2ws5taexq.fsf@cs.uu.nl>
Message-ID: <fd9e6bba0907281227l604201afx97d79bca5bd91385@mail.gmail.com>

Thanks, all!
 I didn't tried to print addr. :-(
 sorry all. I'm learning python yet.
Thanks again !

On Mon, Jul 27, 2009 at 8:23 PM, Piet van Oostrum<piet at cs.uu.nl> wrote:
>>>>>> Djames Suhanko <djames.suhanko at gmail.com> (DS) wrote:
>
>>DS> Hello,all!
>>DS> ?I wrote a little programa that listening UDP packets. A can receive
>>DS> the messages, but I can't see the the origin IP.
>>DS> ?How can I to ?get the remote IP address in connection?
>
> What do you think the addr is for in
> data, addr = mySocket.recvfrom(100)?
>
>>DS> My source:
>
>>DS> #!/usr/bin/env python
>>DS> import socket
>>DS> mySocket = socket.socket ( socket.AF_INET, socket.SOCK_DGRAM )
>>DS> mySocket.bind ( ( '', 514 ) )
>
>>DS> data, addr = mySocket.recvfrom(100)
>>DS> print data
>
> --
> Piet van Oostrum <piet at cs.uu.nl>
> URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
> Private email: piet at vanoostrum.org
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Djames Suhanko
LinuxUser 158.760


From piet at cs.uu.nl  Tue Jul 28 15:44:05 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Tue, 28 Jul 2009 21:44:05 +0200
Subject: bad certificate error
References: <mailman.3835.1248788885.8015.python-list@python.org>
	<332a5bba-48d5-4c8b-9c1e-288790d85dbb@o32g2000yqm.googlegroups.com>
Message-ID: <m263dca8ze.fsf@cs.uu.nl>

>>>>> jakecjacobson <jakecjacobson at gmail.com> (j) wrote:

>j> On Jul 28, 9:48?am, Jean-Paul Calderone <exar... at divmod.com> wrote:
>>> On Tue, 28 Jul 2009 03:35:55 -0700 (PDT), jakecjacobson <jakecjacob... at gmail.com> wrote:
>>> > [snip]
>>> 
>>> >"Invalid how? ?Self signed certificate? Domain mismatch? Expired
>>> >certificate?" ?It is a server name mismatch.
>>> 
>>> Python 2.4 is not capable of allowing you to customize this verification
>>> behavior. ?It is hard coded to let OpenSSL make the decision about whether
>>> to accept the certificate or not.
>>> 
>>> Either M2Crypto or pyOpenSSL will let you ignore verification errors. ?The
>>> new ssl module in Python 2.6 may also as well.
>>> 
>>> Jean-Paul

>j> Thanks, I will look into these suggestions.


>j> 		# cert_file is a PEM formatted certificate chain file.
>j> 		connection = httplib.HTTPSConnection(host, int(port), key_file,
>j> cert_file)

What happens if you set cert_file to None? This would indicate that you
are not interested in the server's certificate.

By the way, is the cert_file you supply the certificate of the CA that
signed the server's cert (in contrast to yours)?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From lkcl at lkcl.net  Tue Jul 28 15:56:29 2009
From: lkcl at lkcl.net (Luke Kenneth Casson Leighton)
Date: Tue, 28 Jul 2009 19:56:29 +0000
Subject: [ANN] Pyjamas 0.6pre2 Python Web Widget Set and Javascript Compiler
Message-ID: <ced5f0f60907281256m19ac88c9n8231991593352116@mail.gmail.com>

http://pyjs.org

this is a pre-release announcement, 0.6pre2, of the pyjamas widget set
and python-to-javascript compiler.  there are over 110 entries in the
CHANGELOG since the last stable release, 0.5p1, and so it was deemed
sensible to invite people to test this version before its next stable
release, 0.6.

pyjamas, being a port of GWT to python, comprises four main components:
* a stand-alone python-to-javascript compiler
* a desktop-based wrapper around python-xpcom or pywebkitgtk
* a browser "DOM" model wrapper interface
* a widget set similar to pygtk2 / pyqt4, based on DOM manipulation

significantly in the 0.6 series, pyjamas-desktop has been incorporated
into the build: "python Hello.py" will start a stand-alone app (just
as you would with pygtk2 or pyqt4) and "pyjsbuild Hello" will compile
the javascript version(s).

the combination means that pyjamas can run python applications -
unmodified - in all major web browsers, or on the desktop (using gecko
or webkit) in a similar fashion to adobe AIR.

in the javascript version: somewhere along the line, a massive
performance hit was introduced by accident. this has now been fixed.
however, random desperate attempts to improve performance, before the
mistake was corrected, mean that the pyjamas 0.6pre2
python-to-javascript compiler produces code that is stunningly quick.

also in the 0.6pre2 release, "strict" python options have now been
introduced, so that developers can expect much more support for the
standard python 2.5 / 2.6 language semantics.  the "-O" option
disables many of these features, bringing a quite significant speed
increase, by sacrificing python compatibility.  that's just the way it
has to be.

downloads can be found by following the links from http://pyjs.org -
sourceforge, code.google.com, pypi, all the usual places.

lastly - thank you to everyone who's helped with pyjamas: bernd,
bernd, jurgen, christian, kees, ondrej and many more, and especially
thank you to the people who helped out by pointing out bugs in the
0.6pre1 release, please keep it up!

l.


From electriclightheads at gmail.com  Tue Jul 28 15:59:37 2009
From: electriclightheads at gmail.com ('2+)
Date: Wed, 29 Jul 2009 04:59:37 +0900
Subject: instead of depending on data = array('h') .. write samples 1 by 1 to 
	w = wave.open("wav.wav", "w")
Message-ID: <1078018b0907281259m63d9cbeeyb6f908f240afa6a2@mail.gmail.com>

it says
Wave_write.writeframes(data)
will that mean
"from array import array"
is a must?

this does the job:

import oil
import wave
from array import array

a = oil.Sa()

w = wave.open("current.wav", "w")
w.setnchannels(2)
w.setsampwidth(2)
w.setframerate(44100)

data = array('h')

for gas in range(44100 * 5):
    a.breath()
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    data.append(r)
    data.append(l)

w.writeframes(data.tostring())
w.close()

don't like array becoming so huge so tested this and it was also okay:

for gas in range(44100 * 5):
    a.breath()
    data = array('h')
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    data.append(r)
    data.append(l)
    w.writeframes(data.tostring())

but without array .. it becomes 15secs(3 times longer than was
intended to be) of wav file:

for gas in range(44100 * 5):
    a.breath()
    r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
    l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
    w.writeframes(hex(r))
    w.writeframes(hex(l))

should i just be happy with depennding on using array?
or is there a solution to make the last one work properly?

tia

-- 
SaRiGaMa's Oil Vending Orchestra
is podcasting:
http://sarigama.namaste.jp/podcast/rss.xml
and supplying oil.py for free:
http://oilpy.blogspot.com/


From leerisq at gmail.com  Tue Jul 28 16:05:16 2009
From: leerisq at gmail.com (LeeRisq)
Date: Tue, 28 Jul 2009 13:05:16 -0700 (PDT)
Subject: xlrd - insert column?
Message-ID: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>

Does xlrd have the capability to insert a column?


From wilk at flibuste.net  Tue Jul 28 16:05:35 2009
From: wilk at flibuste.net (William Dode)
Date: 28 Jul 2009 20:05:35 GMT
Subject: New implementation of re module
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<mailman.3792.1248722883.8015.python-list@python.org>
	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
	<mailman.3850.1248801945.8015.python-list@python.org>
Message-ID: <4a6f5a0f$0$25500$426a74cc@news.free.fr>

On 28-07-2009, MRAB wrote:

> With the official Python 2.6 distribution for Mac OS X it works.
>> 
> The source code is intended to replace the current 're' module in Python
> 2.7 (and I'll be porting it to Python 3.2), so I'm not that worried
> about Python versions earlier than 2.6 for testing, although if there's
> sufficient need then I could tweak the sources for 2.5.

I understand now why i could'nt compile it !

So, i would like if it's not too much work for you.

-- 
William Dod? - http://flibuste.net
Informaticien Ind?pendant


From bsagert at gmail.com  Tue Jul 28 16:16:30 2009
From: bsagert at gmail.com (Bill)
Date: Tue, 28 Jul 2009 13:16:30 -0700 (PDT)
Subject: Need help in passing a "-c command" argument to the interactive 
	shell.
Message-ID: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>

On my windows box I type => c:\x>python -c "import re"

The result is => c:\x>

In other words, the Python interactive shell doesn't even open. What
am I doing wrong?

I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
argument passing, but to no avail.


From doug.farrell at gmail.com  Tue Jul 28 16:21:47 2009
From: doug.farrell at gmail.com (writeson)
Date: Tue, 28 Jul 2009 13:21:47 -0700 (PDT)
Subject: Extract images from PDF files
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
	<mailman.3815.1248752499.8015.python-list@python.org>
Message-ID: <bb3c4944-596f-478f-8c34-0478fbbbe9dd@q35g2000vbi.googlegroups.com>

David,

Thanks for your reply, I'll take a look at pdftohtml and see if it
suits my needs.

Thanks!
Doug


From insyte at gmail.com  Tue Jul 28 16:24:15 2009
From: insyte at gmail.com (Ben)
Date: Tue, 28 Jul 2009 13:24:15 -0700 (PDT)
Subject: time.strftime('%m-%d-%Y %H:%m:%S') to log is out of order
References: <e17023ac-0ec1-4bd8-af04-dfb487b7f125@i6g2000yqj.googlegroups.com>
	<146e1535-268c-42ff-8d86-09c2fa4bbd1c@h21g2000yqa.googlegroups.com> 
	<dcbef29e-db96-4ab2-9cf4-61abc8fa7f0d@k26g2000vbp.googlegroups.com> 
	<16e1d810-bdf0-46b8-aef1-7e57eeb30547@k19g2000yqn.googlegroups.com> 
	<524a57a9-ba45-459b-b62d-81f527888a4e@j19g2000vbp.googlegroups.com>
Message-ID: <8d2e92fd-a7a1-40fb-8586-808c29dee31c@d32g2000yqh.googlegroups.com>

On Jul 22, 1:04?pm, davidj411 <davidj... at gmail.com> wrote:

> i think "Piet van Oostrum" has resolved my issue.
> good eyes!

Well, he *is* Dutch...

-Ben


From vs at it.uu.se  Tue Jul 28 16:28:09 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Tue, 28 Jul 2009 22:28:09 +0200
Subject: "Deprecated sets module" with Python 2.6
Message-ID: <4A6F5F59.4080507@it.uu.se>

I would appreciate help on correcting a problem when trying to create an 
*.exe file using py2exe via GUI2exe with Python 2.6.2.

When using GUI2exe to create an *.exe I always get the following warning 
during the compile process:

 C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
 DeprecationWarning: the sets module is deprecated
 import sets

and this results in the creation of an *.exe file that can not be executed.

On the other hand, if I use the same procedure (on the same Python code) 
with
Python 2.5, there are no warnings and the *.exe works fine.

The procedure used is that given in the example "Less simpler one" at
 
  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin

Any suggestions, help, ... would be greatly appreciated.

Thanks,
--V.



From tino at wildenhain.de  Tue Jul 28 16:36:57 2009
From: tino at wildenhain.de (Tino Wildenhain)
Date: Tue, 28 Jul 2009 22:36:57 +0200
Subject: xlrd - insert column?
In-Reply-To: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>
References: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>
Message-ID: <4A6F6169.6030409@wildenhain.de>

LeeRisq wrote:
> Does xlrd have the capability to insert a column?

rd means ReaD, so there is nothing it could insert
something to. Of course once you have read the data
you can manipulate its structure how you like it.

The counterpart is xlwt and it can write excel files
however you like it.

Regards
Tino


From philip at semanchuk.com  Tue Jul 28 16:45:08 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Tue, 28 Jul 2009 16:45:08 -0400
Subject: Need help in passing a "-c command" argument to the interactive
	shell.
In-Reply-To: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
References: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
Message-ID: <8ACF1BB9-CC8B-4D3C-88D3-6A81C56F99A9@semanchuk.com>


On Jul 28, 2009, at 4:16 PM, Bill wrote:

> On my windows box I type => c:\x>python -c "import re"
>
> The result is => c:\x>
>
> In other words, the Python interactive shell doesn't even open. What
> am I doing wrong?

Nothing! =) The -c option tells Python to execute the commands in the  
quotes as a Python program. It's as if you wrote a Python program that  
contained only "import re" and then executed that program.

If you want to run the Python interpreter interactively, just type  
"python" (no quotes) at the command prompt and hit enter.


> I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
> argument passing, but to no avail.

Yikes, that's the documentation for Python 1.5.2 which is nine years  
old! If that's the version you're running, then it's appropriate to  
read that documentation, but that's probably not the case.

"python --version" (again, no quotes) should tell you what version  
you're running.

HTH
Philip



From mark at markroseman.com  Tue Jul 28 16:47:14 2009
From: mark at markroseman.com (Mark Roseman)
Date: Tue, 28 Jul 2009 14:47:14 -0600
Subject: need help using Tkinter
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
	<mailman.3847.1248795167.8015.python-list@python.org>
Message-ID: <mark-906AAB.14471428072009@nothing.attdns.com>

 MRAB <python at mrabarnett.plus.com> wrote:
> Manzur Ahmed wrote:
> > i wanted to ask you if one of you could help me to use Tkinter. i'm 
> > trying to just create a simple GUI for which I have provided the code 
> > for below.
> There are some differences between Python 3.x and Python 2.x. In Python
> 3.1 the module is called "tkinter", not "Tkinter" (names are
> case-sensitive).


Further to the above, you can find my Tkinter tutorial (which uses 
Python 3.x) at http://www.tkdocs.com -- I hope this will provide some 
help in getting up to speed.

Mark


From python at mrabarnett.plus.com  Tue Jul 28 16:47:45 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 21:47:45 +0100
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <4A6F5F59.4080507@it.uu.se>
References: <4A6F5F59.4080507@it.uu.se>
Message-ID: <4A6F63F1.4080502@mrabarnett.plus.com>

Virgil Stokes wrote:
> I would appreciate help on correcting a problem when trying to create an 
> *.exe file using py2exe via GUI2exe with Python 2.6.2.
> 
> When using GUI2exe to create an *.exe I always get the following warning 
> during the compile process:
> 
> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
> DeprecationWarning: the sets module is deprecated
> import sets
> 
> and this results in the creation of an *.exe file that can not be executed.
> 
> On the other hand, if I use the same procedure (on the same Python code) 
> with
> Python 2.5, there are no warnings and the *.exe works fine.
> 
> The procedure used is that given in the example "Less simpler one" at
> 
>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
> 
> Any suggestions, help, ... would be greatly appreciated.
> 
The 'sets' module is deprecated in Python 2.6 because 'set' was added as
a new builtin class. I don't know why that would result in a .exe file
that can't be executed.


From breamoreboy at yahoo.co.uk  Tue Jul 28 16:49:53 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Tue, 28 Jul 2009 21:49:53 +0100
Subject: Need help in passing a "-c command" argument to the interactive
	shell.
In-Reply-To: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
References: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
Message-ID: <h4no8c$5rm$1@ger.gmane.org>

Bill wrote:
> On my windows box I type => c:\x>python -c "import re"
> 
> The result is => c:\x>
> 
> In other words, the Python interactive shell doesn't even open. What
> am I doing wrong?
> 
> I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
> argument passing, but to no avail.
You've told python to run the command "import re" which it's happily 
done before exiting.  Simply type python, then at the prompt (default 
 >>>) type whatever commands you wish, e.g.

c:\Users\Mark\python\regex>python
Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit 
(Intel)] on
win32
Type "help", "copyright", "credits" or "license" for more information.
 >>> import re
 >>> help(re.compile)
Help on function compile in module re:

compile(pattern, flags=0)
     Compile a regular expression pattern, returning a pattern object.

 >>>

-- 
Kindest regards.

Mark Lawrence.



From shai at platonix.com  Tue Jul 28 16:49:57 2009
From: shai at platonix.com (Shai)
Date: Tue, 28 Jul 2009 13:49:57 -0700 (PDT)
Subject: Override a method but inherit the docstring
References: <87r5wggm0y.fsf@benfinney.id.au> <87ljmogglz.fsf@benfinney.id.au> 
	<02701ee5$0$5185$c3e8da3@news.astraweb.com>
	<056f629b-aa63-458a-ae16-ac40a759e446@h11g2000yqb.googlegroups.com>
	<h4hu96$8hs$1@panix3.panix.com>
Message-ID: <db31afcb-0ff5-4a1d-a295-1b0830256913@a26g2000yqn.googlegroups.com>

On Jul 26, 6:55?pm, a... at pythoncraft.com (Aahz) wrote:
>
> Nice! ?Maybe stick this on the Cookbook?

http://code.activestate.com/recipes/576862/

Thanks for the suggestion,

Shai.


From aahz at pythoncraft.com  Tue Jul 28 16:57:37 2009
From: aahz at pythoncraft.com (Aahz)
Date: 28 Jul 2009 13:57:37 -0700
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<h4lp5a$ehd$1@panix3.panix.com>
	<mailman.3843.1248793153.8015.python-list@python.org>
Message-ID: <h4noo1$kr6$1@panix3.panix.com>

In article <mailman.3843.1248793153.8015.python-list at python.org>,
MRAB  <python at mrabarnett.plus.com> wrote:
>Aahz wrote:
>> In article <mailman.3787.1248712420.8015.python-list at python.org>,
>> MRAB  <python at mrabarnett.plus.com> wrote:
>>> I've been working on a new implementation of the re module. The details
>>> are at http://bugs.python.org/issue2636, specifically from
>>> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>>> Python 2.6 on Windows if you want to try it out.
>> 
>> How does it handle the re module's unit tests?
>
>Basically, it passes all those tests I expect it to pass. :-)
>
>It fails those where the intended behaviour has changed, such as re.sub
>treating unmatched groups as empty strings, as requested in
>http://bugs.python.org/issue1519638.

Then you should definitely publish to PyPI and post a message to
c.l.py.announce to get more users.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From REMOVEmagicus23THIS at gmail.com  Tue Jul 28 17:25:09 2009
From: REMOVEmagicus23THIS at gmail.com (magicus)
Date: Tue, 28 Jul 2009 21:25:09 +0000 (UTC)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
	<200907281035.48713.hendrik@microcorp.co.za>
	<mailman.3844.1248793868.8015.python-list@python.org>
Message-ID: <h4nqbk$r8h$1@news.eternal-september.org>

On Tue, 28 Jul 2009 16:11:02 +0100, MRAB <python at mrabarnett.plus.com>
wrote:

> Hendrik van Rooyen wrote:
>> On Monday 27 July 2009 16:49:25 Aahz wrote:
>>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>>
>>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>>> I have searched, but I can find nothing about this mediocre language.
>>>>
>>>> Could you tell us more?
>>>>
>>> :-P
>>>
>>> (For anyone who is confused by Hendrik's humor, he is saying that
>>> David was referring to a programming language named "mediocre". 
>>> English grammar is confusing!)
>> 
>> This is true - I intended, when I started the post, to make a crack
>> about how he knew that he was mediocre - If there were some exam or
>> test that you have to pass or fail to be able to make the claim to
>> mediocrity. I was imagining a sort of devil's rating scale for
>> programmers, that could cause one to say things like:  "I am studying
>> hard so that I can get my mediocre certificate, and one day I hope to
>> reach hacker rank".
>> 
>> And then the similarity to "I am a COBOL programmer" struck me, and I
>> abandoned the ratings.
>> 
> If you were a "COBOL" programmer, would you want to shout about it? :-)

The last time I wrote anything in COBOL was sometime in the early 80s.
Somehow that makes me feel good, heh.

ciao,
f

-- 
?Using words to describe magic is like using a screwdriver to cut roast 
beef.?
-- Tom Robbins


From deets at nospam.web.de  Tue Jul 28 17:36:19 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 28 Jul 2009 23:36:19 +0200
Subject: C function taking double pointer to a structure variable as OUTPUT
	parameter
In-Reply-To: <mailman.3852.1248806955.8015.python-list@python.org>
References: <mailman.3852.1248806955.8015.python-list@python.org>
Message-ID: <7d99akF2at9g3U1@mid.uni-berlin.de>

fengmang_python at sina.com schrieb:
> Hi, Everyone,
> 
> I am a newbie to both Swig and Python. I am trying to export a set of C 
> APIs to Python.

If you are really dealing with a plain C-api, don't bother using SWIG - 
use ctypes. It comes with python >=2.5, is availabe as extra module for 
earlier versions, and makes wrapping C-libs a breeze.

Diez


From li.weidong at gmail.com  Tue Jul 28 17:41:30 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 14:41:30 -0700 (PDT)
Subject: Questions about unicodedata in python 2.6.2
References: <42274f5b-22a6-4449-9f8f-f4fd355c1aea@r25g2000vbn.googlegroups.com>
	<mailman.3837.1248790649.8015.python-list@python.org>
	<1d728013-fc77-469f-97bb-5769092377a7@p36g2000vbn.googlegroups.com>
	<mailman.3849.1248799068.8015.python-list@python.org>
Message-ID: <bd945ca4-f62a-47fa-92d5-d4a7047d4411@r24g2000vbn.googlegroups.com>

On Jul 28, 12:37?pm, Christian Heimes <li... at cheimes.de> wrote:
> 'make install' shouldn't compile any libraries if you run 'make' prior
> to 'make install'. I suggest you start again with a clean build tree of
> Python 2.6.2.
>
> Christian

You are perfectly right.  I started everything again after a "make
distclean".  This time I configured it as follows:

./configure --enable-unicode=ucs2 --enable-shared

to make things explicit, although I guess that the defaults would be
the same even when "--enable-unicode=ucs2 --enable-shared" are not
specified (in my case where ucs4 is not available).  The Makefile
generated then contains meaningful flags in RUNSHARED which was absent
before.

With this configuration, "make" was fine, except it "only" has the
following problems:

Failed to find the necessary bits to build these modules:
bsddb185           gdbm               sunaudiodev
To find the necessary bits, look in setup.py in detect_modules() for
the module's name.

That was not surprised because I did not have those available on my
machine.

The unicodedata.so was also created in the "make" process, and "make
install" showed no problem.

"make test" showed the following problems:

test_aepack
test_aepack skipped -- No module named aepack
test_al
test_al skipped -- No module named al
test_anydbm
Exception bsddb.db.DBRunRecoveryError: DBRunRecoveryError(-30974,
'DB_RUNRECOVERY: Fatal error, run database recovery -- PANIC: fatal
region error detected; run recovery') in  ignored

I guess this is caused by the missing bsddb185.  However, the problem
is, "make test" seemed to be hanging at that fatal error.

Do you know how critical are those failed tests?

Thanks for your help!

- Weidong


From deets at nospam.web.de  Tue Jul 28 17:45:45 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Tue, 28 Jul 2009 23:45:45 +0200
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <mailman.3856.1248812897.8015.python-list@python.org>
References: <mailman.3856.1248812897.8015.python-list@python.org>
Message-ID: <7d99s9F28m0aaU1@mid.uni-berlin.de>

Virgil Stokes schrieb:
> I would appreciate help on correcting a problem when trying to create an 
> *.exe file using py2exe via GUI2exe with Python 2.6.2.
> 
> When using GUI2exe to create an *.exe I always get the following warning 
> during the compile process:
> 
> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
> DeprecationWarning: the sets module is deprecated
> import sets
> 
> and this results in the creation of an *.exe file that can not be executed.
> 
> On the other hand, if I use the same procedure (on the same Python code) 
> with
> Python 2.5, there are no warnings and the *.exe works fine.
> 
> The procedure used is that given in the example "Less simpler one" at
> 
>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
> 
> Any suggestions, help, ... would be greatly appreciated.

If you don't need your app running on python2.3 and earlier, just remove 
the sets-module and replace it with the builtin "set".

Diez


From bakes at ymail.com  Tue Jul 28 17:59:26 2009
From: bakes at ymail.com (Bakes)
Date: Tue, 28 Jul 2009 14:59:26 -0700 (PDT)
Subject: FTP Offset larger than file.
References: <df8cad9d-c23d-4703-ba1c-d0d799bba659@32g2000yqj.googlegroups.com>
	<87ljm8vrcf.fsf@busola.homelinux.net>
	<bb5152f3-94ce-4bc7-bb96-444ff056c44c@g31g2000yqc.googlegroups.com>
	<fcf258b6-a09d-434c-ab2e-0423878b208f@y19g2000yqy.googlegroups.com> 
	<mailman.3848.1248799038.8015.python-list@python.org>
Message-ID: <6bf6294f-eb85-48b8-9b15-64fd20eb5989@32g2000yqj.googlegroups.com>

On Jul 28, 5:36?pm, Dave Angel <da... at ieee.org> wrote:
> Bakes wrote:
> > On 28 July, 15:18, Bakes <ba... at ymail.com> wrote:
>
> >> On 28 July, 15:01, Hrvoje Niksic <hnik... at xemacs.org> wrote:
>
> >>> Bakes <ba... at ymail.com> writes:
>
> >>>> The error I get is:
> >>>> ftplib.error_temp: 451-Restart offset 24576 is too large for file size
> >>>> 22852.
> >>>> 451 Restart offset reset to 0
> >>>> which tells me that the local file is larger than the external file,
> >>>> by about a kilobyte. Certainly, the local file is indeed that size, so
> >>>> my local script is doing the right things. I do wonder what is going
> >>>> wrong, can anyone enlighten me?
>
> >>> I'd say you failed to take buffering into account. ?You write into a
> >>> buffered file, yet you use os.path.getsize() to find out the current
> >>> file size. ?If the data is not yet flushed, you keep re-reading the same
> >>> stuff from the remote file, and writing it out. ?Once the buffer is
> >>> flushed, your file will contain more data than was retrieved from the
> >>> remote side, and eventually this will result in the error you see.
>
> >>> As a quick fix, you can add a file.flush() line after the
> >>> file.write(...) line, and the problem should go away.
>
> >> Thank you very much, that worked perfectly.
>
> > Actually, no it didn't. That fix works seamlessly in Linux, but gave
> > the same error in a Windows environment. Is that expected?
>
> This is a text file you're transferring. ?And you didn't specify "wb". ?
> So the Windows size will be larger than the Unix size, since you're
> expanding the newline characters.
>
> getsize() is looking at the size after newlines are expanded to 0d0a,
> while The remote file, presumably a Unix system likely has just has 0a.
>
> I think you'd do best just keeping track of the bytes you've written.
>
> DaveA

Thank you very much, that worked perfectly.


From jdgiotta at gmail.com  Tue Jul 28 18:15:35 2009
From: jdgiotta at gmail.com (John D Giotta)
Date: Tue, 28 Jul 2009 15:15:35 -0700 (PDT)
Subject: Semaphore Techniques
Message-ID: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>

I'm looking to run a process with a limit of 3 instances, but each
execution is over a crontab interval. I've been investigating the
threading module and using daemons to limit active thread objects, but
I'm not very successful at grasping the documentation.

Is it possible to do what I'm trying to do and if so anyone know of a
useful example to get started?


From python at mrabarnett.plus.com  Tue Jul 28 18:22:29 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Tue, 28 Jul 2009 23:22:29 +0100
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <h4nqbk$r8h$1@news.eternal-september.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<mailman.3765.1248685391.8015.python-list@python.org>	<h4kepl$qhf$1@panix3.panix.com>	<200907281035.48713.hendrik@microcorp.co.za>	<mailman.3844.1248793868.8015.python-list@python.org>
	<h4nqbk$r8h$1@news.eternal-september.org>
Message-ID: <4A6F7A25.3010004@mrabarnett.plus.com>

magicus wrote:
> On Tue, 28 Jul 2009 16:11:02 +0100, MRAB <python at mrabarnett.plus.com>
> wrote:
> 
>> Hendrik van Rooyen wrote:
>>> On Monday 27 July 2009 16:49:25 Aahz wrote:
>>>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>>>
>>>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>>>> I have searched, but I can find nothing about this mediocre language.
>>>>>
>>>>> Could you tell us more?
>>>>>
>>>> :-P
>>>>
>>>> (For anyone who is confused by Hendrik's humor, he is saying that
>>>> David was referring to a programming language named "mediocre". 
>>>> English grammar is confusing!)
>>> This is true - I intended, when I started the post, to make a crack
>>> about how he knew that he was mediocre - If there were some exam or
>>> test that you have to pass or fail to be able to make the claim to
>>> mediocrity. I was imagining a sort of devil's rating scale for
>>> programmers, that could cause one to say things like:  "I am studying
>>> hard so that I can get my mediocre certificate, and one day I hope to
>>> reach hacker rank".
>>>
>>> And then the similarity to "I am a COBOL programmer" struck me, and I
>>> abandoned the ratings.
>>>
>> If you were a "COBOL" programmer, would you want to shout about it? :-)
> 
> The last time I wrote anything in COBOL was sometime in the early 80s.
> Somehow that makes me feel good, heh.
> 
COBOL: it feels good when you stop. :-)

(I was actually referring to the convention of all capitals representing
shouting.)


From REMOVEmagicus23THIS at gmail.com  Tue Jul 28 18:26:28 2009
From: REMOVEmagicus23THIS at gmail.com (magicus)
Date: Tue, 28 Jul 2009 22:26:28 +0000 (UTC)
Subject: If Scheme is so good why MIT drops it?
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3765.1248685391.8015.python-list@python.org>
	<h4kepl$qhf$1@panix3.panix.com>
	<200907281035.48713.hendrik@microcorp.co.za>
	<mailman.3844.1248793868.8015.python-list@python.org>
	<h4nqbk$r8h$1@news.eternal-september.org>
	<mailman.3861.1248819752.8015.python-list@python.org>
Message-ID: <h4ntuk$s00$1@news.eternal-september.org>

On Tue, 28 Jul 2009 23:22:29 +0100, MRAB <python at mrabarnett.plus.com>
wrote:

> magicus wrote:
>> On Tue, 28 Jul 2009 16:11:02 +0100, MRAB <python at mrabarnett.plus.com>
>> wrote:
>> 
>>> Hendrik van Rooyen wrote:
>>>> On Monday 27 July 2009 16:49:25 Aahz wrote:
>>>>> In article <mailman.3765.1248685391.8015.python-list at python.org>,
>>>>>
>>>>> Hendrik van Rooyen  <hendrik at microcorp.co.za> wrote:
>>>>>> On Sunday 26 July 2009 21:26:46 David Robinow wrote:
>>>>>>>  I'm a mediocre programmer. Does this mean I should switch to PHP?
>>>>>> I have searched, but I can find nothing about this mediocre
>>>>>> language.
>>>>>>
>>>>>> Could you tell us more?
>>>>>>
>>>>> :-P
>>>>>
>>>>> (For anyone who is confused by Hendrik's humor, he is saying that
>>>>> David was referring to a programming language named "mediocre".
>>>>> English grammar is confusing!)
>>>> This is true - I intended, when I started the post, to make a crack
>>>> about how he knew that he was mediocre - If there were some exam or
>>>> test that you have to pass or fail to be able to make the claim to
>>>> mediocrity. I was imagining a sort of devil's rating scale for
>>>> programmers, that could cause one to say things like:  "I am studying
>>>> hard so that I can get my mediocre certificate, and one day I hope to
>>>> reach hacker rank".
>>>>
>>>> And then the similarity to "I am a COBOL programmer" struck me, and I
>>>> abandoned the ratings.
>>>>
>>> If you were a "COBOL" programmer, would you want to shout about it?
>>> :-)
>> 
>> The last time I wrote anything in COBOL was sometime in the early 80s.
>> Somehow that makes me feel good, heh.
>> 
> COBOL: it feels good when you stop. :-)
> 

It certainly does!

> (I was actually referring to the convention of all capitals representing
> shouting.)

I rarely shout and I thought that to this day it was still referred to as 
COBOL. I am still glad that I never pursued a career in dealing w/ such a 
language.

ciao,
f

-- 
"What you resist, persists."


From li.weidong at gmail.com  Tue Jul 28 18:31:05 2009
From: li.weidong at gmail.com (Weidong)
Date: Tue, 28 Jul 2009 15:31:05 -0700 (PDT)
Subject: Questions on python 2.6.2 installed files
Message-ID: <42bdecab-7b61-49d4-9d3b-52c14024c20f@r34g2000vba.googlegroups.com>

I would like to build a python 2.6.2 for Linux that runs on arm-based
embeded devices.  After some experiment of building from the python
2.6.2 source, I notice that the installed files from "make install"
are much too big for an embedded system.  For example, the files it
installs to /usr/local/lib/python2.6/ dir is over 350MB.

>From the following installed files,

/usr/local/bin/python
/usr/local/lib/libpython2.6.so.1.0

I do not see they have any "direct" dependency on the files installed
in /usr/local/lib/python2.6 dir.  What are the use of those files in /
usr/local/lib/python2.6?  What is the consequence if I do not put them
on the embedded system?

Is there a good way to directly make an installation "package" (or
tarball) of python 2.6.2 from the build result?

Any advice on configuration to make the results smaller will be
greatly appreciated!

- Weidong


From breamoreboy at yahoo.co.uk  Tue Jul 28 18:40:02 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Tue, 28 Jul 2009 23:40:02 +0100
Subject: New implementation of re module
In-Reply-To: <4A6DD6FB.8040609@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
Message-ID: <h4nuli$orm$1@ger.gmane.org>

MRAB wrote:
> Hi all,
> 
> I've been working on a new implementation of the re module. The details
> are at http://bugs.python.org/issue2636, specifically from
> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
> Python 2.6 on Windows if you want to try it out.
> 
> I'm interested in how fast it is generally, compared with the current re
> module, but especially when faced with those 'pathological' regular
> expressions which seem to take a long time to finish, for example:
> 
>     re.search(r"^(.+|D)*A$", "x" * 25 + "B")
> 
> which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs 
> with this new implementation.
I tried this on my 3GHz PC timings pretty much the same.

 From here http://bugs.python.org/issue1721518 I knocked up this.

import time
import re
import regex

s = "Add.1, 2020 and Add.1, 2021-2023, 2025, 2028 and 2029 and Add.1) R"
r = "(?:\s|,|and|Add\S*?|Parts?|\([^\)]*\)|[IV\-\d]+)*$"
t0 = time.clock()
print regex.search(r, s)
t1 = time.clock()
print "time", t1 - t0

print "It's going to crash"
t0 = time.clock()
print re.search(r, s)
t1 = time.clock()
print "It hasn't crashed time", t1 - t0

Output shows a slight change in timing:).

<_regex.RE_Match object at 0x0243A1A0>
time 0.00279001940191
It's going to crash
<_sre.SRE_Match object at 0x024396B0>
It hasn't crashed time 98.4238155967

> 
> TIA

I also got the files bm_regex_effbot.py and bm_regex_v8.py from
http://code.google.com/p/unladen-swallow/source/browse/#svn/tests/performance 
and ran them, then reran them having substituted regex for re.  Output 
timings were roughly effbot re 0.14secs, effbot regex 1.16secs, v8 re 
0.17secs and v8 regex 0.67secs.

HTH.

-- 
Kindest regards.

Mark Lawrence.



From steve at REMOVE-THIS-cybersource.com.au  Tue Jul 28 18:49:00 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 28 Jul 2009 22:49:00 GMT
Subject: "Deprecated sets module" with Python 2.6
References: <mailman.3856.1248812897.8015.python-list@python.org>
Message-ID: <027f7136$0$5185$c3e8da3@news.astraweb.com>

On Tue, 28 Jul 2009 22:28:09 +0200, Virgil Stokes wrote:

> When using GUI2exe to create an *.exe I always get the following warning
> during the compile process:
> 
>  C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>  DeprecationWarning: the sets module is deprecated 
>  import sets

The best solution would be to change every call to sets.Set() to set(), 
and change the line:

import sets

to this:

try:
    set
except NameError:
    from sets import Set as set


If you use sets.ImmutableSet, you will need to change that to frozenset 
in the same way.

This assumes you don't need to support older versions of Python, before 
set() became a built-in.



-- 
Steven



From thebiggestbangtheory at gmail.com  Tue Jul 28 19:12:19 2009
From: thebiggestbangtheory at gmail.com (nickname)
Date: Tue, 28 Jul 2009 16:12:19 -0700 (PDT)
Subject: Regular expression solution
Message-ID: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>

Hello all,
            I'm a newbie with python. I am looking to write a regex
program which can take in a piece of text and remove some parts of it
and supply the remaining parts back.

The input can be something like:
<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
" is  "+"21c";)</script>

The output should be something like
<script>document.write("hellooooo my name is  21c";)</script>

I have tried and failed. I am reading http://www.amk.ca/python/howto/regex/
and hope to get somewhere with this soon. If this is something simple,
can someone please help me out.

Thanks in advance for any help.




From contact at xavierho.com  Tue Jul 28 19:15:34 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 09:15:34 +1000
Subject: Extract images from PDF files
In-Reply-To: <bb3c4944-596f-478f-8c34-0478fbbbe9dd@q35g2000vbi.googlegroups.com>
References: <4de4e1e5-510d-43fe-a143-8b63413df923@w6g2000yqw.googlegroups.com>
	<mailman.3815.1248752499.8015.python-list@python.org>
	<bb3c4944-596f-478f-8c34-0478fbbbe9dd@q35g2000vbi.googlegroups.com>
Message-ID: <2d56febf0907281615g798087dcrb98b3b283befee71@mail.gmail.com>

I've got a non-Python solution if you have Acrobat 6 or up.

>From the menu, Advanced -> Document Processing -> Extract All Images...

If you need multiple PDFs done, Batch Processing would be a great start.

Then you can run another script to make the thumbnails, or use Photoshop.
Either way works!

Best regards,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/


On Wed, Jul 29, 2009 at 6:21 AM, writeson <doug.farrell at gmail.com> wrote:

> David,
>
> Thanks for your reply, I'll take a look at pdftohtml and see if it
> suits my needs.
>
> Thanks!
> Doug
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/3efb6e59/attachment-0001.html>

From lists at cheimes.de  Tue Jul 28 19:19:41 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 29 Jul 2009 01:19:41 +0200
Subject: Semaphore Techniques
In-Reply-To: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <4A6F878D.6010403@cheimes.de>

John D Giotta schrieb:
> I'm looking to run a process with a limit of 3 instances, but each
> execution is over a crontab interval. I've been investigating the
> threading module and using daemons to limit active thread objects, but
> I'm not very successful at grasping the documentation.
> 
> Is it possible to do what I'm trying to do and if so anyone know of a
> useful example to get started?

Since you are talking about crontab I assume that you are on an os that
supports pthreads. You problem can easily be solved with a named
semaphore (see sem_open(3) and sem_overview(7)). Unfortunately Python
doesn't expose named semaphores. The multiprocessing library uses named
semaphores but you can't set the name yourself.

You have to write your own C wrapper or search on pypi and through
Google. If you are going to write your own semaphore I highly recommend
Cython.

Christian


From philip at semanchuk.com  Tue Jul 28 19:26:53 2009
From: philip at semanchuk.com (Philip Semanchuk)
Date: Tue, 28 Jul 2009 19:26:53 -0400
Subject: Semaphore Techniques
In-Reply-To: <4A6F878D.6010403@cheimes.de>
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<4A6F878D.6010403@cheimes.de>
Message-ID: <D52D9110-35B7-4404-B1D4-BB6DE2E16A53@semanchuk.com>


On Jul 28, 2009, at 7:19 PM, Christian Heimes wrote:

> John D Giotta schrieb:
>> I'm looking to run a process with a limit of 3 instances, but each
>> execution is over a crontab interval. I've been investigating the
>> threading module and using daemons to limit active thread objects,  
>> but
>> I'm not very successful at grasping the documentation.
>>
>> Is it possible to do what I'm trying to do and if so anyone know of a
>> useful example to get started?
>
> Since you are talking about crontab I assume that you are on an os  
> that
> supports pthreads. You problem can easily be solved with a named
> semaphore (see sem_open(3) and sem_overview(7)). Unfortunately Python
> doesn't expose named semaphores. The multiprocessing library uses  
> named
> semaphores but you can't set the name yourself.
>
> You have to write your own C wrapper or search on pypi and through
> Google. If you are going to write your own semaphore I highly  
> recommend
> Cython.

My POSIX IPC extension permits manipulation of interprocess semaphores:
http://semanchuk.com/philip/posix_ipc/

There's also one for SysV IPC:
http://semanchuk.com/philip/sysv_ipc/

Enjoy
P



From db3l.net at gmail.com  Tue Jul 28 19:30:21 2009
From: db3l.net at gmail.com (David Bolen)
Date: Tue, 28 Jul 2009 19:30:21 -0400
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <m2bpn44c8i.fsf@valheru.db3l.homeip.net>

John D Giotta <jdgiotta at gmail.com> writes:

> I'm looking to run a process with a limit of 3 instances, but each
> execution is over a crontab interval. I've been investigating the
> threading module and using daemons to limit active thread objects, but
> I'm not very successful at grasping the documentation.
>
> Is it possible to do what I'm trying to do and if so anyone know of a
> useful example to get started?

Does it have to be built into the tool, or are you open to handling the
restriction right in the crontab entry?

For example, a crontab entry like:

  * * * * * test `pidof -x script.py | wc -w` -ge 4 || <path>/script.py

should attempt to run script.py every minute (adjust period as
required) unless there are already four of them running.  And if pidof
isn't precise enough you can put anything in there that would
accurately check your processes (grep a ps listing or whatever).

This works because if the test expression is true it returns 0 which
terminates the logical or (||) expression.

There may be some variations based on cron implementation (the above
was tested against Vixie cron), but some similar mechanism should be
available.

If you wanted to build it into the tool, it can be tricky in terms of
managing shared state (the count) amongst purely sibling/cooperative
processes.  It's much easier to ensure no overlap (1 instance), but
once you want 'n' instances you need an accurate process-wide counter.
I'm not positive, but don't think Python's built-in semaphores or
shared memory objects are cross-process.  (Maybe something in
multiprocessing in recent Python versions would work, though they may
need the sharing processes to all have been executed from a parent
script)

I do believe there are some third party interfaces (posix_ipc,
shm/shm_wrapper) that would provide access to posix shared-process
objects.  A semaphore may still not work as I'm not sure you can
obtain the current count.  But you could probably do something with
a shared memory counter in conjunction with a mutex of some sort, as
long as you were careful to clean it up on exit.

Or, you could stick PIDs into the shared memory and count PIDs on
a new startup (double checking against running processes to help
protect against process failures without cleanup).

You could also use the filesystem - have a shared directory where each
process dumps its PID, after first counting how many other PIDs are in
the directory and exiting if too many.

Of course all of these (even with a PID check) are risky in the
presence of unexpected failures.  It would be worse with something
like C code, but it should be reasonably easy to ensure that your
script has cleanup code even on an unexpected termination, and it's
not that likely the Python interpreter itself would crash.  Then
again, something external could kill the process.  Ensuring accuracy
and cleanup of shared state can be non-trivial.

You don't mention if you can support a single master daemon, but if
you could, then it can get a little easier as it can maintain and
protect access to the state - you could have each worker process
maintain a socket connection of some sort with the master daemon so it
could detect when they terminate for the count, and it could just
reject such connections from new processes if too many are running
already.  Of course, if the master daemon goes away then nobody would
run, which may or may not be an acceptable failure mode.

All in all, unless you need the scripts to enforce this behavior even
in the presence of arbitrary use, I'd just use an appropriate crontab
entry and move on to other problems :-)

-- David


From pavlovevidence at gmail.com  Tue Jul 28 19:36:49 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Tue, 28 Jul 2009 16:36:49 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>

On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
> I'm looking to run a process with a limit of 3 instances, but each
> execution is over a crontab interval. I've been investigating the
> threading module and using daemons to limit active thread objects, but
> I'm not very successful at grasping the documentation.
>
> Is it possible to do what I'm trying to do and if so anyone know of a
> useful example to get started?

It seems like you want to limit the number of processes to three; the
threading module won't help you there because it deals with threads
within a single process.

What I'd do is to simply run the system ps to see how many processes
are running (ps is pretty versatile on most systems and can find
specifically targeted processes like you program), and exit if there
are already three.

If you really are talking about multiple threads on a single server
process, then you want to use a thread pool (create three threads, and
give them tasks as necessary).  But you'll have to have a way for the
process started by crontab to communicate with the server.


Carl Banks


From zuo at chopin.edu.pl  Tue Jul 28 20:06:32 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Wed, 29 Jul 2009 02:06:32 +0200
Subject: need help using Tkinter
In-Reply-To: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
Message-ID: <op.uxsyk5owfvx12t@jerzozwiesz.home.aster.pl>

28-07-2009 o 17:17 Manzur Ahmed <dearmanzur at gmail.com> wrote:

> i wanted to ask you if one of you could help me to use Tkinter. i'm  
> trying
> to just create a simple GUI for which I have provided the code for below.
[snip]
> i tried to google search this and there were some threads that were  
> saying
> to install tcl but that does not work. I did check the Lib directory  
> under
> the Python directory and I did not see a Tkinter module anywhere which I
> think is the problem. Do you know how I would go about with getting this
> module and if that is not the problem or if you think it might be caused  
> by
> something else, can you please give me some guidance?

What operating system do you use?

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From sjmachin at lexicon.net  Tue Jul 28 20:26:40 2009
From: sjmachin at lexicon.net (John Machin)
Date: Tue, 28 Jul 2009 17:26:40 -0700 (PDT)
Subject: xlrd - insert column?
References: <75fb7538-5079-4c99-83b7-cf3afa1e222c@c29g2000yqd.googlegroups.com>
Message-ID: <c6be7377-cfe4-4a93-b602-d448d0bfe5a7@g1g2000pra.googlegroups.com>

On Jul 29, 6:05?am, LeeRisq <leer... at gmail.com> wrote:
> Does xlrd have the capability to insert a column?

No. If there was anything in the PyPI description, the README, or the
docs that gave you the faintest hope that xlrd does anything other
than read Excel files, please raise a documentation bug-fix request.

Start here: http://www.python-excel.org and read the tutorial.

Cheers,

John


From nobody at nowhere.com  Tue Jul 28 20:45:08 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 01:45:08 +0100
Subject: bad certificate error
References: <mailman.3835.1248788885.8015.python-list@python.org>
	<332a5bba-48d5-4c8b-9c1e-288790d85dbb@o32g2000yqm.googlegroups.com>
	<m263dca8ze.fsf@cs.uu.nl>
Message-ID: <pan.2009.07.29.00.45.07.953000@nowhere.com>

On Tue, 28 Jul 2009 21:44:05 +0200, Piet van Oostrum wrote:

>>j> 		# cert_file is a PEM formatted certificate chain file.
>>j> 		connection = httplib.HTTPSConnection(host, int(port), key_file,
>>j> cert_file)
> 
> What happens if you set cert_file to None? This would indicate that you
> are not interested in the server's certificate.
> 
> By the way, is the cert_file you supply the certificate of the CA that
> signed the server's cert (in contrast to yours)?

The cert_file parameter is the client certificate. You must provide
either both key_file and cert_file, or neither.



From nobody at nowhere.com  Tue Jul 28 20:54:23 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 01:54:23 +0100
Subject: Regular expression solution
References: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>
Message-ID: <pan.2009.07.29.00.54.23.125000@nowhere.com>

On Tue, 28 Jul 2009 16:12:19 -0700, nickname wrote:

>             I'm a newbie with python. I am looking to write a regex
> program which can take in a piece of text and remove some parts of it
> and supply the remaining parts back.
> 
> The input can be something like:
> <script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
> " is  "+"21c";)</script>
> 
> The output should be something like
> <script>document.write("hellooooo my name is  21c";)</script>

import re
r = re.compile(r'"\s*\+\s*"')
s = r'''<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
" is  "+"21c";)</script>'''
r.sub('', s)



From python at mrabarnett.plus.com  Tue Jul 28 20:58:50 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 01:58:50 +0100
Subject: New implementation of re module
In-Reply-To: <4a6f5a0f$0$25500$426a74cc@news.free.fr>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<mailman.3792.1248722883.8015.python-list@python.org>	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>	<mailman.3850.1248801945.8015.python-list@python.org>
	<4a6f5a0f$0$25500$426a74cc@news.free.fr>
Message-ID: <4A6F9ECA.3010205@mrabarnett.plus.com>

William Dode wrote:
> On 28-07-2009, MRAB wrote:
> 
>> With the official Python 2.6 distribution for Mac OS X it works.
>> The source code is intended to replace the current 're' module in Python
>> 2.7 (and I'll be porting it to Python 3.2), so I'm not that worried
>> about Python versions earlier than 2.6 for testing, although if there's
>> sufficient need then I could tweak the sources for 2.5.
> 
> I understand now why i could'nt compile it !
> 
> So, i would like if it's not too much work for you.
> 
There's a new version which should compile with Python 2.5 now.


From cocobear.cn at gmail.com  Tue Jul 28 21:20:29 2009
From: cocobear.cn at gmail.com (cocobear)
Date: Tue, 28 Jul 2009 18:20:29 -0700 (PDT)
Subject: merge two png pic
Message-ID: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>

This two png file has their own palette

>>> im1.mode
'P'
>>> im.mode
'P'
>>> im.getpalette == im1.getpalette
False

I can use this code to merge two png pic together:

Map = Image.new("RGB", (x,y))
Map.paste(im, box)
Map.paste(im1,box)

Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)

But if the two png pic is too big , or if I have to merge more pic
together, I will get MemoryError:

>>> Image.new("RGB",(44544,38656))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
new
    return Image()._new(core.fill(mode, size, color))
MemoryError

How can I directly merge two pic to a ?P' mode png with palette.



From contact at xavierho.com  Tue Jul 28 21:29:15 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 11:29:15 +1000
Subject: merge two png pic
In-Reply-To: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
Message-ID: <2d56febf0907281829x4d43a1abse2c271ad857174c1@mail.gmail.com>

On Wed, Jul 29, 2009 at 11:20 AM, cocobear <cocobear.cn at gmail.com> wrote:

>
> >>> Image.new("RGB",(44544,38656))
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
> new
>    return Image()._new(core.fill(mode, size, color))
> MemoryError


a 44544x38656 pixel PNG file? I don't mean to be nosy, but what is this for,
if you could share?


> How can I directly merge two pic to a ?P' mode png with palette.


Save to disk incrementally is one way I can think of. It's a lot slower, but
definitely more space than your RAM.

Good luck,

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/4519095d/attachment-0001.html>

From icebergwtf at gmail.com  Tue Jul 28 23:11:28 2009
From: icebergwtf at gmail.com (tiefeng wu)
Date: Wed, 29 Jul 2009 11:11:28 +0800
Subject: Regular expression solution
In-Reply-To: <pan.2009.07.29.00.54.23.125000@nowhere.com>
References: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>
	<pan.2009.07.29.00.54.23.125000@nowhere.com>
Message-ID: <4314c1f70907282011g799ccbf2tf44a4d4dd95dc8a7@mail.gmail.com>

2009/7/29 Nobody <nobody at nowhere.com>:
>> The output should be something like
>> <script>document.write("hellooooo my name is ?21c";)</script>
>
> import re
> r = re.compile(r'"\s*\+\s*"')
> s = r'''<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+
> " is ?"+"21c";)</script>'''
> r.sub('', s)
>

Nobody's solution is good.
here is more complicated solution, just for regex practice :-)

>>> s = '<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+" n"+"ame"+" is  "+"21c";)</script>'
>>> new_s = re.sub(r'(?<=")(.+)(?=")', ''.join(re.findall(r'"([^"]+)"', s)), s)
>>> new_s
'<script>document.write("hellooooo my name is  21c";)</script>'


From Brian.Mingus at colorado.edu  Tue Jul 28 23:42:31 2009
From: Brian.Mingus at colorado.edu (Brian)
Date: Tue, 28 Jul 2009 21:42:31 -0600
Subject: Regular expression solution
In-Reply-To: <4314c1f70907282011g799ccbf2tf44a4d4dd95dc8a7@mail.gmail.com>
References: <df753d49-937f-4e92-b72e-2299dbbbf8c5@e27g2000yqm.googlegroups.com>
	<pan.2009.07.29.00.54.23.125000@nowhere.com>
	<4314c1f70907282011g799ccbf2tf44a4d4dd95dc8a7@mail.gmail.com>
Message-ID: <9839a05c0907282042w778caa87je53b3d34e4b00049@mail.gmail.com>

On Tue, Jul 28, 2009 at 9:11 PM, tiefeng wu <icebergwtf at gmail.com> wrote:

> 2009/7/29 Nobody <nobody at nowhere.com>:
> >> The output should be something like
> >> <script>document.write("hellooooo my name is  21c";)</script>
> >
> > import re
> > r = re.compile(r'"\s*\+\s*"')
> > s = r'''<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+"
> n"+"ame"+
> > " is  "+"21c";)</script>'''
> > r.sub('', s)
> >
>
> Nobody's solution is good.
> here is more complicated solution, just for regex practice :-)
>
> >>> s = '<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+"
> n"+"ame"+" is  "+"21c";)</script>'
> >>> new_s = re.sub(r'(?<=")(.+)(?=")', ''.join(re.findall(r'"([^"]+)"',
> s)), s)
> >>> new_s
> '<script>document.write("hellooooo my name is  21c";)</script>'
> --
> http://mail.python.org/mailman/listinfo/python-list
>

 >>> from time import time>>> import re>>>
s='<script>document.write("h" +"e"+ "ll"+ "ooooo"+ " m" +"y"+"
n"+"ame"+" is  "+"21c";)</script>'>>> *# my version*>>>
start=time();null=s.replace(' +','+').replace('+
','+').replace('+','').replace('"','').replace('(','("').replace(';)','";)');*print*
time()-start2.8133392334e-05>>> *# nobody's version*>>> r =
re.compile(r'"\s*\+\s*"')>>> start = time();r.sub('',s);*print*
time()-start3.40938568115e-05>>> *# tiefeng's version*>>>
start=time();re.sub(r'(?<=")(.+)(?=")',
''.join(re.findall(r'"([^"]+)"', s)), s);*print*
time()-start0.000455141067505>>>
3.40938568115e-05/2.8133392334e-051.2118644067781548>>>
0.000455141067505/2.8133392334e-0516.177966101690096>>>
0.000455141067505/3.40938568115e-0513.349650349662966
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090728/6e464d39/attachment-0001.html>

From darkneter at gmail.com  Tue Jul 28 23:58:53 2009
From: darkneter at gmail.com (NighterNet)
Date: Tue, 28 Jul 2009 20:58:53 -0700 (PDT)
Subject: simple splash screen?
Message-ID: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>

I am trying to make a simple splash screen from python 3.1.Not sure
where to start looking for it. Can any one help?


From hjtoi-better-remove-before-reply at comcast.net  Wed Jul 29 00:16:38 2009
From: hjtoi-better-remove-before-reply at comcast.net (Heikki Toivonen)
Date: Tue, 28 Jul 2009 21:16:38 -0700
Subject: M2Crypto hangs on this URL
References: <4a6de1ef$0$1612$742ec2ed@news.sonic.net>
Message-ID: <h4oif8$5ck$1@aioe.org>

John Nagle wrote:
> There's something strange about this URL:
> 
> "https://sagar310.pontins.com/sraep/"

The following program finishes fine for me using M2Crypto 0.20beta1 +
openssl 0.9.8g. Like Martin mentioned in another message, maybe someone
fixed the site.

from M2Crypto import SSL
ctx = SSL.Context()
# If you comment out the next 2 lines, the connection won't be secure
#ctx.set_verify(SSL.verify_peer | SSL.verify_fail_if_no_peer_cert, depth=9)
#if ctx.load_verify_locations('ca.pem') != 1: raise Exception('No CA certs')
c = SSL.Connection(ctx)
c.connect(('sagar310.pontins.com', 443))
c.send('GET /sraep/ \n')
c.close()

-- 
  Heikki Toivonen - http://heikkitoivonen.net


From dearmanzur at gmail.com  Wed Jul 29 00:35:44 2009
From: dearmanzur at gmail.com (Manzur Ahmed)
Date: Wed, 29 Jul 2009 00:35:44 -0400
Subject: need help using Tkinter
In-Reply-To: <op.uxsyk5owfvx12t@jerzozwiesz.home.aster.pl>
References: <60972b200907280817q208e8117we76cde8f66fdf999@mail.gmail.com>
	<op.uxsyk5owfvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <60972b200907282135s7fd125b4h5dc118a60027ff64@mail.gmail.com>

i figured it out.  its actually because i'm using python 3.1.  for python
3.0+, many of the packages are lowercased, tkinter being one of them and so
thats why i wan getting a module not found error . . .  thanks for getting
back to me.

manzur

On Tue, Jul 28, 2009 at 8:06 PM, Jan Kaliszewski <zuo at chopin.edu.pl> wrote:

> 28-07-2009 o 17:17 Manzur Ahmed <dearmanzur at gmail.com> wrote:
>
> i wanted to ask you if one of you could help me to use Tkinter. i'm trying
>> to just create a simple GUI for which I have provided the code for below.
>>
> [snip]
>
>> i tried to google search this and there were some threads that were saying
>> to install tcl but that does not work. I did check the Lib directory under
>> the Python directory and I did not see a Tkinter module anywhere which I
>> think is the problem. Do you know how I would go about with getting this
>> module and if that is not the problem or if you think it might be caused
>> by
>> something else, can you please give me some guidance?
>>
>
> What operating system do you use?
>
> *j
>
> --
> Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/36b5a563/attachment-0001.html>

From gagsl-py2 at yahoo.com.ar  Wed Jul 29 02:08:19 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 29 Jul 2009 03:08:19 -0300
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com>
	<mailman.3812.1248748204.8015.python-list@python.org>
	<027ed9be$0$5185$c3e8da3@news.astraweb.com>
Message-ID: <op.uxtfb500x6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 09:02:40 -0300, Steven D'Aprano  
<steve at remove-this-cybersource.com.au> escribi?:
> On Mon, 27 Jul 2009 23:16:39 -0300, Gabriel Genellina wrote:
>
>> I don't see the point on "fixing" either the Python script or httplib to
>> accomodate for an invalid server certificate... If it's just for
>> internal testing, I'd use HTTP instead (at least until the certificate
>> is fixed).
>
> In real life, sometimes you need to drive with bad brakes on your car,
> walk down dark alleys in the bad part of town, climb a tree without a
> safety line, and use a hammer without wearing goggles. We can do all
> these things.
>
> The OP has said that, for whatever reason, he needs to ignore a bad
> server certificate when connecting to HTTPS. Python is a language where
> developers are allowed to shoot themselves in the foot, so long as they
> do so in full knowledge of what they're doing.
>
> So, putting aside all the millions of reasons why the OP shouldn't accept
> an invalid certificate, how can he accept an invalid certificate?

Yes, I understand the situation, but I'm afraid there is no way (that I  
know of). At least not without patching _ssl.c; all the SSL negotiation is  
handled by the OpenSSL library itself.

I vaguely remember a pure Python SSL implementation somewhere that perhaps  
could be hacked to bypass all controls. But making it work properly will  
probably require a lot more effort than installing a self signed  
certificate in the server...

-- 
Gabriel Genellina



From jayshree06comp at gmail.com  Wed Jul 29 02:58:36 2009
From: jayshree06comp at gmail.com (jayshree)
Date: Tue, 28 Jul 2009 23:58:36 -0700 (PDT)
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
	<cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>
	<7d5brmF2a1alcU1@mid.uni-berlin.de>
Message-ID: <2b5b00b8-f9ba-4d16-b950-681aa6fa010a@24g2000yqm.googlegroups.com>

On Jul 27, 2:55?pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> jayshree wrote:
> > On Jul 27, 1:09?pm, Kushal Kumaran <kushal.kumaran+pyt... at gmail.com>
> > wrote:
> >> On Mon, Jul 27, 2009 at 12:58 PM, jayshree<jayshree06c... at gmail.com>
> >> wrote:
> >> > pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
>
> >> > Please tell me how to open a file placed in any directory or in same
> >> > directory.
>
> >> > After opening this file i want to use the contain (public key ) for
> >> > encryption
>
> >> Does the code you've put into your message not read that file? ?If you
> >> get an exception, copy-paste in the traceback message you get into
> >> your mail.
>
> >> --
> >> kushal
>
> > ? ? try:
> > ? ? ? ? pk = open('/home/jayshree/my_key.public.pem' , 'rb').read()
> > ? ? except IOError:
> > ? ? ? ? print "Error: can\'t find file or read data"
> > ? ? else:
> > ? ? ? ? print "reading from file successfully"
>
> >>Still no error it gives .what to do?
>
> Erm - so it doesn't give an error - which means you have successfully opened
> a file, and read it's contents.
>
> So what exactly is your problem?
>
> Diez- Hide quoted text -
>
> - Show quoted text -

> The Exact Problem is how to use the key containing by .pem file for 'encryption' .
>can i print the contents of the .pem file

see http://stackoverflow.com/questions/1176864/problem-with-the-pem-file


From gagsl-py2 at yahoo.com.ar  Wed Jul 29 02:58:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Wed, 29 Jul 2009 03:58:39 -0300
Subject: "Deprecated sets module" with Python 2.6
References: <4A6F5F59.4080507@it.uu.se>
Message-ID: <op.uxthn1wdx6zn5v@lepton.softlabbsas.com.ar>

En Tue, 28 Jul 2009 17:28:09 -0300, Virgil Stokes <vs at it.uu.se> escribi?:

> I would appreciate help on correcting a problem when trying to create an  
> *.exe file using py2exe via GUI2exe with Python 2.6.2.
>
> When using GUI2exe to create an *.exe I always get the following warning  
> during the compile process:
>
>  C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>  DeprecationWarning: the sets module is deprecated
>  import sets

Note that build_exe.py is part of the py2exe package - the warning says  
that py2exe itself is importing a deprecated module, it's not in your code.

> and this results in the creation of an *.exe file that can not be  
> executed.

I don't think the warning above is related to your problem. Are you using  
the latest py2exe version?
You may get more help in the py2exe mailing list; see  
http://www.py2exe.org/

-- 
Gabriel Genellina



From huangchonggnu at gmail.com  Wed Jul 29 03:29:35 2009
From: huangchonggnu at gmail.com (hch)
Date: Wed, 29 Jul 2009 15:29:35 +0800
Subject: No subject
Message-ID: <cb49ae490907290029l4cfa5365o35e038aff9f79cfd@mail.gmail.com>

Hi, everyone

Is there a python script can get a list of how much stack space each
function in your program uses? ( the program is compiled by gcc)

Any advice will be appreciate.


From vs at it.uu.se  Wed Jul 29 03:46:50 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Wed, 29 Jul 2009 09:46:50 +0200
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <7d99s9F28m0aaU1@mid.uni-berlin.de>
References: <mailman.3856.1248812897.8015.python-list@python.org>
	<7d99s9F28m0aaU1@mid.uni-berlin.de>
Message-ID: <4A6FFE6A.8060503@it.uu.se>

Diez B. Roggisch wrote:
> Virgil Stokes schrieb:
>> I would appreciate help on correcting a problem when trying to create 
>> an *.exe file using py2exe via GUI2exe with Python 2.6.2.
>>
>> When using GUI2exe to create an *.exe I always get the following 
>> warning during the compile process:
>>
>> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>> DeprecationWarning: the sets module is deprecated
>> import sets
>>
>> and this results in the creation of an *.exe file that can not be 
>> executed.
>>
>> On the other hand, if I use the same procedure (on the same Python 
>> code) with
>> Python 2.5, there are no warnings and the *.exe works fine.
>>
>> The procedure used is that given in the example "Less simpler one" at
>>
>>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
>>
>> Any suggestions, help, ... would be greatly appreciated.
>
> If you don't need your app running on python2.3 and earlier, just 
> remove the sets-module and replace it with the builtin "set".
Of course Diez, this is a good suggestion. However, in this case the 
Python code that I am trying to convert into an *.exe file does not 
refer to sets directly; i.e, the use of this module is buried within a 
package that is imported (wxPython) which is not under my control.

--V
>
> Diez




From huangchonggnu at gmail.com  Wed Jul 29 03:51:26 2009
From: huangchonggnu at gmail.com (hch)
Date: Wed, 29 Jul 2009 15:51:26 +0800
Subject: about analyze object's stack usage
Message-ID: <cb49ae490907290051gd1678a7yc8d82dd29c53a367@mail.gmail.com>

Hi, everyone

Is there a python script can get a list of how much stack space each
function in your program uses? ( the program is compiled by gcc)

Any advice will be appreciate.


From vs at it.uu.se  Wed Jul 29 03:52:57 2009
From: vs at it.uu.se (Virgil Stokes)
Date: Wed, 29 Jul 2009 09:52:57 +0200
Subject: "Deprecated sets module" with Python 2.6
In-Reply-To: <4A6FFE6A.8060503@it.uu.se>
References: <mailman.3856.1248812897.8015.python-list@python.org>	<7d99s9F28m0aaU1@mid.uni-berlin.de>
	<4A6FFE6A.8060503@it.uu.se>
Message-ID: <4A6FFFD9.4050508@it.uu.se>

Virgil Stokes wrote:
> Diez B. Roggisch wrote:
>> Virgil Stokes schrieb:
>>> I would appreciate help on correcting a problem when trying to 
>>> create an *.exe file using py2exe via GUI2exe with Python 2.6.2.
>>>
>>> When using GUI2exe to create an *.exe I always get the following 
>>> warning during the compile process:
>>>
>>> C:\Python26\lib\site-packages\py2exe\build_exe.py:16:
>>> DeprecationWarning: the sets module is deprecated
>>> import sets
>>>
>>> and this results in the creation of an *.exe file that can not be 
>>> executed.
>>>
>>> On the other hand, if I use the same procedure (on the same Python 
>>> code) with
>>> Python 2.5, there are no warnings and the *.exe works fine.
>>>
>>> The procedure used is that given in the example "Less simpler one" at
>>>
>>>  http://code.google.com/p/gui2exe/wiki/GUI2ExeExamplesin
>>>
>>> Any suggestions, help, ... would be greatly appreciated.
>>
>> If you don't need your app running on python2.3 and earlier, just 
>> remove the sets-module and replace it with the builtin "set".
> Of course Diez, this is a good suggestion. However, in this case the 
> Python code that I am trying to convert into an *.exe file does not 
> refer to sets directly; i.e, the use of this module is buried within a 
> package that is imported (wxPython) which is not under my control.
>
> --V
>>
>> Diez
>
>
Whoops, the reference to the module sets is in py2exe not wxPython.

--V



From hendrik at microcorp.co.za  Wed Jul 29 04:08:24 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Wed, 29 Jul 2009 10:08:24 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <4A6F1506.9030207@mrabarnett.plus.com>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<200907281035.48713.hendrik@microcorp.co.za>
	<4A6F1506.9030207@mrabarnett.plus.com>
Message-ID: <200907291008.24572.hendrik@microcorp.co.za>

On Tuesday 28 July 2009 17:11:02 MRAB wrote:

> If you were a "COBOL" programmer, would you want to shout about it? :-)

Hey don't knock it! - at the time, it was either COBOL or FORTRAN
or some assembler or coding in hex or octal.

And if code is data, where is Pythons ALTER statement?

*Ducks*

:-)    Hendrik






From milesck at umich.edu  Wed Jul 29 04:14:03 2009
From: milesck at umich.edu (Miles Kaufmann)
Date: Wed, 29 Jul 2009 01:14:03 -0700
Subject: python 3 and stringio.seek
In-Reply-To: <h4mui9$q1o$1@nnrp-beta.newsland.it>
References: <h4mui9$q1o$1@nnrp-beta.newsland.it>
Message-ID: <ECDBC5EB-B60D-4F54-81A8-9989C33AA70C@umich.edu>


On Jul 28, 2009, at 6:30 AM, Michele Petrazzo wrote:

> Hi list,
> I'm trying to port a my library to python 3, but I have a problem  
> with a
> the stringio.seek:
> the method not accept anymore a value like pos=-6 mode=1, but the  
> "old"
> (2.X) version yes...
>
> The error:
>  File "/home/devel/Py3/lib/python3.0/io.py", line 2031, in seek
>    return self._seek(pos, whence)
> IOError: Can't do nonzero cur-relative seeks
>
>
> How solve this?

In Python 2, StringIO is a stream of bytes (non-Unicode characters).   
In Python 3, StringIO is a stream of text (Unicode characters).  In  
the early development of Python 3 (and 3.1's _pyio), it was  
implemented as a TextIOWrapper over a BytesIO buffer.  TextIOWrapper  
does not support relative seeks because it is difficult to map the  
concept of a "current position" between bytes and the text that it  
encodes, especially with variable-width encodings and other  
considerations.  Furthermore, the value returned from  
TextIOWrapper.tell isn't just a file position but a "cookie" that  
contains other data necessary to restore the decoding mechanism to the  
same state.  However, for the default encoding (utf-8), the current  
position is equivalent to that of the underlying bytes buffer.

In Python 3, StringIO is implemented using an internal buffer of  
Unicode characters.  There is no technical reason why it can't support  
relative seeks; I assume it does not for compatibility with the  
original Python TextIOWrapper implementation (which is present in  
3.1's _pyio, but not in 3.0).

Note that because of the different implementations, StringIO.tell()  
(and seek) behaves differently for the C and Python implementations:

$ python3.1
 >>> import io, _pyio
 >>> s = io.StringIO('\u263A'); s.read(1), s.tell()
('?', 1)
 >>> s = _pyio.StringIO('\u263A'); s.read(1), s.tell()
('?', 3)

The end result seems to be that, for text streams (including  
StreamIO), you *should* treat the value returned by tell() as an  
opaque magic cookie, and *only* pass values to seek() that you have  
obtained from a previous tell() call.  However, in practice, it  
appears that you *may* seek StringIO objects relatively by characters  
using s.seek(s.tell() + n), so long as you do not use the  
_pyio.StringIO implementation.

If what you actually want is a stream of bytes, use BytesIO, which may  
be seeked (sought?) however you please.

I'm basing this all on my reading of the Python source (and svn  
history), since it doesn't seem to be documented, so take it with a  
grain of salt.

-Miles



From gregor.thalhammer at gmail.com  Wed Jul 29 04:14:31 2009
From: gregor.thalhammer at gmail.com (gregorth)
Date: Wed, 29 Jul 2009 01:14:31 -0700 (PDT)
Subject: fast video encoding
Message-ID: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>

Hi all,

for a scientific application I need to save a video stream to disc for
further post processing. My cam can deliver 8bit grayscale images with
resolution 640x480 with a framerate up to 100Hz, this is a data rate
of 30MB/s. Writing the data uncompressed to disc hits the data
transfer limits of my current system and creates huge files. Therefore
I would like to use video compression, preferably fast and high
quality to lossless encoding. Final file size is not that important.
Because of the hardware I am bound to WinXP.

I already tried pymedia for encoding to mpeg2, however I only managed
to get a framerate of about 30-40fps (on a 1.8GHz dual core). There is
still room for improvements in my code, but before trying hard I want
to ask for advices or other possibilities. I also found gstreamer with
pygst python bindings, which seems to be more modern (and performant?)
package than pymedia. I did not yet try it, especially since I didn't
find a simple code example of how to use it for my use case. Can
somebody give me a hint?

I also found huffyuv or lagarith which is provided as a directshow
codec for Windows. Can somebody give me a hint how to use a directshow
codec with python?

I am a novice with video encoding. I found that few codecs support
gray scale images. Any hints to take advantage of the fact that I only
have gray scale images?

Thanks for any help

Gregor



From __peter__ at web.de  Wed Jul 29 04:21:05 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 29 Jul 2009 10:21:05 +0200
Subject: instead of depending on data = array('h') .. write samples 1 by 1
	to w = wave.open("wav.wav", "w")
References: <mailman.3855.1248811181.8015.python-list@python.org>
Message-ID: <h4p0p8$l9k$01$1@news.t-online.com>

'2+ wrote:

> it says
> Wave_write.writeframes(data)
> will that mean
> "from array import array"
> is a must?
> 
> this does the job:
> 
> import oil
> import wave
> from array import array
> 
> a = oil.Sa()
> 
> w = wave.open("current.wav", "w")
> w.setnchannels(2)
> w.setsampwidth(2)
> w.setframerate(44100)
> 
> data = array('h')
> 
> for gas in range(44100 * 5):
>     a.breath()
>     r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>     l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>     data.append(r)
>     data.append(l)
> 
> w.writeframes(data.tostring())
> w.close()
> 
> don't like array becoming so huge so tested this and it was also okay:
> 
> for gas in range(44100 * 5):
>     a.breath()
>     data = array('h')
>     r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>     l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>     data.append(r)
>     data.append(l)
>     w.writeframes(data.tostring())
> 
> but without array .. it becomes 15secs(3 times longer than was
> intended to be) of wav file:
> 
> for gas in range(44100 * 5):
>     a.breath()
>     r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>     l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>     w.writeframes(hex(r))
>     w.writeframes(hex(l))

Doesn't it sound strange, too? You are writing bogus bytes to the file. 
Compare:
 
>>> import array
>>> array.array("h", [42]).tostring()
'*\x00'
>>> hex(42)
'0x2a'

Not only do they differ in length, the contents are different, too. If 
you're unfamiliar with string escape codes, here's a way to see the bytes:

>>> map(ord, array.array("h", [42]).tostring())
[42, 0]
>>> map(ord, hex(42))
[48, 120, 50, 97]

> should i just be happy with depennding on using array?
> or is there a solution to make the last one work properly?

There is a way to make the last one work: use struct.pack("h", r) instead of 
hex(r). I'm of course assuming that the first version does give you the 
desired result. You should not continue before you have verified that.

I still recommend array for performance reasons. If memory usage is an issue 
you can adopt a hybrid approach:

# untested
from itertools import islice
from array import array

def gen_data():
    for gas in xrange(44100 * 5): # range --> xrange
        a.breath()
        r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
        l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
        yield r
        yield l

data = gen_data()
N = 2**20
while True:
    chunk = array('h')
    chunk.extend(islice(data, N))
    if not chunk:
        break
    w.writeframes(chunk.tostring())

This will limit the array size to 4N bytes.

Peter



From michael at stroeder.com  Wed Jul 29 04:45:05 2009
From: michael at stroeder.com (=?ISO-8859-1?Q?Michael_Str=F6der?=)
Date: Wed, 29 Jul 2009 10:45:05 +0200
Subject: 64-bit issues with dictionaries in Python 2.6
Message-ID: <hpe5k6-ed5.ln1@nb2.stroeder.com>

HI!

Are there any known issues with dictionaries in Python 2.6 (not 2.6.2)
when running on a 64-bit platform?

A friend of mine experiences various strange problems with my web2ldap
running with Python 2.6 shipped with openSUSE 11.1 x64. For me it seems
some dictionary-based internal registries of web2ldap are not working.
Yes, the next test would be to compile Python 2.6.2 from source...

Any hint is appreciated.

Ciao, Michael.


From user at example.net  Wed Jul 29 05:02:25 2009
From: user at example.net (superpollo)
Date: Wed, 29 Jul 2009 11:02:25 +0200
Subject: idiom for list looping
Message-ID: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>

hi clp.

i want to get from here:

nomi = ["one", "two", "three"]

to here:

0 - one
1 - two
2 - three

i found two ways:

first way:

for i in range(len(nomi)):
     print i, "-", nomi[i]

or second way:

for (i, e) in enumerate(nomi):
     print i, "-", e

which one is "better"? is there a more pythonic way to do it?

bye

ps:

max2 at 192.168.1.102:~/test$ python -V
Python 2.3.4
max2 at 192.168.1.102:~/test$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
max2 at 192.168.1.102:~/test$


From d at vidr.cc  Wed Jul 29 05:31:47 2009
From: d at vidr.cc (David Roberts)
Date: Wed, 29 Jul 2009 19:31:47 +1000
Subject: idiom for list looping
In-Reply-To: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
Message-ID: <fe0877110907290231u33c567c9kf13210a544af1282@mail.gmail.com>

To the best of my knowledge the second way is more pythonic - the
first is a little too reminiscent of C. A couple of notes:
- you don't need the parentheses around "i, e"
- if you were going to use the first way it's better to use xrange
instead of range for iteration

--
David Roberts
http://da.vidr.cc/



On Wed, Jul 29, 2009 at 19:02, superpollo<user at example.net> wrote:
> hi clp.
>
> i want to get from here:
>
> nomi = ["one", "two", "three"]
>
> to here:
>
> 0 - one
> 1 - two
> 2 - three
>
> i found two ways:
>
> first way:
>
> for i in range(len(nomi)):
> ? ?print i, "-", nomi[i]
>
> or second way:
>
> for (i, e) in enumerate(nomi):
> ? ?print i, "-", e
>
> which one is "better"? is there a more pythonic way to do it?
>
> bye
>
> ps:
>
> max2 at 192.168.1.102:~/test$ python -V
> Python 2.3.4
> max2 at 192.168.1.102:~/test$ uname -a
> Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
> max2 at 192.168.1.102:~/test$
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From python at mrabarnett.plus.com  Wed Jul 29 05:38:29 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 10:38:29 +0100
Subject: idiom for list looping
In-Reply-To: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
Message-ID: <4A701895.5000003@mrabarnett.plus.com>

superpollo wrote:
> hi clp.
> 
> i want to get from here:
> 
> nomi = ["one", "two", "three"]
> 
> to here:
> 
> 0 - one
> 1 - two
> 2 - three
> 
> i found two ways:
> 
> first way:
> 
> for i in range(len(nomi)):
>     print i, "-", nomi[i]
> 
> or second way:
> 
> for (i, e) in enumerate(nomi):
>     print i, "-", e
> 
> which one is "better"? is there a more pythonic way to do it?
> 
'enumerate' is the Pythonic solution.


From gnewsg at gmail.com  Wed Jul 29 06:25:19 2009
From: gnewsg at gmail.com (Giampaolo Rodola')
Date: Wed, 29 Jul 2009 03:25:19 -0700 (PDT)
Subject: "Deprecated sets module" with Python 2.6
References: <4A6F5F59.4080507@it.uu.se>
	<mailman.3874.1248850703.8015.python-list@python.org>
Message-ID: <d16dc2eb-e18e-4906-833a-e42806bc28f4@c1g2000yqi.googlegroups.com>

What about this?

import warnings
warnings.simplefilter('ignore', DeprecationWarning)
import the_module_causing_the_warning
warnings.resetwarnings()


--- Giampaolo
http://code.google.com/p/pyftpdlib
http://code.google.com/p/psutil


From contact at xavierho.com  Wed Jul 29 06:37:44 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 20:37:44 +1000
Subject: idiom for list looping
In-Reply-To: <4A701895.5000003@mrabarnett.plus.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
Message-ID: <2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>

>
> superpollo wrote:
>
>>
>> for (i, e) in enumerate(nomi):
>>    print i, "-", e
>>
>> Just to be random:

print '\n'.join(["%s - %s" % (i, e) for i, e in enumerate(nomi)])

This has one advantage: only print once. So it's slightly faster if you have
a list of a large amount.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/aa3e26bb/attachment-0001.html>

From python at mrabarnett.plus.com  Wed Jul 29 06:52:08 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 11:52:08 +0100
Subject: idiom for list looping
In-Reply-To: <2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
Message-ID: <4A7029D8.3010700@mrabarnett.plus.com>

Xavier Ho wrote:
>     superpollo wrote:
> 
> 
>         for (i, e) in enumerate(nomi):
>            print i, "-", e
> 
> Just to be random:
> 
> print '\n'.join(["%s - %s" % (i, e) for i, e in enumerate(nomi)])
> 
> This has one advantage: only print once. So it's slightly faster if you 
> have a list of a large amount.
> 
Slightly shorter:

print '\n'.join("%s - %s" % p for p in enumerate(nomi))

:-)


From contact at xavierho.com  Wed Jul 29 07:00:37 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 21:00:37 +1000
Subject: idiom for list looping
In-Reply-To: <4A7029D8.3010700@mrabarnett.plus.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<4A7029D8.3010700@mrabarnett.plus.com>
Message-ID: <2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>

On Wed, Jul 29, 2009 at 8:52 PM, MRAB <python at mrabarnett.plus.com> wrote:

> Slightly shorter:
>
> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
>
> :-)
>
That's cool. Does that make the "list" a tuple? (not that it matters, I'm
just curious!)

I just tested for a list of 1000 elements (number in letters from 1 to 1000
code I wrote for doing project euler problem 17), and the join method is 0.1
seconds faster than the for loop! Woo!? ;p
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/41513f45/attachment-0001.html>

From user at example.net  Wed Jul 29 07:02:14 2009
From: user at example.net (superpollo)
Date: Wed, 29 Jul 2009 13:02:14 +0200
Subject: idiom for list looping
In-Reply-To: <mailman.3884.1248864728.8015.python-list@python.org>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>	<4A701895.5000003@mrabarnett.plus.com>	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<mailman.3884.1248864728.8015.python-list@python.org>
Message-ID: <4a702c37$0$34617$4fafbaef@reader4.news.tin.it>

MRAB wrote:
> Xavier Ho wrote:
> 
>>     superpollo wrote:
>>
>>
>>         for (i, e) in enumerate(nomi):
>>            print i, "-", e
>>
>> Just to be random:
>>
>> print '\n'.join(["%s - %s" % (i, e) for i, e in enumerate(nomi)])
>>
>> This has one advantage: only print once. So it's slightly faster if 
>> you have a list of a large amount.
>>
> Slightly shorter:
> 
> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
> 
> :-)

 >>> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
   File "<stdin>", line 1
     print '\n'.join("%s - %s" % p for p in enumerate(nomi))
                                     ^
SyntaxError: invalid syntax
 >>> print '\n'.join(["%s - %s" % p for p in enumerate(nomi)])
0 - one
1 - two
2 - three
 >>> help()

Welcome to Python 2.3!  This is the online help utility.
...
 >>>

;-)

bye


From contact at xavierho.com  Wed Jul 29 07:16:41 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 21:16:41 +1000
Subject: idiom for list looping
In-Reply-To: <2d56febf0907290416x75d2edb3i88ad452ba18894f1@mail.gmail.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<mailman.3884.1248864728.8015.python-list@python.org>
	<4a702c37$0$34617$4fafbaef@reader4.news.tin.it>
	<2d56febf0907290416x75d2edb3i88ad452ba18894f1@mail.gmail.com>
Message-ID: <2d56febf0907290416x389a1b72w64f583d1d229bbf9@mail.gmail.com>

Ack, sent to the wrong email again.

On Wed, Jul 29, 2009 at 9:02 PM, superpollo <user at example.net> wrote:

>
> >>> print '\n'.join("%s - %s" % p for p in enumerate(nomi))
>  File "<stdin>", line 1
>    print '\n'.join("%s - %s" % p for p in enumerate(nomi))
>                                    ^
> SyntaxError: invalid syntax


lol, I knew I shouldn't have trusted untested code!


> >>> print '\n'.join(["%s - %s" % p for p in enumerate(nomi)])
> 0 - one
> 1 - two
> 2 - three
>

Yup.. but using a variable for the tuple itself was a good move though =P.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/d828df45/attachment-0001.html>

From python at mrabarnett.plus.com  Wed Jul 29 07:17:14 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 12:17:14 +0100
Subject: idiom for list looping
In-Reply-To: <2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>	<4A701895.5000003@mrabarnett.plus.com>	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>	<4A7029D8.3010700@mrabarnett.plus.com>
	<2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>
Message-ID: <4A702FBA.8060303@mrabarnett.plus.com>

Xavier Ho wrote:
> On Wed, Jul 29, 2009 at 8:52 PM, MRAB <python at mrabarnett.plus.com 
> <mailto:python at mrabarnett.plus.com>> wrote:
> 
>     Slightly shorter:
> 
>     print '\n'.join("%s - %s" % p for p in enumerate(nomi))
> 
>     :-)
> 
> That's cool. Does that make the "list" a tuple? (not that it matters, 
> I'm just curious!)
> 
I've just replaced the list comprehension with a generator expression.



From contact at xavierho.com  Wed Jul 29 07:20:50 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 21:20:50 +1000
Subject: idiom for list looping
In-Reply-To: <4A702FBA.8060303@mrabarnett.plus.com>
References: <4a701022$0$34623$4fafbaef@reader4.news.tin.it>
	<4A701895.5000003@mrabarnett.plus.com>
	<2d56febf0907290337j688607bfhb0f171f5a982abfd@mail.gmail.com>
	<4A7029D8.3010700@mrabarnett.plus.com>
	<2d56febf0907290400s5f31b8bcs549df9cdaa72bc28@mail.gmail.com>
	<4A702FBA.8060303@mrabarnett.plus.com>
Message-ID: <2d56febf0907290420m7543ee8bs3c6ad9914fb51d39@mail.gmail.com>

On Wed, Jul 29, 2009 at 9:17 PM, MRAB <python at mrabarnett.plus.com> wrote:


> I've just replaced the list comprehension with a generator expression.
>
>
Oh, and that isn't in Python 2.3.... I see. Generators are slightly newer,
eh.

Thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/59b37fb2/attachment-0001.html>

From nick at craig-wood.com  Wed Jul 29 07:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Wed, 29 Jul 2009 06:29:56 -0500
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
Message-ID: <slrnh70a5q.d1m.nick@irishsea.home.craig-wood.com>

John D Giotta <jdgiotta at gmail.com> wrote:
>  I'm looking to run a process with a limit of 3 instances, but each
>  execution is over a crontab interval. I've been investigating the
>  threading module and using daemons to limit active thread objects, but
>  I'm not very successful at grasping the documentation.
> 
>  Is it possible to do what I'm trying to do and if so anyone know of a
>  useful example to get started?

If you want a simple, cross platform way of doing it, then bind each
process to a different local tcp port.

Make a list of 3 ports, and try binding to each port in turn.  If you
can't find a port to bind to then there are already 3 instances
running.

Something like this

import socket
PORTS = range(10000,10003)
lock_sock = None

def lock_process(_locks = []):
    for port in PORTS:
        sock = socket.socket()
        try:
            sock.bind(("localhost", port))
        except socket.error, e:
            sock = None
        else:
            _locks.append(sock)
            break
    else:
        raise Exception("Too many instances of me running")

for i in range(5):
    print "Trying",i+1
    lock_process()


Which prints

Trying 1
Trying 2
Trying 3
Trying 4
Traceback (most recent call last):
  File "<stdin>", line 20, in <module>
  File "<stdin>", line 16, in lock_process
Exception: Too many instances of me running

You could do the same thing with lock files also very easily...


-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From spookyk at gmail.com  Wed Jul 29 07:35:42 2009
From: spookyk at gmail.com (Rincewind)
Date: Wed, 29 Jul 2009 04:35:42 -0700 (PDT)
Subject: QFileDialog setFileMode blues
Message-ID: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>

Heya,

I am fairly new to Python and even newer to Qt.
The problem is opening a Qt file dialog to select folders only.
QFileDialog has a nice and dandy setFileMode() function just for that.
The only trouble is that I cannot make it work.
Last thing I've tried was something like this:

        self.fd = QtGui.QFileDialog()
        self.fd.setFileMode(self.fd.FileMode(4))
        filename = self.fd.getOpenFileName()

..but it was fruitless.

Any help? Tons of internets in return!


From Ron.Barak at lsi.com  Wed Jul 29 07:36:05 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Wed, 29 Jul 2009 12:36:05 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <mailman.44.1248861603.12188.python-list@python.org>
References: <mailman.44.1248861603.12188.python-list@python.org>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>


Hi,

I wanted to make a python byte-code file executable, expecting to be able to run it without specifying "python" on the (Linux bash) command line.

So, I wrote the following:

[root at VMLinux1 python]# cat test_pyc.py
#!/usr/bin/env python

print "hello"
[root at VMLinux1 python]#

and made its pyc file executable:

[root at VMLinux1 python]# ls -ls test_pyc.pyc
4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
[root at VMLinux1 python]#

So, I see:

[root at VMLinux1 python]# file test_pyc.py*
test_pyc.py:  a python script text executable
test_pyc.pyc: python 2.3 byte-compiled
[root at VMLinux1 python]#

If I try to do the following, no problem:

[root at VMLinux1 python]# python test_pyc.pyc
hello
[root at VMLinux1 python]#

However, the following fails:

[root at VMLinux1 python]# ./test_pyc.pyc
-bash: ./test_pyc.pyc: cannot execute binary file
[root at VMLinux1 python]#

Is there a way to run a pyc file without specifying the python path ?

Bye,
Ron.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/a6d3b02a/attachment-0001.html>

From phil at riverbankcomputing.com  Wed Jul 29 07:45:03 2009
From: phil at riverbankcomputing.com (Phil Thompson)
Date: Wed, 29 Jul 2009 12:45:03 +0100
Subject: QFileDialog setFileMode blues
In-Reply-To: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>
References: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>
Message-ID: <8477fc1d11b68f7e3e11237d957890b1@localhost>

On Wed, 29 Jul 2009 04:35:42 -0700 (PDT), Rincewind <spookyk at gmail.com>
wrote:
> Heya,
> 
> I am fairly new to Python and even newer to Qt.
> The problem is opening a Qt file dialog to select folders only.
> QFileDialog has a nice and dandy setFileMode() function just for that.
> The only trouble is that I cannot make it work.
> Last thing I've tried was something like this:
> 
>         self.fd = QtGui.QFileDialog()
>         self.fd.setFileMode(self.fd.FileMode(4))
>         filename = self.fd.getOpenFileName()
> 
> ..but it was fruitless.
> 
> Any help? Tons of internets in return!

QFileDialog.getOpenFileName() is a static method that creates its own
QFileDialog internally. It's not using the one you have created and
configured.

Phil


From marcusw at cox.net  Wed Jul 29 08:23:14 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 08:23:14 -0400
Subject: fast video encoding
In-Reply-To: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
References: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
Message-ID: <h4pevi$1bqt$1@adenine.netfront.net>

On 7/29/2009 4:14 AM, gregorth wrote:
> Hi all,
> 
> for a scientific application I need to save a video stream to disc for
> further post processing. My cam can deliver 8bit grayscale images with
> resolution 640x480 with a framerate up to 100Hz, this is a data rate
> of 30MB/s. Writing the data uncompressed to disc hits the data
> transfer limits of my current system and creates huge files. Therefore
> I would like to use video compression, preferably fast and high
> quality to lossless encoding. Final file size is not that important.
Try googling realtime greyscale video codec...
> Because of the hardware I am bound to WinXP.
There's always a way to run linux :p
> 
> I already tried pymedia for encoding to mpeg2, however I only managed
> to get a framerate of about 30-40fps (on a 1.8GHz dual core). There is
> still room for improvements in my code, but before trying hard I want
> to ask for advices or other possibilities. I also found gstreamer with
> pygst python bindings, which seems to be more modern (and performant?)
> package than pymedia. I did not yet try it, especially since I didn't
> find a simple code example of how to use it for my use case. Can
> somebody give me a hint?
Video encoding is not my specialty, but my recommendation here is to 
drop python because of its slow speed and work in c as much as possible.
> 
> I also found huffyuv or lagarith which is provided as a directshow
> codec for Windows. Can somebody give me a hint how to use a directshow
> codec with python?
Not me, sorry :(
Never worked directly with directshow (no pun intended).
> 
> I am a novice with video encoding. I found that few codecs support
> gray scale images. Any hints to take advantage of the fact that I only
> have gray scale images?
Greyscale PNG or BMP compression.
> 
> Thanks for any help
Don't know if this counts as help, but you're welcome!
> 
> Gregor
> 
Marcus


From marcusw at cox.net  Wed Jul 29 08:24:33 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 08:24:33 -0400
Subject: simple splash screen?
In-Reply-To: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
Message-ID: <h4pf23$1bqt$2@adenine.netfront.net>

On 7/28/2009 11:58 PM, NighterNet wrote:
> I am trying to make a simple splash screen from python 3.1.Not sure
> where to start looking for it. Can any one help?
Trying to make a splash screen for python?
Or trying to do image processing in python?

Marcus


From sibtey.mehndi at genpact.com  Wed Jul 29 08:25:22 2009
From: sibtey.mehndi at genpact.com (Mehndi, Sibtey)
Date: Wed, 29 Jul 2009 05:25:22 -0700
Subject: how to embed the python interpreter into web App
Message-ID: <1A343A98C8DAE44A8D9D1BF310F90D5E023D54C3@GCPWINGGN2EVS11.IND.CORP.AD>

Hi All
I am trying to embed the python interpreter in to a web app but could not get the way, any one can suggest me how to do this.

Thanks,
Sibtey Mehdi


This e-mail (and any attachments), is confidential and may be privileged. It may be read, copied and used only
by intended recipients. Unauthorized access to this e-mail (or attachments) and disclosure or copying of its 
contents or any action taken in reliance on it is unlawful. Unintended recipients must notify the sender immediately 
by e-mail/phone & delete it from their system without making any copies or disclosing it to a third person.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/ed6d98b5/attachment-0001.html>

From duncan.booth at invalid.invalid  Wed Jul 29 08:26:11 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 29 Jul 2009 12:26:11 GMT
Subject: Need help in passing a "-c command" argument to the interactive
	shell.
References: <230bcf11-2227-4d7f-9048-862c1bdb1912@13g2000prl.googlegroups.com>
Message-ID: <Xns9C5788AE7C466duncanbooth@127.0.0.1>

Bill <bsagert at gmail.com> wrote:

> On my windows box I type => c:\x>python -c "import re"
> 
> The result is => c:\x>
> 
> In other words, the Python interactive shell doesn't even open. What
> am I doing wrong?
> 
> I did RTFM at http://www.python.org/doc/1.5.2p2/tut/node4.html on
> argument passing, but to no avail.

Why are you reading documentation for Python 1.5? There have been just a 
few releases since then.

Try reading http://docs.python.org/using/cmdline.html instead, specifically 
the part about the -i command line option. Or you could just try "python 
-?" at a command prompt.

-- 
Duncan Booth http://kupuguy.blogspot.com


From marcusw at cox.net  Wed Jul 29 08:34:09 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 08:34:09 -0400
Subject: about analyze object's stack usage
In-Reply-To: <mailman.3877.1248853887.8015.python-list@python.org>
References: <mailman.3877.1248853887.8015.python-list@python.org>
Message-ID: <h4pfke$1bqt$3@adenine.netfront.net>

On 7/29/2009 3:51 AM, hch wrote:
> Is there a python script can get a list of how much stack space each
> function in your program uses?
I don't think so.
You could try raw reading of the memory from another thread using ctypes
and pointers, but that would be madness.
> ( the program is compiled by gcc)
If you're talking about a c program, almost certainly not. What you 
should do is just use gdb and disas each function and look at what it 
subtracts off of %esp at the third instruction in the function.
I can explain it to you if you are not very experienced in gdb and 
assembly...

Marcus


From rashidsdpk at gmail.com  Wed Jul 29 08:54:24 2009
From: rashidsdpk at gmail.com (Rashid Ali Soomro)
Date: Wed, 29 Jul 2009 05:54:24 -0700 (PDT)
Subject: Particle research opens door for new technology
Message-ID: <ff376d57-0e81-40cc-866f-ef1b74b10f31@o15g2000yqm.googlegroups.com>

Big uses for small particles will be explored at the annual Particle
Technology Research Centre Conference at The University of Western
Ontario July 9 and 10.more http://0nanotechnology0.blogspot.com/


From catalinfest at gmail.com  Wed Jul 29 09:03:06 2009
From: catalinfest at gmail.com (catalinfest at gmail.com)
Date: Wed, 29 Jul 2009 06:03:06 -0700 (PDT)
Subject: Help with sql and python
Message-ID: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>

Hello !

I have accont on myphpadmin on my server.
I want to create one script in python.
This script manage sql task from my sql server .
How i make this in a simple way ?

Thank you !


From contact at xavierho.com  Wed Jul 29 09:08:12 2009
From: contact at xavierho.com (Xavier Ho)
Date: Wed, 29 Jul 2009 23:08:12 +1000
Subject: Particle research opens door for new technology
In-Reply-To: <ff376d57-0e81-40cc-866f-ef1b74b10f31@o15g2000yqm.googlegroups.com>
References: <ff376d57-0e81-40cc-866f-ef1b74b10f31@o15g2000yqm.googlegroups.com>
Message-ID: <2d56febf0907290608v4fe62d32n804e43008713572b@mail.gmail.com>

Is this a spam? Why did you have to send it 4 times, and it's already in the
past (July 9 and 10) ?

Ching-Yun "Xavier" Ho, Technical Artist

Contact Information
Mobile: (+61) 04 3335 4748
Skype ID: SpaXe85
Email: contact at xavierho.com
Website: http://xavierho.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/53e3e5e3/attachment-0001.html>

From v1d4l0k4 at gmail.com  Wed Jul 29 09:10:47 2009
From: v1d4l0k4 at gmail.com (v1d4l0k4)
Date: Wed, 29 Jul 2009 13:10:47 +0000
Subject: Working with platform.system()
Message-ID: <9a5b5be90907290610t1868ef07p20a5c2bdc3404ab8@mail.gmail.com>

Hi!

I want to know how I can get different expected return values by
platform.system() method. I want to sniff some systems (Linux, Windows, Mac,
BSD, Solaris) and I don't know how I can check them correctly. Could you
give me some expected return values that you know?

Thanks in advance,
Paulo Ricardo
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/5616da8c/attachment-0001.html>

From james at agentultra.com  Wed Jul 29 09:29:55 2009
From: james at agentultra.com (J Kenneth King)
Date: Wed, 29 Jul 2009 09:29:55 -0400
Subject: escaping characters in filenames
Message-ID: <854osv7h2k.fsf@agentultra.com>


I wrote a script to process some files using another program.  One thing
I noticed was that both os.listdir() and os.path.walk() will return
unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
module or recipe that escapes file names and was wondering if anyone
could point me in the right direction.

As an aside, the script is using subprocess.call() with the "shell=True"
parameter.  There isn't really a reason for doing it this way (was just
the fastest way to write it and get a prototype working).  I was
wondering if Popen objects were sensitive to unescaped names like the
shell.  I intend to refactor the function to use Popen objects at some
point and thought perhaps escaping file names may not be entirely
necessary.

Cheers


From nospam at nospam.com  Wed Jul 29 09:55:32 2009
From: nospam at nospam.com (Gilles Ganault)
Date: Wed, 29 Jul 2009 15:55:32 +0200
Subject: Compiling Python for uCLinux appliance?
Message-ID: <7sk075l5p7eq8mek9ooqj5kr0ds10hrvfq@4ax.com>

Hello

I just got a small appliance based on a Blackfin CPU with 64MB RAM and
258MB NAND flash. Using the stock software, there's about 30MB of RAM
left.

Besides C/C++ and shel scripts, I was wondering if it were realistic
to upload a few Python scripts in such a small appliance?

Thank you.


From piet at cs.uu.nl  Wed Jul 29 10:14:45 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 29 Jul 2009 16:14:45 +0200
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
Message-ID: <m2fxcfefu2.fsf@cs.uu.nl>

>>>>> Carl Banks <pavlovevidence at gmail.com> (CB) wrote:

>CB> On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
>>> I'm looking to run a process with a limit of 3 instances, but each
>>> execution is over a crontab interval. I've been investigating the
>>> threading module and using daemons to limit active thread objects, but
>>> I'm not very successful at grasping the documentation.
>>> 
>>> Is it possible to do what I'm trying to do and if so anyone know of a
>>> useful example to get started?

>CB> It seems like you want to limit the number of processes to three; the
>CB> threading module won't help you there because it deals with threads
>CB> within a single process.

>CB> What I'd do is to simply run the system ps to see how many processes
>CB> are running (ps is pretty versatile on most systems and can find
>CB> specifically targeted processes like you program), and exit if there
>CB> are already three.

That will surely run into some race conditions. If the limit of 3
processes is soft then that wouldn't be a big deal, however.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From spookyk at gmail.com  Wed Jul 29 10:15:53 2009
From: spookyk at gmail.com (Rincewind)
Date: Wed, 29 Jul 2009 07:15:53 -0700 (PDT)
Subject: QFileDialog setFileMode blues
References: <13e9a34a-d92a-49f0-96da-3abc17b0f280@c14g2000yqm.googlegroups.com>
	<mailman.3889.1248867908.8015.python-list@python.org>
Message-ID: <cce08084-37db-4099-bac1-f76f2a7e6e3b@k1g2000yqf.googlegroups.com>

On Jul 29, 12:45 pm, Phil Thompson <p... at riverbankcomputing.com>
wrote:
> On Wed, 29 Jul 2009 04:35:42 -0700 (PDT), Rincewind <spoo... at gmail.com>
> wrote:
>
> > Heya,
>
> > I am fairly new to Python and even newer to Qt.
> > The problem is opening a Qt file dialog to select folders only.
> > QFileDialog has a nice and dandy setFileMode() function just for that.
> > The only trouble is that I cannot make it work.
> > Last thing I've tried was something like this:
>
> >         self.fd = QtGui.QFileDialog()
> >         self.fd.setFileMode(self.fd.FileMode(4))
> >         filename = self.fd.getOpenFileName()
>
> > ..but it was fruitless.
>
> > Any help? Tons of internets in return!
>
> QFileDialog.getOpenFileName() is a static method that creates its own
> QFileDialog internally. It's not using the one you have created and
> configured.
>
> Phil

You are awesome, thanks!


From python at mrabarnett.plus.com  Wed Jul 29 10:22:34 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 15:22:34 +0100
Subject: escaping characters in filenames
In-Reply-To: <854osv7h2k.fsf@agentultra.com>
References: <854osv7h2k.fsf@agentultra.com>
Message-ID: <4A705B2A.2050807@mrabarnett.plus.com>

J Kenneth King wrote:
> I wrote a script to process some files using another program.  One thing
> I noticed was that both os.listdir() and os.path.walk() will return
> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
> module or recipe that escapes file names and was wondering if anyone
> could point me in the right direction.
> 
That's only necessary if you're building a command line and passing it
as a string.

> As an aside, the script is using subprocess.call() with the "shell=True"
> parameter.  There isn't really a reason for doing it this way (was just
> the fastest way to write it and get a prototype working).  I was
> wondering if Popen objects were sensitive to unescaped names like the
> shell.  I intend to refactor the function to use Popen objects at some
> point and thought perhaps escaping file names may not be entirely
> necessary.
> 
Pass the command line to Popen as a list of strings.


From deets at nospam.web.de  Wed Jul 29 10:46:47 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 29 Jul 2009 16:46:47 +0200
Subject: Compiling Python for uCLinux appliance?
References: <7sk075l5p7eq8mek9ooqj5kr0ds10hrvfq@4ax.com>
Message-ID: <7db5mnF2bf9i2U1@mid.uni-berlin.de>

Gilles Ganault wrote:

> Hello
> 
> I just got a small appliance based on a Blackfin CPU with 64MB RAM and
> 258MB NAND flash. Using the stock software, there's about 30MB of RAM
> left.
> 
> Besides C/C++ and shel scripts, I was wondering if it were realistic
> to upload a few Python scripts in such a small appliance?

Try & check out the gumstix software repo. It comes with python, and thus
some crosscompiling/build-instructions should be in there.

Diez


From jakecjacobson at gmail.com  Wed Jul 29 11:07:34 2009
From: jakecjacobson at gmail.com (jakecjacobson)
Date: Wed, 29 Jul 2009 08:07:34 -0700 (PDT)
Subject: bad certificate error
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
	<mailman.3790.1248719042.8015.python-list@python.org>
	<027e226c$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3812.1248748204.8015.python-list@python.org>
	<027ed9be$0$5185$c3e8da3@news.astraweb.com> 
	<mailman.3873.1248847683.8015.python-list@python.org>
Message-ID: <fdefad35-b9fe-46c8-8e48-51275e0d9236@h11g2000yqb.googlegroups.com>

On Jul 29, 2:08?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Tue, 28 Jul 2009 09:02:40 -0300, Steven D'Aprano ?
> <st... at remove-this-cybersource.com.au> escribi?:
>
>
>
> > On Mon, 27 Jul 2009 23:16:39 -0300, Gabriel Genellina wrote:
>
> >> I don't see the point on "fixing" either the Python script or httplib to
> >> accomodate for an invalid server certificate... If it's just for
> >> internal testing, I'd use HTTP instead (at least until the certificate
> >> is fixed).
>
> > In real life, sometimes you need to drive with bad brakes on your car,
> > walk down dark alleys in the bad part of town, climb a tree without a
> > safety line, and use a hammer without wearing goggles. We can do all
> > these things.
>
> > The OP has said that, for whatever reason, he needs to ignore a bad
> > server certificate when connecting to HTTPS. Python is a language where
> > developers are allowed to shoot themselves in the foot, so long as they
> > do so in full knowledge of what they're doing.
>
> > So, putting aside all the millions of reasons why the OP shouldn't accept
> > an invalid certificate, how can he accept an invalid certificate?
>
> Yes, I understand the situation, but I'm afraid there is no way (that I ?
> know of). At least not without patching _ssl.c; all the SSL negotiation is ?
> handled by the OpenSSL library itself.
>
> I vaguely remember a pure Python SSL implementation somewhere that perhaps ?
> could be hacked to bypass all controls. But making it work properly will ?
> probably require a lot more effort than installing a self signed ?
> certificate in the server...
>
> --
> Gabriel Genellina

I have it working and I want to thank everyone for their efforts and
very helpful hints.  The error was with me and not understanding the
documentation about the cert_file & key_file.  After using openssl to
divide up my p12 file into a cert file and a key file using the
instructions http://security.ncsa.uiuc.edu/research/grid-howtos/usefulopenssl.php.
I got everything working.

Again, much thanks.

Jake


From darkneter at gmail.com  Wed Jul 29 11:20:45 2009
From: darkneter at gmail.com (NighterNet)
Date: Wed, 29 Jul 2009 08:20:45 -0700 (PDT)
Subject: simple splash screen?
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
	<h4pf23$1bqt$2@adenine.netfront.net>
Message-ID: <68539c2a-e2f6-4956-b779-17d21ca422b1@2g2000prl.googlegroups.com>

On Jul 29, 5:24?am, Marcus Wanner <marc... at cox.net> wrote:
> On 7/28/2009 11:58 PM, NighterNet wrote:> I am trying to make a simple splash screen from python 3.1.Not sure
> > where to start looking for it. Can any one help?
>
> Trying to make a splash screen for python?
> Or trying to do image processing in python?
>
> Marcus

trying to use jpg,gif,png for the splash screen


From wwn1 at sfu.ca  Wed Jul 29 11:24:25 2009
From: wwn1 at sfu.ca (WilsonOfCanada)
Date: Wed, 29 Jul 2009 08:24:25 -0700 (PDT)
Subject: Clearing an array
Message-ID: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>

Hellos,

I was wondering if there is any built-in function that clears the
array.  I was also wondering if this works:

arrMoo = ['33', '342', .... '342']
arrMoo = []


From tutufan at gmail.com  Wed Jul 29 11:24:52 2009
From: tutufan at gmail.com (Mike)
Date: Wed, 29 Jul 2009 08:24:52 -0700 (PDT)
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com>

On Jul 27, 11:34?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> I've been working on a new implementation of the re module.

Fabulous!

If you're extending/changing the interface, there are a couple of sore
points in the current implementation I'd love to see addressed:

- findall/finditer doesn't find overlapping matches.  Sometimes you
really *do* want to know all possible matches, even if they overlap.
This comes up in bioinformatics, for example.

- split won't split on empty patterns, e.g. empty lookahead patterns.
This means that it can't be used for a whole class of interesting
cases.  This has been discussed previously:

    http://bugs.python.org/issue3262
    http://bugs.python.org/issue852532
    http://bugs.python.org/issue988761

- It'd be nice to have a version of split that generates the parts
(one by one) rather than returning the whole list.

- Repeated subgroup match information is not available.  That is, for
a match like this

    re.match('(.){3}', 'xyz')

there's no way to discover that the subgroup first matched 'x', then
matched 'y', and finally matched 'z'.  Here is one past proposal
(mine), perhaps over-complex, to address this problem:

    http://mail.python.org/pipermail/python-dev/2004-August/047238.html

Mike



From Omer.Khalid at cern.ch  Wed Jul 29 11:26:55 2009
From: Omer.Khalid at cern.ch (Omer Khalid)
Date: Wed, 29 Jul 2009 17:26:55 +0200
Subject: Very Strange Problem
Message-ID: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>

Hi,

I am having a very strange problem with modifying a variable in a list in my
program. Here is the code:

# a list that contains dictionary objects
jobs = []

index=5
for each in range(index):
         jobs.append({'v':0})

some_function(index):
       if jobs[index]['v'] == 0:
                   # set it to 1
                   jobs[index]['v'] = 1
                   print "Set to 1"
      else:
                   print "Already set to 1"

loop():
        index=0
        for each in range(len(jobs)):
                 some_function(index)
                 index +=1


Apparently, the jobs[index]['v'] never get updated in the some_function but
the print statement afterwards get printed...

What's really surprising is that there are no errors or exceptions and my my
program runs in a single thread...so i have been unable to explain this
behavior.

Any insight would be much appreciated!

Cheers
Omer
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/56133f08/attachment-0001.html>

From deets at nospam.web.de  Wed Jul 29 11:32:36 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 29 Jul 2009 17:32:36 +0200
Subject: Clearing an array
References: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>
Message-ID: <7db8ckF28m03sU1@mid.uni-berlin.de>

WilsonOfCanada wrote:

> Hellos,
> 
> I was wondering if there is any built-in function that clears the
> array.  I was also wondering if this works:
> 
> arrMoo = ['33', '342', .... '342']
> arrMoo = []

Most of the time, yes. Unless you have something like this, then it won't
work:


foo = [10]

bar = foo # an alias

foo = []

assert foo == bar

Then what you need to to is this:

foo[:] = []


Diez


From tack at urandom.ca  Wed Jul 29 11:39:00 2009
From: tack at urandom.ca (Jason Tackaberry)
Date: Wed, 29 Jul 2009 11:39:00 -0400
Subject: Clearing an array
In-Reply-To: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>
References: <fd79dba5-3297-4d22-bb26-2276b8d20cbc@u38g2000pro.googlegroups.com>
Message-ID: <1248881940.7696.28.camel@willow>

On Wed, 2009-07-29 at 08:24 -0700, WilsonOfCanada wrote:
> I was wondering if there is any built-in function that clears the
> array.

The proper python term would be "list."  You can remove all elements of
a list 'l' like so:

   del l[:]


>   I was also wondering if this works:
> 
> arrMoo = ['33', '342', .... '342']
> arrMoo = []

That doesn't clear the list as such, but rather creates a new list, and
reassigns the new list to the 'arrMoo' name in the local scope.
Consider:

        >>> l1 = [1,2,3]
        >>> l2 = l1
        >>> l1 = []
        >>> print l2
        [1, 2, 3]

So the original list 'l1' lives on.  However:

        >>> l1 = [1,2,3]
        >>> l2 = l1
        >>> del l1[:]
        >>> print l1, l2
        [] []

Cheers,
Jason.



From tjreedy at udel.edu  Wed Jul 29 11:43:12 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 29 Jul 2009 11:43:12 -0400
Subject: python 3 and stringio.seek
In-Reply-To: <ECDBC5EB-B60D-4F54-81A8-9989C33AA70C@umich.edu>
References: <h4mui9$q1o$1@nnrp-beta.newsland.it>
	<ECDBC5EB-B60D-4F54-81A8-9989C33AA70C@umich.edu>
Message-ID: <h4pqmf$pjc$1@ger.gmane.org>

Miles Kaufmann wrote:
> 
> On Jul 28, 2009, at 6:30 AM, Michele Petrazzo wrote:
> 
>> Hi list,
>> I'm trying to port a my library to python 3, but I have a problem with a
>> the stringio.seek:
>> the method not accept anymore a value like pos=-6 mode=1, but the "old"
>> (2.X) version yes...
>>
>> The error:
>>  File "/home/devel/Py3/lib/python3.0/io.py", line 2031, in seek
>>    return self._seek(pos, whence)
>> IOError: Can't do nonzero cur-relative seeks
>>
>>
>> How solve this?
> 
> In Python 2, StringIO is a stream of bytes (non-Unicode characters).  In 
> Python 3, StringIO is a stream of text (Unicode characters).  In the 
> early development of Python 3 (and 3.1's _pyio), it was implemented as a 
> TextIOWrapper over a BytesIO buffer.  TextIOWrapper does not support 
> relative seeks because it is difficult to map the concept of a "current 
> position" between bytes and the text that it encodes, especially with 
> variable-width encodings and other considerations.  Furthermore, the 
> value returned from TextIOWrapper.tell isn't just a file position but a 
> "cookie" that contains other data necessary to restore the decoding 
> mechanism to the same state.  However, for the default encoding (utf-8), 
> the current position is equivalent to that of the underlying bytes buffer.
> 
> In Python 3, StringIO is implemented using an internal buffer of Unicode 
> characters.  There is no technical reason why it can't support relative 
> seeks; I assume it does not for compatibility with the original Python 
> TextIOWrapper implementation (which is present in 3.1's _pyio, but not 
> in 3.0).
> 
> Note that because of the different implementations, StringIO.tell() (and 
> seek) behaves differently for the C and Python implementations:
> 
> $ python3.1
>  >>> import io, _pyio
>  >>> s = io.StringIO('\u263A'); s.read(1), s.tell()
> ('?', 1)
>  >>> s = _pyio.StringIO('\u263A'); s.read(1), s.tell()
> ('?', 3)

It seems to me that this discrepancy might be worth a tracker item.
I wonder why the second implementation is even there if not used.
Two different commiters?

> The end result seems to be that, for text streams (including StreamIO), 
> you *should* treat the value returned by tell() as an opaque magic 
> cookie, and *only* pass values to seek() that you have obtained from a 
> previous tell() call.  However, in practice, it appears that you *may* 
> seek StringIO objects relatively by characters using s.seek(s.tell() + 
> n), so long as you do not use the _pyio.StringIO implementation.

A tracker item could include a request that relative seek be restored if 
possible.

tjr



From python at mrabarnett.plus.com  Wed Jul 29 11:45:55 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 16:45:55 +0100
Subject: New implementation of re module
In-Reply-To: <215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com>
Message-ID: <4A706EB3.1040501@mrabarnett.plus.com>

Mike wrote:
> On Jul 27, 11:34 am, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> I've been working on a new implementation of the re module.
> 
> Fabulous!
> 
> If you're extending/changing the interface, there are a couple of sore
> points in the current implementation I'd love to see addressed:
> 
> - findall/finditer doesn't find overlapping matches.  Sometimes you
> really *do* want to know all possible matches, even if they overlap.
> This comes up in bioinformatics, for example.
> 
Perhaps by adding "overlapped=True"?

> - split won't split on empty patterns, e.g. empty lookahead patterns.
> This means that it can't be used for a whole class of interesting
> cases.  This has been discussed previously:
> 
>     http://bugs.python.org/issue3262
>     http://bugs.python.org/issue852532
>     http://bugs.python.org/issue988761
> 
Already addressed (see issue2636 for the full details).

> - It'd be nice to have a version of split that generates the parts
> (one by one) rather than returning the whole list.
> 
Hmm, re.splititer() perhaps.

> - Repeated subgroup match information is not available.  That is, for
> a match like this
> 
>     re.match('(.){3}', 'xyz')
> 
> there's no way to discover that the subgroup first matched 'x', then
> matched 'y', and finally matched 'z'.  Here is one past proposal
> (mine), perhaps over-complex, to address this problem:
> 
>     http://mail.python.org/pipermail/python-dev/2004-August/047238.html
> 
Yikes! I think I'll let you code that... :-)


From mdboldin at gmail.com  Wed Jul 29 11:49:49 2009
From: mdboldin at gmail.com (mpython)
Date: Wed, 29 Jul 2009 08:49:49 -0700 (PDT)
Subject: SEC forms parsing
Message-ID: <ffa37df5-3eb9-40d6-929d-397fa80b4fbc@h30g2000vbr.googlegroups.com>

I am looking for any python examples that have written to parse SEC
filings (Security Exchange Commission's EDGAR system),or just a
pointer to best modules to use.


From python at mrabarnett.plus.com  Wed Jul 29 11:53:47 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 16:53:47 +0100
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
Message-ID: <4A70708B.4030402@mrabarnett.plus.com>

Omer Khalid wrote:
> Hi,
> 
> I am having a very strange problem with modifying a variable in a list 
> in my program. Here is the code:
> 
> # a list that contains dictionary objects
> jobs = []
> 
> index=5
> for each in range(index):
>          jobs.append({'v':0})
> 
> some_function(index):
>        if jobs[index]['v'] == 0:
>                    # set it to 1
>                    jobs[index]['v'] = 1
>                    print "Set to 1"
>       else:
>                    print "Already set to 1"
> 
> loop():
>         index=0
>         for each in range(len(jobs)):
>                  some_function(index)
>                  index +=1
> 
> 
> Apparently, the jobs[index]['v'] never get updated in the some_function 
> but the print statement afterwards get printed...
> 
> What's really surprising is that there are no errors or exceptions and 
> my my program runs in a single thread...so i have been unable to explain 
> this behavior.
> 
> Any insight would be much appreciated!
> 
Well, when I insert the missing 'def's in the function definitions, it
works for me.


From ronn.ross at gmail.com  Wed Jul 29 11:57:18 2009
From: ronn.ross at gmail.com (Ronn Ross)
Date: Wed, 29 Jul 2009 10:57:18 -0500
Subject: Can you easy_install from your localhost?
Message-ID: <9c8c445f0907290857x27930acbvc5067a242e18ed17@mail.gmail.com>

I have a package i would like to store locally. If it is stored locally can
I do something like ' easy_install http://localhost/package ' ? Thanks
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/ecf1262c/attachment-0001.html>

From invalid at invalid  Wed Jul 29 12:02:53 2009
From: invalid at invalid (Grant Edwards)
Date: Wed, 29 Jul 2009 11:02:53 -0500
Subject: Compiling Python for uCLinux appliance?
References: <7sk075l5p7eq8mek9ooqj5kr0ds10hrvfq@4ax.com>
	<7db5mnF2bf9i2U1@mid.uni-berlin.de>
Message-ID: <N-SdnVnsn7Yw7-3XnZ2dnUVZ_hGdnZ2d@posted.visi>

On 2009-07-29, Diez B. Roggisch <deets at nospam.web.de> wrote:
> Gilles Ganault wrote:
>
>> Hello
>> 
>> I just got a small appliance based on a Blackfin CPU with 64MB RAM and
>> 258MB NAND flash. Using the stock software, there's about 30MB of RAM
>> left.
>> 
>> Besides C/C++ and shel scripts, I was wondering if it were realistic
>> to upload a few Python scripts in such a small appliance?

The standard uclinux-dist comes with python, so it's pretty
much just a question of memory.  Asking on the uclinux mailing
list will probably be more useful, but I would guess that 64MB
would be plenty -- especially if use JFFS to put your root
filesystem in flash instead of in RAM.  Of course it depends
entirely on what else you want to do with that RAM at the same
time...

> Try & check out the gumstix software repo. It comes with
> python, and thus some crosscompiling/build-instructions should
> be in there.

IIRC, all you have to do is "make menuconfig", go to the user
apps page and check the "Python" box, and then "make".  It
should "just work".

-- 
Grant Edwards                   grante             Yow! I haven't been married
                                  at               in over six years, but we
                               visi.com            had sexual counseling every
                                                   day from Oral Roberts!!


From ryniek90 at gmail.com  Wed Jul 29 12:11:32 2009
From: ryniek90 at gmail.com (Ryniek90)
Date: Wed, 29 Jul 2009 18:11:32 +0200
Subject: how to embed the python interpreter into web App (Mehndi, Sibtey)
In-Reply-To: <mailman.14496.1248881699.8014.python-list@python.org>
References: <mailman.14496.1248881699.8014.python-list@python.org>
Message-ID: <4A7074B4.2070204@gmail.com>

>
>
> Hi All
>
> I am trying to embed the python interpreter in to a web app but could 
> not get the way, any one can suggest me how to do this.
>
>  
>
> Thanks,
>
> Sibtey Mehdi
>
>  
>
> This e-mail (and any attachments), is confidential and may be privileged. It may be read, copied and used only
> by intended recipients. Unauthorized access to this e-mail (or attachments) and disclosure or copying of its 
> contents or any action taken in reliance on it is unlawful. Unintended recipients must notify the sender immediately 
> by e-mail/phone & delete it from their system without making any copies or disclosing it to a third person.
>
>
>   

Here's example: http://try-python.mired.org/

Contact with author of that website/webapp.

Good luck.


From python at mrabarnett.plus.com  Wed Jul 29 12:53:33 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 17:53:33 +0100
Subject: Very Strange Problem
In-Reply-To: <4A7074E6.9030100@gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
	<4A70708B.4030402@mrabarnett.plus.com> <4A7074E6.9030100@gmail.com>
Message-ID: <4A707E8D.4020306@mrabarnett.plus.com>

Ricardo Ar?oz wrote:
> MRAB wrote:
>> Omer Khalid wrote:
>>> Hi,
>>>
>>> I am having a very strange problem with modifying a variable in a 
>>> list in my program. Here is the code:
>>>
>>> # a list that contains dictionary objects
>>> jobs = []
>>>
>>> index=5
>>> for each in range(index):
>>>          jobs.append({'v':0})
>>>
>>> some_function(index):
>>>        if jobs[index]['v'] == 0:
>>>                    # set it to 1
>>>                    jobs[index]['v'] = 1
>>>                    print "Set to 1"
>>>       else:
>>>                    print "Already set to 1"
>>>
>>> loop():
>>>         index=0
>>>         for each in range(len(jobs)):
>>>                  some_function(index)
>>>                  index +=1
>>>
>>>
>>> Apparently, the jobs[index]['v'] never get updated in the 
>>> some_function but the print statement afterwards get printed...
>>>
>>> What's really surprising is that there are no errors or exceptions 
>>> and my my program runs in a single thread...so i have been unable to 
>>> explain this behavior.
>>>
>>> Any insight would be much appreciated!
>>>
>> Well, when I insert the missing 'def's in the function definitions, it
>> works for me.
> Hi Omer, what he is trying to convey in his rude manner is that you are 
> missing "def" in your function definitions. It is probably a beginners 
> mistake.
> 
> That is :
> from "some_function(index): "
> to "def some_function(index): "
> 
> from "loop(): "
> to "def loop(): "
> 
> I have not tried your code so you should believe him when he states he 
> has actually run the code.
> HTH
> 
Omer says "the print statement afterwards get printed", but the code
provided would have raised a SyntaxError, so omitting the 'def's can't
be the cause of the actual problem reported.


From nagle at animats.com  Wed Jul 29 13:10:15 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 29 Jul 2009 10:10:15 -0700
Subject: bad certificate error
In-Reply-To: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
References: <cde18b15-6aa4-412c-b566-9d2a6703de53@a37g2000prf.googlegroups.com>
Message-ID: <4a7081c9$0$1600$742ec2ed@news.sonic.net>

jakecjacobson wrote:
> Hi,
> 
> I am getting the following error when doing a post to REST API,
> 
> Enter PEM pass phrase:
> Traceback (most recent call last):
>   File "./ices_catalog_feeder.py", line 193, in ?
>     main(sys.argv[1])
>   File "./ices_catalog_feeder.py", line 60, in main
>     post2Catalog(catalog_host, catalog_port, catalog_path, os.path.join
> (input_dir, file), collection_name, key_file, cert_file)
>   File "./ices_catalog_feeder.py", line 125, in post2Catalog
>     connection.request('POST', path, parameters, head)
>   File "/usr/lib/python2.4/httplib.py", line 810, in request
>     self._send_request(method, url, body, headers)
>   File "/usr/lib/python2.4/httplib.py", line 833, in _send_request
>     self.endheaders()
>   File "/usr/lib/python2.4/httplib.py", line 804, in endheaders
>     self._send_output()
>   File "/usr/lib/python2.4/httplib.py", line 685, in _send_output
>     self.send(msg)
>   File "/usr/lib/python2.4/httplib.py", line 652, in send
>     self.connect()
>   File "/usr/lib/python2.4/httplib.py", line 1079, in connect
>     ssl = socket.ssl(sock, self.key_file, self.cert_file)
>   File "/usr/lib/python2.4/socket.py", line 74, in ssl
>     return _realssl(sock, keyfile, certfile)
> socket.sslerror: (1, 'error:14094412:SSL
> routines:SSL3_READ_BYTES:sslv3 alert bad certificate')

    What SSL implementation are you using?  The old one from Python 2.4
doesn't even check the certificate chain.  M2Crypto does, and the new
SSL module does, but in each case you have to provide a root certificate
file.  (The one from Mozilla is available.)

					John Nagle


From nagle at animats.com  Wed Jul 29 13:12:27 2009
From: nagle at animats.com (John Nagle)
Date: Wed, 29 Jul 2009 10:12:27 -0700
Subject: SEC forms parsing
In-Reply-To: <ffa37df5-3eb9-40d6-929d-397fa80b4fbc@h30g2000vbr.googlegroups.com>
References: <ffa37df5-3eb9-40d6-929d-397fa80b4fbc@h30g2000vbr.googlegroups.com>
Message-ID: <4a70824d$0$1600$742ec2ed@news.sonic.net>

mpython wrote:
> I am looking for any python examples that have written to parse SEC
> filings (Security Exchange Commission's EDGAR system),or just a
> pointer to best modules to use.

    I've been doing that in Perl for years.  See "www.downside.com".

    Actually extracting financial statements is possible, but you
run into a patent problem with a Price-Waterhouse patent if you try
to do a good job.

    What are you trying to do?

				John Nagle


From piet at cs.uu.nl  Wed Jul 29 13:17:51 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 29 Jul 2009 19:17:51 +0200
Subject: Help with sql and python
References: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>
Message-ID: <m2bpn3e7cw.fsf@cs.uu.nl>

>>>>> "catalinfest at gmail.com" <catalinfest at gmail.com> (cc) wrote:

>cc> Hello !
>cc> I have accont on myphpadmin on my server.
>cc> I want to create one script in python.
>cc> This script manage sql task from my sql server .
>cc> How i make this in a simple way ?

See http://mysql-python.sourceforge.net/MySQLdb.html

This really has nothing to do with myphpadmin (you probably mean
phpMyAdmin but even then it has nothing to do with it except that both
acess a MySQL database).

And if you give yourself a name than we might have an idea if we are
talking to a human being or a robot.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From tutufan at gmail.com  Wed Jul 29 13:21:39 2009
From: tutufan at gmail.com (Mike)
Date: Wed, 29 Jul 2009 10:21:39 -0700 (PDT)
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org> 
	<215e5098-9181-4fec-b563-f8851d3bb491@v36g2000yqv.googlegroups.com> 
	<mailman.3899.1248882356.8015.python-list@python.org>
Message-ID: <19a1cbfa-6594-4956-bc3c-f1fd3108091a@c29g2000yqd.googlegroups.com>

On Jul 29, 10:45?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Mike wrote:
> > - findall/finditer doesn't find overlapping matches. ?Sometimes you
> > really *do* want to know all possible matches, even if they overlap.
>
> Perhaps by adding "overlapped=True"?

Something like that would be great, yes.


> > - split won't split on empty patterns, e.g. empty lookahead patterns.

> Already addressed (see issue2636 for the full details).

Glad to hear it.


> > - Repeated subgroup match information is not available. ?That is, for
> > a match like this
>
> > ? ? re.match('(.){3}', 'xyz')
>
> > there's no way to discover that the subgroup first matched 'x', then
> > matched 'y', and finally matched 'z'. ?Here is one past proposal
> > (mine), perhaps over-complex, to address this problem:
>
> > ? ?http://mail.python.org/pipermail/python-dev/2004-August/047238.html
>
> Yikes! I think I'll let you code that... :-)

I agree that that document looks a little scary--maybe I was trying to
bite off too much at once.

My intuition, though, is that the basic idea should be fairly simple
to implement, at least for a depth-first matcher.  The repeated match
subgroups are already being discovered, it's just that they're not
being saved, so there's no way to report them out once a complete
match is found.  If some trail of breadcrumbs were pushed onto a stack
during the DFS, it could be traced at the end.  And the whole thing
might not even been that expensive to do.

The hardest parts about this, in my mind, are figuring out how to
report the repeated matches out in a useful form (hence all that
detail in the proposal), and getting users to understand that using
this feature *could* suck up a lot of memory, if they're not careful.

As always, it's possible that my intuition is totally wrong.  Plus I'm
not sure how this would work out in the breadth-first case.

Details aside, I would really, really, really like to have a way to
get at the repeated subgroup matches.  I write a lot of code that
would be one-liners if this capability existed.  Plus, it just plain
burns me that Python is discovering this information but impudently
refuses to tell me what it's found!  ;-)




From piet at cs.uu.nl  Wed Jul 29 13:26:26 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Wed, 29 Jul 2009 19:26:26 +0200
Subject: open a file in python
References: <5f84b536-dbaf-4758-b78e-ed9d10c57daa@h31g2000yqd.googlegroups.com>
	<mailman.3759.1248682196.8015.python-list@python.org>
	<cc4509ef-0c4a-473c-8b1a-2059456176fb@s15g2000yqs.googlegroups.com>
	<7d5brmF2a1alcU1@mid.uni-berlin.de>
	<2b5b00b8-f9ba-4d16-b950-681aa6fa010a@24g2000yqm.googlegroups.com>
Message-ID: <m27hxre6yl.fsf@cs.uu.nl>

>>>>> jayshree <jayshree06comp at gmail.com> (j) wrote:

>>> The Exact Problem is how to use the key containing by .pem file for
>>> 'encryption' . can i print the contents of the .pem file

I have already answered this question in a previous thread. It is not
very helpful if you repeat asking the same or similar questions in
different threads, especially if you don't take notice of the answers
given. I will repeat it once here:

load_pub_key requires a file name, not the contents of the file.
So use rsa = M2Crypto.RSA.load_pub_key('my_key.public.pem') and leave
the open line out.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From dandi.kain at gmail.com  Wed Jul 29 13:59:55 2009
From: dandi.kain at gmail.com (dandi kain)
Date: Wed, 29 Jul 2009 10:59:55 -0700 (PDT)
Subject: Does underscore has any special built-in meaningin Python ?
Message-ID: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>

Hello everybody,
I have just started learning Python.I heard its simple so I pick a
presentation [1] and tried to work on it.But when it comes to
underscores leading and trailing an object I dont understand any.I
look through the python manual also but that was not helping .I
searched some forums and I still dont have a clear picture.

What is the functionality of __ or _ , leading or trailing an object ,
class ot function ? Is it just a naming convention to note special
functions and objects , or it really mean someting to Python ?

Thanks ahead ,

[1] http://www.aleax.it/goo_py4prog.pdf


From lemmath at gmail.com  Wed Jul 29 14:04:49 2009
From: lemmath at gmail.com (Vincent Vega)
Date: Wed, 29 Jul 2009 11:04:49 -0700 (PDT)
Subject: Print value CLOB via cx_Oracle
References: <6de8842b-f1c6-460e-a705-4f6dbd81492c@a26g2000yqn.googlegroups.com>
Message-ID: <372c160b-eee2-46f3-913c-f75d84f45e11@c14g2000yqm.googlegroups.com>

On 28 Lip, 20:02, Vincent Vega <lemm... at gmail.com> wrote:
> Hi,
>
> I call function in Oracle database use cx_Oracle.
> In standard I define:
>
> db ? ? ? = cx_Oracle.connect(username, password, tnsentry)
> cursor ?= db.cursor()
>
> I create variable 'y' (result function 'fun_name') and call function
> 'fun_name':
>
> y ? = cursor.var(cx_Oracle.CLOB)
> cursor.callfunc(fun_name, cx_Oracle.CLOB, y)
>
> When I print variable 'y' I receive:
> <cx_Oracle.CLOB with value <cx_Oracle.LOB object at 0x00999999>>
>
> How can I get value variable 'y'???
> How read <cx_Oracle.LOB object at 0x00999999>???
>
> Vincent Vega
>
> Note:
> Off course y.read() does not work, cause 'y'is CLOB not LOB.
> (see datatypes table in site:http://www.oracle.com/technology/pub/articles/prez-python-queries.html)

The solution is simple:

print y.getvalue()

(see: http://cx-oracle.sourceforge.net/html/variable.html)

Thanks! :)

Vincent Vega


From davea at ieee.org  Wed Jul 29 14:05:28 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:05:28 -0400
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
Message-ID: <4A708F68.1010505@ieee.org>

Barak, Ron wrote:
> Hi,
>
> I wanted to make a python byte-code file executable, expecting to be able to run it without specifying "python" on the (Linux bash) command line.
>
> So, I wrote the following:
>
> [root at VMLinux1 python]# cat test_pyc.py
> #!/usr/bin/env python
>
> print "hello"
> [root at VMLinux1 python]#
>
> and made its pyc file executable:
>
> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> [root at VMLinux1 python]#
>
> So, I see:
>
> [root at VMLinux1 python]# file test_pyc.py*
> test_pyc.py:  a python script text executable
> test_pyc.pyc: python 2.3 byte-compiled
> [root at VMLinux1 python]#
>
> If I try to do the following, no problem:
>
> [root at VMLinux1 python]# python test_pyc.pyc
> hello
> [root at VMLinux1 python]#
>
> However, the following fails:
>
> [root at VMLinux1 python]# ./test_pyc.pyc
> -bash: ./test_pyc.pyc: cannot execute binary file
> [root at VMLinux1 python]#
>
> Is there a way to run a pyc file without specifying the python path ?
>
> Bye,
> Ron.
>
>   
I don't currently run Unix, but I think I know the problem.

In a text file, the shell examines the first line, and if it begins #! 
it's assumed to point to the executable of an interpreter for that text 
file.  Presumably the same trick doesn't work for a .pyc file.

Why not write a trivial wrapper.py file, don't compile it, and let that 
invoke the main code in the .pyc file?

Then make wrapper.py executable, and you're ready to go.

DaveA



From benjamin.kaplan at case.edu  Wed Jul 29 14:08:07 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Wed, 29 Jul 2009 14:08:07 -0400
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>

On Wed, Jul 29, 2009 at 1:59 PM, dandi kain <dandi.kain at gmail.com> wrote:
>
> Hello everybody,
> I have just started learning Python.I heard its simple so I pick a
> presentation [1] and tried to work on it.But when it comes to
> underscores leading and trailing an object I dont understand any.I
> look through the python manual also but that was not helping .I
> searched some forums and I still dont have a clear picture.
>
> What is the functionality of __ or _ , leading or trailing an object ,
> class ot function ? Is it just a naming convention to note special
> functions and objects , or it really mean someting to Python ?

It's just a convention for the most part. A single leading underscore
is used for "private" attributes. Two leading underscores will affect
the code- it mangles the variable name so that you don't have to worry
about the value being overwritten by a subclass. For instance
"""
class Foo(object) :
   def __init__(self) :
       self.__bar = ''

foo = Foo()
""
will store the attribute as foo._Foo__bar.

Also, the "magic methods"- the ones that are used for operations and
built-in stuff, all have two leading and two trailing underscores.
These are things like __add__ (+), __eq__ (=), __cmp__ (old way for
comparisons), __len__ (len), __str__ (str), and so on.


>
> Thanks ahead ,
>
> [1] http://www.aleax.it/goo_py4prog.pdf
> --
> http://mail.python.org/mailman/listinfo/python-list


From martin.hellwig at dcuktec.org  Wed Jul 29 14:16:31 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Wed, 29 Jul 2009 19:16:31 +0100
Subject: simple splash screen?
In-Reply-To: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
Message-ID: <LYudnbbBM-OdD-3XnZ2dnUVZ8opi4p2d@bt.com>

NighterNet wrote:
> I am trying to make a simple splash screen from python 3.1.Not sure
> where to start looking for it. Can any one help?

Sure, almost the same as with Python 2 :-)
But to be a bit more specific:
++++
"""Only works if you got Python 3 installed with tkinter"""
import tkinter

IMAGE_PATH = "/path/to/image"

class Splash(object):
     "Splash Screen GUI"
     def __init__(self, root):
         self.root = root
         # No window borders and decoration
         self.root.overrideredirect(True)
         # Get the size of the screen
         screen_width = self.root.winfo_screenwidth()
         screen_height = self.root.winfo_screenheight()
         # Full screen
         geometry_text = "%dx%d+0+0" % (screen_width, screen_height)
         self.root.geometry(geometry_text)
         # Display an image
         self.label = tkinter.Label(self.root)
         # Only GIF and PGM/PPM supported, for more information see:
         self.label._image = tkinter.PhotoImage(file=IMAGE_PATH)
         # http://effbot.org/tkinterbook/photoimage.htm
         self.label.configure(image = self.label._image)
         self.label.pack()
         # This will quit the screen after about 5 seconds
         self.root.after(5000, self.root.quit)

if __name__ == '__main__':
     ROOT = tkinter.Tk()
     APPL = Splash(ROOT)
     ROOT.mainloop()
++++

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From davea at ieee.org  Wed Jul 29 14:19:32 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:19:32 -0400
Subject: Help with sql and python
In-Reply-To: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>
References: <3e53d632-0e8a-4d15-8409-8d0dd8ce3b47@o6g2000yqj.googlegroups.com>
Message-ID: <4A7092B4.8090609@ieee.org>

catalinfest at gmail.com wrote:
> Hello !
>
> I have accont on myphpadmin on my server.
> I want to create one script in python.
> This script manage sql task from my sql server .
> How i make this in a simple way ?
>
> Thank you !
>
>   
It's seldom simple.

I'm guessing it's not your server, but is actually a webserver, located 
remotely, and to which you have only ftp access.

Next questions are do you have access to the admins of the machine, what 
kind of machine is it, what OS is it running, does it have Python 
installed, what version(s)?

Next questions are dependent on the answers to those questions.  For 
example, on Unix systems you'll generally need to be able to chmod the file.

But before you ask your admins those questions, you need to ask how you 
*want* to run the script.  Creating it isn't enough, if you don't run 
it.  You might be running it over the web, via URL, perhaps using CGI.  
You might be activating it via some remote console, or rsh.  Or it might 
be a cron job.  It might need various privileges to do what you expect.  
And if it's going to run continuously, or if it uses lots of resources, 
the admins may refuse it entirely.

DaveA



From electriclightheads at gmail.com  Wed Jul 29 14:26:47 2009
From: electriclightheads at gmail.com ('2+)
Date: Thu, 30 Jul 2009 03:26:47 +0900
Subject: instead of depending on data = array('h') .. write samples 1 by 1
	to w = wave.open("wav.wav", "w")
In-Reply-To: <h4p0p8$l9k$01$1@news.t-online.com>
References: <mailman.3855.1248811181.8015.python-list@python.org>
	<h4p0p8$l9k$01$1@news.t-online.com>
Message-ID: <1078018b0907291126t32c453a7h1f2a86fc270d3701@mail.gmail.com>

o wow .. there's still a lot to learn ..
okay .. if i get stucked with the memory usage issue
will try this hybrid .. thanx for the example!!

it took about 40 min to render 1min of wav
so i'll just keep this project like 15 sec oriented
and maybe that'll keep me away from the mem trouble

and my oil.py is still so cheap..
sad thing is that "the result sound strange" is true to
all versions :s

thanx again anyway!


On Wed, Jul 29, 2009 at 5:21 PM, Peter Otten<__peter__ at web.de> wrote:
> '2+ wrote:
>
>> it says
>> Wave_write.writeframes(data)
>> will that mean
>> "from array import array"
>> is a must?
>>
>> this does the job:
>>
>> import oil
>> import wave
>> from array import array
>>
>> a = oil.Sa()
>>
>> w = wave.open("current.wav", "w")
>> w.setnchannels(2)
>> w.setsampwidth(2)
>> w.setframerate(44100)
>>
>> data = array('h')
>>
>> for gas in range(44100 * 5):
>> ? ? a.breath()
>> ? ? r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>> ? ? l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>> ? ? data.append(r)
>> ? ? data.append(l)
>>
>> w.writeframes(data.tostring())
>> w.close()
>>
>> don't like array becoming so huge so tested this and it was also okay:
>>
>> for gas in range(44100 * 5):
>> ? ? a.breath()
>> ? ? data = array('h')
>> ? ? r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>> ? ? l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>> ? ? data.append(r)
>> ? ? data.append(l)
>> ? ? w.writeframes(data.tostring())
>>
>> but without array .. it becomes 15secs(3 times longer than was
>> intended to be) of wav file:
>>
>> for gas in range(44100 * 5):
>> ? ? a.breath()
>> ? ? r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
>> ? ? l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
>> ? ? w.writeframes(hex(r))
>> ? ? w.writeframes(hex(l))
>
> Doesn't it sound strange, too? You are writing bogus bytes to the file.
> Compare:
>
>>>> import array
>>>> array.array("h", [42]).tostring()
> '*\x00'
>>>> hex(42)
> '0x2a'
>
> Not only do they differ in length, the contents are different, too. If
> you're unfamiliar with string escape codes, here's a way to see the bytes:
>
>>>> map(ord, array.array("h", [42]).tostring())
> [42, 0]
>>>> map(ord, hex(42))
> [48, 120, 50, 97]
>
>> should i just be happy with depennding on using array?
>> or is there a solution to make the last one work properly?
>
> There is a way to make the last one work: use struct.pack("h", r) instead of
> hex(r). I'm of course assuming that the first version does give you the
> desired result. You should not continue before you have verified that.
>
> I still recommend array for performance reasons. If memory usage is an issue
> you can adopt a hybrid approach:
>
> # untested
> from itertools import islice
> from array import array
>
> def gen_data():
> ? ?for gas in xrange(44100 * 5): # range --> xrange
> ? ? ? ?a.breath()
> ? ? ? ?r = int(32767 * (a.pulse(1) + a.pulse(2) + a.pulse(3)) / 3.0)
> ? ? ? ?l = int(32767 * (a.pulse(4) + a.pulse(5) + a.pulse(6)) / 3.0)
> ? ? ? ?yield r
> ? ? ? ?yield l
>
> data = gen_data()
> N = 2**20
> while True:
> ? ?chunk = array('h')
> ? ?chunk.extend(islice(data, N))
> ? ?if not chunk:
> ? ? ? ?break
> ? ?w.writeframes(chunk.tostring())
>
> This will limit the array size to 4N bytes.
>
> Peter
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
SaRiGaMa's Oil Vending Orchestra
is podcasting:
http://sarigama.namaste.jp/podcast/rss.xml
and supplying oil.py for free:
http://oilpy.blogspot.com/


From davea at ieee.org  Wed Jul 29 14:33:25 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:33:25 -0400
Subject: escaping characters in filenames
In-Reply-To: <854osv7h2k.fsf@agentultra.com>
References: <854osv7h2k.fsf@agentultra.com>
Message-ID: <4A7095F5.6090100@ieee.org>

J Kenneth King wrote:
> I wrote a script to process some files using another program.  One thing
> I noticed was that both os.listdir() and os.path.walk() will return
> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
> module or recipe that escapes file names and was wondering if anyone
> could point me in the right direction.
>
> As an aside, the script is using subprocess.call() with the "shell=True"
> parameter.  There isn't really a reason for doing it this way (was just
> the fastest way to write it and get a prototype working).  I was
> wondering if Popen objects were sensitive to unescaped names like the
> shell.  I intend to refactor the function to use Popen objects at some
> point and thought perhaps escaping file names may not be entirely
> necessary.
>
> Cheers
>
>   
There are dozens of meanings for escaping characters in strings.  
Without some context, we're wasting our time.

For example, if the filename is to be interpreted as part of a URL, then 
spaces are escaped by using %20.   Exactly who is going to be using this 
string you think you have to modify?  I don't know of any environment 
which expects spaces to be escaped with backslashes.

Be very specific.  For example, if a Windows application is parsing its 
own command line, you need to know what that particular application is 
expecting -- Windows passes the entire command line as a single string.  
But of course you may be invoking that application using 
subprocess.Popen(), in which case some transformations happen to your 
arguments before the single string is built.  Then some more 
transformations may happen in the shell.  Then some more in the C 
runtime library of the new process (if it happens to be in C, and if it 
happens to use those libraries).

I'm probably not the one with the answer.  But until you narrow down 
your case, you probably won't attract the attention of whichever person 
has the particular combination of experience that you're hoping for.

DaveA



From jdgiotta at gmail.com  Wed Jul 29 14:39:55 2009
From: jdgiotta at gmail.com (John D Giotta)
Date: Wed, 29 Jul 2009 11:39:55 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
Message-ID: <cbfcfb6e-ca37-4631-b25c-e0162a53d426@32g2000yqj.googlegroups.com>

I'm working with up to 3 process "session" per server, each process
running three threads.
I was wishing to tie back the 3 "session"/server to a semaphore, but
everything (and everyone) say semaphores are only good per process.


From jdgiotta at gmail.com  Wed Jul 29 14:43:07 2009
From: jdgiotta at gmail.com (John D Giotta)
Date: Wed, 29 Jul 2009 11:43:07 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<m2bpn44c8i.fsf@valheru.db3l.homeip.net>
Message-ID: <171f69c0-44ae-4624-bd03-a47032e82c21@n11g2000yqb.googlegroups.com>

That was my original idea. Restricting each process by pid:

#bash
procs=`ps aux | grep script.pl | grep -v grep | wc -l`

if [ $procs -lt 3 ]; then
        python2.4 script.py config.xml
else
        exit 0
fi


From lists at cheimes.de  Wed Jul 29 14:53:49 2009
From: lists at cheimes.de (Christian Heimes)
Date: Wed, 29 Jul 2009 20:53:49 +0200
Subject: Semaphore Techniques
In-Reply-To: <cbfcfb6e-ca37-4631-b25c-e0162a53d426@32g2000yqj.googlegroups.com>
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
	<cbfcfb6e-ca37-4631-b25c-e0162a53d426@32g2000yqj.googlegroups.com>
Message-ID: <h4q5rt$us8$1@ger.gmane.org>

John D Giotta schrieb:
> I'm working with up to 3 process "session" per server, each process
> running three threads.
> I was wishing to tie back the 3 "session"/server to a semaphore, but
> everything (and everyone) say semaphores are only good per process.

That's not true. Named semaphores are the best solution for your problem
and I said so yesterday.

Christian



From nobody at nowhere.com  Wed Jul 29 14:55:16 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 19:55:16 +0100
Subject: escaping characters in filenames
References: <854osv7h2k.fsf@agentultra.com>
Message-ID: <pan.2009.07.29.18.55.16.468000@nowhere.com>

On Wed, 29 Jul 2009 09:29:55 -0400, J Kenneth King wrote:

> I wrote a script to process some files using another program.  One thing
> I noticed was that both os.listdir() and os.path.walk() will return
> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
> module or recipe that escapes file names and was wondering if anyone
> could point me in the right direction.
> 
> As an aside, the script is using subprocess.call() with the "shell=True"
> parameter.  There isn't really a reason for doing it this way (was just
> the fastest way to write it and get a prototype working).  I was
> wondering if Popen objects were sensitive to unescaped names like the
> shell.  I intend to refactor the function to use Popen objects at some
> point and thought perhaps escaping file names may not be entirely
> necessary.

Note that subprocess.call() is nothing more than:

	def call(*popenargs, **kwargs):
	    return Popen(*popenargs, **kwargs).wait()

plus a docstring. It accepts exactly the same arguments as Popen(), with
the same semantics.

If you want to run a command given a program and arguments, you
should pass the command and arguments as a list, rather than trying to
construct a string.

On Windows the value of shell= is unrelated to whether the command is
a list or a string; a list is always converted to string using the
list2cmdline() function. Using shell=True simply prepends "cmd.exe /c " to
the string (this allows you to omit the .exe/.bat/etc extension for
extensions which are in %PATHEXT%).

On Unix, a string is first converted to a single-element list, so if you
use a string with shell=False, it will be treated as the name of an
executable to be run without arguments, even if contains spaces, shell
metacharacters etc.

The most portable approach seems to be to always pass the command as a
list, and to set shell=True on Windows and shell=False on Unix.

The only reason to pass a command as a string is if you're getting a
string from the user and you want it to be interpreted using the
platform's standard shell (i.e. cmd.exe or /bin/sh). If you want it to be
interpreted the same way regardless of platform, parse it into a
list using shlex.split().



From mdekauwe at gmail.com  Wed Jul 29 14:56:28 2009
From: mdekauwe at gmail.com (Martin)
Date: Wed, 29 Jul 2009 11:56:28 -0700 (PDT)
Subject: set variable to looping index?
Message-ID: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>

Hi,

I am trying to set the return value from a function to a name which I
grab from the for loop. I can't work out how I can do this without
using an if statement...

for f in var1_fn, var2_fn, var3_fn:
    if f.split('.')[0] == 'var1':
        var1 = call_some_function(f)
	.
        .
        .
      etc

 Really I would like to remove the need for this if loop and I am sure
there is a simple way I am missing?

Many thanks

Martin



From davea at ieee.org  Wed Jul 29 14:56:55 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 14:56:55 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
Message-ID: <4A709B77.9080209@ieee.org>

Omer Khalid wrote:
> Hi,
>
> I am having a very strange problem with modifying a variable in a list in my
> program. Here is the code:
>
> # a list that contains dictionary objects
> jobs = []
>
> index=5
> for each in range(index):
>          jobs.append({'v':0})
>
> some_function(index):
>        if jobs[index]['v'] == 0:
>                    # set it to 1
>                    jobs[index]['v'] = 1
>                    print "Set to 1"
>       else:
>                    print "Already set to 1"
>
> loop():
>         index=0
>         for each in range(len(jobs)):
>                  some_function(index)
>                  index +=1
>
>
> Apparently, the jobs[index]['v'] never get updated in the some_function but
> the print statement afterwards get printed...
>
> What's really surprising is that there are no errors or exceptions and my my
> program runs in a single thread...so i have been unable to explain this
> behavior.
>
> Any insight would be much appreciated!
>
> Cheers
> Omer
>
>   
There are four things to fix before the program does anything much at 
all.  Two places you're missing the def, indentation is inconsistent, 
and you never actually call either of the functions.   The first three 
are syntax errors, so presumably your cut/paste in your computer is broken.

Once I make those four corrections, I get the following output:

Set to 1
Set to 1
Set to 1
Set to 1
Set to 1

But you never said what you got, nor what you expected.  That's 
certainly what I'd expect.  And if you make a second call to loop() in 
your outer code, you get five copies of "Already set to 1"

BTW, there are a number of things that could be done better.  The main 
one I'll point out is that you shouldn't re-use a global variable 
'index' as a local with different meaning.  As someone else pointed out, 
since the global is a constant, making it all uppercase is the convention.

DaveA



From martin at v.loewis.de  Wed Jul 29 15:06:31 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Wed, 29 Jul 2009 21:06:31 +0200
Subject: 64-bit issues with dictionaries in Python 2.6
In-Reply-To: <hpe5k6-ed5.ln1@nb2.stroeder.com>
References: <hpe5k6-ed5.ln1@nb2.stroeder.com>
Message-ID: <4a709db7$0$15886$9b622d9e@news.freenet.de>

> Are there any known issues with dictionaries in Python 2.6 (not 2.6.2)
> when running on a 64-bit platform?

No, none.

Regards,
Martin


From Omer.Khalid at cern.ch  Wed Jul 29 15:10:44 2009
From: Omer.Khalid at cern.ch (Omer Khalid)
Date: Wed, 29 Jul 2009 21:10:44 +0200
Subject: Very Strange Problem
In-Reply-To: <4A709B77.9080209@ieee.org>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com> 
	<4A709B77.9080209@ieee.org>
Message-ID: <77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>

Hi Dave,

Thanks for your reply. I actually didn't cut and paste my code as it was
dispersed in different places, i typed the logic behind my code in the email
(and obiviously made some typos, indentations is some thing else) but my
real code does not have these problems as my application runs fine with out
errors...

Except that the line where i want to update the value doesn't get updated
and no exception is thrown. What's surprising for me is that i am doing the
same thing in hundreds of places in my 3k+ line code but by some reason this
part doesn't work...

As far as the global variables are concerned, i am using them in other
places too and didn't see any problems.

I think some thing else is going on here as the statement above and below my
modified lines get executed.

Is there a way in Python to debug memory address or to see where in memory
this object is stored, and is there a lock on it or else?

Thanks,
Omer


**************************************


On Wed, Jul 29, 2009 at 8:56 PM, Dave Angel <davea at ieee.org> wrote:

> Omer Khalid wrote:
>
>> Hi,
>>
>> I am having a very strange problem with modifying a variable in a list in
>> my
>> program. Here is the code:
>>
>> # a list that contains dictionary objects
>> jobs = []
>>
>> index=5
>> for each in range(index):
>>         jobs.append({'v':0})
>>
>> some_function(index):
>>       if jobs[index]['v'] == 0:
>>                   # set it to 1
>>                   jobs[index]['v'] = 1
>>                   print "Set to 1"
>>      else:
>>                   print "Already set to 1"
>>
>> loop():
>>        index=0
>>        for each in range(len(jobs)):
>>                 some_function(index)
>>                 index +=1
>>
>>
>> Apparently, the jobs[index]['v'] never get updated in the some_function
>> but
>> the print statement afterwards get printed...
>>
>> What's really surprising is that there are no errors or exceptions and my
>> my
>> program runs in a single thread...so i have been unable to explain this
>> behavior.
>>
>> Any insight would be much appreciated!
>>
>> Cheers
>> Omer
>>
>>
>>
> There are four things to fix before the program does anything much at all.
>  Two places you're missing the def, indentation is inconsistent, and you
> never actually call either of the functions.   The first three are syntax
> errors, so presumably your cut/paste in your computer is broken.
>
> Once I make those four corrections, I get the following output:
>
> Set to 1
> Set to 1
> Set to 1
> Set to 1
> Set to 1
>
> But you never said what you got, nor what you expected.  That's certainly
> what I'd expect.  And if you make a second call to loop() in your outer
> code, you get five copies of "Already set to 1"
>
> BTW, there are a number of things that could be done better.  The main one
> I'll point out is that you shouldn't re-use a global variable 'index' as a
> local with different meaning.  As someone else pointed out, since the global
> is a constant, making it all uppercase is the convention.
>
> DaveA
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/11d04716/attachment-0001.html>

From darkneter at gmail.com  Wed Jul 29 15:32:10 2009
From: darkneter at gmail.com (NighterNet)
Date: Wed, 29 Jul 2009 12:32:10 -0700 (PDT)
Subject: simple splash screen?
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
	<LYudnbbBM-OdD-3XnZ2dnUVZ8opi4p2d@bt.com>
Message-ID: <79954da5-a437-48a1-985b-88abe601d021@a37g2000prf.googlegroups.com>

On Jul 29, 11:16?am, "Martin P. Hellwig" <martin.hell... at dcuktec.org>
wrote:
> NighterNet wrote:
> > I am trying to make a simple splash screen from python 3.1.Not sure
> > where to start looking for it. Can any one help?
>
> Sure, almost the same as with Python 2 :-)
> But to be a bit more specific:
> ++++
> """Only works if you got Python 3 installed with tkinter"""
> import tkinter
>
> IMAGE_PATH = "/path/to/image"
>
> class Splash(object):
> ? ? ?"Splash Screen GUI"
> ? ? ?def __init__(self, root):
> ? ? ? ? ?self.root = root
> ? ? ? ? ?# No window borders and decoration
> ? ? ? ? ?self.root.overrideredirect(True)
> ? ? ? ? ?# Get the size of the screen
> ? ? ? ? ?screen_width = self.root.winfo_screenwidth()
> ? ? ? ? ?screen_height = self.root.winfo_screenheight()
> ? ? ? ? ?# Full screen
> ? ? ? ? ?geometry_text = "%dx%d+0+0" % (screen_width, screen_height)
> ? ? ? ? ?self.root.geometry(geometry_text)
> ? ? ? ? ?# Display an image
> ? ? ? ? ?self.label = tkinter.Label(self.root)
> ? ? ? ? ?# Only GIF and PGM/PPM supported, for more information see:
> ? ? ? ? ?self.label._image = tkinter.PhotoImage(file=IMAGE_PATH)
> ? ? ? ? ?#http://effbot.org/tkinterbook/photoimage.htm
> ? ? ? ? ?self.label.configure(image = self.label._image)
> ? ? ? ? ?self.label.pack()
> ? ? ? ? ?# This will quit the screen after about 5 seconds
> ? ? ? ? ?self.root.after(5000, self.root.quit)
>
> if __name__ == '__main__':
> ? ? ?ROOT = tkinter.Tk()
> ? ? ?APPL = Splash(ROOT)
> ? ? ?ROOT.mainloop()
> ++++
>
> --
> MPHhttp://blog.dcuktec.com
> 'If consumed, best digested with added seasoning to own preference.'

Thanks it help. Sorry about that, I was just wander what kind of
answer and if there are other methods to learn it.

Is there a way to position image to the center screen?


From tjreedy at udel.edu  Wed Jul 29 15:41:34 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 29 Jul 2009 15:41:34 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
Message-ID: <h4q8ld$8hc$1@ger.gmane.org>

Omer Khalid wrote:
> Hi,
> 
> I am having a very strange problem with modifying a variable in a list 
> in my program. Here is the code:

To me, this sentence clearly implies that the code that follows is the 
code that had the problem. Since the posted code cannot run, it clearly 
is not. People should test code to be posted before posting unless they 
clearly label it as 'untested'. Original posters, of course, should run 
the code first.

tjr



From davea at ieee.org  Wed Jul 29 15:42:39 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 15:42:39 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
	<4A709B77.9080209@ieee.org>
	<77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
Message-ID: <4A70A62F.6080403@ieee.org>

Omer Khalid wrote:
> Hi Dave,
>
> Thanks for your reply. I actually didn't cut and paste my code as it was
> dispersed in different places, i typed the logic behind my code in the email
> (and obiviously made some typos, indentations is some thing else) but my
> real code does not have these problems as my application runs fine with out
> errors...
>
> Except that the line where i want to update the value doesn't get updated
> and no exception is thrown. What's surprising for me is that i am doing the
> same thing in hundreds of places in my 3k+ line code but by some reason this
> part doesn't work...
>
> As far as the global variables are concerned, i am using them in other
> places too and didn't see any problems.
>
> I think some thing else is going on here as the statement above and below my
> modified lines get executed.
>
> Is there a way in Python to debug memory address or to see where in memory
> this object is stored, and is there a lock on it or else?
>
> Thanks,
> Omer
>
>
> **************************************
>
>
> On Wed, Jul 29, 2009 at 8:56 PM, Dave Angel <davea at ieee.org> wrote:
>
>   
>> Omer Khalid wrote:
>>
>>     
>>> Hi,
>>>
>>> I am having a very strange problem with modifying a variable in a list in
>>> my
>>> program. Here is the code:
>>>
>>> # a list that contains dictionary objects
>>> jobs = []
>>>
>>> index=5
>>> for each in range(index):
>>>         jobs.append({'v':0})
>>>
>>> some_function(index):
>>>       if jobs[index]['v'] == 0:
>>>                   # set it to 1
>>>                   jobs[index]['v'] = 1
>>>                   print "Set to 1"
>>>      else:
>>>                   print "Already set to 1"
>>>
>>> loop():
>>>        index=0
>>>        for each in range(len(jobs)):
>>>                 some_function(index)
>>>                 index +=1
>>>
>>>
>>> Apparently, the jobs[index]['v'] never get updated in the some_function
>>> but
>>> the print statement afterwards get printed...
>>>
>>> What's really surprising is that there are no errors or exceptions and my
>>> my
>>> program runs in a single thread...so i have been unable to explain this
>>> behavior.
>>>
>>> Any insight would be much appreciated!
>>>
>>> Cheers
>>> Omer
>>>
>>>
>>>
>>>       
>> There are four things to fix before the program does anything much at all.
>>  Two places you're missing the def, indentation is inconsistent, and you
>> never actually call either of the functions.   The first three are syntax
>> errors, so presumably your cut/paste in your computer is broken.
>>
>> Once I make those four corrections, I get the following output:
>>
>> Set to 1
>> Set to 1
>> Set to 1
>> Set to 1
>> Set to 1
>>
>> But you never said what you got, nor what you expected.  That's certainly
>> what I'd expect.  And if you make a second call to loop() in your outer
>> code, you get five copies of "Already set to 1"
>>
>> BTW, there are a number of things that could be done better.  The main one
>> I'll point out is that you shouldn't re-use a global variable 'index' as a
>> local with different meaning.  As someone else pointed out, since the global
>> is a constant, making it all uppercase is the convention.
>>
>> DaveA
>>
>>     
(You top-posted, so your ,message is out of sequence.  More and more 
people are doing that in this list.)


++++  ...Except that the line where i want to update the value doesn't 
get updated...

And what makes you think that?  You never answered my question.  What did you expect for output, and what did you get?  I got exactly what I expected, when I ran it.

++++ ...  Is there a way in Python to debug memory address or
++++      to see where in memory this object is stored, and
++++      is there a lock on it or else?

If there really were a bug in the language, you might need such a tool.  
I use Komodo IDE as a debugger, but there was no need in this case.  
Adding a few print statements might clear up your confusion, but since 
you haven't spelled out what it is, I can't suggest where.  How about if 
you just add a    print jobs    at the beginning of some_function() ?  
Then you could see things getting updated perfectly.

DaveA



From zuo at chopin.edu.pl  Wed Jul 29 15:54:51 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Wed, 29 Jul 2009 21:54:51 +0200
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
Message-ID: <op.uxuhlpetfvx12t@jerzozwiesz.home.aster.pl>

29-07-2009 Benjamin Kaplan <benjamin.kaplan at case.edu> wrote:

> On Wed, Jul 29, 2009 at 1:59 PM, dandi kain <dandi.kain at gmail.com> wrote:
[snip
>> What is the functionality of __ or _ , leading or trailing an object ,
>> class ot function ? Is it just a naming convention to note special
>> functions and objects , or it really mean someting to Python ?
>
> It's just a convention for the most part. A single leading underscore
> is used for "private" attributes. Two leading underscores will affect
> the code-

Single leading underscore in some situations also affect the code...

See:

*  
http://docs.python.org/reference/lexical_analysis.html#reserved-classes-of-identifiers

* http://docs.python.org/reference/datamodel.html#object.__del__
   (in the the red "Warning" frame)

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From tjreedy at udel.edu  Wed Jul 29 15:57:25 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Wed, 29 Jul 2009 15:57:25 -0400
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<ec96e1390907291108q13501e32hdecd99d4e017b932@mail.gmail.com>
Message-ID: <h4q9j5$bjf$1@ger.gmane.org>

Benjamin Kaplan wrote:
> On Wed, Jul 29, 2009 at 1:59 PM, dandi kain <dandi.kain at gmail.com> wrote:
>> Hello everybody,
>> I have just started learning Python.I heard its simple so I pick a
>> presentation [1] and tried to work on it.But when it comes to
>> underscores leading and trailing an object I dont understand any.I
>> look through the python manual also but that was not helping .I
>> searched some forums and I still dont have a clear picture.
>>
>> What is the functionality of __ or _ , leading or trailing an object ,
>> class ot function ? Is it just a naming convention to note special
>> functions and objects , or it really mean someting to Python ?
> 
> It's just a convention for the most part. A single leading underscore
> is used for "private" attributes. Two leading underscores will affect
> the code- it mangles the variable name so that you don't have to worry
> about the value being overwritten by a subclass. For instance
> """
> class Foo(object) :
>    def __init__(self) :
>        self.__bar = ''
> 
> foo = Foo()
> ""
> will store the attribute as foo._Foo__bar.
> 
> Also, the "magic methods"- the ones that are used for operations and
> built-in stuff, all have two leading and two trailing underscores.
> These are things like __add__ (+), __eq__ (=), __cmp__ (old way for
> comparisons), __len__ (len), __str__ (str), and so on.

For this last, see
http://docs.python.org/dev/py3k/reference/datamodel.html#special-method-names



From no.email at please.post  Wed Jul 29 16:05:36 2009
From: no.email at please.post (kj)
Date: Wed, 29 Jul 2009 20:05:36 +0000 (UTC)
Subject: How to "gunzip-iterate" over a file?
Message-ID: <h4qa2g$i5v$1@reader1.panix.com>




I need to iterate over the lines of *very* large (>1 GB) gzipped
files.  I would like to do this without having to read the full
compressed contents into memory so that I can apply zlib.decompress
to these contents.  I also would like to avoid having to gunzip
the file (i.e. creating an uncompressed version of the file in the
filesystem) prior to iterating over it.

Basically I'm looking for something that will give me the same
functionality as Perl's gzip IO layer, which looks like this (from
the documentation):

         use PerlIO::gzip;
         open FOO, "<:gzip", "file.gz" or die $!;
         print while <FOO>; # And it will be uncompressed...

What's the best way to achieve the same functionality in Python?

TIA!

kynn


From malc0de.encrypt at gmail.com  Wed Jul 29 16:21:56 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Wed, 29 Jul 2009 13:21:56 -0700 (PDT)
Subject: Does python have the capability for driver development ?
Message-ID: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>

hello there, I've a question :
I want to know does python have any capability for using Ring0 and
kernel functions for driver and device development stuff .
if there's such a feature it is very good, and if there something for
this kind that you know please refer me to some reference and show me
some snippet .

thanks

- Malc0de


From robert.kern at gmail.com  Wed Jul 29 16:22:43 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 29 Jul 2009 15:22:43 -0500
Subject: How to "gunzip-iterate" over a file?
In-Reply-To: <h4qa2g$i5v$1@reader1.panix.com>
References: <h4qa2g$i5v$1@reader1.panix.com>
Message-ID: <h4qb2j$fck$1@ger.gmane.org>

On 2009-07-29 15:05, kj wrote:
>
>
> I need to iterate over the lines of *very* large (>1 GB) gzipped
> files.  I would like to do this without having to read the full
> compressed contents into memory so that I can apply zlib.decompress
> to these contents.  I also would like to avoid having to gunzip
> the file (i.e. creating an uncompressed version of the file in the
> filesystem) prior to iterating over it.
>
> Basically I'm looking for something that will give me the same
> functionality as Perl's gzip IO layer, which looks like this (from
> the documentation):
>
>           use PerlIO::gzip;
>           open FOO, "<:gzip", "file.gz" or die $!;
>           print while<FOO>; # And it will be uncompressed...
>
> What's the best way to achieve the same functionality in Python?

http://docs.python.org/library/gzip

import gzip

f = gzip.open('filename.gz')
for line in f:
     print line
f.close()

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From npuloski at gmail.com  Wed Jul 29 16:23:33 2009
From: npuloski at gmail.com (Nanime Puloski)
Date: Wed, 29 Jul 2009 16:23:33 -0400
Subject: Differences Between Arrays and Matrices in Numpy
Message-ID: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>

What are some differences between arrays and matrices using the Numpy
library? When would I want to use arrays instead of matrices and vice
versa?


From pfeldman at verizon.net  Wed Jul 29 16:26:23 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Wed, 29 Jul 2009 13:26:23 -0700 (PDT)
Subject: delayed sys.exit?
Message-ID: <24726902.post@talk.nabble.com>


In the attached  http://www.nabble.com/file/p24726902/test.py test.py code,
it appears that additional statements execute after the call to sys.exit(0). 
I'll be grateful if anyone can shed light on why this is happening.  Below
is a copy of some sample I/O.  Note that in the last case I get additional
output after what should be the final error message.

In [126]: run test
Input a string: 1,2
[1, 2]

In [127]: run test
Input a string: 1-3
[1, 2, 3]

In [128]: run test
Input a string: 1,4,5-12
[1, 4, 5, 6, 7, 8, 9, 10, 11, 12]

In [129]: run test
Input a string: 0
ERROR: 0 is invalid; run numbers must be positive.
ERROR: '0' is not a valid run number.


-- 
View this message in context: http://www.nabble.com/delayed-sys.exit--tp24726902p24726902.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From james at agentultra.com  Wed Jul 29 16:33:11 2009
From: james at agentultra.com (J Kenneth King)
Date: Wed, 29 Jul 2009 16:33:11 -0400
Subject: escaping characters in filenames
References: <854osv7h2k.fsf@agentultra.com>
	<pan.2009.07.29.18.55.16.468000@nowhere.com>
Message-ID: <85ws5r5iwo.fsf@agentultra.com>

Nobody <nobody at nowhere.com> writes:

> On Wed, 29 Jul 2009 09:29:55 -0400, J Kenneth King wrote:
>
>> I wrote a script to process some files using another program.  One thing
>> I noticed was that both os.listdir() and os.path.walk() will return
>> unescaped file names (ie: "My File With Spaces & Stuff" instead of "My\
>> File\ With\ Spaces\ \&\ Stuff").  I haven't had much success finding a
>> module or recipe that escapes file names and was wondering if anyone
>> could point me in the right direction.
>> 
>> As an aside, the script is using subprocess.call() with the "shell=True"
>> parameter.  There isn't really a reason for doing it this way (was just
>> the fastest way to write it and get a prototype working).  I was
>> wondering if Popen objects were sensitive to unescaped names like the
>> shell.  I intend to refactor the function to use Popen objects at some
>> point and thought perhaps escaping file names may not be entirely
>> necessary.
>
> Note that subprocess.call() is nothing more than:
>
> 	def call(*popenargs, **kwargs):
> 	    return Popen(*popenargs, **kwargs).wait()
>
> plus a docstring. It accepts exactly the same arguments as Popen(), with
> the same semantics.
>
> If you want to run a command given a program and arguments, you
> should pass the command and arguments as a list, rather than trying to
> construct a string.
>
> On Windows the value of shell= is unrelated to whether the command is
> a list or a string; a list is always converted to string using the
> list2cmdline() function. Using shell=True simply prepends "cmd.exe /c " to
> the string (this allows you to omit the .exe/.bat/etc extension for
> extensions which are in %PATHEXT%).
>
> On Unix, a string is first converted to a single-element list, so if you
> use a string with shell=False, it will be treated as the name of an
> executable to be run without arguments, even if contains spaces, shell
> metacharacters etc.
>
> The most portable approach seems to be to always pass the command as a
> list, and to set shell=True on Windows and shell=False on Unix.
>
> The only reason to pass a command as a string is if you're getting a
> string from the user and you want it to be interpreted using the
> platform's standard shell (i.e. cmd.exe or /bin/sh). If you want it to be
> interpreted the same way regardless of platform, parse it into a
> list using shlex.split().

I understand; I think I was headed towards subprocess.Popen() either
way.  It seems to handle the problem I posted about.  And I got to learn
a little something on the way.  Thanks!

Only now there's a new problem in that the output of the program is
different if I run it from Popen than if I run it from the command line.
The program in question is 'pdftotext'.  More investigation to ensue.

Thanks again for the helpful post.


From robert.kern at gmail.com  Wed Jul 29 16:36:03 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 29 Jul 2009 15:36:03 -0500
Subject: Differences Between Arrays and Matrices in Numpy
In-Reply-To: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>
References: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>
Message-ID: <h4qbro$jl2$1@ger.gmane.org>

On 2009-07-29 15:23, Nanime Puloski wrote:
> What are some differences between arrays and matrices using the Numpy
> library? When would I want to use arrays instead of matrices and vice
> versa?

You will want to ask numpy questions on the numpy mailing list:

   http://www.scipy.org/Mailing_Lists

An overview of how the matrix subclass differs from ndarray, see the documentation:

   http://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects

Basically, I suggest that you just use regular arrays always. There is a 
syntactical convenience to matrix objects, but it does cause incompatibilities 
with the majority of code that is written for regular arrays. The convenience is 
usually not worth the cost.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From apt.shansen at gmail.com  Wed Jul 29 16:36:32 2009
From: apt.shansen at gmail.com (Stephen Hansen)
Date: Wed, 29 Jul 2009 13:36:32 -0700
Subject: delayed sys.exit?
In-Reply-To: <24726902.post@talk.nabble.com>
References: <24726902.post@talk.nabble.com>
Message-ID: <7a9c25c20907291336k5b4686c9sb410710967307907@mail.gmail.com>

>
> In the attached  http://www.nabble.com/file/p24726902/test.py test.py
> code,
> it appears that additional statements execute after the call to
> sys.exit(0).
> I'll be grateful if anyone can shed light on why this is happening.  Below
> is a copy of some sample I/O.  Note that in the last case I get additional
> output after what should be the final error message.
>

A bare "except:" catches ALL exceptions; including SystemExit which is
generated by
sys.exit. And KeyboardInterrupt, too. That's why its basically a bad
idea to use bare excepts unless you really, really, really need to.
Try 'except Exception' instead. SystemExit and such do not inherit
from Exception.

--S
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090729/89114fbe/attachment-0001.html>

From __peter__ at web.de  Wed Jul 29 16:40:13 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 29 Jul 2009 22:40:13 +0200
Subject: delayed sys.exit?
References: <mailman.3918.1248899186.8015.python-list@python.org>
Message-ID: <h4qc32$as8$02$1@news.t-online.com>

Dr. Phillip M. Feldman wrote:

> In the attached  http://www.nabble.com/file/p24726902/test.py test.py
> code, it appears that additional statements execute after the call to
> sys.exit(0).

>    try:
>       # If the conversion to int fails, nothing is appended to the list:
>       Runs.append(int(strs[i]))
>       if Runs[-1] <= 0:
>          print 'ERROR: ' + str(Runs[-i]) + \
>            ' is invalid; run numbers must be positive.'
>          sys.exit(0)
>    except:

sys.exit() works by raising a SystemExit exception which is caught by the 
bare except.

http://docs.python.org/library/sys.html#sys.exit
http://docs.python.org/library/exceptions.html#exceptions.SystemExit

As a general rule try to be as specific as possible when catching 
exceptions.

Peter



From python at mrabarnett.plus.com  Wed Jul 29 16:41:37 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Wed, 29 Jul 2009 21:41:37 +0100
Subject: delayed sys.exit?
In-Reply-To: <24726902.post@talk.nabble.com>
References: <24726902.post@talk.nabble.com>
Message-ID: <4A70B401.9040700@mrabarnett.plus.com>

Dr. Phillip M. Feldman wrote:
> In the attached  http://www.nabble.com/file/p24726902/test.py test.py code,
> it appears that additional statements execute after the call to sys.exit(0). 
> I'll be grateful if anyone can shed light on why this is happening.  Below
> is a copy of some sample I/O.  Note that in the last case I get additional
> output after what should be the final error message.
> 
> In [126]: run test
> Input a string: 1,2
> [1, 2]
> 
> In [127]: run test
> Input a string: 1-3
> [1, 2, 3]
> 
> In [128]: run test
> Input a string: 1,4,5-12
> [1, 4, 5, 6, 7, 8, 9, 10, 11, 12]
> 
> In [129]: run test
> Input a string: 0
> ERROR: 0 is invalid; run numbers must be positive.
> ERROR: '0' is not a valid run number.
> 
sys.exit raises an SystemExit exception, which then gets caught by the
bare 'except' of the enclosing try...except... statement.

A lot of things can raise an exception, which is why bare 'except's are
a bad idea; catch only those you expect.


From Russ.Davis at njpines.state.nj.us  Wed Jul 29 16:55:27 2009
From: Russ.Davis at njpines.state.nj.us (Russ Davis)
Date: Wed, 29 Jul 2009 16:55:27 -0400
Subject: IDLE Config Problems
Message-ID: <4A70801E.DEDA.009D.0@njpines.state.nj.us>

I am just getting started with Python and have installed v. 2.5.4  Idle version 1.2.4  I can't seem to get the idle to display text.  It seems as if the install went fine.  I start up the idle and the screen is blank.  No text.  It seems as if I can type on the screen but I just can't see the characters.   I go to the config menu and it bombs and brings up the Visual Studio debugger.  The computer that I am trying to install it on is a windows xp laptop serv pack 2.   I have a workstation here that I am using also with the same os and the idle works fine.  Any hints as to what might be interfering with the idle config.

Thanks

Russ

Russell Davis PP, AICP, GISP
GIS Administrator
State of New Jersey Pinelands Commission
Office of Land Use and Technology
GIS Laboratory
Po Box 7
New Lisbon, NJ 08064
Phone 609-894-7300
Fax 609-894-7330
russ.davis at njpines.state.nj.us



From __peter__ at web.de  Wed Jul 29 17:06:30 2009
From: __peter__ at web.de (Peter Otten)
Date: Wed, 29 Jul 2009 23:06:30 +0200
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <h4qdkb$2pm$00$1@news.t-online.com>

Martin wrote:

> I am trying to set the return value from a function to a name which I
> grab from the for loop. I can't work out how I can do this without
> using an if statement...
> 
> for f in var1_fn, var2_fn, var3_fn:
>     if f.split('.')[0] == 'var1':
>         var1 = call_some_function(f)
> .
>         .
>         .
>       etc
> 
>  Really I would like to remove the need for this if loop and I am sure
> there is a simple way I am missing?

Use dictionaries:

functions = {"var1": some_function, "var2": some_other_function, ...} 
return_values = {}

for arg in var1_fn, var2_fn, var3_fn:
    key = arg.split(".")[0]
    return_values[key] = functions[key](arg)

Peter



From martin.hellwig at dcuktec.org  Wed Jul 29 17:08:23 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Wed, 29 Jul 2009 22:08:23 +0100
Subject: simple splash screen?
In-Reply-To: <79954da5-a437-48a1-985b-88abe601d021@a37g2000prf.googlegroups.com>
References: <79a6c64f-af43-455f-a989-16dd6bb9e30e@a39g2000pre.googlegroups.com>
	<LYudnbbBM-OdD-3XnZ2dnUVZ8opi4p2d@bt.com>
	<79954da5-a437-48a1-985b-88abe601d021@a37g2000prf.googlegroups.com>
Message-ID: <se-dndtmZ63UJ-3XnZ2dnUVZ8n1i4p2d@bt.com>

NighterNet wrote:
<cut>
> Thanks it help. Sorry about that, I was just wander what kind of
> answer and if there are other methods to learn it.
> 
> Is there a way to position image to the center screen?

Yes there is, just start reading from here:
http://effbot.org/tkinterbook/

Though because Python 3 has done some module reorganisation/renaming, 
Tkinter is now called tkinter.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From deets at nospam.web.de  Wed Jul 29 17:11:49 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Wed, 29 Jul 2009 23:11:49 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
Message-ID: <7dbs8nF2br07nU1@mid.uni-berlin.de>

MalC0de schrieb:
> hello there, I've a question :
> I want to know does python have any capability for using Ring0 and
> kernel functions for driver and device development stuff .
> if there's such a feature it is very good, and if there something for
> this kind that you know please refer me to some reference and show me
> some snippet .

No, it can't do such things. At least it isn't embedded in the kernel - 
in theory that might be possible, but given the timing-constraints and 
concurrency-requirements, it's not really feasible.

Diez


From bearophileHUGS at lycos.com  Wed Jul 29 17:12:34 2009
From: bearophileHUGS at lycos.com (Bearophile)
Date: Wed, 29 Jul 2009 14:12:34 -0700 (PDT)
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <eefa9f4d-b763-41da-9be5-9caedc11ba63@d4g2000yqa.googlegroups.com>

Martin:
> for f in var1_fn, var2_fn, var3_fn:
> ? ? if f.split('.')[0] == 'var1':
> ? ? ? ? var1 = call_some_function(f)
> ? ? ? ? .
> ? ? ? ? .
> ? ? ? ? .
> ? ? ? etc

As usual I have big problems in understanding what you want to do.

Please, show an example of the contents of var1_fn, var2_fn, etc.

Generally you can create a dict:
results = {}

And then fill it with name-result pairs:
name = value.split('_')[0]
results[name] = some_function(value)

Bye,
bearophile


From andre.roberge at gmail.com  Wed Jul 29 17:18:52 2009
From: andre.roberge at gmail.com (=?ISO-8859-1?Q?Andr=E9?=)
Date: Wed, 29 Jul 2009 14:18:52 -0700 (PDT)
Subject: how to embed the python interpreter into web App (Mehndi, Sibtey)
References: <mailman.14496.1248881699.8014.python-list@python.org> 
	<mailman.3901.1248885631.8015.python-list@python.org>
Message-ID: <4c2f2ee0-1009-4dc7-8cd7-b38db43d83c7@o32g2000yqm.googlegroups.com>

On Jul 29, 1:11?pm, Ryniek90 <rynie... at gmail.com> wrote:
> > Hi All
>
> > I am trying to embed the python interpreter in to a web app but could
> > not get the way, any one can suggest me how to do this.
>
> > Thanks,
>
> > Sibtey Mehdi
>
> > This e-mail (and any attachments), is confidential and may be privileged. It may be read, copied and used only
> > by intended recipients. Unauthorized access to this e-mail (or attachments) and disclosure or copying of its
> > contents or any action taken in reliance on it is unlawful. Unintended recipients must notify the sender immediately
> > by e-mail/phone & delete it from their system without making any copies or disclosing it to a third person.
>
> Here's example:http://try-python.mired.org/
>
> Contact with author of that website/webapp.
>
> Good luck.

Or you can look at the code for Crunchy: http://code.google.com/p/crunchy

Note however that this will result in something that is not secure...
To quote the try-python site:

"My ISP (idiom.com) provides a sandbox inside a FreeBSD Jail..."

Andr?


From davea at ieee.org  Wed Jul 29 17:47:43 2009
From: davea at ieee.org (Dave Angel)
Date: Wed, 29 Jul 2009 17:47:43 -0400
Subject: set variable to looping index?
In-Reply-To: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <4A70C37F.2030709@ieee.org>

Martin wrote:
> Hi,
>
> I am trying to set the return value from a function to a name which I
> grab from the for loop. I can't work out how I can do this without
> using an if statement...
>
> for f in var1_fn, var2_fn, var3_fn:
>     if f.split('.')[0] == 'var1':
>         var1 = call_some_function(f)
> 	.
>         .
>         .
>       etc
>
>  Really I would like to remove the need for this if loop and I am sure
> there is a simple way I am missing?
>
> Many thanks
>
> Martin
>
>   

Is this a real problem, or is it a "programming puzzle"?   If it's the 
latter, maybe someone else can help.

But if it's a real problem, give us some context, and maybe we can 
figure out how to help.

If I took this fragment at face value, I'd simply replace it by:

var1 = call_some_function(var1_fn)
var2 = call_some_function(var2_fn)
var3 = call_some_function(var3_fn)


Is this fragment part of a function definition, or is it top-level?  Are 
there really exactly three var*_fn objects, or might there be an 
arbitrary number of them?   Do you want to tell us the types of these 
three objects?  Is there content really tied directly to their name?  
Did they get their values from literals, or were they computed at some 
other point?


DaveA


From rhodri at wildebst.demon.co.uk  Wed Jul 29 18:02:00 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Wed, 29 Jul 2009 23:02:00 +0100
Subject: set variable to looping index?
In-Reply-To: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
Message-ID: <op.uxunhmr1a8ncjz@gnudebst>

On Wed, 29 Jul 2009 19:56:28 +0100, Martin <mdekauwe at gmail.com> wrote:

> Hi,
>
> I am trying to set the return value from a function to a name which I
> grab from the for loop. I can't work out how I can do this without
> using an if statement...
>
> for f in var1_fn, var2_fn, var3_fn:
>     if f.split('.')[0] == 'var1':
>         var1 = call_some_function(f)
> 	.
>         .
>         .
>       etc
>
>  Really I would like to remove the need for this if loop and I am sure
> there is a simple way I am missing?

It's a little hard to tell what you actually want from your description,
but it looks like you're fighting the language unnecessarily here.  If
you have a sequence of functions that you want a sequence of results
out of, you should be thinking in terms of a sequence type.  A list,
in other words.

results = []
for f in fn1, fn2, fn3:
     results.append(f())


-- 
Rhodri James *-* Wildebeest Herder to the Masses


From nobody at nowhere.com  Wed Jul 29 18:21:27 2009
From: nobody at nowhere.com (Nobody)
Date: Wed, 29 Jul 2009 23:21:27 +0100
Subject: Differences Between Arrays and Matrices in Numpy
References: <mailman.3917.1248899015.8015.python-list@python.org>
Message-ID: <pan.2009.07.29.22.21.27.546000@nowhere.com>

On Wed, 29 Jul 2009 16:23:33 -0400, Nanime Puloski wrote:

> What are some differences between arrays and matrices using the Numpy
> library?

Matrices are always two-dimensional, as are slices of them. Matrices
override mulitplication and exponentiation to use matrix multiplication
rather than element-wise multiplication.

> When would I want to use arrays instead of matrices and vice
> versa?

Use a matrix if you want a matrix, i.e. a linear transformation.
Otherwise, use an array.



From mdekauwe at gmail.com  Wed Jul 29 18:29:30 2009
From: mdekauwe at gmail.com (Martin)
Date: Wed, 29 Jul 2009 15:29:30 -0700 (PDT)
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
Message-ID: <0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>

On Jul 29, 11:02?pm, "Rhodri James" <rho... at wildebst.demon.co.uk>
wrote:
> On Wed, 29 Jul 2009 19:56:28 +0100, Martin <mdeka... at gmail.com> wrote:
> > Hi,
>
> > I am trying to set the return value from a function to a name which I
> > grab from the for loop. I can't work out how I can do this without
> > using an if statement...
>
> > for f in var1_fn, var2_fn, var3_fn:
> > ? ? if f.split('.')[0] == 'var1':
> > ? ? ? ? var1 = call_some_function(f)
> > ? ?.
> > ? ? ? ? .
> > ? ? ? ? .
> > ? ? ? etc
>
> > ?Really I would like to remove the need for this if loop and I am sure
> > there is a simple way I am missing?
>
> It's a little hard to tell what you actually want from your description,
> but it looks like you're fighting the language unnecessarily here. ?If
> you have a sequence of functions that you want a sequence of results
> out of, you should be thinking in terms of a sequence type. ?A list,
> in other words.
>
> results = []
> for f in fn1, fn2, fn3:
> ? ? ?results.append(f())
>
> --
> Rhodri James *-* Wildebeest Herder to the Masses

Hi all,

Thanks and apologises I wasn't trying to be cryptic, like all things
when I wrote it I thought it was quite transparent.

All I was trying to do was call a function and return the result to an
a variable. I could admittedly of just done...

var1 = some_function(var1_fn)
var2 = some_function(var2_fn)
var3 = some_function(var3_fn)

where var1_fn, var2_fn, var3_fn are just filenames, e.g. var1_fn =
'x.txt'. But I figured I would try and make it slightly more generic
whilst I was at it, hence my attempt to use the filenames to create
the variable names (hence the loop). I will as suggested try the
dictionary option. I appreciate all the suggestions.

Thanks

Martin


From nick at craig-wood.com  Wed Jul 29 18:29:56 2009
From: nick at craig-wood.com (Nick Craig-Wood)
Date: Wed, 29 Jul 2009 17:29:56 -0500
Subject: Does python have the capability for driver development ?
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<7dbs8nF2br07nU1@mid.uni-berlin.de>
Message-ID: <slrnh71g6g.djc.nick@irishsea.home.craig-wood.com>

Diez B. Roggisch <deets at nospam.web.de> wrote:
>  MalC0de schrieb:
> > hello there, I've a question :
> > I want to know does python have any capability for using Ring0 and
> > kernel functions for driver and device development stuff .
> > if there's such a feature it is very good, and if there something for
> > this kind that you know please refer me to some reference and show me
> > some snippet .
> 
>  No, it can't do such things. At least it isn't embedded in the kernel - 
>  in theory that might be possible, but given the timing-constraints and 
>  concurrency-requirements, it's not really feasible.

You can write FUSE (file systems in userspace) drivers in python I believe.
Not the same as running in ring0 but in most senses a kernel driver...

-- 
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick


From pavlovevidence at gmail.com  Wed Jul 29 18:55:26 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 29 Jul 2009 15:55:26 -0700 (PDT)
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com> 
	<m2fxcfefu2.fsf@cs.uu.nl>
Message-ID: <8cb1ba65-be71-49b7-8955-54c17f351a40@w6g2000yqw.googlegroups.com>

On Jul 29, 7:14?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
> >>>>> Carl Banks <pavlovevide... at gmail.com> (CB) wrote:
> >CB> On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
> >>> I'm looking to run a process with a limit of 3 instances, but each
> >>> execution is over a crontab interval. I've been investigating the
> >>> threading module and using daemons to limit active thread objects, but
> >>> I'm not very successful at grasping the documentation.
>
> >>> Is it possible to do what I'm trying to do and if so anyone know of a
> >>> useful example to get started?
> >CB> It seems like you want to limit the number of processes to three; the
> >CB> threading module won't help you there because it deals with threads
> >CB> within a single process.
> >CB> What I'd do is to simply run the system ps to see how many processes
> >CB> are running (ps is pretty versatile on most systems and can find
> >CB> specifically targeted processes like you program), and exit if there
> >CB> are already three.
>
> That will surely run into some race conditions.

What, the OS might not have gotten around to update the process table
to include a process started minutes ago?  (He said he was starting
the processes over crontab intervals, not that he communicated what he
wanted well.)


Carl Banks


From zuo at chopin.edu.pl  Wed Jul 29 18:57:02 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 00:57:02 +0200
Subject: set variable to looping index?
In-Reply-To: <0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
	<0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
Message-ID: <op.uxup1cxjfvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 <mdekauwe at gmail.com> wrote:

> All I was trying to do was call a function and return the result to an
> a variable. I could admittedly of just done...
>
> var1 = some_function(var1_fn)
> var2 = some_function(var2_fn)
> var3 = some_function(var3_fn)
>
> where var1_fn, var2_fn, var3_fn are just filenames, e.g. var1_fn =
> 'x.txt'. But I figured I would try and make it slightly more generic
> whilst I was at it, hence my attempt to use the filenames to create
> the variable names (hence the loop).

Hi,

Then you could also consider using simply lists:

filenames = p'foo', 'bar', baz']
results = []
for name in filenames:
     results.append(some_function(name))

If filenames were generated according to a particular pattern, you can
mimic that pattern and generate filenames list using
list-comprehension, e.g.:

filenames = ['file{nr}.txt'.format(nr=nr) for nr in range(13)]

Chreers,

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From zuo at chopin.edu.pl  Wed Jul 29 19:03:33 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 01:03:33 +0200
Subject: set variable to looping index?
In-Reply-To: <op.uxup1cxjfvx12t@jerzozwiesz.home.aster.pl>
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
	<0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
	<op.uxup1cxjfvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <op.uxuqb7a6fvx12t@jerzozwiesz.home.aster.pl>

Me wrote:

> filenames = p'foo', 'bar', baz']

Sorry, should be of course:

filenames = ['foo', 'bar', baz']

*j
-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From mdekauwe at gmail.com  Wed Jul 29 19:04:59 2009
From: mdekauwe at gmail.com (Martin)
Date: Wed, 29 Jul 2009 16:04:59 -0700 (PDT)
Subject: set variable to looping index?
References: <7ba88464-d33a-49e3-8263-459edfc5f9aa@c14g2000yqm.googlegroups.com>
	<mailman.3924.1248904929.8015.python-list@python.org>
	<0832103a-f0b4-4bd7-a423-a40884b973dc@o32g2000yqm.googlegroups.com>
	<mailman.3925.1248908229.8015.python-list@python.org>
Message-ID: <a0c47f56-6259-4c32-8c25-7efb93dddb08@32g2000yqj.googlegroups.com>

On Jul 29, 11:57?pm, "Jan Kaliszewski" <z... at chopin.edu.pl> wrote:
> 30-07-2009 <mdeka... at gmail.com> wrote:
> > All I was trying to do was call a function and return the result to an
> > a variable. I could admittedly of just done...
>
> > var1 = some_function(var1_fn)
> > var2 = some_function(var2_fn)
> > var3 = some_function(var3_fn)
>
> > where var1_fn, var2_fn, var3_fn are just filenames, e.g. var1_fn =
> > 'x.txt'. But I figured I would try and make it slightly more generic
> > whilst I was at it, hence my attempt to use the filenames to create
> > the variable names (hence the loop).
>
> Hi,
>
> Then you could also consider using simply lists:
>
> filenames = p'foo', 'bar', baz']
> results = []
> for name in filenames:
> ? ? ?results.append(some_function(name))
>
> If filenames were generated according to a particular pattern, you can
> mimic that pattern and generate filenames list using
> list-comprehension, e.g.:
>
> filenames = ['file{nr}.txt'.format(nr=nr) for nr in range(13)]
>
> Chreers,
>
> *j
>
> --
> Jan Kaliszewski (zuo) <z... at chopin.edu.pl>

I guess I wanted to keep the function returns in separate arrays in
this case, hence my attempt to make variable names based on the
filenames.

Thanks

Martin


From martin.hellwig at dcuktec.org  Wed Jul 29 19:05:04 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 00:05:04 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
Message-ID: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>

MalC0de wrote:
> hello there, I've a question :
> I want to know does python have any capability for using Ring0 and
> kernel functions for driver and device development stuff .
> if there's such a feature it is very good, and if there something for
> this kind that you know please refer me to some reference and show me
> some snippet .
> 
> thanks
> 
> - Malc0de

Python is interpreted, so the first requirement would be that the 
interpreter (the python VM to be more precise) would run in the kernel 
or that there is a way for the interpreter to delegate operations to 
kernel restricted operations. Most notably access to the memory location 
of the hardware you want to write a driver for and possibly also a way 
to pass through a callback function for triggered  interrupt coming from 
the hardware.

So technically speaking it shouldn't be impossible. And there is perhaps 
something to say for being able to write drivers in a readable/easy 
programming language however I am afraid that if such a beast would be 
made that it would remain an academical exercise only due to performance 
constraints.

Though I would love to play around with a system where the kernel is 
essentially only a python interpreter, with full raw access to the hardware.

But creating such a thing requires more talent and understanding than 
currently (and probably ever) in my possession.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From cjw at ncf.ca  Wed Jul 29 19:27:41 2009
From: cjw at ncf.ca (Colin J. Williams)
Date: Wed, 29 Jul 2009 19:27:41 -0400
Subject: Differences Between Arrays and Matrices in Numpy
In-Reply-To: <mailman.3919.1248899788.8015.python-list@python.org>
References: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>
	<mailman.3919.1248899788.8015.python-list@python.org>
Message-ID: <h4qltf$9i3$1@theodyn.ncf.ca>

Robert Kern wrote:
> On 2009-07-29 15:23, Nanime Puloski wrote:
>> What are some differences between arrays and matrices using the Numpy
>> library? When would I want to use arrays instead of matrices and vice
>> versa?
> 
> You will want to ask numpy questions on the numpy mailing list:
> 
>   http://www.scipy.org/Mailing_Lists
> 
> An overview of how the matrix subclass differs from ndarray, see the 
> documentation:
> 
>   
> http://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects 
> 
> 
> Basically, I suggest that you just use regular arrays always. There is a 
> syntactical convenience to matrix objects, but it does cause 
> incompatibilities with the majority of code that is written for regular 
> arrays. The convenience is usually not worth the cost.
> 

Numpy's arrays can have any dimensionality, whereas 
matrices[http://en.wikipedia.org/wiki/Matrix_%28mathematics%29], typically 
have two.  A single column can represent a vector or a single row can 
represent a transposed vector.

Does the additional cost arise because the commonly used procedures are 
accessed through numpy's array?

Colin W.



From rwanderley at rsw.digi.com.br  Wed Jul 29 19:30:21 2009
From: rwanderley at rsw.digi.com.br (Rodrigo S Wanderley)
Date: Wed, 29 Jul 2009 20:30:21 -0300
Subject: Does python have the capability for driver development ?
In-Reply-To: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com> (Martin P. Hellwig's
	message of "Thu, 30 Jul 2009 00:05:04 +0100")
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
Message-ID: <87skgf83ua.fsf@rsw.digi.com.br>

"Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:

> Python is interpreted, so the first requirement would be that the
> interpreter (the python VM to be more precise) would run in the kernel
> or that there is a way for the interpreter to delegate operations to
> kernel restricted operations. Most notably access to the memory
> location of the hardware you want to write a driver for and possibly
> also a way to pass through a callback function for triggered
> interrupt coming from the hardware.
>
> So technically speaking it shouldn't be impossible. And there is
> perhaps something to say for being able to write drivers in a
> readable/easy programming language however I am afraid that if such a
> beast would be made that it would remain an academical exercise only
> due to performance constraints.

What about user level device drivers? Think the Python VM could
communicate with the driver through the user space API.  Is there a
Python module for that?

-- 
Rodrigo S. Wanderley <rwanderley at rsw.digi.com.br>
  -- Blog: http://rsw.digi.com.br


From david.lyon at preisshare.net  Wed Jul 29 19:33:01 2009
From: david.lyon at preisshare.net (David Lyon)
Date: Wed, 29 Jul 2009 19:33:01 -0400
Subject: Does python have the capability for driver development
	=?UTF-8?Q?=3F?=
In-Reply-To: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
Message-ID: <bbda6d96cb07cc681061ed765c96b13c@preisshare.net>

 MalC0de wrote:
> hello there, I've a question :
> I want to know does python have any capability for using Ring0 and
> kernel functions for driver and device development stuff .
> if there's such a feature it is very good, and if there something for
> this kind that you know please refer me to some reference and show me
> some snippet .

What operating system are you talking about?

Most device drivers run at ring 3 (or lower) and not zero. This way if
there
is a driver crash the whole operating system doesn't freeze.

Python is generally considered a high-level language. If you want
to play around with drivers.. usb serial.. etc do it at a python
level through the existing device drivers.

imho the performance of interpreted python isn't compatible with
writing block-mode device drivers (hard-disks) and so forth.

What hardware do you have that you need to write a device driver
for ? Isn't there a device driver available already? or do you
mean just a device controller?

David





From robert.kern at gmail.com  Wed Jul 29 19:42:05 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Wed, 29 Jul 2009 18:42:05 -0500
Subject: Differences Between Arrays and Matrices in Numpy
In-Reply-To: <h4qltf$9i3$1@theodyn.ncf.ca>
References: <d785f9cc0907291323s3cd28438ucfd55e3b4e749f40@mail.gmail.com>	<mailman.3919.1248899788.8015.python-list@python.org>
	<h4qltf$9i3$1@theodyn.ncf.ca>
Message-ID: <h4qmof$j58$1@ger.gmane.org>

On 2009-07-29 18:27, Colin J. Williams wrote:
> Robert Kern wrote:
>> On 2009-07-29 15:23, Nanime Puloski wrote:
>>> What are some differences between arrays and matrices using the Numpy
>>> library? When would I want to use arrays instead of matrices and vice
>>> versa?
>>
>> You will want to ask numpy questions on the numpy mailing list:
>>
>> http://www.scipy.org/Mailing_Lists
>>
>> An overview of how the matrix subclass differs from ndarray, see the
>> documentation:
>>
>> http://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects
>>
>>
>> Basically, I suggest that you just use regular arrays always. There is
>> a syntactical convenience to matrix objects, but it does cause
>> incompatibilities with the majority of code that is written for
>> regular arrays. The convenience is usually not worth the cost.
>
> Numpy's arrays can have any dimensionality, whereas
> matrices[http://en.wikipedia.org/wiki/Matrix_%28mathematics%29],
> typically have two. A single column can represent a vector or a single
> row can represent a transposed vector.
>
> Does the additional cost arise because the commonly used procedures are
> accessed through numpy's array?

Most functions are written to expect that its inputs behave like ndarrays; e.g. 
a*b is elementwise multiplication rather than matrix multiplication. When you 
use the matrix subclass, you are basically confining yourself to a smallish 
ghetto of functions that knows how to deal with matrix semantics. That's a huge 
cost compared to the relatively small syntactic cost of having to write dot(a,b) 
instead of (a*b).

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From ben+python at benfinney.id.au  Wed Jul 29 19:42:35 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 30 Jul 2009 09:42:35 +1000
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <87ljm72h04.fsf@benfinney.id.au>

dandi kain <dandi.kain at gmail.com> writes:

> What is the functionality of __ or _ , leading or trailing an object ,
> class ot function ?

There is no change in functionality. It has some slight effects on
import, but as a beginner you shouldn't need to worry about that.

> Is it just a naming convention to note special functions and objects ,
> or it really mean someting to Python ?

Both. It's a strongly-adhered-to naming convention, as an indicator to
the reader how that name should be used.

    foo      Ordinary name, part of public interface
    _foo     Ordinary name, part of internal-only interface
    __foo    Ordinary name, but will be mangled (this style used rarely)
    __foo__  Name which is used in a special way by Python

There's no change in the objects themselves; the underscores rather
indicate how those names are expected to be accessed.

-- 
 \         ?Pinky, are you pondering what I'm pondering?? ?I think so, |
  `\   Brain, but Tuesday Weld isn't a complete sentence.? ?_Pinky and |
_o__)                                                       The Brain_ |
Ben Finney



From martin.hellwig at dcuktec.org  Wed Jul 29 19:44:41 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 00:44:41 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <87skgf83ua.fsf@rsw.digi.com.br>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<87skgf83ua.fsf@rsw.digi.com.br>
Message-ID: <4A70DEE9.1060105@dcuktec.org>

Rodrigo S Wanderley wrote:
> <cut>
> What about user level device drivers? Think the Python VM could
> communicate with the driver through the user space API.  Is there a
> Python module for that?
>
>   
Sure why not?
Look for example to libusb, which provides a userspace environment and 
pyusb which uses that and provides an interface to Python.

-- 
MPH



From nyamatongwe+thunder at gmail.com  Wed Jul 29 19:55:34 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Wed, 29 Jul 2009 23:55:34 GMT
Subject: No PyPI search for 3.x compatible packages
Message-ID: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>

   There appears to be no way to search PyPI for packages that are
compatible with Python 3.x. There are classifiers for 'Programming
Language' including 'Programming Language :: Python :: 3' but that seems
to be for implementation language since there are so many packages that
specify C. There are a total of 109 packages classified with Python ::
[3, 3.0, 3.1] out of a total of 4829 packages.
http://pypi.python.org/pypi?:action=browse&show=all&c=214&c=533

   The search box appears to search for any word entered so a search
like "xml 3.0" or "xml AND 3.0" does not help.

   Some packages include version information in the Py Version column of
their download lists or embedded in the download file names. Projects
are often constrained to a particular set of Python versions so need to
choose packages that will work with those versions. It would be helpful
if PyPI made this information more visible and searchable.

   Neil


From malc0de.encrypt at gmail.com  Wed Jul 29 20:19:42 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Wed, 29 Jul 2009 17:19:42 -0700 (PDT)
Subject: Does python have the capability for driver development ?
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<87skgf83ua.fsf@rsw.digi.com.br> 
	<mailman.3929.1248911448.8015.python-list@python.org>
Message-ID: <94abbddc-dac7-4215-84d1-d4eb3f82724d@h21g2000yqa.googlegroups.com>

actually I mean driver programming under Windows operating system, if
you know, there's A kit name DDK available at microsoft's website for
developing device drivers under C / C++ environment, now i'm working
with this kind of toolkit, but when I started programming with Python,
I saw this is very good and easy to develop application in all aspects
of a programmer or customer .
I love python cuze I can write every application i want, it's easy and
it's very robust, But i thought if there's any available toolkit like
Microsoft DDK which can program driver under windows but based on
python it's very good and well, I don't know it's the lack of python
or interpreter concept but cuze of the extensibility of python if such
a good feature can be added to python it will be good enough.
actually I want to write device drivers in Ring0 mode or kernel
mode ...
please introduce me some resource for system programming, I know that
python is very well at system programming level.
thanks

- Malc0de


From wuwei23 at gmail.com  Wed Jul 29 20:24:03 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 29 Jul 2009 17:24:03 -0700 (PDT)
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <11942b01-07b4-44d9-9be5-92868493b706@g1g2000pra.googlegroups.com>

On Jul 30, 3:59?am, dandi kain <dandi.k... at gmail.com> wrote:
> What is the functionality of __ or _ , leading or trailing an object ,
> class ot function ? Is it just a naming convention to note special
> functions and objects , or it really mean someting to Python ?

I think everyone else has covered what you need to know, but there's
still one remaining pseudo-convention you might see in Python code,
and that's using _ as a label to indicate that you don't care about
the value it holds.

Overly simplistic example:

data_set = [('gold','junk'),('gold','junk'),...]

for keep, _ in data_set:
    ...

It's a convenient way of not having to come up with a label for
something you're not going to use, although arguably you get the same
effect with names like 'dummy', 'ignore' etc. Not everyone agrees with
this usage but you _will_ see it in use in other people's code, so it
helps to have a heads up.


From marcusw at cox.net  Wed Jul 29 20:24:16 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Wed, 29 Jul 2009 20:24:16 -0400
Subject: Does python have the capability for driver development ?
In-Reply-To: <mailman.3929.1248911448.8015.python-list@python.org>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<87skgf83ua.fsf@rsw.digi.com.br>
	<mailman.3929.1248911448.8015.python-list@python.org>
Message-ID: <h4qp7u$15od$1@adenine.netfront.net>

On 7/29/2009 7:44 PM, Martin P. Hellwig wrote:
> Rodrigo S Wanderley wrote:
>> <cut>
>> What about user level device drivers? Think the Python VM could
>> communicate with the driver through the user space API.  Is there a
>> Python module for that?
>>
>>   
> Sure why not?
> Look for example to libusb, which provides a userspace environment and 
> pyusb which uses that and provides an interface to Python.
> 
iicr pyusb uses a c interface to libusb, not python...

Marcus


From http  Wed Jul 29 21:04:47 2009
From: http (Paul Rubin)
Date: 29 Jul 2009 18:04:47 -0700
Subject: How to "gunzip-iterate" over a file?
References: <h4qa2g$i5v$1@reader1.panix.com>
	<mailman.3916.1248898979.8015.python-list@python.org>
Message-ID: <7x8wi7j80g.fsf@ruckus.brouhaha.com>

Robert Kern <robert.kern at gmail.com> writes:
> f = gzip.open('filename.gz')
> for line in f:
>      print line

or use f.read(nbytes) to read n uncompressed bytes from f.  Note that
the standard iterator (which iterates over lines) can potentially
consume an unbounded amount of memory if the file contains no newlines.


From greg at cosc.canterbury.ac.nz  Wed Jul 29 21:09:14 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Thu, 30 Jul 2009 13:09:14 +1200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <mailman.3879.1248854780.8015.python-list@python.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<200907281035.48713.hendrik@microcorp.co.za>	<4A6F1506.9030207@mrabarnett.plus.com>
	<mailman.3879.1248854780.8015.python-list@python.org>
Message-ID: <7dca4iF2bgbn5U1@mid.individual.net>

Hendrik van Rooyen wrote:

> And if code is data, where is Pythons ALTER statement?

class Duck:

   def quack(self):
     print "Quack!"

def moo():
   print "Moo!"

def ALTER(obj, name, TO_PROCEED_TO):
   setattr(obj, name, TO_PROCEED_TO)

d = Duck()
ALTER(d, 'quack', TO_PROCEED_TO = moo)
d.quack()

-- 
Greg


From clp2 at rebertia.com  Wed Jul 29 21:21:32 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 18:21:32 -0700
Subject: Working with platform.system()
In-Reply-To: <9a5b5be90907290610t1868ef07p20a5c2bdc3404ab8@mail.gmail.com>
References: <9a5b5be90907290610t1868ef07p20a5c2bdc3404ab8@mail.gmail.com>
Message-ID: <50697b2c0907291821l54f30d99q44df2a9188a917f0@mail.gmail.com>

On Wed, Jul 29, 2009 at 6:10 AM, v1d4l0k4<v1d4l0k4 at gmail.com> wrote:
> Hi!
>
> I want to know how I can get different expected return values by
> platform.system() method. I want to sniff some systems (Linux, Windows, Mac,
> BSD, Solaris) and I don't know how I can check them correctly. Could you
> give me some expected return values that you know?

On my Mac, I get "Darwin".

You should file a bug in the docs after compiling the results, to help
future users.

Cheers,
Chris
-- 
http://blog.rebertia.com


From draghuram at gmail.com  Wed Jul 29 23:00:57 2009
From: draghuram at gmail.com (Raghuram Devarakonda)
Date: Wed, 29 Jul 2009 20:00:57 -0700 (PDT)
Subject: Connecting multiple test cases in a sort of pipe
Message-ID: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>


Hi,

I have three functions - create(), list(), and delete(). create()
creates a new name in the file system hierarchy while list() displays
all such created names and delete() removes them. I would like to
write test cases for each of these functions, say, test_create() ,
test_list(), and test_delete() using the unittest module. It easily
follows that test_list() and test_delete() will need to know the exact
name that was created in test_create() in order to properly validate
list() and delete(). One option is for test_create() to always use a
hard coded name but unfortunately this is not feasible.

Another way would be for test_create() to pass the new name down to
the next test case test_list() which would do the same and pass the
name down to test_delete(). In other words, the requirement is to
connect all three test cases in a kind of pipe. This facility is
obviously not currently present in the unittest module and nor does it
seem to be available in other frameworks (such as py.test and nose, I
only skimmed the feature list).

I am thinking of implementing this feature on top of unittest.TestCase
and would like to know what others think of the idea. Is there a
framework that has similar feature? Or perhaps, given my requirement
as stated above, is there some alternate way of implementing it? I
greatly appreciate any feed back.

Thanks,
Raghu




From rt8396 at gmail.com  Wed Jul 29 23:06:33 2009
From: rt8396 at gmail.com (r)
Date: Wed, 29 Jul 2009 20:06:33 -0700 (PDT)
Subject: Confessions of a Python fanboy
Message-ID: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>


Hello fellow Pythonista's it's nice to be back after such a long
hiatus. I have recently realized my  blind love affair with Python was
just that. I must admit there are better ways to program. Like your
first lay, your first programing language can leave an indelible mark
on you, but like all young chaps, the passion for programming has
sweep me away into vast new orgies of programming bliss. (ig ,little
head guides the big one.)

My adventures in Ruby.
an autobyography by rt8396

After breaking free from the wild love affair i had with Python, a new
day had dawned. I dried my eyes and soon discovered the Ruby language
(not by choice however) --now don't worry fellow Pythonistas, i am
still on your side (mostly)  -- but i now realize Ruby has some good
things going for it. For instance...

1.) No need to use "()" to call a function with no arguments.
Python --> "obj.m2().m3()" --ugly
  Ruby --> "obj.m1.m2.m3"  -- sweeet!
Man, i must admit i really like this, and your code will look so much
cleaner.

2.) the .each method
container.each{|localVar| block}
This method can really cleanup some ugly for loops, although i really
like the readability of for loops.

3.) true OOP
Now before you go and get all "huffy" over this statement, hear me
out. Python is the best language in the world. But it damn sure has
some warts! "len(this)" instead of "obj.length" max(that) instead of
[1,2,3,4,5].max(). You know what i am talking about here people. We
all get complacent and It seems easier to just cope with these
problems instead of fighting for change. But look at the French,  WHAT
THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!

As for the rest of Ruby, i am not impressed. The redundant usage of
"end" over indention perplexes me. The Perlish feel of "require" and
the horrifically cryptic idioms of Ruby regular expressions. The
"puts" and "gets" seem childish and the math class does not even have
a degrees or radians function!

Anyway, i thought i would get this off my chest and catch up with old
friends in the meantime. We can all make Python the perfect language
it needs to be, but it ain't gonna be easy!
Thank you all

PS stay tuned for more from this series....




From rt8396 at gmail.com  Wed Jul 29 23:43:58 2009
From: rt8396 at gmail.com (r)
Date: Wed, 29 Jul 2009 20:43:58 -0700 (PDT)
Subject: IDLE Config Problems
References: <mailman.3922.1248902818.8015.python-list@python.org>
Message-ID: <37c1f7fa-8008-41b0-b2c4-d9c1e5288e2e@v20g2000yqm.googlegroups.com>

On Jul 29, 3:55?pm, "Russ Davis" <Russ.Da... at njpines.state.nj.us>
wrote:
> I am just getting started with Python and have installed v. 2.5.4 ?Idle version 1.2.4 ?I can't seem to get the idle to display text. ?It seems as if the install went fine. ?I start up the idle and the screen is blank. ?No text. ?It seems as if I can type on the screen but I just can't see the characters. ? I go to the config menu and it bombs and brings up the Visual Studio debugger. ?The computer that I am trying to install it on is a windows xp laptop serv pack 2. ? I have a workstation here that I am using also with the same os and the idle works fine. ?Any hints as to what might be interfering with the idle config.
>

just spit balling here, but have you tried a un-install, re-install

""" Bad things can happen to good installers """


From darkneter at gmail.com  Wed Jul 29 23:52:06 2009
From: darkneter at gmail.com (NighterNet)
Date: Wed, 29 Jul 2009 20:52:06 -0700 (PDT)
Subject: socket send
Message-ID: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>

I am trying to figure out how to send text or byte in python 3.1. I am
trying to send data to flash socket to get there. I am not sure how to
work it.

buff= 'id=' , self.id , ':balive=False\n'
clientSock.send(buff);


From wuwei23 at gmail.com  Thu Jul 30 00:04:27 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 29 Jul 2009 21:04:27 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>

On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.

How do you distinguish between calling a method with no arguments, and
getting access to the method object itself (because it _is_ an object,
y'know, it's OO all the way down...)?

> 2.) the .each method
> container.each{|localVar| block}
> This method can really cleanup some ugly for loops, although i really
> like the readability of for loops.

map(lambda localVar: <block>, sequence)

or:

def usefully_named_func(var):
    <block>
    return var

transformed = [usefully_named_func(v) for v in sequence]

> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max().

As the Zen says: '[P]racticality beats purity'. Personally, I'm not
sure how a handful of convenient built-in functions make a language in
which _everything is an object_ somehow "false" OO.

If you're really that concerned with writing "true" OO (for some
wildly variable value of "true"), there's nothing stopping you from
doing so now:

    obj.__len__()

With max(), this is a built-in that takes _any_ iterable and an
optional key function, and returns the highest value as per the key.
This means that _every_ iterable object - as _well_ as every object
that supports enough of the iterator protocol - can be handed to max()
and a result obtained. So at best, I just need to make sure my new
sequence-type provides the iterator protocol and viola, it works with
max() without me having to hand-code a .max() that's specialised for
my new type, and without Python forcing me to have a complex
inheritance chain just to make sure I include the right
MaxableSequence ancestor to inherit the right .max().

> PS stay tuned for more from this series....

Is this going to be more of you telling us - without any apparent
irony whatsoever - how Ruby has some valid points after all your
vilification last year when we said the same to you?  If so, where can
I sign up?!

(You should consider trading guest spot posts with Xah Lee on your
respective blogs. You both have a very similar approach to programming
& programming languages and I think the synergy would be amazing to
see.)


From pdlemper at earthlink.net  Thu Jul 30 00:24:11 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Wed, 29 Jul 2009 23:24:11 -0500
Subject: gamma approximation : what is module cmath and where is it located ?
Message-ID: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>

The following numerical approximation for Euler's Gamma function
is found in http://en.wikipedia.org/wiki/Lanczos_approximation

from cmath import *
 
# Coefficients used by the GNU Scientific Library
g = 7
p = [0.99999999999980993, 676.5203681218851, -1259.1392167224028,
     771.32342877765313, -176.61502916214059, 12.507343278686905,
     -0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7]
 
def gamma(z):
    z = complex(z)
    # Reflection formula
    if z.real < 0.5:
        return pi / (sin(pi*z)*gamma(1-z))
    else:
        z -= 1
        x = p[0]
        for i in range(1, g+2):
            x += p[i]/(z+i)
        t = z + g + 0.5
        return sqrt(2*pi) * t**(z+0.5) * exp(-t) * x


This works in Python 3.0    
  
But I can't figure out where it gets "cmath".    Searching the Python 
directory reveals no more than a test_cmath.  The only cmath I can find
is a header file in another directory  turboc++\Borland\include\

dir(cmath) reveals 23 functions overlapping the 37 functions of
the math module.

What is cmath, where did it come from and how does it differ from
the standard math module  ?

Dave WB3DWE
                                   I saw the number 4 in silver,  Guido
                                     (apologies to Wm Carlos Williams)


From clp2 at rebertia.com  Thu Jul 30 00:27:20 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 21:27:20 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <50697b2c0907292127l98ff61aief7f7205b5b5ca9@mail.gmail.com>

On Wed, Jul 29, 2009 at 9:04 PM, alex23<wuwei23 at gmail.com> wrote:
> On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
>> 1.) No need to use "()" to call a function with no arguments.
>> Python --> "obj.m2().m3()" --ugly
>> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
>> Man, i must admit i really like this, and your code will look so much
>> cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?

IIRC from the Pickaxe, to get at a method object, you call a method on
the object whose specific job it is to return method objects.
Unsurprisingly, this method is itself named "method". So:

foo.bar #calls the "bar" method on foo
foo.method(:bar) #returns the method "bar" of foo, as an object

Cheers,
Chris
-- 
http://blog.rebertia.com


From clp2 at rebertia.com  Thu Jul 30 00:34:07 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 21:34:07 -0700
Subject: gamma approximation : what is module cmath and where is it 
	located ?
In-Reply-To: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <50697b2c0907292134p594105fag2bf99e0b5e14e35c@mail.gmail.com>

On Wed, Jul 29, 2009 at 9:24 PM, <pdlemper at earthlink.net> wrote:
<snip>
> But I can't figure out where it gets "cmath". ? ?Searching the Python
> directory reveals no more than a test_cmath. ?The only cmath I can find
> is a header file in another directory ?turboc++\Borland\include\
>
> dir(cmath) reveals 23 functions overlapping the 37 functions of
> the math module.
>
> What is cmath, where did it come from and how does it differ from
> the standard math module ??

It's a module in the standard library:
http://docs.python.org/library/cmath.html

The difference is that it handles complex numbers, whereas the plain
"math" module doesn't.
I would guess the reason there are separate modules is for
performance, so as to avoid having to dispatch on type at runtime. But
this is only a guess.

Cheers,
Chris
-- 
http://blog.rebertia.com


From pavlovevidence at gmail.com  Thu Jul 30 00:36:31 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 29 Jul 2009 21:36:31 -0700 (PDT)
Subject: gamma approximation : what is module cmath and where is it 
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>

On Jul 29, 9:24?pm, pdlem... at earthlink.net wrote:
> What is cmath, where did it come from and how does it differ from
> the standard math module ??

What happened when you did a keyword search for "cmath" in the Python
library documentation?

What happened when you entered "python cmath" in Google?


Carl Banks


From pavlovevidence at gmail.com  Thu Jul 30 00:43:47 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Wed, 29 Jul 2009 21:43:47 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <ab5cb173-7069-4bab-b693-70cfd145c3f4@h11g2000yqb.googlegroups.com>

On Jul 29, 9:04?pm, alex23 <wuwe... at gmail.com> wrote:
> On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
>
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?
>
> > 2.) the .each method
> > container.each{|localVar| block}
> > This method can really cleanup some ugly for loops, although i really
> > like the readability of for loops.
>
> map(lambda localVar: <block>, sequence)
>
> or:
>
> def usefully_named_func(var):
> ? ? <block>
> ? ? return var
>
> transformed = [usefully_named_func(v) for v in sequence]
>
> > 3.) true OOP
> > Now before you go and get all "huffy" over this statement, hear me
> > out. Python is the best language in the world. But it damn sure has
> > some warts! "len(this)" instead of "obj.length" max(that) instead of
> > [1,2,3,4,5].max().
>
> As the Zen says: '[P]racticality beats purity'. Personally, I'm not
> sure how a handful of convenient built-in functions make a language in
> which _everything is an object_ somehow "false" OO.
>
> If you're really that concerned with writing "true" OO (for some
> wildly variable value of "true"), there's nothing stopping you from
> doing so now:
>
> ? ? obj.__len__()
>
> With max(), this is a built-in that takes _any_ iterable and an
> optional key function, and returns the highest value as per the key.
> This means that _every_ iterable object - as _well_ as every object
> that supports enough of the iterator protocol - can be handed to max()
> and a result obtained. So at best, I just need to make sure my new
> sequence-type provides the iterator protocol and viola, it works with
> max() without me having to hand-code a .max() that's specialised for
> my new type, and without Python forcing me to have a complex
> inheritance chain just to make sure I include the right
> MaxableSequence ancestor to inherit the right .max().
>
> > PS stay tuned for more from this series....
>
> Is this going to be more of you telling us - without any apparent
> irony whatsoever - how Ruby has some valid points after all your
> vilification last year when we said the same to you? ?If so, where can
> I sign up?!
>
> (You should consider trading guest spot posts with Xah Lee on your
> respective blogs. You both have a very similar approach to programming
> & programming languages and I think the synergy would be amazing to
> see.)

Here is some wisdom from Guido van Rossum on the matter:

http://mail.python.org/pipermail/python-dev/2006-May/064841.html


Carl Banks


From pdlemper at earthlink.net  Thu Jul 30 01:25:11 2009
From: pdlemper at earthlink.net (pdlemper at earthlink.net)
Date: Thu, 30 Jul 2009 00:25:11 -0500
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
Message-ID: <72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>

On Wed, 29 Jul 2009 21:36:31 -0700 (PDT), Carl Banks
<pavlovevidence at gmail.com> wrote:

>On Jul 29, 9:24?pm, pdlem... at earthlink.net wrote:
>> What is cmath, where did it come from and how does it differ from
>> the standard math module ??
>
>What happened when you did a keyword search for "cmath" in the Python
>library documentation?
>
>What happened when you entered "python cmath" in Google?
>
>
>Carl Banks

Thanks Carl & Chris.  I've read the Python doc 10.3 and now understand
its for complex arithmetic. 
I've used python a few months and expected to find cmath seperately
sort of as a " header file".  A text search failed.  I now understand
its in the Python Standard Library, which I assume is that big file
Python30\LIBS\libpython30.a        And this is not readable as text.
Dave


From wuwei23 at gmail.com  Thu Jul 30 01:28:06 2009
From: wuwei23 at gmail.com (alex23)
Date: Wed, 29 Jul 2009 22:28:06 -0700 (PDT)
Subject: IDLE Config Problems
References: <mailman.3922.1248902818.8015.python-list@python.org>
Message-ID: <89553ecc-a30e-4280-8a42-17a18af50ba9@v37g2000prg.googlegroups.com>

On Jul 30, 6:55?am, "Russ Davis" <Russ.Da... at njpines.state.nj.us>
wrote:
> I am just getting started with Python and have installed v. 2.5.4 ?
> Idle version 1.2.4 ?I can't seem to get the idle to display text. ?It
> seems as if the install went fine. ?I start up the idle and the screen
> is blank. ?No text. ?It seems as if I can type on the screen but I just
> can't see the characters.

Is this the official python.org distribution you're trying? I can't
speak from experience, but I'm wondering if it doesn't include the
pyreadline module by default, which you'll require under Windows
(although I would've expected to hear more problems like your's if
this is the case). You can easily check this by going to C:
\Python25\Lib\site-packages and looking for a folder or a file called
pyreadline. If it's not, you'll have to install it separately.

If you're not already familiar with it, I do recommend checking out
the ActiveState ActivePython distribution instead, especially if
you're working under Windows. It includes a lot of Windows-specific
3rd party modules, such as the win32all modules, and it definitely
includes pyreadline.

Is there any particular reason why you're opting for Python 2.5.x? 2.6
should be pretty compatible with most things in the 2.x stream and
it's a handy stepping stone towards using 3.x (which, admittedly, is
probably the last of your concerns when you're first setting up...)


From tjreedy at udel.edu  Thu Jul 30 01:35:19 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 01:35:19 -0400
Subject: gamma approximation : what is module cmath and where is it located
	?
In-Reply-To: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <h4rben$qc1$1@ger.gmane.org>

pdlemper at earthlink.net wrote:
> The following numerical approximation for Euler's Gamma function
> is found in http://en.wikipedia.org/wiki/Lanczos_approximation
> 
> from cmath import *

> But I can't figure out where it gets "cmath".

The Python documentation set has a module index. Really handy. I use it 
all the time. cmath is under 'c'.

To answer some of your question:

 >>> math.sqrt(-1)
Traceback (most recent call last):
   File "<pyshell#3>", line 1, in <module>
     math.sqrt(-1)
ValueError: math domain error
 >>> cmath.sqrt(-1)
1j

Which to use depends on the behavior you want.

tjr



From Ron.Barak at lsi.com  Thu Jul 30 02:01:28 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 07:01:28 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <4A708F68.1010505@ieee.org>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>


> -----Original Message-----
> From: Dave Angel [mailto:davea at ieee.org] 
> Sent: Wednesday, July 29, 2009 21:05
> To: Barak, Ron
> Cc: 'python-list at python.org'
> Subject: Re: Run pyc file without specifying python path ?
> 
> Barak, Ron wrote:
> > Hi,
> >
> > I wanted to make a python byte-code file executable, 
> expecting to be able to run it without specifying "python" on 
> the (Linux bash) command line.
> >
> > So, I wrote the following:
> >
> > [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
> >
> > print "hello"
> > [root at VMLinux1 python]#
> >
> > and made its pyc file executable:
> >
> > [root at VMLinux1 python]# ls -ls test_pyc.pyc
> > 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> > [root at VMLinux1 python]#
> >
> > So, I see:
> >
> > [root at VMLinux1 python]# file test_pyc.py*
> > test_pyc.py:  a python script text executable
> > test_pyc.pyc: python 2.3 byte-compiled
> > [root at VMLinux1 python]#
> >
> > If I try to do the following, no problem:
> >
> > [root at VMLinux1 python]# python test_pyc.pyc hello
> > [root at VMLinux1 python]#
> >
> > However, the following fails:
> >
> > [root at VMLinux1 python]# ./test_pyc.pyc
> > -bash: ./test_pyc.pyc: cannot execute binary file
> > [root at VMLinux1 python]#
> >
> > Is there a way to run a pyc file without specifying the 
> python path ?
> >
> > Bye,
> > Ron.
> >
> >   
> I don't currently run Unix, but I think I know the problem.
> 
> In a text file, the shell examines the first line, and if it 
> begins #! 
> it's assumed to point to the executable of an interpreter for 
> that text file.  Presumably the same trick doesn't work for a 
> .pyc file.
> 
> Why not write a trivial wrapper.py file, don't compile it, 
> and let that invoke the main code in the .pyc file?
> 
> Then make wrapper.py executable, and you're ready to go.
> 
> DaveA
> 
> 

Hi Dave,
Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.
Bye,
Ron. 

From deets at nospam.web.de  Thu Jul 30 02:33:54 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 08:33:54 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <slrnh71g6g.djc.nick@irishsea.home.craig-wood.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>
	<7dbs8nF2br07nU1@mid.uni-berlin.de>
	<slrnh71g6g.djc.nick@irishsea.home.craig-wood.com>
Message-ID: <7dct6iF2bhhshU1@mid.uni-berlin.de>

Nick Craig-Wood schrieb:
> Diez B. Roggisch <deets at nospam.web.de> wrote:
>>  MalC0de schrieb:
>>> hello there, I've a question :
>>> I want to know does python have any capability for using Ring0 and
>>> kernel functions for driver and device development stuff .
>>> if there's such a feature it is very good, and if there something for
>>> this kind that you know please refer me to some reference and show me
>>> some snippet .
>>  No, it can't do such things. At least it isn't embedded in the kernel - 
>>  in theory that might be possible, but given the timing-constraints and 
>>  concurrency-requirements, it's not really feasible.
> 
> You can write FUSE (file systems in userspace) drivers in python I believe.
> Not the same as running in ring0 but in most senses a kernel driver...

No. That's why it is called "userspace". The kernel just hooks into a 
running program.

Diez



From __peter__ at web.de  Thu Jul 30 02:41:00 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 30 Jul 2009 08:41 +0200
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
	<72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>
Message-ID: <h4rf9f$jmq$01$1@news.t-online.com>

pdlemper at earthlink.net wrote:

> I've used python a few months and expected to find cmath seperately
> sort of as a " header file".  A text search failed.  I now understand
> its in the Python Standard Library, which I assume is that big file
> Python30\LIBS\libpython30.a        

Python 3.1 is no longer maintained. I recommend that you upgrade to Python 3.1.

> And this is not readable as text.

The module is written in C. The source code for the 3.1 version is here:

http://svn.python.org/view/python/branches/release31-maint/Modules/cmathmodule.c?view=markup

If you want the source for all parts of python written in C you can download the sourcecode at

http://www.python.org/download/releases/3.1/

Peter




From deets at nospam.web.de  Thu Jul 30 02:43:27 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 08:43:27 +0200
Subject: Connecting multiple test cases in a sort of pipe
In-Reply-To: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>
References: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>
Message-ID: <7dctogF29q4c6U1@mid.uni-berlin.de>

Raghuram Devarakonda schrieb:
> Hi,
> 
> I have three functions - create(), list(), and delete(). create()
> creates a new name in the file system hierarchy while list() displays
> all such created names and delete() removes them. I would like to
> write test cases for each of these functions, say, test_create() ,
> test_list(), and test_delete() using the unittest module. It easily
> follows that test_list() and test_delete() will need to know the exact
> name that was created in test_create() in order to properly validate
> list() and delete(). One option is for test_create() to always use a
> hard coded name but unfortunately this is not feasible.
> 
> Another way would be for test_create() to pass the new name down to
> the next test case test_list() which would do the same and pass the
> name down to test_delete(). In other words, the requirement is to
> connect all three test cases in a kind of pipe. This facility is
> obviously not currently present in the unittest module and nor does it
> seem to be available in other frameworks (such as py.test and nose, I
> only skimmed the feature list).
> 
> I am thinking of implementing this feature on top of unittest.TestCase
> and would like to know what others think of the idea. Is there a
> framework that has similar feature? Or perhaps, given my requirement
> as stated above, is there some alternate way of implementing it? I
> greatly appreciate any feed back.

Write a TestCase-subclass that simply works like this:


class FileTests(TestCase):


    def test_create(self):
        self.created_file = create()
        assert something


    def test_list(self):
        self.test_create()
        delete(self.created_file)


Passing state around is one of the reasons objects have been invented :) 
And nobody ever said that you can't invoke a test-method from somewhere 
else.

Diez


From clp2 at rebertia.com  Thu Jul 30 02:53:36 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Wed, 29 Jul 2009 23:53:36 -0700
Subject: gamma approximation : what is module cmath and where is it 
	located ?
In-Reply-To: <h4rf9f$jmq$01$1@news.t-online.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
	<72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>
	<h4rf9f$jmq$01$1@news.t-online.com>
Message-ID: <50697b2c0907292353i479f5d70ke59a91c330b6d8f7@mail.gmail.com>

On Wed, Jul 29, 2009 at 11:41 PM, Peter Otten<__peter__ at web.de> wrote:
> pdlemper at earthlink.net wrote:
>
>> I've used python a few months and expected to find cmath seperately
>> sort of as a " header file". ?A text search failed. ?I now understand
>> its in the Python Standard Library, which I assume is that big file
>> Python30\LIBS\libpython30.a
>
> Python 3.1 is no longer maintained. I recommend that you upgrade to Python 3.1.

(He meant to say 3.0.x is no longer maintained.)

- Chris
-- 
http://blog.rebertia.com


From __peter__ at web.de  Thu Jul 30 03:06:31 2009
From: __peter__ at web.de (Peter Otten)
Date: Thu, 30 Jul 2009 09:06:31 +0200
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<dc77266c-940f-4679-9900-cc46ea766f85@c14g2000yqm.googlegroups.com>
	<72b2751isp5ro2hmq5ordm2nhf3ohjrtjk@4ax.com>
	<h4rf9f$jmq$01$1@news.t-online.com>
	<mailman.3936.1248936819.8015.python-list@python.org>
Message-ID: <h4rgp9$6vv$00$1@news.t-online.com>

Chris Rebert wrote:

> On Wed, Jul 29, 2009 at 11:41 PM, Peter Otten<__peter__ at web.de> wrote:
>> pdlemper at earthlink.net wrote:
>>
>>> I've used python a few months and expected to find cmath seperately
>>> sort of as a " header file".  A text search failed.  I now understand
>>> its in the Python Standard Library, which I assume is that big file
>>> Python30\LIBS\libpython30.a
>>
>> Python 3.1 is no longer maintained. I recommend that you upgrade to
>> Python 3.1.
> 
> (He meant to say 3.0.x is no longer maintained.)

Ouch. Thanks for the correction.



From xubin.cz at gmail.com  Thu Jul 30 03:12:33 2009
From: xubin.cz at gmail.com (xubin.cz)
Date: Thu, 30 Jul 2009 00:12:33 -0700 (PDT)
Subject: beautiful soup
Message-ID: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>

hi, everyone

Is there any pakage or module handling html document like beautiful
soup?

thanks a lot


From deets at nospam.web.de  Thu Jul 30 03:30:48 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 09:30:48 +0200
Subject: beautiful soup
In-Reply-To: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
References: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
Message-ID: <7dd0h8F2a2he0U1@mid.uni-berlin.de>

xubin.cz schrieb:
> hi, everyone
> 
> Is there any pakage or module handling html document like beautiful
> soup?

why don't you *use* beautiful soup? It is a module...

Diez


From enleverLesX_XXmcX at XmclavXeauX.com  Thu Jul 30 03:54:21 2009
From: enleverLesX_XXmcX at XmclavXeauX.com (Michel Claveau - MVP)
Date: Thu, 30 Jul 2009 09:54:21 +0200
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
Message-ID: <4a7151b2$0$17782$ba4acef3@news.orange.fr>

Hi!

> Python is interpreted

No. Python is compiled (--> .pyc)
But the term "to compile" is not always unambiguous...
And the notion of "compiler" is not attached to Python (the language), but is attached to the implementation.

@+

MCI


From massi_srb at msn.com  Thu Jul 30 03:54:31 2009
From: massi_srb at msn.com (Massi)
Date: Thu, 30 Jul 2009 00:54:31 -0700 (PDT)
Subject: Bug in IEHtmlWindow?
Message-ID: <8a5ed753-d437-45a6-8fee-300eea1207ca@c2g2000yqi.googlegroups.com>

Hi everyone, I'm trying to use IEHtmlWindow in my application (python
2.5, wxpython 2.8 on win xp). Everything is ok, but I encountered a
problem which also affects the demo. If I make a research on google a
strange message appears, saying (I'll try to translate from italian):

Error during execution.
Do you want to run the debug?

line 29:
error: 'r' is NULL or it is not an object

Did anybody have the same problem? is it a bug?
Thanks in advance for your help.


From masklinn at masklinn.net  Thu Jul 30 03:55:24 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 09:55:24 +0200
Subject: beautiful soup
In-Reply-To: <7dd0h8F2a2he0U1@mid.uni-berlin.de>
References: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
	<7dd0h8F2a2he0U1@mid.uni-berlin.de>
Message-ID: <A62D275B-D411-4DDD-B315-03073102082D@masklinn.net>

On 30 Jul 2009, at 09:30 , Diez B. Roggisch wrote:
> xubin.cz schrieb:
>> hi, everyone
>> Is there any pakage or module handling html document like beautiful
>> soup?
>
> why don't you *use* beautiful soup? It is a module...
Or lxml, which works a bit better than BF 3.1 (post parser change)  
nowadays.


From martin.hellwig at dcuktec.org  Thu Jul 30 04:03:26 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 09:03:26 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <h4qp7u$15od$1@adenine.netfront.net>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<87skgf83ua.fsf@rsw.digi.com.br>
	<mailman.3929.1248911448.8015.python-list@python.org>
	<h4qp7u$15od$1@adenine.netfront.net>
Message-ID: <sOydnT-s_a9SzuzXnZ2dnUVZ8imdnZ2d@bt.com>

Marcus Wanner wrote:
<cut>
>> Look for example to libusb, which provides a userspace environment and 
>> pyusb which uses that and provides an interface to Python.
>>
> iicr pyusb uses a c interface to libusb, not python...
> 

According to them they use ctypes indeed. Sorry if I was misleading in 
my explanation.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From martin.hellwig at dcuktec.org  Thu Jul 30 04:05:48 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 09:05:48 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <4a7151b2$0$17782$ba4acef3@news.orange.fr>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
Message-ID: <sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>

Michel Claveau - MVP wrote:
> Hi!
> 
>> Python is interpreted
> 
> No. Python is compiled (--> .pyc)
> But the term "to compile" is not always unambiguous...
> And the notion of "compiler" is not attached to Python (the language), but is attached to the implementation.
> 
> @+
> 
> MCI

Well the pyc, which I thought was the Python bytecode, is then 
interpreted by the VM.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From javier.collado at gmail.com  Thu Jul 30 04:17:24 2009
From: javier.collado at gmail.com (Javier Collado)
Date: Thu, 30 Jul 2009 10:17:24 +0200
Subject: string.Template issue
Message-ID: <c83cde5a0907300117l7ca2f415jbd1c714918bf2d28@mail.gmail.com>

Hello,

In the string.Template documentation
(http://docs.python.org/library/string.html) it's explained that if a
custom regular expression for pattern substitution is needed, it's
possible to override idpattern class attribute (whose default value is
[_a-z][_a-z0-9]*).

However, if the custom pattern that is needed is just uppercase
letters something like [A-Z]+ won't work because of the following line
in the _TemplateMetaclass class __init__ method:
cls.pattern = _re.compile(pattern, _re.IGNORECASE | _re.VERBOSE)

I would say that this is an error (IGNORECASE just shouldn't be there)
and that the line above should be:
cls.pattern = _re.compile(pattern, _re.VERBOSE)
and the default value for idpattern:
[_a-zA-Z][_a-zA-Z0-9]*

Do you agree on this? Is there any reason for the IGNORECASE option to
be passed to re.compile?

Best regards,
    Javier


From kunguz at gmail.com  Thu Jul 30 05:02:04 2009
From: kunguz at gmail.com (=?ISO-8859-9?Q?Kaan_AK=DE=DDT?=)
Date: Thu, 30 Jul 2009 11:02:04 +0200
Subject: Pyplot
Message-ID: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>

I am a newbee in Python. I have some problem with usage of Pyplot. I have a
loop that creates plot in every end of it. Problem starts here: The first
plot is fine but the second one is plotted onto the first plot. I use:

plt.cla()
plt.draw()
plt.hold(False)
plt.close()
plt.clf()

but nothing works. Perhaps I am having a problem with basics, please help me
if you know something about it.

Kaan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/bfea180c/attachment-0001.html>

From lists at cheimes.de  Thu Jul 30 05:10:32 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 30 Jul 2009 11:10:32 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
Message-ID: <h4ro29$rgo$1@ger.gmane.org>

Martin P. Hellwig wrote:
> Well the pyc, which I thought was the Python bytecode, is then
> interpreted by the VM.

Python is often referred as byte-code interpreted language. Most modern
languages are interpreted languages. The list [1] is rather long.
Technically speaking even native code is interpreted by the micro code
of most CPUs.

[1] http://en.wikipedia.org/wiki/Interpreted_language
[2] http://en.wikipedia.org/wiki/Microcode



From ben+python at benfinney.id.au  Thu Jul 30 05:14:54 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Thu, 30 Jul 2009 19:14:54 +1000
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
Message-ID: <878wi6v8fl.fsf@benfinney.id.au>

"Michel Claveau - MVP"<enleverLesX_XXmcX at XmclavXeauX.com> writes:

> Hi!
> 
> > Python is interpreted
> 
> No.

Yes. The same Python code is both interpreted and compiled so as to run
it.

> Python is compiled (--> .pyc)

The Python bytecode (the contents of the compiled ?foo.pyc? file) is
then interpreted by the run-time Python interpreter, to actually run the
program.

-- 
 \           ?Value your freedom or you will lose it, teaches history. |
  `\     ?Don't bother us with politics,? respond those who don't want |
_o__)                               to learn.? ?Richard Stallman, 2002 |
Ben Finney



From python at rgbaz.eu  Thu Jul 30 05:17:51 2009
From: python at rgbaz.eu (PythonAB)
Date: Thu, 30 Jul 2009 11:17:51 +0200
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
Message-ID: <157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>

>>
> Hi Dave,
> Your solution sort of defeats my intended purpose (sorry for not  
> divulging my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python  
> script, and look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want  
> a cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?)  
> version of the application, because it'll grow the resulting file  
> significantly, and I don't have the experience to know how it will  
> run on different Linuxes.
> Bye,
> Ron.

Hey Ron,

What i usually do to accomplish this is compile the script to a .pyc  
just like you
did and then call that pyc from another script that's not compiled.
so in your case the not compiled script looks like:

#!/usr/bin/env python

import test_pyc.pyc



then run that script...

hope this helps...



alternatively you might have a look at:
http://www.pyinstaller.org/



gr
Arno
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/f303bad5/attachment-0001.html>

From lists at cheimes.de  Thu Jul 30 05:27:51 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 30 Jul 2009 11:27:51 +0200
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
Message-ID: <h4rp2n$u0o$1@ger.gmane.org>

Barak, Ron wrote:
> Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.

Ask Google for binfmt-support. Hint: Each Python version has its own
magic header.

Christian



From kunguz at gmail.com  Thu Jul 30 05:29:28 2009
From: kunguz at gmail.com (=?ISO-8859-9?Q?Kaan_AK=DE=DDT?=)
Date: Thu, 30 Jul 2009 11:29:28 +0200
Subject: Pyplot
In-Reply-To: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
References: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
Message-ID: <8fa7fe790907300229i496f7886w3c92676e51e0d9fa@mail.gmail.com>

Please help me I have been dealing with this little piece of code for 2
days. I am stuck and loosing time with it.

plt.figure(count)
            plt.xlabel("Time steps")
            plt.ylabel("Values")
            plt.title("Output of ADCs")
            plt.plot(timing,adc0)
            plt.plot(timing,adc1)
            plt.plot(timing,adc3)
            plt.show()
            plt.clf()
            plt.cla()
            plt.close()

30 Temmuz 2009 11:02 tarihinde Kaan AK??T <kunguz at gmail.com> yazd?:

> I am a newbee in Python. I have some problem with usage of Pyplot. I have a
> loop that creates plot in every end of it. Problem starts here: The first
> plot is fine but the second one is plotted onto the first plot. I use:
>
> plt.cla()
> plt.draw()
> plt.hold(False)
> plt.close()
> plt.clf()
>
> but nothing works. Perhaps I am having a problem with basics, please help
> me if you know something about it.
>
> Kaan
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/6a93fb69/attachment-0001.html>

From lists at cheimes.de  Thu Jul 30 05:53:03 2009
From: lists at cheimes.de (Christian Heimes)
Date: Thu, 30 Jul 2009 11:53:03 +0200
Subject: Can you easy_install from your localhost?
In-Reply-To: <9c8c445f0907290857x27930acbvc5067a242e18ed17@mail.gmail.com>
References: <9c8c445f0907290857x27930acbvc5067a242e18ed17@mail.gmail.com>
Message-ID: <h4rqi0$2ss$1@ger.gmane.org>

Ronn Ross schrieb:
> I have a package i would like to store locally. If it is stored locally can
> I do something like ' easy_install http://localhost/package ' ? Thanks

You can do:

  easy_install /path/to/package-0.1.tar.gz

or you can put your packages into
/some/directory/simple/packagename/package-0.1.tar.gz and do:

  easy_install -i file:///some/directory packagename

Christian



From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 30 06:10:36 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 30 Jul 2009 10:10:36 GMT
Subject: gamma approximation : what is module cmath and where is it 
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<mailman.3932.1248928456.8015.python-list@python.org>
Message-ID: <pan.2009.07.30.10.10.36@REMOVE.THIS.cybersource.com.au>

On Wed, 29 Jul 2009 21:34:07 -0700, Chris Rebert wrote:

> The difference is that it handles complex numbers, whereas the plain
> "math" module doesn't.
> I would guess the reason there are separate modules is for performance,
> so as to avoid having to dispatch on type at runtime. But this is only a
> guess.


My understanding is that it is to avoid people who don't care about 
complex numbers being confused when math.sqrt(-1) returns 1j instead of 
raising an error.



-- 
Steven


From egcalso at gmail.com  Thu Jul 30 06:13:52 2009
From: egcalso at gmail.com (eman)
Date: Thu, 30 Jul 2009 03:13:52 -0700 (PDT)
Subject: Help on Reading Attached Image on Excel
Message-ID: <7a651be8-e653-448e-91a2-84af71c5f64d@p36g2000prn.googlegroups.com>

Anyone know how to read included images in Excel using Python?

I've tried xlrd and pyexcelerator, but i couldn't figure out how to do
it.

If anyone has experience in this, please help.

Thanks.


From steven at REMOVE.THIS.cybersource.com.au  Thu Jul 30 06:20:24 2009
From: steven at REMOVE.THIS.cybersource.com.au (Steven D'Aprano)
Date: 30 Jul 2009 10:20:24 GMT
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<mailman.3935.1248933706.8015.python-list@python.org>
Message-ID: <pan.2009.07.30.10.20.25@REMOVE.THIS.cybersource.com.au>

On Thu, 30 Jul 2009 07:01:28 +0100, Barak, Ron wrote:

> I wanted my application to "hide" the fact that it's a python script,
> and look as much as possible like it's a compiled program.

What do you think the "c" in .pyc stands for?

What it's not is a compiled to machine-code stand alone executable.


> The reason I don't just give my user a py file, is that I don't want 
> a cleaver user to change the innards of the script.

It's not the clever users you need to worry about, because they'll fix 
your bugs. It's the not-as-clever-as-they-think-they-are users you have 
to worry about. But frankly, the best way to deal with them is to make it 
absolutely clear that you don't provide free support for modified 
versions of the script, and as soon as they report a problem, you diff 
their version with the official version. If they vary, then you start 
charging them.

Before you go spending vast amounts of time and energy creating a fragile 
solution, it's worth you working out what it actually is you're trying to 
prevent. If it's just "I don't want anybody touching my precious, 
precious code!" then I have no sympathy and have no interest in helping 
you. If it's "The damn users have mucked up the script AGAIN and now they 
expect me to fix it for free!!!", then that's a social problem, not a 
technical one, and a social solution might save you a lot of wasted 
effort.




-- 
Steven


From clp2 at rebertia.com  Thu Jul 30 06:20:41 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 30 Jul 2009 03:20:41 -0700
Subject: gamma approximation : what is module cmath and where is it 
	located ?
In-Reply-To: <pan.2009.07.30.10.10.36@REMOVE.THIS.cybersource.com.au>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
	<mailman.3932.1248928456.8015.python-list@python.org>
	<pan.2009.07.30.10.10.36@REMOVE.THIS.cybersource.com.au>
Message-ID: <50697b2c0907300320s35658775tfacc182f16ce9711@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:10 AM, Steven
D'Aprano<steven at remove.this.cybersource.com.au> wrote:
> On Wed, 29 Jul 2009 21:34:07 -0700, Chris Rebert wrote:
>
>> The difference is that it handles complex numbers, whereas the plain
>> "math" module doesn't.
>> I would guess the reason there are separate modules is for performance,
>> so as to avoid having to dispatch on type at runtime. But this is only a
>> guess.
>
> My understanding is that it is to avoid people who don't care about
> complex numbers being confused when math.sqrt(-1) returns 1j instead of
> raising an error.

That seems a better and more plausible rationale than my guess. Kudos.

- Chris
-- 
http://blog.rebertia.com


From bieffe62 at gmail.com  Thu Jul 30 06:29:24 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 03:29:24 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
Message-ID: <41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com>

On Jul 30, 5:52?am, NighterNet <darkne... at gmail.com> wrote:
> I am trying to figure out how to send text or byte in python 3.1. I am
> trying to send data to flash socket to get there. I am not sure how to
> work it.
>
> buff= 'id=' , self.id , ':balive=False\n'
> clientSock.send(buff);

Try putting a 'b' before the constant string that you want to send:

>>> type(b'123')
<class 'bytes'>

or use something like this to convert non constant strings (with only
ASCII characters) into bytes:

>>> s = "A non-constant string : %d " % n
>>> s
'A non-constant string : 12 '
>>> type(s)
<class 'str'>
>>> b = bytes ( ord(c) for c in s )
>>> b
b'A non-constant string : 12 '

You could also use struct.pack , that in python 3.x returns bytes and
not strings. In this case you need to specify the size of the string
(extra
bytes are zero-filled):

import struct

>>> struct.pack( "30s", "A non-constant string : %d " % n )
b'A non-constant string : 12 \x00\x00\x00'



Ciao
-----
FB


From marco at sferacarta.com  Thu Jul 30 06:29:50 2009
From: marco at sferacarta.com (Marco Mariani)
Date: Thu, 30 Jul 2009 12:29:50 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <yCecm.2708$I16.503@tornado.fastwebnet.it>

r wrote:

> My adventures in Ruby.

Oh, it's you.
Good boy.
Now, why don't you have a look at javascript and come back in six months?
Or better yet, haskell and twelve months.

thanks



From wolfgang at rohdewald.de  Thu Jul 30 06:35:22 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 12:35:22 +0200
Subject: New implementation of re module
In-Reply-To: <a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<mailman.3792.1248722883.8015.python-list@python.org>
	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
Message-ID: <200907301235.22563.wolfgang@rohdewald.de>

On Tuesday 28 July 2009, Christopher Arndt wrote:
> setup(name='regex',
>     version='1.0',
>     py_modules = ['regex'],
>     ext_modules=[Extension('_regex', ['_regex.c'])],
> )
>
> Also, you need to copy "unicodedata_db.h" from the "Modules"
> directory of the Python source tree to your working directory,
> since this file apparently is not installed into the include
> directory of a Python installation.

using issue2636-20090729.zip

I have Python 2.6.2 on ubuntu 9.04

with ggc-4.3:
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
build/temp.linux-i686-2.6/_regex.o
_regex.c: In Funktion ?bmatch_context?:
_regex.c:1462: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
_regex.c:1470: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
_regex.c:1478: Fehler: Als Verringerungsoperand wird L-Wert erfordert

with gcc-4.4:
gcc-4.4 -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-
prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
build/temp.linux-i686-2.6/_regex.o
_regex.c: In function ?bmatch_context?:
_regex.c:1462: error: lvalue required as increment operand
_regex.c:1470: error: lvalue required as increment operand
_regex.c:1478: error: lvalue required as decrement operand


-- 
Wolfgang


From Ron.Barak at lsi.com  Thu Jul 30 06:42:52 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 11:42:52 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>



________________________________
From: PythonAB [mailto:python at rgbaz.eu]
Sent: Thursday, July 30, 2009 12:18
To: Barak, Ron
Cc: 'Dave Angel'; 'python-list at python.org'
Subject: Re: Run pyc file without specifying python path ?


Hi Dave,
Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.
Bye,
Ron.

Hey Ron,

What i usually do to accomplish this is compile the script to a .pyc just like you
did and then call that pyc from another script that's not compiled.
so in your case the not compiled script looks like:

#!/usr/bin/env python

import test_pyc.pyc



then run that script...

hope this helps...



alternatively you might have a look at:
http://www.pyinstaller.org/



gr
Arno
[BR] Thanks for the answer Arno. But, I wonder -

How is your suggestion, which to the user would look like:
python wrapper.py

different (from the user's point-of-view) than the following:
python test_pyc.pyc ?

I'm trying to avoide having to write python on the command line.
Of course, I could write the wrapper is bourne shell, but that interoduces other problems (especially when considering that my real application needs to parse many command line options).
.
Bye,
Ron.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/24be79c0/attachment-0001.html>

From bieffe62 at gmail.com  Thu Jul 30 06:49:36 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 03:49:36 -0700 (PDT)
Subject: Python processors? : WAS Re: Does python have the capability for 
	driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr> 
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3939.1248945048.8015.python-list@python.org>
Message-ID: <2d8298b9-b857-4b3d-ae63-2056d80cdf7f@d4g2000yqa.googlegroups.com>

On Jul 30, 11:10?am, Christian Heimes <li... at cheimes.de> wrote:
> Martin P. Hellwig wrote:
> > Well the pyc, which I thought was the Python bytecode, is then
> > interpreted by the VM.
>
> Python is often referred as byte-code interpreted language. Most modern
> languages are interpreted languages. The list [1] is rather long.
> Technically speaking even native code is interpreted by the micro code
> of most CPUs.
>
> [1]http://en.wikipedia.org/wiki/Interpreted_language
> [2]http://en.wikipedia.org/wiki/Microcode

Once upon a time there where lisp machines, whith processors designed
to fastly execute lisp code  ... I worked with one of them for 2
years.
I wonder: has anybody thought of making a python-machine, or at least
a processor able to directly execute high-level bytecode (LLVM-like?).
I think the main feature of such a machine should be hyper-fast hash
lookup. Then dynamic memory management hardware ...

Ciao
-----
FB


From clp2 at rebertia.com  Thu Jul 30 06:57:40 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 30 Jul 2009 03:57:40 -0700
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
Message-ID: <50697b2c0907300357ld78846ch257547666a453829@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:42 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
>
>
> ________________________________
> From: PythonAB [mailto:python at rgbaz.eu]
> Sent: Thursday, July 30, 2009 12:18
> To: Barak, Ron
> Cc: 'Dave Angel'; 'python-list at python.org'
> Subject: Re: Run pyc file without specifying python path ?
>
>
> Hi Dave,
> Your solution sort of defeats my intended purpose (sorry for not divulging
> my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python script, and
> look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want a
> cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?) version of the
> application, because it'll grow the resulting file significantly, and I
> don't have the experience to know how it will run on different Linuxes.
> Bye,
> Ron.
>
> Hey Ron,
> What i usually do to accomplish this is compile the script to a .pyc just
> like you
> did and then call that pyc from another script that's not compiled.
> so in your case the not compiled script looks like:
> #!/usr/bin/env python
> import test_pyc.pyc
>
>
> then run that script...
> hope this helps...
>
>
> alternatively you might have a look at:
> http://www.pyinstaller.org/
>
>
> gr
> Arno
> [BR]?Thanks for the answer Arno. But, I wonder?-
>
> How is your suggestion, which to the user would look like:
> python wrapper.py

No, with the shebang line (and assuming execute permissions on the
file), it would look like:

./wrapper.py

(or just `wrapper.py` depending on whether the file is placed in the $PATH)

Cheers,
Chris
-- 
http://blog.rebertia.com


From python at mrabarnett.plus.com  Thu Jul 30 07:05:58 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 12:05:58 +0100
Subject: New implementation of re module
In-Reply-To: <200907301235.22563.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<mailman.3792.1248722883.8015.python-list@python.org>	<a70d808e-9b29-4091-90c2-da0f7c5fae7a@o6g2000yqj.googlegroups.com>
	<200907301235.22563.wolfgang@rohdewald.de>
Message-ID: <4A717E96.3020900@mrabarnett.plus.com>

Wolfgang Rohdewald wrote:
> On Tuesday 28 July 2009, Christopher Arndt wrote:
>> setup(name='regex',
>>     version='1.0',
>>     py_modules = ['regex'],
>>     ext_modules=[Extension('_regex', ['_regex.c'])],
>> )
>>
>> Also, you need to copy "unicodedata_db.h" from the "Modules"
>> directory of the Python source tree to your working directory,
>> since this file apparently is not installed into the include
>> directory of a Python installation.
> 
> using issue2636-20090729.zip
> 
> I have Python 2.6.2 on ubuntu 9.04
> 
> with ggc-4.3:
> gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
> Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
> build/temp.linux-i686-2.6/_regex.o
> _regex.c: In Funktion ?bmatch_context?:
> _regex.c:1462: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
> _regex.c:1470: Fehler: Als Erh?hungsoperand wird L-Wert erfordert
> _regex.c:1478: Fehler: Als Verringerungsoperand wird L-Wert erfordert
> 
> with gcc-4.4:
> gcc-4.4 -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-
> prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
> build/temp.linux-i686-2.6/_regex.o
> _regex.c: In function ?bmatch_context?:
> _regex.c:1462: error: lvalue required as increment operand
> _regex.c:1470: error: lvalue required as increment operand
> _regex.c:1478: error: lvalue required as decrement operand
> 
There are other lines which are similar, eg line 1487. Do they all give
the same/similar error with your compiler?


From masklinn at masklinn.net  Thu Jul 30 07:36:49 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 13:36:49 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>

On 30 Jul 2009, at 06:04 , alex23 wrote:
> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>> 1.) No need to use "()" to call a function with no arguments.
>> Python --> "obj.m2().m3()" --ugly
>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>> Man, i must admit i really like this, and your code will look so much
>> cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?
>
As chris pointed out, there's a method for that, to which a symbol is  
provided: `Object#method(methodname)`, which is basically equivalent  
to `getattr(object, methodname)` in Python.

>> 2.) the .each method
>> container.each{|localVar| block}
>> This method can really cleanup some ugly for loops, although i really
>> like the readability of for loops.
>
> map(lambda localVar: <block>, sequence)
>
> or:
>
> def usefully_named_func(var):
>    <block>
>    return var
>
> transformed = [usefully_named_func(v) for v in sequence]
>
The issue here is of course that `map` and comprehensions are  
transformations. `#each` exists for effectful iterations (Ruby has  
`#map` for the map operation). So the intent expressed by `#each` and  
`map` isn't the same. Furthermore and this is the most problematic  
limitation of Python here, `lambda` doesn't allow complex  
transformations due to its restrictions, so one has to switch to named  
functions which works but isn't sexy (and tends to lower readability  
imo).

>> 3.) true OOP
>> Now before you go and get all "huffy" over this statement, hear me
>> out. Python is the best language in the world. But it damn sure has
>> some warts! "len(this)" instead of "obj.length" max(that) instead of
>> [1,2,3,4,5].max().
>
> As the Zen says: '[P]racticality beats purity'. Personally, I'm not
> sure how a handful of convenient built-in functions make a language in
> which _everything is an object_ somehow "false" OO.
>
That's an interesting point, but not relevant at the end of the day:  
`foo.length` and `length(foo)` have the same "practicality". On the  
other hand Ruby can be praised for the coherence: everything's a  
method period end of the story; while Python does have a dichotomy  
between methods and functions/generic methods (whether or not that  
dichotomy bothers users is another issue).

> With max(), this is a built-in that takes _any_ iterable and an
> optional key function, and returns the highest value as per the key.
> This means that _every_ iterable object - as _well_ as every object
> that supports enough of the iterator protocol - can be handed to max()
> and a result obtained. So at best, I just need to make sure my new
> sequence-type provides the iterator protocol and viola, it works with
> max() without me having to hand-code a .max() that's specialised for
> my new type, and without Python forcing me to have a complex
> inheritance chain just to make sure I include the right
> MaxableSequence ancestor to inherit the right .max().
>
Well interestingly, Ruby works pretty much the same way. Where Python  
asks that you implement the iterator protocol to have `max` work, Ruby  
asks that you implement the `each` method (also called the Enumerable  
protocol) and mixin `Enumerable` (http://ruby-doc.org/core/classes/Enumerable.html 
). Then you get max (and min, map, etc?) "for free". Of course you're  
free to re-implement all of them manually if you wish to do so (or if  
you need those operations to return your custom collection rather than  
arrays). Enumerable is merely a convenience mixin. So there's no big  
difference here (and note that mixins aren't necessarily part of the  
inheritance chain, though they're implemented that way in Ruby).

Also, it's "voil?" not "viola" (a viola is a bowed string instrument,  
slightly bigger than a violin, whereas voil? is a french interjection  
used to call attention or suggest the appearance of something, as if  
by magic).

>> PS stay tuned for more from this series....
>
> Is this going to be more of you telling us - without any apparent
> irony whatsoever - how Ruby has some valid points after all your
> vilification last year when we said the same to you?  If so, where can
> I sign up?!
I fear I'll have to agree with that sentiment.

From bruno.42.desthuilliers at websiteburo.invalid  Thu Jul 30 07:40:05 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Thu, 30 Jul 2009 13:40:05 +0200
Subject: Does underscore has any special built-in meaningin Python ?
In-Reply-To: <87ljm72h04.fsf@benfinney.id.au>
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<87ljm72h04.fsf@benfinney.id.au>
Message-ID: <4a718695$0$2760$426a34cc@news.free.fr>

Ben Finney a ?crit :
> dandi kain <dandi.kain at gmail.com> writes:
> 
>> What is the functionality of __ or _ , leading or trailing an object ,
>> class ot function ?

<OP>
Please note that in Python, classes and functions are objects too. But 
anyway, these underscores are part of *identifiers*, not objects 
themselves !-)
</OP>

>     foo      Ordinary name, part of public interface
>     _foo     Ordinary name, part of internal-only interface
>     __foo    Ordinary name, but will be mangled (this style used rarely)
>     __foo__  Name which is used in a special way by Python

And FWIW:

      foo_     When you want to use a reserved name for identifier (ie: 
'class_' , 'or_', 'and_' etc)


From no.email at please.post  Thu Jul 30 08:02:06 2009
From: no.email at please.post (kj)
Date: Thu, 30 Jul 2009 12:02:06 +0000 (UTC)
Subject: How to "gunzip-iterate" over a file?
References: <h4qa2g$i5v$1@reader1.panix.com>
	<mailman.3916.1248898979.8015.python-list@python.org>
	<7x8wi7j80g.fsf@ruckus.brouhaha.com>
Message-ID: <h4s23u$h6g$1@reader1.panix.com>



Robert, Paul, thanks.  That was just what I was looking for.

kynn


From user at example.net  Thu Jul 30 08:03:38 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 14:03:38 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.3951.1248953823.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<mailman.3951.1248953823.8015.python-list@python.org>
Message-ID: <4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>

Masklinn wrote:
...
> That's an interesting point, but not relevant at the end of the day:  
> `foo.length` and `length(foo)` have the same "practicality". On the  
> other hand Ruby can be praised for the coherence: everything's a  method 
> period end of the story; while Python does have a dichotomy  between 
> methods and functions/generic methods (whether or not that  dichotomy 
> bothers users is another issue).
...
how would you correct a newbie (like me) who says:

"well, the main difference between a function and a method (from the 
caller's pow) is a syntactic one:

fun(obj, arguments)

as opposed to:

obj.met(arguments)

but the effect is just about the same."

?

bye


From Ray.Joseph at CDICorp.com  Thu Jul 30 08:17:05 2009
From: Ray.Joseph at CDICorp.com (ray)
Date: Thu, 30 Jul 2009 05:17:05 -0700 (PDT)
Subject: Looking for a dream language: sounds like Python to me.
References: <mailman.3743.1248636898.8015.python-list@python.org> 
	<m21vo2czeb.fsf@cs.uu.nl> <468250.83203.qm@web31106.mail.mud.yahoo.com>
	<4A6DC0FC.90704@stoneleaf.us>
	<880dece00907270812g1a4bcd25l63754cb7a26f7900@mail.gmail.com> 
	<5b8d13220907270822i7e641387ob4b0a7503d21284@mail.gmail.com> 
	<880dece00907270828y1ad33407re4c52e6b81f8abfc@mail.gmail.com> 
	<mailman.3784.1248709156.8015.python-list@python.org>
	<b9b5898f-c18e-4235-871a-7fcaef1b7c33@p15g2000vbl.googlegroups.com>
	<mailman.3840.1248791727.8015.python-list@python.org>
Message-ID: <976e1fea-4f40-49be-81e1-493456fcf52d@o36g2000vbl.googlegroups.com>

> Where can I find a Python functionality like simulink ??

Stef,

I saw this at:
http://showmedo.com/videotutorials/video?name=7430000&fromSeriesID=743

Ray


From jeanmichel at sequans.com  Thu Jul 30 08:24:39 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 30 Jul 2009 14:24:39 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<mailman.3951.1248953823.8015.python-list@python.org>
	<4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
Message-ID: <4A719107.9020500@sequans.com>

superpollo wrote:
> Masklinn wrote:
> ...
>> That's an interesting point, but not relevant at the end of the day:  
>> `foo.length` and `length(foo)` have the same "practicality". On the  
>> other hand Ruby can be praised for the coherence: everything's a  
>> method period end of the story; while Python does have a dichotomy  
>> between methods and functions/generic methods (whether or not that  
>> dichotomy bothers users is another issue).
> ...
> how would you correct a newbie (like me) who says:
>
> "well, the main difference between a function and a method (from the 
> caller's pow) is a syntactic one:
>
> fun(obj, arguments)
>
> as opposed to:
>
> obj.met(arguments)
>
> but the effect is just about the same."
>
> ?
>
> bye

My suggestion

- OO programming:
length(foo) calls the foo instance(or class for some language) length method
length(bar) calls the bar instance length method, it is **not** the same 
than the foo method

- non OO programming:
length(foo) calls the length function with foo as parameter
length(bar) calls the **same** length function with the bar parameter 
(so you better make sure length is handling both foo and bar)

So the difference is definitely **not** a syntactic one, but it is true 
that the syntax obj.method() better illustrates the bind mechanism of 
the OO programming.

JM



From clp2 at rebertia.com  Thu Jul 30 08:27:12 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Thu, 30 Jul 2009 05:27:12 -0700
Subject: Python processors? : WAS Re: Does python have the capability for 
	driver development ?
In-Reply-To: <2d8298b9-b857-4b3d-ae63-2056d80cdf7f@d4g2000yqa.googlegroups.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3939.1248945048.8015.python-list@python.org>
	<2d8298b9-b857-4b3d-ae63-2056d80cdf7f@d4g2000yqa.googlegroups.com>
Message-ID: <50697b2c0907300527o37e2353vb2fa7d62e2f9ebdd@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:49 AM, Francesco Bochicchio<bieffe62 at gmail.com> wrote:
> On Jul 30, 11:10?am, Christian Heimes <li... at cheimes.de> wrote:
>> Martin P. Hellwig wrote:
>> > Well the pyc, which I thought was the Python bytecode, is then
>> > interpreted by the VM.
>>
>> Python is often referred as byte-code interpreted language. Most modern
>> languages are interpreted languages. The list [1] is rather long.
>> Technically speaking even native code is interpreted by the micro code
>> of most CPUs.
>>
>> [1]http://en.wikipedia.org/wiki/Interpreted_language
>> [2]http://en.wikipedia.org/wiki/Microcode
>
> Once upon a time there where lisp machines, whith processors designed
> to fastly execute lisp code ?... I worked with one of them for 2
> years.
> I wonder: has anybody thought of making a python-machine, or at least
> a processor able to directly execute high-level bytecode (LLVM-like?).
> I think the main feature of such a machine should be hyper-fast hash
> lookup. Then dynamic memory management hardware ...

Yes, it was considered a decade ago:
http://mail.python.org/pipermail/python-list/1999-June/004451.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From wolfgang at rohdewald.de  Thu Jul 30 08:29:07 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 14:29:07 +0200
Subject: New implementation of re module
In-Reply-To: <4A717E96.3020900@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<200907301235.22563.wolfgang@rohdewald.de>
	<4A717E96.3020900@mrabarnett.plus.com>
Message-ID: <200907301429.07850.wolfgang@rohdewald.de>

On Thursday 30 July 2009, MRAB wrote:
> There are other lines which are similar, eg line 1487. Do they all
> give the same/similar error with your compiler?

yes. The full output with gcc-4.3:


notebook:~/kmj/src$ LANG=C python setup.py  build
running build
running build_py
running build_ext
building '_regex' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
build/temp.linux-i686-2.6/_regex.o
_regex.c: In function 'bmatch_context':
_regex.c:1462: error: lvalue required as increment operand
_regex.c:1470: error: lvalue required as increment operand
_regex.c:1478: error: lvalue required as decrement operand
_regex.c:1487: error: lvalue required as decrement operand
_regex.c:1593: error: lvalue required as increment operand
_regex.c:1606: error: lvalue required as decrement operand
_regex.c:1616: error: lvalue required as increment operand
_regex.c:1625: error: lvalue required as increment operand
_regex.c:1634: error: lvalue required as decrement operand
_regex.c:1643: error: lvalue required as decrement operand
_regex.c:2036: error: lvalue required as increment operand
_regex.c:2047: error: lvalue required as increment operand
_regex.c:2059: error: lvalue required as decrement operand
_regex.c:2070: error: lvalue required as decrement operand
_regex.c:2316: error: lvalue required as increment operand
In file included from _regex.c:2431:
_regex.c: In function 'umatch_context':
_regex.c:1462: error: lvalue required as increment operand
_regex.c:1470: error: lvalue required as increment operand
_regex.c:1478: error: lvalue required as decrement operand
_regex.c:1487: error: lvalue required as decrement operand
_regex.c:1593: error: lvalue required as increment operand
_regex.c:1606: error: lvalue required as decrement operand
_regex.c:1616: error: lvalue required as increment operand
_regex.c:1625: error: lvalue required as increment operand
_regex.c:1634: error: lvalue required as decrement operand
_regex.c:1643: error: lvalue required as decrement operand
_regex.c:2036: error: lvalue required as increment operand
_regex.c:2047: error: lvalue required as increment operand
_regex.c:2059: error: lvalue required as decrement operand
_regex.c:2070: error: lvalue required as decrement operand
_regex.c:2316: error: lvalue required as increment operand
error: command 'gcc' failed with exit status 1

-- 
Wolfgang


From masklinn at masklinn.net  Thu Jul 30 08:30:48 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 14:30:48 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<mailman.3951.1248953823.8015.python-list@python.org>
	<4a718c1a$0$6163$4fafbaef@reader5.news.tin.it>
Message-ID: <AAEFAD09-9104-4B1B-A111-367BCD255752@masklinn.net>

On 30 Jul 2009, at 14:03 , superpollo wrote:
> Masklinn wrote:
> ...
>> That's an interesting point, but not relevant at the end of the  
>> day:  `foo.length` and `length(foo)` have the same "practicality".  
>> On the other hand Ruby can be praised for the coherence:  
>> everything's a  method period end of the story; while Python does  
>> have a dichotomy  between methods and functions/generic methods  
>> (whether or not that  dichotomy bothers users is another issue).
> ...
> how would you correct a newbie (like me) who says:
>
> "well, the main difference between a function and a method (from the  
> caller's pow) is a syntactic one:
>
> fun(obj, arguments)
>
> as opposed to:
>
> obj.met(arguments)
>
> but the effect is just about the same."
>
> ?
Depending on the way things are implemented, it can be very similar  
(see CLOS' generic functions, which have the same look as functions  
but dispatch based on parameter types).

In Python, the difference would be that functions don't automatically  
dispatch (you have a function for everybody, and any dispatch you  
perform based on argument types or other qualifiers has to be done  
manually) whereas methods do dispatch on the first [implied] argument  
(you execute a precise method corresponding to the object it's being  
called on).

So fun(obj, *arguments) will call the same `fun` whether `obj` is an  
int, a string or an HTTPFactory whereas obj.met(*arguments) will call  
a different `met` each time (they all have the same "unqualified" name  
[and signature if it's part of a protocol], but might very well be  
implemented completely differently). Therefore -- in python -- the  
effect isn't anywhere "just about the same".



From beldar.cat at gmail.com  Thu Jul 30 08:40:41 2009
From: beldar.cat at gmail.com (Beldar)
Date: Thu, 30 Jul 2009 05:40:41 -0700 (PDT)
Subject: Regexp problem
Message-ID: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>

Hi there!

I have a problem and i'm not very good at regular expressions.
I have a text like "lalala lalala tiruri beldar-is-listening tiruri
lalala" I need a regexp to get the 'beldar' part, the format is
'something-is-listening', i need to get the something part, use it in
my code, and then replace the whole 'something-is-listening' for
another string.

Someone can help me please? Thank you!


From nobody at nowhere.com  Thu Jul 30 08:43:29 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 30 Jul 2009 13:43:29 +0100
Subject: gamma approximation : what is module cmath and where is it
	located ?
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <pan.2009.07.30.12.43.29.62000@nowhere.com>

On Wed, 29 Jul 2009 23:24:11 -0500, pdlemper wrote:

> The following numerical approximation for Euler's Gamma function
> is found in http://en.wikipedia.org/wiki/Lanczos_approximation
> 
> from cmath import *

> This works in Python 3.0    
>   
> But I can't figure out where it gets "cmath".    Searching the Python 
> directory reveals no more than a test_cmath.  The only cmath I can find
> is a header file in another directory  turboc++\Borland\include\
> 
> dir(cmath) reveals 23 functions overlapping the 37 functions of
> the math module.
> 
> What is cmath, where did it come from and how does it differ from
> the standard math module  ?

If you're looking for the file, it's written in C, so it's typically a
dynamic library, e.g.:

	/usr/lib/python2.5/lib-dynload/cmath.so

You won't find a cmath.py file.



From nytrokiss at gmail.com  Thu Jul 30 08:45:09 2009
From: nytrokiss at gmail.com (James Matthews)
Date: Thu, 30 Jul 2009 15:45:09 +0300
Subject: Image merging
Message-ID: <8a6b8e350907300545i48de1284h82e3c4d9d249ff8@mail.gmail.com>

Hi,

I need to create an app that takes to images and mergers them. After
googling around I have found 4 graphic library's that I can use. However
since I am new to "image programming" can you please tell me which one you
think would be the best.

The ones I found were

cairographics
PIL
Imagemagick
GraphicsMagick

Any tips?

Thanks
James

-- 
http://www.goldwatches.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/922dcff8/attachment-0001.html>

From python at rgbaz.eu  Thu Jul 30 08:54:21 2009
From: python at rgbaz.eu (PythonAB)
Date: Thu, 30 Jul 2009 14:54:21 +0200
Subject: Run pyc file without specifying python path ?
In-Reply-To: <50697b2c0907300357ld78846ch257547666a453829@mail.gmail.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
	<50697b2c0907300357ld78846ch257547666a453829@mail.gmail.com>
Message-ID: <736F147B-47A0-4559-8FC3-4134068B5F09@rgbaz.eu>


On 30 jul 2009, at 12:57, Chris Rebert wrote:

> On Thu, Jul 30, 2009 at 3:42 AM, Barak, Ron<Ron.Barak at lsi.com> wrote:
>>
>>
>> ________________________________
>> From: PythonAB [mailto:python at rgbaz.eu]
>> Sent: Thursday, July 30, 2009 12:18
>> To: Barak, Ron
>> Cc: 'Dave Angel'; 'python-list at python.org'
>> Subject: Re: Run pyc file without specifying python path ?
>>
>>
>> Hi Dave,
>> Your solution sort of defeats my intended purpose (sorry for not  
>> divulging
>> my 'hidden agenda').
>> I wanted my application to "hide" the fact that it's a python  
>> script, and
>> look as much as possible like it's a compiled program.
>> The reason I don't just give my user a py file, is that I don't  
>> want a
>> cleaver user to change the innards of the script.
>> On the other hand, I don't want to make a compiled (freezed?)  
>> version of the
>> application, because it'll grow the resulting file significantly,  
>> and I
>> don't have the experience to know how it will run on different  
>> Linuxes.
>> Bye,
>> Ron.
>>
>> Hey Ron,
>> What i usually do to accomplish this is compile the script to  
>> a .pyc just
>> like you
>> did and then call that pyc from another script that's not compiled.
>> so in your case the not compiled script looks like:
>> #!/usr/bin/env python
>> import test_pyc.pyc
>>
>>
>> then run that script...
>> hope this helps...
>>
>>
>> alternatively you might have a look at:
>> http://www.pyinstaller.org/
>>
>>
>> gr
>> Arno
>> [BR] Thanks for the answer Arno. But, I wonder -
>>
>> How is your suggestion, which to the user would look like:
>> python wrapper.py
>
> No, with the shebang line (and assuming execute permissions on the
> file), it would look like:
>
> ./wrapper.py
>
> (or just `wrapper.py` depending on whether the file is placed in the  
> $PATH)
>
> Cheers,
> Chris
>

yes exactly, chris

you can distribute a pyc containing your program, and have the  
wrapper.py execute it

gr
Arno 


From python at mrabarnett.plus.com  Thu Jul 30 08:56:32 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 13:56:32 +0100
Subject: New implementation of re module
In-Reply-To: <200907301429.07850.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<200907301235.22563.wolfgang@rohdewald.de>	<4A717E96.3020900@mrabarnett.plus.com>
	<200907301429.07850.wolfgang@rohdewald.de>
Message-ID: <4A719880.3070300@mrabarnett.plus.com>

Wolfgang Rohdewald wrote:
> On Thursday 30 July 2009, MRAB wrote:
>> There are other lines which are similar, eg line 1487. Do they all
>> give the same/similar error with your compiler?
> 
> yes. The full output with gcc-4.3:
> 
> 
> notebook:~/kmj/src$ LANG=C python setup.py  build
> running build
> running build_py
> running build_ext
> building '_regex' extension
> gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -
> Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c _regex.c -o 
> build/temp.linux-i686-2.6/_regex.o
> _regex.c: In function 'bmatch_context':
> _regex.c:1462: error: lvalue required as increment operand
[snip]
> error: command 'gcc' failed with exit status 1
> 
So it complains about:

     ++(RE_CHAR*)context->text_ptr

but not about:

     ++info->repeat.count

Does this mean that the gcc compiler thinks that the cast makes it an
rvalue? I'm using Visual C++ 2008 Express Edition, which doesn't
complain. What does the C standard say?


From davea at dejaviewphoto.com  Thu Jul 30 09:02:55 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Thu, 30 Jul 2009 09:02:55 -0400
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
Message-ID: <4A7199FF.8010202@dejaviewphoto.com>

Barak, Ron wrote:
>> -----Original Message-----
>> From: Dave Angel [mailto:davea at ieee.org] 
>> Sent: Wednesday, July 29, 2009 21:05
>> To: Barak, Ron
>> Cc: 'python-list at python.org'
>> Subject: Re: Run pyc file without specifying python path ?
>>
>> Barak, Ron wrote:
>>     
>>> Hi,
>>>
>>> I wanted to make a python byte-code file executable, 
>>>       
>> expecting to be able to run it without specifying "python" on 
>> the (Linux bash) command line.
>>     
>>> So, I wrote the following:
>>>
>>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
>>>
>>> print "hello"
>>> [root at VMLinux1 python]#
>>>
>>> and made its pyc file executable:
>>>
>>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
>>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
>>> [root at VMLinux1 python]#
>>>
>>> So, I see:
>>>
>>> [root at VMLinux1 python]# file test_pyc.py*
>>> test_pyc.py:  a python script text executable
>>> test_pyc.pyc: python 2.3 byte-compiled
>>> [root at VMLinux1 python]#
>>>
>>> If I try to do the following, no problem:
>>>
>>> [root at VMLinux1 python]# python test_pyc.pyc hello
>>> [root at VMLinux1 python]#
>>>
>>> However, the following fails:
>>>
>>> [root at VMLinux1 python]# ./test_pyc.pyc
>>> -bash: ./test_pyc.pyc: cannot execute binary file
>>> [root at VMLinux1 python]#
>>>
>>> Is there a way to run a pyc file without specifying the 
>>>       
>> python path ?
>>     
>>> Bye,
>>> Ron.
>>>
>>>   
>>>       
>> I don't currently run Unix, but I think I know the problem.
>>
>> In a text file, the shell examines the first line, and if it 
>> begins #! 
>> it's assumed to point to the executable of an interpreter for 
>> that text file.  Presumably the same trick doesn't work for a 
>> .pyc file.
>>
>> Why not write a trivial wrapper.py file, don't compile it, 
>> and let that invoke the main code in the .pyc file?
>>
>> Then make wrapper.py executable, and you're ready to go.
>>
>> DaveA
>>
>>
>>     
>
> Hi Dave,
> Your solution sort of defeats my intended purpose (sorry for not divulging my 'hidden agenda').
> I wanted my application to "hide" the fact that it's a python script, and look as much as possible like it's a compiled program.
> The reason I don't just give my user a py file, is that I don't want a cleaver user to change the innards of the script.
> On the other hand, I don't want to make a compiled (freezed?) version of the application, because it'll grow the resulting file significantly, and I don't have the experience to know how it will run on different Linuxes.
> Bye,
> Ron. 
>   
Most of the other answers basically paraphrased my suggestion of making 
a wrapper file, not compiling it, and making it executable.  With that 
approach, the user just types   "wrapper.py" on his command line.

And wrapper.py only needs two lines, a shebang, and an import, no big 
deal if the user modifies it.  The rest of your code can be .pyc files.

Steven makes some good points.  You have to define what level of clever 
you're protecting from.  A determined hacker will get in no matter what 
you do, unless you want to ship the program in a proprietary embedded 
system, encased in epoxy.  Further, if you have an extension of .py or 
.pyc, a knowledgeable hacker will know it's probably python.

You imply you want it to run unmodifed on multiple unknown Linux 
versions.  I think that lets out binfmt solutions.  That means you need 
to test and support not only multiple Linux implementations, but 
multiple Python versions, because who knows what the user may have 
installed.  I think you need to rethink your support strategy.  And 
maybe concentrate on being able to detect change, rather than prevent it.

DaveA




From python.list at tim.thechases.com  Thu Jul 30 09:04:24 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Thu, 30 Jul 2009 08:04:24 -0500
Subject: Regexp problem
In-Reply-To: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
Message-ID: <4A719A58.4020509@tim.thechases.com>

> I have a problem and i'm not very good at regular expressions.
> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
> lalala" I need a regexp to get the 'beldar' part, the format is
> 'something-is-listening', i need to get the something part, use it in
> my code, and then replace the whole 'something-is-listening' for
> another string.


Pretty easy:

   >>> import re
   >>> s = "lalala lalala tiruri beldar-is-listening tiruri lalala"
   >>> r = re.compile(r'(\w+)-is-listening')
   >>> r.search(s).group(1)
   'beldar'
   >>> r.sub('this is a replacement', s)
   'lalala lalala tiruri this is a replacement tiruri lalala'

-tkc




From python at mrabarnett.plus.com  Thu Jul 30 09:07:51 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 14:07:51 +0100
Subject: Regexp problem
In-Reply-To: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
Message-ID: <4A719B27.8000404@mrabarnett.plus.com>

Beldar wrote:
> Hi there!
> 
> I have a problem and i'm not very good at regular expressions.
> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
> lalala" I need a regexp to get the 'beldar' part, the format is
> 'something-is-listening', i need to get the something part, use it in
> my code, and then replace the whole 'something-is-listening' for
> another string.
> 
\w+ will match a word and enclosing it in (...) will capture what was
matched:

     m = re.search(r"(\w+)-is-listening", text)
     print "Captured '%s'" % m.group(1)
     print "Matched from %d to %d" % (m.start(), m.end())


From wolfgang at rohdewald.de  Thu Jul 30 09:18:27 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 15:18:27 +0200
Subject: New implementation of re module
In-Reply-To: <4A719880.3070300@mrabarnett.plus.com>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<200907301429.07850.wolfgang@rohdewald.de>
	<4A719880.3070300@mrabarnett.plus.com>
Message-ID: <200907301518.28122.wolfgang@rohdewald.de>

On Thursday 30 July 2009, MRAB wrote:
> So it complains about:
>
>      ++(RE_CHAR*)context->text_ptr
>
> but not about:
>
>      ++info->repeat.count
>
> Does this mean that the gcc compiler thinks that the cast makes it
> an rvalue? I'm using Visual C++ 2008 Express Edition, which doesn't
> complain. What does the C standard say?

I am not really a C expert but I found some links. Most helpful:
http://developer.apple.com/DOCUMENTATION/DeveloperTools/gcc-4.0.1/gcc/C-Dialect-Options.html

(search -fnon-lvalue-assign)

so I did the conversion mentioned there. This works: 

--- _regex.c    2009-07-29 11:34:00.000000000 +0200
+++ n   2009-07-30 15:15:22.000000000 +0200
@@ -1459,7 +1459,7 @@
             if (text_ptr < (RE_CHAR*)context->slice_end && text_ptr[0] != '\n')
               {
                 context->node = node->next_1;
-                ++(RE_CHAR*)context->text_ptr;
+                ++*(RE_CHAR**)&context->text_ptr;
             } else
                 context = reject_context(state, context);
             break;


-- 
Wolfgang


From wfluro at gmail.com  Thu Jul 30 09:19:29 2009
From: wfluro at gmail.com (ulf)
Date: Thu, 30 Jul 2009 06:19:29 -0700 (PDT)
Subject: Python ctypes on win64
References: <f415d834-b2ac-4036-afb1-a12c79480eb4@i6g2000yqj.googlegroups.com>
	<h4dlvk$2is$1@panix3.panix.com>
Message-ID: <433d4958-81e4-4d5f-be51-9d1b2170d1eb@c2g2000yqi.googlegroups.com>

On Jul 25, 3:09?am, a... at pythoncraft.com (Aahz) wrote:
> In article <f415d834-b2ac-4036-afb1-a12c79480... at i6g2000yqj.googlegroups.com>,
Thanks, I'll try there.

>
> ulf ?<wfl... at gmail.com> wrote:
>
> >Does anybody know if python includes a win64 version ofctypes?
>
> >According to the documentation it should be included - at least
> >there's no special remarks for win64, and I haven't found any recent
> >notes saying that it shouldn't work on win64. Yet it looks like both
> >the installer from Python.org and from ActiveState.com have disabled
> >it.
>
> Nobody seems to have followed up to this, you may have better luck on
> the capi-sig mailing list.
> --
> Aahz (a... at pythoncraft.com) ? ? ? ? ? <*> ? ? ? ?http://www.pythoncraft.com/
>
> "At Resolver we've found it useful to short-circuit any doubt and just ? ? ? ?
> refer to comments in code as 'lies'. :-)"
> --Michael Foord paraphrases Christian Muirhead on python-dev, 2009-03-22



From davea at ieee.org  Thu Jul 30 09:20:45 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 09:20:45 -0400
Subject: Does python have the capability for driver development ?
In-Reply-To: <sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
Message-ID: <4A719E2D.708@ieee.org>

Martin P. Hellwig wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Michel 
> Claveau - MVP wrote:
>> Hi!
>>
>>> Python is interpreted
>>
>> No. Python is compiled (--> .pyc)
>> But the term "to compile" is not always unambiguous...
>> And the notion of "compiler" is not attached to Python (the 
>> language), but is attached to the implementation.
>>
>> @+
>>
>> MCI
>
> Well the pyc, which I thought was the Python bytecode, is then 
> interpreted by the VM.
>
As Michel says, "to compile" is not always unambiguous.  My definition 
includes a one-way transformation from human-readable source text into 
something that can be more efficiently interpreted by other code, or by 
hardware.  The compiler really doesn't care whether the machine it's 
targeting is real or virtual.

The CPython implementation of Python compiles the source text into a 
bytecode file, with extension .pyc.    That certainly is a compilation 
step.  Followed (much) later by an interpreted one.

To pick a specific implementation of C++,  Microsoft C++ compiles C++ 
source text into an "executable file,"  with extension .exe  (I'm 
ignoring little details, like the linker).  That's a compilation step.  
Then the exe file is (later) interpreted by the microcode on the Pentium 
chip.

As far as I know, nobody has yet built a microcode implementation of a 
Python VM (Virtual Machine).  Nor have I seen one for the Java VM.  
However, in the early 80's there was a microcode implementation of the 
P-system VM.  It was never a commercial success, but it existed.  And 
there have been at least three Forth machines, where the hardware itself 
was designed to support the language's VM.  No microcode at all.

DaveA


From wolfgang at rohdewald.de  Thu Jul 30 09:24:28 2009
From: wolfgang at rohdewald.de (Wolfgang Rohdewald)
Date: Thu, 30 Jul 2009 15:24:28 +0200
Subject: New implementation of re module
In-Reply-To: <200907301518.28122.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<4A719880.3070300@mrabarnett.plus.com>
	<200907301518.28122.wolfgang@rohdewald.de>
Message-ID: <200907301524.28703.wolfgang@rohdewald.de>

On Thursday 30 July 2009, Wolfgang Rohdewald wrote:
> so I did the conversion mentioned there. This works:

I actually do not know if it works - but it compiles.

-- 
Wolfgang


From beldar.cat at gmail.com  Thu Jul 30 09:32:59 2009
From: beldar.cat at gmail.com (Beldar)
Date: Thu, 30 Jul 2009 06:32:59 -0700 (PDT)
Subject: Regexp problem
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
	<mailman.3961.1248959276.8015.python-list@python.org>
Message-ID: <30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>

On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Beldar wrote:
> > Hi there!
>
> > I have a problem and i'm not very good at regular expressions.
> > I have a text like "lalala lalala tiruri beldar-is-listening tiruri
> > lalala" I need a regexp to get the 'beldar' part, the format is
> > 'something-is-listening', i need to get the something part, use it in
> > my code, and then replace the whole 'something-is-listening' for
> > another string.
>
> \w+ will match a word and enclosing it in (...) will capture what was
> matched:
>
> ? ? ?m = re.search(r"(\w+)-is-listening", text)
> ? ? ?print "Captured '%s'" % m.group(1)
> ? ? ?print "Matched from %d to %d" % (m.start(), m.end())

Ok, thank you all, it was very helpful!


From ccurvey at gmail.com  Thu Jul 30 09:35:46 2009
From: ccurvey at gmail.com (Chris Curvey)
Date: Thu, 30 Jul 2009 06:35:46 -0700 (PDT)
Subject: PyPDF and print restrictions
References: <90034475-cf07-4a57-b8cf-ec2949e0e544@d23g2000vbm.googlegroups.com>
Message-ID: <13cc96b6-7c1b-4835-b711-eabedb4d6442@f10g2000vbf.googlegroups.com>

On Jul 27, 4:16?pm, Chris Curvey <ccur... at gmail.com> wrote:
> Has anyone out there been able to enforce print restrictions on a PDF
> document by usingPyPDF? The documentation for "encrypt" states:
>
> ?# @param user_pwd The "user password", which allows for opening and
> reading
> ?# the PDF file with the restrictions provided.
>
> But there is no parameter for providing a restriction, and I can't
> find a reference to any kind of restriction besides this comment in
> the docs.
>
> Thanks in advance!

I found some (I think old-ish) documentation on encryption and
permissions (of course, I've lost the link).  I think there are
additional permissions that have been implemented since the doc that I
found, but this patch works for me.

Index: C:/Documents and Settings/ccurvey/PyPDF/pyPdf/pdf.py
===================================================================
--- C:/Documents and Settings/ccurvey/PyPDF/pyPdf/pdf.py	(revision 1)
+++ C:/Documents and Settings/ccurvey/PyPDF/pyPdf/pdf.py	(revision 2)
@@ -118,7 +118,10 @@
     # @param use_128bit Boolean argument as to whether to use 128bit
     # encryption.  When false, 40bit encryption will be used.  By
default, this
     # flag is on.
-    def encrypt(self, user_pwd, owner_pwd = None, use_128bit = True):
+    # @param perm_mask bitmask of the permissions that should be
granted.
+    # Defaults to -1, which is "everything permitted"
+    def encrypt(self, user_pwd, owner_pwd = None, use_128bit = True,
+                perm_mask=-1):
         import md5, time, random
         if owner_pwd == None:
             owner_pwd = user_pwd
@@ -130,8 +133,8 @@
             V = 1
             rev = 2
             keylen = 40 / 8
-        # permit everything:
-        P = -1
+
+        P = perm_mask
         O = ByteStringObject(_alg33(owner_pwd, user_pwd, rev,
keylen))
         ID_1 = md5.new(repr(time.time())).digest()
         ID_2 = md5.new(repr(random.random())).digest()
Index: C:/Documents and Settings/ccurvey/PyPDF/pyPdf/__init__.py
===================================================================
--- C:/Documents and Settings/ccurvey/PyPDF/pyPdf/__init__.py
(revision 1)
+++ C:/Documents and Settings/ccurvey/PyPDF/pyPdf/__init__.py
(revision 2)
@@ -1,2 +1,11 @@
 from pdf import PdfFileReader, PdfFileWriter
+
+PERM_NONE = 0
+PERM_PRINT = 2
+PERM_MODIFY = 4
+PERM_COPY_TEXT = 8
+PERM_ANNOTATE = 16
+
+PERM_ALL = PERM_PRINT | PERM_MODIFY | PERM_COPY_TEXT | PERM_ANNOTATE
+
 __all__ = ["pdf"]


From marcusw at cox.net  Thu Jul 30 09:38:49 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Thu, 30 Jul 2009 09:38:49 -0400
Subject: Regexp problem
In-Reply-To: <30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
	<mailman.3961.1248959276.8015.python-list@python.org>
	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
Message-ID: <h4s7pm$rgr$1@adenine.netfront.net>

On 7/30/2009 9:32 AM, Beldar wrote:
> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> Beldar wrote:
>>> Hi there!
>>> I have a problem and i'm not very good at regular expressions.
>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>> 'something-is-listening', i need to get the something part, use it in
>>> my code, and then replace the whole 'something-is-listening' for
>>> another string.
>> \w+ will match a word and enclosing it in (...) will capture what was
>> matched:
>>
>>      m = re.search(r"(\w+)-is-listening", text)
>>      print "Captured '%s'" % m.group(1)
>>      print "Matched from %d to %d" % (m.start(), m.end())
> 
> Ok, thank you all, it was very helpful!
Wow, I really need to learn more about regexp...
Any tutorials you guys can recommend?

Marcus


From piet at cs.uu.nl  Thu Jul 30 09:39:35 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 30 Jul 2009 15:39:35 +0200
Subject: New implementation of re module
References: <mailman.3787.1248712420.8015.python-list@python.org>
Message-ID: <m21vnye1d4.fsf@cs.uu.nl>

>>>>> MRAB <python at mrabarnett.plus.com> (M) wrote:

>M> Hi all,
>M> I've been working on a new implementation of the re module. The details
>M> are at http://bugs.python.org/issue2636, specifically from
>M> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>M> Python 2.6 on Windows if you want to try it out.

>M> I'm interested in how fast it is generally, compared with the current re
>M> module, but especially when faced with those 'pathological' regular
>M> expressions which seem to take a long time to finish, for example:

>M>     re.search(r"^(.+|D)*A$", "x" * 25 + "B")

>M> which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs
>M> with this new implementation.

Is this version also going to use the Thompson approach?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From martin.hellwig at dcuktec.org  Thu Jul 30 09:43:26 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 14:43:26 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <mailman.3963.1248960056.8015.python-list@python.org>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
Message-ID: <uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>

Dave Angel wrote:
<cut definition/interpretation of compiling>
Ah yes, we thread on the territory of word definition and difference in 
interpretation. Any argument is doomed to fail if not agreed or at least 
taken in perspective of the terminology used by users.

I could be (well it is quite likely) wrong in my interpretation of the 
terminology, but here goes it anyway:

Machine Code:
Whatever the machine executes, it could be that the CPU uses an 
abstraction of microcode to do this but from the perspective of the 
user, this is all done in the same 'black box'

Compiling:
Translate words/symbols/mnemonics to machine code, which than can be 
either loaded, linked and executed by an OS or read and executed by the 
BIOS.

Interpreted:
Instructions which can be fed to a previous compiled program that is 
able to dynamically change its execution and flow without the need to 
recompile itself.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From piet at cs.uu.nl  Thu Jul 30 09:45:44 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Thu, 30 Jul 2009 15:45:44 +0200
Subject: Semaphore Techniques
References: <004e308e-2621-4411-bb1d-8c0f23259367@d4g2000yqa.googlegroups.com>
	<f695cf45-8932-4254-b2d8-fae32728083d@e27g2000yqm.googlegroups.com>
	<m2fxcfefu2.fsf@cs.uu.nl>
	<8cb1ba65-be71-49b7-8955-54c17f351a40@w6g2000yqw.googlegroups.com>
Message-ID: <m2ws5qcmif.fsf@cs.uu.nl>

>>>>> Carl Banks <pavlovevidence at gmail.com> (CB) wrote:

>CB> On Jul 29, 7:14?am, Piet van Oostrum <p... at cs.uu.nl> wrote:
>>> >>>>> Carl Banks <pavlovevide... at gmail.com> (CB) wrote:
>>> >CB> On Jul 28, 3:15?pm, John D Giotta <jdgio... at gmail.com> wrote:
>>> >>> I'm looking to run a process with a limit of 3 instances, but each
>>> >>> execution is over a crontab interval. I've been investigating the
>>> >>> threading module and using daemons to limit active thread objects, but
>>> >>> I'm not very successful at grasping the documentation.
>>> 
>>> >>> Is it possible to do what I'm trying to do and if so anyone know of a
>>> >>> useful example to get started?
>>> >CB> It seems like you want to limit the number of processes to three; the
>>> >CB> threading module won't help you there because it deals with threads
>>> >CB> within a single process.
>>> >CB> What I'd do is to simply run the system ps to see how many processes
>>> >CB> are running (ps is pretty versatile on most systems and can find
>>> >CB> specifically targeted processes like you program), and exit if there
>>> >CB> are already three.
>>> 
>>> That will surely run into some race conditions.

>CB> What, the OS might not have gotten around to update the process table
>CB> to include a process started minutes ago?  (He said he was starting
>CB> the processes over crontab intervals, not that he communicated what he
>CB> wanted well.)

No but between the time you get the ps output and decide not to start a
new process one of the processes might have exited. As I said it
probably is not a big deal, but you (he) should be aware of it I think.

The other possible race condition: two processes starting at
approximately the same time and both not detecting the other will
probably not occur because of the time distance between starting the
processes by cron. Unless the system is so busy that ps takes a loooong
time. 

The problem is similar to the sleeping barber problem (3 sleeping
barbers actually).
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From davea at ieee.org  Thu Jul 30 09:53:31 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 09:53:31 -0400
Subject: gamma approximation : what is module cmath and where is it located
	?
In-Reply-To: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
References: <ic6275dnpvqk3epditoomibfi4n5omnkui@4ax.com>
Message-ID: <4A71A5DB.60409@ieee.org>

pdlemper at earthlink.net wrote:
> from cmath import *
>  
> <snip>
> What is cmath, where did it come from and how does it differ from
> the standard math module  ?
>
> Dave WB3DWE
>                                    I saw the number 4 in silver,  Guido
>                                      (apologies to Wm Carlos Williams)
>
>   

I'm surprised that with all the responses, nobody has pointed out the 
dangers involved in using
     from cmath import *

In general, this form of import is discouraged.   I presume there's no 
problem if you're not also importing 'math' and all your calls are 
intending to be for the complex versions.  But if you're mixing things 
up, consider using the more conventional
     import  cmath

and using cmath.   as a prefix before the function calls.

DaveA



From metolone+gmane at gmail.com  Thu Jul 30 09:56:07 2009
From: metolone+gmane at gmail.com (Mark Tolonen)
Date: Thu, 30 Jul 2009 06:56:07 -0700
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
Message-ID: <h4s8pm$g3g$1@ger.gmane.org>


"NighterNet" <darkneter at gmail.com> wrote in message 
news:55aba832-df6d-455f-bf34-04d37eb061cd at i4g2000prm.googlegroups.com...
>I am trying to figure out how to send text or byte in python 3.1. I am
> trying to send data to flash socket to get there. I am not sure how to
> work it.
>
> buff= 'id=' , self.id , ':balive=False\n'
> clientSock.send(buff);
> -- 
> http://mail.python.org/mailman/listinfo/python-list
>

Python 3.1 strings are Unicode (think characters not bytes).  When writing 
to files, sockets, etc. bytes must be used.  Unicode strings have an 
encode() method, where you can specify an appropriate encoding (ascii, 
latin-1, windows-1252, utf-8, etc.):

    clientSock.send(buff.encode('ascii'))

When reading from the socket, you can decode() the byte strings back into 
Unicode strings.

    data = clientSock.recv(1024).decode('ascii')

-Mark




From bieffe62 at gmail.com  Thu Jul 30 10:11:24 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 07:11:24 -0700 (PDT)
Subject: No PyPI search for 3.x compatible packages
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
Message-ID: <d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>

On 30 Lug, 01:55, Neil Hodgson <nyamatongwe+thun... at gmail.com> wrote:
> ? ?There appears to be no way to search PyPI for packages that are
> compatible with Python 3.x. There are classifiers for 'Programming
> Language' including 'Programming Language :: Python :: 3' but that seems
> to be for implementation language since there are so many packages that
> specify C. There are a total of 109 packages classified with Python ::
> [3, 3.0, 3.1] out of a total of 4829 packages.http://pypi.python.org/pypi?:action=browse&show=all&c=214&c=533
>
> ? ?The search box appears to search for any word entered so a search
> like "xml 3.0" or "xml AND 3.0" does not help.
>
> ? ?Some packages include version information in the Py Version column of
> their download lists or embedded in the download file names. Projects
> are often constrained to a particular set of Python versions so need to
> choose packages that will work with those versions. It would be helpful
> if PyPI made this information more visible and searchable.
>
> ? ?Neil

Are you sure? I note that for example pygtk has as language tags both
C and python. So maybe a C extension
for python3 would have both C and python 3 as language tags.

I suspect that the 109 packages you found are the only ones obf the
4829 which works with python3 (but I hope
to be wrong ).

Ciao
-----
FB



From peter at peter-b.co.uk  Thu Jul 30 10:17:52 2009
From: peter at peter-b.co.uk (Peter Brett)
Date: Thu, 30 Jul 2009 15:17:52 +0100
Subject: Regexp problem
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>
	<mailman.3961.1248959276.8015.python-list@python.org>
	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
	<h4s7pm$rgr$1@adenine.netfront.net>
Message-ID: <we1mprbidzlb.fsf@ssclt003.ee.surrey.ac.uk>

Marcus Wanner <marcusw at cox.net> writes:

> On 7/30/2009 9:32 AM, Beldar wrote:
>> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>>> Beldar wrote:
>>>> Hi there!
>>>> I have a problem and i'm not very good at regular expressions.
>>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>>> 'something-is-listening', i need to get the something part, use it in
>>>> my code, and then replace the whole 'something-is-listening' for
>>>> another string.
>>> \w+ will match a word and enclosing it in (...) will capture what was
>>> matched:
>>>
>>>      m = re.search(r"(\w+)-is-listening", text)
>>>      print "Captured '%s'" % m.group(1)
>>>      print "Matched from %d to %d" % (m.start(), m.end())
>>
>> Ok, thank you all, it was very helpful!
> Wow, I really need to learn more about regexp...
> Any tutorials you guys can recommend?

I have to confess that after fiddling with regexps for quite a while
with no great success, I learnt the hard (and best) way, i.e. using
them to write something vile and horrible. [*] I commend this path to
you also. ;-)

Cheers,

                              Peter

[*] http://git.gpleda.org/?p=gaf.git;a=blob;f=libgeda/desktop-i18n;h=6fab9b85b

-- 
Peter Brett <peter at peter-b.co.uk>
Remote Sensing Research Group
Surrey Space Centre


From p.f.moore at gmail.com  Thu Jul 30 10:20:10 2009
From: p.f.moore at gmail.com (Paul Moore)
Date: Thu, 30 Jul 2009 15:20:10 +0100
Subject: No PyPI search for 3.x compatible packages
In-Reply-To: <d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
	<d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
Message-ID: <79990c6b0907300720s3a2ad4a8lf49bc265b653f55f@mail.gmail.com>

2009/7/30 Francesco Bochicchio <bieffe62 at gmail.com>:
> On 30 Lug, 01:55, Neil Hodgson <nyamatongwe+thun... at gmail.com> wrote:
>> ? ?There appears to be no way to search PyPI for packages that are
>> compatible with Python 3.x. There are classifiers for 'Programming
>> Language' including 'Programming Language :: Python :: 3' but that seems
>> to be for implementation language since there are so many packages that
>> specify C. There are a total of 109 packages classified with Python ::
>> [3, 3.0, 3.1] out of a total of 4829 packages.http://pypi.python.org/pypi?:action=browse&show=all&c=214&c=533
>>
>> ? ?The search box appears to search for any word entered so a search
>> like "xml 3.0" or "xml AND 3.0" does not help.
>>
>> ? ?Some packages include version information in the Py Version column of
>> their download lists or embedded in the download file names. Projects
>> are often constrained to a particular set of Python versions so need to
>> choose packages that will work with those versions. It would be helpful
>> if PyPI made this information more visible and searchable.
>>
>> ? ?Neil
>
> Are you sure? I note that for example pygtk has as language tags both
> C and python. So maybe a C extension
> for python3 would have both C and python 3 as language tags.
>
> I suspect that the 109 packages you found are the only ones obf the
> 4829 which works with python3 (but I hope
> to be wrong ).

Also, of course, they may not be the only ones that work, but merely
the only ones where the author has checked they work and tagged the
entry. It's quite possible that some packages will work unmodified...

Paul.


From kwatch at gmail.com  Thu Jul 30 10:30:25 2009
From: kwatch at gmail.com (kwatch)
Date: Thu, 30 Jul 2009 07:30:25 -0700 (PDT)
Subject: [ANN] pyKook 0.0.2 - a simple build tool similar to Make or Ant
Message-ID: <c0c0453c-c4ca-47a3-bf76-d2b7e2fad7ff@b25g2000prb.googlegroups.com>


Hi,

I have released pyKook 0.0.2.
http://pypi.python.org/pypi/Kook/0.0.2
http://www.kuwata-lab.com/kook/
http://www.kuwata-lab.com/kook/pykook-users-guide.html


Overview
--------

pyKook is a simple build tool similar to Make, Ant, Rake, or SCons.
pyKook regards software project as cooking.
Terms used in pyKook are cooking terms.
For example:

    cookbook    -  Makefile
    product     -  target file
    ingredient  -  source file
    recipe      -  how to create target from source
    spices      -  command-line options for recipe


Cookbook (= Makefile) is written in pure Python.
You can write any statements or expressions in cookbook.

NOTICE: pyKook is under alpha release. Spec and features may be
changed
in the future without previous announcement.


Example
-------

Example of cookbook (Kookbook.py):

    --------------------------------------------------
    ##
    ## properties
    ##
    cc     = prop('cc',     'gcc')
    cflags = prop('cflags', '-g -Wall')


    ##
    ## recipes
    ##
    @ingreds("hello")
    def task_all(c):
        pass

    @product("hello")
    @ingreds("hello.o")
    def file_command(c):
        """generates hello command"""
        system(c%"$(cc) $(cflags) -o $(product) $(ingred)")

    @product("*.o")
    @ingreds("$(1).c", if_exists("$(1).h"))
    def file_ext_o(c):
        """compile '*.c' and '*.h'"""
        system(c%"$(cc) $(cflags) -c $(1).c")

    def task_clean(c):
        rm_f("*.o")
    --------------------------------------------------


Exampe of result:

    ==================================================
    bash> ls
    Kookbook.py   hello.c    hello.h

    bash> pykook -l
    Properties:
      cc                  : 'gcc'
      cflags              : '-g -Wall'

    Task recipes:
      all                 : cook all products
      clean               : remove by-products

    File recipes:
      hello               : generates hello command
      *.o                 : compile '*.c' and '*.h'

    (Tips: you can set 'kook_default_product' variable in your
kookbook.)

    bash> pykook all           # or, pykook --cc=gcc4 all
    ### *** hello.o (func=file_ext_o)
    $ gcc -g -Wall -c hello.c
    ### ** hello (func=file_command)
    $ gcc -g -Wall -o hello hello.o
    ### * all (func=task_all)
    ==================================================


See users-guide for more details.
http://www.kuwata-lab.com/kook/pykook-users-guide.html


Enhancements, Changes, Bug fixes sice 0.0.1
-------------------------------------------


Enhancements:

- Python 3 support.

- Add 'kk' script which is shortcat for kk command.


Changes:

- Decorator '@cmdopts()' is renamed to '@spices()', and
  there is no need to call parse_cmdopts().

      ### prev version
      @cmdopts('-v: verbose', '-f file: filename')
      def task_example(c, *args):
          opts, rests = c.parse_cmdopts(args)
          verbose = opts.get('v', False):
          fileame = opts.get('f', None)

      ### since this release (0.0.2)
      @spices('-v: verbose', '-f file: filename')
      def task_example(c, *args, *kwargs):
          opts, rests = kwarts, args
          verbose = opts.get('v', False):
          fileame = opts.get('f', None)

- Remove 'pyk' script

- Testing library is changed from Python's unittest library
  into 'test/oktest.py'.


Bugfixes:

- glob2() now recognizes files on current directory.



Have fun!

--
regards,
makoto kuwata


From davea at ieee.org  Thu Jul 30 10:30:55 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 10:30:55 -0400
Subject: Does python have the capability for driver development ?
In-Reply-To: <uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>	<mailman.3963.1248960056.8015.python-list@python.org>
	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
Message-ID: <4A71AE9F.2000900@ieee.org>

Martin P. Hellwig wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Dave 
> Angel wrote:
> <cut definition/interpretation of compiling>
> Ah yes, we thread on the territory of word definition and difference 
> in interpretation. Any argument is doomed to fail if not agreed or at 
> least taken in perspective of the terminology used by users.
>
> I could be (well it is quite likely) wrong in my interpretation of the 
> terminology, but here goes it anyway:
>
> Machine Code:
> Whatever the machine executes, it could be that the CPU uses an 
> abstraction of microcode to do this but from the perspective of the 
> user, this is all done in the same 'black box'
>
> Compiling:
> Translate words/symbols/mnemonics to machine code, which than can be 
> either loaded, linked and executed by an OS or read and executed by 
> the BIOS.
>
> Interpreted:
> Instructions which can be fed to a previous compiled program that is 
> able to dynamically change its execution and flow without the need to 
> recompile itself.
>
Depending on the level of understanding of the user, plus his history 
and his biases, he will include more or less in his "black box."  In the 
old days, microcode was not "on-chip" but stored separately in control 
memory.  And on many machines, it was changeable at will.

To many users these days, the entire system including software is a 
black box, which gradually breaks down (gets slow, runs out of space, 
crashes a lot) and must be replaced.  They don't distinguish operating 
system from application, real memory from virtual, or viruses from 
bugs.  But of course those users wouldn't be participating in this 
discussion.

My background includes specifying hardware instruction sets and 
architecture.  And writing microcode for multiple machines.  And writing 
parts of compilers, interpreters, assemblers, and so on.  And 
microcoding interpreters.  And hooking into compilers to modify how they 
would generate code.   And hooking into runtimes to test running code in 
realtime.

So I tend to have very flexible definition of compiler and interpreter.  
Probably the only reason I jumped in here was the unmentioned bias that 
somehow a compiler is superior to an interpreter.

I think I'd better extend my definition of compilation.  It's a step 
that's statically taken over a series of instructions (not necessarily 
text source), that transforms it into a form closer to the targeted 
enviromment, real or virtual. Most C++ compilers have two compilers 
operating serially, the first to turn the source code into an 
intermediate form (like byte code), and the second to generate what is 
commonly called "machine code."  The second part of course is duplicated 
for each different target processor.

So Java is compiled into byte code, and the typical java VM then 
compiles that piecewise into machine code (so called JIT compiling, for 
just in time).

BTW, interpreters don't have to be written in a compiled language.


Anyway, I don't object to your definitions.  We all have different 
perspectives.

DaveA



From Ron.Barak at lsi.com  Thu Jul 30 10:47:37 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 15:47:37 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <4A7199FF.8010202@dejaviewphoto.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26D1@enbmail01.lsi.com>

 

> -----Original Message-----
> From: Dave Angel [mailto:davea at dejaviewphoto.com] 
> Sent: Thursday, July 30, 2009 16:03
> To: Barak, Ron
> Cc: 'Dave Angel'; 'python-list at python.org'
> Subject: RE: Run pyc file without specifying python path ?
> 
> Barak, Ron wrote:
> >> -----Original Message-----
> >> From: Dave Angel [mailto:davea at ieee.org]
> >> Sent: Wednesday, July 29, 2009 21:05
> >> To: Barak, Ron
> >> Cc: 'python-list at python.org'
> >> Subject: Re: Run pyc file without specifying python path ?
> >>
> >> Barak, Ron wrote:
> >>     
> >>> Hi,
> >>>
> >>> I wanted to make a python byte-code file executable,
> >>>       
> >> expecting to be able to run it without specifying "python" on the 
> >> (Linux bash) command line.
> >>     
> >>> So, I wrote the following:
> >>>
> >>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
> >>>
> >>> print "hello"
> >>> [root at VMLinux1 python]#
> >>>
> >>> and made its pyc file executable:
> >>>
> >>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> >>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> >>> [root at VMLinux1 python]#
> >>>
> >>> So, I see:
> >>>
> >>> [root at VMLinux1 python]# file test_pyc.py*
> >>> test_pyc.py:  a python script text executable
> >>> test_pyc.pyc: python 2.3 byte-compiled
> >>> [root at VMLinux1 python]#
> >>>
> >>> If I try to do the following, no problem:
> >>>
> >>> [root at VMLinux1 python]# python test_pyc.pyc hello
> >>> [root at VMLinux1 python]#
> >>>
> >>> However, the following fails:
> >>>
> >>> [root at VMLinux1 python]# ./test_pyc.pyc
> >>> -bash: ./test_pyc.pyc: cannot execute binary file
> >>> [root at VMLinux1 python]#
> >>>
> >>> Is there a way to run a pyc file without specifying the
> >>>       
> >> python path ?
> >>     
> >>> Bye,
> >>> Ron.
> >>>
> >>>   
> >>>       
> >> I don't currently run Unix, but I think I know the problem.
> >>
> >> In a text file, the shell examines the first line, and if 
> it begins 
> >> #!
> >> it's assumed to point to the executable of an interpreter for that 
> >> text file.  Presumably the same trick doesn't work for a .pyc file.
> >>
> >> Why not write a trivial wrapper.py file, don't compile it, and let 
> >> that invoke the main code in the .pyc file?
> >>
> >> Then make wrapper.py executable, and you're ready to go.
> >>
> >> DaveA
> >>
> >>
> >>     
> >
> > Hi Dave,
> > Your solution sort of defeats my intended purpose (sorry 
> for not divulging my 'hidden agenda').
> > I wanted my application to "hide" the fact that it's a 
> python script, and look as much as possible like it's a 
> compiled program.
> > The reason I don't just give my user a py file, is that I 
> don't want a cleaver user to change the innards of the script.
> > On the other hand, I don't want to make a compiled 
> (freezed?) version of the application, because it'll grow the 
> resulting file significantly, and I don't have the experience 
> to know how it will run on different Linuxes.
> > Bye,
> > Ron. 
> >   

Hi Dave,

> Most of the other answers basically paraphrased my suggestion 
> of making a wrapper file, not compiling it, and making it 
> executable.  With that 
> approach, the user just types   "wrapper.py" on his command line.
> 
> And wrapper.py only needs two lines, a shebang, and an 
> import, no big deal if the user modifies it.  The rest of 
> your code can be .pyc files.
> 
> Steven makes some good points.  You have to define what level 
> of clever you're protecting from.  A determined hacker will 

The clever I try to guard against is not at hacker level, just the curios worker.

> get in no matter what you do, unless you want to ship the 
> program in a proprietary embedded system, encased in epoxy.  
> Further, if you have an extension of .py or .pyc, a 
> knowledgeable hacker will know it's probably python.

Granted, but the user will know that from the user manual anyway :-)

> 
> You imply you want it to run unmodifed on multiple unknown 
> Linux versions.  I think that lets out binfmt solutions.  

Actually, no: I know the set of Linuxes my users are likely to have.

> That means you need to test and support not only multiple 
> Linux implementations, but multiple Python versions, because 
> who knows what the user may have installed.  I think you need 
> to rethink your support strategy.  And maybe concentrate on 
> being able to detect change, rather than prevent it.
> 
> DaveA
> 
> 

Thanks for the helpful suggestions.
Ron.
 

From invalid at invalid  Thu Jul 30 10:50:47 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 09:50:47 -0500
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<mailman.3959.1248959035.8015.python-list@python.org>
Message-ID: <tJWdnXjaWJnaLuzXnZ2dnUVZ_jdi4p2d@posted.visi>

On 2009-07-30, Dave Angel <davea at dejaviewphoto.com> wrote:

> Steven makes some good points.  You have to define what level
> of clever you're protecting from.  A determined hacker will
> get in no matter what you do, unless you want to ship the
> program in a proprietary embedded system, encased in epoxy.

That won't stop a dedicated reverse-engineering effort.  It
might take an X-ray machine, machine tools, various nasty
chemicals, and quite a bit of skill and patience -- but it can
be done.

> Further, if you have an extension of .py or .pyc, a
> knowledgeable hacker will know it's probably python.
>
> You imply you want it to run unmodifed on multiple unknown
> Linux versions.  I think that lets out binfmt solutions.  That
> means you need to test and support not only multiple Linux
> implementations, but multiple Python versions, because who
> knows what the user may have installed.  I think you need to
> rethink your support strategy.  And maybe concentrate on being
> able to detect change, rather than prevent it.

Or even being able to benefit from change. :)

-- 
Grant Edwards                   grante             Yow! FROZEN ENTREES may
                                  at               be flung by members of
                               visi.com            opposing SWANSON SECTS ...


From sajmikins at gmail.com  Thu Jul 30 10:52:46 2009
From: sajmikins at gmail.com (Simon Forman)
Date: Thu, 30 Jul 2009 10:52:46 -0400
Subject: Very Strange Problem
In-Reply-To: <77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
References: <77e5896b0907290826m2366e205ia933a9339dc70231@mail.gmail.com>
	<4A709B77.9080209@ieee.org>
	<77e5896b0907291210m26ecf5adlb292b895f649d7f3@mail.gmail.com>
Message-ID: <50f98a4c0907300752mbabd920ma208ca6a0b8f69f2@mail.gmail.com>

On Wed, Jul 29, 2009 at 3:10 PM, Omer Khalid<Omer.Khalid at cern.ch> wrote:
> Hi Dave,
>
> Thanks for your reply. I actually didn't cut and paste my code as it was
> dispersed in different places, i typed the logic behind my code in the email
> (and obiviously made some typos, indentations is some thing else) but my

Please, do not do  that.  It's very difficult to debug code that
hasn't been seen.  The code you posted has numerous problems (that
likely have nothing to do with your actual problem.)

If you're going to post code, try to recreate the issue with a small
runnable script.  If you can't do that, as it sounds like it would be
difficult in this case as your code is dispersed in different places,
at least post the relevant portions of the actual code.  Don't
re-type.

> real code does not have these problems as my application runs fine with out
> errors...
>
> Except that the line where i want to update the value doesn't get updated
> and no exception is thrown. What's surprising for me is that i am doing the
> same thing in hundreds of places in my 3k+ line code but by some reason this
> part doesn't work...
>
> As far as the global variables are concerned, i am using them in other
> places too and didn't see any problems.
>
> I think some thing else is going on here as the statement above and below my
> modified lines get executed.

If the statements above and below that line(s) are executed, then that
line is certainly being executed as well.

Try introducing some additional print statements to verify your mental
model of what's happening:

    # set it to 1
    print jobs
    print jobs[index]
    print jobs[index]['v']
    jobs[index]['v'] = 1
    print jobs
    print jobs[index]
    print jobs[index]['v']
    print "Set to 1"

> Is there a way in Python to debug memory address or to see where in memory
> this object is stored, and is there a lock on it or else?

You are barking up the wrong tree.  Somewhere in your code you're
doing something silly that's causing your issue.


From ben+python at benfinney.id.au  Thu Jul 30 10:53:35 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Fri, 31 Jul 2009 00:53:35 +1000
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
Message-ID: <87vdlate6o.fsf@benfinney.id.au>

"Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:

> Machine Code:
> Whatever the machine executes, it could be that the CPU uses an
> abstraction of microcode to do this but from the perspective of the
> user, this is all done in the same 'black box'

This requires, of course, defining what is the machine. Python bytecode
targets a virtual machine that is implemented differently for each
hardware platform.

> Compiling:
> Translate words/symbols/mnemonics to machine code, which than can be
> either loaded, linked and executed by an OS or read and executed by
> the BIOS.

Related to the above point, the ?machine code? can just as easily be
codes for a virtual machine specification. This is the case for the
bytecode instructions Python gets compiled to.

> Interpreted:
> Instructions which can be fed to a previous compiled program that is
> able to dynamically change its execution and flow without the need to
> recompile itself.

This doesn't make much sense to me, I must say.

I'd say, instead, that a program is interpreted if its instruction are
dynamically translated to underlying platform instructions at execution
time. This is the case for the bytecode instructions interpreted by the
Python virtual machine.

-- 
 \      ?Often, the surest way to convey misinformation is to tell the |
  `\               strict truth.? ?Mark Twain, _Following the Equator_ |
_o__)                                                                  |
Ben Finney


From invalid at invalid  Thu Jul 30 10:55:26 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 09:55:26 -0500
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
Message-ID: <tJWdnXvaWJnDKezXnZ2dnUVZ_jdi4p2d@posted.visi>

On 2009-07-30, Martin P. Hellwig <martin.hellwig at dcuktec.org> wrote:
> Michel Claveau - MVP wrote:
>
>>> Python is interpreted
>> 
>> No. Python is compiled (--> .pyc)
>> But the term "to compile" is not always unambiguous...
>> And the notion of "compiler" is not attached to Python (the
>> language), but is attached to the implementation.
>
> Well the pyc, which I thought was the Python bytecode,

It is, but that's just one particular implementation you're
talking about (though by far the most widely used one).

> is then interpreted by the VM.

Yup.  Just like .exe files are interpreted by the microcode in
the processor that implements the IA32 VM.  It would be quite
possible to put a Python VM into hardware.  Alternatevly, you
can compiler Python into Java bytecode and run that "directly"
on hardware.

-- 
Grant Edwards                   grante             Yow! It don't mean a
                                  at               THING if you ain't got
                               visi.com            that SWING!!


From draghuram at gmail.com  Thu Jul 30 10:59:40 2009
From: draghuram at gmail.com (Raghuram Devarakonda)
Date: Thu, 30 Jul 2009 07:59:40 -0700 (PDT)
Subject: Connecting multiple test cases in a sort of pipe
References: <f3bbd733-18c9-4756-be43-bd53ad0051ef@q35g2000vbi.googlegroups.com>
	<7dctogF29q4c6U1@mid.uni-berlin.de>
Message-ID: <63715814-ff14-4b95-9160-d98325640a8b@v20g2000yqm.googlegroups.com>

On Jul 30, 2:43 am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Write a TestCase-subclass that simply works like this:
>
> class FileTests(TestCase):
>
>     def test_create(self):
>         self.created_file = create()
>         assert something
>
>     def test_list(self):
>         self.test_create()
>         delete(self.created_file)
>
> Passing state around is one of the reasons objects have been invented :)
> And nobody ever said that you can't invoke a test-method from somewhere
> else.

Just to be clear, are you suggesting that these tests be run by a
custom runnner rather than by the default runner from unittest?

Thanks,
Raghu


From invalid at invalid  Thu Jul 30 11:03:56 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 10:03:56 -0500
Subject: Does python have the capability for driver development ?
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
Message-ID: <arCdnYGeC-LBK-zXnZ2dnUVZ_qidnZ2d@posted.visi>

On 2009-07-30, Dave Angel <davea at ieee.org> wrote:

> As far as I know, nobody has yet built a microcode implementation of a 
> Python VM (Virtual Machine).  Nor have I seen one for the Java VM.  

Didn't Sun or somebody do one 10-12 years ago?  Or did I
misinterpret some press release or something?  Off to google...

> However, in the early 80's there was a microcode implementation of the
> P-system VM.

Ah yes.  I remember sitting at an Intel MDS-80 "blue box" CP/M
system entering assembly language by hand for a simple Pascal
-> P-code compiler.  IIRC, I typed it from a listing in the
"Byte Big Book of Pascal".  That machine was pretty high-tech,
since I could save my work on an 8" floppy rather than a spool
of paper tape.  The floppy disks didn't leave big oil stains in
your backpack!

I got the compiler working, but I don't remember ever having a
VM and run-time system.

> It was never a commercial success, but it existed.  And there
> have been at least three Forth machines, where the hardware
> itself was designed to support the language's VM.  No
> microcode at all.

-- 
Grant Edwards                   grante             Yow! When you get your
                                  at               PH.D. will you get able to
                               visi.com            work at BURGER KING?


From keith at nekotaku.com  Thu Jul 30 11:09:20 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 08:09:20 -0700 (PDT)
Subject: Use existing IE cookie
Message-ID: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>

Hi there,

Relevant versions: Python 2.5, Vista Home, IE7

I am trying to scrape a website I have browsed manually in the past,
and also manually selected my options, and now want python to use my
existing cookie from the manual browse when downloading data.

Using: http://code.activestate.com/recipes/80443/ I have found the
"name" of the relevant cookie, just after reading urllib2 docs, I
can't see how to "send" or have my python instance use "MY" existing
cookie.

Using the following:

***
import re
import urllib2, cookielib

# set things up for cookies

opener = urllib2.build_opener(urllib2.HTTPCookieProcessor())
urllib2.install_opener(opener)

reply = urllib2.urlopen('foo.html').read()

print reply

***

This does return data, just default data, not the data from the
options I set up when manually browsing.

My sense is that I need "something" in the () part of
HTTPCookieProcessor() but I have no idea as to what... the docs say
"cookiejar" but the only code examples I have found are to create a
cookiejar for the existing Python session, not to use the cookies from
my prior manual meanderings.

Any help greatly appreciated.


From Ron.Barak at lsi.com  Thu Jul 30 11:10:17 2009
From: Ron.Barak at lsi.com (Barak, Ron)
Date: Thu, 30 Jul 2009 16:10:17 +0100
Subject: Run pyc file without specifying python path ?
In-Reply-To: <4A7199FF.8010202@dejaviewphoto.com>
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
Message-ID: <7F0503CD69378F49BE0DC30661C6CCF6701A26D2@enbmail01.lsi.com>

Hi Dave,

On second thoughts, I may have a problem implementing the wrapper solution, because my actual test_pyc.pyc, needs to parse its command line.
Namely, the actual call to test_pyc.pyc looks something like this:

$ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t tvn -p pool1 -l -c

And I don't know of a way to add these parameters to the "import  test_pyc" in wrapper

Is there a way to pass information to an imported module ? (Sorry if there's an obvious answer, I just cannot figure it out).

Bye,
Ron.

> -----Original Message-----
> From: Dave Angel [mailto:davea at dejaviewphoto.com] 
> Sent: Thursday, July 30, 2009 16:03
> To: Barak, Ron
> Cc: 'Dave Angel'; 'python-list at python.org'
> Subject: RE: Run pyc file without specifying python path ?
> 
> Barak, Ron wrote:
> >> -----Original Message-----
> >> From: Dave Angel [mailto:davea at ieee.org]
> >> Sent: Wednesday, July 29, 2009 21:05
> >> To: Barak, Ron
> >> Cc: 'python-list at python.org'
> >> Subject: Re: Run pyc file without specifying python path ?
> >>
> >> Barak, Ron wrote:
> >>     
> >>> Hi,
> >>>
> >>> I wanted to make a python byte-code file executable,
> >>>       
> >> expecting to be able to run it without specifying "python" on the 
> >> (Linux bash) command line.
> >>     
> >>> So, I wrote the following:
> >>>
> >>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
> >>>
> >>> print "hello"
> >>> [root at VMLinux1 python]#
> >>>
> >>> and made its pyc file executable:
> >>>
> >>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> >>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
> >>> [root at VMLinux1 python]#
> >>>
> >>> So, I see:
> >>>
> >>> [root at VMLinux1 python]# file test_pyc.py*
> >>> test_pyc.py:  a python script text executable
> >>> test_pyc.pyc: python 2.3 byte-compiled
> >>> [root at VMLinux1 python]#
> >>>
> >>> If I try to do the following, no problem:
> >>>
> >>> [root at VMLinux1 python]# python test_pyc.pyc hello
> >>> [root at VMLinux1 python]#
> >>>
> >>> However, the following fails:
> >>>
> >>> [root at VMLinux1 python]# ./test_pyc.pyc
> >>> -bash: ./test_pyc.pyc: cannot execute binary file
> >>> [root at VMLinux1 python]#
> >>>
> >>> Is there a way to run a pyc file without specifying the
> >>>       
> >> python path ?
> >>     
> >>> Bye,
> >>> Ron.
> >>>
> >>>   
> >>>       
> >> I don't currently run Unix, but I think I know the problem.
> >>
> >> In a text file, the shell examines the first line, and if 
> it begins 
> >> #!
> >> it's assumed to point to the executable of an interpreter for that 
> >> text file.  Presumably the same trick doesn't work for a .pyc file.
> >>
> >> Why not write a trivial wrapper.py file, don't compile it, and let 
> >> that invoke the main code in the .pyc file?
> >>
> >> Then make wrapper.py executable, and you're ready to go.
> >>
> >> DaveA
> >>
> >>
> >>     
> >
> > Hi Dave,
> > Your solution sort of defeats my intended purpose (sorry 
> for not divulging my 'hidden agenda').
> > I wanted my application to "hide" the fact that it's a 
> python script, and look as much as possible like it's a 
> compiled program.
> > The reason I don't just give my user a py file, is that I 
> don't want a cleaver user to change the innards of the script.
> > On the other hand, I don't want to make a compiled 
> (freezed?) version of the application, because it'll grow the 
> resulting file significantly, and I don't have the experience 
> to know how it will run on different Linuxes.
> > Bye,
> > Ron. 
> >   
> Most of the other answers basically paraphrased my suggestion 
> of making a wrapper file, not compiling it, and making it 
> executable.  With that 
> approach, the user just types   "wrapper.py" on his command line.
> 
> And wrapper.py only needs two lines, a shebang, and an 
> import, no big deal if the user modifies it.  The rest of 
> your code can be .pyc files.
> 
> Steven makes some good points.  You have to define what level 
> of clever you're protecting from.  A determined hacker will 
> get in no matter what you do, unless you want to ship the 
> program in a proprietary embedded system, encased in epoxy.  
> Further, if you have an extension of .py or .pyc, a 
> knowledgeable hacker will know it's probably python.
> 
> You imply you want it to run unmodifed on multiple unknown 
> Linux versions.  I think that lets out binfmt solutions.  
> That means you need to test and support not only multiple 
> Linux implementations, but multiple Python versions, because 
> who knows what the user may have installed.  I think you need 
> to rethink your support strategy.  And maybe concentrate on 
> being able to detect change, rather than prevent it.
> 
> DaveA
> 
> 
> 

From deets at nospam.web.de  Thu Jul 30 11:16:44 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 17:16:44 +0200
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
Message-ID: <7ddrqsF2b5mblU1@mid.uni-berlin.de>

KB wrote:

> Hi there,
> 
> Relevant versions: Python 2.5, Vista Home, IE7
> 
> I am trying to scrape a website I have browsed manually in the past,
> and also manually selected my options, and now want python to use my
> existing cookie from the manual browse when downloading data.
> 
> Using: http://code.activestate.com/recipes/80443/ I have found the
> "name" of the relevant cookie, just after reading urllib2 docs, I
> can't see how to "send" or have my python instance use "MY" existing
> cookie.
> 
> Using the following:
> 
> ***
> import re
> import urllib2, cookielib
> 
> # set things up for cookies
> 
> opener = urllib2.build_opener(urllib2.HTTPCookieProcessor())
> urllib2.install_opener(opener)
> 
> reply = urllib2.urlopen('foo.html').read()
> 
> print reply
> 
> ***
> 
> This does return data, just default data, not the data from the
> options I set up when manually browsing.
> 
> My sense is that I need "something" in the () part of
> HTTPCookieProcessor() but I have no idea as to what... the docs say
> "cookiejar" but the only code examples I have found are to create a
> cookiejar for the existing Python session, not to use the cookies from
> my prior manual meanderings.

Because this is a completely different beast. You need to find out if and
how to access IE-cookies from python - I guess some win32-road is to be
walked down for that.

Once you get a hold on them, you can build up whatever cookiejar urllib2
needs.

Diez


From invalid at invalid  Thu Jul 30 11:16:46 2009
From: invalid at invalid (Grant Edwards)
Date: Thu, 30 Jul 2009 10:16:46 -0500
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
	<mailman.3970.1248966648.8015.python-list@python.org>
Message-ID: <27mdnb-NxM3DJOzXnZ2dnUVZ_hxi4p2d@posted.visi>

On 2009-07-30, Barak, Ron <Ron.Barak at lsi.com> wrote:
> Hi Dave,
>
> On second thoughts, I may have a problem implementing the
> wrapper solution, because my actual test_pyc.pyc, needs to
> parse its command line. Namely, the actual call to
> test_pyc.pyc looks something like this:
>
> $ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t tvn -p pool1 -l -c
>
> And I don't know of a way to add these parameters to the
> "import test_pyc" in wrapper
>
> Is there a way to pass information to an imported module ?
> (Sorry if there's an obvious answer, I just cannot figure it
> out).

I don't understand your problem.  The module would parse
sys.argv just like always.

If you don't like that for some reason, you could define an
entry point in the module and call it:

#!/usr/bin/python
import sys,test_pyc
test_pyc.main(*sys.argv)

-- 
Grant Edwards                   grante             Yow! We just joined the
                                  at               civil hair patrol!
                               visi.com            


From keith at nekotaku.com  Thu Jul 30 11:19:08 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 08:19:08 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
Message-ID: <3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>


> > Using:http://code.activestate.com/recipes/80443/
>

Thanks for the prompt reply, Diez! Using the above I have found the
name of the cookie (I did google how to use IE cookies in python and
that was the best match) but it only tells me the name of the cookie,
not how to use it.

Any clues?

TIA!


From dkatkowski at gmail.com  Thu Jul 30 11:25:58 2009
From: dkatkowski at gmail.com (Feyo)
Date: Thu, 30 Jul 2009 08:25:58 -0700 (PDT)
Subject: Help with Regex for domain names
Message-ID: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>

I'm trying to figure out how to write efficiently write a regex for
domain names with a particular top level domain. Let's say, I want to
grab all domain names with country codes .us, .au, and .de.

I could create three different regexs that would work:
regex = re.compile(r'[\w\-\.]+\.us)
regex = re.compile(r'[\w\-\.]+\.au)
regex = re.compile(r'[\w\-\.]+\.de)

How would I write one to accommodate all three, or, better yet, to
accommodate a list of them that I can pass into a method call? Thanks!


From martin.hellwig at dcuktec.org  Thu Jul 30 11:41:56 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Thu, 30 Jul 2009 16:41:56 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <87vdlate6o.fsf@benfinney.id.au>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<4a7151b2$0$17782$ba4acef3@news.orange.fr>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<mailman.3963.1248960056.8015.python-list@python.org>
	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
	<87vdlate6o.fsf@benfinney.id.au>
Message-ID: <M-udnUIs853YIuzXnZ2dnUVZ8radnZ2d@bt.com>

Ben Finney wrote:
> "Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:
> 
>> Machine Code:
>> Whatever the machine executes, it could be that the CPU uses an
>> abstraction of microcode to do this but from the perspective of the
>> user, this is all done in the same 'black box'
> 
> This requires, of course, defining what is the machine. Python bytecode
> targets a virtual machine that is implemented differently for each
> hardware platform.
> 

I would further define 'black box' as the hardware a kernel programmer 
writes to.

<cut>

>> Interpreted:
>> Instructions which can be fed to a previous compiled program that is
>> able to dynamically change its execution and flow without the need to
>> recompile itself.
> 
> This doesn't make much sense to me, I must say.
> 
> I'd say, instead, that a program is interpreted if its instruction are
> dynamically translated to underlying platform instructions at execution
> time. This is the case for the bytecode instructions interpreted by the
> Python virtual machine.
> 

Yes that is indeed a much better description, I'll steal that from you :-)

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From deets at nospam.web.de  Thu Jul 30 11:43:31 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 17:43:31 +0200
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
Message-ID: <7ddtd3F297bafU1@mid.uni-berlin.de>

KB wrote:

> 
>> > Using:http://code.activestate.com/recipes/80443/
>>
> 
> Thanks for the prompt reply, Diez! Using the above I have found the
> name of the cookie (I did google how to use IE cookies in python and
> that was the best match) but it only tells me the name of the cookie,
> not how to use it.

Ah, sorry, should have read the recipe also. 

For me it looks as if findIECookie from that recipe is to be called with the
name. Then it should return the value, or None

What does you full example look like, including the
cookie-acquisition-stuff?

Diez


From tundra at tundraware.com  Thu Jul 30 11:47:06 2009
From: tundra at tundraware.com (Tim Daneliuk)
Date: Thu, 30 Jul 2009 10:47:06 -0500
Subject: Help with Regex for domain names
In-Reply-To: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
Message-ID: <msr8k6-dai1.ln1@ozzie.tundraware.com>

Feyo wrote:
> I'm trying to figure out how to write efficiently write a regex for
> domain names with a particular top level domain. Let's say, I want to
> grab all domain names with country codes .us, .au, and .de.
> 
> I could create three different regexs that would work:
> regex = re.compile(r'[\w\-\.]+\.us)
> regex = re.compile(r'[\w\-\.]+\.au)
> regex = re.compile(r'[\w\-\.]+\.de)
> 
> How would I write one to accommodate all three, or, better yet, to
> accommodate a list of them that I can pass into a method call? Thanks!

Just a point of interest:  A correctly formed domain name may have a
trailing period at the end of the TLD [1].  Example:

       foo.bar.com.

Though you do not often see this, it's worth accommodating "just in
case"...


[1] http://homepages.tesco.net/J.deBoynePollard/FGA/web-fully-qualified-domain-name.html



-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra at tundraware.com
PGP Key:         http://www.tundraware.com/PGP/


From python at mrabarnett.plus.com  Thu Jul 30 11:50:37 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 16:50:37 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <4A719E2D.708@ieee.org>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>
	<4A719E2D.708@ieee.org>
Message-ID: <4A71C14D.7030805@mrabarnett.plus.com>

Dave Angel wrote:
[snip]
> As far as I know, nobody has yet built a microcode implementation of a 
> Python VM (Virtual Machine).  Nor have I seen one for the Java VM.  
> However, in the early 80's there was a microcode implementation of the 
> P-system VM.  It was never a commercial success, but it existed.  And 
> there have been at least three Forth machines, where the hardware itself 
> was designed to support the language's VM.  No microcode at all.
> 
There's Jazelle: http://en.wikipedia.org/wiki/Jazelle.


From python at mrabarnett.plus.com  Thu Jul 30 11:53:35 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 16:53:35 +0100
Subject: Does python have the capability for driver development ?
In-Reply-To: <87vdlate6o.fsf@benfinney.id.au>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>	<mailman.3963.1248960056.8015.python-list@python.org>	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
	<87vdlate6o.fsf@benfinney.id.au>
Message-ID: <4A71C1FF.2070702@mrabarnett.plus.com>

Ben Finney wrote:
> "Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:
> 
>> Machine Code:
>> Whatever the machine executes, it could be that the CPU uses an
>> abstraction of microcode to do this but from the perspective of the
>> user, this is all done in the same 'black box'
> 
> This requires, of course, defining what is the machine. Python bytecode
> targets a virtual machine that is implemented differently for each
> hardware platform.
> 
>> Compiling:
>> Translate words/symbols/mnemonics to machine code, which than can be
>> either loaded, linked and executed by an OS or read and executed by
>> the BIOS.
> 
> Related to the above point, the ?machine code? can just as easily be
> codes for a virtual machine specification. This is the case for the
> bytecode instructions Python gets compiled to.
> 
>> Interpreted:
>> Instructions which can be fed to a previous compiled program that is
>> able to dynamically change its execution and flow without the need to
>> recompile itself.
> 
> This doesn't make much sense to me, I must say.
> 
> I'd say, instead, that a program is interpreted if its instruction are
> dynamically translated to underlying platform instructions at execution
> time. This is the case for the bytecode instructions interpreted by the
> Python virtual machine.
> 
Interpretation doesn't necessarily mean translating to machine code at
execution time. What you're describing is more like JIT.


From python at mrabarnett.plus.com  Thu Jul 30 11:56:23 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 16:56:23 +0100
Subject: Help with Regex for domain names
In-Reply-To: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
Message-ID: <4A71C2A7.90900@mrabarnett.plus.com>

Feyo wrote:
> I'm trying to figure out how to write efficiently write a regex for
> domain names with a particular top level domain. Let's say, I want to
> grab all domain names with country codes .us, .au, and .de.
> 
> I could create three different regexs that would work:
> regex = re.compile(r'[\w\-\.]+\.us)
> regex = re.compile(r'[\w\-\.]+\.au)
> regex = re.compile(r'[\w\-\.]+\.de)
> 
> How would I write one to accommodate all three, or, better yet, to
> accommodate a list of them that I can pass into a method call? Thanks!
 >
regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')

If you have a list of country codes ["us", "au", "de"] then you can
build the regular expression from it:

regex = re.compile(r'[\w\-\.]+\.(?:%s)' % '|'.join(domains))


From keith at nekotaku.com  Thu Jul 30 11:58:56 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 08:58:56 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
Message-ID: <22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>


> What does you full example look like, including the
> cookie-acquisition-stuff?
>
> Diez

I ran them seperately, hoping for a clue as to what my "cookiejar"
was.

The cookie-acquisition stuff returns "screener.ashx?v=151" when I
search with my domain I am interested in. I have tried
urllib2.HTTPCookieProcessor('screener.ashx?v=151') but that failed
with attr has no cookie header.

>From the HTTPCookieProcessor doco, it appears that non-IE browsers
have a cookie file (and example code) but from what I can tell IE uses
a hidden folder. (you can set your location in IE but it appends a
folder "\Temporary Internet Files"  -

From: http://docs.python.org/dev/library/cookielib.html

***
This example illustrates how to open a URL using your Netscape,
Mozilla, or Lynx cookies (assumes Unix/Netscape convention for
location of the cookies file):

import os, cookielib, urllib2
cj = cookielib.MozillaCookieJar()
cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
r = opener.open("http://example.com/")
***

Not sure how to adapt this for IE.


From darkneter at gmail.com  Thu Jul 30 12:06:11 2009
From: darkneter at gmail.com (NighterNet)
Date: Thu, 30 Jul 2009 09:06:11 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<mailman.3966.1248962186.8015.python-list@python.org>
Message-ID: <15017646-6e20-40ff-af70-5717598f26bb@a39g2000pre.googlegroups.com>

On Jul 30, 6:56?am, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
> "NighterNet" <darkne... at gmail.com> wrote in message
>
> news:55aba832-df6d-455f-bf34-04d37eb061cd at i4g2000prm.googlegroups.com...
>
> >I am trying to figure out how to send text or byte in python3.1. I am
> > trying to send data to flashsocketto get there. I am not sure how to
> > work it.
>
> > buff= 'id=' , self.id , ':balive=False\n'
> > clientSock.send(buff);
> > --
> >http://mail.python.org/mailman/listinfo/python-list
>
> Python3.1strings are Unicode (think characters not bytes). ?When writing
> to files, sockets, etc. bytes must be used. ?Unicode strings have an
> encode() method, where you can specify an appropriate encoding (ascii,
> latin-1, windows-1252, utf-8, etc.):
>
> ? ? clientSock.send(buff.encode('ascii'))
>
> When reading from thesocket, you can decode() the byte strings back into
> Unicode strings.
>
> ? ? data = clientSock.recv(1024).decode('ascii')
>
> -Mark

I am not sure how to use struct package.
Here an example for the input:
{id:1,playername:guest,x:100,y:50}
{id:2,playername:tester,x:100,y:50}

struct.pack(? )


From cjw at ncf.ca  Thu Jul 30 12:18:07 2009
From: cjw at ncf.ca (Colin J. Williams)
Date: Thu, 30 Jul 2009 12:18:07 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <h4sh41$fu7$1@theodyn.ncf.ca>

Some have treated this as a troll.  I don't.
r wrote:
[snip]

> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.
> 
+1
> 2.) the .each method
> container.each{|localVar| block}
> This method can really cleanup some ugly for loops, although i really
> like the readability of for loops.
> 
Not clear.
> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max(). You know what i am talking about here people. We
> all get complacent and It seems easier to just cope with these
> problems instead of fighting for change. But look at the French,  WHAT
> THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!
> 
+0.6
or better [1, 2, 3, 4, 5].len or [1, 2, 3, 4, 5].max

What has this got to do with "true OOP"?

[snip]


From deets at nospam.web.de  Thu Jul 30 12:23:59 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Thu, 30 Jul 2009 18:23:59 +0200
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
Message-ID: <7ddvp0F2brmgrU1@mid.uni-berlin.de>

KB wrote:

> 
>> What does you full example look like, including the
>> cookie-acquisition-stuff?
>>
>> Diez
> 
> I ran them seperately, hoping for a clue as to what my "cookiejar"
> was.
> 
> The cookie-acquisition stuff returns "screener.ashx?v=151" when I
> search with my domain I am interested in. I have tried
> urllib2.HTTPCookieProcessor('screener.ashx?v=151') but that failed
> with attr has no cookie header.
> 
> From the HTTPCookieProcessor doco, it appears that non-IE browsers
> have a cookie file (and example code) but from what I can tell IE uses
> a hidden folder. (you can set your location in IE but it appends a
> folder "\Temporary Internet Files"  -
> 
> From: http://docs.python.org/dev/library/cookielib.html
> 
> ***
> This example illustrates how to open a URL using your Netscape,
> Mozilla, or Lynx cookies (assumes Unix/Netscape convention for
> location of the cookies file):
> 
> import os, cookielib, urllib2
> cj = cookielib.MozillaCookieJar()
> cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
> opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
> r = opener.open("http://example.com/")
> ***
> 
> Not sure how to adapt this for IE.

You could create a file that resembles the cookies.txt - no idea how that
looks, but I guess it's pretty simple. 

Diez


From ethan at stoneleaf.us  Thu Jul 30 12:27:32 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 30 Jul 2009 09:27:32 -0700
Subject: Does python have the capability for driver development ?
In-Reply-To: <87vdlate6o.fsf@benfinney.id.au>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<4a7151b2$0$17782$ba4acef3@news.orange.fr>	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com>	<mailman.3963.1248960056.8015.python-list@python.org>	<uNSdnbdg1pPiPuzXnZ2dnUVZ8t2dnZ2d@bt.com>
	<87vdlate6o.fsf@benfinney.id.au>
Message-ID: <4A71C9F4.8040006@stoneleaf.us>

Ben Finney wrote:
> "Martin P. Hellwig" <martin.hellwig at dcuktec.org> writes:
> 
> 
>>Machine Code:
>>Whatever the machine executes, it could be that the CPU uses an
>>abstraction of microcode to do this but from the perspective of the
>>user, this is all done in the same 'black box'
> 
> 
> This requires, of course, defining what is the machine. Python bytecode
> targets a virtual machine that is implemented differently for each
> hardware platform.
> 
> 
>>Compiling:
>>Translate words/symbols/mnemonics to machine code, which than can be
>>either loaded, linked and executed by an OS or read and executed by
>>the BIOS.
> 
> 
> Related to the above point, the ?machine code? can just as easily be
> codes for a virtual machine specification. This is the case for the
> bytecode instructions Python gets compiled to.
> 
> 
>>Interpreted:
>>Instructions which can be fed to a previous compiled program that is
>>able to dynamically change its execution and flow without the need to
>>recompile itself.
> 
> 
> This doesn't make much sense to me, I must say.
> 
> I'd say, instead, that a program is interpreted if its instruction are
> dynamically translated to underlying platform instructions at execution
> time. This is the case for the bytecode instructions interpreted by the
> Python virtual machine.
> 

I would have said compiled is executed by hardware, interpreted is 
executed by software -- but I like your definition better.  :)

~Ethan~


From garrickp at gmail.com  Thu Jul 30 12:31:22 2009
From: garrickp at gmail.com (Falcolas)
Date: Thu, 30 Jul 2009 09:31:22 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>

On Jul 29, 9:06?pm, r <rt8... at gmail.com> wrote:

> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.

I personally would not prefer this, and would likely continue to use
(), precisely for code clarity - let me explain:

foo.nextval
foo.val
foo.previousval

Which of the calls above referenced instance variables, and which ones
called functions which changed the internal state of foo? I would have
trouble saying, just based on the calls above. I would have to go back
to the definition or documentation of foo to identify which is doing
what. On the other hand, the following gives a better clue as to what
is happening (granted not perfect, but better):

foo.nextval()
foo.val
foo.previousval()

~G


From keith at nekotaku.com  Thu Jul 30 12:31:33 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 09:31:33 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
	<7ddvp0F2brmgrU1@mid.uni-berlin.de>
Message-ID: <33b7685b-054a-442c-8e97-46a5b77f7900@z4g2000prh.googlegroups.com>

On Jul 30, 9:23?am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> KB wrote:
>
> >> What does you full example look like, including the
> >> cookie-acquisition-stuff?
>
> >> Diez
>
> > I ran them seperately, hoping for a clue as to what my "cookiejar"
> > was.
>
> > The cookie-acquisition stuff returns "screener.ashx?v=151" when I
> > search with my domain I am interested in. I have tried
> > urllib2.HTTPCookieProcessor('screener.ashx?v=151') but that failed
> > with attr has no cookie header.
>
> > From the HTTPCookieProcessor doco, it appears that non-IE browsers
> > have a cookie file (and example code) but from what I can tell IE uses
> > a hidden folder. (you can set your location in IE but it appends a
> > folder "\Temporary Internet Files" ?-
>
> > From:http://docs.python.org/dev/library/cookielib.html
>
> > ***
> > This example illustrates how to open a URL using your Netscape,
> > Mozilla, or Lynx cookies (assumes Unix/Netscape convention for
> > location of the cookies file):
>
> > import os, cookielib, urllib2
> > cj = cookielib.MozillaCookieJar()
> > cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
> > opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
> > r = opener.open("http://example.com/")
> > ***
>
> > Not sure how to adapt this for IE.
>
> You could create a file that resembles the cookies.txt - no idea how that
> looks, but I guess it's pretty simple.
>
> Diez- Hide quoted text -
>
> - Show quoted text -

Yeah unfortunately I just tried Firefox and it uses cookies.sqlite
now... more dead ends :)


From edreamleo at charter.net  Thu Jul 30 12:45:32 2009
From: edreamleo at charter.net (Edward K Ream)
Date: Thu, 30 Jul 2009 11:45:32 -0500
Subject: ANN: Leo 4.6.1 final released
Message-ID: <e8kcm.21745$yP1.19646@newsfe01.iad>

Leo 4.6.1 final is now available at:
http://sourceforge.net/project/showfiles.php?group_id=3458&package_id=29106

Leo is a text editor, data organizer, project manager and much more. See:
http://webpages.charter.net/edreamleo/intro.html

Leo 4.6.1 fixes several minor bugs in Leo 4.6.

The highlights of Leo 4.6
--------------------------
- Cached external files *greatly* reduces the time to load .leo files.
- Leo now features a modern Qt interface by default.
  Leo's legacy Tk interface can also be used.
- New --config, --file and --gui command-line options.
- Leo tests syntax of .py files when saving them.
- Leo can now open any kind of file into @edit nodes.
- @auto-rst nodes allow easy editing of reStructuredText files.
- Properties of commanders, positions and nodes simplify programming.
- Improved Leo's unit testing framework.
- Leo now requires Python 2.5 or later.
- Dozens of small improvements and bug fixes.

Links:
------
Leo:      http://webpages.charter.net/edreamleo/front.html
Forum:    http://groups.google.com/group/leo-editor
Download: http://sourceforge.net/project/showfiles.php?group_id=3458
Bzr:      http://code.launchpad.net/leo-editor/
Quotes:   http://webpages.charter.net/edreamleo/testimonials.html
--------------------------------------------------------------------
Edward K. Ream   email:  edreamleo at yahoo.com
Leo: http://webpages.charter.net/edreamleo/front.html
--------------------------------------------------------------------




From inky788 at gmail.com  Thu Jul 30 13:01:40 2009
From: inky788 at gmail.com (Inky 788)
Date: Thu, 30 Jul 2009 10:01:40 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
Message-ID: <196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>

On Jul 30, 12:04?am, alex23 <wuwe... at gmail.com> wrote:
> On Jul 30, 1:06?pm, r <rt8... at gmail.com> wrote:
>
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> How do you distinguish between calling a method with no arguments, and
> getting access to the method object itself (because it _is_ an object,
> y'know, it's OO all the way down...)?

I agree with alex here. Will take the explicit syntax over the extra
cognitive load of figuring out exactly what's going on with
`obj.m1.m2.m3`.

Python has its warts, but requiring ()'s on function calls isn't one
of them. :)


From bieffe62 at gmail.com  Thu Jul 30 13:03:42 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Thu, 30 Jul 2009 10:03:42 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<mailman.3966.1248962186.8015.python-list@python.org>
	<15017646-6e20-40ff-af70-5717598f26bb@a39g2000pre.googlegroups.com>
Message-ID: <3b14ad80-2e0e-4d4f-92e7-684dc75a7a05@w41g2000yqb.googlegroups.com>

On 30 Lug, 18:06, NighterNet <darkne... at gmail.com> wrote:
> On Jul 30, 6:56?am, "Mark Tolonen" <metolone+gm... at gmail.com> wrote:
>
>
>
>
>
> > "NighterNet" <darkne... at gmail.com> wrote in message
>
> >news:55aba832-df6d-455f-bf34-04d37eb061cd at i4g2000prm.googlegroups.com...
>
> > >I am trying to figure out how to send text or byte in python3.1. I am
> > > trying to send data to flashsocketto get there. I am not sure how to
> > > work it.
>
> > > buff= 'id=' , self.id , ':balive=False\n'
> > > clientSock.send(buff);
> > > --
> > >http://mail.python.org/mailman/listinfo/python-list
>
> > Python3.1strings are Unicode (think characters not bytes). ?When writing
> > to files, sockets, etc. bytes must be used. ?Unicode strings have an
> > encode() method, where you can specify an appropriate encoding (ascii,
> > latin-1, windows-1252, utf-8, etc.):
>
> > ? ? clientSock.send(buff.encode('ascii'))
>
> > When reading from thesocket, you can decode() the byte strings back into
> > Unicode strings.
>
> > ? ? data = clientSock.recv(1024).decode('ascii')
>
> > -Mark
>
> I am not sure how to use struct package.
> Here an example for the input:
> {id:1,playername:guest,x:100,y:50}
> {id:2,playername:tester,x:100,y:50}
>
> struct.pack(? )

If your messages are ASCII, like it seems, forget about struct, which
is for 'binary' message format.
Format the string as you would in 2.6 ( using % or string.format for
instance ) and then use encode
as instructed.




From davea at dejaviewphoto.com  Thu Jul 30 13:07:43 2009
From: davea at dejaviewphoto.com (Dave Angel)
Date: Thu, 30 Jul 2009 13:07:43 -0400
Subject: Run pyc file without specifying python path ?
In-Reply-To: <7F0503CD69378F49BE0DC30661C6CCF6701A26D2@enbmail01.lsi.com>
References: <mailman.44.1248861603.12188.python-list@python.org>	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26D2@enbmail01.lsi.com>
Message-ID: <4A71D35F.3090800@dejaviewphoto.com>

Barak, Ron wrote:
> Hi Dave,
>
> On second thoughts, I may have a problem implementing the wrapper solution, because my actual test_pyc.pyc, needs to parse its command line.
> Namely, the actual call to test_pyc.pyc looks something like this:
>
> $ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t tvn -p pool1 -l -c
>
> And I don't know of a way to add these parameters to the "import  test_pyc" in wrapper
>
> Is there a way to pass information to an imported module ? (Sorry if there's an obvious answer, I just cannot figure it out).
>
> Bye,
> Ron.
>
>   
>> -----Original Message-----
>> From: Dave Angel [mailto:davea at dejaviewphoto.com] 
>> Sent: Thursday, July 30, 2009 16:03
>> To: Barak, Ron
>> Cc: 'Dave Angel'; 'python-list at python.org'
>> Subject: RE: Run pyc file without specifying python path ?
>>
>> Barak, Ron wrote:
>>     
>>>> -----Original Message-----
>>>> From: Dave Angel [mailto:davea at ieee.org]
>>>> Sent: Wednesday, July 29, 2009 21:05
>>>> To: Barak, Ron
>>>> Cc: 'python-list at python.org'
>>>> Subject: Re: Run pyc file without specifying python path ?
>>>>
>>>> Barak, Ron wrote:
>>>>     
>>>>         
>>>>> Hi,
>>>>>
>>>>> I wanted to make a python byte-code file executable,
>>>>>       
>>>>>           
>>>> expecting to be able to run it without specifying "python" on the 
>>>> (Linux bash) command line.
>>>>     
>>>>         
>>>>> So, I wrote the following:
>>>>>
>>>>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
>>>>>
>>>>> print "hello"
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> and made its pyc file executable:
>>>>>
>>>>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
>>>>> 4 -rwxr-xr-x  1 root root 106 Jul 29 14:22 test_pyc.pyc
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> So, I see:
>>>>>
>>>>> [root at VMLinux1 python]# file test_pyc.py*
>>>>> test_pyc.py:  a python script text executable
>>>>> test_pyc.pyc: python 2.3 byte-compiled
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> If I try to do the following, no problem:
>>>>>
>>>>> [root at VMLinux1 python]# python test_pyc.pyc hello
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> However, the following fails:
>>>>>
>>>>> [root at VMLinux1 python]# ./test_pyc.pyc
>>>>> -bash: ./test_pyc.pyc: cannot execute binary file
>>>>> [root at VMLinux1 python]#
>>>>>
>>>>> Is there a way to run a pyc file without specifying the
>>>>>       
>>>>>           
>>>> python path ?
>>>>     
>>>>         
>>>>> Bye,
>>>>> Ron.
>>>>>
>>>>>   
>>>>>       
>>>>>           
>>>> I don't currently run Unix, but I think I know the problem.
>>>>
>>>> In a text file, the shell examines the first line, and if 
>>>>         
>> it begins 
>>     
>>>> #!
>>>> it's assumed to point to the executable of an interpreter for that 
>>>> text file.  Presumably the same trick doesn't work for a .pyc file.
>>>>
>>>> Why not write a trivial wrapper.py file, don't compile it, and let 
>>>> that invoke the main code in the .pyc file?
>>>>
>>>> Then make wrapper.py executable, and you're ready to go.
>>>>
>>>> DaveA
>>>>
>>>>
>>>>     
>>>>         
>>> Hi Dave,
>>> Your solution sort of defeats my intended purpose (sorry 
>>>       
>> for not divulging my 'hidden agenda').
>>     
>>> I wanted my application to "hide" the fact that it's a 
>>>       
>> python script, and look as much as possible like it's a 
>> compiled program.
>>     
>>> The reason I don't just give my user a py file, is that I 
>>>       
>> don't want a cleaver user to change the innards of the script.
>>     
>>> On the other hand, I don't want to make a compiled 
>>>       
>> (freezed?) version of the application, because it'll grow the 
>> resulting file significantly, and I don't have the experience 
>> to know how it will run on different Linuxes.
>>     
>>> Bye,
>>> Ron. 
>>>   
>>>       
>> Most of the other answers basically paraphrased my suggestion 
>> of making a wrapper file, not compiling it, and making it 
>> executable.  With that 
>> approach, the user just types   "wrapper.py" on his command line.
>>
>> And wrapper.py only needs two lines, a shebang, and an 
>> import, no big deal if the user modifies it.  The rest of 
>> your code can be .pyc files.
>>
>> Steven makes some good points.  You have to define what level 
>> of clever you're protecting from.  A determined hacker will 
>> get in no matter what you do, unless you want to ship the 
>> program in a proprietary embedded system, encased in epoxy.  
>> Further, if you have an extension of .py or .pyc, a 
>> knowledgeable hacker will know it's probably python.
>>
>> You imply you want it to run unmodifed on multiple unknown 
>> Linux versions.  I think that lets out binfmt solutions.  
>> That means you need to test and support not only multiple 
>> Linux implementations, but multiple Python versions, because 
>> who knows what the user may have installed.  I think you need 
>> to rethink your support strategy.  And maybe concentrate on 
>> being able to detect change, rather than prevent it.
>>
>> DaveA
>>
>>
>>
>>     
(Please don't top-post.  It puts responses out of order)

You don't have to do anything special.  Any module can import sys, and 
parse sys.argv, as long as it wasn't yet modified.

DaveA


From rt8396 at gmail.com  Thu Jul 30 13:09:02 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:09:02 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
Message-ID: <a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>

On Jul 30, 11:31?am, Falcolas <garri... at gmail.com> wrote:
> On Jul 29, 9:06?pm, r <rt8... at gmail.com> wrote:
>
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> I personally would not prefer this, and would likely continue to use
> (), precisely for code clarity - let me explain:
>
> foo.nextval
> foo.val
> foo.previousval
>
> Which of the calls above referenced instance variables, and which ones
> called functions which changed the internal state of foo? I would have
> trouble saying, just based on the calls above. I would have to go back
> to the definition or documentation of foo to identify which is doing
> what. On the other hand, the following gives a better clue as to what
> is happening (granted not perfect, but better):
>
> foo.nextval()
> foo.val
> foo.previousval()
>
> ~G

I held your exact same view before i learned the Ruby language. And
your veiw makes some good points, however, naming conventions with
eliminate this problem all together. All "method names" should use the
underscore to separate words, "variable names" should use camelCase,
"constants" in all caps, and "class defs" in titlecase.

def go_and_do_this_for_me_now(self, *args)
self.variableNameHere
MyClassNameHere
THISISACONSTANT -or- THIS_IS_A_CONSTANT


in your example i would have used the following

foo.next_value
foo.value
foo.prev_value

good naming conventions will make your life (and everybody else's)
much easier when debugging code.





From masklinn at masklinn.net  Thu Jul 30 13:10:35 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:10:35 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
Message-ID: <AAAD5E08-8E8E-460E-9703-F6C720DBA38B@masklinn.net>

On 30 Jul 2009, at 18:31 , Falcolas wrote:
> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>
>> 1.) No need to use "()" to call a function with no arguments.
>> Python --> "obj.m2().m3()" --ugly
>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>> Man, i must admit i really like this, and your code will look so much
>> cleaner.
>
> I personally would not prefer this, and would likely continue to use
> (), precisely for code clarity - let me explain:
>
> foo.nextval
> foo.val
> foo.previousval
>
> Which of the calls above referenced instance variables
Well, that's very simple: none of them. In Ruby (as in Smalltalk),  
public instance variables simply don't exist.

> and which ones called functions which changed the internal state of  
> foo?
That you can't say, but neither can you say in Python as they could  
all be properties. And of course just because it's a method doesn't  
mean it mutates the object.

> I would have
> trouble saying, just based on the calls above. I would have to go back
> to the definition or documentation of foo to identify which is doing
> what. On the other hand, the following gives a better clue as to what
> is happening (granted not perfect, but better):
Well... it doesn't give much of a clue no really.


From masklinn at masklinn.net  Thu Jul 30 13:15:14 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:15:14 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
Message-ID: <F3EE917F-FF02-429C-828A-977623E23C60@masklinn.net>

On 30 Jul 2009, at 19:01 , Inky 788 wrote:
> On Jul 30, 12:04 am, alex23 <wuwe... at gmail.com> wrote:
>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>
>>> 1.) No need to use "()" to call a function with no arguments.
>>> Python --> "obj.m2().m3()" --ugly
>>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>>> Man, i must admit i really like this, and your code will look so  
>>> much
>>> cleaner.
>>
>> How do you distinguish between calling a method with no arguments,  
>> and
>> getting access to the method object itself (because it _is_ an  
>> object,
>> y'know, it's OO all the way down...)?
>
> I agree with alex here. Will take the explicit syntax over the extra
> cognitive load of figuring out exactly what's going on with
> `obj.m1.m2.m3`.
There's no cognitive load whatsoever: it's calling methods. Always.  
Ruby simply gives you no other option. Now it could be very simple  
methods to instance attributes, akin to a java getter, but it's still  
only methods.

Furthermore Ruby has a pretty nice convention (sadly not used enough I  
think) taken from Scheme where it's possible to postfix a method name  
with "!" (note: the "!" is part of the name, there's no magic) to  
indicate that this method modifies the object it's called on rather  
than simply returning stuff.



From keith at nekotaku.com  Thu Jul 30 13:16:45 2009
From: keith at nekotaku.com (KB)
Date: Thu, 30 Jul 2009 10:16:45 -0700 (PDT)
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
	<7ddvp0F2brmgrU1@mid.uni-berlin.de>
	<33b7685b-054a-442c-8e97-46a5b77f7900@z4g2000prh.googlegroups.com>
Message-ID: <f2d69d68-66be-4e35-ae04-afe8f5ab625c@l5g2000pra.googlegroups.com>

Winner, winner, chicken dinner... resolved.

http://wwwsearch.sourceforge.net/mechanize/doc.html

import mechanize
cj = mechanize.MSIECookieJar(delayload=True)
cj.load_from_registry()  # finds cookie index file from registry

Thanks Mr Lee!


From mhanbali at teksystems.com  Thu Jul 30 13:22:20 2009
From: mhanbali at teksystems.com (Mehdi H)
Date: Thu, 30 Jul 2009 10:22:20 -0700 (PDT)
Subject: NASA using Python / Django for NEBULA (cloud comp.)
Message-ID: <57859e1d-ff69-49fc-b758-1331912b4d0e@v36g2000yqv.googlegroups.com>

Hello Python devs!

I'm supporting NASA on their NEBULA project and they're looking for
Python / Django experts to join their team here in Mountain View, CA.

If you're interested, let me know and we can talk more on how they're
using Django in their environment!


Thanks,
Mehdi




From robert.kern at gmail.com  Thu Jul 30 13:24:52 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 30 Jul 2009 12:24:52 -0500
Subject: Pyplot
In-Reply-To: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
References: <8fa7fe790907300202s66bde801k254c3fab10515f50@mail.gmail.com>
Message-ID: <h4sl14$q20$1@ger.gmane.org>

On 2009-07-30 04:02, Kaan AK??T wrote:
> I am a newbee in Python. I have some problem with usage of Pyplot. I
> have a loop that creates plot in every end of it. Problem starts here:
> The first plot is fine but the second one is plotted onto the first
> plot. I use:
>
> plt.cla()
> plt.draw()
> plt.hold(False)
> plt.close()
> plt.clf()
>
> but nothing works. Perhaps I am having a problem with basics, please
> help me if you know something about it.

Create a new window by using figure().

You will want to ask matplotlib questions on the matplotlib mailing list:

   https://lists.sourceforge.net/lists/listinfo/matplotlib-users

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From dkatkowski at gmail.com  Thu Jul 30 13:25:58 2009
From: dkatkowski at gmail.com (Feyo)
Date: Thu, 30 Jul 2009 10:25:58 -0700 (PDT)
Subject: Help with Regex for domain names
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
	<mailman.3973.1248969388.8015.python-list@python.org>
Message-ID: <78504224-b114-45f3-a302-95fbd8393443@o6g2000yqj.googlegroups.com>

On Jul 30, 11:56?am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Feyo wrote:
> > I'm trying to figure out how to write efficiently write a regex for
> > domain names with a particular top level domain. Let's say, I want to
> > grab all domain names with country codes .us, .au, and .de.
>
> > I could create three different regexs that would work:
> > regex = re.compile(r'[\w\-\.]+\.us)
> > regex = re.compile(r'[\w\-\.]+\.au)
> > regex = re.compile(r'[\w\-\.]+\.de)
>
> > How would I write one to accommodate all three, or, better yet, to
> > accommodate a list of them that I can pass into a method call? Thanks!
>
> ?>
> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')
>
> If you have a list of country codes ["us", "au", "de"] then you can
> build the regular expression from it:
>
> regex = re.compile(r'[\w\-\.]+\.(?:%s)' % '|'.join(domains))

Perfect! Thanks.


From rt8396 at gmail.com  Thu Jul 30 13:28:44 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:28:44 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com> 
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com> 
	<mailman.3976.1248974120.8015.python-list@python.org>
Message-ID: <19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>

On Jul 30, 12:15?pm, Masklinn <maskl... at masklinn.net> wrote:
[snip]
> Furthermore Ruby has a pretty nice convention (sadly not used enough I ?
> think) taken from Scheme where it's possible to postfix a method name ?
> with "!" (note: the "!" is part of the name, there's no magic) to ?
> indicate that this method modifies the object it's called on rather ?
> than simply returning stuff.

Another oddity i did not like at first but must admit is growing on me
  vector.reverse --> returns a new reversed vector
  vector.reverse! --> modifies the instance vector in-place

Of course in python you would do...
  vector.reverse --> in-place
  vector.reversed --> in-place

The above example works pretty good, but this doesn't always "sound"
good. Take for example this...
  point3d.offset --> return a new pt
  point3d.offseted --> What did you say!?!?!

Now try Ruby's way
  point3d.offset!
  point3d.offset

a symbol works better for these things


From rurpy at yahoo.com  Thu Jul 30 13:29:09 2009
From: rurpy at yahoo.com (rurpy at yahoo.com)
Date: Thu, 30 Jul 2009 10:29:09 -0700 (PDT)
Subject: Help with Regex for domain names
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
	<mailman.3973.1248969388.8015.python-list@python.org>
Message-ID: <0422bf8f-ce59-4de2-a1a4-b16a32e5f152@o15g2000yqm.googlegroups.com>

On Jul 30, 9:56 am, MRAB <pyt... at mrabarnett.plus.com> wrote:
> Feyo wrote:
> > I'm trying to figure out how to write efficiently write a regex for
> > domain names with a particular top level domain. Let's say, I want to
> > grab all domain names with country codes .us, .au, and .de.
>
> > I could create three different regexs that would work:
> > regex = re.compile(r'[\w\-\.]+\.us)
> > regex = re.compile(r'[\w\-\.]+\.au)
> > regex = re.compile(r'[\w\-\.]+\.de)
>
> > How would I write one to accommodate all three, or, better yet, to
> > accommodate a list of them that I can pass into a method call? Thanks!
>
>  >
> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')

You might also want to consider that some country
codes such as "co" for Columbia might match more than
you want, for example:

  re.match(r'[\w\-\.]+\.(?:us|au|de|co)', 'foo.boo.com')

will match.


From torriem at gmail.com  Thu Jul 30 13:30:03 2009
From: torriem at gmail.com (Michael Torrie)
Date: Thu, 30 Jul 2009 11:30:03 -0600
Subject: Does python have the capability for driver development ?
In-Reply-To: <94abbddc-dac7-4215-84d1-d4eb3f82724d@h21g2000yqa.googlegroups.com>
References: <fe7f675b-a1bc-49cd-993d-6618884ee893@h31g2000yqd.googlegroups.com>	<DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>	<87skgf83ua.fsf@rsw.digi.com.br>
	<mailman.3929.1248911448.8015.python-list@python.org>
	<94abbddc-dac7-4215-84d1-d4eb3f82724d@h21g2000yqa.googlegroups.com>
Message-ID: <4A71D89B.6030301@gmail.com>

MalC0de wrote:
> please introduce me some resource for system programming, I know that
> python is very well at system programming level.
> thanks

Although it is possible (as others have said) to embed Python the
interpreter into a driver, no one has done that that I know of.  You'd
have to write the driver in C or C++, though, and then provide embed a
python interpreter and then provide a python interface (wrapper code
written in C++) that would expose binary primitives and structures to
python that the OS and driver use.  Sounds like quite an undertaking.  I
embedded a python interpreter in a gina dll once (to write login code in
python).  That's a form of system programming, but not what you're
asking about.

Someone years ago someone embedded the perl interpreter into a Linux
driver allowing some kinds of device drivers to be written in perl.  It
was made more as a curiosity though.

Python is not well-suited to system programming.  It takes extra work
(via the ctypes library or other wrappers) to interface with C structs,
plus calls all have to be marshalled to and from the native C APIs.
Might be cool, though.

System programming in Win32 is very complicated and messy.  What little
system programming I've done in Linux was a dream compared.  Definitely
you'll have to master win32 system programming in C and C++ before you
try to embed python in anything.  I'm sure there are a number of books
on the subject.  That's where I'd start.


From rt8396 at gmail.com  Thu Jul 30 13:33:38 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:33:38 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com> 
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com> 
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
Message-ID: <c87549b5-59d2-4136-988a-7c448750e505@d32g2000yqh.googlegroups.com>

Traceback (most recent post last):
  File "<Confessions of a Python Fanboy>", lines (13,14), in <post>
    vector.reverse --> in-place
    vector.reversed --> in-place
DumbMistakeError:

Of course in python you would do...
  vector.reverse --> in-place
  vector.reversed --> new vector


From jeanmichel at sequans.com  Thu Jul 30 13:37:00 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Thu, 30 Jul 2009 19:37:00 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
Message-ID: <4A71DA3C.7060502@sequans.com>

r wrote:
> On Jul 30, 11:31 am, Falcolas <garri... at gmail.com> wrote:
>   
>> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>>
>>     
>>> 1.) No need to use "()" to call a function with no arguments.
>>> Python --> "obj.m2().m3()" --ugly
>>>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
>>> Man, i must admit i really like this, and your code will look so much
>>> cleaner.
>>>       
>> I personally would not prefer this, and would likely continue to use
>> (), precisely for code clarity - let me explain:
>>
>> foo.nextval
>> foo.val
>> foo.previousval
>>
>> Which of the calls above referenced instance variables, and which ones
>> called functions which changed the internal state of foo? I would have
>> trouble saying, just based on the calls above. I would have to go back
>> to the definition or documentation of foo to identify which is doing
>> what. On the other hand, the following gives a better clue as to what
>> is happening (granted not perfect, but better):
>>
>> foo.nextval()
>> foo.val
>> foo.previousval()
>>
>> ~G
>>     
>
> I held your exact same view before i learned the Ruby language. And
> your veiw makes some good points, however, naming conventions with
> eliminate this problem all together. All "method names" should use the
> underscore to separate words, "variable names" should use camelCase,
> "constants" in all caps, and "class defs" in titlecase.
>
> def go_and_do_this_for_me_now(self, *args)
> self.variableNameHere
> MyClassNameHere
> THISISACONSTANT -or- THIS_IS_A_CONSTANT
>
>
> in your example i would have used the following
>
> foo.next_value
> foo.value
> foo.prev_value
>
> good naming conventions will make your life (and everybody else's)
> much easier when debugging code.
>
>
>
>   
How do I know if foo.value is an attribute or if it is a method that 
returns the foo value ? It seems you can make the difference only when 
tokens are composed of more than one word, not very handy don't you think ?

Just feeding the troll.

JM



From carsten.haese at gmail.com  Thu Jul 30 13:42:30 2009
From: carsten.haese at gmail.com (Carsten Haese)
Date: Thu, 30 Jul 2009 13:42:30 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
Message-ID: <h4sm27$u5j$1@ger.gmane.org>

r wrote:
> Of course in python you would do...
>   vector.reverse --> in-place
>   vector.reversed --> in-place

You do know that only one of those works in-place, right?

> The above example works pretty good, but this doesn't always "sound"
> good. Take for example this...
>   point3d.offset --> return a new pt
>   point3d.offseted --> What did you say!?!?!
> 
> Now try Ruby's way
>   point3d.offset!
>   point3d.offset
> 
> a symbol works better for these things

Or you could use a better verb:

point3d.move -> modifies in place
point3d.moved -> returns a new point

-Carsten



From rt8396 at gmail.com  Thu Jul 30 13:45:49 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 10:45:49 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com> 
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com> 
	<mailman.3979.1248975429.8015.python-list@python.org>
Message-ID: <91508ea6-a9dd-4d80-81e6-c056c26aae5c@b15g2000yqd.googlegroups.com>

On Jul 30, 12:37?pm, Jean-Michel Pichavant <jeanmic... at sequans.com>
wrote:
> r wrote:
> > On Jul 30, 11:31 am, Falcolas <garri... at gmail.com> wrote:
>
> >> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>
> >>> 1.) No need to use "()" to call a function with no arguments.
> >>> Python --> "obj.m2().m3()" --ugly
> >>> ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> >>> Man, i must admit i really like this, and your code will look so much
> >>> cleaner.
>
> >> I personally would not prefer this, and would likely continue to use
> >> (), precisely for code clarity - let me explain:
>
> >> foo.nextval
> >> foo.val
> >> foo.previousval
>
> >> Which of the calls above referenced instance variables, and which ones
> >> called functions which changed the internal state of foo? I would have
> >> trouble saying, just based on the calls above. I would have to go back
> >> to the definition or documentation of foo to identify which is doing
> >> what. On the other hand, the following gives a better clue as to what
> >> is happening (granted not perfect, but better):
>
> >> foo.nextval()
> >> foo.val
> >> foo.previousval()
>
> >> ~G
>
> > I held your exact same view before i learned the Ruby language. And
> > your veiw makes some good points, however, naming conventions with
> > eliminate this problem all together. All "method names" should use the
> > underscore to separate words, "variable names" should use camelCase,
> > "constants" in all caps, and "class defs" in titlecase.
>
> > def go_and_do_this_for_me_now(self, *args)
> > self.variableNameHere
> > MyClassNameHere
> > THISISACONSTANT -or- THIS_IS_A_CONSTANT
>
> > in your example i would have used the following
>
> > foo.next_value
> > foo.value
> > foo.prev_value
>
> > good naming conventions will make your life (and everybody else's)
> > much easier when debugging code.
>
> How do I know if foo.value is an attribute or if it is a method that
> returns the foo value ? It seems you can make the difference only when
> tokens are composed of more than one word, not very handy don't you think ?
>
> Just feeding the troll.
>
> JM

You can still use empty parenthesis in Ruby if that floats your boat.

obj.method() <-- note the empty parenthesis

I am just saying don't make them mandatory, thats all. In any case
where ambiguity abounds, by all means use the damn parenthisis.

Now Ruby will even let you call a method *that has arguments* with no
parenthisis -- however, i do not think this is a good idea. Consider
the following

  Geom::Transformation.rotation pt, vec, ang
  bad coder!, bad!
  ...and leads to worn out eyeball parsers in a hurry

  Geom::Transformation.rotation(pt, vec, ang)
  yes, good boy!




From kyosohma at gmail.com  Thu Jul 30 13:45:57 2009
From: kyosohma at gmail.com (Mike Driscoll)
Date: Thu, 30 Jul 2009 10:45:57 -0700 (PDT)
Subject: Bug in IEHtmlWindow?
References: <8a5ed753-d437-45a6-8fee-300eea1207ca@c2g2000yqi.googlegroups.com>
Message-ID: <b48c3835-490b-4434-b74a-8c4449f8cd4a@n11g2000yqb.googlegroups.com>

On Jul 30, 2:54?am, Massi <massi_... at msn.com> wrote:
> Hi everyone, I'm trying to use IEHtmlWindow in my application (python
> 2.5, wxpython 2.8 on win xp). Everything is ok, but I encountered a
> problem which also affects the demo. If I make a research on google a
> strange message appears, saying (I'll try to translate from italian):
>
> Error during execution.
> Do you want to run the debug?
>
> line 29:
> error: 'r' is NULL or it is not an object
>
> Did anybody have the same problem? is it a bug?
> Thanks in advance for your help.

I've never seen that error. Could you re-post to the wxPython user's
list? They can probably help you there: http://groups.google.com/group/wxPython

Mike


From digitig at gmail.com  Thu Jul 30 13:47:04 2009
From: digitig at gmail.com (Tim Rowe)
Date: Thu, 30 Jul 2009 18:47:04 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <aee48b3c0907301047s7a69080epe2228477e9f51610@mail.gmail.com>

2009/7/30 r <rt8396 at gmail.com>:
>
> Like your
> first lay, your first programing language can leave an indelible mark
> on you

That's true. FOCAL scarred me for life.

> but i now realize Ruby has some good
> things going for it.

Any language that gets any sort of real use has to have. For instance,
I love Ada's numeric types (you can specify either the minimum number
of significant figures or the maximum delta for a real type, and it
will give you a type that satisfies that -- or a compilation error if
it can't.  That matches genuine problem domains far better than having
to remember how many bits in a double on this particular system, and
reduces portability bugs).

> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max(). You know what i am talking about here people. We
> all get complacent and It seems easier to just cope with these
> problems instead of fighting for change. But look at the French, ?WHAT
> THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!

I seem to recall recent studies showing that the French were on
average happier than Brits or Americans. Don't knock it!

> As for the rest of Ruby, i am not impressed. The redundant usage of
> "end" over indention perplexes me. The Perlish feel of "require" and
> the horrifically cryptic idioms of Ruby regular expressions. The
> "puts" and "gets" seem childish and the math class does not even have
> a degrees or radians function!

The operating system dependency built into the language did it for me.
That and the fact that I couldn't stop laughing for long enough to
learn any more when I read in the Pragmatic Programmer's Guide that
"Ruby, unlike less flexible languages, lets you alter the value of a
constant." Yep, as they say "Bug" = "Undocumented feature"!

-- 
Tim Rowe


From masklinn at masklinn.net  Thu Jul 30 13:56:07 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:56:07 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4A71DA3C.7060502@sequans.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
	<4A71DA3C.7060502@sequans.com>
Message-ID: <EFEC96C0-CA5C-49CA-803B-A2F1CF251CAB@masklinn.net>

On 30 Jul 2009, at 19:37 , Jean-Michel Pichavant wrote:
> r wrote:
>> On Jul 30, 11:31 am, Falcolas <garri... at gmail.com> wrote:
>>
>>> On Jul 29, 9:06 pm, r <rt8... at gmail.com> wrote:
>>>
>>>
>>>> 1.) No need to use "()" to call a function with no arguments.
>>>> Python --> "obj.m2().m3()" --ugly
>>>>  Ruby --> "obj.m1.m2.m3"  -- sweeet!
>>>> Man, i must admit i really like this, and your code will look so  
>>>> much
>>>> cleaner.
>>>>
>>> I personally would not prefer this, and would likely continue to use
>>> (), precisely for code clarity - let me explain:
>>>
>>> foo.nextval
>>> foo.val
>>> foo.previousval
>>>
>>> Which of the calls above referenced instance variables, and which  
>>> ones
>>> called functions which changed the internal state of foo? I would  
>>> have
>>> trouble saying, just based on the calls above. I would have to go  
>>> back
>>> to the definition or documentation of foo to identify which is doing
>>> what. On the other hand, the following gives a better clue as to  
>>> what
>>> is happening (granted not perfect, but better):
>>>
>>> foo.nextval()
>>> foo.val
>>> foo.previousval()
>>>
>>> ~G
>>>
>>
>> I held your exact same view before i learned the Ruby language. And
>> your veiw makes some good points, however, naming conventions with
>> eliminate this problem all together. All "method names" should use  
>> the
>> underscore to separate words, "variable names" should use camelCase,
>> "constants" in all caps, and "class defs" in titlecase.
>>
>> def go_and_do_this_for_me_now(self, *args)
>> self.variableNameHere
>> MyClassNameHere
>> THISISACONSTANT -or- THIS_IS_A_CONSTANT
>>
>>
>> in your example i would have used the following
>>
>> foo.next_value
>> foo.value
>> foo.prev_value
>>
>> good naming conventions will make your life (and everybody else's)
>> much easier when debugging code.
>>
> How do I know if foo.value is an attribute or if it is a method that  
> returns the foo value ?
It cannot be an attribute. Ruby doesn't give access to attributes,  
they're always solely private (as in Smalltalk). Also you shouldn't  
reply to r, he has no idea about what he's talking about.



From masklinn at masklinn.net  Thu Jul 30 13:57:54 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 19:57:54 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <h4sm27$u5j$1@ger.gmane.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<h4sm27$u5j$1@ger.gmane.org>
Message-ID: <92229A0F-EC80-43C7-97B8-8C3636581EDE@masklinn.net>

On 30 Jul 2009, at 19:42 , Carsten Haese wrote:
> r wrote:
>> Of course in python you would do...
>>  vector.reverse --> in-place
>>  vector.reversed --> in-place
>
> You do know that only one of those works in-place, right?
>
Well mostly because the other one doesn't exist (as python has  
`lst.reverse()` but `reversed(lst)`) but he was probably talking  
hypothetically. Or something.


From user at example.net  Thu Jul 30 14:05:53 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 20:05:53 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
Message-ID: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>

r wrote:
> On Jul 30, 12:15 pm, Masklinn <maskl... at masklinn.net> wrote:
> [snip]
> 
>>Furthermore Ruby has a pretty nice convention (sadly not used enough I  
>>think) taken from Scheme where it's possible to postfix a method name  
>>with "!" (note: the "!" is part of the name, there's no magic) to  
>>indicate that this method modifies the object it's called on rather  
>>than simply returning stuff.
> 
> 
> Another oddity i did not like at first but must admit is growing on me
>   vector.reverse --> returns a new reversed vector
>   vector.reverse! --> modifies the instance vector in-place
> 
> Of course in python you would do...
>   vector.reverse --> in-place
>   vector.reversed --> in-place
> 

how to reverse a string in python? must i usa a temp? like:

 >>> s = "ciccio"
 >>> l = list(s)
 >>> l.reverse()
 >>> s = "".join(l)
 >>> s
'oiccic'
 >>>

???

bye



From garrickp at gmail.com  Thu Jul 30 14:06:33 2009
From: garrickp at gmail.com (Falcolas)
Date: Thu, 30 Jul 2009 11:06:33 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com> 
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com> 
	<4A71DA3C.7060502@sequans.com>
	<mailman.3982.1248976579.8015.python-list@python.org>
Message-ID: <776cafad-cfe8-442d-8d40-cab4e5c71d9b@c14g2000yqm.googlegroups.com>

On Jul 30, 11:56?am, Masklinn <maskl... at masklinn.net> wrote:
> On 30 Jul 2009, at 19:37 , Jean-Michel Pichavant wrote:
>
> > r wrote:

> > How do I know if foo.value is an attribute or if it is a method that ?
> > returns the foo value ?
>
> It cannot be an attribute. Ruby doesn't give access to attributes, ?
> they're always solely private (as in Smalltalk). Also you shouldn't ?
> reply to r, he has no idea about what he's talking about.

That doesn't sound like a feature I would appreciate much, though I am
a big fan of "we're all adults here" programming. Though if they are
all functions, then adding parentheses wouldn't make much difference,
so offering the option of getting rid of them makes sense.

>> I would have
>> trouble saying, just based on the calls above. I would have to go back
>> to the definition or documentation of foo to identify which is doing
>> what. On the other hand, the following gives a better clue as to what
>> is happening (granted not perfect, but better):

> Well... it doesn't give much of a clue no really.

It, with few exceptions, tells me that fetching the value foo.val will
not modify the state of foo. Important stuff, at least to me.


From user at example.net  Thu Jul 30 14:08:36 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 20:08:36 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.3981.1248976469.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
Message-ID: <4a71e1a5$0$40016$4fafbaef@reader3.news.tin.it>

Tim Rowe wrote:
> 2009/7/30 r <rt8396 at gmail.com>:
> 
>>Like your
>>first lay, your first programing language can leave an indelible mark
>>on you
> 
> 
> That's true. FOCAL scarred me for life.
> 
> 
>>but i now realize Ruby has some good
>>things going for it.
> 
> 
> Any language that gets any sort of real use has to have. For instance,
> I love Ada's numeric types (you can specify either the minimum number
> of significant figures or the maximum delta for a real type, and it
> will give you a type that satisfies that -- or a compilation error if
> it can't.  That matches genuine problem domains far better

doesn't the decimal module do some of that too?

bye


From darkneter at gmail.com  Thu Jul 30 14:13:44 2009
From: darkneter at gmail.com (NighterNet)
Date: Thu, 30 Jul 2009 11:13:44 -0700 (PDT)
Subject: class or thread id count
Message-ID: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>

Need some help on doing some bit simple id count. It like every time
it create a class or thread there is id++. Python 3.1

example:
class ClientThread (threading.Thread):
   def __init__(self,clientSocket):
      threading.Thread.__init__(self)
         self.id += 1;

Not sure it how it works.


From python at mrabarnett.plus.com  Thu Jul 30 14:20:11 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 19:20:11 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <4A71E45B.3070009@mrabarnett.plus.com>

superpollo wrote:
> r wrote:
>> On Jul 30, 12:15 pm, Masklinn <maskl... at masklinn.net> wrote:
>> [snip]
>>
>>> Furthermore Ruby has a pretty nice convention (sadly not used enough 
>>> I  think) taken from Scheme where it's possible to postfix a method 
>>> name  with "!" (note: the "!" is part of the name, there's no magic) 
>>> to  indicate that this method modifies the object it's called on 
>>> rather  than simply returning stuff.
>>
>>
>> Another oddity i did not like at first but must admit is growing on me
>>   vector.reverse --> returns a new reversed vector
>>   vector.reverse! --> modifies the instance vector in-place
>>
>> Of course in python you would do...
>>   vector.reverse --> in-place
>>   vector.reversed --> in-place
>>
> 
> how to reverse a string in python? must i usa a temp? like:
> 
>  >>> s = "ciccio"
>  >>> l = list(s)
>  >>> l.reverse()
>  >>> s = "".join(l)
>  >>> s
> 'oiccic'
>  >>>
> 
> ???
> 
Use slicing with a step of -1:

 >>> s = "ciccio"
 >>> s[::-1]
'oiccic'



From masklinn at masklinn.net  Thu Jul 30 14:22:21 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 20:22:21 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <772E43D2-61B0-4C26-AAA3-C1E9785176AF@masklinn.net>

On 30 Jul 2009, at 20:05 , superpollo wrote:
> r wrote:
>> On Jul 30, 12:15 pm, Masklinn <maskl... at masklinn.net> wrote:
>> [snip]
>>> Furthermore Ruby has a pretty nice convention (sadly not used  
>>> enough I  think) taken from Scheme where it's possible to postfix  
>>> a method name  with "!" (note: the "!" is part of the name,  
>>> there's no magic) to  indicate that this method modifies the  
>>> object it's called on rather  than simply returning stuff.
>> Another oddity i did not like at first but must admit is growing on  
>> me
>>  vector.reverse --> returns a new reversed vector
>>  vector.reverse! --> modifies the instance vector in-place
>> Of course in python you would do...
>>  vector.reverse --> in-place
>>  vector.reversed --> in-place
>
> how to reverse a string in python? must i usa a temp? like:
>
> >>> s = "ciccio"
> >>> l = list(s)
> >>> l.reverse()
> >>> s = "".join(l)
> >>> s
> 'oiccic'
> >>>
>
> ???
>
> bye

s = s[::-1]


From masklinn at masklinn.net  Thu Jul 30 14:24:23 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 20:24:23 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <776cafad-cfe8-442d-8d40-cab4e5c71d9b@c14g2000yqm.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<56bb9325-babc-478b-a98c-03d00c48ac5d@24g2000yqm.googlegroups.com>
	<a793bf1d-c2b0-4e89-82b1-b0e9dc80c1e5@r38g2000yqn.googlegroups.com>
	<4A71DA3C.7060502@sequans.com>
	<mailman.3982.1248976579.8015.python-list@python.org>
	<776cafad-cfe8-442d-8d40-cab4e5c71d9b@c14g2000yqm.googlegroups.com>
Message-ID: <EB4CC38B-C038-45F2-BC37-CC87B712C0A2@masklinn.net>

On 30 Jul 2009, at 20:06 , Falcolas wrote:
> On Jul 30, 11:56 am, Masklinn <maskl... at masklinn.net> wrote:
>> On 30 Jul 2009, at 19:37 , Jean-Michel Pichavant wrote:
>>
>>> r wrote:
>
>>> How do I know if foo.value is an attribute or if it is a method that
>>> returns the foo value ?
>>
>> It cannot be an attribute. Ruby doesn't give access to attributes,
>> they're always solely private (as in Smalltalk). Also you shouldn't
>> reply to r, he has no idea about what he's talking about.
>
> That doesn't sound like a feature I would appreciate much, though I am
> a big fan of "we're all adults here" programming. Though if they are
> all functions, then adding parentheses wouldn't make much difference,
> so offering the option of getting rid of them makes sense.
>
That's pretty much it.

>>> I would have
>>> trouble saying, just based on the calls above. I would have to go  
>>> back
>>> to the definition or documentation of foo to identify which is doing
>>> what. On the other hand, the following gives a better clue as to  
>>> what
>>> is happening (granted not perfect, but better):
>
>> Well... it doesn't give much of a clue no really.
>
> It, with few exceptions, tells me that fetching the value foo.val will
> not modify the state of foo. Important stuff, at least to me.
But because of those few exceptions, it really tells you that foo.val  
*probably* doesn't modify the state of foo. Unless you go source- 
diving, you can't know for sure. Only Haskell gives you that kind of  
guarantees (and even then, the code you call could have an unsafe*  
somewhere)


From davea at ieee.org  Thu Jul 30 14:28:11 2009
From: davea at ieee.org (Dave Angel)
Date: Thu, 30 Jul 2009 14:28:11 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <4A71E63B.6080200@ieee.org>

superpollo wrote:
>> <snip>
>
> how to reverse a string in python? must i usa a temp? like:
>
> >>> s = "ciccio"
> >>> l = list(s)
> >>> l.reverse()
> >>> s = "".join(l)
> >>> s
> 'oiccic'
> >>>
>
> ???
>
> bye
>
>
> </div>
>
simply     s = s[::-1]

DaveA



From user at example.net  Thu Jul 30 14:30:45 2009
From: user at example.net (superpollo)
Date: Thu, 30 Jul 2009 20:30:45 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.3985.1248978012.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
	<mailman.3985.1248978012.8015.python-list@python.org>
Message-ID: <4a71e6d6$0$40004$4fafbaef@reader3.news.tin.it>

MRAB wrote:
> superpollo wrote:
...
>> how to reverse a string in python? must i usa a temp? like:
>>
>>  >>> s = "ciccio"
>>  >>> l = list(s)
>>  >>> l.reverse()
>>  >>> s = "".join(l)
>>  >>> s
>> 'oiccic'
>>  >>>
>>
>> ???
>>
> Use slicing with a step of -1:
> 
>  >>> s = "ciccio"
>  >>> s[::-1]
> 'oiccic'

lol

bye


From hniksic at xemacs.org  Thu Jul 30 14:32:10 2009
From: hniksic at xemacs.org (Hrvoje Niksic)
Date: Thu, 30 Jul 2009 20:32:10 +0200
Subject: New implementation of re module
References: <4A6DD6FB.8040609@mrabarnett.plus.com>
	<200907301235.22563.wolfgang@rohdewald.de>
	<4A717E96.3020900@mrabarnett.plus.com>
	<200907301429.07850.wolfgang@rohdewald.de>
	<mailman.3958.1248958592.8015.python-list@python.org>
Message-ID: <87y6q6dnth.fsf@busola.homelinux.net>

MRAB <python at mrabarnett.plus.com> writes:

> So it complains about:
>
>     ++(RE_CHAR*)context->text_ptr
>
> but not about:
>
>     ++info->repeat.count
>
> Does this mean that the gcc compiler thinks that the cast makes it an
> rvalue?

The cast operator does return an rvalue, treating it otherwise used to
be an extension to popular compilers, including ironically gcc.  The
standard-compliant way of writing the above would be:

++ *(RE_CHAR **) &context->text_ptr


From wells at submute.net  Thu Jul 30 14:45:53 2009
From: wells at submute.net (Wells Oliver)
Date: Thu, 30 Jul 2009 13:45:53 -0500
Subject: Sorting dict by value w/ operator.itemgetter- using key name?
Message-ID: <3f1a902d0907301145t2aa559b7ifcb3dc45d9b7a363@mail.gmail.com>

Bit of code:

print sorted(results.items(), key=operator.itemgetter(1))

Would rather use 'H9', which is the name of the key in position 1 like:

print sorted(results.items(), key=operator.itemgetter('H9'))

Obviously that ain't work else I wouldn't be sending this email. Any tips?

-- 
Wells Oliver
wells at submute.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/7236657b/attachment-0001.html>

From nobody at nowhere.com  Thu Jul 30 14:51:23 2009
From: nobody at nowhere.com (Nobody)
Date: Thu, 30 Jul 2009 19:51:23 +0100
Subject: Help with Regex for domain names
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>
	<mailman.3973.1248969388.8015.python-list@python.org>
	<0422bf8f-ce59-4de2-a1a4-b16a32e5f152@o15g2000yqm.googlegroups.com>
Message-ID: <pan.2009.07.30.18.51.22.890000@nowhere.com>

On Thu, 30 Jul 2009 10:29:09 -0700, rurpy wrote:

>> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')
> 
> You might also want to consider that some country
> codes such as "co" for Columbia might match more than
> you want, for example:
> 
>   re.match(r'[\w\-\.]+\.(?:us|au|de|co)', 'foo.boo.com')
> 
> will match.

... so put \b at the end, i.e.:

regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)\b')



From sri_annauni at yahoo.co.in  Thu Jul 30 15:04:09 2009
From: sri_annauni at yahoo.co.in (srinivasan srinivas)
Date: Fri, 31 Jul 2009 00:34:09 +0530 (IST)
Subject: calling obect method
Message-ID: <960855.56660.qm@web7906.mail.in.yahoo.com>

Hi,
I would like to know if i have an object and one of its methods as a string. How to call the method using this string?
For ex
If object is x and string y has one of its method names. 
x.value(y)() ---. Is there a way to do this?

Thanks,
Srini


      See the Web&#39;s breaking stories, chosen by people like you. Check out Yahoo! Buzz. http://in.buzz.yahoo.com/


From rt8396 at gmail.com  Thu Jul 30 15:08:25 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 12:08:25 -0700 (PDT)
Subject: calling obect method
References: <mailman.3990.1248980658.8015.python-list@python.org>
Message-ID: <2e8c5c91-be27-430b-9cad-46a5bff3ee37@26g2000yqk.googlegroups.com>

>>> import math
>>> getattr(math, 'hypot')(3,4)
5.0


From rt8396 at gmail.com  Thu Jul 30 15:14:12 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 12:14:12 -0700 (PDT)
Subject: class or thread id count
References: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>
Message-ID: <f0446213-638e-41de-b2e8-6c35a1f90004@c2g2000yqi.googlegroups.com>

On Jul 30, 1:13?pm, NighterNet <darkne... at gmail.com> wrote:
> Need some help on doing some bit simple id count. It like every time
> it create a class or thread there is id++. Python 3.1
>
> example:
> class ClientThread (threading.Thread):
> ? ?def __init__(self,clientSocket):
> ? ? ? threading.Thread.__init__(self)
> ? ? ? ? ?self.id += 1;
>
> Not sure it how it works.

use a class atrribute

>>> class Person():
	count = 0
	def __init__(self, name, info):
		self.name = name
		self.info = info
		Person.count+=1


>>> p1 = Person('alex23', 'very annoying')
>>> p2 = Person('Guido', 'very intelligent')
>>> p2.count
2
>>> p1.count
2
>>> Person.count
2


From zuo at chopin.edu.pl  Thu Jul 30 15:20:21 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 21:20:21 +0200
Subject: socket send
In-Reply-To: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
Message-ID: <op.uxwan7s3fvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 o 05:52:06 NighterNet <darkneter at gmail.com> wrote:

> I am trying to figure out how to send text or byte in python 3.1. I am
> trying to send data to flash socket to get there. I am not sure how to
> work it.
>
> buff= 'id=' , self.id , ':balive=False\n'
> clientSock.send(buff);

And what is the problem?

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From bdezonia at wisc.edu  Thu Jul 30 15:36:18 2009
From: bdezonia at wisc.edu (BDZ)
Date: Thu, 30 Jul 2009 12:36:18 -0700 (PDT)
Subject: os.path.exists() and Samba shares
Message-ID: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>

Hello. I have written a Python 3.1 script running on Windows that uses
os.path.exists() to connect to network shares. If the various network
shares require different user account and password combos than the
account the script is running under the routine returns false. I need
something like os.samba.path.exists(username,password,path). Does
anyone have a suggestion on how I can accomplish what I need to do in
Python?


From martin at v.loewis.de  Thu Jul 30 15:56:24 2009
From: martin at v.loewis.de (=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=)
Date: Thu, 30 Jul 2009 21:56:24 +0200
Subject: No PyPI search for 3.x compatible packages
In-Reply-To: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
Message-ID: <4a71fae9$0$10471$9b622d9e@news.freenet.de>

Neil Hodgson wrote:
>    There appears to be no way to search PyPI for packages that are
> compatible with Python 3.x. There are classifiers for 'Programming
> Language' including 'Programming Language :: Python :: 3' but that seems
> to be for implementation language since there are so many packages that
> specify C. 

Not at all. The Trove classifiers *always* mean what the package author
wants them to mean. In the specific case of Python :: 3, they should
mean what makes most sense. For an application, it might make most sense
to specify the language it is written in. For a Python library, it
surely would make most sense to specify the Python version it supports -
notice, however, that this is *also* the Python version the library is
written in.

Regards,
Martin


From darkneter at gmail.com  Thu Jul 30 16:09:36 2009
From: darkneter at gmail.com (NighterNet)
Date: Thu, 30 Jul 2009 13:09:36 -0700 (PDT)
Subject: class or thread id count
References: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>
	<f0446213-638e-41de-b2e8-6c35a1f90004@c2g2000yqi.googlegroups.com>
Message-ID: <68b09353-7e30-4df2-8e05-32159b03414a@f20g2000prn.googlegroups.com>

On Jul 30, 12:14?pm, r <rt8... at gmail.com> wrote:
> On Jul 30, 1:13?pm, NighterNet <darkne... at gmail.com> wrote:
>
> > Need some help on doing some bit simple id count. It like every time
> > it create a class orthreadthere is id++. Python 3.1
>
> > example:
> > class ClientThread (threading.Thread):
> > ? ?def __init__(self,clientSocket):
> > ? ? ? threading.Thread.__init__(self)
> > ? ? ? ? ?self.id += 1;
>
> > Not sure it how it works.
>
> use a class atrribute
>
> >>> class Person():
>
> ? ? ? ? count = 0
> ? ? ? ? def __init__(self, name, info):
> ? ? ? ? ? ? ? ? self.name = name
> ? ? ? ? ? ? ? ? self.info = info
> ? ? ? ? ? ? ? ? Person.count+=1
>
> >>> p1 = Person('alex23', 'very annoying')
> >>> p2 = Person('Guido', 'very intelligent')
> >>> p2.count
> 2
> >>> p1.count
> 2
> >>> Person.count
>
> 2

Thanks it work.

class Person():
  count = 0
  def __init__(self, name, info):
      self.name = name
      self.info = info
      Person.count+=1
      self.count = Person.count


From zuo at chopin.edu.pl  Thu Jul 30 16:16:13 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 22:16:13 +0200
Subject: socket send
In-Reply-To: <41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com>
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com>
Message-ID: <op.uxwc9be4fvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 o 12:29:24 Francesco Bochicchio <bieffe62 at gmail.com> wrote:

> On Jul 30, 5:52?am, NighterNet <darkne... at gmail.com> wrote:
>> I am trying to figure out how to send text or byte in python 3.1. I am
>> trying to send data to flash socket to get there. I am not sure how to
>> work it.
>>
>> buff= 'id=' , self.id , ':balive=False\n'
>> clientSock.send(buff);
>
> Try putting a 'b' before the constant string that you want to send:
>
> >>> type(b'123')
> <class 'bytes'>

It's true. In python '...' literals are for strings ('str' type) and
b'...' literals are for binary data (bytes type).

Sockets' send() and recv() need binary data ('bytes' objects).

> or use something like this to convert non constant strings (with only
> ASCII characters) into bytes:

> >>> s = "A non-constant string : %d " % n
> >>> s
> 'A non-constant string : 12 '
> >>> type(s)
> <class 'str'>

What???

'str' type in Python 3.x IS NOT a type of "non-constant" strings and
IS NOT a type of strings "with only ASCII characters"!

'str' type in Python 3.x *is* the type of immutable ('constant') and
Unicode character (Unicode, not only ASCII) strings. It's the same what
'unicode' type in Python 2.x.

'bytes' type objects in Python 3.x are also immutable. They are good
for binary data (also text data encoded to binary data; see below).

'bytearray' type objects are like 'bytes', but mutable (like e. g.
lists).

>>>> b = bytes ( ord(c) for c in s )
>>>> b
> b'A non-constant string : 12 '
>
> You could also use struct.pack , that in python 3.x returns bytes and
> not strings. In this case you need to specify the size of the string
> (extra bytes are zero-filled):
>
> import struct

What for all that weird actions???

* Simply do:

bytes_object = str_object.encode(<encoding>)
or
bytes_object = bytes(str_object, <encoding>)

-- where <encoding> could be e.g. 'ascii', 'utf-8', 'iso-8859-1' etc.;
using the former method, you can omit this argument -> then default
encoding will be used (usualy 'utf-8').

* As easily as that, you can convert bytes to str:

str_object = bytes_object.decode(<encoding>)
or
str_object = str(bytes_object, <encoding>)

* Some examples:

  >>> 'What makes you think she is a witch?'  # it's str
  'What makes you think she is a witch?'
  >>> 'What makes you think she is a witch?'.encode()  # to bytes
  b'What makes you think she is a witch?'
  >>> 'What makes you think she is a witch?'.encode('utf-8')  # to bytes
  b'What makes you think she is a witch?'
  >>> bytes('What makes you think she is a witch?')  # to bytes???
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  TypeError: string argument without an encoding
  >>> bytes('What makes you think she is a witch?', 'ascii')  # to bytes
  b'What makes you think she is a witch?'

  >>> b'What makes you think she is a witch?'.decode()  # to str
  'What makes you think she is a witch?'
  >>> b'What makes you think she is a witch?'.decode('utf-8')  # to str
  'What makes you think she is a witch?'
  >>> str(b'What makes you think she is a witch?', 'utf-8')  # to str
  'What makes you think she is a witch?'
  >>> str(b'What makes you think she is a witch?')  # but not this way
  "b'What makes you think she is a witch?'"
  [^ note this]

Cheers,

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From zuo at chopin.edu.pl  Thu Jul 30 16:23:32 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 22:23:32 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
Message-ID: <op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>

30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:

> On 30 Jul 2009, at 06:04 , alex23 wrote:
>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>> 2.) the .each method
>>> container.each{|localVar| block}
>>> This method can really cleanup some ugly for loops, although i really
>>> like the readability of for loops.
>>
>> map(lambda localVar: <block>, sequence)
>>
>> or:
>>
>> def usefully_named_func(var):
>>    <block>
>>    return var
>>
>> transformed = [usefully_named_func(v) for v in sequence]
>>
> The issue here is of course that `map` and comprehensions are  
> transformations. `#each` exists for effectful iterations (Ruby has  
> `#map` for the map operation). So the intent expressed by `#each` and  
> `map` isn't the same. Furthermore and this is the most problematic  
> limitation of Python here, `lambda` doesn't allow complex  
> transformations due to its restrictions, so one has to switch to named  
> functions which works but isn't sexy (and tends to lower readability  
> imo).

I don't see any real limitation. What's wrong in:

for localVar in container:
     block

And ruby's container.each is very similar to Python's iter()

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From masklinn at masklinn.net  Thu Jul 30 16:41:57 2009
From: masklinn at masklinn.net (Masklinn)
Date: Thu, 30 Jul 2009 22:41:57 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>

On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
> 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
>
>> On 30 Jul 2009, at 06:04 , alex23 wrote:
>>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>>> 2.) the .each method
>>>> container.each{|localVar| block}
>>>> This method can really cleanup some ugly for loops, although i  
>>>> really
>>>> like the readability of for loops.
>>>
>>> map(lambda localVar: <block>, sequence)
>>>
>>> or:
>>>
>>> def usefully_named_func(var):
>>>   <block>
>>>   return var
>>>
>>> transformed = [usefully_named_func(v) for v in sequence]
>>>
>> The issue here is of course that `map` and comprehensions are  
>> transformations. `#each` exists for effectful iterations (Ruby has  
>> `#map` for the map operation). So the intent expressed by `#each`  
>> and `map` isn't the same. Furthermore and this is the most  
>> problematic limitation of Python here, `lambda` doesn't allow  
>> complex transformations due to its restrictions, so one has to  
>> switch to named functions which works but isn't sexy (and tends to  
>> lower readability imo).
>
> I don't see any real limitation. What's wrong in:
>
> for localVar in container:
>    block
>
Well what's wrong with using that rather than `map`, `filter` or a  
list comprehension? (and if you don't see what the limitations of  
`lambda` are, you probably very rarely use it)

> And ruby's container.each is very similar to Python's iter()
>
Uh? not at all?



From tjreedy at udel.edu  Thu Jul 30 16:55:17 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 16:55:17 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <h4t1bj$4ut$1@ger.gmane.org>

superpollo wrote:
> r wrote:

> how to reverse a string in python? must i usa a temp? like:
> 
>  >>> s = "ciccio"
>  >>> l = list(s)
>  >>> l.reverse()
>  >>> s = "".join(l)
>  >>> s
> 'oiccic'
>  >>>
> 
> ???

No.
 >>> ''.join(list(reversed('abc')))
'cba'
 >>> 'abc'[2::-1]
'cba'
 >>> 'abc'[1000000000::-1]
'cba'

Any int >= len(string)-1 will do, so the call to len will usually not be 
necessary.

Needing strings reversed is not common.  More common might be

for char in reversed(somestring): process(char)

Terry Jan Reedy



From rt8396 at gmail.com  Thu Jul 30 17:02:03 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 14:02:03 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com> 
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com> 
	<mailman.3976.1248974120.8015.python-list@python.org>
	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>
	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>
	<mailman.3995.1248987328.8015.python-list@python.org>
Message-ID: <39013d06-e281-4459-bdb2-19831c9526ea@k1g2000yqf.googlegroups.com>

On Jul 30, 3:55?pm, Terry Reedy <tjre... at udel.edu> wrote:
> superpollo wrote:
> > r wrote:
> > how to reverse a string in python? must i usa a temp? like:
[snip]
> Terry Jan Reedy

No "r" never wrote anything like that. reversing a string is RTFM
material, this is basic stuff here! Stop quoting me as saying things i
did not say! I never asked how to reverse a string, "superpollo"
did.


From tjreedy at udel.edu  Thu Jul 30 17:02:20 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 17:02:20 -0400
Subject: Sorting dict by value w/ operator.itemgetter- using key name?
In-Reply-To: <3f1a902d0907301145t2aa559b7ifcb3dc45d9b7a363@mail.gmail.com>
References: <3f1a902d0907301145t2aa559b7ifcb3dc45d9b7a363@mail.gmail.com>
Message-ID: <h4t1oq$4ut$2@ger.gmane.org>

Wells Oliver wrote:
> Bit of code:
> 
> print sorted(results.items(), key=operator.itemgetter(1))
> 
> Would rather use 'H9', which is the name of the key in position 1 like:
> 
> print sorted(results.items(), key=operator.itemgetter('H9'))
> 
> Obviously that ain't work else I wouldn't be sending this email. Any tips?

Suppose namepos=['H9':1,} etc, then itemgetter(namepos['H9'])



From ethan at stoneleaf.us  Thu Jul 30 17:04:21 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Thu, 30 Jul 2009 14:04:21 -0700
Subject: Regexp problem
In-Reply-To: <h4s7pm$rgr$1@adenine.netfront.net>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>	<mailman.3961.1248959276.8015.python-list@python.org>	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>
	<h4s7pm$rgr$1@adenine.netfront.net>
Message-ID: <4A720AD5.1030202@stoneleaf.us>

Marcus Wanner wrote:
> On 7/30/2009 9:32 AM, Beldar wrote:
> 
>> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>>
>>> Beldar wrote:
>>>
>>>> Hi there!
>>>> I have a problem and i'm not very good at regular expressions.
>>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>>> 'something-is-listening', i need to get the something part, use it in
>>>> my code, and then replace the whole 'something-is-listening' for
>>>> another string.
>>>
>>> \w+ will match a word and enclosing it in (...) will capture what was
>>> matched:
>>>
>>>      m = re.search(r"(\w+)-is-listening", text)
>>>      print "Captured '%s'" % m.group(1)
>>>      print "Matched from %d to %d" % (m.start(), m.end())
>>
>>
>> Ok, thank you all, it was very helpful!
> 
> Wow, I really need to learn more about regexp...
> Any tutorials you guys can recommend?
> 
> Marcus

Mastering Regular Expressions
Powerful Techniques for Perl and Other Tools
By Jeffrey E. F. Friedl

Great book!

~Ethan~


From python at mrabarnett.plus.com  Thu Jul 30 17:28:55 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 22:28:55 +0100
Subject: Help with Regex for domain names
In-Reply-To: <pan.2009.07.30.18.51.22.890000@nowhere.com>
References: <f572d896-5e41-4b59-93c2-575b7c6ea20d@n11g2000yqb.googlegroups.com>	<mailman.3973.1248969388.8015.python-list@python.org>	<0422bf8f-ce59-4de2-a1a4-b16a32e5f152@o15g2000yqm.googlegroups.com>
	<pan.2009.07.30.18.51.22.890000@nowhere.com>
Message-ID: <4A721097.50201@mrabarnett.plus.com>

Nobody wrote:
> On Thu, 30 Jul 2009 10:29:09 -0700, rurpy wrote:
> 
>>> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)')
>> You might also want to consider that some country
>> codes such as "co" for Columbia might match more than
>> you want, for example:
>>
>>   re.match(r'[\w\-\.]+\.(?:us|au|de|co)', 'foo.boo.com')
>>
>> will match.
> 
> ... so put \b at the end, i.e.:
> 
> regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)\b')
> 
It would still match "www.bbc.co.uk", so you might need:

regex = re.compile(r'[\w\-\.]+\.(?:us|au|de)\b(?!\.\b)')


From emmanuel.surleau at gmail.com  Thu Jul 30 17:29:21 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Thu, 30 Jul 2009 23:29:21 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
Message-ID: <200907302329.21286.emmanuel.surleau@gmail.com>

> 1.) No need to use "()" to call a function with no arguments.
> Python --> "obj.m2().m3()" --ugly
>   Ruby --> "obj.m1.m2.m3"  -- sweeet!
> Man, i must admit i really like this, and your code will look so much
> cleaner.

It has benefits - code does look better. It has also significant cons - it is 
ambiguous.
For instance:

a = b

Is b a variable or a method called without parameter?

> 2.) the .each method
> container.each{|localVar| block}
> This method can really cleanup some ugly for loops, although i really
> like the readability of for loops.

It's not only the 'each' method. It's "anonymous callbacks everywhere", which 
is pretty cool. Certainly one of my favourite features of Ruby.

> 3.) true OOP
> Now before you go and get all "huffy" over this statement, hear me
> out. Python is the best language in the world. But it damn sure has
> some warts! "len(this)" instead of "obj.length" max(that) instead of
> [1,2,3,4,5].max(). You know what i am talking about here people. We
> all get complacent and It seems easier to just cope with these
> problems instead of fighting for change.

While ob.length() is more clear to read, it follows the same "operator" logic 
as __iter__. Which is OK, I suppose.

> But look at the French,  WHAT
> THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!!

I assume this was supposed to be funny?

> As for the rest of Ruby, i am not impressed. The redundant usage of
> "end" over indention perplexes me.

You have the choice to use {}. If you are confused over languages which do not 
use indentation to delimit code blocks, you should probably try out a few 
languages outside Python.

> The Perlish feel of "require" and
> the horrifically cryptic idioms of Ruby regular expressions.

Cryptic idioms of Ruby regular expressions? They are Perl-like regular 
expressions, not exactly a far cry from what re does. Also, you can chain 
them, which is extremely nice.

> The "puts" and "gets" seem childish

Well, they're short and easy. Writing "gets" is more intuitive than using 
raw_input()

> and the math class does not even have
> a degrees or radians function!
>
> Anyway, i thought i would get this off my chest and catch up with old
> friends in the meantime. We can all make Python the perfect language
> it needs to be, but it ain't gonna be easy!
> Thank you all
>
> PS stay tuned for more from this series....

Cheers,

Emm


From python at mrabarnett.plus.com  Thu Jul 30 17:40:46 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 22:40:46 +0100
Subject: Regexp problem
In-Reply-To: <4A720AD5.1030202@stoneleaf.us>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>	<mailman.3961.1248959276.8015.python-list@python.org>	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>	<h4s7pm$rgr$1@adenine.netfront.net>
	<4A720AD5.1030202@stoneleaf.us>
Message-ID: <4A72135E.7060205@mrabarnett.plus.com>

Ethan Furman wrote:
> Marcus Wanner wrote:
>> On 7/30/2009 9:32 AM, Beldar wrote:
>>
>>> On 30 jul, 15:07, MRAB <pyt... at mrabarnett.plus.com> wrote:
>>>
>>>> Beldar wrote:
>>>>
>>>>> Hi there!
>>>>> I have a problem and i'm not very good at regular expressions.
>>>>> I have a text like "lalala lalala tiruri beldar-is-listening tiruri
>>>>> lalala" I need a regexp to get the 'beldar' part, the format is
>>>>> 'something-is-listening', i need to get the something part, use it in
>>>>> my code, and then replace the whole 'something-is-listening' for
>>>>> another string.
>>>>
>>>> \w+ will match a word and enclosing it in (...) will capture what was
>>>> matched:
>>>>
>>>>      m = re.search(r"(\w+)-is-listening", text)
>>>>      print "Captured '%s'" % m.group(1)
>>>>      print "Matched from %d to %d" % (m.start(), m.end())
>>>
>>>
>>> Ok, thank you all, it was very helpful!
>>
>> Wow, I really need to learn more about regexp...
>> Any tutorials you guys can recommend?
>>
>> Marcus
> 
> Mastering Regular Expressions
> Powerful Techniques for Perl and Other Tools
> By Jeffrey E. F. Friedl
> 
> Great book!
> 
+1

I have the first edition, seventh printing (December 1998). It refers to
the 'regex' module of Python 1.4b1, which was subsequently replaced by
the current 're' module and then removed from the standard library. I
hope it's been updated since then. :-)


From loic.domaigne at googlemail.com  Thu Jul 30 17:41:50 2009
From: loic.domaigne at googlemail.com (=?ISO-8859-1?Q?Lo=EFc_Domaign=E9?=)
Date: Thu, 30 Jul 2009 14:41:50 -0700 (PDT)
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
Message-ID: <3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>

Hi,

> Hello. I have written a Python 3.1 script running on Windows that uses
> os.path.exists() to connect to network shares. If the various network
> shares require different user account and password combos than the
> account the script is running under the routine returns false. I need
> something like os.samba.path.exists(username,password,path). Does
> anyone have a suggestion on how I can accomplish what I need to do in
> Python?

Could the Python Samba module PySamba be interesting for you?
http://sourceforge.net/projects/pysamba/

HTH,
Lo?c
--
My blog: http://www.domaigne.com/blog


From python at mrabarnett.plus.com  Thu Jul 30 17:44:31 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 22:44:31 +0100
Subject: New implementation of re module
In-Reply-To: <200907301524.28703.wolfgang@rohdewald.de>
References: <4A6DD6FB.8040609@mrabarnett.plus.com>	<4A719880.3070300@mrabarnett.plus.com>	<200907301518.28122.wolfgang@rohdewald.de>
	<200907301524.28703.wolfgang@rohdewald.de>
Message-ID: <4A72143F.6070506@mrabarnett.plus.com>

Wolfgang Rohdewald wrote:
> On Thursday 30 July 2009, Wolfgang Rohdewald wrote:
>> so I did the conversion mentioned there. This works:
> 
> I actually do not know if it works - but it compiles.
> 
Yes, it works. I've updated my code accordingly and it'll be in the next
release.


From rt8396 at gmail.com  Thu Jul 30 17:44:34 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 14:44:34 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
Message-ID: <23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>

On Jul 30, 4:29?pm, Emmanuel Surleau <emmanuel.surl... at gmail.com>
wrote:
> > 1.) No need to use "()" to call a function with no arguments.
> > Python --> "obj.m2().m3()" --ugly
> > ? Ruby --> "obj.m1.m2.m3" ?-- sweeet!
> > Man, i must admit i really like this, and your code will look so much
> > cleaner.
>
> It has benefits - code does look better. It has also significant cons - it is
> ambiguous.
> For instance:
>
> a = b
>
> Is b a variable or a method called without parameter?

Hello Emanuel,
Again, who so ever names a method with such a non-descriptive name
will get whats coming to him. And if you did for some reason use such
a cryptic name as "b", do yourself (and everyone else) a favor and
follow it with "()" to denote the method call. Remember when something
is optional that means you have an option to use it OR not use it.

optional (http://definr.com/optional)
  adj: possible but not necessary; left to personal choice [ant:
obligatory]


simple solutions for simple problems.


From zuo at chopin.edu.pl  Thu Jul 30 17:52:45 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Thu, 30 Jul 2009 23:52:45 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
Message-ID: <op.uxwhp7jufvx12t@jerzozwiesz.home.aster.pl>

Dnia 30-07-2009 o 22:41:57 Masklinn <masklinn at masklinn.net> napisa?(a):

> On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
>> 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
>>
>>> On 30 Jul 2009, at 06:04 , alex23 wrote:
>>>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>>>> 2.) the .each method
>>>>> container.each{|localVar| block}
>>>>> This method can really cleanup some ugly for loops, although i really
>>>>> like the readability of for loops.
>>>>
>>>> map(lambda localVar: <block>, sequence)
>>>>
>>>> or:
>>>>
>>>> def usefully_named_func(var):
>>>>   <block>
>>>>   return var
>>>>
>>>> transformed = [usefully_named_func(v) for v in sequence]
>>>>
>>> The issue here is of course that `map` and comprehensions are  
>>> transformations. `#each` exists for effectful iterations (Ruby has  
>>> `#map` for the map operation). So the intent expressed by `#each` and  
>>> `map` isn't the same. Furthermore and this is the most problematic  
>>> limitation of Python here, `lambda` doesn't allow complex  
>>> transformations due to its restrictions, so one has to switch to named  
>>> functions which works but isn't sexy (and tends to lower readability  
>>> imo).
>>
>> I don't see any real limitation. What's wrong in:
>>
>> for localVar in container:
>>    block
>>
> Well what's wrong with using that rather than `map`, `filter` or a list  
> comprehension? (and if you don't see what the limitations of `lambda`  
> are, you probably very rarely use it)

I know well about the expression-only-limitation of lambda, fortnately
there is the 'for' loop construct (or, alternatively, you can define
a named function).

And then, what's wrong with using 'for' rather than 'map', 'filter' etc.?
Agree, that 'anonymous block syntax' would be nice in some cases, but
I don't see any real limitation caused by lack of it i.e. something you
can't (all you can only with unreasonable effort).

>> And ruby's container.each is very similar to Python's iter()

> Uh? not at all?

OK, .each is like Python's iter() + some form of iterating over it
('for' loop or '[i]map'...).

Still, in this matter there is no real functionality in Ruby that you
can't reach in Python.

All that confessions of a (former?) Python fanboy are about sintactic
sugars, which importance is incomparable which such issues as e.g.
particular mechanism of classes, their inheritance etc. or even such
small helpers like function annotations.

Cheers,

*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From kyrie at uh.cu  Thu Jul 30 17:57:48 2009
From: kyrie at uh.cu (Luis Zarrabeitia)
Date: Thu, 30 Jul 2009 17:57:48 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
Message-ID: <200907301757.48761.kyrie@uh.cu>

On Thursday 30 July 2009 04:41:57 pm Masklinn wrote:
> On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
> > 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
> >
> > I don't see any real limitation. What's wrong in:
> >
> > for localVar in container:
> >    block
>
> Well what's wrong with using that rather than `map`, `filter` or a
> list comprehension?

As I understood the question, it was "was wrong in 'for var in container' in 
comparison with ruby's container.each?"

What's the (semantic) difference between

for localVar in container:
    block

and

container.each{|localVar| block}

?

(the sintactic difference is quite clear... if there is no semantic 
difference, I'd rather use the first version!)

Map, filter and comprehensions have little to do with that (syntactic sugar 
that may allow some optimizations, but that could otherwise be replaced by 
the for loop).

> (and if you don't see what the limitations of 
> `lambda` are, you probably very rarely use it)

I'm not the poster, but: 
* I use lambdas, a lot.
* I "know" python lambdas are limited, compared with theoretical lambdas.
* I don't [usually] see that as a "limitation".

Most of the time, the limitation is the lack of multiline/multiexpression 
lambdas. But I've never seen a case where I would /prefer/ to have a 
multiline function definition inside a comprehension or method invocation, 
instead of a named function defined two lines before it.

(The second famous limitation is the inability to use statements inside 
lambdas... luckily, now that we have a ternary operator and a print function, 
it is less limiting)

> > And ruby's container.each is very similar to Python's iter()
>
> Uh? not at all?

I agree with this. It should have said that they are equivalent in the sense 
that they represent the iterator protocols of both languages, and nothing 
more.

I'd like to ask, what "container.each" is, exactly? It looks like a function 
call (as I've learned a few posts ago), but, what are its arguments? How the 
looping "works"? Does it receive a "code" object that it has to execute? 
Is .each some kind of magic keyword? (This has little to do with python or 
the current thread, so feel free to reply off-list if you want to...)

Regards,

Luis.

-- 
Luis Zarrabeitia (aka Kyrie)
Fac. de Matem?tica y Computaci?n, UH.
http://profesores.matcom.uh.cu/~kyrie


From python at mrabarnett.plus.com  Thu Jul 30 18:06:05 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Thu, 30 Jul 2009 23:06:05 +0100
Subject: New implementation of re module
In-Reply-To: <m21vnye1d4.fsf@cs.uu.nl>
References: <mailman.3787.1248712420.8015.python-list@python.org>
	<m21vnye1d4.fsf@cs.uu.nl>
Message-ID: <4A72194D.4050604@mrabarnett.plus.com>

Piet van Oostrum wrote:
>>>>>> MRAB <python at mrabarnett.plus.com> (M) wrote:
> 
>> M> Hi all,
>> M> I've been working on a new implementation of the re module. The details
>> M> are at http://bugs.python.org/issue2636, specifically from
>> M> http://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
>> M> Python 2.6 on Windows if you want to try it out.
> 
>> M> I'm interested in how fast it is generally, compared with the current re
>> M> module, but especially when faced with those 'pathological' regular
>> M> expressions which seem to take a long time to finish, for example:
> 
>> M>     re.search(r"^(.+|D)*A$", "x" * 25 + "B")
> 
>> M> which on my PC (1.8GHz) takes 18.98secs with the re module but <0.01secs
>> M> with this new implementation.
> 
> Is this version also going to use the Thompson approach?

That approach is what inspired the method in the new implementation, but
its speed comes from asking _whether_ there's a match, not _where_
there's a match, so it can ignore the route taken to get the match.

"grep", for example, selects those lines which match a pattern, whereas
the typical Python (and Perl) usage is to extract part of a string or
which part of the string matches.

Trying to support lazy and possessive quantifiers in Thompson's approach
is tricky (at least, I haven't been able to figure it out), and
back-references are right out! :-)

There's always the chance that I could come up with some sort of hybrid
scheme, applying different approaches depending on certain conditions.
It already switches from depth-first to breadth-first when it's taken
too many iterations without advancing and merges similar states, which
is why it's so much better with 'pathological' patterns; I just have to
get the depth-first phase to be as fast as the current 're' module.


From benjamin.kaplan at case.edu  Thu Jul 30 18:08:21 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Thu, 30 Jul 2009 18:08:21 -0400
Subject: calling obect method
In-Reply-To: <960855.56660.qm@web7906.mail.in.yahoo.com>
References: <960855.56660.qm@web7906.mail.in.yahoo.com>
Message-ID: <ec96e1390907301508m4b98a60bm3af3b2bee234e79e@mail.gmail.com>

On Thu, Jul 30, 2009 at 3:04 PM, srinivasan srinivas <
sri_annauni at yahoo.co.in> wrote:

> Hi,
> I would like to know if i have an object and one of its methods as a
> string. How to call the method using this string?
> For ex
> If object is x and string y has one of its method names.
> x.value(y)() ---. Is there a way to do this?
>
> Thanks,
> Srini



getattr(x,y)()

>
>
>
>      See the Web's breaking stories, chosen by people like you. Check out
> Yahoo! Buzz. http://in.buzz.yahoo.com/
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/fa5a0b18/attachment-0001.html>

From rt8396 at gmail.com  Thu Jul 30 18:13:41 2009
From: rt8396 at gmail.com (r)
Date: Thu, 30 Jul 2009 15:13:41 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net> 
	<mailman.4003.1248991082.8015.python-list@python.org>
Message-ID: <80839e72-9df4-4590-b22d-4c5c829e37b6@h11g2000yqb.googlegroups.com>

On Jul 30, 4:57?pm, Luis Zarrabeitia <ky... at uh.cu> wrote:
[snip]
> I'd like to ask, what "container.each" is, exactly? It looks like a function
> call (as I've learned a few posts ago), but, what are its arguments? How the
> looping "works"? Does it receive a "code" object that it has to execute?
> Is .each some kind of magic keyword? (This has little to do with python or
> the current thread, so feel free to reply off-list if you want to...)
>
> Regards,
>
> Luis.

Hello Luis,

I think your question is completely valid within the context of this
thread. The purpose of his thread was to get feedback on how Python
and Ruby ideas could be cumulated into the best high level language.
And being that i am the BDFL of the "Confessions of a Python Fanboy"
thread, you have my personal permission to continue on with this
subject matter...,



From rcdailey at gmail.com  Thu Jul 30 18:40:37 2009
From: rcdailey at gmail.com (Robert Dailey)
Date: Thu, 30 Jul 2009 15:40:37 -0700 (PDT)
Subject: Printing with colors in a portable way
Message-ID: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>

Anyone know of a way to print text in Python 3.1 with colors in a
portable way? In other words, I should be able to do something like
this:

print_color( "This is my text", COLOR_BLUE )

And this should be portable (i.e. it should work on Linux, Mac,
Windows).


From nyamatongwe+thunder at gmail.com  Thu Jul 30 18:47:35 2009
From: nyamatongwe+thunder at gmail.com (Neil Hodgson)
Date: Thu, 30 Jul 2009 22:47:35 GMT
Subject: No PyPI search for 3.x compatible packages
In-Reply-To: <d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
References: <Wj5cm.8143$ze1.4079@news-server.bigpond.net.au>
	<d31fc21f-8526-4d07-a128-b256a9ea14aa@o15g2000yqm.googlegroups.com>
Message-ID: <bqpcm.8332$ze1.7277@news-server.bigpond.net.au>

Francesco Bochicchio :

> Are you sure? I note that for example pygtk has as language tags both
> C and python. So maybe a C extension
> for python3 would have both C and python 3 as language tags.
> 
> I suspect that the 109 packages you found are the only ones obf the
> 4829 which works with python3 (but I hope
> to be wrong ).

   There are 523 packages marked with Python :: [2, 2.1, ...] and I hope
more than that work with Python 2.x.

   What I would like to encourages is adding Python :: 3 or a more
specific minimum supported version classifier to packages that support
Python 3. I wouldn't want to go to the level of adding a classifier for
each version of Python supported since a package will often stay valid
when a new Python is released.

   Neil


From gdamjan at gmail.com  Thu Jul 30 18:59:31 2009
From: gdamjan at gmail.com (=?UTF-8?B?0JTQsNC80ZjQsNC9INCT0LXQvtGA0LPQuNC10LLRgdC60Lg=?=)
Date: Fri, 31 Jul 2009 00:59:31 +0200
Subject: [ANN] pyKook 0.0.2 - a simple build tool similar to Make or Ant
References: <c0c0453c-c4ca-47a3-bf76-d2b7e2fad7ff@b25g2000prb.googlegroups.com>
Message-ID: <l7l9k6-st.ln1@archaeopteryx.softver.org.mk>

> I have released pyKook 0.0.2.
> http://pypi.python.org/pypi/Kook/0.0.2
> http://www.kuwata-lab.com/kook/
> http://www.kuwata-lab.com/kook/pykook-users-guide.html

How does it compare to http://code.google.com/p/fabricate/

and why is this problem (solution) reoccurring all the time


-- 
?????? ( http://softver.org.mk/damjan/ )

Teaching a pig to sing wastes your time & annoys the pig.



From robert.kern at gmail.com  Thu Jul 30 19:06:31 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Thu, 30 Jul 2009 18:06:31 -0500
Subject: Confessions of a Python fanboy
In-Reply-To: <23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
Message-ID: <h4t91n$obg$1@ger.gmane.org>

On 2009-07-30 16:44, r wrote:
> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com>
> wrote:
>>> 1.) No need to use "()" to call a function with no arguments.
>>> Python -->  "obj.m2().m3()" --ugly
>>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
>>> Man, i must admit i really like this, and your code will look so much
>>> cleaner.
>> It has benefits - code does look better. It has also significant cons - it is
>> ambiguous.
>> For instance:
>>
>> a = b
>>
>> Is b a variable or a method called without parameter?
>
> Hello Emanuel,
> Again, who so ever names a method with such a non-descriptive name
> will get whats coming to him. And if you did for some reason use such
> a cryptic name as "b", do yourself (and everyone else) a favor and
> follow it with "()" to denote the method call. Remember when something
> is optional that means you have an option to use it OR not use it.

I believe his point is that it is ambiguous to the compiler, not humans reading 
the code. Python functions and methods are first class objects. They can be 
passed around. If they were auto-called, then you could not do this.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From rhodri at wildebst.demon.co.uk  Thu Jul 30 19:29:50 2009
From: rhodri at wildebst.demon.co.uk (Rhodri James)
Date: Fri, 31 Jul 2009 00:29:50 +0100
Subject: Printing with colors in a portable way
In-Reply-To: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
Message-ID: <op.uxwl70c1a8ncjz@gnudebst>

On Thu, 30 Jul 2009 23:40:37 +0100, Robert Dailey <rcdailey at gmail.com>  
wrote:

> Anyone know of a way to print text in Python 3.1 with colors in a
> portable way? In other words, I should be able to do something like
> this:
>
> print_color( "This is my text", COLOR_BLUE )
>
> And this should be portable (i.e. it should work on Linux, Mac,
> Windows).

...in an xterm, over a telnet connection, via VNC...

There's no portable way of doing this in any language, since it's
up to the terminal emulator exactly what it does with what incoming
bytes.  Some respect the ANSI colour codes, some don't; that's about
all that you can say.

-- 
Rhodri James *-* Wildebeest Herder to the Masses


From zuo at chopin.edu.pl  Thu Jul 30 19:54:20 2009
From: zuo at chopin.edu.pl (Jan Kaliszewski)
Date: Fri, 31 Jul 2009 01:54:20 +0200
Subject: Printing with colors in a portable way
In-Reply-To: <op.uxwl70c1a8ncjz@gnudebst>
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
	<op.uxwl70c1a8ncjz@gnudebst>
Message-ID: <op.uxwncuztfvx12t@jerzozwiesz.home.aster.pl>

31-07-2009 o 01:29:50 Rhodri James <rhodri at wildebst.demon.co.uk> wrote:

> On Thu, 30 Jul 2009 23:40:37 +0100, Robert Dailey <rcdailey at gmail.com>  
> wrote:
>
>> Anyone know of a way to print text in Python 3.1 with colors in a
>> portable way? In other words, I should be able to do something like
>> this:
>>
>> print_color( "This is my text", COLOR_BLUE )
>>
>> And this should be portable (i.e. it should work on Linux, Mac,
>> Windows).
>
> ...in an xterm, over a telnet connection, via VNC...
>
> There's no portable way of doing this in any language, since it's
> up to the terminal emulator exactly what it does with what incoming
> bytes.  Some respect the ANSI colour codes, some don't; that's about
> all that you can say.

Yeah. Although you could try to provide "term-sensitive" mapping
of colour names -> codes, e.g.:

# color_codes.py

class NoColors:
     blue = ''
     red = ''

class XtermColors:
     blue = '<a code here>'
     red = '<a code here>'

class FooBarColors:
     blue = '<a code here>'
     red = '<a code here>'

COLORS = {
     'nocolors': NoColors,
     'xterm': XtermColors,
     'another term': FooBarColors,
}


# a_program.py

import color_codes

# e.g. with used_term == 'xterm'...
colors = color_codes.COLORS[used_term]

print('Some text, {colors.blue}Something in blue, '
       '{colors.red}And now in red.').format(colors=colors)


Regards,
*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>


From gagsl-py2 at yahoo.com.ar  Thu Jul 30 20:04:01 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Thu, 30 Jul 2009 21:04:01 -0300
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com>
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com>
	<4A7199FF.8010202@dejaviewphoto.com>
	<mailman.3970.1248966648.8015.python-list@python.org>
	<27mdnb-NxM3DJOzXnZ2dnUVZ_hxi4p2d@posted.visi>
Message-ID: <op.uxwnszkpx6zn5v@lepton.softlabbsas.com.ar>

En Thu, 30 Jul 2009 12:16:46 -0300, Unknown <unknown at unknown.invalid>  
escribi?:
> On 2009-07-30, Barak, Ron <Ron.Barak at lsi.com> wrote:

>> On second thoughts, I may have a problem implementing the
>> wrapper solution, because my actual test_pyc.pyc, needs to
>> parse its command line. Namely, the actual call to
>> test_pyc.pyc looks something like this:
>>
>> $ python  test_pyc.py -U dave -PpasswoRD -C CreateMcGroupOnVolume  
>> --SVMs_IPs '10.1.1.1 , 10.1.1.2' -n "host1,host2" -g gn -j jn -s svn -t  
>> tvn -p pool1 -l -c
>>
>> And I don't know of a way to add these parameters to the
>> "import test_pyc" in wrapper
>>
>> Is there a way to pass information to an imported module ?
>> (Sorry if there's an obvious answer, I just cannot figure it
>> out).
>
> I don't understand your problem.  The module would parse
> sys.argv just like always.
>
> If you don't like that for some reason, you could define an
> entry point in the module and call it:
>
> #!/usr/bin/python
> import sys,test_pyc
> test_pyc.main(*sys.argv)

And you *should* do it that way, instead of just importing the other  
module and executing ALL the program as a side-effect of the import  
statement. In the first case, the import lock will prevent other threads  
to run.

-- 
Gabriel Genellina



From digitig at gmail.com  Thu Jul 30 20:05:29 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 31 Jul 2009 01:05:29 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <4a71e1a5$0$40016$4fafbaef@reader3.news.tin.it>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<4a71e1a5$0$40016$4fafbaef@reader3.news.tin.it>
Message-ID: <aee48b3c0907301705p3b34e561rb77752297eec7125@mail.gmail.com>

2009/7/30 superpollo <user at example.net>:
> Tim Rowe wrote:

>> Any language that gets any sort of real use has to have. For instance,
>> I love Ada's numeric types (you can specify either the minimum number
>> of significant figures or the maximum delta for a real type, and it
>> will give you a type that satisfies that -- or a compilation error if
>> it can't. ?That matches genuine problem domains far better
>
> doesn't the decimal module do some of that too?

Not as far as I can tell, no.

-- 
Tim Rowe


From j.sundo at cs.ucl.ac.uk  Thu Jul 30 20:17:04 2009
From: j.sundo at cs.ucl.ac.uk (=?ISO-8859-1?Q?Jannik_Sund=F8?=)
Date: Fri, 31 Jul 2009 01:17:04 +0100
Subject: Confused About Python Loggin
Message-ID: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>

Dear all, I am quite confused about the Python logging. I have read  
and re-read the Python documentation for the Python logging module and  
googled, but to no avail. I simply want one logger to log to a file  
and another logger to log to the console. Neither should log the  
other's messages. The code below causes fileLogger to log to BOTH a  
file and the console, how come? It seems to me that a call such as  
"consoleHandler = logging.StreamHandler()" affects other loggers,  
which I do not want. Also, if I do not do  
logging.basicConfig(level=logging.INFO) in one of the classes of my  
application, the logging does not work. Any ideas how come?

Thanks a lot for any help! :)

fileHandler = logging.FileHandler('../../logs/log.txt')
fileLogger = logging.getLogger('TESTHARNESSFILE')
fileLogger.addHandler(fileHandler)
fileLogger.setLevel(logging.INFO)
consoleHandler = logging.StreamHandler()
logger = logging.getLogger('TESTHARNESS')
logger.addHandler(consoleHandler)
logger.setLevel(logging.INFO)


From dhaneshpai at gmail.com  Thu Jul 30 20:24:10 2009
From: dhaneshpai at gmail.com (Dhanesh)
Date: Thu, 30 Jul 2009 17:24:10 -0700 (PDT)
Subject: Non-blocking read with popen subprocess
Message-ID: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>

Hi ,

I am trying to use subprocess popen on a windows command line
executable with spits messages on STDOUT as well as STDIN. Code
snippet is as below :-
##########################################################################
sOut=""
    sErr=""
    javaLoaderPath = os.path.join("c:\\","Program Files","Research In
Motion","BlackBerry JDE 4.7.0","bin","Javaloader.exe")
    cmd = [javaLoaderPath,'-u','load','helloworld.jad']
    popen = subprocess.Popen
(cmd,bufsize=256,shell=False,stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
    while True:
        sErr = sErr + popen.stderr.read(64)
        sOut = sOut + popen.stdout.read(64)------------------> Blocks
here
        if None != popen.poll():
            break;
##########################################################################

I observed that python scripts blocks at stdout read on the other hand
when I do not create a child stdout PIPE  say  " stdout=None" , things
seems to be working fine.

how can I we have a non blocking read ?
And why does stdout block even where data is available to be read
( which seem to be apparent when stdout=None, and logs appear on
parents STDOUT) ?



From tjreedy at udel.edu  Thu Jul 30 20:38:15 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Thu, 30 Jul 2009 20:38:15 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <39013d06-e281-4459-bdb2-19831c9526ea@k1g2000yqf.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<196929f0-9b3f-4210-aa34-d7ab64bc934d@n11g2000yqb.googlegroups.com>
	<mailman.3976.1248974120.8015.python-list@python.org>	<19f8b41f-27ec-4563-90db-8a984d1f88e5@26g2000yqk.googlegroups.com>	<4a71e102$0$40016$4fafbaef@reader3.news.tin.it>	<mailman.3995.1248987328.8015.python-list@python.org>
	<39013d06-e281-4459-bdb2-19831c9526ea@k1g2000yqf.googlegroups.com>
Message-ID: <h4tedl$4c4$1@ger.gmane.org>

r wrote:
> On Jul 30, 3:55 pm, Terry Reedy <tjre... at udel.edu> wrote:
>> superpollo wrote:
>>> r wrote:
>>> how to reverse a string in python? must i usa a temp? like:
> [snip]
>> Terry Jan Reedy
> 
> No "r" never wrote anything like that. reversing a string is RTFM
> material, this is basic stuff here! Stop quoting me as saying things i
> did not say! I never asked how to reverse a string, "superpollo"
> did.

Nor did what I posted say that you did. The above says that superpollo 
wrote "how to reverse..., as he did. Quotes are indented once more than 
the author. The above says 'r wrote' with no indent and then "No...", 
which you did write, indented once.

I agree that since I did not quote anything that you wrote, I should 
also have snipped your name. But I least I do attempt to snip material 
irrelavant to my comments.

Terry Jan Reedy



From brochu121 at gmail.com  Thu Jul 30 20:57:56 2009
From: brochu121 at gmail.com (David Brochu)
Date: Thu, 30 Jul 2009 20:57:56 -0400
Subject: httplib headers
Message-ID: <9583ed900907301757q50e85b42o830820980386ff57@mail.gmail.com>

Using the following code I am trying to pass a header to my POST request.
(Note: urls masked)

file = sys.argv[0]
url = sys.argv[1]
conn = httplib.HTTPConnection("XX.XXX.XX.XXX",XXXX)
headers = {'content-type':'application/xml'}
conn.request("POST",url,file,headers)
response = conn.getresponse()
head = response.getheaders()
status = response.status
response = response.read()
print response, status, head

When I run this script and view the headers that get printed the following
displays:

[('content-length', '691'), ('proxy-connection', 'Keep-Alive'),
('connection', 'Keep-Alive'), ('pragma', 'no-cache'), ('cache-control',
'no-cache'), ('content-type', 'text/html; charset=utf-8')]
Why isn't my content-type header using the value I pass in from headers?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090730/99e547a7/attachment-0001.html>

From aahz at pythoncraft.com  Thu Jul 30 21:13:53 2009
From: aahz at pythoncraft.com (Aahz)
Date: 30 Jul 2009 18:13:53 -0700
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org>
	<157EBE1D-3ACF-4A3D-BDCD-F094695D0707@rgbaz.eu>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26CA@enbmail01.lsi.com>
	<mailman.3949.1248951463.8015.python-list@python.org>
Message-ID: <h4tggh$6rt$1@panix3.panix.com>

In article <mailman.3949.1248951463.8015.python-list at python.org>,
Chris Rebert  <clp2 at rebertia.com> wrote:
>
>No, with the shebang line (and assuming execute permissions on the
>file), it would look like:
>
>./wrapper.py

There's no reason to name it ".py"; you can have a perfectly useful
"shell script" that just happens to list python on the shebang line
instead of the usual /bin/sh.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From python at mrabarnett.plus.com  Thu Jul 30 21:20:40 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 02:20:40 +0100
Subject: httplib headers
In-Reply-To: <9583ed900907301757q50e85b42o830820980386ff57@mail.gmail.com>
References: <9583ed900907301757q50e85b42o830820980386ff57@mail.gmail.com>
Message-ID: <4A7246E8.3010400@mrabarnett.plus.com>

David Brochu wrote:
> Using the following code I am trying to pass a header to my POST 
> request. (Note: urls masked)
>  
> file = sys.argv[0]
> url = sys.argv[1]
> conn = httplib.HTTPConnection("XX.XXX.XX.XXX",XXXX)
> headers = {'content-type':'application/xml'}
> conn.request("POST",url,file,headers)
> response = conn.getresponse()
> head = response.getheaders()
> status = response.status
> response = response.read()
> print response, status, head
>  
> When I run this script and view the headers that get printed the 
> following displays:
>  
> [('content-length', '691'), ('proxy-connection', 'Keep-Alive'), 
> ('connection', 'Keep-Alive'), ('pragma', 'no-cache'), ('cache-control', 
> 'no-cache'), ('content-type', 'text/html; charset=utf-8')]
> Why isn't my content-type header using the value I pass in from headers?
> 
Aren't you just setting the headers for the "POST" you're sending
(you're posting a file whose content type is 'application/xml'), but
printing the headers of the response you receive (the content type of
the response is 'text/html; charset=utf-8')?


From jgardner at jonathangardner.net  Thu Jul 30 22:30:46 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Thu, 30 Jul 2009 19:30:46 -0700 (PDT)
Subject: Non-blocking read with popen subprocess
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
Message-ID: <824f8092-55b1-4df2-a6b5-74a4b1b1d9ea@i18g2000pro.googlegroups.com>

On Jul 30, 5:24?pm, Dhanesh <dhanesh... at gmail.com> wrote:
>
> how can I we have a non blocking read ?

See http://docs.python.org/library/popen2.html#flow-control-issues

Note well: In the non-blocking world, you have to use select() or poll
() to get your job done.

You may want to look at "communicate" (http://docs.python.org/library/
subprocess.html#popen-objects) which may be what you need.


From lukepadawan at gmail.com  Thu Jul 30 22:55:40 2009
From: lukepadawan at gmail.com (Lucas P Melo)
Date: Thu, 30 Jul 2009 23:55:40 -0300
Subject: Generators through the C API
Message-ID: <4A725D2C.4030705@gmail.com>

Hello, I'm a total noob about the C API. Is there any way to create a 
generator function using the C API? I couldn't find anything like the 
'yield' keyword in it.

Thanks in advance.


From grante at visi.com  Thu Jul 30 23:02:17 2009
From: grante at visi.com (Grant Edwards)
Date: Thu, 30 Jul 2009 22:02:17 -0500
Subject: Printing with colors in a portable way
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
Message-ID: <cfydnSlcPuYkw-_XnZ2dnUVZ_rCdnZ2d@posted.usinternet>

On 2009-07-30, Robert Dailey <rcdailey at gmail.com> wrote:
> Anyone know of a way to print text in Python 3.1 with colors in a
> portable way? In other words, I should be able to do something like
> this:
>
> print_color( "This is my text", COLOR_BLUE )
>
> And this should be portable (i.e. it should work on Linux, Mac,
> Windows).

Generating postscript or PDF is the only remotely portable way
to print anything.

-- 
Grant



From cocobear.cn at gmail.com  Fri Jul 31 00:18:25 2009
From: cocobear.cn at gmail.com (cocobear)
Date: Thu, 30 Jul 2009 21:18:25 -0700 (PDT)
Subject: merge two png pic
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
Message-ID: <b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>

On Jul 29, 9:20?am, cocobear <cocobear... at gmail.com> wrote:
> Thistwopngfile has their own palette
>
> >>> im1.mode
> 'P'
> >>> im.mode
> 'P'
> >>> im.getpalette == im1.getpalette
>
> False
>
> I can use this code tomergetwopngpictogether:
>
> Map = Image.new("RGB", (x,y))
> Map.paste(im, box)
> Map.paste(im1,box)
>
> Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)
>
> But if thetwopngpicis too big , or if I have tomergemorepic
> together, I will get MemoryError:
>
> >>> Image.new("RGB",(44544,38656))
>
> Traceback (most recent call last):
> ? File "<stdin>", line 1, in <module>
> ? File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
> new
> ? ? return Image()._new(core.fill(mode, size, color))
> MemoryError
>
> How can I directlymergetwopicto a ?P' modepngwith palette.


Nobody replied.


From ivlenin at gmail.com  Fri Jul 31 01:27:22 2009
From: ivlenin at gmail.com (I V)
Date: 31 Jul 2009 07:27:22 +0200
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<mailman.4003.1248991082.8015.python-list@python.org>
Message-ID: <4a7280ba$1@news.x-privat.org>

On Thu, 30 Jul 2009 17:57:48 -0400, Luis Zarrabeitia wrote:
> As I understood the question, it was "was wrong in 'for var in
> container' in comparison with ruby's container.each?"
> 
> What's the (semantic) difference between
> 
> for localVar in container:
>     block
> 
> and
> 
> container.each{|localVar| block}

I don't think "each" is a particularly compelling example of Ruby's 
blocks - as you say, it's easily replaceable with a Python for-loop. The 
advantage of Ruby's syntax is that it allows you to define further 
functions that are sort-of like new control structures. So you have 
things like:

File.open('myfile', 'r') do |file|
	while line = file.gets
		puts line
	end
end

Which is like a python's:

with open('myfile', 'r) as f:
	for line in f:
		print f

However, with Ruby, this kind of scoping construct can be added without 
adding new syntax. Another interesting example is the Sinatra web 
framework, which allows you to write a web app with something like:

get '/' do
	"Index page"
end

post '/:name' do 
	"Posted to " + params[:name]
end

Which looks something like a DSL for web apps, but is accomplished solely 
with normal ruby functions. More: http://www.sinatrarb.com/intro.html

Ruby blocks are, fundamentally, syntactic sugar, but they are kind of 
neat.


From emmanuel.surleau at gmail.com  Fri Jul 31 01:46:49 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 07:46:49 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <h4t91n$obg$1@ger.gmane.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<h4t91n$obg$1@ger.gmane.org>
Message-ID: <200907310746.49392.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 01:06:31 Robert Kern wrote:
> On 2009-07-30 16:44, r wrote:
> > On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com>
> >
> > wrote:
> >>> 1.) No need to use "()" to call a function with no arguments.
> >>> Python -->  "obj.m2().m3()" --ugly
> >>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
> >>> Man, i must admit i really like this, and your code will look so much
> >>> cleaner.
> >>
> >> It has benefits - code does look better. It has also significant cons -
> >> it is ambiguous.
> >> For instance:
> >>
> >> a = b
> >>
> >> Is b a variable or a method called without parameter?
> >
> > Hello Emanuel,
> > Again, who so ever names a method with such a non-descriptive name
> > will get whats coming to him. And if you did for some reason use such
> > a cryptic name as "b", do yourself (and everyone else) a favor and
> > follow it with "()" to denote the method call. Remember when something
> > is optional that means you have an option to use it OR not use it.
>
> I believe his point is that it is ambiguous to the compiler, not humans
> reading the code.

Actually, both. Use a variable you didn't initialize? This is what you get:

NameError: undefined local variable or method `b' for main:Object
        from (irb):1

The compiler has no idea if b is a variable or a method. It also makes it very 
easy to shadow an existing method by declaring a variable of the same name, 
which is problematic. I suppose it is a side-effect of Ruby's Perl 
philosophical inheritance - except that Perl uses sigils to prefix its 
variables, negating this issue.

Cheers,

Emm


From steve at nospam.au  Fri Jul 31 02:09:48 2009
From: steve at nospam.au (steve)
Date: Fri, 31 Jul 2009 16:09:48 +1000
Subject: Test for Pythonwin?
Message-ID: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>

Is there a good way to check if a script is running inside Pythonwin?
Perhaps a property or method that is exposed by that environment?

or, alternatively, is there a better place to ask :-)

Steven 




From __peter__ at web.de  Fri Jul 31 02:52:01 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 08:52:01 +0200
Subject: merge two png pic
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
	<b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>
Message-ID: <h4u4al$qtm$02$1@news.t-online.com>

cocobear wrote:

> On Jul 29, 9:20 am, cocobear <cocobear... at gmail.com> wrote:
>> Thistwopngfile has their own palette
>>
>> >>> im1.mode
>> 'P'
>> >>> im.mode
>> 'P'
>> >>> im.getpalette == im1.getpalette
>>
>> False
>>
>> I can use this code tomergetwopngpictogether:
>>
>> Map = Image.new("RGB", (x,y))
>> Map.paste(im, box)
>> Map.paste(im1,box)
>>
>> Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)
>>
>> But if thetwopngpicis too big , or if I have tomergemorepic
>> together, I will get MemoryError:
>>
>> >>> Image.new("RGB",(44544,38656))

As a workaround you could split the image into tiles that fit into your 
machine's RAM. Or you could try to do the rendering on a 64-bit system. 
You'll need at least

>>> 3*44544*38656./(2**30)
4.8109130859375

5 gigabytes for the target image plus memory for the biggest source image. 
Alternatively there are probably tools that can keep parts of the image on 
disk (imagemagick, maybe? you'll have to check yourself or ask in a 
specialized forum). As a last resort you should be able to write such a tool 
yourself. I don't know how hard it would be to generate the PNG, but the RGB 
pasting should be trivial.

>> Traceback (most recent call last):
>> File "<stdin>", line 1, in <module>
>> File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
>> new
>> return Image()._new(core.fill(mode, size, color))
>> MemoryError
>>
>> How can I directlymergetwopicto a ?P' modepngwith palette.
> 
> 
> Nobody replied.

What do you want to do with such a big image? You will run into the same 
limitation when you are trying to display it.

Peter



From tjreedy at udel.edu  Fri Jul 31 02:52:56 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 02:52:56 -0400
Subject: merge two png pic
In-Reply-To: <b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>
References: <d80ce49e-0ccc-45d0-bb5e-504a94c3625c@12g2000pri.googlegroups.com>
	<b7df28f6-b00a-4691-bb55-a653bf8e3cec@f18g2000prf.googlegroups.com>
Message-ID: <h4u4c5$dsp$1@ger.gmane.org>

cocobear wrote:
> On Jul 29, 9:20 am, cocobear <cocobear... at gmail.com> wrote:
>> Thistwopngfile has their own palette
>>
>>>>> im1.mode
>> 'P'
>>>>> im.mode
>> 'P'
>>>>> im.getpalette == im1.getpalette
>> False
>>
>> I can use this code tomergetwopngpictogether:
>>
>> Map = Image.new("RGB", (x,y))
>> Map.paste(im, box)
>> Map.paste(im1,box)
>>
>> Map = Map.convert("L", optimize=True, palette=Image.ADAPTIVE)
>>
>> But if thetwopngpicis too big , or if I have tomergemorepic
>> together, I will get MemoryError:
>>
>>>>> Image.new("RGB",(44544,38656))
>> Traceback (most recent call last):
>>   File "<stdin>", line 1, in <module>
>>   File "/usr/lib/python2.5/site-packages/PIL/Image.py", line 1710, in
>> new
>>     return Image()._new(core.fill(mode, size, color))
>> MemoryError
>>
>> How can I directlymergetwopicto a ?P' modepngwith palette.
> 
> 
> Nobody replied.

A. Leavingoutspacesmakesyourposthardtoread.

B. Nobody knows how to avoid mem error.

tjr




From shearichard at gmail.com  Fri Jul 31 03:09:48 2009
From: shearichard at gmail.com (northof40)
Date: Fri, 31 Jul 2009 00:09:48 -0700 (PDT)
Subject: Python 2.6 in shared/VPS environment
Message-ID: <6babf860-0161-4c1a-82f8-69e03dc53da0@p36g2000prn.googlegroups.com>

Hi - I'd really like to have access to Python 2.6 to try something
out. It needs to be on Linux/Unix machine. I don't mind paying but
whichever way I turn I find Python 2.4 is the standard installation.

Anyone know of anyone who offers this out of the box ? Or got any
smart way of achieving it ?

thanks

R.





From __peter__ at web.de  Fri Jul 31 03:14:59 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 09:14:59 +0200
Subject: Confused About Python Loggin
References: <mailman.4011.1249000497.8015.python-list@python.org>
Message-ID: <h4u5lf$24c$01$1@news.t-online.com>

Jannik Sund? wrote:

> Dear all, I am quite confused about the Python logging. I have read
> and re-read the Python documentation for the Python logging module and
> googled, but to no avail. I simply want one logger to log to a file
> and another logger to log to the console. Neither should log the
> other's messages. The code below causes fileLogger to log to BOTH a
> file and the console, how come? It seems to me that a call such as
> "consoleHandler = logging.StreamHandler()" affects other loggers,
> which I do not want. Also, if I do not do
> logging.basicConfig(level=logging.INFO) in one of the classes of my
> application, the logging does not work. Any ideas how come?
> 
> Thanks a lot for any help! :)
> 
> fileHandler = logging.FileHandler('../../logs/log.txt')
> fileLogger = logging.getLogger('TESTHARNESSFILE')
> fileLogger.addHandler(fileHandler)
> fileLogger.setLevel(logging.INFO)
> consoleHandler = logging.StreamHandler()
> logger = logging.getLogger('TESTHARNESS')
> logger.addHandler(consoleHandler)
> logger.setLevel(logging.INFO)

The code you present should work as you expect:

$ cat tmp.py
import logging

fileHandler = logging.FileHandler('tmp.txt')
fileLogger = logging.getLogger('TESTHARNESSFILE')
fileLogger.addHandler(fileHandler)
fileLogger.setLevel(logging.INFO)

consoleHandler = logging.StreamHandler()
logger = logging.getLogger('TESTHARNESS')
logger.addHandler(consoleHandler)
logger.setLevel(logging.INFO)


logger.info("to console")
fileLogger.info("to file")
$ python tmp.py
to console
$ cat tmp.txt
to file

What problems exactly are you running into if you omit the basicConfig() 
call?

Peter



From malc0de.encrypt at gmail.com  Fri Jul 31 03:25:09 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 00:25:09 -0700 (PDT)
Subject: problem on socket programming
Message-ID: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>

hello there, I'm using Learning Python 3rd edition as my core
reference, the book is great.
here's some snippet for demonstrating echo-server program, but I can't
interpret it in both windows / Gnu linux ...

#!/usr/bin/env python
from socket import *
myHost = ''
myPort = 50007
sockobj = socket(AF_INET,SOCK_STREAM)
sockobj.bind((myHost,myPort))
sockobj.listen(5)
while true :
    connection,address = sockobj.accept()
    print 'server connected by :',address
    while True:
        data = connection.recv(1024)
        if not data: break
        connection.send('echo : '+ data)
    connection.close()

where's the problem,
beforehand appreciate ...


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 03:28:29 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 07:28:29 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<mailman.4006.1248995212.8015.python-list@python.org>
Message-ID: <008e7846$0$9756$c3e8da3@news.astraweb.com>

On Thu, 30 Jul 2009 18:06:31 -0500, Robert Kern wrote:

> On 2009-07-30 16:44, r wrote:
>> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com> wrote:
>>>> 1.) No need to use "()" to call a function with no arguments. Python
>>>> -->  "obj.m2().m3()" --ugly
>>>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
>>>> Man, i must admit i really like this, and your code will look so much
>>>> cleaner.
>>> It has benefits - code does look better. It has also significant cons
>>> - it is ambiguous.
>>> For instance:
>>>
>>> a = b
>>>
>>> Is b a variable or a method called without parameter?
>>
>> Hello Emanuel,
>> Again, who so ever names a method with such a non-descriptive name will
>> get whats coming to him. And if you did for some reason use such a
>> cryptic name as "b", do yourself (and everyone else) a favor and follow
>> it with "()" to denote the method call. Remember when something is
>> optional that means you have an option to use it OR not use it.
> 
> I believe his point is that it is ambiguous to the compiler, not humans
> reading the code. Python functions and methods are first class objects.
> They can be passed around. If they were auto-called, then you could not
> do this.

Oh my, "r" is still around is he??? And now he's singing the praises of 
Ruby, the language which he treated as the Devil's Spawn when he first 
arrived. That's hilarious.

But back on topic... "r" has missed the point. It's not that a=b is hard 
to understand because b is a poor name. The example could have been:

def factory_function():
    magic = time.time()  # or whatever
    def inner():
        return magic
    return inner

my_function = factory_function

It's still ambiguous. Does the programmer intend my_function to become 
factory_function itself, or the output of factory_function?

In Python, it's not ambiguous at all -- my_function is set to 
factory_function, and *not* the output of factory_function, because you 
haven't called the function.

Python's model is consistent and simple: given a function "func", you 
*always* refer to the function object itself as func and you *always* 
call it with func(). This applies no matter how many arguments the 
function takes, or what it returns, or where it is defined.

I think it's telling that "r" the fanboy has rejected Python's advantages 
(simplicity, consistency, unambiguity) in favour of lazily saving two 
keystrokes.



-- 
Steven


From lkrzysiak at gmail.com  Fri Jul 31 03:28:54 2009
From: lkrzysiak at gmail.com (=?UTF-8?Q?=C5=81ukasz?=)
Date: Fri, 31 Jul 2009 00:28:54 -0700 (PDT)
Subject: How to force SAX parser to ignore encoding problems
Message-ID: <89c214a4-e846-4101-b0b3-8078eec15114@w41g2000yqb.googlegroups.com>

Hi,
I have a problem with my XML parser (created with libraries from
xml.sax package). When parser finds a invalid character (in CDATA
section) for example ?, throws an exception SAXParseException.

Is there any way to just ignore this kind of problem. Maybe there is a
way to set up parser in less strict mode?

I know that I can catch this exception and determine if this is this
kind of problem and then ignore this, but I am asking about any global
setting.



From contact at xavierho.com  Fri Jul 31 03:34:32 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 17:34:32 +1000
Subject: problem on socket programming
In-Reply-To: <2d56febf0907310033n66afa69ch3a43bcbe078396c5@mail.gmail.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<2d56febf0907310033n66afa69ch3a43bcbe078396c5@mail.gmail.com>
Message-ID: <2d56febf0907310034kf012f4br2b8ef56688e2883c@mail.gmail.com>

Whoops, posted to the wrong address.... yet again.

I deserve some punishment.

On Fri, Jul 31, 2009 at 5:33 PM, Xavier Ho <contact at xavierho.com> wrote:

> On Fri, Jul 31, 2009 at 5:25 PM, MalC0de <malc0de.encrypt at gmail.com>wrote:
>
>>
>> while true :
>>
>> where's the problem,
>
>
> There. =]
>

(Btw, it's True, not true.)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/169f94fb/attachment-0001.html>

From efotinis at oohay.com  Fri Jul 31 03:38:41 2009
From: efotinis at oohay.com (eliasf)
Date: Fri, 31 Jul 2009 10:38:41 +0300
Subject: Test for Pythonwin?
In-Reply-To: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>
References: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>
Message-ID: <1249025993.67838@athprx04>

"steve" wrote:
> Is there a good way to check if a script is running inside Pythonwin?
> Perhaps a property or method that is exposed by that environment?

I don't know how foolproof it is, but this works:

    'pywin' in sys.modules



From piet at cs.uu.nl  Fri Jul 31 03:47:34 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 31 Jul 2009 09:47:34 +0200
Subject: Non-blocking read with popen subprocess
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
	<824f8092-55b1-4df2-a6b5-74a4b1b1d9ea@i18g2000pro.googlegroups.com>
Message-ID: <m2vdl9uwdl.fsf@cs.uu.nl>

>>>>> Jonathan Gardner <jgardner at jonathangardner.net> (JG) wrote:

>JG> On Jul 30, 5:24?pm, Dhanesh <dhanesh... at gmail.com> wrote:
>>> 
>>> how can I we have a non blocking read ?

>JG> See http://docs.python.org/library/popen2.html#flow-control-issues

>JG> Note well: In the non-blocking world, you have to use select() or poll
>JG> () to get your job done.

AFAIK, on Windows these work only on sockets, not on files. I think
pipes are in the files camp.

Alternatively you can read one of the two in a different thread.

>JG> You may want to look at "communicate" (http://docs.python.org/library/
>JG> subprocess.html#popen-objects) which may be what you need.

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From masklinn at masklinn.net  Fri Jul 31 03:48:24 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 09:48:24 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <op.uxwhp7jufvx12t@jerzozwiesz.home.aster.pl>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<d44977dc-2473-46e6-914c-1b218f32af85@d36g2000prb.googlegroups.com>
	<3B112998-E96D-40E0-9F2B-1ECC270BB9F5@masklinn.net>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<op.uxwhp7jufvx12t@jerzozwiesz.home.aster.pl>
Message-ID: <27BA9FDF-8295-41F5-A4E7-170B0D755159@masklinn.net>

On 30 Jul 2009, at 23:52 , Jan Kaliszewski wrote:
> Dnia 30-07-2009 o 22:41:57 Masklinn <masklinn at masklinn.net>  
> napisa?(a):
> On 30 Jul 2009, at 22:23 , Jan Kaliszewski wrote:
>>> 30-07-2009 o 13:36:49 Masklinn <masklinn at masklinn.net> wrote:
>>>> On 30 Jul 2009, at 06:04 , alex23 wrote:
>>>>> On Jul 30, 1:06 pm, r <rt8... at gmail.com> wrote:
>>>>>> 2.) the .each method
>>>>>> container.each{|localVar| block}
>>>>>> This method can really cleanup some ugly for loops, although i  
>>>>>> really
>>>>>> like the readability of for loops.
>>>>>
>>>>> map(lambda localVar: <block>, sequence)
>>>>>
>>>>> or:
>>>>>
>>>>> def usefully_named_func(var):
>>>>>  <block>
>>>>>  return var
>>>>>
>>>>> transformed = [usefully_named_func(v) for v in sequence]
>>>>>
>>>> The issue here is of course that `map` and comprehensions are  
>>>> transformations. `#each` exists for effectful iterations (Ruby  
>>>> has `#map` for the map operation). So the intent expressed by  
>>>> `#each` and `map` isn't the same. Furthermore and this is the  
>>>> most problematic limitation of Python here, `lambda` doesn't  
>>>> allow complex transformations due to its restrictions, so one has  
>>>> to switch to named functions which works but isn't sexy (and  
>>>> tends to lower readability imo).
>>>
>>> I don't see any real limitation. What's wrong in:
>>>
>>> for localVar in container:
>>>   block
>>>
>> Well what's wrong with using that rather than `map`, `filter` or a  
>> list comprehension? (and if you don't see what the limitations of  
>> `lambda` are, you probably very rarely use it)
>
> I know well about the expression-only-limitation of lambda, fortnately
> there is the 'for' loop construct (or, alternatively, you can define
> a named function).
>
> And then, what's wrong with using 'for' rather than 'map', 'filter'  
> etc.?
Nothing, but then again nothing's wrong using C's for either.

But I do think that using higher-order functions:
* tends to be terser while not going overly terse, it only removes  
boilerplate
* is more composable (it's pretty easy to tack another transformer in  
your chain, the same way defining iterator/generator transformers and  
chaining them is simpler than doing the same thing using explicit  
`for?in`)
* it clearly spells the intent of the programmer, while `for` can be  
anything and everything, and one has to dive into the code to know  
even the high-level operations performed (is it a basic  
transformation? A filtering or partitioning? A reduction? An  
application of side effects?)
> Agree, that 'anonymous block syntax' would be nice in some cases, but
> I don't see any real limitation caused by lack of it i.e. something  
> you
> can't (all you can only with unreasonable effort).
>
There are no limitations, but once again there never are. There are no  
actual limitations to using conditional jumps over iterators either.

>>> And ruby's container.each is very similar to Python's iter()
>
>> Uh? not at all?
>
> OK, .each is like Python's iter() + some form of iterating over it
> ('for' loop or '[i]map'...).
Well of course Enumerable#each is similar to map/imap, it's the same  
core principle.

From malc0de.encrypt at gmail.com  Fri Jul 31 03:50:19 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 00:50:19 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
Message-ID: <3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>

problem with this code solved in win32, but I didn't test it after
solved problem on gnu/linux .


From bieffe62 at gmail.com  Fri Jul 31 03:51:45 2009
From: bieffe62 at gmail.com (Francesco Bochicchio)
Date: Fri, 31 Jul 2009 00:51:45 -0700 (PDT)
Subject: socket send
References: <55aba832-df6d-455f-bf34-04d37eb061cd@i4g2000prm.googlegroups.com>
	<41b3e874-e10e-4760-8974-cc4988ba9803@w41g2000yqb.googlegroups.com> 
	<mailman.3992.1248984980.8015.python-list@python.org>
Message-ID: <45056c13-9ff6-4a0f-b357-1893d7d03144@s15g2000yqs.googlegroups.com>

On Jul 30, 10:16?pm, "Jan Kaliszewski" <z... at chopin.edu.pl> wrote:
> 30-07-2009 o 12:29:24 Francesco Bochicchio <bieff... at gmail.com> wrote:
>
> > On Jul 30, 5:52?am, NighterNet <darkne... at gmail.com> wrote:
> >> I am trying to figure out how to send text or byte in python 3.1. I am
> >> trying to send data to flash socket to get there. I am not sure how to
> >> work it.
>
> >> buff= 'id=' , self.id , ':balive=False\n'
> >> clientSock.send(buff);
>
> > Try putting a 'b' before the constant string that you want to send:
>
> > >>> type(b'123')
> > <class 'bytes'>
>
> It's true. In python '...' literals are for strings ('str' type) and
> b'...' literals are for binary data (bytes type).
>
> Sockets' send() and recv() need binary data ('bytes' objects).
>
> > or use something like this to convert non constant strings (with only
> > ASCII characters) into bytes:
> > >>> s = "A non-constant string : %d " % n
> > >>> s
> > 'A non-constant string : 12 '
> > >>> type(s)
> > <class 'str'>
>
> What???
>
> 'str' type in Python 3.x IS NOT a type of "non-constant" strings and
> IS NOT a type of strings "with only ASCII characters"!
>
> 'str' type in Python 3.x *is* the type of immutable ('constant') and
> Unicode character (Unicode, not only ASCII) strings. It's the same what
> 'unicode' type in Python 2.x.
>

... unfortunate choice of words and not enough research on my part
here. WHat I meant was: if you want
to send via socket a constant string, use b"..."; if you want to send
via socket  a string that you
made out of variables (the "non-constant string" ) then you have to
convert it in bytes. Since I did not
now of the encode method, I tried other solutions, like the one-liner
using ord or using the struct
module. Obviously, encode is better.

My bad :-)

Ciao
-------
FB


From malc0de.encrypt at gmail.com  Fri Jul 31 04:02:33 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 01:02:33 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
Message-ID: <e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>

now I've been encountered to some errors with this snippet :

import sys
from socket import *
serverHost = 'localhost'
serverPort = 50007
message = ['Hello network world']
if len(sys.argv) > 1:
    serverHost = sys.argv[1]
    if len(sys.argv) > 2:
        message = sys.argv[2:]
sockobj = socket(AF_INET,SOCK_STREAM)
sockobj.connect((serverHost,serverPort))
for line in message:
    sockobj.send(line)
    data = sockobj.recv(1024)
    print 'Client recieved :',repr(data)
sockobj.close()


thanks if someone can solve my problem .

- malc0de.


From matt.urry at googlemail.com  Fri Jul 31 04:04:08 2009
From: matt.urry at googlemail.com (ma3mju)
Date: Fri, 31 Jul 2009 01:04:08 -0700 (PDT)
Subject: Processes not exiting
Message-ID: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>

Hi all,

I'm having trouble with multiprocessing I'm using it to speed up some
simulations, I find for large queues when the process reaches the
poison pill it does not exit whereas for smaller queues it works
without any problems. Has anyone else had this trouble? Can anyone
tell me a way around it? The code is in two files below.

Thanks

Matt

parallel.py
===================================================
import GaussianProcessRegression as GP
import numpy as np
import networkx as nx
import pickle
import multiprocessing
############################################################################################
# Things You Can Change
############################################################################################
#savefiles
savefile = "wattsdata2"
graphfile = "wattsgraphs2"
#sample sizes
num_graphs = 5
num_sets_of_data = 10
#other things...
intervals = np.ceil(np.logspace(-2,1,50)*500)
noise = [np.sqrt(0.1),np.sqrt(0.01),np.sqrt(0.001),np.sqrt(0.0001)]

############################################################################################
#generate graphs
graphs  = []
for i in range(0,num_graphs):
    graphs.append(nx.watts_strogatz_graph(500,5,0.01))
#save them for later reference
filehandler = open(graphfile,'w')
pickle.dump(graphs,filehandler,-1)
filehandler.close()

#queues
easy_work_queue = multiprocessing.Queue()
hard_work_queue = multiprocessing.Queue()
result_queue = multiprocessing.Queue()
#construct the items in the hard queue
l=0
for j in range(0,len(intervals)):
    for i in range(0,len(noise)):
        for k in range(0,num_graphs):
            if int(intervals[j]) <=4000:
                easy_work_queue.put({'datapt': l,'graph': graphs
[k],'noise': noise[i],'number_of_sets_of_data':
num_sets_of_data,'number_of_data_points':int(intervals[j])})
            else:
                hard_work_queue.put({'datapt': l,'graph': graphs
[k],'noise': noise[i],'number_of_sets_of_data':
num_sets_of_data,'number_of_data_points':int(intervals[j])})
            l+=1

#get number of cores and set the number on concurrent processes
num_hard_workers = 2
num_workers = multiprocessing.cpu_count()*1.5
easy_workers = []
hard_workers = []
#add poison pill for each worker and create the worker
for i in range(0,num_workers-num_hard_workers):
    easy_work_queue.put(None)
    easy_workers.append(multiprocessing.Process
(target=GP.RandomWalkGeneralizationErrorParallel,args=
(easy_work_queue,result_queue,)))
for i in range(0,num_hard_workers):
    hard_work_queue.put(None)
    hard_workers.append(multiprocessing.Process
(target=GP.RandomWalkGeneralizationErrorParallel,args=
(hard_work_queue,result_queue,)))

#run all workers
for worker in hard_workers:
    worker.start()
for worker in easy_workers:
    worker.start()
#wait for easy workers to finish
for worker in easy_workers:
    worker.join()
    print('worker joined')

#set off some of the easy workers on the hard work (maybe double
number of hard)
for i in range(0,num_hard_workers):
    hard_work_queue.put(None)
    hard_workers.append(multiprocessing.Process
(target=GP.RandomWalkGeneralizationErrorParallel,args=
(hard_work_queue,result_queue,)))
#wait for all hard workers to finish
for worker in hard_workers:
    worker.join()

#construct data from the mess in the result queue

tempdata = np.zeros(l)
while not result_queue.empty():
    data = result_queue.get()
    tempdata[data[0]] = data[1]

finaldata = tempdata.reshape((len(intervals),len(noise),num_graphs))

np.save(savefile,finaldata)

=======================================================
GaussianProcessRegression.py
=======================================================
import CovarianceFunction as CF
import networkx as nx
import numpy as np
import scipy.linalg as sp
#fortran code from lapack-blas (hopefully when scipy updated this wont
be needed)
import dtrsv
#to use more than one core
import multiprocessing

#Currently we assume Gaussian noise TODO change to general noise
#Assume 0 mean TODO change to general mean Gaussian Process
class GaussianProcessRegression:
    def __init__(self,covariance_function,sigma):
        #a covariance function object defined in CovarianceFunction
class
        #note this uses the parent class but any children can be used
        self.C = covariance_function
        #a list of pts that are known and their values
        self.pts = []
        self.vals = []
        #the inverse of K as defined in
        #@book{coolen05:theoryofneural,
	    #ISBN = {0-19-853024-2},
	    #publisher = {Oxford University Press, USA},
	    #author = {Coolen, A. C. C. and K{\"{u}}hn, R. and Sollich, P.},
	    #title = {Theory of neural information processing systems},
	    #year = {2005},
        #}
        self.K = np.array([])
        #gaussian noise variable
        self.sigma = float(sigma)
        self.cholL = np.array([])


    def add_data_points(self,points,vals):
       #add all points to list
       self.pts += points
       self.vals += vals
       arraysize = len(self.pts)
       #construct K
       K = np.zeros((arraysize,arraysize))
       #for speed
       pts = self.pts
       between_points = self.C.between_points
       if len(self.K):
            K[:-1,:-1] = self.K
       for i in xrange(0,arraysize):
           for j in xrange(arraysize-len(points),arraysize):
                 K[i,j] = between_points(pts[i],pts[j])
                 K[j,i] = K[i,j]
       K[arraysize-len(points):arraysize,arraysize-len
(points):arraysize] =  K[arraysize-len(points):arraysize,arraysize-len
(points):arraysize] + self.sigma**2 * np.eye(len(points))
       self.K = K

    #calculate the prediction of a point based on data previously
given
    def point_prediction(self,points):
        mean = []
        variance =[]
        arraysize = len(self.pts)
        #cholesky
        #if self.cholL.shape[0] < arraysize:
        L=np.linalg.cholesky(self.K)
        #    self.cholL = L
        #else:
        #    L = self.cholL

        alpha = sp.cho_solve((L,1),self.vals)
        #create L in banded form
        k=np.zeros((arraysize,len(points)))
 
##################################################################
        #for speed get ref to functions im going to use and save them
        between_points = self.C.between_points
        pts = self.pts
        dot = np.dot
 
##################################################################
        for j in xrange(0,len(points)):
            #create k
            for i in xrange(0,arraysize):
                k[i,j] = between_points(pts[i],points[j])

        #calculate mean and variance
        #call the command for forward substitution
        ###############fortran
call#######################################
        v = dtrsv.dtrsv('L','N',arraysize,L,k)
 
##################################################################

        #result
        mean=dot(alpha,k)
        for i in xrange(0,len(points)):
            variance.append(between_points(points[i],points[i]) - dot(v
[:,i],v[:,i]))
        #return it in dictionary form
        return {'mean':mean,'variance':variance}


    # calculate the error for data given, where function is a vector
    # of the function evaluated at a sufficiently large number of
points
    # that the GPregression has been trying to learn
    def error(self,function):
        total = 0
        #sum up variances
        result = self.point_prediction(function[::2])
        total = np.sum(result['variance'])
        total = (1/float(len(function)/2))*total
        return total

    #clear what has been learnt so far
    def clear(self):
        self.pts = []
        self.vals = []
        self.K = np.array([])

    #calculate the average error for a function defined in function
when give
    #number_of_examples examples
    def average_error_over_samples(self,function, sample_size,
number_of_examples):
        avg = 0
        numberofpoints = len(function)/2
        for i in range(0,sample_size):
            self.clear()
            #generate points of the function
            permpts = np.random.randint
(0,numberofpoints,number_of_examples)
            #create the vectors
            pts = []
            vals = []
            for j in range(0,number_of_examples):
                pts.append(function[permpts[j]*2])
                vals.append(function[permpts[j]*2+1])

            #learn these points
            self.add_data_points(pts,vals)
            #print("points added")
            avg = avg + self.error(function)
        avg = avg/sample_size
        return avg

    #calculate the average error over functions over data of size
number_of_data_points for MOST cases this is
    #also the generalization error a summary of which and
approximations to can be found in:
    #@inproceedings{Sollich99learningcurves,
	#booktitle = {Neural Computation},
	#author = {Sollich, P.},
	#title = {Learning curves for Gaussian process regression:
Approximations and bounds},
	#pages = {200-2},
	#year = {1999},
    #}

    def emprical_average_error_over_functions
(self,number_of_functions,number_of_sets_of_data,number_of_data_points,function_detail
=0,progress=0):
        avg = 0
        step = float(100)/number_of_functions
        for i in range(0,number_of_functions):
            if progress:
                print step*float(i),"%"
            if function_detail:
                fx = self.C.generate_function
(self.sigma,function_detail)
            else:
                fx = self.C.generate_function(self.sigma)
            avg = self.average_error_over_samples
(fx,number_of_sets_of_data,number_of_data_points)+avg
        avg = avg / number_of_functions
        return avg

    def average_error_over_functions
(self,number_of_sets_of_data,number_of_data_points,function_detail=0):
            if function_detail:
                fx = self.C.generate_function
(self.sigma,function_detail)
            else:
                fx = self.C.generate_function(self.sigma)
            avg = self.average_error_over_samples
(fx,number_of_sets_of_data,number_of_data_points)
            return(avg)



    def function_prediction(self,pts):
        temp = self.point_prediction(pts)
        return {'func':temp['mean'],'varpos':temp
['variance'],'varneg':-temp['variance']}


#########################################################################################################################################################
#Functions not contained in a class
#########################################################################################################################################################

#function to calculate the generalization error for a RandomWalk
kernel averaging over graphs graphs
def RandomWalkGeneralizationError
(noise,graphs,number_of_sets_of_data,number_of_data_points,a=2,p=10):
    graph_specific = np.zeros(len(graphs))
    avg = 0
    for i in range(0,len(graphs)):
        rw = CF.RandomWalk(a,p,graphs[i])
        GP = GaussianProcessRegression(rw,noise)
        graph_specific[i] = GP.average_error_over_functions
(number_of_sets_of_data,number_of_data_points)
    avg = np.sum(graph_specific)/len(graphs)
    return avg, graph_specific

#as above but using queues to create parallel architechture
def RandomWalkGeneralizationErrorParallel
(work_queue,result_queue,a=2,p=10):
    while True:
        input = work_queue.get()
        if input is None:
            print "poison"
            break
            print 'this should not appear'
        print input['datapt'], ' ', input['number_of_data_points']
        rw=CF.RandomWalk(a,p,input['graph'])
        GP = GaussianProcessRegression(rw,input['noise'])
        err = GP.average_error_over_functions(input
['number_of_sets_of_data'],input['number_of_data_points'])
        result_queue.put([input['datapt'],err])
    print 'here'
    return


From matt.urry at googlemail.com  Fri Jul 31 04:06:25 2009
From: matt.urry at googlemail.com (ma3mju)
Date: Fri, 31 Jul 2009 01:06:25 -0700 (PDT)
Subject: Processes not exiting
References: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
Message-ID: <28791ddd-5270-4a74-9c86-8fe719b34069@d4g2000yqa.googlegroups.com>

Sorry

###############fortran
call#######################################

 is meant to be

###############fortran call#######################################

Matt


From clp2 at rebertia.com  Fri Jul 31 04:07:41 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 01:07:41 -0700
Subject: problem on socket programming
In-Reply-To: <e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
Message-ID: <50697b2c0907310107v40f20d51ic5852303e545cd77@mail.gmail.com>

On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encrypt at gmail.com> wrote:
> now I've been encountered to some errors with this snippet :

And these errors are? Provide error messages and full tracebacks.

Cheers,
Chris
-- 
http://blog.rebertia.com


From masklinn at masklinn.net  Fri Jul 31 04:08:33 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 10:08:33 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <200907301757.48761.kyrie@uh.cu>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
Message-ID: <FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>

On 30 Jul 2009, at 23:57 , Luis Zarrabeitia wrote:
> I'd like to ask, what "container.each" is, exactly? It looks like a  
> function
> call (as I've learned a few posts ago), but, what are its arguments?  
> How the
> looping "works"? Does it receive a "code" object that it has to  
> execute?
> Is .each some kind of magic keyword? (This has little to do with  
> python or
> the current thread, so feel free to reply off-list if you want to...)

#each is simply a method that takes a function (called blocks in  
ruby). One could call it a higher-order method I guess.

It's an implementation of the concept of internal iteration: instead  
of collections yielding iterator objects, and programmers using those  
through specially-built iteration constructs (e.g. `for?in`),  
collections control iteration over themselves (the iteration is  
performed "inside" the collection, thus the "internal" part) and the  
programmer provides the operations to perform at each iterative step  
through (usually) a function.

In Python (assuming we had anonymous defs and an each method on  
lists), the following loop:

     for item in some_list:
         do_something(item)
         do_something_else(item)

     some_list.each((def (item):
         do_something(item)
         do_something_else(item)
     ))

There's absolutely nothing magic there, it's simply using anonymous  
functions and method calls (SmallTalk initiated this approach in the  
70s, and actually went much, much further than Ruby as it did away not  
only with `for?in` but also with `if?else` and `while` and a bunch of  
other stuff).

Now as IV pointed out, #each isn't the most interesting usage of  
blocks/anonymous functions (though I do like it, because it gets rid  
of no less than two keywords? even if Ruby reintroduced them as  
syntactic sugar), higher-order functions (functions which act on other  
functions) are (among other things) ways to create new control  
structures without having to extend the core language (so are lisp- 
style macros, by the way).

Of course Python does have higher-order functions (functions are first- 
class objects, so it's possible and frequent to have functions act on  
other functions), but since Python doesn't have anonymous functions  
that usage tends to be a bit too verbose beyond simple cases (also, of  
course, this kind of usages is neither in the "genes" nor in the  
stdlib).

In closing, IV has an example of how blocks make `with` unnecessary in  
Ruby (the functionality can be implemented at the library level rather  
than the language one). Generally, anonymous functions in OO languages  
are a way to inject behavior into third-party methods/objects. Kind-of  
a first-class Visitor support.

-m

PS: there's actually a bit of syntactic magic in Ruby's blocks, and  
it's one of the things I hate in the language, but it's not relevant  
to the role of blocks, and unnecessary to it: SmallTalk has no magical  
syntax).

From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 04:13:50 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 08:13:50 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
Message-ID: <008e82e8$0$9756$c3e8da3@news.astraweb.com>

On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:

> That and the fact that I couldn't stop laughing for long enough to learn
> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
> unlike less flexible languages, lets you alter the value of a constant."
> Yep, as they say "Bug" = "Undocumented feature"!

That's no different from Python's "constant by convention". We don't even 
get a compiler warning!

On the other hand, we don't have to prefix names with @ and @@, and we 
don't have the compiler trying to *guess* whether we're calling a 
function or referring to a variable.

Somebody who knows more Ruby than me should try writing the Zen of Ruby. 
Something like:

Line noise is beautiful.
Simplicity is for the simple.
Complicated just proves we're smart.
Readability only matters to the schmuck who has to maintain our code.
Special cases require breaking the rules.
In the face of ambiguity, try to guess. Go on, what could go wrong?
The more ways to do it, the better.

Although I'm sure Ruby has its good points. I'm not convinced anonymous 
code blocks are one of them though.


-- 
Steven


From hendrik at microcorp.co.za  Fri Jul 31 04:18:15 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 31 Jul 2009 10:18:15 +0200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <7dca4iF2bgbn5U1@mid.individual.net>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>
	<mailman.3879.1248854780.8015.python-list@python.org>
	<7dca4iF2bgbn5U1@mid.individual.net>
Message-ID: <200907311018.15784.hendrik@microcorp.co.za>

On Thursday 30 July 2009 03:09:14 greg wrote:
> Hendrik van Rooyen wrote:
> > And if code is data, where is Pythons ALTER statement?
>
> class Duck:
>
>    def quack(self):
>      print "Quack!"
>
> def moo():
>    print "Moo!"
>
> def ALTER(obj, name, TO_PROCEED_TO):
>    setattr(obj, name, TO_PROCEED_TO)
>
> d = Duck()
> ALTER(d, 'quack', TO_PROCEED_TO = moo)
> d.quack()

Nice, and I really appreciate the Duck, 
but (there is always a but):

1) That is a function, not a statement.

2) The original changed a jump target address from
one address to another, and did not need the
heavy machinery of object oriented code.

So what you are doing is not quite the same.

It is actually not really needed in python, as
one can pass functions around, so that you can
call different things instead of jumping to them:

thing_to_call = moo
thing_to_call()

Does the equivalent without user level OO.

The original ALTER statement found use in building
fast state machines, where the next thing to do was
set up by the current state.  In python one simply returns
the next state.

The equivalent python code is easier to read as it is 
obvious what is happening - The COBOL source was
more obscure, as any jump could have been altered,
and you could not see that until you have read further
on in the program, where the ALTER statement was.

- Hendrik


From contact at xavierho.com  Fri Jul 31 04:21:45 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 18:21:45 +1000
Subject: Confessions of a Python fanboy
In-Reply-To: <FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
Message-ID: <2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <masklinn at masklinn.net> wrote:

> <snip>... but since Python doesn't have anonymous functions that usage
> tends to be a bit too verbose ... <snip>
>

Sorry to interrupt, but wouldn't lambda in Python be considered as
'anonymous functions'?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/f8e80b3e/attachment-0001.html>

From clp2 at rebertia.com  Fri Jul 31 04:25:37 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 01:25:37 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
Message-ID: <50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>

On Fri, Jul 31, 2009 at 1:21 AM, Xavier Ho<contact at xavierho.com> wrote:
> On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <masklinn at masklinn.net> wrote:
>>
>> <snip>... but since Python doesn't have anonymous functions that usage
>> tends to be a bit too verbose ... <snip>
>
> Sorry to interrupt, but wouldn't lambda in Python be considered as
> 'anonymous functions'?

I believe "full" anonymous functions was intended by the author.
lambdas are limited to a single expression. "Full" anonymous functions
would be allowed to contain multiple statements.

Cheers,
Chris
-- 
http://blog.rebertia.com


From javier.collado at gmail.com  Fri Jul 31 04:27:01 2009
From: javier.collado at gmail.com (Javier Collado)
Date: Fri, 31 Jul 2009 10:27:01 +0200
Subject: Non-blocking read with popen subprocess
In-Reply-To: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
Message-ID: <c83cde5a0907310127x744e08e2rdefa402a1834c4a4@mail.gmail.com>

Hello,

According to my experience and from what I've read in other threads,
subprocess isn't easy to use for interactive tasks. I don't really
know, but maybe it wasn't even designed for that at all.

On the other hand, pexpect seems to work fine for interactive use and
even provides a method for nonblocking reads, so I think that you
should consider to take a look at it:
http://pexpect.sourceforge.net/pexpect.html#spawn-read_nonblocking

Best regards,
    Javier

2009/7/31 Dhanesh <dhaneshpai at gmail.com>:
> Hi ,
>
> I am trying to use subprocess popen on a windows command line
> executable with spits messages on STDOUT as well as STDIN. Code
> snippet is as below :-
> ##########################################################################
> sOut=""
> ? ?sErr=""
> ? ?javaLoaderPath = os.path.join("c:\\","Program Files","Research In
> Motion","BlackBerry JDE 4.7.0","bin","Javaloader.exe")
> ? ?cmd = [javaLoaderPath,'-u','load','helloworld.jad']
> ? ?popen = subprocess.Popen
> (cmd,bufsize=256,shell=False,stdout=subprocess.PIPE,
> stderr=subprocess.PIPE)
> ? ?while True:
> ? ? ? ?sErr = sErr + popen.stderr.read(64)
> ? ? ? ?sOut = sOut + popen.stdout.read(64)------------------> Blocks
> here
> ? ? ? ?if None != popen.poll():
> ? ? ? ? ? ?break;
> ##########################################################################
>
> I observed that python scripts blocks at stdout read on the other hand
> when I do not create a child stdout PIPE ?say ?" stdout=None" , things
> seems to be working fine.
>
> how can I we have a non blocking read ?
> And why does stdout block even where data is available to be read
> ( which seem to be apparent when stdout=None, and logs appear on
> parents STDOUT) ?
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From contact at xavierho.com  Fri Jul 31 04:31:43 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 18:31:43 +1000
Subject: Confessions of a Python fanboy
In-Reply-To: <50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
Message-ID: <2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:25 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> I believe "full" anonymous functions was intended by the author.
> lambdas are limited to a single expression. "Full" anonymous functions
> would be allowed to contain multiple statements.
>
> Cheers, but what about this:

 def goBig(x):
    while True:
        x = x ** 2
        yield x

for result in goBig(10):
    if result > 10 ** 100:
        break
    print result

It's a silly example, but wouldn't goBig(10) in this example be a "full
anonymous function"?

Just being curious.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/df0d8a3a/attachment-0001.html>

From clp2 at rebertia.com  Fri Jul 31 04:38:16 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 01:38:16 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
	<2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>
Message-ID: <50697b2c0907310138u1ea485f9yf9bac0095e09927d@mail.gmail.com>

On Fri, Jul 31, 2009 at 1:31 AM, Xavier Ho<contact at xavierho.com> wrote:
> On Fri, Jul 31, 2009 at 6:25 PM, Chris Rebert <clp2 at rebertia.com> wrote:
>>
>> I believe "full" anonymous functions was intended by the author.
>> lambdas are limited to a single expression. "Full" anonymous functions
>> would be allowed to contain multiple statements.
>>
> Cheers, but what about this:
>
> ?def goBig(x):
> ??? while True:
> ??????? x = x ** 2
> ??????? yield x
>
> for result in goBig(10):
> ??? if result > 10 ** 100:
> ??????? break
> ??? print result
>
> It's a silly example, but wouldn't goBig(10) in this example be a "full
> anonymous function"?

No, because it has a name, namely "goBig"; this obviously prevents it
from being "anonymous".

For comparison, note how the function in the following example is
never given a name, and is thus anonymous:
>>> (lambda x: x+5)(6)
11

Cheers,
Chris
-- 
http://blog.rebertia.com


From malc0de.encrypt at gmail.com  Fri Jul 31 04:38:21 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 01:38:21 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
Message-ID: <67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>

On Jul 31, 12:07?pm, Chris Rebert <c... at rebertia.com> wrote:
> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
> > now I've been encountered to some errors with this snippet :
>
> And these errors are? Provide error messages and full tracebacks.
>
> Cheers,
> Chris
> --http://blog.rebertia.com

these are errors :

Traceback (most recent call last):
  File "echo-client.py", line 11, in <module
    sockobj.connect((serverHost,serverPort))
  File "<string>", line 1, in connect
socket.error: (10061, 'Connection refused')


From contact at xavierho.com  Fri Jul 31 04:41:17 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 18:41:17 +1000
Subject: Confessions of a Python fanboy
In-Reply-To: <50697b2c0907310138u1ea485f9yf9bac0095e09927d@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
	<2d56febf0907310131x6d83f647i173f084c240a5ca3@mail.gmail.com>
	<50697b2c0907310138u1ea485f9yf9bac0095e09927d@mail.gmail.com>
Message-ID: <2d56febf0907310141m15bfc526i3c916f5a2b48f544@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:38 PM, Chris Rebert <clp2 at rebertia.com> wrote:

> No, because it has a name, namely "goBig"; this obviously prevents it
> from being "anonymous".
>
> For comparison, note how the function in the following example is
> never given a name, and is thus anonymous:
> >>> (lambda x: x+5)(6)
> 11
>

Oh, I see. I was thinking in terms of using a variable to "give the function
a name". In that case, I understand. Thanks again for bearing me with my
random thoughts.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/9c3f4d35/attachment-0001.html>

From hendrik at microcorp.co.za  Fri Jul 31 04:47:24 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 31 Jul 2009 10:47:24 +0200
Subject: Does python have the capability for driver development ?
In-Reply-To: <4A719E2D.708@ieee.org>
References: <DdCdnUGX7sw-SO3XnZ2dnUVZ8hmdnZ2d@bt.com>
	<sOydnT6s_a_ByezXnZ2dnUVZ8ili4p2d@bt.com> <4A719E2D.708@ieee.org>
Message-ID: <200907311047.25029.hendrik@microcorp.co.za>

On Thursday 30 July 2009 15:20:45 Dave Angel wrote:

> As far as I know, nobody has yet built a microcode implementation of a
> Python VM (Virtual Machine).  Nor have I seen one for the Java VM.

Atmel has made an ARM that has support for Java Bytecode.

AT91SAM9X512 and friends (smaller versions)

- Hendrik


From greg at cosc.canterbury.ac.nz  Fri Jul 31 05:02:08 2009
From: greg at cosc.canterbury.ac.nz (greg)
Date: Fri, 31 Jul 2009 21:02:08 +1200
Subject: If Scheme is so good why MIT drops it?
In-Reply-To: <mailman.4022.1249028151.8015.python-list@python.org>
References: <b0g665llur83sj9dnumktjvnipacj7bgrt@4ax.com>	<mailman.3879.1248854780.8015.python-list@python.org>	<7dca4iF2bgbn5U1@mid.individual.net>
	<mailman.4022.1249028151.8015.python-list@python.org>
Message-ID: <7dfq78F2c8bolU1@mid.individual.net>

Hendrik van Rooyen wrote:
> The COBOL source was
> more obscure, as any jump could have been altered,
> and you could not see that until you have read further
> on in the program, where the ALTER statement was.

Well, in Python you can pretty much replace any
function with any other function, so you can
obfuscate things just as much if you really want!

-- 
Greg


From jeanmichel at sequans.com  Fri Jul 31 05:20:47 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 31 Jul 2009 11:20:47 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <80839e72-9df4-4590-b22d-4c5c829e37b6@h11g2000yqb.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<mailman.4003.1248991082.8015.python-list@python.org>
	<80839e72-9df4-4590-b22d-4c5c829e37b6@h11g2000yqb.googlegroups.com>
Message-ID: <4A72B76F.4020805@sequans.com>

r wrote:
> The purpose of his thread was to get feedback on how Python
> and Ruby ideas could be cumulated into the best high level language.
> And being that i am the BDFL of the "Confessions of a Python Fanboy"
> thread, you have my personal permission to continue on with this
> subject matter...,
>
>   
Challenging even the most accepted mechanisms of a language is a proof 
of intelligence.

Descartes's doubt method :
"The basic strategy of /Descartes/ 
<http://www.philosophypages.com/ph/desc.htm>'s method of doubt 
<http://www.philosophypages.com/dy/d9.htm#doubt> is to defeat skepticism 
<http://www.philosophypages.com/dy/s5.htm#skep> on its own ground. Begin 
by doubting the truth of everything?not only the evidence 
<http://www.philosophypages.com/dy/e9.htm#evid> of the senses and the 
more extravagant cultural presuppositions, but even the fundamental 
process of reasoning itself. If any particular truth about the world can 
survive this extreme skeptical challenge, then it must be truly 
indubitable and therefore a perfectly certain foundation for knowledge"

So let's make the method call parenthesis a "truly indubitable and 
therefore a perfectly certain foundation".

Those who want to remove the parenthesis on python method calls raise 
the hand !

JM


From pyvault2.6 at gmail.com  Fri Jul 31 05:25:17 2009
From: pyvault2.6 at gmail.com (learner learner)
Date: Fri, 31 Jul 2009 14:55:17 +0530
Subject: file comparison
Message-ID: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>

Hi all,

I want to compare two text files line by line and eliminate the
matching/repeated line and store the unmatched/leftout lines into a third
file or overwrite into one of them.

regards
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/d9f3d5c1/attachment-0001.html>

From lkrzysiak at gmail.com  Fri Jul 31 05:29:57 2009
From: lkrzysiak at gmail.com (=?UTF-8?Q?=C5=81ukasz?=)
Date: Fri, 31 Jul 2009 02:29:57 -0700 (PDT)
Subject: How to force SAX parser to ignore encoding problems
References: <89c214a4-e846-4101-b0b3-8078eec15114@w41g2000yqb.googlegroups.com>
Message-ID: <5587c712-1a15-4666-a5d9-5c99ace648f6@a13g2000yqc.googlegroups.com>

On 31 Lip, 09:28, ?ukasz <lkrzys... at gmail.com> wrote:
> Hi,
> I have a problem with my XML parser (created with libraries from
> xml.sax package). When parser finds a invalid character (in CDATA
> section) for example ,

After sending this message I noticed that example invalid characters
are not displaying on some platforms :)



From shearichard at gmail.com  Fri Jul 31 05:30:36 2009
From: shearichard at gmail.com (northof40)
Date: Fri, 31 Jul 2009 02:30:36 -0700 (PDT)
Subject: Python 2.6 in shared/VPS environment
References: <6babf860-0161-4c1a-82f8-69e03dc53da0@p36g2000prn.googlegroups.com>
Message-ID: <923e59f8-638c-4c2e-8b6a-b6e13d415424@j9g2000prh.googlegroups.com>

Ignore this question. Managed to get Amazon Web Services going and
have installed Python 2.6 on there. Thanks for your eyeballs time.

On Jul 31, 7:09?pm, northof40 <shearich... at gmail.com> wrote:
> Hi - I'd really like to have access to Python 2.6 to try something
> out. It needs to be on Linux/Unix machine. I don't mind paying but
> whichever way I turn I find Python 2.4 is the standard installation.
>
> Anyone know of anyone who offers this out of the box ? Or got any
> smart way of achieving it ?
>
> thanks
>
> R.



From contact at xavierho.com  Fri Jul 31 05:34:58 2009
From: contact at xavierho.com (Xavier Ho)
Date: Fri, 31 Jul 2009 19:34:58 +1000
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <2d56febf0907310234h5bda3a66m66f71201efb92fe8@mail.gmail.com>

On Fri, Jul 31, 2009 at 7:25 PM, learner learner <pyvault2.6 at gmail.com>wrote:

> Hi all,
>
> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a third
> file or overwrite into one of them.
>

Sounds like homework to me. Why not look into:

- the file() function and its methods.

It's in the documentation.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/ab6e2777/attachment-0001.html>

From gh at ghaering.de  Fri Jul 31 05:35:03 2009
From: gh at ghaering.de (=?ISO-8859-1?Q?Gerhard_H=E4ring?=)
Date: Fri, 31 Jul 2009 11:35:03 +0200
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <h4uds7$8p2$1@ger.gmane.org>

learner learner wrote:
> Hi all,
>  
> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a
> third file or overwrite into one of them.

gl & hf!



From clp2 at rebertia.com  Fri Jul 31 05:37:25 2009
From: clp2 at rebertia.com (Chris Rebert)
Date: Fri, 31 Jul 2009 02:37:25 -0700
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <50697b2c0907310237y2c79e938g70952e966b74ce87@mail.gmail.com>

On Fri, Jul 31, 2009 at 2:25 AM, learner learner<pyvault2.6 at gmail.com> wrote:
> Hi all,
>
> I?want to compare two text files line by line and eliminate the
> matching/repeated?line and store the unmatched/leftout lines into?a third
> file or overwrite into one of them.

See the `difflib` module:
http://docs.python.org/library/difflib.html

Cheers,
Chris
-- 
http://blog.rebertia.com


From duncan.booth at invalid.invalid  Fri Jul 31 05:41:34 2009
From: duncan.booth at invalid.invalid (Duncan Booth)
Date: 31 Jul 2009 09:41:34 GMT
Subject: Generators through the C API
References: <mailman.4015.1249008960.8015.python-list@python.org>
Message-ID: <Xns9C596B31CD31Bduncanbooth@127.0.0.1>

Lucas P Melo <lukepadawan at gmail.com> wrote:

> Hello, I'm a total noob about the C API. Is there any way to create a 
> generator function using the C API? I couldn't find anything like the 
> 'yield' keyword in it.
> 
> Thanks in advance.

You define a new type with tp_flags including Py_TPFLAGS_HAVE_ITER. 
Anything that would be a local variable in your generator needs to become 
an attribute in the type.

The tp_init initialization function should contain all the code up to the 
first yield, tp_iter should return self and tp_iternext should execute code 
up to the next yield.

-- 
Duncan Booth http://kupuguy.blogspot.com


From masklinn at masklinn.net  Fri Jul 31 05:49:31 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 11:49:31 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com>
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com>
Message-ID: <C497400A-9853-4344-91D4-0A82ABF717DF@masklinn.net>

On 31 Jul 2009, at 10:25 , Chris Rebert wrote:
> On Fri, Jul 31, 2009 at 1:21 AM, Xavier Ho<contact at xavierho.com>  
> wrote:
>> On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <masklinn at masklinn.net>  
>> wrote:
>>>
>>> <snip>... but since Python doesn't have anonymous functions that  
>>> usage
>>> tends to be a bit too verbose ... <snip>
>>
>> Sorry to interrupt, but wouldn't lambda in Python be considered as
>> 'anonymous functions'?
>
> I believe "full" anonymous functions was intended by the author.
> lambdas are limited to a single expression.
Yes, and they're limited to a single *expression*, so before Python 3,  
lambda: print "foo" is out. Likewise, it isn't possible to have an if/ 
else statement within a lambda (though a ternary is ok), or a with, ?  
since Python statements aren't expressions.

From iainking at gmail.com  Fri Jul 31 05:54:50 2009
From: iainking at gmail.com (Iain King)
Date: Fri, 31 Jul 2009 02:54:50 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<mailman.4006.1248995212.8015.python-list@python.org>
	<008e7846$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <a46c8c91-a45d-43fe-aa16-f6e4df2201bb@d4g2000yqa.googlegroups.com>

On Jul 31, 8:28?am, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Thu, 30 Jul 2009 18:06:31 -0500, Robert Kern wrote:
> > On 2009-07-30 16:44, r wrote:
> >> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com> wrote:
> >>>> 1.) No need to use "()" to call a function with no arguments. Python
> >>>> --> ?"obj.m2().m3()" --ugly
> >>>> ? ?Ruby --> ?"obj.m1.m2.m3" ?-- sweeet!
> >>>> Man, i must admit i really like this, and your code will look so much
> >>>> cleaner.
> >>> It has benefits - code does look better. It has also significant cons
> >>> - it is ambiguous.
> >>> For instance:
>
> >>> a = b
>
> >>> Is b a variable or a method called without parameter?
>
> >> Hello Emanuel,
> >> Again, who so ever names a method with such a non-descriptive name will
> >> get whats coming to him. And if you did for some reason use such a
> >> cryptic name as "b", do yourself (and everyone else) a favor and follow
> >> it with "()" to denote the method call. Remember when something is
> >> optional that means you have an option to use it OR not use it.
>
> > I believe his point is that it is ambiguous to the compiler, not humans
> > reading the code. Python functions and methods are first class objects.
> > They can be passed around. If they were auto-called, then you could not
> > do this.
>
> Oh my, "r" is still around is he??? And now he's singing the praises of
> Ruby, the language which he treated as the Devil's Spawn when he first
> arrived. That's hilarious.
>
> But back on topic... "r" has missed the point. It's not that a=b is hard
> to understand because b is a poor name. The example could have been:
>
> def factory_function():
> ? ? magic = time.time() ?# or whatever
> ? ? def inner():
> ? ? ? ? return magic
> ? ? return inner
>
> my_function = factory_function
>
> It's still ambiguous. Does the programmer intend my_function to become
> factory_function itself, or the output of factory_function?

Not only that - does 'return inner' return the function inner or the
result of function inner?

How does ruby pass a function as an object?

Iain


From piet at cs.uu.nl  Fri Jul 31 06:01:09 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 31 Jul 2009 12:01:09 +0200
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
Message-ID: <m2r5vxuq6y.fsf@cs.uu.nl>

>>>>> MalC0de <malc0de.encrypt at gmail.com> (M) wrote:

>M> On Jul 31, 12:07?pm, Chris Rebert <c... at rebertia.com> wrote:
>>> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
>>> > now I've been encountered to some errors with this snippet :
>>> 
>>> And these errors are? Provide error messages and full tracebacks.
>>> 
>>> Cheers,
>>> Chris
>>> --http://blog.rebertia.com

>M> these are errors :

>M> Traceback (most recent call last):
>M>   File "echo-client.py", line 11, in <module
>M>     sockobj.connect((serverHost,serverPort))
>M>   File "<string>", line 1, in connect
>M> socket.error: (10061, 'Connection refused')

Is your server running?
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From piet at cs.uu.nl  Fri Jul 31 06:27:31 2009
From: piet at cs.uu.nl (Piet van Oostrum)
Date: Fri, 31 Jul 2009 12:27:31 +0200
Subject: Processes not exiting
References: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
Message-ID: <m2my6luoz0.fsf@cs.uu.nl>

>>>>> ma3mju <matt.urry at googlemail.com> (m) wrote:

>m> Hi all,
>m> I'm having trouble with multiprocessing I'm using it to speed up some
>m> simulations, I find for large queues when the process reaches the
>m> poison pill it does not exit whereas for smaller queues it works
>m> without any problems. Has anyone else had this trouble? Can anyone
>m> tell me a way around it? The code is in two files below.

How do you know it doesn't exit. You haven't shown any of your output.

I did discover a problem in your code, but it should cause an exception:

>m> #set off some of the easy workers on the hard work (maybe double
>m> number of hard)
>m> for i in range(0,num_hard_workers):
>m>     hard_work_queue.put(None)
>m>     hard_workers.append(multiprocessing.Process
>m> (target=GP.RandomWalkGeneralizationErrorParallel,args=
>m> (hard_work_queue,result_queue,)))
>m> #wait for all hard workers to finish
>m> for worker in hard_workers:
>m>     worker.join()

Here you create new hard workers, but you never start them. The join
should then give an exception when it reaches these.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org


From masklinn at masklinn.net  Fri Jul 31 06:32:56 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 12:32:56 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <a46c8c91-a45d-43fe-aa16-f6e4df2201bb@d4g2000yqa.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3999.1248989365.8015.python-list@python.org>
	<23d07b28-8cb9-4297-bd02-af4f59f99334@n11g2000yqb.googlegroups.com>
	<mailman.4006.1248995212.8015.python-list@python.org>
	<008e7846$0$9756$c3e8da3@news.astraweb.com>
	<a46c8c91-a45d-43fe-aa16-f6e4df2201bb@d4g2000yqa.googlegroups.com>
Message-ID: <1AD26B34-17FA-4315-8A4F-B3F3D09F7D29@masklinn.net>

On 31 Jul 2009, at 11:54 , Iain King wrote:
> On Jul 31, 8:28 am, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>> On Thu, 30 Jul 2009 18:06:31 -0500, Robert Kern wrote:
>>> On 2009-07-30 16:44, r wrote:
>>>> On Jul 30, 4:29 pm, Emmanuel Surleau<emmanuel.surl... at gmail.com>  
>>>> wrote:
>>>>>> 1.) No need to use "()" to call a function with no arguments.  
>>>>>> Python
>>>>>> -->  "obj.m2().m3()" --ugly
>>>>>>    Ruby -->  "obj.m1.m2.m3"  -- sweeet!
>>>>>> Man, i must admit i really like this, and your code will look  
>>>>>> so much
>>>>>> cleaner.
>>>>> It has benefits - code does look better. It has also significant  
>>>>> cons
>>>>> - it is ambiguous.
>>>>> For instance:
>>
>>>>> a = b
>>
>>>>> Is b a variable or a method called without parameter?
>>
>>>> Hello Emanuel,
>>>> Again, who so ever names a method with such a non-descriptive  
>>>> name will
>>>> get whats coming to him. And if you did for some reason use such a
>>>> cryptic name as "b", do yourself (and everyone else) a favor and  
>>>> follow
>>>> it with "()" to denote the method call. Remember when something is
>>>> optional that means you have an option to use it OR not use it.
>>
>>> I believe his point is that it is ambiguous to the compiler, not  
>>> humans
>>> reading the code. Python functions and methods are first class  
>>> objects.
>>> They can be passed around. If they were auto-called, then you  
>>> could not
>>> do this.
>>
>> Oh my, "r" is still around is he??? And now he's singing the  
>> praises of
>> Ruby, the language which he treated as the Devil's Spawn when he  
>> first
>> arrived. That's hilarious.
>>
>> But back on topic... "r" has missed the point. It's not that a=b is  
>> hard
>> to understand because b is a poor name. The example could have been:
>>
>> def factory_function():
>>     magic = time.time()  # or whatever
>>     def inner():
>>         return magic
>>     return inner
>>
>> my_function = factory_function
>>
>> It's still ambiguous. Does the programmer intend my_function to  
>> become
>> factory_function itself, or the output of factory_function?
>
> Not only that - does 'return inner' return the function inner or the
> result of function inner?
>
> How does ruby pass a function as an object?
Ruby doesn't have functions as such. It has methods and blocks (which  
would be anonymous functions). `def` always creates methods.

To get a (bound) method object, you simply call `method` on an  
instance e.g. `foo.method(:bar)` is equivalent to `foo.bar` in Python  
(it returns a bound method object without calling it).

Blocks are usually created as part of the calls: `foo.bar  
{do_something}` the part between braces (braces included) is a block,  
which will be passed to the method `bar`. Sadly, Ruby's blocks are  
magical syntax (doesn't mean they have to be, in Smalltalk there's  
nothing magical about blocks for instance) so you can't just do `foo =  
{do_something}`, you have to turn them into `Proc` objects with the  
`proc` constructor (or `lambda`, it's equivalent and looks better so  
I'll use that): `foo = lambda {do_something}`. If you use the magical  
syntax previously shown, Ruby handles the turning of a block into an  
actual `Proc` instance.

And since Ruby doesn't have a `()` operator, it uses a method instead  
(`#call`), so you simply do `foo.call` to execute the proc and get its  
value.

All in all, much like Smalltalk, Ruby tends not to favor raw functions  
the way Python does, so a direct translation of the Python code  
doesn't make much sense.


From python at mrabarnett.plus.com  Fri Jul 31 06:34:29 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 11:34:29 +0100
Subject: Processes not exiting
In-Reply-To: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
References: <6cfb2f39-c6d6-4d2a-882c-18f21addf206@a13g2000yqc.googlegroups.com>
Message-ID: <4A72C8B5.1030309@mrabarnett.plus.com>

ma3mju wrote:
> Hi all,
> 
> I'm having trouble with multiprocessing I'm using it to speed up some
> simulations, I find for large queues when the process reaches the
> poison pill it does not exit whereas for smaller queues it works
> without any problems. Has anyone else had this trouble? Can anyone
> tell me a way around it? The code is in two files below.
> 
[snip]
> 
> #get number of cores and set the number on concurrent processes
> num_hard_workers = 2
> num_workers = multiprocessing.cpu_count()*1.5
> easy_workers = []
> hard_workers = []
> #add poison pill for each worker and create the worker
> for i in range(0,num_workers-num_hard_workers):
>     easy_work_queue.put(None)
>     easy_workers.append(multiprocessing.Process
> (target=GP.RandomWalkGeneralizationErrorParallel,args=
> (easy_work_queue,result_queue,)))
> for i in range(0,num_hard_workers):
>     hard_work_queue.put(None)
>     hard_workers.append(multiprocessing.Process
> (target=GP.RandomWalkGeneralizationErrorParallel,args=
> (hard_work_queue,result_queue,)))
> 
You have 2 hard workers and ceil(CPU_count * 1.5) - 2 easy workers.
What if the number of CPUs was 1? That would give 2 hard and 0 easy!

Also, I recommend that you put only 1 'poison pill' in each queue and
have the workers put it back when they see it.



From hendrik at microcorp.co.za  Fri Jul 31 06:47:30 2009
From: hendrik at microcorp.co.za (Hendrik van Rooyen)
Date: Fri, 31 Jul 2009 12:47:30 +0200
Subject: file comparison
In-Reply-To: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <200907311247.30793.hendrik@microcorp.co.za>

On Friday 31 July 2009 11:25:17 learner learner wrote:
> Hi all,
>
> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a third
> file or overwrite into one of them.

This is not as simple as it seems.

You will probably be better off using diff, or,
if it is a learning exercise, studying its source.

- Hendrik



From deets at nospam.web.de  Fri Jul 31 07:26:06 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 31 Jul 2009 13:26:06 +0200
Subject: problem on socket programming
In-Reply-To: <67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
Message-ID: <4A72D4CE.6030501@nospam.web.de>

MalC0de schrieb:
> On Jul 31, 12:07 pm, Chris Rebert <c... at rebertia.com> wrote:
>> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
>>> now I've been encountered to some errors with this snippet :
>> And these errors are? Provide error messages and full tracebacks.
>>
>> Cheers,
>> Chris
>> --http://blog.rebertia.com
> 
> these are errors :
> 
> Traceback (most recent call last):
>   File "echo-client.py", line 11, in <module
>     sockobj.connect((serverHost,serverPort))
>   File "<string>", line 1, in connect
> socket.error: (10061, 'Connection refused')

Can you ping and telnet to the port on the desired server? Firewalls can 
be an issue here.

Diez


From deets at nospam.web.de  Fri Jul 31 07:26:41 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 31 Jul 2009 13:26:41 +0200
Subject: problem on socket programming
In-Reply-To: <67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
Message-ID: <7dg2niF2bue0tU2@mid.uni-berlin.de>

MalC0de schrieb:
> On Jul 31, 12:07 pm, Chris Rebert <c... at rebertia.com> wrote:
>> On Fri, Jul 31, 2009 at 1:02 AM, MalC0de<malc0de.encr... at gmail.com> wrote:
>>> now I've been encountered to some errors with this snippet :
>> And these errors are? Provide error messages and full tracebacks.
>>
>> Cheers,
>> Chris
>> --http://blog.rebertia.com
> 
> these are errors :
> 
> Traceback (most recent call last):
>   File "echo-client.py", line 11, in <module
>     sockobj.connect((serverHost,serverPort))
>   File "<string>", line 1, in connect
> socket.error: (10061, 'Connection refused')

Can you ping and telnet to the port on the desired server? Firewalls can 
be an issue here.

Diez


From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 31 07:38:56 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 31 Jul 2009 13:38:56 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <008e82e8$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <4a72d7cf$0$25239$426a34cc@news.free.fr>

Steven D'Aprano a ?crit :
> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
> 
>> That and the fact that I couldn't stop laughing for long enough to learn
>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>> unlike less flexible languages, lets you alter the value of a constant."
>> Yep, as they say "Bug" = "Undocumented feature"!
> 
> That's no different from Python's "constant by convention".

Well, at least Python doesn't pretend to have real symbolic constants - 
we all know it's only a convention !-)

> We don't even 
> get a compiler warning!

Of course - from the compiler's POV, it's only usual rebinding.

> On the other hand, we don't have to prefix names with @ and @@,

Nope, we have to prefix them with 'self' or 'cls' (or even 
'self.__class__').

> and we 
> don't have the compiler trying to *guess* whether we're calling a 
> function or referring to a variable.

Please re-read a bit more carefully - it's *all* method call. Python is 
'uniform' in obj.name is always an attribute lookup (methods being 
attributes), Ruby is uniform in that 'obj.name' is always a method call.

> Somebody who knows more Ruby than me should try writing the Zen of Ruby. 
> Something like:

(snip childish parody of Python Zen)

Steven, is that any useful ?

> 
> Although I'm sure Ruby has its good points. I'm not convinced anonymous 
> code blocks are one of them though.

Ruby's code blocks come from Smalltalk, where they are an absolute 
necessity since message passing (which code blocks are part of) is the 
*only* builtin control flow in Smalltalk - so you just *need* this 
construction to provide branching and iterations.

Wether it makes sense to have code blocks in Ruby is another question 
since Ruby does provide traditional control flow features, but then one 
could question Python's "lambda" (hem...) too.


From j.sundo at cs.ucl.ac.uk  Fri Jul 31 07:41:49 2009
From: j.sundo at cs.ucl.ac.uk (=?ISO-8859-1?Q?Jannik_Sund=F8?=)
Date: Fri, 31 Jul 2009 12:41:49 +0100
Subject: Confused About Python Loggin
In-Reply-To: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>
References: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>
Message-ID: <14CCA71D-F575-4B8A-8C99-67BDAAC2C6E0@cs.ucl.ac.uk>

Hi all. I think I fixed this problem by setting fileLogger.propagate =  
0. Otherwise it will propagate up to the root logger, which outputs to  
stdout, as far as I can understand.


On 31 Jul 2009, at 01:17, Jannik Sund? wrote:

> Dear all, I am quite confused about the Python logging. I have read  
> and re-read the Python documentation for the Python logging module  
> and googled, but to no avail. I simply want one logger to log to a  
> file and another logger to log to the console. Neither should log  
> the other's messages. The code below causes fileLogger to log to  
> BOTH a file and the console, how come? It seems to me that a call  
> such as "consoleHandler = logging.StreamHandler()" affects other  
> loggers, which I do not want. Also, if I do not do  
> logging.basicConfig(level=logging.INFO) in one of the classes of my  
> application, the logging does not work. Any ideas how come?
>
> Thanks a lot for any help! :)
>
> fileHandler = logging.FileHandler('../../logs/log.txt')
> fileLogger = logging.getLogger('TESTHARNESSFILE')
> fileLogger.addHandler(fileHandler)
> fileLogger.setLevel(logging.INFO)
> consoleHandler = logging.StreamHandler()
> logger = logging.getLogger('TESTHARNESS')
> logger.addHandler(consoleHandler)
> logger.setLevel(logging.INFO)



From malc0de.encrypt at gmail.com  Fri Jul 31 07:49:09 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 04:49:09 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
Message-ID: <5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>


you want to say shall i  disable the firewall, there's no specific
firewall or IPS/IDS system out there, this is just windows xp firewall


From deets at nospam.web.de  Fri Jul 31 08:08:25 2009
From: deets at nospam.web.de (Diez B. Roggisch)
Date: Fri, 31 Jul 2009 14:08:25 +0200
Subject: problem on socket programming
In-Reply-To: <5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
Message-ID: <7dg55pF2bfubpU1@mid.uni-berlin.de>

MalC0de schrieb:
> you want to say shall i  disable the firewall, there's no specific
> firewall or IPS/IDS system out there, this is just windows xp firewall

Which is a firewall, don't you agree? So it could well be the reason for 
the problems you see.

Diez


From masklinn at masklinn.net  Fri Jul 31 08:18:56 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 14:18:56 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a72d7cf$0$25239$426a34cc@news.free.fr>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
Message-ID: <23AB2CC9-71D1-4498-8D23-D3648C00DD4C@masklinn.net>

On 31 Jul 2009, at 13:38 , Bruno Desthuilliers wrote:
> Steven D'Aprano a ?crit :
>> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>> That and the fact that I couldn't stop laughing for long enough to  
>>> learn
>>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>>> unlike less flexible languages, lets you alter the value of a  
>>> constant."
>>> Yep, as they say "Bug" = "Undocumented feature"!
>> That's no different from Python's "constant by convention".
> Ruby's code blocks come from Smalltalk, where they are an absolute  
> necessity since message passing (which code blocks are part of) is  
> the *only* builtin control flow in Smalltalk - so you just *need*  
> this construction to provide branching and iterations.
>
I'm not so sure about the way you say it. I'm pretty sure  
"traditional" flow control structures preceded Smalltalk by a pair of  
decades so it's not that Smalltalk's designers found it necessary to  
use blocks & messages, but that they understood blocks & messages  
could trivially replace most control structures (making *those*  
unnecessary), making the core language simpler and more flexible.

In other words, I see it the other way around.

> Wether it makes sense to have code blocks in Ruby is another  
> question since Ruby does provide traditional control flow features
Well it does at least allow for the creation of new flow control  
structures in library land when the existing ones aren't enough (e.g.  
allows Ruby not to require the introduction of a `with` statement).  
Though Ruby's blocks are nowhere near as flexible as Smalltalk's.

From vinay_sajip at yahoo.co.uk  Fri Jul 31 08:24:58 2009
From: vinay_sajip at yahoo.co.uk (Vinay Sajip)
Date: Fri, 31 Jul 2009 05:24:58 -0700 (PDT)
Subject: Confused About Python Loggin
References: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk> 
	<mailman.4040.1249040521.8015.python-list@python.org>
Message-ID: <21effe68-2202-4f58-a2d9-f1ea3968149a@d32g2000yqh.googlegroups.com>

On Jul 31, 12:41?pm, Jannik Sund? <j.su... at cs.ucl.ac.uk> wrote:
> Hi all. I think I fixed this problem by setting fileLogger.propagate = ?
> 0. Otherwise it will propagate up to the root logger, which outputs to ?
> stdout, as far as I can understand.
>

Only if you specifically configure it to do so - for example, calling
basicConfig() configures the root logger (if it has no handlers) by
adding a StreamHandler which outputs to sys.stderr.

You shouldn't need to set propagate - the script in Peter's reply
appears to do what you need.

Regards,

Vinay Sajip


From malc0de.encrypt at gmail.com  Fri Jul 31 08:37:21 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 05:37:21 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
	<7dg55pF2bfubpU1@mid.uni-berlin.de>
Message-ID: <f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>

no, I disabled my firewall, no problem with even enabled firewall ...
no one can help !?


From davea at ieee.org  Fri Jul 31 08:55:27 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 31 Jul 2009 08:55:27 -0400
Subject: file comparison
In-Reply-To: <200907311247.30793.hendrik@microcorp.co.za>
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
	<200907311247.30793.hendrik@microcorp.co.za>
Message-ID: <4A72E9BF.3080808@ieee.org>

Hendrik van Rooyen wrote:
> On Friday 31 July 2009 11:25:17 learner learner wrote:
>   
>> Hi all,
>>
>> I want to compare two text files line by line and eliminate the
>> matching/repeated line and store the unmatched/leftout lines into a third
>> file or overwrite into one of them.
>>     
>
> This is not as simple as it seems.
>
> You will probably be better off using diff, or,
> if it is a learning exercise, studying its source.
>
> - Hendrik
>
>
>   

It is not only "not simple," it's totally underspecified.


Learner:

If this is a homework assignment, you should read the whole assignment, 
and see what it says.  Without knowing something about the text files, I 
couldn't even guess what the real goal is.

For example, if the text files are really text (e.g. a letter to 
grandma), then we want a context-sensitive comparison, the kind that 
Windiff, RCSDiff, DiffMerge, and others can do.

If the text files are each a list of items, with order and duplication 
irrelevant, then your best bet is probably to build a set from each, and 
difference the sets.

DaveA


From jeanmichel at sequans.com  Fri Jul 31 09:04:59 2009
From: jeanmichel at sequans.com (Jean-Michel Pichavant)
Date: Fri, 31 Jul 2009 15:04:59 +0200
Subject: Confused About Python Loggin
In-Reply-To: <14CCA71D-F575-4B8A-8C99-67BDAAC2C6E0@cs.ucl.ac.uk>
References: <534A6695-37D9-4200-9872-9E844AE50681@cs.ucl.ac.uk>
	<14CCA71D-F575-4B8A-8C99-67BDAAC2C6E0@cs.ucl.ac.uk>
Message-ID: <4A72EBFB.4080306@sequans.com>

Jannik Sund? wrote:
> Hi all. I think I fixed this problem by setting fileLogger.propagate = 
> 0. Otherwise it will propagate up to the root logger, which outputs to 
> stdout, as far as I can understand.
>
>
> On 31 Jul 2009, at 01:17, Jannik Sund? wrote:
>
>> Dear all, I am quite confused about the Python logging. I have read 
>> and re-read the Python documentation for the Python logging module 
>> and googled, but to no avail. I simply want one logger to log to a 
>> file and another logger to log to the console. Neither should log the 
>> other's messages. The code below causes fileLogger to log to BOTH a 
>> file and the console, how come? It seems to me that a call such as 
>> "consoleHandler = logging.StreamHandler()" affects other loggers, 
>> which I do not want. Also, if I do not do 
>> logging.basicConfig(level=logging.INFO) in one of the classes of my 
>> application, the logging does not work. Any ideas how come?
>>
>> Thanks a lot for any help! :)
>>
>> fileHandler = logging.FileHandler('../../logs/log.txt')
>> fileLogger = logging.getLogger('TESTHARNESSFILE')
>> fileLogger.addHandler(fileHandler)
>> fileLogger.setLevel(logging.INFO)
>> consoleHandler = logging.StreamHandler()
>> logger = logging.getLogger('TESTHARNESS')
>> logger.addHandler(consoleHandler)
>> logger.setLevel(logging.INFO)
>
> --http://mail.python.org/mailman/listinfo/python-list
>
Please do not top post :o)

Are sure you have used the code provided above ?
Loggers only propagate events to its parent.

fileLogger = logging.getLogger('TESTHARNESSFILE"
logger = logging.getLogger('TESTHARNESS')
Those one have no parent relationship.

However these one have parent relationship:
fileLogger = logging.getLogger('TESTHARNESS.FILE") # note the dotted name
logger = logging.getLogger('TESTHARNESS')


Or maybe you have added a handler to the root logger...

Using the propagate attribute is correct only between 2 loggers that are 
meant to be parents.

JM


From python at mrabarnett.plus.com  Fri Jul 31 09:05:35 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 14:05:35 +0100
Subject: problem on socket programming
In-Reply-To: <f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com>
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com>
	<mailman.4020.1249027664.8015.python-list@python.org>	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>	<7dg2niF2bue0tU2@mid.uni-berlin.de>	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>	<7dg55pF2bfubpU1@mid.uni-berlin.de>
	<f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
Message-ID: <4A72EC1F.7040709@mrabarnett.plus.com>

MalC0de wrote:
> no, I disabled my firewall, no problem with even enabled firewall ...
> no one can help !?

I hope you disconnected your computer from the internet before disabling
the firewall...



From bruno.42.desthuilliers at websiteburo.invalid  Fri Jul 31 09:12:42 2009
From: bruno.42.desthuilliers at websiteburo.invalid (Bruno Desthuilliers)
Date: Fri, 31 Jul 2009 15:12:42 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <mailman.4041.1249042752.8015.python-list@python.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>	<008e82e8$0$9756$c3e8da3@news.astraweb.com>	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<mailman.4041.1249042752.8015.python-list@python.org>
Message-ID: <4a72edca$0$32755$426a74cc@news.free.fr>

Masklinn a ?crit :
> On 31 Jul 2009, at 13:38 , Bruno Desthuilliers wrote:
>> Steven D'Aprano a ?crit :
>>> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>>> That and the fact that I couldn't stop laughing for long enough to 
>>>> learn
>>>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>>>> unlike less flexible languages, lets you alter the value of a 
>>>> constant."
>>>> Yep, as they say "Bug" = "Undocumented feature"!
>>> That's no different from Python's "constant by convention".
>> Ruby's code blocks come from Smalltalk, where they are an absolute 
>> necessity since message passing (which code blocks are part of) is the 
>> *only* builtin control flow in Smalltalk - so you just *need* this 
>> construction to provide branching and iterations.
>>
> I'm not so sure about the way you say it.

I'm not sure about the way you understand it !-)

> I'm pretty sure "traditional" 
> flow control structures preceded Smalltalk by a pair of decades

Yes, of course - and that's not the point. What's important is that:


> so it's 
> not that Smalltalk's designers found it necessary to use blocks & 
> messages, but that they understood blocks & messages could trivially 
> replace most control structures (making *those* unnecessary), making the 
> core language simpler and more flexible.

Exactly.

> In other words, I see it the other way around.

My wording may have been a bit confusing, indeed. It was implied (but 
perhaps a bit unclear) that restricting control structures to messages 
and blocks was a design choice.

>> Wether it makes sense to have code blocks in Ruby is another question 
>> since Ruby does provide traditional control flow features
 >
> Well it does at least allow for the creation of new flow control 
> structures in library land when the existing ones aren't enough (e.g. 
> allows Ruby not to require the introduction of a `with` statement). 

Yeps. But then other "traditionnal" control flow features become redundant.

> Though Ruby's blocks are nowhere near as flexible as Smalltalk's.


From processor.dev1l at gmail.com  Fri Jul 31 09:15:00 2009
From: processor.dev1l at gmail.com (Processor-Dev1l)
Date: Fri, 31 Jul 2009 06:15:00 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
	<7dg55pF2bfubpU1@mid.uni-berlin.de>
	<f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
Message-ID: <72f851f9-a2d4-4448-900d-3fe20e4ebeb0@w41g2000yqb.googlegroups.com>

On Jul 31, 2:37?pm, MalC0de <malc0de.encr... at gmail.com> wrote:
> no, I disabled my firewall, no problem with even enabled firewall ...
> no one can help !?

Connection refused... connection was refused by the listening socket,
it could also be due to the settings of your service, if it accepts
only from localhost to localhost (127.0.0.1 to 127.0.0.1) then other
connections will not be granted. Try to find some socket samples on
python.org (there are plenty of tip and tricks for using sockets)


From processor.dev1l at gmail.com  Fri Jul 31 09:21:14 2009
From: processor.dev1l at gmail.com (Processor-Dev1l)
Date: Fri, 31 Jul 2009 06:21:14 -0700 (PDT)
Subject: Run pyc file without specifying python path ?
References: <mailman.44.1248861603.12188.python-list@python.org> 
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C4@enbmail01.lsi.com> 
	<4A708F68.1010505@ieee.org>
	<7F0503CD69378F49BE0DC30661C6CCF6701A26C7@enbmail01.lsi.com> 
	<4A7199FF.8010202@dejaviewphoto.com>
	<mailman.4030.1249031631.8015.python-list@python.org>
Message-ID: <52bdb49f-935f-459c-bc64-76e5ccb16f36@k6g2000yqn.googlegroups.com>

On Jul 30, 4:47?pm, "Barak, Ron" <Ron.Ba... at lsi.com> wrote:
> > -----Original Message-----
> > From: Dave Angel [mailto:da... at dejaviewphoto.com]
> > Sent: Thursday, July 30, 2009 16:03
> > To: Barak, Ron
> > Cc: 'Dave Angel'; 'python-l... at python.org'
> > Subject: RE: Run pyc file without specifying python path ?
>
> > Barak, Ron wrote:
> > >> -----Original Message-----
> > >> From: Dave Angel [mailto:da... at ieee.org]
> > >> Sent: Wednesday, July 29, 2009 21:05
> > >> To: Barak, Ron
> > >> Cc: 'python-l... at python.org'
> > >> Subject: Re: Run pyc file without specifying python path ?
>
> > >> Barak, Ron wrote:
>
> > >>> Hi,
>
> > >>> I wanted to make a python byte-code file executable,
>
> > >> expecting to be able to run it without specifying "python" on the
> > >> (Linux bash) command line.
>
> > >>> So, I wrote the following:
>
> > >>> [root at VMLinux1 python]# cat test_pyc.py #!/usr/bin/env python
>
> > >>> print "hello"
> > >>> [root at VMLinux1 python]#
>
> > >>> and made its pyc file executable:
>
> > >>> [root at VMLinux1 python]# ls -ls test_pyc.pyc
> > >>> 4 -rwxr-xr-x ?1 root root 106 Jul 29 14:22 test_pyc.pyc
> > >>> [root at VMLinux1 python]#
>
> > >>> So, I see:
>
> > >>> [root at VMLinux1 python]# file test_pyc.py*
> > >>> test_pyc.py: ?a python script text executable
> > >>> test_pyc.pyc: python 2.3 byte-compiled
> > >>> [root at VMLinux1 python]#
>
> > >>> If I try to do the following, no problem:
>
> > >>> [root at VMLinux1 python]# python test_pyc.pyc hello
> > >>> [root at VMLinux1 python]#
>
> > >>> However, the following fails:
>
> > >>> [root at VMLinux1 python]# ./test_pyc.pyc
> > >>> -bash: ./test_pyc.pyc: cannot execute binary file
> > >>> [root at VMLinux1 python]#
>
> > >>> Is there a way to run a pyc file without specifying the
>
> > >> python path ?
>
> > >>> Bye,
> > >>> Ron.
>
> > >> I don't currently run Unix, but I think I know the problem.
>
> > >> In a text file, the shell examines the first line, and if
> > it begins
> > >> #!
> > >> it's assumed to point to the executable of an interpreter for that
> > >> text file. ?Presumably the same trick doesn't work for a .pyc file.
>
> > >> Why not write a trivial wrapper.py file, don't compile it, and let
> > >> that invoke the main code in the .pyc file?
>
> > >> Then make wrapper.py executable, and you're ready to go.
>
> > >> DaveA
>
> > > Hi Dave,
> > > Your solution sort of defeats my intended purpose (sorry
> > for not divulging my 'hidden agenda').
> > > I wanted my application to "hide" the fact that it's a
> > python script, and look as much as possible like it's a
> > compiled program.
> > > The reason I don't just give my user a py file, is that I
> > don't want a cleaver user to change the innards of the script.
> > > On the other hand, I don't want to make a compiled
> > (freezed?) version of the application, because it'll grow the
> > resulting file significantly, and I don't have the experience
> > to know how it will run on different Linuxes.
> > > Bye,
> > > Ron.
>
> Hi Dave,
>
> > Most of the other answers basically paraphrased my suggestion
> > of making a wrapper file, not compiling it, and making it
> > executable. ?With that
> > approach, the user just types ? "wrapper.py" on his command line.
>
> > And wrapper.py only needs two lines, a shebang, and an
> > import, no big deal if the user modifies it. ?The rest of
> > your code can be .pyc files.
>
> > Steven makes some good points. ?You have to define what level
> > of clever you're protecting from. ?A determined hacker will
>
> The clever I try to guard against is not at hacker level, just the curios worker.
>
> > get in no matter what you do, unless you want to ship the
> > program in a proprietary embedded system, encased in epoxy. ?
> > Further, if you have an extension of .py or .pyc, a
> > knowledgeable hacker will know it's probably python.
>
> Granted, but the user will know that from the user manual anyway :-)
>
>
>
> > You imply you want it to run unmodifed on multiple unknown
> > Linux versions. ?I think that lets out binfmt solutions. ?
>
> Actually, no: I know the set of Linuxes my users are likely to have.
>
> > That means you need to test and support not only multiple
> > Linux implementations, but multiple Python versions, because
> > who knows what the user may have installed. ?I think you need
> > to rethink your support strategy. ?And maybe concentrate on
> > being able to detect change, rather than prevent it.
>
> > DaveA
>
> Thanks for the helpful suggestions.
> Ron.

how can a compiled python file (pyc) can defend your code against
clever-user? Try command cat "yourcode.pyc" and you will is how
"hardly" it can be read or modified :).
The most easy way how to distribute such file is with some shell batch
containing
#!/usr/bin/sh
python ./lib/myscript.pyc

the topology of the app would be a shell script called simply run, or
name of your app and something like that and a folder called lib where
your pyc file is stored, just make the script executable (chmod a+x
shellfile or chmod 755 shellfile) and force ppl to use it instead of
the pyc file in the lib folder :)


From masklinn at masklinn.net  Fri Jul 31 09:39:47 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 15:39:47 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <4a72edca$0$32755$426a74cc@news.free.fr>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>	<008e82e8$0$9756$c3e8da3@news.astraweb.com>	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<mailman.4041.1249042752.8015.python-list@python.org>
	<4a72edca$0$32755$426a74cc@news.free.fr>
Message-ID: <CBC838D8-3977-4DA4-8CBF-506F2E9A3B8E@masklinn.net>

On 31 Jul 2009, at 15:12 , Bruno Desthuilliers wrote:
> Masklinn a ?crit :
>> On 31 Jul 2009, at 13:38 , Bruno Desthuilliers wrote:
>>> Steven D'Aprano a ?crit :
>>>> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>>>> That and the fact that I couldn't stop laughing for long enough  
>>>>> to learn
>>>>> any more when I read in the Pragmatic Programmer's Guide that  
>>>>> "Ruby,
>>>>> unlike less flexible languages, lets you alter the value of a  
>>>>> constant."
>>>>> Yep, as they say "Bug" = "Undocumented feature"!
>>>> That's no different from Python's "constant by convention".
>>> Ruby's code blocks come from Smalltalk, where they are an absolute  
>>> necessity since message passing (which code blocks are part of) is  
>>> the *only* builtin control flow in Smalltalk - so you just *need*  
>>> this construction to provide branching and iterations.
>
[misunderstandings on my part/clarifications on yours]
>> Well it does at least allow for the creation of new flow control  
>> structures in library land when the existing ones aren't enough  
>> (e.g. allows Ruby not to require the introduction of a `with`  
>> statement).
>
> Yeps. But then other "traditionnal" control flow features become  
> redundant.
They can be anyway: Ruby doesn't deprecate most control flows as the  
actual usages of blocks are a bit restricted (cannot be used for  
`while` as it would require the serialization to a Proc, and Ruby's  
syntax doesn't allow sending multiple blocks to a method so `if?else`  
is out as well). And I assume they reintroduced the for?in sugar to  
ease the transition from more traditional languages (using #each and  
others seems the suggested collection iterators across the community).

From malc0de.encrypt at gmail.com  Fri Jul 31 09:43:49 2009
From: malc0de.encrypt at gmail.com (MalC0de)
Date: Fri, 31 Jul 2009 06:43:49 -0700 (PDT)
Subject: problem on socket programming
References: <fc9826c6-25e8-4b83-9b69-07ab21067a5a@32g2000yqj.googlegroups.com>
	<3de0863c-15ef-4153-8d0f-6b7a438b98f5@c2g2000yqi.googlegroups.com> 
	<e09b9e08-dbe4-4704-94fd-d83b29804a7d@j32g2000yqh.googlegroups.com> 
	<mailman.4020.1249027664.8015.python-list@python.org>
	<67ec3e6d-0995-459a-a7a5-3bc296729664@b15g2000yqd.googlegroups.com>
	<7dg2niF2bue0tU2@mid.uni-berlin.de>
	<5dbf451d-a289-40d1-83db-ce655d47f698@r38g2000yqn.googlegroups.com>
	<7dg55pF2bfubpU1@mid.uni-berlin.de>
	<f1cd891b-b937-428b-be2c-40d156faa70f@32g2000yqj.googlegroups.com>
	<72f851f9-a2d4-4448-900d-3fe20e4ebeb0@w41g2000yqb.googlegroups.com>
Message-ID: <c3afedd5-fb5b-43f3-99e9-fee23f8564d8@w41g2000yqb.googlegroups.com>

none of you can't interpret it ? do you have errors like me !?


From gary.wilson at gmail.com  Fri Jul 31 09:51:05 2009
From: gary.wilson at gmail.com (Gary Wilson)
Date: Fri, 31 Jul 2009 06:51:05 -0700 (PDT)
Subject: supported versions policy?
Message-ID: <07526890-6264-43c0-bd01-29ffdb3eedc2@d9g2000prh.googlegroups.com>

Does Python have a formal policy on the support lifetime (bug fixes,
security fixes, etc.) for major and minor versions?  I did a bit of
searching on the Python web site and this group, but didn't find
anything.  If there is a policy posted somewhere (and I just didn't
dig deep enough), would someone please point me in the right
direction.  If there is no posted policy, would someone be kind enough
to describe the practiced policy here.

I'm looking for is something like this:
http://docs.djangoproject.com/en/dev/internals/release-process/#supported-versions

Thanks,
Gary


From Scott.Daniels at Acm.Org  Fri Jul 31 09:51:17 2009
From: Scott.Daniels at Acm.Org (Scott David Daniels)
Date: Fri, 31 Jul 2009 06:51:17 -0700
Subject: fast video encoding
In-Reply-To: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
References: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
Message-ID: <i8OdncfuALBtae_XnZ2dnUVZ_uSdnZ2d@pdx.net>

gregorth wrote:
> for a scientific application I need to save a video stream to disc for
> further post processing. My cam can deliver 8bit grayscale images with
> resolution 640x480 with a framerate up to 100Hz, this is a data rate
> of 30MB/s. Writing the data uncompressed to disc hits the data
> transfer limits of my current system and creates huge files. Therefore
> I would like to use video compression, preferably fast and high
> quality to lossless encoding. Final file size is not that important.
Well, it sounds like it better be enough to affect bandwidth.

> I am a novice with video encoding. I found that few codecs support
> gray scale images. Any hints to take advantage of the fact that I only
> have gray scale images?

You might try to see if there is a primitive .MNG encoder around.
That could give you lossless with perhaps enough compression to make
you happy, and I'm sure it will handle the grayscale.

.MNG is pictures only, but that doesn't hurt you in the least.

--Scott David Daniels
Scott.Daniels at Acm.Org


From roger.miller at nova-sol.com  Fri Jul 31 10:22:56 2009
From: roger.miller at nova-sol.com (Roger Miller)
Date: Fri, 31 Jul 2009 07:22:56 -0700 (PDT)
Subject: Test for Pythonwin?
References: <4a728aac$0$9744$5a62ac22@per-qv1-newsreader-01.iinet.net.au>
Message-ID: <7be1b318-851d-4197-afd4-48de38c878e6@d34g2000vbm.googlegroups.com>

On Jul 31, 2:09?am, "steve" <st... at nospam.au> wrote:
> Is there a good way to check if a script is running inside Pythonwin?
> Perhaps a property or method that is exposed by that environment?

I've used
  if sys.stdin.fileno() < 0:
This is not precisely a test for pythonwin, but indicates whether
standard streams are available, which is usually what I really
want to know.


From ethan at stoneleaf.us  Fri Jul 31 11:08:29 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 31 Jul 2009 08:08:29 -0700
Subject: Confessions of a Python fanboy
In-Reply-To: <008e82e8$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <4A7308ED.7040108@stoneleaf.us>

Steven D'Aprano wrote:
> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
> 
> 
>>That and the fact that I couldn't stop laughing for long enough to learn
>>any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>>unlike less flexible languages, lets you alter the value of a constant."
>>Yep, as they say "Bug" = "Undocumented feature"!
> 
> 
> That's no different from Python's "constant by convention". We don't even 
> get a compiler warning!
> 

That's quite different, actually.  Python doesn't claim to have 
constants!  Can't misinterpret what you can't have, can you?

[Holds breath while awaiting counter-example... :]

~Ethan~


From ethan at stoneleaf.us  Fri Jul 31 11:15:14 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 31 Jul 2009 08:15:14 -0700
Subject: Regexp problem
In-Reply-To: <4A72135E.7060205@mrabarnett.plus.com>
References: <aea7d655-d946-45b0-9266-2c44cef286b8@26g2000yqk.googlegroups.com>	<mailman.3961.1248959276.8015.python-list@python.org>	<30761c97-aeb0-474d-8047-c7fa38c04a86@w41g2000yqb.googlegroups.com>	<h4s7pm$rgr$1@adenine.netfront.net>	<4A720AD5.1030202@stoneleaf.us>
	<4A72135E.7060205@mrabarnett.plus.com>
Message-ID: <4A730A82.3050502@stoneleaf.us>

MRAB wrote:
> Ethan Furman wrote:
> 
>> Marcus Wanner wrote:
>>> Wow, I really need to learn more about regexp...
>>> Any tutorials you guys can recommend?
>>>
>>> Marcus
>>
>>
>> Mastering Regular Expressions
>> Powerful Techniques for Perl and Other Tools
>> By Jeffrey E. F. Friedl
>>
>> Great book!
>>
> +1
> 
> I have the first edition, seventh printing (December 1998). It refers to
> the 'regex' module of Python 1.4b1, which was subsequently replaced by
> the current 're' module and then removed from the standard library. I
> hope it's been updated since then. :-)

I have the second edition (no idea which printing ;), and according to 
his preface it has indeed been much updated.  Most examples are in perl, 
the few in python are decent.  The knowledge embodied seems very 
thorough.  Since I've had the book (two weeks now?)  I've been able to 
solve two otherwise thorny issues using regular expressions.  Yay!

~Ethan~


From iainking at gmail.com  Fri Jul 31 11:35:45 2009
From: iainking at gmail.com (Iain King)
Date: Fri, 31 Jul 2009 08:35:45 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com> 
	<mailman.4048.1249052760.8015.python-list@python.org>
Message-ID: <c30eb377-49e0-4c1c-b9be-151704626b9d@b14g2000yqd.googlegroups.com>

On Jul 31, 4:08?pm, Ethan Furman <et... at stoneleaf.us> wrote:
> Steven D'Aprano wrote:
> > On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>
> >>That and the fact that I couldn't stop laughing for long enough to learn
> >>any more when I read in the Pragmatic Programmer's Guide that "Ruby,
> >>unlike less flexible languages, lets you alter the value of a constant."
> >>Yep, as they say "Bug" = "Undocumented feature"!
>
> > That's no different from Python's "constant by convention". We don't even
> > get a compiler warning!
>
> That's quite different, actually. ?Python doesn't claim to have
> constants! ?Can't misinterpret what you can't have, can you?
>
> [Holds breath while awaiting counter-example... :]
>
> ~Ethan~

The convention being detailed in PEP8: http://www.python.org/dev/peps/pep-0008/
basically, anything in ALL_CAPS is a constant, assuming you follow
those style guidelines.

Iain


From benjamin.kaplan at case.edu  Fri Jul 31 11:52:37 2009
From: benjamin.kaplan at case.edu (Benjamin Kaplan)
Date: Fri, 31 Jul 2009 11:52:37 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <c30eb377-49e0-4c1c-b9be-151704626b9d@b14g2000yqd.googlegroups.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<mailman.4048.1249052760.8015.python-list@python.org>
	<c30eb377-49e0-4c1c-b9be-151704626b9d@b14g2000yqd.googlegroups.com>
Message-ID: <ec96e1390907310852u4b905e1dld764d6579528cc23@mail.gmail.com>

On Fri, Jul 31, 2009 at 11:35 AM, Iain King<iainking at gmail.com> wrote:
> On Jul 31, 4:08?pm, Ethan Furman <et... at stoneleaf.us> wrote:
>> Steven D'Aprano wrote:
>> > On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>>
>> >>That and the fact that I couldn't stop laughing for long enough to learn
>> >>any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>> >>unlike less flexible languages, lets you alter the value of a constant."
>> >>Yep, as they say "Bug" = "Undocumented feature"!
>>
>> > That's no different from Python's "constant by convention". We don't even
>> > get a compiler warning!
>>
>> That's quite different, actually. ?Python doesn't claim to have
>> constants! ?Can't misinterpret what you can't have, can you?
>>
>> [Holds breath while awaiting counter-example... :]
>>
>> ~Ethan~
>
> The convention being detailed in PEP8: http://www.python.org/dev/peps/pep-0008/
> basically, anything in ALL_CAPS is a constant, assuming you follow
> those style guidelines.
>

Right, but that's a style guide and not a language definition. Nobody
claims that anything in there is a part of the language.

> Iain
> --
> http://mail.python.org/mailman/listinfo/python-list
>


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 11:55:43 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 15:55:43 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
Message-ID: <008eef29$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 13:38:56 +0200, Bruno Desthuilliers wrote:

>> On the other hand, we don't have to prefix names with @ and @@,
> 
> Nope, we have to prefix them with 'self' or 'cls' (or even
> 'self.__class__').

Incorrect.

>>> class K:
...     class_attribute = 'No @@ required.'
...
>>> K().class_attribute
'No @@ required.'


No 'self' or 'cls' in sight.


I can see a vague advantage to using @ to create instance attributes and 
@@ to creating class attributes -- it makes it easy to create class 
attributes inside a method without needing to do a double lookup. In 
Python terms:

def K:
    def method(self):
        self.__class__.attr = "Class attribute"

would be:

def K:
    def method(self):
        @@attr = "Class attribute"

Advantages: you save a few characters and (possibly!) a couple of runtime 
lookups.

Disadvantages: your code is filled with line noise. It's an arbitrary 
choice between @@ meaning instance attribute and @@ meaning class 
attribute -- there's no logical reason for choosing one over the other, 
so you have to memorise which is which. It's easy to get it wrong.

'self' and 'cls' at least are words, even if 'cls' is badly misspelled :)



>> and we
>> don't have the compiler trying to *guess* whether we're calling a
>> function or referring to a variable.
> 
> Please re-read a bit more carefully - it's *all* method call. 

What did I misread from here?

[quote]
When Ruby sees a name such as ``a'' in an expression, it needs to 
determine if it is a local variable reference or a call to a method with 
no parameters. To decide which is the case, Ruby uses a heuristic. As 
Ruby reads a source file, it keeps track of symbols that have been 
assigned to. It assumes that these symbols are variables. When it 
subsequently comes across a symbol that might be either a variable or a 
method call, it checks to see if it has seen a prior assignment to that 
symbol. If so, it treats the symbol as a variable; otherwise it treats it 
as a method call.
[end quote]

And see the example "pathological case" comparing a function call (not 
method) and a variable.

http://ruby-doc.org/docs/ProgrammingRuby/html/language.html


> Python is
> 'uniform' in obj.name is always an attribute lookup (methods being
> attributes), Ruby is uniform in that 'obj.name' is always a method call.

Which would be relevant if I was talking about method calls, but I wasn't.



>> Somebody who knows more Ruby than me should try writing the Zen of
>> Ruby. Something like:
> 
> (snip childish parody of Python Zen)
> 
> Steven, is that any useful ?

It made me feel good.

But seriously, while I admit that I have very little Ruby experience, and 
so aren't in a great position to judge, it seems to me that Ruby doesn't 
have anything like Python's over-riding design principles (the Zen). If 
there is a design principle to Ruby, I can't see what it is.

I'm the first to admit that I'm far too inexperienced with the language 
to make this a fair judgement. Unfair it might be, but it doesn't 
necessarily mean I'm wrong! *wink*

Ruby just seems to be far more complicated than Python: things which 
Python does at runtime, with a function call, Ruby has special syntax for:

"a bunch of words".split()
%w(a bunch of words)

ord('a')
?a

That makes the barrier to entry far higher: it's easier to leverage 
existing knowledge to interpret unfamiliar Python code than unfamiliar 
Ruby code. Or so it seems to me.

Oh, and I admit that Python decorators are a conspicuous counter-example. 
I wouldn't do without them, but neither would I expect somebody to intuit 
what they do.


>> Although I'm sure Ruby has its good points. I'm not convinced anonymous
>> code blocks are one of them though.
> 
> Ruby's code blocks come from Smalltalk, where they are an absolute
> necessity since message passing (which code blocks are part of) is the
> *only* builtin control flow in Smalltalk - so you just *need* this
> construction to provide branching and iterations.

Just because Smalltalk had a particular (mis?)feature doesn't mean that 
other languages should copy it. I know, I know, Ruby people swear by 
anonymous code blocks, and I've read Paul Graham too. But I'm really not 
so sure that the benefits of anonymous code blocks are great enough to 
overcome the disadvantages of anonymous code blocks.


> Wether it makes sense to have code blocks in Ruby is another question
> since Ruby does provide traditional control flow features, but then one
> could question Python's "lambda" (hem...) too.

lambda, by allowing the function to be only a single expression, doesn't 
suffer the disadvantages of anonymous code blocks. lambda, by allowing 
the function to be only a single expression, also has fewer advantages 
than anonymous code blocks. I think lambda ends up on the "more 
advantages than disadvantages" side. I'm keeping my mind open regarding 
Ruby code blocks.



-- 
Steven


From masklinn at masklinn.net  Fri Jul 31 12:15:15 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 18:15:15 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <008eef29$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<008eef29$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <11938EF7-4FC3-4F1A-A665-D9360442456F@masklinn.net>

On 31 Jul 2009, at 17:55 , Steven D'Aprano wrote:
> But seriously, while I admit that I have very little Ruby  
> experience, and
> so aren't in a great position to judge, it seems to me that Ruby  
> doesn't
> have anything like Python's over-riding design principles (the Zen).  
> If
> there is a design principle to Ruby, I can't see what it is.
>
As far as I know, Ruby doesn't have anything like the Zen no. But then  
again, I don't know any language other than Python with such a document.

> Ruby just seems to be far more complicated than Python: things which
> Python does at runtime, with a function call, Ruby has special  
> syntax for:
>
> "a bunch of words".split()
> %w(a bunch of words)
>
> ord('a')
> ?a
>
That's the Perl heritage. And since it inherits from Perl, TIMTOWTDI:
     >> "a bunch of words".split
     => ["a", "bunch", "of", "words"]
     >> "a"[0]
     => 97
(yes, the indexing operator returns a character code if provided a  
single index. With two, it returns as string slice)

Oh and %w() isn't really equivalent to split(): you don't use it to  
split a string but to create a list of strings, so the equivalent  
expression in Python would be `["a", "bunch", "of", "words"]`.

> That makes the barrier to entry far higher: it's easier to leverage
> existing knowledge to interpret unfamiliar Python code than unfamiliar
> Ruby code. Or so it seems to me.
>
That's probable.

>>> Although I'm sure Ruby has its good points. I'm not convinced  
>>> anonymous
>>> code blocks are one of them though.
>>
>> Ruby's code blocks come from Smalltalk, where they are an absolute
>> necessity since message passing (which code blocks are part of) is  
>> the
>> *only* builtin control flow in Smalltalk - so you just *need* this
>> construction to provide branching and iterations.
>
> Just because Smalltalk had a particular (mis?)feature doesn't mean  
> that
> other languages should copy it. I know, I know, Ruby people swear by
> anonymous code blocks, and I've read Paul Graham too. But I'm really  
> not
> so sure that the benefits of anonymous code blocks are great enough to
> overcome the disadvantages of anonymous code blocks.
>
What are the disadvantages of anonymous functions?



From tjreedy at udel.edu  Fri Jul 31 12:24:28 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 12:24:28 -0400
Subject: Confessions of a Python fanboy
In-Reply-To: <FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
Message-ID: <h4v5rr$hrn$1@ger.gmane.org>

Masklinn wrote:

> #each is simply a method that takes a function (called blocks in ruby). 
> One could call it a higher-order method I guess.
> 
> It's an implementation of the concept of internal iteration: instead of 
> collections yielding iterator objects, and programmers using those 
> through specially-built iteration constructs (e.g. `for?in`), 
> collections control iteration over themselves (the iteration is 
> performed "inside" the collection, thus the "internal" part) and the 
> programmer provides the operations to perform at each iterative step 
> through (usually) a function.

Python's iterator protocol was developed in part to avoid the 
(inside-out) callback style of programming. Writing virtual collections 
as generator functions instead of iterator or iterable classes saves a 
lot of boilerplate code. The itertools modules shows how nicely 
iterators can be composed in a way that is much more awkward with callbacks.

> In Python (assuming we had anonymous defs and an each method on lists), 
> the following loop:
> 
>     for item in some_list:
>         do_something(item)
>         do_something_else(item)
> 
>     some_list.each((def (item):
>         do_something(item)
>         do_something_else(item)
>     ))

And how does Ruby do the equivalent of

def double(it):
   for i in it:
     yield 2*i

for i,j in zip(double(some_list), some_gen_func(args)):
   print(do_something(i+j,i-j))

Terry Jan Reedy



From bdezonia at wisc.edu  Fri Jul 31 12:33:45 2009
From: bdezonia at wisc.edu (BDZ)
Date: Fri, 31 Jul 2009 09:33:45 -0700 (PDT)
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
	<3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>
Message-ID: <337482f9-8ad9-4600-9cf4-39911f5368ac@h31g2000yqd.googlegroups.com>

On Jul 30, 4:41?pm, Lo?c Domaign? <loic.domai... at googlemail.com>
wrote:
> Hi,
>
> > Hello. I have written a Python 3.1 script running on Windows that uses
> > os.path.exists() to connect to network shares. If the various network
> > shares require different user account and password combos than the
> > account the script is running under the routine returns false. I need
> > something like os.samba.path.exists(username,password,path). Does
> > anyone have a suggestion on how I can accomplish what I need to do in
> > Python?
>
> Could the Python Samba module PySamba be interesting for you?http://sourceforge.net/projects/pysamba/
>
> HTH,
> Lo?c
> --
> My blog:http://www.domaigne.com/blog

Unfortunately, although it has the calls I'd want, pysamba appears to
be *nix only. I need something that will work under Windows. Is there
a set of Python Windows functions (official or contributed) that might
do what I need? (I'm new to Python)


From darkneter at gmail.com  Fri Jul 31 12:35:10 2009
From: darkneter at gmail.com (NighterNet)
Date: Fri, 31 Jul 2009 09:35:10 -0700 (PDT)
Subject: threads check socket
Message-ID: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>

I been trying to find a way to check the socket is open or not. The
thread are in a group and loop if the sockets are open. If they are
not open delete the thread and remove the group. I need on this.


From tjreedy at udel.edu  Fri Jul 31 12:39:21 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 12:39:21 -0400
Subject: supported versions policy?
In-Reply-To: <07526890-6264-43c0-bd01-29ffdb3eedc2@d9g2000prh.googlegroups.com>
References: <07526890-6264-43c0-bd01-29ffdb3eedc2@d9g2000prh.googlegroups.com>
Message-ID: <h4v6no$kd6$1@ger.gmane.org>

Gary Wilson wrote:
> Does Python have a formal policy on the support lifetime (bug fixes,
> security fixes, etc.) for major and minor versions?  I did a bit of
> searching on the Python web site and this group, but didn't find
> anything.  If there is a policy posted somewhere (and I just didn't
> dig deep enough), would someone please point me in the right
> direction.  If there is no posted policy, would someone be kind enough
> to describe the practiced policy here.

Defining Pyx.y.z as Pymajor.minor.bugfix, the last normal bugfix comes 
out about the same time as the next minor. True security fixes (very 
rare) come out for a couple of years thereafter. (Exception, 3.0 support 
ended with 3.0.1 -- it should be replaced with 3.1.) Currently Py2 and 
Py3 are running in parallel. The future 2.7.z's will probably be the end 
of the Py2 series. Everything is contingent on voluteer time to do the 
above.

tjr



From db3l.net at gmail.com  Fri Jul 31 12:40:34 2009
From: db3l.net at gmail.com (David Bolen)
Date: Fri, 31 Jul 2009 12:40:34 -0400
Subject: fast video encoding
References: <570097d0-2b2a-4705-892f-0d0154d69d63@b14g2000yqd.googlegroups.com>
Message-ID: <m2y6q43iwt.fsf@valheru.db3l.homeip.net>

gregorth <gregor.thalhammer at gmail.com> writes:

> I am a novice with video encoding. I found that few codecs support
> gray scale images. Any hints to take advantage of the fact that I only
> have gray scale images?

I don't know that there's any good way around the fact that video
encoding is simply one of the heavier CPU-bound activities you're
likely to encounter.  So I suspect that codec choice (barring letting
quality drop a bit) is going to move the bar less than picking the
beefiest CPU you can.

If I were looking to do this, I'd probably include investigating
pumping the raw camera images into an ffmpeg encoding subprocess and
let it handle all the encoding.  There's about a gazillion options and
a variety of codec options to play with for performance.  You could
grab and store a short video sample from the camera and use it as a
benchmark to compare encoding options.

ffmpeg does have a -pix_fmt option that can be used to indicate the
input pixel type - "gray" would be 8-bit, and result in a 4:0:0 image
with a YUV-based encoder, for example.  Not sure how much, if any,
impact it would have on encoding speed though.

To be honest, with your data rate, I might even consider getting
Python out of the pure encoding path once it starts - depending on the
raw network format delivered by the camera you might be able to have
ffmpeg read directly from it.  Might not be worth it, since the data
transfer is probably I/O bound, but a 640x480x1 stream at 100Hz is
still nothing to sniff at, and even managing the raw data flow in
Python might eat up some CPU that you could better allocate to the
encoding process, or require extra data copies along the way that
would be best to avoid.

-- David


From garrickp at gmail.com  Fri Jul 31 12:53:44 2009
From: garrickp at gmail.com (Falcolas)
Date: Fri, 31 Jul 2009 09:53:44 -0700 (PDT)
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>
	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net> 
	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net> 
	<2d56febf0907310121g36bb6e54yae84cb82a22b58e7@mail.gmail.com> 
	<50697b2c0907310125r5eebbdcewfec4ff2337c53140@mail.gmail.com> 
	<mailman.4036.1249033777.8015.python-list@python.org>
Message-ID: <5028a8b0-21b6-4052-8483-7236b9142bd9@h21g2000yqa.googlegroups.com>

On Jul 31, 3:49?am, Masklinn <maskl... at masklinn.net> wrote:
> On 31 Jul 2009, at 10:25 , Chris Rebert wrote:> On Fri, Jul 31, 2009 at 1:21 AM, Xavier Ho<cont... at xavierho.com> ?
> > wrote:
> >> On Fri, Jul 31, 2009 at 6:08 PM, Masklinn <maskl... at masklinn.net> ?
> >> wrote:
>
> >>> <snip>... but since Python doesn't have anonymous functions that ?
> >>> usage
> >>> tends to be a bit too verbose ... <snip>
>
> >> Sorry to interrupt, but wouldn't lambda in Python be considered as
> >> 'anonymous functions'?
>
> > I believe "full" anonymous functions was intended by the author.
> > lambdas are limited to a single expression.
>
> Yes, and they're limited to a single *expression*, so before Python 3, ?
> lambda: print "foo" is out. Likewise, it isn't possible to have an if/
> else statement within a lambda (though a ternary is ok), or a with, ? ?
> since Python statements aren't expressions.

Perhaps you can't do lambda foo: print foo, but you *can* do lambda x:
sys.stdout.write(x).

Combined with the ternary if, it seem sufficient if you want to stick
to the ideal "Simple is better than Complex". Sure, with statements
allowed in anonymous functions, you can save on a line of typing (def
blargh(x):), but I don't feel the obfuscation is worth the cost.

~G


From digitig at gmail.com  Fri Jul 31 12:54:23 2009
From: digitig at gmail.com (Tim Rowe)
Date: Fri, 31 Jul 2009 17:54:23 +0100
Subject: Confessions of a Python fanboy
In-Reply-To: <008e82e8$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>

2009/7/31 Steven D'Aprano <steve at remove-this-cybersource.com.au>:
> On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
>
>> That and the fact that I couldn't stop laughing for long enough to learn
>> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
>> unlike less flexible languages, lets you alter the value of a constant."
>> Yep, as they say "Bug" = "Undocumented feature"!
>
> That's no different from Python's "constant by convention". We don't even
> get a compiler warning!

We don't actually *declare* that something is constant and then have
that declaration ignored. Python doesn't lie to us, although (as in
any language) a programmer might.

-- 
Tim Rowe


From jabronson at gmail.com  Fri Jul 31 13:02:55 2009
From: jabronson at gmail.com (Joshua Bronson)
Date: Fri, 31 Jul 2009 10:02:55 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<86skgr0yjn.fsf@gmail.com>
	<pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au> 
	<Xns9C5082EB1B123duncanbooth@127.0.0.1>
Message-ID: <ec98fc01-4a2e-4c7b-9155-9e37e1b91151@g25g2000vbr.googlegroups.com>

On Jul 22, 7:55?am, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> I find it interesting that the heapq functions tell you in the
> documentation that they aren't suitable for use where n==1 or where n is
> near the total size of the sequence whereas random.sample() chooses what it
> thinks is the best algorithm based on the input. At the very least I would
> have thought the heapq functions could check for n==1 and call min/max when
> it is.

I've had the same thought myself a number of times, so I filed a bug:
http://bugs.python.org/issue6614


From marcusw at cox.net  Fri Jul 31 13:22:24 2009
From: marcusw at cox.net (Marcus Wanner)
Date: Fri, 31 Jul 2009 13:22:24 -0400
Subject: threads check socket
In-Reply-To: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
Message-ID: <h4v98g$25dt$1@adenine.netfront.net>

On 7/31/2009 12:35 PM, NighterNet wrote:
> I been trying to find a way to check the socket is open or not. The
> thread are in a group and loop if the sockets are open. If they are
> not open delete the thread and remove the group. I need on this.
Being a bit more specific would help.

Are you using tcp or udp? Is it a local socket or a remote one? What is 
controlling the socket? Define "open".

Marcus


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 13:23:02 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 14:23:02 -0300
Subject: threads check socket
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
Message-ID: <op.uxxzworex6zn5v@gabriel.sleipnir-bsas>

En Fri, 31 Jul 2009 13:35:10 -0300, NighterNet <darkneter at gmail.com>  
escribi?:

> I been trying to find a way to check the socket is open or not. The
> thread are in a group and loop if the sockets are open. If they are
> not open delete the thread and remove the group. I need on this.

What means an "open socket"? Do you want to detect whether the other side  
closed the connection? In that case reading from the socket returns an  
empty string.

Regarding the "threads in a group", I don't understand what you mean. But  
in general, you don't delete a thread, you just return from its run()  
method and the thread finishes execution.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 13:32:13 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 14:32:13 -0300
Subject: file comparison
References: <29a34bc20907310225n50b35fe2m322872af2058a465@mail.gmail.com>
Message-ID: <op.uxx0bzg2x6zn5v@gabriel.sleipnir-bsas>

En Fri, 31 Jul 2009 06:25:17 -0300, learner learner <pyvault2.6 at gmail.com>  
escribi?:

> I want to compare two text files line by line and eliminate the
> matching/repeated line and store the unmatched/leftout lines into a third
> file or overwrite into one of them.

Look at the difflib module: http://docs.python.org/library/difflib.html

If that's not what you want, you have to provide much more details.

-- 
Gabriel Genellina



From python at rcn.com  Fri Jul 31 13:32:46 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 10:32:46 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<86skgr0yjn.fsf@gmail.com>
	<pan.2009.07.22.06.40.15@REMOVE.THIS.cybersource.com.au> 
	<Xns9C5082EB1B123duncanbooth@127.0.0.1>
Message-ID: <b8857b9d-fbd6-48b3-b33b-d824829368fc@k13g2000prh.googlegroups.com>

On Jul 22, 4:55?am, Duncan Booth <duncan.bo... at invalid.invalid> wrote:
> Steven D'Aprano <ste... at REMOVE.THIS.cybersource.com.au> wrote:
> > But that's the wrong solution to the problem. The OP wants the largest
> > (or smallest) item, which he expects to get by sorting, then grabbing
> > the first element:
>
> > sorted(alist)[0]
>
> > That requires sorting the entire list, only to throw away everything
> > except the first item. A better solution is to use min() and max(),
> > neither of which sort the list, so they are much faster.
>
> And if they want the n smallest or largest items (where n is significantly
> less than the length of the list[*]) they might consider using
> heapq.nsmallest() and heapq.nlargest()
>
> I find it interesting that the heapq functions tell you in the
> documentation that they aren't suitable for use where n==1 or where n is
> near the total size of the sequence whereas random.sample() chooses what it
> thinks is the best algorithm based on the input. At the very least I would
> have thought the heapq functions could check for n==1 and call min/max when
> it is.

The heapq.py code in Py2.7 and Py3.1 already does some automatic
algorithm selection:
http://svn.python.org/view/python/branches/release31-maint/Lib/heapq.py?revision=73579&view=markup

The automatic seletion of alternatives only occurs in clear-cut cases
(such as n==1
or where n==len(iterable) when the iterable has a known length).   For
the
remaining cases, the switchover point from heapq to sorted needs a
programmer's judgment based on whether the input iterable has a known
length, the cost of comparison function, and whether input is already
partially ordered.

The advice in the docs helps the reader understand the
relationships between min, max, nsmallest, nlargest, and sorted.


Raymond


From ethan at stoneleaf.us  Fri Jul 31 13:41:15 2009
From: ethan at stoneleaf.us (Ethan Furman)
Date: Fri, 31 Jul 2009 10:41:15 -0700
Subject: .dbf tables and Null
Message-ID: <4A732CBB.9090400@stoneleaf.us>

Mornin'!  and a good one, too, I hope.

Question for you...

First part of the question:  What is the general value in having Null 
capability for fields?

Second part:  Is there a tangible difference between Null, and the 
nothing of 0, '', False, etc, in python?

Third part:  If there is a tangible difference, do those of us who use 
python and these old, refuse-to-die, .dbf files actually have need of, 
or have tables including, Null values?

P.S. part (for John Machin, if he sees this  ;)
Will the dbf package you are working on support Null values?

Any and all information appreciated!

~Ethan~


From darkneter at gmail.com  Fri Jul 31 13:42:29 2009
From: darkneter at gmail.com (NighterNet)
Date: Fri, 31 Jul 2009 10:42:29 -0700 (PDT)
Subject: threads check socket
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
	<mailman.4055.1249061007.8015.python-list@python.org>
Message-ID: <7b3247b0-4c85-4290-9de2-41fc45348d3d@z4g2000prh.googlegroups.com>

On Jul 31, 10:23?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Fri, 31 Jul 2009 13:35:10 -0300, NighterNet <darkne... at gmail.com> ?
> escribi?:
>
> > I been trying to find a way to check the socket is open or not. The
> > thread are in a group and loop if the sockets are open. If they are
> > not open delete the thread and remove the group. I need on this.
>
> What means an "open socket"? Do you want to detect whether the other side ?
> closed the connection? In that case reading from the socket returns an ?
> empty string.
>
> Regarding the "threads in a group", I don't understand what you mean. But ?
> in general, you don't delete a thread, you just return from its run() ?
> method and the thread finishes execution.
>
> --
> Gabriel Genellina

Thread added into the array. Well this thread when user leave the
server want to make sure it not in used so that I can reuse it some
how or move into another array.

Need to know the thread speed that need for game server timer to
control it. Don't want it too fast or slow for the game server.
fps = 30
	def run(self):
		while True:
			self.gametime += 1
			if self.gametime > 10000000/fps:
				self.gametime = 0;


From jabronson at gmail.com  Fri Jul 31 13:44:33 2009
From: jabronson at gmail.com (Joshua Bronson)
Date: Fri, 31 Jul 2009 10:44:33 -0700 (PDT)
Subject: heapq "key" arguments
Message-ID: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>

According to http://docs.python.org/library/heapq.html, Python 2.5
added an optional "key" argument to heapq.nsmallest and
heapq.nlargest. I could never understand why they didn't also add a
"key" argument to the other relevant functions (heapify, heappush,
etc). Say I want to maintain a heap of (x, y) pairs sorted only by
first coordinate. Without being able to pass key=itemgetter(0), won't
heapifying a list of such pairs unnecessarily compare both
coordinates? And worse, if the second coordinate is actually an object
with no ordering defined for it, heapifying will cause an error even
though all I care about is sorting by the first coordinate, which does
have an ordering. Am I missing something?


From python at rcn.com  Fri Jul 31 13:49:04 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 10:49:04 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
Message-ID: <86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>

On Jul 20, 9:27?am, Phillip B Oldham <phillip.old... at gmail.com> wrote:
> Specifically the "differences" between lists and tuples have us
> confused and have caused many "discussions" in the office. We
> understand that lists are mutable and tuples are not, but we're a
> little lost as to why the two were kept separate from the start. They
> both perform a very similar job as far as we can tell.

The underlying C code for the two is substantially the same.  In terms
of code, tuples are in effect just immutable lists that have the
added
feature of being hashable (and therefore usable as dictionary keys or
elements of sets).

Beyond the mutable/hashable distinction, there is an important
philosophical distinction articulated by Guido.  He deems tuples
to be useful for struct like groupings of non-homogenous fields
and lists to be useful for sequences of homogenous data suitable
for looping.

While nothing in the list/tuple code requires you to make that
distinction,
it is important because that philosophy pervades the language.  If you
follow Guido's direction, you'll find that the various parts of the
language fit together better.  Do otherwise and you'll be going
against
the grain.


Raymond

P.S.  The C code for lists and tuples have a slightly difference
internal
structure that makes tuples a little more space efficient (since their
size is known at the outset and doesn't change during use).


From jgardner at jonathangardner.net  Fri Jul 31 14:02:48 2009
From: jgardner at jonathangardner.net (Jonathan Gardner)
Date: Fri, 31 Jul 2009 11:02:48 -0700 (PDT)
Subject: heapq "key" arguments
References: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>
Message-ID: <1582f82e-34aa-4b66-b989-c9f8351a5f1c@o9g2000prg.googlegroups.com>

On Jul 31, 10:44?am, Joshua Bronson <jabron... at gmail.com> wrote:
> Say I want to maintain a heap of (x, y) pairs sorted only by
> first coordinate. Without being able to pass key=itemgetter(0), won't
> heapifying a list of such pairs unnecessarily compare both
> coordinates?

It will compare the second value only if the first values are equal.


From bfrederi at library.unt.edu  Fri Jul 31 14:08:44 2009
From: bfrederi at library.unt.edu (Brandon Fredericks)
Date: Fri, 31 Jul 2009 11:08:44 -0700 (PDT)
Subject: base64 Incorrect Padding
Message-ID: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>

I did a search within this group, but couldn't find any information on
this.

I am sending base64 encoded data as the content over http using
urllib2 urlopen. When I receive the data and attempt to decode it, I
get an "Incorrect Padding" error. Is there a simple way to fix this? A
better way to send and receive the data possibly (using base64 of
course)?


From masklinn at masklinn.net  Fri Jul 31 14:15:09 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 20:15:09 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <h4v5rr$hrn$1@ger.gmane.org>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>	<op.uxwdlizifvx12t@jerzozwiesz.home.aster.pl>	<293A960D-EFB7-4A09-917A-7ECD3D769B46@masklinn.net>	<200907301757.48761.kyrie@uh.cu>
	<FA96809F-86F5-43E7-B565-998EBA32198F@masklinn.net>
	<h4v5rr$hrn$1@ger.gmane.org>
Message-ID: <003A7A2F-0FF1-42D4-96ED-1EBBA605B475@masklinn.net>

On 31 Jul 2009, at 18:24 , Terry Reedy wrote:
> Masklinn wrote:
>
>> #each is simply a method that takes a function (called blocks in  
>> ruby). One could call it a higher-order method I guess.
>> It's an implementation of the concept of internal iteration:  
>> instead of collections yielding iterator objects, and programmers  
>> using those through specially-built iteration constructs (e.g. `for? 
>> in`), collections control iteration over themselves (the iteration  
>> is performed "inside" the collection, thus the "internal" part) and  
>> the programmer provides the operations to perform at each iterative  
>> step through (usually) a function.
>
> Python's iterator protocol was developed in part to avoid the  
> (inside-out) callback style of programming. Writing virtual  
> collections as generator functions instead of iterator or iterable  
> classes saves a lot of boilerplate code. The itertools modules shows  
> how nicely iterators can be composed in a way that is much more  
> awkward with callbacks.
>
>> In Python (assuming we had anonymous defs and an each method on  
>> lists), the following loop:
>>    for item in some_list:
>>        do_something(item)
>>        do_something_else(item)
>>    some_list.each((def (item):
>>        do_something(item)
>>        do_something_else(item)
>>    ))
>
> And how does Ruby do the equivalent of
>
> def double(it):
>  for i in it:
>    yield 2*i
>
> for i,j in zip(double(some_list), some_gen_func(args)):
>  print(do_something(i+j,i-j))


Somethign along the lines of

     some_list.map{|e| 2*e}.zip(some_gen_func(args)).each {|i, j|
         puts(do_something(i+j, i-j))
     }

The `#each` call after `#zip` is not actually necessary, but I find it  
clearer. Oh, and some_gen_func and do_something probably wouldn't work  
that way (as I said above, Ruby isn't big on named functions and  
doesn't actually have them)

From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 14:17:05 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 31 Jul 2009 18:17:05 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<008eef29$0$9756$c3e8da3@news.astraweb.com>
	<mailman.4051.1249056929.8015.python-list@python.org>
Message-ID: <008f104b$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 18:15:15 +0200, Masklinn wrote:

> > I know, I know, Ruby people swear by
> > anonymous code blocks, and I've read Paul Graham too. But I'm really
> > not so sure that the benefits of anonymous code blocks are great
> > enough to overcome the disadvantages of anonymous code blocks.
> >
> What are the disadvantages of anonymous functions?

In no particular order, and not necessarily exhaustive:

* The risk of obfuscation in your code. That's fairly minimal for 
lambdas, because they're just a single expression, but for a large 
anonymous code block (ACB) defined inside a named function, it may be 
difficult for the reader to easily distinguish which bits are the outer 
function and which are the ACB.


* Loss of useful debugging information. Take this example from Python:

>>> def main(f):
...     return f(3)
...
>>> main(lambda n: 2/(n-3))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in main
  File "<stdin>", line 1, in <lambda>
ZeroDivisionError: integer division or modulo by zero
>>>
>>> def my_special_function(n):
...     return 2/(n-3)
...
>>> main(my_special_function)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in main
  File "<stdin>", line 2, in my_special_function
ZeroDivisionError: integer division or modulo by zero

If your code has only one anonymous function (whether a lambda or a full 
multi-line block), then it's easy to identify which lambda raised the 
exception: there is only one it could be. But if your code uses lots of 
lambdas, the lack of a function name makes it hard to distinguish one 
<lambda> from another <lambda>. Anonymity makes identification harder.


* Risk of code-duplication and breaking the principle of Once And Only 
Once. Anonymous functions are generally created, used, then immediately 
thrown away -- or at least made more-or-less inaccessible for reuse. An 
anonymous function stored in a callback still exists, but the coder isn't 
able to easily re-use it for another callback somewhere else in the code. 
Consequently, there's a temptation for the coder to write the same 
function multiple times:

add_button("Parrot", colour=blue, callback=lambda x: x.stuff('a'))
add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
add_button("Canary", colour=yellow, callback=lambda x: x.stuff('a'))

instead of:

def bird_callback(x):
    return x.stuff('a')

add_button("Parrot", colour=blue, callback=bird_callback)
add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
add_button("Canary", colour=yellow, callback=bird_callback)

* Recursion is more or less impossible without fragile tricks.

(At least for Python. I don't know how recursion operates in Ruby.)





-- 
Steven


From dciphercomputing at gmail.com  Fri Jul 31 14:22:26 2009
From: dciphercomputing at gmail.com (Simon)
Date: Fri, 31 Jul 2009 11:22:26 -0700 (PDT)
Subject: Newbie Question regarding __init__()
Message-ID: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>

Hi

I want to create an instance of dcCursor which inherits from
dcObject.  When I run the following code it gives the error shown.
Can some explain to me what is wrong? I have included the dcObject.py
and dcCursor.py below.

>>>import dcObject
>>> import dcCursor
>>> x = dcCursor.dcCursor()
Traceback (most recent call last):
  File "<interactive input>", line 1, in <module>
TypeError: __init__() takes no arguments (1 given)

# -*- coding: utf-8 -*-
# dcCursor.py - The base Cursor Class

from dcObject import dcObject

class dcCursor(dcObject):
    """The base Cursor Class"""
    def OpenCursor(tcTemp,tcTable):
        """Opens the specified cursor
        Parameters: tcTemp,tcTable"""
        pass

    def CreateCursor(tcTable):
        """Creates the specified cursor
        Parameters: tcTable"""
        pass

    def init_Exec():
        print("init_Exec called")



# -*- coding: utf-8 -*-
# dcObject.py - Base Object
class dcObject(object):
    """Base Object"""
    def __init__():
        """default init method has the form
        of init_Pre() and init_Exec
        init_Post()"""
        self.init_Pre() and self.init_Exec()
        self.init_Post()

    def init_Pre():
        """Always called before init_Exec()
        if it returns false init_Exec is
        not executed"""
        return True

    def init_Exec():
        """Base __init__ code goes here and this is
        only executed if init_Pre() returns true"""
        return True

    def init_Post():
        """Always called after the init_Pre() and
        init_Exec()"""
        return True



From nobody at nowhere.com  Fri Jul 31 14:22:33 2009
From: nobody at nowhere.com (Nobody)
Date: Fri, 31 Jul 2009 19:22:33 +0100
Subject: Printing with colors in a portable way
References: <33e19169-19b4-497a-b262-2bcf7b5637d5@r38g2000yqn.googlegroups.com>
Message-ID: <pan.2009.07.31.18.22.32.640000@nowhere.com>

On Thu, 30 Jul 2009 15:40:37 -0700, Robert Dailey wrote:

> Anyone know of a way to print text in Python 3.1 with colors in a
> portable way? In other words, I should be able to do something like
> this:
> 
> print_color( "This is my text", COLOR_BLUE )
> 
> And this should be portable (i.e. it should work on Linux, Mac,
> Windows).

The way that terminals (and emulators) handle colour is fundamentally
different from the DOS/Windows console. If you want something which will
work on both, you will have write separate implementations for terminals
and the DOS/Windows console.

For terminals, you can use the "curses" package, e.g.:

import curses

curses.setupterm()
setaf = curses.tigetstr('setaf')
setab = curses.tigetstr('setab')

def foreground(num):
    if setaf:
        sys.stdout.write(curses.tparm(setaf, num))

def background(num):
    if setab:
        sys.stdout.write(curses.tparm(setab, num))

For the Windows console, you'll need to use ctypes to interface to the
SetConsoleTextAttribute() function from Kernel32.dll.



From python at mrabarnett.plus.com  Fri Jul 31 14:33:57 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 19:33:57 +0100
Subject: Newbie Question regarding __init__()
In-Reply-To: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
Message-ID: <4A733915.9020203@mrabarnett.plus.com>

Simon wrote:
> Hi
> 
> I want to create an instance of dcCursor which inherits from
> dcObject.  When I run the following code it gives the error shown.
> Can some explain to me what is wrong? I have included the dcObject.py
> and dcCursor.py below.
> 
>>>> import dcObject
>>>> import dcCursor
>>>> x = dcCursor.dcCursor()
> Traceback (most recent call last):
>   File "<interactive input>", line 1, in <module>
> TypeError: __init__() takes no arguments (1 given)
> 
All instance methods must have the instance as the first argument, by
convention called 'self':

> # -*- coding: utf-8 -*-
> # dcCursor.py - The base Cursor Class
> 
> from dcObject import dcObject
> 
> class dcCursor(dcObject):
>     """The base Cursor Class"""
>     def OpenCursor(tcTemp,tcTable):
     def OpenCursor(self, tcTemp, tcTable):

>         """Opens the specified cursor
>         Parameters: tcTemp,tcTable"""
>         pass
> 
>     def CreateCursor(tcTable):
     def CreateCursor(self, tcTable):
...

and so on, including the '__init__' method.


From emmanuel.surleau at gmail.com  Fri Jul 31 14:41:12 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 20:41:12 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>
Message-ID: <200907312041.12241.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 18:54:23 Tim Rowe wrote:
> 2009/7/31 Steven D'Aprano <steve at remove-this-cybersource.com.au>:
> > On Thu, 30 Jul 2009 18:47:04 +0100, Tim Rowe wrote:
> >> That and the fact that I couldn't stop laughing for long enough to learn
> >> any more when I read in the Pragmatic Programmer's Guide that "Ruby,
> >> unlike less flexible languages, lets you alter the value of a constant."
> >> Yep, as they say "Bug" = "Undocumented feature"!
> >
> > That's no different from Python's "constant by convention". We don't even
> > get a compiler warning!
>
> We don't actually *declare* that something is constant and then have
> that declaration ignored. Python doesn't lie to us, although (as in
> any language) a programmer might.

You could say that Ruby doesn't either, you just need to read the 
documentation. Ruby's unwritten motto is "flexibility ?ber alles". In this 
regard, it is consistent (1). Not much is really bolted down in Ruby. You get 
encapsulation, but it's so easy to break that it's mostly symbolic. It's a 
language which gives great power to the programmer. Whether Ruby programmers 
handle this power responsibly is another debate.

Cheers,

Emm

(1) I find Ruby to be pretty consistent in general, which is not always the 
case of Python.


From emmanuel.surleau at gmail.com  Fri Jul 31 14:48:03 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 20:48:03 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
Message-ID: <200907312048.03922.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 19:49:04 Raymond Hettinger wrote:
> On Jul 20, 9:27 am, Phillip B Oldham <phillip.old... at gmail.com> wrote:
> > Specifically the "differences" between lists and tuples have us
> > confused and have caused many "discussions" in the office. We
> > understand that lists are mutable and tuples are not, but we're a
> > little lost as to why the two were kept separate from the start. They
> > both perform a very similar job as far as we can tell.
>
> The underlying C code for the two is substantially the same.  In terms
> of code, tuples are in effect just immutable lists that have the
> added
> feature of being hashable (and therefore usable as dictionary keys or
> elements of sets).
>
> Beyond the mutable/hashable distinction, there is an important
> philosophical distinction articulated by Guido.  He deems tuples
> to be useful for struct like groupings of non-homogenous fields
> and lists to be useful for sequences of homogenous data suitable
> for looping.
>
> While nothing in the list/tuple code requires you to make that
> distinction,
> it is important because that philosophy pervades the language.  If you
> follow Guido's direction, you'll find that the various parts of the
> language fit together better.  Do otherwise and you'll be going
> against
> the grain.

I might be wrong, but I get the impression that many people don't indeed "get 
it" and use tuples as static arrays and lists when the array needs to be 
dynamically resized. This is certainly how I use them as well.

This would tend to show that Guido's notion here was not particularly 
intuitive.

Cheers,

Emm


From __peter__ at web.de  Fri Jul 31 14:56:15 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 20:56:15 +0200
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
Message-ID: <h4veod$n9l$01$1@news.t-online.com>

Brandon Fredericks wrote:

> I did a search within this group, but couldn't find any information on
> this.
> 
> I am sending base64 encoded data as the content over http using
> urllib2 urlopen. When I receive the data and attempt to decode it, I
> get an "Incorrect Padding" error. Is there a simple way to fix this? A
> better way to send and receive the data possibly (using base64 of
> course)?

Have the server send some known data. Read it with urllib2.urlopen(). 
Compare with that same data that you encoded locally. What are the 
differences?

Peter




From masklinn at masklinn.net  Fri Jul 31 15:24:33 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 21:24:33 +0200
Subject: Confessions of a Python fanboy
In-Reply-To: <008f104b$0$9756$c3e8da3@news.astraweb.com>
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<mailman.3981.1248976469.8015.python-list@python.org>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<4a72d7cf$0$25239$426a34cc@news.free.fr>
	<008eef29$0$9756$c3e8da3@news.astraweb.com>
	<mailman.4051.1249056929.8015.python-list@python.org>
	<008f104b$0$9756$c3e8da3@news.astraweb.com>
Message-ID: <A07CE303-587E-400E-9BBC-267CD0C5FB0E@masklinn.net>

On 31 Jul 2009, at 20:17 , Steven D'Aprano wrote:
> On Fri, 31 Jul 2009 18:15:15 +0200, Masklinn wrote:
>
>>> I know, I know, Ruby people swear by
>>> anonymous code blocks, and I've read Paul Graham too. But I'm really
>>> not so sure that the benefits of anonymous code blocks are great
>>> enough to overcome the disadvantages of anonymous code blocks.
>>>
>> What are the disadvantages of anonymous functions?
>
> In no particular order, and not necessarily exhaustive:
>
> * The risk of obfuscation in your code. That's fairly minimal for
> lambdas, because they're just a single expression, but for a large
> anonymous code block (ACB) defined inside a named function, it may be
> difficult for the reader to easily distinguish which bits are the  
> outer
> function and which are the ACB.
>
I believe that one's unadulterated BS.

> * Loss of useful debugging information. Take this example from Python:
>
>>>> def main(f):
> ...     return f(3)
> ...
>>>> main(lambda n: 2/(n-3))
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "<stdin>", line 2, in main
>  File "<stdin>", line 1, in <lambda>
> ZeroDivisionError: integer division or modulo by zero
>>>>
>>>> def my_special_function(n):
> ...     return 2/(n-3)
> ...
>>>> main(my_special_function)
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
>  File "<stdin>", line 2, in main
>  File "<stdin>", line 2, in my_special_function
> ZeroDivisionError: integer division or modulo by zero
>
> If your code has only one anonymous function (whether a lambda or a  
> full
> multi-line block), then it's easy to identify which lambda raised the
> exception: there is only one it could be. But if your code uses lots  
> of
> lambdas, the lack of a function name makes it hard to distinguish one
> <lambda> from another <lambda>. Anonymity makes identification harder.
>
The traceback gives you the line of the anonymous function (even in  
python) so unless you have several anonymous functions on the same  
line, there's no reason why that would be much of an issue.  
Furthermore, Python doesn't provide any more information when the  
error happens out of a function (in a `for` or a `with`), so it's not  
like there's much of a difference here between Ruby's block-based  
approach and Python's statements-based approach.

> * Risk of code-duplication and breaking the principle of Once And Only
> Once. Anonymous functions are generally created, used, then  
> immediately
> thrown away -- or at least made more-or-less inaccessible for reuse.  
> An
> anonymous function stored in a callback still exists, but the coder  
> isn't
> able to easily re-use it for another callback somewhere else in the  
> code.
> Consequently, there's a temptation for the coder to write the same
> function multiple times:
>
> add_button("Parrot", colour=blue, callback=lambda x: x.stuff('a'))
> add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
> add_button("Canary", colour=yellow, callback=lambda x: x.stuff('a'))
>
> instead of:
>
> def bird_callback(x):
>    return x.stuff('a')
>
> add_button("Parrot", colour=blue, callback=bird_callback)
> add_button("Cheese", flavour=tasty, callback=lambda x: x.thing('b'))
> add_button("Canary", colour=yellow, callback=bird_callback)
>
Yes, that one I can give you though I don't think that's a big issue.  
And it's not like it's hard to extract the anonymous function into a  
named one and then use that on the third strike, so I really don't  
believe that point holds much water.

> * Recursion is more or less impossible without fragile tricks.
>
> (At least for Python. I don't know how recursion operates in Ruby.)
Code blocks are rarely if ever used recursively. If an operation is  
using anonymous functions recursively, then there's often something  
very wrong with the idea leading to that code. So I find this  
objection irrelevant.


From masklinn at masklinn.net  Fri Jul 31 15:31:21 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 21:31:21 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <200907312048.03922.emmanuel.surleau@gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
	<200907312048.03922.emmanuel.surleau@gmail.com>
Message-ID: <3F279D7F-68C2-4523-B01D-7576F3DFAF3C@masklinn.net>

On 31 Jul 2009, at 20:48 , Emmanuel Surleau wrote:
> On Friday 31 July 2009 19:49:04 Raymond Hettinger wrote:
>> On Jul 20, 9:27 am, Phillip B Oldham <phillip.old... at gmail.com>  
>> wrote:
>>> Specifically the "differences" between lists and tuples have us
>>> confused and have caused many "discussions" in the office. We
>>> understand that lists are mutable and tuples are not, but we're a
>>> little lost as to why the two were kept separate from the start.  
>>> They
>>> both perform a very similar job as far as we can tell.
>>
>> The underlying C code for the two is substantially the same.  In  
>> terms
>> of code, tuples are in effect just immutable lists that have the
>> added
>> feature of being hashable (and therefore usable as dictionary keys or
>> elements of sets).
>>
>> Beyond the mutable/hashable distinction, there is an important
>> philosophical distinction articulated by Guido.  He deems tuples
>> to be useful for struct like groupings of non-homogenous fields
>> and lists to be useful for sequences of homogenous data suitable
>> for looping.
>>
>> While nothing in the list/tuple code requires you to make that
>> distinction,
>> it is important because that philosophy pervades the language.  If  
>> you
>> follow Guido's direction, you'll find that the various parts of the
>> language fit together better.  Do otherwise and you'll be going
>> against
>> the grain.
>
> I might be wrong, but I get the impression that many people don't  
> indeed "get
> it" and use tuples as static arrays and lists when the array needs  
> to be
> dynamically resized. This is certainly how I use them as well.
>
> This would tend to show that Guido's notion here was not particularly
> intuitive.
It's intuitive if you come to Python knowing other languages with  
tuples (which are mostly functional, and in which tuples are *never*  
sequences/iterables). At the end of the day, and if Guido's intention  
truly was what Raymond says, implementing tuples as immutable sequence  
was a mistake. And the documentation is to blame as well: in it,  
tuples are clearly described as a *sequence* type, not a *structure*  
type. 


From jabronson at gmail.com  Fri Jul 31 15:38:01 2009
From: jabronson at gmail.com (Joshua Bronson)
Date: Fri, 31 Jul 2009 12:38:01 -0700 (PDT)
Subject: heapq "key" arguments
References: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>
	<1582f82e-34aa-4b66-b989-c9f8351a5f1c@o9g2000prg.googlegroups.com>
Message-ID: <4f096546-36a1-4633-9a24-1265ce0929ce@q14g2000vbi.googlegroups.com>

On Jul 31, 2:02?pm, Jonathan Gardner <jgard... at jonathangardner.net>
wrote:
> On Jul 31, 10:44?am, Joshua Bronson <jabron... at gmail.com> wrote:
>
> > Say I want to maintain a heap of (x, y) pairs sorted only by
> > first coordinate. Without being able to pass key=itemgetter(0), won't
> > heapifying a list of such pairs unnecessarily compare both
> > coordinates?
>
> It will compare the second value only if the first values are equal.

I don't see how that helps. That's not at all the same thing as being
able to pass key=itemgetter(0).


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 15:45:53 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 16:45:53 -0300
Subject: class or thread id count
References: <585e07cc-8b0e-47e4-b6f6-cde964ed8d13@d9g2000prh.googlegroups.com>
	<f0446213-638e-41de-b2e8-6c35a1f90004@c2g2000yqi.googlegroups.com>
	<68b09353-7e30-4df2-8e05-32159b03414a@f20g2000prn.googlegroups.com>
Message-ID: <op.uxwszy0ax6zn5v@lepton.softlabbsas.com.ar>

En Thu, 30 Jul 2009 17:09:36 -0300, NighterNet <darkneter at gmail.com>
escribi?:
> On Jul 30, 12:14?pm, r <rt8... at gmail.com> wrote:
>> On Jul 30, 1:13?pm, NighterNet <darkne... at gmail.com> wrote:
>>
>> > Need some help on doing some bit simple id count. It like every time
>> > it create a class orthreadthere is id++. Python 3.1
>>
>> use a class atrribute
>
> class Person():
>   count = 0
>   def __init__(self, name, info):
>       self.name = name
>       self.info = info
>       Person.count+=1
>       self.count = Person.count

Since you menctioned "thread" in the subject, note that the above isn't
thread-safe. You'll need a lock around the last two statements.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 15:46:45 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 16:46:45 -0300
Subject: Use existing IE cookie
References: <ca5e58dd-f898-4a6d-8c17-f5e9eaa3d921@p10g2000prm.googlegroups.com>
	<7ddrqsF2b5mblU1@mid.uni-berlin.de>
	<3d78acf8-594b-4e8d-b138-fa02a77d9432@x25g2000prf.googlegroups.com>
	<7ddtd3F297bafU1@mid.uni-berlin.de>
	<22afbc37-f396-404f-8639-6191d258e6be@a39g2000pre.googlegroups.com>
	<7ddvp0F2brmgrU1@mid.uni-berlin.de>
	<33b7685b-054a-442c-8e97-46a5b77f7900@z4g2000prh.googlegroups.com>
Message-ID: <op.uxwr5eyux6zn5v@lepton.softlabbsas.com.ar>

En Thu, 30 Jul 2009 13:31:33 -0300, KB <keith at nekotaku.com> escribi?:
> On Jul 30, 9:23?am, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>> KB wrote:
>>
>> > From the HTTPCookieProcessor doco, it appears that non-IE browsers
>> > have a cookie file (and example code) but from what I can tell IE uses
>> > a hidden folder. (you can set your location in IE but it appends a
>> > folder "\Temporary Internet Files" ?-
>>
>> > Not sure how to adapt this for IE.

For IE you may use the pywin32 package:

py> import win32inet
py> win32inet.InternetGetCookie("http://sldm/", None)
'__ac_name="softlab"'

Or use ctypes to call the function of the same name in wininet.dll; see
http://msdn.microsoft.com/en-us/library/aa384710(VS.85).aspx

-- 
Gabriel Genellina



From tjreedy at udel.edu  Fri Jul 31 15:55:11 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 15:55:11 -0400
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <200907312048.03922.emmanuel.surleau@gmail.com>
References: <mailman.3431.1248107247.8015.python-list@python.org>	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com>
	<200907312048.03922.emmanuel.surleau@gmail.com>
Message-ID: <h4vi6u$ms8$1@ger.gmane.org>

Emmanuel Surleau wrote:
> 
>> Beyond the mutable/hashable distinction, there is an important 
>> philosophical distinction articulated by Guido.  He deems tuples to
>> be useful for struct like groupings of non-homogenous fields and
>> lists to be useful for sequences of homogenous data suitable for
>> looping.

I think the use of the with 'homegeneous' in this context is wrong
because 1) it is ambiguous or even sometimes not the case, and 2) it
misleads. Everything is an object, so all collections are in that sense
homogeneous. If the meaning is restricted to type(ob), than a list
'mixing' ints and floats would be non-homogeneous and not 'legitimate',
but Guido does not really mean that.

The word tuple comes from relational databases as a generalization of
single, double, triple, quadruple, quintuple, sextuple, sestuple,
octuple, etc. A tuple is a data record with a fixed number of fields
with individual meaning. There is nothing about homogeneity of data type
in that definition. A triple of floats is legitimately a tuple when each
is a coordinate (the individual meanings). In other contexts, the same
triple might properly be a list (such as of heights of people
arbitrarily ordered).

>> While nothing in the list/tuple code requires you to make that 
>> distinction,

which needs to be properly articulated...

>> it is important because that philosophy pervades the language.  If
>> you follow Guido's direction, you'll find that the various parts of
>> the language fit together better.  Do otherwise and you'll be going
>>  against the grain.

Understanding the idea certainly helps understanding the design.
For instance, it explains why no tuple comprehensions.

> I might be wrong, but I get the impression that many people don't
> indeed "get it" and use tuples as static arrays and lists when the
> array needs to be dynamically resized. This is certainly how I use
> them as well.

You also *need* lists if you want to dynamically re-arrange or replace. 
If you *must not* re-arrange or edit, then a tuple will prevent that.

I would also refer back to the idea of tuple as database record.
But a list is needed to edit without copying, so lists can be used for 
writable database records.

I believe tuple(iterable) for indefinite-length iterables is somewhat 
equivalent to tuple(list(iterable)), so there is usually no point to 
constructing a  tuple that way from such an input.

For collections defined by constants, there is a real advantage to using
tuples, since tuple constants are compiled when the bytecode is 
compiled, rather than being dynamically constructed. Inside an inner 
loop, this might make enough time difference that "Practicality beats 
purity" would apply.

> This would tend to show that Guido's notion here was not particularly
>  intuitive.

The problem is that it *is* intuitive, on his part, and usually not well
explained rationally.

Terry Jan Reedy



From python at mrabarnett.plus.com  Fri Jul 31 16:03:53 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 21:03:53 +0100
Subject: base64 Incorrect Padding
In-Reply-To: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
Message-ID: <4A734E29.9080708@mrabarnett.plus.com>

Brandon Fredericks wrote:
> I did a search within this group, but couldn't find any information on
> this.
> 
> I am sending base64 encoded data as the content over http using
> urllib2 urlopen. When I receive the data and attempt to decode it, I
> get an "Incorrect Padding" error. Is there a simple way to fix this? A
> better way to send and receive the data possibly (using base64 of
> course)?

Base-64 encodes 3 bytes (echo in the range 0-255) to 4 bytes (each in a
more restricted range). The length of the output is _always_ a multiple
of 4 (ignoring whitespace); the method adds extra padding bytes (ASCII
'=') to ensure that this is the case if the length of the input isn't a
multiple of 3.

So, if decoding raises an "Incorrect Padding" error then strip out any
whitespace and append extra ASCII '=' to make its length a multiple of
3, then try decoding again. (Or you could just repeatedly add one pad
character and retry, up to 3 times.)


From no.email at please.post  Fri Jul 31 16:10:45 2009
From: no.email at please.post (kj)
Date: Fri, 31 Jul 2009 20:10:45 +0000 (UTC)
Subject: Python docs disappointing
Message-ID: <h4vj45$5hl$1@reader1.panix.com>




I'm pretty new to Python, and I like a lot overall, but I find the
documentation for Python rather poor, overall.

I'm sure that Python experts don't have this problem: they have
internalized some good ways to access the documentation, are
productive with it, and therefore have lost the ability to see why
the Python documentations is deficient for beginners.  This explains
why a suboptimal situation can persist like this: those who are
most able fix it are also the least able to perceive it.

I've heard similar complaints from other experienced programmers
who are trying out Python for the first time: poor documentation.

Here is an *entirely typical* example: on some Unix, try

% pydoc urllib

The displayed documentation mention the optional parameter "data"
in practically every function listed (a few dozen of them).  This
parameter is not documented *anywhere* on that page.  All that we
are told is that its default value is always None.

I'm sure that I can find a full description of this parameter if
I fire up Google, and search online.  In fact, more likely than
not, I'll find far more documentation than I want.  But my point
is that a programmer should not need to do this.  The full
documentation should be readily accessible directly through a few
keystrokes.

I would love to know how experienced Python programmers quickly
zero in on the Python documentation they need.

TIA!

kynn


From jstroud at mbi.ucla.edu  Fri Jul 31 16:11:49 2009
From: jstroud at mbi.ucla.edu (James Stroud)
Date: Fri, 31 Jul 2009 13:11:49 -0700
Subject: Python quirk in evaluation order
Message-ID: <h4vj65$40k$1@zinnia.noc.ucla.edu>

Python 2.5:

mbi136-176 211% python
*** Pasting of code with ">>>" or "..." has been enabled.
########################################################################
  ##                             ipython                              ##
########################################################################
py> b = 4 if True else b
py> b
4


Isn't the right side supposed to be evaluated first?


From emmanuel.surleau at gmail.com  Fri Jul 31 16:26:58 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 22:26:58 +0200
Subject: Help understanding the decisions *behind* python?
In-Reply-To: <h4vi6u$ms8$1@ger.gmane.org>
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<200907312048.03922.emmanuel.surleau@gmail.com>
	<h4vi6u$ms8$1@ger.gmane.org>
Message-ID: <200907312226.59027.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 21:55:11 Terry Reedy wrote:
> Emmanuel Surleau wrote:
> >> Beyond the mutable/hashable distinction, there is an important
> >> philosophical distinction articulated by Guido.  He deems tuples to
> >> be useful for struct like groupings of non-homogenous fields and
> >> lists to be useful for sequences of homogenous data suitable for
> >> looping.
>
> I think the use of the with 'homegeneous' in this context is wrong
> because 1) it is ambiguous or even sometimes not the case, and 2) it
> misleads. Everything is an object, so all collections are in that sense
> homogeneous. If the meaning is restricted to type(ob), than a list
> 'mixing' ints and floats would be non-homogeneous and not 'legitimate',
> but Guido does not really mean that.
>
> The word tuple comes from relational databases as a generalization of
> single, double, triple, quadruple, quintuple, sextuple, sestuple,
> octuple, etc. A tuple is a data record with a fixed number of fields
> with individual meaning. There is nothing about homogeneity of data type
> in that definition. A triple of floats is legitimately a tuple when each
> is a coordinate (the individual meanings). In other contexts, the same
> triple might properly be a list (such as of heights of people
> arbitrarily ordered).

My understanding is that, in this context, it's not so much data types which 
are heterogeneous, but the semantic meaning of the data. For instance, a tuple 
containing (first_name, last_name, address) would be a "legitimate" tuple, but 
not a tuple containing (address, address, address), which, if we follow 
Guido's philosophy, ought to be represented as a list.

Whether including the distinction in the language offers any practical benefit 
is questionable.

[snip]

> > This would tend to show that Guido's notion here was not particularly
> >  intuitive.
>
> The problem is that it *is* intuitive, on his part, and usually not well
> explained rationally.

Excellent point.

Cheers,

Emm


From robert.kern at gmail.com  Fri Jul 31 16:28:01 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 31 Jul 2009 15:28:01 -0500
Subject: Python docs disappointing
In-Reply-To: <h4vj45$5hl$1@reader1.panix.com>
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <h4vk4h$ruk$1@ger.gmane.org>

On 2009-07-31 15:10, kj wrote:

> I would love to know how experienced Python programmers quickly
> zero in on the Python documentation they need.

http://docs.python.org/library/urllib

I use Firefox's "Quick Searches" feature to make getting this URL as fast as 
possible:

   "m urllib"

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From rt8396 at gmail.com  Fri Jul 31 16:29:36 2009
From: rt8396 at gmail.com (r)
Date: Fri, 31 Jul 2009 13:29:36 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>

On Jul 31, 3:10?pm, kj <no.em... at please.post> wrote:
> I'm pretty new to Python, and I like a lot overall, but I find the
> documentation for Python rather poor, overall.
[snip]

If you mean the built-in docs i *highly agree* with you. if you mean
docs/tutorials available across the WWW i *highly disagree* with you,
and if you mean the command line "help" i also *highly disagree*, of
which python has the-best-in the-world!

I am using 2.6.2 and the help docs are a joke. trying to find even the
simplest thing (built-in functions, etc...) is like pulling teeth. I
do not look at them anymore, or do i plan to in the future. Luckily i
know python pretty well, but i can't image the horrors a new Python
Programmer must face now...

Kj, you could not be more right. Doc maintainers need to get some
feedback from Python noobies when writing this stuff. Does anybody
remember CP4E? I know Guido put a lot of effort into this project and
very much believed in this philosophy(circa 1999~2005), although it
never really went very far, i still believe in Guido's heart the CP4E
exists -- if only barley clinging to life(...maybe?)

any thoughts on this Pythonistas?


From robert.kern at gmail.com  Fri Jul 31 16:31:21 2009
From: robert.kern at gmail.com (Robert Kern)
Date: Fri, 31 Jul 2009 15:31:21 -0500
Subject: Python quirk in evaluation order
In-Reply-To: <h4vj65$40k$1@zinnia.noc.ucla.edu>
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <h4vkaq$t30$1@ger.gmane.org>

On 2009-07-31 15:11, James Stroud wrote:
> Python 2.5:
>
> mbi136-176 211% python
> *** Pasting of code with ">>>" or "..." has been enabled.
> ########################################################################
> ## ipython ##
> ########################################################################
> py> b = 4 if True else b
> py> b
> 4
>
>
> Isn't the right side supposed to be evaluated first?

The right side of the assignment or the if-else expression? The "expr1 if 
condition else expr2" expression evaluates condition, then either expr1 or expr2 
depending on the result. The other expression is unevaluated.

 >>> a
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
NameError: name 'a' is not defined
 >>> b
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
NameError: name 'b' is not defined
 >>> 5 if True else b
5
 >>> a if False else 5
5

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco



From marduk at letterboxes.org  Fri Jul 31 16:33:00 2009
From: marduk at letterboxes.org (Albert Hopkins)
Date: Fri, 31 Jul 2009 16:33:00 -0400
Subject: Python quirk in evaluation order
In-Reply-To: <h4vj65$40k$1@zinnia.noc.ucla.edu>
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <1249072381.24514.4.camel@centar>

On Fri, 2009-07-31 at 13:11 -0700, James Stroud wrote:
> Python 2.5:
> 
> mbi136-176 211% python
> *** Pasting of code with ">>>" or "..." has been enabled.
> ########################################################################
>   ##                             ipython                              ##
> ########################################################################
> py> b = 4 if True else b
> py> b
> 4
> 
> 
> Isn't the right side supposed to be evaluated first?

Yes, the right hand side of the '=', which is evaluated from LtoR.

>From the Language Reference:

        Python evaluates expressions from left to right. Notice that
        while evaluating an assignment, the right-hand side is evaluated
        before the left-hand side.

So the right-hand side of the '=' is evaluated first:

    4 if True else b

And that's evaluated from left to right:

   4

Therefore:

b = 4





From emmanuel.surleau at gmail.com  Fri Jul 31 16:34:06 2009
From: emmanuel.surleau at gmail.com (Emmanuel Surleau)
Date: Fri, 31 Jul 2009 22:34:06 +0200
Subject: Python docs disappointing
In-Reply-To: <h4vj45$5hl$1@reader1.panix.com>
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <200907312234.06374.emmanuel.surleau@gmail.com>

On Friday 31 July 2009 22:10:45 kj wrote:
> I'm pretty new to Python, and I like a lot overall, but I find the
> documentation for Python rather poor, overall.
>
> I'm sure that Python experts don't have this problem: they have
> internalized some good ways to access the documentation, are
> productive with it, and therefore have lost the ability to see why
> the Python documentations is deficient for beginners.  This explains
> why a suboptimal situation can persist like this: those who are
> most able fix it are also the least able to perceive it.
>
> I've heard similar complaints from other experienced programmers
> who are trying out Python for the first time: poor documentation.

The documentation on python.org is quite extensive. In particular, you may 
want to look at the PEPs, which offer fascinating insights for the reasoning 
behind particular features of Python.

> Here is an *entirely typical* example: on some Unix, try
>
> % pydoc urllib
>
> The displayed documentation mention the optional parameter "data"
> in practically every function listed (a few dozen of them).  This
> parameter is not documented *anywhere* on that page.  All that we
> are told is that its default value is always None.
>
> I'm sure that I can find a full description of this parameter if
> I fire up Google, and search online.  In fact, more likely than
> not, I'll find far more documentation than I want.  But my point
> is that a programmer should not need to do this.  The full
> documentation should be readily accessible directly through a few
> keystrokes.

You have first-grade documentation on the Python website: 
http://docs.python.org/library/urllib.html
I'm not really using pydoc, but I'd wager it's more used as a quick lookup 
than anything else.

> I would love to know how experienced Python programmers quickly
> zero in on the Python documentation they need.

I wouldn't count myself as an 'experienced' Python programmer, but I rely on 
docs.python.org for most things with regards to the standard library.

Cheers,

Emm


From __peter__ at web.de  Fri Jul 31 16:39:25 2009
From: __peter__ at web.de (Peter Otten)
Date: Fri, 31 Jul 2009 22:39:25 +0200
Subject: Python quirk in evaluation order
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <h4vkpr$3r5$01$1@news.t-online.com>

James Stroud wrote:

> py> b = 4 if True else b
> py> b
> 4

> Isn't the right side supposed to be evaluated first?

Perhaps it becomes clearer if you change it a bit:


>>> b = 4 if True else whatever
>>> whatever
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'whatever' is not defined

I. e. the else clause is never evaluated at all.

Peter



From breamoreboy at yahoo.co.uk  Fri Jul 31 16:55:35 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 31 Jul 2009 21:55:35 +0100
Subject: Python docs disappointing
In-Reply-To: <a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>
Message-ID: <h4vlnq$sh$1@ger.gmane.org>

r wrote:
> On Jul 31, 3:10 pm, kj <no.em... at please.post> wrote:
>> I'm pretty new to Python, and I like a lot overall, but I find the
>> documentation for Python rather poor, overall.
> [snip]
> 
> If you mean the built-in docs i *highly agree* with you. if you mean
> docs/tutorials available across the WWW i *highly disagree* with you,
> and if you mean the command line "help" i also *highly disagree*, of
> which python has the-best-in the-world!
> 
> I am using 2.6.2 and the help docs are a joke. trying to find even the
> simplest thing (built-in functions, etc...) is like pulling teeth. I
> do not look at them anymore, or do i plan to in the future. Luckily i
> know python pretty well, but i can't image the horrors a new Python
> Programmer must face now...
> 
> Kj, you could not be more right. Doc maintainers need to get some
> feedback from Python noobies when writing this stuff. Does anybody
> remember CP4E? I know Guido put a lot of effort into this project and
> very much believed in this philosophy(circa 1999~2005), although it
> never really went very far, i still believe in Guido's heart the CP4E
> exists -- if only barley clinging to life(...maybe?)
> 
> any thoughts on this Pythonistas?

I entirely agree with these comments.  Looking at home on the compiled 
help file on windows for python 2.6.2 I can't see anything except for 
some icons at the top, the Contents, Index, Search and Favorites tabs on 
the left and the following on the right.

What's new in Python 2.6? or all "What's new" documents since 2.0
Tutorial start here
Using Python how to use Python on different platforms
Language Reference describes syntax and language elements
Library Reference keep this under your pillow
Python HOWTOs in-depth documents on specific topics
Extending and Embedding tutorial for C/C++ programmers
Python/C API reference for C/C++ programmers
Installing Python Modules information for installers & sys-admins
Distributing Python Modules sharing modules with others
Documenting Python guide for documentation authors
Indices and tables:
Global Module Index quick access to all modules
General Index all functions, classes, terms
Glossary the most important terms explained
Search page search this documentation
Complete Table of Contents lists all sections and subsections
Meta information:
Reporting bugs
About the documentation  History and License of Python
Copyright

Apart from that what have the Pythonistas ever done for us? Nothing!:)

-- 
Kindest regards.

Mark Lawrence.



From nagle at animats.com  Fri Jul 31 16:56:25 2009
From: nagle at animats.com (John Nagle)
Date: Fri, 31 Jul 2009 13:56:25 -0700
Subject: beautiful soup
In-Reply-To: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
References: <87ae223b-7201-4fad-b10d-63bc839dbedd@v37g2000prg.googlegroups.com>
Message-ID: <4a7359ce$0$1629$742ec2ed@news.sonic.net>

xubin.cz wrote:
> hi, everyone
> 
> Is there any pakage or module handling html document like beautiful
> soup?

    Try "http://code.google.com/p/html5lib/".

That's supposed to be a parser which complies with the HTML 5 specification,
including its rules for handling bad HTML.

					John Nagle


From maxerickson at gmail.com  Fri Jul 31 17:04:10 2009
From: maxerickson at gmail.com (Max Erickson)
Date: Fri, 31 Jul 2009 21:04:10 +0000 (UTC)
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
	<4A734E29.9080708@mrabarnett.plus.com>
Message-ID: <Xns9C59AD9F315DDmaxericksongmailcom@80.91.229.13>

MRAB <python at mrabarnett.plus.com> wrote:

> Brandon Fredericks wrote:
>> I did a search within this group, but couldn't find any
>> information on this.
>> 
>> I am sending base64 encoded data as the content over http using
>> urllib2 urlopen. When I receive the data and attempt to decode
>> it, I get an "Incorrect Padding" error. Is there a simple way to
>> fix this? A better way to send and receive the data possibly
>> (using base64 of course)?
> 
> Base-64 encodes 3 bytes (echo in the range 0-255) to 4 bytes
> (each in a more restricted range). The length of the output is
> _always_ a multiple of 4 (ignoring whitespace); the method adds
> extra padding bytes (ASCII '=') to ensure that this is the case
> if the length of the input isn't a multiple of 3.
> 
> So, if decoding raises an "Incorrect Padding" error then strip
> out any whitespace and append extra ASCII '=' to make its length
> a multiple of 3, then try decoding again. (Or you could just
> repeatedly add one pad character and retry, up to 3 times.)

The length of the encoded string should be a multiple of 4 (as you 
state in the second sentence of your post), not a multiple of 3.


max



From davea at ieee.org  Fri Jul 31 17:07:01 2009
From: davea at ieee.org (Dave Angel)
Date: Fri, 31 Jul 2009 17:07:01 -0400
Subject: Python quirk in evaluation order
In-Reply-To: <h4vj65$40k$1@zinnia.noc.ucla.edu>
References: <h4vj65$40k$1@zinnia.noc.ucla.edu>
Message-ID: <4A735CF5.1070304@ieee.org>

James Stroud wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Python 2.5:
>
> mbi136-176 211% python
> *** Pasting of code with ">>>" or "..." has been enabled.
> ########################################################################
>  ##                             ipython                              ##
> ########################################################################
> py> b = 4 if True else b
> py> b
> 4
>
>
> Isn't the right side supposed to be evaluated first?
>

I don't have a clue what value you expected b to have.  The if/else 
ternary expression is roughly equivalent to:
              if True:
                    b = 4
              else
                    b = b
The first part to be evaluated is the if expression, which is hard-coded 
to True.  Then the part to the left will be used for the expression 
result, and the part on the right ignored.  This is because of 
short-circuit rules.

Try this one for size:
b = 22 if True else  I.am.Not.Being.Evaluated(4.4)

The else clause does need to be a syntactically valid expression, but 
it's not evaluated unless the if-expression is false.

DaveA




From pavlovevidence at gmail.com  Fri Jul 31 17:16:48 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 14:16:48 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>

On Jul 31, 1:10?pm, kj <no.em... at please.post> wrote:
> I'm pretty new to Python, and I like a lot overall, but I find the
> documentation for Python rather poor, overall.
>
> I'm sure that Python experts don't have this problem: they have
> internalized some good ways to access the documentation, are
> productive with it, and therefore have lost the ability to see why
> the Python documentations is deficient for beginners.

That may be so, but I do remember when I was a beginner myself and I
had no issue with the documentation.


[snip]
> I'm sure that I can find a full description of this parameter if
> I fire up Google, and search online.

Are you aware that Python ships with a full set of documentation,
where (for instance) the meaning of "data" in urllib is defined?  You
don't need Google.


> In fact, more likely than
> not, I'll find far more documentation than I want. ?But my point
> is that a programmer should not need to do this. ?The full
> documentation should be readily accessible directly through a few
> keystrokes.

Well, no one volunteered to do that.  Oh well.


> I would love to know how experienced Python programmers quickly
> zero in on the Python documentation they need.

Choose bookmark in web browser for Python documentation -> keyword
search for correct module (easy with firefox) -> scroll.

This might not be the smoothest method ever (omg you have to use a
*mouse*) but it should be usable enough.


Carl Banks


From python at mrabarnett.plus.com  Fri Jul 31 17:17:30 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 22:17:30 +0100
Subject: base64 Incorrect Padding
In-Reply-To: <Xns9C59AD9F315DDmaxericksongmailcom@80.91.229.13>
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>	<4A734E29.9080708@mrabarnett.plus.com>
	<Xns9C59AD9F315DDmaxericksongmailcom@80.91.229.13>
Message-ID: <4A735F6A.1010405@mrabarnett.plus.com>

Max Erickson wrote:
> MRAB <python at mrabarnett.plus.com> wrote:
> 
>> Brandon Fredericks wrote:
>>> I did a search within this group, but couldn't find any
>>> information on this.
>>>
>>> I am sending base64 encoded data as the content over http using
>>> urllib2 urlopen. When I receive the data and attempt to decode
>>> it, I get an "Incorrect Padding" error. Is there a simple way to
>>> fix this? A better way to send and receive the data possibly
>>> (using base64 of course)?
>> Base-64 encodes 3 bytes (echo in the range 0-255) to 4 bytes
>> (each in a more restricted range). The length of the output is
>> _always_ a multiple of 4 (ignoring whitespace); the method adds
>> extra padding bytes (ASCII '=') to ensure that this is the case
>> if the length of the input isn't a multiple of 3.
>>
>> So, if decoding raises an "Incorrect Padding" error then strip
>> out any whitespace and append extra ASCII '=' to make its length
>> a multiple of 3, then try decoding again. (Or you could just
>> repeatedly add one pad character and retry, up to 3 times.)
> 
> The length of the encoded string should be a multiple of 4 (as you 
> state in the second sentence of your post), not a multiple of 3.
> 
Oops, correct! :-)


From masklinn at masklinn.net  Fri Jul 31 17:19:07 2009
From: masklinn at masklinn.net (Masklinn)
Date: Fri, 31 Jul 2009 23:19:07 +0200
Subject: Python docs disappointing
In-Reply-To: <200907312234.06374.emmanuel.surleau@gmail.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<200907312234.06374.emmanuel.surleau@gmail.com>
Message-ID: <E8ADB0D7-6DD2-4378-A74E-05A9383137A0@masklinn.net>

On 31 Jul 2009, at 22:34 , Emmanuel Surleau wrote:
> You have first-grade documentation on the Python website:
> http://docs.python.org/library/urllib.html
> I'm not really using pydoc, but I'd wager it's more used as a quick  
> lookup
> than anything else.
Another important documentary resource for the stdlib is Doug  
Hellmann's awesome Python Module of the Day series (http://www.doughellmann.com/PyMOTW/ 
)


From pavlovevidence at gmail.com  Fri Jul 31 17:23:02 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 14:23:02 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<a23ecb48-545b-4751-8c61-6493c2488871@f37g2000yqn.googlegroups.com>
	<mailman.4073.1249073738.8015.python-list@python.org>
Message-ID: <7bb4df03-f09a-40b0-83f8-1c6d0c9800a8@j21g2000vbn.googlegroups.com>

On Jul 31, 1:55?pm, Mark Lawrence <breamore... at yahoo.co.uk> wrote:
> Apart from that what have the Pythonistas ever done for us? Nothing!:)


Please don't feed the trolls.

And if you do feed the trolls don't smile at them.


Carl Banks


From no.email at please.post  Fri Jul 31 17:28:36 2009
From: no.email at please.post (kj)
Date: Fri, 31 Jul 2009 21:28:36 +0000 (UTC)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
Message-ID: <h4vnm4$jvi$1@reader1.panix.com>

In <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4 at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevidence at gmail.com> writes:

>(omg you have to use a
>*mouse*)

That's precisely the point.  There's a huge number of programmers
out there who, like me, *hate* to use the mouse while they're
coding.  It is truly disappointing to us that the developers of
Python chose to completely disregard this constituency.

This is one area in which Perl still whips Python...

kynn 


From rt8396 at gmail.com  Fri Jul 31 17:30:47 2009
From: rt8396 at gmail.com (r)
Date: Fri, 31 Jul 2009 14:30:47 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
Message-ID: <4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>

On Jul 31, 4:16?pm, Carl Banks <pavlovevide... at gmail.com> wrote:
> On Jul 31, 1:10?pm, kj <no.em... at please.post> wrote:
>
> > I'm pretty new to Python, and I like a lot overall, but I find the
> > documentation for Python rather poor, overall.
>
> > I'm sure that Python experts don't have this problem: they have
> > internalized some good ways to access the documentation, are
> > productive with it, and therefore have lost the ability to see why
> > the Python documentations is deficient for beginners.
>
> That may be so, but I do remember when I was a beginner myself and I
> had no issue with the documentation.

have you tried the new docs (>= 2.6) The interface has changed
drastically as to render itself completely useless. The old docs (<=
2.5) --the ones i learned from-- where flawless.


@ Mark Lawrence
Have you clicked any of those links? try the "Tutorial start here" and
then try to find a menu of sorts. It seems you have to click "next" to
navigate. Thats pretty counter intuitive if you need to get to page
589!! Upon clicking the tutorial link in the OLD DOCS, you where
presented with a nice menu for concise navigation.


From python at rcn.com  Fri Jul 31 17:43:17 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 14:43:17 -0700 (PDT)
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<86b332b3-2da0-44e0-b29f-d930136635df@u16g2000pru.googlegroups.com> 
	<mailman.4061.1249066087.8015.python-list@python.org>
Message-ID: <4677d753-364f-4d29-9091-e55008daec83@12g2000pri.googlegroups.com>

> > While nothing in the list/tuple code requires you to make that
> > distinction,
> > it is important because that philosophy pervades the language. ?If you
> > follow Guido's direction, you'll find that the various parts of the
> > language fit together better. ?Do otherwise and you'll be going
> > against
> > the grain.
>
> I might be wrong, but I get the impression that many people don't indeed "get
> it" and use tuples as static arrays and lists when the array needs to be
> dynamically resized. This is certainly how I use them as well.
>
> This would tend to show that Guido's notion here was not particularly
> intuitive.

No, it just shows that they are not Dutch ;-)

IIRC, Aahz once made an eloquent statement about how languages aren't
intuitive because different people have different intuitions.  The
fact
is that every language has its own set of ways.  People usually pick-
up
on what is Pythonic in a short order.  The problem comes when people
decide-in-advance how the language ought to be -- it takes them longer
to pick-up the culture and idioms.  More than one person here has
observed that the time to learn to program Pythonically is inversely
proportional to their experience in Java.

It is perfectly okay for you to use tuples for statically sized
arrays.
That isn't wrong.  It is against then grain though.  Guido articulated
his concept early and many of his minions (me included) have designed
the APIs and optimizations to flow nicely with his preferred way of
doing things.


Raymond


From breamoreboy at yahoo.co.uk  Fri Jul 31 17:53:02 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Fri, 31 Jul 2009 22:53:02 +0100
Subject: Python docs disappointing
In-Reply-To: <4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>
Message-ID: <h4vp3d$9kr$1@ger.gmane.org>

r wrote:
> On Jul 31, 4:16 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
>> On Jul 31, 1:10 pm, kj <no.em... at please.post> wrote:
>>
>>> I'm pretty new to Python, and I like a lot overall, but I find the
>>> documentation for Python rather poor, overall.
>>> I'm sure that Python experts don't have this problem: they have
>>> internalized some good ways to access the documentation, are
>>> productive with it, and therefore have lost the ability to see why
>>> the Python documentations is deficient for beginners.
>> That may be so, but I do remember when I was a beginner myself and I
>> had no issue with the documentation.
> 
> have you tried the new docs (>= 2.6) The interface has changed
> drastically as to render itself completely useless. The old docs (<=
> 2.5) --the ones i learned from-- where flawless.
> 
> 
> @ Mark Lawrence
> Have you clicked any of those links? try the "Tutorial start here" and
> then try to find a menu of sorts. It seems you have to click "next" to
> navigate. Thats pretty counter intuitive if you need to get to page
> 589!! Upon clicking the tutorial link in the OLD DOCS, you where
> presented with a nice menu for concise navigation.

Yes.  Works perfectly as evidenced by the fact that this evening I've 
checked data on the cProfile, pstats and array modules.

-- 
Kindest regards.

Mark Lawrence.



From python at rcn.com  Fri Jul 31 17:55:16 2009
From: python at rcn.com (Raymond Hettinger)
Date: Fri, 31 Jul 2009 14:55:16 -0700 (PDT)
Subject: Help understanding the decisions *behind* python? - immutable 
	objects
References: <mailman.3431.1248107247.8015.python-list@python.org> 
	<54411136-ffe1-49c7-b102-f99c5890ce21@k6g2000yqn.googlegroups.com> 
	<mailman.3511.1248244497.8015.python-list@python.org>
	<9c6c98d6-fced-4ab6-ba65-245b1c7714eb@g31g2000yqc.googlegroups.com>
	<4a6c9ec0$0$1636$742ec2ed@news.sonic.net>
Message-ID: <6b343b95-27d0-4167-bef2-d3e0a5fd87dc@u38g2000pro.googlegroups.com>

On Jul 26, 11:24?am, John Nagle <na... at animats.com> wrote:
> A tuple is really a frozen list. ?Arguably, frozen objects
> should have been a general concept. ?Conceptually, they're
> simple - once "__init__" has run, there can be no more changes
> to fields of the object.

I would argue that freezing and thawing (making the container
statefull)
is the proverbial road to hell paved with good intentions.  It is
roughly in the same category as dynamic scoping -- programs become
harder to analyze for correctness -- code that used to work can
break because something froze it along the way (perhaps to use it
as a key for dict or set in a caching function) or because something
unfroze it (so it could mutate a value).


Raymond



From brfredericks at gmail.com  Fri Jul 31 17:58:43 2009
From: brfredericks at gmail.com (bfrederi)
Date: Fri, 31 Jul 2009 14:58:43 -0700 (PDT)
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
	<mailman.4067.1249070631.8015.python-list@python.org>
Message-ID: <b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>

So what if I used a different encoding that isn't ASCII? Like UTF-8?
Would that give me lengths that are multiples of 4 based on how the
characters are represented? Or would I still need to pad with '='?


From pavlovevidence at gmail.com  Fri Jul 31 18:03:25 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 15:03:25 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
Message-ID: <09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>

On Jul 31, 2:28?pm, kj <no.em... at please.post> wrote:
> In <e22013d0-fbad-44e0-919b-ad5bb5f2d... at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevide... at gmail.com> writes:
>
> >(omg you have to use a
> >*mouse*)
>
> That's precisely the point. ?There's a huge number of programmers
> out there who, like me, *hate* to use the mouse while they're
> coding.

You would have figured one of them would have written a script or
something if there were so many.  Maybe check the Python Cookbook for
someone's pet trick, I bet there is one or two there.  Or figure out a
way to use elinks, the text mode web browser.  You know, text mode
browsers have come a long way since the lynx days.


>?It is truly disappointing to us that the developers of
> Python chose to completely disregard this constituency.

Python is a volunteer effort, chief.

If all these programmers have this itch, as you claim, they've all
disregarded themselves by failing to contribute something.


> This is one area in which Perl still whips Python...

No way.  Perl's man pages are organized so poorly there is no
ergonomic pit deep enough to offset them.  Quick, what man page is the
"do" statement documented in?


Carl Banks


From no.email at please.post  Fri Jul 31 18:09:42 2009
From: no.email at please.post (kj)
Date: Fri, 31 Jul 2009 22:09:42 +0000 (UTC)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
Message-ID: <h4vq36$4ik$1@reader1.panix.com>

In <09bf4f17-40a5-4bad-81d3-1950545b7570 at g6g2000vbr.googlegroups.com>
Carl Banks <pavlovevidence at gmail.com> writes:

<snip>

Thanks.  Your remarks at least confirm that my impression was not
simply due to my noob ignorance: the keyboard-accessible docs are
indeed as poor as they look.

kynn


From pfeldman at verizon.net  Fri Jul 31 18:17:56 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 31 Jul 2009 15:17:56 -0700 (PDT)
Subject: possible to round number and convert to string?
Message-ID: <24763821.post@talk.nabble.com>


I'd like to be able to convert a float to a string representation in which
the number is rounded to a specified number of digits.  If num2str is a
hypothetical function that does this, then num2str(pi,3) would be '3.142'
(not '3.141').  I've been told that there is no such function in Python.  I
tried to write this myself, but wasn't successful.  Any suggestions will be
appreciated.
-- 
View this message in context: http://www.nabble.com/possible-to-round-number-and-convert-to-string--tp24763821p24763821.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From python at mrabarnett.plus.com  Fri Jul 31 18:24:09 2009
From: python at mrabarnett.plus.com (MRAB)
Date: Fri, 31 Jul 2009 23:24:09 +0100
Subject: base64 Incorrect Padding
In-Reply-To: <b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>	<mailman.4067.1249070631.8015.python-list@python.org>
	<b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>
Message-ID: <4A736F09.6090505@mrabarnett.plus.com>

bfrederi wrote:
> So what if I used a different encoding that isn't ASCII? Like UTF-8?
> Would that give me lengths that are multiples of 4 based on how the
> characters are represented? Or would I still need to pad with '='?

I think that when it says Base-64 it's talking about the byte values
used for the encoding.


From david.birdsong at gmail.com  Fri Jul 31 18:27:19 2009
From: david.birdsong at gmail.com (birdsong)
Date: Fri, 31 Jul 2009 15:27:19 -0700 (PDT)
Subject: Non-blocking read with popen subprocess
References: <77a55a40-79b5-45c1-a72e-af42528c6e3e@l5g2000pra.googlegroups.com>
	<824f8092-55b1-4df2-a6b5-74a4b1b1d9ea@i18g2000pro.googlegroups.com>
Message-ID: <fa7a8d57-57eb-4ec3-984d-b10cd5c10348@i18g2000pro.googlegroups.com>

On Jul 30, 7:30?pm, Jonathan Gardner <jgard... at jonathangardner.net>
wrote:
> On Jul 30, 5:24?pm, Dhanesh <dhanesh... at gmail.com> wrote:
>
>
>
> > how can I we have a non blocking read ?
>
> Seehttp://docs.python.org/library/popen2.html#flow-control-issues
>
> Note well: In the non-blocking world, you have to use select() or poll
> () to get your job done.

I solved a problem just yesterday regarding select on a Popen.stdout
file descriptor that was created with a 100Mb buffer.  I'd love it if
anybody could critique my solution and my understanding of my
findings.

In my case, select would return with my Popen object ready for read,
I'd go off and try to read and then my read would block.  After a few
strace's I found that Popen.stdout.read(), which I am assuming is the
same as the read builtin, would make multiple read system calls, in
many cases blocking until it returned my default buffer size.

Sure enough, it's in the docs: http://docs.python.org/library/stdtypes.html?highlight=fread
"""
Note that this method may call the underlying C function fread() more
than once in an effort to acquire as close to size bytes as possible.
Also note that when in non-blocking mode, less data than was requested
may be returned, even if no size parameter was given.
"""

I couldn't find a way to tell subprocess to return my stdout fd in non-
blocking mode, but then I thought about it not being a problem with
the fd and how it was opened as much as a problem with the read
call.

  A non-blocking fd will have a read call throw EWOULDBLOCK when asked
for more bytes than is in buffer, a blocking fd would have read just
return fewer bytes  ...do I have this this right?

I can handle assembling the data fine, I just don't want to block.

I wrote a little test program to spit out random stdout to test a
Popen object's stdout in os.read.  The len() of the result of os.read
was all over the place depending on how quickly i re-ran read() on the
fd.  There were slight delays from time to time, but I attributed that
to the interpreter being context switched in, ssh delays ...or the
weather...in general the return was pretty fast.

I switched my program to use os.read and now it's snappy and spends
most of it's time blocking on select exactly where I want it to.

(this is on linux btw, I guess os.read is different everywhere)

> You may want to look at "communicate" (http://docs.python.org/library/subprocess.html#popen-objects) which may be what you need.



From Nikolaus at rath.org  Fri Jul 31 18:38:25 2009
From: Nikolaus at rath.org (Nikolaus Rath)
Date: Fri, 31 Jul 2009 18:38:25 -0400
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
Message-ID: <87prbgscke.fsf@vostro.rath.org>

Carl Banks <pavlovevidence at gmail.com> writes:
>> This is one area in which Perl still whips Python...
>
> No way.  Perl's man pages are organized so poorly there is no
> ergonomic pit deep enough to offset them.  Quick, what man page is the
> "do" statement documented in?

Of course there is:

$ perldoc -f do | head
       do BLOCK
               Not really a function.  Returns the value of the last command
               in the sequence of commands indicated by BLOCK.  When modified
               by the "while" or "until" loop modifier, executes the BLOCK
               once before testing the loop condition. (On other statements
               the loop modifiers test the conditional first.)

               "do BLOCK" does not count as a loop, so the loop control
               statements "next", "last", or "redo" cannot be used to leave or
               restart the block.  See perlsyn for alternative strategies.
$ 


Best,

   -Nikolaus

-- 
 ?Time flies like an arrow, fruit flies like a Banana.?

  PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6  02CF A9AD B7F8 AE4E 425C


From malaclypse2 at gmail.com  Fri Jul 31 18:42:03 2009
From: malaclypse2 at gmail.com (Jerry Hill)
Date: Fri, 31 Jul 2009 18:42:03 -0400
Subject: possible to round number and convert to string?
In-Reply-To: <24763821.post@talk.nabble.com>
References: <24763821.post@talk.nabble.com>
Message-ID: <16651e80907311542w1a94168egd173641cdfb002ce@mail.gmail.com>

On Fri, Jul 31, 2009 at 6:17 PM, Dr. Phillip M.
Feldman<pfeldman at verizon.net> wrote:
>
> I'd like to be able to convert a float to a string representation in which
> the number is rounded to a specified number of digits. ?If num2str is a
> hypothetical function that does this, then num2str(pi,3) would be '3.142'
> (not '3.141'). ?I've been told that there is no such function in Python. ?I
> tried to write this myself, but wasn't successful. ?Any suggestions will be
> appreciated.

You should be able to do this with standard string formatting.  (
http://docs.python.org/library/stdtypes.html#string-formatting )

For example:
>>> from math import pi
>>> pi
3.1415926535897931
>>> "%0.3f" % pi
'3.142'

If you need it as a function, you could do something like this:
>>> def num2str(num, precision):
	return "%0.*f" % (precision, num)

>>> num2str(pi, 4)
'3.1416'

Does that do what you need?

-- 
Jerry


From user at example.net  Fri Jul 31 18:42:21 2009
From: user at example.net (superpollo)
Date: Sat, 01 Aug 2009 00:42:21 +0200
Subject: possible to round number and convert to string?
In-Reply-To: <mailman.4079.1249078685.8015.python-list@python.org>
References: <mailman.4079.1249078685.8015.python-list@python.org>
Message-ID: <4a737350$0$28514$4fafbaef@reader2.news.tin.it>

Dr. Phillip M. Feldman wrote:
> I'd like to be able to convert a float to a string representation in which
> the number is rounded to a specified number of digits.  If num2str is a
> hypothetical function that does this, then num2str(pi,3) would be '3.142'
> (not '3.141').  I've been told that there is no such function in Python.  I
> tried to write this myself, but wasn't successful.  Any suggestions will be
> appreciated.

 >>> import math
 >>> s = str(round(math.pi, 3))
 >>> s
'3.142'
 >>>


From gallium.arsenide at gmail.com  Fri Jul 31 18:46:22 2009
From: gallium.arsenide at gmail.com (John Yeung)
Date: Fri, 31 Jul 2009 15:46:22 -0700 (PDT)
Subject: possible to round number and convert to string?
References: <mailman.4079.1249078685.8015.python-list@python.org>
Message-ID: <3b719e5e-0cce-4059-86e1-623a0ad7777a@f33g2000vbm.googlegroups.com>

On Jul 31, 6:17?pm, "Dr. Phillip M. Feldman" <pfeld... at verizon.net>
wrote:
> I'd like to be able to convert a float to a
> string representation in which the number is
> rounded to a specified number of digits. ?If
> num2str is a hypothetical function that does
> this, then num2str(pi,3) would be '3.142'
> (not '3.141'). ?I've been told that there is
> no such function in Python. ?I tried to write
> this myself, but wasn't successful. ?Any
> suggestions will be appreciated.

This is what I get in Python 2.6.1 on Windows:

>>> from math import pi
>>> pi
3.1415926535897931
>>> round(pi, 3)
3.1419999999999999
>>> str(round(pi, 3))
'3.142'

John


From cjns1989 at gmail.com  Fri Jul 31 18:54:52 2009
From: cjns1989 at gmail.com (Chris Jones)
Date: Fri, 31 Jul 2009 18:54:52 -0400
Subject: Python docs disappointing
In-Reply-To: <09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
Message-ID: <20090731225452.GK25977@turki.gavron.org>

On Fri, Jul 31, 2009 at 06:03:25PM EDT, Carl Banks wrote:
> On Jul 31, 2:28?pm, kj <no.em... at please.post> wrote:
> > In <e22013d0-fbad-44e0-919b-ad5bb5f2d... at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevide... at gmail.com> writes:
> >
> > >(omg you have to use a
> > >*mouse*)
> >
> > That's precisely the point. ?There's a huge number of programmers
> > out there who, like me, *hate* to use the mouse while they're
> > coding.
> 
> You would have figured one of them would have written a script or
> something if there were so many.  Maybe check the Python Cookbook for
> someone's pet trick, I bet there is one or two there.  Or figure out a
> way to use elinks, the text mode web browser.  You know, text mode
> browsers have come a long way since the lynx days.

So true.. I would add that one of the unplanned merits of a well-thought
out text mode browser such as ELinks is to remove all the fluff and
leave you, the reader, face to face with the site's content - or lack
thereof.

CJ


From pavlovevidence at gmail.com  Fri Jul 31 18:55:19 2009
From: pavlovevidence at gmail.com (Carl Banks)
Date: Fri, 31 Jul 2009 15:55:19 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
	<h4vq36$4ik$1@reader1.panix.com>
Message-ID: <109f1ff7-8fa9-40d3-80b4-1e90b5fc669c@d34g2000vbm.googlegroups.com>

On Jul 31, 3:09?pm, kj <no.em... at please.post> wrote:
> In <09bf4f17-40a5-4bad-81d3-1950545b7... at g6g2000vbr.googlegroups.com>
>
> Carl Banks <pavlovevide... at gmail.com> writes:
>
> <snip>
>
> Thanks. ?Your remarks at least confirm that my impression was not
> simply due to my noob ignorance: the keyboard-accessible docs are
> indeed as poor as they look.


In the standard library, docstrings (which is what pydoc prints) are
intended to be a brief explanation/reminder of usage, not an
exhaustive description.  Where docstrings are present, they are more
or less adequate for their intended use (although the quality of
docstrings does vary highly throughout the library).

If you are trying to use pydoc in a way not intended, then yes you
would likely find that they are poor when used in that unintended way.

Docstrings take up memory in a running process, so they are not ever
likely to be converted to an exhaustive description.  Your best bet is
to figure out a way to automate lookup in the html documentation.


Carl Banks


From aahz at pythoncraft.com  Fri Jul 31 19:09:16 2009
From: aahz at pythoncraft.com (Aahz)
Date: 31 Jul 2009 16:09:16 -0700
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
Message-ID: <h4vtis$n3e$1@panix3.panix.com>

In article <062813eb-7eec-4504-b32c-abadf02c3e38 at 12g2000pri.googlegroups.com>,
dandi kain  <dandi.kain at gmail.com> wrote:
>
>What is the functionality of __ or _ , leading or trailing an object ,
>class ot function ? Is it just a naming convention to note special
>functions and objects , or it really mean someting to Python ?

One more thing: if you have global module names with a single leading
underscore (e.g. "_foo"), they will not be loaded when you use

from <module> import *

However, "import *" is strongly discouraged for the most part.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From jeremy.cowles at gmail.com  Fri Jul 31 19:57:23 2009
From: jeremy.cowles at gmail.com (Jeremy Cowles)
Date: Fri, 31 Jul 2009 16:57:23 -0700
Subject: Bug with Python, Cygwin and /dev/urandom?
Message-ID: <373cf0740907311657j3e65d94mbbb2eda9e0f94fb7@mail.gmail.com>

urllib2.py is crashes when calling randombytes(n). I run the following under
Cygwin (mimicking how randombytes works):

$ python
Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
[GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys,os
>>> os.path.exists("/dev/urandom")
True
>>> f = open("/dev/urandom")
>>> s = f.read(2)
>>> f.close()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IOError: [Errno 0] Error


Errno 0 is supposed to be impossible according to the following thread.
Apparently this same issue also causes Mercurial to crash:
http://www.nabble.com/hg-1.0-exits-with-abort:-Error-td19021833.html


Is this a bug?


--
Jeremy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/5b636dfe/attachment-0001.html>

From rt8396 at gmail.com  Fri Jul 31 20:00:28 2009
From: rt8396 at gmail.com (r)
Date: Fri, 31 Jul 2009 17:00:28 -0700 (PDT)
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com> 
	<mailman.4078.1249077182.8015.python-list@python.org>
Message-ID: <dcf9e911-9935-48c9-b8bb-48d80ffcacd4@d32g2000yqh.googlegroups.com>

On Jul 31, 4:53?pm, Mark Lawrence <breamore... at yahoo.co.uk> wrote:
> r wrote:
> > On Jul 31, 4:16 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
> >> On Jul 31, 1:10 pm, kj <no.em... at please.post> wrote:
>
> >>> I'm pretty new to Python, and I like a lot overall, but I find the
> >>> documentation for Python rather poor, overall.
> >>> I'm sure that Python experts don't have this problem: they have
> >>> internalized some good ways to access the documentation, are
> >>> productive with it, and therefore have lost the ability to see why
> >>> the Python documentations is deficient for beginners.
> >> That may be so, but I do remember when I was a beginner myself and I
> >> had no issue with the documentation.
>
> > have you tried the new docs (>= 2.6) The interface has changed
> > drastically as to render itself completely useless. The old docs (<=
> > 2.5) --the ones i learned from-- where flawless.
>
> > @ Mark Lawrence
> > Have you clicked any of those links? try the "Tutorial start here" and
> > then try to find a menu of sorts. It seems you have to click "next" to
> > navigate. Thats pretty counter intuitive if you need to get to page
> > 589!! Upon clicking the tutorial link in the OLD DOCS, you where
> > presented with a nice menu for concise navigation.
>
> Yes. ?Works perfectly as evidenced by the fact that this evening I've
> checked data on the cProfile, pstats and array modules.
>
> --
> Kindest regards.
>
> Mark Lawrence.

Hold the phone... You checked data on modules using the "Tutorial
Start Here" link? Would not the "Global Module Index" be more, shall
we say, "informative"?


From kee at kagi.com  Fri Jul 31 20:12:43 2009
From: kee at kagi.com (Kee Nethery)
Date: Fri, 31 Jul 2009 17:12:43 -0700
Subject: Python docs disappointing - group effort to hire writers?
In-Reply-To: <109f1ff7-8fa9-40d3-80b4-1e90b5fc669c@d34g2000vbm.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
	<09bf4f17-40a5-4bad-81d3-1950545b7570@g6g2000vbr.googlegroups.com>
	<h4vq36$4ik$1@reader1.panix.com>
	<109f1ff7-8fa9-40d3-80b4-1e90b5fc669c@d34g2000vbm.googlegroups.com>
Message-ID: <756580E3-CFFA-404C-B66A-9F4281760C8E@kagi.com>

I too find the Python docs not very useful and it really slows down my  
learning curve.

I wonder if it would make sense to find good tech writers, get a  
quotes, and get some professionally written documentation WITH LOTS OF  
EXAMPLES added to the standard Python documentation tree.

I'd chip in money for that task. I've certainly spent enough buying  
Python books to where it would be very reasonable to chip in the cost  
of one book towards this project. Get enough people ... could be a  
great thing.

Even though it is not the version I use, I would suggest that the  
really detailed docs with lots of examples be written against the  
latest python version.

Just a thought.

Kee Nethery


From martin.hellwig at dcuktec.org  Fri Jul 31 20:14:33 2009
From: martin.hellwig at dcuktec.org (Martin P. Hellwig)
Date: Sat, 01 Aug 2009 01:14:33 +0100
Subject: Python docs disappointing
In-Reply-To: <h4vj45$5hl$1@reader1.panix.com>
References: <h4vj45$5hl$1@reader1.panix.com>
Message-ID: <oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>

kj wrote:
<cut python has poor documentation explanation>

Well to a level I agree with you.

If you are totally new to programming
_and_
you won't/can't invest in educational material
_and_
have an adversity for looking up resources using a web browser
_and_ don't have the patience for trial and error
*then*
getting proficient with the language is almost impossible.

Sometimes some modules are completely incomprehensible for me and that 
is after I have looked at the docstrings, the python doc and examples 
found using Google. However usually after combining all three with a 
fair bit of experimenting I figure it out, to me that is fun I like that 
kind of puzzles but I am aware that this isn't the best possible situation.

Overall I would say a better situation would be if the standard python 
documentation would have an *extensive* 'pattern' section for each 
module much like, for example, Frederik Lundh did this with his tkinter 
documentation. Incorporating these patterns in the standard 
documentation would save you some jumping around sites and it is perhaps 
more 'trustworthy' coming from the source (pun intended).

I believe that the documentation is all ReST format, so there should be 
a way (if there isn't already) to display the extensive documentation 
from the interpreter directly for the module you are working with. As 
you probably noticed, I actually never bothered to look if this isn't 
already the case. Which is a good indication to how much it has actually 
bothered me.

Furthermore I like to add to my reply, which is already longer then I 
anticipated at first, the thing I don't agree with you is the following 
(and comparative in nature): Compared to all other 'popular' languages I 
find Python actually very, very good documented and if you can't learn 
Python using the available documentation and on-line resources I think 
it is unlikely you can learn any other language, whether this is a 
programming language or a natural language. Actually, I should have 
replaced 'any' with 'anything' followed by a full stop.

-- 
MPH
http://blog.dcuktec.com
'If consumed, best digested with added seasoning to own preference.'


From breamoreboy at yahoo.co.uk  Fri Jul 31 20:20:32 2009
From: breamoreboy at yahoo.co.uk (Mark Lawrence)
Date: Sat, 01 Aug 2009 01:20:32 +0100
Subject: Python docs disappointing
In-Reply-To: <dcf9e911-9935-48c9-b8bb-48d80ffcacd4@d32g2000yqh.googlegroups.com>
References: <h4vj45$5hl$1@reader1.panix.com>	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>	<4679ca44-492d-457c-a1cb-1dd7e6181d24@b15g2000yqd.googlegroups.com>
	<mailman.4078.1249077182.8015.python-list@python.org>
	<dcf9e911-9935-48c9-b8bb-48d80ffcacd4@d32g2000yqh.googlegroups.com>
Message-ID: <h501nq$s2k$1@ger.gmane.org>

r wrote:
> On Jul 31, 4:53 pm, Mark Lawrence <breamore... at yahoo.co.uk> wrote:
>> r wrote:
>>> On Jul 31, 4:16 pm, Carl Banks <pavlovevide... at gmail.com> wrote:
>>>> On Jul 31, 1:10 pm, kj <no.em... at please.post> wrote:
>>>>> I'm pretty new to Python, and I like a lot overall, but I find the
>>>>> documentation for Python rather poor, overall.
>>>>> I'm sure that Python experts don't have this problem: they have
>>>>> internalized some good ways to access the documentation, are
>>>>> productive with it, and therefore have lost the ability to see why
>>>>> the Python documentations is deficient for beginners.
>>>> That may be so, but I do remember when I was a beginner myself and I
>>>> had no issue with the documentation.
>>> have you tried the new docs (>= 2.6) The interface has changed
>>> drastically as to render itself completely useless. The old docs (<=
>>> 2.5) --the ones i learned from-- where flawless.
>>> @ Mark Lawrence
>>> Have you clicked any of those links? try the "Tutorial start here" and
>>> then try to find a menu of sorts. It seems you have to click "next" to
>>> navigate. Thats pretty counter intuitive if you need to get to page
>>> 589!! Upon clicking the tutorial link in the OLD DOCS, you where
>>> presented with a nice menu for concise navigation.
>> Yes.  Works perfectly as evidenced by the fact that this evening I've
>> checked data on the cProfile, pstats and array modules.
>>
>> --
>> Kindest regards.
>>
>> Mark Lawrence.
> 
> Hold the phone... You checked data on modules using the "Tutorial
> Start Here" link? Would not the "Global Module Index" be more, shall
> we say, "informative"?

You asked "Have you clicked any of those links?".  I answered yes since 
they all work.  I usually navigate to module data via the index tab as I 
find this the easiest way.  I'm sure other people prefer the global 
module index.  Six of one, half a dozen of the other?

-- 
Kindest regards.

Mark Lawrence.



From aahz at pythoncraft.com  Fri Jul 31 20:39:20 2009
From: aahz at pythoncraft.com (Aahz)
Date: 31 Jul 2009 17:39:20 -0700
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
Message-ID: <h502ro$3n2$1@panix3.panix.com>

In article <h4vnm4$jvi$1 at reader1.panix.com>, kj  <no.email at please.post> wrote:
>In <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4 at g19g2000vbi.googlegroups.com> Carl Banks <pavlovevidence at gmail.com> writes:
>>
>>(omg you have to use a *mouse*)
>
>That's precisely the point.  There's a huge number of programmers out
>there who, like me, *hate* to use the mouse while they're coding.  It
>is truly disappointing to us that the developers of Python chose to
>completely disregard this constituency.

That's why I use Lynx on a local copy of the Python docs.  Next question?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer


From pfeldman at verizon.net  Fri Jul 31 20:42:57 2009
From: pfeldman at verizon.net (Dr. Phillip M. Feldman)
Date: Fri, 31 Jul 2009 17:42:57 -0700 (PDT)
Subject: possible to round number and convert to string?
In-Reply-To: <4a737350$0$28514$4fafbaef@reader2.news.tin.it>
References: <24763821.post@talk.nabble.com>
	<4a737350$0$28514$4fafbaef@reader2.news.tin.it>
Message-ID: <24764948.post@talk.nabble.com>


This was very close to what I wanted.  Thanks!  My final code looks like
this:

def num2str(x,f=4):
   """Convert x (int or float) to a string with f digits to right of
   the decimal point.  f may be zero or negative, in which case the decimal
   point is suppressed."""
   s= str(round(x,f))
   if f<=0:
      # Delete decimal point:
      i= s.find('.')
      if i>0: s= s[:i]
   return s
-- 
View this message in context: http://www.nabble.com/possible-to-round-number-and-convert-to-string--tp24763821p24764948.html
Sent from the Python - python-list mailing list archive at Nabble.com.



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 20:46:22 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 21:46:22 -0300
Subject: threads check socket
References: <f91c5196-0212-4013-8647-af771c52da8a@x5g2000prf.googlegroups.com>
	<mailman.4055.1249061007.8015.python-list@python.org>
	<7b3247b0-4c85-4290-9de2-41fc45348d3d@z4g2000prh.googlegroups.com>
Message-ID: <op.uxykfkitx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 14:42:29 -0300, NighterNet <darkneter at gmail.com>  
escribi?:
> On Jul 31, 10:23?am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
> wrote:
>> En Fri, 31 Jul 2009 13:35:10 -0300, NighterNet <darkne... at gmail.com>  
>> escribi?:

>> > I been trying to find a way to check the socket is open or not. The
>> > thread are in a group and loop if the sockets are open. If they are
>> > not open delete the thread and remove the group. I need on this.
>>
>> What means an "open socket"? Do you want to detect whether the other  
>> side ?
>> closed the connection? In that case reading from the socket returns an ?
>> empty string.
>>
>> Regarding the "threads in a group", I don't understand what you mean.  
>> But ?
>> in general, you don't delete a thread, you just return from its run() ?
>> method and the thread finishes execution.
>
> Thread added into the array.

Which array?

> Well this thread when user leave the
> server want to make sure it not in used so that I can reuse it some
> how or move into another array.

Sorry but it's hard to help if you don't provide enough background. Looks  
like you're developing a game server; maybe this story is relevant to you:
http://comments.gmane.org/gmane.comp.python.general/627319

Assuming you're talking about TCP: when the client closes the connection  
gracefully, you get an empty string '' when reading from the socket. If  
the client loses the connection abruptly (the power goes down, the network  
is broken, the process is killed...) you get no indication of that. You  
may need to implement some mechanism (a PING? query/response, or perhaps  
the client must send an "I'm alive!" message once each N minutes; no  
answer means it's down and the server closes the connection).

> Need to know the thread speed that need for game server timer to
> control it. Don't want it too fast or slow for the game server.
> fps = 30
> 	def run(self):
> 		while True:
> 			self.gametime += 1
> 			if self.gametime > 10000000/fps:
> 				self.gametime = 0;

What's this code used for, apart from sucking lots of CPU power?

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 21:02:56 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 22:02:56 -0300
Subject: base64 Incorrect Padding
References: <0fda9d64-ddfd-40c4-83a1-e3a1ea68ad03@s31g2000yqs.googlegroups.com>
	<mailman.4067.1249070631.8015.python-list@python.org>
	<b4654236-d360-4c66-918d-a875fa717952@32g2000yqj.googlegroups.com>
Message-ID: <op.uxyk66p8x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 18:58:43 -0300, bfrederi <brfredericks at gmail.com>  
escribi?:

> So what if I used a different encoding that isn't ASCII? Like UTF-8?
> Would that give me lengths that are multiples of 4 based on how the
> characters are represented? Or would I still need to pad with '='?

It doesn't matter, a base64-encoded string contains only ASCII characters.
How are you encoding the text? base64.b64encode does the padding for you,  
so you don't have to worry about that. Do as P. Otten suggests, try to  
send some known text and see what you actually get on the server. Most  
likely you'll find another problem (like trying to decode the complete  
HTTP response instead of just the entity body, or some other stupid  
mistake :) ).

-- 
Gabriel Genellina



From nagle at animats.com  Fri Jul 31 21:32:49 2009
From: nagle at animats.com (John Nagle)
Date: Fri, 31 Jul 2009 18:32:49 -0700
Subject: Module updating plans for Python 3.1: feedparser, MySQLdb
Message-ID: <4a739a96$0$1615$742ec2ed@news.sonic.net>

    Any progress on updating feedparser and MySQLdb for Python 3.x in the
foreseeable future?

    Feedparser shouldn't be that hard; it's just that nobody is working on it.
MySQLdb is known to be hard, and that may be a while.

				John Nagle


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 21:46:12 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 01 Aug 2009 01:46:12 GMT
Subject: Confessions of a Python fanboy
References: <e3725c9b-9f03-494a-a6a3-9d089f4f129c@d32g2000yqh.googlegroups.com>
	<008e82e8$0$9756$c3e8da3@news.astraweb.com>
	<aee48b3c0907310954t104a9630vbf60a0f0fddacfeb@mail.gmail.com>
	<mailman.4060.1249065676.8015.python-list@python.org>
Message-ID: <008f7990$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 20:41:12 +0200, Emmanuel Surleau wrote:

>> We don't actually *declare* that something is constant and then have
>> that declaration ignored. Python doesn't lie to us, although (as in any
>> language) a programmer might.
> 
> You could say that Ruby doesn't either, 

Well you could say a lot of things. Admittedly you don't need a separate 
"constant" declaration, but creating a variable name with an initial 
uppercase letter is sufficient to make it a (supposed) constant:

irb(main):049:0* Thing = 5
=> 5
irb(main):050:0> Thing = 7
(irb):50: warning: already initialized constant Thing
=> 7

As you can see, Ruby (well, irb at least) considers that Thing is a 
constant, and then goes ahead and changes it anyway.

Apart from the use of an arbitrary naming convention instead of an 
explicit "make this constant" declaration, and the feeble way Ruby 
capitulates when you change it, I think having actual write-once 
constants is actually a plus.


> you just need to read the
> documentation. Ruby's unwritten motto is "flexibility ?ber alles". In
> this regard, it is consistent (1). 

"It's consistent in its inconsistency" sort of thing perhaps?


> Not much is really bolted down in
> Ruby. You get encapsulation, but it's so easy to break that it's mostly
> symbolic. 

Out of curiosity, can you read/write class and instance attributes from 
outside the class without using a getter/setter?



-- 
Steven


From steve at REMOVE-THIS-cybersource.com.au  Fri Jul 31 21:48:09 2009
From: steve at REMOVE-THIS-cybersource.com.au (Steven D'Aprano)
Date: 01 Aug 2009 01:48:09 GMT
Subject: Python docs disappointing
References: <h4vj45$5hl$1@reader1.panix.com>
	<e22013d0-fbad-44e0-919b-ad5bb5f2ddb4@g19g2000vbi.googlegroups.com>
	<h4vnm4$jvi$1@reader1.panix.com>
Message-ID: <008f7a05$0$9756$c3e8da3@news.astraweb.com>

On Fri, 31 Jul 2009 21:28:36 +0000, kj wrote:

> In <e22013d0-fbad-44e0-919b-ad5bb5f2ddb4 at g19g2000vbi.googlegroups.com>
> Carl Banks <pavlovevidence at gmail.com> writes:
> 
>>(omg you have to use a
>>*mouse*)
> 
> That's precisely the point.  There's a huge number of programmers out
> there who, like me, *hate* to use the mouse while they're coding.


Complain to the developers of your web browser then. Or use a different 
web browser.


> It is
> truly disappointing to us that the developers of Python chose to
> completely disregard this constituency.

Python is open source software developed by a community of volunteers, so 
*you* are one of the developers of Python. You have an itch that needs 
scratching. Solve it yourself, and release it to the wider community, 
don't expect somebody else to do so.

Nobody is entitled to any functionality in Python. You can ask for it 
nicely, and if somebody thinks it's a good idea, and have nothing better 
to do, they may code it out of the goodness of their heart. Or you can do 
it yourself, or you can pay somebody to do it if you don't have the 
technical skill yourself. Or you can do without.


> This is one area in which Perl still whips Python...

If so, it's because Perl has more people who understand that the way to 
get something done is to do it, rather than whining about it.



-- 
Steven


From dciphercomputing at gmail.com  Fri Jul 31 21:53:47 2009
From: dciphercomputing at gmail.com (Simon)
Date: Fri, 31 Jul 2009 18:53:47 -0700 (PDT)
Subject: Newbie Question regarding __init__()
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
	<mailman.4058.1249065239.8015.python-list@python.org>
Message-ID: <ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>

Hi

So should the dcObject class include the "self" as well since I have
not defined an __init__ method in dcCursor?

Simon



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 22:06:39 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 23:06:39 -0300
Subject: Bug with Python, Cygwin and /dev/urandom?
References: <373cf0740907311657j3e65d94mbbb2eda9e0f94fb7@mail.gmail.com>
Message-ID: <op.uxyn5dr8x6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 20:57:23 -0300, Jeremy Cowles  
<jeremy.cowles at gmail.com> escribi?:

> urllib2.py is crashes when calling randombytes(n). I run the following  
> under
> Cygwin (mimicking how randombytes works):
>
> $ python
> Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
> [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import sys,os
>>>> os.path.exists("/dev/urandom")
> True
>>>> f = open("/dev/urandom")
>>>> s = f.read(2)
>>>> f.close()
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> IOError: [Errno 0] Error
>
>
> Errno 0 is supposed to be impossible according to the following thread.
> Apparently this same issue also causes Mercurial to crash:
> http://www.nabble.com/hg-1.0-exits-with-abort:-Error-td19021833.html
>
>
> Is this a bug?

It seems so, but not necesarily a Python one; it might be a bug in cygwin  
instead.
If not already reported, file a bug at http://bugs.python.org/

-- 
Gabriel Genellina



From python.list at tim.thechases.com  Fri Jul 31 22:39:31 2009
From: python.list at tim.thechases.com (Tim Chase)
Date: Fri, 31 Jul 2009 21:39:31 -0500
Subject: Python docs disappointing
In-Reply-To: <oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>
References: <h4vj45$5hl$1@reader1.panix.com>
	<oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>
Message-ID: <4A73AAE3.1050209@tim.thechases.com>

Martin P. Hellwig wrote:
> kj wrote:
[excerpt of previously snipped content restored]
>> I'm sure that I can find a full description of this parameter if
>> I fire up Google, and search online.  In fact, more likely than
>> not, I'll find far more documentation than I want.  But my point
>> is that a programmer should not need to do this.  The full
>> documentation should be readily accessible directly through a few
>> keystrokes.
> 
> Well to a level I agree with you.
[snip]
> have an adversity for looking up resources using a web browser

It may not be an adversity for looking things up using a 
web-browser, but rather the need to access documentation offline. 
  Whether on an airplane or simply away from a wifi/landline 
connection, there are plenty of times I'm coding offline (another 
reason I'm happy to have DVCS tools).

This thread prompted me to go digging a little further, and all 
the online docs are available in downloadable format, but you 
have to start by going to the base docs and chasing down the 
"downloads" rabbit-hole.  Perhaps it would be easier if there 
were some sort of back-link from individual pages, referencing 
the downloadable format package.

Combined with the downloaded HTML version of the docs (there are 
PDFs too if you prefer), using a lightweight browser like 
lynx/links/dillo, and optionally adding htdig for local 
search/indexing, you can access (and search) the full docs offline.

-tkc







From sjmachin at lexicon.net  Fri Jul 31 22:41:30 2009
From: sjmachin at lexicon.net (John Machin)
Date: Fri, 31 Jul 2009 19:41:30 -0700 (PDT)
Subject: .dbf tables and Null
References: <mailman.4059.1249065525.8015.python-list@python.org>
Message-ID: <2f4d5719-6ca8-4ef2-8734-420b3044b1dc@l35g2000pra.googlegroups.com>

On Aug 1, 3:41?am, Ethan Furman <et... at stoneleaf.us> wrote:
> Mornin'! ?and a good one, too, I hope.
>
> Question for you...
>
> First part of the question: ?What is the general value in having Null
> capability for fields?

In general, in any database system, so that one can distinguish
between "the customer has no 'middle name'" ('') and "the customer's
'middle name' is unknown" (NULL).

>
> Second part: ?Is there a tangible difference between Null, and the
> nothing of 0, '', False, etc, in python?

0 is the zero thing, it is not nothing. False is not nothing.


>
> Third part: ?If there is a tangible difference, do those of us who use
> python and these old, refuse-to-die, .dbf files actually have need of,
> or have tables including, Null values?
>
> P.S. part (for John Machin, if he sees this ?;)
> Will the dbf package you are working on support Null values?

My philosophy when digging stuff out of arcane storages is to expose
what is found and leave any kludging/sanitising to the next layer.

For example, None is returned for an N (Number) field that's all
spaces; it's up to the caller to decide whether to treat None as zero,
raise an exception, pop up a data-collection dialogue box, ...

If you mean specifically the Visual Foxpro v3 _NullFlags hack, yes, it
already supports that, as well as the VFP9 abuse of that hack for
Varchar and Varbinary fields :-)


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 22:58:40 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Fri, 31 Jul 2009 23:58:40 -0300
Subject: heapq "key" arguments
References: <97932d10-8601-401f-bb69-a98db9036929@p15g2000vbl.googlegroups.com>
	<1582f82e-34aa-4b66-b989-c9f8351a5f1c@o9g2000prg.googlegroups.com>
	<4f096546-36a1-4633-9a24-1265ce0929ce@q14g2000vbi.googlegroups.com>
Message-ID: <op.uxyqj2wwx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 16:38:01 -0300, Joshua Bronson <jabronson at gmail.com>  
escribi?:
> On Jul 31, 2:02?pm, Jonathan Gardner <jgard... at jonathangardner.net>  
> wrote:
>> On Jul 31, 10:44?am, Joshua Bronson <jabron... at gmail.com> wrote:

>> > Say I want to maintain a heap of (x, y) pairs sorted only by
>> > first coordinate. Without being able to pass key=itemgetter(0), won't
>> > heapifying a list of such pairs unnecessarily compare both
>> > coordinates?
>>
>> It will compare the second value only if the first values are equal.
>
> I don't see how that helps. That's not at all the same thing as being
> able to pass key=itemgetter(0).

Ok, it's not strictly the same, but usually it doesn't hurt. The heaqp  
module doesn't promise anything about equal elements: it may keep the  
original order, rearrange them at will, reverse them, whatever. So the  
element-wise comparison of tuples is as good as comparing only the first  
element - *except* when comparing the second element isn't cheap or has  
side effects or something like that. In that case, use a custom class to  
redefine comparison operators:

 from heapq import heapify, heappop

class tuplebyfirst(tuple):
     "tuple that sorts only on first element"
     def __lt__(self, other):
         return self[0]<other[0]

heap = [tuplebyfirst(x) for x in [(2, 3, 'A'), (1, 4, 'B'),
         (2, 5, 'C'), (2, 5, 'D'), (3, 0, 'E')]]
print heap
heapify(heap)
while heap:
     print heappop(heap)

Output:

[(2, 3, 'A'), (1, 4, 'B'), (2, 5, 'C'), (2, 5, 'D'), (3, 0, 'E')]
(1, 4, 'B')
(2, 5, 'C')
(2, 5, 'D')
(2, 3, 'A')
(3, 0, 'E')

The letters are just to recognize the original ordering.
(I've used an undocumented property: all heapq functions compare elements  
ONLY by using "<", in 2.6.2 at least. Defining all the other rich  
comparison methods doesn't change anything)

-- 
Gabriel Genellina



From ben+python at benfinney.id.au  Fri Jul 31 23:02:03 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 01 Aug 2009 13:02:03 +1000
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
	<3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>
	<337482f9-8ad9-4600-9cf4-39911f5368ac@h31g2000yqd.googlegroups.com>
Message-ID: <87ab2ktexg.fsf@benfinney.id.au>

BDZ <bdezonia at wisc.edu> writes:

> Unfortunately, although it has the calls I'd want, pysamba appears to
> be *nix only.

That's because Samba is *nix-only. If you want to use something knowing
that it's Samba, you are by definition working on *nix.

> I need something that will work under Windows.

In that case, forget the term ?samba?. What you want is the ability to
connect, *over a network*, to shares served via the SMB protocol suite.

Those shares might be implemented via Samba, MS Windows, or aything else
that can speak the SMB protocol suite. Your program, running on Windows,
should not need to care about Samba, only about the various SMB
protocols.

A search for ?site:pypi.python.org smb client? gets me directly to
<URL:http://pypi.python.org/pypi/PySmbClient/>. That's totally useless
to you though, unfortunately, since it depends on Samba installed ?
which you can't, by definition, on MS Windows.

> Is there a set of Python Windows functions (official or contributed)
> that might do what I need? (I'm new to Python)

Not that I know of. It would probably involve a Python wrapper around
the native MS Windows networking API, something which I'm not sure has
been done.

-- 
 \       ?Whenever you read a good book, it's like the author is right |
  `\   there, in the room talking to you, which is why I don't like to |
_o__)                                   read good books.? ?Jack Handey |
Ben Finney


From nat.williams at gmail.com  Fri Jul 31 23:13:05 2009
From: nat.williams at gmail.com (Nat Williams)
Date: Fri, 31 Jul 2009 22:13:05 -0500
Subject: Newbie Question regarding __init__()
In-Reply-To: <ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
	<mailman.4058.1249065239.8015.python-list@python.org>
	<ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>
Message-ID: <eb280f6e0907312013w165f5240w9bd5c7fbad8645e3@mail.gmail.com>

As MRAB described, ALL instance methods need to accept 'self' as a first
parameter, as that will be passed to them implicitly when they are called.
This includes __init__.  The name 'self' is just a commonly accepted
convention for the name of the instance object passed to methods.  You don't
have to call it that, but you really should.

Take a look at http://docs.python.org/tutorial/classes.html#class-objects
It might help shed some light on how methods and instances work.

One other thing.  I'm a little confused by the first line of
dcObject.__init__:

self.init_Pre() and self.init_Exec()

I suspect this does not do what you think it does.  init_Pre and init_Exec
will both be called by this expression (unless init_Pre throws an exception,
of course).  You're not getting anything here that you wouldn't by just
calling each method on a separate line, except just making it harder to
read.

Nat


On Fri, Jul 31, 2009 at 8:53 PM, Simon <dciphercomputing at gmail.com> wrote:

> Hi
>
> So should the dcObject class include the "self" as well since I have
> not defined an __init__ method in dcCursor?
>
> Simon
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20090731/3f9a41d4/attachment-0001.html>

From darkneter at gmail.com  Fri Jul 31 23:14:13 2009
From: darkneter at gmail.com (NighterNet)
Date: Fri, 31 Jul 2009 20:14:13 -0700 (PDT)
Subject: socket policy flash help
Message-ID: <04e26f53-5f51-476d-823e-47bfeed9b2a8@m7g2000prd.googlegroups.com>

I need help on the policy to able to let access to user to the server
once the policy access is finish. I been trying to find a good
example, but I got no luck. Using python version 3.1.

Here the code I tested but it not working.

if str(buff) == str("b\'<policy-file-request/>\\x00\'"):
				print ('policy FOUND >>> sending...')
				rawinput = str('<?xml version=\"1.0\"?><cross-domain-policy><allow-
access-from domain=\"*\" to-ports=\"*\" /></cross-domain-policy>')
				print (rawinput)
				b = bytes ( ord(c) for c in rawinput)
				self.sockfd.send(b);


From tjreedy at udel.edu  Fri Jul 31 23:18:35 2009
From: tjreedy at udel.edu (Terry Reedy)
Date: Fri, 31 Jul 2009 23:18:35 -0400
Subject: Python docs disappointing
In-Reply-To: <4A73AAE3.1050209@tim.thechases.com>
References: <h4vj45$5hl$1@reader1.panix.com>	<oLOdnbhmEZB3Fe7XnZ2dnUVZ8rydnZ2d@bt.com>
	<4A73AAE3.1050209@tim.thechases.com>
Message-ID: <h50c6a$dgf$1@ger.gmane.org>

Tim Chase wrote:

> It may not be an adversity for looking things up using a web-browser, 
> but rather the need to access documentation offline.  Whether on an 
> airplane or simply away from a wifi/landline connection, there are 
> plenty of times I'm coding offline (another reason I'm happy to have 
> DVCS tools).

This is one area where Windows users seems to have an advantage. The 
standard installer includes the doc set as a Windows help file. I often 
keep that open in one window while programming in others. I only later 
discovered that this was a copy of the online docs ;-), which I only use 
to check the in-development version before submitting a doc bug.



From ben+python at benfinney.id.au  Fri Jul 31 23:21:05 2009
From: ben+python at benfinney.id.au (Ben Finney)
Date: Sat, 01 Aug 2009 13:21:05 +1000
Subject: Does underscore has any special built-in meaningin Python ?
References: <062813eb-7eec-4504-b32c-abadf02c3e38@12g2000pri.googlegroups.com>
	<h4vtis$n3e$1@panix3.panix.com>
Message-ID: <873a8cte1q.fsf@benfinney.id.au>

aahz at pythoncraft.com (Aahz) writes:

> One more thing: if you have global module names with a single leading
> underscore (e.g. "_foo"), they will not be loaded when you use
> 
> from <module> import *
> 
> However, "import *" is strongly discouraged for the most part.

Dude, that's exactly the ?underscore has an effect on import but as a
beginner don't worry about it? that I avoided drawing attention to. The
explanation was just fine without that. But no, you have to find a way
to *contribute*, don't you?

Things were different before all these new-fangled changes, I say. Get
off my lawn.

-- 
 \       ?I love and treasure individuals as I meet them, I loathe and |
  `\     despise the groups they identify with and belong to.? ?George |
_o__)                                                     Carlin, 2007 |
Ben Finney


From gagsl-py2 at yahoo.com.ar  Fri Jul 31 23:22:35 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 01 Aug 2009 00:22:35 -0300
Subject: Help understanding the decisions *behind* python?
References: <mailman.3431.1248107247.8015.python-list@python.org>
	<200907312048.03922.emmanuel.surleau@gmail.com>
	<h4vi6u$ms8$1@ger.gmane.org>
	<200907312226.59027.emmanuel.surleau@gmail.com>
Message-ID: <op.uxyrnxfcx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 17:26:58 -0300, Emmanuel Surleau  
<emmanuel.surleau at gmail.com> escribi?:
> On Friday 31 July 2009 21:55:11 Terry Reedy wrote:

>> The word tuple comes from relational databases as a generalization of
>> single, double, triple, quadruple, quintuple, sextuple, sestuple,
>> octuple, etc. A tuple is a data record with a fixed number of fields
>> with individual meaning. There is nothing about homogeneity of data type
>> in that definition. A triple of floats is legitimately a tuple when each
>> is a coordinate (the individual meanings). In other contexts, the same
>> triple might properly be a list (such as of heights of people
>> arbitrarily ordered).
>
> My understanding is that, in this context, it's not so much data types  
> which
> are heterogeneous, but the semantic meaning of the data. For instance, a  
> tuple
> containing (first_name, last_name, address) would be a "legitimate"  
> tuple, but
> not a tuple containing (address, address, address), which, if we follow
> Guido's philosophy, ought to be represented as a list.

Note that years ago the distinction was much stronger: tuples had NO  
methods at all. All you could do with a tuple was: len(t), t[i], t1+t2,  
t*n, e in t, for e in t
Being so "crippled", thinking of tuples just as immutable lists probably  
wasn't so natural.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 23:31:25 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 01 Aug 2009 00:31:25 -0300
Subject: Newbie Question regarding __init__()
References: <e151398a-bf52-48d5-86c5-9742e06bc1a9@z28g2000vbl.googlegroups.com>
	<mailman.4058.1249065239.8015.python-list@python.org>
	<ba81b000-e8fc-4433-a371-c3c58b5aadd0@h21g2000yqa.googlegroups.com>
Message-ID: <op.uxyr2nemx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 22:53:47 -0300, Simon <dciphercomputing at gmail.com>  
escribi?:

> So should the dcObject class include the "self" as well since I have
> not defined an __init__ method in dcCursor?

Every method that you define takes "self" as its first argument.
Every method that you want to call on the current instance must be  
qualified by self.methodname(argu, ments) -- it is not different from  
anotherobject.methodname(...)
Every attribute that you want to access from the current instance must be  
qualified too: self.attributename
There is no implicit self/this in Python as in other languages.

-- 
Gabriel Genellina



From gagsl-py2 at yahoo.com.ar  Fri Jul 31 23:56:43 2009
From: gagsl-py2 at yahoo.com.ar (Gabriel Genellina)
Date: Sat, 01 Aug 2009 00:56:43 -0300
Subject: os.path.exists() and Samba shares
References: <42f0c423-657f-45fb-bec5-67dcdda9f4ad@a13g2000yqc.googlegroups.com>
	<3fdc924a-75ad-477a-be2e-6e42ce7bff0c@s15g2000yqs.googlegroups.com>
	<337482f9-8ad9-4600-9cf4-39911f5368ac@h31g2000yqd.googlegroups.com>
Message-ID: <op.uxys2nykx6zn5v@lepton.softlabbsas.com.ar>

En Fri, 31 Jul 2009 13:33:45 -0300, BDZ <bdezonia at wisc.edu> escribi?:
> On Jul 30, 4:41?pm, Lo?c Domaign? <loic.domai... at googlemail.com>
> wrote:

>> > Hello. I have written a Python 3.1 script running on Windows that uses
>> > os.path.exists() to connect to network shares. If the various network
>> > shares require different user account and password combos than the
>> > account the script is running under the routine returns false. I need
>> > something like os.samba.path.exists(username,password,path). Does
>> > anyone have a suggestion on how I can accomplish what I need to do in
>> > Python?
>>
>> Could the Python Samba module PySamba be interesting for  
>> you?http://sourceforge.net/projects/pysamba/
>
> Unfortunately, although it has the calls I'd want, pysamba appears to
> be *nix only. I need something that will work under Windows. Is there
> a set of Python Windows functions (official or contributed) that might
> do what I need? (I'm new to Python)

SAMBA is a Linux implementation of the SMB protocol, natively supported on
Windows. You may use the pywin32 package (available on sourceforge.net) to
call the WNetAddConnection2 Windows function:
http://msdn.microsoft.com/en-us/library/aa385413(VS.85).aspx

-- 
Gabriel Genellina